The proxy arp entries could not be added into the system over the

IFF_POINTOPOINT link types. The reason was due to the routing
entry returned from the kernel covering the remote end is of an
interface type that does not support ARP. This patch fixes this
problem by providing a hint to the kernel routing code, which
indicates the prefix route instead of the PPP host route should
be returned to the caller. Since a host route to the local end
point is also added into the routing table, and there could be
multiple such instantiations due to multiple PPP links can be
created with the same local end IP address, this patch also fixes
the loopback route installation failure problem observed prior to
this patch. The reference count of loopback route to local end would
be either incremented or decremented. The first instantiation would
create the entry and the last removal would delete the route entry.

MFC after:	5 days

8 files changed, 86 insertions, 17 deletions

diff --git a/sys/net/if_llatbl.c b/sys/net/if_llatbl.c
index 4991c81..5992f6d 100644
--- a/sys/net/if_llatbl.c
+++ b/sys/net/if_llatbl.c
@@ -274,7 +274,9 @@ lla_rt_output(struct rt_msghdr *rtm, struct rt_addrinfo *info)
 #ifdef INET
 			if (dst->sa_family == AF_INET && 
 			    ((struct sockaddr_inarp *)dst)->sin_other != 0) {
-				struct rtentry *rt = rtalloc1(dst, 0, 0);
+				struct rtentry *rt;
+				((struct sockaddr_inarp *)dst)->sin_other = 0;
+				rt = rtalloc1(dst, 0, 0);
 				if (rt == NULL || !(rt->rt_flags & RTF_HOST)) {
 					log(LOG_INFO, "%s: RTM_ADD publish "
 					    "(proxy only) is invalid\n",
diff --git a/sys/net/if_llatbl.h b/sys/net/if_llatbl.h
index f54c78a..21357eb 100644
--- a/sys/net/if_llatbl.h
+++ b/sys/net/if_llatbl.h
@@ -159,7 +159,7 @@ struct lltable {
 				    const struct sockaddr *mask);
 	struct llentry *	(*llt_lookup)(struct lltable *, u_int flags,
 				    const struct sockaddr *l3addr);
-	int			(*llt_rtcheck)(struct ifnet *,
+	int			(*llt_rtcheck)(struct ifnet *, u_int flags,
 				    const struct sockaddr *);
 	int			(*llt_dump)(struct lltable *,
 				     struct sysctl_req *);
diff --git a/sys/net/if_var.h b/sys/net/if_var.h
index 519e6aa..148d72c 100644
--- a/sys/net/if_var.h
+++ b/sys/net/if_var.h
@@ -710,6 +710,7 @@ struct ifaddr {
 	struct mtx ifa_mtx;
 };
 #define	IFA_ROUTE	RTF_UP		/* route installed */
+#define IFA_RTSELF	RTF_HOST	/* loopback route to self installed */
 
 /* for compatibility with other BSDs */
 #define	ifa_list	ifa_link
@@ -843,6 +844,7 @@ void	if_ref(struct ifnet *);
 void	if_rele(struct ifnet *);
 int	if_setlladdr(struct ifnet *, const u_char *, int);
 void	if_up(struct ifnet *);
+/*void	ifinit(void);*/ /* declared in systm.h for main() */
 int	ifioctl(struct socket *, u_long, caddr_t, struct thread *);
 int	ifpromisc(struct ifnet *, int);
 struct	ifnet *ifunit(const char *);
diff --git a/sys/net/route.c b/sys/net/route.c
index 027772b..a938c9c 100644
--- a/sys/net/route.c
+++ b/sys/net/route.c
@@ -98,8 +98,6 @@ VNET_DEFINE(struct rtstat, rtstat);
 #define	V_rttrash	VNET(rttrash)
 #define	V_rtstat	VNET(rtstat)
 
-static void rt_maskedcopy(struct sockaddr *,
-	    struct sockaddr *, struct sockaddr *);
 
 /* compare two sockaddr structures */
 #define	sa_equal(a1, a2) (bcmp((a1), (a2), (a1)->sa_len) == 0)
@@ -1322,7 +1320,7 @@ rt_setgate(struct rtentry *rt, struct sockaddr *dst, struct sockaddr *gate)
 	return (0);
 }
 
-static void
+void
 rt_maskedcopy(struct sockaddr *src, struct sockaddr *dst, struct sockaddr *netmask)
 {
 	register u_char *cp1 = (u_char *)src;
diff --git a/sys/net/route.h b/sys/net/route.h
index 9a0bc63..a8ae867 100644
--- a/sys/net/route.h
+++ b/sys/net/route.h
@@ -384,6 +384,7 @@ void	 rt_missmsg(int, struct rt_addrinfo *, int, int);
 void	 rt_newaddrmsg(int, struct ifaddr *, int, struct rtentry *);
 void	 rt_newmaddrmsg(int, struct ifmultiaddr *);
 int	 rt_setgate(struct rtentry *, struct sockaddr *, struct sockaddr *);
+void 	 rt_maskedcopy(struct sockaddr *, struct sockaddr *, struct sockaddr *);
 
