1 /* $NetBSD: ip6_output.c,v 1.85 2004/07/14 03:06:08 itojun Exp $ */ 2 /* $KAME: ip6_output.c,v 1.172 2001/03/25 09:55:56 itojun Exp $ */ 3 4 /* 5 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the project nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32 33 /* 34 * Copyright (c) 1982, 1986, 1988, 1990, 1993 35 * The Regents of the University of California. All rights reserved. 36 * 37 * Redistribution and use in source and binary forms, with or without 38 * modification, are permitted provided that the following conditions 39 * are met: 40 * 1. Redistributions of source code must retain the above copyright 41 * notice, this list of conditions and the following disclaimer. 42 * 2. Redistributions in binary form must reproduce the above copyright 43 * notice, this list of conditions and the following disclaimer in the 44 * documentation and/or other materials provided with the distribution. 45 * 3. Neither the name of the University nor the names of its contributors 46 * may be used to endorse or promote products derived from this software 47 * without specific prior written permission. 48 * 49 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 50 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 51 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 52 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 53 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 54 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 55 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 56 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 57 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 58 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 59 * SUCH DAMAGE. 60 * 61 * @(#)ip_output.c 8.3 (Berkeley) 1/21/94 62 */ 63 64 #include <sys/cdefs.h> 65 __KERNEL_RCSID(0, "$NetBSD: ip6_output.c,v 1.85 2004/07/14 03:06:08 itojun Exp $"); 66 67 #include "opt_inet.h" 68 #include "opt_ipsec.h" 69 #include "opt_pfil_hooks.h" 70 71 #include <sys/param.h> 72 #include <sys/malloc.h> 73 #include <sys/mbuf.h> 74 #include <sys/errno.h> 75 #include <sys/protosw.h> 76 #include <sys/socket.h> 77 #include <sys/socketvar.h> 78 #include <sys/systm.h> 79 #include <sys/proc.h> 80 81 #include <net/if.h> 82 #include <net/route.h> 83 #ifdef PFIL_HOOKS 84 #include <net/pfil.h> 85 #endif 86 87 #include <netinet/in.h> 88 #include <netinet/in_var.h> 89 #include <netinet/ip6.h> 90 #include <netinet/icmp6.h> 91 #include <netinet6/ip6_var.h> 92 #include <netinet6/in6_pcb.h> 93 #include <netinet6/nd6.h> 94 #include <netinet6/ip6protosw.h> 95 96 #ifdef IPSEC 97 #include <netinet6/ipsec.h> 98 #include <netkey/key.h> 99 #endif /* IPSEC */ 100 101 #include "loop.h" 102 103 #include <net/net_osdep.h> 104 105 #ifdef PFIL_HOOKS 106 extern struct pfil_head inet6_pfil_hook; /* XXX */ 107 #endif 108 109 struct ip6_exthdrs { 110 struct mbuf *ip6e_ip6; 111 struct mbuf *ip6e_hbh; 112 struct mbuf *ip6e_dest1; 113 struct mbuf *ip6e_rthdr; 114 struct mbuf *ip6e_dest2; 115 }; 116 117 static int ip6_pcbopts __P((struct ip6_pktopts **, struct mbuf *, 118 struct socket *)); 119 static int ip6_setmoptions __P((int, struct ip6_moptions **, struct mbuf *)); 120 static int ip6_getmoptions __P((int, struct ip6_moptions *, struct mbuf **)); 121 static int ip6_copyexthdr __P((struct mbuf **, caddr_t, int)); 122 static int ip6_insertfraghdr __P((struct mbuf *, struct mbuf *, int, 123 struct ip6_frag **)); 124 static int ip6_insert_jumboopt __P((struct ip6_exthdrs *, u_int32_t)); 125 static int ip6_splithdr __P((struct mbuf *, struct ip6_exthdrs *)); 126 127 extern struct ifnet loif[NLOOP]; 128 129 /* 130 * IP6 output. The packet in mbuf chain m contains a skeletal IP6 131 * header (with pri, len, nxt, hlim, src, dst). 132 * This function may modify ver and hlim only. 133 * The mbuf chain containing the packet will be freed. 134 * The mbuf opt, if present, will not be freed. 135 * 136 * type of "mtu": rt_rmx.rmx_mtu is u_long, ifnet.ifr_mtu is int, and 137 * nd_ifinfo.linkmtu is u_int32_t. so we use u_long to hold largest one, 138 * which is rt_rmx.rmx_mtu. 139 */ 140 int 141 ip6_output(m0, opt, ro, flags, im6o, so, ifpp) 142 struct mbuf *m0; 143 struct ip6_pktopts *opt; 144 struct route_in6 *ro; 145 int flags; 146 struct ip6_moptions *im6o; 147 struct socket *so; 148 struct ifnet **ifpp; /* XXX: just for statistics */ 149 { 150 struct ip6_hdr *ip6, *mhip6; 151 struct ifnet *ifp, *origifp; 152 struct mbuf *m = m0; 153 int hlen, tlen, len, off; 154 struct route_in6 ip6route; 155 struct sockaddr_in6 *dst; 156 int error = 0; 157 u_long mtu; 158 int alwaysfrag, dontfrag; 159 u_int32_t optlen = 0, plen = 0, unfragpartlen = 0; 160 struct ip6_exthdrs exthdrs; 161 struct in6_addr finaldst; 162 struct route_in6 *ro_pmtu = NULL; 163 int hdrsplit = 0; 164 int needipsec = 0; 165 #ifdef IPSEC 166 int needipsectun = 0; 167 struct secpolicy *sp = NULL; 168 169 ip6 = mtod(m, struct ip6_hdr *); 170 #endif /* IPSEC */ 171 172 #define MAKE_EXTHDR(hp, mp) \ 173 do { \ 174 if (hp) { \ 175 struct ip6_ext *eh = (struct ip6_ext *)(hp); \ 176 error = ip6_copyexthdr((mp), (caddr_t)(hp), \ 177 ((eh)->ip6e_len + 1) << 3); \ 178 if (error) \ 179 goto freehdrs; \ 180 } \ 181 } while (/*CONSTCOND*/ 0) 182 183 bzero(&exthdrs, sizeof(exthdrs)); 184 if (opt) { 185 /* Hop-by-Hop options header */ 186 MAKE_EXTHDR(opt->ip6po_hbh, &exthdrs.ip6e_hbh); 187 /* Destination options header(1st part) */ 188 MAKE_EXTHDR(opt->ip6po_dest1, &exthdrs.ip6e_dest1); 189 /* Routing header */ 190 MAKE_EXTHDR(opt->ip6po_rthdr, &exthdrs.ip6e_rthdr); 191 /* Destination options header(2nd part) */ 192 MAKE_EXTHDR(opt->ip6po_dest2, &exthdrs.ip6e_dest2); 193 } 194 195 #ifdef IPSEC 196 if ((flags & IPV6_FORWARDING) != 0) { 197 needipsec = 0; 198 goto skippolicycheck; 199 } 200 201 /* get a security policy for this packet */ 202 if (so == NULL) 203 sp = ipsec6_getpolicybyaddr(m, IPSEC_DIR_OUTBOUND, 0, &error); 204 else { 205 if (IPSEC_PCB_SKIP_IPSEC(sotoinpcb_hdr(so)->inph_sp, 206 IPSEC_DIR_OUTBOUND)) { 207 needipsec = 0; 208 goto skippolicycheck; 209 } 210 sp = ipsec6_getpolicybysock(m, IPSEC_DIR_OUTBOUND, so, &error); 211 } 212 213 if (sp == NULL) { 214 ipsec6stat.out_inval++; 215 goto freehdrs; 216 } 217 218 error = 0; 219 220 /* check policy */ 221 switch (sp->policy) { 222 case IPSEC_POLICY_DISCARD: 223 /* 224 * This packet is just discarded. 225 */ 226 ipsec6stat.out_polvio++; 227 goto freehdrs; 228 229 case IPSEC_POLICY_BYPASS: 230 case IPSEC_POLICY_NONE: 231 /* no need to do IPsec. */ 232 needipsec = 0; 233 break; 234 235 case IPSEC_POLICY_IPSEC: 236 if (sp->req == NULL) { 237 /* XXX should be panic ? */ 238 printf("ip6_output: No IPsec request specified.\n"); 239 error = EINVAL; 240 goto freehdrs; 241 } 242 needipsec = 1; 243 break; 244 245 case IPSEC_POLICY_ENTRUST: 246 default: 247 printf("ip6_output: Invalid policy found. %d\n", sp->policy); 248 } 249 250 skippolicycheck:; 251 #endif /* IPSEC */ 252 253 /* 254 * Calculate the total length of the extension header chain. 255 * Keep the length of the unfragmentable part for fragmentation. 256 */ 257 optlen = 0; 258 if (exthdrs.ip6e_hbh) optlen += exthdrs.ip6e_hbh->m_len; 259 if (exthdrs.ip6e_dest1) optlen += exthdrs.ip6e_dest1->m_len; 260 if (exthdrs.ip6e_rthdr) optlen += exthdrs.ip6e_rthdr->m_len; 261 unfragpartlen = optlen + sizeof(struct ip6_hdr); 262 /* NOTE: we don't add AH/ESP length here. do that later. */ 263 if (exthdrs.ip6e_dest2) optlen += exthdrs.ip6e_dest2->m_len; 264 265 /* 266 * If we need IPsec, or there is at least one extension header, 267 * separate IP6 header from the payload. 