ip_input.c revision 1.301
1/*	$NetBSD: ip_input.c,v 1.301 2012/06/22 14:54:35 christos Exp $	*/
2
3/*
4 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the project nor the names of its contributors
16 *    may be used to endorse or promote products derived from this software
17 *    without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31
32/*-
33 * Copyright (c) 1998 The NetBSD Foundation, Inc.
34 * All rights reserved.
35 *
36 * This code is derived from software contributed to The NetBSD Foundation
37 * by Public Access Networks Corporation ("Panix").  It was developed under
38 * contract to Panix by Eric Haszlakiewicz and Thor Lancelot Simon.
39 *
40 * Redistribution and use in source and binary forms, with or without
41 * modification, are permitted provided that the following conditions
42 * are met:
43 * 1. Redistributions of source code must retain the above copyright
44 *    notice, this list of conditions and the following disclaimer.
45 * 2. Redistributions in binary form must reproduce the above copyright
46 *    notice, this list of conditions and the following disclaimer in the
47 *    documentation and/or other materials provided with the distribution.
48 *
49 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
50 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
51 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
52 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
53 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
54 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
55 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
56 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
57 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
58 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
59 * POSSIBILITY OF SUCH DAMAGE.
60 */
61
62/*
63 * Copyright (c) 1982, 1986, 1988, 1993
64 *	The Regents of the University of California.  All rights reserved.
65 *
66 * Redistribution and use in source and binary forms, with or without
67 * modification, are permitted provided that the following conditions
68 * are met:
69 * 1. Redistributions of source code must retain the above copyright
70 *    notice, this list of conditions and the following disclaimer.
71 * 2. Redistributions in binary form must reproduce the above copyright
72 *    notice, this list of conditions and the following disclaimer in the
73 *    documentation and/or other materials provided with the distribution.
74 * 3. Neither the name of the University nor the names of its contributors
75 *    may be used to endorse or promote products derived from this software
76 *    without specific prior written permission.
77 *
78 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
79 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
80 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
81 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
82 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
83 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
84 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
85 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
86 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
87 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
88 * SUCH DAMAGE.
89 *
90 *	@(#)ip_input.c	8.2 (Berkeley) 1/4/94
91 */
92
93#include <sys/cdefs.h>
94__KERNEL_RCSID(0, "$NetBSD: ip_input.c,v 1.301 2012/06/22 14:54:35 christos Exp $");
95
96#include "opt_inet.h"
97#include "opt_compat_netbsd.h"
98#include "opt_gateway.h"
99#include "opt_pfil_hooks.h"
100#include "opt_ipsec.h"
101#include "opt_mrouting.h"
102#include "opt_mbuftrace.h"
103#include "opt_inet_csum.h"
104
105#include <sys/param.h>
106#include <sys/systm.h>
107#include <sys/mbuf.h>
108#include <sys/domain.h>
109#include <sys/protosw.h>
110#include <sys/socket.h>
111#include <sys/socketvar.h>
112#include <sys/errno.h>
113#include <sys/time.h>
114#include <sys/kernel.h>
115#include <sys/pool.h>
116#include <sys/sysctl.h>
117#include <sys/kauth.h>
118
119#include <net/if.h>
120#include <net/if_dl.h>
121#include <net/route.h>
122#include <net/pfil.h>
123
124#include <netinet/in.h>
125#include <netinet/in_systm.h>
126#include <netinet/ip.h>
127#include <netinet/in_pcb.h>
128#include <netinet/in_proto.h>
129#include <netinet/in_var.h>
130#include <netinet/ip_var.h>
131#include <netinet/ip_private.h>
132#include <netinet/ip_icmp.h>
133/* just for gif_ttl */
134#include <netinet/in_gif.h>
135#include "gif.h"
136#include <net/if_gre.h>
137#include "gre.h"
138
139#ifdef MROUTING
140#include <netinet/ip_mroute.h>
141#endif
142#include <netinet/rfc6056.h>
143
144#ifdef FAST_IPSEC
145#include <netipsec/ipsec.h>
146#include <netipsec/key.h>
147#endif	/* FAST_IPSEC*/
148
149#ifndef	IPFORWARDING
150#ifdef GATEWAY
151#define	IPFORWARDING	1	/* forward IP packets not for us */
152#else /* GATEWAY */
153#define	IPFORWARDING	0	/* don't forward IP packets not for us */
154#endif /* GATEWAY */
155#endif /* IPFORWARDING */
156#ifndef	IPSENDREDIRECTS
157#define	IPSENDREDIRECTS	1
158#endif
159#ifndef IPFORWSRCRT
160#define	IPFORWSRCRT	1	/* forward source-routed packets */
161#endif
162#ifndef IPALLOWSRCRT
163#define	IPALLOWSRCRT	1	/* allow source-routed packets */
164#endif
165#ifndef IPMTUDISC
166#define IPMTUDISC	1
167#endif
168#ifndef IPMTUDISCTIMEOUT
169#define IPMTUDISCTIMEOUT (10 * 60)	/* as per RFC 1191 */
170#endif
171
172#ifdef COMPAT_50
173#include <compat/sys/time.h>
174#include <compat/sys/socket.h>
175#endif
176
177/*
178 * Note: DIRECTED_BROADCAST is handled this way so that previous
179 * configuration using this option will Just Work.
180 */
181#ifndef IPDIRECTEDBCAST
182#ifdef DIRECTED_BROADCAST
183#define IPDIRECTEDBCAST	1
184#else
185#define	IPDIRECTEDBCAST	0
186#endif /* DIRECTED_BROADCAST */
187#endif /* IPDIRECTEDBCAST */
188int	ipforwarding = IPFORWARDING;
189int	ipsendredirects = IPSENDREDIRECTS;
190int	ip_defttl = IPDEFTTL;
191int	ip_forwsrcrt = IPFORWSRCRT;
192int	ip_directedbcast = IPDIRECTEDBCAST;
193int	ip_allowsrcrt = IPALLOWSRCRT;
194int	ip_mtudisc = IPMTUDISC;
195int	ip_mtudisc_timeout = IPMTUDISCTIMEOUT;
196#ifdef DIAGNOSTIC
197int	ipprintfs = 0;
198#endif
199
200int	ip_do_randomid = 0;
201
202/*
203 * XXX - Setting ip_checkinterface mostly implements the receive side of
204 * the Strong ES model described in RFC 1122, but since the routing table
205 * and transmit implementation do not implement the Strong ES model,
206 * setting this to 1 results in an odd hybrid.
207 *
208 * XXX - ip_checkinterface currently must be disabled if you use ipnat
209 * to translate the destination address to another local interface.
210 *
211 * XXX - ip_checkinterface must be disabled if you add IP aliases
212 * to the loopback interface instead of the interface where the
213 * packets for those addresses are received.
214 */
215int	ip_checkinterface = 0;
216
217
218struct rttimer_queue *ip_mtudisc_timeout_q = NULL;
219
220u_long	in_ifaddrhash;				/* size of hash table - 1 */
221int	in_ifaddrentries;			/* total number of addrs */
222struct in_ifaddrhead in_ifaddrhead;
223struct	in_ifaddrhashhead *in_ifaddrhashtbl;
224u_long	in_multihash;				/* size of hash table - 1 */
225int	in_multientries;			/* total number of addrs */
226struct	in_multihashhead *in_multihashtbl;
227struct	ifqueue ipintrq;
228
229ipid_state_t *		ip_ids;
230uint16_t ip_id;
231
232percpu_t *ipstat_percpu;
233
234#ifdef PFIL_HOOKS
235struct pfil_head inet_pfil_hook;
236#endif
237
238struct pool inmulti_pool;
239
240#ifdef INET_CSUM_COUNTERS
241#include <sys/device.h>
242
243struct evcnt ip_hwcsum_bad = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
244    NULL, "inet", "hwcsum bad");
245struct evcnt ip_hwcsum_ok = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
246    NULL, "inet", "hwcsum ok");
247struct evcnt ip_swcsum = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
248    NULL, "inet", "swcsum");
249
250#define	INET_CSUM_COUNTER_INCR(ev)	(ev)->ev_count++
251
252EVCNT_ATTACH_STATIC(ip_hwcsum_bad);
253EVCNT_ATTACH_STATIC(ip_hwcsum_ok);
254EVCNT_ATTACH_STATIC(ip_swcsum);
255
256#else
257
258#define	INET_CSUM_COUNTER_INCR(ev)	/* nothing */
259
260#endif /* INET_CSUM_COUNTERS */
261
262/*
263 * We need to save the IP options in case a protocol wants to respond
264 * to an incoming packet over the same route if the packet got here
265 * using IP source routing.  This allows connection establishment and
266 * maintenance when the remote end is on a network that is not known
267 * to us.
268 */
269int	ip_nhops = 0;
270static	struct ip_srcrt {
271	struct	in_addr dst;			/* final destination */
272	char	nop;				/* one NOP to align */
273	char	srcopt[IPOPT_OFFSET + 1];	/* OPTVAL, OLEN and OFFSET */
274	struct	in_addr route[MAX_IPOPTLEN/sizeof(struct in_addr)];
275} ip_srcrt;
276
277static int ip_drainwanted;
278
279static void save_rte(u_char *, struct in_addr);
280
281#ifdef MBUFTRACE
282struct mowner ip_rx_mowner = MOWNER_INIT("internet", "rx");
283struct mowner ip_tx_mowner = MOWNER_INIT("internet", "tx");
284#endif
285
286static void sysctl_net_inet_ip_setup(struct sysctllog **);
287
288/*
289 * IP initialization: fill in IP protocol switch table.
