]> git.saurik.com Git - apple/xnu.git/blobdiff - bsd/netinet/ip_input.c
xnu-1699.22.81.tar.gz
[apple/xnu.git] / bsd / netinet / ip_input.c
index ce9949bdd870304242e21957d9c64ca1f745ed59..761b4b40c303d74f56ca4bfa58019ab6b794d0c1 100644 (file)
@@ -1,23 +1,29 @@
 /*
- * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
+ * Copyright (c) 2000-2011 Apple Inc. All rights reserved.
  *
- * @APPLE_LICENSE_HEADER_START@
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
  * 
- * The contents of this file constitute Original Code as defined in and
- * are subject to the Apple Public Source License Version 1.1 (the
- * "License").  You may not use this file except in compliance with the
- * License.  Please obtain a copy of the License at
- * http://www.apple.com/publicsource 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.
  * 
- * This Original Code and all software distributed under the License are
- * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
+ * 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 OR NON-INFRINGEMENT.  Please see the
- * License for the specific language governing rights and limitations
- * under the License.
+ * 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_HEADER_END@
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  */
 /*
  * Copyright (c) 1982, 1986, 1988, 1993
  *     @(#)ip_input.c  8.2 (Berkeley) 1/4/94
  * $FreeBSD: src/sys/netinet/ip_input.c,v 1.130.2.25 2001/08/29 21:41:37 jesper Exp $
  */
+/*
+ * NOTICE: This file was modified by SPARTA, Inc. in 2007 to introduce
+ * support for mandatory and extensible security protections.  This notice
+ * is included in support of clause 2.2 (b) of the Apple Public License,
+ * Version 2.0.
+ */
 
 #define        _IP_VHL
 
 #include <sys/kernel.h>
 #include <sys/syslog.h>
 #include <sys/sysctl.h>
+#include <sys/mcache.h>
+#include <mach/mach_time.h>
+
+#include <machine/endian.h>
 
 #include <kern/queue.h>
+#include <kern/locks.h>
+
+#include <pexpert/pexpert.h>
 
 #include <net/if.h>
 #include <net/if_var.h>
 #include <net/if_dl.h>
 #include <net/route.h>
-#include <net/netisr.h>
+#include <net/kpi_protocol.h>
+#include <net/ntstat.h>
 
 #include <netinet/in.h>
 #include <netinet/in_systm.h>
 #include <netinet/in_var.h>
+#include <netinet/in_arp.h>
 #include <netinet/ip.h>
 #include <netinet/in_pcb.h>
 #include <netinet/ip_var.h>
 #include <sys/socketvar.h>
 
 #include <netinet/ip_fw.h>
+#include <netinet/ip_divert.h>
+
+#include <netinet/kpi_ipfilter_var.h>
 
 /* needed for AUTOCONFIGURING: */
 #include <netinet/udp.h>
 #include <netinet/udp_var.h>
 #include <netinet/bootp.h>
+#include <mach/sdt.h>
+
+#if CONFIG_MACF_NET
+#include <security/mac_framework.h>
+#endif
 
 #include <sys/kdebug.h>
+#include <libkern/OSAtomic.h>
 
 #define DBG_LAYER_BEG          NETDBG_CODE(DBG_NETIP, 0)
 #define DBG_LAYER_END          NETDBG_CODE(DBG_NETIP, 2)
 #include <netinet/ip_dummynet.h>
 #endif
 
+#if PF
+#include <net/pfvar.h>
+#endif /* PF */
+
 #if IPSEC
 extern int ipsec_bypass;
+extern lck_mtx_t *sadb_mutex;
+
+lck_grp_t         *sadb_stat_mutex_grp;
+lck_grp_attr_t    *sadb_stat_mutex_grp_attr;
+lck_attr_t        *sadb_stat_mutex_attr;
+lck_mtx_t         *sadb_stat_mutex;
+
 #endif
 
 int rsvp_on = 0;
 static int ip_rsvp_on;
 struct socket *ip_rsvpd;
 
+static int sysctl_ipforwarding SYSCTL_HANDLER_ARGS;
+
 int    ipforwarding = 0;
-SYSCTL_INT(_net_inet_ip, IPCTL_FORWARDING, forwarding, CTLFLAG_RW,
-    &ipforwarding, 0, "Enable IP forwarding between interfaces");
+SYSCTL_PROC(_net_inet_ip, IPCTL_FORWARDING, forwarding,
+    CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_LOCKED, &ipforwarding, 0,
+    sysctl_ipforwarding, "I", "Enable IP forwarding between interfaces");
 
 static int     ipsendredirects = 1; /* XXX */
-SYSCTL_INT(_net_inet_ip, IPCTL_SENDREDIRECTS, redirect, CTLFLAG_RW,
+SYSCTL_INT(_net_inet_ip, IPCTL_SENDREDIRECTS, redirect, CTLFLAG_RW | CTLFLAG_LOCKED,
     &ipsendredirects, 0, "Enable sending IP redirects");
 
 int    ip_defttl = IPDEFTTL;
-SYSCTL_INT(_net_inet_ip, IPCTL_DEFTTL, ttl, CTLFLAG_RW,
+SYSCTL_INT(_net_inet_ip, IPCTL_DEFTTL, ttl, CTLFLAG_RW | CTLFLAG_LOCKED,
     &ip_defttl, 0, "Maximum TTL on IP packets");
 
 static int     ip_dosourceroute = 0;
-SYSCTL_INT(_net_inet_ip, IPCTL_SOURCEROUTE, sourceroute, CTLFLAG_RW,
+SYSCTL_INT(_net_inet_ip, IPCTL_SOURCEROUTE, sourceroute, CTLFLAG_RW | CTLFLAG_LOCKED,
     &ip_dosourceroute, 0, "Enable forwarding source routed IP packets");
 
 static int     ip_acceptsourceroute = 0;
 SYSCTL_INT(_net_inet_ip, IPCTL_ACCEPTSOURCEROUTE, accept_sourceroute, 
-    CTLFLAG_RW, &ip_acceptsourceroute, 0, 
+    CTLFLAG_RW | CTLFLAG_LOCKED, &ip_acceptsourceroute, 0, 
     "Enable accepting source routed IP packets");
 
 static int     ip_keepfaith = 0;
-SYSCTL_INT(_net_inet_ip, IPCTL_KEEPFAITH, keepfaith, CTLFLAG_RW,
+SYSCTL_INT(_net_inet_ip, IPCTL_KEEPFAITH, keepfaith, CTLFLAG_RW | CTLFLAG_LOCKED,
        &ip_keepfaith,  0,
        "Enable packet capture for FAITH IPv4->IPv6 translater daemon");
 
-static int     ip_nfragpackets = 0;
-static int     ip_maxfragpackets;      /* initialized in ip_init() */
-SYSCTL_INT(_net_inet_ip, OID_AUTO, maxfragpackets, CTLFLAG_RW,
-       &ip_maxfragpackets, 0,
+static int     nipq = 0;       /* total # of reass queues */
+static int     maxnipq;
+SYSCTL_INT(_net_inet_ip, OID_AUTO, maxfragpackets, CTLFLAG_RW | CTLFLAG_LOCKED,
+       &maxnipq, 0,
        "Maximum number of IPv4 fragment reassembly queue entries");
 
+static int    maxfragsperpacket;
+SYSCTL_INT(_net_inet_ip, OID_AUTO, maxfragsperpacket, CTLFLAG_RW | CTLFLAG_LOCKED,
+       &maxfragsperpacket, 0,
+       "Maximum number of IPv4 fragments allowed per packet");
+
+static int    maxfrags;
+SYSCTL_INT(_net_inet_ip, OID_AUTO, maxfrags, CTLFLAG_RW | CTLFLAG_LOCKED,
+       &maxfrags, 0, "Maximum number of IPv4 fragments allowed");
+
+static int    currentfrags = 0;
+
+int    ip_doscopedroute = 1;
+SYSCTL_INT(_net_inet_ip, OID_AUTO, scopedroute, CTLFLAG_RD | CTLFLAG_LOCKED,
+     &ip_doscopedroute, 0, "Enable IPv4 scoped routing");
+
 /*
  * XXX - Setting ip_checkinterface mostly implements the receive side of
  * the Strong ES model described in RFC 1122, but since the routing table
@@ -168,26 +227,41 @@ SYSCTL_INT(_net_inet_ip, OID_AUTO, maxfragpackets, CTLFLAG_RW,
  * packets for those addresses are received.
  */
 static int     ip_checkinterface = 0;
-SYSCTL_INT(_net_inet_ip, OID_AUTO, check_interface, CTLFLAG_RW,
+SYSCTL_INT(_net_inet_ip, OID_AUTO, check_interface, CTLFLAG_RW | CTLFLAG_LOCKED,
     &ip_checkinterface, 0, "Verify packet arrives on correct interface");
 
+
 #if DIAGNOSTIC
 static int     ipprintfs = 0;
 #endif
 
+extern int in_proto_count; 
 extern struct domain inetdomain;
 extern struct protosw inetsw[];
 struct protosw *ip_protox[IPPROTO_MAX];
 static int     ipqmaxlen = IFQ_MAXLEN;
-struct in_ifaddrhead in_ifaddrhead; /* first inet address */
+
+static lck_grp_attr_t  *in_ifaddr_rwlock_grp_attr;
+static lck_grp_t       *in_ifaddr_rwlock_grp;
+static lck_attr_t      *in_ifaddr_rwlock_attr;
+lck_rw_t               *in_ifaddr_rwlock;
+
+/* Protected by in_ifaddr_rwlock */
+struct in_ifaddrhead in_ifaddrhead;            /* first inet address */
+struct in_ifaddrhashhead *in_ifaddrhashtbl;    /* inet addr hash table  */
+
+#define        INADDR_NHASH    61
+static u_int32_t inaddr_nhash;                 /* hash table size */
+static u_int32_t inaddr_hashp;                 /* next largest prime */
+
 struct ifqueue ipintrq;
-SYSCTL_INT(_net_inet_ip, IPCTL_INTRQMAXLEN, intr_queue_maxlen, CTLFLAG_RW,
+SYSCTL_INT(_net_inet_ip, IPCTL_INTRQMAXLEN, intr_queue_maxlen, CTLFLAG_RW | CTLFLAG_LOCKED,
     &ipintrq.ifq_maxlen, 0, "Maximum size of the IP input queue");
-SYSCTL_INT(_net_inet_ip, IPCTL_INTRQDROPS, intr_queue_drops, CTLFLAG_RD,
+SYSCTL_INT(_net_inet_ip, IPCTL_INTRQDROPS, intr_queue_drops, CTLFLAG_RD | CTLFLAG_LOCKED,
     &ipintrq.ifq_drops, 0, "Number of packets dropped from the IP input queue");
 
 struct ipstat ipstat;
-SYSCTL_STRUCT(_net_inet_ip, IPCTL_STATS, stats, CTLFLAG_RD,
+SYSCTL_STRUCT(_net_inet_ip, IPCTL_STATS, stats, CTLFLAG_RD | CTLFLAG_LOCKED,
     &ipstat, ipstat, "IP statistics (struct ipstat, netinet/ip_var.h)");
 
 /* Packet reassembly stuff */
@@ -198,44 +272,53 @@ SYSCTL_STRUCT(_net_inet_ip, IPCTL_STATS, stats, CTLFLAG_RD,
        (((((x) & 0xF) | ((((x) >> 8) & 0xF) << 4)) ^ (y)) & IPREASS_HMASK)
 
 static struct ipq ipq[IPREASS_NHASH];
-static int    nipq = 0;         /* total # of reass queues */
-static int    maxnipq;
+static TAILQ_HEAD(ipq_list, ipq) ipq_list =
+       TAILQ_HEAD_INITIALIZER(ipq_list);
 const  int    ipintrq_present = 1;
+lck_mtx_t              *ip_mutex;
+lck_attr_t             *ip_mutex_attr;
+lck_grp_t              *ip_mutex_grp;
+lck_grp_attr_t         *ip_mutex_grp_attr;
+lck_mtx_t              *inet_domain_mutex;
+extern lck_mtx_t       *domain_proto_mtx;
 
 #if IPCTL_DEFMTU
-SYSCTL_INT(_net_inet_ip, IPCTL_DEFMTU, mtu, CTLFLAG_RW,
+SYSCTL_INT(_net_inet_ip, IPCTL_DEFMTU, mtu, CTLFLAG_RW | CTLFLAG_LOCKED,
     &ip_mtu, 0, "Default MTU");
 #endif
 
 #if IPSTEALTH
 static int     ipstealth = 0;
-SYSCTL_INT(_net_inet_ip, OID_AUTO, stealth, CTLFLAG_RW,
+SYSCTL_INT(_net_inet_ip, OID_AUTO, stealth, CTLFLAG_RW | CTLFLAG_LOCKED,
     &ipstealth, 0, "");
 #endif
 
 
 /* Firewall hooks */
+#if IPFIREWALL
 ip_fw_chk_t *ip_fw_chk_ptr;
-ip_fw_ctl_t *ip_fw_ctl_ptr;
-int fw_enable = 1 ;
+int fw_enable = 1;
+int fw_bypass = 1;
+int fw_one_pass = 0;
 
 #if DUMMYNET
-ip_dn_ctl_t *ip_dn_ctl_ptr;
+ip_dn_io_t *ip_dn_io_ptr;
 #endif
 
-int (*fr_checkp) __P((struct ip *, int, struct ifnet *, int, struct mbuf **)) = NULL;
+int (*fr_checkp)(struct ip *, int, struct ifnet *, int, struct mbuf **) = NULL;
+#endif /* IPFIREWALL */
 
-SYSCTL_NODE(_net_inet_ip, OID_AUTO, linklocal, CTLFLAG_RW, 0, "link local");
+SYSCTL_NODE(_net_inet_ip, OID_AUTO, linklocal, CTLFLAG_RW | CTLFLAG_LOCKED, 0, "link local");
 
 struct ip_linklocal_stat ip_linklocal_stat;
-SYSCTL_STRUCT(_net_inet_ip_linklocal, OID_AUTO, stat, CTLFLAG_RD,
+SYSCTL_STRUCT(_net_inet_ip_linklocal, OID_AUTO, stat, CTLFLAG_RD | CTLFLAG_LOCKED,
         &ip_linklocal_stat, ip_linklocal_stat,
         "Number of link local packets with TTL less than 255");
 
