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 KASSERT(&curthread->td_msgport == netisr_cpuport(0), 353 ("not in netisr0")); 354 355 icmp_mtudisc(m, hlen); 356 357 if (ncpus == 1) { 358 /* There is only one netisr; done */ 359 return FALSE; 360 } 361 362 msg = &m->m_hdr.mh_ctlmsg; 363 netmsg_init(&msg->base, NULL, &netisr_apanic_rport, 0, 364 icmp_mtudisc_handler); 365 msg->m = m; 366 msg->cmd = PRC_MSGSIZE; 367 msg->hlen = hlen; 368 msg->proto = proto; 369 370 lwkt_sendmsg(netisr_cpuport(1), &msg->base.lmsg); 371 return TRUE; 372 } 373 374 static void 375 icmp_ctlinput(struct mbuf *m, int cmd, int hlen) 376 { 377 struct sockaddr_in icmpsrc = { sizeof(struct sockaddr_in), AF_INET }; 378 struct icmp *icp; 379 380 KASSERT(curthread->td_type == TD_TYPE_NETISR, ("not in netisr")); 381 382 icp = mtodoff(m, struct icmp *, hlen); 383 icmpsrc.sin_addr = icp->icmp_ip.ip_dst; 384 385 /* 386 * XXX if the packet contains [IPv4 AH TCP], we can't make a 387 * notification to TCP layer. 388 */ 389 so_pr_ctlinput_direct(&inetsw[ip_protox[icp->icmp_ip.ip_p]], 390 cmd, (struct sockaddr *)&icmpsrc, &icp->icmp_ip); 391 } 392 393 static void 394 icmp_ctlinput_handler(netmsg_t nmsg) 395 { 396 struct netmsg_ctlinput *msg = (struct netmsg_ctlinput *)nmsg; 397 398 icmp_ctlinput(msg->m, msg->cmd, msg->hlen); 399 icmp_ctlinput_done(msg->m); 400 } 401 402 static void 403 icmp_ctlinput_start(struct mbuf *m, struct lwkt_port *port, 404 int cmd, int hlen, int proto) 405 { 406 struct netmsg_ctlinput *msg; 407 408 KASSERT(&curthread->td_msgport != port, 409 ("send icmp ctlinput to the current netisr")); 410 411 msg = &m->m_hdr.mh_ctlmsg; 412 netmsg_init(&msg->base, NULL, &netisr_apanic_rport, 0, 413 icmp_ctlinput_handler); 414 msg->m = m; 415 msg->cmd = cmd; 416 msg->hlen = hlen; 417 msg->proto = proto; 418 419 lwkt_sendmsg(port, &msg->base.lmsg); 420 } 421 422 static void 423 icmp_ctlinput_global_handler(netmsg_t nmsg) 424 { 425 struct netmsg_ctlinput *msg = (struct netmsg_ctlinput *)nmsg; 426 int nextcpu; 427 428 icmp_ctlinput(msg->m, msg->cmd, msg->hlen); 429 430 nextcpu = mycpuid + 1; 431 if (nextcpu < ncpus) 432 lwkt_forwardmsg(netisr_cpuport(nextcpu), &msg->base.lmsg); 433 else 434 icmp_ctlinput_done(msg->m); 435 } 436 437 static void 438 icmp_ctlinput_global_start(struct mbuf *m, int cmd, int hlen, int proto) 439 { 440 struct netmsg_ctlinput *msg; 441 442 KASSERT(&curthread->td_msgport == netisr_cpuport(0), 443 ("not in netisr0")); 444 KASSERT(ncpus > 1, ("there is only 1 cpu")); 445 446 icmp_ctlinput(m, cmd, hlen); 447 448 msg = &m->m_hdr.mh_ctlmsg; 449 netmsg_init(&msg->base, NULL, &netisr_apanic_rport, 0, 450 icmp_ctlinput_global_handler); 451 msg->m = m; 452 msg->cmd = cmd; 453 msg->hlen = hlen; 454 msg->proto = proto; 455 456 lwkt_sendmsg(netisr_cpuport(1), &msg->base.lmsg); 457 } 458 459 #define ICMP_RTREDIRECT_FLAGS (RTF_GATEWAY | RTF_HOST) 460 461 static void 462 icmp_redirect(struct mbuf *m, int hlen, boolean_t prt) 463 { 464 struct sockaddr_in icmpsrc = { sizeof(struct sockaddr_in), AF_INET }; 465 struct sockaddr_in icmpdst = { sizeof(struct sockaddr_in), AF_INET }; 466 struct sockaddr_in