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[BANDLIM_MAX]) = {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 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 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 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 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 if (in_broadcast(ip->ip_dst)) 639 icmpdst.sin_addr = ip->ip_src; 640 else 641 icmpdst.sin_addr = ip->ip_dst; 642 ia = (struct in_ifaddr *)ifaof_ifpforaddr( 643 (struct sockaddr *)&icmpdst, m->m_pkthdr.rcvif); 644 if (ia == NULL) 645 break; 646 if (ia->ia_ifp == NULL) 647 break; 648 icp->icmp_type = ICMP_MASKREPLY; 649 if (V_icmpmaskfake == 0) 650 icp->icmp_mask = ia->ia_sockmask.sin_addr.s_addr; 651 else 652 icp->icmp_mask = V_icmpmaskfake; 653 if (ip->ip_src.s_addr == 0) { 654 if (ia->ia_ifp->if_flags & IFF_BROADCAST) 655 ip->ip_src = satosin(&ia->ia_broadaddr)->sin_addr; 656 else if (ia->ia_ifp->if_flags & IFF_POINTOPOINT) 657 ip->ip_src = satosin(&ia->ia_dstaddr)->sin_addr; 658 } 659 reflect: 660 ICMPSTAT_INC(icps_reflect); 661 ICMPSTAT_INC2(icps_outhist, icp->icmp_type); 662 icmp_reflect(m); 663 return (IPPROTO_DONE); 664 665 case ICMP_REDIRECT: 666 if (V_log_redirect) { 667 u_long src, dst, gw; 668 669 src = ntohl(ip->ip_src.s_addr); 670 dst = ntohl(icp->icmp_ip.ip_dst.s_addr); 671 gw = ntohl(icp->icmp_gwaddr.s_addr); 672 printf("icmp redirect from %d.%d.%d.%d: " 673 "%d.%d.%d.%d => %d.%d.%d.%d\n", 674 (int)(src >> 24), (int)((src >> 16) & 0xff), 675 (int)((src >> 8) & 0xff), (int)(src & 0xff), 676 (int)(dst >> 24), (int)((dst >> 16) & 0xff), 677 (int)((dst >> 8) & 0xff), (int)(dst & 0xff), 678 (int)(gw >> 24), (int)((gw >> 16) & 0xff), 679 (int)((gw >> 8) & 0xff), (int)(gw & 0xff)); 680 } 681 /* 682 * RFC1812 says we must ignore ICMP redirects if we 683 * are acting as router. 684 */ 685 if (V_drop_redirect || V_ipforwarding) 686 break; 687 if (code > 3) 688 goto badcode; 689 if (icmplen < ICMP_ADVLENMIN || icmplen < ICMP_ADVLEN(icp) || 690 icp->icmp_ip.ip_hl < (sizeof(struct ip) >> 2)) { 691 ICMPSTAT_INC(icps_badlen); 692 break; 693 } 694 /* 695 * Short circuit routing redirects to force 696 * immediate change in the kernel's routing 697 * tables. The message is also handed to anyone 698 * listening on a raw socket (e.g. the routing 699 * daemon for use in updating its tables). 700 */ 701 icmpgw.sin_addr = ip->ip_src; 702 icmpdst.sin_addr = icp->icmp_gwaddr; 703 #ifdef ICMPPRINTFS 704 if (icmpprintfs) { 705 char dstbuf[INET_ADDRSTRLEN]; 706 char gwbuf[INET_ADDRSTRLEN]; 707 708 printf("redirect dst %s to %s\n", 709 inet_ntoa_r(icp->icmp_ip.ip_dst, dstbuf), 710 inet_ntoa_r(icp->icmp_gwaddr, gwbuf)); 711 } 712 #endif 713 icmpsrc.sin_addr = icp->icmp_ip.ip_dst; 714 715 /* 716 * RFC 1122 says network (code 0,2) redirects SHOULD 717 * be treated identically to the host redirects. 718 * Given that, ignore network masks. 