ip_input.c revision 1.166 1 /* $NetBSD: ip_input.c,v 1.166 2003/06/15 02:49:33 matt 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 1.166 2003/06/15 02:49:33 matt 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_inet_csum.h"
112
113 #include <sys/param.h>
114 #include <sys/systm.h>
115 #include <sys/malloc.h>
116 #include <sys/mbuf.h>
117 #include <sys/domain.h>
118 #include <sys/protosw.h>
119 #include <sys/socket.h>
120 #include <sys/socketvar.h>
121 #include <sys/errno.h>
122 #include <sys/time.h>
123 #include <sys/kernel.h>
124 #include <sys/pool.h>
125 #include <sys/sysctl.h>
126
127 #include <net/if.h>
128 #include <net/if_dl.h>
129 #include <net/route.h>
130 #include <net/pfil.h>
131
132 #include <netinet/in.h>
133 #include <netinet/in_systm.h>
134 #include <netinet/ip.h>
135 #include <netinet/in_pcb.h>
136 #include <netinet/in_var.h>
137 #include <netinet/ip_var.h>
138 #include <netinet/ip_icmp.h>
139 /* just for gif_ttl */
140 #include <netinet/in_gif.h>
141 #include "gif.h"
142 #include <net/if_gre.h>
143 #include "gre.h"
144
145 #ifdef MROUTING
146 #include <netinet/ip_mroute.h>
147 #endif
148
149 #ifdef IPSEC
150 #include <netinet6/ipsec.h>
151 #include <netkey/key.h>
152 #endif
153
154 #ifndef IPFORWARDING
155 #ifdef GATEWAY
156 #define IPFORWARDING 1 /* forward IP packets not for us */
157 #else /* GATEWAY */
158 #define IPFORWARDING 0 /* don't forward IP packets not for us */
159 #endif /* GATEWAY */
160 #endif /* IPFORWARDING */
161 #ifndef IPSENDREDIRECTS
162 #define IPSENDREDIRECTS 1
163 #endif
164 #ifndef IPFORWSRCRT
165 #define IPFORWSRCRT 1 /* forward source-routed packets */
166 #endif
167 #ifndef IPALLOWSRCRT
168 #define IPALLOWSRCRT 1 /* allow source-routed packets */
169 #endif
170 #ifndef IPMTUDISC
171 #define IPMTUDISC 1
172 #endif
173 #ifndef IPMTUDISCTIMEOUT
174 #define IPMTUDISCTIMEOUT (10 * 60) /* as per RFC 1191 */
175 #endif
176
177 /*
178 * Note: DIRECTED_BROADCAST is handled this way so that previous
179 * configuration using this option will Just Work.
180 */
181 #ifndef IPDIRECTEDBCAST
182 #ifdef DIRECTED_BROADCAST
183 #define IPDIRECTEDBCAST 1
184 #else
185 #define IPDIRECTEDBCAST 0
186 #endif /* DIRECTED_BROADCAST */
187 #endif /* IPDIRECTEDBCAST */
188 int ipforwarding = IPFORWARDING;
189 int ipsendredirects = IPSENDREDIRECTS;
190 int ip_defttl = IPDEFTTL;
191 int ip_forwsrcrt = IPFORWSRCRT;
192 int ip_directedbcast = IPDIRECTEDBCAST;
193 int ip_allowsrcrt = IPALLOWSRCRT;
194 int ip_mtudisc = IPMTUDISC;
195 int ip_mtudisc_timeout = IPMTUDISCTIMEOUT;
196 #ifdef DIAGNOSTIC
197 int ipprintfs = 0;
198 #endif
199 /*
200 * XXX - Setting ip_checkinterface mostly implements the receive side of
201 * the Strong ES model described in RFC 1122, but since the routing table
202 * and transmit implementation do not implement the Strong ES model,
203 * setting this to 1 results in an odd hybrid.
204 *
205 * XXX - ip_checkinterface currently must be disabled if you use ipnat
206 * to translate the destination address to another local interface.
207 *
208 * XXX - ip_checkinterface must be disabled if you add IP aliases
209 * to the loopback interface instead of the interface where the
210 * packets for those addresses are received.
211 */
212 int ip_checkinterface = 0;
213
214
215 struct rttimer_queue *ip_mtudisc_timeout_q = NULL;
216
217 extern struct domain inetdomain;
218 int ipqmaxlen = IFQ_MAXLEN;
219 u_long in_ifaddrhash; /* size of hash table - 1 */
220 int in_ifaddrentries; /* total number of addrs */
221 struct in_ifaddrhead in_ifaddr;
222 struct in_ifaddrhashhead *in_ifaddrhashtbl;
223 u_long in_multihash; /* size of hash table - 1 */
224 int in_multientries; /* total number of addrs */
225 struct in_multihead in_multi;
226 struct in_multihashhead *in_multihashtbl;
227 struct ifqueue ipintrq;
228 struct ipstat ipstat;
229 u_int16_t ip_id;
230
231 #ifdef PFIL_HOOKS
232 struct pfil_head inet_pfil_hook;
233 #endif
234
235 struct ipqhead ipq;
236 int ipq_locked;
237 int ip_nfragpackets = 0;
238 int ip_maxfragpackets = 200;
239
240 static __inline int ipq_lock_try __P((void));
241 static __inline void ipq_unlock __P((void));
242
243 static __inline int
244 ipq_lock_try()
245 {
246 int s;
247
248 /*
249 * Use splvm() -- we're blocking things that would cause
250 * mbuf allocation.
251 */
252 s = splvm();
253 if (ipq_locked) {
254 splx(s);
255 return (0);
256 }
257 ipq_locked = 1;
258 splx(s);
259 return (1);
260 }
261
262 static __inline void
263 ipq_unlock()
264 {
265 int s;
266
267 s = splvm();
268 ipq_locked = 0;
269 splx(s);
270 }
271
272 #ifdef DIAGNOSTIC
273 #define IPQ_LOCK() \
274 do { \
275 if (ipq_lock_try() == 0) { \
276 printf("%s:%d: ipq already locked\n", __FILE__, __LINE__); \
277 panic("ipq_lock"); \
278 } \
279 } while (/*CONSTCOND*/ 0)
280 #define IPQ_LOCK_CHECK() \
281 do { \
282 if (ipq_locked == 0) { \
283 printf("%s:%d: ipq lock not held\n", __FILE__, __LINE__); \
284 panic("ipq lock check"); \
285 } \
286 } while (/*CONSTCOND*/ 0)
287 #else
288 #define IPQ_LOCK() (void) ipq_lock_try()
289 #define IPQ_LOCK_CHECK() /* nothing */
290 #endif
291
292 #define IPQ_UNLOCK() ipq_unlock()
293
294 struct pool inmulti_pool;
295 struct pool ipqent_pool;
296
297 #ifdef INET_CSUM_COUNTERS
298 #include <sys/device.h>
299
300 struct evcnt ip_hwcsum_bad = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
301 NULL, "inet", "hwcsum bad");
302 struct evcnt ip_hwcsum_ok = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
303 NULL, "inet", "hwcsum ok");
304 struct evcnt ip_swcsum = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
305 NULL, "inet", "swcsum");
306
307 #define INET_CSUM_COUNTER_INCR(ev) (ev)->ev_count++
308
309 #else
310
311 #define INET_CSUM_COUNTER_INCR(ev) /* nothing */
312
313 #endif /* INET_CSUM_COUNTERS */
314
315 /*
316 * We need to save the IP options in case a protocol wants to respond
317 * to an incoming packet over the same route if the packet got here
318 * using IP source routing. This allows connection establishment and
319 * maintenance when the remote end is on a network that is not known
320 * to us.
321 */
322 int ip_nhops = 0;
323 static struct ip_srcrt {
324 struct in_addr dst; /* final destination */
325 char nop; /* one NOP to align */
326 char srcopt[IPOPT_OFFSET + 1]; /* OPTVAL, OLEN and OFFSET */
327 struct in_addr route[MAX_IPOPTLEN/sizeof(struct in_addr)];
328 } ip_srcrt;
329
330 static void save_rte __P((u_char *, struct in_addr));
331
332 #ifdef MBUFTRACE
333 struct mowner ip_rx_mowner = { "internet", "rx" };
334 struct mowner ip_tx_mowner = { "internet", "tx" };
335 #endif
336
337 /*
338 * IP initialization: fill in IP protocol switch table.
339 * All protocols not implemented in kernel go to raw IP protocol handler.
