From 177525d26e31806d71653f74bbec13574b97892c Mon Sep 17 00:00:00 2001 From: Andreas Mohr Date: Sun, 3 Apr 2011 20:58:28 +0200 Subject: eradicate bashisms in scripts/patch-kernel Silence a remaining annoying (or worse, irritating - "is my entire patched tree broken now!?") bashism-related message that occurs when /bin/sh is configured to instead deploy dash, a POSIX-compliant shell, as is the pretty much standard case on e.g. Debian. Current kernel version is 2.6.38 ( Flesh-Eating Bats with Fangs) ===> linux-2.6.38.patch-kernel_test/scripts/patch-kernel: line 253: [: =: unary operator expected <=== cannot find patch file: patch-2.6.39 Signed-off-by: Andreas Mohr Signed-off-by: Michal Marek --- scripts/patch-kernel | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'scripts') diff --git a/scripts/patch-kernel b/scripts/patch-kernel index 46a59cae3a0a..20fb25c23382 100755 --- a/scripts/patch-kernel +++ b/scripts/patch-kernel @@ -250,7 +250,7 @@ while : # incrementing SUBLEVEL (s in v.p.s) do CURRENTFULLVERSION="$VERSION.$PATCHLEVEL.$SUBLEVEL" EXTRAVER= - if [ $STOPFULLVERSION = $CURRENTFULLVERSION ]; then + if [ x$STOPFULLVERSION = x$CURRENTFULLVERSION ]; then echo "Stopping at $CURRENTFULLVERSION base as requested." break fi -- cgit v1.2.3-71-gd317 From 466de9183570fe9fd21ef167951488fc9d513fcb Mon Sep 17 00:00:00 2001 From: Ben Hutchings Date: Sat, 19 Mar 2011 04:26:10 +0000 Subject: kconfig: Avoid buffer underrun in choice input commit 40aee729b350672c2550640622416a855e27938f ('kconfig: fix default value for choice input') fixed some cases where kconfig would select the wrong option from a choice with a single valid option and thus enter an infinite loop. However, this broke the test for user input of the form 'N?', because when kconfig selects the single valid option the input is zero-length and the test will read the byte before the input buffer. If this happens to contain '?' (as it will in a mips build on Debian unstable today) then kconfig again enters an infinite loop. Signed-off-by: Ben Hutchings Cc: stable@kernel.org [2.6.17+] Signed-off-by: Michal Marek --- scripts/kconfig/conf.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'scripts') diff --git a/scripts/kconfig/conf.c b/scripts/kconfig/conf.c index 659326c3e895..006ad817cd5f 100644 --- a/scripts/kconfig/conf.c +++ b/scripts/kconfig/conf.c @@ -332,7 +332,7 @@ static int conf_choice(struct menu *menu) } if (!child) continue; - if (line[strlen(line) - 1] == '?') { + if (line[0] && line[strlen(line) - 1] == '?') { print_help(child); continue; } -- cgit v1.2.3-71-gd317 From f094f8a1b2737a4f3ca46742ff9aaf460d39285e Mon Sep 17 00:00:00 2001 From: "Yann E. MORIN" Date: Thu, 24 Feb 2011 19:36:42 +0100 Subject: kconfig: allow multiple inclusion of the same file Allow 'source'ing the same file from multiple places (eg. from different files, and/or under different conditions). To avoid circular inclusion, scan the source-ancestry of the current file, and abort if already sourced in this branch. Regenerate the pre-parsed lex.zconf.c_shipped file. Signed-off-by: "Yann E. MORIN" Signed-off-by: Michal Marek --- scripts/kconfig/lex.zconf.c_shipped | 29 +++++++++++++++++++---------- scripts/kconfig/zconf.l | 29 +++++++++++++++++++---------- 2 files changed, 38 insertions(+), 20 deletions(-) (limited to 'scripts') diff --git a/scripts/kconfig/lex.zconf.c_shipped b/scripts/kconfig/lex.zconf.c_shipped index 6eb039718259..f4b3b1a15e21 100644 --- a/scripts/kconfig/lex.zconf.c_shipped +++ b/scripts/kconfig/lex.zconf.c_shipped @@ -2368,6 +2368,7 @@ void zconf_initscan(const char *name) void zconf_nextfile(const char *name) { + struct file *iter; struct file *file = file_lookup(name); struct buffer *buf = malloc(sizeof(*buf)); memset(buf, 0, sizeof(*buf)); @@ -2383,16 +2384,24 @@ void zconf_nextfile(const char *name) buf->parent = current_buf; current_buf = buf; - if (file->flags & FILE_BUSY) { - printf("%s:%d: do not source '%s' from itself\n", - zconf_curname(), zconf_lineno(), name); - exit(1); - } - if (file->flags & FILE_SCANNED) { - printf("%s:%d: file '%s' is already sourced from '%s'\n", - zconf_curname(), zconf_lineno(), name, - file->parent->name); - exit(1); + for (iter = current_file->parent; iter; iter = iter->parent ) { + if (!strcmp(current_file->name,iter->name) ) { + printf("%s:%d: recursive inclusion detected. " + "Inclusion path:\n current file : '%s'\n", + zconf_curname(), zconf_lineno(), + zconf_curname()); + iter = current_file->parent; + while (iter && \ + strcmp(iter->name,current_file->name)) { + printf(" included from: '%s:%d'\n", + iter->name, iter->lineno-1); + iter = iter->parent; + } + if (iter) + printf(" included from: '%s:%d'\n", + iter->name, iter->lineno+1); + exit(1); + } } file->flags |= FILE_BUSY; file->lineno = 1; diff --git a/scripts/kconfig/zconf.l b/scripts/kconfig/zconf.l index 3dbaec185cc4..f23e3affa9b5 100644 --- a/scripts/kconfig/zconf.l +++ b/scripts/kconfig/zconf.l @@ -299,6 +299,7 @@ void zconf_initscan(const char *name) void zconf_nextfile(const char *name) { + struct file *iter; struct file *file = file_lookup(name); struct buffer *buf = malloc(sizeof(*buf)); memset(buf, 0, sizeof(*buf)); @@ -314,16 +315,24 @@ void zconf_nextfile(const char *name) buf->parent = current_buf; current_buf = buf; - if (file->flags & FILE_BUSY) { - printf("%s:%d: do not source '%s' from itself\n", - zconf_curname(), zconf_lineno(), name); - exit(1); - } - if (file->flags & FILE_SCANNED) { - printf("%s:%d: file '%s' is already sourced from '%s'\n", - zconf_curname(), zconf_lineno(), name, - file->parent->name); - exit(1); + for (iter = current_file->parent; iter; iter = iter->parent ) { + if (!strcmp(current_file->name,iter->name) ) { + printf("%s:%d: recursive inclusion detected. " + "Inclusion path:\n current file : '%s'\n", + zconf_curname(), zconf_lineno(), + zconf_curname()); + iter = current_file->parent; + while (iter && \ + strcmp(iter->name,current_file->name)) { + printf(" included from: '%s:%d'\n", + iter->name, iter->lineno-1); + iter = iter->parent; + } + if (iter) + printf(" included from: '%s:%d'\n", + iter->name, iter->lineno+1); + exit(1); + } } file->flags |= FILE_BUSY; file->lineno = 1; -- cgit v1.2.3-71-gd317 From 2b2112f617e8ca600ec24271c93bbd49aa2acce4 Mon Sep 17 00:00:00 2001 From: "Yann E. MORIN" Date: Thu, 24 Feb 2011 19:36:43 +0100 Subject: kconfig: get rid of unused flags Now that we detect recusrion of sourced files, get rid of now unused flags. Regenerate lex.zconf.c_shipped file. Signed-off-by: "Yann E. MORIN" Signed-off-by: Michal Marek --- scripts/kconfig/expr.h | 4 ---- scripts/kconfig/lex.zconf.c_shipped | 4 ---- scripts/kconfig/zconf.l | 4 ---- 3 files changed, 12 deletions(-) (limited to 'scripts') diff --git a/scripts/kconfig/expr.h b/scripts/kconfig/expr.h index 3d238db49764..16bfae2d3217 100644 --- a/scripts/kconfig/expr.h +++ b/scripts/kconfig/expr.h @@ -20,12 +20,8 @@ struct file { struct file *parent; const char *name; int lineno; - int flags; }; -#define FILE_BUSY 0x0001 -#define FILE_SCANNED 0x0002 - typedef enum tristate { no, mod, yes } tristate; diff --git a/scripts/kconfig/lex.zconf.c_shipped b/scripts/kconfig/lex.zconf.c_shipped index f4b3b1a15e21..d9182916f724 100644 --- a/scripts/kconfig/lex.zconf.c_shipped +++ b/scripts/kconfig/lex.zconf.c_shipped @@ -2363,7 +2363,6 @@ void zconf_initscan(const char *name) current_file = file_lookup(name); current_file->lineno = 1; - current_file->flags = FILE_BUSY; } void zconf_nextfile(const char *name) @@ -2403,7 +2402,6 @@ void zconf_nextfile(const char *name) exit(1); } } - file->flags |= FILE_BUSY; file->lineno = 1; file->parent = current_file; current_file = file; @@ -2413,8 +2411,6 @@ static void zconf_endfile(void) { struct buffer *parent; - current_file->flags |= FILE_SCANNED; - current_file->flags &= ~FILE_BUSY; current_file = current_file->parent; parent = current_buf->parent; diff --git a/scripts/kconfig/zconf.l b/scripts/kconfig/zconf.l index f23e3affa9b5..b22f884f9022 100644 --- a/scripts/kconfig/zconf.l +++ b/scripts/kconfig/zconf.l @@ -294,7 +294,6 @@ void zconf_initscan(const char *name) current_file = file_lookup(name); current_file->lineno = 1; - current_file->flags = FILE_BUSY; } void zconf_nextfile(const char *name) @@ -334,7 +333,6 @@ void zconf_nextfile(const char *name) exit(1); } } - file->flags |= FILE_BUSY; file->lineno = 1; file->parent = current_file; current_file = file; @@ -344,8 +342,6 @@ static void zconf_endfile(void) { struct buffer *parent; - current_file->flags |= FILE_SCANNED; - current_file->flags &= ~FILE_BUSY; current_file = current_file->parent; parent = current_buf->parent; -- cgit v1.2.3-71-gd317 From c33724a43875786719f51916311308f2752d846e Mon Sep 17 00:00:00 2001 From: Michal Marek Date: Tue, 28 Apr 2009 15:05:20 +0200 Subject: kconfig: Do not record timestamp in auto.conf and autoconf.h Timestamps in file data are useless and there is already one in .config Signed-off-by: Michal Marek --- scripts/kconfig/confdata.c | 8 ++------ 1 file changed, 2 insertions(+), 6 deletions(-) (limited to 'scripts') diff --git a/scripts/kconfig/confdata.c b/scripts/kconfig/confdata.c index 61c35bf2d9cb..834eecb010ba 100644 --- a/scripts/kconfig/confdata.c +++ b/scripts/kconfig/confdata.c @@ -784,7 +784,6 @@ int conf_write_autoconf(void) const char *str; const char *name; FILE *out, *tristate, *out_h; - time_t now; int i; sym_clear_all_valid(); @@ -811,22 +810,19 @@ int conf_write_autoconf(void) return 1; } - time(&now); fprintf(out, "#\n" "# Automatically generated make config: don't edit\n" "# %s\n" - "# %s" "#\n", - rootmenu.prompt->text, ctime(&now)); + rootmenu.prompt->text); fprintf(tristate, "#\n" "# Automatically generated - do not edit\n" "\n"); fprintf(out_h, "/*\n" " * Automatically generated C config: don't edit\n" " * %s\n" - " * %s" " */\n", - rootmenu.prompt->text, ctime(&now)); + rootmenu.prompt->text); for_all_symbols(i, sym) { sym_calc_value(sym); -- cgit v1.2.3-71-gd317 From 6ae9ecb86188cc8419024cdb299f18d4ae4f5713 Mon Sep 17 00:00:00 2001 From: Michal Marek Date: Thu, 31 Mar 2011 15:47:55 +0200 Subject: kbuild: Call gzip with -n The timestamps recorded in the .gz files add no value. Signed-off-by: Michal Marek --- scripts/Makefile.lib | 2 +- scripts/gen_initramfs_list.sh | 4 ++-- 2 files changed, 3 insertions(+), 3 deletions(-) (limited to 'scripts') diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib index 1c702ca8aac8..93b2b5938a2e 100644 --- a/scripts/Makefile.lib +++ b/scripts/Makefile.lib @@ -197,7 +197,7 @@ cmd_objcopy = $(OBJCOPY) $(OBJCOPYFLAGS) $(OBJCOPYFLAGS_$(@F)) $< $@ # --------------------------------------------------------------------------- quiet_cmd_gzip = GZIP $@ -cmd_gzip = (cat $(filter-out FORCE,$^) | gzip -f -9 > $@) || \ +cmd_gzip = (cat $(filter-out FORCE,$^) | gzip -n -f -9 > $@) || \ (rm -f $@ ; false) # DTC diff --git a/scripts/gen_initramfs_list.sh b/scripts/gen_initramfs_list.sh index 55caecdad995..4a43fe12d179 100644 --- a/scripts/gen_initramfs_list.sh +++ b/scripts/gen_initramfs_list.sh @@ -226,7 +226,7 @@ cpio_list= output="/dev/stdout" output_file="" is_cpio_compressed= -compr="gzip -9 -f" +compr="gzip -n -9 -f" arg="$1" case "$arg" in @@ -240,7 +240,7 @@ case "$arg" in output_file="$1" cpio_list="$(mktemp ${TMPDIR:-/tmp}/cpiolist.XXXXXX)" output=${cpio_list} - echo "$output_file" | grep -q "\.gz$" && compr="gzip -9 -f" + echo "$output_file" | grep -q "\.gz$" && compr="gzip -n -9 -f" echo "$output_file" | grep -q "\.bz2$" && compr="bzip2 -9 -f" echo "$output_file" | grep -q "\.lzma$" && compr="lzma -9 -f" echo "$output_file" | grep -q "\.xz$" && \ -- cgit v1.2.3-71-gd317 From 09ff9fecc039d60fff6c11d47522af61e89fff56 Mon Sep 17 00:00:00 2001 From: Michal Marek Date: Thu, 31 Mar 2011 16:09:47 +0200 Subject: kbuild: Use the deterministic mode of ar Signed-off-by: Michal Marek --- scripts/Makefile.build | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'scripts') diff --git a/scripts/Makefile.build b/scripts/Makefile.build index d5f925abe4d2..5f87d3709f9f 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -345,7 +345,7 @@ quiet_cmd_link_o_target = LD $@ cmd_link_o_target = $(if $(strip $(obj-y)),\ $(LD) $(ld_flags) -r -o $@ $(filter $(obj-y), $^) \ $(cmd_secanalysis),\ - rm -f $@; $(AR) rcs $@) + rm -f $@; $(AR) rcsD $@) $(builtin-target): $(obj-y) FORCE $(call if_changed,link_o_target) @@ -371,7 +371,7 @@ $(modorder-target): $(subdir-ym) FORCE # ifdef lib-target quiet_cmd_link_l_target = AR $@ -cmd_link_l_target = rm -f $@; $(AR) rcs $@ $(lib-y) +cmd_link_l_target = rm -f $@; $(AR) rcsD $@ $(lib-y) $(lib-target): $(lib-y) FORCE $(call if_changed,link_l_target) -- cgit v1.2.3-71-gd317 From 061296dc2c14f852604fc6849669fe0b78bb1eda Mon Sep 17 00:00:00 2001 From: Michal Marek Date: Thu, 31 Mar 2011 17:13:55 +0200 Subject: kbuild: Drop unused LINUX_COMPILE_TIME and LINUX_COMPILE_DOMAIN macros Signed-off-by: Michal Marek --- scripts/mkcompile_h | 16 ++-------------- 1 file changed, 2 insertions(+), 14 deletions(-) (limited to 'scripts') diff --git a/scripts/mkcompile_h b/scripts/mkcompile_h index 50ad317a4bf9..82416a81df5e 100755 --- a/scripts/mkcompile_h +++ b/scripts/mkcompile_h @@ -63,21 +63,9 @@ UTS_TRUNCATE="cut -b -$UTS_LEN" echo \#define UTS_VERSION \"`echo $UTS_VERSION | $UTS_TRUNCATE`\" - echo \#define LINUX_COMPILE_TIME \"`date +%T`\" echo \#define LINUX_COMPILE_BY \"`whoami`\" echo \#define LINUX_COMPILE_HOST \"`hostname | $UTS_TRUNCATE`\" - domain=`dnsdomainname 2> /dev/null` - if [ -z "$domain" ]; then - domain=`domainname 2> /dev/null` - fi - - if [ -n "$domain" ]; then - echo \#define LINUX_COMPILE_DOMAIN \"`echo $domain | $UTS_TRUNCATE`\" - else - echo \#define LINUX_COMPILE_DOMAIN - fi - echo \#define LINUX_COMPILER \"`$CC -v 2>&1 | tail -n 1`\" ) > .tmpcompile @@ -91,8 +79,8 @@ UTS_TRUNCATE="cut -b -$UTS_LEN" # first line. if [ -r $TARGET ] && \ - grep -v 'UTS_VERSION\|LINUX_COMPILE_TIME' $TARGET > .tmpver.1 && \ - grep -v 'UTS_VERSION\|LINUX_COMPILE_TIME' .tmpcompile > .tmpver.2 && \ + grep -v 'UTS_VERSION' $TARGET > .tmpver.1 && \ + grep -v 'UTS_VERSION' .tmpcompile > .tmpver.2 && \ cmp -s .tmpver.1 .tmpver.2; then rm -f .tmpcompile else -- cgit v1.2.3-71-gd317 From 53e6892c0411006848882eacfcfea9e93681b55d Mon Sep 17 00:00:00 2001 From: Michal Marek Date: Tue, 5 Apr 2011 14:32:30 +0200 Subject: kbuild: Allow to override LINUX_COMPILE_BY and LINUX_COMPILE_HOST macros Make it possible to override the user@host string displayed during boot and in /proc/version by the environment variables KBUILD_BUILD_USER and KBUILD_BUILD_HOST. Several distributions patch scripts/mkcompile_h to achieve this, so let's provide an official way. Also, document the KBUILD_BUILD_TIMESTAMP variable while at it. Signed-off-by: Michal Marek --- Documentation/kbuild/kbuild.txt | 12 ++++++++++++ scripts/mkcompile_h | 14 ++++++++++++-- 2 files changed, 24 insertions(+), 2 deletions(-) (limited to 'scripts') diff --git a/Documentation/kbuild/kbuild.txt b/Documentation/kbuild/kbuild.txt index f1431d099fce..f11ebb33e4a6 100644 --- a/Documentation/kbuild/kbuild.txt +++ b/Documentation/kbuild/kbuild.txt @@ -201,3 +201,15 @@ KBUILD_ENABLE_EXTRA_GCC_CHECKS -------------------------------------------------- If enabled over the make command line with "W=1", it turns on additional gcc -W... options for more extensive build-time checking. + +KBUILD_BUILD_TIMESTAMP +-------------------------------------------------- +Setting this to a date string overrides the timestamp used in the +UTS_VERSION definition (uname -v in the running kernel). The default value +is the output of the date command at one point during build. + +KBUILD_BUILD_USER, KBUILD_BUILD_HOST +-------------------------------------------------- +These two variables allow to override the user@host string displayed during +boot and in /proc/version. The default value is the output of the commands +whoami and host, respectively. diff --git a/scripts/mkcompile_h b/scripts/mkcompile_h index 82416a81df5e..7ad6bf7a09ff 100755 --- a/scripts/mkcompile_h +++ b/scripts/mkcompile_h @@ -42,6 +42,16 @@ if [ -z "$KBUILD_BUILD_TIMESTAMP" ]; then else TIMESTAMP=$KBUILD_BUILD_TIMESTAMP fi +if test -z "$KBUILD_BUILD_USER"; then + LINUX_COMPILE_BY=`whoami` +else + LINUX_COMPILE_BY=$KBUILD_BUILD_USER +fi +if test -z "$KBUILD_BUILD_HOST"; then + LINUX_COMPILE_HOST=`hostname` +else + LINUX_COMPILE_HOST=$KBUILD_BUILD_HOST +fi UTS_VERSION="#$VERSION" CONFIG_FLAGS="" @@ -63,8 +73,8 @@ UTS_TRUNCATE="cut -b -$UTS_LEN" echo \#define UTS_VERSION \"`echo $UTS_VERSION | $UTS_TRUNCATE`\" - echo \#define LINUX_COMPILE_BY \"`whoami`\" - echo \#define LINUX_COMPILE_HOST \"`hostname | $UTS_TRUNCATE`\" + echo \#define LINUX_COMPILE_BY \"`echo $LINUX_COMPILE_BY | $UTS_TRUNCATE`\" + echo \#define LINUX_COMPILE_HOST \"`echo $LINUX_COMPILE_HOST | $UTS_TRUNCATE`\" echo \#define LINUX_COMPILER \"`$CC -v 2>&1 | tail -n 1`\" ) > .tmpcompile -- cgit v1.2.3-71-gd317 From a8b8017c34fefcb763d8b06c294b58d1c480b2e4 Mon Sep 17 00:00:00 2001 From: Michal Marek Date: Thu, 31 Mar 2011 23:16:42 +0200 Subject: initramfs: Use KBUILD_BUILD_TIMESTAMP for generated entries gen_init_cpio gets the current time and uses it for each symlink, special file, and directory. Grab the current time once and make it possible to override it with the KBUILD_BUILD_TIMESTAMP variable for reproducible builds. Signed-off-by: Michal Marek --- Documentation/kbuild/kbuild.txt | 3 ++- scripts/gen_initramfs_list.sh | 9 ++++++- usr/gen_init_cpio.c | 53 +++++++++++++++++++++++++++++++---------- 3 files changed, 50 insertions(+), 15 deletions(-) (limited to 'scripts') diff --git a/Documentation/kbuild/kbuild.txt b/Documentation/kbuild/kbuild.txt index f11ebb33e4a6..646e2c114fff 100644 --- a/Documentation/kbuild/kbuild.txt +++ b/Documentation/kbuild/kbuild.txt @@ -205,7 +205,8 @@ gcc -W... options for more extensive build-time checking. KBUILD_BUILD_TIMESTAMP -------------------------------------------------- Setting this to a date string overrides the timestamp used in the -UTS_VERSION definition (uname -v in the running kernel). The default value +UTS_VERSION definition (uname -v in the running kernel). The value has to +be a string that can be passed to date -d. The default value is the output of the date command at one point during build. KBUILD_BUILD_USER, KBUILD_BUILD_HOST diff --git a/scripts/gen_initramfs_list.sh b/scripts/gen_initramfs_list.sh index 4a43fe12d179..d44cf675bc22 100644 --- a/scripts/gen_initramfs_list.sh +++ b/scripts/gen_initramfs_list.sh @@ -287,8 +287,15 @@ done # we are carefull to delete tmp files if [ ! -z ${output_file} ]; then if [ -z ${cpio_file} ]; then + timestamp= + if test -n "$KBUILD_BUILD_TIMESTAMP"; then + timestamp="$(date -d"$KBUILD_BUILD_TIMESTAMP" +%s || :)" + if test -n "$timestamp"; then + timestamp="-t $timestamp" + fi + fi cpio_tfile="$(mktemp ${TMPDIR:-/tmp}/cpiofile.XXXXXX)" - usr/gen_init_cpio ${cpio_list} > ${cpio_tfile} + usr/gen_init_cpio $timestamp ${cpio_list} > ${cpio_tfile} else cpio_tfile=${cpio_file} fi diff --git a/usr/gen_init_cpio.c b/usr/gen_init_cpio.c index 7f06884ecd41..af0f22fb1ef7 100644 --- a/usr/gen_init_cpio.c +++ b/usr/gen_init_cpio.c @@ -22,6 +22,7 @@ static unsigned int offset; static unsigned int ino = 721; +static time_t default_mtime; struct file_handler { const char *type; @@ -102,7 +103,6 @@ static int cpio_mkslink(const char *name, const char *target, unsigned int mode, uid_t uid, gid_t gid) { char s[256]; - time_t mtime = time(NULL); if (name[0] == '/') name++; @@ -114,7 +114,7 @@ static int cpio_mkslink(const char *name, const char *target, (long) uid, /* uid */ (long) gid, /* gid */ 1, /* nlink */ - (long) mtime, /* mtime */ + (long) default_mtime, /* mtime */ (unsigned)strlen(target)+1, /* filesize */ 3, /* major */ 1, /* minor */ @@ -152,7 +152,6 @@ static int cpio_mkgeneric(const char *name, unsigned int mode, uid_t uid, gid_t gid) { char s[256]; - time_t mtime = time(NULL); if (name[0] == '/') name++; @@ -164,7 +163,7 @@ static int cpio_mkgeneric(const char *name, unsigned int mode, (long) uid, /* uid */ (long) gid, /* gid */ 2, /* nlink */ - (long) mtime, /* mtime */ + (long) default_mtime, /* mtime */ 0, /* filesize */ 3, /* major */ 1, /* minor */ @@ -242,7 +241,6 @@ static int cpio_mknod(const char *name, unsigned int mode, unsigned int maj, unsigned int min) { char s[256]; - time_t mtime = time(NULL); if (dev_type == 'b') mode |= S_IFBLK; @@ -259,7 +257,7 @@ static int cpio_mknod(const char *name, unsigned int mode, (long) uid, /* uid */ (long) gid, /* gid */ 1, /* nlink */ - (long) mtime, /* mtime */ + (long) default_mtime, /* mtime */ 0, /* filesize */ 3, /* major */ 1, /* minor */ @@ -460,7 +458,7 @@ static int cpio_mkfile_line(const char *line) static void usage(const char *prog) { fprintf(stderr, "Usage:\n" - "\t%s \n" + "\t%s [-t ] \n" "\n" " is a file containing newline separated entries that\n" "describe the files to be included in the initramfs archive:\n" @@ -491,7 +489,11 @@ static void usage(const char *prog) "nod /dev/console 0600 0 0 c 5 1\n" "dir /root 0700 0 0\n" "dir /sbin 0755 0 0\n" - "file /sbin/kinit /usr/src/klibc/kinit/kinit 0755 0 0\n", + "file /sbin/kinit /usr/src/klibc/kinit/kinit 0755 0 0\n" + "\n" + " is time in seconds since Epoch that will be used\n" + "as mtime for symlinks, special files and directories. The default\n" + "is to use the current time for these entries.\n", prog); } @@ -529,17 +531,42 @@ int main (int argc, char *argv[]) char *args, *type; int ec = 0; int line_nr = 0; + const char *filename; + + default_mtime = time(NULL); + while (1) { + int opt = getopt(argc, argv, "t:h"); + char *invalid; - if (2 != argc) { + if (opt == -1) + break; + switch (opt) { + case 't': + default_mtime = strtol(optarg, &invalid, 10); + if (!*optarg || *invalid) { + fprintf(stderr, "Invalid timestamp: %s\n", + optarg); + usage(argv[0]); + exit(1); + } + break; + case 'h': + case '?': + usage(argv[0]); + exit(opt == 'h' ? 0 : 1); + } + } + + if (argc - optind != 1) { usage(argv[0]); exit(1); } - - if (!strcmp(argv[1], "-")) + filename = argv[optind]; + if (!strcmp(filename, "-")) cpio_list = stdin; - else if (! (cpio_list = fopen(argv[1], "r"))) { + else if (!(cpio_list = fopen(filename, "r"))) { fprintf(stderr, "ERROR: unable to open '%s': %s\n\n", - argv[1], strerror(errno)); + filename, strerror(errno)); usage(argv[0]); exit(1); } -- cgit v1.2.3-71-gd317 From 10175ba65fde4b3708b9dd338af4b2dfb6bf266d Mon Sep 17 00:00:00 2001 From: Stephen Boyd Date: Wed, 6 Apr 2011 15:07:49 -0700 Subject: nconfig: Silence unused return values from wattrset Ignore the return value from wattrset since we ignore the return value in nconf.gui.c as well. scripts/kconfig/nconf.c: In function 'print_function_line': scripts/kconfig/nconf.c:376: warning: value computed is not used scripts/kconfig/nconf.c:380: warning: value computed is not used scripts/kconfig/nconf.c:387: warning: value computed is not used scripts/kconfig/nconf.c: In function 'show_menu': scripts/kconfig/nconf.c:956: warning: value computed is not used scripts/kconfig/nconf.c:961: warning: value computed is not used scripts/kconfig/nconf.c:963: warning: value computed is not used scripts/kconfig/nconf.c:965: warning: value computed is not used Cc: Nir Tzachar Signed-off-by: Stephen Boyd Signed-off-by: Michal Marek --- scripts/kconfig/nconf.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) (limited to 'scripts') diff --git a/scripts/kconfig/nconf.c b/scripts/kconfig/nconf.c index db56377393d7..488dd7410787 100644 --- a/scripts/kconfig/nconf.c +++ b/scripts/kconfig/nconf.c @@ -373,18 +373,18 @@ static void print_function_line(void) const int skip = 1; for (i = 0; i < function_keys_num; i++) { - wattrset(main_window, attributes[FUNCTION_HIGHLIGHT]); + (void) wattrset(main_window, attributes[FUNCTION_HIGHLIGHT]); mvwprintw(main_window, LINES-3, offset, "%s", function_keys[i].key_str); - wattrset(main_window, attributes[FUNCTION_TEXT]); + (void) wattrset(main_window, attributes[FUNCTION_TEXT]); offset += strlen(function_keys[i].key_str); mvwprintw(main_window, LINES-3, offset, "%s", function_keys[i].func); offset += strlen(function_keys[i].func) + skip; } - wattrset(main_window, attributes[NORMAL]); + (void) wattrset(main_window, attributes[NORMAL]); } /* help */ @@ -953,16 +953,16 @@ static void show_menu(const char *prompt, const char *instructions, current_instructions = instructions; clear(); - wattrset(main_window, attributes[NORMAL]); + (void) wattrset(main_window, attributes[NORMAL]); print_in_middle(stdscr, 1, 0, COLS, menu_backtitle, attributes[MAIN_HEADING]); - wattrset(main_window, attributes[MAIN_MENU_BOX]); + (void) wattrset(main_window, attributes[MAIN_MENU_BOX]); box(main_window, 0, 0); - wattrset(main_window, attributes[MAIN_MENU_HEADING]); + (void) wattrset(main_window, attributes[MAIN_MENU_HEADING]); mvwprintw(main_window, 0, 3, " %s ", prompt); - wattrset(main_window, attributes[NORMAL]); + (void) wattrset(main_window, attributes[NORMAL]); set_menu_items(curses_menu, curses_menu_items); -- cgit v1.2.3-71-gd317 From 40df759e2b9ec945f1a5ddc61b3fdfbb6583257e Mon Sep 17 00:00:00 2001 From: Michal Marek Date: Wed, 20 Apr 2011 13:45:30 +0200 Subject: kbuild: Fix build with binutils <= 2.19 The D option of ar is only available in newer versions. Signed-off-by: Michal Marek --- Documentation/kbuild/makefiles.txt | 5 +++++ Makefile | 4 ++++ scripts/Kbuild.include | 5 +++++ scripts/Makefile.build | 4 ++-- 4 files changed, 16 insertions(+), 2 deletions(-) (limited to 'scripts') diff --git a/Documentation/kbuild/makefiles.txt b/Documentation/kbuild/makefiles.txt index 5d145bb443c0..40e082bb8c52 100644 --- a/Documentation/kbuild/makefiles.txt +++ b/Documentation/kbuild/makefiles.txt @@ -955,6 +955,11 @@ When kbuild executes, the following steps are followed (roughly): used when linking modules. This is often a linker script. From commandline LDFLAGS_MODULE shall be used (see kbuild.txt). + KBUILD_ARFLAGS Options for $(AR) when creating archives + + $(KBUILD_ARFLAGS) set by the top level Makefile to "D" (deterministic + mode) if this option is supported by $(AR). + --- 6.2 Add prerequisites to archprepare: The archprepare: rule is used to list prerequisites that need to be diff --git a/Makefile b/Makefile index c3bd316b16f4..d7c42319fe1e 100644 --- a/Makefile +++ b/Makefile @@ -382,6 +382,7 @@ export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE CFLAGS_GCOV export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_LDFLAGS_MODULE export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL +export KBUILD_ARFLAGS # When compiling out-of-tree modules, put MODVERDIR in the module # tree rather than in the kernel tree. The kernel tree might @@ -612,6 +613,9 @@ KBUILD_CFLAGS += $(call cc-option,-fno-strict-overflow) # conserve stack if available KBUILD_CFLAGS += $(call cc-option,-fconserve-stack) +# use the deterministic mode of AR if available +KBUILD_ARFLAGS := $(call ar-option,D) + # check for 'asm goto' ifeq ($(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-goto.sh $(CC)), y) KBUILD_CFLAGS += -DCC_HAVE_ASM_GOTO diff --git a/scripts/Kbuild.include b/scripts/Kbuild.include index ed2773edfe71..fae2d8d8cb09 100644 --- a/scripts/Kbuild.include +++ b/scripts/Kbuild.include @@ -141,6 +141,11 @@ cc-ldoption = $(call try-run,\ ld-option = $(call try-run,\ $(CC) /dev/null -c -o "$$TMPO" ; $(LD) $(1) "$$TMPO" -o "$$TMP",$(1),$(2)) +# ar-option +# Usage: KBUILD_ARFLAGS := $(call ar-option,D) +# Important: no spaces around options +ar-option = $(call try-run, $(AR) rc$(1) "$$TMP",$(1),$(2)) + ###### ### diff --git a/scripts/Makefile.build b/scripts/Makefile.build index 5f87d3709f9f..e1244ef308ce 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -345,7 +345,7 @@ quiet_cmd_link_o_target = LD $@ cmd_link_o_target = $(if $(strip $(obj-y)),\ $(LD) $(ld_flags) -r -o $@ $(filter $(obj-y), $^) \ $(cmd_secanalysis),\ - rm -f $@; $(AR) rcsD $@) + rm -f $@; $(AR) rcs$(KBUILD_ARFLAGS) $@) $(builtin-target): $(obj-y) FORCE $(call if_changed,link_o_target) @@ -371,7 +371,7 @@ $(modorder-target): $(subdir-ym) FORCE # ifdef lib-target quiet_cmd_link_l_target = AR $@ -cmd_link_l_target = rm -f $@; $(AR) rcsD $@ $(lib-y) +cmd_link_l_target = rm -f $@; $(AR) rcs$(KBUILD_ARFLAGS) $@ $(lib-y) $(lib-target): $(lib-y) FORCE $(call if_changed,link_l_target) -- cgit v1.2.3-71-gd317 From 28bc20dccadc610c56e27255aeef2938141a0cd3 Mon Sep 17 00:00:00 2001 From: Sam Ravnborg Date: Wed, 27 Apr 2011 22:15:27 +0200 Subject: kbuild: implement several W= levels Building a kernel with "make W=1" produces far too much noise to be useful. Divide the warning options in three groups: W=1 - warnings that may be relevant and does not occur too often W=2 - warnings that occur quite often but may still be relevant W=3 - the more obscure warnings, can most likely be ignored When building the whole kernel, those levels produce: W=1 - 4859 warnings W=2 - 1394 warnings W=3 - 86666 warnings respectively. Warnings have been counted with Geert's script at http://www.kernel.org/pub/linux/kernel/people/geert/linux-log/linux-log-summary.pl Many warnings occur from .h files so fixing one file may have a nice effect on the total number of warnings. With these changes I am actually tempted to try W=1 now and then. Previously there was just too much noise. Borislav: - make the W= levels exclusive - move very noisy and making little sense for the kernel warnings to W=3 - drop -Woverlength-strings due to useless warning message - copy explanatory text for the different warning levels to 'make help' - recount warnings per level Signed-off-by: Sam Ravnborg Signed-off-by: Borislav Petkov Cc: Dave Jones Cc: Geert Uytterhoeven Signed-off-by: Michal Marek --- Makefile | 8 +++++-- scripts/Makefile.build | 65 +++++++++++++++++++++++++++++--------------------- 2 files changed, 44 insertions(+), 29 deletions(-) (limited to 'scripts') diff --git a/Makefile b/Makefile index d7c42319fe1e..d43429f4ced8 100644 --- a/Makefile +++ b/Makefile @@ -103,7 +103,7 @@ ifeq ("$(origin O)", "command line") endif ifeq ("$(origin W)", "command line") - export KBUILD_ENABLE_EXTRA_GCC_CHECKS := 1 + export KBUILD_ENABLE_EXTRA_GCC_CHECKS := $(W) endif # That's our default target when none is given on the command line @@ -1274,7 +1274,11 @@ help: @echo ' make O=dir [targets] Locate all output files in "dir", including .config' @echo ' make C=1 [targets] Check all c source with $$CHECK (sparse by default)' @echo ' make C=2 [targets] Force check of all c source with $$CHECK' - @echo ' make W=1 [targets] Enable extra gcc checks' + @echo ' make W=n [targets] Enable extra gcc checks, n=1,2,3 where' + @echo ' 1: warnings which may be relevant and do not occur too often' + @echo ' 2: warnings which occur quite often but may still be relevant' + @echo ' 3: more obscure warnings, can most likely be ignored' + @echo '' @echo 'Execute "make" or "make all" to build all targets marked with [*] ' @echo 'For further info see the ./README file' diff --git a/scripts/Makefile.build b/scripts/Makefile.build index e1244ef308ce..9c0c48127946 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -51,36 +51,47 @@ ifeq ($(KBUILD_NOPEDANTIC),) endif # -# make W=1 settings +# make W=... settings # -# $(call cc-option... ) handles gcc -W.. options which +# W=1 - warnings that may be relevant and does not occur too often +# W=2 - warnings that occur quite often but may still be relevant +# W=3 - the more obscure warnings, can most likely be ignored +# +# $(call cc-option, -W...) handles gcc -W.. options which # are not supported by all versions of the compiler ifdef KBUILD_ENABLE_EXTRA_GCC_CHECKS -KBUILD_EXTRA_WARNINGS := -Wextra -KBUILD_EXTRA_WARNINGS += -Wunused -Wno-unused-parameter -KBUILD_EXTRA_WARNINGS += -Waggregate-return -KBUILD_EXTRA_WARNINGS += -Wbad-function-cast -KBUILD_EXTRA_WARNINGS += -Wcast-qual -KBUILD_EXTRA_WARNINGS += -Wcast-align -KBUILD_EXTRA_WARNINGS += -Wconversion -KBUILD_EXTRA_WARNINGS += -Wdisabled-optimization -KBUILD_EXTRA_WARNINGS += -Wlogical-op -KBUILD_EXTRA_WARNINGS += -Wmissing-declarations -KBUILD_EXTRA_WARNINGS += -Wmissing-format-attribute -KBUILD_EXTRA_WARNINGS += $(call cc-option, -Wmissing-include-dirs,) -KBUILD_EXTRA_WARNINGS += -Wmissing-prototypes -KBUILD_EXTRA_WARNINGS += -Wnested-externs -KBUILD_EXTRA_WARNINGS += -Wold-style-definition -KBUILD_EXTRA_WARNINGS += $(call cc-option, -Woverlength-strings,) -KBUILD_EXTRA_WARNINGS += -Wpacked -KBUILD_EXTRA_WARNINGS += -Wpacked-bitfield-compat -KBUILD_EXTRA_WARNINGS += -Wpadded -KBUILD_EXTRA_WARNINGS += -Wpointer-arith -KBUILD_EXTRA_WARNINGS += -Wredundant-decls -KBUILD_EXTRA_WARNINGS += -Wshadow -KBUILD_EXTRA_WARNINGS += -Wswitch-default -KBUILD_EXTRA_WARNINGS += $(call cc-option, -Wvla,) -KBUILD_CFLAGS += $(KBUILD_EXTRA_WARNINGS) +warning-1 := -Wextra -Wunused -Wno-unused-parameter +warning-1 += -Wmissing-declarations +warning-1 += -Wmissing-format-attribute +warning-1 += -Wmissing-prototypes +warning-1 += -Wold-style-definition +warning-1 += $(call cc-option, -Wmissing-include-dirs) + +warning-2 := -Waggregate-return +warning-2 += -Wcast-align +warning-2 += -Wdisabled-optimization +warning-2 += -Wnested-externs +warning-2 += -Wshadow +warning-2 += $(call cc-option, -Wlogical-op) + +warning-3 := -Wbad-function-cast +warning-3 += -Wcast-qual +warning-3 += -Wconversion +warning-3 += -Wpacked +warning-3 += -Wpadded +warning-3 += -Wpointer-arith +warning-3 += -Wredundant-decls +warning-3 += -Wswitch-default +warning-3 += $(call cc-option, -Wpacked-bitfield-compat) +warning-3 += $(call cc-option, -Wvla) + +warning := $(warning-$(KBUILD_ENABLE_EXTRA_GCC_CHECKS)) + +ifeq ("$(warning)","") + $(error W=$(KBUILD_ENABLE_EXTRA_GCC_CHECKS) is unknown) +endif + +KBUILD_CFLAGS += $(warning) endif include scripts/Makefile.lib -- cgit v1.2.3-71-gd317 From d8ecc5cd8e227bc318513b5306ae88a474b8886d Mon Sep 17 00:00:00 2001 From: Sam Ravnborg Date: Wed, 27 Apr 2011 22:29:49 +0200 Subject: kbuild: asm-generic support There is an increasing amount of header files shared between individual architectures in asm-generic. To avoid a lot of dummy wrapper files that just include the corresponding file in asm-generic provide some basic support in kbuild for this. With the following patch an architecture can maintain a list of files in the file arch/$(ARCH)/include/asm/Kbuild To use a generic file just add: generic-y += For each file listed kbuild will generate the necessary wrapper in arch/$(ARCH)/include/generated/asm. When installing userspace headers a wrapper is likewise created. The original inspiration for this came from the unicore32 patchset - although a different method is used. The patch includes several improvements from Arnd Bergmann. Michael Marek contributed Makefile.asm-generic. Remis Baima did an intial implementation along to achive the same - see https://patchwork.kernel.org/patch/13352/ Signed-off-by: Sam Ravnborg Acked-by: Guan Xuetao Tested-by: Guan Xuetao Acked-by: Arnd Bergmann Cc: Remis Lima Baima Signed-off-by: Michal Marek --- .gitignore | 1 + Documentation/kbuild/makefiles.txt | 36 ++++++++++++++++++++++++++++++++++++ Makefile | 16 ++++++++++++---- scripts/Makefile.asm-generic | 23 +++++++++++++++++++++++ scripts/Makefile.headersinst | 10 +++++++++- 5 files changed, 81 insertions(+), 5 deletions(-) create mode 100644 scripts/Makefile.asm-generic (limited to 'scripts') diff --git a/.gitignore b/.gitignore index 5d56a3fd0de6..9dacde0a4b2d 100644 --- a/.gitignore +++ b/.gitignore @@ -57,6 +57,7 @@ modules.builtin include/config include/linux/version.h include/generated +arch/*/include/generated # stgit generated dirs patches-* diff --git a/Documentation/kbuild/makefiles.txt b/Documentation/kbuild/makefiles.txt index 40e082bb8c52..835b64acf0b4 100644 --- a/Documentation/kbuild/makefiles.txt +++ b/Documentation/kbuild/makefiles.txt @@ -40,11 +40,13 @@ This document describes the Linux kernel Makefiles. --- 6.6 Commands useful for building a boot image --- 6.7 Custom kbuild commands --- 6.8 Preprocessing linker scripts + --- 6.9 Generic header files === 7 Kbuild syntax for exported headers --- 7.1 header-y --- 7.2 objhdr-y --- 7.3 destination-y + --- 7.4 generic-y === 8 Kbuild Variables === 9 Makefile language @@ -1214,6 +1216,14 @@ When kbuild executes, the following steps are followed (roughly): The kbuild infrastructure for *lds file are used in several architecture-specific files. +--- 6.9 Generic header files + + The directory include/asm-generic contains the header files + that may be shared between individual architectures. + The recommended approach how to use a generic header file is + to list the file in the Kbuild file. + See "7.4 generic-y" for further info on syntax etc. + === 7 Kbuild syntax for exported headers The kernel include a set of headers that is exported to userspace. @@ -1270,6 +1280,32 @@ See subsequent chapter for the syntax of the Kbuild file. In the example above all exported headers in the Kbuild file will be located in the directory "include/linux" when exported. + --- 7.4 generic-y + + If an architecture uses a verbatim copy of a header from + include/asm-generic then this is listed in the file + arch/$(ARCH)/include/asm/Kbuild like this: + + Example: + #arch/x86/include/asm/Kbuild + generic-y += termios.h + generic-y += rtc.h + + During the prepare phase of the build a wrapper include + file is generated in the directory: + + arch/$(ARCH)/include/generated/asm + + When a header is exported where the architecture uses + the generic header a similar wrapper is generated as part + of the set of exported headers in the directory: + + usr/include/asm + + The generated wrapper will in both cases look like the following: + + Example: termios.h + #include === 8 Kbuild Variables diff --git a/Makefile b/Makefile index d43429f4ced8..e509cc704968 100644 --- a/Makefile +++ b/Makefile @@ -349,7 +349,8 @@ CFLAGS_GCOV = -fprofile-arcs -ftest-coverage # Use LINUXINCLUDE when you must reference the include/ directory. # Needed to be compatible with the O= option -LINUXINCLUDE := -I$(srctree)/arch/$(hdr-arch)/include -Iinclude \ +LINUXINCLUDE := -I$(srctree)/arch/$(hdr-arch)/include \ + -Iarch/$(hdr-arch)/include/generated -Iinclude \ $(if $(KBUILD_SRC), -I$(srctree)/include) \ -include include/generated/autoconf.h @@ -417,6 +418,12 @@ ifneq ($(KBUILD_SRC),) $(srctree) $(objtree) $(VERSION) $(PATCHLEVEL) endif +# Support for using generic headers in asm-generic +PHONY += asm-generic +asm-generic: + $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.asm-generic \ + obj=arch/$(SRCARCH)/include/generated/asm + # To make sure we do not include .config for any of the *config targets # catch them early, and hand them over to scripts/kconfig/Makefile # It is allowed to specify more targets when calling make, including @@ -954,7 +961,7 @@ ifneq ($(KBUILD_SRC),) endif # prepare2 creates a makefile if using a separate output directory -prepare2: prepare3 outputmakefile +prepare2: prepare3 outputmakefile asm-generic prepare1: prepare2 include/linux/version.h include/generated/utsrelease.h \ include/config/auto.conf @@ -1028,7 +1035,7 @@ hdr-inst := -rR -f $(srctree)/scripts/Makefile.headersinst obj hdr-dst = $(if $(KBUILD_HEADERS), dst=include/asm-$(hdr-arch), dst=include/asm) PHONY += __headers -__headers: include/linux/version.h scripts_basic FORCE +__headers: include/linux/version.h scripts_basic asm-generic FORCE $(Q)$(MAKE) $(build)=scripts build_unifdef PHONY += headers_install_all @@ -1143,7 +1150,8 @@ CLEAN_FILES += vmlinux System.map \ .tmp_kallsyms* .tmp_version .tmp_vmlinux* .tmp_System.map # Directories & files removed with 'make mrproper' -MRPROPER_DIRS += include/config usr/include include/generated +MRPROPER_DIRS += include/config usr/include include/generated \ + arch/*/include/generated MRPROPER_FILES += .config .config.old .version .old_version \ include/linux/version.h \ Module.symvers tags TAGS cscope* GPATH GTAGS GRTAGS GSYMS diff --git a/scripts/Makefile.asm-generic b/scripts/Makefile.asm-generic new file mode 100644 index 000000000000..a687cb697e35 --- /dev/null +++ b/scripts/Makefile.asm-generic @@ -0,0 +1,23 @@ +# include/asm-generic contains a lot of files that are used +# verbatim by several architectures. +# +# This Makefile reads the file arch/$(SRCARCH)/include/asm/Kbuild +# and for each file listed in this file with generic-y creates +# a small wrapper file in $(obj) (arch/$(SRCARCH)/include/generated/asm) + +kbuild-file := $(srctree)/arch/$(SRCARCH)/include/asm/Kbuild +include $(kbuild-file) + +include scripts/Kbuild.include + +# Create output directory if not already present +_dummy := $(shell [ -d $(obj) ] || mkdir -p $(obj)) + +quiet_cmd_wrap = WRAP $@ +cmd_wrap = echo "\#include " >$@ + +all: $(patsubst %, $(obj)/%, $(generic-y)) + +$(obj)/%.h: + $(call cmd,wrap) + diff --git a/scripts/Makefile.headersinst b/scripts/Makefile.headersinst index f89cb87f5c01..a57f5bd5a13d 100644 --- a/scripts/Makefile.headersinst +++ b/scripts/Makefile.headersinst @@ -27,8 +27,13 @@ header-y := $(filter-out %/, $(header-y)) install-file := $(install)/.install check-file := $(install)/.check +# generic-y list all files an architecture uses from asm-generic +# Use this to build a list of headers which require a wrapper +wrapper-files := $(filter $(header-y), $(generic-y)) + # all headers files for this dir -all-files := $(header-y) $(objhdr-y) +header-y := $(filter-out $(generic-y), $(header-y)) +all-files := $(header-y) $(objhdr-y) $(wrapper-files) input-files := $(addprefix $(srctree)/$(obj)/,$(header-y)) \ $(addprefix $(objtree)/$(obj)/,$(objhdr-y)) output-files := $(addprefix $(install)/, $(all-files)) @@ -47,6 +52,9 @@ quiet_cmd_install = INSTALL $(printdir) ($(words $(all-files))\ cmd_install = \ $(PERL) $< $(srctree)/$(obj) $(install) $(SRCARCH) $(header-y); \ $(PERL) $< $(objtree)/$(obj) $(install) $(SRCARCH) $(objhdr-y); \ + for F in $(wrapper-files); do \ + echo "\#include " > $(install)/$$F; \ + done; \ touch $@ quiet_cmd_remove = REMOVE $(unwanted) -- cgit v1.2.3-71-gd317 From 1f594715bd26628045bf96c1211d5a90a1b51157 Mon Sep 17 00:00:00 2001 From: Peter Foley Date: Tue, 26 Apr 2011 17:57:38 -0400 Subject: kconfig: only build kxgettext when needed Signed-off-by: Peter Foley Signed-off-by: Michal Marek --- scripts/kconfig/Makefile | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) (limited to 'scripts') diff --git a/scripts/kconfig/Makefile b/scripts/kconfig/Makefile index 368ae306aee4..0f00673ee04d 100644 --- a/scripts/kconfig/Makefile +++ b/scripts/kconfig/Makefile @@ -169,7 +169,7 @@ mconf-objs := mconf.o zconf.tab.o $(lxdialog) nconf-objs := nconf.o zconf.tab.o nconf.gui.o kxgettext-objs := kxgettext.o zconf.tab.o -hostprogs-y := conf qconf gconf kxgettext +hostprogs-y := conf qconf gconf ifeq ($(MAKECMDGOALS),nconfig) hostprogs-y += nconf @@ -179,6 +179,10 @@ ifeq ($(MAKECMDGOALS),menuconfig) hostprogs-y += mconf endif +ifeq ($(MAKECMDGOALS),update-po-config) + hostprogs-y += kxgettext +endif + ifeq ($(MAKECMDGOALS),xconfig) qconf-target := 1 endif -- cgit v1.2.3-71-gd317 From f19430496a3655b6f86283af472f04fea3c6fdf8 Mon Sep 17 00:00:00 2001 From: Peter Foley Date: Tue, 26 Apr 2011 18:00:05 -0400 Subject: kconfig: change qconf to modify hostprogs-y like nconf and mconf Signed-off-by: Peter Foley Signed-off-by: Michal Marek --- scripts/kconfig/Makefile | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) (limited to 'scripts') diff --git a/scripts/kconfig/Makefile b/scripts/kconfig/Makefile index 0f00673ee04d..532cb6559ce5 100644 --- a/scripts/kconfig/Makefile +++ b/scripts/kconfig/Makefile @@ -168,8 +168,10 @@ conf-objs := conf.o zconf.tab.o mconf-objs := mconf.o zconf.tab.o $(lxdialog) nconf-objs := nconf.o zconf.tab.o nconf.gui.o kxgettext-objs := kxgettext.o zconf.tab.o +qconf-cxxobjs := qconf.o +qconf-objs := kconfig_load.o zconf.tab.o -hostprogs-y := conf qconf gconf +hostprogs-y := conf gconf ifeq ($(MAKECMDGOALS),nconfig) hostprogs-y += nconf @@ -192,8 +194,7 @@ endif ifeq ($(qconf-target),1) -qconf-cxxobjs := qconf.o -qconf-objs := kconfig_load.o zconf.tab.o + hostprogs-y += qconf endif ifeq ($(gconf-target),1) -- cgit v1.2.3-71-gd317 From d02ab886dcc7349cc5d80a045725d3dc9b309a3a Mon Sep 17 00:00:00 2001 From: Peter Foley Date: Tue, 26 Apr 2011 18:02:08 -0400 Subject: kconfig: change gconf to modify hostprogs-y like nconf and mconf Signed-off-by: Peter Foley Signed-off-by: Michal Marek --- scripts/kconfig/Makefile | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'scripts') diff --git a/scripts/kconfig/Makefile b/scripts/kconfig/Makefile index 532cb6559ce5..259ac37342d1 100644 --- a/scripts/kconfig/Makefile +++ b/scripts/kconfig/Makefile @@ -170,8 +170,9 @@ nconf-objs := nconf.o zconf.tab.o nconf.gui.o kxgettext-objs := kxgettext.o zconf.tab.o qconf-cxxobjs := qconf.o qconf-objs := kconfig_load.o zconf.tab.o +gconf-objs := gconf.o kconfig_load.o zconf.tab.o -hostprogs-y := conf gconf +hostprogs-y := conf ifeq ($(MAKECMDGOALS),nconfig) hostprogs-y += nconf @@ -198,7 +199,7 @@ ifeq ($(qconf-target),1) endif ifeq ($(gconf-target),1) -gconf-objs := gconf.o kconfig_load.o zconf.tab.o + hostprogs-y += gconf endif clean-files := lkc_defs.h qconf.moc .tmp_qtcheck \ -- cgit v1.2.3-71-gd317 From b24d7d7b98f2697173542fd926f48617649b0bbc Mon Sep 17 00:00:00 2001 From: Peter Foley Date: Tue, 26 Apr 2011 18:06:55 -0400 Subject: kconfig: rearrange clean-files Signed-off-by: Peter Foley Signed-off-by: Michal Marek --- scripts/kconfig/Makefile | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'scripts') diff --git a/scripts/kconfig/Makefile b/scripts/kconfig/Makefile index 259ac37342d1..cd6042ce4953 100644 --- a/scripts/kconfig/Makefile +++ b/scripts/kconfig/Makefile @@ -202,8 +202,8 @@ ifeq ($(gconf-target),1) hostprogs-y += gconf endif -clean-files := lkc_defs.h qconf.moc .tmp_qtcheck \ - .tmp_gtkcheck zconf.tab.c lex.zconf.c zconf.hash.c gconf.glade.h +clean-files := lkc_defs.h qconf.moc .tmp_qtcheck .tmp_gtkcheck +clean-files += zconf.tab.c lex.zconf.c zconf.hash.c gconf.glade.h clean-files += mconf qconf gconf nconf clean-files += config.pot linux.pot -- cgit v1.2.3-71-gd317 From a24a1b8e2aef10e8987e0a0b2b0dcff78af90ebb Mon Sep 17 00:00:00 2001 From: Peter Foley Date: Tue, 26 Apr 2011 18:13:05 -0400 Subject: kconfig: make update-po-config work in KBUILD_OUTPUT Signed-off-by: Peter Foley Signed-off-by: Michal Marek --- scripts/kconfig/Makefile | 16 +++++++++------- 1 file changed, 9 insertions(+), 7 deletions(-) (limited to 'scripts') diff --git a/scripts/kconfig/Makefile b/scripts/kconfig/Makefile index cd6042ce4953..0f6483bccbe7 100644 --- a/scripts/kconfig/Makefile +++ b/scripts/kconfig/Makefile @@ -77,14 +77,15 @@ localyesconfig: $(obj)/streamline_config.pl $(obj)/conf # The symlink is used to repair a deficiency in arch/um update-po-config: $(obj)/kxgettext $(obj)/gconf.glade.h $(Q)echo " GEN config" - $(Q)xgettext --default-domain=linux \ - --add-comments --keyword=_ --keyword=N_ \ - --from-code=UTF-8 \ - --files-from=scripts/kconfig/POTFILES.in \ + $(Q)xgettext --default-domain=linux \ + --add-comments --keyword=_ --keyword=N_ \ + --from-code=UTF-8 \ + --files-from=$(srctree)/scripts/kconfig/POTFILES.in \ + --directory=$(srctree) --directory=$(objtree) \ --output $(obj)/config.pot $(Q)sed -i s/CHARSET/UTF-8/ $(obj)/config.pot $(Q)ln -fs Kconfig.i386 arch/um/Kconfig.arch - $(Q)(for i in `ls arch/*/Kconfig`; \ + $(Q)(for i in `ls $(srctree)/arch/*/Kconfig`; \ do \ echo " GEN $$i"; \ $(obj)/kxgettext $$i \ @@ -92,7 +93,7 @@ update-po-config: $(obj)/kxgettext $(obj)/gconf.glade.h done ) $(Q)msguniq --sort-by-file --to-code=UTF-8 $(obj)/config.pot \ --output $(obj)/linux.pot - $(Q)rm -f arch/um/Kconfig.arch + $(Q)rm -f $(srctree)/arch/um/Kconfig.arch $(Q)rm -f $(obj)/config.pot PHONY += allnoconfig allyesconfig allmodconfig alldefconfig randconfig @@ -331,7 +332,8 @@ $(obj)/lkc_defs.h: $(src)/lkc_proto.h # Extract gconf menu items for I18N support $(obj)/gconf.glade.h: $(obj)/gconf.glade - intltool-extract --type=gettext/glade $(obj)/gconf.glade + intltool-extract --type=gettext/glade --srcdir=$(srctree) \ + $(obj)/gconf.glade ### # The following requires flex/bison/gperf -- cgit v1.2.3-71-gd317 From bdc69ca4cf972494ad06d1271760d94fdbb2e6b9 Mon Sep 17 00:00:00 2001 From: Peter Foley Date: Tue, 26 Apr 2011 18:13:56 -0400 Subject: kconfig: change update-po-config to reflect new layout of arch/um Signed-off-by: Peter Foley Signed-off-by: Michal Marek --- scripts/kconfig/Makefile | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'scripts') diff --git a/scripts/kconfig/Makefile b/scripts/kconfig/Makefile index 0f6483bccbe7..61cb06ce7b80 100644 --- a/scripts/kconfig/Makefile +++ b/scripts/kconfig/Makefile @@ -84,7 +84,7 @@ update-po-config: $(obj)/kxgettext $(obj)/gconf.glade.h --directory=$(srctree) --directory=$(objtree) \ --output $(obj)/config.pot $(Q)sed -i s/CHARSET/UTF-8/ $(obj)/config.pot - $(Q)ln -fs Kconfig.i386 arch/um/Kconfig.arch + $(Q)ln -fs Kconfig.x86 arch/um/Kconfig $(Q)(for i in `ls $(srctree)/arch/*/Kconfig`; \ do \ echo " GEN $$i"; \ @@ -93,7 +93,7 @@ update-po-config: $(obj)/kxgettext $(obj)/gconf.glade.h done ) $(Q)msguniq --sort-by-file --to-code=UTF-8 $(obj)/config.pot \ --output $(obj)/linux.pot - $(Q)rm -f $(srctree)/arch/um/Kconfig.arch + $(Q)rm -f $(srctree)/arch/um/Kconfig $(Q)rm -f $(obj)/config.pot PHONY += allnoconfig allyesconfig allmodconfig alldefconfig randconfig -- cgit v1.2.3-71-gd317 From 2d80eb0fa39bc4cfcc2e6d4eb1760a578fdeb507 Mon Sep 17 00:00:00 2001 From: Peter Foley Date: Tue, 26 Apr 2011 18:16:53 -0400 Subject: kconfig: quiet commands when V=0 Signed-off-by: Peter Foley Signed-off-by: Michal Marek --- scripts/kconfig/Makefile | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'scripts') diff --git a/scripts/kconfig/Makefile b/scripts/kconfig/Makefile index 61cb06ce7b80..faa9a4701b6f 100644 --- a/scripts/kconfig/Makefile +++ b/scripts/kconfig/Makefile @@ -328,11 +328,11 @@ $(obj)/%.moc: $(src)/%.h $(KC_QT_MOC) -i $< -o $@ $(obj)/lkc_defs.h: $(src)/lkc_proto.h - sed < $< > $@ 's/P(\([^,]*\),.