ip_icmp.c revision 1.116 1 1.116 thorpej /* $NetBSD: ip_icmp.c,v 1.116 2008/04/12 05:58:22 thorpej Exp $ */
2 1.37 itojun
3 1.37 itojun /*
4 1.37 itojun * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
5 1.37 itojun * All rights reserved.
6 1.67 itojun *
7 1.37 itojun * Redistribution and use in source and binary forms, with or without
8 1.37 itojun * modification, are permitted provided that the following conditions
9 1.37 itojun * are met:
10 1.37 itojun * 1. Redistributions of source code must retain the above copyright
11 1.37 itojun * notice, this list of conditions and the following disclaimer.
12 1.37 itojun * 2. Redistributions in binary form must reproduce the above copyright
13 1.37 itojun * notice, this list of conditions and the following disclaimer in the
14 1.37 itojun * documentation and/or other materials provided with the distribution.
15 1.37 itojun * 3. Neither the name of the project nor the names of its contributors
16 1.37 itojun * may be used to endorse or promote products derived from this software
17 1.37 itojun * without specific prior written permission.
18 1.67 itojun *
19 1.37 itojun * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
20 1.37 itojun * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 1.37 itojun * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 1.37 itojun * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
23 1.37 itojun * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 1.37 itojun * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 1.37 itojun * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 1.37 itojun * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 1.37 itojun * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 1.37 itojun * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 1.37 itojun * SUCH DAMAGE.
30 1.37 itojun */
31 1.10 cgd
32 1.31 thorpej /*-
33 1.55 thorpej * Copyright (c) 1998, 2000 The NetBSD Foundation, Inc.
34 1.31 thorpej * All rights reserved.
35 1.31 thorpej *
36 1.31 thorpej * This code is derived from software contributed to The NetBSD Foundation
37 1.31 thorpej * by Public Access Networks Corporation ("Panix"). It was developed under
38 1.31 thorpej * contract to Panix by Eric Haszlakiewicz and Thor Lancelot Simon.
39 1.31 thorpej *
40 1.55 thorpej * This code is derived from software contributed to The NetBSD Foundation
41 1.55 thorpej * by Jason R. Thorpe of Zembu Labs, Inc.
42 1.55 thorpej *
43 1.31 thorpej * Redistribution and use in source and binary forms, with or without
44 1.31 thorpej * modification, are permitted provided that the following conditions
45 1.31 thorpej * are met:
46 1.31 thorpej * 1. Redistributions of source code must retain the above copyright
47 1.31 thorpej * notice, this list of conditions and the following disclaimer.
48 1.31 thorpej * 2. Redistributions in binary form must reproduce the above copyright
49 1.31 thorpej * notice, this list of conditions and the following disclaimer in the
50 1.31 thorpej * documentation and/or other materials provided with the distribution.
51 1.31 thorpej * 3. All advertising materials mentioning features or use of this software
52 1.31 thorpej * must display the following acknowledgement:
53 1.31 thorpej * This product includes software developed by the NetBSD
54 1.31 thorpej * Foundation, Inc. and its contributors.
55 1.31 thorpej * 4. Neither the name of The NetBSD Foundation nor the names of its
56 1.31 thorpej * contributors may be used to endorse or promote products derived
57 1.31 thorpej * from this software without specific prior written permission.
58 1.31 thorpej *
59 1.31 thorpej * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
60 1.31 thorpej * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
61 1.31 thorpej * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
62 1.31 thorpej * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
63 1.31 thorpej * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
64 1.31 thorpej * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
65 1.31 thorpej * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
66 1.31 thorpej * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
67 1.31 thorpej * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
68 1.31 thorpej * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
69 1.31 thorpej * POSSIBILITY OF SUCH DAMAGE.
70 1.31 thorpej */
71 1.31 thorpej
72 1.1 cgd /*
73 1.9 mycroft * Copyright (c) 1982, 1986, 1988, 1993
74 1.9 mycroft * The Regents of the University of California. All rights reserved.
75 1.1 cgd *
76 1.1 cgd * Redistribution and use in source and binary forms, with or without
77 1.1 cgd * modification, are permitted provided that the following conditions
78 1.1 cgd * are met:
79 1.1 cgd * 1. Redistributions of source code must retain the above copyright
80 1.1 cgd * notice, this list of conditions and the following disclaimer.
81 1.1 cgd * 2. Redistributions in binary form must reproduce the above copyright
82 1.1 cgd * notice, this list of conditions and the following disclaimer in the
83 1.1 cgd * documentation and/or other materials provided with the distribution.
84 1.75 agc * 3. Neither the name of the University nor the names of its contributors
85 1.1 cgd * may be used to endorse or promote products derived from this software
86 1.1 cgd * without specific prior written permission.
87 1.1 cgd *
88 1.1 cgd * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
89 1.1 cgd * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
90 1.1 cgd * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
91 1.1 cgd * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
92 1.1 cgd * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
93 1.1 cgd * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
94 1.1 cgd * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
95 1.1 cgd * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
96 1.1 cgd * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
97 1.1 cgd * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
98 1.1 cgd * SUCH DAMAGE.
99 1.1 cgd *
100 1.10 cgd * @(#)ip_icmp.c 8.2 (Berkeley) 1/4/94
101 1.1 cgd */
102 1.66 lukem
103 1.66 lukem #include <sys/cdefs.h>
104 1.116 thorpej __KERNEL_RCSID(0, "$NetBSD: ip_icmp.c,v 1.116 2008/04/12 05:58:22 thorpej Exp $");
105 1.38 thorpej
106 1.38 thorpej #include "opt_ipsec.h"
107 1.1 cgd
108 1.4 mycroft #include <sys/param.h>
109 1.4 mycroft #include <sys/systm.h>
110 1.4 mycroft #include <sys/malloc.h>
111 1.4 mycroft #include <sys/mbuf.h>
112 1.4 mycroft #include <sys/protosw.h>
113 1.4 mycroft #include <sys/socket.h>
114 1.4 mycroft #include <sys/time.h>
115 1.4 mycroft #include <sys/kernel.h>
116 1.63 kml #include <sys/syslog.h>
117 1.19 christos #include <sys/sysctl.h>
118 1.1 cgd
119 1.9 mycroft #include <net/if.h>
120 1.4 mycroft #include <net/route.h>
121 1.1 cgd
122 1.4 mycroft #include <netinet/in.h>
123 1.4 mycroft #include <netinet/in_systm.h>
124 1.4 mycroft #include <netinet/in_var.h>
125 1.4 mycroft #include <netinet/ip.h>
126 1.4 mycroft #include <netinet/ip_icmp.h>
127 1.19 christos #include <netinet/ip_var.h>
128 1.39 sommerfe #include <netinet/in_pcb.h>
129 1.92 yamt #include <netinet/in_proto.h>
130 1.4 mycroft #include <netinet/icmp_var.h>
131 1.116 thorpej #include <netinet/icmp_private.h>
132 1.1 cgd
133 1.37 itojun #ifdef IPSEC
134 1.37 itojun #include <netinet6/ipsec.h>
135 1.37 itojun #include <netkey/key.h>
136 1.37 itojun #endif
137 1.37 itojun
138 1.76 jonathan #ifdef FAST_IPSEC
139 1.76 jonathan #include <netipsec/ipsec.h>
140 1.76 jonathan #include <netipsec/key.h>
141 1.76 jonathan #endif /* FAST_IPSEC*/
142 1.76 jonathan
143 1.19 christos #include <machine/stdarg.h>
144 1.19 christos
145 1.1 cgd /*
146 1.1 cgd * ICMP routines: error generation, receive packet processing, and
147 1.1 cgd * routines to turnaround packets back to the originator, and
148 1.1 cgd * host table maintenance routines.
149 1.1 cgd */
150 1.9 mycroft
151 1.9 mycroft int icmpmaskrepl = 0;
152 1.1 cgd #ifdef ICMPPRINTFS
153 1.1 cgd int icmpprintfs = 0;
154 1.1 cgd #endif
155 1.47 darrenr int icmpreturndatabytes = 8;
156 1.1 cgd
157 1.116 thorpej percpu_t *icmpstat_percpu;
158 1.87 cube
159 1.55 thorpej /*
160 1.55 thorpej * List of callbacks to notify when Path MTU changes are made.
