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bsd/netinet/ip_input.c xnu-12377.121.6 xnu-792
--- xnu/xnu-12377.121.6/bsd/netinet/ip_input.c
+++ xnu/xnu-792/bsd/netinet/ip_input.c
@@ -1,29 +1,23 @@
 /*
- * Copyright (c) 2000-2021 Apple Inc. All rights reserved.
+ * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
  *
- * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
- *
- * This file contains Original Code and/or Modifications of Original Code
- * as defined in and that are subject to the Apple Public Source License
- * Version 2.0 (the 'License'). You may not use this file except in
- * compliance with the License. The rights granted to you under the License
- * may not be used to create, or enable the creation or redistribution of,
- * unlawful or unlicensed copies of an Apple operating system, or to
- * circumvent, violate, or enable the circumvention or violation of, any
- * terms of an Apple operating system software license agreement.
- *
- * 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
+ * @APPLE_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 Original Code and all software distributed under the License are
+ * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
- * Please see the License for the specific language governing rights and
- * limitations under the License.
- *
- * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
+ * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
+ * License for the specific language governing rights and limitations
+ * under the License.
+ * 
+ * @APPLE_LICENSE_HEADER_END@
  */
 /*
  * Copyright (c) 1982, 1986, 1988, 1993
@@ -58,15 +52,10 @@
  * SUCH DAMAGE.
  *
  *	@(#)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
+
+#define	_IP_VHL
 
 #include <sys/param.h>
 #include <sys/systm.h>
@@ -79,297 +68,198 @@
 #include <sys/kernel.h>
 #include <sys/syslog.h>
 #include <sys/sysctl.h>
-#include <sys/mcache.h>
-#include <sys/socketvar.h>
-#include <sys/kdebug.h>
-#include <mach/mach_time.h>
-#include <mach/sdt.h>
-
-#include <machine/endian.h>
-#include <dev/random/randomdev.h>
 
 #include <kern/queue.h>
 #include <kern/locks.h>
-#include <libkern/OSAtomic.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/kpi_protocol.h>
-#include <net/ntstat.h>
-#include <net/dlil.h>
-#include <net/classq/classq.h>
-#include <net/net_perf.h>
-#include <net/init.h>
-#if PF
-#include <net/pfvar.h>
-#endif /* PF */
-#include <net/if_ports_used.h>
-#include <net/droptap.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 <netinet/ip_icmp.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>
 
-#if DUMMYNET
-#include <netinet/ip_dummynet.h>
-#endif /* DUMMYNET */
+#include <sys/kdebug.h>
+
+#define DBG_LAYER_BEG		NETDBG_CODE(DBG_NETIP, 0)
+#define DBG_LAYER_END		NETDBG_CODE(DBG_NETIP, 2)
+#define DBG_FNC_IP_INPUT	NETDBG_CODE(DBG_NETIP, (2 << 8))
+
 
 #if IPSEC
 #include <netinet6/ipsec.h>
 #include <netkey/key.h>
-#endif /* IPSEC */
-
-#include <net/sockaddr_utils.h>
-
-#include <os/log.h>
-
-extern void log_hexdump(os_log_t log_handle, void *__sized_by(len) data, size_t len);
-
-extern struct inpcbinfo ripcbinfo;
-
-#define DBG_LAYER_BEG           NETDBG_CODE(DBG_NETIP, 0)
-#define DBG_LAYER_END           NETDBG_CODE(DBG_NETIP, 2)
-#define DBG_FNC_IP_INPUT        NETDBG_CODE(DBG_NETIP, (2 << 8))
+#endif
+
+#include "faith.h"
+#if defined(NFAITH) && NFAITH > 0
+#include <net/if_types.h>
+#endif
+
+#if DUMMYNET
+#include <netinet/ip_dummynet.h>
+#endif
 
 #if IPSEC
 extern int ipsec_bypass;
-#endif /* IPSEC */
-
-MBUFQ_HEAD(fq_head);
-
-static int frag_timeout_run;            /* frag timer is scheduled to run */
-static void frag_timeout(void *);
-static void frag_sched_timeout(void);
-
-static struct ipq *ipq_alloc(void);
-static void ipq_free(struct ipq *);
-static void ipq_updateparams(void);
-static void ip_input_second_pass(struct mbuf *, struct ifnet *,
-    int, int, struct ip_fw_in_args *);
-
-static LCK_GRP_DECLARE(ipqlock_grp, "ipqlock");
-static LCK_MTX_DECLARE(ipqlock, &ipqlock_grp);
-
+extern lck_mtx_t *sadb_mutex;
+#endif
+
+int rsvp_on = 0;
+static int ip_rsvp_on;
+struct socket *ip_rsvpd;
+
+int	ipforwarding = 0;
+SYSCTL_INT(_net_inet_ip, IPCTL_FORWARDING, forwarding, CTLFLAG_RW,
+    &ipforwarding, 0, "Enable IP forwarding between interfaces");
+
+static int	ipsendredirects = 1; /* XXX */
+SYSCTL_INT(_net_inet_ip, IPCTL_SENDREDIRECTS, redirect, CTLFLAG_RW,
+    &ipsendredirects, 0, "Enable sending IP redirects");
+
+int	ip_defttl = IPDEFTTL;
+SYSCTL_INT(_net_inet_ip, IPCTL_DEFTTL, ttl, CTLFLAG_RW,
+    &ip_defttl, 0, "Maximum TTL on IP packets");
+
+static int	ip_dosourceroute = 0;
+SYSCTL_INT(_net_inet_ip, IPCTL_SOURCEROUTE, sourceroute, CTLFLAG_RW,
+    &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, 
+    "Enable accepting source routed IP packets");
+
+static int	ip_keepfaith = 0;
+SYSCTL_INT(_net_inet_ip, IPCTL_KEEPFAITH, keepfaith, CTLFLAG_RW,
+	&ip_keepfaith,	0,
+	"Enable packet capture for FAITH IPv4->IPv6 translater daemon");
+
+static int	nipq = 0;	/* total # of reass queues */
+static int	maxnipq;
+SYSCTL_INT(_net_inet_ip, OID_AUTO, maxfragpackets, CTLFLAG_RW,
+	&maxnipq, 0,
+	"Maximum number of IPv4 fragment reassembly queue entries");
+
+static int    maxfragsperpacket;
+SYSCTL_INT(_net_inet_ip, OID_AUTO, maxfragsperpacket, CTLFLAG_RW,
+	&maxfragsperpacket, 0,
+	"Maximum number of IPv4 fragments allowed per packet");
+
+static int    maxfrags;
+SYSCTL_INT(_net_inet_ip, OID_AUTO, maxfrags, CTLFLAG_RW,
+	&maxfrags, 0, "Maximum number of IPv4 fragments allowed");
+
+static int    currentfrags = 0;
+
+/*
+ * XXX - Setting ip_checkinterface mostly implements the receive side of
+ * the Strong ES model described in RFC 1122, but since the routing table
+ * and transmit implementation do not implement the Strong ES model,
+ * setting this to 1 results in an odd hybrid.
+ *
+ * XXX - ip_checkinterface currently must be disabled if you use ipnat
+ * to translate the destination address to another local interface.
+ *
+ * XXX - ip_checkinterface must be disabled if you add IP aliases
+ * to the loopback interface instead of the interface where the
+ * packets for those addresses are received.
+ */
+static int	ip_checkinterface = 0;
+SYSCTL_INT(_net_inet_ip, OID_AUTO, check_interface, CTLFLAG_RW,
+    &ip_checkinterface, 0, "Verify packet arrives on correct interface");
+
+#if DIAGNOSTIC
+static int	ipprintfs = 0;
+#endif
+
+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 */
+struct	ifqueue ipintrq;
+SYSCTL_INT(_net_inet_ip, IPCTL_INTRQMAXLEN, intr_queue_maxlen, CTLFLAG_RW,
+    &ipintrq.ifq_maxlen, 0, "Maximum size of the IP input queue");
+SYSCTL_INT(_net_inet_ip, IPCTL_INTRQDROPS, intr_queue_drops, CTLFLAG_RD,
+    &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,
+    &ipstat, ipstat, "IP statistics (struct ipstat, netinet/ip_var.h)");
 
 /* Packet reassembly stuff */
 #define IPREASS_NHASH_LOG2      6
 #define IPREASS_NHASH           (1 << IPREASS_NHASH_LOG2)
 #define IPREASS_HMASK           (IPREASS_NHASH - 1)
-#define IPREASS_HASH(x, y) \
+#define IPREASS_HASH(x,y) \
 	(((((x) & 0xF) | ((((x) >> 8) & 0xF) << 4)) ^ (y)) & IPREASS_HMASK)
 
-/* IP fragment reassembly queues (protected by ipqlock) */
-static TAILQ_HEAD(ipqhead, ipq) ipq[IPREASS_NHASH]; /* ip reassembly queues */
-static int maxnipq;                     /* max packets in reass queues */
-static u_int32_t maxfragsperpacket;     /* max frags/packet in reass queues */
-static u_int32_t nipq;                  /* # of packets in reass queues */
-static u_int32_t ipq_limit;             /* ipq allocation limit */
-static u_int32_t ipq_count;             /* current # of allocated ipq's */
-
-static int sysctl_ipforwarding SYSCTL_HANDLER_ARGS;
-static int sysctl_maxnipq SYSCTL_HANDLER_ARGS;
-static int sysctl_maxfragsperpacket SYSCTL_HANDLER_ARGS;
-
-#if (DEBUG || DEVELOPMENT)
-static int sysctl_reset_ip_input_stats SYSCTL_HANDLER_ARGS;
-static int sysctl_ip_input_measure_bins SYSCTL_HANDLER_ARGS;
-static int sysctl_ip_input_getperf SYSCTL_HANDLER_ARGS;
-#endif /* (DEBUG || DEVELOPMENT) */
-
-int ipforwarding = 0;
-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 | CTLFLAG_LOCKED, &ipsendredirects, 0,
-    "Enable sending IP redirects");
-
-int ip_defttl = IPDEFTTL;
-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 | 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 | CTLFLAG_LOCKED, &ip_acceptsourceroute, 0,
-    "Enable accepting source routed IP packets");
-
-static int ip_sendsourcequench = 0;
-SYSCTL_INT(_net_inet_ip, OID_AUTO, sendsourcequench,
-    CTLFLAG_RW | CTLFLAG_LOCKED, &ip_sendsourcequench, 0,
-    "Enable the transmission of source quench packets");
-
-SYSCTL_PROC(_net_inet_ip, OID_AUTO, maxfragpackets,
-    CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_LOCKED, &maxnipq, 0, sysctl_maxnipq,
-    "I", "Maximum number of IPv4 fragment reassembly queue entries");
-
-SYSCTL_UINT(_net_inet_ip, OID_AUTO, fragpackets, CTLFLAG_RD | CTLFLAG_LOCKED,
-    &nipq, 0, "Current number of IPv4 fragment reassembly queue entries");
-
-SYSCTL_PROC(_net_inet_ip, OID_AUTO, maxfragsperpacket,
-    CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_LOCKED, &maxfragsperpacket, 0,
-    sysctl_maxfragsperpacket, "I",
-    "Maximum number of IPv4 fragments allowed per packet");
-
-static uint32_t ip_adj_clear_hwcksum = 0;
-SYSCTL_UINT(_net_inet_ip, OID_AUTO, adj_clear_hwcksum,
-    CTLFLAG_RW | CTLFLAG_LOCKED, &ip_adj_clear_hwcksum, 0,
-    "Invalidate hwcksum info when adjusting length");
-
-static uint32_t ip_adj_partial_sum = 1;
-SYSCTL_UINT(_net_inet_ip, OID_AUTO, adj_partial_sum,
-    CTLFLAG_RW | CTLFLAG_LOCKED, &ip_adj_partial_sum, 0,
-    "Perform partial sum adjustment of trailing bytes at IP layer");
-
-/*
- * ip_checkinterface controls the receive side of the models for multihoming
- * that are discussed in RFC 1122.
- *
- * ip_checkinterface values are:
- *  IP_CHECKINTERFACE_WEAK_ES:
- *	This corresponds to the Weak End-System model where incoming packets from
- *	any interface are accepted provided the destination address of the incoming packet
- *	is assigned to some interface.
- *
- *  IP_CHECKINTERFACE_HYBRID_ES:
- *	The Hybrid End-System model use the Strong End-System for tunnel interfaces
- *	(ipsec and utun) and the weak End-System model for other interfaces families.
- *	This prevents a rogue middle box to probe for signs of TCP connections
- *	that use the tunnel interface.
- *
- *  IP_CHECKINTERFACE_STRONG_ES:
- *	The Strong model model requires the packet arrived on an interface that
- *	is assigned the destination address of the packet.
- *
- * Since the routing table and transmit implementation do not implement the Strong ES model,
- * setting this to a value different from IP_CHECKINTERFACE_WEAK_ES may lead to unexpected results.
- *
- * When forwarding is enabled, the system reverts to the Weak ES model as a router
- * is expected by design to receive packets from several interfaces to the same address.
- *
- * XXX - ip_checkinterface currently must be set to IP_CHECKINTERFACE_WEAK_ES if you use ipnat
- * to translate the destination address to another local interface.
- *
- * XXX - ip_checkinterface must be set to IP_CHECKINTERFACE_WEAK_ES if you add IP aliases
- * to the loopback interface instead of the interface where the
- * packets for those addresses are received.
- */
-#define IP_CHECKINTERFACE_WEAK_ES       0
-#define IP_CHECKINTERFACE_HYBRID_ES     1
-#define IP_CHECKINTERFACE_STRONG_ES     2
-
-static int ip_checkinterface = IP_CHECKINTERFACE_HYBRID_ES;
-
-static int sysctl_ip_checkinterface SYSCTL_HANDLER_ARGS;
-SYSCTL_PROC(_net_inet_ip, OID_AUTO, check_interface,
-    CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_LOCKED,
-    0, 0, sysctl_ip_checkinterface, "I", "Verify packet arrives on correct interface");
-
-#if (DEBUG || DEVELOPMENT)
-#define IP_CHECK_IF_DEBUG 1
-#else
-#define IP_CHECK_IF_DEBUG 0
-#endif /* (DEBUG || DEVELOPMENT) */
-static int ip_checkinterface_debug = IP_CHECK_IF_DEBUG;
-SYSCTL_INT(_net_inet_ip, OID_AUTO, checkinterface_debug, CTLFLAG_RW | CTLFLAG_LOCKED,
-    &ip_checkinterface_debug, IP_CHECK_IF_DEBUG, "");
-
-static int ip_chainsz = 6;
-SYSCTL_INT(_net_inet_ip, OID_AUTO, rx_chainsz, CTLFLAG_RW | CTLFLAG_LOCKED,
-    &ip_chainsz, 1, "IP receive side max chaining");
-
-#if (DEBUG || DEVELOPMENT)
-static int ip_input_measure = 0;
-SYSCTL_PROC(_net_inet_ip, OID_AUTO, input_perf,
-    CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_LOCKED,
-    &ip_input_measure, 0, sysctl_reset_ip_input_stats, "I", "Do time measurement");
-
-static uint64_t ip_input_measure_bins = 0;
-SYSCTL_PROC(_net_inet_ip, OID_AUTO, input_perf_bins,
-    CTLTYPE_QUAD | CTLFLAG_RW | CTLFLAG_LOCKED, &ip_input_measure_bins, 0,
-    sysctl_ip_input_measure_bins, "I",
-    "bins for chaining performance data histogram");
-
-static net_perf_t net_perf;
-SYSCTL_PROC(_net_inet_ip, OID_AUTO, input_perf_data,
-    CTLTYPE_STRUCT | CTLFLAG_RD | CTLFLAG_LOCKED,
-    0, 0, sysctl_ip_input_getperf, "S,net_perf",
-    "IP input performance data (struct net_perf, net/net_perf.h)");
-#endif /* (DEBUG || DEVELOPMENT) */
-
-#if DIAGNOSTIC
-static int ipprintfs = 0;
-#endif
-
-struct protosw *ip_protox[IPPROTO_MAX];
-
-static LCK_GRP_DECLARE(in_ifaddr_rwlock_grp, "in_ifaddr_rwlock");
-LCK_RW_DECLARE(in_ifaddr_rwlock, &in_ifaddr_rwlock_grp);
-
-#define INADDR_NHASH    61
-static uint32_t inaddr_nhash;                  /* hash table size */
-static uint32_t inaddr_hashp;                  /* next largest prime */
-
-/* Protected by in_ifaddr_rwlock */
-struct in_ifaddrhead in_ifaddrhead;     /* first inet address */
-static struct in_ifaddrhashhead *__counted_by(inaddr_nhash) in_ifaddrhashtbl = NULL;  /* inet addr hash table  */
-
-static int ip_getstat SYSCTL_HANDLER_ARGS;
-struct ipstat ipstat;
-SYSCTL_PROC(_net_inet_ip, IPCTL_STATS, stats,
-    CTLTYPE_STRUCT | CTLFLAG_RD | CTLFLAG_LOCKED,
-    0, 0, ip_getstat, "S,ipstat",
-    "IP statistics (struct ipstat, netinet/ip_var.h)");
+static struct ipq ipq[IPREASS_NHASH];
+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 | CTLFLAG_LOCKED,
+SYSCTL_INT(_net_inet_ip, IPCTL_DEFMTU, mtu, CTLFLAG_RW,
     &ip_mtu, 0, "Default MTU");
-#endif /* IPCTL_DEFMTU */
+#endif
 
 #if IPSTEALTH
-static int      ipstealth = 0;
-SYSCTL_INT(_net_inet_ip, OID_AUTO, stealth, CTLFLAG_RW | CTLFLAG_LOCKED,
+static int	ipstealth = 0;
+SYSCTL_INT(_net_inet_ip, OID_AUTO, stealth, CTLFLAG_RW,
     &ipstealth, 0, "");
-#endif /* IPSTEALTH */
+#endif
+
+
+/* Firewall hooks */
+ip_fw_chk_t *ip_fw_chk_ptr;
+int fw_enable = 1 ;
+int fw_one_pass = 1;
 
 #if DUMMYNET
 ip_dn_io_t *ip_dn_io_ptr;
-#endif /* DUMMYNET */
-
-SYSCTL_NODE(_net_inet_ip, OID_AUTO, linklocal,
-    CTLFLAG_RW | CTLFLAG_LOCKED, 0, "link local");
+#endif
+
+int (*fr_checkp)(struct ip *, int, struct ifnet *, int, struct mbuf **) = NULL;
+
+SYSCTL_NODE(_net_inet_ip, OID_AUTO, linklocal, CTLFLAG_RW, 0, "link local");
 
 struct ip_linklocal_stat ip_linklocal_stat;
-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 | CTLFLAG_LOCKED, 0, "link local input");
+SYSCTL_STRUCT(_net_inet_ip_linklocal, OID_AUTO, stat, CTLFLAG_RD,
+        &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");
 
 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");
+SYSCTL_INT(_net_inet_ip_linklocal_in, OID_AUTO, allowbadttl, CTLFLAG_RW,
+        &ip_linklocal_in_allowbadttl, 0,
+        "Allow incoming link local packets with TTL less than 255");
 
 
 /*
@@ -379,835 +269,371 @@
  * maintenance when the remote end is on a network that is not known
  * to us.
  */
-static int      ip_nhops = 0;
-static  struct ip_srcrt {
-	struct  in_addr dst;                    /* final destination */
-	char    nop;                            /* one NOP to align */
-	char    srcopt[IPOPT_OFFSET + 1];       /* OPTVAL, OLEN and OFFSET */
-	struct  in_addr route[MAX_IPOPTLEN / sizeof(struct in_addr)];
+static int	ip_nhops = 0;
+static	struct ip_srcrt {
+	struct	in_addr dst;			/* final destination */
+	char	nop;				/* one NOP to align */
+	char	srcopt[IPOPT_OFFSET + 1];	/* OPTVAL, OLEN and OFFSET */
+	struct	in_addr route[MAX_IPOPTLEN/sizeof(struct in_addr)];
 } ip_srcrt;
 
-static void in_ifaddrhashtbl_init(void);
-static void save_rte(u_char *__indexable, 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 frag_freef(struct ipqhead *, struct ipq *, drop_reason_t);
-static struct mbuf *ip_reass(struct mbuf *);
-static void ip_fwd_route_copyout(struct ifnet *, struct route *);
-static void ip_fwd_route_copyin(struct ifnet *, struct route *);
-static inline u_short ip_cksum(struct mbuf *, int);
-
-/*
- * On platforms which require strict alignment (currently for anything but
- * i386 or x86_64 or arm64), check if the IP header pointer is 32-bit aligned; if not,
- * copy the contents of the mbuf chain into a new chain, and free the original
- * one.  Create some head room in the first mbuf of the new chain, in case
- * it's needed later on.
- */
-#if defined(__i386__) || defined(__x86_64__) || defined(__arm64__)
-#define IP_HDR_ALIGNMENT_FIXUP(_m, _ifp, _action) do { } while (0)
-#else /* !__i386__ && !__x86_64__ && !__arm64__ */
-#define IP_HDR_ALIGNMENT_FIXUP(_m, _ifp, _action) do {                  \
-	if (!IP_HDR_ALIGNED_P(mtod(_m, caddr_t))) {                     \
-	        struct mbuf *_n;                                        \
-	        struct ifnet *__ifp = (_ifp);                           \
-	        os_atomic_inc(&(__ifp)->if_alignerrs, relaxed);         \
-	        if (((_m)->m_flags & M_PKTHDR) &&                       \
-	            (_m)->m_pkthdr.pkt_hdr != NULL)                     \
-	                (_m)->m_pkthdr.pkt_hdr = NULL;                  \
-	        _n = m_defrag_offset(_m, max_linkhdr, M_NOWAIT);        \
-	        if (_n == NULL) {                                       \
-	                os_atomic_inc(&ipstat.ips_toosmall, relaxed);   \
-	                m_drop(_m, DROPTAP_FLAG_DIR_IN | DROPTAP_FLAG_L2_MISSING, DROP_REASON_IP_TOO_SMALL, NULL, 0);\
-	                (_m) = NULL;                                    \
-	                _action;                                        \
-	        } else {                                                \
-	                VERIFY(_n != (_m));                             \
-	                (_m) = _n;                                      \
-	        }                                                       \
-	}                                                               \
-} while (0)
-#endif /* !__i386__ && !__x86_64__ && !__arm64__ */
-
-
-typedef enum ip_check_if_result {
-	IP_CHECK_IF_NONE = 0,
-	IP_CHECK_IF_OURS = 1,
-	IP_CHECK_IF_DROP = 2,
-	IP_CHECK_IF_FORWARD = 3
-} ip_check_if_result_t;
-
-static ip_check_if_result_t ip_input_check_interface(struct mbuf **, struct ip *, struct ifnet *);
-
-/*
- * GRE input handler function, settable via ip_gre_register_input() for PPTP.
- */
-static gre_input_func_t gre_input_func;
-
-static void
-ip_init_delayed(void)
-{
-	struct ifreq ifr;
-	int error;
-	struct sockaddr_in *__single sin;
-
-	bzero(&ifr, sizeof(ifr));
-	strlcpy(ifr.ifr_name, "lo0", sizeof(ifr.ifr_name));
-	sin = SIN(&ifr.ifr_addr);
-	sin->sin_len = sizeof(struct sockaddr_in);
-	sin->sin_family = AF_INET;
-	sin->sin_addr.s_addr = htonl(INADDR_LOOPBACK);
-	error = in_control(NULL, SIOCSIFADDR, (caddr_t)&ifr, lo_ifp, kernproc);
-	if (error) {
-		printf("%s: failed to initialise lo0's address, error=%d\n",
-		    __func__, error);
-	}
-}
+#ifdef __APPLE__
+extern struct mbuf*	m_dup(register struct mbuf *m, int how);
+#endif
+
+static void	save_rte(u_char *, struct in_addr);
+static int	ip_dooptions(struct mbuf *, int, struct sockaddr_in *, struct route *ipforward_rt);
+static void	ip_forward(struct mbuf *, int, struct sockaddr_in *, struct route *ipforward_rt);
+static void	ip_freef(struct ipq *);
+#if IPDIVERT
+#ifdef IPDIVERT_44
+static struct	mbuf *ip_reass(struct mbuf *,
+			struct ipq *, struct ipq *, u_int32_t *, u_int16_t *);
+#else
+static struct	mbuf *ip_reass(struct mbuf *,
+			struct ipq *, struct ipq *, u_int16_t *, u_int16_t *);
+#endif
+#else
+static struct	mbuf *ip_reass(struct mbuf *, struct ipq *, struct ipq *);
+#endif
+void	ipintr(void);
+
+#if RANDOM_IP_ID
+extern u_short ip_id;
+#endif
+
+extern u_long  route_generation;
+extern int apple_hwcksum_rx;
 
