X-Git-Url: https://git.saurik.com/apple/xnu.git/blobdiff_plain/8ad349bb6ed4a0be06e34c92be0d98b92e078db4..d9a64523371fa019c4575bb400cbbc3a50ac9903:/bsd/netinet6/in6_pcb.c

diff --git a/bsd/netinet6/in6_pcb.c b/bsd/netinet6/in6_pcb.c
index 2c04734c6..db72c5c35 100644
--- a/bsd/netinet6/in6_pcb.c
+++ b/bsd/netinet6/in6_pcb.c
@@ -1,31 +1,29 @@
 /*
- * Copyright (c) 2003-2004 Apple Computer, Inc. All rights reserved.
+ * Copyright (c) 2003-2017 Apple Inc. All rights reserved.
  *
- * @APPLE_LICENSE_OSREFERENCE_HEADER_START@
- * 
- * This file contains Original Code and/or Modifications of Original Code 
- * as defined in and that are subject to the Apple Public Source License 
- * Version 2.0 (the 'License'). You may not use this file except in 
- * compliance with the License.  The rights granted to you under the 
- * License may not be used to create, or enable the creation or 
- * redistribution of, unlawful or unlicensed copies of an Apple operating 
- * system, or to circumvent, violate, or enable the circumvention or 
- * violation of, any terms of an Apple operating system software license 
- * agreement.
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
  *
- * Please obtain a copy of the License at 
- * http://www.opensource.apple.com/apsl/ and read it before using this 
- * file.
+ * This file contains Original Code and/or Modifications of Original Code
+ * as defined in and that are subject to the Apple Public Source License
+ * Version 2.0 (the 'License'). You may not use this file except in
+ * compliance with the License. The rights granted to you under the License
+ * may not be used to create, or enable the creation or redistribution of,
+ * unlawful or unlicensed copies of an Apple operating system, or to
+ * circumvent, violate, or enable the circumvention or violation of, any
+ * terms of an Apple operating system software license agreement.
  *
- * The Original Code and all software distributed under the License are 
- * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER 
- * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, 
- * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, 
- * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. 
- * Please see the License for the specific language governing rights and 
+ * Please obtain a copy of the License at
+ * http://www.opensource.apple.com/apsl/ and read it before using this file.
+ *
+ * The Original Code and all software distributed under the License are
+ * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
+ * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
+ * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
+ * Please see the License for the specific language governing rights and
  * limitations under the License.
  *
- * @APPLE_LICENSE_OSREFERENCE_HEADER_END@
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  */
 /*
  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
@@ -104,10 +102,13 @@
 #include <sys/errno.h>
 #include <sys/time.h>
 #include <sys/proc.h>
+#include <sys/kauth.h>
+#include <sys/priv.h>
 
 #include <net/if.h>
 #include <net/if_types.h>
 #include <net/route.h>
+#include <net/ntstat.h>
 
 #include <netinet/in.h>
 #include <netinet/in_var.h>
@@ -119,15 +120,11 @@
 #include <netinet/in_pcb.h>
 #include <netinet6/in6_pcb.h>
 #include <net/if_types.h>
+#include <net/if_var.h>
 
 #include <kern/kern_types.h>
 #include <kern/zalloc.h>
 
-#include "faith.h"
-#if defined(NFAITH) && NFAITH > 0
-#include <net/if_faith.h>
-#endif
-
 #if IPSEC
 #include <netinet6/ipsec.h>
 #if INET6
@@ -138,58 +135,114 @@
 #include <netinet6/ah6.h>
 #endif
 #include <netkey/key.h>
-extern lck_mtx_t *sadb_mutex;
 #endif /* IPSEC */
 
-struct	in6_addr zeroin6_addr;
+#if NECP
+#include <net/necp.h>
+#endif /* NECP */
+
+/*
+ * in6_pcblookup_local_and_cleanup does everything
+ * in6_pcblookup_local does but it checks for a socket
+ * that's going away. Since we know that the lock is
+ * held read+write when this function is called, we
+ * can safely dispose of this socket like the slow
+ * timer would usually do and return NULL. This is
+ * great for bind.
+ */
+static struct inpcb *
+in6_pcblookup_local_and_cleanup(struct inpcbinfo *pcbinfo,
+    struct in6_addr *laddr, u_int lport_arg, int wild_okay)
+{
+	struct inpcb *inp;
+
+	/* Perform normal lookup */
+	inp = in6_pcblookup_local(pcbinfo, laddr, lport_arg, wild_okay);
+
+	/* Check if we found a match but it's waiting to be disposed */
+	if (inp != NULL && inp->inp_wantcnt == WNT_STOPUSING) {
+		struct socket *so = inp->inp_socket;
+
+		socket_lock(so, 0);
 
+		if (so->so_usecount == 0) {
+			if (inp->inp_state != INPCB_STATE_DEAD)
+				in6_pcbdetach(inp);
+			in_pcbdispose(inp);	/* will unlock & destroy */
+			inp = NULL;
+		} else {
+			socket_unlock(so, 0);
+		}
+	}
+
+	return (inp);
+}
+
+/*
+ * Bind an INPCB to an address and/or port.  This routine should not alter
+ * the caller-supplied local address "nam".
+ */
 int
-in6_pcbbind(
-	struct inpcb *inp,
-	struct sockaddr *nam,
-	struct proc *p)
+in6_pcbbind(struct inpcb *inp, struct sockaddr *nam, struct proc *p)
 {
 	struct socket *so = inp->inp_socket;
-	struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)NULL;
 	struct inpcbinfo *pcbinfo = inp->inp_pcbinfo;
 	u_short	lport = 0;
 	int wild = 0, reuseport = (so->so_options & SO_REUSEPORT);
+	struct ifnet *outif = NULL;
+	struct sockaddr_in6 sin6;
+#if !CONFIG_EMBEDDED
+	int error;
+	kauth_cred_t cred;
+#endif /* !CONFIG_EMBEDDED */
 
 	if (!in6_ifaddrs) /* XXX broken! */
 		return (EADDRNOTAVAIL);
-	if (inp->inp_lport || !IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr))
-		return(EINVAL);
-	if ((so->so_options & (SO_REUSEADDR|SO_REUSEPORT)) == 0)
+	if (!(so->so_options & (SO_REUSEADDR|SO_REUSEPORT)))
 		wild = 1;
+
 	socket_unlock(so, 0); /* keep reference */
-	lck_rw_lock_exclusive(pcbinfo->mtx);
-	if (nam) {
-		sin6 = (struct sockaddr_in6 *)nam;
-		if (nam->sa_len != sizeof(*sin6)) {
-			lck_rw_done(pcbinfo->mtx);
+	lck_rw_lock_exclusive(pcbinfo->ipi_lock);
+	if (inp->inp_lport || !IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr)) {
+		/* another thread completed the bind */
+		lck_rw_done(pcbinfo->ipi_lock);
+		socket_lock(so, 0);
+		return (EINVAL);
+	}
+
+	bzero(&sin6, sizeof (sin6));
+	if (nam != NULL) {
+		if (nam->sa_len != sizeof (struct sockaddr_in6)) {
+			lck_rw_done(pcbinfo->ipi_lock);
 			socket_lock(so, 0);
-			return(EINVAL);
+			return (EINVAL);
 		}
 		/*
 		 * family check.
 		 */
 		if (nam->sa_family != AF_INET6) {
-			lck_rw_done(pcbinfo->mtx);
+			lck_rw_done(pcbinfo->ipi_lock);
 			socket_lock(so, 0);
-			return(EAFNOSUPPORT);
+			return (EAFNOSUPPORT);
 		}
+		lport = SIN6(nam)->sin6_port;
+
+		*(&sin6) = *SIN6(nam);
 
 		/* KAME hack: embed scopeid */
-		if (in6_embedscope(&sin6->sin6_addr, sin6, inp, NULL) != 0) {
-			lck_rw_done(pcbinfo->mtx);
+		if (in6_embedscope(&sin6.sin6_addr, &sin6, inp, NULL,
+		    NULL) != 0) {
+			lck_rw_done(pcbinfo->ipi_lock);
 			socket_lock(so, 0);
-			return EINVAL;
+			return (EINVAL);
 		}
-		/* this must be cleared for ifa_ifwithaddr() */
-		sin6->sin6_scope_id = 0;
 
-		lport = sin6->sin6_port;
-		if (IN6_IS_ADDR_MULTICAST(&sin6->sin6_addr)) {
+		/* Sanitize local copy for address searches */
+                sin6.sin6_flowinfo = 0;
+                sin6.sin6_scope_id = 0;
+		sin6.sin6_port = 0;
+
+		if (IN6_IS_ADDR_MULTICAST(&sin6.sin6_addr)) {
 			/*
 			 * Treat SO_REUSEADDR as SO_REUSEPORT for multicast;
 			 * allow compepte duplication of binding if
@@ -199,202 +252,268 @@ in6_pcbbind(
 			 */
 			if (so->so_options & SO_REUSEADDR)
 				reuseport = SO_REUSEADDR|SO_REUSEPORT;
-		} else if (!IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr)) {
-			struct ifaddr *ia = NULL;
+		} else if (!IN6_IS_ADDR_UNSPECIFIED(&sin6.sin6_addr)) {
+			struct ifaddr *ifa;
 
