ip_input.c revision 1.170 1 /* $NetBSD: ip_input.c,v 1.170 2003/07/03 05:03:53 itojun 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 * 3. All advertising materials mentioning features or use of this software
49 * must display the following acknowledgement:
50 * This product includes software developed by the NetBSD
51 * Foundation, Inc. and its contributors.
52 * 4. Neither the name of The NetBSD Foundation nor the names of its
53 * contributors may be used to endorse or promote products derived
54 * from this software without specific prior written permission.
55 *
56 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
57 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
58 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
59 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
60 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
61 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
62 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
63 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
64 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
65 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
66 * POSSIBILITY OF SUCH DAMAGE.
67 */
68
69 /*
70 * Copyright (c) 1982, 1986, 1988, 1993
71 * The Regents of the University of California. All rights reserved.
72 *
73 * Redistribution and use in source and binary forms, with or without
74 * modification, are permitted provided that the following conditions
75 * are met:
76 * 1. Redistributions of source code must retain the above copyright
77 * notice, this list of conditions and the following disclaimer.
78 * 2. Redistributions in binary form must reproduce the above copyright
79 * notice, this list of conditions and the following disclaimer in the
80 * documentation and/or other materials provided with the distribution.
81 * 3. All advertising materials mentioning features or use of this software
82 * must display the following acknowledgement:
83 * This product includes software developed by the University of
84 * California, Berkeley and its contributors.
85 * 4. Neither the name of the University nor the names of its contributors
86 * may be used to endorse or promote products derived from this software
87 * without specific prior written permission.
88 *
89 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
90 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
91 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
92 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
93 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
94 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
95 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
96 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
97 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
98 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
99 * SUCH DAMAGE.
100 *
101 * @(#)ip_input.c 8.2 (Berkeley) 1/4/94
102 */
103
104 #include <sys/cdefs.h>
105 __KERNEL_RCSID(0, "$NetBSD: ip_input.c,v 1.170 2003/07/03 05:03:53 itojun Exp $");
106
107 #include "opt_gateway.h"
108 #include "opt_pfil_hooks.h"
109 #include "opt_ipsec.h"
110 #include "opt_mrouting.h"
111 #include "opt_mbuftrace.h"
112 #include "opt_inet_csum.h"
113
114 #include <sys/param.h>
115 #include <sys/systm.h>
116 #include <sys/malloc.h>
117 #include <sys/mbuf.h>
118 #include <sys/domain.h>
119 #include <sys/protosw.h>
120 #include <sys/socket.h>
121 #include <sys/socketvar.h>
122 #include <sys/errno.h>
123 #include <sys/time.h>
124 #include <sys/kernel.h>
125 #include <sys/pool.h>
126 #include <sys/sysctl.h>
127
128 #include <net/if.h>
129 #include <net/if_dl.h>
130 #include <net/route.h>
131 #include <net/pfil.h>
132
133 #include <netinet/in.h>
134 #include <netinet/in_systm.h>
135 #include <netinet/ip.h>
136 #include <netinet/in_pcb.h>
137 #include <netinet/in_var.h>
138 #include <netinet/ip_var.h>
139 #include <netinet/ip_icmp.h>
140 /* just for gif_ttl */
141 #include <netinet/in_gif.h>
142 #include "gif.h"
143 #include <net/if_gre.h>
144 #include "gre.h"
145
146 #ifdef MROUTING
147 #include <netinet/ip_mroute.h>
148 #endif
149
150 #ifdef IPSEC
151 #include <netinet6/ipsec.h>
152 #include <netkey/key.h>
153 #endif
154
155 #ifndef IPFORWARDING
156 #ifdef GATEWAY
157 #define IPFORWARDING 1 /* forward IP packets not for us */
158 #else /* GATEWAY */
159 #define IPFORWARDING 0 /* don't forward IP packets not for us */
160 #endif /* GATEWAY */
161 #endif /* IPFORWARDING */
162 #ifndef IPSENDREDIRECTS
163 #define IPSENDREDIRECTS 1
164 #endif
165 #ifndef IPFORWSRCRT
166 #define IPFORWSRCRT 1 /* forward source-routed packets */
167 #endif
168 #ifndef IPALLOWSRCRT
169 #define IPALLOWSRCRT 1 /* allow source-routed packets */
170 #endif
171 #ifndef IPMTUDISC
172 #define IPMTUDISC 1
173 #endif
174 #ifndef IPMTUDISCTIMEOUT
175 #define IPMTUDISCTIMEOUT (10 * 60) /* as per RFC 1191 */
176 #endif
177
178 /*
179 * Note: DIRECTED_BROADCAST is handled this way so that previous
180 * configuration using this option will Just Work.
181 */
182 #ifndef IPDIRECTEDBCAST
183 #ifdef DIRECTED_BROADCAST
184 #define IPDIRECTEDBCAST 1
185 #else
186 #define IPDIRECTEDBCAST 0
187 #endif /* DIRECTED_BROADCAST */
188 #endif /* IPDIRECTEDBCAST */
189 int ipforwarding = IPFORWARDING;
190 int ipsendredirects = IPSENDREDIRECTS;
191 int ip_defttl = IPDEFTTL;
192 int ip_forwsrcrt = IPFORWSRCRT;
193 int ip_directedbcast = IPDIRECTEDBCAST;
194 int ip_allowsrcrt = IPALLOWSRCRT;
195 int ip_mtudisc = IPMTUDISC;
196 int ip_mtudisc_timeout = IPMTUDISCTIMEOUT;
197 #ifdef DIAGNOSTIC
198 int ipprintfs = 0;
199 #endif
200 /*
201 * XXX - Setting ip_checkinterface mostly implements the receive side of
202 * the Strong ES model described in RFC 1122, but since the routing table
203 * and transmit implementation do not implement the Strong ES model,
204 * setting this to 1 results in an odd hybrid.
205 *
206 * XXX - ip_checkinterface currently must be disabled if you use ipnat
207 * to translate the destination address to another local interface.
208 *
209 * XXX - ip_checkinterface must be disabled if you add IP aliases
210 * to the loopback interface instead of the interface where the
211 * packets for those addresses are received.
212 */
213 int ip_checkinterface = 0;
214
215
216 struct rttimer_queue *ip_mtudisc_timeout_q = NULL;
217
218 extern struct domain inetdomain;
219 int ipqmaxlen = IFQ_MAXLEN;
220 u_long in_ifaddrhash; /* size of hash table - 1 */
221 int in_ifaddrentries; /* total number of addrs */
222 struct in_ifaddrhead in_ifaddr;
223 struct in_ifaddrhashhead *in_ifaddrhashtbl;
224 u_long in_multihash; /* size of hash table - 1 */
225 int in_multientries; /* total number of addrs */
226 struct in_multihead in_multi;
227 struct in_multihashhead *in_multihashtbl;
228 struct ifqueue ipintrq;
229 struct ipstat ipstat;
230 u_int16_t ip_id;
231
232 #ifdef PFIL_HOOKS
233 struct pfil_head inet_pfil_hook;
234 #endif
235
236 struct ipqhead ipq;
237 int ipq_locked;
238 int ip_nfragpackets = 0;
239 int ip_maxfragpackets = 200;
240
241 static __inline int ipq_lock_try __P((void));
242 static __inline void ipq_unlock __P((void));
243
244 static __inline int
245 ipq_lock_try()
246 {
247 int s;
248
249 /*
250 * Use splvm() -- we're blocking things that would cause
251 * mbuf allocation.
252 */
253 s = splvm();
254 if (ipq_locked) {
255 splx(s);
256 return (0);
257 }
258 ipq_locked = 1;
259 splx(s);
260 return (1);
261 }
262
263 static __inline void
264 ipq_unlock()
265 {
266 int s;
267
268 s = splvm();
269 ipq_locked = 0;
270 splx(s);
271 }
272
273 #ifdef DIAGNOSTIC
274 #define IPQ_LOCK() \
275 do { \
276 if (ipq_lock_try() == 0) { \
277 printf("%s:%d: ipq already locked\n", __FILE__, __LINE__); \
278 panic("ipq_lock"); \
279 } \
280 } while (/*CONSTCOND*/ 0)
281 #define IPQ_LOCK_CHECK() \
282 do { \
283 if (ipq_locked == 0) { \
284 printf("%s:%d: ipq lock not held\n", __FILE__, __LINE__); \
285 panic("ipq lock check"); \
286 } \
287 } while (/*CONSTCOND*/ 0)
288 #else
289 #define IPQ_LOCK() (void) ipq_lock_try()
290 #define IPQ_LOCK_CHECK() /* nothing */
291 #endif
292
293 #define IPQ_UNLOCK() ipq_unlock()
294
295 struct pool inmulti_pool;
296 struct pool ipqent_pool;
297
298 #ifdef INET_CSUM_COUNTERS
299 #include <sys/device.h>
300
301 struct evcnt ip_hwcsum_bad = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
302 NULL, "inet", "hwcsum bad");
303 struct evcnt ip_hwcsum_ok = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
304 NULL, "inet", "hwcsum ok");
305 struct evcnt ip_swcsum = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
306 NULL, "inet", "swcsum");
307
308 #define INET_CSUM_COUNTER_INCR(ev) (ev)->ev_count++
309
310 #else
311
312 #define INET_CSUM_COUNTER_INCR(ev) /* nothing */
313
314 #endif /* INET_CSUM_COUNTERS */
315
316 /*
317 * We need to save the IP options in case a protocol wants to respond
318 * to an incoming packet over the same route if the packet got here
319 * using IP source routing. This allows connection establishment and
320 * maintenance when the remote end is on a network that is not known
321 * to us.
