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_output.c,v 1.279 2002/01/26 06:12:30 jinmei Exp $ 30 */ 31 32 /*- 33 * Copyright (c) 1982, 1986, 1988, 1990, 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_output.c 8.3 (Berkeley) 1/21/94 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_sctp.h" 71 #include "opt_route.h" 72 73 #include <sys/param.h> 74 #include <sys/kernel.h> 75 #include <sys/malloc.h> 76 #include <sys/mbuf.h> 77 #include <sys/errno.h> 78 #include <sys/priv.h> 79 #include <sys/proc.h> 80 #include <sys/protosw.h> 81 #include <sys/socket.h> 82 #include <sys/socketvar.h> 83 #include <sys/syslog.h> 84 #include <sys/ucred.h> 85 86 #include <machine/in_cksum.h> 87 88 #include <net/if.h> 89 #include <net/if_var.h> 90 #include <net/netisr.h> 91 #include <net/route.h> 92 #include <net/pfil.h> 93 #include <net/vnet.h> 94 95 #include <netinet/in.h> 96 #include <netinet/in_var.h> 97 #include <netinet/ip_var.h> 98 #include <netinet6/in6_var.h> 99 #include <netinet/ip6.h> 100 #include <netinet/icmp6.h> 101 #include <netinet6/ip6_var.h> 102 #include <netinet/in_pcb.h> 103 #include <netinet/tcp_var.h> 104 #include <netinet6/nd6.h> 105 106 #ifdef IPSEC 107 #include <netipsec/ipsec.h> 108 #include <netipsec/ipsec6.h> 109 #include <netipsec/key.h> 110 #include <netinet6/ip6_ipsec.h> 111 #endif /* IPSEC */ 112 #ifdef SCTP 113 #include <netinet/sctp.h> 114 #include <netinet/sctp_crc32.h> 115 #endif 116 117 #include <netinet6/ip6protosw.h> 118 #include <netinet6/scope6_var.h> 119 120 #ifdef FLOWTABLE 121 #include <net/flowtable.h> 122 #endif 123 124 extern int in6_mcast_loop; 125 126 struct ip6_exthdrs { 127 struct mbuf *ip6e_ip6; 128 struct mbuf *ip6e_hbh; 129 struct mbuf *ip6e_dest1; 130 struct mbuf *ip6e_rthdr; 131 struct mbuf *ip6e_dest2; 132 }; 133 134 static int ip6_pcbopt(int, u_char *, int, struct ip6_pktopts **, 135 struct ucred *, int); 136 static int ip6_pcbopts(struct ip6_pktopts **, struct mbuf *, 137 struct socket *, struct sockopt *); 138 static int ip6_getpcbopt(struct ip6_pktopts *, int, struct sockopt *); 139 static int ip6_setpktopt(int, u_char *, int, struct ip6_pktopts *, 140 struct ucred *, int, int, int); 141 142 static int ip6_copyexthdr(struct mbuf **, caddr_t, int); 143 static int ip6_insertfraghdr(struct mbuf *, struct mbuf *, int, 144 struct ip6_frag **); 145 static int ip6_insert_jumboopt(struct ip6_exthdrs *, u_int32_t); 146 static int ip6_splithdr(struct mbuf *, struct ip6_exthdrs *); 147 static int ip6_getpmtu(struct route_in6 *, struct route_in6 *, 148 struct ifnet *, struct in6_addr *, u_long *, int *, u_int); 149 static int copypktopts(struct ip6_pktopts *, struct ip6_pktopts *, int); 150 151 152 /* 153 * Make an extension header from option data. hp is the source, and 154 * mp is the destination. 155 */ 156 #define MAKE_EXTHDR(hp, mp) \ 157 do { \ 158 if (hp) { \ 159 struct ip6_ext *eh = (struct ip6_ext *)(hp); \ 160 error = ip6_copyexthdr((mp), (caddr_t)(hp), \ 161 ((eh)->ip6e_len + 1) << 3); \ 162 if (error) \ 163 goto freehdrs; \ 164 } \ 165 } while (/*CONSTCOND*/ 0) 166 167 /* 168 * Form a chain of extension headers. 169 * m is the extension header mbuf 170 * mp is the previous mbuf in the chain 171 * p is the next header 172 * i is the type of option. 173 */ 174 #define MAKE_CHAIN(m, mp, p, i)\ 175 do {\ 176 if (m) {\ 177 if (!hdrsplit) \ 178 panic("assumption failed: hdr not split"); \ 179 *mtod((m), u_char *) = *(p);\ 180 *(p) = (i);\ 181 p = mtod((m), u_char *);\ 182 (m)->m_next = (mp)->m_next;\ 183 (mp)->m_next = (m);\ 184 (mp) = (m);\ 185 }\ 186 } while (/*CONSTCOND*/ 0) 187 188 void 189 in6_delayed_cksum(struct mbuf *m, uint32_t plen, u_short offset) 190 { 191 u_short csum; 192 193 csum = in_cksum_skip(m, offset + plen, offset); 194 if (m->m_pkthdr.csum_flags & CSUM_UDP_IPV6 && csum == 0) 195 csum = 0xffff; 196 offset += m->m_pkthdr.csum_data; /* checksum offset */ 197 198 if (offset + sizeof(u_short) > m->m_len) { 199 printf("%s: delayed m_pullup, m->len: %d plen %u off %u " 200 "csum_flags=%b\n", __func__, m->m_len, plen, offset, 201 (int)m->m_pkthdr.csum_flags, CSUM_BITS); 202 /* 203 * XXX this should not happen, but if it does, the correct 204 * behavior may be to insert the checksum in the appropriate 205 * next mbuf in the chain. 206 */ 207 return; 208 } 209 *(u_short *)(m->m_data + offset) = csum; 210 } 211 212 /* 213 * IP6 output. The packet in mbuf chain m contains a skeletal IP6 214 * header (with pri, len, nxt, hlim, src, dst). 215 * This function may modify ver and hlim only. 216 * The mbuf chain containing the packet will be freed. 217 * The mbuf opt, if present, will not be freed. 218 * If route_in6 ro is present and has ro_rt initialized, route lookup would be 219 * skipped and ro->ro_rt would be used. If ro is present but ro->ro_rt is NULL, 220 * then result of route lookup is stored in ro->ro_rt. 221 * 222 * type of "mtu": rt_mtu is u_long, ifnet.ifr_mtu is int, and 223 * nd_ifinfo.linkmtu is u_int32_t. so we use u_long to hold largest one, 224 * which is rt_mtu. 225 * 226 * ifpp - XXX: just for statistics 227 */ 228 int 229 ip6_output(struct mbuf *m0, struct ip6_pktopts *opt, 230 struct route_in6 *ro, int flags, struct ip6_moptions *im6o, 231 struct ifnet **ifpp, struct inpcb *inp) 232 { 233 struct ip6_hdr *ip6, *mhip6; 234 struct ifnet *ifp, *origifp; 235 struct mbuf *m = m0; 236 struct mbuf *mprev = NULL; 237 int hlen, tlen, len, off; 238 struct route_in6 ip6route; 239 struct rtentry *rt = NULL; 240 struct sockaddr_in6 *dst, src_sa, dst_sa; 241 struct in6_addr odst; 242 int error = 0; 243 struct in6_ifaddr *ia = NULL; 244 u_long mtu; 245 int alwaysfrag, dontfrag; 246 u_int32_t optlen = 0, plen = 0, unfragpartlen = 0; 247 struct ip6_exthdrs exthdrs; 248 struct in6_addr finaldst, src0, dst0; 249 u_int32_t zone; 250 struct route_in6 *ro_pmtu = NULL; 251 int hdrsplit = 0; 252 int sw_csum, tso; 253 struct m_tag *fwd_tag = NULL; 254 255 ip6 = mtod(m, struct ip6_hdr *); 256 if (ip6 == NULL) { 257 printf ("ip6 is NULL"); 258 goto bad; 259 } 260 261 if (inp != NULL) 262 M_SETFIB(m, inp->inp_inc.inc_fibnum); 263 264 finaldst = ip6->ip6_dst; 265 bzero(&exthdrs, sizeof(exthdrs)); 266 if (opt) { 267 /* Hop-by-Hop options header */ 268 MAKE_EXTHDR(opt->ip6po_hbh, &exthdrs.ip6e_hbh); 269 /* Destination options header(1st part) */ 270 if (opt->ip6po_rthdr) { 271 /* 272 * Destination options header(1st part) 273 * This only makes sense with a routing header. 274 * See Section 9.2 of RFC 3542. 275 * Disabling this part just for MIP6 convenience is 276 * a bad idea. We need to think carefully about a 277 * way to make the advanced API coexist with MIP6 278 * options, which might automatically be inserted in 279 * the kernel. 280 */ 281 MAKE_EXTHDR(opt->ip6po_dest1, &exthdrs.ip6e_dest1); 282 } 283 /* Routing header */ 284 MAKE_EXTHDR(opt->ip6po_rthdr, &exthdrs.ip6e_rthdr); 285 /* Destination options header(2nd part) */ 286 MAKE_EXTHDR(opt->ip6po_dest2, &exthdrs.ip6e_dest2); 287 } 288 289 #ifdef IPSEC 290 /* 291 * IPSec checking which handles several cases. 292 * FAST IPSEC: We re-injected the packet. 293 */ 294 switch(ip6_ipsec_output(&m, inp, &flags, &error, &ifp)) 295 { 296 case 1: /* Bad packet */ 297 goto freehdrs; 298 case -1: /* IPSec done */ 299 goto done; 300 case 0: /* No IPSec */ 301 default: 302 break; 303 } 304 #endif /* IPSEC */ 305 306 /* 307 * Calculate the total length of the extension header chain. 308 * Keep the length of the unfragmentable part for fragmentation. 309 */ 310 optlen = 0; 311 if (exthdrs.ip6e_hbh) 312 optlen += exthdrs.ip6e_hbh->m_len; 313 if (exthdrs.ip6e_dest1) 314 optlen += exthdrs.ip6e_dest1->m_len; 315 if (exthdrs.ip6e_rthdr) 316 optlen += exthdrs.ip6e_rthdr->m_len; 317 unfragpartlen = optlen + sizeof(struct ip6_hdr); 318 319 /* NOTE: we don't add AH/ESP length here (done in ip6_ipsec_output) */ 320 if (exthdrs.ip6e_dest2) 321 optlen += exthdrs.ip6e_dest2->m_len; 322 323 /* 324 * If there is at least one extension header, 325 * separate IP6 header from the payload. 326 */ 327 if (optlen && !hdrsplit) { 328 if ((error = ip6_splithdr(m, &exthdrs)) != 0) { 329 m = NULL; 330 goto freehdrs; 331 } 332 m = exthdrs.ip6e_ip6; 333 hdrsplit++; 334 } 335 336 /* adjust pointer */ 337 ip6 = mtod(m, struct ip6_hdr *); 338 339 /* adjust mbuf packet header length */ 340 m->m_pkthdr.len += optlen; 341 plen = m->m_pkthdr.len - sizeof(*ip6); 342 343 /* If this is a jumbo payload, insert a jumbo payload option. */ 344 if (plen > IPV6_MAXPACKET) { 345 if (!hdrsplit) { 346 if ((error = ip6_splithdr(m, &exthdrs)) != 0) { 347 m = NULL; 348 goto freehdrs; 349 } 350 m = exthdrs.ip6e_ip6; 351 hdrsplit++; 352 } 353 /* adjust pointer */ 354 ip6 = mtod(m, struct ip6_hdr *); 355 if ((error = ip6_insert_jumboopt(&exthdrs, plen)) != 0) 356 goto freehdrs; 357 ip6->ip6_plen = 0; 358 } else 359 ip6->ip6_plen = htons(plen); 360 361 /* 362 * Concatenate headers and fill in next header fields. 