 /*
  * IP initialization: fill in IP protocol switch table.
  * All protocols not implemented in kernel go to raw IP protocol handler.
  */
 void
-ip_init(struct protosw *pp, struct domain *dp)
+ip_init()
 {
-	static int ip_initialized = 0;
-	struct protosw *__single pr;
-	struct timeval tv;
-	int i;
-
-	domain_proto_mtx_lock_assert_held();
-	VERIFY((pp->pr_flags & (PR_INITIALIZED | PR_ATTACHED)) == PR_ATTACHED);
-
-	/*
-	 * Some ioctls (e.g. SIOCAIFADDR) use ifaliasreq struct, which is
-	 * interchangeable with in_aliasreq; they must have the same size.
-	 */
-	static_assert(sizeof(struct ifaliasreq) == sizeof(struct in_aliasreq));
-
-	if (!os_atomic_cmpxchg(&ip_initialized, 0, 1, relaxed)) {
-		return;
-	}
-
-	TAILQ_INIT(&in_ifaddrhead);
-	in_ifaddrhashtbl_init();
-
-	ip_moptions_init();
-
-	pr = pffindproto_locked(PF_INET, IPPROTO_RAW, SOCK_RAW);
-	if (pr == NULL) {
-		panic("%s: Unable to find [PF_INET,IPPROTO_RAW,SOCK_RAW]",
-		    __func__);
-		/* NOTREACHED */
-	}
-
-	/* Initialize the entire ip_protox[] array to IPPROTO_RAW. */
-	for (i = 0; i < IPPROTO_MAX; i++) {
-		ip_protox[i] = pr;
-	}
-	/*
-	 * Cycle through IP protocols and put them into the appropriate place
-	 * in ip_protox[], skipping protocols IPPROTO_{IP,RAW}.
-	 */
-	VERIFY(dp == inetdomain && dp->dom_family == PF_INET);
-	TAILQ_FOREACH(pr, &dp->dom_protosw, pr_entry) {
-		VERIFY(pr->pr_domain == dp);
-		if (pr->pr_protocol != 0 && pr->pr_protocol != IPPROTO_RAW) {
-			/* Be careful to only index valid IP protocols. */
-			if (pr->pr_protocol < IPPROTO_MAX) {
+	register struct protosw *pr;
+	register int i;
+	static ip_initialized = 0;
+	struct timeval timenow;
+
+
+	if (!ip_initialized)
+	{
+		TAILQ_INIT(&in_ifaddrhead);
+		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 */
+			if (pr->pr_domain->dom_family == PF_INET &&
+			    pr->pr_protocol && pr->pr_protocol != IPPROTO_RAW)
 				ip_protox[pr->pr_protocol] = pr;
-			}
-		}
-	}
-
-	lck_mtx_lock(&ipqlock);
-	/* Initialize IP reassembly queue. */
-	for (i = 0; i < IPREASS_NHASH; i++) {
-		TAILQ_INIT(&ipq[i]);
-	}
-
-	maxnipq = 8192;
+		}
+		for (i = 0; i < IPREASS_NHASH; i++)
+		    ipq[i].next = ipq[i].prev = &ipq[i];
+
+	maxnipq = nmbclusters / 32;
+	maxfrags = maxnipq * 2;
 	maxfragsperpacket = 128; /* enough for 64k in 512 byte fragments */
-	ipq_updateparams();
-	lck_mtx_unlock(&ipqlock);
-
-	getmicrotime(&tv);
-	ip_id = (u_short)(RandomULong() ^ tv.tv_usec);
-
-	PE_parse_boot_argn("ip_checkinterface", &i, sizeof(i));
-	switch (i) {
-	case IP_CHECKINTERFACE_WEAK_ES:
-	case IP_CHECKINTERFACE_HYBRID_ES:
-	case IP_CHECKINTERFACE_STRONG_ES:
-		ip_checkinterface = i;
-		break;
-	default:
-		break;
-	}
-
-	net_init_add(ip_init_delayed);
+
+#if RANDOM_IP_ID
+		getmicrouptime(&timenow);
+		ip_id = timenow.tv_sec & 0xffff;
+#endif
+		ipintrq.ifq_maxlen = ipqmaxlen;
+
+		ipf_init();
+
+		ip_mutex_grp_attr  = lck_grp_attr_alloc_init();
+		lck_grp_attr_setdefault(ip_mutex_grp_attr);
+
+		ip_mutex_grp = lck_grp_alloc_init("ip", ip_mutex_grp_attr);
+
+		ip_mutex_attr = lck_attr_alloc_init();
+
+		lck_attr_setdefault(ip_mutex_attr);
+
+		if ((ip_mutex = lck_mtx_alloc_init(ip_mutex_grp, ip_mutex_attr)) == NULL) {
+			printf("ip_init: can't alloc ip_mutex\n");
+			return;
+		}
+
+		ip_initialized = 1;
+	}
 }
 
-/*
- * Initialize IPv4 source address hash table.
- */
 static void
-in_ifaddrhashtbl_init(void)
+ip_proto_input(
+	protocol_family_t	protocol,
+	mbuf_t				packet)
 {
-	int i, k, p;
-	uint32_t nhash = 0;
-	uint32_t hash_size;
-
-	if (in_ifaddrhashtbl != NULL) {
-		return;
-	}
-
-	PE_parse_boot_argn("inaddr_nhash", &nhash,
-	    sizeof(inaddr_nhash));
-	if (nhash == 0) {
-		nhash = INADDR_NHASH;
-	}
-
-	hash_size = nhash * sizeof(*in_ifaddrhashtbl);
-
-	in_ifaddrhashtbl = zalloc_permanent(
-		hash_size,
-		ZALIGN_PTR);
-	inaddr_nhash = nhash;
-
-	/*
-	 * 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;
+	ip_input(packet);
 }
 
-uint32_t
-inaddr_hashval(uint32_t key)
+/* 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; 
+
+	if (!inetdomain_initted)
+	{
+		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);
+		lck_mtx_lock(domain_proto_mtx);	
+	}
+}
+
+__private_extern__ void
+ip_proto_dispatch_in(
+					struct mbuf	*m,
+					int			hlen,
+					u_int8_t	proto,
+					ipfilter_t	inject_ipfref)
 {
-	/*
-	 * 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;
-	}
-}
-
-struct in_ifaddrhashhead *
-inaddr_hashlookup(uint32_t key)
-{
-	return &in_ifaddrhashtbl[inaddr_hashval(key)];
-}
-
-static void
-log_wake_ip_mbuf(struct ifnet *ifp, struct mbuf *m)
-{
-	char buffer[64];
-	size_t buflen = MIN(mbuf_pkthdr_len(m), sizeof(buffer));
-
-	os_log(wake_packet_log_handle, "LPW IP packet from %s len %d wakepkt: %d",
-	    ifp->if_xname, m_pktlen(m), (m->m_pkthdr.pkt_flags & PKTF_WAKE_PKT));
-	if (mbuf_copydata(m, 0, buflen, buffer) == 0) {
-		log_hexdump(wake_packet_log_handle, buffer, buflen);
-	}
-}
-
-static void
-ip_proto_process_lpw_packet(struct mbuf *m)
-{
-	struct ifnet *ifp = m->m_pkthdr.rcvif;
-	struct ip *ip = mtod(m, struct ip *);
-
-	/*
-	 * Do nothing for protocol that can handle LPW mode
-	 */
-	switch (ip->ip_p) {
-	case IPPROTO_TCP:
-	case IPPROTO_UDP:
-		return;
-	default:
-		break;
-	}
-
-	if (net_wake_pkt_debug > 0) {
-		log_wake_ip_mbuf(ifp, m);
-	}
-	if_ports_used_match_mbuf(ifp, PF_INET, m);
-	if_exit_lpw(ifp, "IP packet");
-}
-
-__private_extern__ void
-ip_proto_dispatch_in(struct mbuf *m, int hlen, u_int8_t proto,
-    ipfilter_t inject_ipfref)
-{
-	struct ipfilter *__single filter;
-	int seen = (inject_ipfref == NULL);
-	int     changed_header = 0;
+	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)) {
+
+	if (!TAILQ_EMPTY(&ipv4_filters)) {	
 		ipf_ref();
 		TAILQ_FOREACH(filter, &ipv4_filters, ipf_link) {
 			if (seen == 0) {
-				if ((struct ipfilter *)inject_ipfref == filter) {
+				if ((struct ipfilter *)inject_ipfref == filter)
 					seen = 1;
-				}
 			} else if (filter->ipf_filter.ipf_input) {
 				errno_t result;
-
+		
 				if (changed_header == 0) {
-					/*
-					 * Perform IP header alignment fixup,
-					 * if needed, before passing packet
-					 * into filter(s).
-					 */
-					IP_HDR_ALIGNMENT_FIXUP(m,
-					    m->m_pkthdr.rcvif, ipf_unref());
-
-					/* ipf_unref() already called */
-					if (m == NULL) {
-						return;
-					}
-
 					changed_header = 1;
 					ip = mtod(m, struct ip *);
-					ip->ip_len = htons(ip->ip_len + (uint16_t)hlen);
+					ip->ip_len = htons(ip->ip_len + hlen);
 					ip->ip_off = htons(ip->ip_off);
 					ip->ip_sum = 0;
-					ip->ip_sum = ip_cksum_hdr_in(m, hlen);
+					ip->ip_sum = in_cksum(m, hlen);
 				}
 				result = filter->ipf_filter.ipf_input(
-					filter->ipf_filter.cookie, (mbuf_t *)&m,
-					hlen, proto);
+					filter->ipf_filter.cookie, (mbuf_t*)&m, hlen, proto);
 				if (result == EJUSTRETURN) {
 					ipf_unref();
 					return;
 				}
 				if (result != 0) {
-					ipstat.ips_input_ipf_drop++;
 					ipf_unref();
-					m_drop(m, DROPTAP_FLAG_DIR_IN | DROPTAP_FLAG_L2_MISSING, DROP_REASON_IP_FILTER_DROP,
-					    NULL, 0);
+					m_freem(m);
 					return;
 				}
-			}
+	}
 		}
 		ipf_unref();
 	}
-
-	/* Perform IP header alignment fixup (post-filters), if needed */
-	IP_HDR_ALIGNMENT_FIXUP(m, m->m_pkthdr.rcvif, return );
-
-	ip = mtod(m, struct ip *);
-
-	if (changed_header) {
-		ip->ip_len = ntohs(ip->ip_len) - (u_short)hlen;
-		ip->ip_off = ntohs(ip->ip_off);
-	}
-
-	/*
-	 * Check if need to switch to full wake mode -- only TCP knows about idle connections
-	 */
-	if (__improbable(if_is_lpw_enabled(m->m_pkthdr.rcvif))) {
-		ip_proto_process_lpw_packet(m);
-	}
-
 	/*
 	 * 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
 	 */
-	if ((pr_input = ip_protox[ip->ip_p]->pr_input) == NULL) {
-		ipstat.ips_input_no_proto++;
-		m_drop(m, DROPTAP_FLAG_DIR_IN | DROPTAP_FLAG_L2_MISSING, DROP_REASON_IP_NO_PROTO,
-		    NULL, 0);
-	} else if (!(ip_protox[ip->ip_p]->pr_flags & PR_PROTOLOCK)) {
+	ip = mtod(m, struct ip *);
+	
+	if (changed_header) {
+		ip->ip_len = ntohs(ip->ip_len) - hlen;
+		ip->ip_off = ntohs(ip->ip_off);
+	}
+	
+	if (!(ip_protox[ip->ip_p]->pr_flags & PR_PROTOLOCK)) {
 		lck_mtx_lock(inet_domain_mutex);
-		pr_input(m, hlen);
+		(*ip_protox[ip->ip_p]->pr_input)(m, hlen);
 		lck_mtx_unlock(inet_domain_mutex);
-	} else {
-		pr_input(m, hlen);
-	}
+	}	
+	else	 
+		(*ip_protox[ip->ip_p]->pr_input)(m, hlen);
+		
 }
 
-struct pktchain_elm {
-	struct mbuf     *pkte_head;
-	struct mbuf     *pkte_tail;
-	struct in_addr  pkte_saddr;
-	struct in_addr  pkte_daddr;
-	uint16_t        pkte_npkts;
-	uint16_t        pkte_proto;
-	uint32_t        pkte_nbytes;
-};
-
-typedef struct pktchain_elm pktchain_elm_t;
-
-/* Store upto PKTTBL_SZ unique flows on the stack */
-#define PKTTBL_SZ       7
-
-static struct mbuf *
-ip_chain_insert(struct mbuf *packet, pktchain_elm_t *__counted_by(PKTTBL_SZ) tbl)
+/* 
+ * ipforward_rt cleared in in_addroute()
+ * when a new route is successfully created.
+ */
+static struct	sockaddr_in ipaddr = { sizeof(ipaddr), AF_INET };
+
+/*
+ * Ip input routine.  Checksum and byte swap header.  If fragmented
+ * try to reassemble.  Process options.  Pass to next level.
+ */
+void
+ip_input(struct mbuf *m)
 {
-	struct ip*      ip;
-	int             pkttbl_idx = 0;
-	struct mbuf *head;
-
-	ip = mtod(packet, struct ip*);
-
-	/* reusing the hash function from inaddr_hashval */
-	pkttbl_idx = inaddr_hashval(ntohl(ip->ip_src.s_addr)) % PKTTBL_SZ;
-	head = tbl[pkttbl_idx].pkte_head;
-	if (head == NULL) {
-		tbl[pkttbl_idx].pkte_head = packet;
-		tbl[pkttbl_idx].pkte_saddr.s_addr = ip->ip_src.s_addr;
-		tbl[pkttbl_idx].pkte_daddr.s_addr = ip->ip_dst.s_addr;
-		tbl[pkttbl_idx].pkte_proto = ip->ip_p;
-	} else {
-		if ((ip->ip_dst.s_addr == tbl[pkttbl_idx].pkte_daddr.s_addr) &&
-		    (ip->ip_src.s_addr == tbl[pkttbl_idx].pkte_saddr.s_addr) &&
-		    (ip->ip_p == tbl[pkttbl_idx].pkte_proto) &&
-		    (packet->m_flags & (M_BCAST | M_MCAST)) == (head->m_flags & (M_BCAST | M_MCAST))) {
-		} else {
-			return packet;
-		}
-	}
-	if (tbl[pkttbl_idx].pkte_tail != NULL) {
-		mbuf_setnextpkt(tbl[pkttbl_idx].pkte_tail, packet);
-	}
-
-	tbl[pkttbl_idx].pkte_tail = packet;
-	tbl[pkttbl_idx].pkte_npkts += 1;
-	tbl[pkttbl_idx].pkte_nbytes += packet->m_pkthdr.len;
-	return NULL;
-}
-
-/* args is a dummy variable here for backward compatibility */
-static void
-ip_input_second_pass_loop_tbl(pktchain_elm_t *__counted_by(PKTTBL_SZ) tbl, struct ip_fw_in_args *args)
-{
-	int i = 0;
-
-	for (i = 0; i < PKTTBL_SZ; i++) {
-		if (tbl[i].pkte_head != NULL) {
-			struct mbuf *m = tbl[i].pkte_head;
-			ip_input_second_pass(m, m->m_pkthdr.rcvif,
-			    tbl[i].pkte_npkts, tbl[i].pkte_nbytes, args);
-
-			if (tbl[i].pkte_npkts > 2) {
-				ipstat.ips_rxc_chainsz_gt2++;
-			}
-			if (tbl[i].pkte_npkts > 4) {
-				ipstat.ips_rxc_chainsz_gt4++;
-			}
-#if (DEBUG || DEVELOPMENT)
-			if (ip_input_measure) {
-				net_perf_histogram(&net_perf, tbl[i].pkte_npkts);
-			}
-#endif /* (DEBUG || DEVELOPMENT) */
-			tbl[i].pkte_head = tbl[i].pkte_tail = NULL;
-			tbl[i].pkte_npkts = 0;
-			tbl[i].pkte_nbytes = 0;
-			/* no need to initialize address and protocol in tbl */
-		}
-	}
-}
-
-static void
-ip_input_cpout_args(struct ip_fw_in_args *args, struct ip_fw_args *args1,
-    boolean_t *done_init)
-{
-	if (*done_init == FALSE) {
-		bzero(args1, sizeof(struct ip_fw_args));
-		*done_init = TRUE;
-	}
-	args1->fwa_pf_rule = args->fwai_pf_rule;
-}
-
-static void
-ip_input_cpin_args(struct ip_fw_args *args1, struct ip_fw_in_args *args)
-{
-	args->fwai_pf_rule = args1->fwa_pf_rule;
-}
-
-typedef enum {
-	IPINPUT_DOCHAIN = 0,
-	IPINPUT_DONTCHAIN,
-	IPINPUT_FREED,
-	IPINPUT_DONE
-} ipinput_chain_ret_t;
-
-static void
-ip_input_update_nstat(struct ifnet *ifp, struct in_addr src_ip,
-    u_int32_t packets, u_int32_t bytes)
-{
-	if (nstat_collect) {
-		struct rtentry *rt = ifnet_cached_rtlookup_inet(ifp,
-		    src_ip);
-		if (rt != NULL) {
-			nstat_route_rx(rt, packets, bytes, 0);
-			rtfree(rt);
-		}
-	}
-}
-
-static void
-ip_input_dispatch_chain(struct mbuf *m)
-{
-	mbuf_ref_t tmp_mbuf = m;
-	mbuf_ref_t nxt_mbuf = NULL;
-	struct ip *__single ip = NULL;
-	unsigned int hlen;
-
-	ip = mtod(tmp_mbuf, struct ip *);
-	hlen = IP_VHL_HL(ip->ip_vhl) << 2;
-	while (tmp_mbuf != NULL) {
-		nxt_mbuf = mbuf_nextpkt(tmp_mbuf);
-		mbuf_setnextpkt(tmp_mbuf, NULL);
-		ip_proto_dispatch_in(tmp_mbuf, hlen, ip->ip_p, 0);
-		tmp_mbuf = nxt_mbuf;
-		if (tmp_mbuf) {
-			ip = mtod(tmp_mbuf, struct ip *);
-			/* first mbuf of chain already has adjusted ip_len */
-			hlen = IP_VHL_HL(ip->ip_vhl) << 2;
-			ip->ip_len -= hlen;
-		}
-	}
-}
-
-static void
-ip_input_setdst_chain(struct mbuf *m, uint16_t ifindex, struct in_ifaddr *ia)
-{
-	mbuf_ref_t tmp_mbuf = m;
-
-	while (tmp_mbuf != NULL) {
-		ip_setdstifaddr_info(tmp_mbuf, ifindex, ia);
-		tmp_mbuf = mbuf_nextpkt(tmp_mbuf);
-	}
-}
-
-static void
-ip_input_adjust(struct mbuf *m, struct ip *ip, struct ifnet *inifp)
-{
-	boolean_t adjust = TRUE;
-
-	ASSERT(m_pktlen(m) > ip->ip_len);
-
-	/*
-	 * Invalidate hardware checksum info if ip_adj_clear_hwcksum
-	 * is set; useful to handle buggy drivers.  Note that this
-	 * should not be enabled by default, as we may get here due
-	 * to link-layer padding.
-	 */
-	if (ip_adj_clear_hwcksum &&
-	    (m->m_pkthdr.csum_flags & CSUM_DATA_VALID) &&
-	    !(inifp->if_flags & IFF_LOOPBACK) &&
-	    !(m->m_pkthdr.pkt_flags & PKTF_LOOP)) {
-		m->m_pkthdr.csum_flags &= ~CSUM_DATA_VALID;
-		m->m_pkthdr.csum_data = 0;
-		ipstat.ips_adj_hwcsum_clr++;
-	}
-
-	/*
-	 * If partial checksum information is available, subtract
-	 * out the partial sum of postpended extraneous bytes, and
-	 * update the checksum metadata accordingly.  By doing it
-	 * here, the upper layer transport only needs to adjust any
-	 * prepended extraneous bytes (else it will do both.)
-	 */
-	if (ip_adj_partial_sum &&
-	    (m->m_pkthdr.csum_flags & (CSUM_DATA_VALID | CSUM_PARTIAL)) ==
-	    (CSUM_DATA_VALID | CSUM_PARTIAL)) {
-		m->m_pkthdr.csum_rx_val = m_adj_sum16(m,
-		    m->m_pkthdr.csum_rx_start, m->m_pkthdr.csum_rx_start,
-		    (ip->ip_len - m->m_pkthdr.csum_rx_start),
-		    m->m_pkthdr.csum_rx_val);
-	} else if ((m->m_pkthdr.csum_flags &
-	    (CSUM_DATA_VALID | CSUM_PARTIAL)) ==
-	    (CSUM_DATA_VALID | CSUM_PARTIAL)) {
-		/*
-		 * If packet has partial checksum info and we decided not
-		 * to subtract the partial sum of postpended extraneous
-		 * bytes here (not the default case), leave that work to
-		 * be handled by the other layers.  For now, only TCP, UDP
-		 * layers are capable of dealing with this.  For all other
-		 * protocols (including fragments), trim and ditch the
-		 * partial sum as those layers might not implement partial
-		 * checksumming (or adjustment) at all.
-		 */
-		if ((ip->ip_off & (IP_MF | IP_OFFMASK)) == 0 &&
-		    (ip->ip_p == IPPROTO_TCP || ip->ip_p == IPPROTO_UDP)) {
-			adjust = FALSE;
-		} else {
-			m->m_pkthdr.csum_flags &= ~CSUM_DATA_VALID;
-			m->m_pkthdr.csum_data = 0;
-			ipstat.ips_adj_hwcsum_clr++;
-		}
-	}
-
-	if (adjust) {
-		ipstat.ips_adj++;
-		if (m->m_len == m->m_pkthdr.len) {
-			m->m_len = ip->ip_len;
-			m->m_pkthdr.len = ip->ip_len;
-		} else {
-			m_adj(m, ip->ip_len - m->m_pkthdr.len);
-		}
-	}
-}
-
-/*
- * First pass does all essential packet validation and places on a per flow
- * queue for doing operations that have same outcome for all packets of a flow.
- */
-static ipinput_chain_ret_t
-ip_input_first_pass(struct mbuf *m, struct ip_fw_in_args *args, struct mbuf **modm)
-{
-	struct ip       *__single ip;
-	ifnet_ref_t     inifp;
-	unsigned int    hlen;
-	int             retval = IPINPUT_DOCHAIN;
-	int             len = 0;
-	struct in_addr  src_ip;
+	struct ip *ip;
+	struct ipq *fp;
+	struct in_ifaddr *ia = NULL;
+	int    i, hlen, mff, checkif;
+	u_short sum;
+	struct in_addr pkt_dst;
+	u_int32_t div_info = 0;		/* packet divert/tee info */
+	struct ip_fw_args args;
+	ipfilter_t inject_filter_ref = 0;
+	struct m_tag	*tag;
+	struct route	ipforward_rt = { 0 };
+	
+	lck_mtx_lock(ip_mutex);
+
+	args.eh = NULL;
+	args.oif = NULL;
+	args.rule = NULL;
+	args.divert_rule = 0;			/* divert cookie */
+	args.next_hop = NULL;
+
+	/* Grab info from mtags prepended to the chain */
 #if DUMMYNET
-	struct m_tag            *copy;
-	struct m_tag            *p;
-	boolean_t               delete = FALSE;
-	struct ip_fw_args       args1;
-	boolean_t               init = FALSE;
+	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 */
-	ipfilter_t __single inject_filter_ref = NULL;
-
-	/* Check if the mbuf is still valid after interface filter processing */
-	MBUF_INPUT_CHECK(m, m->m_pkthdr.rcvif);
-	inifp = mbuf_pkthdr_rcvif(m);
-	VERIFY(inifp != NULL);
-
-	/* Perform IP header alignment fixup, if needed */
-	IP_HDR_ALIGNMENT_FIXUP(m, inifp, return );
-
-	m->m_pkthdr.pkt_flags &= ~PKTF_FORWARDED;
-
-#if DUMMYNET
-	/*
-	 * 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 */
-	p = m_tag_first(m);
-	while (p) {
-		if (p->m_tag_id == KERNEL_MODULE_TAG_ID) {
-			if (p->m_tag_type == KERNEL_TAG_TYPE_DUMMYNET) {
-				struct dn_pkt_tag *dn_tag;
-
-				dn_tag = (struct dn_pkt_tag *)(p->m_tag_data);
-				args->fwai_pf_rule = dn_tag->dn_pf_rule;
-				delete = TRUE;
-			}
-
-			if (delete) {
-				copy = p;
-				p = m_tag_next(m, p);
-				m_tag_delete(m, copy);
-			} else {
-				p = m_tag_next(m, p);
-			}
-		} else {
-			p = m_tag_next(m, p);
-		}
-	}
-
-#if DIAGNOSTIC
-	if (m == NULL || !(m->m_flags & M_PKTHDR)) {
+
+	if ((tag = m_tag_locate(m, KERNEL_MODULE_TAG_ID, KERNEL_TAG_TYPE_DIVERT, NULL)) != NULL) {
+		struct divert_tag	*div_tag;
+		
+		div_tag = (struct divert_tag *)(tag+1);
+		args.divert_rule = div_tag->cookie;
+
+		m_tag_delete(m, tag);
+	}
+	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
-
-	if (args->fwai_pf_rule) {
-		/* dummynet already filtered us */
+#endif
+
+	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 ;
+	}
+	
+	/*
+	 * No need to proccess packet twice if we've 
+	 * already seen it
+	 */
+	inject_filter_ref = ipf_get_inject_filter(m);
+	if (inject_filter_ref != 0) {
+		lck_mtx_unlock(ip_mutex);
 		ip = mtod(m, struct ip *);
 		hlen = IP_VHL_HL(ip->ip_vhl) << 2;
-		inject_filter_ref = ipf_get_inject_filter(m);
-		if (args->fwai_pf_rule) {
-			goto check_with_pf;
-		}
-	}
-ipfw_tags_done:
-#endif /* DUMMYNET */
-
-	/*
-	 * No need to process 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 != NULL) {
-		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 *, inifp,
-		    struct ip *, ip, struct ip6_hdr *, NULL);
-
-		ip->ip_len = ntohs(ip->ip_len) - (u_short)hlen;
+		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 IPINPUT_DONE;
-	}
-
-	if (__improbable(m->m_pkthdr.pkt_flags & PKTF_WAKE_PKT)) {
-		if_ports_used_match_mbuf(inifp, PF_INET, m);
-	}
-
-	if (m->m_pkthdr.len < sizeof(struct ip)) {
-		OSAddAtomic(1, &ipstat.ips_total);
-		OSAddAtomic(1, &ipstat.ips_tooshort);
-		m_drop(m, DROPTAP_FLAG_DIR_IN | DROPTAP_FLAG_L2_MISSING, DROP_REASON_IP_TOO_SHORT,
-		    NULL, 0);
-		return IPINPUT_FREED;
-	}
-
-	if (m->m_len < sizeof(struct ip) &&
-	    (m = m_pullup(m, sizeof(struct ip))) == NULL) {
-		OSAddAtomic(1, &ipstat.ips_total);
-		OSAddAtomic(1, &ipstat.ips_toosmall);
-		return IPINPUT_FREED;
-	}
-
+		return;
+	}
+
+	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++;
+		lck_mtx_unlock(ip_mutex);
+		return;
+	}
 	ip = mtod(m, struct ip *);
-	*modm = m;
-
-	KERNEL_DEBUG(DBG_LAYER_BEG, ip->ip_dst.s_addr, ip->ip_src.s_addr,
-	    ip->ip_p, ip->ip_off, ip->ip_len);
+
+	KERNEL_DEBUG(DBG_LAYER_BEG, ip->ip_dst.s_addr, 
+		     ip->ip_src.s_addr, ip->ip_p, ip->ip_off, ip->ip_len);
 
