1 /* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */ 2 3 /* 4 * Common eBPF ELF object loading operations. 5 * 6 * Copyright (C) 2013-2015 Alexei Starovoitov <ast@kernel.org> 7 * Copyright (C) 2015 Wang Nan <wangnan0@huawei.com> 8 * Copyright (C) 2015 Huawei Inc. 9 */ 10 #ifndef __LIBBPF_LIBBPF_H 11 #define __LIBBPF_LIBBPF_H 12 13 #include <stdio.h> 14 #include <stdint.h> 15 #include <stdbool.h> 16 #include <sys/types.h> // for size_t 17 #include <linux/bpf.h> 18 19 #ifdef __cplusplus 20 extern "C" { 21 #endif 22 23 #ifndef LIBBPF_API 24 #define LIBBPF_API __attribute__((visibility("default"))) 25 #endif 26 27 enum libbpf_errno { 28 __LIBBPF_ERRNO__START = 4000, 29 30 /* Something wrong in libelf */ 31 LIBBPF_ERRNO__LIBELF = __LIBBPF_ERRNO__START, 32 LIBBPF_ERRNO__FORMAT, /* BPF object format invalid */ 33 LIBBPF_ERRNO__KVERSION, /* Incorrect or no 'version' section */ 34 LIBBPF_ERRNO__ENDIAN, /* Endian mismatch */ 35 LIBBPF_ERRNO__INTERNAL, /* Internal error in libbpf */ 36 LIBBPF_ERRNO__RELOC, /* Relocation failed */ 37 LIBBPF_ERRNO__LOAD, /* Load program failure for unknown reason */ 38 LIBBPF_ERRNO__VERIFY, /* Kernel verifier blocks program loading */ 39 LIBBPF_ERRNO__PROG2BIG, /* Program too big */ 40 LIBBPF_ERRNO__KVER, /* Incorrect kernel version */ 41 LIBBPF_ERRNO__PROGTYPE, /* Kernel doesn't support this program type */ 42 LIBBPF_ERRNO__WRNGPID, /* Wrong pid in netlink message */ 43 LIBBPF_ERRNO__INVSEQ, /* Invalid netlink sequence */ 44 LIBBPF_ERRNO__NLPARSE, /* netlink parsing error */ 45 __LIBBPF_ERRNO__END, 46 }; 47 48 LIBBPF_API int libbpf_strerror(int err, char *buf, size_t size); 49 50 enum libbpf_print_level { 51 LIBBPF_WARN, 52 LIBBPF_INFO, 53 LIBBPF_DEBUG, 54 }; 55 56 typedef int (*libbpf_print_fn_t)(enum libbpf_print_level level, 57 const char *, va_list ap); 58 59 LIBBPF_API void libbpf_set_print(libbpf_print_fn_t fn); 60 61 /* Hide internal to user */ 62 struct bpf_object; 63 64 struct bpf_object_open_attr { 65 const char *file; 66 enum bpf_prog_type prog_type; 67 }; 68 69 LIBBPF_API struct bpf_object *bpf_object__open(const char *path); 70 LIBBPF_API struct bpf_object * 71 bpf_object__open_xattr(struct bpf_object_open_attr *attr); 72 struct bpf_object *__bpf_object__open_xattr(struct bpf_object_open_attr *attr, 73 int flags); 74 LIBBPF_API struct bpf_object *bpf_object__open_buffer(void *obj_buf, 75 size_t obj_buf_sz, 76 const char *name); 77 LIBBPF_API int bpf_object__pin_maps(struct bpf_object *obj, const char *path); 78 LIBBPF_API int bpf_object__unpin_maps(struct bpf_object *obj, 79 const char *path); 80 LIBBPF_API int bpf_object__pin_programs(struct bpf_object *obj, 81 const char *path); 82 LIBBPF_API int bpf_object__unpin_programs(struct bpf_object *obj, 83 const char *path); 84 LIBBPF_API int bpf_object__pin(struct bpf_object *object, const char *path); 85 LIBBPF_API void bpf_object__close(struct bpf_object *object); 86 87 /* Load/unload object into/from kernel */ 88 LIBBPF_API int bpf_object__load(struct bpf_object *obj); 89 LIBBPF_API int bpf_object__unload(struct