1 // SPDX-License-Identifier: LGPL-2.1
4 * Common eBPF ELF object loading operations.
6 * Copyright (C) 2013-2015 Alexei Starovoitov <ast@kernel.org>
7 * Copyright (C) 2015 Wang Nan <wangnan0@huawei.com>
8 * Copyright (C) 2015 Huawei Inc.
9 * Copyright (C) 2017 Nicira, Inc.
11 * This program is free software; you can redistribute it and/or
12 * modify it under the terms of the GNU Lesser General Public
13 * License as published by the Free Software Foundation;
14 * version 2.1 of the License (not later!)
16 * This program is distributed in the hope that it will be useful,
17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 * GNU Lesser General Public License for more details.
21 * You should have received a copy of the GNU Lesser General Public
22 * License along with this program; if not, see <http://www.gnu.org/licenses>
36 #include <asm/unistd.h>
37 #include <linux/err.h>
38 #include <linux/kernel.h>
39 #include <linux/bpf.h>
40 #include <linux/btf.h>
41 #include <linux/list.h>
42 #include <linux/limits.h>
44 #include <sys/types.h>
46 #include <tools/libc_compat.h>
53 #include "str_error.h"
60 #define BPF_FS_MAGIC 0xcafe4a11
63 #define __printf(a, b) __attribute__((format(printf, a, b)))
66 static int __base_pr(const char *format, ...)
71 va_start(args, format);
72 err = vfprintf(stderr, format, args);
77 static __printf(1, 2) libbpf_print_fn_t __pr_warning = __base_pr;
78 static __printf(1, 2) libbpf_print_fn_t __pr_info = __base_pr;
79 static __printf(1, 2) libbpf_print_fn_t __pr_debug;
81 #define __pr(func, fmt, ...) \
84 (func)("libbpf: " fmt, ##__VA_ARGS__); \
87 #define pr_warning(fmt, ...) __pr(__pr_warning, fmt, ##__VA_ARGS__)
88 #define pr_info(fmt, ...) __pr(__pr_info, fmt, ##__VA_ARGS__)
89 #define pr_debug(fmt, ...) __pr(__pr_debug, fmt, ##__VA_ARGS__)
91 void libbpf_set_print(libbpf_print_fn_t warn,
92 libbpf_print_fn_t info,
93 libbpf_print_fn_t debug)
100 #define STRERR_BUFSIZE 128
102 #define CHECK_ERR(action, err, out) do { \
109 /* Copied from tools/perf/util/util.h */
111 # define zfree(ptr) ({ free(*ptr); *ptr = NULL; })
115 # define zclose(fd) ({ \
118 ___err = close((fd)); \
123 #ifdef HAVE_LIBELF_MMAP_SUPPORT
124 # define LIBBPF_ELF_C_READ_MMAP ELF_C_READ_MMAP
126 # define LIBBPF_ELF_C_READ_MMAP ELF_C_READ
130 * bpf_prog should be a better name but it has been used in
134 /* Index in elf obj file, for relocation use. */
139 struct bpf_insn *insns;
140 size_t insns_cnt, main_prog_cnt;
141 enum bpf_prog_type type;
160 bpf_program_prep_t preprocessor;
162 struct bpf_object *obj;
164 bpf_program_clear_priv_t clear_priv;
166 enum bpf_attach_type expected_attach_type;
174 struct bpf_map_def def;
175 __u32 btf_key_type_id;
176 __u32 btf_value_type_id;
178 bpf_map_clear_priv_t clear_priv;
181 static LIST_HEAD(bpf_objects_list);
187 struct bpf_program *programs;
189 struct bpf_map *maps;
193 bool has_pseudo_calls;
196 * Information when doing elf related work. Only valid if fd
216 * All loaded bpf_object is linked in a list, which is
217 * hidden to caller. bpf_objects__<func> handlers deal with
220 struct list_head list;
225 bpf_object_clear_priv_t clear_priv;
229 #define obj_elf_valid(o) ((o)->efile.elf)
231 void bpf_program__unload(struct bpf_program *prog)
239 * If the object is opened but the program was never loaded,
240 * it is possible that prog->instances.nr == -1.
242 if (prog->instances.nr > 0) {
243 for (i = 0; i < prog->instances.nr; i++)
244 zclose(prog->instances.fds[i]);
245 } else if (prog->instances.nr != -1) {
246 pr_warning("Internal error: instances.nr is %d\n",
250 prog->instances.nr = -1;
251 zfree(&prog->instances.fds);
254 static void bpf_program__exit(struct bpf_program *prog)
259 if (prog->clear_priv)
260 prog->clear_priv(prog, prog->priv);
263 prog->clear_priv = NULL;
265 bpf_program__unload(prog);
267 zfree(&prog->section_name);
269 zfree(&prog->reloc_desc);
277 bpf_program__init(void *data, size_t size, char *section_name, int idx,
278 struct bpf_program *prog)
280 if (size < sizeof(struct bpf_insn)) {
281 pr_warning("corrupted section '%s'\n", section_name);
285 bzero(prog, sizeof(*prog));
287 prog->section_name = strdup(section_name);
288 if (!prog->section_name) {
289 pr_warning("failed to alloc name for prog under section(%d) %s\n",
294 prog->insns = malloc(size);
296 pr_warning("failed to alloc insns for prog under section %s\n",
300 prog->insns_cnt = size / sizeof(struct bpf_insn);
301 memcpy(prog->insns, data,
302 prog->insns_cnt * sizeof(struct bpf_insn));
304 prog->instances.fds = NULL;
305 prog->instances.nr = -1;
306 prog->type = BPF_PROG_TYPE_KPROBE;
310 bpf_program__exit(prog);
315 bpf_object__add_program(struct bpf_object *obj, void *data, size_t size,
316 char *section_name, int idx)
318 struct bpf_program prog, *progs;
321 err = bpf_program__init(data, size, section_name, idx, &prog);
325 progs = obj->programs;
326 nr_progs = obj->nr_programs;
328 progs = reallocarray(progs, nr_progs + 1, sizeof(progs[0]));
331 * In this case the original obj->programs
332 * is still valid, so don't need special treat for
333 * bpf_close_object().
335 pr_warning("failed to alloc a new program under section '%s'\n",
337 bpf_program__exit(&prog);
341 pr_debug("found program %s\n", prog.section_name);
342 obj->programs = progs;
343 obj->nr_programs = nr_progs + 1;
345 progs[nr_progs] = prog;
350 bpf_object__init_prog_names(struct bpf_object *obj)
352 Elf_Data *symbols = obj->efile.symbols;
353 struct bpf_program *prog;
356 for (pi = 0; pi < obj->nr_programs; pi++) {
357 const char *name = NULL;
359 prog = &obj->programs[pi];
361 for (si = 0; si < symbols->d_size / sizeof(GElf_Sym) && !name;
365 if (!gelf_getsym(symbols, si, &sym))
367 if (sym.st_shndx != prog->idx)
369 if (GELF_ST_BIND(sym.st_info) != STB_GLOBAL)
372 name = elf_strptr(obj->efile.elf,
373 obj->efile.strtabidx,
376 pr_warning("failed to get sym name string for prog %s\n",
378 return -LIBBPF_ERRNO__LIBELF;
382 if (!name && prog->idx == obj->efile.text_shndx)
386 pr_warning("failed to find sym for prog %s\n",
391 prog->name = strdup(name);
393 pr_warning("failed to allocate memory for prog sym %s\n",
402 static struct bpf_object *bpf_object__new(const char *path,
406 struct bpf_object *obj;
408 obj = calloc(1, sizeof(struct bpf_object) + strlen(path) + 1);
410 pr_warning("alloc memory failed for %s\n", path);
411 return ERR_PTR(-ENOMEM);
414 strcpy(obj->path, path);
418 * Caller of this function should also calls
419 * bpf_object__elf_finish() after data collection to return
420 * obj_buf to user. If not, we should duplicate the buffer to
421 * avoid user freeing them before elf finish.
