ip_input.c revision 1.355.2.5 1 /* $NetBSD: ip_input.c,v 1.355.2.5 2018/02/26 13:32:01 martin 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 1.355.2.5 2018/02/26 13:32:01 martin Exp $");
95
96 #ifdef _KERNEL_OPT
97 #include "opt_inet.h"
98 #include "opt_compat_netbsd.h"
99 #include "opt_gateway.h"
100 #include "opt_ipsec.h"
101 #include "opt_mrouting.h"
102 #include "opt_mbuftrace.h"
103 #include "opt_inet_csum.h"
104 #include "opt_net_mpsafe.h"
105 #endif
106
107 #include "arp.h"
108
109 #include <sys/param.h>
110 #include <sys/systm.h>
111 #include <sys/cpu.h>
112 #include <sys/mbuf.h>
113 #include <sys/domain.h>
114 #include <sys/protosw.h>
115 #include <sys/socket.h>
116 #include <sys/socketvar.h>
117 #include <sys/errno.h>
118 #include <sys/time.h>
119 #include <sys/kernel.h>
120 #include <sys/pool.h>
121 #include <sys/sysctl.h>
122 #include <sys/kauth.h>
123
124 #include <net/if.h>
125 #include <net/if_dl.h>
126 #include <net/route.h>
127 #include <net/pktqueue.h>
128 #include <net/pfil.h>
129
130 #include <netinet/in.h>
131 #include <netinet/in_systm.h>
132 #include <netinet/ip.h>
133 #include <netinet/in_pcb.h>
134 #include <netinet/in_proto.h>
135 #include <netinet/in_var.h>
136 #include <netinet/ip_var.h>
137 #include <netinet/ip_private.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 #include <netinet/portalgo.h>
149
150 #ifdef IPSEC
151 #include <netipsec/ipsec.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 0 /* forward source-routed packets */
166 #endif
167 #ifndef IPALLOWSRCRT
168 #define IPALLOWSRCRT 0 /* 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 #ifdef COMPAT_50
178 #include <compat/sys/time.h>
179 #include <compat/sys/socket.h>
180 #endif
181
182 /*
183 * Note: DIRECTED_BROADCAST is handled this way so that previous
184 * configuration using this option will Just Work.
185 */
186 #ifndef IPDIRECTEDBCAST
187 #ifdef DIRECTED_BROADCAST
188 #define IPDIRECTEDBCAST 1
189 #else
190 #define IPDIRECTEDBCAST 0
191 #endif /* DIRECTED_BROADCAST */
192 #endif /* IPDIRECTEDBCAST */
193 int ipforwarding = IPFORWARDING;
194 int ipsendredirects = IPSENDREDIRECTS;
195 int ip_defttl = IPDEFTTL;
196 int ip_forwsrcrt = IPFORWSRCRT;
197 int ip_directedbcast = IPDIRECTEDBCAST;
198 int ip_allowsrcrt = IPALLOWSRCRT;
199 int ip_mtudisc = IPMTUDISC;
200 int ip_mtudisc_timeout = IPMTUDISCTIMEOUT;
201 #ifdef DIAGNOSTIC
202 int ipprintfs = 0;
203 #endif
204
205 int ip_do_randomid = 0;
206
207 /*
208 * XXX - Setting ip_checkinterface mostly implements the receive side of
209 * the Strong ES model described in RFC 1122, but since the routing table
210 * and transmit implementation do not implement the Strong ES model,
211 * setting this to 1 results in an odd hybrid.
212 *
213 * XXX - ip_checkinterface currently must be disabled if you use ipnat
214 * to translate the destination address to another local interface.
215 *
216 * XXX - ip_checkinterface must be disabled if you add IP aliases
217 * to the loopback interface instead of the interface where the
218 * packets for those addresses are received.
219 */
220 static int ip_checkinterface __read_mostly = 0;
221
222 struct rttimer_queue *ip_mtudisc_timeout_q = NULL;
223
224 pktqueue_t * ip_pktq __read_mostly;
225 pfil_head_t * inet_pfil_hook __read_mostly;
226 ipid_state_t * ip_ids __read_mostly;
227 percpu_t * ipstat_percpu __read_mostly;
228
229 static percpu_t *ipforward_rt_percpu __cacheline_aligned;
230
231 uint16_t ip_id;
232
233 #ifdef INET_CSUM_COUNTERS
234 #include <sys/device.h>
235
236 struct evcnt ip_hwcsum_bad = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
237 NULL, "inet", "hwcsum bad");
238 struct evcnt ip_hwcsum_ok = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
239 NULL, "inet", "hwcsum ok");
240 struct evcnt ip_swcsum = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
241 NULL, "inet", "swcsum");
242
243 #define INET_CSUM_COUNTER_INCR(ev) (ev)->ev_count++
244
245 EVCNT_ATTACH_STATIC(ip_hwcsum_bad);
246 EVCNT_ATTACH_STATIC(ip_hwcsum_ok);
247 EVCNT_ATTACH_STATIC(ip_swcsum);
248
249 #else
250
251 #define INET_CSUM_COUNTER_INCR(ev) /* nothing */
252
253 #endif /* INET_CSUM_COUNTERS */
254
255 /*
256 * Used to save the IP options in case a protocol wants to respond
257 * to an incoming packet over the same route if the packet got here
258 * using IP source routing. This allows connection establishment and
259 * maintenance when the remote end is on a network that is not known
260 * to us.
261 */
262 struct ip_srcrt {
263 int isr_nhops; /* number of hops */
264 struct in_addr isr_dst; /* final destination */
265 char isr_nop; /* one NOP to align */
266 char isr_hdr[IPOPT_OFFSET + 1]; /* OPTVAL, OLEN & OFFSET */
267 struct in_addr isr_routes[MAX_IPOPTLEN/sizeof(struct in_addr)];
268 };
269
270 static int ip_drainwanted;
271
272 static void save_rte(struct mbuf *, u_char *, struct in_addr);
273
274 #ifdef MBUFTRACE
275 struct mowner ip_rx_mowner = MOWNER_INIT("internet", "rx");
276 struct mowner ip_tx_mowner = MOWNER_INIT("internet", "tx");
277 #endif
278
279 static void ipintr(void *);
280 static void ip_input(struct mbuf *);
281 static void ip_forward(struct mbuf *, int, struct ifnet *);
282 static bool ip_dooptions(struct mbuf *);
283 static struct in_ifaddr *ip_rtaddr(struct in_addr, struct psref *);
284 static void sysctl_net_inet_ip_setup(struct sysctllog **);
285
286 static struct in_ifaddr *ip_match_our_address(struct ifnet *, struct ip *,
287 int *);
288 static struct in_ifaddr *ip_match_our_address_broadcast(struct ifnet *,
289 struct ip *);
290
291 #ifdef NET_MPSAFE
292 #define SOFTNET_LOCK() mutex_enter(softnet_lock)
293 #define SOFTNET_UNLOCK() mutex_exit(softnet_lock)
294 #else
295 #define SOFTNET_LOCK() KASSERT(mutex_owned(softnet_lock))
296 #define SOFTNET_UNLOCK() KASSERT(mutex_owned(softnet_lock))
297 #endif
298
299 /*
300 * IP initialization: fill in IP protocol switch table.
301 * All protocols not implemented in kernel go to raw IP protocol handler.
