ip_input.c revision 1.359 1 /* $NetBSD: ip_input.c,v 1.359 2017/07/19 07:24:46 ozaki-r Exp $ */
2
3 /*
4 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the project nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31
32 /*-
33 * Copyright (c) 1998 The NetBSD Foundation, Inc.
34 * All rights reserved.
35 *
36 * This code is derived from software contributed to The NetBSD Foundation
37 * by Public Access Networks Corporation ("Panix"). It was developed under
38 * contract to Panix by Eric Haszlakiewicz and Thor Lancelot Simon.
39 *
40 * Redistribution and use in source and binary forms, with or without
41 * modification, are permitted provided that the following conditions
42 * are met:
43 * 1. Redistributions of source code must retain the above copyright
44 * notice, this list of conditions and the following disclaimer.
45 * 2. Redistributions in binary form must reproduce the above copyright
46 * notice, this list of conditions and the following disclaimer in the
47 * documentation and/or other materials provided with the distribution.
48 *
49 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
50 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
51 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
52 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
53 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
54 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
55 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
56 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
57 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
58 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
59 * POSSIBILITY OF SUCH DAMAGE.
60 */
61
62 /*
63 * Copyright (c) 1982, 1986, 1988, 1993
64 * The Regents of the University of California. All rights reserved.
65 *
66 * Redistribution and use in source and binary forms, with or without
67 * modification, are permitted provided that the following conditions
68 * are met:
69 * 1. Redistributions of source code must retain the above copyright
70 * notice, this list of conditions and the following disclaimer.
71 * 2. Redistributions in binary form must reproduce the above copyright
72 * notice, this list of conditions and the following disclaimer in the
73 * documentation and/or other materials provided with the distribution.
74 * 3. Neither the name of the University nor the names of its contributors
75 * may be used to endorse or promote products derived from this software
76 * without specific prior written permission.
77 *
78 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
79 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
80 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
81 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
82 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
83 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
84 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
85 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
86 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
87 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
88 * SUCH DAMAGE.
89 *
90 * @(#)ip_input.c 8.2 (Berkeley) 1/4/94
91 */
92
93 #include <sys/cdefs.h>
94 __KERNEL_RCSID(0, "$NetBSD: ip_input.c,v 1.359 2017/07/19 07:24:46 ozaki-r Exp $");
95
96 #ifdef _KERNEL_OPT
97 #include "opt_inet.h"
98 #include "opt_gateway.h"
99 #include "opt_ipsec.h"
100 #include "opt_mrouting.h"
101 #include "opt_mbuftrace.h"
102 #include "opt_inet_csum.h"
103 #include "opt_net_mpsafe.h"
104 #endif
105
106 #include "arp.h"
107
108 #include <sys/param.h>
109 #include <sys/systm.h>
110 #include <sys/cpu.h>
111 #include <sys/mbuf.h>
112 #include <sys/domain.h>
113 #include <sys/protosw.h>
114 #include <sys/socket.h>
115 #include <sys/socketvar.h>
116 #include <sys/errno.h>
117 #include <sys/time.h>
118 #include <sys/kernel.h>
119 #include <sys/pool.h>
120 #include <sys/sysctl.h>
121 #include <sys/kauth.h>
122
123 #include <net/if.h>
124 #include <net/if_dl.h>
125 #include <net/route.h>
126 #include <net/pktqueue.h>
127 #include <net/pfil.h>
128
129 #include <netinet/in.h>
130 #include <netinet/in_systm.h>
131 #include <netinet/ip.h>
132 #include <netinet/in_pcb.h>
133 #include <netinet/in_proto.h>
134 #include <netinet/in_var.h>
135 #include <netinet/ip_var.h>
136 #include <netinet/ip_private.h>
137 #include <netinet/ip_icmp.h>
138 /* just for gif_ttl */
139 #include <netinet/in_gif.h>
140 #include "gif.h"
141 #include <net/if_gre.h>
142 #include "gre.h"
143
144 #ifdef MROUTING
145 #include <netinet/ip_mroute.h>
146 #endif
147 #include <netinet/portalgo.h>
148
149 #ifdef IPSEC
150 #include <netipsec/ipsec.h>
151 #endif
152
153 #ifndef IPFORWARDING
154 #ifdef GATEWAY
155 #define IPFORWARDING 1 /* forward IP packets not for us */
156 #else /* GATEWAY */
157 #define IPFORWARDING 0 /* don't forward IP packets not for us */
158 #endif /* GATEWAY */
159 #endif /* IPFORWARDING */
160 #ifndef IPSENDREDIRECTS
161 #define IPSENDREDIRECTS 1
162 #endif
163 #ifndef IPFORWSRCRT
164 #define IPFORWSRCRT 1 /* forward source-routed packets */
165 #endif
166 #ifndef IPALLOWSRCRT
167 #define IPALLOWSRCRT 1 /* allow source-routed packets */
168 #endif
169 #ifndef IPMTUDISC
170 #define IPMTUDISC 1
171 #endif
172 #ifndef IPMTUDISCTIMEOUT
173 #define IPMTUDISCTIMEOUT (10 * 60) /* as per RFC 1191 */
174 #endif
175
176 /*
177 * Note: DIRECTED_BROADCAST is handled this way so that previous
178 * configuration using this option will Just Work.
179 */
180 #ifndef IPDIRECTEDBCAST
181 #ifdef DIRECTED_BROADCAST
182 #define IPDIRECTEDBCAST 1
183 #else
184 #define IPDIRECTEDBCAST 0
185 #endif /* DIRECTED_BROADCAST */
186 #endif /* IPDIRECTEDBCAST */
187 int ipforwarding = IPFORWARDING;
188 int ipsendredirects = IPSENDREDIRECTS;
189 int ip_defttl = IPDEFTTL;
190 int ip_forwsrcrt = IPFORWSRCRT;
191 int ip_directedbcast = IPDIRECTEDBCAST;
192 int ip_allowsrcrt = IPALLOWSRCRT;
193 int ip_mtudisc = IPMTUDISC;
194 int ip_mtudisc_timeout = IPMTUDISCTIMEOUT;
195 #ifdef DIAGNOSTIC
196 int ipprintfs = 0;
197 #endif
198
199 int ip_do_randomid = 0;
200
201 /*
202 * XXX - Setting ip_checkinterface mostly implements the receive side of
203 * the Strong ES model described in RFC 1122, but since the routing table
204 * and transmit implementation do not implement the Strong ES model,
205 * setting this to 1 results in an odd hybrid.
206 *
207 * XXX - ip_checkinterface currently must be disabled if you use ipnat
208 * to translate the destination address to another local interface.
209 *
210 * XXX - ip_checkinterface must be disabled if you add IP aliases
211 * to the loopback interface instead of the interface where the
212 * packets for those addresses are received.
213 */
214 static int ip_checkinterface __read_mostly = 0;
215
216 struct rttimer_queue *ip_mtudisc_timeout_q = NULL;
217
218 pktqueue_t * ip_pktq __read_mostly;
219 pfil_head_t * inet_pfil_hook __read_mostly;
220 ipid_state_t * ip_ids __read_mostly;
221 percpu_t * ipstat_percpu __read_mostly;
222
223 static percpu_t *ipforward_rt_percpu __cacheline_aligned;
224
225 uint16_t ip_id;
226
227 #ifdef INET_CSUM_COUNTERS
228 #include <sys/device.h>
229
230 struct evcnt ip_hwcsum_bad = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
231 NULL, "inet", "hwcsum bad");
232 struct evcnt ip_hwcsum_ok = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
233 NULL, "inet", "hwcsum ok");
234 struct evcnt ip_swcsum = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
235 NULL, "inet", "swcsum");
236
237 #define INET_CSUM_COUNTER_INCR(ev) (ev)->ev_count++
238
239 EVCNT_ATTACH_STATIC(ip_hwcsum_bad);
240 EVCNT_ATTACH_STATIC(ip_hwcsum_ok);
241 EVCNT_ATTACH_STATIC(ip_swcsum);
242
243 #else
244
245 #define INET_CSUM_COUNTER_INCR(ev) /* nothing */
246
247 #endif /* INET_CSUM_COUNTERS */
248
249 /*
250 * Used to save the IP options in case a protocol wants to respond
251 * to an incoming packet over the same route if the packet got here
252 * using IP source routing. This allows connection establishment and
253 * maintenance when the remote end is on a network that is not known
254 * to us.
