1 // SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
4 * common eBPF ELF operations.
6 * Copyright (C) 2013-2015 Alexei Starovoitov <ast@kernel.org>
7 * Copyright (C) 2015 Wang Nan <wangnan0@huawei.com>
8 * Copyright (C) 2015 Huawei Inc.
10 * This program is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU Lesser General Public
12 * License as published by the Free Software Foundation;
13 * version 2.1 of the License (not later!)
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU Lesser General Public License for more details.
20 * You should have received a copy of the GNU Lesser General Public
21 * License along with this program; if not, see <http://www.gnu.org/licenses>
28 #include <asm/unistd.h>
30 #include <linux/bpf.h>
33 #include "libbpf_internal.h"
36 * When building perf, unistd.h is overridden. __NR_bpf is
37 * required to be defined explicitly.
40 # if defined(__i386__)
42 # elif defined(__x86_64__)
44 # elif defined(__aarch64__)
46 # elif defined(__sparc__)
48 # elif defined(__s390__)
50 # elif defined(__arc__)
53 # error __NR_bpf not defined. libbpf does not support your arch.
57 static inline __u64 ptr_to_u64(const void *ptr)
59 return (__u64) (unsigned long) ptr;
62 static inline int sys_bpf(enum bpf_cmd cmd, union bpf_attr *attr,
65 return syscall(__NR_bpf, cmd, attr, size);
68 static inline int sys_bpf_prog_load(union bpf_attr *attr, unsigned int size)
73 fd = sys_bpf(BPF_PROG_LOAD, attr, size);
74 } while (fd < 0 && errno == EAGAIN);
79 int bpf_create_map_xattr(const struct bpf_create_map_attr *create_attr)
83 memset(&attr, '\0', sizeof(attr));
85 attr.map_type = create_attr->map_type;
86 attr.key_size = create_attr->key_size;
87 attr.value_size = create_attr->value_size;
88 attr.max_entries = create_attr->max_entries;
89 attr.map_flags = create_attr->map_flags;
90 if (create_attr->name)
91 memcpy(attr.map_name, create_attr->name,
92 min(strlen(create_attr->name), BPF_OBJ_NAME_LEN - 1));
93 attr.numa_node = create_attr->numa_node;
94 attr.btf_fd = create_attr->btf_fd;
95 attr.btf_key_type_id = create_attr->btf_key_type_id;
96 attr.btf_value_type_id = create_attr->btf_value_type_id;
97 attr.map_ifindex = create_attr->map_ifindex;
98 attr.inner_map_fd = create_attr->inner_map_fd;
100 return sys_bpf(BPF_MAP_CREATE, &attr, sizeof(attr));
103 int bpf_create_map_node(enum bpf_map_type map_type, const char *name,
104 int key_size, int value_size, int max_entries,
105 __u32 map_flags, int node)
107 struct bpf_create_map_attr map_attr = {};
109 map_attr.name = name;
110 map_attr.map_type = map_type;
111 map_attr.map_flags = map_flags;
112 map_attr.key_size = key_size;
113 map_attr.value_size = value_size;
114 map_attr.max_entries = max_entries;
116 map_attr.numa_node = node;
117 map_attr.map_flags |= BPF_F_NUMA_NODE;
120 return bpf_create_map_xattr(&map_attr);
123 int bpf_create_map(enum bpf_map_type map_type, int key_size,
124 int value_size, int max_entries, __u32 map_flags)
126 struct bpf_create_map_attr map_attr = {};
128 map_attr.map_type = map_type;
129 map_attr.map_flags = map_flags;
130 map_attr.key_size = key_size;
131 map_attr.value_size = value_size;
132 map_attr.max_entries = max_entries;
134 return bpf_create_map_xattr(&map_attr);
137 int bpf_create_map_name(enum bpf_map_type map_type, const char *name,
138 int key_size, int value_size, int max_entries,
