1 /* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */ 2 3 /* 4 * Common eBPF ELF object loading 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 #ifndef __LIBBPF_LIBBPF_H 11 #define __LIBBPF_LIBBPF_H 12 13 #include <stdarg.h> 14 #include <stdio.h> 15 #include <stdint.h> 16 #include <stdbool.h> 17 #include <sys/types.h> // for size_t 18 #include <linux/bpf.h> 19 20 #include "libbpf_common.h" 21 #include "libbpf_legacy.h" 22 23 #ifdef __cplusplus 24 extern "C" { 25 #endif 26 27 LIBBPF_API __u32 libbpf_major_version(void); 28 LIBBPF_API __u32 libbpf_minor_version(void); 29 LIBBPF_API const char *libbpf_version_string(void); 30 31 enum libbpf_errno { 32 __LIBBPF_ERRNO__START = 4000, 33 34 /* Something wrong in libelf */ 35 LIBBPF_ERRNO__LIBELF = __LIBBPF_ERRNO__START, 36 LIBBPF_ERRNO__FORMAT, /* BPF object format invalid */ 37 LIBBPF_ERRNO__KVERSION, /* Incorrect or no 'version' section */ 38 LIBBPF_ERRNO__ENDIAN, /* Endian mismatch */ 39 LIBBPF_ERRNO__INTERNAL, /* Internal error in libbpf */ 40 LIBBPF_ERRNO__RELOC, /* Relocation failed */ 41 LIBBPF_ERRNO__LOAD, /* Load program failure for unknown reason */ 42 LIBBPF_ERRNO__VERIFY, /* Kernel verifier blocks program loading */ 43 LIBBPF_ERRNO__PROG2BIG, /* Program too big */ 44 LIBBPF_ERRNO__KVER, /* Incorrect kernel version */ 45 LIBBPF_ERRNO__PROGTYPE, /* Kernel doesn't support this program type */ 46 LIBBPF_ERRNO__WRNGPID, /* Wrong pid in netlink message */ 47 LIBBPF_ERRNO__INVSEQ, /* Invalid netlink sequence */ 48 LIBBPF_ERRNO__NLPARSE, /* netlink parsing error */ 49 __LIBBPF_ERRNO__END, 50 }; 51 52 LIBBPF_API int libbpf_strerror(int err, char *buf, size_t size); 53 54 /** 55 * @brief **libbpf_bpf_attach_type_str()** converts the provided attach type 56 * value into a textual representation. 57 * @param t The attach type. 58 * @return Pointer to a static string identifying the attach type. NULL is 59 * returned for unknown **bpf_attach_type** values. 60 */ 61 LIBBPF_API const char *libbpf_bpf_attach_type_str(enum bpf_attach_type t); 62 63 /** 64 * @brief **libbpf_bpf_link_type_str()** converts the provided link type value 65 * into a textual representation. 66 * @param t The link type. 67 * @return Pointer to a static string identifying the link type. NULL is 68 * returned for unknown **bpf_link_type** values. 69 */ 70 LIBBPF_API const char *libbpf_bpf_link_type_str(enum bpf_link_type t); 71 72 /** 73 * @brief **libbpf_bpf_map_type_str()** converts the provided map type value 74 * into a textual representation. 75 * @param t The map type. 76 * @return Pointer to a static string identifying the map type. NULL is 77 * returned for unknown **bpf_map_type** values. 78 */ 79 LIBBPF_API const char *libbpf_bpf_map_type_str(enum bpf_map_type t); 80 81 /** 82 * @brief **libbpf_bpf_prog_type_str()** converts the provided program type 83 * value into a textual representation. 84 * @param t The program type. 85 * @return Pointer to a static string identifying the program type. NULL is 86 * returned for unknown **bpf_prog_type** values. 87 */ 88 LIBBPF_API const char *libbpf_bpf_prog_type_str(enum bpf_prog_type t); 89 90 enum libbpf_print_level { 91 LIBBPF_WARN, 92 LIBBPF_INFO, 93 LIBBPF_DEBUG, 94 }; 95 96 typedef int (*libbpf_print_fn_t)(enum libbpf_print_level level, 97 const char *, va_list ap); 98 99 /** 100 * @brief **libbpf_set_print()** sets user-provided log callback function to 101 * be used for libbpf warnings and informational messages. If the user callback 102 * is not set, messages are logged to stderr by default. The verbosity of these 103 * messages can be controlled by setting the environment variable 104 * LIBBPF_LOG_LEVEL to either warn, info, or debug. 105 * @param fn The log print function. If NULL, libbpf won't print anything. 106 * @return Pointer to old print function. 107 * 108 * This function is thread-safe. 109 */ 110 LIBBPF_API libbpf_print_fn_t libbpf_set_print(libbpf_print_fn_t fn); 111 112 /* Hide internal to user */ 113 struct bpf_object; 114 115 struct bpf_object_open_opts { 116 /* size of this struct, for forward/backward compatibility */ 117 size_t sz; 118 /* object name override, if provided: 119 * - for object open from file, this will override setting object 120 * name from file path's base name; 121 * - for object open from memory buffer, this will specify an object 122 * name and will override default "<addr>-<buf-size>" name; 123 */ 124 const char *object_name; 125 /* parse map definitions non-strictly, allowing extra attributes/data */ 126 bool relaxed_maps; 127 /* maps that set the 'pinning' attribute in their definition will have 128 * their pin_path attribute set to a file in this directory, and be 129 * auto-pinned to that path on load; defaults to "/sys/fs/bpf". 130 */ 131 const char *pin_root_path; 132 133 __u32 :32; /* stub out now removed attach_prog_fd */ 134 135 /* Additional kernel config content that augments and overrides 136 * system Kconfig for CONFIG_xxx externs. 137 */ 138 const char *kconfig; 139 /* Path to the custom BTF to be used for BPF CO-RE relocations. 140 * This custom BTF completely replaces the use of vmlinux BTF 141 * for the purpose of CO-RE relocations. 142 * NOTE: any other BPF feature (e.g., fentry/fexit programs, 143 * struct_ops, etc) will need actual kernel BTF at /sys/kernel/btf/vmlinux. 144 */ 145 const char *btf_custom_path; 146 /* Pointer to a buffer for storing kernel logs for applicable BPF 147 * commands. Valid kernel_log_size has to be specified as well and are 148 * passed-through to bpf() syscall. Keep in mind that kernel might 149 * fail operation with -ENOSPC error if provided buffer is too small 150 * to contain entire log output. 151 * See the comment below for kernel_log_level for interaction between 152 * log_buf and log_level settings. 153 * 154 * If specified, this log buffer will be passed for: 155 * - each BPF progral load (BPF_PROG_LOAD) attempt, unless overridden 156 * with bpf_program__set_log() on per-program level, to get 157 * BPF verifier log output. 158 * - during BPF object's BTF load into kernel (BPF_BTF_LOAD) to get 159 * BTF sanity checking log. 160 * 161 * Each BPF command (BPF_BTF_LOAD or BPF_PROG_LOAD) will overwrite 162 * previous contents, so if you need more fine-grained control, set 163 * per-program buffer with bpf_program__set_log_buf() to preserve each 164 * individual program's verification log. Keep using kernel_log_buf 165 * for BTF verification log, if necessary. 166 */ 167 char *kernel_log_buf; 168 size_t kernel_log_size; 169 /* 170 * Log level can be set independently from log buffer. Log_level=0 171 * means that libbpf will attempt loading BTF or program without any 172 * logging requested, but will retry with either its own or custom log 173 * buffer, if provided, and log_level=1 on any error. 174 * And vice versa, setting log_level>0 will request BTF or prog 175 * loading with verbose log from the first attempt (and as such also 176 * for successfully loaded BTF or program), and the actual log buffer 177 * could be either libbpf's own auto-allocated log buffer, if 178 * kernel_log_buffer is NULL, or user-provided custom kernel_log_buf. 179 * If user didn't provide custom log buffer, libbpf will emit captured 180 * logs through its print callback. 181 */ 182 __u32 kernel_log_level; 183 /* Path to BPF FS mount point to derive BPF token from. 184 * 185 * Created BPF token will be used for all bpf() syscall operations 186 * that accept BPF token (e.g., map creation, BTF and program loads, 187 * etc) automatically within instantiated BPF object. 188 * 189 * If bpf_token_path is not specified, libbpf will consult 190 * LIBBPF_BPF_TOKEN_PATH environment variable. If set, it will be 191 * taken as a value of bpf_token_path option and will force libbpf to 192 * either create BPF token from provided custom BPF FS path, or will 193 * disable implicit BPF token creation, if envvar value is an empty 194 * string. bpf_token_path overrides LIBBPF_BPF_TOKEN_PATH, if both are 195 * set at the same time. 196 * 197 * Setting bpf_token_path option to empty string disables libbpf's 198 * automatic attempt to create BPF token from default BPF FS mount 199 * point (/sys/fs/bpf), in case this default behavior is undesirable. 200 */ 201 const char *bpf_token_path; 202 203 size_t :0; 204 }; 205 #define bpf_object_open_opts__last_field bpf_token_path 206 207 /** 208 * @brief **bpf_object__open()** creates a bpf_object by opening 209 * the BPF ELF object file pointed to by the passed path and loading it 210 * into memory. 211 * @param path BPF object file path. 212 * @return pointer to the new bpf_object; or NULL is returned on error, 213 * error code is stored in errno 214 */ 215 LIBBPF_API struct bpf_object *bpf_object__open(const char *path); 216 217 /** 218 * @brief **bpf_object__open_file()** creates a bpf_object by opening 219 * the BPF ELF object file pointed to by the passed path and loading it 220 * into memory. 221 * @param path BPF object file path 222 * @param opts options for how to load the bpf object, this parameter is 223 * optional and can be set to NULL 224 * @return pointer to the new bpf_object; or NULL is returned on error, 225 * error code is stored in errno 226 */ 227 LIBBPF_API struct bpf_object * 228 bpf_object__open_file(const char *path, const struct bpf_object_open_opts *opts); 229 230 /** 231 * @brief **bpf_object__open_mem()** creates a bpf_object by reading 232 * the BPF objects raw bytes from a memory buffer containing a valid 233 * BPF ELF object file. 234 * @param obj_buf pointer to the buffer containing ELF file bytes 235 * @param obj_buf_sz number of bytes in the buffer 236 * @param opts options for how to load the bpf object 237 * @return pointer to the new bpf_object; or NULL is returned on error, 238 * error code is stored in errno 239 */ 240 LIBBPF_API struct bpf_object * 241 bpf_object__open_mem(const void *obj_buf, size_t obj_buf_sz, 242 const struct bpf_object_open_opts *opts); 243 244 /** 245 * @brief **bpf_object__prepare()** prepares BPF object for loading: 246 * performs ELF processing, relocations, prepares final state of BPF program 247 * instructions (accessible with bpf_program__insns()), creates and 248 * (potentially) pins maps. Leaves BPF object in the state ready for program 249 * loading. 