255 */
256 struct ip_srcrt {
257 int isr_nhops; /* number of hops */
258 struct in_addr isr_dst; /* final destination */
259 char isr_nop; /* one NOP to align */
260 char isr_hdr[IPOPT_OFFSET + 1]; /* OPTVAL, OLEN & OFFSET */
261 struct in_addr isr_routes[MAX_IPOPTLEN/sizeof(struct in_addr)];
262 };
263
264 static int ip_drainwanted;
265
266 static void save_rte(struct mbuf *, u_char *, struct in_addr);
267
268 #ifdef MBUFTRACE
269 struct mowner ip_rx_mowner = MOWNER_INIT("internet", "rx");
270 struct mowner ip_tx_mowner = MOWNER_INIT("internet", "tx");
271 #endif
272
273 static void ipintr(void *);
274 static void ip_input(struct mbuf *);
275 static void ip_forward(struct mbuf *, int, struct ifnet *);
276 static bool ip_dooptions(struct mbuf *);
277 static struct in_ifaddr *ip_rtaddr(struct in_addr, struct psref *);
278 static void sysctl_net_inet_ip_setup(struct sysctllog **);
279
280 static struct in_ifaddr *ip_match_our_address(struct ifnet *, struct ip *,
281 int *);
282 static struct in_ifaddr *ip_match_our_address_broadcast(struct ifnet *,
283 struct ip *);
284
285 #ifdef NET_MPSAFE
286 #define SOFTNET_LOCK() mutex_enter(softnet_lock)
287 #define SOFTNET_UNLOCK() mutex_exit(softnet_lock)
288 #else
289 #define SOFTNET_LOCK() KASSERT(mutex_owned(softnet_lock))
290 #define SOFTNET_UNLOCK() KASSERT(mutex_owned(softnet_lock))
291 #endif
292
293 /*
294 * IP initialization: fill in IP protocol switch table.
295 * All protocols not implemented in kernel go to raw IP protocol handler.
296 */
297 void
298 ip_init(void)
299 {
300 const struct protosw *pr;
301
302 in_init();
303 sysctl_net_inet_ip_setup(NULL);
304
305 pr = pffindproto(PF_INET, IPPROTO_RAW, SOCK_RAW);
306 KASSERT(pr != NULL);
307
308 ip_pktq = pktq_create(IFQ_MAXLEN, ipintr, NULL);
309 KASSERT(ip_pktq != NULL);
310
311 for (u_int i = 0; i < IPPROTO_MAX; i++) {
312 ip_protox[i] = pr - inetsw;
313 }
314 for (pr = inetdomain.dom_protosw;
315 pr < inetdomain.dom_protoswNPROTOSW; pr++)
316 if (pr->pr_domain->dom_family == PF_INET &&
317 pr->pr_protocol && pr->pr_protocol != IPPROTO_RAW)
318 ip_protox[pr->pr_protocol] = pr - inetsw;
319
320 ip_reass_init();
321
322 ip_ids = ip_id_init();
323 ip_id = time_uptime & 0xfffff;
324
325 #ifdef GATEWAY
326 ipflow_init();
327 #endif
328
329 /* Register our Packet Filter hook. */
330 inet_pfil_hook = pfil_head_create(PFIL_TYPE_AF, (void *)AF_INET);
331 KASSERT(inet_pfil_hook != NULL);
332
333 #ifdef MBUFTRACE
334 MOWNER_ATTACH(&ip_tx_mowner);
335 MOWNER_ATTACH(&ip_rx_mowner);
336 #endif /* MBUFTRACE */
337
338 ipstat_percpu = percpu_alloc(sizeof(uint64_t) * IP_NSTATS);
339 ipforward_rt_percpu = percpu_alloc(sizeof(struct route));
340 ip_mtudisc_timeout_q = rt_timer_queue_create(ip_mtudisc_timeout);
341 }
342
343 static struct in_ifaddr *
344 ip_match_our_address(struct ifnet *ifp, struct ip *ip, int *downmatch)
345 {
346 struct in_ifaddr *ia = NULL;
347 int checkif;
348
349 /*
350 * Enable a consistency check between the destination address
351 * and the arrival interface for a unicast packet (the RFC 1122
352 * strong ES model) if IP forwarding is disabled and the packet
353 * is not locally generated.
354 *
355 * XXX - Checking also should be disabled if the destination
356 * address is ipnat'ed to a different interface.
357 *
358 * XXX - Checking is incompatible with IP aliases added
359 * to the loopback interface instead of the interface where
360 * the packets are received.
361 *
362 * XXX - We need to add a per ifaddr flag for this so that
363 * we get finer grain control.
364 */
365 checkif = ip_checkinterface && (ipforwarding == 0) &&
366 (ifp->if_flags & IFF_LOOPBACK) == 0;
367
368 IN_ADDRHASH_READER_FOREACH(ia, ip->ip_dst.s_addr) {
369 if (in_hosteq(ia->ia_addr.sin_addr, ip->ip_dst)) {
370 if (ia->ia4_flags & IN_IFF_NOTREADY)
371 continue;
372 if (checkif && ia->ia_ifp != ifp)
373 continue;
374 if ((ia->ia_ifp->if_flags & IFF_UP) != 0 &&
375 (ia->ia4_flags & IN_IFF_DETACHED) == 0)
376 break;
377 else
378 (*downmatch)++;
379 }
380 }
381
382 return ia;
383 }
384
385 static struct in_ifaddr *
386 ip_match_our_address_broadcast(struct ifnet *ifp, struct ip *ip)
387 {
388 struct in_ifaddr *ia = NULL;
389 struct ifaddr *ifa;
390
391 IFADDR_READER_FOREACH(ifa, ifp) {
392 if (ifa->ifa_addr->sa_family != AF_INET)
393 continue;
394 ia = ifatoia(ifa);
395 if (ia->ia4_flags & (IN_IFF_NOTREADY | IN_IFF_DETACHED))
396 continue;
397 if (in_hosteq(ip->ip_dst, ia->ia_broadaddr.sin_addr) ||
398 in_hosteq(ip->ip_dst, ia->ia_netbroadcast) ||
399 /*
400 * Look for all-0's host part (old broadcast addr),
401 * either for subnet or net.
402 */
403 ip->ip_dst.s_addr == ia->ia_subnet ||
404 ip->ip_dst.s_addr == ia->ia_net)
405 goto matched;
406 /*
407 * An interface with IP address zero accepts
408 * all packets that arrive on that interface.
409 */
410 if (in_nullhost(ia->ia_addr.sin_addr))
411 goto matched;
412 }
413 ia = NULL;
414
415 matched:
416 return ia;
417 }
418
419 /*
420 * IP software interrupt routine.
421 */
422 static void
423 ipintr(void *arg __unused)
424 {
425 struct mbuf *m;
426
427 KASSERT(cpu_softintr_p());
428
429 #ifndef NET_MPSAFE
430 mutex_enter(softnet_lock);
431 #endif
432 while ((m = pktq_dequeue(ip_pktq)) != NULL) {
433 ip_input(m);
434 }
435 #ifndef NET_MPSAFE
436 mutex_exit(softnet_lock);
437 #endif
438 }
439
440 /*
441 * IP input routine. Checksum and byte swap header. If fragmented
442 * try to reassemble. Process options. Pass to next level.
443 */
444 static void
445 ip_input(struct mbuf *m)
446 {
447 struct ip *ip = NULL;
448 struct in_ifaddr *ia = NULL;
449 int hlen = 0, len;
450 int downmatch;
451 int srcrt = 0;
452 ifnet_t *ifp;
453 struct psref psref;
454 int s;
455
456 KASSERTMSG(cpu_softintr_p(), "ip_input: not in the software "
457 "interrupt handler; synchronization assumptions violated");
458
459 MCLAIM(m, &ip_rx_mowner);
460 KASSERT((m->m_flags & M_PKTHDR) != 0);
461
462 ifp = m_get_rcvif_psref(m, &psref);
463 if (__predict_false(ifp == NULL))
464 goto out;
465
466 /*
467 * If no IP addresses have been set yet but the interfaces
468 * are receiving, can't do anything with incoming packets yet.
469 * Note: we pre-check without locks held.
470 */
471 if (IN_ADDRLIST_READER_EMPTY())
472 goto out;
473 IP_STATINC(IP_STAT_TOTAL);
474
475 /*
476 * If the IP header is not aligned, slurp it up into a new
477 * mbuf with space for link headers, in the event we forward
478 * it. Otherwise, if it is aligned, make sure the entire
479 * base IP header is in the first mbuf of the chain.