 	if (IP_VHL_V(ip->ip_vhl) != IPVERSION) {
-		OSAddAtomic(1, &ipstat.ips_total);
-		OSAddAtomic(1, &ipstat.ips_badvers);
-		KERNEL_DEBUG(DBG_LAYER_END, 0, 0, 0, 0, 0);
-		m_drop(m, DROPTAP_FLAG_DIR_IN | DROPTAP_FLAG_L2_MISSING, DROP_REASON_IP_BAD_VERSION,
-		    NULL, 0);
-		return IPINPUT_FREED;
+		ipstat.ips_badvers++;
+		goto bad;
 	}
 
 	hlen = IP_VHL_HL(ip->ip_vhl) << 2;
-	if (hlen < sizeof(struct ip)) {
-		OSAddAtomic(1, &ipstat.ips_total);
-		OSAddAtomic(1, &ipstat.ips_badhlen);
-		KERNEL_DEBUG(DBG_LAYER_END, 0, 0, 0, 0, 0);
-		m_drop(m, DROPTAP_FLAG_DIR_IN | DROPTAP_FLAG_L2_MISSING, DROP_REASON_IP_BAD_HDR_LENGTH,
-		    NULL, 0);
-		return IPINPUT_FREED;
-	}
-
+	if (hlen < sizeof(struct ip)) {	/* minimum header length */
+		ipstat.ips_badhlen++;
+		goto bad;
+	}
 	if (hlen > m->m_len) {
-		if ((m = m_pullup(m, hlen)) == NULL) {
-			OSAddAtomic(1, &ipstat.ips_total);
-			OSAddAtomic(1, &ipstat.ips_badhlen);
-			KERNEL_DEBUG(DBG_LAYER_END, 0, 0, 0, 0, 0);
-			return IPINPUT_FREED;
+		if ((m = m_pullup(m, hlen)) == 0) {
+			ipstat.ips_badhlen++;
+			lck_mtx_unlock(ip_mutex);
+			return;
 		}
 		ip = mtod(m, struct ip *);
-		*modm = m;
-	}
-
-	if ((ip->ip_tos & IPTOS_ECN_MASK) == IPTOS_ECN_ECT1) {
-		m->m_pkthdr.pkt_ext_flags |= PKTF_EXT_L4S;
 	}
 
 	/* 127/8 must not appear on wire - RFC1122 */
 	if ((ntohl(ip->ip_dst.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET ||
 	    (ntohl(ip->ip_src.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET) {
-		/*
-		 * Allow for the following exceptions:
-		 *
-		 *   1. If the packet was sent to loopback (i.e. rcvif
-		 *      would have been set earlier at output time.)
-		 *
-		 *   2. If the packet was sent out on loopback from a local
-		 *      source address which belongs to a non-loopback
-		 *      interface (i.e. rcvif may not necessarily be a
-		 *      loopback interface, hence the test for PKTF_LOOP.)
-		 *      Unlike IPv6, there is no interface scope ID, and
-		 *      therefore we don't care so much about PKTF_IFINFO.
-		 */
-		if (!(inifp->if_flags & IFF_LOOPBACK) &&
-		    !(m->m_pkthdr.pkt_flags & PKTF_LOOP)) {
-			OSAddAtomic(1, &ipstat.ips_total);
-			OSAddAtomic(1, &ipstat.ips_badaddr);
-			KERNEL_DEBUG(DBG_LAYER_END, 0, 0, 0, 0, 0);
-			m_drop(m, DROPTAP_FLAG_DIR_IN | DROPTAP_FLAG_L2_MISSING, DROP_REASON_IP_INVALID_ADDR,
-			    NULL, 0);
-			return IPINPUT_FREED;
-		}
-	}
-
-	/* IPv4 Link-Local Addresses as defined in RFC3927 */
-	if ((IN_LINKLOCAL(ntohl(ip->ip_dst.s_addr)) ||
+		if ((m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) == 0) {
+			ipstat.ips_badaddr++;
+			goto bad;
+		}
+	}
+
+	/* IPv4 Link-Local Addresses as defined in <draft-ietf-zeroconf-ipv4-linklocal-05.txt> */
+	if ((IN_LINKLOCAL(ntohl(ip->ip_dst.s_addr)) || 
 	    IN_LINKLOCAL(ntohl(ip->ip_src.s_addr)))) {
 		ip_linklocal_stat.iplls_in_total++;
 		if (ip->ip_ttl != MAXTTL) {
-			OSAddAtomic(1, &ip_linklocal_stat.iplls_in_badttl);
+			ip_linklocal_stat.iplls_in_badttl++;
 			/* Silently drop link local traffic with bad TTL */
-			if (!ip_linklocal_in_allowbadttl) {
-				OSAddAtomic(1, &ipstat.ips_total);
-				KERNEL_DEBUG(DBG_LAYER_END, 0, 0, 0, 0, 0);
-				m_drop(m, DROPTAP_FLAG_DIR_IN | DROPTAP_FLAG_L2_MISSING, DROP_REASON_IP_BAD_TTL,
-				    NULL, 0);
-				return IPINPUT_FREED;
-			}
-		}
-	}
-
-	if (ip_cksum(m, hlen)) {
-		OSAddAtomic(1, &ipstat.ips_total);
-		KERNEL_DEBUG(DBG_LAYER_END, 0, 0, 0, 0, 0);
-		m_drop(m, DROPTAP_FLAG_DIR_IN | DROPTAP_FLAG_L2_MISSING, DROP_REASON_IP_BAD_CHECKSUM,
-		    NULL, 0);
-		return IPINPUT_FREED;
-	}
-
-	DTRACE_IP6(receive, struct mbuf *, m, struct inpcb *, NULL,
-	    struct ip *, ip, struct ifnet *, inifp,
-	    struct ip *, ip, struct ip6_hdr *, NULL);
+			if (!ip_linklocal_in_allowbadttl)
+				goto bad;
+		}
+	}
+	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 {
+		sum = in_cksum(m, hlen);
+	}
+	if (sum) {
+		ipstat.ips_badsum++;
+		goto bad;
+	}
 
 	/*
 	 * Convert fields to host representation.
 	 */
-#if BYTE_ORDER != BIG_ENDIAN
 	NTOHS(ip->ip_len);
-#endif
-
 	if (ip->ip_len < hlen) {
-		OSAddAtomic(1, &ipstat.ips_total);
-		OSAddAtomic(1, &ipstat.ips_badlen);
-		KERNEL_DEBUG(DBG_LAYER_END, 0, 0, 0, 0, 0);
-		m_drop(m, DROPTAP_FLAG_DIR_IN | DROPTAP_FLAG_L2_MISSING, DROP_REASON_IP_BAD_LENGTH,
-		    NULL, 0);
-		return IPINPUT_FREED;
-	}
-
-#if BYTE_ORDER != BIG_ENDIAN
+		ipstat.ips_badlen++;
+		goto bad;
+	}
 	NTOHS(ip->ip_off);
-#endif
 