161 1.55 thorpej */
162 1.57 itojun struct icmp_mtudisc_callback {
163 1.57 itojun LIST_ENTRY(icmp_mtudisc_callback) mc_list;
164 1.89 perry void (*mc_func)(struct in_addr);
165 1.55 thorpej };
166 1.55 thorpej
167 1.57 itojun LIST_HEAD(, icmp_mtudisc_callback) icmp_mtudisc_callbacks =
168 1.55 thorpej LIST_HEAD_INITIALIZER(&icmp_mtudisc_callbacks);
169 1.55 thorpej
170 1.37 itojun #if 0
171 1.98 matt static u_int ip_next_mtu(u_int, int);
172 1.37 itojun #else
173 1.98 matt /*static*/ u_int ip_next_mtu(u_int, int);
174 1.37 itojun #endif
175 1.37 itojun
176 1.51 itojun extern int icmperrppslim;
177 1.51 itojun static int icmperrpps_count = 0;
178 1.51 itojun static struct timeval icmperrppslim_last;
179 1.63 kml static int icmp_rediraccept = 1;
180 1.68 itojun static int icmp_redirtimeout = 600;
181 1.63 kml static struct rttimer_queue *icmp_redirect_timeout_q = NULL;
182 1.40 thorpej
183 1.89 perry static void icmp_mtudisc_timeout(struct rtentry *, struct rttimer *);
184 1.89 perry static void icmp_redirect_timeout(struct rtentry *, struct rttimer *);
185 1.24 kml
186 1.89 perry static int icmp_ratelimit(const struct in_addr *, const int, const int);
187 1.40 thorpej
188 1.63 kml
189 1.63 kml void
190 1.90 perry icmp_init(void)
191 1.63 kml {
192 1.67 itojun /*
193 1.67 itojun * This is only useful if the user initializes redirtimeout to
194 1.63 kml * something other than zero.
195 1.63 kml */
196 1.63 kml if (icmp_redirtimeout != 0) {
197 1.67 itojun icmp_redirect_timeout_q =
198 1.63 kml rt_timer_queue_create(icmp_redirtimeout);
199 1.63 kml }
200 1.116 thorpej
201 1.116 thorpej icmpstat_percpu = percpu_alloc(sizeof(uint64_t) * ICMP_NSTATS);
202 1.63 kml }
203 1.63 kml
204 1.1 cgd /*
205 1.55 thorpej * Register a Path MTU Discovery callback.
206 1.55 thorpej */
207 1.55 thorpej void
208 1.90 perry icmp_mtudisc_callback_register(void (*func)(struct in_addr))
209 1.55 thorpej {
210 1.57 itojun struct icmp_mtudisc_callback *mc;
211 1.55 thorpej
212 1.55 thorpej for (mc = LIST_FIRST(&icmp_mtudisc_callbacks); mc != NULL;
213 1.55 thorpej mc = LIST_NEXT(mc, mc_list)) {
214 1.55 thorpej if (mc->mc_func == func)
215 1.55 thorpej return;
216 1.55 thorpej }
217 1.55 thorpej
218 1.55 thorpej mc = malloc(sizeof(*mc), M_PCB, M_NOWAIT);
219 1.55 thorpej if (mc == NULL)
220 1.55 thorpej panic("icmp_mtudisc_callback_register");
221 1.55 thorpej
222 1.55 thorpej mc->mc_func = func;
223 1.55 thorpej LIST_INSERT_HEAD(&icmp_mtudisc_callbacks, mc, mc_list);
224 1.55 thorpej }
225 1.55 thorpej
226 1.55 thorpej /*
227 1.1 cgd * Generate an error packet of type error
228 1.1 cgd * in response to bad packet ip.
229 1.1 cgd */
230 1.6 mycroft void
231 1.90 perry icmp_error(struct mbuf *n, int type, int code, n_long dest,
232 1.96 christos int destmtu)
233 1.1 cgd {
234 1.44 augustss struct ip *oip = mtod(n, struct ip *), *nip;
235 1.44 augustss unsigned oiplen = oip->ip_hl << 2;
236 1.44 augustss struct icmp *icp;
237 1.44 augustss struct mbuf *m;
238 1.100 peter struct m_tag *mtag;
239 1.52 sommerfe unsigned icmplen, mblen;
240 1.1 cgd
241 1.1 cgd #ifdef ICMPPRINTFS
242 1.1 cgd if (icmpprintfs)
243 1.101 peter printf("icmp_error(%p, type:%d, code:%d)\n", oip, type, code);
244 1.1 cgd #endif
245 1.1 cgd if (type != ICMP_REDIRECT)
246 1.116 thorpej ICMP_STATINC(ICMP_STAT_ERROR);
247 1.1 cgd /*
248 1.42 itojun * Don't send error if the original packet was encrypted.
249 1.1 cgd * Don't send error if not the first fragment of message.
250 1.1 cgd * Don't error if the old packet protocol was ICMP
251 1.1 cgd * error message, only known informational types.
252 1.1 cgd */
253 1.42 itojun if (n->m_flags & M_DECRYPTED)
254 1.42 itojun goto freeit;
255 1.70 itojun if (oip->ip_off &~ htons(IP_MF|IP_DF))
256 1.1 cgd goto freeit;
257 1.1 cgd if (oip->ip_p == IPPROTO_ICMP && type != ICMP_REDIRECT &&
258 1.1 cgd n->m_len >= oiplen + ICMP_MINLEN &&
259 1.111 christos !ICMP_INFOTYPE(((struct icmp *)((char *)oip + oiplen))->icmp_type)) {
260 1.116 thorpej ICMP_STATINC(ICMP_STAT_OLDICMP);
261 1.1 cgd goto freeit;
262 1.1 cgd }
263 1.3 hpeyerl /* Don't send error in response to a multicast or broadcast packet */
264 1.9 mycroft if (n->m_flags & (M_BCAST|M_MCAST))
265 1.3 hpeyerl goto freeit;
266 1.40 thorpej
267 1.1 cgd /*
268 1.40 thorpej * First, do a rate limitation check.
269 1.40 thorpej */
270 1.40 thorpej if (icmp_ratelimit(&oip->ip_src, type, code)) {
271 1.40 thorpej /* XXX stat */
272 1.40 thorpej goto freeit;
273 1.40 thorpej }
274 1.40 thorpej
275 1.40 thorpej /*
276 1.40 thorpej * Now, formulate icmp message
277 1.1 cgd */
278 1.70 itojun icmplen = oiplen + min(icmpreturndatabytes,
279 1.70 itojun ntohs(oip->ip_len) - oiplen);
280 1.52 sommerfe /*
281 1.74 itojun * Defend against mbuf chains shorter than oip->ip_len - oiplen:
282 1.52 sommerfe */
283 1.52 sommerfe mblen = 0;
284 1.52 sommerfe for (m = n; m && (mblen < icmplen); m = m->m_next)
285 1.52 sommerfe mblen += m->m_len;
286 1.52 sommerfe icmplen = min(mblen, icmplen);
287 1.52 sommerfe
288 1.52 sommerfe /*
289 1.52 sommerfe * As we are not required to return everything we have,
290 1.52 sommerfe * we return whatever we can return at ease.
291 1.52 sommerfe *
292 1.52 sommerfe * Note that ICMP datagrams longer than 576 octets are out of spec
293 1.52 sommerfe * according to RFC1812; the limit on icmpreturndatabytes below in
294 1.52 sommerfe * icmp_sysctl will keep things below that limit.
295 1.52 sommerfe */
296 1.52 sommerfe
297 1.52 sommerfe KASSERT(ICMP_MINLEN <= MCLBYTES);
298 1.52 sommerfe
299 1.52 sommerfe if (icmplen + ICMP_MINLEN > MCLBYTES)
300 1.52 sommerfe icmplen = MCLBYTES - ICMP_MINLEN;
301 1.52 sommerfe
302 1.1 cgd m = m_gethdr(M_DONTWAIT, MT_HEADER);
303 1.52 sommerfe if (m && (icmplen + ICMP_MINLEN > MHLEN)) {
304 1.52 sommerfe MCLGET(m, M_DONTWAIT);
305 1.52 sommerfe if ((m->m_flags & M_EXT) == 0) {
306 1.52 sommerfe m_freem(m);
307 1.52 sommerfe m = NULL;
308 1.52 sommerfe }
309 1.52 sommerfe }
310 1.1 cgd if (m == NULL)
311 1.1 cgd goto freeit;
312 1.72 matt MCLAIM(m, n->m_owner);
313 1.1 cgd m->m_len = icmplen + ICMP_MINLEN;
314 1.52 sommerfe if ((m->m_flags & M_EXT) == 0)
315 1.52 sommerfe MH_ALIGN(m, m->m_len);
316 1.1 cgd icp = mtod(m, struct icmp *);
317 1.1 cgd if ((u_int)type > ICMP_MAXTYPE)
318 1.1 cgd panic("icmp_error");
319 1.116 thorpej ICMP_STATINC(ICMP_STAT_OUTHIST + type);
320 1.1 cgd icp->icmp_type = type;
321 1.1 cgd if (type == ICMP_REDIRECT)
322 1.9 mycroft icp->icmp_gwaddr.s_addr = dest;
323 1.9 mycroft else {
324 1.1 cgd icp->icmp_void = 0;
325 1.67 itojun /*
326 1.9 mycroft * The following assignments assume an overlay with the
327 1.9 mycroft * zeroed icmp_void field.
