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 *bpf_object__open(const char *path);
70 struct bpf_object *bpf_object__open_buffer(void *obj_buf,
73 int bpf_object__pin(struct bpf_object *object, const char *path);
74 void bpf_object__close(struct bpf_object *object);
76 /* Load/unload object into/from kernel */
77 int bpf_object__load(struct bpf_object *obj);
78 int bpf_object__unload(struct bpf_object *obj);
79 const char *bpf_object__name(struct bpf_object *obj);
80 unsigned int bpf_object__kversion(struct bpf_object *obj);
81 int bpf_object__btf_fd(const struct bpf_object *obj);
83 struct bpf_object *bpf_object__next(struct bpf_object *prev);
84 #define bpf_object__for_each_safe(pos, tmp) \
85 for ((pos) = bpf_object__next(NULL), \
86 (tmp) = bpf_object__next(pos); \
88 (pos) = (tmp), (tmp) = bpf_object__next(tmp))
90 typedef void (*bpf_object_clear_priv_t)(struct bpf_object *, void *);
91 int bpf_object__set_priv(struct bpf_object *obj, void *priv,
92 bpf_object_clear_priv_t clear_priv);
93 void *bpf_object__priv(struct bpf_object *prog);
95 int libbpf_prog_type_by_name(const char *name, enum bpf_prog_type *prog_type,
96 enum bpf_attach_type *expected_attach_type);
98 /* Accessors of bpf_program */
100 struct bpf_program *bpf_program__next(struct bpf_program *prog,
101 struct bpf_object *obj);
103 #define bpf_object__for_each_program(pos, obj) \
104 for ((pos) = bpf_program__next(NULL, (obj)); \
106 (pos) = bpf_program__next((pos), (obj)))
108 typedef void (*bpf_program_clear_priv_t)(struct bpf_program *,
111 int bpf_program__set_priv(struct bpf_program *prog, void *priv,
112 bpf_program_clear_priv_t clear_priv);
114 void *bpf_program__priv(struct bpf_program *prog);
115 void bpf_program__set_ifindex(struct bpf_program *prog, __u32 ifindex);
117 const char *bpf_program__title(struct bpf_program *prog, bool needs_copy);
119 int bpf_program__fd(struct bpf_program *prog);
120 int bpf_program__pin_instance(struct bpf_program *prog, const char *path,
122 int bpf_program__pin(struct bpf_program *prog, const char *path);
127 * Libbpf allows callers to adjust BPF programs before being loaded
128 * into kernel. One program in an object file can be transformed into
129 * multiple variants to be attached to different hooks.
131 * bpf_program_prep_t, bpf_program__set_prep and bpf_program__nth_fd
132 * form an API for this purpose.
134 * - bpf_program_prep_t:
135 * Defines a 'preprocessor', which is a caller defined function
136 * passed to libbpf through bpf_program__set_prep(), and will be
137 * called before program is loaded. The processor should adjust
138 * the program one time for each instance according to the instance id
141 * - bpf_program__set_prep:
142 * Attaches a preprocessor to a BPF program. The number of instances
143 * that should be created is also passed through this function.
145 * - bpf_program__nth_fd:
146 * After the program is loaded, get resulting FD of a given instance
147 * of the BPF program.
149 * If bpf_program__set_prep() is not used, the program would be loaded
150 * without adjustment during bpf_object__load(). The program has only
151 * one instance. In this case bpf_program__fd(prog) is equal to
152 * bpf_program__nth_fd(prog, 0).
155 struct bpf_prog_prep_result {
157 * If not NULL, load new instruction array.
158 * If set to NULL, don't load this instance.
160 struct bpf_insn *new_insn_ptr;
163 /* If not NULL, result FD is written to it. */
168 * Parameters of bpf_program_prep_t:
169 * - prog: The bpf_program being loaded.
170 * - n: Index of instance being generated.
171 * - insns: BPF instructions array.
172 * - insns_cnt:Number of instructions in insns.
173 * - res: Output parameter, result of transformation.
176 * - Zero: pre-processing success.
177 * - Non-zero: pre-processing error, stop loading.
179 typedef int (*bpf_program_prep_t)(struct bpf_program *prog, int n,
180 struct bpf_insn *insns, int insns_cnt,
181 struct bpf_prog_prep_result *res);
183 int bpf_program__set_prep(struct bpf_program *prog, int nr_instance,
184 bpf_program_prep_t prep);
186 int bpf_program__nth_fd(struct bpf_program *prog, int n);
189 * Adjust type of BPF program. Default is kprobe.
