xref: /linux/tools/lib/bpf/bpf.h (revision 2363088eba2ecccfb643725e4864af73c4226a04)
1 /* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */
2 
3 /*
4  * Common BPF ELF 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  * 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!)
14  *
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.
19  *
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>
22  */
23 #ifndef __LIBBPF_BPF_H
24 #define __LIBBPF_BPF_H
25 
26 #include <linux/bpf.h>
27 #include <stdbool.h>
28 #include <stddef.h>
29 #include <stdint.h>
30 
31 #include "libbpf_common.h"
32 #include "libbpf_legacy.h"
33 
34 #ifdef __cplusplus
35 extern "C" {
36 #endif
37 
38 int libbpf_set_memlock_rlim(size_t memlock_bytes);
39 
40 struct bpf_map_create_opts {
41 	size_t sz; /* size of this struct for forward/backward compatibility */
42 
43 	__u32 btf_fd;
44 	__u32 btf_key_type_id;
45 	__u32 btf_value_type_id;
46 	__u32 btf_vmlinux_value_type_id;
47 
48 	__u32 inner_map_fd;
49 	__u32 map_flags;
50 	__u64 map_extra;
51 
52 	__u32 numa_node;
53 	__u32 map_ifindex;
54 };
55 #define bpf_map_create_opts__last_field map_ifindex
56 
57 LIBBPF_API int bpf_map_create(enum bpf_map_type map_type,
58 			      const char *map_name,
59 			      __u32 key_size,
60 			      __u32 value_size,
61 			      __u32 max_entries,
62 			      const struct bpf_map_create_opts *opts);
63 
64 struct bpf_prog_load_opts {
65 	size_t sz; /* size of this struct for forward/backward compatibility */
66 
67 	/* libbpf can retry BPF_PROG_LOAD command if bpf() syscall returns
68 	 * -EAGAIN. This field determines how many attempts libbpf has to
69 	 *  make. If not specified, libbpf will use default value of 5.
70 	 */
71 	int attempts;
72 
73 	enum bpf_attach_type expected_attach_type;
74 	__u32 prog_btf_fd;
75 	__u32 prog_flags;
76 	__u32 prog_ifindex;
77 	__u32 kern_version;
78 
79 	__u32 attach_btf_id;
80 	__u32 attach_prog_fd;
81 	__u32 attach_btf_obj_fd;
82 
83 	const int *fd_array;
84 
85 	/* .BTF.ext func info data */
86 	const void *func_info;
87 	__u32 func_info_cnt;
88 	__u32 func_info_rec_size;
89 
90 	/* .BTF.ext line info data */
91 	const void *line_info;
92 	__u32 line_info_cnt;
93 	__u32 line_info_rec_size;
94 
95 	/* verifier log options */
96 	__u32 log_level;
97 	__u32 log_size;
98 	char *log_buf;
99 	/* output: actual total log contents size (including termintaing zero).
100 	 * It could be both larger than original log_size (if log was
101 	 * truncated), or smaller (if log buffer wasn't filled completely).
102 	 * If kernel doesn't support this feature, log_size is left unchanged.
103 	 */
104 	__u32 log_true_size;
105 	size_t :0;
106 };
107 #define bpf_prog_load_opts__last_field log_true_size
108 
109 LIBBPF_API int bpf_prog_load(enum bpf_prog_type prog_type,
110 			     const char *prog_name, const char *license,
111 			     const struct bpf_insn *insns, size_t insn_cnt,
112 			     struct bpf_prog_load_opts *opts);
113 
114 /* Flags to direct loading requirements */
115 #define MAPS_RELAX_COMPAT	0x01
116 
117 /* Recommended log buffer size */
118 #define BPF_LOG_BUF_SIZE (UINT32_MAX >> 8) /* verifier maximum in kernels <= 5.1 */
119 
120 struct bpf_btf_load_opts {
121 	size_t sz; /* size of this struct for forward/backward compatibility */
122 
123 	/* kernel log options */
124 	char *log_buf;
125 	__u32 log_level;
126 	__u32 log_size;
127 	/* output: actual total log contents size (including termintaing zero).