 	/*
 	 * Check that the amount of data in the buffers
@@ -1216,321 +642,124 @@
 	 * Drop packet if shorter than we expect.
 	 */
 	if (m->m_pkthdr.len < ip->ip_len) {
-		OSAddAtomic(1, &ipstat.ips_total);
-		OSAddAtomic(1, &ipstat.ips_tooshort);
-		KERNEL_DEBUG(DBG_LAYER_END, 0, 0, 0, 0, 0);
-		m_drop(m, DROPTAP_FLAG_DIR_IN | DROPTAP_FLAG_L2_MISSING, DROP_REASON_IP_TOO_SHORT,
-		    NULL, 0);
-		return IPINPUT_FREED;
-	}
-
+tooshort:
+		ipstat.ips_tooshort++;
+		goto bad;
+	}
 	if (m->m_pkthdr.len > ip->ip_len) {
-		ip_input_adjust(m, ip, inifp);
-	}
-
-	/* for netstat route statistics */
-	src_ip = ip->ip_src;
-	len = m->m_pkthdr.len;
-
+		/* Invalidate hwcksuming */
+		m->m_pkthdr.csum_flags = 0;
+		m->m_pkthdr.csum_data = 0;
+
+		if (m->m_len == m->m_pkthdr.len) {
+			m->m_len = ip->ip_len;
+			m->m_pkthdr.len = ip->ip_len;
+		} else
+			m_adj(m, ip->ip_len - m->m_pkthdr.len);
+	}
+
+#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)
+iphack:
+#endif
+	/*
+	 * Check if we want to allow this packet to be processed.
+	 * Consider it to be bad if not.
+	 */
+	if (fr_checkp) {
+		struct	mbuf	*m1 = m;
+
+		if (fr_checkp(ip, hlen, m->m_pkthdr.rcvif, 0, &m1) || !m1)
+			return;
+		ip = mtod(m = m1, struct ip *);
+	}
+	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 (args.next_hop)
+			goto ours;
+#endif	/* IPFIREWALL_FORWARD */
+
+		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);
+			lck_mtx_unlock(ip_mutex);
+			return;
+		}
+		ip = mtod(m, struct ip *); /* just in case m changed */
+		if (i == 0 && args.next_hop == NULL)	/* common case */
+			goto pass;
 #if DUMMYNET
-check_with_pf:
+                if (DUMMYNET_LOADED && (i & IP_FW_PORT_DYNT_FLAG) != 0) {
+			/* Send packet to the appropriate pipe */
+			lck_mtx_unlock(ip_mutex);
+			ip_dn_io_ptr(m, i&0xffff, DN_TO_IP_IN, &args);
+			return;
+		}
 #endif /* DUMMYNET */
-#if PF
-	/* Invoke inbound packet filter */
-	if (PF_IS_ENABLED) {
-		int error;
-		ip_input_cpout_args(args, &args1, &init);
-		ip = mtod(m, struct ip *);
-		src_ip = ip->ip_src;
-
-#if DUMMYNET
-		error = pf_af_hook(inifp, NULL, &m, AF_INET, TRUE, &args1);
-#else
-		error = pf_af_hook(inifp, NULL, &m, AF_INET, TRUE, NULL);
-#endif /* DUMMYNET */
-		if (error != 0 || m == NULL) {
-			if (m != NULL) {
-				panic("%s: unexpected packet %p",
-				    __func__, m);
-				/* NOTREACHED */
-			}
-			/* Already freed by callee */
-			ip_input_update_nstat(inifp, src_ip, 1, len);
-			KERNEL_DEBUG(DBG_LAYER_END, 0, 0, 0, 0, 0);
-			OSAddAtomic(1, &ipstat.ips_total);
-			return IPINPUT_FREED;
-		}
-		ip = mtod(m, struct ip *);
-		hlen = IP_VHL_HL(ip->ip_vhl) << 2;
-		*modm = m;
-		ip_input_cpin_args(&args1, args);
-	}
-#endif /* PF */
-
-#if IPSEC
-	if (ipsec_bypass == 0 && ipsec_get_history_count(m)) {
-		retval = IPINPUT_DONTCHAIN; /* XXX scope for chaining here? */
-		goto pass;
-	}
-#endif
-
-#if IPSEC
+#if IPDIVERT
+		if (i != 0 && (i & IP_FW_PORT_DYNT_FLAG) == 0) {
+			/* Divert or tee packet */
+			div_info = i;
+			goto ours;
+		}
+#endif
+#if IPFIREWALL_FORWARD
+		if (i == 0 && args.next_hop != NULL)
+			goto pass;
+#endif
+		/*
+		 * if we get here, the packet must be dropped
+		 */
+		m_freem(m);
+		lck_mtx_unlock(ip_mutex);
+		return;
+	}
 pass:
-#endif
+
 	/*
 	 * Process options and, if not destined for us,
 	 * ship it on.  ip_dooptions returns 1 when an
 	 * error was detected (causing an icmp message
 	 * 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, 0, NULL)) {
-		src_ip = ip->ip_src;
-		ip_input_update_nstat(inifp, src_ip, 1, len);
-		KERNEL_DEBUG(DBG_LAYER_END, 0, 0, 0, 0, 0);
-		OSAddAtomic(1, &ipstat.ips_total);
-		return IPINPUT_FREED;
-	}
-
-	/*
-	 * Don't chain fragmented packets
-	 */
-	if (ip->ip_off & ~(IP_DF | IP_RF)) {
-		return IPINPUT_DONTCHAIN;
-	}
-
-	/* Allow DHCP/BootP responses through */
-	if ((inifp->if_eflags & IFEF_AUTOCONFIGURING) &&
-	    hlen == sizeof(struct ip) && ip->ip_p == IPPROTO_UDP) {
-		struct udpiphdr *__single ui;
-
-		if (m->m_len < sizeof(struct udpiphdr) &&
-		    (m = m_pullup(m, sizeof(struct udpiphdr))) == NULL) {
-			OSAddAtomic(1, &udpstat.udps_hdrops);
-			KERNEL_DEBUG(DBG_LAYER_END, 0, 0, 0, 0, 0);
-			OSAddAtomic(1, &ipstat.ips_total);
-			return IPINPUT_FREED;
-		}
-		*modm = m;
-		ui = mtod(m, struct udpiphdr *);
-		if (ntohs(ui->ui_dport) == IPPORT_BOOTPC) {
-			ip_setdstifaddr_info(m, inifp->if_index, NULL);
-			return IPINPUT_DONTCHAIN;
-		}
-	}
-
-	/* Avoid chaining raw sockets as ipsec checks occur later for them */
-	if (ip_protox[ip->ip_p]->pr_flags & PR_LASTHDR) {
-		return IPINPUT_DONTCHAIN;
-	}
-
-	return retval;
-}
-
-/*
- * Because the call to m_pullup() may freem the mbuf, the function frees the mbuf packet
- * chain before it return IP_CHECK_IF_DROP
- */
-static ip_check_if_result_t
-ip_input_check_interface(struct mbuf **mp, struct ip *ip, struct ifnet *inifp)
-{
-	mbuf_ref_t m = *mp;
-	struct in_ifaddr *__single ia = NULL;
-	struct in_ifaddr *__single best_ia = NULL;
-	ifnet_ref_t match_ifp = NULL;
-	ip_check_if_result_t result = IP_CHECK_IF_NONE;
-	enum drop_reason drop_reason = DROP_REASON_IP_RCV_IF_NO_MATCH;
-
-	/*
-	 * Host broadcast and all network broadcast addresses are always a match
-	 */
-	if (ip->ip_dst.s_addr == (u_int32_t)INADDR_BROADCAST ||
-	    ip->ip_dst.s_addr == INADDR_ANY) {
-		ip_input_setdst_chain(m, inifp->if_index, NULL);
-		return IP_CHECK_IF_OURS;
-	}
-
-	/*
-	 * Check for a match in the hash bucket.
-	 */
-	lck_rw_lock_shared(&in_ifaddr_rwlock);
-	TAILQ_FOREACH(ia, INADDR_HASH(ip->ip_dst.s_addr), ia_hash) {
-		if (IA_SIN(ia)->sin_addr.s_addr == ip->ip_dst.s_addr) {
-			best_ia = ia;
-			match_ifp = best_ia->ia_ifp;
-
-			if (ia->ia_ifp == inifp || (inifp->if_flags & IFF_LOOPBACK) ||
-			    (m->m_pkthdr.pkt_flags & PKTF_LOOP)) {
-				/*
-				 * A locally originated packet or packet from the loopback
-				 * interface is always an exact interface address match
-				 */
-				match_ifp = inifp;
-				break;
-			}
-			/*
-			 * Continue the loop in case there's a exact match with another
-			 * interface
-			 */
-		}
-	}
-	if (best_ia != NULL) {
-		if (match_ifp != inifp && ipforwarding == 0 &&
-		    ((ip_checkinterface == IP_CHECKINTERFACE_HYBRID_ES &&
-		    (match_ifp->if_family == IFNET_FAMILY_IPSEC ||
-		    match_ifp->if_family == IFNET_FAMILY_UTUN)) ||
-		    ip_checkinterface == IP_CHECKINTERFACE_STRONG_ES)) {
-			/*
-			 * Drop when interface address check is strict and forwarding
-			 * is disabled
-			 */
-			result = IP_CHECK_IF_DROP;
-		} else {
-			if ((m->m_flags & (M_BCAST | M_MCAST)) != 0) {
-				drop_reason = DROP_REASON_FSW_DEMUX_L2_MULTI_L3_UNI;
-				result = IP_CHECK_IF_DROP;
-			} else {
-				result = IP_CHECK_IF_OURS;
-			}
-			ip_input_setdst_chain(m, 0, best_ia);
-		}
-	}
-	lck_rw_done(&in_ifaddr_rwlock);
-
-	if (result == IP_CHECK_IF_NONE && (inifp->if_flags & IFF_BROADCAST)) {
-		/*
-		 * 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().
-		 */
-		struct ifaddr *__single ifa;
-
-		ifnet_lock_shared(inifp);
-		TAILQ_FOREACH(ifa, &inifp->if_addrhead, ifa_link) {
-			if (ifa->ifa_addr->sa_family != AF_INET) {
-				continue;
-			}
-			ia = ifatoia(ifa);
-			if (satosin(&ia->ia_broadaddr)->sin_addr.s_addr == ip->ip_dst.s_addr ||
-			    ia->ia_netbroadcast.s_addr == ip->ip_dst.s_addr) {
-				ip_input_setdst_chain(m, 0, ia);
-				result = IP_CHECK_IF_OURS;
-				match_ifp = inifp;
-				break;
-			}
-		}
-		ifnet_lock_done(inifp);
-	}
-
-	/* Allow DHCP/BootP responses through */
-	if (result == IP_CHECK_IF_NONE && (inifp->if_eflags & IFEF_AUTOCONFIGURING) &&
-	    ip->ip_p == IPPROTO_UDP && (IP_VHL_HL(ip->ip_vhl) << 2) == sizeof(struct ip)) {
-		struct udpiphdr *__single ui;
-
-		if (m->m_len < sizeof(struct udpiphdr)) {
-			if ((m = m_pullup(m, sizeof(struct udpiphdr))) == NULL) {
-				OSAddAtomic(1, &udpstat.udps_hdrops);
-				*mp = NULL;
-				return IP_CHECK_IF_DROP;
-			}
-			/*
-			 * m_pullup can return a different mbuf
-			 */
-			*mp = m;
-			ip = mtod(m, struct ip *);
-		}
-		ui = mtod(m, struct udpiphdr *);
-		if (ntohs(ui->ui_dport) == IPPORT_BOOTPC) {
-			ip_input_setdst_chain(m, inifp->if_index, NULL);
-			result = IP_CHECK_IF_OURS;
-			match_ifp = inifp;
-		}
-	}
-
-	if (result == IP_CHECK_IF_NONE) {
-		if (ipforwarding == 0) {
-			result = IP_CHECK_IF_DROP;
-		} else {
-			result = IP_CHECK_IF_FORWARD;
-			ip_input_setdst_chain(m, inifp->if_index, NULL);
-		}
-	}
-
-	if (result == IP_CHECK_IF_OURS && match_ifp != inifp) {
-		ipstat.ips_rcv_if_weak_match++;
-
-		/*  Logging is too noisy when forwarding is enabled */
-		if (ip_checkinterface_debug != 0 && ipforwarding == 0) {
-			char src_str[MAX_IPv4_STR_LEN];
-			char dst_str[MAX_IPv4_STR_LEN];
-
-			inet_ntop(AF_INET, &ip->ip_src, src_str, sizeof(src_str));
-			inet_ntop(AF_INET, &ip->ip_dst, dst_str, sizeof(dst_str));
-			os_log_info(OS_LOG_DEFAULT,
-			    "%s: weak ES interface match to %s for packet from %s to %s proto %u received via %s",
-			    __func__, best_ia->ia_ifp->if_xname, src_str, dst_str, ip->ip_p, inifp->if_xname);
-		}
-	} else if (result == IP_CHECK_IF_DROP) {
-		if (ip_checkinterface_debug > 0) {
-			char src_str[MAX_IPv4_STR_LEN];
-			char dst_str[MAX_IPv4_STR_LEN];
-
-			inet_ntop(AF_INET, &ip->ip_src, src_str, sizeof(src_str));
-			inet_ntop(AF_INET, &ip->ip_dst, dst_str, sizeof(dst_str));
-			if (drop_reason == DROP_REASON_IP_RCV_IF_NO_MATCH) {
-				os_log(OS_LOG_DEFAULT,
-				    "%s: no interface match for packet from %s to %s proto %u received via %s",
-				    __func__, src_str, dst_str, ip->ip_p, inifp->if_xname);
-			} else if (drop_reason == DROP_REASON_FSW_DEMUX_L2_MULTI_L3_UNI) {
-				os_log(OS_LOG_DEFAULT,
-				    "%s: Layer 3 unicast dst sent to layer 2 non unicast dst: from %s to %s proto %u received via %s",
-				    __func__, src_str, dst_str, ip->ip_p, inifp->if_xname);
-			}
-		}
-		if (drop_reason == DROP_REASON_IP_RCV_IF_NO_MATCH) {
-			mbuf_ref_t tmp_mbuf = m;
-			while (tmp_mbuf != NULL) {
-				ipstat.ips_rcv_if_no_match++;
-				tmp_mbuf = tmp_mbuf->m_nextpkt;
-			}
-		}
-		m_drop_list(m, NULL, DROPTAP_FLAG_DIR_IN | DROPTAP_FLAG_L2_MISSING, drop_reason, NULL, 0);
-		*mp = NULL;
-	}
-
-	return result;
-}
-
-static void
-ip_input_second_pass(struct mbuf *m, struct ifnet *inifp,
-    int npkts_in_chain, int bytes_in_chain, struct ip_fw_in_args *args)
-{
-	struct mbuf             *tmp_mbuf = NULL;
-	unsigned int            hlen;
-
-#pragma unused (args)
-
-	struct ip *__single ip = mtod(m, struct ip *);
-	hlen = IP_VHL_HL(ip->ip_vhl) << 2;
-
-	OSAddAtomic(npkts_in_chain, &ipstat.ips_total);
-
-	/*
-	 * Naively assume we can attribute inbound data to the route we would
-	 * use to send to this destination. Asymmetric 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.
-	 */
-	ip_input_update_nstat(inifp, ip->ip_src, npkts_in_chain,
-	    bytes_in_chain);
+	ip_nhops = 0;		/* for source routed packets */
+	if (hlen > sizeof (struct ip) && ip_dooptions(m, 0, args.next_hop, &ipforward_rt)) {
+		lck_mtx_unlock(ip_mutex);
+		return;
+	}
+
+        /* greedy RSVP, snatches any PATH packet of the RSVP protocol and no
+         * matter if it is destined to another node, or whether it is 
+         * a multicast one, RSVP wants it! and prevents it from being forwarded
+         * anywhere else. Also checks if the rsvp daemon is running before
+	 * grabbing the packet.
+         */
+	if (rsvp_on && ip->ip_p==IPPROTO_RSVP) 
+		goto ours;
 
 	/*
 	 * Check our list of addresses, to see if the packet is for us.
@@ -1538,23 +767,23 @@
 	 * we receive might be for us (and let the upper layers deal
 	 * with it).
 	 */
-	tmp_mbuf = m;
-	if (TAILQ_EMPTY(&in_ifaddrhead)) {
-		while (tmp_mbuf != NULL) {
-			if (!(tmp_mbuf->m_flags & (M_MCAST | M_BCAST))) {
-				ip_setdstifaddr_info(tmp_mbuf, inifp->if_index,
-				    NULL);
-			}
-			tmp_mbuf = mbuf_nextpkt(tmp_mbuf);
-		}
+	if (TAILQ_EMPTY(&in_ifaddrhead) &&
+	    (m->m_flags & (M_MCAST|M_BCAST)) == 0)
 		goto ours;
-	}
+
+	/*
+	 * Cache the destination address of the packet; this may be
+	 * changed by use of 'ipfw fwd'.
+	 */
+	pkt_dst = args.next_hop == NULL ?
+	    ip->ip_dst : args.next_hop->sin_addr;
 
 	/*
 	 * Enable a consistency check between the destination address
 	 * and the arrival interface for a unicast packet (the RFC 1122
 	 * strong ES model) if IP forwarding is disabled and the packet
-	 * is not locally generated
+	 * is not locally generated and the packet is not subject to
+	 * 'ipfw fwd'.
 	 *
 	 * XXX - Checking also should be disabled if the destination
 	 * address is ipnat'ed to a different interface.
@@ -1563,79 +792,311 @@
 	 * to the loopback interface instead of the interface where
 	 * the packets are received.
 	 */
-	if (!IN_MULTICAST(ntohl(ip->ip_dst.s_addr))) {
-		ip_check_if_result_t ip_check_if_result = IP_CHECK_IF_NONE;
-
-		ip_check_if_result = ip_input_check_interface(&m, ip, inifp);
-		ASSERT(ip_check_if_result != IP_CHECK_IF_NONE);
-		if (ip_check_if_result == IP_CHECK_IF_OURS) {
+	checkif = ip_checkinterface && (ipforwarding == 0) && 
+	    ((m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) == 0) &&
+	    (args.next_hop == NULL);
+
+	lck_mtx_lock(rt_mtx);
+	TAILQ_FOREACH(ia, &in_ifaddrhead, ia_link) {
+#define	satosin(sa)	((struct sockaddr_in *)(sa))
+
+		if (IA_SIN(ia)->sin_addr.s_addr == INADDR_ANY) {
+			lck_mtx_unlock(rt_mtx);
 			goto ours;
-		} else if (ip_check_if_result == IP_CHECK_IF_DROP) {
-			KERNEL_DEBUG(DBG_LAYER_END, 0, 0, 0, 0, 0);
-			return;
-		}
-	} else {
-		struct in_multi *__single inm;
+		}
+		
+		/*
+		 * If the address matches, verify that the packet
+		 * arrived via the correct interface if checking is
+		 * enabled.
+		 */
+		if (IA_SIN(ia)->sin_addr.s_addr == pkt_dst.s_addr && 
+		    (!checkif || ia->ia_ifp == m->m_pkthdr.rcvif)) {
+			lck_mtx_unlock(rt_mtx);
+			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 ((!checkif || ia->ia_ifp == m->m_pkthdr.rcvif) &&
+		    ia->ia_ifp && ia->ia_ifp->if_flags & IFF_BROADCAST) {
+			if (satosin(&ia->ia_broadaddr)->sin_addr.s_addr ==
+			    pkt_dst.s_addr) {
+				lck_mtx_unlock(rt_mtx);
+				goto ours;
+			}
+			if (ia->ia_netbroadcast.s_addr == pkt_dst.s_addr) {
+				lck_mtx_unlock(rt_mtx);
+				goto ours;
+			}
+		}
+	}
+	lck_mtx_unlock(rt_mtx);
+	if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr))) {
+		struct in_multi *inm;
+		if (ip_mrouter) {
+			/*
+			 * If we are acting as a multicast router, all
+			 * incoming multicast packets are passed to the
+			 * kernel-level multicast forwarding function.
+			 * The packet is returned (relatively) intact; if
+			 * ip_mforward() returns a non-zero value, the packet
+			 * must be discarded, else it may be accepted below.
+			 */
+			if (ip_mforward &&
+			    ip_mforward(ip, m->m_pkthdr.rcvif, m, 0) != 0) {
+				ipstat.ips_cantforward++;
+				m_freem(m);
+				lck_mtx_unlock(ip_mutex);
+				return;
+			}
+
+			/*
+			 * 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++;
+		}
 		/*
 		 * See if we belong to the destination multicast group on the
 		 * arrival interface.
 		 */
-		in_multihead_lock_shared();
-		IN_LOOKUP_MULTI(&ip->ip_dst, inifp, inm);
-		in_multihead_lock_done();
+		IN_LOOKUP_MULTI(ip->ip_dst, m->m_pkthdr.rcvif, inm);
 		if (inm == NULL) {
-			OSAddAtomic(npkts_in_chain, &ipstat.ips_notmember);
-			m_drop_list(m, NULL, DROPTAP_FLAG_DIR_IN | DROPTAP_FLAG_L2_MISSING, DROP_REASON_IP_UNKNOWN_MULTICAST_GROUP,
-			    NULL, 0);
-			KERNEL_DEBUG(DBG_LAYER_END, 0, 0, 0, 0, 0);
+			ipstat.ips_notmember++;
+			m_freem(m);
+			lck_mtx_unlock(ip_mutex);
 			return;
 		}
-		ip_input_setdst_chain(m, inifp->if_index, NULL);
-		INM_REMREF(inm);
 		goto ours;
 	}
-
-	tmp_mbuf = m;
-	struct mbuf *__single nxt_mbuf = NULL;
-	while (tmp_mbuf != NULL) {
-		nxt_mbuf = mbuf_nextpkt(tmp_mbuf);
+	if (ip->ip_dst.s_addr == (u_long)INADDR_BROADCAST)
+		goto ours;
+	if (ip->ip_dst.s_addr == INADDR_ANY)
+		goto ours;
+
+	/* Allow DHCP/BootP responses through */
+	if (m->m_pkthdr.rcvif != NULL
+	    && (m->m_pkthdr.rcvif->if_eflags & IFEF_AUTOCONFIGURING)
+	    && hlen == sizeof(struct ip)
+	    && ip->ip_p == IPPROTO_UDP) {
+		struct udpiphdr *ui;
+		if (m->m_len < sizeof(struct udpiphdr)
+		    && (m = m_pullup(m, sizeof(struct udpiphdr))) == 0) {
+			udpstat.udps_hdrops++;
+			lck_mtx_unlock(ip_mutex);
+			return;
+		}
+		ui = mtod(m, struct udpiphdr *);
+		if (ntohs(ui->ui_dport) == IPPORT_BOOTPC) {
+			goto ours;
+		}
+		ip = mtod(m, struct ip *); /* in case it changed */
+	}
+
+#if defined(NFAITH) && 0 < NFAITH
+	/*
+	 * FAITH(Firewall Aided Internet Translator)
+	 */
+	if (m->m_pkthdr.rcvif && m->m_pkthdr.rcvif->if_type == IFT_FAITH) {
+		if (ip_keepfaith) {
+			if (ip->ip_p == IPPROTO_TCP || ip->ip_p == IPPROTO_ICMP) 
+				goto ours;
+		}
+		m_freem(m);
+		lck_mtx_unlock(ip_mutex);
+		return;
+	}
+#endif
+	lck_mtx_unlock(ip_mutex);
+	/*
+	 * Not for us; forward if possible and desirable.
+	 */
+	if (ipforwarding == 0) {
+		ipstat.ips_cantforward++;
+		m_freem(m);
+	} else {
+		ip_forward(m, 0, args.next_hop, &ipforward_rt);
+	}
+	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.
+	 * (We could look in the reassembly queue to see
+	 * if the packet was previously fragmented,
+	 * but it's not worth the time; just let them time out.)
+	 */
+	if (ip->ip_off & (IP_MF | IP_OFFMASK | IP_RF)) {
+
+		/* If maxnipq is 0, never accept fragments. */
+		if (maxnipq == 0) {
+			ipstat.ips_fragments++;
+			ipstat.ips_fragdropped++;
+			goto bad;
+		}
+		
 		/*
-		 * Not for us; forward if possible and desirable.
+		 * If we will exceed the number of fragments in queues, timeout the
+		 * oldest fragemented packet to make space.
 		 */
-		mbuf_setnextpkt(tmp_mbuf, NULL);
-		if (ipforwarding == 0) {
-			OSAddAtomic(1, &ipstat.ips_cantforward);
-			m_drop(tmp_mbuf, DROPTAP_FLAG_DIR_IN | DROPTAP_FLAG_L2_MISSING, DROP_REASON_IP_CANNOT_FORWARD,
-			    NULL, 0);
+		if (currentfrags >= maxfrags) {
+			fp = TAILQ_LAST(&ipq_list, ipq_list);
+			ipstat.ips_fragtimeout += fp->ipq_nfrags;
+			
+			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.
+				 */
+				ipstat.ips_fragdropped++;
+				ip_freef(fp);
+				goto bad;
+			}
+			
+			ip_freef(fp);
+		}
+
+		sum = IPREASS_HASH(ip->ip_src.s_addr, ip->ip_id);
+		/*
+		 * Look for queue of fragments
+		 * of this datagram.
+		 */
+		for (fp = ipq[sum].next; fp != &ipq[sum]; fp = fp->next)
+			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)
+				goto found;
+
+		/*
+		 * 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 the oldest fragment before proceeding further
+		     */
+		    fp = TAILQ_LAST(&ipq_list, ipq_list);
+		    ipstat.ips_fragtimeout += fp->ipq_nfrags;
+		    ip_freef(fp);
+		}
+
+		fp = NULL;
+
+found:
+		/*
+		 * Adjust ip_len to not reflect header,
+		 * convert offset of this to bytes.
+		 */
+		ip->ip_len -= hlen;
+		if (ip->ip_off & IP_MF) {
+		        /*
+		         * Make sure that fragments have a data length
+				 * that's a non-zero multiple of 8 bytes.
+		         */
+			if (ip->ip_len == 0 || (ip->ip_len & 0x7) != 0) {
+				ipstat.ips_toosmall++; /* XXX */
+				goto bad;
+			}
+			m->m_flags |= M_FRAG;
 		} else {
-			ip_forward(tmp_mbuf, 0, NULL);
-		}
-		tmp_mbuf = nxt_mbuf;
-	}
-	KERNEL_DEBUG(DBG_LAYER_END, 0, 0, 0, 0, 0);
-	return;
-ours:
-	ip = mtod(m, struct ip *); /* in case it changed */
-	/*
-	 * If offset is set, must reassemble.
-	 */
-	if (ip->ip_off & ~(IP_DF | IP_RF)) {
-		VERIFY(npkts_in_chain == 1);
-		m = ip_reass(m);
-		if (m == NULL) {
-			KERNEL_DEBUG(DBG_LAYER_END, 0, 0, 0, 0, 0);
+			/* Clear the flag in case packet comes from loopback */
+			m->m_flags &= ~M_FRAG;
+		}
+		ip->ip_off <<= 3;
+
+		/*
+		 * 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.
+		 */
+			ipstat.ips_fragments++;
+			m->m_pkthdr.header = ip;
+#if IPDIVERT
+			m = ip_reass(m,
+			    fp, &ipq[sum], &div_info, &args.divert_rule);
+#else
+			m = ip_reass(m, fp, &ipq[sum]);
+#endif
+			if (m == 0) {
+				lck_mtx_unlock(ip_mutex);
+				return;
+			}
+			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 (div_info != 0) {
+				ip->ip_len += hlen;
+				HTONS(ip->ip_len);
+				HTONS(ip->ip_off);
+				ip->ip_sum = 0;
+				ip->ip_sum = in_cksum(m, hlen);
+				NTOHS(ip->ip_off);
+				NTOHS(ip->ip_len);
+				ip->ip_len -= hlen;
+			}
+#endif
+		} else
+		ip->ip_len -= hlen;
+
+#if IPDIVERT
+	/*
+	 * Divert or tee packet to the divert protocol if required.
+	 *
+	 * 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 (div_info != 0) {
+		struct mbuf *clone = NULL;
+
+		/* Clone packet if we're doing a 'tee' */
+		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;
+		HTONS(ip->ip_len);
+		HTONS(ip->ip_off);
+
+		/* Deliver packet to divert input routine */
+		ipstat.ips_delivered++;
+		lck_mtx_unlock(ip_mutex);
+		divert_packet(m, 1, div_info & 0xffff, args.divert_rule);
+
+		/* If 'tee', continue with original packet */
+		if (clone == NULL) {
 			return;
 		}
+		lck_mtx_lock(ip_mutex);
+		m = clone;
 		ip = mtod(m, struct ip *);
-		/* Get the header length of the reassembled packet */
-		hlen = IP_VHL_HL(ip->ip_vhl) << 2;
-	}
-
-	/*
-	 * Further protocols expect the packet length to be w/o the
-	 * IP header.
-	 */
-	ip->ip_len -= hlen;
+	}
+#endif
 
 #if IPSEC
 	/*
@@ -1643,194 +1104,59 @@
 	 * 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)) {
-		VERIFY(npkts_in_chain == 1);
+	if (ipsec_bypass == 0 && (ip_protox[ip->ip_p]->pr_flags & PR_LASTHDR) != 0) {
+		lck_mtx_lock(sadb_mutex);
 		if (ipsec4_in_reject(m, NULL)) {
-			IPSEC_STAT_INCREMENT(ipsecstat.in_polvio);
-			m_drop(tmp_mbuf, DROPTAP_FLAG_DIR_IN | DROPTAP_FLAG_L2_MISSING, DROP_REASON_IPSEC_REJECT,
-			    NULL, 0);
-			KERNEL_DEBUG(DBG_LAYER_END, 0, 0, 0, 0, 0);
-			return;
-		}
-	}
-#endif /* IPSEC */
+			ipsecstat.in_polvio++;
+			lck_mtx_unlock(sadb_mutex);
+			goto bad;
+		}
+		lck_mtx_unlock(sadb_mutex);
+	}
+#endif
 
