1 /* SPDX-License-Identifier: LGPL-2.1 */
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 * This program is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU Lesser General Public
12 * License as published by the Free Software Foundation;
13 * version 2.1 of the License (not later!)
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU Lesser General Public License for more details.
20 * You should have received a copy of the GNU Lesser General Public
21 * License along with this program; if not, see <http://www.gnu.org/licenses>
23 #ifndef __BPF_LIBBPF_H
24 #define __BPF_LIBBPF_H
29 #include <sys/types.h> // for size_t
30 #include <linux/bpf.h>
33 __LIBBPF_ERRNO__START = 4000,
35 /* Something wrong in libelf */
36 LIBBPF_ERRNO__LIBELF = __LIBBPF_ERRNO__START,
37 LIBBPF_ERRNO__FORMAT, /* BPF object format invalid */
38 LIBBPF_ERRNO__KVERSION, /* Incorrect or no 'version' section */
39 LIBBPF_ERRNO__ENDIAN, /* Endian mismatch */
40 LIBBPF_ERRNO__INTERNAL, /* Internal error in libbpf */
41 LIBBPF_ERRNO__RELOC, /* Relocation failed */
42 LIBBPF_ERRNO__LOAD, /* Load program failure for unknown reason */
43 LIBBPF_ERRNO__VERIFY, /* Kernel verifier blocks program loading */
44 LIBBPF_ERRNO__PROG2BIG, /* Program too big */
45 LIBBPF_ERRNO__KVER, /* Incorrect kernel version */
46 LIBBPF_ERRNO__PROGTYPE, /* Kernel doesn't support this program type */
47 LIBBPF_ERRNO__WRNGPID, /* Wrong pid in netlink message */
48 LIBBPF_ERRNO__INVSEQ, /* Invalid netlink sequence */
52 int libbpf_strerror(int err, char *buf, size_t size);
55 * __printf is defined in include/linux/compiler-gcc.h. However,
56 * it would be better if libbpf.h didn't depend on Linux header files.
57 * So instead of __printf, here we use gcc attribute directly.
59 typedef int (*libbpf_print_fn_t)(const char *, ...)
60 __attribute__((format(printf, 1, 2)));
62 void libbpf_set_print(libbpf_print_fn_t warn,
63 libbpf_print_fn_t info,
64 libbpf_print_fn_t debug);
66 /* Hide internal to user */
69 struct bpf_object_open_attr {
71 enum bpf_prog_type prog_type;
74 struct bpf_object *bpf_object__open(const char *path);
75 struct bpf_object *bpf_object__open_xattr(struct bpf_object_open_attr *attr);
76 struct bpf_object *bpf_object__open_buffer(void *obj_buf,
79 int bpf_object__pin(struct bpf_object *object, const char *path);
80 void bpf_object__close(struct bpf_object *object);
82 /* Load/unload object into/from kernel */
83 int bpf_object__load(struct bpf_object *obj);
84 int bpf_object__unload(struct bpf_object *obj);
85 const char *bpf_object__name(struct bpf_object *obj);
86 unsigned int bpf_object__kversion(struct bpf_object *obj);
87 int bpf_object__btf_fd(const struct bpf_object *obj);
90 bpf_object__find_program_by_title(struct bpf_object *obj, const char *title);
92 struct bpf_object *bpf_object__next(struct bpf_object *prev);
93 #define bpf_object__for_each_safe(pos, tmp) \
94 for ((pos) = bpf_object__next(NULL), \
95 (tmp) = bpf_object__next(pos); \
97 (pos) = (tmp), (tmp) = bpf_object__next(tmp))
99 typedef void (*bpf_object_clear_priv_t)(struct bpf_object *, void *);
100 int bpf_object__set_priv(struct bpf_object *obj, void *priv,
101 bpf_object_clear_priv_t clear_priv);