328 1.9 mycroft */
329 1.9 mycroft if (type == ICMP_PARAMPROB) {
330 1.9 mycroft icp->icmp_pptr = code;
331 1.9 mycroft code = 0;
332 1.9 mycroft } else if (type == ICMP_UNREACH &&
333 1.96 christos code == ICMP_UNREACH_NEEDFRAG && destmtu)
334 1.96 christos icp->icmp_nextmtu = htons(destmtu);
335 1.1 cgd }
336 1.9 mycroft
337 1.1 cgd icp->icmp_code = code;
338 1.111 christos m_copydata(n, 0, icmplen, (void *)&icp->icmp_ip);
339 1.1 cgd
340 1.1 cgd /*
341 1.1 cgd * Now, copy old ip header (without options)
342 1.1 cgd * in front of icmp message.
343 1.1 cgd */
344 1.1 cgd if (m->m_data - sizeof(struct ip) < m->m_pktdat)
345 1.1 cgd panic("icmp len");
346 1.1 cgd m->m_data -= sizeof(struct ip);
347 1.1 cgd m->m_len += sizeof(struct ip);
348 1.1 cgd m->m_pkthdr.len = m->m_len;
349 1.1 cgd m->m_pkthdr.rcvif = n->m_pkthdr.rcvif;
350 1.1 cgd nip = mtod(m, struct ip *);
351 1.47 darrenr /* ip_v set in ip_output */
352 1.47 darrenr nip->ip_hl = sizeof(struct ip) >> 2;
353 1.47 darrenr nip->ip_tos = 0;
354 1.70 itojun nip->ip_len = htons(m->m_len);
355 1.47 darrenr /* ip_id set in ip_output */
356 1.70 itojun nip->ip_off = htons(0);
357 1.47 darrenr /* ip_ttl set in icmp_reflect */
358 1.1 cgd nip->ip_p = IPPROTO_ICMP;
359 1.47 darrenr nip->ip_src = oip->ip_src;
360 1.47 darrenr nip->ip_dst = oip->ip_dst;
361 1.100 peter /* move PF_GENERATED m_tag to new packet, if it exists */
362 1.100 peter mtag = m_tag_find(n, PACKET_TAG_PF_GENERATED, NULL);
363 1.100 peter if (mtag != NULL) {
364 1.100 peter m_tag_unlink(n, mtag);
365 1.100 peter m_tag_prepend(m, mtag);
366 1.100 peter }
367 1.1 cgd icmp_reflect(m);
368 1.1 cgd
369 1.1 cgd freeit:
370 1.1 cgd m_freem(n);
371 1.1 cgd }
372 1.1 cgd
373 1.103 christos struct sockaddr_in icmpsrc = {
374 1.103 christos .sin_len = sizeof (struct sockaddr_in),
375 1.103 christos .sin_family = AF_INET,
376 1.103 christos };
377 1.103 christos static struct sockaddr_in icmpdst = {
378 1.103 christos .sin_len = sizeof (struct sockaddr_in),
379 1.103 christos .sin_family = AF_INET,
380 1.103 christos };
381 1.103 christos static struct sockaddr_in icmpgw = {
382 1.103 christos .sin_len = sizeof (struct sockaddr_in),
383 1.103 christos .sin_family = AF_INET,
384 1.103 christos };
385 1.103 christos struct sockaddr_in icmpmask = {
386 1.103 christos .sin_len = 8,
387 1.103 christos .sin_family = 0,
388 1.103 christos };
389 1.1 cgd
390 1.1 cgd /*
391 1.1 cgd * Process a received ICMP message.
392 1.1 cgd */
393 1.6 mycroft void
394 1.19 christos icmp_input(struct mbuf *m, ...)
395 1.1 cgd {
396 1.37 itojun int proto;
397 1.44 augustss struct icmp *icp;
398 1.44 augustss struct ip *ip = mtod(m, struct ip *);
399 1.34 mycroft int icmplen;
400 1.44 augustss int i;
401 1.1 cgd struct in_ifaddr *ia;
402 1.109 dyoung void *(*ctlfunc)(int, const struct sockaddr *, void *);
403 1.9 mycroft int code;
404 1.19 christos int hlen;
405 1.19 christos va_list ap;
406 1.63 kml struct rtentry *rt;
407 1.19 christos
408 1.19 christos va_start(ap, m);
409 1.19 christos hlen = va_arg(ap, int);
410 1.37 itojun proto = va_arg(ap, int);
411 1.19 christos va_end(ap);
412 1.1 cgd
413 1.1 cgd /*
414 1.1 cgd * Locate icmp structure in mbuf, and check
415 1.1 cgd * that not corrupted and of at least minimum length.
416 1.1 cgd */
417 1.70 itojun icmplen = ntohs(ip->ip_len) - hlen;
418 1.1 cgd #ifdef ICMPPRINTFS
419 1.95 christos if (icmpprintfs) {
420 1.95 christos printf("icmp_input from `%s' to ", inet_ntoa(ip->ip_src));
421 1.95 christos printf("`%s', len %d\n", inet_ntoa(ip->ip_dst), icmplen);
422 1.95 christos }
423 1.1 cgd #endif
424 1.1 cgd if (icmplen < ICMP_MINLEN) {
425 1.116 thorpej ICMP_STATINC(ICMP_STAT_TOOSHORT);
426 1.1 cgd goto freeit;
427 1.1 cgd }
428 1.9 mycroft i = hlen + min(icmplen, ICMP_ADVLENMIN);
429 1.99 dyoung if ((m->m_len < i || M_READONLY(m)) && (m = m_pullup(m, i)) == 0) {
430 1.116 thorpej ICMP_STATINC(ICMP_STAT_TOOSHORT);
431 1.1 cgd return;
432 1.1 cgd }
433 1.5 mycroft ip = mtod(m, struct ip *);
434 1.1 cgd m->m_len -= hlen;
435 1.1 cgd m->m_data += hlen;
436 1.1 cgd icp = mtod(m, struct icmp *);
437 1.69 thorpej /* Don't need to assert alignment, here. */
438 1.1 cgd if (in_cksum(m, icmplen)) {
439 1.116 thorpej ICMP_STATINC(ICMP_STAT_CHECKSUM);
440 1.1 cgd goto freeit;
441 1.1 cgd }
442 1.1 cgd m->m_len += hlen;
443 1.1 cgd m->m_data -= hlen;
444 1.1 cgd
445 1.1 cgd #ifdef ICMPPRINTFS
446 1.1 cgd /*
447 1.1 cgd * Message type specific processing.
448 1.1 cgd */
449 1.1 cgd if (icmpprintfs)
450 1.95 christos printf("icmp_input(type:%d, code:%d)\n", icp->icmp_type,
451 1.1 cgd icp->icmp_code);
452 1.37 itojun #endif
453 1.1 cgd if (icp->icmp_type > ICMP_MAXTYPE)
454 1.1 cgd goto raw;
455 1.116 thorpej ICMP_STATINC(ICMP_STAT_INHIST + icp->icmp_type);
456 1.1 cgd code = icp->icmp_code;
457 1.1 cgd switch (icp->icmp_type) {
458 1.1 cgd
459 1.1 cgd case ICMP_UNREACH:
460 1.9 mycroft switch (code) {
461 1.9 mycroft case ICMP_UNREACH_NET:
462 1.102 yamt code = PRC_UNREACH_NET;
463 1.102 yamt break;
464 1.102 yamt
465 1.9 mycroft case ICMP_UNREACH_HOST:
466 1.102 yamt code = PRC_UNREACH_HOST;
467 1.102 yamt break;
468 1.102 yamt
469 1.9 mycroft case ICMP_UNREACH_PROTOCOL:
470 1.102 yamt code = PRC_UNREACH_PROTOCOL;
471 1.102 yamt break;
472 1.102 yamt
473 1.9 mycroft case ICMP_UNREACH_PORT:
474 1.102 yamt code = PRC_UNREACH_PORT;
475 1.102 yamt break;
476 1.102 yamt
477 1.9 mycroft case ICMP_UNREACH_SRCFAIL:
478 1.102 yamt code = PRC_UNREACH_SRCFAIL;
479 1.9 mycroft break;
480 1.9 mycroft
481 1.9 mycroft case ICMP_UNREACH_NEEDFRAG:
482 1.9 mycroft code = PRC_MSGSIZE;
483 1.9 mycroft break;
484 1.67 itojun
485 1.9 mycroft case ICMP_UNREACH_NET_UNKNOWN:
486 1.9 mycroft case ICMP_UNREACH_NET_PROHIB:
487 1.9 mycroft case ICMP_UNREACH_TOSNET:
488 1.9 mycroft code = PRC_UNREACH_NET;
489 1.9 mycroft break;
490 1.9 mycroft
491 1.9 mycroft case ICMP_UNREACH_HOST_UNKNOWN:
492 1.9 mycroft case ICMP_UNREACH_ISOLATED:
493 1.9 mycroft case ICMP_UNREACH_HOST_PROHIB:
494 1.9 mycroft case ICMP_UNREACH_TOSHOST:
495 1.9 mycroft code = PRC_UNREACH_HOST;
496 1.9 mycroft break;
497 1.9 mycroft
498 1.9 mycroft default:
499 1.9 mycroft goto badcode;
500 1.9 mycroft }
501 1.1 cgd goto deliver;
502 1.1 cgd
503 1.1 cgd case ICMP_TIMXCEED:
504 1.1 cgd if (code > 1)
505 1.1 cgd goto badcode;
506 1.1 cgd code += PRC_TIMXCEED_INTRANS;
507 1.1 cgd goto deliver;
508 1.1 cgd
509 1.1 cgd case ICMP_PARAMPROB:
510 1.9 mycroft if (code > 1)
511 1.1 cgd goto badcode;
512 1.1 cgd code = PRC_PARAMPROB;
513 1.1 cgd goto deliver;
514 1.1 cgd
515 1.1 cgd case ICMP_SOURCEQUENCH:
516 1.1 cgd if (code)
517 1.1 cgd goto badcode;
518 1.1 cgd code = PRC_QUENCH;
519 1.20 mycroft goto deliver;
520 1.20 mycroft
521 1.1 cgd deliver:
522 1.1 cgd /*
523 1.1 cgd * Problem with datagram; advise higher level routines.