302 */
303 void
304 ip_init(void)
305 {
306 const struct protosw *pr;
307
308 in_init();
309 sysctl_net_inet_ip_setup(NULL);
310
311 pr = pffindproto(PF_INET, IPPROTO_RAW, SOCK_RAW);
312 KASSERT(pr != NULL);
313
314 ip_pktq = pktq_create(IFQ_MAXLEN, ipintr, NULL);
315 KASSERT(ip_pktq != NULL);
316
317 for (u_int i = 0; i < IPPROTO_MAX; i++) {
318 ip_protox[i] = pr - inetsw;
319 }
320 for (pr = inetdomain.dom_protosw;
321 pr < inetdomain.dom_protoswNPROTOSW; pr++)
322 if (pr->pr_domain->dom_family == PF_INET &&
323 pr->pr_protocol && pr->pr_protocol != IPPROTO_RAW)
324 ip_protox[pr->pr_protocol] = pr - inetsw;
325
326 ip_reass_init();
327
328 ip_ids = ip_id_init();
329 ip_id = time_uptime & 0xfffff;
330
331 #ifdef GATEWAY
332 ipflow_init();
333 #endif
334
335 /* Register our Packet Filter hook. */
336 inet_pfil_hook = pfil_head_create(PFIL_TYPE_AF, (void *)AF_INET);
337 KASSERT(inet_pfil_hook != NULL);
338
339 #ifdef MBUFTRACE
340 MOWNER_ATTACH(&ip_tx_mowner);
341 MOWNER_ATTACH(&ip_rx_mowner);
342 #endif /* MBUFTRACE */
343
344 ipstat_percpu = percpu_alloc(sizeof(uint64_t) * IP_NSTATS);
345 ipforward_rt_percpu = percpu_alloc(sizeof(struct route));
346 ip_mtudisc_timeout_q = rt_timer_queue_create(ip_mtudisc_timeout);
347 }
348
349 static struct in_ifaddr *
350 ip_match_our_address(struct ifnet *ifp, struct ip *ip, int *downmatch)
351 {
352 struct in_ifaddr *ia = NULL;
353 int checkif;
354
355 /*
356 * Enable a consistency check between the destination address
357 * and the arrival interface for a unicast packet (the RFC 1122
358 * strong ES model) if IP forwarding is disabled and the packet
359 * is not locally generated.
360 *
361 * XXX - Checking also should be disabled if the destination
362 * address is ipnat'ed to a different interface.
363 *
364 * XXX - Checking is incompatible with IP aliases added
365 * to the loopback interface instead of the interface where
366 * the packets are received.
367 *
368 * XXX - We need to add a per ifaddr flag for this so that
369 * we get finer grain control.
370 */
371 checkif = ip_checkinterface && (ipforwarding == 0) &&
372 (ifp->if_flags & IFF_LOOPBACK) == 0;
373
374 IN_ADDRHASH_READER_FOREACH(ia, ip->ip_dst.s_addr) {
375 if (in_hosteq(ia->ia_addr.sin_addr, ip->ip_dst)) {
376 if (ia->ia4_flags & IN_IFF_NOTREADY)
377 continue;
378 if (checkif && ia->ia_ifp != ifp)
379 continue;
380 if ((ia->ia_ifp->if_flags & IFF_UP) == 0) {
381 (*downmatch)++;
382 continue;
383 }
384 if (ia->ia4_flags & IN_IFF_DETACHED &&
385 (ifp->if_flags & IFF_LOOPBACK) == 0)
386 continue;
387 break;
388 }
389 }
390
391 return ia;
392 }
393
394 static struct in_ifaddr *
395 ip_match_our_address_broadcast(struct ifnet *ifp, struct ip *ip)
396 {
397 struct in_ifaddr *ia = NULL;
398 struct ifaddr *ifa;
399
400 IFADDR_READER_FOREACH(ifa, ifp) {
401 if (ifa->ifa_addr->sa_family != AF_INET)
402 continue;
403 ia = ifatoia(ifa);
404 if (ia->ia4_flags & IN_IFF_NOTREADY)
405 continue;
406 if (ia->ia4_flags & IN_IFF_DETACHED &&
407 (ifp->if_flags & IFF_LOOPBACK) == 0)
408 continue;
409 if (in_hosteq(ip->ip_dst, ia->ia_broadaddr.sin_addr) ||
410 in_hosteq(ip->ip_dst, ia->ia_netbroadcast) ||
411 /*
412 * Look for all-0's host part (old broadcast addr),
413 * either for subnet or net.
414 */
415 ip->ip_dst.s_addr == ia->ia_subnet ||
416 ip->ip_dst.s_addr == ia->ia_net)
417 goto matched;
418 /*
419 * An interface with IP address zero accepts
420 * all packets that arrive on that interface.
421 */
422 if (in_nullhost(ia->ia_addr.sin_addr))
423 goto matched;
424 }
425 ia = NULL;
426
427 matched:
428 return ia;
429 }
430
431 /*
432 * IP software interrupt routine.
433 */
434 static void
435 ipintr(void *arg __unused)
436 {
437 struct mbuf *m;
438
439 KASSERT(cpu_softintr_p());
440
441 SOFTNET_KERNEL_LOCK_UNLESS_NET_MPSAFE();
442 while ((m = pktq_dequeue(ip_pktq)) != NULL) {
443 ip_input(m);
444 }
445 SOFTNET_KERNEL_UNLOCK_UNLESS_NET_MPSAFE();
446 }
447
448 /*
449 * IP input routine. Checksum and byte swap header. If fragmented
450 * try to reassemble. Process options. Pass to next level.
451 */
452 static void
453 ip_input(struct mbuf *m)
454 {
455 struct ip *ip = NULL;
456 struct in_ifaddr *ia = NULL;
457 int hlen = 0, len;
458 int downmatch;
459 int srcrt = 0;
460 ifnet_t *ifp;
461 struct psref psref;
462 int s;
463
464 KASSERTMSG(cpu_softintr_p(), "ip_input: not in the software "
465 "interrupt handler; synchronization assumptions violated");
466
467 MCLAIM(m, &ip_rx_mowner);
468 KASSERT((m->m_flags & M_PKTHDR) != 0);
469
470 ifp = m_get_rcvif_psref(m, &psref);
471 if (__predict_false(ifp == NULL))
472 goto out;
473
474 /*
475 * If no IP addresses have been set yet but the interfaces
476 * are receiving, can't do anything with incoming packets yet.
477 * Note: we pre-check without locks held.
478 */
479 if (IN_ADDRLIST_READER_EMPTY())
480 goto out;
481 IP_STATINC(IP_STAT_TOTAL);
482
483 /*
484 * If the IP header is not aligned, slurp it up into a new
485 * mbuf with space for link headers, in the event we forward
486 * it. Otherwise, if it is aligned, make sure the entire
487 * base IP header is in the first mbuf of the chain.
488 */
489 if (IP_HDR_ALIGNED_P(mtod(m, void *)) == 0) {
490 if ((m = m_copyup(m, sizeof(struct ip),
491 (max_linkhdr + 3) & ~3)) == NULL) {
492 /* XXXJRT new stat, please */
493 IP_STATINC(IP_STAT_TOOSMALL);
494 goto out;
495 }
496 } else if (__predict_false(m->m_len < sizeof (struct ip))) {
497 if ((m = m_pullup(m, sizeof (struct ip))) == NULL) {
498 IP_STATINC(IP_STAT_TOOSMALL);
499 goto out;
500 }
501 }
502 ip = mtod(m, struct ip *);
503 if (ip->ip_v != IPVERSION) {
504 IP_STATINC(IP_STAT_BADVERS);
505 goto out;
506 }
507 hlen = ip->ip_hl << 2;
508 if (hlen < sizeof(struct ip)) { /* minimum header length */
509 IP_STATINC(IP_STAT_BADHLEN);
510 goto out;
511 }
512 if (hlen > m->m_len) {
513 if ((m = m_pullup(m, hlen)) == NULL) {
514 IP_STATINC(IP_STAT_BADHLEN);
515 goto out;
516 }
517 ip = mtod(m, struct ip *);
518 }
519
520 /*
521 * RFC1122: packets with a multicast source address are
522 * not allowed.
523 */
524 if (IN_MULTICAST(ip->ip_src.s_addr)) {
525 IP_STATINC(IP_STAT_BADADDR);
526 goto out;
527 }
528
529 /* 127/8 must not appear on wire - RFC1122 */
530 if ((ntohl(ip->ip_dst.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET ||
531 (ntohl(ip->ip_src.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET) {
532 if ((ifp->if_flags & IFF_LOOPBACK) == 0) {
533 IP_STATINC(IP_STAT_BADADDR);
534 goto out;
535 }
536 }
537
538 switch (m->m_pkthdr.csum_flags &
539 ((ifp->if_csum_flags_rx & M_CSUM_IPv4) |
540 M_CSUM_IPv4_BAD)) {
541 case M_CSUM_IPv4|M_CSUM_IPv4_BAD:
542 INET_CSUM_COUNTER_INCR(&ip_hwcsum_bad);
543 IP_STATINC(IP_STAT_BADSUM);
544 goto out;
545
546 case M_CSUM_IPv4:
547 /* Checksum was okay. */
548 INET_CSUM_COUNTER_INCR(&ip_hwcsum_ok);
549 break;
550
551 default:
552 /*
553 * Must compute it ourselves. Maybe skip checksum on
554 * loopback interfaces.