290 * All protocols not implemented in kernel go to raw IP protocol handler.
291 */
292void
293ip_init(void)
294{
295	const struct protosw *pr;
296	int i;
297
298	sysctl_net_inet_ip_setup(NULL);
299
300	pool_init(&inmulti_pool, sizeof(struct in_multi), 0, 0, 0, "inmltpl",
301	    NULL, IPL_SOFTNET);
302
303	pr = pffindproto(PF_INET, IPPROTO_RAW, SOCK_RAW);
304	if (pr == 0)
305		panic("ip_init");
306	for (i = 0; i < IPPROTO_MAX; i++)
307		ip_protox[i] = pr - inetsw;
308	for (pr = inetdomain.dom_protosw;
309	    pr < inetdomain.dom_protoswNPROTOSW; pr++)
310		if (pr->pr_domain->dom_family == PF_INET &&
311		    pr->pr_protocol && pr->pr_protocol != IPPROTO_RAW)
312			ip_protox[pr->pr_protocol] = pr - inetsw;
313
314	ip_reass_init();
315
316	ip_ids = ip_id_init();
317	ip_id = time_second & 0xfffff;
318
319	ipintrq.ifq_maxlen = IFQ_MAXLEN;
320
321	TAILQ_INIT(&in_ifaddrhead);
322	in_ifaddrhashtbl = hashinit(IN_IFADDR_HASH_SIZE, HASH_LIST, true,
323	    &in_ifaddrhash);
324	in_multihashtbl = hashinit(IN_IFADDR_HASH_SIZE, HASH_LIST, true,
325	    &in_multihash);
326	ip_mtudisc_timeout_q = rt_timer_queue_create(ip_mtudisc_timeout);
327#ifdef GATEWAY
328	ipflow_init(ip_hashsize);
329#endif
330
331#ifdef PFIL_HOOKS
332	/* Register our Packet Filter hook. */
333	inet_pfil_hook.ph_type = PFIL_TYPE_AF;
334	inet_pfil_hook.ph_af   = AF_INET;
335	i = pfil_head_register(&inet_pfil_hook);
336	if (i != 0)
337		printf("ip_init: WARNING: unable to register pfil hook, "
338		    "error %d\n", i);
339#endif /* PFIL_HOOKS */
340
341#ifdef MBUFTRACE
342	MOWNER_ATTACH(&ip_tx_mowner);
343	MOWNER_ATTACH(&ip_rx_mowner);
344#endif /* MBUFTRACE */
345
346	ipstat_percpu = percpu_alloc(sizeof(uint64_t) * IP_NSTATS);
347}
348
349struct	sockaddr_in ipaddr = {
350	.sin_len = sizeof(ipaddr),
351	.sin_family = AF_INET,
352};
353struct	route ipforward_rt;
354
355/*
356 * IP software interrupt routine
357 */
358void
359ipintr(void)
360{
361	int s;
362	struct mbuf *m;
363	struct ifqueue lcl_intrq;
364
365	memset(&lcl_intrq, 0, sizeof(lcl_intrq));
366
367	mutex_enter(softnet_lock);
368	KERNEL_LOCK(1, NULL);
369	if (!IF_IS_EMPTY(&ipintrq)) {
370		s = splnet();
371
372		/* Take existing queue onto stack */
373		lcl_intrq = ipintrq;
374
375		/* Zero out global queue, preserving maxlen and drops */
376		ipintrq.ifq_head = NULL;
377		ipintrq.ifq_tail = NULL;
378		ipintrq.ifq_len = 0;
379		ipintrq.ifq_maxlen = lcl_intrq.ifq_maxlen;
380		ipintrq.ifq_drops = lcl_intrq.ifq_drops;
381
382		splx(s);
383	}
384	KERNEL_UNLOCK_ONE(NULL);
385	while (!IF_IS_EMPTY(&lcl_intrq)) {
386		IF_DEQUEUE(&lcl_intrq, m);
387		if (m == NULL)
388			break;
389		ip_input(m);
390	}
391	mutex_exit(softnet_lock);
392}
393
394/*
395 * Ip input routine.  Checksum and byte swap header.  If fragmented
396 * try to reassemble.  Process options.  Pass to next level.
397 */
398void
399ip_input(struct mbuf *m)
400{
401	struct ip *ip = NULL;
402	struct in_ifaddr *ia;
403	struct ifaddr *ifa;
404	int hlen = 0, len;
405	int downmatch;
406	int checkif;
407	int srcrt = 0;
408#ifdef FAST_IPSEC
409	struct m_tag *mtag;
410	struct tdb_ident *tdbi;
411	struct secpolicy *sp;
412	int error, s;
413#endif /* FAST_IPSEC */
414
415	MCLAIM(m, &ip_rx_mowner);
416	KASSERT((m->m_flags & M_PKTHDR) != 0);
417
418	/*
419	 * If no IP addresses have been set yet but the interfaces
420	 * are receiving, can't do anything with incoming packets yet.
421	 */
422	if (TAILQ_FIRST(&in_ifaddrhead) == 0)
423		goto bad;
424	IP_STATINC(IP_STAT_TOTAL);
425	/*
426	 * If the IP header is not aligned, slurp it up into a new
427	 * mbuf with space for link headers, in the event we forward
428	 * it.  Otherwise, if it is aligned, make sure the entire
429	 * base IP header is in the first mbuf of the chain.
430	 */
431	if (IP_HDR_ALIGNED_P(mtod(m, void *)) == 0) {
432		if ((m = m_copyup(m, sizeof(struct ip),
433				  (max_linkhdr + 3) & ~3)) == NULL) {
434			/* XXXJRT new stat, please */
435			IP_STATINC(IP_STAT_TOOSMALL);
436			return;
437		}
438	} else if (__predict_false(m->m_len < sizeof (struct ip))) {
439		if ((m = m_pullup(m, sizeof (struct ip))) == NULL) {
440			IP_STATINC(IP_STAT_TOOSMALL);
441			return;
442		}
443	}
444	ip = mtod(m, struct ip *);
445	if (ip->ip_v != IPVERSION) {
446		IP_STATINC(IP_STAT_BADVERS);
447		goto bad;
448	}
449	hlen = ip->ip_hl << 2;
450	if (hlen < sizeof(struct ip)) {	/* minimum header length */
451		IP_STATINC(IP_STAT_BADHLEN);
452		goto bad;
453	}
454	if (hlen > m->m_len) {
455		if ((m = m_pullup(m, hlen)) == NULL) {
456			IP_STATINC(IP_STAT_BADHLEN);
457			return;
458		}
459		ip = mtod(m, struct ip *);
460	}
461
462	/*
463	 * RFC1122: packets with a multicast source address are
464	 * not allowed.
465	 */
466	if (IN_MULTICAST(ip->ip_src.s_addr)) {
467		IP_STATINC(IP_STAT_BADADDR);
468		goto bad;
469	}
470
471	/* 127/8 must not appear on wire - RFC1122 */
472	if ((ntohl(ip->ip_dst.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET ||
473	    (ntohl(ip->ip_src.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET) {
474		if ((m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) == 0) {
475			IP_STATINC(IP_STAT_BADADDR);
476			goto bad;
477		}
478	}
479
480	switch (m->m_pkthdr.csum_flags &
481		((m->m_pkthdr.rcvif->if_csum_flags_rx & M_CSUM_IPv4) |
482		 M_CSUM_IPv4_BAD)) {
483	case M_CSUM_IPv4|M_CSUM_IPv4_BAD:
484		INET_CSUM_COUNTER_INCR(&ip_hwcsum_bad);
485		goto badcsum;
486
487	case M_CSUM_IPv4:
488		/* Checksum was okay. */
489		INET_CSUM_COUNTER_INCR(&ip_hwcsum_ok);
490		break;
491
492	default:
493		/*
494		 * Must compute it ourselves.  Maybe skip checksum on
495		 * loopback interfaces.
496		 */
497		if (__predict_true(!(m->m_pkthdr.rcvif->if_flags &
498				     IFF_LOOPBACK) || ip_do_loopback_cksum)) {
499			INET_CSUM_COUNTER_INCR(&ip_swcsum);
500			if (in_cksum(m, hlen) != 0)
501				goto badcsum;
502		}
503		break;
504	}
505
506	/* Retrieve the packet length. */
507	len = ntohs(ip->ip_len);
508
509	/*
510	 * Check for additional length bogosity
511	 */
512	if (len < hlen) {
513		IP_STATINC(IP_STAT_BADLEN);
514		goto bad;
515	}
516
517	/*
518	 * Check that the amount of data in the buffers
519	 * is as at least much as the IP header would have us expect.
520	 * Trim mbufs if longer than we expect.
521	 * Drop packet if shorter than we expect.
522	 */
523	if (m->m_pkthdr.len < len) {
524		IP_STATINC(IP_STAT_TOOSHORT);
525		goto bad;
526	}
527	if (m->m_pkthdr.len > len) {
528		if (m->m_len == m->m_pkthdr.len) {
529			m->m_len = len;
530			m->m_pkthdr.len = len;
531		} else
532			m_adj(m, len - m->m_pkthdr.len);
533	}
534
535	/*
536	 * Assume that we can create a fast-forward IP flow entry
537	 * based on this packet.