-			sin6->sin6_port = 0;		/* yech... */
-			if ((ia = ifa_ifwithaddr((struct sockaddr *)sin6)) == 0) {
-				lck_rw_done(pcbinfo->mtx);
+			ifa = ifa_ifwithaddr(SA(&sin6));
+			if (ifa == NULL) {
+				lck_rw_done(pcbinfo->ipi_lock);
 				socket_lock(so, 0);
-				return(EADDRNOTAVAIL);
-			}
-
-			/*
-			 * XXX: bind to an anycast address might accidentally
-			 * cause sending a packet with anycast source address.
-			 * We should allow to bind to a deprecated address, since
-			 * the application dare to use it.
-			 */
-			if (ia &&
-			    ((struct in6_ifaddr *)ia)->ia6_flags &
-			    (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY|IN6_IFF_DETACHED)) {
-			    	ifafree(ia);
-				lck_rw_done(pcbinfo->mtx);
-				socket_lock(so, 0);
-				return(EADDRNOTAVAIL);
+				return (EADDRNOTAVAIL);
+			} else {
+				/*
+				 * XXX: bind to an anycast address might
+				 * accidentally cause sending a packet with
+				 * anycast source address.  We should allow
+				 * to bind to a deprecated address, since
+				 * the application dare to use it.
+				 */
+				IFA_LOCK_SPIN(ifa);
+				if (((struct in6_ifaddr *)ifa)->ia6_flags &
+				    (IN6_IFF_ANYCAST | IN6_IFF_NOTREADY|
+				    IN6_IFF_DETACHED | IN6_IFF_CLAT46)) {
+					IFA_UNLOCK(ifa);
+					IFA_REMREF(ifa);
+					lck_rw_done(pcbinfo->ipi_lock);
+					socket_lock(so, 0);
+					return (EADDRNOTAVAIL);
+				}
+				/*
+				 * Opportunistically determine the outbound
+				 * interface that may be used; this may not
+				 * hold true if we end up using a route
+				 * going over a different interface, e.g.
+				 * when sending to a local address.  This
+				 * will get updated again after sending.
+				 */
+				outif = ifa->ifa_ifp;
+				IFA_UNLOCK(ifa);
+				IFA_REMREF(ifa);
 			}
-			ifafree(ia);
-			ia = NULL;
 		}
-		if (lport) {
+		if (lport != 0) {
 			struct inpcb *t;
-
-			/* GROSS */
-			if (ntohs(lport) < IPV6PORT_RESERVED && p &&
-                            ((so->so_state & SS_PRIV) == 0)) {
-				lck_rw_done(pcbinfo->mtx);
-				socket_lock(so, 0);
-				return(EACCES);
+			uid_t u;
+
+#if !CONFIG_EMBEDDED
+			if (ntohs(lport) < IPV6PORT_RESERVED &&
+				!IN6_IS_ADDR_UNSPECIFIED(&sin6.sin6_addr)) {
+				cred = kauth_cred_proc_ref(p);
+				error = priv_check_cred(cred,
+				    PRIV_NETINET_RESERVEDPORT, 0);
+				kauth_cred_unref(&cred);
+				if (error != 0) {
+					lck_rw_done(pcbinfo->ipi_lock);
+					socket_lock(so, 0);
+					return (EACCES);
+				}
 			}
-
-			if (so->so_uid &&
-			    !IN6_IS_ADDR_MULTICAST(&sin6->sin6_addr)) {
-				t = in6_pcblookup_local(pcbinfo,
-				    &sin6->sin6_addr, lport,
+#endif /* !CONFIG_EMBEDDED */
+			if (!IN6_IS_ADDR_MULTICAST(&sin6.sin6_addr) &&
+			    (u = kauth_cred_getuid(so->so_cred)) != 0) {
+				t = in6_pcblookup_local_and_cleanup(pcbinfo,
+				    &sin6.sin6_addr, lport,
 				    INPLOOKUP_WILDCARD);
-				if (t &&
-				    (!IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr) ||
-				     !IN6_IS_ADDR_UNSPECIFIED(&t->in6p_laddr) ||
-				     (t->inp_socket->so_options &
-				      SO_REUSEPORT) == 0) &&
-				    so->so_uid != t->inp_socket->so_uid) {
-					lck_rw_done(pcbinfo->mtx);
+				if (t != NULL && (!IN6_IS_ADDR_UNSPECIFIED(
+				    &sin6.sin6_addr) ||
+				    !IN6_IS_ADDR_UNSPECIFIED(&t->in6p_laddr) ||
+				    !(t->inp_socket->so_options &
+				    SO_REUSEPORT)) && (u != kauth_cred_getuid(
+				    t->inp_socket->so_cred)) &&
+				    !(t->inp_socket->so_flags &
+				    SOF_REUSESHAREUID)) {
+					lck_rw_done(pcbinfo->ipi_lock);
 					socket_lock(so, 0);
 					return (EADDRINUSE);
 				}
-				if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0 &&
-				    IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr)) {
+				if (!(inp->inp_flags & IN6P_IPV6_V6ONLY) &&
+				    IN6_IS_ADDR_UNSPECIFIED(&sin6.sin6_addr)) {
 					struct sockaddr_in sin;
 
-					in6_sin6_2_sin(&sin, sin6);
-					t = in_pcblookup_local(pcbinfo,
-						sin.sin_addr, lport,
-						INPLOOKUP_WILDCARD);
-					if (t &&
-					    (so->so_uid !=
-					     t->inp_socket->so_uid) &&
-					    (ntohl(t->inp_laddr.s_addr) !=
-					     INADDR_ANY ||
-					     INP_SOCKAF(so) ==
-					     INP_SOCKAF(t->inp_socket))) {
-
-						lck_rw_done(pcbinfo->mtx);
+					in6_sin6_2_sin(&sin, &sin6);
+					t = in_pcblookup_local_and_cleanup(
+					    pcbinfo, sin.sin_addr, lport,
+					    INPLOOKUP_WILDCARD);
+					if (t != NULL &&
+					    !(t->inp_socket->so_options &
+					    SO_REUSEPORT) &&
+					    (kauth_cred_getuid(so->so_cred) !=
+					    kauth_cred_getuid(t->inp_socket->
+					    so_cred)) && (t->inp_laddr.s_addr !=
+					    INADDR_ANY || SOCK_DOM(so) ==
+					    SOCK_DOM(t->inp_socket))) {
+						lck_rw_done(pcbinfo->ipi_lock);
 						socket_lock(so, 0);
 						return (EADDRINUSE);
 					}
 				}
 			}
-			t = in6_pcblookup_local(pcbinfo, &sin6->sin6_addr,
-						lport, wild);
-			if (t && (reuseport & t->inp_socket->so_options) == 0) {
-				lck_rw_done(pcbinfo->mtx);
+			t = in6_pcblookup_local_and_cleanup(pcbinfo,
+			    &sin6.sin6_addr, lport, wild);
+			if (t != NULL &&
+			    (reuseport & t->inp_socket->so_options) == 0) {
+				lck_rw_done(pcbinfo->ipi_lock);
 				socket_lock(so, 0);
-				return(EADDRINUSE);
+				return (EADDRINUSE);
 			}
-			if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0 &&
-			    IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr)) {
+			if (!(inp->inp_flags & IN6P_IPV6_V6ONLY) &&
+			    IN6_IS_ADDR_UNSPECIFIED(&sin6.sin6_addr)) {
 				struct sockaddr_in sin;
 
-				in6_sin6_2_sin(&sin, sin6);
-				t = in_pcblookup_local(pcbinfo, sin.sin_addr,
-						       lport, wild);
-				if (t &&
-				    (reuseport & t->inp_socket->so_options)
-				    == 0 &&
-				    (ntohl(t->inp_laddr.s_addr)
-				     != INADDR_ANY ||
-				     INP_SOCKAF(so) ==
-				     INP_SOCKAF(t->inp_socket))) {
-					lck_rw_done(pcbinfo->mtx);
+				in6_sin6_2_sin(&sin, &sin6);
+				t = in_pcblookup_local_and_cleanup(pcbinfo,
+				    sin.sin_addr, lport, wild);
+				if (t != NULL && (reuseport &
+				    t->inp_socket->so_options) == 0 &&
+				    (t->inp_laddr.s_addr != INADDR_ANY ||
+				    SOCK_DOM(so) == SOCK_DOM(t->inp_socket))) {
+					lck_rw_done(pcbinfo->ipi_lock);
 					socket_lock(so, 0);
 					return (EADDRINUSE);
 				}
 			}
 		}
-		inp->in6p_laddr = sin6->sin6_addr;
 	}
+
 	socket_lock(so, 0);
+	/*
+	 * We unlocked socket's protocol lock for a long time.
+	 * The socket might have been dropped/defuncted.
+	 * Checking if world has changed since.
+	 */
+	if (inp->inp_state == INPCB_STATE_DEAD) {
+		lck_rw_done(pcbinfo->ipi_lock);
+		return (ECONNABORTED);
+	}
+
+	/* check if the socket got bound when the lock was released */
+	if (inp->inp_lport || !IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr)) {
+		lck_rw_done(pcbinfo->ipi_lock);
+		return (EINVAL);
+	}
+
+	if (!IN6_IS_ADDR_UNSPECIFIED(&sin6.sin6_addr)) {
+		inp->in6p_laddr = sin6.sin6_addr;
+		inp->in6p_last_outifp = outif;
+	}
+
 	if (lport == 0) {
 		int e;
 		if ((e = in6_pcbsetport(&inp->in6p_laddr, inp, p, 1)) != 0) {
-			lck_rw_done(pcbinfo->mtx);
-			return(e);
+			/* Undo any address bind from above. */
+			inp->in6p_laddr = in6addr_any;
+			inp->in6p_last_outifp = NULL;	
+			lck_rw_done(pcbinfo->ipi_lock);
+			return (e);
 		}
-	}
-	else {
+	} else {
 		inp->inp_lport = lport;
 		if (in_pcbinshash(inp, 1) != 0) {
 			inp->in6p_laddr = in6addr_any;
 			inp->inp_lport = 0;
-			lck_rw_done(pcbinfo->mtx);
+			inp->in6p_last_outifp = NULL;
+			lck_rw_done(pcbinfo->ipi_lock);
 			return (EAGAIN);
 		}
-	}	
-	lck_rw_done(pcbinfo->mtx);
-	return(0);
+	}
+	lck_rw_done(pcbinfo->ipi_lock);
+	sflt_notify(so, sock_evt_bound, NULL);
+	return (0);
 }
 