-SYSCTL_NODE(_net_inet_ip_linklocal, OID_AUTO, in, CTLFLAG_RW, 0, "link local input");
+SYSCTL_NODE(_net_inet_ip_linklocal, OID_AUTO, in, CTLFLAG_RW | CTLFLAG_LOCKED, 0, "link local input");
 
-int ip_linklocal_in_allowbadttl = 0;
-SYSCTL_INT(_net_inet_ip_linklocal_in, OID_AUTO, allowbadttl, CTLFLAG_RW,
+int ip_linklocal_in_allowbadttl = 1;
+SYSCTL_INT(_net_inet_ip_linklocal_in, OID_AUTO, allowbadttl, CTLFLAG_RW | CTLFLAG_LOCKED,
         &ip_linklocal_in_allowbadttl, 0,
         "Allow incoming link local packets with TTL less than 255");
 
@@ -255,55 +338,76 @@ static    struct ip_srcrt {
        struct  in_addr route[MAX_IPOPTLEN/sizeof(struct in_addr)];
 } ip_srcrt;
 
-struct sockaddr_in *ip_fw_fwd_addr;
-
-#ifdef __APPLE__
-extern struct mbuf*    m_dup(register struct mbuf *m, int how);
-#endif
-
-static void    save_rte __P((u_char *, struct in_addr));
-static int     ip_dooptions __P((struct mbuf *));
-static void    ip_forward __P((struct mbuf *, int));
-static void    ip_freef __P((struct ipq *));
+static void    in_ifaddrhashtbl_init(void);
+static void    save_rte(u_char *, struct in_addr);
+static int     ip_dooptions(struct mbuf *, int, struct sockaddr_in *);
+static void    ip_forward(struct mbuf *, int, struct sockaddr_in *);
+static void    ip_freef(struct ipq *);
 #if IPDIVERT
 #ifdef IPDIVERT_44
-static struct  mbuf *ip_reass __P((struct mbuf *,
-                       struct ipq *, struct ipq *, u_int32_t *, u_int16_t *));
+static struct  mbuf *ip_reass(struct mbuf *,
+                       struct ipq *, struct ipq *, u_int32_t *, u_int16_t *);
 #else
-static struct  mbuf *ip_reass __P((struct mbuf *,
-                       struct ipq *, struct ipq *, u_int16_t *, u_int16_t *));
+static struct  mbuf *ip_reass(struct mbuf *,
+                       struct ipq *, struct ipq *, u_int16_t *, u_int16_t *);
 #endif
 #else
-static struct  mbuf *ip_reass __P((struct mbuf *, struct ipq *, struct ipq *));
+static struct  mbuf *ip_reass(struct mbuf *, struct ipq *, struct ipq *);
 #endif
-static struct  in_ifaddr *ip_rtaddr __P((struct in_addr));
-void   ipintr __P((void));
+static void ip_fwd_route_copyout(struct ifnet *, struct route *);
+static void ip_fwd_route_copyin(struct ifnet *, struct route *);
+void   ipintr(void);
+void   in_dinit(void);
 
 #if RANDOM_IP_ID
 extern u_short ip_id;
+
+int    ip_use_randomid = 1;
+SYSCTL_INT(_net_inet_ip, OID_AUTO, random_id, CTLFLAG_RW | CTLFLAG_LOCKED,
+    &ip_use_randomid, 0, "Randomize IP packets IDs");
 #endif
 
+#define        satosin(sa)     ((struct sockaddr_in *)(sa))
+#define        ifatoia(ifa)    ((struct in_ifaddr *)(ifa))
+
 /*
  * IP initialization: fill in IP protocol switch table.
  * All protocols not implemented in kernel go to raw IP protocol handler.
  */
 void
-ip_init()
+ip_init(void)
 {
-       register struct protosw *pr;
-       register int i;
-       static ip_initialized = 0;
+       struct protosw *pr;
+       int i;
+       static int ip_initialized = 0;
 
        if (!ip_initialized)
        {
+               PE_parse_boot_argn("net.inet.ip.scopedroute",
+                   &ip_doscopedroute, sizeof (ip_doscopedroute));
+
+               in_ifaddr_init();
+
+               in_ifaddr_rwlock_grp_attr = lck_grp_attr_alloc_init();
+               in_ifaddr_rwlock_grp = lck_grp_alloc_init("in_ifaddr_rwlock",
+                   in_ifaddr_rwlock_grp_attr);
+               in_ifaddr_rwlock_attr = lck_attr_alloc_init();
+               in_ifaddr_rwlock = lck_rw_alloc_init(in_ifaddr_rwlock_grp,
+                   in_ifaddr_rwlock_attr);
+
                TAILQ_INIT(&in_ifaddrhead);
-               pr = pffindproto(PF_INET, IPPROTO_RAW, SOCK_RAW);
+               in_ifaddrhashtbl_init();
+
+               ip_moptions_init();
+
+               pr = pffindproto_locked(PF_INET, IPPROTO_RAW, SOCK_RAW);
                if (pr == 0)
                        panic("ip_init");
                for (i = 0; i < IPPROTO_MAX; i++)
                        ip_protox[i] = pr;
-               for (pr = inetdomain.dom_protosw; pr; pr = pr->pr_next)
-               {       if(!((unsigned int)pr->pr_domain)) continue;    /* If uninitialized, skip */
+               for (pr = inetdomain.dom_protosw; pr; pr = pr->pr_next) {
+                       if (pr->pr_domain == NULL)
+                               continue;    /* If uninitialized, skip */
                        if (pr->pr_domain->dom_family == PF_INET &&
                            pr->pr_protocol && pr->pr_protocol != IPPROTO_RAW)
                                ip_protox[pr->pr_protocol] = pr;
@@ -311,39 +415,213 @@ ip_init()
                for (i = 0; i < IPREASS_NHASH; i++)
                    ipq[i].next = ipq[i].prev = &ipq[i];
 
-               maxnipq = nmbclusters / 4;
-               ip_maxfragpackets = nmbclusters / 4;
+       maxnipq = nmbclusters / 32;
+       maxfrags = maxnipq * 2;
+       maxfragsperpacket = 128; /* enough for 64k in 512 byte fragments */
 
 #if RANDOM_IP_ID
-               ip_id = time_second & 0xffff;
+               {
+                       struct timeval timenow;
+                       getmicrotime(&timenow);
+                       ip_id = timenow.tv_sec & 0xffff;
+               }
 #endif
                ipintrq.ifq_maxlen = ipqmaxlen;
+
+               ipf_init();
+
+               ip_mutex_grp_attr  = lck_grp_attr_alloc_init();
+
+               ip_mutex_grp = lck_grp_alloc_init("ip", ip_mutex_grp_attr);
+
+               ip_mutex_attr = lck_attr_alloc_init();
+
+               if ((ip_mutex = lck_mtx_alloc_init(ip_mutex_grp, ip_mutex_attr)) == NULL) {
+                       printf("ip_init: can't alloc ip_mutex\n");
+                       return;
+               }
+
+#if IPSEC
+       
+               sadb_stat_mutex_grp_attr = lck_grp_attr_alloc_init();
+               sadb_stat_mutex_grp = lck_grp_alloc_init("sadb_stat", sadb_stat_mutex_grp_attr);
+               sadb_stat_mutex_attr = lck_attr_alloc_init();
+
+               if ((sadb_stat_mutex = lck_mtx_alloc_init(sadb_stat_mutex_grp, sadb_stat_mutex_attr)) == NULL) {
+                       printf("ip_init: can't alloc sadb_stat_mutex\n");
+                       return;
+               }
+
+#endif
+               arp_init();
+
                ip_initialized = 1;
        }
 }
 
+/*
+ * Initialize IPv4 source address hash table.
+ */
+static void
+in_ifaddrhashtbl_init(void)
+{
+       int i, k, p;
+
+       if (in_ifaddrhashtbl != NULL)
+               return;
+
+       PE_parse_boot_argn("inaddr_nhash", &inaddr_nhash, sizeof (inaddr_nhash));
+       if (inaddr_nhash == 0)
+               inaddr_nhash = INADDR_NHASH;
+
+       MALLOC(in_ifaddrhashtbl, struct in_ifaddrhashhead *,
+           inaddr_nhash * sizeof (*in_ifaddrhashtbl),
+           M_IFADDR, M_WAITOK | M_ZERO);
+       if (in_ifaddrhashtbl == NULL)
+               panic("in_ifaddrhashtbl_init allocation failed");
+
+       /*
+        * Generate the next largest prime greater than inaddr_nhash.
+        */
+       k = (inaddr_nhash % 2 == 0) ? inaddr_nhash + 1 : inaddr_nhash + 2;
+       for (;;) {
+               p = 1;
+               for (i = 3; i * i <= k; i += 2) {
+                       if (k % i == 0)
+                               p = 0;
+               }
+               if (p == 1)
+                       break;
+               k += 2;
+       }
+       inaddr_hashp = k;
+}
+
+u_int32_t
+inaddr_hashval(u_int32_t key)
+{
+       /*
+        * The hash index is the computed prime times the key modulo
+        * the hash size, as documented in "Introduction to Algorithms"
+        * (Cormen, Leiserson, Rivest).
+        */
+       if (inaddr_nhash > 1)
+               return ((key * inaddr_hashp) % inaddr_nhash);
+       else
+               return (0);
+}
+
+static void
+ip_proto_input(
+       protocol_family_t       __unused protocol,
+       mbuf_t                          packet_list)
+{
+       mbuf_t  packet;
+       int how_many = 0 ;
+       
+       /* ip_input should handle a list of packets but does not yet */
+       
+       for (packet = packet_list; packet; packet = packet_list) {
+               how_many++;
+               packet_list = mbuf_nextpkt(packet);
+               mbuf_setnextpkt(packet, NULL);
+               ip_input(packet);
+       }
+}
+
 /* Initialize the PF_INET domain, and add in the pre-defined protos */
 void
-in_dinit()
-{      register int i;
-       register struct protosw *pr;
-       register struct domain *dp;
-       static inetdomain_initted = 0;
-       extern int in_proto_count; 
+in_dinit(void)
+{
+       int i;
+       struct protosw *pr;
+       struct domain *dp;
+       static int inetdomain_initted = 0;
 
        if (!inetdomain_initted)
        {
-               kprintf("Initing %d protosw entries\n", in_proto_count);
+               /* kprintf("Initing %d protosw entries\n", in_proto_count); */
                dp = &inetdomain;
+               dp->dom_flags = DOM_REENTRANT;
 
                for (i=0, pr = &inetsw[0]; i<in_proto_count; i++, pr++)
                        net_add_proto(pr, dp);
+               inet_domain_mutex = dp->dom_mtx;
                inetdomain_initted = 1;
+       
+               lck_mtx_unlock(domain_proto_mtx);       
+               proto_register_input(PF_INET, ip_proto_input, NULL, 1);
+               lck_mtx_lock(domain_proto_mtx); 
        }
 }
 
-static struct  sockaddr_in ipaddr = { sizeof(ipaddr), AF_INET };
-static struct  route ipforward_rt;
+__private_extern__ void
+ip_proto_dispatch_in(
+                                       struct mbuf     *m,
+                                       int                     hlen,
+                                       u_int8_t        proto,
+                                       ipfilter_t      inject_ipfref)
+{
+       struct ipfilter *filter;
+       int seen = (inject_ipfref == 0);
+       int     changed_header = 0;
+       struct ip *ip;
+       void (*pr_input)(struct mbuf *, int len);
+
+       if (!TAILQ_EMPTY(&ipv4_filters)) {      
+               ipf_ref();
+               TAILQ_FOREACH(filter, &ipv4_filters, ipf_link) {
+                       if (seen == 0) {
+                               if ((struct ipfilter *)inject_ipfref == filter)
+                                       seen = 1;
+                       } else if (filter->ipf_filter.ipf_input) {
+                               errno_t result;
+               
+                               if (changed_header == 0) {
+                                       changed_header = 1;
+                                       ip = mtod(m, struct ip *);
+                                       ip->ip_len = htons(ip->ip_len + hlen);
+                                       ip->ip_off = htons(ip->ip_off);
+                                       ip->ip_sum = 0;
+                                       ip->ip_sum = in_cksum(m, hlen);
+                               }
+                               result = filter->ipf_filter.ipf_input(
+                                       filter->ipf_filter.cookie, (mbuf_t*)&m, hlen, proto);
+                               if (result == EJUSTRETURN) {
+                                       ipf_unref();
+                                       return;
+                               }
+                               if (result != 0) {
+                                       ipf_unref();
+                                       m_freem(m);
+                                       return;
+                               }
+       }
+               }
+               ipf_unref();
+       }
+       /*
+        * If there isn't a specific lock for the protocol
+        * we're about to call, use the generic lock for AF_INET.
+        * otherwise let the protocol deal with its own locking
+        */
+       ip = mtod(m, struct ip *);
+
+       if (changed_header) {
+               ip->ip_len = ntohs(ip->ip_len) - hlen;
+               ip->ip_off = ntohs(ip->ip_off);
+       }
+
+       if ((pr_input = ip_protox[ip->ip_p]->pr_input) == NULL) {
+               m_freem(m);
+       } else if (!(ip_protox[ip->ip_p]->pr_flags & PR_PROTOLOCK)) {
+               lck_mtx_lock(inet_domain_mutex);
+               pr_input(m, hlen);
+               lck_mtx_unlock(inet_domain_mutex);
+       } else {
+               pr_input(m, hlen);
+       }
+}
 