538	 */
539	m->m_flags |= M_CANFASTFWD;
540
541#ifdef PFIL_HOOKS
542	/*
543	 * Run through list of hooks for input packets.  If there are any
544	 * filters which require that additional packets in the flow are
545	 * not fast-forwarded, they must clear the M_CANFASTFWD flag.
546	 * Note that filters must _never_ set this flag, as another filter
547	 * in the list may have previously cleared it.
548	 */
549	/*
550	 * let ipfilter look at packet on the wire,
551	 * not the decapsulated packet.
552	 */
553#if defined(FAST_IPSEC)
554	if (!ipsec_indone(m))
555#else
556	if (1)
557#endif
558	{
559		struct in_addr odst;
560
561		odst = ip->ip_dst;
562		if (pfil_run_hooks(&inet_pfil_hook, &m, m->m_pkthdr.rcvif,
563		    PFIL_IN) != 0)
564			return;
565		if (m == NULL)
566			return;
567		ip = mtod(m, struct ip *);
568		hlen = ip->ip_hl << 2;
569		/*
570		 * XXX The setting of "srcrt" here is to prevent ip_forward()
571		 * from generating ICMP redirects for packets that have
572		 * been redirected by a hook back out on to the same LAN that
573		 * they came from and is not an indication that the packet
574		 * is being inffluenced by source routing options.  This
575		 * allows things like
576		 * "rdr tlp0 0/0 port 80 -> 1.1.1.200 3128 tcp"
577		 * where tlp0 is both on the 1.1.1.0/24 network and is the
578		 * default route for hosts on 1.1.1.0/24.  Of course this
579		 * also requires a "map tlp0 ..." to complete the story.
580		 * One might argue whether or not this kind of network config.
581		 * should be supported in this manner...
582		 */
583		srcrt = (odst.s_addr != ip->ip_dst.s_addr);
584	}
585#endif /* PFIL_HOOKS */
586
587#ifdef ALTQ
588	/* XXX Temporary until ALTQ is changed to use a pfil hook */
589	if (altq_input != NULL && (*altq_input)(m, AF_INET) == 0) {
590		/* packet dropped by traffic conditioner */
591		return;
592	}
593#endif
594
595	/*
596	 * Process options and, if not destined for us,
597	 * ship it on.  ip_dooptions returns 1 when an
598	 * error was detected (causing an icmp message
599	 * to be sent and the original packet to be freed).
600	 */
601	ip_nhops = 0;		/* for source routed packets */
602	if (hlen > sizeof (struct ip) && ip_dooptions(m))
603		return;
604
605	/*
606	 * Enable a consistency check between the destination address
607	 * and the arrival interface for a unicast packet (the RFC 1122
608	 * strong ES model) if IP forwarding is disabled and the packet
609	 * is not locally generated.
610	 *
611	 * XXX - Checking also should be disabled if the destination
612	 * address is ipnat'ed to a different interface.
613	 *
614	 * XXX - Checking is incompatible with IP aliases added
615	 * to the loopback interface instead of the interface where
616	 * the packets are received.
617	 *
618	 * XXX - We need to add a per ifaddr flag for this so that
619	 * we get finer grain control.
620	 */
621	checkif = ip_checkinterface && (ipforwarding == 0) &&
622	    (m->m_pkthdr.rcvif != NULL) &&
623	    ((m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) == 0);
624
625	/*
626	 * Check our list of addresses, to see if the packet is for us.
627	 *
628	 * Traditional 4.4BSD did not consult IFF_UP at all.
629	 * The behavior here is to treat addresses on !IFF_UP interface
630	 * as not mine.
631	 */
632	downmatch = 0;
633	LIST_FOREACH(ia, &IN_IFADDR_HASH(ip->ip_dst.s_addr), ia_hash) {
634		if (in_hosteq(ia->ia_addr.sin_addr, ip->ip_dst)) {
635			if (checkif && ia->ia_ifp != m->m_pkthdr.rcvif)
636				continue;
637			if ((ia->ia_ifp->if_flags & IFF_UP) != 0)
638				break;
639			else
640				downmatch++;
641		}
642	}
643	if (ia != NULL)
644		goto ours;
645	if (m->m_pkthdr.rcvif && m->m_pkthdr.rcvif->if_flags & IFF_BROADCAST) {
646		IFADDR_FOREACH(ifa, m->m_pkthdr.rcvif) {
647			if (ifa->ifa_addr->sa_family != AF_INET)
648				continue;
649			ia = ifatoia(ifa);
650			if (in_hosteq(ip->ip_dst, ia->ia_broadaddr.sin_addr) ||
651			    in_hosteq(ip->ip_dst, ia->ia_netbroadcast) ||
652			    /*
653			     * Look for all-0's host part (old broadcast addr),
654			     * either for subnet or net.
655			     */
656			    ip->ip_dst.s_addr == ia->ia_subnet ||
657			    ip->ip_dst.s_addr == ia->ia_net)
658				goto ours;
659			/*
660			 * An interface with IP address zero accepts
661			 * all packets that arrive on that interface.
662			 */
663			if (in_nullhost(ia->ia_addr.sin_addr))
664				goto ours;
665		}
666	}
667	if (IN_MULTICAST(ip->ip_dst.s_addr)) {
668		struct in_multi *inm;
669#ifdef MROUTING
670		extern struct socket *ip_mrouter;
671
672		if (ip_mrouter) {
673			/*
674			 * If we are acting as a multicast router, all
675			 * incoming multicast packets are passed to the
676			 * kernel-level multicast forwarding function.
677			 * The packet is returned (relatively) intact; if
678			 * ip_mforward() returns a non-zero value, the packet
679			 * must be discarded, else it may be accepted below.
680			 *
681			 * (The IP ident field is put in the same byte order
682			 * as expected when ip_mforward() is called from
683			 * ip_output().)
684			 */
685			if (ip_mforward(m, m->m_pkthdr.rcvif) != 0) {
686				IP_STATINC(IP_STAT_CANTFORWARD);
687				m_freem(m);
688				return;
689			}
690
691			/*
692			 * The process-level routing demon needs to receive
693			 * all multicast IGMP packets, whether or not this
694			 * host belongs to their destination groups.
695			 */
696			if (ip->ip_p == IPPROTO_IGMP)
697				goto ours;
698			IP_STATINC(IP_STAT_CANTFORWARD);
699		}
700#endif
701		/*
702		 * See if we belong to the destination multicast group on the
703		 * arrival interface.
704		 */
705		IN_LOOKUP_MULTI(ip->ip_dst, m->m_pkthdr.rcvif, inm);
706		if (inm == NULL) {
707			IP_STATINC(IP_STAT_CANTFORWARD);
708			m_freem(m);
709			return;
710		}
711		goto ours;
712	}
713	if (ip->ip_dst.s_addr == INADDR_BROADCAST ||
714	    in_nullhost(ip->ip_dst))
715		goto ours;
716
717	/*
718	 * Not for us; forward if possible and desirable.
719	 */
720	if (ipforwarding == 0) {
721		IP_STATINC(IP_STAT_CANTFORWARD);
722		m_freem(m);
723	} else {
724		/*
725		 * If ip_dst matched any of my address on !IFF_UP interface,
726		 * and there's no IFF_UP interface that matches ip_dst,
727		 * send icmp unreach.  Forwarding it will result in in-kernel
728		 * forwarding loop till TTL goes to 0.
729		 */
730		if (downmatch) {
731			icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_HOST, 0, 0);
732			IP_STATINC(IP_STAT_CANTFORWARD);
733			return;
734		}
735#ifdef FAST_IPSEC
736		mtag = m_tag_find(m, PACKET_TAG_IPSEC_IN_DONE, NULL);
737		s = splsoftnet();
738		if (mtag != NULL) {
739			tdbi = (struct tdb_ident *)(mtag + 1);
740			sp = ipsec_getpolicy(tdbi, IPSEC_DIR_INBOUND);
741		} else {
742			sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND,
743						   IP_FORWARDING, &error);
744		}
745		if (sp == NULL) {	/* NB: can happen if error */
746			splx(s);
747			/*XXX error stat???*/
748			DPRINTF(("ip_input: no SP for forwarding\n"));	/*XXX*/
749			goto bad;
750		}
751
752		/*
753		 * Check security policy against packet attributes.
754		 */
755		error = ipsec_in_reject(sp, m);
756		KEY_FREESP(&sp);
757		splx(s);
758		if (error) {
759			IP_STATINC(IP_STAT_CANTFORWARD);
760			goto bad;
761		}
762
763		/*
764		 * Peek at the outbound SP for this packet to determine if
765		 * it's a Fast Forward candidate.
766		 */
767		mtag = m_tag_find(m, PACKET_TAG_IPSEC_PENDING_TDB, NULL);
768		if (mtag != NULL)
769			m->m_flags &= ~M_CANFASTFWD;
770		else {
771			s = splsoftnet();
772			sp = ipsec4_checkpolicy(m, IPSEC_DIR_OUTBOUND,
773			    (IP_FORWARDING |
774			     (ip_directedbcast ? IP_ALLOWBROADCAST : 0)),
775			    &error, NULL);
776			if (sp != NULL) {
777				m->m_flags &= ~M_CANFASTFWD;
778				KEY_FREESP(&sp);
779			}
780			splx(s);
781		}
782#endif	/* FAST_IPSEC */
783
784		ip_forward(m, srcrt);
785	}
786	return;
787
788ours:
789	/*
790	 * If offset or IP_MF are set, must reassemble.
