1 // SPDX-License-Identifier: LGPL-2.1 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 <memory.h> 26 #include <unistd.h> 27 #include <asm/unistd.h> 28 #include <linux/bpf.h> 29 #include "bpf.h" 30 #include "libbpf.h" 31 #include <errno.h> 32 33 /* 34 * When building perf, unistd.h is overridden. __NR_bpf is 35 * required to be defined explicitly. 36 */ 37 #ifndef __NR_bpf 38 # if defined(__i386__) 39 # define __NR_bpf 357 40 # elif defined(__x86_64__) 41 # define __NR_bpf 321 42 # elif defined(__aarch64__) 43 # define __NR_bpf 280 44 # elif defined(__sparc__) 45 # define __NR_bpf 349 46 # elif defined(__s390__) 47 # define __NR_bpf 351 48 # else 49 # error __NR_bpf not defined. libbpf does not support your arch. 50 # endif 51 #endif 52 53 #ifndef min 54 #define min(x, y) ((x) < (y) ? (x) : (y)) 55 #endif 56 57 static inline __u64 ptr_to_u64(const void *ptr) 58 { 59 return (__u64) (unsigned long) ptr; 60 } 61 62 static inline int sys_bpf(enum bpf_cmd cmd, union bpf_attr *attr, 63 unsigned int size) 64 { 65 return syscall(__NR_bpf, cmd, attr, size); 66 } 67 68 int bpf_create_map_xattr(const struct bpf_create_map_attr *create_attr) 69 { 70 __u32 name_len = create_attr->name ? strlen(create_attr->name) : 0; 71 union bpf_attr attr; 72 73 memset(&attr, '\0', sizeof(attr)); 74 75 attr.map_type = create_attr->map_type; 76 attr.key_size = create_attr->key_size; 77 attr.value_size = create_attr->value_size; 78 attr.max_entries = create_attr->max_entries; 79 attr.map_flags = create_attr->map_flags; 80 memcpy(attr.map_name, create_attr->name, 81 min(name_len, BPF_OBJ_NAME_LEN - 1)); 82 attr.numa_node = create_attr->numa_node; 83 attr.btf_fd = create_attr->btf_fd; 84 attr.btf_key_type_id = create_attr->btf_key_type_id; 85 attr.btf_value_type_id = create_attr->btf_value_type_id; 86 attr.map_ifindex = create_attr->map_ifindex; 87 attr.inner_map_fd = create_attr->inner_map_fd; 88 89 return sys_bpf(BPF_MAP_CREATE, &attr, sizeof(attr)); 90 } 91 92 int bpf_create_map_node(enum bpf_map_type map_type, const char *name, 93 int key_size, int value_size, int max_entries, 94 __u32 map_flags, int node) 95 { 96 struct bpf_create_map_attr map_attr = {}; 97 98 map_attr.name = name; 99 map_attr.map_type = map_type; 100 map_attr.map_flags = map_flags; 101 map_attr.key_size = key_size; 102 map_attr.value_size = value_size; 103 map_attr.max_entries = max_entries; 104 if (node >= 0) { 105 map_attr.numa_node = node; 106 map_attr.map_flags |= BPF_F_NUMA_NODE; 107 } 108 109 return bpf_create_map_xattr(&map_attr); 110 } 111 112 int bpf_create_map(enum bpf_map_type map_type, int key_size, 113 int value_size, int max_entries, __u32 map_flags) 114 { 115 struct bpf_create_map_attr map_attr = {}; 116 117 map_attr.map_type = map_type; 118 map_attr.map_flags = map_flags; 119 map_attr.key_size = key_size; 120 map_attr.value_size = value_size; 121 map_attr.max_entries = max_entries; 122 123 return bpf_create_map_xattr(&map_attr); 124 } 125 126 int bpf_create_map_name(enum bpf_map_type map_type, const char *name, 127 int key_size, int value_size, int max_entries, 128 __u32 map_flags) 129 { 130 struct bpf_create_map_attr map_attr = {}; 131 132 map_attr.name = name; 133 map_attr.map_type = map_type; 134 map_attr.map_flags = map_flags; 135 map_attr.key_size = key_size; 136 map_attr.value_size = value_size; 137 map_attr.max_entries = max_entries; 138 139 return bpf_create_map_xattr(&map_attr); 140 } 141 142 int bpf_create_map_in_map_node(enum bpf_map_type map_type, const char *name, 143 int key_size, int