1 /*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 1982, 1986, 1988, 1993
5 * The Regents of the University of California. 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 University 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 REGENTS 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 REGENTS 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 #include <sys/cdefs.h>
33 #include "opt_inet.h"
34
35 #include <sys/param.h>
36 #include <sys/systm.h>
37 #include <sys/mbuf.h>
38 #include <sys/protosw.h>
39 #include <sys/socket.h>
40 #include <sys/time.h>
41 #include <sys/kernel.h>
42 #include <sys/lock.h>
43 #include <sys/sysctl.h>
44 #include <sys/syslog.h>
45
46 #include <net/if.h>
47 #include <net/if_var.h>
48 #include <net/if_private.h>
49 #include <net/if_types.h>
50 #include <net/route.h>
51 #include <net/route/route_ctl.h>
52 #include <net/route/nhop.h>
53 #include <net/vnet.h>
54
55 #include <netinet/in.h>
56 #include <netinet/in_fib.h>
57 #include <netinet/in_pcb.h>
58 #include <netinet/in_systm.h>
59 #include <netinet/in_var.h>
60 #include <netinet/ip.h>
61 #include <netinet/ip_icmp.h>
62 #include <netinet/ip_var.h>
63 #include <netinet/ip_options.h>
64 #include <netinet/sctp.h>
65 #include <netinet/tcp.h>
66 #include <netinet/tcpip.h>
67 #include <netinet/icmp_var.h>
68
69 #ifdef INET
70
71 #include <machine/in_cksum.h>
72
73 #include <security/mac/mac_framework.h>
74 #endif /* INET */
75
76 extern ipproto_ctlinput_t *ip_ctlprotox[];
77
78 /*
79 * ICMP routines: error generation, receive packet processing, and
80 * routines to turnaround packets back to the originator, and
81 * host table maintenance routines.
82 */
83 static int sysctl_icmplim_and_jitter(SYSCTL_HANDLER_ARGS);
84 VNET_DEFINE_STATIC(u_int, icmplim) = 200;
85 #define V_icmplim VNET(icmplim)
86 SYSCTL_PROC(_net_inet_icmp, ICMPCTL_ICMPLIM, icmplim, CTLTYPE_UINT |
87 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(icmplim), 0,
88 &sysctl_icmplim_and_jitter, "IU",
89 "Maximum number of ICMP responses per second");
90
91 VNET_DEFINE_STATIC(int, icmplim_curr_jitter) = 0;
92 #define V_icmplim_curr_jitter VNET(icmplim_curr_jitter)
93 VNET_DEFINE_STATIC(u_int, icmplim_jitter) = 16;
94 #define V_icmplim_jitter VNET(icmplim_jitter)
95 SYSCTL_PROC(_net_inet_icmp, OID_AUTO, icmplim_jitter, CTLTYPE_UINT |
96 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(icmplim_jitter), 0,
97 &sysctl_icmplim_and_jitter, "IU",
98 "Random icmplim jitter adjustment limit");
99
100 VNET_DEFINE_STATIC(int, icmplim_output) = 1;
101 #define V_icmplim_output VNET(icmplim_output)
102 SYSCTL_INT(_net_inet_icmp, OID_AUTO, icmplim_output, CTLFLAG_VNET | CTLFLAG_RW,
103 &VNET_NAME(icmplim_output), 0,
104 "Enable logging of ICMP response rate limiting");
105
106 #ifdef INET
107 VNET_PCPUSTAT_DEFINE(struct icmpstat, icmpstat);
108 VNET_PCPUSTAT_SYSINIT(icmpstat);
109 SYSCTL_VNET_PCPUSTAT(_net_inet_icmp, ICMPCTL_STATS, stats, struct icmpstat,
110 icmpstat, "ICMP statistics (struct icmpstat, netinet/icmp_var.h)");
111
112 #ifdef VIMAGE
113 VNET_PCPUSTAT_SYSUNINIT(icmpstat);
114 #endif /* VIMAGE */
115
116 VNET_DEFINE_STATIC(int, icmpmaskrepl) = 0;
117 #define V_icmpmaskrepl VNET(icmpmaskrepl)
118 SYSCTL_INT(_net_inet_icmp, ICMPCTL_MASKREPL, maskrepl, CTLFLAG_VNET | CTLFLAG_RW,
119 &VNET_NAME(icmpmaskrepl), 0,
120 "Reply to ICMP Address Mask Request packets");
121
122 VNET_DEFINE_STATIC(u_int, icmpmaskfake) = 0;
123 #define V_icmpmaskfake VNET(icmpmaskfake)
124 SYSCTL_UINT(_net_inet_icmp, OID_AUTO, maskfake, CTLFLAG_VNET | CTLFLAG_RW,
125 &VNET_NAME(icmpmaskfake), 0,
126 "Fake reply to ICMP Address Mask Request packets");
127
128 VNET_DEFINE(int, drop_redirect) = 0;
129 #define V_drop_redirect VNET(drop_redirect)
130 SYSCTL_INT(_net_inet_icmp, OID_AUTO, drop_redirect, CTLFLAG_VNET | CTLFLAG_RW,
131 &VNET_NAME(drop_redirect), 0,
132 "Ignore ICMP redirects");
133
134 VNET_DEFINE_STATIC(int, log_redirect) = 0;
135 #define V_log_redirect VNET(log_redirect)
136 SYSCTL_INT(_net_inet_icmp, OID_AUTO, log_redirect, CTLFLAG_VNET | CTLFLAG_RW,
137 &VNET_NAME(log_redirect), 0,
138 "Log ICMP redirects to the console");
139
140 VNET_DEFINE_STATIC(int, redirtimeout) = 60 * 10; /* 10 minutes */
141 #define V_redirtimeout VNET(redirtimeout)
142 SYSCTL_INT(_net_inet_icmp, OID_AUTO, redirtimeout, CTLFLAG_VNET | CTLFLAG_RW,
