1 // SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
2
3 /*
4 * common eBPF 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
24 #include <stdlib.h>
25 #include <string.h>
26 #include <memory.h>
27 #include <unistd.h>
28 #include <asm/unistd.h>
29 #include <errno.h>
30 #include <linux/bpf.h>
31 #include <linux/filter.h>
32 #include <linux/kernel.h>
33 #include <limits.h>
34 #include <sys/resource.h>
35 #include "bpf.h"
36 #include "libbpf.h"
37 #include "libbpf_internal.h"
38
39 /*
40 * When building perf, unistd.h is overridden. __NR_bpf is
41 * required to be defined explicitly.
42 */
43 #ifndef __NR_bpf
44 # if defined(__i386__)
45 # define __NR_bpf 357
46 # elif defined(__x86_64__)
47 # define __NR_bpf 321
48 # elif defined(__aarch64__)
49 # define __NR_bpf 280
50 # elif defined(__sparc__)
51 # define __NR_bpf 349
52 # elif defined(__s390__)
53 # define __NR_bpf 351
54 # elif defined(__arc__)
55 # define __NR_bpf 280
56 # elif defined(__mips__) && defined(_ABIO32)
57 # define __NR_bpf 4355
58 # elif defined(__mips__) && defined(_ABIN32)
59 # define __NR_bpf 6319
60 # elif defined(__mips__) && defined(_ABI64)
61 # define __NR_bpf 5315
62 # else
63 # error __NR_bpf not defined. libbpf does not support your arch.
64 # endif
65 #endif
66
ptr_to_u64(const void * ptr)67 static inline __u64 ptr_to_u64(const void *ptr)
68 {
69 return (__u64) (unsigned long) ptr;
70 }
71
sys_bpf(enum bpf_cmd cmd,union bpf_attr * attr,unsigned int size)72 static inline int sys_bpf(enum bpf_cmd cmd, union bpf_attr *attr,
73 unsigned int size)
74 {
75 return syscall(__NR_bpf, cmd, attr, size);
76 }
77
sys_bpf_fd(enum bpf_cmd cmd,union bpf_attr * attr,unsigned int size)78 static inline int sys_bpf_fd(enum bpf_cmd cmd, union bpf_attr *attr,
79 unsigned int size)
80 {
81 int fd;
82
83 fd = sys_bpf(cmd, attr, size);
84 return ensure_good_fd(fd);
85 }
86
sys_bpf_prog_load(union bpf_attr * attr,unsigned int size,int attempts)87 int sys_bpf_prog_load(union bpf_attr *attr, unsigned int size, int attempts)
88 {
89 int fd;
90
91 do {
92 fd = sys_bpf_fd(BPF_PROG_LOAD, attr, size);
93 } while (fd < 0 && errno == EAGAIN && --attempts > 0);
94
95 return fd;
96 }
97
98 /* Probe whether kernel switched from memlock-based (RLIMIT_MEMLOCK) to
99 * memcg-based memory accounting for BPF maps and progs. This was done in [0].
100 * We use the support for bpf_ktime_get_coarse_ns() helper, which was added in
101 * the same 5.11 Linux release ([1]), to detect memcg-based accounting for BPF.
102 *
103 * [0] https://lore.kernel.org/bpf/20201201215900.3569844-1-guro@fb.com/
104 * [1] d05512618056 ("bpf: Add bpf_ktime_get_coarse_ns helper")
105 */
probe_memcg_account(void)106 int probe_memcg_account(void)
107 {
108 const size_t attr_sz = offsetofend(union bpf_attr, attach_btf_obj_fd);
109 struct bpf_insn insns[] = {
110 BPF_EMIT_CALL(BPF_FUNC_ktime_get_coarse_ns),
111 BPF_EXIT_INSN(),
112 };
113 size_t insn_cnt = ARRAY_SIZE(insns);
114 union bpf_attr attr;
115 int prog_fd;
116
117 /* attempt loading freplace trying to use custom BTF */
118 memset(&attr, 0, attr_sz);
119 attr.prog_type = BPF_PROG_TYPE_SOCKET_FILTER;
120 attr.insns = ptr_to_u64(insns);
121 attr.insn_cnt = insn_cnt;
122 attr.license = ptr_to_u64("GPL");
123
124 prog_fd = sys_bpf_fd(BPF_PROG_LOAD, &attr, attr_sz);
125 if (prog_fd >= 0) {
126 close(prog_fd);
127 return 1;
128 }
129 return 0;
130 }
131
132 static bool memlock_bumped;
133 static rlim_t memlock_rlim = RLIM_INFINITY;
134
libbpf_set_memlock_rlim(size_t memlock_bytes)135 int libbpf_set_memlock_rlim(size_t memlock_bytes)
136 {
137 if (memlock_bumped)
138 return libbpf_err(-EBUSY);
139
140 memlock_rlim = memlock_bytes;
141 return 0;
142 }
143
bump_rlimit_memlock(void)144 int bump_rlimit_memlock(void)
145 {
146 struct rlimit rlim;
147
148 /* if kernel supports memcg-based accounting, skip bumping RLIMIT_MEMLOCK */
149 if (memlock_bumped || kernel_supports(NULL, FEAT_MEMCG_ACCOUNT))
150 return 0;
151
152 memlock_bumped = true;
153
154 /* zero memlock_rlim_max disables auto-bumping RLIMIT_MEMLOCK */
155 if (memlock_rlim == 0)
156 return 0;
157
158 rlim.rlim_cur = rlim.rlim_max = memlock_rlim;
159 if (setrlimit(RLIMIT_MEMLOCK, &rlim))
160 return -errno;
161
162 return 0;
163 }
164
bpf_map_create(enum bpf_map_type map_type,const char * map_name,__u32 key_size,__u32 value_size,__u32 max_entries,const struct bpf_map_create_opts * opts)165 int bpf_map_create(enum bpf_map_type map_type,
166 const char *map_name,
167 __u32 key_size,
168 __u32 value_size,
169 __u32 max_entries,
170 const struct bpf_map_create_opts *opts)
171 {
172 const size_t attr_sz = offsetofend(union bpf_attr, map_extra);
173 union bpf_attr attr;
174 int fd;
175
176 bump_rlimit_memlock();
177
178 memset(&attr, 0, attr_sz);
179
180 if (!OPTS_VALID(opts, bpf_map_create_opts))
181 return libbpf_err(-EINVAL);
182
183 attr.map_type = map_type;
184 if (map_name && kernel_supports(NULL, FEAT_PROG_NAME))
