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sys/netinet6/ip6_input.c
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1 /*- 2 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 3 * 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 project 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 PROJECT 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 PROJECT 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 * $KAME: ip6_input.c,v 1.259 2002/01/21 04:58:09 jinmei Exp $ 30 */ 31 32 /*- 33 * Copyright (c) 1982, 1986, 1988, 1993 34 * The Regents of the University of California. All rights reserved. 35 * 36 * Redistribution and use in source and binary forms, with or without 37 * modification, are permitted provided that the following conditions 38 * are met: 39 * 1. Redistributions of source code must retain the above copyright 40 * notice, this list of conditions and the following disclaimer. 41 * 2. Redistributions in binary form must reproduce the above copyright 42 * notice, this list of conditions and the following disclaimer in the 43 * documentation and/or other materials provided with the distribution. 44 * 4. Neither the name of the University nor the names of its contributors 45 * may be used to endorse or promote products derived from this software 46 * without specific prior written permission. 47 * 48 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 49 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 50 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 51 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 52 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 53 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 54 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 55 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 56 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 57 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 58 * SUCH DAMAGE. 59 * 60 * @(#)ip_input.c 8.2 (Berkeley) 1/4/94 61 */ 62 63 #include <sys/cdefs.h> 64 __FBSDID("$FreeBSD: releng/11.2/sys/netinet6/ip6_input.c 332513 2018-04-15 15:22:28Z kp $"); 65 66 #include "opt_inet.h" 67 #include "opt_inet6.h" 68 #include "opt_ipsec.h" 69 #include "opt_route.h" 70 #include "opt_rss.h" 71 72 #include <sys/param.h> 73 #include <sys/systm.h> 74 #include <sys/hhook.h> 75 #include <sys/malloc.h> 76 #include <sys/mbuf.h> 77 #include <sys/proc.h> 78 #include <sys/domain.h> 79 #include <sys/protosw.h> 80 #include <sys/sdt.h> 81 #include <sys/socket.h> 82 #include <sys/socketvar.h> 83 #include <sys/errno.h> 84 #include <sys/time.h> 85 #include <sys/kernel.h> 86 #include <sys/lock.h> 87 #include <sys/rmlock.h> 88 #include <sys/syslog.h> 89 #include <sys/sysctl.h> 90 91 #include <net/if.h> 92 #include <net/if_var.h> 93 #include <net/if_types.h> 94 #include <net/if_dl.h> 95 #include <net/route.h> 96 #include <net/netisr.h> 97 #include <net/rss_config.h> 98 #include <net/pfil.h> 99 #include <net/vnet.h> 100 101 #include <netinet/in.h> 102 #include <netinet/in_kdtrace.h> 103 #include <netinet/ip_var.h> 104 #include <netinet/in_systm.h> 105 #include <net/if_llatbl.h> 106 #ifdef INET 107 #include <netinet/ip.h> 108 #include <netinet/ip_icmp.h> 109 #endif /* INET */ 110 #include <netinet/ip6.h> 111 #include <netinet6/in6_var.h> 112 #include <netinet6/ip6_var.h> 113 #include <netinet/in_pcb.h> 114 #include <netinet/icmp6.h> 115 #include <netinet6/scope6_var.h> 116 #include <netinet6/in6_ifattach.h> 117 #include <netinet6/mld6_var.h> 118 #include <netinet6/nd6.h> 119 #include <netinet6/in6_rss.h> 120 121 #include <netipsec/ipsec_support.h> 122 123 #include <netinet6/ip6protosw.h> 124 125 extern struct domain inet6domain; 126 127 u_char ip6_protox[IPPROTO_MAX]; 128 VNET_DEFINE(struct in6_ifaddrhead, in6_ifaddrhead); 129 VNET_DEFINE(struct in6_ifaddrlisthead *, in6_ifaddrhashtbl); 130 VNET_DEFINE(u_long, in6_ifaddrhmask); 131 132 static struct netisr_handler ip6_nh = { 133 .nh_name = "ip6", 134 .nh_handler = ip6_input, 135 .nh_proto = NETISR_IPV6, 136 #ifdef RSS 137 .nh_m2cpuid = rss_soft_m2cpuid_v6, 138 .nh_policy = NETISR_POLICY_CPU, 139 .nh_dispatch = NETISR_DISPATCH_HYBRID, 140 #else 141 .nh_policy = NETISR_POLICY_FLOW, 142 #endif 143 }; 144 145 static int 146 sysctl_netinet6_intr_queue_maxlen(SYSCTL_HANDLER_ARGS) 147 { 148 int error, qlimit; 149 150 netisr_getqlimit(&ip6_nh, &qlimit); 151 error = sysctl_handle_int(oidp, &qlimit, 0, req); 152 if (error || !req->newptr) 153 return (error); 154 if (qlimit < 1) 155 return (EINVAL); 156 return (netisr_setqlimit(&ip6_nh, qlimit)); 157 } 158 SYSCTL_DECL(_net_inet6_ip6); 159 SYSCTL_PROC(_net_inet6_ip6, IPV6CTL_INTRQMAXLEN, intr_queue_maxlen, 160 CTLTYPE_INT|CTLFLAG_RW, 0, 0, sysctl_netinet6_intr_queue_maxlen, "I", 161 "Maximum size of the IPv6 input queue"); 162 163 #ifdef RSS 164 static struct netisr_handler ip6_direct_nh = { 165 .nh_name = "ip6_direct", 166 .nh_handler = ip6_direct_input, 167 .nh_proto = NETISR_IPV6_DIRECT, 168 .nh_m2cpuid = rss_soft_m2cpuid_v6, 169 .nh_policy = NETISR_POLICY_CPU, 170 .nh_dispatch = NETISR_DISPATCH_HYBRID, 171 }; 172 173 static int 174 sysctl_netinet6_intr_direct_queue_maxlen(SYSCTL_HANDLER_ARGS) 175 { 176 int error, qlimit; 177 178 netisr_getqlimit(&ip6_direct_nh, &qlimit); 179 error = sysctl_handle_int(oidp, &qlimit, 0, req); 180 if (error || !req->newptr) 181 return (error); 182 if (qlimit < 1) 183 return (EINVAL); 184 return (netisr_setqlimit(&ip6_direct_nh, qlimit)); 185 } 186 SYSCTL_PROC(_net_inet6_ip6, IPV6CTL_INTRDQMAXLEN, intr_direct_queue_maxlen, 187 CTLTYPE_INT|CTLFLAG_RW, 0, 0, sysctl_netinet6_intr_direct_queue_maxlen, 188 "I", "Maximum size of the IPv6 direct input queue"); 189 190 #endif 191 192 VNET_DEFINE(struct pfil_head, inet6_pfil_hook); 193 194 VNET_PCPUSTAT_DEFINE(struct ip6stat, ip6stat); 195 VNET_PCPUSTAT_SYSINIT(ip6stat); 196 #ifdef VIMAGE 197 VNET_PCPUSTAT_SYSUNINIT(ip6stat); 198 #endif /* VIMAGE */ 199 200 struct rmlock in6_ifaddr_lock; 201 RM_SYSINIT(in6_ifaddr_lock, &in6_ifaddr_lock, "in6_ifaddr_lock"); 202 203 static int ip6_hopopts_input(u_int32_t *, u_int32_t *, struct mbuf **, int *); 204 #ifdef PULLDOWN_TEST 205 static struct mbuf *ip6_pullexthdr(struct mbuf *, size_t, int); 206 #endif 207 208 /* 209 * IP6 initialization: fill in IP6 protocol switch table. 