423 obj->efile.obj_buf = obj_buf;
424 obj->efile.obj_buf_sz = obj_buf_sz;
425 obj->efile.maps_shndx = -1;
429 INIT_LIST_HEAD(&obj->list);
430 list_add(&obj->list, &bpf_objects_list);
434 static void bpf_object__elf_finish(struct bpf_object *obj)
436 if (!obj_elf_valid(obj))
439 if (obj->efile.elf) {
440 elf_end(obj->efile.elf);
441 obj->efile.elf = NULL;
443 obj->efile.symbols = NULL;
445 zfree(&obj->efile.reloc);
446 obj->efile.nr_reloc = 0;
447 zclose(obj->efile.fd);
448 obj->efile.obj_buf = NULL;
449 obj->efile.obj_buf_sz = 0;
452 static int bpf_object__elf_init(struct bpf_object *obj)
457 if (obj_elf_valid(obj)) {
458 pr_warning("elf init: internal error\n");
459 return -LIBBPF_ERRNO__LIBELF;
462 if (obj->efile.obj_buf_sz > 0) {
464 * obj_buf should have been validated by
465 * bpf_object__open_buffer().
467 obj->efile.elf = elf_memory(obj->efile.obj_buf,
468 obj->efile.obj_buf_sz);
470 obj->efile.fd = open(obj->path, O_RDONLY);
471 if (obj->efile.fd < 0) {
472 char errmsg[STRERR_BUFSIZE];
473 char *cp = libbpf_strerror_r(errno, errmsg,
476 pr_warning("failed to open %s: %s\n", obj->path, cp);
480 obj->efile.elf = elf_begin(obj->efile.fd,
481 LIBBPF_ELF_C_READ_MMAP,
485 if (!obj->efile.elf) {
486 pr_warning("failed to open %s as ELF file\n",
488 err = -LIBBPF_ERRNO__LIBELF;
492 if (!gelf_getehdr(obj->efile.elf, &obj->efile.ehdr)) {
493 pr_warning("failed to get EHDR from %s\n",
495 err = -LIBBPF_ERRNO__FORMAT;
498 ep = &obj->efile.ehdr;
500 /* Old LLVM set e_machine to EM_NONE */
501 if ((ep->e_type != ET_REL) || (ep->e_machine && (ep->e_machine != EM_BPF))) {
502 pr_warning("%s is not an eBPF object file\n",
504 err = -LIBBPF_ERRNO__FORMAT;
510 bpf_object__elf_finish(obj);
515 bpf_object__check_endianness(struct bpf_object *obj)
517 static unsigned int const endian = 1;
519 switch (obj->efile.ehdr.e_ident[EI_DATA]) {
521 /* We are big endian, BPF obj is little endian. */
522 if (*(unsigned char const *)&endian != 1)
527 /* We are little endian, BPF obj is big endian. */
528 if (*(unsigned char const *)&endian != 0)
532 return -LIBBPF_ERRNO__ENDIAN;
538 pr_warning("Error: endianness mismatch.\n");
539 return -LIBBPF_ERRNO__ENDIAN;
543 bpf_object__init_license(struct bpf_object *obj,
544 void *data, size_t size)
546 memcpy(obj->license, data,
547 min(size, sizeof(obj->license) - 1));
548 pr_debug("license of %s is %s\n", obj->path, obj->license);
553 bpf_object__init_kversion(struct bpf_object *obj,
554 void *data, size_t size)
558 if (size != sizeof(kver)) {
559 pr_warning("invalid kver section in %s\n", obj->path);
560 return -LIBBPF_ERRNO__FORMAT;
562 memcpy(&kver, data, sizeof(kver));
563 obj->kern_version = kver;
564 pr_debug("kernel version of %s is %x\n", obj->path,
569 static int compare_bpf_map(const void *_a, const void *_b)
571 const struct bpf_map *a = _a;
572 const struct bpf_map *b = _b;
574 return a->offset - b->offset;
578 bpf_object__init_maps(struct bpf_object *obj)
580 int i, map_idx, map_def_sz, nr_maps = 0;
583 Elf_Data *symbols = obj->efile.symbols;
585 if (obj->efile.maps_shndx < 0)
590 scn = elf_getscn(obj->efile.elf, obj->efile.maps_shndx);
592 data = elf_getdata(scn, NULL);
594 pr_warning("failed to get Elf_Data from map section %d\n",
595 obj->efile.maps_shndx);
600 * Count number of maps. Each map has a name.
601 * Array of maps is not supported: only the first element is
604 * TODO: Detect array of map and report error.
606 for (i = 0; i < symbols->d_size / sizeof(GElf_Sym); i++) {
609 if (!gelf_getsym(symbols, i, &sym))
611 if (sym.st_shndx != obj->efile.maps_shndx)
616 /* Alloc obj->maps and fill nr_maps. */
617 pr_debug("maps in %s: %d maps in %zd bytes\n", obj->path,
618 nr_maps, data->d_size);
623 /* Assume equally sized map definitions */
624 map_def_sz = data->d_size / nr_maps;
625 if (!data->d_size || (data->d_size % nr_maps) != 0) {
626 pr_warning("unable to determine map definition size "
627 "section %s, %d maps in %zd bytes\n",
628 obj->path, nr_maps, data->d_size);
632 obj->maps = calloc(nr_maps, sizeof(obj->maps[0]));
634 pr_warning("alloc maps for object failed\n");
637 obj->nr_maps = nr_maps;
640 * fill all fd with -1 so won't close incorrect
641 * fd (fd=0 is stdin) when failure (zclose won't close
644 for (i = 0; i < nr_maps; i++)
645 obj->maps[i].fd = -1;
648 * Fill obj->maps using data in "maps" section.
650 for (i = 0, map_idx = 0; i < symbols->d_size / sizeof(GElf_Sym); i++) {
652 const char *map_name;
653 struct bpf_map_def *def;
655 if (!gelf_getsym(symbols, i, &sym))
657 if (sym.st_shndx != obj->efile.maps_shndx)
660 map_name = elf_strptr(obj->efile.elf,
661 obj->efile.strtabidx,
663 obj->maps[map_idx].offset = sym.st_value;
664 if (sym.st_value + map_def_sz > data->d_size) {
665 pr_warning("corrupted maps section in %s: last map \"%s\" too small\n",
666 obj->path, map_name);
670 obj->maps[map_idx].name = strdup(map_name);
671 if (!obj->maps[map_idx].name) {
672 pr_warning("failed to alloc map name\n");
675 pr_debug("map %d is \"%s\"\n", map_idx,
676 obj->maps[map_idx].name);
677 def = (struct bpf_map_def *)(data->d_buf + sym.st_value);
679 * If the definition of the map in the object file fits in
680 * bpf_map_def, copy it. Any extra fields in our version
681 * of bpf_map_def will default to zero as a result of the
684 if (map_def_sz <= sizeof(struct bpf_map_def)) {
685 memcpy(&obj->maps[map_idx].def, def, map_def_sz);
688 * Here the map structure being read is bigger than what
689 * we expect, truncate if the excess bits are all zero.
