libbpf: add ability to guess program type based on section name

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 <guro@fb.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Jakub Kicinski <jakub.kicinski@netronome.com>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Quentin Monnet <quentin.monnet@netronome.com>
Cc: David Ahern <dsahern@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
This commit is contained in:
Roman Gushchin 2017-12-13 15:18:51 +00:00 committed by Daniel Borkmann
parent f4e2298e63
commit 583c90097f

View File

@ -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(xdp, BPF_PROG_TYPE_XDP);
BPF_PROG_TYPE_FNS(perf_event, BPF_PROG_TYPE_PERF_EVENT); 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) int bpf_map__fd(struct bpf_map *map)
{ {
return map ? map->fd : -EINVAL; return map ? map->fd : -EINVAL;
@ -1832,6 +1871,18 @@ int bpf_prog_load(const char *file, enum bpf_prog_type type,
return -ENOENT; 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); bpf_program__set_type(prog, type);
err = bpf_object__load(obj); err = bpf_object__load(obj);
if (err) { if (err) {