icmpgw = { sizeof(struct sockaddr_in), AF_INET }; 467 struct icmp *icp; 468 struct ip *ip; 469 470 KASSERT(curthread->td_type == TD_TYPE_NETISR, ("not in netisr")); 471 472 ip = mtod(m, struct ip *); 473 icp = mtodoff(m, struct icmp *, hlen); 474 475 /* 476 * Short circuit routing redirects to force immediate change 477 * in the kernel's routing tables. The message is also handed 478 * to anyone listening on a raw socket (e.g. the routing daemon 479 * for use in updating its tables). 480 */ 481 #ifdef ICMPPRINTFS 482 if (icmpprintfs && prt) { 483 char dst_buf[INET_ADDRSTRLEN], gw_buf[INET_ADDRSTRLEN]; 484 485 kprintf("redirect dst %s to %s\n", 486 inet_ntop(AF_INET, &icp->icmp_ip.ip_dst, 487 dst_buf, INET_ADDRSTRLEN), 488 inet_ntop(AF_INET, &icp->icmp_gwaddr, 489 gw_buf, INET_ADDRSTRLEN)); 490 } 491 #endif 492 icmpgw.sin_addr = ip->ip_src; 493 icmpdst.sin_addr = icp->icmp_gwaddr; 494 icmpsrc.sin_addr = icp->icmp_ip.ip_dst; 495 rtredirect_oncpu((struct sockaddr *)&icmpsrc, 496 (struct sockaddr *)&icmpdst, NULL, ICMP_RTREDIRECT_FLAGS, 497 (struct sockaddr *)&icmpgw); 498 kpfctlinput_direct(PRC_REDIRECT_HOST, (struct sockaddr *)&icmpsrc); 499 } 500 501 static void 502 icmp_redirect_done_handler(netmsg_t nmsg) 503 { 504 struct netmsg_ctlinput *msg = (struct netmsg_ctlinput *)nmsg; 505 struct mbuf *m = msg->m; 506 int hlen = msg->hlen; 507 #ifdef IPSEC 508 struct sockaddr_in icmpsrc = { sizeof(struct sockaddr_in), AF_INET }; 509 struct icmp *icp = mtodoff(m, struct icmp *, hlen);; 510 511 icmpsrc.sin_addr = icp->icmp_ip.ip_dst; 512 key_sa_routechange((struct sockaddr *)&icmpsrc); 513 #endif 514 rip_input(&m, &hlen, msg->proto); 515 } 516 517 static void 518 icmp_redirect_done(struct mbuf *m, int hlen, boolean_t dispatch_rip) 519 { 520 struct rt_addrinfo rtinfo; 521 struct sockaddr_in icmpsrc = { sizeof(struct sockaddr_in), AF_INET }; 522 struct sockaddr_in icmpdst = { sizeof(struct sockaddr_in), AF_INET }; 523 struct sockaddr_in icmpgw = { sizeof(struct sockaddr_in), AF_INET }; 524 struct icmp *icp; 525 struct ip *ip; 526 527 ip = mtod(m, struct ip *); 528 icp = mtodoff(m, struct icmp *, hlen); 529 530 icmpgw.sin_addr = ip->ip_src; 531 icmpdst.sin_addr = icp->icmp_gwaddr; 532 icmpsrc.sin_addr = icp->icmp_ip.ip_dst; 533 534 bzero(&rtinfo, sizeof(struct rt_addrinfo)); 535 rtinfo.rti_info[RTAX_DST] = (struct sockaddr *)&icmpsrc; 536 rtinfo.rti_info[RTAX_GATEWAY] = (struct sockaddr *)&icmpdst; 537 rtinfo.rti_info[RTAX_NETMASK] = NULL; 538 rtinfo.rti_info[RTAX_AUTHOR] = (struct sockaddr *)&icmpgw; 539 rt_missmsg(RTM_REDIRECT, &rtinfo, ICMP_RTREDIRECT_FLAGS, 0); 540 541 if (dispatch_rip) { 542 struct netmsg_ctlinput *msg = &m->m_hdr.mh_ctlmsg; 543 544 netmsg_init(&msg->base, NULL, &netisr_apanic_rport, 0, 545 icmp_redirect_done_handler); 546 lwkt_sendmsg(netisr_cpuport(0), &msg->base.lmsg); 547 } 548 } 549 550 static void 551 icmp_redirect_handler(netmsg_t nmsg) 552 { 553 struct netmsg_ctlinput *msg = (struct netmsg_ctlinput *)nmsg; 554 int nextcpu; 555 556 icmp_redirect(msg->m, msg->hlen, FALSE); 557 558 nextcpu = mycpuid + 1; 559 if (nextcpu < ncpus) 560 lwkt_forwardmsg(netisr_cpuport(nextcpu), &msg->base.lmsg); 