 /*
  * Ip input routine.  Checksum and byte swap header.  If fragmented
@@ -355,51 +633,109 @@ ip_input(struct mbuf *m)
        struct ip *ip;
        struct ipq *fp;
        struct in_ifaddr *ia = NULL;
-       int    i, hlen, mff, checkif;
+       int    hlen, checkif;
        u_short sum;
-       u_int16_t divert_cookie;                /* firewall cookie */
        struct in_addr pkt_dst;
-#if IPDIVERT
-       u_int32_t divert_info = 0;              /* packet divert/tee info */
+#if IPFIREWALL
+       int i;
+       u_int32_t div_info = 0;         /* packet divert/tee info */
+       struct ip_fw_args args;
+       struct m_tag    *tag;
 #endif
-       struct ip_fw_chain *rule = NULL;
+       ipfilter_t inject_filter_ref = 0;
+
+       /* Check if the mbuf is still valid after interface filter processing */
+       MBUF_INPUT_CHECK(m, m->m_pkthdr.rcvif);
+
+#if IPFIREWALL
+       args.eh = NULL;
+       args.oif = NULL;
+       args.rule = NULL;
+       args.divert_rule = 0;                   /* divert cookie */
+       args.next_hop = NULL;
+
+       /*
+        * Don't bother searching for tag(s) if there's none.
+        */
+       if (SLIST_EMPTY(&m->m_pkthdr.tags))
+               goto ipfw_tags_done;
+
+       /* Grab info from mtags prepended to the chain */
+#if DUMMYNET
+       if ((tag = m_tag_locate(m, KERNEL_MODULE_TAG_ID,
+           KERNEL_TAG_TYPE_DUMMYNET, NULL)) != NULL) {
+               struct dn_pkt_tag       *dn_tag;
+
+               dn_tag = (struct dn_pkt_tag *)(tag+1);
+               args.rule = dn_tag->rule;
+
+               m_tag_delete(m, tag);
+       }
+#endif /* DUMMYNET */
 
 #if IPDIVERT
-       /* Get and reset firewall cookie */
-       divert_cookie = ip_divert_cookie;
-       ip_divert_cookie = 0;
-#else
-       divert_cookie = 0;
-#endif
+       if ((tag = m_tag_locate(m, KERNEL_MODULE_TAG_ID,
+           KERNEL_TAG_TYPE_DIVERT, NULL)) != NULL) {
+               struct divert_tag       *div_tag;
 
-#if IPFIREWALL && DUMMYNET
-        /*
-         * dummynet packet are prepended a vestigial mbuf with
-         * m_type = MT_DUMMYNET and m_data pointing to the matching
-         * rule.
-         */
-        if (m->m_type == MT_DUMMYNET) {
-            rule = (struct ip_fw_chain *)(m->m_data) ;
-            m = m->m_next ;
-            ip = mtod(m, struct ip *);
-            hlen = IP_VHL_HL(ip->ip_vhl) << 2;
-            goto iphack ;
-        } else
-            rule = NULL ;
+               div_tag = (struct divert_tag *)(tag+1);
+               args.divert_rule = div_tag->cookie;
+
+               m_tag_delete(m, tag);
+       }
 #endif
 
+       if ((tag = m_tag_locate(m, KERNEL_MODULE_TAG_ID,
+           KERNEL_TAG_TYPE_IPFORWARD, NULL)) != NULL) {
+               struct ip_fwd_tag       *ipfwd_tag;
+
+               ipfwd_tag = (struct ip_fwd_tag *)(tag+1);
+               args.next_hop = ipfwd_tag->next_hop;
+
+               m_tag_delete(m, tag);
+       }
+
 #if    DIAGNOSTIC
        if (m == NULL || (m->m_flags & M_PKTHDR) == 0)
                panic("ip_input no HDR");
 #endif
-       ipstat.ips_total++;
+
+       if (args.rule) {        /* dummynet already filtered us */
+               ip = mtod(m, struct ip *);
+               hlen = IP_VHL_HL(ip->ip_vhl) << 2;
+               inject_filter_ref = ipf_get_inject_filter(m);
+               goto iphack ;
+       }
+ipfw_tags_done:
+#endif /* IPFIREWALL */
+
+       /*
+        * No need to proccess packet twice if we've already seen it.
+        */
+       if (!SLIST_EMPTY(&m->m_pkthdr.tags))
+               inject_filter_ref = ipf_get_inject_filter(m);
+       if (inject_filter_ref != 0) {
+               ip = mtod(m, struct ip *);
+               hlen = IP_VHL_HL(ip->ip_vhl) << 2;
+
+               DTRACE_IP6(receive, struct mbuf *, m, struct inpcb *, NULL, 
+                       struct ip *, ip, struct ifnet *, m->m_pkthdr.rcvif,
+                       struct ip *, ip, struct ip6_hdr *, NULL);
+               
+               ip->ip_len = ntohs(ip->ip_len) - hlen;
+               ip->ip_off = ntohs(ip->ip_off);
+               ip_proto_dispatch_in(m, hlen, ip->ip_p, inject_filter_ref);
+               return;
+       }
+
+       OSAddAtomic(1, &ipstat.ips_total);
 
        if (m->m_pkthdr.len < sizeof(struct ip))
                goto tooshort;
 
        if (m->m_len < sizeof (struct ip) &&
            (m = m_pullup(m, sizeof (struct ip))) == 0) {
-               ipstat.ips_toosmall++;
+               OSAddAtomic(1, &ipstat.ips_toosmall);
                return;
        }
        ip = mtod(m, struct ip *);
@@ -408,18 +744,18 @@ ip_input(struct mbuf *m)
                     ip->ip_src.s_addr, ip->ip_p, ip->ip_off, ip->ip_len);
 
        if (IP_VHL_V(ip->ip_vhl) != IPVERSION) {
-               ipstat.ips_badvers++;
+               OSAddAtomic(1, &ipstat.ips_badvers);
                goto bad;
        }
 
        hlen = IP_VHL_HL(ip->ip_vhl) << 2;
        if (hlen < sizeof(struct ip)) { /* minimum header length */
-               ipstat.ips_badhlen++;
+               OSAddAtomic(1, &ipstat.ips_badhlen);
                goto bad;
        }
        if (hlen > m->m_len) {
                if ((m = m_pullup(m, hlen)) == 0) {
-                       ipstat.ips_badhlen++;
+                       OSAddAtomic(1, &ipstat.ips_badhlen);
                        return;
                }
                ip = mtod(m, struct ip *);
@@ -429,9 +765,7 @@ ip_input(struct mbuf *m)
        if ((ntohl(ip->ip_dst.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET ||
            (ntohl(ip->ip_src.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET) {
                if ((m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) == 0) {
-#ifndef __APPLE__
-                       ipstat.ips_badaddr++;
-#endif
+                       OSAddAtomic(1, &ipstat.ips_badaddr);
                        goto bad;
                }
        }
@@ -441,38 +775,86 @@ ip_input(struct mbuf *m)
            IN_LINKLOCAL(ntohl(ip->ip_src.s_addr)))) {
                ip_linklocal_stat.iplls_in_total++;
                if (ip->ip_ttl != MAXTTL) {
-                       ip_linklocal_stat.iplls_in_badttl++;
+                       OSAddAtomic(1, &ip_linklocal_stat.iplls_in_badttl);
                        /* Silently drop link local traffic with bad TTL */
-                       if (ip_linklocal_in_allowbadttl != 0)
+                       if (!ip_linklocal_in_allowbadttl)
                                goto bad;
                }
        }
-       if (m->m_pkthdr.rcvif->if_hwassist == 0)
-               m->m_pkthdr.csum_flags = 0;
-
-       if ((m->m_pkthdr.csum_flags & CSUM_TCP_SUM16) && ip->ip_p != IPPROTO_TCP)
-               m->m_pkthdr.csum_flags = 0;
+       if ((IF_HWASSIST_CSUM_FLAGS(m->m_pkthdr.rcvif->if_hwassist) == 0) 
+           || (apple_hwcksum_rx == 0) ||
+          ((m->m_pkthdr.csum_flags & CSUM_TCP_SUM16) && ip->ip_p != IPPROTO_TCP)) {
+                       m->m_pkthdr.csum_flags = 0; /* invalidate HW generated checksum flags */
+       }
 
        if (m->m_pkthdr.csum_flags & CSUM_IP_CHECKED) {
                sum = !(m->m_pkthdr.csum_flags & CSUM_IP_VALID);
-       } else {
+       } else if (!(m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) ||
+           apple_hwcksum_tx == 0) {
+               /*
+                * Either this is not loopback packet coming from an interface
+                * that does not support checksum offloading, or it is loopback
+                * packet that has undergone software checksumming at the send
+                * side because apple_hwcksum_tx was set to 0.  In this case,
+                * calculate the checksum in software to validate the packet.
+                */
                sum = in_cksum(m, hlen);
+       } else {
+               /*
+                * This is a loopback packet without any valid checksum since
+                * the send side has bypassed it (apple_hwcksum_tx set to 1).
+                * We get here because apple_hwcksum_rx was set to 0, and so
+                * we pretend that all is well.
+                */
+               sum = 0;
+               m->m_pkthdr.csum_flags |= CSUM_DATA_VALID | CSUM_PSEUDO_HDR |
+                   CSUM_IP_CHECKED | CSUM_IP_VALID;
+                m->m_pkthdr.csum_data = 0xffff;
        }
        if (sum) {
-               ipstat.ips_badsum++;
+               OSAddAtomic(1, &ipstat.ips_badsum);
                goto bad;
        }
 
+       DTRACE_IP6(receive, struct mbuf *, m, struct inpcb *, NULL, 
+               struct ip *, ip, struct ifnet *, m->m_pkthdr.rcvif,
+               struct ip *, ip, struct ip6_hdr *, NULL);
+
+       /*
+        * Naively assume we can attribute inbound data to the route we would
+        * use to send to this destination. Asymetric routing breaks this
+        * assumption, but it still allows us to account for traffic from
+        * a remote node in the routing table.
+        * this has a very significant performance impact so we bypass
+        * if nstat_collect is disabled. We may also bypass if the
+        * protocol is tcp in the future because tcp will have a route that
+        * we can use to attribute the data to. That does mean we would not
+        * account for forwarded tcp traffic.
+        */
+       if (nstat_collect) {
+               struct rtentry *rt =
+                   ifnet_cached_rtlookup_inet(m->m_pkthdr.rcvif, ip->ip_src);
+               if (rt != NULL) {
+                       nstat_route_rx(rt, 1, m->m_pkthdr.len, 0);
+                       rtfree(rt);
+               }
+       }
+
        /*
         * Convert fields to host representation.
         */
+#if BYTE_ORDER != BIG_ENDIAN
        NTOHS(ip->ip_len);
+#endif
+       
        if (ip->ip_len < hlen) {
-               ipstat.ips_badlen++;
+               OSAddAtomic(1, &ipstat.ips_badlen);
                goto bad;
        }
-       NTOHS(ip->ip_off);
 
+#if BYTE_ORDER != BIG_ENDIAN
+       NTOHS(ip->ip_off);
+#endif
        /*
         * Check that the amount of data in the buffers
         * is as at least much as the IP header would have us expect.
@@ -481,7 +863,7 @@ ip_input(struct mbuf *m)
         */
        if (m->m_pkthdr.len < ip->ip_len) {
 tooshort:
-               ipstat.ips_tooshort++;
+               OSAddAtomic(1, &ipstat.ips_tooshort);
                goto bad;
        }
        if (m->m_pkthdr.len > ip->ip_len) {
@@ -496,26 +878,33 @@ tooshort:
                        m_adj(m, ip->ip_len - m->m_pkthdr.len);
        }
 
+#if PF
+       /* Invoke inbound packet filter */
+       if (PF_IS_ENABLED) { 
+               int error;
+               error = pf_af_hook(m->m_pkthdr.rcvif, NULL, &m, AF_INET, TRUE);
+               if (error != 0) {
+                       if (m != NULL) {
+                               panic("%s: unexpected packet %p\n", __func__, m);
+                               /* NOTREACHED */
+                       }
+                       /* Already freed by callee */
+                       return;
+               } 
+               ip = mtod(m, struct ip *);
+               hlen = IP_VHL_HL(ip->ip_vhl) << 2;
+       }
+#endif /* PF */
+
 #if IPSEC
        if (ipsec_bypass == 0 && ipsec_gethist(m, NULL))
                goto pass;
 #endif
 
-       /*
-        * IpHack's section.
-        * Right now when no processing on packet has done
-        * and it is still fresh out of network we do our black
-        * deals with it.
-        * - Firewall: deny/allow/divert
-        * - Xlate: translate packet's addr/port (NAT).
-        * - Pipe: pass pkt through dummynet.
-        * - Wrap: fake packet's addr/port <unimpl.>
-        * - Encapsulate: put it in another IP and send out. <unimp.>
-        */
-
-#if defined(IPFIREWALL) && defined(DUMMYNET)
+#if IPFIREWALL
+#if DUMMYNET
 iphack:
-#endif
+#endif /* DUMMYNET */
        /*
         * Check if we want to allow this packet to be processed.
         * Consider it to be bad if not.
@@ -523,50 +912,54 @@ iphack:
        if (fr_checkp) {
                struct  mbuf    *m1 = m;
 
-               if ((*fr_checkp)(ip, hlen, m->m_pkthdr.rcvif, 0, &m1) || !m1)
+               if (fr_checkp(ip, hlen, m->m_pkthdr.rcvif, 0, &m1) || !m1) {
                        return;
+               }
                ip = mtod(m = m1, struct ip *);
        }
-       if (fw_enable && ip_fw_chk_ptr) {
+       if (fw_enable && IPFW_LOADED) {
 #if IPFIREWALL_FORWARD
                /*
                 * If we've been forwarded from the output side, then
                 * skip the firewall a second time
                 */
-               if (ip_fw_fwd_addr)
+               if (args.next_hop)
                        goto ours;
 #endif /* IPFIREWALL_FORWARD */
-               /*
-                * See the comment in ip_output for the return values
-                * produced by the firewall.
-                */
-               i = (*ip_fw_chk_ptr)(&ip,
-                   hlen, NULL, &divert_cookie, &m, &rule, &ip_fw_fwd_addr);
+
+               args.m = m;
+
+               i = ip_fw_chk_ptr(&args);
+               m = args.m;
+
                if ( (i & IP_FW_PORT_DENY_FLAG) || m == NULL) { /* drop */
-               if (m)
-                m_freem(m);
+                       if (m)
+                               m_freem(m);
                        return;
-        }
+               }
                ip = mtod(m, struct ip *); /* just in case m changed */
-               if (i == 0 && ip_fw_fwd_addr == NULL)   /* common case */
+               
+               if (i == 0 && args.next_hop == NULL) {  /* common case */
                        goto pass;
+               }
 #if DUMMYNET
-        if ((i & IP_FW_PORT_DYNT_FLAG) != 0) {
-            /* send packet to the appropriate pipe */
-            dummynet_io(i&0xffff,DN_TO_IP_IN,m,NULL,NULL,0, rule);
+                if (DUMMYNET_LOADED && (i & IP_FW_PORT_DYNT_FLAG) != 0) {
+                       /* Send packet to the appropriate pipe */
+                       ip_dn_io_ptr(m, i&0xffff, DN_TO_IP_IN, &args);
                        return;
                }
-#endif
+#endif /* DUMMYNET */
 #if IPDIVERT
                if (i != 0 && (i & IP_FW_PORT_DYNT_FLAG) == 0) {
                        /* Divert or tee packet */
-                       divert_info = i;
+                       div_info = i;
                        goto ours;
                }
 #endif
 #if IPFIREWALL_FORWARD
-               if (i == 0 && ip_fw_fwd_addr != NULL)
+               if (i == 0 && args.next_hop != NULL) {
                        goto pass;
+               }
 #endif
                /*
                 * if we get here, the packet must be dropped
@@ -574,6 +967,7 @@ iphack:
                m_freem(m);
                return;
        }
+#endif /* IPFIREWALL */
 pass:
 
