# 
# Patch for OpenBSD's ifconfig that should
# allow changing of link-layer address for a given
# interface (eg. MAC address on Ethernet).
# Adapted by Michal Ludvig <michal@logix.cz>
# See http://www.logix.cz/michal/devel/openbsd-lladdr/ for more info.
# 
Index: ifconfig.8
===================================================================
RCS file: /cvs/src/sbin/ifconfig/ifconfig.8,v
retrieving revision 1.59
diff -u -p -r1.59 ifconfig.8
--- ifconfig.8	14 Nov 2002 02:57:27 -0000	1.59
+++ ifconfig.8	15 Nov 2002 09:23:51 -0000
@@ -238,6 +238,16 @@ for some Ethernet cards.
 Refer to the man page for the specific driver for more information.
 .It Fl link[0-2]
 Disable special processing at the link level with the specified interface.
+.It Cm lladdr Ar hwaddr
+Set the link-level address on an interface. This can be used to
+e.g. set a new MAC address on an ethernet interface, though the
+mechanism used is not ethernet-specific. The address
+.Ar hwaddr
+is specified as a series of colon-separated hex digits.
+If the interface is already up when this option is used, it will be 
+briefly brought down and then brought back up again in order 
+to insure that the receive filter in the underlying ethernet 
+hardware is properly reprogrammed.
 .It Cm media Ar type
 Set the media type of the interface to
 .Ar type .
Index: ifconfig.c
===================================================================
RCS file: /cvs/src/sbin/ifconfig/ifconfig.c,v
retrieving revision 1.69
diff -u -p -r1.69 ifconfig.c
--- ifconfig.c	8 Jul 2002 00:48:54 -0000	1.69
+++ ifconfig.c	15 Nov 2002 09:23:52 -0000
@@ -171,6 +171,7 @@ void	setifbroadaddr(char *);
 void	setifipdst(char *);
 void	setifmetric(char *);
 void	setifmtu(char *, int);
+void    setiflladdr(char *, int);
 void	setifnwid(const char *, int);
 void	setifnwkey(const char *, int);
 void	setifpowersave(const char *, int);
@@ -251,6 +252,7 @@ const struct	cmd {
 	{ "netmask",	NEXTARG,	0,		setifnetmask },
 	{ "metric",	NEXTARG,	0,		setifmetric },
 	{ "mtu",	NEXTARG,	0,		setifmtu },
+	{ "lladdr",	NEXTARG,	0,		setiflladdr },
 	{ "nwid",	NEXTARG,	0,		setifnwid },
 	{ "nwkey",	NEXTARG,	0,		setifnwkey },
 	{ "-nwkey",	-1,		0,		setifnwkey },
@@ -1034,6 +1036,28 @@ setifmtu(val, d)
 		warn("SIOCSIFMTU");
 }
 
+void
+setiflladdr(val, d)
+	char *val;
+	int d;
+{
+	struct ether_addr	*ea;
+
+	ea = ether_aton(val);
+	if (ea == NULL) {
+		warn("malformed link-level address");
+		return;
+	}
+	strncpy(ifr.ifr_name, name, sizeof (ifr.ifr_name));
+	ifr.ifr_addr.sa_len = ETHER_ADDR_LEN;
+	ifr.ifr_addr.sa_family = AF_LINK;
+	bcopy(ea, ifr.ifr_addr.sa_data, ETHER_ADDR_LEN);
+	if (ioctl(s, SIOCSIFLLADDR, (caddr_t)&ifr) < 0)
+		warn("SIOCSIFLLADDR");
+
+	return;
+}
+
 const char *
 get_string(val, sep, buf, lenp)
 	const char *val, *sep;
@@ -2594,7 +2618,7 @@ usage()
 		"[ netmask mask ] ]\n"
 		"\t[ media media_type ] [ mediaopt media_option ]\n"
 		"\t[ metric n ]\n"
-		"\t[ mtu n ]\n"
+		"\t[ mtu n ] [ lladdr hwaddr ]\n"
 		"\t[ nwid network_id ] [ nwkey network_key | -nwkey ]\n"
 		"\t[ powersave | -powersave ] [ powersavesleep duration ]\n"
 		"\t[ [af] tunnel srcaddress dstaddress ] [ deletetunnel ]\n"