cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
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ubifs-media.h (25382B)


      1/* SPDX-License-Identifier: GPL-2.0-only */
      2/*
      3 * This file is part of UBIFS.
      4 *
      5 * Copyright (C) 2006-2008 Nokia Corporation.
      6 *
      7 * Authors: Artem Bityutskiy (Битюцкий Артём)
      8 *          Adrian Hunter
      9 */
     10
     11/*
     12 * This file describes UBIFS on-flash format and contains definitions of all the
     13 * relevant data structures and constants.
     14 *
     15 * All UBIFS on-flash objects are stored in the form of nodes. All nodes start
     16 * with the UBIFS node magic number and have the same common header. Nodes
     17 * always sit at 8-byte aligned positions on the media and node header sizes are
     18 * also 8-byte aligned (except for the indexing node and the padding node).
     19 */
     20
     21#ifndef __UBIFS_MEDIA_H__
     22#define __UBIFS_MEDIA_H__
     23
     24/* UBIFS node magic number (must not have the padding byte first or last) */
     25#define UBIFS_NODE_MAGIC  0x06101831
     26
     27/*
     28 * UBIFS on-flash format version. This version is increased when the on-flash
     29 * format is changing. If this happens, UBIFS is will support older versions as
     30 * well. But older UBIFS code will not support newer formats. Format changes
     31 * will be rare and only when absolutely necessary, e.g. to fix a bug or to add
     32 * a new feature.
     33 *
     34 * UBIFS went into mainline kernel with format version 4. The older formats
     35 * were development formats.
     36 */
     37#define UBIFS_FORMAT_VERSION 5
     38
     39/*
     40 * Read-only compatibility version. If the UBIFS format is changed, older UBIFS
     41 * implementations will not be able to mount newer formats in read-write mode.
     42 * However, depending on the change, it may be possible to mount newer formats
     43 * in R/O mode. This is indicated by the R/O compatibility version which is
     44 * stored in the super-block.
     45 *
     46 * This is needed to support boot-loaders which only need R/O mounting. With
     47 * this flag it is possible to do UBIFS format changes without a need to update
     48 * boot-loaders.
     49 */
     50#define UBIFS_RO_COMPAT_VERSION 0
     51
     52/* Minimum logical eraseblock size in bytes */
     53#define UBIFS_MIN_LEB_SZ (15*1024)
     54
     55/* Initial CRC32 value used when calculating CRC checksums */
     56#define UBIFS_CRC32_INIT 0xFFFFFFFFU
     57
     58/*
     59 * UBIFS does not try to compress data if its length is less than the below
     60 * constant.
     61 */
     62#define UBIFS_MIN_COMPR_LEN 128
     63
     64/*
     65 * If compressed data length is less than %UBIFS_MIN_COMPRESS_DIFF bytes
     66 * shorter than uncompressed data length, UBIFS prefers to leave this data
     67 * node uncompress, because it'll be read faster.
     68 */
     69#define UBIFS_MIN_COMPRESS_DIFF 64
     70
     71/* Root inode number */
     72#define UBIFS_ROOT_INO 1
     73
     74/* Lowest inode number used for regular inodes (not UBIFS-only internal ones) */
     75#define UBIFS_FIRST_INO 64
     76
     77/*
     78 * Maximum file name and extended attribute length (must be a multiple of 8,
     79 * minus 1).
     80 */
     81#define UBIFS_MAX_NLEN 255
     82
     83/* Maximum number of data journal heads */
     84#define UBIFS_MAX_JHEADS 1
     85
     86/*
     87 * Size of UBIFS data block. Note, UBIFS is not a block oriented file-system,
     88 * which means that it does not treat the underlying media as consisting of
     89 * blocks like in case of hard drives. Do not be confused. UBIFS block is just
     90 * the maximum amount of data which one data node can have or which can be
     91 * attached to an inode node.
     92 */
     93#define UBIFS_BLOCK_SIZE  4096
     94#define UBIFS_BLOCK_SHIFT 12
     95
     96/* UBIFS padding byte pattern (must not be first or last byte of node magic) */
     97#define UBIFS_PADDING_BYTE 0xCE
     98
     99/* Maximum possible key length */
    100#define UBIFS_MAX_KEY_LEN 16
    101
    102/* Key length ("simple" format) */
    103#define UBIFS_SK_LEN 8
    104
    105/* Minimum index tree fanout */
    106#define UBIFS_MIN_FANOUT 3
    107
    108/* Maximum number of levels in UBIFS indexing B-tree */
    109#define UBIFS_MAX_LEVELS 512
    110
    111/* Maximum amount of data attached to an inode in bytes */
    112#define UBIFS_MAX_INO_DATA UBIFS_BLOCK_SIZE
    113
    114/* LEB Properties Tree fanout (must be power of 2) and fanout shift */
    115#define UBIFS_LPT_FANOUT 4
    116#define UBIFS_LPT_FANOUT_SHIFT 2
    117
    118/* LEB Properties Tree bit field sizes */
    119#define UBIFS_LPT_CRC_BITS 16
    120#define UBIFS_LPT_CRC_BYTES 2
    121#define UBIFS_LPT_TYPE_BITS 4
    122
    123/* The key is always at the same position in all keyed nodes */
    124#define UBIFS_KEY_OFFSET offsetof(struct ubifs_ino_node, key)
    125
    126/* Garbage collector journal head number */
    127#define UBIFS_GC_HEAD   0
    128/* Base journal head number */
    129#define UBIFS_BASE_HEAD 1
    130/* Data journal head number */
    131#define UBIFS_DATA_HEAD 2
    132
    133/*
    134 * LEB Properties Tree node types.
