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("$FreeBSD$"); 65 66 #include "opt_inet.h" 67 #include "opt_inet6.h" 68 #include "opt_ipfw.h" 69 #include "opt_ipsec.h" 70 #include "opt_route.h" 71 #include "opt_rss.h" 72 73 #include <sys/param.h> 74 #include <sys/systm.h> 75 #include <sys/hhook.h> 76 #include <sys/malloc.h> 77 #include <sys/mbuf.h> 78 #include <sys/proc.h> 79 #include <sys/domain.h> 80 #include <sys/protosw.h> 81 #include <sys/sdt.h> 82 #include <sys/socket.h> 83 #include <sys/socketvar.h> 84 #include <sys/errno.h> 85 #include <sys/time.h> 86 #include <sys/kernel.h> 87 #include <sys/lock.h> 88 #include <sys/rmlock.h> 89 #include <sys/syslog.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/nd6.h> 118 #include <netinet6/in6_rss.h> 119 120 #ifdef IPSEC 121 #include <netipsec/ipsec.h> 122 #include <netinet6/ip6_ipsec.h> 123 #include <netipsec/ipsec6.h> 124 #endif /* IPSEC */ 125 126 #include <netinet6/ip6protosw.h> 127 128 extern struct domain inet6domain; 129 130 u_char ip6_protox[IPPROTO_MAX]; 131 VNET_DEFINE(struct in6_ifaddrhead, in6_ifaddrhead); 132 VNET_DEFINE(struct in6_ifaddrlisthead *, in6_ifaddrhashtbl); 133 VNET_DEFINE(u_long, in6_ifaddrhmask); 134 135 static struct netisr_handler ip6_nh = { 136 .nh_name = "ip6", 137 .nh_handler = ip6_input, 138 .nh_proto = NETISR_IPV6, 139 #ifdef RSS 140 .nh_m2cpuid = rss_soft_m2cpuid_v6, 141 .nh_policy = NETISR_POLICY_CPU, 142 .nh_dispatch = NETISR_DISPATCH_HYBRID, 143 #else 144 .nh_policy = NETISR_POLICY_FLOW, 145 #endif 146 }; 147 148 #ifdef RSS 149 static struct netisr_handler ip6_direct_nh = { 150 .nh_name = "ip6_direct", 151 .nh_handler = ip6_direct_input, 152 .nh_proto = NETISR_IPV6_DIRECT, 153 .nh_m2cpuid = rss_soft_m2cpuid_v6, 154 .nh_policy = NETISR_POLICY_CPU, 155 .nh_dispatch = NETISR_DISPATCH_HYBRID, 156 }; 157 #endif 158 159 VNET_DEFINE(struct pfil_head, inet6_pfil_hook); 160 161 VNET_PCPUSTAT_DEFINE(struct ip6stat, ip6stat); 162 VNET_PCPUSTAT_SYSINIT(ip6stat); 163 #ifdef VIMAGE 164 VNET_PCPUSTAT_SYSUNINIT(ip6stat); 165 #endif /* VIMAGE */ 166 167 struct rmlock in6_ifaddr_lock; 168 RM_SYSINIT(in6_ifaddr_lock, &in6_ifaddr_lock, "in6_ifaddr_lock"); 169 170 static int ip6_hopopts_input(u_int32_t *, u_int32_t *, struct mbuf **, int *); 171 #ifdef PULLDOWN_TEST 172 static struct mbuf *ip6_pullexthdr(struct mbuf *, size_t, int); 173 #endif 174 175 /* 176 * IP6 initialization: fill in IP6 protocol switch table. 177 * All protocols not implemented in kernel go to raw IP6 protocol handler. 178 */ 179 void 180 ip6_init(void) 181 { 182 struct protosw *pr; 183 int i; 184 185 TUNABLE_INT_FETCH("net.inet6.ip6.auto_linklocal", 186 &V_ip6_auto_linklocal); 187 TUNABLE_INT_FETCH("net.inet6.ip6.accept_rtadv", &V_ip6_accept_rtadv); 188 TUNABLE_INT_FETCH("net.inet6.ip6.no_radr", &V_ip6_no_radr); 189 190 TAILQ_INIT(&V_in6_ifaddrhead); 191 V_in6_ifaddrhashtbl = hashinit(IN6ADDR_NHASH, M_IFADDR, 192 &V_in6_ifaddrhmask); 193 194 /* Initialize packet filter hooks. */ 195 V_inet6_pfil_hook.ph_type = PFIL_TYPE_AF; 196 V_inet6_pfil_hook.ph_af = AF_INET6; 197 if ((i = pfil_head_register(&V_inet6_pfil_hook)) != 0) 198 printf("%s: WARNING: unable to register pfil hook, " 199 "error %d\n", __func__, i); 200 201 if (hhook_head_register(HHOOK_TYPE_IPSEC_IN, AF_INET6, 202 &V_ipsec_hhh_in[HHOOK_IPSEC_INET6], 203 HHOOK_WAITOK | HHOOK_HEADISINVNET) != 0) 204 printf("%s: WARNING: unable to register input helper hook\n", 205 __func__); 206 if (hhook_head_register(HHOOK_TYPE_IPSEC_OUT, AF_INET6, 207 &V_ipsec_hhh_out[HHOOK_IPSEC_INET6], 208 HHOOK_WAITOK | HHOOK_HEADISINVNET) != 0) 209 printf("%s: WARNING: unable to register output helper hook\n", 210 __func__); 211 212 scope6_init(); 213 addrsel_policy_init(); 214 nd6_init(); 215 frag6_init(); 216 217 V_ip6_desync_factor = arc4random() % MAX_TEMP_DESYNC_FACTOR; 218 219 /* Skip global initialization stuff for non-default instances. */ 220 if (!IS_DEFAULT_VNET(curvnet)) 221 return; 222 223 pr = pffindproto(PF_INET6, IPPROTO_RAW, SOCK_RAW); 224 if (pr == NULL) 225 panic("ip6_init"); 226 227 /* Initialize the entire ip6_protox[] array to IPPROTO_RAW. */ 228 for (i = 0; i < IPPROTO_MAX; i++) 229 ip6_protox[i] = pr - inet6sw; 230 /* 231 * Cycle through IP protocols and put them into the appropriate place 232 * in ip6_protox[]. 233 */ 234 for (pr = inet6domain.dom_protosw; 235 pr < inet6domain.dom_protoswNPROTOSW; pr++) 236 if (pr->pr_domain->dom_family == PF_INET6 && 237 pr->pr_protocol && pr->pr_protocol != IPPROTO_RAW) { 238 /* Be careful to only index valid IP protocols. */ 239 if (pr->pr_protocol < IPPROTO_MAX) 240 ip6_protox[pr->pr_protocol] = pr - inet6sw; 241 } 242 243 netisr_register(&ip6_nh); 244 #ifdef RSS 245 netisr_register(&ip6_direct_nh); 246 #endif 247 } 248 249 /* 250 * The protocol to be inserted into ip6_protox[] must be already registered 251 * in inet6sw[], either statically or through pf_proto_register(). 252 */ 253 int 254 ip6proto_register(short ip6proto) 255 { 256 struct protosw *pr; 257 258 /* Sanity checks. */ 259 if (ip6proto <= 0 || ip6proto >= IPPROTO_MAX) 260 return (EPROTONOSUPPORT); 261 262 /* 263 * The protocol slot must not be occupied by another protocol 264 * already. An index pointing to IPPROTO_RAW is unused. 265 */ 266 pr = pffindproto(PF_INET6, IPPROTO_RAW, SOCK_RAW); 267 if (pr == NULL) 268 return (EPFNOSUPPORT); 269 if (ip6_protox[ip6proto] != pr - inet6sw) /* IPPROTO_RAW */ 270 return (EEXIST); 271 272 /* 273 * Find the protocol position in inet6sw[] and set the index. 