128 	 * It could be both larger than original log_size (if log was
129 	 * truncated), or smaller (if log buffer wasn't filled completely).
130 	 * If kernel doesn't support this feature, log_size is left unchanged.
131 	 */
132 	__u32 log_true_size;
133 	size_t :0;
134 };
135 #define bpf_btf_load_opts__last_field log_true_size
136 
137 LIBBPF_API int bpf_btf_load(const void *btf_data, size_t btf_size,
138 			    struct bpf_btf_load_opts *opts);
139 
140 LIBBPF_API int bpf_map_update_elem(int fd, const void *key, const void *value,
141 				   __u64 flags);
142 
143 LIBBPF_API int bpf_map_lookup_elem(int fd, const void *key, void *value);
144 LIBBPF_API int bpf_map_lookup_elem_flags(int fd, const void *key, void *value,
145 					 __u64 flags);
146 LIBBPF_API int bpf_map_lookup_and_delete_elem(int fd, const void *key,
147 					      void *value);
148 LIBBPF_API int bpf_map_lookup_and_delete_elem_flags(int fd, const void *key,
149 						    void *value, __u64 flags);
150 LIBBPF_API int bpf_map_delete_elem(int fd, const void *key);
151 LIBBPF_API int bpf_map_delete_elem_flags(int fd, const void *key, __u64 flags);
152 LIBBPF_API int bpf_map_get_next_key(int fd, const void *key, void *next_key);
153 LIBBPF_API int bpf_map_freeze(int fd);
154 
155 struct bpf_map_batch_opts {
156 	size_t sz; /* size of this struct for forward/backward compatibility */
157 	__u64 elem_flags;
158 	__u64 flags;
159 };
160 #define bpf_map_batch_opts__last_field flags
161 
162 
163 /**
164  * @brief **bpf_map_delete_batch()** allows for batch deletion of multiple
165  * elements in a BPF map.
166  *
167  * @param fd BPF map file descriptor
168  * @param keys pointer to an array of *count* keys
169  * @param count input and output parameter; on input **count** represents the
170  * number of  elements in the map to delete in batch;
171  * on output if a non-EFAULT error is returned, **count** represents the number of deleted
172  * elements if the output **count** value is not equal to the input **count** value
173  * If EFAULT is returned, **count** should not be trusted to be correct.
174  * @param opts options for configuring the way the batch deletion works
175  * @return 0, on success; negative error code, otherwise (errno is also set to
176  * the error code)
177  */
178 LIBBPF_API int bpf_map_delete_batch(int fd, const void *keys,
179 				    __u32 *count,
180 				    const struct bpf_map_batch_opts *opts);
181 
182 /**
183  * @brief **bpf_map_lookup_batch()** allows for batch lookup of BPF map elements.
184  *
185  * The parameter *in_batch* is the address of the first element in the batch to read.
186  * *out_batch* is an output parameter that should be passed as *in_batch* to subsequent
187  * calls to **bpf_map_lookup_batch()**. NULL can be passed for *in_batch* to indicate
188  * that the batched lookup starts from the beginning of the map.
189  *
190  * The *keys* and *values* are output parameters which must point to memory large enough to
191  * hold *count* items based on the key and value size of the map *map_fd*. The *keys*
192  * buffer must be of *key_size* * *count*. The *values* buffer must be of
193  * *value_size* * *count*.
194  *
195  * @param fd BPF map file descriptor
196  * @param in_batch address of the first element in batch to read, can pass NULL to
197  * indicate that the batched lookup starts from the beginning of the map.
198  * @param out_batch output parameter that should be passed to next call as *in_batch*
199  * @param keys pointer to an array large enough for *count* keys
200  * @param values pointer to an array large enough for *count* values
201  * @param count input and output parameter; on input it's the number of elements
202  * in the map to read in batch; on output it's the number of elements that were
203  * successfully read.
204  * If a non-EFAULT error is returned, count will be set as the number of elements
205  * that were read before the error occurred.
