custom_sec_handlers.c (5673B)
1// SPDX-License-Identifier: GPL-2.0 2/* Copyright (c) 2022 Facebook */ 3 4#include <test_progs.h> 5#include "test_custom_sec_handlers.skel.h" 6 7#define COOKIE_ABC1 1 8#define COOKIE_ABC2 2 9#define COOKIE_CUSTOM 3 10#define COOKIE_FALLBACK 4 11#define COOKIE_KPROBE 5 12 13static int custom_setup_prog(struct bpf_program *prog, long cookie) 14{ 15 if (cookie == COOKIE_ABC1) 16 bpf_program__set_autoload(prog, false); 17 18 return 0; 19} 20 21static int custom_prepare_load_prog(struct bpf_program *prog, 22 struct bpf_prog_load_opts *opts, long cookie) 23{ 24 if (cookie == COOKIE_FALLBACK) 25 opts->prog_flags |= BPF_F_SLEEPABLE; 26 else if (cookie == COOKIE_ABC1) 27 ASSERT_FALSE(true, "unexpected preload for abc"); 28 29 return 0; 30} 31 32static int custom_attach_prog(const struct bpf_program *prog, long cookie, 33 struct bpf_link **link) 34{ 35 switch (cookie) { 36 case COOKIE_ABC2: 37 *link = bpf_program__attach_raw_tracepoint(prog, "sys_enter"); 38 return libbpf_get_error(*link); 39 case COOKIE_CUSTOM: 40 *link = bpf_program__attach_tracepoint(prog, "syscalls", "sys_enter_nanosleep"); 41 return libbpf_get_error(*link); 42 case COOKIE_KPROBE: 43 case COOKIE_FALLBACK: 44 /* no auto-attach for SEC("xyz") and SEC("kprobe") */ 45 *link = NULL; 46 return 0; 47 default: 48 ASSERT_FALSE(true, "unexpected cookie"); 49 return -EINVAL; 50 } 51} 52 53static int abc1_id; 54static int abc2_id; 55static int custom_id; 56static int fallback_id; 57static int kprobe_id; 58 59__attribute__((constructor)) 60static void register_sec_handlers(void) 61{ 62 LIBBPF_OPTS(libbpf_prog_handler_opts, abc1_opts, 63 .cookie = COOKIE_ABC1, 64 .prog_setup_fn = custom_setup_prog, 65 .prog_prepare_load_fn = custom_prepare_load_prog, 66 .prog_attach_fn = NULL, 67 ); 68 LIBBPF_OPTS(libbpf_prog_handler_opts, abc2_opts, 69 .cookie = COOKIE_ABC2, 70 .prog_setup_fn = custom_setup_prog, 71 .prog_prepare_load_fn = custom_prepare_load_prog, 72 .prog_attach_fn = custom_attach_prog, 73 ); 74 LIBBPF_OPTS(libbpf_prog_handler_opts, custom_opts, 75 .cookie = COOKIE_CUSTOM, 76 .prog_setup_fn = NULL, 77 .prog_prepare_load_fn = NULL, 78 .prog_attach_fn = custom_attach_prog, 79 ); 80 81 abc1_id = libbpf_register_prog_handler("abc", BPF_PROG_TYPE_RAW_TRACEPOINT, 0, &abc1_opts); 82 abc2_id = libbpf_register_prog_handler("abc/", BPF_PROG_TYPE_RAW_TRACEPOINT, 0, &abc2_opts); 83 custom_id = libbpf_register_prog_handler("custom+", BPF_PROG_TYPE_TRACEPOINT, 0, &custom_opts); 84} 85 86__attribute__((destructor)) 87static void unregister_sec_handlers(void) 88{ 89 libbpf_unregister_prog_handler(abc1_id); 90 libbpf_unregister_prog_handler(abc2_id); 91 libbpf_unregister_prog_handler(custom_id); 92} 93 94void test_custom_sec_handlers(void) 95{ 96 LIBBPF_OPTS(libbpf_prog_handler_opts, opts, 97 .prog_setup_fn = custom_setup_prog, 98 .prog_prepare_load_fn = custom_prepare_load_prog, 99 .prog_attach_fn = custom_attach_prog, 100 ); 101 struct test_custom_sec_handlers* skel; 102 int err; 103 104 ASSERT_GT(abc1_id, 