274 */ 275 for (pr = inet6domain.dom_protosw; 276 pr < inet6domain.dom_protoswNPROTOSW; pr++) { 277 if (pr->pr_domain->dom_family == PF_INET6 && 278 pr->pr_protocol && pr->pr_protocol == ip6proto) { 279 ip6_protox[pr->pr_protocol] = pr - inet6sw; 280 return (0); 281 } 282 } 283 return (EPROTONOSUPPORT); 284 } 285 286 int 287 ip6proto_unregister(short ip6proto) 288 { 289 struct protosw *pr; 290 291 /* Sanity checks. */ 292 if (ip6proto <= 0 || ip6proto >= IPPROTO_MAX) 293 return (EPROTONOSUPPORT); 294 295 /* Check if the protocol was indeed registered. */ 296 pr = pffindproto(PF_INET6, IPPROTO_RAW, SOCK_RAW); 297 if (pr == NULL) 298 return (EPFNOSUPPORT); 299 if (ip6_protox[ip6proto] == pr - inet6sw) /* IPPROTO_RAW */ 300 return (ENOENT); 301 302 /* Reset the protocol slot to IPPROTO_RAW. */ 303 ip6_protox[ip6proto] = pr - inet6sw; 304 return (0); 305 } 306 307 #ifdef VIMAGE 308 static void 309 ip6_destroy(void *unused __unused) 310 { 311 int error; 312 313 if ((error = pfil_head_unregister(&V_inet6_pfil_hook)) != 0) 314 printf("%s: WARNING: unable to unregister pfil hook, " 315 "error %d\n", __func__, error); 316 error = hhook_head_deregister(V_ipsec_hhh_in[HHOOK_IPSEC_INET6]); 317 if (error != 0) { 318 printf("%s: WARNING: unable to deregister input helper hook " 319 "type HHOOK_TYPE_IPSEC_IN, id HHOOK_IPSEC_INET6: " 320 "error %d returned\n", __func__, error); 321 } 322 error = hhook_head_deregister(V_ipsec_hhh_out[HHOOK_IPSEC_INET6]); 323 if (error != 0) { 324 printf("%s: WARNING: unable to deregister output helper hook " 325 "type HHOOK_TYPE_IPSEC_OUT, id HHOOK_IPSEC_INET6: " 326 "error %d returned\n", __func__, error); 327 } 328 hashdestroy(V_in6_ifaddrhashtbl, M_IFADDR, V_in6_ifaddrhmask); 329 nd6_destroy(); 330 in6_ifattach_destroy(); 331 } 332 333 VNET_SYSUNINIT(inet6, SI_SUB_PROTO_DOMAIN, SI_ORDER_THIRD, ip6_destroy, NULL); 334 #endif 335 336 static int 337 ip6_input_hbh(struct mbuf *m, uint32_t *plen, uint32_t *rtalert, int *off, 338 int *nxt, int *ours) 339 { 340 struct ip6_hdr *ip6; 341 struct ip6_hbh *hbh; 342 343 if (ip6_hopopts_input(plen, rtalert, &m, off)) { 344 #if 0 /*touches NULL pointer*/ 345 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard); 346 #endif 347 goto out; /* m have already been freed */ 348 } 349 350 /* adjust pointer */ 351 ip6 = mtod(m, struct ip6_hdr *); 352 353 /* 354 * if the payload length field is 0 and the next header field 355 * indicates Hop-by-Hop Options header, then a Jumbo Payload 356 * option MUST be included. 357 */ 358 if (ip6->ip6_plen == 0 && *plen == 0) { 359 /* 360 * Note that if a valid jumbo payload option is 361 * contained, ip6_hopopts_input() must set a valid 362 * (non-zero) payload length to the variable plen. 363 */ 364 IP6STAT_INC(ip6s_badoptions); 365 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard); 366 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_hdrerr); 367 icmp6_error(m, ICMP6_PARAM_PROB, 368 ICMP6_PARAMPROB_HEADER, 369 (caddr_t)&ip6->ip6_plen - (caddr_t)ip6); 370 goto out; 371 } 372 #ifndef PULLDOWN_TEST 373 /* ip6_hopopts_input() ensures that mbuf is contiguous */ 374 hbh = (struct ip6_hbh *)(ip6 + 1); 375 #else 376 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, sizeof(struct ip6_hdr), 377 sizeof(struct ip6_hbh)); 378 if (hbh == NULL) { 379 IP6STAT_INC(ip6s_tooshort); 380 goto out; 381 } 382 #endif 383 *nxt = hbh->ip6h_nxt; 384 385 /* 386 * If we are acting as a router and the packet contains a 387 * router alert option, see if we know the option value. 388 * Currently, we only support the option value for MLD, in which 389 * case we should pass the packet to the multicast routing 390 * daemon. 391 */ 392 if (*rtalert != ~0) { 393 switch (*rtalert) { 394 case IP6OPT_RTALERT_MLD: 395 if (V_ip6_forwarding) 396 *ours = 1; 397 break; 398 default: 399 /* 400 * RFC2711 requires unrecognized values must be 401 * silently ignored. 402 */ 403 break; 404 } 405 } 406 407 return (0); 408 409 out: 410 return (1); 411 } 412 413 #ifdef RSS 414 /* 415 * IPv6 direct input routine. 416 * 417 * This is called when reinjecting completed fragments where 418 * all of the previous checking and book-keeping has been done. 419 */ 420 void 421 ip6_direct_input(struct mbuf *m) 422 { 423 int off, nxt; 424 int nest; 425 struct m_tag *mtag; 426 struct ip6_direct_ctx *ip6dc; 427 428 mtag = m_tag_locate(m, MTAG_ABI_IPV6, IPV6_TAG_DIRECT, NULL); 429 KASSERT(mtag != NULL, ("Reinjected packet w/o direct ctx tag!")); 430 431 ip6dc = (struct ip6_direct_ctx *)(mtag + 1); 432 nxt = ip6dc->ip6dc_nxt; 433 off = ip6dc->ip6dc_off; 434 435 nest = 0; 436 437 m_tag_delete(m, mtag); 438 439 while (nxt != IPPROTO_DONE) { 440 if (V_ip6_hdrnestlimit && (++nest > V_ip6_hdrnestlimit)) { 441 IP6STAT_INC(ip6s_toomanyhdr); 442 goto bad; 443 } 444 445 /* 446 * protection against faulty packet - there should be 447 * more sanity checks in header chain processing. 448 */ 449 if (m->m_pkthdr.len < off) { 450 IP6STAT_INC(ip6s_tooshort); 451 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_truncated); 452 goto bad; 453 } 454 455 #ifdef IPSEC 456 /* 457 * enforce IPsec policy checking if we are seeing last header. 458 * note that we do not visit this with protocols with pcb layer 459 * code - like udp/tcp/raw ip. 460 */ 461 if (ip6_ipsec_input(m, nxt)) 462 goto bad; 463 #endif /* IPSEC */ 464 465 nxt = (*inet6sw[ip6_protox[nxt]].pr_input)(&m, &off, nxt); 466 } 467 return; 468 bad: 469 m_freem(m); 470 } 471 #endif 472 473 void 474 ip6_input(struct mbuf *m) 475 { 476 struct in6_addr odst; 477 struct ip6_hdr *ip6; 478 struct in6_ifaddr *ia; 479 u_int32_t plen; 480 u_int32_t rtalert = ~0; 481 int off = sizeof(struct ip6_hdr), nest; 482 int nxt, ours = 0; 483 int srcrt = 0; 484 485 #ifdef IPSEC 486 /* 487 * should the inner packet be considered authentic? 488 * see comment in ah4_input(). 