363 * Here we have, on "m" 364 * IPv6 payload 365 * and we insert headers accordingly. Finally, we should be getting: 366 * IPv6 hbh dest1 rthdr ah* [esp* dest2 payload] 367 * 368 * during the header composing process, "m" points to IPv6 header. 369 * "mprev" points to an extension header prior to esp. 370 */ 371 u_char *nexthdrp = &ip6->ip6_nxt; 372 mprev = m; 373 374 /* 375 * we treat dest2 specially. this makes IPsec processing 376 * much easier. the goal here is to make mprev point the 377 * mbuf prior to dest2. 378 * 379 * result: IPv6 dest2 payload 380 * m and mprev will point to IPv6 header. 381 */ 382 if (exthdrs.ip6e_dest2) { 383 if (!hdrsplit) 384 panic("assumption failed: hdr not split"); 385 exthdrs.ip6e_dest2->m_next = m->m_next; 386 m->m_next = exthdrs.ip6e_dest2; 387 *mtod(exthdrs.ip6e_dest2, u_char *) = ip6->ip6_nxt; 388 ip6->ip6_nxt = IPPROTO_DSTOPTS; 389 } 390 391 /* 392 * result: IPv6 hbh dest1 rthdr dest2 payload 393 * m will point to IPv6 header. mprev will point to the 394 * extension header prior to dest2 (rthdr in the above case). 395 */ 396 MAKE_CHAIN(exthdrs.ip6e_hbh, mprev, nexthdrp, IPPROTO_HOPOPTS); 397 MAKE_CHAIN(exthdrs.ip6e_dest1, mprev, nexthdrp, 398 IPPROTO_DSTOPTS); 399 MAKE_CHAIN(exthdrs.ip6e_rthdr, mprev, nexthdrp, 400 IPPROTO_ROUTING); 401 402 /* 403 * If there is a routing header, discard the packet. 404 */ 405 if (exthdrs.ip6e_rthdr) { 406 error = EINVAL; 407 goto bad; 408 } 409 410 /* Source address validation */ 411 if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) && 412 (flags & IPV6_UNSPECSRC) == 0) { 413 error = EOPNOTSUPP; 414 IP6STAT_INC(ip6s_badscope); 415 goto bad; 416 } 417 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_src)) { 418 error = EOPNOTSUPP; 419 IP6STAT_INC(ip6s_badscope); 420 goto bad; 421 } 422 423 IP6STAT_INC(ip6s_localout); 424 425 /* 426 * Route packet. 427 */ 428 if (ro == 0) { 429 ro = &ip6route; 430 bzero((caddr_t)ro, sizeof(*ro)); 431 } 432 ro_pmtu = ro; 433 if (opt && opt->ip6po_rthdr) 434 ro = &opt->ip6po_route; 435 dst = (struct sockaddr_in6 *)&ro->ro_dst; 436 #ifdef FLOWTABLE 437 if (ro->ro_rt == NULL) 438 (void )flowtable_lookup(AF_INET6, m, (struct route *)ro); 439 #endif 440 again: 441 /* 442 * if specified, try to fill in the traffic class field. 443 * do not override if a non-zero value is already set. 444 * we check the diffserv field and the ecn field separately. 445 */ 446 if (opt && opt->ip6po_tclass >= 0) { 447 int mask = 0; 448 449 if ((ip6->ip6_flow & htonl(0xfc << 20)) == 0) 450 mask |= 0xfc; 451 if ((ip6->ip6_flow & htonl(0x03 << 20)) == 0) 452 mask |= 0x03; 453 if (mask != 0) 454 ip6->ip6_flow |= htonl((opt->ip6po_tclass & mask) << 20); 455 } 456 457 /* fill in or override the hop limit field, if necessary. */ 458 if (opt && opt->ip6po_hlim != -1) 459 ip6->ip6_hlim = opt->ip6po_hlim & 0xff; 460 else if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 461 if (im6o != NULL) 462 ip6->ip6_hlim = im6o->im6o_multicast_hlim; 463 else 464 ip6->ip6_hlim = V_ip6_defmcasthlim; 465 } 466 467 /* adjust pointer */ 468 ip6 = mtod(m, struct ip6_hdr *); 469 470 if (ro->ro_rt && fwd_tag == NULL) { 471 rt = ro->ro_rt; 472 ifp = ro->ro_rt->rt_ifp; 473 } else { 474 if (fwd_tag == NULL) { 475 bzero(&dst_sa, sizeof(dst_sa)); 476 dst_sa.sin6_family = AF_INET6; 477 dst_sa.sin6_len = sizeof(dst_sa); 478 dst_sa.sin6_addr = ip6->ip6_dst; 479 } 480 error = in6_selectroute_fib(&dst_sa, opt, im6o, ro, &ifp, 481 &rt, inp ? inp->inp_inc.inc_fibnum : M_GETFIB(m)); 482 if (error != 0) { 483 if (ifp != NULL) 484 in6_ifstat_inc(ifp, ifs6_out_discard); 485 goto bad; 486 } 487 } 488 if (rt == NULL) { 489 /* 490 * If in6_selectroute() does not return a route entry, 491 * dst may not have been updated. 492 */ 493 *dst = dst_sa; /* XXX */ 494 } 495 496 /* 497 * then rt (for unicast) and ifp must be non-NULL valid values. 498 */ 499 if ((flags & IPV6_FORWARDING) == 0) { 500 /* XXX: the FORWARDING flag can be set for mrouting. */ 501 in6_ifstat_inc(ifp, ifs6_out_request); 502 } 503 if (rt != NULL) { 504 ia = (struct in6_ifaddr *)(rt->rt_ifa); 505 counter_u64_add(rt->rt_pksent, 1); 506 } 507 508 509 /* 510 * The outgoing interface must be in the zone of source and 511 * destination addresses. 512 */ 513 origifp = ifp; 514 515 src0 = ip6->ip6_src; 516 if (in6_setscope(&src0, origifp, &zone)) 517 goto badscope; 518 bzero(&src_sa, sizeof(src_sa)); 519 src_sa.sin6_family = AF_INET6; 520 src_sa.sin6_len = sizeof(src_sa); 521 src_sa.sin6_addr = ip6->ip6_src; 522 if (sa6_recoverscope(&src_sa) || zone != src_sa.sin6_scope_id) 523 goto badscope; 524 525 dst0 = ip6->ip6_dst; 526 if (in6_setscope(&dst0, origifp, &zone)) 527 goto badscope; 528 /* re-initialize to be sure */ 529 bzero(&dst_sa, sizeof(dst_sa)); 530 dst_sa.sin6_family = AF_INET6; 531 dst_sa.sin6_len = sizeof(dst_sa); 532 dst_sa.sin6_addr = ip6->ip6_dst; 533 if (sa6_recoverscope(&dst_sa) || zone != dst_sa.sin6_scope_id) { 534 goto badscope; 535 } 536 537 /* We should use ia_ifp to support the case of 538 * sending packets to an address of our own. 539 */ 540 if (ia != NULL && ia->ia_ifp) 541 ifp = ia->ia_ifp; 542 543 /* scope check is done. */ 544 goto routefound; 545 546 badscope: 547 IP6STAT_INC(ip6s_badscope); 548 in6_ifstat_inc(origifp, ifs6_out_discard); 549 if (error == 0) 550 error = EHOSTUNREACH; /* XXX */ 551 goto bad; 552 553 routefound: 554 if (rt && !IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 555 if (opt && opt->ip6po_nextroute.ro_rt) { 556 /* 557 * The nexthop is explicitly specified by the 558 * application. We assume the next hop is an IPv6 559 * address. 560 */ 561 dst = (struct sockaddr_in6 *)opt->ip6po_nexthop; 562 } 563 else if ((rt->rt_flags & RTF_GATEWAY)) 564 dst = (struct sockaddr_in6 *)rt->rt_gateway; 565 } 566 567 if (!IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 568 m->m_flags &= ~(M_BCAST | M_MCAST); /* just in case */ 569 } else { 570 m->m_flags = (m->m_flags & ~M_BCAST) | M_MCAST; 571 in6_ifstat_inc(ifp, ifs6_out_mcast); 572 /* 573 * Confirm that the outgoing interface supports multicast. 574 */ 575 if (!(ifp->if_flags & IFF_MULTICAST)) { 576 IP6STAT_INC(ip6s_noroute); 577 in6_ifstat_inc(ifp, ifs6_out_discard); 578 error = ENETUNREACH; 579 goto bad; 580 } 581 if ((im6o == NULL && in6_mcast_loop) || 582 (im6o && im6o->im6o_multicast_loop)) { 583 /* 584 * Loop back multicast datagram if not expressly 585 * forbidden to do so, even if we have not joined 586 * the address; protocols will filter it later, 587 * thus deferring a hash lookup and lock acquisition 588 * at the expense of an m_copym(). 589 */ 590 ip6_mloopback(ifp, m, dst); 591 } else { 592 /* 593 * If we are acting as a multicast router, perform 594 * multicast forwarding as if the packet had just 595 * arrived on the interface to which we are about 596 * to send. The multicast forwarding function 597 * recursively calls this function, using the 598 * IPV6_FORWARDING flag to prevent infinite recursion. 599 * 600 * Multicasts that are looped back by ip6_mloopback(), 601 * above, will be forwarded by the ip6_input() routine, 602 * if necessary. 603 */ 604 if (V_ip6_mrouter && (flags & IPV6_FORWARDING) == 0) { 605 /* 606 * XXX: ip6_mforward expects that rcvif is NULL 607 * when it is called from the originating path. 608 * However, it may not always be the case. 609 */ 610 m->m_pkthdr.rcvif = NULL; 611 if (ip6_mforward(ip6, ifp, m) != 0) { 612 m_freem(m); 613 goto done; 614 } 615 } 616 } 617 /* 618 * Multicasts with a hoplimit of zero may be looped back, 619 * above, but must not be transmitted on a network. 620 * Also, multicasts addressed to the loopback interface 621 * are not sent -- the above call to ip6_mloopback() will 622 * loop back a copy if this host actually belongs to the 623 * destination group on the loopback interface. 624 */ 625 if (ip6->ip6_hlim == 0 || (ifp->if_flags & IFF_LOOPBACK) || 626 IN6_IS_ADDR_MC_INTFACELOCAL(&ip6->ip6_dst)) { 627 m_freem(m); 628 goto done; 629 } 630 } 631 632 /* 633 * Fill the outgoing inteface to tell the upper layer 634 * to increment per-interface statistics. 