185 libbpf_strlcpy(attr.map_name, map_name, sizeof(attr.map_name));
186 attr.key_size = key_size;
187 attr.value_size = value_size;
188 attr.max_entries = max_entries;
189
190 attr.btf_fd = OPTS_GET(opts, btf_fd, 0);
191 attr.btf_key_type_id = OPTS_GET(opts, btf_key_type_id, 0);
192 attr.btf_value_type_id = OPTS_GET(opts, btf_value_type_id, 0);
193 attr.btf_vmlinux_value_type_id = OPTS_GET(opts, btf_vmlinux_value_type_id, 0);
194
195 attr.inner_map_fd = OPTS_GET(opts, inner_map_fd, 0);
196 attr.map_flags = OPTS_GET(opts, map_flags, 0);
197 attr.map_extra = OPTS_GET(opts, map_extra, 0);
198 attr.numa_node = OPTS_GET(opts, numa_node, 0);
199 attr.map_ifindex = OPTS_GET(opts, map_ifindex, 0);
200
201 fd = sys_bpf_fd(BPF_MAP_CREATE, &attr, attr_sz);
202 return libbpf_err_errno(fd);
203 }
204
205 static void *
alloc_zero_tailing_info(const void * orecord,__u32 cnt,__u32 actual_rec_size,__u32 expected_rec_size)206 alloc_zero_tailing_info(const void *orecord, __u32 cnt,
207 __u32 actual_rec_size, __u32 expected_rec_size)
208 {
209 __u64 info_len = (__u64)actual_rec_size * cnt;
210 void *info, *nrecord;
211 int i;
212
213 info = malloc(info_len);
214 if (!info)
215 return NULL;
216
217 /* zero out bytes kernel does not understand */
218 nrecord = info;
219 for (i = 0; i < cnt; i++) {
220 memcpy(nrecord, orecord, expected_rec_size);
221 memset(nrecord + expected_rec_size, 0,
222 actual_rec_size - expected_rec_size);
223 orecord += actual_rec_size;
224 nrecord += actual_rec_size;
225 }
226
227 return info;
228 }
229
bpf_prog_load(enum bpf_prog_type prog_type,const char * prog_name,const char * license,const struct bpf_insn * insns,size_t insn_cnt,struct bpf_prog_load_opts * opts)230 int bpf_prog_load(enum bpf_prog_type prog_type,
231 const char *prog_name, const char *license,
232 const struct bpf_insn *insns, size_t insn_cnt,
233 struct bpf_prog_load_opts *opts)
234 {
235 const size_t attr_sz = offsetofend(union bpf_attr, log_true_size);
236 void *finfo = NULL, *linfo = NULL;
237 const char *func_info, *line_info;
238 __u32 log_size, log_level, attach_prog_fd, attach_btf_obj_fd;
239 __u32 func_info_rec_size, line_info_rec_size;
240 int fd, attempts;
241 union bpf_attr attr;
242 char *log_buf;
243
244 bump_rlimit_memlock();
245
246 if (!OPTS_VALID(opts, bpf_prog_load_opts))
247 return libbpf_err(-EINVAL);
248
249 attempts = OPTS_GET(opts, attempts, 0);
250 if (attempts < 0)
251 return libbpf_err(-EINVAL);
252 if (attempts == 0)
253 attempts = PROG_LOAD_ATTEMPTS;
254
255 memset(&attr, 0, attr_sz);
256
257 attr.prog_type = prog_type;
258 attr.expected_attach_type = OPTS_GET(opts, expected_attach_type, 0);
259
260 attr.prog_btf_fd = OPTS_GET(opts, prog_btf_fd, 0);
261 attr.prog_flags = OPTS_GET(opts, prog_flags, 0);
262 attr.prog_ifindex = OPTS_GET(opts, prog_ifindex, 0);
263 attr.kern_version = OPTS_GET(opts, kern_version, 0);
264
265 if (prog_name && kernel_supports(NULL, FEAT_PROG_NAME))
266 libbpf_strlcpy(attr.prog_name, prog_name, sizeof(attr.prog_name));
267 attr.license = ptr_to_u64(license);
268
269 if (insn_cnt > UINT_MAX)
270 return libbpf_err(-E2BIG);
271
272 attr.insns = ptr_to_u64(insns);
273 attr.insn_cnt = (__u32)insn_cnt;
274
275 attach_prog_fd = OPTS_GET(opts, attach_prog_fd, 0);
276 attach_btf_obj_fd = OPTS_GET(opts, attach_btf_obj_fd, 0);
277
278 if (attach_prog_fd && attach_btf_obj_fd)
279 return libbpf_err(-EINVAL);
280
281 attr.attach_btf_id = OPTS_GET(opts, attach_btf_id, 0);
282 if (attach_prog_fd)
283 attr.attach_prog_fd = attach_prog_fd;
284 else
285 attr.attach_btf_obj_fd = attach_btf_obj_fd;
286
287 log_buf = OPTS_GET(opts, log_buf, NULL);
288 log_size = OPTS_GET(opts, log_size, 0);
289 log_level = OPTS_GET(opts, log_level, 0);
290
291 if (!!log_buf != !!log_size)
292 return libbpf_err(-EINVAL);
293
294 func_info_rec_size = OPTS_GET(opts, func_info_rec_size, 0);
295 func_info = OPTS_GET(opts, func_info, NULL);
296 attr.func_info_rec_size = func_info_rec_size;
297 attr.func_info = ptr_to_u64(func_info);
298 attr.func_info_cnt = OPTS_GET(opts, func_info_cnt, 0);
299
300 line_info_rec_size = OPTS_GET(opts, line_info_rec_size, 0);
301 line_info = OPTS_GET(opts, line_info, NULL);
302 attr.line_info_rec_size = line_info_rec_size;
303 attr.line_info = ptr_to_u64(line_info);
304 attr.line_info_cnt = OPTS_GET(opts, line_info_cnt, 0);
305
306 attr.fd_array = ptr_to_u64(OPTS_GET(opts, fd_array, NULL));
307
308 if (log_level) {
309 attr.log_buf = ptr_to_u64(log_buf);
310 attr.log_size = log_size;
311 attr.log_level = log_level;
312 }
313
314 fd = sys_bpf_prog_load(&attr, attr_sz, attempts);
315 OPTS_SET(opts, log_true_size, attr.log_true_size);
316 if (fd >= 0)
317 return fd;
318
319 /* After bpf_prog_load, the kernel may modify certain attributes
320 * to give user space a hint how to deal with loading failure.
321 * Check to see whether we can make some changes and load again.