bpf_object *obj); 90 LIBBPF_API const char *bpf_object__name(struct bpf_object *obj); 91 LIBBPF_API unsigned int bpf_object__kversion(struct bpf_object *obj); 92 93 struct btf; 94 LIBBPF_API struct btf *bpf_object__btf(struct bpf_object *obj); 95 LIBBPF_API int bpf_object__btf_fd(const struct bpf_object *obj); 96 97 LIBBPF_API struct bpf_program * 98 bpf_object__find_program_by_title(struct bpf_object *obj, const char *title); 99 100 LIBBPF_API struct bpf_object *bpf_object__next(struct bpf_object *prev); 101 #define bpf_object__for_each_safe(pos, tmp) \ 102 for ((pos) = bpf_object__next(NULL), \ 103 (tmp) = bpf_object__next(pos); \ 104 (pos) != NULL; \ 105 (pos) = (tmp), (tmp) = bpf_object__next(tmp)) 106 107 typedef void (*bpf_object_clear_priv_t)(struct bpf_object *, void *); 108 LIBBPF_API int bpf_object__set_priv(struct bpf_object *obj, void *priv, 109 bpf_object_clear_priv_t clear_priv); 110 LIBBPF_API void *bpf_object__priv(struct bpf_object *prog); 111 112 LIBBPF_API int 113 libbpf_prog_type_by_name(const char *name, enum bpf_prog_type *prog_type, 114 enum bpf_attach_type *expected_attach_type); 115 LIBBPF_API int libbpf_attach_type_by_name(const char *name, 116 enum bpf_attach_type *attach_type); 117 118 /* Accessors of bpf_program */ 119 struct bpf_program; 120 LIBBPF_API struct bpf_program *bpf_program__next(struct bpf_program *prog, 121 struct bpf_object *obj); 122 123 #define bpf_object__for_each_program(pos, obj) \ 124 for ((pos) = bpf_program__next(NULL, (obj)); \ 125 (pos) != NULL; \ 126 (pos) = bpf_program__next((pos), (obj))) 127 128 LIBBPF_API struct bpf_program *bpf_program__prev(struct bpf_program *prog, 129 struct bpf_object *obj); 130 131 typedef void (*bpf_program_clear_priv_t)(struct bpf_program *, 132 void *); 133 134 LIBBPF_API int bpf_program__set_priv(struct bpf_program *prog, void *priv, 135 bpf_program_clear_priv_t clear_priv); 136 137 LIBBPF_API void *bpf_program__priv(struct bpf_program *prog); 138 LIBBPF_API void bpf_program__set_ifindex(struct bpf_program *prog, 139 __u32 ifindex); 140 141 LIBBPF_API const char *bpf_program__title(struct bpf_program *prog, 142 bool needs_copy); 143 144 LIBBPF_API int bpf_program__load(struct bpf_program *prog, char *license, 145 __u32 kern_version); 146 LIBBPF_API int bpf_program__fd(struct bpf_program *prog); 147 LIBBPF_API int bpf_program__pin_instance(struct bpf_program *prog, 148 const char *path, 149 int instance); 150 LIBBPF_API int bpf_program__unpin_instance(struct bpf_program *prog, 151 const char *path, 152 int instance); 153 LIBBPF_API int bpf_program__pin(struct bpf_program *prog, const char *path); 154 LIBBPF_API int bpf_program__unpin(struct bpf_program *prog, const char *path); 155 LIBBPF_API void bpf_program__unload(struct bpf_program *prog); 156 157 struct bpf_insn; 158 159 /* 160 * Libbpf allows callers to adjust BPF programs before being loaded 161 * into kernel. One program in an object file can be transformed into 162 * multiple variants to be attached to different hooks. 