1 /* $NetBSD: ip_input.c,v 1.402 2022/09/02 03:50:00 thorpej 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 1.402 2022/09/02 03:50:00 thorpej Exp $");
95
96 #ifdef _KERNEL_OPT
97 #include "opt_inet.h"
98 #include "opt_gateway.h"
99 #include "opt_ipsec.h"
100 #include "opt_mrouting.h"
101 #include "opt_mbuftrace.h"
102 #include "opt_inet_csum.h"
103 #include "opt_net_mpsafe.h"
104 #endif
105
106 #include "arp.h"
107
108 #include <sys/param.h>
109 #include <sys/systm.h>
110 #include <sys/cpu.h>
111 #include <sys/mbuf.h>
112 #include <sys/domain.h>
113 #include <sys/protosw.h>
114 #include <sys/socket.h>
115 #include <sys/socketvar.h>
116 #include <sys/errno.h>
117 #include <sys/time.h>
118 #include <sys/kernel.h>
119 #include <sys/pool.h>
120 #include <sys/sysctl.h>
121 #include <sys/kauth.h>
122
123 #include <net/if.h>
124 #include <net/if_dl.h>
125 #include <net/route.h>
126 #include <net/pktqueue.h>
127 #include <net/pfil.h>
128
129 #include <netinet/in.h>
130 #include <netinet/in_systm.h>
131 #include <netinet/ip.h>
132 #include <netinet/in_pcb.h>
133 #include <netinet/in_proto.h>
134 #include <netinet/in_var.h>
135 #include <netinet/ip_var.h>
136 #include <netinet/ip_private.h>
137 #include <netinet/ip_icmp.h>
138 /* just for gif_ttl */
139 #include <netinet/in_gif.h>
140 #include "gif.h"
141 #include <net/if_gre.h>
142 #include "gre.h"
143
144 #ifdef MROUTING
145 #include <netinet/ip_mroute.h>
146 #endif
147 #include <netinet/portalgo.h>
148
149 #ifdef IPSEC
150 #include <netipsec/ipsec.h>
151 #endif
152
153 #ifndef IPFORWARDING
154 #ifdef GATEWAY
155 #define IPFORWARDING 1 /* forward IP packets not for us */
156 #else
157 #define IPFORWARDING 0 /* don't forward IP packets not for us */
158 #endif
159 #endif
160
161 #define IPMTUDISCTIMEOUT (10 * 60) /* as per RFC 1191 */
162
163 int ipforwarding = IPFORWARDING;
164 int ipsendredirects = 1;
165 int ip_defttl = IPDEFTTL;
166 int ip_forwsrcrt = 0;
167 int ip_directedbcast = 0;
168 int ip_allowsrcrt = 0;
169 int ip_mtudisc = 1;
170 int ip_mtudisc_timeout = IPMTUDISCTIMEOUT;
171 int ip_do_randomid = 1;
172
173 /*
174 * XXX - Setting ip_checkinterface mostly implements the receive side of
175 * the Strong ES model described in RFC 1122, but since the routing table
176 * and transmit implementation do not implement the Strong ES model,
177 * setting this to 1 results in an odd hybrid.
178 *
179 * XXX - ip_checkinterface currently must be disabled if you use NAT
180 * to translate the destination address to another local interface.
181 *
182 * XXX - ip_checkinterface must be disabled if you add IP aliases
183 * to the loopback interface instead of the interface where the
184 * packets for those addresses are received.
185 */
186 static int ip_checkinterface __read_mostly = 0;
187
188 struct rttimer_queue *ip_mtudisc_timeout_q = NULL;
189
190 pktqueue_t * ip_pktq __read_mostly;
191 pfil_head_t * inet_pfil_hook __read_mostly;
192 percpu_t * ipstat_percpu __read_mostly;
193
194 static percpu_t *ipforward_rt_percpu __cacheline_aligned;
195
196 uint16_t ip_id;
197
198 #ifdef INET_CSUM_COUNTERS
199 #include <sys/device.h>
200
201 struct evcnt ip_hwcsum_bad = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
202 NULL, "inet", "hwcsum bad");
203 struct evcnt ip_hwcsum_ok = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
204 NULL, "inet", "hwcsum ok");
205 struct evcnt ip_swcsum = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
206 NULL, "inet", "swcsum");
207
208 #define INET_CSUM_COUNTER_INCR(ev) (ev)->ev_count++
209
210 EVCNT_ATTACH_STATIC(ip_hwcsum_bad);
211 EVCNT_ATTACH_STATIC(ip_hwcsum_ok);
212 EVCNT_ATTACH_STATIC(ip_swcsum);
213
214 #else
215
216 #define INET_CSUM_COUNTER_INCR(ev) /* nothing */
217
218 #endif /* INET_CSUM_COUNTERS */
219
220 /*
221 * Used to save the IP options in case a protocol wants to respond
222 * to an incoming packet over the same route if the packet got here
223 * using IP source routing. This allows connection establishment and
224 * maintenance when the remote end is on a network that is not known
225 * to us.
226 */
227 struct ip_srcrt {
228 int isr_nhops; /* number of hops */
229 struct in_addr isr_dst; /* final destination */
230 char isr_nop; /* one NOP to align */
231 char isr_hdr[IPOPT_OFFSET + 1]; /* OPTVAL, OLEN & OFFSET */
232 struct in_addr isr_routes[MAX_IPOPTLEN/sizeof(struct in_addr)];
233 };
234
235 static int ip_drainwanted;
236
237 static void save_rte(struct mbuf *, u_char *, struct in_addr);
238
239 #ifdef MBUFTRACE
240 struct mowner ip_rx_mowner = MOWNER_INIT("internet", "rx");
241 struct mowner ip_tx_mowner = MOWNER_INIT("internet", "tx");
242 #endif
243
244 static void ipintr(void *);
245 static void ip_input(struct mbuf *, struct ifnet *);
246 static void ip_forward(struct mbuf *, int, struct ifnet *);
247 static bool ip_dooptions(struct mbuf *);
248 static struct in_ifaddr *ip_rtaddr(struct in_addr, struct psref *);
249 static void sysctl_net_inet_ip_setup(struct sysctllog **);
250
251 static struct in_ifaddr *ip_match_our_address(struct ifnet *, struct ip *,
252 int *);
253 static struct in_ifaddr *ip_match_our_address_broadcast(struct ifnet *,
254 struct ip *);
255
256 #ifdef NET_MPSAFE
257 #define SOFTNET_LOCK() mutex_enter(softnet_lock)
258 #define SOFTNET_UNLOCK() mutex_exit(softnet_lock)
259 #else
260 #define SOFTNET_LOCK() KASSERT(mutex_owned(softnet_lock))
261 #define SOFTNET_UNLOCK() KASSERT(mutex_owned(softnet_lock))
262 #endif
263
264 /*
265 * IP initialization: fill in IP protocol switch table.
266 * All protocols not implemented in kernel go to raw IP protocol handler.
267 */
268 void
ip_init(void)269 ip_init(void)
270 {
271 const struct protosw *pr;
272
273 ip_pktq = pktq_create(IFQ_MAXLEN, ipintr, NULL);
274 KASSERT(ip_pktq != NULL);
275
276 in_init();
277 sysctl_net_inet_ip_setup(NULL);
278
279 pr = pffindproto(PF_INET, IPPROTO_RAW, SOCK_RAW);
280 KASSERT(pr != NULL);
281
282 for (u_int i = 0; i < IPPROTO_MAX; i++) {
283 ip_protox[i] = pr - inetsw;
284 }
285 for (pr = inetdomain.dom_protosw;
286 pr < inetdomain.dom_protoswNPROTOSW; pr++)
287 if (pr->pr_domain->dom_family == PF_INET &&
288 pr->pr_protocol && pr->pr_protocol != IPPROTO_RAW)
289 ip_protox[pr->pr_protocol] = pr - inetsw;
290
291 ip_reass_init();
292
293 ip_id = time_uptime & 0xfffff;
294
295 #ifdef GATEWAY
296 ipflow_init();
297 #endif
298
299 /* Register our Packet Filter hook. */
300 inet_pfil_hook = pfil_head_create(PFIL_TYPE_AF, (void *)AF_INET);
301 KASSERT(inet_pfil_hook != NULL);
302
303 #ifdef MBUFTRACE
304 MOWNER_ATTACH(&ip_tx_mowner);
305 MOWNER_ATTACH(&ip_rx_mowner);
306 #endif
307
308 ipstat_percpu = percpu_alloc(sizeof(uint64_t) * IP_NSTATS);
309 ipforward_rt_percpu = rtcache_percpu_alloc();
310 ip_mtudisc_timeout_q = rt_timer_queue_create(ip_mtudisc_timeout);
311 }
312
313 static struct in_ifaddr *
ip_match_our_address(struct ifnet * ifp,struct ip * ip,int * downmatch)314 ip_match_our_address(struct ifnet *ifp, struct ip *ip, int *downmatch)
315 {
316 struct in_ifaddr *ia = NULL;
317 int checkif;
318
319 /*
320 * Enable a consistency check between the destination address
321 * and the arrival interface for a unicast packet (the RFC 1122
322 * strong ES model) if IP forwarding is disabled and the packet
323 * is not locally generated.