322 */
323 int ip_nhops = 0;
324 static struct ip_srcrt {
325 struct in_addr dst; /* final destination */
326 char nop; /* one NOP to align */
327 char srcopt[IPOPT_OFFSET + 1]; /* OPTVAL, OLEN and OFFSET */
328 struct in_addr route[MAX_IPOPTLEN/sizeof(struct in_addr)];
329 } ip_srcrt;
330
331 static void save_rte __P((u_char *, struct in_addr));
332
333 #ifdef MBUFTRACE
334 struct mowner ip_rx_mowner = { "internet", "rx" };
335 struct mowner ip_tx_mowner = { "internet", "tx" };
336 #endif
337
338 /*
339 * IP initialization: fill in IP protocol switch table.
340 * All protocols not implemented in kernel go to raw IP protocol handler.
341 */
342 void
343 ip_init()
344 {
345 struct protosw *pr;
346 int i;
347
348 pool_init(&inmulti_pool, sizeof(struct in_multi), 0, 0, 0, "inmltpl",
349 NULL);
350 pool_init(&ipqent_pool, sizeof(struct ipqent), 0, 0, 0, "ipqepl",
351 NULL);
352
353 pr = pffindproto(PF_INET, IPPROTO_RAW, SOCK_RAW);
354 if (pr == 0)
355 panic("ip_init");
356 for (i = 0; i < IPPROTO_MAX; i++)
357 ip_protox[i] = pr - inetsw;
358 for (pr = inetdomain.dom_protosw;
359 pr < inetdomain.dom_protoswNPROTOSW; pr++)
360 if (pr->pr_domain->dom_family == PF_INET &&
361 pr->pr_protocol && pr->pr_protocol != IPPROTO_RAW)
362 ip_protox[pr->pr_protocol] = pr - inetsw;
363 LIST_INIT(&ipq);
364 ip_id = time.tv_sec & 0xffff;
365 ipintrq.ifq_maxlen = ipqmaxlen;
366 TAILQ_INIT(&in_ifaddr);
367 in_ifaddrhashtbl = hashinit(IN_IFADDR_HASH_SIZE, HASH_LIST, M_IFADDR,
368 M_WAITOK, &in_ifaddrhash);
369 in_multihashtbl = hashinit(IN_IFADDR_HASH_SIZE, HASH_LIST, M_IPMADDR,
370 M_WAITOK, &in_multihash);
371 ip_mtudisc_timeout_q = rt_timer_queue_create(ip_mtudisc_timeout);
372 #ifdef GATEWAY
373 ipflow_init();
374 #endif
375
376 #ifdef PFIL_HOOKS
377 /* Register our Packet Filter hook. */
378 inet_pfil_hook.ph_type = PFIL_TYPE_AF;
379 inet_pfil_hook.ph_af = AF_INET;
380 i = pfil_head_register(&inet_pfil_hook);
381 if (i != 0)
382 printf("ip_init: WARNING: unable to register pfil hook, "
383 "error %d\n", i);
384 #endif /* PFIL_HOOKS */
385
386 #ifdef INET_CSUM_COUNTERS
387 evcnt_attach_static(&ip_hwcsum_bad);
388 evcnt_attach_static(&ip_hwcsum_ok);
389 evcnt_attach_static(&ip_swcsum);
390 #endif /* INET_CSUM_COUNTERS */
391
392 #ifdef MBUFTRACE
393 MOWNER_ATTACH(&ip_tx_mowner);
394 MOWNER_ATTACH(&ip_rx_mowner);
395 #endif /* MBUFTRACE */
396 }
397
398 struct sockaddr_in ipaddr = { sizeof(ipaddr), AF_INET };
399 struct route ipforward_rt;
400
401 /*
402 * IP software interrupt routine
403 */
404 void
405 ipintr()
406 {
407 int s;
408 struct mbuf *m;
409
410 while (1) {
411 s = splnet();
412 IF_DEQUEUE(&ipintrq, m);
413 splx(s);
414 if (m == 0)
415 return;
416 MCLAIM(m, &ip_rx_mowner);
417 ip_input(m);
418 }
419 }
420
421 /*
422 * Ip input routine. Checksum and byte swap header. If fragmented
423 * try to reassemble. Process options. Pass to next level.
424 */
425 void
426 ip_input(struct mbuf *m)
427 {
428 struct ip *ip = NULL;
429 struct ipq *fp;
430 struct in_ifaddr *ia;
431 struct ifaddr *ifa;
432 struct ipqent *ipqe;
433 int hlen = 0, mff, len;
434 int downmatch;
435 int checkif;
436 int srcrt = 0;
437
438 MCLAIM(m, &ip_rx_mowner);
439 #ifdef DIAGNOSTIC
440 if ((m->m_flags & M_PKTHDR) == 0)
441 panic("ipintr no HDR");
442 #endif
443 #ifdef IPSEC
444 /*
445 * should the inner packet be considered authentic?
446 * see comment in ah4_input().
447 */
448 if (m) {
449 m->m_flags &= ~M_AUTHIPHDR;
450 m->m_flags &= ~M_AUTHIPDGM;
451 }
452 #endif
453
454 /*
455 * If no IP addresses have been set yet but the interfaces
456 * are receiving, can't do anything with incoming packets yet.
457 */
458 if (TAILQ_FIRST(&in_ifaddr) == 0)
459 goto bad;
460 ipstat.ips_total++;
461 /*
462 * If the IP header is not aligned, slurp it up into a new
463 * mbuf with space for link headers, in the event we forward
464 * it. Otherwise, if it is aligned, make sure the entire
465 * base IP header is in the first mbuf of the chain.
466 */
467 if (IP_HDR_ALIGNED_P(mtod(m, caddr_t)) == 0) {
468 if ((m = m_copyup(m, sizeof(struct ip),
469 (max_linkhdr + 3) & ~3)) == NULL) {
470 /* XXXJRT new stat, please */
471 ipstat.ips_toosmall++;
472 return;
473 }
474 } else if (__predict_false(m->m_len < sizeof (struct ip))) {
475 if ((m = m_pullup(m, sizeof (struct ip))) == NULL) {
476 ipstat.ips_toosmall++;
477 return;
478 }
479 }
480 ip = mtod(m, struct ip *);
481 if (ip->ip_v != IPVERSION) {
482 ipstat.ips_badvers++;
483 goto bad;
484 }
485 hlen = ip->ip_hl << 2;
486 if (hlen < sizeof(struct ip)) { /* minimum header length */
487 ipstat.ips_badhlen++;
488 goto bad;
489 }
490 if (hlen > m->m_len) {
491 if ((m = m_pullup(m, hlen)) == 0) {
492 ipstat.ips_badhlen++;
493 return;
494 }
495 ip = mtod(m, struct ip *);
496 }
497
498 /*
499 * RFC1122: packets with a multicast source address are
500 * not allowed.
501 */
502 if (IN_MULTICAST(ip->ip_src.s_addr)) {
503 ipstat.ips_badaddr++;
504 goto bad;
505 }
506
507 /* 127/8 must not appear on wire - RFC1122 */
508 if ((ntohl(ip->ip_dst.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET ||
509 (ntohl(ip->ip_src.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET) {
510 if ((m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) == 0) {
511 ipstat.ips_badaddr++;
512 goto bad;
513 }
514 }
515
516 switch (m->m_pkthdr.csum_flags &
517 ((m->m_pkthdr.rcvif->if_csum_flags_rx & M_CSUM_IPv4) |
518 M_CSUM_IPv4_BAD)) {
519 case M_CSUM_IPv4|M_CSUM_IPv4_BAD:
520 INET_CSUM_COUNTER_INCR(&ip_hwcsum_bad);
521 goto badcsum;
522
523 case M_CSUM_IPv4:
524 /* Checksum was okay. */
525 INET_CSUM_COUNTER_INCR(&ip_hwcsum_ok);
526 break;
527
528 default:
529 /* Must compute it ourselves. */
530 INET_CSUM_COUNTER_INCR(&ip_swcsum);
531 if (in_cksum(m, hlen) != 0)
532 goto bad;
533 break;
534 }
535
536 /* Retrieve the packet length. */
537 len = ntohs(ip->ip_len);
538
539 /*
540 * Check for additional length bogosity
541 */
542 if (len < hlen) {
543 ipstat.ips_badlen++;
544 goto bad;
545 }
546
547 /*
548 * Check that the amount of data in the buffers
549 * is as at least much as the IP header would have us expect.
550 * Trim mbufs if longer than we expect.
551 * Drop packet if shorter than we expect.
