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>
27 #include <asm/unistd.h>
28 #include <linux/bpf.h>
34 * When building perf, unistd.h is overridden. __NR_bpf is
35 * required to be defined explicitly.
38 # if defined(__i386__)
40 # elif defined(__x86_64__)
42 # elif defined(__aarch64__)
44 # elif defined(__sparc__)
46 # elif defined(__s390__)
49 # error __NR_bpf not defined. libbpf does not support your arch.
54 #define min(x, y) ((x) < (y) ? (x) : (y))
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)
81 __u32 name_len = create_attr->name ? strlen(create_attr->name) : 0;
84 memset(&attr, '\0', sizeof(attr));
86 attr.map_type = create_attr->map_type;
87 attr.key_size = create_attr->key_size;
88 attr.value_size = create_attr->value_size;
89 attr.max_entries = create_attr->max_entries;
90 attr.map_flags = create_attr->map_flags;
91 memcpy(attr.map_name, create_attr->name,
92 min(name_len, 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)
157 __u32 name_len = name ? strlen(name) : 0;
160 memset(&attr, '\0', sizeof(attr));
162 attr.map_type = map_type;
163 attr.key_size = key_size;
165 attr.inner_map_fd = inner_map_fd;
166 attr.max_entries = max_entries;
167 attr.map_flags = map_flags;
168 memcpy(attr.map_name, name, min(name_len, BPF_OBJ_NAME_LEN - 1));
171 attr.map_flags |= BPF_F_NUMA_NODE;
172 attr.numa_node = node;
175 return sys_bpf(BPF_MAP_CREATE, &attr, sizeof(attr));
178 int bpf_create_map_in_map(enum bpf_map_type map_type, const char *name,
179 int key_size, int inner_map_fd, int max_entries,
182 return bpf_create_map_in_map_node(map_type, name, key_size,
183 inner_map_fd, max_entries, map_flags,
188 alloc_zero_tailing_info(const void *orecord, __u32 cnt,
189 __u32 actual_rec_size, __u32 expected_rec_size)
191 __u64 info_len = actual_rec_size * cnt;
192 void *info, *nrecord;
195 info = malloc(info_len);
199 /* zero out bytes kernel does not understand */
201 for (i = 0; i < cnt; i++) {
202 memcpy(nrecord, orecord, expected_rec_size);
203 memset(nrecord + expected_rec_size, 0,
204 actual_rec_size - expected_rec_size);
205 orecord += actual_rec_size;
206 nrecord += actual_rec_size;
212 int bpf_load_program_xattr(const struct bpf_load_program_attr *load_attr,
213 char *log_buf, size_t log_buf_sz)
215 void *finfo = NULL, *linfo = NULL;
223 name_len = load_attr->name ? strlen(load_attr->name) : 0;
225 bzero(&attr, sizeof(attr));
226 attr.prog_type = load_attr->prog_type;
227 attr.expected_attach_type = load_attr->expected_attach_type;
228 attr.insn_cnt = (__u32)load_attr->insns_cnt;
229 attr.insns = ptr_to_u64(load_attr->insns);
230 attr.license = ptr_to_u64(load_attr->license);
231 attr.log_buf = ptr_to_u64(NULL);
234 attr.kern_version = load_attr->kern_version;
235 attr.prog_ifindex = load_attr->prog_ifindex;
236 attr.prog_btf_fd = load_attr->prog_btf_fd;
237 attr.func_info_rec_size = load_attr->func_info_rec_size;
238 attr.func_info_cnt = load_attr->func_info_cnt;
239 attr.func_info = ptr_to_u64(load_attr->func_info);
240 attr.line_info_rec_size = load_attr->line_info_rec_size;
241 attr.line_info_cnt = load_attr->line_info_cnt;
242 attr.line_info = ptr_to_u64(load_attr->line_info);
243 memcpy(attr.prog_name, load_attr->name,
244 min(name_len, BPF_OBJ_NAME_LEN - 1));
246 fd = sys_bpf_prog_load(&attr, sizeof(attr));
250 /* After bpf_prog_load, the kernel may modify certain attributes
251 * to give user space a hint how to deal with loading failure.