561 else 562 icmp_redirect_done(msg->m, msg->hlen, TRUE); 563 } 564 565 static boolean_t 566 icmp_redirect_start(struct mbuf *m, int hlen, int proto) 567 { 568 struct netmsg_ctlinput *msg; 569 570 KASSERT(&curthread->td_msgport == netisr_cpuport(0), 571 ("not in netisr0")); 572 573 icmp_redirect(m, hlen, TRUE); 574 575 if (ncpus == 1) { 576 /* There is only one netisr; done */ 577 icmp_redirect_done(m, hlen, FALSE); 578 return FALSE; 579 } 580 581 msg = &m->m_hdr.mh_ctlmsg; 582 netmsg_init(&msg->base, NULL, &netisr_apanic_rport, 0, 583 icmp_redirect_handler); 584 msg->m = m; 585 msg->cmd = PRC_REDIRECT_HOST; 586 msg->hlen = hlen; 587 msg->proto = proto; 588 589 lwkt_sendmsg(netisr_cpuport(1), &msg->base.lmsg); 590 return TRUE; 591 } 592 593 /* 594 * Process a received ICMP message. 595 */ 596 int 597 icmp_input(struct mbuf **mp, int *offp, int proto) 598 { 599 struct sockaddr_in icmpsrc = { sizeof(struct sockaddr_in), AF_INET }; 600 struct sockaddr_in icmpdst = { sizeof(struct sockaddr_in), AF_INET }; 601 struct icmp *icp; 602 struct in_ifaddr *ia; 603 struct mbuf *m = *mp; 604 struct ip *ip = mtod(m, struct ip *); 605 int icmplen = ip->ip_len; 606 int i, hlen; 607 int code; 608 609 KASSERT(&curthread->td_msgport == netisr_cpuport(0), 610 ("not in netisr0")); 611 612 *mp = NULL; 613 hlen = *offp; 614 615 /* 616 * Locate icmp structure in mbuf, and check 617 * that not corrupted and of at least minimum length. 618 */ 619 #ifdef ICMPPRINTFS 620 if (icmpprintfs) { 621 char src_buf[INET_ADDRSTRLEN], dst_buf[INET_ADDRSTRLEN]; 622 623 kprintf("icmp_input from %s to %s, len %d\n", 624 inet_ntop(AF_INET, &ip->ip_src, src_buf, INET_ADDRSTRLEN), 625 inet_ntop(AF_INET, &ip->ip_dst, dst_buf, INET_ADDRSTRLEN), 626 icmplen); 627 } 628 #endif 629 if (icmplen < ICMP_MINLEN) { 630 icmpstat.icps_tooshort++; 631 goto freeit; 632 } 633 i = hlen + min(icmplen, ICMP_ADVLENMIN); 634 if (m->m_len < i && (m = m_pullup(m, i)) == NULL) { 635 icmpstat.icps_tooshort++; 636 return(IPPROTO_DONE); 637 } 638 ip = mtod(m, struct ip *); 639 640 if (in_cksum_skip(m, hlen + icmplen, hlen)) { 641 icmpstat.icps_checksum++; 642 goto freeit; 643 } 644 icp = (struct icmp *)((caddr_t)ip + hlen); 645 646 if (m->m_pkthdr.rcvif && m->m_pkthdr.rcvif->if_type == IFT_FAITH) { 647 /* 648 * Deliver very specific ICMP type only. 649 */ 650 switch (icp->icmp_type) { 651 case ICMP_UNREACH: 652 case ICMP_TIMXCEED: 653 break; 654 default: 655 goto freeit; 656 } 657 } 658 659 #ifdef ICMPPRINTFS 660 if (icmpprintfs) 661 kprintf("icmp_input, type %d code %d\n", icp->icmp_type, 662 icp->icmp_code); 663 #endif 664 665 /* 666 * Message type specific processing. 667 */ 668 if (icp->icmp_type > ICMP_MAXTYPE) 669 goto raw; 670 icmpstat.icps_inhist[icp->icmp_type]++; 671 code = icp->icmp_code; 672 switch (icp->icmp_type) { 673 674 case ICMP_UNREACH: 675 switch (code) { 676 case ICMP_UNREACH_NET: 677 case ICMP_UNREACH_HOST: 678 case ICMP_UNREACH_SRCFAIL: 679 case ICMP_UNREACH_NET_UNKNOWN: 680 case ICMP_UNREACH_HOST_UNKNOWN: 681 case ICMP_UNREACH_ISOLATED: 682 case ICMP_UNREACH_TOSNET: 683 case ICMP_UNREACH_TOSHOST: 684 case ICMP_UNREACH_HOST_PRECEDENCE: 685 case ICMP_UNREACH_PRECEDENCE_CUTOFF: 686 code = PRC_UNREACH_NET; 687 break; 688 689 case ICMP_UNREACH_NEEDFRAG: 690 code = PRC_MSGSIZE; 691 break; 692 693 /* 694 * RFC 1122, Sections 3.2.2.1 and 4.2.3.9. 