206  * If EFAULT is returned, **count** should not be trusted to be correct.
207  * @param opts options for configuring the way the batch lookup works
208  * @return 0, on success; negative error code, otherwise (errno is also set to
209  * the error code)
210  */
211 LIBBPF_API int bpf_map_lookup_batch(int fd, void *in_batch, void *out_batch,
212 				    void *keys, void *values, __u32 *count,
213 				    const struct bpf_map_batch_opts *opts);
214 
215 /**
216  * @brief **bpf_map_lookup_and_delete_batch()** allows for batch lookup and deletion
217  * of BPF map elements where each element is deleted after being retrieved.
218  *
219  * @param fd BPF map file descriptor
220  * @param in_batch address of the first element in batch to read, can pass NULL to
221  * get address of the first element in *out_batch*
222  * @param out_batch output parameter that should be passed to next call as *in_batch*
223  * @param keys pointer to an array of *count* keys
224  * @param values pointer to an array large enough for *count* values
225  * @param count input and output parameter; on input it's the number of elements
226  * in the map to read and delete in batch; on output it represents the number of
227  * elements that were successfully read and deleted
228  * If a non-**EFAULT** error code is returned and if the output **count** value
229  * is not equal to the input **count** value, up to **count** elements may
230  * have been deleted.
231  * if **EFAULT** is returned up to *count* elements may have been deleted without
232  * being returned via the *keys* and *values* output parameters.
233  * @param opts options for configuring the way the batch lookup and delete works
234  * @return 0, on success; negative error code, otherwise (errno is also set to
235  * the error code)
236  */
237 LIBBPF_API int bpf_map_lookup_and_delete_batch(int fd, void *in_batch,
238 					void *out_batch, void *keys,
239 					void *values, __u32 *count,
240 					const struct bpf_map_batch_opts *opts);
241 
242 /**
243  * @brief **bpf_map_update_batch()** updates multiple elements in a map
244  * by specifying keys and their corresponding values.
245  *
246  * The *keys* and *values* parameters must point to memory large enough
247  * to hold *count* items based on the key and value size of the map.
248  *
249  * The *opts* parameter can be used to control how *bpf_map_update_batch()*
250  * should handle keys that either do or do not already exist in the map.
251  * In particular the *flags* parameter of *bpf_map_batch_opts* can be
252  * one of the following:
253  *
254  * Note that *count* is an input and output parameter, where on output it
255  * represents how many elements were successfully updated. Also note that if
256  * **EFAULT** then *count* should not be trusted to be correct.
257  *
258  * **BPF_ANY**
259  *    Create new elements or update existing.
260  *
261  * **BPF_NOEXIST**
262  *    Create new elements only if they do not exist.
263  *
264  * **BPF_EXIST**
265  *    Update existing elements.
266  *
267  * **BPF_F_LOCK**
268  *    Update spin_lock-ed map elements. This must be
269  *    specified if the map value contains a spinlock.
270  *
271  * @param fd BPF map file descriptor
272  * @param keys pointer to an array of *count* keys
273  * @param values pointer to an array of *count* values
274  * @param count input and output parameter; on input it's the number of elements
275  * in the map to update in batch; on output if a non-EFAULT error is returned,
276  * **count** represents the number of updated elements if the output **count**
277  * value is not equal to the input **count** value.
278  * If EFAULT is returned, **count** should not be trusted to be correct.
