ip_input.c revision 1.156 1 /* $NetBSD: ip_input.c,v 1.156 2002/09/11 02:41:19 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 1.156 2002/09/11 02:41:19 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_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 struct rttimer_queue *ip_mtudisc_timeout_q = NULL;
201
202 extern struct domain inetdomain;
203 int ipqmaxlen = IFQ_MAXLEN;
204 u_long in_ifaddrhash; /* size of hash table - 1 */
205 int in_ifaddrentries; /* total number of addrs */
206 struct in_ifaddrhead in_ifaddr;
207 struct in_ifaddrhashhead *in_ifaddrhashtbl;
208 struct ifqueue ipintrq;
209 struct ipstat ipstat;
210 u_int16_t ip_id;
211
212 #ifdef PFIL_HOOKS
213 struct pfil_head inet_pfil_hook;
214 #endif
215
216 struct ipqhead ipq;
217 int ipq_locked;
218 int ip_nfragpackets = 0;
219 int ip_maxfragpackets = 200;
220
221 static __inline int ipq_lock_try __P((void));
222 static __inline void ipq_unlock __P((void));
223
224 static __inline int
225 ipq_lock_try()
226 {
227 int s;
228
229 /*
230 * Use splvm() -- we're blocking things that would cause
231 * mbuf allocation.
232 */
233 s = splvm();
234 if (ipq_locked) {
235 splx(s);
236 return (0);
237 }
238 ipq_locked = 1;
239 splx(s);
240 return (1);
241 }
242
243 static __inline void
244 ipq_unlock()
245 {
246 int s;
247
248 s = splvm();
249 ipq_locked = 0;
250 splx(s);
251 }
252
253 #ifdef DIAGNOSTIC
254 #define IPQ_LOCK() \
255 do { \
256 if (ipq_lock_try() == 0) { \
257 printf("%s:%d: ipq already locked\n", __FILE__, __LINE__); \
258 panic("ipq_lock"); \
259 } \
260 } while (0)
261 #define IPQ_LOCK_CHECK() \
262 do { \
263 if (ipq_locked == 0) { \
264 printf("%s:%d: ipq lock not held\n", __FILE__, __LINE__); \
265 panic("ipq lock check"); \
266 } \
267 } while (0)
268 #else
269 #define IPQ_LOCK() (void) ipq_lock_try()
270 #define IPQ_LOCK_CHECK() /* nothing */
271 #endif
272
273 #define IPQ_UNLOCK() ipq_unlock()
274
275 struct pool ipqent_pool;
276
277 #ifdef INET_CSUM_COUNTERS
278 #include <sys/device.h>
279
280 struct evcnt ip_hwcsum_bad = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
281 NULL, "inet", "hwcsum bad");
282 struct evcnt ip_hwcsum_ok = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
283 NULL, "inet", "hwcsum ok");
284 struct evcnt ip_swcsum = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
285 NULL, "inet", "swcsum");
286
287 #define INET_CSUM_COUNTER_INCR(ev) (ev)->ev_count++
288
289 #else
290
291 #define INET_CSUM_COUNTER_INCR(ev) /* nothing */
292
293 #endif /* INET_CSUM_COUNTERS */
294
295 /*
296 * We need to save the IP options in case a protocol wants to respond
297 * to an incoming packet over the same route if the packet got here
298 * using IP source routing. This allows connection establishment and
299 * maintenance when the remote end is on a network that is not known
300 * to us.
301 */
302 int ip_nhops = 0;
303 static struct ip_srcrt {
304 struct in_addr dst; /* final destination */
305 char nop; /* one NOP to align */
306 char srcopt[IPOPT_OFFSET + 1]; /* OPTVAL, OLEN and OFFSET */
307 struct in_addr route[MAX_IPOPTLEN/sizeof(struct in_addr)];
308 } ip_srcrt;
309
310 static void save_rte __P((u_char *, struct in_addr));
311
312 /*
313 * IP initialization: fill in IP protocol switch table.
314 * All protocols not implemented in kernel go to raw IP protocol handler.
315 */
316 void
317 ip_init()
318 {
319 struct protosw *pr;
320 int i;
321
322 pool_init(&ipqent_pool, sizeof(struct ipqent), 0, 0, 0, "ipqepl",
323 NULL);
324
325 pr = pffindproto(PF_INET, IPPROTO_RAW, SOCK_RAW);
326 if (pr == 0)
327 panic("ip_init");
328 for (i = 0; i < IPPROTO_MAX; i++)
329 ip_protox[i] = pr - inetsw;
330 for (pr = inetdomain.dom_protosw;
331 pr < inetdomain.dom_protoswNPROTOSW; pr++)
332 if (pr->pr_domain->dom_family == PF_INET &&
333 pr->pr_protocol && pr->pr_protocol != IPPROTO_RAW)
334 ip_protox[pr->pr_protocol] = pr - inetsw;
335 LIST_INIT(&ipq);
336 ip_id = time.tv_sec & 0xffff;
337 ipintrq.ifq_maxlen = ipqmaxlen;
338 TAILQ_INIT(&in_ifaddr);
339 in_ifaddrhashtbl = hashinit(IN_IFADDR_HASH_SIZE, HASH_LIST, M_IFADDR,
340 M_WAITOK, &in_ifaddrhash);
341 if (ip_mtudisc != 0)
342 ip_mtudisc_timeout_q =
343 rt_timer_queue_create(ip_mtudisc_timeout);
344 #ifdef GATEWAY
345 ipflow_init();
346 #endif
347
348 #ifdef PFIL_HOOKS
349 /* Register our Packet Filter hook. */
350 inet_pfil_hook.ph_type = PFIL_TYPE_AF;
351 inet_pfil_hook.ph_af = AF_INET;
352 i = pfil_head_register(&inet_pfil_hook);
353 if (i != 0)
354 printf("ip_init: WARNING: unable to register pfil hook, "
355 "error %d\n", i);
356 #endif /* PFIL_HOOKS */
357
358 #ifdef INET_CSUM_COUNTERS
359 evcnt_attach_static(&ip_hwcsum_bad);
360 evcnt_attach_static(&ip_hwcsum_ok);
361 evcnt_attach_static(&ip_swcsum);
362 #endif /* INET_CSUM_COUNTERS */
363 }
364
365 struct sockaddr_in ipaddr = { sizeof(ipaddr), AF_INET };
366 struct route ipforward_rt;
367
368 /*
369 * IP software interrupt routine
370 */
371 void
372 ipintr()
373 {
374 int s;
375 struct mbuf *m;
376
377 while (1) {
378 s = splnet();
379 IF_DEQUEUE(&ipintrq, m);
380 splx(s);
381 if (m == 0)
382 return;
383 ip_input(m);
384 }
385 }
386
387 /*
388 * Ip input routine. Checksum and byte swap header. If fragmented
389 * try to reassemble. Process options. Pass to next level.
390 */
391 void
392 ip_input(struct mbuf *m)
393 {
394 struct ip *ip = NULL;
395 struct ipq *fp;
396 struct in_ifaddr *ia;
397 struct ifaddr *ifa;
398 struct ipqent *ipqe;
399 int hlen = 0, mff, len;
400 int downmatch;
401
402 #ifdef DIAGNOSTIC
403 if ((m->m_flags & M_PKTHDR) == 0)
404 panic("ipintr no HDR");
405 #endif
406 #ifdef IPSEC
407 /*
408 * should the inner packet be considered authentic?
409 * see comment in ah4_input().
410 */
411 if (m) {
412 m->m_flags &= ~M_AUTHIPHDR;
413 m->m_flags &= ~M_AUTHIPDGM;
414 }
415 #endif
416 /*
417 * If no IP addresses have been set yet but the interfaces
418 * are receiving, can't do anything with incoming packets yet.
419 */
420 if (TAILQ_FIRST(&in_ifaddr) == 0)
421 goto bad;
422 ipstat.ips_total++;
423 /*
424 * If the IP header is not aligned, slurp it up into a new
425 * mbuf with space for link headers, in the event we forward
426 * it. Otherwise, if it is aligned, make sure the entire
427 * base IP header is in the first mbuf of the chain.