141 struct bpf_create_map_attr map_attr = {};
143 map_attr.name = name;
144 map_attr.map_type = map_type;
145 map_attr.map_flags = map_flags;
146 map_attr.key_size = key_size;
147 map_attr.value_size = value_size;
148 map_attr.max_entries = max_entries;
150 return bpf_create_map_xattr(&map_attr);
153 int bpf_create_map_in_map_node(enum bpf_map_type map_type, const char *name,
154 int key_size, int inner_map_fd, int max_entries,
155 __u32 map_flags, int node)
159 memset(&attr, '\0', sizeof(attr));
161 attr.map_type = map_type;
162 attr.key_size = key_size;
164 attr.inner_map_fd = inner_map_fd;
165 attr.max_entries = max_entries;
166 attr.map_flags = map_flags;
168 memcpy(attr.map_name, name,
169 min(strlen(name), BPF_OBJ_NAME_LEN - 1));
172 attr.map_flags |= BPF_F_NUMA_NODE;
173 attr.numa_node = node;
176 return sys_bpf(BPF_MAP_CREATE, &attr, sizeof(attr));
179 int bpf_create_map_in_map(enum bpf_map_type map_type, const char *name,
180 int key_size, int inner_map_fd, int max_entries,
183 return bpf_create_map_in_map_node(map_type, name, key_size,
184 inner_map_fd, max_entries, map_flags,
189 alloc_zero_tailing_info(const void *orecord, __u32 cnt,
190 __u32 actual_rec_size, __u32 expected_rec_size)
192 __u64 info_len = actual_rec_size * cnt;
193 void *info, *nrecord;
196 info = malloc(info_len);
200 /* zero out bytes kernel does not understand */
202 for (i = 0; i < cnt; i++) {
203 memcpy(nrecord, orecord, expected_rec_size);
204 memset(nrecord + expected_rec_size, 0,
205 actual_rec_size - expected_rec_size);
206 orecord += actual_rec_size;
207 nrecord += actual_rec_size;
213 int bpf_load_program_xattr(const struct bpf_load_program_attr *load_attr,
214 char *log_buf, size_t log_buf_sz)
216 void *finfo = NULL, *linfo = NULL;
221 if (!load_attr || !log_buf != !log_buf_sz)
224 log_level = load_attr->log_level;
225 if (log_level > (4 | 2 | 1) || (log_level && !log_buf))
228 memset(&attr, 0, sizeof(attr));
229 attr.prog_type = load_attr->prog_type;
230 attr.expected_attach_type = load_attr->expected_attach_type;
231 if (attr.prog_type == BPF_PROG_TYPE_RAW_TRACEPOINT)
232 /* expected_attach_type is ignored for tracing progs */
233 attr.attach_btf_id = attr.expected_attach_type;
234 attr.insn_cnt = (__u32)load_attr->insns_cnt;
235 attr.insns = ptr_to_u64(load_attr->insns);
236 attr.license = ptr_to_u64(load_attr->license);
238 attr.log_level = log_level;
240 attr.log_buf = ptr_to_u64(log_buf);
241 attr.log_size = log_buf_sz;
243 attr.log_buf = ptr_to_u64(NULL);
247 attr.kern_version = load_attr->kern_version;
248 attr.prog_ifindex = load_attr->prog_ifindex;
249 attr.prog_btf_fd = load_attr->prog_btf_fd;
250 attr.func_info_rec_size = load_attr->func_info_rec_size;
251 attr.func_info_cnt = load_attr->func_info_cnt;
252 attr.func_info = ptr_to_u64(load_attr->func_info);
253 attr.line_info_rec_size = load_attr->line_info_rec_size;
254 attr.line_info_cnt = load_attr->line_info_cnt;
255 attr.line_info = ptr_to_u64(load_attr->line_info);
257 memcpy(attr.prog_name, load_attr->name,
258 min(strlen(load_attr->name), BPF_OBJ_NAME_LEN - 1));
259 attr.prog_flags = load_attr->prog_flags;
261 fd = sys_bpf_prog_load(&attr, sizeof(attr));
265 /* After bpf_prog_load, the kernel may modify certain attributes
266 * to give user space a hint how to deal with loading failure.
267 * Check to see whether we can make some changes and load again.