102 void *bpf_object__priv(struct bpf_object *prog);
104 int libbpf_prog_type_by_name(const char *name, enum bpf_prog_type *prog_type,
105 enum bpf_attach_type *expected_attach_type);
107 /* Accessors of bpf_program */
109 struct bpf_program *bpf_program__next(struct bpf_program *prog,
110 struct bpf_object *obj);
112 #define bpf_object__for_each_program(pos, obj) \
113 for ((pos) = bpf_program__next(NULL, (obj)); \
115 (pos) = bpf_program__next((pos), (obj)))
117 typedef void (*bpf_program_clear_priv_t)(struct bpf_program *,
120 int bpf_program__set_priv(struct bpf_program *prog, void *priv,
121 bpf_program_clear_priv_t clear_priv);
123 void *bpf_program__priv(struct bpf_program *prog);
124 void bpf_program__set_ifindex(struct bpf_program *prog, __u32 ifindex);
126 const char *bpf_program__title(struct bpf_program *prog, bool needs_copy);
128 int bpf_program__fd(struct bpf_program *prog);
129 int bpf_program__pin_instance(struct bpf_program *prog, const char *path,
131 int bpf_program__pin(struct bpf_program *prog, const char *path);
136 * Libbpf allows callers to adjust BPF programs before being loaded
137 * into kernel. One program in an object file can be transformed into
138 * multiple variants to be attached to different hooks.
140 * bpf_program_prep_t, bpf_program__set_prep and bpf_program__nth_fd
141 * form an API for this purpose.
143 * - bpf_program_prep_t:
144 * Defines a 'preprocessor', which is a caller defined function
145 * passed to libbpf through bpf_program__set_prep(), and will be
146 * called before program is loaded. The processor should adjust
147 * the program one time for each instance according to the instance id
150 * - bpf_program__set_prep:
151 * Attaches a preprocessor to a BPF program. The number of instances
152 * that should be created is also passed through this function.
154 * - bpf_program__nth_fd:
155 * After the program is loaded, get resulting FD of a given instance
156 * of the BPF program.
158 * If bpf_program__set_prep() is not used, the program would be loaded
159 * without adjustment during bpf_object__load(). The program has only
160 * one instance. In this case bpf_program__fd(prog) is equal to
161 * bpf_program__nth_fd(prog, 0).
164 struct bpf_prog_prep_result {
166 * If not NULL, load new instruction array.
167 * If set to NULL, don't load this instance.
169 struct bpf_insn *new_insn_ptr;
172 /* If not NULL, result FD is written to it. */
177 * Parameters of bpf_program_prep_t:
178 * - prog: The bpf_program being loaded.
179 * - n: Index of instance being generated.
180 * - insns: BPF instructions array.
181 * - insns_cnt:Number of instructions in insns.
182 * - res: Output parameter, result of transformation.
185 * - Zero: pre-processing success.
186 * - Non-zero: pre-processing error, stop loading.
188 typedef int (*bpf_program_prep_t)(struct bpf_program *prog, int n,
189 struct bpf_insn *insns, int insns_cnt,
190 struct bpf_prog_prep_result *res);
192 int bpf_program__set_prep(struct bpf_program *prog, int nr_instance,
193 bpf_program_prep_t prep);
195 int bpf_program__nth_fd(struct bpf_program *prog, int n);
198 * Adjust type of BPF program. Default is kprobe.