inner_map_fd, int max_entries, 144 __u32 map_flags, int node) 145 { 146 __u32 name_len = name ? strlen(name) : 0; 147 union bpf_attr attr; 148 149 memset(&attr, '\0', sizeof(attr)); 150 151 attr.map_type = map_type; 152 attr.key_size = key_size; 153 attr.value_size = 4; 154 attr.inner_map_fd = inner_map_fd; 155 attr.max_entries = max_entries; 156 attr.map_flags = map_flags; 157 memcpy(attr.map_name, name, min(name_len, BPF_OBJ_NAME_LEN - 1)); 158 159 if (node >= 0) { 160 attr.map_flags |= BPF_F_NUMA_NODE; 161 attr.numa_node = node; 162 } 163 164 return sys_bpf(BPF_MAP_CREATE, &attr, sizeof(attr)); 165 } 166 167 int bpf_create_map_in_map(enum bpf_map_type map_type, const char *name, 168 int key_size, int inner_map_fd, int max_entries, 169 __u32 map_flags) 170 { 171 return bpf_create_map_in_map_node(map_type, name, key_size, 172 inner_map_fd, max_entries, map_flags, 173 -1); 174 } 175 176 int bpf_load_program_xattr(const struct bpf_load_program_attr *load_attr, 177 char *log_buf, size_t log_buf_sz) 178 { 179 union bpf_attr attr; 180 __u32 name_len; 181 int fd; 182 183 if (!load_attr) 184 return -EINVAL; 185 186 name_len = load_attr->name ? strlen(load_attr->name) : 0; 187 188 bzero(&attr, sizeof(attr)); 189 attr.prog_type = load_attr->prog_type; 190 attr.expected_attach_type = load_attr->expected_attach_type; 191 attr.insn_cnt = (__u32)load_attr->insns_cnt; 192 attr.insns = ptr_to_u64(load_attr->insns); 193 attr.license = ptr_to_u64(load_attr->license); 194 attr.log_buf = ptr_to_u64(NULL); 195 attr.log_size = 0; 196 attr.log_level = 0; 197 attr.kern_version = load_attr->kern_version; 198 attr.prog_ifindex = load_attr->prog_ifindex; 199 memcpy(attr.prog_name, load_attr->name, 200 min(name_len, BPF_OBJ_NAME_LEN - 1)); 201 202 fd = sys_bpf(BPF_PROG_LOAD, &attr, sizeof(attr)); 203 if (fd >= 0 || !log_buf || !log_buf_sz) 204 return fd; 205 206 /* Try again with log */ 207 attr.log_buf = ptr_to_u64(log_buf); 208 attr.log_size = log_buf_sz; 209 attr.log_level = 1; 210 log_buf[0] = 0; 211 return sys_bpf(BPF_PROG_LOAD, &attr, sizeof(attr)); 212 } 213 214 int bpf_load_program(enum bpf_prog_type type, const struct bpf_insn *insns, 215 size_t insns_cnt, const char *license, 216 __u32 kern_version, char *log_buf, 217 size_t log_buf_sz) 218 { 219 struct bpf_load_program_attr load_attr; 220 221 memset(&load_attr, 0, sizeof(struct bpf_load_program_attr)); 222 load_attr.prog_type = type; 223 load_attr.expected_attach_type = 0; 224 load_attr.name = NULL; 225 load_attr.insns = insns; 226 load_attr.insns_cnt = insns_cnt; 227 load_attr.license = license; 228 load_attr.kern_version = kern_version; 229 230 return bpf_load_program_xattr(&load_attr, log_buf, log_buf_sz); 231 } 232 233 int bpf_verify_program(enum bpf_prog_type type, const struct bpf_insn *insns, 234 size_t insns_cnt, int strict_alignment, 235 const char *license, __u32 kern_version, 236 char *log_buf, size_t log_buf_sz, int log_level) 237 { 238 union bpf_attr attr; 239 240 bzero(&attr, sizeof(attr)); 241 attr.prog_type = type; 242 attr.insn_cnt = (__u32)insns_cnt; 243 attr.insns = ptr_to_u64(insns); 244 attr.license = ptr_to_u64(license); 245 attr.log_buf = ptr_to_u64(log_buf); 246 attr.log_size = log_buf_sz; 247 attr.log_level = log_level; 248 log_buf[0] = 0; 249 attr.kern_version = kern_version; 250 attr.prog_flags = strict_alignment ? BPF_F_STRICT_ALIGNMENT : 0; 251 252 return sys_bpf(BPF_PROG_LOAD, &attr, sizeof(attr)); 253 } 254 255 int bpf_map_update_elem(int fd, const void *key, const void *value, 256 __u64 flags) 257 { 258 union