340 */
341 void
342 ip_init()
343 {
344 struct protosw *pr;
345 int i;
346
347 pool_init(&inmulti_pool, sizeof(struct in_multi), 0, 0, 0, "inmltpl",
348 NULL);
349 pool_init(&ipqent_pool, sizeof(struct ipqent), 0, 0, 0, "ipqepl",
350 NULL);
351
352 pr = pffindproto(PF_INET, IPPROTO_RAW, SOCK_RAW);
353 if (pr == 0)
354 panic("ip_init");
355 for (i = 0; i < IPPROTO_MAX; i++)
356 ip_protox[i] = pr - inetsw;
357 for (pr = inetdomain.dom_protosw;
358 pr < inetdomain.dom_protoswNPROTOSW; pr++)
359 if (pr->pr_domain->dom_family == PF_INET &&
360 pr->pr_protocol && pr->pr_protocol != IPPROTO_RAW)
361 ip_protox[pr->pr_protocol] = pr - inetsw;
362 LIST_INIT(&ipq);
363 ip_id = time.tv_sec & 0xffff;
364 ipintrq.ifq_maxlen = ipqmaxlen;
365 TAILQ_INIT(&in_ifaddr);
366 in_ifaddrhashtbl = hashinit(IN_IFADDR_HASH_SIZE, HASH_LIST, M_IFADDR,
367 M_WAITOK, &in_ifaddrhash);
368 in_multihashtbl = hashinit(IN_IFADDR_HASH_SIZE, HASH_LIST, M_IPMADDR,
369 M_WAITOK, &in_multihash);
370 ip_mtudisc_timeout_q = rt_timer_queue_create(ip_mtudisc_timeout);
371 #ifdef GATEWAY
372 ipflow_init();
373 #endif
374
375 #ifdef PFIL_HOOKS
376 /* Register our Packet Filter hook. */
377 inet_pfil_hook.ph_type = PFIL_TYPE_AF;
378 inet_pfil_hook.ph_af = AF_INET;
379 i = pfil_head_register(&inet_pfil_hook);
380 if (i != 0)
381 printf("ip_init: WARNING: unable to register pfil hook, "
382 "error %d\n", i);
383 #endif /* PFIL_HOOKS */
384
385 #ifdef INET_CSUM_COUNTERS
386 evcnt_attach_static(&ip_hwcsum_bad);
387 evcnt_attach_static(&ip_hwcsum_ok);
388 evcnt_attach_static(&ip_swcsum);
389 #endif /* INET_CSUM_COUNTERS */
390
391 #ifdef MBUFTRACE
392 MOWNER_ATTACH(&ip_tx_mowner);
393 MOWNER_ATTACH(&ip_rx_mowner);
394 #endif /* MBUFTRACE */
395 }
396
397 struct sockaddr_in ipaddr = { sizeof(ipaddr), AF_INET };
398 struct route ipforward_rt;
399
400 /*
401 * IP software interrupt routine
402 */
403 void
404 ipintr()
405 {
406 int s;
407 struct mbuf *m;
408
409 while (1) {
410 s = splnet();
411 IF_DEQUEUE(&ipintrq, m);
412 splx(s);
413 if (m == 0)
414 return;
415 MCLAIM(m, &ip_rx_mowner);
416 ip_input(m);
417 }
418 }
419
420 /*
421 * Ip input routine. Checksum and byte swap header. If fragmented
422 * try to reassemble. Process options. Pass to next level.
423 */
424 void
425 ip_input(struct mbuf *m)
426 {
427 struct ip *ip = NULL;
428 struct ipq *fp;
429 struct in_ifaddr *ia;
430 struct ifaddr *ifa;
431 struct ipqent *ipqe;
432 int hlen = 0, mff, len;
433 int downmatch;
434 int checkif;
435
436 MCLAIM(m, &ip_rx_mowner);
437 #ifdef DIAGNOSTIC
438 if ((m->m_flags & M_PKTHDR) == 0)
439 panic("ipintr no HDR");
440 #endif
441 #ifdef IPSEC
442 /*
443 * should the inner packet be considered authentic?
444 * see comment in ah4_input().
445 */
446 if (m) {
447 m->m_flags &= ~M_AUTHIPHDR;
448 m->m_flags &= ~M_AUTHIPDGM;
449 }
450 #endif
451
452 /*
453 * If no IP addresses have been set yet but the interfaces
454 * are receiving, can't do anything with incoming packets yet.
455 */
456 if (TAILQ_FIRST(&in_ifaddr) == 0)
457 goto bad;
458 ipstat.ips_total++;
459 /*
460 * If the IP header is not aligned, slurp it up into a new
461 * mbuf with space for link headers, in the event we forward
462 * it. Otherwise, if it is aligned, make sure the entire
463 * base IP header is in the first mbuf of the chain.
464 */
465 if (IP_HDR_ALIGNED_P(mtod(m, caddr_t)) == 0) {
466 if ((m = m_copyup(m, sizeof(struct ip),
467 (max_linkhdr + 3) & ~3)) == NULL) {
468 /* XXXJRT new stat, please */
469 ipstat.ips_toosmall++;
470 return;
471 }
472 } else if (__predict_false(m->m_len < sizeof (struct ip))) {
473 if ((m = m_pullup(m, sizeof (struct ip))) == NULL) {
474 ipstat.ips_toosmall++;
475 return;
476 }
477 }
478 ip = mtod(m, struct ip *);
479 if (ip->ip_v != IPVERSION) {
480 ipstat.ips_badvers++;
481 goto bad;
482 }
483 hlen = ip->ip_hl << 2;
484 if (hlen < sizeof(struct ip)) { /* minimum header length */
485 ipstat.ips_badhlen++;
486 goto bad;
487 }
488 if (hlen > m->m_len) {
489 if ((m = m_pullup(m, hlen)) == 0) {
490 ipstat.ips_badhlen++;
491 return;
492 }
493 ip = mtod(m, struct ip *);
494 }
495
496 /*
497 * RFC1122: packets with a multicast source address are
498 * not allowed.
499 */
500 if (IN_MULTICAST(ip->ip_src.s_addr)) {
501 ipstat.ips_badaddr++;
502 goto bad;
503 }
504
505 /* 127/8 must not appear on wire - RFC1122 */
506 if ((ntohl(ip->ip_dst.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET ||
507 (ntohl(ip->ip_src.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET) {
508 if ((m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) == 0) {
509 ipstat.ips_badaddr++;
510 goto bad;
511 }
512 }
513
514 switch (m->m_pkthdr.csum_flags &
515 ((m->m_pkthdr.rcvif->if_csum_flags_rx & M_CSUM_IPv4) |
516 M_CSUM_IPv4_BAD)) {
517 case M_CSUM_IPv4|M_CSUM_IPv4_BAD:
518 INET_CSUM_COUNTER_INCR(&ip_hwcsum_bad);
519 goto badcsum;
520
521 case M_CSUM_IPv4:
522 /* Checksum was okay. */
523 INET_CSUM_COUNTER_INCR(&ip_hwcsum_ok);
524 break;
525
526 default:
527 /* Must compute it ourselves. */
528 INET_CSUM_COUNTER_INCR(&ip_swcsum);
529 if (in_cksum(m, hlen) != 0)
530 goto bad;
531 break;
532 }
533
534 /* Retrieve the packet length. */
535 len = ntohs(ip->ip_len);
536
537 /*
538 * Check for additional length bogosity
539 */
540 if (len < hlen) {
541 ipstat.ips_badlen++;
542 goto bad;
543 }
544
545 /*
546 * Check that the amount of data in the buffers
547 * is as at least much as the IP header would have us expect.
548 * Trim mbufs if longer than we expect.
549 * Drop packet if shorter than we expect.
550 */
551 if (m->m_pkthdr.len < len) {
552 ipstat.ips_tooshort++;
553 goto bad;
554 }
555 if (m->m_pkthdr.len > len) {
556 if (m->m_len == m->m_pkthdr.len) {
557 m->m_len = len;
558 m->m_pkthdr.len = len;
559 } else
560 m_adj(m, len - m->m_pkthdr.len);
561 }
562
563 #ifdef IPSEC
564 /* ipflow (IP fast forwarding) is not compatible with IPsec. */
565 m->m_flags &= ~M_CANFASTFWD;
566 #else
567 /*
568 * Assume that we can create a fast-forward IP flow entry
569 * based on this packet.
570 */
571 m->m_flags |= M_CANFASTFWD;
572 #endif
573
574 #ifdef PFIL_HOOKS
575 /*
576 * Run through list of hooks for input packets. If there are any
577 * filters which require that additional packets in the flow are
578 * not fast-forwarded, they must clear the M_CANFASTFWD flag.
579 * Note that filters must _never_ set this flag, as another filter
580 * in the list may have previously cleared it.
581 */
582 /*
583 * let ipfilter look at packet on the wire,
584 * not the decapsulated packet.
585 */
586 #ifdef IPSEC
587 if (!ipsec_getnhist(m))
588 #else
589 if (1)
590 #endif
591 {
592 if (pfil_run_hooks(&inet_pfil_hook, &m, m->m_pkthdr.rcvif,
593 PFIL_IN) != 0)
594 return;
595 if (m == NULL)
596 return;
597 ip = mtod(m, struct ip *);
598 hlen = ip->ip_hl << 2;
599 }
600 #endif /* PFIL_HOOKS */
601
602 #ifdef ALTQ
603 /* XXX Temporary until ALTQ is changed to use a pfil hook */
604 if (altq_input != NULL && (*altq_input)(m, AF_INET) == 0) {
605 /* packet dropped by traffic conditioner */
606 return;
607 }
608 #endif
609
610 /*
611 * Process options and, if not destined for us,
612 * ship it on. ip_dooptions returns 1 when an
613 * error was detected (causing an icmp message
614 * to be sent and the original packet to be freed).
