diff options
Diffstat (limited to 'tools/lib/bpf/gen_loader.c')
| -rw-r--r-- | tools/lib/bpf/gen_loader.c | 47 |
1 files changed, 47 insertions, 0 deletions
diff --git a/tools/lib/bpf/gen_loader.c b/tools/lib/bpf/gen_loader.c index 113ae4abd345..6945dd99a846 100644 --- a/tools/lib/bpf/gen_loader.c +++ b/tools/lib/bpf/gen_loader.c @@ -110,6 +110,7 @@ static void emit2(struct bpf_gen *gen, struct bpf_insn insn1, struct bpf_insn in static int add_data(struct bpf_gen *gen, const void *data, __u32 size); static void emit_sys_close_blob(struct bpf_gen *gen, int blob_off); +static void emit_signature_match(struct bpf_gen *gen); void bpf_gen__init(struct bpf_gen *gen, int log_level, int nr_progs, int nr_maps) { @@ -152,6 +153,8 @@ void bpf_gen__init(struct bpf_gen *gen, int log_level, int nr_progs, int nr_maps /* R7 contains the error code from sys_bpf. Copy it into R0 and exit. */ emit(gen, BPF_MOV64_REG(BPF_REG_0, BPF_REG_7)); emit(gen, BPF_EXIT_INSN()); + if (OPTS_GET(gen->opts, gen_hash, false)) + emit_signature_match(gen); } static int add_data(struct bpf_gen *gen, const void *data, __u32 size) @@ -368,6 +371,8 @@ static void emit_sys_close_blob(struct bpf_gen *gen, int blob_off) __emit_sys_close(gen); } +static void compute_sha_update_offsets(struct bpf_gen *gen); + int bpf_gen__finish(struct bpf_gen *gen, int nr_progs, int nr_maps) { int i; @@ -394,6 +399,9 @@ int bpf_gen__finish(struct bpf_gen *gen, int nr_progs, int nr_maps) blob_fd_array_off(gen, i)); emit(gen, BPF_MOV64_IMM(BPF_REG_0, 0)); emit(gen, BPF_EXIT_INSN()); + if (OPTS_GET(gen->opts, gen_hash, false)) + compute_sha_update_offsets(gen); + pr_debug("gen: finish %s\n", errstr(gen->error)); if (!gen->error) { struct gen_loader_opts *opts = gen->opts; @@ -446,6 +454,22 @@ void bpf_gen__free(struct bpf_gen *gen) _val; \ }) +static void compute_sha_update_offsets(struct bpf_gen *gen) +{ + __u64 sha[SHA256_DWORD_SIZE]; + __u64 sha_dw; + int i; + + libbpf_sha256(gen->data_start, gen->data_cur - gen->data_start, (__u8 *)sha); + for (i = 0; i < SHA256_DWORD_SIZE; i++) { + struct bpf_insn *insn = + (struct bpf_insn *)(gen->insn_start + gen->hash_insn_offset[i]); + sha_dw = tgt_endian(sha[i]); + insn[0].imm = (__u32)sha_dw; + insn[1].imm = sha_dw >> 32; + } +} + void bpf_gen__load_btf(struct bpf_gen *gen, const void *btf_raw_data, __u32 btf_raw_size) { @@ -557,6 +581,29 @@ void bpf_gen__map_create(struct bpf_gen *gen, emit_sys_close_stack(gen, stack_off(inner_map_fd)); } +static void emit_signature_match(struct bpf_gen *gen) +{ + __s64 off; + int i; + + for (i = 0; i < SHA256_DWORD_SIZE; i++) { + emit2(gen, BPF_LD_IMM64_RAW_FULL(BPF_REG_1, BPF_PSEUDO_MAP_IDX, + 0, 0, 0, 0)); + emit(gen, BPF_LDX_MEM(BPF_DW, BPF_REG_2, BPF_REG_1, i * sizeof(__u64))); + gen->hash_insn_offset[i] = gen->insn_cur - gen->insn_start; + emit2(gen, BPF_LD_IMM64_RAW_FULL(BPF_REG_3, 0, 0, 0, 0, 0)); + + off = -(gen->insn_cur - gen->insn_start - gen->cleanup_label) / 8 - 1; + if (is_simm16(off)) { + emit(gen, BPF_MOV64_IMM(BPF_REG_7, -EINVAL)); + emit(gen, BPF_JMP_REG(BPF_JNE, BPF_REG_2, BPF_REG_3, off)); + } else { + gen->error = -ERANGE; + emit(gen, BPF_JMP_IMM(BPF_JA, 0, 0, -1)); + } + } +} + void bpf_gen__record_attach_target(struct bpf_gen *gen, const char *attach_name, enum bpf_attach_type type) { |