322 */
323 while (errno == E2BIG && (!finfo || !linfo)) {
324 if (!finfo && attr.func_info_cnt &&
325 attr.func_info_rec_size < func_info_rec_size) {
326 /* try with corrected func info records */
327 finfo = alloc_zero_tailing_info(func_info,
328 attr.func_info_cnt,
329 func_info_rec_size,
330 attr.func_info_rec_size);
331 if (!finfo) {
332 errno = E2BIG;
333 goto done;
334 }
335
336 attr.func_info = ptr_to_u64(finfo);
337 attr.func_info_rec_size = func_info_rec_size;
338 } else if (!linfo && attr.line_info_cnt &&
339 attr.line_info_rec_size < line_info_rec_size) {
340 linfo = alloc_zero_tailing_info(line_info,
341 attr.line_info_cnt,
342 line_info_rec_size,
343 attr.line_info_rec_size);
344 if (!linfo) {
345 errno = E2BIG;
346 goto done;
347 }
348
349 attr.line_info = ptr_to_u64(linfo);
350 attr.line_info_rec_size = line_info_rec_size;
351 } else {
352 break;
353 }
354
355 fd = sys_bpf_prog_load(&attr, attr_sz, attempts);
356 OPTS_SET(opts, log_true_size, attr.log_true_size);
357 if (fd >= 0)
358 goto done;
359 }
360
361 if (log_level == 0 && log_buf) {
362 /* log_level == 0 with non-NULL log_buf requires retrying on error
363 * with log_level == 1 and log_buf/log_buf_size set, to get details of
364 * failure
365 */
366 attr.log_buf = ptr_to_u64(log_buf);
367 attr.log_size = log_size;
368 attr.log_level = 1;
369
370 fd = sys_bpf_prog_load(&attr, attr_sz, attempts);
371 OPTS_SET(opts, log_true_size, attr.log_true_size);
372 }
373 done:
374 /* free() doesn't affect errno, so we don't need to restore it */
375 free(finfo);
376 free(linfo);
377 return libbpf_err_errno(fd);
378 }
379
bpf_map_update_elem(int fd,const void * key,const void * value,__u64 flags)380 int bpf_map_update_elem(int fd, const void *key, const void *value,
381 __u64 flags)
382 {
383 const size_t attr_sz = offsetofend(union bpf_attr, flags);
384 union bpf_attr attr;
385 int ret;
386
387 memset(&attr, 0, attr_sz);
388 attr.map_fd = fd;
389 attr.key = ptr_to_u64(key);
390 attr.value = ptr_to_u64(value);
391 attr.flags = flags;
392
393 ret = sys_bpf(BPF_MAP_UPDATE_ELEM, &attr, attr_sz);
394 return libbpf_err_errno(ret);
395 }
396
bpf_map_lookup_elem(int fd,const void * key,void * value)397 int bpf_map_lookup_elem(int fd, const void *key, void *value)
398 {
399 const size_t attr_sz = offsetofend(union bpf_attr, flags);
400 union bpf_attr attr;
401 int ret;
402
403 memset(&attr, 0, attr_sz);
404 attr.map_fd = fd;
405 attr.key = ptr_to_u64(key);
406 attr.value = ptr_to_u64(value);
407
408 ret = sys_bpf(BPF_MAP_LOOKUP_ELEM, &attr, attr_sz);
409 return libbpf_err_errno(ret);
410 }
411
bpf_map_lookup_elem_flags(int fd,const void * key,void * value,__u64 flags)412 int bpf_map_lookup_elem_flags(int fd, const void *key, void *value, __u64 flags)
413 {
414 const size_t attr_sz = offsetofend(union bpf_attr, flags);
415 union bpf_attr attr;
416 int ret;
417
418 memset(&attr, 0, attr_sz);
419 attr.map_fd = fd;
420 attr.key = ptr_to_u64(key);
421 attr.value = ptr_to_u64(value);
422 attr.flags = flags;
423
424 ret = sys_bpf(BPF_MAP_LOOKUP_ELEM, &attr, attr_sz);
425 return libbpf_err_errno(ret);
426 }
427
bpf_map_lookup_and_delete_elem(int fd,const void * key,void * value)428 int bpf_map_lookup_and_delete_elem(int fd, const void *key, void *value)
429 {
430 const size_t attr_sz = offsetofend(union bpf_attr, flags);
431 union bpf_attr attr;
432 int ret;
433
434 memset(&attr, 0, attr_sz);
435 attr.map_fd = fd;
436 attr.key = ptr_to_u64(key);
437 attr.value = ptr_to_u64(value);
438
439 ret = sys_bpf(BPF_MAP_LOOKUP_AND_DELETE_ELEM, &attr, attr_sz);
440 return libbpf_err_errno(ret);
441 }
442
bpf_map_lookup_and_delete_elem_flags(int fd,const void * key,void * value,__u64 flags)443 int bpf_map_lookup_and_delete_elem_flags(int fd, const void *key, void *value, __u64 flags)
444 {
445 const size_t attr_sz = offsetofend(union bpf_attr, flags);
446 union bpf_attr attr;
447 int ret;
448
449 memset(&attr, 0, attr_sz);
450 attr.map_fd = fd;
451 attr.key = ptr_to_u64(key);
452 attr.value = ptr_to_u64(value);
453 attr.flags = flags;
454
455 ret = sys_bpf(BPF_MAP_LOOKUP_AND_DELETE_ELEM, &attr, attr_sz);
456 return libbpf_err_errno(ret);
457 }
458
bpf_map_delete_elem(int fd,const void * key)459 int bpf_map_delete_elem(int fd, const void *key)
460 {
461 const size_t attr_sz = offsetofend(union bpf_attr, flags);
462 union bpf_attr attr;
463 int ret;
464
465 memset(&attr, 0, attr_sz);
466 attr.map_fd = fd;
467 attr.key = ptr_to_u64(key);
468
469 ret = sys_bpf(BPF_MAP_DELETE_ELEM, &attr, attr_sz);
470 return libbpf_err_errno(ret);
471 }
472
bpf_map_delete_elem_flags(int fd,const void * key,__u64 flags)473 int bpf_map_delete_elem_flags(int fd, const void *key, __u64 flags)
474 {
475 const size_t attr_sz = offsetofend(union bpf_attr, flags);
476 union bpf_attr attr;
477 int ret;
478
479 memset(&attr, 0, attr_sz);
480 attr.map_fd = fd;
481 attr.key = ptr_to_u64(key);
482 attr.flags = flags;
483
484 ret = sys_bpf(BPF_MAP_DELETE_ELEM, &attr, attr_sz);
485 return libbpf_err_errno(ret);
486 }
487
bpf_map_get_next_key(int fd,const void * key,void * next_key)488 int bpf_map_get_next_key(int fd, const void *key, void *next_key)
489 {
490 const size_t attr_sz = offsetofend(union bpf_attr, next_key);
491 union bpf_attr attr;
492 int ret;
493
494 memset(&attr, 0, attr_sz);
495 attr.map_fd = fd;
496 attr.key = ptr_to_u64(key);
497 attr.next_key = ptr_to_u64(next_key);
498
499 ret = sys_bpf(BPF_MAP_GET_NEXT_KEY, &attr, attr_sz);
500 return libbpf_err_errno(ret);
501 }
502
bpf_map_freeze(int fd)503 int bpf_map_freeze(int fd)
504 {
505 const size_t attr_sz = offsetofend(union bpf_attr, map_fd);
