1 files changed, 1 insertions, 0 deletions
diff --git a/udp.h b/udp.h
index 90968cd..79cf3a2 100644
--- a/udp.h
+++ b/udp.h
@@ -1,4 +1,5 @@
 #ifndef _UDP_H
 #define _UDP_H 1
 extern int send_custom_udp(const int socket, const int ifindex, const unsigned char *sourcemac, const unsigned char *destmac, const struct in_addr *sourceip, const int sourceport, const struct in_addr *destip, const int destport, const unsigned char *data, const int datalen);
+extern unsigned short in_cksum(unsigned short *addr, int len);
 #endif