*/#define \1 (\*\1_p)/' + $(Q)sed < $< > $@ 's/P(\([^,]*\),.*/#define \1 (\*\1_p)/' # Extract gconf menu items for I18N support $(obj)/gconf.glade.h: $(obj)/gconf.glade - intltool-extract --type=gettext/glade --srcdir=$(srctree) \ + $(Q)intltool-extract --type=gettext/glade --srcdir=$(srctree) \ $(obj)/gconf.glade ### -- cgit v1.2.3-71-gd317 From 6088e9ffa29a92e7b80fdba44929f3225c4c0357 Mon Sep 17 00:00:00 2001 From: Peter Foley Date: Tue, 26 Apr 2011 19:07:56 -0400 Subject: kbuild: don't warn about include/linux/version.h not including itself This patch makes checkversion.pl not warn that include/linux/version.h dosen't include itself. Signed-off-by: Peter Foley [mmarek: simplified to use 'next if' syntax] Signed-off-by: Michal Marek --- scripts/checkversion.pl | 1 + 1 file changed, 1 insertion(+) (limited to 'scripts') diff --git a/scripts/checkversion.pl b/scripts/checkversion.pl index b444e89a0095..5e490a8ceca5 100755 --- a/scripts/checkversion.pl +++ b/scripts/checkversion.pl @@ -12,6 +12,7 @@ $| = 1; my $debugging; foreach my $file (@ARGV) { + next if $file =~ "include/linux/version\.h"; # Open this file. open( my $f, '<', $file ) or die "Can't open $file: $!\n"; -- cgit v1.2.3-71-gd317 From f07726048d599acd6bac438e304645a78db753c0 Mon Sep 17 00:00:00 2001 From: Marcin Nowakowski Date: Mon, 25 Apr 2011 13:35:21 +0100 Subject: Fix handling of backlash character in LINUX_COMPILE_BY name When using a domain login, `whoami` returns the login in user\domain format. This leads to either warnings on unrecognised escape sequences or escaped characters being generated for the user. This patch ensures that any backslash is escaped to a double-backslash to make sure the name is preserved correctly. This patch does not enforce escaping on the KBUILD_BUILD_USER variable, as this is something the user has control of and can escape if required. Signed-off-by: Marcin Nowakowski Signed-off-by: Michal Marek --- scripts/mkcompile_h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'scripts') diff --git a/scripts/mkcompile_h b/scripts/mkcompile_h index 7ad6bf7a09ff..f221ddf69080 100755 --- a/scripts/mkcompile_h +++ b/scripts/mkcompile_h @@ -43,7 +43,7 @@ else TIMESTAMP=$KBUILD_BUILD_TIMESTAMP fi if test -z "$KBUILD_BUILD_USER"; then - LINUX_COMPILE_BY=`whoami` + LINUX_COMPILE_BY=$(whoami | sed 's/\\/\\\\/') else LINUX_COMPILE_BY=$KBUILD_BUILD_USER fi -- cgit v1.2.3-71-gd317 From af0e5d565d2fffcd97d1e2d89669d627cc04e8b8 Mon Sep 17 00:00:00 2001 From: Dave Jones Date: Thu, 21 Apr 2011 17:28:13 -0400 Subject: kbuild: Disable -Wunused-but-set-variable for gcc 4.6.0 Disable the new -Wunused-but-set-variable that was added in gcc 4.6.0 It produces more false positives than useful warnings. This can still be enabled using W=1 Signed-off-by: Dave Jones Acked-by: Sam Ravnborg Tested-by: Sam Ravnborg Signed-off-by: Michal Marek --- Makefile | 4 ++++ scripts/Makefile.build | 1 + 2 files changed, 5 insertions(+) (limited to 'scripts') diff --git a/Makefile b/Makefile index e509cc704968..4527dc23a724 100644 --- a/Makefile +++ b/Makefile @@ -567,6 +567,10 @@ ifndef CONFIG_CC_STACKPROTECTOR KBUILD_CFLAGS += $(call cc-option, -fno-stack-protector) endif +# This warning generated too much noise in a regular build. +# Use make W=1 to enable this warning (see scripts/Makefile.build) +KBUILD_CFLAGS += $(call cc-option, -Wno-unused-but-set-variable) + ifdef CONFIG_FRAME_POINTER KBUILD_CFLAGS += -fno-omit-frame-pointer -fno-optimize-sibling-calls else diff --git a/scripts/Makefile.build b/scripts/Makefile.build index 9c0c48127946..9fb19c0fbf8c 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -66,6 +66,7 @@ warning-1 += -Wmissing-format-attribute warning-1 += -Wmissing-prototypes warning-1 += -Wold-style-definition warning-1 += $(call cc-option, -Wmissing-include-dirs) +warning-1 += $(call cc-option, -Wunused-but-set-variable) warning-2 := -Waggregate-return warning-2 += -Wcast-align -- cgit v1.2.3-71-gd317 From a6de553da01c2c110c647fbd1c5bad29f5a82487 Mon Sep 17 00:00:00 2001 From: Michal Marek Date: Fri, 29 Apr 2011 14:45:31 +0200 Subject: kbuild: Allow to combine multiple W= levels Add support for make W=12, make W=123 and so on, to enable warnings from multiple W= levels. Normally, make W= does not include warnings from the previous level. Signed-off-by: Michal Marek Acked-by: Sam Ravnborg Reviewed-By: Valdis Kletnieks --- Makefile | 2 +- scripts/Makefile.build | 8 ++++++-- 2 files changed, 7 insertions(+), 3 deletions(-) (limited to 'scripts') diff --git a/Makefile b/Makefile index 4527dc23a724..d34250266f47 100644 --- a/Makefile +++ b/Makefile @@ -1290,7 +1290,7 @@ help: @echo ' 1: warnings which may be relevant and do not occur too often' @echo ' 2: warnings which occur quite often but may still be relevant' @echo ' 3: more obscure warnings, can most likely be ignored' - + @echo ' Multiple levels can be combined with W=12 or W=123' @echo '' @echo 'Execute "make" or "make all" to build all targets marked with [*] ' @echo 'For further info see the ./README file' diff --git a/scripts/Makefile.build b/scripts/Makefile.build index 9fb19c0fbf8c..f133641f815a 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -60,6 +60,8 @@ endif # $(call cc-option, -W...) handles gcc -W.. options which # are not supported by all versions of the compiler ifdef KBUILD_ENABLE_EXTRA_GCC_CHECKS +warning- := $(empty) + warning-1 := -Wextra -Wunused -Wno-unused-parameter warning-1 += -Wmissing-declarations warning-1 += -Wmissing-format-attribute @@ -86,9 +88,11 @@ warning-3 += -Wswitch-default warning-3 += $(call cc-option, -Wpacked-bitfield-compat) warning-3 += $(call cc-option, -Wvla) -warning := $(warning-$(KBUILD_ENABLE_EXTRA_GCC_CHECKS)) +warning := $(warning-$(findstring 1, $(KBUILD_ENABLE_EXTRA_GCC_CHECKS))) +warning += $(warning-$(findstring 2, $(KBUILD_ENABLE_EXTRA_GCC_CHECKS))) +warning += $(warning-$(findstring 3, $(KBUILD_ENABLE_EXTRA_GCC_CHECKS))) -ifeq ("$(warning)","") +ifeq ("$(strip $(warning))","") $(error W=$(KBUILD_ENABLE_EXTRA_GCC_CHECKS) is unknown) endif -- cgit v1.2.3-71-gd317 From 7a04fc94d9e45de50827ba6ff764f22990d55823 Mon Sep 17 00:00:00 2001 From: Michal Marek Date: Mon, 2 May 2011 18:01:06 +0200 Subject: kbuild: Fix Makefile.asm-generic for um Do nothing if arch/$(SRCARCH)/include/asm/Kbuild does not exist, which is the case of um. Reported-by: Randy Dunlap Signed-off-by: Michal Marek Acked-by: Randy Dunlap Acked-by: Sam Ravnborg --- scripts/Makefile.asm-generic | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'scripts') diff --git a/scripts/Makefile.asm-generic b/scripts/Makefile.asm-generic index a687cb697e35..490122c3e2aa 100644 --- a/scripts/Makefile.asm-generic +++ b/scripts/Makefile.asm-generic @@ -6,7 +6,7 @@ # a small wrapper file in $(obj) (arch/$(SRCARCH)/include/generated/asm) kbuild-file := $(srctree)/arch/$(SRCARCH)/include/asm/Kbuild -include $(kbuild-file) +-include $(kbuild-file) include scripts/Kbuild.include -- cgit v1.2.3-71-gd317 From bffd2020a972a188750e5cf4b9566950dfdf25a2 Mon Sep 17 00:00:00 2001 From: Peter Foley Date: Mon, 2 May 2011 22:48:03 +0200 Subject: kbuild: move scripts/basic/docproc.c to scripts/docproc.c Move docproc from scripts/basic to scripts so it is only built for *doc targets instead of every time the kernel is built. --- Documentation/DocBook/Makefile | 2 +- Makefile | 1 + scripts/.gitignore | 1 + scripts/Makefile | 7 +- scripts/basic/.gitignore | 2 - scripts/basic/Makefile | 3 +- scripts/basic/docproc.c | 583 ----------------------------------------- scripts/docproc.c | 583 +++++++++++++++++++++++++++++++++++++++++ 8 files changed, 592 insertions(+), 590 deletions(-) delete mode 100644 scripts/basic/docproc.c create mode 100644 scripts/docproc.c (limited to 'scripts') diff --git a/Documentation/DocBook/Makefile b/Documentation/DocBook/Makefile index 8436b018c289..3cebfa0d1611 100644 --- a/Documentation/DocBook/Makefile +++ b/Documentation/DocBook/Makefile @@ -73,7 +73,7 @@ installmandocs: mandocs ### #External programs used KERNELDOC = $(srctree)/scripts/kernel-doc -DOCPROC = $(objtree)/scripts/basic/docproc +DOCPROC = $(objtree)/scripts/docproc XMLTOFLAGS = -m $(srctree)/Documentation/DocBook/stylesheet.xsl XMLTOFLAGS += --skip-validation diff --git a/Makefile b/Makefile index d34250266f47..bc9eae424af8 100644 --- a/Makefile +++ b/Makefile @@ -1313,6 +1313,7 @@ $(help-board-dirs): help-%: # Documentation targets # --------------------------------------------------------------------------- %docs: scripts_basic FORCE + $(Q)$(MAKE) $(build)=scripts build_docproc $(Q)$(MAKE) $(build)=Documentation/DocBook $@ else # KBUILD_EXTMOD diff --git a/scripts/.gitignore b/scripts/.gitignore index e2741d23bab8..105b21f08185 100644 --- a/scripts/.gitignore +++ b/scripts/.gitignore @@ -8,3 +8,4 @@ bin2c unifdef ihex2fw recordmcount +docproc diff --git a/scripts/Makefile b/scripts/Makefile index fcea26168bca..df7678febf27 100644 --- a/scripts/Makefile +++ b/scripts/Makefile @@ -6,6 +6,7 @@ # pnmttologo: Convert pnm files to logo files # conmakehash: Create chartable # conmakehash: Create arrays for initializing the kernel console tables +# docproc: Used in Documentation/DocBook hostprogs-$(CONFIG_KALLSYMS) += kallsyms hostprogs-$(CONFIG_LOGO) += pnmtologo @@ -16,12 +17,14 @@ hostprogs-$(BUILD_C_RECORDMCOUNT) += recordmcount always := $(hostprogs-y) $(hostprogs-m) # The following hostprogs-y programs are only build on demand -hostprogs-y += unifdef +hostprogs-y += unifdef docproc -# This target is used internally to avoid "is up to date" messages +# These targets are used internally to avoid "is up to date" messages PHONY += build_unifdef build_unifdef: scripts/unifdef FORCE @: +build_docproc: scripts/docproc FORCE + @: subdir-$(CONFIG_MODVERSIONS) += genksyms subdir-y += mod diff --git a/scripts/basic/.gitignore b/scripts/basic/.gitignore index bf8b199ec598..a776371a3502 100644 --- a/scripts/basic/.gitignore +++ b/scripts/basic/.gitignore @@ -1,3 +1 @@ -hash fixdep -docproc diff --git a/scripts/basic/Makefile b/scripts/basic/Makefile index 4c324a1f1e0e..4fcef87bb875 100644 --- a/scripts/basic/Makefile +++ b/scripts/basic/Makefile @@ -7,9 +7,8 @@ # .config is included by main Makefile. # --------------------------------------------------------------------------- # fixdep: Used to generate dependency information during build process -# docproc: Used in Documentation/DocBook -hostprogs-y := fixdep docproc +hostprogs-y := fixdep always := $(hostprogs-y) # fixdep is needed to compile other host programs diff --git a/scripts/basic/docproc.c b/scripts/basic/docproc.c deleted file mode 100644 index 98dec87974d0..000000000000 --- a/scripts/basic/docproc.c +++ /dev/null @@ -1,583 +0,0 @@ -/* - * docproc is a simple preprocessor for the template files - * used as placeholders for the kernel internal documentation. - * docproc is used for documentation-frontend and - * dependency-generator. - * The two usages have in common that they require - * some knowledge of the .tmpl syntax, therefore they - * are kept together. - * - * documentation-frontend - * Scans the template file and call kernel-doc for - * all occurrences of ![EIF]file - * Beforehand each referenced file is scanned for - * any symbols that are exported via these macros: - * EXPORT_SYMBOL(), EXPORT_SYMBOL_GPL(), & - * EXPORT_SYMBOL_GPL_FUTURE() - * This is used to create proper -function and - * -nofunction arguments in calls to kernel-doc. - * Usage: docproc doc file.tmpl - * - * dependency-generator: - * Scans the template file and list all files - * referenced in a format recognized by make. - * Usage: docproc depend file.tmpl - * Writes dependency information to stdout - * in the following format: - * file.tmpl src.c src2.c - * The filenames are obtained from the following constructs: - * !Efilename - * !Ifilename - * !Dfilename - * !Ffilename - * !Pfilename - * - */ - -#define _GNU_SOURCE -#include -#include -#include -#include -#include -#include -#include -#include -#include - -/* exitstatus is used to keep track of any failing calls to kernel-doc, - * but execution continues. */ -int exitstatus = 0; - -typedef void DFL(char *); -DFL *defaultline; - -typedef void FILEONLY(char * file); -FILEONLY *internalfunctions; -FILEONLY *externalfunctions; -FILEONLY *symbolsonly; -FILEONLY *findall; - -typedef void FILELINE(char * file, char * line); -FILELINE * singlefunctions; -FILELINE * entity_system; -FILELINE * docsection; - -#define MAXLINESZ 2048 -#define MAXFILES 250 -#define KERNELDOCPATH "scripts/" -#define KERNELDOC "kernel-doc" -#define DOCBOOK "-docbook" -#define LIST "-list" -#define FUNCTION "-function" -#define NOFUNCTION "-nofunction" -#define NODOCSECTIONS "-no-doc-sections" - -static char *srctree, *kernsrctree; - -static char **all_list = NULL; -static int all_list_len = 0; - -static void consume_symbol(const char *sym) -{ - int i; - - for (i = 0; i < all_list_len; i++) { - if (!all_list[i]) - continue; - if (strcmp(sym, all_list[i])) - continue; - all_list[i] = NULL; - break; - } -} - -static void usage (void) -{ - fprintf(stderr, "Usage: docproc {doc|depend} file\n"); - fprintf(stderr, "Input is read from file.tmpl. Output is sent to stdout\n"); - fprintf(stderr, "doc: frontend when generating kernel documentation\n"); - fprintf(stderr, "depend: generate list of files referenced within file\n"); - fprintf(stderr, "Environment variable SRCTREE: absolute path to sources.\n"); - fprintf(stderr, " KBUILD_SRC: absolute path to kernel source tree.\n"); -} - -/* - * Execute kernel-doc with parameters given in svec - */ -static void exec_kernel_doc(char **svec) -{ - pid_t pid; - int ret; - char real_filename[PATH_MAX + 1]; - /* Make sure output generated so far are flushed */ - fflush(stdout); - switch (pid=fork()) { - case -1: - perror("fork"); - exit(1); - case 0: - memset(real_filename, 0, sizeof(real_filename)); - strncat(real_filename, kernsrctree, PATH_MAX); - strncat(real_filename, "/" KERNELDOCPATH KERNELDOC, - PATH_MAX - strlen(real_filename)); - execvp(real_filename, svec); - fprintf(stderr, "exec "); - perror(real_filename); - exit(1); - default: - waitpid(pid, &ret ,0); - } - if (WIFEXITED(ret)) - exitstatus |= WEXITSTATUS(ret); - else - exitstatus = 0xff; -} - -/* Types used to create list of all exported symbols in a number of files */ -struct symbols -{ - char *name; -}; - -struct symfile -{ - char *filename; - struct symbols *symbollist; - int symbolcnt; -}; - -struct symfile symfilelist[MAXFILES]; -int symfilecnt = 0; - -static void add_new_symbol(struct symfile *sym, char * symname) -{ - sym->symbollist = - realloc(sym->symbollist, (sym->symbolcnt + 1) * sizeof(char *)); - sym->symbollist[sym->symbolcnt++].name = strdup(symname); -} - -/* Add a filename to the list */ -static struct symfile * add_new_file(char * filename) -{ - symfilelist[symfilecnt++].filename = strdup(filename); - return &symfilelist[symfilecnt - 1]; -} - -/* Check if file already are present in the list */ -static struct symfile * filename_exist(char * filename) -{ - int i; - for (i=0; i < symfilecnt; i++) - if (strcmp(symfilelist[i].filename, filename) == 0) - return &symfilelist[i]; - return NULL; -} - -/* - * List all files referenced within the template file. - * Files are separated by tabs. - */ -static void adddep(char * file) { printf("\t%s", file); } -static void adddep2(char * file, char * line) { line = line; adddep(file); } -static void noaction(char * line) { line = line; } -static void noaction2(char * file, char * line) { file = file; line = line; } - -/* Echo the line without further action */ -static void printline(char * line) { printf("%s", line); } - -/* - * Find all symbols in filename that are exported with EXPORT_SYMBOL & - * EXPORT_SYMBOL_GPL (& EXPORT_SYMBOL_GPL_FUTURE implicitly). - * All symbols located are stored in symfilelist. - */ -static void find_export_symbols(char * filename) -{ - FILE * fp; - struct symfile *sym; - char line[MAXLINESZ]; - if (filename_exist(filename) == NULL) { - char real_filename[PATH_MAX + 1]; - memset(real_filename, 0, sizeof(real_filename)); - strncat(real_filename, srctree, PATH_MAX); - strncat(real_filename, "/", PATH_MAX - strlen(real_filename)); - strncat(real_filename, filename, - PATH_MAX - strlen(real_filename)); - sym = add_new_file(filename); - fp = fopen(real_filename, "r"); - if (fp == NULL) - { - fprintf(stderr, "docproc: "); - perror(real_filename); - exit(1); - } - while (fgets(line, MAXLINESZ, fp)) { - char *p; - char *e; - if (((p = strstr(line, "EXPORT_SYMBOL_GPL")) != NULL) || - ((p = strstr(line, "EXPORT_SYMBOL")) != NULL)) { - /* Skip EXPORT_SYMBOL{_GPL} */ - while (isalnum(*p) || *p == '_') - p++; - /* Remove parentheses & additional whitespace */ - while (isspace(*p)) - p++; - if (*p != '(') - continue; /* Syntax error? */ - else - p++; - while (isspace(*p)) - p++; - e = p; - while (isalnum(*e) || *e == '_') - e++; - *e = '\0'; - add_new_symbol(sym, p); - } - } - fclose(fp); - } -} - -/* - * Document all external or internal functions in a file. - * Call kernel-doc with following parameters: - * kernel-doc -docbook -nofunction function_name1 filename - * Function names are obtained from all the src files - * by find_export_symbols. - * intfunc uses -nofunction - * extfunc uses -function - */ -static void docfunctions(char * filename, char * type) -{ - int i,j; - int symcnt = 0; - int idx = 0; - char **vec; - - for (i=0; i <= symfilecnt; i++) - symcnt += symfilelist[i].symbolcnt; - vec = malloc((2 + 2 * symcnt + 3) * sizeof(char *)); - if (vec == NULL) { - perror("docproc: "); - exit(1); - } - vec[idx++] = KERNELDOC; - vec[idx++] = DOCBOOK; - vec[idx++] = NODOCSECTIONS; - for (i=0; i < symfilecnt; i++) { - struct symfile * sym = &symfilelist[i]; - for (j=0; j < sym->symbolcnt; j++) { - vec[idx++] = type; - consume_symbol(sym->symbollist[j].name); - vec[idx++] = sym->symbollist[j].name; - } - } - vec[idx++] = filename; - vec[idx] = NULL; - printf("\n", filename); - exec_kernel_doc(vec); - fflush(stdout); - free(vec); -} -static void intfunc(char * filename) { docfunctions(filename, NOFUNCTION); } -static void extfunc(char * filename) { docfunctions(filename, FUNCTION); } - -/* - * Document specific function(s) in a file. - * Call kernel-doc with the following parameters: - * kernel-doc -docbook -function function1 [-function function2] - */ -static void singfunc(char * filename, char * line) -{ - char *vec[200]; /* Enough for specific functions */ - int i, idx = 0; - int startofsym = 1; - vec[idx++] = KERNELDOC; - vec[idx++] = DOCBOOK; - - /* Split line up in individual parameters preceded by FUNCTION */ - for (i=0; line[i]; i++) { - if (isspace(line[i])) { - line[i] = '\0'; - startofsym = 1; - continue; - } - if (startofsym) { - startofsym = 0; - vec[idx++] = FUNCTION; - vec[idx++] = &line[i]; - } - } - for (i = 0; i < idx; i++) { - if (strcmp(vec[i], FUNCTION)) - continue; - consume_symbol(vec[i + 1]); - } - vec[idx++] = filename; - vec[idx] = NULL; - exec_kernel_doc(vec); -} - -/* - * Insert specific documentation section from a file. - * Call kernel-doc with the following parameters: - * kernel-doc -docbook -function "doc section" filename - */ -static void docsect(char *filename, char *line) -{ - char *vec[6]; /* kerneldoc -docbook -function "section" file NULL */ - char *s; - - for (s = line; *s; s++) - if (*s == '\n') - *s = '\0'; - - if (asprintf(&s, "DOC: %s", line) < 0) { - perror("asprintf"); - exit(1); - } - consume_symbol(s); - free(s); - - vec[0] = KERNELDOC; - vec[1] = DOCBOOK; - vec[2] = FUNCTION; - vec[3] = line; - vec[4] = filename; - vec[5] = NULL; - exec_kernel_doc(vec); -} - -static void find_all_symbols(char *filename) -{ - char *vec[4]; /* kerneldoc -list file NULL */ - pid_t pid; - int ret, i, count, start; - char real_filename[PATH_MAX + 1]; - int pipefd[2]; - char *data, *str; - size_t data_len = 0; - - vec[0] = KERNELDOC; - vec[1] = LIST; - vec[2] = filename; - vec[3] = NULL; - - if (pipe(pipefd)) { - perror("pipe"); - exit(1); - } - - switch (pid=fork()) { - case -1: - perror("fork"); - exit(1); - case 0: - close(pipefd[0]); - dup2(pipefd[1], 1); - memset(real_filename, 0, sizeof(real_filename)); - strncat(real_filename, kernsrctree, PATH_MAX); - strncat(real_filename, "/" KERNELDOCPATH KERNELDOC, - PATH_MAX - strlen(real_filename)); - execvp(real_filename, vec); - fprintf(stderr, "exec "); - perror(real_filename); - exit(1); - default: - close(pipefd[1]); - data = malloc(4096); - do { - while ((ret = read(pipefd[0], - data + data_len, - 4096)) > 0) { - data_len += ret; - data = realloc(data, data_len + 4096); - } - } while (ret == -EAGAIN); - if (ret != 0) { - perror("read"); - exit(1); - } - waitpid(pid, &ret ,0); - } - if (WIFEXITED(ret)) - exitstatus |= WEXITSTATUS(ret); - else - exitstatus = 0xff; - - count = 0; - /* poor man's strtok, but with counting */ - for (i = 0; i < data_len; i++) { - if (data[i] == '\n') { - count++; - data[i] = '\0'; - } - } - start = all_list_len; - all_list_len += count; - all_list = realloc(all_list, sizeof(char *) * all_list_len); - str = data; - for (i = 0; i < data_len && start != all_list_len; i++) { - if (data[i] == '\0') { - all_list[start] = str; - str = data + i + 1; - start++; - } - } -} - -/* - * Parse file, calling action specific functions for: - * 1) Lines containing !E - * 2) Lines containing !I - * 3) Lines containing !D - * 4) Lines containing !F - * 5) Lines containing !P - * 6) Lines containing !C - * 7) Default lines - lines not matching the above - */ -static void parse_file(FILE *infile) -{ - char line[MAXLINESZ]; - char * s; - while (fgets(line, MAXLINESZ, infile)) { - if (line[0] == '!') { - s = line + 2; - switch (line[1]) { - case 'E': - while (*s && !isspace(*s)) s++; - *s = '\0'; - externalfunctions(line+2); - break; - case 'I': - while (*s && !isspace(*s)) s++; - *s = '\0'; - internalfunctions(line+2); - break; - case 'D': - while (*s && !isspace(*s)) s++; - *s = '\0'; - symbolsonly(line+2); - break; - case 'F': - /* filename */ - while (*s && !isspace(*s)) s++; - *s++ = '\0'; - /* function names */ - while (isspace(*s)) - s++; - singlefunctions(line +2, s); - break; - case 'P': - /* filename */ - while (*s && !isspace(*s)) s++; - *s++ = '\0'; - /* DOC: section name */ - while (isspace(*s)) - s++; - docsection(line + 2, s); - break; - case 'C': - while (*s && !isspace(*s)) s++; - *s = '\0'; - if (findall) - findall(line+2); - break; - default: - defaultline(line); - } - } - else { - defaultline(line); - } - } - fflush(stdout); -} - - -int main(int argc, char *argv[]) -{ - FILE * infile; - int i; - - srctree = getenv("SRCTREE"); - if (!srctree) - srctree = getcwd(NULL, 0); - kernsrctree = getenv("KBUILD_SRC"); - if (!kernsrctree || !*kernsrctree) - kernsrctree = srctree; - if (argc != 3) { - usage(); - exit(1); - } - /* Open file, exit on error */ - infile = fopen(argv[2], "r"); - if (infile == NULL) { - fprintf(stderr, "docproc: "); - perror(argv[2]); - exit(2); - } - - if (strcmp("doc", argv[1]) == 0) - { - /* Need to do this in two passes. - * First pass is used to collect all symbols exported - * in the various files; - * Second pass generate the documentation. - * This is required because some functions are declared - * and exported in different files :-(( - */ - /* Collect symbols */ - defaultline = noaction; - internalfunctions = find_export_symbols; - externalfunctions = find_export_symbols; - symbolsonly = find_export_symbols; - singlefunctions = noaction2; - docsection = noaction2; - findall = find_all_symbols; - parse_file(infile); - - /* Rewind to start from beginning of file again */ - fseek(infile, 0, SEEK_SET); - defaultline = printline; - internalfunctions = intfunc; - externalfunctions = extfunc; - symbolsonly = printline; - singlefunctions = singfunc; - docsection = docsect; - findall = NULL; - - parse_file(infile); - - for (i = 0; i < all_list_len; i++) { - if (!all_list[i]) - continue; - fprintf(stderr, "Warning: didn't use docs for %s\n", - all_list[i]); - } - } - else if (strcmp("depend", argv[1]) == 0) - { - /* Create first part of dependency chain - * file.tmpl */ - printf("%s\t", argv[2]); - defaultline = noaction; - internalfunctions = adddep; - externalfunctions = adddep; - symbolsonly = adddep; - singlefunctions = adddep2; - docsection = adddep2; - findall = adddep; - parse_file(infile); - printf("\n"); - } - else - { - fprintf(stderr, "Unknown option: %s\n", argv[1]); - exit(1); - } - fclose(infile); - fflush(stdout); - return exitstatus; -} diff --git a/scripts/docproc.c b/scripts/docproc.c new file mode 100644 index 000000000000..98dec87974d0 --- /dev/null +++ b/scripts/docproc.c @@ -0,0 +1,583 @@ +/* + * docproc is a simple preprocessor for the template files + * used as placeholders for the kernel internal documentation. + * docproc is used for documentation-frontend and + * dependency-generator. + * The two usages have in common that they require + * some knowledge of the .tmpl syntax, therefore they + * are kept together. + * + * documentation-frontend + * Scans the template file and call kernel-doc for + * all occurrences of ![EIF]file + * Beforehand each referenced file is scanned for + * any symbols that are exported via these macros: + * EXPORT_SYMBOL(), EXPORT_SYMBOL_GPL(), & + * EXPORT_SYMBOL_GPL_FUTURE() + * This is used to create proper -function and + * -nofunction arguments in calls to kernel-doc. + * Usage: docproc doc file.tmpl + * + * dependency-generator: + * Scans the template file and list all files + * referenced in a format recognized by make. + * Usage: docproc depend file.tmpl + * Writes dependency information to stdout + * in the following format: + * file.tmpl src.c src2.c + * The filenames are obtained from the following constructs: + * !Efilename + * !Ifilename + * !Dfilename + * !Ffilename + * !Pfilename + * + */ + +#define _GNU_SOURCE +#include +#include +#include +#include +#include +#include +#include +#include +#include + +/* exitstatus is used to keep track of any failing calls to kernel-doc, + * but execution continues. */ +int exitstatus = 0; + +typedef void DFL(char *); +DFL *defaultline; + +typedef void FILEONLY(char * file); +FILEONLY *internalfunctions; +FILEONLY *externalfunctions; +FILEONLY *symbolsonly; +FILEONLY *findall; + +typedef void FILELINE(char * file, char * line); +FILELINE * singlefunctions; +FILELINE * entity_system; +FILELINE * docsection; + +#define MAXLINESZ 2048 +#define MAXFILES 250 +#define KERNELDOCPATH "scripts/" +#define KERNELDOC "kernel-doc" +#define DOCBOOK "-docbook" +#define LIST "-list" +#define FUNCTION "-function" +#define NOFUNCTION "-nofunction" +#define NODOCSECTIONS "-no-doc-sections" + +static char *srctree, *kernsrctree; + +static char **all_list = NULL; +static int all_list_len = 0; + +static void consume_symbol(const char *sym) +{ + int i; + + for (i = 0; i < all_list_len; i++) { + if (!all_list[i]) + continue; + if (strcmp(sym, all_list[i])) + continue; + all_list[i] = NULL; + break; + } +} + +static void usage (void) +{ + fprintf(stderr, "Usage: docproc {doc|depend} file\n"); + fprintf(stderr, "Input is read from file.tmpl. Output is sent to stdout\n"); + fprintf(stderr, "doc: frontend when generating kernel documentation\n"); + fprintf(stderr, "depend: generate list of files referenced within file\n"); + fprintf(stderr, "Environment variable SRCTREE: absolute path to sources.\n"); + fprintf(stderr, " KBUILD_SRC: absolute path to kernel source tree.\n"); +} + +/* + * Execute kernel-doc with parameters given in svec + */ +static void exec_kernel_doc(char **svec) +{ + pid_t pid; + int ret; + char real_filename[PATH_MAX + 1]; + /* Make sure output generated so far are flushed */ + fflush(stdout); + switch (pid=fork()) { + case -1: + perror("fork"); + exit(1); + case 0: + memset(real_filename, 0, sizeof(real_filename)); + strncat(real_filename, kernsrctree, PATH_MAX); + strncat(real_filename, "/" KERNELDOCPATH KERNELDOC, + PATH_MAX - strlen(real_filename)); + execvp(real_filename, svec); + fprintf(stderr, "exec "); + perror(real_filename); + exit(1); + default: + waitpid(pid, &ret ,0); + } + if (WIFEXITED(ret)) + exitstatus |= WEXITSTATUS(ret); + else + exitstatus = 0xff; +} + +/* Types used to create list of all exported symbols in a number of files */ +struct symbols +{ + char *name; +}; + +struct symfile +{ + char *filename; + struct symbols *symbollist; + int symbolcnt; +}; + +struct symfile symfilelist[MAXFILES]; +int symfilecnt = 0; + +static void add_new_symbol(struct symfile *sym, char * symname) +{ + sym->symbollist = + realloc(sym->symbollist, (sym->symbolcnt + 1) * sizeof(char *)); + sym->symbollist[sym->symbolcnt++].name = strdup(symname); +} + +/* Add a filename to the list */ +static struct symfile * add_new_file(char * filename) +{ + symfilelist[symfilecnt++].filename = strdup(filename); + return &symfilelist[symfilecnt - 1]; +} + +/* Check if file already are present in the list */ +static struct symfile * filename_exist(char * filename) +{ + int i; + for (i=0; i < symfilecnt; i++) + if (strcmp(symfilelist[i].filename, filename) == 0) + return &symfilelist[i]; + return NULL; +} + +/* + * List all files referenced within the template file. + * Files are separated by tabs. + */ +static void adddep(char * file) { printf("\t%s", file); } +static void adddep2(char * file, char * line) { line = line; adddep(file); } +static void noaction(char * line) { line = line; } +static void noaction2(char * file, char * line) { file = file; line = line; } + +/* Echo the line without further action */ +static void printline(char * line) { printf("%s", line); } + +/* + * Find all symbols in filename that are exported with EXPORT_SYMBOL & + * EXPORT_SYMBOL_GPL (& EXPORT_SYMBOL_GPL_FUTURE implicitly). + * All symbols located are stored in symfilelist. + */ +static void find_export_symbols(char * filename) +{ + FILE * fp; + struct symfile *sym; + char line[MAXLINESZ]; + if (filename_exist(filename) == NULL) { + char real_filename[PATH_MAX + 1]; + memset(real_filename, 0, sizeof(real_filename)); + strncat(real_filename, srctree, PATH_MAX); + strncat(real_filename, "/", PATH_MAX - strlen(real_filename)); + strncat(real_filename, filename, + PATH_MAX - strlen(real_filename)); + sym = add_new_file(filename); + fp = fopen(real_filename, "r"); + if (fp == NULL) + { + fprintf(stderr, "docproc: "); + perror(real_filename); + exit(1); + } + while (fgets(line, MAXLINESZ, fp)) { + char *p; + char *e; + if (((p = strstr(line, "EXPORT_SYMBOL_GPL")) != NULL) || + ((p = strstr(line, "EXPORT_SYMBOL")) != NULL)) { + /* Skip EXPORT_SYMBOL{_GPL} */ + while (isalnum(*p) || *p == '_') + p++; + /* Remove parentheses & additional whitespace */ + while (isspace(*p)) + p++; + if (*p != '(') + continue; /* Syntax error? */ + else + p++; + while (isspace(*p)) + p++; + e = p; + while (isalnum(*e) || *e == '_') + e++; + *e = '\0'; + add_new_symbol(sym, p); + } + } + fclose(fp); + } +} + +/* + * Document all external or internal functions in a file. + * Call kernel-doc with following parameters: + * kernel-doc -docbook -nofunction function_name1 filename + * Function names are obtained from all the src files + * by find_export_symbols. + * intfunc uses -nofunction + * extfunc uses -function + */ +static void docfunctions(char * filename, char * type) +{ + int i,j; + int symcnt = 0; + int idx = 0; + char **vec; + + for (i=0; i <= symfilecnt; i++) + symcnt += symfilelist[i].symbolcnt; + vec = malloc((2 + 2 * symcnt + 3) * sizeof(char *)); + if (vec == NULL) { + perror("docproc: "); + exit(1); + } + vec[idx++] = KERNELDOC; + vec[idx++] = DOCBOOK; + vec[idx++] = NODOCSECTIONS; + for (i=0; i < symfilecnt; i++) { + struct symfile * sym = &symfilelist[i]; + for (j=0; j < sym->symbolcnt; j++) { + vec[idx++] = type; + consume_symbol(sym->symbollist[j].name); + vec[idx++] = sym->symbollist[j].name; + } + } + vec[idx++] = filename; + vec[idx] = NULL; + printf("\n", filename); + exec_kernel_doc(vec); + fflush(stdout); + free(vec); +} +static void intfunc(char * filename) { docfunctions(filename, NOFUNCTION); } +static void extfunc(char * filename) { docfunctions(filename, FUNCTION); } + +/* + * Document specific function(s) in a file. + * Call kernel-doc with the following parameters: + * kernel-doc -docbook -function function1 [-function function2] + */ +static void singfunc(char * filename, char * line) +{ + char *vec[200]; /* Enough for specific functions */ + int i, idx = 0; + int startofsym = 1; + vec[idx++] = KERNELDOC; + vec[idx++] = DOCBOOK; + + /* Split line up in individual parameters preceded by FUNCTION */ + for (i=0; line[i]; i++) { + if (isspace(line[i])) { + line[i] = '\0'; + startofsym = 1; + continue; + } + if (startofsym) { + startofsym = 0; + vec[idx++] = FUNCTION; + vec[idx++] = &line[i]; + } + } + for (i = 0; i < idx; i++) { + if (strcmp(vec[i], FUNCTION)) + continue; + consume_symbol(vec[i + 1]); + } + vec[idx++] = filename; + vec[idx] = NULL; + exec_kernel_doc(vec); +} + +/* + * Insert specific documentation section from a file. + * Call kernel-doc with the following parameters: + * kernel-doc -docbook -function "doc section" filename + */ +static void docsect(char *filename, char *line) +{ + char *vec[6]; /* kerneldoc -docbook -function "section" file NULL */ + char *s; + + for (s = line; *s; s++) + if (*s == '\n') + *s = '\0'; + + if (asprintf(&s, "DOC: %s", line) < 0) { + perror("asprintf"); + exit(1); + } + consume_symbol(s); + free(s); + + vec[0] = KERNELDOC; + vec[1] = DOCBOOK; + vec[2] = FUNCTION; + vec[3] = line; + vec[4] = filename; + vec[5] = NULL; + exec_kernel_doc(vec); +} + +static void find_all_symbols(char *filename) +{ + char *vec[4]; /* kerneldoc -list file NULL */ + pid_t pid; + int ret, i, count, start; + char real_filename[PATH_MAX + 1]; + int pipefd[2]; + char *data, *str; + size_t data_len = 0; + + vec[0] = KERNELDOC; + vec[1] = LIST; + vec[2] = filename; + vec[3] = NULL; + + if (pipe(pipefd)) { + perror("pipe"); + exit(1); + } + + switch (pid=fork()) { + case -1: + perror("fork"); + exit(1); + case 0: + close(pipefd[0]); + dup2(pipefd[1], 1); + memset(real_filename, 0, sizeof(real_filename)); + strncat(real_filename, kernsrctree, PATH_MAX); + strncat(real_filename, "/" KERNELDOCPATH KERNELDOC, + PATH_MAX - strlen(real_filename)); + execvp(real_filename, vec); + fprintf(stderr, "exec "); + perror(real_filename); + exit(1); + default: + close(pipefd[1]); + data = malloc(4096); + do { + while ((ret = read(pipefd[0], + data + data_len, + 4096)) > 0) { + data_len += ret; + data = realloc(data, data_len + 4096); + } + } while (ret == -EAGAIN); + if (ret != 0) { + perror("read"); + exit(1); + } + waitpid(pid, &ret ,0); + } + if (WIFEXITED(ret)) + exitstatus |= WEXITSTATUS(ret); + else + exitstatus = 0xff; + + count = 0; + /* poor man's strtok, but with counting */ + for (i = 0; i < data_len; i++) { + if (data[i] == '\n') { + count++; + data[i] = '\0'; + } + } + start = all_list_len; + all_list_len += count; + all_list = realloc(all_list, sizeof(char *) * all_list_len); + str = data; + for (i = 0; i < data_len && start != all_list_len; i++) { + if (data[i] == '\0') { + all_list[start] = str; + str = data + i + 1; + start++; + } + } +} + +/* + * Parse file, calling action specific functions for: + * 1) Lines containing !E + * 2) Lines containing !I + * 3) Lines containing !D + * 4) Lines containing !F + * 5) Lines containing !P + * 6) Lines containing !C + * 7) Default lines - lines not matching the above + */ +static void parse_file(FILE *infile) +{ + char line[MAXLINESZ]; + char * s; + while (fgets(line, MAXLINESZ, infile)) { + if (line[0] == '!') { + s = line + 2; + switch (line[1]) { + case 'E': + while (*s && !isspace(*s)) s++; + *s = '\0'; + externalfunctions(line+2); + break; + case 'I': + while (*s && !isspace(*s)) s++; + *s = '\0'; + internalfunctions(line+2); + break; + case 'D': + while (*s && !isspace(*s)) s++; + *s = '\0'; + symbolsonly(line+2); + break; + case 'F': + /* filename */ + while (*s && !isspace(*s)) s++; + *s++ = '\0'; + /* function names */ + while (isspace(*s)) + s++; + singlefunctions(line +2, s); + break; + case 'P': + /* filename */ + while (*s && !isspace(*s)) s++; + *s++ = '\0'; + /* DOC: section name */ + while (isspace(*s)) + s++; + docsection(line + 2, s); + break; + case 'C': + while (*s && !isspace(*s)) s++; + *s = '\0'; + if (findall) + findall(line+2); + break; + default: + defaultline(line); + } + } + else { + defaultline(line); + } + } + fflush(stdout); +} + + +int main(int argc, char *argv[]) +{ + FILE * infile; + int i; + + srctree = getenv("SRCTREE"); + if (!srctree) + srctree = getcwd(NULL, 0); + kernsrctree = getenv("KBUILD_SRC"); + if (!kernsrctree || !