Implement routing priorities. Every route inserted has a priority assigned

and the one route with the lowest number wins. This will be used by the
routing daemons to resolve the synchronisations issue in case of conflicts.
The nasty bits of this are in the multipath code. If no priority is specified
the kernel will choose an appropriate priority.

Looked at by a few people at n2k8 code is much older

1 files changed, 26 insertions, 5 deletions

diff --git a/sys/net/rtsock.c b/sys/net/rtsock.c
index aadd17ff1f2..72d8b07446f 100644
--- a/sys/net/rtsock.c
+++ b/sys/net/rtsock.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: rtsock.c,v 1.69 2008/04/23 10:55:14 norby Exp $	*/
+/*	$OpenBSD: rtsock.c,v 1.70 2008/05/07 05:14:21 claudio Exp $	*/
 /*	$NetBSD: rtsock.c,v 1.18 1996/03/29 00:32:10 cgd Exp $	*/
 
 /*
@@ -186,6 +186,7 @@ route_output(struct mbuf *m, ...)
 	const char		*label;
 	va_list			 ap;
 	u_int			 tableid;
+	u_int8_t		 prio;
 
 	va_start(ap, m);
 	so = va_arg(ap, struct socket *);
@@ -262,6 +263,20 @@ route_output(struct mbuf *m, ...)
 		}
 	}
 
+	if (rtm->rtm_priority != 0) {
+		if (rtm->rtm_priority > RTP_MAX) {
+			dst = 0;
+			error = EINVAL;
+			goto flush;
+		}
+		prio = rtm->rtm_priority;
+	} else if (rtm->rtm_type == RTM_DELETE)
+		prio = RTP_ANY;
+	else if (rtm->rtm_flags & RTF_STATIC)
+		prio = RTP_STATIC;
+	else
+		prio = RTP_DEFAULT;
+
 	bzero(&info, sizeof(info));
 	info.rti_addrs = rtm->rtm_addrs;
 	rt_xaddrs(rtm->rtm_hdrlen + (caddr_t)rtm, len + (caddr_t)rtm, &info);
@@ -300,7 +315,8 @@ route_output(struct mbuf *m, ...)
 			error = EINVAL;
 			goto flush;
 		}
-		error = rtrequest1(rtm->rtm_type, &info, &saved_nrt, tableid);
+		error = rtrequest1(rtm->rtm_type, &info, prio, &saved_nrt,
+		    tableid);
 		if (error == 0 && saved_nrt) {
 			rt_setmetrics(rtm->rtm_inits, &rtm->rtm_rmx,
 			    &saved_nrt->rt_rmx);
@@ -310,7 +326,8 @@ route_output(struct mbuf *m, ...)
 		}
 		break;
 	case RTM_DELETE:
-		error = rtrequest1(rtm->rtm_type, &info, &saved_nrt, tableid);
+		error = rtrequest1(rtm->rtm_type, &info, prio, &saved_nrt,
+		    tableid);
 		if (error == 0) {
 			(rt = saved_nrt)->rt_refcnt++;
 			goto report;
@@ -339,8 +356,9 @@ route_output(struct mbuf *m, ...)
 		 * (no need to call rt_mpath_matchgate if gate == NULL)
 		 */
 		if (rn_mpath_capable(rnh) &&
-		    (rtm->rtm_type != RTM_GET || gate)) {
-			rt = rt_mpath_matchgate(rt, gate);
+		    (rtm->rtm_type != RTM_GET || gate ||
+		    rtm->rtm_priority != 0)) {
+			rt = rt_mpath_matchgate(rt, gate, prio);
 			rn = (struct radix_node *)rt;
 			if (!rt) {
 				error = ESRCH;
@@ -412,6 +430,7 @@ report:
 			    NULL);
 			rtm->rtm_flags = rt->rt_flags;
 			rtm->rtm_use = 0;
+			rtm->rtm_priority = rt->rt_priority;
 			rt_getmetrics(&rt->rt_rmx, &rtm->rtm_rmx);
 			rtm->rtm_addrs = info.rti_addrs;
 			break;
@@ -535,6 +554,7 @@ rt_setmetrics(u_long which, struct rt_metrics *in, struct rt_kmetrics *out)
 		out->rmx_mtu = in->rmx_mtu;
 	if (which & RTV_EXPIRE)
 		out->rmx_expire = in->rmx_expire;
+	/* RTV_PRIORITY handled befor */
 }
 
 void
@@ -916,6 +936,7 @@ sysctl_dumpentry(struct radix_node *rn, void *v)
 		struct rt_msghdr *rtm = (struct rt_msghdr *)w->w_tmem;
 
 		rtm->rtm_flags = rt->rt_flags;
+		rtm->rtm_priority = rt->rt_priority;
 		rt_getmetrics(&rt->rt_rmx, &rtm->rtm_rmx);
 		rtm->rtm_rmx.rmx_refcnt = rt->rt_refcnt;
 		rtm->rtm_index = rt->rt_ifp->if_index;