ip_icmp.c revision 1.132.2.1
1 /* $NetBSD: ip_icmp.c,v 1.132.2.1 2014/08/10 06:56:25 tls 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, 2000 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 * This code is derived from software contributed to The NetBSD Foundation 41 * by Jason R. Thorpe of Zembu Labs, Inc. 42 * 43 * Redistribution and use in source and binary forms, with or without 44 * modification, are permitted provided that the following conditions 45 * are met: 46 * 1. Redistributions of source code must retain the above copyright 47 * notice, this list of conditions and the following disclaimer. 48 * 2. Redistributions in binary form must reproduce the above copyright 49 * notice, this list of conditions and the following disclaimer in the 50 * documentation and/or other materials provided with the distribution. 51 * 52 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 53 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 54 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 55 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 56 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 57 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 58 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 59 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 60 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 61 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 62 * POSSIBILITY OF SUCH DAMAGE. 63 */ 64 65 /* 66 * Copyright (c) 1982, 1986, 1988, 1993 67 * The Regents of the University of California. All rights reserved. 68 * 69 * Redistribution and use in source and binary forms, with or without 70 * modification, are permitted provided that the following conditions 71 * are met: 72 * 1. Redistributions of source code must retain the above copyright 73 * notice, this list of conditions and the following disclaimer. 74 * 2. Redistributions in binary form must reproduce the above copyright 75 * notice, this list of conditions and the following disclaimer in the 76 * documentation and/or other materials provided with the distribution. 77 * 3. Neither the name of the University nor the names of its contributors 78 * may be used to endorse or promote products derived from this software 79 * without specific prior written permission. 80 * 81 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 82 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 83 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 84 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 85 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 86 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 87 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 88 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 89 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 90 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 91 * SUCH DAMAGE. 92 * 93 * @(#)ip_icmp.c 8.2 (Berkeley) 1/4/94 94 */ 95 96 #include <sys/cdefs.h> 97 __KERNEL_RCSID(0, "$NetBSD: ip_icmp.c,v 1.132.2.1 2014/08/10 06:56:25 tls Exp $"); 98 99 #include "opt_ipsec.h" 100 101 #include <sys/param.h> 102 #include <sys/systm.h> 103 #include <sys/mbuf.h> 104 #include <sys/protosw.h> 105 #include <sys/socket.h> 106 #include <sys/kmem.h> 107 #include <sys/time.h> 108 #include <sys/kernel.h> 109 #include <sys/syslog.h> 110 #include <sys/sysctl.h> 111 112 #include <net/if.h> 113 #include <net/route.h> 114 115 #include <netinet/in.h> 116 #include <netinet/in_systm.h> 117 #include <netinet/in_var.h> 118 #include <netinet/ip.h> 119 #include <netinet/ip_icmp.h> 120 #include <netinet/ip_var.h> 121 #include <netinet/in_pcb.h> 122 #include <netinet/in_proto.h> 123 #include <netinet/icmp_var.h> 124 #include <netinet/icmp_private.h> 125 126 #ifdef IPSEC 127 #include <netipsec/ipsec.h> 128 #include <netipsec/key.h> 129 #endif /* IPSEC*/ 130 131 /* 132 * ICMP routines: error generation, receive packet processing, and 133 * routines to turnaround packets back to the originator, and 134 * host table maintenance routines. 