250 * @param obj Pointer to a valid BPF object instance returned by 251 * **bpf_object__open*()** API 252 * @return 0, on success; negative error code, otherwise, error code is 253 * stored in errno 254 */ 255 int bpf_object__prepare(struct bpf_object *obj); 256 257 /** 258 * @brief **bpf_object__load()** loads BPF object into kernel. 259 * @param obj Pointer to a valid BPF object instance returned by 260 * **bpf_object__open*()** APIs 261 * @return 0, on success; negative error code, otherwise, error code is 262 * stored in errno 263 */ 264 LIBBPF_API int bpf_object__load(struct bpf_object *obj); 265 266 /** 267 * @brief **bpf_object__close()** closes a BPF object and releases all 268 * resources. 269 * @param obj Pointer to a valid BPF object 270 */ 271 LIBBPF_API void bpf_object__close(struct bpf_object *obj); 272 273 /** 274 * @brief **bpf_object__pin_maps()** pins each map contained within 275 * the BPF object at the passed directory. 276 * @param obj Pointer to a valid BPF object 277 * @param path A directory where maps should be pinned. 278 * @return 0, on success; negative error code, otherwise 279 * 280 * If `path` is NULL `bpf_map__pin` (which is being used on each map) 281 * will use the pin_path attribute of each map. In this case, maps that 282 * don't have a pin_path set will be ignored. 283 */ 284 LIBBPF_API int bpf_object__pin_maps(struct bpf_object *obj, const char *path); 285 286 /** 287 * @brief **bpf_object__unpin_maps()** unpins each map contained within 288 * the BPF object found in the passed directory. 289 * @param obj Pointer to a valid BPF object 290 * @param path A directory where pinned maps should be searched for. 291 * @return 0, on success; negative error code, otherwise 292 * 293 * If `path` is NULL `bpf_map__unpin` (which is being used on each map) 294 * will use the pin_path attribute of each map. In this case, maps that 295 * don't have a pin_path set will be ignored. 296 */ 297 LIBBPF_API int bpf_object__unpin_maps(struct bpf_object *obj, 298 const char *path); 299 LIBBPF_API int bpf_object__pin_programs(struct bpf_object *obj, 300 const char *path); 301 LIBBPF_API int bpf_object__unpin_programs(struct bpf_object *obj, 302 const char *path); 303 LIBBPF_API int bpf_object__pin(struct bpf_object *object, const char *path); 304 LIBBPF_API int bpf_object__unpin(struct bpf_object *object, const char *path); 305 306 LIBBPF_API const char *bpf_object__name(const struct bpf_object *obj); 307 LIBBPF_API unsigned int bpf_object__kversion(const struct bpf_object *obj); 308 LIBBPF_API int bpf_object__set_kversion(struct bpf_object *obj, __u32 kern_version); 309 310 /** 311 * @brief **bpf_object__token_fd** is an accessor for BPF token FD associated 312 * with BPF object. 313 * @param obj Pointer to a valid BPF object 314 * @return BPF token FD or -1, if it wasn't set 315 */ 316 LIBBPF_API int bpf_object__token_fd(const struct bpf_object *obj); 317 318 struct btf; 319 LIBBPF_API struct btf *bpf_object__btf(const struct bpf_object *obj); 320 LIBBPF_API int bpf_object__btf_fd(const struct bpf_object *obj); 321 322 LIBBPF_API struct bpf_program * 323 bpf_object__find_program_by_name(const struct bpf_object *obj, 324 const char *name); 325 326 LIBBPF_API int 327 libbpf_prog_type_by_name(const char *name, enum bpf_prog_type *prog_type, 328 enum bpf_attach_type *expected_attach_type); 329 LIBBPF_API int libbpf_attach_type_by_name(const char *name, 330 enum bpf_attach_type *attach_type); 331 LIBBPF_API int libbpf_find_vmlinux_btf_id(const char *name, 332 enum bpf_attach_type attach_type); 333 334 /* Accessors of bpf_program */ 335 struct bpf_program; 336 337 LIBBPF_API struct bpf_program * 338 bpf_object__next_program(const struct bpf_object *obj, struct bpf_program *prog); 339 340 #define bpf_object__for_each_program(pos, obj) \ 341 for ((pos) = bpf_object__next_program((obj), NULL); \ 342 (pos) != NULL; \ 343 (pos) = bpf_object__next_program((obj), (pos))) 344 345 LIBBPF_API struct bpf_program * 346 bpf_object__prev_program(const struct bpf_object *obj, struct bpf_program *prog); 347 348 LIBBPF_API void bpf_program__set_ifindex(struct bpf_program *prog, 349 __u32 ifindex); 350 351 LIBBPF_API const char *bpf_program__name(const struct bpf_program *prog); 352 LIBBPF_API const char *bpf_program__section_name(const struct bpf_program *prog); 353 LIBBPF_API bool bpf_program__autoload(const struct bpf_program *prog); 354 LIBBPF_API int bpf_program__set_autoload(struct bpf_program *prog, bool autoload); 355 LIBBPF_API bool bpf_program__autoattach(const struct bpf_program *prog); 356 LIBBPF_API void bpf_program__set_autoattach(struct bpf_program *prog, bool autoattach); 357 358 struct bpf_insn; 359 360 /** 361 * @brief **bpf_program__insns()** gives read-only access to BPF program's 362 * underlying BPF instructions. 363 * @param prog BPF program for which to return instructions 364 * @return a pointer to an array of BPF instructions that belong to the 365 * specified BPF program 366 * 367 * Returned pointer is always valid and not NULL. Number of `struct bpf_insn` 368 * pointed to can be fetched using **bpf_program__insn_cnt()** API. 369 * 370 * Keep in mind, libbpf can modify and append/delete BPF program's 371 * instructions as it processes BPF object file and prepares everything for 372 * uploading into the kernel. So depending on the point in BPF object 373 * lifetime, **bpf_program__insns()** can return different sets of 374 * instructions. As an example, during BPF object load phase BPF program 375 * instructions will be CO-RE-relocated, BPF subprograms instructions will be 376 * appended, ldimm64 instructions will have FDs embedded, etc. So instructions 377 * returned before **bpf_object__load()** and after it might be quite 378 * different. 379 */ 380 LIBBPF_API const struct bpf_insn *bpf_program__insns(const struct bpf_program *prog); 381 382 /** 383 * @brief **bpf_program__set_insns()** can set BPF program's underlying 384 * BPF instructions. 385 * 386 * WARNING: This is a very advanced libbpf API and users need to know 387 * what they are doing. This should be used from prog_prepare_load_fn 388 * callback only. 389 * 390 * @param prog BPF program for which to return instructions 391 * @param new_insns a pointer to an array of BPF instructions 392 * @param new_insn_cnt number of `struct bpf_insn`'s that form 393 * specified BPF program 394 * @return 0, on success; negative error code, otherwise 395 */ 396 LIBBPF_API int bpf_program__set_insns(struct bpf_program *prog, 397 struct bpf_insn *new_insns, size_t new_insn_cnt); 398 399 /** 400 * @brief **bpf_program__insn_cnt()** returns number of `struct bpf_insn`'s 401 * that form specified BPF program. 402 * @param prog BPF program for which to return number of BPF instructions 403 * 404 * See **bpf_program__insns()** documentation for notes on how libbpf can 405 * change instructions and their count during different phases of 406 * **bpf_object** lifetime. 407 */ 408 LIBBPF_API size_t bpf_program__insn_cnt(const struct bpf_program *prog); 409 410 LIBBPF_API int bpf_program__fd(const struct bpf_program *prog); 411 412 /** 413 * @brief **bpf_program__pin()** pins the BPF program to a file 414 * in the BPF FS specified by a path. This increments the programs 415 * reference count, allowing it to stay loaded after the process 416 * which loaded it has exited. 417 * 418 * @param prog BPF program to pin, must already be loaded 419 * @param path file path in a BPF file system 420 * @return 0, on success; negative error code, otherwise 421 */ 422 LIBBPF_API int bpf_program__pin(struct bpf_program *prog, const char *path); 423 424 /** 425 * @brief **bpf_program__unpin()** unpins the BPF program from a file 426 * in the BPFFS specified by a path. This decrements the programs 427 * reference count. 428 * 429 * The file pinning the BPF program can also be unlinked by a different 430 * process in which case this function will return an error. 431 * 432 * @param prog BPF program to unpin 433 * @param path file path to the pin in a BPF file system 434 * @return 0, on success; negative error code, otherwise 435 */ 436 LIBBPF_API int bpf_program__unpin(struct bpf_program *prog, const char *path); 437 LIBBPF_API void bpf_program__unload(struct bpf_program *prog); 438 439 struct bpf_link; 440 441 LIBBPF_API struct bpf_link *bpf_link__open(const char *path); 442 LIBBPF_API int bpf_link__fd(const struct bpf_link *link); 443 LIBBPF_API const char *bpf_link__pin_path(const struct bpf_link *link); 444 /** 445 * @brief **bpf_link__pin()** pins the BPF link to a file 446 * in the BPF FS specified by a path. This increments the links 447 * reference count, allowing it to stay loaded after the process 448 * which loaded it has exited. 449 * 450 * @param link BPF link to pin, must already be loaded 451 * @param path file path in a BPF file system 452 * @return 0, on success; negative error code, otherwise 453 */ 454 455 LIBBPF_API int bpf_link__pin(struct bpf_link *link, const char *path); 456 457 /** 458 * @brief **bpf_link__unpin()** unpins the BPF link from a file 459 * in the BPFFS specified by a path. This decrements the links 460 * reference count. 461 * 462 * The file pinning the BPF link can also be unlinked by a different 463 * process in which case this function will return an error. 464 * 465 * @param prog BPF program to unpin 466 * @param path file path to the pin in a BPF file system 467 * @return 0, on success; negative error code, otherwise 468 */ 469 LIBBPF_API int bpf_link__unpin(struct bpf_link *link); 470 LIBBPF_API int bpf_link__update_program(struct bpf_link *link, 471 struct bpf_program *prog); 472 LIBBPF_API void bpf_link__disconnect(struct bpf_link *link); 473 LIBBPF_API int bpf_link__detach(struct bpf_link *link); 474 LIBBPF_API int bpf_link__destroy(struct bpf_link *link); 475 476 /** 477 * @brief **bpf_program__attach()** is a generic function for attaching 478 * a BPF program based on auto-detection of program type, attach type, 479 * and extra parameters, where applicable. 