524 1.1 cgd */
525 1.1 cgd if (icmplen < ICMP_ADVLENMIN || icmplen < ICMP_ADVLEN(icp) ||
526 1.1 cgd icp->icmp_ip.ip_hl < (sizeof(struct ip) >> 2)) {
527 1.116 thorpej ICMP_STATINC(ICMP_STAT_BADLEN);
528 1.1 cgd goto freeit;
529 1.1 cgd }
530 1.14 mycroft if (IN_MULTICAST(icp->icmp_ip.ip_dst.s_addr))
531 1.13 mycroft goto badcode;
532 1.1 cgd #ifdef ICMPPRINTFS
533 1.1 cgd if (icmpprintfs)
534 1.22 christos printf("deliver to protocol %d\n", icp->icmp_ip.ip_p);
535 1.1 cgd #endif
536 1.1 cgd icmpsrc.sin_addr = icp->icmp_ip.ip_dst;
537 1.19 christos ctlfunc = inetsw[ip_protox[icp->icmp_ip.ip_p]].pr_ctlinput;
538 1.19 christos if (ctlfunc)
539 1.55 thorpej (void) (*ctlfunc)(code, sintosa(&icmpsrc),
540 1.55 thorpej &icp->icmp_ip);
541 1.1 cgd break;
542 1.1 cgd
543 1.1 cgd badcode:
544 1.116 thorpej ICMP_STATINC(ICMP_STAT_BADCODE);
545 1.1 cgd break;
546 1.1 cgd
547 1.1 cgd case ICMP_ECHO:
548 1.1 cgd icp->icmp_type = ICMP_ECHOREPLY;
549 1.1 cgd goto reflect;
550 1.1 cgd
551 1.1 cgd case ICMP_TSTAMP:
552 1.1 cgd if (icmplen < ICMP_TSLEN) {
553 1.116 thorpej ICMP_STATINC(ICMP_STAT_BADLEN);
554 1.1 cgd break;
555 1.1 cgd }
556 1.1 cgd icp->icmp_type = ICMP_TSTAMPREPLY;
557 1.1 cgd icp->icmp_rtime = iptime();
558 1.1 cgd icp->icmp_ttime = icp->icmp_rtime; /* bogus, do later! */
559 1.1 cgd goto reflect;
560 1.67 itojun
561 1.9 mycroft case ICMP_MASKREQ:
562 1.9 mycroft if (icmpmaskrepl == 0)
563 1.9 mycroft break;
564 1.9 mycroft /*
565 1.9 mycroft * We are not able to respond with all ones broadcast
566 1.9 mycroft * unless we receive it over a point-to-point interface.
567 1.9 mycroft */
568 1.23 thorpej if (icmplen < ICMP_MASKLEN) {
569 1.116 thorpej ICMP_STATINC(ICMP_STAT_BADLEN);
570 1.9 mycroft break;
571 1.23 thorpej }
572 1.15 mycroft if (ip->ip_dst.s_addr == INADDR_BROADCAST ||
573 1.20 mycroft in_nullhost(ip->ip_dst))
574 1.9 mycroft icmpdst.sin_addr = ip->ip_src;
575 1.15 mycroft else
576 1.9 mycroft icmpdst.sin_addr = ip->ip_dst;
577 1.16 mycroft ia = ifatoia(ifaof_ifpforaddr(sintosa(&icmpdst),
578 1.16 mycroft m->m_pkthdr.rcvif));
579 1.9 mycroft if (ia == 0)
580 1.1 cgd break;
581 1.1 cgd icp->icmp_type = ICMP_MASKREPLY;
582 1.1 cgd icp->icmp_mask = ia->ia_sockmask.sin_addr.s_addr;
583 1.20 mycroft if (in_nullhost(ip->ip_src)) {
584 1.1 cgd if (ia->ia_ifp->if_flags & IFF_BROADCAST)
585 1.17 mycroft ip->ip_src = ia->ia_broadaddr.sin_addr;
586 1.1 cgd else if (ia->ia_ifp->if_flags & IFF_POINTOPOINT)
587 1.17 mycroft ip->ip_src = ia->ia_dstaddr.sin_addr;
588 1.1 cgd }
589 1.1 cgd reflect:
590 1.116 thorpej {
591 1.116 thorpej uint64_t *icps = percpu_getref(icmpstat_percpu);
592 1.116 thorpej icps[ICMP_STAT_REFLECT]++;
593 1.116 thorpej icps[ICMP_STAT_OUTHIST + icp->icmp_type]++;
594 1.116 thorpej percpu_putref(icmpstat_percpu);
595 1.116 thorpej }
596 1.1 cgd icmp_reflect(m);
597 1.1 cgd return;
598 1.1 cgd
599 1.1 cgd case ICMP_REDIRECT:
600 1.9 mycroft if (code > 3)
601 1.9 mycroft goto badcode;
602 1.63 kml if (icmp_rediraccept == 0)
603 1.63 kml goto freeit;
604 1.9 mycroft if (icmplen < ICMP_ADVLENMIN || icmplen < ICMP_ADVLEN(icp) ||
605 1.9 mycroft icp->icmp_ip.ip_hl < (sizeof(struct ip) >> 2)) {
606 1.116 thorpej ICMP_STATINC(ICMP_STAT_BADLEN);
607 1.1 cgd break;
608 1.1 cgd }
609 1.1 cgd /*
610 1.1 cgd * Short circuit routing redirects to force
611 1.1 cgd * immediate change in the kernel's routing
612 1.1 cgd * tables. The message is also handed to anyone
613 1.1 cgd * listening on a raw socket (e.g. the routing
614 1.1 cgd * daemon for use in updating its tables).
615 1.1 cgd */
616 1.1 cgd icmpgw.sin_addr = ip->ip_src;
617 1.1 cgd icmpdst.sin_addr = icp->icmp_gwaddr;
618 1.1 cgd #ifdef ICMPPRINTFS
619 1.95 christos if (icmpprintfs) {
620 1.101 peter printf("redirect dst `%s' to `%s'\n",
621 1.101 peter inet_ntoa(icp->icmp_ip.ip_dst),
622 1.101 peter inet_ntoa(icp->icmp_gwaddr));
623 1.95 christos }
624 1.1 cgd #endif
625 1.9 mycroft icmpsrc.sin_addr = icp->icmp_ip.ip_dst;
626 1.63 kml rt = NULL;
627 1.16 mycroft rtredirect(sintosa(&icmpsrc), sintosa(&icmpdst),
628 1.113 dyoung NULL, RTF_GATEWAY | RTF_HOST, sintosa(&icmpgw), &rt);
629 1.63 kml if (rt != NULL && icmp_redirtimeout != 0) {
630 1.67 itojun i = rt_timer_add(rt, icmp_redirect_timeout,
631 1.63 kml icmp_redirect_timeout_q);
632 1.63 kml if (i)
633 1.63 kml log(LOG_ERR, "ICMP: redirect failed to "
634 1.63 kml "register timeout for route to %x, "
635 1.67 itojun "code %d\n",
636 1.63 kml icp->icmp_ip.ip_dst.s_addr, i);
637 1.63 kml }
638 1.63 kml if (rt != NULL)
639 1.63 kml rtfree(rt);
640 1.63 kml
641 1.16 mycroft pfctlinput(PRC_REDIRECT_HOST, sintosa(&icmpsrc));
642 1.76 jonathan #if defined(IPSEC) || defined(FAST_IPSEC)
643 1.37 itojun key_sa_routechange((struct sockaddr *)&icmpsrc);
644 1.37 itojun #endif
645 1.1 cgd break;
646 1.1 cgd
647 1.1 cgd /*
648 1.1 cgd * No kernel processing for the following;
649 1.1 cgd * just fall through to send to raw listener.