489 * NB: m cannot be NULL when passed to the input routine 490 */ 491 492 m->m_flags &= ~M_AUTHIPHDR; 493 m->m_flags &= ~M_AUTHIPDGM; 494 495 #endif /* IPSEC */ 496 497 if (m->m_flags & M_FASTFWD_OURS) { 498 /* 499 * Firewall changed destination to local. 500 */ 501 m->m_flags &= ~M_FASTFWD_OURS; 502 ours = 1; 503 ip6 = mtod(m, struct ip6_hdr *); 504 goto hbhcheck; 505 } 506 507 /* 508 * mbuf statistics 509 */ 510 if (m->m_flags & M_EXT) { 511 if (m->m_next) 512 IP6STAT_INC(ip6s_mext2m); 513 else 514 IP6STAT_INC(ip6s_mext1); 515 } else { 516 if (m->m_next) { 517 if (m->m_flags & M_LOOP) { 518 IP6STAT_INC(ip6s_m2m[V_loif->if_index]); 519 } else if (m->m_pkthdr.rcvif->if_index < IP6S_M2MMAX) 520 IP6STAT_INC( 521 ip6s_m2m[m->m_pkthdr.rcvif->if_index]); 522 else 523 IP6STAT_INC(ip6s_m2m[0]); 524 } else 525 IP6STAT_INC(ip6s_m1); 526 } 527 528 /* drop the packet if IPv6 operation is disabled on the IF */ 529 if ((ND_IFINFO(m->m_pkthdr.rcvif)->flags & ND6_IFF_IFDISABLED)) 530 goto bad; 531 532 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_receive); 533 IP6STAT_INC(ip6s_total); 534 535 #ifndef PULLDOWN_TEST 536 /* 537 * L2 bridge code and some other code can return mbuf chain 538 * that does not conform to KAME requirement. too bad. 539 * XXX: fails to join if interface MTU > MCLBYTES. jumbogram? 540 */ 541 if (m && m->m_next != NULL && m->m_pkthdr.len < MCLBYTES) { 542 struct mbuf *n; 543 544 if (m->m_pkthdr.len > MHLEN) 545 n = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR); 546 else 547 n = m_gethdr(M_NOWAIT, MT_DATA); 548 if (n == NULL) { 549 m_freem(m); 550 return; /* ENOBUFS */ 551 } 552 553 m_move_pkthdr(n, m); 554 m_copydata(m, 0, n->m_pkthdr.len, mtod(n, caddr_t)); 555 n->m_len = n->m_pkthdr.len; 556 m_freem(m); 557 m = n; 558 } 559 IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), /* nothing */); 560 #endif 561 562 if (m->m_len < sizeof(struct ip6_hdr)) { 563 struct ifnet *inifp; 564 inifp = m->m_pkthdr.rcvif; 565 if ((m = m_pullup(m, sizeof(struct ip6_hdr))) == NULL) { 566 IP6STAT_INC(ip6s_toosmall); 567 in6_ifstat_inc(inifp, ifs6_in_hdrerr); 568 return; 569 } 570 } 571 572 ip6 = mtod(m, struct ip6_hdr *); 573 574 if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) { 575 IP6STAT_INC(ip6s_badvers); 576 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_hdrerr); 577 goto bad; 578 } 579 580 IP6STAT_INC(ip6s_nxthist[ip6->ip6_nxt]); 581 582 IP_PROBE(receive, NULL, NULL, ip6, m->m_pkthdr.rcvif, NULL, ip6); 583 584 /* 585 * Check against address spoofing/corruption. 586 */ 587 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_src) || 588 IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_dst)) { 589 /* 590 * XXX: "badscope" is not very suitable for a multicast source. 591 */ 592 IP6STAT_INC(ip6s_badscope); 593 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr); 594 goto bad; 595 } 596 if (IN6_IS_ADDR_MC_INTFACELOCAL(&ip6->ip6_dst) && 597 !(m->m_flags & M_LOOP)) { 598 /* 599 * In this case, the packet should come from the loopback 600 * interface. However, we cannot just check the if_flags, 601 * because ip6_mloopback() passes the "actual" interface 602 * as the outgoing/incoming interface. 603 */ 604 IP6STAT_INC(ip6s_badscope); 605 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr); 606 goto bad; 607 } 608 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) && 609 IPV6_ADDR_MC_SCOPE(&ip6->ip6_dst) == 0) { 610 /* 611 * RFC4291 2.7: 612 * Nodes must not originate a packet to a multicast address 613 * whose scop field contains the reserved value 0; if such 614 * a packet is received, it must be silently dropped. 615 */ 616 IP6STAT_INC(ip6s_badscope); 617 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr); 618 goto bad; 619 } 620 #ifdef ALTQ 621 if (altq_input != NULL && (*altq_input)(m, AF_INET6) == 0) { 622 /* packet is dropped by traffic conditioner */ 623 return; 624 } 625 #endif 626 /* 627 * The following check is not documented in specs. A malicious 628 * party may be able to use IPv4 mapped addr to confuse tcp/udp stack 629 * and bypass security checks (act as if it was from 127.0.0.1 by using 630 * IPv6 src ::ffff:127.0.0.1). Be cautious. 631 * 632 * This check chokes if we are in an SIIT cloud. As none of BSDs 633 * support IPv4-less kernel compilation, we cannot support SIIT 634 * environment at all. So, it makes more sense for us to reject any 635 * malicious packets for non-SIIT environment, than try to do a 636 * partial support for SIIT environment. 637 */ 638 if (IN6_IS_ADDR_V4MAPPED(&ip6->ip6_src) || 639 IN6_IS_ADDR_V4MAPPED(&ip6->ip6_dst)) { 640 IP6STAT_INC(ip6s_badscope); 641 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr); 642 goto bad; 643 } 644 #if 0 645 /* 646 * Reject packets with IPv4 compatible addresses (auto tunnel). 647 * 648 * The code forbids auto tunnel relay case in RFC1933 (the check is 649 * stronger than RFC1933). We may want to re-enable it if mech-xx 650 * is revised to forbid relaying case. 651 */ 652 if (IN6_IS_ADDR_V4COMPAT(&ip6->ip6_src) || 653 IN6_IS_ADDR_V4COMPAT(&ip6->ip6_dst)) { 654 IP6STAT_INC(ip6s_badscope); 655 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr); 656 goto bad; 657 } 658 #endif 659 #ifdef IPSEC 660 /* 661 * Bypass packet filtering for packets previously handled by IPsec. 662 */ 663 if (ip6_ipsec_filtertunnel(m)) 664 goto passin; 665 #endif /* IPSEC */ 666 667 /* 668 * Run through list of hooks for input packets. 669 * 670 * NB: Beware of the destination address changing 671 * (e.g. by NAT rewriting). When this happens, 672 * tell ip6_forward to do the right thing. 