428 */
429 if (IP_HDR_ALIGNED_P(mtod(m, caddr_t)) == 0) {
430 if ((m = m_copyup(m, sizeof(struct ip),
431 (max_linkhdr + 3) & ~3)) == NULL) {
432 /* XXXJRT new stat, please */
433 ipstat.ips_toosmall++;
434 return;
435 }
436 } else if (__predict_false(m->m_len < sizeof (struct ip))) {
437 if ((m = m_pullup(m, sizeof (struct ip))) == NULL) {
438 ipstat.ips_toosmall++;
439 return;
440 }
441 }
442 ip = mtod(m, struct ip *);
443 if (ip->ip_v != IPVERSION) {
444 ipstat.ips_badvers++;
445 goto bad;
446 }
447 hlen = ip->ip_hl << 2;
448 if (hlen < sizeof(struct ip)) { /* minimum header length */
449 ipstat.ips_badhlen++;
450 goto bad;
451 }
452 if (hlen > m->m_len) {
453 if ((m = m_pullup(m, hlen)) == 0) {
454 ipstat.ips_badhlen++;
455 return;
456 }
457 ip = mtod(m, struct ip *);
458 }
459
460 /*
461 * RFC1122: packets with a multicast source address are
462 * not allowed.
463 */
464 if (IN_MULTICAST(ip->ip_src.s_addr)) {
465 ipstat.ips_badaddr++;
466 goto bad;
467 }
468
469 /* 127/8 must not appear on wire - RFC1122 */
470 if ((ntohl(ip->ip_dst.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET ||
471 (ntohl(ip->ip_src.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET) {
472 if ((m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) == 0) {
473 ipstat.ips_badaddr++;
474 goto bad;
475 }
476 }
477
478 switch (m->m_pkthdr.csum_flags &
479 ((m->m_pkthdr.rcvif->if_csum_flags_rx & M_CSUM_IPv4) |
480 M_CSUM_IPv4_BAD)) {
481 case M_CSUM_IPv4|M_CSUM_IPv4_BAD:
482 INET_CSUM_COUNTER_INCR(&ip_hwcsum_bad);
483 goto badcsum;
484
485 case M_CSUM_IPv4:
486 /* Checksum was okay. */
487 INET_CSUM_COUNTER_INCR(&ip_hwcsum_ok);
488 break;
489
490 default:
491 /* Must compute it ourselves. */
492 INET_CSUM_COUNTER_INCR(&ip_swcsum);
493 if (in_cksum(m, hlen) != 0)
494 goto bad;
495 break;
496 }
497
498 /* Retrieve the packet length. */
499 len = ntohs(ip->ip_len);
500
501 /*
502 * Check for additional length bogosity
503 */
504 if (len < hlen) {
505 ipstat.ips_badlen++;
506 goto bad;
507 }
508
509 /*
510 * Check that the amount of data in the buffers
511 * is as at least much as the IP header would have us expect.
512 * Trim mbufs if longer than we expect.
513 * Drop packet if shorter than we expect.
514 */
515 if (m->m_pkthdr.len < len) {
516 ipstat.ips_tooshort++;
517 goto bad;
518 }
519 if (m->m_pkthdr.len > len) {
520 if (m->m_len == m->m_pkthdr.len) {
521 m->m_len = len;
522 m->m_pkthdr.len = len;
523 } else
524 m_adj(m, len - m->m_pkthdr.len);
525 }
526
527 #ifdef IPSEC
528 /* ipflow (IP fast forwarding) is not compatible with IPsec. */
529 m->m_flags &= ~M_CANFASTFWD;
530 #else
531 /*
532 * Assume that we can create a fast-forward IP flow entry
533 * based on this packet.
534 */
535 m->m_flags |= M_CANFASTFWD;
536 #endif
537
538 #ifdef PFIL_HOOKS
539 /*
540 * Run through list of hooks for input packets. If there are any
541 * filters which require that additional packets in the flow are
542 * not fast-forwarded, they must clear the M_CANFASTFWD flag.
543 * Note that filters must _never_ set this flag, as another filter
544 * in the list may have previously cleared it.
545 */
546 /*
547 * let ipfilter look at packet on the wire,
548 * not the decapsulated packet.
549 */
550 #ifdef IPSEC
551 if (!ipsec_getnhist(m))
552 #else
553 if (1)
554 #endif
555 {
556 if (pfil_run_hooks(&inet_pfil_hook, &m, m->m_pkthdr.rcvif,
557 PFIL_IN) != 0)
558 return;
559 if (m == NULL)
560 return;
561 ip = mtod(m, struct ip *);
562 hlen = ip->ip_hl << 2;
563 }
564 #endif /* PFIL_HOOKS */
565
566 #ifdef ALTQ
567 /* XXX Temporary until ALTQ is changed to use a pfil hook */
568 if (altq_input != NULL && (*altq_input)(m, AF_INET) == 0) {
569 /* packet dropped by traffic conditioner */
570 return;
571 }
572 #endif
573
574 /*
575 * Process options and, if not destined for us,
576 * ship it on. ip_dooptions returns 1 when an
577 * error was detected (causing an icmp message
578 * to be sent and the original packet to be freed).
579 */
580 ip_nhops = 0; /* for source routed packets */
581 if (hlen > sizeof (struct ip) && ip_dooptions(m))
582 return;
583
584 /*
585 * Check our list of addresses, to see if the packet is for us.
586 *
587 * Traditional 4.4BSD did not consult IFF_UP at all.
588 * The behavior here is to treat addresses on !IFF_UP interface
589 * as not mine.
590 */
591 downmatch = 0;
592 LIST_FOREACH(ia, &IN_IFADDR_HASH(ip->ip_dst.s_addr), ia_hash) {
593 if (in_hosteq(ia->ia_addr.sin_addr, ip->ip_dst)) {
594 if ((ia->ia_ifp->if_flags & IFF_UP) != 0)
595 break;
596 else
597 downmatch++;
598 }
599 }
600 if (ia != NULL)
601 goto ours;
602 if (m->m_pkthdr.rcvif->if_flags & IFF_BROADCAST) {
603 TAILQ_FOREACH(ifa, &m->m_pkthdr.rcvif->if_addrlist, ifa_list) {
604 if (ifa->ifa_addr->sa_family != AF_INET)
605 continue;
606 ia = ifatoia(ifa);
607 if (in_hosteq(ip->ip_dst, ia->ia_broadaddr.sin_addr) ||
608 in_hosteq(ip->ip_dst, ia->ia_netbroadcast) ||
609 /*
610 * Look for all-0's host part (old broadcast addr),
611 * either for subnet or net.
612 */
613 ip->ip_dst.s_addr == ia->ia_subnet ||
614 ip->ip_dst.s_addr == ia->ia_net)
615 goto ours;
616 /*
617 * An interface with IP address zero accepts
618 * all packets that arrive on that interface.
619 */
620 if (in_nullhost(ia->ia_addr.sin_addr))
621 goto ours;
622 }
623 }
624 if (IN_MULTICAST(ip->ip_dst.s_addr)) {
625 struct in_multi *inm;
626 #ifdef MROUTING
627 extern struct socket *ip_mrouter;
628
629 if (M_READONLY(m)) {
630 if ((m = m_pullup(m, hlen)) == 0) {
631 ipstat.ips_toosmall++;
632 return;
633 }
634 ip = mtod(m, struct ip *);
635 }
636
637 if (ip_mrouter) {
638 /*
639 * If we are acting as a multicast router, all
640 * incoming multicast packets are passed to the
641 * kernel-level multicast forwarding function.
642 * The packet is returned (relatively) intact; if
643 * ip_mforward() returns a non-zero value, the packet
644 * must be discarded, else it may be accepted below.
645 *
646 * (The IP ident field is put in the same byte order
647 * as expected when ip_mforward() is called from
648 * ip_output().)
649 */
650 if (ip_mforward(m, m->m_pkthdr.rcvif) != 0) {
651 ipstat.ips_cantforward++;
652 m_freem(m);
653 return;
654 }
655
656 /*
657 * The process-level routing demon needs to receive
658 * all multicast IGMP packets, whether or not this
659 * host belongs to their destination groups.