695 * Treat subcodes 2,3 as immediate RST 696 */ 697 case ICMP_UNREACH_PROTOCOL: 698 case ICMP_UNREACH_PORT: 699 code = PRC_UNREACH_PORT; 700 break; 701 702 case ICMP_UNREACH_NET_PROHIB: 703 case ICMP_UNREACH_HOST_PROHIB: 704 case ICMP_UNREACH_FILTER_PROHIB: 705 code = PRC_UNREACH_ADMIN_PROHIB; 706 break; 707 708 default: 709 goto badcode; 710 } 711 goto deliver; 712 713 case ICMP_TIMXCEED: 714 if (code > 1) 715 goto badcode; 716 code += PRC_TIMXCEED_INTRANS; 717 goto deliver; 718 719 case ICMP_PARAMPROB: 720 if (code > 1) 721 goto badcode; 722 code = PRC_PARAMPROB; 723 goto deliver; 724 725 case ICMP_SOURCEQUENCH: 726 if (code) 727 goto badcode; 728 if (discard_sourcequench) 729 break; 730 code = PRC_QUENCH; 731 deliver: 732 /* 733 * Problem with datagram; advise higher level routines. 734 */ 735 if (icmplen < ICMP_ADVLENMIN || icmplen < ICMP_ADVLEN(icp) || 736 IP_VHL_HL(icp->icmp_ip.ip_vhl) < (sizeof(struct ip) >> 2)) { 737 icmpstat.icps_badlen++; 738 goto freeit; 739 } 740 /* Discard ICMP's in response to multicast packets */ 741 if (IN_MULTICAST(ntohl(icp->icmp_ip.ip_dst.s_addr))) 742 goto badcode; 743 #ifdef ICMPPRINTFS 744 if (icmpprintfs) 745 kprintf("deliver to protocol %d\n", icp->icmp_ip.ip_p); 746 #endif 747 icmpsrc.sin_addr = icp->icmp_ip.ip_dst; 748 749 /* 750 * MTU discovery 751 */ 752 if (code == PRC_MSGSIZE) { 753 /* Run MTU discovery in all netisrs */ 754 if (icmp_mtudisc_start(m, hlen, proto)) { 755 /* Forwarded; done */ 756 return IPPROTO_DONE; 757 } 758 /* Move on; run rip_input() directly */ 759 } else { 760 struct protosw *pr; 761 struct lwkt_port *port; 762 int cpu; 763 764 pr = &inetsw[ip_protox[icp->icmp_ip.ip_p]]; 765 port = so_pr_ctlport(pr, code, 766 (struct sockaddr *)&icmpsrc, &icp->icmp_ip, &cpu); 767 if (port != NULL) { 768 if (cpu == ncpus) { 769 if (ncpus > 1) { 770 /* 771 * Run pr_ctlinput in all 772 * netisrs 773 */ 774 icmp_ctlinput_global_start(m, 775 code, hlen, proto); 776 return IPPROTO_DONE; 777 } 778 /* 779 * There is only one netisr; run 780 * pr_ctlinput directly. 781 */ 782 } else if (cpu != mycpuid) { 783 /* 784 * Send to the target netisr to run 785 * pr_ctlinput. 786 */ 787 icmp_ctlinput_start(m, port, 788 code, hlen, proto); 789 return IPPROTO_DONE; 790 } 791 792 /* 793 * The target netisr is this netisr. 794 * 795 * XXX if the packet contains [IPv4 AH TCP], 796 * we can't make a notification to TCP layer. 797 */ 798 so_pr_ctlinput_direct(pr, code, 799 (struct sockaddr *)&icmpsrc, &icp->icmp_ip); 800 } 801 /* Move on; run rip_input() directly */ 802 } 803 break; 804 badcode: 805 icmpstat.icps_badcode++; 806 break; 807 808 case ICMP_ECHO: 809 if (!icmpbmcastecho 810 && (m->m_flags & (M_MCAST | M_BCAST)) != 0) { 811 icmpstat.icps_bmcastecho++; 812 break; 813 } 814 icp->icmp_type = ICMP_ECHOREPLY; 815 #ifdef ICMP_BANDLIM 816 if (badport_bandlim(BANDLIM_ICMP_ECHO) < 0) 817 goto freeit; 818 else 