]> git.saurik.com Git - apple/xnu.git/blobdiff - bsd/netinet6/ip6_forward.c
xnu-1699.22.73.tar.gz
[apple/xnu.git] / bsd / netinet6 / ip6_forward.c
index 202d8ccb1a9d90d175c59a3e6c91fb2a3b073022..f2d6e3bd638a73cc4a84719abb138b11acaa4813 100644 (file)
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2008 Apple Inc. All rights reserved.
+ * Copyright (c) 2009-2010 Apple Inc. All rights reserved.
  *
  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
  * 
@@ -84,6 +84,7 @@
 #include <netinet6/ip6_var.h>
 #include <netinet/icmp6.h>
 #include <netinet6/nd6.h>
+#include <netinet6/scope6_var.h>
 
 #include <netinet/in_pcb.h>
 
@@ -95,7 +96,6 @@
 #include <netkey/key.h>
 extern int ipsec_bypass;
 #endif /* IPSEC */
-extern lck_mtx_t *ip6_mutex;
 
 #include <netinet6/ip6_fw.h>
 
@@ -120,7 +120,7 @@ extern lck_mtx_t *ip6_mutex;
 
 void
 ip6_forward(struct mbuf *m, struct route_in6 *ip6forward_rt,
-    int srcrt, int locked)
+    int srcrt)
 {
        struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
        struct sockaddr_in6 *dst;
@@ -128,14 +128,24 @@ ip6_forward(struct mbuf *m, struct route_in6 *ip6forward_rt,
        int error, type = 0, code = 0;
        struct mbuf *mcopy = NULL;
        struct ifnet *ifp, *origifp;    /* maybe unnecessary */
+       u_int32_t inzone, outzone;
+       struct in6_addr src_in6, dst_in6;
 #if IPSEC
        struct secpolicy *sp = NULL;
 #endif
        struct timeval timenow;
        int     tunneledv4 = 0;
+       unsigned int ifscope = IFSCOPE_NONE;
+#if PF
+       struct pf_mtag *pf_mtag;
+#endif /* PF */
 
        getmicrotime(&timenow);
-
+#if PF
+       pf_mtag = pf_find_mtag(m);
+       if (pf_mtag != NULL && pf_mtag->rtableid != IFSCOPE_NONE)
+               ifscope = pf_mtag->rtableid;
+#endif /* PF */
 
 #if IPSEC
        /*
@@ -181,12 +191,8 @@ ip6_forward(struct mbuf *m, struct route_in6 *ip6forward_rt,
 
        if (ip6->ip6_hlim <= IPV6_HLIMDEC) {
                /* XXX in6_ifstat_inc(rt->rt_ifp, ifs6_in_discard) */
-               if (locked)
-                       lck_mtx_unlock(ip6_mutex);
                icmp6_error(m, ICMP6_TIME_EXCEEDED,
                                ICMP6_TIME_EXCEED_TRANSIT, 0);
-               if (locked)
-                       lck_mtx_lock(ip6_mutex);
                return;
        }
        ip6->ip6_hlim -= IPV6_HLIMDEC;
@@ -293,11 +299,7 @@ ip6_forward(struct mbuf *m, struct route_in6 *ip6forward_rt,
        state.ro = NULL;        /* update at ipsec6_output_tunnel() */
        state.dst = NULL;       /* update at ipsec6_output_tunnel() */
 
-       if (locked)
-               lck_mtx_unlock(ip6_mutex);
        error = ipsec6_output_tunnel(&state, sp, 0, &tunneledv4);
-       if (locked)
-               lck_mtx_lock(ip6_mutex);
        key_freesp(sp, KEY_SADB_UNLOCKED);
        if (tunneledv4)
                return;  /* packet is gone - sent over IPv4 */
@@ -334,15 +336,6 @@ ip6_forward(struct mbuf *m, struct route_in6 *ip6forward_rt,
     skip_ipsec:
 #endif /* IPSEC */
 