*kernsrctree) + kernsrctree = srctree; + if (argc != 3) { + usage(); + exit(1); + } + /* Open file, exit on error */ + infile = fopen(argv[2], "r"); + if (infile == NULL) { + fprintf(stderr, "docproc: "); + perror(argv[2]); + exit(2); + } + + if (strcmp("doc", argv[1]) == 0) + { + /* Need to do this in two passes. + * First pass is used to collect all symbols exported + * in the various files; + * Second pass generate the documentation. + * This is required because some functions are declared + * and exported in different files :-(( + */ + /* Collect symbols */ + defaultline = noaction; + internalfunctions = find_export_symbols; + externalfunctions = find_export_symbols; + symbolsonly = find_export_symbols; + singlefunctions = noaction2; + docsection = noaction2; + findall = find_all_symbols; + parse_file(infile); + + /* Rewind to start from beginning of file again */ + fseek(infile, 0, SEEK_SET); + defaultline = printline; + internalfunctions = intfunc; + externalfunctions = extfunc; + symbolsonly = printline; + singlefunctions = singfunc; + docsection = docsect; + findall = NULL; + + parse_file(infile); + + for (i = 0; i < all_list_len; i++) { + if (!all_list[i]) + continue; + fprintf(stderr, "Warning: didn't use docs for %s\n", + all_list[i]); + } + } + else if (strcmp("depend", argv[1]) == 0) + { + /* Create first part of dependency chain + * file.tmpl */ + printf("%s\t", argv[2]); + defaultline = noaction; + internalfunctions = adddep; + externalfunctions = adddep; + symbolsonly = adddep; + singlefunctions = adddep2; + docsection = adddep2; + findall = adddep; + parse_file(infile); + printf("\n"); + } + else + { + fprintf(stderr, "Unknown option: %s\n", argv[1]); + exit(1); + } + fclose(infile); + fflush(stdout); + return exitstatus; +} -- cgit v1.2.3-71-gd317 From 8417da6f2128008c431c7d130af6cd3d9079922e Mon Sep 17 00:00:00 2001 From: Michal Marek Date: Mon, 2 May 2011 12:51:15 +0200 Subject: kbuild: Fix passing -Wno-* options to gcc 4.4+ Starting with 4.4, gcc will happily accept -Wno- in the cc-option test and complain later when compiling a file that has some other warning. This rather unexpected behavior is intentional as per http://gcc.gnu.org/PR28322, so work around it by testing for support of the opposite option (without the no-). Introduce a new Makefile function cc-disable-warning that does this and update two uses of cc-option in the toplevel Makefile. Reported-and-tested-by: Stephen Rothwell Signed-off-by: Michal Marek --- Documentation/kbuild/makefiles.txt | 12 ++++++++++++ Makefile | 4 ++-- scripts/Kbuild.include | 5 +++++ 3 files changed, 19 insertions(+), 2 deletions(-) (limited to 'scripts') diff --git a/Documentation/kbuild/makefiles.txt b/Documentation/kbuild/makefiles.txt index 835b64acf0b4..47435e56c5da 100644 --- a/Documentation/kbuild/makefiles.txt +++ b/Documentation/kbuild/makefiles.txt @@ -501,6 +501,18 @@ more details, with real examples. gcc >= 3.00. For gcc < 3.00, -malign-functions=4 is used. Note: cc-option-align uses KBUILD_CFLAGS for $(CC) options + cc-disable-warning + cc-disable-warning checks if gcc supports a given warning and returns + the commandline switch to disable it. This special function is needed, + because gcc 4.4 and later accept any unknown -Wno-* option and only + warn about it if there is another warning in the source file. + + Example: + KBUILD_CFLAGS += $(call cc-disable-warning, unused-but-set-variable) + + In the above example, -Wno-unused-but-set-variable will be added to + KBUILD_CFLAGS only if gcc really accepts it. + cc-version cc-version returns a numerical version of the $(CC) compiler version. The format is where both are two digits. So for example diff --git a/Makefile b/Makefile index bc9eae424af8..5cf4eb03fb3e 100644 --- a/Makefile +++ b/Makefile @@ -569,7 +569,7 @@ endif # This warning generated too much noise in a regular build. # Use make W=1 to enable this warning (see scripts/Makefile.build) -KBUILD_CFLAGS += $(call cc-option, -Wno-unused-but-set-variable) +KBUILD_CFLAGS += $(call cc-disable-warning, unused-but-set-variable) ifdef CONFIG_FRAME_POINTER KBUILD_CFLAGS += -fno-omit-frame-pointer -fno-optimize-sibling-calls @@ -616,7 +616,7 @@ CHECKFLAGS += $(NOSTDINC_FLAGS) KBUILD_CFLAGS += $(call cc-option,-Wdeclaration-after-statement,) # disable pointer signed / unsigned warnings in gcc 4.0 -KBUILD_CFLAGS += $(call cc-option,-Wno-pointer-sign,) +KBUILD_CFLAGS += $(call cc-disable-warning, pointer-sign) # disable invalid "can't wrap" optimizations for signed / pointers KBUILD_CFLAGS += $(call cc-option,-fno-strict-overflow) diff --git a/scripts/Kbuild.include b/scripts/Kbuild.include index fae2d8d8cb09..c034dd7161a6 100644 --- a/scripts/Kbuild.include +++ b/scripts/Kbuild.include @@ -118,6 +118,11 @@ cc-option-yn = $(call try-run,\ cc-option-align = $(subst -functions=0,,\ $(call cc-option,-falign-functions=0,-malign-functions=0)) +# cc-disable-warning +# Usage: cflags-y += $(call cc-disable-warning,unused-but-set-variable) +cc-disable-warning = $(call try-run,\ + $(CC) $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) -W$(strip $(1)) -c -xc /dev/null -o "$$TMP",-Wno-$(strip $(1))) + # cc-version # Usage gcc-ver := $(call cc-version) cc-version = $(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-version.sh $(CC)) -- cgit v1.2.3-71-gd317 From e1287eb891e326ea8451b03ba1f9b0d66abdb13d Mon Sep 17 00:00:00 2001 From: Arun Sharma Date: Wed, 4 May 2011 13:48:11 -0700 Subject: Replace '-' in kernel version with '_' Removing the '-' results in hard to read filenames such as: kernel-2.6.35.2000042g76e4caf-28.x86_64.rpm kernel-2.6.35.2_000042_g76e4caf-28.x86_64.rpm is easier to read. Signed-off-by: Arun Sharma Signed-off-by: Michal Marek --- scripts/package/Makefile | 2 +- scripts/package/mkspec | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) (limited to 'scripts') diff --git a/scripts/package/Makefile b/scripts/package/Makefile index a834b935f536..1b7eaea83123 100644 --- a/scripts/package/Makefile +++ b/scripts/package/Makefile @@ -26,7 +26,7 @@ RPM := $(shell if [ -x "/usr/bin/rpmbuild" ]; then echo rpmbuild; \ else echo rpm; fi) # Remove hyphens since they have special meaning in RPM filenames -KERNELPATH := kernel-$(subst -,,$(KERNELRELEASE)) +KERNELPATH := kernel-$(subst -,_,$(KERNELRELEASE)) MKSPEC := $(srctree)/scripts/package/mkspec PREV := set -e; cd ..; diff --git a/scripts/package/mkspec b/scripts/package/mkspec index e1c1d5b8ca70..ed8b6a8b4b8e 100755 --- a/scripts/package/mkspec +++ b/scripts/package/mkspec @@ -22,7 +22,7 @@ if [ "`grep CONFIG_DRM=y .config | cut -f2 -d\=`" = "y" ]; then fi PROVIDES="$PROVIDES kernel-$KERNELRELEASE" -__KERNELRELEASE=`echo $KERNELRELEASE | sed -e "s/-//g"` +__KERNELRELEASE=`echo $KERNELRELEASE | sed -e "s/-/_/g"` echo "Name: kernel" echo "Summary: The Linux Kernel" -- cgit v1.2.3-71-gd317 From 153f01147065cb3628493dcb79417bc4474320c7 Mon Sep 17 00:00:00 2001 From: Jamey Sharp Date: Thu, 5 May 2011 12:03:47 -0700 Subject: scripts/gen_initramfs_list.sh: Convert to a /bin/sh script Replace bashisms with POSIX-compatible shell scripting. Notably, de-duplicate '/' using a sed command from elsewhere in the same script rather than "${name//\/\///}". Commit by Jamey Sharp and Josh Triplett. Signed-off-by: Jamey Sharp Signed-off-by: Josh Triplett Cc: Andrew Morton Signed-off-by: Michal Marek --- scripts/gen_initramfs_list.sh | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) (limited to 'scripts') diff --git a/scripts/gen_initramfs_list.sh b/scripts/gen_initramfs_list.sh index d44cf675bc22..8da7890310d6 100644 --- a/scripts/gen_initramfs_list.sh +++ b/scripts/gen_initramfs_list.sh @@ -1,4 +1,4 @@ -#!/bin/bash +#!/bin/sh # Copyright (C) Martin Schlemmer # Copyright (C) 2006 Sam Ravnborg # @@ -105,9 +105,9 @@ list_parse() { # for links, devices etc the format differs. See gen_init_cpio for details parse() { local location="$1" - local name="${location/${srcdir}//}" + local name="/${location#${srcdir}}" # change '//' into '/' - name="${name//\/\///}" + name=$(echo "$name" | sed -e 's://*:/:g') local mode="$2" local uid="$3" local gid="$4" @@ -117,8 +117,8 @@ parse() { [ "$root_gid" = "squash" ] && gid=0 || [ "$gid" -eq "$root_gid" ] && gid=0 local str="${mode} ${uid} ${gid}" - [ "${ftype}" == "invalid" ] && return 0 - [ "${location}" == "${srcdir}" ] && return 0 + [ "${ftype}" = "invalid" ] && return 0 + [ "${location}" = "${srcdir}" ] && return 0 case "${ftype}" in "file") @@ -192,7 +192,7 @@ input_file() { if [ -f "$1" ]; then ${dep_list}header "$1" is_cpio="$(echo "$1" | sed 's/^.*\.cpio\(\..*\)\?/cpio/')" - if [ $2 -eq 0 -a ${is_cpio} == "cpio" ]; then + if [ $2 -eq 0 -a ${is_cpio} = "cpio" ]; then cpio_file=$1 echo "$1" | grep -q '^.*\.cpio\..*' && is_cpio_compressed="compressed" [ ! -z ${dep_list} ] && echo "$1" @@ -204,7 +204,7 @@ input_file() { else echo "$1 \\" cat "$1" | while read type dir file perm ; do - if [ "$type" == "file" ]; then + if [ "$type" = "file" ]; then echo "$file \\"; fi done -- cgit v1.2.3-71-gd317 From e0a04b11e4059cab033469617c2a3ce2d8cab416 Mon Sep 17 00:00:00 2001 From: Xiaochen Wang Date: Sun, 1 May 2011 11:41:41 +0800 Subject: scripts/kallsyms.c: fix potential segfault Description: This bug hardly appears during real kernel compiling, because the vmlinux symbols table is huge. But we can still catch it under strict condition , as follows. $ echo "c101b97b T do_fork" | ./scripts/kallsyms --all-symbols #include ...... ...... .globl kallsyms_token_table ALGN kallsyms_token_table: Segmentation fault (core dumped) $ If symbols table is small, all entries in token_profit[0x10000] may decrease to 0 after several calls of compress_symbols() in optimize_result(). In that case, find_best_token() always return 0 and best_table[i] is set to "\0\0" and best_table_len[i] is set to 2. As a result, expand_symbol(best_table[0]="\0\0", best_table_len[0]=2, buf) in write_src() will run in infinite recursion until stack overflows, causing segfault. This patch checks the find_best_token() return value. If all entries in token_profit[0x10000] become 0 according to return value, it breaks the loop in optimize_result(). And expand_symbol() works well when best_table_len[i] is 0. Signed-off-by: Xiaochen Wang Acked-by: Paulo Marques Signed-off-by: Michal Marek --- scripts/kallsyms.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'scripts') diff --git a/scripts/kallsyms.c b/scripts/kallsyms.c index 60dd3eb9366e..487ac6f37ca2 100644 --- a/scripts/kallsyms.c +++ b/scripts/kallsyms.c @@ -500,6 +500,8 @@ static void optimize_result(void) /* find the token with the breates profit value */ best = find_best_token(); + if (token_profit[best] == 0) + break; /* place it in the "best" table */ best_table_len[i] = 2; -- cgit v1.2.3-71-gd317 From c4d5ee13984f57b2f881635c49045151679f5e8a Mon Sep 17 00:00:00 2001 From: Michal Marek Date: Mon, 16 May 2011 16:37:34 +0200 Subject: kbuild: make KBUILD_NOCMDDEP=1 handle empty built-in.o Based on a patch by Rabin Vincent. Fix building with KBUILD_NOCMDDEP=1, which currently does not work because it does not build built-in.o with no dependencies: LD fs/notify/built-in.o ld: cannot find fs/notify/dnotify/built-in.o: No such file or directory ld: cannot find fs/notify/inotify/built-in.o: No such file or directory ld: cannot find fs/notify/fanotify/built-in.o: No such file or directory Reported-and-tested-by: Rabin Vincent Signed-off-by: Michal Marek --- scripts/Kbuild.include | 2 ++ 1 file changed, 2 insertions(+) (limited to 'scripts') diff --git a/scripts/Kbuild.include b/scripts/Kbuild.include index c034dd7161a6..be39cd1c74cf 100644 --- a/scripts/Kbuild.include +++ b/scripts/Kbuild.include @@ -197,6 +197,8 @@ ifneq ($(KBUILD_NOCMDDEP),1) # User may override this check using make KBUILD_NOCMDDEP=1 arg-check = $(strip $(filter-out $(cmd_$(1)), $(cmd_$@)) \ $(filter-out $(cmd_$@), $(cmd_$(1))) ) +else +arg-check = $(if $(strip $(cmd_$@)),,1) endif # >'< substitution is for echo to work, -- cgit v1.2.3-71-gd317 From d410fa4ef99112386de5f218dd7df7b4fca910b4 Mon Sep 17 00:00:00 2001 From: Randy Dunlap Date: Thu, 19 May 2011 15:59:38 -0700 Subject: Create Documentation/security/, move LSM-, credentials-, and keys-related files from Documentation/ to Documentation/security/, add Documentation/security/00-INDEX, and update all occurrences of Documentation/ to Documentation/security/. --- Documentation/00-INDEX | 6 +- Documentation/SELinux.txt | 27 - Documentation/Smack.txt | 541 --------- Documentation/apparmor.txt | 39 - Documentation/credentials.txt | 581 ---------- Documentation/filesystems/nfs/idmapper.txt | 4 +- Documentation/keys-request-key.txt | 202 ---- Documentation/keys-trusted-encrypted.txt | 145 --- Documentation/keys.txt | 1290 --------------------- Documentation/networking/dns_resolver.txt | 4 +- Documentation/security/00-INDEX | 18 + Documentation/security/SELinux.txt | 27 + Documentation/security/Smack.txt | 541 +++++++++ Documentation/security/apparmor.txt | 39 + Documentation/security/credentials.txt | 581 ++++++++++ Documentation/security/keys-request-key.txt | 202 ++++ Documentation/security/keys-trusted-encrypted.txt | 145 +++ Documentation/security/keys.txt | 1290 +++++++++++++++++++++ Documentation/security/tomoyo.txt | 55 + Documentation/tomoyo.txt | 55 - MAINTAINERS | 6 +- include/linux/cred.h | 2 +- include/linux/key.h | 2 +- kernel/cred.c | 2 +- scripts/selinux/README | 2 +- security/apparmor/match.c | 2 +- security/apparmor/policy_unpack.c | 4 +- security/keys/encrypted.c | 2 +- security/keys/request_key.c | 2 +- security/keys/request_key_auth.c | 2 +- security/keys/trusted.c | 2 +- 31 files changed, 2918 insertions(+), 2902 deletions(-) delete mode 100644 Documentation/SELinux.txt delete mode 100644 Documentation/Smack.txt delete mode 100644 Documentation/apparmor.txt delete mode 100644 Documentation/credentials.txt delete mode 100644 Documentation/keys-request-key.txt delete mode 100644 Documentation/keys-trusted-encrypted.txt delete mode 100644 Documentation/keys.txt create mode 100644 Documentation/security/00-INDEX create mode 100644 Documentation/security/SELinux.txt create mode 100644 Documentation/security/Smack.txt create mode 100644 Documentation/security/apparmor.txt create mode 100644 Documentation/security/credentials.txt create mode 100644 Documentation/security/keys-request-key.txt create mode 100644 Documentation/security/keys-trusted-encrypted.txt create mode 100644 Documentation/security/keys.txt create mode 100644 Documentation/security/tomoyo.txt delete mode 100644 Documentation/tomoyo.txt (limited to 'scripts') diff --git a/Documentation/00-INDEX b/Documentation/00-INDEX index c17cd4bb2290..c8c1cf631b37 100644 --- a/Documentation/00-INDEX +++ b/Documentation/00-INDEX @@ -192,10 +192,6 @@ kernel-docs.txt - listing of various WWW + books that document kernel internals. kernel-parameters.txt - summary listing of command line / boot prompt args for the kernel. -keys-request-key.txt - - description of the kernel key request service. -keys.txt - - description of the kernel key retention service. kobject.txt - info of the kobject infrastructure of the Linux kernel. kprobes.txt @@ -294,6 +290,8 @@ scheduler/ - directory with info on the scheduler. scsi/ - directory with info on Linux scsi support. +security/ + - directory that contains security-related info serial/ - directory with info on the low level serial API. serial-console.txt diff --git a/Documentation/SELinux.txt b/Documentation/SELinux.txt deleted file mode 100644 index 07eae00f3314..000000000000 --- a/Documentation/SELinux.txt +++ /dev/null @@ -1,27 +0,0 @@ -If you want to use SELinux, chances are you will want -to use the distro-provided policies, or install the -latest reference policy release from - http://oss.tresys.com/projects/refpolicy - -However, if you want to install a dummy policy for -testing, you can do using 'mdp' provided under -scripts/selinux. Note that this requires the selinux -userspace to be installed - in particular you will -need checkpolicy to compile a kernel, and setfiles and -fixfiles to label the filesystem. - - 1. Compile the kernel with selinux enabled. - 2. Type 'make' to compile mdp. - 3. Make sure that you are not running with - SELinux enabled and a real policy. If - you are, reboot with selinux disabled - before continuing. - 4. Run install_policy.sh: - cd scripts/selinux - sh install_policy.sh - -Step 4 will create a new dummy policy valid for your -kernel, with a single selinux user, role, and type. -It will compile the policy, will set your SELINUXTYPE to -dummy in /etc/selinux/config, install the compiled policy -as 'dummy', and relabel your filesystem. diff --git a/Documentation/Smack.txt b/Documentation/Smack.txt deleted file mode 100644 index e9dab41c0fe0..000000000000 --- a/Documentation/Smack.txt +++ /dev/null @@ -1,541 +0,0 @@ - - - "Good for you, you've decided to clean the elevator!" - - The Elevator, from Dark Star - -Smack is the the Simplified Mandatory Access Control Kernel. -Smack is a kernel based implementation of mandatory access -control that includes simplicity in its primary design goals. - -Smack is not the only Mandatory Access Control scheme -available for Linux. Those new to Mandatory Access Control -are encouraged to compare Smack with the other mechanisms -available to determine which is best suited to the problem -at hand. - -Smack consists of three major components: - - The kernel - - A start-up script and a few modified applications - - Configuration data - -The kernel component of Smack is implemented as a Linux -Security Modules (LSM) module. It requires netlabel and -works best with file systems that support extended attributes, -although xattr support is not strictly required. -It is safe to run a Smack kernel under a "vanilla" distribution. -Smack kernels use the CIPSO IP option. Some network -configurations are intolerant of IP options and can impede -access to systems that use them as Smack does. - -The startup script etc-init.d-smack should be installed -in /etc/init.d/smack and should be invoked early in the -start-up process. On Fedora rc5.d/S02smack is recommended. -This script ensures that certain devices have the correct -Smack attributes and loads the Smack configuration if -any is defined. This script invokes two programs that -ensure configuration data is properly formatted. These -programs are /usr/sbin/smackload and /usr/sin/smackcipso. -The system will run just fine without these programs, -but it will be difficult to set access rules properly. - -A version of "ls" that provides a "-M" option to display -Smack labels on long listing is available. - -A hacked version of sshd that allows network logins by users -with specific Smack labels is available. This version does -not work for scp. You must set the /etc/ssh/sshd_config -line: - UsePrivilegeSeparation no - -The format of /etc/smack/usr is: - - username smack - -In keeping with the intent of Smack, configuration data is -minimal and not strictly required. The most important -configuration step is mounting the smackfs pseudo filesystem. - -Add this line to /etc/fstab: - - smackfs /smack smackfs smackfsdef=* 0 0 - -and create the /smack directory for mounting. - -Smack uses extended attributes (xattrs) to store file labels. -The command to set a Smack label on a file is: - - # attr -S -s SMACK64 -V "value" path - -NOTE: Smack labels are limited to 23 characters. The attr command - does not enforce this restriction and can be used to set - invalid Smack labels on files. - -If you don't do anything special all users will get the floor ("_") -label when they log in. If you do want to log in via the hacked ssh -at other labels use the attr command to set the smack value on the -home directory and its contents. - -You can add access rules in /etc/smack/accesses. They take the form: - - subjectlabel objectlabel access - -access is a combination of the letters rwxa which specify the -kind of access permitted a subject with subjectlabel on an -object with objectlabel. If there is no rule no access is allowed. - -A process can see the smack label it is running with by -reading /proc/self/attr/current. A privileged process can -set the process smack by writing there. - -Look for additional programs on http://schaufler-ca.com - -From the Smack Whitepaper: - -The Simplified Mandatory Access Control Kernel - -Casey Schaufler -casey@schaufler-ca.com - -Mandatory Access Control - -Computer systems employ a variety of schemes to constrain how information is -shared among the people and services using the machine. Some of these schemes -allow the program or user to decide what other programs or users are allowed -access to pieces of data. These schemes are called discretionary access -control mechanisms because the access control is specified at the discretion -of the user. Other schemes do not leave the decision regarding what a user or -program can access up to users or programs. These schemes are called mandatory -access control mechanisms because you don't have a choice regarding the users -or programs that have access to pieces of data. - -Bell & LaPadula - -From the middle of the 1980's until the turn of the century Mandatory Access -Control (MAC) was very closely associated with the Bell & LaPadula security -model, a mathematical description of the United States Department of Defense -policy for marking paper documents. MAC in this form enjoyed a following -within the Capital Beltway and Scandinavian supercomputer centers but was -often sited as failing to address general needs. - -Domain Type Enforcement - -Around the turn of the century Domain Type Enforcement (DTE) became popular. -This scheme organizes users, programs, and data into domains that are -protected from each other. This scheme has been widely deployed as a component -of popular Linux distributions. The administrative overhead required to -maintain this scheme and the detailed understanding of the whole system -necessary to provide a secure domain mapping leads to the scheme being -disabled or used in limited ways in the majority of cases. - -Smack - -Smack is a Mandatory Access Control mechanism designed to provide useful MAC -while avoiding the pitfalls of its predecessors. The limitations of Bell & -LaPadula are addressed by providing a scheme whereby access can be controlled -according to the requirements of the system and its purpose rather than those -imposed by an arcane government policy. The complexity of Domain Type -Enforcement and avoided by defining access controls in terms of the access -modes already in use. - -Smack Terminology - -The jargon used to talk about Smack will be familiar to those who have dealt -with other MAC systems and shouldn't be too difficult for the uninitiated to -pick up. There are four terms that are used in a specific way and that are -especially important: - - Subject: A subject is an active entity on the computer system. - On Smack a subject is a task, which is in turn the basic unit - of execution. - - Object: An object is a passive entity on the computer system. - On Smack files of all types, IPC, and tasks can be objects. - - Access: Any attempt by a subject to put information into or get - information from an object is an access. - - Label: Data that identifies the Mandatory Access Control - characteristics of a subject or an object. - -These definitions are consistent with the traditional use in the security -community. There are also some terms from Linux that are likely to crop up: - - Capability: A task that possesses a capability has permission to - violate an aspect of the system security policy, as identified by - the specific capability. A task that possesses one or more - capabilities is a privileged task, whereas a task with no - capabilities is an unprivileged task. - - Privilege: A task that is allowed to violate the system security - policy is said to have privilege. As of this writing a task can - have privilege either by possessing capabilities or by having an - effective user of root. - -Smack Basics - -Smack is an extension to a Linux system. It enforces additional restrictions -on what subjects can access which objects, based on the labels attached to -each of the subject and the object. - -Labels - -Smack labels are ASCII character strings, one to twenty-three characters in -length. Single character labels using special characters, that being anything -other than a letter or digit, are reserved for use by the Smack development -team. Smack labels are unstructured, case sensitive, and the only operation -ever performed on them is comparison for equality. Smack labels cannot -contain unprintable characters, the "/" (slash), the "\" (backslash), the "'" -(quote) and '"' (double-quote) characters. -Smack labels cannot begin with a '-', which is reserved for special options. - -There are some predefined labels: - - _ Pronounced "floor", a single underscore character. - ^ Pronounced "hat", a single circumflex character. - * Pronounced "star", a single asterisk character. - ? Pronounced "huh", a single question mark character. - @ Pronounced "Internet", a single at sign character. - -Every task on a Smack system is assigned a label. System tasks, such as -init(8) and systems daemons, are run with the floor ("_") label. User tasks -are assigned labels according to the specification found in the -/etc/smack/user configuration file. - -Access Rules - -Smack uses the traditional access modes of Linux. These modes are read, -execute, write, and occasionally append. There are a few cases where the -access mode may not be obvious. These include: - - Signals: A signal is a write operation from the subject task to - the object task. - Internet Domain IPC: Transmission of a packet is considered a - write operation from the source task to the destination task. - -Smack restricts access based on the label attached to a subject and the label -attached to the object it is trying to access. The rules enforced are, in -order: - - 1. Any access requested by a task labeled "*" is denied. - 2. A read or execute access requested by a task labeled "^" - is permitted. - 3. A read or execute access requested on an object labeled "_" - is permitted. - 4. Any access requested on an object labeled "*" is permitted. - 5. Any access requested by a task on an object with the same - label is permitted. - 6. Any access requested that is explicitly defined in the loaded - rule set is permitted. - 7. Any other access is denied. - -Smack Access Rules - -With the isolation provided by Smack access separation is simple. There are -many interesting cases where limited access by subjects to objects with -different labels is desired. One example is the familiar spy model of -sensitivity, where a scientist working on a highly classified project would be -able to read documents of lower classifications and anything she writes will -be "born" highly classified. To accommodate such schemes Smack includes a -mechanism for specifying rules allowing access between labels. - -Access Rule Format - -The format of an access rule is: - - subject-label object-label access - -Where subject-label is the Smack label of the task, object-label is the Smack -label of the thing being accessed, and access is a string specifying the sort -of access allowed. The Smack labels are limited to 23 characters. The access -specification is searched for letters that describe access modes: - - a: indicates that append access should be granted. - r: indicates that read access should be granted. - w: indicates that write access should be granted. - x: indicates that execute access should be granted. - -Uppercase values for the specification letters are allowed as well. -Access mode specifications can be in any order. Examples of acceptable rules -are: - - TopSecret Secret rx - Secret Unclass R - Manager Game x - User HR w - New Old rRrRr - Closed Off - - -Examples of unacceptable rules are: - - Top Secret Secret rx - Ace Ace r - Odd spells waxbeans - -Spaces are not allowed in labels. Since a subject always has access to files -with the same label specifying a rule for that case is pointless. Only -valid letters (rwxaRWXA) and the dash ('-') character are allowed in -access specifications. The dash is a placeholder, so "a-r" is the same -as "ar". A lone dash is used to specify that no access should be allowed. - -Applying Access Rules - -The developers of Linux rarely define new sorts of things, usually importing -schemes and concepts from other systems. Most often, the other systems are -variants of Unix. Unix has many endearing properties, but consistency of -access control models is not one of them. Smack strives to treat accesses as -uniformly as is sensible while keeping with the spirit of the underlying -mechanism. - -File system objects including files, directories, named pipes, symbolic links, -and devices require access permissions that closely match those used by mode -bit access. To open a file for reading read access is required on the file. To -search a directory requires execute access. Creating a file with write access -requires both read and write access on the containing directory. Deleting a -file requires read and write access to the file and to the containing -directory. It is possible that a user may be able to see that a file exists -but not any of its attributes by the circumstance of having read access to the -containing directory but not to the differently labeled file. This is an -artifact of the file name being data in the directory, not a part of the file. - -IPC objects, message queues, semaphore sets, and memory segments exist in flat -namespaces and access requests are only required to match the object in -question. - -Process objects reflect tasks on the system and the Smack label used to access -them is the same Smack label that the task would use for its own access -attempts. Sending a signal via the kill() system call is a write operation -from the signaler to the recipient. Debugging a process requires both reading -and writing. Creating a new task is an internal operation that results in two -tasks with identical Smack labels and requires no access checks. - -Sockets are data structures attached to processes and sending a packet from -one process to another requires that the sender have write access to the -receiver. The receiver is not required to have read access to the sender. - -Setting Access Rules - -The configuration file /etc/smack/accesses contains the rules to be set at -system startup. The contents are written to the special file /smack/load. -Rules can be written to /smack/load at any time and take effect immediately. -For any pair of subject and object labels there can be only one rule, with the -most recently specified overriding any earlier specification. - -The program smackload is provided to ensure data is formatted -properly when written to /smack/load. This program reads lines -of the form - - subjectlabel objectlabel mode. - -Task Attribute - -The Smack label of a process can be read from /proc//attr/current. A -process can read its own Smack label from /proc/self/attr/current. A -privileged process can change its own Smack label by writing to -/proc/self/attr/current but not the label of another process. - -File Attribute - -The Smack label of a filesystem object is stored as an extended attribute -named SMACK64 on the file. This attribute is in the security namespace. It can -only be changed by a process with privilege. - -Privilege - -A process with CAP_MAC_OVERRIDE is privileged. - -Smack Networking - -As mentioned before, Smack enforces access control on network protocol -transmissions. Every packet sent by a Smack process is tagged with its Smack -label. This is done by adding a CIPSO tag to the header of the IP packet. Each -packet received is expected to have a CIPSO tag that identifies the label and -if it lacks such a tag the network ambient label is assumed. Before the packet -is delivered a check is made to determine that a subject with the label on the -packet has write access to the receiving process and if that is not the case -the packet is dropped. - -CIPSO Configuration - -It is normally unnecessary to specify the CIPSO configuration. The default -values used by the system handle all internal cases. Smack will compose CIPSO -label values to match the Smack labels being used without administrative -intervention. Unlabeled packets that come into the system will be given the -ambient label. - -Smack requires configuration in the case where packets from a system that is -not smack that speaks CIPSO may be encountered. Usually this will be a Trusted -Solaris system, but there are other, less widely deployed systems out there. -CIPSO provides 3 important values, a Domain Of Interpretation (DOI), a level, -and a category set with each packet. The DOI is intended to identify a group -of systems that use compatible labeling schemes, and the DOI specified on the -smack system must match that of the remote system or packets will be -discarded. The DOI is 3 by default. The value can be read from /smack/doi and -can be changed by writing to /smack/doi. - -The label and category set are mapped to a Smack label as defined in -/etc/smack/cipso. - -A Smack/CIPSO mapping has the form: - - smack level [category [category]*] - -Smack does not expect the level or category sets to be related in any -particular way and does not assume or assign accesses based on them. Some -examples of mappings: - - TopSecret 7 - TS:A,B 7 1 2 - SecBDE 5 2 4 6 - RAFTERS 7 12 26 - -The ":" and "," characters are permitted in a Smack label but have no special -meaning. - -The mapping of Smack labels to CIPSO values is defined by writing to -/smack/cipso. Again, the format of data written to this special file -is highly restrictive, so the program smackcipso is provided to -ensure the writes are done properly. This program takes mappings -on the standard input and sends them to /smack/cipso properly. - -In addition to explicit mappings Smack supports direct CIPSO mappings. One -CIPSO level is used to indicate that the category set passed in the packet is -in fact an encoding of the Smack label. The level used is 250 by default. The -value can be read from /smack/direct and changed by writing to /smack/direct. - -Socket Attributes - -There are two attributes that are associated with sockets. These attributes -can only be set by privileged tasks, but any task can read them for their own -sockets. - - SMACK64IPIN: The Smack label of the task object. A privileged - program that will enforce policy may set this to the star label. - - SMACK64IPOUT: The Smack label transmitted with outgoing packets. - A privileged program may set this to match the label of another - task with which it hopes to communicate. - -Smack Netlabel Exceptions - -You will often find that your labeled application has to talk to the outside, -unlabeled world. To do this there's a special file /smack/netlabel where you can -add some exceptions in the form of : -@IP1 LABEL1 or -@IP2/MASK LABEL2 - -It means that your application will have unlabeled access to @IP1 if it has -write access on LABEL1, and access to the subnet @IP2/MASK if it has write -access on LABEL2. - -Entries in the /smack/netlabel file are matched by longest mask first, like in -classless IPv4 routing. - -A special label '@' and an option '-CIPSO' can be used there : -@ means Internet, any application with any label has access to it --CIPSO means standard CIPSO networking - -If you don't know what CIPSO is and don't plan to use it, you can just do : -echo 127.0.0.1 -CIPSO > /smack/netlabel -echo 0.0.0.0/0 @ > /smack/netlabel - -If you use CIPSO on your 192.168.0.0/16 local network and need also unlabeled -Internet access, you can have : -echo 127.0.0.1 -CIPSO > /smack/netlabel -echo 192.168.0.0/16 -CIPSO > /smack/netlabel -echo 0.0.0.0/0 @ > /smack/netlabel - - -Writing Applications for Smack - -There are three sorts of applications that will run on a Smack system. How an -application interacts with Smack will determine what it will have to do to -work properly under Smack. - -Smack Ignorant Applications - -By far the majority of applications have no reason whatever to care about the -unique properties of Smack. Since invoking a program has no impact on the -Smack label associated with the process the only concern likely to arise is -whether the process has execute access to the program. - -Smack Relevant Applications - -Some programs can be improved by teaching them about Smack, but do not make -any security decisions themselves. The utility ls(1) is one example of such a -program. - -Smack Enforcing Applications - -These are special programs that not only know about Smack, but participate in -the enforcement of system policy. In most cases these are the programs that -set up user sessions. There are also network services that provide information -to processes running with various labels. - -File System Interfaces - -Smack maintains labels on file system objects using extended attributes. The -Smack label of a file, directory, or other file system object can be obtained -using getxattr(2). - - len = getxattr("/", "security.SMACK64", value, sizeof (value)); - -will put the Smack label of the root directory into value. A privileged -process can set the Smack label of a file system object with setxattr(2). - - len = strlen("Rubble"); - rc = setxattr("/foo", "security.SMACK64", "Rubble", len, 0); - -will set the Smack label of /foo to "Rubble" if the program has appropriate -privilege. - -Socket Interfaces - -The socket attributes can be read using fgetxattr(2). - -A privileged process can set the Smack label of outgoing packets with -fsetxattr(2). - - len = strlen("Rubble"); - rc = fsetxattr(fd, "security.SMACK64IPOUT", "Rubble", len, 0); - -will set the Smack label "Rubble" on packets going out from the socket if the -program has appropriate privilege. - - rc = fsetxattr(fd, "security.SMACK64IPIN, "*", strlen("*"), 0); - -will set the Smack label "*" as the object label against which incoming -packets will be checked if the program has appropriate privilege. - -Administration - -Smack supports some mount options: - - smackfsdef=label: specifies the label to give files that lack - the Smack label extended attribute. - - smackfsroot=label: specifies the label to assign the root of the - file system if it lacks the Smack extended attribute. - - smackfshat=label: specifies a label that must have read access to - all labels set on the filesystem. Not yet enforced. - - smackfsfloor=label: specifies a label to which all labels set on the - filesystem must have read access. Not yet enforced. - -These mount options apply to all file system types. - -Smack auditing - -If you want Smack auditing of security events, you need to set CONFIG_AUDIT -in your kernel configuration. -By default, all denied events will be audited. You can change this behavior by -writing a single character to the /smack/logging file : -0 : no logging -1 : log denied (default) -2 : log accepted -3 : log denied & accepted - -Events are logged as 'key=value' pairs, for each event you at least will get -the subjet, the object, the rights requested, the action, the kernel function -that triggered the event, plus other pairs depending on the type of event -audited. diff --git a/Documentation/apparmor.txt b/Documentation/apparmor.txt deleted file mode 100644 index 93c1fd7d0635..000000000000 --- a/Documentation/apparmor.txt +++ /dev/null @@ -1,39 +0,0 @@ ---- What is AppArmor? --- - -AppArmor is MAC style security extension for the Linux kernel. It implements -a task centered policy, with task "profiles" being created and loaded -from user space. Tasks on the system that do not have a profile defined for -them run in an unconfined state which is equivalent to standard Linux DAC -permissions. - ---- How to enable/disable --- - -set CONFIG_SECURITY_APPARMOR=y - -If AppArmor should be selected as the default security module then - set CONFIG_DEFAULT_SECURITY="apparmor" - and CONFIG_SECURITY_APPARMOR_BOOTPARAM_VALUE=1 - -Build the kernel - -If AppArmor is not the default security module it can be enabled by passing -security=apparmor on the kernel's command line. - -If AppArmor is the default security module it can be disabled by passing -apparmor=0, security=XXXX (where XXX is valid security module), on the -kernel's command line - -For AppArmor to enforce any restrictions beyond standard Linux DAC permissions -policy must be loaded into the kernel from user space (see the Documentation -and tools links). - ---- Documentation --- - -Documentation can be found on the wiki. - ---- Links --- - -Mailing List - apparmor@lists.ubuntu.com -Wiki - http://apparmor.wiki.kernel.org/ -User space tools - https://launchpad.net/apparmor -Kernel module - git://git.kernel.org/pub/scm/linux/kernel/git/jj/apparmor-dev.git diff --git a/Documentation/credentials.txt b/Documentation/credentials.txt deleted file mode 100644 index 995baf379c07..000000000000 --- a/Documentation/credentials.txt +++ /dev/null @@ -1,581 +0,0 @@ - ==================== - CREDENTIALS IN LINUX - ==================== - -By: David Howells - -Contents: - - (*) Overview. - - (*) Types of credentials. - - (*) File markings. - - (*) Task credentials. - - - Immutable credentials. - - Accessing task credentials. - - Accessing another task's credentials. - - Altering credentials. - - Managing credentials. - - (*) Open file credentials. - - (*) Overriding the VFS's use of credentials. - - -======== -OVERVIEW -======== - -There are several parts to the security check performed by Linux when one -object acts upon another: - - (1) Objects. - - Objects are things in the system that may be acted upon directly by - userspace programs. Linux has a variety of actionable objects, including: - - - Tasks - - Files/inodes - - Sockets - - Message queues - - Shared memory segments - - Semaphores - - Keys - - As a part of the description of all these objects there is a set of - credentials. What's in the set depends on the type of object. - - (2) Object ownership. - - Amongst the credentials of most objects, there will be a subset that - indicates the ownership of that object. This is used for resource - accounting and limitation (disk quotas and task rlimits for example). - - In a standard UNIX filesystem, for instance, this will be defined by the - UID marked on the inode. - - (3) The objective context. - - Also amongst the credentials of those objects, there will be a subset that - indicates the 'objective context' of that object. This may or may not be - the same set as in (2) - in standard UNIX files, for instance, this is the - defined by the UID and the GID marked on the inode. - - The objective context is used as part of the security calculation that is - carried out when an object is acted upon. - - (4) Subjects. - - A subject is an object that is acting upon another object. - - Most of the objects in the system are inactive: they don't act on other - objects within the system. Processes/tasks are the obvious exception: - they do stuff; they access and manipulate things. - - Objects other than tasks may under some circumstances also be subjects. - For instance an open file may send SIGIO to a task using the UID and EUID - given to it by a task that called fcntl(F_SETOWN) upon it. In this case, - the file struct will have a subjective context too. - - (5) The subjective context. - - A subject has an additional interpretation of its credentials. A subset - of its credentials forms the 'subjective context'. The subjective context - is used as part of the security calculation that is carried out when a - subject acts. - - A Linux task, for example, has the FSUID, FSGID and the supplementary - group list for when it is acting upon a file - which are quite separate - from the real UID and GID that normally form the objective context of the - task. - - (6) Actions. - - Linux has a number of actions available that a subject may perform upon an - object. The set of actions available depends on the nature of the subject - and the object. - - Actions include reading, writing, creating and deleting files; forking or - signalling and tracing tasks. - - (7) Rules, access control lists and security calculations. - - When a subject acts upon an object, a security calculation is made. This - involves taking the subjective context, the objective context and the - action, and searching one or more sets of rules to see whether the subject - is granted or denied permission to act in the desired manner on the - object, given those contexts. - - There are two main sources of rules: - - (a) Discretionary access control (DAC): - - Sometimes the object will include sets of rules as part of its - description. This is an 'Access Control List' or 'ACL'. A Linux - file may supply more than one ACL. - - A traditional UNIX file, for example, includes a permissions mask that - is an abbreviated ACL with three fixed classes of subject ('user', - 'group' and 'other'), each of which may be granted certain privileges - ('read', 'write' and 'execute' - whatever those map to for the object - in question). UNIX file permissions do not allow the arbitrary - specification of subjects, however, and so are of limited use. - - A Linux file might also sport a POSIX ACL. This is a list of rules - that grants various permissions to arbitrary subjects. - - (b) Mandatory access control (MAC): - - The system as a whole may have one or more sets of rules that get - applied to all subjects and objects, regardless of their source. - SELinux and Smack are examples of this. - - In the case of SELinux and Smack, each object is given a label as part - of its credentials. When an action is requested, they take the - subject label, the object label and the action and look for a rule - that says that this action is either granted or denied. - - -==================== -TYPES OF CREDENTIALS -==================== - -The Linux kernel supports the following types of credentials: - - (1) Traditional UNIX credentials. - - Real User ID - Real Group ID - - The UID and GID are carried by most, if not all, Linux objects, even if in - some cases it has to be invented (FAT or CIFS files for example, which are - derived from Windows). These (mostly) define the objective context of - that object, with tasks being slightly different in some cases. - - Effective, Saved and FS User ID - Effective, Saved and FS Group ID - Supplementary groups - - These are additional credentials used by tasks only. Usually, an - EUID/EGID/GROUPS will be used as the subjective context, and real UID/GID - will be used as the objective. For tasks, it should be noted that this is - not always true. - - (2) Capabilities. - - Set of permitted capabilities - Set of inheritable capabilities - Set of effective capabilities - Capability bounding set - - These are only carried by tasks. They indicate superior capabilities - granted