690 * If they are not zero, reject this map as
694 for (b = ((char *)def) + sizeof(struct bpf_map_def);
695 b < ((char *)def) + map_def_sz; b++) {
697 pr_warning("maps section in %s: \"%s\" "
698 "has unrecognized, non-zero "
700 obj->path, map_name);
704 memcpy(&obj->maps[map_idx].def, def,
705 sizeof(struct bpf_map_def));
710 qsort(obj->maps, obj->nr_maps, sizeof(obj->maps[0]), compare_bpf_map);
714 static bool section_have_execinstr(struct bpf_object *obj, int idx)
719 scn = elf_getscn(obj->efile.elf, idx);
723 if (gelf_getshdr(scn, &sh) != &sh)
726 if (sh.sh_flags & SHF_EXECINSTR)
732 static int bpf_object__elf_collect(struct bpf_object *obj)
734 Elf *elf = obj->efile.elf;
735 GElf_Ehdr *ep = &obj->efile.ehdr;
737 int idx = 0, err = 0;
739 /* Elf is corrupted/truncated, avoid calling elf_strptr. */
740 if (!elf_rawdata(elf_getscn(elf, ep->e_shstrndx), NULL)) {
741 pr_warning("failed to get e_shstrndx from %s\n",
743 return -LIBBPF_ERRNO__FORMAT;
746 while ((scn = elf_nextscn(elf, scn)) != NULL) {
752 if (gelf_getshdr(scn, &sh) != &sh) {
753 pr_warning("failed to get section(%d) header from %s\n",
755 err = -LIBBPF_ERRNO__FORMAT;
759 name = elf_strptr(elf, ep->e_shstrndx, sh.sh_name);
761 pr_warning("failed to get section(%d) name from %s\n",
763 err = -LIBBPF_ERRNO__FORMAT;
767 data = elf_getdata(scn, 0);
769 pr_warning("failed to get section(%d) data from %s(%s)\n",
770 idx, name, obj->path);
771 err = -LIBBPF_ERRNO__FORMAT;
774 pr_debug("section(%d) %s, size %ld, link %d, flags %lx, type=%d\n",
775 idx, name, (unsigned long)data->d_size,
776 (int)sh.sh_link, (unsigned long)sh.sh_flags,
779 if (strcmp(name, "license") == 0)
780 err = bpf_object__init_license(obj,
783 else if (strcmp(name, "version") == 0)
784 err = bpf_object__init_kversion(obj,
787 else if (strcmp(name, "maps") == 0)
788 obj->efile.maps_shndx = idx;
789 else if (strcmp(name, BTF_ELF_SEC) == 0) {
790 obj->btf = btf__new(data->d_buf, data->d_size,
792 if (IS_ERR(obj->btf)) {
793 pr_warning("Error loading ELF section %s: %ld. Ignored and continue.\n",
794 BTF_ELF_SEC, PTR_ERR(obj->btf));
797 } else if (sh.sh_type == SHT_SYMTAB) {
798 if (obj->efile.symbols) {
799 pr_warning("bpf: multiple SYMTAB in %s\n",
801 err = -LIBBPF_ERRNO__FORMAT;
803 obj->efile.symbols = data;
804 obj->efile.strtabidx = sh.sh_link;
806 } else if ((sh.sh_type == SHT_PROGBITS) &&
807 (sh.sh_flags & SHF_EXECINSTR) &&
808 (data->d_size > 0)) {
809 if (strcmp(name, ".text") == 0)
810 obj->efile.text_shndx = idx;
811 err = bpf_object__add_program(obj, data->d_buf,
812 data->d_size, name, idx);
814 char errmsg[STRERR_BUFSIZE];
815 char *cp = libbpf_strerror_r(-err, errmsg,
818 pr_warning("failed to alloc program %s (%s): %s",
819 name, obj->path, cp);
821 } else if (sh.sh_type == SHT_REL) {
822 void *reloc = obj->efile.reloc;
823 int nr_reloc = obj->efile.nr_reloc + 1;
824 int sec = sh.sh_info; /* points to other section */
826 /* Only do relo for section with exec instructions */
827 if (!section_have_execinstr(obj, sec)) {
828 pr_debug("skip relo %s(%d) for section(%d)\n",
833 reloc = reallocarray(reloc, nr_reloc,
834 sizeof(*obj->efile.reloc));
836 pr_warning("realloc failed\n");
839 int n = nr_reloc - 1;
841 obj->efile.reloc = reloc;
842 obj->efile.nr_reloc = nr_reloc;
844 obj->efile.reloc[n].shdr = sh;
845 obj->efile.reloc[n].data = data;
848 pr_debug("skip section(%d) %s\n", idx, name);
854 if (!obj->efile.strtabidx || obj->efile.strtabidx >= idx) {
855 pr_warning("Corrupted ELF file: index of strtab invalid\n");
856 return LIBBPF_ERRNO__FORMAT;
858 if (obj->efile.maps_shndx >= 0) {
859 err = bpf_object__init_maps(obj);
863 err = bpf_object__init_prog_names(obj);
868 static struct bpf_program *
869 bpf_object__find_prog_by_idx(struct bpf_object *obj, int idx)
871 struct bpf_program *prog;
874 for (i = 0; i < obj->nr_programs; i++) {
875 prog = &obj->programs[i];
876 if (prog->idx == idx)
883 bpf_object__find_program_by_title(struct bpf_object *obj, const char *title)
885 struct bpf_program *pos;
887 bpf_object__for_each_program(pos, obj) {
888 if (pos->section_name && !strcmp(pos->section_name, title))
895 bpf_program__collect_reloc(struct bpf_program *prog, GElf_Shdr *shdr,
896 Elf_Data *data, struct bpf_object *obj)
898 Elf_Data *symbols = obj->efile.symbols;
899 int text_shndx = obj->efile.text_shndx;
900 int maps_shndx = obj->efile.maps_shndx;
901 struct bpf_map *maps = obj->maps;
902 size_t nr_maps = obj->nr_maps;
905 pr_debug("collecting relocating info for: '%s'\n",
907 nrels = shdr->sh_size / shdr->sh_entsize;
909 prog->reloc_desc = malloc(sizeof(*prog->reloc_desc) * nrels);
910 if (!prog->reloc_desc) {
911 pr_warning("failed to alloc memory in relocation\n");
914 prog->nr_reloc = nrels;
916 for (i = 0; i < nrels; i++) {
919 unsigned int insn_idx;
920 struct bpf_insn *insns = prog->insns;
923 if (!gelf_getrel(data, i, &rel)) {
924 pr_warning("relocation: failed to get %d reloc\n", i);
925 return -LIBBPF_ERRNO__FORMAT;
928 if (!gelf_getsym(symbols,
929 GELF_R_SYM(rel.r_info),
931 pr_warning("relocation: symbol %"PRIx64" not found\n",
932 GELF_R_SYM(rel.r_info));
933 return -LIBBPF_ERRNO__FORMAT;
935 pr_debug("relo for %lld value %lld name %d\n",
936 (long long) (rel.r_info >> 32),
937 (long long) sym.st_value, sym.st_name);
939 if (sym.st_shndx != maps_shndx && sym.st_shndx != text_shndx) {
940 pr_warning("Program '%s' contains non-map related relo data pointing to section %u\n",
941 prog->section_name, sym.st_shndx);
942 return -LIBBPF_ERRNO__RELOC;
945 insn_idx = rel.r_offset / sizeof(struct bpf_insn);
946 pr_debug("relocation: insn_idx=%u\n", insn_idx);
948 if (insns[insn_idx].code == (BPF_JMP | BPF_CALL)) {
949 if (insns[insn_idx].src_reg != BPF_PSEUDO_CALL) {
950 pr_warning("incorrect bpf_call opcode\n");
951 return -LIBBPF_ERRNO__RELOC;
953 prog->reloc_desc[i].type = RELO_CALL;
954 prog->reloc_desc[i].insn_idx = insn_idx;
955 prog->reloc_desc[i].text_off = sym.st_value;
956 obj->has_pseudo_calls = true;
960 if (insns[insn_idx].code != (BPF_LD | BPF_IMM | BPF_DW)) {
961 pr_warning("bpf: relocation: invalid relo for insns[%d].code 0x%x\n",
962 insn_idx, insns[insn_idx].code);
963 return -LIBBPF_ERRNO__RELOC;
966 /* TODO: 'maps' is sorted. We can use bsearch to make it faster. */
967 for (map_idx = 0; map_idx < nr_maps; map_idx++) {
968 if (maps[map_idx].offset == sym.st_value) {
969 pr_debug("relocation: find map %zd (%s) for insn %u\n",