819 #endif 820 goto reflect; 821 822 case ICMP_TSTAMP: 823 if (!icmpbmcastecho 824 && (m->m_flags & (M_MCAST | M_BCAST)) != 0) { 825 icmpstat.icps_bmcasttstamp++; 826 break; 827 } 828 if (icmplen < ICMP_TSLEN) { 829 icmpstat.icps_badlen++; 830 break; 831 } 832 icp->icmp_type = ICMP_TSTAMPREPLY; 833 icp->icmp_rtime = iptime(); 834 icp->icmp_ttime = icp->icmp_rtime; /* bogus, do later! */ 835 #ifdef ICMP_BANDLIM 836 if (badport_bandlim(BANDLIM_ICMP_TSTAMP) < 0) 837 goto freeit; 838 else 839 #endif 840 goto reflect; 841 842 case ICMP_MASKREQ: 843 if (icmpmaskrepl == 0) 844 break; 845 /* 846 * We are not able to respond with all ones broadcast 847 * unless we receive it over a point-to-point interface. 848 */ 849 if (icmplen < ICMP_MASKLEN) 850 break; 851 switch (ip->ip_dst.s_addr) { 852 853 case INADDR_BROADCAST: 854 case INADDR_ANY: 855 icmpdst.sin_addr = ip->ip_src; 856 break; 857 858 default: 859 icmpdst.sin_addr = ip->ip_dst; 860 } 861 ia = (struct in_ifaddr *)ifaof_ifpforaddr( 862 (struct sockaddr *)&icmpdst, m->m_pkthdr.rcvif); 863 if (ia == NULL) 864 break; 865 if (ia->ia_ifp == 0) 866 break; 867 icp->icmp_type = ICMP_MASKREPLY; 868 icp->icmp_mask = ia->ia_sockmask.sin_addr.s_addr; 869 if (ip->ip_src.s_addr == 0) { 870 if (ia->ia_ifp->if_flags & IFF_BROADCAST) 871 ip->ip_src = satosin(&ia->ia_broadaddr)->sin_addr; 872 else if (ia->ia_ifp->if_flags & IFF_POINTOPOINT) 873 ip->ip_src = satosin(&ia->ia_dstaddr)->sin_addr; 874 } 875 reflect: 876 ip->ip_len += hlen; /* since ip_input deducts this */ 877 icmpstat.icps_reflect++; 878 icmpstat.icps_outhist[icp->icmp_type]++; 879 icmp_reflect(m); 880 return(IPPROTO_DONE); 881 882 case ICMP_REDIRECT: 883 if (log_redirect) { 884 char src_buf[INET_ADDRSTRLEN]; 885 char dst_buf[INET_ADDRSTRLEN]; 886 char gwy_buf[INET_ADDRSTRLEN]; 887 888 kprintf("icmp redirect from %s: %s => %s\n", 889 inet_ntop(AF_INET, &ip->ip_src, 890 src_buf, INET_ADDRSTRLEN), 891 inet_ntop(AF_INET, &icp->icmp_ip.ip_dst, 892 dst_buf, INET_ADDRSTRLEN), 893 inet_ntop(AF_INET, &icp->icmp_gwaddr, 894 gwy_buf, INET_ADDRSTRLEN)); 895 } 896 if (drop_redirect) 897 break; 898 if (code > 3) 899 goto badcode; 900 if (icmplen < ICMP_ADVLENMIN || icmplen < ICMP_ADVLEN(icp) || 901 IP_VHL_HL(icp->icmp_ip.ip_vhl) < (sizeof(struct ip) >> 2)) { 902 icmpstat.icps_badlen++; 903 break; 904 } 905 #ifdef ICMPPRINTFS 906 if (icmpprintfs) { 907 char dst_buf[INET_ADDRSTRLEN], gw_buf[INET_ADDRSTRLEN]; 908 909 kprintf("redirect dst %s to %s\n", 910 inet_ntop(AF_INET, &icp->icmp_ip.ip_dst, 911 dst_buf, INET_ADDRSTRLEN), 912 inet_ntop(AF_INET, &icp->icmp_gwaddr, 913 gw_buf, INET_ADDRSTRLEN)); 914 } 915 #endif 916 icmpsrc.sin_addr = icp->icmp_ip.ip_dst; 917 918 /* Run redirect in all netisrs */ 919 if (icmp_redirect_start(m, hlen, proto)) { 920 /* Forwarded; done */ 921 return IPPROTO_DONE; 922 } 923 /* Move on; run rip_input() directly */ 924 #ifdef IPSEC 925 key_sa_routechange((struct sockaddr *)&icmpsrc); 926 #endif 927 break; 928 929 /* 930 * No kernel processing for the following; 931 * just fall through to send to raw listener. 