 /*
- *   Transform old in6_pcbconnect() into an inner subroutine for new
- *   in6_pcbconnect(): Do some validity-checking on the remote
- *   address (in mbuf 'nam') and then determine local host address
- *   (i.e., which interface) to use to access that remote host.
+ * Transform old in6_pcbconnect() into an inner subroutine for new
+ * in6_pcbconnect(); do some validity-checking on the remote address
+ * (in "nam") and then determine local host address (i.e., which
+ * interface) to use to access that remote host.
+ *
+ * This routine may alter the caller-supplied remote address "nam".
  *
- *   This preserves definition of in6_pcbconnect(), while supporting a
- *   slightly different version for T/TCP.  (This is more than
- *   a bit of a kludge, but cleaning up the internal interfaces would
- *   have forced minor changes in every protocol).
+ * This routine might return an ifp with a reference held if the caller
+ * provides a non-NULL outif, even in the error case.  The caller is
+ * responsible for releasing its reference.
  */
-
 int
-in6_pcbladdr(
-	struct inpcb *inp,
-	struct sockaddr *nam,
-	struct in6_addr *plocal_addr6)
+in6_pcbladdr(struct inpcb *inp, struct sockaddr *nam,
+    struct in6_addr *plocal_addr6, struct ifnet **outif)
 {
-	struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)nam;
 	struct in6_addr *addr6 = NULL;
 	struct in6_addr src_storage;
-	
-	struct ifnet *ifp = NULL;
 	int error = 0;
+	unsigned int ifscope;
 
-	if (nam->sa_len != sizeof (*sin6))
+	if (outif != NULL)
+		*outif = NULL;
+	if (nam->sa_len != sizeof (struct sockaddr_in6))
 		return (EINVAL);
-	if (sin6->sin6_family != AF_INET6)
+	if (SIN6(nam)->sin6_family != AF_INET6)
 		return (EAFNOSUPPORT);
-	if (sin6->sin6_port == 0)
+	if (SIN6(nam)->sin6_port == 0)
 		return (EADDRNOTAVAIL);
 
 	/* KAME hack: embed scopeid */
-	if (in6_embedscope(&sin6->sin6_addr, sin6, inp, &ifp) != 0)
-		return EINVAL;
+	if (in6_embedscope(&SIN6(nam)->sin6_addr, SIN6(nam), inp, NULL, NULL) != 0)
+		return (EINVAL);
 
 	if (in6_ifaddrs) {
 		/*
 		 * If the destination address is UNSPECIFIED addr,
 		 * use the loopback addr, e.g ::1.
 		 */
-		if (IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr))
-			sin6->sin6_addr = in6addr_loopback;
+		if (IN6_IS_ADDR_UNSPECIFIED(&SIN6(nam)->sin6_addr))
+			SIN6(nam)->sin6_addr = in6addr_loopback;
 	}
-	{
+
+	ifscope = (inp->inp_flags & INP_BOUND_IF) ?
+	    inp->inp_boundifp->if_index : IFSCOPE_NONE;
+
+	/*
+	 * XXX: in6_selectsrc might replace the bound local address
+	 * with the address specified by setsockopt(IPV6_PKTINFO).
+	 * Is it the intended behavior?
+	 *
+	 * in6_selectsrc() might return outif with its reference held
+	 * even in the error case; caller always needs to release it
+	 * if non-NULL.
+	 */
+	addr6 = in6_selectsrc(SIN6(nam), inp->in6p_outputopts, inp,
+	    &inp->in6p_route, outif, &src_storage, ifscope, &error);
+
+	if (outif != NULL) {
+		struct rtentry *rt = inp->in6p_route.ro_rt;
 		/*
-		 * XXX: in6_selectsrc might replace the bound local address
-		 * with the address specified by setsockopt(IPV6_PKTINFO).
-		 * Is it the intended behavior?
+		 * If in6_selectsrc() returns a route, it should be one
+		 * which points to the same ifp as outif.  Just in case
+		 * it isn't, use the one from the route for consistency.
+		 * Otherwise if there is no route, leave outif alone as
+		 * it could still be useful to the caller.
 		 */
-		addr6 = in6_selectsrc(sin6, inp->in6p_outputopts,
-					      inp->in6p_moptions,
-					      &inp->in6p_route,
-					      &inp->in6p_laddr, &src_storage, &error);
-		if (addr6 == 0) {
-			if (error == 0)
-				error = EADDRNOTAVAIL;
-			return(error);
+		if (rt != NULL && rt->rt_ifp != *outif) {
+			ifnet_reference(rt->rt_ifp);	/* for caller */
+			if (*outif != NULL)
+				ifnet_release(*outif);
+			*outif = rt->rt_ifp;
 		}
-		*plocal_addr6 = *addr6;
-		/*
-		 * Don't do pcblookup call here; return interface in
-		 * plocal_addr6
-		 * and exit to caller, that will do the lookup.
-		 */
 	}
 
-	if (inp->in6p_route.ro_rt)
-		ifp = inp->in6p_route.ro_rt->rt_ifp;
+	if (addr6 == NULL) {
+		if (outif != NULL && (*outif) != NULL &&
+		    inp_restricted_send(inp, *outif)) {
+			soevent(inp->inp_socket,
+			    (SO_FILT_HINT_LOCKED | SO_FILT_HINT_IFDENIED));
+			error = EHOSTUNREACH;
+		}
+		if (error == 0)
+			error = EADDRNOTAVAIL;
+		return (error);
+	}
 
-	return(0);
+	*plocal_addr6 = *addr6;
+	/*
+	 * Don't do pcblookup call here; return interface in
+	 * plocal_addr6 and exit to caller, that will do the lookup.
+	 */
+	return (0);
 }
 
 /*
@@ -405,432 +524,300 @@ in6_pcbladdr(
  * then pick one.
  */
 int
-in6_pcbconnect(inp, nam, p)
-	struct inpcb *inp;
-	struct sockaddr *nam;
-	struct proc *p;
+in6_pcbconnect(struct inpcb *inp, struct sockaddr *nam, struct proc *p)
 {
 	struct in6_addr addr6;
-	struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)nam;
+	struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)(void *)nam;
 	struct inpcb *pcb;
-	int error;
+	int error = 0;
+	struct ifnet *outif = NULL;
+	struct socket *so = inp->inp_socket;
+
+#if CONTENT_FILTER
+	if (so)
+		so->so_state_change_cnt++;
+#endif
+
+	if (so->so_proto->pr_protocol == IPPROTO_UDP &&
+	    sin6->sin6_port == htons(53) && !(so->so_flags1 & SOF1_DNS_COUNTED)) {
+	    	so->so_flags1 |= SOF1_DNS_COUNTED;
+		INC_ATOMIC_INT64_LIM(net_api_stats.nas_socket_inet_dgram_dns);
+	}
 
 	/*
 	 * Call inner routine, to assign local interface address.
 	 * in6_pcbladdr() may automatically fill in sin6_scope_id.
+	 *
+	 * in6_pcbladdr() might return an ifp with its reference held
+	 * even in the error case, so make sure that it's released
+	 * whenever it's non-NULL.
 	 */
-	if ((error = in6_pcbladdr(inp, nam, &addr6)) != 0)
-		return(error);
-	socket_unlock(inp->inp_socket, 0);
+	if ((error = in6_pcbladdr(inp, nam, &addr6, &outif)) != 0) {
+		if (outif != NULL && inp_restricted_send(inp, outif)) 
+			soevent(so,
+			    (SO_FILT_HINT_LOCKED | SO_FILT_HINT_IFDENIED));
+		goto done;
+	}
+	socket_unlock(so, 0);
 	pcb = in6_pcblookup_hash(inp->inp_pcbinfo, &sin6->sin6_addr,
-			       sin6->sin6_port,
-			      IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr)
-			      ? &addr6 : &inp->in6p_laddr,
-			      inp->inp_lport, 0, NULL);
-	socket_lock(inp->inp_socket, 0);
+	    sin6->sin6_port, IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr) ?
+	    &addr6 : &inp->in6p_laddr, inp->inp_lport, 0, NULL);
+	socket_lock(so, 0);
 	if (pcb != NULL) {
-		in_pcb_checkstate(pcb, WNT_RELEASE, 0);
-		return (EADDRINUSE);
+		in_pcb_checkstate(pcb, WNT_RELEASE, pcb == inp ? 1 : 0);
+		error = EADDRINUSE;
+		goto done;
 	}
 	if (IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr)) {
 		if (inp->inp_lport == 0) {
-			error = in6_pcbbind(inp, (struct sockaddr *)0, p);
+			error = in6_pcbbind(inp, NULL, p);
 			if (error)
-				return (error);
+				goto done;
 		}
 		inp->in6p_laddr = addr6;
+		inp->in6p_last_outifp = outif;	/* no reference needed */
+		inp->in6p_flags |= INP_IN6ADDR_ANY;
 	}
-	if (!lck_rw_try_lock_exclusive(inp->inp_pcbinfo->mtx)) {
-		/*lock inversion issue, mostly with udp multicast packets */
-		socket_unlock(inp->inp_socket, 0);
-		lck_rw_lock_exclusive(inp->inp_pcbinfo->mtx);
-		socket_lock(inp->inp_socket, 0);
+	if (!lck_rw_try_lock_exclusive(inp->inp_pcbinfo->ipi_lock)) {
+		/* lock inversion issue, mostly with udp multicast packets */
+		socket_unlock(so, 0);
+		lck_rw_lock_exclusive(inp->inp_pcbinfo->ipi_lock);
+		socket_lock(so, 0);
 	}
 	inp->in6p_faddr = sin6->sin6_addr;
 	inp->inp_fport = sin6->sin6_port;
-	/* update flowinfo - draft-itojun-ipv6-flowlabel-api-00 */
-	inp->in6p_flowinfo &= ~IPV6_FLOWLABEL_MASK;
-	if (inp->in6p_flags & IN6P_AUTOFLOWLABEL)
-		inp->in6p_flowinfo |=
-		    (htonl(ip6_flow_seq++) & IPV6_FLOWLABEL_MASK);
-
+	if (nstat_collect && SOCK_PROTO(so) == IPPROTO_UDP)
+		nstat_pcb_invalidate_cache(inp);
 	in_pcbrehash(inp);
-	lck_rw_done(inp->inp_pcbinfo->mtx);
-	return (0);
-}
+	lck_rw_done(inp->inp_pcbinfo->ipi_lock);
 