135 */ 136 137 int icmpmaskrepl = 0; 138 int icmpbmcastecho = 0; 139 #ifdef ICMPPRINTFS 140 int icmpprintfs = 0; 141 #endif 142 int icmpreturndatabytes = 8; 143 144 percpu_t *icmpstat_percpu; 145 146 /* 147 * List of callbacks to notify when Path MTU changes are made. 148 */ 149 struct icmp_mtudisc_callback { 150 LIST_ENTRY(icmp_mtudisc_callback) mc_list; 151 void (*mc_func)(struct in_addr); 152 }; 153 154 LIST_HEAD(, icmp_mtudisc_callback) icmp_mtudisc_callbacks = 155 LIST_HEAD_INITIALIZER(&icmp_mtudisc_callbacks); 156 157 #if 0 158 static u_int ip_next_mtu(u_int, int); 159 #else 160 /*static*/ u_int ip_next_mtu(u_int, int); 161 #endif 162 163 extern int icmperrppslim; 164 static int icmperrpps_count = 0; 165 static struct timeval icmperrppslim_last; 166 static int icmp_rediraccept = 1; 167 static int icmp_redirtimeout = 600; 168 static struct rttimer_queue *icmp_redirect_timeout_q = NULL; 169 170 static void icmp_mtudisc_timeout(struct rtentry *, struct rttimer *); 171 static void icmp_redirect_timeout(struct rtentry *, struct rttimer *); 172 173 static void sysctl_netinet_icmp_setup(struct sysctllog **); 174 175 void 176 icmp_init(void) 177 { 178 179 sysctl_netinet_icmp_setup(NULL); 180 181 /* 182 * This is only useful if the user initializes redirtimeout to 183 * something other than zero. 184 */ 185 if (icmp_redirtimeout != 0) { 186 icmp_redirect_timeout_q = 187 rt_timer_queue_create(icmp_redirtimeout); 188 } 189 190 icmpstat_percpu = percpu_alloc(sizeof(uint64_t) * ICMP_NSTATS); 191 } 192 193 /* 194 * Register a Path MTU Discovery callback. 195 */ 196 void 197 icmp_mtudisc_callback_register(void (*func)(struct in_addr)) 198 { 199 struct icmp_mtudisc_callback *mc; 200 201 for (mc = LIST_FIRST(&icmp_mtudisc_callbacks); mc != NULL; 202 mc = LIST_NEXT(mc, mc_list)) { 203 if (mc->mc_func == func) 204 return; 205 } 206 207 mc = kmem_alloc(sizeof(*mc), KM_SLEEP); 208 mc->mc_func = func; 209 LIST_INSERT_HEAD(&icmp_mtudisc_callbacks, mc, mc_list); 210 } 211 212 /* 213 * Generate an error packet of type error 214 * in response to bad packet ip. 215 */ 216 void 217 icmp_error(struct mbuf *n, int type, int code, n_long dest, 218 int destmtu) 219 { 220 struct ip *oip = mtod(n, struct ip *), *nip; 221 unsigned oiplen = oip->ip_hl << 2; 222 struct icmp *icp; 223 struct mbuf *m; 224 struct m_tag *mtag; 225 unsigned icmplen, mblen; 226 227 #ifdef ICMPPRINTFS 228 if (icmpprintfs) 229 printf("icmp_error(%p, type:%d, code:%d)\n", oip, type, code); 230 #endif 231 if (type != ICMP_REDIRECT) 232 ICMP_STATINC(ICMP_STAT_ERROR); 233 /* 234 * Don't send error if the original packet was encrypted. 235 * Don't send error if not the first fragment of message. 236 * Don't error if the old packet protocol was ICMP 237 * error message, only known informational types. 238 */ 239 if (n->m_flags & M_DECRYPTED) 240 goto freeit; 241 if (oip->ip_off &~ htons(IP_MF|IP_DF)) 242 goto freeit; 243 if (oip->ip_p == IPPROTO_ICMP && type != ICMP_REDIRECT && 244 n->m_len >= oiplen + ICMP_MINLEN && 245 !ICMP_INFOTYPE(((struct icmp *)((char *)oip + oiplen))->icmp_type)) { 246 ICMP_STATINC(ICMP_STAT_OLDICMP); 247 goto freeit; 248 } 249 /* Don't send error in response to a multicast or broadcast packet */ 250 if (n->m_flags & (M_BCAST|M_MCAST)) 251 goto freeit; 252 253 /* 254 * First, do a rate limitation check. 255 */ 256 if (icmp_ratelimit(&oip->ip_src, type, code)) { 257 /* XXX stat */ 258 goto freeit; 259 } 260 261 /* 262 * Now, formulate icmp message 263 */ 264 icmplen = oiplen + min(icmpreturndatabytes, 265 ntohs(oip->ip_len) - oiplen); 266 /* 267 * Defend against mbuf chains shorter than oip->ip_len - oiplen: 268 */ 269 mblen = 0; 270 for (m = n; m && (mblen < icmplen); m = m->m_next) 271 mblen += m->m_len; 272 icmplen = min(mblen, icmplen); 273 274 /* 275 * As we are not required to return everything we have, 276 * we return whatever we can return at ease. 277 * 278 * Note that ICMP datagrams longer than 576 octets are out of spec 279 * according to RFC1812; the limit on icmpreturndatabytes below in 280 * icmp_sysctl will keep things below that limit. 