diff --git a/libavformat/network.h b/libavformat/network.h
index d1f3d29455..07112ef7ef 100644
--- a/libavformat/network.h
+++ b/libavformat/network.h
@@ -155,4 +155,11 @@ const char *ff_gai_strerror(int ecode);
 #define INET6_ADDRSTRLEN INET_ADDRSTRLEN
 #endif
 
+#ifndef IN_MULTICAST
+#define IN_MULTICAST(a) ((((uint32_t)(a)) & 0xf0000000) == 0xe0000000)
+#endif
+#ifndef IN6_IS_ADDR_MULTICAST
+#define IN6_IS_ADDR_MULTICAST(a) (((uint8_t *) (a))[0] == 0xff)
+#endif
+
 #endif /* AVFORMAT_NETWORK_H */
diff --git a/libavformat/udp.c b/libavformat/udp.c
index 58fbe96c3f..c1160cf98c 100644
--- a/libavformat/udp.c
+++ b/libavformat/udp.c
@@ -40,12 +40,6 @@
 #define IPV6_ADD_MEMBERSHIP IPV6_JOIN_GROUP
 #define IPV6_DROP_MEMBERSHIP IPV6_LEAVE_GROUP
 #endif
-#ifndef IN_MULTICAST
-#define IN_MULTICAST(a) ((((uint32_t)(a)) & 0xf0000000) == 0xe0000000)
-#endif
-#ifndef IN6_IS_ADDR_MULTICAST
-#define IN6_IS_ADDR_MULTICAST(a) (((uint8_t *) (a))[0] == 0xff)
-#endif
 
 typedef struct {
     int udp_fd;