[RFC PATCH bpf-next 3/5] libbpf: Add link support for BPF_PROG_TYPE_SK_MSG

[Yonghong Song <yonghong.song@linux.dev>]

Introduce a libbpf API bpf_program__attach_sk_msg() which allows
user to get a bpf_link. The API makes auto-deletion easier and
also allows user space application easier as link based APIs
are used for all programs.

Signed-off-by: Yonghong Song <yonghong.song@linux.dev>
---
 tools/lib/bpf/libbpf.c   | 8 ++++++++
 tools/lib/bpf/libbpf.h   | 3 +++
 tools/lib/bpf/libbpf.map | 1 +
 3 files changed, 12 insertions(+)

diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 97b573516675..b3982bb3f979 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -149,6 +149,7 @@ static const char * const link_type_name[] = {
 	[BPF_LINK_TYPE_TCX]			= "tcx",
 	[BPF_LINK_TYPE_UPROBE_MULTI]		= "uprobe_multi",
 	[BPF_LINK_TYPE_NETKIT]			= "netkit",
+	[BPF_LINK_TYPE_SK_MSG]			= "sk_msg",
 };
 
 static const char * const map_type_name[] = {
@@ -12280,6 +12281,13 @@ bpf_program__attach_netkit(const struct bpf_program *prog, int ifindex,
 	return bpf_program_attach_fd(prog, ifindex, "netkit", &link_create_opts);
 }
 
+struct bpf_link *
+bpf_program__attach_sk_msg(const struct bpf_program *prog, int map_fd,
+			   enum bpf_attach_type attach_type)
+{
+	return __bpf_program_attach_fd(prog, map_fd, attach_type, "sk_msg", NULL);
+}
+
 struct bpf_link *bpf_program__attach_freplace(const struct bpf_program *prog,
 					      int target_fd,
 					      const char *attach_func_name)
diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h
index 5723cbbfcc41..c8448f05e8d6 100644
--- a/tools/lib/bpf/libbpf.h
+++ b/tools/lib/bpf/libbpf.h
@@ -786,6 +786,9 @@ bpf_program__attach_netns(const struct bpf_program *prog, int netns_fd);
 LIBBPF_API struct bpf_link *
 bpf_program__attach_xdp(const struct bpf_program *prog, int ifindex);
 LIBBPF_API struct bpf_link *
+bpf_program__attach_sk_msg(const struct bpf_program *prog, int map_fd,
+			   enum bpf_attach_type attach_type);
+LIBBPF_API struct bpf_link *
 bpf_program__attach_freplace(const struct bpf_program *prog,
 			     int target_fd, const char *attach_func_name);
 
diff --git a/tools/lib/bpf/libbpf.map b/tools/lib/bpf/libbpf.map
index 86804fd90dd1..c59986c6dbc5 100644
--- a/tools/lib/bpf/libbpf.map
+++ b/tools/lib/bpf/libbpf.map
@@ -410,6 +410,7 @@ LIBBPF_1.3.0 {
 
 LIBBPF_1.4.0 {
 	global:
+		bpf_program__attach_sk_msg;
 		bpf_token_create;
 		btf__new_split;
 		btf_ext__raw_data;
-- 
2.43.0