506 union bpf_attr attr;
507 int ret;
508
509 memset(&attr, 0, attr_sz);
510 attr.map_fd = fd;
511
512 ret = sys_bpf(BPF_MAP_FREEZE, &attr, attr_sz);
513 return libbpf_err_errno(ret);
514 }
515
bpf_map_batch_common(int cmd,int fd,void * in_batch,void * out_batch,void * keys,void * values,__u32 * count,const struct bpf_map_batch_opts * opts)516 static int bpf_map_batch_common(int cmd, int fd, void *in_batch,
517 void *out_batch, void *keys, void *values,
518 __u32 *count,
519 const struct bpf_map_batch_opts *opts)
520 {
521 const size_t attr_sz = offsetofend(union bpf_attr, batch);
522 union bpf_attr attr;
523 int ret;
524
525 if (!OPTS_VALID(opts, bpf_map_batch_opts))
526 return libbpf_err(-EINVAL);
527
528 memset(&attr, 0, attr_sz);
529 attr.batch.map_fd = fd;
530 attr.batch.in_batch = ptr_to_u64(in_batch);
531 attr.batch.out_batch = ptr_to_u64(out_batch);
532 attr.batch.keys = ptr_to_u64(keys);
533 attr.batch.values = ptr_to_u64(values);
534 attr.batch.count = *count;
535 attr.batch.elem_flags = OPTS_GET(opts, elem_flags, 0);
536 attr.batch.flags = OPTS_GET(opts, flags, 0);
537
538 ret = sys_bpf(cmd, &attr, attr_sz);
539 *count = attr.batch.count;
540
541 return libbpf_err_errno(ret);
542 }
543
bpf_map_delete_batch(int fd,const void * keys,__u32 * count,const struct bpf_map_batch_opts * opts)544 int bpf_map_delete_batch(int fd, const void *keys, __u32 *count,
545 const struct bpf_map_batch_opts *opts)
546 {
547 return bpf_map_batch_common(BPF_MAP_DELETE_BATCH, fd, NULL,
548 NULL, (void *)keys, NULL, count, opts);
549 }
550
bpf_map_lookup_batch(int fd,void * in_batch,void * out_batch,void * keys,void * values,__u32 * count,const struct bpf_map_batch_opts * opts)551 int bpf_map_lookup_batch(int fd, void *in_batch, void *out_batch, void *keys,
552 void *values, __u32 *count,
553 const struct bpf_map_batch_opts *opts)
554 {
555 return bpf_map_batch_common(BPF_MAP_LOOKUP_BATCH, fd, in_batch,
556 out_batch, keys, values, count, opts);
557 }
558
bpf_map_lookup_and_delete_batch(int fd,void * in_batch,void * out_batch,void * keys,void * values,__u32 * count,const struct bpf_map_batch_opts * opts)559 int bpf_map_lookup_and_delete_batch(int fd, void *in_batch, void *out_batch,
560 void *keys, void *values, __u32 *count,
561 const struct bpf_map_batch_opts *opts)
562 {
563 return bpf_map_batch_common(BPF_MAP_LOOKUP_AND_DELETE_BATCH,
564 fd, in_batch, out_batch, keys, values,
565 count, opts);
566 }
567
bpf_map_update_batch(int fd,const void * keys,const void * values,__u32 * count,const struct bpf_map_batch_opts * opts)568 int bpf_map_update_batch(int fd, const void *keys, const void *values, __u32 *count,
569 const struct bpf_map_batch_opts *opts)
570 {
571 return bpf_map_batch_common(BPF_MAP_UPDATE_BATCH, fd, NULL, NULL,
572 (void *)keys, (void *)values, count, opts);
573 }
574
bpf_obj_pin_opts(int fd,const char * pathname,const struct bpf_obj_pin_opts * opts)575 int bpf_obj_pin_opts(int fd, const char *pathname, const struct bpf_obj_pin_opts *opts)
576 {
577 const size_t attr_sz = offsetofend(union bpf_attr, path_fd);
578 union bpf_attr attr;
579 int ret;
580
581 if (!OPTS_VALID(opts, bpf_obj_pin_opts))
582 return libbpf_err(-EINVAL);
583
584 memset(&attr, 0, attr_sz);
585 attr.path_fd = OPTS_GET(opts, path_fd, 0);
586 attr.pathname = ptr_to_u64((void *)pathname);
587 attr.file_flags = OPTS_GET(opts, file_flags, 0);
588 attr.bpf_fd = fd;
589
590 ret = sys_bpf(BPF_OBJ_PIN, &attr, attr_sz);
591 return libbpf_err_errno(ret);
592 }
593
bpf_obj_pin(int fd,const char * pathname)594 int bpf_obj_pin(int fd, const char *pathname)
595 {
596 return bpf_obj_pin_opts(fd, pathname, NULL);
597 }
598
bpf_obj_get(const char * pathname)599 int bpf_obj_get(const char *pathname)
600 {
601 return bpf_obj_get_opts(pathname, NULL);
602 }
603
bpf_obj_get_opts(const char * pathname,const struct bpf_obj_get_opts * opts)604 int bpf_obj_get_opts(const char *pathname, const struct bpf_obj_get_opts *opts)
605 {
606 const size_t attr_sz = offsetofend(union bpf_attr, path_fd);
607 union bpf_attr attr;
608 int fd;
609
610 if (!OPTS_VALID(opts, bpf_obj_get_opts))
611 return libbpf_err(-EINVAL);
612
613 memset(&attr, 0, attr_sz);
614 attr.path_fd = OPTS_GET(opts, path_fd, 0);
615 attr.pathname = ptr_to_u64((void *)pathname);
616 attr.file_flags = OPTS_GET(opts, file_flags, 0);
617
618 fd = sys_bpf_fd(BPF_OBJ_GET, &attr, attr_sz);
619 return libbpf_err_errno(fd);
620 }
621
bpf_prog_attach(int prog_fd,int target_fd,enum bpf_attach_type type,unsigned int flags)622 int bpf_prog_attach(int prog_fd, int target_fd, enum bpf_attach_type type,
623 unsigned int flags)
624 {
625 DECLARE_LIBBPF_OPTS(bpf_prog_attach_opts, opts,
626 .flags = flags,
627 );
628
629 return bpf_prog_attach_opts(prog_fd, target_fd, type, &opts);
630 }
631
bpf_prog_attach_opts(int prog_fd,int target,enum bpf_attach_type type,const struct bpf_prog_attach_opts * opts)632 int bpf_prog_attach_opts(int prog_fd, int target, enum bpf_attach_type type,
633 const struct bpf_prog_attach_opts *opts)
634 {
635 const size_t attr_sz = offsetofend(union bpf_attr, expected_revision);
636 __u32 relative_id, flags;
637 int ret, relative_fd;
638 union bpf_attr attr;
639
640 if (!OPTS_VALID(opts, bpf_prog_attach_opts))
641 return libbpf_err(-EINVAL);
642
643 relative_id = OPTS_GET(opts, relative_id, 0);
644 relative_fd = OPTS_GET(opts, relative_fd, 0);
645 flags = OPTS_GET(opts, flags, 0);
646
647 /* validate we don't have unexpected combinations of non-zero fields */
648 if (relative_fd && relative_id)
649 return libbpf_err(-EINVAL);
650
651 memset(&attr, 0, attr_sz);
652 attr.target_fd = target;
653 attr.attach_bpf_fd = prog_fd;