    135 *
    136 * UBIFS_LPT_PNODE: LPT leaf node (contains LEB properties)
    137 * UBIFS_LPT_NNODE: LPT internal node
    138 * UBIFS_LPT_LTAB: LPT's own lprops table
    139 * UBIFS_LPT_LSAVE: LPT's save table (big model only)
    140 * UBIFS_LPT_NODE_CNT: count of LPT node types
    141 * UBIFS_LPT_NOT_A_NODE: all ones (15 for 4 bits) is never a valid node type
    142 */
    143enum {
    144	UBIFS_LPT_PNODE,
    145	UBIFS_LPT_NNODE,
    146	UBIFS_LPT_LTAB,
    147	UBIFS_LPT_LSAVE,
    148	UBIFS_LPT_NODE_CNT,
    149	UBIFS_LPT_NOT_A_NODE = (1 << UBIFS_LPT_TYPE_BITS) - 1,
    150};
    151
    152/*
    153 * UBIFS inode types.
    154 *
    155 * UBIFS_ITYPE_REG: regular file
    156 * UBIFS_ITYPE_DIR: directory
    157 * UBIFS_ITYPE_LNK: soft link
    158 * UBIFS_ITYPE_BLK: block device node
    159 * UBIFS_ITYPE_CHR: character device node
    160 * UBIFS_ITYPE_FIFO: fifo
    161 * UBIFS_ITYPE_SOCK: socket
    162 * UBIFS_ITYPES_CNT: count of supported file types
    163 */
    164enum {
    165	UBIFS_ITYPE_REG,
    166	UBIFS_ITYPE_DIR,
    167	UBIFS_ITYPE_LNK,
    168	UBIFS_ITYPE_BLK,
    169	UBIFS_ITYPE_CHR,
    170	UBIFS_ITYPE_FIFO,
    171	UBIFS_ITYPE_SOCK,
    172	UBIFS_ITYPES_CNT,
    173};
    174
    175/*
    176 * Supported key hash functions.
    177 *
    178 * UBIFS_KEY_HASH_R5: R5 hash
    179 * UBIFS_KEY_HASH_TEST: test hash which just returns first 4 bytes of the name
    180 */
    181enum {
    182	UBIFS_KEY_HASH_R5,
    183	UBIFS_KEY_HASH_TEST,
    184};
    185
    186/*
    187 * Supported key formats.
    188 *
    189 * UBIFS_SIMPLE_KEY_FMT: simple key format
    190 */
    191enum {
    192	UBIFS_SIMPLE_KEY_FMT,
    193};
    194
    195/*
    196 * The simple key format uses 29 bits for storing UBIFS block number and hash
    197 * value.
    198 */
    199#define UBIFS_S_KEY_BLOCK_BITS 29
    200#define UBIFS_S_KEY_BLOCK_MASK 0x1FFFFFFF
    201#define UBIFS_S_KEY_HASH_BITS  UBIFS_S_KEY_BLOCK_BITS
    202#define UBIFS_S_KEY_HASH_MASK  UBIFS_S_KEY_BLOCK_MASK
    203
    204/*
    205 * Key types.
