Move carp load balancing (ARP/IP) to a simpler configuration scheme.

Instead of using the same IP on multiple interfaces, carp has to be
configured with the new "carpnodes" and "balancing" options.
 # ifconfig carp0 carpnodes 1:0,2:100,3:100 balancing ip carpdev sis0 192.168.5.50

Please note, that this is a flag day for anyone using carp balancing.
You'll need to adjust your configuration accordingly.

Addititionally this diff adds IPv6 NDP balancing support.

Tested and OK mcbride@, reyk@.
Manpage help by jmc@.

3 files changed, 65 insertions, 12 deletions

diff --git a/sbin/ifconfig/ifconfig.8 b/sbin/ifconfig/ifconfig.8
index dbc0621e741..43565c49db2 100644
--- a/sbin/ifconfig/ifconfig.8
+++ b/sbin/ifconfig/ifconfig.8
@@ -1,4 +1,4 @@
-.\"	$OpenBSD: ifconfig.8,v 1.151 2007/11/09 15:07:08 jmc Exp $
+.\"	$OpenBSD: ifconfig.8,v 1.152 2008/02/05 22:57:30 mpf Exp $
 .\"	$NetBSD: ifconfig.8,v 1.11 1996/01/04 21:27:29 pk Exp $
 .\"     $FreeBSD: ifconfig.8,v 1.16 1998/02/01 07:03:29 steve Exp $
 .\"
@@ -31,7 +31,7 @@
 .\"
 .\"     @(#)ifconfig.8	8.4 (Berkeley) 6/1/94
 .\"
-.Dd $Mdocdate: November 9 2007 $
+.Dd $Mdocdate: February 5 2008 $
 .Dt IFCONFIG 8
 .Os
 .Sh NAME
@@ -445,6 +445,8 @@ and
 .Ar carp-interface
 .Op Cm advbase Ar n
 .Op Cm advskew Ar n
+.Op Cm balancing Ar mode
+.Op Cm carpnodes Ar vhid:advskew,vhid:advskew,...
 .Op Cm carpdev Ar iface
 .Op Cm pass Ar passphrase
 .Op Cm state Ar state
@@ -466,6 +468,24 @@ If the driver is a
 pseudo-device, skew the advertisement interval by
 .Ar n .
 This is an 8-bit number; the default value is 0.
+.It Cm balancing Ar mode
+If the driver is a
+.Xr carp 4
+pseudo-device, set the load balancing mode to
+.Ar mode .
+Valid modes are
+.Ar arp ,
+.Ar ip ,
+.Ar ip-stealth ,
+and
+.Ar ip-unicast .
+.It Cm carpnodes Ar vhid:advskew,vhid:advskew,...
+If the driver is a
+.Xr carp 4
+pseudo-device, create a load balancing group consisting of up to 32 nodes.
+Each node is specified as a
+.Ar vhid:advskew
+tuple in a comma separated list.
 .It Cm carpdev Ar iface
 If the driver is a
 .Xr carp 4
diff --git a/sbin/ifconfig/ifconfig.c b/sbin/ifconfig/ifconfig.c
index 6efed484d53..addce6ad612 100644
--- a/sbin/ifconfig/ifconfig.c
+++ b/sbin/ifconfig/ifconfig.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ifconfig.c,v 1.192 2007/11/27 16:21:02 chl Exp $	*/
+/*	$OpenBSD: ifconfig.c,v 1.193 2008/02/05 22:57:30 mpf Exp $	*/
 /*	$NetBSD: ifconfig.c,v 1.40 1997/10/01 02:19:43 enami Exp $	*/
 
 /*
@@ -196,7 +196,8 @@ void	setcarp_vhid(const char *, int);
 void	setcarp_state(const char *, int);
 void	setcarpdev(const char *, int);
 void	unsetcarpdev(const char *, int);
-void	setcarpnodes(const char *, int);
+void	setcarp_nodes(const char *, int);
+void	setcarp_balancing(const char *, int);
 void	setpfsync_syncdev(const char *, int);
 void	setpfsync_maxupd(const char *, int);
 void	unsetpfsync_syncdev(const char *, int);
@@ -314,7 +315,8 @@ const struct	cmd {
 	{ "vhid",	NEXTARG,	0,		setcarp_vhid },
 	{ "state",	NEXTARG,	0,		setcarp_state },
 	{ "carpdev",	NEXTARG,	0,		setcarpdev },
-	{ "carpnodes",	NEXTARG,	0,		setcarpnodes },
+	{ "carpnodes",	NEXTARG,	0,		setcarp_nodes },
+	{ "balancing",	NEXTARG,	0,		setcarp_balancing },
 	{ "-carpdev",	1,		0,		unsetcarpdev },
 	{ "syncdev",	NEXTARG,	0,		setpfsync_syncdev },
 	{ "-syncdev",	1,		0,		unsetpfsync_syncdev },
@@ -2885,11 +2887,12 @@ unsetvlandev(const char *val, int d)
 }
 
 static const char *carp_states[] = { CARP_STATES };
+static const char *carp_bal_modes[] = { CARP_BAL_MODES };
 
 void
 carp_status(void)
 {
-	const char *state;
+	const char *state, *balmode;
 	struct carpreq carpr;
 	int i;
 