 	/*
 	 * Switch out to protocol's input routine.
 	 */
-	OSAddAtomic(npkts_in_chain, &ipstat.ips_delivered);
-
-	ip_input_dispatch_chain(m);
-
-	KERNEL_DEBUG(DBG_LAYER_END, 0, 0, 0, 0, 0);
-	return;
-}
-
-void
-ip_proto_input(protocol_family_t protocol, mbuf_t packet_list)
-{
-#pragma unused(protocol)
-	pktchain_elm_t  pktchain_tbl[PKTTBL_SZ];
-
-	mbuf_ref_t packet = NULL;
-	mbuf_ref_t modm = NULL; /* modified mbuf */
-	int             retval = 0;
-#if (DEBUG || DEVELOPMENT)
-	struct timeval start_tv;
-#endif /* (DEBUG || DEVELOPMENT) */
-	int     num_pkts = 0;
-	int chain = 0;
-	struct ip_fw_in_args       args;
-
-#if (DEBUG || DEVELOPMENT)
-	if (ip_input_measure) {
-		net_perf_start_time(&net_perf, &start_tv);
-	}
-#endif /* (DEBUG || DEVELOPMENT) */
-
-	bzero(&pktchain_tbl, sizeof(pktchain_tbl));
-restart_list_process:
-	chain = 0;
-	for (packet = packet_list; packet; packet = packet_list) {
-		m_add_crumb(packet, PKT_CRUMB_IP_INPUT);
-
-		packet_list = mbuf_nextpkt(packet);
-		mbuf_setnextpkt(packet, NULL);
-
-		num_pkts++;
-		modm = NULL;
-		bzero(&args, sizeof(args));
-
-		retval = ip_input_first_pass(packet, &args, &modm);
-
-		if (retval == IPINPUT_DOCHAIN) {
-			if (modm) {
-				packet = modm;
-			}
-			packet = ip_chain_insert(packet, &pktchain_tbl[0]);
-			if (packet == NULL) {
-				ipstat.ips_rxc_chained++;
-				chain++;
-				if (chain > ip_chainsz) {
-					break;
-				}
-			} else {
-				ipstat.ips_rxc_collisions++;
-				break;
-			}
-		} else if (retval == IPINPUT_DONTCHAIN) {
-			/* in order to preserve order, exit from chaining */
-			if (modm) {
-				packet = modm;
-			}
-			ipstat.ips_rxc_notchain++;
-			break;
+	ipstat.ips_delivered++;
+	{
+		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_alloc(KERNEL_MODULE_TAG_ID, KERNEL_TAG_TYPE_IPFORWARD,
+					sizeof(struct sockaddr_in), M_NOWAIT);
+			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);
+	
+			lck_mtx_unlock(ip_mutex);
+	
+			/* TCP deals with its own locking */
+			ip_proto_dispatch_in(m, hlen, ip->ip_p, 0);
 		} else {
-			/* packet was freed or delivered, do nothing. */
-		}
-	}
-
-	/* do second pass here for pktchain_tbl */
-	if (chain) {
-		ip_input_second_pass_loop_tbl(&pktchain_tbl[0], &args);
-	}
-
-	if (packet) {
-		/*
-		 * equivalent update in chaining case if performed in
-		 * ip_input_second_pass_loop_tbl().
-		 */
-#if (DEBUG || DEVELOPMENT)
-		if (ip_input_measure) {
-			net_perf_histogram(&net_perf, 1);
-		}
-#endif /* (DEBUG || DEVELOPMENT) */
-		ip_input_second_pass(packet, packet->m_pkthdr.rcvif,
-		    1, packet->m_pkthdr.len, &args);
-	}
-
-	if (packet_list) {
-		goto restart_list_process;
-	}
-
-#if (DEBUG || DEVELOPMENT)
-	if (ip_input_measure) {
-		net_perf_measure_time(&net_perf, &start_tv, num_pkts);
-	}
-#endif /* (DEBUG || DEVELOPMENT) */
-}
-
-static void
-ipq_updateparams(void)
-{
-	LCK_MTX_ASSERT(&ipqlock, LCK_MTX_ASSERT_OWNED);
-	/*
-	 * -1 for unlimited allocation.
-	 */
-	if (maxnipq < 0) {
-		ipq_limit = 0;
-	}
-	/*
-	 * Positive number for specific bound.
-	 */
-	if (maxnipq > 0) {
-		ipq_limit = maxnipq;
-	}
-	/*
-	 * Zero specifies no further fragment queue allocation -- set the
-	 * bound very low, but rely on implementation elsewhere to actually
-	 * prevent allocation and reclaim current queues.
-	 */
-	if (maxnipq == 0) {
-		ipq_limit = 1;
-	}
-	/*
-	 * Arm the purge timer if not already and if there's work to do
-	 */
-	frag_sched_timeout();
-}
-
-static int
-sysctl_maxnipq SYSCTL_HANDLER_ARGS
-{
-#pragma unused(arg1, arg2)
-	int error, i;
-
-	lck_mtx_lock(&ipqlock);
-	i = maxnipq;
-	error = sysctl_handle_int(oidp, &i, 0, req);
-	if (error || req->newptr == USER_ADDR_NULL) {
-		goto done;
-	}
-	/* impose bounds */
-	if (i < -1) {
-		error = EINVAL;
-		goto done;
-	}
-	maxnipq = i;
-	ipq_updateparams();
-done:
-	lck_mtx_unlock(&ipqlock);
-	return error;
-}
-
-static int
-sysctl_maxfragsperpacket SYSCTL_HANDLER_ARGS
-{
-#pragma unused(arg1, arg2)
-	int error, i;
-
-	lck_mtx_lock(&ipqlock);
-	i = maxfragsperpacket;
-	error = sysctl_handle_int(oidp, &i, 0, req);
-	if (error || req->newptr == USER_ADDR_NULL) {
-		goto done;
-	}
-	maxfragsperpacket = i;
-	ipq_updateparams();     /* see if we need to arm timer */
-done:
-	lck_mtx_unlock(&ipqlock);
-	return error;
+			KERNEL_DEBUG(DBG_LAYER_END, ip->ip_dst.s_addr, 
+			     ip->ip_src.s_addr, ip->ip_p, ip->ip_off, ip->ip_len);
+		
+			lck_mtx_unlock(ip_mutex);
+			ip_proto_dispatch_in(m, hlen, ip->ip_p, 0);
+		}
+		
+		return;
+	}
+bad:
+	KERNEL_DEBUG(DBG_LAYER_END, 0,0,0,0,0);
+	lck_mtx_unlock(ip_mutex);
+	m_freem(m);
 }
 
 /*
@@ -1838,182 +1164,34 @@
  * whole datagram.  If a chain for reassembly of this datagram already
  * exists, then it is given as fp; otherwise have to make a chain.
  *
- * The IP header is *NOT* adjusted out of iplen (but in host byte order).
+ * When IPDIVERT enabled, keep additional state with each packet that
+ * tells us if we need to divert or tee the packet we're building.
  */
+
 static struct mbuf *
-ip_reass(struct mbuf *m)
+#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
+#ifdef IPDIVERT_44
+	u_int32_t *divinfo;
+#else
+	u_int16_t *divinfo;
+#endif
+	u_int16_t *divcookie;
+#endif
 {
-	struct ip *__single ip;
-	mbuf_ref_t p, q, nq, t;
-	struct ipq *__single fp = NULL;
-	struct ipqhead *__single head;
-	int i, hlen, next;
-	u_int8_t ecn, ecn0;
-	uint32_t csum, csum_flags;
-	uint16_t hash;
-	struct fq_head dfq;
-
-	MBUFQ_INIT(&dfq);       /* for deferred frees */
-
-	/* If maxnipq or maxfragsperpacket is 0, never accept fragments. */
-	if (maxnipq == 0 || maxfragsperpacket == 0) {
-		ipstat.ips_fragments++;
-		ipstat.ips_fragdropped++;
-		m_drop(m, DROPTAP_FLAG_DIR_IN | DROPTAP_FLAG_L2_MISSING, DROP_REASON_IP_FRAG_NOT_ACCEPTED,
-		    NULL, 0);
-		if (nipq > 0) {
-			lck_mtx_lock(&ipqlock);
-			frag_sched_timeout();   /* purge stale fragments */
-			lck_mtx_unlock(&ipqlock);
-		}
-		return NULL;
-	}
-
-	ip = mtod(m, struct ip *);
-	hlen = IP_VHL_HL(ip->ip_vhl) << 2;
-
-	lck_mtx_lock(&ipqlock);
-
-	hash = IPREASS_HASH(ip->ip_src.s_addr, ip->ip_id);
-	head = &ipq[hash];
-
-	/*
-	 * Look for queue of fragments
-	 * of this datagram.
-	 */
-	TAILQ_FOREACH(fp, head, ipq_list) {
-		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) {
-			goto found;
-		}
-	}
-
-	fp = NULL;
-
-	/*
-	 * Attempt to trim the number of allocated fragment queues if it
-	 * exceeds the administrative limit.
-	 */
-	if ((nipq > (unsigned)maxnipq) && (maxnipq > 0)) {
-		/*
-		 * drop something from the tail of the current queue
-		 * before proceeding further
-		 */
-		struct ipq *__single fq = TAILQ_LAST(head, ipqhead);
-		if (fq == NULL) {   /* gak */
-			for (i = 0; i < IPREASS_NHASH; i++) {
-				struct ipq *__single r = TAILQ_LAST(&ipq[i], ipqhead);
-				if (r) {
-					ipstat.ips_fragdropped += r->ipq_nfrags;
-					frag_freef(&ipq[i], r, DROP_REASON_IP_FRAG_TOO_MANY);
-					break;
-				}
-			}
-		} else {
-			ipstat.ips_fragdropped += fq->ipq_nfrags;
-			frag_freef(head, fq, DROP_REASON_IP_FRAG_TOO_MANY);
-		}
-	}
-
-found:
-	/*
-	 * Leverage partial checksum offload for IP fragments.  Narrow down
-	 * the scope to cover only UDP without IP options, as that is the
-	 * most common case.
-	 *
-	 * Perform 1's complement adjustment of octets that got included/
-	 * excluded in the hardware-calculated checksum value.  Ignore cases
-	 * where the value includes the entire IPv4 header span, as the sum
-	 * for those octets would already be 0 by the time we get here; IP
-	 * has already performed its header checksum validation.  Also take
-	 * care of any trailing bytes and subtract out their partial sum.
-	 */
-	if (ip->ip_p == IPPROTO_UDP && hlen == sizeof(struct ip) &&
-	    (m->m_pkthdr.csum_flags &
-	    (CSUM_DATA_VALID | CSUM_PARTIAL | CSUM_PSEUDO_HDR)) ==
-	    (CSUM_DATA_VALID | CSUM_PARTIAL)) {
-		uint32_t start = m->m_pkthdr.csum_rx_start;
-		int32_t trailer = (m_pktlen(m) - ip->ip_len);
-		uint32_t swbytes = (uint32_t)trailer;
-
-		csum = m->m_pkthdr.csum_rx_val;
-
-		ASSERT(trailer >= 0);
-		if ((start != 0 && start != hlen) || trailer != 0) {
-			uint32_t datalen = ip->ip_len - hlen;
-
-#if BYTE_ORDER != BIG_ENDIAN
-			if (start < hlen) {
-				HTONS(ip->ip_len);
-				HTONS(ip->ip_off);
-			}
-#endif /* BYTE_ORDER != BIG_ENDIAN */
-			/* callee folds in sum */
-			csum = m_adj_sum16(m, start, hlen, datalen, csum);
-			if (hlen > start) {
-				swbytes += (hlen - start);
-			} else {
-				swbytes += (start - hlen);
-			}
-#if BYTE_ORDER != BIG_ENDIAN
-			if (start < hlen) {
-				NTOHS(ip->ip_off);
-				NTOHS(ip->ip_len);
-			}
-#endif /* BYTE_ORDER != BIG_ENDIAN */
-		}
-		csum_flags = m->m_pkthdr.csum_flags;
-
-		if (swbytes != 0) {
-			udp_in_cksum_stats(swbytes);
-		}
-		if (trailer != 0) {
-			m_adj(m, -trailer);
-		}
-	} else {
-		csum = 0;
-		csum_flags = 0;
-	}
-
-	/* Invalidate checksum */
-	m->m_pkthdr.csum_flags &= ~CSUM_DATA_VALID;
-
-	ipstat.ips_fragments++;
-
-	/*
-	 * Adjust ip_len to not reflect header,
-	 * convert offset of this to bytes.
-	 */
-	ip->ip_len -= hlen;
-	if (ip->ip_off & IP_MF) {
-		/*
-		 * Make sure that fragments have a data length
-		 * that's a non-zero multiple of 8 bytes.
-		 */
-		if (ip->ip_len == 0 || (ip->ip_len & 0x7) != 0) {
-			OSAddAtomic(1, &ipstat.ips_toosmall);
-			/*
-			 * Reassembly queue may have been found if previous
-			 * fragments were valid; given that this one is bad,
-			 * we need to drop it.  Make sure to set fp to NULL
-			 * if not already, since we don't want to decrement
-			 * ipq_nfrags as it doesn't include this packet.
-			 */
-			fp = NULL;
-			goto dropfrag;
-		}
-		m->m_flags |= M_FRAG;
-	} else {
-		/* Clear the flag in case packet comes from loopback */
-		m->m_flags &= ~M_FRAG;
-	}
-	ip->ip_off = (u_short)(ip->ip_off << 3);
-
-	m->m_pkthdr.pkt_hdr = ip;
-
-	/* Previous ip_reass() started here. */
+	struct ip *ip = mtod(m, struct ip *);
+	register struct mbuf *p = 0, *q, *nq;
+	struct mbuf *t;
+	int hlen = IP_VHL_HL(ip->ip_vhl) << 2;
+	int i, next;
+
 	/*
 	 * Presence of header sizes in mbufs
 	 * would confuse code below.
@@ -2021,15 +1199,16 @@
 	m->m_data += hlen;
 	m->m_len -= hlen;
 
+	if (m->m_pkthdr.csum_flags & CSUM_TCP_SUM16) 
+               	m->m_pkthdr.csum_flags = 0;
 	/*
 	 * If first fragment to arrive, create a reassembly queue.
 	 */
-	if (fp == NULL) {
-		fp = ipq_alloc();
-		if (fp == NULL) {
+	if (fp == 0) {
+		if ((t = m_get(M_DONTWAIT, MT_FTABLE)) == NULL)
 			goto dropfrag;
-		}
-		TAILQ_INSERT_HEAD(head, fp, ipq_list);
+		fp = mtod(t, struct ipq *);
+		insque((void*)fp, (void*)where);
 		nipq++;
 		fp->ipq_nfrags = 1;
 		fp->ipq_ttl = IPFRAGTTL;
@@ -2039,49 +1218,28 @@
 		fp->ipq_dst = ip->ip_dst;
 		fp->ipq_frags = m;
 		m->m_nextpkt = NULL;
-		/*
-		 * If the first fragment has valid checksum offload
-		 * info, the rest of fragments are eligible as well.
-		 */
-		if (csum_flags != 0) {
-			fp->ipq_csum = csum;
-			fp->ipq_csum_flags = csum_flags;
-		}
-		m = NULL;       /* nothing to return */
-		goto done;
+#if IPDIVERT
+#ifdef IPDIVERT_44
+		fp->ipq_div_info = 0;
+#else
+		fp->ipq_divert = 0;
+#endif
+		fp->ipq_div_cookie = 0;
+#endif
+		TAILQ_INSERT_HEAD(&ipq_list, fp, ipq_list);
+		goto inserted;
 	} else {
 		fp->ipq_nfrags++;
 	}
 
-#define GETIP(m)        ((struct ip *)((m)->m_pkthdr.pkt_hdr))
-
-	/*
-	 * 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;
-	}
+#define GETIP(m)	((struct ip*)((m)->m_pkthdr.header))
 
 	/*
 	 * Find a segment which begins after this one does.
 	 */
-	for (p = NULL, q = fp->ipq_frags; q; p = q, q = q->m_nextpkt) {
-		if (GETIP(q)->ip_off > ip->ip_off) {
+	for (p = NULL, q = fp->ipq_frags; q; p = q, q = q->m_nextpkt)
+		if (GETIP(q)->ip_off > ip->ip_off)
 			break;
-		}
-	}
 
 	/*
 	 * If there is a preceding segment, it may provide some of
@@ -2089,17 +1247,16 @@
 	 * segment.  If it provides all of our data, drop us, otherwise
 	 * stick new segment in the proper place.
 	 *
-	 * If some of the data is dropped from the preceding
+	 * If some of the data is dropped from the the preceding
 	 * segment, then it's checksum is invalidated.
 	 */
 	if (p) {
 		i = GETIP(p)->ip_off + GETIP(p)->ip_len - ip->ip_off;
 		if (i > 0) {
-			if (i >= ip->ip_len) {
+			if (i >= ip->ip_len)
 				goto dropfrag;
-			}
 			m_adj(m, i);
-			fp->ipq_csum_flags = 0;
+			m->m_pkthdr.csum_flags = 0;
 			ip->ip_off += i;
 			ip->ip_len -= i;
 		}
@@ -2115,34 +1272,42 @@
 	 * if they are completely covered, dequeue them.
 	 */
 	for (; q != NULL && ip->ip_off + ip->ip_len > GETIP(q)->ip_off;
-	    q = nq) {
-		i = (ip->ip_off + ip->ip_len) - GETIP(q)->ip_off;
+	     q = nq) {
+		i = (ip->ip_off + ip->ip_len) -
+		    GETIP(q)->ip_off;
 		if (i < GETIP(q)->ip_len) {
 			GETIP(q)->ip_len -= i;
 			GETIP(q)->ip_off += i;
 			m_adj(q, i);
-			fp->ipq_csum_flags = 0;
+			q->m_pkthdr.csum_flags = 0;
 			break;
 		}
 		nq = q->m_nextpkt;
 		m->m_nextpkt = nq;
 		ipstat.ips_fragdropped++;
 		fp->ipq_nfrags--;
-		/* defer freeing until after lock is dropped */
-		MBUFQ_ENQUEUE(&dfq, q);
-	}
-
-	/*
-	 * If this fragment contains similar checksum offload info
-	 * as that of the existing ones, accumulate checksum.  Otherwise,
-	 * invalidate checksum offload info for the entire datagram.
-	 */
-	if (csum_flags != 0 && csum_flags == fp->ipq_csum_flags) {
-		fp->ipq_csum += csum;
-	} else if (fp->ipq_csum_flags != 0) {
-		fp->ipq_csum_flags = 0;
-	}
-
+		m_freem(q);
+	}
+
+inserted:
+	currentfrags++;
+
+#if IPDIVERT
+	/*
+	 * Transfer firewall instructions to the fragment structure.
+	 * 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 and perform frag per packet
@@ -2159,10 +1324,9 @@
 		if (GETIP(q)->ip_off != next) {
 			if (fp->ipq_nfrags > maxfragsperpacket) {
 				ipstat.ips_fragdropped += fp->ipq_nfrags;
-				frag_freef(head, fp, DROP_REASON_IP_FRAG_TOO_MANY);
-			}
-			m = NULL;       /* nothing to return */
-			goto done;
+				ip_freef(fp);
+			}
+			return (0);
 		}
 		next += GETIP(q)->ip_len;
 	}
@@ -2170,10 +1334,9 @@
 	if (p->m_flags & M_FRAG) {
 		if (fp->ipq_nfrags > maxfragsperpacket) {
 			ipstat.ips_fragdropped += fp->ipq_nfrags;
-			frag_freef(head, fp, DROP_REASON_IP_FRAG_TOO_MANY);
-		}
-		m = NULL;               /* nothing to return */
-		goto done;
+			ip_freef(fp);
+		}
+		return (0);
 	}
 
 	/*
@@ -2184,9 +1347,8 @@
 	if (next + (IP_VHL_HL(ip->ip_vhl) << 2) > IP_MAXPACKET) {
 		ipstat.ips_toolong++;
 		ipstat.ips_fragdropped += fp->ipq_nfrags;
-		frag_freef(head, fp, DROP_REASON_IP_FRAG_TOO_LONG);
-		m = NULL;               /* nothing to return */
-		goto done;
+		ip_freef(fp);
+		return (0);
 	}
 
 	/*
@@ -2194,97 +1356,70 @@
 	 */
 	m = q;
 	t = m->m_next;
-	m->m_next = NULL;
+	m->m_next = 0;
 	m_cat(m, t);
 	nq = q->m_nextpkt;
-	q->m_nextpkt = NULL;
+	q->m_nextpkt = 0;
 	for (q = nq; q != NULL; q = nq) {
 		nq = q->m_nextpkt;
 		q->m_nextpkt = NULL;
+		if (q->m_pkthdr.csum_flags & CSUM_TCP_SUM16) 
+	    		m->m_pkthdr.csum_flags = 0;
+		else {
+			m->m_pkthdr.csum_flags &= q->m_pkthdr.csum_flags;
+			m->m_pkthdr.csum_data += q->m_pkthdr.csum_data;
+		}
 		m_cat(m, q);
 	}
 
