xref: /linux/tools/lib/bpf/bpf.c (revision be239684b18e1cdcafcf8c7face4a2f562c745ad)
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 
67 static inline __u64 ptr_to_u64(const void *ptr)
68 {
69 	return (__u64) (unsigned long) ptr;
70 }
71 
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 
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 
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  */
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 
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 
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 
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 *
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 
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 
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 
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 
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 
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 
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 
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 
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 
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 
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 
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 
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 
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 
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 
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 
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 
594 int bpf_obj_pin(int fd, const char *pathname)
595 {
596 	return bpf_obj_pin_opts(fd, pathname, NULL);
597 }
598 
599 int bpf_obj_get(const char *pathname)
600 {
601 	return bpf_obj_get_opts(pathname, NULL);
602 }
603 
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 
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 
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 
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 
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 
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 
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 	case BPF_NETKIT_PRIMARY:
814 	case BPF_NETKIT_PEER:
815 		relative_fd = OPTS_GET(opts, netkit.relative_fd, 0);
816 		relative_id = OPTS_GET(opts, netkit.relative_id, 0);
817 		if (relative_fd && relative_id)
818 			return libbpf_err(-EINVAL);
819 		if (relative_id) {
820 			attr.link_create.netkit.relative_id = relative_id;
821 			attr.link_create.flags |= BPF_F_ID;
822 		} else {
823 			attr.link_create.netkit.relative_fd = relative_fd;
824 		}
825 		attr.link_create.netkit.expected_revision = OPTS_GET(opts, netkit.expected_revision, 0);
826 		if (!OPTS_ZEROED(opts, netkit))
827 			return libbpf_err(-EINVAL);
828 		break;
829 	default:
830 		if (!OPTS_ZEROED(opts, flags))
831 			return libbpf_err(-EINVAL);
832 		break;
833 	}
834 proceed:
835 	fd = sys_bpf_fd(BPF_LINK_CREATE, &attr, attr_sz);
836 	if (fd >= 0)
837 		return fd;
838 	/* we'll get EINVAL if LINK_CREATE doesn't support attaching fentry
839 	 * and other similar programs
840 	 */
841 	err = -errno;
842 	if (err != -EINVAL)
843 		return libbpf_err(err);
844 
845 	/* if user used features not supported by
846 	 * BPF_RAW_TRACEPOINT_OPEN command, then just give up immediately
847 	 */
848 	if (attr.link_create.target_fd || attr.link_create.target_btf_id)
849 		return libbpf_err(err);
850 	if (!OPTS_ZEROED(opts, sz))
851 		return libbpf_err(err);
852 