970 map_idx, maps[map_idx].name, insn_idx);
975 if (map_idx >= nr_maps) {
976 pr_warning("bpf relocation: map_idx %d large than %d\n",
977 (int)map_idx, (int)nr_maps - 1);
978 return -LIBBPF_ERRNO__RELOC;
981 prog->reloc_desc[i].type = RELO_LD64;
982 prog->reloc_desc[i].insn_idx = insn_idx;
983 prog->reloc_desc[i].map_idx = map_idx;
988 static int bpf_map_find_btf_info(struct bpf_map *map, const struct btf *btf)
990 const struct btf_type *container_type;
991 const struct btf_member *key, *value;
992 struct bpf_map_def *def = &map->def;
993 const size_t max_name = 256;
994 char container_name[max_name];
995 __s64 key_size, value_size;
998 if (snprintf(container_name, max_name, "____btf_map_%s", map->name) ==
1000 pr_warning("map:%s length of '____btf_map_%s' is too long\n",
1001 map->name, map->name);
1005 container_id = btf__find_by_name(btf, container_name);
1006 if (container_id < 0) {
1007 pr_debug("map:%s container_name:%s cannot be found in BTF. Missing BPF_ANNOTATE_KV_PAIR?\n",
1008 map->name, container_name);
1009 return container_id;
1012 container_type = btf__type_by_id(btf, container_id);
1013 if (!container_type) {
1014 pr_warning("map:%s cannot find BTF type for container_id:%u\n",
1015 map->name, container_id);
1019 if (BTF_INFO_KIND(container_type->info) != BTF_KIND_STRUCT ||
1020 BTF_INFO_VLEN(container_type->info) < 2) {
1021 pr_warning("map:%s container_name:%s is an invalid container struct\n",
1022 map->name, container_name);
1026 key = (struct btf_member *)(container_type + 1);
1029 key_size = btf__resolve_size(btf, key->type);
1031 pr_warning("map:%s invalid BTF key_type_size\n",
1036 if (def->key_size != key_size) {
1037 pr_warning("map:%s btf_key_type_size:%u != map_def_key_size:%u\n",
1038 map->name, (__u32)key_size, def->key_size);
1042 value_size = btf__resolve_size(btf, value->type);
1043 if (value_size < 0) {
1044 pr_warning("map:%s invalid BTF value_type_size\n", map->name);
1048 if (def->value_size != value_size) {
1049 pr_warning("map:%s btf_value_type_size:%u != map_def_value_size:%u\n",
1050 map->name, (__u32)value_size, def->value_size);
1054 map->btf_key_type_id = key->type;
1055 map->btf_value_type_id = value->type;
1060 int bpf_map__reuse_fd(struct bpf_map *map, int fd)
1062 struct bpf_map_info info = {};
1063 __u32 len = sizeof(info);
1067 err = bpf_obj_get_info_by_fd(fd, &info, &len);
1071 new_name = strdup(info.name);
1075 new_fd = open("/", O_RDONLY | O_CLOEXEC);
1077 goto err_free_new_name;
1079 new_fd = dup3(fd, new_fd, O_CLOEXEC);
1081 goto err_close_new_fd;
1083 err = zclose(map->fd);
1085 goto err_close_new_fd;
1089 map->name = new_name;
1090 map->def.type = info.type;
1091 map->def.key_size = info.key_size;
1092 map->def.value_size = info.value_size;
1093 map->def.max_entries = info.max_entries;
1094 map->def.map_flags = info.map_flags;
1095 map->btf_key_type_id = info.btf_key_type_id;
1096 map->btf_value_type_id = info.btf_value_type_id;
1108 bpf_object__create_maps(struct bpf_object *obj)
1110 struct bpf_create_map_attr create_attr = {};
1114 for (i = 0; i < obj->nr_maps; i++) {
1115 struct bpf_map *map = &obj->maps[i];
1116 struct bpf_map_def *def = &map->def;
1117 char *cp, errmsg[STRERR_BUFSIZE];
1118 int *pfd = &map->fd;
1121 pr_debug("skip map create (preset) %s: fd=%d\n",
1122 map->name, map->fd);
1126 create_attr.name = map->name;
1127 create_attr.map_ifindex = map->map_ifindex;
1128 create_attr.map_type = def->type;
1129 create_attr.map_flags = def->map_flags;
1130 create_attr.key_size = def->key_size;
1131 create_attr.value_size = def->value_size;
1132 create_attr.max_entries = def->max_entries;
1133 create_attr.btf_fd = 0;
1134 create_attr.btf_key_type_id = 0;
1135 create_attr.btf_value_type_id = 0;
1137 if (obj->btf && !bpf_map_find_btf_info(map, obj->btf)) {
1138 create_attr.btf_fd = btf__fd(obj->btf);
1139 create_attr.btf_key_type_id = map->btf_key_type_id;
1140 create_attr.btf_value_type_id = map->btf_value_type_id;
1143 *pfd = bpf_create_map_xattr(&create_attr);
1144 if (*pfd < 0 && create_attr.btf_key_type_id) {
1145 cp = libbpf_strerror_r(errno, errmsg, sizeof(errmsg));
1146 pr_warning("Error in bpf_create_map_xattr(%s):%s(%d). Retrying without BTF.\n",
1147 map->name, cp, errno);
1148 create_attr.btf_fd = 0;
1149 create_attr.btf_key_type_id = 0;
1150 create_attr.btf_value_type_id = 0;
1151 map->btf_key_type_id = 0;
1152 map->btf_value_type_id = 0;
1153 *pfd = bpf_create_map_xattr(&create_attr);
1160 cp = libbpf_strerror_r(errno, errmsg, sizeof(errmsg));
1161 pr_warning("failed to create map (name: '%s'): %s\n",
1163 for (j = 0; j < i; j++)
1164 zclose(obj->maps[j].fd);
1167 pr_debug("create map %s: fd=%d\n", map->name, *pfd);
1174 bpf_program__reloc_text(struct bpf_program *prog, struct bpf_object *obj,
1175 struct reloc_desc *relo)
1177 struct bpf_insn *insn, *new_insn;
1178 struct bpf_program *text;
1181 if (relo->type != RELO_CALL)
1182 return -LIBBPF_ERRNO__RELOC;
1184 if (prog->idx == obj->efile.text_shndx) {
1185 pr_warning("relo in .text insn %d into off %d\n",
1186 relo->insn_idx, relo->text_off);
1187 return -LIBBPF_ERRNO__RELOC;
1190 if (prog->main_prog_cnt == 0) {
1191 text = bpf_object__find_prog_by_idx(obj, obj->efile.text_shndx);
1193 pr_warning("no .text section found yet relo into text exist\n");
1194 return -LIBBPF_ERRNO__RELOC;
1196 new_cnt = prog->insns_cnt + text->insns_cnt;
1197 new_insn = reallocarray(prog->insns, new_cnt, sizeof(*insn));
1199 pr_warning("oom in prog realloc\n");
1202 memcpy(new_insn + prog->insns_cnt, text->insns,
1203 text->insns_cnt * sizeof(*insn));
1204 prog->insns = new_insn;
1205 prog->main_prog_cnt = prog->insns_cnt;
1206 prog->insns_cnt = new_cnt;
1207 pr_debug("added %zd insn from %s to prog %s\n",
1208 text->insns_cnt, text->section_name,
1209 prog->section_name);
1211 insn = &prog->insns[relo->insn_idx];
1212 insn->imm += prog->main_prog_cnt - relo->insn_idx;
1217 bpf_program__relocate(struct bpf_program *prog, struct bpf_object *obj)
1221 if (!prog || !prog->reloc_desc)
1224 for (i = 0; i < prog->nr_reloc; i++) {
1225 if (prog->reloc_desc[i].type == RELO_LD64) {
1226 struct bpf_insn *insns = prog->insns;
1227 int insn_idx, map_idx;
1229 insn_idx = prog->reloc_desc[i].insn_idx;
1230 map_idx = prog->reloc_desc[i].map_idx;
1232 if (insn_idx >= (int)prog->insns_cnt) {
1233 pr_warning("relocation out of range: '%s'\n",
1234 prog->section_name);
1235 return -LIBBPF_ERRNO__RELOC;