660 */
661 if (ip->ip_p == IPPROTO_IGMP)
662 goto ours;
663 ipstat.ips_forward++;
664 }
665 #endif
666 /*
667 * See if we belong to the destination multicast group on the
668 * arrival interface.
669 */
670 IN_LOOKUP_MULTI(ip->ip_dst, m->m_pkthdr.rcvif, inm);
671 if (inm == NULL) {
672 ipstat.ips_cantforward++;
673 m_freem(m);
674 return;
675 }
676 goto ours;
677 }
678 if (ip->ip_dst.s_addr == INADDR_BROADCAST ||
679 in_nullhost(ip->ip_dst))
680 goto ours;
681
682 /*
683 * Not for us; forward if possible and desirable.
684 */
685 if (ipforwarding == 0) {
686 ipstat.ips_cantforward++;
687 m_freem(m);
688 } else {
689 /*
690 * If ip_dst matched any of my address on !IFF_UP interface,
691 * and there's no IFF_UP interface that matches ip_dst,
692 * send icmp unreach. Forwarding it will result in in-kernel
693 * forwarding loop till TTL goes to 0.
694 */
695 if (downmatch) {
696 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_HOST, 0, 0);
697 ipstat.ips_cantforward++;
698 return;
699 }
700 #ifdef IPSEC
701 if (ipsec4_in_reject(m, NULL)) {
702 ipsecstat.in_polvio++;
703 goto bad;
704 }
705 #endif
706
707 ip_forward(m, 0);
708 }
709 return;
710
711 ours:
712 /*
713 * If offset or IP_MF are set, must reassemble.
714 * Otherwise, nothing need be done.
715 * (We could look in the reassembly queue to see
716 * if the packet was previously fragmented,
717 * but it's not worth the time; just let them time out.)
718 */
719 if (ip->ip_off & ~htons(IP_DF|IP_RF)) {
720 if (M_READONLY(m)) {
721 if ((m = m_pullup(m, hlen)) == NULL) {
722 ipstat.ips_toosmall++;
723 goto bad;
724 }
725 ip = mtod(m, struct ip *);
726 }
727
728 /*
729 * Look for queue of fragments
730 * of this datagram.
731 */
732 IPQ_LOCK();
733 LIST_FOREACH(fp, &ipq, ipq_q)
734 if (ip->ip_id == fp->ipq_id &&
735 in_hosteq(ip->ip_src, fp->ipq_src) &&
736 in_hosteq(ip->ip_dst, fp->ipq_dst) &&
737 ip->ip_p == fp->ipq_p)
738 goto found;
739 fp = 0;
740 found:
741
742 /*
743 * Adjust ip_len to not reflect header,
744 * set ipqe_mff if more fragments are expected,
745 * convert offset of this to bytes.
746 */
747 ip->ip_len = htons(ntohs(ip->ip_len) - hlen);
748 mff = (ip->ip_off & htons(IP_MF)) != 0;
749 if (mff) {
750 /*
751 * Make sure that fragments have a data length
752 * that's a non-zero multiple of 8 bytes.
753 */
754 if (ntohs(ip->ip_len) == 0 ||
755 (ntohs(ip->ip_len) & 0x7) != 0) {
756 ipstat.ips_badfrags++;
757 IPQ_UNLOCK();
758 goto bad;
759 }
760 }
761 ip->ip_off = htons((ntohs(ip->ip_off) & IP_OFFMASK) << 3);
762
763 /*
764 * If datagram marked as having more fragments
765 * or if this is not the first fragment,
766 * attempt reassembly; if it succeeds, proceed.
767 */
768 if (mff || ip->ip_off != htons(0)) {
769 ipstat.ips_fragments++;
770 ipqe = pool_get(&ipqent_pool, PR_NOWAIT);
771 if (ipqe == NULL) {
772 ipstat.ips_rcvmemdrop++;
773 IPQ_UNLOCK();
774 goto bad;
775 }
776 ipqe->ipqe_mff = mff;
777 ipqe->ipqe_m = m;
778 ipqe->ipqe_ip = ip;
779 m = ip_reass(ipqe, fp);
780 if (m == 0) {
781 IPQ_UNLOCK();
782 return;
783 }
784 ipstat.ips_reassembled++;
785 ip = mtod(m, struct ip *);
786 hlen = ip->ip_hl << 2;
787 ip->ip_len = htons(ntohs(ip->ip_len) + hlen);
788 } else
789 if (fp)
790 ip_freef(fp);
791 IPQ_UNLOCK();
792 }
793
794 #ifdef IPSEC
795 /*
796 * enforce IPsec policy checking if we are seeing last header.
797 * note that we do not visit this with protocols with pcb layer
798 * code - like udp/tcp/raw ip.
799 */
800 if ((inetsw[ip_protox[ip->ip_p]].pr_flags & PR_LASTHDR) != 0 &&
801 ipsec4_in_reject(m, NULL)) {
802 ipsecstat.in_polvio++;
803 goto bad;
804 }
805 #endif
806
807 /*
808 * Switch out to protocol's input routine.
809 */
810 #if IFA_STATS
811 if (ia && ip)
812 ia->ia_ifa.ifa_data.ifad_inbytes += ntohs(ip->ip_len);
813 #endif
814 ipstat.ips_delivered++;
815 {
816 int off = hlen, nh = ip->ip_p;
817
818 (*inetsw[ip_protox[nh]].pr_input)(m, off, nh);
819 return;
820 }
821 bad:
822 m_freem(m);
823 return;
824
825 badcsum:
826 ipstat.ips_badsum++;
827 m_freem(m);
828 }
829
830 /*
831 * Take incoming datagram fragment and try to
832 * reassemble it into whole datagram. If a chain for
833 * reassembly of this datagram already exists, then it
834 * is given as fp; otherwise have to make a chain.
835 */
836 struct mbuf *
837 ip_reass(ipqe, fp)
838 struct ipqent *ipqe;
839 struct ipq *fp;
840 {
841 struct mbuf *m = ipqe->ipqe_m;
842 struct ipqent *nq, *p, *q;
843 struct ip *ip;
844 struct mbuf *t;
845 int hlen = ipqe->ipqe_ip->ip_hl << 2;
846 int i, next;
847
848 IPQ_LOCK_CHECK();
849
850 /*
851 * Presence of header sizes in mbufs
852 * would confuse code below.
853 */
854 m->m_data += hlen;
855 m->m_len -= hlen;
856
857 /*
858 * If first fragment to arrive, create a reassembly queue.
859 */
860 if (fp == 0) {
861 /*
862 * Enforce upper bound on number of fragmented packets
863 * for which we attempt reassembly;
864 * If maxfrag is 0, never accept fragments.
865 * If maxfrag is -1, accept all fragments without limitation.
866 */
867 if (ip_maxfragpackets < 0)
868 ;
869 else if (ip_nfragpackets >= ip_maxfragpackets)
870 goto dropfrag;
871 ip_nfragpackets++;
872 MALLOC(fp, struct ipq *, sizeof (struct ipq),
873 M_FTABLE, M_NOWAIT);
874 if (fp == NULL)
875 goto dropfrag;
876 LIST_INSERT_HEAD(&ipq, fp, ipq_q);
877 fp->ipq_ttl = IPFRAGTTL;
878 fp->ipq_p = ipqe->ipqe_ip->ip_p;
879 fp->ipq_id = ipqe->ipqe_ip->ip_id;
880 TAILQ_INIT(&fp->ipq_fragq);
881 fp->ipq_src = ipqe->ipqe_ip->ip_src;
882 fp->ipq_dst = ipqe->ipqe_ip->ip_dst;
883 p = NULL;
884 goto insert;
885 }
886
887 /*
888 * Find a segment which begins after this one does.
889 */
890 for (p = NULL, q = TAILQ_FIRST(&fp->ipq_fragq); q != NULL;
891 p = q, q = TAILQ_NEXT(q, ipqe_q))
892 if (ntohs(q->ipqe_ip->ip_off) > ntohs(ipqe->ipqe_ip->ip_off))
893 break;
894
895 /*
896 * If there is a preceding segment, it may provide some of
897 * our data already. If so, drop the data from the incoming
898 * segment. If it provides all of our data, drop us.