bpf_attr attr; 259 260 bzero(&attr, sizeof(attr)); 261 attr.map_fd = fd; 262 attr.key = ptr_to_u64(key); 263 attr.value = ptr_to_u64(value); 264 attr.flags = flags; 265 266 return sys_bpf(BPF_MAP_UPDATE_ELEM, &attr, sizeof(attr)); 267 } 268 269 int bpf_map_lookup_elem(int fd, const void *key, void *value) 270 { 271 union bpf_attr attr; 272 273 bzero(&attr, sizeof(attr)); 274 attr.map_fd = fd; 275 attr.key = ptr_to_u64(key); 276 attr.value = ptr_to_u64(value); 277 278 return sys_bpf(BPF_MAP_LOOKUP_ELEM, &attr, sizeof(attr)); 279 } 280 281 int bpf_map_delete_elem(int fd, const void *key) 282 { 283 union bpf_attr attr; 284 285 bzero(&attr, sizeof(attr)); 286 attr.map_fd = fd; 287 attr.key = ptr_to_u64(key); 288 289 return sys_bpf(BPF_MAP_DELETE_ELEM, &attr, sizeof(attr)); 290 } 291 292 int bpf_map_get_next_key(int fd, const void *key, void *next_key) 293 { 294 union bpf_attr attr; 295 296 bzero(&attr, sizeof(attr)); 297 attr.map_fd = fd; 298 attr.key = ptr_to_u64(key); 299 attr.next_key = ptr_to_u64(next_key); 300 301 return sys_bpf(BPF_MAP_GET_NEXT_KEY, &attr, sizeof(attr)); 302 } 303 304 int bpf_obj_pin(int fd, const char *pathname) 305 { 306 union bpf_attr attr; 307 308 bzero(&attr, sizeof(attr)); 309 attr.pathname = ptr_to_u64((void *)pathname); 310 attr.bpf_fd = fd; 311 312 return sys_bpf(BPF_OBJ_PIN, &attr, sizeof(attr)); 313 } 314 315 int bpf_obj_get(const char *pathname) 316 { 317 union bpf_attr attr; 318 319 bzero(&attr, sizeof(attr)); 320 attr.pathname = ptr_to_u64((void *)pathname); 321 322 return sys_bpf(BPF_OBJ_GET, &attr, sizeof(attr)); 323 } 324 325 int bpf_prog_attach(int prog_fd, int target_fd, enum bpf_attach_type type, 326 unsigned int flags) 327 { 328 union bpf_attr attr; 329 330 bzero(&attr, sizeof(attr)); 331 attr.target_fd = target_fd; 332 attr.attach_bpf_fd = prog_fd; 333 attr.attach_type = type; 334 attr.attach_flags = flags; 335 336 return sys_bpf(BPF_PROG_ATTACH, &attr, sizeof(attr)); 337 } 338 339 int bpf_prog_detach(int target_fd, enum bpf_attach_type type) 340 { 341 union bpf_attr attr; 342 343 bzero(&attr, sizeof(attr)); 344 attr.target_fd = target_fd; 345 attr.attach_type = type; 346 347 return sys_bpf(BPF_PROG_DETACH, &attr, sizeof(attr)); 348 } 349 350 int bpf_prog_detach2(int prog_fd, int target_fd, enum bpf_attach_type type) 351 { 352 union bpf_attr attr; 353 354 bzero(&attr, sizeof(attr)); 355 attr.target_fd = target_fd; 356 attr.attach_bpf_fd = prog_fd; 357 attr.attach_type = type; 358 359 return sys_bpf(BPF_PROG_DETACH, &attr, sizeof(attr)); 360 } 361 362 int bpf_prog_query(int target_fd, enum bpf_attach_type type, __u32 query_flags, 363 __u32 *attach_flags, __u32 *prog_ids, __u32 *prog_cnt) 364 { 365 union bpf_attr attr; 366 int ret; 367 368 bzero(&attr, sizeof(attr)); 369 attr.query.target_fd = target_fd; 370 attr.query.attach_type = type; 371 attr.query.query_flags = query_flags; 372 attr.query.prog_cnt = *prog_cnt; 373 attr.query.prog_ids = ptr_to_u64(prog_ids); 374 375 ret = sys_bpf(BPF_PROG_QUERY, &attr, sizeof(attr)); 376 if (attach_flags) 377 *attach_flags = attr.query.attach_flags; 378 *prog_cnt = attr.query.prog_cnt; 379 return ret; 380 } 381 382 int bpf_prog_test_run(int prog_fd, int repeat, void *data, __u32 size, 383 void *data_out, __u32 *size_out, __u32 *retval, 384 __u32 *duration) 385 { 386 union bpf_attr attr; 387 int ret; 388 389 bzero(&attr, sizeof(attr)); 390 attr.test.prog_fd = prog_fd; 391 attr.test.data_in = ptr_to_u64(data); 392 attr.test.data_out = ptr_to_u64(data_out); 393 attr.test.data_size_in = size; 