12-bit vhid support for FreeBSD CARP

gistfile1.txt

Index: sys/netinet/ip_carp.c
===================================================================
RCS file: /home/ncvs/src/sys/netinet/ip_carp.c,v
retrieving revision 1.52.2.2.2.1
diff -u -d -r1.52.2.2.2.1 ip_carp.c
--- sys/netinet/ip_carp.c	25 Nov 2008 02:59:29 -0000	1.52.2.2.2.1
+++ sys/netinet/ip_carp.c	18 Feb 2009 11:09:32 -0000
@@ -239,7 +239,7 @@
 carp_hmac_prepare(struct carp_softc *sc)
 {
 	u_int8_t version = CARP_VERSION, type = CARP_ADVERTISEMENT;
-	u_int8_t vhid = sc->sc_vhid & 0xff;
+	u_int16_t vhid = sc->sc_vhid & 0x0fff;
 	struct ifaddr *ifa;
 	int i, found;
 #ifdef INET
@@ -909,7 +909,6 @@
 	ch.carp_advbase = advbase;
 	ch.carp_advskew = advskew;
 	ch.carp_authlen = 7;	/* XXX DEFINE */
-	ch.carp_pad1 = 0;	/* must be zero */
 	ch.carp_cksum = 0;
 
 #ifdef INET
@@ -1935,7 +1934,7 @@
 			}
 		}
 		if (carpr.carpr_vhid > 0) {
-			if (carpr.carpr_vhid > 255) {
+			if (carpr.carpr_vhid > CARP_MAX_VHID) {
 				error = EINVAL;
 				break;
 			}
@@ -1956,8 +1955,8 @@
 			IF_LLADDR(sc->sc_ifp)[1] = 0;
 			IF_LLADDR(sc->sc_ifp)[2] = 0x5e;
 			IF_LLADDR(sc->sc_ifp)[3] = 0;
-			IF_LLADDR(sc->sc_ifp)[4] = 1;
-			IF_LLADDR(sc->sc_ifp)[5] = sc->sc_vhid;
+			IF_LLADDR(sc->sc_ifp)[4] = (sc->sc_vhid & 0x0f00) >> 8;
+			IF_LLADDR(sc->sc_ifp)[5] = (sc->sc_vhid & 0x00ff);
 			error--;
 		}
 		if (carpr.carpr_advbase > 0 || carpr.carpr_advskew > 0) {
@@ -2103,10 +2102,11 @@
 			eh->ether_shost[1] = 0;
 			eh->ether_shost[2] = 0x5e;
 			eh->ether_shost[3] = 0;
-			eh->ether_shost[4] = 1;
-			eh->ether_shost[5] = sc->sc_vhid;
+			eh->ether_shost[4] = (sc->sc_vhid & 0x0f00) >> 8;
+			eh->ether_shost[5] = (sc->sc_vhid & 0x00ff);
 		}
 		break;
+#if 0 /* XXX rather disable than run untested code */
 	case IFT_FDDI: {
 			struct fddi_header *fh;
 
@@ -2130,6 +2130,7 @@
 			th->iso88025_shost[5] = 0;
 		}
 		break;
+#endif
 	default:
 		printf("%s: carp is not supported for this interface type\n",
 		    ifp->if_xname);
Index: sys/netinet/ip_carp.h
===================================================================
RCS file: /home/ncvs/src/sys/netinet/ip_carp.h,v
retrieving revision 1.3.6.1
diff -u -d -r1.3.6.1 ip_carp.h
--- sys/netinet/ip_carp.h	25 Nov 2008 02:59:29 -0000	1.3.6.1
+++ sys/netinet/ip_carp.h	18 Feb 2009 11:12:17 -0000
@@ -36,9 +36,9 @@
  *     0                   1                   2                   3
  *     0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
  *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- *    |Version| Type  | VirtualHostID |    AdvSkew    |    Auth Len   |
+ *    |Version| Type  |     VirtualHostID     | Rsrvd |    AdvSkew    |
  *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- *    |   Reserved    |     AdvBase   |          Checksum             |
+ *    |   Auth Len    |     AdvBase   |          Checksum             |
  *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  *    |                         Counter (1)                           |
  *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
@@ -66,10 +66,9 @@
 	u_int8_t	carp_version:4,
 			carp_type:4;
 #endif
-	u_int8_t	carp_vhid;	/* virtual host id */
+	u_int16_t	carp_vhid;	/* virtual host id */
 	u_int8_t	carp_advskew;	/* advertisement skew */
 	u_int8_t	carp_authlen;   /* size of counter+md, 32bit chunks */
-	u_int8_t	carp_pad1;	/* reserved */
 	u_int8_t	carp_advbase;	/* advertisement interval */
 	u_int16_t	carp_cksum;
 	u_int32_t	carp_counter[2];
@@ -83,7 +82,7 @@
 #define	CARP_DFLTTL		255
 
 /* carp_version */
-#define	CARP_VERSION		2
+#define	CARP_VERSION		3
 
 /* carp_type */
 #define	CARP_ADVERTISEMENT	0x01
@@ -93,6 +92,8 @@
 /* carp_advbase */
 #define	CARP_DFLTINTV		1
 
+#define	CARP_MAX_VHID		4094
+
 /*
  * Statistics.
  */