654 attr.attach_type = type;
655 attr.replace_bpf_fd = OPTS_GET(opts, replace_fd, 0);
656 attr.expected_revision = OPTS_GET(opts, expected_revision, 0);
657
658 if (relative_id) {
659 attr.attach_flags = flags | BPF_F_ID;
660 attr.relative_id = relative_id;
661 } else {
662 attr.attach_flags = flags;
663 attr.relative_fd = relative_fd;
664 }
665
666 ret = sys_bpf(BPF_PROG_ATTACH, &attr, attr_sz);
667 return libbpf_err_errno(ret);
668 }
669
bpf_prog_detach_opts(int prog_fd,int target,enum bpf_attach_type type,const struct bpf_prog_detach_opts * opts)670 int bpf_prog_detach_opts(int prog_fd, int target, enum bpf_attach_type type,
671 const struct bpf_prog_detach_opts *opts)
672 {
673 const size_t attr_sz = offsetofend(union bpf_attr, expected_revision);
674 __u32 relative_id, flags;
675 int ret, relative_fd;
676 union bpf_attr attr;
677
678 if (!OPTS_VALID(opts, bpf_prog_detach_opts))
679 return libbpf_err(-EINVAL);
680
681 relative_id = OPTS_GET(opts, relative_id, 0);
682 relative_fd = OPTS_GET(opts, relative_fd, 0);
683 flags = OPTS_GET(opts, flags, 0);
684
685 /* validate we don't have unexpected combinations of non-zero fields */
686 if (relative_fd && relative_id)
687 return libbpf_err(-EINVAL);
688
689 memset(&attr, 0, attr_sz);
690 attr.target_fd = target;
691 attr.attach_bpf_fd = prog_fd;
692 attr.attach_type = type;
693 attr.expected_revision = OPTS_GET(opts, expected_revision, 0);
694
695 if (relative_id) {
696 attr.attach_flags = flags | BPF_F_ID;
697 attr.relative_id = relative_id;
698 } else {
699 attr.attach_flags = flags;
700 attr.relative_fd = relative_fd;
701 }
702
703 ret = sys_bpf(BPF_PROG_DETACH, &attr, attr_sz);
704 return libbpf_err_errno(ret);
705 }
706
bpf_prog_detach(int target_fd,enum bpf_attach_type type)707 int bpf_prog_detach(int target_fd, enum bpf_attach_type type)
708 {
709 return bpf_prog_detach_opts(0, target_fd, type, NULL);
710 }
711
bpf_prog_detach2(int prog_fd,int target_fd,enum bpf_attach_type type)712 int bpf_prog_detach2(int prog_fd, int target_fd, enum bpf_attach_type type)
713 {
714 return bpf_prog_detach_opts(prog_fd, target_fd, type, NULL);
715 }
716
bpf_link_create(int prog_fd,int target_fd,enum bpf_attach_type attach_type,const struct bpf_link_create_opts * opts)717 int bpf_link_create(int prog_fd, int target_fd,
718 enum bpf_attach_type attach_type,
719 const struct bpf_link_create_opts *opts)
720 {
721 const size_t attr_sz = offsetofend(union bpf_attr, link_create);
722 __u32 target_btf_id, iter_info_len, relative_id;
723 int fd, err, relative_fd;
724 union bpf_attr attr;
725
726 if (!OPTS_VALID(opts, bpf_link_create_opts))
727 return libbpf_err(-EINVAL);
728
729 iter_info_len = OPTS_GET(opts, iter_info_len, 0);
730 target_btf_id = OPTS_GET(opts, target_btf_id, 0);
731
732 /* validate we don't have unexpected combinations of non-zero fields */
733 if (iter_info_len || target_btf_id) {
734 if (iter_info_len && target_btf_id)
735 return libbpf_err(-EINVAL);
736 if (!OPTS_ZEROED(opts, target_btf_id))
737 return libbpf_err(-EINVAL);
738 }
739
740 memset(&attr, 0, attr_sz);
741 attr.link_create.prog_fd = prog_fd;
742 attr.link_create.target_fd = target_fd;
743 attr.link_create.attach_type = attach_type;
744 attr.link_create.flags = OPTS_GET(opts, flags, 0);
745
746 if (target_btf_id) {
747 attr.link_create.target_btf_id = target_btf_id;
748 goto proceed;
749 }
750
751 switch (attach_type) {
752 case BPF_TRACE_ITER:
753 attr.link_create.iter_info = ptr_to_u64(OPTS_GET(opts, iter_info, (void *)0));
754 attr.link_create.iter_info_len = iter_info_len;
755 break;
756 case BPF_PERF_EVENT:
757 attr.link_create.perf_event.bpf_cookie = OPTS_GET(opts, perf_event.bpf_cookie, 0);
758 if (!OPTS_ZEROED(opts, perf_event))
759 return libbpf_err(-EINVAL);
760 break;
761 case BPF_TRACE_KPROBE_MULTI:
762 attr.link_create.kprobe_multi.flags = OPTS_GET(opts, kprobe_multi.flags, 0);
763 attr.link_create.kprobe_multi.cnt = OPTS_GET(opts, kprobe_multi.cnt, 0);
764 attr.link_create.kprobe_multi.syms = ptr_to_u64(OPTS_GET(opts, kprobe_multi.syms, 0));
765 attr.link_create.kprobe_multi.addrs = ptr_to_u64(OPTS_GET(opts, kprobe_multi.addrs, 0));
766 attr.link_create.kprobe_multi.cookies = ptr_to_u64(OPTS_GET(opts, kprobe_multi.cookies, 0));
767 if (!OPTS_ZEROED(opts, kprobe_multi))
768 return libbpf_err(-EINVAL);
769 break;
770 case BPF_TRACE_UPROBE_MULTI:
771 attr.link_create.uprobe_multi.flags = OPTS_GET(opts, uprobe_multi.flags, 0);
772 attr.link_create.uprobe_multi.cnt = OPTS_GET(opts, uprobe_multi.cnt, 0);
773 attr.link_create.uprobe_multi.path = ptr_to_u64(OPTS_GET(opts, uprobe_multi.path, 0));
774 attr.link_create.uprobe_multi.offsets = ptr_to_u64(OPTS_GET(opts, uprobe_multi.offsets, 0));
775 attr.link_create.uprobe_multi.ref_ctr_offsets = ptr_to_u64(OPTS_GET(opts, uprobe_multi.ref_ctr_offsets, 0));
776 attr.link_create.uprobe_multi.cookies = ptr_to_u64(OPTS_GET(opts, uprobe_multi.cookies, 0));
777 attr.link_create.uprobe_multi.pid = OPTS_GET(opts, uprobe_multi.pid, 0);
778 if (!OPTS_ZEROED(opts, uprobe_multi))
779 return libbpf_err(-EINVAL);
780 break;
781 case BPF_TRACE_FENTRY:
782 case BPF_TRACE_FEXIT:
783 case BPF_MODIFY_RETURN:
784 case BPF_LSM_MAC:
785 attr.link_create.tracing.cookie = OPTS_GET(opts, tracing.cookie, 0);
786 if (!OPTS_ZEROED(opts, tracing))
787 return libbpf_err(-EINVAL);
788 break;
789 case BPF_NETFILTER:
790 attr.link_create.netfilter.pf = OPTS_GET(opts, netfilter.pf, 0);
791 attr.link_create.netfilter.hooknum = OPTS_GET(opts, netfilter.hooknum, 0);
792 attr.link_create.netfilter.priority = OPTS_GET(opts, netfilter.priority, 0);