480 */
481 if (IP_HDR_ALIGNED_P(mtod(m, void *)) == 0) {
482 if ((m = m_copyup(m, sizeof(struct ip),
483 (max_linkhdr + 3) & ~3)) == NULL) {
484 /* XXXJRT new stat, please */
485 IP_STATINC(IP_STAT_TOOSMALL);
486 goto out;
487 }
488 } else if (__predict_false(m->m_len < sizeof (struct ip))) {
489 if ((m = m_pullup(m, sizeof (struct ip))) == NULL) {
490 IP_STATINC(IP_STAT_TOOSMALL);
491 goto out;
492 }
493 }
494 ip = mtod(m, struct ip *);
495 if (ip->ip_v != IPVERSION) {
496 IP_STATINC(IP_STAT_BADVERS);
497 goto out;
498 }
499 hlen = ip->ip_hl << 2;
500 if (hlen < sizeof(struct ip)) { /* minimum header length */
501 IP_STATINC(IP_STAT_BADHLEN);
502 goto out;
503 }
504 if (hlen > m->m_len) {
505 if ((m = m_pullup(m, hlen)) == NULL) {
506 IP_STATINC(IP_STAT_BADHLEN);
507 goto out;
508 }
509 ip = mtod(m, struct ip *);
510 }
511
512 /*
513 * RFC1122: packets with a multicast source address are
514 * not allowed.
515 */
516 if (IN_MULTICAST(ip->ip_src.s_addr)) {
517 IP_STATINC(IP_STAT_BADADDR);
518 goto out;
519 }
520
521 /* 127/8 must not appear on wire - RFC1122 */
522 if ((ntohl(ip->ip_dst.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET ||
523 (ntohl(ip->ip_src.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET) {
524 if ((ifp->if_flags & IFF_LOOPBACK) == 0) {
525 IP_STATINC(IP_STAT_BADADDR);
526 goto out;
527 }
528 }
529
530 switch (m->m_pkthdr.csum_flags &
531 ((ifp->if_csum_flags_rx & M_CSUM_IPv4) |
532 M_CSUM_IPv4_BAD)) {
533 case M_CSUM_IPv4|M_CSUM_IPv4_BAD:
534 INET_CSUM_COUNTER_INCR(&ip_hwcsum_bad);
535 IP_STATINC(IP_STAT_BADSUM);
536 goto out;
537
538 case M_CSUM_IPv4:
539 /* Checksum was okay. */
540 INET_CSUM_COUNTER_INCR(&ip_hwcsum_ok);
541 break;
542
543 default:
544 /*
545 * Must compute it ourselves. Maybe skip checksum on
546 * loopback interfaces.
547 */
548 if (__predict_true(!(ifp->if_flags & IFF_LOOPBACK) ||
549 ip_do_loopback_cksum)) {
550 INET_CSUM_COUNTER_INCR(&ip_swcsum);
551 if (in_cksum(m, hlen) != 0) {
552 IP_STATINC(IP_STAT_BADSUM);
553 goto out;
554 }
555 }
556 break;
557 }
558
559 /* Retrieve the packet length. */
560 len = ntohs(ip->ip_len);
561
562 /*
563 * Check for additional length bogosity
564 */
565 if (len < hlen) {
566 IP_STATINC(IP_STAT_BADLEN);
567 goto out;
568 }
569
570 /*
571 * Check that the amount of data in the buffers
572 * is as at least much as the IP header would have us expect.
573 * Trim mbufs if longer than we expect.
574 * Drop packet if shorter than we expect.
575 */
576 if (m->m_pkthdr.len < len) {
577 IP_STATINC(IP_STAT_TOOSHORT);
578 goto out;
579 }
580 if (m->m_pkthdr.len > len) {
581 if (m->m_len == m->m_pkthdr.len) {
582 m->m_len = len;
583 m->m_pkthdr.len = len;
584 } else
585 m_adj(m, len - m->m_pkthdr.len);
586 }
587
588 /*
589 * Assume that we can create a fast-forward IP flow entry
590 * based on this packet.
591 */
592 m->m_flags |= M_CANFASTFWD;
593
594 /*
595 * Run through list of hooks for input packets. If there are any
596 * filters which require that additional packets in the flow are
597 * not fast-forwarded, they must clear the M_CANFASTFWD flag.
598 * Note that filters must _never_ set this flag, as another filter
599 * in the list may have previously cleared it.
600 */
601 #if defined(IPSEC)
602 if (!ipsec_used || !ipsec_indone(m))
603 #else
604 if (1)
605 #endif
606 {
607 struct in_addr odst = ip->ip_dst;
608 bool freed;
609
610 freed = pfil_run_hooks(inet_pfil_hook, &m, ifp, PFIL_IN) != 0;
611 if (freed || m == NULL) {
612 m = NULL;
613 goto out;
614 }
615 ip = mtod(m, struct ip *);
616 hlen = ip->ip_hl << 2;
617
618 /*
619 * XXX The setting of "srcrt" here is to prevent ip_forward()
620 * from generating ICMP redirects for packets that have
621 * been redirected by a hook back out on to the same LAN that
622 * they came from and is not an indication that the packet
623 * is being inffluenced by source routing options. This
624 * allows things like
625 * "rdr tlp0 0/0 port 80 -> 1.1.1.200 3128 tcp"
626 * where tlp0 is both on the 1.1.1.0/24 network and is the
627 * default route for hosts on 1.1.1.0/24. Of course this
628 * also requires a "map tlp0 ..." to complete the story.
629 * One might argue whether or not this kind of network config.
630 * should be supported in this manner...
631 */
632 srcrt = (odst.s_addr != ip->ip_dst.s_addr);
633 }
634
635 #ifdef ALTQ
636 /* XXX Temporary until ALTQ is changed to use a pfil hook */
637 if (altq_input) {
638 SOFTNET_LOCK();
639 if ((*altq_input)(m, AF_INET) == 0) {
640 /* Packet dropped by traffic conditioner. */
641 SOFTNET_UNLOCK();
642 m = NULL;
643 goto out;
644 }
645 SOFTNET_UNLOCK();
646 }
647 #endif
648
649 /*
650 * Process options and, if not destined for us,
651 * ship it on. ip_dooptions returns 1 when an
652 * error was detected (causing an icmp message
653 * to be sent and the original packet to be freed).
654 */
655 if (hlen > sizeof (struct ip) && ip_dooptions(m)) {
656 m = NULL;
657 goto out;
658 }
659
660 /*
661 * Check our list of addresses, to see if the packet is for us.
662 *
663 * Traditional 4.4BSD did not consult IFF_UP at all.
664 * The behavior here is to treat addresses on !IFF_UP interface
665 * or IN_IFF_NOTREADY addresses as not mine.
666 */
667 downmatch = 0;
668 s = pserialize_read_enter();
669 ia = ip_match_our_address(ifp, ip, &downmatch);
670 if (ia != NULL) {
671 pserialize_read_exit(s);
672 goto ours;
673 }
674
675 if (ifp->if_flags & IFF_BROADCAST) {
676 ia = ip_match_our_address_broadcast(ifp, ip);
677 if (ia != NULL) {
678 pserialize_read_exit(s);
679 goto ours;
680 }
681 }
682 pserialize_read_exit(s);
683
684 if (IN_MULTICAST(ip->ip_dst.s_addr)) {
685 #ifdef MROUTING
686 extern struct socket *ip_mrouter;
687
688 if (ip_mrouter) {
689 /*
690 * If we are acting as a multicast router, all
691 * incoming multicast packets are passed to the
692 * kernel-level multicast forwarding function.
693 * The packet is returned (relatively) intact; if
694 * ip_mforward() returns a non-zero value, the packet
695 * must be discarded, else it may be accepted below.
696 *
697 * (The IP ident field is put in the same byte order
698 * as expected when ip_mforward() is called from
699 * ip_output().)
700 */
701 SOFTNET_LOCK();
702 if (ip_mforward(m, ifp) != 0) {
703 SOFTNET_UNLOCK();
704 IP_STATINC(IP_STAT_CANTFORWARD);
705 goto out;
706 }
707 SOFTNET_UNLOCK();
708
709 /*
710 * The process-level routing demon needs to receive
711 * all multicast IGMP packets, whether or not this
712 * host belongs to their destination groups.
713 */
714 if (ip->ip_p == IPPROTO_IGMP) {
715 goto ours;
716 }
717 IP_STATINC(IP_STAT_CANTFORWARD);
718 }
719 #endif
720 /*
721 * See if we belong to the destination multicast group on the
722 * arrival interface.
723 */
724 if (!in_multi_group(ip->ip_dst, ifp, 0)) {
725 IP_STATINC(IP_STAT_CANTFORWARD);
726 goto out;
727 }
728 goto ours;
729 }
730 if (ip->ip_dst.s_addr == INADDR_BROADCAST ||
731 in_nullhost(ip->ip_dst))
732 goto ours;
733
734 /*
735 * Not for us; forward if possible and desirable.
736 */
737 if (ipforwarding == 0) {
738 m_put_rcvif_psref(ifp, &psref);
739 IP_STATINC(IP_STAT_CANTFORWARD);
740 m_freem(m);
741 } else {
742 /*
743 * If ip_dst matched any of my address on !IFF_UP interface,
744 * and there's no IFF_UP interface that matches ip_dst,
745 * send icmp unreach. Forwarding it will result in in-kernel
746 * forwarding loop till TTL goes to 0.