324 *
325 * XXX - We need to add a per ifaddr flag for this so that
326 * we get finer grain control.
327 */
328 checkif = ip_checkinterface && (ipforwarding == 0) &&
329 (ifp->if_flags & IFF_LOOPBACK) == 0;
330
331 IN_ADDRHASH_READER_FOREACH(ia, ip->ip_dst.s_addr) {
332 if (in_hosteq(ia->ia_addr.sin_addr, ip->ip_dst)) {
333 if (ia->ia4_flags & IN_IFF_NOTREADY)
334 continue;
335 if (checkif && ia->ia_ifp != ifp)
336 continue;
337 if ((ia->ia_ifp->if_flags & IFF_UP) == 0) {
338 (*downmatch)++;
339 continue;
340 }
341 if (ia->ia4_flags & IN_IFF_DETACHED &&
342 (ifp->if_flags & IFF_LOOPBACK) == 0)
343 continue;
344 break;
345 }
346 }
347
348 return ia;
349 }
350
351 static struct in_ifaddr *
ip_match_our_address_broadcast(struct ifnet * ifp,struct ip * ip)352 ip_match_our_address_broadcast(struct ifnet *ifp, struct ip *ip)
353 {
354 struct in_ifaddr *ia = NULL;
355 struct ifaddr *ifa;
356
357 IFADDR_READER_FOREACH(ifa, ifp) {
358 if (ifa->ifa_addr->sa_family != AF_INET)
359 continue;
360 ia = ifatoia(ifa);
361 if (ia->ia4_flags & IN_IFF_NOTREADY)
362 continue;
363 if (ia->ia4_flags & IN_IFF_DETACHED &&
364 (ifp->if_flags & IFF_LOOPBACK) == 0)
365 continue;
366 if (in_hosteq(ip->ip_dst, ia->ia_broadaddr.sin_addr) ||
367 in_hosteq(ip->ip_dst, ia->ia_netbroadcast) ||
368 /*
369 * Look for all-0's host part (old broadcast addr),
370 * either for subnet or net.
371 */
372 ip->ip_dst.s_addr == ia->ia_subnet ||
373 ip->ip_dst.s_addr == ia->ia_net)
374 goto matched;
375 /*
376 * An interface with IP address zero accepts
377 * all packets that arrive on that interface.
378 */
379 if (in_nullhost(ia->ia_addr.sin_addr))
380 goto matched;
381 }
382 ia = NULL;
383
384 matched:
385 return ia;
386 }
387
388 /*
389 * IP software interrupt routine.
390 */
391 static void
ipintr(void * arg __unused)392 ipintr(void *arg __unused)
393 {
394 struct mbuf *m;
395
396 KASSERT(cpu_softintr_p());
397
398 SOFTNET_KERNEL_LOCK_UNLESS_NET_MPSAFE();
399 while ((m = pktq_dequeue(ip_pktq)) != NULL) {
400 struct ifnet *ifp;
401 struct psref psref;
402
403 ifp = m_get_rcvif_psref(m, &psref);
404 if (__predict_false(ifp == NULL)) {
405 IP_STATINC(IP_STAT_IFDROP);
406 m_freem(m);
407 continue;
408 }
409
410 ip_input(m, ifp);
411
412 m_put_rcvif_psref(ifp, &psref);
413 }
414 SOFTNET_KERNEL_UNLOCK_UNLESS_NET_MPSAFE();
415 }
416
417 /*
418 * IP input routine. Checksum and byte swap header. If fragmented
419 * try to reassemble. Process options. Pass to next level.
420 */
421 static void
ip_input(struct mbuf * m,struct ifnet * ifp)422 ip_input(struct mbuf *m, struct ifnet *ifp)
423 {
424 struct ip *ip = NULL;
425 struct in_ifaddr *ia = NULL;
426 int hlen = 0, len;
427 int downmatch;
428 int srcrt = 0;
429 int s;
430
431 KASSERTMSG(cpu_softintr_p(), "ip_input: not in the software "
432 "interrupt handler; synchronization assumptions violated");
433
434 MCLAIM(m, &ip_rx_mowner);
435 KASSERT((m->m_flags & M_PKTHDR) != 0);
436
437 /*
438 * If no IP addresses have been set yet but the interfaces
439 * are receiving, can't do anything with incoming packets yet.
440 * Note: we pre-check without locks held.
441 */
442 if (IN_ADDRLIST_READER_EMPTY()) {
443 IP_STATINC(IP_STAT_IFDROP);
444 goto out;
445 }
446
447 IP_STATINC(IP_STAT_TOTAL);
448
449 /*
450 * If the IP header is not aligned, slurp it up into a new
451 * mbuf with space for link headers, in the event we forward
452 * it. Otherwise, if it is aligned, make sure the entire
453 * base IP header is in the first mbuf of the chain.
454 */
455 if (M_GET_ALIGNED_HDR(&m, struct ip, true) != 0) {
456 /* XXXJRT new stat, please */
457 IP_STATINC(IP_STAT_TOOSMALL);
458 goto out;
459 }
460 ip = mtod(m, struct ip *);
461 if (ip->ip_v != IPVERSION) {
462 IP_STATINC(IP_STAT_BADVERS);
463 goto out;
464 }
465 hlen = ip->ip_hl << 2;
466 if (hlen < sizeof(struct ip)) { /* minimum header length */
467 IP_STATINC(IP_STAT_BADHLEN);
468 goto out;
469 }
470 if (hlen > m->m_len) {
471 if ((m = m_pullup(m, hlen)) == NULL) {
472 IP_STATINC(IP_STAT_BADHLEN);
473 goto out;
474 }
475 ip = mtod(m, struct ip *);
476 }
477
478 /*
479 * RFC1122: packets with a multicast source address are
480 * not allowed.
481 */
482 if (IN_MULTICAST(ip->ip_src.s_addr)) {
483 IP_STATINC(IP_STAT_BADADDR);
484 goto out;
485 }
486
487 /* 127/8 must not appear on wire - RFC1122 */
488 if ((ntohl(ip->ip_dst.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET ||
489 (ntohl(ip->ip_src.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET) {
490 if ((ifp->if_flags & IFF_LOOPBACK) == 0) {
491 IP_STATINC(IP_STAT_BADADDR);
492 goto out;
493 }
494 }
495
496 switch (m->m_pkthdr.csum_flags &
497 ((ifp->if_csum_flags_rx & M_CSUM_IPv4) | M_CSUM_IPv4_BAD)) {
498 case M_CSUM_IPv4|M_CSUM_IPv4_BAD:
499 INET_CSUM_COUNTER_INCR(&ip_hwcsum_bad);
500 IP_STATINC(IP_STAT_BADSUM);
501 goto out;
502
503 case M_CSUM_IPv4:
504 /* Checksum was okay. */
505 INET_CSUM_COUNTER_INCR(&ip_hwcsum_ok);
506 break;
507
508 default:
509 /*
510 * Must compute it ourselves. Maybe skip checksum on
511 * loopback interfaces.
512 */
513 if (__predict_true(!(ifp->if_flags & IFF_LOOPBACK) ||
514 ip_do_loopback_cksum)) {
515 INET_CSUM_COUNTER_INCR(&ip_swcsum);
516 if (in_cksum(m, hlen) != 0) {
517 IP_STATINC(IP_STAT_BADSUM);
518 goto out;
519 }
520 }
521 break;
522 }
523
524 /* Retrieve the packet length. */
525 len = ntohs(ip->ip_len);
526
527 /*
528 * Check for additional length bogosity
529 */
530 if (len < hlen) {
531 IP_STATINC(IP_STAT_BADLEN);
532 goto out;
533 }
534
535 /*
536 * Check that the amount of data in the buffers is at least as much
537 * as the IP header would have us expect. Trim mbufs if longer than
538 * we expect. Drop packet if shorter than we expect.