210 * All protocols not implemented in kernel go to raw IP6 protocol handler. 211 */ 212 void 213 ip6_init(void) 214 { 215 struct protosw *pr; 216 int i; 217 218 TUNABLE_INT_FETCH("net.inet6.ip6.auto_linklocal", 219 &V_ip6_auto_linklocal); 220 TUNABLE_INT_FETCH("net.inet6.ip6.accept_rtadv", &V_ip6_accept_rtadv); 221 TUNABLE_INT_FETCH("net.inet6.ip6.no_radr", &V_ip6_no_radr); 222 223 TAILQ_INIT(&V_in6_ifaddrhead); 224 V_in6_ifaddrhashtbl = hashinit(IN6ADDR_NHASH, M_IFADDR, 225 &V_in6_ifaddrhmask); 226 227 /* Initialize packet filter hooks. */ 228 V_inet6_pfil_hook.ph_type = PFIL_TYPE_AF; 229 V_inet6_pfil_hook.ph_af = AF_INET6; 230 if ((i = pfil_head_register(&V_inet6_pfil_hook)) != 0) 231 printf("%s: WARNING: unable to register pfil hook, " 232 "error %d\n", __func__, i); 233 234 if (hhook_head_register(HHOOK_TYPE_IPSEC_IN, AF_INET6, 235 &V_ipsec_hhh_in[HHOOK_IPSEC_INET6], 236 HHOOK_WAITOK | HHOOK_HEADISINVNET) != 0) 237 printf("%s: WARNING: unable to register input helper hook\n", 238 __func__); 239 if (hhook_head_register(HHOOK_TYPE_IPSEC_OUT, AF_INET6, 240 &V_ipsec_hhh_out[HHOOK_IPSEC_INET6], 241 HHOOK_WAITOK | HHOOK_HEADISINVNET) != 0) 242 printf("%s: WARNING: unable to register output helper hook\n", 243 __func__); 244 245 scope6_init(); 246 addrsel_policy_init(); 247 nd6_init(); 248 frag6_init(); 249 250 V_ip6_desync_factor = arc4random() % MAX_TEMP_DESYNC_FACTOR; 251 252 /* Skip global initialization stuff for non-default instances. */ 253 #ifdef VIMAGE 254 if (!IS_DEFAULT_VNET(curvnet)) { 255 netisr_register_vnet(&ip6_nh); 256 #ifdef RSS 257 netisr_register_vnet(&ip6_direct_nh); 258 #endif 259 return; 260 } 261 #endif 262 263 pr = pffindproto(PF_INET6, IPPROTO_RAW, SOCK_RAW); 264 if (pr == NULL) 265 panic("ip6_init"); 266 267 /* Initialize the entire ip6_protox[] array to IPPROTO_RAW. */ 268 for (i = 0; i < IPPROTO_MAX; i++) 269 ip6_protox[i] = pr - inet6sw; 270 /* 271 * Cycle through IP protocols and put them into the appropriate place 272 * in ip6_protox[]. 273 */ 274 for (pr = inet6domain.dom_protosw; 275 pr < inet6domain.dom_protoswNPROTOSW; pr++) 276 if (pr->pr_domain->dom_family == PF_INET6 && 277 pr->pr_protocol && pr->pr_protocol != IPPROTO_RAW) { 278 /* Be careful to only index valid IP protocols. */ 279 if (pr->pr_protocol < IPPROTO_MAX) 280 ip6_protox[pr->pr_protocol] = pr - inet6sw; 281 } 282 283 netisr_register(&ip6_nh); 284 #ifdef RSS 285 netisr_register(&ip6_direct_nh); 286 #endif 287 } 288 289 /* 290 * The protocol to be inserted into ip6_protox[] must be already registered 291 * in inet6sw[], either statically or through pf_proto_register(). 292 */ 293 int 294 ip6proto_register(short ip6proto) 295 { 296 struct protosw *pr; 297 298 /* Sanity checks. */ 299 if (ip6proto <= 0 || ip6proto >= IPPROTO_MAX) 300 return (EPROTONOSUPPORT); 301 302 /* 303 * The protocol slot must not be occupied by another protocol 304 * already. An index pointing to IPPROTO_RAW is unused. 305 */ 306 pr = pffindproto(PF_INET6, IPPROTO_RAW, SOCK_RAW); 307 if (pr == NULL) 308 return (EPFNOSUPPORT); 309 if (ip6_protox[ip6proto] != pr - inet6sw) /* IPPROTO_RAW */ 310 return (EEXIST); 311 312 /* 313 * Find the protocol position in inet6sw[] and set the index. 314 */ 315 for (pr = inet6domain.dom_protosw; 316 pr < inet6domain.dom_protoswNPROTOSW; pr++) { 317 if (pr->pr_domain->dom_family == PF_INET6 && 318 pr->pr_protocol && pr->pr_protocol == ip6proto) { 319 ip6_protox[pr->pr_protocol] = pr - inet6sw; 320 return (0); 321 } 322 } 323 return (EPROTONOSUPPORT); 324 } 325 326 int 327 ip6proto_unregister(short ip6proto) 328 { 329 struct protosw *pr; 330 331 /* Sanity checks. */ 332 if (ip6proto <= 0 || ip6proto >= IPPROTO_MAX) 333 return (EPROTONOSUPPORT); 334 335 /* Check if the protocol was indeed registered. */ 336 pr = pffindproto(PF_INET6, IPPROTO_RAW, SOCK_RAW); 337 if (pr == NULL) 338 return (EPFNOSUPPORT); 339 if (ip6_protox[ip6proto] == pr - inet6sw) /* IPPROTO_RAW */ 340 return (ENOENT); 341 342 /* Reset the protocol slot to IPPROTO_RAW. */ 343 ip6_protox[ip6proto] = pr - inet6sw; 344 return (0); 345 } 346 347 #ifdef VIMAGE 348 static void 349 ip6_destroy(void *unused __unused) 350 { 351 struct ifaddr *ifa, *nifa; 352 struct ifnet *ifp; 353 int error; 354 355 #ifdef RSS 356 netisr_unregister_vnet(&ip6_direct_nh); 357 #endif 358 netisr_unregister_vnet(&ip6_nh); 359 360 if ((error = pfil_head_unregister(&V_inet6_pfil_hook)) != 0) 361 printf("%s: WARNING: unable to unregister pfil hook, " 362 "error %d\n", __func__, error); 363 error = hhook_head_deregister(V_ipsec_hhh_in[HHOOK_IPSEC_INET6]); 364 if (error != 0) { 365 printf("%s: WARNING: unable to deregister input helper hook " 366 "type HHOOK_TYPE_IPSEC_IN, id HHOOK_IPSEC_INET6: " 367 "error %d returned\n", __func__, error); 368 } 369 error = hhook_head_deregister(V_ipsec_hhh_out[HHOOK_IPSEC_INET6]); 370 if (error != 0) { 371 printf("%s: WARNING: unable to deregister output helper hook " 372 "type HHOOK_TYPE_IPSEC_OUT, id HHOOK_IPSEC_INET6: " 373 "error %d returned\n", __func__, error); 374 } 375 376 /* Cleanup addresses. */ 377 IFNET_RLOCK(); 378 TAILQ_FOREACH(ifp, &V_ifnet, if_link) { 379 /* Cannot lock here - lock recursion. */ 380 /* IF_ADDR_LOCK(ifp); */ 381 TAILQ_FOREACH_SAFE(ifa, &ifp->if_addrhead, ifa_link, nifa) { 382 383 if (ifa->ifa_addr->sa_family != AF_INET6) 384 continue; 385 in6_purgeaddr(ifa); 386 } 387 /* IF_ADDR_UNLOCK(ifp); */ 388 in6_ifdetach_destroy(ifp); 389 mld_domifdetach(ifp); 390 /* Make sure any routes are gone as well. */ 391 rt_flushifroutes_af(ifp, AF_INET6); 392 } 393 IFNET_RUNLOCK(); 394 395 nd6_destroy(); 396 in6_ifattach_destroy(); 397 398 hashdestroy(V_in6_ifaddrhashtbl, M_IFADDR, V_in6_ifaddrhmask); 399 } 400 401 VNET_SYSUNINIT(inet6, SI_SUB_PROTO_DOMAIN, SI_ORDER_THIRD, ip6_destroy, NULL); 402 #endif 403 404 static int 405 ip6_input_hbh(struct mbuf *m, uint32_t *plen, uint32_t *rtalert, int *off, 406 int *nxt, int *ours) 407 { 408 struct ip6_hdr *ip6; 409 struct ip6_hbh *hbh; 410 411 if (ip6_hopopts_input(plen, rtalert, &m, off)) { 412 #if 0 /*touches NULL pointer*/ 413 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard); 414 #endif 415 goto out; /* m have already been freed */ 416 } 417 418 /* adjust pointer */ 419 ip6 = mtod(m, struct ip6_hdr *); 420 421 /* 422 * if the payload length field is 0 and the next header field 423 * indicates Hop-by-Hop Options header, then a Jumbo Payload 424 * option MUST be included. 