673 */ 674 odst = ip6->ip6_dst; 675 676 /* Jump over all PFIL processing if hooks are not active. */ 677 if (!PFIL_HOOKED(&V_inet6_pfil_hook)) 678 goto passin; 679 680 if (pfil_run_hooks(&V_inet6_pfil_hook, &m, 681 m->m_pkthdr.rcvif, PFIL_IN, NULL)) 682 return; 683 if (m == NULL) /* consumed by filter */ 684 return; 685 ip6 = mtod(m, struct ip6_hdr *); 686 srcrt = !IN6_ARE_ADDR_EQUAL(&odst, &ip6->ip6_dst); 687 688 if (m->m_flags & M_FASTFWD_OURS) { 689 m->m_flags &= ~M_FASTFWD_OURS; 690 ours = 1; 691 goto hbhcheck; 692 } 693 if ((m->m_flags & M_IP6_NEXTHOP) && 694 m_tag_find(m, PACKET_TAG_IPFORWARD, NULL) != NULL) { 695 /* 696 * Directly ship the packet on. This allows forwarding 697 * packets originally destined to us to some other directly 698 * connected host. 699 */ 700 ip6_forward(m, 1); 701 return; 702 } 703 704 passin: 705 /* 706 * Disambiguate address scope zones (if there is ambiguity). 707 * We first make sure that the original source or destination address 708 * is not in our internal form for scoped addresses. Such addresses 709 * are not necessarily invalid spec-wise, but we cannot accept them due 710 * to the usage conflict. 711 * in6_setscope() then also checks and rejects the cases where src or 712 * dst are the loopback address and the receiving interface 713 * is not loopback. 714 */ 715 if (in6_clearscope(&ip6->ip6_src) || in6_clearscope(&ip6->ip6_dst)) { 716 IP6STAT_INC(ip6s_badscope); /* XXX */ 717 goto bad; 718 } 719 if (in6_setscope(&ip6->ip6_src, m->m_pkthdr.rcvif, NULL) || 720 in6_setscope(&ip6->ip6_dst, m->m_pkthdr.rcvif, NULL)) { 721 IP6STAT_INC(ip6s_badscope); 722 goto bad; 723 } 724 /* 725 * Multicast check. Assume packet is for us to avoid 726 * prematurely taking locks. 727 */ 728 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 729 ours = 1; 730 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mcast); 731 goto hbhcheck; 732 } 733 /* 734 * Unicast check 735 * XXX: For now we keep link-local IPv6 addresses with embedded 736 * scope zone id, therefore we use zero zoneid here. 737 */ 738 ia = in6ifa_ifwithaddr(&ip6->ip6_dst, 0 /* XXX */); 739 if (ia != NULL) { 740 if (ia->ia6_flags & IN6_IFF_NOTREADY) { 741 char ip6bufs[INET6_ADDRSTRLEN]; 742 char ip6bufd[INET6_ADDRSTRLEN]; 743 /* address is not ready, so discard the packet. */ 744 nd6log((LOG_INFO, 745 "ip6_input: packet to an unready address %s->%s\n", 746 ip6_sprintf(ip6bufs, &ip6->ip6_src), 747 ip6_sprintf(ip6bufd, &ip6->ip6_dst))); 748 ifa_free(&ia->ia_ifa); 749 goto bad; 750 } 751 /* Count the packet in the ip address stats */ 752 counter_u64_add(ia->ia_ifa.ifa_ipackets, 1); 753 counter_u64_add(ia->ia_ifa.ifa_ibytes, m->m_pkthdr.len); 754 ifa_free(&ia->ia_ifa); 755 ours = 1; 756 goto hbhcheck; 757 } 758 759 /* 760 * Now there is no reason to process the packet if it's not our own 761 * and we're not a router. 762 */ 763 if (!V_ip6_forwarding) { 764 IP6STAT_INC(ip6s_cantforward); 765 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard); 766 goto bad; 767 } 768 769 hbhcheck: 770 /* 771 * Process Hop-by-Hop options header if it's contained. 772 * m may be modified in ip6_hopopts_input(). 773 * If a JumboPayload option is included, plen will also be modified. 774 */ 775 plen = (u_int32_t)ntohs(ip6->ip6_plen); 776 if (ip6->ip6_nxt == IPPROTO_HOPOPTS) { 777 if (ip6_input_hbh(m, &plen, &rtalert, &off, &nxt, &ours) != 0) 778 return; 779 } else 780 nxt = ip6->ip6_nxt; 781 782 /* 783 * Use mbuf flags to propagate Router Alert option to 784 * ICMPv6 layer, as hop-by-hop options have been stripped. 785 */ 786 if (rtalert != ~0) 787 m->m_flags |= M_RTALERT_MLD; 788 789 /* 790 * Check that the amount of data in the buffers 791 * is as at least much as the IPv6 header would have us expect. 792 * Trim mbufs if longer than we expect. 793 * Drop packet if shorter than we expect. 794 */ 795 if (m->m_pkthdr.len - sizeof(struct ip6_hdr) < plen) { 796 IP6STAT_INC(ip6s_tooshort); 797 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_truncated); 798 goto bad; 799 } 800 if (m->m_pkthdr.len > sizeof(struct ip6_hdr) + plen) { 801 if (m->m_len == m->m_pkthdr.len) { 802 m->m_len = sizeof(struct ip6_hdr) + plen; 803 m->m_pkthdr.len = sizeof(struct ip6_hdr) + plen; 804 } else 805 m_adj(m, sizeof(struct ip6_hdr) + plen - m->m_pkthdr.len); 806 } 807 808 /* 809 * Forward if desirable. 810 */ 811 if (V_ip6_mrouter && 812 IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 813 /* 814 * If we are acting as a multicast router, all 815 * incoming multicast packets are passed to the 816 * kernel-level multicast forwarding function. 817 * The packet is returned (relatively) intact; if 818 * ip6_mforward() returns a non-zero value, the packet 819 * must be discarded, else it may be accepted below. 820 * 821 * XXX TODO: Check hlim and multicast scope here to avoid 822 * unnecessarily calling into ip6_mforward(). 823 */ 824 if (ip6_mforward && 825 ip6_mforward(ip6, m->m_pkthdr.rcvif, m)) { 826 IP6STAT_INC(ip6s_cantforward); 827 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard); 828 goto bad; 829 } 830 } else if (!ours) { 831 ip6_forward(m, srcrt); 832 return; 833 } 834 835 ip6 = mtod(m, struct ip6_hdr *); 836 837 /* 838 * Malicious party may be able to use IPv4 mapped addr to confuse 839 * tcp/udp stack and bypass security checks (act as if it was from 840 * 127.0.0.1 by using IPv6 src ::ffff:127.0.0.1). Be cautious. 841 * 842 * For SIIT end node behavior, you may want to disable the check. 843 * However, you will become vulnerable to attacks using IPv4 mapped 844 * source. 845 */ 846 if (IN6_IS_ADDR_V4MAPPED(&ip6->ip6_src) || 847 IN6_IS_ADDR_V4MAPPED(&ip6->ip6_dst)) { 848 IP6STAT_INC(ip6s_badscope); 849 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr); 850 goto bad; 851 } 852 853 /* 854 * Tell launch routine the next header 855 */ 856 IP6STAT_INC(ip6s_delivered); 857 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_deliver); 858 nest = 0; 859 860 while (nxt != IPPROTO_DONE) { 861 if (V_ip6_hdrnestlimit && (++nest > V_ip6_hdrnestlimit)) { 862 IP6STAT_INC(ip6s_toomanyhdr); 863 goto bad; 864 } 865 866 /* 867 * protection against faulty packet - there should be 868 * more sanity checks in header chain processing. 