 /*
  * Note the following locking behavior:
diff --git a/sys/net/rtsock.c b/sys/net/rtsock.c
index a0677ec..df4f9ae 100644
--- a/sys/net/rtsock.c
+++ b/sys/net/rtsock.c
@@ -60,6 +60,7 @@
 #include <net/vnet.h>
 
 #include <netinet/in.h>
+#include <netinet/if_ether.h>
 #ifdef INET6
 #include <netinet6/scope6_var.h>
 #endif
@@ -622,6 +623,27 @@ route_output(struct mbuf *m, struct socket *so)
 			}
 		}
 #endif
+		/*
+		 * If performing proxied L2 entry insertion, and
+		 * the actual PPP host entry is found, perform
+		 * another search to retrieve the prefix route of
+		 * the local end point of the PPP link.
+		 */
+		if ((rtm->rtm_flags & RTF_ANNOUNCE) &&
+		    (rt->rt_ifp->if_flags & IFF_POINTOPOINT)) {
+			struct sockaddr laddr;
+			rt_maskedcopy(rt->rt_ifa->ifa_addr,
+				      &laddr,
+				      rt->rt_ifa->ifa_netmask);
+			/* 
+			 * refactor rt and no lock operation necessary
+			 */
+			rt = (struct rtentry *)rnh->rnh_matchaddr(&laddr, rnh);
+			if (rt == NULL) {
+				RADIX_NODE_HEAD_RUNLOCK(rnh);
+				senderr(ESRCH);
+			}
+		} 
 		RT_LOCK(rt);
 		RT_ADDREF(rt);
 		RADIX_NODE_HEAD_RUNLOCK(rnh);
diff --git a/sys/netinet/in.c b/sys/netinet/in.c
index 09f2f44..c5317e5 100644
--- a/sys/netinet/in.c
+++ b/sys/netinet/in.c
@@ -924,9 +924,25 @@ in_ifinit(struct ifnet *ifp, struct in_ifaddr *ia, struct sockaddr_in *sin,
 	/*
 	 * add a loopback route to self
 	 */
-	if (V_useloopback && !(ifp->if_flags & IFF_LOOPBACK))
-		error = ifa_add_loopback_route((struct ifaddr *)ia, 
+	if (V_useloopback && !(ifp->if_flags & IFF_LOOPBACK)) {
+		struct route ia_ro;
+
+		bzero(&ia_ro, sizeof(ia_ro));
+		*((struct sockaddr_in *)(&ia_ro.ro_dst)) = ia->ia_addr;
+		rtalloc_ign_fib(&ia_ro, 0, 0);
+		if ((ia_ro.ro_rt != NULL) && (ia_ro.ro_rt->rt_ifp != NULL) &&
+		    (ia_ro.ro_rt->rt_ifp == V_loif)) {
+			RT_LOCK(ia_ro.ro_rt);
+			RT_ADDREF(ia_ro.ro_rt);
+			RTFREE_LOCKED(ia_ro.ro_rt);
+		} else
+			error = ifa_add_loopback_route((struct ifaddr *)ia, 
 				       (struct sockaddr *)&ia->ia_addr);
+		if (error == 0)
+			ia->ia_flags |= IFA_RTSELF;
+		if (ia_ro.ro_rt != NULL)
+			RTFREE(ia_ro.ro_rt);
+	}
 
 	return (error);
 }
@@ -1043,7 +1059,7 @@ in_scrubprefix(struct in_ifaddr *target)
 {
 	struct in_ifaddr *ia;
 	struct in_addr prefix, mask, p;
-	int error;
+	int error = 0;
 	struct sockaddr_in prefix0, mask0;
 
 	/*
@@ -1057,9 +1073,28 @@ in_scrubprefix(struct in_ifaddr *target)
 	 * deletion is unconditional.
 	 */
 	if ((target->ia_addr.sin_addr.s_addr != INADDR_ANY) &&
-	    !(target->ia_ifp->if_flags & IFF_LOOPBACK)) {
-		error = ifa_del_loopback_route((struct ifaddr *)target,
+	    !(target->ia_ifp->if_flags & IFF_LOOPBACK) &&
+	    (target->ia_flags & IFA_RTSELF)) {
+		struct route ia_ro;
+		int freeit = 0;
+
+		bzero(&ia_ro, sizeof(ia_ro));
+		*((struct sockaddr_in *)(&ia_ro.ro_dst)) = target->ia_addr;
+		rtalloc_ign_fib(&ia_ro, 0, 0);
+		if ((ia_ro.ro_rt != NULL) && (ia_ro.ro_rt->rt_ifp != NULL) &&
+		    (ia_ro.ro_rt->rt_ifp == V_loif)) {
+			RT_LOCK(ia_ro.ro_rt);
+			if (ia_ro.ro_rt->rt_refcnt <= 1)
+				freeit = 1;
+			else
+				RT_REMREF(ia_ro.ro_rt);
+			RTFREE_LOCKED(ia_ro.ro_rt);
+		}
+		if (freeit)
+			error = ifa_del_loopback_route((struct ifaddr *)target,
 				       (struct sockaddr *)&target->ia_addr);
+		if (error == 0)
+			target->ia_flags &= ~IFA_RTSELF;
 		/* remove arp cache */
 		arp_ifscrub(target->ia_ifp, IA_SIN(target)->sin_addr.s_addr);
 	}
@@ -1317,7 +1352,7 @@ in_lltable_prefix_free(struct lltable *llt,
 