635 */ 636 if (ifpp) 637 *ifpp = ifp; 638 639 /* Determine path MTU. */ 640 if ((error = ip6_getpmtu(ro_pmtu, ro, ifp, &finaldst, &mtu, 641 &alwaysfrag, inp ? inp->inp_inc.inc_fibnum : M_GETFIB(m))) != 0) 642 goto bad; 643 644 /* 645 * The caller of this function may specify to use the minimum MTU 646 * in some cases. 647 * An advanced API option (IPV6_USE_MIN_MTU) can also override MTU 648 * setting. The logic is a bit complicated; by default, unicast 649 * packets will follow path MTU while multicast packets will be sent at 650 * the minimum MTU. If IP6PO_MINMTU_ALL is specified, all packets 651 * including unicast ones will be sent at the minimum MTU. Multicast 652 * packets will always be sent at the minimum MTU unless 653 * IP6PO_MINMTU_DISABLE is explicitly specified. 654 * See RFC 3542 for more details. 655 */ 656 if (mtu > IPV6_MMTU) { 657 if ((flags & IPV6_MINMTU)) 658 mtu = IPV6_MMTU; 659 else if (opt && opt->ip6po_minmtu == IP6PO_MINMTU_ALL) 660 mtu = IPV6_MMTU; 661 else if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) && 662 (opt == NULL || 663 opt->ip6po_minmtu != IP6PO_MINMTU_DISABLE)) { 664 mtu = IPV6_MMTU; 665 } 666 } 667 668 /* 669 * clear embedded scope identifiers if necessary. 670 * in6_clearscope will touch the addresses only when necessary. 671 */ 672 in6_clearscope(&ip6->ip6_src); 673 in6_clearscope(&ip6->ip6_dst); 674 675 /* 676 * If the outgoing packet contains a hop-by-hop options header, 677 * it must be examined and processed even by the source node. 678 * (RFC 2460, section 4.) 679 */ 680 if (exthdrs.ip6e_hbh) { 681 struct ip6_hbh *hbh = mtod(exthdrs.ip6e_hbh, struct ip6_hbh *); 682 u_int32_t dummy; /* XXX unused */ 683 u_int32_t plen = 0; /* XXX: ip6_process will check the value */ 684 685 #ifdef DIAGNOSTIC 686 if ((hbh->ip6h_len + 1) << 3 > exthdrs.ip6e_hbh->m_len) 687 panic("ip6e_hbh is not contiguous"); 688 #endif 689 /* 690 * XXX: if we have to send an ICMPv6 error to the sender, 691 * we need the M_LOOP flag since icmp6_error() expects 692 * the IPv6 and the hop-by-hop options header are 693 * contiguous unless the flag is set. 694 */ 695 m->m_flags |= M_LOOP; 696 m->m_pkthdr.rcvif = ifp; 697 if (ip6_process_hopopts(m, (u_int8_t *)(hbh + 1), 698 ((hbh->ip6h_len + 1) << 3) - sizeof(struct ip6_hbh), 699 &dummy, &plen) < 0) { 700 /* m was already freed at this point */ 701 error = EINVAL;/* better error? */ 702 goto done; 703 } 704 m->m_flags &= ~M_LOOP; /* XXX */ 705 m->m_pkthdr.rcvif = NULL; 706 } 707 708 /* Jump over all PFIL processing if hooks are not active. */ 709 if (!PFIL_HOOKED(&V_inet6_pfil_hook)) 710 goto passout; 711 712 odst = ip6->ip6_dst; 713 /* Run through list of hooks for output packets. */ 714 error = pfil_run_hooks(&V_inet6_pfil_hook, &m, ifp, PFIL_OUT, inp); 715 if (error != 0 || m == NULL) 716 goto done; 717 ip6 = mtod(m, struct ip6_hdr *); 718 719 /* See if destination IP address was changed by packet filter. */ 720 if (!IN6_ARE_ADDR_EQUAL(&odst, &ip6->ip6_dst)) { 721 m->m_flags |= M_SKIP_FIREWALL; 722 /* If destination is now ourself drop to ip6_input(). */ 723 if (in6_localip(&ip6->ip6_dst)) { 724 m->m_flags |= M_FASTFWD_OURS; 725 if (m->m_pkthdr.rcvif == NULL) 726 m->m_pkthdr.rcvif = V_loif; 727 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) { 728 m->m_pkthdr.csum_flags |= 729 CSUM_DATA_VALID_IPV6 | CSUM_PSEUDO_HDR; 730 m->m_pkthdr.csum_data = 0xffff; 731 } 732 #ifdef SCTP 733 if (m->m_pkthdr.csum_flags & CSUM_SCTP_IPV6) 734 m->m_pkthdr.csum_flags |= CSUM_SCTP_VALID; 735 #endif 736 error = netisr_queue(NETISR_IPV6, m); 737 goto done; 738 } else 739 goto again; /* Redo the routing table lookup. */ 740 } 741 742 /* See if local, if yes, send it to netisr. */ 743 if (m->m_flags & M_FASTFWD_OURS) { 744 if (m->m_pkthdr.rcvif == NULL) 745 m->m_pkthdr.rcvif = V_loif; 746 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) { 747 m->m_pkthdr.csum_flags |= 748 CSUM_DATA_VALID_IPV6 | CSUM_PSEUDO_HDR; 749 m->m_pkthdr.csum_data = 0xffff; 750 } 751 #ifdef SCTP 752 if (m->m_pkthdr.csum_flags & CSUM_SCTP_IPV6) 753 m->m_pkthdr.csum_flags |= CSUM_SCTP_VALID; 754 #endif 755 error = netisr_queue(NETISR_IPV6, m); 756 goto done; 757 } 758 /* Or forward to some other address? */ 759 if ((m->m_flags & M_IP6_NEXTHOP) && 760 (fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL)) != NULL) { 761 dst = (struct sockaddr_in6 *)&ro->ro_dst; 762 bcopy((fwd_tag+1), &dst_sa, sizeof(struct sockaddr_in6)); 763 m->m_flags |= M_SKIP_FIREWALL; 764 m->m_flags &= ~M_IP6_NEXTHOP; 765 m_tag_delete(m, fwd_tag); 766 goto again; 767 } 768 769 passout: 770 /* 771 * Send the packet to the outgoing interface. 772 * If necessary, do IPv6 fragmentation before sending. 773 * 774 * the logic here is rather complex: 775 * 1: normal case (dontfrag == 0, alwaysfrag == 0) 776 * 1-a: send as is if tlen <= path mtu 777 * 1-b: fragment if tlen > path mtu 778 * 779 * 2: if user asks us not to fragment (dontfrag == 1) 780 * 2-a: send as is if tlen <= interface mtu 781 * 2-b: error if tlen > interface mtu 782 * 783 * 3: if we always need to attach fragment header (alwaysfrag == 1) 784 * always fragment 785 * 786 * 4: if dontfrag == 1 && alwaysfrag == 1 787 * error, as we cannot handle this conflicting request 788 */ 789 sw_csum = m->m_pkthdr.csum_flags; 790 if (!hdrsplit) { 791 tso = ((sw_csum & ifp->if_hwassist & CSUM_TSO) != 0) ? 1 : 0; 792 sw_csum &= ~ifp->if_hwassist; 793 } else 794 tso = 0; 795 /* 796 * If we added extension headers, we will not do TSO and calculate the 797 * checksums ourselves for now. 798 * XXX-BZ Need a framework to know when the NIC can handle it, even 799 * with ext. hdrs. 800 */ 801 if (sw_csum & CSUM_DELAY_DATA_IPV6) { 802 sw_csum &= ~CSUM_DELAY_DATA_IPV6; 803 in6_delayed_cksum(m, plen, sizeof(struct ip6_hdr)); 804 } 805 #ifdef SCTP 806 if (sw_csum & CSUM_SCTP_IPV6) { 807 sw_csum &= ~CSUM_SCTP_IPV6; 808 sctp_delayed_cksum(m, sizeof(struct ip6_hdr)); 809 } 810 #endif 811 m->m_pkthdr.csum_flags &= ifp->if_hwassist; 812 tlen = m->m_pkthdr.len; 813 814 if ((opt && (opt->ip6po_flags & IP6PO_DONTFRAG)) || tso) 815 dontfrag = 1; 816 else 817 dontfrag = 0; 818 if (dontfrag && alwaysfrag) { /* case 4 */ 819 /* conflicting request - can't transmit */ 820 error = EMSGSIZE; 821 goto bad; 822 } 823 if (dontfrag && tlen > IN6_LINKMTU(ifp) && !tso) { /* case 2-b */ 824 /* 825 * Even if the DONTFRAG option is specified, we cannot send the 826 * packet when the data length is larger than the MTU of the 827 * outgoing interface. 828 * Notify the error by sending IPV6_PATHMTU ancillary data as 829 * well as returning an error code (the latter is not described 830 * in the API spec.) 831 */ 832 u_int32_t mtu32; 833 struct ip6ctlparam ip6cp; 834 835 mtu32 = (u_int32_t)mtu; 836 bzero(&ip6cp, sizeof(ip6cp)); 837 ip6cp.ip6c_cmdarg = (void *)&mtu32; 838 pfctlinput2(PRC_MSGSIZE, (struct sockaddr *)&ro_pmtu->ro_dst, 839 (void *)&ip6cp); 840 841 error = EMSGSIZE; 842 goto bad; 843 } 844 845 /* 846 * transmit packet without fragmentation 847 */ 848 if (dontfrag || (!alwaysfrag && tlen <= mtu)) { /* case 1-a and 2-a */ 849 struct in6_ifaddr *ia6; 850 851 ip6 = mtod(m, struct ip6_hdr *); 852 ia6 = in6_ifawithifp(ifp, &ip6->ip6_src); 853 if (ia6) { 854 /* Record statistics for this interface address. */ 855 counter_u64_add(ia6->ia_ifa.ifa_opackets, 1); 856 counter_u64_add(ia6->ia_ifa.ifa_obytes, 857 m->m_pkthdr.len); 858 ifa_free(&ia6->ia_ifa); 859 } 860 error = nd6_output(ifp, origifp, m, dst, ro->ro_rt); 861 goto done; 862 } 863 864 /* 865 * try to fragment the packet. case 1-b and 3 866 */ 867 if (mtu < IPV6_MMTU) { 868 /* path MTU cannot be less than IPV6_MMTU */ 869 error = EMSGSIZE; 870 in6_ifstat_inc(ifp, ifs6_out_fragfail); 871 goto bad; 872 } else if (ip6->ip6_plen == 0) { 873 /* jumbo payload cannot be fragmented */ 874 error = EMSGSIZE; 875 in6_ifstat_inc(ifp, ifs6_out_fragfail); 876 goto bad; 877 } else { 878 struct mbuf **mnext, *m_frgpart; 879 struct ip6_frag *ip6f; 880 u_int32_t id = htonl(ip6_randomid()); 881 u_char nextproto; 882 883 int qslots = ifp->if_snd.ifq_maxlen - ifp->if_snd.ifq_len; 884 885 /* 886 * Too large for the destination or interface; 887 * fragment if possible. 888 * Must be able to put at least 8 bytes per fragment. 