539 */
540 if (m->m_pkthdr.len < len) {
541 IP_STATINC(IP_STAT_TOOSHORT);
542 goto out;
543 }
544 if (m->m_pkthdr.len > len) {
545 if (m->m_len == m->m_pkthdr.len) {
546 m->m_len = len;
547 m->m_pkthdr.len = len;
548 } else
549 m_adj(m, len - m->m_pkthdr.len);
550 }
551
552 /*
553 * Assume that we can create a fast-forward IP flow entry
554 * based on this packet.
555 */
556 m->m_flags |= M_CANFASTFWD;
557
558 /*
559 * Run through list of hooks for input packets. If there are any
560 * filters which require that additional packets in the flow are
561 * not fast-forwarded, they must clear the M_CANFASTFWD flag.
562 * Note that filters must _never_ set this flag, as another filter
563 * in the list may have previously cleared it.
564 *
565 * Don't call hooks if the packet has already been processed by
566 * IPsec (encapsulated, tunnel mode).
567 */
568 #if defined(IPSEC)
569 if (!ipsec_used || !ipsec_skip_pfil(m))
570 #else
571 if (1)
572 #endif
573 {
574 struct in_addr odst = ip->ip_dst;
575 bool freed;
576
577 freed = pfil_run_hooks(inet_pfil_hook, &m, ifp, PFIL_IN) != 0;
578 if (freed || m == NULL) {
579 m = NULL;
580 IP_STATINC(IP_STAT_PFILDROP_IN);
581 goto out;
582 }
583 if (__predict_false(m->m_len < sizeof(struct ip))) {
584 if ((m = m_pullup(m, sizeof(struct ip))) == NULL) {
585 IP_STATINC(IP_STAT_TOOSMALL);
586 goto out;
587 }
588 }
589 ip = mtod(m, struct ip *);
590 hlen = ip->ip_hl << 2;
591 if (hlen < sizeof(struct ip)) { /* minimum header length */
592 IP_STATINC(IP_STAT_BADHLEN);
593 goto out;
594 }
595 if (hlen > m->m_len) {
596 if ((m = m_pullup(m, hlen)) == NULL) {
597 IP_STATINC(IP_STAT_BADHLEN);
598 goto out;
599 }
600 ip = mtod(m, struct ip *);
601 }
602
603 /*
604 * XXX The setting of "srcrt" here is to prevent ip_forward()
605 * from generating ICMP redirects for packets that have
606 * been redirected by a hook back out on to the same LAN that
607 * they came from and is not an indication that the packet
608 * is being influenced by source routing options. This
609 * allows things like
610 * "rdr tlp0 0/0 port 80 -> 1.1.1.200 3128 tcp"
611 * where tlp0 is both on the 1.1.1.0/24 network and is the
612 * default route for hosts on 1.1.1.0/24. Of course this
613 * also requires a "map tlp0 ..." to complete the story.
614 * One might argue whether or not this kind of network config.
615 * should be supported in this manner...
616 */
617 srcrt = (odst.s_addr != ip->ip_dst.s_addr);
618 }
619
620 #ifdef ALTQ
621 /* XXX Temporary until ALTQ is changed to use a pfil hook */
622 if (altq_input) {
623 SOFTNET_LOCK();
624 if ((*altq_input)(m, AF_INET) == 0) {
625 /* Packet dropped by traffic conditioner. */
626 SOFTNET_UNLOCK();
627 m = NULL;
628 goto out;
629 }
630 SOFTNET_UNLOCK();
631 }
632 #endif
633
634 /*
635 * Process options and, if not destined for us,
636 * ship it on. ip_dooptions returns 1 when an
637 * error was detected (causing an icmp message
638 * to be sent and the original packet to be freed).
639 */
640 if (hlen > sizeof(struct ip) && ip_dooptions(m)) {
641 m = NULL;
642 goto out;
643 }
644
645 /*
646 * Check our list of addresses, to see if the packet is for us.
647 *
648 * Traditional 4.4BSD did not consult IFF_UP at all.
649 * The behavior here is to treat addresses on !IFF_UP interface
650 * or IN_IFF_NOTREADY addresses as not mine.
651 */
652 downmatch = 0;
653 s = pserialize_read_enter();
654 ia = ip_match_our_address(ifp, ip, &downmatch);
655 if (ia != NULL) {
656 pserialize_read_exit(s);
657 goto ours;
658 }
659
660 if (ifp->if_flags & IFF_BROADCAST) {
661 ia = ip_match_our_address_broadcast(ifp, ip);
662 if (ia != NULL) {
663 pserialize_read_exit(s);
664 goto ours;
665 }
666 }
667 pserialize_read_exit(s);
668
669 if (IN_MULTICAST(ip->ip_dst.s_addr)) {
670 #ifdef MROUTING
671 extern struct socket *ip_mrouter;
672
673 if (ip_mrouter) {
674 /*
675 * If we are acting as a multicast router, all
676 * incoming multicast packets are passed to the
677 * kernel-level multicast forwarding function.
678 * The packet is returned (relatively) intact; if
679 * ip_mforward() returns a non-zero value, the packet
680 * must be discarded, else it may be accepted below.
681 *
682 * (The IP ident field is put in the same byte order
683 * as expected when ip_mforward() is called from
684 * ip_output().)
685 */
686 SOFTNET_LOCK();
687 if (ip_mforward(m, ifp) != 0) {
688 SOFTNET_UNLOCK();
689 IP_STATINC(IP_STAT_CANTFORWARD);
690 goto out;
691 }
692 SOFTNET_UNLOCK();
693
694 /*
695 * The process-level routing demon needs to receive
696 * all multicast IGMP packets, whether or not this
697 * host belongs to their destination groups.
698 */
699 if (ip->ip_p == IPPROTO_IGMP) {
700 goto ours;
701 }
702 IP_STATINC(IP_STAT_CANTFORWARD);
703 }
704 #endif
705 /*
706 * See if we belong to the destination multicast group on the
707 * arrival interface.
708 */
709 if (!in_multi_group(ip->ip_dst, ifp, 0)) {
710 IP_STATINC(IP_STAT_CANTFORWARD);
711 goto out;
712 }
713 goto ours;
714 }
715 if (ip->ip_dst.s_addr == INADDR_BROADCAST ||
716 in_nullhost(ip->ip_dst))
717 goto ours;
718
719 /*
720 * Not for us; forward if possible and desirable.
721 */
722 if (ipforwarding == 0) {
723 IP_STATINC(IP_STAT_CANTFORWARD);
724 m_freem(m);
725 } else {
726 /*
727 * If ip_dst matched any of my address on !IFF_UP interface,
728 * and there's no IFF_UP interface that matches ip_dst,
729 * send icmp unreach. Forwarding it will result in in-kernel
730 * forwarding loop till TTL goes to 0.
731 */
732 if (downmatch) {
733 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_HOST, 0, 0);
734 IP_STATINC(IP_STAT_CANTFORWARD);
735 return;
736 }
737 #ifdef IPSEC
738 /* Check the security policy (SP) for the packet */
739 if (ipsec_used) {
740 if (ipsec_ip_input_checkpolicy(m, true) != 0) {
741 IP_STATINC(IP_STAT_IPSECDROP_IN);
742 goto out;
743 }
744 }
745 #endif
746 ip_forward(m, srcrt, ifp);
747 }
748 return;
749
750 ours:
751 /*
752 * If offset or IP_MF are set, must reassemble.
753 */
754 if (ip->ip_off & ~htons(IP_DF|IP_RF)) {
755 /*
756 * Pass to IP reassembly mechanism.
757 */
758 if (ip_reass_packet(&m) != 0) {
759 /* Failed; invalid fragment(s) or packet. */
760 goto out;
761 }
762 if (m == NULL) {
763 /* More fragments should come; silently return. */
764 goto out;
765 }
766 /*
767 * Reassembly is done, we have the final packet.
768 * Update cached data in local variable(s).
769 */
770 ip = mtod(m, struct ip *);
771 hlen = ip->ip_hl << 2;
772 }
773
774 M_VERIFY_PACKET(m);
775
776 #ifdef IPSEC
777 /*
778 * Enforce IPsec policy checking if we are seeing last header.