    206 *
    207 * UBIFS_INO_KEY: inode node key
    208 * UBIFS_DATA_KEY: data node key
    209 * UBIFS_DENT_KEY: directory entry node key
    210 * UBIFS_XENT_KEY: extended attribute entry key
    211 * UBIFS_KEY_TYPES_CNT: number of supported key types
    212 */
    213enum {
    214	UBIFS_INO_KEY,
    215	UBIFS_DATA_KEY,
    216	UBIFS_DENT_KEY,
    217	UBIFS_XENT_KEY,
    218	UBIFS_KEY_TYPES_CNT,
    219};
    220
    221/* Count of LEBs reserved for the superblock area */
    222#define UBIFS_SB_LEBS 1
    223/* Count of LEBs reserved for the master area */
    224#define UBIFS_MST_LEBS 2
    225
    226/* First LEB of the superblock area */
    227#define UBIFS_SB_LNUM 0
    228/* First LEB of the master area */
    229#define UBIFS_MST_LNUM (UBIFS_SB_LNUM + UBIFS_SB_LEBS)
    230/* First LEB of the log area */
    231#define UBIFS_LOG_LNUM (UBIFS_MST_LNUM + UBIFS_MST_LEBS)
    232
    233/*
    234 * The below constants define the absolute minimum values for various UBIFS
    235 * media areas. Many of them actually depend of flash geometry and the FS
    236 * configuration (number of journal heads, orphan LEBs, etc). This means that
    237 * the smallest volume size which can be used for UBIFS cannot be pre-defined
    238 * by these constants. The file-system that meets the below limitation will not
    239 * necessarily mount. UBIFS does run-time calculations and validates the FS
    240 * size.
    241 */
    242
    243/* Minimum number of logical eraseblocks in the log */
    244#define UBIFS_MIN_LOG_LEBS 2
    245/* Minimum number of bud logical eraseblocks (one for each head) */
    246#define UBIFS_MIN_BUD_LEBS 3
    247/* Minimum number of journal logical eraseblocks */
    248#define UBIFS_MIN_JNL_LEBS (UBIFS_MIN_LOG_LEBS + UBIFS_MIN_BUD_LEBS)
    249/* Minimum number of LPT area logical eraseblocks */
    250#define UBIFS_MIN_LPT_LEBS 2
    251/* Minimum number of orphan area logical eraseblocks */
    252#define UBIFS_MIN_ORPH_LEBS 1
    253/*
    254 * Minimum number of main area logical eraseblocks (buds, 3 for the index, 1
    255 * for GC, 1 for deletions, and at least 1 for committed data).
    256 */
    257#define UBIFS_MIN_MAIN_LEBS (UBIFS_MIN_BUD_LEBS + 6)
    258
    259/* Minimum number of logical eraseblocks */
    260#define UBIFS_MIN_LEB_CNT (UBIFS_SB_LEBS + UBIFS_MST_LEBS + \
    261			   UBIFS_MIN_LOG_LEBS + UBIFS_MIN_LPT_LEBS + \
    262			   UBIFS_MIN_ORPH_LEBS + UBIFS_MIN_MAIN_LEBS)
    263
    264/* Node sizes (N.B. these are guaranteed to be multiples of 8) */
    265#define UBIFS_CH_SZ        sizeof(struct ubifs_ch)
    266#define UBIFS_INO_NODE_SZ  sizeof(struct ubifs_ino_node)
    267#define UBIFS_DATA_NODE_SZ sizeof(struct ubifs_data_node)
    268#define UBIFS_DENT_NODE_SZ sizeof(struct ubifs_dent_node)
    269#define UBIFS_TRUN_NODE_SZ sizeof(struct ubifs_trun_node)
    270#define UBIFS_PAD_NODE_SZ  sizeof(struct ubifs_pad_node)
    271#define UBIFS_SB_NODE_SZ   sizeof(struct ubifs_sb_node)
    272#define UBIFS_MST_NODE_SZ  sizeof(struct ubifs_mst_node)
    273#define UBIFS_REF_NODE_SZ  sizeof(struct ubifs_ref_node)
    274#define UBIFS_IDX_NODE_SZ  sizeof(struct ubifs_idx_node)
    275#define UBIFS_CS_NODE_SZ   sizeof(struct ubifs_cs_node)
    276#define UBIFS_ORPH_NODE_SZ sizeof(struct ubifs_orph_node)
    277#define UBIFS_AUTH_NODE_SZ sizeof(struct ubifs_auth_node)
    278#define UBIFS_SIG_NODE_SZ  sizeof(struct ubifs_sig_node)
    279
    280/* Extended attribute entry nodes are identical to directory entry nodes */
    281#define UBIFS_XENT_NODE_SZ UBIFS_DENT_NODE_SZ
    282/* Only this does not have to be multiple of 8 bytes */
    283#define UBIFS_BRANCH_SZ    sizeof(struct ubifs_branch)
    284
    285/* Maximum node sizes (N.B. these are guaranteed to be multiples of 8) */
    286#define UBIFS_MAX_DATA_NODE_SZ  (UBIFS_DATA_NODE_SZ + UBIFS_BLOCK_SIZE)
    287#define UBIFS_MAX_INO_NODE_SZ   (UBIFS_INO_NODE_SZ + UBIFS_MAX_INO_DATA)
    288#define UBIFS_MAX_DENT_NODE_SZ  (UBIFS_DENT_NODE_SZ + UBIFS_MAX_NLEN + 1)
    289#define UBIFS_MAX_XENT_NODE_SZ  UBIFS_MAX_DENT_NODE_SZ
    290
    291/* The largest UBIFS node */
    292#define UBIFS_MAX_NODE_SZ UBIFS_MAX_INO_NODE_SZ
    293
    294/* The maxmimum size of a hash, enough for sha512 */
    295#define UBIFS_MAX_HASH_LEN 64
    296
    297/* The maxmimum size of a hmac, enough for hmac(sha512) */
    298#define UBIFS_MAX_HMAC_LEN 64
    299
    300/*
    301 * xattr name of UBIFS encryption context, we don't use a prefix
    302 * nor a long name to not waste space on the flash.