869 */ 870 if (m->m_pkthdr.len < off) { 871 IP6STAT_INC(ip6s_tooshort); 872 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_truncated); 873 goto bad; 874 } 875 876 #ifdef IPSEC 877 /* 878 * enforce IPsec policy checking if we are seeing last header. 879 * note that we do not visit this with protocols with pcb layer 880 * code - like udp/tcp/raw ip. 881 */ 882 if (ip6_ipsec_input(m, nxt)) 883 goto bad; 884 #endif /* IPSEC */ 885 886 nxt = (*inet6sw[ip6_protox[nxt]].pr_input)(&m, &off, nxt); 887 } 888 return; 889 bad: 890 m_freem(m); 891 } 892 893 /* 894 * Hop-by-Hop options header processing. If a valid jumbo payload option is 895 * included, the real payload length will be stored in plenp. 896 * 897 * rtalertp - XXX: should be stored more smart way 898 */ 899 static int 900 ip6_hopopts_input(u_int32_t *plenp, u_int32_t *rtalertp, 901 struct mbuf **mp, int *offp) 902 { 903 struct mbuf *m = *mp; 904 int off = *offp, hbhlen; 905 struct ip6_hbh *hbh; 906 907 /* validation of the length of the header */ 908 #ifndef PULLDOWN_TEST 909 IP6_EXTHDR_CHECK(m, off, sizeof(*hbh), -1); 910 hbh = (struct ip6_hbh *)(mtod(m, caddr_t) + off); 911 hbhlen = (hbh->ip6h_len + 1) << 3; 912 913 IP6_EXTHDR_CHECK(m, off, hbhlen, -1); 914 hbh = (struct ip6_hbh *)(mtod(m, caddr_t) + off); 915 #else 916 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, 917 sizeof(struct ip6_hdr), sizeof(struct ip6_hbh)); 918 if (hbh == NULL) { 919 IP6STAT_INC(ip6s_tooshort); 920 return -1; 921 } 922 hbhlen = (hbh->ip6h_len + 1) << 3; 923 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, sizeof(struct ip6_hdr), 924 hbhlen); 925 if (hbh == NULL) { 926 IP6STAT_INC(ip6s_tooshort); 927 return -1; 928 } 929 #endif 930 off += hbhlen; 931 hbhlen -= sizeof(struct ip6_hbh); 932 if (ip6_process_hopopts(m, (u_int8_t *)hbh + sizeof(struct ip6_hbh), 933 hbhlen, rtalertp, plenp) < 0) 934 return (-1); 935 936 *offp = off; 937 *mp = m; 938 return (0); 939 } 940 941 /* 942 * Search header for all Hop-by-hop options and process each option. 943 * This function is separate from ip6_hopopts_input() in order to 944 * handle a case where the sending node itself process its hop-by-hop 945 * options header. In such a case, the function is called from ip6_output(). 946 * 947 * The function assumes that hbh header is located right after the IPv6 header 948 * (RFC2460 p7), opthead is pointer into data content in m, and opthead to 949 * opthead + hbhlen is located in contiguous memory region. 950 */ 951 int 952 ip6_process_hopopts(struct mbuf *m, u_int8_t *opthead, int hbhlen, 953 u_int32_t *rtalertp, u_int32_t *plenp) 954 { 955 struct ip6_hdr *ip6; 956 int optlen = 0; 957 u_int8_t *opt = opthead; 958 u_int16_t rtalert_val; 959 u_int32_t jumboplen; 960 const int erroff = sizeof(struct ip6_hdr) + sizeof(struct ip6_hbh); 961 962 for (; hbhlen > 0; hbhlen -= optlen, opt += optlen) { 963 switch (*opt) { 964 case IP6OPT_PAD1: 965 optlen = 1; 966 break; 967 case IP6OPT_PADN: 968 if (hbhlen < IP6OPT_MINLEN) { 969 IP6STAT_INC(ip6s_toosmall); 970 goto bad; 971 } 972 optlen = *(opt + 1) + 2; 973 break; 974 case IP6OPT_ROUTER_ALERT: 975 /* XXX may need check for alignment */ 976 if (hbhlen < IP6OPT_RTALERT_LEN) { 977 IP6STAT_INC(ip6s_toosmall); 978 goto bad; 979 } 980 if (*(opt + 1) != IP6OPT_RTALERT_LEN - 2) { 981 /* XXX stat */ 982 icmp6_error(m, ICMP6_PARAM_PROB, 983 ICMP6_PARAMPROB_HEADER, 984 erroff + opt + 1 - opthead); 985 return (-1); 986 } 987 optlen = IP6OPT_RTALERT_LEN; 988 bcopy((caddr_t)(opt + 2), (caddr_t)&rtalert_val, 2); 989 *rtalertp = ntohs(rtalert_val); 990 break; 991 case IP6OPT_JUMBO: 992 /* XXX may need check for alignment */ 993 if (hbhlen < IP6OPT_JUMBO_LEN) { 994 IP6STAT_INC(ip6s_toosmall); 995 goto bad; 996 } 997 if (*(opt + 1) != IP6OPT_JUMBO_LEN - 2) { 998 /* XXX stat */ 999 icmp6_error(m, ICMP6_PARAM_PROB, 1000 ICMP6_PARAMPROB_HEADER, 1001 erroff + opt + 1 - opthead); 1002 return (-1); 1003 } 1004 optlen = IP6OPT_JUMBO_LEN; 1005 1006 /* 1007 * IPv6 packets that have non 0 payload length 1008 * must not contain a jumbo payload option. 1009 */ 1010 ip6 = mtod(m, struct ip6_hdr *); 1011 if (ip6->ip6_plen) { 1012 IP6STAT_INC(ip6s_badoptions); 1013 icmp6_error(m, ICMP6_PARAM_PROB, 1014 ICMP6_PARAMPROB_HEADER, 1015 erroff + opt - opthead); 1016 return (-1); 1017 } 1018 1019 /* 1020 * We may see jumbolen in unaligned location, so 1021 * we'd need to perform bcopy(). 1022 */ 1023 bcopy(opt + 2, &jumboplen, sizeof(jumboplen)); 1024 jumboplen = (u_int32_t)htonl(jumboplen); 1025 1026 #if 1 1027 /* 1028 * if there are multiple jumbo payload options, 1029 * *plenp will be non-zero and the packet will be 1030 * rejected. 1031 * the behavior may need some debate in ipngwg - 1032 * multiple options does not make sense, however, 1033 * there's no explicit mention in specification. 1034 */ 1035 if (*plenp != 0) { 1036 IP6STAT_INC(ip6s_badoptions); 1037 icmp6_error(m, ICMP6_PARAM_PROB, 1038 ICMP6_PARAMPROB_HEADER, 1039 erroff + opt + 2 - opthead); 1040 return (-1); 1041 } 1042 #endif 1043 1044 /* 1045 * jumbo payload length must be larger than 65535. 1046 */ 1047 if (jumboplen <= IPV6_MAXPACKET) { 1048 IP6STAT_INC(ip6s_badoptions); 1049 icmp6_error(m, ICMP6_PARAM_PROB, 1050 ICMP6_PARAMPROB_HEADER, 1051 erroff + opt + 2 - opthead); 1052 return (-1); 1053 } 1054 *plenp = jumboplen; 1055 1056 break; 1057 default: /* unknown option */ 1058 if (hbhlen < IP6OPT_MINLEN) { 1059 IP6STAT_INC(ip6s_toosmall); 1060 goto bad; 1061 } 1062 optlen = ip6_unknown_opt(opt, m, 1063 erroff + opt - opthead); 1064 if (optlen == -1) 1065 return (-1); 1066 optlen += 2; 1067 break; 1068 } 1069 } 1070 1071 return (0); 1072 1073 bad: 1074 m_freem(m); 1075 return (-1); 1076 } 1077 1078 /* 1079 * Unknown option processing. 