719 */ 720 721 /* 722 * Variable values: 723 * icmpsrc: route destination 724 * icmpdst: route gateway 725 * icmpgw: message source 726 */ 727 728 if (icmp_verify_redirect_gateway(&icmpgw, &icmpsrc, &icmpdst, 729 M_GETFIB(m)) != 0) { 730 /* TODO: increment bad redirects here */ 731 break; 732 } 733 734 for ( fibnum = 0; fibnum < rt_numfibs; fibnum++) { 735 rib_add_redirect(fibnum, (struct sockaddr *)&icmpsrc, 736 (struct sockaddr *)&icmpdst, 737 (struct sockaddr *)&icmpgw, m->m_pkthdr.rcvif, 738 RTF_GATEWAY, V_redirtimeout); 739 } 740 break; 741 742 /* 743 * No kernel processing for the following; 744 * just fall through to send to raw listener. 745 */ 746 case ICMP_ECHOREPLY: 747 case ICMP_ROUTERADVERT: 748 case ICMP_ROUTERSOLICIT: 749 case ICMP_TSTAMPREPLY: 750 case ICMP_IREQREPLY: 751 case ICMP_MASKREPLY: 752 case ICMP_SOURCEQUENCH: 753 default: 754 break; 755 } 756 757 raw: 758 *mp = m; 759 rip_input(mp, offp, proto); 760 return (IPPROTO_DONE); 761 762 freeit: 763 m_freem(m); 764 return (IPPROTO_DONE); 765 } 766 767 /* 768 * Reflect the ip packet back to the source 769 */ 770 static void 771 icmp_reflect(struct mbuf *m) 772 { 773 struct ip *ip = mtod(m, struct ip *); 774 struct ifaddr *ifa; 775 struct ifnet *ifp; 776 struct in_ifaddr *ia; 777 struct in_addr t; 778 struct nhop_object *nh; 779 struct mbuf *opts = NULL; 780 int optlen = (ip->ip_hl << 2) - sizeof(struct ip); 781 782 NET_EPOCH_ASSERT(); 783 784 if (IN_MULTICAST(ntohl(ip->ip_src.s_addr)) || 785 (IN_EXPERIMENTAL(ntohl(ip->ip_src.s_addr)) && !V_ip_allow_net240) || 786 (IN_ZERONET(ntohl(ip->ip_src.s_addr)) && !V_ip_allow_net0) || 787 in_nullhost(ip->ip_src) ) { 788 m_freem(m); /* Bad return address */ 789 ICMPSTAT_INC(icps_badaddr); 790 goto done; /* ip_output() will check for broadcast */ 791 } 792 793 t = ip->ip_dst; 794 ip->ip_dst = ip->ip_src; 795 796 /* 797 * Source selection for ICMP replies: 798 * 799 * If the incoming packet was addressed directly to one of our 800 * own addresses, use dst as the src for the reply. 801 */ 802 CK_LIST_FOREACH(ia, INADDR_HASH(t.s_addr), ia_hash) { 803 if (t.s_addr == IA_SIN(ia)->sin_addr.s_addr) { 804 t = IA_SIN(ia)->sin_addr; 805 goto match; 806 } 807 } 808 809 /* 810 * If the incoming packet was addressed to one of our broadcast 811 * addresses, use the first non-broadcast address which corresponds 812 * to the incoming interface. 813 */ 814 ifp = m->m_pkthdr.rcvif; 815 if (ifp != NULL && ifp->if_flags & IFF_BROADCAST) { 816 CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 817 if (ifa->ifa_addr->sa_family != AF_INET) 818 continue; 819 ia = ifatoia(ifa); 820 if (satosin(&ia->ia_broadaddr)->sin_addr.s_addr == 821 t.s_addr) { 822 t = IA_SIN(ia)->sin_addr; 823 goto match; 824 } 825 } 826 } 827 /* 828 * If the packet was transiting through us, use the address of 829 * the interface the packet came through in. If that interface 830 * doesn't have a suitable IP address, the normal selection 831 * criteria apply. 832 */ 833 if (V_icmp_rfi && ifp != NULL) { 834 CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 835 if (ifa->ifa_addr->sa_family != AF_INET) 836 continue; 837 ia = ifatoia(ifa); 838 t = IA_SIN(ia)->sin_addr; 839 goto match; 840 } 841 } 842 /* 843 * If the incoming packet was not addressed directly to us, use 844 * designated interface for icmp replies specified by sysctl 845 * net.inet.icmp.reply_src (default not set). Otherwise continue 846 * with normal source selection. 