0, "abc1_id"); 105 ASSERT_GT(abc2_id, 0, "abc2_id"); 106 ASSERT_GT(custom_id, 0, "custom_id"); 107 108 /* override libbpf's handle of SEC("kprobe/...") but also allow pure 109 * SEC("kprobe") due to "kprobe+" specifier. Register it as 110 * TRACEPOINT, just for fun. 111 */ 112 opts.cookie = COOKIE_KPROBE; 113 kprobe_id = libbpf_register_prog_handler("kprobe+", BPF_PROG_TYPE_TRACEPOINT, 0, &opts); 114 /* fallback treats everything as BPF_PROG_TYPE_SYSCALL program to test 115 * setting custom BPF_F_SLEEPABLE bit in preload handler 116 */ 117 opts.cookie = COOKIE_FALLBACK; 118 fallback_id = libbpf_register_prog_handler(NULL, BPF_PROG_TYPE_SYSCALL, 0, &opts); 119 120 if (!ASSERT_GT(fallback_id, 0, "fallback_id") /* || !ASSERT_GT(kprobe_id, 0, "kprobe_id")*/) { 121 if (fallback_id > 0) 122 libbpf_unregister_prog_handler(fallback_id); 123 if (kprobe_id > 0) 124 libbpf_unregister_prog_handler(kprobe_id); 125 return; 126 } 127 128 /* open skeleton and validate assumptions */ 129 skel = test_custom_sec_handlers__open(); 130 if (!ASSERT_OK_PTR(skel, "skel_open")) 131 goto cleanup; 132 133 ASSERT_EQ(bpf_program__type(skel->progs.abc1), BPF_PROG_TYPE_RAW_TRACEPOINT, "abc1_type"); 134 ASSERT_FALSE(bpf_program__autoload(skel->progs.abc1), "abc1_autoload"); 135 136 ASSERT_EQ(bpf_program__type(skel->progs.abc2), BPF_PROG_TYPE_RAW_TRACEPOINT, "abc2_type"); 137 ASSERT_EQ(bpf_program__type(skel->progs.custom1), BPF_PROG_TYPE_TRACEPOINT, "custom1_type"); 138 ASSERT_EQ(bpf_program__type(skel->progs.custom2), BPF_PROG_TYPE_TRACEPOINT, "custom2_type"); 139 ASSERT_EQ(bpf_program__type(skel->progs.kprobe1), BPF_PROG_TYPE_TRACEPOINT, "kprobe1_type"); 140 ASSERT_EQ(bpf_program__type(skel->progs.xyz), BPF_PROG_TYPE_SYSCALL, "xyz_type"); 141 142 skel->rodata->my_pid = getpid(); 143 144 /* now attempt to load everything */ 145 err = test_custom_sec_handlers__load(skel); 146 if (!ASSERT_OK(err, "skel_load")) 147 goto cleanup; 148 149 /* now try to auto-attach everything */ 150 err = test_custom_sec_handlers__attach(skel); 151 if (!ASSERT_OK(err, "skel_attach")) 152 goto cleanup; 153 154 skel->links.xyz = bpf_program__attach(skel->progs.kprobe1); 155 ASSERT_EQ(errno, EOPNOTSUPP, "xyz_attach_err"); 156 ASSERT_ERR_PTR(skel->links.xyz, "xyz_attach"); 157 158 /* trigger programs */ 159 usleep(1); 160 161 /* SEC("abc") is set to not auto-loaded */ 162 ASSERT_FALSE(skel->bss->abc1_called, "abc1_called"); 163 ASSERT_TRUE(skel->bss->abc2_called, "abc2_called"); 164 ASSERT_TRUE(skel->bss->custom1_called, "custom1_called"); 165 ASSERT_TRUE(skel->bss->custom2_called, "custom2_called"); 166 /* SEC("kprobe") shouldn't be auto-attached */ 167 ASSERT_FALSE(skel->bss->kprobe1_called, "kprobe1_called"); 168 /* SEC("xyz") shouldn't be auto-attached */ 169 ASSERT_FALSE(skel->bss->xyz_called, "xyz_called"); 170 171cleanup: 172 test_custom_sec_handlers__destroy(skel); 173 174 ASSERT_OK(libbpf_unregister_prog_handler(fallback_id), "unregister_fallback"); 175 ASSERT_OK(libbpf_unregister_prog_handler(kprobe_id), "unregister_kprobe"); 176}