793 attr.link_create.netfilter.flags = OPTS_GET(opts, netfilter.flags, 0);
794 if (!OPTS_ZEROED(opts, netfilter))
795 return libbpf_err(-EINVAL);
796 break;
797 case BPF_TCX_INGRESS:
798 case BPF_TCX_EGRESS:
799 relative_fd = OPTS_GET(opts, tcx.relative_fd, 0);
800 relative_id = OPTS_GET(opts, tcx.relative_id, 0);
801 if (relative_fd && relative_id)
802 return libbpf_err(-EINVAL);
803 if (relative_id) {
804 attr.link_create.tcx.relative_id = relative_id;
805 attr.link_create.flags |= BPF_F_ID;
806 } else {
807 attr.link_create.tcx.relative_fd = relative_fd;
808 }
809 attr.link_create.tcx.expected_revision = OPTS_GET(opts, tcx.expected_revision, 0);
810 if (!OPTS_ZEROED(opts, tcx))
811 return libbpf_err(-EINVAL);
812 break;
813 default:
814 if (!OPTS_ZEROED(opts, flags))
815 return libbpf_err(-EINVAL);
816 break;
817 }
818 proceed:
819 fd = sys_bpf_fd(BPF_LINK_CREATE, &attr, attr_sz);
820 if (fd >= 0)
821 return fd;
822 /* we'll get EINVAL if LINK_CREATE doesn't support attaching fentry
823 * and other similar programs
824 */
825 err = -errno;
826 if (err != -EINVAL)
827 return libbpf_err(err);
828
829 /* if user used features not supported by
830 * BPF_RAW_TRACEPOINT_OPEN command, then just give up immediately
831 */
832 if (attr.link_create.target_fd || attr.link_create.target_btf_id)
833 return libbpf_err(err);
834 if (!OPTS_ZEROED(opts, sz))
835 return libbpf_err(err);
836
837 /* otherwise, for few select kinds of programs that can be
838 * attached using BPF_RAW_TRACEPOINT_OPEN command, try that as
839 * a fallback for older kernels
840 */
841 switch (attach_type) {
842 case BPF_TRACE_RAW_TP:
843 case BPF_LSM_MAC:
844 case BPF_TRACE_FENTRY:
845 case BPF_TRACE_FEXIT:
846 case BPF_MODIFY_RETURN:
847 return bpf_raw_tracepoint_open(NULL, prog_fd);
848 default:
849 return libbpf_err(err);
850 }
851 }
852
bpf_link_detach(int link_fd)853 int bpf_link_detach(int link_fd)
854 {
855 const size_t attr_sz = offsetofend(union bpf_attr, link_detach);
856 union bpf_attr attr;
857 int ret;
858
859 memset(&attr, 0, attr_sz);
860 attr.link_detach.link_fd = link_fd;
861
862 ret = sys_bpf(BPF_LINK_DETACH, &attr, attr_sz);
863 return libbpf_err_errno(ret);
864 }
865
bpf_link_update(int link_fd,int new_prog_fd,const struct bpf_link_update_opts * opts)866 int bpf_link_update(int link_fd, int new_prog_fd,
867 const struct bpf_link_update_opts *opts)
868 {
869 const size_t attr_sz = offsetofend(union bpf_attr, link_update);
870 union bpf_attr attr;
871 int ret;
872
873 if (!OPTS_VALID(opts, bpf_link_update_opts))
874 return libbpf_err(-EINVAL);
875
876 if (OPTS_GET(opts, old_prog_fd, 0) && OPTS_GET(opts, old_map_fd, 0))
877 return libbpf_err(-EINVAL);
878
879 memset(&attr, 0, attr_sz);
880 attr.link_update.link_fd = link_fd;
881 attr.link_update.new_prog_fd = new_prog_fd;
882 attr.link_update.flags = OPTS_GET(opts, flags, 0);
883 if (OPTS_GET(opts, old_prog_fd, 0))
884 attr.link_update.old_prog_fd = OPTS_GET(opts, old_prog_fd, 0);
885 else if (OPTS_GET(opts, old_map_fd, 0))
886 attr.link_update.old_map_fd = OPTS_GET(opts, old_map_fd, 0);
887
888 ret = sys_bpf(BPF_LINK_UPDATE, &attr, attr_sz);
889 return libbpf_err_errno(ret);
890 }
891
bpf_iter_create(int link_fd)892 int bpf_iter_create(int link_fd)
893 {
894 const size_t attr_sz = offsetofend(union bpf_attr, iter_create);
895 union bpf_attr attr;
896 int fd;
897
898 memset(&attr, 0, attr_sz);
899 attr.iter_create.link_fd = link_fd;
900
901 fd = sys_bpf_fd(BPF_ITER_CREATE, &attr, attr_sz);
902 return libbpf_err_errno(fd);
903 }
904
bpf_prog_query_opts(int target,enum bpf_attach_type type,struct bpf_prog_query_opts * opts)905 int bpf_prog_query_opts(int target, enum bpf_attach_type type,
906 struct bpf_prog_query_opts *opts)
907 {
908 const size_t attr_sz = offsetofend(union bpf_attr, query);
909 union bpf_attr attr;
910 int ret;
911
912 if (!OPTS_VALID(opts, bpf_prog_query_opts))
913 return libbpf_err(-EINVAL);
914
915 memset(&attr, 0, attr_sz);
916 attr.query.target_fd = target;
917 attr.query.attach_type = type;
918 attr.query.query_flags = OPTS_GET(opts, query_flags, 0);
919 attr.query.count = OPTS_GET(opts, count, 0);
920 attr.query.prog_ids = ptr_to_u64(OPTS_GET(opts, prog_ids, NULL));
921 attr.query.link_ids = ptr_to_u64(OPTS_GET(opts, link_ids, NULL));
922 attr.query.prog_attach_flags = ptr_to_u64(OPTS_GET(opts, prog_attach_flags, NULL));
923 attr.query.link_attach_flags = ptr_to_u64(OPTS_GET(opts, link_attach_flags, NULL));
924
925 ret = sys_bpf(BPF_PROG_QUERY, &attr, attr_sz);
926
927 OPTS_SET(opts, attach_flags, attr.query.attach_flags);
928 OPTS_SET(opts, revision, attr.query.revision);
929 OPTS_SET(opts, count, attr.query.count);
930
931 return libbpf_err_errno(ret);
932 }
933
bpf_prog_query(int target_fd,enum bpf_attach_type type,__u32 query_flags,__u32 * attach_flags,__u32 * prog_ids,__u32 * prog_cnt)934 int bpf_prog_query(int target_fd, enum bpf_attach_type type, __u32 query_flags,
935 __u32 *attach_flags, __u32 *prog_ids, __u32 *prog_cnt)
936 {
937 LIBBPF_OPTS(bpf_prog_query_opts, opts);
938 int ret;
939
940 opts.query_flags = query_flags;
941 opts.prog_ids = prog_ids;
942 opts.prog_cnt = *prog_cnt;
943
944 ret = bpf_prog_query_opts(target_fd, type, &opts);
945
946 if (attach_flags)
947 *attach_flags = opts.attach_flags;
948 *prog_cnt = opts.prog_cnt;
949
950 return libbpf_err_errno(ret);
951 }
952
bpf_prog_test_run_opts(int prog_fd,struct bpf_test_run_opts * opts)953 int bpf_prog_test_run_opts(int prog_fd, struct bpf_test_run_opts *opts)
954 {
955 const size_t attr_sz = offsetofend(union bpf_attr, test);
956 union bpf_attr attr;
957 int ret;
958
959 if (!OPTS_VALID(opts, bpf_test_run_opts))