747 */
748 if (downmatch) {
749 m_put_rcvif_psref(ifp, &psref);
750 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_HOST, 0, 0);
751 IP_STATINC(IP_STAT_CANTFORWARD);
752 return;
753 }
754 #ifdef IPSEC
755 /* Check the security policy (SP) for the packet */
756 if (ipsec_used) {
757 SOFTNET_LOCK();
758 if (ipsec4_input(m, IP_FORWARDING |
759 (ip_directedbcast ? IP_ALLOWBROADCAST : 0)) != 0) {
760 SOFTNET_UNLOCK();
761 goto out;
762 }
763 SOFTNET_UNLOCK();
764 }
765 #endif
766 ip_forward(m, srcrt, ifp);
767 m_put_rcvif_psref(ifp, &psref);
768 }
769 return;
770
771 ours:
772 m_put_rcvif_psref(ifp, &psref);
773 ifp = NULL;
774
775 /*
776 * If offset or IP_MF are set, must reassemble.
777 */
778 if (ip->ip_off & ~htons(IP_DF|IP_RF)) {
779 /*
780 * Pass to IP reassembly mechanism.
781 */
782 if (ip_reass_packet(&m, ip) != 0) {
783 /* Failed; invalid fragment(s) or packet. */
784 goto out;
785 }
786 if (m == NULL) {
787 /* More fragments should come; silently return. */
788 goto out;
789 }
790 /*
791 * Reassembly is done, we have the final packet.
792 * Updated cached data in local variable(s).
793 */
794 ip = mtod(m, struct ip *);
795 hlen = ip->ip_hl << 2;
796 }
797
798 #ifdef IPSEC
799 /*
800 * Enforce IPsec policy checking if we are seeing last header.
801 * Note that we do not visit this with protocols with PCB layer
802 * code - like UDP/TCP/raw IP.
803 */
804 if (ipsec_used &&
805 (inetsw[ip_protox[ip->ip_p]].pr_flags & PR_LASTHDR) != 0) {
806 SOFTNET_LOCK();
807 if (ipsec4_input(m, 0) != 0) {
808 SOFTNET_UNLOCK();
809 goto out;
810 }
811 SOFTNET_UNLOCK();
812 }
813 #endif
814
815 /*
816 * Switch out to protocol's input routine.
817 */
818 #if IFA_STATS
819 if (ia && ip) {
820 struct in_ifaddr *_ia;
821 /*
822 * Keep a reference from ip_match_our_address with psref
823 * is expensive, so explore ia here again.
824 */
825 s = pserialize_read_enter();
826 _ia = in_get_ia(ip->ip_dst);
827 _ia->ia_ifa.ifa_data.ifad_inbytes += ntohs(ip->ip_len);
828 pserialize_read_exit(s);
829 }
830 #endif
831 IP_STATINC(IP_STAT_DELIVERED);
832
833 const int off = hlen, nh = ip->ip_p;
834
835 SOFTNET_LOCK();
836 (*inetsw[ip_protox[nh]].pr_input)(m, off, nh);
837 SOFTNET_UNLOCK();
838 return;
839
840 out:
841 m_put_rcvif_psref(ifp, &psref);
842 if (m != NULL)
843 m_freem(m);
844 }
845
846 /*
847 * IP timer processing.
848 */
849 void
850 ip_slowtimo(void)
851 {
852
853 #ifndef NET_MPSAFE
854 mutex_enter(softnet_lock);
855 KERNEL_LOCK(1, NULL);
856 #endif
857
858 ip_reass_slowtimo();
859
860 #ifndef NET_MPSAFE
861 KERNEL_UNLOCK_ONE(NULL);
862 mutex_exit(softnet_lock);
863 #endif
864 }
865
866 /*
867 * IP drain processing.
868 */
869 void
870 ip_drain(void)
871 {
872
873 KERNEL_LOCK(1, NULL);
874 ip_reass_drain();
875 KERNEL_UNLOCK_ONE(NULL);
876 }
877
878 /*
879 * ip_dooptions: perform option processing on a datagram, possibly discarding
880 * it if bad options are encountered, or forwarding it if source-routed.
881 *
882 * => Returns true if packet has been forwarded/freed.
883 * => Returns false if the packet should be processed further.
884 */
885 static bool
886 ip_dooptions(struct mbuf *m)
887 {
888 struct ip *ip = mtod(m, struct ip *);
889 u_char *cp, *cp0;
890 struct ip_timestamp *ipt;
891 struct in_ifaddr *ia;
892 int opt, optlen, cnt, off, code, type = ICMP_PARAMPROB, forward = 0;
893 struct in_addr dst;
894 n_time ntime;
895 struct ifaddr *ifa = NULL;
896 int s;
897
898 dst = ip->ip_dst;
899 cp = (u_char *)(ip + 1);
900 cnt = (ip->ip_hl << 2) - sizeof (struct ip);
901 for (; cnt > 0; cnt -= optlen, cp += optlen) {
902 opt = cp[IPOPT_OPTVAL];
903 if (opt == IPOPT_EOL)
904 break;
905 if (opt == IPOPT_NOP)
906 optlen = 1;
907 else {
908 if (cnt < IPOPT_OLEN + sizeof(*cp)) {
909 code = &cp[IPOPT_OLEN] - (u_char *)ip;
910 goto bad;
911 }
912 optlen = cp[IPOPT_OLEN];
913 if (optlen < IPOPT_OLEN + sizeof(*cp) || optlen > cnt) {
914 code = &cp[IPOPT_OLEN] - (u_char *)ip;
915 goto bad;
916 }
917 }
918 switch (opt) {
919
920 default:
921 break;
922
923 /*
924 * Source routing with record.
925 * Find interface with current destination address.
926 * If none on this machine then drop if strictly routed,
927 * or do nothing if loosely routed.
928 * Record interface address and bring up next address
929 * component. If strictly routed make sure next
930 * address is on directly accessible net.
931 */
932 case IPOPT_LSRR:
933 case IPOPT_SSRR: {
934 struct psref psref;
935 struct sockaddr_in ipaddr = {
936 .sin_len = sizeof(ipaddr),
937 .sin_family = AF_INET,
938 };
939
940 if (ip_allowsrcrt == 0) {
941 type = ICMP_UNREACH;
942 code = ICMP_UNREACH_NET_PROHIB;
943 goto bad;
944 }
945 if (optlen < IPOPT_OFFSET + sizeof(*cp)) {
946 code = &cp[IPOPT_OLEN] - (u_char *)ip;
947 goto bad;
948 }
949 if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) {
950 code = &cp[IPOPT_OFFSET] - (u_char *)ip;
951 goto bad;
952 }
953 ipaddr.sin_addr = ip->ip_dst;
954
955 s = pserialize_read_enter();
956 ifa = ifa_ifwithaddr(sintosa(&ipaddr));
957 if (ifa == NULL) {
958 pserialize_read_exit(s);
959 if (opt == IPOPT_SSRR) {
960 type = ICMP_UNREACH;
961 code = ICMP_UNREACH_SRCFAIL;
962 goto bad;
963 }
964 /*
965 * Loose routing, and not at next destination
966 * yet; nothing to do except forward.
967 */
968 break;
969 }
970 pserialize_read_exit(s);
971
972 off--; /* 0 origin */
973 if ((off + sizeof(struct in_addr)) > optlen) {
974 /*
975 * End of source route. Should be for us.
976 */
977 save_rte(m, cp, ip->ip_src);
978 break;
979 }
980 /*
981 * locate outgoing interface
982 */
983 memcpy((void *)&ipaddr.sin_addr, (void *)(cp + off),
984 sizeof(ipaddr.sin_addr));
985 if (opt == IPOPT_SSRR) {
986 ifa = ifa_ifwithladdr_psref(sintosa(&ipaddr),
987 &psref);
988 if (ifa != NULL)
989 ia = ifatoia(ifa);
990 else
991 ia = NULL;
992 } else {
993 ia = ip_rtaddr(ipaddr.sin_addr, &psref);
994 }
995 if (ia == NULL) {
996 type = ICMP_UNREACH;
997 code = ICMP_UNREACH_SRCFAIL;
998 goto bad;
999 }
1000 ip->ip_dst = ipaddr.sin_addr;
1001 bcopy((void *)&ia->ia_addr.sin_addr,
1002 (void *)(cp + off), sizeof(struct in_addr));
1003 ia4_release(ia, &psref);
1004 cp[IPOPT_OFFSET] += sizeof(struct in_addr);
1005 /*
1006 * Let ip_intr's mcast routing check handle mcast pkts
1007 */
1008 forward = !IN_MULTICAST(ip->ip_dst.s_addr);
1009 break;
1010 }
1011
1012 case IPOPT_RR: {
1013 struct psref psref;
1014 struct sockaddr_in ipaddr = {
1015 .sin_len = sizeof(ipaddr),
1016 .sin_family = AF_INET,
1017 };
1018
1019 if (optlen < IPOPT_OFFSET + sizeof(*cp)) {
1020 code = &cp[IPOPT_OLEN] - (u_char *)ip;
1021 goto bad;
1022 }
1023 if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) {
1024 code = &cp[IPOPT_OFFSET] - (u_char *)ip;
1025 goto bad;
1026 }
1027 /*
1028 * If no space remains, ignore.
