Convert ip{,6}_output() (cached) route entry checks to rtisvalid(9).

This introduces a behavior change as we now reject !RTF_UP routes to
output packets.  This stricter check exposed a bug in the setup of
new routes and was the reason for the previous revert.  This should
be now fixed by r1.229 of sys/net/route.c .

ok bluhm@

1 files changed, 17 insertions, 11 deletions

diff --git a/sys/netinet/ip_output.c b/sys/netinet/ip_output.c
index 986933deca4..1436be3f2e5 100644
--- a/sys/netinet/ip_output.c
+++ b/sys/netinet/ip_output.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ip_output.c,v 1.289 2015/09/02 08:28:06 mpi Exp $	*/
+/*	$OpenBSD: ip_output.c,v 1.290 2015/09/03 09:59:59 mpi Exp $	*/
 /*	$NetBSD: ip_output.c,v 1.28 1996/02/13 23:43:07 christos Exp $	*/
 
 /*
@@ -168,12 +168,13 @@ ip_output(struct mbuf *m0, struct mbuf *opt, struct route *ro, int flags,
 		dst = satosin(&ro->ro_dst);
 
 		/*
-		 * If there is a cached route, check that it is to the same
-		 * destination and is still up.  If not, free it and try again.
+		 * If there is a cached route, check that it is to the
+		 * same destination and is still valid.  If not, free
+		 * it and try again.
 		 */
-		if (ro->ro_rt && ((ro->ro_rt->rt_flags & RTF_UP) == 0 ||
+		if (!rtisvalid(ro->ro_rt) ||
 		    dst->sin_addr.s_addr != ip->ip_dst.s_addr ||
-		    ro->ro_tableid != m->m_pkthdr.ph_rtableid)) {
+		    ro->ro_tableid != m->m_pkthdr.ph_rtableid) {
 			rtfree(ro->ro_rt);
 			ro->ro_rt = NULL;
 		}
@@ -195,7 +196,9 @@ ip_output(struct mbuf *m0, struct mbuf *opt, struct route *ro, int flags,
 				ro->ro_rt = rtalloc_mpath(&ro->ro_dst,
 				    NULL, ro->ro_tableid);
 
-			if (ro->ro_rt == NULL) {
+			if (!rtisvalid(ro->ro_rt)) {
+				rtfree(ro->ro_rt);
+				ro->ro_rt = NULL;
 				ipstat.ips_noroute++;
 				error = EHOSTUNREACH;
 				goto bad;
@@ -296,12 +299,13 @@ reroute:
 		dst = satosin(&ro->ro_dst);
 
 		/*
-		 * If there is a cached route, check that it is to the same
-		 * destination and is still up.  If not, free it and try again.
+		 * If there is a cached route, check that it is to the
+		 * same destination and is still valid.  If not, free
+		 * it and try again.
 		 */
-		if (ro->ro_rt && ((ro->ro_rt->rt_flags & RTF_UP) == 0 ||
+		if (!rtisvalid(ro->ro_rt) ||
 		    dst->sin_addr.s_addr != ip->ip_dst.s_addr ||
-		    ro->ro_tableid != m->m_pkthdr.ph_rtableid)) {
+		    ro->ro_tableid != m->m_pkthdr.ph_rtableid) {
 			rtfree(ro->ro_rt);
 			ro->ro_rt = NULL;
 		}
@@ -323,7 +327,9 @@ reroute:
 				ro->ro_rt = rtalloc_mpath(&ro->ro_dst,
 				    &ip->ip_src.s_addr, ro->ro_tableid);
 
-			if (ro->ro_rt == NULL) {
+			if (!rtisvalid(ro->ro_rt)) {
+				rtfree(ro->ro_rt);
+				ro->ro_rt = NULL;
 				ipstat.ips_noroute++;
 				error = EHOSTUNREACH;
 				goto bad;