889 */ 890 hlen = unfragpartlen; 891 if (mtu > IPV6_MAXPACKET) 892 mtu = IPV6_MAXPACKET; 893 894 len = (mtu - hlen - sizeof(struct ip6_frag)) & ~7; 895 if (len < 8) { 896 error = EMSGSIZE; 897 in6_ifstat_inc(ifp, ifs6_out_fragfail); 898 goto bad; 899 } 900 901 /* 902 * Verify that we have any chance at all of being able to queue 903 * the packet or packet fragments 904 */ 905 if (qslots <= 0 || ((u_int)qslots * (mtu - hlen) 906 < tlen /* - hlen */)) { 907 error = ENOBUFS; 908 IP6STAT_INC(ip6s_odropped); 909 goto bad; 910 } 911 912 913 /* 914 * If the interface will not calculate checksums on 915 * fragmented packets, then do it here. 916 * XXX-BZ handle the hw offloading case. Need flags. 917 */ 918 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) { 919 in6_delayed_cksum(m, plen, hlen); 920 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA_IPV6; 921 } 922 #ifdef SCTP 923 if (m->m_pkthdr.csum_flags & CSUM_SCTP_IPV6) { 924 sctp_delayed_cksum(m, hlen); 925 m->m_pkthdr.csum_flags &= ~CSUM_SCTP_IPV6; 926 } 927 #endif 928 mnext = &m->m_nextpkt; 929 930 /* 931 * Change the next header field of the last header in the 932 * unfragmentable part. 933 */ 934 if (exthdrs.ip6e_rthdr) { 935 nextproto = *mtod(exthdrs.ip6e_rthdr, u_char *); 936 *mtod(exthdrs.ip6e_rthdr, u_char *) = IPPROTO_FRAGMENT; 937 } else if (exthdrs.ip6e_dest1) { 938 nextproto = *mtod(exthdrs.ip6e_dest1, u_char *); 939 *mtod(exthdrs.ip6e_dest1, u_char *) = IPPROTO_FRAGMENT; 940 } else if (exthdrs.ip6e_hbh) { 941 nextproto = *mtod(exthdrs.ip6e_hbh, u_char *); 942 *mtod(exthdrs.ip6e_hbh, u_char *) = IPPROTO_FRAGMENT; 943 } else { 944 nextproto = ip6->ip6_nxt; 945 ip6->ip6_nxt = IPPROTO_FRAGMENT; 946 } 947 948 /* 949 * Loop through length of segment after first fragment, 950 * make new header and copy data of each part and link onto 951 * chain. 952 */ 953 m0 = m; 954 for (off = hlen; off < tlen; off += len) { 955 m = m_gethdr(M_NOWAIT, MT_DATA); 956 if (!m) { 957 error = ENOBUFS; 958 IP6STAT_INC(ip6s_odropped); 959 goto sendorfree; 960 } 961 m->m_flags = m0->m_flags & M_COPYFLAGS; 962 *mnext = m; 963 mnext = &m->m_nextpkt; 964 m->m_data += max_linkhdr; 965 mhip6 = mtod(m, struct ip6_hdr *); 966 *mhip6 = *ip6; 967 m->m_len = sizeof(*mhip6); 968 error = ip6_insertfraghdr(m0, m, hlen, &ip6f); 969 if (error) { 970 IP6STAT_INC(ip6s_odropped); 971 goto sendorfree; 972 } 973 ip6f->ip6f_offlg = htons((u_short)((off - hlen) & ~7)); 974 if (off + len >= tlen) 975 len = tlen - off; 976 else 977 ip6f->ip6f_offlg |= IP6F_MORE_FRAG; 978 mhip6->ip6_plen = htons((u_short)(len + hlen + 979 sizeof(*ip6f) - sizeof(struct ip6_hdr))); 980 if ((m_frgpart = m_copy(m0, off, len)) == 0) { 981 error = ENOBUFS; 982 IP6STAT_INC(ip6s_odropped); 983 goto sendorfree; 984 } 985 m_cat(m, m_frgpart); 986 m->m_pkthdr.len = len + hlen + sizeof(*ip6f); 987 m->m_pkthdr.fibnum = m0->m_pkthdr.fibnum; 988 m->m_pkthdr.rcvif = NULL; 989 ip6f->ip6f_reserved = 0; 990 ip6f->ip6f_ident = id; 991 ip6f->ip6f_nxt = nextproto; 992 IP6STAT_INC(ip6s_ofragments); 993 in6_ifstat_inc(ifp, ifs6_out_fragcreat); 994 } 995 996 in6_ifstat_inc(ifp, ifs6_out_fragok); 997 } 998 999 /* 1000 * Remove leading garbages. 1001 */ 1002 sendorfree: 1003 m = m0->m_nextpkt; 1004 m0->m_nextpkt = 0; 1005 m_freem(m0); 1006 for (m0 = m; m; m = m0) { 1007 m0 = m->m_nextpkt; 1008 m->m_nextpkt = 0; 1009 if (error == 0) { 1010 /* Record statistics for this interface address. */ 1011 if (ia) { 1012 counter_u64_add(ia->ia_ifa.ifa_opackets, 1); 1013 counter_u64_add(ia->ia_ifa.ifa_obytes, 1014 m->m_pkthdr.len); 1015 } 1016 error = nd6_output(ifp, origifp, m, dst, ro->ro_rt); 1017 } else 1018 m_freem(m); 1019 } 1020 1021 if (error == 0) 1022 IP6STAT_INC(ip6s_fragmented); 1023 1024 done: 1025 if (ro == &ip6route) 1026 RO_RTFREE(ro); 1027 if (ro_pmtu == &ip6route) 1028 RO_RTFREE(ro_pmtu); 1029 return (error); 1030 1031 freehdrs: 1032 m_freem(exthdrs.ip6e_hbh); /* m_freem will check if mbuf is 0 */ 1033 m_freem(exthdrs.ip6e_dest1); 1034 m_freem(exthdrs.ip6e_rthdr); 1035 m_freem(exthdrs.ip6e_dest2); 1036 /* FALLTHROUGH */ 1037 bad: 1038 if (m) 1039 m_freem(m); 1040 goto done; 1041 } 1042 1043 static int 1044 ip6_copyexthdr(struct mbuf **mp, caddr_t hdr, int hlen) 1045 { 1046 struct mbuf *m; 1047 1048 if (hlen > MCLBYTES) 1049 return (ENOBUFS); /* XXX */ 1050 1051 if (hlen > MLEN) 1052 m = m_getcl(M_NOWAIT, MT_DATA, 0); 1053 else 1054 m = m_get(M_NOWAIT, MT_DATA); 1055 if (m == NULL) 1056 return (ENOBUFS); 1057 m->m_len = hlen; 1058 if (hdr) 1059 bcopy(hdr, mtod(m, caddr_t), hlen); 1060 1061 *mp = m; 1062 return (0); 1063 } 1064 1065 /* 1066 * Insert jumbo payload option. 1067 */ 1068 static int 1069 ip6_insert_jumboopt(struct ip6_exthdrs *exthdrs, u_int32_t plen) 1070 { 1071 struct mbuf *mopt; 1072 u_char *optbuf; 1073 u_int32_t v; 1074 1075 #define JUMBOOPTLEN 8 /* length of jumbo payload option and padding */ 1076 1077 /* 1078 * If there is no hop-by-hop options header, allocate new one. 1079 * If there is one but it doesn't have enough space to store the 1080 * jumbo payload option, allocate a cluster to store the whole options. 1081 * Otherwise, use it to store the options. 1082 */ 1083 if (exthdrs->ip6e_hbh == 0) { 1084 mopt = m_get(M_NOWAIT, MT_DATA); 1085 if (mopt == NULL) 1086 return (ENOBUFS); 1087 mopt->m_len = JUMBOOPTLEN; 1088 optbuf = mtod(mopt, u_char *); 1089 optbuf[1] = 0; /* = ((JUMBOOPTLEN) >> 3) - 1 */ 1090 exthdrs->ip6e_hbh = mopt; 1091 } else { 1092 struct ip6_hbh *hbh; 1093 1094 mopt = exthdrs->ip6e_hbh; 1095 if (M_TRAILINGSPACE(mopt) < JUMBOOPTLEN) { 1096 /* 1097 * XXX assumption: 1098 * - exthdrs->ip6e_hbh is not referenced from places 1099 * other than exthdrs. 1100 * - exthdrs->ip6e_hbh is not an mbuf chain. 1101 */ 1102 int oldoptlen = mopt->m_len; 1103 struct mbuf *n; 1104 1105 /* 1106 * XXX: give up if the whole (new) hbh header does 1107 * not fit even in an mbuf cluster. 1108 */ 1109 if (oldoptlen + JUMBOOPTLEN > MCLBYTES) 1110 return (ENOBUFS); 1111 1112 /* 1113 * As a consequence, we must always prepare a cluster 1114 * at this point. 1115 */ 1116 n = m_getcl(M_NOWAIT, MT_DATA, 0); 1117 if (n == NULL) 1118 return (ENOBUFS); 1119 n->m_len = oldoptlen + JUMBOOPTLEN; 1120 bcopy(mtod(mopt, caddr_t), mtod(n, caddr_t), 1121 oldoptlen); 1122 optbuf = mtod(n, caddr_t) + oldoptlen; 1123 m_freem(mopt); 1124 mopt = exthdrs->ip6e_hbh = n; 1125 } else { 1126 optbuf = mtod(mopt, u_char *) + mopt->m_len; 1127 mopt->m_len += JUMBOOPTLEN; 1128 } 1129 optbuf[0] = IP6OPT_PADN; 1130 optbuf[1] = 1; 1131 1132 /* 1133 * Adjust the header length according to the pad and 1134 * the jumbo payload option. 1135 */ 1136 hbh = mtod(mopt, struct ip6_hbh *); 1137 hbh->ip6h_len += (JUMBOOPTLEN >> 3); 1138 } 1139 1140 /* fill in the option. */ 1141 optbuf[2] = IP6OPT_JUMBO; 1142 optbuf[3] = 4; 1143 v = (u_int32_t)htonl(plen + JUMBOOPTLEN); 1144 bcopy(&v, &optbuf[4], sizeof(u_int32_t)); 1145 1146 /* finally, adjust the packet header length */ 1147 exthdrs->ip6e_ip6->m_pkthdr.len += JUMBOOPTLEN; 1148 1149 return (0); 1150 #undef JUMBOOPTLEN 1151 } 1152 1153 /* 1154 * Insert fragment header and copy unfragmentable header portions. 1155 */ 1156 static int 1157 ip6_insertfraghdr(struct mbuf *m0, struct mbuf *m, int hlen, 1158 struct ip6_frag **frghdrp) 1159 { 1160 struct mbuf *n, *mlast; 1161 1162 if (hlen > sizeof(struct ip6_hdr)) { 1163 n = m_copym(m0, sizeof(struct ip6_hdr), 1164 hlen - sizeof(struct ip6_hdr), M_NOWAIT); 1165 if (n == 0) 1166 return (ENOBUFS); 1167 m->m_next = n; 1168 } else 1169 n = m; 1170 1171 /* Search for the last mbuf of unfragmentable part. */ 1172 for (mlast = n; mlast->m_next; mlast = mlast->m_next) 1173 ; 1174 1175 if ((mlast->m_flags & M_EXT) == 0 && 1176 M_TRAILINGSPACE(mlast) >= sizeof(struct ip6_frag)) { 1177 /* use the trailing space of the last mbuf for the fragment hdr */ 1178 *frghdrp = (struct ip6_frag *)(mtod(mlast, caddr_t) + 1179 mlast->m_len); 1180 mlast->m_len += sizeof(struct ip6_frag); 1181 m->m_pkthdr.len += sizeof(struct ip6_frag); 1182 } else { 1183 /* allocate a new mbuf for the fragment header */ 1184 struct mbuf *mfrg; 1185 1186 mfrg = m_get(M_NOWAIT, MT_DATA); 1187 if (mfrg == NULL) 1188 return (ENOBUFS); 1189 mfrg->m_len = sizeof(struct ip6_frag); 1190 *frghdrp = mtod(mfrg, struct ip6_frag *); 1191 mlast->m_next = mfrg; 1192 } 1193 1194 return (0); 1195 } 1196 1197 static int 1198 ip6_getpmtu(struct route_in6 *ro_pmtu, struct route_in6 *ro, 1199 struct ifnet *ifp, struct in6_addr *dst, u_long *mtup, 1200 int *alwaysfragp, u_int fibnum) 1201 { 1202 u_int32_t mtu = 0; 1203 int alwaysfrag = 0; 1204 int error = 0; 1205 1206 if (ro_pmtu != ro) { 1207 /* The first hop and the final destination may differ. */ 1208 struct sockaddr_in6 *sa6_dst = 1209 (struct sockaddr_in6 *)&ro_pmtu->ro_dst; 1210 if (ro_pmtu->ro_rt && 1211 ((ro_pmtu->ro_rt->rt_flags & RTF_UP) == 0 || 1212 !IN6_ARE_ADDR_EQUAL(&sa6_dst->sin6_addr, dst))) { 1213 RTFREE(ro_pmtu->ro_rt); 1214 ro_pmtu->ro_rt = (struct rtentry *)NULL; 1215 } 1216 if (ro_pmtu->ro_rt == NULL) { 1217 bzero(sa6_dst, sizeof(*sa6_dst)); 1218 sa6_dst->sin6_family = AF_INET6; 1219 sa6_dst->sin6_len = sizeof(struct sockaddr_in6); 1220 sa6_dst->sin6_addr = *dst; 1221 1222 in6_rtalloc(ro_pmtu, fibnum); 1223 } 1224 } 1225 if (ro_pmtu->ro_rt) { 1226 u_int32_t ifmtu; 1227 struct in_conninfo inc; 1228 1229 bzero(&inc, sizeof(inc)); 1230 inc.inc_flags |= INC_ISIPV6; 1231 inc.inc6_faddr = *dst; 1232 1233 if (ifp == NULL) 1234 ifp = ro_pmtu->ro_rt->rt_ifp; 1235 ifmtu = IN6_LINKMTU(ifp); 1236 mtu = tcp_hc_getmtu(&inc); 1237 if (mtu) 1238 mtu = min(mtu, ro_pmtu->ro_rt->rt_mtu); 1239 else 1240 mtu = ro_pmtu->ro_rt->rt_mtu; 1241 if (mtu == 0) 1242 mtu = ifmtu; 1243 else if (mtu < IPV6_MMTU) { 1244 /* 1245 * RFC2460 section 5, last paragraph: 1246 * if we record ICMPv6 too big message with 1247 * mtu < IPV6_MMTU, transmit packets sized IPV6_MMTU 1248 * or smaller, with framgent header attached. 