779 * Note that we do not visit this with protocols with PCB layer
780 * code - like UDP/TCP/raw IP.
781 */
782 if (ipsec_used &&
783 (inetsw[ip_protox[ip->ip_p]].pr_flags & PR_LASTHDR) != 0) {
784 if (ipsec_ip_input_checkpolicy(m, false) != 0) {
785 IP_STATINC(IP_STAT_IPSECDROP_IN);
786 goto out;
787 }
788 }
789 #endif
790
791 /*
792 * Switch out to protocol's input routine.
793 */
794 #if IFA_STATS
795 if (ia) {
796 struct in_ifaddr *_ia;
797 /*
798 * Keep a reference from ip_match_our_address with psref
799 * is expensive, so explore ia here again.
800 */
801 s = pserialize_read_enter();
802 _ia = in_get_ia(ip->ip_dst);
803 _ia->ia_ifa.ifa_data.ifad_inbytes += ntohs(ip->ip_len);
804 pserialize_read_exit(s);
805 }
806 #endif
807 IP_STATINC(IP_STAT_DELIVERED);
808
809 const int off = hlen, nh = ip->ip_p;
810
811 (*inetsw[ip_protox[nh]].pr_input)(m, off, nh);
812 return;
813
814 out:
815 if (m != NULL)
816 m_freem(m);
817 }
818
819 /*
820 * IP timer processing.
821 */
822 void
ip_slowtimo(void)823 ip_slowtimo(void)
824 {
825
826 SOFTNET_KERNEL_LOCK_UNLESS_NET_MPSAFE();
827
828 ip_reass_slowtimo();
829
830 SOFTNET_KERNEL_UNLOCK_UNLESS_NET_MPSAFE();
831 }
832
833 /*
834 * IP drain processing.
835 */
836 void
ip_drain(void)837 ip_drain(void)
838 {
839
840 KERNEL_LOCK(1, NULL);
841 ip_reass_drain();
842 KERNEL_UNLOCK_ONE(NULL);
843 }
844
845 /*
846 * ip_dooptions: perform option processing on a datagram, possibly discarding
847 * it if bad options are encountered, or forwarding it if source-routed.
848 *
849 * => Returns true if packet has been forwarded/freed.
850 * => Returns false if the packet should be processed further.
851 */
852 static bool
ip_dooptions(struct mbuf * m)853 ip_dooptions(struct mbuf *m)
854 {
855 struct ip *ip = mtod(m, struct ip *);
856 u_char *cp, *cp0;
857 struct ip_timestamp *ipt;
858 struct in_ifaddr *ia;
859 int opt, optlen, cnt, off, code, type = ICMP_PARAMPROB, forward = 0;
860 int srr_present, rr_present, ts_present;
861 struct in_addr dst;
862 n_time ntime;
863 struct ifaddr *ifa = NULL;
864 int s;
865
866 srr_present = 0;
867 rr_present = 0;
868 ts_present = 0;
869
870 dst = ip->ip_dst;
871 cp = (u_char *)(ip + 1);
872 cnt = (ip->ip_hl << 2) - sizeof(struct ip);
873 for (; cnt > 0; cnt -= optlen, cp += optlen) {
874 opt = cp[IPOPT_OPTVAL];
875 if (opt == IPOPT_EOL)
876 break;
877 if (opt == IPOPT_NOP)
878 optlen = 1;
879 else {
880 if (cnt < IPOPT_OLEN + sizeof(*cp)) {
881 code = &cp[IPOPT_OLEN] - (u_char *)ip;
882 goto bad;
883 }
884 optlen = cp[IPOPT_OLEN];
885 if (optlen < IPOPT_OLEN + sizeof(*cp) || optlen > cnt) {
886 code = &cp[IPOPT_OLEN] - (u_char *)ip;
887 goto bad;
888 }
889 }
890 switch (opt) {
891
892 default:
893 break;
894
895 /*
896 * Source routing with record.
897 * Find interface with current destination address.
898 * If none on this machine then drop if strictly routed,
899 * or do nothing if loosely routed.
900 * Record interface address and bring up next address
901 * component. If strictly routed make sure next
902 * address is on directly accessible net.
903 */
904 case IPOPT_LSRR:
905 case IPOPT_SSRR: {
906 struct psref psref;
907 struct sockaddr_in ipaddr = {
908 .sin_len = sizeof(ipaddr),
909 .sin_family = AF_INET,
910 };
911
912 if (ip_allowsrcrt == 0) {
913 type = ICMP_UNREACH;
914 code = ICMP_UNREACH_NET_PROHIB;
915 goto bad;
916 }
917 if (srr_present++) {
918 code = &cp[IPOPT_OPTVAL] - (u_char *)ip;
919 goto bad;
920 }
921 if (optlen < IPOPT_OFFSET + sizeof(*cp)) {
922 code = &cp[IPOPT_OLEN] - (u_char *)ip;
923 goto bad;
924 }
925 if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) {
926 code = &cp[IPOPT_OFFSET] - (u_char *)ip;
927 goto bad;
928 }
929 ipaddr.sin_addr = ip->ip_dst;
930
931 s = pserialize_read_enter();
932 ifa = ifa_ifwithaddr(sintosa(&ipaddr));
933 if (ifa == NULL) {
934 pserialize_read_exit(s);
935 if (opt == IPOPT_SSRR) {
936 type = ICMP_UNREACH;
937 code = ICMP_UNREACH_SRCFAIL;
938 goto bad;
939 }
940 /*
941 * Loose routing, and not at next destination
942 * yet; nothing to do except forward.
943 */
944 break;
945 }
946 pserialize_read_exit(s);
947
948 off--; /* 0 origin */
949 if ((off + sizeof(struct in_addr)) > optlen) {
950 /*
951 * End of source route. Should be for us.
952 */
953 save_rte(m, cp, ip->ip_src);
954 break;
955 }
956 /*
957 * locate outgoing interface
958 */
959 memcpy((void *)&ipaddr.sin_addr, (void *)(cp + off),
960 sizeof(ipaddr.sin_addr));
961 if (opt == IPOPT_SSRR) {
962 ifa = ifa_ifwithladdr_psref(sintosa(&ipaddr),
963 &psref);
964 if (ifa != NULL)
965 ia = ifatoia(ifa);
966 else
967 ia = NULL;
968 } else {
969 ia = ip_rtaddr(ipaddr.sin_addr, &psref);
970 }
971 if (ia == NULL) {
972 type = ICMP_UNREACH;
973 code = ICMP_UNREACH_SRCFAIL;
974 goto bad;
975 }
976 ip->ip_dst = ipaddr.sin_addr;
977 memcpy(cp + off, &ia->ia_addr.sin_addr,
978 sizeof(struct in_addr));
979 ia4_release(ia, &psref);
980 cp[IPOPT_OFFSET] += sizeof(struct in_addr);
981 /*
982 * Let ip_intr's mcast routing check handle mcast pkts
983 */
984 forward = !IN_MULTICAST(ip->ip_dst.s_addr);
985 break;
986 }
987
988 case IPOPT_RR: {
989 struct psref psref;
990 struct sockaddr_in ipaddr = {
991 .sin_len = sizeof(ipaddr),
992 .sin_family = AF_INET,
993 };
994
995 if (rr_present++) {
996 code = &cp[IPOPT_OPTVAL] - (u_char *)ip;
997 goto bad;
998 }
999 if (optlen < IPOPT_OFFSET + sizeof(*cp)) {
1000 code = &cp[IPOPT_OLEN] - (u_char *)ip;
1001 goto bad;
1002 }
1003 if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) {
1004 code = &cp[IPOPT_OFFSET] - (u_char *)ip;
1005 goto bad;
1006 }
1007 /*
1008 * If no space remains, ignore.
1009 */
1010 off--; /* 0 origin */
1011 if ((off + sizeof(struct in_addr)) > optlen)
1012 break;
1013 memcpy((void *)&ipaddr.sin_addr, (void *)&ip->ip_dst,
1014 sizeof(ipaddr.sin_addr));
1015 /*
1016 * locate outgoing interface; if we're the destination,
1017 * use the incoming interface (should be same).