791	 */
792	if (ip->ip_off & ~htons(IP_DF|IP_RF)) {
793		/*
794		 * Pass to IP reassembly mechanism.
795		 */
796		if (ip_reass_packet(&m, ip) != 0) {
797			/* Failed; invalid fragment(s) or packet. */
798			goto bad;
799		}
800		if (m == NULL) {
801			/* More fragments should come; silently return. */
802			return;
803		}
804		/*
805		 * Reassembly is done, we have the final packet.
806		 * Updated cached data in local variable(s).
807		 */
808		ip = mtod(m, struct ip *);
809		hlen = ip->ip_hl << 2;
810	}
811
812#ifdef FAST_IPSEC
813	/*
814	 * enforce IPsec policy checking if we are seeing last header.
815	 * note that we do not visit this with protocols with pcb layer
816	 * code - like udp/tcp/raw ip.
817	 */
818	if ((inetsw[ip_protox[ip->ip_p]].pr_flags & PR_LASTHDR) != 0) {
819		/*
820		 * Check if the packet has already had IPsec processing
821		 * done.  If so, then just pass it along.  This tag gets
822		 * set during AH, ESP, etc. input handling, before the
823		 * packet is returned to the ip input queue for delivery.
824		 */
825		mtag = m_tag_find(m, PACKET_TAG_IPSEC_IN_DONE, NULL);
826		s = splsoftnet();
827		if (mtag != NULL) {
828			tdbi = (struct tdb_ident *)(mtag + 1);
829			sp = ipsec_getpolicy(tdbi, IPSEC_DIR_INBOUND);
830		} else {
831			sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND,
832						   IP_FORWARDING, &error);
833		}
834		if (sp != NULL) {
835			/*
836			 * Check security policy against packet attributes.
837			 */
838			error = ipsec_in_reject(sp, m);
839			KEY_FREESP(&sp);
840		} else {
841			/* XXX error stat??? */
842			error = EINVAL;
843DPRINTF(("ip_input: no SP, packet discarded\n"));/*XXX*/
844		}
845		splx(s);
846		if (error)
847			goto bad;
848	}
849#endif /* FAST_IPSEC */
850
851	/*
852	 * Switch out to protocol's input routine.
853	 */
854#if IFA_STATS
855	if (ia && ip)
856		ia->ia_ifa.ifa_data.ifad_inbytes += ntohs(ip->ip_len);
857#endif
858	IP_STATINC(IP_STAT_DELIVERED);
859    {
860	int off = hlen, nh = ip->ip_p;
861
862	(*inetsw[ip_protox[nh]].pr_input)(m, off, nh);
863	return;
864    }
865bad:
866	m_freem(m);
867	return;
868
869badcsum:
870	IP_STATINC(IP_STAT_BADSUM);
871	m_freem(m);
872}
873
874/*
875 * IP timer processing.
876 */
877void
878ip_slowtimo(void)
879{
880
881	mutex_enter(softnet_lock);
882	KERNEL_LOCK(1, NULL);
883
884	ip_reass_slowtimo();
885
886	KERNEL_UNLOCK_ONE(NULL);
887	mutex_exit(softnet_lock);
888}
889
890/*
891 * IP drain processing.
892 */
893void
894ip_drain(void)
895{
896
897	KERNEL_LOCK(1, NULL);
898	ip_reass_drain();
899	KERNEL_UNLOCK_ONE(NULL);
900}
901
902/*
903 * Do option processing on a datagram,
904 * possibly discarding it if bad options are encountered,
905 * or forwarding it if source-routed.
906 * Returns 1 if packet has been forwarded/freed,
907 * 0 if the packet should be processed further.
908 */
909int
910ip_dooptions(struct mbuf *m)
911{
912	struct ip *ip = mtod(m, struct ip *);
913	u_char *cp, *cp0;
914	struct ip_timestamp *ipt;
915	struct in_ifaddr *ia;
916	int opt, optlen, cnt, off, code, type = ICMP_PARAMPROB, forward = 0;
917	struct in_addr dst;
918	n_time ntime;
919
920	dst = ip->ip_dst;
921	cp = (u_char *)(ip + 1);
922	cnt = (ip->ip_hl << 2) - sizeof (struct ip);
923	for (; cnt > 0; cnt -= optlen, cp += optlen) {
924		opt = cp[IPOPT_OPTVAL];
925		if (opt == IPOPT_EOL)
926			break;
927		if (opt == IPOPT_NOP)
928			optlen = 1;
929		else {
930			if (cnt < IPOPT_OLEN + sizeof(*cp)) {
931				code = &cp[IPOPT_OLEN] - (u_char *)ip;
932				goto bad;
933			}
934			optlen = cp[IPOPT_OLEN];
935			if (optlen < IPOPT_OLEN + sizeof(*cp) || optlen > cnt) {
936				code = &cp[IPOPT_OLEN] - (u_char *)ip;
937				goto bad;
938			}
939		}
940		switch (opt) {
941
942		default:
943			break;
944
945		/*
946		 * Source routing with record.
947		 * Find interface with current destination address.
948		 * If none on this machine then drop if strictly routed,
949		 * or do nothing if loosely routed.
950		 * Record interface address and bring up next address
951		 * component.  If strictly routed make sure next
952		 * address is on directly accessible net.
953		 */
954		case IPOPT_LSRR:
955		case IPOPT_SSRR:
956			if (ip_allowsrcrt == 0) {
957				type = ICMP_UNREACH;
958				code = ICMP_UNREACH_NET_PROHIB;
959				goto bad;
960			}
961			if (optlen < IPOPT_OFFSET + sizeof(*cp)) {
962				code = &cp[IPOPT_OLEN] - (u_char *)ip;
963				goto bad;
964			}
965			if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) {
966				code = &cp[IPOPT_OFFSET] - (u_char *)ip;
967				goto bad;
968			}
969			ipaddr.sin_addr = ip->ip_dst;
970			ia = ifatoia(ifa_ifwithaddr(sintosa(&ipaddr)));
971			if (ia == 0) {
972				if (opt == IPOPT_SSRR) {
973					type = ICMP_UNREACH;
974					code = ICMP_UNREACH_SRCFAIL;
975					goto bad;
976				}
977				/*
978				 * Loose routing, and not at next destination
979				 * yet; nothing to do except forward.
980				 */
981				break;
982			}
983			off--;			/* 0 origin */
984			if ((off + sizeof(struct in_addr)) > optlen) {
985				/*
986				 * End of source route.  Should be for us.
987				 */
988				save_rte(cp, ip->ip_src);
989				break;
990			}
991			/*
992			 * locate outgoing interface
993			 */
994			memcpy((void *)&ipaddr.sin_addr, (void *)(cp + off),
995			    sizeof(ipaddr.sin_addr));
996			if (opt == IPOPT_SSRR)
997				ia = ifatoia(ifa_ifwithladdr(sintosa(&ipaddr)));
998			else
999				ia = ip_rtaddr(ipaddr.sin_addr);
1000			if (ia == 0) {
1001				type = ICMP_UNREACH;
1002				code = ICMP_UNREACH_SRCFAIL;
1003				goto bad;
1004			}
1005			ip->ip_dst = ipaddr.sin_addr;
1006			bcopy((void *)&ia->ia_addr.sin_addr,
1007			    (void *)(cp + off), sizeof(struct in_addr));
1008			cp[IPOPT_OFFSET] += sizeof(struct in_addr);
1009			/*
1010			 * Let ip_intr's mcast routing check handle mcast pkts
1011			 */
1012			forward = !IN_MULTICAST(ip->ip_dst.s_addr);
1013			break;
1014
1015		case IPOPT_RR:
1016			if (optlen < IPOPT_OFFSET + sizeof(*cp)) {
1017				code = &cp[IPOPT_OLEN] - (u_char *)ip;
1018				goto bad;
1019			}
1020			if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) {
1021				code = &cp[IPOPT_OFFSET] - (u_char *)ip;
1022				goto bad;
1023			}
1024			/*
1025			 * If no space remains, ignore.
1026			 */
1027			off--;			/* 0 origin */
1028			if ((off + sizeof(struct in_addr)) > optlen)
1029				break;
1030			memcpy((void *)&ipaddr.sin_addr, (void *)(&ip->ip_dst),
1031			    sizeof(ipaddr.sin_addr));
1032			/*
1033			 * locate outgoing interface; if we're the destination,
1034			 * use the incoming interface (should be same).