552 */
553 if (m->m_pkthdr.len < len) {
554 ipstat.ips_tooshort++;
555 goto bad;
556 }
557 if (m->m_pkthdr.len > len) {
558 if (m->m_len == m->m_pkthdr.len) {
559 m->m_len = len;
560 m->m_pkthdr.len = len;
561 } else
562 m_adj(m, len - m->m_pkthdr.len);
563 }
564
565 #ifdef IPSEC
566 /* ipflow (IP fast forwarding) is not compatible with IPsec. */
567 m->m_flags &= ~M_CANFASTFWD;
568 #else
569 /*
570 * Assume that we can create a fast-forward IP flow entry
571 * based on this packet.
572 */
573 m->m_flags |= M_CANFASTFWD;
574 #endif
575
576 #ifdef PFIL_HOOKS
577 /*
578 * Run through list of hooks for input packets. If there are any
579 * filters which require that additional packets in the flow are
580 * not fast-forwarded, they must clear the M_CANFASTFWD flag.
581 * Note that filters must _never_ set this flag, as another filter
582 * in the list may have previously cleared it.
583 */
584 /*
585 * let ipfilter look at packet on the wire,
586 * not the decapsulated packet.
587 */
588 #ifdef IPSEC
589 if (!ipsec_getnhist(m))
590 #else
591 if (1)
592 #endif
593 {
594 struct in_addr odst;
595
596 odst = ip->ip_dst;
597 if (pfil_run_hooks(&inet_pfil_hook, &m, m->m_pkthdr.rcvif,
598 PFIL_IN) != 0)
599 return;
600 if (m == NULL)
601 return;
602 ip = mtod(m, struct ip *);
603 hlen = ip->ip_hl << 2;
604 srcrt = (odst.s_addr != ip->ip_dst.s_addr);
605 }
606 #endif /* PFIL_HOOKS */
607
608 #ifdef ALTQ
609 /* XXX Temporary until ALTQ is changed to use a pfil hook */
610 if (altq_input != NULL && (*altq_input)(m, AF_INET) == 0) {
611 /* packet dropped by traffic conditioner */
612 return;
613 }
614 #endif
615
616 /*
617 * Process options and, if not destined for us,
618 * ship it on. ip_dooptions returns 1 when an
619 * error was detected (causing an icmp message
620 * to be sent and the original packet to be freed).
621 */
622 ip_nhops = 0; /* for source routed packets */
623 if (hlen > sizeof (struct ip) && ip_dooptions(m))
624 return;
625
626 /*
627 * Enable a consistency check between the destination address
628 * and the arrival interface for a unicast packet (the RFC 1122
629 * strong ES model) if IP forwarding is disabled and the packet
630 * is not locally generated.
631 *
632 * XXX - Checking also should be disabled if the destination
633 * address is ipnat'ed to a different interface.
634 *
635 * XXX - Checking is incompatible with IP aliases added
636 * to the loopback interface instead of the interface where
637 * the packets are received.
638 *
639 * XXX - We need to add a per ifaddr flag for this so that
640 * we get finer grain control.
641 */
642 checkif = ip_checkinterface && (ipforwarding == 0) &&
643 (m->m_pkthdr.rcvif != NULL) &&
644 ((m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) == 0);
645
646 /*
647 * Check our list of addresses, to see if the packet is for us.
648 *
649 * Traditional 4.4BSD did not consult IFF_UP at all.
650 * The behavior here is to treat addresses on !IFF_UP interface
651 * as not mine.
652 */
653 downmatch = 0;
654 LIST_FOREACH(ia, &IN_IFADDR_HASH(ip->ip_dst.s_addr), ia_hash) {
655 if (in_hosteq(ia->ia_addr.sin_addr, ip->ip_dst)) {
656 if (checkif && ia->ia_ifp != m->m_pkthdr.rcvif)
657 continue;
658 if ((ia->ia_ifp->if_flags & IFF_UP) != 0)
659 break;
660 else
661 downmatch++;
662 }
663 }
664 if (ia != NULL)
665 goto ours;
666 if (m->m_pkthdr.rcvif->if_flags & IFF_BROADCAST) {
667 TAILQ_FOREACH(ifa, &m->m_pkthdr.rcvif->if_addrlist, ifa_list) {
668 if (ifa->ifa_addr->sa_family != AF_INET)
669 continue;
670 ia = ifatoia(ifa);
671 if (in_hosteq(ip->ip_dst, ia->ia_broadaddr.sin_addr) ||
672 in_hosteq(ip->ip_dst, ia->ia_netbroadcast) ||
673 /*
674 * Look for all-0's host part (old broadcast addr),
675 * either for subnet or net.
676 */
677 ip->ip_dst.s_addr == ia->ia_subnet ||
678 ip->ip_dst.s_addr == ia->ia_net)
679 goto ours;
680 /*
681 * An interface with IP address zero accepts
682 * all packets that arrive on that interface.
683 */
684 if (in_nullhost(ia->ia_addr.sin_addr))
685 goto ours;
686 }
687 }
688 if (IN_MULTICAST(ip->ip_dst.s_addr)) {
689 struct in_multi *inm;
690 #ifdef MROUTING
691 extern struct socket *ip_mrouter;
692
693 if (M_READONLY(m)) {
694 if ((m = m_pullup(m, hlen)) == 0) {
695 ipstat.ips_toosmall++;
696 return;
697 }
698 ip = mtod(m, struct ip *);
699 }
700
701 if (ip_mrouter) {
702 /*
703 * If we are acting as a multicast router, all
704 * incoming multicast packets are passed to the
705 * kernel-level multicast forwarding function.
706 * The packet is returned (relatively) intact; if
707 * ip_mforward() returns a non-zero value, the packet
708 * must be discarded, else it may be accepted below.
709 *
710 * (The IP ident field is put in the same byte order
711 * as expected when ip_mforward() is called from
712 * ip_output().)
713 */
714 if (ip_mforward(m, m->m_pkthdr.rcvif) != 0) {
715 ipstat.ips_cantforward++;
716 m_freem(m);
717 return;
718 }
719
720 /*
721 * The process-level routing demon needs to receive
722 * all multicast IGMP packets, whether or not this
723 * host belongs to their destination groups.
724 */
725 if (ip->ip_p == IPPROTO_IGMP)
726 goto ours;
727 ipstat.ips_forward++;
728 }
729 #endif
730 /*
731 * See if we belong to the destination multicast group on the
732 * arrival interface.
733 */
734 IN_LOOKUP_MULTI(ip->ip_dst, m->m_pkthdr.rcvif, inm);
735 if (inm == NULL) {
736 ipstat.ips_cantforward++;
737 m_freem(m);
738 return;
739 }
740 goto ours;
741 }
742 if (ip->ip_dst.s_addr == INADDR_BROADCAST ||
743 in_nullhost(ip->ip_dst))
744 goto ours;
745
746 /*
747 * Not for us; forward if possible and desirable.
748 */
749 if (ipforwarding == 0) {
750 ipstat.ips_cantforward++;
751 m_freem(m);
752 } else {
753 /*
754 * If ip_dst matched any of my address on !IFF_UP interface,
755 * and there's no IFF_UP interface that matches ip_dst,
756 * send icmp unreach. Forwarding it will result in in-kernel
757 * forwarding loop till TTL goes to 0.
758 */
759 if (downmatch) {
760 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_HOST, 0, 0);
761 ipstat.ips_cantforward++;
762 return;
763 }
764 #ifdef IPSEC
765 if (ipsec4_in_reject(m, NULL)) {
766 ipsecstat.in_polvio++;
767 goto bad;
768 }
769 #endif
770
771 ip_forward(m, srcrt);
772 }
773 return;
774
775 ours:
776 /*
777 * If offset or IP_MF are set, must reassemble.
778 * Otherwise, nothing need be done.
779 * (We could look in the reassembly queue to see
780 * if the packet was previously fragmented,
781 * but it's not worth the time; just let them time out.)
782 */
783 if (ip->ip_off & ~htons(IP_DF|IP_RF)) {
784 if (M_READONLY(m)) {
785 if ((m = m_pullup(m, hlen)) == NULL) {
786 ipstat.ips_toosmall++;
787 goto bad;
788 }
789 ip = mtod(m, struct ip *);
790 }
791
792 /*
793 * Look for queue of fragments
794 * of this datagram.
795 */
796 IPQ_LOCK();
797 LIST_FOREACH(fp, &ipq, ipq_q)
798 if (ip->ip_id == fp->ipq_id &&
799 in_hosteq(ip->ip_src, fp->ipq_src) &&
800 in_hosteq(ip->ip_dst, fp->ipq_dst) &&
801 ip->ip_p == fp->ipq_p)
802 goto found;
803 fp = 0;
804 found:
805
806 /*
807 * Adjust ip_len to not reflect header,
808 * set ipqe_mff if more fragments are expected,
809 * convert offset of this to bytes.
810 */
811 ip->ip_len = htons(ntohs(ip->ip_len) - hlen);
812 mff = (ip->ip_off & htons(IP_MF)) != 0;
813 if (mff) {
814 /*
815 * Make sure that fragments have a data length
816 * that's a non-zero multiple of 8 bytes.
817 */
818 if (ntohs(ip->ip_len) == 0 ||
819 (ntohs(ip->ip_len) & 0x7) != 0) {
820 ipstat.ips_badfrags++;
821 IPQ_UNLOCK();
822 goto bad;
823 }
824 }
825 ip->ip_off = htons((ntohs(ip->ip_off) & IP_OFFMASK) << 3);
826
827 /*
828 * If datagram marked as having more fragments
829 * or if this is not the first fragment,
830 * attempt reassembly; if it succeeds, proceed.
