From d7cae0a753c49abead5eb0d241bfe8a0d311d54a Mon Sep 17 00:00:00 2001
From: david <david@e0a8ed71-7df4-0310-8962-fdc924857419>
Date: Sat, 7 Nov 2009 02:03:07 +0000
Subject: [PATCH] Fix the test for an IPv4 packet in readip_pcap. It was
 checking this condition: 	(*p & 0x40) == 0x40 But that doesn't check
 that the upper half of the byte is 4. It's true for 4, 5, 6, 7, 12, 13, 14,
 and 15. I changed it to 	(*p & 0xF0) == 0x40

---
 tcpip.cc | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tcpip.cc b/tcpip.cc
index 860d527ff..8211c7197 100644
--- a/tcpip.cc
+++ b/tcpip.cc
@@ -2342,7 +2342,7 @@ char *readip_pcap(pcap_t *pd, unsigned int *len, long to_usec,
       }
       p += offset;
     }
-    if (!p || (*p & 0x40) != 0x40) {
+    if (!p || (*p & 0xF0) != 0x40) {
       /* Should we timeout? */
       if (to_usec == 0) {
         timedout = 1;
@@ -2353,7 +2353,7 @@ char *readip_pcap(pcap_t *pd, unsigned int *len, long to_usec,
         }
       }
     }
-  } while (!timedout && (!p || (*p & 0x40) != 0x40)); /* Go until we get IPv4 packet */
+  } while (!timedout && (!p || (*p & 0xF0) != 0x40)); /* Go until we get IPv4 packet */
 
   if (timedout) {
     *len = 0;