279  * @param opts options for configuring the way the batch update works
280  * @return 0, on success; negative error code, otherwise (errno is also set to
281  * the error code)
282  */
283 LIBBPF_API int bpf_map_update_batch(int fd, const void *keys, const void *values,
284 				    __u32 *count,
285 				    const struct bpf_map_batch_opts *opts);
286 
287 struct bpf_obj_pin_opts {
288 	size_t sz; /* size of this struct for forward/backward compatibility */
289 
290 	__u32 file_flags;
291 	int path_fd;
292 
293 	size_t :0;
294 };
295 #define bpf_obj_pin_opts__last_field path_fd
296 
297 LIBBPF_API int bpf_obj_pin(int fd, const char *pathname);
298 LIBBPF_API int bpf_obj_pin_opts(int fd, const char *pathname,
299 				const struct bpf_obj_pin_opts *opts);
300 
301 struct bpf_obj_get_opts {
302 	size_t sz; /* size of this struct for forward/backward compatibility */
303 
304 	__u32 file_flags;
305 	int path_fd;
306 
307 	size_t :0;
308 };
309 #define bpf_obj_get_opts__last_field path_fd
310 
311 LIBBPF_API int bpf_obj_get(const char *pathname);
312 LIBBPF_API int bpf_obj_get_opts(const char *pathname,
313 				const struct bpf_obj_get_opts *opts);
314 
315 struct bpf_prog_attach_opts {
316 	size_t sz; /* size of this struct for forward/backward compatibility */
317 	unsigned int flags;
318 	int replace_prog_fd;
319 };
320 #define bpf_prog_attach_opts__last_field replace_prog_fd
321 
322 LIBBPF_API int bpf_prog_attach(int prog_fd, int attachable_fd,
323 			       enum bpf_attach_type type, unsigned int flags);
324 LIBBPF_API int bpf_prog_attach_opts(int prog_fd, int attachable_fd,
325 				     enum bpf_attach_type type,
326 				     const struct bpf_prog_attach_opts *opts);
327 LIBBPF_API int bpf_prog_detach(int attachable_fd, enum bpf_attach_type type);
328 LIBBPF_API int bpf_prog_detach2(int prog_fd, int attachable_fd,
329 				enum bpf_attach_type type);
330 
331 union bpf_iter_link_info; /* defined in up-to-date linux/bpf.h */
332 struct bpf_link_create_opts {
333 	size_t sz; /* size of this struct for forward/backward compatibility */
334 	__u32 flags;
335 	union bpf_iter_link_info *iter_info;
336 	__u32 iter_info_len;
337 	__u32 target_btf_id;
338 	union {
339 		struct {
340 			__u64 bpf_cookie;
341 		} perf_event;
342 		struct {
343 			__u32 flags;
344 			__u32 cnt;
345 			const char **syms;
346 			const unsigned long *addrs;
347 			const __u64 *cookies;
348 		} kprobe_multi;
349 		struct {
350 			__u64 cookie;
351 		} tracing;
352 	};
353 	size_t :0;
354 };
355 #define bpf_link_create_opts__last_field kprobe_multi.cookies
356 
357 LIBBPF_API int bpf_link_create(int prog_fd, int target_fd,
358 			       enum bpf_attach_type attach_type,
359 			       const struct bpf_link_create_opts *opts);
360 
361 LIBBPF_API int bpf_link_detach(int link_fd);
362 
363 struct bpf_link_update_opts {
364 	size_t sz; /* size of this struct for forward/backward compatibility */
365 	__u32 flags;	   /* extra flags */
366 	__u32 old_prog_fd; /* expected old program FD */
367 	__u32 old_map_fd;  /* expected old map FD */
368 };
369 #define bpf_link_update_opts__last_field old_map_fd
370 
371 LIBBPF_API int bpf_link_update(int link_fd, int new_prog_fd,
372 			       const struct bpf_link_update_opts *opts);
373 
374 LIBBPF_API int bpf_iter_create(int link_fd);
375 
376 struct bpf_prog_test_run_attr {
377 	int prog_fd;
378 	int repeat;
379 	const void *data_in;
380 	__u32 data_size_in;
381 	void *data_out;      /* optional */
382 	__u32 data_size_out; /* in: max length of data_out
383 			      * out: length of data_out */
384 	__u32 retval;        /* out: return code of the BPF program */
385 	__u32 duration;      /* out: average per repetition in ns */
386 	const void *ctx_in; /* optional */
387 	__u32 ctx_size_in;
388 	void *ctx_out;      /* optional */
