1 /* 2 * Copyright (c) 1982, 1986, 1988, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. Neither the name of the University nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * @(#)ip_icmp.c 8.2 (Berkeley) 1/4/94 30 * $FreeBSD: src/sys/netinet/ip_icmp.c,v 1.39.2.19 2003/01/24 05:11:34 sam Exp $ 31 */ 32 33 #include "opt_ipsec.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/socketops.h> 41 #include <sys/time.h> 42 #include <sys/kernel.h> 43 #include <sys/sysctl.h> 44 #include <sys/in_cksum.h> 45 46 #include <machine/stdarg.h> 47 48 #include <net/if.h> 49 #include <net/if_types.h> 50 #include <net/netisr2.h> 51 #include <net/netmsg2.h> 52 #include <net/route.h> 53 54 #define _IP_VHL 55 #include <netinet/in.h> 56 #include <netinet/in_systm.h> 57 #include <netinet/in_var.h> 58 #include <netinet/ip.h> 59 #include <netinet/ip_icmp.h> 60 #include <netinet/ip_var.h> 61 #include <netinet/icmp_var.h> 62 63 #ifdef IPSEC 64 #include <netinet6/ipsec.h> 65 #include <netproto/key/key.h> 66 #endif 67 68 #ifdef FAST_IPSEC 69 #include <netproto/ipsec/ipsec.h> 70 #include <netproto/ipsec/key.h> 71 #define IPSEC 72 #endif 73 74 /* 75 * ICMP routines: error generation, receive packet processing, and 76 * routines to turnaround packets back to the originator, and 77 * host table maintenance routines. 78 */ 79 80 struct icmpstat icmpstat; 81 SYSCTL_STRUCT(_net_inet_icmp, ICMPCTL_STATS, stats, CTLFLAG_RW, 82 &icmpstat, icmpstat, "ICMP statistics"); 83 84 static int icmpmaskrepl = 0; 85 SYSCTL_INT(_net_inet_icmp, ICMPCTL_MASKREPL, maskrepl, CTLFLAG_RW, 86 &icmpmaskrepl, 0, "Allow replies to netmask requests"); 87 88 static int drop_redirect = 0; 89 SYSCTL_INT(_net_inet_icmp, OID_AUTO, drop_redirect, CTLFLAG_RW, 90 &drop_redirect, 0, "Ignore ICMP redirects"); 91 92 static int log_redirect = 0; 93 SYSCTL_INT(_net_inet_icmp, OID_AUTO, log_redirect, CTLFLAG_RW, 94 &log_redirect, 0, "Enable output about ICMP redirects"); 95 96 static int discard_sourcequench = 1; 97 SYSCTL_INT(_net_inet_icmp, OID_AUTO, discard_sourcequench, CTLFLAG_RW, 98 &discard_sourcequench, 0, "Discard ICMP Source Quench"); 99 100 #ifdef ICMP_BANDLIM 101 102 /* 103 * ICMP error-response bandwidth limiting sysctl. If not enabled, sysctl 104 * variable content is -1 and read-only. 105 */ 106 107 static int icmplim = 200; 108 SYSCTL_INT(_net_inet_icmp, ICMPCTL_ICMPLIM, icmplim, CTLFLAG_RW, 109 &icmplim, 0, "ICMP bandwidth limit"); 110 #else 111 112 static int icmplim = -1; 113 SYSCTL_INT(_net_inet_icmp, ICMPCTL_ICMPLIM, icmplim, CTLFLAG_RD, 114 &icmplim, 0, "ICMP bandwidth limit"); 115 116 #endif 117 118 static int icmplim_output = 0; 119 SYSCTL_INT(_net_inet_icmp, OID_AUTO, icmplim_output, CTLFLAG_RW, 120 &icmplim_output, 0, "Enable output about ICMP bandwidth limits"); 121 122 /* 123 * ICMP broadcast echo sysctl 124 */ 125 126 static int icmpbmcastecho = 0; 127 SYSCTL_INT(_net_inet_icmp, OID_AUTO, bmcastecho, CTLFLAG_RW, 128 &icmpbmcastecho, 0, ""); 129 130 static char icmp_reply_src[IFNAMSIZ]; 131 SYSCTL_STRING(_net_inet_icmp, OID_AUTO, reply_src, CTLFLAG_RW, 132 icmp_reply_src, IFNAMSIZ, "icmp reply source for non-local packets."); 133 134 static int icmp_rfi; 135 SYSCTL_INT(_net_inet_icmp, OID_AUTO, reply_from_interface, CTLFLAG_RW, 136 &icmp_rfi, 0, "ICMP reply from incoming interface for " 137 "non-local packets"); 138 139 #ifdef ICMPPRINTFS 140 static int icmpprintfs = 0; 141 SYSCTL_INT(_net_inet_icmp, OID_AUTO, debug_prints, CTLFLAG_RW, 142 &icmpprintfs, 0, "extra ICMP debug prints"); 143 #endif 144 145 static void icmp_reflect (struct mbuf *); 146 static void icmp_send (struct mbuf *, struct mbuf *, struct route *); 147 148 extern struct protosw inetsw[]; 149 150 /* 151 * Generate an error packet of type error 152 * in response to bad packet ip. 153 */ 154 void 155 icmp_error(struct mbuf *n, int type, int code, n_long dest, int destmtu) 156 { 157 struct ip *oip = mtod(n, struct ip *), *nip; 158 unsigned oiplen = IP_VHL_HL(oip->ip_vhl) << 2; 159 struct icmp *icp; 160 struct mbuf *m; 161 unsigned icmplen; 162 163 #ifdef ICMPPRINTFS 164 if (icmpprintfs) 165 kprintf("icmp_error(%p, %d, %d)\n", oip, type, code); 166 #endif 167 if (type != ICMP_REDIRECT) 168 icmpstat.icps_error++; 169 /* 170 * Don't send error if the original packet was encrypted. 