143 &VNET_NAME(redirtimeout), 0,
144 "Delay in seconds before expiring redirect route");
145
146 VNET_DEFINE_STATIC(char, reply_src[IFNAMSIZ]);
147 #define V_reply_src VNET(reply_src)
148 SYSCTL_STRING(_net_inet_icmp, OID_AUTO, reply_src, CTLFLAG_VNET | CTLFLAG_RW,
149 &VNET_NAME(reply_src), IFNAMSIZ,
150 "ICMP reply source for non-local packets");
151
152 VNET_DEFINE_STATIC(int, icmp_rfi) = 0;
153 #define V_icmp_rfi VNET(icmp_rfi)
154 SYSCTL_INT(_net_inet_icmp, OID_AUTO, reply_from_interface, CTLFLAG_VNET | CTLFLAG_RW,
155 &VNET_NAME(icmp_rfi), 0,
156 "ICMP reply from incoming interface for non-local packets");
157 /* Router requirements RFC 1812 section 4.3.2.3 requires 576 - 28. */
158 VNET_DEFINE_STATIC(int, icmp_quotelen) = 548;
159 #define V_icmp_quotelen VNET(icmp_quotelen)
160 SYSCTL_INT(_net_inet_icmp, OID_AUTO, quotelen, CTLFLAG_VNET | CTLFLAG_RW,
161 &VNET_NAME(icmp_quotelen), 0,
162 "Number of bytes from original packet to quote in ICMP reply");
163
164 VNET_DEFINE_STATIC(int, icmpbmcastecho) = 0;
165 #define V_icmpbmcastecho VNET(icmpbmcastecho)
166 SYSCTL_INT(_net_inet_icmp, OID_AUTO, bmcastecho, CTLFLAG_VNET | CTLFLAG_RW,
167 &VNET_NAME(icmpbmcastecho), 0,
168 "Reply to multicast ICMP Echo Request and Timestamp packets");
169
170 VNET_DEFINE_STATIC(int, icmptstamprepl) = 1;
171 #define V_icmptstamprepl VNET(icmptstamprepl)
172 SYSCTL_INT(_net_inet_icmp, OID_AUTO, tstamprepl, CTLFLAG_VNET | CTLFLAG_RW,
173 &VNET_NAME(icmptstamprepl), 0,
174 "Respond to ICMP Timestamp packets");
175
176 VNET_DEFINE_STATIC(int, error_keeptags) = 0;
177 #define V_error_keeptags VNET(error_keeptags)
178 SYSCTL_INT(_net_inet_icmp, OID_AUTO, error_keeptags, CTLFLAG_VNET | CTLFLAG_RW,
179 &VNET_NAME(error_keeptags), 0,
180 "ICMP error response keeps copy of mbuf_tags of original packet");
181
182 #ifdef ICMPPRINTFS
183 int icmpprintfs = 0;
184 #endif
185
186 static void icmp_reflect(struct mbuf *);
187 static void icmp_send(struct mbuf *, struct mbuf *);
188 static int icmp_verify_redirect_gateway(struct sockaddr_in *,
189 struct sockaddr_in *, struct sockaddr_in *, u_int);
190
191 /*
192 * Kernel module interface for updating icmpstat. The argument is an index
193 * into icmpstat treated as an array of u_long. While this encodes the
194 * general layout of icmpstat into the caller, it doesn't encode its
195 * location, so that future changes to add, for example, per-CPU stats
196 * support won't cause binary compatibility problems for kernel modules.
197 */
198 void
kmod_icmpstat_inc(int statnum)199 kmod_icmpstat_inc(int statnum)
200 {
201
202 counter_u64_add(VNET(icmpstat)[statnum], 1);
203 }
204
205 /*
206 * Generate an error packet of type error
207 * in response to bad packet ip.
208 */
209 void
icmp_error(struct mbuf * n,int type,int code,uint32_t dest,int mtu)210 icmp_error(struct mbuf *n, int type, int code, uint32_t dest, int mtu)
211 {
212 struct ip *oip, *nip;
213 struct icmp *icp;
214 struct mbuf *m;
215 unsigned icmplen, icmpelen, nlen, oiphlen;
216
217 KASSERT((u_int)type <= ICMP_MAXTYPE, ("%s: illegal ICMP type",
218 __func__));
219
220 if (type != ICMP_REDIRECT)
221 ICMPSTAT_INC(icps_error);
222 /*
223 * Don't send error:
224 * if the original packet was encrypted.
225 * if not the first fragment of message.
226 * in response to a multicast or broadcast packet.
227 * if the old packet protocol was an ICMP error message.
228 */
229 if (n->m_flags & M_DECRYPTED)
230 goto freeit;
231 if (n->m_flags & (M_BCAST|M_MCAST))
232 goto freeit;
233
234 /* Drop if IP header plus 8 bytes is not contiguous in first mbuf. */
235 if (n->m_len < sizeof(struct ip) + ICMP_MINLEN)
236 goto freeit;
237 oip = mtod(n, struct ip *);
238 oiphlen = oip->ip_hl << 2;
239 if (n->m_len < oiphlen + ICMP_MINLEN)
240 goto freeit;
241 #ifdef ICMPPRINTFS
242 if (icmpprintfs)
243 printf("icmp_error(%p, %x, %d)\n", oip, type, code);
244 #endif
245 if (oip->ip_off & htons(~(IP_MF|IP_DF)))
246 goto freeit;
247 if (oip->ip_p == IPPROTO_ICMP && type != ICMP_REDIRECT &&
248 !ICMP_INFOTYPE(((struct icmp *)((caddr_t)oip +
249 oiphlen))->icmp_type)) {
250 ICMPSTAT_INC(icps_oldicmp);
251 goto freeit;
252 }
253 /*
254 * Calculate length to quote from original packet and
255 * prevent the ICMP mbuf from overflowing.
256 * Unfortunately this is non-trivial since ip_forward()
257 * sends us truncated packets.
