diff options
Diffstat (limited to 'tools/lib/bpf')
| -rw-r--r-- | tools/lib/bpf/Build | 2 | ||||
| -rw-r--r-- | tools/lib/bpf/Makefile | 6 | ||||
| -rw-r--r-- | tools/lib/bpf/btf.c | 65 | ||||
| -rw-r--r-- | tools/lib/bpf/btf.h | 3 | ||||
| -rw-r--r-- | tools/lib/bpf/libbpf.c | 237 | ||||
| -rw-r--r-- | tools/lib/bpf/libbpf.h | 13 | ||||
| -rw-r--r-- | tools/lib/bpf/libbpf_errno.c | 74 |
7 files changed, 292 insertions, 108 deletions
diff --git a/tools/lib/bpf/Build b/tools/lib/bpf/Build index 6070e655042d..13a861135127 100644 --- a/tools/lib/bpf/Build +++ b/tools/lib/bpf/Build @@ -1 +1 @@ -libbpf-y := libbpf.o bpf.o nlattr.o btf.o +libbpf-y := libbpf.o bpf.o nlattr.o btf.o libbpf_errno.o diff --git a/tools/lib/bpf/Makefile b/tools/lib/bpf/Makefile index 5390e7725e43..7a8e4c98ef1a 100644 --- a/tools/lib/bpf/Makefile +++ b/tools/lib/bpf/Makefile @@ -66,7 +66,7 @@ ifndef VERBOSE endif FEATURE_USER = .libbpf -FEATURE_TESTS = libelf libelf-getphdrnum libelf-mmap bpf +FEATURE_TESTS = libelf libelf-getphdrnum libelf-mmap bpf reallocarray FEATURE_DISPLAY = libelf bpf INCLUDES = -I. -I$(srctree)/tools/include -I$(srctree)/tools/arch/$(ARCH)/include/uapi -I$(srctree)/tools/include/uapi -I$(srctree)/tools/perf @@ -120,6 +120,10 @@ ifeq ($(feature-libelf-getphdrnum), 1) override CFLAGS += -DHAVE_ELF_GETPHDRNUM_SUPPORT endif +ifeq ($(feature-reallocarray), 0) + override CFLAGS += -DCOMPAT_NEED_REALLOCARRAY +endif + # Append required CFLAGS override CFLAGS += $(EXTRA_WARNINGS) override CFLAGS += -Werror -Wall diff --git a/tools/lib/bpf/btf.c b/tools/lib/bpf/btf.c index 8c54a4b6f187..03161be094b4 100644 --- a/tools/lib/bpf/btf.c +++ b/tools/lib/bpf/btf.c @@ -17,6 +17,11 @@ #define BTF_MAX_NR_TYPES 65535 +#define IS_MODIFIER(k) (((k) == BTF_KIND_TYPEDEF) || \ + ((k) == BTF_KIND_VOLATILE) || \ + ((k) == BTF_KIND_CONST) || \ + ((k) == BTF_KIND_RESTRICT)) + static struct btf_type btf_void; struct btf { @@ -33,14 +38,6 @@ struct btf { int fd; }; -static const char *btf_name_by_offset(const struct btf *btf, uint32_t offset) -{ - if (offset < btf->hdr->str_len) - return &btf->strings[offset]; - else - return NULL; -} - static int btf_add_type(struct btf *btf, struct btf_type *t) { if (btf->types_size - btf->nr_types < 2) { @@ -190,15 +187,6 @@ static int btf_parse_type_sec(struct btf *btf, btf_print_fn_t err_log) return 0; } -static const struct btf_type *btf_type_by_id(const struct btf *btf, - uint32_t type_id) -{ - if (type_id > btf->nr_types) - return NULL; - - return btf->types[type_id]; -} - static bool btf_type_is_void(const struct btf_type *t) { return t == &btf_void || BTF_INFO_KIND(t->info) == BTF_KIND_FWD; @@ -234,7 +222,7 @@ int64_t btf__resolve_size(const struct btf *btf, uint32_t type_id) int64_t size = -1; int i; - t = btf_type_by_id(btf, type_id); + t = btf__type_by_id(btf, type_id); for (i = 0; i < MAX_RESOLVE_DEPTH && !btf_type_is_void_or_null(t); i++) { size = btf_type_size(t); @@ -259,7 +247,7 @@ int64_t btf__resolve_size(const struct btf *btf, uint32_t type_id) return -EINVAL; } - t = btf_type_by_id(btf, type_id); + t = btf__type_by_id(btf, type_id); } if (size < 0) @@ -271,6 +259,26 @@ int64_t btf__resolve_size(const struct btf *btf, uint32_t type_id) return nelems * size; } +int btf__resolve_type(const struct btf *btf, __u32 type_id) +{ + const struct btf_type *t; + int depth = 0; + + t = btf__type_by_id(btf, type_id); + while (depth < MAX_RESOLVE_DEPTH && + !btf_type_is_void_or_null(t) && + IS_MODIFIER(BTF_INFO_KIND(t->info))) { + type_id = t->type; + t = btf__type_by_id(btf, type_id); + depth++; + } + + if (depth == MAX_RESOLVE_DEPTH || btf_type_is_void_or_null(t)) + return -EINVAL; + + return type_id; +} + int32_t btf__find_by_name(const struct btf *btf, const char *type_name) { uint32_t i; @@ -280,7 +288,7 @@ int32_t btf__find_by_name(const struct btf *btf, const char *type_name) for (i = 1; i <= btf->nr_types; i++) { const struct btf_type *t = btf->types[i]; - const char *name = btf_name_by_offset(btf, t->name_off); + const char *name = btf__name_by_offset(btf, t->name_off); if (name && !strcmp(type_name, name)) return i; @@ -371,3 +379,20 @@ int btf__fd(const struct btf *btf) { return btf->fd; } + +const char *btf__name_by_offset(const struct btf *btf, __u32 offset) +{ + if (offset < btf->hdr->str_len) + return &btf->strings[offset]; + else + return NULL; +} + +const struct btf_type *btf__type_by_id(const struct btf *btf, + __u32 type_id) +{ + if (type_id > btf->nr_types) + return NULL; + + return btf->types[type_id]; +} diff --git a/tools/lib/bpf/btf.h b/tools/lib/bpf/btf.h index 74bb344035bb..24f361d99a5e 100644 --- a/tools/lib/bpf/btf.h +++ b/tools/lib/bpf/btf.h @@ -17,6 +17,9 @@ void btf__free(struct btf *btf); struct btf *btf__new(uint8_t *data, uint32_t size, btf_print_fn_t err_log); int32_t btf__find_by_name(const struct btf *btf, const char *type_name); int64_t btf__resolve_size(const struct btf *btf, uint32_t type_id); +int btf__resolve_type(const struct btf *btf, __u32 type_id); int btf__fd(const struct btf *btf); +const char *btf__name_by_offset(const struct btf *btf, __u32 offset); +const struct btf_type *btf__type_by_id(const struct btf *btf, __u32 type_id); #endif diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index a1e96b5de5ff..955f8eafbf41 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -22,6 +22,7 @@ * License along with this program; if not, see <http://www.gnu.org/licenses> */ +#define _GNU_SOURCE #include <stdlib.h> #include <stdio.h> #include <stdarg.h> @@ -41,6 +42,7 @@ #include <sys/stat.h> #include <sys/types.h> #include <sys/vfs.h> +#include <tools/libc_compat.h> #include <libelf.h> #include <gelf.h> @@ -95,54 +97,6 @@ void libbpf_set_print(libbpf_print_fn_t warn, #define STRERR_BUFSIZE 128 -#define ERRNO_OFFSET(e) ((e) - __LIBBPF_ERRNO__START) -#define ERRCODE_OFFSET(c) ERRNO_OFFSET(LIBBPF_ERRNO__##c) -#define NR_ERRNO (__LIBBPF_ERRNO__END - __LIBBPF_ERRNO__START) - -static const char *libbpf_strerror_table[NR_ERRNO] = { - [ERRCODE_OFFSET(LIBELF)] = "Something wrong in libelf", - [ERRCODE_OFFSET(FORMAT)] = "BPF object format