1237 insns[insn_idx].src_reg = BPF_PSEUDO_MAP_FD;
1238 insns[insn_idx].imm = obj->maps[map_idx].fd;
1240 err = bpf_program__reloc_text(prog, obj,
1241 &prog->reloc_desc[i]);
1247 zfree(&prog->reloc_desc);
1254 bpf_object__relocate(struct bpf_object *obj)
1256 struct bpf_program *prog;
1260 for (i = 0; i < obj->nr_programs; i++) {
1261 prog = &obj->programs[i];
1263 err = bpf_program__relocate(prog, obj);
1265 pr_warning("failed to relocate '%s'\n",
1266 prog->section_name);
1273 static int bpf_object__collect_reloc(struct bpf_object *obj)
1277 if (!obj_elf_valid(obj)) {
1278 pr_warning("Internal error: elf object is closed\n");
1279 return -LIBBPF_ERRNO__INTERNAL;
1282 for (i = 0; i < obj->efile.nr_reloc; i++) {
1283 GElf_Shdr *shdr = &obj->efile.reloc[i].shdr;
1284 Elf_Data *data = obj->efile.reloc[i].data;
1285 int idx = shdr->sh_info;
1286 struct bpf_program *prog;
1288 if (shdr->sh_type != SHT_REL) {
1289 pr_warning("internal error at %d\n", __LINE__);
1290 return -LIBBPF_ERRNO__INTERNAL;
1293 prog = bpf_object__find_prog_by_idx(obj, idx);
1295 pr_warning("relocation failed: no section(%d)\n", idx);
1296 return -LIBBPF_ERRNO__RELOC;
1299 err = bpf_program__collect_reloc(prog,
1309 load_program(enum bpf_prog_type type, enum bpf_attach_type expected_attach_type,
1310 const char *name, struct bpf_insn *insns, int insns_cnt,
1311 char *license, u32 kern_version, int *pfd, int prog_ifindex)
1313 struct bpf_load_program_attr load_attr;
1314 char *cp, errmsg[STRERR_BUFSIZE];
1318 memset(&load_attr, 0, sizeof(struct bpf_load_program_attr));
1319 load_attr.prog_type = type;
1320 load_attr.expected_attach_type = expected_attach_type;
1321 load_attr.name = name;
1322 load_attr.insns = insns;
1323 load_attr.insns_cnt = insns_cnt;
1324 load_attr.license = license;
1325 load_attr.kern_version = kern_version;
1326 load_attr.prog_ifindex = prog_ifindex;
1328 if (!load_attr.insns || !load_attr.insns_cnt)
1331 log_buf = malloc(BPF_LOG_BUF_SIZE);
1333 pr_warning("Alloc log buffer for bpf loader error, continue without log\n");
1335 ret = bpf_load_program_xattr(&load_attr, log_buf, BPF_LOG_BUF_SIZE);
1343 ret = -LIBBPF_ERRNO__LOAD;
1344 cp = libbpf_strerror_r(errno, errmsg, sizeof(errmsg));
1345 pr_warning("load bpf program failed: %s\n", cp);
1347 if (log_buf && log_buf[0] != '\0') {
1348 ret = -LIBBPF_ERRNO__VERIFY;
1349 pr_warning("-- BEGIN DUMP LOG ---\n");
1350 pr_warning("\n%s\n", log_buf);
1351 pr_warning("-- END LOG --\n");
1352 } else if (load_attr.insns_cnt >= BPF_MAXINSNS) {
1353 pr_warning("Program too large (%zu insns), at most %d insns\n",
1354 load_attr.insns_cnt, BPF_MAXINSNS);
1355 ret = -LIBBPF_ERRNO__PROG2BIG;
1357 /* Wrong program type? */
1358 if (load_attr.prog_type != BPF_PROG_TYPE_KPROBE) {
1361 load_attr.prog_type = BPF_PROG_TYPE_KPROBE;
1362 load_attr.expected_attach_type = 0;
1363 fd = bpf_load_program_xattr(&load_attr, NULL, 0);
1366 ret = -LIBBPF_ERRNO__PROGTYPE;
1372 ret = -LIBBPF_ERRNO__KVER;
1381 bpf_program__load(struct bpf_program *prog,
1382 char *license, u32 kern_version)
1386 if (prog->instances.nr < 0 || !prog->instances.fds) {
1387 if (prog->preprocessor) {
1388 pr_warning("Internal error: can't load program '%s'\n",
1389 prog->section_name);
1390 return -LIBBPF_ERRNO__INTERNAL;
1393 prog->instances.fds = malloc(sizeof(int));
1394 if (!prog->instances.fds) {
1395 pr_warning("Not enough memory for BPF fds\n");
1398 prog->instances.nr = 1;
1399 prog->instances.fds[0] = -1;
1402 if (!prog->preprocessor) {
1403 if (prog->instances.nr != 1) {
1404 pr_warning("Program '%s' is inconsistent: nr(%d) != 1\n",
1405 prog->section_name, prog->instances.nr);
1407 err = load_program(prog->type, prog->expected_attach_type,
1408 prog->name, prog->insns, prog->insns_cnt,
1409 license, kern_version, &fd,
1410 prog->prog_ifindex);
1412 prog->instances.fds[0] = fd;
1416 for (i = 0; i < prog->instances.nr; i++) {
1417 struct bpf_prog_prep_result result;
1418 bpf_program_prep_t preprocessor = prog->preprocessor;
1420 bzero(&result, sizeof(result));
1421 err = preprocessor(prog, i, prog->insns,
1422 prog->insns_cnt, &result);
1424 pr_warning("Preprocessing the %dth instance of program '%s' failed\n",
1425 i, prog->section_name);
1429 if (!result.new_insn_ptr || !result.new_insn_cnt) {
1430 pr_debug("Skip loading the %dth instance of program '%s'\n",
1431 i, prog->section_name);
1432 prog->instances.fds[i] = -1;
1438 err = load_program(prog->type, prog->expected_attach_type,
1439 prog->name, result.new_insn_ptr,
1440 result.new_insn_cnt,
1441 license, kern_version, &fd,
1442 prog->prog_ifindex);
1445 pr_warning("Loading the %dth instance of program '%s' failed\n",
1446 i, prog->section_name);
1452 prog->instances.fds[i] = fd;
1456 pr_warning("failed to load program '%s'\n",
1457 prog->section_name);
1458 zfree(&prog->insns);
1459 prog->insns_cnt = 0;
1463 static bool bpf_program__is_function_storage(struct bpf_program *prog,
1464 struct bpf_object *obj)
1466 return prog->idx == obj->efile.text_shndx && obj->has_pseudo_calls;
1470 bpf_object__load_progs(struct bpf_object *obj)
1475 for (i = 0; i < obj->nr_programs; i++) {
1476 if (bpf_program__is_function_storage(&obj->programs[i], obj))
1478 err = bpf_program__load(&obj->programs[i],
1487 static bool bpf_prog_type__needs_kver(enum bpf_prog_type type)
1490 case BPF_PROG_TYPE_SOCKET_FILTER:
1491 case BPF_PROG_TYPE_SCHED_CLS:
1492 case BPF_PROG_TYPE_SCHED_ACT:
1493 case BPF_PROG_TYPE_XDP:
1494 case BPF_PROG_TYPE_CGROUP_SKB:
1495 case BPF_PROG_TYPE_CGROUP_SOCK:
1496 case BPF_PROG_TYPE_LWT_IN:
1497 case BPF_PROG_TYPE_LWT_OUT:
1498 case BPF_PROG_TYPE_LWT_XMIT:
1499 case BPF_PROG_TYPE_LWT_SEG6LOCAL:
1500 case BPF_PROG_TYPE_SOCK_OPS:
1501 case BPF_PROG_TYPE_SK_SKB:
1502 case BPF_PROG_TYPE_CGROUP_DEVICE:
1503 case BPF_PROG_TYPE_SK_MSG:
1504 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
1505 case BPF_PROG_TYPE_LIRC_MODE2:
1506 case BPF_PROG_TYPE_SK_REUSEPORT:
1507 case BPF_PROG_TYPE_FLOW_DISSECTOR:
1509 case BPF_PROG_TYPE_UNSPEC:
1510 case BPF_PROG_TYPE_KPROBE:
1511 case BPF_PROG_TYPE_TRACEPOINT:
1512 case BPF_PROG_TYPE_PERF_EVENT:
1513 case BPF_PROG_TYPE_RAW_TRACEPOINT:
1519 static int bpf_object__validate(struct bpf_object *obj, bool needs_kver)
1521 if (needs_kver && obj->kern_version == 0) {
1522 pr_warning("%s doesn't provide kernel version\n",
1524 return -LIBBPF_ERRNO__KVERSION;
1529 static struct bpf_object *