268 */ 269 if ((needipsec || optlen) && !hdrsplit) { 270 if ((error = ip6_splithdr(m, &exthdrs)) != 0) { 271 m = NULL; 272 goto freehdrs; 273 } 274 m = exthdrs.ip6e_ip6; 275 hdrsplit++; 276 } 277 278 /* adjust pointer */ 279 ip6 = mtod(m, struct ip6_hdr *); 280 281 /* adjust mbuf packet header length */ 282 m->m_pkthdr.len += optlen; 283 plen = m->m_pkthdr.len - sizeof(*ip6); 284 285 /* If this is a jumbo payload, insert a jumbo payload option. */ 286 if (plen > IPV6_MAXPACKET) { 287 if (!hdrsplit) { 288 if ((error = ip6_splithdr(m, &exthdrs)) != 0) { 289 m = NULL; 290 goto freehdrs; 291 } 292 m = exthdrs.ip6e_ip6; 293 hdrsplit++; 294 } 295 /* adjust pointer */ 296 ip6 = mtod(m, struct ip6_hdr *); 297 if ((error = ip6_insert_jumboopt(&exthdrs, plen)) != 0) 298 goto freehdrs; 299 ip6->ip6_plen = 0; 300 } else 301 ip6->ip6_plen = htons(plen); 302 303 /* 304 * Concatenate headers and fill in next header fields. 305 * Here we have, on "m" 306 * IPv6 payload 307 * and we insert headers accordingly. Finally, we should be getting: 308 * IPv6 hbh dest1 rthdr ah* [esp* dest2 payload] 309 * 310 * during the header composing process, "m" points to IPv6 header. 311 * "mprev" points to an extension header prior to esp. 312 */ 313 { 314 u_char *nexthdrp = &ip6->ip6_nxt; 315 struct mbuf *mprev = m; 316 317 /* 318 * we treat dest2 specially. this makes IPsec processing 319 * much easier. the goal here is to make mprev point the 320 * mbuf prior to dest2. 321 * 322 * result: IPv6 dest2 payload 323 * m and mprev will point to IPv6 header. 324 */ 325 if (exthdrs.ip6e_dest2) { 326 if (!hdrsplit) 327 panic("assumption failed: hdr not split"); 328 exthdrs.ip6e_dest2->m_next = m->m_next; 329 m->m_next = exthdrs.ip6e_dest2; 330 *mtod(exthdrs.ip6e_dest2, u_char *) = ip6->ip6_nxt; 331 ip6->ip6_nxt = IPPROTO_DSTOPTS; 332 } 333 334 #define MAKE_CHAIN(m, mp, p, i)\ 335 do {\ 336 if (m) {\ 337 if (!hdrsplit) \ 338 panic("assumption failed: hdr not split"); \ 339 *mtod((m), u_char *) = *(p);\ 340 *(p) = (i);\ 341 p = mtod((m), u_char *);\ 342 (m)->m_next = (mp)->m_next;\ 343 (mp)->m_next = (m);\ 344 (mp) = (m);\ 345 }\ 346 } while (/*CONSTCOND*/ 0) 347 /* 348 * result: IPv6 hbh dest1 rthdr dest2 payload 349 * m will point to IPv6 header. mprev will point to the 350 * extension header prior to dest2 (rthdr in the above case). 351 */ 352 MAKE_CHAIN(exthdrs.ip6e_hbh, mprev, nexthdrp, IPPROTO_HOPOPTS); 353 MAKE_CHAIN(exthdrs.ip6e_dest1, mprev, nexthdrp, 354 IPPROTO_DSTOPTS); 355 MAKE_CHAIN(exthdrs.ip6e_rthdr, mprev, nexthdrp, 356 IPPROTO_ROUTING); 357 358 #ifdef IPSEC 359 if (!needipsec) 360 goto skip_ipsec2; 361 362 /* 363 * pointers after IPsec headers are not valid any more. 364 * other pointers need a great care too. 365 * (IPsec routines should not mangle mbufs prior to AH/ESP) 366 */ 367 exthdrs.ip6e_dest2 = NULL; 368 369 { 370 struct ip6_rthdr *rh = NULL; 371 int segleft_org = 0; 372 struct ipsec_output_state state; 373 374 if (exthdrs.ip6e_rthdr) { 375 rh = mtod(exthdrs.ip6e_rthdr, struct ip6_rthdr *); 376 segleft_org = rh->ip6r_segleft; 377 rh->ip6r_segleft = 0; 378 } 379 380 bzero(&state, sizeof(state)); 381 state.m = m; 382 error = ipsec6_output_trans(&state, nexthdrp, mprev, sp, flags, 383 &needipsectun); 384 m = state.m; 385 if (error) { 386 /* mbuf is already reclaimed in ipsec6_output_trans. */ 387 m = NULL; 388 switch (error) { 389 case EHOSTUNREACH: 390 case ENETUNREACH: 391 case EMSGSIZE: 392 case ENOBUFS: 393 case ENOMEM: 394 break; 395 default: 396 printf("ip6_output (ipsec): error code %d\n", error); 397 /* FALLTHROUGH */ 398 case ENOENT: 399 /* don't show these error codes to the user */ 400 error = 0; 401 break; 402 } 403 goto bad; 404 } 405 if (exthdrs.ip6e_rthdr) { 406 /* ah6_output doesn't modify mbuf chain */ 407 rh->ip6r_segleft = segleft_org; 408 } 409 } 410 skip_ipsec2:; 411 #endif 412 } 413 414 /* 415 * If there is a routing header, replace destination address field 416 * with the first hop of the routing header. 417 */ 418 if (exthdrs.ip6e_rthdr) { 419 struct ip6_rthdr *rh; 420 struct ip6_rthdr0 *rh0; 421 struct in6_addr *addr; 422 423 rh = (struct ip6_rthdr *)(mtod(exthdrs.ip6e_rthdr, 424 struct ip6_rthdr *)); 425 finaldst = ip6->ip6_dst; 426 switch (rh->ip6r_type) { 427 case IPV6_RTHDR_TYPE_0: 428 rh0 = (struct ip6_rthdr0 *)rh; 429 addr = (struct in6_addr *)(rh0 + 1); 430 ip6->ip6_dst = addr[0]; 431 bcopy(&addr[1], &addr[0], 432 sizeof(struct in6_addr) * (rh0->ip6r0_segleft - 1)); 433 addr[rh0->ip6r0_segleft - 1] = finaldst; 434 break; 435 default: /* is it possible? */ 436 error = EINVAL; 437 goto bad; 438 } 439 } 440 441 /* Source address validation */ 442 if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) && 443 (flags & IPV6_UNSPECSRC) == 0) { 444 error = EOPNOTSUPP; 445 ip6stat.ip6s_badscope++; 446 goto bad; 447 } 448 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_src)) { 449 error = EOPNOTSUPP; 450 ip6stat.ip6s_badscope++; 451 goto bad; 452 } 453 454 ip6stat.ip6s_localout++; 455 456 /* 457 * Route packet. 458 */ 459 /* initialize cached route */ 460 if (ro == 0) { 461 ro = &ip6route; 462 bzero((caddr_t)ro, sizeof(*ro)); 463 } 464 ro_pmtu = ro; 465 if (opt && opt->ip6po_rthdr) 466 ro = &opt->ip6po_route; 467 dst = (struct sockaddr_in6 *)&ro->ro_dst; 468 /* 469 * If there is a cached route, 470 * check that it is to the same destination 471 * and is still up. If not, free it and try again. 472 */ 473 if (ro->ro_rt && ((ro->ro_rt->rt_flags & RTF_UP) == 0 || 474 dst->sin6_family != AF_INET6 || 475 !IN6_ARE_ADDR_EQUAL(&dst->sin6_addr, &ip6->ip6_dst))) { 476 RTFREE(ro->ro_rt); 477 ro->ro_rt = (struct rtentry *)0; 478 } 479 if (ro->ro_rt == 0) { 480 bzero(dst, sizeof(*dst)); 481 dst->sin6_family = AF_INET6; 482 dst->sin6_len = sizeof(struct sockaddr_in6); 483 dst->sin6_addr = ip6->ip6_dst; 484 } 485 #ifdef IPSEC 486 if (needipsec && needipsectun) { 487 struct ipsec_output_state state; 488 489 /* 490 * All the extension headers will become inaccessible 491 * (since they can be encrypted). 492 * Don't panic, we need no more updates to extension headers 493 * on inner IPv6 packet (since they are now encapsulated). 494 * 495 * IPv6 [ESP|AH] IPv6 [extension headers] payload 496 */ 497 bzero(&exthdrs, sizeof(exthdrs)); 498 exthdrs.ip6e_ip6 = m; 499 500 bzero(&state, sizeof(state)); 501 state.m = m; 502 state.ro = (struct route *)ro; 503 state.dst = (struct sockaddr *)dst; 504 505 error = ipsec6_output_tunnel(&state, sp, flags); 506 507 m = state.m; 508 ro_pmtu = ro = (struct route_in6 *)state.ro; 509 dst = (struct sockaddr_in6 *)state.dst; 510 if (error) { 511 /* mbuf is already reclaimed in ipsec6_output_tunnel. */ 512 m0 = m = NULL; 513 m = NULL; 514 switch (error) { 515 case EHOSTUNREACH: 516 case ENETUNREACH: 517 case EMSGSIZE: 518 case ENOBUFS: 519 case ENOMEM: 520 break; 521 default: 522 printf("ip6_output (ipsec): error code %d\n", error); 523 /* FALLTHROUGH */ 524 case ENOENT: 525 /* don't show these error codes to the user */ 526 error = 0; 527 break; 528 } 529 goto bad; 530 } 531 532 exthdrs.ip6e_ip6 = m; 533 } 534 #endif /* IPSEC */ 535 536 if (!IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 537 /* Unicast */ 538 539 #define ifatoia6(ifa) ((struct in6_ifaddr *)(ifa)) 540 #define sin6tosa(sin6) ((struct sockaddr *)(sin6)) 541 /* xxx 542 * interface selection comes here 543 * if an interface is specified from an upper layer, 544 * ifp must point it. 545 */ 546 if (ro->ro_rt == 0) { 547 /* 548 * non-bsdi always clone routes, if parent is 549 * PRF_CLONING. 550 */ 551 rtalloc((struct route *)ro); 552 } 553 if (ro->ro_rt == 0) { 554 ip6stat.ip6s_noroute++; 555 error = EHOSTUNREACH; 556 /* XXX in6_ifstat_inc(ifp, ifs6_out_discard); */ 557 goto bad; 558 } 559 ifp = ro->ro_rt->rt_ifp; 560 ro->ro_rt->rt_use++; 561 if (ro->ro_rt->rt_flags & RTF_GATEWAY) 562 dst = (struct sockaddr_in6 *)ro->ro_rt->rt_gateway; 563 m->m_flags &= ~(M_BCAST | M_MCAST); /* just in case */ 564 565 in6_ifstat_inc(ifp, ifs6_out_request); 566 567 /* 568 * Check if the outgoing interface conflicts with 569 * the interface specified by ifi6_ifindex (if specified). 570 * Note that loopback interface is always okay. 571 * (this may happen when we are sending a packet to one of 572 * our own addresses.) 573 */ 574 if (opt && opt->ip6po_pktinfo && 575 opt->ip6po_pktinfo->ipi6_ifindex) { 576 if (!