1029 */
1030 off--; /* 0 origin */
1031 if ((off + sizeof(struct in_addr)) > optlen)
1032 break;
1033 memcpy((void *)&ipaddr.sin_addr, (void *)(&ip->ip_dst),
1034 sizeof(ipaddr.sin_addr));
1035 /*
1036 * locate outgoing interface; if we're the destination,
1037 * use the incoming interface (should be same).
1038 */
1039 ifa = ifa_ifwithaddr_psref(sintosa(&ipaddr), &psref);
1040 if (ifa == NULL) {
1041 ia = ip_rtaddr(ipaddr.sin_addr, &psref);
1042 if (ia == NULL) {
1043 type = ICMP_UNREACH;
1044 code = ICMP_UNREACH_HOST;
1045 goto bad;
1046 }
1047 } else {
1048 ia = ifatoia(ifa);
1049 }
1050 bcopy((void *)&ia->ia_addr.sin_addr,
1051 (void *)(cp + off), sizeof(struct in_addr));
1052 ia4_release(ia, &psref);
1053 cp[IPOPT_OFFSET] += sizeof(struct in_addr);
1054 break;
1055 }
1056
1057 case IPOPT_TS:
1058 code = cp - (u_char *)ip;
1059 ipt = (struct ip_timestamp *)cp;
1060 if (ipt->ipt_len < 4 || ipt->ipt_len > 40) {
1061 code = (u_char *)&ipt->ipt_len - (u_char *)ip;
1062 goto bad;
1063 }
1064 if (ipt->ipt_ptr < 5) {
1065 code = (u_char *)&ipt->ipt_ptr - (u_char *)ip;
1066 goto bad;
1067 }
1068 if (ipt->ipt_ptr > ipt->ipt_len - sizeof (int32_t)) {
1069 if (++ipt->ipt_oflw == 0) {
1070 code = (u_char *)&ipt->ipt_ptr -
1071 (u_char *)ip;
1072 goto bad;
1073 }
1074 break;
1075 }
1076 cp0 = (cp + ipt->ipt_ptr - 1);
1077 switch (ipt->ipt_flg) {
1078
1079 case IPOPT_TS_TSONLY:
1080 break;
1081
1082 case IPOPT_TS_TSANDADDR: {
1083 struct ifnet *rcvif;
1084 int _s, _ss;
1085 struct sockaddr_in ipaddr = {
1086 .sin_len = sizeof(ipaddr),
1087 .sin_family = AF_INET,
1088 };
1089
1090 if (ipt->ipt_ptr - 1 + sizeof(n_time) +
1091 sizeof(struct in_addr) > ipt->ipt_len) {
1092 code = (u_char *)&ipt->ipt_ptr -
1093 (u_char *)ip;
1094 goto bad;
1095 }
1096 ipaddr.sin_addr = dst;
1097 _ss = pserialize_read_enter();
1098 rcvif = m_get_rcvif(m, &_s);
1099 if (__predict_true(rcvif != NULL)) {
1100 ifa = ifaof_ifpforaddr(sintosa(&ipaddr),
1101 rcvif);
1102 }
1103 m_put_rcvif(rcvif, &_s);
1104 if (ifa == NULL) {
1105 pserialize_read_exit(_ss);
1106 break;
1107 }
1108 ia = ifatoia(ifa);
1109 bcopy(&ia->ia_addr.sin_addr,
1110 cp0, sizeof(struct in_addr));
1111 pserialize_read_exit(_ss);
1112 ipt->ipt_ptr += sizeof(struct in_addr);
1113 break;
1114 }
1115
1116 case IPOPT_TS_PRESPEC: {
1117 struct sockaddr_in ipaddr = {
1118 .sin_len = sizeof(ipaddr),
1119 .sin_family = AF_INET,
1120 };
1121
1122 if (ipt->ipt_ptr - 1 + sizeof(n_time) +
1123 sizeof(struct in_addr) > ipt->ipt_len) {
1124 code = (u_char *)&ipt->ipt_ptr -
1125 (u_char *)ip;
1126 goto bad;
1127 }
1128 memcpy(&ipaddr.sin_addr, cp0,
1129 sizeof(struct in_addr));
1130 s = pserialize_read_enter();
1131 ifa = ifa_ifwithaddr(sintosa(&ipaddr));
1132 if (ifa == NULL) {
1133 pserialize_read_exit(s);
1134 continue;
1135 }
1136 pserialize_read_exit(s);
1137 ipt->ipt_ptr += sizeof(struct in_addr);
1138 break;
1139 }
1140
1141 default:
1142 /* XXX can't take &ipt->ipt_flg */
1143 code = (u_char *)&ipt->ipt_ptr -
1144 (u_char *)ip + 1;
1145 goto bad;
1146 }
1147 ntime = iptime();
1148 cp0 = (u_char *) &ntime; /* XXX grumble, GCC... */
1149 memmove((char *)cp + ipt->ipt_ptr - 1, cp0,
1150 sizeof(n_time));
1151 ipt->ipt_ptr += sizeof(n_time);
1152 }
1153 }
1154 if (forward) {
1155 struct ifnet *rcvif;
1156 struct psref _psref;
1157
1158 if (ip_forwsrcrt == 0) {
1159 type = ICMP_UNREACH;
1160 code = ICMP_UNREACH_SRCFAIL;
1161 goto bad;
1162 }
1163
1164 rcvif = m_get_rcvif_psref(m, &_psref);
1165 if (__predict_false(rcvif == NULL)) {
1166 type = ICMP_UNREACH;
1167 code = ICMP_UNREACH_HOST;
1168 goto bad;
1169 }
1170 ip_forward(m, 1, rcvif);
1171 m_put_rcvif_psref(rcvif, &_psref);
1172 return true;
1173 }
1174 return false;
1175 bad:
1176 icmp_error(m, type, code, 0, 0);
1177 IP_STATINC(IP_STAT_BADOPTIONS);
1178 return true;
1179 }
1180
1181 /*
1182 * ip_rtaddr: given address of next destination (final or next hop),
1183 * return internet address info of interface to be used to get there.
1184 */
1185 static struct in_ifaddr *
1186 ip_rtaddr(struct in_addr dst, struct psref *psref)
1187 {
1188 struct rtentry *rt;
1189 union {
1190 struct sockaddr dst;
1191 struct sockaddr_in dst4;
1192 } u;
1193 struct route *ro;
1194
1195 sockaddr_in_init(&u.dst4, &dst, 0);
1196
1197 ro = percpu_getref(ipforward_rt_percpu);
1198 rt = rtcache_lookup(ro, &u.dst);
1199 if (rt == NULL) {
1200 percpu_putref(ipforward_rt_percpu);
1201 return NULL;
1202 }
1203
1204 ia4_acquire(ifatoia(rt->rt_ifa), psref);
1205 rtcache_unref(rt, ro);
1206 percpu_putref(ipforward_rt_percpu);
1207
1208 return ifatoia(rt->rt_ifa);
1209 }
1210
1211 /*
1212 * save_rte: save incoming source route for use in replies, to be picked
1213 * up later by ip_srcroute if the receiver is interested.
1214 */
1215 static void
1216 save_rte(struct mbuf *m, u_char *option, struct in_addr dst)
1217 {
1218 struct ip_srcrt *isr;
1219 struct m_tag *mtag;
1220 unsigned olen;
1221
1222 olen = option[IPOPT_OLEN];
1223 if (olen > sizeof(isr->isr_hdr) + sizeof(isr->isr_routes))
1224 return;
1225
1226 mtag = m_tag_get(PACKET_TAG_SRCROUTE, sizeof(*isr), M_NOWAIT);
1227 if (mtag == NULL)
1228 return;
1229 isr = (struct ip_srcrt *)(mtag + 1);
1230
1231 memcpy(isr->isr_hdr, option, olen);
1232 isr->isr_nhops = (olen - IPOPT_OFFSET - 1) / sizeof(struct in_addr);
1233 isr->isr_dst = dst;
1234 m_tag_prepend(m, mtag);
1235 }
1236
1237 /*
1238 * Retrieve incoming source route for use in replies,
1239 * in the same form used by setsockopt.