847 */ 848 if (V_reply_src[0] != '\0' && (ifp = ifunit(V_reply_src))) { 849 CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 850 if (ifa->ifa_addr->sa_family != AF_INET) 851 continue; 852 ia = ifatoia(ifa); 853 t = IA_SIN(ia)->sin_addr; 854 goto match; 855 } 856 } 857 /* 858 * If the packet was transiting through us, use the address of 859 * the interface that is the closest to the packet source. 860 * When we don't have a route back to the packet source, stop here 861 * and drop the packet. 862 */ 863 nh = fib4_lookup(M_GETFIB(m), ip->ip_dst, 0, NHR_NONE, 0); 864 if (nh == NULL) { 865 m_freem(m); 866 ICMPSTAT_INC(icps_noroute); 867 goto done; 868 } 869 t = IA_SIN(ifatoia(nh->nh_ifa))->sin_addr; 870 match: 871 #ifdef MAC 872 mac_netinet_icmp_replyinplace(m); 873 #endif 874 ip->ip_src = t; 875 ip->ip_ttl = V_ip_defttl; 876 877 if (optlen > 0) { 878 u_char *cp; 879 int opt, cnt; 880 u_int len; 881 882 /* 883 * Retrieve any source routing from the incoming packet; 884 * add on any record-route or timestamp options. 885 */ 886 cp = (u_char *) (ip + 1); 887 if ((opts = ip_srcroute(m)) == NULL && 888 (opts = m_gethdr(M_NOWAIT, MT_DATA))) { 889 opts->m_len = sizeof(struct in_addr); 890 mtod(opts, struct in_addr *)->s_addr = 0; 891 } 892 if (opts) { 893 #ifdef ICMPPRINTFS 894 if (icmpprintfs) 895 printf("icmp_reflect optlen %d rt %d => ", 896 optlen, opts->m_len); 897 #endif 898 for (cnt = optlen; cnt > 0; cnt -= len, cp += len) { 899 opt = cp[IPOPT_OPTVAL]; 900 if (opt == IPOPT_EOL) 901 break; 902 if (opt == IPOPT_NOP) 903 len = 1; 904 else { 905 if (cnt < IPOPT_OLEN + sizeof(*cp)) 906 break; 907 len = cp[IPOPT_OLEN]; 908 if (len < IPOPT_OLEN + sizeof(*cp) || 909 len > cnt) 910 break; 911 } 912 /* 913 * Should check for overflow, but it "can't happen" 914 */ 915 if (opt == IPOPT_RR || opt == IPOPT_TS || 916 opt == IPOPT_SECURITY) { 917 bcopy((caddr_t)cp, 918 mtod(opts, caddr_t) + opts->m_len, len); 919 opts->m_len += len; 920 } 921 } 922 /* Terminate & pad, if necessary */ 923 cnt = opts->m_len % 4; 924 if (cnt) { 925 for (; cnt < 4; cnt++) { 926 *(mtod(opts, caddr_t) + opts->m_len) = 927 IPOPT_EOL; 928 opts->m_len++; 929 } 930 } 931 #ifdef ICMPPRINTFS 932 if (icmpprintfs) 933 printf("%d\n", opts->m_len); 934 #endif 935 } 936 ip_stripoptions(m); 937 } 938 m_tag_delete_nonpersistent(m); 939 m->m_flags &= ~(M_BCAST|M_MCAST); 940 icmp_send(m, opts); 941 done: 942 if (opts) 943 (void)m_free(opts); 944 } 945 946 /* 947 * Verifies if redirect message is valid, according to RFC 1122 948 * 949 * @src: sockaddr with address of redirect originator 950 * @dst: sockaddr with destination in question 951 * @gateway: new proposed gateway 952 * 953 * Returns 0 on success. 