252 * Check to see whether we can make some changes and load again.
254 while (errno == E2BIG && (!finfo || !linfo)) {
255 if (!finfo && attr.func_info_cnt &&
256 attr.func_info_rec_size < load_attr->func_info_rec_size) {
257 /* try with corrected func info records */
258 finfo = alloc_zero_tailing_info(load_attr->func_info,
259 load_attr->func_info_cnt,
260 load_attr->func_info_rec_size,
261 attr.func_info_rec_size);
265 attr.func_info = ptr_to_u64(finfo);
266 attr.func_info_rec_size = load_attr->func_info_rec_size;
267 } else if (!linfo && attr.line_info_cnt &&
268 attr.line_info_rec_size <
269 load_attr->line_info_rec_size) {
270 linfo = alloc_zero_tailing_info(load_attr->line_info,
271 load_attr->line_info_cnt,
272 load_attr->line_info_rec_size,
273 attr.line_info_rec_size);
277 attr.line_info = ptr_to_u64(linfo);
278 attr.line_info_rec_size = load_attr->line_info_rec_size;
283 fd = sys_bpf_prog_load(&attr, sizeof(attr));
289 if (!log_buf || !log_buf_sz)
292 /* Try again with log */
293 attr.log_buf = ptr_to_u64(log_buf);
294 attr.log_size = log_buf_sz;
297 fd = sys_bpf_prog_load(&attr, sizeof(attr));
304 int bpf_load_program(enum bpf_prog_type type, const struct bpf_insn *insns,
305 size_t insns_cnt, const char *license,
306 __u32 kern_version, char *log_buf,
309 struct bpf_load_program_attr load_attr;
311 memset(&load_attr, 0, sizeof(struct bpf_load_program_attr));
312 load_attr.prog_type = type;
313 load_attr.expected_attach_type = 0;
314 load_attr.name = NULL;
315 load_attr.insns = insns;
316 load_attr.insns_cnt = insns_cnt;
317 load_attr.license = license;
318 load_attr.kern_version = kern_version;
320 return bpf_load_program_xattr(&load_attr, log_buf, log_buf_sz);
323 int bpf_verify_program(enum bpf_prog_type type, const struct bpf_insn *insns,
324 size_t insns_cnt, __u32 prog_flags, const char *license,
325 __u32 kern_version, char *log_buf, size_t log_buf_sz,
330 bzero(&attr, sizeof(attr));
331 attr.prog_type = type;
332 attr.insn_cnt = (__u32)insns_cnt;
333 attr.insns = ptr_to_u64(insns);
334 attr.license = ptr_to_u64(license);
335 attr.log_buf = ptr_to_u64(log_buf);
336 attr.log_size = log_buf_sz;
337 attr.log_level = log_level;
339 attr.kern_version = kern_version;
340 attr.prog_flags = prog_flags;
342 return sys_bpf_prog_load(&attr, sizeof(attr));
345 int bpf_map_update_elem(int fd, const void *key, const void *value,
350 bzero(&attr, sizeof(attr));
352 attr.key = ptr_to_u64(key);
353 attr.value = ptr_to_u64(value);
356 return sys_bpf(BPF_MAP_UPDATE_ELEM, &attr, sizeof(attr));
359 int bpf_map_lookup_elem(int fd, const void *key, void *value)
363 bzero(&attr, sizeof(attr));
365 attr.key = ptr_to_u64(key);
366 attr.value = ptr_to_u64(value);
368 return sys_bpf(BPF_MAP_LOOKUP_ELEM, &attr, sizeof(attr));
371 int bpf_map_lookup_and_delete_elem(int fd, const void *key, void *value)
375 bzero(&attr, sizeof(attr));
377 attr.key = ptr_to_u64(key);