1240 * The first hop is placed before the options, will be removed later.
1241 */
1242 struct mbuf *
1243 ip_srcroute(struct mbuf *m0)
1244 {
1245 struct in_addr *p, *q;
1246 struct mbuf *m;
1247 struct ip_srcrt *isr;
1248 struct m_tag *mtag;
1249
1250 mtag = m_tag_find(m0, PACKET_TAG_SRCROUTE, NULL);
1251 if (mtag == NULL)
1252 return NULL;
1253 isr = (struct ip_srcrt *)(mtag + 1);
1254
1255 if (isr->isr_nhops == 0)
1256 return NULL;
1257
1258 m = m_get(M_DONTWAIT, MT_SOOPTS);
1259 if (m == NULL)
1260 return NULL;
1261
1262 MCLAIM(m, &inetdomain.dom_mowner);
1263 #define OPTSIZ (sizeof(isr->isr_nop) + sizeof(isr->isr_hdr))
1264
1265 /* length is (nhops+1)*sizeof(addr) + sizeof(nop + header) */
1266 m->m_len = (isr->isr_nhops + 1) * sizeof(struct in_addr) + OPTSIZ;
1267
1268 /*
1269 * First save first hop for return route
1270 */
1271 p = &(isr->isr_routes[isr->isr_nhops - 1]);
1272 *(mtod(m, struct in_addr *)) = *p--;
1273
1274 /*
1275 * Copy option fields and padding (nop) to mbuf.
1276 */
1277 isr->isr_nop = IPOPT_NOP;
1278 isr->isr_hdr[IPOPT_OFFSET] = IPOPT_MINOFF;
1279 memmove(mtod(m, char *) + sizeof(struct in_addr), &isr->isr_nop,
1280 OPTSIZ);
1281 q = (struct in_addr *)(mtod(m, char *) +
1282 sizeof(struct in_addr) + OPTSIZ);
1283 #undef OPTSIZ
1284 /*
1285 * Record return path as an IP source route,
1286 * reversing the path (pointers are now aligned).
1287 */
1288 while (p >= isr->isr_routes) {
1289 *q++ = *p--;
1290 }
1291 /*
1292 * Last hop goes to final destination.
1293 */
1294 *q = isr->isr_dst;
1295 m_tag_delete(m0, mtag);
1296 return m;
1297 }
1298
1299 const int inetctlerrmap[PRC_NCMDS] = {
1300 [PRC_MSGSIZE] = EMSGSIZE,
1301 [PRC_HOSTDEAD] = EHOSTDOWN,
1302 [PRC_HOSTUNREACH] = EHOSTUNREACH,
1303 [PRC_UNREACH_NET] = EHOSTUNREACH,
1304 [PRC_UNREACH_HOST] = EHOSTUNREACH,
1305 [PRC_UNREACH_PROTOCOL] = ECONNREFUSED,
1306 [PRC_UNREACH_PORT] = ECONNREFUSED,
1307 [PRC_UNREACH_SRCFAIL] = EHOSTUNREACH,
1308 [PRC_PARAMPROB] = ENOPROTOOPT,
1309 };
1310
1311 void
1312 ip_fasttimo(void)
1313 {
1314 if (ip_drainwanted) {
1315 ip_drain();
1316 ip_drainwanted = 0;
1317 }
1318 }
1319
1320 void
1321 ip_drainstub(void)
1322 {
1323 ip_drainwanted = 1;
1324 }
1325
1326 /*
1327 * Forward a packet. If some error occurs return the sender
1328 * an icmp packet. Note we can't always generate a meaningful
1329 * icmp message because icmp doesn't have a large enough repertoire
1330 * of codes and types.
1331 *
1332 * If not forwarding, just drop the packet. This could be confusing
1333 * if ipforwarding was zero but some routing protocol was advancing
1334 * us as a gateway to somewhere. However, we must let the routing
1335 * protocol deal with that.
1336 *
1337 * The srcrt parameter indicates whether the packet is being forwarded
1338 * via a source route.
1339 */
1340 static void
1341 ip_forward(struct mbuf *m, int srcrt, struct ifnet *rcvif)
1342 {
1343 struct ip *ip = mtod(m, struct ip *);
1344 struct rtentry *rt;
1345 int error, type = 0, code = 0, destmtu = 0;
1346 struct mbuf *mcopy;
1347 n_long dest;
1348 union {
1349 struct sockaddr dst;
1350 struct sockaddr_in dst4;
1351 } u;
1352 uint64_t *ips;
1353 struct route *ro;
1354
1355 KASSERTMSG(cpu_softintr_p(), "ip_forward: not in the software "
1356 "interrupt handler; synchronization assumptions violated");
1357
1358 /*
1359 * We are now in the output path.
1360 */
1361 MCLAIM(m, &ip_tx_mowner);
1362
1363 /*
1364 * Clear any in-bound checksum flags for this packet.
1365 */
1366 m->m_pkthdr.csum_flags = 0;
1367
1368 dest = 0;
1369 if (m->m_flags & (M_BCAST|M_MCAST) || in_canforward(ip->ip_dst) == 0) {
1370 IP_STATINC(IP_STAT_CANTFORWARD);
1371 m_freem(m);
1372 return;
1373 }
1374
1375 if (ip->ip_ttl <= IPTTLDEC) {
1376 icmp_error(m, ICMP_TIMXCEED, ICMP_TIMXCEED_INTRANS, dest, 0);
1377 return;
1378 }
1379
1380 sockaddr_in_init(&u.dst4, &ip->ip_dst, 0);
1381
1382 ro = percpu_getref(ipforward_rt_percpu);
1383 rt = rtcache_lookup(ro, &u.dst);
1384 if (rt == NULL) {
1385 percpu_putref(ipforward_rt_percpu);
1386 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_NET, dest, 0);
1387 return;
1388 }
1389
1390 /*
1391 * Save at most 68 bytes of the packet in case
1392 * we need to generate an ICMP message to the src.
1393 * Pullup to avoid sharing mbuf cluster between m and mcopy.
1394 */
1395 mcopy = m_copym(m, 0, imin(ntohs(ip->ip_len), 68), M_DONTWAIT);
1396 if (mcopy)
1397 mcopy = m_pullup(mcopy, ip->ip_hl << 2);
1398
1399 ip->ip_ttl -= IPTTLDEC;
1400
1401 /*
1402 * If forwarding packet using same interface that it came in on,
1403 * perhaps should send a redirect to sender to shortcut a hop.
1404 * Only send redirect if source is sending directly to us,
1405 * and if packet was not source routed (or has any options).
1406 * Also, don't send redirect if forwarding using a default route
1407 * or a route modified by a redirect.
1408 */
1409 if (rt->rt_ifp == rcvif &&
1410 (rt->rt_flags & (RTF_DYNAMIC|RTF_MODIFIED)) == 0 &&
1411 !in_nullhost(satocsin(rt_getkey(rt))->sin_addr) &&
1412 ipsendredirects && !srcrt) {
1413 if (rt->rt_ifa &&
1414 (ip->ip_src.s_addr & ifatoia(rt->rt_ifa)->ia_subnetmask) ==
1415 ifatoia(rt->rt_ifa)->ia_subnet) {
1416 if (rt->rt_flags & RTF_GATEWAY)
1417 dest = satosin(rt->rt_gateway)->sin_addr.s_addr;
1418 else
1419 dest = ip->ip_dst.s_addr;
1420 /*
1421 * Router requirements says to only send host
1422 * redirects.
1423 */
1424 type = ICMP_REDIRECT;
1425 code = ICMP_REDIRECT_HOST;
1426 }
1427 }
1428 rtcache_unref(rt, ro);
1429
1430 error = ip_output(m, NULL, ro,
1431 (IP_FORWARDING | (ip_directedbcast ? IP_ALLOWBROADCAST : 0)),
1432 NULL, NULL);
1433
1434 if (error) {
1435 IP_STATINC(IP_STAT_CANTFORWARD);
1436 goto error;
1437 }
1438
1439 ips = IP_STAT_GETREF();
1440 ips[IP_STAT_FORWARD]++;
1441
1442 if (type) {
1443 ips[IP_STAT_REDIRECTSENT]++;
1444 IP_STAT_PUTREF();
1445 goto redirect;
1446 }
1447
1448 IP_STAT_PUTREF();
1449 if (mcopy) {
1450 #ifdef GATEWAY
1451 if (mcopy->m_flags & M_CANFASTFWD)
1452 ipflow_create(ro, mcopy);
1453 #endif
1454 m_freem(mcopy);
1455 }
1456
1457 percpu_putref(ipforward_rt_percpu);
1458 return;
1459
1460 redirect:
1461 error:
1462 if (mcopy == NULL) {
1463 percpu_putref(ipforward_rt_percpu);
1464 return;
1465 }
1466
1467 switch (error) {
1468
1469 case 0: /* forwarded, but need redirect */
1470 /* type, code set above */
1471 break;
1472
1473 case ENETUNREACH: /* shouldn't happen, checked above */
1474 case EHOSTUNREACH:
1475 case ENETDOWN:
1476 case EHOSTDOWN:
1477 default:
1478 type = ICMP_UNREACH;
1479 code = ICMP_UNREACH_HOST;
1480 break;
1481
1482 case EMSGSIZE:
1483 type = ICMP_UNREACH;
1484 code = ICMP_UNREACH_NEEDFRAG;
1485
1486 if ((rt = rtcache_validate(ro)) != NULL) {
1487 destmtu = rt->rt_ifp->if_mtu;
1488 rtcache_unref(rt, ro);
1489 }
1490 #ifdef IPSEC
1491 if (ipsec_used)
1492 (void)ipsec4_forward(mcopy, &destmtu);
1493 #endif
1494 IP_STATINC(IP_STAT_CANTFRAG);
1495 break;
1496
1497 case ENOBUFS:
1498 /*
1499 * Do not generate ICMP_SOURCEQUENCH as required in RFC 1812,
1500 * Requirements for IP Version 4 Routers. Source quench can
1501 * big problem under DoS attacks or if the underlying
1502 * interface is rate-limited.