425 */ 426 if (ip6->ip6_plen == 0 && *plen == 0) { 427 /* 428 * Note that if a valid jumbo payload option is 429 * contained, ip6_hopopts_input() must set a valid 430 * (non-zero) payload length to the variable plen. 431 */ 432 IP6STAT_INC(ip6s_badoptions); 433 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard); 434 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_hdrerr); 435 icmp6_error(m, ICMP6_PARAM_PROB, 436 ICMP6_PARAMPROB_HEADER, 437 (caddr_t)&ip6->ip6_plen - (caddr_t)ip6); 438 goto out; 439 } 440 #ifndef PULLDOWN_TEST 441 /* ip6_hopopts_input() ensures that mbuf is contiguous */ 442 hbh = (struct ip6_hbh *)(ip6 + 1); 443 #else 444 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, sizeof(struct ip6_hdr), 445 sizeof(struct ip6_hbh)); 446 if (hbh == NULL) { 447 IP6STAT_INC(ip6s_tooshort); 448 goto out; 449 } 450 #endif 451 *nxt = hbh->ip6h_nxt; 452 453 /* 454 * If we are acting as a router and the packet contains a 455 * router alert option, see if we know the option value. 456 * Currently, we only support the option value for MLD, in which 457 * case we should pass the packet to the multicast routing 458 * daemon. 459 */ 460 if (*rtalert != ~0) { 461 switch (*rtalert) { 462 case IP6OPT_RTALERT_MLD: 463 if (V_ip6_forwarding) 464 *ours = 1; 465 break; 466 default: 467 /* 468 * RFC2711 requires unrecognized values must be 469 * silently ignored. 470 */ 471 break; 472 } 473 } 474 475 return (0); 476 477 out: 478 return (1); 479 } 480 481 #ifdef RSS 482 /* 483 * IPv6 direct input routine. 484 * 485 * This is called when reinjecting completed fragments where 486 * all of the previous checking and book-keeping has been done. 487 */ 488 void 489 ip6_direct_input(struct mbuf *m) 490 { 491 int off, nxt; 492 int nest; 493 struct m_tag *mtag; 494 struct ip6_direct_ctx *ip6dc; 495 496 mtag = m_tag_locate(m, MTAG_ABI_IPV6, IPV6_TAG_DIRECT, NULL); 497 KASSERT(mtag != NULL, ("Reinjected packet w/o direct ctx tag!")); 498 499 ip6dc = (struct ip6_direct_ctx *)(mtag + 1); 500 nxt = ip6dc->ip6dc_nxt; 501 off = ip6dc->ip6dc_off; 502 503 nest = 0; 504 505 m_tag_delete(m, mtag); 506 507 while (nxt != IPPROTO_DONE) { 508 if (V_ip6_hdrnestlimit && (++nest > V_ip6_hdrnestlimit)) { 509 IP6STAT_INC(ip6s_toomanyhdr); 510 goto bad; 511 } 512 513 /* 514 * protection against faulty packet - there should be 515 * more sanity checks in header chain processing. 516 */ 517 if (m->m_pkthdr.len < off) { 518 IP6STAT_INC(ip6s_tooshort); 519 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_truncated); 520 goto bad; 521 } 522 523 #if defined(IPSEC) || defined(IPSEC_SUPPORT) 524 if (IPSEC_ENABLED(ipv6)) { 525 if (IPSEC_INPUT(ipv6, m, off, nxt) != 0) 526 return; 527 } 528 #endif /* IPSEC */ 529 530 nxt = (*inet6sw[ip6_protox[nxt]].pr_input)(&m, &off, nxt); 531 } 532 return; 533 bad: 534 m_freem(m); 535 } 536 #endif 537 538 void 539 ip6_input(struct mbuf *m) 540 { 541 struct in6_addr odst; 542 struct ip6_hdr *ip6; 543 struct in6_ifaddr *ia; 544 struct ifnet *rcvif; 545 u_int32_t plen; 546 u_int32_t rtalert = ~0; 547 int off = sizeof(struct ip6_hdr), nest; 548 int nxt, ours = 0; 549 int srcrt = 0; 550 551 /* 552 * Drop the packet if IPv6 operation is disabled on the interface. 553 */ 554 rcvif = m->m_pkthdr.rcvif; 555 if ((ND_IFINFO(rcvif)->flags & ND6_IFF_IFDISABLED)) 556 goto bad; 557 558 #if defined(IPSEC) || defined(IPSEC_SUPPORT) 559 /* 560 * should the inner packet be considered authentic? 561 * see comment in ah4_input(). 562 * NB: m cannot be NULL when passed to the input routine 563 */ 564 565 m->m_flags &= ~M_AUTHIPHDR; 566 m->m_flags &= ~M_AUTHIPDGM; 567 568 #endif /* IPSEC */ 569 570 if (m->m_flags & M_FASTFWD_OURS) { 571 /* 572 * Firewall changed destination to local. 573 */ 574 ip6 = mtod(m, struct ip6_hdr *); 575 goto passin; 576 } 577 578 /* 579 * mbuf statistics 580 */ 581 if (m->m_flags & M_EXT) { 582 if (m->m_next) 583 IP6STAT_INC(ip6s_mext2m); 584 else 585 IP6STAT_INC(ip6s_mext1); 586 } else { 587 if (m->m_next) { 588 if (m->m_flags & M_LOOP) { 589 IP6STAT_INC(ip6s_m2m[V_loif->if_index]); 590 } else if (rcvif->if_index < IP6S_M2MMAX) 591 IP6STAT_INC(ip6s_m2m[rcvif->if_index]); 592 else 593 IP6STAT_INC(ip6s_m2m[0]); 594 } else 595 IP6STAT_INC(ip6s_m1); 596 } 597 598 in6_ifstat_inc(rcvif, ifs6_in_receive); 599 IP6STAT_INC(ip6s_total); 600 601 #ifndef PULLDOWN_TEST 602 /* 603 * L2 bridge code and some other code can return mbuf chain 604 * that does not conform to KAME requirement. too bad. 605 * XXX: fails to join if interface MTU > MCLBYTES. jumbogram? 606 */ 607 if (m && m->m_next != NULL && m->m_pkthdr.len < MCLBYTES) { 608 struct mbuf *n; 609 610 if (m->m_pkthdr.len > MHLEN) 611 n = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR); 612 else 613 n = m_gethdr(M_NOWAIT, MT_DATA); 614 if (n == NULL) 615 goto bad; 616 617 m_move_pkthdr(n, m); 618 m_copydata(m, 0, n->m_pkthdr.len, mtod(n, caddr_t)); 619 n->m_len = n->m_pkthdr.len; 620 m_freem(m); 621 m = n; 622 } 623 IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), /* nothing */); 624 #endif 625 626 if (m->m_len < sizeof(struct ip6_hdr)) { 627 if ((m = m_pullup(m, sizeof(struct ip6_hdr))) == NULL) { 628 IP6STAT_INC(ip6s_toosmall); 629 in6_ifstat_inc(rcvif, ifs6_in_hdrerr); 630 goto bad; 631 } 632 } 633 634 ip6 = mtod(m, struct ip6_hdr *); 635 if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) { 636 IP6STAT_INC(ip6s_badvers); 637 in6_ifstat_inc(rcvif, ifs6_in_hdrerr); 638 goto bad; 639 } 640 641 IP6STAT_INC(ip6s_nxthist[ip6->ip6_nxt]); 642 IP_PROBE(receive, NULL, NULL, ip6, rcvif, NULL, ip6); 643 644 /* 645 * Check against address spoofing/corruption. 646 */ 647 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_src) || 648 IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_dst)) { 649 /* 650 * XXX: "badscope" is not very suitable for a multicast source. 651 */ 652 IP6STAT_INC(ip6s_badscope); 653 in6_ifstat_inc(rcvif, ifs6_in_addrerr); 654 goto bad; 655 } 656 if (IN6_IS_ADDR_MC_INTFACELOCAL(&ip6->ip6_dst) && 657 !(m->m_flags & M_LOOP)) { 658 /* 659 * In this case, the packet should come from the loopback 660 * interface. However, we cannot just check the if_flags, 661 * because ip6_mloopback() passes the "actual" interface 662 * as the outgoing/incoming interface. 