(ifp->if_flags & IFF_LOOPBACK) && 577 ifp->if_index != opt->ip6po_pktinfo->ipi6_ifindex) { 578 ip6stat.ip6s_noroute++; 579 in6_ifstat_inc(ifp, ifs6_out_discard); 580 error = EHOSTUNREACH; 581 goto bad; 582 } 583 } 584 585 if (opt && opt->ip6po_hlim != -1) 586 ip6->ip6_hlim = opt->ip6po_hlim & 0xff; 587 } else { 588 /* Multicast */ 589 struct in6_multi *in6m; 590 591 m->m_flags = (m->m_flags & ~M_BCAST) | M_MCAST; 592 593 /* 594 * See if the caller provided any multicast options 595 */ 596 ifp = NULL; 597 if (im6o != NULL) { 598 ip6->ip6_hlim = im6o->im6o_multicast_hlim; 599 if (im6o->im6o_multicast_ifp != NULL) 600 ifp = im6o->im6o_multicast_ifp; 601 } else 602 ip6->ip6_hlim = ip6_defmcasthlim; 603 604 /* 605 * See if the caller provided the outgoing interface 606 * as an ancillary data. 607 * Boundary check for ifindex is assumed to be already done. 608 */ 609 if (opt && opt->ip6po_pktinfo && opt->ip6po_pktinfo->ipi6_ifindex) 610 ifp = ifindex2ifnet[opt->ip6po_pktinfo->ipi6_ifindex]; 611 612 /* 613 * If the destination is a node-local scope multicast, 614 * the packet should be loop-backed only. 615 */ 616 if (IN6_IS_ADDR_MC_NODELOCAL(&ip6->ip6_dst)) { 617 /* 618 * If the outgoing interface is already specified, 619 * it should be a loopback interface. 620 */ 621 if (ifp && (ifp->if_flags & IFF_LOOPBACK) == 0) { 622 ip6stat.ip6s_badscope++; 623 error = ENETUNREACH; /* XXX: better error? */ 624 /* XXX correct ifp? */ 625 in6_ifstat_inc(ifp, ifs6_out_discard); 626 goto bad; 627 } else { 628 ifp = &loif[0]; 629 } 630 } 631 632 if (opt && opt->ip6po_hlim != -1) 633 ip6->ip6_hlim = opt->ip6po_hlim & 0xff; 634 635 /* 636 * If caller did not provide an interface lookup a 637 * default in the routing table. This is either a 638 * default for the speicfied group (i.e. a host 639 * route), or a multicast default (a route for the 640 * ``net'' ff00::/8). 641 */ 642 if (ifp == NULL) { 643 if (ro->ro_rt == 0) { 644 ro->ro_rt = rtalloc1((struct sockaddr *) 645 &ro->ro_dst, 0); 646 } 647 if (ro->ro_rt == 0) { 648 ip6stat.ip6s_noroute++; 649 error = EHOSTUNREACH; 650 /* XXX in6_ifstat_inc(ifp, ifs6_out_discard) */ 651 goto bad; 652 } 653 ifp = ro->ro_rt->rt_ifp; 654 ro->ro_rt->rt_use++; 655 } 656 657 if ((flags & IPV6_FORWARDING) == 0) 658 in6_ifstat_inc(ifp, ifs6_out_request); 659 in6_ifstat_inc(ifp, ifs6_out_mcast); 660 661 /* 662 * Confirm that the outgoing interface supports multicast. 663 */ 664 if ((ifp->if_flags & IFF_MULTICAST) == 0) { 665 ip6stat.ip6s_noroute++; 666 in6_ifstat_inc(ifp, ifs6_out_discard); 667 error = ENETUNREACH; 668 goto bad; 669 } 670 IN6_LOOKUP_MULTI(ip6->ip6_dst, ifp, in6m); 671 if (in6m != NULL && 672 (im6o == NULL || im6o->im6o_multicast_loop)) { 673 /* 674 * If we belong to the destination multicast group 675 * on the outgoing interface, and the caller did not 676 * forbid loopback, loop back a copy. 677 */ 678 ip6_mloopback(ifp, m, dst); 679 } else { 680 /* 681 * If we are acting as a multicast router, perform 682 * multicast forwarding as if the packet had just 683 * arrived on the interface to which we are about 684 * to send. The multicast forwarding function 685 * recursively calls this function, using the 686 * IPV6_FORWARDING flag to prevent infinite recursion. 687 * 688 * Multicasts that are looped back by ip6_mloopback(), 689 * above, will be forwarded by the ip6_input() routine, 690 * if necessary. 691 */ 692 if (ip6_mrouter && (flags & IPV6_FORWARDING) == 0) { 693 if (ip6_mforward(ip6, ifp, m) != 0) { 694 m_freem(m); 695 goto done; 696 } 697 } 698 } 699 /* 700 * Multicasts with a hoplimit of zero may be looped back, 701 * above, but must not be transmitted on a network. 702 * Also, multicasts addressed to the loopback interface 703 * are not sent -- the above call to ip6_mloopback() will 704 * loop back a copy if this host actually belongs to the 705 * destination group on the loopback interface. 706 */ 707 if (ip6->ip6_hlim == 0 || (ifp->if_flags & IFF_LOOPBACK)) { 708 m_freem(m); 709 goto done; 710 } 711 } 712 713 /* 714 * Fill the outgoing inteface to tell the upper layer 715 * to increment per-interface statistics. 716 */ 717 if (ifpp) 718 *ifpp = ifp; 719 720 /* Determine path MTU. */ 721 if ((error = ip6_getpmtu(ro_pmtu, ro, ifp, &finaldst, &mtu, 722 &alwaysfrag)) != 0) 723 goto bad; 724 #ifdef IPSEC 725 if (needipsectun) 726 mtu = IPV6_MMTU; 727 #endif 728 729 /* 730 * The caller of this function may specify to use the minimum MTU 731 * in some cases. 732 */ 733 if (mtu > IPV6_MMTU) { 734 if ((flags & IPV6_MINMTU)) 735 mtu = IPV6_MMTU; 736 } 737 738 /* Fake scoped addresses */ 739 if ((ifp->if_flags & IFF_LOOPBACK) != 0) { 740 /* 741 * If source or destination address is a scoped address, and 742 * the packet is going to be sent to a loopback interface, 743 * we should keep the original interface. 744 */ 745 746 /* 747 * XXX: this is a very experimental and temporary solution. 748 * We eventually have sockaddr_in6 and use the sin6_scope_id 749 * field of the structure here. 750 * We rely on the consistency between two scope zone ids 751 * of source add destination, which should already be assured 752 * Larger scopes than link will be supported in the near 753 * future. 754 */ 755 origifp = NULL; 756 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) 757 origifp = ifindex2ifnet[ntohs(ip6->ip6_src.s6_addr16[1])]; 758 else if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) 759 origifp = ifindex2ifnet[ntohs(ip6->ip6_dst.s6_addr16[1])]; 760 /* 761 * XXX: origifp can be NULL even in those two cases above. 762 * For example, if we remove the (only) link-local address 763 * from the loopback interface, and try to send a link-local 764 * address without link-id information. Then the source 765 * address is ::1, and the destination address is the 766 * link-local address with its s6_addr16[1] being zero. 767 * What is worse, if the packet goes to the loopback interface 768 * by a default rejected route, the null pointer would be 769 * passed to looutput, and the kernel would hang. 770 * The following last resort would prevent such disaster. 771 */ 772 if (origifp == NULL) 773 origifp = ifp; 774 } else 775 origifp = ifp; 776 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) 777 ip6->ip6_src.s6_addr16[1] = 0; 778 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) 779 ip6->ip6_dst.s6_addr16[1] = 0; 780 781 /* 782 * If the outgoing packet contains a hop-by-hop options header, 783 * it must be examined and processed even by the source node. 784 * (RFC 2460, section 4.) 785 */ 786 if (exthdrs.ip6e_hbh) { 787 struct ip6_hbh *hbh = mtod(exthdrs.ip6e_hbh, struct ip6_hbh *); 788 u_int32_t dummy1; /* XXX unused */ 789 u_int32_t dummy2; /* XXX unused */ 790 791 /* 792 * XXX: if we have to send an ICMPv6 error to the sender, 793 * we need the M_LOOP flag since icmp6_error() expects 794 * the IPv6 and the hop-by-hop options header are 795 * continuous unless the flag is set. 796 */ 797 m->m_flags |= M_LOOP; 798 m->m_pkthdr.rcvif = ifp; 799 if (ip6_process_hopopts(m, (u_int8_t *)(hbh + 1), 800 ((hbh->ip6h_len + 1) << 3) - sizeof(struct ip6_hbh), 801 &dummy1, &dummy2) < 0) { 802 /* m was already freed at this point */ 803 error = EINVAL;/* better error? */ 804 goto done; 805 } 806 m->m_flags &= ~M_LOOP; /* XXX */ 807 m->m_pkthdr.rcvif = NULL; 808 } 809 810 #ifdef PFIL_HOOKS 811 /* 812 * Run through list of hooks for output packets. 813 */ 814 if ((error = pfil_run_hooks(&inet6_pfil_hook, &m, ifp, PFIL_OUT)) != 0) 815 goto done; 816 if (m == NULL) 817 goto done; 818 ip6 = mtod(m, struct ip6_hdr *); 819 #endif /* PFIL_HOOKS */ 820 /* 821 * Send the packet to the outgoing interface. 822 * If necessary, do IPv6 fragmentation before sending. 