480 * 481 * @param prog BPF program to attach 482 * @return Reference to the newly created BPF link; or NULL is returned on error, 483 * error code is stored in errno 484 * 485 * This is supported for: 486 * - kprobe/kretprobe (depends on SEC() definition) 487 * - uprobe/uretprobe (depends on SEC() definition) 488 * - tracepoint 489 * - raw tracepoint 490 * - tracing programs (typed raw TP/fentry/fexit/fmod_ret) 491 */ 492 LIBBPF_API struct bpf_link * 493 bpf_program__attach(const struct bpf_program *prog); 494 495 struct bpf_perf_event_opts { 496 /* size of this struct, for forward/backward compatibility */ 497 size_t sz; 498 /* custom user-provided value fetchable through bpf_get_attach_cookie() */ 499 __u64 bpf_cookie; 500 /* don't use BPF link when attach BPF program */ 501 bool force_ioctl_attach; 502 size_t :0; 503 }; 504 #define bpf_perf_event_opts__last_field force_ioctl_attach 505 506 LIBBPF_API struct bpf_link * 507 bpf_program__attach_perf_event(const struct bpf_program *prog, int pfd); 508 509 LIBBPF_API struct bpf_link * 510 bpf_program__attach_perf_event_opts(const struct bpf_program *prog, int pfd, 511 const struct bpf_perf_event_opts *opts); 512 513 /** 514 * enum probe_attach_mode - the mode to attach kprobe/uprobe 515 * 516 * force libbpf to attach kprobe/uprobe in specific mode, -ENOTSUP will 517 * be returned if it is not supported by the kernel. 518 */ 519 enum probe_attach_mode { 520 /* attach probe in latest supported mode by kernel */ 521 PROBE_ATTACH_MODE_DEFAULT = 0, 522 /* attach probe in legacy mode, using debugfs/tracefs */ 523 PROBE_ATTACH_MODE_LEGACY, 524 /* create perf event with perf_event_open() syscall */ 525 PROBE_ATTACH_MODE_PERF, 526 /* attach probe with BPF link */ 527 PROBE_ATTACH_MODE_LINK, 528 }; 529 530 struct bpf_kprobe_opts { 531 /* size of this struct, for forward/backward compatibility */ 532 size_t sz; 533 /* custom user-provided value fetchable through bpf_get_attach_cookie() */ 534 __u64 bpf_cookie; 535 /* function's offset to install kprobe to */ 536 size_t offset; 537 /* kprobe is return probe */ 538 bool retprobe; 539 /* kprobe attach mode */ 540 enum probe_attach_mode attach_mode; 541 size_t :0; 542 }; 543 #define bpf_kprobe_opts__last_field attach_mode 544 545 LIBBPF_API struct bpf_link * 546 bpf_program__attach_kprobe(const struct bpf_program *prog, bool retprobe, 547 const char *func_name); 548 LIBBPF_API struct bpf_link * 549 bpf_program__attach_kprobe_opts(const struct bpf_program *prog, 550 const char *func_name, 551 const struct bpf_kprobe_opts *opts); 552 553 struct bpf_kprobe_multi_opts { 554 /* size of this struct, for forward/backward compatibility */ 555 size_t sz; 556 /* array of function symbols to attach */ 557 const char **syms; 558 /* array of function addresses to attach */ 559 const unsigned long *addrs; 560 /* array of user-provided values fetchable through bpf_get_attach_cookie */ 561 const __u64 *cookies; 562 /* number of elements in syms/addrs/cookies arrays */ 563 size_t cnt; 564 /* create return kprobes */ 565 bool retprobe; 566 /* create session kprobes */ 567 bool session; 568 /* enforce unique match */ 569 bool unique_match; 570 size_t :0; 571 }; 572 573 #define bpf_kprobe_multi_opts__last_field unique_match 574 575 LIBBPF_API struct bpf_link * 576 bpf_program__attach_kprobe_multi_opts(const struct bpf_program *prog, 577 const char *pattern, 578 const struct bpf_kprobe_multi_opts *opts); 579 580 struct bpf_uprobe_multi_opts { 581 /* size of this struct, for forward/backward compatibility */ 582 size_t sz; 583 /* array of function symbols to attach to */ 584 const char **syms; 585 /* array of function addresses to attach to */ 586 const unsigned long *offsets; 587 /* optional, array of associated ref counter offsets */ 588 const unsigned long *ref_ctr_offsets; 589 /* optional, array of associated BPF cookies */ 590 const __u64 *cookies; 591 /* number of elements in syms/addrs/cookies arrays */ 592 size_t cnt; 593 /* create return uprobes */ 594 bool retprobe; 595 /* create session kprobes */ 596 bool session; 597 size_t :0; 598 }; 599 600 #define bpf_uprobe_multi_opts__last_field session 601 602 /** 603 * @brief **bpf_program__attach_uprobe_multi()** attaches a BPF program 604 * to multiple uprobes with uprobe_multi link. 605 * 606 * User can specify 2 mutually exclusive set of inputs: 607 * 608 * 1) use only path/func_pattern/pid arguments 609 * 610 * 2) use path/pid with allowed combinations of 611 * syms/offsets/ref_ctr_offsets/cookies/cnt 612 * 613 * - syms and offsets are mutually exclusive 614 * - ref_ctr_offsets and cookies are optional 615 * 616 * 617 * @param prog BPF program to attach 618 * @param pid Process ID to attach the uprobe to, 0 for self (own process), 619 * -1 for all processes 620 * @param binary_path Path to binary 621 * @param func_pattern Regular expression to specify functions to attach 622 * BPF program to 623 * @param opts Additional options (see **struct bpf_uprobe_multi_opts**) 624 * @return 0, on success; negative error code, otherwise 625 */ 626 LIBBPF_API struct bpf_link * 627 bpf_program__attach_uprobe_multi(const struct bpf_program *prog, 628 pid_t pid, 629 const char *binary_path, 630 const char *func_pattern, 631 const struct bpf_uprobe_multi_opts *opts); 632 633 struct bpf_ksyscall_opts { 634 /* size of this struct, for forward/backward compatibility */ 635 size_t sz; 636 /* custom user-provided value fetchable through bpf_get_attach_cookie() */ 637 __u64 bpf_cookie; 638 /* attach as return probe? */ 639 bool retprobe; 640 size_t :0; 641 }; 642 #define bpf_ksyscall_opts__last_field retprobe 643 644 /** 645 * @brief **bpf_program__attach_ksyscall()** attaches a BPF program 646 * to kernel syscall handler of a specified syscall. Optionally it's possible 647 * to request to install retprobe that will be triggered at syscall exit. It's 648 * also possible to associate BPF cookie (though options). 649 * 650 * Libbpf automatically will determine correct full kernel function name, 651 * which depending on system architecture and kernel version/configuration 652 * could be of the form __<arch>_sys_<syscall> or __se_sys_<syscall>, and will 653 * attach specified program using kprobe/kretprobe mechanism. 654 * 655 * **bpf_program__attach_ksyscall()** is an API counterpart of declarative 656 * **SEC("ksyscall/<syscall>")** annotation of BPF programs. 657 * 658 * At the moment **SEC("ksyscall")** and **bpf_program__attach_ksyscall()** do 659 * not handle all the calling convention quirks for mmap(), clone() and compat 660 * syscalls. It also only attaches to "native" syscall interfaces. If host 661 * system supports compat syscalls or defines 32-bit syscalls in 64-bit 662 * kernel, such syscall interfaces won't be attached to by libbpf. 663 * 664 * These limitations may or may not change in the future. Therefore it is 665 * recommended to use SEC("kprobe") for these syscalls or if working with 666 * compat and 32-bit interfaces is required. 667 * 668 * @param prog BPF program to attach 669 * @param syscall_name Symbolic name of the syscall (e.g., "bpf") 670 * @param opts Additional options (see **struct bpf_ksyscall_opts**) 671 * @return Reference to the newly created BPF link; or NULL is returned on 672 * error, error code is stored in errno 673 */ 674 LIBBPF_API struct bpf_link * 675 bpf_program__attach_ksyscall(const struct bpf_program *prog, 676 const char *syscall_name, 677 const struct bpf_ksyscall_opts *opts); 678 679 struct bpf_uprobe_opts { 680 /* size of this struct, for forward/backward compatibility */ 681 size_t sz; 682 /* offset of kernel reference counted USDT semaphore, added in 683 * a6ca88b241d5 ("trace_uprobe: support reference counter in fd-based uprobe") 684 */ 685 size_t ref_ctr_offset; 686 /* custom user-provided value fetchable through bpf_get_attach_cookie() */ 687 __u64 bpf_cookie; 688 /* uprobe is return probe, invoked at function return time */ 689 bool retprobe; 690 /* Function name to attach to. Could be an unqualified ("abc") or library-qualified 691 * "abc@LIBXYZ" name. To specify function entry, func_name should be set while 692 * func_offset argument to bpf_prog__attach_uprobe_opts() should be 0. To trace an 693 * offset within a function, specify func_name and use func_offset argument to specify 694 * offset within the function. Shared library functions must specify the shared library 695 * binary_path. 696 */ 697 const char *func_name; 698 /* uprobe attach mode */ 699 enum probe_attach_mode attach_mode; 700 size_t :0; 701 }; 702 #define bpf_uprobe_opts__last_field attach_mode 703 704 /** 705 * @brief **bpf_program__attach_uprobe()** attaches a BPF program 706 * to the userspace function which is found by binary path and 707 * offset. You can optionally specify a particular process to attach 708 * to. You can also optionally attach the program to the function 709 * exit instead of entry. 710 * 711 * @param prog BPF program to attach 712 * @param retprobe Attach to function exit 713 * @param pid Process ID to attach the uprobe to, 0 for self (own process), 714 * -1 for all processes 715 * @param binary_path Path to binary that contains the function symbol 716 * @param func_offset Offset within the binary of the function symbol 717 * @return Reference to the newly created BPF link; or NULL is returned on error, 718 * error code is stored in errno 719 */ 720 LIBBPF_API struct bpf_link * 721 bpf_program__attach_uprobe(const struct bpf_program *prog, bool retprobe, 722 pid_t pid, const char *binary_path, 723 size_t func_offset); 724 725 /** 726 * @brief **bpf_program__attach_uprobe_opts()** is just like 727 * bpf_program__attach_uprobe() except with a options struct 728 * for various configurations. 