Merge pull request appneta#247 from dsrana1212/master

fragroute fix to support fragmentation of IP datagrams that contain IP Total Length a 0 in header
baigubulu · May 13, 2016 · 41be9ba · 41be9ba
2 parents f330786 + 1eaab22
commit 41be9ba
Showing 1 changed file with 11 additions and 1 deletion.
diff --git a/src/fragroute/pkt.c b/src/fragroute/pkt.c
@@ -120,8 +120,18 @@ pkt_decorate(struct pkt *pkt)
 		pkt->pkt_ip = NULL;
 		return;
 	}
-	/* If IP length is longer than packet length, stop. */
+
 	len = ntohs(pkt->pkt_ip->ip_len);
+
+	  /* If IP length is 0, this packet was generated by wireshark 
+	   on systems with TCP Segmentation offloading to NIC enabled. 
+       Calculate the IP length from packet end and packet data pointers.
+	*/
+   	if (0 == len)
+        	len = (pkt->pkt_end - (pkt->pkt_data + ETH_HDR_LEN));
+
+	/* If IP length is longer than packet length, stop. 
+	*/
 	if (p + len > pkt->pkt_end)
 		return;