1 /* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */
4 * Common eBPF ELF object loading operations.
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.
10 #ifndef __LIBBPF_LIBBPF_H
11 #define __LIBBPF_LIBBPF_H
17 #include <sys/types.h> // for size_t
18 #include <linux/bpf.h>
25 #define LIBBPF_API __attribute__((visibility("default")))
29 __LIBBPF_ERRNO__START = 4000,
31 /* Something wrong in libelf */
32 LIBBPF_ERRNO__LIBELF = __LIBBPF_ERRNO__START,
33 LIBBPF_ERRNO__FORMAT, /* BPF object format invalid */
34 LIBBPF_ERRNO__KVERSION, /* Incorrect or no 'version' section */
35 LIBBPF_ERRNO__ENDIAN, /* Endian mismatch */
36 LIBBPF_ERRNO__INTERNAL, /* Internal error in libbpf */
37 LIBBPF_ERRNO__RELOC, /* Relocation failed */
38 LIBBPF_ERRNO__LOAD, /* Load program failure for unknown reason */
39 LIBBPF_ERRNO__VERIFY, /* Kernel verifier blocks program loading */
40 LIBBPF_ERRNO__PROG2BIG, /* Program too big */
41 LIBBPF_ERRNO__KVER, /* Incorrect kernel version */
42 LIBBPF_ERRNO__PROGTYPE, /* Kernel doesn't support this program type */
43 LIBBPF_ERRNO__WRNGPID, /* Wrong pid in netlink message */
44 LIBBPF_ERRNO__INVSEQ, /* Invalid netlink sequence */
45 LIBBPF_ERRNO__NLPARSE, /* netlink parsing error */
49 LIBBPF_API int libbpf_strerror(int err, char *buf, size_t size);
51 enum libbpf_print_level {
57 typedef int (*libbpf_print_fn_t)(enum libbpf_print_level level,
58 const char *, va_list ap);
60 LIBBPF_API libbpf_print_fn_t libbpf_set_print(libbpf_print_fn_t fn);
62 /* Hide internal to user */
65 struct bpf_object_open_attr {
67 enum bpf_prog_type prog_type;
70 LIBBPF_API struct bpf_object *bpf_object__open(const char *path);
71 LIBBPF_API struct bpf_object *
72 bpf_object__open_xattr(struct bpf_object_open_attr *attr);
73 struct bpf_object *__bpf_object__open_xattr(struct bpf_object_open_attr *attr,
75 LIBBPF_API struct bpf_object *bpf_object__open_buffer(void *obj_buf,
78 int bpf_object__section_size(const struct bpf_object *obj, const char *name,
80 int bpf_object__variable_offset(const struct bpf_object *obj, const char *name,
82 LIBBPF_API int bpf_object__pin_maps(struct bpf_object *obj, const char *path);
83 LIBBPF_API int bpf_object__unpin_maps(struct bpf_object *obj,
85 LIBBPF_API int bpf_object__pin_programs(struct bpf_object *obj,
87 LIBBPF_API int bpf_object__unpin_programs(struct bpf_object *obj,
89 LIBBPF_API int bpf_object__pin(struct bpf_object *object, const char *path);
90 LIBBPF_API void bpf_object__close(struct bpf_object *object);
92 struct bpf_object_load_attr {
93 struct bpf_object *obj;
95 const char *target_btf_path;
98 /* Load/unload object into/from kernel */
99 LIBBPF_API int bpf_object__load(struct bpf_object *obj);
100 LIBBPF_API int bpf_object__load_xattr(struct bpf_object_load_attr *attr);
101 LIBBPF_API int bpf_object__unload(struct bpf_object *obj);
102 LIBBPF_API const char *bpf_object__name(const struct bpf_object *obj);
103 LIBBPF_API unsigned int bpf_object__kversion(const struct bpf_object *obj);
106 LIBBPF_API struct btf *bpf_object__btf(const struct bpf_object *obj);
107 LIBBPF_API int bpf_object__btf_fd(const struct bpf_object *obj);