853 	/* otherwise, for few select kinds of programs that can be
854 	 * attached using BPF_RAW_TRACEPOINT_OPEN command, try that as
855 	 * a fallback for older kernels
856 	 */
857 	switch (attach_type) {
858 	case BPF_TRACE_RAW_TP:
859 	case BPF_LSM_MAC:
860 	case BPF_TRACE_FENTRY:
861 	case BPF_TRACE_FEXIT:
862 	case BPF_MODIFY_RETURN:
863 		return bpf_raw_tracepoint_open(NULL, prog_fd);
864 	default:
865 		return libbpf_err(err);
866 	}
867 }
868 
869 int bpf_link_detach(int link_fd)
870 {
871 	const size_t attr_sz = offsetofend(union bpf_attr, link_detach);
872 	union bpf_attr attr;
873 	int ret;
874 
875 	memset(&attr, 0, attr_sz);
876 	attr.link_detach.link_fd = link_fd;
877 
878 	ret = sys_bpf(BPF_LINK_DETACH, &attr, attr_sz);
879 	return libbpf_err_errno(ret);
880 }
881 
882 int bpf_link_update(int link_fd, int new_prog_fd,
883 		    const struct bpf_link_update_opts *opts)
884 {
885 	const size_t attr_sz = offsetofend(union bpf_attr, link_update);
886 	union bpf_attr attr;
887 	int ret;
888 
889 	if (!OPTS_VALID(opts, bpf_link_update_opts))
890 		return libbpf_err(-EINVAL);
891 
892 	if (OPTS_GET(opts, old_prog_fd, 0) && OPTS_GET(opts, old_map_fd, 0))
893 		return libbpf_err(-EINVAL);
894 
895 	memset(&attr, 0, attr_sz);
896 	attr.link_update.link_fd = link_fd;
897 	attr.link_update.new_prog_fd = new_prog_fd;
898 	attr.link_update.flags = OPTS_GET(opts, flags, 0);
899 	if (OPTS_GET(opts, old_prog_fd, 0))
900 		attr.link_update.old_prog_fd = OPTS_GET(opts, old_prog_fd, 0);
901 	else if (OPTS_GET(opts, old_map_fd, 0))
902 		attr.link_update.old_map_fd = OPTS_GET(opts, old_map_fd, 0);
903 
904 	ret = sys_bpf(BPF_LINK_UPDATE, &attr, attr_sz);
905 	return libbpf_err_errno(ret);
906 }
907 
908 int bpf_iter_create(int link_fd)
909 {
910 	const size_t attr_sz = offsetofend(union bpf_attr, iter_create);
911 	union bpf_attr attr;
912 	int fd;
913 
914 	memset(&attr, 0, attr_sz);
915 	attr.iter_create.link_fd = link_fd;
916 
917 	fd = sys_bpf_fd(BPF_ITER_CREATE, &attr, attr_sz);
918 	return libbpf_err_errno(fd);
919 }
920 
921 int bpf_prog_query_opts(int target, enum bpf_attach_type type,
922 			struct bpf_prog_query_opts *opts)
923 {
924 	const size_t attr_sz = offsetofend(union bpf_attr, query);
925 	union bpf_attr attr;
926 	int ret;
927 
928 	if (!OPTS_VALID(opts, bpf_prog_query_opts))
929 		return libbpf_err(-EINVAL);
930 
931 	memset(&attr, 0, attr_sz);
932 	attr.query.target_fd		= target;
933 	attr.query.attach_type		= type;
934 	attr.query.query_flags		= OPTS_GET(opts, query_flags, 0);
935 	attr.query.count		= OPTS_GET(opts, count, 0);
936 	attr.query.prog_ids		= ptr_to_u64(OPTS_GET(opts, prog_ids, NULL));
937 	attr.query.link_ids		= ptr_to_u64(OPTS_GET(opts, link_ids, NULL));
938 	attr.query.prog_attach_flags	= ptr_to_u64(OPTS_GET(opts, prog_attach_flags, NULL));
939 	attr.query.link_attach_flags	= ptr_to_u64(OPTS_GET(opts, link_attach_flags, NULL));
940 
941 	ret = sys_bpf(BPF_PROG_QUERY, &attr, attr_sz);
942 
943 	OPTS_SET(opts, attach_flags, attr.query.attach_flags);
944 	OPTS_SET(opts, revision, attr.query.revision);
945 	OPTS_SET(opts, count, attr.query.count);
946 
947 	return libbpf_err_errno(ret);
948 }
949 
950 int bpf_prog_query(int target_fd, enum bpf_attach_type type, __u32 query_flags,
951 		   __u32 *attach_flags, __u32 *prog_ids, __u32 *prog_cnt)
952 {
953 	LIBBPF_OPTS(bpf_prog_query_opts, opts);
954 	int ret;
955 
956 	opts.query_flags = query_flags;
957 	opts.prog_ids = prog_ids;
958 	opts.prog_cnt = *prog_cnt;
959 