932 */ 933 case ICMP_ECHOREPLY: 934 case ICMP_ROUTERADVERT: 935 case ICMP_ROUTERSOLICIT: 936 case ICMP_TSTAMPREPLY: 937 case ICMP_IREQREPLY: 938 case ICMP_MASKREPLY: 939 default: 940 break; 941 } 942 943 raw: 944 *mp = m; 945 rip_input(mp, offp, proto); 946 return(IPPROTO_DONE); 947 948 freeit: 949 m_freem(m); 950 return(IPPROTO_DONE); 951 } 952 953 /* 954 * Reflect the ip packet back to the source 955 */ 956 static void 957 icmp_reflect(struct mbuf *m) 958 { 959 struct ip *ip = mtod(m, struct ip *); 960 struct in_ifaddr *ia; 961 struct in_ifaddr_container *iac; 962 struct ifaddr_container *ifac; 963 struct ifnet *ifp; 964 struct in_addr t; 965 struct mbuf *opts = NULL; 966 int optlen = (IP_VHL_HL(ip->ip_vhl) << 2) - sizeof(struct ip); 967 struct route *ro = NULL, rt; 968 969 if (!in_canforward(ip->ip_src) && 970 ((ntohl(ip->ip_src.s_addr) & IN_CLASSA_NET) != 971 (IN_LOOPBACKNET << IN_CLASSA_NSHIFT))) { 972 m_freem(m); /* Bad return address */ 973 icmpstat.icps_badaddr++; 974 goto done; /* Ip_output() will check for broadcast */ 975 } 976 t = ip->ip_dst; 977 ip->ip_dst = ip->ip_src; 978 979 ro = &rt; 980 bzero(ro, sizeof *ro); 981 982 /* 983 * If the incoming packet was addressed directly to us, 984 * use dst as the src for the reply. Otherwise (broadcast 985 * or anonymous), use the address which corresponds 986 * to the incoming interface. 987 */ 988 ia = NULL; 989 LIST_FOREACH(iac, INADDR_HASH(t.s_addr), ia_hash) { 990 if (t.s_addr == IA_SIN(iac->ia)->sin_addr.s_addr) { 991 ia = iac->ia; 992 goto match; 993 } 994 } 995 ifp = m->m_pkthdr.rcvif; 996 if (ifp != NULL && (ifp->if_flags & IFF_BROADCAST)) { 997 TAILQ_FOREACH(ifac, &ifp->if_addrheads[mycpuid], ifa_link) { 998 struct ifaddr *ifa = ifac->ifa; 999 1000 if (ifa->ifa_addr->sa_family != AF_INET) 1001 continue; 1002 ia = ifatoia(ifa); 1003 if (satosin(&ia->ia_broadaddr)->sin_addr.s_addr == 1004 t.s_addr) 1005 goto match; 1006 } 1007 } 1008 /* 1009 * If the packet was transiting through us, use the address of 1010 * the interface the packet came through in. If that interface 1011 * doesn't have a suitable IP address, the normal selection 1012 * criteria apply. 1013 */ 1014 if (icmp_rfi && ifp != NULL) { 1015 TAILQ_FOREACH(ifac, &ifp->if_addrheads[mycpuid], ifa_link) { 1016 struct ifaddr *ifa = ifac->ifa; 1017 1018 if (ifa->ifa_addr->sa_family != AF_INET) 1019 continue; 1020 ia = ifatoia(ifa); 1021 goto match; 1022 } 1023 } 1024 /* 1025 * If the incoming packet was not addressed directly to us, use 1026 * designated interface for icmp replies specified by sysctl 1027 * net.inet.icmp.reply_src (default not set). Otherwise continue 1028 * with normal source selection. 1029 */ 1030 if (icmp_reply_src[0] != '\0' && 1031 (ifp = ifunit_netisr(icmp_reply_src))) { 1032 TAILQ_FOREACH(ifac, &ifp->if_addrheads[mycpuid], ifa_link) { 1033 struct ifaddr *ifa = ifac->ifa; 1034 1035 if (ifa->ifa_addr->sa_family != AF_INET) 1036 continue; 1037 ia = ifatoia(ifa); 1038 goto match; 1039 } 1040 } 1041 /* 1042 * If the packet was transiting through us, use the address of 1043 * the interface that is the closest to the packet source. 1044 * When we don't have a route back to the packet source, stop here 1045 * and drop the packet. 