1503 */
1504 if (mcopy)
1505 m_freem(mcopy);
1506 percpu_putref(ipforward_rt_percpu);
1507 return;
1508 }
1509 icmp_error(mcopy, type, code, dest, destmtu);
1510 percpu_putref(ipforward_rt_percpu);
1511 }
1512
1513 void
1514 ip_savecontrol(struct inpcb *inp, struct mbuf **mp, struct ip *ip,
1515 struct mbuf *m)
1516 {
1517 struct socket *so = inp->inp_socket;
1518 int inpflags = inp->inp_flags;
1519
1520 if (SOOPT_TIMESTAMP(so->so_options))
1521 mp = sbsavetimestamp(so->so_options, m, mp);
1522
1523 if (inpflags & INP_RECVDSTADDR) {
1524 *mp = sbcreatecontrol(&ip->ip_dst,
1525 sizeof(struct in_addr), IP_RECVDSTADDR, IPPROTO_IP);
1526 if (*mp)
1527 mp = &(*mp)->m_next;
1528 }
1529
1530 if (inpflags & INP_RECVTTL) {
1531 *mp = sbcreatecontrol(&ip->ip_ttl,
1532 sizeof(uint8_t), IP_RECVTTL, IPPROTO_IP);
1533 if (*mp)
1534 mp = &(*mp)->m_next;
1535 }
1536
1537 struct psref psref;
1538 ifnet_t *ifp = m_get_rcvif_psref(m, &psref);
1539 if (__predict_false(ifp == NULL)) {
1540 #ifdef DIAGNOSTIC
1541 printf("%s: missing receive interface\n", __func__);
1542 #endif
1543 return; /* XXX should report error? */
1544 }
1545
1546 if (inpflags & INP_RECVPKTINFO) {
1547 struct in_pktinfo ipi;
1548 ipi.ipi_addr = ip->ip_src;
1549 ipi.ipi_ifindex = ifp->if_index;
1550 *mp = sbcreatecontrol(&ipi,
1551 sizeof(ipi), IP_RECVPKTINFO, IPPROTO_IP);
1552 if (*mp)
1553 mp = &(*mp)->m_next;
1554 }
1555 if (inpflags & INP_PKTINFO) {
1556 struct in_pktinfo ipi;
1557 ipi.ipi_addr = ip->ip_dst;
1558 ipi.ipi_ifindex = ifp->if_index;
1559 *mp = sbcreatecontrol(&ipi,
1560 sizeof(ipi), IP_PKTINFO, IPPROTO_IP);
1561 if (*mp)
1562 mp = &(*mp)->m_next;
1563 }
1564 if (inpflags & INP_RECVIF) {
1565 struct sockaddr_dl sdl;
1566
1567 sockaddr_dl_init(&sdl, sizeof(sdl), ifp->if_index, 0, NULL, 0,
1568 NULL, 0);
1569 *mp = sbcreatecontrol(&sdl, sdl.sdl_len, IP_RECVIF, IPPROTO_IP);
1570 if (*mp)
1571 mp = &(*mp)->m_next;
1572 }
1573 m_put_rcvif_psref(ifp, &psref);
1574 }
1575
1576 /*
1577 * sysctl helper routine for net.inet.ip.forwsrcrt.
1578 */
1579 static int
1580 sysctl_net_inet_ip_forwsrcrt(SYSCTLFN_ARGS)
1581 {
1582 int error, tmp;
1583 struct sysctlnode node;
1584
1585 node = *rnode;
1586 tmp = ip_forwsrcrt;
1587 node.sysctl_data = &tmp;
1588 error = sysctl_lookup(SYSCTLFN_CALL(&node));
1589 if (error || newp == NULL)
1590 return (error);
1591
1592 error = kauth_authorize_network(l->l_cred, KAUTH_NETWORK_FORWSRCRT,
1593 0, NULL, NULL, NULL);
1594 if (error)
1595 return (error);
1596
1597 ip_forwsrcrt = tmp;
1598
1599 return (0);
1600 }
1601
1602 /*
1603 * sysctl helper routine for net.inet.ip.mtudisctimeout. checks the
1604 * range of the new value and tweaks timers if it changes.
1605 */
1606 static int
1607 sysctl_net_inet_ip_pmtudto(SYSCTLFN_ARGS)
1608 {
1609 int error, tmp;
1610 struct sysctlnode node;
1611
1612 icmp_mtudisc_lock();
1613
1614 node = *rnode;
1615 tmp = ip_mtudisc_timeout;
1616 node.sysctl_data = &tmp;
1617 error = sysctl_lookup(SYSCTLFN_CALL(&node));
1618 if (error || newp == NULL)
1619 goto out;
1620 if (tmp < 0) {
1621 error = EINVAL;
1622 goto out;
1623 }
1624
1625 ip_mtudisc_timeout = tmp;
1626 rt_timer_queue_change(ip_mtudisc_timeout_q, ip_mtudisc_timeout);
1627 error = 0;
1628 out:
1629 icmp_mtudisc_unlock();
1630 return error;
1631 }
1632
1633 static int
1634 sysctl_net_inet_ip_stats(SYSCTLFN_ARGS)
1635 {
1636
1637 return (NETSTAT_SYSCTL(ipstat_percpu, IP_NSTATS));
1638 }
1639
1640 static void
1641 sysctl_net_inet_ip_setup(struct sysctllog **clog)
1642 {
1643 sysctl_createv(clog, 0, NULL, NULL,
1644 CTLFLAG_PERMANENT,
1645 CTLTYPE_NODE, "inet",
1646 SYSCTL_DESCR("PF_INET related settings"),
1647 NULL, 0, NULL, 0,
1648 CTL_NET, PF_INET, CTL_EOL);
1649 sysctl_createv(clog, 0, NULL, NULL,
1650 CTLFLAG_PERMANENT,
1651 CTLTYPE_NODE, "ip",
1652 SYSCTL_DESCR("IPv4 related settings"),
1653 NULL, 0, NULL, 0,
1654 CTL_NET, PF_INET, IPPROTO_IP, CTL_EOL);
1655
1656 sysctl_createv(clog, 0, NULL, NULL,
1657 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1658 CTLTYPE_INT, "forwarding",
1659 SYSCTL_DESCR("Enable forwarding of INET datagrams"),
1660 NULL, 0, &ipforwarding, 0,
1661 CTL_NET, PF_INET, IPPROTO_IP,
1662 IPCTL_FORWARDING, CTL_EOL);
1663 sysctl_createv(clog, 0, NULL, NULL,
1664 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1665 CTLTYPE_INT, "redirect",
1666 SYSCTL_DESCR("Enable sending of ICMP redirect messages"),
1667 NULL, 0, &ipsendredirects, 0,
1668 CTL_NET, PF_INET, IPPROTO_IP,
1669 IPCTL_SENDREDIRECTS, CTL_EOL);
1670 sysctl_createv(clog, 0, NULL, NULL,
1671 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1672 CTLTYPE_INT, "ttl",
1673 SYSCTL_DESCR("Default TTL for an INET datagram"),
1674 NULL, 0, &ip_defttl, 0,
1675 CTL_NET, PF_INET, IPPROTO_IP,
1676 IPCTL_DEFTTL, CTL_EOL);
1677 #ifdef IPCTL_DEFMTU
1678 sysctl_createv(clog, 0, NULL, NULL,
1679 CTLFLAG_PERMANENT /* |CTLFLAG_READWRITE? */,
1680 CTLTYPE_INT, "mtu",
1681 SYSCTL_DESCR("Default MTA for an INET route"),
1682 NULL, 0, &ip_mtu, 0,
1683 CTL_NET, PF_INET, IPPROTO_IP,
1684 IPCTL_DEFMTU, CTL_EOL);
1685 #endif /* IPCTL_DEFMTU */
1686 sysctl_createv(clog, 0, NULL, NULL,
1687 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1688 CTLTYPE_INT, "forwsrcrt",
1689 SYSCTL_DESCR("Enable forwarding of source-routed "
1690 "datagrams"),
1691 sysctl_net_inet_ip_forwsrcrt, 0, &ip_forwsrcrt, 0,
1692 CTL_NET, PF_INET, IPPROTO_IP,
1693 IPCTL_FORWSRCRT, CTL_EOL);
1694 sysctl_createv(clog, 0, NULL, NULL,
1695 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1696 CTLTYPE_INT, "directed-broadcast",
