diff --git a/include/osmocom/core/socket.h b/include/osmocom/core/socket.h
index d2118ef..6db436a 100644
--- a/include/osmocom/core/socket.h
+++ b/include/osmocom/core/socket.h
@@ -8,6 +8,7 @@
  *  \file socket.h */
 
 #include <stdint.h>
+#include <stdbool.h>
 
 struct sockaddr;
 struct osmo_fd;
@@ -47,4 +48,9 @@
 
 char *osmo_sock_get_name(void *ctx, int fd);
 
+int osmo_sock_mcast_loop_set(int fd, bool enable);
+int osmo_sock_mcast_ttl_set(int fd, uint8_t ttl);
+int osmo_sock_mcast_all_set(int fd, bool enable);
+int osmo_sock_mcast_subscribe(int fd, const char *grp_addr);
+
 /*! @} */