960 return libbpf_err(-EINVAL);
961
962 memset(&attr, 0, attr_sz);
963 attr.test.prog_fd = prog_fd;
964 attr.test.batch_size = OPTS_GET(opts, batch_size, 0);
965 attr.test.cpu = OPTS_GET(opts, cpu, 0);
966 attr.test.flags = OPTS_GET(opts, flags, 0);
967 attr.test.repeat = OPTS_GET(opts, repeat, 0);
968 attr.test.duration = OPTS_GET(opts, duration, 0);
969 attr.test.ctx_size_in = OPTS_GET(opts, ctx_size_in, 0);
970 attr.test.ctx_size_out = OPTS_GET(opts, ctx_size_out, 0);
971 attr.test.data_size_in = OPTS_GET(opts, data_size_in, 0);
972 attr.test.data_size_out = OPTS_GET(opts, data_size_out, 0);
973 attr.test.ctx_in = ptr_to_u64(OPTS_GET(opts, ctx_in, NULL));
974 attr.test.ctx_out = ptr_to_u64(OPTS_GET(opts, ctx_out, NULL));
975 attr.test.data_in = ptr_to_u64(OPTS_GET(opts, data_in, NULL));
976 attr.test.data_out = ptr_to_u64(OPTS_GET(opts, data_out, NULL));
977
978 ret = sys_bpf(BPF_PROG_TEST_RUN, &attr, attr_sz);
979
980 OPTS_SET(opts, data_size_out, attr.test.data_size_out);
981 OPTS_SET(opts, ctx_size_out, attr.test.ctx_size_out);
982 OPTS_SET(opts, duration, attr.test.duration);
983 OPTS_SET(opts, retval, attr.test.retval);
984
985 return libbpf_err_errno(ret);
986 }
987
bpf_obj_get_next_id(__u32 start_id,__u32 * next_id,int cmd)988 static int bpf_obj_get_next_id(__u32 start_id, __u32 *next_id, int cmd)
989 {
990 const size_t attr_sz = offsetofend(union bpf_attr, open_flags);
991 union bpf_attr attr;
992 int err;
993
994 memset(&attr, 0, attr_sz);
995 attr.start_id = start_id;
996
997 err = sys_bpf(cmd, &attr, attr_sz);
998 if (!err)
999 *next_id = attr.next_id;
1000
1001 return libbpf_err_errno(err);
1002 }
1003
bpf_prog_get_next_id(__u32 start_id,__u32 * next_id)1004 int bpf_prog_get_next_id(__u32 start_id, __u32 *next_id)
1005 {
1006 return bpf_obj_get_next_id(start_id, next_id, BPF_PROG_GET_NEXT_ID);
1007 }
1008
bpf_map_get_next_id(__u32 start_id,__u32 * next_id)1009 int bpf_map_get_next_id(__u32 start_id, __u32 *next_id)
1010 {
1011 return bpf_obj_get_next_id(start_id, next_id, BPF_MAP_GET_NEXT_ID);
1012 }
1013
bpf_btf_get_next_id(__u32 start_id,__u32 * next_id)1014 int bpf_btf_get_next_id(__u32 start_id, __u32 *next_id)
1015 {
1016 return bpf_obj_get_next_id(start_id, next_id, BPF_BTF_GET_NEXT_ID);
1017 }
1018
bpf_link_get_next_id(__u32 start_id,__u32 * next_id)1019 int bpf_link_get_next_id(__u32 start_id, __u32 *next_id)
1020 {
1021 return bpf_obj_get_next_id(start_id, next_id, BPF_LINK_GET_NEXT_ID);
1022 }
1023
bpf_prog_get_fd_by_id_opts(__u32 id,const struct bpf_get_fd_by_id_opts * opts)1024 int bpf_prog_get_fd_by_id_opts(__u32 id,
1025 const struct bpf_get_fd_by_id_opts *opts)
1026 {
1027 const size_t attr_sz = offsetofend(union bpf_attr, open_flags);
1028 union bpf_attr attr;
1029 int fd;
1030
1031 if (!OPTS_VALID(opts, bpf_get_fd_by_id_opts))
1032 return libbpf_err(-EINVAL);
1033
1034 memset(&attr, 0, attr_sz);
1035 attr.prog_id = id;
1036 attr.open_flags = OPTS_GET(opts, open_flags, 0);
1037
1038 fd = sys_bpf_fd(BPF_PROG_GET_FD_BY_ID, &attr, attr_sz);
1039 return libbpf_err_errno(fd);
1040 }
1041
bpf_prog_get_fd_by_id(__u32 id)1042 int bpf_prog_get_fd_by_id(__u32 id)
1043 {
1044 return bpf_prog_get_fd_by_id_opts(id, NULL);
1045 }
1046
bpf_map_get_fd_by_id_opts(__u32 id,const struct bpf_get_fd_by_id_opts * opts)1047 int bpf_map_get_fd_by_id_opts(__u32 id,
1048 const struct bpf_get_fd_by_id_opts *opts)
1049 {
1050 const size_t attr_sz = offsetofend(union bpf_attr, open_flags);
1051 union bpf_attr attr;
1052 int fd;
1053
1054 if (!OPTS_VALID(opts, bpf_get_fd_by_id_opts))
1055 return libbpf_err(-EINVAL);
1056
1057 memset(&attr, 0, attr_sz);
1058 attr.map_id = id;
1059 attr.open_flags = OPTS_GET(opts, open_flags, 0);
1060
1061 fd = sys_bpf_fd(BPF_MAP_GET_FD_BY_ID, &attr, attr_sz);
1062 return libbpf_err_errno(fd);
1063 }
1064
bpf_map_get_fd_by_id(__u32 id)1065 int bpf_map_get_fd_by_id(__u32 id)
1066 {
1067 return bpf_map_get_fd_by_id_opts(id, NULL);
1068 }
1069
bpf_btf_get_fd_by_id_opts(__u32 id,const struct bpf_get_fd_by_id_opts * opts)1070 int bpf_btf_get_fd_by_id_opts(__u32 id,
1071 const struct bpf_get_fd_by_id_opts *opts)
1072 {
1073 const size_t attr_sz = offsetofend(union bpf_attr, open_flags);
1074 union bpf_attr attr;
1075 int fd;
1076
1077 if (!OPTS_VALID(opts, bpf_get_fd_by_id_opts))
1078 return libbpf_err(-EINVAL);
1079
1080 memset(&attr, 0, attr_sz);
1081 attr.btf_id = id;
1082 attr.open_flags = OPTS_GET(opts, open_flags, 0);
1083
1084 fd = sys_bpf_fd(BPF_BTF_GET_FD_BY_ID, &attr, attr_sz);
1085 return libbpf_err_errno(fd);
1086 }
1087
bpf_btf_get_fd_by_id(__u32 id)1088 int bpf_btf_get_fd_by_id(__u32 id)
1089 {
1090 return bpf_btf_get_fd_by_id_opts(id, NULL);
1091 }
1092
bpf_link_get_fd_by_id_opts(__u32 id,const struct bpf_get_fd_by_id_opts * opts)1093 int bpf_link_get_fd_by_id_opts(__u32 id,
1094 const struct bpf_get_fd_by_id_opts *opts)
1095 {
1096 const size_t attr_sz = offsetofend(union bpf_attr, open_flags);
1097 union bpf_attr attr;
1098 int fd;
1099
1100 if (!OPTS_VALID(opts, bpf_get_fd_by_id_opts))
1101 return libbpf_err(-EINVAL);
1102
1103 memset(&attr, 0, attr_sz);
1104 attr.link_id = id;
1105 attr.open_flags = OPTS_GET(opts, open_flags, 0);
1106
1107 fd = sys_bpf_fd(BPF_LINK_GET_FD_BY_ID, &attr, attr_sz);
1108 return libbpf_err_errno(fd);
1109 }
1110
bpf_link_get_fd_by_id(__u32 id)1111 int bpf_link_get_fd_by_id(__u32 id)
1112 {
1113 return bpf_link_get_fd_by_id_opts(id, NULL);
1114 }
1115
bpf_obj_get_info_by_fd(int bpf_fd,void * info,__u32 * info_len)1116 int bpf_obj_get_info_by_fd(int bpf_fd, void *info, __u32 *info_len)
1117 {
1118 const size_t attr_sz = offsetofend(union bpf_attr, info);