663 */ 664 IP6STAT_INC(ip6s_badscope); 665 in6_ifstat_inc(rcvif, ifs6_in_addrerr); 666 goto bad; 667 } 668 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) && 669 IPV6_ADDR_MC_SCOPE(&ip6->ip6_dst) == 0) { 670 /* 671 * RFC4291 2.7: 672 * Nodes must not originate a packet to a multicast address 673 * whose scop field contains the reserved value 0; if such 674 * a packet is received, it must be silently dropped. 675 */ 676 IP6STAT_INC(ip6s_badscope); 677 in6_ifstat_inc(rcvif, ifs6_in_addrerr); 678 goto bad; 679 } 680 #ifdef ALTQ 681 if (altq_input != NULL && (*altq_input)(m, AF_INET6) == 0) { 682 /* packet is dropped by traffic conditioner */ 683 return; 684 } 685 #endif 686 /* 687 * The following check is not documented in specs. A malicious 688 * party may be able to use IPv4 mapped addr to confuse tcp/udp stack 689 * and bypass security checks (act as if it was from 127.0.0.1 by using 690 * IPv6 src ::ffff:127.0.0.1). Be cautious. 691 * 692 * This check chokes if we are in an SIIT cloud. As none of BSDs 693 * support IPv4-less kernel compilation, we cannot support SIIT 694 * environment at all. So, it makes more sense for us to reject any 695 * malicious packets for non-SIIT environment, than try to do a 696 * partial support for SIIT environment. 697 */ 698 if (IN6_IS_ADDR_V4MAPPED(&ip6->ip6_src) || 699 IN6_IS_ADDR_V4MAPPED(&ip6->ip6_dst)) { 700 IP6STAT_INC(ip6s_badscope); 701 in6_ifstat_inc(rcvif, ifs6_in_addrerr); 702 goto bad; 703 } 704 #if 0 705 /* 706 * Reject packets with IPv4 compatible addresses (auto tunnel). 707 * 708 * The code forbids auto tunnel relay case in RFC1933 (the check is 709 * stronger than RFC1933). We may want to re-enable it if mech-xx 710 * is revised to forbid relaying case. 711 */ 712 if (IN6_IS_ADDR_V4COMPAT(&ip6->ip6_src) || 713 IN6_IS_ADDR_V4COMPAT(&ip6->ip6_dst)) { 714 IP6STAT_INC(ip6s_badscope); 715 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr); 716 goto bad; 717 } 718 #endif 719 /* 720 * Try to forward the packet, but if we fail continue. 721 * ip6_tryforward() does inbound and outbound packet firewall 722 * processing. If firewall has decided that destination becomes 723 * our local address, it sets M_FASTFWD_OURS flag. In this 724 * case skip another inbound firewall processing and update 725 * ip6 pointer. 726 */ 727 if (V_ip6_forwarding != 0 728 #if defined(IPSEC) || defined(IPSEC_SUPPORT) 729 && (!IPSEC_ENABLED(ipv6) || 730 IPSEC_CAPS(ipv6, m, IPSEC_CAP_OPERABLE) == 0) 731 #endif 732 ) { 733 if ((m = ip6_tryforward(m)) == NULL) 734 return; 735 if (m->m_flags & M_FASTFWD_OURS) { 736 ip6 = mtod(m, struct ip6_hdr *); 737 goto passin; 738 } 739 } 740 #if defined(IPSEC) || defined(IPSEC_SUPPORT) 741 /* 742 * Bypass packet filtering for packets previously handled by IPsec. 743 */ 744 if (IPSEC_ENABLED(ipv6) && 745 IPSEC_CAPS(ipv6, m, IPSEC_CAP_BYPASS_FILTER) != 0) 746 goto passin; 747 #endif 748 /* 749 * Run through list of hooks for input packets. 750 * 751 * NB: Beware of the destination address changing 752 * (e.g. by NAT rewriting). When this happens, 753 * tell ip6_forward to do the right thing. 754 */ 755 756 /* Jump over all PFIL processing if hooks are not active. */ 757 if (!PFIL_HOOKED(&V_inet6_pfil_hook)) 758 goto passin; 759 760 odst = ip6->ip6_dst; 761 if (pfil_run_hooks(&V_inet6_pfil_hook, &m, 762 m->m_pkthdr.rcvif, PFIL_IN, 0, NULL)) 763 return; 764 if (m == NULL) /* consumed by filter */ 765 return; 766 ip6 = mtod(m, struct ip6_hdr *); 767 srcrt = !IN6_ARE_ADDR_EQUAL(&odst, &ip6->ip6_dst); 768 if ((m->m_flags & (M_IP6_NEXTHOP | M_FASTFWD_OURS)) == M_IP6_NEXTHOP && 769 m_tag_find(m, PACKET_TAG_IPFORWARD, NULL) != NULL) { 770 /* 771 * Directly ship the packet on. This allows forwarding 772 * packets originally destined to us to some other directly 773 * connected host. 774 */ 775 ip6_forward(m, 1); 776 return; 777 } 778 779 passin: 780 /* 781 * Disambiguate address scope zones (if there is ambiguity). 782 * We first make sure that the original source or destination address 783 * is not in our internal form for scoped addresses. Such addresses 784 * are not necessarily invalid spec-wise, but we cannot accept them due 785 * to the usage conflict. 786 * in6_setscope() then also checks and rejects the cases where src or 787 * dst are the loopback address and the receiving interface 788 * is not loopback. 789 */ 790 if (in6_clearscope(&ip6->ip6_src) || in6_clearscope(&ip6->ip6_dst)) { 791 IP6STAT_INC(ip6s_badscope); /* XXX */ 792 goto bad; 793 } 794 if (in6_setscope(&ip6->ip6_src, rcvif, NULL) || 795 in6_setscope(&ip6->ip6_dst, rcvif, NULL)) { 796 IP6STAT_INC(ip6s_badscope); 797 goto bad; 798 } 799 if (m->m_flags & M_FASTFWD_OURS) { 800 m->m_flags &= ~M_FASTFWD_OURS; 801 ours = 1; 802 goto hbhcheck; 803 } 804 /* 805 * Multicast check. Assume packet is for us to avoid 806 * prematurely taking locks. 807 */ 808 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 809 ours = 1; 810 in6_ifstat_inc(rcvif, ifs6_in_mcast); 811 goto hbhcheck; 812 } 813 /* 814 * Unicast check 815 * XXX: For now we keep link-local IPv6 addresses with embedded 816 * scope zone id, therefore we use zero zoneid here. 817 */ 818 ia = in6ifa_ifwithaddr(&ip6->ip6_dst, 0 /* XXX */); 819 if (ia != NULL) { 820 if (ia->ia6_flags & IN6_IFF_NOTREADY) { 821 char ip6bufs[INET6_ADDRSTRLEN]; 822 char ip6bufd[INET6_ADDRSTRLEN]; 823 /* address is not ready, so discard the packet. */ 824 nd6log((LOG_INFO, 825 "ip6_input: packet to an unready address %s->%s\n", 826 ip6_sprintf(ip6bufs, &ip6->ip6_src), 827 ip6_sprintf(ip6bufd, &ip6->ip6_dst))); 828 ifa_free(&ia->ia_ifa); 829 goto bad; 830 } 831 /* Count the packet in the ip address stats */ 832 counter_u64_add(ia->ia_ifa.ifa_ipackets, 1); 833 counter_u64_add(ia->ia_ifa.ifa_ibytes, m->m_pkthdr.len); 834 ifa_free(&ia->ia_ifa); 835 ours = 1; 836 goto hbhcheck; 837 } 838 839 /* 840 * Now there is no reason to process the packet if it's not our own 841 * and we're not a router. 842 */ 843 if (!V_ip6_forwarding) { 844 IP6STAT_INC(ip6s_cantforward); 845 goto bad; 846 } 847 848 hbhcheck: 849 /* 850 * Process Hop-by-Hop options header if it's contained. 851 * m may be modified in ip6_hopopts_input(). 852 * If a JumboPayload option is included, plen will also be modified. 