109 LIBBPF_API struct bpf_program *
110 bpf_object__find_program_by_title(const struct bpf_object *obj,
113 LIBBPF_API struct bpf_object *bpf_object__next(struct bpf_object *prev);
114 #define bpf_object__for_each_safe(pos, tmp) \
115 for ((pos) = bpf_object__next(NULL), \
116 (tmp) = bpf_object__next(pos); \
118 (pos) = (tmp), (tmp) = bpf_object__next(tmp))
120 typedef void (*bpf_object_clear_priv_t)(struct bpf_object *, void *);
121 LIBBPF_API int bpf_object__set_priv(struct bpf_object *obj, void *priv,
122 bpf_object_clear_priv_t clear_priv);
123 LIBBPF_API void *bpf_object__priv(const struct bpf_object *prog);
126 libbpf_prog_type_by_name(const char *name, enum bpf_prog_type *prog_type,
127 enum bpf_attach_type *expected_attach_type);
128 LIBBPF_API int libbpf_attach_type_by_name(const char *name,
129 enum bpf_attach_type *attach_type);
131 /* Accessors of bpf_program */
133 LIBBPF_API struct bpf_program *bpf_program__next(struct bpf_program *prog,
134 const struct bpf_object *obj);
136 #define bpf_object__for_each_program(pos, obj) \
137 for ((pos) = bpf_program__next(NULL, (obj)); \
139 (pos) = bpf_program__next((pos), (obj)))
141 LIBBPF_API struct bpf_program *bpf_program__prev(struct bpf_program *prog,
142 const struct bpf_object *obj);
144 typedef void (*bpf_program_clear_priv_t)(struct bpf_program *, void *);
146 LIBBPF_API int bpf_program__set_priv(struct bpf_program *prog, void *priv,
147 bpf_program_clear_priv_t clear_priv);
149 LIBBPF_API void *bpf_program__priv(const struct bpf_program *prog);
150 LIBBPF_API void bpf_program__set_ifindex(struct bpf_program *prog,
153 LIBBPF_API const char *bpf_program__title(const struct bpf_program *prog,
156 LIBBPF_API int bpf_program__load(struct bpf_program *prog, char *license,
158 LIBBPF_API int bpf_program__fd(const struct bpf_program *prog);
159 LIBBPF_API int bpf_program__pin_instance(struct bpf_program *prog,
162 LIBBPF_API int bpf_program__unpin_instance(struct bpf_program *prog,
165 LIBBPF_API int bpf_program__pin(struct bpf_program *prog, const char *path);
166 LIBBPF_API int bpf_program__unpin(struct bpf_program *prog, const char *path);
167 LIBBPF_API void bpf_program__unload(struct bpf_program *prog);
171 LIBBPF_API int bpf_link__destroy(struct bpf_link *link);
173 LIBBPF_API struct bpf_link *
174 bpf_program__attach_perf_event(struct bpf_program *prog, int pfd);
175 LIBBPF_API struct bpf_link *
176 bpf_program__attach_kprobe(struct bpf_program *prog, bool retprobe,
177 const char *func_name);
178 LIBBPF_API struct bpf_link *
179 bpf_program__attach_uprobe(struct bpf_program *prog, bool retprobe,
180 pid_t pid, const char *binary_path,
182 LIBBPF_API struct bpf_link *
183 bpf_program__attach_tracepoint(struct bpf_program *prog,
184 const char *tp_category,
185 const char *tp_name);
186 LIBBPF_API struct bpf_link *
187 bpf_program__attach_raw_tracepoint(struct bpf_program *prog,
188 const char *tp_name);
193 * Libbpf allows callers to adjust BPF programs before being loaded
194 * into kernel. One program in an object file can be transformed into
195 * multiple variants to be attached to different hooks.