1018 */
1019 ifa = ifa_ifwithaddr_psref(sintosa(&ipaddr), &psref);
1020 if (ifa == NULL) {
1021 ia = ip_rtaddr(ipaddr.sin_addr, &psref);
1022 if (ia == NULL) {
1023 type = ICMP_UNREACH;
1024 code = ICMP_UNREACH_HOST;
1025 goto bad;
1026 }
1027 } else {
1028 ia = ifatoia(ifa);
1029 }
1030 memcpy(cp + off, &ia->ia_addr.sin_addr,
1031 sizeof(struct in_addr));
1032 ia4_release(ia, &psref);
1033 cp[IPOPT_OFFSET] += sizeof(struct in_addr);
1034 break;
1035 }
1036
1037 case IPOPT_TS:
1038 code = cp - (u_char *)ip;
1039 ipt = (struct ip_timestamp *)cp;
1040 if (ts_present++) {
1041 code = &cp[IPOPT_OPTVAL] - (u_char *)ip;
1042 goto bad;
1043 }
1044 if (ipt->ipt_len < 4 || ipt->ipt_len > 40) {
1045 code = (u_char *)&ipt->ipt_len - (u_char *)ip;
1046 goto bad;
1047 }
1048 if (ipt->ipt_ptr < 5) {
1049 code = (u_char *)&ipt->ipt_ptr - (u_char *)ip;
1050 goto bad;
1051 }
1052 if (ipt->ipt_ptr > ipt->ipt_len - sizeof(int32_t)) {
1053 if (++ipt->ipt_oflw == 0) {
1054 code = (u_char *)&ipt->ipt_ptr -
1055 (u_char *)ip;
1056 goto bad;
1057 }
1058 break;
1059 }
1060 cp0 = (cp + ipt->ipt_ptr - 1);
1061 switch (ipt->ipt_flg) {
1062
1063 case IPOPT_TS_TSONLY:
1064 break;
1065
1066 case IPOPT_TS_TSANDADDR: {
1067 struct ifnet *rcvif;
1068 int _s, _ss;
1069 struct sockaddr_in ipaddr = {
1070 .sin_len = sizeof(ipaddr),
1071 .sin_family = AF_INET,
1072 };
1073
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 _ss = pserialize_read_enter();
1082 rcvif = m_get_rcvif(m, &_s);
1083 if (__predict_true(rcvif != NULL)) {
1084 ifa = ifaof_ifpforaddr(sintosa(&ipaddr),
1085 rcvif);
1086 }
1087 m_put_rcvif(rcvif, &_s);
1088 if (ifa == NULL) {
1089 pserialize_read_exit(_ss);
1090 break;
1091 }
1092 ia = ifatoia(ifa);
1093 memcpy(cp0, &ia->ia_addr.sin_addr,
1094 sizeof(struct in_addr));
1095 pserialize_read_exit(_ss);
1096 ipt->ipt_ptr += sizeof(struct in_addr);
1097 break;
1098 }
1099
1100 case IPOPT_TS_PRESPEC: {
1101 struct sockaddr_in ipaddr = {
1102 .sin_len = sizeof(ipaddr),
1103 .sin_family = AF_INET,
1104 };
1105
1106 if (ipt->ipt_ptr - 1 + sizeof(n_time) +
1107 sizeof(struct in_addr) > ipt->ipt_len) {
1108 code = (u_char *)&ipt->ipt_ptr -
1109 (u_char *)ip;
1110 goto bad;
1111 }
1112 memcpy(&ipaddr.sin_addr, cp0,
1113 sizeof(struct in_addr));
1114 s = pserialize_read_enter();
1115 ifa = ifa_ifwithaddr(sintosa(&ipaddr));
1116 if (ifa == NULL) {
1117 pserialize_read_exit(s);
1118 continue;
1119 }
1120 pserialize_read_exit(s);
1121 ipt->ipt_ptr += sizeof(struct in_addr);
1122 break;
1123 }
1124
1125 default:
1126 /* XXX can't take &ipt->ipt_flg */
1127 code = (u_char *)&ipt->ipt_ptr -
1128 (u_char *)ip + 1;
1129 goto bad;
1130 }
1131 ntime = iptime();
1132 cp0 = (u_char *) &ntime; /* XXX grumble, GCC... */
1133 memmove((char *)cp + ipt->ipt_ptr - 1, cp0,
1134 sizeof(n_time));
1135 ipt->ipt_ptr += sizeof(n_time);
1136 }
1137 }
1138 if (forward) {
1139 struct ifnet *rcvif;
1140 struct psref _psref;
1141
1142 if (ip_forwsrcrt == 0) {
1143 type = ICMP_UNREACH;
1144 code = ICMP_UNREACH_SRCFAIL;
1145 goto bad;
1146 }
1147
1148 rcvif = m_get_rcvif_psref(m, &_psref);
1149 if (__predict_false(rcvif == NULL)) {
1150 type = ICMP_UNREACH;
1151 code = ICMP_UNREACH_HOST;
1152 goto bad;
1153 }
1154 ip_forward(m, 1, rcvif);
1155 m_put_rcvif_psref(rcvif, &_psref);
1156 return true;
1157 }
1158 return false;
1159 bad:
1160 icmp_error(m, type, code, 0, 0);
1161 IP_STATINC(IP_STAT_BADOPTIONS);
1162 return true;
1163 }
1164
1165 /*
1166 * ip_rtaddr: given address of next destination (final or next hop),
1167 * return internet address info of interface to be used to get there.
1168 */
1169 static struct in_ifaddr *
ip_rtaddr(struct in_addr dst,struct psref * psref)1170 ip_rtaddr(struct in_addr dst, struct psref *psref)
1171 {
1172 struct rtentry *rt;
1173 union {
1174 struct sockaddr dst;
1175 struct sockaddr_in dst4;
1176 } u;
1177 struct route *ro;
1178
1179 sockaddr_in_init(&u.dst4, &dst, 0);
1180
1181 ro = rtcache_percpu_getref(ipforward_rt_percpu);
1182 rt = rtcache_lookup(ro, &u.dst);
1183 if (rt == NULL) {
1184 rtcache_percpu_putref(ipforward_rt_percpu);
1185 return NULL;
1186 }
1187
1188 ia4_acquire(ifatoia(rt->rt_ifa), psref);
1189 rtcache_unref(rt, ro);
1190 rtcache_percpu_putref(ipforward_rt_percpu);
1191
1192 return ifatoia(rt->rt_ifa);
1193 }
1194
1195 /*
1196 * save_rte: save incoming source route for use in replies, to be picked
1197 * up later by ip_srcroute if the receiver is interested.
1198 */
1199 static void
save_rte(struct mbuf * m,u_char * option,struct in_addr dst)1200 save_rte(struct mbuf *m, u_char *option, struct in_addr dst)
1201 {
1202 struct ip_srcrt *isr;
1203 struct m_tag *mtag;
1204 unsigned olen;
1205
1206 olen = option[IPOPT_OLEN];
1207 if (olen > sizeof(isr->isr_hdr) + sizeof(isr->isr_routes))
1208 return;
1209
1210 mtag = m_tag_get(PACKET_TAG_SRCROUTE, sizeof(*isr), M_NOWAIT);
1211 if (mtag == NULL)
1212 return;
1213 isr = (struct ip_srcrt *)(mtag + 1);
1214
1215 memcpy(isr->isr_hdr, option, olen);
1216 isr->isr_nhops = (olen - IPOPT_OFFSET - 1) / sizeof(struct in_addr);
1217 isr->isr_dst = dst;
1218 m_tag_prepend(m, mtag);
1219 }
1220
1221 /*
1222 * Retrieve incoming source route for use in replies,
1223 * in the same form used by setsockopt.
1224 * The first hop is placed before the options, will be removed later.
1225 */
1226 struct mbuf *
ip_srcroute(struct mbuf * m0)1227 ip_srcroute(struct mbuf *m0)
1228 {
1229 struct in_addr *p, *q;
1230 struct mbuf *m;
1231 struct ip_srcrt *isr;
1232 struct m_tag *mtag;
1233
1234 mtag = m_tag_find(m0, PACKET_TAG_SRCROUTE);
1235 if (mtag == NULL)
1236 return NULL;
1237 isr = (struct ip_srcrt *)(mtag + 1);
1238
1239 if (isr->isr_nhops == 0)
1240 return NULL;
1241
1242 m = m_get(M_DONTWAIT, MT_SOOPTS);
1243 if (m == NULL)
1244 return NULL;
1245
1246 MCLAIM(m, &inetdomain.dom_mowner);
1247 #define OPTSIZ (sizeof(isr->isr_nop) + sizeof(isr->isr_hdr))
1248
1249 /* length is (nhops+1)*sizeof(addr) + sizeof(nop + header) */
1250 m->m_len = (isr->isr_nhops + 1) * sizeof(struct in_addr) + OPTSIZ;
1251
1252 /*
1253 * First save first hop for return route
1254 */
1255 p = &(isr->isr_routes[isr->isr_nhops - 1]);
1256 *(mtod(m, struct in_addr *)) = *p--;
1257
1258 /*
1259 * Copy option fields and padding (nop) to mbuf.