1119 union bpf_attr attr;
1120 int err;
1121
1122 memset(&attr, 0, attr_sz);
1123 attr.info.bpf_fd = bpf_fd;
1124 attr.info.info_len = *info_len;
1125 attr.info.info = ptr_to_u64(info);
1126
1127 err = sys_bpf(BPF_OBJ_GET_INFO_BY_FD, &attr, attr_sz);
1128 if (!err)
1129 *info_len = attr.info.info_len;
1130 return libbpf_err_errno(err);
1131 }
1132
bpf_prog_get_info_by_fd(int prog_fd,struct bpf_prog_info * info,__u32 * info_len)1133 int bpf_prog_get_info_by_fd(int prog_fd, struct bpf_prog_info *info, __u32 *info_len)
1134 {
1135 return bpf_obj_get_info_by_fd(prog_fd, info, info_len);
1136 }
1137
bpf_map_get_info_by_fd(int map_fd,struct bpf_map_info * info,__u32 * info_len)1138 int bpf_map_get_info_by_fd(int map_fd, struct bpf_map_info *info, __u32 *info_len)
1139 {
1140 return bpf_obj_get_info_by_fd(map_fd, info, info_len);
1141 }
1142
bpf_btf_get_info_by_fd(int btf_fd,struct bpf_btf_info * info,__u32 * info_len)1143 int bpf_btf_get_info_by_fd(int btf_fd, struct bpf_btf_info *info, __u32 *info_len)
1144 {
1145 return bpf_obj_get_info_by_fd(btf_fd, info, info_len);
1146 }
1147
bpf_link_get_info_by_fd(int link_fd,struct bpf_link_info * info,__u32 * info_len)1148 int bpf_link_get_info_by_fd(int link_fd, struct bpf_link_info *info, __u32 *info_len)
1149 {
1150 return bpf_obj_get_info_by_fd(link_fd, info, info_len);
1151 }
1152
bpf_raw_tracepoint_open(const char * name,int prog_fd)1153 int bpf_raw_tracepoint_open(const char *name, int prog_fd)
1154 {
1155 const size_t attr_sz = offsetofend(union bpf_attr, raw_tracepoint);
1156 union bpf_attr attr;
1157 int fd;
1158
1159 memset(&attr, 0, attr_sz);
1160 attr.raw_tracepoint.name = ptr_to_u64(name);
1161 attr.raw_tracepoint.prog_fd = prog_fd;
1162
1163 fd = sys_bpf_fd(BPF_RAW_TRACEPOINT_OPEN, &attr, attr_sz);
1164 return libbpf_err_errno(fd);
1165 }
1166
bpf_btf_load(const void * btf_data,size_t btf_size,struct bpf_btf_load_opts * opts)1167 int bpf_btf_load(const void *btf_data, size_t btf_size, struct bpf_btf_load_opts *opts)
1168 {
1169 const size_t attr_sz = offsetofend(union bpf_attr, btf_log_true_size);
1170 union bpf_attr attr;
1171 char *log_buf;
1172 size_t log_size;
1173 __u32 log_level;
1174 int fd;
1175
1176 bump_rlimit_memlock();
1177
1178 memset(&attr, 0, attr_sz);
1179
1180 if (!OPTS_VALID(opts, bpf_btf_load_opts))
1181 return libbpf_err(-EINVAL);
1182
1183 log_buf = OPTS_GET(opts, log_buf, NULL);
1184 log_size = OPTS_GET(opts, log_size, 0);
1185 log_level = OPTS_GET(opts, log_level, 0);
1186
1187 if (log_size > UINT_MAX)
1188 return libbpf_err(-EINVAL);
1189 if (log_size && !log_buf)
1190 return libbpf_err(-EINVAL);
1191
1192 attr.btf = ptr_to_u64(btf_data);
1193 attr.btf_size = btf_size;
1194 /* log_level == 0 and log_buf != NULL means "try loading without
1195 * log_buf, but retry with log_buf and log_level=1 on error", which is
1196 * consistent across low-level and high-level BTF and program loading
1197 * APIs within libbpf and provides a sensible behavior in practice
1198 */
1199 if (log_level) {
1200 attr.btf_log_buf = ptr_to_u64(log_buf);
1201 attr.btf_log_size = (__u32)log_size;
1202 attr.btf_log_level = log_level;
1203 }
1204
1205 fd = sys_bpf_fd(BPF_BTF_LOAD, &attr, attr_sz);
1206 if (fd < 0 && log_buf && log_level == 0) {
1207 attr.btf_log_buf = ptr_to_u64(log_buf);
1208 attr.btf_log_size = (__u32)log_size;
1209 attr.btf_log_level = 1;
1210 fd = sys_bpf_fd(BPF_BTF_LOAD, &attr, attr_sz);
1211 }
1212
1213 OPTS_SET(opts, log_true_size, attr.btf_log_true_size);
1214 return libbpf_err_errno(fd);
1215 }
1216
bpf_task_fd_query(int pid,int fd,__u32 flags,char * buf,__u32 * buf_len,__u32 * prog_id,__u32 * fd_type,__u64 * probe_offset,__u64 * probe_addr)1217 int bpf_task_fd_query(int pid, int fd, __u32 flags, char *buf, __u32 *buf_len,
1218 __u32 *prog_id, __u32 *fd_type, __u64 *probe_offset,
1219 __u64 *probe_addr)
1220 {
1221 const size_t attr_sz = offsetofend(union bpf_attr, task_fd_query);
1222 union bpf_attr attr;
1223 int err;
1224
1225 memset(&attr, 0, attr_sz);
1226 attr.task_fd_query.pid = pid;
1227 attr.task_fd_query.fd = fd;
1228 attr.task_fd_query.flags = flags;
1229 attr.task_fd_query.buf = ptr_to_u64(buf);
1230 attr.task_fd_query.buf_len = *buf_len;
1231
1232 err = sys_bpf(BPF_TASK_FD_QUERY, &attr, attr_sz);
1233
1234 *buf_len = attr.task_fd_query.buf_len;
1235 *prog_id = attr.task_fd_query.prog_id;
1236 *fd_type = attr.task_fd_query.fd_type;
1237 *probe_offset = attr.task_fd_query.probe_offset;
1238 *probe_addr = attr.task_fd_query.probe_addr;
1239
1240 return libbpf_err_errno(err);
1241 }
1242
bpf_enable_stats(enum bpf_stats_type type)1243 int bpf_enable_stats(enum bpf_stats_type type)
1244 {
1245 const size_t attr_sz = offsetofend(union bpf_attr, enable_stats);
1246 union bpf_attr attr;
1247 int fd;
1248
1249 memset(&attr, 0, attr_sz);
1250 attr.enable_stats.type = type;
1251
1252 fd = sys_bpf_fd(BPF_ENABLE_STATS, &attr, attr_sz);
1253 return libbpf_err_errno(fd);
1254 }
1255
bpf_prog_bind_map(int prog_fd,int map_fd,const struct bpf_prog_bind_opts * opts)1256 int bpf_prog_bind_map(int prog_fd, int map_fd,
1257 const struct bpf_prog_bind_opts *opts)
1258 {
1259 const size_t attr_sz = offsetofend(union bpf_attr, prog_bind_map);
1260 union bpf_attr attr;
1261 int ret;
1262
1263 if (!OPTS_VALID(opts, bpf_prog_bind_opts))
1264 return libbpf_err(-EINVAL);
1265
1266 memset(&attr, 0, attr_sz);
1267 attr.prog_bind_map.prog_fd = prog_fd;
1268 attr.prog_bind_map.map_fd = map_fd;
1269 attr.prog_bind_map.flags = OPTS_GET(opts, flags, 0);
1270
1271 ret = sys_bpf(BPF_PROG_BIND_MAP, &attr, attr_sz);
1272 return libbpf_err_errno(ret);
1273 }
1274