diff options
Diffstat (limited to 'tools/lib/bpf/libbpf.c')
| -rw-r--r-- | tools/lib/bpf/libbpf.c | 69 |
1 files changed, 69 insertions, 0 deletions
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index a39640bd5448..5161c2b39875 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -499,6 +499,7 @@ struct bpf_program { __u32 line_info_rec_size; __u32 line_info_cnt; __u32 prog_flags; + __u8 hash[SHA256_DIGEST_LENGTH]; }; struct bpf_struct_ops { @@ -578,6 +579,7 @@ struct bpf_map { bool autocreate; bool autoattach; __u64 map_extra; + struct bpf_program *excl_prog; }; enum extern_type { @@ -4488,6 +4490,44 @@ bpf_object__section_to_libbpf_map_type(const struct bpf_object *obj, int shndx) } } +static int bpf_prog_compute_hash(struct bpf_program *prog) +{ + struct bpf_insn *purged; + int i, err; + + purged = calloc(prog->insns_cnt, BPF_INSN_SZ); + if (!purged) + return -ENOMEM; + + /* If relocations have been done, the map_fd needs to be + * discarded for the digest calculation. + */ + for (i = 0; i < prog->insns_cnt; i++) { + purged[i] = prog->insns[i]; + if (purged[i].code == (BPF_LD | BPF_IMM | BPF_DW) && + (purged[i].src_reg == BPF_PSEUDO_MAP_FD || + purged[i].src_reg == BPF_PSEUDO_MAP_VALUE)) { + purged[i].imm = 0; + i++; + if (i >= prog->insns_cnt || + prog->insns[i].code != 0 || + prog->insns[i].dst_reg != 0 || + prog->insns[i].src_reg != 0 || + prog->insns[i].off != 0) { + err = -EINVAL; + goto out; + } + purged[i] = prog->insns[i]; + purged[i].imm = 0; + } + } + err = libbpf_sha256(purged, prog->insns_cnt * sizeof(struct bpf_insn), + prog->hash, SHA256_DIGEST_LENGTH); +out: + free(purged); + return err; +} + static int bpf_program__record_reloc(struct bpf_program *prog, struct reloc_desc *reloc_desc, __u32 insn_idx, const char *sym_name, @@ -5237,6 +5277,14 @@ static int bpf_object__create_map(struct bpf_object *obj, struct bpf_map *map, b create_attr.token_fd = obj->token_fd; if (obj->token_fd) create_attr.map_flags |= BPF_F_TOKEN_FD; + if (map->excl_prog) { + err = bpf_prog_compute_hash(map->excl_prog); + if (err) + return err; + + create_attr.excl_prog_hash = map->excl_prog->hash; + create_attr.excl_prog_hash_size = SHA256_DIGEST_LENGTH; + } if (bpf_map__is_struct_ops(map)) { create_attr.btf_vmlinux_value_type_id = map->btf_vmlinux_value_type_id; @@ -10527,6 +10575,27 @@ int bpf_map__set_inner_map_fd(struct bpf_map *map, int fd) return 0; } +int bpf_map__set_exclusive_program(struct bpf_map *map, struct bpf_program *prog) +{ + if (map_is_created(map)) { + pr_warn("exclusive programs must be set before map creation\n"); + return libbpf_err(-EINVAL); + } + + if (map->obj != prog->obj) { + pr_warn("excl_prog and map must be from the same bpf object\n"); + return libbpf_err(-EINVAL); + } + + map->excl_prog = prog; + return 0; +} + +struct bpf_program *bpf_map__exclusive_program(struct bpf_map *map) +{ + return map->excl_prog; +} + static struct bpf_map * __bpf_map__iter(const struct bpf_map *m, const struct bpf_object *obj, int i) { |