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_DECLARE(struct callout, in6_tmpaddrtimer_ch); 160 #define V_in6_tmpaddrtimer_ch VNET(in6_tmpaddrtimer_ch) 161 162 VNET_DEFINE(struct pfil_head, inet6_pfil_hook); 163 164 VNET_PCPUSTAT_DEFINE(struct ip6stat, ip6stat); 165 VNET_PCPUSTAT_SYSINIT(ip6stat); 166 #ifdef VIMAGE 167 VNET_PCPUSTAT_SYSUNINIT(ip6stat); 168 #endif /* VIMAGE */ 169 170 struct rmlock in6_ifaddr_lock; 171 RM_SYSINIT(in6_ifaddr_lock, &in6_ifaddr_lock, "in6_ifaddr_lock"); 172 173 static void ip6_init2(void *); 174 static int ip6_hopopts_input(u_int32_t *, u_int32_t *, struct mbuf **, int *); 175 #ifdef PULLDOWN_TEST 176 static struct mbuf *ip6_pullexthdr(struct mbuf *, size_t, int); 177 #endif 178 179 /* 180 * IP6 initialization: fill in IP6 protocol switch table. 181 * All protocols not implemented in kernel go to raw IP6 protocol handler. 182 */ 183 void 184 ip6_init(void) 185 { 186 struct protosw *pr; 187 int i; 188 189 TUNABLE_INT_FETCH("net.inet6.ip6.auto_linklocal", 190 &V_ip6_auto_linklocal); 191 TUNABLE_INT_FETCH("net.inet6.ip6.accept_rtadv", &V_ip6_accept_rtadv); 192 TUNABLE_INT_FETCH("net.inet6.ip6.no_radr", &V_ip6_no_radr); 193 194 TAILQ_INIT(&V_in6_ifaddrhead); 195 V_in6_ifaddrhashtbl = hashinit(IN6ADDR_NHASH, M_IFADDR, 196 &V_in6_ifaddrhmask); 197 198 /* Initialize packet filter hooks. */ 199 V_inet6_pfil_hook.ph_type = PFIL_TYPE_AF; 200 V_inet6_pfil_hook.ph_af = AF_INET6; 201 if ((i = pfil_head_register(&V_inet6_pfil_hook)) != 0) 202 printf("%s: WARNING: unable to register pfil hook, " 203 "error %d\n", __func__, i); 204 205 if (hhook_head_register(HHOOK_TYPE_IPSEC_IN, AF_INET6, 206 &V_ipsec_hhh_in[HHOOK_IPSEC_INET6], 207 HHOOK_WAITOK | HHOOK_HEADISINVNET) != 0) 208 printf("%s: WARNING: unable to register input helper hook\n", 209 __func__); 210 if (hhook_head_register(HHOOK_TYPE_IPSEC_OUT, AF_INET6, 211 &V_ipsec_hhh_out[HHOOK_IPSEC_INET6], 212 HHOOK_WAITOK | HHOOK_HEADISINVNET) != 0) 213 printf("%s: WARNING: unable to register output helper hook\n", 214 __func__); 215 216 scope6_init(); 217 addrsel_policy_init(); 218 nd6_init(); 219 frag6_init(); 220 221 V_ip6_desync_factor = arc4random() % MAX_TEMP_DESYNC_FACTOR; 222 223 /* Skip global initialization stuff for non-default instances. */ 224 if (!IS_DEFAULT_VNET(curvnet)) 225 return; 226 227 pr = pffindproto(PF_INET6, IPPROTO_RAW, SOCK_RAW); 228 if (pr == NULL) 229 panic("ip6_init"); 230 231 /* Initialize the entire ip6_protox[] array to IPPROTO_RAW. */ 232 for (i = 0; i < IPPROTO_MAX; i++) 233 ip6_protox[i] = pr - inet6sw; 234 /* 235 * Cycle through IP protocols and put them into the appropriate place 236 * in ip6_protox[]. 237 */ 238 for (pr = inet6domain.dom_protosw; 239 pr < inet6domain.dom_protoswNPROTOSW; pr++) 240 if (pr->pr_domain->dom_family == PF_INET6 && 241 pr->pr_protocol && pr->pr_protocol != IPPROTO_RAW) { 242 /* Be careful to only index valid IP protocols. */ 243 if (pr->pr_protocol < IPPROTO_MAX) 244 ip6_protox[pr->pr_protocol] = pr - inet6sw; 245 } 246 247 netisr_register(&ip6_nh); 248 #ifdef RSS 249 netisr_register(&ip6_direct_nh); 250 #endif 251 } 252 253 /* 254 * The protocol to be inserted into ip6_protox[] must be already registered 255 * in inet6sw[], either statically or through pf_proto_register(). 256 */ 257 int 258 ip6proto_register(short ip6proto) 259 { 260 struct protosw *pr; 261 262 /* Sanity checks. */ 263 if (ip6proto <= 0 || ip6proto >= IPPROTO_MAX) 264 return (EPROTONOSUPPORT); 265 266 /* 267 * The protocol slot must not be occupied by another protocol 268 * already. An index pointing to IPPROTO_RAW is unused. 269 */ 270 pr = pffindproto(PF_INET6, IPPROTO_RAW, SOCK_RAW); 271 if (pr == NULL) 272 return (EPFNOSUPPORT); 273 if (ip6_protox[ip6proto] != pr - inet6sw) /* IPPROTO_RAW */ 274 return (EEXIST); 275 276 /* 277 * Find the protocol position in inet6sw[] and set the index. 278 */ 279 for (pr = inet6domain.dom_protosw; 280 pr < inet6domain.dom_protoswNPROTOSW; pr++) { 281 if (pr->pr_domain->dom_family == PF_INET6 && 282 pr->pr_protocol && pr->pr_protocol == ip6proto) { 283 ip6_protox[pr->pr_protocol] = pr - inet6sw; 284 return (0); 285 } 286 } 287 return (EPROTONOSUPPORT); 288 } 289 290 int 291 ip6proto_unregister(short ip6proto) 292 { 293 struct protosw *pr; 294 295 /* Sanity checks. */ 296 if (ip6proto <= 0 || ip6proto >= IPPROTO_MAX) 297 return (EPROTONOSUPPORT); 298 299 /* Check if the protocol was indeed registered. */ 300 pr = pffindproto(PF_INET6, IPPROTO_RAW, SOCK_RAW); 301 if (pr == NULL) 302 return (EPFNOSUPPORT); 303 if (ip6_protox[ip6proto] == pr - inet6sw) /* IPPROTO_RAW */ 304 return (ENOENT); 305 306 /* Reset the protocol slot to IPPROTO_RAW. */ 307 ip6_protox[ip6proto] = pr - inet6sw; 308 return (0); 309 } 310 311 #ifdef VIMAGE 312 void 313 ip6_destroy() 314 { 315 int error; 316 317 if ((error = pfil_head_unregister(&V_inet6_pfil_hook)) != 0) 318 printf("%s: WARNING: unable to unregister pfil hook, " 319 "error %d\n", __func__, error); 320 error = hhook_head_deregister(V_ipsec_hhh_in[HHOOK_IPSEC_INET6]); 321 if (error != 0) { 322 printf("%s: WARNING: unable to deregister input helper hook " 323 "type HHOOK_TYPE_IPSEC_IN, id HHOOK_IPSEC_INET6: " 324 "error %d returned\n", __func__, error); 325 } 326 error = hhook_head_deregister(V_ipsec_hhh_out[HHOOK_IPSEC_INET6]); 327 if (error != 0) { 328 printf("%s: WARNING: unable to deregister output helper hook " 329 "type HHOOK_TYPE_IPSEC_OUT, id HHOOK_IPSEC_INET6: " 330 "error %d returned\n", __func__, error); 331 } 332 hashdestroy(V_in6_ifaddrhashtbl, M_IFADDR, V_in6_ifaddrhmask); 333 nd6_destroy(); 334 callout_drain(&V_in6_tmpaddrtimer_ch); 