650 1.1 cgd */
651 1.1 cgd case ICMP_ECHOREPLY:
652 1.9 mycroft case ICMP_ROUTERADVERT:
653 1.9 mycroft case ICMP_ROUTERSOLICIT:
654 1.1 cgd case ICMP_TSTAMPREPLY:
655 1.1 cgd case ICMP_IREQREPLY:
656 1.1 cgd case ICMP_MASKREPLY:
657 1.1 cgd default:
658 1.1 cgd break;
659 1.1 cgd }
660 1.1 cgd
661 1.1 cgd raw:
662 1.37 itojun rip_input(m, hlen, proto);
663 1.1 cgd return;
664 1.1 cgd
665 1.1 cgd freeit:
666 1.1 cgd m_freem(m);
667 1.37 itojun return;
668 1.1 cgd }
669 1.1 cgd
670 1.1 cgd /*
671 1.1 cgd * Reflect the ip packet back to the source
672 1.1 cgd */
673 1.6 mycroft void
674 1.90 perry icmp_reflect(struct mbuf *m)
675 1.1 cgd {
676 1.44 augustss struct ip *ip = mtod(m, struct ip *);
677 1.44 augustss struct in_ifaddr *ia;
678 1.44 augustss struct ifaddr *ifa;
679 1.39 sommerfe struct sockaddr_in *sin = 0;
680 1.1 cgd struct in_addr t;
681 1.19 christos struct mbuf *opts = 0;
682 1.1 cgd int optlen = (ip->ip_hl << 2) - sizeof(struct ip);
683 1.1 cgd
684 1.9 mycroft if (!in_canforward(ip->ip_src) &&
685 1.14 mycroft ((ip->ip_src.s_addr & IN_CLASSA_NET) !=
686 1.14 mycroft htonl(IN_LOOPBACKNET << IN_CLASSA_NSHIFT))) {
687 1.9 mycroft m_freem(m); /* Bad return address */
688 1.12 cgd goto done; /* ip_output() will check for broadcast */
689 1.9 mycroft }
690 1.1 cgd t = ip->ip_dst;
691 1.1 cgd ip->ip_dst = ip->ip_src;
692 1.1 cgd /*
693 1.39 sommerfe * If the incoming packet was addressed directly to us, use
694 1.39 sommerfe * dst as the src for the reply. Otherwise (broadcast or
695 1.39 sommerfe * anonymous), use an address which corresponds to the
696 1.39 sommerfe * incoming interface, with a preference for the address which
697 1.39 sommerfe * corresponds to the route to the destination of the ICMP.
698 1.1 cgd */
699 1.39 sommerfe
700 1.39 sommerfe /* Look for packet addressed to us */
701 1.27 tls INADDR_TO_IA(t, ia);
702 1.39 sommerfe
703 1.39 sommerfe /* look for packet sent to broadcast address */
704 1.85 itojun if (ia == NULL && m->m_pkthdr.rcvif &&
705 1.85 itojun (m->m_pkthdr.rcvif->if_flags & IFF_BROADCAST)) {
706 1.88 matt IFADDR_FOREACH(ifa, m->m_pkthdr.rcvif) {
707 1.27 tls if (ifa->ifa_addr->sa_family != AF_INET)
708 1.27 tls continue;
709 1.39 sommerfe if (in_hosteq(t,ifatoia(ifa)->ia_broadaddr.sin_addr)) {
710 1.39 sommerfe ia = ifatoia(ifa);
711 1.27 tls break;
712 1.39 sommerfe }
713 1.27 tls }
714 1.1 cgd }
715 1.27 tls
716 1.39 sommerfe if (ia)
717 1.39 sommerfe sin = &ia->ia_addr;
718 1.39 sommerfe
719 1.9 mycroft icmpdst.sin_addr = t;
720 1.39 sommerfe
721 1.70 itojun /*
722 1.70 itojun * if the packet is addressed somewhere else, compute the
723 1.70 itojun * source address for packets routed back to the source, and
724 1.70 itojun * use that, if it's an address on the interface which
725 1.70 itojun * received the packet
726 1.70 itojun */
727 1.114 dyoung if (sin == NULL && m->m_pkthdr.rcvif) {
728 1.39 sommerfe struct sockaddr_in sin_dst;
729 1.39 sommerfe struct route icmproute;
730 1.39 sommerfe int errornum;
731 1.39 sommerfe
732 1.114 dyoung sockaddr_in_init(&sin_dst, &ip->ip_dst, 0);
733 1.108 dyoung memset(&icmproute, 0, sizeof(icmproute));
734 1.39 sommerfe errornum = 0;
735 1.39 sommerfe sin = in_selectsrc(&sin_dst, &icmproute, 0, NULL, &errornum);
736 1.39 sommerfe /* errornum is never used */
737 1.107 joerg rtcache_free(&icmproute);
738 1.39 sommerfe /* check to make sure sin is a source address on rcvif */
739 1.39 sommerfe if (sin) {
740 1.39 sommerfe t = sin->sin_addr;
741 1.114 dyoung sin = NULL;
742 1.39 sommerfe INADDR_TO_IA(t, ia);
743 1.39 sommerfe while (ia) {
744 1.39 sommerfe if (ia->ia_ifp == m->m_pkthdr.rcvif) {
745 1.39 sommerfe sin = &ia->ia_addr;
746 1.39 sommerfe break;
747 1.39 sommerfe }
748 1.39 sommerfe NEXT_IA_WITH_SAME_ADDR(ia);
749 1.39 sommerfe }
750 1.39 sommerfe }
751 1.39 sommerfe }
752 1.39 sommerfe
753 1.70 itojun /*
754 1.70 itojun * if it was not addressed to us, but the route doesn't go out
755 1.70 itojun * the source interface, pick an address on the source
756 1.70 itojun * interface. This can happen when routing is asymmetric, or
757 1.70 itojun * when the incoming packet was encapsulated
758 1.70 itojun */
759 1.114 dyoung if (sin == NULL && m->m_pkthdr.rcvif) {
760 1.88 matt IFADDR_FOREACH(ifa, m->m_pkthdr.rcvif) {
761 1.39 sommerfe if (ifa->ifa_addr->sa_family != AF_INET)
762 1.39 sommerfe continue;
763 1.39 sommerfe sin = &(ifatoia(ifa)->ia_addr);
764 1.39 sommerfe break;
765 1.39 sommerfe }
766 1.39 sommerfe }
767 1.39 sommerfe
768 1.9 mycroft /*
769 1.9 mycroft * The following happens if the packet was not addressed to us,
770 1.27 tls * and was received on an interface with no IP address:
771 1.27 tls * We find the first AF_INET address on the first non-loopback
772 1.27 tls * interface.
773 1.9 mycroft */
774 1.114 dyoung if (sin == NULL)
775 1.79 jonathan TAILQ_FOREACH(ia, &in_ifaddrhead, ia_list) {
776 1.27 tls if (ia->ia_ifp->if_flags & IFF_LOOPBACK)
777 1.27 tls continue;
778 1.39 sommerfe sin = &ia->ia_addr;
779 1.27 tls break;
780 1.27 tls }
781 1.39 sommerfe
782 1.36 mycroft /*
783 1.36 mycroft * If we still didn't find an address, punt. We could have an
784 1.36 mycroft * interface up (and receiving packets) with no address.
785 1.36 mycroft */
786 1.114 dyoung if (sin == NULL) {
787 1.36 mycroft m_freem(m);
788 1.36 mycroft goto done;
789 1.36 mycroft }
790 1.36 mycroft
791 1.39 sommerfe ip->ip_src = sin->sin_addr;
792 1.1 cgd ip->ip_ttl = MAXTTL;
793 1.1 cgd
794 1.1 cgd if (optlen > 0) {
795 1.44 augustss u_char *cp;
796 1.1 cgd int opt, cnt;
797 1.1 cgd u_int len;
798 1.1 cgd
799 1.1 cgd /*
800 1.1 cgd * Retrieve any source routing from the incoming packet;
801 1.1 cgd * add on any record-route or timestamp options.