729 * 730 * @param prog BPF program to attach 731 * @param pid Process ID to attach the uprobe to, 0 for self (own process), 732 * -1 for all processes 733 * @param binary_path Path to binary that contains the function symbol 734 * @param func_offset Offset within the binary of the function symbol 735 * @param opts Options for altering program attachment 736 * @return Reference to the newly created BPF link; or NULL is returned on error, 737 * error code is stored in errno 738 */ 739 LIBBPF_API struct bpf_link * 740 bpf_program__attach_uprobe_opts(const struct bpf_program *prog, pid_t pid, 741 const char *binary_path, size_t func_offset, 742 const struct bpf_uprobe_opts *opts); 743 744 struct bpf_usdt_opts { 745 /* size of this struct, for forward/backward compatibility */ 746 size_t sz; 747 /* custom user-provided value accessible through usdt_cookie() */ 748 __u64 usdt_cookie; 749 size_t :0; 750 }; 751 #define bpf_usdt_opts__last_field usdt_cookie 752 753 /** 754 * @brief **bpf_program__attach_usdt()** is just like 755 * bpf_program__attach_uprobe_opts() except it covers USDT (User-space 756 * Statically Defined Tracepoint) attachment, instead of attaching to 757 * user-space function entry or exit. 758 * 759 * @param prog BPF program to attach 760 * @param pid Process ID to attach the uprobe to, 0 for self (own process), 761 * -1 for all processes 762 * @param binary_path Path to binary that contains provided USDT probe 763 * @param usdt_provider USDT provider name 764 * @param usdt_name USDT probe name 765 * @param opts Options for altering program attachment 766 * @return Reference to the newly created BPF link; or NULL is returned on error, 767 * error code is stored in errno 768 */ 769 LIBBPF_API struct bpf_link * 770 bpf_program__attach_usdt(const struct bpf_program *prog, 771 pid_t pid, const char *binary_path, 772 const char *usdt_provider, const char *usdt_name, 773 const struct bpf_usdt_opts *opts); 774 775 struct bpf_tracepoint_opts { 776 /* size of this struct, for forward/backward compatibility */ 777 size_t sz; 778 /* custom user-provided value fetchable through bpf_get_attach_cookie() */ 779 __u64 bpf_cookie; 780 }; 781 #define bpf_tracepoint_opts__last_field bpf_cookie 782 783 LIBBPF_API struct bpf_link * 784 bpf_program__attach_tracepoint(const struct bpf_program *prog, 785 const char *tp_category, 786 const char *tp_name); 787 LIBBPF_API struct bpf_link * 788 bpf_program__attach_tracepoint_opts(const struct bpf_program *prog, 789 const char *tp_category, 790 const char *tp_name, 791 const struct bpf_tracepoint_opts *opts); 792 793 struct bpf_raw_tracepoint_opts { 794 size_t sz; /* size of this struct for forward/backward compatibility */ 795 __u64 cookie; 796 size_t :0; 797 }; 798 #define bpf_raw_tracepoint_opts__last_field cookie 799 800 LIBBPF_API struct bpf_link * 801 bpf_program__attach_raw_tracepoint(const struct bpf_program *prog, 802 const char *tp_name); 803 LIBBPF_API struct bpf_link * 804 bpf_program__attach_raw_tracepoint_opts(const struct bpf_program *prog, 805 const char *tp_name, 806 struct bpf_raw_tracepoint_opts *opts); 807 808 struct bpf_trace_opts { 809 /* size of this struct, for forward/backward compatibility */ 810 size_t sz; 811 /* custom user-provided value fetchable through bpf_get_attach_cookie() */ 812 __u64 cookie; 813 }; 814 #define bpf_trace_opts__last_field cookie 815 816 LIBBPF_API struct bpf_link * 817 bpf_program__attach_trace(const struct bpf_program *prog); 818 LIBBPF_API struct bpf_link * 819 bpf_program__attach_trace_opts(const struct bpf_program *prog, const struct bpf_trace_opts *opts); 820 821 LIBBPF_API struct bpf_link * 822 bpf_program__attach_lsm(const struct bpf_program *prog); 823 LIBBPF_API struct bpf_link * 824 bpf_program__attach_cgroup(const struct bpf_program *prog, int cgroup_fd); 825 LIBBPF_API struct bpf_link * 826 bpf_program__attach_netns(const struct bpf_program *prog, int netns_fd); 827 LIBBPF_API struct bpf_link * 828 bpf_program__attach_sockmap(const struct bpf_program *prog, int map_fd); 829 LIBBPF_API struct bpf_link * 830 bpf_program__attach_xdp(const struct bpf_program *prog, int ifindex); 831 LIBBPF_API struct bpf_link * 832 bpf_program__attach_freplace(const struct bpf_program *prog, 833 int target_fd, const char *attach_func_name); 834 835 struct bpf_netfilter_opts { 836 /* size of this struct, for forward/backward compatibility */ 837 size_t sz; 838 839 __u32 pf; 840 __u32 hooknum; 841 __s32 priority; 842 __u32 flags; 843 }; 844 #define bpf_netfilter_opts__last_field flags 845 846 LIBBPF_API struct bpf_link * 847 bpf_program__attach_netfilter(const struct bpf_program *prog, 848 const struct bpf_netfilter_opts *opts); 849 850 struct bpf_tcx_opts { 851 /* size of this struct, for forward/backward compatibility */ 852 size_t sz; 853 __u32 flags; 854 __u32 relative_fd; 855 __u32 relative_id; 856 __u64 expected_revision; 857 size_t :0; 858 }; 859 #define bpf_tcx_opts__last_field expected_revision 860 861 LIBBPF_API struct bpf_link * 862 bpf_program__attach_tcx(const struct bpf_program *prog, int ifindex, 863 const struct bpf_tcx_opts *opts); 864 865 struct bpf_netkit_opts { 866 /* size of this struct, for forward/backward compatibility */ 867 size_t sz; 868 __u32 flags; 869 __u32 relative_fd; 870 __u32 relative_id; 871 __u64 expected_revision; 872 size_t :0; 873 }; 874 #define bpf_netkit_opts__last_field expected_revision 875 876 LIBBPF_API struct bpf_link * 877 bpf_program__attach_netkit(const struct bpf_program *prog, int ifindex, 878 const struct bpf_netkit_opts *opts); 879 880 struct bpf_map; 881 882 LIBBPF_API struct bpf_link *bpf_map__attach_struct_ops(const struct bpf_map *map); 883 LIBBPF_API int bpf_link__update_map(struct bpf_link *link, const struct bpf_map *map); 884 885 struct bpf_iter_attach_opts { 886 size_t sz; /* size of this struct for forward/backward compatibility */ 887 union bpf_iter_link_info *link_info; 888 __u32 link_info_len; 889 }; 890 #define bpf_iter_attach_opts__last_field link_info_len 891 892 LIBBPF_API struct bpf_link * 893 bpf_program__attach_iter(const struct bpf_program *prog, 894 const struct bpf_iter_attach_opts *opts); 895 896 LIBBPF_API enum bpf_prog_type bpf_program__type(const struct bpf_program *prog); 897 898 /** 899 * @brief **bpf_program__set_type()** sets the program 900 * type of the passed BPF program. 901 * @param prog BPF program to set the program type for 902 * @param type program type to set the BPF map to have 903 * @return error code; or 0 if no error. An error occurs 904 * if the object is already loaded. 905 * 906 * This must be called before the BPF object is loaded, 907 * otherwise it has no effect and an error is returned. 908 */ 909 LIBBPF_API int bpf_program__set_type(struct bpf_program *prog, 910 enum bpf_prog_type type); 911 912 LIBBPF_API enum bpf_attach_type 913 bpf_program__expected_attach_type(const struct bpf_program *prog); 914 915 /** 916 * @brief **bpf_program__set_expected_attach_type()** sets the 917 * attach type of the passed BPF program. This is used for 918 * auto-detection of attachment when programs are loaded. 919 * @param prog BPF program to set the attach type for 920 * @param type attach type to set the BPF map to have 921 * @return error code; or 0 if no error. An error occurs 922 * if the object is already loaded. 923 * 924 * This must be called before the BPF object is loaded, 925 * otherwise it has no effect and an error is returned. 926 */ 927 LIBBPF_API int 928 bpf_program__set_expected_attach_type(struct bpf_program *prog, 929 enum bpf_attach_type type); 930 931 LIBBPF_API __u32 bpf_program__flags(const struct bpf_program *prog); 932 LIBBPF_API int bpf_program__set_flags(struct bpf_program *prog, __u32 flags); 933 934 /* Per-program log level and log buffer getters/setters. 935 * See bpf_object_open_opts comments regarding log_level and log_buf 936 * interactions. 937 */ 938 LIBBPF_API __u32 bpf_program__log_level(const struct bpf_program *prog); 939 LIBBPF_API int bpf_program__set_log_level(struct bpf_program *prog, __u32 log_level); 940 LIBBPF_API const char *bpf_program__log_buf(const struct bpf_program *prog, size_t *log_size); 941 LIBBPF_API int bpf_program__set_log_buf(struct bpf_program *prog, char *log_buf, size_t log_size); 942 943 /** 944 * @brief **bpf_program__set_attach_target()** sets BTF-based attach target 945 * for supported BPF program types: 946 * - BTF-aware raw tracepoints (tp_btf); 947 * - fentry/fexit/fmod_ret; 948 * - lsm; 949 * - freplace. 950 * @param prog BPF program to set the attach type for 951 * @param type attach type to set the BPF map to have 952 * @return error code; or 0 if no error occurred. 953 */ 954 LIBBPF_API int 955 bpf_program__set_attach_target(struct bpf_program *prog, int attach_prog_fd, 956 const char *attach_func_name); 957 958 /** 959 * @brief **bpf_object__find_map_by_name()** returns BPF map of 960 * the given name, if it exists within the passed BPF object 961 * @param obj BPF object 962 * @param name name of the BPF map 963 * @return BPF map instance, if such map exists within the BPF object; 964 * or NULL otherwise. 965 */ 966 LIBBPF_API struct bpf_map * 967 bpf_object__find_map_by_name(const struct bpf_object *obj, const char *name); 968 969 LIBBPF_API int 970 bpf_object__find_map_fd_by_name(const struct bpf_object *obj, const char *name); 971 972 LIBBPF_API struct bpf_map * 973 bpf_object__next_map(const struct bpf_object *obj, const struct bpf_map *map); 974 975 #define bpf_object__for_each_map(pos, obj) \ 976 for ((pos) = bpf_object__next_map((obj), NULL); \ 977 (pos) != NULL; \ 978 (pos) = bpf_object__next_map((obj), (pos))) 979 #define bpf_map__for_each bpf_object__for_each_map 980 981 LIBBPF_API struct bpf_map * 982 bpf_object__prev_map(const struct bpf_object *obj, const struct bpf_map *map); 983 984 /** 985 * @brief **bpf_map__set_autocreate()** sets whether libbpf has to auto-create 986 * BPF map during BPF object load phase. 987 * @param map the BPF map instance 988 * @param autocreate whether to create BPF map during BPF object load 989 * @return 0 on success; -EBUSY if BPF object was already loaded 990 * 991 * **bpf_map__set_autocreate()** allows to opt-out from libbpf auto-creating 992 * BPF map. By default, libbpf will attempt to create every single BPF map 993 * defined in BPF object file using BPF_MAP_CREATE command of bpf() syscall 994 * and fill in map FD in BPF instructions. 995 * 996 * This API allows to opt-out of this process for specific map instance. This 997 * can be useful if host kernel doesn't support such BPF map type or used 998 * combination of flags and user application wants to avoid creating such 999 * a map in the first place. User is still responsible to make sure that their 1000 * BPF-side code that expects to use such missing BPF map is recognized by BPF 1001 * verifier as dead code, otherwise BPF verifier will reject such BPF program. 1002 */ 1003 LIBBPF_API int bpf_map__set_autocreate(struct bpf_map *map, bool autocreate); 1004 LIBBPF_API bool bpf_map__autocreate(const struct bpf_map *map); 1005 1006 /** 1007 * @brief **bpf_map__set_autoattach()** sets whether libbpf has to auto-attach 1008 * map during BPF skeleton attach phase. 