335 } 336 #endif 337 338 static int 339 ip6_init2_vnet(const void *unused __unused) 340 { 341 342 /* nd6_timer_init */ 343 callout_init(&V_nd6_timer_ch, 0); 344 callout_reset(&V_nd6_timer_ch, hz, nd6_timer, curvnet); 345 346 /* timer for regeneranation of temporary addresses randomize ID */ 347 callout_init(&V_in6_tmpaddrtimer_ch, 0); 348 callout_reset(&V_in6_tmpaddrtimer_ch, 349 (V_ip6_temp_preferred_lifetime - V_ip6_desync_factor - 350 V_ip6_temp_regen_advance) * hz, 351 in6_tmpaddrtimer, curvnet); 352 353 return (0); 354 } 355 356 static void 357 ip6_init2(void *dummy) 358 { 359 360 ip6_init2_vnet(NULL); 361 } 362 363 /* cheat */ 364 /* This must be after route_init(), which is now SI_ORDER_THIRD */ 365 SYSINIT(netinet6init2, SI_SUB_PROTO_DOMAIN, SI_ORDER_MIDDLE, ip6_init2, NULL); 366 367 static int 368 ip6_input_hbh(struct mbuf *m, uint32_t *plen, uint32_t *rtalert, int *off, 369 int *nxt, int *ours) 370 { 371 struct ip6_hdr *ip6; 372 struct ip6_hbh *hbh; 373 374 if (ip6_hopopts_input(plen, rtalert, &m, off)) { 375 #if 0 /*touches NULL pointer*/ 376 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard); 377 #endif 378 goto out; /* m have already been freed */ 379 } 380 381 /* adjust pointer */ 382 ip6 = mtod(m, struct ip6_hdr *); 383 384 /* 385 * if the payload length field is 0 and the next header field 386 * indicates Hop-by-Hop Options header, then a Jumbo Payload 387 * option MUST be included. 388 */ 389 if (ip6->ip6_plen == 0 && *plen == 0) { 390 /* 391 * Note that if a valid jumbo payload option is 392 * contained, ip6_hopopts_input() must set a valid 393 * (non-zero) payload length to the variable plen. 394 */ 395 IP6STAT_INC(ip6s_badoptions); 396 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard); 397 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_hdrerr); 398 icmp6_error(m, ICMP6_PARAM_PROB, 399 ICMP6_PARAMPROB_HEADER, 400 (caddr_t)&ip6->ip6_plen - (caddr_t)ip6); 401 goto out; 402 } 403 #ifndef PULLDOWN_TEST 404 /* ip6_hopopts_input() ensures that mbuf is contiguous */ 405 hbh = (struct ip6_hbh *)(ip6 + 1); 406 #else 407 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, sizeof(struct ip6_hdr), 408 sizeof(struct ip6_hbh)); 409 if (hbh == NULL) { 410 IP6STAT_INC(ip6s_tooshort); 411 goto out; 412 } 413 #endif 414 *nxt = hbh->ip6h_nxt; 415 416 /* 417 * If we are acting as a router and the packet contains a 418 * router alert option, see if we know the option value. 419 * Currently, we only support the option value for MLD, in which 420 * case we should pass the packet to the multicast routing 421 * daemon. 422 */ 423 if (*rtalert != ~0) { 424 switch (*rtalert) { 425 case IP6OPT_RTALERT_MLD: 426 if (V_ip6_forwarding) 427 *ours = 1; 428 break; 429 default: 430 /* 431 * RFC2711 requires unrecognized values must be 432 * silently ignored. 433 */ 434 break; 435 } 436 } 437 438 return (0); 439 440 out: 441 return (1); 442 } 443 444 #ifdef RSS 445 /* 446 * IPv6 direct input routine. 447 * 448 * This is called when reinjecting completed fragments where 449 * all of the previous checking and book-keeping has been done. 450 */ 451 void 452 ip6_direct_input(struct mbuf *m) 453 { 454 int off, nxt; 455 int nest; 456 struct m_tag *mtag; 457 struct ip6_direct_ctx *ip6dc; 458 459 mtag = m_tag_locate(m, MTAG_ABI_IPV6, IPV6_TAG_DIRECT, NULL); 460 KASSERT(mtag != NULL, ("Reinjected packet w/o direct ctx tag!")); 461 462 ip6dc = (struct ip6_direct_ctx *)(mtag + 1); 463 nxt = ip6dc->ip6dc_nxt; 464 off = ip6dc->ip6dc_off; 465 466 nest = 0; 467 468 m_tag_delete(m, mtag); 469 470 while (nxt != IPPROTO_DONE) { 471 if (V_ip6_hdrnestlimit && (++nest > V_ip6_hdrnestlimit)) { 472 IP6STAT_INC(ip6s_toomanyhdr); 473 goto bad; 474 } 475 476 /* 477 * protection against faulty packet - there should be 478 * more sanity checks in header chain processing. 479 */ 480 if (m->m_pkthdr.len < off) { 481 IP6STAT_INC(ip6s_tooshort); 482 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_truncated); 483 goto bad; 484 } 485 486 #ifdef IPSEC 487 /* 488 * enforce IPsec policy checking if we are seeing last header. 489 * note that we do not visit this with protocols with pcb layer 490 * code - like udp/tcp/raw ip. 491 */ 492 if (ip6_ipsec_input(m, nxt)) 493 goto bad; 494 #endif /* IPSEC */ 495 496 nxt = (*inet6sw[ip6_protox[nxt]].pr_input)(&m, &off, nxt); 497 } 498 return; 499 bad: 500 m_freem(m); 501 } 502 #endif 503 504 void 505 ip6_input(struct mbuf *m) 506 { 507 struct in6_addr odst; 508 struct ip6_hdr *ip6; 509 struct in6_ifaddr *ia; 510 u_int32_t plen; 511 u_int32_t rtalert = ~0; 512 int off = sizeof(struct ip6_hdr), nest; 513 int nxt, ours = 0; 514 int srcrt = 0; 515 516 #ifdef IPSEC 517 /* 518 * should the inner packet be considered authentic? 519 * see comment in ah4_input(). 520 * NB: m cannot be NULL when passed to the input routine 521 */ 522 523 m->m_flags &= ~M_AUTHIPHDR; 524 m->m_flags &= ~M_AUTHIPDGM; 525 526 #endif /* IPSEC */ 527 528 if (m->m_flags & M_FASTFWD_OURS) { 529 /* 530 * Firewall changed destination to local. 531 */ 532 m->m_flags &= ~M_FASTFWD_OURS; 533 ours = 1; 534 ip6 = mtod(m, struct ip6_hdr *); 535 goto hbhcheck; 536 } 537 538 /* 539 * mbuf statistics 540 */ 541 if (m->m_flags & M_EXT) { 542 if (m->m_next) 543 IP6STAT_INC(ip6s_mext2m); 544 else 545 IP6STAT_INC(ip6s_mext1); 546 } else { 547 if (m->m_next) { 548 if (m->m_flags & M_LOOP) { 549 IP6STAT_INC(ip6s_m2m[V_loif->if_index]); 550 } else if (m->m_pkthdr.rcvif->if_index < IP6S_M2MMAX) 551 IP6STAT_INC( 552 ip6s_m2m[m->m_pkthdr.rcvif->if_index]); 553 else 554 IP6STAT_INC(ip6s_m2m[0]); 555 } else 556 IP6STAT_INC(ip6s_m1); 557 } 558 559 /* drop the packet if IPv6 operation is disabled on the IF */ 560 if ((ND_IFINFO(m->m_pkthdr.rcvif)->flags & ND6_IFF_IFDISABLED)) 561 goto bad; 562 563 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_receive); 564 IP6STAT_INC(ip6s_total); 565 566 #ifndef PULLDOWN_TEST 567 /* 568 * L2 bridge code and some other code can return mbuf chain 569 * that does not conform to KAME requirement. too bad. 570 * XXX: fails to join if interface MTU > MCLBYTES. jumbogram? 