802 1.1 cgd */
803 1.1 cgd cp = (u_char *) (ip + 1);
804 1.1 cgd if ((opts = ip_srcroute()) == 0 &&
805 1.1 cgd (opts = m_gethdr(M_DONTWAIT, MT_HEADER))) {
806 1.72 matt MCLAIM(opts, m->m_owner);
807 1.1 cgd opts->m_len = sizeof(struct in_addr);
808 1.20 mycroft *mtod(opts, struct in_addr *) = zeroin_addr;
809 1.1 cgd }
810 1.1 cgd if (opts) {
811 1.1 cgd #ifdef ICMPPRINTFS
812 1.1 cgd if (icmpprintfs)
813 1.22 christos printf("icmp_reflect optlen %d rt %d => ",
814 1.1 cgd optlen, opts->m_len);
815 1.1 cgd #endif
816 1.1 cgd for (cnt = optlen; cnt > 0; cnt -= len, cp += len) {
817 1.1 cgd opt = cp[IPOPT_OPTVAL];
818 1.1 cgd if (opt == IPOPT_EOL)
819 1.1 cgd break;
820 1.1 cgd if (opt == IPOPT_NOP)
821 1.1 cgd len = 1;
822 1.1 cgd else {
823 1.45 itojun if (cnt < IPOPT_OLEN + sizeof(*cp))
824 1.45 itojun break;
825 1.1 cgd len = cp[IPOPT_OLEN];
826 1.45 itojun if (len < IPOPT_OLEN + sizeof(*cp) ||
827 1.45 itojun len > cnt)
828 1.1 cgd break;
829 1.1 cgd }
830 1.1 cgd /*
831 1.9 mycroft * Should check for overflow, but it "can't happen"
832 1.1 cgd */
833 1.67 itojun if (opt == IPOPT_RR || opt == IPOPT_TS ||
834 1.9 mycroft opt == IPOPT_SECURITY) {
835 1.111 christos memmove(mtod(opts, char *) + opts->m_len,
836 1.111 christos cp, len);
837 1.1 cgd opts->m_len += len;
838 1.1 cgd }
839 1.1 cgd }
840 1.9 mycroft /* Terminate & pad, if necessary */
841 1.19 christos if ((cnt = opts->m_len % 4) != 0) {
842 1.9 mycroft for (; cnt < 4; cnt++) {
843 1.111 christos *(mtod(opts, char *) + opts->m_len) =
844 1.9 mycroft IPOPT_EOL;
845 1.9 mycroft opts->m_len++;
846 1.9 mycroft }
847 1.1 cgd }
848 1.1 cgd #ifdef ICMPPRINTFS
849 1.1 cgd if (icmpprintfs)
850 1.22 christos printf("%d\n", opts->m_len);
851 1.1 cgd #endif
852 1.1 cgd }
853 1.1 cgd /*
854 1.1 cgd * Now strip out original options by copying rest of first
855 1.1 cgd * mbuf's data back, and adjust the IP length.
856 1.1 cgd */
857 1.70 itojun ip->ip_len = htons(ntohs(ip->ip_len) - optlen);
858 1.1 cgd ip->ip_hl = sizeof(struct ip) >> 2;
859 1.1 cgd m->m_len -= optlen;
860 1.1 cgd if (m->m_flags & M_PKTHDR)
861 1.1 cgd m->m_pkthdr.len -= optlen;
862 1.1 cgd optlen += sizeof(struct ip);
863 1.111 christos memmove(ip + 1, (char *)ip + optlen,
864 1.111 christos (unsigned)(m->m_len - sizeof(struct ip)));
865 1.1 cgd }
866 1.80 jonathan m_tag_delete_nonpersistent(m);
867 1.3 hpeyerl m->m_flags &= ~(M_BCAST|M_MCAST);
868 1.73 tron
869 1.91 perry /*
870 1.73 tron * Clear any in-bound checksum flags for this packet.
871 1.73 tron */
872 1.86 itojun if (m->m_flags & M_PKTHDR)
873 1.86 itojun m->m_pkthdr.csum_flags = 0;
874 1.73 tron
875 1.1 cgd icmp_send(m, opts);
876 1.9 mycroft done:
877 1.1 cgd if (opts)
878 1.1 cgd (void)m_free(opts);
879 1.1 cgd }
880 1.1 cgd
881 1.1 cgd /*
882 1.1 cgd * Send an icmp packet back to the ip level,
883 1.1 cgd * after supplying a checksum.
884 1.1 cgd */
885 1.6 mycroft void
886 1.90 perry icmp_send(struct mbuf *m, struct mbuf *opts)
887 1.1 cgd {
888 1.44 augustss struct ip *ip = mtod(m, struct ip *);
889 1.44 augustss int hlen;
890 1.44 augustss struct icmp *icp;
891 1.1 cgd
892 1.1 cgd hlen = ip->ip_hl << 2;
893 1.1 cgd m->m_data += hlen;
894 1.1 cgd m->m_len -= hlen;
895 1.1 cgd icp = mtod(m, struct icmp *);
896 1.1 cgd icp->icmp_cksum = 0;
897 1.70 itojun icp->icmp_cksum = in_cksum(m, ntohs(ip->ip_len) - hlen);
898 1.1 cgd m->m_data -= hlen;
899 1.1 cgd m->m_len += hlen;
900 1.1 cgd #ifdef ICMPPRINTFS
901 1.95 christos if (icmpprintfs) {
902 1.101 peter printf("icmp_send to destination `%s' from `%s'\n",
903 1.101 peter inet_ntoa(ip->ip_dst), inet_ntoa(ip->ip_src));
904 1.95 christos }
905 1.43 itojun #endif
906 1.114 dyoung (void)ip_output(m, opts, NULL, 0, NULL, NULL);
907 1.1 cgd }
908 1.1 cgd
909 1.1 cgd n_time
910 1.90 perry iptime(void)
911 1.1 cgd {
912 1.1 cgd struct timeval atv;
913 1.1 cgd u_long t;
914 1.1 cgd
915 1.1 cgd microtime(&atv);
916 1.1 cgd t = (atv.tv_sec % (24*60*60)) * 1000 + atv.tv_usec / 1000;
917 1.1 cgd return (htonl(t));
918 1.9 mycroft }
919 1.9 mycroft
920 1.81 atatat /*
921 1.81 atatat * sysctl helper routine for net.inet.icmp.returndatabytes. ensures
922 1.81 atatat * that the new value is in the correct range.
923 1.81 atatat */
924 1.81 atatat static int
925 1.81 atatat sysctl_net_inet_icmp_returndatabytes(SYSCTLFN_ARGS)
926 1.81 atatat {
927 1.81 atatat int error, t;
928 1.81 atatat struct sysctlnode node;
929 1.81 atatat
930 1.81 atatat node = *rnode;
931 1.81 atatat node.sysctl_data = &t;
932 1.81 atatat t = icmpreturndatabytes;
933 1.81 atatat error = sysctl_lookup(SYSCTLFN_CALL(&node));
934 1.81 atatat if (error || newp == NULL)
935 1.81 atatat return (error);
936 1.81 atatat
937 1.81 atatat if (t < 8 || t > 512)
938 1.81 atatat return (EINVAL);
939 1.81 atatat icmpreturndatabytes = t;
940 1.81 atatat
941 1.81 atatat return (0);
942 1.81 atatat }
943 1.81 atatat
944 1.81 atatat /*
945 1.81 atatat * sysctl helper routine for net.inet.icmp.redirtimeout. ensures that
946 1.81 atatat * the given value is not less than zero and then resets the timeout
947 1.81 atatat * queue.
948 1.81 atatat */
949 1.81 atatat static int
950 1.81 atatat sysctl_net_inet_icmp_redirtimeout(SYSCTLFN_ARGS)
951 1.9 mycroft {
952 1.81 atatat int error, tmp;
953 1.81 atatat struct sysctlnode node;
954 1.9 mycroft
955 1.81 atatat node = *rnode;
956 1.81 atatat node.sysctl_data = &tmp;
957 1.81 atatat tmp = icmp_redirtimeout;
958 1.81 atatat error = sysctl_lookup(SYSCTLFN_CALL(&node));
959 1.81 atatat if (error || newp == NULL)
960 1.81 atatat return (error);
961 1.81 atatat if (tmp < 0)
962 1.81 atatat return (EINVAL);
963 1.81 atatat icmp_redirtimeout = tmp;
964 1.81 atatat
965 1.81 atatat /*
966 1.81 atatat * was it a *defined* side-effect that anyone even *reading*
967 1.81 atatat * this value causes these things to happen?