555 */
556 if (__predict_true(!(ifp->if_flags & IFF_LOOPBACK) ||
557 ip_do_loopback_cksum)) {
558 INET_CSUM_COUNTER_INCR(&ip_swcsum);
559 if (in_cksum(m, hlen) != 0) {
560 IP_STATINC(IP_STAT_BADSUM);
561 goto out;
562 }
563 }
564 break;
565 }
566
567 /* Retrieve the packet length. */
568 len = ntohs(ip->ip_len);
569
570 /*
571 * Check for additional length bogosity
572 */
573 if (len < hlen) {
574 IP_STATINC(IP_STAT_BADLEN);
575 goto out;
576 }
577
578 /*
579 * Check that the amount of data in the buffers
580 * is as at least much as the IP header would have us expect.
581 * Trim mbufs if longer than we expect.
582 * Drop packet if shorter than we expect.
583 */
584 if (m->m_pkthdr.len < len) {
585 IP_STATINC(IP_STAT_TOOSHORT);
586 goto out;
587 }
588 if (m->m_pkthdr.len > len) {
589 if (m->m_len == m->m_pkthdr.len) {
590 m->m_len = len;
591 m->m_pkthdr.len = len;
592 } else
593 m_adj(m, len - m->m_pkthdr.len);
594 }
595
596 /*
597 * Assume that we can create a fast-forward IP flow entry
598 * based on this packet.
599 */
600 m->m_flags |= M_CANFASTFWD;
601
602 /*
603 * Run through list of hooks for input packets. If there are any
604 * filters which require that additional packets in the flow are
605 * not fast-forwarded, they must clear the M_CANFASTFWD flag.
606 * Note that filters must _never_ set this flag, as another filter
607 * in the list may have previously cleared it.
608 */
609 #if defined(IPSEC)
610 if (!ipsec_used || !ipsec_indone(m))
611 #else
612 if (1)
613 #endif
614 {
615 struct in_addr odst = ip->ip_dst;
616 bool freed;
617
618 freed = pfil_run_hooks(inet_pfil_hook, &m, ifp, PFIL_IN) != 0;
619 if (freed || m == NULL) {
620 m = NULL;
621 goto out;
622 }
623 ip = mtod(m, struct ip *);
624 hlen = ip->ip_hl << 2;
625
626 /*
627 * XXX The setting of "srcrt" here is to prevent ip_forward()
628 * from generating ICMP redirects for packets that have
629 * been redirected by a hook back out on to the same LAN that
630 * they came from and is not an indication that the packet
631 * is being inffluenced by source routing options. This
632 * allows things like
633 * "rdr tlp0 0/0 port 80 -> 1.1.1.200 3128 tcp"
634 * where tlp0 is both on the 1.1.1.0/24 network and is the
635 * default route for hosts on 1.1.1.0/24. Of course this
636 * also requires a "map tlp0 ..." to complete the story.
637 * One might argue whether or not this kind of network config.
638 * should be supported in this manner...
639 */
640 srcrt = (odst.s_addr != ip->ip_dst.s_addr);
641 }
642
643 #ifdef ALTQ
644 /* XXX Temporary until ALTQ is changed to use a pfil hook */
645 if (altq_input) {
646 SOFTNET_LOCK();
647 if ((*altq_input)(m, AF_INET) == 0) {
648 /* Packet dropped by traffic conditioner. */
649 SOFTNET_UNLOCK();
650 m = NULL;
651 goto out;
652 }
653 SOFTNET_UNLOCK();
654 }
655 #endif
656
657 /*
658 * Process options and, if not destined for us,
659 * ship it on. ip_dooptions returns 1 when an
660 * error was detected (causing an icmp message
661 * to be sent and the original packet to be freed).
662 */
663 if (hlen > sizeof (struct ip) && ip_dooptions(m)) {
664 m = NULL;
665 goto out;
666 }
667
668 /*
669 * Check our list of addresses, to see if the packet is for us.
670 *
671 * Traditional 4.4BSD did not consult IFF_UP at all.
672 * The behavior here is to treat addresses on !IFF_UP interface
673 * or IN_IFF_NOTREADY addresses as not mine.
674 */
675 downmatch = 0;
676 s = pserialize_read_enter();
677 ia = ip_match_our_address(ifp, ip, &downmatch);
678 if (ia != NULL) {
679 pserialize_read_exit(s);
680 goto ours;
681 }
682
683 if (ifp->if_flags & IFF_BROADCAST) {
684 ia = ip_match_our_address_broadcast(ifp, ip);
685 if (ia != NULL) {
686 pserialize_read_exit(s);
687 goto ours;
688 }
689 }
690 pserialize_read_exit(s);
691
692 if (IN_MULTICAST(ip->ip_dst.s_addr)) {
693 #ifdef MROUTING
694 extern struct socket *ip_mrouter;
695
696 if (ip_mrouter) {
697 /*
698 * If we are acting as a multicast router, all
699 * incoming multicast packets are passed to the
700 * kernel-level multicast forwarding function.
701 * The packet is returned (relatively) intact; if
702 * ip_mforward() returns a non-zero value, the packet
703 * must be discarded, else it may be accepted below.
704 *
705 * (The IP ident field is put in the same byte order
706 * as expected when ip_mforward() is called from
707 * ip_output().)
708 */
709 SOFTNET_LOCK();
710 if (ip_mforward(m, ifp) != 0) {
711 SOFTNET_UNLOCK();
712 IP_STATINC(IP_STAT_CANTFORWARD);
713 goto out;
714 }
715 SOFTNET_UNLOCK();
716
717 /*
718 * The process-level routing demon needs to receive
719 * all multicast IGMP packets, whether or not this
720 * host belongs to their destination groups.
721 */
722 if (ip->ip_p == IPPROTO_IGMP) {
723 goto ours;
724 }
725 IP_STATINC(IP_STAT_CANTFORWARD);
726 }
727 #endif
728 /*
729 * See if we belong to the destination multicast group on the
730 * arrival interface.
731 */
732 if (!in_multi_group(ip->ip_dst, ifp, 0)) {
733 IP_STATINC(IP_STAT_CANTFORWARD);
734 goto out;
735 }
736 goto ours;
737 }
738 if (ip->ip_dst.s_addr == INADDR_BROADCAST ||
739 in_nullhost(ip->ip_dst))
740 goto ours;
741
742 /*
743 * Not for us; forward if possible and desirable.
744 */
745 if (ipforwarding == 0) {
746 m_put_rcvif_psref(ifp, &psref);
747 IP_STATINC(IP_STAT_CANTFORWARD);
748 m_freem(m);
749 } else {
750 /*
751 * If ip_dst matched any of my address on !IFF_UP interface,
752 * and there's no IFF_UP interface that matches ip_dst,
753 * send icmp unreach. Forwarding it will result in in-kernel
754 * forwarding loop till TTL goes to 0.
755 */
756 if (downmatch) {
757 m_put_rcvif_psref(ifp, &psref);
758 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_HOST, 0, 0);
759 IP_STATINC(IP_STAT_CANTFORWARD);
760 return;
761 }
762 #ifdef IPSEC
763 /* Check the security policy (SP) for the packet */
764 if (ipsec_used) {
765 if (ipsec4_input(m, IP_FORWARDING |
766 (ip_directedbcast ? IP_ALLOWBROADCAST : 0)) != 0) {
767 goto out;
768 }
769 }
770 #endif
771 ip_forward(m, srcrt, ifp);
772 m_put_rcvif_psref(ifp, &psref);
773 }
774 return;
775
776 ours:
777 m_put_rcvif_psref(ifp, &psref);
778 ifp = NULL;
779
780 /*
781 * If offset or IP_MF are set, must reassemble.
782 */
783 if (ip->ip_off & ~htons(IP_DF|IP_RF)) {
784 /*
785 * Pass to IP reassembly mechanism.
786 */
787 if (ip_reass_packet(&m, ip) != 0) {
788 /* Failed; invalid fragment(s) or packet. */
789 goto out;
790 }
791 if (m == NULL) {
792 /* More fragments should come; silently return. */
793 goto out;
794 }
795 /*
796 * Reassembly is done, we have the final packet.
797 * Updated cached data in local variable(s).
798 */
799 ip = mtod(m, struct ip *);
800 hlen = ip->ip_hl << 2;
801 }
802
803 #ifdef IPSEC
804 /*
805 * Enforce IPsec policy checking if we are seeing last header.