-       /*
-        * If "locked", ip6forward_rt points to the globally defined
-        * struct route cache which requires ip6_mutex, e.g. when this
-        * is called from ip6_input().  Else the caller is responsible
-        * for the struct route and its serialization (if needed), e.g.
-        * when this is called from ip6_rthdr0().
-        */
-       if (locked)
-               lck_mtx_assert(ip6_mutex, LCK_MTX_ASSERT_OWNED);
        dst = (struct sockaddr_in6 *)&ip6forward_rt->ro_dst;
        if ((rt = ip6forward_rt->ro_rt) != NULL) {
                RT_LOCK(rt);
@@ -364,8 +357,8 @@ ip6_forward(struct mbuf *m, struct route_in6 *ip6forward_rt,
                                ip6forward_rt->ro_rt = NULL;
                        }
                        /* this probably fails but give it a try again */
-                       rtalloc_ign((struct route *)ip6forward_rt,
-                           RTF_PRCLONING);
+                       rtalloc_scoped_ign((struct route *)ip6forward_rt,
+                           RTF_PRCLONING, ifscope);
                        if ((rt = ip6forward_rt->ro_rt) != NULL) {
                                RT_LOCK(rt);
                                /* Take an extra ref for ourselves */
@@ -376,14 +369,9 @@ ip6_forward(struct mbuf *m, struct route_in6 *ip6forward_rt,
                if (rt == NULL) {
                        ip6stat.ip6s_noroute++;
                        in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_noroute);
-                       if (mcopy) {
-                               if (locked)
-                                       lck_mtx_unlock(ip6_mutex);
+                       if (mcopy)
                                icmp6_error(mcopy, ICMP6_DST_UNREACH,
                                            ICMP6_DST_UNREACH_NOROUTE, 0);
-                               if (locked)
-                                       lck_mtx_lock(ip6_mutex);
-                       }
                        m_freem(m);
                        return;
                }
@@ -403,18 +391,14 @@ ip6_forward(struct mbuf *m, struct route_in6 *ip6forward_rt,
                dst->sin6_family = AF_INET6;
                dst->sin6_addr = ip6->ip6_dst;
 
-               rtalloc_ign((struct route *)ip6forward_rt, RTF_PRCLONING);
+               rtalloc_scoped_ign((struct route *)ip6forward_rt,
+                   RTF_PRCLONING, ifscope);
                if ((rt = ip6forward_rt->ro_rt) == NULL) {
                        ip6stat.ip6s_noroute++;
                        in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_noroute);
-                       if (mcopy) {
-                               if (locked)
-                                       lck_mtx_unlock(ip6_mutex);
+                       if (mcopy)
                                icmp6_error(mcopy, ICMP6_DST_UNREACH,
                                    ICMP6_DST_UNREACH_NOROUTE, 0);
-                               if (locked)
-                                       lck_mtx_lock(ip6_mutex);
-                       }
                        m_freem(m);
                        return;
                }
@@ -424,14 +408,29 @@ ip6_forward(struct mbuf *m, struct route_in6 *ip6forward_rt,
        }
 
        /*
-        * Scope check: if a packet can't be delivered to its destination
-        * for the reason that the destination is beyond the scope of the
-        * source address, discard the packet and return an icmp6 destination
-        * unreachable error with Code 2 (beyond scope of source address).
-        * [draft-ietf-ipngwg-icmp-v3-02.txt, Section 3.1]
+        * Source scope check: if a packet can't be delivered to its
+        * destination for the reason that the destination is beyond the scope
+        * of the source address, discard the packet and return an icmp6
+        * destination unreachable error with Code 2 (beyond scope of source
+        * address).  We use a local copy of ip6_src, since in6_setscope()
+        * will possibly modify its first argument.
+        * [draft-ietf-ipngwg-icmp-v3-04.txt, Section 3.1]
         */
-       if (in6_addr2scopeid(m->m_pkthdr.rcvif, &ip6->ip6_src) !=
-           in6_addr2scopeid(rt->rt_ifp, &ip6->ip6_src)) {
+       src_in6 = ip6->ip6_src;
+       if (in6_setscope(&src_in6, rt->rt_ifp, &outzone)) {
+               /* XXX: this should not happen */
+               ip6stat.ip6s_cantforward++;
+               ip6stat.ip6s_badscope++;
+               m_freem(m);
+               return;
+       }
+       if (in6_setscope(&src_in6, m->m_pkthdr.rcvif, &inzone)) {
+               ip6stat.ip6s_cantforward++;
+               ip6stat.ip6s_badscope++;
+               m_freem(m);
+               return;
+       }
+       if (inzone != outzone) {
                ip6stat.ip6s_cantforward++;
                ip6stat.ip6s_badscope++;
                in6_ifstat_inc(rt->rt_ifp, ifs6_in_discard);
@@ -450,17 +449,30 @@ ip6_forward(struct mbuf *m, struct route_in6 *ip6forward_rt,
                RT_REMREF_LOCKED(rt);
                RT_UNLOCK(rt);
                if (mcopy) {
-                       if (locked)
-                               lck_mtx_unlock(ip6_mutex);
                        icmp6_error(mcopy, ICMP6_DST_UNREACH,
                                    ICMP6_DST_UNREACH_BEYONDSCOPE, 0);
-                       if (locked)
-                               lck_mtx_lock(ip6_mutex);
                }
                m_freem(m);
                return;
        }
 
