diff --git a/include/ip2string.h b/include/ip2string.h
index 0753ee82a94..4c5f36c15f6 100644
--- a/include/ip2string.h
+++ b/include/ip2string.h
@@ -23,6 +23,13 @@
 extern "C" {
 #endif
 
+char * WINAPI RtlIpv4AddressToStringA(const IN_ADDR *address, char *str);
+WCHAR * WINAPI RtlIpv4AddressToStringW(const IN_ADDR *address, WCHAR *str);
+#define RtlIpv4AddressToString WINELIB_NAME_AW(RtlIpv4AddressToString)
+NTSTATUS WINAPI RtlIpv4AddressToStringExA(const IN_ADDR *address, USHORT port, char *str, ULONG *size);
+NTSTATUS WINAPI RtlIpv4AddressToStringExW(const IN_ADDR *address, USHORT port, WCHAR *str, ULONG *size);
+#define RtlIpv4AddressToStringEx WINELIB_NAME_AW(RtlIpv4AddressToStringEx)
+
 NTSTATUS WINAPI RtlIpv4StringToAddressA(const char *str, BOOLEAN strict, const char **terminator, IN_ADDR *address);
 NTSTATUS WINAPI RtlIpv4StringToAddressW(const WCHAR *str, BOOLEAN strict, const WCHAR **terminator, IN_ADDR *address);
 #define RtlIpv4StringToAddress WINELIB_NAME_AW(RtlIpv4StringToAddress)