806 * Note that we do not visit this with protocols with PCB layer
807 * code - like UDP/TCP/raw IP.
808 */
809 if (ipsec_used &&
810 (inetsw[ip_protox[ip->ip_p]].pr_flags & PR_LASTHDR) != 0) {
811 if (ipsec4_input(m, 0) != 0) {
812 goto out;
813 }
814 }
815 #endif
816
817 /*
818 * Switch out to protocol's input routine.
819 */
820 #if IFA_STATS
821 if (ia && ip) {
822 struct in_ifaddr *_ia;
823 /*
824 * Keep a reference from ip_match_our_address with psref
825 * is expensive, so explore ia here again.
826 */
827 s = pserialize_read_enter();
828 _ia = in_get_ia(ip->ip_dst);
829 _ia->ia_ifa.ifa_data.ifad_inbytes += ntohs(ip->ip_len);
830 pserialize_read_exit(s);
831 }
832 #endif
833 IP_STATINC(IP_STAT_DELIVERED);
834
835 const int off = hlen, nh = ip->ip_p;
836
837 (*inetsw[ip_protox[nh]].pr_input)(m, off, nh);
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 SOFTNET_KERNEL_LOCK_UNLESS_NET_MPSAFE();
854
855 ip_reass_slowtimo();
856
857 SOFTNET_KERNEL_UNLOCK_UNLESS_NET_MPSAFE();
858 }
859
860 /*
861 * IP drain processing.
862 */
863 void
864 ip_drain(void)
865 {
866
867 KERNEL_LOCK(1, NULL);
868 ip_reass_drain();
869 KERNEL_UNLOCK_ONE(NULL);
870 }
871
872 /*
873 * ip_dooptions: perform option processing on a datagram, possibly discarding
874 * it if bad options are encountered, or forwarding it if source-routed.
875 *
876 * => Returns true if packet has been forwarded/freed.
877 * => Returns false if the packet should be processed further.
878 */
879 static bool
880 ip_dooptions(struct mbuf *m)
881 {
882 struct ip *ip = mtod(m, struct ip *);
883 u_char *cp, *cp0;
884 struct ip_timestamp *ipt;
885 struct in_ifaddr *ia;
886 int opt, optlen, cnt, off, code, type = ICMP_PARAMPROB, forward = 0;
887 struct in_addr dst;
888 n_time ntime;
889 struct ifaddr *ifa = NULL;
890 int s;
891
892 dst = ip->ip_dst;
893 cp = (u_char *)(ip + 1);
894 cnt = (ip->ip_hl << 2) - sizeof (struct ip);
895 for (; cnt > 0; cnt -= optlen, cp += optlen) {
896 opt = cp[IPOPT_OPTVAL];
897 if (opt == IPOPT_EOL)
898 break;
899 if (opt == IPOPT_NOP)
900 optlen = 1;
901 else {
902 if (cnt < IPOPT_OLEN + sizeof(*cp)) {
903 code = &cp[IPOPT_OLEN] - (u_char *)ip;
904 goto bad;
905 }
906 optlen = cp[IPOPT_OLEN];
907 if (optlen < IPOPT_OLEN + sizeof(*cp) || optlen > cnt) {
908 code = &cp[IPOPT_OLEN] - (u_char *)ip;
909 goto bad;
910 }
911 }
912 switch (opt) {
913
914 default:
915 break;
916
917 /*
918 * Source routing with record.
919 * Find interface with current destination address.
920 * If none on this machine then drop if strictly routed,
921 * or do nothing if loosely routed.
922 * Record interface address and bring up next address
923 * component. If strictly routed make sure next
924 * address is on directly accessible net.
925 */
926 case IPOPT_LSRR:
927 case IPOPT_SSRR: {
928 struct psref psref;
929 struct sockaddr_in ipaddr = {
930 .sin_len = sizeof(ipaddr),
931 .sin_family = AF_INET,
932 };
933
934 if (ip_allowsrcrt == 0) {
935 type = ICMP_UNREACH;
936 code = ICMP_UNREACH_NET_PROHIB;
937 goto bad;
938 }
939 if (optlen < IPOPT_OFFSET + sizeof(*cp)) {
940 code = &cp[IPOPT_OLEN] - (u_char *)ip;
941 goto bad;
942 }
943 if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) {
944 code = &cp[IPOPT_OFFSET] - (u_char *)ip;
945 goto bad;
946 }
947 ipaddr.sin_addr = ip->ip_dst;
948
949 s = pserialize_read_enter();
950 ifa = ifa_ifwithaddr(sintosa(&ipaddr));
951 if (ifa == NULL) {
952 pserialize_read_exit(s);
953 if (opt == IPOPT_SSRR) {
954 type = ICMP_UNREACH;
955 code = ICMP_UNREACH_SRCFAIL;
956 goto bad;
957 }
958 /*
959 * Loose routing, and not at next destination
960 * yet; nothing to do except forward.
961 */
962 break;
963 }
964 pserialize_read_exit(s);
965
966 off--; /* 0 origin */
967 if ((off + sizeof(struct in_addr)) > optlen) {
968 /*
969 * End of source route. Should be for us.
970 */
971 save_rte(m, cp, ip->ip_src);
972 break;
973 }
974 /*
975 * locate outgoing interface
976 */
977 memcpy((void *)&ipaddr.sin_addr, (void *)(cp + off),
978 sizeof(ipaddr.sin_addr));
979 if (opt == IPOPT_SSRR) {
980 ifa = ifa_ifwithladdr_psref(sintosa(&ipaddr),
981 &psref);
982 if (ifa != NULL)
983 ia = ifatoia(ifa);
984 else
985 ia = NULL;
986 } else {
987 ia = ip_rtaddr(ipaddr.sin_addr, &psref);
988 }
989 if (ia == NULL) {
990 type = ICMP_UNREACH;
991 code = ICMP_UNREACH_SRCFAIL;
992 goto bad;
993 }
994 ip->ip_dst = ipaddr.sin_addr;
995 bcopy((void *)&ia->ia_addr.sin_addr,
996 (void *)(cp + off), sizeof(struct in_addr));
997 ia4_release(ia, &psref);
998 cp[IPOPT_OFFSET] += sizeof(struct in_addr);
999 /*
1000 * Let ip_intr's mcast routing check handle mcast pkts
1001 */
1002 forward = !IN_MULTICAST(ip->ip_dst.s_addr);
1003 break;
1004 }
1005
1006 case IPOPT_RR: {
1007 struct psref psref;
1008 struct sockaddr_in ipaddr = {
1009 .sin_len = sizeof(ipaddr),
1010 .sin_family = AF_INET,
1011 };
1012
1013 if (optlen < IPOPT_OFFSET + sizeof(*cp)) {
1014 code = &cp[IPOPT_OLEN] - (u_char *)ip;
1015 goto bad;
1016 }
1017 if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) {
1018 code = &cp[IPOPT_OFFSET] - (u_char *)ip;
1019 goto bad;
1020 }
1021 /*
1022 * If no space remains, ignore.
1023 */
1024 off--; /* 0 origin */
1025 if ((off + sizeof(struct in_addr)) > optlen)
1026 break;
1027 memcpy((void *)&ipaddr.sin_addr, (void *)(&ip->ip_dst),
1028 sizeof(ipaddr.sin_addr));
1029 /*
1030 * locate outgoing interface; if we're the destination,
1031 * use the incoming interface (should be same).