-	/*
-	 * Store partial hardware checksum info from the fragment queue;
-	 * the receive start offset is set to 20 bytes (see code at the
-	 * top of this routine.)
-	 */
-	if (fp->ipq_csum_flags != 0) {
-		csum = fp->ipq_csum;
-
-		ADDCARRY(csum);
-
-		m->m_pkthdr.csum_rx_val = (uint16_t)csum;
-		m->m_pkthdr.csum_rx_start = sizeof(struct ip);
-		m->m_pkthdr.csum_flags = fp->ipq_csum_flags;
-	} else if ((m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) ||
-	    (m->m_pkthdr.pkt_flags & PKTF_LOOP)) {
-		/* loopback checksums are always OK */
-		m->m_pkthdr.csum_data = 0xffff;
-		m->m_pkthdr.csum_flags =
-		    CSUM_DATA_VALID | CSUM_PSEUDO_HDR |
-		    CSUM_IP_CHECKED | CSUM_IP_VALID;
-	}
-
-	/*
-	 * Create header for new ip packet by modifying header of first
-	 * packet; dequeue and discard fragment reassembly header.
+#if IPDIVERT
+	/*
+	 * Extract firewall instructions from the fragment structure.
+	 */
+#ifdef IPDIVERT_44
+	*divinfo = fp->ipq_div_info;
+#else
+	*divinfo = fp->ipq_divert;
+#endif
+	*divcookie = fp->ipq_div_cookie;
+#endif
+
+	/*
+	 * Create header for new ip packet by
+	 * modifying header of first packet;
+	 * dequeue and discard fragment reassembly header.
 	 * Make header visible.
 	 */
-	ip->ip_len = (u_short)((IP_VHL_HL(ip->ip_vhl) << 2) + next);
+	ip->ip_len = next;
 	ip->ip_src = fp->ipq_src;
 	ip->ip_dst = fp->ipq_dst;
-
-	fp->ipq_frags = NULL;   /* return to caller as 'm' */
-	frag_freef(head, fp, DROP_REASON_UNSPECIFIED);
-	fp = NULL;
-
+	remque((void*)fp);
+	TAILQ_REMOVE(&ipq_list, fp, ipq_list);
+	currentfrags -= fp->ipq_nfrags;
+	nipq--;
+	(void) m_free(dtom(fp));
 	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 */
-		m_fixhdr(m);
-	}
-	ipstat.ips_reassembled++;
-
-	/* arm the purge timer if not already and if there's work to do */
-	frag_sched_timeout();
-	lck_mtx_unlock(&ipqlock);
-	/* perform deferred free (if needed) now that lock is dropped */
-	if (!MBUFQ_EMPTY(&dfq)) {
-		MBUFQ_DRAIN(&dfq);
-	}
-	VERIFY(MBUFQ_EMPTY(&dfq));
-	return m;
-
-done:
-	VERIFY(m == NULL);
-	/* arm the purge timer if not already and if there's work to do */
-	frag_sched_timeout();
-	lck_mtx_unlock(&ipqlock);
-	/* perform deferred free (if needed) */
-	if (!MBUFQ_EMPTY(&dfq)) {
-		MBUFQ_DRAIN(&dfq);
-	}
-	VERIFY(MBUFQ_EMPTY(&dfq));
-	return NULL;
+	if (m->m_flags & M_PKTHDR) { /* XXX this should be done elsewhere */
+		register int plen = 0;
+		for (t = m; t; t = t->m_next)
+			plen += t->m_len;
+		m->m_pkthdr.len = plen;
+	}
+	return (m);
 
 dropfrag:
+#if IPDIVERT
+	*divinfo = 0;
+	*divcookie = 0;
+#endif
 	ipstat.ips_fragdropped++;
-	if (fp != NULL) {
+	if (fp != 0)
 		fp->ipq_nfrags--;
-	}
-	/* arm the purge timer if not already and if there's work to do */
-	frag_sched_timeout();
-	lck_mtx_unlock(&ipqlock);
-	m_drop(m, DROPTAP_FLAG_DIR_IN | DROPTAP_FLAG_L2_MISSING, DROP_REASON_IP_FRAG_DROPPED,
-	    NULL, 0);
-	/* perform deferred free (if needed) */
-	if (!MBUFQ_EMPTY(&dfq)) {
-		MBUFQ_DRAIN(&dfq);
-	}
-	VERIFY(MBUFQ_EMPTY(&dfq));
-	return NULL;
+	m_freem(m);
+	return (0);
+
 #undef GETIP
 }
 
@@ -2293,51 +1428,38 @@
  * associated datagrams.
  */
 static void
-frag_freef(struct ipqhead *fhp, struct ipq *fp, drop_reason_t drop_reason)
+ip_freef(fp)
+	struct ipq *fp;
 {
-	LCK_MTX_ASSERT(&ipqlock, LCK_MTX_ASSERT_OWNED);
-
-	fp->ipq_nfrags = 0;
-	if (fp->ipq_frags != NULL) {
-		if (drop_reason == DROP_REASON_UNSPECIFIED) {
-			m_freem_list(fp->ipq_frags);
-		} else {
-			m_drop_list(fp->ipq_frags, NULL, DROPTAP_FLAG_DIR_IN | DROPTAP_FLAG_L2_MISSING, drop_reason, NULL, 0);
-		}
-		fp->ipq_frags = NULL;
-	}
-	TAILQ_REMOVE(fhp, fp, ipq_list);
+	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));
 	nipq--;
-	ipq_free(fp);
 }
 
 /*
- * IP reassembly timer processing
+ * IP timer processing;
+ * if a timer expires on a reassembly
+ * queue, discard it.
  */
-static void
-frag_timeout(void *arg)
+void
+ip_slowtimo()
 {
-#pragma unused(arg)
-	struct ipq *__single fp;
+	register struct ipq *fp;
 	int i;
-
-	/*
-	 * Update coarse-grained networking timestamp (in sec.); the idea
-	 * is to piggy-back on the timeout callout to update the counter
-	 * returnable via net_uptime().
-	 */
-	net_update_uptime();
-
-	lck_mtx_lock(&ipqlock);
+	lck_mtx_lock(ip_mutex);
 	for (i = 0; i < IPREASS_NHASH; i++) {
-		for (fp = TAILQ_FIRST(&ipq[i]); fp;) {
-			struct ipq *__single fpp;
-
-			fpp = fp;
-			fp = TAILQ_NEXT(fp, ipq_list);
-			if (--fpp->ipq_ttl == 0) {
-				ipstat.ips_fragtimeout += fpp->ipq_nfrags;
-				frag_freef(&ipq[i], fpp, DROP_REASON_IP_FRAG_TIMEOUT);
+		fp = ipq[i].next;
+		if (fp == 0)
+			continue;
+		while (fp != &ipq[i]) {
+			--fp->ipq_ttl;
+			fp = fp->next;
+			if (fp->prev->ipq_ttl == 0) {
+				ipstat.ips_fragtimeout += fp->prev->ipq_nfrags;
+				ip_freef(fp->prev);
 			}
 		}
 	}
@@ -2346,89 +1468,37 @@
 	 * (due to the limit being lowered), drain off
 	 * enough to get down to the new limit.
 	 */
-	if (maxnipq >= 0 && nipq > (unsigned)maxnipq) {
-		for (i = 0; i < IPREASS_NHASH; i++) {
-			while (nipq > (unsigned)maxnipq &&
-			    !TAILQ_EMPTY(&ipq[i])) {
+	if (maxnipq >= 0 && nipq > maxnipq) {
+	for (i = 0; i < IPREASS_NHASH; i++) {
+			while (nipq > maxnipq &&
+				(ipq[i].next != &ipq[i])) {
 				ipstat.ips_fragdropped +=
-				    TAILQ_FIRST(&ipq[i])->ipq_nfrags;
-				frag_freef(&ipq[i], TAILQ_FIRST(&ipq[i]), DROP_REASON_IP_FRAG_DROPPED);
-			}
-		}
-	}
-	/* re-arm the purge timer if there's work to do */
-	frag_timeout_run = 0;
-	frag_sched_timeout();
-	lck_mtx_unlock(&ipqlock);
-}
-
-static void
-frag_sched_timeout(void)
-{
-	LCK_MTX_ASSERT(&ipqlock, LCK_MTX_ASSERT_OWNED);
-
-	if (!frag_timeout_run && nipq > 0) {
-		frag_timeout_run = 1;
-		timeout(frag_timeout, NULL, hz);
-	}
+				    ipq[i].next->ipq_nfrags;
+				ip_freef(ipq[i].next);
+			}
+		}
+	}
+	ipflow_slowtimo();
+	lck_mtx_unlock(ip_mutex);
 }
 
 /*
  * Drain off all datagram fragments.
  */
-static void
-frag_drain(void)
+void
+ip_drain()
 {
-	int i;
-
-	lck_mtx_lock(&ipqlock);
+	int     i;
+
+	lck_mtx_lock(ip_mutex);
 	for (i = 0; i < IPREASS_NHASH; i++) {
-		while (!TAILQ_EMPTY(&ipq[i])) {
-			ipstat.ips_fragdropped +=
-			    TAILQ_FIRST(&ipq[i])->ipq_nfrags;
-			frag_freef(&ipq[i], TAILQ_FIRST(&ipq[i]), DROP_REASON_IP_FRAG_DRAINED);
-		}
-	}
-	lck_mtx_unlock(&ipqlock);
-}
-
-static struct ipq *
-ipq_alloc(void)
-{
-	struct ipq *__single fp;
-
-	/*
-	 * See comments in ipq_updateparams().  Keep the count separate
-	 * from nipq since the latter represents the elements already
-	 * in the reassembly queues.
-	 */
-	if (ipq_limit > 0 && ipq_count > ipq_limit) {
-		return NULL;
-	}
-
-	fp = kalloc_type(struct ipq, Z_NOWAIT | Z_ZERO);
-	if (fp != NULL) {
-		os_atomic_inc(&ipq_count, relaxed);
-	}
-	return fp;
-}
-
-static void
-ipq_free(struct ipq *fp)
-{
-	kfree_type(struct ipq, fp);
-	os_atomic_dec(&ipq_count, relaxed);
-}
-
-/*
- * Drain callback
- */
-void
-ip_drain(void)
-{
-	frag_drain();           /* fragments */
-	in_rtqdrain();          /* protocol cloned routes */
-	in_arpdrain(NULL);      /* cloned routes: ARP */
+		while (ipq[i].next != &ipq[i]) {
+			ipstat.ips_fragdropped += ipq[i].next->ipq_nfrags;
+			ip_freef(ipq[i].next);
+		}
+	}
+	lck_mtx_unlock(ip_mutex);
+	in_rtqdrain();
 }
 
 /*
@@ -2444,51 +1514,38 @@
  * 0 if the packet should be processed further.
  */
 static int
-ip_dooptions(struct mbuf *m, int pass, struct sockaddr_in *next_hop)
+ip_dooptions(struct mbuf *m, int pass, struct sockaddr_in *next_hop, struct route *ipforward_rt)
 {
-#pragma unused(pass)
-	struct ip *ip = mtod(m, struct ip *);
-	u_char *cp;
-	struct ip_timestamp *__single ipt;
-	struct in_ifaddr *__single ia;
-	int opt, optlen, cnt, off, type = ICMP_PARAMPROB, forward = 0;
-	uint8_t code = 0;
-	struct in_addr *__single sin, dst;
-	u_int32_t ntime;
-	struct sockaddr_in ipaddr = {
-		.sin_len = sizeof(ipaddr),
-		.sin_family = AF_INET,
-		.sin_port = 0,
-		.sin_addr = { .s_addr = 0 },
-		.sin_zero = { 0, }
-	};
-
-	/* Expect 32-bit aligned data pointer on strict-align platforms */
-	MBUF_STRICT_DATA_ALIGNMENT_CHECK_32(m);
+	register struct ip *ip = mtod(m, struct ip *);
+	register u_char *cp;
+	register struct ip_timestamp *ipt;
+	register struct in_ifaddr *ia;
+	int opt, optlen, cnt, off, code, type = ICMP_PARAMPROB, forward = 0;
+	struct in_addr *sin, dst;
+	n_time ntime;
 
 	dst = ip->ip_dst;
 	cp = (u_char *)(ip + 1);
-	cnt = (IP_VHL_HL(ip->ip_vhl) << 2) - sizeof(struct ip);
+	cnt = (IP_VHL_HL(ip->ip_vhl) << 2) - sizeof (struct ip);
 	for (; cnt > 0; cnt -= optlen, cp += optlen) {
 		opt = cp[IPOPT_OPTVAL];
-		if (opt == IPOPT_EOL) {
+		if (opt == IPOPT_EOL)
 			break;
-		}
-		if (opt == IPOPT_NOP) {
+		if (opt == IPOPT_NOP)
 			optlen = 1;
-		} else {
+		else {
 			if (cnt < IPOPT_OLEN + sizeof(*cp)) {
-				code = (uint8_t)(&cp[IPOPT_OLEN] - (u_char *)ip);
+				code = &cp[IPOPT_OLEN] - (u_char *)ip;
 				goto bad;
 			}
 			optlen = cp[IPOPT_OLEN];
-			if (optlen < IPOPT_OLEN + sizeof(*cp) ||
-			    optlen > cnt) {
-				code = (uint8_t)(&cp[IPOPT_OLEN] - (u_char *)ip);
+			if (optlen < IPOPT_OLEN + sizeof(*cp) || optlen > cnt) {
+				code = &cp[IPOPT_OLEN] - (u_char *)ip;
 				goto bad;
 			}
 		}
 		switch (opt) {
+
 		default:
 			break;
 
@@ -2504,41 +1561,41 @@
 		case IPOPT_LSRR:
 		case IPOPT_SSRR:
 			if (optlen < IPOPT_OFFSET + sizeof(*cp)) {
-				code = (uint8_t)(&cp[IPOPT_OLEN] - (u_char *)ip);
+				code = &cp[IPOPT_OLEN] - (u_char *)ip;
 				goto bad;
 			}
 			if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) {
-				code = (uint8_t)(&cp[IPOPT_OFFSET] - (u_char *)ip);
+				code = &cp[IPOPT_OFFSET] - (u_char *)ip;
 				goto bad;
 			}
 			ipaddr.sin_addr = ip->ip_dst;
-			ia = ifatoia(ifa_ifwithaddr(SA(&ipaddr)));
-			if (ia == NULL) {
+			ia = (struct in_ifaddr *)
+				ifa_ifwithaddr((struct sockaddr *)&ipaddr);
+			if (ia == 0) {
 				if (opt == IPOPT_SSRR) {
 					type = ICMP_UNREACH;
 					code = ICMP_UNREACH_SRCFAIL;
 					goto bad;
 				}
-				if (!ip_dosourceroute) {
+				if (!ip_dosourceroute)
 					goto nosourcerouting;
-				}
 				/*
 				 * Loose routing, and not at next destination
 				 * yet; nothing to do except forward.
 				 */
 				break;
-			} else {
-				ifa_remref(&ia->ia_ifa);
+			}
+			else {
+				ifafree(&ia->ia_ifa);
 				ia = NULL;
 			}
-			off--;                  /* 0 origin */
+			off--;			/* 0 origin */
 			if (off > optlen - (int)sizeof(struct in_addr)) {
 				/*
 				 * End of source route.  Should be for us.
 				 */
-				if (!ip_acceptsourceroute) {
+				if (!ip_acceptsourceroute)
 					goto nosourcerouting;
-				}
 				save_rte(cp, ip->ip_src);
 				break;
 			}
@@ -2552,53 +1609,46 @@
 					 */
 nosourcerouting:
 					log(LOG_WARNING,
-					    "attempted source route from %s "
-					    "to %s\n",
-					    inet_ntop(AF_INET, &ip->ip_src,
-					    buf, sizeof(buf)),
-					    inet_ntop(AF_INET, &ip->ip_dst,
-					    buf2, sizeof(buf2)));
+					    "attempted source route from %s to %s\n",
+					    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;
 				} else {
 					/*
-					 * Not acting as a router,
-					 * so silently drop.
+					 * Not acting as a router, so silently drop.
 					 */
-					OSAddAtomic(1, &ipstat.ips_cantforward);
-					m_drop(m, DROPTAP_FLAG_DIR_IN | DROPTAP_FLAG_L2_MISSING, DROP_REASON_IP_CANNOT_FORWARD,
-					    NULL, 0);
-					return 1;
+					ipstat.ips_cantforward++;
+					m_freem(m);
+					return (1);
 				}
 			}
 
 			/*
 			 * locate outgoing interface
 			 */
-			(void) memcpy(&ipaddr.sin_addr, cp + off,
+			(void)memcpy(&ipaddr.sin_addr, cp + off,
 			    sizeof(ipaddr.sin_addr));
 
 			if (opt == IPOPT_SSRR) {
-#define INA     struct in_ifaddr *
-				if ((ia = (INA)ifa_ifwithdstaddr(
-					    SA(&ipaddr))) == NULL) {
-					ia = (INA)ifa_ifwithnet(SA(&ipaddr));
+#define	INA	struct in_ifaddr *
+#define	SA	struct sockaddr *
+			    if ((ia = (INA)ifa_ifwithdstaddr((SA)&ipaddr)) == 0) {
+					ia = (INA)ifa_ifwithnet((SA)&ipaddr);
 				}
 			} else {
-				ia = ip_rtaddr(ipaddr.sin_addr);
-			}
-			if (ia == NULL) {
+				ia = ip_rtaddr(ipaddr.sin_addr, ipforward_rt);
+			}
+			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),
+			(void)memcpy(cp + off, &(IA_SIN(ia)->sin_addr),
 			    sizeof(struct in_addr));
-			IFA_UNLOCK(&ia->ia_ifa);
-			ifa_remref(&ia->ia_ifa);
+			ifafree(&ia->ia_ifa);
 			ia = NULL;
 			cp[IPOPT_OFFSET] += sizeof(struct in_addr);
 			/*
@@ -2609,194 +1659,124 @@
 
 		case IPOPT_RR:
 			if (optlen < IPOPT_OFFSET + sizeof(*cp)) {
-				code = (uint8_t)(&cp[IPOPT_OFFSET] - (u_char *)ip);
+				code = &cp[IPOPT_OFFSET] - (u_char *)ip;
 				goto bad;
 			}
 			if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) {
-				code = (uint8_t)(&cp[IPOPT_OFFSET] - (u_char *)ip);
+				code = &cp[IPOPT_OFFSET] - (u_char *)ip;
 				goto bad;
 			}
 			/*
 			 * If no space remains, ignore.
 			 */
-			off--;                  /* 0 origin */
-			if (off > optlen - (int)sizeof(struct in_addr)) {
+			off--;			/* 0 origin */
+			if (off > optlen - (int)sizeof(struct in_addr))
 				break;
-			}
-			(void) memcpy(&ipaddr.sin_addr, &ip->ip_dst,
+			(void)memcpy(&ipaddr.sin_addr, &ip->ip_dst,
 			    sizeof(ipaddr.sin_addr));
 			/*
 			 * locate outgoing interface; if we're the destination,
 			 * use the incoming interface (should be same).
 			 */
-			if ((ia = (INA)ifa_ifwithaddr(SA(&ipaddr))) == NULL) {
-				if ((ia = ip_rtaddr(ipaddr.sin_addr)) == NULL) {
+			if ((ia = (INA)ifa_ifwithaddr((SA)&ipaddr)) != 0) {
+				if ((ia = ip_rtaddr(ipaddr.sin_addr, ipforward_rt)) == 0) {
 					type = ICMP_UNREACH;
 					code = ICMP_UNREACH_HOST;
 					goto bad;
 				}
 			}
-			IFA_LOCK(&ia->ia_ifa);
-			(void) memcpy(cp + off, &(IA_SIN(ia)->sin_addr),
+			(void)memcpy(cp + off, &(IA_SIN(ia)->sin_addr),
 			    sizeof(struct in_addr));
-			IFA_UNLOCK(&ia->ia_ifa);
-			ifa_remref(&ia->ia_ifa);
+			ifafree(&ia->ia_ifa);
 			ia = NULL;
 			cp[IPOPT_OFFSET] += sizeof(struct in_addr);
 			break;
 
 		case IPOPT_TS:
-			code = (uint8_t)(cp - (u_char *)ip);
-			ipt = (struct ip_timestamp *)(void *)cp;
+			code = cp - (u_char *)ip;
+			ipt = (struct ip_timestamp *)cp;
 			if (ipt->ipt_len < 4 || ipt->ipt_len > 40) {
-				code = (uint8_t)((u_char *)&ipt->ipt_len -
-				    (u_char *)ip);
+				code = (u_char *)&ipt->ipt_len - (u_char *)ip;
 				goto bad;
 			}
 			if (ipt->ipt_ptr < 5) {
-				code = (uint8_t)((u_char *)&ipt->ipt_ptr -
-				    (u_char *)ip);
+				code = (u_char *)&ipt->ipt_ptr - (u_char *)ip;
 				goto bad;
 			}
 			if (ipt->ipt_ptr >
 			    ipt->ipt_len - (int)sizeof(int32_t)) {
 				if (++ipt->ipt_oflw == 0) {
-					code = (uint8_t)((u_char *)&ipt->ipt_ptr -
-					    (u_char *)ip);
+					code = (u_char *)&ipt->ipt_ptr -
+					    (u_char *)ip;
 					goto bad;
 				}
 				break;
 			}
-			sin = (struct in_addr *)(void *)(cp + ipt->ipt_ptr - 1);
+			sin = (struct in_addr *)(cp + ipt->ipt_ptr - 1);
 			switch (ipt->ipt_flg) {
+
 			case IPOPT_TS_TSONLY:
 				break;
 
 			case IPOPT_TS_TSANDADDR:
 				if (ipt->ipt_ptr - 1 + sizeof(n_time) +
 				    sizeof(struct in_addr) > ipt->ipt_len) {
-					code = (uint8_t)((u_char *)&ipt->ipt_ptr -
-					    (u_char *)ip);
+					code = (u_char *)&ipt->ipt_ptr -
+					    (u_char *)ip;
 					goto bad;
 				}
 				ipaddr.sin_addr = dst;
-				ia = (INA)ifaof_ifpforaddr(SA(&ipaddr),
-				    m->m_pkthdr.rcvif);
-				if (ia == NULL) {
+				ia = (INA)ifaof_ifpforaddr((SA)&ipaddr,
+							    m->m_pkthdr.rcvif);
+				if (ia == 0)
 					continue;
-				}
-				IFA_LOCK(&ia->ia_ifa);
-				(void) memcpy(sin, &IA_SIN(ia)->sin_addr,
+				(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);
+				ifafree(&ia->ia_ifa);
 				ia = NULL;
 				break;
 
 			case IPOPT_TS_PRESPEC:
 				if (ipt->ipt_ptr - 1 + sizeof(n_time) +
 				    sizeof(struct in_addr) > ipt->ipt_len) {
-					code = (uint8_t)((u_char *)&ipt->ipt_ptr -
-					    (u_char *)ip);
+					code = (u_char *)&ipt->ipt_ptr -
+					    (u_char *)ip;
 					goto bad;
 				}
-				(void) memcpy(&ipaddr.sin_addr, sin,
+				(void)memcpy(&ipaddr.sin_addr, sin,
 				    sizeof(struct in_addr));
-				if ((ia = ifatoia(ifa_ifwithaddr(
-					    SA(&ipaddr)))) == NULL) {
+				if ((ia = (struct in_ifaddr*)ifa_ifwithaddr((SA)&ipaddr)) == 0)
 					continue;
-				}
-				ifa_remref(&ia->ia_ifa);
+				ifafree(&ia->ia_ifa);
 				ia = NULL;
 				ipt->ipt_ptr += sizeof(struct in_addr);
 				break;
 
 			default:
 				/* XXX can't take &ipt->ipt_flg */
-				code = (uint8_t)((u_char *)&ipt->ipt_ptr -
-				    (u_char *)ip + 1);
+				code = (u_char *)&ipt->ipt_ptr -
+				    (u_char *)ip + 1;
 				goto bad;
 			}
 			ntime = iptime();
-			(void) memcpy(cp + ipt->ipt_ptr - 1, &ntime,
+			(void)memcpy(cp + ipt->ipt_ptr - 1, &ntime,
 			    sizeof(n_time));
 			ipt->ipt_ptr += sizeof(n_time);
 		}
 	}
 	if (forward && ipforwarding) {
-		ip_forward(m, 1, next_hop);
-		return 1;
-	}
-	return 0;
+		ip_forward(m, 1, next_hop, ipforward_rt);
+		return (1);
+	}
+	return (0);
 bad:
+	ip->ip_len -= IP_VHL_HL(ip->ip_vhl) << 2;   /* XXX icmp_error adds in hdr length */
+	lck_mtx_unlock(ip_mutex);
 	icmp_error(m, type, code, 0, 0);
-	OSAddAtomic(1, &ipstat.ips_badoptions);
-	return 1;
-}
-
-/*
- * Check for the presence of the IP Router Alert option [RFC2113]
- * in the header of an IPv4 datagram.
- *
- * This call is not intended for use from the forwarding path; it is here
- * so that protocol domains may check for the presence of the option.
- * Given how FreeBSD's IPv4 stack is currently structured, the Router Alert
- * option does not have much relevance to the implementation, though this
- * may change in future.
- * Router alert options SHOULD be passed if running in IPSTEALTH mode and
- * we are not the endpoint.
- * Length checks on individual options should already have been peformed
- * by ip_dooptions() therefore they are folded under DIAGNOSTIC here.
- *
- * Return zero if not present or options are invalid, non-zero if present.
- */
-int
-ip_checkrouteralert(struct mbuf *m)
-{
-	struct ip *ip = mtod(m, struct ip *);
-	u_char *cp;
-	int opt, optlen, cnt, found_ra;
-
-	found_ra = 0;
-	cp = (u_char *)(ip + 1);
-	cnt = (IP_VHL_HL(ip->ip_vhl) << 2) - sizeof(struct ip);
-	for (; cnt > 0; cnt -= optlen, cp += optlen) {
-		opt = cp[IPOPT_OPTVAL];
-		if (opt == IPOPT_EOL) {
-			break;
-		}
-		if (opt == IPOPT_NOP) {
-			optlen = 1;
-		} else {
-#ifdef DIAGNOSTIC
-			if (cnt < IPOPT_OLEN + sizeof(*cp)) {
-				break;
-			}
-#endif
-			optlen = cp[IPOPT_OLEN];
-#ifdef DIAGNOSTIC
-			if (optlen < IPOPT_OLEN + sizeof(*cp) || optlen > cnt) {
-				break;
-			}
-#endif
-		}
-		switch (opt) {
-		case IPOPT_RA:
-#ifdef DIAGNOSTIC
-			if (optlen != IPOPT_OFFSET + sizeof(uint16_t) ||
-			    (*((uint16_t *)(void *)&cp[IPOPT_OFFSET]) != 0)) {
-				break;
-			} else
-#endif
-			found_ra = 1;
-			break;
-		default:
-			break;
-		}
-	}
-
-	return found_ra;
+	lck_mtx_lock(ip_mutex);
+	ipstat.ips_badoptions++;
+	return (1);
 }
 