281 */ 282 283 KASSERT(ICMP_MINLEN <= MCLBYTES); 284 285 if (icmplen + ICMP_MINLEN > MCLBYTES) 286 icmplen = MCLBYTES - ICMP_MINLEN; 287 288 m = m_gethdr(M_DONTWAIT, MT_HEADER); 289 if (m && (icmplen + ICMP_MINLEN > MHLEN)) { 290 MCLGET(m, M_DONTWAIT); 291 if ((m->m_flags & M_EXT) == 0) { 292 m_freem(m); 293 m = NULL; 294 } 295 } 296 if (m == NULL) 297 goto freeit; 298 MCLAIM(m, n->m_owner); 299 m->m_len = icmplen + ICMP_MINLEN; 300 if ((m->m_flags & M_EXT) == 0) 301 MH_ALIGN(m, m->m_len); 302 else { 303 m->m_data += sizeof(struct ip); 304 m->m_len -= sizeof(struct ip); 305 } 306 icp = mtod(m, struct icmp *); 307 if ((u_int)type > ICMP_MAXTYPE) 308 panic("icmp_error"); 309 ICMP_STATINC(ICMP_STAT_OUTHIST + type); 310 icp->icmp_type = type; 311 if (type == ICMP_REDIRECT) 312 icp->icmp_gwaddr.s_addr = dest; 313 else { 314 icp->icmp_void = 0; 315 /* 316 * The following assignments assume an overlay with the 317 * zeroed icmp_void field. 318 */ 319 if (type == ICMP_PARAMPROB) { 320 icp->icmp_pptr = code; 321 code = 0; 322 } else if (type == ICMP_UNREACH && 323 code == ICMP_UNREACH_NEEDFRAG && destmtu) 324 icp->icmp_nextmtu = htons(destmtu); 325 } 326 327 icp->icmp_code = code; 328 m_copydata(n, 0, icmplen, (void *)&icp->icmp_ip); 329 330 /* 331 * Now, copy old ip header (without options) 332 * in front of icmp message. 333 */ 334 if ((m->m_flags & M_EXT) == 0 && 335 m->m_data - sizeof(struct ip) < m->m_pktdat) 336 panic("icmp len"); 337 m->m_data -= sizeof(struct ip); 338 m->m_len += sizeof(struct ip); 339 m->m_pkthdr.len = m->m_len; 340 m->m_pkthdr.rcvif = n->m_pkthdr.rcvif; 341 nip = mtod(m, struct ip *); 342 /* ip_v set in ip_output */ 343 nip->ip_hl = sizeof(struct ip) >> 2; 344 nip->ip_tos = 0; 345 nip->ip_len = htons(m->m_len); 346 /* ip_id set in ip_output */ 347 nip->ip_off = htons(0); 348 /* ip_ttl set in icmp_reflect */ 349 nip->ip_p = IPPROTO_ICMP; 350 nip->ip_src = oip->ip_src; 351 nip->ip_dst = oip->ip_dst; 352 /* move PF m_tag to new packet, if it exists */ 353 mtag = m_tag_find(n, PACKET_TAG_PF, NULL); 354 if (mtag != NULL) { 355 m_tag_unlink(n, mtag); 356 m_tag_prepend(m, mtag); 357 } 358 icmp_reflect(m); 359 360 freeit: 361 m_freem(n); 362 } 363 364 struct sockaddr_in icmpsrc = { 365 .sin_len = sizeof (struct sockaddr_in), 366 .sin_family = AF_INET, 367 }; 368 static struct sockaddr_in icmpdst = { 369 .sin_len = sizeof (struct sockaddr_in), 370 .sin_family = AF_INET, 371 }; 372 static struct sockaddr_in icmpgw = { 373 .sin_len = sizeof (struct sockaddr_in), 374 .sin_family = AF_INET, 375 }; 376 struct sockaddr_in icmpmask = { 377 .sin_len = 8, 378 .sin_family = 0, 379 }; 380 381 /* 382 * Process a received ICMP message. 383 */ 384 void 385 icmp_input(struct mbuf *m, ...) 386 { 387 int proto; 388 struct icmp *icp; 389 struct ip *ip = mtod(m, struct ip *); 390 int icmplen; 391 int i; 392 struct in_ifaddr *ia; 393 void *(*ctlfunc)(int, const struct sockaddr *, void *); 394 int code; 395 int hlen; 396 va_list ap; 397 struct rtentry *rt; 398 399 va_start(ap, m); 400 hlen = va_arg(ap, int); 401 proto = va_arg(ap, int); 402 va_end(ap); 403 404 /* 405 * Locate icmp structure in mbuf, and check 406 * that not corrupted and of at least minimum length. 407 */ 408 icmplen = ntohs(ip->ip_len) - hlen; 409 #ifdef ICMPPRINTFS 410 if (icmpprintfs) { 411 printf("icmp_input from `%s' to ", inet_ntoa(ip->ip_src)); 412 printf("`%s', len %d\n", inet_ntoa(ip->ip_dst), icmplen); 413 } 414 #endif 415 if (icmplen < ICMP_MINLEN) { 416 ICMP_STATINC(ICMP_STAT_TOOSHORT); 417 goto freeit; 418 } 419 i = hlen + min(icmplen, ICMP_ADVLENMIN); 420 if ((m->m_len < i || M_READONLY(m)) && (m = m_pullup(m, i)) == NULL) { 421 ICMP_STATINC(ICMP_STAT_TOOSHORT); 422 return; 423 } 424 ip = mtod(m, struct ip *); 425 m->m_len -= hlen; 426 m->m_data += hlen; 427 icp = mtod(m, struct icmp *); 428 /* Don't need to assert alignment, here. */ 429 if (in_cksum(m, icmplen)) { 430 ICMP_STATINC(ICMP_STAT_CHECKSUM); 431 goto freeit; 432 } 433 m->m_len += hlen; 434 m->m_data -= hlen; 435 436 #ifdef ICMPPRINTFS 437 /* 438 * Message type specific processing. 