171 * Don't send error if not the first fragment of message. 172 * Don't error if the old packet protocol was ICMP 173 * error message, only known informational types. 174 */ 175 if (n->m_flags & M_DECRYPTED) 176 goto freeit; 177 if (oip->ip_off &~ (IP_MF|IP_DF)) 178 goto freeit; 179 if (oip->ip_p == IPPROTO_ICMP && type != ICMP_REDIRECT && 180 n->m_len >= oiplen + ICMP_MINLEN && 181 !ICMP_INFOTYPE(((struct icmp *)((caddr_t)oip + oiplen))->icmp_type)) { 182 icmpstat.icps_oldicmp++; 183 goto freeit; 184 } 185 /* Don't send error in response to a multicast or broadcast packet */ 186 if (n->m_flags & (M_BCAST|M_MCAST)) 187 goto freeit; 188 /* 189 * First, formulate icmp message 190 */ 191 m = m_gethdr(M_NOWAIT, MT_HEADER); 192 if (m == NULL) 193 goto freeit; 194 icmplen = min(oiplen + 8, oip->ip_len); 195 if (icmplen < sizeof(struct ip)) 196 panic("icmp_error: bad length"); 197 m->m_len = icmplen + ICMP_MINLEN; 198 MH_ALIGN(m, m->m_len); 199 icp = mtod(m, struct icmp *); 200 if ((u_int)type > ICMP_MAXTYPE) 201 panic("icmp_error"); 202 icmpstat.icps_outhist[type]++; 203 icp->icmp_type = type; 204 if (type == ICMP_REDIRECT) 205 icp->icmp_gwaddr.s_addr = dest; 206 else { 207 icp->icmp_void = 0; 208 /* 209 * The following assignments assume an overlay with the 210 * zeroed icmp_void field. 211 */ 212 if (type == ICMP_PARAMPROB) { 213 icp->icmp_pptr = code; 214 code = 0; 215 } else if (type == ICMP_UNREACH && 216 code == ICMP_UNREACH_NEEDFRAG && destmtu) { 217 icp->icmp_nextmtu = htons(destmtu); 218 } 219 } 220 221 icp->icmp_code = code; 222 m_copydata(n, 0, icmplen, (caddr_t)&icp->icmp_ip); 223 nip = &icp->icmp_ip; 224 225 /* 226 * Convert fields to network representation. 227 */ 228 nip->ip_len = htons(nip->ip_len); 229 nip->ip_off = htons(nip->ip_off); 230 231 /* 232 * Now, copy old ip header (without options) 233 * in front of icmp message. 234 */ 235 if (m->m_data - sizeof(struct ip) < m->m_pktdat) 236 panic("icmp len"); 237 m->m_data -= sizeof(struct ip); 238 m->m_len += sizeof(struct ip); 239 m->m_pkthdr.len = m->m_len; 240 m->m_pkthdr.rcvif = n->m_pkthdr.rcvif; 241 nip = mtod(m, struct ip *); 242 bcopy(oip, nip, sizeof(struct ip)); 243 nip->ip_len = m->m_len; 244 nip->ip_vhl = IP_VHL_BORING; 245 nip->ip_p = IPPROTO_ICMP; 246 nip->ip_tos = 0; 247 m->m_pkthdr.fw_flags |= n->m_pkthdr.fw_flags & FW_MBUF_GENERATED; 248 icmp_reflect(m); 249 250 freeit: 251 m_freem(n); 252 } 253 254 static void 255 icmp_ctlinput_done_handler(netmsg_t nmsg) 256 { 257 struct netmsg_ctlinput *msg = (struct netmsg_ctlinput *)nmsg; 258 struct mbuf *m = msg->m; 259 int hlen = msg->hlen; 260 261 rip_input(&m, &hlen, msg->proto); 262 } 263 264 static void 265 icmp_ctlinput_done(struct mbuf *m) 266 { 267 struct netmsg_ctlinput *msg = &m->m_hdr.mh_ctlmsg; 268 269 netmsg_init(&msg->base, NULL, &netisr_apanic_rport, 0, 270 icmp_ctlinput_done_handler); 271 lwkt_sendmsg(netisr_cpuport(0), &msg->base.lmsg); 272 } 273 274 static void 275 icmp_mtudisc(struct mbuf *m, int hlen) 276 { 277 struct sockaddr_in icmpsrc = { sizeof(struct sockaddr_in), AF_INET }; 278 struct rtentry *rt; 279 struct icmp *icp; 280 281 KASSERT(curthread->td_type == TD_TYPE_NETISR, ("not in netisr")); 282 283 icp = mtodoff(m, struct icmp *, hlen); 284 icmpsrc.sin_addr = icp->icmp_ip.ip_dst; 285 286 /* 287 * MTU discovery: 288 * If we got a needfrag and there is a host route to the original 289 * destination, and the MTU is not locked, then set the MTU in the 290 * route to the suggested new value (if given) and then notify as 291 * usual. The ULPs will notice that the MTU has changed and adapt 292 * accordingly. If no new MTU was suggested, then we guess a new 293 * one less than the current value. If the new MTU is unreasonably 294 * small (arbitrarily set at 296), then we reset the MTU to the 295 * interface value and enable the lock bit, indicating that we are 296 * no longer doing MTU discovery. 297 */ 298 rt = rtpurelookup((struct sockaddr *)&icmpsrc); 299 if (rt != NULL && (rt->rt_flags & RTF_HOST) && 300 !