1249 * (fragment header is needed regardless from the 1250 * packet size, for translators to identify packets) 1251 */ 1252 alwaysfrag = 1; 1253 mtu = IPV6_MMTU; 1254 } else if (mtu > ifmtu) { 1255 /* 1256 * The MTU on the route is larger than the MTU on 1257 * the interface! This shouldn't happen, unless the 1258 * MTU of the interface has been changed after the 1259 * interface was brought up. Change the MTU in the 1260 * route to match the interface MTU (as long as the 1261 * field isn't locked). 1262 */ 1263 mtu = ifmtu; 1264 ro_pmtu->ro_rt->rt_mtu = mtu; 1265 } 1266 } else if (ifp) { 1267 mtu = IN6_LINKMTU(ifp); 1268 } else 1269 error = EHOSTUNREACH; /* XXX */ 1270 1271 *mtup = mtu; 1272 if (alwaysfragp) 1273 *alwaysfragp = alwaysfrag; 1274 return (error); 1275 } 1276 1277 /* 1278 * IP6 socket option processing. 1279 */ 1280 int 1281 ip6_ctloutput(struct socket *so, struct sockopt *sopt) 1282 { 1283 int optdatalen, uproto; 1284 void *optdata; 1285 struct inpcb *in6p = sotoinpcb(so); 1286 int error, optval; 1287 int level, op, optname; 1288 int optlen; 1289 struct thread *td; 1290 1291 level = sopt->sopt_level; 1292 op = sopt->sopt_dir; 1293 optname = sopt->sopt_name; 1294 optlen = sopt->sopt_valsize; 1295 td = sopt->sopt_td; 1296 error = 0; 1297 optval = 0; 1298 uproto = (int)so->so_proto->pr_protocol; 1299 1300 if (level != IPPROTO_IPV6) { 1301 error = EINVAL; 1302 1303 if (sopt->sopt_level == SOL_SOCKET && 1304 sopt->sopt_dir == SOPT_SET) { 1305 switch (sopt->sopt_name) { 1306 case SO_REUSEADDR: 1307 INP_WLOCK(in6p); 1308 if ((so->so_options & SO_REUSEADDR) != 0) 1309 in6p->inp_flags2 |= INP_REUSEADDR; 1310 else 1311 in6p->inp_flags2 &= ~INP_REUSEADDR; 1312 INP_WUNLOCK(in6p); 1313 error = 0; 1314 break; 1315 case SO_REUSEPORT: 1316 INP_WLOCK(in6p); 1317 if ((so->so_options & SO_REUSEPORT) != 0) 1318 in6p->inp_flags2 |= INP_REUSEPORT; 1319 else 1320 in6p->inp_flags2 &= ~INP_REUSEPORT; 1321 INP_WUNLOCK(in6p); 1322 error = 0; 1323 break; 1324 case SO_SETFIB: 1325 INP_WLOCK(in6p); 1326 in6p->inp_inc.inc_fibnum = so->so_fibnum; 1327 INP_WUNLOCK(in6p); 1328 error = 0; 1329 break; 1330 default: 1331 break; 1332 } 1333 } 1334 } else { /* level == IPPROTO_IPV6 */ 1335 switch (op) { 1336 1337 case SOPT_SET: 1338 switch (optname) { 1339 case IPV6_2292PKTOPTIONS: 1340 #ifdef IPV6_PKTOPTIONS 1341 case IPV6_PKTOPTIONS: 1342 #endif 1343 { 1344 struct mbuf *m; 1345 1346 error = soopt_getm(sopt, &m); /* XXX */ 1347 if (error != 0) 1348 break; 1349 error = soopt_mcopyin(sopt, m); /* XXX */ 1350 if (error != 0) 1351 break; 1352 error = ip6_pcbopts(&in6p->in6p_outputopts, 1353 m, so, sopt); 1354 m_freem(m); /* XXX */ 1355 break; 1356 } 1357 1358 /* 1359 * Use of some Hop-by-Hop options or some 1360 * Destination options, might require special 1361 * privilege. That is, normal applications 1362 * (without special privilege) might be forbidden 1363 * from setting certain options in outgoing packets, 1364 * and might never see certain options in received 1365 * packets. [RFC 2292 Section 6] 1366 * KAME specific note: 1367 * KAME prevents non-privileged users from sending or 1368 * receiving ANY hbh/dst options in order to avoid 1369 * overhead of parsing options in the kernel. 1370 */ 1371 case IPV6_RECVHOPOPTS: 1372 case IPV6_RECVDSTOPTS: 1373 case IPV6_RECVRTHDRDSTOPTS: 1374 if (td != NULL) { 1375 error = priv_check(td, 1376 PRIV_NETINET_SETHDROPTS); 1377 if (error) 1378 break; 1379 } 1380 /* FALLTHROUGH */ 1381 case IPV6_UNICAST_HOPS: 1382 case IPV6_HOPLIMIT: 1383 case IPV6_FAITH: 1384 1385 case IPV6_RECVPKTINFO: 1386 case IPV6_RECVHOPLIMIT: 1387 case IPV6_RECVRTHDR: 1388 case IPV6_RECVPATHMTU: 1389 case IPV6_RECVTCLASS: 1390 case IPV6_V6ONLY: 1391 case IPV6_AUTOFLOWLABEL: 1392 case IPV6_BINDANY: 1393 if (optname == IPV6_BINDANY && td != NULL) { 1394 error = priv_check(td, 1395 PRIV_NETINET_BINDANY); 1396 if (error) 1397 break; 1398 } 1399 1400 if (optlen != sizeof(int)) { 1401 error = EINVAL; 1402 break; 1403 } 1404 error = sooptcopyin(sopt, &optval, 1405 sizeof optval, sizeof optval); 1406 if (error) 1407 break; 1408 switch (optname) { 1409 1410 case IPV6_UNICAST_HOPS: 1411 if (optval < -1 || optval >= 256) 1412 error = EINVAL; 1413 else { 1414 /* -1 = kernel default */ 1415 in6p->in6p_hops = optval; 1416 if ((in6p->inp_vflag & 1417 INP_IPV4) != 0) 1418 in6p->inp_ip_ttl = optval; 1419 } 1420 break; 1421 #define OPTSET(bit) \ 1422 do { \ 1423 INP_WLOCK(in6p); \ 1424 if (optval) \ 1425 in6p->inp_flags |= (bit); \ 1426 else \ 1427 in6p->inp_flags &= ~(bit); \ 1428 INP_WUNLOCK(in6p); \ 1429 } while (/*CONSTCOND*/ 0) 1430 #define OPTSET2292(bit) \ 1431 do { \ 1432 INP_WLOCK(in6p); \ 1433 in6p->inp_flags |= IN6P_RFC2292; \ 1434 if (optval) \ 1435 in6p->inp_flags |= (bit); \ 1436 else \ 1437 in6p->inp_flags &= ~(bit); \ 1438 INP_WUNLOCK(in6p); \ 1439 } while (/*CONSTCOND*/ 0) 1440 #define OPTBIT(bit) (in6p->inp_flags & (bit) ? 1 : 0) 1441 1442 case IPV6_RECVPKTINFO: 1443 /* cannot mix with RFC2292 */ 1444 if (OPTBIT(IN6P_RFC2292)) { 1445 error = EINVAL; 1446 break; 1447 } 1448 OPTSET(IN6P_PKTINFO); 1449 break; 1450 1451 case IPV6_HOPLIMIT: 1452 { 1453 struct ip6_pktopts **optp; 1454 1455 /* cannot mix with RFC2292 */ 1456 if (OPTBIT(IN6P_RFC2292)) { 1457 error = EINVAL; 1458 break; 1459 } 1460 optp = &in6p->in6p_outputopts; 1461 error = ip6_pcbopt(IPV6_HOPLIMIT, 1462 (u_char *)&optval, sizeof(optval), 1463 optp, (td != NULL) ? td->td_ucred : 1464 NULL, uproto); 1465 break; 1466 } 1467 1468 case IPV6_RECVHOPLIMIT: 1469 /* cannot mix with RFC2292 */ 1470 if (OPTBIT(IN6P_RFC2292)) { 1471 error = EINVAL; 1472 break; 1473 } 1474 OPTSET(IN6P_HOPLIMIT); 1475 break; 1476 1477 case IPV6_RECVHOPOPTS: 1478 /* cannot mix with RFC2292 */ 1479 if (OPTBIT(IN6P_RFC2292)) { 1480 error = EINVAL; 1481 break; 1482 } 1483 OPTSET(IN6P_HOPOPTS); 1484 break; 1485 1486 case IPV6_RECVDSTOPTS: 1487 /* cannot mix with RFC2292 */ 1488 if (OPTBIT(IN6P_RFC2292)) { 1489 error = EINVAL; 1490 break; 1491 } 1492 OPTSET(IN6P_DSTOPTS); 1493 break; 1494 1495 case IPV6_RECVRTHDRDSTOPTS: 1496 /* cannot mix with RFC2292 */ 1497 if (OPTBIT(IN6P_RFC2292)) { 1498 error = EINVAL; 1499 break; 1500 } 1501 OPTSET(IN6P_RTHDRDSTOPTS); 1502 break; 1503 1504 case IPV6_RECVRTHDR: 1505 /* cannot mix with RFC2292 */ 1506 if (OPTBIT(IN6P_RFC2292)) { 1507 error = EINVAL; 1508 break; 1509 } 1510 OPTSET(IN6P_RTHDR); 1511 break; 1512 1513 case IPV6_FAITH: 1514 OPTSET(INP_FAITH); 1515 break; 1516 1517 case IPV6_RECVPATHMTU: 1518 /* 1519 * We ignore this option for TCP 1520 * sockets. 1521 * (RFC3542 leaves this case 1522 * unspecified.) 1523 */ 1524 if (uproto != IPPROTO_TCP) 1525 OPTSET(IN6P_MTU); 1526 break; 1527 1528 case IPV6_V6ONLY: 1529 /* 1530 * make setsockopt(IPV6_V6ONLY) 1531 * available only prior to bind(2). 1532 * see ipng mailing list, Jun 22 2001. 