    303 */
    304#define UBIFS_XATTR_NAME_ENCRYPTION_CONTEXT "c"
    305
    306/* Type field in ubifs_sig_node */
    307#define UBIFS_SIGNATURE_TYPE_PKCS7	1
    308
    309/*
    310 * On-flash inode flags.
    311 *
    312 * UBIFS_COMPR_FL: use compression for this inode
    313 * UBIFS_SYNC_FL:  I/O on this inode has to be synchronous
    314 * UBIFS_IMMUTABLE_FL: inode is immutable
    315 * UBIFS_APPEND_FL: writes to the inode may only append data
    316 * UBIFS_DIRSYNC_FL: I/O on this directory inode has to be synchronous
    317 * UBIFS_XATTR_FL: this inode is the inode for an extended attribute value
    318 * UBIFS_CRYPT_FL: use encryption for this inode
    319 *
    320 * Note, these are on-flash flags which correspond to ioctl flags
    321 * (@FS_COMPR_FL, etc). They have the same values now, but generally, do not
    322 * have to be the same.
    323 */
    324enum {
    325	UBIFS_COMPR_FL     = 0x01,
    326	UBIFS_SYNC_FL      = 0x02,
    327	UBIFS_IMMUTABLE_FL = 0x04,
    328	UBIFS_APPEND_FL    = 0x08,
    329	UBIFS_DIRSYNC_FL   = 0x10,
    330	UBIFS_XATTR_FL     = 0x20,
    331	UBIFS_CRYPT_FL     = 0x40,
    332};
    333
    334/* Inode flag bits used by UBIFS */
    335#define UBIFS_FL_MASK 0x0000001F
    336
    337/*
    338 * UBIFS compression algorithms.
    339 *
    340 * UBIFS_COMPR_NONE: no compression
    341 * UBIFS_COMPR_LZO: LZO compression
    342 * UBIFS_COMPR_ZLIB: ZLIB compression
    343 * UBIFS_COMPR_ZSTD: ZSTD compression
    344 * UBIFS_COMPR_TYPES_CNT: count of supported compression types
    345 */
    346enum {
    347	UBIFS_COMPR_NONE,
    348	UBIFS_COMPR_LZO,
    349	UBIFS_COMPR_ZLIB,
    350	UBIFS_COMPR_ZSTD,
    351	UBIFS_COMPR_TYPES_CNT,
    352};
    353
    354/*
    355 * UBIFS node types.
    356 *
    357 * UBIFS_INO_NODE: inode node
    358 * UBIFS_DATA_NODE: data node
    359 * UBIFS_DENT_NODE: directory entry node
    360 * UBIFS_XENT_NODE: extended attribute node
    361 * UBIFS_TRUN_NODE: truncation node
    362 * UBIFS_PAD_NODE: padding node
    363 * UBIFS_SB_NODE: superblock node
    364 * UBIFS_MST_NODE: master node
    365 * UBIFS_REF_NODE: LEB reference node
    366 * UBIFS_IDX_NODE: index node
    367 * UBIFS_CS_NODE: commit start node
    368 * UBIFS_ORPH_NODE: orphan node
    369 * UBIFS_AUTH_NODE: authentication node
    370 * UBIFS_SIG_NODE: signature node
    371 * UBIFS_NODE_TYPES_CNT: count of supported node types
    372 *
    373 * Note, we index arrays by these numbers, so keep them low and contiguous.
    374 * Node type constants for inodes, direntries and so on have to be the same as
    375 * corresponding key type constants.
    376 */
    377enum {
    378	UBIFS_INO_NODE,
    379	UBIFS_DATA_NODE,
    380	UBIFS_DENT_NODE,
    381	UBIFS_XENT_NODE,
    382	UBIFS_TRUN_NODE,
    383	UBIFS_PAD_NODE,
    384	UBIFS_SB_NODE,
    385	UBIFS_MST_NODE,
    386	UBIFS_REF_NODE,
    387	UBIFS_IDX_NODE,
    388	UBIFS_CS_NODE,
    389	UBIFS_ORPH_NODE,
    390	UBIFS_AUTH_NODE,
    391	UBIFS_SIG_NODE,
    392	UBIFS_NODE_TYPES_CNT,
    393};
    394
    395/*
    396 * Master node flags.