831 */
832 if (mff || ip->ip_off != htons(0)) {
833 ipstat.ips_fragments++;
834 ipqe = pool_get(&ipqent_pool, PR_NOWAIT);
835 if (ipqe == NULL) {
836 ipstat.ips_rcvmemdrop++;
837 IPQ_UNLOCK();
838 goto bad;
839 }
840 ipqe->ipqe_mff = mff;
841 ipqe->ipqe_m = m;
842 ipqe->ipqe_ip = ip;
843 m = ip_reass(ipqe, fp);
844 if (m == 0) {
845 IPQ_UNLOCK();
846 return;
847 }
848 ipstat.ips_reassembled++;
849 ip = mtod(m, struct ip *);
850 hlen = ip->ip_hl << 2;
851 ip->ip_len = htons(ntohs(ip->ip_len) + hlen);
852 } else
853 if (fp)
854 ip_freef(fp);
855 IPQ_UNLOCK();
856 }
857
858 #ifdef IPSEC
859 /*
860 * enforce IPsec policy checking if we are seeing last header.
861 * note that we do not visit this with protocols with pcb layer
862 * code - like udp/tcp/raw ip.
863 */
864 if ((inetsw[ip_protox[ip->ip_p]].pr_flags & PR_LASTHDR) != 0 &&
865 ipsec4_in_reject(m, NULL)) {
866 ipsecstat.in_polvio++;
867 goto bad;
868 }
869 #endif
870
871 /*
872 * Switch out to protocol's input routine.
873 */
874 #if IFA_STATS
875 if (ia && ip)
876 ia->ia_ifa.ifa_data.ifad_inbytes += ntohs(ip->ip_len);
877 #endif
878 ipstat.ips_delivered++;
879 {
880 int off = hlen, nh = ip->ip_p;
881
882 (*inetsw[ip_protox[nh]].pr_input)(m, off, nh);
883 return;
884 }
885 bad:
886 m_freem(m);
887 return;
888
889 badcsum:
890 ipstat.ips_badsum++;
891 m_freem(m);
892 }
893
894 /*
895 * Take incoming datagram fragment and try to
896 * reassemble it into whole datagram. If a chain for
897 * reassembly of this datagram already exists, then it
898 * is given as fp; otherwise have to make a chain.
899 */
900 struct mbuf *
901 ip_reass(ipqe, fp)
902 struct ipqent *ipqe;
903 struct ipq *fp;
904 {
905 struct mbuf *m = ipqe->ipqe_m;
906 struct ipqent *nq, *p, *q;
907 struct ip *ip;
908 struct mbuf *t;
909 int hlen = ipqe->ipqe_ip->ip_hl << 2;
910 int i, next;
911
912 IPQ_LOCK_CHECK();
913
914 /*
915 * Presence of header sizes in mbufs
916 * would confuse code below.
917 */
918 m->m_data += hlen;
919 m->m_len -= hlen;
920
921 /*
922 * If first fragment to arrive, create a reassembly queue.
923 */
924 if (fp == 0) {
925 /*
926 * Enforce upper bound on number of fragmented packets
927 * for which we attempt reassembly;
928 * If maxfrag is 0, never accept fragments.
929 * If maxfrag is -1, accept all fragments without limitation.
930 */
931 if (ip_maxfragpackets < 0)
932 ;
933 else if (ip_nfragpackets >= ip_maxfragpackets)
934 goto dropfrag;
935 ip_nfragpackets++;
936 MALLOC(fp, struct ipq *, sizeof (struct ipq),
937 M_FTABLE, M_NOWAIT);
938 if (fp == NULL)
939 goto dropfrag;
940 LIST_INSERT_HEAD(&ipq, fp, ipq_q);
941 fp->ipq_ttl = IPFRAGTTL;
942 fp->ipq_p = ipqe->ipqe_ip->ip_p;
943 fp->ipq_id = ipqe->ipqe_ip->ip_id;
944 TAILQ_INIT(&fp->ipq_fragq);
945 fp->ipq_src = ipqe->ipqe_ip->ip_src;
946 fp->ipq_dst = ipqe->ipqe_ip->ip_dst;
947 p = NULL;
948 goto insert;
949 }
950
951 /*
952 * Find a segment which begins after this one does.
953 */
954 for (p = NULL, q = TAILQ_FIRST(&fp->ipq_fragq); q != NULL;
955 p = q, q = TAILQ_NEXT(q, ipqe_q))
956 if (ntohs(q->ipqe_ip->ip_off) > ntohs(ipqe->ipqe_ip->ip_off))
957 break;
958
959 /*
960 * If there is a preceding segment, it may provide some of
961 * our data already. If so, drop the data from the incoming
962 * segment. If it provides all of our data, drop us.
963 */
964 if (p != NULL) {
965 i = ntohs(p->ipqe_ip->ip_off) + ntohs(p->ipqe_ip->ip_len) -
966 ntohs(ipqe->ipqe_ip->ip_off);
967 if (i > 0) {
968 if (i >= ntohs(ipqe->ipqe_ip->ip_len))
969 goto dropfrag;
970 m_adj(ipqe->ipqe_m, i);
971 ipqe->ipqe_ip->ip_off =
972 htons(ntohs(ipqe->ipqe_ip->ip_off) + i);
973 ipqe->ipqe_ip->ip_len =
974 htons(ntohs(ipqe->ipqe_ip->ip_len) - i);
975 }
976 }
977
978 /*
979 * While we overlap succeeding segments trim them or,
980 * if they are completely covered, dequeue them.
981 */
982 for (; q != NULL &&
983 ntohs(ipqe->ipqe_ip->ip_off) + ntohs(ipqe->ipqe_ip->ip_len) >
984 ntohs(q->ipqe_ip->ip_off); q = nq) {
985 i = (ntohs(ipqe->ipqe_ip->ip_off) +
986 ntohs(ipqe->ipqe_ip->ip_len)) - ntohs(q->ipqe_ip->ip_off);
987 if (i < ntohs(q->ipqe_ip->ip_len)) {
988 q->ipqe_ip->ip_len =
989 htons(ntohs(q->ipqe_ip->ip_len) - i);
990 q->ipqe_ip->ip_off =
991 htons(ntohs(q->ipqe_ip->ip_off) + i);
992 m_adj(q->ipqe_m, i);
993 break;
994 }
995 nq = TAILQ_NEXT(q, ipqe_q);
996 m_freem(q->ipqe_m);
997 TAILQ_REMOVE(&fp->ipq_fragq, q, ipqe_q);
998 pool_put(&ipqent_pool, q);
999 }
1000
1001 insert:
1002 /*
1003 * Stick new segment in its place;
1004 * check for complete reassembly.
1005 */
1006 if (p == NULL) {
1007 TAILQ_INSERT_HEAD(&fp->ipq_fragq, ipqe, ipqe_q);
1008 } else {
1009 TAILQ_INSERT_AFTER(&fp->ipq_fragq, p, ipqe, ipqe_q);
1010 }
1011 next = 0;
1012 for (p = NULL, q = TAILQ_FIRST(&fp->ipq_fragq); q != NULL;
1013 p = q, q = TAILQ_NEXT(q, ipqe_q)) {
1014 if (ntohs(q->ipqe_ip->ip_off) != next)
1015 return (0);
1016 next += ntohs(q->ipqe_ip->ip_len);
1017 }
1018 if (p->ipqe_mff)
1019 return (0);
1020
1021 /*
1022 * Reassembly is complete. Check for a bogus message size and
1023 * concatenate fragments.
1024 */
1025 q = TAILQ_FIRST(&fp->ipq_fragq);
1026 ip = q->ipqe_ip;
1027 if ((next + (ip->ip_hl << 2)) > IP_MAXPACKET) {
1028 ipstat.ips_toolong++;
1029 ip_freef(fp);
1030 return (0);
1031 }
1032 m = q->ipqe_m;
1033 t = m->m_next;
1034 m->m_next = 0;
1035 m_cat(m, t);
1036 nq = TAILQ_NEXT(q, ipqe_q);
1037 pool_put(&ipqent_pool, q);
1038 for (q = nq; q != NULL; q = nq) {
1039 t = q->ipqe_m;
1040 nq = TAILQ_NEXT(q, ipqe_q);
1041 pool_put(&ipqent_pool, q);
1042 m_cat(m, t);
1043 }
1044
1045 /*
1046 * Create header for new ip packet by
1047 * modifying header of first packet;
1048 * dequeue and discard fragment reassembly header.
1049 * Make header visible.
1050 */
1051 ip->ip_len = htons(next);
1052 ip->ip_src = fp->ipq_src;
1053 ip->ip_dst = fp->ipq_dst;
1054 LIST_REMOVE(fp, ipq_q);
1055 FREE(fp, M_FTABLE);
1056 ip_nfragpackets--;
1057 m->m_len += (ip->ip_hl << 2);
1058 m->m_data -= (ip->ip_hl << 2);
1059 /* some debugging cruft by sklower, below, will go away soon */
1060 if (m->m_flags & M_PKTHDR) { /* XXX this should be done elsewhere */
1061 int plen = 0;
1062 for (t = m; t; t = t->m_next)
1063 plen += t->m_len;
1064 m->m_pkthdr.len = plen;
1065 }
1066 return (m);
1067
1068 dropfrag:
1069 ipstat.ips_fragdropped++;
1070 m_freem(m);
1071 pool_put(&ipqent_pool, ipqe);
1072 return (0);
1073 }
1074
1075 /*
1076 * Free a fragment reassembly header and all
1077 * associated datagrams.