invalid", - [ERRCODE_OFFSET(KVERSION)] = "'version' section incorrect or lost", - [ERRCODE_OFFSET(ENDIAN)] = "Endian mismatch", - [ERRCODE_OFFSET(INTERNAL)] = "Internal error in libbpf", - [ERRCODE_OFFSET(RELOC)] = "Relocation failed", - [ERRCODE_OFFSET(VERIFY)] = "Kernel verifier blocks program loading", - [ERRCODE_OFFSET(PROG2BIG)] = "Program too big", - [ERRCODE_OFFSET(KVER)] = "Incorrect kernel version", - [ERRCODE_OFFSET(PROGTYPE)] = "Kernel doesn't support this program type", - [ERRCODE_OFFSET(WRNGPID)] = "Wrong pid in netlink message", - [ERRCODE_OFFSET(INVSEQ)] = "Invalid netlink sequence", -}; - -int libbpf_strerror(int err, char *buf, size_t size) -{ - if (!buf || !size) - return -1; - - err = err > 0 ? err : -err; - - if (err < __LIBBPF_ERRNO__START) { - int ret; - - ret = strerror_r(err, buf, size); - buf[size - 1] = '\0'; - return ret; - } - - if (err < __LIBBPF_ERRNO__END) { - const char *msg; - - msg = libbpf_strerror_table[ERRNO_OFFSET(err)]; - snprintf(buf, size, "%s", msg); - buf[size - 1] = '\0'; - return 0; - } - - snprintf(buf, size, "Unknown libbpf error %d", err); - buf[size - 1] = '\0'; - return -1; -} - #define CHECK_ERR(action, err, out) do { \ err = action; \ if (err) \ @@ -234,6 +188,7 @@ struct bpf_object { size_t nr_maps; bool loaded; + bool has_pseudo_calls; /* * Information when doing elf related work. Only valid if fd @@ -368,7 +323,7 @@ bpf_object__add_program(struct bpf_object *obj, void *data, size_t size, progs = obj->programs; nr_progs = obj->nr_programs; - progs = realloc(progs, sizeof(progs[0]) * (nr_progs + 1)); + progs = reallocarray(progs, nr_progs + 1, sizeof(progs[0])); if (!progs) { /* * In this case the original obj->programs @@ -400,10 +355,6 @@ bpf_object__init_prog_names(struct bpf_object *obj) const char *name = NULL; prog = &obj->programs[pi]; - if (prog->idx == obj->efile.text_shndx) { - name = ".text"; - goto skip_search; - } for (si = 0; si < symbols->d_size / sizeof(GElf_Sym) && !name; si++) { @@ -426,12 +377,15 @@ bpf_object__init_prog_names(struct bpf_object *obj) } } + if (!name && prog->idx == obj->efile.text_shndx) + name = ".text"; + if (!name) { pr_warning("failed to find sym for prog %s\n", prog->section_name); return -EINVAL; } -skip_search: + prog->name = strdup(name); if (!prog->name) { pr_warning("failed to allocate memory for prog sym %s\n", @@ -870,8 +824,8 @@ static int bpf_object__elf_collect(struct bpf_object *obj) continue; } - reloc = realloc(reloc, - sizeof(*obj->efile.reloc) * nr_reloc); + reloc = reallocarray(reloc, nr_reloc, + sizeof(*obj->efile.reloc)); if (!reloc) { pr_warning("realloc failed\n"); err = -ENOMEM; @@ -981,6 +935,7 @@ bpf_program__collect_reloc(struct bpf_program *prog, GElf_Shdr *shdr, prog->reloc_desc[i].type = RELO_CALL; prog->reloc_desc[i].insn_idx = insn_idx; prog->reloc_desc[i].text_off = sym.st_value; + obj->has_pseudo_calls = true; continue; } @@ -1080,6 +1035,53 @@ static int bpf_map_find_btf_info(struct bpf_map *map, const struct btf *btf) return 0; } +int bpf_map__reuse_fd(struct bpf_map *map, int fd) +{ + struct bpf_map_info