163 * 164 * bpf_program_prep_t, bpf_program__set_prep and bpf_program__nth_fd 165 * form an API for this purpose. 166 * 167 * - bpf_program_prep_t: 168 * Defines a 'preprocessor', which is a caller defined function 169 * passed to libbpf through bpf_program__set_prep(), and will be 170 * called before program is loaded. The processor should adjust 171 * the program one time for each instance according to the instance id 172 * passed to it. 173 * 174 * - bpf_program__set_prep: 175 * Attaches a preprocessor to a BPF program. The number of instances 176 * that should be created is also passed through this function. 177 * 178 * - bpf_program__nth_fd: 179 * After the program is loaded, get resulting FD of a given instance 180 * of the BPF program. 181 * 182 * If bpf_program__set_prep() is not used, the program would be loaded 183 * without adjustment during bpf_object__load(). The program has only 184 * one instance. In this case bpf_program__fd(prog) is equal to 185 * bpf_program__nth_fd(prog, 0). 186 */ 187 188 struct bpf_prog_prep_result { 189 /* 190 * If not NULL, load new instruction array. 191 * If set to NULL, don't load this instance. 192 */ 193 struct bpf_insn *new_insn_ptr; 194 int new_insn_cnt; 195 196 /* If not NULL, result FD is written to it. */ 197 int *pfd; 198 }; 199 200 /* 201 * Parameters of bpf_program_prep_t: 202 * - prog: The bpf_program being loaded. 203 * - n: Index of instance being generated. 204 * - insns: BPF instructions array. 205 * - insns_cnt:Number of instructions in insns. 206 * - res: Output parameter, result of transformation. 207 * 208 * Return value: 209 * - Zero: pre-processing success. 210 * - Non-zero: pre-processing error, stop loading. 211 */ 212 typedef int (*bpf_program_prep_t)(struct bpf_program *prog, int n, 213 struct bpf_insn *insns, int insns_cnt, 214 struct bpf_prog_prep_result *res); 215 216 LIBBPF_API int bpf_program__set_prep(struct bpf_program *prog, int nr_instance, 217 bpf_program_prep_t prep); 218 219 LIBBPF_API int bpf_program__nth_fd(struct bpf_program *prog, int n); 220 221 /* 222 * Adjust type of BPF program. Default is kprobe. 223 */ 224 LIBBPF_API int bpf_program__set_socket_filter(struct bpf_program *prog); 225 LIBBPF_API int bpf_program__set_tracepoint(struct bpf_program *prog); 226 LIBBPF_API int bpf_program__set_raw_tracepoint(struct bpf_program *prog); 227 LIBBPF_API int bpf_program__set_kprobe(struct bpf_program *prog); 228 LIBBPF_API int bpf_program__set_sched_cls(struct bpf_program *prog); 229 LIBBPF_API int bpf_program__set_sched_act(struct bpf_program *prog); 230 LIBBPF_API int bpf_program__set_xdp(struct bpf_program *prog); 231 LIBBPF_API int bpf_program__set_perf_event(struct bpf_program *prog); 232 LIBBPF_API void bpf_program__set_type(struct bpf_program *prog, 233 enum bpf_prog_type type); 234 LIBBPF_API void 235 bpf_program__set_expected_attach_type(struct bpf_program *prog, 236 enum bpf_attach_type type); 237 238 LIBBPF_API bool bpf_program__is_socket_filter(struct bpf_program *prog); 239 LIBBPF_API bool bpf_program__is_tracepoint(struct