389 	__u32 ctx_size_out; /* in: max length of ctx_out
390 			     * out: length of cxt_out */
391 };
392 
393 LIBBPF_API int bpf_prog_get_next_id(__u32 start_id, __u32 *next_id);
394 LIBBPF_API int bpf_map_get_next_id(__u32 start_id, __u32 *next_id);
395 LIBBPF_API int bpf_btf_get_next_id(__u32 start_id, __u32 *next_id);
396 LIBBPF_API int bpf_link_get_next_id(__u32 start_id, __u32 *next_id);
397 
398 struct bpf_get_fd_by_id_opts {
399 	size_t sz; /* size of this struct for forward/backward compatibility */
400 	__u32 open_flags; /* permissions requested for the operation on fd */
401 	size_t :0;
402 };
403 #define bpf_get_fd_by_id_opts__last_field open_flags
404 
405 LIBBPF_API int bpf_prog_get_fd_by_id(__u32 id);
406 LIBBPF_API int bpf_prog_get_fd_by_id_opts(__u32 id,
407 				const struct bpf_get_fd_by_id_opts *opts);
408 LIBBPF_API int bpf_map_get_fd_by_id(__u32 id);
409 LIBBPF_API int bpf_map_get_fd_by_id_opts(__u32 id,
410 				const struct bpf_get_fd_by_id_opts *opts);
411 LIBBPF_API int bpf_btf_get_fd_by_id(__u32 id);
412 LIBBPF_API int bpf_btf_get_fd_by_id_opts(__u32 id,
413 				const struct bpf_get_fd_by_id_opts *opts);
414 LIBBPF_API int bpf_link_get_fd_by_id(__u32 id);
415 LIBBPF_API int bpf_link_get_fd_by_id_opts(__u32 id,
416 				const struct bpf_get_fd_by_id_opts *opts);
417 LIBBPF_API int bpf_obj_get_info_by_fd(int bpf_fd, void *info, __u32 *info_len);
418 
419 /**
420  * @brief **bpf_prog_get_info_by_fd()** obtains information about the BPF
421  * program corresponding to *prog_fd*.
422  *
423  * Populates up to *info_len* bytes of *info* and updates *info_len* with the
424  * actual number of bytes written to *info*.
425  *
426  * @param prog_fd BPF program file descriptor
427  * @param info pointer to **struct bpf_prog_info** that will be populated with
428  * BPF program information
429  * @param info_len pointer to the size of *info*; on success updated with the
430  * number of bytes written to *info*
431  * @return 0, on success; negative error code, otherwise (errno is also set to
432  * the error code)
433  */
434 LIBBPF_API int bpf_prog_get_info_by_fd(int prog_fd, struct bpf_prog_info *info, __u32 *info_len);
435 
436 /**
437  * @brief **bpf_map_get_info_by_fd()** obtains information about the BPF
438  * map corresponding to *map_fd*.
439  *
440  * Populates up to *info_len* bytes of *info* and updates *info_len* with the
441  * actual number of bytes written to *info*.
442  *
443  * @param map_fd BPF map file descriptor
444  * @param info pointer to **struct bpf_map_info** that will be populated with
445  * BPF map information
446  * @param info_len pointer to the size of *info*; on success updated with the
447  * number of bytes written to *info*
448  * @return 0, on success; negative error code, otherwise (errno is also set to
449  * the error code)
450  */
451 LIBBPF_API int bpf_map_get_info_by_fd(int map_fd, struct bpf_map_info *info, __u32 *info_len);
452 
453 /**
454  * @brief **bpf_btf_get_info_by_fd()** obtains information about the
455  * BTF object corresponding to *btf_fd*.
456  *
457  * Populates up to *info_len* bytes of *info* and updates *info_len* with the
458  * actual number of bytes written to *info*.
459  *
460  * @param btf_fd BTF object file descriptor
461  * @param info pointer to **struct bpf_btf_info** that will be populated with
462  * BTF object information
463  * @param info_len pointer to the size of *info*; on success updated with the
464  * number of bytes written to *info*
465  * @return 0, on success; negative error code, otherwise (errno is also set to
466  * the error code)
467  */
468 LIBBPF_API int bpf_btf_get_info_by_fd(int btf_fd, struct bpf_btf_info *info, __u32 *info_len);
469 
470 /**
471  * @brief **bpf_btf_get_info_by_fd()** obtains information about the BPF
472  * link corresponding to *link_fd*.