(rt->rt_rmx.rmx_locks & RTV_MTU)) { 301 #ifdef DEBUG_MTUDISC 302 char src_buf[INET_ADDRSTRLEN]; 303 #endif 304 int mtu; 305 306 mtu = ntohs(icp->icmp_nextmtu); 307 if (!mtu) 308 mtu = ip_next_mtu(rt->rt_rmx.rmx_mtu, 1); 309 #ifdef DEBUG_MTUDISC 310 kprintf("MTU for %s reduced to %d\n", 311 inet_ntop(AF_INET, &icmpsrc.sin_addr, 312 src_buf, INET_ADDRSTRLEN), mtu); 313 #endif 314 if (mtu < 296) { 315 /* rt->rt_rmx.rmx_mtu = rt->rt_ifp->if_mtu; */ 316 rt->rt_rmx.rmx_locks |= RTV_MTU; 317 } else if (rt->rt_rmx.rmx_mtu > mtu) { 318 rt->rt_rmx.rmx_mtu = mtu; 319 } 320 } 321 if (rt != NULL) 322 --rt->rt_refcnt; 323 324 /* 325 * XXX if the packet contains [IPv4 AH TCP], we can't make a 326 * notification to TCP layer. 327 */ 328 so_pr_ctlinput_direct(&inetsw[ip_protox[icp->icmp_ip.ip_p]], 329 PRC_MSGSIZE, (struct sockaddr *)&icmpsrc, &icp->icmp_ip); 330 } 331 332 static void 333 icmp_mtudisc_handler(netmsg_t nmsg) 334 { 335 struct netmsg_ctlinput *msg = (struct netmsg_ctlinput *)nmsg; 336 int nextcpu; 337 338 icmp_mtudisc(msg->m, msg->hlen); 339 340 nextcpu = mycpuid + 1; 341 if (nextcpu < ncpus) 342 lwkt_forwardmsg(netisr_cpuport(nextcpu), &msg->base.lmsg); 343 else 344 icmp_ctlinput_done(msg->m); 345 } 346 347 static boolean_t 348 icmp_mtudisc_start(struct mbuf *m, int hlen, int proto) 349 { 350 struct netmsg_ctlinput *msg; 351 352 ASSERT_IN_NETISR(0); 353 354 icmp_mtudisc(m, hlen); 355 356 if (ncpus == 1) { 357 /* There is only one netisr; done */ 358 return FALSE; 359 } 360 361 msg = &m->m_hdr.mh_ctlmsg; 362 netmsg_init(&msg->base, NULL, &netisr_apanic_rport, 0, 363 icmp_mtudisc_handler); 364 msg->m = m; 365 msg->cmd = PRC_MSGSIZE; 366 msg->hlen = hlen; 367 msg->proto = proto; 368 369 lwkt_sendmsg(netisr_cpuport(1), &msg->base.lmsg); 370 return TRUE; 371 } 372 373 static void 374 icmp_ctlinput(struct mbuf *m, int cmd, int hlen) 375 { 376 struct sockaddr_in icmpsrc = { sizeof(struct sockaddr_in), AF_INET }; 377 struct icmp *icp; 378 379 KASSERT(curthread->td_type == TD_TYPE_NETISR, ("not in netisr")); 380 381 icp = mtodoff(m, struct icmp *, hlen); 382 icmpsrc.sin_addr = icp->icmp_ip.ip_dst; 383 384 /* 385 * XXX if the packet contains [IPv4 AH TCP], we can't make a 386 * notification to TCP layer. 387 */ 388 so_pr_ctlinput_direct(&inetsw[ip_protox[icp->icmp_ip.ip_p]], 389 cmd, (struct sockaddr *)&icmpsrc, &icp->icmp_ip); 390 } 391 392 static void 393 icmp_ctlinput_handler(netmsg_t nmsg) 394 { 395 struct netmsg_ctlinput *msg = (struct netmsg_ctlinput *)nmsg; 396 397 icmp_ctlinput(msg->m, msg->cmd, msg->hlen); 398 icmp_ctlinput_done(msg->m); 399 } 400 401 static void 402 icmp_ctlinput_start(struct mbuf *m, struct lwkt_port *port, 403 int cmd, int hlen, int proto) 404 { 405 struct netmsg_ctlinput *msg; 406 407 KASSERT(&curthread->td_msgport != port, 408 ("send icmp ctlinput to the current netisr")); 409 410 msg = &m->m_hdr.mh_ctlmsg; 411 netmsg_init(&msg->base, NULL, &netisr_apanic_rport, 0, 412 icmp_ctlinput_handler); 413 msg->m = m; 414 msg->cmd = cmd; 415 msg->hlen = hlen; 416 msg->proto = proto; 417 418 lwkt_sendmsg(port, &msg->base.lmsg); 419 } 420 421 static void 422 icmp_ctlinput_global_handler(netmsg_t nmsg) 423 { 424 struct netmsg_ctlinput *msg = (struct netmsg_ctlinput *)nmsg; 425 int nextcpu; 426 427 icmp_ctlinput(msg->m, msg->cmd, msg->hlen); 428 429 nextcpu = mycpuid + 1; 430 if (nextcpu < ncpus) 431 lwkt_forwardmsg(netisr_cpuport(nextcpu), &msg->base.lmsg); 432 else 433 icmp_ctlinput_done(msg->m); 434 } 435 436 static void 437 icmp_ctlinput_global_start(struct mbuf *m, int cmd, int hlen, int proto) 438 { 439 struct netmsg_ctlinput *msg; 440 441 ASSERT_IN_NETISR(0); 442 KASSERT(ncpus > 1, ("there is only 1 cpu")); 443 444 icmp_ctlinput(m, cmd, hlen); 445 446 msg = &m->m_hdr.mh_ctlmsg; 447 netmsg_init(&msg->base, NULL, &netisr_apanic_rport, 0, 448 icmp_ctlinput_global_handler); 449 msg->m = m; 450 msg->cmd = cmd; 451 msg->hlen = hlen; 452 msg->proto = proto; 453 454 lwkt_sendmsg(netisr_cpuport(1), &msg->base.lmsg); 455 } 456 457 #define ICMP_RTREDIRECT_FLAGS (RTF_GATEWAY | RTF_HOST) 458 459 static void 460 icmp_redirect(struct mbuf *m, int hlen, boolean_t prt) 461 { 462 struct sockaddr_in icmpsrc = { sizeof(struct sockaddr_in), AF_INET }; 463 struct sockaddr_in icmpdst = { sizeof(struct sockaddr_in), AF_INET }; 464 struct sockaddr_in icmpgw = { sizeof(struct sockaddr_in), AF_INET }; 465 struct icmp *icp; 466 struct ip *ip; 467 468 KASSERT(curthread->td_type == TD_TYPE_NETISR, ("not in netisr")); 469 470 ip = mtod(m, struct ip *); 471 icp = mtodoff(m, struct icmp *, hlen); 472 473 /* 474 * Short circuit routing redirects to force immediate change 475 * in the kernel's routing tables. The message is also handed 476 * to anyone listening on a raw socket (e.g. the routing daemon 477 * for use in updating its tables). 