From: guy <guy>
Date: Fri, 25 Jun 2004 01:21:06 +0000 (+0000)
Subject: From Eddie Kohler <xexd@sourceforge.net>: In "ip_finddst()":
X-Git-Url: https://git.tcpdump.org/tcpdump/commitdiff_plain/c451929916521bca3280b171fff52d1e2caba54b

From Eddie Kohler <xexd@sourceforge.net>: In "ip_finddst()":

	quit as soon as we see IPOPT_EOL;

	*don't* quit as soon as we see IPOPT_NOP, just advance to the
	next option, if any;

	implement "quit" as "return the destination address from the IP
	header rather than as "return 0".

Also, return the IP header destination address if we see a
source-routing option with a too-short length.
---

diff --git a/CREDITS b/CREDITS
index 57680532..b8f572ae 100644
--- a/CREDITS
+++ b/CREDITS
@@ -33,6 +33,7 @@ Additional people who have contributed patches:
 	Darren Reed			<darrenr@reed.wattle.id.au>
 	David Binderman			<d.binderman@virgin.net>
 	David Young			<dyoung@ojctech.com>
+	Eddie Kohler			<xexd@sourceforge.net>
 	Francis Dupont			<Francis.Dupont@enst-bretagne.fr>
 	Francisco Matias Cuenca-Acuna	<mcuenca@george.rutgers.edu>
 	Frank Volf			<volf@oasis.IAEhv.nl>
diff --git a/print-ip.c b/print-ip.c
index 4773d363..8422f0d9 100644
--- a/print-ip.c
+++ b/print-ip.c
@@ -21,7 +21,7 @@
 
 #ifndef lint
 static const char rcsid[] _U_ =
-    "@(#) $Header: /tcpdump/master/tcpdump/print-ip.c,v 1.128.2.6 2004-03-24 09:01:39 guy Exp $ (LBL)";
+    "@(#) $Header: /tcpdump/master/tcpdump/print-ip.c,v 1.128.2.7 2004-06-25 01:21:06 guy Exp $ (LBL)";
 #endif
 
 #ifdef HAVE_CONFIG_H
@@ -72,7 +72,7 @@ ip_printroute(const char *type, register const u_char *cp, u_int length)
 }
 
 /*
- * If source-routing is present, return the final destination.
+ * If source-routing is present and valid, return the final destination.
  * Otherwise, return IP destination.
  *
  * This is used for UDP and TCP pseudo-header in the checksum
@@ -94,14 +94,15 @@ ip_finddst(const struct ip *ip)
 
 		TCHECK(*cp);
 		tt = *cp;
-		if (tt == IPOPT_NOP || tt == IPOPT_EOL)
+		if (tt == IPOPT_EOL)
+			break;
+		else if (tt == IPOPT_NOP)
 			len = 1;
 		else {
 			TCHECK(cp[1]);
 			len = cp[1];
-		}
-		if (len < 2) {
-			return 0;
+			if (len < 2)
+				break;
 		}
 		TCHECK2(*cp, len);
 		switch (tt) {
@@ -109,15 +110,14 @@ ip_finddst(const struct ip *ip)
 		case IPOPT_SSRR:
 		case IPOPT_LSRR:
 			if (len < 7)
-				return 0;
+				break;
 			memcpy(&retval, cp + len - 4, 4);
 			return retval;
 		}
 	}
-	return ip->ip_dst.s_addr;
-
 trunc:
-	return 0;
+	memcpy(&retval, &ip->ip_dst.s_addr, sizeof(u_int32_t));
+	return retval;
 }
 
 static void