197 * bpf_program_prep_t, bpf_program__set_prep and bpf_program__nth_fd
198 * form an API for this purpose.
200 * - bpf_program_prep_t:
201 * Defines a 'preprocessor', which is a caller defined function
202 * passed to libbpf through bpf_program__set_prep(), and will be
203 * called before program is loaded. The processor should adjust
204 * the program one time for each instance according to the instance id
207 * - bpf_program__set_prep:
208 * Attaches a preprocessor to a BPF program. The number of instances
209 * that should be created is also passed through this function.
211 * - bpf_program__nth_fd:
212 * After the program is loaded, get resulting FD of a given instance
213 * of the BPF program.
215 * If bpf_program__set_prep() is not used, the program would be loaded
216 * without adjustment during bpf_object__load(). The program has only
217 * one instance. In this case bpf_program__fd(prog) is equal to
218 * bpf_program__nth_fd(prog, 0).
221 struct bpf_prog_prep_result {
223 * If not NULL, load new instruction array.
224 * If set to NULL, don't load this instance.
226 struct bpf_insn *new_insn_ptr;
229 /* If not NULL, result FD is written to it. */
234 * Parameters of bpf_program_prep_t:
235 * - prog: The bpf_program being loaded.
236 * - n: Index of instance being generated.
237 * - insns: BPF instructions array.
238 * - insns_cnt:Number of instructions in insns.
239 * - res: Output parameter, result of transformation.
242 * - Zero: pre-processing success.
243 * - Non-zero: pre-processing error, stop loading.
245 typedef int (*bpf_program_prep_t)(struct bpf_program *prog, int n,
246 struct bpf_insn *insns, int insns_cnt,
247 struct bpf_prog_prep_result *res);
249 LIBBPF_API int bpf_program__set_prep(struct bpf_program *prog, int nr_instance,
250 bpf_program_prep_t prep);
252 LIBBPF_API int bpf_program__nth_fd(const struct bpf_program *prog, int n);
255 * Adjust type of BPF program. Default is kprobe.
257 LIBBPF_API int bpf_program__set_socket_filter(struct bpf_program *prog);
258 LIBBPF_API int bpf_program__set_tracepoint(struct bpf_program *prog);
259 LIBBPF_API int bpf_program__set_raw_tracepoint(struct bpf_program *prog);
260 LIBBPF_API int bpf_program__set_kprobe(struct bpf_program *prog);
261 LIBBPF_API int bpf_program__set_sched_cls(struct bpf_program *prog);
262 LIBBPF_API int bpf_program__set_sched_act(struct bpf_program *prog);
263 LIBBPF_API int bpf_program__set_xdp(struct bpf_program *prog);
264 LIBBPF_API int bpf_program__set_perf_event(struct bpf_program *prog);
265 LIBBPF_API void bpf_program__set_type(struct bpf_program *prog,
266 enum bpf_prog_type type);
268 bpf_program__set_expected_attach_type(struct bpf_program *prog,
269 enum bpf_attach_type type);
271 LIBBPF_API bool bpf_program__is_socket_filter(const struct bpf_program *prog);
272 LIBBPF_API bool bpf_program__is_tracepoint(const struct bpf_program *prog);
273 LIBBPF_API bool bpf_program__is_raw_tracepoint(const struct bpf_program *prog);
274 LIBBPF_API bool bpf_program__is_kprobe(const struct bpf_program *prog);
275 LIBBPF_API bool bpf_program__is_sched_cls(const struct bpf_program *prog);
276 LIBBPF_API bool bpf_program__is_sched_act(const struct bpf_program *prog);
277 LIBBPF_API bool bpf_program__is_xdp(const struct bpf_program *prog);
278 LIBBPF_API bool bpf_program__is_perf_event(const struct bpf_program *prog);
281 * No need for __attribute__((packed)), all members of 'bpf_map_def'
282 * are all aligned. In addition, using __attribute__((packed))
283 * would trigger a -Wpacked warning message, and lead to an error
288 unsigned int key_size;
289 unsigned int value_size;
290 unsigned int max_entries;
291 unsigned int map_flags;
295 * The 'struct bpf_map' in include/linux/bpf.h is internal to the kernel,
296 * so no need to worry about a name clash.