823 * 824 * the logic here is rather complex: 825 * 1: normal case (dontfrag == 0, alwaysfrag == 0) 826 * 1-a: send as is if tlen <= path mtu 827 * 1-b: fragment if tlen > path mtu 828 * 829 * 2: if user asks us not to fragment (dontfrag == 1) 830 * 2-a: send as is if tlen <= interface mtu 831 * 2-b: error if tlen > interface mtu 832 * 833 * 3: if we always need to attach fragment header (alwaysfrag == 1) 834 * always fragment 835 * 836 * 4: if dontfrag == 1 && alwaysfrag == 1 837 * error, as we cannot handle this conflicting request 838 */ 839 tlen = m->m_pkthdr.len; 840 841 dontfrag = 0; 842 if (dontfrag && alwaysfrag) { /* case 4 */ 843 /* conflicting request - can't transmit */ 844 error = EMSGSIZE; 845 goto bad; 846 } 847 if (dontfrag && tlen > IN6_LINKMTU(ifp)) { /* case 2-b */ 848 /* 849 * Even if the DONTFRAG option is specified, we cannot send the 850 * packet when the data length is larger than the MTU of the 851 * outgoing interface. 852 * Notify the error by sending IPV6_PATHMTU ancillary data as 853 * well as returning an error code (the latter is not described 854 * in the API spec.) 855 */ 856 u_int32_t mtu32; 857 struct ip6ctlparam ip6cp; 858 859 mtu32 = (u_int32_t)mtu; 860 bzero(&ip6cp, sizeof(ip6cp)); 861 ip6cp.ip6c_cmdarg = (void *)&mtu32; 862 pfctlinput2(PRC_MSGSIZE, (struct sockaddr *)&ro_pmtu->ro_dst, 863 (void *)&ip6cp); 864 865 error = EMSGSIZE; 866 goto bad; 867 } 868 869 /* 870 * transmit packet without fragmentation 871 */ 872 if (dontfrag || (!alwaysfrag && tlen <= mtu)) { /* case 1-a and 2-a */ 873 struct in6_ifaddr *ia6; 874 875 ip6 = mtod(m, struct ip6_hdr *); 876 ia6 = in6_ifawithifp(ifp, &ip6->ip6_src); 877 if (ia6) { 878 /* Record statistics for this interface address. */ 879 ia6->ia_ifa.ifa_data.ifad_outbytes += m->m_pkthdr.len; 880 } 881 #ifdef IPSEC 882 /* clean ipsec history once it goes out of the node */ 883 ipsec_delaux(m); 884 #endif 885 error = nd6_output(ifp, origifp, m, dst, ro->ro_rt); 886 goto done; 887 } 888 889 /* 890 * try to fragment the packet. case 1-b and 3 891 */ 892 if (mtu < IPV6_MMTU) { 893 /* path MTU cannot be less than IPV6_MMTU */ 894 error = EMSGSIZE; 895 in6_ifstat_inc(ifp, ifs6_out_fragfail); 896 goto bad; 897 } else if (ip6->ip6_plen == 0) { 898 /* jumbo payload cannot be fragmented */ 899 error = EMSGSIZE; 900 in6_ifstat_inc(ifp, ifs6_out_fragfail); 901 goto bad; 902 } else { 903 struct mbuf **mnext, *m_frgpart; 904 struct ip6_frag *ip6f; 905 u_int32_t id = htonl(ip6_randomid()); 906 u_char nextproto; 907 struct ip6ctlparam ip6cp; 908 u_int32_t mtu32; 909 910 /* 911 * Too large for the destination or interface; 912 * fragment if possible. 913 * Must be able to put at least 8 bytes per fragment. 914 */ 915 hlen = unfragpartlen; 916 if (mtu > IPV6_MAXPACKET) 917 mtu = IPV6_MAXPACKET; 918 919 /* Notify a proper path MTU to applications. */ 920 mtu32 = (u_int32_t)mtu; 921 bzero(&ip6cp, sizeof(ip6cp)); 922 ip6cp.ip6c_cmdarg = (void *)&mtu32; 923 pfctlinput2(PRC_MSGSIZE, (struct sockaddr *)&ro_pmtu->ro_dst, 924 (void *)&ip6cp); 925 926 len = (mtu - hlen - sizeof(struct ip6_frag)) & ~7; 927 if (len < 8) { 928 error = EMSGSIZE; 929 in6_ifstat_inc(ifp, ifs6_out_fragfail); 930 goto bad; 931 } 932 933 mnext = &m->m_nextpkt; 934 935 /* 936 * Change the next header field of the last header in the 937 * unfragmentable part. 938 */ 939 if (exthdrs.ip6e_rthdr) { 940 nextproto = *mtod(exthdrs.ip6e_rthdr, u_char *); 941 *mtod(exthdrs.ip6e_rthdr, u_char *) = IPPROTO_FRAGMENT; 942 } else if (exthdrs.ip6e_dest1) { 943 nextproto = *mtod(exthdrs.ip6e_dest1, u_char *); 944 *mtod(exthdrs.ip6e_dest1, u_char *) = IPPROTO_FRAGMENT; 945 } else if (exthdrs.ip6e_hbh) { 946 nextproto = *mtod(exthdrs.ip6e_hbh, u_char *); 947 *mtod(exthdrs.ip6e_hbh, u_char *) = IPPROTO_FRAGMENT; 948 } else { 949 nextproto = ip6->ip6_nxt; 950 ip6->ip6_nxt = IPPROTO_FRAGMENT; 951 } 952 953 /* 954 * Loop through length of segment after first fragment, 955 * make new header and copy data of each part and link onto 956 * chain. 957 */ 958 m0 = m; 959 for (off = hlen; off < tlen; off += len) { 960 struct mbuf *mlast; 961 962 MGETHDR(m, M_DONTWAIT, MT_HEADER); 963 if (!m) { 964 error = ENOBUFS; 965 ip6stat.ip6s_odropped++; 966 goto sendorfree; 967 } 968 m->m_pkthdr.rcvif = NULL; 969 m->m_flags = m0->m_flags & M_COPYFLAGS; 970 *mnext = m; 971 mnext = &m->m_nextpkt; 972 m->m_data += max_linkhdr; 973 mhip6 = mtod(m, struct ip6_hdr *); 974 *mhip6 = *ip6; 975 m->m_len = sizeof(*mhip6); 976 error = ip6_insertfraghdr(m0, m, hlen, &ip6f); 977 if (error) { 978 ip6stat.ip6s_odropped++; 979 goto sendorfree; 980 } 981 ip6f->ip6f_offlg = htons((u_int16_t)((off - hlen) & ~7)); 982 if (off + len >= tlen) 983 len = tlen - off; 984 else 985 ip6f->ip6f_offlg |= IP6F_MORE_FRAG; 986 mhip6->ip6_plen = htons((u_int16_t)(len + hlen + 987 sizeof(*ip6f) - sizeof(struct ip6_hdr))); 988 if ((m_frgpart = m_copy(m0, off, len)) == 0) { 989 error = ENOBUFS; 990 ip6stat.ip6s_odropped++; 991 goto sendorfree; 992 } 993 for (mlast = m; mlast->m_next; mlast = mlast->m_next) 994 ; 995 mlast->m_next = m_frgpart; 996 m->m_pkthdr.len = len + hlen + sizeof(*ip6f); 997 m->m_pkthdr.rcvif = (struct ifnet *)0; 998 ip6f->ip6f_reserved = 0; 999 ip6f->ip6f_ident = id; 1000 ip6f->ip6f_nxt = nextproto; 1001 ip6stat.ip6s_ofragments++; 1002 in6_ifstat_inc(ifp, ifs6_out_fragcreat); 1003 } 1004 1005 in6_ifstat_inc(ifp, ifs6_out_fragok); 1006 } 1007 1008 /* 1009 * Remove leading garbages. 1010 */ 1011 sendorfree: 1012 m = m0->m_nextpkt; 1013 m0->m_nextpkt = 0; 1014 m_freem(m0); 1015 for (m0 = m; m; m = m0) { 1016 m0 = m->m_nextpkt; 1017 m->m_nextpkt = 0; 1018 if (error == 0) { 1019 struct in6_ifaddr *ia6; 1020 ip6 = mtod(m, struct ip6_hdr *); 1021 ia6 = in6_ifawithifp(ifp, &ip6->ip6_src); 1022 if (ia6) { 1023 /* 1024 * Record statistics for this interface 1025 * address. 1026 */ 1027 ia6->ia_ifa.ifa_data.ifad_outbytes += 1028 m->m_pkthdr.len; 1029 } 1030 #ifdef IPSEC 1031 /* clean ipsec history once it goes out of the node */ 1032 ipsec_delaux(m); 1033 #endif 1034 error = nd6_output(ifp, origifp, m, dst, ro->ro_rt); 1035 } else 1036 m_freem(m); 1037 } 1038 1039 if (error == 0) 1040 ip6stat.ip6s_fragmented++; 1041 1042 done: 1043 if (ro == &ip6route && ro->ro_rt) { /* brace necessary for RTFREE */ 1044 RTFREE(ro->ro_rt); 1045 } else if (ro_pmtu == &ip6route && ro_pmtu->ro_rt) { 1046 RTFREE(ro_pmtu->ro_rt); 1047 } 1048 1049 #ifdef IPSEC 1050 if (sp != NULL) 1051 key_freesp(sp); 1052 #endif /* IPSEC */ 1053 1054 return (error); 1055 1056 freehdrs: 1057 m_freem(exthdrs.ip6e_hbh); /* m_freem will check if mbuf is 0 */ 1058 m_freem(exthdrs.ip6e_dest1); 1059 m_freem(exthdrs.ip6e_rthdr); 1060 m_freem(exthdrs.ip6e_dest2); 1061 /* FALLTHROUGH */ 1062 bad: 1063 m_freem(m); 1064 goto done; 1065 } 1066 1067 static int 1068 ip6_copyexthdr(mp, hdr, hlen) 1069 struct mbuf **mp; 1070 caddr_t hdr; 1071 int hlen; 1072 { 1073 struct mbuf *m; 1074 1075 if (hlen > MCLBYTES) 1076 return (ENOBUFS); /* XXX */ 1077 1078 MGET(m, M_DONTWAIT, MT_DATA); 1079 if (!m) 1080 return (ENOBUFS); 1081 1082 if (hlen > MLEN) { 1083 MCLGET(m, M_DONTWAIT); 1084 if ((m->m_flags & M_EXT) == 0) { 1085 m_free(m); 1086 return (ENOBUFS); 1087 } 1088 } 1089 m->m_len = hlen; 1090 if (hdr) 1091 bcopy(hdr, mtod(m, caddr_t), hlen); 1092 1093 *mp = m; 1094 return (0); 1095 } 1096 1097 /* 1098 * Insert jumbo payload option. 1099 */ 1100 static int 1101 ip6_insert_jumboopt(exthdrs, plen) 1102 struct ip6_exthdrs *exthdrs; 1103 u_int32_t plen; 1104 { 1105 struct mbuf *mopt; 1106 u_int8_t *optbuf; 1107 u_int32_t v; 1108 1109 #define JUMBOOPTLEN 8 /* length of jumbo payload option and padding */ 1110 1111 /* 1112 * If there is no hop-by-hop options header, allocate new one. 1113 * If there is one but it doesn't have enough space to store the 1114 * jumbo payload option, allocate a cluster to store the whole options. 1115 * Otherwise, use it to store the options. 1116 */ 1117 if (exthdrs->ip6e_hbh == 0) { 1118 MGET(mopt, M_DONTWAIT, MT_DATA); 1119 if (mopt == 0) 1120 return (ENOBUFS); 1121 mopt->m_len = JUMBOOPTLEN; 1122 optbuf = mtod(mopt, u_int8_t *); 1123 optbuf[1] = 0; /* = ((JUMBOOPTLEN) >> 3) - 1 */ 1124 exthdrs->ip6e_hbh = mopt; 1125 } else { 1126 struct ip6_hbh *hbh; 1127 1128 mopt = exthdrs->ip6e_hbh; 1129 if (M_TRAILINGSPACE(mopt) < JUMBOOPTLEN) { 1130 /* 1131 * XXX assumption: 1132 * - exthdrs->ip6e_hbh is not referenced from places 1133 * other than exthdrs. 