899 */
900 if (p != NULL) {
901 i = ntohs(p->ipqe_ip->ip_off) + ntohs(p->ipqe_ip->ip_len) -
902 ntohs(ipqe->ipqe_ip->ip_off);
903 if (i > 0) {
904 if (i >= ntohs(ipqe->ipqe_ip->ip_len))
905 goto dropfrag;
906 m_adj(ipqe->ipqe_m, i);
907 ipqe->ipqe_ip->ip_off =
908 htons(ntohs(ipqe->ipqe_ip->ip_off) + i);
909 ipqe->ipqe_ip->ip_len =
910 htons(ntohs(ipqe->ipqe_ip->ip_len) - i);
911 }
912 }
913
914 /*
915 * While we overlap succeeding segments trim them or,
916 * if they are completely covered, dequeue them.
917 */
918 for (; q != NULL &&
919 ntohs(ipqe->ipqe_ip->ip_off) + ntohs(ipqe->ipqe_ip->ip_len) >
920 ntohs(q->ipqe_ip->ip_off); q = nq) {
921 i = (ntohs(ipqe->ipqe_ip->ip_off) +
922 ntohs(ipqe->ipqe_ip->ip_len)) - ntohs(q->ipqe_ip->ip_off);
923 if (i < ntohs(q->ipqe_ip->ip_len)) {
924 q->ipqe_ip->ip_len =
925 htons(ntohs(q->ipqe_ip->ip_len) - i);
926 q->ipqe_ip->ip_off =
927 htons(ntohs(q->ipqe_ip->ip_off) + i);
928 m_adj(q->ipqe_m, i);
929 break;
930 }
931 nq = TAILQ_NEXT(q, ipqe_q);
932 m_freem(q->ipqe_m);
933 TAILQ_REMOVE(&fp->ipq_fragq, q, ipqe_q);
934 pool_put(&ipqent_pool, q);
935 }
936
937 insert:
938 /*
939 * Stick new segment in its place;
940 * check for complete reassembly.
941 */
942 if (p == NULL) {
943 TAILQ_INSERT_HEAD(&fp->ipq_fragq, ipqe, ipqe_q);
944 } else {
945 TAILQ_INSERT_AFTER(&fp->ipq_fragq, p, ipqe, ipqe_q);
946 }
947 next = 0;
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) != next)
951 return (0);
952 next += ntohs(q->ipqe_ip->ip_len);
953 }
954 if (p->ipqe_mff)
955 return (0);
956
957 /*
958 * Reassembly is complete. Check for a bogus message size and
959 * concatenate fragments.
960 */
961 q = TAILQ_FIRST(&fp->ipq_fragq);
962 ip = q->ipqe_ip;
963 if ((next + (ip->ip_hl << 2)) > IP_MAXPACKET) {
964 ipstat.ips_toolong++;
965 ip_freef(fp);
966 return (0);
967 }
968 m = q->ipqe_m;
969 t = m->m_next;
970 m->m_next = 0;
971 m_cat(m, t);
972 nq = TAILQ_NEXT(q, ipqe_q);
973 pool_put(&ipqent_pool, q);
974 for (q = nq; q != NULL; q = nq) {
975 t = q->ipqe_m;
976 nq = TAILQ_NEXT(q, ipqe_q);
977 pool_put(&ipqent_pool, q);
978 m_cat(m, t);
979 }
980
981 /*
982 * Create header for new ip packet by
983 * modifying header of first packet;
984 * dequeue and discard fragment reassembly header.
985 * Make header visible.
986 */
987 ip->ip_len = htons(next);
988 ip->ip_src = fp->ipq_src;
989 ip->ip_dst = fp->ipq_dst;
990 LIST_REMOVE(fp, ipq_q);
991 FREE(fp, M_FTABLE);
992 ip_nfragpackets--;
993 m->m_len += (ip->ip_hl << 2);
994 m->m_data -= (ip->ip_hl << 2);
995 /* some debugging cruft by sklower, below, will go away soon */
996 if (m->m_flags & M_PKTHDR) { /* XXX this should be done elsewhere */
997 int plen = 0;
998 for (t = m; t; t = t->m_next)
999 plen += t->m_len;
1000 m->m_pkthdr.len = plen;
1001 }
1002 return (m);
1003
1004 dropfrag:
1005 ipstat.ips_fragdropped++;
1006 m_freem(m);
1007 pool_put(&ipqent_pool, ipqe);
1008 return (0);
1009 }
1010
1011 /*
1012 * Free a fragment reassembly header and all
1013 * associated datagrams.
1014 */
1015 void
1016 ip_freef(fp)
1017 struct ipq *fp;
1018 {
1019 struct ipqent *q, *p;
1020
1021 IPQ_LOCK_CHECK();
1022
1023 for (q = TAILQ_FIRST(&fp->ipq_fragq); q != NULL; q = p) {
1024 p = TAILQ_NEXT(q, ipqe_q);
1025 m_freem(q->ipqe_m);
1026 TAILQ_REMOVE(&fp->ipq_fragq, q, ipqe_q);
1027 pool_put(&ipqent_pool, q);
1028 }
1029 LIST_REMOVE(fp, ipq_q);
1030 FREE(fp, M_FTABLE);
1031 ip_nfragpackets--;
1032 }
1033
1034 /*
1035 * IP timer processing;
1036 * if a timer expires on a reassembly
1037 * queue, discard it.
1038 */
1039 void
1040 ip_slowtimo()
1041 {
1042 struct ipq *fp, *nfp;
1043 int s = splsoftnet();
1044
1045 IPQ_LOCK();
1046 for (fp = LIST_FIRST(&ipq); fp != NULL; fp = nfp) {
1047 nfp = LIST_NEXT(fp, ipq_q);
1048 if (--fp->ipq_ttl == 0) {
1049 ipstat.ips_fragtimeout++;
1050 ip_freef(fp);
1051 }
1052 }
1053 /*
1054 * If we are over the maximum number of fragments
1055 * (due to the limit being lowered), drain off
1056 * enough to get down to the new limit.
1057 */
1058 if (ip_maxfragpackets < 0)
1059 ;
1060 else {
1061 while (ip_nfragpackets > ip_maxfragpackets && LIST_FIRST(&ipq))
1062 ip_freef(LIST_FIRST(&ipq));
1063 }
1064 IPQ_UNLOCK();
1065 #ifdef GATEWAY
1066 ipflow_slowtimo();
1067 #endif
1068 splx(s);
1069 }
1070
1071 /*
1072 * Drain off all datagram fragments.
1073 */
1074 void
1075 ip_drain()
1076 {
1077
1078 /*
1079 * We may be called from a device's interrupt context. If
1080 * the ipq is already busy, just bail out now.
1081 */
1082 if (ipq_lock_try() == 0)
1083 return;
1084
1085 while (LIST_FIRST(&ipq) != NULL) {
1086 ipstat.ips_fragdropped++;
1087 ip_freef(LIST_FIRST(&ipq));
1088 }
1089
1090 IPQ_UNLOCK();
1091 }
1092
1093 /*
1094 * Do option processing on a datagram,
1095 * possibly discarding it if bad options are encountered,
1096 * or forwarding it if source-routed.
1097 * Returns 1 if packet has been forwarded/freed,
1098 * 0 if the packet should be processed further.
1099 */
1100 int
1101 ip_dooptions(m)
1102 struct mbuf *m;
1103 {
1104 struct ip *ip = mtod(m, struct ip *);
1105 u_char *cp, *cp0;
1106 struct ip_timestamp *ipt;
1107 struct in_ifaddr *ia;
1108 int opt, optlen, cnt, off, code, type = ICMP_PARAMPROB, forward = 0;
1109 struct in_addr dst;
1110 n_time ntime;
1111
1112 dst = ip->ip_dst;
1113 cp = (u_char *)(ip + 1);
1114 cnt = (ip->ip_hl << 2) - sizeof (struct ip);
1115 for (; cnt > 0; cnt -= optlen, cp += optlen) {
1116 opt = cp[IPOPT_OPTVAL];
1117 if (opt == IPOPT_EOL)
1118 break;
1119 if (opt == IPOPT_NOP)
1120 optlen = 1;
1121 else {
1122 if (cnt < IPOPT_OLEN + sizeof(*cp)) {
1123 code = &cp[IPOPT_OLEN] - (u_char *)ip;
1124 goto bad;
1125 }
1126 optlen = cp[IPOPT_OLEN];
1127 if (optlen < IPOPT_OLEN + sizeof(*cp) || optlen > cnt) {
1128 code = &cp[IPOPT_OLEN] - (u_char *)ip;
1129 goto bad;
1130 }
1131 }
1132 switch (opt) {
1133
1134 default:
1135 break;
1136
1137 /*
1138 * Source routing with record.