478 */ 479 #ifdef ICMPPRINTFS 480 if (icmpprintfs && prt) { 481 char dst_buf[INET_ADDRSTRLEN], gw_buf[INET_ADDRSTRLEN]; 482 483 kprintf("redirect dst %s to %s\n", 484 inet_ntop(AF_INET, &icp->icmp_ip.ip_dst, 485 dst_buf, INET_ADDRSTRLEN), 486 inet_ntop(AF_INET, &icp->icmp_gwaddr, 487 gw_buf, INET_ADDRSTRLEN)); 488 } 489 #endif 490 icmpgw.sin_addr = ip->ip_src; 491 icmpdst.sin_addr = icp->icmp_gwaddr; 492 icmpsrc.sin_addr = icp->icmp_ip.ip_dst; 493 rtredirect_oncpu((struct sockaddr *)&icmpsrc, 494 (struct sockaddr *)&icmpdst, NULL, ICMP_RTREDIRECT_FLAGS, 495 (struct sockaddr *)&icmpgw); 496 kpfctlinput_direct(PRC_REDIRECT_HOST, (struct sockaddr *)&icmpsrc); 497 } 498 499 static void 500 icmp_redirect_done_handler(netmsg_t nmsg) 501 { 502 struct netmsg_ctlinput *msg = (struct netmsg_ctlinput *)nmsg; 503 struct mbuf *m = msg->m; 504 int hlen = msg->hlen; 505 #ifdef IPSEC 506 struct sockaddr_in icmpsrc = { sizeof(struct sockaddr_in), AF_INET }; 507 struct icmp *icp = mtodoff(m, struct icmp *, hlen);; 508 509 icmpsrc.sin_addr = icp->icmp_ip.ip_dst; 510 key_sa_routechange((struct sockaddr *)&icmpsrc); 511 #endif 512 rip_input(&m, &hlen, msg->proto); 513 } 514 515 static void 516 icmp_redirect_done(struct mbuf *m, int hlen, boolean_t dispatch_rip) 517 { 518 struct rt_addrinfo rtinfo; 519 struct sockaddr_in icmpsrc = { sizeof(struct sockaddr_in), AF_INET }; 520 struct sockaddr_in icmpdst = { sizeof(struct sockaddr_in), AF_INET }; 521 struct sockaddr_in icmpgw = { sizeof(struct sockaddr_in), AF_INET }; 522 struct icmp *icp; 523 struct ip *ip; 524 525 ip = mtod(m, struct ip *); 526 icp = mtodoff(m, struct icmp *, hlen); 527 528 icmpgw.sin_addr = ip->ip_src; 529 icmpdst.sin_addr = icp->icmp_gwaddr; 530 icmpsrc.sin_addr = icp->icmp_ip.ip_dst; 531 532 bzero(&rtinfo, sizeof(struct rt_addrinfo)); 533 rtinfo.rti_info[RTAX_DST] = (struct sockaddr *)&icmpsrc; 534 rtinfo.rti_info[RTAX_GATEWAY] = (struct sockaddr *)&icmpdst; 535 rtinfo.rti_info[RTAX_NETMASK] = NULL; 536 rtinfo.rti_info[RTAX_AUTHOR] = (struct sockaddr *)&icmpgw; 537 rt_missmsg(RTM_REDIRECT, &rtinfo, ICMP_RTREDIRECT_FLAGS, 0); 538 539 if (dispatch_rip) { 540 struct netmsg_ctlinput *msg = &m->m_hdr.mh_ctlmsg; 541 542 netmsg_init(&msg->base, NULL, &netisr_apanic_rport, 0, 543 icmp_redirect_done_handler); 544 lwkt_sendmsg(netisr_cpuport(0), &msg->base.lmsg); 545 } 546 } 547 548 static void 549 icmp_redirect_handler(netmsg_t nmsg) 550 { 551 struct netmsg_ctlinput *msg = (struct netmsg_ctlinput *)nmsg; 552 int nextcpu; 553 554 icmp_redirect(msg->m, msg->hlen, FALSE); 555 556 nextcpu = mycpuid + 1; 557 if (nextcpu < ncpus) 558 lwkt_forwardmsg(netisr_cpuport(nextcpu), &msg->base.lmsg); 559 else 560 icmp_redirect_done(msg->m, msg->hlen, TRUE); 561 } 562 563 static boolean_t 564 icmp_redirect_start(struct mbuf *m, int hlen, int proto) 565 { 566 struct netmsg_ctlinput *msg; 567 568 ASSERT_IN_NETISR(0); 569 570 icmp_redirect(m, hlen, TRUE); 571 572 if (ncpus == 1) { 573 /* There is only one netisr; done */ 574 icmp_redirect_done(m, hlen, FALSE); 575 return FALSE; 576 } 577 578 msg = &m->m_hdr.mh_ctlmsg; 579 netmsg_init(&msg->base, NULL, &netisr_apanic_rport, 0, 580 icmp_redirect_handler); 581 msg->m = m; 582 msg->cmd = PRC_REDIRECT_HOST; 583 msg->hlen = hlen; 584 msg->proto = proto; 585 586 lwkt_sendmsg(netisr_cpuport(1), &msg->base.lmsg); 587 return TRUE; 588 } 589 590 /* 591 * Process a received ICMP message. 592 */ 593 int 594 icmp_input(struct mbuf **mp, int *offp, int proto) 595 { 596 struct sockaddr_in icmpsrc = { sizeof(struct sockaddr_in), AF_INET }; 597 struct sockaddr_in icmpdst = { sizeof(struct sockaddr_in), AF_INET }; 598 struct icmp *icp; 599 struct in_ifaddr *ia; 600 struct mbuf *m = *mp; 601 struct ip *ip = mtod(m, struct ip *); 602 int icmplen = ip->ip_len; 603 int i, hlen; 604 int code; 605 606 ASSERT_IN_NETISR(0); 607 608 *mp = NULL; 609 hlen = *offp; 610 611 /* 612 * Locate icmp structure in mbuf, and check 613 * that not corrupted and of at least minimum length. 