853 */ 854 plen = (u_int32_t)ntohs(ip6->ip6_plen); 855 if (ip6->ip6_nxt == IPPROTO_HOPOPTS) { 856 if (ip6_input_hbh(m, &plen, &rtalert, &off, &nxt, &ours) != 0) 857 return; 858 } else 859 nxt = ip6->ip6_nxt; 860 861 /* 862 * Use mbuf flags to propagate Router Alert option to 863 * ICMPv6 layer, as hop-by-hop options have been stripped. 864 */ 865 if (rtalert != ~0) 866 m->m_flags |= M_RTALERT_MLD; 867 868 /* 869 * Check that the amount of data in the buffers 870 * is as at least much as the IPv6 header would have us expect. 871 * Trim mbufs if longer than we expect. 872 * Drop packet if shorter than we expect. 873 */ 874 if (m->m_pkthdr.len - sizeof(struct ip6_hdr) < plen) { 875 IP6STAT_INC(ip6s_tooshort); 876 in6_ifstat_inc(rcvif, ifs6_in_truncated); 877 goto bad; 878 } 879 if (m->m_pkthdr.len > sizeof(struct ip6_hdr) + plen) { 880 if (m->m_len == m->m_pkthdr.len) { 881 m->m_len = sizeof(struct ip6_hdr) + plen; 882 m->m_pkthdr.len = sizeof(struct ip6_hdr) + plen; 883 } else 884 m_adj(m, sizeof(struct ip6_hdr) + plen - m->m_pkthdr.len); 885 } 886 887 /* 888 * Forward if desirable. 889 */ 890 if (V_ip6_mrouter && 891 IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 892 /* 893 * If we are acting as a multicast router, all 894 * incoming multicast packets are passed to the 895 * kernel-level multicast forwarding function. 896 * The packet is returned (relatively) intact; if 897 * ip6_mforward() returns a non-zero value, the packet 898 * must be discarded, else it may be accepted below. 899 * 900 * XXX TODO: Check hlim and multicast scope here to avoid 901 * unnecessarily calling into ip6_mforward(). 902 */ 903 if (ip6_mforward && ip6_mforward(ip6, rcvif, m)) { 904 IP6STAT_INC(ip6s_cantforward); 905 goto bad; 906 } 907 } else if (!ours) { 908 ip6_forward(m, srcrt); 909 return; 910 } 911 912 ip6 = mtod(m, struct ip6_hdr *); 913 914 /* 915 * Malicious party may be able to use IPv4 mapped addr to confuse 916 * tcp/udp stack and bypass security checks (act as if it was from 917 * 127.0.0.1 by using IPv6 src ::ffff:127.0.0.1). Be cautious. 918 * 919 * For SIIT end node behavior, you may want to disable the check. 920 * However, you will become vulnerable to attacks using IPv4 mapped 921 * source. 922 */ 923 if (IN6_IS_ADDR_V4MAPPED(&ip6->ip6_src) || 924 IN6_IS_ADDR_V4MAPPED(&ip6->ip6_dst)) { 925 IP6STAT_INC(ip6s_badscope); 926 in6_ifstat_inc(rcvif, ifs6_in_addrerr); 927 goto bad; 928 } 929 930 /* 931 * Tell launch routine the next header 932 */ 933 IP6STAT_INC(ip6s_delivered); 934 in6_ifstat_inc(rcvif, ifs6_in_deliver); 935 nest = 0; 936 937 while (nxt != IPPROTO_DONE) { 938 if (V_ip6_hdrnestlimit && (++nest > V_ip6_hdrnestlimit)) { 939 IP6STAT_INC(ip6s_toomanyhdr); 940 goto bad; 941 } 942 943 /* 944 * protection against faulty packet - there should be 945 * more sanity checks in header chain processing. 946 */ 947 if (m->m_pkthdr.len < off) { 948 IP6STAT_INC(ip6s_tooshort); 949 in6_ifstat_inc(rcvif, ifs6_in_truncated); 950 goto bad; 951 } 952 953 #if defined(IPSEC) || defined(IPSEC_SUPPORT) 954 if (IPSEC_ENABLED(ipv6)) { 955 if (IPSEC_INPUT(ipv6, m, off, nxt) != 0) 956 return; 957 } 958 #endif /* IPSEC */ 959 960 nxt = (*inet6sw[ip6_protox[nxt]].pr_input)(&m, &off, nxt); 961 } 962 return; 963 bad: 964 in6_ifstat_inc(rcvif, ifs6_in_discard); 965 if (m != NULL) 966 m_freem(m); 967 } 968 969 /* 970 * Hop-by-Hop options header processing. If a valid jumbo payload option is 971 * included, the real payload length will be stored in plenp. 972 * 973 * rtalertp - XXX: should be stored more smart way 974 */ 975 static int 976 ip6_hopopts_input(u_int32_t *plenp, u_int32_t *rtalertp, 977 struct mbuf **mp, int *offp) 978 { 979 struct mbuf *m = *mp; 980 int off = *offp, hbhlen; 981 struct ip6_hbh *hbh; 982 983 /* validation of the length of the header */ 984 #ifndef PULLDOWN_TEST 985 IP6_EXTHDR_CHECK(m, off, sizeof(*hbh), -1); 986 hbh = (struct ip6_hbh *)(mtod(m, caddr_t) + off); 987 hbhlen = (hbh->ip6h_len + 1) << 3; 988 989 IP6_EXTHDR_CHECK(m, off, hbhlen, -1); 990 hbh = (struct ip6_hbh *)(mtod(m, caddr_t) + off); 991 #else 992 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, 993 sizeof(struct ip6_hdr), sizeof(struct ip6_hbh)); 994 if (hbh == NULL) { 995 IP6STAT_INC(ip6s_tooshort); 996 return -1; 997 } 998 hbhlen = (hbh->ip6h_len + 1) << 3; 999 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, sizeof(struct ip6_hdr), 1000 hbhlen); 1001 if (hbh == NULL) { 1002 IP6STAT_INC(ip6s_tooshort); 1003 return -1; 1004 } 1005 #endif 1006 off += hbhlen; 1007 hbhlen -= sizeof(struct ip6_hbh); 1008 if (ip6_process_hopopts(m, (u_int8_t *)hbh + sizeof(struct ip6_hbh), 1009 hbhlen, rtalertp, plenp) < 0) 1010 return (-1); 1011 1012 *offp = off; 1013 *mp = m; 1014 return (0); 1015 } 1016 1017 /* 1018 * Search header for all Hop-by-hop options and process each option. 1019 * This function is separate from ip6_hopopts_input() in order to 1020 * handle a case where the sending node itself process its hop-by-hop 1021 * options header. In such a case, the function is called from ip6_output(). 1022 * 1023 * The function assumes that hbh header is located right after the IPv6 header 1024 * (RFC2460 p7), opthead is pointer into data content in m, and opthead to 1025 * opthead + hbhlen is located in contiguous memory region. 1026 */ 1027 int 1028 ip6_process_hopopts(struct mbuf *m, u_int8_t *opthead, int hbhlen, 1029 u_int32_t *rtalertp, u_int32_t *plenp) 1030 { 1031 struct ip6_hdr *ip6; 1032 int optlen = 0; 1033 u_int8_t *opt = opthead; 1034 u_int16_t rtalert_val; 1035 u_int32_t jumboplen; 1036 const int erroff = sizeof(struct ip6_hdr) + sizeof(struct ip6_hbh); 1037 1038 for (; hbhlen > 0; hbhlen -= optlen, opt += optlen) { 1039 switch (*opt) { 1040 case IP6OPT_PAD1: 1041 optlen = 1; 1042 break; 1043 case IP6OPT_PADN: 1044 if (hbhlen < IP6OPT_MINLEN) { 1045 IP6STAT_INC(ip6s_toosmall); 1046 goto bad; 1047 } 1048 optlen = *(opt + 1) + 2; 1049 break; 1050 case IP6OPT_ROUTER_ALERT: 1051 /* XXX may need check for alignment */ 1052 if (hbhlen < IP6OPT_RTALERT_LEN) { 1053 IP6STAT_INC(ip6s_toosmall); 1054 goto bad; 1055 } 1056 if (*(opt + 1) != IP6OPT_RTALERT_LEN - 2) { 1057 /* XXX stat */ 1058 icmp6_error(m, ICMP6_PARAM_PROB, 1059 ICMP6_PARAMPROB_HEADER, 1060 erroff + opt + 1 - opthead); 1061 return (-1); 1062 } 1063 optlen = IP6OPT_RTALERT_LEN; 1064 bcopy((caddr_t)(opt + 2), (caddr_t)&rtalert_val, 2); 1065 *rtalertp = ntohs(rtalert_val); 1066 break; 1067 case IP6OPT_JUMBO: 1068 /* XXX may need check for alignment */ 1069 if (hbhlen < IP6OPT_JUMBO_LEN) { 1070 IP6STAT_INC(ip6s_toosmall); 1071 goto bad; 1072 } 1073 if (*(opt + 1) != IP6OPT_JUMBO_LEN - 2) { 1074 /* XXX stat */ 1075 icmp6_error(m, ICMP6_PARAM_PROB, 1076 ICMP6_PARAMPROB_HEADER, 1077 erroff + opt + 1 - opthead); 1078 return (-1); 1079 } 1080 optlen = IP6OPT_JUMBO_LEN; 1081 1082 /* 1083 * IPv6 packets that have non 0 payload length 1084 * must not contain a jumbo payload option. 