1697 SYSCTL_DESCR("Enable forwarding of broadcast datagrams"),
1698 NULL, 0, &ip_directedbcast, 0,
1699 CTL_NET, PF_INET, IPPROTO_IP,
1700 IPCTL_DIRECTEDBCAST, CTL_EOL);
1701 sysctl_createv(clog, 0, NULL, NULL,
1702 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1703 CTLTYPE_INT, "allowsrcrt",
1704 SYSCTL_DESCR("Accept source-routed datagrams"),
1705 NULL, 0, &ip_allowsrcrt, 0,
1706 CTL_NET, PF_INET, IPPROTO_IP,
1707 IPCTL_ALLOWSRCRT, CTL_EOL);
1708
1709 sysctl_createv(clog, 0, NULL, NULL,
1710 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1711 CTLTYPE_INT, "mtudisc",
1712 SYSCTL_DESCR("Use RFC1191 Path MTU Discovery"),
1713 NULL, 0, &ip_mtudisc, 0,
1714 CTL_NET, PF_INET, IPPROTO_IP,
1715 IPCTL_MTUDISC, CTL_EOL);
1716 sysctl_createv(clog, 0, NULL, NULL,
1717 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1718 CTLTYPE_INT, "anonportmin",
1719 SYSCTL_DESCR("Lowest ephemeral port number to assign"),
1720 sysctl_net_inet_ip_ports, 0, &anonportmin, 0,
1721 CTL_NET, PF_INET, IPPROTO_IP,
1722 IPCTL_ANONPORTMIN, CTL_EOL);
1723 sysctl_createv(clog, 0, NULL, NULL,
1724 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1725 CTLTYPE_INT, "anonportmax",
1726 SYSCTL_DESCR("Highest ephemeral port number to assign"),
1727 sysctl_net_inet_ip_ports, 0, &anonportmax, 0,
1728 CTL_NET, PF_INET, IPPROTO_IP,
1729 IPCTL_ANONPORTMAX, CTL_EOL);
1730 sysctl_createv(clog, 0, NULL, NULL,
1731 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1732 CTLTYPE_INT, "mtudisctimeout",
1733 SYSCTL_DESCR("Lifetime of a Path MTU Discovered route"),
1734 sysctl_net_inet_ip_pmtudto, 0, (void *)&ip_mtudisc_timeout, 0,
1735 CTL_NET, PF_INET, IPPROTO_IP,
1736 IPCTL_MTUDISCTIMEOUT, CTL_EOL);
1737 #ifndef IPNOPRIVPORTS
1738 sysctl_createv(clog, 0, NULL, NULL,
1739 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1740 CTLTYPE_INT, "lowportmin",
1741 SYSCTL_DESCR("Lowest privileged ephemeral port number "
1742 "to assign"),
1743 sysctl_net_inet_ip_ports, 0, &lowportmin, 0,
1744 CTL_NET, PF_INET, IPPROTO_IP,
1745 IPCTL_LOWPORTMIN, CTL_EOL);
1746 sysctl_createv(clog, 0, NULL, NULL,
1747 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1748 CTLTYPE_INT, "lowportmax",
1749 SYSCTL_DESCR("Highest privileged ephemeral port number "
1750 "to assign"),
1751 sysctl_net_inet_ip_ports, 0, &lowportmax, 0,
1752 CTL_NET, PF_INET, IPPROTO_IP,
1753 IPCTL_LOWPORTMAX, CTL_EOL);
1754 #endif /* IPNOPRIVPORTS */
1755 #if NGRE > 0
1756 sysctl_createv(clog, 0, NULL, NULL,
1757 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1758 CTLTYPE_INT, "grettl",
1759 SYSCTL_DESCR("Default TTL for a gre tunnel datagram"),
1760 NULL, 0, &ip_gre_ttl, 0,
1761 CTL_NET, PF_INET, IPPROTO_IP,
1762 IPCTL_GRE_TTL, CTL_EOL);
1763 #endif /* NGRE */
1764 sysctl_createv(clog, 0, NULL, NULL,
1765 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1766 CTLTYPE_INT, "checkinterface",
1767 SYSCTL_DESCR("Enable receive side of Strong ES model "
1768 "from RFC1122"),
1769 NULL, 0, &ip_checkinterface, 0,
1770 CTL_NET, PF_INET, IPPROTO_IP,
1771 IPCTL_CHECKINTERFACE, CTL_EOL);
1772 sysctl_createv(clog, 0, NULL, NULL,
1773 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1774 CTLTYPE_INT, "random_id",
1775 SYSCTL_DESCR("Assign random ip_id values"),
1776 NULL, 0, &ip_do_randomid, 0,
1777 CTL_NET, PF_INET, IPPROTO_IP,
1778 IPCTL_RANDOMID, CTL_EOL);
1779 sysctl_createv(clog, 0, NULL, NULL,
1780 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1781 CTLTYPE_INT, "do_loopback_cksum",
1782 SYSCTL_DESCR("Perform IP checksum on loopback"),
1783 NULL, 0, &ip_do_loopback_cksum, 0,
1784 CTL_NET, PF_INET, IPPROTO_IP,
1785 IPCTL_LOOPBACKCKSUM, CTL_EOL);
1786 sysctl_createv(clog, 0, NULL, NULL,
1787 CTLFLAG_PERMANENT,
1788 CTLTYPE_STRUCT, "stats",
1789 SYSCTL_DESCR("IP statistics"),
1790 sysctl_net_inet_ip_stats, 0, NULL, 0,
1791 CTL_NET, PF_INET, IPPROTO_IP, IPCTL_STATS,
1792 CTL_EOL);
1793 #if NARP
1794 sysctl_createv(clog, 0, NULL, NULL,
1795 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1796 CTLTYPE_INT, "dad_count",
1797 SYSCTL_DESCR("Number of Duplicate Address Detection "
1798 "probes to send"),
1799 NULL, 0, &ip_dad_count, 0,
1800 CTL_NET, PF_INET, IPPROTO_IP,
1801 IPCTL_DAD_COUNT, CTL_EOL);
1802 #endif
1803
1804 /* anonportalgo RFC6056 subtree */
1805 const struct sysctlnode *portalgo_node;
1806 sysctl_createv(clog, 0, NULL, &portalgo_node,
1807 CTLFLAG_PERMANENT,
1808 CTLTYPE_NODE, "anonportalgo",
1809 SYSCTL_DESCR("Anonymous Port Algorithm Selection (RFC 6056)"),
1810 NULL, 0, NULL, 0,
1811 CTL_NET, PF_INET, IPPROTO_IP, CTL_CREATE, CTL_EOL);
1812 sysctl_createv(clog, 0, &portalgo_node, NULL,
1813 CTLFLAG_PERMANENT,
1814 CTLTYPE_STRING, "available",
1815 SYSCTL_DESCR("available algorithms"),
1816 sysctl_portalgo_available, 0, NULL, PORTALGO_MAXLEN,
1817 CTL_CREATE, CTL_EOL);
1818 sysctl_createv(clog, 0, &portalgo_node, NULL,
1819 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1820 CTLTYPE_STRING, "selected",
1821 SYSCTL_DESCR("selected algorithm"),
1822 sysctl_portalgo_selected4, 0, NULL, PORTALGO_MAXLEN,
1823 CTL_CREATE, CTL_EOL);
1824 sysctl_createv(clog, 0, &portalgo_node, NULL,
1825 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1826 CTLTYPE_STRUCT, "reserve",
1827 SYSCTL_DESCR("bitmap of reserved ports"),
1828 sysctl_portalgo_reserve4, 0, NULL, 0,
1829 CTL_CREATE, CTL_EOL);
1830 }
1831
1832 void
1833 ip_statinc(u_int stat)
1834 {
1835
1836 KASSERT(stat < IP_NSTATS);
1837 IP_STATINC(stat);
1838 }
1839