1139 * Find interface with current destination address.
1140 * If none on this machine then drop if strictly routed,
1141 * or do nothing if loosely routed.
1142 * Record interface address and bring up next address
1143 * component. If strictly routed make sure next
1144 * address is on directly accessible net.
1145 */
1146 case IPOPT_LSRR:
1147 case IPOPT_SSRR:
1148 if (ip_allowsrcrt == 0) {
1149 type = ICMP_UNREACH;
1150 code = ICMP_UNREACH_NET_PROHIB;
1151 goto bad;
1152 }
1153 if (optlen < IPOPT_OFFSET + sizeof(*cp)) {
1154 code = &cp[IPOPT_OLEN] - (u_char *)ip;
1155 goto bad;
1156 }
1157 if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) {
1158 code = &cp[IPOPT_OFFSET] - (u_char *)ip;
1159 goto bad;
1160 }
1161 ipaddr.sin_addr = ip->ip_dst;
1162 ia = ifatoia(ifa_ifwithaddr(sintosa(&ipaddr)));
1163 if (ia == 0) {
1164 if (opt == IPOPT_SSRR) {
1165 type = ICMP_UNREACH;
1166 code = ICMP_UNREACH_SRCFAIL;
1167 goto bad;
1168 }
1169 /*
1170 * Loose routing, and not at next destination
1171 * yet; nothing to do except forward.
1172 */
1173 break;
1174 }
1175 off--; /* 0 origin */
1176 if ((off + sizeof(struct in_addr)) > optlen) {
1177 /*
1178 * End of source route. Should be for us.
1179 */
1180 save_rte(cp, ip->ip_src);
1181 break;
1182 }
1183 /*
1184 * locate outgoing interface
1185 */
1186 bcopy((caddr_t)(cp + off), (caddr_t)&ipaddr.sin_addr,
1187 sizeof(ipaddr.sin_addr));
1188 if (opt == IPOPT_SSRR)
1189 ia = ifatoia(ifa_ifwithaddr(sintosa(&ipaddr)));
1190 else
1191 ia = ip_rtaddr(ipaddr.sin_addr);
1192 if (ia == 0) {
1193 type = ICMP_UNREACH;
1194 code = ICMP_UNREACH_SRCFAIL;
1195 goto bad;
1196 }
1197 ip->ip_dst = ipaddr.sin_addr;
1198 bcopy((caddr_t)&ia->ia_addr.sin_addr,
1199 (caddr_t)(cp + off), sizeof(struct in_addr));
1200 cp[IPOPT_OFFSET] += sizeof(struct in_addr);
1201 /*
1202 * Let ip_intr's mcast routing check handle mcast pkts
1203 */
1204 forward = !IN_MULTICAST(ip->ip_dst.s_addr);
1205 break;
1206
1207 case IPOPT_RR:
1208 if (optlen < IPOPT_OFFSET + sizeof(*cp)) {
1209 code = &cp[IPOPT_OLEN] - (u_char *)ip;
1210 goto bad;
1211 }
1212 if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) {
1213 code = &cp[IPOPT_OFFSET] - (u_char *)ip;
1214 goto bad;
1215 }
1216 /*
1217 * If no space remains, ignore.
1218 */
1219 off--; /* 0 origin */
1220 if ((off + sizeof(struct in_addr)) > optlen)
1221 break;
1222 bcopy((caddr_t)(&ip->ip_dst), (caddr_t)&ipaddr.sin_addr,
1223 sizeof(ipaddr.sin_addr));
1224 /*
1225 * locate outgoing interface; if we're the destination,
1226 * use the incoming interface (should be same).
1227 */
1228 if ((ia = ifatoia(ifa_ifwithaddr(sintosa(&ipaddr))))
1229 == NULL &&
1230 (ia = ip_rtaddr(ipaddr.sin_addr)) == NULL) {
1231 type = ICMP_UNREACH;
1232 code = ICMP_UNREACH_HOST;
1233 goto bad;
1234 }
1235 bcopy((caddr_t)&ia->ia_addr.sin_addr,
1236 (caddr_t)(cp + off), sizeof(struct in_addr));
1237 cp[IPOPT_OFFSET] += sizeof(struct in_addr);
1238 break;
1239
1240 case IPOPT_TS:
1241 code = cp - (u_char *)ip;
1242 ipt = (struct ip_timestamp *)cp;
1243 if (ipt->ipt_len < 4 || ipt->ipt_len > 40) {
1244 code = (u_char *)&ipt->ipt_len - (u_char *)ip;
1245 goto bad;
1246 }
1247 if (ipt->ipt_ptr < 5) {
1248 code = (u_char *)&ipt->ipt_ptr - (u_char *)ip;
1249 goto bad;
1250 }
1251 if (ipt->ipt_ptr > ipt->ipt_len - sizeof (int32_t)) {
1252 if (++ipt->ipt_oflw == 0) {
1253 code = (u_char *)&ipt->ipt_ptr -
1254 (u_char *)ip;
1255 goto bad;
1256 }
1257 break;
1258 }
1259 cp0 = (cp + ipt->ipt_ptr - 1);
1260 switch (ipt->ipt_flg) {
1261
1262 case IPOPT_TS_TSONLY:
1263 break;
1264
1265 case IPOPT_TS_TSANDADDR:
1266 if (ipt->ipt_ptr - 1 + sizeof(n_time) +
1267 sizeof(struct in_addr) > ipt->ipt_len) {
1268 code = (u_char *)&ipt->ipt_ptr -
1269 (u_char *)ip;
1270 goto bad;
1271 }
1272 ipaddr.sin_addr = dst;
1273 ia = ifatoia(ifaof_ifpforaddr(sintosa(&ipaddr),
1274 m->m_pkthdr.rcvif));
1275 if (ia == 0)
1276 continue;
1277 bcopy(&ia->ia_addr.sin_addr,
1278 cp0, sizeof(struct in_addr));
1279 ipt->ipt_ptr += sizeof(struct in_addr);
1280 break;
1281
1282 case IPOPT_TS_PRESPEC:
1283 if (ipt->ipt_ptr - 1 + sizeof(n_time) +
1284 sizeof(struct in_addr) > ipt->ipt_len) {
1285 code = (u_char *)&ipt->ipt_ptr -
1286 (u_char *)ip;
1287 goto bad;
1288 }
1289 bcopy(cp0, &ipaddr.sin_addr,
1290 sizeof(struct in_addr));
1291 if (ifatoia(ifa_ifwithaddr(sintosa(&ipaddr)))
1292 == NULL)
1293 continue;
1294 ipt->ipt_ptr += sizeof(struct in_addr);
1295 break;
1296
1297 default:
1298 /* XXX can't take &ipt->ipt_flg */
1299 code = (u_char *)&ipt->ipt_ptr -
1300 (u_char *)ip + 1;
1301 goto bad;
1302 }
1303 ntime = iptime();
1304 cp0 = (u_char *) &ntime; /* XXX grumble, GCC... */
1305 bcopy(cp0, (caddr_t)cp + ipt->ipt_ptr - 1,
1306 sizeof(n_time));
1307 ipt->ipt_ptr += sizeof(n_time);
1308 }
1309 }
1310 if (forward) {
1311 if (ip_forwsrcrt == 0) {
1312 type = ICMP_UNREACH;
1313 code = ICMP_UNREACH_SRCFAIL;
1314 goto bad;
1315 }
1316 ip_forward(m, 1);
1317 return (1);
1318 }
1319 return (0);
1320 bad:
1321 icmp_error(m, type, code, 0, 0);
1322 ipstat.ips_badoptions++;
1323 return (1);
1324 }
1325
1326 /*
1327 * Given address of next destination (final or next hop),
1328 * return internet address info of interface to be used to get there.