1134 * - exthdrs->ip6e_hbh is not an mbuf chain. 1135 */ 1136 int oldoptlen = mopt->m_len; 1137 struct mbuf *n; 1138 1139 /* 1140 * XXX: give up if the whole (new) hbh header does 1141 * not fit even in an mbuf cluster. 1142 */ 1143 if (oldoptlen + JUMBOOPTLEN > MCLBYTES) 1144 return (ENOBUFS); 1145 1146 /* 1147 * As a consequence, we must always prepare a cluster 1148 * at this point. 1149 */ 1150 MGET(n, M_DONTWAIT, MT_DATA); 1151 if (n) { 1152 MCLGET(n, M_DONTWAIT); 1153 if ((n->m_flags & M_EXT) == 0) { 1154 m_freem(n); 1155 n = NULL; 1156 } 1157 } 1158 if (!n) 1159 return (ENOBUFS); 1160 n->m_len = oldoptlen + JUMBOOPTLEN; 1161 bcopy(mtod(mopt, caddr_t), mtod(n, caddr_t), 1162 oldoptlen); 1163 optbuf = mtod(n, u_int8_t *) + oldoptlen; 1164 m_freem(mopt); 1165 mopt = exthdrs->ip6e_hbh = n; 1166 } else { 1167 optbuf = mtod(mopt, u_int8_t *) + mopt->m_len; 1168 mopt->m_len += JUMBOOPTLEN; 1169 } 1170 optbuf[0] = IP6OPT_PADN; 1171 optbuf[1] = 0; 1172 1173 /* 1174 * Adjust the header length according to the pad and 1175 * the jumbo payload option. 1176 */ 1177 hbh = mtod(mopt, struct ip6_hbh *); 1178 hbh->ip6h_len += (JUMBOOPTLEN >> 3); 1179 } 1180 1181 /* fill in the option. */ 1182 optbuf[2] = IP6OPT_JUMBO; 1183 optbuf[3] = 4; 1184 v = (u_int32_t)htonl(plen + JUMBOOPTLEN); 1185 bcopy(&v, &optbuf[4], sizeof(u_int32_t)); 1186 1187 /* finally, adjust the packet header length */ 1188 exthdrs->ip6e_ip6->m_pkthdr.len += JUMBOOPTLEN; 1189 1190 return (0); 1191 #undef JUMBOOPTLEN 1192 } 1193 1194 /* 1195 * Insert fragment header and copy unfragmentable header portions. 1196 */ 1197 static int 1198 ip6_insertfraghdr(m0, m, hlen, frghdrp) 1199 struct mbuf *m0, *m; 1200 int hlen; 1201 struct ip6_frag **frghdrp; 1202 { 1203 struct mbuf *n, *mlast; 1204 1205 if (hlen > sizeof(struct ip6_hdr)) { 1206 n = m_copym(m0, sizeof(struct ip6_hdr), 1207 hlen - sizeof(struct ip6_hdr), M_DONTWAIT); 1208 if (n == 0) 1209 return (ENOBUFS); 1210 m->m_next = n; 1211 } else 1212 n = m; 1213 1214 /* Search for the last mbuf of unfragmentable part. */ 1215 for (mlast = n; mlast->m_next; mlast = mlast->m_next) 1216 ; 1217 1218 if ((mlast->m_flags & M_EXT) == 0 && 1219 M_TRAILINGSPACE(mlast) >= sizeof(struct ip6_frag)) { 1220 /* use the trailing space of the last mbuf for the fragment hdr */ 1221 *frghdrp = (struct ip6_frag *)(mtod(mlast, caddr_t) + 1222 mlast->m_len); 1223 mlast->m_len += sizeof(struct ip6_frag); 1224 m->m_pkthdr.len += sizeof(struct ip6_frag); 1225 } else { 1226 /* allocate a new mbuf for the fragment header */ 1227 struct mbuf *mfrg; 1228 1229 MGET(mfrg, M_DONTWAIT, MT_DATA); 1230 if (mfrg == 0) 1231 return (ENOBUFS); 1232 mfrg->m_len = sizeof(struct ip6_frag); 1233 *frghdrp = mtod(mfrg, struct ip6_frag *); 1234 mlast->m_next = mfrg; 1235 } 1236 1237 return (0); 1238 } 1239 1240 int 1241 ip6_getpmtu(ro_pmtu, ro, ifp, dst, mtup, alwaysfragp) 1242 struct route_in6 *ro_pmtu, *ro; 1243 struct ifnet *ifp; 1244 struct in6_addr *dst; 1245 u_long *mtup; 1246 int *alwaysfragp; 1247 { 1248 u_int32_t mtu = 0; 1249 int alwaysfrag = 0; 1250 int error = 0; 1251 1252 if (ro_pmtu != ro) { 1253 /* The first hop and the final destination may differ. */ 1254 struct sockaddr_in6 *sa6_dst = 1255 (struct sockaddr_in6 *)&ro_pmtu->ro_dst; 1256 if (ro_pmtu->ro_rt && 1257 ((ro_pmtu->ro_rt->rt_flags & RTF_UP) == 0 || 1258 !IN6_ARE_ADDR_EQUAL(&sa6_dst->sin6_addr, dst))) { 1259 RTFREE(ro_pmtu->ro_rt); 1260 ro_pmtu->ro_rt = (struct rtentry *)NULL; 1261 } 1262 if (ro_pmtu->ro_rt == NULL) { 1263 bzero(sa6_dst, sizeof(*sa6_dst)); /* for safety */ 1264 sa6_dst->sin6_family = AF_INET6; 1265 sa6_dst->sin6_len = sizeof(struct sockaddr_in6); 1266 sa6_dst->sin6_addr = *dst; 1267 1268 rtalloc((struct route *)ro_pmtu); 1269 } 1270 } 1271 if (ro_pmtu->ro_rt) { 1272 u_int32_t ifmtu; 1273 1274 if (ifp == NULL) 1275 ifp = ro_pmtu->ro_rt->rt_ifp; 1276 ifmtu = IN6_LINKMTU(ifp); 1277 mtu = ro_pmtu->ro_rt->rt_rmx.rmx_mtu; 1278 if (mtu == 0) 1279 mtu = ifmtu; 1280 else if (mtu < IPV6_MMTU) { 1281 /* 1282 * RFC2460 section 5, last paragraph: 1283 * if we record ICMPv6 too big message with 1284 * mtu < IPV6_MMTU, transmit packets sized IPV6_MMTU 1285 * or smaller, with fragment header attached. 1286 * (fragment header is needed regardless from the 1287 * packet size, for translators to identify packets) 1288 */ 1289 alwaysfrag = 1; 1290 mtu = IPV6_MMTU; 1291 } else if (mtu > ifmtu) { 1292 /* 1293 * The MTU on the route is larger than the MTU on 1294 * the interface! This shouldn't happen, unless the 1295 * MTU of the interface has been changed after the 1296 * interface was brought up. Change the MTU in the 1297 * route to match the interface MTU (as long as the 1298 * field isn't locked). 1299 */ 1300 mtu = ifmtu; 1301 if (!(ro_pmtu->ro_rt->rt_rmx.rmx_locks & RTV_MTU)) 1302 ro_pmtu->ro_rt->rt_rmx.rmx_mtu = mtu; 1303 } 1304 } else if (ifp) { 1305 mtu = IN6_LINKMTU(ifp); 1306 } else 1307 error = EHOSTUNREACH; /* XXX */ 1308 1309 *mtup = mtu; 1310 if (alwaysfragp) 1311 *alwaysfragp = alwaysfrag; 1312 return (error); 1313 } 1314 1315 /* 1316 * IP6 socket option processing. 1317 */ 1318 int 1319 ip6_ctloutput(op, so, level, optname, mp) 1320 int op; 1321 struct socket *so; 1322 int level, optname; 1323 struct mbuf **mp; 1324 { 1325 struct in6pcb *in6p = sotoin6pcb(so); 1326 struct mbuf *m = *mp; 1327 int optval = 0; 1328 int error = 0; 1329 struct proc *p = curproc; /* XXX */ 1330 1331 if (level == IPPROTO_IPV6) { 1332 switch (op) { 1333 case PRCO_SETOPT: 1334 switch (optname) { 1335 case IPV6_PKTOPTIONS: 1336 /* m is freed in ip6_pcbopts */ 1337 return (ip6_pcbopts(&in6p->in6p_outputopts, 1338 m, so)); 1339 case IPV6_HOPOPTS: 1340 case IPV6_DSTOPTS: 1341 if (p == 0 || suser(p->p_ucred, &p->p_acflag)) { 1342 error = EPERM; 1343 break; 1344 } 1345 /* FALLTHROUGH */ 1346 case IPV6_UNICAST_HOPS: 1347 case IPV6_RECVOPTS: 1348 case IPV6_RECVRETOPTS: 1349 case IPV6_RECVDSTADDR: 1350 case IPV6_PKTINFO: 1351 case IPV6_HOPLIMIT: 1352 case IPV6_RTHDR: 1353 case IPV6_FAITH: 1354 case IPV6_V6ONLY: 1355 case IPV6_USE_MIN_MTU: 1356 if (!m || m->m_len != sizeof(int)) { 1357 error = EINVAL; 1358 break; 1359 } 1360 optval = *mtod(m, int *); 1361 switch (optname) { 1362 1363 case IPV6_UNICAST_HOPS: 1364 if (optval < -1 || optval >= 256) 1365 error = EINVAL; 1366 else { 1367 /* -1 = kernel default */ 1368 in6p->in6p_hops = optval; 1369 } 1370 break; 1371 #define OPTSET(bit) \ 1372 do { \ 1373 if (optval) \ 1374 in6p->in6p_flags |= (bit); \ 1375 else \ 1376 in6p->in6p_flags &= ~(bit); \ 1377 } while (/*CONSTCOND*/ 0) 1378 1379 case IPV6_RECVOPTS: 1380 OPTSET(IN6P_RECVOPTS); 1381 break; 1382 1383 case IPV6_RECVRETOPTS: 1384 OPTSET(IN6P_RECVRETOPTS); 1385 break; 1386 1387 case IPV6_RECVDSTADDR: 1388 OPTSET(IN6P_RECVDSTADDR); 1389 break; 1390 1391 case IPV6_PKTINFO: 1392 OPTSET(IN6P_PKTINFO); 1393 break; 1394 1395 case IPV6_HOPLIMIT: 1396 OPTSET(IN6P_HOPLIMIT); 1397 break; 1398 1399 case IPV6_HOPOPTS: 1400 OPTSET(IN6P_HOPOPTS); 1401 break; 1402 1403 case IPV6_DSTOPTS: 1404 OPTSET(IN6P_DSTOPTS); 1405 break; 1406 1407 case IPV6_RTHDR: 1408 OPTSET(IN6P_RTHDR); 1409 break; 1410 1411 case IPV6_FAITH: 1412 OPTSET(IN6P_FAITH); 1413 break; 1414 1415 case IPV6_USE_MIN_MTU: 1416 OPTSET(IN6P_MINMTU); 1417 break; 1418 1419 case IPV6_V6ONLY: 1420 /* 1421 * make setsockopt(IPV6_V6ONLY) 1422 * available only prior to bind(2). 1423 * see ipng mailing list, Jun 22 2001. 