1533 */ 1534 if (in6p->inp_lport || 1535 !IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr)) { 1536 error = EINVAL; 1537 break; 1538 } 1539 OPTSET(IN6P_IPV6_V6ONLY); 1540 if (optval) 1541 in6p->inp_vflag &= ~INP_IPV4; 1542 else 1543 in6p->inp_vflag |= INP_IPV4; 1544 break; 1545 case IPV6_RECVTCLASS: 1546 /* cannot mix with RFC2292 XXX */ 1547 if (OPTBIT(IN6P_RFC2292)) { 1548 error = EINVAL; 1549 break; 1550 } 1551 OPTSET(IN6P_TCLASS); 1552 break; 1553 case IPV6_AUTOFLOWLABEL: 1554 OPTSET(IN6P_AUTOFLOWLABEL); 1555 break; 1556 1557 case IPV6_BINDANY: 1558 OPTSET(INP_BINDANY); 1559 break; 1560 } 1561 break; 1562 1563 case IPV6_TCLASS: 1564 case IPV6_DONTFRAG: 1565 case IPV6_USE_MIN_MTU: 1566 case IPV6_PREFER_TEMPADDR: 1567 if (optlen != sizeof(optval)) { 1568 error = EINVAL; 1569 break; 1570 } 1571 error = sooptcopyin(sopt, &optval, 1572 sizeof optval, sizeof optval); 1573 if (error) 1574 break; 1575 { 1576 struct ip6_pktopts **optp; 1577 optp = &in6p->in6p_outputopts; 1578 error = ip6_pcbopt(optname, 1579 (u_char *)&optval, sizeof(optval), 1580 optp, (td != NULL) ? td->td_ucred : 1581 NULL, uproto); 1582 break; 1583 } 1584 1585 case IPV6_2292PKTINFO: 1586 case IPV6_2292HOPLIMIT: 1587 case IPV6_2292HOPOPTS: 1588 case IPV6_2292DSTOPTS: 1589 case IPV6_2292RTHDR: 1590 /* RFC 2292 */ 1591 if (optlen != sizeof(int)) { 1592 error = EINVAL; 1593 break; 1594 } 1595 error = sooptcopyin(sopt, &optval, 1596 sizeof optval, sizeof optval); 1597 if (error) 1598 break; 1599 switch (optname) { 1600 case IPV6_2292PKTINFO: 1601 OPTSET2292(IN6P_PKTINFO); 1602 break; 1603 case IPV6_2292HOPLIMIT: 1604 OPTSET2292(IN6P_HOPLIMIT); 1605 break; 1606 case IPV6_2292HOPOPTS: 1607 /* 1608 * Check super-user privilege. 1609 * See comments for IPV6_RECVHOPOPTS. 1610 */ 1611 if (td != NULL) { 1612 error = priv_check(td, 1613 PRIV_NETINET_SETHDROPTS); 1614 if (error) 1615 return (error); 1616 } 1617 OPTSET2292(IN6P_HOPOPTS); 1618 break; 1619 case IPV6_2292DSTOPTS: 1620 if (td != NULL) { 1621 error = priv_check(td, 1622 PRIV_NETINET_SETHDROPTS); 1623 if (error) 1624 return (error); 1625 } 1626 OPTSET2292(IN6P_DSTOPTS|IN6P_RTHDRDSTOPTS); /* XXX */ 1627 break; 1628 case IPV6_2292RTHDR: 1629 OPTSET2292(IN6P_RTHDR); 1630 break; 1631 } 1632 break; 1633 case IPV6_PKTINFO: 1634 case IPV6_HOPOPTS: 1635 case IPV6_RTHDR: 1636 case IPV6_DSTOPTS: 1637 case IPV6_RTHDRDSTOPTS: 1638 case IPV6_NEXTHOP: 1639 { 1640 /* new advanced API (RFC3542) */ 1641 u_char *optbuf; 1642 u_char optbuf_storage[MCLBYTES]; 1643 int optlen; 1644 struct ip6_pktopts **optp; 1645 1646 /* cannot mix with RFC2292 */ 1647 if (OPTBIT(IN6P_RFC2292)) { 1648 error = EINVAL; 1649 break; 1650 } 1651 1652 /* 1653 * We only ensure valsize is not too large 1654 * here. Further validation will be done 1655 * later. 1656 */ 1657 error = sooptcopyin(sopt, optbuf_storage, 1658 sizeof(optbuf_storage), 0); 1659 if (error) 1660 break; 1661 optlen = sopt->sopt_valsize; 1662 optbuf = optbuf_storage; 1663 optp = &in6p->in6p_outputopts; 1664 error = ip6_pcbopt(optname, optbuf, optlen, 1665 optp, (td != NULL) ? td->td_ucred : NULL, 1666 uproto); 1667 break; 1668 } 1669 #undef OPTSET 1670 1671 case IPV6_MULTICAST_IF: 1672 case IPV6_MULTICAST_HOPS: 1673 case IPV6_MULTICAST_LOOP: 1674 case IPV6_JOIN_GROUP: 1675 case IPV6_LEAVE_GROUP: 1676 case IPV6_MSFILTER: 1677 case MCAST_BLOCK_SOURCE: 1678 case MCAST_UNBLOCK_SOURCE: 1679 case MCAST_JOIN_GROUP: 1680 case MCAST_LEAVE_GROUP: 1681 case MCAST_JOIN_SOURCE_GROUP: 1682 case MCAST_LEAVE_SOURCE_GROUP: 1683 error = ip6_setmoptions(in6p, sopt); 1684 break; 1685 1686 case IPV6_PORTRANGE: 1687 error = sooptcopyin(sopt, &optval, 1688 sizeof optval, sizeof optval); 1689 if (error) 1690 break; 1691 1692 INP_WLOCK(in6p); 1693 switch (optval) { 1694 case IPV6_PORTRANGE_DEFAULT: 1695 in6p->inp_flags &= ~(INP_LOWPORT); 1696 in6p->inp_flags &= ~(INP_HIGHPORT); 1697 break; 1698 1699 case IPV6_PORTRANGE_HIGH: 1700 in6p->inp_flags &= ~(INP_LOWPORT); 1701 in6p->inp_flags |= INP_HIGHPORT; 1702 break; 1703 1704 case IPV6_PORTRANGE_LOW: 1705 in6p->inp_flags &= ~(INP_HIGHPORT); 1706 in6p->inp_flags |= INP_LOWPORT; 1707 break; 1708 1709 default: 1710 error = EINVAL; 1711 break; 1712 } 1713 INP_WUNLOCK(in6p); 1714 break; 1715 1716 #ifdef IPSEC 1717 case IPV6_IPSEC_POLICY: 1718 { 1719 caddr_t req; 1720 struct mbuf *m; 1721 1722 if ((error = soopt_getm(sopt, &m)) != 0) /* XXX */ 1723 break; 1724 if ((error = soopt_mcopyin(sopt, m)) != 0) /* XXX */ 1725 break; 1726 req = mtod(m, caddr_t); 1727 error = ipsec_set_policy(in6p, optname, req, 1728 m->m_len, (sopt->sopt_td != NULL) ? 1729 sopt->sopt_td->td_ucred : NULL); 1730 m_freem(m); 1731 break; 1732 } 1733 #endif /* IPSEC */ 1734 1735 default: 1736 error = ENOPROTOOPT; 1737 break; 1738 } 1739 break; 1740 1741 case SOPT_GET: 1742 switch (optname) { 1743 1744 case IPV6_2292PKTOPTIONS: 1745 #ifdef IPV6_PKTOPTIONS 1746 case IPV6_PKTOPTIONS: 1747 #endif 1748 /* 1749 * RFC3542 (effectively) deprecated the 1750 * semantics of the 2292-style pktoptions. 1751 * Since it was not reliable in nature (i.e., 1752 * applications had to expect the lack of some 1753 * information after all), it would make sense 1754 * to simplify this part by always returning 1755 * empty data. 1756 */ 1757 sopt->sopt_valsize = 0; 1758 break; 1759 1760 case IPV6_RECVHOPOPTS: 1761 case IPV6_RECVDSTOPTS: 1762 case IPV6_RECVRTHDRDSTOPTS: 1763 case IPV6_UNICAST_HOPS: 1764 case IPV6_RECVPKTINFO: 1765 case IPV6_RECVHOPLIMIT: 1766 case IPV6_RECVRTHDR: 1767 case IPV6_RECVPATHMTU: 1768 1769 case IPV6_FAITH: 1770 case IPV6_V6ONLY: 1771 case IPV6_PORTRANGE: 1772 case IPV6_RECVTCLASS: 1773 case IPV6_AUTOFLOWLABEL: 1774 case IPV6_BINDANY: 1775 switch (optname) { 1776 1777 case IPV6_RECVHOPOPTS: 1778 optval = OPTBIT(IN6P_HOPOPTS); 1779 break; 1780 1781 case IPV6_RECVDSTOPTS: 1782 optval = OPTBIT(IN6P_DSTOPTS); 1783 break; 1784 1785 case IPV6_RECVRTHDRDSTOPTS: 1786 optval = OPTBIT(IN6P_RTHDRDSTOPTS); 1787 break; 1788 1789 case IPV6_UNICAST_HOPS: 1790 optval = in6p->in6p_hops; 1791 break; 1792 1793 case IPV6_RECVPKTINFO: 1794 optval = OPTBIT(IN6P_PKTINFO); 1795 break; 1796 1797 case IPV6_RECVHOPLIMIT: 1798 optval = OPTBIT(IN6P_HOPLIMIT); 1799 break; 1800 1801 case IPV6_RECVRTHDR: 1802 optval = OPTBIT(IN6P_RTHDR); 1803 break; 1804 1805 case IPV6_RECVPATHMTU: 1806 optval = OPTBIT(IN6P_MTU); 1807 break; 1808 1809 case IPV6_FAITH: 1810 optval = OPTBIT(INP_FAITH); 1811 break; 1812 1813 case IPV6_V6ONLY: 1814 optval = OPTBIT(IN6P_IPV6_V6ONLY); 1815 break; 1816 1817 case IPV6_PORTRANGE: 1818 { 1819 int flags; 1820 flags = in6p->inp_flags; 1821 if (flags & INP_HIGHPORT) 1822 optval = IPV6_PORTRANGE_HIGH; 1823 else if (flags & INP_LOWPORT) 1824 optval = IPV6_PORTRANGE_LOW; 1825 else 1826 optval = 0; 1827 break; 1828 } 1829 case IPV6_RECVTCLASS: 1830 optval = OPTBIT(IN6P_TCLASS); 1831 break; 1832 1833 case IPV6_AUTOFLOWLABEL: 1834 optval = OPTBIT(IN6P_AUTOFLOWLABEL); 1835 break; 1836 1837 case IPV6_BINDANY: 1838 optval = OPTBIT(INP_BINDANY); 1839 break; 1840 } 1841 if (error) 1842 break; 1843 error = sooptcopyout(sopt, &optval, 1844 sizeof optval); 1845 break; 1846 1847 case IPV6_PATHMTU: 1848 { 1849 u_long pmtu = 0; 1850 struct ip6_mtuinfo mtuinfo; 1851 struct route_in6 sro; 1852 1853 bzero(&sro, sizeof(sro)); 1854 1855 if (!(so->so_state & SS_ISCONNECTED)) 1856 return (ENOTCONN); 1857 /* 1858 * XXX: we dot not consider the case of source 1859 * routing, or optional information to specify 1860 * the outgoing interface. 1861 */ 1862 error = ip6_getpmtu(&sro, NULL, NULL, 1863 &in6p->in6p_faddr, &pmtu, NULL, 1864 so->so_fibnum); 1865 if (sro.ro_rt) 1866 RTFREE(sro.ro_rt); 1867 if (error) 1868 break; 1869 if (pmtu > IPV6_MAXPACKET) 1870 pmtu = IPV6_MAXPACKET; 1871 1872 bzero(&mtuinfo, sizeof(mtuinfo)); 1873 mtuinfo.ip6m_mtu = (u_int32_t)pmtu; 1874 optdata = (void *)&mtuinfo; 1875 optdatalen = sizeof(mtuinfo); 1876 error = sooptcopyout(sopt, optdata, 1877 optdatalen); 1878 break; 1879 } 1880 1881 case IPV6_2292PKTINFO: 1882 case IPV6_2292HOPLIMIT: 1883 case IPV6_2292HOPOPTS: 1884 case IPV6_2292RTHDR: 1885 case IPV6_2292DSTOPTS: 1886 switch (optname) { 1887 case IPV6_2292PKTINFO: 1888 optval = OPTBIT(IN6P_PKTINFO); 1889 break; 1890 case IPV6_2292HOPLIMIT: 1891 optval = OPTBIT(IN6P_HOPLIMIT); 1892 break; 1893 case IPV6_2292HOPOPTS: 1894 optval = OPTBIT(IN6P_HOPOPTS); 1895 break; 1896 case IPV6_2292RTHDR: 1897 optval = OPTBIT(IN6P_RTHDR); 1898 break; 1899 case IPV6_2292DSTOPTS: 1900 optval = OPTBIT(IN6P_DSTOPTS|IN6P_RTHDRDSTOPTS); 1901 break; 1902 } 1903 error = sooptcopyout(sopt, &optval, 1904 sizeof optval); 1905 break; 1906 case IPV6_PKTINFO: 1907 case IPV6_HOPOPTS: 1908 case IPV6_RTHDR: 1909 case IPV6_DSTOPTS: 1910 case IPV6_RTHDRDSTOPTS: 1911 case IPV6_NEXTHOP: 1912 case IPV6_TCLASS: 1913 case IPV6_DONTFRAG: 1914 case IPV6_USE_MIN_MTU: 1915 case IPV6_PREFER_TEMPADDR: 1916 error = ip6_getpcbopt(in6p->in6p_outputopts, 1917 optname, sopt); 