Merge in a stable fix from OpenBSD:

  MFC:
  Fix by dhartmei@

  change pf_route() loop detection: introduce a counter (number of times
  a packet is routed already) in the mbuf tag, allow at most four times.
  Fixes some legitimate cases broken by the previous change.

Reviewed by:	dhartmei

1 files changed, 63 insertions, 52 deletions

diff --git a/sys/contrib/pf/net/pf.c b/sys/contrib/pf/net/pf.c
index 085f5cb..5df3ba6 100644
--- a/sys/contrib/pf/net/pf.c
+++ b/sys/contrib/pf/net/pf.c
@@ -1,5 +1,5 @@
 /*	$FreeBSD$	*/
-/*	$OpenBSD: pf.c,v 1.433.2.1 2004/04/30 21:46:33 brad Exp $ */
+/*	$OpenBSD: pf.c,v 1.433.2.2 2004/07/17 03:22:34 brad Exp $ */
 
 /*
  * Copyright (c) 2001 Daniel Hartmeier
@@ -5119,12 +5119,12 @@ pf_route(struct mbuf **m, struct pf_rule *r, int dir, struct ifnet *oifp,
     struct pf_state *s)
 {
 	struct mbuf		*m0, *m1;
+	struct m_tag		*mtag;
 	struct route		 iproute;
 	struct route		*ro = NULL;	/* XXX: was uninitialized */
 	struct sockaddr_in	*dst;
 	struct ip		*ip;
 	struct ifnet		*ifp = NULL;
-	struct m_tag		*mtag;
 	struct pf_addr		 naddr;
 	struct pf_src_node	*sn = NULL;
 	int			 error = 0;
@@ -5136,22 +5136,34 @@ pf_route(struct mbuf **m, struct pf_rule *r, int dir, struct ifnet *oifp,
 	    (dir != PF_IN && dir != PF_OUT) || oifp == NULL)
 		panic("pf_route: invalid parameters");
 
-	if (r->rt == PF_DUPTO) {
-		m0 = *m;
-		mtag = m_tag_find(m0, PACKET_TAG_PF_ROUTED, NULL);
-		if (mtag == NULL) {
-			mtag = m_tag_get(PACKET_TAG_PF_ROUTED, 0, M_NOWAIT);
-			if (mtag == NULL)
-				goto bad;
-			m_tag_prepend(m0, mtag);
+	if ((mtag = m_tag_find(*m, PACKET_TAG_PF_ROUTED, NULL)) == NULL) {
+		if ((mtag = m_tag_get(PACKET_TAG_PF_ROUTED, 1, M_NOWAIT)) ==
+		    NULL) {
+			m0 = *m;
+			*m = NULL;
+			goto bad;
 		}
+		*(char *)(mtag + 1) = 1;
+		m_tag_prepend(*m, mtag);
+	} else {
+		if (*(char *)(mtag + 1) > 3) {
+			m0 = *m;
+			*m = NULL;
+			goto bad;
+		}
+		(*(char *)(mtag + 1))++;
+	}
+
+	if (r->rt == PF_DUPTO) {
 #ifdef __FreeBSD__
-		m0 = m_dup(*m, M_DONTWAIT);
+		if ((m0 = m_dup(*m, M_DONTWAIT)) == NULL)
 #else
-		m0 = m_copym2(*m, 0, M_COPYALL, M_NOWAIT);
+		if ((m0 = m_copym2(*m, 0, M_COPYALL, M_NOWAIT)) == NULL)
 #endif
-		if (m0 == NULL)
 			return;
+		if ((mtag = m_tag_copy(mtag)) == NULL)
+			goto bad;
+		m_tag_prepend(m0, mtag);
 	} else {
 		if ((r->rt == PF_REPLYTO) == (r->direction == dir))
 			return;
@@ -5198,17 +5210,9 @@ pf_route(struct mbuf **m, struct pf_rule *r, int dir, struct ifnet *oifp,
 			ifp = s->rt_kif ? s->rt_kif->pfik_ifp : NULL;
 		}
 	}
-
 	if (ifp == NULL)
 		goto bad;
 