394 attr.test.repeat = repeat; 395 396 ret = sys_bpf(BPF_PROG_TEST_RUN, &attr, sizeof(attr)); 397 if (size_out) 398 *size_out = attr.test.data_size_out; 399 if (retval) 400 *retval = attr.test.retval; 401 if (duration) 402 *duration = attr.test.duration; 403 return ret; 404 } 405 406 int bpf_prog_get_next_id(__u32 start_id, __u32 *next_id) 407 { 408 union bpf_attr attr; 409 int err; 410 411 bzero(&attr, sizeof(attr)); 412 attr.start_id = start_id; 413 414 err = sys_bpf(BPF_PROG_GET_NEXT_ID, &attr, sizeof(attr)); 415 if (!err) 416 *next_id = attr.next_id; 417 418 return err; 419 } 420 421 int bpf_map_get_next_id(__u32 start_id, __u32 *next_id) 422 { 423 union bpf_attr attr; 424 int err; 425 426 bzero(&attr, sizeof(attr)); 427 attr.start_id = start_id; 428 429 err = sys_bpf(BPF_MAP_GET_NEXT_ID, &attr, sizeof(attr)); 430 if (!err) 431 *next_id = attr.next_id; 432 433 return err; 434 } 435 436 int bpf_prog_get_fd_by_id(__u32 id) 437 { 438 union bpf_attr attr; 439 440 bzero(&attr, sizeof(attr)); 441 attr.prog_id = id; 442 443 return sys_bpf(BPF_PROG_GET_FD_BY_ID, &attr, sizeof(attr)); 444 } 445 446 int bpf_map_get_fd_by_id(__u32 id) 447 { 448 union bpf_attr attr; 449 450 bzero(&attr, sizeof(attr)); 451 attr.map_id = id; 452 453 return sys_bpf(BPF_MAP_GET_FD_BY_ID, &attr, sizeof(attr)); 454 } 455 456 int bpf_btf_get_fd_by_id(__u32 id) 457 { 458 union bpf_attr attr; 459 460 bzero(&attr, sizeof(attr)); 461 attr.btf_id = id; 462 463 return sys_bpf(BPF_BTF_GET_FD_BY_ID, &attr, sizeof(attr)); 464 } 465 466 int bpf_obj_get_info_by_fd(int prog_fd, void *info, __u32 *info_len) 467 { 468 union bpf_attr attr; 469 int err; 470 471 bzero(&attr, sizeof(attr)); 472 attr.info.bpf_fd = prog_fd; 473 attr.info.info_len = *info_len; 474 attr.info.info = ptr_to_u64(info); 475 476 err = sys_bpf(BPF_OBJ_GET_INFO_BY_FD, &attr, sizeof(attr)); 477 if (!err) 478 *info_len = attr.info.info_len; 479 480 return err; 481 } 482 483 int bpf_raw_tracepoint_open(const char *name, int prog_fd) 484 { 485 union bpf_attr attr; 486 487 bzero(&attr, sizeof(attr)); 488 attr.raw_tracepoint.name = ptr_to_u64(name); 489 attr.raw_tracepoint.prog_fd = prog_fd; 490 491 return sys_bpf(BPF_RAW_TRACEPOINT_OPEN, &attr, sizeof(attr)); 492 } 493 494 int bpf_load_btf(void *btf, __u32 btf_size, char *log_buf, __u32 log_buf_size, 495 bool do_log) 496 { 497 union bpf_attr attr = {}; 498 int fd; 499 500 attr.btf = ptr_to_u64(btf); 501 attr.btf_size = btf_size; 502 503 retry: 504 if (do_log && log_buf && log_buf_size) { 505 attr.btf_log_level = 1; 506 attr.btf_log_size = log_buf_size; 507 attr.btf_log_buf = ptr_to_u64(log_buf); 508 } 509 510 fd = sys_bpf(BPF_BTF_LOAD, &attr, sizeof(attr)); 511 if (fd == -1 && !do_log && log_buf && log_buf_size) { 512 do_log = true; 513 goto retry; 514 } 515 516 return fd; 517 } 518 519 int bpf_task_fd_query(int pid, int fd, __u32 flags, char *buf, __u32 *buf_len, 520 __u32 *prog_id, __u32 *fd_type, __u64 *probe_offset, 521 __u64 *probe_addr) 522 { 523 union bpf_attr attr = {}; 524 int err; 525 526 attr.task_fd_query.pid = pid; 527 attr.task_fd_query.fd = fd; 528 attr.task_fd_query.flags = flags; 529 attr.task_fd_query.buf = ptr_to_u64(buf); 530 attr.task_fd_query.buf_len = *buf_len; 531 532 err = sys_bpf(BPF_TASK_FD_QUERY, &attr, sizeof(attr)); 533 *buf_len = attr.task_fd_query.buf_len; 534 *prog_id = attr.task_fd_query.prog_id; 535 *fd_type = attr.task_fd_query.fd_type; 536 *probe_offset = attr.task_fd_query.probe_offset; 537 *probe_addr = attr.task_fd_query.probe_addr; 538 539 return err; 540 } 541