269 while (errno == E2BIG && (!finfo || !linfo)) {
270 if (!finfo && attr.func_info_cnt &&
271 attr.func_info_rec_size < load_attr->func_info_rec_size) {
272 /* try with corrected func info records */
273 finfo = alloc_zero_tailing_info(load_attr->func_info,
274 load_attr->func_info_cnt,
275 load_attr->func_info_rec_size,
276 attr.func_info_rec_size);
280 attr.func_info = ptr_to_u64(finfo);
281 attr.func_info_rec_size = load_attr->func_info_rec_size;
282 } else if (!linfo && attr.line_info_cnt &&
283 attr.line_info_rec_size <
284 load_attr->line_info_rec_size) {
285 linfo = alloc_zero_tailing_info(load_attr->line_info,
286 load_attr->line_info_cnt,
287 load_attr->line_info_rec_size,
288 attr.line_info_rec_size);
292 attr.line_info = ptr_to_u64(linfo);
293 attr.line_info_rec_size = load_attr->line_info_rec_size;
298 fd = sys_bpf_prog_load(&attr, sizeof(attr));
304 if (log_level || !log_buf)
307 /* Try again with log */
308 attr.log_buf = ptr_to_u64(log_buf);
309 attr.log_size = log_buf_sz;
312 fd = sys_bpf_prog_load(&attr, sizeof(attr));
319 int bpf_load_program(enum bpf_prog_type type, const struct bpf_insn *insns,
320 size_t insns_cnt, const char *license,
321 __u32 kern_version, char *log_buf,
324 struct bpf_load_program_attr load_attr;
326 memset(&load_attr, 0, sizeof(struct bpf_load_program_attr));
327 load_attr.prog_type = type;
328 load_attr.expected_attach_type = 0;
329 load_attr.name = NULL;
330 load_attr.insns = insns;
331 load_attr.insns_cnt = insns_cnt;
332 load_attr.license = license;
333 load_attr.kern_version = kern_version;
335 return bpf_load_program_xattr(&load_attr, log_buf, log_buf_sz);
338 int bpf_verify_program(enum bpf_prog_type type, const struct bpf_insn *insns,
339 size_t insns_cnt, __u32 prog_flags, const char *license,
340 __u32 kern_version, char *log_buf, size_t log_buf_sz,
345 memset(&attr, 0, sizeof(attr));
346 attr.prog_type = type;
347 attr.insn_cnt = (__u32)insns_cnt;
348 attr.insns = ptr_to_u64(insns);
349 attr.license = ptr_to_u64(license);
350 attr.log_buf = ptr_to_u64(log_buf);
351 attr.log_size = log_buf_sz;
352 attr.log_level = log_level;
354 attr.kern_version = kern_version;
355 attr.prog_flags = prog_flags;
357 return sys_bpf_prog_load(&attr, sizeof(attr));
360 int bpf_map_update_elem(int fd, const void *key, const void *value,
365 memset(&attr, 0, sizeof(attr));
367 attr.key = ptr_to_u64(key);
368 attr.value = ptr_to_u64(value);
371 return sys_bpf(BPF_MAP_UPDATE_ELEM, &attr, sizeof(attr));
374 int bpf_map_lookup_elem(int fd, const void *key, void *value)
378 memset(&attr, 0, sizeof(attr));
380 attr.key = ptr_to_u64(key);
381 attr.value = ptr_to_u64(value);
383 return sys_bpf(BPF_MAP_LOOKUP_ELEM, &attr, sizeof(attr));
386 int bpf_map_lookup_elem_flags(int fd, const void *key, void *value, __u64 flags)
390 memset(&attr, 0, sizeof(attr));
392 attr.key = ptr_to_u64(key);
393 attr.value = ptr_to_u64(value);
396 return sys_bpf(BPF_MAP_LOOKUP_ELEM, &attr, sizeof(attr));
399 int bpf_map_lookup_and_delete_elem(int fd, const void *key, void *value)
403 memset(&attr, 0, sizeof(attr));
405 attr.key = ptr_to_u64(key);
406 attr.value = ptr_to_u64(value);
408 return sys_bpf(BPF_MAP_LOOKUP_AND_DELETE_ELEM, &attr, sizeof(attr));