1424 */ 1425 if (in6p->in6p_lport || 1426 !IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr)) { 1427 error = EINVAL; 1428 break; 1429 } 1430 #ifdef INET6_BINDV6ONLY 1431 if (!optval) 1432 error = EINVAL; 1433 #else 1434 OPTSET(IN6P_IPV6_V6ONLY); 1435 #endif 1436 break; 1437 } 1438 break; 1439 #undef OPTSET 1440 1441 case IPV6_MULTICAST_IF: 1442 case IPV6_MULTICAST_HOPS: 1443 case IPV6_MULTICAST_LOOP: 1444 case IPV6_JOIN_GROUP: 1445 case IPV6_LEAVE_GROUP: 1446 error = ip6_setmoptions(optname, 1447 &in6p->in6p_moptions, m); 1448 break; 1449 1450 case IPV6_PORTRANGE: 1451 optval = *mtod(m, int *); 1452 1453 switch (optval) { 1454 case IPV6_PORTRANGE_DEFAULT: 1455 in6p->in6p_flags &= ~(IN6P_LOWPORT); 1456 in6p->in6p_flags &= ~(IN6P_HIGHPORT); 1457 break; 1458 1459 case IPV6_PORTRANGE_HIGH: 1460 in6p->in6p_flags &= ~(IN6P_LOWPORT); 1461 in6p->in6p_flags |= IN6P_HIGHPORT; 1462 break; 1463 1464 case IPV6_PORTRANGE_LOW: 1465 in6p->in6p_flags &= ~(IN6P_HIGHPORT); 1466 in6p->in6p_flags |= IN6P_LOWPORT; 1467 break; 1468 1469 default: 1470 error = EINVAL; 1471 break; 1472 } 1473 break; 1474 1475 #ifdef IPSEC 1476 case IPV6_IPSEC_POLICY: 1477 { 1478 caddr_t req = NULL; 1479 size_t len = 0; 1480 1481 int priv = 0; 1482 if (p == 0 || suser(p->p_ucred, &p->p_acflag)) 1483 priv = 0; 1484 else 1485 priv = 1; 1486 if (m) { 1487 req = mtod(m, caddr_t); 1488 len = m->m_len; 1489 } 1490 error = ipsec6_set_policy(in6p, 1491 optname, req, len, priv); 1492 } 1493 break; 1494 #endif /* IPSEC */ 1495 1496 default: 1497 error = ENOPROTOOPT; 1498 break; 1499 } 1500 if (m) 1501 (void)m_free(m); 1502 break; 1503 1504 case PRCO_GETOPT: 1505 switch (optname) { 1506 1507 case IPV6_OPTIONS: 1508 case IPV6_RETOPTS: 1509 error = ENOPROTOOPT; 1510 break; 1511 1512 case IPV6_PKTOPTIONS: 1513 if (in6p->in6p_options) { 1514 *mp = m_copym(in6p->in6p_options, 0, 1515 M_COPYALL, M_WAIT); 1516 } else { 1517 *mp = m_get(M_WAIT, MT_SOOPTS); 1518 (*mp)->m_len = 0; 1519 } 1520 break; 1521 1522 case IPV6_HOPOPTS: 1523 case IPV6_DSTOPTS: 1524 if (p == 0 || suser(p->p_ucred, &p->p_acflag)) { 1525 error = EPERM; 1526 break; 1527 } 1528 /* FALLTHROUGH */ 1529 case IPV6_UNICAST_HOPS: 1530 case IPV6_RECVOPTS: 1531 case IPV6_RECVRETOPTS: 1532 case IPV6_RECVDSTADDR: 1533 case IPV6_PORTRANGE: 1534 case IPV6_PKTINFO: 1535 case IPV6_HOPLIMIT: 1536 case IPV6_RTHDR: 1537 case IPV6_FAITH: 1538 case IPV6_V6ONLY: 1539 case IPV6_USE_MIN_MTU: 1540 *mp = m = m_get(M_WAIT, MT_SOOPTS); 1541 m->m_len = sizeof(int); 1542 switch (optname) { 1543 1544 case IPV6_UNICAST_HOPS: 1545 optval = in6p->in6p_hops; 1546 break; 1547 1548 #define OPTBIT(bit) (in6p->in6p_flags & bit ? 1 : 0) 1549 1550 case IPV6_RECVOPTS: 1551 optval = OPTBIT(IN6P_RECVOPTS); 1552 break; 1553 1554 case IPV6_RECVRETOPTS: 1555 optval = OPTBIT(IN6P_RECVRETOPTS); 1556 break; 1557 1558 case IPV6_RECVDSTADDR: 1559 optval = OPTBIT(IN6P_RECVDSTADDR); 1560 break; 1561 1562 case IPV6_PORTRANGE: 1563 { 1564 int flags; 1565 flags = in6p->in6p_flags; 1566 if (flags & IN6P_HIGHPORT) 1567 optval = IPV6_PORTRANGE_HIGH; 1568 else if (flags & IN6P_LOWPORT) 1569 optval = IPV6_PORTRANGE_LOW; 1570 else 1571 optval = 0; 1572 break; 1573 } 1574 1575 case IPV6_PKTINFO: 1576 optval = OPTBIT(IN6P_PKTINFO); 1577 break; 1578 1579 case IPV6_HOPLIMIT: 1580 optval = OPTBIT(IN6P_HOPLIMIT); 1581 break; 1582 1583 case IPV6_HOPOPTS: 1584 optval = OPTBIT(IN6P_HOPOPTS); 1585 break; 1586 1587 case IPV6_DSTOPTS: 1588 optval = OPTBIT(IN6P_DSTOPTS); 1589 break; 1590 1591 case IPV6_RTHDR: 1592 optval = OPTBIT(IN6P_RTHDR); 1593 break; 1594 1595 case IPV6_FAITH: 1596 optval = OPTBIT(IN6P_FAITH); 1597 break; 1598 1599 case IPV6_V6ONLY: 1600 optval = OPTBIT(IN6P_IPV6_V6ONLY); 1601 break; 1602 1603 case IPV6_USE_MIN_MTU: 1604 optval = OPTBIT(IN6P_MINMTU); 1605 break; 1606 } 1607 *mtod(m, int *) = optval; 1608 break; 1609 1610 case IPV6_MULTICAST_IF: 1611 case IPV6_MULTICAST_HOPS: 1612 case IPV6_MULTICAST_LOOP: 1613 case IPV6_JOIN_GROUP: 1614 case IPV6_LEAVE_GROUP: 1615 error = ip6_getmoptions(optname, in6p->in6p_moptions, mp); 1616 break; 1617 1618 #if 0 /* defined(IPSEC) */ 1619 /* XXX: code broken */ 1620 case IPV6_IPSEC_POLICY: 1621 { 1622 caddr_t req = NULL; 1623 size_t len = 0; 1624 1625 if (m) { 1626 req = mtod(m, caddr_t); 1627 len = m->m_len; 1628 } 1629 error = ipsec6_get_policy(in6p, req, len, mp); 1630 break; 1631 } 1632 #endif /* IPSEC */ 1633 1634 default: 1635 error = ENOPROTOOPT; 1636 break; 1637 } 1638 break; 1639 } 1640 } else { 1641 error = EINVAL; 1642 if (op == PRCO_SETOPT && *mp) 1643 (void)m_free(*mp); 1644 } 1645 return (error); 1646 } 1647 1648 int 1649 ip6_raw_ctloutput(op, so, level, optname, mp) 1650 int op; 1651 struct socket *so; 1652 int level, optname; 1653 struct mbuf **mp; 1654 { 1655 int error = 0, optval, optlen; 1656 const int icmp6off = offsetof(struct icmp6_hdr, icmp6_cksum); 1657 struct in6pcb *in6p = sotoin6pcb(so); 1658 struct mbuf *m = *mp; 1659 1660 optlen = m ? m->m_len : 0; 1661 1662 if (level != IPPROTO_IPV6) { 1663 if (op == PRCO_SETOPT && *mp) 1664 (void)m_free(*mp); 1665 return (EINVAL); 1666 } 1667 1668 switch (optname) { 1669 case IPV6_CHECKSUM: 1670 /* 1671 * For ICMPv6 sockets, no modification allowed for checksum 1672 * offset, permit "no change" values to help existing apps. 1673 * 1674 * XXX 2292bis says: "An attempt to set IPV6_CHECKSUM 1675 * for an ICMPv6 socket will fail." 1676 * The current behavior does not meet 2292bis. 1677 */ 1678 switch (op) { 1679 case PRCO_SETOPT: 1680 if (optlen != sizeof(int)) { 1681 error = EINVAL; 1682 break; 1683 } 1684 optval = *mtod(m, int *); 1685 if ((optval % 2) != 0) { 1686 /* the API assumes even offset values */ 1687 error = EINVAL; 1688 } else if (so->so_proto->pr_protocol == 1689 IPPROTO_ICMPV6) { 1690 if (optval != icmp6off) 1691 error = EINVAL; 1692 } else 1693 in6p->in6p_cksum = optval; 1694 break; 1695 1696 case PRCO_GETOPT: 1697 if (so->so_proto->pr_protocol == IPPROTO_ICMPV6) 1698 optval = icmp6off; 1699 else 1700 optval = in6p->in6p_cksum; 1701 1702 *mp = m = m_get(M_WAIT, MT_SOOPTS); 1703 m->m_len = sizeof(int); 1704 *mtod(m, int *) = optval; 1705 break; 1706 1707 default: 1708 error = EINVAL; 1709 break; 1710 } 1711 break; 1712 1713 default: 1714 error = ENOPROTOOPT; 1715 break; 1716 } 1717 1718 if (op == PRCO_SETOPT && m) 1719 (void)m_free(m); 1720 1721 return (error); 1722 } 1723 1724 /* 1725 * Set up IP6 options in pcb for insertion in output packets. 1726 * Store in mbuf with pointer in pcbopt, adding pseudo-option 1727 * with destination address if source routed. 1728 */ 1729 static int 1730 ip6_pcbopts(pktopt, m, so) 1731 struct ip6_pktopts **pktopt; 1732 struct mbuf *m; 1733 struct socket *so; 1734 { 1735 struct ip6_pktopts *opt = *pktopt; 1736 int error = 0; 1737 struct proc *p = curproc; /* XXX */ 1738 int priv = 0; 1739 1740 /* turn off any old options. */ 1741 if (opt) { 1742 if (opt->ip6po_m) 1743 (void)m_free(opt->ip6po_m); 1744 } else 1745 opt = malloc(sizeof(*opt), M_IP6OPT, M_WAITOK); 1746 *pktopt = 0; 1747 1748 if (!m || m->m_len == 0) { 1749 /* 1750 * Only turning off any previous options. 1751 */ 1752 free(opt, M_IP6OPT); 1753 if (m) 1754 (void)m_free(m); 1755 return (0); 1756 } 1757 1758 /* set options specified by user. */ 1759 if (p && !suser(p->p_ucred, &p->p_acflag)) 1760 priv = 1; 1761 if ((error = ip6_setpktoptions(m, opt, priv)) != 0) { 1762 (void)m_free(m); 1763 free(opt, M_IP6OPT); 1764 return (error); 1765 } 1766 *pktopt = opt; 1767 return (0); 1768 } 1769 1770 /* 1771 * Set the IP6 multicast options in response to user setsockopt(). 1772 */ 1773 static int 1774 ip6_setmoptions(optname, im6op, m) 1775 int optname; 1776 struct ip6_moptions **im6op; 1777 struct mbuf *m; 1778 { 1779 int error = 0; 1780 u_int loop, ifindex; 1781 struct ipv6_mreq *mreq; 1782 struct ifnet *ifp; 1783 struct ip6_moptions *im6o = *im6op; 1784 struct route_in6 ro; 1785 struct sockaddr_in6 *dst; 1786 struct in6_multi_mship *imm; 1787 struct proc *p = curproc; /* XXX */ 1788 1789 if (im6o == NULL) { 1790 /* 1791 * No multicast option buffer attached to the pcb; 1792 * allocate one and initialize to default values. 1793 */ 1794 im6o = (struct ip6_moptions *) 1795 malloc(sizeof(*im6o), M_IPMOPTS, M_WAITOK); 1796 1797 if (im6o == NULL) 1798 return (ENOBUFS); 1799 *im6op = im6o; 1800 im6o->im6o_multicast_ifp = NULL; 1801 im6o->im6o_multicast_hlim = ip6_defmcasthlim; 1802 im6o->im6o_multicast_loop = IPV6_DEFAULT_MULTICAST_LOOP; 1803 LIST_INIT(&im6o->im6o_memberships); 1804 } 1805 1806 switch (optname) { 1807 1808 case IPV6_MULTICAST_IF: 1809 /* 1810 * Select the interface for outgoing multicast packets. 