        /*
@@ -583,9 +977,10 @@ pass:
         * to be sent and the original packet to be freed).
         */
        ip_nhops = 0;           /* for source routed packets */
-       if (hlen > sizeof (struct ip) && ip_dooptions(m)) {
-#if IPFIREWALL_FORWARD
-               ip_fw_fwd_addr = NULL;
+#if IPFIREWALL
+       if (hlen > sizeof (struct ip) && ip_dooptions(m, 0, args.next_hop)) {
+#else
+       if (hlen > sizeof (struct ip) && ip_dooptions(m, 0, NULL)) {
 #endif
                return;
        }
@@ -613,8 +1008,12 @@ pass:
         * Cache the destination address of the packet; this may be
         * changed by use of 'ipfw fwd'.
         */
-       pkt_dst = ip_fw_fwd_addr == NULL ?
-           ip->ip_dst : ip_fw_fwd_addr->sin_addr;
+#if IPFIREWALL
+       pkt_dst = args.next_hop == NULL ?
+           ip->ip_dst : args.next_hop->sin_addr;
+#else
+       pkt_dst = ip->ip_dst;
+#endif
 
        /*
         * Enable a consistency check between the destination address
@@ -631,41 +1030,70 @@ pass:
         * the packets are received.
         */
        checkif = ip_checkinterface && (ipforwarding == 0) && 
-           ((m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) == 0) &&
-           (ip_fw_fwd_addr == NULL);
-
-       TAILQ_FOREACH(ia, &in_ifaddrhead, ia_link) {
-#define        satosin(sa)     ((struct sockaddr_in *)(sa))
+           ((m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) == 0)
+#if IPFIREWALL
+           && (args.next_hop == NULL);
+#else
+               ;
+#endif
 
-               if (IA_SIN(ia)->sin_addr.s_addr == INADDR_ANY)
-                       goto ours;
-               
+       /*
+        * Check for exact addresses in the hash bucket.
+        */
+       lck_rw_lock_shared(in_ifaddr_rwlock);
+       TAILQ_FOREACH(ia, INADDR_HASH(pkt_dst.s_addr), ia_hash) {
                /*
                 * If the address matches, verify that the packet
                 * arrived via the correct interface if checking is
                 * enabled.
                 */
+               IFA_LOCK_SPIN(&ia->ia_ifa);
                if (IA_SIN(ia)->sin_addr.s_addr == pkt_dst.s_addr && 
-                   (!checkif || ia->ia_ifp == m->m_pkthdr.rcvif))
+                   (!checkif || ia->ia_ifp == m->m_pkthdr.rcvif)) {
+                       IFA_UNLOCK(&ia->ia_ifa);
+                       lck_rw_done(in_ifaddr_rwlock);
                        goto ours;
-               /*
-                * Only accept broadcast packets that arrive via the
-                * matching interface.  Reception of forwarded directed
-                * broadcasts would be handled via ip_forward() and
-                * ether_output() with the loopback into the stack for
-                * SIMPLEX interfaces handled by ether_output().
-                */
-               if (ia->ia_ifp == m->m_pkthdr.rcvif &&
-                   ia->ia_ifp && ia->ia_ifp->if_flags & IFF_BROADCAST) {
+               }
+               IFA_UNLOCK(&ia->ia_ifa);
+       }
+       lck_rw_done(in_ifaddr_rwlock);
+
+       /*
+        * Check for broadcast addresses.
+        *
+        * Only accept broadcast packets that arrive via the matching
+        * interface.  Reception of forwarded directed broadcasts would be
+        * handled via ip_forward() and ether_frameout() with the loopback
+        * into the stack for SIMPLEX interfaces handled by ether_frameout().
+        */
+       if (m->m_pkthdr.rcvif->if_flags & IFF_BROADCAST) {
+               struct ifaddr *ifa;
+               struct ifnet *ifp = m->m_pkthdr.rcvif;
+
+               ifnet_lock_shared(ifp);
+               TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
+                       IFA_LOCK_SPIN(ifa);
+                       if (ifa->ifa_addr->sa_family != AF_INET) {
+                               IFA_UNLOCK(ifa);
+                               continue;
+                       }
+                       ia = ifatoia(ifa);
                        if (satosin(&ia->ia_broadaddr)->sin_addr.s_addr ==
-                           pkt_dst.s_addr)
-                               goto ours;
-                       if (ia->ia_netbroadcast.s_addr == pkt_dst.s_addr)
+                           pkt_dst.s_addr || ia->ia_netbroadcast.s_addr ==
+                           pkt_dst.s_addr) {
+                               IFA_UNLOCK(ifa);
+                               ifnet_lock_done(ifp);
                                goto ours;
+                       }
+                       IFA_UNLOCK(ifa);
                }
+               ifnet_lock_done(ifp);
        }
+
        if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr))) {
                struct in_multi *inm;
+               struct ifnet *ifp = m->m_pkthdr.rcvif;
+#if MROUTING
                if (ip_mrouter) {
                        /*
                         * If we are acting as a multicast router, all
@@ -675,34 +1103,40 @@ pass:
                         * ip_mforward() returns a non-zero value, the packet
                         * must be discarded, else it may be accepted below.
                         */
-                       if (ip_mforward(ip, m->m_pkthdr.rcvif, m, 0) != 0) {
-                               ipstat.ips_cantforward++;
+                       lck_mtx_lock(ip_mutex);
+                       if (ip_mforward && ip_mforward(ip, ifp, m, 0) != 0) {
+                               OSAddAtomic(1, &ipstat.ips_cantforward);
                                m_freem(m);
+                               lck_mtx_unlock(ip_mutex);
                                return;
                        }
 
                        /*
-                        * The process-level routing demon needs to receive
+                        * The process-level routing daemon needs to receive
                         * all multicast IGMP packets, whether or not this
                         * host belongs to their destination groups.
                         */
                        if (ip->ip_p == IPPROTO_IGMP)
                                goto ours;
-                       ipstat.ips_forward++;
+                       OSAddAtomic(1, &ipstat.ips_forward);
                }
+#endif /* MROUTING */
                /*
                 * See if we belong to the destination multicast group on the
                 * arrival interface.
                 */
-               IN_LOOKUP_MULTI(ip->ip_dst, m->m_pkthdr.rcvif, inm);
+               in_multihead_lock_shared();
+               IN_LOOKUP_MULTI(&ip->ip_dst, ifp, inm);
+               in_multihead_lock_done();
                if (inm == NULL) {
-                       ipstat.ips_notmember++;
+                       OSAddAtomic(1, &ipstat.ips_notmember);
                        m_freem(m);
                        return;
                }
+               INM_REMREF(inm);
                goto ours;
        }
-       if (ip->ip_dst.s_addr == (u_long)INADDR_BROADCAST)
+       if (ip->ip_dst.s_addr == (u_int32_t)INADDR_BROADCAST)
                goto ours;
        if (ip->ip_dst.s_addr == INADDR_ANY)
                goto ours;
@@ -715,7 +1149,7 @@ pass:
                struct udpiphdr *ui;
                if (m->m_len < sizeof(struct udpiphdr)
                    && (m = m_pullup(m, sizeof(struct udpiphdr))) == 0) {
-                       udpstat.udps_hdrops++;
+                       OSAddAtomic(1, &udpstat.udps_hdrops);
                        return;
                }
                ui = mtod(m, struct udpiphdr *);
@@ -742,25 +1176,18 @@ pass:
         * Not for us; forward if possible and desirable.
         */
        if (ipforwarding == 0) {
-               ipstat.ips_cantforward++;
+               OSAddAtomic(1, &ipstat.ips_cantforward);
                m_freem(m);
-       } else
-               ip_forward(m, 0);
-#if IPFIREWALL_FORWARD
-       ip_fw_fwd_addr = NULL;
+       } else {
+#if IPFIREWALL
+               ip_forward(m, 0, args.next_hop);
+#else
+               ip_forward(m, 0, NULL);
 #endif
+       }
        return;
 
 ours:
-#ifndef __APPLE__
-       /* Darwin does not have an if_data in ifaddr */
-       /* Count the packet in the ip address stats */
-       if (ia != NULL) {
-               ia->ia_ifa.if_ipackets++;
-               ia->ia_ifa.if_ibytes += m->m_pkthdr.len;
-       }
-#endif
-
        /*
         * If offset or IP_MF are set, must reassemble.
         * Otherwise, nothing need be done.
@@ -770,21 +1197,40 @@ ours:
         */
        if (ip->ip_off & (IP_MF | IP_OFFMASK | IP_RF)) {
 
-#if 0  /*
-        * Reassembly should be able to treat a mbuf cluster, for later
-        * operation of contiguous protocol headers on the cluster. (KAME)
-        */
-               if (m->m_flags & M_EXT) {               /* XXX */
-                       if ((m = m_pullup(m, hlen)) == 0) {
-                               ipstat.ips_toosmall++;
-#if IPFIREWALL_FORWARD
-                               ip_fw_fwd_addr = NULL;
-#endif
-                               return;
+               /* If maxnipq is 0, never accept fragments. */
+               if (maxnipq == 0) {
+
+                       OSAddAtomic(1, &ipstat.ips_fragments);
+                       OSAddAtomic(1, &ipstat.ips_fragdropped);
+                       goto bad;
+               }
+               
+               /*
+                * If we will exceed the number of fragments in queues, timeout the
+                * oldest fragemented packet to make space.
+                */
+               lck_mtx_lock(ip_mutex); 
+               if (currentfrags >= maxfrags) {
+                       fp = TAILQ_LAST(&ipq_list, ipq_list);
+                       OSAddAtomic(fp->ipq_nfrags, &ipstat.ips_fragtimeout);
+                       
+                       if (ip->ip_id == fp->ipq_id &&
+                               ip->ip_src.s_addr == fp->ipq_src.s_addr &&
+                               ip->ip_dst.s_addr == fp->ipq_dst.s_addr &&
+                               ip->ip_p == fp->ipq_p) {
+                               /*
+                                * If we match the fragment queue we were going to
+                                * discard, drop this packet too.
+                                */
+                               OSAddAtomic(1, &ipstat.ips_fragdropped);
+                               ip_freef(fp);
+                               lck_mtx_unlock(ip_mutex); 
+                               goto bad;
                        }
-                       ip = mtod(m, struct ip *);
+                       
+                       ip_freef(fp);
                }
-#endif
+
                sum = IPREASS_HASH(ip->ip_src.s_addr, ip->ip_id);
                /*
                 * Look for queue of fragments
@@ -794,118 +1240,127 @@ ours:
                        if (ip->ip_id == fp->ipq_id &&
                            ip->ip_src.s_addr == fp->ipq_src.s_addr &&
                            ip->ip_dst.s_addr == fp->ipq_dst.s_addr &&
+#if CONFIG_MACF_NET
+                           mac_ipq_label_compare(m, fp) &&
+#endif
                            ip->ip_p == fp->ipq_p)
                                goto found;
 
-               fp = 0;
-
-               /* check if there's a place for the new queue */
-               if (nipq > maxnipq) {
+               /*
+                * Enforce upper bound on number of fragmented packets
+                * for which we attempt reassembly;
+                * If maxnipq is -1, accept all fragments without limitation.
+                */
+               if ((nipq > maxnipq) && (maxnipq > 0)) {
                    /*
-                    * drop something from the tail of the current queue
-                    * before proceeding further
+                    * drop the oldest fragment before proceeding further
                     */
-                   if (ipq[sum].prev == &ipq[sum]) {   /* gak */
-                       for (i = 0; i < IPREASS_NHASH; i++) {
-                           if (ipq[i].prev != &ipq[i]) {
-                               ip_freef(ipq[i].prev);
-                               break;
-                           }
-                       }
-                   } else
-                       ip_freef(ipq[sum].prev);
+                   fp = TAILQ_LAST(&ipq_list, ipq_list);
+                   OSAddAtomic(fp->ipq_nfrags, &ipstat.ips_fragtimeout);
+                   ip_freef(fp);
                }
+
+               fp = NULL;
+
 found:
                /*
                 * Adjust ip_len to not reflect header,
-                * set ip_mff if more fragments are expected,
                 * convert offset of this to bytes.
                 */
                ip->ip_len -= hlen;
-               mff = (ip->ip_off & IP_MF) != 0;
-               if (mff) {
+               if (ip->ip_off & IP_MF) {
                        /*
                         * Make sure that fragments have a data length
-                        * that's a non-zero multiple of 8 bytes.
+                                * that's a non-zero multiple of 8 bytes.
                         */
                        if (ip->ip_len == 0 || (ip->ip_len & 0x7) != 0) {
-                               ipstat.ips_toosmall++; /* XXX */
+                               OSAddAtomic(1, &ipstat.ips_toosmall);
+                               lck_mtx_unlock(ip_mutex);
                                goto bad;
                        }
                        m->m_flags |= M_FRAG;
+               } else {
+                       /* Clear the flag in case packet comes from loopback */
+                       m->m_flags &= ~M_FRAG;
                }
                ip->ip_off <<= 3;
 