1035			 */
1036			if ((ia = ifatoia(ifa_ifwithaddr(sintosa(&ipaddr))))
1037			    == NULL &&
1038			    (ia = ip_rtaddr(ipaddr.sin_addr)) == NULL) {
1039				type = ICMP_UNREACH;
1040				code = ICMP_UNREACH_HOST;
1041				goto bad;
1042			}
1043			bcopy((void *)&ia->ia_addr.sin_addr,
1044			    (void *)(cp + off), sizeof(struct in_addr));
1045			cp[IPOPT_OFFSET] += sizeof(struct in_addr);
1046			break;
1047
1048		case IPOPT_TS:
1049			code = cp - (u_char *)ip;
1050			ipt = (struct ip_timestamp *)cp;
1051			if (ipt->ipt_len < 4 || ipt->ipt_len > 40) {
1052				code = (u_char *)&ipt->ipt_len - (u_char *)ip;
1053				goto bad;
1054			}
1055			if (ipt->ipt_ptr < 5) {
1056				code = (u_char *)&ipt->ipt_ptr - (u_char *)ip;
1057				goto bad;
1058			}
1059			if (ipt->ipt_ptr > ipt->ipt_len - sizeof (int32_t)) {
1060				if (++ipt->ipt_oflw == 0) {
1061					code = (u_char *)&ipt->ipt_ptr -
1062					    (u_char *)ip;
1063					goto bad;
1064				}
1065				break;
1066			}
1067			cp0 = (cp + ipt->ipt_ptr - 1);
1068			switch (ipt->ipt_flg) {
1069
1070			case IPOPT_TS_TSONLY:
1071				break;
1072
1073			case IPOPT_TS_TSANDADDR:
1074				if (ipt->ipt_ptr - 1 + sizeof(n_time) +
1075				    sizeof(struct in_addr) > ipt->ipt_len) {
1076					code = (u_char *)&ipt->ipt_ptr -
1077					    (u_char *)ip;
1078					goto bad;
1079				}
1080				ipaddr.sin_addr = dst;
1081				ia = ifatoia(ifaof_ifpforaddr(sintosa(&ipaddr),
1082				    m->m_pkthdr.rcvif));
1083				if (ia == 0)
1084					continue;
1085				bcopy(&ia->ia_addr.sin_addr,
1086				    cp0, sizeof(struct in_addr));
1087				ipt->ipt_ptr += sizeof(struct in_addr);
1088				break;
1089
1090			case IPOPT_TS_PRESPEC:
1091				if (ipt->ipt_ptr - 1 + sizeof(n_time) +
1092				    sizeof(struct in_addr) > ipt->ipt_len) {
1093					code = (u_char *)&ipt->ipt_ptr -
1094					    (u_char *)ip;
1095					goto bad;
1096				}
1097				memcpy(&ipaddr.sin_addr, cp0,
1098				    sizeof(struct in_addr));
1099				if (ifatoia(ifa_ifwithaddr(sintosa(&ipaddr)))
1100				    == NULL)
1101					continue;
1102				ipt->ipt_ptr += sizeof(struct in_addr);
1103				break;
1104
1105			default:
1106				/* XXX can't take &ipt->ipt_flg */
1107				code = (u_char *)&ipt->ipt_ptr -
1108				    (u_char *)ip + 1;
1109				goto bad;
1110			}
1111			ntime = iptime();
1112			cp0 = (u_char *) &ntime; /* XXX grumble, GCC... */
1113			memmove((char *)cp + ipt->ipt_ptr - 1, cp0,
1114			    sizeof(n_time));
1115			ipt->ipt_ptr += sizeof(n_time);
1116		}
1117	}
1118	if (forward) {
1119		if (ip_forwsrcrt == 0) {
1120			type = ICMP_UNREACH;
1121			code = ICMP_UNREACH_SRCFAIL;
1122			goto bad;
1123		}
1124		ip_forward(m, 1);
1125		return (1);
1126	}
1127	return (0);
1128bad:
1129	icmp_error(m, type, code, 0, 0);
1130	IP_STATINC(IP_STAT_BADOPTIONS);
1131	return (1);
1132}
1133
1134/*
1135 * Given address of next destination (final or next hop),
1136 * return internet address info of interface to be used to get there.
1137 */
1138struct in_ifaddr *
1139ip_rtaddr(struct in_addr dst)
1140{
1141	struct rtentry *rt;
1142	union {
1143		struct sockaddr		dst;
1144		struct sockaddr_in	dst4;
1145	} u;
1146
1147	sockaddr_in_init(&u.dst4, &dst, 0);
1148
1149	if ((rt = rtcache_lookup(&ipforward_rt, &u.dst)) == NULL)
1150		return NULL;
1151
1152	return ifatoia(rt->rt_ifa);
1153}
1154
1155/*
1156 * Save incoming source route for use in replies,
1157 * to be picked up later by ip_srcroute if the receiver is interested.
1158 */
1159void
1160save_rte(u_char *option, struct in_addr dst)
1161{
1162	unsigned olen;
1163
1164	olen = option[IPOPT_OLEN];
1165#ifdef DIAGNOSTIC
1166	if (ipprintfs)
1167		printf("save_rte: olen %d\n", olen);
1168#endif /* 0 */
1169	if (olen > sizeof(ip_srcrt) - (1 + sizeof(dst)))
1170		return;
1171	memcpy((void *)ip_srcrt.srcopt, (void *)option, olen);
1172	ip_nhops = (olen - IPOPT_OFFSET - 1) / sizeof(struct in_addr);
1173	ip_srcrt.dst = dst;
1174}
1175
1176/*
1177 * Retrieve incoming source route for use in replies,
1178 * in the same form used by setsockopt.
1179 * The first hop is placed before the options, will be removed later.
1180 */
1181struct mbuf *
1182ip_srcroute(void)
1183{
1184	struct in_addr *p, *q;
1185	struct mbuf *m;
1186
1187	if (ip_nhops == 0)
1188		return NULL;
1189	m = m_get(M_DONTWAIT, MT_SOOPTS);
1190	if (m == 0)
1191		return NULL;
1192
1193	MCLAIM(m, &inetdomain.dom_mowner);
1194#define OPTSIZ	(sizeof(ip_srcrt.nop) + sizeof(ip_srcrt.srcopt))
1195
1196	/* length is (nhops+1)*sizeof(addr) + sizeof(nop + srcrt header) */
1197	m->m_len = ip_nhops * sizeof(struct in_addr) + sizeof(struct in_addr) +
1198	    OPTSIZ;
1199#ifdef DIAGNOSTIC
1200	if (ipprintfs)
1201		printf("ip_srcroute: nhops %d mlen %d", ip_nhops, m->m_len);
1202#endif
1203
1204	/*
1205	 * First save first hop for return route
1206	 */
1207	p = &ip_srcrt.route[ip_nhops - 1];
1208	*(mtod(m, struct in_addr *)) = *p--;
1209#ifdef DIAGNOSTIC
1210	if (ipprintfs)
1211		printf(" hops %x", ntohl(mtod(m, struct in_addr *)->s_addr));
1212#endif
1213
1214	/*
1215	 * Copy option fields and padding (nop) to mbuf.
1216	 */
1217	ip_srcrt.nop = IPOPT_NOP;
1218	ip_srcrt.srcopt[IPOPT_OFFSET] = IPOPT_MINOFF;
1219	memmove(mtod(m, char *) + sizeof(struct in_addr), &ip_srcrt.nop,
1220	    OPTSIZ);
1221	q = (struct in_addr *)(mtod(m, char *) +
1222	    sizeof(struct in_addr) + OPTSIZ);
1223#undef OPTSIZ
1224	/*
1225	 * Record return path as an IP source route,
1226	 * reversing the path (pointers are now aligned).
1227	 */
1228	while (p >= ip_srcrt.route) {
1229#ifdef DIAGNOSTIC
1230		if (ipprintfs)
1231			printf(" %x", ntohl(q->s_addr));
1232#endif
1233		*q++ = *p--;
1234	}
1235	/*
1236	 * Last hop goes to final destination.
1237	 */
1238	*q = ip_srcrt.dst;
1239#ifdef DIAGNOSTIC
1240	if (ipprintfs)
1241		printf(" %x\n", ntohl(q->s_addr));
1242#endif
1243	return (m);
1244}
1245
1246const int inetctlerrmap[PRC_NCMDS] = {
1247	[PRC_MSGSIZE] = EMSGSIZE,
1248	[PRC_HOSTDEAD] = EHOSTDOWN,
1249	[PRC_HOSTUNREACH] = EHOSTUNREACH,
1250	[PRC_UNREACH_NET] = EHOSTUNREACH,
1251	[PRC_UNREACH_HOST] = EHOSTUNREACH,
1252	[PRC_UNREACH_PROTOCOL] = ECONNREFUSED,
1253	[PRC_UNREACH_PORT] = ECONNREFUSED,
1254	[PRC_UNREACH_SRCFAIL] = EHOSTUNREACH,
1255	[PRC_PARAMPROB] = ENOPROTOOPT,
1256};
1257
1258void
1259ip_fasttimo(void)
1260{
1261	if (ip_drainwanted) {
1262		ip_drain();
1263		ip_drainwanted = 0;
1264	}
1265}
1266
1267void
1268ip_drainstub(void)
1269{
1270	ip_drainwanted = 1;
1271}
1272
1273/*
1274 * Forward a packet.  If some error occurs return the sender
1275 * an icmp packet.  Note we can't always generate a meaningful
1276 * icmp message because icmp doesn't have a large enough repertoire
1277 * of codes and types.
1278 *
1279 * If not forwarding, just drop the packet.  This could be confusing
1280 * if ipforwarding was zero but some routing protocol was advancing
1281 * us as a gateway to somewhere.  However, we must let the routing
1282 * protocol deal with that.
1283 *
1284 * The srcrt parameter indicates whether the packet is being forwarded
1285 * via a source route.