191 int bpf_program__set_socket_filter(struct bpf_program *prog);
192 int bpf_program__set_tracepoint(struct bpf_program *prog);
193 int bpf_program__set_raw_tracepoint(struct bpf_program *prog);
194 int bpf_program__set_kprobe(struct bpf_program *prog);
195 int bpf_program__set_sched_cls(struct bpf_program *prog);
196 int bpf_program__set_sched_act(struct bpf_program *prog);
197 int bpf_program__set_xdp(struct bpf_program *prog);
198 int bpf_program__set_perf_event(struct bpf_program *prog);
199 void bpf_program__set_type(struct bpf_program *prog, enum bpf_prog_type type);
200 void bpf_program__set_expected_attach_type(struct bpf_program *prog,
201 enum bpf_attach_type type);
203 bool bpf_program__is_socket_filter(struct bpf_program *prog);
204 bool bpf_program__is_tracepoint(struct bpf_program *prog);
205 bool bpf_program__is_raw_tracepoint(struct bpf_program *prog);
206 bool bpf_program__is_kprobe(struct bpf_program *prog);
207 bool bpf_program__is_sched_cls(struct bpf_program *prog);
208 bool bpf_program__is_sched_act(struct bpf_program *prog);
209 bool bpf_program__is_xdp(struct bpf_program *prog);
210 bool bpf_program__is_perf_event(struct bpf_program *prog);
213 * No need for __attribute__((packed)), all members of 'bpf_map_def'
214 * are all aligned. In addition, using __attribute__((packed))
215 * would trigger a -Wpacked warning message, and lead to an error
220 unsigned int key_size;
221 unsigned int value_size;
222 unsigned int max_entries;
223 unsigned int map_flags;
227 * The 'struct bpf_map' in include/linux/bpf.h is internal to the kernel,
228 * so no need to worry about a name clash.
232 bpf_object__find_map_by_name(struct bpf_object *obj, const char *name);
235 * Get bpf_map through the offset of corresponding struct bpf_map_def
236 * in the BPF object file.
239 bpf_object__find_map_by_offset(struct bpf_object *obj, size_t offset);
242 bpf_map__next(struct bpf_map *map, struct bpf_object *obj);
243 #define bpf_map__for_each(pos, obj) \
244 for ((pos) = bpf_map__next(NULL, (obj)); \
246 (pos) = bpf_map__next((pos), (obj)))
248 int bpf_map__fd(struct bpf_map *map);
249 const struct bpf_map_def *bpf_map__def(struct bpf_map *map);
250 const char *bpf_map__name(struct bpf_map *map);
251 uint32_t bpf_map__btf_key_type_id(const struct bpf_map *map);
252 uint32_t bpf_map__btf_value_type_id(const struct bpf_map *map);
254 typedef void (*bpf_map_clear_priv_t)(struct bpf_map *, void *);
255 int bpf_map__set_priv(struct bpf_map *map, void *priv,
256 bpf_map_clear_priv_t clear_priv);
257 void *bpf_map__priv(struct bpf_map *map);
258 bool bpf_map__is_offload_neutral(struct bpf_map *map);
259 void bpf_map__set_ifindex(struct bpf_map *map, __u32 ifindex);
260 int bpf_map__pin(struct bpf_map *map, const char *path);
262 long libbpf_get_error(const void *ptr);
264 struct bpf_prog_load_attr {
266 enum bpf_prog_type prog_type;
267 enum bpf_attach_type expected_attach_type;
271 int bpf_prog_load_xattr(const struct bpf_prog_load_attr *attr,
272 struct bpf_object **pobj, int *prog_fd);
273 int bpf_prog_load(const char *file, enum bpf_prog_type type,
274 struct bpf_object **pobj, int *prog_fd);
276 int bpf_set_link_xdp_fd(int ifindex, int fd, __u32 flags);
278 enum bpf_perf_event_ret {
279 LIBBPF_PERF_EVENT_DONE = 0,
280 LIBBPF_PERF_EVENT_ERROR = -1,
281 LIBBPF_PERF_EVENT_CONT = -2,
284 typedef enum bpf_perf_event_ret (*bpf_perf_event_print_t)(void *event,
286 int bpf_perf_event_read_simple(void *mem, unsigned long size,
287 unsigned long page_size,
288 void **buf, size_t *buf_len,
289 bpf_perf_event_print_t fn, void *priv);