615 */
616 ip_nhops = 0; /* for source routed packets */
617 if (hlen > sizeof (struct ip) && ip_dooptions(m))
618 return;
619
620 /*
621 * Enable a consistency check between the destination address
622 * and the arrival interface for a unicast packet (the RFC 1122
623 * strong ES model) if IP forwarding is disabled and the packet
624 * is not locally generated.
625 *
626 * XXX - Checking also should be disabled if the destination
627 * address is ipnat'ed to a different interface.
628 *
629 * XXX - Checking is incompatible with IP aliases added
630 * to the loopback interface instead of the interface where
631 * the packets are received.
632 *
633 * XXX - We need to add a per ifaddr flag for this so that
634 * we get finer grain control.
635 */
636 checkif = ip_checkinterface && (ipforwarding == 0) &&
637 (m->m_pkthdr.rcvif != NULL) &&
638 ((m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) == 0);
639
640 /*
641 * Check our list of addresses, to see if the packet is for us.
642 *
643 * Traditional 4.4BSD did not consult IFF_UP at all.
644 * The behavior here is to treat addresses on !IFF_UP interface
645 * as not mine.
646 */
647 downmatch = 0;
648 LIST_FOREACH(ia, &IN_IFADDR_HASH(ip->ip_dst.s_addr), ia_hash) {
649 if (in_hosteq(ia->ia_addr.sin_addr, ip->ip_dst)) {
650 if (checkif && ia->ia_ifp != m->m_pkthdr.rcvif)
651 continue;
652 if ((ia->ia_ifp->if_flags & IFF_UP) != 0)
653 break;
654 else
655 downmatch++;
656 }
657 }
658 if (ia != NULL)
659 goto ours;
660 if (m->m_pkthdr.rcvif->if_flags & IFF_BROADCAST) {
661 TAILQ_FOREACH(ifa, &m->m_pkthdr.rcvif->if_addrlist, ifa_list) {
662 if (ifa->ifa_addr->sa_family != AF_INET)
663 continue;
664 ia = ifatoia(ifa);
665 if (in_hosteq(ip->ip_dst, ia->ia_broadaddr.sin_addr) ||
666 in_hosteq(ip->ip_dst, ia->ia_netbroadcast) ||
667 /*
668 * Look for all-0's host part (old broadcast addr),
669 * either for subnet or net.
670 */
671 ip->ip_dst.s_addr == ia->ia_subnet ||
672 ip->ip_dst.s_addr == ia->ia_net)
673 goto ours;
674 /*
675 * An interface with IP address zero accepts
676 * all packets that arrive on that interface.
677 */
678 if (in_nullhost(ia->ia_addr.sin_addr))
679 goto ours;
680 }
681 }
682 if (IN_MULTICAST(ip->ip_dst.s_addr)) {
683 struct in_multi *inm;
684 #ifdef MROUTING
685 extern struct socket *ip_mrouter;
686
687 if (M_READONLY(m)) {
688 if ((m = m_pullup(m, hlen)) == 0) {
689 ipstat.ips_toosmall++;
690 return;
691 }
692 ip = mtod(m, struct ip *);
693 }
694
695 if (ip_mrouter) {
696 /*
697 * If we are acting as a multicast router, all
698 * incoming multicast packets are passed to the
699 * kernel-level multicast forwarding function.
700 * The packet is returned (relatively) intact; if
701 * ip_mforward() returns a non-zero value, the packet
702 * must be discarded, else it may be accepted below.
703 *
704 * (The IP ident field is put in the same byte order
705 * as expected when ip_mforward() is called from
706 * ip_output().)
707 */
708 if (ip_mforward(m, m->m_pkthdr.rcvif) != 0) {
709 ipstat.ips_cantforward++;
710 m_freem(m);
711 return;
712 }
713
714 /*
715 * The process-level routing demon needs to receive
716 * all multicast IGMP packets, whether or not this
717 * host belongs to their destination groups.
718 */
719 if (ip->ip_p == IPPROTO_IGMP)
720 goto ours;
721 ipstat.ips_forward++;
722 }
723 #endif
724 /*
725 * See if we belong to the destination multicast group on the
726 * arrival interface.
727 */
728 IN_LOOKUP_MULTI(ip->ip_dst, m->m_pkthdr.rcvif, inm);
729 if (inm == NULL) {
730 ipstat.ips_cantforward++;
731 m_freem(m);
732 return;
733 }
734 goto ours;
735 }
736 if (ip->ip_dst.s_addr == INADDR_BROADCAST ||
737 in_nullhost(ip->ip_dst))
738 goto ours;
739
740 /*
741 * Not for us; forward if possible and desirable.
742 */
743 if (ipforwarding == 0) {
744 ipstat.ips_cantforward++;
745 m_freem(m);
746 } else {
747 /*
748 * If ip_dst matched any of my address on !IFF_UP interface,
749 * and there's no IFF_UP interface that matches ip_dst,
750 * send icmp unreach. Forwarding it will result in in-kernel
751 * forwarding loop till TTL goes to 0.
752 */
753 if (downmatch) {
754 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_HOST, 0, 0);
755 ipstat.ips_cantforward++;
756 return;
757 }
758 #ifdef IPSEC
759 if (ipsec4_in_reject(m, NULL)) {
760 ipsecstat.in_polvio++;
761 goto bad;
762 }
763 #endif
764
765 ip_forward(m, 0);
766 }
767 return;
768
769 ours:
770 /*
771 * If offset or IP_MF are set, must reassemble.
772 * Otherwise, nothing need be done.
773 * (We could look in the reassembly queue to see
774 * if the packet was previously fragmented,
775 * but it's not worth the time; just let them time out.)
776 */
777 if (ip->ip_off & ~htons(IP_DF|IP_RF)) {
778 if (M_READONLY(m)) {
779 if ((m = m_pullup(m, hlen)) == NULL) {
780 ipstat.ips_toosmall++;
781 goto bad;
782 }
783 ip = mtod(m, struct ip *);
784 }
785
786 /*
787 * Look for queue of fragments
788 * of this datagram.
789 */
790 IPQ_LOCK();
791 LIST_FOREACH(fp, &ipq, ipq_q)
792 if (ip->ip_id == fp->ipq_id &&
793 in_hosteq(ip->ip_src, fp->ipq_src) &&
794 in_hosteq(ip->ip_dst, fp->ipq_dst) &&
795 ip->ip_p == fp->ipq_p)
796 goto found;
797 fp = 0;
798 found:
799
800 /*
801 * Adjust ip_len to not reflect header,
802 * set ipqe_mff if more fragments are expected,
803 * convert offset of this to bytes.
804 */
805 ip->ip_len = htons(ntohs(ip->ip_len) - hlen);
806 mff = (ip->ip_off & htons(IP_MF)) != 0;
807 if (mff) {
808 /*
809 * Make sure that fragments have a data length
810 * that's a non-zero multiple of 8 bytes.
811 */
812 if (ntohs(ip->ip_len) == 0 ||
813 (ntohs(ip->ip_len) & 0x7) != 0) {
814 ipstat.ips_badfrags++;
815 IPQ_UNLOCK();
816 goto bad;
817 }
818 }
819 ip->ip_off = htons((ntohs(ip->ip_off) & IP_OFFMASK) << 3);
820
821 /*
822 * If datagram marked as having more fragments
823 * or if this is not the first fragment,
824 * attempt reassembly; if it succeeds, proceed.
825 */
826 if (mff || ip->ip_off != htons(0)) {
827 ipstat.ips_fragments++;
828 ipqe = pool_get(&ipqent_pool, PR_NOWAIT);
829 if (ipqe == NULL) {
830 ipstat.ips_rcvmemdrop++;
831 IPQ_UNLOCK();
832 goto bad;
833 }
834 ipqe->ipqe_mff = mff;
835 ipqe->ipqe_m = m;
836 ipqe->ipqe_ip = ip;
837 m = ip_reass(ipqe, fp);
838 if (m == 0) {
839 IPQ_UNLOCK();
840 return;
841 }
842 ipstat.ips_reassembled++;
843 ip = mtod(m, struct ip *);
844 hlen = ip->ip_hl << 2;
845 ip->ip_len = htons(ntohs(ip->ip_len) + hlen);
846 } else
847 if (fp)
848 ip_freef(fp);
849 IPQ_UNLOCK();
850 }
851
852 #ifdef IPSEC
853 /*
854 * enforce IPsec policy checking if we are seeing last header.
855 * note that we do not visit this with protocols with pcb layer
856 * code - like udp/tcp/raw ip.