1918 break; 1919 1920 case IPV6_MULTICAST_IF: 1921 case IPV6_MULTICAST_HOPS: 1922 case IPV6_MULTICAST_LOOP: 1923 case IPV6_MSFILTER: 1924 error = ip6_getmoptions(in6p, sopt); 1925 break; 1926 1927 #ifdef IPSEC 1928 case IPV6_IPSEC_POLICY: 1929 { 1930 caddr_t req = NULL; 1931 size_t len = 0; 1932 struct mbuf *m = NULL; 1933 struct mbuf **mp = &m; 1934 size_t ovalsize = sopt->sopt_valsize; 1935 caddr_t oval = (caddr_t)sopt->sopt_val; 1936 1937 error = soopt_getm(sopt, &m); /* XXX */ 1938 if (error != 0) 1939 break; 1940 error = soopt_mcopyin(sopt, m); /* XXX */ 1941 if (error != 0) 1942 break; 1943 sopt->sopt_valsize = ovalsize; 1944 sopt->sopt_val = oval; 1945 if (m) { 1946 req = mtod(m, caddr_t); 1947 len = m->m_len; 1948 } 1949 error = ipsec_get_policy(in6p, req, len, mp); 1950 if (error == 0) 1951 error = soopt_mcopyout(sopt, m); /* XXX */ 1952 if (error == 0 && m) 1953 m_freem(m); 1954 break; 1955 } 1956 #endif /* IPSEC */ 1957 1958 default: 1959 error = ENOPROTOOPT; 1960 break; 1961 } 1962 break; 1963 } 1964 } 1965 return (error); 1966 } 1967 1968 int 1969 ip6_raw_ctloutput(struct socket *so, struct sockopt *sopt) 1970 { 1971 int error = 0, optval, optlen; 1972 const int icmp6off = offsetof(struct icmp6_hdr, icmp6_cksum); 1973 struct inpcb *in6p = sotoinpcb(so); 1974 int level, op, optname; 1975 1976 level = sopt->sopt_level; 1977 op = sopt->sopt_dir; 1978 optname = sopt->sopt_name; 1979 optlen = sopt->sopt_valsize; 1980 1981 if (level != IPPROTO_IPV6) { 1982 return (EINVAL); 1983 } 1984 1985 switch (optname) { 1986 case IPV6_CHECKSUM: 1987 /* 1988 * For ICMPv6 sockets, no modification allowed for checksum 1989 * offset, permit "no change" values to help existing apps. 1990 * 1991 * RFC3542 says: "An attempt to set IPV6_CHECKSUM 1992 * for an ICMPv6 socket will fail." 1993 * The current behavior does not meet RFC3542. 1994 */ 1995 switch (op) { 1996 case SOPT_SET: 1997 if (optlen != sizeof(int)) { 1998 error = EINVAL; 1999 break; 2000 } 2001 error = sooptcopyin(sopt, &optval, sizeof(optval), 2002 sizeof(optval)); 2003 if (error) 2004 break; 2005 if ((optval % 2) != 0) { 2006 /* the API assumes even offset values */ 2007 error = EINVAL; 2008 } else if (so->so_proto->pr_protocol == 2009 IPPROTO_ICMPV6) { 2010 if (optval != icmp6off) 2011 error = EINVAL; 2012 } else 2013 in6p->in6p_cksum = optval; 2014 break; 2015 2016 case SOPT_GET: 2017 if (so->so_proto->pr_protocol == IPPROTO_ICMPV6) 2018 optval = icmp6off; 2019 else 2020 optval = in6p->in6p_cksum; 2021 2022 error = sooptcopyout(sopt, &optval, sizeof(optval)); 2023 break; 2024 2025 default: 2026 error = EINVAL; 2027 break; 2028 } 2029 break; 2030 2031 default: 2032 error = ENOPROTOOPT; 2033 break; 2034 } 2035 2036 return (error); 2037 } 2038 2039 /* 2040 * Set up IP6 options in pcb for insertion in output packets or 2041 * specifying behavior of outgoing packets. 2042 */ 2043 static int 2044 ip6_pcbopts(struct ip6_pktopts **pktopt, struct mbuf *m, 2045 struct socket *so, struct sockopt *sopt) 2046 { 2047 struct ip6_pktopts *opt = *pktopt; 2048 int error = 0; 2049 struct thread *td = sopt->sopt_td; 2050 2051 /* turn off any old options. */ 2052 if (opt) { 2053 #ifdef DIAGNOSTIC 2054 if (opt->ip6po_pktinfo || opt->ip6po_nexthop || 2055 opt->ip6po_hbh || opt->ip6po_dest1 || opt->ip6po_dest2 || 2056 opt->ip6po_rhinfo.ip6po_rhi_rthdr) 2057 printf("ip6_pcbopts: all specified options are cleared.\n"); 2058 #endif 2059 ip6_clearpktopts(opt, -1); 2060 } else 2061 opt = malloc(sizeof(*opt), M_IP6OPT, M_WAITOK); 2062 *pktopt = NULL; 2063 2064 if (!m || m->m_len == 0) { 2065 /* 2066 * Only turning off any previous options, regardless of 2067 * whether the opt is just created or given. 2068 */ 2069 free(opt, M_IP6OPT); 2070 return (0); 2071 } 2072 2073 /* set options specified by user. */ 2074 if ((error = ip6_setpktopts(m, opt, NULL, (td != NULL) ? 2075 td->td_ucred : NULL, so->so_proto->pr_protocol)) != 0) { 2076 ip6_clearpktopts(opt, -1); /* XXX: discard all options */ 2077 free(opt, M_IP6OPT); 2078 return (error); 2079 } 2080 *pktopt = opt; 2081 return (0); 2082 } 2083 2084 /* 2085 * initialize ip6_pktopts. beware that there are non-zero default values in 2086 * the struct. 2087 */ 2088 void 2089 ip6_initpktopts(struct ip6_pktopts *opt) 2090 { 2091 2092 bzero(opt, sizeof(*opt)); 2093 opt->ip6po_hlim = -1; /* -1 means default hop limit */ 2094 opt->ip6po_tclass = -1; /* -1 means default traffic class */ 2095 opt->ip6po_minmtu = IP6PO_MINMTU_MCASTONLY; 2096 opt->ip6po_prefer_tempaddr = IP6PO_TEMPADDR_SYSTEM; 2097 } 2098 2099 static int 2100 ip6_pcbopt(int optname, u_char *buf, int len, struct ip6_pktopts **pktopt, 2101 struct ucred *cred, int uproto) 2102 { 2103 struct ip6_pktopts *opt; 2104 2105 if (*pktopt == NULL) { 2106 *pktopt = malloc(sizeof(struct ip6_pktopts), M_IP6OPT, 2107 M_WAITOK); 2108 ip6_initpktopts(*pktopt); 2109 } 2110 opt = *pktopt; 2111 2112 return (ip6_setpktopt(optname, buf, len, opt, cred, 1, 0, uproto)); 2113 } 2114 2115 static int 2116 ip6_getpcbopt(struct ip6_pktopts *pktopt, int optname, struct sockopt *sopt) 2117 { 2118 void *optdata = NULL; 2119 int optdatalen = 0; 2120 struct ip6_ext *ip6e; 2121 int error = 0; 2122 struct in6_pktinfo null_pktinfo; 2123 int deftclass = 0, on; 2124 int defminmtu = IP6PO_MINMTU_MCASTONLY; 2125 int defpreftemp = IP6PO_TEMPADDR_SYSTEM; 2126 2127 switch (optname) { 2128 case IPV6_PKTINFO: 2129 if (pktopt && pktopt->ip6po_pktinfo) 2130 optdata = (void *)pktopt->ip6po_pktinfo; 2131 else { 2132 /* XXX: we don't have to do this every time... */ 2133 bzero(&null_pktinfo, sizeof(null_pktinfo)); 2134 optdata = (void *)&null_pktinfo; 2135 } 2136 optdatalen = sizeof(struct in6_pktinfo); 2137 break; 2138 case IPV6_TCLASS: 2139 if (pktopt && pktopt->ip6po_tclass >= 0) 2140 optdata = (void *)&pktopt->ip6po_tclass; 2141 else 2142 optdata = (void *)&deftclass; 2143 optdatalen = sizeof(int); 2144 break; 2145 case IPV6_HOPOPTS: 2146 if (pktopt && pktopt->ip6po_hbh) { 2147 optdata = (void *)pktopt->ip6po_hbh; 2148 ip6e = (struct ip6_ext *)pktopt->ip6po_hbh; 2149 optdatalen = (ip6e->ip6e_len + 1) << 3; 2150 } 2151 break; 2152 case IPV6_RTHDR: 2153 if (pktopt && pktopt->ip6po_rthdr) { 2154 optdata = (void *)pktopt->ip6po_rthdr; 2155 ip6e = (struct ip6_ext *)pktopt->ip6po_rthdr; 2156 optdatalen = (ip6e->ip6e_len + 1) << 3; 2157 } 2158 break; 2159 case IPV6_RTHDRDSTOPTS: 2160 if (pktopt && pktopt->ip6po_dest1) { 2161 optdata = (void *)pktopt->ip6po_dest1; 2162 ip6e = (struct ip6_ext *)pktopt->ip6po_dest1; 2163 optdatalen = (ip6e->ip6e_len + 1) << 3; 2164 } 2165 break; 2166 case IPV6_DSTOPTS: 2167 if (pktopt && pktopt->ip6po_dest2) { 2168 optdata = (void *)pktopt->ip6po_dest2; 2169 ip6e = (struct ip6_ext *)pktopt->ip6po_dest2; 2170 optdatalen = (ip6e->ip6e_len + 1) << 3; 2171 } 2172 break; 2173 case IPV6_NEXTHOP: 2174 if (pktopt && pktopt->ip6po_nexthop) { 2175 optdata = (void *)pktopt->ip6po_nexthop; 2176 optdatalen = pktopt->ip6po_nexthop->sa_len; 2177 } 2178 break; 2179 case IPV6_USE_MIN_MTU: 2180 if (pktopt) 2181 optdata = (void *)&pktopt->ip6po_minmtu; 2182 else 2183 optdata = (void *)&defminmtu; 2184 optdatalen = sizeof(int); 2185 break; 2186 case IPV6_DONTFRAG: 2187 if (pktopt && ((pktopt->ip6po_flags) & IP6PO_DONTFRAG)) 2188 on = 1; 2189 else 2190 on = 0; 2191 optdata = (void *)&on; 2192 optdatalen = sizeof(on); 2193 break; 2194 case IPV6_PREFER_TEMPADDR: 2195 if (pktopt) 2196 optdata = (void *)&pktopt->ip6po_prefer_tempaddr; 2197 else 2198 optdata = (void *)&defpreftemp; 2199 optdatalen = sizeof(int); 2200 break; 2201 default: /* should not happen */ 2202 #ifdef DIAGNOSTIC 2203 panic("ip6_getpcbopt: unexpected option\n"); 2204 #endif 2205 return (ENOPROTOOPT); 2206 } 2207 2208 error = sooptcopyout(sopt, optdata, optdatalen); 2209 2210 return (error); 2211 } 2212 2213 void 2214 ip6_clearpktopts(struct ip6_pktopts *pktopt, int optname) 2215 { 2216 if (pktopt == NULL) 2217 return; 2218 2219 if (optname == -1 || optname == IPV6_PKTINFO) { 2220 if (pktopt->ip6po_pktinfo) 2221 free(pktopt->ip6po_pktinfo, M_IP6OPT); 2222 pktopt->ip6po_pktinfo = NULL; 2223 } 2224 if (optname == -1 || optname == IPV6_HOPLIMIT) 2225 pktopt->ip6po_hlim = -1; 2226 if (optname == -1 || optname == IPV6_TCLASS) 2227 pktopt->ip6po_tclass = -1; 2228 if (optname == -1 || optname == IPV6_NEXTHOP) { 2229 if (pktopt->ip6po_nextroute.ro_rt) { 2230 RTFREE(pktopt->ip6po_nextroute.ro_rt); 2231 pktopt->ip6po_nextroute.ro_rt = NULL; 2232 } 2233 if (pktopt->ip6po_nexthop) 2234 