258 */
259 nlen = m_length(n, NULL);
260 if (oip->ip_p == IPPROTO_TCP) {
261 struct tcphdr *th;
262 int tcphlen;
263
264 if (oiphlen + sizeof(struct tcphdr) > n->m_len &&
265 n->m_next == NULL)
266 goto stdreply;
267 if (n->m_len < oiphlen + sizeof(struct tcphdr) &&
268 (n = m_pullup(n, oiphlen + sizeof(struct tcphdr))) == NULL)
269 goto freeit;
270 oip = mtod(n, struct ip *);
271 th = mtodo(n, oiphlen);
272 tcphlen = th->th_off << 2;
273 if (tcphlen < sizeof(struct tcphdr))
274 goto freeit;
275 if (ntohs(oip->ip_len) < oiphlen + tcphlen)
276 goto freeit;
277 if (oiphlen + tcphlen > n->m_len && n->m_next == NULL)
278 goto stdreply;
279 if (n->m_len < oiphlen + tcphlen &&
280 (n = m_pullup(n, oiphlen + tcphlen)) == NULL)
281 goto freeit;
282 oip = mtod(n, struct ip *);
283 icmpelen = max(tcphlen, min(V_icmp_quotelen,
284 ntohs(oip->ip_len) - oiphlen));
285 } else if (oip->ip_p == IPPROTO_SCTP) {
286 struct sctphdr *sh;
287 struct sctp_chunkhdr *ch;
288
289 if (ntohs(oip->ip_len) < oiphlen + sizeof(struct sctphdr))
290 goto stdreply;
291 if (oiphlen + sizeof(struct sctphdr) > n->m_len &&
292 n->m_next == NULL)
293 goto stdreply;
294 if (n->m_len < oiphlen + sizeof(struct sctphdr) &&
295 (n = m_pullup(n, oiphlen + sizeof(struct sctphdr))) == NULL)
296 goto freeit;
297 oip = mtod(n, struct ip *);
298 icmpelen = max(sizeof(struct sctphdr),
299 min(V_icmp_quotelen, ntohs(oip->ip_len) - oiphlen));
300 sh = mtodo(n, oiphlen);
301 if (ntohl(sh->v_tag) == 0 &&
302 ntohs(oip->ip_len) >= oiphlen +
303 sizeof(struct sctphdr) + 8 &&
304 (n->m_len >= oiphlen + sizeof(struct sctphdr) + 8 ||
305 n->m_next != NULL)) {
306 if (n->m_len < oiphlen + sizeof(struct sctphdr) + 8 &&
307 (n = m_pullup(n, oiphlen +
308 sizeof(struct sctphdr) + 8)) == NULL)
309 goto freeit;
310 oip = mtod(n, struct ip *);
311 sh = mtodo(n, oiphlen);
312 ch = (struct sctp_chunkhdr *)(sh + 1);
313 if (ch->chunk_type == SCTP_INITIATION) {
314 icmpelen = max(sizeof(struct sctphdr) + 8,
315 min(V_icmp_quotelen, ntohs(oip->ip_len) -
316 oiphlen));
317 }
318 }
319 } else
320 stdreply: icmpelen = max(8, min(V_icmp_quotelen, ntohs(oip->ip_len) -
321 oiphlen));
322
323 icmplen = min(oiphlen + icmpelen, nlen);
324 if (icmplen < sizeof(struct ip))
325 goto freeit;
326
327 if (MHLEN > sizeof(struct ip) + ICMP_MINLEN + icmplen)
328 m = m_gethdr(M_NOWAIT, MT_DATA);
329 else
330 m = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR);
331 if (m == NULL)
332 goto freeit;
333 #ifdef MAC
334 mac_netinet_icmp_reply(n, m);
335 #endif
336 icmplen = min(icmplen, M_TRAILINGSPACE(m) -
337 sizeof(struct ip) - ICMP_MINLEN);
338 m_align(m, sizeof(struct ip) + ICMP_MINLEN + icmplen);
339 m->m_data += sizeof(struct ip);
340 m->m_len = ICMP_MINLEN + icmplen;
341
342 /* XXX MRT make the outgoing packet use the same FIB
343 * that was associated with the incoming packet
344 */
345 M_SETFIB(m, M_GETFIB(n));
346 icp = mtod(m, struct icmp *);
347 ICMPSTAT_INC2(icps_outhist, type);
348 icp->icmp_type = type;
349 if (type == ICMP_REDIRECT)
350 icp->icmp_gwaddr.s_addr = dest;
351 else {
352 icp->icmp_void = 0;
353 /*
354 * The following assignments assume an overlay with the
355 * just zeroed icmp_void field.
356 */
357 if (type == ICMP_PARAMPROB) {
358 icp->icmp_pptr = code;
359 code = 0;
360 } else if (type == ICMP_UNREACH &&
361 code == ICMP_UNREACH_NEEDFRAG && mtu) {
362 icp->icmp_nextmtu = htons(mtu);
363 }
364 }
365 icp->icmp_code = code;
366
367 /*
368 * Copy the quotation into ICMP message and
369 * convert quoted IP header back to network representation.
370 */
371 m_copydata(n, 0, icmplen, (caddr_t)&icp->icmp_ip);
372 nip = &icp->icmp_ip;
373
374 /*
375 * Set up ICMP message mbuf and copy old IP header (without options
376 * in front of ICMP message.
377 * If the original mbuf was meant to bypass the firewall, the error
378 * reply should bypass as well.