411 int bpf_map_delete_elem(int fd, const void *key)
415 memset(&attr, 0, sizeof(attr));
417 attr.key = ptr_to_u64(key);
419 return sys_bpf(BPF_MAP_DELETE_ELEM, &attr, sizeof(attr));
422 int bpf_map_get_next_key(int fd, const void *key, void *next_key)
426 memset(&attr, 0, sizeof(attr));
428 attr.key = ptr_to_u64(key);
429 attr.next_key = ptr_to_u64(next_key);
431 return sys_bpf(BPF_MAP_GET_NEXT_KEY, &attr, sizeof(attr));
434 int bpf_map_freeze(int fd)
438 memset(&attr, 0, sizeof(attr));
441 return sys_bpf(BPF_MAP_FREEZE, &attr, sizeof(attr));
444 int bpf_obj_pin(int fd, const char *pathname)
448 memset(&attr, 0, sizeof(attr));
449 attr.pathname = ptr_to_u64((void *)pathname);
452 return sys_bpf(BPF_OBJ_PIN, &attr, sizeof(attr));
455 int bpf_obj_get(const char *pathname)
459 memset(&attr, 0, sizeof(attr));
460 attr.pathname = ptr_to_u64((void *)pathname);
462 return sys_bpf(BPF_OBJ_GET, &attr, sizeof(attr));
465 int bpf_prog_attach(int prog_fd, int target_fd, enum bpf_attach_type type,
470 memset(&attr, 0, sizeof(attr));
471 attr.target_fd = target_fd;
472 attr.attach_bpf_fd = prog_fd;
473 attr.attach_type = type;
474 attr.attach_flags = flags;
476 return sys_bpf(BPF_PROG_ATTACH, &attr, sizeof(attr));
479 int bpf_prog_detach(int target_fd, enum bpf_attach_type type)
483 memset(&attr, 0, sizeof(attr));
484 attr.target_fd = target_fd;
485 attr.attach_type = type;
487 return sys_bpf(BPF_PROG_DETACH, &attr, sizeof(attr));
490 int bpf_prog_detach2(int prog_fd, int target_fd, enum bpf_attach_type type)
494 memset(&attr, 0, sizeof(attr));
495 attr.target_fd = target_fd;
496 attr.attach_bpf_fd = prog_fd;
497 attr.attach_type = type;
499 return sys_bpf(BPF_PROG_DETACH, &attr, sizeof(attr));
502 int bpf_prog_query(int target_fd, enum bpf_attach_type type, __u32 query_flags,
503 __u32 *attach_flags, __u32 *prog_ids, __u32 *prog_cnt)
508 memset(&attr, 0, sizeof(attr));
509 attr.query.target_fd = target_fd;
510 attr.query.attach_type = type;
511 attr.query.query_flags = query_flags;
512 attr.query.prog_cnt = *prog_cnt;
513 attr.query.prog_ids = ptr_to_u64(prog_ids);
515 ret = sys_bpf(BPF_PROG_QUERY, &attr, sizeof(attr));
517 *attach_flags = attr.query.attach_flags;
518 *prog_cnt = attr.query.prog_cnt;
522 int bpf_prog_test_run(int prog_fd, int repeat, void *data, __u32 size,
523 void *data_out, __u32 *size_out, __u32 *retval,
529 memset(&attr, 0, sizeof(attr));
530 attr.test.prog_fd = prog_fd;
531 attr.test.data_in = ptr_to_u64(data);
532 attr.test.data_out = ptr_to_u64(data_out);
533 attr.test.data_size_in = size;
534 attr.test.repeat = repeat;
536 ret = sys_bpf(BPF_PROG_TEST_RUN, &attr, sizeof(attr));
538 *size_out = attr.test.data_size_out;
540 *retval = attr.test.retval;
542 *duration = attr.test.duration;
546 int bpf_prog_test_run_xattr(struct bpf_prog_test_run_attr *test_attr)
551 if (!test_attr->data_out && test_attr->data_size_out > 0)
554 memset(&attr, 0, sizeof(attr));
555 attr.test.prog_fd = test_attr->prog_fd;
556 attr.test.data_in = ptr_to_u64(test_attr->data_in);
557 attr.test.data_out = ptr_to_u64(test_attr->data_out);
558 attr.test.data_size_in = test_attr->data_size_in;
559 attr.test.data_size_out = test_attr->data_size_out;