 
 static int
-in_lltable_rtcheck(struct ifnet *ifp, const struct sockaddr *l3addr)
+in_lltable_rtcheck(struct ifnet *ifp, u_int flags, const struct sockaddr *l3addr)
 {
 	struct rtentry *rt;
 
@@ -1326,7 +1361,8 @@ in_lltable_rtcheck(struct ifnet *ifp, const struct sockaddr *l3addr)
 
 	/* XXX rtalloc1 should take a const param */
 	rt = rtalloc1(__DECONST(struct sockaddr *, l3addr), 0, 0);
-	if (rt == NULL || (rt->rt_flags & RTF_GATEWAY) || rt->rt_ifp != ifp) {
+	if (rt == NULL || (rt->rt_flags & RTF_GATEWAY) || 
+	    ((rt->rt_ifp != ifp) && !(flags & LLE_PUB))) {
 #ifdef DIAGNOSTIC
 		log(LOG_INFO, "IPv4 address: \"%s\" is not on the network\n",
 		    inet_ntoa(((const struct sockaddr_in *)l3addr)->sin_addr));
@@ -1378,7 +1414,7 @@ in_lltable_lookup(struct lltable *llt, u_int flags, const struct sockaddr *l3add
 		 * verify this.
 		 */
 		if (!(flags & LLE_IFADDR) &&
-		    in_lltable_rtcheck(ifp, l3addr) != 0)
+		    in_lltable_rtcheck(ifp, flags, l3addr) != 0)
 			goto done;
 
 		lle = in_lltable_new(l3addr, flags);
diff --git a/sys/netinet6/in6.c b/sys/netinet6/in6.c
index 7254c4d..c839efd 100644
--- a/sys/netinet6/in6.c
+++ b/sys/netinet6/in6.c
@@ -1200,8 +1200,12 @@ in6_purgeaddr(struct ifaddr *ifa)
 	 * The check for the current setting of "nd6_useloopback" 
 	 * is not needed.
 	 */
-	error = ifa_del_loopback_route((struct ifaddr *)ia,
-			       (struct sockaddr *)&ia->ia_addr);
+	if (ia->ia_flags & IFA_RTSELF) {
+		error = ifa_del_loopback_route((struct ifaddr *)ia,
+				       (struct sockaddr *)&ia->ia_addr);
+		if (error == 0)
+			ia->ia_flags &= ~IFA_RTSELF;
+	}
 
 	/* stop DAD processing */
 	nd6_dad_stop(ifa);
@@ -1762,6 +1766,8 @@ in6_ifinit(struct ifnet *ifp, struct in6_ifaddr *ia,
 		|| (ifp->if_flags & IFF_LOOPBACK))) {
 		error = ifa_add_loopback_route((struct ifaddr *)ia,
 				       (struct sockaddr *)&ia->ia_addr);
+		if (error == 0)
+			ia->ia_flags |= IFA_RTSELF;
 	}
 
 	/* Add ownaddr as loopback rtentry, if necessary (ex. on p2p link). */
@@ -2347,7 +2353,9 @@ in6_lltable_prefix_free(struct lltable *llt,
 }
 
 static int
-in6_lltable_rtcheck(struct ifnet *ifp, const struct sockaddr *l3addr)
+in6_lltable_rtcheck(struct ifnet *ifp, 
+		    u_int flags, 
+		    const struct sockaddr *l3addr)
 {
 	struct rtentry *rt;
 	char ip6buf[INET6_ADDRSTRLEN];
@@ -2415,7 +2423,7 @@ in6_lltable_lookup(struct lltable *llt, u_int flags,
 		 * verify this.
 		 */
 		if (!(flags & LLE_IFADDR) &&
-		    in6_lltable_rtcheck(ifp, l3addr) != 0)
+		    in6_lltable_rtcheck(ifp, flags, l3addr) != 0)
 			return NULL;
 
 		lle = in6_lltable_new(l3addr, flags);