1811 */ 1812 if (m == NULL || m->m_len != sizeof(u_int)) { 1813 error = EINVAL; 1814 break; 1815 } 1816 bcopy(mtod(m, u_int *), &ifindex, sizeof(ifindex)); 1817 if (ifindex < 0 || if_indexlim <= ifindex || 1818 !ifindex2ifnet[ifindex]) { 1819 error = ENXIO; /* XXX EINVAL? */ 1820 break; 1821 } 1822 ifp = ifindex2ifnet[ifindex]; 1823 if (ifp == NULL || (ifp->if_flags & IFF_MULTICAST) == 0) { 1824 error = EADDRNOTAVAIL; 1825 break; 1826 } 1827 im6o->im6o_multicast_ifp = ifp; 1828 break; 1829 1830 case IPV6_MULTICAST_HOPS: 1831 { 1832 /* 1833 * Set the IP6 hoplimit for outgoing multicast packets. 1834 */ 1835 int optval; 1836 if (m == NULL || m->m_len != sizeof(int)) { 1837 error = EINVAL; 1838 break; 1839 } 1840 bcopy(mtod(m, u_int *), &optval, sizeof(optval)); 1841 if (optval < -1 || optval >= 256) 1842 error = EINVAL; 1843 else if (optval == -1) 1844 im6o->im6o_multicast_hlim = ip6_defmcasthlim; 1845 else 1846 im6o->im6o_multicast_hlim = optval; 1847 break; 1848 } 1849 1850 case IPV6_MULTICAST_LOOP: 1851 /* 1852 * Set the loopback flag for outgoing multicast packets. 1853 * Must be zero or one. 1854 */ 1855 if (m == NULL || m->m_len != sizeof(u_int)) { 1856 error = EINVAL; 1857 break; 1858 } 1859 bcopy(mtod(m, u_int *), &loop, sizeof(loop)); 1860 if (loop > 1) { 1861 error = EINVAL; 1862 break; 1863 } 1864 im6o->im6o_multicast_loop = loop; 1865 break; 1866 1867 case IPV6_JOIN_GROUP: 1868 /* 1869 * Add a multicast group membership. 1870 * Group must be a valid IP6 multicast address. 1871 */ 1872 if (m == NULL || m->m_len != sizeof(struct ipv6_mreq)) { 1873 error = EINVAL; 1874 break; 1875 } 1876 mreq = mtod(m, struct ipv6_mreq *); 1877 if (IN6_IS_ADDR_UNSPECIFIED(&mreq->ipv6mr_multiaddr)) { 1878 /* 1879 * We use the unspecified address to specify to accept 1880 * all multicast addresses. Only super user is allowed 1881 * to do this. 1882 */ 1883 if (suser(p->p_ucred, &p->p_acflag)) 1884 { 1885 error = EACCES; 1886 break; 1887 } 1888 } else if (!IN6_IS_ADDR_MULTICAST(&mreq->ipv6mr_multiaddr)) { 1889 error = EINVAL; 1890 break; 1891 } 1892 1893 /* 1894 * If the interface is specified, validate it. 1895 */ 1896 if (mreq->ipv6mr_interface < 0 || 1897 if_indexlim <= mreq->ipv6mr_interface || 1898 !ifindex2ifnet[mreq->ipv6mr_interface]) { 1899 error = ENXIO; /* XXX EINVAL? */ 1900 break; 1901 } 1902 /* 1903 * If no interface was explicitly specified, choose an 1904 * appropriate one according to the given multicast address. 1905 */ 1906 if (mreq->ipv6mr_interface == 0) { 1907 /* 1908 * If the multicast address is in node-local scope, 1909 * the interface should be a loopback interface. 1910 * Otherwise, look up the routing table for the 1911 * address, and choose the outgoing interface. 1912 * XXX: is it a good approach? 1913 */ 1914 if (IN6_IS_ADDR_MC_NODELOCAL(&mreq->ipv6mr_multiaddr)) { 1915 ifp = &loif[0]; 1916 } else { 1917 ro.ro_rt = NULL; 1918 dst = (struct sockaddr_in6 *)&ro.ro_dst; 1919 bzero(dst, sizeof(*dst)); 1920 dst->sin6_len = sizeof(struct sockaddr_in6); 1921 dst->sin6_family = AF_INET6; 1922 dst->sin6_addr = mreq->ipv6mr_multiaddr; 1923 rtalloc((struct route *)&ro); 1924 if (ro.ro_rt == NULL) { 1925 error = EADDRNOTAVAIL; 1926 break; 1927 } 1928 ifp = ro.ro_rt->rt_ifp; 1929 rtfree(ro.ro_rt); 1930 } 1931 } else 1932 ifp = ifindex2ifnet[mreq->ipv6mr_interface]; 1933 1934 /* 1935 * See if we found an interface, and confirm that it 1936 * supports multicast 1937 */ 1938 if (ifp == NULL || (ifp->if_flags & IFF_MULTICAST) == 0) { 1939 error = EADDRNOTAVAIL; 1940 break; 1941 } 1942 /* 1943 * Put interface index into the multicast address, 1944 * if the address has link-local scope. 1945 */ 1946 if (IN6_IS_ADDR_MC_LINKLOCAL(&mreq->ipv6mr_multiaddr)) { 1947 mreq->ipv6mr_multiaddr.s6_addr16[1] = 1948 htons(ifp->if_index); 1949 } 1950 /* 1951 * See if the membership already exists. 1952 */ 1953 for (imm = im6o->im6o_memberships.lh_first; 1954 imm != NULL; imm = imm->i6mm_chain.le_next) 1955 if (imm->i6mm_maddr->in6m_ifp == ifp && 1956 IN6_ARE_ADDR_EQUAL(&imm->i6mm_maddr->in6m_addr, 1957 &mreq->ipv6mr_multiaddr)) 1958 break; 1959 if (imm != NULL) { 1960 error = EADDRINUSE; 1961 break; 1962 } 1963 /* 1964 * Everything looks good; add a new record to the multicast 1965 * address list for the given interface. 1966 */ 1967 imm = in6_joingroup(ifp, &mreq->ipv6mr_multiaddr, &error); 1968 if (!imm) 1969 break; 1970 LIST_INSERT_HEAD(&im6o->im6o_memberships, imm, i6mm_chain); 1971 break; 1972 1973 case IPV6_LEAVE_GROUP: 1974 /* 1975 * Drop a multicast group membership. 1976 * Group must be a valid IP6 multicast address. 1977 */ 1978 if (m == NULL || m->m_len != sizeof(struct ipv6_mreq)) { 1979 error = EINVAL; 1980 break; 1981 } 1982 mreq = mtod(m, struct ipv6_mreq *); 1983 if (IN6_IS_ADDR_UNSPECIFIED(&mreq->ipv6mr_multiaddr)) { 1984 if (suser(p->p_ucred, &p->p_acflag)) 1985 { 1986 error = EACCES; 1987 break; 1988 } 1989 } else if (!IN6_IS_ADDR_MULTICAST(&mreq->ipv6mr_multiaddr)) { 1990 error = EINVAL; 1991 break; 1992 } 1993 /* 1994 * If an interface address was specified, get a pointer 1995 * to its ifnet structure. 1996 */ 1997 if (mreq->ipv6mr_interface < 0 || 1998 if_indexlim <= mreq->ipv6mr_interface || 1999 !ifindex2ifnet[mreq->ipv6mr_interface]) { 2000 error = ENXIO; /* XXX EINVAL? */ 2001 break; 2002 } 2003 ifp = ifindex2ifnet[mreq->ipv6mr_interface]; 2004 /* 2005 * Put interface index into the multicast address, 2006 * if the address has link-local scope. 2007 */ 2008 if (IN6_IS_ADDR_MC_LINKLOCAL(&mreq->ipv6mr_multiaddr)) { 2009 mreq->ipv6mr_multiaddr.s6_addr16[1] = 2010 htons(mreq->ipv6mr_interface); 2011 } 2012 /* 2013 * Find the membership in the membership list. 2014 */ 2015 for (imm = im6o->im6o_memberships.lh_first; 2016 imm != NULL; imm = imm->i6mm_chain.le_next) { 2017 if ((ifp == NULL || imm->i6mm_maddr->in6m_ifp == ifp) && 2018 IN6_ARE_ADDR_EQUAL(&imm->i6mm_maddr->in6m_addr, 2019 &mreq->ipv6mr_multiaddr)) 2020 break; 2021 } 2022 if (imm == NULL) { 2023 /* Unable to resolve interface */ 2024 error = EADDRNOTAVAIL; 2025 break; 2026 } 2027 /* 2028 * Give up the multicast address record to which the 2029 * membership points. 2030 */ 2031 LIST_REMOVE(imm, i6mm_chain); 2032 in6_leavegroup(imm); 2033 break; 2034 2035 default: 2036 error = EOPNOTSUPP; 2037 break; 2038 } 2039 2040 /* 2041 * If all options have default values, no need to keep the mbuf. 2042 */ 2043 if (im6o->im6o_multicast_ifp == NULL && 2044 im6o->im6o_multicast_hlim == ip6_defmcasthlim && 2045 im6o->im6o_multicast_loop == IPV6_DEFAULT_MULTICAST_LOOP && 2046 im6o->im6o_memberships.lh_first == NULL) { 2047 free(*im6op, M_IPMOPTS); 2048 *im6op = NULL; 2049 } 2050 2051 return (error); 2052 } 2053 2054 /* 2055 * Return the IP6 multicast options in response to user getsockopt(). 2056 */ 2057 static int 2058 ip6_getmoptions(optname, im6o, mp) 2059 int optname; 2060 struct ip6_moptions *im6o; 2061 struct mbuf **mp; 2062 { 2063 u_int *hlim, *loop, *ifindex; 2064 2065 *mp = m_get(M_WAIT, MT_SOOPTS); 2066 2067 switch (optname) { 2068 2069 case IPV6_MULTICAST_IF: 2070 ifindex = mtod(*mp, u_int *); 2071 (*mp)->m_len = sizeof(u_int); 2072 if (im6o == NULL || im6o->im6o_multicast_ifp == NULL) 2073 *ifindex = 0; 2074 else 2075 *ifindex = im6o->im6o_multicast_ifp->if_index; 2076 return (0); 2077 2078 case IPV6_MULTICAST_HOPS: 2079 hlim = mtod(*mp, u_int *); 2080 (*mp)->m_len = sizeof(u_int); 2081 if (im6o == NULL) 2082 *hlim = ip6_defmcasthlim; 2083 else 2084 *hlim = im6o->im6o_multicast_hlim; 2085 return (0); 2086 2087 case IPV6_MULTICAST_LOOP: 2088 loop = mtod(*mp, u_int *); 2089 (*mp)->m_len = sizeof(u_int); 2090 if (im6o == NULL) 2091 *loop = ip6_defmcasthlim; 2092 else 2093 *loop = im6o->im6o_multicast_loop; 2094 return (0); 2095 2096 default: 2097 return (EOPNOTSUPP); 2098 } 2099 } 2100 2101 /* 2102 * Discard the IP6 multicast options. 