299 LIBBPF_API struct bpf_map *
300 bpf_object__find_map_by_name(const struct bpf_object *obj, const char *name);
303 bpf_object__find_map_fd_by_name(const struct bpf_object *obj, const char *name);
306 * Get bpf_map through the offset of corresponding struct bpf_map_def
307 * in the BPF object file.
309 LIBBPF_API struct bpf_map *
310 bpf_object__find_map_by_offset(struct bpf_object *obj, size_t offset);
312 LIBBPF_API struct bpf_map *
313 bpf_map__next(const struct bpf_map *map, const struct bpf_object *obj);
314 #define bpf_object__for_each_map(pos, obj) \
315 for ((pos) = bpf_map__next(NULL, (obj)); \
317 (pos) = bpf_map__next((pos), (obj)))
318 #define bpf_map__for_each bpf_object__for_each_map
320 LIBBPF_API struct bpf_map *
321 bpf_map__prev(const struct bpf_map *map, const struct bpf_object *obj);
323 LIBBPF_API int bpf_map__fd(const struct bpf_map *map);
324 LIBBPF_API const struct bpf_map_def *bpf_map__def(const struct bpf_map *map);
325 LIBBPF_API const char *bpf_map__name(const struct bpf_map *map);
326 LIBBPF_API __u32 bpf_map__btf_key_type_id(const struct bpf_map *map);
327 LIBBPF_API __u32 bpf_map__btf_value_type_id(const struct bpf_map *map);
329 typedef void (*bpf_map_clear_priv_t)(struct bpf_map *, void *);
330 LIBBPF_API int bpf_map__set_priv(struct bpf_map *map, void *priv,
331 bpf_map_clear_priv_t clear_priv);
332 LIBBPF_API void *bpf_map__priv(const struct bpf_map *map);
333 LIBBPF_API int bpf_map__reuse_fd(struct bpf_map *map, int fd);
334 LIBBPF_API int bpf_map__resize(struct bpf_map *map, __u32 max_entries);
335 LIBBPF_API bool bpf_map__is_offload_neutral(const struct bpf_map *map);
336 LIBBPF_API bool bpf_map__is_internal(const struct bpf_map *map);
337 LIBBPF_API void bpf_map__set_ifindex(struct bpf_map *map, __u32 ifindex);
338 LIBBPF_API int bpf_map__pin(struct bpf_map *map, const char *path);
339 LIBBPF_API int bpf_map__unpin(struct bpf_map *map, const char *path);
341 LIBBPF_API int bpf_map__set_inner_map_fd(struct bpf_map *map, int fd);
343 LIBBPF_API long libbpf_get_error(const void *ptr);
345 struct bpf_prog_load_attr {
347 enum bpf_prog_type prog_type;
348 enum bpf_attach_type expected_attach_type;
354 LIBBPF_API int bpf_prog_load_xattr(const struct bpf_prog_load_attr *attr,
355 struct bpf_object **pobj, int *prog_fd);
356 LIBBPF_API int bpf_prog_load(const char *file, enum bpf_prog_type type,
357 struct bpf_object **pobj, int *prog_fd);
359 LIBBPF_API int bpf_set_link_xdp_fd(int ifindex, int fd, __u32 flags);
360 LIBBPF_API int bpf_get_link_xdp_id(int ifindex, __u32 *prog_id, __u32 flags);
364 typedef void (*perf_buffer_sample_fn)(void *ctx, int cpu,
365 void *data, __u32 size);
366 typedef void (*perf_buffer_lost_fn)(void *ctx, int cpu, __u64 cnt);
368 /* common use perf buffer options */
369 struct perf_buffer_opts {
370 /* if specified, sample_cb is called for each sample */
371 perf_buffer_sample_fn sample_cb;
372 /* if specified, lost_cb is called for each batch of lost samples */
373 perf_buffer_lost_fn lost_cb;
374 /* ctx is provided to sample_cb and lost_cb */
