From 1e092a0318292637cde832868016f37e942eed24 Mon Sep 17 00:00:00 2001 From: KP Singh Date: Sun, 29 Mar 2020 01:43:54 +0100 Subject: tools/libbpf: Add support for BPF_PROG_TYPE_LSM Since BPF_PROG_TYPE_LSM uses the same attaching mechanism as BPF_PROG_TYPE_TRACING, the common logic is refactored into a static function bpf_program__attach_btf_id. A new API call bpf_program__attach_lsm is still added to avoid userspace conflicts if this ever changes in the future. Signed-off-by: KP Singh Signed-off-by: Daniel Borkmann Reviewed-by: Brendan Jackman Reviewed-by: Florent Revest Reviewed-by: James Morris Acked-by: Yonghong Song Acked-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20200329004356.27286-7-kpsingh@chromium.org --- tools/lib/bpf/bpf.c | 3 ++- tools/lib/bpf/libbpf.c | 39 +++++++++++++++++++++++++++++++++++---- tools/lib/bpf/libbpf.h | 4 ++++ tools/lib/bpf/libbpf.map | 3 +++ 4 files changed, 44 insertions(+), 5 deletions(-) (limited to 'tools/lib') diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c index c6dafe563176..73220176728d 100644 --- a/tools/lib/bpf/bpf.c +++ b/tools/lib/bpf/bpf.c @@ -235,7 +235,8 @@ int bpf_load_program_xattr(const struct bpf_load_program_attr *load_attr, memset(&attr, 0, sizeof(attr)); attr.prog_type = load_attr->prog_type; attr.expected_attach_type = load_attr->expected_attach_type; - if (attr.prog_type == BPF_PROG_TYPE_STRUCT_OPS) { + if (attr.prog_type == BPF_PROG_TYPE_STRUCT_OPS || + attr.prog_type == BPF_PROG_TYPE_LSM) { attr.attach_btf_id = load_attr->attach_btf_id; } else if (attr.prog_type == BPF_PROG_TYPE_TRACING || attr.prog_type == BPF_PROG_TYPE_EXT) { diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index 7deab98720ee..0638e717f502 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -2358,7 +2358,8 @@ static int bpf_object__finalize_btf(struct bpf_object *obj) static inline bool libbpf_prog_needs_vmlinux_btf(struct bpf_program *prog) { - if (prog->type == BPF_PROG_TYPE_STRUCT_OPS) + if (prog->type == BPF_PROG_TYPE_STRUCT_OPS || + prog->type == BPF_PROG_TYPE_LSM) return true; /* BPF_PROG_TYPE_TRACING programs which do not attach to other programs @@ -4866,7 +4867,8 @@ load_program(struct bpf_program *prog, struct bpf_insn *insns, int insns_cnt, load_attr.insns = insns; load_attr.insns_cnt = insns_cnt; load_attr.license = license; - if (prog->type == BPF_PROG_TYPE_STRUCT_OPS) { + if (prog->type == BPF_PROG_TYPE_STRUCT_OPS || + prog->type == BPF_PROG_TYPE_LSM) { load_attr.attach_btf_id = prog->attach_btf_id; } else if (prog->type == BPF_PROG_TYPE_TRACING || prog->type == BPF_PROG_TYPE_EXT) { @@ -4957,6 +4959,7 @@ int bpf_program__load(struct bpf_program *prog, char *license, __u32 kern_ver) int err = 0, fd, i, btf_id; if ((prog->type == BPF_PROG_TYPE_TRACING || + prog->type == BPF_PROG_TYPE_LSM || prog->type == BPF_PROG_TYPE_EXT) && !prog->attach_btf_id) { btf_id = libbpf_find_attach_btf_id(prog); if (btf_id <= 0) @@ -6196,6 +6199,7 @@ bool bpf_program__is_##NAME(const struct bpf_program *prog) \ } \ BPF_PROG_TYPE_FNS(socket_filter, BPF_PROG_TYPE_SOCKET_FILTER); +BPF_PROG_TYPE_FNS(lsm, BPF_PROG_TYPE_LSM); BPF_PROG_TYPE_FNS(kprobe, BPF_PROG_TYPE_KPROBE); BPF_PROG_TYPE_FNS(sched_cls, BPF_PROG_TYPE_SCHED_CLS); BPF_PROG_TYPE_FNS(sched_act, BPF_PROG_TYPE_SCHED_ACT); @@ -6262,6 +6266,8 @@ static struct bpf_link *attach_raw_tp(const struct bpf_sec_def *sec, struct bpf_program *prog); static struct bpf_link *attach_trace(const struct bpf_sec_def *sec, struct bpf_program *prog); +static struct bpf_link *attach_lsm(const struct bpf_sec_def *sec, + struct bpf_program *prog); struct bpf_sec_def { const char *sec; @@ -6312,6 +6318,10 @@ static const struct bpf_sec_def section_defs[] = { SEC_DEF("freplace/", EXT, .is_attach_btf = true, .attach_fn = attach_trace), + SEC_DEF("lsm/", LSM, + .is_attach_btf = true, + .expected_attach_type = BPF_LSM_MAC, + .attach_fn = attach_lsm), BPF_PROG_SEC("xdp", BPF_PROG_TYPE_XDP), BPF_PROG_SEC("perf_event", BPF_PROG_TYPE_PERF_EVENT), BPF_PROG_SEC("lwt_in", BPF_PROG_TYPE_LWT_IN), @@ -6574,6 +6584,7 @@ invalid_prog: } #define BTF_TRACE_PREFIX "btf_trace_" +#define BTF_LSM_PREFIX "bpf_lsm_" #define BTF_MAX_NAME_SIZE 128 static int find_btf_by_prefix_kind(const struct btf *btf, const char *prefix, @@ -6601,6 +6612,9 @@ static inline int __find_vmlinux_btf_id(struct btf *btf, const char *name, if (attach_type == BPF_TRACE_RAW_TP) err = find_btf_by_prefix_kind(btf, BTF_TRACE_PREFIX, name, BTF_KIND_TYPEDEF); + else if (attach_type == BPF_LSM_MAC) + err = find_btf_by_prefix_kind(btf, BTF_LSM_PREFIX, name, + BTF_KIND_FUNC); else err = btf__find_by_name_kind(btf, name, BTF_KIND_FUNC); @@ -7465,7 +7479,8 @@ static struct bpf_link *attach_raw_tp(const struct bpf_sec_def *sec, return bpf_program__attach_raw_tracepoint(prog, tp_name); } -struct bpf_link *bpf_program__attach_trace(struct bpf_program *prog) +/* Common logic for all BPF program types that attach to a btf_id */ +static struct bpf_link *bpf_program__attach_btf_id(struct bpf_program *prog) { char errmsg[STRERR_BUFSIZE]; struct bpf_link *link; @@ -7487,7 +7502,7 @@ struct bpf_link *bpf_program__attach_trace(struct bpf_program *prog) if (pfd < 0) { pfd = -errno; free(link); - pr_warn("program '%s': failed to attach to trace: %s\n", + pr_warn("program '%s': failed to attach: %s\n", bpf_program__title(prog, false), libbpf_strerror_r(pfd, errmsg, sizeof(errmsg))); return ERR_PTR(pfd); @@ -7496,12 +7511,28 @@ struct bpf_link *bpf_program__attach_trace(struct bpf_program *prog) return (struct bpf_link *)link; } +struct bpf_link *bpf_program__attach_trace(struct bpf_program *prog) +{ + return bpf_program__attach_btf_id(prog); +} + +struct bpf_link *bpf_program__attach_lsm(struct bpf_program *prog) +{ + return bpf_program__attach_btf_id(prog); +} + static struct bpf_link *attach_trace(const struct bpf_sec_def *sec, struct bpf_program *prog) { return bpf_program__attach_trace(prog); } +static struct bpf_link *attach_lsm(const struct bpf_sec_def *sec, + struct bpf_program *prog) +{ + return bpf_program__attach_lsm(prog); +} + struct bpf_link *bpf_program__attach(struct bpf_program *prog) { const struct bpf_sec_def *sec_def; diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h index 958ae71c116e..55348724c355 100644 --- a/tools/lib/bpf/libbpf.h +++ b/tools/lib/bpf/libbpf.h @@ -248,6 +248,8 @@ bpf_program__attach_raw_tracepoint(struct bpf_program *prog, LIBBPF_API struct bpf_link * bpf_program__attach_trace(struct bpf_program *prog); +LIBBPF_API struct bpf_link * +bpf_program__attach_lsm(struct bpf_program *prog); struct bpf_map; LIBBPF_API struct bpf_link *bpf_map__attach_struct_ops(struct bpf_map *map); struct bpf_insn; @@ -321,6 +323,7 @@ LIBBPF_API int bpf_program__set_socket_filter(struct bpf_program *prog); LIBBPF_API int bpf_program__set_tracepoint(struct bpf_program *prog); LIBBPF_API int bpf_program__set_raw_tracepoint(struct bpf_program *prog); LIBBPF_API int bpf_program__set_kprobe(struct bpf_program *prog); +LIBBPF_API int bpf_program__set_lsm(struct bpf_program *prog); LIBBPF_API int bpf_program__set_sched_cls(struct bpf_program *prog); LIBBPF_API int bpf_program__set_sched_act(struct bpf_program *prog); LIBBPF_API int bpf_program__set_xdp(struct bpf_program *prog); @@ -347,6 +350,7 @@ LIBBPF_API bool bpf_program__is_socket_filter(const struct bpf_program *prog); LIBBPF_API bool bpf_program__is_tracepoint(const struct bpf_program *prog); LIBBPF_API bool bpf_program__is_raw_tracepoint(const struct bpf_program *prog); LIBBPF_API bool bpf_program__is_kprobe(const struct bpf_program *prog); +LIBBPF_API bool bpf_program__is_lsm(const struct bpf_program *prog); LIBBPF_API bool bpf_program__is_sched_cls(const struct bpf_program *prog); LIBBPF_API bool bpf_program__is_sched_act(const struct bpf_program *prog); LIBBPF_API bool bpf_program__is_xdp(const struct bpf_program *prog); diff --git a/tools/lib/bpf/libbpf.map b/tools/lib/bpf/libbpf.map index 159826b36b38..eabd3d3e689f 100644 --- a/tools/lib/bpf/libbpf.map +++ b/tools/lib/bpf/libbpf.map @@ -244,6 +244,9 @@ LIBBPF_0.0.8 { bpf_link__pin_path; bpf_link__unpin; bpf_map__set_initial_value; + bpf_program__attach_lsm; + bpf_program__is_lsm; bpf_program__set_attach_target; + bpf_program__set_lsm; bpf_set_link_xdp_fd_opts; } LIBBPF_0.0.7; -- cgit v1.2.3