1329 */
1330 struct in_ifaddr *
1331 ip_rtaddr(dst)
1332 struct in_addr dst;
1333 {
1334 struct sockaddr_in *sin;
1335
1336 sin = satosin(&ipforward_rt.ro_dst);
1337
1338 if (ipforward_rt.ro_rt == 0 || !in_hosteq(dst, sin->sin_addr)) {
1339 if (ipforward_rt.ro_rt) {
1340 RTFREE(ipforward_rt.ro_rt);
1341 ipforward_rt.ro_rt = 0;
1342 }
1343 sin->sin_family = AF_INET;
1344 sin->sin_len = sizeof(*sin);
1345 sin->sin_addr = dst;
1346
1347 rtalloc(&ipforward_rt);
1348 }
1349 if (ipforward_rt.ro_rt == 0)
1350 return ((struct in_ifaddr *)0);
1351 return (ifatoia(ipforward_rt.ro_rt->rt_ifa));
1352 }
1353
1354 /*
1355 * Save incoming source route for use in replies,
1356 * to be picked up later by ip_srcroute if the receiver is interested.
1357 */
1358 void
1359 save_rte(option, dst)
1360 u_char *option;
1361 struct in_addr dst;
1362 {
1363 unsigned olen;
1364
1365 olen = option[IPOPT_OLEN];
1366 #ifdef DIAGNOSTIC
1367 if (ipprintfs)
1368 printf("save_rte: olen %d\n", olen);
1369 #endif /* 0 */
1370 if (olen > sizeof(ip_srcrt) - (1 + sizeof(dst)))
1371 return;
1372 bcopy((caddr_t)option, (caddr_t)ip_srcrt.srcopt, olen);
1373 ip_nhops = (olen - IPOPT_OFFSET - 1) / sizeof(struct in_addr);
1374 ip_srcrt.dst = dst;
1375 }
1376
1377 /*
1378 * Retrieve incoming source route for use in replies,
1379 * in the same form used by setsockopt.
1380 * The first hop is placed before the options, will be removed later.
1381 */
1382 struct mbuf *
1383 ip_srcroute()
1384 {
1385 struct in_addr *p, *q;
1386 struct mbuf *m;
1387
1388 if (ip_nhops == 0)
1389 return ((struct mbuf *)0);
1390 m = m_get(M_DONTWAIT, MT_SOOPTS);
1391 if (m == 0)
1392 return ((struct mbuf *)0);
1393
1394 #define OPTSIZ (sizeof(ip_srcrt.nop) + sizeof(ip_srcrt.srcopt))
1395
1396 /* length is (nhops+1)*sizeof(addr) + sizeof(nop + srcrt header) */
1397 m->m_len = ip_nhops * sizeof(struct in_addr) + sizeof(struct in_addr) +
1398 OPTSIZ;
1399 #ifdef DIAGNOSTIC
1400 if (ipprintfs)
1401 printf("ip_srcroute: nhops %d mlen %d", ip_nhops, m->m_len);
1402 #endif
1403
1404 /*
1405 * First save first hop for return route
1406 */
1407 p = &ip_srcrt.route[ip_nhops - 1];
1408 *(mtod(m, struct in_addr *)) = *p--;
1409 #ifdef DIAGNOSTIC
1410 if (ipprintfs)
1411 printf(" hops %x", ntohl(mtod(m, struct in_addr *)->s_addr));
1412 #endif
1413
1414 /*
1415 * Copy option fields and padding (nop) to mbuf.
1416 */
1417 ip_srcrt.nop = IPOPT_NOP;
1418 ip_srcrt.srcopt[IPOPT_OFFSET] = IPOPT_MINOFF;
1419 bcopy((caddr_t)&ip_srcrt.nop,
1420 mtod(m, caddr_t) + sizeof(struct in_addr), OPTSIZ);
1421 q = (struct in_addr *)(mtod(m, caddr_t) +
1422 sizeof(struct in_addr) + OPTSIZ);
1423 #undef OPTSIZ
1424 /*
1425 * Record return path as an IP source route,
1426 * reversing the path (pointers are now aligned).
1427 */
1428 while (p >= ip_srcrt.route) {
1429 #ifdef DIAGNOSTIC
1430 if (ipprintfs)
1431 printf(" %x", ntohl(q->s_addr));
1432 #endif
1433 *q++ = *p--;
1434 }
1435 /*
1436 * Last hop goes to final destination.
1437 */
1438 *q = ip_srcrt.dst;
1439 #ifdef DIAGNOSTIC
1440 if (ipprintfs)
1441 printf(" %x\n", ntohl(q->s_addr));
1442 #endif
1443 return (m);
1444 }
1445
1446 /*
1447 * Strip out IP options, at higher
1448 * level protocol in the kernel.
1449 * Second argument is buffer to which options
1450 * will be moved, and return value is their length.
1451 * XXX should be deleted; last arg currently ignored.
1452 */
1453 void
1454 ip_stripoptions(m, mopt)
1455 struct mbuf *m;
1456 struct mbuf *mopt;
1457 {
1458 int i;
1459 struct ip *ip = mtod(m, struct ip *);
1460 caddr_t opts;
1461 int olen;
1462
1463 olen = (ip->ip_hl << 2) - sizeof (struct ip);
1464 opts = (caddr_t)(ip + 1);
1465 i = m->m_len - (sizeof (struct ip) + olen);
1466 bcopy(opts + olen, opts, (unsigned)i);
1467 m->m_len -= olen;
1468 if (m->m_flags & M_PKTHDR)
1469 m->m_pkthdr.len -= olen;
1470 ip->ip_len = htons(ntohs(ip->ip_len) - olen);
1471 ip->ip_hl = sizeof (struct ip) >> 2;
1472 }
1473
1474 const int inetctlerrmap[PRC_NCMDS] = {
1475 0, 0, 0, 0,
1476 0, EMSGSIZE, EHOSTDOWN, EHOSTUNREACH,
1477 EHOSTUNREACH, EHOSTUNREACH, ECONNREFUSED, ECONNREFUSED,
1478 EMSGSIZE, EHOSTUNREACH, 0, 0,
1479 0, 0, 0, 0,
1480 ENOPROTOOPT
1481 };
1482
1483 /*
1484 * Forward a packet. If some error occurs return the sender
1485 * an icmp packet. Note we can't always generate a meaningful
1486 * icmp message because icmp doesn't have a large enough repertoire
1487 * of codes and types.
1488 *
1489 * If not forwarding, just drop the packet. This could be confusing
1490 * if ipforwarding was zero but some routing protocol was advancing
1491 * us as a gateway to somewhere. However, we must let the routing
1492 * protocol deal with that.
1493 *
1494 * The srcrt parameter indicates whether the packet is being forwarded
1495 * via a source route.
1496 */
1497 void
1498 ip_forward(m, srcrt)
1499 struct mbuf *m;
1500 int srcrt;
1501 {
1502 struct ip *ip = mtod(m, struct ip *);
1503 struct sockaddr_in *sin;
1504 struct rtentry *rt;
1505 int error, type = 0, code = 0;
1506 struct mbuf *mcopy;
1507 n_long dest;
1508 struct ifnet *destifp;
1509 #ifdef IPSEC
1510 struct ifnet dummyifp;
1511 #endif
1512
1513 /*
1514 * Clear any in-bound checksum flags for this packet.