1078 */
1079 void
1080 ip_freef(fp)
1081 struct ipq *fp;
1082 {
1083 struct ipqent *q, *p;
1084
1085 IPQ_LOCK_CHECK();
1086
1087 for (q = TAILQ_FIRST(&fp->ipq_fragq); q != NULL; q = p) {
1088 p = TAILQ_NEXT(q, ipqe_q);
1089 m_freem(q->ipqe_m);
1090 TAILQ_REMOVE(&fp->ipq_fragq, q, ipqe_q);
1091 pool_put(&ipqent_pool, q);
1092 }
1093 LIST_REMOVE(fp, ipq_q);
1094 FREE(fp, M_FTABLE);
1095 ip_nfragpackets--;
1096 }
1097
1098 /*
1099 * IP timer processing;
1100 * if a timer expires on a reassembly
1101 * queue, discard it.
1102 */
1103 void
1104 ip_slowtimo()
1105 {
1106 struct ipq *fp, *nfp;
1107 int s = splsoftnet();
1108
1109 IPQ_LOCK();
1110 for (fp = LIST_FIRST(&ipq); fp != NULL; fp = nfp) {
1111 nfp = LIST_NEXT(fp, ipq_q);
1112 if (--fp->ipq_ttl == 0) {
1113 ipstat.ips_fragtimeout++;
1114 ip_freef(fp);
1115 }
1116 }
1117 /*
1118 * If we are over the maximum number of fragments
1119 * (due to the limit being lowered), drain off
1120 * enough to get down to the new limit.
1121 */
1122 if (ip_maxfragpackets < 0)
1123 ;
1124 else {
1125 while (ip_nfragpackets > ip_maxfragpackets && LIST_FIRST(&ipq))
1126 ip_freef(LIST_FIRST(&ipq));
1127 }
1128 IPQ_UNLOCK();
1129 #ifdef GATEWAY
1130 ipflow_slowtimo();
1131 #endif
1132 splx(s);
1133 }
1134
1135 /*
1136 * Drain off all datagram fragments.
1137 */
1138 void
1139 ip_drain()
1140 {
1141
1142 /*
1143 * We may be called from a device's interrupt context. If
1144 * the ipq is already busy, just bail out now.
1145 */
1146 if (ipq_lock_try() == 0)
1147 return;
1148
1149 while (LIST_FIRST(&ipq) != NULL) {
1150 ipstat.ips_fragdropped++;
1151 ip_freef(LIST_FIRST(&ipq));
1152 }
1153
1154 IPQ_UNLOCK();
1155 }
1156
1157 /*
1158 * Do option processing on a datagram,
1159 * possibly discarding it if bad options are encountered,
1160 * or forwarding it if source-routed.
1161 * Returns 1 if packet has been forwarded/freed,
1162 * 0 if the packet should be processed further.
1163 */
1164 int
1165 ip_dooptions(m)
1166 struct mbuf *m;
1167 {
1168 struct ip *ip = mtod(m, struct ip *);
1169 u_char *cp, *cp0;
1170 struct ip_timestamp *ipt;
1171 struct in_ifaddr *ia;
1172 int opt, optlen, cnt, off, code, type = ICMP_PARAMPROB, forward = 0;
1173 struct in_addr dst;
1174 n_time ntime;
1175
1176 dst = ip->ip_dst;
1177 cp = (u_char *)(ip + 1);
1178 cnt = (ip->ip_hl << 2) - sizeof (struct ip);
1179 for (; cnt > 0; cnt -= optlen, cp += optlen) {
1180 opt = cp[IPOPT_OPTVAL];
1181 if (opt == IPOPT_EOL)
1182 break;
1183 if (opt == IPOPT_NOP)
1184 optlen = 1;
1185 else {
1186 if (cnt < IPOPT_OLEN + sizeof(*cp)) {
1187 code = &cp[IPOPT_OLEN] - (u_char *)ip;
1188 goto bad;
1189 }
1190 optlen = cp[IPOPT_OLEN];
1191 if (optlen < IPOPT_OLEN + sizeof(*cp) || optlen > cnt) {
1192 code = &cp[IPOPT_OLEN] - (u_char *)ip;
1193 goto bad;
1194 }
1195 }
1196 switch (opt) {
1197
1198 default:
1199 break;
1200
1201 /*
1202 * Source routing with record.
1203 * Find interface with current destination address.
1204 * If none on this machine then drop if strictly routed,
1205 * or do nothing if loosely routed.
1206 * Record interface address and bring up next address
1207 * component. If strictly routed make sure next
1208 * address is on directly accessible net.
1209 */
1210 case IPOPT_LSRR:
1211 case IPOPT_SSRR:
1212 if (ip_allowsrcrt == 0) {
1213 type = ICMP_UNREACH;
1214 code = ICMP_UNREACH_NET_PROHIB;
1215 goto bad;
1216 }
1217 if (optlen < IPOPT_OFFSET + sizeof(*cp)) {
1218 code = &cp[IPOPT_OLEN] - (u_char *)ip;
1219 goto bad;
1220 }
1221 if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) {
1222 code = &cp[IPOPT_OFFSET] - (u_char *)ip;
1223 goto bad;
1224 }
1225 ipaddr.sin_addr = ip->ip_dst;
1226 ia = ifatoia(ifa_ifwithaddr(sintosa(&ipaddr)));
1227 if (ia == 0) {
1228 if (opt == IPOPT_SSRR) {
1229 type = ICMP_UNREACH;
1230 code = ICMP_UNREACH_SRCFAIL;
1231 goto bad;
1232 }
1233 /*
1234 * Loose routing, and not at next destination
1235 * yet; nothing to do except forward.
1236 */
1237 break;
1238 }
1239 off--; /* 0 origin */
1240 if ((off + sizeof(struct in_addr)) > optlen) {
1241 /*
1242 * End of source route. Should be for us.
1243 */
1244 save_rte(cp, ip->ip_src);
1245 break;
1246 }
1247 /*
1248 * locate outgoing interface
1249 */
1250 bcopy((caddr_t)(cp + off), (caddr_t)&ipaddr.sin_addr,
1251 sizeof(ipaddr.sin_addr));
1252 if (opt == IPOPT_SSRR)
1253 ia = ifatoia(ifa_ifwithaddr(sintosa(&ipaddr)));
1254 else
1255 ia = ip_rtaddr(ipaddr.sin_addr);
1256 if (ia == 0) {
1257 type = ICMP_UNREACH;
1258 code = ICMP_UNREACH_SRCFAIL;
1259 goto bad;
1260 }
1261 ip->ip_dst = ipaddr.sin_addr;
1262 bcopy((caddr_t)&ia->ia_addr.sin_addr,
1263 (caddr_t)(cp + off), sizeof(struct in_addr));
1264 cp[IPOPT_OFFSET] += sizeof(struct in_addr);
1265 /*
1266 * Let ip_intr's mcast routing check handle mcast pkts
1267 */
1268 forward = !IN_MULTICAST(ip->ip_dst.s_addr);
1269 break;
1270
1271 case IPOPT_RR:
1272 if (optlen < IPOPT_OFFSET + sizeof(*cp)) {
1273 code = &cp[IPOPT_OLEN] - (u_char *)ip;
1274 goto bad;
1275 }
1276 if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) {
1277 code = &cp[IPOPT_OFFSET] - (u_char *)ip;
1278 goto bad;
1279 }
1280 /*
1281 * If no space remains, ignore.
1282 */
1283 off--; /* 0 origin */
1284 if ((off + sizeof(struct in_addr)) > optlen)
1285 break;
1286 bcopy((caddr_t)(&ip->ip_dst), (caddr_t)&ipaddr.sin_addr,
1287 sizeof(ipaddr.sin_addr));
1288 /*
1289 * locate outgoing interface; if we're the destination,
1290 * use the incoming interface (should be same).