bpf_program *prog); 240 LIBBPF_API bool bpf_program__is_raw_tracepoint(struct bpf_program *prog); 241 LIBBPF_API bool bpf_program__is_kprobe(struct bpf_program *prog); 242 LIBBPF_API bool bpf_program__is_sched_cls(struct bpf_program *prog); 243 LIBBPF_API bool bpf_program__is_sched_act(struct bpf_program *prog); 244 LIBBPF_API bool bpf_program__is_xdp(struct bpf_program *prog); 245 LIBBPF_API bool bpf_program__is_perf_event(struct bpf_program *prog); 246 247 /* 248 * No need for __attribute__((packed)), all members of 'bpf_map_def' 249 * are all aligned. In addition, using __attribute__((packed)) 250 * would trigger a -Wpacked warning message, and lead to an error 251 * if -Werror is set. 252 */ 253 struct bpf_map_def { 254 unsigned int type; 255 unsigned int key_size; 256 unsigned int value_size; 257 unsigned int max_entries; 258 unsigned int map_flags; 259 }; 260 261 /* 262 * The 'struct bpf_map' in include/linux/bpf.h is internal to the kernel, 263 * so no need to worry about a name clash. 264 */ 265 struct bpf_map; 266 LIBBPF_API struct bpf_map * 267 bpf_object__find_map_by_name(struct bpf_object *obj, const char *name); 268 269 LIBBPF_API int 270 bpf_object__find_map_fd_by_name(struct bpf_object *obj, const char *name); 271 272 /* 273 * Get bpf_map through the offset of corresponding struct bpf_map_def 274 * in the BPF object file. 275 */ 276 LIBBPF_API struct bpf_map * 277 bpf_object__find_map_by_offset(struct bpf_object *obj, size_t offset); 278 279 LIBBPF_API struct bpf_map * 280 bpf_map__next(struct bpf_map *map, struct bpf_object *obj); 281 #define bpf_object__for_each_map(pos, obj) \ 282 for ((pos) = bpf_map__next(NULL, (obj)); \ 283 (pos) != NULL; \ 284 (pos) = bpf_map__next((pos), (obj))) 285 #define bpf_map__for_each bpf_object__for_each_map 286 287 LIBBPF_API struct bpf_map * 288 bpf_map__prev(struct bpf_map *map, struct bpf_object *obj); 289 290 LIBBPF_API int bpf_map__fd(struct bpf_map *map); 291 LIBBPF_API const struct bpf_map_def *bpf_map__def(struct bpf_map *map); 292 LIBBPF_API const char *bpf_map__name(struct bpf_map *map); 293 LIBBPF_API __u32 bpf_map__btf_key_type_id(const struct bpf_map *map); 294 LIBBPF_API __u32 bpf_map__btf_value_type_id(const struct bpf_map *map); 295 296 typedef void (*bpf_map_clear_priv_t)(struct bpf_map *, void *); 297 LIBBPF_API int bpf_map__set_priv(struct bpf_map *map, void *priv, 298 bpf_map_clear_priv_t clear_priv); 299 LIBBPF_API void *bpf_map__priv(struct bpf_map *map); 300 LIBBPF_API int bpf_map__reuse_fd(struct bpf_map *map, int fd); 301 LIBBPF_API int bpf_map__resize(struct bpf_map *map, __u32 max_entries); 302 LIBBPF_API bool bpf_map__is_offload_neutral(struct bpf_map *map); 303 LIBBPF_API void bpf_map__set_ifindex(struct bpf_map *map, __u32 ifindex); 304 LIBBPF_API int bpf_map__pin(struct bpf_map *map, const char *path); 305 LIBBPF_API int bpf_map__unpin(struct bpf_map *map, const char *path); 306 307 LIBBPF_API int bpf_map__set_inner_map_fd(struct bpf_map *map, int fd); 308 309 LIBBPF_API long libbpf_get_error(const void *ptr); 