piecemeal to a task that an ordinary task wouldn't otherwise have. - These are manipulated implicitly by changes to the traditional UNIX - credentials, but can also be manipulated directly by the capset() system - call. - - The permitted capabilities are those caps that the process might grant - itself to its effective or permitted sets through capset(). This - inheritable set might also be so constrained. - - The effective capabilities are the ones that a task is actually allowed to - make use of itself. - - The inheritable capabilities are the ones that may get passed across - execve(). - - The bounding set limits the capabilities that may be inherited across - execve(), especially when a binary is executed that will execute as UID 0. - - (3) Secure management flags (securebits). - - These are only carried by tasks. These govern the way the above - credentials are manipulated and inherited over certain operations such as - execve(). They aren't used directly as objective or subjective - credentials. - - (4) Keys and keyrings. - - These are only carried by tasks. They carry and cache security tokens - that don't fit into the other standard UNIX credentials. They are for - making such things as network filesystem keys available to the file - accesses performed by processes, without the necessity of ordinary - programs having to know about security details involved. - - Keyrings are a special type of key. They carry sets of other keys and can - be searched for the desired key. Each process may subscribe to a number - of keyrings: - - Per-thread keying - Per-process keyring - Per-session keyring - - When a process accesses a key, if not already present, it will normally be - cached on one of these keyrings for future accesses to find. - - For more information on using keys, see Documentation/keys.txt. - - (5) LSM - - The Linux Security Module allows extra controls to be placed over the - operations that a task may do. Currently Linux supports two main - alternate LSM options: SELinux and Smack. - - Both work by labelling the objects in a system and then applying sets of - rules (policies) that say what operations a task with one label may do to - an object with another label. - - (6) AF_KEY - - This is a socket-based approach to credential management for networking - stacks [RFC 2367]. It isn't discussed by this document as it doesn't - interact directly with task and file credentials; rather it keeps system - level credentials. - - -When a file is opened, part of the opening task's subjective context is -recorded in the file struct created. This allows operations using that file -struct to use those credentials instead of the subjective context of the task -that issued the operation. An example of this would be a file opened on a -network filesystem where the credentials of the opened file should be presented -to the server, regardless of who is actually doing a read or a write upon it. - - -============= -FILE MARKINGS -============= - -Files on disk or obtained over the network may have annotations that form the -objective security context of that file. Depending on the type of filesystem, -this may include one or more of the following: - - (*) UNIX UID, GID, mode; - - (*) Windows user ID; - - (*) Access control list; - - (*) LSM security label; - - (*) UNIX exec privilege escalation bits (SUID/SGID); - - (*) File capabilities exec privilege escalation bits. - -These are compared to the task's subjective security context, and certain -operations allowed or disallowed as a result. In the case of execve(), the -privilege escalation bits come into play, and may allow the resulting process -extra privileges, based on the annotations on the executable file. - - -================ -TASK CREDENTIALS -================ - -In Linux, all of a task's credentials are held in (uid, gid) or through -(groups, keys, LSM security) a refcounted structure of type 'struct cred'. -Each task points to its credentials by a pointer called 'cred' in its -task_struct. - -Once a set of credentials has been prepared and committed, it may not be -changed, barring the following exceptions: - - (1) its reference count may be changed; - - (2) the reference count on the group_info struct it points to may be changed; - - (3) the reference count on the security data it points to may be changed; - - (4) the reference count on any keyrings it points to may be changed; - - (5) any keyrings it points to may be revoked, expired or have their security - attributes changed; and - - (6) the contents of any keyrings to which it points may be changed (the whole - point of keyrings being a shared set of credentials, modifiable by anyone - with appropriate access). - -To alter anything in the cred struct, the copy-and-replace principle must be -adhered to. First take a copy, then alter the copy and then use RCU to change -the task pointer to make it point to the new copy. There are wrappers to aid -with this (see below). - -A task may only alter its _own_ credentials; it is no longer permitted for a -task to alter another's credentials. This means the capset() system call is no -longer permitted to take any PID other than the one of the current process. -Also keyctl_instantiate() and keyctl_negate() functions no longer permit -attachment to process-specific keyrings in the requesting process as the -instantiating process may need to create them. - - -IMMUTABLE CREDENTIALS ---------------------- - -Once a set of credentials has been made public (by calling commit_creds() for -example), it must be considered immutable, barring two exceptions: - - (1) The reference count may be altered. - - (2) Whilst the keyring subscriptions of a set of credentials may not be - changed, the keyrings subscribed to may have their contents altered. - -To catch accidental credential alteration at compile time, struct task_struct -has _const_ pointers to its credential sets, as does struct file. Furthermore, -certain functions such as get_cred() and put_cred() operate on const pointers, -thus rendering casts unnecessary, but require to temporarily ditch the const -qualification to be able to alter the reference count. - - -ACCESSING TASK CREDENTIALS --------------------------- - -A task being able to alter only its own credentials permits the current process -to read or replace its own credentials without the need for any form of locking -- which simplifies things greatly. It can just call: - - const struct cred *current_cred() - -to get a pointer to its credentials structure, and it doesn't have to release -it afterwards. - -There are convenience wrappers for retrieving specific aspects of a task's -credentials (the value is simply returned in each case): - - uid_t current_uid(void) Current's real UID - gid_t current_gid(void) Current's real GID - uid_t current_euid(void) Current's effective UID - gid_t current_egid(void) Current's effective GID - uid_t current_fsuid(void) Current's file access UID - gid_t current_fsgid(void) Current's file access GID - kernel_cap_t current_cap(void) Current's effective capabilities - void *current_security(void) Current's LSM security pointer - struct user_struct *current_user(void) Current's user account - -There are also convenience wrappers for retrieving specific associated pairs of -a task's credentials: - - void current_uid_gid(uid_t *, gid_t *); - void current_euid_egid(uid_t *, gid_t *); - void current_fsuid_fsgid(uid_t *, gid_t *); - -which return these pairs of values through their arguments after retrieving -them from the current task's credentials. - - -In addition, there is a function for obtaining a reference on the current -process's current set of credentials: - - const struct cred *get_current_cred(void); - -and functions for getting references to one of the credentials that don't -actually live in struct cred: - - struct user_struct *get_current_user(void); - struct group_info *get_current_groups(void); - -which get references to the current process's user accounting structure and -supplementary groups list respectively. - -Once a reference has been obtained, it must be released with put_cred(), -free_uid() or put_group_info() as appropriate. - - -ACCESSING ANOTHER TASK'S CREDENTIALS ------------------------------------- - -Whilst a task may access its own credentials without the need for locking, the -same is not true of a task wanting to access another task's credentials. It -must use the RCU read lock and rcu_dereference(). - -The rcu_dereference() is wrapped by: - - const struct cred *__task_cred(struct task_struct *task); - -This should be used inside the RCU read lock, as in the following example: - - void foo(struct task_struct *t, struct foo_data *f) - { - const struct cred *tcred; - ... - rcu_read_lock(); - tcred = __task_cred(t); - f->uid = tcred->uid; - f->gid = tcred->gid; - f->groups = get_group_info(tcred->groups); - rcu_read_unlock(); - ... - } - -Should it be necessary to hold another task's credentials for a long period of -time, and possibly to sleep whilst doing so, then the caller should get a -reference on them using: - - const struct cred *get_task_cred(struct task_struct *task); - -This does all the RCU magic inside of it. The caller must call put_cred() on -the credentials so obtained when they're finished with. - - [*] Note: The result of __task_cred() should not be passed directly to - get_cred() as this may race with commit_cred(). - -There are a couple of convenience functions to access bits of another task's -credentials, hiding the RCU magic from the caller: - - uid_t task_uid(task) Task's real UID - uid_t task_euid(task) Task's effective UID - -If the caller is holding the RCU read lock at the time anyway, then: - - __task_cred(task)->uid - __task_cred(task)->euid - -should be used instead. Similarly, if multiple aspects of a task's credentials -need to be accessed, RCU read lock should be used, __task_cred() called, the -result stored in a temporary pointer and then the credential aspects called -from that before dropping the lock. This prevents the potentially expensive -RCU magic from being invoked multiple times. - -Should some other single aspect of another task's credentials need to be -accessed, then this can be used: - - task_cred_xxx(task, member) - -where 'member' is a non-pointer member of the cred struct. For instance: - - uid_t task_cred_xxx(task, suid); - -will retrieve 'struct cred::suid' from the task, doing the appropriate RCU -magic. This may not be used for pointer members as what they point to may -disappear the moment the RCU read lock is dropped. - - -ALTERING CREDENTIALS --------------------- - -As previously mentioned, a task may only alter its own credentials, and may not -alter those of another task. This means that it doesn't need to use any -locking to alter its own credentials. - -To alter the current process's credentials, a function should first prepare a -new set of credentials by calling: - - struct cred *prepare_creds(void); - -this locks current->cred_replace_mutex and then allocates and constructs a -duplicate of the current process's credentials, returning with the mutex still -held if successful. It returns NULL if not successful (out of memory). - -The mutex prevents ptrace() from altering the ptrace state of a process whilst -security checks on credentials construction and changing is taking place as -the ptrace state may alter the outcome, particularly in the case of execve(). - -The new credentials set should be altered appropriately, and any security -checks and hooks done. Both the current and the proposed sets of credentials -are available for this purpose as current_cred() will return the current set -still at this point. - - -When the credential set is ready, it should be committed to the current process -by calling: - - int commit_creds(struct cred *new); - -This will alter various aspects of the credentials and the process, giving the -LSM a chance to do likewise, then it will use rcu_assign_pointer() to actually -commit the new credentials to current->cred, it will release -current->cred_replace_mutex to allow ptrace() to take place, and it will notify -the scheduler and others of the changes. - -This function is guaranteed to return 0, so that it can be tail-called at the -end of such functions as sys_setresuid(). - -Note that this function consumes the caller's reference to the new credentials. -The caller should _not_ call put_cred() on the new credentials afterwards. - -Furthermore, once this function has been called on a new set of credentials, -those credentials may _not_ be changed further. - - -Should the security checks fail or some other error occur after prepare_creds() -has been called, then the following function should be invoked: - - void abort_creds(struct cred *new); - -This releases the lock on current->cred_replace_mutex that prepare_creds() got -and then releases the new credentials. - - -A typical credentials alteration function would look something like this: - - int alter_suid(uid_t suid) - { - struct cred *new; - int ret; - - new = prepare_creds(); - if (!new) - return -ENOMEM; - - new->suid = suid; - ret = security_alter_suid(new); - if (ret < 0) { - abort_creds(new); - return ret; - } - - return commit_creds(new); - } - - -MANAGING CREDENTIALS --------------------- - -There are some functions to help manage credentials: - - (*) void put_cred(const struct cred *cred); - - This releases a reference to the given set of credentials. If the - reference count reaches zero, the credentials will be scheduled for - destruction by the RCU system. - - (*) const struct cred *get_cred(const struct cred *cred); - - This gets a reference on a live set of credentials, returning a pointer to - that set of credentials. - - (*) struct cred *get_new_cred(struct cred *cred); - - This gets a reference on a set of credentials that is under construction - and is thus still mutable, returning a pointer to that set of credentials. - - -===================== -OPEN FILE CREDENTIALS -===================== - -When a new file is opened, a reference is obtained on the opening task's -credentials and this is attached to the file struct as 'f_cred' in place of -'f_uid' and 'f_gid'. Code that used to access file->f_uid and file->f_gid -should now access file->f_cred->fsuid and file->f_cred->fsgid. - -It is safe to access f_cred without the use of RCU or locking because the -pointer will not change over the lifetime of the file struct, and nor will the -contents of the cred struct pointed to, barring the exceptions listed above -(see the Task Credentials section). - - -======================================= -OVERRIDING THE VFS'S USE OF CREDENTIALS -======================================= - -Under some circumstances it is desirable to override the credentials used by -the VFS, and that can be done by calling into such as vfs_mkdir() with a -different set of credentials. This is done in the following places: - - (*) sys_faccessat(). - - (*) do_coredump(). - - (*) nfs4recover.c. diff --git a/Documentation/filesystems/nfs/idmapper.txt b/Documentation/filesystems/nfs/idmapper.txt index b9b4192ea8b5..9c8fd6148656 100644 --- a/Documentation/filesystems/nfs/idmapper.txt +++ b/Documentation/filesystems/nfs/idmapper.txt @@ -47,8 +47,8 @@ request-key will find the first matching line and corresponding program. In this case, /some/other/program will handle all uid lookups and /usr/sbin/nfs.idmap will handle gid, user, and group lookups. -See for more information about the -request-key function. +See for more information +about the request-key function. ========= diff --git a/Documentation/keys-request-key.txt b/Documentation/keys-request-key.txt deleted file mode 100644 index 69686ad12c66..000000000000 --- a/Documentation/keys-request-key.txt +++ /dev/null @@ -1,202 +0,0 @@ - =================== - KEY REQUEST SERVICE - =================== - -The key request service is part of the key retention service (refer to -Documentation/keys.txt). This document explains more fully how the requesting -algorithm works. - -The process starts by either the kernel requesting a service by calling -request_key*(): - - struct key *request_key(const struct key_type *type, - const char *description, - const char *callout_info); - -or: - - struct key *request_key_with_auxdata(const struct key_type *type, - const char *description, - const char *callout_info, - size_t callout_len, - void *aux); - -or: - - struct key *request_key_async(const struct key_type *type, - const char *description, - const char *callout_info, - size_t callout_len); - -or: - - struct key *request_key_async_with_auxdata(const struct key_type *type, - const char *description, - const char *callout_info, - size_t callout_len, - void *aux); - -Or by userspace invoking the request_key system call: - - key_serial_t request_key(const char *type, - const char *description, - const char *callout_info, - key_serial_t dest_keyring); - -The main difference between the access points is that the in-kernel interface -does not need to link the key to a keyring to prevent it from being immediately -destroyed. The kernel interface returns a pointer directly to the key, and -it's up to the caller to destroy the key. - -The request_key*_with_auxdata() calls are like the in-kernel request_key*() -calls, except that they permit auxiliary data to be passed to the upcaller (the -default is NULL). This is only useful for those key types that define their -own upcall mechanism rather than using /sbin/request-key. - -The two async in-kernel calls may return keys that are still in the process of -being constructed. The two non-async ones will wait for construction to -complete first. - -The userspace interface links the key to a keyring associated with the process -to prevent the key from going away, and returns the serial number of the key to -the caller. - - -The following example assumes that the key types involved don't define their -own upcall mechanisms. If they do, then those should be substituted for the -forking and execution of /sbin/request-key. - - -=========== -THE PROCESS -=========== - -A request proceeds in the following manner: - - (1) Process A calls request_key() [the userspace syscall calls the kernel - interface]. - - (2) request_key() searches the process's subscribed keyrings to see if there's - a suitable key there. If there is, it returns the key. If there isn't, - and callout_info is not set, an error is returned. Otherwise the process - proceeds to the next step. - - (3) request_key() sees that A doesn't have the desired key yet, so it creates - two things: - - (a) An uninstantiated key U of requested type and description. - - (b) An authorisation key V that refers to key U and notes that process A - is the context in which key U should be instantiated and secured, and - from which associated key requests may be satisfied. - - (4) request_key() then forks and executes /sbin/request-key with a new session - keyring that contains a link to auth key V. - - (5) /sbin/request-key assumes the authority associated with key U. - - (6) /sbin/request-key execs an appropriate program to perform the actual - instantiation. - - (7) The program may want to access another key from A's context (say a - Kerberos TGT key). It just requests the appropriate key, and the keyring - search notes that the session keyring has auth key V in its bottom level. - - This will permit it to then search the keyrings of process A with the - UID, GID, groups and security info of process A as if it was process A, - and come up with key W. - - (8) The program then does what it must to get the data with which to - instantiate key U, using key W as a reference (perhaps it contacts a - Kerberos server using the TGT) and then instantiates key U. - - (9) Upon instantiating key U, auth key V is automatically revoked so that it - may not be used again. - -(10) The program then exits 0 and request_key() deletes key V and returns key - U to the caller. - -This also extends further. If key W (step 7 above) didn't exist, key W would -be created uninstantiated, another auth key (X) would be created (as per step -3) and another copy of /sbin/request-key spawned (as per step 4); but the -context specified by auth key X will still be process A, as it was in auth key -V. - -This is because process A's keyrings can't simply be attached to -/sbin/request-key at the appropriate places because (a) execve will discard two -of them, and (b) it requires the same UID/GID/Groups all the way through. - - -==================================== -NEGATIVE INSTANTIATION AND REJECTION -==================================== - -Rather than instantiating a key, it is possible for the possessor of an -authorisation key to negatively instantiate a key that's under construction. -This is a short duration placeholder that causes any attempt at re-requesting -the key whilst it exists to fail with error ENOKEY if negated or the specified -error if rejected. - -This is provided to prevent excessive repeated spawning of /sbin/request-key -processes for a key that will never be obtainable. - -Should the /sbin/request-key process exit anything other than 0 or die on a -signal, the key under construction will be automatically negatively -instantiated for a short amount of time. - - -==================== -THE SEARCH ALGORITHM -==================== - -A search of any particular keyring proceeds in the following fashion: - - (1) When the key management code searches for a key (keyring_search_aux) it - firstly calls key_permission(SEARCH) on the keyring it's starting with, - if this denies permission, it doesn't search further. - - (2) It considers all the non-keyring keys within that keyring and, if any key - matches the criteria specified, calls key_permission(SEARCH) on it to see - if the key is allowed to be found. If it is, that key is returned; if - not, the search continues, and the error code is retained if of higher - priority than the one currently set. - - (3) It then considers all the keyring-type keys in the keyring it's currently - searching. It calls key_permission(SEARCH) on each keyring, and if this - grants permission, it recurses, executing steps (2) and (3) on that - keyring. - -The process stops immediately a valid key is found with permission granted to -use it. Any error from a previous match attempt is discarded and the key is -returned. - -When search_process_keyrings() is invoked, it performs the following searches -until one succeeds: - - (1) If extant, the process's thread keyring is searched. - - (2) If extant, the process's process keyring is searched. - - (3) The process's session keyring is searched. - - (4) If the process has assumed the authority associated with a request_key() - authorisation key then: - - (a) If extant, the calling process's thread keyring is searched. - - (b) If extant, the calling process's process keyring is searched. - - (c) The calling process's session keyring is searched. - -The moment one succeeds, all pending errors are discarded and the found key is -returned. - -Only if all these fail does the whole thing fail with the highest priority -error. Note that several errors may have come from LSM. - -The error priority is: - - EKEYREVOKED > EKEYEXPIRED > ENOKEY - -EACCES/EPERM are only returned on a direct search of a specific keyring where -the basal keyring does not grant Search permission. diff --git a/Documentation/keys-trusted-encrypted.txt b/Documentation/keys-trusted-encrypted.txt deleted file mode 100644 index 8fb79bc1ac4b..000000000000 --- a/Documentation/keys-trusted-encrypted.txt +++ /dev/null @@ -1,145 +0,0 @@ - Trusted and Encrypted Keys - -Trusted and Encrypted Keys are two new key types added to the existing kernel -key ring service. Both of these new types are variable length symmetic keys, -and in both cases all keys are created in the kernel, and user space sees, -stores, and loads only encrypted blobs. Trusted Keys require the availability -of a Trusted Platform Module (TPM) chip for greater security, while Encrypted -Keys can be used on any system. All user level blobs, are displayed and loaded -in hex ascii for convenience, and are integrity verified. - -Trusted Keys use a TPM both to generate and to seal the keys. Keys are sealed -under a 2048 bit RSA key in the TPM, and optionally sealed to specified PCR -(integrity measurement) values, and only unsealed by the TPM, if PCRs and blob -integrity verifications match. A loaded Trusted Key can be updated with new -(future) PCR values, so keys are easily migrated to new pcr values, such as -when the kernel and initramfs are updated. The same key can have many saved -blobs under different PCR values, so multiple boots are easily supported. - -By default, trusted keys are sealed under the SRK, which has the default -authorization value (20 zeros). This can be set at takeownership time with the -trouser's utility: "tpm_takeownership -u -z". - -Usage: - keyctl add trusted name "new keylen [options]" ring - keyctl add trusted name "load hex_blob [pcrlock=pcrnum]" ring - keyctl update key "update [options]" - keyctl print keyid - - options: - keyhandle= ascii hex value of sealing key default 0x40000000 (SRK) - keyauth= ascii hex auth for sealing key default 0x00...i - (40 ascii zeros) - blobauth= ascii hex auth for sealed data default 0x00... - (40 ascii zeros) - blobauth= ascii hex auth for sealed data default 0x00... - (40 ascii zeros) - pcrinfo= ascii hex of PCR_INFO or PCR_INFO_LONG (no default) - pcrlock= pcr number to be extended to "lock" blob - migratable= 0|1 indicating permission to reseal to new PCR values, - default 1 (resealing allowed) - -"keyctl print" returns an ascii hex copy of the sealed key, which is in standard -TPM_STORED_DATA format. The key length for new keys are always in bytes. -Trusted Keys can be 32 - 128 bytes (256 - 1024 bits), the upper limit is to fit -within the 2048 bit SRK (RSA) keylength, with all necessary structure/padding. - -Encrypted keys do not depend on a TPM, and are faster, as they use AES for -encryption/decryption. New keys are created from kernel generated random -numbers, and are encrypted/decrypted using a specified 'master' key. The -'master' key can either be a trusted-key or user-key type. The main -disadvantage of encrypted keys is that if they are not rooted in a trusted key, -they are only as secure as the user key encrypting them. The master user key -should therefore be loaded in as secure a way as possible, preferably early in -boot. - -Usage: - keyctl add encrypted name "new key-type:master-key-name keylen" ring - keyctl add encrypted name "load hex_blob" ring - keyctl update keyid "update key-type:master-key-name" - -where 'key-type' is either 'trusted' or 'user'. - -Examples of trusted and encrypted key usage: - -Create and save a trusted key named "kmk" of length 32 bytes: - - $ keyctl add trusted kmk "new 32" @u - 440502848 - - $ keyctl show - Session Keyring - -3 --alswrv 500 500 keyring: _ses - 97833714 --alswrv 500 -1 \_ keyring: _uid.500 - 440502848 --alswrv 500 500 \_ trusted: kmk - - $ keyctl print 440502848 - 0101000000000000000001005d01b7e3f4a6be5709930f3b70a743cbb42e0cc95e18e915 - 3f60da455bbf1144ad12e4f92b452f966929f6105fd29ca28e4d4d5a031d068478bacb0b - 27351119f822911b0a11ba3d3498ba6a32e50dac7f32894dd890eb9ad578e4e292c83722 - a52e56a097e6a68b3f56f7a52ece0cdccba1eb62cad7d817f6dc58898b3ac15f36026fec - d568bd4a706cb60bb37be6d8f1240661199d640b66fb0fe3b079f97f450b9ef9c22c6d5d - dd379f0facd1cd020281dfa3c70ba21a3fa6fc2471dc6d13ecf8298b946f65345faa5ef0 - f1f8fff03ad0acb083725535636addb08d73dedb9832da198081e5deae84bfaf0409c22b - e4a8aea2b607ec96931e6f4d4fe563ba - - $ keyctl pipe 440502848 > kmk.blob - -Load a trusted key from the saved blob: - - $ keyctl add trusted kmk "load `cat kmk.blob`" @u - 268728824 - - $ keyctl print 268728824 - 0101000000000000000001005d01b7e3f4a6be5709930f3b70a743cbb42e0cc95e18e915 - 3f60da455bbf1144ad12e4f92b452f966929f6105fd29ca28e4d4d5a031d068478bacb0b - 27351119f822911b0a11ba3d3498ba6a32e50dac7f32894dd890eb9ad578e4e292c83722 - a52e56a097e6a68b3f56f7a52ece0cdccba1eb62cad7d817f6dc58898b3ac15f36026fec - d568bd4a706cb60bb37be6d8f1240661199d640b66fb0fe3b079f97f450b9ef9c22c6d5d - dd379f0facd1cd020281dfa3c70ba21a3fa6fc2471dc6d13ecf8298b946f65345faa5ef0 - f1f8fff03ad0acb083725535636addb08d73dedb9832da198081e5deae84bfaf0409c22b - e4a8aea2b607ec96931e6f4d4fe563ba - -Reseal a trusted key under new pcr values: - - $ keyctl update 268728824 "update pcrinfo=`cat pcr.blob`" - $ keyctl print 268728824 - 010100000000002c0002800093c35a09b70fff26e7a98ae786c641e678ec6ffb6b46d805 - 77c8a6377aed9d3219c6dfec4b23ffe3000001005d37d472ac8a44023fbb3d18583a4f73 - d3a076c0858f6f1dcaa39ea0f119911ff03f5406df4f7f27f41da8d7194f45c9f4e00f2e - df449f266253aa3f52e55c53de147773e00f0f9aca86c64d94c95382265968c354c5eab4 - 9638c5ae99c89de1e0997242edfb0b501744e11ff9762dfd951cffd93227cc513384e7e6 - e782c29435c7ec2edafaa2f4c1fe6e7a781b59549ff5296371b42133777dcc5b8b971610 - 94bc67ede19e43ddb9dc2baacad374a36feaf0314d700af0a65c164b7082401740e489c9 - 7ef6a24defe4846104209bf0c3eced7fa1a672ed5b125fc9d8cd88b476a658a4434644ef - df8ae9a178e9f83ba9f08d10fa47e4226b98b0702f06b3b8 - -Create and save an encrypted key "evm" using the above trusted key "kmk": - - $ keyctl add encrypted evm "new trusted:kmk 32" @u - 159771175 - - $ keyctl print 159771175 - trusted:kmk 32 2375725ad57798846a9bbd240de8906f006e66c03af53b1b382dbbc55 - be2a44616e4959430436dc4f2a7a9659aa60bb4652aeb2120f149ed197c564e024717c64 - 5972dcb82ab2dde83376d82b2e3c09ffc - - $ keyctl pipe 159771175 > evm.blob - -Load an encrypted key "evm" from saved blob: - - $ keyctl add encrypted evm "load `cat evm.blob`" @u - 831684262 - - $ keyctl print 831684262 - trusted:kmk 32 2375725ad57798846a9bbd240de8906f006e66c03af53b1b382dbbc55 - be2a44616e4959430436dc4f2a7a9659aa60bb4652aeb2120f149ed197c564e024717c64 - 5972dcb82ab2dde83376d82b2e3c09ffc - - -The initial consumer of trusted keys is EVM, which at boot time needs a high -quality symmetric key for HMAC protection of file metadata. The use of a -trusted key provides strong guarantees that the EVM key has not been -compromised by a user level problem, and when sealed to specific boot PCR -values, protects against boot and offline attacks. Other uses for trusted and -encrypted keys, such as for disk and file encryption are anticipated. diff --git a/Documentation/keys.txt b/Documentation/keys.txt deleted file mode 100644 index 6523a9e6f293..000000000000 --- a/Documentation/keys.txt +++ /dev/null @@ -1,1290 +0,0 @@ - ============================ - KERNEL KEY RETENTION SERVICE - ============================ - -This service allows cryptographic keys, authentication tokens, cross-domain -user mappings, and similar to be cached in the kernel for the use of -filesystems and other kernel services. - -Keyrings are permitted; these are a special type of key that can hold links to -other keys. Processes each have three standard keyring subscriptions that a -kernel service can search for relevant keys. - -The key service can be configured on by enabling: - - "Security options"/"Enable access key retention support" (CONFIG_KEYS) - -This document has the following sections: - - - Key overview - - Key service overview - - Key access permissions - - SELinux support - - New procfs files - - Userspace system call interface - - Kernel services - - Notes on accessing payload contents - - Defining a key type - - Request-key callback service - - Garbage collection - - -============ -KEY OVERVIEW -============ - -In this context, keys represent units of cryptographic data, authentication -tokens, keyrings, etc.. These are represented in the kernel by struct key. - -Each key has a number of attributes: - - - A serial number. - - A type. - - A description (for matching a key in a search). - - Access control information. - - An expiry time. - - A payload. - - State. - - - (*) Each key is issued a serial number of type key_serial_t that is unique for - the lifetime of that key. All serial numbers are positive non-zero 32-bit - integers. - - Userspace programs can use a key's serial numbers as a way to gain access - to it, subject to permission checking. - - (*) Each key is of a defined "type". Types must be registered inside the - kernel by a kernel service (such as a filesystem) before keys of that type - can be added or used. Userspace programs cannot define new types directly. - - Key types are represented in the kernel by struct key_type. This defines a - number of operations that can be performed on a key of that type. - - Should a type be removed from the system, all the keys of that type will - be invalidated. - - (*) Each key has a description. This should be a printable string. The key - type provides an operation to perform a match between the description on a - key and a criterion string. - - (*) Each key has an owner user ID, a group ID and a permissions mask. These - are used to control what a process may do to a key from userspace, and - whether a kernel service will be able to find the key. - - (*) Each key can be set to expire at a specific time by the key type's - instantiation function. Keys can also be immortal. - - (*) Each key can have a payload. This is a quantity of data that represent the - actual "key". In the case of a keyring, this is a list of keys to which - the keyring links; in the case of a user-defined key, it's an arbitrary - blob of data. - - Having a payload is not required; and the payload can, in fact, just be a - value stored in the struct key itself. - - When a key is instantiated, the key type's instantiation function is - called with a blob of data, and that then creates the key's payload in - some way. - - Similarly, when userspace wants to read back the contents of the key, if - permitted, another key type operation will be called to convert the key's - attached payload back into a blob of data. - - (*) Each key can be in one of a number of basic states: - - (*) Uninstantiated. The key exists, but does not have any data attached. - Keys being requested from userspace will be in this state. - - (*) Instantiated. This is the normal state. The key is fully formed, and - has data attached. - - (*) Negative. This is a relatively short-lived state. The key acts as a - note saying that a previous call out to userspace failed, and acts as - a throttle on key lookups. A negative key can be updated to a normal - state. - - (*) Expired. Keys can have lifetimes set. If their lifetime is exceeded, - they traverse to this state. An expired key can be updated back to a - normal state. - - (*) Revoked. A key is put in this state by userspace action. It can't be - found or operated upon (apart from by unlinking it). - - (*) Dead. The key's type was unregistered, and so the key is now useless. - -Keys in the last three states are subject to garbage collection. See the -section on "Garbage collection". - - -==================== -KEY SERVICE OVERVIEW -==================== - -The key service provides a number of features besides keys: - - (*) The key service defines two special key types: - - (+) "keyring" - - Keyrings are special keys that contain a list of other keys. Keyring - lists can be modified using various system calls. Keyrings should not - be given a payload when created. - - (+) "user" - - A key of this type has a description and a payload that are arbitrary - blobs of data. These can be created, updated and read by userspace, - and aren't intended for use by kernel services. - - (*) Each process subscribes to three keyrings: a thread-specific keyring, a - process-specific keyring, and a session-specific keyring. - - The thread-specific keyring is discarded from the child when any sort of - clone, fork, vfork or execve occurs. A new keyring is created only when - required. - - The process-specific keyring is replaced with an empty one in the child on - clone, fork, vfork unless CLONE_THREAD is supplied, in which case it is - shared. execve also discards the process's process keyring and creates a - new one. - - The session-specific keyring is persistent across clone, fork, vfork and - execve, even when the latter executes a set-UID or set-GID binary. A - process can, however, replace its current session keyring with a new one - by using PR_JOIN_SESSION_KEYRING. It is permitted to request an anonymous - new one, or to attempt to create or join one of a specific name. - - The ownership of the thread keyring changes when the real UID and GID of - the thread changes. - - (*) Each user ID resident in the system holds two special keyrings: a user - specific keyring and a default user session keyring. The default session - keyring is initialised with a link to the user-specific keyring. - - When a process changes its real UID, if it used to have no session key, it - will be subscribed to the default session key for the new UID. - - If a process attempts to access its session key when it doesn't have one, - it will be subscribed to the default for its current UID. - - (*) Each user has two quotas against which the keys they own are tracked. One - limits the total number of keys and keyrings, the other limits the total - amount of description and payload space that can be consumed. - - The user can view information on this and other statistics through procfs - files. The root user may also alter the quota limits through sysctl files - (see the section "New procfs files"). - - Process-specific and thread-specific keyrings are not counted towards a - user's quota. - - If a system call that modifies a key or keyring in some way would put the - user over quota, the operation is refused and error EDQUOT is returned. - - (*) There's a system call interface by which userspace programs can create and - manipulate keys and keyrings. - - (*) There's a kernel interface by which services can register types and search - for keys. - - (*) There's a way for the a search done from the kernel to call back to - userspace to request a key that can't be found in a process's keyrings. - - (*) An optional filesystem is available through which the key database can be - viewed and manipulated. - - -====================== -KEY ACCESS PERMISSIONS -====================== - -Keys have an owner user ID, a group access ID, and a permissions mask. The mask -has up to eight bits each for possessor, user, group and other access. Only -six of each set of eight bits are defined. These permissions granted are: - - (*) View - - This permits a key or keyring's attributes to be viewed - including key - type and description. - - (*) Read - - This permits a key's payload to be viewed or a keyring's list of linked - keys. - - (*) Write - - This permits a key's payload to be instantiated or updated, or it allows a - link to be added to or removed from a keyring. - - (*) Search - - This permits keyrings to be searched and keys to be found. Searches can - only recurse into nested keyrings that have search permission set. - - (*) Link - - This permits a key or keyring to be linked to. To create a link from a - keyring to a key, a process must have Write permission on the keyring and - Link permission on the key. - - (*) Set Attribute - - This permits a key's UID, GID and permissions mask to be changed. - -For changing the ownership, group ID or permissions mask, being the owner of -the key or having the sysadmin capability is sufficient. - - -=============== -SELINUX SUPPORT -=============== - -The security class "key" has been added to SELinux so that mandatory access -controls can be applied to keys created within various contexts. This support -is preliminary, and is likely to change quite significantly in the near future. -Currently, all of the basic permissions explained above are provided in SELinux -as well; SELinux is simply invoked after all basic permission checks have been -performed. - -The value of the file /proc/self/attr/keycreate influences the labeling of -newly-created keys. If the contents of that file correspond to an SELinux -security context, then the key will be assigned that context. Otherwise, the -key will be assigned the current context of the task that invoked the key -creation request. Tasks must be granted explicit permission to assign a -particular context to newly-created keys, using the "create" permission in the -key security class. - -The default keyrings associated with users will be labeled with the default -context of the user if and only if the login programs have been instrumented to -properly initialize keycreate during the login process. Otherwise, they will -be labeled with the context of the login program itself. - -Note, however, that the default keyrings associated with the root user are -labeled with the default kernel context, since they are created early in the -boot process, before root has a chance to log in. - -The keyrings associated with new threads are each labeled with the context of -their associated thread, and both session and process keyrings are handled -similarly. - - -================ -NEW PROCFS FILES -================ - -Two files have been added to procfs by which an administrator can find out -about the status of the key service: - - (*) /proc/keys - - This lists the keys that are currently viewable by the task reading the - file, giving information about their type, description and permissions. - It is not possible to view the payload of the key this way, though some - information about it may be given. - - The only keys included in the list are those that grant View permission to - the reading process whether or not it possesses them. Note that LSM - security checks are still performed, and may further filter out keys that - the current process is not authorised to view. - - The contents of the file look like this: - - SERIAL FLAGS USAGE EXPY PERM UID GID TYPE DESCRIPTION: SUMMARY - 00000001 I----- 39 perm 1f3f0000 0 0 keyring _uid_ses.0: 1/4 - 00000002 I----- 2 perm 1f3f0000 0 0 keyring _uid.0: empty - 00000007 I----- 1 perm 1f3f0000 0 0 keyring _pid.1: empty - 0000018d I----- 1 perm 1f3f0000 0 0 keyring _pid.412: empty - 000004d2 I--Q-- 1 perm 1f3f0000 32 -1 keyring _uid.32: 1/4 - 000004d3 I--Q-- 3 perm 1f3f0000 32 -1 keyring _uid_ses.32: empty - 00000892 I--QU- 1 perm 1f000000 0 0 user metal:copper: 0 - 00000893 I--Q-N 1 35s 1f3f0000 0 0 user metal:silver: 0 - 00000894 I--Q-- 1 10h 003f0000 0 0 user metal:gold: 0 - - The flags are: - - I Instantiated - R Revoked - D Dead - Q Contributes to user's quota - U Under construction by callback to userspace - N Negative key - - This file must be enabled at kernel configuration time as it allows anyone - to list the keys database. - - (*) /proc/key-users - - This file lists the tracking data for each user that has at least one key - on the system. Such data includes quota information and statistics: - - [root@andromeda root]# cat /proc/key-users - 0: 46 45/45 1/100 13/10000 - 29: 2 2/2 2/100 40/10000 - 32: 2 2/2 2/100 40/10000 - 38: 2 2/2 2/100 40/10000 - - The format of each line is - : User ID to which this applies - Structure refcount - / Total number of keys and number instantiated - / Key count quota - / Key size quota - - -Four new sysctl files have been added also for the purpose of controlling the -quota limits on keys: - - (*) /proc/sys/kernel/keys/root_maxkeys - /proc/sys/kernel/keys/root_maxbytes - - These files hold the maximum number of keys that root may have and the - maximum total number of bytes of data that root may have stored in those - keys. - - (*) /proc/sys/kernel/keys/maxkeys - /proc/sys/kernel/keys/maxbytes - - These files hold the maximum number of keys that each non-root user may - have and the maximum total number of bytes of data that each of those - users may have stored in their keys. - -Root may alter these by writing each new limit as a decimal number string to -the appropriate file. - - -=============================== -USERSPACE SYSTEM CALL INTERFACE -=============================== - -Userspace can manipulate keys directly through three new syscalls: add_key, -request_key and keyctl. The latter provides a number of functions for -manipulating keys. - -When referring to a key directly, userspace programs should use the key's -serial number (a positive 32-bit integer). However, there are some special -values available for referring to special keys and keyrings that relate to the -process making the call: - - CONSTANT VALUE KEY REFERENCED - ============================== ====== =========================== - KEY_SPEC_THREAD_KEYRING -1 thread-specific