379 */
380 m->m_flags |= n->m_flags & M_SKIP_FIREWALL;
381 KASSERT(M_LEADINGSPACE(m) >= sizeof(struct ip),
382 ("insufficient space for ip header"));
383 m->m_data -= sizeof(struct ip);
384 m->m_len += sizeof(struct ip);
385 m->m_pkthdr.len = m->m_len;
386 m->m_pkthdr.rcvif = n->m_pkthdr.rcvif;
387 nip = mtod(m, struct ip *);
388 bcopy((caddr_t)oip, (caddr_t)nip, sizeof(struct ip));
389 nip->ip_len = htons(m->m_len);
390 nip->ip_v = IPVERSION;
391 nip->ip_hl = 5;
392 nip->ip_p = IPPROTO_ICMP;
393 nip->ip_tos = 0;
394 nip->ip_off = 0;
395
396 if (V_error_keeptags)
397 m_tag_copy_chain(m, n, M_NOWAIT);
398
399 icmp_reflect(m);
400
401 freeit:
402 m_freem(n);
403 }
404
405 int
icmp_errmap(const struct icmp * icp)406 icmp_errmap(const struct icmp *icp)
407 {
408
409 switch (icp->icmp_type) {
410 case ICMP_UNREACH:
411 switch (icp->icmp_code) {
412 case ICMP_UNREACH_NET:
413 case ICMP_UNREACH_HOST:
414 case ICMP_UNREACH_SRCFAIL:
415 case ICMP_UNREACH_NET_UNKNOWN:
416 case ICMP_UNREACH_HOST_UNKNOWN:
417 case ICMP_UNREACH_ISOLATED:
418 case ICMP_UNREACH_TOSNET:
419 case ICMP_UNREACH_TOSHOST:
420 case ICMP_UNREACH_HOST_PRECEDENCE:
421 case ICMP_UNREACH_PRECEDENCE_CUTOFF:
422 return (EHOSTUNREACH);
423 case ICMP_UNREACH_NEEDFRAG:
424 return (EMSGSIZE);
425 case ICMP_UNREACH_PROTOCOL:
426 case ICMP_UNREACH_PORT:
427 case ICMP_UNREACH_NET_PROHIB:
428 case ICMP_UNREACH_HOST_PROHIB:
429 case ICMP_UNREACH_FILTER_PROHIB:
430 return (ECONNREFUSED);
431 default:
432 return (0);
433 }
434 case ICMP_TIMXCEED:
435 switch (icp->icmp_code) {
436 case ICMP_TIMXCEED_INTRANS:
437 return (EHOSTUNREACH);
438 default:
439 return (0);
440 }
441 case ICMP_PARAMPROB:
442 switch (icp->icmp_code) {
443 case ICMP_PARAMPROB_ERRATPTR:
444 case ICMP_PARAMPROB_OPTABSENT:
445 return (ENOPROTOOPT);
446 default:
447 return (0);
448 }
449 default:
450 return (0);
451 }
452 }
453
454 /*
455 * Process a received ICMP message.
456 */
457 int
icmp_input(struct mbuf ** mp,int * offp,int proto)458 icmp_input(struct mbuf **mp, int *offp, int proto)
459 {
460 struct icmp *icp;
461 struct in_ifaddr *ia;
462 struct mbuf *m = *mp;
463 struct ip *ip = mtod(m, struct ip *);
464 struct sockaddr_in icmpsrc, icmpdst, icmpgw;
465 int hlen = *offp;
466 int icmplen = ntohs(ip->ip_len) - *offp;
467 int i, code;
468 int fibnum;
469
470 NET_EPOCH_ASSERT();
471
472 *mp = NULL;
473
474 /*
475 * Locate icmp structure in mbuf, and check
476 * that not corrupted and of at least minimum length.
477 */
478 #ifdef ICMPPRINTFS
479 if (icmpprintfs) {
480 char srcbuf[INET_ADDRSTRLEN];
481 char dstbuf[INET_ADDRSTRLEN];
482
483 printf("icmp_input from %s to %s, len %d\n",
484 inet_ntoa_r(ip->ip_src, srcbuf),
485 inet_ntoa_r(ip->ip_dst, dstbuf), icmplen);
486 }
487 #endif
488 if (icmplen < ICMP_MINLEN) {
489 ICMPSTAT_INC(icps_tooshort);
490 goto freeit;
491 }
492 i = hlen + min(icmplen, ICMP_ADVLENMIN);
493 if (m->m_len < i && (m = m_pullup(m, i)) == NULL) {
494 ICMPSTAT_INC(icps_tooshort);
495 return (IPPROTO_DONE);
496 }
497 ip = mtod(m, struct ip *);
498 m->m_len -= hlen;
499 m->m_data += hlen;
500 icp = mtod(m, struct icmp *);
501 if (in_cksum(m, icmplen)) {
502 ICMPSTAT_INC(icps_checksum);
503 goto freeit;
504 }
505 m->m_len += hlen;
506 m->m_data -= hlen;
507
508 #ifdef ICMPPRINTFS
509 if (icmpprintfs)
510 printf("icmp_input, type %d code %d\n", icp->icmp_type,
511 icp->icmp_code);
512 #endif
513
514 /*
515 * Message type specific processing.
516 */
517 if (icp->icmp_type > ICMP_MAXTYPE)
518 goto raw;
519
520 /* Initialize */
521 bzero(&icmpsrc, sizeof(icmpsrc));
522 icmpsrc.sin_len = sizeof(struct sockaddr_in);
523 icmpsrc.sin_family = AF_INET;
524 bzero(&icmpdst, sizeof(icmpdst));
525 icmpdst.sin_len = sizeof(struct sockaddr_in);
526 icmpdst.sin_family = AF_INET;
527 bzero(&icmpgw, sizeof(icmpgw));
528 icmpgw.sin_len = sizeof(struct sockaddr_in);
529 icmpgw.sin_family = AF_INET;
530
531 ICMPSTAT_INC2(icps_inhist, icp->icmp_type);
532 code = icp->icmp_code;
533 switch (icp->icmp_type) {
534 case ICMP_UNREACH:
535 if (code > ICMP_UNREACH_PRECEDENCE_CUTOFF)
536 goto badcode;
537 else
538 goto deliver;
539
540 case ICMP_TIMXCEED:
541 if (code > ICMP_TIMXCEED_REASS)
542 goto badcode;
543 else
544 goto deliver;
545
546 case ICMP_PARAMPROB:
547 if (code > ICMP_PARAMPROB_LENGTH)
548 goto badcode;
549
550 deliver:
551 /*
552 * Problem with datagram; advise higher level routines.
553 */
554 if (icmplen < ICMP_ADVLENMIN || icmplen < ICMP_ADVLEN(icp) ||
555 icp->icmp_ip.ip_hl < (sizeof(struct ip) >> 2)) {
556 ICMPSTAT_INC(icps_badlen);
557 goto freeit;
558 }
559 /* Discard ICMP's in response to multicast packets */
560 if (IN_MULTICAST(ntohl(icp->icmp_ip.ip_dst.s_addr)))
561 goto badcode;
562 /* Filter out responses to INADDR_ANY, protocols ignore it. */
563 if (icp->icmp_ip.ip_dst.s_addr == INADDR_ANY ||
564 icp->icmp_ip.ip_src.s_addr == INADDR_ANY)
565 goto freeit;
566 #ifdef ICMPPRINTFS
567 if (icmpprintfs)
568 printf("deliver to protocol %d\n", icp->icmp_ip.ip_p);
569 #endif
570 /*
571 * XXX if the packet contains [IPv4 AH TCP], we can't make a
572 * notification to TCP layer.