1515 */
1516 m->m_pkthdr.csum_flags = 0;
1517
1518 dest = 0;
1519 #ifdef DIAGNOSTIC
1520 if (ipprintfs)
1521 printf("forward: src %2.2x dst %2.2x ttl %x\n",
1522 ntohl(ip->ip_src.s_addr),
1523 ntohl(ip->ip_dst.s_addr), ip->ip_ttl);
1524 #endif
1525 if (m->m_flags & (M_BCAST|M_MCAST) || in_canforward(ip->ip_dst) == 0) {
1526 ipstat.ips_cantforward++;
1527 m_freem(m);
1528 return;
1529 }
1530 if (ip->ip_ttl <= IPTTLDEC) {
1531 icmp_error(m, ICMP_TIMXCEED, ICMP_TIMXCEED_INTRANS, dest, 0);
1532 return;
1533 }
1534 ip->ip_ttl -= IPTTLDEC;
1535
1536 sin = satosin(&ipforward_rt.ro_dst);
1537 if ((rt = ipforward_rt.ro_rt) == 0 ||
1538 !in_hosteq(ip->ip_dst, sin->sin_addr)) {
1539 if (ipforward_rt.ro_rt) {
1540 RTFREE(ipforward_rt.ro_rt);
1541 ipforward_rt.ro_rt = 0;
1542 }
1543 sin->sin_family = AF_INET;
1544 sin->sin_len = sizeof(struct sockaddr_in);
1545 sin->sin_addr = ip->ip_dst;
1546
1547 rtalloc(&ipforward_rt);
1548 if (ipforward_rt.ro_rt == 0) {
1549 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_HOST, dest, 0);
1550 return;
1551 }
1552 rt = ipforward_rt.ro_rt;
1553 }
1554
1555 /*
1556 * Save at most 68 bytes of the packet in case
1557 * we need to generate an ICMP message to the src.
1558 * Pullup to avoid sharing mbuf cluster between m and mcopy.
1559 */
1560 mcopy = m_copym(m, 0, imin(ntohs(ip->ip_len), 68), M_DONTWAIT);
1561 if (mcopy)
1562 mcopy = m_pullup(mcopy, ip->ip_hl << 2);
1563
1564 /*
1565 * If forwarding packet using same interface that it came in on,
1566 * perhaps should send a redirect to sender to shortcut a hop.
1567 * Only send redirect if source is sending directly to us,
1568 * and if packet was not source routed (or has any options).
1569 * Also, don't send redirect if forwarding using a default route
1570 * or a route modified by a redirect.
1571 */
1572 if (rt->rt_ifp == m->m_pkthdr.rcvif &&
1573 (rt->rt_flags & (RTF_DYNAMIC|RTF_MODIFIED)) == 0 &&
1574 !in_nullhost(satosin(rt_key(rt))->sin_addr) &&
1575 ipsendredirects && !srcrt) {
1576 if (rt->rt_ifa &&
1577 (ip->ip_src.s_addr & ifatoia(rt->rt_ifa)->ia_subnetmask) ==
1578 ifatoia(rt->rt_ifa)->ia_subnet) {
1579 if (rt->rt_flags & RTF_GATEWAY)
1580 dest = satosin(rt->rt_gateway)->sin_addr.s_addr;
1581 else
1582 dest = ip->ip_dst.s_addr;
1583 /*
1584 * Router requirements says to only send host
1585 * redirects.
1586 */
1587 type = ICMP_REDIRECT;
1588 code = ICMP_REDIRECT_HOST;
1589 #ifdef DIAGNOSTIC
1590 if (ipprintfs)
1591 printf("redirect (%d) to %x\n", code,
1592 (u_int32_t)dest);
1593 #endif
1594 }
1595 }
1596
1597 #ifdef IPSEC
1598 /* Don't lookup socket in forwarding case */
1599 (void)ipsec_setsocket(m, NULL);
1600 #endif
1601 error = ip_output(m, (struct mbuf *)0, &ipforward_rt,
1602 (IP_FORWARDING | (ip_directedbcast ? IP_ALLOWBROADCAST : 0)), 0);
1603 if (error)
1604 ipstat.ips_cantforward++;
1605 else {
1606 ipstat.ips_forward++;
1607 if (type)
1608 ipstat.ips_redirectsent++;
1609 else {
1610 if (mcopy) {
1611 #ifdef GATEWAY
1612 if (mcopy->m_flags & M_CANFASTFWD)
1613 ipflow_create(&ipforward_rt, mcopy);
1614 #endif
1615 m_freem(mcopy);
1616 }
1617 return;
1618 }
1619 }
1620 if (mcopy == NULL)
1621 return;
1622 destifp = NULL;
1623
1624 switch (error) {
1625
1626 case 0: /* forwarded, but need redirect */
1627 /* type, code set above */
1628 break;
1629
1630 case ENETUNREACH: /* shouldn't happen, checked above */
1631 case EHOSTUNREACH:
1632 case ENETDOWN:
1633 case EHOSTDOWN:
1634 default:
1635 type = ICMP_UNREACH;
1636 code = ICMP_UNREACH_HOST;
1637 break;
1638
1639 case EMSGSIZE:
1640 type = ICMP_UNREACH;
1641 code = ICMP_UNREACH_NEEDFRAG;
1642 #ifndef IPSEC
1643 if (ipforward_rt.ro_rt)
1644 destifp = ipforward_rt.ro_rt->rt_ifp;
1645 #else
1646 /*
1647 * If the packet is routed over IPsec tunnel, tell the
1648 * originator the tunnel MTU.
1649 * tunnel MTU = if MTU - sizeof(IP) - ESP/AH hdrsiz
1650 * XXX quickhack!!!
1651 */
1652 if (ipforward_rt.ro_rt) {
1653 struct secpolicy *sp;
1654 int ipsecerror;
1655 size_t ipsechdr;
1656 struct route *ro;
1657
1658 sp = ipsec4_getpolicybyaddr(mcopy,
1659 IPSEC_DIR_OUTBOUND,
1660 IP_FORWARDING,
1661 &ipsecerror);
1662
1663 if (sp == NULL)
1664 destifp = ipforward_rt.ro_rt->rt_ifp;
1665 else {
1666 /* count IPsec header size */
1667 ipsechdr = ipsec4_hdrsiz(mcopy,
1668 IPSEC_DIR_OUTBOUND,
1669 NULL);
1670
1671 /*
1672 * find the correct route for outer IPv4
1673 * header, compute tunnel MTU.
1674 *
1675 * XXX BUG ALERT
1676 * The "dummyifp" code relies upon the fact
1677 * that icmp_error() touches only ifp->if_mtu.
1678 */
1679 /*XXX*/
1680 destifp = NULL;
1681 if (sp->req != NULL
1682 && sp->req->sav != NULL
1683 && sp->req->sav->sah != NULL) {
1684 ro = &sp->req->sav->sah->sa_route;
1685 if (ro->ro_rt && ro->ro_rt->rt_ifp) {
1686 dummyifp.if_mtu =
1687 ro->ro_rt->rt_rmx.rmx_mtu ?
1688 ro->ro_rt->rt_rmx.rmx_mtu :
1689 ro->ro_rt->rt_ifp->if_mtu;
1690 dummyifp.if_mtu -= ipsechdr;
1691 destifp = &dummyifp;
1692 }
1693 }
1694
1695 key_freesp(sp);
1696 }
1697 }
1698 #endif /*IPSEC*/
1699 ipstat.ips_cantfrag++;
1700 break;
1701
1702 case ENOBUFS:
1703 #if 1
1704 /*
1705 * a router should not generate ICMP_SOURCEQUENCH as
1706 * required in RFC1812 Requirements for IP Version 4 Routers.
1707 * source quench could be a big problem under DoS attacks,
1708 * or if the underlying interface is rate-limited.
1709 */
1710 if (mcopy)
1711 m_freem(mcopy);
1712 return;
1713 #else
1714 type = ICMP_SOURCEQUENCH;
1715 code = 0;
1716 break;
1717 #endif
1718 }
1719 icmp_error(mcopy, type, code, dest, destifp);
1720 }
1721
1722 void
1723 ip_savecontrol(inp, mp, ip, m)
1724 struct inpcb *inp;
1725 struct mbuf **mp;
1726 struct ip *ip;
1727 struct mbuf *m;
1728 {
1729
1730 if (inp->inp_socket->so_options & SO_TIMESTAMP) {
1731 struct timeval tv;
1732
1733 microtime(&tv);
1734 *mp = sbcreatecontrol((caddr_t) &tv, sizeof(tv),
1735 SCM_TIMESTAMP, SOL_SOCKET);
1736 if (*mp)
1737 mp = &(*mp)->m_next;
1738 }
1739 if (inp->inp_flags & INP_RECVDSTADDR) {
1740 *mp = sbcreatecontrol((caddr_t) &ip->ip_dst,
1741 sizeof(struct in_addr), IP_RECVDSTADDR, IPPROTO_IP);
1742 if (*mp)
1743 mp = &(*mp)->m_next;
1744 }
1745 #ifdef notyet
1746 /*
1747 * XXX
1748 * Moving these out of udp_input() made them even more broken
1749 * than they already were.