1046 */ 1047 ia = ip_rtaddr(ip->ip_dst, ro); 1048 if (ia == NULL) { 1049 m_freem(m); 1050 icmpstat.icps_noroute++; 1051 goto done; 1052 } 1053 match: 1054 t = IA_SIN(ia)->sin_addr; 1055 ip->ip_src = t; 1056 ip->ip_ttl = ip_defttl; 1057 1058 if (optlen > 0) { 1059 u_char *cp; 1060 int opt, cnt; 1061 u_int len; 1062 1063 /* 1064 * Retrieve any source routing from the incoming packet; 1065 * add on any record-route or timestamp options. 1066 */ 1067 cp = (u_char *) (ip + 1); 1068 if ((opts = ip_srcroute(m)) == NULL && 1069 (opts = m_gethdr(M_NOWAIT, MT_HEADER))) { 1070 opts->m_len = sizeof(struct in_addr); 1071 mtod(opts, struct in_addr *)->s_addr = 0; 1072 } 1073 if (opts) { 1074 #ifdef ICMPPRINTFS 1075 if (icmpprintfs) 1076 kprintf("icmp_reflect optlen %d rt %d => ", 1077 optlen, opts->m_len); 1078 #endif 1079 for (cnt = optlen; cnt > 0; cnt -= len, cp += len) { 1080 opt = cp[IPOPT_OPTVAL]; 1081 if (opt == IPOPT_EOL) 1082 break; 1083 if (opt == IPOPT_NOP) 1084 len = 1; 1085 else { 1086 if (cnt < IPOPT_OLEN + sizeof *cp) 1087 break; 1088 len = cp[IPOPT_OLEN]; 1089 if (len < IPOPT_OLEN + sizeof *cp || 1090 len > cnt) 1091 break; 1092 } 1093 /* 1094 * Should check for overflow, but it 1095 * "can't happen". 1096 */ 1097 if (opt == IPOPT_RR || opt == IPOPT_TS || 1098 opt == IPOPT_SECURITY) { 1099 bcopy(cp, 1100 mtod(opts, caddr_t) + opts->m_len, 1101 len); 1102 opts->m_len += len; 1103 } 1104 } 1105 /* Terminate & pad, if necessary */ 1106 cnt = opts->m_len % 4; 1107 if (cnt) { 1108 for (; cnt < 4; cnt++) { 1109 *(mtod(opts, caddr_t) + opts->m_len) = 1110 IPOPT_EOL; 1111 opts->m_len++; 1112 } 1113 } 1114 #ifdef ICMPPRINTFS 1115 if (icmpprintfs) 1116 kprintf("%d\n", opts->m_len); 1117 #endif 1118 } 1119 /* 1120 * Now strip out original options by copying rest of first 1121 * mbuf's data back, and adjust the IP length. 1122 */ 1123 ip->ip_len -= optlen; 1124 ip->ip_vhl = IP_VHL_BORING; 1125 m->m_len -= optlen; 1126 if (m->m_flags & M_PKTHDR) 1127 m->m_pkthdr.len -= optlen; 1128 optlen += sizeof(struct ip); 1129 bcopy((caddr_t)ip + optlen, ip + 1, 1130 m->m_len - sizeof(struct ip)); 1131 } 1132 m->m_pkthdr.fw_flags &= FW_MBUF_GENERATED; 1133 m->m_flags &= ~(M_BCAST|M_MCAST); 1134 icmp_send(m, opts, ro); 1135 done: 1136 if (opts) 1137 m_free(opts); 1138 if (ro && ro->ro_rt) 1139 RTFREE(ro->ro_rt); 1140 } 1141 1142 /* 1143 * Send an icmp packet back to the ip level, 1144 * after supplying a checksum. 1145 */ 1146 static void 1147 icmp_send(struct mbuf *m, struct mbuf *opts, struct route *rt) 1148 { 1149 struct ip *ip = mtod(m, struct ip *); 1150 struct icmp *icp; 1151 int hlen; 1152 1153 hlen = IP_VHL_HL(ip->ip_vhl) << 2; 1154 m->m_data += hlen; 1155 m->m_len -= hlen; 1156 icp = mtod(m, struct icmp *); 1157 icp->icmp_cksum = 0; 1158 icp->icmp_cksum = in_cksum(m, ip->ip_len - hlen); 1159 m->m_data -= hlen; 1160 m->m_len += hlen; 1161 m->m_pkthdr.rcvif = NULL; 1162 #ifdef ICMPPRINTFS 1163 if (icmpprintfs) { 1164 char dst_buf[INET_ADDRSTRLEN], src_buf[INET_ADDRSTRLEN]; 1165 1166 kprintf("icmp_send dst %s src %s\n", 1167 inet_ntop(AF_INET, &ip->ip_dst, dst_buf, INET_ADDRSTRLEN), 