857 */
858 if ((inetsw[ip_protox[ip->ip_p]].pr_flags & PR_LASTHDR) != 0 &&
859 ipsec4_in_reject(m, NULL)) {
860 ipsecstat.in_polvio++;
861 goto bad;
862 }
863 #endif
864
865 /*
866 * Switch out to protocol's input routine.
867 */
868 #if IFA_STATS
869 if (ia && ip)
870 ia->ia_ifa.ifa_data.ifad_inbytes += ntohs(ip->ip_len);
871 #endif
872 ipstat.ips_delivered++;
873 {
874 int off = hlen, nh = ip->ip_p;
875
876 (*inetsw[ip_protox[nh]].pr_input)(m, off, nh);
877 return;
878 }
879 bad:
880 m_freem(m);
881 return;
882
883 badcsum:
884 ipstat.ips_badsum++;
885 m_freem(m);
886 }
887
888 /*
889 * Take incoming datagram fragment and try to
890 * reassemble it into whole datagram. If a chain for
891 * reassembly of this datagram already exists, then it
892 * is given as fp; otherwise have to make a chain.
893 */
894 struct mbuf *
895 ip_reass(ipqe, fp)
896 struct ipqent *ipqe;
897 struct ipq *fp;
898 {
899 struct mbuf *m = ipqe->ipqe_m;
900 struct ipqent *nq, *p, *q;
901 struct ip *ip;
902 struct mbuf *t;
903 int hlen = ipqe->ipqe_ip->ip_hl << 2;
904 int i, next;
905
906 IPQ_LOCK_CHECK();
907
908 /*
909 * Presence of header sizes in mbufs
910 * would confuse code below.
911 */
912 m->m_data += hlen;
913 m->m_len -= hlen;
914
915 /*
916 * If first fragment to arrive, create a reassembly queue.
917 */
918 if (fp == 0) {
919 /*
920 * Enforce upper bound on number of fragmented packets
921 * for which we attempt reassembly;
922 * If maxfrag is 0, never accept fragments.
923 * If maxfrag is -1, accept all fragments without limitation.
924 */
925 if (ip_maxfragpackets < 0)
926 ;
927 else if (ip_nfragpackets >= ip_maxfragpackets)
928 goto dropfrag;
929 ip_nfragpackets++;
930 MALLOC(fp, struct ipq *, sizeof (struct ipq),
931 M_FTABLE, M_NOWAIT);
932 if (fp == NULL)
933 goto dropfrag;
934 LIST_INSERT_HEAD(&ipq, fp, ipq_q);
935 fp->ipq_ttl = IPFRAGTTL;
936 fp->ipq_p = ipqe->ipqe_ip->ip_p;
937 fp->ipq_id = ipqe->ipqe_ip->ip_id;
938 TAILQ_INIT(&fp->ipq_fragq);
939 fp->ipq_src = ipqe->ipqe_ip->ip_src;
940 fp->ipq_dst = ipqe->ipqe_ip->ip_dst;
941 p = NULL;
942 goto insert;
943 }
944
945 /*
946 * Find a segment which begins after this one does.
947 */
948 for (p = NULL, q = TAILQ_FIRST(&fp->ipq_fragq); q != NULL;
949 p = q, q = TAILQ_NEXT(q, ipqe_q))
950 if (ntohs(q->ipqe_ip->ip_off) > ntohs(ipqe->ipqe_ip->ip_off))
951 break;
952
953 /*
954 * If there is a preceding segment, it may provide some of
955 * our data already. If so, drop the data from the incoming
956 * segment. If it provides all of our data, drop us.
957 */
958 if (p != NULL) {
959 i = ntohs(p->ipqe_ip->ip_off) + ntohs(p->ipqe_ip->ip_len) -
960 ntohs(ipqe->ipqe_ip->ip_off);
961 if (i > 0) {
962 if (i >= ntohs(ipqe->ipqe_ip->ip_len))
963 goto dropfrag;
964 m_adj(ipqe->ipqe_m, i);
965 ipqe->ipqe_ip->ip_off =
966 htons(ntohs(ipqe->ipqe_ip->ip_off) + i);
967 ipqe->ipqe_ip->ip_len =
968 htons(ntohs(ipqe->ipqe_ip->ip_len) - i);
969 }
970 }
971
972 /*
973 * While we overlap succeeding segments trim them or,
974 * if they are completely covered, dequeue them.
975 */
976 for (; q != NULL &&
977 ntohs(ipqe->ipqe_ip->ip_off) + ntohs(ipqe->ipqe_ip->ip_len) >
978 ntohs(q->ipqe_ip->ip_off); q = nq) {
979 i = (ntohs(ipqe->ipqe_ip->ip_off) +
980 ntohs(ipqe->ipqe_ip->ip_len)) - ntohs(q->ipqe_ip->ip_off);
981 if (i < ntohs(q->ipqe_ip->ip_len)) {
982 q->ipqe_ip->ip_len =
983 htons(ntohs(q->ipqe_ip->ip_len) - i);
984 q->ipqe_ip->ip_off =
985 htons(ntohs(q->ipqe_ip->ip_off) + i);
986 m_adj(q->ipqe_m, i);
987 break;
988 }
989 nq = TAILQ_NEXT(q, ipqe_q);
990 m_freem(q->ipqe_m);
991 TAILQ_REMOVE(&fp->ipq_fragq, q, ipqe_q);
992 pool_put(&ipqent_pool, q);
993 }
994
995 insert:
996 /*
997 * Stick new segment in its place;
998 * check for complete reassembly.
999 */
1000 if (p == NULL) {
1001 TAILQ_INSERT_HEAD(&fp->ipq_fragq, ipqe, ipqe_q);
1002 } else {
1003 TAILQ_INSERT_AFTER(&fp->ipq_fragq, p, ipqe, ipqe_q);
1004 }
1005 next = 0;
1006 for (p = NULL, q = TAILQ_FIRST(&fp->ipq_fragq); q != NULL;
1007 p = q, q = TAILQ_NEXT(q, ipqe_q)) {
1008 if (ntohs(q->ipqe_ip->ip_off) != next)
1009 return (0);
1010 next += ntohs(q->ipqe_ip->ip_len);
1011 }
1012 if (p->ipqe_mff)
1013 return (0);
1014
1015 /*
1016 * Reassembly is complete. Check for a bogus message size and
1017 * concatenate fragments.
1018 */
1019 q = TAILQ_FIRST(&fp->ipq_fragq);
1020 ip = q->ipqe_ip;
1021 if ((next + (ip->ip_hl << 2)) > IP_MAXPACKET) {
1022 ipstat.ips_toolong++;
1023 ip_freef(fp);
1024 return (0);
1025 }
1026 m = q->ipqe_m;
1027 t = m->m_next;
1028 m->m_next = 0;
1029 m_cat(m, t);
1030 nq = TAILQ_NEXT(q, ipqe_q);
1031 pool_put(&ipqent_pool, q);
1032 for (q = nq; q != NULL; q = nq) {
1033 t = q->ipqe_m;
1034 nq = TAILQ_NEXT(q, ipqe_q);
1035 pool_put(&ipqent_pool, q);
1036 m_cat(m, t);
1037 }
1038
1039 /*
1040 * Create header for new ip packet by
1041 * modifying header of first packet;
1042 * dequeue and discard fragment reassembly header.
1043 * Make header visible.
1044 */
1045 ip->ip_len = htons(next);
1046 ip->ip_src = fp->ipq_src;
1047 ip->ip_dst = fp->ipq_dst;
1048 LIST_REMOVE(fp, ipq_q);
1049 FREE(fp, M_FTABLE);
1050 ip_nfragpackets--;
1051 m->m_len += (ip->ip_hl << 2);
1052 m->m_data -= (ip->ip_hl << 2);
1053 /* some debugging cruft by sklower, below, will go away soon */
1054 if (m->m_flags & M_PKTHDR) { /* XXX this should be done elsewhere */
1055 int plen = 0;
1056 for (t = m; t; t = t->m_next)
1057 plen += t->m_len;
1058 m->m_pkthdr.len = plen;
1059 }
1060 return (m);
1061
1062 dropfrag:
1063 ipstat.ips_fragdropped++;
1064 m_freem(m);
1065 pool_put(&ipqent_pool, ipqe);
1066 return (0);
1067 }
1068
1069 /*
1070 * Free a fragment reassembly header and all
1071 * associated datagrams.
1072 */
1073 void
1074 ip_freef(fp)
1075 struct ipq *fp;
1076 {
1077 struct ipqent *q, *p;
1078
1079 IPQ_LOCK_CHECK();
1080
1081 for (q = TAILQ_FIRST(&fp->ipq_fragq); q != NULL; q = p) {
1082 p = TAILQ_NEXT(q, ipqe_q);
1083 m_freem(q->ipqe_m);
1084 TAILQ_REMOVE(&fp->ipq_fragq, q, ipqe_q);
1085 pool_put(&ipqent_pool, q);
1086 }
1087 LIST_REMOVE(fp, ipq_q);
1088 FREE(fp, M_FTABLE);
1089 ip_nfragpackets--;
1090 }
1091
1092 /*
1093 * IP timer processing;
1094 * if a timer expires on a reassembly
1095 * queue, discard it.