    397 *
    398 * UBIFS_MST_DIRTY: rebooted uncleanly - master node is dirty
    399 * UBIFS_MST_NO_ORPHS: no orphan inodes present
    400 * UBIFS_MST_RCVRY: written by recovery
    401 */
    402enum {
    403	UBIFS_MST_DIRTY = 1,
    404	UBIFS_MST_NO_ORPHS = 2,
    405	UBIFS_MST_RCVRY = 4,
    406};
    407
    408/*
    409 * Node group type (used by recovery to recover whole group or none).
    410 *
    411 * UBIFS_NO_NODE_GROUP: this node is not part of a group
    412 * UBIFS_IN_NODE_GROUP: this node is a part of a group
    413 * UBIFS_LAST_OF_NODE_GROUP: this node is the last in a group
    414 */
    415enum {
    416	UBIFS_NO_NODE_GROUP = 0,
    417	UBIFS_IN_NODE_GROUP,
    418	UBIFS_LAST_OF_NODE_GROUP,
    419};
    420
    421/*
    422 * Superblock flags.
    423 *
    424 * UBIFS_FLG_BIGLPT: if "big" LPT model is used if set
    425 * UBIFS_FLG_SPACE_FIXUP: first-mount "fixup" of free space within LEBs needed
    426 * UBIFS_FLG_DOUBLE_HASH: store a 32bit cookie in directory entry nodes to
    427 *			  support 64bit cookies for lookups by hash
    428 * UBIFS_FLG_ENCRYPTION: this filesystem contains encrypted files
    429 * UBIFS_FLG_AUTHENTICATION: this filesystem contains hashes for authentication
    430 */
    431enum {
    432	UBIFS_FLG_BIGLPT = 0x02,
    433	UBIFS_FLG_SPACE_FIXUP = 0x04,
    434	UBIFS_FLG_DOUBLE_HASH = 0x08,
    435	UBIFS_FLG_ENCRYPTION = 0x10,
    436	UBIFS_FLG_AUTHENTICATION = 0x20,
    437};
    438
    439#define UBIFS_FLG_MASK (UBIFS_FLG_BIGLPT | UBIFS_FLG_SPACE_FIXUP | \
    440		UBIFS_FLG_DOUBLE_HASH | UBIFS_FLG_ENCRYPTION | \
    441		UBIFS_FLG_AUTHENTICATION)
    442
    443/**
    444 * struct ubifs_ch - common header node.
    445 * @magic: UBIFS node magic number (%UBIFS_NODE_MAGIC)
    446 * @crc: CRC-32 checksum of the node header
    447 * @sqnum: sequence number
    448 * @len: full node length
    449 * @node_type: node type
    450 * @group_type: node group type
    451 * @padding: reserved for future, zeroes
    452 *
    453 * Every UBIFS node starts with this common part. If the node has a key, the
    454 * key always goes next.
    455 */
    456struct ubifs_ch {
    457	__le32 magic;
    458	__le32 crc;
    459	__le64 sqnum;
    460	__le32 len;
    461	__u8 node_type;
    462	__u8 group_type;
    463	__u8 padding[2];
    464} __packed;
    465
    466/**
    467 * union ubifs_dev_desc - device node descriptor.
    468 * @new: new type device descriptor
    469 * @huge: huge type device descriptor
    470 *
    471 * This data structure describes major/minor numbers of a device node. In an
    472 * inode is a device node then its data contains an object of this type. UBIFS
    473 * uses standard Linux "new" and "huge" device node encodings.
    474 */
    475union ubifs_dev_desc {
    476	__le32 new;
    477	__le64 huge;
    478} __packed;
    479
    480/**
    481 * struct ubifs_ino_node - inode node.
    482 * @ch: common header
    483 * @key: node key
    484 * @creat_sqnum: sequence number at time of creation
    485 * @size: inode size in bytes (amount of uncompressed data)
    486 * @atime_sec: access time seconds
    487 * @ctime_sec: creation time seconds
    488 * @mtime_sec: modification time seconds
    489 * @atime_nsec: access time nanoseconds
    490 * @ctime_nsec: creation time nanoseconds
    491 * @mtime_nsec: modification time nanoseconds
    492 * @nlink: number of hard links
    493 * @uid: owner ID
    494 * @gid: group ID
    495 * @mode: access flags
    496 * @flags: per-inode flags (%UBIFS_COMPR_FL, %UBIFS_SYNC_FL, etc)
    497 * @data_len: inode data length
    498 * @xattr_cnt: count of extended attributes this inode has
    499 * @xattr_size: summarized size of all extended attributes in bytes
    500 * @padding1: reserved for future, zeroes
    501 * @xattr_names: sum of lengths of all extended attribute names belonging to
    502 *               this inode
    503 * @compr_type: compression type used for this inode
    504 * @padding2: reserved for future, zeroes
    505 * @data: data attached to the inode
    506 *
    507 * Note, even though inode compression type is defined by @compr_type, some
    508 * nodes of this inode may be compressed with different compressor - this
    509 * happens if compression type is changed while the inode already has data
    510 * nodes. But @compr_type will be use for further writes to the inode.