-#if 0
-/*
- * Return an IPv6 address, which is the most appropriate for given
- * destination and user specified options.
- * If necessary, this function lookups the routing table and return
- * an entry to the caller for later use.
- */
-struct in6_addr *
-in6_selectsrc(
-	struct sockaddr_in6 *dstsock,
-	struct ip6_pktopts *opts,
-	struct ip6_moptions *mopts,
-	struct route_in6 *ro,
-	struct in6_addr *laddr,
-	struct in6_addr *src_storage,
-	int *errorp)
-{
-	struct in6_addr *dst;
-	struct in6_ifaddr *ia6 = 0;
-	struct in6_pktinfo *pi = NULL;
-
-	dst = &dstsock->sin6_addr;
-	*errorp = 0;
-
-	/*
-	 * If the source address is explicitly specified by the caller,
-	 * use it.
-	 */
-	if (opts && (pi = opts->ip6po_pktinfo) &&
-	    !IN6_IS_ADDR_UNSPECIFIED(&pi->ipi6_addr))
-		return(&pi->ipi6_addr);
-
-	/*
-	 * If the source address is not specified but the socket(if any)
-	 * is already bound, use the bound address.
-	 */
-	if (laddr && !IN6_IS_ADDR_UNSPECIFIED(laddr))
-		return(laddr);
-
-	/*
-	 * If the caller doesn't specify the source address but
-	 * the outgoing interface, use an address associated with
-	 * the interface.
-	 */
-	if (pi && pi->ipi6_ifindex) {
-		/* XXX boundary check is assumed to be already done. */
-		ia6 = in6_ifawithscope(ifindex2ifnet[pi->ipi6_ifindex],
-				       dst);
-		if (ia6 == 0) {
-			*errorp = EADDRNOTAVAIL;
-			return(0);
-		}
-		*src_storage = satosin6(&ia6->ia_addr)->sin6_addr;
-		ifafree(&ia6->ia_ifa);
-		return(src_storage);
-	}
-
-	/*
-	 * If the destination address is a link-local unicast address or
-	 * a multicast address, and if the outgoing interface is specified
-	 * by the sin6_scope_id filed, use an address associated with the
-	 * interface.
-	 * XXX: We're now trying to define more specific semantics of
-	 *      sin6_scope_id field, so this part will be rewritten in
-	 *      the near future.
-	 */
-	if ((IN6_IS_ADDR_LINKLOCAL(dst) || IN6_IS_ADDR_MULTICAST(dst)) &&
-	    dstsock->sin6_scope_id) {
-		/*
-		 * I'm not sure if boundary check for scope_id is done
-		 * somewhere...
-		 */
-		if (dstsock->sin6_scope_id < 0 ||
-		    if_index < dstsock->sin6_scope_id) {
-			*errorp = ENXIO; /* XXX: better error? */
-			return(0);
-		}
-		ia6 = in6_ifawithscope(ifindex2ifnet[dstsock->sin6_scope_id],
-				       dst);
-		if (ia6 == 0) {
-			*errorp = EADDRNOTAVAIL;
-			return(0);
-		}
-		*src_storage = satosin6(&ia6->ia_addr)->sin6_addr;
-		ifafree(&ia6->ia_ifa);
-		return(src_storage);
-	}
-
-	/*
-	 * If the destination address is a multicast address and
-	 * the outgoing interface for the address is specified
-	 * by the caller, use an address associated with the interface.
-	 * There is a sanity check here; if the destination has node-local
-	 * scope, the outgoing interfacde should be a loopback address.
-	 * Even if the outgoing interface is not specified, we also
-	 * choose a loopback interface as the outgoing interface.
-	 */
-	if (IN6_IS_ADDR_MULTICAST(dst)) {
-		struct ifnet *ifp = mopts ? mopts->im6o_multicast_ifp : NULL;
-
-		if (ifp == NULL && IN6_IS_ADDR_MC_NODELOCAL(dst)) {
-			ifp = &loif[0];
-		}
-
-		if (ifp) {
-			ia6 = in6_ifawithscope(ifp, dst);
-			if (ia6 == 0) {
-				*errorp = EADDRNOTAVAIL;
-				return(0);
-			}
-			*src_storage = ia6->ia_addr.sin6_addr;
-			ifafree(&ia6->ia_ifa);
-			return(src_storage);
-		}
-	}
-
-	/*
-	 * If the next hop address for the packet is specified
-	 * by caller, use an address associated with the route
-	 * to the next hop.
-	 */
-	{
-		struct sockaddr_in6 *sin6_next;
-		struct rtentry *rt;
-
-		if (opts && opts->ip6po_nexthop) {
-			sin6_next = satosin6(opts->ip6po_nexthop);
-			rt = nd6_lookup(&sin6_next->sin6_addr, 1, NULL, 0);
-			if (rt) {
-				ia6 = in6_ifawithscope(rt->rt_ifp, dst);
-				if (ia6 == 0) {
-					ifaref(&rt->rt_ifa);
-					ia6 = ifatoia6(rt->rt_ifa);
-				}
-			}
-			if (ia6 == 0) {
-				*errorp = EADDRNOTAVAIL;
-				return(0);
-			}
-			*src_storage = satosin6(&ia6->ia_addr)->sin6_addr;
-			ifaref(&rt->rt_ifa);
-			return(src_storage);
-		}
-	}
-
-	/*
-	 * If route is known or can be allocated now,
-	 * our src addr is taken from the i/f, else punt.
-	 */
-	if (ro) {
-		if (ro->ro_rt &&
-		    !IN6_ARE_ADDR_EQUAL(&satosin6(&ro->ro_dst)->sin6_addr, dst)) {
-			rtfree(ro->ro_rt);
-			ro->ro_rt = (struct rtentry *)0;
-		}
-		if (ro->ro_rt == (struct rtentry *)0 ||
-		    ro->ro_rt->rt_ifp == (struct ifnet *)0) {
-			struct sockaddr_in6 *dst6;
-
-			/* No route yet, so try to acquire one */
-			bzero(&ro->ro_dst, sizeof(struct sockaddr_in6));
-			dst6 = (struct sockaddr_in6 *)&ro->ro_dst;
-			dst6->sin6_family = AF_INET6;
-			dst6->sin6_len = sizeof(struct sockaddr_in6);
-			dst6->sin6_addr = *dst;
-			if (IN6_IS_ADDR_MULTICAST(dst)) {
-				ro->ro_rt = rtalloc1(&((struct route *)ro)
-						     ->ro_dst, 0, 0UL);
-			} else {
-				rtalloc((struct route *)ro);
-			}
-		}
-
-		/*
-		 * in_pcbconnect() checks out IFF_LOOPBACK to skip using
-		 * the address. But we don't know why it does so.
-		 * It is necessary to ensure the scope even for lo0
-		 * so doesn't check out IFF_LOOPBACK.
-		 */
-
-		if (ro->ro_rt) {
-			ia6 = in6_ifawithscope(ro->ro_rt->rt_ifa->ifa_ifp, dst);
-			if (ia6 == 0) { /* xxx scope error ?*/
-				ifaref(ro->ro_rt->rt_ifa);
-				ia6 = ifatoia6(ro->ro_rt->rt_ifa);
-			}
-		}
-		if (ia6 == 0) {
-			*errorp = EHOSTUNREACH;	/* no route */
-			return(0);
-		}
-		*src_storage = satosin6(&ia6->ia_addr)->sin6_addr;
-		ifaref(&rt->rt_ifa);
-		return(src_storage);
-	}
+done:
+	if (outif != NULL)
+		ifnet_release(outif);
 
-	*errorp = EADDRNOTAVAIL;
-	return(0);
+	return (error);
 }
 
-/*
- * Default hop limit selection. The precedence is as follows:
- * 1. Hoplimit valued specified via ioctl.
- * 2. (If the outgoing interface is detected) the current
- *     hop limit of the interface specified by router advertisement.
- * 3. The system default hoplimit.
-*/
-int
-in6_selecthlim(
-	struct in6pcb *in6p,
-	struct ifnet *ifp)
+void
+in6_pcbdisconnect(struct inpcb *inp)
 {
-	if (in6p && in6p->in6p_hops >= 0)
-		return(in6p->in6p_hops);
-	else if (ifp)
-		return(nd_ifinfo[ifp->if_index].chlim);
-	else
-		return(ip6_defhlim);
-}
+	struct socket *so = inp->inp_socket;
+
+#if CONTENT_FILTER
+	if (so)
+		so->so_state_change_cnt++;
 #endif
 
-void
-in6_pcbdisconnect(inp)
-	struct inpcb *inp;
-{
-	if (!lck_rw_try_lock_exclusive(inp->inp_pcbinfo->mtx)) {
-		/*lock inversion issue, mostly with udp multicast packets */
-		socket_unlock(inp->inp_socket, 0);
-		lck_rw_lock_exclusive(inp->inp_pcbinfo->mtx);
-		socket_lock(inp->inp_socket, 0);
+	if (!lck_rw_try_lock_exclusive(inp->inp_pcbinfo->ipi_lock)) {
+		/* lock inversion issue, mostly with udp multicast packets */
+		socket_unlock(so, 0);
+		lck_rw_lock_exclusive(inp->inp_pcbinfo->ipi_lock);
+		socket_lock(so, 0);
 	}
-	bzero((caddr_t)&inp->in6p_faddr, sizeof(inp->in6p_faddr));
+	if (nstat_collect && SOCK_PROTO(so) == IPPROTO_UDP)
+		nstat_pcb_cache(inp);
+	bzero((caddr_t)&inp->in6p_faddr, sizeof (inp->in6p_faddr));
 	inp->inp_fport = 0;
-	/* clear flowinfo - draft-itojun-ipv6-flowlabel-api-00 */
-	inp->in6p_flowinfo &= ~IPV6_FLOWLABEL_MASK;
+	/* clear flowinfo - RFC 6437 */
+	inp->inp_flow &= ~IPV6_FLOWLABEL_MASK;
 	in_pcbrehash(inp);
-	lck_rw_done(inp->inp_pcbinfo->mtx);
-	if (inp->inp_socket->so_state & SS_NOFDREF)
+	lck_rw_done(inp->inp_pcbinfo->ipi_lock);
+	/*
+	 * A multipath subflow socket would have its SS_NOFDREF set by default,
+	 * so check for SOF_MP_SUBFLOW socket flag before detaching the PCB;
+	 * when the socket is closed for real, SOF_MP_SUBFLOW would be cleared.
+	 */
+	if (!(so->so_flags & SOF_MP_SUBFLOW) && (so->so_state & SS_NOFDREF))
 		in6_pcbdetach(inp);
 }
 
 void
-in6_pcbdetach(inp)
-	struct inpcb *inp;
+in6_pcbdetach(struct inpcb *inp)
 {
 	struct socket *so = inp->inp_socket;
-	struct inpcbinfo *ipi = inp->inp_pcbinfo;
+
+	if (so->so_pcb == NULL) {
+		/* PCB has been disposed */
+		panic("%s: inp=%p so=%p proto=%d so_pcb is null!\n", __func__,
+		    inp, so, SOCK_PROTO(so));
+		/* NOTREACHED */
+	}
 