1096 */
1097 void
1098 ip_slowtimo()
1099 {
1100 struct ipq *fp, *nfp;
1101 int s = splsoftnet();
1102
1103 IPQ_LOCK();
1104 for (fp = LIST_FIRST(&ipq); fp != NULL; fp = nfp) {
1105 nfp = LIST_NEXT(fp, ipq_q);
1106 if (--fp->ipq_ttl == 0) {
1107 ipstat.ips_fragtimeout++;
1108 ip_freef(fp);
1109 }
1110 }
1111 /*
1112 * If we are over the maximum number of fragments
1113 * (due to the limit being lowered), drain off
1114 * enough to get down to the new limit.
1115 */
1116 if (ip_maxfragpackets < 0)
1117 ;
1118 else {
1119 while (ip_nfragpackets > ip_maxfragpackets && LIST_FIRST(&ipq))
1120 ip_freef(LIST_FIRST(&ipq));
1121 }
1122 IPQ_UNLOCK();
1123 #ifdef GATEWAY
1124 ipflow_slowtimo();
1125 #endif
1126 splx(s);
1127 }
1128
1129 /*
1130 * Drain off all datagram fragments.
1131 */
1132 void
1133 ip_drain()
1134 {
1135
1136 /*
1137 * We may be called from a device's interrupt context. If
1138 * the ipq is already busy, just bail out now.
1139 */
1140 if (ipq_lock_try() == 0)
1141 return;
1142
1143 while (LIST_FIRST(&ipq) != NULL) {
1144 ipstat.ips_fragdropped++;
1145 ip_freef(LIST_FIRST(&ipq));
1146 }
1147
1148 IPQ_UNLOCK();
1149 }
1150
1151 /*
1152 * Do option processing on a datagram,
1153 * possibly discarding it if bad options are encountered,
1154 * or forwarding it if source-routed.
1155 * Returns 1 if packet has been forwarded/freed,
1156 * 0 if the packet should be processed further.
1157 */
1158 int
1159 ip_dooptions(m)
1160 struct mbuf *m;
1161 {
1162 struct ip *ip = mtod(m, struct ip *);
1163 u_char *cp, *cp0;
1164 struct ip_timestamp *ipt;
1165 struct in_ifaddr *ia;
1166 int opt, optlen, cnt, off, code, type = ICMP_PARAMPROB, forward = 0;
1167 struct in_addr dst;
1168 n_time ntime;
1169
1170 dst = ip->ip_dst;
1171 cp = (u_char *)(ip + 1);
1172 cnt = (ip->ip_hl << 2) - sizeof (struct ip);
1173 for (; cnt > 0; cnt -= optlen, cp += optlen) {
1174 opt = cp[IPOPT_OPTVAL];
1175 if (opt == IPOPT_EOL)
1176 break;
1177 if (opt == IPOPT_NOP)
1178 optlen = 1;
1179 else {
1180 if (cnt < IPOPT_OLEN + sizeof(*cp)) {
1181 code = &cp[IPOPT_OLEN] - (u_char *)ip;
1182 goto bad;
1183 }
1184 optlen = cp[IPOPT_OLEN];
1185 if (optlen < IPOPT_OLEN + sizeof(*cp) || optlen > cnt) {
1186 code = &cp[IPOPT_OLEN] - (u_char *)ip;
1187 goto bad;
1188 }
1189 }
1190 switch (opt) {
1191
1192 default:
1193 break;
1194
1195 /*
1196 * Source routing with record.
1197 * Find interface with current destination address.
1198 * If none on this machine then drop if strictly routed,
1199 * or do nothing if loosely routed.
1200 * Record interface address and bring up next address
1201 * component. If strictly routed make sure next
1202 * address is on directly accessible net.
1203 */
1204 case IPOPT_LSRR:
1205 case IPOPT_SSRR:
1206 if (ip_allowsrcrt == 0) {
1207 type = ICMP_UNREACH;
1208 code = ICMP_UNREACH_NET_PROHIB;
1209 goto bad;
1210 }
1211 if (optlen < IPOPT_OFFSET + sizeof(*cp)) {
1212 code = &cp[IPOPT_OLEN] - (u_char *)ip;
1213 goto bad;
1214 }
1215 if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) {
1216 code = &cp[IPOPT_OFFSET] - (u_char *)ip;
1217 goto bad;
1218 }
1219 ipaddr.sin_addr = ip->ip_dst;
1220 ia = ifatoia(ifa_ifwithaddr(sintosa(&ipaddr)));
1221 if (ia == 0) {
1222 if (opt == IPOPT_SSRR) {
1223 type = ICMP_UNREACH;
1224 code = ICMP_UNREACH_SRCFAIL;
1225 goto bad;
1226 }
1227 /*
1228 * Loose routing, and not at next destination
1229 * yet; nothing to do except forward.
1230 */
1231 break;
1232 }
1233 off--; /* 0 origin */
1234 if ((off + sizeof(struct in_addr)) > optlen) {
1235 /*
1236 * End of source route. Should be for us.
1237 */
1238 save_rte(cp, ip->ip_src);
1239 break;
1240 }
1241 /*
1242 * locate outgoing interface
1243 */
1244 bcopy((caddr_t)(cp + off), (caddr_t)&ipaddr.sin_addr,
1245 sizeof(ipaddr.sin_addr));
1246 if (opt == IPOPT_SSRR)
1247 ia = ifatoia(ifa_ifwithaddr(sintosa(&ipaddr)));
1248 else
1249 ia = ip_rtaddr(ipaddr.sin_addr);
1250 if (ia == 0) {
1251 type = ICMP_UNREACH;
1252 code = ICMP_UNREACH_SRCFAIL;
1253 goto bad;
1254 }
1255 ip->ip_dst = ipaddr.sin_addr;
1256 bcopy((caddr_t)&ia->ia_addr.sin_addr,
1257 (caddr_t)(cp + off), sizeof(struct in_addr));
1258 cp[IPOPT_OFFSET] += sizeof(struct in_addr);
1259 /*
1260 * Let ip_intr's mcast routing check handle mcast pkts
1261 */
1262 forward = !IN_MULTICAST(ip->ip_dst.s_addr);
1263 break;
1264
1265 case IPOPT_RR:
1266 if (optlen < IPOPT_OFFSET + sizeof(*cp)) {
1267 code = &cp[IPOPT_OLEN] - (u_char *)ip;
1268 goto bad;
1269 }
1270 if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) {
1271 code = &cp[IPOPT_OFFSET] - (u_char *)ip;
1272 goto bad;
1273 }
1274 /*
1275 * If no space remains, ignore.
1276 */
1277 off--; /* 0 origin */
1278 if ((off + sizeof(struct in_addr)) > optlen)
1279 break;
1280 bcopy((caddr_t)(&ip->ip_dst), (caddr_t)&ipaddr.sin_addr,
1281 sizeof(ipaddr.sin_addr));
1282 /*
1283 * locate outgoing interface; if we're the destination,
1284 * use the incoming interface (should be same).