                /*
-                * If datagram marked as having more fragments
-                * or if this is not the first fragment,
-                * attempt reassembly; if it succeeds, proceed.
+                * Attempt reassembly; if it succeeds, proceed.
+                * ip_reass() will return a different mbuf, and update
+                * the divert info in div_info and args.divert_rule.
                 */
-               if (mff || ip->ip_off) {
-                       ipstat.ips_fragments++;
+                       OSAddAtomic(1, &ipstat.ips_fragments);
                        m->m_pkthdr.header = ip;
 #if IPDIVERT
-                       m = ip_reass(m,
-                           fp, &ipq[sum], &divert_info, &divert_cookie);
+                       m = ip_reass(m, fp, &ipq[sum],
+                           (u_int16_t *)&div_info, &args.divert_rule);
 #else
                        m = ip_reass(m, fp, &ipq[sum]);
 #endif
                        if (m == 0) {
-#if    IPFIREWALL_FORWARD
-                               ip_fw_fwd_addr = NULL;
-#endif
+                               lck_mtx_unlock(ip_mutex);
                                return;
                        }
-                       ipstat.ips_reassembled++;
+                       OSAddAtomic(1, &ipstat.ips_reassembled);
                        ip = mtod(m, struct ip *);
                        /* Get the header length of the reassembled packet */
                        hlen = IP_VHL_HL(ip->ip_vhl) << 2;
+
 #if IPDIVERT
                        /* Restore original checksum before diverting packet */
-                       if (divert_info != 0) {
+                       if (div_info != 0) {
                                ip->ip_len += hlen;
+
+#if BYTE_ORDER != BIG_ENDIAN
                                HTONS(ip->ip_len);
                                HTONS(ip->ip_off);
+#endif
+                               
                                ip->ip_sum = 0;
                                ip->ip_sum = in_cksum(m, hlen);
+
+#if BYTE_ORDER != BIG_ENDIAN
                                NTOHS(ip->ip_off);
                                NTOHS(ip->ip_len);
+#endif
+                               
                                ip->ip_len -= hlen;
                        }
 #endif
+               lck_mtx_unlock(ip_mutex);
                } else
-                       if (fp)
-                               ip_freef(fp);
-       } else
                ip->ip_len -= hlen;
 
 #if IPDIVERT
        /*
         * Divert or tee packet to the divert protocol if required.
         *
-        * If divert_info is zero then cookie should be too, so we shouldn't
+        * If div_info is zero then cookie should be too, so we shouldn't
         * need to clear them here.  Assume divert_packet() does so also.
         */
-       if (divert_info != 0) {
+       if (div_info != 0) {
                struct mbuf *clone = NULL;
 
                /* Clone packet if we're doing a 'tee' */
-               if ((divert_info & IP_FW_PORT_TEE_FLAG) != 0)
+               if ((div_info & IP_FW_PORT_TEE_FLAG) != 0)
                        clone = m_dup(m, M_DONTWAIT);
 
                /* Restore packet header fields to original values */
                ip->ip_len += hlen;
+
+#if BYTE_ORDER != BIG_ENDIAN
                HTONS(ip->ip_len);
                HTONS(ip->ip_off);
-
+#endif
                /* Deliver packet to divert input routine */
-               ip_divert_cookie = divert_cookie;
-               divert_packet(m, 1, divert_info & 0xffff);
-               ipstat.ips_delivered++;
+               OSAddAtomic(1, &ipstat.ips_delivered);
+               divert_packet(m, 1, div_info & 0xffff, args.divert_rule);
 
                /* If 'tee', continue with original packet */
-               if (clone == NULL)
+               if (clone == NULL) {
                        return;
+               }
                m = clone;
                ip = mtod(m, struct ip *);
        }
@@ -917,61 +1372,60 @@ found:
         * note that we do not visit this with protocols with pcb layer
         * code - like udp/tcp/raw ip.
         */
-       if (ipsec_bypass == 0 && (ip_protox[ip->ip_p]->pr_flags & PR_LASTHDR) != 0 &&
-           ipsec4_in_reject(m, NULL)) {
-               ipsecstat.in_polvio++;
-               goto bad;
+       if (ipsec_bypass == 0 && (ip_protox[ip->ip_p]->pr_flags & PR_LASTHDR) != 0) {
+               if (ipsec4_in_reject(m, NULL)) {
+                       IPSEC_STAT_INCREMENT(ipsecstat.in_polvio);
+                       goto bad;       
+               }
        }
 #endif
 
        /*
         * Switch out to protocol's input routine.
         */
-       ipstat.ips_delivered++;
+       OSAddAtomic(1, &ipstat.ips_delivered);
        {
-               KERNEL_DEBUG(DBG_LAYER_END, ip->ip_dst.s_addr, 
-                    ip->ip_src.s_addr, ip->ip_p, ip->ip_off, ip->ip_len);
-
-               (*ip_protox[ip->ip_p]->pr_input)(m, hlen);
-#if    IPFIREWALL_FORWARD
-               ip_fw_fwd_addr = NULL;  /* tcp needed it */
+#if IPFIREWALL
+               if (args.next_hop && ip->ip_p == IPPROTO_TCP) {
+                       /* TCP needs IPFORWARD info if available */
+                       struct m_tag *fwd_tag;
+                       struct ip_fwd_tag       *ipfwd_tag;
+                       
+                       fwd_tag = m_tag_create(KERNEL_MODULE_TAG_ID,
+                           KERNEL_TAG_TYPE_IPFORWARD, sizeof (*ipfwd_tag),
+                           M_NOWAIT, m);
+                       if (fwd_tag == NULL) {
+                               goto bad;
+                       }
+                       
+                       ipfwd_tag = (struct ip_fwd_tag *)(fwd_tag+1);
+                       ipfwd_tag->next_hop = args.next_hop;
+
+                       m_tag_prepend(m, fwd_tag);
+       
+                       KERNEL_DEBUG(DBG_LAYER_END, ip->ip_dst.s_addr, 
+                            ip->ip_src.s_addr, ip->ip_p, ip->ip_off, ip->ip_len);
+       
+       
+                       /* TCP deals with its own locking */
+                       ip_proto_dispatch_in(m, hlen, ip->ip_p, 0);
+               } else {
+                       KERNEL_DEBUG(DBG_LAYER_END, ip->ip_dst.s_addr, 
+                            ip->ip_src.s_addr, ip->ip_p, ip->ip_off, ip->ip_len);
+               
+                       ip_proto_dispatch_in(m, hlen, ip->ip_p, 0);
+               }
+#else
+               ip_proto_dispatch_in(m, hlen, ip->ip_p, 0);
 #endif
+               
                return;
        }
 bad:
-#if    IPFIREWALL_FORWARD
-       ip_fw_fwd_addr = NULL;
-#endif
        KERNEL_DEBUG(DBG_LAYER_END, 0,0,0,0,0);
        m_freem(m);
 }
 
-/*
- * IP software interrupt routine - to go away sometime soon
- */
-void
-ipintr(void)
-{
-       int s;
-       struct mbuf *m;
-
-       KERNEL_DEBUG(DBG_FNC_IP_INPUT | DBG_FUNC_START, 0,0,0,0,0);
-
-       while(1) {
-               s = splimp();
-               IF_DEQUEUE(&ipintrq, m);
-               splx(s);
-               if (m == 0) {
-                 KERNEL_DEBUG(DBG_FNC_IP_INPUT | DBG_FUNC_END, 0,0,0,0,0);
-                 return;
-               }
-
-               ip_input(m);
-       }
-}
-
-NETISR_SET(NETISR_IP, ipintr);
-  
 /*
  * Take incoming datagram fragment and try to reassemble it into
  * whole datagram.  If a chain for reassembly of this datagram already
@@ -983,28 +1437,25 @@ NETISR_SET(NETISR_IP, ipintr);
 
 static struct mbuf *
 #if IPDIVERT
-ip_reass(m, fp, where, divinfo, divcookie)
-#else
-ip_reass(m, fp, where)
-#endif
-       register struct mbuf *m;
-       register struct ipq *fp;
-       struct   ipq    *where;
-#if IPDIVERT
+ip_reass(struct mbuf *m, struct ipq *fp, struct ipq *where,
 #ifdef IPDIVERT_44
-       u_int32_t *divinfo;
-#else
-       u_int16_t *divinfo;
-#endif
-       u_int16_t *divcookie;
-#endif
+        u_int32_t *divinfo,
+#else /* IPDIVERT_44 */
+        u_int16_t *divinfo,
+#endif /* IPDIVERT_44 */
+        u_int16_t *divcookie)
+#else /* IPDIVERT */
+ip_reass(struct mbuf *m, struct ipq *fp, struct ipq *where)
+#endif /* IPDIVERT */
 {
        struct ip *ip = mtod(m, struct ip *);
-       register struct mbuf *p = 0, *q, *nq;
+       struct mbuf *p = 0, *q, *nq;
        struct mbuf *t;
        int hlen = IP_VHL_HL(ip->ip_vhl) << 2;
        int i, next;
+       u_int8_t ecn, ecn0;
 
+       lck_mtx_assert(ip_mutex, LCK_MTX_ASSERT_OWNED);
        /*
         * Presence of header sizes in mbufs
         * would confuse code below.
@@ -1018,20 +1469,20 @@ ip_reass(m, fp, where)
         * If first fragment to arrive, create a reassembly queue.
         */
        if (fp == 0) {
-               /*
-                * Enforce upper bound on number of fragmented packets
-                * for which we attempt reassembly;
-                * If maxfrag is 0, never accept fragments.
-                * If maxfrag is -1, accept all fragments without limitation.
-                */
-               if ((ip_maxfragpackets >= 0) && (ip_nfragpackets >= ip_maxfragpackets))
-                       goto dropfrag;
-               ip_nfragpackets++;
                if ((t = m_get(M_DONTWAIT, MT_FTABLE)) == NULL)
                        goto dropfrag;
                fp = mtod(t, struct ipq *);
+#if CONFIG_MACF_NET
+               if (mac_ipq_label_init(fp, M_NOWAIT) != 0) {
+                       m_free(t);
+                       fp = NULL;
+                       goto dropfrag;
+               }
+               mac_ipq_label_associate(m, fp);
+#endif
                insque((void*)fp, (void*)where);
                nipq++;
+               fp->ipq_nfrags = 1;
                fp->ipq_ttl = IPFRAGTTL;
                fp->ipq_p = ip->ip_p;
                fp->ipq_id = ip->ip_id;
@@ -1047,11 +1498,33 @@ ip_reass(m, fp, where)
 #endif
                fp->ipq_div_cookie = 0;
 #endif
+               TAILQ_INSERT_HEAD(&ipq_list, fp, ipq_list);
                goto inserted;
+       } else {
+               fp->ipq_nfrags++;
+#if CONFIG_MACF_NET
+               mac_ipq_label_update(m, fp);
+#endif
        }
 
 #define GETIP(m)       ((struct ip*)((m)->m_pkthdr.header))
 
+       /*
+        * Handle ECN by comparing this segment with the first one;
+        * if CE is set, do not lose CE.
+        * drop if CE and not-ECT are mixed for the same packet.
+        */
+       ecn = ip->ip_tos & IPTOS_ECN_MASK;
+       ecn0 = GETIP(fp->ipq_frags)->ip_tos & IPTOS_ECN_MASK;
+       if (ecn == IPTOS_ECN_CE) {
+               if (ecn0 == IPTOS_ECN_NOTECT)
+                       goto dropfrag;
+               if (ecn0 != IPTOS_ECN_CE)
+                       GETIP(fp->ipq_frags)->ip_tos |= IPTOS_ECN_CE;
+       }
+       if (ecn == IPTOS_ECN_NOTECT && ecn0 != IPTOS_ECN_NOTECT)
+               goto dropfrag;
+
        /*
         * Find a segment which begins after this one does.
         */
@@ -1102,38 +1575,60 @@ ip_reass(m, fp, where)
                }
                nq = q->m_nextpkt;
                m->m_nextpkt = nq;
+               OSAddAtomic(1, &ipstat.ips_fragdropped);
+               fp->ipq_nfrags--;
                m_freem(q);
        }
 
 inserted:
+       currentfrags++;
 
 #if IPDIVERT
        /*
         * Transfer firewall instructions to the fragment structure.
-        * Any fragment diverting causes the whole packet to divert.
+        * Only trust info in the fragment at offset 0.
         */
+       if (ip->ip_off == 0) {
 #ifdef IPDIVERT_44
        fp->ipq_div_info = *divinfo;
 #else
        fp->ipq_divert = *divinfo;
 #endif
        fp->ipq_div_cookie = *divcookie;
+       }
        *divinfo = 0;
        *divcookie = 0;
 #endif
 
        /*
-        * Check for complete reassembly.
+        * Check for complete reassembly and perform frag per packet
+        * limiting.
+        *
+        * Frag limiting is performed here so that the nth frag has
+        * a chance to complete the packet before we drop the packet.
+        * As a result, n+1 frags are actually allowed per packet, but
+        * only n will ever be stored. (n = maxfragsperpacket.)
+        *
         */
        next = 0;
        for (p = NULL, q = fp->ipq_frags; q; p = q, q = q->m_nextpkt) {
-               if (GETIP(q)->ip_off != next)
+               if (GETIP(q)->ip_off != next) {
+                       if (fp->ipq_nfrags > maxfragsperpacket) {
+                               OSAddAtomic(fp->ipq_nfrags, &ipstat.ips_fragdropped);
+                               ip_freef(fp);
+                       }
                        return (0);
+               }
                next += GETIP(q)->ip_len;
        }
        /* Make sure the last packet didn't have the IP_MF flag */
-       if (p->m_flags & M_FRAG)
+       if (p->m_flags & M_FRAG) {
+               if (fp->ipq_nfrags > maxfragsperpacket) {
+                       OSAddAtomic(fp->ipq_nfrags, &ipstat.ips_fragdropped);
+                       ip_freef(fp);
+               }
                return (0);
+       }
 
        /*
         * Reassembly is complete.  Make sure the packet is a sane size.
@@ -1141,7 +1636,8 @@ inserted:
        q = fp->ipq_frags;
        ip = GETIP(q);
        if (next + (IP_VHL_HL(ip->ip_vhl) << 2) > IP_MAXPACKET) {
-               ipstat.ips_toolong++;
+               OSAddAtomic(1, &ipstat.ips_toolong);
+               OSAddAtomic(fp->ipq_nfrags, &ipstat.ips_fragdropped);
                ip_freef(fp);
                return (0);
        }
@@ -1179,6 +1675,10 @@ inserted:
        *divcookie = fp->ipq_div_cookie;
 #endif
 