    511 *
    512 * Note, do not forget to amend 'zero_ino_node_unused()' function when changing
    513 * the padding fields.
    514 */
    515struct ubifs_ino_node {
    516	struct ubifs_ch ch;
    517	__u8 key[UBIFS_MAX_KEY_LEN];
    518	__le64 creat_sqnum;
    519	__le64 size;
    520	__le64 atime_sec;
    521	__le64 ctime_sec;
    522	__le64 mtime_sec;
    523	__le32 atime_nsec;
    524	__le32 ctime_nsec;
    525	__le32 mtime_nsec;
    526	__le32 nlink;
    527	__le32 uid;
    528	__le32 gid;
    529	__le32 mode;
    530	__le32 flags;
    531	__le32 data_len;
    532	__le32 xattr_cnt;
    533	__le32 xattr_size;
    534	__u8 padding1[4]; /* Watch 'zero_ino_node_unused()' if changing! */
    535	__le32 xattr_names;
    536	__le16 compr_type;
    537	__u8 padding2[26]; /* Watch 'zero_ino_node_unused()' if changing! */
    538	__u8 data[];
    539} __packed;
    540
    541/**
    542 * struct ubifs_dent_node - directory entry node.
    543 * @ch: common header
    544 * @key: node key
    545 * @inum: target inode number
    546 * @padding1: reserved for future, zeroes
    547 * @type: type of the target inode (%UBIFS_ITYPE_REG, %UBIFS_ITYPE_DIR, etc)
    548 * @nlen: name length
    549 * @cookie: A 32bits random number, used to construct a 64bits
    550 *          identifier.
    551 * @name: zero-terminated name
    552 *
    553 * Note, do not forget to amend 'zero_dent_node_unused()' function when
    554 * changing the padding fields.
    555 */
    556struct ubifs_dent_node {
    557	struct ubifs_ch ch;
    558	__u8 key[UBIFS_MAX_KEY_LEN];
    559	__le64 inum;
    560	__u8 padding1;
    561	__u8 type;
    562	__le16 nlen;
    563	__le32 cookie;
    564	__u8 name[];
    565} __packed;
    566
    567/**
    568 * struct ubifs_data_node - data node.
    569 * @ch: common header
    570 * @key: node key
    571 * @size: uncompressed data size in bytes
    572 * @compr_type: compression type (%UBIFS_COMPR_NONE, %UBIFS_COMPR_LZO, etc)
    573 * @compr_size: compressed data size in bytes, only valid when data is encrypted
    574 * @data: data
    575 *
    576 */
    577struct ubifs_data_node {
    578	struct ubifs_ch ch;
    579	__u8 key[UBIFS_MAX_KEY_LEN];
    580	__le32 size;
    581	__le16 compr_type;
    582	__le16 compr_size;
    583	__u8 data[];
    584} __packed;
    585
    586/**
    587 * struct ubifs_trun_node - truncation node.
    588 * @ch: common header
    589 * @inum: truncated inode number
    590 * @padding: reserved for future, zeroes
    591 * @old_size: size before truncation
    592 * @new_size: size after truncation
    593 *
    594 * This node exists only in the journal and never goes to the main area. Note,
    595 * do not forget to amend 'zero_trun_node_unused()' function when changing the
    596 * padding fields.
    597 */
    598struct ubifs_trun_node {
    599	struct ubifs_ch ch;
    600	__le32 inum;
    601	__u8 padding[12]; /* Watch 'zero_trun_node_unused()' if changing! */
    602	__le64 old_size;
    603	__le64 new_size;
    604} __packed;
    605
    606/**
    607 * struct ubifs_pad_node - padding node.
    608 * @ch: common header
    609 * @pad_len: how many bytes after this node are unused (because padded)
    610 * @padding: reserved for future, zeroes
    611 */
    612struct ubifs_pad_node {
    613	struct ubifs_ch ch;
    614	__le32 pad_len;
    615} __packed;
    616
    617/**
    618 * struct ubifs_sb_node - superblock node.