960 	ret = bpf_prog_query_opts(target_fd, type, &opts);
961 
962 	if (attach_flags)
963 		*attach_flags = opts.attach_flags;
964 	*prog_cnt = opts.prog_cnt;
965 
966 	return libbpf_err_errno(ret);
967 }
968 
969 int bpf_prog_test_run_opts(int prog_fd, struct bpf_test_run_opts *opts)
970 {
971 	const size_t attr_sz = offsetofend(union bpf_attr, test);
972 	union bpf_attr attr;
973 	int ret;
974 
975 	if (!OPTS_VALID(opts, bpf_test_run_opts))
976 		return libbpf_err(-EINVAL);
977 
978 	memset(&attr, 0, attr_sz);
979 	attr.test.prog_fd = prog_fd;
980 	attr.test.batch_size = OPTS_GET(opts, batch_size, 0);
981 	attr.test.cpu = OPTS_GET(opts, cpu, 0);
982 	attr.test.flags = OPTS_GET(opts, flags, 0);
983 	attr.test.repeat = OPTS_GET(opts, repeat, 0);
984 	attr.test.duration = OPTS_GET(opts, duration, 0);
985 	attr.test.ctx_size_in = OPTS_GET(opts, ctx_size_in, 0);
986 	attr.test.ctx_size_out = OPTS_GET(opts, ctx_size_out, 0);
987 	attr.test.data_size_in = OPTS_GET(opts, data_size_in, 0);
988 	attr.test.data_size_out = OPTS_GET(opts, data_size_out, 0);
989 	attr.test.ctx_in = ptr_to_u64(OPTS_GET(opts, ctx_in, NULL));
990 	attr.test.ctx_out = ptr_to_u64(OPTS_GET(opts, ctx_out, NULL));
991 	attr.test.data_in = ptr_to_u64(OPTS_GET(opts, data_in, NULL));
992 	attr.test.data_out = ptr_to_u64(OPTS_GET(opts, data_out, NULL));
993 
994 	ret = sys_bpf(BPF_PROG_TEST_RUN, &attr, attr_sz);
995 
996 	OPTS_SET(opts, data_size_out, attr.test.data_size_out);
997 	OPTS_SET(opts, ctx_size_out, attr.test.ctx_size_out);
998 	OPTS_SET(opts, duration, attr.test.duration);
999 	OPTS_SET(opts, retval, attr.test.retval);
1000 
1001 	return libbpf_err_errno(ret);
1002 }
1003 
1004 static int bpf_obj_get_next_id(__u32 start_id, __u32 *next_id, int cmd)
1005 {
1006 	const size_t attr_sz = offsetofend(union bpf_attr, open_flags);
1007 	union bpf_attr attr;
1008 	int err;
1009 
1010 	memset(&attr, 0, attr_sz);
1011 	attr.start_id = start_id;
1012 
1013 	err = sys_bpf(cmd, &attr, attr_sz);
1014 	if (!err)
1015 		*next_id = attr.next_id;
1016 
1017 	return libbpf_err_errno(err);
1018 }
1019 
1020 int bpf_prog_get_next_id(__u32 start_id, __u32 *next_id)
1021 {
1022 	return bpf_obj_get_next_id(start_id, next_id, BPF_PROG_GET_NEXT_ID);
1023 }
1024 
1025 int bpf_map_get_next_id(__u32 start_id, __u32 *next_id)
1026 {
1027 	return bpf_obj_get_next_id(start_id, next_id, BPF_MAP_GET_NEXT_ID);
1028 }
1029 
1030 int bpf_btf_get_next_id(__u32 start_id, __u32 *next_id)
1031 {
1032 	return bpf_obj_get_next_id(start_id, next_id, BPF_BTF_GET_NEXT_ID);
1033 }
1034 
1035 int bpf_link_get_next_id(__u32 start_id, __u32 *next_id)
1036 {
1037 	return bpf_obj_get_next_id(start_id, next_id, BPF_LINK_GET_NEXT_ID);
1038 }
1039 
1040 int bpf_prog_get_fd_by_id_opts(__u32 id,
1041 			       const struct bpf_get_fd_by_id_opts *opts)
1042 {
1043 	const size_t attr_sz = offsetofend(union bpf_attr, open_flags);
1044 	union bpf_attr attr;
1045 	int fd;
1046 
1047 	if (!OPTS_VALID(opts, bpf_get_fd_by_id_opts))
1048 		return libbpf_err(-EINVAL);
1049 
1050 	memset(&attr, 0, attr_sz);
1051 	attr.prog_id = id;
1052 	attr.open_flags = OPTS_GET(opts, open_flags, 0);
1053 
1054 	fd = sys_bpf_fd(BPF_PROG_GET_FD_BY_ID, &attr, attr_sz);
1055 	return libbpf_err_errno(fd);
1056 }
1057 
1058 int bpf_prog_get_fd_by_id(__u32 id)
1059 {
1060 	return bpf_prog_get_fd_by_id_opts(id, NULL);
1061 }
1062 
1063 int bpf_map_get_fd_by_id_opts(__u32 id,
1064 			      const struct bpf_get_fd_by_id_opts *opts)
1065 {
1066 	const size_t attr_sz = offsetofend(union bpf_attr, open_flags);