954 */ 955 static int 956 icmp_verify_redirect_gateway(struct sockaddr_in *src, struct sockaddr_in *dst, 957 struct sockaddr_in *gateway, u_int fibnum) 958 { 959 struct nhop_object *nh; 960 struct ifaddr *ifa; 961 962 NET_EPOCH_ASSERT(); 963 964 /* Verify the gateway is directly reachable. */ 965 if ((ifa = ifa_ifwithnet((struct sockaddr *)gateway, 0, fibnum))==NULL) 966 return (ENETUNREACH); 967 968 /* TODO: fib-aware. */ 969 if (ifa_ifwithaddr_check((struct sockaddr *)gateway)) 970 return (EHOSTUNREACH); 971 972 nh = fib4_lookup(fibnum, dst->sin_addr, 0, NHR_NONE, 0); 973 if (nh == NULL) 974 return (EINVAL); 975 976 /* 977 * If the redirect isn't from our current router for this dst, 978 * it's either old or wrong. If it redirects us to ourselves, 979 * we have a routing loop, perhaps as a result of an interface 980 * going down recently. 981 */ 982 if (!sa_equal((struct sockaddr *)src, &nh->gw_sa)) 983 return (EINVAL); 984 if (nh->nh_ifa != ifa && ifa->ifa_addr->sa_family != AF_LINK) 985 return (EINVAL); 986 987 /* If host route already exists, ignore redirect. */ 988 if (nh->nh_flags & NHF_HOST) 989 return (EEXIST); 990 991 /* If the prefix is directly reachable, ignore redirect. */ 992 if (!(nh->nh_flags & NHF_GATEWAY)) 993 return (EEXIST); 994 995 return (0); 996 } 997 998 /* 999 * Send an icmp packet back to the ip level, 1000 * after supplying a checksum. 1001 */ 1002 static void 1003 icmp_send(struct mbuf *m, struct mbuf *opts) 1004 { 1005 struct ip *ip = mtod(m, struct ip *); 1006 int hlen; 1007 struct icmp *icp; 1008 1009 hlen = ip->ip_hl << 2; 1010 m->m_data += hlen; 1011 m->m_len -= hlen; 1012 icp = mtod(m, struct icmp *); 1013 icp->icmp_cksum = 0; 1014 icp->icmp_cksum = in_cksum(m, ntohs(ip->ip_len) - hlen); 1015 m->m_data -= hlen; 1016 m->m_len += hlen; 1017 m->m_pkthdr.rcvif = (struct ifnet *)0; 1018 #ifdef ICMPPRINTFS 1019 if (icmpprintfs) { 1020 char dstbuf[INET_ADDRSTRLEN]; 1021 char srcbuf[INET_ADDRSTRLEN]; 1022 1023 printf("icmp_send dst %s src %s\n", 1024 inet_ntoa_r(ip->ip_dst, dstbuf), 1025 inet_ntoa_r(ip->ip_src, srcbuf)); 1026 } 1027 #endif 1028 (void) ip_output(m, opts, NULL, 0, NULL, NULL); 1029 } 1030 1031 /* 1032 * Return milliseconds since 00:00 UTC in network format. 1033 */ 1034 uint32_t 1035 iptime(void) 1036 { 1037 struct timeval atv; 1038 u_long t; 1039 1040 getmicrotime(&atv); 1041 t = (atv.tv_sec % (24*60*60)) * 1000 + atv.tv_usec / 1000; 1042 return (htonl(t)); 1043 } 1044 1045 /* 1046 * Return the next larger or smaller MTU plateau (table from RFC 1191) 1047 * given current value MTU. If DIR is less than zero, a larger plateau 1048 * is returned; otherwise, a smaller value is returned. 1049 */ 1050 int 1051 ip_next_mtu(int mtu, int dir) 1052 { 1053 static int mtutab[] = { 1054 65535, 32000, 17914, 8166, 4352, 2002, 1492, 1280, 1006, 508, 1055 296, 68, 0 1056 }; 1057 int i, size; 1058 1059 size = (sizeof mtutab) / (sizeof mtutab[0]); 1060 if (dir >= 0) { 1061 for (i = 0; i < size; i++) 1062 if (mtu > mtutab[i]) 1063 return mtutab[i]; 1064 } else { 1065 for (i = size - 1; i >= 0; i--) 1066 if (mtu < mtutab[i]) 1067 return mtutab[i]; 1068 if (mtu == mtutab[0]) 1069 return mtutab[0]; 1070 } 1071 return 0; 1072 } 1073 #endif /* INET */ 1074 1075 /* 1076 * badport_bandlim() - check for ICMP bandwidth limit 1077 * 1078 * Return 0 if it is ok to send an ICMP error response, -1 if we have 1079 * hit our bandwidth limit and it is not ok. 1080 * 1081 * If icmplim is <= 0, the feature is disabled and 0 is returned. 