 /*
@@ -2804,52 +1784,56 @@
  * return internet address info of interface to be used to get there.
  */
 struct in_ifaddr *
-ip_rtaddr(struct in_addr dst)
+ip_rtaddr(dst, rt)
+	struct in_addr dst;
+	struct route *rt;
 {
-	struct sockaddr_in *__single sin;
-	struct ifaddr *__single rt_ifa;
-	struct route ro;
-
-	bzero(&ro, sizeof(ro));
-	sin = SIN(&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) {
-		ROUTE_RELEASE(&ro);
-		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);
-	ROUTE_RELEASE(&ro);
-
-	return ifatoia(rt_ifa);
+	register struct sockaddr_in *sin;
+
+	sin = (struct sockaddr_in *)&rt->ro_dst;
+
+	lck_mtx_lock(rt_mtx);
+	if (rt->ro_rt == 0 || dst.s_addr != sin->sin_addr.s_addr ||
+		rt->ro_rt->generation_id != route_generation) {
+		if (rt->ro_rt) {
+			rtfree_locked(rt->ro_rt);
+			rt->ro_rt = 0;
+		}
+		sin->sin_family = AF_INET;
+		sin->sin_len = sizeof(*sin);
+		sin->sin_addr = dst;
+
+		rtalloc_ign_locked(rt, RTF_PRCLONING);
+	}
+	if (rt->ro_rt == 0) {
+		lck_mtx_unlock(rt_mtx);
+		return ((struct in_ifaddr *)0);
+	}
+
+	if (rt->ro_rt->rt_ifa)
+		ifaref(rt->ro_rt->rt_ifa);
+	lck_mtx_unlock(rt_mtx);
+	return ((struct in_ifaddr *) rt->ro_rt->rt_ifa);
 }
 
 /*
  * Save incoming source route for use in replies,
  * to be picked up later by ip_srcroute if the receiver is interested.
  */
-static void
-save_rte(u_char *__indexable option, struct in_addr dst)
+void
+save_rte(option, dst)
+	u_char *option;
+	struct in_addr dst;
 {
 	unsigned olen;
 
 	olen = option[IPOPT_OLEN];
 #if DIAGNOSTIC
-	if (ipprintfs) {
+	if (ipprintfs)
 		printf("save_rte: olen %d\n", olen);
-	}
-#endif
-	if (olen > sizeof(ip_srcrt) - (1 + sizeof(dst))) {
+#endif
+	if (olen > sizeof(ip_srcrt) - (1 + sizeof(dst)))
 		return;
-	}
 	bcopy(option, ip_srcrt.srcopt, olen);
 	ip_nhops = (olen - IPOPT_OFFSET - 1) / sizeof(struct in_addr);
 	ip_srcrt.dst = dst;
@@ -2861,48 +1845,35 @@
  * The first hop is placed before the options, will be removed later.
  */
 struct mbuf *
-ip_srcroute(void)
+ip_srcroute()
 {
-	struct in_addr *p, *q;
-	struct mbuf *m;
-
-	if (ip_nhops == 0) {
-		return NULL;
-	}
-
+	register struct in_addr *p, *q;
+	register struct mbuf *m;
+
+	if (ip_nhops == 0)
+		return ((struct mbuf *)0);
 	m = m_get(M_DONTWAIT, MT_HEADER);
-	if (m == NULL) {
-		return NULL;
-	}
-
-#define OPTSIZ  (sizeof (ip_srcrt.nop) + sizeof (ip_srcrt.srcopt))
+	if (m == 0)
+		return ((struct mbuf *)0);
+
+#define OPTSIZ	(sizeof(ip_srcrt.nop) + sizeof(ip_srcrt.srcopt))
 
 	/* length is (nhops+1)*sizeof(addr) + sizeof(nop + srcrt header) */
-	m->m_len = ip_nhops * sizeof(struct in_addr) +
-	    sizeof(struct in_addr) + OPTSIZ;
+	m->m_len = ip_nhops * sizeof(struct in_addr) + sizeof(struct in_addr) +
+	    OPTSIZ;
 #if DIAGNOSTIC
-	if (ipprintfs) {
+	if (ipprintfs)
 		printf("ip_srcroute: nhops %d mlen %d", ip_nhops, m->m_len);
-	}
-#endif
-
-	/*
-	 * Notes: to the astute reader:
-	 * 1. The code is sequenced in the order
-	 *    of writing to the mbuf contents.
-	 * 2. The order of addresses in `ip_srcrt.route`
-	 *    is the reverse of the order in the wire format.
-	 */
+#endif
+
 	/*
 	 * First save first hop for return route
 	 */
 	p = &ip_srcrt.route[ip_nhops - 1];
-	*(mtod(m, struct in_addr *)) = *p;
+	*(mtod(m, struct in_addr *)) = *p--;
 #if DIAGNOSTIC
-	if (ipprintfs) {
-		printf(" hops %lx",
-		    (u_int32_t)ntohl(mtod(m, struct in_addr *)->s_addr));
-	}
+	if (ipprintfs)
+		printf(" hops %lx", (u_long)ntohl(mtod(m, struct in_addr *)->s_addr));
 #endif
 
 	/*
@@ -2910,182 +1881,68 @@
 	 */
 	ip_srcrt.nop = IPOPT_NOP;
 	ip_srcrt.srcopt[IPOPT_OFFSET] = IPOPT_MINOFF;
-	(void) __nochk_memcpy(mtod(m, caddr_t) + sizeof(struct in_addr),
-	    (caddr_t)&ip_srcrt + sizeof(struct in_addr), OPTSIZ);
-	q = (struct in_addr *)(void *)(mtod(m, caddr_t) +
+	(void)memcpy(mtod(m, caddr_t) + sizeof(struct in_addr),
+	    &ip_srcrt.nop, OPTSIZ);
+	q = (struct in_addr *)(mtod(m, caddr_t) +
 	    sizeof(struct in_addr) + OPTSIZ);
 #undef OPTSIZ
 	/*
-	 * If multiple return addresses were provided,
-	 * record the return path as an IP source route,
-	 * reversing the path.
-	 */
-	for (int i = 0; i < (ip_nhops - 1); i++) {
-		q[i] = ip_srcrt.route[ip_nhops - (i + 2)];
+	 * Record return path as an IP source route,
+	 * reversing the path (pointers are now aligned).
+	 */
+	while (p >= ip_srcrt.route) {
 #if DIAGNOSTIC
-		if (ipprintfs) {
-			printf(" %lx", (u_int32_t)ntohl(q[i].s_addr));
-		}
-#endif
+		if (ipprintfs)
+			printf(" %lx", (u_long)ntohl(q->s_addr));
+#endif
+		*q++ = *p--;
 	}
 	/*
 	 * Last hop goes to final destination.
 	 */
-	q[ip_nhops - 1] = ip_srcrt.dst;
+	*q = ip_srcrt.dst;
 #if DIAGNOSTIC
-	if (ipprintfs) {
-		printf(" %lx\n", (u_int32_t)ntohl(q[ip_nhops - 1].s_addr));
-	}
-#endif
-	return m;
+	if (ipprintfs)
+		printf(" %lx\n", (u_long)ntohl(q->s_addr));
+#endif
+	return (m);
 }
 
 /*
- * Strip out IP options, at higher level protocol in the kernel.
+ * Strip out IP options, at higher
+ * level protocol in the kernel.
+ * Second argument is buffer to which options
+ * will be moved, and return value is their length.
+ * XXX should be deleted; last arg currently ignored.
  */
 void
-ip_stripoptions(struct mbuf *m)
+ip_stripoptions(m, mopt)
+	register struct mbuf *m;
+	struct mbuf *mopt;
 {
-	int i;
+	register int i;
 	struct ip *ip = mtod(m, struct ip *);
-	caddr_t opts;
+	register caddr_t opts;
 	int olen;
 
-	/* Expect 32-bit aligned data pointer on strict-align platforms */
-	MBUF_STRICT_DATA_ALIGNMENT_CHECK_32(m);
-
-	/* use bcopy() since it supports overlapping range */
-	olen = (IP_VHL_HL(ip->ip_vhl) << 2) - sizeof(struct ip);
+	olen = (IP_VHL_HL(ip->ip_vhl) << 2) - sizeof (struct ip);
 	opts = (caddr_t)(ip + 1);
-	i = m->m_len - (sizeof(struct ip) + olen);
+	i = m->m_len - (sizeof (struct ip) + olen);
 	bcopy(opts + olen, opts, (unsigned)i);
 	m->m_len -= olen;
-	if (m->m_flags & M_PKTHDR) {
+	if (m->m_flags & M_PKTHDR)
 		m->m_pkthdr.len -= olen;
-	}
 	ip->ip_vhl = IP_MAKE_VHL(IPVERSION, sizeof(struct ip) >> 2);
-
-	/*
-	 * We expect ip_{off,len} to be in host order by now, and
-	 * that the original IP header length has been subtracted
-	 * out from ip_len.  Temporarily adjust ip_len for checksum
-	 * recalculation, and restore it afterwards.
-	 */
-	ip->ip_len += sizeof(struct ip);
-
-	/* recompute checksum now that IP header is smaller */
-#if BYTE_ORDER != BIG_ENDIAN
-	HTONS(ip->ip_len);
-	HTONS(ip->ip_off);
-#endif /* BYTE_ORDER != BIG_ENDIAN */
-	ip->ip_sum = in_cksum_hdr(ip);
-#if BYTE_ORDER != BIG_ENDIAN
-	NTOHS(ip->ip_off);
-	NTOHS(ip->ip_len);
-#endif /* BYTE_ORDER != BIG_ENDIAN */
-
-	ip->ip_len -= sizeof(struct ip);
-
-	/*
-	 * Given that we've just stripped IP options from the header,
-	 * we need to adjust the start offset accordingly if this
-	 * packet had gone thru partial checksum offload.
-	 */
-	if ((m->m_pkthdr.csum_flags & (CSUM_DATA_VALID | CSUM_PARTIAL)) ==
-	    (CSUM_DATA_VALID | CSUM_PARTIAL)) {
-		if (m->m_pkthdr.csum_rx_start >= (sizeof(struct ip) + olen)) {
-			/* most common case */
-			m->m_pkthdr.csum_rx_start -= olen;
-		} else {
-			/* compute checksum in software instead */
-			m->m_pkthdr.csum_flags &= ~CSUM_DATA_VALID;
-			m->m_pkthdr.csum_data = 0;
-			ipstat.ips_adj_hwcsum_clr++;
-		}
-	}
 }
 
 u_char inetctlerrmap[PRC_NCMDS] = {
-	0, 0, 0, 0,
-	0, EMSGSIZE, EHOSTDOWN, EHOSTUNREACH,
-	ENETUNREACH, EHOSTUNREACH, ECONNREFUSED, ECONNREFUSED,
-	EMSGSIZE, EHOSTUNREACH, 0, 0,
-	0, 0, EHOSTUNREACH, 0,
-	ENOPROTOOPT, ECONNREFUSED
+	0,		0,		0,		0,
+	0,		EMSGSIZE,	EHOSTDOWN,	EHOSTUNREACH,
+	EHOSTUNREACH,	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++) {
-			ifnet_ref_t ifp = ifindex2ifnet[i];
-			if (ifp != NULL) {
-				lck_mtx_lock(&ifp->if_cached_route_lock);
-				ROUTE_RELEASE(&ifp->if_fwd_route);
-				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
@@ -3102,88 +1959,71 @@
  * via a source route.
  */
 static void
-ip_forward(struct mbuf *m, int srcrt, struct sockaddr_in *next_hop)
+ip_forward(struct mbuf *m, int srcrt, struct sockaddr_in *next_hop, struct route *ipforward_rt)
 {
-#pragma unused(next_hop)
-	struct ip *__single ip = mtod(m, struct ip *);
-	struct sockaddr_in *__single sin;
-	rtentry_ref_t rt;
-	struct route fwd_rt;
+	register struct ip *ip = mtod(m, struct ip *);
+	register struct sockaddr_in *sin;
+	register struct rtentry *rt;
 	int error, type = 0, code = 0;
-	mbuf_ref_t mcopy;
+	struct mbuf *mcopy;
 	n_long dest;
 	struct in_addr pkt_dst;
-	u_int32_t nextmtu = 0, len;
-	struct ip_out_args ipoa;
-	struct ifnet *__single rcvifp = m->m_pkthdr.rcvif;
-
-	bzero(&ipoa, sizeof(ipoa));
-	ipoa.ipoa_boundif = IFSCOPE_NONE;
-	ipoa.ipoa_sotc = SO_TC_UNSPEC;
-	ipoa.ipoa_netsvctype = _NET_SERVICE_TYPE_UNSPEC;
-
+	struct ifnet *destifp;
 #if IPSEC
-	struct secpolicy *sp = NULL;
-	int ipsecerror;
-#endif /* IPSEC */
-#if PF
-	struct pf_mtag *pf_mtag;
-#endif /* PF */
+	struct ifnet dummyifp;
+#endif
 
 	dest = 0;
-	pkt_dst = ip->ip_dst;
+	/*
+	 * 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;
 
 #if DIAGNOSTIC
-	if (ipprintfs) {
+	if (ipprintfs)
 		printf("forward: src %lx dst %lx ttl %x\n",
-		    (u_int32_t)ip->ip_src.s_addr, (u_int32_t)pkt_dst.s_addr,
+		    (u_long)ip->ip_src.s_addr, (u_long)pkt_dst.s_addr,
 		    ip->ip_ttl);
-	}
-#endif
-
-	if (m->m_flags & (M_BCAST | M_MCAST) || !in_canforward(pkt_dst)) {
-		OSAddAtomic(1, &ipstat.ips_cantforward);
-		m_drop(m, DROPTAP_FLAG_DIR_IN | DROPTAP_FLAG_L2_MISSING, DROP_REASON_IP_CANNOT_FORWARD,
-		    NULL, 0);
+#endif
+
+
+	if (m->m_flags & (M_BCAST|M_MCAST) || in_canforward(pkt_dst) == 0) {
+		ipstat.ips_cantforward++;
+		m_freem(m);
 		return;
 	}
 #if IPSTEALTH
 	if (!ipstealth) {
-#endif /* IPSTEALTH */
-	if (ip->ip_ttl <= IPTTLDEC) {
-		icmp_error(m, ICMP_TIMXCEED, ICMP_TIMXCEED_INTRANS,
-		    dest, 0);
-		return;
-	}
+#endif
+		if (ip->ip_ttl <= IPTTLDEC) {
+			icmp_error(m, ICMP_TIMXCEED, ICMP_TIMXCEED_INTRANS,
+			    dest, 0);
+			return;
+		}
 #if IPSTEALTH
-}
-#endif /* IPSTEALTH */
-
-#if PF
-	pf_mtag = pf_find_mtag(m);
-	if (pf_mtag != NULL && pf_mtag->pftag_rtableid != IFSCOPE_NONE) {
-		ipoa.ipoa_boundif = pf_mtag->pftag_rtableid;
-		ipoa.ipoa_flags |= IPOAF_BOUND_IF;
-	}
-#endif /* PF */
-
-	ip_fwd_route_copyout(rcvifp, &fwd_rt);
-
-	sin = SIN(&fwd_rt.ro_dst);
-	if (ROUTE_UNUSABLE(&fwd_rt) || pkt_dst.s_addr != sin->sin_addr.s_addr) {
-		ROUTE_RELEASE(&fwd_rt);
-
+	}
+#endif
+
+	sin = (struct sockaddr_in *)&ipforward_rt->ro_dst;
+	if ((rt = ipforward_rt->ro_rt) == 0 ||
+	    pkt_dst.s_addr != sin->sin_addr.s_addr ||
+	    ipforward_rt->ro_rt->generation_id != route_generation) {
+		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 = pkt_dst;
 
-		rtalloc_scoped_ign(&fwd_rt, RTF_PRCLONING, ipoa.ipoa_boundif);
-		if (fwd_rt.ro_rt == NULL) {
+		rtalloc_ign(ipforward_rt, RTF_PRCLONING);
+		if (ipforward_rt->ro_rt == 0) {
 			icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_HOST, dest, 0);
-			goto done;
-		}
-	}
-	rt = fwd_rt.ro_rt;
+			return;
+		}
+		rt = ipforward_rt->ro_rt;
+	}
 
 	/*
 	 * Save the IP header and at most 8 bytes of the payload,
@@ -3195,7 +2035,8 @@
 	 * data in a cluster may change before we reach icmp_error().
 	 */
 	MGET(mcopy, M_DONTWAIT, m->m_type);
-	if (mcopy != NULL && m_dup_pkthdr(mcopy, m, M_DONTWAIT) == 0) {
+	if (mcopy != NULL) {
+		M_COPY_PKTHDR(mcopy, m);
 		mcopy->m_len = imin((IP_VHL_HL(ip->ip_vhl) << 2) + 8,
 		    (int)ip->ip_len);
 		m_copydata(m, 0, mcopy->m_len, mtod(mcopy, caddr_t));
@@ -3203,11 +2044,11 @@
 
 #if IPSTEALTH
 	if (!ipstealth) {
-#endif /* IPSTEALTH */
-	ip->ip_ttl -= IPTTLDEC;
+#endif
+		ip->ip_ttl -= IPTTLDEC;
 #if IPSTEALTH
-}
-#endif /* IPSTEALTH */
+	}
+#endif
 
 	/*
 	 * If forwarding packet using same interface that it came in on,
@@ -3217,88 +2058,77 @@
 	 * Also, don't send redirect if forwarding using a default route
 	 * or a route modified by a redirect.
 	 */
-	RT_LOCK_SPIN(rt);
+#define	satosin(sa)	((struct sockaddr_in *)(sa))
 	if (rt->rt_ifp == m->m_pkthdr.rcvif &&
-	    !(rt->rt_flags & (RTF_DYNAMIC | RTF_MODIFIED)) &&
-	    satosin(rt_key(rt))->sin_addr.s_addr != INADDR_ANY &&
-	    ipsendredirects && !srcrt && rt->rt_ifa != NULL) {
-		struct in_ifaddr *ia = ifatoia(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;
+	    (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 = 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_int32_t)dest);
-			}
-#endif
-		}
-		IFA_UNLOCK(&ia->ia_ifa);
-	}
-	RT_UNLOCK(rt);
-
-
-	/* Mark this packet as being forwarded from another interface */
-	m->m_pkthdr.pkt_flags |= PKTF_FORWARDED;
-	len = m_pktlen(m);
-
-	error = ip_output(m, NULL, &fwd_rt, IP_FORWARDING | IP_OUTARGS,
-	    NULL, &ipoa);
-
-	/* Refresh rt since the route could have changed while in IP */
-	rt = fwd_rt.ro_rt;
-
-	if (error != 0) {
-		OSAddAtomic(1, &ipstat.ips_cantforward);
-	} else {
-		/*
-		 * Increment stats on the source interface; the ones
-		 * for destination interface has been taken care of
-		 * during output above by virtue of PKTF_FORWARDED.
-		 */
-		rcvifp->if_fpackets++;
-		rcvifp->if_fbytes += len;
-
-		OSAddAtomic(1, &ipstat.ips_forward);
-		if (type != 0) {
-			OSAddAtomic(1, &ipstat.ips_redirectsent);
-		} else {
-			if (mcopy != NULL) {
-				/*
-				 * 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.
-				 */
+		    if (ipprintfs)
+		        printf("redirect (%d) to %lx\n", code, (u_long)dest);
+#endif
+		}
+	}
+
+    {
+	if (next_hop) {
+		/* Pass IPFORWARD info if available */
+		struct m_tag *tag;
+		struct ip_fwd_tag	*ipfwd_tag;
+		
+		tag = m_tag_alloc(KERNEL_MODULE_TAG_ID, KERNEL_TAG_TYPE_IPFORWARD,
+				sizeof(struct sockaddr_in), M_NOWAIT);
+		if (tag == NULL) {
+			error = ENOBUFS;
+			m_freem(m);
+			return;
+		}
+		
+		ipfwd_tag = (struct ip_fwd_tag *)(tag+1);
+		ipfwd_tag->next_hop = next_hop;
+
+		m_tag_prepend(m, tag);
+	}
+	error = ip_output_list(m, 0, (struct mbuf *)0, ipforward_rt, 
+			  IP_FORWARDING, 0);
+    }
+	if (error)
+		ipstat.ips_cantforward++;
+	else {
+		ipstat.ips_forward++;
+		if (type)
+			ipstat.ips_redirectsent++;
+		else {
+			if (mcopy) {
+				ipflow_create(ipforward_rt, mcopy);
 				m_freem(mcopy);
 			}
-			goto done;
-		}
-	}
-	if (mcopy == NULL) {
-		goto done;
-	}
+			return;
+		}
+	}
+	if (mcopy == NULL)
+		return;
+	destifp = NULL;
 
 	switch (error) {
-	case 0:                         /* forwarded, but need redirect */
+
+	case 0:				/* forwarded, but need redirect */
 		/* type, code set above */
 		break;
 