keyring - KEY_SPEC_PROCESS_KEYRING -2 process-specific keyring - KEY_SPEC_SESSION_KEYRING -3 session-specific keyring - KEY_SPEC_USER_KEYRING -4 UID-specific keyring - KEY_SPEC_USER_SESSION_KEYRING -5 UID-session keyring - KEY_SPEC_GROUP_KEYRING -6 GID-specific keyring - KEY_SPEC_REQKEY_AUTH_KEY -7 assumed request_key() - authorisation key - - -The main syscalls are: - - (*) Create a new key of given type, description and payload and add it to the - nominated keyring: - - key_serial_t add_key(const char *type, const char *desc, - const void *payload, size_t plen, - key_serial_t keyring); - - If a key of the same type and description as that proposed already exists - in the keyring, this will try to update it with the given payload, or it - will return error EEXIST if that function is not supported by the key - type. The process must also have permission to write to the key to be able - to update it. The new key will have all user permissions granted and no - group or third party permissions. - - Otherwise, this will attempt to create a new key of the specified type and - description, and to instantiate it with the supplied payload and attach it - to the keyring. In this case, an error will be generated if the process - does not have permission to write to the keyring. - - The payload is optional, and the pointer can be NULL if not required by - the type. The payload is plen in size, and plen can be zero for an empty - payload. - - A new keyring can be generated by setting type "keyring", the keyring name - as the description (or NULL) and setting the payload to NULL. - - User defined keys can be created by specifying type "user". It is - recommended that a user defined key's description by prefixed with a type - ID and a colon, such as "krb5tgt:" for a Kerberos 5 ticket granting - ticket. - - Any other type must have been registered with the kernel in advance by a - kernel service such as a filesystem. - - The ID of the new or updated key is returned if successful. - - - (*) Search the process's keyrings for a key, potentially calling out to - userspace to create it. - - key_serial_t request_key(const char *type, const char *description, - const char *callout_info, - key_serial_t dest_keyring); - - This function searches all the process's keyrings in the order thread, - process, session for a matching key. This works very much like - KEYCTL_SEARCH, including the optional attachment of the discovered key to - a keyring. - - If a key cannot be found, and if callout_info is not NULL, then - /sbin/request-key will be invoked in an attempt to obtain a key. The - callout_info string will be passed as an argument to the program. - - See also Documentation/keys-request-key.txt. - - -The keyctl syscall functions are: - - (*) Map a special key ID to a real key ID for this process: - - key_serial_t keyctl(KEYCTL_GET_KEYRING_ID, key_serial_t id, - int create); - - The special key specified by "id" is looked up (with the key being created - if necessary) and the ID of the key or keyring thus found is returned if - it exists. - - If the key does not yet exist, the key will be created if "create" is - non-zero; and the error ENOKEY will be returned if "create" is zero. - - - (*) Replace the session keyring this process subscribes to with a new one: - - key_serial_t keyctl(KEYCTL_JOIN_SESSION_KEYRING, const char *name); - - If name is NULL, an anonymous keyring is created attached to the process - as its session keyring, displacing the old session keyring. - - If name is not NULL, if a keyring of that name exists, the process - attempts to attach it as the session keyring, returning an error if that - is not permitted; otherwise a new keyring of that name is created and - attached as the session keyring. - - To attach to a named keyring, the keyring must have search permission for - the process's ownership. - - The ID of the new session keyring is returned if successful. - - - (*) Update the specified key: - - long keyctl(KEYCTL_UPDATE, key_serial_t key, const void *payload, - size_t plen); - - This will try to update the specified key with the given payload, or it - will return error EOPNOTSUPP if that function is not supported by the key - type. The process must also have permission to write to the key to be able - to update it. - - The payload is of length plen, and may be absent or empty as for - add_key(). - - - (*) Revoke a key: - - long keyctl(KEYCTL_REVOKE, key_serial_t key); - - This makes a key unavailable for further operations. Further attempts to - use the key will be met with error EKEYREVOKED, and the key will no longer - be findable. - - - (*) Change the ownership of a key: - - long keyctl(KEYCTL_CHOWN, key_serial_t key, uid_t uid, gid_t gid); - - This function permits a key's owner and group ID to be changed. Either one - of uid or gid can be set to -1 to suppress that change. - - Only the superuser can change a key's owner to something other than the - key's current owner. Similarly, only the superuser can change a key's - group ID to something other than the calling process's group ID or one of - its group list members. - - - (*) Change the permissions mask on a key: - - long keyctl(KEYCTL_SETPERM, key_serial_t key, key_perm_t perm); - - This function permits the owner of a key or the superuser to change the - permissions mask on a key. - - Only bits the available bits are permitted; if any other bits are set, - error EINVAL will be returned. - - - (*) Describe a key: - - long keyctl(KEYCTL_DESCRIBE, key_serial_t key, char *buffer, - size_t buflen); - - This function returns a summary of the key's attributes (but not its - payload data) as a string in the buffer provided. - - Unless there's an error, it always returns the amount of data it could - produce, even if that's too big for the buffer, but it won't copy more - than requested to userspace. If the buffer pointer is NULL then no copy - will take place. - - A process must have view permission on the key for this function to be - successful. - - If successful, a string is placed in the buffer in the following format: - - ;;;; - - Where type and description are strings, uid and gid are decimal, and perm - is hexadecimal. A NUL character is included at the end of the string if - the buffer is sufficiently big. - - This can be parsed with - - sscanf(buffer, "%[^;];%d;%d;%o;%s", type, &uid, &gid, &mode, desc); - - - (*) Clear out a keyring: - - long keyctl(KEYCTL_CLEAR, key_serial_t keyring); - - This function clears the list of keys attached to a keyring. The calling - process must have write permission on the keyring, and it must be a - keyring (or else error ENOTDIR will result). - - - (*) Link a key into a keyring: - - long keyctl(KEYCTL_LINK, key_serial_t keyring, key_serial_t key); - - This function creates a link from the keyring to the key. The process must - have write permission on the keyring and must have link permission on the - key. - - Should the keyring not be a keyring, error ENOTDIR will result; and if the - keyring is full, error ENFILE will result. - - The link procedure checks the nesting of the keyrings, returning ELOOP if - it appears too deep or EDEADLK if the link would introduce a cycle. - - Any links within the keyring to keys that match the new key in terms of - type and description will be discarded from the keyring as the new one is - added. - - - (*) Unlink a key or keyring from another keyring: - - long keyctl(KEYCTL_UNLINK, key_serial_t keyring, key_serial_t key); - - This function looks through the keyring for the first link to the - specified key, and removes it if found. Subsequent links to that key are - ignored. The process must have write permission on the keyring. - - If the keyring is not a keyring, error ENOTDIR will result; and if the key - is not present, error ENOENT will be the result. - - - (*) Search a keyring tree for a key: - - key_serial_t keyctl(KEYCTL_SEARCH, key_serial_t keyring, - const char *type, const char *description, - key_serial_t dest_keyring); - - This searches the keyring tree headed by the specified keyring until a key - is found that matches the type and description criteria. Each keyring is - checked for keys before recursion into its children occurs. - - The process must have search permission on the top level keyring, or else - error EACCES will result. Only keyrings that the process has search - permission on will be recursed into, and only keys and keyrings for which - a process has search permission can be matched. If the specified keyring - is not a keyring, ENOTDIR will result. - - If the search succeeds, the function will attempt to link the found key - into the destination keyring if one is supplied (non-zero ID). All the - constraints applicable to KEYCTL_LINK apply in this case too. - - Error ENOKEY, EKEYREVOKED or EKEYEXPIRED will be returned if the search - fails. On success, the resulting key ID will be returned. - - - (*) Read the payload data from a key: - - long keyctl(KEYCTL_READ, key_serial_t keyring, char *buffer, - size_t buflen); - - This function attempts to read the payload data from the specified key - into the buffer. The process must have read permission on the key to - succeed. - - The returned data will be processed for presentation by the key type. For - instance, a keyring will return an array of key_serial_t entries - representing the IDs of all the keys to which it is subscribed. The user - defined key type will return its data as is. If a key type does not - implement this function, error EOPNOTSUPP will result. - - As much of the data as can be fitted into the buffer will be copied to - userspace if the buffer pointer is not NULL. - - On a successful return, the function will always return the amount of data - available rather than the amount copied. - - - (*) Instantiate a partially constructed key. - - long keyctl(KEYCTL_INSTANTIATE, key_serial_t key, - const void *payload, size_t plen, - key_serial_t keyring); - long keyctl(KEYCTL_INSTANTIATE_IOV, key_serial_t key, - const struct iovec *payload_iov, unsigned ioc, - key_serial_t keyring); - - If the kernel calls back to userspace to complete the instantiation of a - key, userspace should use this call to supply data for the key before the - invoked process returns, or else the key will be marked negative - automatically. - - The process must have write access on the key to be able to instantiate - it, and the key must be uninstantiated. - - If a keyring is specified (non-zero), the key will also be linked into - that keyring, however all the constraints applying in KEYCTL_LINK apply in - this case too. - - The payload and plen arguments describe the payload data as for add_key(). - - The payload_iov and ioc arguments describe the payload data in an iovec - array instead of a single buffer. - - - (*) Negatively instantiate a partially constructed key. - - long keyctl(KEYCTL_NEGATE, key_serial_t key, - unsigned timeout, key_serial_t keyring); - long keyctl(KEYCTL_REJECT, key_serial_t key, - unsigned timeout, unsigned error, key_serial_t keyring); - - If the kernel calls back to userspace to complete the instantiation of a - key, userspace should use this call mark the key as negative before the - invoked process returns if it is unable to fulfil the request. - - The process must have write access on the key to be able to instantiate - it, and the key must be uninstantiated. - - If a keyring is specified (non-zero), the key will also be linked into - that keyring, however all the constraints applying in KEYCTL_LINK apply in - this case too. - - If the key is rejected, future searches for it will return the specified - error code until the rejected key expires. Negating the key is the same - as rejecting the key with ENOKEY as the error code. - - - (*) Set the default request-key destination keyring. - - long keyctl(KEYCTL_SET_REQKEY_KEYRING, int reqkey_defl); - - This sets the default keyring to which implicitly requested keys will be - attached for this thread. reqkey_defl should be one of these constants: - - CONSTANT VALUE NEW DEFAULT KEYRING - ====================================== ====== ======================= - KEY_REQKEY_DEFL_NO_CHANGE -1 No change - KEY_REQKEY_DEFL_DEFAULT 0 Default[1] - KEY_REQKEY_DEFL_THREAD_KEYRING 1 Thread keyring - KEY_REQKEY_DEFL_PROCESS_KEYRING 2 Process keyring - KEY_REQKEY_DEFL_SESSION_KEYRING 3 Session keyring - KEY_REQKEY_DEFL_USER_KEYRING 4 User keyring - KEY_REQKEY_DEFL_USER_SESSION_KEYRING 5 User session keyring - KEY_REQKEY_DEFL_GROUP_KEYRING 6 Group keyring - - The old default will be returned if successful and error EINVAL will be - returned if reqkey_defl is not one of the above values. - - The default keyring can be overridden by the keyring indicated to the - request_key() system call. - - Note that this setting is inherited across fork/exec. - - [1] The default is: the thread keyring if there is one, otherwise - the process keyring if there is one, otherwise the session keyring if - there is one, otherwise the user default session keyring. - - - (*) Set the timeout on a key. - - long keyctl(KEYCTL_SET_TIMEOUT, key_serial_t key, unsigned timeout); - - This sets or clears the timeout on a key. The timeout can be 0 to clear - the timeout or a number of seconds to set the expiry time that far into - the future. - - The process must have attribute modification access on a key to set its - timeout. Timeouts may not be set with this function on negative, revoked - or expired keys. - - - (*) Assume the authority granted to instantiate a key - - long keyctl(KEYCTL_ASSUME_AUTHORITY, key_serial_t key); - - This assumes or divests the authority required to instantiate the - specified key. Authority can only be assumed if the thread has the - authorisation key associated with the specified key in its keyrings - somewhere. - - Once authority is assumed, searches for keys will also search the - requester's keyrings using the requester's security label, UID, GID and - groups. - - If the requested authority is unavailable, error EPERM will be returned, - likewise if the authority has been revoked because the target key is - already instantiated. - - If the specified key is 0, then any assumed authority will be divested. - - The assumed authoritative key is inherited across fork and exec. - - - (*) Get the LSM security context attached to a key. - - long keyctl(KEYCTL_GET_SECURITY, key_serial_t key, char *buffer, - size_t buflen) - - This function returns a string that represents the LSM security context - attached to a key in the buffer provided. - - Unless there's an error, it always returns the amount of data it could - produce, even if that's too big for the buffer, but it won't copy more - than requested to userspace. If the buffer pointer is NULL then no copy - will take place. - - A NUL character is included at the end of the string if the buffer is - sufficiently big. This is included in the returned count. If no LSM is - in force then an empty string will be returned. - - A process must have view permission on the key for this function to be - successful. - - - (*) Install the calling process's session keyring on its parent. - - long keyctl(KEYCTL_SESSION_TO_PARENT); - - This functions attempts to install the calling process's session keyring - on to the calling process's parent, replacing the parent's current session - keyring. - - The calling process must have the same ownership as its parent, the - keyring must have the same ownership as the calling process, the calling - process must have LINK permission on the keyring and the active LSM module - mustn't deny permission, otherwise error EPERM will be returned. - - Error ENOMEM will be returned if there was insufficient memory to complete - the operation, otherwise 0 will be returned to indicate success. - - The keyring will be replaced next time the parent process leaves the - kernel and resumes executing userspace. - - -=============== -KERNEL SERVICES -=============== - -The kernel services for key management are fairly simple to deal with. They can -be broken down into two areas: keys and key types. - -Dealing with keys is fairly straightforward. Firstly, the kernel service -registers its type, then it searches for a key of that type. It should retain -the key as long as it has need of it, and then it should release it. For a -filesystem or device file, a search would probably be performed during the open -call, and the key released upon close. How to deal with conflicting keys due to -two different users opening the same file is left to the filesystem author to -solve. - -To access the key manager, the following header must be #included: - - - -Specific key types should have a header file under include/keys/ that should be -used to access that type. For keys of type "user", for example, that would be: - - - -Note that there are two different types of pointers to keys that may be -encountered: - - (*) struct key * - - This simply points to the key structure itself. Key structures will be at - least four-byte aligned. - - (*) key_ref_t - - This is equivalent to a struct key *, but the least significant bit is set - if the caller "possesses" the key. By "possession" it is meant that the - calling processes has a searchable link to the key from one of its - keyrings. There are three functions for dealing with these: - - key_ref_t make_key_ref(const struct key *key, - unsigned long possession); - - struct key *key_ref_to_ptr(const key_ref_t key_ref); - - unsigned long is_key_possessed(const key_ref_t key_ref); - - The first function constructs a key reference from a key pointer and - possession information (which must be 0 or 1 and not any other value). - - The second function retrieves the key pointer from a reference and the - third retrieves the possession flag. - -When accessing a key's payload contents, certain precautions must be taken to -prevent access vs modification races. See the section "Notes on accessing -payload contents" for more information. - -(*) To search for a key, call: - - struct key *request_key(const struct key_type *type, - const char *description, - const char *callout_info); - - This is used to request a key or keyring with a description that matches - the description specified according to the key type's match function. This - permits approximate matching to occur. If callout_string is not NULL, then - /sbin/request-key will be invoked in an attempt to obtain the key from - userspace. In that case, callout_string will be passed as an argument to - the program. - - Should the function fail error ENOKEY, EKEYEXPIRED or EKEYREVOKED will be - returned. - - If successful, the key will have been attached to the default keyring for - implicitly obtained request-key keys, as set by KEYCTL_SET_REQKEY_KEYRING. - - See also Documentation/keys-request-key.txt. - - -(*) To search for a key, passing auxiliary data to the upcaller, call: - - struct key *request_key_with_auxdata(const struct key_type *type, - const char *description, - const void *callout_info, - size_t callout_len, - void *aux); - - This is identical to request_key(), except that the auxiliary data is - passed to the key_type->request_key() op if it exists, and the callout_info - is a blob of length callout_len, if given (the length may be 0). - - -(*) A key can be requested asynchronously by calling one of: - - struct key *request_key_async(const struct key_type *type, - const char *description, - const void *callout_info, - size_t callout_len); - - or: - - struct key *request_key_async_with_auxdata(const struct key_type *type, - const char *description, - const char *callout_info, - size_t callout_len, - void *aux); - - which are asynchronous equivalents of request_key() and - request_key_with_auxdata() respectively. - - These two functions return with the key potentially still under - construction. To wait for construction completion, the following should be - called: - - int wait_for_key_construction(struct key *key, bool intr); - - The function will wait for the key to finish being constructed and then - invokes key_validate() to return an appropriate value to indicate the state - of the key (0 indicates the key is usable). - - If intr is true, then the wait can be interrupted by a signal, in which - case error ERESTARTSYS will be returned. - - -(*) When it is no longer required, the key should be released using: - - void key_put(struct key *key); - - Or: - - void key_ref_put(key_ref_t key_ref); - - These can be called from interrupt context. If CONFIG_KEYS is not set then - the argument will not be parsed. - - -(*) Extra references can be made to a key by calling the following function: - - struct key *key_get(struct key *key); - - These need to be disposed of by calling key_put() when they've been - finished with. The key pointer passed in will be returned. If the pointer - is NULL or CONFIG_KEYS is not set then the key will not be dereferenced and - no increment will take place. - - -(*) A key's serial number can be obtained by calling: - - key_serial_t key_serial(struct key *key); - - If key is NULL or if CONFIG_KEYS is not set then 0 will be returned (in the - latter case without parsing the argument). - - -(*) If a keyring was found in the search, this can be further searched by: - - key_ref_t keyring_search(key_ref_t keyring_ref, - const struct key_type *type, - const char *description) - - This searches the keyring tree specified for a matching key. Error ENOKEY - is returned upon failure (use IS_ERR/PTR_ERR to determine). If successful, - the returned key will need to be released. - - The possession attribute from the keyring reference is used to control - access through the permissions mask and is propagated to the returned key - reference pointer if successful. - - -(*) To check the validity of a key, this function can be called: - - int validate_key(struct key *key); - - This checks that the key in question hasn't expired or and hasn't been - revoked. Should the key be invalid, error EKEYEXPIRED or EKEYREVOKED will - be returned. If the key is NULL or if CONFIG_KEYS is not set then 0 will be - returned (in the latter case without parsing the argument). - - -(*) To register a key type, the following function should be called: - - int register_key_type(struct key_type *type); - - This will return error EEXIST if a type of the same name is already - present. - - -(*) To unregister a key type, call: - - void unregister_key_type(struct key_type *type); - - -Under some circumstances, it may be desirable to deal with a bundle of keys. -The facility provides access to the keyring type for managing such a bundle: - - struct key_type key_type_keyring; - -This can be used with a function such as request_key() to find a specific -keyring in a process's keyrings. A keyring thus found can then be searched -with keyring_search(). Note that it is not possible to use request_key() to -search a specific keyring, so using keyrings in this way is of limited utility. - - -=================================== -NOTES ON ACCESSING PAYLOAD CONTENTS -=================================== - -The simplest payload is just a number in key->payload.value. In this case, -there's no need to indulge in RCU or locking when accessing the payload. - -More complex payload contents must be allocated and a pointer to them set in -key->payload.data. One of the following ways must be selected to access the -data: - - (1) Unmodifiable key type. - - If the key type does not have a modify method, then the key's payload can - be accessed without any form of locking, provided that it's known to be - instantiated (uninstantiated keys cannot be "found"). - - (2) The key's semaphore. - - The semaphore could be used to govern access to the payload and to control - the payload pointer. It must be write-locked for modifications and would - have to be read-locked for general access. The disadvantage of doing this - is that the accessor may be required to sleep. - - (3) RCU. - - RCU must be used when the semaphore isn't already held; if the semaphore - is held then the contents can't change under you unexpectedly as the - semaphore must still be used to serialise modifications to the key. The - key management code takes care of this for the key type. - - However, this means using: - - rcu_read_lock() ... rcu_dereference() ... rcu_read_unlock() - - to read the pointer, and: - - rcu_dereference() ... rcu_assign_pointer() ... call_rcu() - - to set the pointer and dispose of the old contents after a grace period. - Note that only the key type should ever modify a key's payload. - - Furthermore, an RCU controlled payload must hold a struct rcu_head for the - use of call_rcu() and, if the payload is of variable size, the length of - the payload. key->datalen cannot be relied upon to be consistent with the - payload just dereferenced if the key's semaphore is not held. - - -=================== -DEFINING A KEY TYPE -=================== - -A kernel service may want to define its own key type. For instance, an AFS -filesystem might want to define a Kerberos 5 ticket key type. To do this, it -author fills in a key_type struct and registers it with the system. - -Source files that implement key types should include the following header file: - - - -The structure has a number of fields, some of which are mandatory: - - (*) const char *name - - The name of the key type. This is used to translate a key type name - supplied by userspace into a pointer to the structure. - - - (*) size_t def_datalen - - This is optional - it supplies the default payload data length as - contributed to the quota. If the key type's payload is always or almost - always the same size, then this is a more efficient way to do things. - - The data length (and quota) on a particular key can always be changed - during instantiation or update by calling: - - int key_payload_reserve(struct key *key, size_t datalen); - - With the revised data length. Error EDQUOT will be returned if this is not - viable. - - - (*) int (*vet_description)(const char *description); - - This optional method is called to vet a key description. If the key type - doesn't approve of the key description, it may return an error, otherwise - it should return 0. - - - (*) int (*instantiate)(struct key *key, const void *data, size_t datalen); - - This method is called to attach a payload to a key during construction. - The payload attached need not bear any relation to the data passed to this - function. - - If the amount of data attached to the key differs from the size in - keytype->def_datalen, then key_payload_reserve() should be called. - - This method does not have to lock the key in order to attach a payload. - The fact that KEY_FLAG_INSTANTIATED is not set in key->flags prevents - anything else from gaining access to the key. - - It is safe to sleep in this method. - - - (*) int (*update)(struct key *key, const void *data, size_t datalen); - - If this type of key can be updated, then this method should be provided. - It is called to update a key's payload from the blob of data provided. - - key_payload_reserve() should be called if the data length might change - before any changes are actually made. Note that if this succeeds, the type - is committed to changing the key because it's already been altered, so all - memory allocation must be done first. - - The key will have its semaphore write-locked before this method is called, - but this only deters other writers; any changes to the key's payload must - be made under RCU conditions, and call_rcu() must be used to dispose of - the old payload. - - key_payload_reserve() should be called before the changes are made, but - after all allocations and other potentially failing function calls are - made. - - It is safe to sleep in this method. - - - (*) int (*match)(const struct key *key, const void *desc); - - This method is called to match a key against a description. It should - return non-zero if the two match, zero if they don't. - - This method should not need to lock the key in any way. The type and - description can be considered invariant, and the payload should not be - accessed (the key may not yet be instantiated). - - It is not safe to sleep in this method; the caller may hold spinlocks. - - - (*) void (*revoke)(struct key *key); - - This method is optional. It is called to discard part of the payload - data upon a key being revoked. The caller will have the key semaphore - write-locked. - - It is safe to sleep in this method, though care should be taken to avoid - a deadlock against the key semaphore. - - - (*) void (*destroy)(struct key *key); - - This method is optional. It is called to discard the payload data on a key - when it is being destroyed. - - This method does not need to lock the key to access the payload; it can - consider the key as being inaccessible at this time. Note that the key's - type may have been changed before this function is called. - - It is not safe to sleep in this method; the caller may hold spinlocks. - - - (*) void (*describe)(const struct key *key, struct seq_file *p); - - This method is optional. It is called during /proc/keys reading to - summarise a key's description and payload in text form. - - This method will be called with the RCU read lock held. rcu_dereference() - should be used to read the payload pointer if the payload is to be - accessed. key->datalen cannot be trusted to stay consistent with the - contents of the payload. - - The description will not change, though the key's state may. - - It is not safe to sleep in this method; the RCU read lock is held by the - caller. - - - (*) long (*read)(const struct key *key, char __user *buffer, size_t buflen); - - This method is optional. It is called by KEYCTL_READ to translate the - key's payload into something a blob of data for userspace to deal with. - Ideally, the blob should be in the same format as that passed in to the - instantiate and update methods. - - If successful, the blob size that could be produced should be returned - rather than the size copied. - - This method will be called with the key's semaphore read-locked. This will - prevent the key's payload changing. It is not necessary to use RCU locking - when accessing the key's payload. It is safe to sleep in this method, such - as might happen when the userspace buffer is accessed. - - - (*) int (*request_key)(struct key_construction *cons, const char *op, - void *aux); - - This method is optional. If provided, request_key() and friends will - invoke this function rather than upcalling to /sbin/request-key to operate - upon a key of this type. - - The aux parameter is as passed to request_key_async_with_auxdata() and - similar or is NULL otherwise. Also passed are the construction record for - the key to be operated upon and the operation type (currently only - "create"). - - This method is permitted to return before the upcall is complete, but the - following function must be called under all circumstances to complete the - instantiation process, whether or not it succeeds, whether or not there's - an error: - - void complete_request_key(struct key_construction *cons, int error); - - The error parameter should be 0 on success, -ve on error. The - construction record is destroyed by this action and the authorisation key - will be revoked. If an error is indicated, the key under construction - will be negatively instantiated if it wasn't already instantiated. - - If this method returns an error, that error will be returned to the - caller of request_key*(). complete_request_key() must be called prior to - returning. - - The key under construction and the authorisation key can be found in the - key_construction struct pointed to by cons: - - (*) struct key *key; - - The key under construction. - - (*) struct key *authkey; - - The authorisation key. - - -============================ -REQUEST-KEY CALLBACK SERVICE -============================ - -To create a new key, the kernel will attempt to execute the following command -line: - - /sbin/request-key create \ - - - is the key being constructed, and the three keyrings are the process -keyrings from the process that caused the search to be issued. These are -included for two reasons: - - (1) There may be an authentication token in one of the keyrings that is - required to obtain the key, eg: a Kerberos Ticket-Granting Ticket. - - (2) The new key should probably be cached in one of these rings. - -This program should set it UID and GID to those specified before attempting to -access any more keys. It may then look around for a user specific process to -hand the request off to (perhaps a path held in placed in another key by, for -example, the KDE desktop manager). - -The program (or whatever it calls) should finish construction of the key by -calling KEYCTL_INSTANTIATE or KEYCTL_INSTANTIATE_IOV, which also permits it to -cache the key in one of the keyrings (probably the session ring) before -returning. Alternatively, the key can be marked as negative with KEYCTL_NEGATE -or KEYCTL_REJECT; this also permits the key to be cached in one of the -keyrings. - -If it returns with the key remaining in the unconstructed state, the key will -be marked as being negative, it will be added to the session keyring, and an -error will be returned to the key requestor. - -Supplementary information may be provided from whoever or whatever invoked this -service. This will be passed as the parameter. If no such -information was made available, then "-" will be passed as this parameter -instead. - - -Similarly, the kernel may attempt to update an expired or a soon to expire key -by executing: - - /sbin/request-key update \ - - -In this case, the program isn't required to actually attach the key to a ring; -the rings are provided for reference. - - -================== -GARBAGE COLLECTION -================== - -Dead keys (for which the type has been removed) will be automatically unlinked -from those keyrings that point to them and deleted as soon as possible by a -background garbage collector. - -Similarly, revoked and expired keys will be garbage collected, but only after a -certain amount of time has passed. This time is set as a number of seconds in: - - /proc/sys/kernel/keys/gc_delay diff --git a/Documentation/networking/dns_resolver.txt b/Documentation/networking/dns_resolver.txt index 04ca06325b08..7f531ad83285 100644 --- a/Documentation/networking/dns_resolver.txt +++ b/Documentation/networking/dns_resolver.txt @@ -139,8 +139,8 @@ the key will be discarded and recreated when the data it holds has expired. dns_query() returns a copy of the value attached to the key, or an error if that is indicated instead. -See for further information about -request-key function. +See for further +information about request-key function. ========= diff --git a/Documentation/security/00-INDEX b/Documentation/security/00-INDEX new file mode 100644 index 000000000000..19bc49439cac --- /dev/null +++ b/Documentation/security/00-INDEX @@ -0,0 +1,18 @@ +00-INDEX + - this file. +SELinux.txt + - how to get started with the SELinux security enhancement. +Smack.txt + - documentation on the Smack Linux Security Module. +apparmor.txt + - documentation on the AppArmor security extension. +credentials.txt + - documentation about credentials in Linux. +keys-request-key.txt + - description of the kernel key request service. +keys-trusted-encrypted.txt + - info on the Trusted and Encrypted keys in the kernel key ring service. +keys.txt + - description of the kernel key retention service. +tomoyo.txt + - documentation on the TOMOYO Linux Security Module. diff --git a/Documentation/security/SELinux.txt b/Documentation/security/SELinux.txt new file mode 100644 index 000000000000..07eae00f3314 --- /dev/null +++ b/Documentation/security/SELinux.txt @@ -0,0 +1,27 @@ +If you want to use SELinux, chances are you will want +to use the distro-provided policies, or install the +latest reference policy release from + http://oss.tresys.com/projects/refpolicy + +However, if you want to install a dummy policy for +testing, you can do using 'mdp' provided under +scripts/selinux. Note that this requires the selinux +userspace to be installed - in particular you will +need checkpolicy to compile a kernel, and setfiles and +fixfiles to label the filesystem. + + 1. Compile the kernel with selinux enabled. + 2. Type 'make' to compile mdp. + 3. Make sure that you are not running with + SELinux enabled and a real policy. If + you are, reboot with selinux disabled + before continuing. + 4. Run install_policy.sh: + cd scripts/selinux + sh install_policy.sh + +Step 4 will create a new dummy policy valid for your +kernel, with a single selinux user, role, and type. +It will compile the policy, will set your SELINUXTYPE to +dummy in /etc/selinux/config, install the compiled policy +as 'dummy', and relabel your filesystem. diff --git a/Documentation/security/Smack.txt b/Documentation/security/Smack.txt new file mode 100644 index 000000000000..e9dab41c0fe0 --- /dev/null +++ b/Documentation/security/Smack.txt @@ -0,0 +1,541 @@ + + + "Good for you, you've decided to clean the elevator!" + - The Elevator, from Dark Star + +Smack is the the Simplified Mandatory Access Control Kernel. +Smack is a kernel based implementation of mandatory access +control that includes simplicity in its primary design goals. + +Smack is not the only Mandatory Access Control scheme +available for Linux. Those new to Mandatory Access Control +are encouraged to compare Smack with the other mechanisms +available to determine which is best suited to the problem +at hand. + +Smack consists of three major components: + - The kernel + - A start-up script and a few modified applications + - Configuration data + +The kernel component of Smack is implemented as a Linux +Security Modules (LSM) module. It requires netlabel and +works best with file systems that support extended attributes, +although xattr support is not strictly required. +It is safe to run a Smack kernel under a "vanilla" distribution. +Smack kernels use the CIPSO IP option. Some network +configurations are intolerant of IP options and can impede +access to systems that use them as Smack does. + +The startup script etc-init.d-smack should be installed +in /etc/init.d/smack and should be invoked early in the +start-up process. On Fedora rc5.d/S02smack is recommended. +This script ensures that certain devices have the correct +Smack attributes and loads the Smack configuration if +any is defined. This script invokes two programs that +ensure configuration data is properly formatted. These +programs are /usr/sbin/smackload and /usr/sin/smackcipso. +The system will run just fine without these programs, +but it will be difficult to set access rules properly. + +A version of "ls" that provides a "-M" option to display +Smack labels on long listing is available. + +A hacked version of sshd that allows network logins by users +with specific Smack labels is available. This version does +not work for scp. You must set the /etc/ssh/sshd_config +line: + UsePrivilegeSeparation no + +The format of /etc/smack/usr is: + + username smack + +In keeping with the intent of Smack, configuration data is +minimal and not strictly required. The most important +configuration step is mounting the smackfs pseudo filesystem. + +Add this line to /etc/fstab: + + smackfs /smack smackfs smackfsdef=* 0 0 + +and create the /smack directory for mounting. + +Smack uses extended attributes (xattrs) to store file labels. +The command to set a Smack label on a file is: + + # attr -S -s SMACK64 -V "value" path + +NOTE: Smack labels are limited to 23 characters. The attr command + does not enforce this restriction and can be used to set + invalid Smack labels on files. + +If you don't do anything special all users will get the floor ("_") +label when they log in. If you do want to log in via the hacked ssh +at other labels use the attr command to set the smack value on the +home directory and its contents. + +You can add access rules in /etc/smack/accesses. They take the form: + + subjectlabel objectlabel access + +access is a combination of the letters rwxa which specify the +kind of access permitted a subject with subjectlabel on an +object with objectlabel. If there is no rule no access is allowed. + +A process can see the smack label it is running with by +reading /proc/self/attr/current. A privileged process can +set the process smack by writing there. + +Look for additional programs on http://schaufler-ca.com + +From the Smack Whitepaper: + +The Simplified Mandatory Access Control Kernel + +Casey Schaufler +casey@schaufler-ca.com + +Mandatory Access Control + +Computer systems employ a variety of schemes to constrain how information is +shared among the people and services using the machine. Some of these schemes +allow the program or user to decide what other programs or users are allowed +access to pieces of data. These schemes are called discretionary access +control mechanisms because the access control is specified at the discretion +of the user. Other schemes do not leave the decision regarding what a user or +program can access up to users or programs. These schemes are called mandatory +access control mechanisms because you don't have a choice regarding the users +or programs that have access to pieces of data. + +Bell & LaPadula + +From the middle of the 1980's until the turn of the century Mandatory Access +Control (MAC) was very closely associated with the Bell & LaPadula security +model, a mathematical description of the United States Department of Defense +policy for marking paper documents. MAC in this form enjoyed a following +within the Capital Beltway and Scandinavian supercomputer centers but was +often sited as failing to address general needs. + +Domain Type Enforcement + +Around the turn of the century Domain Type Enforcement (DTE) became popular. +This scheme organizes users, programs, and data into domains that are +protected from each other. This scheme has been widely deployed as a component +of popular Linux distributions. The administrative overhead required to +maintain this scheme and the detailed understanding of the whole system +necessary to provide a secure domain mapping leads to the scheme being +disabled or used in limited ways in the majority of cases. + +Smack + +Smack is a Mandatory Access Control mechanism designed to provide useful MAC +while avoiding the pitfalls of its predecessors. The limitations of Bell & +LaPadula are addressed by providing a scheme whereby access can be controlled +according to the requirements of the system and its purpose rather than those +imposed by an arcane government policy. The complexity of Domain Type +Enforcement and avoided by defining access controls in terms of the access +modes already in use. + +Smack Terminology + +The jargon used to talk about Smack will be familiar to those who have dealt +with other MAC systems and shouldn't be too difficult for the uninitiated to +pick up. There are four terms that are used in a specific way and that are +especially important: + + Subject: A subject is an active entity on the computer system. + On Smack a subject is a task, which is in turn the basic unit + of execution. + + Object: An object is a passive entity on the computer system. + On Smack files of all types, IPC, and tasks can be objects. + + Access: Any attempt by a subject to put information into or get + information from an object is an access. + + Label: Data that identifies the Mandatory Access Control + characteristics of a subject or an object. + +These definitions are consistent with the traditional use in the security +community. There are also some terms from Linux that are likely to crop up: + + Capability: A task that possesses a capability has permission to + violate an aspect of the system security policy, as identified by + the specific capability. A task that possesses one or more + capabilities is a privileged task, whereas a task with no + capabilities is an unprivileged task. + + Privilege: A task that is allowed to violate the system security + policy is said to have privilege. As of this writing a task can + have privilege either by possessing capabilities or by having an + effective user of root. + +Smack Basics + +Smack is an extension to a Linux system. It enforces additional restrictions +on what subjects can access which objects, based on the labels attached to +each of the subject and the object. + +Labels + +Smack labels are ASCII character strings, one to