2103 */ 2104 void 2105 ip6_freemoptions(im6o) 2106 struct ip6_moptions *im6o; 2107 { 2108 struct in6_multi_mship *imm; 2109 2110 if (im6o == NULL) 2111 return; 2112 2113 while ((imm = im6o->im6o_memberships.lh_first) != NULL) { 2114 LIST_REMOVE(imm, i6mm_chain); 2115 in6_leavegroup(imm); 2116 } 2117 free(im6o, M_IPMOPTS); 2118 } 2119 2120 /* 2121 * Set IPv6 outgoing packet options based on advanced API. 2122 */ 2123 int 2124 ip6_setpktoptions(control, opt, priv) 2125 struct mbuf *control; 2126 struct ip6_pktopts *opt; 2127 int priv; 2128 { 2129 struct cmsghdr *cm = 0; 2130 2131 if (control == 0 || opt == 0) 2132 return (EINVAL); 2133 2134 bzero(opt, sizeof(*opt)); 2135 opt->ip6po_hlim = -1; /* -1 means to use default hop limit */ 2136 2137 /* 2138 * XXX: Currently, we assume all the optional information is stored 2139 * in a single mbuf. 2140 */ 2141 if (control->m_next) 2142 return (EINVAL); 2143 2144 opt->ip6po_m = control; 2145 2146 for (; control->m_len; control->m_data += CMSG_ALIGN(cm->cmsg_len), 2147 control->m_len -= CMSG_ALIGN(cm->cmsg_len)) { 2148 cm = mtod(control, struct cmsghdr *); 2149 if (cm->cmsg_len == 0 || cm->cmsg_len > control->m_len) 2150 return (EINVAL); 2151 if (cm->cmsg_level != IPPROTO_IPV6) 2152 continue; 2153 2154 switch (cm->cmsg_type) { 2155 case IPV6_PKTINFO: 2156 if (cm->cmsg_len != CMSG_LEN(sizeof(struct in6_pktinfo))) 2157 return (EINVAL); 2158 opt->ip6po_pktinfo = (struct in6_pktinfo *)CMSG_DATA(cm); 2159 if (opt->ip6po_pktinfo->ipi6_ifindex && 2160 IN6_IS_ADDR_LINKLOCAL(&opt->ip6po_pktinfo->ipi6_addr)) 2161 opt->ip6po_pktinfo->ipi6_addr.s6_addr16[1] = 2162 htons(opt->ip6po_pktinfo->ipi6_ifindex); 2163 2164 if (opt->ip6po_pktinfo->ipi6_ifindex >= if_indexlim || 2165 opt->ip6po_pktinfo->ipi6_ifindex < 0) 2166 return (ENXIO); 2167 if (opt->ip6po_pktinfo->ipi6_ifindex > 0 && 2168 !ifindex2ifnet[opt->ip6po_pktinfo->ipi6_ifindex]) 2169 return (ENXIO); 2170 2171 /* 2172 * Check if the requested source address is indeed a 2173 * unicast address assigned to the node, and can be 2174 * used as the packet's source address. 2175 */ 2176 if (!IN6_IS_ADDR_UNSPECIFIED(&opt->ip6po_pktinfo->ipi6_addr)) { 2177 struct ifaddr *ia; 2178 struct in6_ifaddr *ia6; 2179 struct sockaddr_in6 sin6; 2180 2181 bzero(&sin6, sizeof(sin6)); 2182 sin6.sin6_len = sizeof(sin6); 2183 sin6.sin6_family = AF_INET6; 2184 sin6.sin6_addr = 2185 opt->ip6po_pktinfo->ipi6_addr; 2186 ia = ifa_ifwithaddr(sin6tosa(&sin6)); 2187 if (ia == NULL || 2188 (opt->ip6po_pktinfo->ipi6_ifindex && 2189 (ia->ifa_ifp->if_index != 2190 opt->ip6po_pktinfo->ipi6_ifindex))) { 2191 return (EADDRNOTAVAIL); 2192 } 2193 ia6 = (struct in6_ifaddr *)ia; 2194 if ((ia6->ia6_flags & (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY)) != 0) { 2195 return (EADDRNOTAVAIL); 2196 } 2197 2198 /* 2199 * Check if the requested source address is 2200 * indeed a unicast address assigned to the 2201 * node. 2202 */ 2203 if (IN6_IS_ADDR_MULTICAST(&opt->ip6po_pktinfo->ipi6_addr)) 2204 return (EADDRNOTAVAIL); 2205 } 2206 break; 2207 2208 case IPV6_HOPLIMIT: 2209 if (cm->cmsg_len != CMSG_LEN(sizeof(int))) 2210 return (EINVAL); 2211 else { 2212 int t; 2213 2214 bcopy(CMSG_DATA(cm), &t, sizeof(t)); 2215 if (t < -1 || t > 255) 2216 return (EINVAL); 2217 opt->ip6po_hlim = t; 2218 } 2219 break; 2220 2221 case IPV6_NEXTHOP: 2222 if (!priv) 2223 return (EPERM); 2224 2225 /* check if cmsg_len is large enough for sa_len */ 2226 if (cm->cmsg_len < sizeof(u_char) || 2227 cm->cmsg_len < CMSG_LEN(*CMSG_DATA(cm))) 2228 return (EINVAL); 2229 2230 opt->ip6po_nexthop = (struct sockaddr *)CMSG_DATA(cm); 2231 2232 break; 2233 2234 case IPV6_HOPOPTS: 2235 if (cm->cmsg_len < CMSG_LEN(sizeof(struct ip6_hbh))) 2236 return (EINVAL); 2237 else { 2238 struct ip6_hbh *t; 2239 2240 t = (struct ip6_hbh *)CMSG_DATA(cm); 2241 if (cm->cmsg_len != 2242 CMSG_LEN((t->ip6h_len + 1) << 3)) 2243 return (EINVAL); 2244 opt->ip6po_hbh = t; 2245 } 2246 break; 2247 2248 case IPV6_DSTOPTS: 2249 if (cm->cmsg_len < CMSG_LEN(sizeof(struct ip6_dest))) 2250 return (EINVAL); 2251 2252 /* 2253 * If there is no routing header yet, the destination 2254 * options header should be put on the 1st part. 2255 * Otherwise, the header should be on the 2nd part. 2256 * (See RFC 2460, section 4.1) 2257 */ 2258 if (opt->ip6po_rthdr == NULL) { 2259 struct ip6_dest *t; 2260 2261 t = (struct ip6_dest *)CMSG_DATA(cm); 2262 if (cm->cmsg_len != 2263 CMSG_LEN((t->ip6d_len + 1) << 3)); 2264 return (EINVAL); 2265 opt->ip6po_dest1 = t; 2266 } 2267 else { 2268 struct ip6_dest *t; 2269 2270 t = (struct ip6_dest *)CMSG_DATA(cm); 2271 if (cm->cmsg_len != 2272 CMSG_LEN((opt->ip6po_dest2->ip6d_len + 1) << 3)) 2273 return (EINVAL); 2274 opt->ip6po_dest2 = t; 2275 } 2276 break; 2277 2278 case IPV6_RTHDR: 2279 if (cm->cmsg_len < CMSG_LEN(sizeof(struct ip6_rthdr))) 2280 return (EINVAL); 2281 else { 2282 struct ip6_rthdr *t; 2283 2284 t = (struct ip6_rthdr *)CMSG_DATA(cm); 2285 if (cm->cmsg_len != 2286 CMSG_LEN((t->ip6r_len + 1) << 3)) 2287 return (EINVAL); 2288 switch (t->ip6r_type) { 2289 case IPV6_RTHDR_TYPE_0: 2290 if (t->ip6r_segleft == 0) 2291 return (EINVAL); 2292 break; 2293 default: 2294 return (EINVAL); 2295 } 2296 opt->ip6po_rthdr = t; 2297 } 2298 break; 2299 2300 default: 2301 return (ENOPROTOOPT); 2302 } 2303 } 2304 2305 return (0); 2306 } 2307 2308 /* 2309 * Routine called from ip6_output() to loop back a copy of an IP6 multicast 2310 * packet to the input queue of a specified interface. Note that this 2311 * calls the output routine of the loopback "driver", but with an interface 2312 * pointer that might NOT be &loif -- easier than replicating that code here. 2313 */ 2314 void 2315 ip6_mloopback(ifp, m, dst) 2316 struct ifnet *ifp; 2317 struct mbuf *m; 2318 struct sockaddr_in6 *dst; 2319 { 2320 struct mbuf *copym; 2321 struct ip6_hdr *ip6; 2322 2323 copym = m_copy(m, 0, M_COPYALL); 2324 if (copym == NULL) 2325 return; 2326 2327 /* 2328 * Make sure to deep-copy IPv6 header portion in case the data 2329 * is in an mbuf cluster, so that we can safely override the IPv6 2330 * header portion later. 2331 */ 2332 if ((copym->m_flags & M_EXT) != 0 || 2333 copym->m_len < sizeof(struct ip6_hdr)) { 2334 copym = m_pullup(copym, sizeof(struct ip6_hdr)); 2335 if (copym == NULL) 2336 return; 2337 } 2338 2339 #ifdef DIAGNOSTIC 2340 if (copym->m_len < sizeof(*ip6)) { 2341 m_freem(copym); 2342 return; 2343 } 2344 #endif 2345 2346 ip6 = mtod(copym, struct ip6_hdr *); 2347 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) 2348 ip6->ip6_src.s6_addr16[1] = 0; 2349 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) 2350 ip6->ip6_dst.s6_addr16[1] = 0; 2351 2352 (void)looutput(ifp, copym, (struct sockaddr *)dst, NULL); 2353 } 2354 2355 /* 2356 * Chop IPv6 header off from the payload. 2357 */ 2358 static int 2359 ip6_splithdr(m, exthdrs) 2360 struct mbuf *m; 2361 struct ip6_exthdrs *exthdrs; 2362 { 2363 struct mbuf *mh; 2364 struct ip6_hdr *ip6; 2365 2366 ip6 = mtod(m, struct ip6_hdr *); 2367 if (m->m_len > sizeof(*ip6)) { 2368 MGETHDR(mh, M_DONTWAIT, MT_HEADER); 2369 if (mh == 0) { 2370 m_freem(m); 2371 return ENOBUFS; 2372 } 2373 M_COPY_PKTHDR(mh, m); 2374 MH_ALIGN(mh, sizeof(*ip6)); 2375 m_tag_delete_chain(m, NULL); 2376 m->m_flags &= ~M_PKTHDR; 2377 m->m_len -= sizeof(*ip6); 2378 m->m_data += sizeof(*ip6); 2379 mh->m_next = m; 2380 m = mh; 2381 m->m_len = sizeof(*ip6); 2382 bcopy((caddr_t)ip6, mtod(m, caddr_t), sizeof(*ip6)); 2383 } 2384 exthdrs->ip6e_ip6 = m; 2385 return 0; 2386 } 2387 2388 /* 2389 * Compute IPv6 extension header length. 2390 */ 2391 int 2392 ip6_optlen(in6p) 2393 struct in6pcb *in6p; 2394 { 2395 int len; 2396 2397 if (!in6p->in6p_outputopts) 2398 return 0; 2399 2400 len = 0; 2401 #define elen(x) \ 2402 (((struct ip6_ext *)(x)) ? (((struct ip6_ext *)(x))->ip6e_len + 1) << 3 : 0) 2403 2404 len += elen(in6p->in6p_outputopts->ip6po_hbh); 2405 len += elen(in6p->in6p_outputopts->ip6po_dest1); 2406 len += elen(in6p->in6p_outputopts->ip6po_rthdr); 2407 len += elen(in6p->in6p_outputopts->ip6po_dest2); 2408 return len; 2409 #undef elen 2410 } 2411