When checking the IPsec enable sysctls, ipsec_common_input() had

switches for protocol and address family.  Move this code to the
specific functions from where the common function is called.
As a consequence the raw ip input functions can never be called
from udp_input() anymore.  If IPsec is disabled, the functions
ah6_input(), esp6_input(), and ipcomp6_input() do not start processing
the header chain.  The raw ip input functions are called with the
mbuf and offset pointers from the protocol walking loop which is
the usual behavior.
OK mpi@ markus@

1 files changed, 43 insertions, 25 deletions

diff --git a/sys/netinet/ipsec_input.c b/sys/netinet/ipsec_input.c
index 13b33f3f947..112a5535bb0 100644
--- a/sys/netinet/ipsec_input.c
+++ b/sys/netinet/ipsec_input.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ipsec_input.c,v 1.162 2018/05/12 21:24:43 bluhm Exp $	*/
+/*	$OpenBSD: ipsec_input.c,v 1.163 2018/05/14 15:24:23 bluhm Exp $	*/
 /*
  * The authors of this code are John Ioannidis (ji@tla.org),
  * Angelos D. Keromytis (kermit@csd.uch.gr) and
@@ -175,30 +175,6 @@ ipsec_common_input(struct mbuf *m, int skip, int protoff, int af, int sproto,
 		return EINVAL;
 	}
 
-	if ((sproto == IPPROTO_ESP && !esp_enable) ||
-	    (sproto == IPPROTO_AH && !ah_enable) ||
-#if NPF > 0
-	    (m->m_pkthdr.pf.flags & PF_TAG_DIVERTED) ||
-#endif
-	    (sproto == IPPROTO_IPCOMP && !ipcomp_enable)) {
-		switch (af) {
-		case AF_INET:
-			rip_input(&m, &skip, sproto, af);
-			break;
-#ifdef INET6
-		case AF_INET6:
-			rip6_input(&m, &skip, sproto, af);
-			break;
-#endif /* INET6 */
-		default:
-			DPRINTF(("%s: unsupported protocol family %d\n",
-			    __func__, af));
-			IPSEC_ISTAT(esps_nopf, ahs_nopf, ipcomps_nopf);
-			error = EPFNOSUPPORT;
-			goto drop;
-		}
-		return 0;
-	}
 	if ((sproto == IPPROTO_IPCOMP) && (m->m_flags & M_COMP)) {
 		DPRINTF(("%s: repeated decompression\n", __func__));
 		ipcompstat_inc(ipcomps_pdrops);
@@ -790,6 +766,13 @@ ipcomp_sysctl_ipcompstat(void *oldp, size_t *oldlenp, void *newp)
 int
 ah4_input(struct mbuf **mp, int *offp, int proto, int af)
 {
+	if (
+#if NPF > 0
+	    ((*mp)->m_pkthdr.pf.flags & PF_TAG_DIVERTED) ||
+#endif
+	    !ah_enable)
+		return rip_input(mp, offp, proto, af);
+
 	ipsec_common_input(*mp, *offp, offsetof(struct ip, ip_p), AF_INET,
 	    proto, 0);
 	return IPPROTO_DONE;
@@ -810,6 +793,13 @@ ah4_ctlinput(int cmd, struct sockaddr *sa, u_int rdomain, void *v)
 int
 esp4_input(struct mbuf **mp, int *offp, int proto, int af)
 {
+	if (
+#if NPF > 0
+	    ((*mp)->m_pkthdr.pf.flags & PF_TAG_DIVERTED) ||
+#endif
+	    !esp_enable)
+		return rip_input(mp, offp, proto, af);
+
 	ipsec_common_input(*mp, *offp, offsetof(struct ip, ip_p), AF_INET,
 	    proto, 0);
 	return IPPROTO_DONE;
@@ -819,6 +809,13 @@ esp4_input(struct mbuf **mp, int *offp, int proto, int af)
 int
 ipcomp4_input(struct mbuf **mp, int *offp, int proto, int af)
 {
+	if (
+#if NPF > 0
+	    ((*mp)->m_pkthdr.pf.flags & PF_TAG_DIVERTED) ||
+#endif
+	    !ipcomp_enable)
+		return rip_input(mp, offp, proto, af);
+
 	ipsec_common_input(*mp, *offp, offsetof(struct ip, ip_p), AF_INET,
 	    proto, 0);
 	return IPPROTO_DONE;
@@ -959,6 +956,13 @@ ah6_input(struct mbuf **mp, int *offp, int proto, int af)
 	int protoff, nxt;
 	struct ip6_ext ip6e;
 
+	if (
+#if NPF > 0
+	    ((*mp)->m_pkthdr.pf.flags & PF_TAG_DIVERTED) ||
+#endif
+	    !ah_enable)
+		return rip6_input(mp, offp, proto, af);
+
 	if (*offp < sizeof(struct ip6_hdr)) {
 		DPRINTF(("%s: bad offset\n", __func__));
 		ahstat_inc(ahs_hdrops);
@@ -1009,6 +1013,13 @@ esp6_input(struct mbuf **mp, int *offp, int proto, int af)
 	int protoff, nxt;
 	struct ip6_ext ip6e;
 
+	if (
+#if NPF > 0
+	    ((*mp)->m_pkthdr.pf.flags & PF_TAG_DIVERTED) ||
+#endif
+	    !esp_enable)
+		return rip6_input(mp, offp, proto, af);
+
 	if (*offp < sizeof(struct ip6_hdr)) {
 		DPRINTF(("%s: bad offset\n", __func__));
 		espstat_inc(esps_hdrops);
@@ -1060,6 +1071,13 @@ ipcomp6_input(struct mbuf **mp, int *offp, int proto, int af)
 	int protoff, nxt;
 	struct ip6_ext ip6e;
 
+	if (
+#if NPF > 0
+	    ((*mp)->m_pkthdr.pf.flags & PF_TAG_DIVERTED) ||
+#endif
+	    !ipcomp_enable)
+		return rip6_input(mp, offp, proto, af);
+
 	if (*offp < sizeof(struct ip6_hdr)) {
 		DPRINTF(("%s: bad offset\n", __func__));
 		ipcompstat_inc(ipcomps_hdrops);