560 attr.test.ctx_in = ptr_to_u64(test_attr->ctx_in);
561 attr.test.ctx_out = ptr_to_u64(test_attr->ctx_out);
562 attr.test.ctx_size_in = test_attr->ctx_size_in;
563 attr.test.ctx_size_out = test_attr->ctx_size_out;
564 attr.test.repeat = test_attr->repeat;
566 ret = sys_bpf(BPF_PROG_TEST_RUN, &attr, sizeof(attr));
567 test_attr->data_size_out = attr.test.data_size_out;
568 test_attr->ctx_size_out = attr.test.ctx_size_out;
569 test_attr->retval = attr.test.retval;
570 test_attr->duration = attr.test.duration;
574 static int bpf_obj_get_next_id(__u32 start_id, __u32 *next_id, int cmd)
579 memset(&attr, 0, sizeof(attr));
580 attr.start_id = start_id;
582 err = sys_bpf(cmd, &attr, sizeof(attr));
584 *next_id = attr.next_id;
589 int bpf_prog_get_next_id(__u32 start_id, __u32 *next_id)
591 return bpf_obj_get_next_id(start_id, next_id, BPF_PROG_GET_NEXT_ID);
594 int bpf_map_get_next_id(__u32 start_id, __u32 *next_id)
596 return bpf_obj_get_next_id(start_id, next_id, BPF_MAP_GET_NEXT_ID);
599 int bpf_btf_get_next_id(__u32 start_id, __u32 *next_id)
601 return bpf_obj_get_next_id(start_id, next_id, BPF_BTF_GET_NEXT_ID);
604 int bpf_prog_get_fd_by_id(__u32 id)
608 memset(&attr, 0, sizeof(attr));
611 return sys_bpf(BPF_PROG_GET_FD_BY_ID, &attr, sizeof(attr));
614 int bpf_map_get_fd_by_id(__u32 id)
618 memset(&attr, 0, sizeof(attr));
621 return sys_bpf(BPF_MAP_GET_FD_BY_ID, &attr, sizeof(attr));
624 int bpf_btf_get_fd_by_id(__u32 id)
628 memset(&attr, 0, sizeof(attr));
631 return sys_bpf(BPF_BTF_GET_FD_BY_ID, &attr, sizeof(attr));
634 int bpf_obj_get_info_by_fd(int prog_fd, void *info, __u32 *info_len)
639 memset(&attr, 0, sizeof(attr));
640 attr.info.bpf_fd = prog_fd;
641 attr.info.info_len = *info_len;
642 attr.info.info = ptr_to_u64(info);
644 err = sys_bpf(BPF_OBJ_GET_INFO_BY_FD, &attr, sizeof(attr));
646 *info_len = attr.info.info_len;
651 int bpf_raw_tracepoint_open(const char *name, int prog_fd)
655 memset(&attr, 0, sizeof(attr));
656 attr.raw_tracepoint.name = ptr_to_u64(name);
657 attr.raw_tracepoint.prog_fd = prog_fd;
659 return sys_bpf(BPF_RAW_TRACEPOINT_OPEN, &attr, sizeof(attr));
662 int bpf_load_btf(void *btf, __u32 btf_size, char *log_buf, __u32 log_buf_size,
665 union bpf_attr attr = {};
668 attr.btf = ptr_to_u64(btf);
669 attr.btf_size = btf_size;
672 if (do_log && log_buf && log_buf_size) {
673 attr.btf_log_level = 1;
674 attr.btf_log_size = log_buf_size;
675 attr.btf_log_buf = ptr_to_u64(log_buf);
678 fd = sys_bpf(BPF_BTF_LOAD, &attr, sizeof(attr));
679 if (fd == -1 && !do_log && log_buf && log_buf_size) {
687 int bpf_task_fd_query(int pid, int fd, __u32 flags, char *buf, __u32 *buf_len,
688 __u32 *prog_id, __u32 *fd_type, __u64 *probe_offset,
691 union bpf_attr attr = {};
694 attr.task_fd_query.pid = pid;
695 attr.task_fd_query.fd = fd;
696 attr.task_fd_query.flags = flags;
697 attr.task_fd_query.buf = ptr_to_u64(buf);
698 attr.task_fd_query.buf_len = *buf_len;
700 err = sys_bpf(BPF_TASK_FD_QUERY, &attr, sizeof(attr));
701 *buf_len = attr.task_fd_query.buf_len;
702 *prog_id = attr.task_fd_query.prog_id;
703 *fd_type = attr.task_fd_query.fd_type;
704 *probe_offset = attr.task_fd_query.probe_offset;
705 *probe_addr = attr.task_fd_query.probe_addr;