1032 */
1033 ifa = ifa_ifwithaddr_psref(sintosa(&ipaddr), &psref);
1034 if (ifa == NULL) {
1035 ia = ip_rtaddr(ipaddr.sin_addr, &psref);
1036 if (ia == NULL) {
1037 type = ICMP_UNREACH;
1038 code = ICMP_UNREACH_HOST;
1039 goto bad;
1040 }
1041 } else {
1042 ia = ifatoia(ifa);
1043 }
1044 bcopy((void *)&ia->ia_addr.sin_addr,
1045 (void *)(cp + off), sizeof(struct in_addr));
1046 ia4_release(ia, &psref);
1047 cp[IPOPT_OFFSET] += sizeof(struct in_addr);
1048 break;
1049 }
1050
1051 case IPOPT_TS:
1052 code = cp - (u_char *)ip;
1053 ipt = (struct ip_timestamp *)cp;
1054 if (ipt->ipt_len < 4 || ipt->ipt_len > 40) {
1055 code = (u_char *)&ipt->ipt_len - (u_char *)ip;
1056 goto bad;
1057 }
1058 if (ipt->ipt_ptr < 5) {
1059 code = (u_char *)&ipt->ipt_ptr - (u_char *)ip;
1060 goto bad;
1061 }
1062 if (ipt->ipt_ptr > ipt->ipt_len - sizeof (int32_t)) {
1063 if (++ipt->ipt_oflw == 0) {
1064 code = (u_char *)&ipt->ipt_ptr -
1065 (u_char *)ip;
1066 goto bad;
1067 }
1068 break;
1069 }
1070 cp0 = (cp + ipt->ipt_ptr - 1);
1071 switch (ipt->ipt_flg) {
1072
1073 case IPOPT_TS_TSONLY:
1074 break;
1075
1076 case IPOPT_TS_TSANDADDR: {
1077 struct ifnet *rcvif;
1078 int _s, _ss;
1079 struct sockaddr_in ipaddr = {
1080 .sin_len = sizeof(ipaddr),
1081 .sin_family = AF_INET,
1082 };
1083
1084 if (ipt->ipt_ptr - 1 + sizeof(n_time) +
1085 sizeof(struct in_addr) > ipt->ipt_len) {
1086 code = (u_char *)&ipt->ipt_ptr -
1087 (u_char *)ip;
1088 goto bad;
1089 }
1090 ipaddr.sin_addr = dst;
1091 _ss = pserialize_read_enter();
1092 rcvif = m_get_rcvif(m, &_s);
1093 if (__predict_true(rcvif != NULL)) {
1094 ifa = ifaof_ifpforaddr(sintosa(&ipaddr),
1095 rcvif);
1096 }
1097 m_put_rcvif(rcvif, &_s);
1098 if (ifa == NULL) {
1099 pserialize_read_exit(_ss);
1100 break;
1101 }
1102 ia = ifatoia(ifa);
1103 bcopy(&ia->ia_addr.sin_addr,
1104 cp0, sizeof(struct in_addr));
1105 pserialize_read_exit(_ss);
1106 ipt->ipt_ptr += sizeof(struct in_addr);
1107 break;
1108 }
1109
1110 case IPOPT_TS_PRESPEC: {
1111 struct sockaddr_in ipaddr = {
1112 .sin_len = sizeof(ipaddr),
1113 .sin_family = AF_INET,
1114 };
1115
1116 if (ipt->ipt_ptr - 1 + sizeof(n_time) +
1117 sizeof(struct in_addr) > ipt->ipt_len) {
1118 code = (u_char *)&ipt->ipt_ptr -
1119 (u_char *)ip;
1120 goto bad;
1121 }
1122 memcpy(&ipaddr.sin_addr, cp0,
1123 sizeof(struct in_addr));
1124 s = pserialize_read_enter();
1125 ifa = ifa_ifwithaddr(sintosa(&ipaddr));
1126 if (ifa == NULL) {
1127 pserialize_read_exit(s);
1128 continue;
1129 }
1130 pserialize_read_exit(s);
1131 ipt->ipt_ptr += sizeof(struct in_addr);
1132 break;
1133 }
1134
1135 default:
1136 /* XXX can't take &ipt->ipt_flg */
1137 code = (u_char *)&ipt->ipt_ptr -
1138 (u_char *)ip + 1;
1139 goto bad;
1140 }
1141 ntime = iptime();
1142 cp0 = (u_char *) &ntime; /* XXX grumble, GCC... */
1143 memmove((char *)cp + ipt->ipt_ptr - 1, cp0,
1144 sizeof(n_time));
1145 ipt->ipt_ptr += sizeof(n_time);
1146 }
1147 }
1148 if (forward) {
1149 struct ifnet *rcvif;
1150 struct psref _psref;
1151
1152 if (ip_forwsrcrt == 0) {
1153 type = ICMP_UNREACH;
1154 code = ICMP_UNREACH_SRCFAIL;
1155 goto bad;
1156 }
1157
1158 rcvif = m_get_rcvif_psref(m, &_psref);
1159 if (__predict_false(rcvif == NULL)) {
1160 type = ICMP_UNREACH;
1161 code = ICMP_UNREACH_HOST;
1162 goto bad;
1163 }
1164 ip_forward(m, 1, rcvif);
1165 m_put_rcvif_psref(rcvif, &_psref);
1166 return true;
1167 }
1168 return false;
1169 bad:
1170 icmp_error(m, type, code, 0, 0);
1171 IP_STATINC(IP_STAT_BADOPTIONS);
1172 return true;
1173 }
1174
1175 /*
1176 * ip_rtaddr: given address of next destination (final or next hop),
1177 * return internet address info of interface to be used to get there.
1178 */
1179 static struct in_ifaddr *
1180 ip_rtaddr(struct in_addr dst, struct psref *psref)
1181 {
1182 struct rtentry *rt;
1183 union {
1184 struct sockaddr dst;
1185 struct sockaddr_in dst4;
1186 } u;
1187 struct route *ro;
1188
1189 sockaddr_in_init(&u.dst4, &dst, 0);
1190
1191 ro = percpu_getref(ipforward_rt_percpu);
1192 rt = rtcache_lookup(ro, &u.dst);
1193 if (rt == NULL) {
1194 percpu_putref(ipforward_rt_percpu);
1195 return NULL;
1196 }
1197
1198 ia4_acquire(ifatoia(rt->rt_ifa), psref);
1199 rtcache_unref(rt, ro);
1200 percpu_putref(ipforward_rt_percpu);
1201
1202 return ifatoia(rt->rt_ifa);
1203 }
1204
1205 /*
1206 * save_rte: save incoming source route for use in replies, to be picked
1207 * up later by ip_srcroute if the receiver is interested.
1208 */
1209 static void
1210 save_rte(struct mbuf *m, u_char *option, struct in_addr dst)
1211 {
1212 struct ip_srcrt *isr;
1213 struct m_tag *mtag;
1214 unsigned olen;
1215
1216 olen = option[IPOPT_OLEN];
1217 if (olen > sizeof(isr->isr_hdr) + sizeof(isr->isr_routes))
1218 return;
1219
1220 mtag = m_tag_get(PACKET_TAG_SRCROUTE, sizeof(*isr), M_NOWAIT);
1221 if (mtag == NULL)
1222 return;
1223 isr = (struct ip_srcrt *)(mtag + 1);
1224
1225 memcpy(isr->isr_hdr, option, olen);
1226 isr->isr_nhops = (olen - IPOPT_OFFSET - 1) / sizeof(struct in_addr);
1227 isr->isr_dst = dst;
1228 m_tag_prepend(m, mtag);
1229 }
1230
1231 /*
1232 * Retrieve incoming source route for use in replies,
1233 * in the same form used by setsockopt.
1234 * The first hop is placed before the options, will be removed later.
1235 */
1236 struct mbuf *
1237 ip_srcroute(struct mbuf *m0)
1238 {
1239 struct in_addr *p, *q;
1240 struct mbuf *m;
1241 struct ip_srcrt *isr;
1242 struct m_tag *mtag;
1243
1244 mtag = m_tag_find(m0, PACKET_TAG_SRCROUTE, NULL);
1245 if (mtag == NULL)
1246 return NULL;
1247 isr = (struct ip_srcrt *)(mtag + 1);
1248
1249 if (isr->isr_nhops == 0)
1250 return NULL;
1251
1252 m = m_get(M_DONTWAIT, MT_SOOPTS);
1253 if (m == NULL)
1254 return NULL;
1255
1256 MCLAIM(m, &inetdomain.dom_mowner);
1257 #define OPTSIZ (sizeof(isr->isr_nop) + sizeof(isr->isr_hdr))
1258
1259 /* length is (nhops+1)*sizeof(addr) + sizeof(nop + header) */
1260 m->m_len = (isr->isr_nhops + 1) * sizeof(struct in_addr) + OPTSIZ;
1261
1262 /*
1263 * First save first hop for return route
1264 */
1265 p = &(isr->isr_routes[isr->isr_nhops - 1]);
1266 *(mtod(m, struct in_addr *)) = *p--;
1267
1268 /*
1269 * Copy option fields and padding (nop) to mbuf.
1270 */
1271 isr->isr_nop = IPOPT_NOP;
1272 isr->isr_hdr[IPOPT_OFFSET] = IPOPT_MINOFF;
1273 memmove(mtod(m, char *) + sizeof(struct in_addr), &isr->isr_nop,
1274 OPTSIZ);
1275 q = (struct in_addr *)(mtod(m, char *) +
1276 sizeof(struct in_addr) + OPTSIZ);
1277 #undef OPTSIZ
1278 /*
1279 * Record return path as an IP source route,
1280 * reversing the path (pointers are now aligned).