968 1.81 atatat */
969 1.81 atatat if (icmp_redirect_timeout_q != NULL) {
970 1.81 atatat if (icmp_redirtimeout == 0) {
971 1.81 atatat rt_timer_queue_destroy(icmp_redirect_timeout_q,
972 1.110 thorpej true);
973 1.81 atatat icmp_redirect_timeout_q = NULL;
974 1.81 atatat } else {
975 1.81 atatat rt_timer_queue_change(icmp_redirect_timeout_q,
976 1.81 atatat icmp_redirtimeout);
977 1.63 kml }
978 1.81 atatat } else if (icmp_redirtimeout > 0) {
979 1.81 atatat icmp_redirect_timeout_q =
980 1.81 atatat rt_timer_queue_create(icmp_redirtimeout);
981 1.9 mycroft }
982 1.91 perry
983 1.81 atatat return (0);
984 1.81 atatat }
985 1.81 atatat
986 1.116 thorpej static void
987 1.116 thorpej icmpstat_convert_to_user_cb(void *v1, void *v2, struct cpu_info *ci)
988 1.116 thorpej {
989 1.116 thorpej uint64_t *icpsc = v1;
990 1.116 thorpej uint64_t *icps = v2;
991 1.116 thorpej u_int i;
992 1.116 thorpej
993 1.116 thorpej for (i = 0; i < ICMP_NSTATS; i++)
994 1.116 thorpej icps[i] += icpsc[i];
995 1.116 thorpej }
996 1.116 thorpej
997 1.116 thorpej static void
998 1.116 thorpej icmpstat_convert_to_user(uint64_t *icps)
999 1.116 thorpej {
1000 1.116 thorpej
1001 1.116 thorpej memset(icps, 0, sizeof(uint64_t) * ICMP_NSTATS);
1002 1.116 thorpej percpu_foreach(icmpstat_percpu, icmpstat_convert_to_user_cb, icps);
1003 1.116 thorpej }
1004 1.116 thorpej
1005 1.116 thorpej static int
1006 1.116 thorpej sysctl_net_inet_icmp_stats(SYSCTLFN_ARGS)
1007 1.116 thorpej {
1008 1.116 thorpej struct sysctlnode node;
1009 1.116 thorpej uint64_t icps[ICMP_NSTATS];
1010 1.116 thorpej
1011 1.116 thorpej icmpstat_convert_to_user(icps);
1012 1.116 thorpej node = *rnode;
1013 1.116 thorpej node.sysctl_data = icps;
1014 1.116 thorpej node.sysctl_size = sizeof(icps);
1015 1.116 thorpej return (sysctl_lookup(SYSCTLFN_CALL(&node)));
1016 1.116 thorpej }
1017 1.116 thorpej
1018 1.81 atatat SYSCTL_SETUP(sysctl_net_inet_icmp_setup, "sysctl net.inet.icmp subtree setup")
1019 1.81 atatat {
1020 1.81 atatat
1021 1.82 atatat sysctl_createv(clog, 0, NULL, NULL,
1022 1.82 atatat CTLFLAG_PERMANENT,
1023 1.81 atatat CTLTYPE_NODE, "net", NULL,
1024 1.81 atatat NULL, 0, NULL, 0,
1025 1.81 atatat CTL_NET, CTL_EOL);
1026 1.82 atatat sysctl_createv(clog, 0, NULL, NULL,
1027 1.82 atatat CTLFLAG_PERMANENT,
1028 1.81 atatat CTLTYPE_NODE, "inet", NULL,
1029 1.81 atatat NULL, 0, NULL, 0,
1030 1.81 atatat CTL_NET, PF_INET, CTL_EOL);
1031 1.82 atatat sysctl_createv(clog, 0, NULL, NULL,
1032 1.82 atatat CTLFLAG_PERMANENT,
1033 1.84 atatat CTLTYPE_NODE, "icmp",
1034 1.84 atatat SYSCTL_DESCR("ICMPv4 related settings"),
1035 1.81 atatat NULL, 0, NULL, 0,
1036 1.81 atatat CTL_NET, PF_INET, IPPROTO_ICMP, CTL_EOL);
1037 1.81 atatat
1038 1.82 atatat sysctl_createv(clog, 0, NULL, NULL,
1039 1.82 atatat CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1040 1.84 atatat CTLTYPE_INT, "maskrepl",
1041 1.84 atatat SYSCTL_DESCR("Respond to ICMP_MASKREQ messages"),
1042 1.81 atatat NULL, 0, &icmpmaskrepl, 0,
1043 1.81 atatat CTL_NET, PF_INET, IPPROTO_ICMP,
1044 1.81 atatat ICMPCTL_MASKREPL, CTL_EOL);
1045 1.82 atatat sysctl_createv(clog, 0, NULL, NULL,
1046 1.82 atatat CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1047 1.84 atatat CTLTYPE_INT, "returndatabytes",
1048 1.84 atatat SYSCTL_DESCR("Number of bytes to return in an ICMP "
1049 1.84 atatat "error message"),
1050 1.81 atatat sysctl_net_inet_icmp_returndatabytes, 0,
1051 1.81 atatat &icmpreturndatabytes, 0,
1052 1.81 atatat CTL_NET, PF_INET, IPPROTO_ICMP,
1053 1.81 atatat ICMPCTL_RETURNDATABYTES, CTL_EOL);
1054 1.82 atatat sysctl_createv(clog, 0, NULL, NULL,
1055 1.82 atatat CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1056 1.84 atatat CTLTYPE_INT, "errppslimit",
1057 1.84 atatat SYSCTL_DESCR("Maximum number of outgoing ICMP error "
1058 1.84 atatat "messages per second"),
1059 1.81 atatat NULL, 0, &icmperrppslim, 0,
1060 1.81 atatat CTL_NET, PF_INET, IPPROTO_ICMP,
1061 1.81 atatat ICMPCTL_ERRPPSLIMIT, CTL_EOL);
1062 1.82 atatat sysctl_createv(clog, 0, NULL, NULL,
1063 1.82 atatat CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1064 1.84 atatat CTLTYPE_INT, "rediraccept",
1065 1.84 atatat SYSCTL_DESCR("Accept ICMP_REDIRECT messages"),
1066 1.81 atatat NULL, 0, &icmp_rediraccept, 0,
1067 1.81 atatat CTL_NET, PF_INET, IPPROTO_ICMP,
1068 1.81 atatat ICMPCTL_REDIRACCEPT, CTL_EOL);
1069 1.82 atatat sysctl_createv(clog, 0, NULL, NULL,
1070 1.82 atatat CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1071 1.84 atatat CTLTYPE_INT, "redirtimeout",
1072 1.84 atatat SYSCTL_DESCR("Lifetime of ICMP_REDIRECT generated "
1073 1.84 atatat "routes"),
1074 1.81 atatat sysctl_net_inet_icmp_redirtimeout, 0,
1075 1.81 atatat &icmp_redirtimeout, 0,
1076 1.81 atatat CTL_NET, PF_INET, IPPROTO_ICMP,
1077 1.81 atatat ICMPCTL_REDIRTIMEOUT, CTL_EOL);
1078 1.94 elad sysctl_createv(clog, 0, NULL, NULL,
1079 1.94 elad CTLFLAG_PERMANENT,
1080 1.94 elad CTLTYPE_STRUCT, "stats",
1081 1.94 elad SYSCTL_DESCR("ICMP statistics"),
1082 1.116 thorpej sysctl_net_inet_icmp_stats, 0, NULL, 0,
1083 1.94 elad CTL_NET, PF_INET, IPPROTO_ICMP, ICMPCTL_STATS,
1084 1.94 elad CTL_EOL);
1085 1.24 kml }
1086 1.24 kml
1087 1.116 thorpej void
1088 1.116 thorpej icmp_statinc(u_int stat)
1089 1.116 thorpej {
1090 1.116 thorpej
1091 1.116 thorpej KASSERT(stat < ICMP_NSTATS);
1092 1.116 thorpej ICMP_STATINC(stat);
1093 1.116 thorpej }
1094 1.116 thorpej
1095 1.64 matt /* Table of common MTUs: */
1096 1.64 matt
1097 1.64 matt static const u_int mtu_table[] = {
1098 1.64 matt 65535, 65280, 32000, 17914, 9180, 8166,
1099 1.64 matt 4352, 2002, 1492, 1006, 508, 296, 68, 0
1100 1.64 matt };
1101 1.64 matt
1102 1.55 thorpej void
1103 1.90 perry icmp_mtudisc(struct icmp *icp, struct in_addr faddr)
1104 1.24 kml {
1105 1.57 itojun struct icmp_mtudisc_callback *mc;
1106 1.55 thorpej struct sockaddr *dst = sintosa(&icmpsrc);
1107 1.24 kml struct rtentry *rt;
1108 1.26 kml u_long mtu = ntohs(icp->icmp_nextmtu); /* Why a long? IPv6 */
1109 1.29 kml int error;
1110 1.24 kml