1530 __bpf_object__open(const char *path, void *obj_buf, size_t obj_buf_sz,
1533 struct bpf_object *obj;
1536 if (elf_version(EV_CURRENT) == EV_NONE) {
1537 pr_warning("failed to init libelf for %s\n", path);
1538 return ERR_PTR(-LIBBPF_ERRNO__LIBELF);
1541 obj = bpf_object__new(path, obj_buf, obj_buf_sz);
1545 CHECK_ERR(bpf_object__elf_init(obj), err, out);
1546 CHECK_ERR(bpf_object__check_endianness(obj), err, out);
1547 CHECK_ERR(bpf_object__elf_collect(obj), err, out);
1548 CHECK_ERR(bpf_object__collect_reloc(obj), err, out);
1549 CHECK_ERR(bpf_object__validate(obj, needs_kver), err, out);
1551 bpf_object__elf_finish(obj);
1554 bpf_object__close(obj);
1555 return ERR_PTR(err);
1558 struct bpf_object *bpf_object__open_xattr(struct bpf_object_open_attr *attr)
1560 /* param validation */
1564 pr_debug("loading %s\n", attr->file);
1566 return __bpf_object__open(attr->file, NULL, 0,
1567 bpf_prog_type__needs_kver(attr->prog_type));
1570 struct bpf_object *bpf_object__open(const char *path)
1572 struct bpf_object_open_attr attr = {
1574 .prog_type = BPF_PROG_TYPE_UNSPEC,
1577 return bpf_object__open_xattr(&attr);
1580 struct bpf_object *bpf_object__open_buffer(void *obj_buf,
1586 /* param validation */
1587 if (!obj_buf || obj_buf_sz <= 0)
1591 snprintf(tmp_name, sizeof(tmp_name), "%lx-%lx",
1592 (unsigned long)obj_buf,
1593 (unsigned long)obj_buf_sz);
1594 tmp_name[sizeof(tmp_name) - 1] = '\0';
1597 pr_debug("loading object '%s' from buffer\n",
1600 return __bpf_object__open(name, obj_buf, obj_buf_sz, true);
1603 int bpf_object__unload(struct bpf_object *obj)
1610 for (i = 0; i < obj->nr_maps; i++)
1611 zclose(obj->maps[i].fd);
1613 for (i = 0; i < obj->nr_programs; i++)
1614 bpf_program__unload(&obj->programs[i]);
1619 int bpf_object__load(struct bpf_object *obj)
1627 pr_warning("object should not be loaded twice\n");
1633 CHECK_ERR(bpf_object__create_maps(obj), err, out);
1634 CHECK_ERR(bpf_object__relocate(obj), err, out);
1635 CHECK_ERR(bpf_object__load_progs(obj), err, out);
1639 bpf_object__unload(obj);
1640 pr_warning("failed to load object '%s'\n", obj->path);
1644 static int check_path(const char *path)
1646 char *cp, errmsg[STRERR_BUFSIZE];
1647 struct statfs st_fs;
1654 dname = strdup(path);
1658 dir = dirname(dname);
1659 if (statfs(dir, &st_fs)) {
1660 cp = libbpf_strerror_r(errno, errmsg, sizeof(errmsg));
1661 pr_warning("failed to statfs %s: %s\n", dir, cp);
1666 if (!err && st_fs.f_type != BPF_FS_MAGIC) {
1667 pr_warning("specified path %s is not on BPF FS\n", path);
1674 int bpf_program__pin_instance(struct bpf_program *prog, const char *path,
1677 char *cp, errmsg[STRERR_BUFSIZE];
1680 err = check_path(path);
1685 pr_warning("invalid program pointer\n");
1689 if (instance < 0 || instance >= prog->instances.nr) {
1690 pr_warning("invalid prog instance %d of prog %s (max %d)\n",
1691 instance, prog->section_name, prog->instances.nr);
1695 if (bpf_obj_pin(prog->instances.fds[instance], path)) {
1696 cp = libbpf_strerror_r(errno, errmsg, sizeof(errmsg));
1697 pr_warning("failed to pin program: %s\n", cp);
1700 pr_debug("pinned program '%s'\n", path);
1705 static int make_dir(const char *path)
1707 char *cp, errmsg[STRERR_BUFSIZE];
1710 if (mkdir(path, 0700) && errno != EEXIST)
1714 cp = libbpf_strerror_r(-err, errmsg, sizeof(errmsg));
1715 pr_warning("failed to mkdir %s: %s\n", path, cp);
1720 int bpf_program__pin(struct bpf_program *prog, const char *path)
1724 err = check_path(path);
1729 pr_warning("invalid program pointer\n");
1733 if (prog->instances.nr <= 0) {
1734 pr_warning("no instances of prog %s to pin\n",
1735 prog->section_name);
1739 err = make_dir(path);
1743 for (i = 0; i < prog->instances.nr; i++) {
1747 len = snprintf(buf, PATH_MAX, "%s/%d", path, i);
1750 else if (len >= PATH_MAX)
1751 return -ENAMETOOLONG;
1753 err = bpf_program__pin_instance(prog, buf, i);
1761 int bpf_map__pin(struct bpf_map *map, const char *path)
1763 char *cp, errmsg[STRERR_BUFSIZE];
1766 err = check_path(path);
1771 pr_warning("invalid map pointer\n");
1775 if (bpf_obj_pin(map->fd, path)) {
1776 cp = libbpf_strerror_r(errno, errmsg, sizeof(errmsg));
1777 pr_warning("failed to pin map: %s\n", cp);
1781 pr_debug("pinned map '%s'\n", path);
1785 int bpf_object__pin(struct bpf_object *obj, const char *path)
1787 struct bpf_program *prog;
1788 struct bpf_map *map;
1795 pr_warning("object not yet loaded; load it first\n");
1799 err = make_dir(path);
1803 bpf_map__for_each(map, obj) {
1807 len = snprintf(buf, PATH_MAX, "%s/%s", path,
1808 bpf_map__name(map));
1811 else if (len >= PATH_MAX)
1812 return -ENAMETOOLONG;
1814 err = bpf_map__pin(map, buf);
1819 bpf_object__for_each_program(prog, obj) {
1823 len = snprintf(buf, PATH_MAX, "%s/%s", path,
1824 prog->section_name);
1827 else if (len >= PATH_MAX)
1828 return -ENAMETOOLONG;
1830 err = bpf_program__pin(prog, buf);
1838 void bpf_object__close(struct bpf_object *obj)
1845 if (obj->clear_priv)
1846 obj->clear_priv(obj, obj->priv);
1848 bpf_object__elf_finish(obj);
1849 bpf_object__unload(obj);
1850 btf__free(obj->btf);
1852 for (i = 0; i < obj->nr_maps; i++) {
1853 zfree(&obj->maps[i].name);
1854 if (obj->maps[i].clear_priv)
1855 obj->maps[i].clear_priv(&obj->maps[i],
1857 obj->maps[i].priv = NULL;
1858 obj->maps[i].clear_priv = NULL;
1863 if (obj->programs && obj->nr_programs) {
1864 for (i = 0; i < obj->nr_programs; i++)
1865 bpf_program__exit(&obj->programs[i]);
1867 zfree(&obj->programs);
1869 list_del(&obj->list);
1874 bpf_object__next(struct bpf_object *prev)
1876 struct bpf_object *next;
1879 next = list_first_entry(&bpf_objects_list,
1883 next = list_next_entry(prev, list);
1885 /* Empty list is noticed here so don't need checking on entry. */
1886 if (&next->list == &bpf_objects_list)
1892 const char *bpf_object__name(struct bpf_object *obj)
1894 return obj ? obj->path : ERR_PTR(-EINVAL);
1897 unsigned int bpf_object__kversion(struct bpf_object *obj)
1899 return obj ? obj->kern_version : 0;
1902 int bpf_object__btf_fd(const struct bpf_object *obj)
1904 return obj->btf ? btf__fd(obj->btf) : -1;
1907 int bpf_object__set_priv(struct bpf_object *obj, void *priv,
1908 bpf_object_clear_priv_t clear_priv)
1910 if (obj->priv && obj->clear_priv)
1911 obj->clear_priv(obj, obj->priv);
1914 obj->clear_priv = clear_priv;
1918 void *bpf_object__priv(struct bpf_object *obj)
1920 return obj ? obj->priv : ERR_PTR(-EINVAL);
1923 static struct bpf_program *