439 */ 440 if (icmpprintfs) 441 printf("icmp_input(type:%d, code:%d)\n", icp->icmp_type, 442 icp->icmp_code); 443 #endif 444 if (icp->icmp_type > ICMP_MAXTYPE) 445 goto raw; 446 ICMP_STATINC(ICMP_STAT_INHIST + icp->icmp_type); 447 code = icp->icmp_code; 448 switch (icp->icmp_type) { 449 450 case ICMP_UNREACH: 451 switch (code) { 452 case ICMP_UNREACH_PROTOCOL: 453 code = PRC_UNREACH_PROTOCOL; 454 break; 455 456 case ICMP_UNREACH_PORT: 457 code = PRC_UNREACH_PORT; 458 break; 459 460 case ICMP_UNREACH_SRCFAIL: 461 code = PRC_UNREACH_SRCFAIL; 462 break; 463 464 case ICMP_UNREACH_NEEDFRAG: 465 code = PRC_MSGSIZE; 466 break; 467 468 case ICMP_UNREACH_NET: 469 case ICMP_UNREACH_NET_UNKNOWN: 470 case ICMP_UNREACH_NET_PROHIB: 471 case ICMP_UNREACH_TOSNET: 472 code = PRC_UNREACH_NET; 473 break; 474 475 case ICMP_UNREACH_HOST: 476 case ICMP_UNREACH_HOST_UNKNOWN: 477 case ICMP_UNREACH_ISOLATED: 478 case ICMP_UNREACH_HOST_PROHIB: 479 case ICMP_UNREACH_TOSHOST: 480 case ICMP_UNREACH_ADMIN_PROHIBIT: 481 case ICMP_UNREACH_HOST_PREC: 482 case ICMP_UNREACH_PREC_CUTOFF: 483 code = PRC_UNREACH_HOST; 484 break; 485 486 default: 487 goto badcode; 488 } 489 goto deliver; 490 491 case ICMP_TIMXCEED: 492 if (code > 1) 493 goto badcode; 494 code += PRC_TIMXCEED_INTRANS; 495 goto deliver; 496 497 case ICMP_PARAMPROB: 498 if (code > 1) 499 goto badcode; 500 code = PRC_PARAMPROB; 501 goto deliver; 502 503 case ICMP_SOURCEQUENCH: 504 if (code) 505 goto badcode; 506 code = PRC_QUENCH; 507 goto deliver; 508 509 deliver: 510 /* 511 * Problem with datagram; advise higher level routines. 512 */ 513 if (icmplen < ICMP_ADVLENMIN || icmplen < ICMP_ADVLEN(icp) || 514 icp->icmp_ip.ip_hl < (sizeof(struct ip) >> 2)) { 515 ICMP_STATINC(ICMP_STAT_BADLEN); 516 goto freeit; 517 } 518 if (IN_MULTICAST(icp->icmp_ip.ip_dst.s_addr)) 519 goto badcode; 520 #ifdef ICMPPRINTFS 521 if (icmpprintfs) 522 printf("deliver to protocol %d\n", icp->icmp_ip.ip_p); 523 #endif 524 icmpsrc.sin_addr = icp->icmp_ip.ip_dst; 525 ctlfunc = inetsw[ip_protox[icp->icmp_ip.ip_p]].pr_ctlinput; 526 if (ctlfunc) 527 (void) (*ctlfunc)(code, sintosa(&icmpsrc), 528 &icp->icmp_ip); 529 break; 530 531 badcode: 532 ICMP_STATINC(ICMP_STAT_BADCODE); 533 break; 534 535 case ICMP_ECHO: 536 if (!icmpbmcastecho && 537 (m->m_flags & (M_MCAST | M_BCAST)) != 0) { 538 ICMP_STATINC(ICMP_STAT_BMCASTECHO); 539 break; 540 } 541 icp->icmp_type = ICMP_ECHOREPLY; 542 goto reflect; 543 544 case ICMP_TSTAMP: 545 if (icmplen < ICMP_TSLEN) { 546 ICMP_STATINC(ICMP_STAT_BADLEN); 547 break; 548 } 549 if (!icmpbmcastecho && 550 (m->m_flags & (M_MCAST | M_BCAST)) != 0) { 551 ICMP_STATINC(ICMP_STAT_BMCASTTSTAMP); 552 break; 553 } 554 icp->icmp_type = ICMP_TSTAMPREPLY; 555 icp->icmp_rtime = iptime(); 556 icp->icmp_ttime = icp->icmp_rtime; /* bogus, do later! */ 557 goto reflect; 558 559 case ICMP_MASKREQ: 560 if (icmpmaskrepl == 0) 561 break; 562 /* 563 * We are not able to respond with all ones broadcast 564 * unless we receive it over a point-to-point interface. 565 */ 566 if (icmplen < ICMP_MASKLEN) { 567 ICMP_STATINC(ICMP_STAT_BADLEN); 568 break; 569 } 570 if (ip->ip_dst.s_addr == INADDR_BROADCAST || 571 in_nullhost(ip->ip_dst)) 572 icmpdst.sin_addr = ip->ip_src; 573 else 574 icmpdst.sin_addr = ip->ip_dst; 575 ia = ifatoia(ifaof_ifpforaddr(sintosa(&icmpdst), 576 m->m_pkthdr.rcvif)); 577 if (ia == 0) 578 break; 579 icp->icmp_type = ICMP_MASKREPLY; 580 icp->icmp_mask = ia->ia_sockmask.sin_addr.s_addr; 581 if (in_nullhost(ip->ip_src)) { 582 if (ia->ia_ifp->if_flags & IFF_BROADCAST) 583 ip->ip_src = ia->ia_broadaddr.sin_addr; 584 else if (ia->ia_ifp->if_flags & IFF_POINTOPOINT) 585 ip->ip_src = ia->ia_dstaddr.sin_addr; 586 } 587 reflect: 588 { 589 uint64_t *icps = percpu_getref(icmpstat_percpu); 590 icps[ICMP_STAT_REFLECT]++; 591 icps[ICMP_STAT_OUTHIST + icp->icmp_type]++; 592 percpu_putref(icmpstat_percpu); 593 } 594 icmp_reflect(m); 595 return; 596 597 case ICMP_REDIRECT: 598 if (code > 3) 599 goto badcode; 600 if (icmp_rediraccept == 0) 601 goto freeit; 602 if (icmplen < ICMP_ADVLENMIN || icmplen < ICMP_ADVLEN(icp) || 603 icp->icmp_ip.ip_hl < (sizeof(struct ip) >> 2)) { 604 ICMP_STATINC(ICMP_STAT_BADLEN); 605 break; 606 } 607 /* 608 * Short circuit routing redirects to force 609 * immediate change in the kernel's routing 610 * tables. The message is also handed to anyone 611 * listening on a raw socket (e.g. the routing 612 * daemon for use in updating its tables). 