+#if CONFIG_MACF_NET
+       mac_mbuf_label_associate_ipq(fp, m);
+       mac_ipq_label_destroy(fp);
+#endif
        /*
         * Create header for new ip packet by
         * modifying header of first packet;
@@ -1189,14 +1689,15 @@ inserted:
        ip->ip_src = fp->ipq_src;
        ip->ip_dst = fp->ipq_dst;
        remque((void*)fp);
+       TAILQ_REMOVE(&ipq_list, fp, ipq_list);
+       currentfrags -= fp->ipq_nfrags;
        nipq--;
        (void) m_free(dtom(fp));
-       ip_nfragpackets--;
        m->m_len += (IP_VHL_HL(ip->ip_vhl) << 2);
        m->m_data -= (IP_VHL_HL(ip->ip_vhl) << 2);
        /* some debugging cruft by sklower, below, will go away soon */
        if (m->m_flags & M_PKTHDR) { /* XXX this should be done elsewhere */
-               register int plen = 0;
+               int plen = 0;
                for (t = m; t; t = t->m_next)
                        plen += t->m_len;
                m->m_pkthdr.len = plen;
@@ -1208,7 +1709,9 @@ dropfrag:
        *divinfo = 0;
        *divcookie = 0;
 #endif
-       ipstat.ips_fragdropped++;
+       OSAddAtomic(1, &ipstat.ips_fragdropped);
+       if (fp != 0)
+               fp->ipq_nfrags--;
        m_freem(m);
        return (0);
 
@@ -1220,19 +1723,14 @@ dropfrag:
  * associated datagrams.
  */
 static void
-ip_freef(fp)
-       struct ipq *fp;
+ip_freef(struct ipq *fp)
 {
-       register struct mbuf *q;
-
-       while (fp->ipq_frags) {
-               q = fp->ipq_frags;
-               fp->ipq_frags = q->m_nextpkt;
-               m_freem(q);
-       }
+       lck_mtx_assert(ip_mutex, LCK_MTX_ASSERT_OWNED);
+       currentfrags -= fp->ipq_nfrags;
+       m_freem_list(fp->ipq_frags);
        remque((void*)fp);
+       TAILQ_REMOVE(&ipq_list, fp, ipq_list);
        (void) m_free(dtom(fp));
-       ip_nfragpackets--;
        nipq--;
 }
 
@@ -1242,12 +1740,11 @@ ip_freef(fp)
  * queue, discard it.
  */
 void
-ip_slowtimo()
+ip_slowtimo(void)
 {
-       register struct ipq *fp;
-       int s = splnet();
+       struct ipq *fp;
        int i;
-
+       lck_mtx_lock(ip_mutex);
        for (i = 0; i < IPREASS_NHASH; i++) {
                fp = ipq[i].next;
                if (fp == 0)
@@ -1256,7 +1753,7 @@ ip_slowtimo()
                        --fp->ipq_ttl;
                        fp = fp->next;
                        if (fp->prev->ipq_ttl == 0) {
-                               ipstat.ips_fragtimeout++;
+                               OSAddAtomic(fp->ipq_nfrags, &ipstat.ips_fragtimeout);
                                ip_freef(fp->prev);
                        }
                }
@@ -1266,33 +1763,34 @@ ip_slowtimo()
         * (due to the limit being lowered), drain off
         * enough to get down to the new limit.
         */
+       if (maxnipq >= 0 && nipq > maxnipq) {
        for (i = 0; i < IPREASS_NHASH; i++) {
-               if (ip_maxfragpackets >= 0) {
-                       while ((ip_nfragpackets > ip_maxfragpackets) &&
+                       while (nipq > maxnipq &&
                                (ipq[i].next != &ipq[i])) {
-                               ipstat.ips_fragdropped++;
+                               OSAddAtomic(ipq[i].next->ipq_nfrags, &ipstat.ips_fragdropped);
                                ip_freef(ipq[i].next);
                        }
                }
        }
-       ipflow_slowtimo();
-       splx(s);
+       lck_mtx_unlock(ip_mutex);
 }
 
 /*
  * Drain off all datagram fragments.
  */
 void
-ip_drain()
+ip_drain(void)
 {
        int     i;
 
+       lck_mtx_lock(ip_mutex);
        for (i = 0; i < IPREASS_NHASH; i++) {
                while (ipq[i].next != &ipq[i]) {
-                       ipstat.ips_fragdropped++;
+                       OSAddAtomic(ipq[i].next->ipq_nfrags, &ipstat.ips_fragdropped);
                        ip_freef(ipq[i].next);
                }
        }
+       lck_mtx_unlock(ip_mutex);
        in_rtqdrain();
 }
 
@@ -1300,20 +1798,26 @@ ip_drain()
  * Do option processing on a datagram,
  * possibly discarding it if bad options are encountered,
  * or forwarding it if source-routed.
+ * The pass argument is used when operating in the IPSTEALTH
+ * mode to tell what options to process:
+ * [LS]SRR (pass 0) or the others (pass 1).
+ * The reason for as many as two passes is that when doing IPSTEALTH,
+ * non-routing options should be processed only if the packet is for us.
  * Returns 1 if packet has been forwarded/freed,
  * 0 if the packet should be processed further.
  */
 static int
-ip_dooptions(m)
-       struct mbuf *m;
+ip_dooptions(struct mbuf *m, __unused int pass, struct sockaddr_in *next_hop)
 {
-       register struct ip *ip = mtod(m, struct ip *);
-       register u_char *cp;
-       register struct ip_timestamp *ipt;
-       register struct in_ifaddr *ia;
+       struct ip *ip = mtod(m, struct ip *);
+       u_char *cp;
+       struct ip_timestamp *ipt;
+       struct in_ifaddr *ia;
        int opt, optlen, cnt, off, code, type = ICMP_PARAMPROB, forward = 0;
        struct in_addr *sin, dst;
        n_time ntime;
+       struct sockaddr_in ipaddr = {
+           sizeof (ipaddr), AF_INET , 0 , { 0 }, { 0, } };
 
        dst = ip->ip_dst;
        cp = (u_char *)(ip + 1);
@@ -1376,6 +1880,10 @@ ip_dooptions(m)
                                 */
                                break;
                        }
+                       else {
+                               IFA_REMREF(&ia->ia_ifa);
+                               ia = NULL;
+                       }
                        off--;                  /* 0 origin */
                        if (off > optlen - (int)sizeof(struct in_addr)) {
                                /*
@@ -1389,15 +1897,16 @@ ip_dooptions(m)
 
                        if (!ip_dosourceroute) {
                                if (ipforwarding) {
-                                       char buf[16]; /* aaa.bbb.ccc.ddd\0 */
+                                       char buf[MAX_IPv4_STR_LEN];
+                                       char buf2[MAX_IPv4_STR_LEN];
                                        /*
                                         * Acting as a router, so generate ICMP
                                         */
 nosourcerouting:
-                                       strcpy(buf, inet_ntoa(ip->ip_dst));
-                                       log(LOG_WARNING, 
+                                       log(LOG_WARNING,
                                            "attempted source route from %s to %s\n",
-                                           inet_ntoa(ip->ip_src), buf);
+                                           inet_ntop(AF_INET, &ip->ip_src, buf, sizeof(buf)),
+                                           inet_ntop(AF_INET, &ip->ip_dst, buf2, sizeof(buf2)));
                                        type = ICMP_UNREACH;
                                        code = ICMP_UNREACH_SRCFAIL;
                                        goto bad;
@@ -1405,7 +1914,7 @@ nosourcerouting:
                                        /*
                                         * Not acting as a router, so silently drop.
                                         */
-                                       ipstat.ips_cantforward++;
+                                       OSAddAtomic(1, &ipstat.ips_cantforward);
                                        m_freem(m);
                                        return (1);
                                }
@@ -1420,18 +1929,24 @@ nosourcerouting:
                        if (opt == IPOPT_SSRR) {
 #define        INA     struct in_ifaddr *
 #define        SA      struct sockaddr *
-                           if ((ia = (INA)ifa_ifwithdstaddr((SA)&ipaddr)) == 0)
-                               ia = (INA)ifa_ifwithnet((SA)&ipaddr);
-                       } else
+                           if ((ia = (INA)ifa_ifwithdstaddr((SA)&ipaddr)) == 0) {
+                                       ia = (INA)ifa_ifwithnet((SA)&ipaddr);
+                               }
+                       } else {
                                ia = ip_rtaddr(ipaddr.sin_addr);
+                       }
                        if (ia == 0) {
                                type = ICMP_UNREACH;
                                code = ICMP_UNREACH_SRCFAIL;
                                goto bad;
                        }
                        ip->ip_dst = ipaddr.sin_addr;
+                       IFA_LOCK(&ia->ia_ifa);
                        (void)memcpy(cp + off, &(IA_SIN(ia)->sin_addr),
                            sizeof(struct in_addr));
+                       IFA_UNLOCK(&ia->ia_ifa);
+                       IFA_REMREF(&ia->ia_ifa);
+                       ia = NULL;
                        cp[IPOPT_OFFSET] += sizeof(struct in_addr);
                        /*
                         * Let ip_intr's mcast routing check handle mcast pkts
@@ -1460,14 +1975,19 @@ nosourcerouting:
                         * locate outgoing interface; if we're the destination,
                         * use the incoming interface (should be same).
                         */
-                       if ((ia = (INA)ifa_ifwithaddr((SA)&ipaddr)) == 0 &&
-                           (ia = ip_rtaddr(ipaddr.sin_addr)) == 0) {
-                               type = ICMP_UNREACH;
-                               code = ICMP_UNREACH_HOST;
-                               goto bad;
+                       if ((ia = (INA)ifa_ifwithaddr((SA)&ipaddr)) == 0) {
+                               if ((ia = ip_rtaddr(ipaddr.sin_addr)) == 0) {
+                                       type = ICMP_UNREACH;
+                                       code = ICMP_UNREACH_HOST;
+                                       goto bad;
+                               }
                        }
+                       IFA_LOCK(&ia->ia_ifa);
                        (void)memcpy(cp + off, &(IA_SIN(ia)->sin_addr),
                            sizeof(struct in_addr));
+                       IFA_UNLOCK(&ia->ia_ifa);
+                       IFA_REMREF(&ia->ia_ifa);
+                       ia = NULL;
                        cp[IPOPT_OFFSET] += sizeof(struct in_addr);
                        break;
 
@@ -1509,9 +2029,13 @@ nosourcerouting:
                                                            m->m_pkthdr.rcvif);
                                if (ia == 0)
                                        continue;
+                               IFA_LOCK(&ia->ia_ifa);
                                (void)memcpy(sin, &IA_SIN(ia)->sin_addr,
                                    sizeof(struct in_addr));
+                               IFA_UNLOCK(&ia->ia_ifa);
                                ipt->ipt_ptr += sizeof(struct in_addr);
+                               IFA_REMREF(&ia->ia_ifa);
+                               ia = NULL;
                                break;
 
                        case IPOPT_TS_PRESPEC:
@@ -1523,8 +2047,10 @@ nosourcerouting:
                                }
                                (void)memcpy(&ipaddr.sin_addr, sin,
                                    sizeof(struct in_addr));
-                               if (ifa_ifwithaddr((SA)&ipaddr) == 0)
+                               if ((ia = (struct in_ifaddr*)ifa_ifwithaddr((SA)&ipaddr)) == 0)
                                        continue;
+                               IFA_REMREF(&ia->ia_ifa);
+                               ia = NULL;
                                ipt->ipt_ptr += sizeof(struct in_addr);
                                break;
 
@@ -1541,14 +2067,14 @@ nosourcerouting:
                }
        }
        if (forward && ipforwarding) {
-               ip_forward(m, 1);
+               ip_forward(m, 1, next_hop);
                return (1);
        }
        return (0);
 bad:
        ip->ip_len -= IP_VHL_HL(ip->ip_vhl) << 2;   /* XXX icmp_error adds in hdr length */
        icmp_error(m, type, code, 0, 0);
-       ipstat.ips_badoptions++;
+       OSAddAtomic(1, &ipstat.ips_badoptions);
        return (1);
 }
 
@@ -1556,28 +2082,30 @@ bad:
  * Given address of next destination (final or next hop),
  * return internet address info of interface to be used to get there.
  */
-static struct in_ifaddr *
-ip_rtaddr(dst)
-        struct in_addr dst;
+struct in_ifaddr *
+ip_rtaddr(struct in_addr dst)
 {
-       register struct sockaddr_in *sin;
-
-       sin = (struct sockaddr_in *) &ipforward_rt.ro_dst;
-
-       if (ipforward_rt.ro_rt == 0 || dst.s_addr != sin->sin_addr.s_addr) {
-               if (ipforward_rt.ro_rt) {
-                       rtfree(ipforward_rt.ro_rt);
-                       ipforward_rt.ro_rt = 0;
-               }
-               sin->sin_family = AF_INET;
-               sin->sin_len = sizeof(*sin);
-               sin->sin_addr = dst;
-
-               rtalloc_ign(&ipforward_rt, RTF_PRCLONING);
-       }
-       if (ipforward_rt.ro_rt == 0)
-               return ((struct in_ifaddr *)0);
-       return ((struct in_ifaddr *) ipforward_rt.ro_rt->rt_ifa);
+       struct sockaddr_in *sin;
+       struct ifaddr *rt_ifa;
+       struct route ro;
+
+       bzero(&ro, sizeof (ro));
+       sin = (struct sockaddr_in *)&ro.ro_dst;
+       sin->sin_family = AF_INET;
+       sin->sin_len = sizeof (*sin);
+       sin->sin_addr = dst;
+
+       rtalloc_ign(&ro, RTF_PRCLONING);
+       if (ro.ro_rt == NULL)
+               return (NULL);
+
+       RT_LOCK(ro.ro_rt);
+       if ((rt_ifa = ro.ro_rt->rt_ifa) != NULL)
+               IFA_ADDREF(rt_ifa);
+       RT_UNLOCK(ro.ro_rt);
+       rtfree(ro.ro_rt);
+
+       return ((struct in_ifaddr *)rt_ifa);
 }
 