573 */
574 i = sizeof(struct ip) + min(icmplen, ICMP_ADVLENPREF(icp));
575 ip_stripoptions(m);
576 if (m->m_len < i && (m = m_pullup(m, i)) == NULL) {
577 /* This should actually not happen */
578 ICMPSTAT_INC(icps_tooshort);
579 return (IPPROTO_DONE);
580 }
581 ip = mtod(m, struct ip *);
582 icp = (struct icmp *)(ip + 1);
583 /*
584 * The upper layer handler can rely on:
585 * - The outer IP header has no options.
586 * - The outer IP header, the ICMP header, the inner IP header,
587 * and the first n bytes of the inner payload are contiguous.
588 * n is at least 8, but might be larger based on
589 * ICMP_ADVLENPREF. See its definition in ip_icmp.h.
590 */
591 if (ip_ctlprotox[icp->icmp_ip.ip_p] != NULL)
592 ip_ctlprotox[icp->icmp_ip.ip_p](icp);
593 break;
594
595 badcode:
596 ICMPSTAT_INC(icps_badcode);
597 break;
598
599 case ICMP_ECHO:
600 if (!V_icmpbmcastecho
601 && (m->m_flags & (M_MCAST | M_BCAST)) != 0) {
602 ICMPSTAT_INC(icps_bmcastecho);
603 break;
604 }
605 if (badport_bandlim(BANDLIM_ICMP_ECHO) < 0)
606 goto freeit;
607 icp->icmp_type = ICMP_ECHOREPLY;
608 goto reflect;
609
610 case ICMP_TSTAMP:
611 if (V_icmptstamprepl == 0)
612 break;
613 if (!V_icmpbmcastecho
614 && (m->m_flags & (M_MCAST | M_BCAST)) != 0) {
615 ICMPSTAT_INC(icps_bmcasttstamp);
616 break;
617 }
618 if (icmplen < ICMP_TSLEN) {
619 ICMPSTAT_INC(icps_badlen);
620 break;
621 }
622 if (badport_bandlim(BANDLIM_ICMP_TSTAMP) < 0)
623 goto freeit;
624 icp->icmp_type = ICMP_TSTAMPREPLY;
625 icp->icmp_rtime = iptime();
626 icp->icmp_ttime = icp->icmp_rtime; /* bogus, do later! */
627 goto reflect;
628
629 case ICMP_MASKREQ:
630 if (V_icmpmaskrepl == 0)
631 break;
632 /*
633 * We are not able to respond with all ones broadcast
634 * unless we receive it over a point-to-point interface.
635 */
636 if (icmplen < ICMP_MASKLEN)
637 break;
638 switch (ip->ip_dst.s_addr) {
639 case INADDR_BROADCAST:
640 case INADDR_ANY:
641 icmpdst.sin_addr = ip->ip_src;
642 break;
643
644 default:
645 icmpdst.sin_addr = ip->ip_dst;
646 }
647 ia = (struct in_ifaddr *)ifaof_ifpforaddr(
648 (struct sockaddr *)&icmpdst, m->m_pkthdr.rcvif);
649 if (ia == NULL)
650 break;
651 if (ia->ia_ifp == NULL)
652 break;
653 icp->icmp_type = ICMP_MASKREPLY;
654 if (V_icmpmaskfake == 0)
655 icp->icmp_mask = ia->ia_sockmask.sin_addr.s_addr;
656 else
657 icp->icmp_mask = V_icmpmaskfake;
658 if (ip->ip_src.s_addr == 0) {
659 if (ia->ia_ifp->if_flags & IFF_BROADCAST)
660 ip->ip_src = satosin(&ia->ia_broadaddr)->sin_addr;
661 else if (ia->ia_ifp->if_flags & IFF_POINTOPOINT)
662 ip->ip_src = satosin(&ia->ia_dstaddr)->sin_addr;
663 }
664 reflect:
665 ICMPSTAT_INC(icps_reflect);
666 ICMPSTAT_INC2(icps_outhist, icp->icmp_type);
667 icmp_reflect(m);
668 return (IPPROTO_DONE);
669
670 case ICMP_REDIRECT:
671 if (V_log_redirect) {
672 u_long src, dst, gw;
673
674 src = ntohl(ip->ip_src.s_addr);
675 dst = ntohl(icp->icmp_ip.ip_dst.s_addr);
676 gw = ntohl(icp->icmp_gwaddr.s_addr);
677 printf("icmp redirect from %d.%d.%d.%d: "
678 "%d.%d.%d.%d => %d.%d.%d.%d\n",
679 (int)(src >> 24), (int)((src >> 16) & 0xff),
680 (int)((src >> 8) & 0xff), (int)(src & 0xff),
681 (int)(dst >> 24), (int)((dst >> 16) & 0xff),
682 (int)((dst >> 8) & 0xff), (int)(dst & 0xff),
683 (int)(gw >> 24), (int)((gw >> 16) & 0xff),
684 (int)((gw >> 8) & 0xff), (int)(gw & 0xff));
685 }
686 /*
687 * RFC1812 says we must ignore ICMP redirects if we
688 * are acting as router.
689 */
690 if (V_drop_redirect || V_ipforwarding)
691 break;
692 if (code > 3)
693 goto badcode;
694 if (icmplen < ICMP_ADVLENMIN || icmplen < ICMP_ADVLEN(icp) ||
695 icp->icmp_ip.ip_hl < (sizeof(struct ip) >> 2)) {
696 ICMPSTAT_INC(icps_badlen);
697 break;
698 }
699 /*
700 * Short circuit routing redirects to force
701 * immediate change in the kernel's routing
702 * tables. The message is also handed to anyone
703 * listening on a raw socket (e.g. the routing
704 * daemon for use in updating its tables).
705 */
706 icmpgw.sin_addr = ip->ip_src;
707 icmpdst.sin_addr = icp->icmp_gwaddr;
708 #ifdef ICMPPRINTFS
709 if (icmpprintfs) {
710 char dstbuf[INET_ADDRSTRLEN];
711 char gwbuf[INET_ADDRSTRLEN];
712
713 printf("redirect dst %s to %s\n",
714 inet_ntoa_r(icp->icmp_ip.ip_dst, dstbuf),
715 inet_ntoa_r(icp->icmp_gwaddr, gwbuf));
716 }
717 #endif
718 icmpsrc.sin_addr = icp->icmp_ip.ip_dst;
719
720 /*
721 * RFC 1122 says network (code 0,2) redirects SHOULD
722 * be treated identically to the host redirects.