613 */ 614 icmpgw.sin_addr = ip->ip_src; 615 icmpdst.sin_addr = icp->icmp_gwaddr; 616 #ifdef ICMPPRINTFS 617 if (icmpprintfs) { 618 printf("redirect dst `%s' to `%s'\n", 619 inet_ntoa(icp->icmp_ip.ip_dst), 620 inet_ntoa(icp->icmp_gwaddr)); 621 } 622 #endif 623 icmpsrc.sin_addr = icp->icmp_ip.ip_dst; 624 rt = NULL; 625 rtredirect(sintosa(&icmpsrc), sintosa(&icmpdst), 626 NULL, RTF_GATEWAY | RTF_HOST, sintosa(&icmpgw), &rt); 627 if (rt != NULL && icmp_redirtimeout != 0) { 628 i = rt_timer_add(rt, icmp_redirect_timeout, 629 icmp_redirect_timeout_q); 630 if (i) 631 log(LOG_ERR, "ICMP: redirect failed to " 632 "register timeout for route to %x, " 633 "code %d\n", 634 icp->icmp_ip.ip_dst.s_addr, i); 635 } 636 if (rt != NULL) 637 rtfree(rt); 638 639 pfctlinput(PRC_REDIRECT_HOST, sintosa(&icmpsrc)); 640 #if defined(IPSEC) 641 if (ipsec_used) 642 key_sa_routechange((struct sockaddr *)&icmpsrc); 643 #endif 644 break; 645 646 /* 647 * No kernel processing for the following; 648 * just fall through to send to raw listener. 649 */ 650 case ICMP_ECHOREPLY: 651 case ICMP_ROUTERADVERT: 652 case ICMP_ROUTERSOLICIT: 653 case ICMP_TSTAMPREPLY: 654 case ICMP_IREQREPLY: 655 case ICMP_MASKREPLY: 656 default: 657 break; 658 } 659 660 raw: 661 rip_input(m, hlen, proto); 662 return; 663 664 freeit: 665 m_freem(m); 666 return; 667 } 668 669 /* 670 * Reflect the ip packet back to the source 671 */ 672 void 673 icmp_reflect(struct mbuf *m) 674 { 675 struct ip *ip = mtod(m, struct ip *); 676 struct in_ifaddr *ia; 677 struct ifaddr *ifa; 678 struct sockaddr_in *sin = 0; 679 struct in_addr t; 680 struct mbuf *opts = 0; 681 int optlen = (ip->ip_hl << 2) - sizeof(struct ip); 682 683 if (!in_canforward(ip->ip_src) && 684 ((ip->ip_src.s_addr & IN_CLASSA_NET) != 685 htonl(IN_LOOPBACKNET << IN_CLASSA_NSHIFT))) { 686 m_freem(m); /* Bad return address */ 687 goto done; /* ip_output() will check for broadcast */ 688 } 689 t = ip->ip_dst; 690 ip->ip_dst = ip->ip_src; 691 /* 692 * If the incoming packet was addressed directly to us, use 693 * dst as the src for the reply. Otherwise (broadcast or 694 * anonymous), use an address which corresponds to the 695 * incoming interface, with a preference for the address which 696 * corresponds to the route to the destination of the ICMP. 697 */ 698 699 /* Look for packet addressed to us */ 700 INADDR_TO_IA(t, ia); 701 702 /* look for packet sent to broadcast address */ 703 if (ia == NULL && m->m_pkthdr.rcvif && 704 (m->m_pkthdr.rcvif->if_flags & IFF_BROADCAST)) { 705 IFADDR_FOREACH(ifa, m->m_pkthdr.rcvif) { 706 if (ifa->ifa_addr->sa_family != AF_INET) 707 continue; 708 if (in_hosteq(t,ifatoia(ifa)->ia_broadaddr.sin_addr)) { 709 ia = ifatoia(ifa); 710 break; 711 } 712 } 713 } 714 715 if (ia) 716 sin = &ia->ia_addr; 717 718 icmpdst.sin_addr = t; 719 720 /* 721 * if the packet is addressed somewhere else, compute the 722 * source address for packets routed back to the source, and 723 * use that, if it's an address on the interface which 724 * received the packet 725 */ 726 if (sin == NULL && m->m_pkthdr.rcvif) { 727 struct sockaddr_in sin_dst; 728 struct route icmproute; 729 int errornum; 730 731 sockaddr_in_init(&sin_dst, &ip->ip_dst, 0); 732 memset(&icmproute, 0, sizeof(icmproute)); 733 errornum = 0; 734 sin = in_selectsrc(&sin_dst, &icmproute, 0, NULL, &errornum); 735 /* errornum is never used */ 736 rtcache_free(&icmproute); 737 /* check to make sure sin is a source address on rcvif */ 738 if (sin) { 739 t = sin->sin_addr; 740 sin = NULL; 741 INADDR_TO_IA(t, ia); 742 while (ia) { 743 if (ia->ia_ifp == m->m_pkthdr.rcvif) { 744 sin = &ia->ia_addr; 745 break; 746 } 747 NEXT_IA_WITH_SAME_ADDR(ia); 748 } 749 } 750 } 751 752 /* 753 * if it was not addressed to us, but the route doesn't go out 754 * the source interface, pick an address on the source 755 * interface. This can happen when routing is asymmetric, or 756 * when the incoming packet was encapsulated 757 */ 758 if (sin == NULL && m->m_pkthdr.rcvif) { 759 IFADDR_FOREACH(ifa, m->m_pkthdr.rcvif) { 760 if (ifa->ifa_addr->sa_family != AF_INET) 761 continue; 762 sin = &(ifatoia(ifa)->ia_addr); 763 break; 764 } 765 } 766 767 /* 768 * The following happens if the packet was not addressed to us, 769 * and was received on an interface with no IP address: 770 * We find the first AF_INET address on the first non-loopback 771 * interface. 772 */ 773 if (sin == NULL) 774 TAILQ_FOREACH(ia, &in_ifaddrhead, ia_list) { 775 if (ia->ia_ifp->if_flags & IFF_LOOPBACK) 776 continue; 777 sin = &ia->ia_addr; 778 break; 779 } 780 781 /* 782 * If we still didn't find an address, punt. We could have an 783 * interface up (and receiving packets) with no address. 