1286 */
1287void
1288ip_forward(struct mbuf *m, int srcrt)
1289{
1290	struct ip *ip = mtod(m, struct ip *);
1291	struct rtentry *rt;
1292	int error, type = 0, code = 0, destmtu = 0;
1293	struct mbuf *mcopy;
1294	n_long dest;
1295	union {
1296		struct sockaddr		dst;
1297		struct sockaddr_in	dst4;
1298	} u;
1299
1300	/*
1301	 * We are now in the output path.
1302	 */
1303	MCLAIM(m, &ip_tx_mowner);
1304
1305	/*
1306	 * Clear any in-bound checksum flags for this packet.
1307	 */
1308	m->m_pkthdr.csum_flags = 0;
1309
1310	dest = 0;
1311#ifdef DIAGNOSTIC
1312	if (ipprintfs) {
1313		printf("forward: src %s ", inet_ntoa(ip->ip_src));
1314		printf("dst %s ttl %x\n", inet_ntoa(ip->ip_dst), ip->ip_ttl);
1315	}
1316#endif
1317	if (m->m_flags & (M_BCAST|M_MCAST) || in_canforward(ip->ip_dst) == 0) {
1318		IP_STATINC(IP_STAT_CANTFORWARD);
1319		m_freem(m);
1320		return;
1321	}
1322	if (ip->ip_ttl <= IPTTLDEC) {
1323		icmp_error(m, ICMP_TIMXCEED, ICMP_TIMXCEED_INTRANS, dest, 0);
1324		return;
1325	}
1326
1327	sockaddr_in_init(&u.dst4, &ip->ip_dst, 0);
1328	if ((rt = rtcache_lookup(&ipforward_rt, &u.dst)) == NULL) {
1329		icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_NET, dest, 0);
1330		return;
1331	}
1332
1333	/*
1334	 * Save at most 68 bytes of the packet in case
1335	 * we need to generate an ICMP message to the src.
1336	 * Pullup to avoid sharing mbuf cluster between m and mcopy.
1337	 */
1338	mcopy = m_copym(m, 0, imin(ntohs(ip->ip_len), 68), M_DONTWAIT);
1339	if (mcopy)
1340		mcopy = m_pullup(mcopy, ip->ip_hl << 2);
1341
1342	ip->ip_ttl -= IPTTLDEC;
1343
1344	/*
1345	 * If forwarding packet using same interface that it came in on,
1346	 * perhaps should send a redirect to sender to shortcut a hop.
1347	 * Only send redirect if source is sending directly to us,
1348	 * and if packet was not source routed (or has any options).
1349	 * Also, don't send redirect if forwarding using a default route
1350	 * or a route modified by a redirect.
1351	 */
1352	if (rt->rt_ifp == m->m_pkthdr.rcvif &&
1353	    (rt->rt_flags & (RTF_DYNAMIC|RTF_MODIFIED)) == 0 &&
1354	    !in_nullhost(satocsin(rt_getkey(rt))->sin_addr) &&
1355	    ipsendredirects && !srcrt) {
1356		if (rt->rt_ifa &&
1357		    (ip->ip_src.s_addr & ifatoia(rt->rt_ifa)->ia_subnetmask) ==
1358		    ifatoia(rt->rt_ifa)->ia_subnet) {
1359			if (rt->rt_flags & RTF_GATEWAY)
1360				dest = satosin(rt->rt_gateway)->sin_addr.s_addr;
1361			else
1362				dest = ip->ip_dst.s_addr;
1363			/*
1364			 * Router requirements says to only send host
1365			 * redirects.
1366			 */
1367			type = ICMP_REDIRECT;
1368			code = ICMP_REDIRECT_HOST;
1369#ifdef DIAGNOSTIC
1370			if (ipprintfs)
1371				printf("redirect (%d) to %x\n", code,
1372				    (u_int32_t)dest);
1373#endif
1374		}
1375	}
1376
1377	error = ip_output(m, NULL, &ipforward_rt,
1378	    (IP_FORWARDING | (ip_directedbcast ? IP_ALLOWBROADCAST : 0)),
1379	    NULL, NULL);
1380
1381	if (error)
1382		IP_STATINC(IP_STAT_CANTFORWARD);
1383	else {
1384		uint64_t *ips = IP_STAT_GETREF();
1385		ips[IP_STAT_FORWARD]++;
1386		if (type) {
1387			ips[IP_STAT_REDIRECTSENT]++;
1388			IP_STAT_PUTREF();
1389		} else {
1390			IP_STAT_PUTREF();
1391			if (mcopy) {
1392#ifdef GATEWAY
1393				if (mcopy->m_flags & M_CANFASTFWD)
1394					ipflow_create(&ipforward_rt, mcopy);
1395#endif
1396				m_freem(mcopy);
1397			}
1398			return;
1399		}
1400	}
1401	if (mcopy == NULL)
1402		return;
1403
1404	switch (error) {
1405
1406	case 0:				/* forwarded, but need redirect */
1407		/* type, code set above */
1408		break;
1409
1410	case ENETUNREACH:		/* shouldn't happen, checked above */
1411	case EHOSTUNREACH:
1412	case ENETDOWN:
1413	case EHOSTDOWN:
1414	default:
1415		type = ICMP_UNREACH;
1416		code = ICMP_UNREACH_HOST;
1417		break;
1418
1419	case EMSGSIZE:
1420		type = ICMP_UNREACH;
1421		code = ICMP_UNREACH_NEEDFRAG;
1422
1423		if ((rt = rtcache_validate(&ipforward_rt)) != NULL)
1424			destmtu = rt->rt_ifp->if_mtu;
1425
1426#if defined(FAST_IPSEC)
1427		{
1428			/*
1429			 * If the packet is routed over IPsec tunnel, tell the
1430			 * originator the tunnel MTU.
1431			 *	tunnel MTU = if MTU - sizeof(IP) - ESP/AH hdrsiz
1432			 * XXX quickhack!!!
1433			 */
1434
1435			struct secpolicy *sp;
1436			int ipsecerror;
1437			size_t ipsechdr;
1438			struct route *ro;
1439
1440			sp = ipsec4_getpolicybyaddr(mcopy,
1441			    IPSEC_DIR_OUTBOUND, IP_FORWARDING,
1442			    &ipsecerror);
1443
1444			if (sp != NULL) {
1445				/* count IPsec header size */
1446				ipsechdr = ipsec4_hdrsiz(mcopy,
1447				    IPSEC_DIR_OUTBOUND, NULL);
1448
1449				/*
1450				 * find the correct route for outer IPv4
1451				 * header, compute tunnel MTU.
1452				 */
1453
1454				if (sp->req != NULL
1455				 && sp->req->sav != NULL
1456				 && sp->req->sav->sah != NULL) {
1457					ro = &sp->req->sav->sah->sa_route;
1458					rt = rtcache_validate(ro);
1459					if (rt && rt->rt_ifp) {
1460						destmtu =
1461						    rt->rt_rmx.rmx_mtu ?
1462						    rt->rt_rmx.rmx_mtu :
1463						    rt->rt_ifp->if_mtu;
1464						destmtu -= ipsechdr;
1465					}
1466				}
1467
1468				KEY_FREESP(&sp);
1469			}
1470		}
1471#endif /*defined(FAST_IPSEC)*/
1472		IP_STATINC(IP_STAT_CANTFRAG);
1473		break;
1474
1475	case ENOBUFS:
1476#if 1
1477		/*
1478		 * a router should not generate ICMP_SOURCEQUENCH as
1479		 * required in RFC1812 Requirements for IP Version 4 Routers.
1480		 * source quench could be a big problem under DoS attacks,
1481		 * or if the underlying interface is rate-limited.
1482		 */
1483		if (mcopy)
1484			m_freem(mcopy);
1485		return;
1486#else
1487		type = ICMP_SOURCEQUENCH;
1488		code = 0;
1489		break;
1490#endif
1491	}
1492	icmp_error(mcopy, type, code, dest, destmtu);
1493}
1494
1495void
1496ip_savecontrol(struct inpcb *inp, struct mbuf **mp, struct ip *ip,
1497    struct mbuf *m)
1498{
1499
1500	if (inp->inp_socket->so_options & SO_TIMESTAMP
1501#ifdef SO_OTIMESTAMP
1502	    || inp->inp_socket->so_options & SO_OTIMESTAMP
1503#endif
1504	    ) {
1505		struct timeval tv;
1506
1507		microtime(&tv);
1508#ifdef SO_OTIMESTAMP
1509		if (inp->inp_socket->so_options & SO_OTIMESTAMP) {
1510			struct timeval50 tv50;
1511			timeval_to_timeval50(&tv, &tv50);
1512			*mp = sbcreatecontrol((void *) &tv50, sizeof(tv50),
1513			    SCM_OTIMESTAMP, SOL_SOCKET);
1514		} else
1515#endif
1516		*mp = sbcreatecontrol((void *) &tv, sizeof(tv),
1517		    SCM_TIMESTAMP, SOL_SOCKET);
1518		if (*mp)
1519			mp = &(*mp)->m_next;
1520	}
1521	if (inp->inp_flags & INP_RECVDSTADDR) {
1522		*mp = sbcreatecontrol((void *) &ip->ip_dst,
1523		    sizeof(struct in_addr), IP_RECVDSTADDR, IPPROTO_IP);
1524		if (*mp)
1525			mp = &(*mp)->m_next;
1526	}
1527#ifdef notyet
1528	/*
1529	 * XXX
1530	 * Moving these out of udp_input() made them even more broken
1531	 * than they already were.