723 * Given that, ignore network masks.
724 */
725
726 /*
727 * Variable values:
728 * icmpsrc: route destination
729 * icmpdst: route gateway
730 * icmpgw: message source
731 */
732
733 if (icmp_verify_redirect_gateway(&icmpgw, &icmpsrc, &icmpdst,
734 M_GETFIB(m)) != 0) {
735 /* TODO: increment bad redirects here */
736 break;
737 }
738
739 for ( fibnum = 0; fibnum < rt_numfibs; fibnum++) {
740 rib_add_redirect(fibnum, (struct sockaddr *)&icmpsrc,
741 (struct sockaddr *)&icmpdst,
742 (struct sockaddr *)&icmpgw, m->m_pkthdr.rcvif,
743 RTF_GATEWAY, V_redirtimeout);
744 }
745 break;
746
747 /*
748 * No kernel processing for the following;
749 * just fall through to send to raw listener.
750 */
751 case ICMP_ECHOREPLY:
752 case ICMP_ROUTERADVERT:
753 case ICMP_ROUTERSOLICIT:
754 case ICMP_TSTAMPREPLY:
755 case ICMP_IREQREPLY:
756 case ICMP_MASKREPLY:
757 case ICMP_SOURCEQUENCH:
758 default:
759 break;
760 }
761
762 raw:
763 *mp = m;
764 rip_input(mp, offp, proto);
765 return (IPPROTO_DONE);
766
767 freeit:
768 m_freem(m);
769 return (IPPROTO_DONE);
770 }
771
772 /*
773 * Reflect the ip packet back to the source
774 */
775 static void
icmp_reflect(struct mbuf * m)776 icmp_reflect(struct mbuf *m)
777 {
778 struct ip *ip = mtod(m, struct ip *);
779 struct ifaddr *ifa;
780 struct ifnet *ifp;
781 struct in_ifaddr *ia;
782 struct in_addr t;
783 struct nhop_object *nh;
784 struct mbuf *opts = NULL;
785 int optlen = (ip->ip_hl << 2) - sizeof(struct ip);
786
787 NET_EPOCH_ASSERT();
788
789 if (IN_MULTICAST(ntohl(ip->ip_src.s_addr)) ||
790 (IN_EXPERIMENTAL(ntohl(ip->ip_src.s_addr)) && !V_ip_allow_net240) ||
791 (IN_ZERONET(ntohl(ip->ip_src.s_addr)) && !V_ip_allow_net0) ) {
792 m_freem(m); /* Bad return address */
793 ICMPSTAT_INC(icps_badaddr);
794 goto done; /* Ip_output() will check for broadcast */
795 }
796
797 t = ip->ip_dst;
798 ip->ip_dst = ip->ip_src;
799
800 /*
801 * Source selection for ICMP replies:
802 *
803 * If the incoming packet was addressed directly to one of our
804 * own addresses, use dst as the src for the reply.
805 */
806 CK_LIST_FOREACH(ia, INADDR_HASH(t.s_addr), ia_hash) {
807 if (t.s_addr == IA_SIN(ia)->sin_addr.s_addr) {
808 t = IA_SIN(ia)->sin_addr;
809 goto match;
810 }
811 }
812
813 /*
814 * If the incoming packet was addressed to one of our broadcast
815 * addresses, use the first non-broadcast address which corresponds
816 * to the incoming interface.
817 */
818 ifp = m->m_pkthdr.rcvif;
819 if (ifp != NULL && ifp->if_flags & IFF_BROADCAST) {
820 CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
821 if (ifa->ifa_addr->sa_family != AF_INET)
822 continue;
823 ia = ifatoia(ifa);
824 if (satosin(&ia->ia_broadaddr)->sin_addr.s_addr ==
825 t.s_addr) {
826 t = IA_SIN(ia)->sin_addr;
827 goto match;
828 }
829 }
830 }
831 /*
832 * If the packet was transiting through us, use the address of
833 * the interface the packet came through in. If that interface
834 * doesn't have a suitable IP address, the normal selection
835 * criteria apply.
836 */
837 if (V_icmp_rfi && ifp != NULL) {
838 CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
839 if (ifa->ifa_addr->sa_family != AF_INET)
840 continue;
841 ia = ifatoia(ifa);
842 t = IA_SIN(ia)->sin_addr;
843 goto match;
844 }
845 }
846 /*
847 * If the incoming packet was not addressed directly to us, use
848 * designated interface for icmp replies specified by sysctl
849 * net.inet.icmp.reply_src (default not set). Otherwise continue
850 * with normal source selection.
851 */
852 if (V_reply_src[0] != '\0' && (ifp = ifunit(V_reply_src))) {
853 CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
854 if (ifa->ifa_addr->sa_family != AF_INET)
855 continue;
856 ia = ifatoia(ifa);
857 t = IA_SIN(ia)->sin_addr;
858 goto match;
859 }
860 }
861 /*
862 * If the packet was transiting through us, use the address of
863 * the interface that is the closest to the packet source.
864 * When we don't have a route back to the packet source, stop here
865 * and drop the packet.
866 */
867 nh = fib4_lookup(M_GETFIB(m), ip->ip_dst, 0, NHR_NONE, 0);
868 if (nh == NULL) {
869 m_freem(m);
870 ICMPSTAT_INC(icps_noroute);
871 goto done;
872 }
873 t = IA_SIN(ifatoia(nh->nh_ifa))->sin_addr;
874 match:
875 #ifdef MAC
876 mac_netinet_icmp_replyinplace(m);
877 #endif
878 ip->ip_src = t;
879 ip->ip_ttl = V_ip_defttl;
880
881 if (optlen > 0) {
882 u_char *cp;
883 int opt, cnt;
884 u_int len;
885
886 /*
887 * Retrieve any source routing from the incoming packet;
888 * add on any record-route or timestamp options.