1285 */
1286 if ((ia = ifatoia(ifa_ifwithaddr(sintosa(&ipaddr))))
1287 == NULL &&
1288 (ia = ip_rtaddr(ipaddr.sin_addr)) == NULL) {
1289 type = ICMP_UNREACH;
1290 code = ICMP_UNREACH_HOST;
1291 goto bad;
1292 }
1293 bcopy((caddr_t)&ia->ia_addr.sin_addr,
1294 (caddr_t)(cp + off), sizeof(struct in_addr));
1295 cp[IPOPT_OFFSET] += sizeof(struct in_addr);
1296 break;
1297
1298 case IPOPT_TS:
1299 code = cp - (u_char *)ip;
1300 ipt = (struct ip_timestamp *)cp;
1301 if (ipt->ipt_len < 4 || ipt->ipt_len > 40) {
1302 code = (u_char *)&ipt->ipt_len - (u_char *)ip;
1303 goto bad;
1304 }
1305 if (ipt->ipt_ptr < 5) {
1306 code = (u_char *)&ipt->ipt_ptr - (u_char *)ip;
1307 goto bad;
1308 }
1309 if (ipt->ipt_ptr > ipt->ipt_len - sizeof (int32_t)) {
1310 if (++ipt->ipt_oflw == 0) {
1311 code = (u_char *)&ipt->ipt_ptr -
1312 (u_char *)ip;
1313 goto bad;
1314 }
1315 break;
1316 }
1317 cp0 = (cp + ipt->ipt_ptr - 1);
1318 switch (ipt->ipt_flg) {
1319
1320 case IPOPT_TS_TSONLY:
1321 break;
1322
1323 case IPOPT_TS_TSANDADDR:
1324 if (ipt->ipt_ptr - 1 + sizeof(n_time) +
1325 sizeof(struct in_addr) > ipt->ipt_len) {
1326 code = (u_char *)&ipt->ipt_ptr -
1327 (u_char *)ip;
1328 goto bad;
1329 }
1330 ipaddr.sin_addr = dst;
1331 ia = ifatoia(ifaof_ifpforaddr(sintosa(&ipaddr),
1332 m->m_pkthdr.rcvif));
1333 if (ia == 0)
1334 continue;
1335 bcopy(&ia->ia_addr.sin_addr,
1336 cp0, sizeof(struct in_addr));
1337 ipt->ipt_ptr += sizeof(struct in_addr);
1338 break;
1339
1340 case IPOPT_TS_PRESPEC:
1341 if (ipt->ipt_ptr - 1 + sizeof(n_time) +
1342 sizeof(struct in_addr) > ipt->ipt_len) {
1343 code = (u_char *)&ipt->ipt_ptr -
1344 (u_char *)ip;
1345 goto bad;
1346 }
1347 bcopy(cp0, &ipaddr.sin_addr,
1348 sizeof(struct in_addr));
1349 if (ifatoia(ifa_ifwithaddr(sintosa(&ipaddr)))
1350 == NULL)
1351 continue;
1352 ipt->ipt_ptr += sizeof(struct in_addr);
1353 break;
1354
1355 default:
1356 /* XXX can't take &ipt->ipt_flg */
1357 code = (u_char *)&ipt->ipt_ptr -
1358 (u_char *)ip + 1;
1359 goto bad;
1360 }
1361 ntime = iptime();
1362 cp0 = (u_char *) &ntime; /* XXX grumble, GCC... */
1363 bcopy(cp0, (caddr_t)cp + ipt->ipt_ptr - 1,
1364 sizeof(n_time));
1365 ipt->ipt_ptr += sizeof(n_time);
1366 }
1367 }
1368 if (forward) {
1369 if (ip_forwsrcrt == 0) {
1370 type = ICMP_UNREACH;
1371 code = ICMP_UNREACH_SRCFAIL;
1372 goto bad;
1373 }
1374 ip_forward(m, 1);
1375 return (1);
1376 }
1377 return (0);
1378 bad:
1379 icmp_error(m, type, code, 0, 0);
1380 ipstat.ips_badoptions++;
1381 return (1);
1382 }
1383
1384 /*
1385 * Given address of next destination (final or next hop),
1386 * return internet address info of interface to be used to get there.
1387 */
1388 struct in_ifaddr *
1389 ip_rtaddr(dst)
1390 struct in_addr dst;
1391 {
1392 struct sockaddr_in *sin;
1393
1394 sin = satosin(&ipforward_rt.ro_dst);
1395
1396 if (ipforward_rt.ro_rt == 0 || !in_hosteq(dst, sin->sin_addr)) {
1397 if (ipforward_rt.ro_rt) {
1398 RTFREE(ipforward_rt.ro_rt);
1399 ipforward_rt.ro_rt = 0;
1400 }
1401 sin->sin_family = AF_INET;
1402 sin->sin_len = sizeof(*sin);
1403 sin->sin_addr = dst;
1404
1405 rtalloc(&ipforward_rt);
1406 }
1407 if (ipforward_rt.ro_rt == 0)
1408 return ((struct in_ifaddr *)0);
1409 return (ifatoia(ipforward_rt.ro_rt->rt_ifa));
1410 }
1411
1412 /*
1413 * Save incoming source route for use in replies,
1414 * to be picked up later by ip_srcroute if the receiver is interested.
1415 */
1416 void
1417 save_rte(option, dst)
1418 u_char *option;
1419 struct in_addr dst;
1420 {
1421 unsigned olen;
1422
1423 olen = option[IPOPT_OLEN];
1424 #ifdef DIAGNOSTIC
1425 if (ipprintfs)
1426 printf("save_rte: olen %d\n", olen);
1427 #endif /* 0 */
1428 if (olen > sizeof(ip_srcrt) - (1 + sizeof(dst)))
1429 return;
1430 bcopy((caddr_t)option, (caddr_t)ip_srcrt.srcopt, olen);
1431 ip_nhops = (olen - IPOPT_OFFSET - 1) / sizeof(struct in_addr);
1432 ip_srcrt.dst = dst;
1433 }
1434
1435 /*
1436 * Retrieve incoming source route for use in replies,
1437 * in the same form used by setsockopt.
1438 * The first hop is placed before the options, will be removed later.
1439 */
1440 struct mbuf *
1441 ip_srcroute()
1442 {
1443 struct in_addr *p, *q;
1444 struct mbuf *m;
1445
1446 if (ip_nhops == 0)
1447 return ((struct mbuf *)0);
1448 m = m_get(M_DONTWAIT, MT_SOOPTS);
1449 if (m == 0)
1450 return ((struct mbuf *)0);
1451
1452 MCLAIM(m, &inetdomain.dom_mowner);
1453 #define OPTSIZ (sizeof(ip_srcrt.nop) + sizeof(ip_srcrt.srcopt))
1454
1455 /* length is (nhops+1)*sizeof(addr) + sizeof(nop + srcrt header) */
1456 m->m_len = ip_nhops * sizeof(struct in_addr) + sizeof(struct in_addr) +
1457 OPTSIZ;
1458 #ifdef DIAGNOSTIC
1459 if (ipprintfs)
1460 printf("ip_srcroute: nhops %d mlen %d", ip_nhops, m->m_len);
1461 #endif
1462
1463 /*
1464 * First save first hop for return route
1465 */
1466 p = &ip_srcrt.route[ip_nhops - 1];
1467 *(mtod(m, struct in_addr *)) = *p--;
1468 #ifdef DIAGNOSTIC
1469 if (ipprintfs)
1470 printf(" hops %x", ntohl(mtod(m, struct in_addr *)->s_addr));
1471 #endif
1472
1473 /*
1474 * Copy option fields and padding (nop) to mbuf.
1475 */
1476 ip_srcrt.nop = IPOPT_NOP;
1477 ip_srcrt.srcopt[IPOPT_OFFSET] = IPOPT_MINOFF;
1478 bcopy((caddr_t)&ip_srcrt.nop,
1479 mtod(m, caddr_t) + sizeof(struct in_addr), OPTSIZ);
1480 q = (struct in_addr *)(mtod(m, caddr_t) +
1481 sizeof(struct in_addr) + OPTSIZ);
1482 #undef OPTSIZ
1483 /*
1484 * Record return path as an IP source route,
1485 * reversing the path (pointers are now aligned).
1486 */
1487 while (p >= ip_srcrt.route) {
1488 #ifdef DIAGNOSTIC
1489 if (ipprintfs)
1490 printf(" %x", ntohl(q->s_addr));
1491 #endif
1492 *q++ = *p--;
1493 }
1494 /*
1495 * Last hop goes to final destination.
1496 */
1497 *q = ip_srcrt.dst;
1498 #ifdef DIAGNOSTIC
1499 if (ipprintfs)
1500 printf(" %x\n", ntohl(q->s_addr));
1501 #endif
1502 return (m);
1503 }
1504
1505 /*
1506 * Strip out IP options, at higher
1507 * level protocol in the kernel.
1508 * Second argument is buffer to which options
1509 * will be moved, and return value is their length.
1510 * XXX should be deleted; last arg currently ignored.
1511 */
1512 void
1513 ip_stripoptions(m, mopt)
1514 struct mbuf *m;
1515 struct mbuf *mopt;
1516 {
1517 int i;
1518 struct ip *ip = mtod(m, struct ip *);
1519 caddr_t opts;
1520 int olen;
1521
1522 olen = (ip->ip_hl << 2) - sizeof (struct ip);
1523 opts = (caddr_t)(ip + 1);
1524 i = m->m_len - (sizeof (struct ip) + olen);
1525 bcopy(opts + olen, opts, (unsigned)i);
1526 m->m_len -= olen;
1527 if (m->m_flags & M_PKTHDR)
1528 m->m_pkthdr.len -= olen;
1529 ip->ip_len = htons(ntohs(ip->ip_len) - olen);
1530 ip->ip_hl = sizeof (struct ip) >> 2;
1531 }
1532
1533 const int inetctlerrmap[PRC_NCMDS] = {
1534 0, 0, 0, 0,
1535 0, EMSGSIZE, EHOSTDOWN, EHOSTUNREACH,
1536 EHOSTUNREACH, EHOSTUNREACH, ECONNREFUSED, ECONNREFUSED,
1537 EMSGSIZE, EHOSTUNREACH, 0, 0,
1538 0, 0, 0, 0,
1539 ENOPROTOOPT
1540 };
1541
1542 /*
1543 * Forward a packet. If some error occurs return the sender
1544 * an icmp packet. Note we can't always generate a meaningful
1545 * icmp message because icmp doesn't have a large enough repertoire
1546 * of codes and types.
1547 *
1548 * If not forwarding, just drop the packet. This could be confusing
1549 * if ipforwarding was zero but some routing protocol was advancing
1550 * us as a gateway to somewhere. However, we must let the routing
1551 * protocol deal with that.