378 LIBBPF_API struct perf_buffer *
379 perf_buffer__new(int map_fd, size_t page_cnt,
380 const struct perf_buffer_opts *opts);
382 enum bpf_perf_event_ret {
383 LIBBPF_PERF_EVENT_DONE = 0,
384 LIBBPF_PERF_EVENT_ERROR = -1,
385 LIBBPF_PERF_EVENT_CONT = -2,
388 struct perf_event_header;
390 typedef enum bpf_perf_event_ret
391 (*perf_buffer_event_fn)(void *ctx, int cpu, struct perf_event_header *event);
393 /* raw perf buffer options, giving most power and control */
394 struct perf_buffer_raw_opts {
395 /* perf event attrs passed directly into perf_event_open() */
396 struct perf_event_attr *attr;
397 /* raw event callback */
398 perf_buffer_event_fn event_cb;
399 /* ctx is provided to event_cb */
401 /* if cpu_cnt == 0, open all on all possible CPUs (up to the number of
402 * max_entries of given PERF_EVENT_ARRAY map)
405 /* if cpu_cnt > 0, cpus is an array of CPUs to open ring buffers on */
407 /* if cpu_cnt > 0, map_keys specify map keys to set per-CPU FDs for */
411 LIBBPF_API struct perf_buffer *
412 perf_buffer__new_raw(int map_fd, size_t page_cnt,
413 const struct perf_buffer_raw_opts *opts);
415 LIBBPF_API void perf_buffer__free(struct perf_buffer *pb);
416 LIBBPF_API int perf_buffer__poll(struct perf_buffer *pb, int timeout_ms);
418 typedef enum bpf_perf_event_ret
419 (*bpf_perf_event_print_t)(struct perf_event_header *hdr,
421 LIBBPF_API enum bpf_perf_event_ret
422 bpf_perf_event_read_simple(void *mmap_mem, size_t mmap_size, size_t page_size,
423 void **copy_mem, size_t *copy_size,
424 bpf_perf_event_print_t fn, void *private_data);
427 typedef int (*libbpf_dump_nlmsg_t)(void *cookie, void *msg, struct nlattr **tb);
428 int libbpf_netlink_open(unsigned int *nl_pid);
429 int libbpf_nl_get_link(int sock, unsigned int nl_pid,
430 libbpf_dump_nlmsg_t dump_link_nlmsg, void *cookie);
431 int libbpf_nl_get_class(int sock, unsigned int nl_pid, int ifindex,
432 libbpf_dump_nlmsg_t dump_class_nlmsg, void *cookie);
433 int libbpf_nl_get_qdisc(int sock, unsigned int nl_pid, int ifindex,
434 libbpf_dump_nlmsg_t dump_qdisc_nlmsg, void *cookie);
435 int libbpf_nl_get_filter(int sock, unsigned int nl_pid, int ifindex, int handle,
436 libbpf_dump_nlmsg_t dump_filter_nlmsg, void *cookie);
438 struct bpf_prog_linfo;
439 struct bpf_prog_info;
441 LIBBPF_API void bpf_prog_linfo__free(struct bpf_prog_linfo *prog_linfo);
442 LIBBPF_API struct bpf_prog_linfo *
443 bpf_prog_linfo__new(const struct bpf_prog_info *info);
444 LIBBPF_API const struct bpf_line_info *
445 bpf_prog_linfo__lfind_addr_func(const struct bpf_prog_linfo *prog_linfo,
446 __u64 addr, __u32 func_idx, __u32 nr_skip);
447 LIBBPF_API const struct bpf_line_info *
448 bpf_prog_linfo__lfind(const struct bpf_prog_linfo *prog_linfo,
449 __u32 insn_off, __u32 nr_skip);
452 * Probe for supported system features
454 * Note that running many of these probes in a short amount of time can cause
455 * the kernel to reach the maximal size of lockable memory allowed for the
456 * user, causing subsequent probes to fail. In this case, the caller may want
457 * to adjust that limit with setrlimit().