1082 * 1083 * For now we separate the TCP and UDP subsystems w/ different 'which' 1084 * values. We may eventually remove this separation (and simplify the 1085 * code further). 1086 * 1087 * Note that the printing of the error message is delayed so we can 1088 * properly print the icmp error rate that the system was trying to do 1089 * (i.e. 22000/100 pps, etc...). This can cause long delays in printing 1090 * the 'final' error, but it doesn't make sense to solve the printing 1091 * delay with more complex code. 1092 */ 1093 VNET_DEFINE_STATIC(struct counter_rate, icmp_rates[BANDLIM_MAX]); 1094 #define V_icmp_rates VNET(icmp_rates) 1095 1096 static const char *icmp_rate_descrs[BANDLIM_MAX] = { 1097 [BANDLIM_ICMP_UNREACH] = "icmp unreach", 1098 [BANDLIM_ICMP_ECHO] = "icmp ping", 1099 [BANDLIM_ICMP_TSTAMP] = "icmp tstamp", 1100 [BANDLIM_RST_CLOSEDPORT] = "closed port RST", 1101 [BANDLIM_RST_OPENPORT] = "open port RST", 1102 [BANDLIM_ICMP6_UNREACH] = "icmp6 unreach", 1103 [BANDLIM_SCTP_OOTB] = "sctp ootb", 1104 }; 1105 1106 static void 1107 icmplim_new_jitter(int which) 1108 { 1109 /* 1110 * Adjust limit +/- to jitter the measurement to deny a side-channel 1111 * port scan as in https://dl.acm.org/doi/10.1145/3372297.3417280 1112 */ 1113 KASSERT(which >= 0 && which < BANDLIM_MAX, 1114 ("%s: which %d", __func__, which)); 1115 if (V_icmplim_jitter > 0) 1116 V_icmplim_curr_jitter[which] = 1117 arc4random_uniform(V_icmplim_jitter * 2 + 1) - 1118 V_icmplim_jitter; 1119 } 1120 1121 static int 1122 sysctl_icmplim_and_jitter(SYSCTL_HANDLER_ARGS) 1123 { 1124 uint32_t new; 1125 int error; 1126 bool lim; 1127 1128 MPASS(oidp->oid_arg1 == &VNET_NAME(icmplim) || 1129 oidp->oid_arg1 == &VNET_NAME(icmplim_jitter)); 1130 1131 lim = (oidp->oid_arg1 == &VNET_NAME(icmplim)); 1132 new = lim ? V_icmplim : V_icmplim_jitter; 1133 error = sysctl_handle_int(oidp, &new, 0, req); 1134 if (error == 0 && req->newptr) { 1135 if (lim) { 1136 if (new != 0 && new <= V_icmplim_jitter) 1137 error = EINVAL; 1138 else 1139 V_icmplim = new; 1140 } else { 1141 if (new >= V_icmplim) 1142 error = EINVAL; 1143 else { 1144 V_icmplim_jitter = new; 1145 for (int i = 0; i < BANDLIM_MAX; i++) { 1146 icmplim_new_jitter(i); 1147 } 1148 } 1149 } 1150 } 1151 MPASS(V_icmplim == 0 || V_icmplim > V_icmplim_jitter); 1152 1153 return (error); 1154 } 1155 1156 static 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 icmplim_new_jitter(i); 1164 } 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 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 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[which]); 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[which]); 1200 icmplim_new_jitter(which); 1201 } 1202 if (pps == -1) 1203 return (-1); 1204 return (0); 1205 } 1206