twenty-three characters in +length. Single character labels using special characters, that being anything +other than a letter or digit, are reserved for use by the Smack development +team. Smack labels are unstructured, case sensitive, and the only operation +ever performed on them is comparison for equality. Smack labels cannot +contain unprintable characters, the "/" (slash), the "\" (backslash), the "'" +(quote) and '"' (double-quote) characters. +Smack labels cannot begin with a '-', which is reserved for special options. + +There are some predefined labels: + + _ Pronounced "floor", a single underscore character. + ^ Pronounced "hat", a single circumflex character. + * Pronounced "star", a single asterisk character. + ? Pronounced "huh", a single question mark character. + @ Pronounced "Internet", a single at sign character. + +Every task on a Smack system is assigned a label. System tasks, such as +init(8) and systems daemons, are run with the floor ("_") label. User tasks +are assigned labels according to the specification found in the +/etc/smack/user configuration file. + +Access Rules + +Smack uses the traditional access modes of Linux. These modes are read, +execute, write, and occasionally append. There are a few cases where the +access mode may not be obvious. These include: + + Signals: A signal is a write operation from the subject task to + the object task. + Internet Domain IPC: Transmission of a packet is considered a + write operation from the source task to the destination task. + +Smack restricts access based on the label attached to a subject and the label +attached to the object it is trying to access. The rules enforced are, in +order: + + 1. Any access requested by a task labeled "*" is denied. + 2. A read or execute access requested by a task labeled "^" + is permitted. + 3. A read or execute access requested on an object labeled "_" + is permitted. + 4. Any access requested on an object labeled "*" is permitted. + 5. Any access requested by a task on an object with the same + label is permitted. + 6. Any access requested that is explicitly defined in the loaded + rule set is permitted. + 7. Any other access is denied. + +Smack Access Rules + +With the isolation provided by Smack access separation is simple. There are +many interesting cases where limited access by subjects to objects with +different labels is desired. One example is the familiar spy model of +sensitivity, where a scientist working on a highly classified project would be +able to read documents of lower classifications and anything she writes will +be "born" highly classified. To accommodate such schemes Smack includes a +mechanism for specifying rules allowing access between labels. + +Access Rule Format + +The format of an access rule is: + + subject-label object-label access + +Where subject-label is the Smack label of the task, object-label is the Smack +label of the thing being accessed, and access is a string specifying the sort +of access allowed. The Smack labels are limited to 23 characters. The access +specification is searched for letters that describe access modes: + + a: indicates that append access should be granted. + r: indicates that read access should be granted. + w: indicates that write access should be granted. + x: indicates that execute access should be granted. + +Uppercase values for the specification letters are allowed as well. +Access mode specifications can be in any order. Examples of acceptable rules +are: + + TopSecret Secret rx + Secret Unclass R + Manager Game x + User HR w + New Old rRrRr + Closed Off - + +Examples of unacceptable rules are: + + Top Secret Secret rx + Ace Ace r + Odd spells waxbeans + +Spaces are not allowed in labels. Since a subject always has access to files +with the same label specifying a rule for that case is pointless. Only +valid letters (rwxaRWXA) and the dash ('-') character are allowed in +access specifications. The dash is a placeholder, so "a-r" is the same +as "ar". A lone dash is used to specify that no access should be allowed. + +Applying Access Rules + +The developers of Linux rarely define new sorts of things, usually importing +schemes and concepts from other systems. Most often, the other systems are +variants of Unix. Unix has many endearing properties, but consistency of +access control models is not one of them. Smack strives to treat accesses as +uniformly as is sensible while keeping with the spirit of the underlying +mechanism. + +File system objects including files, directories, named pipes, symbolic links, +and devices require access permissions that closely match those used by mode +bit access. To open a file for reading read access is required on the file. To +search a directory requires execute access. Creating a file with write access +requires both read and write access on the containing directory. Deleting a +file requires read and write access to the file and to the containing +directory. It is possible that a user may be able to see that a file exists +but not any of its attributes by the circumstance of having read access to the +containing directory but not to the differently labeled file. This is an +artifact of the file name being data in the directory, not a part of the file. + +IPC objects, message queues, semaphore sets, and memory segments exist in flat +namespaces and access requests are only required to match the object in +question. + +Process objects reflect tasks on the system and the Smack label used to access +them is the same Smack label that the task would use for its own access +attempts. Sending a signal via the kill() system call is a write operation +from the signaler to the recipient. Debugging a process requires both reading +and writing. Creating a new task is an internal operation that results in two +tasks with identical Smack labels and requires no access checks. + +Sockets are data structures attached to processes and sending a packet from +one process to another requires that the sender have write access to the +receiver. The receiver is not required to have read access to the sender. + +Setting Access Rules + +The configuration file /etc/smack/accesses contains the rules to be set at +system startup. The contents are written to the special file /smack/load. +Rules can be written to /smack/load at any time and take effect immediately. +For any pair of subject and object labels there can be only one rule, with the +most recently specified overriding any earlier specification. + +The program smackload is provided to ensure data is formatted +properly when written to /smack/load. This program reads lines +of the form + + subjectlabel objectlabel mode. + +Task Attribute + +The Smack label of a process can be read from /proc//attr/current. A +process can read its own Smack label from /proc/self/attr/current. A +privileged process can change its own Smack label by writing to +/proc/self/attr/current but not the label of another process. + +File Attribute + +The Smack label of a filesystem object is stored as an extended attribute +named SMACK64 on the file. This attribute is in the security namespace. It can +only be changed by a process with privilege. + +Privilege + +A process with CAP_MAC_OVERRIDE is privileged. + +Smack Networking + +As mentioned before, Smack enforces access control on network protocol +transmissions. Every packet sent by a Smack process is tagged with its Smack +label. This is done by adding a CIPSO tag to the header of the IP packet. Each +packet received is expected to have a CIPSO tag that identifies the label and +if it lacks such a tag the network ambient label is assumed. Before the packet +is delivered a check is made to determine that a subject with the label on the +packet has write access to the receiving process and if that is not the case +the packet is dropped. + +CIPSO Configuration + +It is normally unnecessary to specify the CIPSO configuration. The default +values used by the system handle all internal cases. Smack will compose CIPSO +label values to match the Smack labels being used without administrative +intervention. Unlabeled packets that come into the system will be given the +ambient label. + +Smack requires configuration in the case where packets from a system that is +not smack that speaks CIPSO may be encountered. Usually this will be a Trusted +Solaris system, but there are other, less widely deployed systems out there. +CIPSO provides 3 important values, a Domain Of Interpretation (DOI), a level, +and a category set with each packet. The DOI is intended to identify a group +of systems that use compatible labeling schemes, and the DOI specified on the +smack system must match that of the remote system or packets will be +discarded. The DOI is 3 by default. The value can be read from /smack/doi and +can be changed by writing to /smack/doi. + +The label and category set are mapped to a Smack label as defined in +/etc/smack/cipso. + +A Smack/CIPSO mapping has the form: + + smack level [category [category]*] + +Smack does not expect the level or category sets to be related in any +particular way and does not assume or assign accesses based on them. Some +examples of mappings: + + TopSecret 7 + TS:A,B 7 1 2 + SecBDE 5 2 4 6 + RAFTERS 7 12 26 + +The ":" and "," characters are permitted in a Smack label but have no special +meaning. + +The mapping of Smack labels to CIPSO values is defined by writing to +/smack/cipso. Again, the format of data written to this special file +is highly restrictive, so the program smackcipso is provided to +ensure the writes are done properly. This program takes mappings +on the standard input and sends them to /smack/cipso properly. + +In addition to explicit mappings Smack supports direct CIPSO mappings. One +CIPSO level is used to indicate that the category set passed in the packet is +in fact an encoding of the Smack label. The level used is 250 by default. The +value can be read from /smack/direct and changed by writing to /smack/direct. + +Socket Attributes + +There are two attributes that are associated with sockets. These attributes +can only be set by privileged tasks, but any task can read them for their own +sockets. + + SMACK64IPIN: The Smack label of the task object. A privileged + program that will enforce policy may set this to the star label. + + SMACK64IPOUT: The Smack label transmitted with outgoing packets. + A privileged program may set this to match the label of another + task with which it hopes to communicate. + +Smack Netlabel Exceptions + +You will often find that your labeled application has to talk to the outside, +unlabeled world. To do this there's a special file /smack/netlabel where you can +add some exceptions in the form of : +@IP1 LABEL1 or +@IP2/MASK LABEL2 + +It means that your application will have unlabeled access to @IP1 if it has +write access on LABEL1, and access to the subnet @IP2/MASK if it has write +access on LABEL2. + +Entries in the /smack/netlabel file are matched by longest mask first, like in +classless IPv4 routing. + +A special label '@' and an option '-CIPSO' can be used there : +@ means Internet, any application with any label has access to it +-CIPSO means standard CIPSO networking + +If you don't know what CIPSO is and don't plan to use it, you can just do : +echo 127.0.0.1 -CIPSO > /smack/netlabel +echo 0.0.0.0/0 @ > /smack/netlabel + +If you use CIPSO on your 192.168.0.0/16 local network and need also unlabeled +Internet access, you can have : +echo 127.0.0.1 -CIPSO > /smack/netlabel +echo 192.168.0.0/16 -CIPSO > /smack/netlabel +echo 0.0.0.0/0 @ > /smack/netlabel + + +Writing Applications for Smack + +There are three sorts of applications that will run on a Smack system. How an +application interacts with Smack will determine what it will have to do to +work properly under Smack. + +Smack Ignorant Applications + +By far the majority of applications have no reason whatever to care about the +unique properties of Smack. Since invoking a program has no impact on the +Smack label associated with the process the only concern likely to arise is +whether the process has execute access to the program. + +Smack Relevant Applications + +Some programs can be improved by teaching them about Smack, but do not make +any security decisions themselves. The utility ls(1) is one example of such a +program. + +Smack Enforcing Applications + +These are special programs that not only know about Smack, but participate in +the enforcement of system policy. In most cases these are the programs that +set up user sessions. There are also network services that provide information +to processes running with various labels. + +File System Interfaces + +Smack maintains labels on file system objects using extended attributes. The +Smack label of a file, directory, or other file system object can be obtained +using getxattr(2). + + len = getxattr("/", "security.SMACK64", value, sizeof (value)); + +will put the Smack label of the root directory into value. A privileged +process can set the Smack label of a file system object with setxattr(2). + + len = strlen("Rubble"); + rc = setxattr("/foo", "security.SMACK64", "Rubble", len, 0); + +will set the Smack label of /foo to "Rubble" if the program has appropriate +privilege. + +Socket Interfaces + +The socket attributes can be read using fgetxattr(2). + +A privileged process can set the Smack label of outgoing packets with +fsetxattr(2). + + len = strlen("Rubble"); + rc = fsetxattr(fd, "security.SMACK64IPOUT", "Rubble", len, 0); + +will set the Smack label "Rubble" on packets going out from the socket if the +program has appropriate privilege. + + rc = fsetxattr(fd, "security.SMACK64IPIN, "*", strlen("*"), 0); + +will set the Smack label "*" as the object label against which incoming +packets will be checked if the program has appropriate privilege. + +Administration + +Smack supports some mount options: + + smackfsdef=label: specifies the label to give files that lack + the Smack label extended attribute. + + smackfsroot=label: specifies the label to assign the root of the + file system if it lacks the Smack extended attribute. + + smackfshat=label: specifies a label that must have read access to + all labels set on the filesystem. Not yet enforced. + + smackfsfloor=label: specifies a label to which all labels set on the + filesystem must have read access. Not yet enforced. + +These mount options apply to all file system types. + +Smack auditing + +If you want Smack auditing of security events, you need to set CONFIG_AUDIT +in your kernel configuration. +By default, all denied events will be audited. You can change this behavior by +writing a single character to the /smack/logging file : +0 : no logging +1 : log denied (default) +2 : log accepted +3 : log denied & accepted + +Events are logged as 'key=value' pairs, for each event you at least will get +the subjet, the object, the rights requested, the action, the kernel function +that triggered the event, plus other pairs depending on the type of event +audited. diff --git a/Documentation/security/apparmor.txt b/Documentation/security/apparmor.txt new file mode 100644 index 000000000000..93c1fd7d0635 --- /dev/null +++ b/Documentation/security/apparmor.txt @@ -0,0 +1,39 @@ +--- What is AppArmor? --- + +AppArmor is MAC style security extension for the Linux kernel. It implements +a task centered policy, with task "profiles" being created and loaded +from user space. Tasks on the system that do not have a profile defined for +them run in an unconfined state which is equivalent to standard Linux DAC +permissions. + +--- How to enable/disable --- + +set CONFIG_SECURITY_APPARMOR=y + +If AppArmor should be selected as the default security module then + set CONFIG_DEFAULT_SECURITY="apparmor" + and CONFIG_SECURITY_APPARMOR_BOOTPARAM_VALUE=1 + +Build the kernel + +If AppArmor is not the default security module it can be enabled by passing +security=apparmor on the kernel's command line. + +If AppArmor is the default security module it can be disabled by passing +apparmor=0, security=XXXX (where XXX is valid security module), on the +kernel's command line + +For AppArmor to enforce any restrictions beyond standard Linux DAC permissions +policy must be loaded into the kernel from user space (see the Documentation +and tools links). + +--- Documentation --- + +Documentation can be found on the wiki. + +--- Links --- + +Mailing List - apparmor@lists.ubuntu.com +Wiki - http://apparmor.wiki.kernel.org/ +User space tools - https://launchpad.net/apparmor +Kernel module - git://git.kernel.org/pub/scm/linux/kernel/git/jj/apparmor-dev.git diff --git a/Documentation/security/credentials.txt b/Documentation/security/credentials.txt new file mode 100644 index 000000000000..fc0366cbd7ce --- /dev/null +++ b/Documentation/security/credentials.txt @@ -0,0 +1,581 @@ + ==================== + CREDENTIALS IN LINUX + ==================== + +By: David Howells + +Contents: + + (*) Overview. + + (*) Types of credentials. + + (*) File markings. + + (*) Task credentials. + + - Immutable credentials. + - Accessing task credentials. + - Accessing another task's credentials. + - Altering credentials. + - Managing credentials. + + (*) Open file credentials. + + (*) Overriding the VFS's use of credentials. + + +======== +OVERVIEW +======== + +There are several parts to the security check performed by Linux when one +object acts upon another: + + (1) Objects. + + Objects are things in the system that may be acted upon directly by + userspace programs. Linux has a variety of actionable objects, including: + + - Tasks + - Files/inodes + - Sockets + - Message queues + - Shared memory segments + - Semaphores + - Keys + + As a part of the description of all these objects there is a set of + credentials. What's in the set depends on the type of object. + + (2) Object ownership. + + Amongst the credentials of most objects, there will be a subset that + indicates the ownership of that object. This is used for resource + accounting and limitation (disk quotas and task rlimits for example). + + In a standard UNIX filesystem, for instance, this will be defined by the + UID marked on the inode. + + (3) The objective context. + + Also amongst the credentials of those objects, there will be a subset that + indicates the 'objective context' of that object. This may or may not be + the same set as in (2) - in standard UNIX files, for instance, this is the + defined by the UID and the GID marked on the inode. + + The objective context is used as part of the security calculation that is + carried out when an object is acted upon. + + (4) Subjects. + + A subject is an object that is acting upon another object. + + Most of the objects in the system are inactive: they don't act on other + objects within the system. Processes/tasks are the obvious exception: + they do stuff; they access and manipulate things. + + Objects other than tasks may under some circumstances also be subjects. + For instance an open file may send SIGIO to a task using the UID and EUID + given to it by a task that called fcntl(F_SETOWN) upon it. In this case, + the file struct will have a subjective context too. + + (5) The subjective context. + + A subject has an additional interpretation of its credentials. A subset + of its credentials forms the 'subjective context'. The subjective context + is used as part of the security calculation that is carried out when a + subject acts. + + A Linux task, for example, has the FSUID, FSGID and the supplementary + group list for when it is acting upon a file - which are quite separate + from the real UID and GID that normally form the objective context of the + task. + + (6) Actions. + + Linux has a number of actions available that a subject may perform upon an + object. The set of actions available depends on the nature of the subject + and the object. + + Actions include reading, writing, creating and deleting files; forking or + signalling and tracing tasks. + + (7) Rules, access control lists and security calculations. + + When a subject acts upon an object, a security calculation is made. This + involves taking the subjective context, the objective context and the + action, and searching one or more sets of rules to see whether the subject + is granted or denied permission to act in the desired manner on the + object, given those contexts. + + There are two main sources of rules: + + (a) Discretionary access control (DAC): + + Sometimes the object will include sets of rules as part of its + description. This is an 'Access Control List' or 'ACL'. A Linux + file may supply more than one ACL. + + A traditional UNIX file, for example, includes a permissions mask that + is an abbreviated ACL with three fixed classes of subject ('user', + 'group' and 'other'), each of which may be granted certain privileges + ('read', 'write' and 'execute' - whatever those map to for the object + in question). UNIX file permissions do not allow the arbitrary + specification of subjects, however, and so are of limited use. + + A Linux file might also sport a POSIX ACL. This is a list of rules + that grants various permissions to arbitrary subjects. + + (b) Mandatory access control (MAC): + + The system as a whole may have one or more sets of rules that get + applied to all subjects and objects, regardless of their source. + SELinux and Smack are examples of this. + + In the case of SELinux and Smack, each object is given a label as part + of its credentials. When an action is requested, they take the + subject label, the object label and the action and look for a rule + that says that this action is either granted or denied. + + +==================== +TYPES OF CREDENTIALS +==================== + +The Linux kernel supports the following types of credentials: + + (1) Traditional UNIX credentials. + + Real User ID + Real Group ID + + The UID and GID are carried by most, if not all, Linux objects, even if in + some cases it has to be invented (FAT or CIFS files for example, which are + derived from Windows). These (mostly) define the objective context of + that object, with tasks being slightly different in some cases. + + Effective, Saved and FS User ID + Effective, Saved and FS Group ID + Supplementary groups + + These are additional credentials used by tasks only. Usually, an + EUID/EGID/GROUPS will be used as the subjective context, and real UID/GID + will be used as the objective. For tasks, it should be noted that this is + not always true. + + (2) Capabilities. + + Set of permitted capabilities + Set of inheritable capabilities + Set of effective capabilities + Capability bounding set + + These are only carried by tasks. They indicate superior capabilities + granted piecemeal to a task that an ordinary task wouldn't otherwise have. + These are manipulated implicitly by changes to the traditional UNIX + credentials, but can also be manipulated directly by the capset() system + call. + + The permitted capabilities are those caps that the process might grant + itself to its effective or permitted sets through capset(). This + inheritable set might also be so constrained. + + The effective capabilities are the ones that a task is actually allowed to + make use of itself. + + The inheritable capabilities are the ones that may get passed across + execve(). + + The bounding set limits the capabilities that may be inherited across + execve(), especially when a binary is executed that will execute as UID 0. + + (3) Secure management flags (securebits). + + These are only carried by tasks. These govern the way the above + credentials are manipulated and inherited over certain operations such as + execve(). They aren't used directly as objective or subjective + credentials. + + (4) Keys and keyrings. + + These are only carried by tasks. They carry and cache security tokens + that don't fit into the other standard UNIX credentials. They are for + making such things as network filesystem keys available to the file + accesses performed by processes, without the necessity of ordinary + programs having to know about security details involved. + + Keyrings are a special type of key. They carry sets of other keys and can + be searched for the desired key. Each process may subscribe to a number + of keyrings: + + Per-thread keying + Per-process keyring + Per-session keyring + + When a process accesses a key, if not already present, it will normally be + cached on one of these keyrings for future accesses to find. + + For more information on using keys, see Documentation/security/keys.txt. + + (5) LSM + + The Linux Security Module allows extra controls to be placed over the + operations that a task may do. Currently Linux supports two main + alternate LSM options: SELinux and Smack. + + Both work by labelling the objects in a system and then applying sets of + rules (policies) that say what operations a task with one label may do to + an object with another label. + + (6) AF_KEY + + This is a socket-based approach to credential management for networking + stacks [RFC 2367]. It isn't discussed by this document as it doesn't + interact directly with task and file credentials; rather it keeps system + level credentials. + + +When a file is opened, part of the opening task's subjective context is +recorded in the file struct created. This allows operations using that file +struct to use those credentials instead of the subjective context of the task +that issued the operation. An example of this would be a file opened on a +network filesystem where the credentials of the opened file should be presented +to the server, regardless of who is actually doing a read or a write upon it. + + +============= +FILE MARKINGS +============= + +Files on disk or obtained over the network may have annotations that form the +objective security context of that file. Depending on the type of filesystem, +this may include one or more of the following: + + (*) UNIX UID, GID, mode; + + (*) Windows user ID; + + (*) Access control list; + + (*) LSM security label; + + (*) UNIX exec privilege escalation bits (SUID/SGID); + + (*) File capabilities exec privilege escalation bits. + +These are compared to the task's subjective security context, and certain +operations allowed or disallowed as a result. In the case of execve(), the +privilege escalation bits come into play, and may allow the resulting process +extra privileges, based on the annotations on the executable file. + + +================ +TASK CREDENTIALS +================ + +In Linux, all of a task's credentials are held in (uid, gid) or through +(groups, keys, LSM security) a refcounted structure of type 'struct cred'. +Each task points to its credentials by a pointer called 'cred' in its +task_struct. + +Once a set of credentials has been prepared and committed, it may not be +changed, barring the following exceptions: + + (1) its reference count may be changed; + + (2) the reference count on the group_info struct it points to may be changed; + + (3) the reference count on the security data it points to may be changed; + + (4) the reference count on any keyrings it points to may be changed; + + (5) any keyrings it points to may be revoked, expired or have their security + attributes changed; and + + (6) the contents of any keyrings to which it points may be changed (the whole + point of keyrings being a shared set of credentials, modifiable by anyone + with appropriate access). + +To alter anything in the cred struct, the copy-and-replace principle must be +adhered to. First take a copy, then alter the copy and then use RCU to change +the task pointer to make it point to the new copy. There are wrappers to aid +with this (see below). + +A task may only alter its _own_ credentials; it is no longer permitted for a +task to alter another's credentials. This means the capset() system call is no +longer permitted to take any PID other than the one of the current process. +Also keyctl_instantiate() and keyctl_negate() functions no longer permit +attachment to process-specific keyrings in the requesting process as the +instantiating process may need to create them. + + +IMMUTABLE CREDENTIALS +--------------------- + +Once a set of credentials has been made public (by calling commit_creds() for +example), it must be considered immutable, barring two exceptions: + + (1) The reference count may be altered. + + (2) Whilst the keyring subscriptions of a set of credentials may not be + changed, the keyrings subscribed to may have their contents altered. + +To catch accidental credential alteration at compile time, struct task_struct +has _const_ pointers to its credential sets, as does struct file. Furthermore, +certain functions such as get_cred() and put_cred() operate on const pointers, +thus rendering casts unnecessary, but require to temporarily ditch the const +qualification to be able to alter the reference count. + + +ACCESSING TASK CREDENTIALS +-------------------------- + +A task being able to alter only its own credentials permits the current process +to read or replace its own credentials without the need for any form of locking +- which simplifies things greatly. It can just call: + + const struct cred *current_cred() + +to get a pointer to its credentials structure, and it doesn't have to release +it afterwards. + +There are convenience wrappers for retrieving specific aspects of a task's +credentials (the value is simply returned in each case): + + uid_t current_uid(void) Current's real UID + gid_t current_gid(void) Current's real GID + uid_t current_euid(void) Current's effective UID + gid_t current_egid(void) Current's effective GID + uid_t current_fsuid(void) Current's file access UID + gid_t current_fsgid(void) Current's file access GID + kernel_cap_t current_cap(void) Current's effective capabilities + void *current_security(void) Current's LSM security pointer + struct user_struct *current_user(void) Current's user account + +There are also convenience wrappers for retrieving specific associated pairs of +a task's credentials: + + void current_uid_gid(uid_t *, gid_t *); + void current_euid_egid(uid_t *, gid_t *); + void current_fsuid_fsgid(uid_t *, gid_t *); + +which return these pairs of values through their arguments after retrieving +them from the current task's credentials. + + +In addition, there is a function for obtaining a reference on the current +process's current set of credentials: + + const struct cred *get_current_cred(void); + +and functions for getting references to one of the credentials that don't +actually live in struct cred: + + struct user_struct *get_current_user(void); + struct group_info *get_current_groups(void); + +which get references to the current process's user accounting structure and +supplementary groups list respectively. + +Once a reference has been obtained, it must be released with put_cred(), +free_uid() or put_group_info() as appropriate. + + +ACCESSING ANOTHER TASK'S CREDENTIALS +------------------------------------ + +Whilst a task may access its own credentials without the need for locking, the +same is not true of a task wanting to access another task's credentials. It +must use the RCU read lock and rcu_dereference(). + +The rcu_dereference() is wrapped by: + + const struct cred *__task_cred(struct task_struct *task); + +This should be used inside the RCU read lock, as in the following example: + + void foo(struct task_struct *t, struct foo_data *f) + { + const struct cred *tcred; + ... + rcu_read_lock(); + tcred = __task_cred(t); + f->uid = tcred->uid; + f->gid = tcred->gid; + f->groups = get_group_info(tcred->groups); + rcu_read_unlock(); + ... + } + +Should it be necessary to hold another task's credentials for a long period of +time, and possibly to sleep whilst doing so, then the caller should get a +reference on them using: + + const struct cred *get_task_cred(struct task_struct *task); + +This does all the RCU magic inside of it. The caller must call put_cred() on +the credentials so obtained when they're finished with. + + [*] Note: The result of __task_cred() should not be passed directly to + get_cred() as this may race with commit_cred(). + +There are a couple of convenience functions to access bits of another task's +credentials, hiding the RCU magic from the caller: + + uid_t task_uid(task) Task's real UID + uid_t task_euid(task) Task's effective UID + +If the caller is holding the RCU read lock at the time anyway, then: + + __task_cred(task)->uid + __task_cred(task)->euid + +should be used instead. Similarly, if multiple aspects of a task's credentials +need to be accessed, RCU read lock should be used, __task_cred() called, the +result stored in a temporary pointer and then the credential aspects called +from that before dropping the lock. This prevents the potentially expensive +RCU magic from being invoked multiple times. + +Should some other single aspect of another task's credentials need to be +accessed, then this can be used: + + task_cred_xxx(task, member) + +where 'member' is a non-pointer member of the cred struct. For instance: + + uid_t task_cred_xxx(task, suid); + +will retrieve 'struct cred::suid' from the task, doing the appropriate RCU +magic. This may not be used for pointer members as what they point to may +disappear the moment the RCU read lock is dropped. + + +ALTERING CREDENTIALS +-------------------- + +As previously mentioned, a task may only alter its own credentials, and may not +alter those of another task. This means that it doesn't need to use any +locking to alter its own credentials. + +To alter the current process's credentials, a function should first prepare a +new set of credentials by calling: + + struct cred *prepare_creds(void); + +this locks current->cred_replace_mutex and then allocates and constructs a +duplicate of the current process's credentials, returning with the mutex still +held if successful. It returns NULL if not successful (out of memory). + +The mutex prevents ptrace() from altering the ptrace state of a process whilst +security checks on credentials construction and changing is taking place as +the ptrace state may alter the outcome, particularly in the case of execve(). + +The new credentials set should be altered appropriately, and any security +checks and hooks done. Both the current and the proposed sets of credentials +are available for this purpose as current_cred() will return the current set +still at this point. + + +When the credential set is ready, it should be committed to the current process +by calling: + + int commit_creds(struct cred *new); + +This will alter various aspects of the credentials and the process, giving the +LSM a chance to do likewise, then it will use rcu_assign_pointer() to actually +commit the new credentials to current->cred, it will release +current->cred_replace_mutex to allow ptrace() to take place, and it will notify +the scheduler and others of the changes. + +This function is guaranteed to return 0, so that it can be tail-called at the +end of such functions as sys_setresuid(). + +Note that this function consumes the caller's reference to the new credentials. +The caller should _not_ call put_cred() on the new credentials afterwards. + +Furthermore, once this function has been called on a new set of credentials, +those credentials may _not_ be changed further. + + +Should the security checks fail or some other error occur after prepare_creds() +has been called, then the following function should be invoked: + + void abort_creds(struct cred *new); + +This releases the lock on current->cred_replace_mutex that prepare_creds() got +and then releases the new credentials. + + +A typical credentials alteration function would look something like this: + + int alter_suid(uid_t suid) + { + struct cred *new; + int ret; + + new = prepare_creds(); + if (!new) + return -ENOMEM; + + new->suid = suid; + ret = security_alter_suid(new); + if (ret < 0) { + abort_creds(new); + return ret; + } + + return commit_creds(new); + } + + +MANAGING CREDENTIALS +-------------------- + +There are some functions to help manage credentials: + + (*) void put_cred(const struct cred *cred); + + This releases a reference to the given set of credentials. If the + reference count reaches zero, the credentials will be scheduled for + destruction by the RCU system. + + (*) const struct cred *get_cred(const struct cred *cred); + + This gets a reference on a live set of credentials, returning a pointer to + that set of credentials. + + (*) struct cred *get_new_cred(struct cred *cred); + + This gets a reference on a set of credentials that is under construction + and is thus still mutable, returning a pointer to that set of credentials. + + +===================== +OPEN FILE CREDENTIALS +===================== + +When a new file is opened, a reference is obtained on the opening task's +credentials and this is attached to the file struct as 'f_cred' in place of +'f_uid' and 'f_gid'. Code that used to access file->f_uid and file->f_gid +should now access file->f_cred->fsuid and file->f_cred->fsgid. + +It is safe to access f_cred without the use of RCU or locking because the +pointer will not change over the lifetime of the file struct, and nor will the +contents of the cred struct pointed to, barring the exceptions listed above +(see the Task Credentials section). + + +======================================= +OVERRIDING THE VFS'S USE OF CREDENTIALS +======================================= + +Under some circumstances it is desirable to override the credentials used by +the VFS, and that can be done by calling into such as vfs_mkdir() with a +different set of credentials. This is done in the following places: + + (*) sys_faccessat(). + + (*) do_coredump(). + + (*) nfs4recover.c. diff --git a/Documentation/security/keys-request-key.txt b/Documentation/security/keys-request-key.txt new file mode 100644 index 000000000000..51987bfecfed --- /dev/null +++ b/Documentation/security/keys-request-key.txt @@ -0,0 +1,202 @@ + =================== + KEY REQUEST SERVICE + =================== + +The key request service is part of the key retention service (refer to +Documentation/security/keys.txt). This document explains more fully how +the requesting algorithm works. + +The process starts by either the kernel requesting a service by calling +request_key*(): + + struct key *request_key(const struct key_type *type, + const char *description, + const char *callout_info); + +or: + + struct key *request_key_with_auxdata(const struct key_type *type, + const char *description, + const char *callout_info, + size_t callout_len, + void *aux); + +or: + + struct key *request_key_async(const struct key_type *type, + const char *description, + const char *callout_info, + size_t callout_len); + +or: + + struct key *request_key_async_with_auxdata(const struct key_type *type, + const char *description, + const char *callout_info, + size_t callout_len, + void *aux); + +Or by userspace invoking the request_key system call: + + key_serial_t request_key(const char *type, + const char *description, + const char *callout_info, + key_serial_t dest_keyring); + +The main difference between the access points is that the in-kernel interface +does not need to link the key to a keyring to prevent it from being immediately +destroyed. The kernel interface returns a pointer directly to the key, and +it's up to the caller to destroy the key. + +The request_key*_with_auxdata() calls are like the in-kernel request_key*() +calls, except that they permit auxiliary data to be passed to the upcaller (the +default is NULL). This is only useful for those key types that define their +own upcall mechanism rather than using /sbin/request-key. + +The two async in-kernel calls may return keys that are still in the process of +being constructed. The two non-async ones will wait for construction to +complete first. + +The userspace interface links the key to a keyring associated with the process +to prevent the key from going away, and returns the serial number of the key to +the caller. + + +The following example assumes that the key types involved don't define their +own upcall mechanisms. If they do, then those should be substituted for the +forking and execution of /sbin/request-key. + + +=========== +THE PROCESS +=========== + +A request proceeds in the following manner: + + (1) Process A calls request_key() [the userspace syscall calls the kernel + interface]. + + (2) request_key() searches the process's subscribed keyrings to see if there's + a suitable key there. If there is, it returns the key. If there isn't, + and callout_info is not set, an error is returned. Otherwise the process + proceeds to the next step. + + (3) request_key() sees that A doesn't have the desired key yet, so it creates + two things: + + (a) An uninstantiated key U of requested type and description. + + (b) An authorisation key V that refers to key U and notes that process A + is the context in which key U should be instantiated and secured, and + from which associated key requests may be satisfied. + + (4) request_key() then forks and executes /sbin/request-key with a new session + keyring that contains a link to auth key V. + + (5) /sbin/request-key assumes the authority associated with key U. + + (6) /sbin/request-key execs an appropriate program to perform the actual + instantiation. + + (7) The program may want to access another key from A's context (say a + Kerberos TGT key). It just requests the appropriate key, and the keyring + search notes that the session keyring has auth key V in its bottom level. + + This will permit it to then search the keyrings of process A with the + UID, GID, groups and security info of process A as if it was process A, + and come up with key W. + + (8) The program then does what it must to get the data with which to + instantiate key U, using key W as a reference (perhaps it contacts a + Kerberos server using the TGT) and then instantiates key U. + + (9) Upon instantiating key U, auth key V is automatically revoked so that it + may not be used again. + +(10) The program then exits 0 and request_key() deletes key V and returns key + U to the caller. + +This also extends further. If key W (step 7 above) didn't exist, key W would +be created uninstantiated, another auth key (X) would be created (as per step +3) and another copy of /sbin/request-key spawned (as per step 4); but the +context specified by auth key X will still be process A, as it was in auth key +V. + +This is because process A's keyrings can't simply be attached to +/sbin/request-key at the appropriate places because (a) execve will discard two +of them, and (b) it requires the same UID/GID/Groups all the way through. + + +==================================== +NEGATIVE INSTANTIATION AND REJECTION +==================================== + +Rather than instantiating a key, it is possible for the possessor of an +authorisation key to negatively instantiate a key that's under construction. +This is a short duration placeholder that causes any attempt at re-requesting +the key whilst it exists to fail with error ENOKEY if negated or the specified +error if rejected. + +This is provided to prevent excessive repeated spawning of /sbin/request-key +processes for a key that will never be obtainable. + +Should the /sbin/request-key process exit anything other than 0 or die on a +signal, the key under construction will be automatically negatively +instantiated for a short amount of time. + + +==================== +THE SEARCH ALGORITHM +==================== + +A search of any particular keyring proceeds in the following fashion: + + (1) When the key management code searches for a key (keyring_search_aux) it + firstly calls key_permission(SEARCH) on the keyring it's starting with, + if this denies permission, it doesn't search further. + + (2) It considers all the non-keyring keys within that keyring and, if any key + matches the criteria specified, calls key_permission(SEARCH) on it to see + if the key is allowed to be found. If it is, that key is returned; if + not, the search continues, and the error code is retained if of higher + priority than the one currently set. + + (3) It then considers all the keyring-type keys in the keyring it's currently + searching. It calls key_permission(SEARCH) on each keyring, and if this + grants permission, it recurses, executing steps (2) and (3) on that + keyring. + +The process stops immediately a valid key is found with permission granted to +use it. Any error from a previous match attempt is discarded and the