bpf: Enable retrieval of socket cookie for bind/post-bind hook

We currently make heavy use of the socket cookie in BPF's connect(),
sendmsg() and recvmsg() hooks for load-balancing decisions. However,
it is currently not enabled/implemented in BPF {post-}bind hooks
where it can later be used in combination for correlation in the tc
egress path, for example.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/e9d71f310715332f12d238cc650c1edc5be55119.1585323121.git.daniel@iogearbox.net

diff --git a/net/core/filter.c b/net/core/filter.c
index 96350a7..0b66825 100644 (file)
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -4117,6 +4117,18 @@ static const struct bpf_func_proto bpf_get_socket_cookie_sock_addr_proto = {
        .arg1_type      = ARG_PTR_TO_CTX,
 };
 
+BPF_CALL_1(bpf_get_socket_cookie_sock, struct sock *, ctx)
+{
+       return sock_gen_cookie(ctx);
+}
+
+static const struct bpf_func_proto bpf_get_socket_cookie_sock_proto = {
+       .func           = bpf_get_socket_cookie_sock,
+       .gpl_only       = false,
+       .ret_type       = RET_INTEGER,
+       .arg1_type      = ARG_PTR_TO_CTX,
+};
+
 BPF_CALL_1(bpf_get_socket_cookie_sock_ops, struct bpf_sock_ops_kern *, ctx)
 {
        return sock_gen_cookie(ctx->sk);
@@ -5954,6 +5966,8 @@ sock_filter_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
                return &bpf_get_current_uid_gid_proto;
        case BPF_FUNC_get_local_storage:
                return &bpf_get_local_storage_proto;
+       case BPF_FUNC_get_socket_cookie:
+               return &bpf_get_socket_cookie_sock_proto;
        default:
                return bpf_base_func_proto(func_id);
        }