1291 */
1292 if ((ia = ifatoia(ifa_ifwithaddr(sintosa(&ipaddr))))
1293 == NULL &&
1294 (ia = ip_rtaddr(ipaddr.sin_addr)) == NULL) {
1295 type = ICMP_UNREACH;
1296 code = ICMP_UNREACH_HOST;
1297 goto bad;
1298 }
1299 bcopy((caddr_t)&ia->ia_addr.sin_addr,
1300 (caddr_t)(cp + off), sizeof(struct in_addr));
1301 cp[IPOPT_OFFSET] += sizeof(struct in_addr);
1302 break;
1303
1304 case IPOPT_TS:
1305 code = cp - (u_char *)ip;
1306 ipt = (struct ip_timestamp *)cp;
1307 if (ipt->ipt_len < 4 || ipt->ipt_len > 40) {
1308 code = (u_char *)&ipt->ipt_len - (u_char *)ip;
1309 goto bad;
1310 }
1311 if (ipt->ipt_ptr < 5) {
1312 code = (u_char *)&ipt->ipt_ptr - (u_char *)ip;
1313 goto bad;
1314 }
1315 if (ipt->ipt_ptr > ipt->ipt_len - sizeof (int32_t)) {
1316 if (++ipt->ipt_oflw == 0) {
1317 code = (u_char *)&ipt->ipt_ptr -
1318 (u_char *)ip;
1319 goto bad;
1320 }
1321 break;
1322 }
1323 cp0 = (cp + ipt->ipt_ptr - 1);
1324 switch (ipt->ipt_flg) {
1325
1326 case IPOPT_TS_TSONLY:
1327 break;
1328
1329 case IPOPT_TS_TSANDADDR:
1330 if (ipt->ipt_ptr - 1 + sizeof(n_time) +
1331 sizeof(struct in_addr) > ipt->ipt_len) {
1332 code = (u_char *)&ipt->ipt_ptr -
1333 (u_char *)ip;
1334 goto bad;
1335 }
1336 ipaddr.sin_addr = dst;
1337 ia = ifatoia(ifaof_ifpforaddr(sintosa(&ipaddr),
1338 m->m_pkthdr.rcvif));
1339 if (ia == 0)
1340 continue;
1341 bcopy(&ia->ia_addr.sin_addr,
1342 cp0, sizeof(struct in_addr));
1343 ipt->ipt_ptr += sizeof(struct in_addr);
1344 break;
1345
1346 case IPOPT_TS_PRESPEC:
1347 if (ipt->ipt_ptr - 1 + sizeof(n_time) +
1348 sizeof(struct in_addr) > ipt->ipt_len) {
1349 code = (u_char *)&ipt->ipt_ptr -
1350 (u_char *)ip;
1351 goto bad;
1352 }
1353 bcopy(cp0, &ipaddr.sin_addr,
1354 sizeof(struct in_addr));
1355 if (ifatoia(ifa_ifwithaddr(sintosa(&ipaddr)))
1356 == NULL)
1357 continue;
1358 ipt->ipt_ptr += sizeof(struct in_addr);
1359 break;
1360
1361 default:
1362 /* XXX can't take &ipt->ipt_flg */
1363 code = (u_char *)&ipt->ipt_ptr -
1364 (u_char *)ip + 1;
1365 goto bad;
1366 }
1367 ntime = iptime();
1368 cp0 = (u_char *) &ntime; /* XXX grumble, GCC... */
1369 bcopy(cp0, (caddr_t)cp + ipt->ipt_ptr - 1,
1370 sizeof(n_time));
1371 ipt->ipt_ptr += sizeof(n_time);
1372 }
1373 }
1374 if (forward) {
1375 if (ip_forwsrcrt == 0) {
1376 type = ICMP_UNREACH;
1377 code = ICMP_UNREACH_SRCFAIL;
1378 goto bad;
1379 }
1380 ip_forward(m, 1);
1381 return (1);
1382 }
1383 return (0);
1384 bad:
1385 icmp_error(m, type, code, 0, 0);
1386 ipstat.ips_badoptions++;
1387 return (1);
1388 }
1389
1390 /*
1391 * Given address of next destination (final or next hop),
1392 * return internet address info of interface to be used to get there.
1393 */
1394 struct in_ifaddr *
1395 ip_rtaddr(dst)
1396 struct in_addr dst;
1397 {
1398 struct sockaddr_in *sin;
1399
1400 sin = satosin(&ipforward_rt.ro_dst);
1401
1402 if (ipforward_rt.ro_rt == 0 || !in_hosteq(dst, sin->sin_addr)) {
1403 if (ipforward_rt.ro_rt) {
1404 RTFREE(ipforward_rt.ro_rt);
1405 ipforward_rt.ro_rt = 0;
1406 }
1407 sin->sin_family = AF_INET;
1408 sin->sin_len = sizeof(*sin);
1409 sin->sin_addr = dst;
1410
1411 rtalloc(&ipforward_rt);
1412 }
1413 if (ipforward_rt.ro_rt == 0)
1414 return ((struct in_ifaddr *)0);
1415 return (ifatoia(ipforward_rt.ro_rt->rt_ifa));
1416 }
1417
1418 /*
1419 * Save incoming source route for use in replies,
1420 * to be picked up later by ip_srcroute if the receiver is interested.
1421 */
1422 void
1423 save_rte(option, dst)
1424 u_char *option;
1425 struct in_addr dst;
1426 {
1427 unsigned olen;
1428
1429 olen = option[IPOPT_OLEN];
1430 #ifdef DIAGNOSTIC
1431 if (ipprintfs)
1432 printf("save_rte: olen %d\n", olen);
1433 #endif /* 0 */
1434 if (olen > sizeof(ip_srcrt) - (1 + sizeof(dst)))
1435 return;
1436 bcopy((caddr_t)option, (caddr_t)ip_srcrt.srcopt, olen);
1437 ip_nhops = (olen - IPOPT_OFFSET - 1) / sizeof(struct in_addr);
1438 ip_srcrt.dst = dst;
1439 }
1440
1441 /*
1442 * Retrieve incoming source route for use in replies,
1443 * in the same form used by setsockopt.
1444 * The first hop is placed before the options, will be removed later.
1445 */
1446 struct mbuf *
1447 ip_srcroute()
1448 {
1449 struct in_addr *p, *q;
1450 struct mbuf *m;
1451
1452 if (ip_nhops == 0)
1453 return ((struct mbuf *)0);
1454 m = m_get(M_DONTWAIT, MT_SOOPTS);
1455 if (m == 0)
1456 return ((struct mbuf *)0);
1457
1458 MCLAIM(m, &inetdomain.dom_mowner);
1459 #define OPTSIZ (sizeof(ip_srcrt.nop) + sizeof(ip_srcrt.srcopt))
1460
1461 /* length is (nhops+1)*sizeof(addr) + sizeof(nop + srcrt header) */
1462 m->m_len = ip_nhops * sizeof(struct in_addr) + sizeof(struct in_addr) +
1463 OPTSIZ;
1464 #ifdef DIAGNOSTIC
1465 if (ipprintfs)
1466 printf("ip_srcroute: nhops %d mlen %d", ip_nhops, m->m_len);
1467 #endif
1468
1469 /*
1470 * First save first hop for return route
1471 */
1472 p = &ip_srcrt.route[ip_nhops - 1];
1473 *(mtod(m, struct in_addr *)) = *p--;
1474 #ifdef DIAGNOSTIC
1475 if (ipprintfs)
1476 printf(" hops %x", ntohl(mtod(m, struct in_addr *)->s_addr));
1477 #endif
1478
1479 /*
1480 * Copy option fields and padding (nop) to mbuf.
1481 */
1482 ip_srcrt.nop = IPOPT_NOP;
1483 ip_srcrt.srcopt[IPOPT_OFFSET] = IPOPT_MINOFF;
1484 bcopy((caddr_t)&ip_srcrt.nop,
1485 mtod(m, caddr_t) + sizeof(struct in_addr), OPTSIZ);
1486 q = (struct in_addr *)(mtod(m, caddr_t) +
1487 sizeof(struct in_addr) + OPTSIZ);
1488 #undef OPTSIZ
1489 /*
1490 * Record return path as an IP source route,
1491 * reversing the path (pointers are now aligned).
1492 */
1493 while (p >= ip_srcrt.route) {
1494 #ifdef DIAGNOSTIC
1495 if (ipprintfs)
1496 printf(" %x", ntohl(q->s_addr));
1497 #endif
1498 *q++ = *p--;
1499 }
1500 /*
1501 * Last hop goes to final destination.
1502 */
1503 *q = ip_srcrt.dst;
1504 #ifdef DIAGNOSTIC
1505 if (ipprintfs)
1506 printf(" %x\n", ntohl(q->s_addr));
1507 #endif
1508 return (m);
1509 }
1510
1511 /*
1512 * Strip out IP options, at higher
1513 * level protocol in the kernel.
1514 * Second argument is buffer to which options
1515 * will be moved, and return value is their length.
1516 * XXX should be deleted; last arg currently ignored.
1517 */
1518 void
1519 ip_stripoptions(m, mopt)
1520 struct mbuf *m;
1521 struct mbuf *mopt;
1522 {
1523 int i;
1524 struct ip *ip = mtod(m, struct ip *);
1525 caddr_t opts;
1526 int olen;
1527
1528 olen = (ip->ip_hl << 2) - sizeof (struct ip);
1529 opts = (caddr_t)(ip + 1);
1530 i = m->m_len - (sizeof (struct ip) + olen);
1531 bcopy(opts + olen, opts, (unsigned)i);
1532 m->m_len -= olen;
1533 if (m->m_flags & M_PKTHDR)
1534 m->m_pkthdr.len -= olen;
1535 ip->ip_len = htons(ntohs(ip->ip_len) - olen);
1536 ip->ip_hl = sizeof (struct ip) >> 2;
1537 }
1538
1539 const int inetctlerrmap[PRC_NCMDS] = {
1540 0, 0, 0, 0,
1541 0, EMSGSIZE, EHOSTDOWN, EHOSTUNREACH,
1542 EHOSTUNREACH, EHOSTUNREACH, ECONNREFUSED, ECONNREFUSED,
1543 EMSGSIZE, EHOSTUNREACH, 0, 0,
1544 0, 0, 0, 0,
1545 ENOPROTOOPT
1546 };
1547
1548 /*
1549 * Forward a packet. If some error occurs return the sender
1550 * an icmp packet. Note we can't always generate a meaningful
1551 * icmp message because icmp doesn't have a large enough repertoire
1552 * of codes and types.