1168 inet_ntop(AF_INET, &ip->ip_src, src_buf, INET_ADDRSTRLEN)); 1169 } 1170 #endif 1171 ip_output(m, opts, rt, 0, NULL, NULL); 1172 } 1173 1174 n_time 1175 iptime(void) 1176 { 1177 struct timeval atv; 1178 u_long t; 1179 1180 getmicrotime(&atv); 1181 t = (atv.tv_sec % (24*60*60)) * 1000 + atv.tv_usec / 1000; 1182 return (htonl(t)); 1183 } 1184 1185 #if 1 1186 /* 1187 * Return the next larger or smaller MTU plateau (table from RFC 1191) 1188 * given current value MTU. If DIR is less than zero, a larger plateau 1189 * is returned; otherwise, a smaller value is returned. 1190 */ 1191 int 1192 ip_next_mtu(int mtu, int dir) 1193 { 1194 static int mtutab[] = { 1195 65535, 32000, 17914, 8166, 4352, 2002, 1492, 1006, 508, 296, 1196 68, 0 1197 }; 1198 int i; 1199 1200 for (i = 0; i < (sizeof mtutab) / (sizeof mtutab[0]); i++) { 1201 if (mtu >= mtutab[i]) 1202 break; 1203 } 1204 1205 if (dir < 0) { 1206 if (i == 0) { 1207 return 0; 1208 } else { 1209 return mtutab[i - 1]; 1210 } 1211 } else { 1212 if (mtutab[i] == 0) { 1213 return 0; 1214 } else if(mtu > mtutab[i]) { 1215 return mtutab[i]; 1216 } else { 1217 return mtutab[i + 1]; 1218 } 1219 } 1220 } 1221 #endif 1222 1223 #ifdef ICMP_BANDLIM 1224 /* 1225 * badport_bandlim() - check for ICMP bandwidth limit 1226 * 1227 * Return 0 if it is ok to send an ICMP error response, -1 if we have 1228 * hit our bandwidth limit and it is not ok. 1229 * 1230 * If icmplim is <= 0, the feature is disabled and 0 is returned. 1231 * 1232 * For now we separate the TCP and UDP subsystems w/ different 'which' 1233 * values. We may eventually remove this separation (and simplify the 1234 * code further). 1235 * 1236 * Note that the printing of the error message is delayed so we can 1237 * properly print the icmp error rate that the system was trying to do 1238 * (i.e. 22000/100 pps, etc...). This can cause long delays in printing 1239 * the 'final' error, but it doesn't make sense to solve the printing 1240 * delay with more complex code. 1241 */ 1242 int 1243 badport_bandlim(int which) 1244 { 1245 static int lticks[BANDLIM_MAX + 1]; 1246 static int lpackets[BANDLIM_MAX + 1]; 1247 int dticks; 1248 const char *bandlimittype[] = { 1249 "Limiting icmp unreach response", 1250 "Limiting icmp ping response", 1251 "Limiting icmp tstamp response", 1252 "Limiting closed port RST response", 1253 "Limiting open port RST response" 1254 }; 1255 1256 /* 1257 * Return ok status if feature disabled or argument out of 1258 * ranage. 1259 */ 1260 1261 if (icmplim <= 0 || which > BANDLIM_MAX || which < 0) 1262 return(0); 1263 dticks = ticks - lticks[which]; 1264 1265 /* 1266 * reset stats when cumulative dt exceeds one second. 1267 */ 1268 1269 if ((unsigned int)dticks > hz) { 1270 if (lpackets[which] > icmplim && icmplim_output) { 1271 kprintf("%s from %d to %d packets per second\n", 1272 bandlimittype[which], 1273 lpackets[which], 1274 icmplim 1275 ); 1276 } 1277 lticks[which] = ticks; 1278 lpackets[which] = 0; 1279 } 1280 1281 /* 1282 * bump packet count 1283 */ 1284 1285 if (++lpackets[which] > icmplim) { 1286 return(-1); 1287 } 1288 return(0); 1289 } 1290 #endif 1291