info = {}; + __u32 len = sizeof(info); + int new_fd, err; + char *new_name; + + err = bpf_obj_get_info_by_fd(fd, &info, &len); + if (err) + return err; + + new_name = strdup(info.name); + if (!new_name) + return -errno; + + new_fd = open("/", O_RDONLY | O_CLOEXEC); + if (new_fd < 0) + goto err_free_new_name; + + new_fd = dup3(fd, new_fd, O_CLOEXEC); + if (new_fd < 0) + goto err_close_new_fd; + + err = zclose(map->fd); + if (err) + goto err_close_new_fd; + free(map->name); + + map->fd = new_fd; + map->name = new_name; + map->def.type = info.type; + map->def.key_size = info.key_size; + map->def.value_size = info.value_size; + map->def.max_entries = info.max_entries; + map->def.map_flags = info.map_flags; + map->btf_key_type_id = info.btf_key_type_id; + map->btf_value_type_id = info.btf_value_type_id; + + return 0; + +err_close_new_fd: + close(new_fd); +err_free_new_name: + free(new_name); + return -errno; +} + static int bpf_object__create_maps(struct bpf_object *obj) { @@ -1092,6 +1094,12 @@ bpf_object__create_maps(struct bpf_object *obj) struct bpf_map_def *def = &map->def; int *pfd = &map->fd; + if (map->fd >= 0) { + pr_debug("skip map create (preset) %s: fd=%d\n", + map->name, map->fd); + continue; + } + create_attr.name = map->name; create_attr.map_ifindex = map->map_ifindex; create_attr.map_type = def->type; @@ -1162,7 +1170,7 @@ bpf_program__reloc_text(struct bpf_program *prog, struct bpf_object *obj, return -LIBBPF_ERRNO__RELOC; } new_cnt = prog->insns_cnt + text->insns_cnt; - new_insn = realloc(prog->insns, new_cnt * sizeof(*insn)); + new_insn = reallocarray(prog->insns, new_cnt, sizeof(*insn)); if (!new_insn) { pr_warning("oom in prog realloc\n"); return -ENOMEM; @@ -1426,6 +1434,12 @@ out: return err; } +static bool bpf_program__is_function_storage(struct bpf_program *prog, + struct bpf_object *obj) +{ + return prog->idx == obj->efile.text_shndx && obj->has_pseudo_calls; +} + static int bpf_object__load_progs(struct bpf_object *obj) { @@ -1433,7 +1447,7 @@ bpf_object__load_progs(struct bpf_object *obj) int err; for (i = 0; i < obj->nr_programs; i++) { - if (obj->programs[i].idx == obj->efile.text_shndx) + if (bpf_program__is_function_storage(&obj->programs[i], obj)) continue; err = bpf_program__load(&obj->programs[i], obj->license, @@ -1513,15 +1527,26 @@ out: return ERR_PTR(err); } -struct bpf_object *bpf_object__open(const char *path) +struct bpf_object *bpf_object__open_xattr(struct bpf_object_open_attr *attr) { /* param validation */ - if (!path) + if (!attr->file) return NULL; - pr_debug("loading %s\n", path); + pr_debug("loading %s\n", attr->file); + + return __bpf_object__open(attr->file, NULL, 0, + bpf_prog_type__needs_kver(attr->prog_type)); +} - return __bpf_object__open(path, NULL, 0, true); +struct bpf_object *bpf_object__open(const char *path) +{ + struct bpf_object_open_attr attr = { + .file = path, + .prog_type = BPF_PROG_TYPE_UNSPEC, + }; + + return bpf_object__open_xattr(&attr); } struct bpf_object *bpf_object__open_buffer(void *obj_buf, @@ -1858,8 +1883,8 @@ void *bpf_object__priv(struct bpf_object *obj) return obj ? obj->priv : ERR_PTR(-EINVAL); } -struct bpf_program * -bpf_program__next(struct bpf_program *prev, struct bpf_object *obj) +static struct bpf_program * +__bpf_program__next(struct bpf_program *prev, struct bpf_object *obj) { size_t idx; @@ -1880,6 +1905,18 @@ bpf_program__next(struct bpf_program *prev, struct bpf_object *obj) return &obj->programs[idx]; } +struct bpf_program * +bpf_program__next(struct bpf_program *prev, struct bpf_object *obj) +{ + struct bpf_program *prog = prev; + + do { + prog = __bpf_program__next(prog, obj); + } while (prog && bpf_program__is_function_storage(prog, obj)); + + return prog; +} + int bpf_program__set_priv(struct bpf_program *prog, void *priv, bpf_program_clear_priv_t clear_priv) { @@ -1896,6 +1933,11 @@ void *bpf_program__priv(struct bpf_program *prog) return prog ? prog->priv : ERR_PTR(-EINVAL); } +void bpf_program__set_ifindex(struct bpf_program *prog, __u32 ifindex) +{ + prog->prog_ifindex = ifindex; +} + const char *bpf_program__title(struct bpf_program *prog, bool needs_copy) { const char *title; @@ -2037,9 +2079,11 @@ static const struct { BPF_PROG_SEC("lwt_in", BPF_PROG_TYPE_LWT_IN), BPF_PROG_SEC("lwt_out", BPF_PROG_TYPE_LWT_OUT), BPF_PROG_SEC("lwt_xmit", BPF_PROG_TYPE_LWT_XMIT), + BPF_PROG_SEC("lwt_seg6local", BPF_PROG_TYPE_LWT_SEG6LOCAL), BPF_PROG_SEC("sockops", BPF_PROG_TYPE_SOCK_OPS), BPF_PROG_SEC("sk_skb", BPF_PROG_TYPE_SK_SKB), BPF_PROG_SEC("sk_msg", BPF_PROG_TYPE_SK_MSG), + BPF_PROG_SEC("lirc_mode2", BPF_PROG_TYPE_LIRC_MODE2), BPF_SA_PROG_SEC("cgroup/bind4", BPF_CGROUP_INET4_BIND), BPF_SA_PROG_SEC("cgroup/bind6", BPF_CGROUP_INET6_BIND), BPF_SA_PROG_SEC("cgroup/connect4", BPF_CGROUP_INET4_CONNECT), @@ -2055,23 +2099,31 @@ static const struct { #undef BPF_S_PROG_SEC #undef BPF_SA_PROG_SEC -static int bpf_program__identify_section(struct bpf_program *prog) +int libbpf_prog_type_by_name(const char *name, enum bpf_prog_type *prog_type, + enum bpf_attach_type *expected_attach_type) { int i; - if (!prog->section_name) - goto err; - - for (i = 0; i < ARRAY_SIZE(section_names); i++) - if (strncmp(prog->section_name, section_names[i].sec, - section_names[i].len) == 0) - return i; + if (!name) + return -EINVAL; -err: - pr_warning("failed to guess program type based on section name %s\n", - prog->section_name); + for (i = 0; i < ARRAY_SIZE(section_names); i++) { + if (strncmp(name, section_names[i].sec, section_names[i].len)) + continue; + *prog_type = section_names[i].prog_type; + *expected_attach_type = section_names[i].expected_attach_type; + return 0; + } + return -EINVAL; +} - return -1; +static int +bpf_program__identify_section(struct bpf_program *prog, + enum bpf_prog_type *prog_type, + enum bpf_attach_type *expected_attach_type) +{ + return libbpf_prog_type_by_name(prog->section_name, prog_type, + expected_attach_type); } int bpf_map__fd(struct bpf_map *map) @@ -2120,6 +2172,16 @@ void *bpf_map__priv(struct bpf_map *map) return map ? map->priv : ERR_PTR(-EINVAL); } +bool bpf_map__is_offload_neutral(struct bpf_map *map) +{ + return map->def.type == BPF_MAP_TYPE_PERF_EVENT_ARRAY; +} + +void bpf_map__set_ifindex(struct bpf_map *map, __u32 ifindex) +{ + map->map_ifindex = ifindex; +} + struct bpf_map * bpf_map__next(struct bpf_map *prev, struct bpf_object *obj) { @@ -2194,12 +2256,15 @@ int bpf_prog_load(const char *file, enum bpf_prog_type type, int bpf_prog_load_xattr(const struct bpf_prog_load_attr *attr, struct bpf_object **pobj, int *prog_fd) { + struct bpf_object_open_attr open_attr = { + .file = attr->file, + .prog_type = attr->prog_type, + }; struct bpf_program *prog, *first_prog = NULL; enum bpf_attach_type expected_attach_type; enum bpf_prog_type prog_type; struct bpf_object *obj; struct bpf_map *map; - int section_idx; int err; if (!attr) @@ -2207,8 +2272,7 @@ int bpf_prog_load_xattr(const struct bpf_prog_load_attr *attr, if (!attr->file) return -EINVAL; - obj = __bpf_object__open(attr->file, NULL, 0, - bpf_prog_type__needs_kver(attr->prog_type)); + obj = bpf_object__open_xattr(&open_attr); if (IS_ERR_OR_NULL(obj)) return -ENOENT; @@ -2221,26 +2285,27 @@ int bpf_prog_load_xattr(const struct bpf_prog_load_attr *attr, prog->prog_ifindex = attr->ifindex; expected_attach_type = attr->expected_attach_type; if (prog_type == BPF_PROG_TYPE_UNSPEC) { - section_idx = bpf_program__identify_section(prog); - if (section_idx < 0) { + err = bpf_program__identify_section(prog, &prog_type, + &expected_attach_type); + if (err < 0) { + pr_warning("failed to guess program type based on section name %s\n", + prog->section_name); bpf_object__close(obj); return -EINVAL; } - prog_type = section_names[section_idx].prog_type; - expected_attach_type = - section_names[section_idx].expected_attach_type; } bpf_program__set_type(prog, prog_type); bpf_program__set_expected_attach_type(prog, expected_attach_type); - if (prog->idx != obj->efile.text_shndx && !first_prog) + if (!bpf_program__is_function_storage(prog, obj) && !first_prog) first_prog = prog; } bpf_map__for_each(map, obj) { - map->map_ifindex = attr->ifindex; + if (!bpf_map__is_offload_neutral(map)) + map->map_ifindex = attr->ifindex; } if (!first_prog) { diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h index 09976531aa74..1f8fc2060460 100644 --- a/tools/lib/bpf/libbpf.h +++ b/tools/lib/bpf/libbpf.h @@ -66,7 +66,13 @@ void libbpf_set_print(libbpf_print_fn_t warn, /* Hide internal to user */ struct bpf_object; +struct bpf_object_open_attr { + const char *file; + enum bpf_prog_type prog_type; +}; + struct bpf_object *bpf_object__open(const char *path); +struct bpf_object *bpf_object__open_xattr(struct bpf_object_open_attr *attr); struct bpf_object *bpf_object__open_buffer(void *obj_buf, size_t obj_buf_sz, const char *name); @@ -92,6 +98,9 @@ int bpf_object__set_priv(struct bpf_object *obj, void *priv, bpf_object_clear_priv_t clear_priv); void *bpf_object__priv(struct bpf_object *prog); +int libbpf_prog_type_by_name(const char *name, enum bpf_prog_type *prog_type, + enum bpf_attach_type *expected_attach_type); + /* Accessors of bpf_program */ struct bpf_program; struct