1553 *
1554 * If not forwarding, just drop the packet. This could be confusing
1555 * if ipforwarding was zero but some routing protocol was advancing
1556 * us as a gateway to somewhere. However, we must let the routing
1557 * protocol deal with that.
1558 *
1559 * The srcrt parameter indicates whether the packet is being forwarded
1560 * via a source route.
1561 */
1562 void
1563 ip_forward(m, srcrt)
1564 struct mbuf *m;
1565 int srcrt;
1566 {
1567 struct ip *ip = mtod(m, struct ip *);
1568 struct sockaddr_in *sin;
1569 struct rtentry *rt;
1570 int error, type = 0, code = 0;
1571 struct mbuf *mcopy;
1572 n_long dest;
1573 struct ifnet *destifp;
1574 #ifdef IPSEC
1575 struct ifnet dummyifp;
1576 #endif
1577
1578 /*
1579 * We are now in the output path.
1580 */
1581 MCLAIM(m, &ip_tx_mowner);
1582
1583 /*
1584 * Clear any in-bound checksum flags for this packet.
1585 */
1586 m->m_pkthdr.csum_flags = 0;
1587
1588 dest = 0;
1589 #ifdef DIAGNOSTIC
1590 if (ipprintfs)
1591 printf("forward: src %2.2x dst %2.2x ttl %x\n",
1592 ntohl(ip->ip_src.s_addr),
1593 ntohl(ip->ip_dst.s_addr), ip->ip_ttl);
1594 #endif
1595 if (m->m_flags & (M_BCAST|M_MCAST) || in_canforward(ip->ip_dst) == 0) {
1596 ipstat.ips_cantforward++;
1597 m_freem(m);
1598 return;
1599 }
1600 if (ip->ip_ttl <= IPTTLDEC) {
1601 icmp_error(m, ICMP_TIMXCEED, ICMP_TIMXCEED_INTRANS, dest, 0);
1602 return;
1603 }
1604 ip->ip_ttl -= IPTTLDEC;
1605
1606 sin = satosin(&ipforward_rt.ro_dst);
1607 if ((rt = ipforward_rt.ro_rt) == 0 ||
1608 !in_hosteq(ip->ip_dst, sin->sin_addr)) {
1609 if (ipforward_rt.ro_rt) {
1610 RTFREE(ipforward_rt.ro_rt);
1611 ipforward_rt.ro_rt = 0;
1612 }
1613 sin->sin_family = AF_INET;
1614 sin->sin_len = sizeof(struct sockaddr_in);
1615 sin->sin_addr = ip->ip_dst;
1616
1617 rtalloc(&ipforward_rt);
1618 if (ipforward_rt.ro_rt == 0) {
1619 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_HOST, dest, 0);
1620 return;
1621 }
1622 rt = ipforward_rt.ro_rt;
1623 }
1624
1625 /*
1626 * Save at most 68 bytes of the packet in case
1627 * we need to generate an ICMP message to the src.
1628 * Pullup to avoid sharing mbuf cluster between m and mcopy.
1629 */
1630 mcopy = m_copym(m, 0, imin(ntohs(ip->ip_len), 68), M_DONTWAIT);
1631 if (mcopy)
1632 mcopy = m_pullup(mcopy, ip->ip_hl << 2);
1633
1634 /*
1635 * If forwarding packet using same interface that it came in on,
1636 * perhaps should send a redirect to sender to shortcut a hop.
1637 * Only send redirect if source is sending directly to us,
1638 * and if packet was not source routed (or has any options).
1639 * Also, don't send redirect if forwarding using a default route
1640 * or a route modified by a redirect.
1641 */
1642 if (rt->rt_ifp == m->m_pkthdr.rcvif &&
1643 (rt->rt_flags & (RTF_DYNAMIC|RTF_MODIFIED)) == 0 &&
1644 !in_nullhost(satosin(rt_key(rt))->sin_addr) &&
1645 ipsendredirects && !srcrt) {
1646 if (rt->rt_ifa &&
1647 (ip->ip_src.s_addr & ifatoia(rt->rt_ifa)->ia_subnetmask) ==
1648 ifatoia(rt->rt_ifa)->ia_subnet) {
1649 if (rt->rt_flags & RTF_GATEWAY)
1650 dest = satosin(rt->rt_gateway)->sin_addr.s_addr;
1651 else
1652 dest = ip->ip_dst.s_addr;
1653 /*
1654 * Router requirements says to only send host
1655 * redirects.
1656 */
1657 type = ICMP_REDIRECT;
1658 code = ICMP_REDIRECT_HOST;
1659 #ifdef DIAGNOSTIC
1660 if (ipprintfs)
1661 printf("redirect (%d) to %x\n", code,
1662 (u_int32_t)dest);
1663 #endif
1664 }
1665 }
1666
1667 #ifdef IPSEC
1668 /* Don't lookup socket in forwarding case */
1669 (void)ipsec_setsocket(m, NULL);
1670 #endif
1671 error = ip_output(m, (struct mbuf *)0, &ipforward_rt,
1672 (IP_FORWARDING | (ip_directedbcast ? IP_ALLOWBROADCAST : 0)), 0);
1673 if (error)
1674 ipstat.ips_cantforward++;
1675 else {
1676 ipstat.ips_forward++;
1677 if (type)
1678 ipstat.ips_redirectsent++;
1679 else {
1680 if (mcopy) {
1681 #ifdef GATEWAY
1682 if (mcopy->m_flags & M_CANFASTFWD)
1683 ipflow_create(&ipforward_rt, mcopy);
1684 #endif
1685 m_freem(mcopy);
1686 }
1687 return;
1688 }
1689 }
1690 if (mcopy == NULL)
1691 return;
1692 destifp = NULL;
1693
1694 switch (error) {
1695
1696 case 0: /* forwarded, but need redirect */
1697 /* type, code set above */
1698 break;
1699
1700 case ENETUNREACH: /* shouldn't happen, checked above */
1701 case EHOSTUNREACH:
1702 case ENETDOWN:
1703 case EHOSTDOWN:
1704 default:
1705 type = ICMP_UNREACH;
1706 code = ICMP_UNREACH_HOST;
1707 break;
1708
1709 case EMSGSIZE:
1710 type = ICMP_UNREACH;
1711 code = ICMP_UNREACH_NEEDFRAG;
1712 #ifndef IPSEC
1713 if (ipforward_rt.ro_rt)
1714 destifp = ipforward_rt.ro_rt->rt_ifp;
1715 #else
1716 /*
1717 * If the packet is routed over IPsec tunnel, tell the
1718 * originator the tunnel MTU.
1719 * tunnel MTU = if MTU - sizeof(IP) - ESP/AH hdrsiz
1720 * XXX quickhack!!!
1721 */
1722 if (ipforward_rt.ro_rt) {
1723 struct secpolicy *sp;
1724 int ipsecerror;
1725 size_t ipsechdr;
1726 struct route *ro;
1727
1728 sp = ipsec4_getpolicybyaddr(mcopy,
1729 IPSEC_DIR_OUTBOUND, IP_FORWARDING,
1730 &ipsecerror);
1731
1732 if (sp == NULL)
1733 destifp = ipforward_rt.ro_rt->rt_ifp;
1734 else {
1735 /* count IPsec header size */
1736 ipsechdr = ipsec4_hdrsiz(mcopy,
1737 IPSEC_DIR_OUTBOUND, NULL);
1738
1739 /*
1740 * find the correct route for outer IPv4
1741 * header, compute tunnel MTU.
1742 *
1743 * XXX BUG ALERT
1744 * The "dummyifp" code relies upon the fact
1745 * that icmp_error() touches only ifp->if_mtu.
1746 */
1747 /*XXX*/
1748 destifp = NULL;
1749 if (sp->req != NULL
1750 && sp->req->sav != NULL
1751 && sp->req->sav->sah != NULL) {
1752 ro = &sp->req->sav->sah->sa_route;
1753 if (ro->ro_rt && ro->ro_rt->rt_ifp) {
1754 dummyifp.if_mtu =
1755 ro->ro_rt->rt_rmx.rmx_mtu ?
1756 ro->ro_rt->rt_rmx.rmx_mtu :
1757 ro->ro_rt->rt_ifp->if_mtu;
1758 dummyifp.if_mtu -= ipsechdr;
1759 destifp = &dummyifp;
1760 }
1761 }
1762
1763 key_freesp(sp);
1764 }
1765 }
1766 #endif /*IPSEC*/
1767 ipstat.ips_cantfrag++;
1768 break;
1769
1770 case ENOBUFS:
1771 #if 1
1772 /*
1773 * a router should not generate ICMP_SOURCEQUENCH as
1774 * required in RFC1812 Requirements for IP Version 4 Routers.
1775 * source quench could be a big problem under DoS attacks,
1776 * or if the underlying interface is rate-limited.