1085 */ 1086 ip6 = mtod(m, struct ip6_hdr *); 1087 if (ip6->ip6_plen) { 1088 IP6STAT_INC(ip6s_badoptions); 1089 icmp6_error(m, ICMP6_PARAM_PROB, 1090 ICMP6_PARAMPROB_HEADER, 1091 erroff + opt - opthead); 1092 return (-1); 1093 } 1094 1095 /* 1096 * We may see jumbolen in unaligned location, so 1097 * we'd need to perform bcopy(). 1098 */ 1099 bcopy(opt + 2, &jumboplen, sizeof(jumboplen)); 1100 jumboplen = (u_int32_t)htonl(jumboplen); 1101 1102 #if 1 1103 /* 1104 * if there are multiple jumbo payload options, 1105 * *plenp will be non-zero and the packet will be 1106 * rejected. 1107 * the behavior may need some debate in ipngwg - 1108 * multiple options does not make sense, however, 1109 * there's no explicit mention in specification. 1110 */ 1111 if (*plenp != 0) { 1112 IP6STAT_INC(ip6s_badoptions); 1113 icmp6_error(m, ICMP6_PARAM_PROB, 1114 ICMP6_PARAMPROB_HEADER, 1115 erroff + opt + 2 - opthead); 1116 return (-1); 1117 } 1118 #endif 1119 1120 /* 1121 * jumbo payload length must be larger than 65535. 1122 */ 1123 if (jumboplen <= IPV6_MAXPACKET) { 1124 IP6STAT_INC(ip6s_badoptions); 1125 icmp6_error(m, ICMP6_PARAM_PROB, 1126 ICMP6_PARAMPROB_HEADER, 1127 erroff + opt + 2 - opthead); 1128 return (-1); 1129 } 1130 *plenp = jumboplen; 1131 1132 break; 1133 default: /* unknown option */ 1134 if (hbhlen < IP6OPT_MINLEN) { 1135 IP6STAT_INC(ip6s_toosmall); 1136 goto bad; 1137 } 1138 optlen = ip6_unknown_opt(opt, m, 1139 erroff + opt - opthead); 1140 if (optlen == -1) 1141 return (-1); 1142 optlen += 2; 1143 break; 1144 } 1145 } 1146 1147 return (0); 1148 1149 bad: 1150 m_freem(m); 1151 return (-1); 1152 } 1153 1154 /* 1155 * Unknown option processing. 1156 * The third argument `off' is the offset from the IPv6 header to the option, 1157 * which is necessary if the IPv6 header the and option header and IPv6 header 1158 * is not contiguous in order to return an ICMPv6 error. 1159 */ 1160 int 1161 ip6_unknown_opt(u_int8_t *optp, struct mbuf *m, int off) 1162 { 1163 struct ip6_hdr *ip6; 1164 1165 switch (IP6OPT_TYPE(*optp)) { 1166 case IP6OPT_TYPE_SKIP: /* ignore the option */ 1167 return ((int)*(optp + 1)); 1168 case IP6OPT_TYPE_DISCARD: /* silently discard */ 1169 m_freem(m); 1170 return (-1); 1171 case IP6OPT_TYPE_FORCEICMP: /* send ICMP even if multicasted */ 1172 IP6STAT_INC(ip6s_badoptions); 1173 icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_OPTION, off); 1174 return (-1); 1175 case IP6OPT_TYPE_ICMP: /* send ICMP if not multicasted */ 1176 IP6STAT_INC(ip6s_badoptions); 1177 ip6 = mtod(m, struct ip6_hdr *); 1178 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) || 1179 (m->m_flags & (M_BCAST|M_MCAST))) 1180 m_freem(m); 1181 else 1182 icmp6_error(m, ICMP6_PARAM_PROB, 1183 ICMP6_PARAMPROB_OPTION, off); 1184 return (-1); 1185 } 1186 1187 m_freem(m); /* XXX: NOTREACHED */ 1188 return (-1); 1189 } 1190 1191 /* 1192 * Create the "control" list for this pcb. 1193 * These functions will not modify mbuf chain at all. 1194 * 1195 * With KAME mbuf chain restriction: 1196 * The routine will be called from upper layer handlers like tcp6_input(). 1197 * Thus the routine assumes that the caller (tcp6_input) have already 1198 * called IP6_EXTHDR_CHECK() and all the extension headers are located in the 1199 * very first mbuf on the mbuf chain. 1200 * 1201 * ip6_savecontrol_v4 will handle those options that are possible to be 1202 * set on a v4-mapped socket. 1203 * ip6_savecontrol will directly call ip6_savecontrol_v4 to handle those 1204 * options and handle the v6-only ones itself. 1205 */ 1206 struct mbuf ** 1207 ip6_savecontrol_v4(struct inpcb *inp, struct mbuf *m, struct mbuf **mp, 1208 int *v4only) 1209 { 1210 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1211 1212 #ifdef SO_TIMESTAMP 1213 if ((inp->inp_socket->so_options & SO_TIMESTAMP) != 0) { 1214 struct timeval tv; 1215 1216 microtime(&tv); 1217 *mp = sbcreatecontrol((caddr_t) &tv, sizeof(tv), 1218 SCM_TIMESTAMP, SOL_SOCKET); 1219 if (*mp) 1220 mp = &(*mp)->m_next; 1221 } 1222 #endif 1223 1224 #define IS2292(inp, x, y) (((inp)->inp_flags & IN6P_RFC2292) ? (x) : (y)) 1225 /* RFC 2292 sec. 5 */ 1226 if ((inp->inp_flags & IN6P_PKTINFO) != 0) { 1227 struct in6_pktinfo pi6; 1228 1229 if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) { 1230 #ifdef INET 1231 struct ip *ip; 1232 1233 ip = mtod(m, struct ip *); 1234 pi6.ipi6_addr.s6_addr32[0] = 0; 1235 pi6.ipi6_addr.s6_addr32[1] = 0; 1236 pi6.ipi6_addr.s6_addr32[2] = IPV6_ADDR_INT32_SMP; 1237 pi6.ipi6_addr.s6_addr32[3] = ip->ip_dst.s_addr; 1238 #else 1239 /* We won't hit this code */ 1240 bzero(&pi6.ipi6_addr, sizeof(struct in6_addr)); 1241 #endif 1242 } else { 1243 bcopy(&ip6->ip6_dst, &pi6.ipi6_addr, sizeof(struct in6_addr)); 1244 in6_clearscope(&pi6.ipi6_addr); /* XXX */ 1245 } 1246 pi6.ipi6_ifindex = 1247 (m && m->m_pkthdr.rcvif) ? m->m_pkthdr.rcvif->if_index : 0; 1248 1249 *mp = sbcreatecontrol((caddr_t) &pi6, 1250 sizeof(struct in6_pktinfo), 1251 IS2292(inp, IPV6_2292PKTINFO, IPV6_PKTINFO), IPPROTO_IPV6); 1252 if (*mp) 1253 mp = &(*mp)->m_next; 1254 } 1255 1256 if ((inp->inp_flags & IN6P_HOPLIMIT) != 0) { 1257 int hlim; 1258 1259 if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) { 1260 #ifdef INET 1261 struct ip *ip; 1262 1263 ip = mtod(m, struct ip *); 1264 hlim = ip->ip_ttl; 1265 #else 1266 /* We won't hit this code */ 1267 hlim = 0; 1268 #endif 1269 } else { 1270 hlim = ip6->ip6_hlim & 0xff; 1271 } 1272 *mp = sbcreatecontrol((caddr_t) &hlim, sizeof(int), 1273 IS2292(inp, IPV6_2292HOPLIMIT, IPV6_HOPLIMIT), 1274 IPPROTO_IPV6); 1275 if (*mp) 1276 mp = &(*mp)->m_next; 1277 } 1278 1279 if ((inp->inp_flags & IN6P_TCLASS) != 0) { 1280 int tclass; 1281 1282 if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) { 1283 #ifdef