571 */ 572 if (m && m->m_next != NULL && m->m_pkthdr.len < MCLBYTES) { 573 struct mbuf *n; 574 575 if (m->m_pkthdr.len > MHLEN) 576 n = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR); 577 else 578 n = m_gethdr(M_NOWAIT, MT_DATA); 579 if (n == NULL) { 580 m_freem(m); 581 return; /* ENOBUFS */ 582 } 583 584 m_move_pkthdr(n, m); 585 m_copydata(m, 0, n->m_pkthdr.len, mtod(n, caddr_t)); 586 n->m_len = n->m_pkthdr.len; 587 m_freem(m); 588 m = n; 589 } 590 IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), /* nothing */); 591 #endif 592 593 if (m->m_len < sizeof(struct ip6_hdr)) { 594 struct ifnet *inifp; 595 inifp = m->m_pkthdr.rcvif; 596 if ((m = m_pullup(m, sizeof(struct ip6_hdr))) == NULL) { 597 IP6STAT_INC(ip6s_toosmall); 598 in6_ifstat_inc(inifp, ifs6_in_hdrerr); 599 return; 600 } 601 } 602 603 ip6 = mtod(m, struct ip6_hdr *); 604 605 if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) { 606 IP6STAT_INC(ip6s_badvers); 607 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_hdrerr); 608 goto bad; 609 } 610 611 IP6STAT_INC(ip6s_nxthist[ip6->ip6_nxt]); 612 613 IP_PROBE(receive, NULL, NULL, ip6, m->m_pkthdr.rcvif, NULL, ip6); 614 615 /* 616 * Check against address spoofing/corruption. 617 */ 618 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_src) || 619 IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_dst)) { 620 /* 621 * XXX: "badscope" is not very suitable for a multicast source. 622 */ 623 IP6STAT_INC(ip6s_badscope); 624 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr); 625 goto bad; 626 } 627 if (IN6_IS_ADDR_MC_INTFACELOCAL(&ip6->ip6_dst) && 628 !(m->m_flags & M_LOOP)) { 629 /* 630 * In this case, the packet should come from the loopback 631 * interface. However, we cannot just check the if_flags, 632 * because ip6_mloopback() passes the "actual" interface 633 * as the outgoing/incoming interface. 634 */ 635 IP6STAT_INC(ip6s_badscope); 636 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr); 637 goto bad; 638 } 639 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) && 640 IPV6_ADDR_MC_SCOPE(&ip6->ip6_dst) == 0) { 641 /* 642 * RFC4291 2.7: 643 * Nodes must not originate a packet to a multicast address 644 * whose scop field contains the reserved value 0; if such 645 * a packet is received, it must be silently dropped. 646 */ 647 IP6STAT_INC(ip6s_badscope); 648 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr); 649 goto bad; 650 } 651 #ifdef ALTQ 652 if (altq_input != NULL && (*altq_input)(m, AF_INET6) == 0) { 653 /* packet is dropped by traffic conditioner */ 654 return; 655 } 656 #endif 657 /* 658 * The following check is not documented in specs. A malicious 659 * party may be able to use IPv4 mapped addr to confuse tcp/udp stack 660 * and bypass security checks (act as if it was from 127.0.0.1 by using 661 * IPv6 src ::ffff:127.0.0.1). Be cautious. 662 * 663 * This check chokes if we are in an SIIT cloud. As none of BSDs 664 * support IPv4-less kernel compilation, we cannot support SIIT 665 * environment at all. So, it makes more sense for us to reject any 666 * malicious packets for non-SIIT environment, than try to do a 667 * partial support for SIIT environment. 668 */ 669 if (IN6_IS_ADDR_V4MAPPED(&ip6->ip6_src) || 670 IN6_IS_ADDR_V4MAPPED(&ip6->ip6_dst)) { 671 IP6STAT_INC(ip6s_badscope); 672 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr); 673 goto bad; 674 } 675 #if 0 676 /* 677 * Reject packets with IPv4 compatible addresses (auto tunnel). 678 * 679 * The code forbids auto tunnel relay case in RFC1933 (the check is 680 * stronger than RFC1933). We may want to re-enable it if mech-xx 681 * is revised to forbid relaying case. 682 */ 683 if (IN6_IS_ADDR_V4COMPAT(&ip6->ip6_src) || 684 IN6_IS_ADDR_V4COMPAT(&ip6->ip6_dst)) { 685 IP6STAT_INC(ip6s_badscope); 686 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr); 687 goto bad; 688 } 689 #endif 690 #ifdef IPSEC 691 /* 692 * Bypass packet filtering for packets previously handled by IPsec. 693 */ 694 if (ip6_ipsec_filtertunnel(m)) 695 goto passin; 696 #endif /* IPSEC */ 697 698 /* 699 * Run through list of hooks for input packets. 700 * 701 * NB: Beware of the destination address changing 702 * (e.g. by NAT rewriting). When this happens, 703 * tell ip6_forward to do the right thing. 704 */ 705 odst = ip6->ip6_dst; 706 707 /* Jump over all PFIL processing if hooks are not active. */ 708 if (!PFIL_HOOKED(&V_inet6_pfil_hook)) 709 goto passin; 710 711 if (pfil_run_hooks(&V_inet6_pfil_hook, &m, 712 m->m_pkthdr.rcvif, PFIL_IN, NULL)) 713 return; 714 if (m == NULL) /* consumed by filter */ 715 return; 716 ip6 = mtod(m, struct ip6_hdr *); 717 srcrt = !IN6_ARE_ADDR_EQUAL(&odst, &ip6->ip6_dst); 718 719 if (m->m_flags & M_FASTFWD_OURS) { 720 m->m_flags &= ~M_FASTFWD_OURS; 721 ours = 1; 722 goto hbhcheck; 723 } 724 if ((m->m_flags & M_IP6_NEXTHOP) && 725 m_tag_find(m, PACKET_TAG_IPFORWARD, NULL) != NULL) { 726 /* 727 * Directly ship the packet on. This allows forwarding 728 * packets originally destined to us to some other directly 729 * connected host. 730 */ 731 ip6_forward(m, 1); 732 return; 733 } 734 735 passin: 736 /* 737 * Disambiguate address scope zones (if there is ambiguity). 