+       /*
+        * Destination scope check: if a packet is going to break the scope
+        * zone of packet's destination address, discard it.  This case should
+        * usually be prevented by appropriately-configured routing table, but
+        * we need an explicit check because we may mistakenly forward the
+        * packet to a different zone by (e.g.) a default route.
+        */
+       dst_in6 = ip6->ip6_dst;
+       if (in6_setscope(&dst_in6, m->m_pkthdr.rcvif, &inzone) != 0 ||
+           in6_setscope(&dst_in6, rt->rt_ifp, &outzone) != 0 ||
+           inzone != outzone) {
+               ip6stat.ip6s_cantforward++;
+               ip6stat.ip6s_badscope++;
+               m_freem(m);
+               return;
+       }
+
        if (m->m_pkthdr.len > rt->rt_ifp->if_mtu) {
                in6_ifstat_inc(rt->rt_ifp, ifs6_in_toobig);
                if (mcopy) {
@@ -475,7 +487,7 @@ ip6_forward(struct mbuf *m, struct route_in6 *ip6forward_rt,
 #if IPSEC
                        /*
                         * When we do IPsec tunnel ingress, we need to play
-                        * with if_mtu value (decrement IPsec header size
+                        * with the link value (decrement IPsec header size
                         * from mtu value).  The code is much simpler than v4
                         * case, as we have the outgoing interface for
                         * encapsulated packet as "rt->rt_ifp".
@@ -499,11 +511,7 @@ ip6_forward(struct mbuf *m, struct route_in6 *ip6forward_rt,
                        /* Release extra ref */
                        RT_REMREF_LOCKED(rt);
                        RT_UNLOCK(rt);
-                       if (locked)
-                               lck_mtx_unlock(ip6_mutex);
                        icmp6_error(mcopy, ICMP6_PACKET_TOO_BIG, 0, mtu);
-                       if (locked)
-                               lck_mtx_lock(ip6_mutex);
                } else {
                        /* Release extra ref */
                        RT_REMREF_LOCKED(rt);
@@ -525,7 +533,7 @@ ip6_forward(struct mbuf *m, struct route_in6 *ip6forward_rt,
         * Also, don't send redirect if forwarding using a route
         * modified by a redirect.
         */
-       if (rt->rt_ifp == m->m_pkthdr.rcvif && !srcrt &&
+       if (ip6_sendredirects && rt->rt_ifp == m->m_pkthdr.rcvif && !srcrt &&
            (rt->rt_flags & (RTF_DYNAMIC|RTF_MODIFIED)) == 0) {
                if ((rt->rt_ifp->if_flags & IFF_POINTOPOINT) != 0) {
                        /*
@@ -540,12 +548,8 @@ ip6_forward(struct mbuf *m, struct route_in6 *ip6forward_rt,
                         */
                        RT_REMREF_LOCKED(rt);   /* Release extra ref */
                        RT_UNLOCK(rt);
-                       if (locked)
-                               lck_mtx_unlock(ip6_mutex);
                        icmp6_error(mcopy, ICMP6_DST_UNREACH,
                                    ICMP6_DST_UNREACH_ADDR, 0);
-                       if (locked)
-                               lck_mtx_lock(ip6_mutex);
                        m_freem(m);
                        return;
                }
@@ -611,29 +615,21 @@ ip6_forward(struct mbuf *m, struct route_in6 *ip6forward_rt,
        }
        else
                origifp = rt->rt_ifp;
-#ifndef SCOPEDROUTING
        /*
         * clear embedded scope identifiers if necessary.
         * in6_clearscope will touch the addresses only when necessary.
         */
        in6_clearscope(&ip6->ip6_src);
        in6_clearscope(&ip6->ip6_dst);
-#endif
 
        ifp = rt->rt_ifp;
        /* Drop the lock but retain the extra ref */
        RT_UNLOCK(rt);
 
 #if PF
-       if (locked)
-               lck_mtx_unlock(ip6_mutex);
-
        /* Invoke outbound packet filter */
        error = pf_af_hook(ifp, NULL, &m, AF_INET6, FALSE);
 
-       if (locked)
-               lck_mtx_lock(ip6_mutex);
-
        if (error) {
                if (m != NULL) {
                        panic("%s: unexpected packet %p\n", __func__, m);
@@ -645,7 +641,7 @@ ip6_forward(struct mbuf *m, struct route_in6 *ip6forward_rt,
        ip6 = mtod(m, struct ip6_hdr *);
 #endif /* PF */
 
-       error = nd6_output(ifp, origifp, m, dst, rt, locked);
+       error = nd6_output(ifp, origifp, m, dst, rt);
        if (error) {
                in6_ifstat_inc(ifp, ifs6_out_discard);
                ip6stat.ip6s_cantforward++;
@@ -697,11 +693,7 @@ senderr:
                code = ICMP6_DST_UNREACH_ADDR;
                break;
        }
-       if (locked)
-               lck_mtx_unlock(ip6_mutex);
        icmp6_error(mcopy, type, code, 0);
-       if (locked)
-               lck_mtx_lock(ip6_mutex);
        /* Release extra ref */
        RT_REMREF(rt);
        return;