    619 * @ch: common header
    620 * @padding: reserved for future, zeroes
    621 * @key_hash: type of hash function used in keys
    622 * @key_fmt: format of the key
    623 * @flags: file-system flags (%UBIFS_FLG_BIGLPT, etc)
    624 * @min_io_size: minimal input/output unit size
    625 * @leb_size: logical eraseblock size in bytes
    626 * @leb_cnt: count of LEBs used by file-system
    627 * @max_leb_cnt: maximum count of LEBs used by file-system
    628 * @max_bud_bytes: maximum amount of data stored in buds
    629 * @log_lebs: log size in logical eraseblocks
    630 * @lpt_lebs: number of LEBs used for lprops table
    631 * @orph_lebs: number of LEBs used for recording orphans
    632 * @jhead_cnt: count of journal heads
    633 * @fanout: tree fanout (max. number of links per indexing node)
    634 * @lsave_cnt: number of LEB numbers in LPT's save table
    635 * @fmt_version: UBIFS on-flash format version
    636 * @default_compr: default compression algorithm (%UBIFS_COMPR_LZO, etc)
    637 * @padding1: reserved for future, zeroes
    638 * @rp_uid: reserve pool UID
    639 * @rp_gid: reserve pool GID
    640 * @rp_size: size of the reserved pool in bytes
    641 * @padding2: reserved for future, zeroes
    642 * @time_gran: time granularity in nanoseconds
    643 * @uuid: UUID generated when the file system image was created
    644 * @ro_compat_version: UBIFS R/O compatibility version
    645 * @hmac: HMAC to authenticate the superblock node
    646 * @hmac_wkm: HMAC of a well known message (the string "UBIFS") as a convenience
    647 *            to the user to check if the correct key is passed.
    648 * @hash_algo: The hash algo used for this filesystem (one of enum hash_algo)
    649 * @hash_mst: hash of the master node, only valid for signed images in which the
    650 *            master node does not contain a hmac
    651 */
    652struct ubifs_sb_node {
    653	struct ubifs_ch ch;
    654	__u8 padding[2];
    655	__u8 key_hash;
    656	__u8 key_fmt;
    657	__le32 flags;
    658	__le32 min_io_size;
    659	__le32 leb_size;
    660	__le32 leb_cnt;
    661	__le32 max_leb_cnt;
    662	__le64 max_bud_bytes;
    663	__le32 log_lebs;
    664	__le32 lpt_lebs;
    665	__le32 orph_lebs;
    666	__le32 jhead_cnt;
    667	__le32 fanout;
    668	__le32 lsave_cnt;
    669	__le32 fmt_version;
    670	__le16 default_compr;
    671	__u8 padding1[2];
    672	__le32 rp_uid;
    673	__le32 rp_gid;
    674	__le64 rp_size;
    675	__le32 time_gran;
    676	__u8 uuid[16];
    677	__le32 ro_compat_version;
    678	__u8 hmac[UBIFS_MAX_HMAC_LEN];
    679	__u8 hmac_wkm[UBIFS_MAX_HMAC_LEN];
    680	__le16 hash_algo;
    681	__u8 hash_mst[UBIFS_MAX_HASH_LEN];
    682	__u8 padding2[3774];
    683} __packed;
    684
    685/**
    686 * struct ubifs_mst_node - master node.
    687 * @ch: common header
    688 * @highest_inum: highest inode number in the committed index
    689 * @cmt_no: commit number
    690 * @flags: various flags (%UBIFS_MST_DIRTY, etc)
    691 * @log_lnum: start of the log
    692 * @root_lnum: LEB number of the root indexing node
    693 * @root_offs: offset within @root_lnum
    694 * @root_len: root indexing node length
    695 * @gc_lnum: LEB reserved for garbage collection (%-1 value means the LEB was
    696 * not reserved and should be reserved on mount)
    697 * @ihead_lnum: LEB number of index head
    698 * @ihead_offs: offset of index head
    699 * @index_size: size of index on flash
    700 * @total_free: total free space in bytes
    701 * @total_dirty: total dirty space in bytes
    702 * @total_used: total used space in bytes (includes only data LEBs)
    703 * @total_dead: total dead space in bytes (includes only data LEBs)
    704 * @total_dark: total dark space in bytes (includes only data LEBs)
    705 * @lpt_lnum: LEB number of LPT root nnode
    706 * @lpt_offs: offset of LPT root nnode
    707 * @nhead_lnum: LEB number of LPT head
    708 * @nhead_offs: offset of LPT head
    709 * @ltab_lnum: LEB number of LPT's own lprops table
    710 * @ltab_offs: offset of LPT's own lprops table
    711 * @lsave_lnum: LEB number of LPT's save table (big model only)
    712 * @lsave_offs: offset of LPT's save table (big model only)
    713 * @lscan_lnum: LEB number of last LPT scan