378 attr.value = ptr_to_u64(value);
380 return sys_bpf(BPF_MAP_LOOKUP_AND_DELETE_ELEM, &attr, sizeof(attr));
383 int bpf_map_delete_elem(int fd, const void *key)
387 bzero(&attr, sizeof(attr));
389 attr.key = ptr_to_u64(key);
391 return sys_bpf(BPF_MAP_DELETE_ELEM, &attr, sizeof(attr));
394 int bpf_map_get_next_key(int fd, const void *key, void *next_key)
398 bzero(&attr, sizeof(attr));
400 attr.key = ptr_to_u64(key);
401 attr.next_key = ptr_to_u64(next_key);
403 return sys_bpf(BPF_MAP_GET_NEXT_KEY, &attr, sizeof(attr));
406 int bpf_obj_pin(int fd, const char *pathname)
410 bzero(&attr, sizeof(attr));
411 attr.pathname = ptr_to_u64((void *)pathname);
414 return sys_bpf(BPF_OBJ_PIN, &attr, sizeof(attr));
417 int bpf_obj_get(const char *pathname)
421 bzero(&attr, sizeof(attr));
422 attr.pathname = ptr_to_u64((void *)pathname);
424 return sys_bpf(BPF_OBJ_GET, &attr, sizeof(attr));
427 int bpf_prog_attach(int prog_fd, int target_fd, enum bpf_attach_type type,
432 bzero(&attr, sizeof(attr));
433 attr.target_fd = target_fd;
434 attr.attach_bpf_fd = prog_fd;
435 attr.attach_type = type;
436 attr.attach_flags = flags;
438 return sys_bpf(BPF_PROG_ATTACH, &attr, sizeof(attr));
441 int bpf_prog_detach(int target_fd, enum bpf_attach_type type)
445 bzero(&attr, sizeof(attr));
446 attr.target_fd = target_fd;
447 attr.attach_type = type;
449 return sys_bpf(BPF_PROG_DETACH, &attr, sizeof(attr));
452 int bpf_prog_detach2(int prog_fd, int target_fd, enum bpf_attach_type type)
456 bzero(&attr, sizeof(attr));
457 attr.target_fd = target_fd;
458 attr.attach_bpf_fd = prog_fd;
459 attr.attach_type = type;
461 return sys_bpf(BPF_PROG_DETACH, &attr, sizeof(attr));
464 int bpf_prog_query(int target_fd, enum bpf_attach_type type, __u32 query_flags,
465 __u32 *attach_flags, __u32 *prog_ids, __u32 *prog_cnt)
470 bzero(&attr, sizeof(attr));
471 attr.query.target_fd = target_fd;
472 attr.query.attach_type = type;
473 attr.query.query_flags = query_flags;
474 attr.query.prog_cnt = *prog_cnt;
475 attr.query.prog_ids = ptr_to_u64(prog_ids);
477 ret = sys_bpf(BPF_PROG_QUERY, &attr, sizeof(attr));
479 *attach_flags = attr.query.attach_flags;
480 *prog_cnt = attr.query.prog_cnt;
484 int bpf_prog_test_run(int prog_fd, int repeat, void *data, __u32 size,
485 void *data_out, __u32 *size_out, __u32 *retval,
491 bzero(&attr, sizeof(attr));
492 attr.test.prog_fd = prog_fd;
493 attr.test.data_in = ptr_to_u64(data);
494 attr.test.data_out = ptr_to_u64(data_out);
495 attr.test.data_size_in = size;
496 attr.test.repeat = repeat;
498 ret = sys_bpf(BPF_PROG_TEST_RUN, &attr, sizeof(attr));
500 *size_out = attr.test.data_size_out;
502 *retval = attr.test.retval;
504 *duration = attr.test.duration;
508 int bpf_prog_test_run_xattr(struct bpf_prog_test_run_attr *test_attr)
513 if (!test_attr->data_out && test_attr->data_size_out > 0)
516 bzero(&attr, sizeof(attr));
517 attr.test.prog_fd = test_attr->prog_fd;
518 attr.test.data_in = ptr_to_u64(test_attr->data_in);