614 */ 615 #ifdef ICMPPRINTFS 616 if (icmpprintfs) { 617 char src_buf[INET_ADDRSTRLEN], dst_buf[INET_ADDRSTRLEN]; 618 619 kprintf("icmp_input from %s to %s, len %d\n", 620 inet_ntop(AF_INET, &ip->ip_src, src_buf, INET_ADDRSTRLEN), 621 inet_ntop(AF_INET, &ip->ip_dst, dst_buf, INET_ADDRSTRLEN), 622 icmplen); 623 } 624 #endif 625 if (icmplen < ICMP_MINLEN) { 626 icmpstat.icps_tooshort++; 627 goto freeit; 628 } 629 i = hlen + min(icmplen, ICMP_ADVLENMIN); 630 if (m->m_len < i && (m = m_pullup(m, i)) == NULL) { 631 icmpstat.icps_tooshort++; 632 return(IPPROTO_DONE); 633 } 634 ip = mtod(m, struct ip *); 635 636 if (in_cksum_skip(m, hlen + icmplen, hlen)) { 637 icmpstat.icps_checksum++; 638 goto freeit; 639 } 640 icp = (struct icmp *)((caddr_t)ip + hlen); 641 642 if (m->m_pkthdr.rcvif && m->m_pkthdr.rcvif->if_type == IFT_FAITH) { 643 /* 644 * Deliver very specific ICMP type only. 645 */ 646 switch (icp->icmp_type) { 647 case ICMP_UNREACH: 648 case ICMP_TIMXCEED: 649 break; 650 default: 651 goto freeit; 652 } 653 } 654 655 #ifdef ICMPPRINTFS 656 if (icmpprintfs) 657 kprintf("icmp_input, type %d code %d\n", icp->icmp_type, 658 icp->icmp_code); 659 #endif 660 661 /* 662 * Message type specific processing. 663 */ 664 if (icp->icmp_type > ICMP_MAXTYPE) 665 goto raw; 666 icmpstat.icps_inhist[icp->icmp_type]++; 667 code = icp->icmp_code; 668 switch (icp->icmp_type) { 669 670 case ICMP_UNREACH: 671 switch (code) { 672 case ICMP_UNREACH_NET: 673 case ICMP_UNREACH_HOST: 674 case ICMP_UNREACH_SRCFAIL: 675 case ICMP_UNREACH_NET_UNKNOWN: 676 case ICMP_UNREACH_HOST_UNKNOWN: 677 case ICMP_UNREACH_ISOLATED: 678 case ICMP_UNREACH_TOSNET: 679 case ICMP_UNREACH_TOSHOST: 680 case ICMP_UNREACH_HOST_PRECEDENCE: 681 case ICMP_UNREACH_PRECEDENCE_CUTOFF: 682 code = PRC_UNREACH_NET; 683 break; 684 685 case ICMP_UNREACH_NEEDFRAG: 686 code = PRC_MSGSIZE; 687 break; 688 689 /* 690 * RFC 1122, Sections 3.2.2.1 and 4.2.3.9. 691 * Treat subcodes 2,3 as immediate RST 692 */ 693 case ICMP_UNREACH_PROTOCOL: 694 case ICMP_UNREACH_PORT: 695 code = PRC_UNREACH_PORT; 696 break; 697 698 case ICMP_UNREACH_NET_PROHIB: 699 case ICMP_UNREACH_HOST_PROHIB: 700 case ICMP_UNREACH_FILTER_PROHIB: 701 code = PRC_UNREACH_ADMIN_PROHIB; 702 break; 703 704 default: 705 goto badcode; 706 } 707 goto deliver; 708 709 case ICMP_TIMXCEED: 710 if (code > 1) 711 goto badcode; 712 code += PRC_TIMXCEED_INTRANS; 713 goto deliver; 714 715 case ICMP_PARAMPROB: 716 if (code > 1) 717 goto badcode; 718 code = PRC_PARAMPROB; 719 goto deliver; 720 721 case ICMP_SOURCEQUENCH: 722 if (code) 723 goto badcode; 724 if (discard_sourcequench) 725 break; 726 code = PRC_QUENCH; 727 deliver: 728 /* 729 * Problem with datagram; advise higher level routines. 730 */ 731 if (icmplen < ICMP_ADVLENMIN || icmplen < ICMP_ADVLEN(icp) || 732 IP_VHL_HL(icp->icmp_ip.ip_vhl) < (sizeof(struct ip) >> 2)) { 733 icmpstat.icps_badlen++; 734 goto freeit; 735 } 736 /* Discard ICMP's in response to multicast packets */ 737 if (IN_MULTICAST(ntohl(icp->icmp_ip.ip_dst.s_addr))) 738 goto badcode; 739 #ifdef ICMPPRINTFS 740 if (icmpprintfs) 741 kprintf("deliver to protocol %d\n", icp->icmp_ip.ip_p); 742 #endif 743 icmpsrc.sin_addr = icp->icmp_ip.ip_dst; 744 745 /* 746 * MTU discovery 747 */ 748 if (code == PRC_MSGSIZE) { 749 /* Run MTU discovery in all netisrs */ 750 if (icmp_mtudisc_start(m, hlen, proto)) { 751 /* Forwarded; done */ 752 return IPPROTO_DONE; 753 } 754 /* Move on; run rip_input() directly */ 755 } else { 756 struct protosw *pr; 757 struct lwkt_port *port; 758 int cpu; 759 760 pr = &inetsw[ip_protox[icp->icmp_ip.ip_p]]; 761 port = so_pr_ctlport(pr, code, 762 (struct sockaddr *)&icmpsrc, &icp->icmp_ip, &cpu); 763 if (port != NULL) { 764 if (cpu == ncpus) { 765 if (ncpus > 1) { 766 /* 767 * Run pr_ctlinput in all 768 * netisrs 769 */ 770 icmp_ctlinput_global_start(m, 771 code, hlen, proto); 772 return IPPROTO_DONE; 773 } 774 /* 775 * There is only one netisr; run 776 * pr_ctlinput directly. 777 */ 778 } else if (cpu != mycpuid) { 779 /* 780 * Send to the target netisr to run 781 * pr_ctlinput. 782 */ 783 icmp_ctlinput_start(m, port, 784 code, hlen, proto); 785 return IPPROTO_DONE; 786 } 787 788 /* 789 * The target netisr is this netisr. 790 * 791 * XXX if the packet contains [IPv4 AH TCP], 792 * we can't make a notification to TCP layer. 