-	case ENETUNREACH:               /* shouldn't happen, checked above */
+	case ENETUNREACH:		/* shouldn't happen, checked above */
 	case EHOSTUNREACH:
 	case ENETDOWN:
 	case EHOSTDOWN:
@@ -3310,553 +2140,201 @@
 	case EMSGSIZE:
 		type = ICMP_UNREACH;
 		code = ICMP_UNREACH_NEEDFRAG;
-
-		if (rt == NULL) {
-			break;
-		} else {
-			RT_LOCK_SPIN(rt);
-			if (rt->rt_ifp != NULL) {
-				nextmtu = rt->rt_ifp->if_mtu;
-			}
-			RT_UNLOCK(rt);
-		}
-#ifdef IPSEC
-		if (ipsec_bypass) {
-			break;
-		}
-
+#ifndef IPSEC
+		if (ipforward_rt->ro_rt)
+			destifp = ipforward_rt->ro_rt->rt_ifp;
+#else
 		/*
 		 * If the packet is routed over IPsec tunnel, tell the
 		 * originator the tunnel MTU.
 		 *	tunnel MTU = if MTU - sizeof(IP) - ESP/AH hdrsiz
 		 * XXX quickhack!!!
 		 */
-		sp = ipsec4_getpolicybyaddr(mcopy, IPSEC_DIR_OUTBOUND,
-		    IP_FORWARDING, &ipsecerror);
-
-		if (sp == NULL) {
-			break;
-		}
-
-		/*
-		 * find the correct route for outer IPv4
-		 * header, compute tunnel MTU.
-		 */
-		nextmtu = 0;
-
-		if (sp->req != NULL &&
-		    sp->req->saidx.mode == IPSEC_MODE_TUNNEL) {
-			struct secasindex saidx;
-			struct secasvar *__single sav;
-			struct route *__single ro;
-			struct ip *__single ipm;
-			size_t ipsechdr;
-
-			/* count IPsec header size */
-			ipsechdr = ipsec_hdrsiz(sp);
-
-			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 = SIN(&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 = SIN(&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 = (struct route *)&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);
+		if (ipforward_rt->ro_rt) {
+			struct secpolicy *sp = NULL;
+			int ipsecerror;
+			int ipsechdr;
+			struct route *ro;
+
+			if (ipsec_bypass) {
+				destifp = ipforward_rt->ro_rt->rt_ifp;
+				ipstat.ips_cantfrag++;
+				break;
+			}
+			lck_mtx_lock(sadb_mutex);
+			sp = ipsec4_getpolicybyaddr(mcopy,
+						    IPSEC_DIR_OUTBOUND,
+			                            IP_FORWARDING,
+			                            &ipsecerror);
+
+			if (sp == NULL)
+				destifp = ipforward_rt->ro_rt->rt_ifp;
+			else {
+				/* count IPsec header size */
+				ipsechdr = ipsec4_hdrsiz(mcopy,
+							 IPSEC_DIR_OUTBOUND,
+							 NULL);
+
+				/*
+				 * 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;
 					}
 				}
-				key_freesav(sav, KEY_SADB_LOCKED);
-				lck_mtx_unlock(sadb_mutex);
-			}
-		}
-		key_freesp(sp, KEY_SADB_UNLOCKED);
-#endif /* IPSEC */
+
+				key_freesp(sp);
+			}
+			lck_mtx_unlock(sadb_mutex);
+		}
+#endif /*IPSEC*/
+		ipstat.ips_cantfrag++;
 		break;
 
 	case ENOBUFS:
-		/*
-		 * A router should not generate ICMP_SOURCEQUENCH as
-		 * required in RFC1812 Requirements for IP Version 4 Routers.
-		 * Source quench could be a big problem under DoS attacks,
-		 * or if the underlying interface is rate-limited.
-		 * Those who need source quench packets may re-enable them
-		 * via the net.inet.ip.sendsourcequench sysctl.
-		 */
-		if (ip_sendsourcequench == 0) {
-			m_freem(mcopy);
-			goto done;
-		} else {
-			type = ICMP_SOURCEQUENCH;
-			code = 0;
-		}
+		type = ICMP_SOURCEQUENCH;
+		code = 0;
 		break;
 
-	case EACCES:
+	case EACCES:			/* ipfw denied packet */
 		m_freem(mcopy);
-		goto done;
-	}
-
-	if (type == ICMP_UNREACH && code == ICMP_UNREACH_NEEDFRAG) {
-		OSAddAtomic(1, &ipstat.ips_cantfrag);
-	}
-
-	icmp_error(mcopy, type, code, dest, nextmtu);
-done:
-	ip_fwd_route_copyin(rcvifp, &fwd_rt);
+		return;
+	}
+	icmp_error(mcopy, type, code, dest, destifp);
 }
 
-int
-ip_savecontrol(struct inpcb *inp, struct mbuf **mp, struct ip *ip,
-    struct mbuf *m)
+void
+ip_savecontrol(
+	register struct inpcb *inp,
+	register struct mbuf **mp,
+	register struct ip *ip,
+	register struct mbuf *m)
 {
-	*mp = NULL;
 	if (inp->inp_socket->so_options & SO_TIMESTAMP) {
 		struct timeval tv;
 
-		getmicrotime(&tv);
-		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) {
-		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_socket->so_options & SO_TIMESTAMP_CONTINUOUS) {
-		uint64_t time;
-
-		time = mach_continuous_time();
-		mp = sbcreatecontrol_mbuf((caddr_t)&time, sizeof(time),
-		    SCM_TIMESTAMP_CONTINUOUS, SOL_SOCKET, mp);
-		if (*mp == NULL) {
-			goto no_mbufs;
-		}
-	}
-	if (inp->inp_socket->so_flags & SOF_RECV_TRAFFIC_CLASS) {
-		int tc = m_get_traffic_class(m);
-
-		mp = sbcreatecontrol_mbuf((caddr_t)&tc, sizeof(tc),
-		    SO_TRAFFIC_CLASS, SOL_SOCKET, mp);
-		if (*mp == NULL) {
-			goto no_mbufs;
-		}
-	}
-	if ((inp->inp_socket->so_flags & SOF_RECV_WAKE_PKT) &&
-	    (m->m_pkthdr.pkt_flags & PKTF_WAKE_PKT)) {
-		int flag = 1;
-
-		mp = sbcreatecontrol_mbuf((caddr_t)&flag, sizeof(flag),
-		    SO_RECV_WAKE_PKT, SOL_SOCKET, mp);
-		if (*mp == NULL) {
-			goto no_mbufs;
-		}
-	}
-
-	if (inp->inp_flags & INP_RECVDSTADDR || SOFLOW_ENABLED(inp->inp_socket)) {
-		mp = sbcreatecontrol_mbuf((caddr_t)&ip->ip_dst,
-		    sizeof(struct in_addr), IP_RECVDSTADDR, IPPROTO_IP, mp);
-		if (*mp == NULL) {
-			goto no_mbufs;
-		}
+		microtime(&tv);
+		*mp = sbcreatecontrol((caddr_t) &tv, sizeof(tv),
+			SCM_TIMESTAMP, SOL_SOCKET);
+		if (*mp)
+			mp = &(*mp)->m_next;
+	}
+	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;
 	}
 #ifdef notyet
-	/*
-	 * XXX
+	/* XXX
 	 * Moving these out of udp_input() made them even more broken
 	 * than they already were.
 	 */
 	/* options were tossed already */
 	if (inp->inp_flags & INP_RECVOPTS) {
-		mp = sbcreatecontrol_mbuf((caddr_t)opts_deleted_above,
-		    sizeof(struct in_addr), IP_RECVOPTS, IPPROTO_IP, mp);
-		if (*mp == NULL) {
-			goto no_mbufs;
-		}
+		*mp = sbcreatecontrol((caddr_t) opts_deleted_above,
+		    sizeof(struct in_addr), IP_RECVOPTS, IPPROTO_IP);
+		if (*mp)
+			mp = &(*mp)->m_next;
 	}
 	/* ip_srcroute doesn't do what we want here, need to fix */
 	if (inp->inp_flags & INP_RECVRETOPTS) {
-		mp = sbcreatecontrol_mbuf((caddr_t)ip_srcroute(),
-		    sizeof(struct in_addr), IP_RECVRETOPTS, IPPROTO_IP, mp);
-		if (*mp == NULL) {
-			goto no_mbufs;
-		}
-	}
-#endif /* notyet */
+		*mp = sbcreatecontrol((caddr_t) ip_srcroute(),
+		    sizeof(struct in_addr), IP_RECVRETOPTS, IPPROTO_IP);
+		if (*mp)
+			mp = &(*mp)->m_next;
+	}
+#endif
 	if (inp->inp_flags & INP_RECVIF) {
-		ifnet_ref_t ifp;
-		uint8_t sdlbuf[SOCK_MAXADDRLEN + 1];
-		struct sockaddr_dl *sdl2 = SDL(sdlbuf);
-
-		/*
-		 * Make sure to accomodate the largest possible
-		 * size of SA(if_lladdr)->sa_len.
-		 */
-		static_assert(sizeof(sdlbuf) == (SOCK_MAXADDRLEN + 1));
+		struct ifnet *ifp;
+		struct sdlbuf {
+			struct sockaddr_dl sdl;
+			u_char	pad[32];
+		} sdlbuf;
+		struct sockaddr_dl *sdp;
+		struct sockaddr_dl *sdl2 = &sdlbuf.sdl;
 
 		ifnet_head_lock_shared();
-		if ((ifp = m->m_pkthdr.rcvif) != NULL &&
-		    ifp->if_index && IF_INDEX_IN_RANGE(ifp->if_index)) {
-			struct ifaddr *__single ifa = ifnet_addrs[ifp->if_index - 1];
-			struct sockaddr_dl *sdp;
-
-			if (!ifa || !ifa->ifa_addr) {
-				goto makedummy;
-			}
-
-			IFA_LOCK_SPIN(ifa);
-			sdp = SDL(ifa->ifa_addr);
+		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);
 			/*
 			 * Change our mind and don't try copy.
 			 */
-			if (sdp->sdl_family != AF_LINK) {
-				IFA_UNLOCK(ifa);
+			if ((sdp->sdl_family != AF_LINK)
+			|| (sdp->sdl_len > sizeof(sdlbuf))) {
 				goto makedummy;
 			}
-			/* the above static_assert() ensures sdl_len fits in sdlbuf */
-			SOCKADDR_COPY(sdp, sdl2, sdp->sdl_len);
-			IFA_UNLOCK(ifa);
+			bcopy(sdp, sdl2, sdp->sdl_len);
 		} else {
-makedummy:
-			sdl2->sdl_len =
-			    offsetof(struct sockaddr_dl, sdl_data[0]);
+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;
 		}
 		ifnet_head_done();
-		mp = sbcreatecontrol_mbuf((caddr_t)SA_BYTES(sdl2), sdl2->sdl_len,
-		    IP_RECVIF, IPPROTO_IP, mp);
-		if (*mp == NULL) {
-			goto no_mbufs;
-		}
+		*mp = sbcreatecontrol((caddr_t) sdl2, sdl2->sdl_len,
+			IP_RECVIF, IPPROTO_IP);
+		if (*mp)
+			mp = &(*mp)->m_next;
 	}
 	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_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 != NULL && m->m_pkthdr.rcvif != NULL) ?
-		    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;
-		}
-	}
-	if (inp->inp_flags & INP_RECVTOS) {
-		mp = sbcreatecontrol_mbuf((caddr_t)&ip->ip_tos,
-		    sizeof(u_char), IP_RECVTOS, IPPROTO_IP, mp);
-		if (*mp == NULL) {
-			goto no_mbufs;
-		}
-	}
-	if (inp->inp_flags2 & INP2_RECV_LINK_ADDR_TYPE) {
-		int mode = IP_RECV_LINK_ADDR_UNICAST;
-
-		if (m->m_flags & M_BCAST) {
-			mode = IP_RECV_LINK_ADDR_BROADCAST;
-		} else if (m->m_flags & M_MCAST) {
-			mode = IP_RECV_LINK_ADDR_MULTICAST;
-		}
-
-		mp = sbcreatecontrol_mbuf((caddr_t)&mode,
-		    sizeof(int), IP_RECV_LINK_ADDR_TYPE, IPPROTO_IP, mp);
-		if (*mp == NULL) {
-			goto no_mbufs;
-		}
-	}
-	return 0;
-
-no_mbufs:
-	ipstat.ips_pktdropcntrl++;
-	return ENOBUFS;
+		*mp = sbcreatecontrol((caddr_t)&ip->ip_ttl, sizeof(ip->ip_ttl), IP_RECVTTL, IPPROTO_IP);
+		if (*mp) mp = &(*mp)->m_next;
+	}
 }
 
-static inline u_short
-ip_cksum(struct mbuf *m, int hlen)
+int
+ip_rsvp_init(struct socket *so)
 {
-	u_short sum;
-
-	if (m->m_pkthdr.csum_flags & CSUM_IP_CHECKED) {
-		sum = !(m->m_pkthdr.csum_flags & CSUM_IP_VALID);
-	} else if (!(m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) &&
-	    !(m->m_pkthdr.pkt_flags & PKTF_LOOP)) {
-		/*
-		 * The packet arrived on an interface which isn't capable
-		 * of performing IP header checksum; compute it now.
-		 */
-		sum = ip_cksum_hdr_in(m, hlen);
-	} else {
-		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 != 0) {
-		OSAddAtomic(1, &ipstat.ips_badsum);
-	}
-
-	return sum;
-}
-
-static int
-ip_getstat SYSCTL_HANDLER_ARGS
-{
-#pragma unused(oidp, arg1, arg2)
-	if (req->oldptr == USER_ADDR_NULL) {
-		req->oldlen = (size_t)sizeof(struct ipstat);
-	}
-
-	return SYSCTL_OUT(req, &ipstat, MIN(sizeof(ipstat), req->oldlen));
-}
-
-void
-ip_setsrcifaddr_info(struct mbuf *m, uint16_t src_idx, struct in_ifaddr *ia)
-{
-	VERIFY(m->m_flags & M_PKTHDR);
-
-	/*
-	 * If the source ifaddr is specified, pick up the information
-	 * from there; otherwise just grab the passed-in ifindex as the
-	 * caller may not have the ifaddr available.
-	 */
-	if (ia != NULL) {
-		m->m_pkthdr.pkt_flags |= PKTF_IFAINFO;
-		m->m_pkthdr.src_ifindex = ia->ia_ifp->if_index;
-	} else {
-		m->m_pkthdr.src_ifindex = src_idx;
-		if (src_idx != 0) {
-			m->m_pkthdr.pkt_flags |= PKTF_IFAINFO;
-		}
-	}
-}
-
-void
-ip_setdstifaddr_info(struct mbuf *m, uint16_t dst_idx, struct in_ifaddr *ia)
-{
-	VERIFY(m->m_flags & M_PKTHDR);
-
-	/*
-	 * If the destination ifaddr is specified, pick up the information
-	 * from there; otherwise just grab the passed-in ifindex as the
-	 * caller may not have the ifaddr available.
-	 */
-	if (ia != NULL) {
-		m->m_pkthdr.pkt_flags |= PKTF_IFAINFO;
-		m->m_pkthdr.dst_ifindex = ia->ia_ifp->if_index;
-	} else {
-		m->m_pkthdr.dst_ifindex = dst_idx;
-		if (dst_idx != 0) {
-			m->m_pkthdr.pkt_flags |= PKTF_IFAINFO;
-		}
-	}
-}
-
-int
-ip_getsrcifaddr_info(struct mbuf *m, uint32_t *src_idx, uint32_t *iaf)
-{
-	VERIFY(m->m_flags & M_PKTHDR);
-
-	if (!(m->m_pkthdr.pkt_flags & PKTF_IFAINFO)) {
-		return -1;
-	}
-
-	if (src_idx != NULL) {
-		*src_idx = m->m_pkthdr.src_ifindex;
-	}
-
-	if (iaf != NULL) {
-		*iaf = 0;
+	if (so->so_type != SOCK_RAW ||
+	    so->so_proto->pr_protocol != IPPROTO_RSVP)
+	  return EOPNOTSUPP;
+
+	if (ip_rsvpd != NULL)
+	  return EADDRINUSE;
+
+	ip_rsvpd = so;
+	/*
+	 * This may seem silly, but we need to be sure we don't over-increment
+	 * the RSVP counter, in case something slips up.
+	 */
+	if (!ip_rsvp_on) {
+		ip_rsvp_on = 1;
+		rsvp_on++;
 	}
 
 	return 0;
 }
 
 int
-ip_getdstifaddr_info(struct mbuf *m, uint32_t *dst_idx, uint32_t *iaf)
+ip_rsvp_done(void)
 {
-	VERIFY(m->m_flags & M_PKTHDR);
-
-	if (!(m->m_pkthdr.pkt_flags & PKTF_IFAINFO)) {
-		return -1;
-	}
-
-	if (dst_idx != NULL) {
-		*dst_idx = m->m_pkthdr.dst_ifindex;
-	}
-
-	if (iaf != NULL) {
-		*iaf = 0;
-	}
-
+	ip_rsvpd = NULL;
+	/*
+	 * This may seem silly, but we need to be sure we don't over-decrement
+	 * the RSVP counter, in case something slips up.
+	 */
+	if (ip_rsvp_on) {
+		ip_rsvp_on = 0;
+		rsvp_on--;
+	}
 	return 0;
 }
-
-/*
- * Protocol input handler for IPPROTO_GRE.
- */
-void
-gre_input(struct mbuf *m, int off)
-{
-	gre_input_func_t fn = gre_input_func;
-
-	/*
-	 * If there is a registered GRE input handler, pass mbuf to it.
-	 */
-	if (fn != NULL) {
-		lck_mtx_unlock(inet_domain_mutex);
-		m = fn(m, off, (mtod(m, struct ip *))->ip_p);
-		lck_mtx_lock(inet_domain_mutex);
-	}
-
-	/*
-	 * If no matching tunnel that is up is found, we inject
-	 * the mbuf to raw ip socket to see if anyone picks it up.
-	 */
-	if (m != NULL) {
-		rip_input(m, off);
-	}
-}
-
-/*
- * Private KPI for PPP/PPTP.
- */
-int
-ip_gre_register_input(gre_input_func_t fn)
-{
-	lck_mtx_lock(inet_domain_mutex);
-	gre_input_func = fn;
-	lck_mtx_unlock(inet_domain_mutex);
-
-	return 0;
-}
-
-#if (DEBUG || DEVELOPMENT)
-static int
-sysctl_reset_ip_input_stats SYSCTL_HANDLER_ARGS
-{
-#pragma unused(arg1, arg2)
-	int error, i;
-
-	i = ip_input_measure;
-	error = sysctl_handle_int(oidp, &i, 0, req);
-	if (error || req->newptr == USER_ADDR_NULL) {
-		goto done;
-	}
-	/* impose bounds */
-	if (i < 0 || i > 1) {
-		error = EINVAL;
-		goto done;
-	}
-	if (ip_input_measure != i && i == 1) {
-		net_perf_initialize(&net_perf, ip_input_measure_bins);
-	}
-	ip_input_measure = i;
-done:
-	return error;
-}
-
-static int
-sysctl_ip_input_measure_bins SYSCTL_HANDLER_ARGS
-{
-#pragma unused(arg1, arg2)
-	int error;
-	uint64_t i;
-
-	i = ip_input_measure_bins;
-	error = sysctl_handle_quad(oidp, &i, 0, req);
-	if (error || req->newptr == USER_ADDR_NULL) {
-		goto done;
-	}
-	/* validate data */
-	if (!net_perf_validate_bins(i)) {
-		error = EINVAL;
-		goto done;
-	}
-	ip_input_measure_bins = i;
-done:
-	return error;
-}
-
-static int
-sysctl_ip_input_getperf SYSCTL_HANDLER_ARGS
-{
-#pragma unused(oidp, arg1, arg2)
-	if (req->oldptr == USER_ADDR_NULL) {
-		req->oldlen = (size_t)sizeof(struct ipstat);
-	}
-
-	return SYSCTL_OUT(req, &net_perf, MIN(sizeof(net_perf), req->oldlen));
-}
-#endif /* (DEBUG || DEVELOPMENT) */
-
-static int
-sysctl_ip_checkinterface SYSCTL_HANDLER_ARGS
-{
-#pragma unused(arg1, arg2)
-	int error, i;
-
-	i = ip_checkinterface;
-	error = sysctl_handle_int(oidp, &i, 0, req);
-	if (error != 0 || req->newptr == USER_ADDR_NULL) {
-		return error;
-	}
-
-	switch (i) {
-	case IP_CHECKINTERFACE_WEAK_ES:
-	case IP_CHECKINTERFACE_HYBRID_ES:
-	case IP_CHECKINTERFACE_STRONG_ES:
-		if (ip_checkinterface != i) {
-			ip_checkinterface = i;
-			os_log(OS_LOG_DEFAULT, "%s: ip_checkinterface is now %d\n",
-			    __func__, ip_checkinterface);
-		}
-		break;
-	default:
-		error = EINVAL;
-		break;
-	}
-	return error;
-}