INET 1284 struct ip *ip; 1285 1286 ip = mtod(m, struct ip *); 1287 tclass = ip->ip_tos; 1288 #else 1289 /* We won't hit this code */ 1290 tclass = 0; 1291 #endif 1292 } else { 1293 u_int32_t flowinfo; 1294 1295 flowinfo = (u_int32_t)ntohl(ip6->ip6_flow & IPV6_FLOWINFO_MASK); 1296 flowinfo >>= 20; 1297 tclass = flowinfo & 0xff; 1298 } 1299 *mp = sbcreatecontrol((caddr_t) &tclass, sizeof(int), 1300 IPV6_TCLASS, IPPROTO_IPV6); 1301 if (*mp) 1302 mp = &(*mp)->m_next; 1303 } 1304 1305 if (v4only != NULL) { 1306 if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) { 1307 *v4only = 1; 1308 } else { 1309 *v4only = 0; 1310 } 1311 } 1312 1313 return (mp); 1314 } 1315 1316 void 1317 ip6_savecontrol(struct inpcb *in6p, struct mbuf *m, struct mbuf **mp) 1318 { 1319 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1320 int v4only = 0; 1321 1322 mp = ip6_savecontrol_v4(in6p, m, mp, &v4only); 1323 if (v4only) 1324 return; 1325 1326 /* 1327 * IPV6_HOPOPTS socket option. Recall that we required super-user 1328 * privilege for the option (see ip6_ctloutput), but it might be too 1329 * strict, since there might be some hop-by-hop options which can be 1330 * returned to normal user. 1331 * See also RFC 2292 section 6 (or RFC 3542 section 8). 1332 */ 1333 if ((in6p->inp_flags & IN6P_HOPOPTS) != 0) { 1334 /* 1335 * Check if a hop-by-hop options header is contatined in the 1336 * received packet, and if so, store the options as ancillary 1337 * data. Note that a hop-by-hop options header must be 1338 * just after the IPv6 header, which is assured through the 1339 * IPv6 input processing. 1340 */ 1341 if (ip6->ip6_nxt == IPPROTO_HOPOPTS) { 1342 struct ip6_hbh *hbh; 1343 int hbhlen = 0; 1344 #ifdef PULLDOWN_TEST 1345 struct mbuf *ext; 1346 #endif 1347 1348 #ifndef PULLDOWN_TEST 1349 hbh = (struct ip6_hbh *)(ip6 + 1); 1350 hbhlen = (hbh->ip6h_len + 1) << 3; 1351 #else 1352 ext = ip6_pullexthdr(m, sizeof(struct ip6_hdr), 1353 ip6->ip6_nxt); 1354 if (ext == NULL) { 1355 IP6STAT_INC(ip6s_tooshort); 1356 return; 1357 } 1358 hbh = mtod(ext, struct ip6_hbh *); 1359 hbhlen = (hbh->ip6h_len + 1) << 3; 1360 if (hbhlen != ext->m_len) { 1361 m_freem(ext); 1362 IP6STAT_INC(ip6s_tooshort); 1363 return; 1364 } 1365 #endif 1366 1367 /* 1368 * XXX: We copy the whole header even if a 1369 * jumbo payload option is included, the option which 1370 * is to be removed before returning according to 1371 * RFC2292. 1372 * Note: this constraint is removed in RFC3542 1373 */ 1374 *mp = sbcreatecontrol((caddr_t)hbh, hbhlen, 1375 IS2292(in6p, IPV6_2292HOPOPTS, IPV6_HOPOPTS), 1376 IPPROTO_IPV6); 1377 if (*mp) 1378 mp = &(*mp)->m_next; 1379 #ifdef PULLDOWN_TEST 1380 m_freem(ext); 1381 #endif 1382 } 1383 } 1384 1385 if ((in6p->inp_flags & (IN6P_RTHDR | IN6P_DSTOPTS)) != 0) { 1386 int nxt = ip6->ip6_nxt, off = sizeof(struct ip6_hdr); 1387 1388 /* 1389 * Search for destination options headers or routing 1390 * header(s) through the header chain, and stores each 1391 * header as ancillary data. 1392 * Note that the order of the headers remains in 1393 * the chain of ancillary data. 1394 */ 1395 while (1) { /* is explicit loop prevention necessary? */ 1396 struct ip6_ext *ip6e = NULL; 1397 int elen; 1398 #ifdef PULLDOWN_TEST 1399 struct mbuf *ext = NULL; 1400 #endif 1401 1402 /* 1403 * if it is not an extension header, don't try to 1404 * pull it from the chain. 1405 */ 1406 switch (nxt) { 1407 case IPPROTO_DSTOPTS: 1408 case IPPROTO_ROUTING: 1409 case IPPROTO_HOPOPTS: 1410 case IPPROTO_AH: /* is it possible? */ 1411 break; 1412 default: 1413 goto loopend; 1414 } 1415 1416 #ifndef PULLDOWN_TEST 1417 if (off + sizeof(*ip6e) > m->m_len) 1418 goto loopend; 1419 ip6e = (struct ip6_ext *)(mtod(m, caddr_t) + off); 1420 if (nxt == IPPROTO_AH) 1421 elen = (ip6e->ip6e_len + 2) << 2; 1422 else 1423 elen = (ip6e->ip6e_len + 1) << 3; 1424 if (off + elen > m->m_len) 1425 goto loopend; 1426 #else 1427 ext = ip6_pullexthdr(m, off, nxt); 1428 if (ext == NULL) { 1429 IP6STAT_INC(ip6s_tooshort); 1430 return; 1431 } 1432 ip6e = mtod(ext, struct ip6_ext *); 1433 if (nxt == IPPROTO_AH) 1434 elen = (ip6e->ip6e_len + 2) << 2; 1435 else 1436 elen = (ip6e->ip6e_len + 1) << 3; 1437 if (elen != ext->m_len) { 1438 m_freem(ext); 1439 IP6STAT_INC(ip6s_tooshort); 1440 return; 1441 } 1442 #endif 1443 1444 switch (nxt) { 1445 case IPPROTO_DSTOPTS: 1446 if (!(in6p->inp_flags & IN6P_DSTOPTS)) 1447 break; 1448 1449 *mp = sbcreatecontrol((caddr_t)ip6e, elen, 1450 IS2292(in6p, 1451 IPV6_2292DSTOPTS, IPV6_DSTOPTS), 1452 IPPROTO_IPV6); 1453 if (*mp) 1454 mp = &(*mp)->m_next; 1455 break; 1456 case IPPROTO_ROUTING: 1457 if (!(in6p->inp_flags & IN6P_RTHDR)) 1458 break; 1459 1460 *mp = sbcreatecontrol((caddr_t)ip6e, elen, 1461 IS2292(in6p, IPV6_2292RTHDR, IPV6_RTHDR), 1462 IPPROTO_IPV6); 1463 if (*mp) 1464 mp = &(*mp)->m_next; 1465 break; 1466 case IPPROTO_HOPOPTS: 1467 case IPPROTO_AH: /* is it possible? */ 1468 break; 1469 1470 default: 1471 /* 1472 * other cases have been filtered in the above. 1473 * none will visit this case. here we supply 1474 * the code just in case (nxt overwritten or 1475 * other cases). 1476 */ 1477 #ifdef PULLDOWN_TEST 1478 m_freem(ext); 1479 #endif 1480 goto loopend; 1481 1482 } 1483 1484 /* proceed with the next header. */ 1485 off += elen; 1486 nxt = ip6e->ip6e_nxt; 1487 ip6e = NULL; 1488 #ifdef PULLDOWN_TEST 1489 m_freem(ext); 1490 ext = NULL; 1491 #endif 1492 } 1493 loopend: 1494 ; 1495 } 1496 1497 if (in6p->inp_flags2 & INP_RECVFLOWID) { 1498 uint32_t flowid, flow_type; 1499 1500 flowid = m->m_pkthdr.flowid; 1501 flow_type = M_HASHTYPE_GET(m); 1502 1503 /* 1504 * XXX should handle the failure of one or the 1505 * other - don't populate both? 1506 */ 1507 *mp = sbcreatecontrol((caddr_t) &flowid, 1508 sizeof(uint32_t), IPV6_FLOWID, IPPROTO_IPV6); 1509 if (*mp) 1510 mp = &(*mp)->m_next; 1511 *mp = sbcreatecontrol((caddr_t) &flow_type, 1512 sizeof(uint32_t), IPV6_FLOWTYPE, IPPROTO_IPV6); 1513 if (*mp) 1514 mp = &(*mp)->m_next; 1515 } 1516 1517 #ifdef RSS 1518 if (in6p->inp_flags2 & INP_RECVRSSBUCKETID) { 1519 uint32_t flowid, flow_type; 1520 uint32_t rss_bucketid; 1521 1522 flowid = m->m_pkthdr.flowid; 1523 flow_type = M_HASHTYPE_GET(m); 1524 1525 if (rss_hash2bucket(flowid, flow_type, &rss_bucketid) == 0) { 1526 *mp = sbcreatecontrol((caddr_t) &rss_bucketid, 1527 sizeof(uint32_t), IPV6_RSSBUCKETID, IPPROTO_IPV6); 1528 if (*mp) 1529 mp = &(*mp)->m_next; 1530 } 1531 } 1532 #endif 1533 1534 } 1535 #undef IS2292 1536 1537 void 1538 ip6_notify_pmtu(struct inpcb *inp, struct sockaddr_in6 *dst, u_int32_t mtu) 1539 { 1540 struct socket *so; 1541 struct mbuf *m_mtu; 1542 struct ip6_mtuinfo mtuctl; 1543 1544 KASSERT(inp != NULL, ("%s: inp == NULL", __func__)); 1545 /* 1546 * Notify the error by sending IPV6_PATHMTU ancillary data if 1547 * application wanted to know the MTU value. 