784 */ 785 if (sin == NULL) { 786 m_freem(m); 787 goto done; 788 } 789 790 ip->ip_src = sin->sin_addr; 791 ip->ip_ttl = MAXTTL; 792 793 if (optlen > 0) { 794 u_char *cp; 795 int opt, cnt; 796 u_int len; 797 798 /* 799 * Retrieve any source routing from the incoming packet; 800 * add on any record-route or timestamp options. 801 */ 802 cp = (u_char *) (ip + 1); 803 if ((opts = ip_srcroute()) == 0 && 804 (opts = m_gethdr(M_DONTWAIT, MT_HEADER))) { 805 MCLAIM(opts, m->m_owner); 806 opts->m_len = sizeof(struct in_addr); 807 *mtod(opts, struct in_addr *) = zeroin_addr; 808 } 809 if (opts) { 810 #ifdef ICMPPRINTFS 811 if (icmpprintfs) 812 printf("icmp_reflect optlen %d rt %d => ", 813 optlen, opts->m_len); 814 #endif 815 for (cnt = optlen; cnt > 0; cnt -= len, cp += len) { 816 opt = cp[IPOPT_OPTVAL]; 817 if (opt == IPOPT_EOL) 818 break; 819 if (opt == IPOPT_NOP) 820 len = 1; 821 else { 822 if (cnt < IPOPT_OLEN + sizeof(*cp)) 823 break; 824 len = cp[IPOPT_OLEN]; 825 if (len < IPOPT_OLEN + sizeof(*cp) || 826 len > cnt) 827 break; 828 } 829 /* 830 * Should check for overflow, but it "can't happen" 831 */ 832 if (opt == IPOPT_RR || opt == IPOPT_TS || 833 opt == IPOPT_SECURITY) { 834 memmove(mtod(opts, char *) + opts->m_len, 835 cp, len); 836 opts->m_len += len; 837 } 838 } 839 /* Terminate & pad, if necessary */ 840 if ((cnt = opts->m_len % 4) != 0) { 841 for (; cnt < 4; cnt++) { 842 *(mtod(opts, char *) + opts->m_len) = 843 IPOPT_EOL; 844 opts->m_len++; 845 } 846 } 847 #ifdef ICMPPRINTFS 848 if (icmpprintfs) 849 printf("%d\n", opts->m_len); 850 #endif 851 } 852 /* 853 * Now strip out original options by copying rest of first 854 * mbuf's data back, and adjust the IP length. 855 */ 856 ip->ip_len = htons(ntohs(ip->ip_len) - optlen); 857 ip->ip_hl = sizeof(struct ip) >> 2; 858 m->m_len -= optlen; 859 if (m->m_flags & M_PKTHDR) 860 m->m_pkthdr.len -= optlen; 861 optlen += sizeof(struct ip); 862 memmove(ip + 1, (char *)ip + optlen, 863 (unsigned)(m->m_len - sizeof(struct ip))); 864 } 865 m_tag_delete_nonpersistent(m); 866 m->m_flags &= ~(M_BCAST|M_MCAST); 867 868 /* 869 * Clear any in-bound checksum flags for this packet. 870 */ 871 if (m->m_flags & M_PKTHDR) 872 m->m_pkthdr.csum_flags = 0; 873 874 icmp_send(m, opts); 875 done: 876 if (opts) 877 (void)m_free(opts); 878 } 879 880 /* 881 * Send an icmp packet back to the ip level, 882 * after supplying a checksum. 883 */ 884 void 885 icmp_send(struct mbuf *m, struct mbuf *opts) 886 { 887 struct ip *ip = mtod(m, struct ip *); 888 int hlen; 889 struct icmp *icp; 890 891 hlen = ip->ip_hl << 2; 892 m->m_data += hlen; 893 m->m_len -= hlen; 894 icp = mtod(m, struct icmp *); 895 icp->icmp_cksum = 0; 896 icp->icmp_cksum = in_cksum(m, ntohs(ip->ip_len) - hlen); 897 m->m_data -= hlen; 898 m->m_len += hlen; 899 #ifdef ICMPPRINTFS 900 if (icmpprintfs) { 901 printf("icmp_send to destination `%s' from `%s'\n", 902 inet_ntoa(ip->ip_dst), inet_ntoa(ip->ip_src)); 903 } 904 #endif 905 (void)ip_output(m, opts, NULL, 0, NULL, NULL); 906 } 907 908 n_time 909 iptime(void) 910 { 911 struct timeval atv; 912 u_long t; 913 914 microtime(&atv); 915 t = (atv.tv_sec % (24*60*60)) * 1000 + atv.tv_usec / 1000; 916 return (htonl(t)); 917 } 918 919 /* 920 * sysctl helper routine for net.inet.icmp.returndatabytes. ensures 921 * that the new value is in the correct range. 922 */ 923 static int 924 sysctl_net_inet_icmp_returndatabytes(SYSCTLFN_ARGS) 925 { 926 int error, t; 927 struct sysctlnode node; 928 929 node = *rnode; 930 node.sysctl_data = &t; 931 t = icmpreturndatabytes; 932 error = sysctl_lookup(SYSCTLFN_CALL(&node)); 933 if (error || newp == NULL) 934 return (error); 935 936 if (t < 8 || t > 512) 937 return (EINVAL); 938 icmpreturndatabytes = t; 939 940 return (0); 941 } 942 943 /* 944 * sysctl helper routine for net.inet.icmp.redirtimeout. ensures that 945 * the given value is not less than zero and then resets the timeout 946 * queue. 