 /*
@@ -1585,9 +2113,7 @@ ip_rtaddr(dst)
  * to be picked up later by ip_srcroute if the receiver is interested.
  */
 void
-save_rte(option, dst)
-       u_char *option;
-       struct in_addr dst;
+save_rte(u_char *option, struct in_addr dst)
 {
        unsigned olen;
 
@@ -1609,10 +2135,10 @@ save_rte(option, dst)
  * The first hop is placed before the options, will be removed later.
  */
 struct mbuf *
-ip_srcroute()
+ip_srcroute(void)
 {
-       register struct in_addr *p, *q;
-       register struct mbuf *m;
+       struct in_addr *p, *q;
+       struct mbuf *m;
 
        if (ip_nhops == 0)
                return ((struct mbuf *)0);
@@ -1637,7 +2163,7 @@ ip_srcroute()
        *(mtod(m, struct in_addr *)) = *p--;
 #if DIAGNOSTIC
        if (ipprintfs)
-               printf(" hops %lx", (u_long)ntohl(mtod(m, struct in_addr *)->s_addr));
+               printf(" hops %lx", (u_int32_t)ntohl(mtod(m, struct in_addr *)->s_addr));
 #endif
 
        /*
@@ -1657,7 +2183,7 @@ ip_srcroute()
        while (p >= ip_srcrt.route) {
 #if DIAGNOSTIC
                if (ipprintfs)
-                       printf(" %lx", (u_long)ntohl(q->s_addr));
+                       printf(" %lx", (u_int32_t)ntohl(q->s_addr));
 #endif
                *q++ = *p--;
        }
@@ -1667,7 +2193,7 @@ ip_srcroute()
        *q = ip_srcrt.dst;
 #if DIAGNOSTIC
        if (ipprintfs)
-               printf(" %lx\n", (u_long)ntohl(q->s_addr));
+               printf(" %lx\n", (u_int32_t)ntohl(q->s_addr));
 #endif
        return (m);
 }
@@ -1680,13 +2206,11 @@ ip_srcroute()
  * XXX should be deleted; last arg currently ignored.
  */
 void
-ip_stripoptions(m, mopt)
-       register struct mbuf *m;
-       struct mbuf *mopt;
+ip_stripoptions(struct mbuf *m, __unused struct mbuf *mopt)
 {
-       register int i;
+       int i;
        struct ip *ip = mtod(m, struct ip *);
-       register caddr_t opts;
+       caddr_t opts;
        int olen;
 
        olen = (IP_VHL_HL(ip->ip_vhl) << 2) - sizeof (struct ip);
@@ -1702,12 +2226,82 @@ ip_stripoptions(m, mopt)
 u_char inetctlerrmap[PRC_NCMDS] = {
        0,              0,              0,              0,
        0,              EMSGSIZE,       EHOSTDOWN,      EHOSTUNREACH,
-       EHOSTUNREACH,   EHOSTUNREACH,   ECONNREFUSED,   ECONNREFUSED,
+       ENETUNREACH,    EHOSTUNREACH,   ECONNREFUSED,   ECONNREFUSED,
        EMSGSIZE,       EHOSTUNREACH,   0,              0,
        0,              0,              0,              0,
        ENOPROTOOPT,    ECONNREFUSED
 };
 
+static int
+sysctl_ipforwarding SYSCTL_HANDLER_ARGS
+{
+#pragma unused(arg1, arg2)
+       int i, was_ipforwarding = ipforwarding;
+
+       i = sysctl_handle_int(oidp, oidp->oid_arg1, oidp->oid_arg2, req);
+       if (i != 0 || req->newptr == USER_ADDR_NULL)
+               return (i);
+
+       if (was_ipforwarding && !ipforwarding) {
+               /* clean up IPv4 forwarding cached routes */
+               ifnet_head_lock_shared();
+               for (i = 0; i <= if_index; i++) {
+                       struct ifnet *ifp = ifindex2ifnet[i];
+                       if (ifp != NULL) {
+                               lck_mtx_lock(&ifp->if_cached_route_lock);
+                               if (ifp->if_fwd_route.ro_rt != NULL)
+                                       rtfree(ifp->if_fwd_route.ro_rt);
+                               bzero(&ifp->if_fwd_route,
+                                   sizeof (ifp->if_fwd_route));
+                               lck_mtx_unlock(&ifp->if_cached_route_lock);
+                       }
+               }
+               ifnet_head_done();
+       }
+
+       return (0);
+}
+
+/*
+ * Similar to inp_route_{copyout,copyin} routines except that these copy
+ * out the cached IPv4 forwarding route from struct ifnet instead of the
+ * inpcb.  See comments for those routines for explanations.
+ */
+static void
+ip_fwd_route_copyout(struct ifnet *ifp, struct route *dst)
+{
+       struct route *src = &ifp->if_fwd_route;
+
+       lck_mtx_lock_spin(&ifp->if_cached_route_lock);
+       lck_mtx_convert_spin(&ifp->if_cached_route_lock);
+
+       /* Minor sanity check */
+       if (src->ro_rt != NULL && rt_key(src->ro_rt)->sa_family != AF_INET)
+               panic("%s: wrong or corrupted route: %p", __func__, src);
+
+       route_copyout(dst, src, sizeof(*dst));
+
+       lck_mtx_unlock(&ifp->if_cached_route_lock);
+}
+
+static void
+ip_fwd_route_copyin(struct ifnet *ifp, struct route *src)
+{
+       struct route *dst = &ifp->if_fwd_route;
+
+       lck_mtx_lock_spin(&ifp->if_cached_route_lock);
+       lck_mtx_convert_spin(&ifp->if_cached_route_lock);
+
+       /* Minor sanity check */
+       if (src->ro_rt != NULL && rt_key(src->ro_rt)->sa_family != AF_INET)
+               panic("%s: wrong or corrupted route: %p", __func__, src);
+
+       if (ifp->if_fwd_cacheok)
+               route_copyin(src, dst, sizeof(*src));
+
+       lck_mtx_unlock(&ifp->if_cached_route_lock);
+}
+
 /*
  * Forward a packet.  If some error occurs return the sender
  * an icmp packet.  Note we can't always generate a meaningful
@@ -1723,32 +2317,46 @@ u_char inetctlerrmap[PRC_NCMDS] = {
  * via a source route.
  */
 static void
-ip_forward(m, srcrt)
-       struct mbuf *m;
-       int srcrt;
+ip_forward(struct mbuf *m, int srcrt, struct sockaddr_in *next_hop)
 {
-       register struct ip *ip = mtod(m, struct ip *);
-       register struct sockaddr_in *sin;
-       register struct rtentry *rt;
+#if !IPFIREWALL
+#pragma unused(next_hop)
+#endif
+       struct ip *ip = mtod(m, struct ip *);
+       struct sockaddr_in *sin;
+       struct rtentry *rt;
+       struct route fwd_rt;
        int error, type = 0, code = 0;
        struct mbuf *mcopy;
        n_long dest;
-       struct ifnet *destifp;
-#if IPSEC
-       struct ifnet dummyifp;
-#endif
+       struct in_addr pkt_dst;
+       u_int32_t nextmtu = 0;
+       struct ip_out_args ipoa = { IFSCOPE_NONE, 0 };
+       struct ifnet *ifp = m->m_pkthdr.rcvif;
+#if PF
+       struct pf_mtag *pf_mtag;
+#endif /* PF */
 
        dest = 0;
+#if IPFIREWALL
+       /*
+        * Cache the destination address of the packet; this may be
+        * changed by use of 'ipfw fwd'.
+        */
+       pkt_dst = next_hop ? next_hop->sin_addr : ip->ip_dst;
+#else
+       pkt_dst = ip->ip_dst;
+#endif
+
 #if DIAGNOSTIC
        if (ipprintfs)
                printf("forward: src %lx dst %lx ttl %x\n",
-                   (u_long)ip->ip_src.s_addr, (u_long)ip->ip_dst.s_addr,
+                   (u_int32_t)ip->ip_src.s_addr, (u_int32_t)pkt_dst.s_addr,
                    ip->ip_ttl);
 #endif
 
-
-       if (m->m_flags & (M_BCAST|M_MCAST) || in_canforward(ip->ip_dst) == 0) {
-               ipstat.ips_cantforward++;
+       if (m->m_flags & (M_BCAST|M_MCAST) || in_canforward(pkt_dst) == 0) {
+               OSAddAtomic(1, &ipstat.ips_cantforward);
                m_freem(m);
                return;
        }
@@ -1764,24 +2372,33 @@ ip_forward(m, srcrt)
        }
 #endif
 
-       sin = (struct sockaddr_in *)&ipforward_rt.ro_dst;
-       if ((rt = ipforward_rt.ro_rt) == 0 ||
-           ip->ip_dst.s_addr != sin->sin_addr.s_addr) {
-               if (ipforward_rt.ro_rt) {
-                       rtfree(ipforward_rt.ro_rt);
-                       ipforward_rt.ro_rt = 0;
+#if PF
+       pf_mtag = pf_find_mtag(m);
+       if (pf_mtag != NULL && pf_mtag->rtableid != IFSCOPE_NONE)
+               ipoa.ipoa_boundif = pf_mtag->rtableid;
+#endif /* PF */
+
+       ip_fwd_route_copyout(ifp, &fwd_rt);
+
+       sin = (struct sockaddr_in *)&fwd_rt.ro_dst;
+       if (fwd_rt.ro_rt == NULL ||
+           fwd_rt.ro_rt->generation_id != route_generation ||
+           pkt_dst.s_addr != sin->sin_addr.s_addr) {
+               if (fwd_rt.ro_rt != NULL) {
+                       rtfree(fwd_rt.ro_rt);
+                       fwd_rt.ro_rt = NULL;
                }
                sin->sin_family = AF_INET;
-               sin->sin_len = sizeof(*sin);
-               sin->sin_addr = ip->ip_dst;
+               sin->sin_len = sizeof (*sin);
+               sin->sin_addr = pkt_dst;
 
-               rtalloc_ign(&ipforward_rt, RTF_PRCLONING);
-               if (ipforward_rt.ro_rt == 0) {
+               rtalloc_scoped_ign(&fwd_rt, RTF_PRCLONING, ipoa.ipoa_boundif);
+               if (fwd_rt.ro_rt == NULL) {
                        icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_HOST, dest, 0);
-                       return;
+                       goto done;
                }
-               rt = ipforward_rt.ro_rt;
        }
+       rt = fwd_rt.ro_rt;
 
        /*
         * Save the IP header and at most 8 bytes of the payload,
@@ -1816,49 +2433,82 @@ ip_forward(m, srcrt)
         * Also, don't send redirect if forwarding using a default route
         * or a route modified by a redirect.
         */
-#define        satosin(sa)     ((struct sockaddr_in *)(sa))
+       RT_LOCK_SPIN(rt);
        if (rt->rt_ifp == m->m_pkthdr.rcvif &&
            (rt->rt_flags & (RTF_DYNAMIC|RTF_MODIFIED)) == 0 &&
            satosin(rt_key(rt))->sin_addr.s_addr != 0 &&
-           ipsendredirects && !srcrt) {
-#define        RTA(rt) ((struct in_ifaddr *)(rt->rt_ifa))
-               u_long src = ntohl(ip->ip_src.s_addr);
-
-               if (RTA(rt) &&
-                   (src & RTA(rt)->ia_subnetmask) == RTA(rt)->ia_subnet) {
-                   if (rt->rt_flags & RTF_GATEWAY)
-                       dest = satosin(rt->rt_gateway)->sin_addr.s_addr;
-                   else
-                       dest = ip->ip_dst.s_addr;
-                   /* Router requirements says to only send host redirects */
-                   type = ICMP_REDIRECT;
-                   code = ICMP_REDIRECT_HOST;
+           ipsendredirects && !srcrt && rt->rt_ifa != NULL) {
+               struct in_ifaddr *ia = (struct in_ifaddr *)rt->rt_ifa;
+               u_int32_t src = ntohl(ip->ip_src.s_addr);
+
+               /* Become a regular mutex */
+               RT_CONVERT_LOCK(rt);
+               IFA_LOCK_SPIN(&ia->ia_ifa);
+               if ((src & ia->ia_subnetmask) == ia->ia_subnet) {
+                       if (rt->rt_flags & RTF_GATEWAY)
+                               dest = satosin(rt->rt_gateway)->sin_addr.s_addr;
+                       else
+                               dest = pkt_dst.s_addr;
+                       /* Router requirements says to only send host redirects */
+                       type = ICMP_REDIRECT;
+                       code = ICMP_REDIRECT_HOST;
 #if DIAGNOSTIC
-                   if (ipprintfs)
-                       printf("redirect (%d) to %lx\n", code, (u_long)dest);
+                       if (ipprintfs)
+                               printf("redirect (%d) to %lx\n", code, (u_int32_t)dest);
 #endif
                }
+               IFA_UNLOCK(&ia->ia_ifa);
        }
+       RT_UNLOCK(rt);
+
+#if IPFIREWALL
+       if (next_hop) {
+               /* Pass IPFORWARD info if available */
+               struct m_tag *tag;
+               struct ip_fwd_tag       *ipfwd_tag;
+
+               tag = m_tag_create(KERNEL_MODULE_TAG_ID,
+                   KERNEL_TAG_TYPE_IPFORWARD,
+                   sizeof (*ipfwd_tag), M_NOWAIT, m);
+               if (tag == NULL) {
+                       error = ENOBUFS;
+                       m_freem(m);
+                       goto done;
+               }
+
+               ipfwd_tag = (struct ip_fwd_tag *)(tag+1);
+               ipfwd_tag->next_hop = next_hop;
+
+               m_tag_prepend(m, tag);
+       }
+#endif
+       error = ip_output_list(m, 0, NULL, &fwd_rt,
+           IP_FORWARDING | IP_OUTARGS, 0, &ipoa);
 