    714 * @empty_lebs: number of empty logical eraseblocks
    715 * @idx_lebs: number of indexing logical eraseblocks
    716 * @leb_cnt: count of LEBs used by file-system
    717 * @hash_root_idx: the hash of the root index node
    718 * @hash_lpt: the hash of the LPT
    719 * @hmac: HMAC to authenticate the master node
    720 * @padding: reserved for future, zeroes
    721 */
    722struct ubifs_mst_node {
    723	struct ubifs_ch ch;
    724	__le64 highest_inum;
    725	__le64 cmt_no;
    726	__le32 flags;
    727	__le32 log_lnum;
    728	__le32 root_lnum;
    729	__le32 root_offs;
    730	__le32 root_len;
    731	__le32 gc_lnum;
    732	__le32 ihead_lnum;
    733	__le32 ihead_offs;
    734	__le64 index_size;
    735	__le64 total_free;
    736	__le64 total_dirty;
    737	__le64 total_used;
    738	__le64 total_dead;
    739	__le64 total_dark;
    740	__le32 lpt_lnum;
    741	__le32 lpt_offs;
    742	__le32 nhead_lnum;
    743	__le32 nhead_offs;
    744	__le32 ltab_lnum;
    745	__le32 ltab_offs;
    746	__le32 lsave_lnum;
    747	__le32 lsave_offs;
    748	__le32 lscan_lnum;
    749	__le32 empty_lebs;
    750	__le32 idx_lebs;
    751	__le32 leb_cnt;
    752	__u8 hash_root_idx[UBIFS_MAX_HASH_LEN];
    753	__u8 hash_lpt[UBIFS_MAX_HASH_LEN];
    754	__u8 hmac[UBIFS_MAX_HMAC_LEN];
    755	__u8 padding[152];
    756} __packed;
    757
    758/**
    759 * struct ubifs_ref_node - logical eraseblock reference node.
    760 * @ch: common header
    761 * @lnum: the referred logical eraseblock number
    762 * @offs: start offset in the referred LEB
    763 * @jhead: journal head number
    764 * @padding: reserved for future, zeroes
    765 */
    766struct ubifs_ref_node {
    767	struct ubifs_ch ch;
    768	__le32 lnum;
    769	__le32 offs;
    770	__le32 jhead;
    771	__u8 padding[28];
    772} __packed;
    773
    774/**
    775 * struct ubifs_auth_node - node for authenticating other nodes
    776 * @ch: common header
    777 * @hmac: The HMAC
    778 */
    779struct ubifs_auth_node {
    780	struct ubifs_ch ch;
    781	__u8 hmac[];
    782} __packed;
    783
    784/**
    785 * struct ubifs_sig_node - node for signing other nodes
    786 * @ch: common header
    787 * @type: type of the signature, currently only UBIFS_SIGNATURE_TYPE_PKCS7
    788 * supported
    789 * @len: The length of the signature data
    790 * @padding: reserved for future, zeroes
    791 * @sig: The signature data
    792 */
    793struct ubifs_sig_node {
    794	struct ubifs_ch ch;
    795	__le32 type;
    796	__le32 len;
    797	__u8 padding[32];
    798	__u8 sig[];
    799} __packed;
    800
    801/**
    802 * struct ubifs_branch - key/reference/length branch
    803 * @lnum: LEB number of the target node
    804 * @offs: offset within @lnum
    805 * @len: target node length
    806 * @key: key
    807 *
    808 * In an authenticated UBIFS we have the hash of the referenced node after @key.
    809 * This can't be added to the struct type definition because @key is a
    810 * dynamically sized element already.
    811 */
    812struct ubifs_branch {
    813	__le32 lnum;
    814	__le32 offs;
    815	__le32 len;
    816	__u8 key[];
    817} __packed;
    818
    819/**
    820 * struct ubifs_idx_node - indexing node.
    821 * @ch: common header
    822 * @child_cnt: number of child index nodes
    823 * @level: tree level
    824 * @branches: LEB number / offset / length / key branches
    825 */
    826struct ubifs_idx_node {
    827	struct ubifs_ch ch;
    828	__le16 child_cnt;
    829	__le16 level;
    830	__u8 branches[];
    831} __packed;
    832
    833/**
    834 * struct ubifs_cs_node - commit start node.
    835 * @ch: common header
    836 * @cmt_no: commit number
    837 */
    838struct ubifs_cs_node {
    839	struct ubifs_ch ch;
    840	__le64 cmt_no;
    841} __packed;
    842
    843/**
    844 * struct ubifs_orph_node - orphan node.
    845 * @ch: common header
    846 * @cmt_no: commit number (also top bit is set on the last node of the commit)
    847 * @inos: inode numbers of orphans
    848 */
    849struct ubifs_orph_node {
    850	struct ubifs_ch ch;
    851	__le64 cmt_no;
    852	__le64 inos[];
    853} __packed;
    854
    855#endif /* __UBIFS_MEDIA_H__ */