 #if IPSEC
 	if (inp->in6p_sp != NULL) {
-		lck_mtx_lock(sadb_mutex);
-		ipsec6_delete_pcbpolicy(inp);
-		lck_mtx_unlock(sadb_mutex);
+		(void) ipsec6_delete_pcbpolicy(inp);
 	}
 #endif /* IPSEC */
 
-	if (in_pcb_checkstate(inp, WNT_STOPUSING, 1) != WNT_STOPUSING)
-		printf("in6_pcbdetach so=%x can't be marked dead ok\n", so);
+	if (inp->inp_stat != NULL && SOCK_PROTO(so) == IPPROTO_UDP) {
+		if (inp->inp_stat->rxpackets == 0 && inp->inp_stat->txpackets == 0) {
+			INC_ATOMIC_INT64_LIM(net_api_stats.nas_socket_inet6_dgram_no_data);
+		}
+	}
 
-	inp->inp_state = INPCB_STATE_DEAD;
+	/*
+	 * Let NetworkStatistics know this PCB is going away
+	 * before we detach it.
+	 */
+	if (nstat_collect &&
+	    (SOCK_PROTO(so) == IPPROTO_TCP || SOCK_PROTO(so) == IPPROTO_UDP))
+		nstat_pcb_detach(inp);
+	/* mark socket state as dead */
+	if (in_pcb_checkstate(inp, WNT_STOPUSING, 1) != WNT_STOPUSING) {
+		panic("%s: so=%p proto=%d couldn't set to STOPUSING\n",
+		    __func__, so, SOCK_PROTO(so));
+		/* NOTREACHED */
+	}
+
+	if (!(so->so_flags & SOF_PCBCLEARING)) {
+		struct ip_moptions *imo;
+		struct ip6_moptions *im6o;
 
-	if ((so->so_flags & SOF_PCBCLEARING) == 0) {
 		inp->inp_vflag = 0;
-		so->so_flags |= SOF_PCBCLEARING;
-		inp->inp_gencnt = ++ipi->ipi_gencnt;
-		if (inp->in6p_options)
+		if (inp->in6p_options != NULL) {
 			m_freem(inp->in6p_options);
- 		ip6_freepcbopts(inp->in6p_outputopts);
- 		ip6_freemoptions(inp->in6p_moptions);
-		if (inp->in6p_route.ro_rt)
-			rtfree(inp->in6p_route.ro_rt);
-		/* Check and free IPv4 related resources in case of mapped addr */
-		if (inp->inp_options)
-			(void)m_free(inp->inp_options);
- 		ip_freemoptions(inp->inp_moptions);
+			inp->in6p_options = NULL;
+		}
+		ip6_freepcbopts(inp->in6p_outputopts);
+		ROUTE_RELEASE(&inp->in6p_route);
+		/* free IPv4 related resources in case of mapped addr */
+		if (inp->inp_options != NULL) {
+			(void) m_free(inp->inp_options);
+			inp->inp_options = NULL;
+		}
+		im6o = inp->in6p_moptions;
+		inp->in6p_moptions = NULL;
+
+		imo = inp->inp_moptions;
 		inp->inp_moptions = NULL;
-	
+
+		sofreelastref(so, 0);
+		inp->inp_state = INPCB_STATE_DEAD;
+		/* makes sure we're not called twice from so_close */
+		so->so_flags |= SOF_PCBCLEARING;
+
+		inpcb_gc_sched(inp->inp_pcbinfo, INPCB_TIMER_FAST);
+
+		/*
+		 * See inp_join_group() for why we need to unlock
+		 */
+		if (im6o != NULL || imo != NULL) {
+			socket_unlock(so, 0);
+			if (im6o != NULL)
+				IM6O_REMREF(im6o);
+			if (imo != NULL)
+				IMO_REMREF(imo);
+			socket_lock(so, 0);
+		}
 	}
 }
 
 struct sockaddr *
-in6_sockaddr(port, addr_p)
-	in_port_t port;
-	struct in6_addr *addr_p;
+in6_sockaddr(in_port_t port, struct in6_addr *addr_p)
 {
 	struct sockaddr_in6 *sin6;
 
-	MALLOC(sin6, struct sockaddr_in6 *, sizeof *sin6, M_SONAME, M_WAITOK);
-	bzero(sin6, sizeof *sin6);
+	MALLOC(sin6, struct sockaddr_in6 *, sizeof (*sin6), M_SONAME, M_WAITOK);
+	if (sin6 == NULL)
+		return (NULL);
+	bzero(sin6, sizeof (*sin6));
 	sin6->sin6_family = AF_INET6;
-	sin6->sin6_len = sizeof(*sin6);
+	sin6->sin6_len = sizeof (*sin6);
 	sin6->sin6_port = port;
 	sin6->sin6_addr = *addr_p;
+
+	/* would be good to use sa6_recoverscope(), except for locking  */
 	if (IN6_IS_SCOPE_LINKLOCAL(&sin6->sin6_addr))
 		sin6->sin6_scope_id = ntohs(sin6->sin6_addr.s6_addr16[1]);
 	else
-		sin6->sin6_scope_id = 0;	/*XXX*/
+		sin6->sin6_scope_id = 0;	/* XXX */
 	if (IN6_IS_SCOPE_LINKLOCAL(&sin6->sin6_addr))
 		sin6->sin6_addr.s6_addr16[1] = 0;
 
-	return (struct sockaddr *)sin6;
+	return ((struct sockaddr *)sin6);
 }
 
-struct sockaddr *
-in6_v4mapsin6_sockaddr(port, addr_p)
-	in_port_t port;
-	struct in_addr *addr_p;
+void
+in6_sockaddr_s(in_port_t port, struct in6_addr *addr_p,
+    struct sockaddr_in6 *sin6)
 {
-	struct sockaddr_in sin;
-	struct sockaddr_in6 *sin6_p;
-
-	bzero(&sin, sizeof sin);
-	sin.sin_family = AF_INET;
-	sin.sin_len = sizeof(sin);
-	sin.sin_port = port;
-	sin.sin_addr = *addr_p;
-
-	MALLOC(sin6_p, struct sockaddr_in6 *, sizeof *sin6_p, M_SONAME,
-		M_WAITOK);
-	in6_sin_2_v4mapsin6(&sin, sin6_p);
+	bzero(sin6, sizeof (*sin6));
+	sin6->sin6_family = AF_INET6;
+	sin6->sin6_len = sizeof (*sin6);
+	sin6->sin6_port = port;
+	sin6->sin6_addr = *addr_p;
 
-	return (struct sockaddr *)sin6_p;
+	/* would be good to use sa6_recoverscope(), except for locking  */
+	if (IN6_IS_SCOPE_LINKLOCAL(&sin6->sin6_addr))
+		sin6->sin6_scope_id = ntohs(sin6->sin6_addr.s6_addr16[1]);
+	else
+		sin6->sin6_scope_id = 0;	/* XXX */
+	if (IN6_IS_SCOPE_LINKLOCAL(&sin6->sin6_addr))
+		sin6->sin6_addr.s6_addr16[1] = 0;
 }
 
 /*
- * The calling convention of in6_setsockaddr() and in6_setpeeraddr() was
+ * The calling convention of in6_getsockaddr() and in6_getpeeraddr() was
  * modified to match the pru_sockaddr() and pru_peeraddr() entry points
  * in struct pr_usrreqs, so that protocols can just reference then directly
- * without the need for a wrapper function.  The socket must have a valid
- * (i.e., non-nil) PCB, but it should be impossible to get an invalid one
- * except through a kernel programming error, so it is acceptable to panic
- * (or in this case trap) if the PCB is invalid.  (Actually, we don't trap
- * because there actually /is/ a programming error somewhere... XXX)
+ * without the need for a wrapper function.
  */
 int
-in6_setsockaddr(so, nam)
-	struct socket *so;
-	struct sockaddr **nam;
+in6_getsockaddr(struct socket *so, struct sockaddr **nam)
 {
 	struct inpcb *inp;
 	struct in6_addr addr;
 	in_port_t port;
 
-	inp = sotoinpcb(so);
-	if (!inp) {
-		return EINVAL;
-	}
+	if ((inp = sotoinpcb(so)) == NULL)
+		return (EINVAL);
+
 	port = inp->inp_lport;
 	addr = inp->in6p_laddr;
 
 	*nam = in6_sockaddr(port, &addr);
-	return 0;
+	if (*nam == NULL)
+		return (ENOBUFS);
+	return (0);
 }
 
 int
-in6_setpeeraddr(so, nam)
-	struct socket *so;
-	struct sockaddr **nam;
+in6_getsockaddr_s(struct socket *so, struct sockaddr_in6 *ss)
 {
 	struct inpcb *inp;
 	struct in6_addr addr;
 	in_port_t port;
 
-	inp = sotoinpcb(so);
-	if (!inp) {
-		return EINVAL;
-	}
+	VERIFY(ss != NULL);
+	bzero(ss, sizeof (*ss));
+
+	if ((inp = sotoinpcb(so)) == NULL)
+		return (EINVAL);
+
+	port = inp->inp_lport;
+	addr = inp->in6p_laddr;
+
+	in6_sockaddr_s(port, &addr, ss);
+	return (0);
+}
+
+int
+in6_getpeeraddr(struct socket *so, struct sockaddr **nam)
+{
+	struct inpcb *inp;
+	struct in6_addr addr;
+	in_port_t port;
+
+	if ((inp = sotoinpcb(so)) == NULL)
+		return (EINVAL);
+
 	port = inp->inp_fport;
 	addr = inp->in6p_faddr;
 