738 * We first make sure that the original source or destination address 739 * is not in our internal form for scoped addresses. Such addresses 740 * are not necessarily invalid spec-wise, but we cannot accept them due 741 * to the usage conflict. 742 * in6_setscope() then also checks and rejects the cases where src or 743 * dst are the loopback address and the receiving interface 744 * is not loopback. 745 */ 746 if (in6_clearscope(&ip6->ip6_src) || in6_clearscope(&ip6->ip6_dst)) { 747 IP6STAT_INC(ip6s_badscope); /* XXX */ 748 goto bad; 749 } 750 if (in6_setscope(&ip6->ip6_src, m->m_pkthdr.rcvif, NULL) || 751 in6_setscope(&ip6->ip6_dst, m->m_pkthdr.rcvif, NULL)) { 752 IP6STAT_INC(ip6s_badscope); 753 goto bad; 754 } 755 /* 756 * Multicast check. Assume packet is for us to avoid 757 * prematurely taking locks. 758 */ 759 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 760 ours = 1; 761 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mcast); 762 goto hbhcheck; 763 } 764 /* 765 * Unicast check 766 * XXX: For now we keep link-local IPv6 addresses with embedded 767 * scope zone id, therefore we use zero zoneid here. 768 */ 769 ia = in6ifa_ifwithaddr(&ip6->ip6_dst, 0 /* XXX */); 770 if (ia != NULL) { 771 if (ia->ia6_flags & IN6_IFF_NOTREADY) { 772 char ip6bufs[INET6_ADDRSTRLEN]; 773 char ip6bufd[INET6_ADDRSTRLEN]; 774 /* address is not ready, so discard the packet. */ 775 nd6log((LOG_INFO, 776 "ip6_input: packet to an unready address %s->%s\n", 777 ip6_sprintf(ip6bufs, &ip6->ip6_src), 778 ip6_sprintf(ip6bufd, &ip6->ip6_dst))); 779 ifa_free(&ia->ia_ifa); 780 goto bad; 781 } 782 /* Count the packet in the ip address stats */ 783 counter_u64_add(ia->ia_ifa.ifa_ipackets, 1); 784 counter_u64_add(ia->ia_ifa.ifa_ibytes, m->m_pkthdr.len); 785 ifa_free(&ia->ia_ifa); 786 ours = 1; 787 goto hbhcheck; 788 } 789 790 /* 791 * Now there is no reason to process the packet if it's not our own 792 * and we're not a router. 793 */ 794 if (!V_ip6_forwarding) { 795 IP6STAT_INC(ip6s_cantforward); 796 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard); 797 goto bad; 798 } 799 800 hbhcheck: 801 /* 802 * Process Hop-by-Hop options header if it's contained. 803 * m may be modified in ip6_hopopts_input(). 804 * If a JumboPayload option is included, plen will also be modified. 805 */ 806 plen = (u_int32_t)ntohs(ip6->ip6_plen); 807 if (ip6->ip6_nxt == IPPROTO_HOPOPTS) { 808 if (ip6_input_hbh(m, &plen, &rtalert, &off, &nxt, &ours) != 0) 809 return; 810 } else 811 nxt = ip6->ip6_nxt; 812 813 /* 814 * Use mbuf flags to propagate Router Alert option to 815 * ICMPv6 layer, as hop-by-hop options have been stripped. 816 */ 817 if (rtalert != ~0) 818 m->m_flags |= M_RTALERT_MLD; 819 820 /* 821 * Check that the amount of data in the buffers 822 * is as at least much as the IPv6 header would have us expect. 823 * Trim mbufs if longer than we expect. 824 * Drop packet if shorter than we expect. 825 */ 826 if (m->m_pkthdr.len - sizeof(struct ip6_hdr) < plen) { 827 IP6STAT_INC(ip6s_tooshort); 828 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_truncated); 829 goto bad; 830 } 831 if (m->m_pkthdr.len > sizeof(struct ip6_hdr) + plen) { 832 if (m->m_len == m->m_pkthdr.len) { 833 m->m_len = sizeof(struct ip6_hdr) + plen; 834 m->m_pkthdr.len = sizeof(struct ip6_hdr) + plen; 835 } else 836 m_adj(m, sizeof(struct ip6_hdr) + plen - m->m_pkthdr.len); 837 } 838 839 /* 840 * Forward if desirable. 841 */ 842 if (V_ip6_mrouter && 843 IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 844 /* 845 * If we are acting as a multicast router, all 846 * incoming multicast packets are passed to the 847 * kernel-level multicast forwarding function. 848 * The packet is returned (relatively) intact; if 849 * ip6_mforward() returns a non-zero value, the packet 850 * must be discarded, else it may be accepted below. 851 * 852 * XXX TODO: Check hlim and multicast scope here to avoid 853 * unnecessarily calling into ip6_mforward(). 854 */ 855 if (ip6_mforward && 856 ip6_mforward(ip6, m->m_pkthdr.rcvif, m)) { 857 IP6STAT_INC(ip6s_cantforward); 858 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard); 859 goto bad; 860 } 861 } else if (!ours) { 862 ip6_forward(m, srcrt); 863 return; 864 } 865 866 ip6 = mtod(m, struct ip6_hdr *); 867 868 /* 869 * Malicious party may be able to use IPv4 mapped addr to confuse 870 * tcp/udp stack and bypass security checks (act as if it was from 871 * 127.0.0.1 by using IPv6 src ::ffff:127.0.0.1). Be cautious. 872 * 873 * For SIIT end node behavior, you may want to disable the check. 874 * However, you will become vulnerable to attacks using IPv4 mapped 875 * source. 876 */ 877 if (IN6_IS_ADDR_V4MAPPED(&ip6->ip6_src) || 878 IN6_IS_ADDR_V4MAPPED(&ip6->ip6_dst)) { 879 IP6STAT_INC(ip6s_badscope); 880 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr); 881 goto bad; 882 } 883 884 /* 885 * Tell launch routine the next header 886 */ 887 IP6STAT_INC(ip6s_delivered); 888 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_deliver); 889 nest = 0; 890 891 while (nxt != IPPROTO_DONE) { 892 if (V_ip6_hdrnestlimit && (++nest > V_ip6_hdrnestlimit)) { 893 IP6STAT_INC(ip6s_toomanyhdr); 894 goto bad; 895 } 896 897 /* 898 * protection against faulty packet - there should be 899 * more sanity checks in header chain processing. 900 */ 901 if (m->m_pkthdr.len < off) { 902 IP6STAT_INC(ip6s_tooshort); 903 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_truncated); 904 goto bad; 905 } 906 907 #ifdef IPSEC 908 /* 909 * enforce IPsec policy checking if we are seeing last header. 