1281 */
1282 while (p >= isr->isr_routes) {
1283 *q++ = *p--;
1284 }
1285 /*
1286 * Last hop goes to final destination.
1287 */
1288 *q = isr->isr_dst;
1289 m_tag_delete(m0, mtag);
1290 return m;
1291 }
1292
1293 const int inetctlerrmap[PRC_NCMDS] = {
1294 [PRC_MSGSIZE] = EMSGSIZE,
1295 [PRC_HOSTDEAD] = EHOSTDOWN,
1296 [PRC_HOSTUNREACH] = EHOSTUNREACH,
1297 [PRC_UNREACH_NET] = EHOSTUNREACH,
1298 [PRC_UNREACH_HOST] = EHOSTUNREACH,
1299 [PRC_UNREACH_PROTOCOL] = ECONNREFUSED,
1300 [PRC_UNREACH_PORT] = ECONNREFUSED,
1301 [PRC_UNREACH_SRCFAIL] = EHOSTUNREACH,
1302 [PRC_PARAMPROB] = ENOPROTOOPT,
1303 };
1304
1305 void
1306 ip_fasttimo(void)
1307 {
1308 if (ip_drainwanted) {
1309 ip_drain();
1310 ip_drainwanted = 0;
1311 }
1312 }
1313
1314 void
1315 ip_drainstub(void)
1316 {
1317 ip_drainwanted = 1;
1318 }
1319
1320 /*
1321 * Forward a packet. If some error occurs return the sender
1322 * an icmp packet. Note we can't always generate a meaningful
1323 * icmp message because icmp doesn't have a large enough repertoire
1324 * of codes and types.
1325 *
1326 * If not forwarding, just drop the packet. This could be confusing
1327 * if ipforwarding was zero but some routing protocol was advancing
1328 * us as a gateway to somewhere. However, we must let the routing
1329 * protocol deal with that.
1330 *
1331 * The srcrt parameter indicates whether the packet is being forwarded
1332 * via a source route.
1333 */
1334 static void
1335 ip_forward(struct mbuf *m, int srcrt, struct ifnet *rcvif)
1336 {
1337 struct ip *ip = mtod(m, struct ip *);
1338 struct rtentry *rt;
1339 int error, type = 0, code = 0, destmtu = 0;
1340 struct mbuf *mcopy;
1341 n_long dest;
1342 union {
1343 struct sockaddr dst;
1344 struct sockaddr_in dst4;
1345 } u;
1346 uint64_t *ips;
1347 struct route *ro;
1348
1349 KASSERTMSG(cpu_softintr_p(), "ip_forward: not in the software "
1350 "interrupt handler; synchronization assumptions violated");
1351
1352 /*
1353 * We are now in the output path.
1354 */
1355 MCLAIM(m, &ip_tx_mowner);
1356
1357 /*
1358 * Clear any in-bound checksum flags for this packet.
1359 */
1360 m->m_pkthdr.csum_flags = 0;
1361
1362 dest = 0;
1363 if (m->m_flags & (M_BCAST|M_MCAST) || in_canforward(ip->ip_dst) == 0) {
1364 IP_STATINC(IP_STAT_CANTFORWARD);
1365 m_freem(m);
1366 return;
1367 }
1368
1369 if (ip->ip_ttl <= IPTTLDEC) {
1370 icmp_error(m, ICMP_TIMXCEED, ICMP_TIMXCEED_INTRANS, dest, 0);
1371 return;
1372 }
1373
1374 sockaddr_in_init(&u.dst4, &ip->ip_dst, 0);
1375
1376 ro = percpu_getref(ipforward_rt_percpu);
1377 rt = rtcache_lookup(ro, &u.dst);
1378 if (rt == NULL) {
1379 percpu_putref(ipforward_rt_percpu);
1380 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_NET, dest, 0);
1381 return;
1382 }
1383
1384 /*
1385 * Save at most 68 bytes of the packet in case
1386 * we need to generate an ICMP message to the src.
1387 * Pullup to avoid sharing mbuf cluster between m and mcopy.
1388 */
1389 mcopy = m_copym(m, 0, imin(ntohs(ip->ip_len), 68), M_DONTWAIT);
1390 if (mcopy)
1391 mcopy = m_pullup(mcopy, ip->ip_hl << 2);
1392
1393 ip->ip_ttl -= IPTTLDEC;
1394
1395 /*
1396 * If forwarding packet using same interface that it came in on,
1397 * perhaps should send a redirect to sender to shortcut a hop.
1398 * Only send redirect if source is sending directly to us,
1399 * and if packet was not source routed (or has any options).
1400 * Also, don't send redirect if forwarding using a default route
1401 * or a route modified by a redirect.
1402 */
1403 if (rt->rt_ifp == rcvif &&
1404 (rt->rt_flags & (RTF_DYNAMIC|RTF_MODIFIED)) == 0 &&
1405 !in_nullhost(satocsin(rt_getkey(rt))->sin_addr) &&
1406 ipsendredirects && !srcrt) {
1407 if (rt->rt_ifa &&
1408 (ip->ip_src.s_addr & ifatoia(rt->rt_ifa)->ia_subnetmask) ==
1409 ifatoia(rt->rt_ifa)->ia_subnet) {
1410 if (rt->rt_flags & RTF_GATEWAY)
1411 dest = satosin(rt->rt_gateway)->sin_addr.s_addr;
1412 else
1413 dest = ip->ip_dst.s_addr;
1414 /*
1415 * Router requirements says to only send host
1416 * redirects.
1417 */
1418 type = ICMP_REDIRECT;
1419 code = ICMP_REDIRECT_HOST;
1420 }
1421 }
1422 rtcache_unref(rt, ro);
1423
1424 error = ip_output(m, NULL, ro,
1425 (IP_FORWARDING | (ip_directedbcast ? IP_ALLOWBROADCAST : 0)),
1426 NULL, NULL);
1427
1428 if (error) {
1429 IP_STATINC(IP_STAT_CANTFORWARD);
1430 goto error;
1431 }
1432
1433 ips = IP_STAT_GETREF();
1434 ips[IP_STAT_FORWARD]++;
1435
1436 if (type) {
1437 ips[IP_STAT_REDIRECTSENT]++;
1438 IP_STAT_PUTREF();
1439 goto redirect;
1440 }
1441
1442 IP_STAT_PUTREF();
1443 if (mcopy) {
1444 #ifdef GATEWAY
1445 if (mcopy->m_flags & M_CANFASTFWD)
1446 ipflow_create(ro, mcopy);
1447 #endif
1448 m_freem(mcopy);
1449 }
1450
1451 percpu_putref(ipforward_rt_percpu);
1452 return;
1453
1454 redirect:
1455 error:
1456 if (mcopy == NULL) {
1457 percpu_putref(ipforward_rt_percpu);
1458 return;
1459 }
1460
1461 switch (error) {
1462
1463 case 0: /* forwarded, but need redirect */
1464 /* type, code set above */
1465 break;
1466
1467 case ENETUNREACH: /* shouldn't happen, checked above */
1468 case EHOSTUNREACH:
1469 case ENETDOWN:
1470 case EHOSTDOWN:
1471 default:
1472 type = ICMP_UNREACH;
1473 code = ICMP_UNREACH_HOST;
1474 break;
1475
1476 case EMSGSIZE:
1477 type = ICMP_UNREACH;
1478 code = ICMP_UNREACH_NEEDFRAG;
1479
1480 if ((rt = rtcache_validate(ro)) != NULL) {
1481 destmtu = rt->rt_ifp->if_mtu;
1482 rtcache_unref(rt, ro);
1483 }
1484 #ifdef IPSEC
1485 if (ipsec_used)
1486 (void)ipsec4_forward(mcopy, &destmtu);
1487 #endif
1488 IP_STATINC(IP_STAT_CANTFRAG);
1489 break;
1490
1491 case ENOBUFS:
1492 /*
1493 * Do not generate ICMP_SOURCEQUENCH as required in RFC 1812,
1494 * Requirements for IP Version 4 Routers. Source quench can
1495 * big problem under DoS attacks or if the underlying
1496 * interface is rate-limited.