459 LIBBPF_API bool bpf_probe_prog_type(enum bpf_prog_type prog_type,
461 LIBBPF_API bool bpf_probe_map_type(enum bpf_map_type map_type, __u32 ifindex);
462 LIBBPF_API bool bpf_probe_helper(enum bpf_func_id id,
463 enum bpf_prog_type prog_type, __u32 ifindex);
466 * Get bpf_prog_info in continuous memory
468 * struct bpf_prog_info has multiple arrays. The user has option to choose
469 * arrays to fetch from kernel. The following APIs provide an uniform way to
470 * fetch these data. All arrays in bpf_prog_info are stored in a single
471 * continuous memory region. This makes it easy to store the info in a
474 * Before writing bpf_prog_info_linear to files, it is necessary to
475 * translate pointers in bpf_prog_info to offsets. Helper functions
476 * bpf_program__bpil_addr_to_offs() and bpf_program__bpil_offs_to_addr()
477 * are introduced to switch between pointers and offsets.
480 * # To fetch map_ids and prog_tags:
481 * __u64 arrays = (1UL << BPF_PROG_INFO_MAP_IDS) |
482 * (1UL << BPF_PROG_INFO_PROG_TAGS);
483 * struct bpf_prog_info_linear *info_linear =
484 * bpf_program__get_prog_info_linear(fd, arrays);
486 * # To save data in file
487 * bpf_program__bpil_addr_to_offs(info_linear);
488 * write(f, info_linear, sizeof(*info_linear) + info_linear->data_len);
490 * # To read data from file
491 * read(f, info_linear, <proper_size>);
492 * bpf_program__bpil_offs_to_addr(info_linear);
494 enum bpf_prog_info_array {
495 BPF_PROG_INFO_FIRST_ARRAY = 0,
496 BPF_PROG_INFO_JITED_INSNS = 0,
497 BPF_PROG_INFO_XLATED_INSNS,
498 BPF_PROG_INFO_MAP_IDS,
499 BPF_PROG_INFO_JITED_KSYMS,
500 BPF_PROG_INFO_JITED_FUNC_LENS,
501 BPF_PROG_INFO_FUNC_INFO,
502 BPF_PROG_INFO_LINE_INFO,
503 BPF_PROG_INFO_JITED_LINE_INFO,
504 BPF_PROG_INFO_PROG_TAGS,
505 BPF_PROG_INFO_LAST_ARRAY,
508 struct bpf_prog_info_linear {
509 /* size of struct bpf_prog_info, when the tool is compiled */
511 /* total bytes allocated for data, round up to 8 bytes */
513 /* which arrays are included in data */
515 struct bpf_prog_info info;
519 LIBBPF_API struct bpf_prog_info_linear *
520 bpf_program__get_prog_info_linear(int fd, __u64 arrays);
523 bpf_program__bpil_addr_to_offs(struct bpf_prog_info_linear *info_linear);
526 bpf_program__bpil_offs_to_addr(struct bpf_prog_info_linear *info_linear);
529 * A helper function to get the number of possible CPUs before looking up
530 * per-CPU maps. Negative errno is returned on failure.
534 * int ncpus = libbpf_num_possible_cpus();
538 * long values[ncpus];
539 * bpf_map_lookup_elem(per_cpu_map_fd, key, values);
542 LIBBPF_API int libbpf_num_possible_cpus(void);
548 #endif /* __LIBBPF_LIBBPF_H */