1111 1.24 kml rt = rtalloc1(dst, 1);
1112 1.24 kml if (rt == 0)
1113 1.24 kml return;
1114 1.67 itojun
1115 1.24 kml /* If we didn't get a host route, allocate one */
1116 1.67 itojun
1117 1.24 kml if ((rt->rt_flags & RTF_HOST) == 0) {
1118 1.24 kml struct rtentry *nrt;
1119 1.24 kml
1120 1.67 itojun error = rtrequest((int) RTM_ADD, dst,
1121 1.24 kml (struct sockaddr *) rt->rt_gateway,
1122 1.67 itojun (struct sockaddr *) 0,
1123 1.24 kml RTF_GATEWAY | RTF_HOST | RTF_DYNAMIC, &nrt);
1124 1.24 kml if (error) {
1125 1.24 kml rtfree(rt);
1126 1.24 kml return;
1127 1.24 kml }
1128 1.24 kml nrt->rt_rmx = rt->rt_rmx;
1129 1.24 kml rtfree(rt);
1130 1.24 kml rt = nrt;
1131 1.24 kml }
1132 1.29 kml error = rt_timer_add(rt, icmp_mtudisc_timeout, ip_mtudisc_timeout_q);
1133 1.29 kml if (error) {
1134 1.29 kml rtfree(rt);
1135 1.29 kml return;
1136 1.29 kml }
1137 1.24 kml
1138 1.24 kml if (mtu == 0) {
1139 1.24 kml int i = 0;
1140 1.24 kml
1141 1.70 itojun mtu = ntohs(icp->icmp_ip.ip_len);
1142 1.24 kml /* Some 4.2BSD-based routers incorrectly adjust the ip_len */
1143 1.24 kml if (mtu > rt->rt_rmx.rmx_mtu && rt->rt_rmx.rmx_mtu != 0)
1144 1.24 kml mtu -= (icp->icmp_ip.ip_hl << 2);
1145 1.24 kml
1146 1.26 kml /* If we still can't guess a value, try the route */
1147 1.26 kml
1148 1.26 kml if (mtu == 0) {
1149 1.24 kml mtu = rt->rt_rmx.rmx_mtu;
1150 1.24 kml
1151 1.26 kml /* If no route mtu, default to the interface mtu */
1152 1.26 kml
1153 1.26 kml if (mtu == 0)
1154 1.26 kml mtu = rt->rt_ifp->if_mtu;
1155 1.26 kml }
1156 1.26 kml
1157 1.24 kml for (i = 0; i < sizeof(mtu_table) / sizeof(mtu_table[0]); i++)
1158 1.26 kml if (mtu > mtu_table[i]) {
1159 1.26 kml mtu = mtu_table[i];
1160 1.24 kml break;
1161 1.26 kml }
1162 1.24 kml }
1163 1.24 kml
1164 1.29 kml /*
1165 1.29 kml * XXX: RTV_MTU is overloaded, since the admin can set it
1166 1.29 kml * to turn off PMTU for a route, and the kernel can
1167 1.29 kml * set it to indicate a serious problem with PMTU
1168 1.29 kml * on a route. We should be using a separate flag
1169 1.29 kml * for the kernel to indicate this.
1170 1.29 kml */
1171 1.29 kml
1172 1.24 kml if ((rt->rt_rmx.rmx_locks & RTV_MTU) == 0) {
1173 1.26 kml if (mtu < 296 || mtu > rt->rt_ifp->if_mtu)
1174 1.24 kml rt->rt_rmx.rmx_locks |= RTV_MTU;
1175 1.67 itojun else if (rt->rt_rmx.rmx_mtu > mtu ||
1176 1.56 itojun rt->rt_rmx.rmx_mtu == 0) {
1177 1.116 thorpej ICMP_STATINC(ICMP_STAT_PMTUCHG);
1178 1.24 kml rt->rt_rmx.rmx_mtu = mtu;
1179 1.56 itojun }
1180 1.24 kml }
1181 1.26 kml
1182 1.24 kml if (rt)
1183 1.24 kml rtfree(rt);
1184 1.55 thorpej
1185 1.55 thorpej /*
1186 1.55 thorpej * Notify protocols that the MTU for this destination
1187 1.55 thorpej * has changed.
1188 1.55 thorpej */
1189 1.55 thorpej for (mc = LIST_FIRST(&icmp_mtudisc_callbacks); mc != NULL;
1190 1.55 thorpej mc = LIST_NEXT(mc, mc_list))
1191 1.55 thorpej (*mc->mc_func)(faddr);
1192 1.37 itojun }
1193 1.37 itojun
1194 1.37 itojun /*
1195 1.37 itojun * Return the next larger or smaller MTU plateau (table from RFC 1191)
1196 1.37 itojun * given current value MTU. If DIR is less than zero, a larger plateau
1197 1.37 itojun * is returned; otherwise, a smaller value is returned.
1198 1.37 itojun */
1199 1.98 matt u_int
1200 1.98 matt ip_next_mtu(u_int mtu, int dir) /* XXX */
1201 1.37 itojun {
1202 1.37 itojun int i;
1203 1.37 itojun
1204 1.64 matt for (i = 0; i < (sizeof mtu_table) / (sizeof mtu_table[0]); i++) {
1205 1.64 matt if (mtu >= mtu_table[i])
1206 1.37 itojun break;
1207 1.37 itojun }
1208 1.37 itojun
1209 1.37 itojun if (dir < 0) {
1210 1.37 itojun if (i == 0) {
1211 1.37 itojun return 0;
1212 1.37 itojun } else {
1213 1.64 matt return mtu_table[i - 1];
1214 1.37 itojun }
1215 1.37 itojun } else {
1216 1.64 matt if (mtu_table[i] == 0) {
1217 1.37 itojun return 0;
1218 1.64 matt } else if (mtu > mtu_table[i]) {
1219 1.64 matt return mtu_table[i];
1220 1.37 itojun } else {
1221 1.64 matt return mtu_table[i + 1];
1222 1.37 itojun }
1223 1.37 itojun }
1224 1.29 kml }
1225 1.29 kml
1226 1.29 kml static void
1227 1.105 christos icmp_mtudisc_timeout(struct rtentry *rt, struct rttimer *r)
1228 1.29 kml {
1229 1.29 kml if (rt == NULL)
1230 1.29 kml panic("icmp_mtudisc_timeout: bad route to timeout");
1231 1.67 itojun if ((rt->rt_flags & (RTF_DYNAMIC | RTF_HOST)) ==
1232 1.29 kml (RTF_DYNAMIC | RTF_HOST)) {
1233 1.112 dyoung rtrequest((int) RTM_DELETE, rt_getkey(rt),
1234 1.29 kml rt->rt_gateway, rt_mask(rt), rt->rt_flags, 0);
1235 1.29 kml } else {
1236 1.29 kml if ((rt->rt_rmx.rmx_locks & RTV_MTU) == 0) {
1237 1.29 kml rt->rt_rmx.rmx_mtu = 0;
1238 1.29 kml }
1239 1.63 kml }
1240 1.63 kml }
1241 1.63 kml
1242 1.63 kml static void
1243 1.105 christos icmp_redirect_timeout(struct rtentry *rt, struct rttimer *r)
1244 1.63 kml {
1245 1.63 kml if (rt == NULL)
1246 1.63 kml panic("icmp_redirect_timeout: bad route to timeout");
1247 1.67 itojun if ((rt->rt_flags & (RTF_DYNAMIC | RTF_HOST)) ==
1248 1.63 kml (RTF_DYNAMIC | RTF_HOST)) {
1249 1.112 dyoung rtrequest((int) RTM_DELETE, rt_getkey(rt),
1250 1.63 kml rt->rt_gateway, rt_mask(rt), rt->rt_flags, 0);
1251 1.29 kml }
1252 1.40 thorpej }
1253 1.40 thorpej
1254 1.40 thorpej /*
1255 1.40 thorpej * Perform rate limit check.
1256 1.40 thorpej * Returns 0 if it is okay to send the icmp packet.
1257 1.40 thorpej * Returns 1 if the router SHOULD NOT send this icmp packet due to rate
1258 1.40 thorpej * limitation.
1259 1.40 thorpej *
1260 1.40 thorpej * XXX per-destination/type check necessary?
1261 1.40 thorpej */
1262 1.40 thorpej static int
1263 1.105 christos icmp_ratelimit(const struct in_addr *dst, const int type,
1264 1.105 christos const int code)
1265 1.40 thorpej {
1266 1.40 thorpej
1267 1.51 itojun /* PPS limit */
1268 1.51 itojun if (!ppsratecheck(&icmperrppslim_last, &icmperrpps_count,
1269 1.51 itojun icmperrppslim)) {
1270 1.51 itojun /* The packet is subject to rate limit */
1271 1.51 itojun return 1;
1272 1.51 itojun }
1273 1.51 itojun
1274 1.90 perry /* okay to send */
1275 1.51 itojun return 0;
1276 1.1 cgd }
1277