key is +returned. + +When search_process_keyrings() is invoked, it performs the following searches +until one succeeds: + + (1) If extant, the process's thread keyring is searched. + + (2) If extant, the process's process keyring is searched. + + (3) The process's session keyring is searched. + + (4) If the process has assumed the authority associated with a request_key() + authorisation key then: + + (a) If extant, the calling process's thread keyring is searched. + + (b) If extant, the calling process's process keyring is searched. + + (c) The calling process's session keyring is searched. + +The moment one succeeds, all pending errors are discarded and the found key is +returned. + +Only if all these fail does the whole thing fail with the highest priority +error. Note that several errors may have come from LSM. + +The error priority is: + + EKEYREVOKED > EKEYEXPIRED > ENOKEY + +EACCES/EPERM are only returned on a direct search of a specific keyring where +the basal keyring does not grant Search permission. diff --git a/Documentation/security/keys-trusted-encrypted.txt b/Documentation/security/keys-trusted-encrypted.txt new file mode 100644 index 000000000000..8fb79bc1ac4b --- /dev/null +++ b/Documentation/security/keys-trusted-encrypted.txt @@ -0,0 +1,145 @@ + Trusted and Encrypted Keys + +Trusted and Encrypted Keys are two new key types added to the existing kernel +key ring service. Both of these new types are variable length symmetic keys, +and in both cases all keys are created in the kernel, and user space sees, +stores, and loads only encrypted blobs. Trusted Keys require the availability +of a Trusted Platform Module (TPM) chip for greater security, while Encrypted +Keys can be used on any system. All user level blobs, are displayed and loaded +in hex ascii for convenience, and are integrity verified. + +Trusted Keys use a TPM both to generate and to seal the keys. Keys are sealed +under a 2048 bit RSA key in the TPM, and optionally sealed to specified PCR +(integrity measurement) values, and only unsealed by the TPM, if PCRs and blob +integrity verifications match. A loaded Trusted Key can be updated with new +(future) PCR values, so keys are easily migrated to new pcr values, such as +when the kernel and initramfs are updated. The same key can have many saved +blobs under different PCR values, so multiple boots are easily supported. + +By default, trusted keys are sealed under the SRK, which has the default +authorization value (20 zeros). This can be set at takeownership time with the +trouser's utility: "tpm_takeownership -u -z". + +Usage: + keyctl add trusted name "new keylen [options]" ring + keyctl add trusted name "load hex_blob [pcrlock=pcrnum]" ring + keyctl update key "update [options]" + keyctl print keyid + + options: + keyhandle= ascii hex value of sealing key default 0x40000000 (SRK) + keyauth= ascii hex auth for sealing key default 0x00...i + (40 ascii zeros) + blobauth= ascii hex auth for sealed data default 0x00... + (40 ascii zeros) + blobauth= ascii hex auth for sealed data default 0x00... + (40 ascii zeros) + pcrinfo= ascii hex of PCR_INFO or PCR_INFO_LONG (no default) + pcrlock= pcr number to be extended to "lock" blob + migratable= 0|1 indicating permission to reseal to new PCR values, + default 1 (resealing allowed) + +"keyctl print" returns an ascii hex copy of the sealed key, which is in standard +TPM_STORED_DATA format. The key length for new keys are always in bytes. +Trusted Keys can be 32 - 128 bytes (256 - 1024 bits), the upper limit is to fit +within the 2048 bit SRK (RSA) keylength, with all necessary structure/padding. + +Encrypted keys do not depend on a TPM, and are faster, as they use AES for +encryption/decryption. New keys are created from kernel generated random +numbers, and are encrypted/decrypted using a specified 'master' key. The +'master' key can either be a trusted-key or user-key type. The main +disadvantage of encrypted keys is that if they are not rooted in a trusted key, +they are only as secure as the user key encrypting them. The master user key +should therefore be loaded in as secure a way as possible, preferably early in +boot. + +Usage: + keyctl add encrypted name "new key-type:master-key-name keylen" ring + keyctl add encrypted name "load hex_blob" ring + keyctl update keyid "update key-type:master-key-name" + +where 'key-type' is either 'trusted' or 'user'. + +Examples of trusted and encrypted key usage: + +Create and save a trusted key named "kmk" of length 32 bytes: + + $ keyctl add trusted kmk "new 32" @u + 440502848 + + $ keyctl show + Session Keyring + -3 --alswrv 500 500 keyring: _ses + 97833714 --alswrv 500 -1 \_ keyring: _uid.500 + 440502848 --alswrv 500 500 \_ trusted: kmk + + $ keyctl print 440502848 + 0101000000000000000001005d01b7e3f4a6be5709930f3b70a743cbb42e0cc95e18e915 + 3f60da455bbf1144ad12e4f92b452f966929f6105fd29ca28e4d4d5a031d068478bacb0b + 27351119f822911b0a11ba3d3498ba6a32e50dac7f32894dd890eb9ad578e4e292c83722 + a52e56a097e6a68b3f56f7a52ece0cdccba1eb62cad7d817f6dc58898b3ac15f36026fec + d568bd4a706cb60bb37be6d8f1240661199d640b66fb0fe3b079f97f450b9ef9c22c6d5d + dd379f0facd1cd020281dfa3c70ba21a3fa6fc2471dc6d13ecf8298b946f65345faa5ef0 + f1f8fff03ad0acb083725535636addb08d73dedb9832da198081e5deae84bfaf0409c22b + e4a8aea2b607ec96931e6f4d4fe563ba + + $ keyctl pipe 440502848 > kmk.blob + +Load a trusted key from the saved blob: + + $ keyctl add trusted kmk "load `cat kmk.blob`" @u + 268728824 + + $ keyctl print 268728824 + 0101000000000000000001005d01b7e3f4a6be5709930f3b70a743cbb42e0cc95e18e915 + 3f60da455bbf1144ad12e4f92b452f966929f6105fd29ca28e4d4d5a031d068478bacb0b + 27351119f822911b0a11ba3d3498ba6a32e50dac7f32894dd890eb9ad578e4e292c83722 + a52e56a097e6a68b3f56f7a52ece0cdccba1eb62cad7d817f6dc58898b3ac15f36026fec + d568bd4a706cb60bb37be6d8f1240661199d640b66fb0fe3b079f97f450b9ef9c22c6d5d + dd379f0facd1cd020281dfa3c70ba21a3fa6fc2471dc6d13ecf8298b946f65345faa5ef0 + f1f8fff03ad0acb083725535636addb08d73dedb9832da198081e5deae84bfaf0409c22b + e4a8aea2b607ec96931e6f4d4fe563ba + +Reseal a trusted key under new pcr values: + + $ keyctl update 268728824 "update pcrinfo=`cat pcr.blob`" + $ keyctl print 268728824 + 010100000000002c0002800093c35a09b70fff26e7a98ae786c641e678ec6ffb6b46d805 + 77c8a6377aed9d3219c6dfec4b23ffe3000001005d37d472ac8a44023fbb3d18583a4f73 + d3a076c0858f6f1dcaa39ea0f119911ff03f5406df4f7f27f41da8d7194f45c9f4e00f2e + df449f266253aa3f52e55c53de147773e00f0f9aca86c64d94c95382265968c354c5eab4 + 9638c5ae99c89de1e0997242edfb0b501744e11ff9762dfd951cffd93227cc513384e7e6 + e782c29435c7ec2edafaa2f4c1fe6e7a781b59549ff5296371b42133777dcc5b8b971610 + 94bc67ede19e43ddb9dc2baacad374a36feaf0314d700af0a65c164b7082401740e489c9 + 7ef6a24defe4846104209bf0c3eced7fa1a672ed5b125fc9d8cd88b476a658a4434644ef + df8ae9a178e9f83ba9f08d10fa47e4226b98b0702f06b3b8 + +Create and save an encrypted key "evm" using the above trusted key "kmk": + + $ keyctl add encrypted evm "new trusted:kmk 32" @u + 159771175 + + $ keyctl print 159771175 + trusted:kmk 32 2375725ad57798846a9bbd240de8906f006e66c03af53b1b382dbbc55 + be2a44616e4959430436dc4f2a7a9659aa60bb4652aeb2120f149ed197c564e024717c64 + 5972dcb82ab2dde83376d82b2e3c09ffc + + $ keyctl pipe 159771175 > evm.blob + +Load an encrypted key "evm" from saved blob: + + $ keyctl add encrypted evm "load `cat evm.blob`" @u + 831684262 + + $ keyctl print 831684262 + trusted:kmk 32 2375725ad57798846a9bbd240de8906f006e66c03af53b1b382dbbc55 + be2a44616e4959430436dc4f2a7a9659aa60bb4652aeb2120f149ed197c564e024717c64 + 5972dcb82ab2dde83376d82b2e3c09ffc + + +The initial consumer of trusted keys is EVM, which at boot time needs a high +quality symmetric key for HMAC protection of file metadata. The use of a +trusted key provides strong guarantees that the EVM key has not been +compromised by a user level problem, and when sealed to specific boot PCR +values, protects against boot and offline attacks. Other uses for trusted and +encrypted keys, such as for disk and file encryption are anticipated. diff --git a/Documentation/security/keys.txt b/Documentation/security/keys.txt new file mode 100644 index 000000000000..4d75931d2d79 --- /dev/null +++ b/Documentation/security/keys.txt @@ -0,0 +1,1290 @@ + ============================ + KERNEL KEY RETENTION SERVICE + ============================ + +This service allows cryptographic keys, authentication tokens, cross-domain +user mappings, and similar to be cached in the kernel for the use of +filesystems and other kernel services. + +Keyrings are permitted; these are a special type of key that can hold links to +other keys. Processes each have three standard keyring subscriptions that a +kernel service can search for relevant keys. + +The key service can be configured on by enabling: + + "Security options"/"Enable access key retention support" (CONFIG_KEYS) + +This document has the following sections: + + - Key overview + - Key service overview + - Key access permissions + - SELinux support + - New procfs files + - Userspace system call interface + - Kernel services + - Notes on accessing payload contents + - Defining a key type + - Request-key callback service + - Garbage collection + + +============ +KEY OVERVIEW +============ + +In this context, keys represent units of cryptographic data, authentication +tokens, keyrings, etc.. These are represented in the kernel by struct key. + +Each key has a number of attributes: + + - A serial number. + - A type. + - A description (for matching a key in a search). + - Access control information. + - An expiry time. + - A payload. + - State. + + + (*) Each key is issued a serial number of type key_serial_t that is unique for + the lifetime of that key. All serial numbers are positive non-zero 32-bit + integers. + + Userspace programs can use a key's serial numbers as a way to gain access + to it, subject to permission checking. + + (*) Each key is of a defined "type". Types must be registered inside the + kernel by a kernel service (such as a filesystem) before keys of that type + can be added or used. Userspace programs cannot define new types directly. + + Key types are represented in the kernel by struct key_type. This defines a + number of operations that can be performed on a key of that type. + + Should a type be removed from the system, all the keys of that type will + be invalidated. + + (*) Each key has a description. This should be a printable string. The key + type provides an operation to perform a match between the description on a + key and a criterion string. + + (*) Each key has an owner user ID, a group ID and a permissions mask. These + are used to control what a process may do to a key from userspace, and + whether a kernel service will be able to find the key. + + (*) Each key can be set to expire at a specific time by the key type's + instantiation function. Keys can also be immortal. + + (*) Each key can have a payload. This is a quantity of data that represent the + actual "key". In the case of a keyring, this is a list of keys to which + the keyring links; in the case of a user-defined key, it's an arbitrary + blob of data. + + Having a payload is not required; and the payload can, in fact, just be a + value stored in the struct key itself. + + When a key is instantiated, the key type's instantiation function is + called with a blob of data, and that then creates the key's payload in + some way. + + Similarly, when userspace wants to read back the contents of the key, if + permitted, another key type operation will be called to convert the key's + attached payload back into a blob of data. + + (*) Each key can be in one of a number of basic states: + + (*) Uninstantiated. The key exists, but does not have any data attached. + Keys being requested from userspace will be in this state. + + (*) Instantiated. This is the normal state. The key is fully formed, and + has data attached. + + (*) Negative. This is a relatively short-lived state. The key acts as a + note saying that a previous call out to userspace failed, and acts as + a throttle on key lookups. A negative key can be updated to a normal + state. + + (*) Expired. Keys can have lifetimes set. If their lifetime is exceeded, + they traverse to this state. An expired key can be updated back to a + normal state. + + (*) Revoked. A key is put in this state by userspace action. It can't be + found or operated upon (apart from by unlinking it). + + (*) Dead. The key's type was unregistered, and so the key is now useless. + +Keys in the last three states are subject to garbage collection. See the +section on "Garbage collection". + + +==================== +KEY SERVICE OVERVIEW +==================== + +The key service provides a number of features besides keys: + + (*) The key service defines two special key types: + + (+) "keyring" + + Keyrings are special keys that contain a list of other keys. Keyring + lists can be modified using various system calls. Keyrings should not + be given a payload when created. + + (+) "user" + + A key of this type has a description and a payload that are arbitrary + blobs of data. These can be created, updated and read by userspace, + and aren't intended for use by kernel services. + + (*) Each process subscribes to three keyrings: a thread-specific keyring, a + process-specific keyring, and a session-specific keyring. + + The thread-specific keyring is discarded from the child when any sort of + clone, fork, vfork or execve occurs. A new keyring is created only when + required. + + The process-specific keyring is replaced with an empty one in the child on + clone, fork, vfork unless CLONE_THREAD is supplied, in which case it is + shared. execve also discards the process's process keyring and creates a + new one. + + The session-specific keyring is persistent across clone, fork, vfork and + execve, even when the latter executes a set-UID or set-GID binary. A + process can, however, replace its current session keyring with a new one + by using PR_JOIN_SESSION_KEYRING. It is permitted to request an anonymous + new one, or to attempt to create or join one of a specific name. + + The ownership of the thread keyring changes when the real UID and GID of + the thread changes. + + (*) Each user ID resident in the system holds two special keyrings: a user + specific keyring and a default user session keyring. The default session + keyring is initialised with a link to the user-specific keyring. + + When a process changes its real UID, if it used to have no session key, it + will be subscribed to the default session key for the new UID. + + If a process attempts to access its session key when it doesn't have one, + it will be subscribed to the default for its current UID. + + (*) Each user has two quotas against which the keys they own are tracked. One + limits the total number of keys and keyrings, the other limits the total + amount of description and payload space that can be consumed. + + The user can view information on this and other statistics through procfs + files. The root user may also alter the quota limits through sysctl files + (see the section "New procfs files"). + + Process-specific and thread-specific keyrings are not counted towards a + user's quota. + + If a system call that modifies a key or keyring in some way would put the + user over quota, the operation is refused and error EDQUOT is returned. + + (*) There's a system call interface by which userspace programs can create and + manipulate keys and keyrings. + + (*) There's a kernel interface by which services can register types and search + for keys. + + (*) There's a way for the a search done from the kernel to call back to + userspace to request a key that can't be found in a process's keyrings. + + (*) An optional filesystem is available through which the key database can be + viewed and manipulated. + + +====================== +KEY ACCESS PERMISSIONS +====================== + +Keys have an owner user ID, a group access ID, and a permissions mask. The mask +has up to eight bits each for possessor, user, group and other access. Only +six of each set of eight bits are defined. These permissions granted are: + + (*) View + + This permits a key or keyring's attributes to be viewed - including key + type and description. + + (*) Read + + This permits a key's payload to be viewed or a keyring's list of linked + keys. + + (*) Write + + This permits a key's payload to be instantiated or updated, or it allows a + link to be added to or removed from a keyring. + + (*) Search + + This permits keyrings to be searched and keys to be found. Searches can + only recurse into nested keyrings that have search permission set. + + (*) Link + + This permits a key or keyring to be linked to. To create a link from a + keyring to a key, a process must have Write permission on the keyring and + Link permission on the key. + + (*) Set Attribute + + This permits a key's UID, GID and permissions mask to be changed. + +For changing the ownership, group ID or permissions mask, being the owner of +the key or having the sysadmin capability is sufficient. + + +=============== +SELINUX SUPPORT +=============== + +The security class "key" has been added to SELinux so that mandatory access +controls can be applied to keys created within various contexts. This support +is preliminary, and is likely to change quite significantly in the near future. +Currently, all of the basic permissions explained above are provided in SELinux +as well; SELinux is simply invoked after all basic permission checks have been +performed. + +The value of the file /proc/self/attr/keycreate influences the labeling of +newly-created keys. If the contents of that file correspond to an SELinux +security context, then the key will be assigned that context. Otherwise, the +key will be assigned the current context of the task that invoked the key +creation request. Tasks must be granted explicit permission to assign a +particular context to newly-created keys, using the "create" permission in the +key security class. + +The default keyrings associated with users will be labeled with the default +context of the user if and only if the login programs have been instrumented to +properly initialize keycreate during the login process. Otherwise, they will +be labeled with the context of the login program itself. + +Note, however, that the default keyrings associated with the root user are +labeled with the default kernel context, since they are created early in the +boot process, before root has a chance to log in. + +The keyrings associated with new threads are each labeled with the context of +their associated thread, and both session and process keyrings are handled +similarly. + + +================ +NEW PROCFS FILES +================ + +Two files have been added to procfs by which an administrator can find out +about the status of the key service: + + (*) /proc/keys + + This lists the keys that are currently viewable by the task reading the + file, giving information about their type, description and permissions. + It is not possible to view the payload of the key this way, though some + information about it may be given. + + The only keys included in the list are those that grant View permission to + the reading process whether or not it possesses them. Note that LSM + security checks are still performed, and may further filter out keys that + the current process is not authorised to view. + + The contents of the file look like this: + + SERIAL FLAGS USAGE EXPY PERM UID GID TYPE DESCRIPTION: SUMMARY + 00000001 I----- 39 perm 1f3f0000 0 0 keyring _uid_ses.0: 1/4 + 00000002 I----- 2 perm 1f3f0000 0 0 keyring _uid.0: empty + 00000007 I----- 1 perm 1f3f0000 0 0 keyring _pid.1: empty + 0000018d I----- 1 perm 1f3f0000 0 0 keyring _pid.412: empty + 000004d2 I--Q-- 1 perm 1f3f0000 32 -1 keyring _uid.32: 1/4 + 000004d3 I--Q-- 3 perm 1f3f0000 32 -1 keyring _uid_ses.32: empty + 00000892 I--QU- 1 perm 1f000000 0 0 user metal:copper: 0 + 00000893 I--Q-N 1 35s 1f3f0000 0 0 user metal:silver: 0 + 00000894 I--Q-- 1 10h 003f0000 0 0 user metal:gold: 0 + + The flags are: + + I Instantiated + R Revoked + D Dead + Q Contributes to user's quota + U Under construction by callback to userspace + N Negative key + + This file must be enabled at kernel configuration time as it allows anyone + to list the keys database. + + (*) /proc/key-users + + This file lists the tracking data for each user that has at least one key + on the system. Such data includes quota information and statistics: + + [root@andromeda root]# cat /proc/key-users + 0: 46 45/45 1/100 13/10000 + 29: 2 2/2 2/100 40/10000 + 32: 2 2/2 2/100 40/10000 + 38: 2 2/2 2/100 40/10000 + + The format of each line is + : User ID to which this applies + Structure refcount + / Total number of keys and number instantiated + / Key count quota + / Key size quota + + +Four new sysctl files have been added also for the purpose of controlling the +quota limits on keys: + + (*) /proc/sys/kernel/keys/root_maxkeys + /proc/sys/kernel/keys/root_maxbytes + + These files hold the maximum number of keys that root may have and the + maximum total number of bytes of data that root may have stored in those + keys. + + (*) /proc/sys/kernel/keys/maxkeys + /proc/sys/kernel/keys/maxbytes + + These files hold the maximum number of keys that each non-root user may + have and the maximum total number of bytes of data that each of those + users may have stored in their keys. + +Root may alter these by writing each new limit as a decimal number string to +the appropriate file. + + +=============================== +USERSPACE SYSTEM CALL INTERFACE +=============================== + +Userspace can manipulate keys directly through three new syscalls: add_key, +request_key and keyctl. The latter provides a number of functions for +manipulating keys. + +When referring to a key directly, userspace programs should use the key's +serial number (a positive 32-bit integer). However, there are some special +values available for referring to special keys and keyrings that relate to the +process making the call: + + CONSTANT VALUE KEY REFERENCED + ============================== ====== =========================== + KEY_SPEC_THREAD_KEYRING -1 thread-specific keyring + KEY_SPEC_PROCESS_KEYRING -2 process-specific keyring + KEY_SPEC_SESSION_KEYRING -3 session-specific keyring + KEY_SPEC_USER_KEYRING -4 UID-specific keyring + KEY_SPEC_USER_SESSION_KEYRING -5 UID-session keyring + KEY_SPEC_GROUP_KEYRING -6 GID-specific keyring + KEY_SPEC_REQKEY_AUTH_KEY -7 assumed request_key() + authorisation key + + +The main syscalls are: + + (*) Create a new key of given type, description and payload and add it to the + nominated keyring: + + key_serial_t add_key(const char *type, const char *desc, + const void *payload, size_t plen, + key_serial_t keyring); + + If a key of the same type and description as that proposed already exists + in the keyring, this will try to update it with the given payload, or it + will return error EEXIST if that function is not supported by the key + type. The process must also have permission to write to the key to be able + to update it. The new key will have all user permissions granted and no + group or third party permissions. + + Otherwise, this will attempt to create a new key of the specified type and + description, and to instantiate it with the supplied payload and attach it + to the keyring. In this case, an error will be generated if the process + does not have permission to write to the keyring. + + The payload is optional, and the pointer can be NULL if not required by + the type. The payload is plen in size, and plen can be zero for an empty + payload. + + A new keyring can be generated by setting type "keyring", the keyring name + as the description (or NULL) and setting the payload to NULL. + + User defined keys can be created by specifying type "user". It is + recommended that a user defined key's description by prefixed with a type + ID and a colon, such as "krb5tgt:" for a Kerberos 5 ticket granting + ticket. + + Any other type must have been registered with the kernel in advance by a + kernel service such as a filesystem. + + The ID of the new or updated key is returned if successful. + + + (*) Search the process's keyrings for a key, potentially calling out to + userspace to create it. + + key_serial_t request_key(const char *type, const char *description, + const char *callout_info, + key_serial_t dest_keyring); + + This function searches all the process's keyrings in the order thread, + process, session for a matching key. This works very much like + KEYCTL_SEARCH, including the optional attachment of the discovered key to + a keyring. + + If a key cannot be found, and if callout_info is not NULL, then + /sbin/request-key will be invoked in an attempt to obtain a key. The + callout_info string will be passed as an argument to the program. + + See also Documentation/security/keys-request-key.txt. + + +The keyctl syscall functions are: + + (*) Map a special key ID to a real key ID for this process: + + key_serial_t keyctl(KEYCTL_GET_KEYRING_ID, key_serial_t id, + int create); + + The special key specified by "id" is looked up (with the key being created + if necessary) and the ID of the key or keyring thus found is returned if + it exists. + + If the key does not yet exist, the key will be created if "create" is + non-zero; and the error ENOKEY will be returned if "create" is zero. + + + (*) Replace the session keyring this process subscribes to with a new one: + + key_serial_t keyctl(KEYCTL_JOIN_SESSION_KEYRING, const char *name); + + If name is NULL, an anonymous keyring is created attached to the process + as its session keyring, displacing the old session keyring. + + If name is not NULL, if a keyring of that name exists, the process + attempts to attach it as the session keyring, returning an error if that + is not permitted; otherwise a new keyring of that name is created and + attached as the session keyring. + + To attach to a named keyring, the keyring must have search permission for + the process's ownership. + + The ID of the new session keyring is returned if successful. + + + (*) Update the specified key: + + long keyctl(KEYCTL_UPDATE, key_serial_t key, const void *payload, + size_t plen); + + This will try to update the specified key with the given payload, or it + will return error EOPNOTSUPP if that function is not supported by the key + type. The process must also have permission to write to the key to be able + to update it. + + The payload is of length plen, and may be absent or empty as for + add_key(). + + + (*) Revoke a key: + + long keyctl(KEYCTL_REVOKE, key_serial_t key); + + This makes a key unavailable for further operations. Further attempts to + use the key will be met with error EKEYREVOKED, and the key will no longer + be findable. + + + (*) Change the ownership of a key: + + long keyctl(KEYCTL_CHOWN, key_serial_t key, uid_t uid, gid_t gid); + + This function permits a key's owner and group ID to be changed. Either one + of uid or gid can be set to -1 to suppress that change. + + Only the superuser can change a key's owner to something other than the + key's current owner. Similarly, only the superuser can change a key's + group ID to something other than the calling process's group ID or one of + its group list members. + + + (*) Change the permissions mask on a key: + + long keyctl(KEYCTL_SETPERM, key_serial_t key, key_perm_t perm); + + This function permits the owner of a key or the superuser to change the + permissions mask on a key. + + Only bits the available bits are permitted; if any other bits are set, + error EINVAL will be returned. + + + (*) Describe a key: + + long keyctl(KEYCTL_DESCRIBE, key_serial_t key, char *buffer, + size_t buflen); + + This function returns a summary of the key's attributes (but not its + payload data) as a string in the buffer provided. + + Unless there's an error, it always returns the amount of data it could + produce, even if that's too big for the buffer, but it won't copy more + than requested to userspace. If the buffer pointer is NULL then no copy + will take place. + + A process must have view permission on the key for this function to be + successful. + + If successful, a string is placed in the buffer in the following format: + + ;;;; + + Where type and description are strings, uid and gid are decimal, and perm + is hexadecimal. A NUL character is included at the end of the string if + the buffer is sufficiently big. + + This can be parsed with + + sscanf(buffer, "%[^;];%d;%d;%o;%s", type, &uid, &gid, &mode, desc); + + + (*) Clear out a keyring: + + long keyctl(KEYCTL_CLEAR, key_serial_t keyring); + + This function clears the list of keys attached to a keyring. The calling + process must have write permission on the keyring, and it must be a + keyring (or else error ENOTDIR will result). + + + (*) Link a key into a keyring: + + long keyctl(KEYCTL_LINK, key_serial_t keyring, key_serial_t key); + + This function creates a link from the keyring to the key. The process must + have write permission on the keyring and must have link permission on the + key. + + Should the keyring not be a keyring, error ENOTDIR will result; and if the + keyring is full, error ENFILE will result. + + The link procedure checks the nesting of the keyrings, returning ELOOP if + it appears too deep or EDEADLK if the link would introduce a cycle. + + Any links within the keyring to keys that match the new key in terms of + type and description will be discarded from the keyring as the new one is + added. + + + (*) Unlink a key or keyring from another keyring: + + long keyctl(KEYCTL_UNLINK, key_serial_t keyring, key_serial_t key); + + This function looks through the keyring for the first link to the + specified key, and removes it if found. Subsequent links to that key are + ignored. The process must have write permission on the keyring. + + If the keyring is not a keyring, error ENOTDIR will result; and if the key + is not present, error ENOENT will be the result. + + + (*) Search a keyring tree for a key: + + key_serial_t keyctl(KEYCTL_SEARCH, key_serial_t keyring, + const char *type, const char *description, + key_serial_t dest_keyring); + + This searches the keyring tree headed by the specified keyring until a key + is found that matches the type and description criteria. Each keyring is + checked for keys before recursion into its children occurs. + + The process must have search permission on the top level keyring, or else + error EACCES will result. Only keyrings that the process has search + permission on will be recursed into, and only keys and keyrings for which + a process has search permission can be matched. If the specified keyring + is not a keyring, ENOTDIR will result. + + If the search succeeds, the function will attempt to link the found key + into the destination keyring if one is supplied (non-zero ID). All the + constraints applicable to KEYCTL_LINK apply in this case too. + + Error ENOKEY, EKEYREVOKED or EKEYEXPIRED will be returned if the search + fails. On success, the resulting key ID will be returned. + + + (*) Read the payload data from a key: + + long keyctl(KEYCTL_READ, key_serial_t keyring, char *buffer, + size_t buflen); + + This function attempts to read the payload data from the specified key + into the buffer. The process must have read permission on the key to + succeed. + + The returned data will be processed for presentation by the key type. For + instance, a keyring will return an array of key_serial_t entries + representing the IDs of all the keys to which it is subscribed. The user + defined key type will return its data as is. If a key type does not + implement this function, error EOPNOTSUPP will result. + + As much of the data as can be fitted into the buffer will be copied to + userspace if the buffer pointer is not NULL. + + On a successful return, the function will always return the amount of data + available rather than the amount copied. + + + (*) Instantiate a partially constructed key. + + long keyctl(KEYCTL_INSTANTIATE, key_serial_t key, + const void *payload, size_t plen, + key_serial_t keyring); + long keyctl(KEYCTL_INSTANTIATE_IOV, key_serial_t key, + const struct iovec *payload_iov, unsigned ioc, + key_serial_t keyring); + + If the kernel calls back to userspace to complete the instantiation of a + key, userspace should use this call to supply data for the key before the + invoked process returns, or else the key will be marked negative + automatically. + + The process must have write access on the key to be able to instantiate + it, and the key must be uninstantiated. + + If a keyring is specified (non-zero), the key will also be linked into + that keyring, however all the constraints applying in KEYCTL_LINK apply in + this case too. + + The payload and plen arguments describe the payload data as for add_key(). + + The payload_iov and ioc arguments describe the payload data in an iovec + array instead of a single buffer. + + + (*) Negatively instantiate a partially constructed key. + + long keyctl(KEYCTL_NEGATE, key_serial_t key, + unsigned timeout, key_serial_t keyring); + long keyctl(KEYCTL_REJECT, key_serial_t key, + unsigned timeout, unsigned error, key_serial_t keyring); + + If the kernel calls back to userspace to complete the instantiation of a + key, userspace should use this call mark the key as negative before the + invoked process returns if it is unable to fulfil the request. + + The process must have write access on the key to be able to instantiate + it, and the key must be uninstantiated. + + If a keyring is specified (non-zero), the key will also be linked into + that keyring, however all the constraints applying in KEYCTL_LINK apply in + this case too. + + If the key is rejected, future searches for it will return the specified + error code until the rejected key expires. Negating the key is the same + as rejecting the key with ENOKEY as the error code. + + + (*) Set the default request-key destination keyring. + + long keyctl(KEYCTL_SET_REQKEY_KEYRING, int reqkey_defl); + + This sets the default keyring to which implicitly requested keys will be + attached for this thread. reqkey_defl should be one of these constants: + + CONSTANT VALUE NEW DEFAULT KEYRING + ====================================== ====== ======================= + KEY_REQKEY_DEFL_NO_CHANGE -1 No change + KEY_REQKEY_DEFL_DEFAULT 0 Default[1] + KEY_REQKEY_DEFL_THREAD_KEYRING 1 Thread keyring + KEY_REQKEY_DEFL_PROCESS_KEYRING 2 Process keyring + KEY_REQKEY_DEFL_SESSION_KEYRING 3 Session keyring + KEY_REQKEY_DEFL_USER_KEYRING 4 User keyring + KEY_REQKEY_DEFL_USER_SESSION_KEYRING 5 User session keyring + KEY_REQKEY_DEFL_GROUP_KEYRING 6 Group keyring + + The old default will be returned if successful and error EINVAL will be + returned if reqkey_defl is not one of the above values. + + The default keyring can be overridden by the keyring indicated to the + request_key() system call. + + Note that this setting is inherited across fork/exec. + + [1] The default is: the thread keyring if there is one, otherwise + the process keyring if there is one, otherwise the session keyring if + there is one, otherwise the user default session keyring. + + + (*) Set the timeout on a key. + + long keyctl(KEYCTL_SET_TIMEOUT, key_serial_t key, unsigned timeout); + + This sets or clears the timeout on a key. The timeout can be 0 to clear + the timeout or a number of seconds to set the expiry time that far into + the future. + + The process must have attribute modification access on a key to set its + timeout. Timeouts may not be set with this function on negative, revoked + or expired keys. + + + (*) Assume the authority granted to instantiate a key + + long keyctl(KEYCTL_ASSUME_AUTHORITY, key_serial_t key); + + This assumes or divests the authority required to instantiate the + specified key. Authority can only be assumed if the thread has the + authorisation key associated with the specified key in its keyrings + somewhere. + + Once authority is assumed, searches for keys will also search the + requester's keyrings using the requester's security label, UID, GID and + groups. + + If the requested authority is unavailable, error EPERM will be returned, + likewise if the authority has been revoked because the target key is + already instantiated. + + If the specified key is 0, then any assumed authority will be divested. + + The assumed authoritative key is inherited across fork and exec. + + + (*) Get the LSM security context attached to a key. + + long keyctl(KEYCTL_GET_SECURITY, key_serial_t key, char *buffer, + size_t buflen) + + This function returns a string that represents the LSM security context + attached to a key in the buffer provided. + + Unless there's an error, it always returns the amount of data it could + produce, even if that's too big for the buffer, but it won't copy more + than requested to userspace. If the buffer pointer is NULL then no copy + will take place. + + A NUL character is included at the end of the string if the buffer is + sufficiently big. This is included in the returned count. If no LSM is + in force then an empty string will be returned. + + A process must have view permission on the key for this function to be + successful. + + + (*) Install the calling process's session keyring on its parent. + + long keyctl(KEYCTL_SESSION_TO_PARENT); + + This functions attempts to install the calling process's session keyring + on to the calling process's parent, replacing the parent's current session + keyring. + + The calling process must have the same ownership as its parent, the + keyring must have the same ownership as the calling process, the calling + process must have LINK permission on the keyring and the active LSM module + mustn't deny permission, otherwise error EPERM will be returned. + + Error ENOMEM will be returned if there was insufficient memory to complete + the operation, otherwise 0 will be returned to indicate success. + + The keyring will be replaced next time the parent process leaves the + kernel and resumes executing userspace. + + +=============== +KERNEL SERVICES +=============== + +The kernel services for key management are fairly simple to deal with. They can +be broken down into two areas: keys and key types. + +Dealing with keys is fairly straightforward. Firstly, the kernel service +registers its type, then it searches for a key of that type. It should retain +the key as long as it has need of it, and then it should release it. For a +filesystem or device file, a search would probably be performed during the open +call, and the key released upon close. How to deal with conflicting keys due to +two different users opening the same file is left to the filesystem author to +solve. + +To access the key manager, the following header must be #included: + + + +Specific key types should have a header file under include/keys/ that should be +used to access that type. For keys of type "user", for example, that would be: + + + +Note that there are two different types of pointers to keys that may be +encountered: + + (*) struct key * + + This simply points to the key structure itself. Key structures will be at + least four-byte aligned. + + (*) key_ref_t + + This is equivalent to a struct key *, but the least significant bit is set + if the caller "possesses" the key. By "possession" it is meant that the + calling processes has a searchable link to the key from one of its + keyrings. There are three functions for dealing with these: + + key_ref_t make_key_ref(const struct key *key, + unsigned long possession); + + struct key *key_ref_to_ptr(const key_ref_t key_ref); + + unsigned long is_key_possessed(const key_ref_t key_ref); + + The first function constructs a key reference from a key pointer and + possession information (which must be 0 or 1 and not any other value). + + The second function retrieves the key pointer from a reference and the + third retrieves the possession flag. + +When accessing a key's payload contents, certain precautions must be taken to +prevent access vs modification races. See the section "Notes on accessing +payload contents" for more information. + +(*) To search for a key, call: + + struct key *request_key(const struct key_type *type, + const char *description, + const char *callout_info); + + This is used to request a key or keyring with a description that matches + the description specified according to the key type's match function. This + permits approximate matching to occur. If callout_string is not NULL, then + /sbin/request-key will be invoked in an attempt to obtain the key from + userspace. In that case, callout_string will be passed as an argument to + the program. + + Should the function fail error ENOKEY, EKEYEXPIRED or EKEYREVOKED will be + returned. + + If successful, the key will have been attached to the default keyring for + implicitly obtained request-key keys, as set by KEYCTL_SET_REQKEY_KEYRING. + + See also Documentation/security/keys-request-key.txt. + + +(*) To search for a key, passing auxiliary data to the upcaller, call: + + struct key *request_key_with_auxdata(const struct key_type *type, + const char *description, + const void *callout_info, + size_t callout_len, + void *aux); + + This is identical to request_key(), except that the auxiliary data is + passed to the key_type->request_key() op if it exists, and the callout_info + is a blob of length callout_len, if given (the length may be 0). + + +(*) A key can be requested asynchronously by calling one of: + + struct key *request_key_async(const struct key_type *type, + const char *description, + const void *callout_info, + size_t callout_len); + + or: + + struct key *request_key_async_with_auxdata(const struct key_type *type, + const char *description, + const char *callout_info, + size_t callout_len, + void *aux); + + which are asynchronous equivalents of request_key() and + request_key_with_auxdata() respectively. + + These two functions return with the key potentially still under + construction. To wait for construction completion, the following should be + called: + + int wait_for_key_construction(struct key *key, bool intr); + + The function will wait for the key to finish being constructed and then + invokes key_validate() to return an appropriate value to indicate the state + of the key (0 indicates the key is usable). + + If intr is true, then the wait can be interrupted by a signal, in which + case error ERESTARTSYS will be returned. + + +(*) When it is no longer required, the key should be released using: + + void key_put(struct key *key); + + Or: + + void key_ref_put(key_ref_t key_ref); + + These can be called from interrupt context. If CONFIG_KEYS is not set then + the argument will not be parsed. + + +(*) Extra references can be made to a key by calling the following function: + + struct key *key_get(struct key *key); + + These need to be disposed of by calling key_put() when they've been + finished with. The key pointer passed in will be returned. If the pointer + is NULL or CONFIG_KEYS is not set then the key will not be dereferenced and + no increment will take place. + + +(*) A key's serial number can be obtained by calling: + + key_serial_t key_serial(struct key *key); + + If key is NULL or if CONFIG_KEYS is not set then 0 will be returned (in the + latter case without parsing the argument). + + +(*) If a keyring was found in the search, this can be further searched by: + + key_ref_t keyring_search(key_ref_t keyring_ref, + const struct key_type *type, + const char *description) + + This searches the keyring tree specified for a matching key. Error ENOKEY + is returned upon failure (use IS_ERR/PTR_ERR to determine). If successful, + the returned key will need to be released. + + The possession attribute from the keyring reference is used to control + access through the permissions mask and is propagated to the returned key + reference pointer if successful. + + +(*) To check the validity of a key, this function can be called: + + int validate_key(struct key *key); + + This checks that the key in question hasn't expired or and hasn't been + revoked. Should the key be invalid, error EKEYEXPIRED or EKEYREVOKED will + be returned. If the key is NULL or if CONFIG_KEYS is not set then 0 will be + returned (in the latter case without parsing the argument). + + +(*) To register a key type, the following function should be called: + + int register_key_type(struct key_type *type); + + This will return