Patch by Steve Kemp <skx@debian.org> for dsniff >= 2.4b1, which adds a fix
to work with multiple interfaces. For further information, please have a
look to Debian bug ID #242369.

--- dsniff-2.4b1/arp.c			2005-06-23 03:30:37.000000000 +0000
+++ dsniff-2.4b1/arp.c.multiple_intf	2005-06-23 04:09:05.000000000 +0000
@@ -39,7 +39,7 @@
 
 #ifdef BSD
 int
-arp_cache_lookup(in_addr_t ip, struct ether_addr *ether)
+arp_cache_lookup(in_addr_t ip, struct ether_addr *ether, const char* linf)
 {
 	int mib[6];
 	size_t len;
@@ -91,7 +91,7 @@
 #endif
 
 int
-arp_cache_lookup(in_addr_t ip, struct ether_addr *ether)
+arp_cache_lookup(in_addr_t ip, struct ether_addr *ether, const char* lif)
 {
 	int sock;
 	struct arpreq ar;
@@ -99,7 +99,7 @@
 	
 	memset((char *)&ar, 0, sizeof(ar));
 #ifdef __linux__
-	strncpy(ar.arp_dev, "eth0", sizeof(ar.arp_dev));   /* XXX - *sigh* */
+	strncpy(ar.arp_dev, lif, strlen(lif));
 #endif
 	sin = (struct sockaddr_in *)&ar.arp_pa;
 	sin->sin_family = AF_INET;
--- dsniff-2.4b1/arp.h			2005-06-23 03:30:37.000000000 +0000
+++ dsniff-2.4b1/arp.h.multiple_intf	2005-06-23 04:09:07.000000000 +0000
@@ -11,6 +11,6 @@
 #ifndef _ARP_H_
 #define _ARP_H_
 
-int	arp_cache_lookup(in_addr_t ip, struct ether_addr *ether);
+int	arp_cache_lookup(in_addr_t ip, struct ether_addr *ether, const char* linf);
 
 #endif /* _ARP_H_ */
--- dsniff-2.4b1/arpspoof.c		2005-06-23 03:30:37.000000000 +0000
+++ dsniff-2.4b1/arpspoof.c.mltpl_intf	2005-06-23 04:08:41.000000000 +0000
@@ -113,7 +113,7 @@
 	int i = 0;
 
 	do {
-		if (arp_cache_lookup(ip, mac) == 0)
+		if (arp_cache_lookup(ip, mac, intf) == 0)
 			return (1);
 #ifdef __linux__
 		/* XXX - force the kernel to arp. feh. */