1750 * - fenner (at) parc.xerox.com
1751 */
1752 /* options were tossed already */
1753 if (inp->inp_flags & INP_RECVOPTS) {
1754 *mp = sbcreatecontrol((caddr_t) opts_deleted_above,
1755 sizeof(struct in_addr), IP_RECVOPTS, IPPROTO_IP);
1756 if (*mp)
1757 mp = &(*mp)->m_next;
1758 }
1759 /* ip_srcroute doesn't do what we want here, need to fix */
1760 if (inp->inp_flags & INP_RECVRETOPTS) {
1761 *mp = sbcreatecontrol((caddr_t) ip_srcroute(),
1762 sizeof(struct in_addr), IP_RECVRETOPTS, IPPROTO_IP);
1763 if (*mp)
1764 mp = &(*mp)->m_next;
1765 }
1766 #endif
1767 if (inp->inp_flags & INP_RECVIF) {
1768 struct sockaddr_dl sdl;
1769
1770 sdl.sdl_len = offsetof(struct sockaddr_dl, sdl_data[0]);
1771 sdl.sdl_family = AF_LINK;
1772 sdl.sdl_index = m->m_pkthdr.rcvif ?
1773 m->m_pkthdr.rcvif->if_index : 0;
1774 sdl.sdl_nlen = sdl.sdl_alen = sdl.sdl_slen = 0;
1775 *mp = sbcreatecontrol((caddr_t) &sdl, sdl.sdl_len,
1776 IP_RECVIF, IPPROTO_IP);
1777 if (*mp)
1778 mp = &(*mp)->m_next;
1779 }
1780 }
1781
1782 int
1783 ip_sysctl(name, namelen, oldp, oldlenp, newp, newlen)
1784 int *name;
1785 u_int namelen;
1786 void *oldp;
1787 size_t *oldlenp;
1788 void *newp;
1789 size_t newlen;
1790 {
1791 extern int subnetsarelocal, hostzeroisbroadcast;
1792
1793 int error, old;
1794
1795 /* All sysctl names at this level are terminal. */
1796 if (namelen != 1)
1797 return (ENOTDIR);
1798
1799 switch (name[0]) {
1800 case IPCTL_FORWARDING:
1801 return (sysctl_int(oldp, oldlenp, newp, newlen, &ipforwarding));
1802 case IPCTL_SENDREDIRECTS:
1803 return (sysctl_int(oldp, oldlenp, newp, newlen,
1804 &ipsendredirects));
1805 case IPCTL_DEFTTL:
1806 return (sysctl_int(oldp, oldlenp, newp, newlen, &ip_defttl));
1807 #ifdef notyet
1808 case IPCTL_DEFMTU:
1809 return (sysctl_int(oldp, oldlenp, newp, newlen, &ip_mtu));
1810 #endif
1811 case IPCTL_FORWSRCRT:
1812 /* Don't allow this to change in a secure environment. */
1813 if (securelevel > 0)
1814 return (sysctl_rdint(oldp, oldlenp, newp,
1815 ip_forwsrcrt));
1816 else
1817 return (sysctl_int(oldp, oldlenp, newp, newlen,
1818 &ip_forwsrcrt));
1819 case IPCTL_DIRECTEDBCAST:
1820 return (sysctl_int(oldp, oldlenp, newp, newlen,
1821 &ip_directedbcast));
1822 case IPCTL_ALLOWSRCRT:
1823 return (sysctl_int(oldp, oldlenp, newp, newlen,
1824 &ip_allowsrcrt));
1825 case IPCTL_SUBNETSARELOCAL:
1826 return (sysctl_int(oldp, oldlenp, newp, newlen,
1827 &subnetsarelocal));
1828 case IPCTL_MTUDISC:
1829 error = sysctl_int(oldp, oldlenp, newp, newlen,
1830 &ip_mtudisc);
1831 if (ip_mtudisc != 0 && ip_mtudisc_timeout_q == NULL) {
1832 ip_mtudisc_timeout_q =
1833 rt_timer_queue_create(ip_mtudisc_timeout);
1834 } else if (ip_mtudisc == 0 && ip_mtudisc_timeout_q != NULL) {
1835 rt_timer_queue_destroy(ip_mtudisc_timeout_q, TRUE);
1836 ip_mtudisc_timeout_q = NULL;
1837 }
1838 return error;
1839 case IPCTL_ANONPORTMIN:
1840 old = anonportmin;
1841 error = sysctl_int(oldp, oldlenp, newp, newlen, &anonportmin);
1842 if (anonportmin >= anonportmax || anonportmin < 0
1843 || anonportmin > 65535
1844 #ifndef IPNOPRIVPORTS
1845 || anonportmin < IPPORT_RESERVED
1846 #endif
1847 ) {
1848 anonportmin = old;
1849 return (EINVAL);
1850 }
1851 return (error);
1852 case IPCTL_ANONPORTMAX:
1853 old = anonportmax;
1854 error = sysctl_int(oldp, oldlenp, newp, newlen, &anonportmax);
1855 if (anonportmin >= anonportmax || anonportmax < 0
1856 || anonportmax > 65535
1857 #ifndef IPNOPRIVPORTS
1858 || anonportmax < IPPORT_RESERVED
1859 #endif
1860 ) {
1861 anonportmax = old;
1862 return (EINVAL);
1863 }
1864 return (error);
1865 case IPCTL_MTUDISCTIMEOUT:
1866 error = sysctl_int(oldp, oldlenp, newp, newlen,
1867 &ip_mtudisc_timeout);
1868 if (ip_mtudisc_timeout < 0)
1869 return (EINVAL);
1870 if (ip_mtudisc_timeout_q != NULL)
1871 rt_timer_queue_change(ip_mtudisc_timeout_q,
1872 ip_mtudisc_timeout);
1873 return (error);
1874 #ifdef GATEWAY
1875 case IPCTL_MAXFLOWS:
1876 {
1877 int s;
1878
1879 error = sysctl_int(oldp, oldlenp, newp, newlen,
1880 &ip_maxflows);
1881 s = splsoftnet();
1882 ipflow_reap(0);
1883 splx(s);
1884 return (error);
1885 }
1886 #endif
1887 case IPCTL_HOSTZEROBROADCAST:
1888 return (sysctl_int(oldp, oldlenp, newp, newlen,
1889 &hostzeroisbroadcast));
1890 #if NGIF > 0
1891 case IPCTL_GIF_TTL:
1892 return(sysctl_int(oldp, oldlenp, newp, newlen,
1893 &ip_gif_ttl));
1894 #endif
1895
1896 #if NGRE > 0
1897 case IPCTL_GRE_TTL:
1898 return(sysctl_int(oldp, oldlenp, newp, newlen,
1899 &ip_gre_ttl));
1900 #endif
1901
1902 #ifndef IPNOPRIVPORTS
1903 case IPCTL_LOWPORTMIN:
1904 old = lowportmin;
1905 error = sysctl_int(oldp, oldlenp, newp, newlen, &lowportmin);
1906 if (lowportmin >= lowportmax
1907 || lowportmin > IPPORT_RESERVEDMAX
1908 || lowportmin < IPPORT_RESERVEDMIN
1909 ) {
1910 lowportmin = old;
1911 return (EINVAL);
1912 }
1913 return (error);
1914 case IPCTL_LOWPORTMAX:
1915 old = lowportmax;
1916 error = sysctl_int(oldp, oldlenp, newp, newlen, &lowportmax);
1917 if (lowportmin >= lowportmax
1918 || lowportmax > IPPORT_RESERVEDMAX
1919 || lowportmax < IPPORT_RESERVEDMIN
1920 ) {
1921 lowportmax = old;
1922 return (EINVAL);
1923 }
1924 return (error);
1925 #endif
1926
1927 case IPCTL_MAXFRAGPACKETS:
1928 return (sysctl_int(oldp, oldlenp, newp, newlen,
1929 &ip_maxfragpackets));
1930
1931 default:
1932 return (EOPNOTSUPP);
1933 }
1934 /* NOTREACHED */
1935 }
1936