910 * note that we do not visit this with protocols with pcb layer 911 * code - like udp/tcp/raw ip. 912 */ 913 if (ip6_ipsec_input(m, nxt)) 914 goto bad; 915 #endif /* IPSEC */ 916 917 nxt = (*inet6sw[ip6_protox[nxt]].pr_input)(&m, &off, nxt); 918 } 919 return; 920 bad: 921 m_freem(m); 922 } 923 924 /* 925 * Hop-by-Hop options header processing. If a valid jumbo payload option is 926 * included, the real payload length will be stored in plenp. 927 * 928 * rtalertp - XXX: should be stored more smart way 929 */ 930 static int 931 ip6_hopopts_input(u_int32_t *plenp, u_int32_t *rtalertp, 932 struct mbuf **mp, int *offp) 933 { 934 struct mbuf *m = *mp; 935 int off = *offp, hbhlen; 936 struct ip6_hbh *hbh; 937 938 /* validation of the length of the header */ 939 #ifndef PULLDOWN_TEST 940 IP6_EXTHDR_CHECK(m, off, sizeof(*hbh), -1); 941 hbh = (struct ip6_hbh *)(mtod(m, caddr_t) + off); 942 hbhlen = (hbh->ip6h_len + 1) << 3; 943 944 IP6_EXTHDR_CHECK(m, off, hbhlen, -1); 945 hbh = (struct ip6_hbh *)(mtod(m, caddr_t) + off); 946 #else 947 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, 948 sizeof(struct ip6_hdr), sizeof(struct ip6_hbh)); 949 if (hbh == NULL) { 950 IP6STAT_INC(ip6s_tooshort); 951 return -1; 952 } 953 hbhlen = (hbh->ip6h_len + 1) << 3; 954 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, sizeof(struct ip6_hdr), 955 hbhlen); 956 if (hbh == NULL) { 957 IP6STAT_INC(ip6s_tooshort); 958 return -1; 959 } 960 #endif 961 off += hbhlen; 962 hbhlen -= sizeof(struct ip6_hbh); 963 if (ip6_process_hopopts(m, (u_int8_t *)hbh + sizeof(struct ip6_hbh), 964 hbhlen, rtalertp, plenp) < 0) 965 return (-1); 966 967 *offp = off; 968 *mp = m; 969 return (0); 970 } 971 972 /* 973 * Search header for all Hop-by-hop options and process each option. 974 * This function is separate from ip6_hopopts_input() in order to 975 * handle a case where the sending node itself process its hop-by-hop 976 * options header. In such a case, the function is called from ip6_output(). 977 * 978 * The function assumes that hbh header is located right after the IPv6 header 979 * (RFC2460 p7), opthead is pointer into data content in m, and opthead to 980 * opthead + hbhlen is located in contiguous memory region. 981 */ 982 int 983 ip6_process_hopopts(struct mbuf *m, u_int8_t *opthead, int hbhlen, 984 u_int32_t *rtalertp, u_int32_t *plenp) 985 { 986 struct ip6_hdr *ip6; 987 int optlen = 0; 988 u_int8_t *opt = opthead; 989 u_int16_t rtalert_val; 990 u_int32_t jumboplen; 991 const int erroff = sizeof(struct ip6_hdr) + sizeof(struct ip6_hbh); 992 993 for (; hbhlen > 0; hbhlen -= optlen, opt += optlen) { 994 switch (*opt) { 995 case IP6OPT_PAD1: 996 optlen = 1; 997 break; 998 case IP6OPT_PADN: 999 if (hbhlen < IP6OPT_MINLEN) { 1000 IP6STAT_INC(ip6s_toosmall); 1001 goto bad; 1002 } 1003 optlen = *(opt + 1) + 2; 1004 break; 1005 case IP6OPT_ROUTER_ALERT: 1006 /* XXX may need check for alignment */ 1007 if (hbhlen < IP6OPT_RTALERT_LEN) { 1008 IP6STAT_INC(ip6s_toosmall); 1009 goto bad; 1010 } 1011 if (*(opt + 1) != IP6OPT_RTALERT_LEN - 2) { 1012 /* XXX stat */ 1013 icmp6_error(m, ICMP6_PARAM_PROB, 1014 ICMP6_PARAMPROB_HEADER, 1015 erroff + opt + 1 - opthead); 1016 return (-1); 1017 } 1018 optlen = IP6OPT_RTALERT_LEN; 1019 bcopy((caddr_t)(opt + 2), (caddr_t)&rtalert_val, 2); 1020 *rtalertp = ntohs(rtalert_val); 1021 break; 1022 case IP6OPT_JUMBO: 1023 /* XXX may need check for alignment */ 1024 if (hbhlen < IP6OPT_JUMBO_LEN) { 1025 IP6STAT_INC(ip6s_toosmall); 1026 goto bad; 1027 } 1028 if (*(opt + 1) != IP6OPT_JUMBO_LEN - 2) { 1029 /* XXX stat */ 1030 icmp6_error(m, ICMP6_PARAM_PROB, 1031 ICMP6_PARAMPROB_HEADER, 1032 erroff + opt + 1 - opthead); 1033 return (-1); 1034 } 1035 optlen = IP6OPT_JUMBO_LEN; 1036 1037 /* 1038 * IPv6 packets that have non 0 payload length 1039 * must not contain a jumbo payload option. 1040 */ 1041 ip6 = mtod(m, struct ip6_hdr *); 1042 if (ip6->ip6_plen) { 1043 IP6STAT_INC(ip6s_badoptions); 1044 icmp6_error(m, ICMP6_PARAM_PROB, 1045 ICMP6_PARAMPROB_HEADER, 1046 erroff + opt - opthead); 1047 return (-1); 1048 } 1049 1050 /* 1051 * We may see jumbolen in unaligned location, so 1052 * we'd need to perform bcopy(). 1053 */ 1054 bcopy(opt + 2, &jumboplen, sizeof(jumboplen)); 1055 jumboplen = (u_int32_t)htonl(jumboplen); 1056 1057 #if 1 1058 /* 1059 * if there are multiple jumbo payload options, 1060 * *plenp will be non-zero and the packet will be 1061 * rejected. 1062 * the behavior may need some debate in ipngwg - 1063 * multiple options does not make sense, however, 1064 * there's no explicit mention in specification. 1065 */ 1066 if (*plenp != 0) { 1067 IP6STAT_INC(ip6s_badoptions); 1068 icmp6_error(m, ICMP6_PARAM_PROB, 1069 ICMP6_PARAMPROB_HEADER, 1070 erroff + opt + 2 - opthead); 1071 return (-1); 1072 } 1073 #endif 1074 1075 /* 1076 * jumbo payload length must be larger than 65535. 1077 */ 1078 if (jumboplen <= IPV6_MAXPACKET) { 1079 IP6STAT_INC(ip6s_badoptions); 1080 icmp6_error(m, ICMP6_PARAM_PROB, 1081 ICMP6_PARAMPROB_HEADER, 1082 erroff + opt + 2 - opthead); 1083 return (-1); 1084 } 1085 *plenp = jumboplen; 1086 1087 break; 1088 default: /* unknown option */ 1089 if (hbhlen < IP6OPT_MINLEN) { 1090 IP6STAT_INC(ip6s_toosmall); 1091 goto bad; 1092 } 1093 optlen = ip6_unknown_opt(opt, m, 1094 erroff + opt - opthead); 1095 if (optlen == -1) 1096 return (-1); 1097 optlen += 2; 1098 break; 1099 } 1100 } 1101 1102 return (0); 1103 1104 bad: 1105 m_freem(m); 1106 return (-1); 1107 } 1108 1109 /* 1110 * Unknown option processing. 1111 * The third argument `off' is the offset from the IPv6 header to the option, 1112 * which is necessary if the IPv6 header the and option header and IPv6 header 1113 * is not contiguous in order to return an ICMPv6 error. 