1080 * The third argument `off' is the offset from the IPv6 header to the option, 1081 * which is necessary if the IPv6 header the and option header and IPv6 header 1082 * is not contiguous in order to return an ICMPv6 error. 1083 */ 1084 int 1085 ip6_unknown_opt(u_int8_t *optp, struct mbuf *m, int off) 1086 { 1087 struct ip6_hdr *ip6; 1088 1089 switch (IP6OPT_TYPE(*optp)) { 1090 case IP6OPT_TYPE_SKIP: /* ignore the option */ 1091 return ((int)*(optp + 1)); 1092 case IP6OPT_TYPE_DISCARD: /* silently discard */ 1093 m_freem(m); 1094 return (-1); 1095 case IP6OPT_TYPE_FORCEICMP: /* send ICMP even if multicasted */ 1096 IP6STAT_INC(ip6s_badoptions); 1097 icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_OPTION, off); 1098 return (-1); 1099 case IP6OPT_TYPE_ICMP: /* send ICMP if not multicasted */ 1100 IP6STAT_INC(ip6s_badoptions); 1101 ip6 = mtod(m, struct ip6_hdr *); 1102 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) || 1103 (m->m_flags & (M_BCAST|M_MCAST))) 1104 m_freem(m); 1105 else 1106 icmp6_error(m, ICMP6_PARAM_PROB, 1107 ICMP6_PARAMPROB_OPTION, off); 1108 return (-1); 1109 } 1110 1111 m_freem(m); /* XXX: NOTREACHED */ 1112 return (-1); 1113 } 1114 1115 /* 1116 * Create the "control" list for this pcb. 1117 * These functions will not modify mbuf chain at all. 1118 * 1119 * With KAME mbuf chain restriction: 1120 * The routine will be called from upper layer handlers like tcp6_input(). 1121 * Thus the routine assumes that the caller (tcp6_input) have already 1122 * called IP6_EXTHDR_CHECK() and all the extension headers are located in the 1123 * very first mbuf on the mbuf chain. 1124 * 1125 * ip6_savecontrol_v4 will handle those options that are possible to be 1126 * set on a v4-mapped socket. 1127 * ip6_savecontrol will directly call ip6_savecontrol_v4 to handle those 1128 * options and handle the v6-only ones itself. 1129 */ 1130 struct mbuf ** 1131 ip6_savecontrol_v4(struct inpcb *inp, struct mbuf *m, struct mbuf **mp, 1132 int *v4only) 1133 { 1134 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1135 1136 #ifdef SO_TIMESTAMP 1137 if ((inp->inp_socket->so_options & SO_TIMESTAMP) != 0) { 1138 struct timeval tv; 1139 1140 microtime(&tv); 1141 *mp = sbcreatecontrol((caddr_t) &tv, sizeof(tv), 1142 SCM_TIMESTAMP, SOL_SOCKET); 1143 if (*mp) 1144 mp = &(*mp)->m_next; 1145 } 1146 #endif 1147 1148 #define IS2292(inp, x, y) (((inp)->inp_flags & IN6P_RFC2292) ? (x) : (y)) 1149 /* RFC 2292 sec. 5 */ 1150 if ((inp->inp_flags & IN6P_PKTINFO) != 0) { 1151 struct in6_pktinfo pi6; 1152 1153 if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) { 1154 #ifdef INET 1155 struct ip *ip; 1156 1157 ip = mtod(m, struct ip *); 1158 pi6.ipi6_addr.s6_addr32[0] = 0; 1159 pi6.ipi6_addr.s6_addr32[1] = 0; 1160 pi6.ipi6_addr.s6_addr32[2] = IPV6_ADDR_INT32_SMP; 1161 pi6.ipi6_addr.s6_addr32[3] = ip->ip_dst.s_addr; 1162 #else 1163 /* We won't hit this code */ 1164 bzero(&pi6.ipi6_addr, sizeof(struct in6_addr)); 1165 #endif 1166 } else { 1167 bcopy(&ip6->ip6_dst, &pi6.ipi6_addr, sizeof(struct in6_addr)); 1168 in6_clearscope(&pi6.ipi6_addr); /* XXX */ 1169 } 1170 pi6.ipi6_ifindex = 1171 (m && m->m_pkthdr.rcvif) ? m->m_pkthdr.rcvif->if_index : 0; 1172 1173 *mp = sbcreatecontrol((caddr_t) &pi6, 1174 sizeof(struct in6_pktinfo), 1175 IS2292(inp, IPV6_2292PKTINFO, IPV6_PKTINFO), IPPROTO_IPV6); 1176 if (*mp) 1177 mp = &(*mp)->m_next; 1178 } 1179 1180 if ((inp->inp_flags & IN6P_HOPLIMIT) != 0) { 1181 int hlim; 1182 1183 if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) { 1184 #ifdef INET 1185 struct ip *ip; 1186 1187 ip = mtod(m, struct ip *); 1188 hlim = ip->ip_ttl; 1189 #else 1190 /* We won't hit this code */ 1191 hlim = 0; 1192 #endif 1193 } else { 1194 hlim = ip6->ip6_hlim & 0xff; 1195 } 1196 *mp = sbcreatecontrol((caddr_t) &hlim, sizeof(int), 1197 IS2292(inp, IPV6_2292HOPLIMIT, IPV6_HOPLIMIT), 1198 IPPROTO_IPV6); 1199 if (*mp) 1200 mp = &(*mp)->m_next; 1201 } 1202 1203 if ((inp->inp_flags & IN6P_TCLASS) != 0) { 1204 int tclass; 1205 1206 if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) { 1207 #ifdef INET 1208 struct ip *ip; 1209 1210 ip = mtod(m, struct ip *); 1211 tclass = ip->ip_tos; 1212 #else 1213 /* We won't hit this code */ 1214 tclass = 0; 1215 #endif 1216 } else { 1217 u_int32_t flowinfo; 1218 1219 flowinfo = (u_int32_t)ntohl(ip6->ip6_flow & IPV6_FLOWINFO_MASK); 1220 flowinfo >>= 20; 1221 tclass = flowinfo & 0xff; 1222 } 1223 *mp = sbcreatecontrol((caddr_t) &tclass, sizeof(int), 1224 IPV6_TCLASS, IPPROTO_IPV6); 1225 if (*mp) 1226 mp = &(*mp)->m_next; 1227 } 1228 1229 if (v4only != NULL) { 1230 if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) { 1231 *v4only = 1; 1232 } else { 1233 *v4only = 0; 1234 } 1235 } 1236 1237 return (mp); 1238 } 1239 1240 void 1241 ip6_savecontrol(struct inpcb *in6p, struct mbuf *m, struct mbuf **mp) 1242 { 1243 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1244 int v4only = 0; 1245 1246 mp = ip6_savecontrol_v4(in6p, m, mp, &v4only); 1247 if (v4only) 1248 return; 1249 1250 /* 1251 * IPV6_HOPOPTS socket option. Recall that we required super-user 1252 * privilege for the option (see ip6_ctloutput), but it might be too 1253 * strict, since there might be some hop-by-hop options which can be 1254 * returned to normal user. 1255 * See also RFC 2292 section 6 (or RFC 3542 section 8). 