1497 */
1498 if (mcopy)
1499 m_freem(mcopy);
1500 percpu_putref(ipforward_rt_percpu);
1501 return;
1502 }
1503 icmp_error(mcopy, type, code, dest, destmtu);
1504 percpu_putref(ipforward_rt_percpu);
1505 }
1506
1507 void
1508 ip_savecontrol(struct inpcb *inp, struct mbuf **mp, struct ip *ip,
1509 struct mbuf *m)
1510 {
1511 struct socket *so = inp->inp_socket;
1512 ifnet_t *ifp;
1513 int inpflags = inp->inp_flags;
1514 struct psref psref;
1515
1516 ifp = m_get_rcvif_psref(m, &psref);
1517 if (__predict_false(ifp == NULL))
1518 return; /* XXX should report error? */
1519
1520 if (so->so_options & SO_TIMESTAMP
1521 #ifdef SO_OTIMESTAMP
1522 || so->so_options & SO_OTIMESTAMP
1523 #endif
1524 ) {
1525 struct timeval tv;
1526
1527 microtime(&tv);
1528 #ifdef SO_OTIMESTAMP
1529 if (so->so_options & SO_OTIMESTAMP) {
1530 struct timeval50 tv50;
1531 timeval_to_timeval50(&tv, &tv50);
1532 *mp = sbcreatecontrol((void *) &tv50, sizeof(tv50),
1533 SCM_OTIMESTAMP, SOL_SOCKET);
1534 } else
1535 #endif
1536 *mp = sbcreatecontrol((void *) &tv, sizeof(tv),
1537 SCM_TIMESTAMP, SOL_SOCKET);
1538 if (*mp)
1539 mp = &(*mp)->m_next;
1540 }
1541 if (inpflags & INP_RECVDSTADDR) {
1542 *mp = sbcreatecontrol((void *) &ip->ip_dst,
1543 sizeof(struct in_addr), IP_RECVDSTADDR, IPPROTO_IP);
1544 if (*mp)
1545 mp = &(*mp)->m_next;
1546 }
1547 if (inpflags & INP_RECVPKTINFO) {
1548 struct in_pktinfo ipi;
1549 ipi.ipi_addr = ip->ip_src;
1550 ipi.ipi_ifindex = ifp->if_index;
1551 *mp = sbcreatecontrol((void *) &ipi,
1552 sizeof(ipi), IP_RECVPKTINFO, IPPROTO_IP);
1553 if (*mp)
1554 mp = &(*mp)->m_next;
1555 }
1556 if (inpflags & INP_PKTINFO) {
1557 struct in_pktinfo ipi;
1558 ipi.ipi_addr = ip->ip_dst;
1559 ipi.ipi_ifindex = ifp->if_index;
1560 *mp = sbcreatecontrol((void *) &ipi,
1561 sizeof(ipi), IP_PKTINFO, IPPROTO_IP);
1562 if (*mp)
1563 mp = &(*mp)->m_next;
1564 }
1565 if (inpflags & INP_RECVIF) {
1566 struct sockaddr_dl sdl;
1567
1568 sockaddr_dl_init(&sdl, sizeof(sdl), ifp->if_index, 0, NULL, 0,
1569 NULL, 0);
1570 *mp = sbcreatecontrol(&sdl, sdl.sdl_len, IP_RECVIF, IPPROTO_IP);
1571 if (*mp)
1572 mp = &(*mp)->m_next;
1573 }
1574 if (inpflags & INP_RECVTTL) {
1575 *mp = sbcreatecontrol((void *) &ip->ip_ttl,
1576 sizeof(uint8_t), IP_RECVTTL, IPPROTO_IP);
1577 if (*mp)
1578 mp = &(*mp)->m_next;
1579 }
1580 m_put_rcvif_psref(ifp, &psref);
1581 }
1582
1583 /*
1584 * sysctl helper routine for net.inet.ip.forwsrcrt.
1585 */
1586 static int
1587 sysctl_net_inet_ip_forwsrcrt(SYSCTLFN_ARGS)
1588 {
1589 int error, tmp;
1590 struct sysctlnode node;
1591
1592 node = *rnode;
1593 tmp = ip_forwsrcrt;
1594 node.sysctl_data = &tmp;
1595 error = sysctl_lookup(SYSCTLFN_CALL(&node));
1596 if (error || newp == NULL)
1597 return (error);
1598
1599 error = kauth_authorize_network(l->l_cred, KAUTH_NETWORK_FORWSRCRT,
1600 0, NULL, NULL, NULL);
1601 if (error)
1602 return (error);
1603
1604 ip_forwsrcrt = tmp;
1605
1606 return (0);
1607 }
1608
1609 /*
1610 * sysctl helper routine for net.inet.ip.mtudisctimeout. checks the
1611 * range of the new value and tweaks timers if it changes.
1612 */
1613 static int
1614 sysctl_net_inet_ip_pmtudto(SYSCTLFN_ARGS)
1615 {
1616 int error, tmp;
1617 struct sysctlnode node;
1618
1619 icmp_mtudisc_lock();
1620
1621 node = *rnode;
1622 tmp = ip_mtudisc_timeout;
1623 node.sysctl_data = &tmp;
1624 error = sysctl_lookup(SYSCTLFN_CALL(&node));
1625 if (error || newp == NULL)
1626 goto out;
1627 if (tmp < 0) {
1628 error = EINVAL;
1629 goto out;
1630 }
1631
1632 ip_mtudisc_timeout = tmp;
1633 rt_timer_queue_change(ip_mtudisc_timeout_q, ip_mtudisc_timeout);
1634 error = 0;
1635 out:
1636 icmp_mtudisc_unlock();
1637 return error;
1638 }
1639
1640 static int
1641 sysctl_net_inet_ip_stats(SYSCTLFN_ARGS)
1642 {
1643
1644 return (NETSTAT_SYSCTL(ipstat_percpu, IP_NSTATS));
1645 }
1646
1647 static void
1648 sysctl_net_inet_ip_setup(struct sysctllog **clog)
1649 {
1650 sysctl_createv(clog, 0, NULL, NULL,
1651 CTLFLAG_PERMANENT,
1652 CTLTYPE_NODE, "inet",
1653 SYSCTL_DESCR("PF_INET related settings"),
1654 NULL, 0, NULL, 0,
1655 CTL_NET, PF_INET, CTL_EOL);
1656 sysctl_createv(clog, 0, NULL, NULL,
1657 CTLFLAG_PERMANENT,
1658 CTLTYPE_NODE, "ip",
1659 SYSCTL_DESCR("IPv4 related settings"),
1660 NULL, 0, NULL, 0,
1661 CTL_NET, PF_INET, IPPROTO_IP, CTL_EOL);
1662
1663 sysctl_createv(clog, 0, NULL, NULL,
1664 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1665 CTLTYPE_INT, "forwarding",
1666 SYSCTL_DESCR("Enable forwarding of INET datagrams"),
1667 NULL, 0, &ipforwarding, 0,
1668 CTL_NET, PF_INET, IPPROTO_IP,
1669 IPCTL_FORWARDING, CTL_EOL);
1670 sysctl_createv(clog, 0, NULL, NULL,
1671 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1672 CTLTYPE_INT, "redirect",
1673 SYSCTL_DESCR("Enable sending of ICMP redirect messages"),
1674 NULL, 0, &ipsendredirects, 0,
1675 CTL_NET, PF_INET, IPPROTO_IP,
1676 IPCTL_SENDREDIRECTS, CTL_EOL);
1677 sysctl_createv(clog, 0, NULL, NULL,
1678 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1679 CTLTYPE_INT, "ttl",
1680 SYSCTL_DESCR("Default TTL for an INET datagram"),
1681 NULL, 0, &ip_defttl, 0,
1682 CTL_NET, PF_INET, IPPROTO_IP,
1683 IPCTL_DEFTTL, CTL_EOL);
1684 #ifdef IPCTL_DEFMTU
1685 sysctl_createv(clog, 0, NULL, NULL,
1686 CTLFLAG_PERMANENT /* |CTLFLAG_READWRITE? */,
1687 CTLTYPE_INT, "mtu",
1688 SYSCTL_DESCR("Default MTA for an INET route"),
1689 NULL, 0, &ip_mtu, 0,
1690 CTL_NET, PF_INET, IPPROTO_IP,
1691 IPCTL_DEFMTU, CTL_EOL);
1692 #endif /* IPCTL_DEFMTU */
1693 sysctl_createv(clog, 0, NULL, NULL,
1694 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1695 CTLTYPE_INT, "forwsrcrt",
1696 SYSCTL_DESCR("Enable forwarding of source-routed "
1697 "datagrams"),