1114 */ 1115 int 1116 ip6_unknown_opt(u_int8_t *optp, struct mbuf *m, int off) 1117 { 1118 struct ip6_hdr *ip6; 1119 1120 switch (IP6OPT_TYPE(*optp)) { 1121 case IP6OPT_TYPE_SKIP: /* ignore the option */ 1122 return ((int)*(optp + 1)); 1123 case IP6OPT_TYPE_DISCARD: /* silently discard */ 1124 m_freem(m); 1125 return (-1); 1126 case IP6OPT_TYPE_FORCEICMP: /* send ICMP even if multicasted */ 1127 IP6STAT_INC(ip6s_badoptions); 1128 icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_OPTION, off); 1129 return (-1); 1130 case IP6OPT_TYPE_ICMP: /* send ICMP if not multicasted */ 1131 IP6STAT_INC(ip6s_badoptions); 1132 ip6 = mtod(m, struct ip6_hdr *); 1133 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) || 1134 (m->m_flags & (M_BCAST|M_MCAST))) 1135 m_freem(m); 1136 else 1137 icmp6_error(m, ICMP6_PARAM_PROB, 1138 ICMP6_PARAMPROB_OPTION, off); 1139 return (-1); 1140 } 1141 1142 m_freem(m); /* XXX: NOTREACHED */ 1143 return (-1); 1144 } 1145 1146 /* 1147 * Create the "control" list for this pcb. 1148 * These functions will not modify mbuf chain at all. 1149 * 1150 * With KAME mbuf chain restriction: 1151 * The routine will be called from upper layer handlers like tcp6_input(). 1152 * Thus the routine assumes that the caller (tcp6_input) have already 1153 * called IP6_EXTHDR_CHECK() and all the extension headers are located in the 1154 * very first mbuf on the mbuf chain. 1155 * 1156 * ip6_savecontrol_v4 will handle those options that are possible to be 1157 * set on a v4-mapped socket. 1158 * ip6_savecontrol will directly call ip6_savecontrol_v4 to handle those 1159 * options and handle the v6-only ones itself. 1160 */ 1161 struct mbuf ** 1162 ip6_savecontrol_v4(struct inpcb *inp, struct mbuf *m, struct mbuf **mp, 1163 int *v4only) 1164 { 1165 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1166 1167 #ifdef SO_TIMESTAMP 1168 if ((inp->inp_socket->so_options & SO_TIMESTAMP) != 0) { 1169 struct timeval tv; 1170 1171 microtime(&tv); 1172 *mp = sbcreatecontrol((caddr_t) &tv, sizeof(tv), 1173 SCM_TIMESTAMP, SOL_SOCKET); 1174 if (*mp) 1175 mp = &(*mp)->m_next; 1176 } 1177 #endif 1178 1179 #define IS2292(inp, x, y) (((inp)->inp_flags & IN6P_RFC2292) ? (x) : (y)) 1180 /* RFC 2292 sec. 5 */ 1181 if ((inp->inp_flags & IN6P_PKTINFO) != 0) { 1182 struct in6_pktinfo pi6; 1183 1184 if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) { 1185 #ifdef INET 1186 struct ip *ip; 1187 1188 ip = mtod(m, struct ip *); 1189 pi6.ipi6_addr.s6_addr32[0] = 0; 1190 pi6.ipi6_addr.s6_addr32[1] = 0; 1191 pi6.ipi6_addr.s6_addr32[2] = IPV6_ADDR_INT32_SMP; 1192 pi6.ipi6_addr.s6_addr32[3] = ip->ip_dst.s_addr; 1193 #else 1194 /* We won't hit this code */ 1195 bzero(&pi6.ipi6_addr, sizeof(struct in6_addr)); 1196 #endif 1197 } else { 1198 bcopy(&ip6->ip6_dst, &pi6.ipi6_addr, sizeof(struct in6_addr)); 1199 in6_clearscope(&pi6.ipi6_addr); /* XXX */ 1200 } 1201 pi6.ipi6_ifindex = 1202 (m && m->m_pkthdr.rcvif) ? m->m_pkthdr.rcvif->if_index : 0; 1203 1204 *mp = sbcreatecontrol((caddr_t) &pi6, 1205 sizeof(struct in6_pktinfo), 1206 IS2292(inp, IPV6_2292PKTINFO, IPV6_PKTINFO), IPPROTO_IPV6); 1207 if (*mp) 1208 mp = &(*mp)->m_next; 1209 } 1210 1211 if ((inp->inp_flags & IN6P_HOPLIMIT) != 0) { 1212 int hlim; 1213 1214 if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) { 1215 #ifdef INET 1216 struct ip *ip; 1217 1218 ip = mtod(m, struct ip *); 1219 hlim = ip->ip_ttl; 1220 #else 1221 /* We won't hit this code */ 1222 hlim = 0; 1223 #endif 1224 } else { 1225 hlim = ip6->ip6_hlim & 0xff; 1226 } 1227 *mp = sbcreatecontrol((caddr_t) &hlim, sizeof(int), 1228 IS2292(inp, IPV6_2292HOPLIMIT, IPV6_HOPLIMIT), 1229 IPPROTO_IPV6); 1230 if (*mp) 1231 mp = &(*mp)->m_next; 1232 } 1233 1234 if ((inp->inp_flags & IN6P_TCLASS) != 0) { 1235 int tclass; 1236 1237 if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) { 1238 #ifdef INET 1239 struct ip *ip; 1240 1241 ip = mtod(m, struct ip *); 1242 tclass = ip->ip_tos; 1243 #else 1244 /* We won't hit this code */ 1245 tclass = 0; 1246 #endif 1247 } else { 1248 u_int32_t flowinfo; 1249 1250 flowinfo = (u_int32_t)ntohl(ip6->ip6_flow & IPV6_FLOWINFO_MASK); 1251 flowinfo >>= 20; 1252 tclass = flowinfo & 0xff; 1253 } 1254 *mp = sbcreatecontrol((caddr_t) &tclass, sizeof(int), 1255 IPV6_TCLASS, IPPROTO_IPV6); 1256 if (*mp) 1257 mp = &(*mp)->m_next; 1258 } 1259 1260 if (v4only != NULL) { 1261 if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) { 1262 *v4only = 1; 1263 } else { 1264 *v4only = 0; 1265 } 1266 } 1267 1268 return (mp); 1269 } 1270 1271 void 1272 ip6_savecontrol(struct inpcb *in6p, struct mbuf *m, struct mbuf **mp) 1273 { 1274 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1275 int v4only = 0; 1276 1277 mp = ip6_savecontrol_v4(in6p, m, mp, &v4only); 1278 if (v4only) 1279 return; 1280 1281 /* 1282 * IPV6_HOPOPTS socket option. Recall that we required super-user 1283 * privilege for the option (see ip6_ctloutput), but it might be too 1284 * strict, since there might be some hop-by-hop options which can be 1285 * returned to normal user. 1286 * See also RFC 2292 section 6 (or RFC 3542 section 8). 1287 */ 1288 if ((in6p->inp_flags & IN6P_HOPOPTS) != 0) { 1289 /* 1290 * Check if a hop-by-hop options header is contatined in the 1291 * received packet, and if so, store the options as ancillary 1292 * data. Note that a hop-by-hop options header must be 1293 * just after the IPv6 header, which is assured through the 1294 * IPv6 input processing. 