1552 *
1553 * The srcrt parameter indicates whether the packet is being forwarded
1554 * via a source route.
1555 */
1556 void
1557 ip_forward(m, srcrt)
1558 struct mbuf *m;
1559 int srcrt;
1560 {
1561 struct ip *ip = mtod(m, struct ip *);
1562 struct sockaddr_in *sin;
1563 struct rtentry *rt;
1564 int error, type = 0, code = 0;
1565 struct mbuf *mcopy;
1566 n_long dest;
1567 struct ifnet *destifp;
1568 #ifdef IPSEC
1569 struct ifnet dummyifp;
1570 #endif
1571
1572 /*
1573 * We are now in the output path.
1574 */
1575 MCLAIM(m, &ip_tx_mowner);
1576
1577 /*
1578 * Clear any in-bound checksum flags for this packet.
1579 */
1580 m->m_pkthdr.csum_flags = 0;
1581
1582 dest = 0;
1583 #ifdef DIAGNOSTIC
1584 if (ipprintfs)
1585 printf("forward: src %2.2x dst %2.2x ttl %x\n",
1586 ntohl(ip->ip_src.s_addr),
1587 ntohl(ip->ip_dst.s_addr), ip->ip_ttl);
1588 #endif
1589 if (m->m_flags & (M_BCAST|M_MCAST) || in_canforward(ip->ip_dst) == 0) {
1590 ipstat.ips_cantforward++;
1591 m_freem(m);
1592 return;
1593 }
1594 if (ip->ip_ttl <= IPTTLDEC) {
1595 icmp_error(m, ICMP_TIMXCEED, ICMP_TIMXCEED_INTRANS, dest, 0);
1596 return;
1597 }
1598 ip->ip_ttl -= IPTTLDEC;
1599
1600 sin = satosin(&ipforward_rt.ro_dst);
1601 if ((rt = ipforward_rt.ro_rt) == 0 ||
1602 !in_hosteq(ip->ip_dst, sin->sin_addr)) {
1603 if (ipforward_rt.ro_rt) {
1604 RTFREE(ipforward_rt.ro_rt);
1605 ipforward_rt.ro_rt = 0;
1606 }
1607 sin->sin_family = AF_INET;
1608 sin->sin_len = sizeof(struct sockaddr_in);
1609 sin->sin_addr = ip->ip_dst;
1610
1611 rtalloc(&ipforward_rt);
1612 if (ipforward_rt.ro_rt == 0) {
1613 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_HOST, dest, 0);
1614 return;
1615 }
1616 rt = ipforward_rt.ro_rt;
1617 }
1618
1619 /*
1620 * Save at most 68 bytes of the packet in case
1621 * we need to generate an ICMP message to the src.
1622 * Pullup to avoid sharing mbuf cluster between m and mcopy.
1623 */
1624 mcopy = m_copym(m, 0, imin(ntohs(ip->ip_len), 68), M_DONTWAIT);
1625 if (mcopy)
1626 mcopy = m_pullup(mcopy, ip->ip_hl << 2);
1627
1628 /*
1629 * If forwarding packet using same interface that it came in on,
1630 * perhaps should send a redirect to sender to shortcut a hop.
1631 * Only send redirect if source is sending directly to us,
1632 * and if packet was not source routed (or has any options).
1633 * Also, don't send redirect if forwarding using a default route
1634 * or a route modified by a redirect.
1635 */
1636 if (rt->rt_ifp == m->m_pkthdr.rcvif &&
1637 (rt->rt_flags & (RTF_DYNAMIC|RTF_MODIFIED)) == 0 &&
1638 !in_nullhost(satosin(rt_key(rt))->sin_addr) &&
1639 ipsendredirects && !srcrt) {
1640 if (rt->rt_ifa &&
1641 (ip->ip_src.s_addr & ifatoia(rt->rt_ifa)->ia_subnetmask) ==
1642 ifatoia(rt->rt_ifa)->ia_subnet) {
1643 if (rt->rt_flags & RTF_GATEWAY)
1644 dest = satosin(rt->rt_gateway)->sin_addr.s_addr;
1645 else
1646 dest = ip->ip_dst.s_addr;
1647 /*
1648 * Router requirements says to only send host
1649 * redirects.
1650 */
1651 type = ICMP_REDIRECT;
1652 code = ICMP_REDIRECT_HOST;
1653 #ifdef DIAGNOSTIC
1654 if (ipprintfs)
1655 printf("redirect (%d) to %x\n", code,
1656 (u_int32_t)dest);
1657 #endif
1658 }
1659 }
1660
1661 #ifdef IPSEC
1662 /* Don't lookup socket in forwarding case */
1663 (void)ipsec_setsocket(m, NULL);
1664 #endif
1665 error = ip_output(m, (struct mbuf *)0, &ipforward_rt,
1666 (IP_FORWARDING | (ip_directedbcast ? IP_ALLOWBROADCAST : 0)), 0);
1667 if (error)
1668 ipstat.ips_cantforward++;
1669 else {
1670 ipstat.ips_forward++;
1671 if (type)
1672 ipstat.ips_redirectsent++;
1673 else {
1674 if (mcopy) {
1675 #ifdef GATEWAY
1676 if (mcopy->m_flags & M_CANFASTFWD)
1677 ipflow_create(&ipforward_rt, mcopy);
1678 #endif
1679 m_freem(mcopy);
1680 }
1681 return;
1682 }
1683 }
1684 if (mcopy == NULL)
1685 return;
1686 destifp = NULL;
1687
1688 switch (error) {
1689
1690 case 0: /* forwarded, but need redirect */
1691 /* type, code set above */
1692 break;
1693
1694 case ENETUNREACH: /* shouldn't happen, checked above */
1695 case EHOSTUNREACH:
1696 case ENETDOWN:
1697 case EHOSTDOWN:
1698 default:
1699 type = ICMP_UNREACH;
1700 code = ICMP_UNREACH_HOST;
1701 break;
1702
1703 case EMSGSIZE:
1704 type = ICMP_UNREACH;
1705 code = ICMP_UNREACH_NEEDFRAG;
1706 #ifndef IPSEC
1707 if (ipforward_rt.ro_rt)
1708 destifp = ipforward_rt.ro_rt->rt_ifp;
1709 #else
1710 /*
1711 * If the packet is routed over IPsec tunnel, tell the
1712 * originator the tunnel MTU.
1713 * tunnel MTU = if MTU - sizeof(IP) - ESP/AH hdrsiz
1714 * XXX quickhack!!!
1715 */
1716 if (ipforward_rt.ro_rt) {
1717 struct secpolicy *sp;
1718 int ipsecerror;
1719 size_t ipsechdr;
1720 struct route *ro;
1721
1722 sp = ipsec4_getpolicybyaddr(mcopy,
1723 IPSEC_DIR_OUTBOUND,
1724 IP_FORWARDING,
1725 &ipsecerror);
1726
1727 if (sp == NULL)
1728 destifp = ipforward_rt.ro_rt->rt_ifp;
1729 else {
1730 /* count IPsec header size */
1731 ipsechdr = ipsec4_hdrsiz(mcopy,
1732 IPSEC_DIR_OUTBOUND,
1733 NULL);
1734
1735 /*
1736 * find the correct route for outer IPv4
1737 * header, compute tunnel MTU.
1738 *
1739 * XXX BUG ALERT
1740 * The "dummyifp" code relies upon the fact
1741 * that icmp_error() touches only ifp->if_mtu.
1742 */
1743 /*XXX*/
1744 destifp = NULL;
1745 if (sp->req != NULL
1746 && sp->req->sav != NULL
1747 && sp->req->sav->sah != NULL) {
1748 ro = &sp->req->sav->sah->sa_route;
1749 if (ro->ro_rt && ro->ro_rt->rt_ifp) {
1750 dummyifp.if_mtu =
1751 ro->ro_rt->rt_rmx.rmx_mtu ?
1752 ro->ro_rt->rt_rmx.rmx_mtu :
1753 ro->ro_rt->rt_ifp->if_mtu;
1754 dummyifp.if_mtu -= ipsechdr;
1755 destifp = &dummyifp;
1756 }
1757 }
1758
1759 key_freesp(sp);
1760 }
1761 }
1762 #endif /*IPSEC*/
1763 ipstat.ips_cantfrag++;
1764 break;
1765
1766 case ENOBUFS:
1767 #if 1
1768 /*
1769 * a router should not generate ICMP_SOURCEQUENCH as
1770 * required in RFC1812 Requirements for IP Version 4 Routers.
1771 * source quench could be a big problem under DoS attacks,
1772 * or if the underlying interface is rate-limited.