 	*nam = in6_sockaddr(port, &addr);
-	return 0;
+	if (*nam == NULL)
+		return (ENOBUFS);
+	return (0);
 }
 
 int
@@ -840,16 +827,16 @@ in6_mapped_sockaddr(struct socket *so, struct sockaddr **nam)
 	int	error;
 
 	if (inp == NULL)
-		return EINVAL;
+		return (EINVAL);
 	if (inp->inp_vflag & INP_IPV4) {
-		error = in_setsockaddr(so, nam);
+		error = in_getsockaddr(so, nam);
 		if (error == 0)
-			in6_sin_2_v4mapsin6_in_sock(nam);
-	} else
-	/* scope issues will be handled in in6_setsockaddr(). */
-	error = in6_setsockaddr(so, nam);
-
-	return error;
+			error = in6_sin_2_v4mapsin6_in_sock(nam);
+	} else {
+		/* scope issues will be handled in in6_getsockaddr(). */
+		error = in6_getsockaddr(so, nam);
+	}
+	return (error);
 }
 
 int
@@ -859,16 +846,16 @@ in6_mapped_peeraddr(struct socket *so, struct sockaddr **nam)
 	int	error;
 
 	if (inp == NULL)
-		return EINVAL;
+		return (EINVAL);
 	if (inp->inp_vflag & INP_IPV4) {
-		error = in_setpeeraddr(so, nam);
+		error = in_getpeeraddr(so, nam);
 		if (error == 0)
-			in6_sin_2_v4mapsin6_in_sock(nam);
-	} else
-	/* scope issues will be handled in in6_setpeeraddr(). */
-	error = in6_setpeeraddr(so, nam);
-
-	return error;
+			error = in6_sin_2_v4mapsin6_in_sock(nam);
+	} else {
+		/* scope issues will be handled in in6_getpeeraddr(). */
+		error = in6_getpeeraddr(so, nam);
+	}
+	return (error);
 }
 
 /*
@@ -879,37 +866,31 @@ in6_mapped_peeraddr(struct socket *so, struct sockaddr **nam)
  * cmds that are uninteresting (e.g., no error in the map).
  * Call the protocol specific routine (if any) to report
  * any errors for each matching socket.
- *
- * Must be called at splnet.
  */
 void
-in6_pcbnotify(pcbinfo, dst, fport_arg, src, lport_arg, cmd, notify)
-	struct inpcbinfo *pcbinfo;
-	struct sockaddr *dst;
-	const struct sockaddr *src;
-	u_int fport_arg, lport_arg;
-	int cmd;
-//	struct inpcb *(*notify)(struct inpcb *, int);
-	void (*notify)(struct inpcb *, int);
+in6_pcbnotify(struct inpcbinfo *pcbinfo, struct sockaddr *dst, u_int fport_arg,
+    const struct sockaddr *src, u_int lport_arg, int cmd, void *cmdarg,
+    void (*notify)(struct inpcb *, int))
 {
+	struct inpcbhead *head = pcbinfo->ipi_listhead;
 	struct inpcb *inp, *ninp;
 	struct sockaddr_in6 sa6_src, *sa6_dst;
 	u_short	fport = fport_arg, lport = lport_arg;
 	u_int32_t flowinfo;
 	int errno;
-	struct inpcbhead *head = pcbinfo->listhead;
 
-	if ((unsigned)cmd > PRC_NCMDS || dst->sa_family != AF_INET6)
+	if ((unsigned)cmd >= PRC_NCMDS || dst->sa_family != AF_INET6)
 		return;
 
-	sa6_dst = (struct sockaddr_in6 *)dst;
+	sa6_dst = (struct sockaddr_in6 *)(void *)dst;
 	if (IN6_IS_ADDR_UNSPECIFIED(&sa6_dst->sin6_addr))
 		return;
 
 	/*
 	 * note that src can be NULL when we get notify by local fragmentation.
 	 */
-	sa6_src = (src == NULL) ? sa6_any : *(const struct sockaddr_in6 *)src;
+	sa6_src = (src == NULL) ?
+	    sa6_any : *(struct sockaddr_in6 *)(uintptr_t)(size_t)src;
 	flowinfo = sa6_src.sin6_flowinfo;
 
 	/*
@@ -923,19 +904,32 @@ in6_pcbnotify(pcbinfo, dst, fport_arg, src, lport_arg, cmd, notify)
 	if (PRC_IS_REDIRECT(cmd) || cmd == PRC_HOSTDEAD) {
 		fport = 0;
 		lport = 0;
-		bzero((caddr_t)&sa6_src.sin6_addr, sizeof(sa6_src.sin6_addr));
+		bzero((caddr_t)&sa6_src.sin6_addr, sizeof (sa6_src.sin6_addr));
 
 		if (cmd != PRC_HOSTDEAD)
 			notify = in6_rtchange;
 	}
 	errno = inet6ctlerrmap[cmd];
-	lck_rw_lock_shared(pcbinfo->mtx);
- 	for (inp = LIST_FIRST(head); inp != NULL; inp = ninp) {
- 		ninp = LIST_NEXT(inp, inp_list);
+	lck_rw_lock_shared(pcbinfo->ipi_lock);
+	for (inp = LIST_FIRST(head); inp != NULL; inp = ninp) {
+		ninp = LIST_NEXT(inp, inp_list);
 
- 		if ((inp->inp_vflag & INP_IPV6) == 0)
+		if (!(inp->inp_vflag & INP_IPV6))
 			continue;
 
+		/*
+		 * If the error designates a new path MTU for a destination
+		 * and the application (associated with this socket) wanted to
+		 * know the value, notify. Note that we notify for all
+		 * disconnected sockets if the corresponding application
+		 * wanted. This is because some UDP applications keep sending
+		 * sockets disconnected.
+		 * XXX: should we avoid to notify the value to TCP sockets?
+		 */
+		if (cmd == PRC_MSGSIZE)
+			ip6_notify_pmtu(inp, (struct sockaddr_in6 *)(void *)dst,
+			    (u_int32_t *)cmdarg);
+
 		/*
 		 * Detect if we should notify the error. If no source and
 		 * destination ports are specifed, but non-zero flowinfo and
@@ -946,46 +940,44 @@ in6_pcbnotify(pcbinfo, dst, fport_arg, src, lport_arg, cmd, notify)
 		 */
 		if (lport == 0 && fport == 0 && flowinfo &&
 		    inp->inp_socket != NULL &&
-		    flowinfo == (inp->in6p_flowinfo & IPV6_FLOWLABEL_MASK) &&
+		    flowinfo == (inp->inp_flow & IPV6_FLOWLABEL_MASK) &&
 		    IN6_ARE_ADDR_EQUAL(&inp->in6p_laddr, &sa6_src.sin6_addr))
 			goto do_notify;
 		else if (!IN6_ARE_ADDR_EQUAL(&inp->in6p_faddr,
-					     &sa6_dst->sin6_addr) ||
-			 inp->inp_socket == 0 ||
-			 (lport && inp->inp_lport != lport) ||
-			 (!IN6_IS_ADDR_UNSPECIFIED(&sa6_src.sin6_addr) &&
-			  !IN6_ARE_ADDR_EQUAL(&inp->in6p_laddr,
-					      &sa6_src.sin6_addr)) ||
-			 (fport && inp->inp_fport != fport)) 
+		    &sa6_dst->sin6_addr) || inp->inp_socket == NULL ||
+		    (lport && inp->inp_lport != lport) ||
+		    (!IN6_IS_ADDR_UNSPECIFIED(&sa6_src.sin6_addr) &&
+		    !IN6_ARE_ADDR_EQUAL(&inp->in6p_laddr,
+		    &sa6_src.sin6_addr)) || (fport && inp->inp_fport != fport))
 			continue;
-		     
 
-	  do_notify:
+do_notify:
 		if (notify) {
-			if (in_pcb_checkstate(inp, WNT_ACQUIRE, 0) == WNT_STOPUSING)
+			if (in_pcb_checkstate(inp, WNT_ACQUIRE, 0) ==
+			    WNT_STOPUSING)
 				continue;
 			socket_lock(inp->inp_socket, 1);
 			(*notify)(inp, errno);
-			(void)in_pcb_checkstate(inp, WNT_RELEASE, 1);
+			(void) in_pcb_checkstate(inp, WNT_RELEASE, 1);
 			socket_unlock(inp->inp_socket, 1);
 		}
 	}
-	lck_rw_done(pcbinfo->mtx);
+	lck_rw_done(pcbinfo->ipi_lock);
 }
 
 /*
  * Lookup a PCB based on the local address and port.
  */
 struct inpcb *
-in6_pcblookup_local(pcbinfo, laddr, lport_arg, wild_okay)
-	struct inpcbinfo *pcbinfo;
-	struct in6_addr *laddr;
-	u_int lport_arg;
-	int wild_okay;
+in6_pcblookup_local(struct inpcbinfo *pcbinfo, struct in6_addr *laddr,
+    u_int lport_arg, int wild_okay)
 {
 	struct inpcb *inp;
 	int matchwild = 3, wildcard;
 	u_short lport = lport_arg;
+	struct inpcbporthead *porthash;
+	struct inpcb *match = NULL;
+	struct inpcbport *phd;
 