1260 */
1261 isr->isr_nop = IPOPT_NOP;
1262 isr->isr_hdr[IPOPT_OFFSET] = IPOPT_MINOFF;
1263 memmove(mtod(m, char *) + sizeof(struct in_addr), &isr->isr_nop,
1264 OPTSIZ);
1265 q = (struct in_addr *)(mtod(m, char *) +
1266 sizeof(struct in_addr) + OPTSIZ);
1267 #undef OPTSIZ
1268 /*
1269 * Record return path as an IP source route,
1270 * reversing the path (pointers are now aligned).
1271 */
1272 while (p >= isr->isr_routes) {
1273 *q++ = *p--;
1274 }
1275 /*
1276 * Last hop goes to final destination.
1277 */
1278 *q = isr->isr_dst;
1279 m_tag_delete(m0, mtag);
1280 return m;
1281 }
1282
1283 const int inetctlerrmap[PRC_NCMDS] = {
1284 [PRC_MSGSIZE] = EMSGSIZE,
1285 [PRC_HOSTDEAD] = EHOSTDOWN,
1286 [PRC_HOSTUNREACH] = EHOSTUNREACH,
1287 [PRC_UNREACH_NET] = EHOSTUNREACH,
1288 [PRC_UNREACH_HOST] = EHOSTUNREACH,
1289 [PRC_UNREACH_PROTOCOL] = ECONNREFUSED,
1290 [PRC_UNREACH_PORT] = ECONNREFUSED,
1291 [PRC_UNREACH_SRCFAIL] = EHOSTUNREACH,
1292 [PRC_PARAMPROB] = ENOPROTOOPT,
1293 };
1294
1295 void
ip_fasttimo(void)1296 ip_fasttimo(void)
1297 {
1298 if (ip_drainwanted) {
1299 ip_drain();
1300 ip_drainwanted = 0;
1301 }
1302 }
1303
1304 void
ip_drainstub(void)1305 ip_drainstub(void)
1306 {
1307 ip_drainwanted = 1;
1308 }
1309
1310 /*
1311 * Forward a packet. If some error occurs return the sender
1312 * an icmp packet. Note we can't always generate a meaningful
1313 * icmp message because icmp doesn't have a large enough repertoire
1314 * of codes and types.
1315 *
1316 * If not forwarding, just drop the packet. This could be confusing
1317 * if ipforwarding was zero but some routing protocol was advancing
1318 * us as a gateway to somewhere. However, we must let the routing
1319 * protocol deal with that.
1320 *
1321 * The srcrt parameter indicates whether the packet is being forwarded
1322 * via a source route.
1323 */
1324 static void
ip_forward(struct mbuf * m,int srcrt,struct ifnet * rcvif)1325 ip_forward(struct mbuf *m, int srcrt, struct ifnet *rcvif)
1326 {
1327 struct ip *ip = mtod(m, struct ip *);
1328 struct rtentry *rt;
1329 int error, type = 0, code = 0, destmtu = 0;
1330 struct mbuf *mcopy;
1331 n_long dest;
1332 union {
1333 struct sockaddr dst;
1334 struct sockaddr_in dst4;
1335 } u;
1336 uint64_t *ips;
1337 struct route *ro;
1338
1339 KASSERTMSG(cpu_softintr_p(), "ip_forward: not in the software "
1340 "interrupt handler; synchronization assumptions violated");
1341
1342 /*
1343 * We are now in the output path.
1344 */
1345 MCLAIM(m, &ip_tx_mowner);
1346
1347 /*
1348 * Clear any in-bound checksum flags for this packet.
1349 */
1350 m->m_pkthdr.csum_flags = 0;
1351
1352 dest = 0;
1353 if (m->m_flags & (M_BCAST|M_MCAST) || in_canforward(ip->ip_dst) == 0) {
1354 IP_STATINC(IP_STAT_CANTFORWARD);
1355 m_freem(m);
1356 return;
1357 }
1358
1359 if (ip->ip_ttl <= IPTTLDEC) {
1360 IP_STATINC(IP_STAT_TIMXCEED);
1361 icmp_error(m, ICMP_TIMXCEED, ICMP_TIMXCEED_INTRANS, dest, 0);
1362 return;
1363 }
1364
1365 sockaddr_in_init(&u.dst4, &ip->ip_dst, 0);
1366
1367 ro = rtcache_percpu_getref(ipforward_rt_percpu);
1368 rt = rtcache_lookup(ro, &u.dst);
1369 if (rt == NULL) {
1370 rtcache_percpu_putref(ipforward_rt_percpu);
1371 IP_STATINC(IP_STAT_NOROUTE);
1372 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_NET, dest, 0);
1373 return;
1374 }
1375
1376 /*
1377 * Save at most 68 bytes of the packet in case
1378 * we need to generate an ICMP message to the src.
1379 * Pullup to avoid sharing mbuf cluster between m and mcopy.
1380 */
1381 mcopy = m_copym(m, 0, imin(ntohs(ip->ip_len), 68), M_DONTWAIT);
1382 if (mcopy)
1383 mcopy = m_pullup(mcopy, ip->ip_hl << 2);
1384
1385 ip->ip_ttl -= IPTTLDEC;
1386
1387 /*
1388 * If forwarding packet using same interface that it came in on,
1389 * perhaps should send a redirect to sender to shortcut a hop.
1390 * Only send redirect if source is sending directly to us,
1391 * and if packet was not source routed (or has any options).
1392 * Also, don't send redirect if forwarding using a default route
1393 * or a route modified by a redirect.
1394 */
1395 if (rt->rt_ifp == rcvif &&
1396 (rt->rt_flags & (RTF_DYNAMIC|RTF_MODIFIED)) == 0 &&
1397 !in_nullhost(satocsin(rt_getkey(rt))->sin_addr) &&
1398 ipsendredirects && !srcrt) {
1399 if ((ip->ip_src.s_addr & ifatoia(rt->rt_ifa)->ia_subnetmask) ==
1400 ifatoia(rt->rt_ifa)->ia_subnet) {
1401 if (rt->rt_flags & RTF_GATEWAY)
1402 dest = satosin(rt->rt_gateway)->sin_addr.s_addr;
1403 else
1404 dest = ip->ip_dst.s_addr;
1405 /*
1406 * Router requirements says to only send host
1407 * redirects.
1408 */
1409 type = ICMP_REDIRECT;
1410 code = ICMP_REDIRECT_HOST;
1411 }
1412 }
1413 rtcache_unref(rt, ro);
1414
1415 error = ip_output(m, NULL, ro,
1416 (IP_FORWARDING | (ip_directedbcast ? IP_ALLOWBROADCAST : 0)),
1417 NULL, NULL);
1418
1419 if (error) {
1420 IP_STATINC(IP_STAT_CANTFORWARD);
1421 goto error;
1422 }
1423
1424 ips = IP_STAT_GETREF();
1425 ips[IP_STAT_FORWARD]++;
1426
1427 if (type) {
1428 ips[IP_STAT_REDIRECTSENT]++;
1429 IP_STAT_PUTREF();
1430 goto redirect;
1431 }
1432
1433 IP_STAT_PUTREF();
1434 if (mcopy) {
1435 #ifdef GATEWAY
1436 if (mcopy->m_flags & M_CANFASTFWD)
1437 ipflow_create(ro, mcopy);
1438 #endif
1439 m_freem(mcopy);
1440 }
1441
1442 rtcache_percpu_putref(ipforward_rt_percpu);
1443 return;
1444
1445 redirect:
1446 error:
1447 if (mcopy == NULL) {
1448 rtcache_percpu_putref(ipforward_rt_percpu);
1449 return;
1450 }
1451
1452 switch (error) {
1453
1454 case 0: /* forwarded, but need redirect */
1455 /* type, code set above */
1456 break;
1457
1458 case ENETUNREACH: /* shouldn't happen, checked above */
1459 case EHOSTUNREACH:
1460 case ENETDOWN:
1461 case EHOSTDOWN:
1462 default:
1463 type = ICMP_UNREACH;
1464 code = ICMP_UNREACH_HOST;
1465 break;
1466
1467 case EMSGSIZE:
1468 type = ICMP_UNREACH;
1469 code = ICMP_UNREACH_NEEDFRAG;
1470
1471 if ((rt = rtcache_validate(ro)) != NULL) {
1472 destmtu = rt->rt_ifp->if_mtu;
1473 rtcache_unref(rt, ro);
1474 }
1475 #ifdef IPSEC
1476 if (ipsec_used)
1477 ipsec_mtu(mcopy, &destmtu);
1478 #endif
1479 IP_STATINC(IP_STAT_CANTFRAG);
1480 break;
1481
1482 case ENOBUFS:
1483 /*
1484 * Do not generate ICMP_SOURCEQUENCH as required in RFC 1812,
1485 * Requirements for IP Version 4 Routers. Source quench can
1486 * be a big problem under DoS attacks or if the underlying
1487 * interface is rate-limited.