519 attr.test.data_out = ptr_to_u64(test_attr->data_out);
520 attr.test.data_size_in = test_attr->data_size_in;
521 attr.test.data_size_out = test_attr->data_size_out;
522 attr.test.repeat = test_attr->repeat;
524 ret = sys_bpf(BPF_PROG_TEST_RUN, &attr, sizeof(attr));
525 test_attr->data_size_out = attr.test.data_size_out;
526 test_attr->retval = attr.test.retval;
527 test_attr->duration = attr.test.duration;
531 int bpf_prog_get_next_id(__u32 start_id, __u32 *next_id)
536 bzero(&attr, sizeof(attr));
537 attr.start_id = start_id;
539 err = sys_bpf(BPF_PROG_GET_NEXT_ID, &attr, sizeof(attr));
541 *next_id = attr.next_id;
546 int bpf_map_get_next_id(__u32 start_id, __u32 *next_id)
551 bzero(&attr, sizeof(attr));
552 attr.start_id = start_id;
554 err = sys_bpf(BPF_MAP_GET_NEXT_ID, &attr, sizeof(attr));
556 *next_id = attr.next_id;
561 int bpf_prog_get_fd_by_id(__u32 id)
565 bzero(&attr, sizeof(attr));
568 return sys_bpf(BPF_PROG_GET_FD_BY_ID, &attr, sizeof(attr));
571 int bpf_map_get_fd_by_id(__u32 id)
575 bzero(&attr, sizeof(attr));
578 return sys_bpf(BPF_MAP_GET_FD_BY_ID, &attr, sizeof(attr));
581 int bpf_btf_get_fd_by_id(__u32 id)
585 bzero(&attr, sizeof(attr));
588 return sys_bpf(BPF_BTF_GET_FD_BY_ID, &attr, sizeof(attr));
591 int bpf_obj_get_info_by_fd(int prog_fd, void *info, __u32 *info_len)
596 bzero(&attr, sizeof(attr));
597 attr.info.bpf_fd = prog_fd;
598 attr.info.info_len = *info_len;
599 attr.info.info = ptr_to_u64(info);
601 err = sys_bpf(BPF_OBJ_GET_INFO_BY_FD, &attr, sizeof(attr));
603 *info_len = attr.info.info_len;
608 int bpf_raw_tracepoint_open(const char *name, int prog_fd)
612 bzero(&attr, sizeof(attr));
613 attr.raw_tracepoint.name = ptr_to_u64(name);
614 attr.raw_tracepoint.prog_fd = prog_fd;
616 return sys_bpf(BPF_RAW_TRACEPOINT_OPEN, &attr, sizeof(attr));
619 int bpf_load_btf(void *btf, __u32 btf_size, char *log_buf, __u32 log_buf_size,
622 union bpf_attr attr = {};
625 attr.btf = ptr_to_u64(btf);
626 attr.btf_size = btf_size;
629 if (do_log && log_buf && log_buf_size) {
630 attr.btf_log_level = 1;
631 attr.btf_log_size = log_buf_size;
632 attr.btf_log_buf = ptr_to_u64(log_buf);
635 fd = sys_bpf(BPF_BTF_LOAD, &attr, sizeof(attr));
636 if (fd == -1 && !do_log && log_buf && log_buf_size) {
644 int bpf_task_fd_query(int pid, int fd, __u32 flags, char *buf, __u32 *buf_len,
645 __u32 *prog_id, __u32 *fd_type, __u64 *probe_offset,
648 union bpf_attr attr = {};
651 attr.task_fd_query.pid = pid;
652 attr.task_fd_query.fd = fd;
653 attr.task_fd_query.flags = flags;
654 attr.task_fd_query.buf = ptr_to_u64(buf);
655 attr.task_fd_query.buf_len = *buf_len;
657 err = sys_bpf(BPF_TASK_FD_QUERY, &attr, sizeof(attr));
658 *buf_len = attr.task_fd_query.buf_len;
659 *prog_id = attr.task_fd_query.prog_id;
660 *fd_type = attr.task_fd_query.fd_type;
661 *probe_offset = attr.task_fd_query.probe_offset;
662 *probe_addr = attr.task_fd_query.probe_addr;