1009 * @param map the BPF map instance 1010 * @param autoattach whether to attach map during BPF skeleton attach phase 1011 * @return 0 on success; negative error code, otherwise 1012 */ 1013 LIBBPF_API int bpf_map__set_autoattach(struct bpf_map *map, bool autoattach); 1014 1015 /** 1016 * @brief **bpf_map__autoattach()** returns whether BPF map is configured to 1017 * auto-attach during BPF skeleton attach phase. 1018 * @param map the BPF map instance 1019 * @return true if map is set to auto-attach during skeleton attach phase; false, otherwise 1020 */ 1021 LIBBPF_API bool bpf_map__autoattach(const struct bpf_map *map); 1022 1023 /** 1024 * @brief **bpf_map__fd()** gets the file descriptor of the passed 1025 * BPF map 1026 * @param map the BPF map instance 1027 * @return the file descriptor; or -EINVAL in case of an error 1028 */ 1029 LIBBPF_API int bpf_map__fd(const struct bpf_map *map); 1030 LIBBPF_API int bpf_map__reuse_fd(struct bpf_map *map, int fd); 1031 /* get map name */ 1032 LIBBPF_API const char *bpf_map__name(const struct bpf_map *map); 1033 /* get/set map type */ 1034 LIBBPF_API enum bpf_map_type bpf_map__type(const struct bpf_map *map); 1035 LIBBPF_API int bpf_map__set_type(struct bpf_map *map, enum bpf_map_type type); 1036 /* get/set map size (max_entries) */ 1037 LIBBPF_API __u32 bpf_map__max_entries(const struct bpf_map *map); 1038 LIBBPF_API int bpf_map__set_max_entries(struct bpf_map *map, __u32 max_entries); 1039 /* get/set map flags */ 1040 LIBBPF_API __u32 bpf_map__map_flags(const struct bpf_map *map); 1041 LIBBPF_API int bpf_map__set_map_flags(struct bpf_map *map, __u32 flags); 1042 /* get/set map NUMA node */ 1043 LIBBPF_API __u32 bpf_map__numa_node(const struct bpf_map *map); 1044 LIBBPF_API int bpf_map__set_numa_node(struct bpf_map *map, __u32 numa_node); 1045 /* get/set map key size */ 1046 LIBBPF_API __u32 bpf_map__key_size(const struct bpf_map *map); 1047 LIBBPF_API int bpf_map__set_key_size(struct bpf_map *map, __u32 size); 1048 /* get map value size */ 1049 LIBBPF_API __u32 bpf_map__value_size(const struct bpf_map *map); 1050 /** 1051 * @brief **bpf_map__set_value_size()** sets map value size. 1052 * @param map the BPF map instance 1053 * @return 0, on success; negative error, otherwise 1054 * 1055 * There is a special case for maps with associated memory-mapped regions, like 1056 * the global data section maps (bss, data, rodata). When this function is used 1057 * on such a map, the mapped region is resized. Afterward, an attempt is made to 1058 * adjust the corresponding BTF info. This attempt is best-effort and can only 1059 * succeed if the last variable of the data section map is an array. The array 1060 * BTF type is replaced by a new BTF array type with a different length. 1061 * Any previously existing pointers returned from bpf_map__initial_value() or 1062 * corresponding data section skeleton pointer must be reinitialized. 1063 */ 1064 LIBBPF_API int bpf_map__set_value_size(struct bpf_map *map, __u32 size); 1065 /* get map key/value BTF type IDs */ 1066 LIBBPF_API __u32 bpf_map__btf_key_type_id(const struct bpf_map *map); 1067 LIBBPF_API __u32 bpf_map__btf_value_type_id(const struct bpf_map *map); 1068 /* get/set map if_index */ 1069 LIBBPF_API __u32 bpf_map__ifindex(const struct bpf_map *map); 1070 LIBBPF_API int bpf_map__set_ifindex(struct bpf_map *map, __u32 ifindex); 1071 /* get/set map map_extra flags */ 1072 LIBBPF_API __u64 bpf_map__map_extra(const struct bpf_map *map); 1073 LIBBPF_API int bpf_map__set_map_extra(struct bpf_map *map, __u64 map_extra); 1074 1075 LIBBPF_API int bpf_map__set_initial_value(struct bpf_map *map, 1076 const void *data, size_t size); 1077 LIBBPF_API void *bpf_map__initial_value(const struct bpf_map *map, size_t *psize); 1078 1079 /** 1080 * @brief **bpf_map__is_internal()** tells the caller whether or not the 1081 * passed map is a special map created by libbpf automatically for things like 1082 * global variables, __ksym externs, Kconfig values, etc 1083 * @param map the bpf_map 1084 * @return true, if the map is an internal map; false, otherwise 1085 */ 1086 LIBBPF_API bool bpf_map__is_internal(const struct bpf_map *map); 1087 1088 /** 1089 * @brief **bpf_map__set_pin_path()** sets the path attribute that tells where the 1090 * BPF map should be pinned. This does not actually create the 'pin'. 1091 * @param map The bpf_map 1092 * @param path The path 1093 * @return 0, on success; negative error, otherwise 1094 */ 1095 LIBBPF_API int bpf_map__set_pin_path(struct bpf_map *map, const char *path); 1096 1097 /** 1098 * @brief **bpf_map__pin_path()** gets the path attribute that tells where the 1099 * BPF map should be pinned. 1100 * @param map The bpf_map 1101 * @return The path string; which can be NULL 1102 */ 1103 LIBBPF_API const char *bpf_map__pin_path(const struct bpf_map *map); 1104 1105 /** 1106 * @brief **bpf_map__is_pinned()** tells the caller whether or not the 1107 * passed map has been pinned via a 'pin' file. 1108 * @param map The bpf_map 1109 * @return true, if the map is pinned; false, otherwise 1110 */ 1111 LIBBPF_API bool bpf_map__is_pinned(const struct bpf_map *map); 1112 1113 /** 1114 * @brief **bpf_map__pin()** creates a file that serves as a 'pin' 1115 * for the BPF map. This increments the reference count on the 1116 * BPF map which will keep the BPF map loaded even after the 1117 * userspace process which loaded it has exited. 1118 * @param map The bpf_map to pin 1119 * @param path A file path for the 'pin' 1120 * @return 0, on success; negative error, otherwise 1121 * 1122 * If `path` is NULL the maps `pin_path` attribute will be used. If this is 1123 * also NULL, an error will be returned and the map will not be pinned. 1124 */ 1125 LIBBPF_API int bpf_map__pin(struct bpf_map *map, const char *path); 1126 1127 /** 1128 * @brief **bpf_map__unpin()** removes the file that serves as a 1129 * 'pin' for the BPF map. 1130 * @param map The bpf_map to unpin 1131 * @param path A file path for the 'pin' 1132 * @return 0, on success; negative error, otherwise 1133 * 1134 * The `path` parameter can be NULL, in which case the `pin_path` 1135 * map attribute is unpinned. If both the `path` parameter and 1136 * `pin_path` map attribute are set, they must be equal. 1137 */ 1138 LIBBPF_API int bpf_map__unpin(struct bpf_map *map, const char *path); 1139 1140 LIBBPF_API int bpf_map__set_inner_map_fd(struct bpf_map *map, int fd); 1141 LIBBPF_API struct bpf_map *bpf_map__inner_map(struct bpf_map *map); 1142 1143 /** 1144 * @brief **bpf_map__lookup_elem()** allows to lookup BPF map value 1145 * corresponding to provided key. 1146 * @param map BPF map to lookup element in 1147 * @param key pointer to memory containing bytes of the key used for lookup 1148 * @param key_sz size in bytes of key data, needs to match BPF map definition's **key_size** 1149 * @param value pointer to memory in which looked up value will be stored 1150 * @param value_sz size in byte of value data memory; it has to match BPF map 1151 * definition's **value_size**. For per-CPU BPF maps value size has to be 1152 * a product of BPF map value size and number of possible CPUs in the system 1153 * (could be fetched with **libbpf_num_possible_cpus()**). Note also that for 1154 * per-CPU values value size has to be aligned up to closest 8 bytes for 1155 * alignment reasons, so expected size is: `round_up(value_size, 8) 1156 * * libbpf_num_possible_cpus()`. 1157 * @flags extra flags passed to kernel for this operation 1158 * @return 0, on success; negative error, otherwise 1159 * 1160 * **bpf_map__lookup_elem()** is high-level equivalent of 1161 * **bpf_map_lookup_elem()** API with added check for key and value size. 1162 */ 1163 LIBBPF_API int bpf_map__lookup_elem(const struct bpf_map *map, 1164 const void *key, size_t key_sz, 1165 void *value, size_t value_sz, __u64 flags); 1166 1167 /** 1168 * @brief **bpf_map__update_elem()** allows to insert or update value in BPF 1169 * map that corresponds to provided key. 1170 * @param map BPF map to insert to or update element in 1171 * @param key pointer to memory containing bytes of the key 1172 * @param key_sz size in bytes of key data, needs to match BPF map definition's **key_size** 1173 * @param value pointer to memory containing bytes of the value 1174 * @param value_sz size in byte of value data memory; it has to match BPF map 1175 * definition's **value_size**. For per-CPU BPF maps value size has to be 1176 * a product of BPF map value size and number of possible CPUs in the system 1177 * (could be fetched with **libbpf_num_possible_cpus()**). Note also that for 1178 * per-CPU values value size has to be aligned up to closest 8 bytes for 1179 * alignment reasons, so expected size is: `round_up(value_size, 8) 1180 * * libbpf_num_possible_cpus()`. 1181 * @flags extra flags passed to kernel for this operation 1182 * @return 0, on success; negative error, otherwise 1183 * 1184 * **bpf_map__update_elem()** is high-level equivalent of 1185 * **bpf_map_update_elem()** API with added check for key and value size. 1186 */ 1187 LIBBPF_API int bpf_map__update_elem(const struct bpf_map *map, 1188 const void *key, size_t key_sz, 1189 const void *value, size_t value_sz, __u64 flags); 1190 1191 /** 1192 * @brief **bpf_map__delete_elem()** allows to delete element in BPF map that 1193 * corresponds to provided key. 1194 * @param map BPF map to delete element from 1195 * @param key pointer to memory containing bytes of the key 1196 * @param key_sz size in bytes of key data, needs to match BPF map definition's **key_size** 1197 * @flags extra flags passed to kernel for this operation 1198 * @return 0, on success; negative error, otherwise 1199 * 1200 * **bpf_map__delete_elem()** is high-level equivalent of 1201 * **bpf_map_delete_elem()** API with added check for key size. 1202 */ 1203 LIBBPF_API int bpf_map__delete_elem(const struct bpf_map *map, 1204 const void *key, size_t key_sz, __u64 flags); 1205 1206 /** 1207 * @brief **bpf_map__lookup_and_delete_elem()** allows to lookup BPF map value 1208 * corresponding to provided key and atomically delete it afterwards. 