1488 */
1489 if (mcopy)
1490 m_freem(mcopy);
1491 rtcache_percpu_putref(ipforward_rt_percpu);
1492 return;
1493 }
1494 icmp_error(mcopy, type, code, dest, destmtu);
1495 rtcache_percpu_putref(ipforward_rt_percpu);
1496 }
1497
1498 void
ip_savecontrol(struct inpcb * inp,struct mbuf ** mp,struct ip * ip,struct mbuf * m)1499 ip_savecontrol(struct inpcb *inp, struct mbuf **mp, struct ip *ip,
1500 struct mbuf *m)
1501 {
1502 struct socket *so = inp->inp_socket;
1503 int inpflags = inp->inp_flags;
1504
1505 if (SOOPT_TIMESTAMP(so->so_options))
1506 mp = sbsavetimestamp(so->so_options, mp);
1507
1508 if (inpflags & INP_RECVDSTADDR) {
1509 *mp = sbcreatecontrol(&ip->ip_dst,
1510 sizeof(struct in_addr), IP_RECVDSTADDR, IPPROTO_IP);
1511 if (*mp)
1512 mp = &(*mp)->m_next;
1513 }
1514
1515 if (inpflags & INP_RECVTTL) {
1516 *mp = sbcreatecontrol(&ip->ip_ttl,
1517 sizeof(uint8_t), IP_RECVTTL, IPPROTO_IP);
1518 if (*mp)
1519 mp = &(*mp)->m_next;
1520 }
1521
1522 struct psref psref;
1523 ifnet_t *ifp = m_get_rcvif_psref(m, &psref);
1524 if (__predict_false(ifp == NULL)) {
1525 #ifdef DIAGNOSTIC
1526 printf("%s: missing receive interface\n", __func__);
1527 #endif
1528 return; /* XXX should report error? */
1529 }
1530
1531 if (inpflags & INP_RECVPKTINFO) {
1532 struct in_pktinfo ipi;
1533 ipi.ipi_addr = ip->ip_dst;
1534 ipi.ipi_ifindex = ifp->if_index;
1535 *mp = sbcreatecontrol(&ipi,
1536 sizeof(ipi), IP_PKTINFO, IPPROTO_IP);
1537 if (*mp)
1538 mp = &(*mp)->m_next;
1539 }
1540 if (inpflags & INP_RECVIF) {
1541 struct sockaddr_dl sdl;
1542
1543 sockaddr_dl_init(&sdl, sizeof(sdl), ifp->if_index, 0, NULL, 0,
1544 NULL, 0);
1545 *mp = sbcreatecontrol(&sdl, sdl.sdl_len, IP_RECVIF, IPPROTO_IP);
1546 if (*mp)
1547 mp = &(*mp)->m_next;
1548 }
1549 m_put_rcvif_psref(ifp, &psref);
1550 }
1551
1552 /*
1553 * sysctl helper routine for net.inet.ip.forwsrcrt.
1554 */
1555 static int
sysctl_net_inet_ip_forwsrcrt(SYSCTLFN_ARGS)1556 sysctl_net_inet_ip_forwsrcrt(SYSCTLFN_ARGS)
1557 {
1558 int error, tmp;
1559 struct sysctlnode node;
1560
1561 node = *rnode;
1562 tmp = ip_forwsrcrt;
1563 node.sysctl_data = &tmp;
1564 error = sysctl_lookup(SYSCTLFN_CALL(&node));
1565 if (error || newp == NULL)
1566 return (error);
1567
1568 error = kauth_authorize_network(l->l_cred, KAUTH_NETWORK_FORWSRCRT,
1569 0, NULL, NULL, NULL);
1570 if (error)
1571 return (error);
1572
1573 ip_forwsrcrt = tmp;
1574
1575 return (0);
1576 }
1577
1578 /*
1579 * sysctl helper routine for net.inet.ip.mtudisctimeout. checks the
1580 * range of the new value and tweaks timers if it changes.
1581 */
1582 static int
sysctl_net_inet_ip_pmtudto(SYSCTLFN_ARGS)1583 sysctl_net_inet_ip_pmtudto(SYSCTLFN_ARGS)
1584 {
1585 int error, tmp;
1586 struct sysctlnode node;
1587
1588 icmp_mtudisc_lock();
1589
1590 node = *rnode;
1591 tmp = ip_mtudisc_timeout;
1592 node.sysctl_data = &tmp;
1593 error = sysctl_lookup(SYSCTLFN_CALL(&node));
1594 if (error || newp == NULL)
1595 goto out;
1596 if (tmp < 0) {
1597 error = EINVAL;
1598 goto out;
1599 }
1600
1601 ip_mtudisc_timeout = tmp;
1602 rt_timer_queue_change(ip_mtudisc_timeout_q, ip_mtudisc_timeout);
1603 error = 0;
1604 out:
1605 icmp_mtudisc_unlock();
1606 return error;
1607 }
1608
1609 static int
sysctl_net_inet_ip_stats(SYSCTLFN_ARGS)1610 sysctl_net_inet_ip_stats(SYSCTLFN_ARGS)
1611 {
1612
1613 return (NETSTAT_SYSCTL(ipstat_percpu, IP_NSTATS));
1614 }
1615
1616 static void
sysctl_net_inet_ip_setup(struct sysctllog ** clog)1617 sysctl_net_inet_ip_setup(struct sysctllog **clog)
1618 {
1619 const struct sysctlnode *ip_node;
1620
1621 sysctl_createv(clog, 0, NULL, NULL,
1622 CTLFLAG_PERMANENT,
1623 CTLTYPE_NODE, "inet",
1624 SYSCTL_DESCR("PF_INET related settings"),
1625 NULL, 0, NULL, 0,
1626 CTL_NET, PF_INET, CTL_EOL);
1627 sysctl_createv(clog, 0, NULL, &ip_node,
1628 CTLFLAG_PERMANENT,
1629 CTLTYPE_NODE, "ip",
1630 SYSCTL_DESCR("IPv4 related settings"),
1631 NULL, 0, NULL, 0,
1632 CTL_NET, PF_INET, IPPROTO_IP, CTL_EOL);
1633
1634 sysctl_createv(clog, 0, NULL, NULL,
1635 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1636 CTLTYPE_INT, "forwarding",
1637 SYSCTL_DESCR("Enable forwarding of INET datagrams"),
1638 NULL, 0, &ipforwarding, 0,
1639 CTL_NET, PF_INET, IPPROTO_IP,
1640 IPCTL_FORWARDING, CTL_EOL);
1641 sysctl_createv(clog, 0, NULL, NULL,
1642 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1643 CTLTYPE_INT, "redirect",
1644 SYSCTL_DESCR("Enable sending of ICMP redirect messages"),
1645 NULL, 0, &ipsendredirects, 0,
1646 CTL_NET, PF_INET, IPPROTO_IP,
1647 IPCTL_SENDREDIRECTS, CTL_EOL);
1648 sysctl_createv(clog, 0, NULL, NULL,
1649 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1650 CTLTYPE_INT, "ttl",
1651 SYSCTL_DESCR("Default TTL for an INET datagram"),
1652 NULL, 0, &ip_defttl, 0,
1653 CTL_NET, PF_INET, IPPROTO_IP,
1654 IPCTL_DEFTTL, CTL_EOL);
1655 sysctl_createv(clog, 0, NULL, NULL,
1656 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1657 CTLTYPE_INT, "forwsrcrt",
1658 SYSCTL_DESCR("Enable forwarding of source-routed "
1659 "datagrams"),
1660 sysctl_net_inet_ip_forwsrcrt, 0, &ip_forwsrcrt, 0,
1661 CTL_NET, PF_INET, IPPROTO_IP,
1662 IPCTL_FORWSRCRT, CTL_EOL);
1663 sysctl_createv(clog, 0, NULL, NULL,
1664 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1665 CTLTYPE_INT, "directed-broadcast",
1666 SYSCTL_DESCR("Enable forwarding of broadcast datagrams"),
1667 NULL, 0, &ip_directedbcast, 0,
1668 CTL_NET, PF_INET, IPPROTO_IP,