1256 */ 1257 if ((in6p->inp_flags & IN6P_HOPOPTS) != 0) { 1258 /* 1259 * Check if a hop-by-hop options header is contatined in the 1260 * received packet, and if so, store the options as ancillary 1261 * data. Note that a hop-by-hop options header must be 1262 * just after the IPv6 header, which is assured through the 1263 * IPv6 input processing. 1264 */ 1265 if (ip6->ip6_nxt == IPPROTO_HOPOPTS) { 1266 struct ip6_hbh *hbh; 1267 int hbhlen = 0; 1268 #ifdef PULLDOWN_TEST 1269 struct mbuf *ext; 1270 #endif 1271 1272 #ifndef PULLDOWN_TEST 1273 hbh = (struct ip6_hbh *)(ip6 + 1); 1274 hbhlen = (hbh->ip6h_len + 1) << 3; 1275 #else 1276 ext = ip6_pullexthdr(m, sizeof(struct ip6_hdr), 1277 ip6->ip6_nxt); 1278 if (ext == NULL) { 1279 IP6STAT_INC(ip6s_tooshort); 1280 return; 1281 } 1282 hbh = mtod(ext, struct ip6_hbh *); 1283 hbhlen = (hbh->ip6h_len + 1) << 3; 1284 if (hbhlen != ext->m_len) { 1285 m_freem(ext); 1286 IP6STAT_INC(ip6s_tooshort); 1287 return; 1288 } 1289 #endif 1290 1291 /* 1292 * XXX: We copy the whole header even if a 1293 * jumbo payload option is included, the option which 1294 * is to be removed before returning according to 1295 * RFC2292. 1296 * Note: this constraint is removed in RFC3542 1297 */ 1298 *mp = sbcreatecontrol((caddr_t)hbh, hbhlen, 1299 IS2292(in6p, IPV6_2292HOPOPTS, IPV6_HOPOPTS), 1300 IPPROTO_IPV6); 1301 if (*mp) 1302 mp = &(*mp)->m_next; 1303 #ifdef PULLDOWN_TEST 1304 m_freem(ext); 1305 #endif 1306 } 1307 } 1308 1309 if ((in6p->inp_flags & (IN6P_RTHDR | IN6P_DSTOPTS)) != 0) { 1310 int nxt = ip6->ip6_nxt, off = sizeof(struct ip6_hdr); 1311 1312 /* 1313 * Search for destination options headers or routing 1314 * header(s) through the header chain, and stores each 1315 * header as ancillary data. 1316 * Note that the order of the headers remains in 1317 * the chain of ancillary data. 1318 */ 1319 while (1) { /* is explicit loop prevention necessary? */ 1320 struct ip6_ext *ip6e = NULL; 1321 int elen; 1322 #ifdef PULLDOWN_TEST 1323 struct mbuf *ext = NULL; 1324 #endif 1325 1326 /* 1327 * if it is not an extension header, don't try to 1328 * pull it from the chain. 1329 */ 1330 switch (nxt) { 1331 case IPPROTO_DSTOPTS: 1332 case IPPROTO_ROUTING: 1333 case IPPROTO_HOPOPTS: 1334 case IPPROTO_AH: /* is it possible? */ 1335 break; 1336 default: 1337 goto loopend; 1338 } 1339 1340 #ifndef PULLDOWN_TEST 1341 if (off + sizeof(*ip6e) > m->m_len) 1342 goto loopend; 1343 ip6e = (struct ip6_ext *)(mtod(m, caddr_t) + off); 1344 if (nxt == IPPROTO_AH) 1345 elen = (ip6e->ip6e_len + 2) << 2; 1346 else 1347 elen = (ip6e->ip6e_len + 1) << 3; 1348 if (off + elen > m->m_len) 1349 goto loopend; 1350 #else 1351 ext = ip6_pullexthdr(m, off, nxt); 1352 if (ext == NULL) { 1353 IP6STAT_INC(ip6s_tooshort); 1354 return; 1355 } 1356 ip6e = mtod(ext, struct ip6_ext *); 1357 if (nxt == IPPROTO_AH) 1358 elen = (ip6e->ip6e_len + 2) << 2; 1359 else 1360 elen = (ip6e->ip6e_len + 1) << 3; 1361 if (elen != ext->m_len) { 1362 m_freem(ext); 1363 IP6STAT_INC(ip6s_tooshort); 1364 return; 1365 } 1366 #endif 1367 1368 switch (nxt) { 1369 case IPPROTO_DSTOPTS: 1370 if (!(in6p->inp_flags & IN6P_DSTOPTS)) 1371 break; 1372 1373 *mp = sbcreatecontrol((caddr_t)ip6e, elen, 1374 IS2292(in6p, 1375 IPV6_2292DSTOPTS, IPV6_DSTOPTS), 1376 IPPROTO_IPV6); 1377 if (*mp) 1378 mp = &(*mp)->m_next; 1379 break; 1380 case IPPROTO_ROUTING: 1381 if (!(in6p->inp_flags & IN6P_RTHDR)) 1382 break; 1383 1384 *mp = sbcreatecontrol((caddr_t)ip6e, elen, 1385 IS2292(in6p, IPV6_2292RTHDR, IPV6_RTHDR), 1386 IPPROTO_IPV6); 1387 if (*mp) 1388 mp = &(*mp)->m_next; 1389 break; 1390 case IPPROTO_HOPOPTS: 1391 case IPPROTO_AH: /* is it possible? */ 1392 break; 1393 1394 default: 1395 /* 1396 * other cases have been filtered in the above. 1397 * none will visit this case. here we supply 1398 * the code just in case (nxt overwritten or 1399 * other cases). 1400 */ 1401 #ifdef PULLDOWN_TEST 1402 m_freem(ext); 1403 #endif 1404 goto loopend; 1405 1406 } 1407 1408 /* proceed with the next header. */ 1409 off += elen; 1410 nxt = ip6e->ip6e_nxt; 1411 ip6e = NULL; 1412 #ifdef PULLDOWN_TEST 1413 m_freem(ext); 1414 ext = NULL; 1415 #endif 1416 } 1417 loopend: 1418 ; 1419 } 1420 1421 if (in6p->inp_flags2 & INP_RECVFLOWID) { 1422 uint32_t flowid, flow_type; 1423 1424 flowid = m->m_pkthdr.flowid; 1425 flow_type = M_HASHTYPE_GET(m); 1426 1427 /* 1428 * XXX should handle the failure of one or the 1429 * other - don't populate both? 1430 */ 1431 *mp = sbcreatecontrol((caddr_t) &flowid, 1432 sizeof(uint32_t), IPV6_FLOWID, IPPROTO_IPV6); 1433 if (*mp) 1434 mp = &(*mp)->m_next; 1435 *mp = sbcreatecontrol((caddr_t) &flow_type, 1436 sizeof(uint32_t), IPV6_FLOWTYPE, IPPROTO_IPV6); 1437 if (*mp) 1438 mp = &(*mp)->m_next; 1439 } 1440 1441 #ifdef RSS 1442 if (in6p->inp_flags2 & INP_RECVRSSBUCKETID) { 1443 uint32_t flowid, flow_type; 1444 uint32_t rss_bucketid; 1445 1446 flowid = m->m_pkthdr.flowid; 1447 flow_type = M_HASHTYPE_GET(m); 1448 1449 if (rss_hash2bucket(flowid, flow_type, &rss_bucketid) == 0) { 1450 *mp = sbcreatecontrol((caddr_t) &rss_bucketid, 1451 sizeof(uint32_t), IPV6_RSSBUCKETID, IPPROTO_IPV6); 1452 if (*mp) 1453 mp = &(*mp)->m_next; 1454 } 1455 } 1456 #endif 1457 1458 } 1459 #undef IS2292 1460 1461 void 1462 ip6_notify_pmtu(struct inpcb *inp, struct sockaddr_in6 *dst, u_int32_t mtu) 1463 { 1464 struct socket *so; 1465 struct mbuf *m_mtu; 1466 struct ip6_mtuinfo mtuctl; 1467 1468 KASSERT(inp != NULL, ("%s: inp == NULL", __func__)); 1469 /* 1470 * Notify the error by sending IPV6_PATHMTU ancillary data if 1471 * application wanted to know the MTU value. 1472 * NOTE: we notify disconnected sockets, because some udp 1473 * applications keep sending sockets disconnected. 1474 * NOTE: our implementation doesn't notify connected sockets that has 1475 * foreign address that is different than given destination addresses 1476 * (this is permitted by RFC 3542). 