310 311 struct bpf_prog_load_attr { 312 const char *file; 313 enum bpf_prog_type prog_type; 314 enum bpf_attach_type expected_attach_type; 315 int ifindex; 316 }; 317 318 LIBBPF_API int bpf_prog_load_xattr(const struct bpf_prog_load_attr *attr, 319 struct bpf_object **pobj, int *prog_fd); 320 LIBBPF_API int bpf_prog_load(const char *file, enum bpf_prog_type type, 321 struct bpf_object **pobj, int *prog_fd); 322 323 LIBBPF_API int bpf_set_link_xdp_fd(int ifindex, int fd, __u32 flags); 324 LIBBPF_API int bpf_get_link_xdp_id(int ifindex, __u32 *prog_id, __u32 flags); 325 326 enum bpf_perf_event_ret { 327 LIBBPF_PERF_EVENT_DONE = 0, 328 LIBBPF_PERF_EVENT_ERROR = -1, 329 LIBBPF_PERF_EVENT_CONT = -2, 330 }; 331 332 struct perf_event_header; 333 typedef enum bpf_perf_event_ret 334 (*bpf_perf_event_print_t)(struct perf_event_header *hdr, 335 void *private_data); 336 LIBBPF_API enum bpf_perf_event_ret 337 bpf_perf_event_read_simple(void *mmap_mem, size_t mmap_size, size_t page_size, 338 void **copy_mem, size_t *copy_size, 339 bpf_perf_event_print_t fn, void *private_data); 340 341 struct nlattr; 342 typedef int (*libbpf_dump_nlmsg_t)(void *cookie, void *msg, struct nlattr **tb); 343 int libbpf_netlink_open(unsigned int *nl_pid); 344 int libbpf_nl_get_link(int sock, unsigned int nl_pid, 345 libbpf_dump_nlmsg_t dump_link_nlmsg, void *cookie); 346 int libbpf_nl_get_class(int sock, unsigned int nl_pid, int ifindex, 347 libbpf_dump_nlmsg_t dump_class_nlmsg, void *cookie); 348 int libbpf_nl_get_qdisc(int sock, unsigned int nl_pid, int ifindex, 349 libbpf_dump_nlmsg_t dump_qdisc_nlmsg, void *cookie); 350 int libbpf_nl_get_filter(int sock, unsigned int nl_pid, int ifindex, int handle, 351 libbpf_dump_nlmsg_t dump_filter_nlmsg, void *cookie); 352 353 struct bpf_prog_linfo; 354 struct bpf_prog_info; 355 356 LIBBPF_API void bpf_prog_linfo__free(struct bpf_prog_linfo *prog_linfo); 357 LIBBPF_API struct bpf_prog_linfo * 358 bpf_prog_linfo__new(const struct bpf_prog_info *info); 359 LIBBPF_API const struct bpf_line_info * 360 bpf_prog_linfo__lfind_addr_func(const struct bpf_prog_linfo *prog_linfo, 361 __u64 addr, __u32 func_idx, __u32 nr_skip); 362 LIBBPF_API const struct bpf_line_info * 363 bpf_prog_linfo__lfind(const struct bpf_prog_linfo *prog_linfo, 364 __u32 insn_off, __u32 nr_skip); 365 366 /* 367 * Probe for supported system features 368 * 369 * Note that running many of these probes in a short amount of time can cause 370 * the kernel to reach the maximal size of lockable memory allowed for the 371 * user, causing subsequent probes to fail. In this case, the caller may want 372 * to adjust that limit with setrlimit(). 373 */ 374 LIBBPF_API bool bpf_probe_prog_type(enum bpf_prog_type prog_type, 375 __u32 ifindex); 376 LIBBPF_API bool bpf_probe_map_type(enum bpf_map_type map_type, __u32 ifindex); 377 LIBBPF_API bool bpf_probe_helper(enum bpf_func_id id, 378 enum bpf_prog_type prog_type, __u32 ifindex); 379 380 #ifdef __cplusplus 381 } /* extern "C" */ 382 #endif 383 384 #endif /* __LIBBPF_LIBBPF_H */ 385