1669 IPCTL_DIRECTEDBCAST, CTL_EOL);
1670 sysctl_createv(clog, 0, NULL, NULL,
1671 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1672 CTLTYPE_INT, "allowsrcrt",
1673 SYSCTL_DESCR("Accept source-routed datagrams"),
1674 NULL, 0, &ip_allowsrcrt, 0,
1675 CTL_NET, PF_INET, IPPROTO_IP,
1676 IPCTL_ALLOWSRCRT, CTL_EOL);
1677
1678 sysctl_createv(clog, 0, NULL, NULL,
1679 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1680 CTLTYPE_INT, "mtudisc",
1681 SYSCTL_DESCR("Use RFC1191 Path MTU Discovery"),
1682 NULL, 0, &ip_mtudisc, 0,
1683 CTL_NET, PF_INET, IPPROTO_IP,
1684 IPCTL_MTUDISC, CTL_EOL);
1685 sysctl_createv(clog, 0, NULL, NULL,
1686 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1687 CTLTYPE_INT, "anonportmin",
1688 SYSCTL_DESCR("Lowest ephemeral port number to assign"),
1689 sysctl_net_inet_ip_ports, 0, &anonportmin, 0,
1690 CTL_NET, PF_INET, IPPROTO_IP,
1691 IPCTL_ANONPORTMIN, CTL_EOL);
1692 sysctl_createv(clog, 0, NULL, NULL,
1693 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1694 CTLTYPE_INT, "anonportmax",
1695 SYSCTL_DESCR("Highest ephemeral port number to assign"),
1696 sysctl_net_inet_ip_ports, 0, &anonportmax, 0,
1697 CTL_NET, PF_INET, IPPROTO_IP,
1698 IPCTL_ANONPORTMAX, CTL_EOL);
1699 sysctl_createv(clog, 0, NULL, NULL,
1700 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1701 CTLTYPE_INT, "mtudisctimeout",
1702 SYSCTL_DESCR("Lifetime of a Path MTU Discovered route"),
1703 sysctl_net_inet_ip_pmtudto, 0, (void *)&ip_mtudisc_timeout, 0,
1704 CTL_NET, PF_INET, IPPROTO_IP,
1705 IPCTL_MTUDISCTIMEOUT, CTL_EOL);
1706 #ifndef IPNOPRIVPORTS
1707 sysctl_createv(clog, 0, NULL, NULL,
1708 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1709 CTLTYPE_INT, "lowportmin",
1710 SYSCTL_DESCR("Lowest privileged ephemeral port number "
1711 "to assign"),
1712 sysctl_net_inet_ip_ports, 0, &lowportmin, 0,
1713 CTL_NET, PF_INET, IPPROTO_IP,
1714 IPCTL_LOWPORTMIN, CTL_EOL);
1715 sysctl_createv(clog, 0, NULL, NULL,
1716 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1717 CTLTYPE_INT, "lowportmax",
1718 SYSCTL_DESCR("Highest privileged ephemeral port number "
1719 "to assign"),
1720 sysctl_net_inet_ip_ports, 0, &lowportmax, 0,
1721 CTL_NET, PF_INET, IPPROTO_IP,
1722 IPCTL_LOWPORTMAX, CTL_EOL);
1723 #endif /* IPNOPRIVPORTS */
1724 #if NGRE > 0
1725 sysctl_createv(clog, 0, NULL, NULL,
1726 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1727 CTLTYPE_INT, "grettl",
1728 SYSCTL_DESCR("Default TTL for a gre tunnel datagram"),
1729 NULL, 0, &ip_gre_ttl, 0,
1730 CTL_NET, PF_INET, IPPROTO_IP,
1731 IPCTL_GRE_TTL, CTL_EOL);
1732 #endif /* NGRE */
1733 sysctl_createv(clog, 0, NULL, NULL,
1734 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1735 CTLTYPE_INT, "checkinterface",
1736 SYSCTL_DESCR("Enable receive side of Strong ES model "
1737 "from RFC1122"),
1738 NULL, 0, &ip_checkinterface, 0,
1739 CTL_NET, PF_INET, IPPROTO_IP,
1740 IPCTL_CHECKINTERFACE, CTL_EOL);
1741
1742 pktq_sysctl_setup(ip_pktq, clog, ip_node, IPCTL_IFQ);
1743
1744 sysctl_createv(clog, 0, NULL, NULL,
1745 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1746 CTLTYPE_INT, "random_id",
1747 SYSCTL_DESCR("Assign random ip_id values"),
1748 NULL, 0, &ip_do_randomid, 0,
1749 CTL_NET, PF_INET, IPPROTO_IP,
1750 IPCTL_RANDOMID, CTL_EOL);
1751 sysctl_createv(clog, 0, NULL, NULL,
1752 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1753 CTLTYPE_INT, "do_loopback_cksum",
1754 SYSCTL_DESCR("Perform IP checksum on loopback"),
1755 NULL, 0, &ip_do_loopback_cksum, 0,
1756 CTL_NET, PF_INET, IPPROTO_IP,
1757 IPCTL_LOOPBACKCKSUM, CTL_EOL);
1758 sysctl_createv(clog, 0, NULL, NULL,
1759 CTLFLAG_PERMANENT,
1760 CTLTYPE_STRUCT, "stats",
1761 SYSCTL_DESCR("IP statistics"),
1762 sysctl_net_inet_ip_stats, 0, NULL, 0,
1763 CTL_NET, PF_INET, IPPROTO_IP, IPCTL_STATS,
1764 CTL_EOL);
1765 #if NARP
1766 sysctl_createv(clog, 0, NULL, NULL,
1767 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1768 CTLTYPE_INT, "dad_count",
1769 SYSCTL_DESCR("Number of Duplicate Address Detection "
1770 "probes to send"),
1771 NULL, 0, &ip_dad_count, 0,
1772 CTL_NET, PF_INET, IPPROTO_IP,
1773 IPCTL_DAD_COUNT, CTL_EOL);
1774 #endif
1775
1776 /* anonportalgo RFC6056 subtree */
1777 const struct sysctlnode *portalgo_node;
1778 sysctl_createv(clog, 0, NULL, &portalgo_node,
1779 CTLFLAG_PERMANENT,
1780 CTLTYPE_NODE, "anonportalgo",
1781 SYSCTL_DESCR("Anonymous Port Algorithm Selection (RFC 6056)"),
1782 NULL, 0, NULL, 0,
1783 CTL_NET, PF_INET, IPPROTO_IP, CTL_CREATE, CTL_EOL);
1784 sysctl_createv(clog, 0, &portalgo_node, NULL,
1785 CTLFLAG_PERMANENT,
1786 CTLTYPE_STRING, "available",
1787 SYSCTL_DESCR("available algorithms"),
1788 sysctl_portalgo_available, 0, NULL, PORTALGO_MAXLEN,
1789 CTL_CREATE, CTL_EOL);
1790 sysctl_createv(clog, 0, &portalgo_node, NULL,
1791 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1792 CTLTYPE_STRING, "selected",
1793 SYSCTL_DESCR("selected algorithm"),
1794 sysctl_portalgo_selected4, 0, NULL, PORTALGO_MAXLEN,
1795 CTL_CREATE, CTL_EOL);
1796 sysctl_createv(clog, 0, &portalgo_node, NULL,
1797 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1798 CTLTYPE_STRUCT, "reserve",
1799 SYSCTL_DESCR("bitmap of reserved ports"),
1800 sysctl_portalgo_reserve4, 0, NULL, 0,
1801 CTL_CREATE, CTL_EOL);
1802 }
1803
1804 void
ip_statinc(u_int stat)1805 ip_statinc(u_int stat)
1806 {
1807
1808 KASSERT(stat < IP_NSTATS);
1809 IP_STATINC(stat);
1810 }
1811