889 */
890 cp = (u_char *) (ip + 1);
891 if ((opts = ip_srcroute(m)) == NULL &&
892 (opts = m_gethdr(M_NOWAIT, MT_DATA))) {
893 opts->m_len = sizeof(struct in_addr);
894 mtod(opts, struct in_addr *)->s_addr = 0;
895 }
896 if (opts) {
897 #ifdef ICMPPRINTFS
898 if (icmpprintfs)
899 printf("icmp_reflect optlen %d rt %d => ",
900 optlen, opts->m_len);
901 #endif
902 for (cnt = optlen; cnt > 0; cnt -= len, cp += len) {
903 opt = cp[IPOPT_OPTVAL];
904 if (opt == IPOPT_EOL)
905 break;
906 if (opt == IPOPT_NOP)
907 len = 1;
908 else {
909 if (cnt < IPOPT_OLEN + sizeof(*cp))
910 break;
911 len = cp[IPOPT_OLEN];
912 if (len < IPOPT_OLEN + sizeof(*cp) ||
913 len > cnt)
914 break;
915 }
916 /*
917 * Should check for overflow, but it "can't happen"
918 */
919 if (opt == IPOPT_RR || opt == IPOPT_TS ||
920 opt == IPOPT_SECURITY) {
921 bcopy((caddr_t)cp,
922 mtod(opts, caddr_t) + opts->m_len, len);
923 opts->m_len += len;
924 }
925 }
926 /* Terminate & pad, if necessary */
927 cnt = opts->m_len % 4;
928 if (cnt) {
929 for (; cnt < 4; cnt++) {
930 *(mtod(opts, caddr_t) + opts->m_len) =
931 IPOPT_EOL;
932 opts->m_len++;
933 }
934 }
935 #ifdef ICMPPRINTFS
936 if (icmpprintfs)
937 printf("%d\n", opts->m_len);
938 #endif
939 }
940 ip_stripoptions(m);
941 }
942 m_tag_delete_nonpersistent(m);
943 m->m_flags &= ~(M_BCAST|M_MCAST);
944 icmp_send(m, opts);
945 done:
946 if (opts)
947 (void)m_free(opts);
948 }
949
950 /*
951 * Verifies if redirect message is valid, according to RFC 1122
952 *
953 * @src: sockaddr with address of redirect originator
954 * @dst: sockaddr with destination in question
955 * @gateway: new proposed gateway
956 *
957 * Returns 0 on success.
958 */
959 static int
icmp_verify_redirect_gateway(struct sockaddr_in * src,struct sockaddr_in * dst,struct sockaddr_in * gateway,u_int fibnum)960 icmp_verify_redirect_gateway(struct sockaddr_in *src, struct sockaddr_in *dst,
961 struct sockaddr_in *gateway, u_int fibnum)
962 {
963 struct nhop_object *nh;
964 struct ifaddr *ifa;
965
966 NET_EPOCH_ASSERT();
967
968 /* Verify the gateway is directly reachable. */
969 if ((ifa = ifa_ifwithnet((struct sockaddr *)gateway, 0, fibnum))==NULL)
970 return (ENETUNREACH);
971
972 /* TODO: fib-aware. */
973 if (ifa_ifwithaddr_check((struct sockaddr *)gateway))
974 return (EHOSTUNREACH);
975
976 nh = fib4_lookup(fibnum, dst->sin_addr, 0, NHR_NONE, 0);
977 if (nh == NULL)
978 return (EINVAL);
979
980 /*
981 * If the redirect isn't from our current router for this dst,
982 * it's either old or wrong. If it redirects us to ourselves,
983 * we have a routing loop, perhaps as a result of an interface
984 * going down recently.
985 */
986 if (!sa_equal((struct sockaddr *)src, &nh->gw_sa))
987 return (EINVAL);
988 if (nh->nh_ifa != ifa && ifa->ifa_addr->sa_family != AF_LINK)
989 return (EINVAL);
990
991 /* If host route already exists, ignore redirect. */
992 if (nh->nh_flags & NHF_HOST)
993 return (EEXIST);
994
995 /* If the prefix is directly reachable, ignore redirect. */
996 if (!(nh->nh_flags & NHF_GATEWAY))
997 return (EEXIST);
998
999 return (0);
1000 }
1001
1002 /*
1003 * Send an icmp packet back to the ip level,
1004 * after supplying a checksum.
1005 */
1006 static void
icmp_send(struct mbuf * m,struct mbuf * opts)1007 icmp_send(struct mbuf *m, struct mbuf *opts)
1008 {
1009 struct ip *ip = mtod(m, struct ip *);
1010 int hlen;
1011 struct icmp *icp;
1012
1013 hlen = ip->ip_hl << 2;
1014 m->m_data += hlen;
1015 m->m_len -= hlen;
1016 icp = mtod(m, struct icmp *);
1017 icp->icmp_cksum = 0;
1018 icp->icmp_cksum = in_cksum(m, ntohs(ip->ip_len) - hlen);
1019 m->m_data -= hlen;
1020 m->m_len += hlen;
1021 m->m_pkthdr.rcvif = (struct ifnet *)0;
1022 #ifdef ICMPPRINTFS
1023 if (icmpprintfs) {
1024 char dstbuf[INET_ADDRSTRLEN];
1025 char srcbuf[INET_ADDRSTRLEN];
1026
1027 printf("icmp_send dst %s src %s\n",
1028 inet_ntoa_r(ip->ip_dst, dstbuf),
1029 inet_ntoa_r(ip->ip_src, srcbuf));
1030 }
1031 #endif
1032 (void) ip_output(m, opts, NULL, 0, NULL, NULL);
1033 }
1034
1035 /*
1036 * Return milliseconds since 00:00 UTC in network format.
1037 */
1038 uint32_t
iptime(void)1039 iptime(void)
1040 {
1041 struct timeval atv;
1042 u_long t;
1043
1044 getmicrotime(&atv);
1045 t = (atv.tv_sec % (24*60*60)) * 1000 + atv.tv_usec / 1000;
1046 return (htonl(t));
1047 }
1048
1049 /*
1050 * Return the next larger or smaller MTU plateau (table from RFC 1191)
1051 * given current value MTU. If DIR is less than zero, a larger plateau
1052 * is returned; otherwise, a smaller value is returned.