1924 __bpf_program__next(struct bpf_program *prev, struct bpf_object *obj)
1932 return &obj->programs[0];
1934 if (prev->obj != obj) {
1935 pr_warning("error: program handler doesn't match object\n");
1939 idx = (prev - obj->programs) + 1;
1940 if (idx >= obj->nr_programs)
1942 return &obj->programs[idx];
1945 struct bpf_program *
1946 bpf_program__next(struct bpf_program *prev, struct bpf_object *obj)
1948 struct bpf_program *prog = prev;
1951 prog = __bpf_program__next(prog, obj);
1952 } while (prog && bpf_program__is_function_storage(prog, obj));
1957 int bpf_program__set_priv(struct bpf_program *prog, void *priv,
1958 bpf_program_clear_priv_t clear_priv)
1960 if (prog->priv && prog->clear_priv)
1961 prog->clear_priv(prog, prog->priv);
1964 prog->clear_priv = clear_priv;
1968 void *bpf_program__priv(struct bpf_program *prog)
1970 return prog ? prog->priv : ERR_PTR(-EINVAL);
1973 void bpf_program__set_ifindex(struct bpf_program *prog, __u32 ifindex)
1975 prog->prog_ifindex = ifindex;
1978 const char *bpf_program__title(struct bpf_program *prog, bool needs_copy)
1982 title = prog->section_name;
1984 title = strdup(title);
1986 pr_warning("failed to strdup program title\n");
1987 return ERR_PTR(-ENOMEM);
1994 int bpf_program__fd(struct bpf_program *prog)
1996 return bpf_program__nth_fd(prog, 0);
1999 int bpf_program__set_prep(struct bpf_program *prog, int nr_instances,
2000 bpf_program_prep_t prep)
2004 if (nr_instances <= 0 || !prep)
2007 if (prog->instances.nr > 0 || prog->instances.fds) {
2008 pr_warning("Can't set pre-processor after loading\n");
2012 instances_fds = malloc(sizeof(int) * nr_instances);
2013 if (!instances_fds) {
2014 pr_warning("alloc memory failed for fds\n");
2018 /* fill all fd with -1 */
2019 memset(instances_fds, -1, sizeof(int) * nr_instances);
2021 prog->instances.nr = nr_instances;
2022 prog->instances.fds = instances_fds;
2023 prog->preprocessor = prep;
2027 int bpf_program__nth_fd(struct bpf_program *prog, int n)
2034 if (n >= prog->instances.nr || n < 0) {
2035 pr_warning("Can't get the %dth fd from program %s: only %d instances\n",
2036 n, prog->section_name, prog->instances.nr);
2040 fd = prog->instances.fds[n];
2042 pr_warning("%dth instance of program '%s' is invalid\n",
2043 n, prog->section_name);
2050 void bpf_program__set_type(struct bpf_program *prog, enum bpf_prog_type type)
2055 static bool bpf_program__is_type(struct bpf_program *prog,
2056 enum bpf_prog_type type)
2058 return prog ? (prog->type == type) : false;
2061 #define BPF_PROG_TYPE_FNS(NAME, TYPE) \
2062 int bpf_program__set_##NAME(struct bpf_program *prog) \
2066 bpf_program__set_type(prog, TYPE); \
2070 bool bpf_program__is_##NAME(struct bpf_program *prog) \
2072 return bpf_program__is_type(prog, TYPE); \
2075 BPF_PROG_TYPE_FNS(socket_filter, BPF_PROG_TYPE_SOCKET_FILTER);
2076 BPF_PROG_TYPE_FNS(kprobe, BPF_PROG_TYPE_KPROBE);
2077 BPF_PROG_TYPE_FNS(sched_cls, BPF_PROG_TYPE_SCHED_CLS);
2078 BPF_PROG_TYPE_FNS(sched_act, BPF_PROG_TYPE_SCHED_ACT);
2079 BPF_PROG_TYPE_FNS(tracepoint, BPF_PROG_TYPE_TRACEPOINT);
2080 BPF_PROG_TYPE_FNS(raw_tracepoint, BPF_PROG_TYPE_RAW_TRACEPOINT);
2081 BPF_PROG_TYPE_FNS(xdp, BPF_PROG_TYPE_XDP);
2082 BPF_PROG_TYPE_FNS(perf_event, BPF_PROG_TYPE_PERF_EVENT);
2084 void bpf_program__set_expected_attach_type(struct bpf_program *prog,
2085 enum bpf_attach_type type)
2087 prog->expected_attach_type = type;
2090 #define BPF_PROG_SEC_IMPL(string, ptype, eatype, atype) \
2091 { string, sizeof(string) - 1, ptype, eatype, atype }
2093 /* Programs that can NOT be attached. */
2094 #define BPF_PROG_SEC(string, ptype) BPF_PROG_SEC_IMPL(string, ptype, 0, -EINVAL)
2096 /* Programs that can be attached. */
2097 #define BPF_APROG_SEC(string, ptype, atype) \
2098 BPF_PROG_SEC_IMPL(string, ptype, 0, atype)
2100 /* Programs that must specify expected attach type at load time. */
2101 #define BPF_EAPROG_SEC(string, ptype, eatype) \
2102 BPF_PROG_SEC_IMPL(string, ptype, eatype, eatype)
2104 /* Programs that can be attached but attach type can't be identified by section
2105 * name. Kept for backward compatibility.
2107 #define BPF_APROG_COMPAT(string, ptype) BPF_PROG_SEC(string, ptype)
2109 static const struct {
2112 enum bpf_prog_type prog_type;
2113 enum bpf_attach_type expected_attach_type;
2114 enum bpf_attach_type attach_type;
2115 } section_names[] = {
2116 BPF_PROG_SEC("socket", BPF_PROG_TYPE_SOCKET_FILTER),
2117 BPF_PROG_SEC("kprobe/", BPF_PROG_TYPE_KPROBE),
2118 BPF_PROG_SEC("kretprobe/", BPF_PROG_TYPE_KPROBE),
2119 BPF_PROG_SEC("classifier", BPF_PROG_TYPE_SCHED_CLS),
2120 BPF_PROG_SEC("action", BPF_PROG_TYPE_SCHED_ACT),
2121 BPF_PROG_SEC("tracepoint/", BPF_PROG_TYPE_TRACEPOINT),
2122 BPF_PROG_SEC("raw_tracepoint/", BPF_PROG_TYPE_RAW_TRACEPOINT),
2123 BPF_PROG_SEC("xdp", BPF_PROG_TYPE_XDP),
2124 BPF_PROG_SEC("perf_event", BPF_PROG_TYPE_PERF_EVENT),
2125 BPF_PROG_SEC("lwt_in", BPF_PROG_TYPE_LWT_IN),
2126 BPF_PROG_SEC("lwt_out", BPF_PROG_TYPE_LWT_OUT),
2127 BPF_PROG_SEC("lwt_xmit", BPF_PROG_TYPE_LWT_XMIT),
2128 BPF_PROG_SEC("lwt_seg6local", BPF_PROG_TYPE_LWT_SEG6LOCAL),
2129 BPF_APROG_SEC("cgroup_skb/ingress", BPF_PROG_TYPE_CGROUP_SKB,
2130 BPF_CGROUP_INET_INGRESS),
2131 BPF_APROG_SEC("cgroup_skb/egress", BPF_PROG_TYPE_CGROUP_SKB,
2132 BPF_CGROUP_INET_EGRESS),
2133 BPF_APROG_COMPAT("cgroup/skb", BPF_PROG_TYPE_CGROUP_SKB),
2134 BPF_APROG_SEC("cgroup/sock", BPF_PROG_TYPE_CGROUP_SOCK,
2135 BPF_CGROUP_INET_SOCK_CREATE),
2136 BPF_EAPROG_SEC("cgroup/post_bind4", BPF_PROG_TYPE_CGROUP_SOCK,
2137 BPF_CGROUP_INET4_POST_BIND),
2138 BPF_EAPROG_SEC("cgroup/post_bind6", BPF_PROG_TYPE_CGROUP_SOCK,
2139 BPF_CGROUP_INET6_POST_BIND),
2140 BPF_APROG_SEC("cgroup/dev", BPF_PROG_TYPE_CGROUP_DEVICE,
2142 BPF_APROG_SEC("sockops", BPF_PROG_TYPE_SOCK_OPS,
2143 BPF_CGROUP_SOCK_OPS),
2144 BPF_APROG_SEC("sk_skb/stream_parser", BPF_PROG_TYPE_SK_SKB,
2145 BPF_SK_SKB_STREAM_PARSER),
2146 BPF_APROG_SEC("sk_skb/stream_verdict", BPF_PROG_TYPE_SK_SKB,
2147 BPF_SK_SKB_STREAM_VERDICT),
2148 BPF_APROG_COMPAT("sk_skb", BPF_PROG_TYPE_SK_SKB),
2149 BPF_APROG_SEC("sk_msg", BPF_PROG_TYPE_SK_MSG,
2150 BPF_SK_MSG_VERDICT),
2151 BPF_APROG_SEC("lirc_mode2", BPF_PROG_TYPE_LIRC_MODE2,
2153 BPF_APROG_SEC("flow_dissector", BPF_PROG_TYPE_FLOW_DISSECTOR,
2154 BPF_FLOW_DISSECTOR),
2155 BPF_EAPROG_SEC("cgroup/bind4", BPF_PROG_TYPE_CGROUP_SOCK_ADDR,
2156 BPF_CGROUP_INET4_BIND),
2157 BPF_EAPROG_SEC("cgroup/bind6", BPF_PROG_TYPE_CGROUP_SOCK_ADDR,