1295 */ 1296 if (ip6->ip6_nxt == IPPROTO_HOPOPTS) { 1297 struct ip6_hbh *hbh; 1298 int hbhlen = 0; 1299 #ifdef PULLDOWN_TEST 1300 struct mbuf *ext; 1301 #endif 1302 1303 #ifndef PULLDOWN_TEST 1304 hbh = (struct ip6_hbh *)(ip6 + 1); 1305 hbhlen = (hbh->ip6h_len + 1) << 3; 1306 #else 1307 ext = ip6_pullexthdr(m, sizeof(struct ip6_hdr), 1308 ip6->ip6_nxt); 1309 if (ext == NULL) { 1310 IP6STAT_INC(ip6s_tooshort); 1311 return; 1312 } 1313 hbh = mtod(ext, struct ip6_hbh *); 1314 hbhlen = (hbh->ip6h_len + 1) << 3; 1315 if (hbhlen != ext->m_len) { 1316 m_freem(ext); 1317 IP6STAT_INC(ip6s_tooshort); 1318 return; 1319 } 1320 #endif 1321 1322 /* 1323 * XXX: We copy the whole header even if a 1324 * jumbo payload option is included, the option which 1325 * is to be removed before returning according to 1326 * RFC2292. 1327 * Note: this constraint is removed in RFC3542 1328 */ 1329 *mp = sbcreatecontrol((caddr_t)hbh, hbhlen, 1330 IS2292(in6p, IPV6_2292HOPOPTS, IPV6_HOPOPTS), 1331 IPPROTO_IPV6); 1332 if (*mp) 1333 mp = &(*mp)->m_next; 1334 #ifdef PULLDOWN_TEST 1335 m_freem(ext); 1336 #endif 1337 } 1338 } 1339 1340 if ((in6p->inp_flags & (IN6P_RTHDR | IN6P_DSTOPTS)) != 0) { 1341 int nxt = ip6->ip6_nxt, off = sizeof(struct ip6_hdr); 1342 1343 /* 1344 * Search for destination options headers or routing 1345 * header(s) through the header chain, and stores each 1346 * header as ancillary data. 1347 * Note that the order of the headers remains in 1348 * the chain of ancillary data. 1349 */ 1350 while (1) { /* is explicit loop prevention necessary? */ 1351 struct ip6_ext *ip6e = NULL; 1352 int elen; 1353 #ifdef PULLDOWN_TEST 1354 struct mbuf *ext = NULL; 1355 #endif 1356 1357 /* 1358 * if it is not an extension header, don't try to 1359 * pull it from the chain. 1360 */ 1361 switch (nxt) { 1362 case IPPROTO_DSTOPTS: 1363 case IPPROTO_ROUTING: 1364 case IPPROTO_HOPOPTS: 1365 case IPPROTO_AH: /* is it possible? */ 1366 break; 1367 default: 1368 goto loopend; 1369 } 1370 1371 #ifndef PULLDOWN_TEST 1372 if (off + sizeof(*ip6e) > m->m_len) 1373 goto loopend; 1374 ip6e = (struct ip6_ext *)(mtod(m, caddr_t) + off); 1375 if (nxt == IPPROTO_AH) 1376 elen = (ip6e->ip6e_len + 2) << 2; 1377 else 1378 elen = (ip6e->ip6e_len + 1) << 3; 1379 if (off + elen > m->m_len) 1380 goto loopend; 1381 #else 1382 ext = ip6_pullexthdr(m, off, nxt); 1383 if (ext == NULL) { 1384 IP6STAT_INC(ip6s_tooshort); 1385 return; 1386 } 1387 ip6e = mtod(ext, struct ip6_ext *); 1388 if (nxt == IPPROTO_AH) 1389 elen = (ip6e->ip6e_len + 2) << 2; 1390 else 1391 elen = (ip6e->ip6e_len + 1) << 3; 1392 if (elen != ext->m_len) { 1393 m_freem(ext); 1394 IP6STAT_INC(ip6s_tooshort); 1395 return; 1396 } 1397 #endif 1398 1399 switch (nxt) { 1400 case IPPROTO_DSTOPTS: 1401 if (!(in6p->inp_flags & IN6P_DSTOPTS)) 1402 break; 1403 1404 *mp = sbcreatecontrol((caddr_t)ip6e, elen, 1405 IS2292(in6p, 1406 IPV6_2292DSTOPTS, IPV6_DSTOPTS), 1407 IPPROTO_IPV6); 1408 if (*mp) 1409 mp = &(*mp)->m_next; 1410 break; 1411 case IPPROTO_ROUTING: 1412 if (!(in6p->inp_flags & IN6P_RTHDR)) 1413 break; 1414 1415 *mp = sbcreatecontrol((caddr_t)ip6e, elen, 1416 IS2292(in6p, IPV6_2292RTHDR, IPV6_RTHDR), 1417 IPPROTO_IPV6); 1418 if (*mp) 1419 mp = &(*mp)->m_next; 1420 break; 1421 case IPPROTO_HOPOPTS: 1422 case IPPROTO_AH: /* is it possible? */ 1423 break; 1424 1425 default: 1426 /* 1427 * other cases have been filtered in the above. 1428 * none will visit this case. here we supply 1429 * the code just in case (nxt overwritten or 1430 * other cases). 1431 */ 1432 #ifdef PULLDOWN_TEST 1433 m_freem(ext); 1434 #endif 1435 goto loopend; 1436 1437 } 1438 1439 /* proceed with the next header. */ 1440 off += elen; 1441 nxt = ip6e->ip6e_nxt; 1442 ip6e = NULL; 1443 #ifdef PULLDOWN_TEST 1444 m_freem(ext); 1445 ext = NULL; 1446 #endif 1447 } 1448 loopend: 1449 ; 1450 } 1451 1452 if (in6p->inp_flags2 & INP_RECVFLOWID) { 1453 uint32_t flowid, flow_type; 1454 1455 flowid = m->m_pkthdr.flowid; 1456 flow_type = M_HASHTYPE_GET(m); 1457 1458 /* 1459 * XXX should handle the failure of one or the 1460 * other - don't populate both? 1461 */ 1462 *mp = sbcreatecontrol((caddr_t) &flowid, 1463 sizeof(uint32_t), IPV6_FLOWID, IPPROTO_IPV6); 1464 if (*mp) 1465 mp = &(*mp)->m_next; 1466 *mp = sbcreatecontrol((caddr_t) &flow_type, 1467 sizeof(uint32_t), IPV6_FLOWTYPE, IPPROTO_IPV6); 1468 if (*mp) 1469 mp = &(*mp)->m_next; 1470 } 1471 1472 #ifdef RSS 1473 if (in6p->inp_flags2 & INP_RECVRSSBUCKETID) { 1474 uint32_t flowid, flow_type; 1475 uint32_t rss_bucketid; 1476 1477 flowid = m->m_pkthdr.flowid; 1478 flow_type = M_HASHTYPE_GET(m); 1479 1480 if (rss_hash2bucket(flowid, flow_type, &rss_bucketid) == 0) { 1481 *mp = sbcreatecontrol((caddr_t) &rss_bucketid, 1482 sizeof(uint32_t), IPV6_RSSBUCKETID, IPPROTO_IPV6); 1483 if (*mp) 1484 mp = &(*mp)->m_next; 1485 } 1486 } 1487 #endif 1488 1489 } 1490 #undef IS2292 1491 1492 void 1493 ip6_notify_pmtu(struct inpcb *inp, struct sockaddr_in6 *dst, u_int32_t mtu) 1494 { 1495 struct socket *so; 1496 struct mbuf *m_mtu; 1497 struct ip6_mtuinfo mtuctl; 1498 1499 KASSERT(inp != NULL, ("%s: inp == NULL", __func__)); 1500 /* 1501 * Notify the error by sending IPV6_PATHMTU ancillary data if 1502 * application wanted to know the MTU value. 1503 * NOTE: we notify disconnected sockets, because some udp 1504 * applications keep sending sockets disconnected. 1505 * NOTE: our implementation doesn't notify connected sockets that has 1506 * foreign address that is different than given destination addresses 1507 * (this is permitted by RFC 3542). 