1209 * @param map BPF map to lookup element in 1210 * @param key pointer to memory containing bytes of the key used for lookup 1211 * @param key_sz size in bytes of key data, needs to match BPF map definition's **key_size** 1212 * @param value pointer to memory in which looked up value will be stored 1213 * @param value_sz size in byte of value data memory; it has to match BPF map 1214 * definition's **value_size**. For per-CPU BPF maps value size has to be 1215 * a product of BPF map value size and number of possible CPUs in the system 1216 * (could be fetched with **libbpf_num_possible_cpus()**). Note also that for 1217 * per-CPU values value size has to be aligned up to closest 8 bytes for 1218 * alignment reasons, so expected size is: `round_up(value_size, 8) 1219 * * libbpf_num_possible_cpus()`. 1220 * @flags extra flags passed to kernel for this operation 1221 * @return 0, on success; negative error, otherwise 1222 * 1223 * **bpf_map__lookup_and_delete_elem()** is high-level equivalent of 1224 * **bpf_map_lookup_and_delete_elem()** API with added check for key and value size. 1225 */ 1226 LIBBPF_API int bpf_map__lookup_and_delete_elem(const struct bpf_map *map, 1227 const void *key, size_t key_sz, 1228 void *value, size_t value_sz, __u64 flags); 1229 1230 /** 1231 * @brief **bpf_map__get_next_key()** allows to iterate BPF map keys by 1232 * fetching next key that follows current key. 1233 * @param map BPF map to fetch next key from 1234 * @param cur_key pointer to memory containing bytes of current key or NULL to 1235 * fetch the first key 1236 * @param next_key pointer to memory to write next key into 1237 * @param key_sz size in bytes of key data, needs to match BPF map definition's **key_size** 1238 * @return 0, on success; -ENOENT if **cur_key** is the last key in BPF map; 1239 * negative error, otherwise 1240 * 1241 * **bpf_map__get_next_key()** is high-level equivalent of 1242 * **bpf_map_get_next_key()** API with added check for key size. 1243 */ 1244 LIBBPF_API int bpf_map__get_next_key(const struct bpf_map *map, 1245 const void *cur_key, void *next_key, size_t key_sz); 1246 1247 struct bpf_xdp_set_link_opts { 1248 size_t sz; 1249 int old_fd; 1250 size_t :0; 1251 }; 1252 #define bpf_xdp_set_link_opts__last_field old_fd 1253 1254 struct bpf_xdp_attach_opts { 1255 size_t sz; 1256 int old_prog_fd; 1257 size_t :0; 1258 }; 1259 #define bpf_xdp_attach_opts__last_field old_prog_fd 1260 1261 struct bpf_xdp_query_opts { 1262 size_t sz; 1263 __u32 prog_id; /* output */ 1264 __u32 drv_prog_id; /* output */ 1265 __u32 hw_prog_id; /* output */ 1266 __u32 skb_prog_id; /* output */ 1267 __u8 attach_mode; /* output */ 1268 __u64 feature_flags; /* output */ 1269 __u32 xdp_zc_max_segs; /* output */ 1270 size_t :0; 1271 }; 1272 #define bpf_xdp_query_opts__last_field xdp_zc_max_segs 1273 1274 LIBBPF_API int bpf_xdp_attach(int ifindex, int prog_fd, __u32 flags, 1275 const struct bpf_xdp_attach_opts *opts); 1276 LIBBPF_API int bpf_xdp_detach(int ifindex, __u32 flags, 1277 const struct bpf_xdp_attach_opts *opts); 1278 LIBBPF_API int bpf_xdp_query(int ifindex, int flags, struct bpf_xdp_query_opts *opts); 1279 LIBBPF_API int bpf_xdp_query_id(int ifindex, int flags, __u32 *prog_id); 1280 1281 /* TC related API */ 1282 enum bpf_tc_attach_point { 1283 BPF_TC_INGRESS = 1 << 0, 1284 BPF_TC_EGRESS = 1 << 1, 1285 BPF_TC_CUSTOM = 1 << 2, 1286 BPF_TC_QDISC = 1 << 3, 1287 }; 1288 1289 #define BPF_TC_PARENT(a, b) \ 1290 ((((a) << 16) & 0xFFFF0000U) | ((b) & 0x0000FFFFU)) 1291 1292 enum bpf_tc_flags { 1293 BPF_TC_F_REPLACE = 1 << 0, 1294 }; 1295 1296 struct bpf_tc_hook { 1297 size_t sz; 1298 int ifindex; 1299 enum bpf_tc_attach_point attach_point; 1300 __u32 parent; 1301 __u32 handle; 1302 const char *qdisc; 1303 size_t :0; 1304 }; 1305 #define bpf_tc_hook__last_field qdisc 1306 1307 struct bpf_tc_opts { 1308 size_t sz; 1309 int prog_fd; 1310 __u32 flags; 1311 __u32 prog_id; 1312 __u32 handle; 1313 __u32 priority; 1314 size_t :0; 1315 }; 1316 #define bpf_tc_opts__last_field priority 1317 1318 LIBBPF_API int bpf_tc_hook_create(struct bpf_tc_hook *hook); 1319 LIBBPF_API int bpf_tc_hook_destroy(struct bpf_tc_hook *hook); 1320 LIBBPF_API int bpf_tc_attach(const struct bpf_tc_hook *hook, 1321 struct bpf_tc_opts *opts); 1322 LIBBPF_API int bpf_tc_detach(const struct bpf_tc_hook *hook, 1323 const struct bpf_tc_opts *opts); 1324 LIBBPF_API int bpf_tc_query(const struct bpf_tc_hook *hook, 1325 struct bpf_tc_opts *opts); 1326 1327 /* Ring buffer APIs */ 1328 struct ring_buffer; 1329 struct ring; 1330 struct user_ring_buffer; 1331 1332 typedef int (*ring_buffer_sample_fn)(void *ctx, void *data, size_t size); 1333 1334 struct ring_buffer_opts { 1335 size_t sz; /* size of this struct, for forward/backward compatibility */ 1336 }; 1337 1338 #define ring_buffer_opts__last_field sz 1339 1340 LIBBPF_API struct ring_buffer * 1341 ring_buffer__new(int map_fd, ring_buffer_sample_fn sample_cb, void *ctx, 1342 const struct ring_buffer_opts *opts); 1343 LIBBPF_API void ring_buffer__free(struct ring_buffer *rb); 1344 LIBBPF_API int ring_buffer__add(struct ring_buffer *rb, int map_fd, 1345 ring_buffer_sample_fn sample_cb, void *ctx); 1346 LIBBPF_API int ring_buffer__poll(struct ring_buffer *rb, int timeout_ms); 1347 LIBBPF_API int ring_buffer__consume(struct ring_buffer *rb); 1348 LIBBPF_API int ring_buffer__consume_n(struct ring_buffer *rb, size_t n); 1349 LIBBPF_API int ring_buffer__epoll_fd(const struct ring_buffer *rb); 1350 1351 /** 1352 * @brief **ring_buffer__ring()** returns the ringbuffer object inside a given 1353 * ringbuffer manager representing a single BPF_MAP_TYPE_RINGBUF map instance. 1354 * 1355 * @param rb A ringbuffer manager object. 1356 * @param idx An index into the ringbuffers contained within the ringbuffer 1357 * manager object. The index is 0-based and corresponds to the order in which 1358 * ring_buffer__add was called. 1359 * @return A ringbuffer object on success; NULL and errno set if the index is 1360 * invalid. 1361 */ 1362 LIBBPF_API struct ring *ring_buffer__ring(struct ring_buffer *rb, 1363 unsigned int idx); 1364 1365 /** 1366 * @brief **ring__consumer_pos()** returns the current consumer position in the 1367 * given ringbuffer. 1368 * 1369 * @param r A ringbuffer object. 1370 * @return The current consumer position. 1371 */ 1372 LIBBPF_API unsigned long ring__consumer_pos(const struct ring *r); 1373 1374 /** 1375 * @brief **ring__producer_pos()** returns the current producer position in the 1376 * given ringbuffer. 1377 * 1378 * @param r A ringbuffer object. 1379 * @return The current producer position. 1380 */ 1381 LIBBPF_API unsigned long ring__producer_pos(const struct ring *r); 1382 1383 /** 1384 * @brief **ring__avail_data_size()** returns the number of bytes in the 1385 * ringbuffer not yet consumed. This has no locking associated with it, so it 1386 * can be inaccurate if operations are ongoing while this is called. However, it 1387 * should still show the correct trend over the long-term. 1388 * 1389 * @param r A ringbuffer object. 1390 * @return The number of bytes not yet consumed. 1391 */ 1392 LIBBPF_API size_t ring__avail_data_size(const struct ring *r); 1393 1394 /** 1395 * @brief **ring__size()** returns the total size of the ringbuffer's map data 1396 * area (excluding special producer/consumer pages). Effectively this gives the 1397 * amount of usable bytes of data inside the ringbuffer. 1398 * 1399 * @param r A ringbuffer object. 1400 * @return The total size of the ringbuffer map data area. 1401 */ 1402 LIBBPF_API size_t ring__size(const struct ring *r); 1403 1404 /** 1405 * @brief **ring__map_fd()** returns the file descriptor underlying the given 1406 * ringbuffer. 1407 * 1408 * @param r A ringbuffer object. 1409 * @return The underlying ringbuffer file descriptor 1410 */ 1411 LIBBPF_API int ring__map_fd(const struct ring *r); 1412 1413 /** 1414 * @brief **ring__consume()** consumes available ringbuffer data without event 1415 * polling. 1416 * 1417 * @param r A ringbuffer object. 1418 * @return The number of records consumed (or INT_MAX, whichever is less), or 1419 * a negative number if any of the callbacks return an error. 1420 */ 1421 LIBBPF_API int ring__consume(struct ring *r); 1422 1423 /** 1424 * @brief **ring__consume_n()** consumes up to a requested amount of items from 1425 * a ringbuffer without event polling. 1426 * 1427 * @param r A ringbuffer object. 1428 * @param n Maximum amount of items to consume. 1429 * @return The number of items consumed, or a negative number if any of the 1430 * callbacks return an error. 1431 */ 1432 LIBBPF_API int ring__consume_n(struct ring *r, size_t n); 1433 1434 struct user_ring_buffer_opts { 1435 size_t sz; /* size of this struct, for forward/backward compatibility */ 1436 }; 1437 1438 #define user_ring_buffer_opts__last_field sz 1439 1440 /** 1441 * @brief **user_ring_buffer__new()** creates a new instance of a user ring 1442 * buffer. 1443 * 1444 * @param map_fd A file descriptor to a BPF_MAP_TYPE_USER_RINGBUF map. 1445 * @param opts Options for how the ring buffer should be created. 1446 * @return A user ring buffer on success; NULL and errno being set on a 1447 * failure. 1448 */ 1449 LIBBPF_API struct user_ring_buffer * 1450 user_ring_buffer__new(int map_fd, const struct user_ring_buffer_opts *opts); 1451 1452 /** 1453 * @brief **user_ring_buffer__reserve()** reserves a pointer to a sample in the 1454 * user ring buffer. 1455 * @param rb A pointer to a user ring buffer. 1456 * @param size The size of the sample, in bytes. 1457 * @return A pointer to an 8-byte aligned reserved region of the user ring 1458 * buffer; NULL, and errno being set if a sample could not be reserved. 1459 * 1460 * This function is *not* thread safe, and callers must synchronize accessing 1461 * this function if there are multiple producers. If a size is requested that 1462 * is larger than the size of the entire ring buffer, errno will be set to 1463 * E2BIG and NULL is returned. If the ring buffer could accommodate the size, 1464 * but currently does not have enough space, errno is set to ENOSPC and NULL is 1465 * returned. 1466 * 1467 * After initializing the sample, callers must invoke 1468 * **user_ring_buffer__submit()** to post the sample to the kernel. Otherwise, 1469 * the sample must be freed with **user_ring_buffer__discard()**. 