1777 */
1778 if (mcopy)
1779 m_freem(mcopy);
1780 return;
1781 #else
1782 type = ICMP_SOURCEQUENCH;
1783 code = 0;
1784 break;
1785 #endif
1786 }
1787 icmp_error(mcopy, type, code, dest, destifp);
1788 }
1789
1790 void
1791 ip_savecontrol(inp, mp, ip, m)
1792 struct inpcb *inp;
1793 struct mbuf **mp;
1794 struct ip *ip;
1795 struct mbuf *m;
1796 {
1797
1798 if (inp->inp_socket->so_options & SO_TIMESTAMP) {
1799 struct timeval tv;
1800
1801 microtime(&tv);
1802 *mp = sbcreatecontrol((caddr_t) &tv, sizeof(tv),
1803 SCM_TIMESTAMP, SOL_SOCKET);
1804 if (*mp)
1805 mp = &(*mp)->m_next;
1806 }
1807 if (inp->inp_flags & INP_RECVDSTADDR) {
1808 *mp = sbcreatecontrol((caddr_t) &ip->ip_dst,
1809 sizeof(struct in_addr), IP_RECVDSTADDR, IPPROTO_IP);
1810 if (*mp)
1811 mp = &(*mp)->m_next;
1812 }
1813 #ifdef notyet
1814 /*
1815 * XXX
1816 * Moving these out of udp_input() made them even more broken
1817 * than they already were.
1818 * - fenner (at) parc.xerox.com
1819 */
1820 /* options were tossed already */
1821 if (inp->inp_flags & INP_RECVOPTS) {
1822 *mp = sbcreatecontrol((caddr_t) opts_deleted_above,
1823 sizeof(struct in_addr), IP_RECVOPTS, IPPROTO_IP);
1824 if (*mp)
1825 mp = &(*mp)->m_next;
1826 }
1827 /* ip_srcroute doesn't do what we want here, need to fix */
1828 if (inp->inp_flags & INP_RECVRETOPTS) {
1829 *mp = sbcreatecontrol((caddr_t) ip_srcroute(),
1830 sizeof(struct in_addr), IP_RECVRETOPTS, IPPROTO_IP);
1831 if (*mp)
1832 mp = &(*mp)->m_next;
1833 }
1834 #endif
1835 if (inp->inp_flags & INP_RECVIF) {
1836 struct sockaddr_dl sdl;
1837
1838 sdl.sdl_len = offsetof(struct sockaddr_dl, sdl_data[0]);
1839 sdl.sdl_family = AF_LINK;
1840 sdl.sdl_index = m->m_pkthdr.rcvif ?
1841 m->m_pkthdr.rcvif->if_index : 0;
1842 sdl.sdl_nlen = sdl.sdl_alen = sdl.sdl_slen = 0;
1843 *mp = sbcreatecontrol((caddr_t) &sdl, sdl.sdl_len,
1844 IP_RECVIF, IPPROTO_IP);
1845 if (*mp)
1846 mp = &(*mp)->m_next;
1847 }
1848 }
1849
1850 int
1851 ip_sysctl(name, namelen, oldp, oldlenp, newp, newlen)
1852 int *name;
1853 u_int namelen;
1854 void *oldp;
1855 size_t *oldlenp;
1856 void *newp;
1857 size_t newlen;
1858 {
1859 extern int subnetsarelocal, hostzeroisbroadcast;
1860
1861 int error, old;
1862
1863 /* All sysctl names at this level are terminal. */
1864 if (namelen != 1)
1865 return (ENOTDIR);
1866
1867 switch (name[0]) {
1868 case IPCTL_FORWARDING:
1869 return (sysctl_int(oldp, oldlenp, newp, newlen, &ipforwarding));
1870 case IPCTL_SENDREDIRECTS:
1871 return (sysctl_int(oldp, oldlenp, newp, newlen,
1872 &ipsendredirects));
1873 case IPCTL_DEFTTL:
1874 return (sysctl_int(oldp, oldlenp, newp, newlen, &ip_defttl));
1875 #ifdef notyet
1876 case IPCTL_DEFMTU:
1877 return (sysctl_int(oldp, oldlenp, newp, newlen, &ip_mtu));
1878 #endif
1879 case IPCTL_FORWSRCRT:
1880 /* Don't allow this to change in a secure environment. */
1881 if (securelevel > 0)
1882 return (sysctl_rdint(oldp, oldlenp, newp,
1883 ip_forwsrcrt));
1884 else
1885 return (sysctl_int(oldp, oldlenp, newp, newlen,
1886 &ip_forwsrcrt));
1887 case IPCTL_DIRECTEDBCAST:
1888 return (sysctl_int(oldp, oldlenp, newp, newlen,
1889 &ip_directedbcast));
1890 case IPCTL_ALLOWSRCRT:
1891 return (sysctl_int(oldp, oldlenp, newp, newlen,
1892 &ip_allowsrcrt));
1893 case IPCTL_SUBNETSARELOCAL:
1894 return (sysctl_int(oldp, oldlenp, newp, newlen,
1895 &subnetsarelocal));
1896 case IPCTL_MTUDISC:
1897 error = sysctl_int(oldp, oldlenp, newp, newlen,
1898 &ip_mtudisc);
1899 if (error == 0 && ip_mtudisc == 0)
1900 rt_timer_queue_remove_all(ip_mtudisc_timeout_q, TRUE);
1901 return error;
1902 case IPCTL_ANONPORTMIN:
1903 old = anonportmin;
1904 error = sysctl_int(oldp, oldlenp, newp, newlen, &anonportmin);
1905 if (anonportmin >= anonportmax || anonportmin < 0
1906 || anonportmin > 65535
1907 #ifndef IPNOPRIVPORTS
1908 || anonportmin < IPPORT_RESERVED
1909 #endif
1910 ) {
1911 anonportmin = old;
1912 return (EINVAL);
1913 }
1914 return (error);
1915 case IPCTL_ANONPORTMAX:
1916 old = anonportmax;
1917 error = sysctl_int(oldp, oldlenp, newp, newlen, &anonportmax);
1918 if (anonportmin >= anonportmax || anonportmax < 0
1919 || anonportmax > 65535
1920 #ifndef IPNOPRIVPORTS
1921 || anonportmax < IPPORT_RESERVED
1922 #endif
1923 ) {
1924 anonportmax = old;
1925 return (EINVAL);
1926 }
1927 return (error);
1928 case IPCTL_MTUDISCTIMEOUT:
1929 old = ip_mtudisc_timeout;
1930 error = sysctl_int(oldp, oldlenp, newp, newlen,
1931 &ip_mtudisc_timeout);
1932 if (ip_mtudisc_timeout < 0) {
1933 ip_mtudisc_timeout = old;
1934 return (EINVAL);
1935 }
1936 if (error == 0)
1937 rt_timer_queue_change(ip_mtudisc_timeout_q,
1938 ip_mtudisc_timeout);
1939 return (error);
1940 #ifdef GATEWAY
1941 case IPCTL_MAXFLOWS:
1942 {
1943 int s;
1944
1945 error = sysctl_int(oldp, oldlenp, newp, newlen,
1946 &ip_maxflows);
1947 s = splsoftnet();
1948 ipflow_reap(0);
1949 splx(s);
1950 return (error);
1951 }
1952 #endif
1953 case IPCTL_HOSTZEROBROADCAST:
1954 return (sysctl_int(oldp, oldlenp, newp, newlen,
1955 &hostzeroisbroadcast));
1956 #if NGIF > 0
1957 case IPCTL_GIF_TTL:
1958 return (sysctl_int(oldp, oldlenp, newp, newlen,
1959 &ip_gif_ttl));
1960 #endif
1961
1962 #if NGRE > 0
1963 case IPCTL_GRE_TTL:
1964 return (sysctl_int(oldp, oldlenp, newp, newlen,
1965 &ip_gre_ttl));
1966 #endif
1967
1968 #ifndef IPNOPRIVPORTS
1969 case IPCTL_LOWPORTMIN:
1970 old = lowportmin;
1971 error = sysctl_int(oldp, oldlenp, newp, newlen, &lowportmin);
1972 if (lowportmin >= lowportmax
1973 || lowportmin > IPPORT_RESERVEDMAX
1974 || lowportmin < IPPORT_RESERVEDMIN
1975 ) {
1976 lowportmin = old;
1977 return (EINVAL);
1978 }
1979 return (error);
1980 case IPCTL_LOWPORTMAX:
1981 old = lowportmax;
1982 error = sysctl_int(oldp, oldlenp, newp, newlen, &lowportmax);
1983 if (lowportmin >= lowportmax
1984 || lowportmax > IPPORT_RESERVEDMAX
1985 || lowportmax < IPPORT_RESERVEDMIN
1986 ) {
1987 lowportmax = old;
1988 return (EINVAL);
1989 }
1990 return (error);
1991 #endif
1992
1993 case IPCTL_MAXFRAGPACKETS:
1994 return (sysctl_int(oldp, oldlenp, newp, newlen,
1995 &ip_maxfragpackets));
1996
1997 case IPCTL_CHECKINTERFACE:
1998 return (sysctl_int(oldp, oldlenp, newp, newlen,
1999 &ip_checkinterface));
2000 default:
2001 return (EOPNOTSUPP);
2002 }
2003 /* NOTREACHED */
2004 }
2005