1532	 *	- fenner@parc.xerox.com
1533	 */
1534	/* options were tossed already */
1535	if (inp->inp_flags & INP_RECVOPTS) {
1536		*mp = sbcreatecontrol((void *) opts_deleted_above,
1537		    sizeof(struct in_addr), IP_RECVOPTS, IPPROTO_IP);
1538		if (*mp)
1539			mp = &(*mp)->m_next;
1540	}
1541	/* ip_srcroute doesn't do what we want here, need to fix */
1542	if (inp->inp_flags & INP_RECVRETOPTS) {
1543		*mp = sbcreatecontrol((void *) ip_srcroute(),
1544		    sizeof(struct in_addr), IP_RECVRETOPTS, IPPROTO_IP);
1545		if (*mp)
1546			mp = &(*mp)->m_next;
1547	}
1548#endif
1549	if (inp->inp_flags & INP_RECVIF) {
1550		struct sockaddr_dl sdl;
1551
1552		sockaddr_dl_init(&sdl, sizeof(sdl),
1553		    (m->m_pkthdr.rcvif != NULL)
1554		        ?  m->m_pkthdr.rcvif->if_index
1555			: 0,
1556			0, NULL, 0, NULL, 0);
1557		*mp = sbcreatecontrol(&sdl, sdl.sdl_len, IP_RECVIF, IPPROTO_IP);
1558		if (*mp)
1559			mp = &(*mp)->m_next;
1560	}
1561	if (inp->inp_flags & INP_RECVTTL) {
1562		*mp = sbcreatecontrol((void *) &ip->ip_ttl,
1563		    sizeof(uint8_t), IP_RECVTTL, IPPROTO_IP);
1564		if (*mp)
1565			mp = &(*mp)->m_next;
1566	}
1567}
1568
1569/*
1570 * sysctl helper routine for net.inet.ip.forwsrcrt.
1571 */
1572static int
1573sysctl_net_inet_ip_forwsrcrt(SYSCTLFN_ARGS)
1574{
1575	int error, tmp;
1576	struct sysctlnode node;
1577
1578	node = *rnode;
1579	tmp = ip_forwsrcrt;
1580	node.sysctl_data = &tmp;
1581	error = sysctl_lookup(SYSCTLFN_CALL(&node));
1582	if (error || newp == NULL)
1583		return (error);
1584
1585	error = kauth_authorize_network(l->l_cred, KAUTH_NETWORK_FORWSRCRT,
1586	    0, NULL, NULL, NULL);
1587	if (error)
1588		return (error);
1589
1590	ip_forwsrcrt = tmp;
1591
1592	return (0);
1593}
1594
1595/*
1596 * sysctl helper routine for net.inet.ip.mtudisctimeout.  checks the
1597 * range of the new value and tweaks timers if it changes.
1598 */
1599static int
1600sysctl_net_inet_ip_pmtudto(SYSCTLFN_ARGS)
1601{
1602	int error, tmp;
1603	struct sysctlnode node;
1604
1605	node = *rnode;
1606	tmp = ip_mtudisc_timeout;
1607	node.sysctl_data = &tmp;
1608	error = sysctl_lookup(SYSCTLFN_CALL(&node));
1609	if (error || newp == NULL)
1610		return (error);
1611	if (tmp < 0)
1612		return (EINVAL);
1613
1614	mutex_enter(softnet_lock);
1615
1616	ip_mtudisc_timeout = tmp;
1617	rt_timer_queue_change(ip_mtudisc_timeout_q, ip_mtudisc_timeout);
1618
1619	mutex_exit(softnet_lock);
1620
1621	return (0);
1622}
1623
1624#ifdef GATEWAY
1625/*
1626 * sysctl helper routine for net.inet.ip.maxflows.
1627 */
1628static int
1629sysctl_net_inet_ip_maxflows(SYSCTLFN_ARGS)
1630{
1631	int error;
1632
1633	error = sysctl_lookup(SYSCTLFN_CALL(rnode));
1634	if (error || newp == NULL)
1635		return (error);
1636
1637	mutex_enter(softnet_lock);
1638	KERNEL_LOCK(1, NULL);
1639
1640	ipflow_prune();
1641
1642	KERNEL_UNLOCK_ONE(NULL);
1643	mutex_exit(softnet_lock);
1644
1645	return (0);
1646}
1647
1648static int
1649sysctl_net_inet_ip_hashsize(SYSCTLFN_ARGS)
1650{
1651	int error, tmp;
1652	struct sysctlnode node;
1653
1654	node = *rnode;
1655	tmp = ip_hashsize;
1656	node.sysctl_data = &tmp;
1657	error = sysctl_lookup(SYSCTLFN_CALL(&node));
1658	if (error || newp == NULL)
1659		return (error);
1660
1661	if ((tmp & (tmp - 1)) == 0 && tmp != 0) {
1662		/*
1663		 * Can only fail due to malloc()
1664		 */
1665		mutex_enter(softnet_lock);
1666		KERNEL_LOCK(1, NULL);
1667
1668		error = ipflow_invalidate_all(tmp);
1669
1670		KERNEL_UNLOCK_ONE(NULL);
1671		mutex_exit(softnet_lock);
1672
1673	} else {
1674		/*
1675		 * EINVAL if not a power of 2
1676	         */
1677		error = EINVAL;
1678	}
1679
1680	return error;
1681}
1682#endif /* GATEWAY */
1683
1684static int
1685sysctl_net_inet_ip_stats(SYSCTLFN_ARGS)
1686{
1687
1688	return (NETSTAT_SYSCTL(ipstat_percpu, IP_NSTATS));
1689}
1690
1691static void
1692sysctl_net_inet_ip_setup(struct sysctllog **clog)
1693{
1694	extern int subnetsarelocal, hostzeroisbroadcast;
1695
1696	sysctl_createv(clog, 0, NULL, NULL,
1697		       CTLFLAG_PERMANENT,
1698		       CTLTYPE_NODE, "net", NULL,
1699		       NULL, 0, NULL, 0,
1700		       CTL_NET, CTL_EOL);
1701	sysctl_createv(clog, 0, NULL, NULL,
1702		       CTLFLAG_PERMANENT,
1703		       CTLTYPE_NODE, "inet",
1704		       SYSCTL_DESCR("PF_INET related settings"),
1705		       NULL, 0, NULL, 0,
1706		       CTL_NET, PF_INET, CTL_EOL);
1707	sysctl_createv(clog, 0, NULL, NULL,
1708		       CTLFLAG_PERMANENT,
1709		       CTLTYPE_NODE, "ip",
1710		       SYSCTL_DESCR("IPv4 related settings"),
1711		       NULL, 0, NULL, 0,
1712		       CTL_NET, PF_INET, IPPROTO_IP, CTL_EOL);
1713
1714	sysctl_createv(clog, 0, NULL, NULL,
1715		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1716		       CTLTYPE_INT, "forwarding",
1717		       SYSCTL_DESCR("Enable forwarding of INET datagrams"),
1718		       NULL, 0, &ipforwarding, 0,
1719		       CTL_NET, PF_INET, IPPROTO_IP,
1720		       IPCTL_FORWARDING, CTL_EOL);
1721	sysctl_createv(clog, 0, NULL, NULL,
1722		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1723		       CTLTYPE_INT, "redirect",
1724		       SYSCTL_DESCR("Enable sending of ICMP redirect messages"),
1725		       NULL, 0, &ipsendredirects, 0,
1726		       CTL_NET, PF_INET, IPPROTO_IP,
1727		       IPCTL_SENDREDIRECTS, CTL_EOL);
1728	sysctl_createv(clog, 0, NULL, NULL,
1729		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1730		       CTLTYPE_INT, "ttl",
1731		       SYSCTL_DESCR("Default TTL for an INET datagram"),
1732		       NULL, 0, &ip_defttl, 0,
1733		       CTL_NET, PF_INET, IPPROTO_IP,
1734		       IPCTL_DEFTTL, CTL_EOL);
1735#ifdef IPCTL_DEFMTU
1736	sysctl_createv(clog, 0, NULL, NULL,
1737		       CTLFLAG_PERMANENT /* |CTLFLAG_READWRITE? */,
1738		       CTLTYPE_INT, "mtu",
1739		       SYSCTL_DESCR("Default MTA for an INET route"),
1740		       NULL, 0, &ip_mtu, 0,
1741		       CTL_NET, PF_INET, IPPROTO_IP,
1742		       IPCTL_DEFMTU, CTL_EOL);
1743#endif /* IPCTL_DEFMTU */
1744	sysctl_createv(clog, 0, NULL, NULL,
1745		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1746		       CTLTYPE_INT, "forwsrcrt",
1747		       SYSCTL_DESCR("Enable forwarding of source-routed "
1748				    "datagrams"),
1749		       sysctl_net_inet_ip_forwsrcrt, 0, &ip_forwsrcrt, 0,
1750		       CTL_NET, PF_INET, IPPROTO_IP,
1751		       IPCTL_FORWSRCRT, CTL_EOL);
1752	sysctl_createv(clog, 0, NULL, NULL,
1753		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1754		       CTLTYPE_INT, "directed-broadcast",
1755		       SYSCTL_DESCR("Enable forwarding of broadcast datagrams"),
1756		       NULL, 0, &ip_directedbcast, 0,
1757		       CTL_NET, PF_INET, IPPROTO_IP,
1758		       IPCTL_DIRECTEDBCAST, CTL_EOL);
1759	sysctl_createv(clog, 0, NULL, NULL,
1760		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1761		       CTLTYPE_INT, "allowsrcrt",
1762		       SYSCTL_DESCR("Accept source-routed datagrams"),
1763		       NULL, 0, &ip_allowsrcrt, 0,