@@ -2902,6 +2905,11 @@ carp_status(void)
 	if (carpr.carpr_vhids[0] == 0)
 		return;
 
+	if (carpr.carpr_balancing > CARP_BAL_MAXID)
+		balmode = "<UNKNOWN>";
+	else
+		balmode = carp_bal_modes[carpr.carpr_balancing];
+
 	for (i = 0; carpr.carpr_vhids[i]; i++) {
 		if (carpr.carpr_states[i] > CARP_MAXSTATE)
 			state = "<UNKNOWN>";
@@ -2915,10 +2923,11 @@ carp_status(void)
 		    	    carpr.carpr_advbase, carpr.carpr_advskews[0]);
 		} else {
 			if (i == 0) {
-				printf("\tcarp: carpdev %s advbase %d\n",
+				printf("\tcarp: carpdev %s advbase %d"
+				    " balancing %s\n",
 				    carpr.carpr_carpdev[0] != '\0' ?
 				    carpr.carpr_carpdev : "none",
-				    carpr.carpr_advbase);
+				    carpr.carpr_advbase, balmode);
 			}
 			printf("\t\tstate %s vhid %u advskew %u\n", state,
 			    carpr.carpr_vhids[i], carpr.carpr_advskews[i]);
@@ -3078,7 +3087,7 @@ unsetcarpdev(const char *val, int d)
 }
 
 void
-setcarpnodes(const char *val, int d)
+setcarp_nodes(const char *val, int d)
 {
 	char *str;
 	int i;
@@ -3120,6 +3129,31 @@ setcarpnodes(const char *val, int d)
 }
 
 void
+setcarp_balancing(const char *val, int d)
+{
+	int i;
+	struct carpreq carpr;
+
+	bzero((char *)&carpr, sizeof(struct carpreq));
+	ifr.ifr_data = (caddr_t)&carpr;
+
+	if (ioctl(s, SIOCGVH, (caddr_t)&ifr) == -1)
+		err(1, "SIOCGVH");
+
+	for (i = 0; i <= CARP_BAL_MAXID; i++)
+		if (!strcasecmp(val, carp_bal_modes[i]))
+			break;
+
+	if (i > CARP_BAL_MAXID)
+		errx(1, "balancing %s: unknown mode", val);
+
+	carpr.carpr_balancing = i;
+
+	if (ioctl(s, SIOCSVH, (caddr_t)&ifr) == -1)
+		err(1, "SIOCSVH");
+}
+
+void
 setpfsync_syncdev(const char *val, int d)
 {
 	struct pfsyncreq preq;
diff --git a/sbin/sysctl/sysctl.8 b/sbin/sysctl/sysctl.8
index f94db1845d9..4dbf1da49e0 100644
--- a/sbin/sysctl/sysctl.8
+++ b/sbin/sysctl/sysctl.8
@@ -1,4 +1,4 @@
-.\"	$OpenBSD: sysctl.8,v 1.142 2007/11/11 15:48:35 jmc Exp $
+.\"	$OpenBSD: sysctl.8,v 1.143 2008/02/05 22:57:31 mpf Exp $
 .\"	$NetBSD: sysctl.8,v 1.4 1995/09/30 07:12:49 thorpej Exp $
 .\"
 .\" Copyright (c) 1993
@@ -30,7 +30,7 @@
 .\"
 .\"	@(#)sysctl.8	8.2 (Berkeley) 5/9/95
 .\"
-.Dd $Mdocdate: November 11 2007 $
+.Dd $Mdocdate: February 5 2008 $
 .Dt SYSCTL 8
 .Os
 .Sh NAME
@@ -277,7 +277,6 @@ not all of the variables are relevant to all architectures.
 .It net.inet.carp.allow	integer	yes
 .It net.inet.carp.preempt	integer	yes
 .It net.inet.carp.log	integer	yes
-.It net.inet.carp.arpbalance	integer	yes
 .It net.inet6.ip6.forwarding	integer	yes
 .It net.inet6.ip6.redirect	integer	yes
 .It net.inet6.ip6.hlim	integer	yes