1470 */ 1471 LIBBPF_API void *user_ring_buffer__reserve(struct user_ring_buffer *rb, __u32 size); 1472 1473 /** 1474 * @brief **user_ring_buffer__reserve_blocking()** reserves a record in the 1475 * ring buffer, possibly blocking for up to @timeout_ms until a sample becomes 1476 * available. 1477 * @param rb The user ring buffer. 1478 * @param size The size of the sample, in bytes. 1479 * @param timeout_ms The amount of time, in milliseconds, for which the caller 1480 * should block when waiting for a sample. -1 causes the caller to block 1481 * indefinitely. 1482 * @return A pointer to an 8-byte aligned reserved region of the user ring 1483 * buffer; NULL, and errno being set if a sample could not be reserved. 1484 * 1485 * This function is *not* thread safe, and callers must synchronize 1486 * accessing this function if there are multiple producers 1487 * 1488 * If **timeout_ms** is -1, the function will block indefinitely until a sample 1489 * becomes available. Otherwise, **timeout_ms** must be non-negative, or errno 1490 * is set to EINVAL, and NULL is returned. If **timeout_ms** is 0, no blocking 1491 * will occur and the function will return immediately after attempting to 1492 * reserve a sample. 1493 * 1494 * If **size** is larger than the size of the entire ring buffer, errno is set 1495 * to E2BIG and NULL is returned. If the ring buffer could accommodate 1496 * **size**, but currently does not have enough space, the caller will block 1497 * until at most **timeout_ms** has elapsed. If insufficient space is available 1498 * at that time, errno is set to ENOSPC, and NULL is returned. 1499 * 1500 * The kernel guarantees that it will wake up this thread to check if 1501 * sufficient space is available in the ring buffer at least once per 1502 * invocation of the **bpf_ringbuf_drain()** helper function, provided that at 1503 * least one sample is consumed, and the BPF program did not invoke the 1504 * function with BPF_RB_NO_WAKEUP. A wakeup may occur sooner than that, but the 1505 * kernel does not guarantee this. If the helper function is invoked with 1506 * BPF_RB_FORCE_WAKEUP, a wakeup event will be sent even if no sample is 1507 * consumed. 1508 * 1509 * When a sample of size **size** is found within **timeout_ms**, a pointer to 1510 * the sample is returned. After initializing the sample, callers must invoke 1511 * **user_ring_buffer__submit()** to post the sample to the ring buffer. 1512 * Otherwise, the sample must be freed with **user_ring_buffer__discard()**. 1513 */ 1514 LIBBPF_API void *user_ring_buffer__reserve_blocking(struct user_ring_buffer *rb, 1515 __u32 size, 1516 int timeout_ms); 1517 1518 /** 1519 * @brief **user_ring_buffer__submit()** submits a previously reserved sample 1520 * into the ring buffer. 1521 * @param rb The user ring buffer. 1522 * @param sample A reserved sample. 1523 * 1524 * It is not necessary to synchronize amongst multiple producers when invoking 1525 * this function. 1526 */ 1527 LIBBPF_API void user_ring_buffer__submit(struct user_ring_buffer *rb, void *sample); 1528 1529 /** 1530 * @brief **user_ring_buffer__discard()** discards a previously reserved sample. 1531 * @param rb The user ring buffer. 1532 * @param sample A reserved sample. 1533 * 1534 * It is not necessary to synchronize amongst multiple producers when invoking 1535 * this function. 1536 */ 1537 LIBBPF_API void user_ring_buffer__discard(struct user_ring_buffer *rb, void *sample); 1538 1539 /** 1540 * @brief **user_ring_buffer__free()** frees a ring buffer that was previously 1541 * created with **user_ring_buffer__new()**. 1542 * @param rb The user ring buffer being freed. 1543 */ 1544 LIBBPF_API void user_ring_buffer__free(struct user_ring_buffer *rb); 1545 1546 /* Perf buffer APIs */ 1547 struct perf_buffer; 1548 1549 typedef void (*perf_buffer_sample_fn)(void *ctx, int cpu, 1550 void *data, __u32 size); 1551 typedef void (*perf_buffer_lost_fn)(void *ctx, int cpu, __u64 cnt); 1552 1553 /* common use perf buffer options */ 1554 struct perf_buffer_opts { 1555 size_t sz; 1556 __u32 sample_period; 1557 size_t :0; 1558 }; 1559 #define perf_buffer_opts__last_field sample_period 1560 1561 /** 1562 * @brief **perf_buffer__new()** creates BPF perfbuf manager for a specified 1563 * BPF_PERF_EVENT_ARRAY map 1564 * @param map_fd FD of BPF_PERF_EVENT_ARRAY BPF map that will be used by BPF 1565 * code to send data over to user-space 1566 * @param page_cnt number of memory pages allocated for each per-CPU buffer 1567 * @param sample_cb function called on each received data record 1568 * @param lost_cb function called when record loss has occurred 1569 * @param ctx user-provided extra context passed into *sample_cb* and *lost_cb* 1570 * @return a new instance of struct perf_buffer on success, NULL on error with 1571 * *errno* containing an error code 1572 */ 1573 LIBBPF_API struct perf_buffer * 1574 perf_buffer__new(int map_fd, size_t page_cnt, 1575 perf_buffer_sample_fn sample_cb, perf_buffer_lost_fn lost_cb, void *ctx, 1576 const struct perf_buffer_opts *opts); 1577 1578 enum bpf_perf_event_ret { 1579 LIBBPF_PERF_EVENT_DONE = 0, 1580 LIBBPF_PERF_EVENT_ERROR = -1, 1581 LIBBPF_PERF_EVENT_CONT = -2, 1582 }; 1583 1584 struct perf_event_header; 1585 1586 typedef enum bpf_perf_event_ret 1587 (*perf_buffer_event_fn)(void *ctx, int cpu, struct perf_event_header *event); 1588 1589 /* raw perf buffer options, giving most power and control */ 1590 struct perf_buffer_raw_opts { 1591 size_t sz; 1592 long :0; 1593 long :0; 1594 /* if cpu_cnt == 0, open all on all possible CPUs (up to the number of 1595 * max_entries of given PERF_EVENT_ARRAY map) 1596 */ 1597 int cpu_cnt; 1598 /* if cpu_cnt > 0, cpus is an array of CPUs to open ring buffers on */ 1599 int *cpus; 1600 /* if cpu_cnt > 0, map_keys specify map keys to set per-CPU FDs for */ 1601 int *map_keys; 1602 }; 1603 #define perf_buffer_raw_opts__last_field map_keys 1604 1605 struct perf_event_attr; 1606 1607 LIBBPF_API struct perf_buffer * 1608 perf_buffer__new_raw(int map_fd, size_t page_cnt, struct perf_event_attr *attr, 1609 perf_buffer_event_fn event_cb, void *ctx, 1610 const struct perf_buffer_raw_opts *opts); 1611 1612 LIBBPF_API void perf_buffer__free(struct perf_buffer *pb); 1613 LIBBPF_API int perf_buffer__epoll_fd(const struct perf_buffer *pb); 1614 LIBBPF_API int perf_buffer__poll(struct perf_buffer *pb, int timeout_ms); 1615 LIBBPF_API int perf_buffer__consume(struct perf_buffer *pb); 1616 LIBBPF_API int perf_buffer__consume_buffer(struct perf_buffer *pb, size_t buf_idx); 1617 LIBBPF_API size_t perf_buffer__buffer_cnt(const struct perf_buffer *pb); 1618 LIBBPF_API int perf_buffer__buffer_fd(const struct perf_buffer *pb, size_t buf_idx); 1619 /** 1620 * @brief **perf_buffer__buffer()** returns the per-cpu raw mmap()'ed underlying 1621 * memory region of the ring buffer. 1622 * This ring buffer can be used to implement a custom events consumer. 1623 * The ring buffer starts with the *struct perf_event_mmap_page*, which 1624 * holds the ring buffer management fields, when accessing the header 1625 * structure it's important to be SMP aware. 1626 * You can refer to *perf_event_read_simple* for a simple example. 1627 * @param pb the perf buffer structure 1628 * @param buf_idx the buffer index to retrieve 1629 * @param buf (out) gets the base pointer of the mmap()'ed memory 1630 * @param buf_size (out) gets the size of the mmap()'ed region 1631 * @return 0 on success, negative error code for failure 1632 */ 1633 LIBBPF_API int perf_buffer__buffer(struct perf_buffer *pb, int buf_idx, void **buf, 1634 size_t *buf_size); 1635 1636 struct bpf_prog_linfo; 1637 struct bpf_prog_info; 1638 1639 LIBBPF_API void bpf_prog_linfo__free(struct bpf_prog_linfo *prog_linfo); 1640 LIBBPF_API struct bpf_prog_linfo * 1641 bpf_prog_linfo__new(const struct bpf_prog_info *info); 1642 LIBBPF_API const struct bpf_line_info * 1643 bpf_prog_linfo__lfind_addr_func(const struct bpf_prog_linfo *prog_linfo, 1644 __u64 addr, __u32 func_idx, __u32 nr_skip); 1645 LIBBPF_API const struct bpf_line_info * 1646 bpf_prog_linfo__lfind(const struct bpf_prog_linfo *prog_linfo, 1647 __u32 insn_off, __u32 nr_skip); 1648 1649 /* 1650 * Probe for supported system features 1651 * 1652 * Note that running many of these probes in a short amount of time can cause 1653 * the kernel to reach the maximal size of lockable memory allowed for the 1654 * user, causing subsequent probes to fail. In this case, the caller may want 1655 * to adjust that limit with setrlimit(). 1656 */ 1657 1658 /** 1659 * @brief **libbpf_probe_bpf_prog_type()** detects if host kernel supports 1660 * BPF programs of a given type. 1661 * @param prog_type BPF program type to detect kernel support for 1662 * @param opts reserved for future extensibility, should be NULL 1663 * @return 1, if given program type is supported; 0, if given program type is 1664 * not supported; negative error code if feature detection failed or can't be 1665 * performed 1666 * 1667 * Make sure the process has required set of CAP_* permissions (or runs as 1668 * root) when performing feature checking. 1669 */ 1670 LIBBPF_API int libbpf_probe_bpf_prog_type(enum bpf_prog_type prog_type, const void *opts); 1671 /** 1672 * @brief **libbpf_probe_bpf_map_type()** detects if host kernel supports 1673 * BPF maps of a given type. 1674 * @param map_type BPF map type to detect kernel support for 1675 * @param opts reserved for future extensibility, should be NULL 1676 * @return 1, if given map type is supported; 0, if given map type is 1677 * not supported; negative error code if feature detection failed or can't be 1678 * performed 1679 * 1680 * Make sure the process has required set of CAP_* permissions (or runs as 1681 * root) when performing feature checking. 1682 */ 1683 LIBBPF_API int libbpf_probe_bpf_map_type(enum bpf_map_type map_type, const void *opts); 1684 /** 1685 * @brief **libbpf_probe_bpf_helper()** detects if host kernel supports the 1686 * use of a given BPF helper from specified BPF program type. 1687 * @param prog_type BPF program type used to check the support of BPF helper 1688 * @param helper_id BPF helper ID (enum bpf_func_id) to check support for 1689 * @param opts reserved for future extensibility, should be NULL 1690 * @return 1, if given combination of program type and helper is supported; 0, 1691 * if the combination is not supported; negative error code if feature 1692 * detection for provided input arguments failed or can't be performed 1693 * 1694 * Make sure the process has required set of CAP_* permissions (or runs as 1695 * root) when performing feature checking. 