1764		       CTL_NET, PF_INET, IPPROTO_IP,
1765		       IPCTL_ALLOWSRCRT, CTL_EOL);
1766	sysctl_createv(clog, 0, NULL, NULL,
1767		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1768		       CTLTYPE_INT, "subnetsarelocal",
1769		       SYSCTL_DESCR("Whether logical subnets are considered "
1770				    "local"),
1771		       NULL, 0, &subnetsarelocal, 0,
1772		       CTL_NET, PF_INET, IPPROTO_IP,
1773		       IPCTL_SUBNETSARELOCAL, CTL_EOL);
1774	sysctl_createv(clog, 0, NULL, NULL,
1775		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1776		       CTLTYPE_INT, "mtudisc",
1777		       SYSCTL_DESCR("Use RFC1191 Path MTU Discovery"),
1778		       NULL, 0, &ip_mtudisc, 0,
1779		       CTL_NET, PF_INET, IPPROTO_IP,
1780		       IPCTL_MTUDISC, CTL_EOL);
1781	sysctl_createv(clog, 0, NULL, NULL,
1782		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1783		       CTLTYPE_INT, "anonportmin",
1784		       SYSCTL_DESCR("Lowest ephemeral port number to assign"),
1785		       sysctl_net_inet_ip_ports, 0, &anonportmin, 0,
1786		       CTL_NET, PF_INET, IPPROTO_IP,
1787		       IPCTL_ANONPORTMIN, CTL_EOL);
1788	sysctl_createv(clog, 0, NULL, NULL,
1789		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1790		       CTLTYPE_INT, "anonportmax",
1791		       SYSCTL_DESCR("Highest ephemeral port number to assign"),
1792		       sysctl_net_inet_ip_ports, 0, &anonportmax, 0,
1793		       CTL_NET, PF_INET, IPPROTO_IP,
1794		       IPCTL_ANONPORTMAX, CTL_EOL);
1795	sysctl_createv(clog, 0, NULL, NULL,
1796		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1797		       CTLTYPE_INT, "mtudisctimeout",
1798		       SYSCTL_DESCR("Lifetime of a Path MTU Discovered route"),
1799		       sysctl_net_inet_ip_pmtudto, 0, (void *)&ip_mtudisc_timeout, 0,
1800		       CTL_NET, PF_INET, IPPROTO_IP,
1801		       IPCTL_MTUDISCTIMEOUT, CTL_EOL);
1802#ifdef GATEWAY
1803	sysctl_createv(clog, 0, NULL, NULL,
1804		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1805		       CTLTYPE_INT, "maxflows",
1806		       SYSCTL_DESCR("Number of flows for fast forwarding"),
1807		       sysctl_net_inet_ip_maxflows, 0, &ip_maxflows, 0,
1808		       CTL_NET, PF_INET, IPPROTO_IP,
1809		       IPCTL_MAXFLOWS, CTL_EOL);
1810	sysctl_createv(clog, 0, NULL, NULL,
1811			CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1812			CTLTYPE_INT, "hashsize",
1813			SYSCTL_DESCR("Size of hash table for fast forwarding (IPv4)"),
1814			sysctl_net_inet_ip_hashsize, 0, &ip_hashsize, 0,
1815			CTL_NET, PF_INET, IPPROTO_IP,
1816			CTL_CREATE, CTL_EOL);
1817#endif /* GATEWAY */
1818	sysctl_createv(clog, 0, NULL, NULL,
1819		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1820		       CTLTYPE_INT, "hostzerobroadcast",
1821		       SYSCTL_DESCR("All zeroes address is broadcast address"),
1822		       NULL, 0, &hostzeroisbroadcast, 0,
1823		       CTL_NET, PF_INET, IPPROTO_IP,
1824		       IPCTL_HOSTZEROBROADCAST, CTL_EOL);
1825#if NGIF > 0
1826	sysctl_createv(clog, 0, NULL, NULL,
1827		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1828		       CTLTYPE_INT, "gifttl",
1829		       SYSCTL_DESCR("Default TTL for a gif tunnel datagram"),
1830		       NULL, 0, &ip_gif_ttl, 0,
1831		       CTL_NET, PF_INET, IPPROTO_IP,
1832		       IPCTL_GIF_TTL, CTL_EOL);
1833#endif /* NGIF */
1834#ifndef IPNOPRIVPORTS
1835	sysctl_createv(clog, 0, NULL, NULL,
1836		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1837		       CTLTYPE_INT, "lowportmin",
1838		       SYSCTL_DESCR("Lowest privileged ephemeral port number "
1839				    "to assign"),
1840		       sysctl_net_inet_ip_ports, 0, &lowportmin, 0,
1841		       CTL_NET, PF_INET, IPPROTO_IP,
1842		       IPCTL_LOWPORTMIN, CTL_EOL);
1843	sysctl_createv(clog, 0, NULL, NULL,
1844		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1845		       CTLTYPE_INT, "lowportmax",
1846		       SYSCTL_DESCR("Highest privileged ephemeral port number "
1847				    "to assign"),
1848		       sysctl_net_inet_ip_ports, 0, &lowportmax, 0,
1849		       CTL_NET, PF_INET, IPPROTO_IP,
1850		       IPCTL_LOWPORTMAX, CTL_EOL);
1851#endif /* IPNOPRIVPORTS */
1852#if NGRE > 0
1853	sysctl_createv(clog, 0, NULL, NULL,
1854		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1855		       CTLTYPE_INT, "grettl",
1856		       SYSCTL_DESCR("Default TTL for a gre tunnel datagram"),
1857		       NULL, 0, &ip_gre_ttl, 0,
1858		       CTL_NET, PF_INET, IPPROTO_IP,
1859		       IPCTL_GRE_TTL, CTL_EOL);
1860#endif /* NGRE */
1861	sysctl_createv(clog, 0, NULL, NULL,
1862		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1863		       CTLTYPE_INT, "checkinterface",
1864		       SYSCTL_DESCR("Enable receive side of Strong ES model "
1865				    "from RFC1122"),
1866		       NULL, 0, &ip_checkinterface, 0,
1867		       CTL_NET, PF_INET, IPPROTO_IP,
1868		       IPCTL_CHECKINTERFACE, CTL_EOL);
1869	sysctl_createv(clog, 0, NULL, NULL,
1870		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1871		       CTLTYPE_INT, "random_id",
1872		       SYSCTL_DESCR("Assign random ip_id values"),
1873		       NULL, 0, &ip_do_randomid, 0,
1874		       CTL_NET, PF_INET, IPPROTO_IP,
1875		       IPCTL_RANDOMID, CTL_EOL);
1876	sysctl_createv(clog, 0, NULL, NULL,
1877		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1878		       CTLTYPE_INT, "do_loopback_cksum",
1879		       SYSCTL_DESCR("Perform IP checksum on loopback"),
1880		       NULL, 0, &ip_do_loopback_cksum, 0,
1881		       CTL_NET, PF_INET, IPPROTO_IP,
1882		       IPCTL_LOOPBACKCKSUM, CTL_EOL);
1883	sysctl_createv(clog, 0, NULL, NULL,
1884		       CTLFLAG_PERMANENT,
1885		       CTLTYPE_STRUCT, "stats",
1886		       SYSCTL_DESCR("IP statistics"),
1887		       sysctl_net_inet_ip_stats, 0, NULL, 0,
1888		       CTL_NET, PF_INET, IPPROTO_IP, IPCTL_STATS,
1889		       CTL_EOL);
1890
1891	/* anonportalgo RFC6056 subtree */
1892	const struct sysctlnode *rfc6056_node;
1893	sysctl_createv(clog, 0, NULL, &rfc6056_node,
1894		       CTLFLAG_PERMANENT,
1895		       CTLTYPE_NODE, "anonportalgo",
1896		       SYSCTL_DESCR("Anonymous Port Algorithm Selection (RFC 6056)"),
1897	    	       NULL, 0, NULL, 0,
1898		       CTL_NET, PF_INET, IPPROTO_IP, CTL_CREATE, CTL_EOL);
1899	sysctl_createv(clog, 0, &rfc6056_node, NULL,
1900		       CTLFLAG_PERMANENT,
1901		       CTLTYPE_STRING, "available",
1902		       SYSCTL_DESCR("available algorithms"),
1903		       sysctl_rfc6056_available, 0, NULL, RFC6056_MAXLEN,
1904		       CTL_CREATE, CTL_EOL);
1905	sysctl_createv(clog, 0, &rfc6056_node, NULL,
1906		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1907		       CTLTYPE_STRING, "selected",
1908		       SYSCTL_DESCR("selected algorithm"),
1909		       sysctl_rfc6056_selected, 0, NULL, RFC6056_MAXLEN,
1910		       CTL_CREATE, CTL_EOL);
1911}
1912
1913void
1914ip_statinc(u_int stat)
1915{
1916
1917	KASSERT(stat < IP_NSTATS);
1918	IP_STATINC(stat);
1919}
1920