1053 */
1054 int
ip_next_mtu(int mtu,int dir)1055 ip_next_mtu(int mtu, int dir)
1056 {
1057 static int mtutab[] = {
1058 65535, 32000, 17914, 8166, 4352, 2002, 1492, 1280, 1006, 508,
1059 296, 68, 0
1060 };
1061 int i, size;
1062
1063 size = (sizeof mtutab) / (sizeof mtutab[0]);
1064 if (dir >= 0) {
1065 for (i = 0; i < size; i++)
1066 if (mtu > mtutab[i])
1067 return mtutab[i];
1068 } else {
1069 for (i = size - 1; i >= 0; i--)
1070 if (mtu < mtutab[i])
1071 return mtutab[i];
1072 if (mtu == mtutab[0])
1073 return mtutab[0];
1074 }
1075 return 0;
1076 }
1077 #endif /* INET */
1078
1079 /*
1080 * badport_bandlim() - check for ICMP bandwidth limit
1081 *
1082 * Return 0 if it is ok to send an ICMP error response, -1 if we have
1083 * hit our bandwidth limit and it is not ok.
1084 *
1085 * If icmplim is <= 0, the feature is disabled and 0 is returned.
1086 *
1087 * For now we separate the TCP and UDP subsystems w/ different 'which'
1088 * values. We may eventually remove this separation (and simplify the
1089 * code further).
1090 *
1091 * Note that the printing of the error message is delayed so we can
1092 * properly print the icmp error rate that the system was trying to do
1093 * (i.e. 22000/100 pps, etc...). This can cause long delays in printing
1094 * the 'final' error, but it doesn't make sense to solve the printing
1095 * delay with more complex code.
1096 */
1097 VNET_DEFINE_STATIC(struct counter_rate, icmp_rates[BANDLIM_MAX]);
1098 #define V_icmp_rates VNET(icmp_rates)
1099
1100 static const char *icmp_rate_descrs[BANDLIM_MAX] = {
1101 [BANDLIM_ICMP_UNREACH] = "icmp unreach",
1102 [BANDLIM_ICMP_ECHO] = "icmp ping",
1103 [BANDLIM_ICMP_TSTAMP] = "icmp tstamp",
1104 [BANDLIM_RST_CLOSEDPORT] = "closed port RST",
1105 [BANDLIM_RST_OPENPORT] = "open port RST",
1106 [BANDLIM_ICMP6_UNREACH] = "icmp6 unreach",
1107 [BANDLIM_SCTP_OOTB] = "sctp ootb",
1108 };
1109
1110 static void
icmplim_new_jitter(void)1111 icmplim_new_jitter(void)
1112 {
1113 /*
1114 * Adjust limit +/- to jitter the measurement to deny a side-channel
1115 * port scan as in https://dl.acm.org/doi/10.1145/3372297.3417280
1116 */
1117 if (V_icmplim_jitter > 0)
1118 V_icmplim_curr_jitter =
1119 arc4random_uniform(V_icmplim_jitter * 2 + 1) -
1120 V_icmplim_jitter;
1121 }
1122
1123 static int
sysctl_icmplim_and_jitter(SYSCTL_HANDLER_ARGS)1124 sysctl_icmplim_and_jitter(SYSCTL_HANDLER_ARGS)
1125 {
1126 uint32_t new;
1127 int error;
1128 bool lim;
1129
1130 MPASS(oidp->oid_arg1 == &VNET_NAME(icmplim) ||
1131 oidp->oid_arg1 == &VNET_NAME(icmplim_jitter));
1132
1133 lim = (oidp->oid_arg1 == &VNET_NAME(icmplim));
1134 new = lim ? V_icmplim : V_icmplim_jitter;
1135 error = sysctl_handle_int(oidp, &new, 0, req);
1136 if (error == 0 && req->newptr) {
1137 if (lim) {
1138 if (new != 0 && new <= V_icmplim_jitter)
1139 error = EINVAL;
1140 else
1141 V_icmplim = new;
1142 } else {
1143 if (new >= V_icmplim)
1144 error = EINVAL;
1145 else {
1146 V_icmplim_jitter = new;
1147 icmplim_new_jitter();
1148 }
1149 }
1150 }
1151 MPASS(V_icmplim + V_icmplim_curr_jitter >= 0);
1152
1153 return (error);
1154 }
1155
1156 static void
icmp_bandlimit_init(void)1157 icmp_bandlimit_init(void)
1158 {
1159
1160 for (int i = 0; i < BANDLIM_MAX; i++) {
1161 V_icmp_rates[i].cr_rate = counter_u64_alloc(M_WAITOK);
1162 V_icmp_rates[i].cr_ticks = ticks;
1163 }
1164 icmplim_new_jitter();
1165 }
1166 VNET_SYSINIT(icmp_bandlimit, SI_SUB_PROTO_DOMAIN, SI_ORDER_ANY,
1167 icmp_bandlimit_init, NULL);
1168
1169 #ifdef VIMAGE
1170 static void
icmp_bandlimit_uninit(void)1171 icmp_bandlimit_uninit(void)
1172 {
1173
1174 for (int i = 0; i < BANDLIM_MAX; i++)
1175 counter_u64_free(V_icmp_rates[i].cr_rate);
1176 }
1177 VNET_SYSUNINIT(icmp_bandlimit, SI_SUB_PROTO_DOMAIN, SI_ORDER_THIRD,
1178 icmp_bandlimit_uninit, NULL);
1179 #endif
1180
1181 int
badport_bandlim(int which)1182 badport_bandlim(int which)
1183 {
1184 int64_t pps;
1185
1186 if (V_icmplim == 0 || which == BANDLIM_UNLIMITED)
1187 return (0);
1188
1189 KASSERT(which >= 0 && which < BANDLIM_MAX,
1190 ("%s: which %d", __func__, which));
1191
1192 pps = counter_ratecheck(&V_icmp_rates[which], V_icmplim +
1193 V_icmplim_curr_jitter);
1194 if (pps > 0) {
1195 if (V_icmplim_output)
1196 log(LOG_NOTICE,
1197 "Limiting %s response from %jd to %d packets/sec\n",
1198 icmp_rate_descrs[which], (intmax_t )pps,
1199 V_icmplim + V_icmplim_curr_jitter);
1200 icmplim_new_jitter();
1201 }
1202 if (pps == -1)
1203 return (-1);
1204 return (0);
1205 }
1206