793 */ 794 so_pr_ctlinput_direct(pr, code, 795 (struct sockaddr *)&icmpsrc, &icp->icmp_ip); 796 } 797 /* Move on; run rip_input() directly */ 798 } 799 break; 800 badcode: 801 icmpstat.icps_badcode++; 802 break; 803 804 case ICMP_ECHO: 805 if (!icmpbmcastecho 806 && (m->m_flags & (M_MCAST | M_BCAST)) != 0) { 807 icmpstat.icps_bmcastecho++; 808 break; 809 } 810 icp->icmp_type = ICMP_ECHOREPLY; 811 #ifdef ICMP_BANDLIM 812 if (badport_bandlim(BANDLIM_ICMP_ECHO) < 0) 813 goto freeit; 814 else 815 #endif 816 goto reflect; 817 818 case ICMP_TSTAMP: 819 if (!icmpbmcastecho 820 && (m->m_flags & (M_MCAST | M_BCAST)) != 0) { 821 icmpstat.icps_bmcasttstamp++; 822 break; 823 } 824 if (icmplen < ICMP_TSLEN) { 825 icmpstat.icps_badlen++; 826 break; 827 } 828 icp->icmp_type = ICMP_TSTAMPREPLY; 829 icp->icmp_rtime = iptime(); 830 icp->icmp_ttime = icp->icmp_rtime; /* bogus, do later! */ 831 #ifdef ICMP_BANDLIM 832 if (badport_bandlim(BANDLIM_ICMP_TSTAMP) < 0) 833 goto freeit; 834 else 835 #endif 836 goto reflect; 837 838 case ICMP_MASKREQ: 839 if (icmpmaskrepl == 0) 840 break; 841 /* 842 * We are not able to respond with all ones broadcast 843 * unless we receive it over a point-to-point interface. 844 */ 845 if (icmplen < ICMP_MASKLEN) 846 break; 847 switch (ip->ip_dst.s_addr) { 848 849 case INADDR_BROADCAST: 850 case INADDR_ANY: 851 icmpdst.sin_addr = ip->ip_src; 852 break; 853 854 default: 855 icmpdst.sin_addr = ip->ip_dst; 856 } 857 ia = (struct in_ifaddr *)ifaof_ifpforaddr( 858 (struct sockaddr *)&icmpdst, m->m_pkthdr.rcvif); 859 if (ia == NULL) 860 break; 861 if (ia->ia_ifp == 0) 862 break; 863 icp->icmp_type = ICMP_MASKREPLY; 864 icp->icmp_mask = ia->ia_sockmask.sin_addr.s_addr; 865 if (ip->ip_src.s_addr == 0) { 866 if (ia->ia_ifp->if_flags & IFF_BROADCAST) 867 ip->ip_src = satosin(&ia->ia_broadaddr)->sin_addr; 868 else if (ia->ia_ifp->if_flags & IFF_POINTOPOINT) 869 ip->ip_src = satosin(&ia->ia_dstaddr)->sin_addr; 870 } 871 reflect: 872 ip->ip_len += hlen; /* since ip_input deducts this */ 873 icmpstat.icps_reflect++; 874 icmpstat.icps_outhist[icp->icmp_type]++; 875 icmp_reflect(m); 876 return(IPPROTO_DONE); 877 878 case ICMP_REDIRECT: 879 if (log_redirect) { 880 char src_buf[INET_ADDRSTRLEN]; 881 char dst_buf[INET_ADDRSTRLEN]; 882 char gwy_buf[INET_ADDRSTRLEN]; 883 884 kprintf("icmp redirect from %s: %s => %s\n", 885 inet_ntop(AF_INET, &ip->ip_src, 886 src_buf, INET_ADDRSTRLEN), 887 inet_ntop(AF_INET, &icp->icmp_ip.ip_dst, 888 dst_buf, INET_ADDRSTRLEN), 889 inet_ntop(AF_INET, &icp->icmp_gwaddr, 890 gwy_buf, INET_ADDRSTRLEN)); 891 } 892 if (drop_redirect) 893 break; 894 if (code > 3) 895 goto badcode; 896 if (icmplen < ICMP_ADVLENMIN || icmplen < ICMP_ADVLEN(icp) || 897 IP_VHL_HL(icp->icmp_ip.ip_vhl) < (sizeof(struct ip) >> 2)) { 898 icmpstat.icps_badlen++; 899 break; 900 } 901 #ifdef ICMPPRINTFS 902 if (icmpprintfs) { 903 char dst_buf[INET_ADDRSTRLEN], gw_buf[INET_ADDRSTRLEN]; 904 905 kprintf("redirect dst %s to %s\n", 906 inet_ntop(AF_INET, &icp->icmp_ip.ip_dst, 907 dst_buf, INET_ADDRSTRLEN), 908 inet_ntop(AF_INET, &icp->icmp_gwaddr, 909 gw_buf, INET_ADDRSTRLEN)); 910 } 911 #endif 912 icmpsrc.sin_addr = icp->icmp_ip.ip_dst; 913 914 /* Run redirect in all netisrs */ 915 if (icmp_redirect_start(m, hlen, proto)) { 916 /* Forwarded; done */ 917 return IPPROTO_DONE; 918 } 919 /* Move on; run rip_input() directly */ 920 #ifdef IPSEC 921 key_sa_routechange((struct sockaddr *)&icmpsrc); 922 #endif 923 break; 924 925 /* 926 * No kernel processing for the following; 927 * just fall through to send to raw listener. 928 */ 929 case ICMP_ECHOREPLY: 930 case ICMP_ROUTERADVERT: 931 case ICMP_ROUTERSOLICIT: 932 case ICMP_TSTAMPREPLY: 933 case ICMP_IREQREPLY: 934 case ICMP_MASKREPLY: 935 default: 936 break; 937 } 938 939 raw: 940 *mp = m; 941 rip_input(mp, offp, proto); 942 return(IPPROTO_DONE); 943 944 freeit: 945 m_freem(m); 946 return(IPPROTO_DONE); 947 } 948 949 /* 950 * Reflect the ip packet back to the source 951 */ 952 static void 953 icmp_reflect(struct mbuf *m) 954 { 955 struct ip *ip = mtod(m, struct ip *); 956 struct in_ifaddr *ia; 957 struct in_ifaddr_container *iac; 958 struct ifaddr_container *ifac; 959 struct ifnet *ifp; 960 struct in_addr t; 961 struct mbuf *opts = NULL; 962 int optlen = (IP_VHL_HL(ip->ip_vhl) << 2) - sizeof(struct ip); 963 struct route *ro = NULL, rt; 964 965 if (!in_canforward(ip->ip_src) && 966 ((ntohl(ip->ip_src.s_addr) & IN_CLASSA_NET) != 967 (IN_LOOPBACKNET << IN_CLASSA_NSHIFT))) { 968 m_freem(m); /* Bad return address */ 969 icmpstat.icps_badaddr++; 970 goto done; /* Ip_output() will check for broadcast */ 971 } 972 t = ip->ip_dst; 973 ip->ip_dst = ip->ip_src; 974 975 ro = &rt; 976 bzero(ro, sizeof *ro); 977 978 /* 979 * If the incoming packet was addressed directly to us, 980 * use dst as the src for the reply. Otherwise (broadcast 981 * or anonymous), use the address which corresponds 982 * to the incoming interface. 