1067 	union bpf_attr attr;
1068 	int fd;
1069 
1070 	if (!OPTS_VALID(opts, bpf_get_fd_by_id_opts))
1071 		return libbpf_err(-EINVAL);
1072 
1073 	memset(&attr, 0, attr_sz);
1074 	attr.map_id = id;
1075 	attr.open_flags = OPTS_GET(opts, open_flags, 0);
1076 
1077 	fd = sys_bpf_fd(BPF_MAP_GET_FD_BY_ID, &attr, attr_sz);
1078 	return libbpf_err_errno(fd);
1079 }
1080 
1081 int bpf_map_get_fd_by_id(__u32 id)
1082 {
1083 	return bpf_map_get_fd_by_id_opts(id, NULL);
1084 }
1085 
1086 int bpf_btf_get_fd_by_id_opts(__u32 id,
1087 			      const struct bpf_get_fd_by_id_opts *opts)
1088 {
1089 	const size_t attr_sz = offsetofend(union bpf_attr, open_flags);
1090 	union bpf_attr attr;
1091 	int fd;
1092 
1093 	if (!OPTS_VALID(opts, bpf_get_fd_by_id_opts))
1094 		return libbpf_err(-EINVAL);
1095 
1096 	memset(&attr, 0, attr_sz);
1097 	attr.btf_id = id;
1098 	attr.open_flags = OPTS_GET(opts, open_flags, 0);
1099 
1100 	fd = sys_bpf_fd(BPF_BTF_GET_FD_BY_ID, &attr, attr_sz);
1101 	return libbpf_err_errno(fd);
1102 }
1103 
1104 int bpf_btf_get_fd_by_id(__u32 id)
1105 {
1106 	return bpf_btf_get_fd_by_id_opts(id, NULL);
1107 }
1108 
1109 int bpf_link_get_fd_by_id_opts(__u32 id,
1110 			       const struct bpf_get_fd_by_id_opts *opts)
1111 {
1112 	const size_t attr_sz = offsetofend(union bpf_attr, open_flags);
1113 	union bpf_attr attr;
1114 	int fd;
1115 
1116 	if (!OPTS_VALID(opts, bpf_get_fd_by_id_opts))
1117 		return libbpf_err(-EINVAL);
1118 
1119 	memset(&attr, 0, attr_sz);
1120 	attr.link_id = id;
1121 	attr.open_flags = OPTS_GET(opts, open_flags, 0);
1122 
1123 	fd = sys_bpf_fd(BPF_LINK_GET_FD_BY_ID, &attr, attr_sz);
1124 	return libbpf_err_errno(fd);
1125 }
1126 
1127 int bpf_link_get_fd_by_id(__u32 id)
1128 {
1129 	return bpf_link_get_fd_by_id_opts(id, NULL);
1130 }
1131 
1132 int bpf_obj_get_info_by_fd(int bpf_fd, void *info, __u32 *info_len)
1133 {
1134 	const size_t attr_sz = offsetofend(union bpf_attr, info);
1135 	union bpf_attr attr;
1136 	int err;
1137 
1138 	memset(&attr, 0, attr_sz);
1139 	attr.info.bpf_fd = bpf_fd;
1140 	attr.info.info_len = *info_len;
1141 	attr.info.info = ptr_to_u64(info);
1142 
1143 	err = sys_bpf(BPF_OBJ_GET_INFO_BY_FD, &attr, attr_sz);
1144 	if (!err)
1145 		*info_len = attr.info.info_len;
1146 	return libbpf_err_errno(err);
1147 }
1148 
1149 int bpf_prog_get_info_by_fd(int prog_fd, struct bpf_prog_info *info, __u32 *info_len)
1150 {
1151 	return bpf_obj_get_info_by_fd(prog_fd, info, info_len);
1152 }
1153 
1154 int bpf_map_get_info_by_fd(int map_fd, struct bpf_map_info *info, __u32 *info_len)
1155 {
1156 	return bpf_obj_get_info_by_fd(map_fd, info, info_len);
1157 }
1158 
1159 int bpf_btf_get_info_by_fd(int btf_fd, struct bpf_btf_info *info, __u32 *info_len)
1160 {
1161 	return bpf_obj_get_info_by_fd(btf_fd, info, info_len);
1162 }
1163 
1164 int bpf_link_get_info_by_fd(int link_fd, struct bpf_link_info *info, __u32 *info_len)
1165 {
1166 	return bpf_obj_get_info_by_fd(link_fd, info, info_len);
1167 }
1168 
1169 int bpf_raw_tracepoint_open(const char *name, int prog_fd)
1170 {
1171 	const size_t attr_sz = offsetofend(union bpf_attr, raw_tracepoint);
1172 	union bpf_attr attr;
1173 	int fd;
1174 
1175 	memset(&attr, 0, attr_sz);
1176 	attr.raw_tracepoint.name = ptr_to_u64(name);
1177 	attr.raw_tracepoint.prog_fd = prog_fd;
1178 
1179 	fd = sys_bpf_fd(BPF_RAW_TRACEPOINT_OPEN, &attr, attr_sz);
1180 	return libbpf_err_errno(fd);
1181 }
1182 
1183 int bpf_btf_load(const void *btf_data, size_t btf_size, struct bpf_btf_load_opts *opts)