1508 */ 1509 if ((inp->inp_flags & IN6P_MTU) == 0 || ( 1510 !IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr) && 1511 !IN6_ARE_ADDR_EQUAL(&inp->in6p_faddr, &dst->sin6_addr))) 1512 return; 1513 1514 mtuctl.ip6m_mtu = mtu; 1515 mtuctl.ip6m_addr = *dst; 1516 if (sa6_recoverscope(&mtuctl.ip6m_addr)) 1517 return; 1518 1519 if ((m_mtu = sbcreatecontrol((caddr_t)&mtuctl, sizeof(mtuctl), 1520 IPV6_PATHMTU, IPPROTO_IPV6)) == NULL) 1521 return; 1522 1523 so = inp->inp_socket; 1524 if (sbappendaddr(&so->so_rcv, (struct sockaddr *)dst, NULL, m_mtu) 1525 == 0) { 1526 m_freem(m_mtu); 1527 /* XXX: should count statistics */ 1528 } else 1529 sorwakeup(so); 1530 } 1531 1532 #ifdef PULLDOWN_TEST 1533 /* 1534 * pull single extension header from mbuf chain. returns single mbuf that 1535 * contains the result, or NULL on error. 1536 */ 1537 static struct mbuf * 1538 ip6_pullexthdr(struct mbuf *m, size_t off, int nxt) 1539 { 1540 struct ip6_ext ip6e; 1541 size_t elen; 1542 struct mbuf *n; 1543 1544 #ifdef DIAGNOSTIC 1545 switch (nxt) { 1546 case IPPROTO_DSTOPTS: 1547 case IPPROTO_ROUTING: 1548 case IPPROTO_HOPOPTS: 1549 case IPPROTO_AH: /* is it possible? */ 1550 break; 1551 default: 1552 printf("ip6_pullexthdr: invalid nxt=%d\n", nxt); 1553 } 1554 #endif 1555 1556 m_copydata(m, off, sizeof(ip6e), (caddr_t)&ip6e); 1557 if (nxt == IPPROTO_AH) 1558 elen = (ip6e.ip6e_len + 2) << 2; 1559 else 1560 elen = (ip6e.ip6e_len + 1) << 3; 1561 1562 if (elen > MLEN) 1563 n = m_getcl(M_NOWAIT, MT_DATA, 0); 1564 else 1565 n = m_get(M_NOWAIT, MT_DATA); 1566 if (n == NULL) 1567 return NULL; 1568 1569 m_copydata(m, off, elen, mtod(n, caddr_t)); 1570 n->m_len = elen; 1571 return n; 1572 } 1573 #endif 1574 1575 /* 1576 * Get pointer to the previous header followed by the header 1577 * currently processed. 1578 * XXX: This function supposes that 1579 * M includes all headers, 1580 * the next header field and the header length field of each header 1581 * are valid, and 1582 * the sum of each header length equals to OFF. 1583 * Because of these assumptions, this function must be called very 1584 * carefully. Moreover, it will not be used in the near future when 1585 * we develop `neater' mechanism to process extension headers. 1586 */ 1587 char * 1588 ip6_get_prevhdr(const struct mbuf *m, int off) 1589 { 1590 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1591 1592 if (off == sizeof(struct ip6_hdr)) 1593 return (&ip6->ip6_nxt); 1594 else { 1595 int len, nxt; 1596 struct ip6_ext *ip6e = NULL; 1597 1598 nxt = ip6->ip6_nxt; 1599 len = sizeof(struct ip6_hdr); 1600 while (len < off) { 1601 ip6e = (struct ip6_ext *)(mtod(m, caddr_t) + len); 1602 1603 switch (nxt) { 1604 case IPPROTO_FRAGMENT: 1605 len += sizeof(struct ip6_frag); 1606 break; 1607 case IPPROTO_AH: 1608 len += (ip6e->ip6e_len + 2) << 2; 1609 break; 1610 default: 1611 len += (ip6e->ip6e_len + 1) << 3; 1612 break; 1613 } 1614 nxt = ip6e->ip6e_nxt; 1615 } 1616 if (ip6e) 1617 return (&ip6e->ip6e_nxt); 1618 else 1619 return NULL; 1620 } 1621 } 1622 1623 /* 1624 * get next header offset. m will be retained. 1625 */ 1626 int 1627 ip6_nexthdr(const struct mbuf *m, int off, int proto, int *nxtp) 1628 { 1629 struct ip6_hdr ip6; 1630 struct ip6_ext ip6e; 1631 struct ip6_frag fh; 1632 1633 /* just in case */ 1634 if (m == NULL) 1635 panic("ip6_nexthdr: m == NULL"); 1636 if ((m->m_flags & M_PKTHDR) == 0 || m->m_pkthdr.len < off) 1637 return -1; 1638 1639 switch (proto) { 1640 case IPPROTO_IPV6: 1641 if (m->m_pkthdr.len < off + sizeof(ip6)) 1642 return -1; 1643 m_copydata(m, off, sizeof(ip6), (caddr_t)&ip6); 1644 if (nxtp) 1645 *nxtp = ip6.ip6_nxt; 1646 off += sizeof(ip6); 1647 return off; 1648 1649 case IPPROTO_FRAGMENT: 1650 /* 1651 * terminate parsing if it is not the first fragment, 1652 * it does not make sense to parse through it. 1653 */ 1654 if (m->m_pkthdr.len < off + sizeof(fh)) 1655 return -1; 1656 m_copydata(m, off, sizeof(fh), (caddr_t)&fh); 1657 /* IP6F_OFF_MASK = 0xfff8(BigEndian), 0xf8ff(LittleEndian) */ 1658 if (fh.ip6f_offlg & IP6F_OFF_MASK) 1659 return -1; 1660 if (nxtp) 1661 *nxtp = fh.ip6f_nxt; 1662 off += sizeof(struct ip6_frag); 1663 return off; 1664 1665 case IPPROTO_AH: 1666 if (m->m_pkthdr.len < off + sizeof(ip6e)) 1667 return -1; 1668 m_copydata(m, off, sizeof(ip6e), (caddr_t)&ip6e); 1669 if (nxtp) 1670 *nxtp = ip6e.ip6e_nxt; 1671 off += (ip6e.ip6e_len + 2) << 2; 1672 return off; 1673 1674 case IPPROTO_HOPOPTS: 1675 case IPPROTO_ROUTING: 1676 case IPPROTO_DSTOPTS: 1677 if (m->m_pkthdr.len < off + sizeof(ip6e)) 1678 return -1; 1679 m_copydata(m, off, sizeof(ip6e), (caddr_t)&ip6e); 1680 if (nxtp) 1681 *nxtp = ip6e.ip6e_nxt; 1682 off += (ip6e.ip6e_len + 1) << 3; 1683 return off; 1684 1685 case IPPROTO_NONE: 1686 case IPPROTO_ESP: 1687 case IPPROTO_IPCOMP: 1688 /* give up */ 1689 return -1; 1690 1691 default: 1692 return -1; 1693 } 1694 1695 /* NOTREACHED */ 1696 } 1697 1698 /* 1699 * get offset for the last header in the chain. m will be kept untainted. 1700 */ 1701 int 1702 ip6_lasthdr(const struct mbuf *m, int off, int proto, int *nxtp) 1703 { 1704 int newoff; 1705 int nxt; 1706 1707 if (!nxtp) { 1708 nxt = -1; 1709 nxtp = &nxt; 1710 } 1711 while (1) { 1712 newoff = ip6_nexthdr(m, off, proto, nxtp); 1713 if (newoff < 0) 1714 return off; 1715 else if (newoff < off) 1716 return -1; /* invalid */ 1717 else if (newoff == off) 1718 return newoff; 1719 1720 off = newoff; 1721 proto = *nxtp; 1722 } 1723 } 1724 1725 /* 1726 * System control for IP6 1727 */ 1728 1729 u_char inet6ctlerrmap[PRC_NCMDS] = { 1730 0, 0, 0, 0, 1731 0, EMSGSIZE, EHOSTDOWN, EHOSTUNREACH, 1732 EHOSTUNREACH, EHOSTUNREACH, ECONNREFUSED, ECONNREFUSED, 1733 EMSGSIZE, EHOSTUNREACH, 0, 0, 1734 0, 0, 0, 0, 1735 ENOPROTOOPT 1736 }; 1737