983 */ 984 ia = NULL; 985 LIST_FOREACH(iac, INADDR_HASH(t.s_addr), ia_hash) { 986 if (t.s_addr == IA_SIN(iac->ia)->sin_addr.s_addr) { 987 ia = iac->ia; 988 goto match; 989 } 990 } 991 ifp = m->m_pkthdr.rcvif; 992 if (ifp != NULL && (ifp->if_flags & IFF_BROADCAST)) { 993 TAILQ_FOREACH(ifac, &ifp->if_addrheads[mycpuid], ifa_link) { 994 struct ifaddr *ifa = ifac->ifa; 995 996 if (ifa->ifa_addr->sa_family != AF_INET) 997 continue; 998 ia = ifatoia(ifa); 999 if (satosin(&ia->ia_broadaddr)->sin_addr.s_addr == 1000 t.s_addr) 1001 goto match; 1002 } 1003 } 1004 /* 1005 * If the packet was transiting through us, use the address of 1006 * the interface the packet came through in. If that interface 1007 * doesn't have a suitable IP address, the normal selection 1008 * criteria apply. 1009 */ 1010 if (icmp_rfi && ifp != NULL) { 1011 TAILQ_FOREACH(ifac, &ifp->if_addrheads[mycpuid], ifa_link) { 1012 struct ifaddr *ifa = ifac->ifa; 1013 1014 if (ifa->ifa_addr->sa_family != AF_INET) 1015 continue; 1016 ia = ifatoia(ifa); 1017 goto match; 1018 } 1019 } 1020 /* 1021 * If the incoming packet was not addressed directly to us, use 1022 * designated interface for icmp replies specified by sysctl 1023 * net.inet.icmp.reply_src (default not set). Otherwise continue 1024 * with normal source selection. 1025 */ 1026 if (icmp_reply_src[0] != '\0' && 1027 (ifp = ifunit_netisr(icmp_reply_src))) { 1028 TAILQ_FOREACH(ifac, &ifp->if_addrheads[mycpuid], ifa_link) { 1029 struct ifaddr *ifa = ifac->ifa; 1030 1031 if (ifa->ifa_addr->sa_family != AF_INET) 1032 continue; 1033 ia = ifatoia(ifa); 1034 goto match; 1035 } 1036 } 1037 /* 1038 * If the packet was transiting through us, use the address of 1039 * the interface that is the closest to the packet source. 1040 * When we don't have a route back to the packet source, stop here 1041 * and drop the packet. 1042 */ 1043 ia = ip_rtaddr(ip->ip_dst, ro); 1044 if (ia == NULL) { 1045 m_freem(m); 1046 icmpstat.icps_noroute++; 1047 goto done; 1048 } 1049 match: 1050 t = IA_SIN(ia)->sin_addr; 1051 ip->ip_src = t; 1052 ip->ip_ttl = ip_defttl; 1053 1054 if (optlen > 0) { 1055 u_char *cp; 1056 int opt, cnt; 1057 u_int len; 1058 1059 /* 1060 * Retrieve any source routing from the incoming packet; 1061 * add on any record-route or timestamp options. 1062 */ 1063 cp = (u_char *) (ip + 1); 1064 if ((opts = ip_srcroute(m)) == NULL && 1065 (opts = m_gethdr(M_NOWAIT, MT_HEADER))) { 1066 opts->m_len = sizeof(struct in_addr); 1067 mtod(opts, struct in_addr *)->s_addr = 0; 1068 } 1069 if (opts) { 1070 #ifdef ICMPPRINTFS 1071 if (icmpprintfs) 1072 kprintf("icmp_reflect optlen %d rt %d => ", 1073 optlen, opts->m_len); 1074 #endif 1075 for (cnt = optlen; cnt > 0; cnt -= len, cp += len) { 1076 opt = cp[IPOPT_OPTVAL]; 1077 if (opt == IPOPT_EOL) 1078 break; 1079 if (opt == IPOPT_NOP) 1080 len = 1; 1081 else { 1082 if (cnt < IPOPT_OLEN + sizeof *cp) 1083 break; 1084 len = cp[IPOPT_OLEN]; 1085 if (len < IPOPT_OLEN + sizeof *cp || 1086 len > cnt) 1087 break; 1088 } 1089 /* 1090 * Should check for overflow, but it 1091 * "can't happen". 1092 */ 1093 if (opt == IPOPT_RR || opt == IPOPT_TS || 1094 opt == IPOPT_SECURITY) { 1095 bcopy(cp, 1096 mtod(opts, caddr_t) + opts->m_len, 1097 len); 1098 opts->m_len += len; 1099 } 1100 } 1101 /* Terminate & pad, if necessary */ 1102 cnt = opts->m_len % 4; 1103 if (cnt) { 1104 for (; cnt < 4; cnt++) { 1105 *(mtod(opts, caddr_t) + opts->m_len) = 1106 IPOPT_EOL; 1107 opts->m_len++; 1108 } 1109 } 1110 #ifdef ICMPPRINTFS 1111 if (icmpprintfs) 1112 kprintf("%d\n", opts->m_len); 1113 #endif 1114 } 1115 /* 1116 * Now strip out original options by copying rest of first 1117 * mbuf's data back, and adjust the IP length. 