1184 {
1185 	const size_t attr_sz = offsetofend(union bpf_attr, btf_log_true_size);
1186 	union bpf_attr attr;
1187 	char *log_buf;
1188 	size_t log_size;
1189 	__u32 log_level;
1190 	int fd;
1191 
1192 	bump_rlimit_memlock();
1193 
1194 	memset(&attr, 0, attr_sz);
1195 
1196 	if (!OPTS_VALID(opts, bpf_btf_load_opts))
1197 		return libbpf_err(-EINVAL);
1198 
1199 	log_buf = OPTS_GET(opts, log_buf, NULL);
1200 	log_size = OPTS_GET(opts, log_size, 0);
1201 	log_level = OPTS_GET(opts, log_level, 0);
1202 
1203 	if (log_size > UINT_MAX)
1204 		return libbpf_err(-EINVAL);
1205 	if (log_size && !log_buf)
1206 		return libbpf_err(-EINVAL);
1207 
1208 	attr.btf = ptr_to_u64(btf_data);
1209 	attr.btf_size = btf_size;
1210 	/* log_level == 0 and log_buf != NULL means "try loading without
1211 	 * log_buf, but retry with log_buf and log_level=1 on error", which is
1212 	 * consistent across low-level and high-level BTF and program loading
1213 	 * APIs within libbpf and provides a sensible behavior in practice
1214 	 */
1215 	if (log_level) {
1216 		attr.btf_log_buf = ptr_to_u64(log_buf);
1217 		attr.btf_log_size = (__u32)log_size;
1218 		attr.btf_log_level = log_level;
1219 	}
1220 
1221 	fd = sys_bpf_fd(BPF_BTF_LOAD, &attr, attr_sz);
1222 	if (fd < 0 && log_buf && log_level == 0) {
1223 		attr.btf_log_buf = ptr_to_u64(log_buf);
1224 		attr.btf_log_size = (__u32)log_size;
1225 		attr.btf_log_level = 1;
1226 		fd = sys_bpf_fd(BPF_BTF_LOAD, &attr, attr_sz);
1227 	}
1228 
1229 	OPTS_SET(opts, log_true_size, attr.btf_log_true_size);
1230 	return libbpf_err_errno(fd);
1231 }
1232 
1233 int bpf_task_fd_query(int pid, int fd, __u32 flags, char *buf, __u32 *buf_len,
1234 		      __u32 *prog_id, __u32 *fd_type, __u64 *probe_offset,
1235 		      __u64 *probe_addr)
1236 {
1237 	const size_t attr_sz = offsetofend(union bpf_attr, task_fd_query);
1238 	union bpf_attr attr;
1239 	int err;
1240 
1241 	memset(&attr, 0, attr_sz);
1242 	attr.task_fd_query.pid = pid;
1243 	attr.task_fd_query.fd = fd;
1244 	attr.task_fd_query.flags = flags;
1245 	attr.task_fd_query.buf = ptr_to_u64(buf);
1246 	attr.task_fd_query.buf_len = *buf_len;
1247 
1248 	err = sys_bpf(BPF_TASK_FD_QUERY, &attr, attr_sz);
1249 
1250 	*buf_len = attr.task_fd_query.buf_len;
1251 	*prog_id = attr.task_fd_query.prog_id;
1252 	*fd_type = attr.task_fd_query.fd_type;
1253 	*probe_offset = attr.task_fd_query.probe_offset;
1254 	*probe_addr = attr.task_fd_query.probe_addr;
1255 
1256 	return libbpf_err_errno(err);
1257 }
1258 
1259 int bpf_enable_stats(enum bpf_stats_type type)
1260 {
1261 	const size_t attr_sz = offsetofend(union bpf_attr, enable_stats);
1262 	union bpf_attr attr;
1263 	int fd;
1264 
1265 	memset(&attr, 0, attr_sz);
1266 	attr.enable_stats.type = type;
1267 
1268 	fd = sys_bpf_fd(BPF_ENABLE_STATS, &attr, attr_sz);
1269 	return libbpf_err_errno(fd);
1270 }
1271 
1272 int bpf_prog_bind_map(int prog_fd, int map_fd,
1273 		      const struct bpf_prog_bind_opts *opts)
1274 {
1275 	const size_t attr_sz = offsetofend(union bpf_attr, prog_bind_map);
1276 	union bpf_attr attr;
1277 	int ret;
1278 
1279 	if (!OPTS_VALID(opts, bpf_prog_bind_opts))
1280 		return libbpf_err(-EINVAL);
1281 
1282 	memset(&attr, 0, attr_sz);
1283 	attr.prog_bind_map.prog_fd = prog_fd;
1284 	attr.prog_bind_map.map_fd = map_fd;
1285 	attr.prog_bind_map.flags = OPTS_GET(opts, flags, 0);
1286 
1287 	ret = sys_bpf(BPF_PROG_BIND_MAP, &attr, attr_sz);
1288 	return libbpf_err_errno(ret);
1289 }
1290