-       error = ip_output(m, (struct mbuf *)0, &ipforward_rt, 
-                         IP_FORWARDING, 0);
-       if (error)
-               ipstat.ips_cantforward++;
-       else {
-               ipstat.ips_forward++;
+       /* Refresh rt since the route could have changed while in IP */
+       rt = fwd_rt.ro_rt;
+
+       if (error) {
+               OSAddAtomic(1, &ipstat.ips_cantforward);
+       } else {
+               OSAddAtomic(1, &ipstat.ips_forward);
                if (type)
-                       ipstat.ips_redirectsent++;
+                       OSAddAtomic(1, &ipstat.ips_redirectsent);
                else {
                        if (mcopy) {
-                               ipflow_create(&ipforward_rt, mcopy);
+                               /*
+                                * If we didn't have to go thru ipflow and
+                                * the packet was successfully consumed by
+                                * ip_output, the mcopy is rather a waste;
+                                * this could be further optimized.
+                                */
                                m_freem(mcopy);
                        }
-                       return;
+                       goto done;
                }
        }
        if (mcopy == NULL)
-               return;
-       destifp = NULL;
+               goto done;
 
        switch (error) {
 
@@ -1879,8 +2529,12 @@ ip_forward(m, srcrt)
                type = ICMP_UNREACH;
                code = ICMP_UNREACH_NEEDFRAG;
 #ifndef IPSEC
-               if (ipforward_rt.ro_rt)
-                       destifp = ipforward_rt.ro_rt->rt_ifp;
+               if (rt != NULL) {
+                       RT_LOCK_SPIN(rt);
+                       if (rt->rt_ifp != NULL)
+                               nextmtu = rt->rt_ifp->if_mtu;
+                       RT_UNLOCK(rt);
+               }
 #else
                /*
                 * If the packet is routed over IPsec tunnel, tell the
@@ -1888,58 +2542,86 @@ ip_forward(m, srcrt)
                 *      tunnel MTU = if MTU - sizeof(IP) - ESP/AH hdrsiz
                 * XXX quickhack!!!
                 */
-               if (ipforward_rt.ro_rt) {
+               if (rt != NULL) {
                        struct secpolicy *sp = NULL;
                        int ipsecerror;
                        int ipsechdr;
                        struct route *ro;
 
+                       RT_LOCK_SPIN(rt);
+                       if (rt->rt_ifp != NULL)
+                               nextmtu = rt->rt_ifp->if_mtu;
+                       RT_UNLOCK(rt);
+
                        if (ipsec_bypass) {
-                               destifp = ipforward_rt.ro_rt->rt_ifp;
-                               ipstat.ips_cantfrag++;
+                               OSAddAtomic(1, &ipstat.ips_cantfrag);
                                break;
                        }
-
                        sp = ipsec4_getpolicybyaddr(mcopy,
                                                    IPSEC_DIR_OUTBOUND,
                                                    IP_FORWARDING,
                                                    &ipsecerror);
 
-                       if (sp == NULL)
-                               destifp = ipforward_rt.ro_rt->rt_ifp;
-                       else {
+                       if (sp != NULL) {
                                /* count IPsec header size */
-                               ipsechdr = ipsec4_hdrsiz(mcopy,
-                                                        IPSEC_DIR_OUTBOUND,
-                                                        NULL);
+                               ipsechdr = ipsec_hdrsiz(sp);
 
                                /*
                                 * find the correct route for outer IPv4
                                 * header, compute tunnel MTU.
-                                *
-                                * XXX BUG ALERT
-                                * The "dummyifp" code relies upon the fact
-                                * that icmp_error() touches only ifp->if_mtu.
                                 */
-                               /*XXX*/
-                               destifp = NULL;
-                               if (sp->req != NULL
-                                && sp->req->sav != NULL
-                                && sp->req->sav->sah != NULL) {
-                                       ro = &sp->req->sav->sah->sa_route;
-                                       if (ro->ro_rt && ro->ro_rt->rt_ifp) {
-                                               dummyifp.if_mtu =
-                                                   ro->ro_rt->rt_ifp->if_mtu;
-                                               dummyifp.if_mtu -= ipsechdr;
-                                               destifp = &dummyifp;
+                               nextmtu = 0;
+
+                               if (sp->req != NULL) {
+                                       if (sp->req->saidx.mode == IPSEC_MODE_TUNNEL) {
+                                               struct secasindex saidx;
+                                               struct ip *ipm;
+                                               struct secasvar *sav;
+
+                                               ipm = mtod(mcopy, struct ip *);
+                                               bcopy(&sp->req->saidx, &saidx, sizeof(saidx));
+                                               saidx.mode = sp->req->saidx.mode;
+                                               saidx.reqid = sp->req->saidx.reqid;
+                                               sin = (struct sockaddr_in *)&saidx.src;
+                                               if (sin->sin_len == 0) {
+                                                       sin->sin_len = sizeof(*sin);
+                                                       sin->sin_family = AF_INET;
+                                                       sin->sin_port = IPSEC_PORT_ANY;
+                                                       bcopy(&ipm->ip_src, &sin->sin_addr,
+                                                               sizeof(sin->sin_addr));
+                                               }
+                                               sin = (struct sockaddr_in *)&saidx.dst;
+                                               if (sin->sin_len == 0) {
+                                                       sin->sin_len = sizeof(*sin);
+                                                       sin->sin_family = AF_INET;
+                                                       sin->sin_port = IPSEC_PORT_ANY;
+                                                       bcopy(&ipm->ip_dst, &sin->sin_addr,
+                                                               sizeof(sin->sin_addr));
+                                               }
+                                               sav = key_allocsa_policy(&saidx);
+                                               if (sav != NULL) {
+                                                       lck_mtx_lock(sadb_mutex);
+                                                       if (sav->sah != NULL) {
+                                                               ro = &sav->sah->sa_route;
+                                                               if (ro->ro_rt != NULL) {
+                                                                       RT_LOCK(ro->ro_rt);
+                                                                       if (ro->ro_rt->rt_ifp != NULL) {
+                                                                               nextmtu = ro->ro_rt->rt_ifp->if_mtu;
+                                                                               nextmtu -= ipsechdr;
+                                                                       }
+                                                                       RT_UNLOCK(ro->ro_rt);
+                                                               }
+                                                       }
+                                                       key_freesav(sav, KEY_SADB_LOCKED);
+                                                       lck_mtx_unlock(sadb_mutex);
+                                               }
                                        }
                                }
-
-                               key_freesp(sp);
+                               key_freesp(sp, KEY_SADB_UNLOCKED);
                        }
                }
 #endif /*IPSEC*/
-               ipstat.ips_cantfrag++;
+               OSAddAtomic(1, &ipstat.ips_cantfrag);
                break;
 
        case ENOBUFS:
@@ -1949,32 +2631,49 @@ ip_forward(m, srcrt)
 
        case EACCES:                    /* ipfw denied packet */
                m_freem(mcopy);
-               return;
+               goto done;
        }
-       icmp_error(mcopy, type, code, dest, destifp);
+
+       icmp_error(mcopy, type, code, dest, nextmtu);
+done:
+       ip_fwd_route_copyin(ifp, &fwd_rt);
 }
 
-void
-ip_savecontrol(inp, mp, ip, m)
-       register struct inpcb *inp;
-       register struct mbuf **mp;
-       register struct ip *ip;
-       register struct mbuf *m;
+int
+ip_savecontrol(
+       struct inpcb *inp,
+       struct mbuf **mp,
+       struct ip *ip,
+       struct mbuf *m)
 {
+       *mp = NULL;
        if (inp->inp_socket->so_options & SO_TIMESTAMP) {
                struct timeval tv;
 
                microtime(&tv);
-               *mp = sbcreatecontrol((caddr_t) &tv, sizeof(tv),
-                       SCM_TIMESTAMP, SOL_SOCKET);
-               if (*mp)
-                       mp = &(*mp)->m_next;
+               mp = sbcreatecontrol_mbuf((caddr_t) &tv, sizeof(tv),
+                       SCM_TIMESTAMP, SOL_SOCKET, mp);
+               if (*mp == NULL) {
+                       goto no_mbufs;
+               }
        }
+       if ((inp->inp_socket->so_options & SO_TIMESTAMP_MONOTONIC) != 0) {
+               uint64_t time;
+
+               time = mach_absolute_time();
+               mp = sbcreatecontrol_mbuf((caddr_t) &time, sizeof(time),
+                       SCM_TIMESTAMP_MONOTONIC, SOL_SOCKET, mp);
+               
+               if (*mp == NULL) {
+                       goto no_mbufs;
+               }
+       } 
        if (inp->inp_flags & INP_RECVDSTADDR) {
-               *mp = sbcreatecontrol((caddr_t) &ip->ip_dst,
-                   sizeof(struct in_addr), IP_RECVDSTADDR, IPPROTO_IP);
-               if (*mp)
-                       mp = &(*mp)->m_next;
+               mp = sbcreatecontrol_mbuf((caddr_t) &ip->ip_dst,
+                       sizeof(struct in_addr), IP_RECVDSTADDR, IPPROTO_IP, mp);
+               if (*mp == NULL) {
+                       goto no_mbufs;
+               }
        }
 #ifdef notyet
        /* XXX
@@ -1983,17 +2682,19 @@ ip_savecontrol(inp, mp, ip, m)
         */
        /* options were tossed already */
        if (inp->inp_flags & INP_RECVOPTS) {
-               *mp = sbcreatecontrol((caddr_t) opts_deleted_above,
-                   sizeof(struct in_addr), IP_RECVOPTS, IPPROTO_IP);
-               if (*mp)
-                       mp = &(*mp)->m_next;
+               mp = sbcreatecontrol_mbuf((caddr_t) opts_deleted_above,
+                       sizeof(struct in_addr), IP_RECVOPTS, IPPROTO_IP, mp);
+               if (*mp == NULL) {
+                       goto no_mbufs;
+               }
        }
        /* ip_srcroute doesn't do what we want here, need to fix */
        if (inp->inp_flags & INP_RECVRETOPTS) {
-               *mp = sbcreatecontrol((caddr_t) ip_srcroute(),
-                   sizeof(struct in_addr), IP_RECVRETOPTS, IPPROTO_IP);
-               if (*mp)
-                       mp = &(*mp)->m_next;
+               mp = sbcreatecontrol_mbuf((caddr_t) ip_srcroute(),
+                       sizeof(struct in_addr), IP_RECVRETOPTS, IPPROTO_IP, mp);
+               if (*mp == NULL) {
+                       goto no_mbufs;
+               }
        }
 #endif
        if (inp->inp_flags & INP_RECVIF) {
@@ -2005,31 +2706,75 @@ ip_savecontrol(inp, mp, ip, m)
                struct sockaddr_dl *sdp;
                struct sockaddr_dl *sdl2 = &sdlbuf.sdl;
 
-               if (((ifp = m->m_pkthdr.rcvif)) 
-               && ( ifp->if_index && (ifp->if_index <= if_index))) {
-                       sdp = (struct sockaddr_dl *)(ifnet_addrs
-                                       [ifp->if_index - 1]->ifa_addr);
+               ifnet_head_lock_shared();
+               if ((ifp = m->m_pkthdr.rcvif) != NULL &&
+                   ifp->if_index && (ifp->if_index <= if_index)) {
+                       struct ifaddr *ifa = ifnet_addrs[ifp->if_index - 1];
+
+                       if (!ifa || !ifa->ifa_addr)
+                               goto makedummy;
+
+                       IFA_LOCK_SPIN(ifa);
+                       sdp = (struct sockaddr_dl *)ifa->ifa_addr;
                        /*
                         * Change our mind and don't try copy.
                         */
-                       if ((sdp->sdl_family != AF_LINK)
-                       || (sdp->sdl_len > sizeof(sdlbuf))) {
+                       if ((sdp->sdl_family != AF_LINK) ||
+                           (sdp->sdl_len > sizeof(sdlbuf))) {
+                               IFA_UNLOCK(ifa);
                                goto makedummy;
                        }
                        bcopy(sdp, sdl2, sdp->sdl_len);
+                       IFA_UNLOCK(ifa);
                } else {
-makedummy:     
+makedummy:
                        sdl2->sdl_len
                                = offsetof(struct sockaddr_dl, sdl_data[0]);
                        sdl2->sdl_family = AF_LINK;
                        sdl2->sdl_index = 0;
                        sdl2->sdl_nlen = sdl2->sdl_alen = sdl2->sdl_slen = 0;
                }
-               *mp = sbcreatecontrol((caddr_t) sdl2, sdl2->sdl_len,
-                       IP_RECVIF, IPPROTO_IP);
-               if (*mp)
-                       mp = &(*mp)->m_next;
+               ifnet_head_done();
+               mp = sbcreatecontrol_mbuf((caddr_t) sdl2, sdl2->sdl_len,
+                       IP_RECVIF, IPPROTO_IP, mp);
+               if (*mp == NULL) {
+                       goto no_mbufs;
+               }
+       }
+       if (inp->inp_flags & INP_RECVTTL) {
+               mp = sbcreatecontrol_mbuf((caddr_t)&ip->ip_ttl, sizeof(ip->ip_ttl), 
+                       IP_RECVTTL, IPPROTO_IP, mp);
+               if (*mp == NULL) {
+                       goto no_mbufs;
+               }
+       }
+       if ((inp->inp_socket->so_flags & SOF_RECV_TRAFFIC_CLASS) != 0) {
+               int tc = m->m_pkthdr.prio;
+               
+               mp = sbcreatecontrol_mbuf((caddr_t) &tc, sizeof(tc),
+                       SO_TRAFFIC_CLASS, SOL_SOCKET, mp);
+               if (*mp == NULL) {
+                       goto no_mbufs;
+               }
        }
+       if (inp->inp_flags & INP_PKTINFO) {
+               struct in_pktinfo pi;
+
+               bzero(&pi, sizeof(struct in_pktinfo));
+               bcopy(&ip->ip_dst, &pi.ipi_addr, sizeof(struct in_addr));
+               pi.ipi_ifindex = (m && m->m_pkthdr.rcvif) ? m->m_pkthdr.rcvif->if_index : 0;
+               
+               mp = sbcreatecontrol_mbuf((caddr_t)&pi, sizeof(struct in_pktinfo), 
+                       IP_RECVPKTINFO, IPPROTO_IP, mp);
+               if (*mp == NULL) {
+                       goto no_mbufs;
+               }
+       }
+       return 0;
+
+no_mbufs:
+       ipstat.ips_pktdropcntrl++;
+       return ENOBUFS;
 }
 
 int