1118 */ 1119 ip->ip_len -= optlen; 1120 ip->ip_vhl = IP_VHL_BORING; 1121 m->m_len -= optlen; 1122 if (m->m_flags & M_PKTHDR) 1123 m->m_pkthdr.len -= optlen; 1124 optlen += sizeof(struct ip); 1125 bcopy((caddr_t)ip + optlen, ip + 1, 1126 m->m_len - sizeof(struct ip)); 1127 } 1128 m->m_pkthdr.fw_flags &= FW_MBUF_GENERATED; 1129 m->m_flags &= ~(M_BCAST|M_MCAST); 1130 icmp_send(m, opts, ro); 1131 done: 1132 if (opts) 1133 m_free(opts); 1134 if (ro && ro->ro_rt) 1135 RTFREE(ro->ro_rt); 1136 } 1137 1138 /* 1139 * Send an icmp packet back to the ip level, 1140 * after supplying a checksum. 1141 */ 1142 static void 1143 icmp_send(struct mbuf *m, struct mbuf *opts, struct route *rt) 1144 { 1145 struct ip *ip = mtod(m, struct ip *); 1146 struct icmp *icp; 1147 int hlen; 1148 1149 hlen = IP_VHL_HL(ip->ip_vhl) << 2; 1150 m->m_data += hlen; 1151 m->m_len -= hlen; 1152 icp = mtod(m, struct icmp *); 1153 icp->icmp_cksum = 0; 1154 icp->icmp_cksum = in_cksum(m, ip->ip_len - hlen); 1155 m->m_data -= hlen; 1156 m->m_len += hlen; 1157 m->m_pkthdr.rcvif = NULL; 1158 #ifdef ICMPPRINTFS 1159 if (icmpprintfs) { 1160 char dst_buf[INET_ADDRSTRLEN], src_buf[INET_ADDRSTRLEN]; 1161 1162 kprintf("icmp_send dst %s src %s\n", 1163 inet_ntop(AF_INET, &ip->ip_dst, dst_buf, INET_ADDRSTRLEN), 1164 inet_ntop(AF_INET, &ip->ip_src, src_buf, INET_ADDRSTRLEN)); 1165 } 1166 #endif 1167 ip_output(m, opts, rt, 0, NULL, NULL); 1168 } 1169 1170 n_time 1171 iptime(void) 1172 { 1173 struct timeval atv; 1174 u_long t; 1175 1176 getmicrotime(&atv); 1177 t = (atv.tv_sec % (24*60*60)) * 1000 + atv.tv_usec / 1000; 1178 return (htonl(t)); 1179 } 1180 1181 #if 1 1182 /* 1183 * Return the next larger or smaller MTU plateau (table from RFC 1191) 1184 * given current value MTU. If DIR is less than zero, a larger plateau 1185 * is returned; otherwise, a smaller value is returned. 1186 */ 1187 int 1188 ip_next_mtu(int mtu, int dir) 1189 { 1190 static int mtutab[] = { 1191 65535, 32000, 17914, 8166, 4352, 2002, 1492, 1006, 508, 296, 1192 68, 0 1193 }; 1194 int i; 1195 1196 for (i = 0; i < (sizeof mtutab) / (sizeof mtutab[0]); i++) { 1197 if (mtu >= mtutab[i]) 1198 break; 1199 } 1200 1201 if (dir < 0) { 1202 if (i == 0) { 1203 return 0; 1204 } else { 1205 return mtutab[i - 1]; 1206 } 1207 } else { 1208 if (mtutab[i] == 0) { 1209 return 0; 1210 } else if(mtu > mtutab[i]) { 1211 return mtutab[i]; 1212 } else { 1213 return mtutab[i + 1]; 1214 } 1215 } 1216 } 1217 #endif 1218 1219 #ifdef ICMP_BANDLIM 1220 /* 1221 * badport_bandlim() - check for ICMP bandwidth limit 1222 * 1223 * Return 0 if it is ok to send an ICMP error response, -1 if we have 1224 * hit our bandwidth limit and it is not ok. 1225 * 1226 * If icmplim is <= 0, the feature is disabled and 0 is returned. 1227 * 1228 * For now we separate the TCP and UDP subsystems w/ different 'which' 1229 * values. We may eventually remove this separation (and simplify the 1230 * code further). 1231 * 1232 * Note that the printing of the error message is delayed so we can 1233 * properly print the icmp error rate that the system was trying to do 1234 * (i.e. 22000/100 pps, etc...). This can cause long delays in printing 1235 * the 'final' error, but it doesn't make sense to solve the printing 1236 * delay with more complex code. 1237 */ 1238 int 1239 badport_bandlim(int which) 1240 { 1241 static int lticks[BANDLIM_MAX + 1]; 1242 static int lpackets[BANDLIM_MAX + 1]; 1243 int dticks; 1244 const char *bandlimittype[] = { 1245 "Limiting icmp unreach response", 1246 "Limiting icmp ping response", 1247 "Limiting icmp tstamp response", 1248 "Limiting closed port RST response", 1249 "Limiting open port RST response" 1250 }; 1251 1252 /* 1253 * Return ok status if feature disabled or argument out of 1254 * ranage. 1255 */ 1256 1257 if (icmplim <= 0 || which > BANDLIM_MAX || which < 0) 1258 return(0); 1259 dticks = ticks - lticks[which]; 1260 1261 /* 1262 * reset stats when cumulative dt exceeds one second. 1263 */ 1264 1265 if ((unsigned int)dticks > hz) { 1266 if (lpackets[which] > icmplim && icmplim_output) { 1267 kprintf("%s from %d to %d packets per second\n", 1268 bandlimittype[which], 1269 lpackets[which], 1270 icmplim 1271 ); 1272 } 1273 lticks[which] = ticks; 1274 lpackets[which] = 0; 1275 } 1276 1277 /* 1278 * bump packet count 1279 */ 1280 1281 if (++lpackets[which] > icmplim) { 1282 return(-1); 1283 } 1284 return(0); 1285 } 1286 #endif 1287