200 int bpf_program__set_socket_filter(struct bpf_program *prog);
201 int bpf_program__set_tracepoint(struct bpf_program *prog);
202 int bpf_program__set_raw_tracepoint(struct bpf_program *prog);
203 int bpf_program__set_kprobe(struct bpf_program *prog);
204 int bpf_program__set_sched_cls(struct bpf_program *prog);
205 int bpf_program__set_sched_act(struct bpf_program *prog);
206 int bpf_program__set_xdp(struct bpf_program *prog);
207 int bpf_program__set_perf_event(struct bpf_program *prog);
208 void bpf_program__set_type(struct bpf_program *prog, enum bpf_prog_type type);
209 void bpf_program__set_expected_attach_type(struct bpf_program *prog,
210 enum bpf_attach_type type);
212 bool bpf_program__is_socket_filter(struct bpf_program *prog);
213 bool bpf_program__is_tracepoint(struct bpf_program *prog);
214 bool bpf_program__is_raw_tracepoint(struct bpf_program *prog);
215 bool bpf_program__is_kprobe(struct bpf_program *prog);
216 bool bpf_program__is_sched_cls(struct bpf_program *prog);
217 bool bpf_program__is_sched_act(struct bpf_program *prog);
218 bool bpf_program__is_xdp(struct bpf_program *prog);
219 bool bpf_program__is_perf_event(struct bpf_program *prog);
222 * No need for __attribute__((packed)), all members of 'bpf_map_def'
223 * are all aligned. In addition, using __attribute__((packed))
224 * would trigger a -Wpacked warning message, and lead to an error
229 unsigned int key_size;
230 unsigned int value_size;
231 unsigned int max_entries;
232 unsigned int map_flags;
236 * The 'struct bpf_map' in include/linux/bpf.h is internal to the kernel,
237 * so no need to worry about a name clash.
241 bpf_object__find_map_by_name(struct bpf_object *obj, const char *name);
244 * Get bpf_map through the offset of corresponding struct bpf_map_def
245 * in the BPF object file.
248 bpf_object__find_map_by_offset(struct bpf_object *obj, size_t offset);
251 bpf_map__next(struct bpf_map *map, struct bpf_object *obj);
252 #define bpf_map__for_each(pos, obj) \
253 for ((pos) = bpf_map__next(NULL, (obj)); \
255 (pos) = bpf_map__next((pos), (obj)))
257 int bpf_map__fd(struct bpf_map *map);
258 const struct bpf_map_def *bpf_map__def(struct bpf_map *map);
259 const char *bpf_map__name(struct bpf_map *map);
260 __u32 bpf_map__btf_key_type_id(const struct bpf_map *map);
261 __u32 bpf_map__btf_value_type_id(const struct bpf_map *map);
263 typedef void (*bpf_map_clear_priv_t)(struct bpf_map *, void *);
264 int bpf_map__set_priv(struct bpf_map *map, void *priv,
265 bpf_map_clear_priv_t clear_priv);
266 void *bpf_map__priv(struct bpf_map *map);
267 int bpf_map__reuse_fd(struct bpf_map *map, int fd);
268 bool bpf_map__is_offload_neutral(struct bpf_map *map);
269 void bpf_map__set_ifindex(struct bpf_map *map, __u32 ifindex);
270 int bpf_map__pin(struct bpf_map *map, const char *path);
272 long libbpf_get_error(const void *ptr);
274 struct bpf_prog_load_attr {
276 enum bpf_prog_type prog_type;
277 enum bpf_attach_type expected_attach_type;
281 int bpf_prog_load_xattr(const struct bpf_prog_load_attr *attr,
282 struct bpf_object **pobj, int *prog_fd);
283 int bpf_prog_load(const char *file, enum bpf_prog_type type,
284 struct bpf_object **pobj, int *prog_fd);
286 int bpf_set_link_xdp_fd(int ifindex, int fd, __u32 flags);
288 enum bpf_perf_event_ret {
289 LIBBPF_PERF_EVENT_DONE = 0,
290 LIBBPF_PERF_EVENT_ERROR = -1,
291 LIBBPF_PERF_EVENT_CONT = -2,
294 typedef enum bpf_perf_event_ret (*bpf_perf_event_print_t)(void *event,
296 int bpf_perf_event_read_simple(void *mem, unsigned long size,
297 unsigned long page_size,
298 void **buf, size_t *buf_len,
299 bpf_perf_event_print_t fn, void *priv);