-	if (m_tag_find(m0, PACKET_TAG_PF_ROUTED, NULL) != NULL)
-		goto bad;
-	mtag = m_tag_get(PACKET_TAG_PF_ROUTED, 0, M_NOWAIT);
-	if (mtag == NULL)
-		goto bad;
-	m_tag_prepend(m0, mtag);
-
 	if (oifp != ifp) {
 #ifdef __FreeBSD__
 		PF_UNLOCK();
@@ -5415,22 +5419,34 @@ pf_route6(struct mbuf **m, struct pf_rule *r, int dir, struct ifnet *oifp,
 	    (dir != PF_IN && dir != PF_OUT) || oifp == NULL)
 		panic("pf_route6: invalid parameters");
 
-	if (r->rt == PF_DUPTO) {
-		m0 = *m;
-		mtag = m_tag_find(m0, PACKET_TAG_PF_ROUTED, NULL);
-		if (mtag == NULL) {
-			mtag = m_tag_get(PACKET_TAG_PF_ROUTED, 0, M_NOWAIT);
-			if (mtag == NULL)
-				goto bad;
-			m_tag_prepend(m0, mtag);
+	if ((mtag = m_tag_find(*m, PACKET_TAG_PF_ROUTED, NULL)) == NULL) {
+		if ((mtag = m_tag_get(PACKET_TAG_PF_ROUTED, 1, M_NOWAIT)) ==
+		    NULL) {
+			m0 = *m;
+			*m = NULL;
+			goto bad;
 		}
+		*(char *)(mtag + 1) = 1;
+		m_tag_prepend(*m, mtag);
+	} else {
+		if (*(char *)(mtag + 1) > 3) {
+			m0 = *m;
+			*m = NULL;
+			goto bad;
+		}
+		(*(char *)(mtag + 1))++;
+	}
+
+	if (r->rt == PF_DUPTO) {
 #ifdef __FreeBSD__
-		m0 = m_dup(*m, M_DONTWAIT);
+		if ((m0 = m_dup(*m, M_DONTWAIT)) == NULL)
 #else
-		m0 = m_copym2(*m, 0, M_COPYALL, M_NOWAIT);
+		if ((m0 = m_copym2(*m, 0, M_COPYALL, M_NOWAIT)) == NULL)
 #endif
-		if (m0 == NULL)
 			return;
+		if ((mtag = m_tag_copy(mtag)) == NULL)
+			goto bad;
+		m_tag_prepend(m0, mtag);
 	} else {
 		if ((r->rt == PF_REPLYTO) == (r->direction == dir))
 			return;
@@ -5480,34 +5496,29 @@ pf_route6(struct mbuf **m, struct pf_rule *r, int dir, struct ifnet *oifp,
 			    &s->rt_addr, AF_INET6);
 		ifp = s->rt_kif ? s->rt_kif->pfik_ifp : NULL;
 	}
-
 	if (ifp == NULL)
 		goto bad;
 
 	if (oifp != ifp) {
-		mtag = m_tag_find(m0, PACKET_TAG_PF_ROUTED, NULL);
-		if (mtag == NULL) {
-			mtag = m_tag_get(PACKET_TAG_PF_ROUTED, 0, M_NOWAIT);
-			if (mtag == NULL)
-				goto bad;
-			m_tag_prepend(m0, mtag);
 #ifdef __FreeBSD__
-			PF_UNLOCK();
-			if (pf_test6(PF_OUT, ifp, &m0) != PF_PASS) {
-				PF_LOCK();
-				goto bad;
-			} else if (m0 == NULL) {
-				PF_LOCK();
-				goto done;
-			}
+		PF_UNLOCK();
+		if (pf_test6(PF_OUT, ifp, &m0) != PF_PASS) {
+			PF_LOCK();
+			goto bad;
+		} else if (m0 == NULL) {
 			PF_LOCK();
+			goto done;
+		}
+		PF_LOCK();
 #else
-			if (pf_test6(PF_OUT, ifp, &m0) != PF_PASS)
-				goto bad;
-			else if (m0 == NULL)
-				goto done;
+		if (pf_test6(PF_OUT, ifp, &m0) != PF_PASS)
+			goto bad;
+		else if (m0 == NULL)
+			goto done;
 #endif
-		}
+		if (m0->m_len < sizeof(struct ip6_hdr))
+			panic("pf_route6: m0->m_len < sizeof(struct ip6_hdr)");
+		ip6 = mtod(m0, struct ip6_hdr *);
 	}
 
 	/*