2158 BPF_CGROUP_INET6_BIND),
2159 BPF_EAPROG_SEC("cgroup/connect4", BPF_PROG_TYPE_CGROUP_SOCK_ADDR,
2160 BPF_CGROUP_INET4_CONNECT),
2161 BPF_EAPROG_SEC("cgroup/connect6", BPF_PROG_TYPE_CGROUP_SOCK_ADDR,
2162 BPF_CGROUP_INET6_CONNECT),
2163 BPF_EAPROG_SEC("cgroup/sendmsg4", BPF_PROG_TYPE_CGROUP_SOCK_ADDR,
2164 BPF_CGROUP_UDP4_SENDMSG),
2165 BPF_EAPROG_SEC("cgroup/sendmsg6", BPF_PROG_TYPE_CGROUP_SOCK_ADDR,
2166 BPF_CGROUP_UDP6_SENDMSG),
2169 #undef BPF_PROG_SEC_IMPL
2171 #undef BPF_APROG_SEC
2172 #undef BPF_EAPROG_SEC
2173 #undef BPF_APROG_COMPAT
2175 int libbpf_prog_type_by_name(const char *name, enum bpf_prog_type *prog_type,
2176 enum bpf_attach_type *expected_attach_type)
2183 for (i = 0; i < ARRAY_SIZE(section_names); i++) {
2184 if (strncmp(name, section_names[i].sec, section_names[i].len))
2186 *prog_type = section_names[i].prog_type;
2187 *expected_attach_type = section_names[i].expected_attach_type;
2193 int libbpf_attach_type_by_name(const char *name,
2194 enum bpf_attach_type *attach_type)
2201 for (i = 0; i < ARRAY_SIZE(section_names); i++) {
2202 if (strncmp(name, section_names[i].sec, section_names[i].len))
2204 if (section_names[i].attach_type == -EINVAL)
2206 *attach_type = section_names[i].attach_type;
2213 bpf_program__identify_section(struct bpf_program *prog,
2214 enum bpf_prog_type *prog_type,
2215 enum bpf_attach_type *expected_attach_type)
2217 return libbpf_prog_type_by_name(prog->section_name, prog_type,
2218 expected_attach_type);
2221 int bpf_map__fd(struct bpf_map *map)
2223 return map ? map->fd : -EINVAL;
2226 const struct bpf_map_def *bpf_map__def(struct bpf_map *map)
2228 return map ? &map->def : ERR_PTR(-EINVAL);
2231 const char *bpf_map__name(struct bpf_map *map)
2233 return map ? map->name : NULL;
2236 __u32 bpf_map__btf_key_type_id(const struct bpf_map *map)
2238 return map ? map->btf_key_type_id : 0;
2241 __u32 bpf_map__btf_value_type_id(const struct bpf_map *map)
2243 return map ? map->btf_value_type_id : 0;
2246 int bpf_map__set_priv(struct bpf_map *map, void *priv,
2247 bpf_map_clear_priv_t clear_priv)
2253 if (map->clear_priv)
2254 map->clear_priv(map, map->priv);
2258 map->clear_priv = clear_priv;
2262 void *bpf_map__priv(struct bpf_map *map)
2264 return map ? map->priv : ERR_PTR(-EINVAL);
2267 bool bpf_map__is_offload_neutral(struct bpf_map *map)
2269 return map->def.type == BPF_MAP_TYPE_PERF_EVENT_ARRAY;
2272 void bpf_map__set_ifindex(struct bpf_map *map, __u32 ifindex)
2274 map->map_ifindex = ifindex;
2278 bpf_map__next(struct bpf_map *prev, struct bpf_object *obj)
2281 struct bpf_map *s, *e;
2283 if (!obj || !obj->maps)
2287 e = obj->maps + obj->nr_maps;
2292 if ((prev < s) || (prev >= e)) {
2293 pr_warning("error in %s: map handler doesn't belong to object\n",
2298 idx = (prev - obj->maps) + 1;
2299 if (idx >= obj->nr_maps)
2301 return &obj->maps[idx];
2305 bpf_object__find_map_by_name(struct bpf_object *obj, const char *name)
2307 struct bpf_map *pos;
2309 bpf_map__for_each(pos, obj) {
2310 if (pos->name && !strcmp(pos->name, name))
2317 bpf_object__find_map_by_offset(struct bpf_object *obj, size_t offset)
2321 for (i = 0; i < obj->nr_maps; i++) {
2322 if (obj->maps[i].offset == offset)
2323 return &obj->maps[i];
2325 return ERR_PTR(-ENOENT);
2328 long libbpf_get_error(const void *ptr)
2331 return PTR_ERR(ptr);
2335 int bpf_prog_load(const char *file, enum bpf_prog_type type,
2336 struct bpf_object **pobj, int *prog_fd)
2338 struct bpf_prog_load_attr attr;
2340 memset(&attr, 0, sizeof(struct bpf_prog_load_attr));
2342 attr.prog_type = type;
2343 attr.expected_attach_type = 0;
2345 return bpf_prog_load_xattr(&attr, pobj, prog_fd);
2348 int bpf_prog_load_xattr(const struct bpf_prog_load_attr *attr,
2349 struct bpf_object **pobj, int *prog_fd)
2351 struct bpf_object_open_attr open_attr = {
2353 .prog_type = attr->prog_type,
2355 struct bpf_program *prog, *first_prog = NULL;
2356 enum bpf_attach_type expected_attach_type;
2357 enum bpf_prog_type prog_type;
2358 struct bpf_object *obj;
2359 struct bpf_map *map;
2367 obj = bpf_object__open_xattr(&open_attr);
2368 if (IS_ERR_OR_NULL(obj))
2371 bpf_object__for_each_program(prog, obj) {
2373 * If type is not specified, try to guess it based on
2376 prog_type = attr->prog_type;
2377 prog->prog_ifindex = attr->ifindex;
2378 expected_attach_type = attr->expected_attach_type;
2379 if (prog_type == BPF_PROG_TYPE_UNSPEC) {
2380 err = bpf_program__identify_section(prog, &prog_type,
2381 &expected_attach_type);
2383 pr_warning("failed to guess program type based on section name %s\n",
2384 prog->section_name);
2385 bpf_object__close(obj);
2390 bpf_program__set_type(prog, prog_type);
2391 bpf_program__set_expected_attach_type(prog,
2392 expected_attach_type);
2398 bpf_map__for_each(map, obj) {
2399 if (!bpf_map__is_offload_neutral(map))
2400 map->map_ifindex = attr->ifindex;
2404 pr_warning("object file doesn't contain bpf program\n");
2405 bpf_object__close(obj);
2409 err = bpf_object__load(obj);
2411 bpf_object__close(obj);
2416 *prog_fd = bpf_program__fd(first_prog);
2420 enum bpf_perf_event_ret
2421 bpf_perf_event_read_simple(void *mem, unsigned long size,
2422 unsigned long page_size, void **buf, size_t *buf_len,
2423 bpf_perf_event_print_t fn, void *priv)
2425 volatile struct perf_event_mmap_page *header = mem;
2426 __u64 data_tail = header->data_tail;
2427 __u64 data_head = header->data_head;
2428 int ret = LIBBPF_PERF_EVENT_ERROR;
2429 void *base, *begin, *end;
2431 asm volatile("" ::: "memory"); /* in real code it should be smp_rmb() */
2432 if (data_head == data_tail)
2433 return LIBBPF_PERF_EVENT_CONT;
2435 base = ((char *)header) + page_size;
2437 begin = base + data_tail % size;
2438 end = base + data_head % size;
2440 while (begin != end) {
2441 struct perf_event_header *ehdr;
2444 if (begin + ehdr->size > base + size) {
2445 long len = base + size - begin;
2447 if (*buf_len < ehdr->size) {
2449 *buf = malloc(ehdr->size);
2451 ret = LIBBPF_PERF_EVENT_ERROR;
2454 *buf_len = ehdr->size;
2457 memcpy(*buf, begin, len);
2458 memcpy(*buf + len, base, ehdr->size - len);
2459 ehdr = (void *)*buf;
2460 begin = base + ehdr->size - len;
2461 } else if (begin + ehdr->size == base + size) {
2464 begin += ehdr->size;
2467 ret = fn(ehdr, priv);
2468 if (ret != LIBBPF_PERF_EVENT_CONT)
2471 data_tail += ehdr->size;
2474 __sync_synchronize(); /* smp_mb() */
2475 header->data_tail = data_tail;