947 */ 948 static int 949 sysctl_net_inet_icmp_redirtimeout(SYSCTLFN_ARGS) 950 { 951 int error, tmp; 952 struct sysctlnode node; 953 954 node = *rnode; 955 node.sysctl_data = &tmp; 956 tmp = icmp_redirtimeout; 957 error = sysctl_lookup(SYSCTLFN_CALL(&node)); 958 if (error || newp == NULL) 959 return (error); 960 if (tmp < 0) 961 return (EINVAL); 962 icmp_redirtimeout = tmp; 963 964 /* 965 * was it a *defined* side-effect that anyone even *reading* 966 * this value causes these things to happen? 967 */ 968 if (icmp_redirect_timeout_q != NULL) { 969 if (icmp_redirtimeout == 0) { 970 rt_timer_queue_destroy(icmp_redirect_timeout_q, 971 true); 972 icmp_redirect_timeout_q = NULL; 973 } else { 974 rt_timer_queue_change(icmp_redirect_timeout_q, 975 icmp_redirtimeout); 976 } 977 } else if (icmp_redirtimeout > 0) { 978 icmp_redirect_timeout_q = 979 rt_timer_queue_create(icmp_redirtimeout); 980 } 981 982 return (0); 983 } 984 985 static int 986 sysctl_net_inet_icmp_stats(SYSCTLFN_ARGS) 987 { 988 989 return (NETSTAT_SYSCTL(icmpstat_percpu, ICMP_NSTATS)); 990 } 991 992 static void 993 sysctl_netinet_icmp_setup(struct sysctllog **clog) 994 { 995 996 sysctl_createv(clog, 0, NULL, NULL, 997 CTLFLAG_PERMANENT, 998 CTLTYPE_NODE, "inet", NULL, 999 NULL, 0, NULL, 0, 1000 CTL_NET, PF_INET, CTL_EOL); 1001 sysctl_createv(clog, 0, NULL, NULL, 1002 CTLFLAG_PERMANENT, 1003 CTLTYPE_NODE, "icmp", 1004 SYSCTL_DESCR("ICMPv4 related settings"), 1005 NULL, 0, NULL, 0, 1006 CTL_NET, PF_INET, IPPROTO_ICMP, CTL_EOL); 1007 1008 sysctl_createv(clog, 0, NULL, NULL, 1009 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 1010 CTLTYPE_INT, "maskrepl", 1011 SYSCTL_DESCR("Respond to ICMP_MASKREQ messages"), 1012 NULL, 0, &icmpmaskrepl, 0, 1013 CTL_NET, PF_INET, IPPROTO_ICMP, 1014 ICMPCTL_MASKREPL, CTL_EOL); 1015 sysctl_createv(clog, 0, NULL, NULL, 1016 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 1017 CTLTYPE_INT, "returndatabytes", 1018 SYSCTL_DESCR("Number of bytes to return in an ICMP " 1019 "error message"), 1020 sysctl_net_inet_icmp_returndatabytes, 0, 1021 &icmpreturndatabytes, 0, 1022 CTL_NET, PF_INET, IPPROTO_ICMP, 1023 ICMPCTL_RETURNDATABYTES, CTL_EOL); 1024 sysctl_createv(clog, 0, NULL, NULL, 1025 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 1026 CTLTYPE_INT, "errppslimit", 1027 SYSCTL_DESCR("Maximum number of outgoing ICMP error " 1028 "messages per second"), 1029 NULL, 0, &icmperrppslim, 0, 1030 CTL_NET, PF_INET, IPPROTO_ICMP, 1031 ICMPCTL_ERRPPSLIMIT, CTL_EOL); 1032 sysctl_createv(clog, 0, NULL, NULL, 1033 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 1034 CTLTYPE_INT, "rediraccept", 1035 SYSCTL_DESCR("Accept ICMP_REDIRECT messages"), 1036 NULL, 0, &icmp_rediraccept, 0, 1037 CTL_NET, PF_INET, IPPROTO_ICMP, 1038 ICMPCTL_REDIRACCEPT, CTL_EOL); 1039 sysctl_createv(clog, 0, NULL, NULL, 1040 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 1041 CTLTYPE_INT, "redirtimeout", 1042 SYSCTL_DESCR("Lifetime of ICMP_REDIRECT generated " 1043 "routes"), 1044 sysctl_net_inet_icmp_redirtimeout, 0, 1045 &icmp_redirtimeout, 0, 1046 CTL_NET, PF_INET, IPPROTO_ICMP, 1047 ICMPCTL_REDIRTIMEOUT, CTL_EOL); 1048 sysctl_createv(clog, 0, NULL, NULL, 1049 CTLFLAG_PERMANENT, 1050 CTLTYPE_STRUCT, "stats", 1051 SYSCTL_DESCR("ICMP statistics"), 1052 sysctl_net_inet_icmp_stats, 0, NULL, 0, 1053 CTL_NET, PF_INET, IPPROTO_ICMP, ICMPCTL_STATS, 1054 CTL_EOL); 1055 sysctl_createv(clog, 0, NULL, NULL, 1056 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 1057 CTLTYPE_INT, "bmcastecho", 1058 SYSCTL_DESCR("Respond to ICMP_ECHO or ICMP_TIMESTAMP " 1059 "message to the broadcast or multicast"), 1060 NULL, 0, &icmpbmcastecho, 0, 1061 CTL_NET, PF_INET, IPPROTO_ICMP, ICMPCTL_BMCASTECHO, 1062 CTL_EOL); 1063 } 1064 1065 void 1066 icmp_statinc(u_int stat) 1067 { 1068 1069 KASSERT(stat < ICMP_NSTATS); 1070 ICMP_STATINC(stat); 1071 } 1072 1073 /* Table of common MTUs: */ 1074 1075 static const u_int mtu_table[] = { 1076 65535, 65280, 32000, 17914, 9180, 8166, 1077 4352, 2002, 1492, 1006, 508, 296, 68, 0 1078 }; 1079 1080 void 1081 icmp_mtudisc(struct icmp *icp, struct in_addr faddr) 1082 { 1083 struct icmp_mtudisc_callback *mc; 1084 struct sockaddr *dst = sintosa(&icmpsrc); 1085 struct rtentry *rt; 1086 u_long mtu = ntohs(icp->icmp_nextmtu); /* Why a long? IPv6 */ 1087 int error; 1088 1089 rt = rtalloc1(dst, 1); 1090 if (rt == 0) 1091 return; 1092 1093 /* If we didn't