1696 */ 1697 LIBBPF_API int libbpf_probe_bpf_helper(enum bpf_prog_type prog_type, 1698 enum bpf_func_id helper_id, const void *opts); 1699 1700 /** 1701 * @brief **libbpf_num_possible_cpus()** is a helper function to get the 1702 * number of possible CPUs that the host kernel supports and expects. 1703 * @return number of possible CPUs; or error code on failure 1704 * 1705 * Example usage: 1706 * 1707 * int ncpus = libbpf_num_possible_cpus(); 1708 * if (ncpus < 0) { 1709 * // error handling 1710 * } 1711 * long values[ncpus]; 1712 * bpf_map_lookup_elem(per_cpu_map_fd, key, values); 1713 */ 1714 LIBBPF_API int libbpf_num_possible_cpus(void); 1715 1716 struct bpf_map_skeleton { 1717 const char *name; 1718 struct bpf_map **map; 1719 void **mmaped; 1720 struct bpf_link **link; 1721 }; 1722 1723 struct bpf_prog_skeleton { 1724 const char *name; 1725 struct bpf_program **prog; 1726 struct bpf_link **link; 1727 }; 1728 1729 struct bpf_object_skeleton { 1730 size_t sz; /* size of this struct, for forward/backward compatibility */ 1731 1732 const char *name; 1733 const void *data; 1734 size_t data_sz; 1735 1736 struct bpf_object **obj; 1737 1738 int map_cnt; 1739 int map_skel_sz; /* sizeof(struct bpf_map_skeleton) */ 1740 struct bpf_map_skeleton *maps; 1741 1742 int prog_cnt; 1743 int prog_skel_sz; /* sizeof(struct bpf_prog_skeleton) */ 1744 struct bpf_prog_skeleton *progs; 1745 }; 1746 1747 LIBBPF_API int 1748 bpf_object__open_skeleton(struct bpf_object_skeleton *s, 1749 const struct bpf_object_open_opts *opts); 1750 LIBBPF_API int bpf_object__load_skeleton(struct bpf_object_skeleton *s); 1751 LIBBPF_API int bpf_object__attach_skeleton(struct bpf_object_skeleton *s); 1752 LIBBPF_API void bpf_object__detach_skeleton(struct bpf_object_skeleton *s); 1753 LIBBPF_API void bpf_object__destroy_skeleton(struct bpf_object_skeleton *s); 1754 1755 struct bpf_var_skeleton { 1756 const char *name; 1757 struct bpf_map **map; 1758 void **addr; 1759 }; 1760 1761 struct bpf_object_subskeleton { 1762 size_t sz; /* size of this struct, for forward/backward compatibility */ 1763 1764 const struct bpf_object *obj; 1765 1766 int map_cnt; 1767 int map_skel_sz; /* sizeof(struct bpf_map_skeleton) */ 1768 struct bpf_map_skeleton *maps; 1769 1770 int prog_cnt; 1771 int prog_skel_sz; /* sizeof(struct bpf_prog_skeleton) */ 1772 struct bpf_prog_skeleton *progs; 1773 1774 int var_cnt; 1775 int var_skel_sz; /* sizeof(struct bpf_var_skeleton) */ 1776 struct bpf_var_skeleton *vars; 1777 }; 1778 1779 LIBBPF_API int 1780 bpf_object__open_subskeleton(struct bpf_object_subskeleton *s); 1781 LIBBPF_API void 1782 bpf_object__destroy_subskeleton(struct bpf_object_subskeleton *s); 1783 1784 struct gen_loader_opts { 1785 size_t sz; /* size of this struct, for forward/backward compatibility */ 1786 const char *data; 1787 const char *insns; 1788 __u32 data_sz; 1789 __u32 insns_sz; 1790 }; 1791 1792 #define gen_loader_opts__last_field insns_sz 1793 LIBBPF_API int bpf_object__gen_loader(struct bpf_object *obj, 1794 struct gen_loader_opts *opts); 1795 1796 enum libbpf_tristate { 1797 TRI_NO = 0, 1798 TRI_YES = 1, 1799 TRI_MODULE = 2, 1800 }; 1801 1802 struct bpf_linker_opts { 1803 /* size of this struct, for forward/backward compatibility */ 1804 size_t sz; 1805 }; 1806 #define bpf_linker_opts__last_field sz 1807 1808 struct bpf_linker_file_opts { 1809 /* size of this struct, for forward/backward compatibility */ 1810 size_t sz; 1811 }; 1812 #define bpf_linker_file_opts__last_field sz 1813 1814 struct bpf_linker; 1815 1816 LIBBPF_API struct bpf_linker *bpf_linker__new(const char *filename, struct bpf_linker_opts *opts); 1817 LIBBPF_API struct bpf_linker *bpf_linker__new_fd(int fd, struct bpf_linker_opts *opts); 1818 LIBBPF_API int bpf_linker__add_file(struct bpf_linker *linker, 1819 const char *filename, 1820 const struct bpf_linker_file_opts *opts); 1821 LIBBPF_API int bpf_linker__add_fd(struct bpf_linker *linker, int fd, 1822 const struct bpf_linker_file_opts *opts); 1823 LIBBPF_API int bpf_linker__add_buf(struct bpf_linker *linker, void *buf, size_t buf_sz, 1824 const struct bpf_linker_file_opts *opts); 1825 LIBBPF_API int bpf_linker__finalize(struct bpf_linker *linker); 1826 LIBBPF_API void bpf_linker__free(struct bpf_linker *linker); 1827 1828 /* 1829 * Custom handling of BPF program's SEC() definitions 1830 */ 1831 1832 struct bpf_prog_load_opts; /* defined in bpf.h */ 1833 1834 /* Called during bpf_object__open() for each recognized BPF program. Callback 1835 * can use various bpf_program__set_*() setters to adjust whatever properties 1836 * are necessary. 1837 */ 1838 typedef int (*libbpf_prog_setup_fn_t)(struct bpf_program *prog, long cookie); 1839 1840 /* Called right before libbpf performs bpf_prog_load() to load BPF program 1841 * into the kernel. Callback can adjust opts as necessary. 1842 */ 1843 typedef int (*libbpf_prog_prepare_load_fn_t)(struct bpf_program *prog, 1844 struct bpf_prog_load_opts *opts, long cookie); 1845 1846 /* Called during skeleton attach or through bpf_program__attach(). If 1847 * auto-attach is not supported, callback should return 0 and set link to 1848 * NULL (it's not considered an error during skeleton attach, but it will be 1849 * an error for bpf_program__attach() calls). On error, error should be 1850 * returned directly and link set to NULL. On success, return 0 and set link 1851 * to a valid struct bpf_link. 1852 */ 1853 typedef int (*libbpf_prog_attach_fn_t)(const struct bpf_program *prog, long cookie, 1854 struct bpf_link **link); 1855 1856 struct libbpf_prog_handler_opts { 1857 /* size of this struct, for forward/backward compatibility */ 1858 size_t sz; 1859 /* User-provided value that is passed to prog_setup_fn, 1860 * prog_prepare_load_fn, and prog_attach_fn callbacks. Allows user to 1861 * register one set of callbacks for multiple SEC() definitions and 1862 * still be able to distinguish them, if necessary. For example, 1863 * libbpf itself is using this to pass necessary flags (e.g., 1864 * sleepable flag) to a common internal SEC() handler. 1865 */ 1866 long cookie; 1867 /* BPF program initialization callback (see libbpf_prog_setup_fn_t). 1868 * Callback is optional, pass NULL if it's not necessary. 1869 */ 1870 libbpf_prog_setup_fn_t prog_setup_fn; 1871 /* BPF program loading callback (see libbpf_prog_prepare_load_fn_t). 1872 * Callback is optional, pass NULL if it's not necessary. 1873 */ 1874 libbpf_prog_prepare_load_fn_t prog_prepare_load_fn; 1875 /* BPF program attach callback (see libbpf_prog_attach_fn_t). 1876 * Callback is optional, pass NULL if it's not necessary. 1877 */ 1878 libbpf_prog_attach_fn_t prog_attach_fn; 1879 }; 1880 #define libbpf_prog_handler_opts__last_field prog_attach_fn 1881 1882 /** 1883 * @brief **libbpf_register_prog_handler()** registers a custom BPF program 1884 * SEC() handler. 1885 * @param sec section prefix for which custom handler is registered 1886 * @param prog_type BPF program type associated with specified section 1887 * @param exp_attach_type Expected BPF attach type associated with specified section 1888 * @param opts optional cookie, callbacks, and other extra options 1889 * @return Non-negative handler ID is returned on success. This handler ID has 1890 * to be passed to *libbpf_unregister_prog_handler()* to unregister such 1891 * custom handler. Negative error code is returned on error. 1892 * 1893 * *sec* defines which SEC() definitions are handled by this custom handler 1894 * registration. *sec* can have few different forms: 1895 * - if *sec* is just a plain string (e.g., "abc"), it will match only 1896 * SEC("abc"). If BPF program specifies SEC("abc/whatever") it will result 1897 * in an error; 1898 * - if *sec* is of the form "abc/", proper SEC() form is 1899 * SEC("abc/something"), where acceptable "something" should be checked by 1900 * *prog_init_fn* callback, if there are additional restrictions; 1901 * - if *sec* is of the form "abc+", it will successfully match both 1902 * SEC("abc") and SEC("abc/whatever") forms; 1903 * - if *sec* is NULL, custom handler is registered for any BPF program that 1904 * doesn't match any of the registered (custom or libbpf's own) SEC() 1905 * handlers. There could be only one such generic custom handler registered 1906 * at any given time. 1907 * 1908 * All custom handlers (except the one with *sec* == NULL) are processed 1909 * before libbpf's own SEC() handlers. It is allowed to "override" libbpf's 1910 * SEC() handlers by registering custom ones for the same section prefix 1911 * (i.e., it's possible to have custom SEC("perf_event/LLC-load-misses") 1912 * handler). 1913 * 1914 * Note, like much of global libbpf APIs (e.g., libbpf_set_print(), 1915 * libbpf_set_strict_mode(), etc)) these APIs are not thread-safe. User needs 1916 * to ensure synchronization if there is a risk of running this API from 1917 * multiple threads simultaneously. 1918 */ 1919 LIBBPF_API int libbpf_register_prog_handler(const char *sec, 1920 enum bpf_prog_type prog_type, 1921 enum bpf_attach_type exp_attach_type, 1922 const struct libbpf_prog_handler_opts *opts); 1923 /** 1924 * @brief *libbpf_unregister_prog_handler()* unregisters previously registered 1925 * custom BPF program SEC() handler. 1926 * @param handler_id handler ID returned by *libbpf_register_prog_handler()* 1927 * after successful registration 1928 * @return 0 on success, negative error code if handler isn't found 1929 * 1930 * Note, like much of global libbpf APIs (e.g., libbpf_set_print(), 1931 * libbpf_set_strict_mode(), etc)) these APIs are not thread-safe. User needs 1932 * to ensure synchronization if there is a risk of running this API from 1933 * multiple threads simultaneously. 1934 */ 1935 LIBBPF_API int libbpf_unregister_prog_handler(int handler_id); 1936 1937 #ifdef __cplusplus 1938 } /* extern "C" */ 1939 #endif 1940 1941 #endif /* __LIBBPF_LIBBPF_H */ 1942