 	if (!wild_okay) {
 		struct inpcbhead *head;
@@ -993,10 +985,10 @@ in6_pcblookup_local(pcbinfo, laddr, lport_arg, wild_okay)
 		 * Look for an unconnected (wildcard foreign addr) PCB that
 		 * matches the local address and port we're looking for.
 		 */
-		head = &pcbinfo->hashbase[INP_PCBHASH(INADDR_ANY, lport, 0,
-						      pcbinfo->hashmask)];
+		head = &pcbinfo->ipi_hashbase[INP_PCBHASH(INADDR_ANY, lport, 0,
+		    pcbinfo->ipi_hashmask)];
 		LIST_FOREACH(inp, head, inp_hash) {
-			if ((inp->inp_vflag & INP_IPV6) == 0)
+			if (!(inp->inp_vflag & INP_IPV6))
 				continue;
 			if (IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr) &&
 			    IN6_ARE_ADDR_EQUAL(&inp->in6p_laddr, laddr) &&
@@ -1011,97 +1003,51 @@ in6_pcblookup_local(pcbinfo, laddr, lport_arg, wild_okay)
 		 * Not found.
 		 */
 		return (NULL);
-	} else {
-		struct inpcbporthead *porthash;
-		struct inpcbport *phd;
-		struct inpcb *match = NULL;
+	}
+	/*
+	 * Best fit PCB lookup.
+	 *
+	 * First see if this local port is in use by looking on the
+	 * port hash list.
+	 */
+	porthash = &pcbinfo->ipi_porthashbase[INP_PCBPORTHASH(lport,
+	    pcbinfo->ipi_porthashmask)];
+	LIST_FOREACH(phd, porthash, phd_hash) {
+		if (phd->phd_port == lport)
+			break;
+	}
+	if (phd != NULL) {
 		/*
-		 * Best fit PCB lookup.
-		 *
-		 * First see if this local port is in use by looking on the
-		 * port hash list.
+		 * Port is in use by one or more PCBs. Look for best
+		 * fit.
 		 */
-		porthash = &pcbinfo->porthashbase[INP_PCBPORTHASH(lport,
-		    pcbinfo->porthashmask)];
-		LIST_FOREACH(phd, porthash, phd_hash) {
-			if (phd->phd_port == lport)
-				break;
-		}
-		if (phd != NULL) {
-			/*
-			 * Port is in use by one or more PCBs. Look for best
-			 * fit.
-			 */
-			LIST_FOREACH(inp, &phd->phd_pcblist, inp_portlist) {
-				wildcard = 0;
-				if ((inp->inp_vflag & INP_IPV6) == 0)
+		LIST_FOREACH(inp, &phd->phd_pcblist, inp_portlist) {
+			wildcard = 0;
+			if (!(inp->inp_vflag & INP_IPV6))
+				continue;
+			if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr))
+				wildcard++;
+			if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr)) {
+				if (IN6_IS_ADDR_UNSPECIFIED(laddr))
+					wildcard++;
+				else if (!IN6_ARE_ADDR_EQUAL(
+				    &inp->in6p_laddr, laddr))
 					continue;
-				if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr))
+			} else {
+				if (!IN6_IS_ADDR_UNSPECIFIED(laddr))
 					wildcard++;
-				if (!IN6_IS_ADDR_UNSPECIFIED(
-					&inp->in6p_laddr)) {
-					if (IN6_IS_ADDR_UNSPECIFIED(laddr))
-						wildcard++;
-					else if (!IN6_ARE_ADDR_EQUAL(
-						&inp->in6p_laddr, laddr))
-						continue;
-				} else {
-					if (!IN6_IS_ADDR_UNSPECIFIED(laddr))
-						wildcard++;
-				}
-				if (wildcard < matchwild) {
-					match = inp;
-					matchwild = wildcard;
-					if (matchwild == 0) {
-						break;
-					}
-				}
 			}
-		}
-		return (match);
-	}
-}
-#ifndef APPLE
-/* this is not used in Darwin */
-void
-in6_pcbpurgeif0(
-	struct in6pcb *head,
-	struct ifnet *ifp)
-{
-	struct in6pcb *in6p;
-	struct ip6_moptions *im6o;
-	struct in6_multi_mship *imm, *nimm;
-
-	for (in6p = head; in6p != NULL; in6p = LIST_NEXT(in6p, inp_list)) {
-		im6o = in6p->in6p_moptions;
-		if ((in6p->inp_vflag & INP_IPV6) &&
-		    im6o) {
-			/*
-			 * Unselect the outgoing interface if it is being
-			 * detached.
-			 */
-			if (im6o->im6o_multicast_ifp == ifp)
-				im6o->im6o_multicast_ifp = NULL;
-
-			/*
-			 * Drop multicast group membership if we joined
-			 * through the interface being detached.
-			 * XXX controversial - is it really legal for kernel
-			 * to force this?
-			 */
-			for (imm = im6o->im6o_memberships.lh_first;
-			     imm != NULL; imm = nimm) {
-				nimm = imm->i6mm_chain.le_next;
-				if (imm->i6mm_maddr->in6m_ifp == ifp) {
-					LIST_REMOVE(imm, i6mm_chain);
-					in6_delmulti(imm->i6mm_maddr);
-					FREE(imm, M_IPMADDR);
+			if (wildcard < matchwild) {
+				match = inp;
+				matchwild = wildcard;
+				if (matchwild == 0) {
+					break;
 				}
 			}
 		}
 	}
+	return (match);
 }
-#endif
 
 /*
  * Check for alternatives when higher level complains
@@ -1110,33 +1056,31 @@ in6_pcbpurgeif0(
  * (by a redirect), time to try a default gateway again.
  */
 void
-in6_losing(in6p)
-	struct inpcb *in6p;
+in6_losing(struct inpcb *in6p)
 {
 	struct rtentry *rt;
-	struct rt_addrinfo info;
 
 	if ((rt = in6p->in6p_route.ro_rt) != NULL) {
-		in6p->in6p_route.ro_rt = 0;
-		bzero((caddr_t)&info, sizeof(info));
-		info.rti_info[RTAX_DST] =
-			(struct sockaddr *)&in6p->in6p_route.ro_dst;
-		info.rti_info[RTAX_GATEWAY] = rt->rt_gateway;
-		info.rti_info[RTAX_NETMASK] = rt_mask(rt);
-		lck_mtx_lock(rt_mtx);
-		rt_missmsg(RTM_LOSING, &info, rt->rt_flags, 0);
-		if (rt->rt_flags & RTF_DYNAMIC)
-			(void)rtrequest_locked(RTM_DELETE, rt_key(rt),
-					rt->rt_gateway, rt_mask(rt), rt->rt_flags,
-					(struct rtentry **)0);
-		else
+		RT_LOCK(rt);
+		if (rt->rt_flags & RTF_DYNAMIC) {
+			/*
+			 * Prevent another thread from modifying rt_key,
+			 * rt_gateway via rt_setgate() after the rt_lock
+			 * is dropped by marking the route as defunct.
+			 */
+			rt->rt_flags |= RTF_CONDEMNED;
+			RT_UNLOCK(rt);
+			(void) rtrequest(RTM_DELETE, rt_key(rt),
+			    rt->rt_gateway, rt_mask(rt), rt->rt_flags, NULL);
+		} else {
+			RT_UNLOCK(rt);
+		}
 		/*
 		 * A new route can be allocated
 		 * the next time output is attempted.
 		 */
-			rtfree_locked(rt);
-		lck_mtx_unlock(rt_mtx);
 	}
+	ROUTE_RELEASE(&in6p->in6p_route);
 }
 
 /*
@@ -1144,105 +1088,194 @@ in6_losing(in6p)
  * and allocate a (hopefully) better one.
  */
 void
-in6_rtchange(
-	struct inpcb *inp,
-	int errno)
+in6_rtchange(struct inpcb *inp, int errno)
 {
-	if (inp->in6p_route.ro_rt) {
-		rtfree(inp->in6p_route.ro_rt);
-		inp->in6p_route.ro_rt = 0;
-		/*
-		 * A new route can be allocated the next time
-		 * output is attempted.
-		 */
+#pragma unused(errno)
+	/*
+	 * A new route can be allocated the next time
+	 * output is attempted.
+	 */
+	ROUTE_RELEASE(&inp->in6p_route);
+}
+
+/*
+ * Check if PCB exists hash list. Also returns uid and gid of socket
+ */
+int
+in6_pcblookup_hash_exists(struct inpcbinfo *pcbinfo, struct in6_addr *faddr,
+    u_int fport_arg, struct in6_addr *laddr, u_int lport_arg, int wildcard,
+    uid_t *uid, gid_t *gid, struct ifnet *ifp)
+{
+	struct inpcbhead *head;
+	struct inpcb *inp;
+	u_short fport = fport_arg, lport = lport_arg;
+	int found;
+
+	*uid = UID_MAX;
+	*gid = GID_MAX;
+
+	lck_rw_lock_shared(pcbinfo->ipi_lock);
+
+	/*
+	 * First look for an exact match.
+	 */
+	head = &pcbinfo->ipi_hashbase[INP_PCBHASH(faddr->s6_addr32[3] /* XXX */,
+	    lport, fport, pcbinfo->ipi_hashmask)];
+	LIST_FOREACH(inp, head, inp_hash) {
+		if (!(inp->inp_vflag & INP_IPV6))
+			continue;
+
+		if (inp_restricted_recv(inp, ifp))
+			continue;
+
+		if (IN6_ARE_ADDR_EQUAL(&inp->in6p_faddr, faddr) &&
+		    IN6_ARE_ADDR_EQUAL(&inp->in6p_laddr, laddr) &&
+		    inp->inp_fport == fport &&
+		    inp->inp_lport == lport) {
+			if ((found = (inp->inp_socket != NULL))) {
+				/*
+				 * Found. Check if pcb is still valid
+				 */
+				*uid = kauth_cred_getuid(
+				    inp->inp_socket->so_cred);
+				*gid = kauth_cred_getgid(
+				    inp->inp_socket->so_cred);
+			}
+			lck_rw_done(pcbinfo->ipi_lock);
+			return (found);
+		}
+	}
+	if (wildcard) {
+		struct inpcb *local_wild = NULL;
+
+		head = &pcbinfo->ipi_hashbase[INP_PCBHASH(INADDR_ANY, lport, 0,
+		    pcbinfo->ipi_hashmask)];
+		LIST_FOREACH(inp, head, inp_hash) {
+			if (!(inp->inp_vflag & INP_IPV6))
+				continue;
+
+			if (inp_restricted_recv(inp, ifp))
+				continue;
+
+			if (IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr) &&
+			    inp->inp_lport == lport) {
+				if (IN6_ARE_ADDR_EQUAL(&inp->in6p_laddr,
+				    laddr)) {
+					found = (inp->inp_socket != NULL);
+					if (found) {
+						*uid = kauth_cred_getuid(
+						    inp->inp_socket->so_cred);
+						*gid = kauth_cred_getgid(
+						    inp->inp_socket->so_cred);
+					}
+					lck_rw_done(pcbinfo->ipi_lock);
+					return (found);
+				} else if (IN6_IS_ADDR_UNSPECIFIED(
+				    &inp->in6p_laddr)) {
+					local_wild = inp;
+				}
+			}
+		}
+		if (local_wild) {
+			if ((found = (local_wild->inp_socket != NULL))) {
+				*uid = kauth_cred_getuid(
+				    local_wild->inp_socket->so_cred);
+				*gid = kauth_cred_getgid(
+				    local_wild->inp_socket->so_cred);
+			}
+			lck_rw_done(pcbinfo->ipi_lock);
+			return (found);
+		}
 	}
+
+	/*
+	 * Not found.
+	 */
+	lck_rw_done(pcbinfo->ipi_lock);
+	return (0);
 }
 