get a host route, allocate one */ 1094 1095 if ((rt->rt_flags & RTF_HOST) == 0) { 1096 struct rtentry *nrt; 1097 1098 error = rtrequest((int) RTM_ADD, dst, 1099 (struct sockaddr *) rt->rt_gateway, NULL, 1100 RTF_GATEWAY | RTF_HOST | RTF_DYNAMIC, &nrt); 1101 if (error) { 1102 rtfree(rt); 1103 return; 1104 } 1105 nrt->rt_rmx = rt->rt_rmx; 1106 rtfree(rt); 1107 rt = nrt; 1108 } 1109 error = rt_timer_add(rt, icmp_mtudisc_timeout, ip_mtudisc_timeout_q); 1110 if (error) { 1111 rtfree(rt); 1112 return; 1113 } 1114 1115 if (mtu == 0) { 1116 int i = 0; 1117 1118 mtu = ntohs(icp->icmp_ip.ip_len); 1119 /* Some 4.2BSD-based routers incorrectly adjust the ip_len */ 1120 if (mtu > rt->rt_rmx.rmx_mtu && rt->rt_rmx.rmx_mtu != 0) 1121 mtu -= (icp->icmp_ip.ip_hl << 2); 1122 1123 /* If we still can't guess a value, try the route */ 1124 1125 if (mtu == 0) { 1126 mtu = rt->rt_rmx.rmx_mtu; 1127 1128 /* If no route mtu, default to the interface mtu */ 1129 1130 if (mtu == 0) 1131 mtu = rt->rt_ifp->if_mtu; 1132 } 1133 1134 for (i = 0; i < sizeof(mtu_table) / sizeof(mtu_table[0]); i++) 1135 if (mtu > mtu_table[i]) { 1136 mtu = mtu_table[i]; 1137 break; 1138 } 1139 } 1140 1141 /* 1142 * XXX: RTV_MTU is overloaded, since the admin can set it 1143 * to turn off PMTU for a route, and the kernel can 1144 * set it to indicate a serious problem with PMTU 1145 * on a route. We should be using a separate flag 1146 * for the kernel to indicate this. 1147 */ 1148 1149 if ((rt->rt_rmx.rmx_locks & RTV_MTU) == 0) { 1150 if (mtu < 296 || mtu > rt->rt_ifp->if_mtu) 1151 rt->rt_rmx.rmx_locks |= RTV_MTU; 1152 else if (rt->rt_rmx.rmx_mtu > mtu || 1153 rt->rt_rmx.rmx_mtu == 0) { 1154 ICMP_STATINC(ICMP_STAT_PMTUCHG); 1155 rt->rt_rmx.rmx_mtu = mtu; 1156 } 1157 } 1158 1159 if (rt) 1160 rtfree(rt); 1161 1162 /* 1163 * Notify protocols that the MTU for this destination 1164 * has changed. 1165 */ 1166 for (mc = LIST_FIRST(&icmp_mtudisc_callbacks); mc != NULL; 1167 mc = LIST_NEXT(mc, mc_list)) 1168 (*mc->mc_func)(faddr); 1169 } 1170 1171 /* 1172 * Return the next larger or smaller MTU plateau (table from RFC 1191) 1173 * given current value MTU. If DIR is less than zero, a larger plateau 1174 * is returned; otherwise, a smaller value is returned. 1175 */ 1176 u_int 1177 ip_next_mtu(u_int mtu, int dir) /* XXX */ 1178 { 1179 int i; 1180 1181 for (i = 0; i < (sizeof mtu_table) / (sizeof mtu_table[0]); i++) { 1182 if (mtu >= mtu_table[i]) 1183 break; 1184 } 1185 1186 if (dir < 0) { 1187 if (i == 0) { 1188 return 0; 1189 } else { 1190 return mtu_table[i - 1]; 1191 } 1192 } else { 1193 if (mtu_table[i] == 0) { 1194 return 0; 1195 } else if (mtu > mtu_table[i]) { 1196 return mtu_table[i]; 1197 } else { 1198 return mtu_table[i + 1]; 1199 } 1200 } 1201 } 1202 1203 static void 1204 icmp_mtudisc_timeout(struct rtentry *rt, struct rttimer *r) 1205 { 1206 if (rt == NULL) 1207 panic("icmp_mtudisc_timeout: bad route to timeout"); 1208 if ((rt->rt_flags & (RTF_DYNAMIC | RTF_HOST)) == 1209 (RTF_DYNAMIC | RTF_HOST)) { 1210 rtrequest((int) RTM_DELETE, rt_getkey(rt), 1211 rt->rt_gateway, rt_mask(rt), rt->rt_flags, 0); 1212 } else { 1213 if ((rt->rt_rmx.rmx_locks & RTV_MTU) == 0) { 1214 rt->rt_rmx.rmx_mtu = 0; 1215 } 1216 } 1217 } 1218 1219 static void 1220 icmp_redirect_timeout(struct rtentry *rt, struct rttimer *r) 1221 { 1222 if (rt == NULL) 1223 panic("icmp_redirect_timeout: bad route to timeout"); 1224 if ((rt->rt_flags & (RTF_DYNAMIC | RTF_HOST)) == 1225 (RTF_DYNAMIC | RTF_HOST)) { 1226 rtrequest((int) RTM_DELETE, rt_getkey(rt), 1227 rt->rt_gateway, rt_mask(rt), rt->rt_flags, 0); 1228 } 1229 } 1230 1231 /* 1232 * Perform rate limit check. 1233 * Returns 0 if it is okay to send the icmp packet. 1234 * Returns 1 if the router SHOULD NOT send this icmp packet due to rate 1235 * limitation. 1236 * 1237 * XXX per-destination/type check necessary? 1238 */ 1239 int 1240 icmp_ratelimit(const struct in_addr *dst, const int type, 1241 const int code) 1242 { 1243 1244 /* PPS limit */ 1245 if (!ppsratecheck(&icmperrppslim_last, &icmperrpps_count, 1246 icmperrppslim)) { 1247 /* The packet is subject to rate limit */ 1248 return 1; 1249 } 1250 1251 /* okay to send */ 1252 return 0; 1253 } 1254
Indexes created Fri Oct 03 02:09:57 GMT 2025