1698 sysctl_net_inet_ip_forwsrcrt, 0, &ip_forwsrcrt, 0,
1699 CTL_NET, PF_INET, IPPROTO_IP,
1700 IPCTL_FORWSRCRT, CTL_EOL);
1701 sysctl_createv(clog, 0, NULL, NULL,
1702 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1703 CTLTYPE_INT, "directed-broadcast",
1704 SYSCTL_DESCR("Enable forwarding of broadcast datagrams"),
1705 NULL, 0, &ip_directedbcast, 0,
1706 CTL_NET, PF_INET, IPPROTO_IP,
1707 IPCTL_DIRECTEDBCAST, CTL_EOL);
1708 sysctl_createv(clog, 0, NULL, NULL,
1709 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1710 CTLTYPE_INT, "allowsrcrt",
1711 SYSCTL_DESCR("Accept source-routed datagrams"),
1712 NULL, 0, &ip_allowsrcrt, 0,
1713 CTL_NET, PF_INET, IPPROTO_IP,
1714 IPCTL_ALLOWSRCRT, CTL_EOL);
1715
1716 sysctl_createv(clog, 0, NULL, NULL,
1717 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1718 CTLTYPE_INT, "mtudisc",
1719 SYSCTL_DESCR("Use RFC1191 Path MTU Discovery"),
1720 NULL, 0, &ip_mtudisc, 0,
1721 CTL_NET, PF_INET, IPPROTO_IP,
1722 IPCTL_MTUDISC, CTL_EOL);
1723 sysctl_createv(clog, 0, NULL, NULL,
1724 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1725 CTLTYPE_INT, "anonportmin",
1726 SYSCTL_DESCR("Lowest ephemeral port number to assign"),
1727 sysctl_net_inet_ip_ports, 0, &anonportmin, 0,
1728 CTL_NET, PF_INET, IPPROTO_IP,
1729 IPCTL_ANONPORTMIN, CTL_EOL);
1730 sysctl_createv(clog, 0, NULL, NULL,
1731 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1732 CTLTYPE_INT, "anonportmax",
1733 SYSCTL_DESCR("Highest ephemeral port number to assign"),
1734 sysctl_net_inet_ip_ports, 0, &anonportmax, 0,
1735 CTL_NET, PF_INET, IPPROTO_IP,
1736 IPCTL_ANONPORTMAX, CTL_EOL);
1737 sysctl_createv(clog, 0, NULL, NULL,
1738 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1739 CTLTYPE_INT, "mtudisctimeout",
1740 SYSCTL_DESCR("Lifetime of a Path MTU Discovered route"),
1741 sysctl_net_inet_ip_pmtudto, 0, (void *)&ip_mtudisc_timeout, 0,
1742 CTL_NET, PF_INET, IPPROTO_IP,
1743 IPCTL_MTUDISCTIMEOUT, CTL_EOL);
1744 #ifndef IPNOPRIVPORTS
1745 sysctl_createv(clog, 0, NULL, NULL,
1746 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1747 CTLTYPE_INT, "lowportmin",
1748 SYSCTL_DESCR("Lowest privileged ephemeral port number "
1749 "to assign"),
1750 sysctl_net_inet_ip_ports, 0, &lowportmin, 0,
1751 CTL_NET, PF_INET, IPPROTO_IP,
1752 IPCTL_LOWPORTMIN, CTL_EOL);
1753 sysctl_createv(clog, 0, NULL, NULL,
1754 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1755 CTLTYPE_INT, "lowportmax",
1756 SYSCTL_DESCR("Highest privileged ephemeral port number "
1757 "to assign"),
1758 sysctl_net_inet_ip_ports, 0, &lowportmax, 0,
1759 CTL_NET, PF_INET, IPPROTO_IP,
1760 IPCTL_LOWPORTMAX, CTL_EOL);
1761 #endif /* IPNOPRIVPORTS */
1762 #if NGRE > 0
1763 sysctl_createv(clog, 0, NULL, NULL,
1764 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1765 CTLTYPE_INT, "grettl",
1766 SYSCTL_DESCR("Default TTL for a gre tunnel datagram"),
1767 NULL, 0, &ip_gre_ttl, 0,
1768 CTL_NET, PF_INET, IPPROTO_IP,
1769 IPCTL_GRE_TTL, CTL_EOL);
1770 #endif /* NGRE */
1771 sysctl_createv(clog, 0, NULL, NULL,
1772 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1773 CTLTYPE_INT, "checkinterface",
1774 SYSCTL_DESCR("Enable receive side of Strong ES model "
1775 "from RFC1122"),
1776 NULL, 0, &ip_checkinterface, 0,
1777 CTL_NET, PF_INET, IPPROTO_IP,
1778 IPCTL_CHECKINTERFACE, CTL_EOL);
1779 sysctl_createv(clog, 0, NULL, NULL,
1780 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1781 CTLTYPE_INT, "random_id",
1782 SYSCTL_DESCR("Assign random ip_id values"),
1783 NULL, 0, &ip_do_randomid, 0,
1784 CTL_NET, PF_INET, IPPROTO_IP,
1785 IPCTL_RANDOMID, CTL_EOL);
1786 sysctl_createv(clog, 0, NULL, NULL,
1787 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1788 CTLTYPE_INT, "do_loopback_cksum",
1789 SYSCTL_DESCR("Perform IP checksum on loopback"),
1790 NULL, 0, &ip_do_loopback_cksum, 0,
1791 CTL_NET, PF_INET, IPPROTO_IP,
1792 IPCTL_LOOPBACKCKSUM, CTL_EOL);
1793 sysctl_createv(clog, 0, NULL, NULL,
1794 CTLFLAG_PERMANENT,
1795 CTLTYPE_STRUCT, "stats",
1796 SYSCTL_DESCR("IP statistics"),
1797 sysctl_net_inet_ip_stats, 0, NULL, 0,
1798 CTL_NET, PF_INET, IPPROTO_IP, IPCTL_STATS,
1799 CTL_EOL);
1800 #if NARP
1801 sysctl_createv(clog, 0, NULL, NULL,
1802 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1803 CTLTYPE_INT, "dad_count",
1804 SYSCTL_DESCR("Number of Duplicate Address Detection "
1805 "probes to send"),
1806 NULL, 0, &ip_dad_count, 0,
1807 CTL_NET, PF_INET, IPPROTO_IP,
1808 IPCTL_DAD_COUNT, CTL_EOL);
1809 #endif
1810
1811 /* anonportalgo RFC6056 subtree */
1812 const struct sysctlnode *portalgo_node;
1813 sysctl_createv(clog, 0, NULL, &portalgo_node,
1814 CTLFLAG_PERMANENT,
1815 CTLTYPE_NODE, "anonportalgo",
1816 SYSCTL_DESCR("Anonymous Port Algorithm Selection (RFC 6056)"),
1817 NULL, 0, NULL, 0,
1818 CTL_NET, PF_INET, IPPROTO_IP, CTL_CREATE, CTL_EOL);
1819 sysctl_createv(clog, 0, &portalgo_node, NULL,
1820 CTLFLAG_PERMANENT,
1821 CTLTYPE_STRING, "available",
1822 SYSCTL_DESCR("available algorithms"),
1823 sysctl_portalgo_available, 0, NULL, PORTALGO_MAXLEN,
1824 CTL_CREATE, CTL_EOL);
1825 sysctl_createv(clog, 0, &portalgo_node, NULL,
1826 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1827 CTLTYPE_STRING, "selected",
1828 SYSCTL_DESCR("selected algorithm"),
1829 sysctl_portalgo_selected4, 0, NULL, PORTALGO_MAXLEN,
1830 CTL_CREATE, CTL_EOL);
1831 sysctl_createv(clog, 0, &portalgo_node, NULL,
1832 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1833 CTLTYPE_STRUCT, "reserve",
1834 SYSCTL_DESCR("bitmap of reserved ports"),
1835 sysctl_portalgo_reserve4, 0, NULL, 0,
1836 CTL_CREATE, CTL_EOL);
1837 }
1838
1839 void
1840 ip_statinc(u_int stat)
1841 {
1842
1843 KASSERT(stat < IP_NSTATS);
1844 IP_STATINC(stat);
1845 }
1846