bpf: Add bpf_skc_to_unix_sock() helper

[linux-2.6-block.git] / net / core / filter.c

diff --git a/net/core/filter.c b/net/core/filter.c
index 4bace37a6a4495204b25c6fb2c9da2299e15e4c1..8e8d3b49c2976725cd37baa9cbecd2d4e6f66019 100644 (file)
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -10723,6 +10723,26 @@ const struct bpf_func_proto bpf_skc_to_udp6_sock_proto = {
        .ret_btf_id             = &btf_sock_ids[BTF_SOCK_TYPE_UDP6],
 };
 
+BPF_CALL_1(bpf_skc_to_unix_sock, struct sock *, sk)
+{
+       /* unix_sock type is not generated in dwarf and hence btf,
+        * trigger an explicit type generation here.
+        */
+       BTF_TYPE_EMIT(struct unix_sock);
+       if (sk && sk_fullsock(sk) && sk->sk_family == AF_UNIX)
+               return (unsigned long)sk;
+
+       return (unsigned long)NULL;
+}
+
+const struct bpf_func_proto bpf_skc_to_unix_sock_proto = {
+       .func                   = bpf_skc_to_unix_sock,
+       .gpl_only               = false,
+       .ret_type               = RET_PTR_TO_BTF_ID_OR_NULL,
+       .arg1_type              = ARG_PTR_TO_BTF_ID_SOCK_COMMON,
+       .ret_btf_id             = &btf_sock_ids[BTF_SOCK_TYPE_UNIX],
+};
+
 BPF_CALL_1(bpf_sock_from_file, struct file *, file)
 {
        return (unsigned long)sock_from_file(file);
@@ -10762,6 +10782,9 @@ bpf_sk_base_func_proto(enum bpf_func_id func_id)
        case BPF_FUNC_skc_to_udp6_sock:
                func = &bpf_skc_to_udp6_sock_proto;
                break;
+       case BPF_FUNC_skc_to_unix_sock:
+               func = &bpf_skc_to_unix_sock_proto;
+               break;
        default:
                return bpf_base_func_proto(func_id);
        }