1548 * NOTE: we notify disconnected sockets, because some udp 1549 * applications keep sending sockets disconnected. 1550 * NOTE: our implementation doesn't notify connected sockets that has 1551 * foreign address that is different than given destination addresses 1552 * (this is permitted by RFC 3542). 1553 */ 1554 if ((inp->inp_flags & IN6P_MTU) == 0 || ( 1555 !IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr) && 1556 !IN6_ARE_ADDR_EQUAL(&inp->in6p_faddr, &dst->sin6_addr))) 1557 return; 1558 1559 mtuctl.ip6m_mtu = mtu; 1560 mtuctl.ip6m_addr = *dst; 1561 if (sa6_recoverscope(&mtuctl.ip6m_addr)) 1562 return; 1563 1564 if ((m_mtu = sbcreatecontrol((caddr_t)&mtuctl, sizeof(mtuctl), 1565 IPV6_PATHMTU, IPPROTO_IPV6)) == NULL) 1566 return; 1567 1568 so = inp->inp_socket; 1569 if (sbappendaddr(&so->so_rcv, (struct sockaddr *)dst, NULL, m_mtu) 1570 == 0) { 1571 m_freem(m_mtu); 1572 /* XXX: should count statistics */ 1573 } else 1574 sorwakeup(so); 1575 } 1576 1577 #ifdef PULLDOWN_TEST 1578 /* 1579 * pull single extension header from mbuf chain. returns single mbuf that 1580 * contains the result, or NULL on error. 1581 */ 1582 static struct mbuf * 1583 ip6_pullexthdr(struct mbuf *m, size_t off, int nxt) 1584 { 1585 struct ip6_ext ip6e; 1586 size_t elen; 1587 struct mbuf *n; 1588 1589 #ifdef DIAGNOSTIC 1590 switch (nxt) { 1591 case IPPROTO_DSTOPTS: 1592 case IPPROTO_ROUTING: 1593 case IPPROTO_HOPOPTS: 1594 case IPPROTO_AH: /* is it possible? */ 1595 break; 1596 default: 1597 printf("ip6_pullexthdr: invalid nxt=%d\n", nxt); 1598 } 1599 #endif 1600 1601 m_copydata(m, off, sizeof(ip6e), (caddr_t)&ip6e); 1602 if (nxt == IPPROTO_AH) 1603 elen = (ip6e.ip6e_len + 2) << 2; 1604 else 1605 elen = (ip6e.ip6e_len + 1) << 3; 1606 1607 if (elen > MLEN) 1608 n = m_getcl(M_NOWAIT, MT_DATA, 0); 1609 else 1610 n = m_get(M_NOWAIT, MT_DATA); 1611 if (n == NULL) 1612 return NULL; 1613 1614 m_copydata(m, off, elen, mtod(n, caddr_t)); 1615 n->m_len = elen; 1616 return n; 1617 } 1618 #endif 1619 1620 /* 1621 * Get pointer to the previous header followed by the header 1622 * currently processed. 1623 */ 1624 int 1625 ip6_get_prevhdr(const struct mbuf *m, int off) 1626 { 1627 struct ip6_ext ip6e; 1628 struct ip6_hdr *ip6; 1629 int len, nlen, nxt; 1630 1631 if (off == sizeof(struct ip6_hdr)) 1632 return (offsetof(struct ip6_hdr, ip6_nxt)); 1633 if (off < sizeof(struct ip6_hdr)) 1634 panic("%s: off < sizeof(struct ip6_hdr)", __func__); 1635 1636 ip6 = mtod(m, struct ip6_hdr *); 1637 nxt = ip6->ip6_nxt; 1638 len = sizeof(struct ip6_hdr); 1639 nlen = 0; 1640 while (len < off) { 1641 m_copydata(m, len, sizeof(ip6e), (caddr_t)&ip6e); 1642 switch (nxt) { 1643 case IPPROTO_FRAGMENT: 1644 nlen = sizeof(struct ip6_frag); 1645 break; 1646 case IPPROTO_AH: 1647 nlen = (ip6e.ip6e_len + 2) << 2; 1648 break; 1649 default: 1650 nlen = (ip6e.ip6e_len + 1) << 3; 1651 } 1652 len += nlen; 1653 nxt = ip6e.ip6e_nxt; 1654 } 1655 return (len - nlen); 1656 } 1657 1658 /* 1659 * get next header offset. m will be retained. 1660 */ 1661 int 1662 ip6_nexthdr(const struct mbuf *m, int off, int proto, int *nxtp) 1663 { 1664 struct ip6_hdr ip6; 1665 struct ip6_ext ip6e; 1666 struct ip6_frag fh; 1667 1668 /* just in case */ 1669 if (m == NULL) 1670 panic("ip6_nexthdr: m == NULL"); 1671 if ((m->m_flags & M_PKTHDR) == 0 || m->m_pkthdr.len < off) 1672 return -1; 1673 1674 switch (proto) { 1675 case IPPROTO_IPV6: 1676 if (m->m_pkthdr.len < off + sizeof(ip6)) 1677 return -1; 1678 m_copydata(m, off, sizeof(ip6), (caddr_t)&ip6); 1679 if (nxtp) 1680 *nxtp = ip6.ip6_nxt; 1681 off += sizeof(ip6); 1682 return off; 1683 1684 case IPPROTO_FRAGMENT: 1685 /* 1686 * terminate parsing if it is not the first fragment, 1687 * it does not make sense to parse through it. 1688 */ 1689 if (m->m_pkthdr.len < off + sizeof(fh)) 1690 return -1; 1691 m_copydata(m, off, sizeof(fh), (caddr_t)&fh); 1692 /* IP6F_OFF_MASK = 0xfff8(BigEndian), 0xf8ff(LittleEndian) */ 1693 if (fh.ip6f_offlg & IP6F_OFF_MASK) 1694 return -1; 1695 if (nxtp) 1696 *nxtp = fh.ip6f_nxt; 1697 off += sizeof(struct ip6_frag); 1698 return off; 1699 1700 case IPPROTO_AH: 1701 if (m->m_pkthdr.len < off + sizeof(ip6e)) 1702 return -1; 1703 m_copydata(m, off, sizeof(ip6e), (caddr_t)&ip6e); 1704 if (nxtp) 1705 *nxtp = ip6e.ip6e_nxt; 1706 off += (ip6e.ip6e_len + 2) << 2; 1707 return off; 1708 1709 case IPPROTO_HOPOPTS: 1710 case IPPROTO_ROUTING: 1711 case IPPROTO_DSTOPTS: 1712 if (m->m_pkthdr.len < off + sizeof(ip6e)) 1713 return -1; 1714 m_copydata(m, off, sizeof(ip6e), (caddr_t)&ip6e); 1715 if (nxtp) 1716 *nxtp = ip6e.ip6e_nxt; 1717 off += (ip6e.ip6e_len + 1) << 3; 1718 return off; 1719 1720 case IPPROTO_NONE: 1721 case IPPROTO_ESP: 1722 case IPPROTO_IPCOMP: 1723 /* give up */ 1724 return -1; 1725 1726 default: 1727 return -1; 1728 } 1729 1730 /* NOTREACHED */ 1731 } 1732 1733 /* 1734 * get offset for the last header in the chain. m will be kept untainted. 1735 */ 1736 int 1737 ip6_lasthdr(const struct mbuf *m, int off, int proto, int *nxtp) 1738 { 1739 int newoff; 1740 int nxt; 1741 1742 if (!nxtp) { 1743 nxt = -1; 1744 nxtp = &nxt; 1745 } 1746 while (1) { 1747 newoff = ip6_nexthdr(m, off, proto, nxtp); 1748 if (newoff < 0) 1749 return off; 1750 else if (newoff < off) 1751 return -1; /* invalid */ 1752 else if (newoff == off) 1753 return newoff; 1754 1755 off = newoff; 1756 proto = *nxtp; 1757 } 1758 } 1759 1760 /* 1761 * System control for IP6 1762 */ 1763 1764 u_char inet6ctlerrmap[PRC_NCMDS] = { 1765 0, 0, 0, 0, 1766 0, EMSGSIZE, EHOSTDOWN, EHOSTUNREACH, 1767 EHOSTUNREACH, EHOSTUNREACH, ECONNREFUSED, ECONNREFUSED, 1768 EMSGSIZE, EHOSTUNREACH, 0, 0, 1769 0, 0, EHOSTUNREACH, 0, 1770 ENOPROTOOPT, ECONNREFUSED 1771 };
Cache object: c90e8fb9024e084f8266e4b006fab86e
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