[PATCH v4 net-next 1/4] libbpf: add ability to guess program type based on section name
From: Roman Gushchin <hidden>
Date: 2017-12-13 15:19:47
Also in:
lkml
Subsystem:
bpf [general] (safe dynamic programs and tools), bpf [library] (libbpf), the rest · Maintainers:
Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Eduard Zingerman, Kumar Kartikeya Dwivedi, Linus Torvalds
The bpf_prog_load() function will guess program type if it's not specified explicitly. This functionality will be used to implement loading of different programs without asking a user to specify the program type. In first order it will be used by bpftool. Signed-off-by: Roman Gushchin <redacted> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Jakub Kicinski <redacted> Cc: Martin KaFai Lau <redacted> Cc: Quentin Monnet <redacted> Cc: David Ahern <redacted> --- tools/lib/bpf/libbpf.c | 51 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 51 insertions(+)
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 5aa45f89da93..205b7822fa0a 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c@@ -1721,6 +1721,45 @@ BPF_PROG_TYPE_FNS(tracepoint, BPF_PROG_TYPE_TRACEPOINT); BPF_PROG_TYPE_FNS(xdp, BPF_PROG_TYPE_XDP); BPF_PROG_TYPE_FNS(perf_event, BPF_PROG_TYPE_PERF_EVENT); +#define BPF_PROG_SEC(string, type) { string, sizeof(string), type } +static const struct { + const char *sec; + size_t len; + enum bpf_prog_type prog_type; +} section_names[] = { + BPF_PROG_SEC("socket", BPF_PROG_TYPE_SOCKET_FILTER), + BPF_PROG_SEC("kprobe/", BPF_PROG_TYPE_KPROBE), + BPF_PROG_SEC("kretprobe/", BPF_PROG_TYPE_KPROBE), + BPF_PROG_SEC("tracepoint/", BPF_PROG_TYPE_TRACEPOINT), + BPF_PROG_SEC("xdp", BPF_PROG_TYPE_XDP), + BPF_PROG_SEC("perf_event", BPF_PROG_TYPE_PERF_EVENT), + BPF_PROG_SEC("cgroup/skb", BPF_PROG_TYPE_CGROUP_SKB), + BPF_PROG_SEC("cgroup/sock", BPF_PROG_TYPE_CGROUP_SOCK), + BPF_PROG_SEC("cgroup/dev", BPF_PROG_TYPE_CGROUP_DEVICE), + BPF_PROG_SEC("sockops", BPF_PROG_TYPE_SOCK_OPS), + BPF_PROG_SEC("sk_skb", BPF_PROG_TYPE_SK_SKB), +}; +#undef BPF_PROG_SEC + +static enum bpf_prog_type bpf_program__guess_type(struct bpf_program *prog) +{ + 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 section_names[i].prog_type; + +err: + pr_warning("failed to guess program type based on section name %s\n", + prog->section_name); + + return BPF_PROG_TYPE_UNSPEC; +} + int bpf_map__fd(struct bpf_map *map) { return map ? map->fd : -EINVAL;
@@ -1832,6 +1871,18 @@ int bpf_prog_load(const char *file, enum bpf_prog_type type, return -ENOENT; } + /* + * If type is not specified, try to guess it based on + * section name. + */ + if (type == BPF_PROG_TYPE_UNSPEC) { + type = bpf_program__guess_type(prog); + if (type == BPF_PROG_TYPE_UNSPEC) { + bpf_object__close(obj); + return -EINVAL; + } + } + bpf_program__set_type(prog, type); err = bpf_object__load(obj); if (err) {
--
2.14.3