473  *
474  * Populates up to *info_len* bytes of *info* and updates *info_len* with the
475  * actual number of bytes written to *info*.
476  *
477  * @param link_fd BPF link file descriptor
478  * @param info pointer to **struct bpf_link_info** that will be populated with
479  * BPF link information
480  * @param info_len pointer to the size of *info*; on success updated with the
481  * number of bytes written to *info*
482  * @return 0, on success; negative error code, otherwise (errno is also set to
483  * the error code)
484  */
485 LIBBPF_API int bpf_link_get_info_by_fd(int link_fd, struct bpf_link_info *info, __u32 *info_len);
486 
487 struct bpf_prog_query_opts {
488 	size_t sz; /* size of this struct for forward/backward compatibility */
489 	__u32 query_flags;
490 	__u32 attach_flags; /* output argument */
491 	__u32 *prog_ids;
492 	__u32 prog_cnt; /* input+output argument */
493 	__u32 *prog_attach_flags;
494 };
495 #define bpf_prog_query_opts__last_field prog_attach_flags
496 
497 LIBBPF_API int bpf_prog_query_opts(int target_fd,
498 				   enum bpf_attach_type type,
499 				   struct bpf_prog_query_opts *opts);
500 LIBBPF_API int bpf_prog_query(int target_fd, enum bpf_attach_type type,
501 			      __u32 query_flags, __u32 *attach_flags,
502 			      __u32 *prog_ids, __u32 *prog_cnt);
503 
504 LIBBPF_API int bpf_raw_tracepoint_open(const char *name, int prog_fd);
505 LIBBPF_API int bpf_task_fd_query(int pid, int fd, __u32 flags, char *buf,
506 				 __u32 *buf_len, __u32 *prog_id, __u32 *fd_type,
507 				 __u64 *probe_offset, __u64 *probe_addr);
508 
509 #ifdef __cplusplus
510 /* forward-declaring enums in C++ isn't compatible with pure C enums, so
511  * instead define bpf_enable_stats() as accepting int as an input
512  */
513 LIBBPF_API int bpf_enable_stats(int type);
514 #else
515 enum bpf_stats_type; /* defined in up-to-date linux/bpf.h */
516 LIBBPF_API int bpf_enable_stats(enum bpf_stats_type type);
517 #endif
518 
519 struct bpf_prog_bind_opts {
520 	size_t sz; /* size of this struct for forward/backward compatibility */
521 	__u32 flags;
522 };
523 #define bpf_prog_bind_opts__last_field flags
524 
525 LIBBPF_API int bpf_prog_bind_map(int prog_fd, int map_fd,
526 				 const struct bpf_prog_bind_opts *opts);
527 
528 struct bpf_test_run_opts {
529 	size_t sz; /* size of this struct for forward/backward compatibility */
530 	const void *data_in; /* optional */
531 	void *data_out;      /* optional */
532 	__u32 data_size_in;
533 	__u32 data_size_out; /* in: max length of data_out
534 			      * out: length of data_out
535 			      */
536 	const void *ctx_in; /* optional */
537 	void *ctx_out;      /* optional */
538 	__u32 ctx_size_in;
539 	__u32 ctx_size_out; /* in: max length of ctx_out
540 			     * out: length of cxt_out
541 			     */
542 	__u32 retval;        /* out: return code of the BPF program */
543 	int repeat;
544 	__u32 duration;      /* out: average per repetition in ns */
545 	__u32 flags;
546 	__u32 cpu;
547 	__u32 batch_size;
548 };
549 #define bpf_test_run_opts__last_field batch_size
550 
551 LIBBPF_API int bpf_prog_test_run_opts(int prog_fd,
552 				      struct bpf_test_run_opts *opts);
553 
554 #ifdef __cplusplus
555 } /* extern "C" */
556 #endif
557 
558 #endif /* __LIBBPF_BPF_H */
559