1477 */ 1478 if ((inp->inp_flags & IN6P_MTU) == 0 || ( 1479 !IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr) && 1480 !IN6_ARE_ADDR_EQUAL(&inp->in6p_faddr, &dst->sin6_addr))) 1481 return; 1482 1483 mtuctl.ip6m_mtu = mtu; 1484 mtuctl.ip6m_addr = *dst; 1485 if (sa6_recoverscope(&mtuctl.ip6m_addr)) 1486 return; 1487 1488 if ((m_mtu = sbcreatecontrol((caddr_t)&mtuctl, sizeof(mtuctl), 1489 IPV6_PATHMTU, IPPROTO_IPV6)) == NULL) 1490 return; 1491 1492 so = inp->inp_socket; 1493 if (sbappendaddr(&so->so_rcv, (struct sockaddr *)dst, NULL, m_mtu) 1494 == 0) { 1495 m_freem(m_mtu); 1496 /* XXX: should count statistics */ 1497 } else 1498 sorwakeup(so); 1499 } 1500 1501 #ifdef PULLDOWN_TEST 1502 /* 1503 * pull single extension header from mbuf chain. returns single mbuf that 1504 * contains the result, or NULL on error. 1505 */ 1506 static struct mbuf * 1507 ip6_pullexthdr(struct mbuf *m, size_t off, int nxt) 1508 { 1509 struct ip6_ext ip6e; 1510 size_t elen; 1511 struct mbuf *n; 1512 1513 #ifdef DIAGNOSTIC 1514 switch (nxt) { 1515 case IPPROTO_DSTOPTS: 1516 case IPPROTO_ROUTING: 1517 case IPPROTO_HOPOPTS: 1518 case IPPROTO_AH: /* is it possible? */ 1519 break; 1520 default: 1521 printf("ip6_pullexthdr: invalid nxt=%d\n", nxt); 1522 } 1523 #endif 1524 1525 m_copydata(m, off, sizeof(ip6e), (caddr_t)&ip6e); 1526 if (nxt == IPPROTO_AH) 1527 elen = (ip6e.ip6e_len + 2) << 2; 1528 else 1529 elen = (ip6e.ip6e_len + 1) << 3; 1530 1531 if (elen > MLEN) 1532 n = m_getcl(M_NOWAIT, MT_DATA, 0); 1533 else 1534 n = m_get(M_NOWAIT, MT_DATA); 1535 if (n == NULL) 1536 return NULL; 1537 1538 m_copydata(m, off, elen, mtod(n, caddr_t)); 1539 n->m_len = elen; 1540 return n; 1541 } 1542 #endif 1543 1544 /* 1545 * Get pointer to the previous header followed by the header 1546 * currently processed. 1547 * XXX: This function supposes that 1548 * M includes all headers, 1549 * the next header field and the header length field of each header 1550 * are valid, and 1551 * the sum of each header length equals to OFF. 1552 * Because of these assumptions, this function must be called very 1553 * carefully. Moreover, it will not be used in the near future when 1554 * we develop `neater' mechanism to process extension headers. 1555 */ 1556 char * 1557 ip6_get_prevhdr(const struct mbuf *m, int off) 1558 { 1559 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1560 1561 if (off == sizeof(struct ip6_hdr)) 1562 return (&ip6->ip6_nxt); 1563 else { 1564 int len, nxt; 1565 struct ip6_ext *ip6e = NULL; 1566 1567 nxt = ip6->ip6_nxt; 1568 len = sizeof(struct ip6_hdr); 1569 while (len < off) { 1570 ip6e = (struct ip6_ext *)(mtod(m, caddr_t) + len); 1571 1572 switch (nxt) { 1573 case IPPROTO_FRAGMENT: 1574 len += sizeof(struct ip6_frag); 1575 break; 1576 case IPPROTO_AH: 1577 len += (ip6e->ip6e_len + 2) << 2; 1578 break; 1579 default: 1580 len += (ip6e->ip6e_len + 1) << 3; 1581 break; 1582 } 1583 nxt = ip6e->ip6e_nxt; 1584 } 1585 if (ip6e) 1586 return (&ip6e->ip6e_nxt); 1587 else 1588 return NULL; 1589 } 1590 } 1591 1592 /* 1593 * get next header offset. m will be retained. 1594 */ 1595 int 1596 ip6_nexthdr(const struct mbuf *m, int off, int proto, int *nxtp) 1597 { 1598 struct ip6_hdr ip6; 1599 struct ip6_ext ip6e; 1600 struct ip6_frag fh; 1601 1602 /* just in case */ 1603 if (m == NULL) 1604 panic("ip6_nexthdr: m == NULL"); 1605 if ((m->m_flags & M_PKTHDR) == 0 || m->m_pkthdr.len < off) 1606 return -1; 1607 1608 switch (proto) { 1609 case IPPROTO_IPV6: 1610 if (m->m_pkthdr.len < off + sizeof(ip6)) 1611 return -1; 1612 m_copydata(m, off, sizeof(ip6), (caddr_t)&ip6); 1613 if (nxtp) 1614 *nxtp = ip6.ip6_nxt; 1615 off += sizeof(ip6); 1616 return off; 1617 1618 case IPPROTO_FRAGMENT: 1619 /* 1620 * terminate parsing if it is not the first fragment, 1621 * it does not make sense to parse through it. 1622 */ 1623 if (m->m_pkthdr.len < off + sizeof(fh)) 1624 return -1; 1625 m_copydata(m, off, sizeof(fh), (caddr_t)&fh); 1626 /* IP6F_OFF_MASK = 0xfff8(BigEndian), 0xf8ff(LittleEndian) */ 1627 if (fh.ip6f_offlg & IP6F_OFF_MASK) 1628 return -1; 1629 if (nxtp) 1630 *nxtp = fh.ip6f_nxt; 1631 off += sizeof(struct ip6_frag); 1632 return off; 1633 1634 case IPPROTO_AH: 1635 if (m->m_pkthdr.len < off + sizeof(ip6e)) 1636 return -1; 1637 m_copydata(m, off, sizeof(ip6e), (caddr_t)&ip6e); 1638 if (nxtp) 1639 *nxtp = ip6e.ip6e_nxt; 1640 off += (ip6e.ip6e_len + 2) << 2; 1641 return off; 1642 1643 case IPPROTO_HOPOPTS: 1644 case IPPROTO_ROUTING: 1645 case IPPROTO_DSTOPTS: 1646 if (m->m_pkthdr.len < off + sizeof(ip6e)) 1647 return -1; 1648 m_copydata(m, off, sizeof(ip6e), (caddr_t)&ip6e); 1649 if (nxtp) 1650 *nxtp = ip6e.ip6e_nxt; 1651 off += (ip6e.ip6e_len + 1) << 3; 1652 return off; 1653 1654 case IPPROTO_NONE: 1655 case IPPROTO_ESP: 1656 case IPPROTO_IPCOMP: 1657 /* give up */ 1658 return -1; 1659 1660 default: 1661 return -1; 1662 } 1663 1664 /* NOTREACHED */ 1665 } 1666 1667 /* 1668 * get offset for the last header in the chain. m will be kept untainted. 1669 */ 1670 int 1671 ip6_lasthdr(const struct mbuf *m, int off, int proto, int *nxtp) 1672 { 1673 int newoff; 1674 int nxt; 1675 1676 if (!nxtp) { 1677 nxt = -1; 1678 nxtp = &nxt; 1679 } 1680 while (1) { 1681 newoff = ip6_nexthdr(m, off, proto, nxtp); 1682 if (newoff < 0) 1683 return off; 1684 else if (newoff < off) 1685 return -1; /* invalid */ 1686 else if (newoff == off) 1687 return newoff; 1688 1689 off = newoff; 1690 proto = *nxtp; 1691 } 1692 } 1693 1694 /* 1695 * System control for IP6 1696 */ 1697 1698 u_char inet6ctlerrmap[PRC_NCMDS] = { 1699 0, 0, 0, 0, 1700 0, EMSGSIZE, EHOSTDOWN, EHOSTUNREACH, 1701 EHOSTUNREACH, EHOSTUNREACH, ECONNREFUSED, ECONNREFUSED, 1702 EMSGSIZE, EHOSTUNREACH, 0, 0, 1703 0, 0, 0, 0, 1704 ENOPROTOOPT 1705 }; 1706