 /*
  * Lookup PCB in hash list.
  */
 struct inpcb *
-in6_pcblookup_hash(
-	struct inpcbinfo *pcbinfo,
-	struct in6_addr *faddr,
-	u_int fport_arg,
-	struct in6_addr *laddr,
-	u_int lport_arg,
-	int wildcard,
-	struct ifnet *ifp)
+in6_pcblookup_hash(struct inpcbinfo *pcbinfo, struct in6_addr *faddr,
+    u_int fport_arg, struct in6_addr *laddr, u_int lport_arg, int wildcard,
+    struct ifnet *ifp)
 {
 	struct inpcbhead *head;
 	struct inpcb *inp;
 	u_short fport = fport_arg, lport = lport_arg;
-	int faith;
-
-#if defined(NFAITH) && NFAITH > 0
-	faith = faithprefix(laddr);
-#else
-	faith = 0;
-#endif
 
-	lck_rw_lock_shared(pcbinfo->mtx);
+	lck_rw_lock_shared(pcbinfo->ipi_lock);
 
 	/*
 	 * First look for an exact match.
 	 */
-	head = &pcbinfo->hashbase[INP_PCBHASH(faddr->s6_addr32[3] /* XXX */,
-					      lport, fport,
-					      pcbinfo->hashmask)];
+	head = &pcbinfo->ipi_hashbase[INP_PCBHASH(faddr->s6_addr32[3] /* XXX */,
+	    lport, fport, pcbinfo->ipi_hashmask)];
 	LIST_FOREACH(inp, head, inp_hash) {
-		if ((inp->inp_vflag & INP_IPV6) == 0)
+		if (!(inp->inp_vflag & INP_IPV6))
+			continue;
+
+		if (inp_restricted_recv(inp, ifp))
 			continue;
+
 		if (IN6_ARE_ADDR_EQUAL(&inp->in6p_faddr, faddr) &&
 		    IN6_ARE_ADDR_EQUAL(&inp->in6p_laddr, laddr) &&
 		    inp->inp_fport == fport &&
 		    inp->inp_lport == lport) {
 			/*
-		 	* Found. Check if pcb is still valid
-		 	*/
-			if (in_pcb_checkstate(inp, WNT_ACQUIRE, 0) != WNT_STOPUSING) {
-				lck_rw_done(pcbinfo->mtx);
+			 * Found. Check if pcb is still valid
+			 */
+			if (in_pcb_checkstate(inp, WNT_ACQUIRE, 0) !=
+			    WNT_STOPUSING) {
+				lck_rw_done(pcbinfo->ipi_lock);
 				return (inp);
-			}
-			else {	/* it's there but dead, say it isn't found */
-				lck_rw_done(pcbinfo->mtx);	
-	    			return(NULL);
+			} else {
+				/* it's there but dead, say it isn't found */
+				lck_rw_done(pcbinfo->ipi_lock);
+				return (NULL);
 			}
 		}
 	}
 	if (wildcard) {
 		struct inpcb *local_wild = NULL;
 
-		head = &pcbinfo->hashbase[INP_PCBHASH(INADDR_ANY, lport, 0,
-						      pcbinfo->hashmask)];
+		head = &pcbinfo->ipi_hashbase[INP_PCBHASH(INADDR_ANY, lport, 0,
+		    pcbinfo->ipi_hashmask)];
 		LIST_FOREACH(inp, head, inp_hash) {
-			if ((inp->inp_vflag & INP_IPV6) == 0)
+			if (!(inp->inp_vflag & INP_IPV6))
+				continue;
+
+			if (inp_restricted_recv(inp, ifp))
 				continue;
+
 			if (IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr) &&
 			    inp->inp_lport == lport) {
-				if (faith && (inp->inp_flags & INP_FAITH) == 0)
-					continue;
 				if (IN6_ARE_ADDR_EQUAL(&inp->in6p_laddr,
-						       laddr)) {
-					if (in_pcb_checkstate(inp, WNT_ACQUIRE, 0) != WNT_STOPUSING) {
-						lck_rw_done(pcbinfo->mtx);
+				    laddr)) {
+					if (in_pcb_checkstate(inp, WNT_ACQUIRE,
+					    0) != WNT_STOPUSING) {
+						lck_rw_done(pcbinfo->ipi_lock);
 						return (inp);
+					} else {
+						/* dead; say it isn't found */
+						lck_rw_done(pcbinfo->ipi_lock);
+						return (NULL);
 					}
-					else {	/* it's there but dead, say it isn't found */
-						lck_rw_done(pcbinfo->mtx);	
-	    					return(NULL);
-					}
-				}
-				else if (IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr))
+				} else if (IN6_IS_ADDR_UNSPECIFIED(
+				    &inp->in6p_laddr)) {
 					local_wild = inp;
+				}
 			}
 		}
-		if (local_wild && in_pcb_checkstate(local_wild, WNT_ACQUIRE, 0) != WNT_STOPUSING) {
-			lck_rw_done(pcbinfo->mtx);
+		if (local_wild && in_pcb_checkstate(local_wild,
+		    WNT_ACQUIRE, 0) != WNT_STOPUSING) {
+			lck_rw_done(pcbinfo->ipi_lock);
 			return (local_wild);
-		}
-		else {
-			lck_rw_done(pcbinfo->mtx);
+		} else {
+			lck_rw_done(pcbinfo->ipi_lock);
 			return (NULL);
 		}
 	}
@@ -1250,7 +1283,7 @@ in6_pcblookup_hash(
 	/*
 	 * Not found.
 	 */
-	lck_rw_done(pcbinfo->mtx);
+	lck_rw_done(pcbinfo->ipi_lock);
 	return (NULL);
 }
 
@@ -1260,15 +1293,70 @@ init_sin6(struct sockaddr_in6 *sin6, struct mbuf *m)
 	struct ip6_hdr *ip;
 
 	ip = mtod(m, struct ip6_hdr *);
-	bzero(sin6, sizeof(*sin6));
-	sin6->sin6_len = sizeof(*sin6);
+	bzero(sin6, sizeof (*sin6));
+	sin6->sin6_len = sizeof (*sin6);
 	sin6->sin6_family = AF_INET6;
 	sin6->sin6_addr = ip->ip6_src;
-	if (IN6_IS_SCOPE_LINKLOCAL(&sin6->sin6_addr))
+	if (IN6_IS_SCOPE_LINKLOCAL(&sin6->sin6_addr)) {
 		sin6->sin6_addr.s6_addr16[1] = 0;
-	sin6->sin6_scope_id =
-		(m->m_pkthdr.rcvif && IN6_IS_SCOPE_LINKLOCAL(&sin6->sin6_addr))
-		? m->m_pkthdr.rcvif->if_index : 0;
+		if ((m->m_pkthdr.pkt_flags & (PKTF_LOOP|PKTF_IFAINFO)) ==
+		    (PKTF_LOOP|PKTF_IFAINFO))
+			sin6->sin6_scope_id = m->m_pkthdr.src_ifindex;
+		else if (m->m_pkthdr.rcvif != NULL)
+			sin6->sin6_scope_id = m->m_pkthdr.rcvif->if_index;
+	}
+}
+
+/*
+ * The following routines implement this scheme:
+ *
+ * Callers of ip6_output() that intend to cache the route in the inpcb pass
+ * a local copy of the struct route to ip6_output().  Using a local copy of
+ * the cached route significantly simplifies things as IP no longer has to
+ * worry about having exclusive access to the passed in struct route, since
+ * it's defined in the caller's stack; in essence, this allows for a lock-
+ * less operation when updating the struct route at the IP level and below,
+ * whenever necessary. The scheme works as follows:
+ *
+ * Prior to dropping the socket's lock and calling ip6_output(), the caller
+ * copies the struct route from the inpcb into its stack, and adds a reference
+ * to the cached route entry, if there was any.  The socket's lock is then
+ * dropped and ip6_output() is called with a pointer to the copy of struct
+ * route defined on the stack (not to the one in the inpcb.)
+ *
+ * Upon returning from ip6_output(), the caller then acquires the socket's
+ * lock and synchronizes the cache; if there is no route cached in the inpcb,
+ * it copies the local copy of struct route (which may or may not contain any
+ * route) back into the cache; otherwise, if the inpcb has a route cached in
+ * it, the one in the local copy will be freed, if there's any.  Trashing the
+ * cached route in the inpcb can be avoided because ip6_output() is single-
+ * threaded per-PCB (i.e. multiple transmits on a PCB are always serialized
+ * by the socket/transport layer.)
+ */
+void
+in6p_route_copyout(struct inpcb *inp, struct route_in6 *dst)
+{
+	struct route_in6 *src = &inp->in6p_route;
+
+	socket_lock_assert_owned(inp->inp_socket);
+
+	/* Minor sanity check */
+	if (src->ro_rt != NULL && rt_key(src->ro_rt)->sa_family != AF_INET6)
+		panic("%s: wrong or corrupted route: %p", __func__, src);
+
+	route_copyout((struct route *)dst, (struct route *)src, sizeof (*dst));
+}
+
+void
+in6p_route_copyin(struct inpcb *inp, struct route_in6 *src)
+{
+	struct route_in6 *dst = &inp->in6p_route;
+
+	socket_lock_assert_owned(inp->inp_socket);
+
+	/* Minor sanity check */
+	if (src->ro_rt != NULL && rt_key(src->ro_rt)->sa_family != AF_INET6)
+		panic("%s: wrong or corrupted route: %p", __func__, src);
 
-	return;
+	route_copyin((struct route *)src, (struct route *)dst, sizeof (*src));
 }