error EEXIST if a type of the same name is already + present. + + +(*) To unregister a key type, call: + + void unregister_key_type(struct key_type *type); + + +Under some circumstances, it may be desirable to deal with a bundle of keys. +The facility provides access to the keyring type for managing such a bundle: + + struct key_type key_type_keyring; + +This can be used with a function such as request_key() to find a specific +keyring in a process's keyrings. A keyring thus found can then be searched +with keyring_search(). Note that it is not possible to use request_key() to +search a specific keyring, so using keyrings in this way is of limited utility. + + +=================================== +NOTES ON ACCESSING PAYLOAD CONTENTS +=================================== + +The simplest payload is just a number in key->payload.value. In this case, +there's no need to indulge in RCU or locking when accessing the payload. + +More complex payload contents must be allocated and a pointer to them set in +key->payload.data. One of the following ways must be selected to access the +data: + + (1) Unmodifiable key type. + + If the key type does not have a modify method, then the key's payload can + be accessed without any form of locking, provided that it's known to be + instantiated (uninstantiated keys cannot be "found"). + + (2) The key's semaphore. + + The semaphore could be used to govern access to the payload and to control + the payload pointer. It must be write-locked for modifications and would + have to be read-locked for general access. The disadvantage of doing this + is that the accessor may be required to sleep. + + (3) RCU. + + RCU must be used when the semaphore isn't already held; if the semaphore + is held then the contents can't change under you unexpectedly as the + semaphore must still be used to serialise modifications to the key. The + key management code takes care of this for the key type. + + However, this means using: + + rcu_read_lock() ... rcu_dereference() ... rcu_read_unlock() + + to read the pointer, and: + + rcu_dereference() ... rcu_assign_pointer() ... call_rcu() + + to set the pointer and dispose of the old contents after a grace period. + Note that only the key type should ever modify a key's payload. + + Furthermore, an RCU controlled payload must hold a struct rcu_head for the + use of call_rcu() and, if the payload is of variable size, the length of + the payload. key->datalen cannot be relied upon to be consistent with the + payload just dereferenced if the key's semaphore is not held. + + +=================== +DEFINING A KEY TYPE +=================== + +A kernel service may want to define its own key type. For instance, an AFS +filesystem might want to define a Kerberos 5 ticket key type. To do this, it +author fills in a key_type struct and registers it with the system. + +Source files that implement key types should include the following header file: + + + +The structure has a number of fields, some of which are mandatory: + + (*) const char *name + + The name of the key type. This is used to translate a key type name + supplied by userspace into a pointer to the structure. + + + (*) size_t def_datalen + + This is optional - it supplies the default payload data length as + contributed to the quota. If the key type's payload is always or almost + always the same size, then this is a more efficient way to do things. + + The data length (and quota) on a particular key can always be changed + during instantiation or update by calling: + + int key_payload_reserve(struct key *key, size_t datalen); + + With the revised data length. Error EDQUOT will be returned if this is not + viable. + + + (*) int (*vet_description)(const char *description); + + This optional method is called to vet a key description. If the key type + doesn't approve of the key description, it may return an error, otherwise + it should return 0. + + + (*) int (*instantiate)(struct key *key, const void *data, size_t datalen); + + This method is called to attach a payload to a key during construction. + The payload attached need not bear any relation to the data passed to this + function. + + If the amount of data attached to the key differs from the size in + keytype->def_datalen, then key_payload_reserve() should be called. + + This method does not have to lock the key in order to attach a payload. + The fact that KEY_FLAG_INSTANTIATED is not set in key->flags prevents + anything else from gaining access to the key. + + It is safe to sleep in this method. + + + (*) int (*update)(struct key *key, const void *data, size_t datalen); + + If this type of key can be updated, then this method should be provided. + It is called to update a key's payload from the blob of data provided. + + key_payload_reserve() should be called if the data length might change + before any changes are actually made. Note that if this succeeds, the type + is committed to changing the key because it's already been altered, so all + memory allocation must be done first. + + The key will have its semaphore write-locked before this method is called, + but this only deters other writers; any changes to the key's payload must + be made under RCU conditions, and call_rcu() must be used to dispose of + the old payload. + + key_payload_reserve() should be called before the changes are made, but + after all allocations and other potentially failing function calls are + made. + + It is safe to sleep in this method. + + + (*) int (*match)(const struct key *key, const void *desc); + + This method is called to match a key against a description. It should + return non-zero if the two match, zero if they don't. + + This method should not need to lock the key in any way. The type and + description can be considered invariant, and the payload should not be + accessed (the key may not yet be instantiated). + + It is not safe to sleep in this method; the caller may hold spinlocks. + + + (*) void (*revoke)(struct key *key); + + This method is optional. It is called to discard part of the payload + data upon a key being revoked. The caller will have the key semaphore + write-locked. + + It is safe to sleep in this method, though care should be taken to avoid + a deadlock against the key semaphore. + + + (*) void (*destroy)(struct key *key); + + This method is optional. It is called to discard the payload data on a key + when it is being destroyed. + + This method does not need to lock the key to access the payload; it can + consider the key as being inaccessible at this time. Note that the key's + type may have been changed before this function is called. + + It is not safe to sleep in this method; the caller may hold spinlocks. + + + (*) void (*describe)(const struct key *key, struct seq_file *p); + + This method is optional. It is called during /proc/keys reading to + summarise a key's description and payload in text form. + + This method will be called with the RCU read lock held. rcu_dereference() + should be used to read the payload pointer if the payload is to be + accessed. key->datalen cannot be trusted to stay consistent with the + contents of the payload. + + The description will not change, though the key's state may. + + It is not safe to sleep in this method; the RCU read lock is held by the + caller. + + + (*) long (*read)(const struct key *key, char __user *buffer, size_t buflen); + + This method is optional. It is called by KEYCTL_READ to translate the + key's payload into something a blob of data for userspace to deal with. + Ideally, the blob should be in the same format as that passed in to the + instantiate and update methods. + + If successful, the blob size that could be produced should be returned + rather than the size copied. + + This method will be called with the key's semaphore read-locked. This will + prevent the key's payload changing. It is not necessary to use RCU locking + when accessing the key's payload. It is safe to sleep in this method, such + as might happen when the userspace buffer is accessed. + + + (*) int (*request_key)(struct key_construction *cons, const char *op, + void *aux); + + This method is optional. If provided, request_key() and friends will + invoke this function rather than upcalling to /sbin/request-key to operate + upon a key of this type. + + The aux parameter is as passed to request_key_async_with_auxdata() and + similar or is NULL otherwise. Also passed are the construction record for + the key to be operated upon and the operation type (currently only + "create"). + + This method is permitted to return before the upcall is complete, but the + following function must be called under all circumstances to complete the + instantiation process, whether or not it succeeds, whether or not there's + an error: + + void complete_request_key(struct key_construction *cons, int error); + + The error parameter should be 0 on success, -ve on error. The + construction record is destroyed by this action and the authorisation key + will be revoked. If an error is indicated, the key under construction + will be negatively instantiated if it wasn't already instantiated. + + If this method returns an error, that error will be returned to the + caller of request_key*(). complete_request_key() must be called prior to + returning. + + The key under construction and the authorisation key can be found in the + key_construction struct pointed to by cons: + + (*) struct key *key; + + The key under construction. + + (*) struct key *authkey; + + The authorisation key. + + +============================ +REQUEST-KEY CALLBACK SERVICE +============================ + +To create a new key, the kernel will attempt to execute the following command +line: + + /sbin/request-key create \ + + + is the key being constructed, and the three keyrings are the process +keyrings from the process that caused the search to be issued. These are +included for two reasons: + + (1) There may be an authentication token in one of the keyrings that is + required to obtain the key, eg: a Kerberos Ticket-Granting Ticket. + + (2) The new key should probably be cached in one of these rings. + +This program should set it UID and GID to those specified before attempting to +access any more keys. It may then look around for a user specific process to +hand the request off to (perhaps a path held in placed in another key by, for +example, the KDE desktop manager). + +The program (or whatever it calls) should finish construction of the key by +calling KEYCTL_INSTANTIATE or KEYCTL_INSTANTIATE_IOV, which also permits it to +cache the key in one of the keyrings (probably the session ring) before +returning. Alternatively, the key can be marked as negative with KEYCTL_NEGATE +or KEYCTL_REJECT; this also permits the key to be cached in one of the +keyrings. + +If it returns with the key remaining in the unconstructed state, the key will +be marked as being negative, it will be added to the session keyring, and an +error will be returned to the key requestor. + +Supplementary information may be provided from whoever or whatever invoked this +service. This will be passed as the parameter. If no such +information was made available, then "-" will be passed as this parameter +instead. + + +Similarly, the kernel may attempt to update an expired or a soon to expire key +by executing: + + /sbin/request-key update \ + + +In this case, the program isn't required to actually attach the key to a ring; +the rings are provided for reference. + + +================== +GARBAGE COLLECTION +================== + +Dead keys (for which the type has been removed) will be automatically unlinked +from those keyrings that point to them and deleted as soon as possible by a +background garbage collector. + +Similarly, revoked and expired keys will be garbage collected, but only after a +certain amount of time has passed. This time is set as a number of seconds in: + + /proc/sys/kernel/keys/gc_delay diff --git a/Documentation/security/tomoyo.txt b/Documentation/security/tomoyo.txt new file mode 100644 index 000000000000..200a2d37cbc8 --- /dev/null +++ b/Documentation/security/tomoyo.txt @@ -0,0 +1,55 @@ +--- What is TOMOYO? --- + +TOMOYO is a name-based MAC extension (LSM module) for the Linux kernel. + +LiveCD-based tutorials are available at +http://tomoyo.sourceforge.jp/1.7/1st-step/ubuntu10.04-live/ +http://tomoyo.sourceforge.jp/1.7/1st-step/centos5-live/ . +Though these tutorials use non-LSM version of TOMOYO, they are useful for you +to know what TOMOYO is. + +--- How to enable TOMOYO? --- + +Build the kernel with CONFIG_SECURITY_TOMOYO=y and pass "security=tomoyo" on +kernel's command line. + +Please see http://tomoyo.sourceforge.jp/2.3/ for details. + +--- Where is documentation? --- + +User <-> Kernel interface documentation is available at +http://tomoyo.sourceforge.jp/2.3/policy-reference.html . + +Materials we prepared for seminars and symposiums are available at +http://sourceforge.jp/projects/tomoyo/docs/?category_id=532&language_id=1 . +Below lists are chosen from three aspects. + +What is TOMOYO? + TOMOYO Linux Overview + http://sourceforge.jp/projects/tomoyo/docs/lca2009-takeda.pdf + TOMOYO Linux: pragmatic and manageable security for Linux + http://sourceforge.jp/projects/tomoyo/docs/freedomhectaipei-tomoyo.pdf + TOMOYO Linux: A Practical Method to Understand and Protect Your Own Linux Box + http://sourceforge.jp/projects/tomoyo/docs/PacSec2007-en-no-demo.pdf + +What can TOMOYO do? + Deep inside TOMOYO Linux + http://sourceforge.jp/projects/tomoyo/docs/lca2009-kumaneko.pdf + The role of "pathname based access control" in security. + http://sourceforge.jp/projects/tomoyo/docs/lfj2008-bof.pdf + +History of TOMOYO? + Realities of Mainlining + http://sourceforge.jp/projects/tomoyo/docs/lfj2008.pdf + +--- What is future plan? --- + +We believe that inode based security and name based security are complementary +and both should be used together. But unfortunately, so far, we cannot enable +multiple LSM modules at the same time. We feel sorry that you have to give up +SELinux/SMACK/AppArmor etc. when you want to use TOMOYO. + +We hope that LSM becomes stackable in future. Meanwhile, you can use non-LSM +version of TOMOYO, available at http://tomoyo.sourceforge.jp/1.7/ . +LSM version of TOMOYO is a subset of non-LSM version of TOMOYO. We are planning +to port non-LSM version's functionalities to LSM versions. diff --git a/Documentation/tomoyo.txt b/Documentation/tomoyo.txt deleted file mode 100644 index 200a2d37cbc8..000000000000 --- a/Documentation/tomoyo.txt +++ /dev/null @@ -1,55 +0,0 @@ ---- What is TOMOYO? --- - -TOMOYO is a name-based MAC extension (LSM module) for the Linux kernel. - -LiveCD-based tutorials are available at -http://tomoyo.sourceforge.jp/1.7/1st-step/ubuntu10.04-live/ -http://tomoyo.sourceforge.jp/1.7/1st-step/centos5-live/ . -Though these tutorials use non-LSM version of TOMOYO, they are useful for you -to know what TOMOYO is. - ---- How to enable TOMOYO? --- - -Build the kernel with CONFIG_SECURITY_TOMOYO=y and pass "security=tomoyo" on -kernel's command line. - -Please see http://tomoyo.sourceforge.jp/2.3/ for details. - ---- Where is documentation? --- - -User <-> Kernel interface documentation is available at -http://tomoyo.sourceforge.jp/2.3/policy-reference.html . - -Materials we prepared for seminars and symposiums are available at -http://sourceforge.jp/projects/tomoyo/docs/?category_id=532&language_id=1 . -Below lists are chosen from three aspects. - -What is TOMOYO? - TOMOYO Linux Overview - http://sourceforge.jp/projects/tomoyo/docs/lca2009-takeda.pdf - TOMOYO Linux: pragmatic and manageable security for Linux - http://sourceforge.jp/projects/tomoyo/docs/freedomhectaipei-tomoyo.pdf - TOMOYO Linux: A Practical Method to Understand and Protect Your Own Linux Box - http://sourceforge.jp/projects/tomoyo/docs/PacSec2007-en-no-demo.pdf - -What can TOMOYO do? - Deep inside TOMOYO Linux - http://sourceforge.jp/projects/tomoyo/docs/lca2009-kumaneko.pdf - The role of "pathname based access control" in security. - http://sourceforge.jp/projects/tomoyo/docs/lfj2008-bof.pdf - -History of TOMOYO? - Realities of Mainlining - http://sourceforge.jp/projects/tomoyo/docs/lfj2008.pdf - ---- What is future plan? --- - -We believe that inode based security and name based security are complementary -and both should be used together. But unfortunately, so far, we cannot enable -multiple LSM modules at the same time. We feel sorry that you have to give up -SELinux/SMACK/AppArmor etc. when you want to use TOMOYO. - -We hope that LSM becomes stackable in future. Meanwhile, you can use non-LSM -version of TOMOYO, available at http://tomoyo.sourceforge.jp/1.7/ . -LSM version of TOMOYO is a subset of non-LSM version of TOMOYO. We are planning -to port non-LSM version's functionalities to LSM versions. diff --git a/MAINTAINERS b/MAINTAINERS index 69f19f10314a..3fa170ba5f98 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -3705,7 +3705,7 @@ KEYS/KEYRINGS: M: David Howells L: keyrings@linux-nfs.org S: Maintained -F: Documentation/keys.txt +F: Documentation/security/keys.txt F: include/linux/key.h F: include/linux/key-type.h F: include/keys/ @@ -3717,7 +3717,7 @@ M: Mimi Zohar L: linux-security-module@vger.kernel.org L: keyrings@linux-nfs.org S: Supported -F: Documentation/keys-trusted-encrypted.txt +F: Documentation/security/keys-trusted-encrypted.txt F: include/keys/trusted-type.h F: security/keys/trusted.c F: security/keys/trusted.h @@ -3728,7 +3728,7 @@ M: David Safford L: linux-security-module@vger.kernel.org L: keyrings@linux-nfs.org S: Supported -F: Documentation/keys-trusted-encrypted.txt +F: Documentation/security/keys-trusted-encrypted.txt F: include/keys/encrypted-type.h F: security/keys/encrypted.c F: security/keys/encrypted.h diff --git a/include/linux/cred.h b/include/linux/cred.h index be16b61283cc..82607992f308 100644 --- a/include/linux/cred.h +++ b/include/linux/cred.h @@ -1,4 +1,4 @@ -/* Credentials management - see Documentation/credentials.txt +/* Credentials management - see Documentation/security/credentials.txt * * Copyright (C) 2008 Red Hat, Inc. All Rights Reserved. * Written by David Howells (dhowells@redhat.com) diff --git a/include/linux/key.h b/include/linux/key.h index b2bb01719561..303982a69933 100644 --- a/include/linux/key.h +++ b/include/linux/key.h @@ -9,7 +9,7 @@ * 2 of the License, or (at your option) any later version. * * - * See Documentation/keys.txt for information on keys/keyrings. + * See Documentation/security/keys.txt for information on keys/keyrings. */ #ifndef _LINUX_KEY_H diff --git a/kernel/cred.c b/kernel/cred.c index 8093c16b84b1..004e3679624d 100644 --- a/kernel/cred.c +++ b/kernel/cred.c @@ -1,4 +1,4 @@ -/* Task credentials management - see Documentation/credentials.txt +/* Task credentials management - see Documentation/security/credentials.txt * * Copyright (C) 2008 Red Hat, Inc. All Rights Reserved. * Written by David Howells (dhowells@redhat.com) diff --git a/scripts/selinux/README b/scripts/selinux/README index a936315ba2c8..4d020ecb7524 100644 --- a/scripts/selinux/README +++ b/scripts/selinux/README @@ -1,2 +1,2 @@ -Please see Documentation/SELinux.txt for information on +Please see Documentation/security/SELinux.txt for information on installing a dummy SELinux policy. diff --git a/security/apparmor/match.c b/security/apparmor/match.c index 06d764ccbbe5..94de6b4907c8 100644 --- a/security/apparmor/match.c +++ b/security/apparmor/match.c @@ -194,7 +194,7 @@ void aa_dfa_free_kref(struct kref *kref) * @flags: flags controlling what type of accept tables are acceptable * * Unpack a dfa that has been serialized. To find information on the dfa - * format look in Documentation/apparmor.txt + * format look in Documentation/security/apparmor.txt * Assumes the dfa @blob stream has been aligned on a 8 byte boundary * * Returns: an unpacked dfa ready for matching or ERR_PTR on failure diff --git a/security/apparmor/policy_unpack.c b/security/apparmor/policy_unpack.c index e33aaf7e5744..d6d9a57b5652 100644 --- a/security/apparmor/policy_unpack.c +++ b/security/apparmor/policy_unpack.c @@ -12,8 +12,8 @@ * published by the Free Software Foundation, version 2 of the * License. * - * AppArmor uses a serialized binary format for loading policy. - * To find policy format documentation look in Documentation/apparmor.txt + * AppArmor uses a serialized binary format for loading policy. To find + * policy format documentation look in Documentation/security/apparmor.txt * All policy is validated before it is used. */ diff --git a/security/keys/encrypted.c b/security/keys/encrypted.c index 69907a58a683..b1cba5bf0a5e 100644 --- a/security/keys/encrypted.c +++ b/security/keys/encrypted.c @@ -8,7 +8,7 @@ * it under the terms of the GNU General Public License as published by * the Free Software Foundation, version 2 of the License. * - * See Documentation/keys-trusted-encrypted.txt + * See Documentation/security/keys-trusted-encrypted.txt */ #include diff --git a/security/keys/request_key.c b/security/keys/request_key.c index df3c0417ee40..d41cc153a313 100644 --- a/security/keys/request_key.c +++ b/security/keys/request_key.c @@ -8,7 +8,7 @@ * as published by the Free Software Foundation; either version * 2 of the License, or (at your option) any later version. * - * See Documentation/keys-request-key.txt + * See Documentation/security/keys-request-key.txt */ #include diff --git a/security/keys/request_key_auth.c b/security/keys/request_key_auth.c index 68164031a74e..3c0cfdec6e37 100644 --- a/security/keys/request_key_auth.c +++ b/security/keys/request_key_auth.c @@ -8,7 +8,7 @@ * as published by the Free Software Foundation; either version * 2 of the License, or (at your option) any later version. * - * See Documentation/keys-request-key.txt + * See Documentation/security/keys-request-key.txt */ #include diff --git a/security/keys/trusted.c b/security/keys/trusted.c index c99b9368368c..0c33e2ea1f3c 100644 --- a/security/keys/trusted.c +++ b/security/keys/trusted.c @@ -8,7 +8,7 @@ * it under the terms of the GNU General Public License as published by * the Free Software Foundation, version 2 of the License. * - * See Documentation/keys-trusted-encrypted.txt + * See Documentation/security/keys-trusted-encrypted.txt */ #include -- cgit v1.2.3-71-gd317 From 2626e674021c28250874a68f47b0f4759fcf63db Mon Sep 17 00:00:00 2001 From: Eduardo Silva Date: Thu, 19 May 2011 08:37:01 -0400 Subject: gconfig: enable rules hint for main treeviews Due to the large amount of rows in the treeviews, is difficult to match columns with rows, setting the rules hint to 'true' allows the treeview to alternate background colors in the rows making the data more readable. Signed-off-by: Eduardo Silva Tested-by: Randy Dunlap Signed-off-by: Michal Marek --- scripts/kconfig/gconf.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'scripts') diff --git a/scripts/kconfig/gconf.c b/scripts/kconfig/gconf.c index 455896164d72..0c8db7d63c20 100644 --- a/scripts/kconfig/gconf.c +++ b/scripts/kconfig/gconf.c @@ -253,7 +253,7 @@ void init_left_tree(void) gtk_tree_view_set_model(view, model1); gtk_tree_view_set_headers_visible(view, TRUE); - gtk_tree_view_set_rules_hint(view, FALSE); + gtk_tree_view_set_rules_hint(view, TRUE); column = gtk_tree_view_column_new(); gtk_tree_view_append_column(view, column); @@ -298,7 +298,7 @@ void init_right_tree(void) gtk_tree_view_set_model(view, model2); gtk_tree_view_set_headers_visible(view, TRUE); - gtk_tree_view_set_rules_hint(view, FALSE); + gtk_tree_view_set_rules_hint(view, TRUE); column = gtk_tree_view_column_new(); gtk_tree_view_append_column(view, column); -- cgit v1.2.3-71-gd317 From 6ef3d36eee2a5593e31f9f77b4aa992024838ff7 Mon Sep 17 00:00:00 2001 From: Eduardo Silva Date: Thu, 19 May 2011 08:38:25 -0400 Subject: gconfig: Hide unused left treeview when start up the interface When the gconfig program starts in full mode view, it shows the left treeview which belongs to the 'split mode view'. The patch fix this visual issue. Signed-off-by: Eduardo Silva Signed-off-by: Michal Marek --- scripts/kconfig/gconf.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) (limited to 'scripts') diff --git a/scripts/kconfig/gconf.c b/scripts/kconfig/gconf.c index 0c8db7d63c20..a11d5f7b9eeb 100644 --- a/scripts/kconfig/gconf.c +++ b/scripts/kconfig/gconf.c @@ -756,7 +756,6 @@ void on_load_clicked(GtkButton * button, gpointer user_data) void on_single_clicked(GtkButton * button, gpointer user_data) { view_mode = SINGLE_VIEW; - gtk_paned_set_position(GTK_PANED(hpaned), 0); gtk_widget_hide(tree1_w); current = &rootmenu; display_tree_part(); @@ -782,7 +781,6 @@ void on_split_clicked(GtkButton * button, gpointer user_data) void on_full_clicked(GtkButton * button, gpointer user_data) { view_mode = FULL_VIEW; - gtk_paned_set_position(GTK_PANED(hpaned), 0); gtk_widget_hide(tree1_w); if (tree2) gtk_tree_store_clear(tree2); @@ -1444,6 +1442,12 @@ static void display_tree(struct menu *menu) if (((menu != &rootmenu) && !(menu->flags & MENU_ROOT)) || (view_mode == FULL_VIEW) || (view_mode == SPLIT_VIEW))*/ + + /* Change paned position if the view is not in 'split mode' */ + if (view_mode == SINGLE_VIEW || view_mode == FULL_VIEW) { + gtk_paned_set_position(GTK_PANED(hpaned), 0); + } + if (((view_mode == SINGLE_VIEW) && (menu->flags & MENU_ROOT)) || (view_mode == FULL_VIEW) || (view_mode == SPLIT_VIEW)) { -- cgit v1.2.3-71-gd317 From de7b0b4110795be914e6cafdfec4276b2618cc78 Mon Sep 17 00:00:00 2001 From: Jim Cromie Date: Mon, 23 May 2011 12:44:55 -0600 Subject: export_report: do collectcfiles work in perl itself Avoid spawning a shell pipeline doing cat, grep, sed, and do it all inside perl. The <*.c> globbing construct works at least as far back as 5.8.9 Note that this is not just an optimization; the sed command in the pipeline was unterminated, due to lack of escape on the end-of-line (\$) in the regex, resulting in this: $ perl ../linux-2.6/scripts/export_report.pl > /dev/null sed: -e expression #1, char 5: unterminated `s' command sh: .mod.c/: not found Comments on an earlier patch sought an all-perl implementation. Signed-off-by: Jim Cromie cc: Michal Marek , cc: linux-kbuild@vger.kernel.org cc: Arnaud Lacombe lacombar@gmail.com cc: Stephen Hemminger shemminger@vyatta.com Signed-off-by: Michal Marek --- scripts/export_report.pl | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) (limited to 'scripts') diff --git a/scripts/export_report.pl b/scripts/export_report.pl index 04dce7c15f83..f97899c87923 100644 --- a/scripts/export_report.pl +++ b/scripts/export_report.pl @@ -49,8 +49,14 @@ sub usage { } sub collectcfiles { - my @file - = `cat .tmp_versions/*.mod | grep '.*\.ko\$' | sed s/\.ko$/.mod.c/`; + my @file; + while (<.tmp_versions/*.mod>) { + open my $fh, '<', $_ or die "cannot open $_: $!\n"; + push (@file, + grep s/\.ko/.mod.c/, # change the suffix + grep m/.+\.ko/, # find the .ko path + <$fh>); # lines in opened file + } chomp @file; return @file; } -- cgit v1.2.3-71-gd317 From bdabc7a345db97b3839c2c3deef40023cf8017ef Mon Sep 17 00:00:00 2001 From: Jim Cromie Date: Mon, 23 May 2011 12:44:56 -0600 Subject: export_report: sort SECTION 2 output Sort SECTION 2 modules by name. Within those module listings, sort the symbol providers by name, and remove the count, as it is misleading; its the kernel-wide count of uses of that symbol, not the count pertaining to the module being outlined. (this can be seen by grepping the output for a single symbol). The count is still used to sort the symbols. Signed-off-by: Jim Cromie Signed-off-by: Michal Marek --- scripts/export_report.pl | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) (limited to 'scripts') diff --git a/scripts/export_report.pl b/scripts/export_report.pl index f97899c87923..48398a19fbbc 100644 --- a/scripts/export_report.pl +++ b/scripts/export_report.pl @@ -25,11 +25,12 @@ sub alphabetically { sub print_depends_on { my ($href) = @_; print "\n"; - while (my ($mod, $list) = each %$href) { + for my $mod (sort keys %$href) { + my $list = $href->{$mod}; print "\t$mod:\n"; foreach my $sym (sort numerically @{$list}) { my ($symbol, $no) = split /\s+/, $sym; - printf("\t\t%-25s\t%-25d\n", $symbol, $no); + printf("\t\t%-25s\n", $symbol); } print "\n"; } @@ -166,7 +167,8 @@ modules. Each module lists the modules, and the symbols from that module that it uses. Each listed symbol reports the number of modules using it\n"); print "~"x80 , "\n"; -while (my ($thismod, $list) = each %MODULE) { +for my $thismod (sort keys %MODULE) { + my $list = $MODULE{$thismod}; my %depends; $thismod =~ s/\.mod\.c/.ko/; print "\t\t\t$thismod\n"; -- cgit v1.2.3-71-gd317 From ca995cbf77f3df599b7e751c2d08d90787c65c45 Mon Sep 17 00:00:00 2001 From: Jim Cromie Date: Mon, 23 May 2011 12:44:57 -0600 Subject: export_report: use warn() to issue WARNING, so they go to stderr Also count CONFIG_MODVERSIONS warnings, and print a NOTE at start of SECTION 2 if any were issued. Section 2 will be empty if the build is lacking this CONFIG_ item, and user may have missed the warnings, as they're off screen. Signed-off-by: Jim Cromie Signed-off-by: Michal Marek --- scripts/export_report.pl | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) (limited to 'scripts') diff --git a/scripts/export_report.pl b/scripts/export_report.pl index 48398a19fbbc..8f79b701de87 100644 --- a/scripts/export_report.pl +++ b/scripts/export_report.pl @@ -102,6 +102,8 @@ close($module_symvers); # # collect the usage count of each symbol. # +my $modversion_warnings = 0; + foreach my $thismod (@allcfiles) { my $module; @@ -132,7 +134,8 @@ foreach my $thismod (@allcfiles) { } } if ($state != 2) { - print "WARNING:$thismod is not built with CONFIG_MODVERSION enabled\n"; + warn "WARNING:$thismod is not built with CONFIG_MODVERSIONS enabled\n"; + $modversion_warnings++; } close($module); } @@ -166,6 +169,9 @@ printf("SECTION 2:\n\tThis section reports export-symbol-usage of in-kernel modules. Each module lists the modules, and the symbols from that module that it uses. Each listed symbol reports the number of modules using it\n"); +print "\nNOTE: Got $modversion_warnings CONFIG_MODVERSIONS warnings\n\n" + if $modversion_warnings; + print "~"x80 , "\n"; for my $thismod (sort keys %MODULE) { my $list = $MODULE{$thismod}; -- cgit v1.2.3-71-gd317 From bdebd4892e05cc9068659f25af33c6b322034eb2 Mon Sep 17 00:00:00 2001 From: Arnaud Lacombe Date: Sun, 15 May 2011 23:22:56 -0400 Subject: kconfig: do not record timestamp in .config Signed-off-by: Arnaud Lacombe Signed-off-by: Michal Marek --- Documentation/kbuild/kconfig.txt | 5 ----- scripts/kconfig/confdata.c | 12 +----------- 2 files changed, 1 insertion(+), 16 deletions(-) (limited to 'scripts') diff --git a/Documentation/kbuild/kconfig.txt b/Documentation/kbuild/kconfig.txt index cca46b1a0f6c..c313d71324b4 100644 --- a/Documentation/kbuild/kconfig.txt +++ b/Documentation/kbuild/kconfig.txt @@ -48,11 +48,6 @@ KCONFIG_OVERWRITECONFIG If you set KCONFIG_OVERWRITECONFIG in the environment, Kconfig will not break symlinks when .config is a symlink to somewhere else. -KCONFIG_NOTIMESTAMP --------------------------------------------------- -If this environment variable exists and is non-null, the timestamp line -in generated .config files is omitted. - ______________________________________________________________________ Environment variables for '{allyes/allmod/allno/rand}config' diff --git a/scripts/kconfig/confdata.c b/scripts/kconfig/confdata.c index 834eecb010ba..2bafd9a7c8da 100644 --- a/scripts/kconfig/confdata.c +++ b/scripts/kconfig/confdata.c @@ -560,8 +560,6 @@ int conf_write(const char *name) const char *basename; const char *str; char dirname[PATH_MAX+1], tmpname[PATH_MAX+1], newname[PATH_MAX+1]; - time_t now; - int use_timestamp = 1; char *env; dirname[0] = 0; @@ -598,19 +596,11 @@ int conf_write(const char *name) if (!out) return 1; - time(&now); - env = getenv("KCONFIG_NOTIMESTAMP"); - if (env && *env) - use_timestamp = 0; - fprintf(out, _("#\n" "# Automatically generated make config: don't edit\n" "# %s\n" - "%s%s" "#\n"), - rootmenu.prompt->text, - use_timestamp ? "# " : "", - use_timestamp ? ctime(&now) : ""); + rootmenu.prompt->text); if (!conf_get_changed()) sym_clear_all_valid(); -- cgit v1.2.3-71-gd317 From 857c7e438769c0f251092a20b587d6e743ee489d Mon Sep 17 00:00:00 2001 From: Michal Marek Date: Thu, 5 May 2011 00:37:13 +0200 Subject: rpm-pkg: Fix when current directory is a symlink The better fix would be to stop using the parent directory (principle of least surprise), but as long as we use it, use it consistently. Signed-off-by: Michal Marek --- scripts/package/Makefile | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'scripts') diff --git a/scripts/package/Makefile b/scripts/package/Makefile index 1b7eaea83123..006960ebbce9 100644 --- a/scripts/package/Makefile +++ b/scripts/package/Makefile @@ -28,7 +28,7 @@ RPM := $(shell if [ -x "/usr/bin/rpmbuild" ]; then echo rpmbuild; \ # Remove hyphens since they have special meaning in RPM filenames KERNELPATH := kernel-$(subst -,_,$(KERNELRELEASE)) MKSPEC := $(srctree)/scripts/package/mkspec -PREV := set -e; cd ..; +PREV := set -e; cd -P ..; # rpm-pkg # --------------------------------------------------------------------------- -- cgit v1.2.3-71-gd317 From 0bd41dfc9fbbcf174d5336c1c9fc5ba917519761 Mon Sep 17 00:00:00 2001 From: Arun Sharma Date: Tue, 17 May 2011 10:36:16 -0700 Subject: kbuild: Create a kernel-headers RPM To compile binaries which depend on new kernel interfaces, we need a kernel-headers RPM Signed-off-by: Arun Sharma Signed-off-by: Michal Marek --- scripts/package/mkspec | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) (limited to 'scripts') diff --git a/scripts/package/mkspec b/scripts/package/mkspec index ed8b6a8b4b8e..4bf17ddf7c7f 100755 --- a/scripts/package/mkspec +++ b/scripts/package/mkspec @@ -47,6 +47,18 @@ echo "" echo "%description" echo "The Linux Kernel, the operating system core itself" echo "" +echo "%package headers" +echo "Summary: Header files for the Linux kernel for use by glibc" +echo "Group: Development/System" +echo "Obsoletes: kernel-headers" +echo "Provides: kernel-headers = %{version}" +echo "%description headers" +echo "Kernel-headers includes the C header files that specify the interface" +echo "between the Linux kernel and userspace libraries and programs. The" +echo "header files define structures and constants that are needed for" +echo "building most standard programs and are also needed for rebuilding the" +echo "glibc package." +echo "" if ! $PREBUILT; then echo "%prep" @@ -83,6 +95,7 @@ echo 'cp $KBUILD_IMAGE $RPM_BUILD_ROOT'"/boot/vmlinuz-$KERNELRELEASE" echo "%endif" echo "%endif" +echo 'make %{?_smp_mflags} INSTALL_HDR_PATH=$RPM_BUILD_ROOT/usr headers_install' echo 'cp System.map $RPM_BUILD_ROOT'"/boot/System.map-$KERNELRELEASE" echo 'cp .config $RPM_BUILD_ROOT'"/boot/config-$KERNELRELEASE" @@ -105,3 +118,7 @@ echo "/lib/modules/$KERNELRELEASE" echo "/lib/firmware" echo "/boot/*" echo "" +echo "%files headers" +echo '%defattr (-, root, root)' +echo "/usr/include" +echo "" -- cgit v1.2.3-71-gd317 From d49e46875c11a09e80e76c66db90710369b8fe12 Mon Sep 17 00:00:00 2001 From: Arnaud Lacombe Date: Tue, 24 May 2011 14:16:18 -0400 Subject: xconfig: merge code path to conf_write() Avoid to have multiple path saving the config. This fixes an error check miss when the window is being closed and the user requested the config to be written. Reported-by: Hiromu Yakura Pointed-out-by: Michal Marek Signed-off-by: Michal Marek --- scripts/kconfig/qconf.cc | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) (limited to 'scripts') diff --git a/scripts/kconfig/qconf.cc b/scripts/kconfig/qconf.cc index 06dd2e33581d..c2796b866f8f 100644 --- a/scripts/kconfig/qconf.cc +++ b/scripts/kconfig/qconf.cc @@ -1489,8 +1489,7 @@ void ConfigMainWindow::saveConfigAs(void) QString s = Q3FileDialog::getSaveFileName(conf_get_configname(), NULL, this); if (s.isNull()) return; - if (conf_write(QFile::encodeName(s))) - QMessageBox::information(this, "qconf", _("Unable to save configuration!")); + saveConfig(); } void ConfigMainWindow::searchConfig(void) @@ -1643,7 +1642,7 @@ void ConfigMainWindow::closeEvent(QCloseEvent* e) mb.setButtonText(QMessageBox::Cancel, _("Cancel Exit")); switch (mb.exec()) { case QMessageBox::Yes: - conf_write(NULL); + saveConfig(); case QMessageBox::No: e->accept(); break; -- cgit v1.2.3-71-gd317 From 428e2fdc4ecee2312829e97549f99c12312f4faf Mon Sep 17 00:00:00 2001 From: Joe Perches Date: Tue, 24 May 2011 17:13:39 -0700 Subject: checkpatch: add check for line continuations in quoted strings Add a warning for unterminated quoted strings with line continuations as these frequently add unwanted whitespace. Signed-off-by: Joe Perches Cc: Andy Whitcroft Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- scripts/checkpatch.pl | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'scripts') diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl index d8670810db65..5c9672951077 100755 --- a/scripts/checkpatch.pl +++ b/scripts/checkpatch.pl @@ -2748,6 +2748,11 @@ sub process { WARN("sizeof(& should be avoided\n" . $herecurr); } +# check for line continuations in quoted strings with odd counts of " + if ($rawline =~ /\\$/ && $rawline =~ tr/"/"/ % 2) { + WARN("Avoid line continuations in quoted strings\n" . $herecurr); + } + # check for new externs in .c files. if ($realfile =~ /\.c$/ && defined $stat && $stat =~ /^.\s*(?:extern\s+)?$Type\s+($Ident)(\s*)\(/s) -- cgit v1.2.3-71-gd317 From b05317221b7607ba61ee921c31867ed08912aa46 Mon Sep 17 00:00:00 2001 From: Joe Perches Date: Tue, 24 May 2011 17:13:40 -0700 Subject: checkpatch: add _ and MODULE_ to 80 column exceptions Many module or file local logging functions use specific prefixes other than pr|dev|netdev. Allow all forms like foo_printk and foo_err to be longer than 80 columns. Also allow MODULE_ declarations to be longer than 80 columns. Signed-off-by: Joe Perches Cc: Andy Whitcroft Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- scripts/checkpatch.pl | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'scripts') diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl index 5c9672951077..0e158667d478 100755 --- a/scripts/checkpatch.pl +++ b/scripts/checkpatch.pl @@ -210,10 +210,10 @@ our $typeTypedefs = qr{(?x: our $logFunctions = qr{(?x: printk| - pr_(debug|dbg|vdbg|devel|info|warning|err|notice|alert|crit|emerg|cont)| - (dev|netdev|netif)_(printk|dbg|vdbg|info|warn|err|notice|alert|crit|emerg|WARN)| + [a-z]+_(emerg|alert|crit|err|warning|warn|notice|info|debug|dbg|vdbg|devel|cont|WARN)| WARN| - panic + panic| + MODULE_[A-Z_]+ )}; our @typeList = ( -- cgit v1.2.3-71-gd317 From 0fccc6221821e07366aa44bca112c4edb6d04dd7 Mon Sep 17 00:00:00 2001 From: Joe Perches Date: Tue, 24 May 2011 17:13:41 -0700 Subject: checkpatch: fix defect in printk(KERN_ 80 column exceptions Currently, printk lines with a only KERN_PREFIX and a quoted string without a comma or close paren that exceed 80 columns are flagged with a warning. ie: printk(KERN_WARNING "some long string that extends beond 80 cols..." "and is continued on another line\n"); Allow this form instead of emitting a warning. Signed-off-by: Joe Perches Cc: Andy Whitcroft Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- scripts/checkpatch.pl | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'scripts') diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl index 0e158667d478..8657f99bfb2b 100755 --- a/scripts/checkpatch.pl +++ b/scripts/checkpatch.pl @@ -1462,7 +1462,7 @@ sub process { #80 column limit if ($line =~ /^\+/ && $prevrawline !~ /\/\*\*/ && $rawline !~ /^.\s*\*\s*\@$Ident\s/ && - !($line =~ /^\+\s*$logFunctions\s*\(\s*(?:(KERN_\S+\s*|[^"]*))?"[X\t]*"\s*(?:,|\)\s*;)\s*$/ || + !($line =~ /^\+\s*$logFunctions\s*\(\s*(?:(KERN_\S+\s*|[^"]*))?"[X\t]*"\s*(?:|,|\)\s*;)\s*$/ || $line =~ /^\+\s*"[^"]*"\s*(?:\s*|,|\)\s*;)\s*$/) && $length > 80) { -- cgit v1.2.3-71-gd317 From 50d6828e898590fc5d038810334695380baa1c78 Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Thu, 19 May 2011 14:41:17 -0400 Subject: scripts/tags.sh: Fix ctags for DEFINE_EVENT() The regex to handle DEFINE_EVENT() should not be the same as the TRACE_EVENT() as the first parameter in DEFINE_EVENT is the template name, not the event name. We need the second parameter as that is what the trace_... will use. Tested-by: Peter Zijlstra Signed-off-by: Steven Rostedt --- scripts/tags.sh | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'scripts') diff --git a/scripts/tags.sh b/scripts/tags.sh index bd6185d529cf..33b53cab5dbf 100755 --- a/scripts/tags.sh +++ b/scripts/tags.sh @@ -132,7 +132,7 @@ exuberant() --regex-asm='/^ENTRY\(([^)]*)\).*/\1/' \ --regex-c='/^SYSCALL_DEFINE[[:digit:]]?\(([^,)]*).*/sys_\1/' \ --regex-c++='/^TRACE_EVENT\(([^,)]*).*/trace_\1/' \ - --regex-c++='/^DEFINE_EVENT\(([^,)]*).*/trace_\1/' + --regex-c++='/^DEFINE_EVENT\([^,)]*, *([^,)]*).*/trace_\1/' all_kconfigs | xargs $1 -a \ --langdef=kconfig --language-force=kconfig \ -- cgit v1.2.3-71-gd317 From 4d7a2fa876d1a615649761dc465708d0a062249a Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Thu, 19 May 2011 14:43:57 -0400 Subject: scripts/tags.sh: Add magic for trace-events for etags too Seems that Peter Zijlstra treats us emacs users as second class citizens and the commit: commit 15664125f7cadcb6d725cb2d9b90f9715397848d Author: Peter Zijlstra scripts/tags.sh: Add magic for trace-events only updated ctags (for vim) and did not do the work to let us lowly emacs users benefit from such a change. Cc: Peter Zijlstra Signed-off-by: Steven Rostedt --- scripts/tags.sh | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'scripts') diff --git a/scripts/tags.sh b/scripts/tags.sh index 33b53cab5dbf..75c5d24f1993 100755 --- a/scripts/tags.sh +++ b/scripts/tags.sh @@ -152,7 +152,9 @@ emacs() { all_sources | xargs $1 -a \ --regex='/^ENTRY(\([^)]*\)).*/\1/' \ - --regex='/^SYSCALL_DEFINE[0-9]?(\([^,)]*\).*/sys_\1/' + --regex='/^SYSCALL_DEFINE[0-9]?(\([^,)]*\).*/sys_\1/' \ + --regex='/^TRACE_EVENT(\([^,)]*\).*/trace_\1/' \ + --regex='/^DEFINE_EVENT([^,)]*, *\([^,)]*\).*/trace_\1/' all_kconfigs | xargs $1 -a \ --regex='/^[ \t]*\(\(menu\)*config\)[ \t]+\([a-zA-Z0-9_]+\)/\3/' -- cgit v1.2.3-71-gd317 From 9905ce8ad7b79dddd23c7b4753d0b2cdb65bde3c Mon Sep 17 00:00:00 2001 From: Rabin Vincent Date: Wed, 11 May 2011 22:53:51 +0530 Subject: ftrace/recordmcount: Avoid STT_FUNC symbols as base on ARM While find_secsym_ndx often finds the unamed local STT_SECTION, if a section has only one function in it, the ARM toolchain generates the STT_FUNC symbol before the STT_SECTION, and recordmcount finds this instead. This is problematic on ARM because in ARM ELFs, "if a [STT_FUNC] symbol addresses a Thumb instruction, its value is the address of the instruction with bit zero set (in a relocatable object, the section offset with bit zero set)". This leads to incorrect mcount addresses being recorded. Fix this by not using STT_FUNC symbols as the base on ARM. Signed-off-by: Rabin Vincent Link: http://lkml.kernel.org/r/1305134631-31617-1-git-send-email-rabin@rab.in Signed-off-by: Steven Rostedt --- scripts/recordmcount.h | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'scripts') diff --git a/scripts/recordmcount.h b/scripts/recordmcount.h index 4be60364a405..f40a6af6bf40 100644 --- a/scripts/recordmcount.h +++ b/scripts/recordmcount.h @@ -43,6 +43,7 @@ #undef ELF_R_INFO #undef Elf_r_info #undef ELF_ST_BIND +#undef ELF_ST_TYPE #undef fn_ELF_R_SYM #undef fn_ELF_R_INFO #undef uint_t @@ -76,6 +77,7 @@ # define ELF_R_INFO ELF64_R_INFO # define Elf_r_info Elf64_r_info # define ELF_ST_BIND ELF64_ST_BIND +# define ELF_ST_TYPE ELF64_ST_TYPE # define fn_ELF_R_SYM fn_ELF64_R_SYM # define fn_ELF_R_INFO fn_ELF64_R_INFO # define uint_t uint64_t @@ -108,6 +110,7 @@ # define ELF_R_INFO ELF32_R_INFO # define Elf_r_info Elf32_r_info # define ELF_ST_BIND ELF32_ST_BIND +# define ELF_ST_TYPE ELF32_ST_TYPE # define fn_ELF_R_SYM fn_ELF32_R_SYM # define fn_ELF_R_INFO fn_ELF32_R_INFO # define uint_t uint32_t @@ -427,6 +430,11 @@ static unsigned find_secsym_ndx(unsigned const txtndx, if (txtndx == w2(symp->st_shndx) /* avoid STB_WEAK */ && (STB_LOCAL == st_bind || STB_GLOBAL == st_bind)) { + /* function symbols on ARM have quirks, avoid them */ + if (w2(ehdr->e_machine) == EM_ARM + && ELF_ST_TYPE(symp->st_info) == STT_FUNC) + continue; + *recvalp = _w(symp->st_value); return symp - sym0; } -- cgit v1.2.3-71-gd317