bpf_program *bpf_program__next(struct bpf_program *prog, @@ -109,6 +118,7 @@ int bpf_program__set_priv(struct bpf_program *prog, void *priv, bpf_program_clear_priv_t clear_priv); void *bpf_program__priv(struct bpf_program *prog); +void bpf_program__set_ifindex(struct bpf_program *prog, __u32 ifindex); const char *bpf_program__title(struct bpf_program *prog, bool needs_copy); @@ -251,6 +261,9 @@ typedef void (*bpf_map_clear_priv_t)(struct bpf_map *, void *); int bpf_map__set_priv(struct bpf_map *map, void *priv, bpf_map_clear_priv_t clear_priv); void *bpf_map__priv(struct bpf_map *map); +int bpf_map__reuse_fd(struct bpf_map *map, int fd); +bool bpf_map__is_offload_neutral(struct bpf_map *map); +void bpf_map__set_ifindex(struct bpf_map *map, __u32 ifindex); int bpf_map__pin(struct bpf_map *map, const char *path); long libbpf_get_error(const void *ptr); diff --git a/tools/lib/bpf/libbpf_errno.c b/tools/lib/bpf/libbpf_errno.c new file mode 100644 index 000000000000..d9ba851bd7f9 --- /dev/null +++ b/tools/lib/bpf/libbpf_errno.c @@ -0,0 +1,74 @@ +// SPDX-License-Identifier: LGPL-2.1 + +/* + * Copyright (C) 2013-2015 Alexei Starovoitov <ast@kernel.org> + * Copyright (C) 2015 Wang Nan <wangnan0@huawei.com> + * Copyright (C) 2015 Huawei Inc. + * Copyright (C) 2017 Nicira, Inc. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; + * version 2.1 of the License (not later!) + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this program; if not, see <http://www.gnu.org/licenses> + */ + +#include <stdio.h> +#include <string.h> + +#include "libbpf.h" + +#define ERRNO_OFFSET(e) ((e) - __LIBBPF_ERRNO__START) +#define ERRCODE_OFFSET(c) ERRNO_OFFSET(LIBBPF_ERRNO__##c) +#define NR_ERRNO (__LIBBPF_ERRNO__END - __LIBBPF_ERRNO__START) + +static const char *libbpf_strerror_table[NR_ERRNO] = { + [ERRCODE_OFFSET(LIBELF)] = "Something wrong in libelf", + [ERRCODE_OFFSET(FORMAT)] = "BPF object format invalid", + [ERRCODE_OFFSET(KVERSION)] = "'version' section incorrect or lost", + [ERRCODE_OFFSET(ENDIAN)] = "Endian mismatch", + [ERRCODE_OFFSET(INTERNAL)] = "Internal error in libbpf", + [ERRCODE_OFFSET(RELOC)] = "Relocation failed", + [ERRCODE_OFFSET(VERIFY)] = "Kernel verifier blocks program loading", + [ERRCODE_OFFSET(PROG2BIG)] = "Program too big", + [ERRCODE_OFFSET(KVER)] = "Incorrect kernel version", + [ERRCODE_OFFSET(PROGTYPE)] = "Kernel doesn't support this program type", + [ERRCODE_OFFSET(WRNGPID)] = "Wrong pid in netlink message", + [ERRCODE_OFFSET(INVSEQ)] = "Invalid netlink sequence", +}; + +int libbpf_strerror(int err, char *buf, size_t size) +{ + if (!buf || !size) + return -1; + + err = err > 0 ? err : -err; + + if (err < __LIBBPF_ERRNO__START) { + int ret; + + ret = strerror_r(err, buf, size); + buf[size - 1] = '\0'; + return ret; + } + + if (err < __LIBBPF_ERRNO__END) { + const char *msg; + + msg = libbpf_strerror_table[ERRNO_OFFSET(err)]; + snprintf(buf, size, "%s", msg); + buf[size - 1] = '\0'; + return 0; + } + + snprintf(buf, size, "Unknown libbpf error %d", err); + buf[size - 1] = '\0'; + return -1; +} |