1773 */
1774 if (mcopy)
1775 m_freem(mcopy);
1776 return;
1777 #else
1778 type = ICMP_SOURCEQUENCH;
1779 code = 0;
1780 break;
1781 #endif
1782 }
1783 icmp_error(mcopy, type, code, dest, destifp);
1784 }
1785
1786 void
1787 ip_savecontrol(inp, mp, ip, m)
1788 struct inpcb *inp;
1789 struct mbuf **mp;
1790 struct ip *ip;
1791 struct mbuf *m;
1792 {
1793
1794 if (inp->inp_socket->so_options & SO_TIMESTAMP) {
1795 struct timeval tv;
1796
1797 microtime(&tv);
1798 *mp = sbcreatecontrol((caddr_t) &tv, sizeof(tv),
1799 SCM_TIMESTAMP, SOL_SOCKET);
1800 if (*mp)
1801 mp = &(*mp)->m_next;
1802 }
1803 if (inp->inp_flags & INP_RECVDSTADDR) {
1804 *mp = sbcreatecontrol((caddr_t) &ip->ip_dst,
1805 sizeof(struct in_addr), IP_RECVDSTADDR, IPPROTO_IP);
1806 if (*mp)
1807 mp = &(*mp)->m_next;
1808 }
1809 #ifdef notyet
1810 /*
1811 * XXX
1812 * Moving these out of udp_input() made them even more broken
1813 * than they already were.
1814 * - fenner (at) parc.xerox.com
1815 */
1816 /* options were tossed already */
1817 if (inp->inp_flags & INP_RECVOPTS) {
1818 *mp = sbcreatecontrol((caddr_t) opts_deleted_above,
1819 sizeof(struct in_addr), IP_RECVOPTS, IPPROTO_IP);
1820 if (*mp)
1821 mp = &(*mp)->m_next;
1822 }
1823 /* ip_srcroute doesn't do what we want here, need to fix */
1824 if (inp->inp_flags & INP_RECVRETOPTS) {
1825 *mp = sbcreatecontrol((caddr_t) ip_srcroute(),
1826 sizeof(struct in_addr), IP_RECVRETOPTS, IPPROTO_IP);
1827 if (*mp)
1828 mp = &(*mp)->m_next;
1829 }
1830 #endif
1831 if (inp->inp_flags & INP_RECVIF) {
1832 struct sockaddr_dl sdl;
1833
1834 sdl.sdl_len = offsetof(struct sockaddr_dl, sdl_data[0]);
1835 sdl.sdl_family = AF_LINK;
1836 sdl.sdl_index = m->m_pkthdr.rcvif ?
1837 m->m_pkthdr.rcvif->if_index : 0;
1838 sdl.sdl_nlen = sdl.sdl_alen = sdl.sdl_slen = 0;
1839 *mp = sbcreatecontrol((caddr_t) &sdl, sdl.sdl_len,
1840 IP_RECVIF, IPPROTO_IP);
1841 if (*mp)
1842 mp = &(*mp)->m_next;
1843 }
1844 }
1845
1846 int
1847 ip_sysctl(name, namelen, oldp, oldlenp, newp, newlen)
1848 int *name;
1849 u_int namelen;
1850 void *oldp;
1851 size_t *oldlenp;
1852 void *newp;
1853 size_t newlen;
1854 {
1855 extern int subnetsarelocal, hostzeroisbroadcast;
1856
1857 int error, old;
1858
1859 /* All sysctl names at this level are terminal. */
1860 if (namelen != 1)
1861 return (ENOTDIR);
1862
1863 switch (name[0]) {
1864 case IPCTL_FORWARDING:
1865 return (sysctl_int(oldp, oldlenp, newp, newlen, &ipforwarding));
1866 case IPCTL_SENDREDIRECTS:
1867 return (sysctl_int(oldp, oldlenp, newp, newlen,
1868 &ipsendredirects));
1869 case IPCTL_DEFTTL:
1870 return (sysctl_int(oldp, oldlenp, newp, newlen, &ip_defttl));
1871 #ifdef notyet
1872 case IPCTL_DEFMTU:
1873 return (sysctl_int(oldp, oldlenp, newp, newlen, &ip_mtu));
1874 #endif
1875 case IPCTL_FORWSRCRT:
1876 /* Don't allow this to change in a secure environment. */
1877 if (securelevel > 0)
1878 return (sysctl_rdint(oldp, oldlenp, newp,
1879 ip_forwsrcrt));
1880 else
1881 return (sysctl_int(oldp, oldlenp, newp, newlen,
1882 &ip_forwsrcrt));
1883 case IPCTL_DIRECTEDBCAST:
1884 return (sysctl_int(oldp, oldlenp, newp, newlen,
1885 &ip_directedbcast));
1886 case IPCTL_ALLOWSRCRT:
1887 return (sysctl_int(oldp, oldlenp, newp, newlen,
1888 &ip_allowsrcrt));
1889 case IPCTL_SUBNETSARELOCAL:
1890 return (sysctl_int(oldp, oldlenp, newp, newlen,
1891 &subnetsarelocal));
1892 case IPCTL_MTUDISC:
1893 error = sysctl_int(oldp, oldlenp, newp, newlen,
1894 &ip_mtudisc);
1895 if (error == 0 && ip_mtudisc == 0)
1896 rt_timer_queue_remove_all(ip_mtudisc_timeout_q, TRUE);
1897 return error;
1898 case IPCTL_ANONPORTMIN:
1899 old = anonportmin;
1900 error = sysctl_int(oldp, oldlenp, newp, newlen, &anonportmin);
1901 if (anonportmin >= anonportmax || anonportmin < 0
1902 || anonportmin > 65535
1903 #ifndef IPNOPRIVPORTS
1904 || anonportmin < IPPORT_RESERVED
1905 #endif
1906 ) {
1907 anonportmin = old;
1908 return (EINVAL);
1909 }
1910 return (error);
1911 case IPCTL_ANONPORTMAX:
1912 old = anonportmax;
1913 error = sysctl_int(oldp, oldlenp, newp, newlen, &anonportmax);
1914 if (anonportmin >= anonportmax || anonportmax < 0
1915 || anonportmax > 65535
1916 #ifndef IPNOPRIVPORTS
1917 || anonportmax < IPPORT_RESERVED
1918 #endif
1919 ) {
1920 anonportmax = old;
1921 return (EINVAL);
1922 }
1923 return (error);
1924 case IPCTL_MTUDISCTIMEOUT:
1925 old = ip_mtudisc_timeout;
1926 error = sysctl_int(oldp, oldlenp, newp, newlen,
1927 &ip_mtudisc_timeout);
1928 if (ip_mtudisc_timeout < 0) {
1929 ip_mtudisc_timeout = old;
1930 return (EINVAL);
1931 }
1932 if (error == 0)
1933 rt_timer_queue_change(ip_mtudisc_timeout_q,
1934 ip_mtudisc_timeout);
1935 return (error);
1936 #ifdef GATEWAY
1937 case IPCTL_MAXFLOWS:
1938 {
1939 int s;
1940
1941 error = sysctl_int(oldp, oldlenp, newp, newlen,
1942 &ip_maxflows);
1943 s = splsoftnet();
1944 ipflow_reap(0);
1945 splx(s);
1946 return (error);
1947 }
1948 #endif
1949 case IPCTL_HOSTZEROBROADCAST:
1950 return (sysctl_int(oldp, oldlenp, newp, newlen,
1951 &hostzeroisbroadcast));
1952 #if NGIF > 0
1953 case IPCTL_GIF_TTL:
1954 return (sysctl_int(oldp, oldlenp, newp, newlen,
1955 &ip_gif_ttl));
1956 #endif
1957
1958 #if NGRE > 0
1959 case IPCTL_GRE_TTL:
1960 return (sysctl_int(oldp, oldlenp, newp, newlen,
1961 &ip_gre_ttl));
1962 #endif
1963
1964 #ifndef IPNOPRIVPORTS
1965 case IPCTL_LOWPORTMIN:
1966 old = lowportmin;
1967 error = sysctl_int(oldp, oldlenp, newp, newlen, &lowportmin);
1968 if (lowportmin >= lowportmax
1969 || lowportmin > IPPORT_RESERVEDMAX
1970 || lowportmin < IPPORT_RESERVEDMIN
1971 ) {
1972 lowportmin = old;
1973 return (EINVAL);
1974 }
1975 return (error);
1976 case IPCTL_LOWPORTMAX:
1977 old = lowportmax;
1978 error = sysctl_int(oldp, oldlenp, newp, newlen, &lowportmax);
1979 if (lowportmin >= lowportmax
1980 || lowportmax > IPPORT_RESERVEDMAX
1981 || lowportmax < IPPORT_RESERVEDMIN
1982 ) {
1983 lowportmax = old;
1984 return (EINVAL);
1985 }
1986 return (error);
1987 #endif
1988
1989 case IPCTL_MAXFRAGPACKETS:
1990 return (sysctl_int(oldp, oldlenp, newp, newlen,
1991 &ip_maxfragpackets));
1992
1993 case IPCTL_CHECKINTERFACE:
1994 return (sysctl_int(oldp, oldlenp, newp, newlen,
1995 &ip_checkinterface));
1996 default:
1997 return (EOPNOTSUPP);
1998 }
1999 /* NOTREACHED */
2000 }
2001