free(pktopt->ip6po_nexthop, M_IP6OPT); 2235 pktopt->ip6po_nexthop = NULL; 2236 } 2237 if (optname == -1 || optname == IPV6_HOPOPTS) { 2238 if (pktopt->ip6po_hbh) 2239 free(pktopt->ip6po_hbh, M_IP6OPT); 2240 pktopt->ip6po_hbh = NULL; 2241 } 2242 if (optname == -1 || optname == IPV6_RTHDRDSTOPTS) { 2243 if (pktopt->ip6po_dest1) 2244 free(pktopt->ip6po_dest1, M_IP6OPT); 2245 pktopt->ip6po_dest1 = NULL; 2246 } 2247 if (optname == -1 || optname == IPV6_RTHDR) { 2248 if (pktopt->ip6po_rhinfo.ip6po_rhi_rthdr) 2249 free(pktopt->ip6po_rhinfo.ip6po_rhi_rthdr, M_IP6OPT); 2250 pktopt->ip6po_rhinfo.ip6po_rhi_rthdr = NULL; 2251 if (pktopt->ip6po_route.ro_rt) { 2252 RTFREE(pktopt->ip6po_route.ro_rt); 2253 pktopt->ip6po_route.ro_rt = NULL; 2254 } 2255 } 2256 if (optname == -1 || optname == IPV6_DSTOPTS) { 2257 if (pktopt->ip6po_dest2) 2258 free(pktopt->ip6po_dest2, M_IP6OPT); 2259 pktopt->ip6po_dest2 = NULL; 2260 } 2261 } 2262 2263 #define PKTOPT_EXTHDRCPY(type) \ 2264 do {\ 2265 if (src->type) {\ 2266 int hlen = (((struct ip6_ext *)src->type)->ip6e_len + 1) << 3;\ 2267 dst->type = malloc(hlen, M_IP6OPT, canwait);\ 2268 if (dst->type == NULL && canwait == M_NOWAIT)\ 2269 goto bad;\ 2270 bcopy(src->type, dst->type, hlen);\ 2271 }\ 2272 } while (/*CONSTCOND*/ 0) 2273 2274 static int 2275 copypktopts(struct ip6_pktopts *dst, struct ip6_pktopts *src, int canwait) 2276 { 2277 if (dst == NULL || src == NULL) { 2278 printf("ip6_clearpktopts: invalid argument\n"); 2279 return (EINVAL); 2280 } 2281 2282 dst->ip6po_hlim = src->ip6po_hlim; 2283 dst->ip6po_tclass = src->ip6po_tclass; 2284 dst->ip6po_flags = src->ip6po_flags; 2285 dst->ip6po_minmtu = src->ip6po_minmtu; 2286 dst->ip6po_prefer_tempaddr = src->ip6po_prefer_tempaddr; 2287 if (src->ip6po_pktinfo) { 2288 dst->ip6po_pktinfo = malloc(sizeof(*dst->ip6po_pktinfo), 2289 M_IP6OPT, canwait); 2290 if (dst->ip6po_pktinfo == NULL) 2291 goto bad; 2292 *dst->ip6po_pktinfo = *src->ip6po_pktinfo; 2293 } 2294 if (src->ip6po_nexthop) { 2295 dst->ip6po_nexthop = malloc(src->ip6po_nexthop->sa_len, 2296 M_IP6OPT, canwait); 2297 if (dst->ip6po_nexthop == NULL) 2298 goto bad; 2299 bcopy(src->ip6po_nexthop, dst->ip6po_nexthop, 2300 src->ip6po_nexthop->sa_len); 2301 } 2302 PKTOPT_EXTHDRCPY(ip6po_hbh); 2303 PKTOPT_EXTHDRCPY(ip6po_dest1); 2304 PKTOPT_EXTHDRCPY(ip6po_dest2); 2305 PKTOPT_EXTHDRCPY(ip6po_rthdr); /* not copy the cached route */ 2306 return (0); 2307 2308 bad: 2309 ip6_clearpktopts(dst, -1); 2310 return (ENOBUFS); 2311 } 2312 #undef PKTOPT_EXTHDRCPY 2313 2314 struct ip6_pktopts * 2315 ip6_copypktopts(struct ip6_pktopts *src, int canwait) 2316 { 2317 int error; 2318 struct ip6_pktopts *dst; 2319 2320 dst = malloc(sizeof(*dst), M_IP6OPT, canwait); 2321 if (dst == NULL) 2322 return (NULL); 2323 ip6_initpktopts(dst); 2324 2325 if ((error = copypktopts(dst, src, canwait)) != 0) { 2326 free(dst, M_IP6OPT); 2327 return (NULL); 2328 } 2329 2330 return (dst); 2331 } 2332 2333 void 2334 ip6_freepcbopts(struct ip6_pktopts *pktopt) 2335 { 2336 if (pktopt == NULL) 2337 return; 2338 2339 ip6_clearpktopts(pktopt, -1); 2340 2341 free(pktopt, M_IP6OPT); 2342 } 2343 2344 /* 2345 * Set IPv6 outgoing packet options based on advanced API. 2346 */ 2347 int 2348 ip6_setpktopts(struct mbuf *control, struct ip6_pktopts *opt, 2349 struct ip6_pktopts *stickyopt, struct ucred *cred, int uproto) 2350 { 2351 struct cmsghdr *cm = 0; 2352 2353 if (control == NULL || opt == NULL) 2354 return (EINVAL); 2355 2356 ip6_initpktopts(opt); 2357 if (stickyopt) { 2358 int error; 2359 2360 /* 2361 * If stickyopt is provided, make a local copy of the options 2362 * for this particular packet, then override them by ancillary 2363 * objects. 2364 * XXX: copypktopts() does not copy the cached route to a next 2365 * hop (if any). This is not very good in terms of efficiency, 2366 * but we can allow this since this option should be rarely 2367 * used. 2368 */ 2369 if ((error = copypktopts(opt, stickyopt, M_NOWAIT)) != 0) 2370 return (error); 2371 } 2372 2373 /* 2374 * XXX: Currently, we assume all the optional information is stored 2375 * in a single mbuf. 2376 */ 2377 if (control->m_next) 2378 return (EINVAL); 2379 2380 for (; control->m_len > 0; control->m_data += CMSG_ALIGN(cm->cmsg_len), 2381 control->m_len -= CMSG_ALIGN(cm->cmsg_len)) { 2382 int error; 2383 2384 if (control->m_len < CMSG_LEN(0)) 2385 return (EINVAL); 2386 2387 cm = mtod(control, struct cmsghdr *); 2388 if (cm->cmsg_len == 0 || cm->cmsg_len > control->m_len) 2389 return (EINVAL); 2390 if (cm->cmsg_level != IPPROTO_IPV6) 2391 continue; 2392 2393 error = ip6_setpktopt(cm->cmsg_type, CMSG_DATA(cm), 2394 cm->cmsg_len - CMSG_LEN(0), opt, cred, 0, 1, uproto); 2395 if (error) 2396 return (error); 2397 } 2398 2399 return (0); 2400 } 2401 2402 /* 2403 * Set a particular packet option, as a sticky option or an ancillary data 2404 * item. "len" can be 0 only when it's a sticky option. 2405 * We have 4 cases of combination of "sticky" and "cmsg": 2406 * "sticky=0, cmsg=0": impossible 2407 * "sticky=0, cmsg=1": RFC2292 or RFC3542 ancillary data 2408 * "sticky=1, cmsg=0": RFC3542 socket option 2409 * "sticky=1, cmsg=1": RFC2292 socket option 2410 */ 2411 static int 2412 ip6_setpktopt(int optname, u_char *buf, int len, struct ip6_pktopts *opt, 2413 struct ucred *cred, int sticky, int cmsg, int uproto) 2414 { 2415 int minmtupolicy, preftemp; 2416 int error; 2417 2418 if (!sticky && !cmsg) { 2419 #ifdef DIAGNOSTIC 2420 printf("ip6_setpktopt: impossible case\n"); 2421 #endif 2422 return (EINVAL); 2423 } 2424 2425 /* 2426 * IPV6_2292xxx is for backward compatibility to RFC2292, and should 2427 * not be specified in the context of RFC3542. Conversely, 2428 * RFC3542 types should not be specified in the context of RFC2292. 2429 */ 2430 if (!cmsg) { 2431 switch (optname) { 2432 case IPV6_2292PKTINFO: 2433 case IPV6_2292HOPLIMIT: 2434 case IPV6_2292NEXTHOP: 2435 case IPV6_2292HOPOPTS: 2436 case IPV6_2292DSTOPTS: 2437 case IPV6_2292RTHDR: 2438 case IPV6_2292PKTOPTIONS: 2439 return (ENOPROTOOPT); 2440 } 2441 } 2442 if (sticky && cmsg) { 2443 switch (optname) { 2444 case IPV6_PKTINFO: 2445 case IPV6_HOPLIMIT: 2446 case IPV6_NEXTHOP: 2447 case IPV6_HOPOPTS: 2448 case IPV6_DSTOPTS: 2449 case IPV6_RTHDRDSTOPTS: 2450 case IPV6_RTHDR: 2451 case IPV6_USE_MIN_MTU: 2452 case IPV6_DONTFRAG: 2453 case IPV6_TCLASS: 2454 case IPV6_PREFER_TEMPADDR: /* XXX: not an RFC3542 option */ 2455 return (ENOPROTOOPT); 2456 } 2457 } 2458 2459 switch (optname) { 2460 case IPV6_2292PKTINFO: 2461 case IPV6_PKTINFO: 2462 { 2463 struct ifnet *ifp = NULL; 2464 struct in6_pktinfo *pktinfo; 2465 2466 if (len != sizeof(struct in6_pktinfo)) 2467 return (EINVAL); 2468 2469 pktinfo = (struct in6_pktinfo *)buf; 2470 2471 /* 2472 * An application can clear any sticky IPV6_PKTINFO option by 2473 * doing a "regular" setsockopt with ipi6_addr being 2474 * in6addr_any and ipi6_ifindex being zero. 2475 * [RFC 3542, Section 6] 2476 */ 2477 if (optname == IPV6_PKTINFO && opt->ip6po_pktinfo && 2478 pktinfo->ipi6_ifindex == 0 && 2479 IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) { 2480 ip6_clearpktopts(opt, optname); 2481 break; 2482 } 2483 2484 if (uproto == IPPROTO_TCP && optname == IPV6_PKTINFO && 2485 sticky && !IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) { 2486 return (EINVAL); 2487 } 2488 2489 /* validate the interface index if specified. */ 2490 if (pktinfo->ipi6_ifindex > V_if_index) 2491 return (ENXIO); 2492 if (pktinfo->ipi6_ifindex) { 2493 ifp = ifnet_byindex(pktinfo->ipi6_ifindex); 2494 if (ifp == NULL) 2495 return (ENXIO); 2496 } 2497 2498 /* 2499 * We store the address anyway, and let in6_selectsrc() 2500 * validate the specified address. This is because ipi6_addr 2501 * may not have enough information about its scope zone, and 2502 * we may need additional information (such as outgoing 2503 * interface or the scope zone of a destination address) to 2504 * disambiguate the scope. 2505 * XXX: the delay of the validation may confuse the 2506 * application when it is used as a sticky option. 2507 */ 2508 if (opt->ip6po_pktinfo == NULL) { 2509 opt->ip6po_pktinfo = malloc(sizeof(*pktinfo), 2510 M_IP6OPT, M_NOWAIT); 2511 if (opt->ip6po_pktinfo == NULL) 2512 return (ENOBUFS); 2513 } 2514 bcopy(pktinfo, opt->ip6po_pktinfo, sizeof(*pktinfo)); 2515 break; 2516 } 2517 2518 case IPV6_2292HOPLIMIT: 2519 case IPV6_HOPLIMIT: 2520 { 2521 int *hlimp; 2522 2523 /* 2524 * RFC 3542 deprecated the usage of sticky IPV6_HOPLIMIT 2525 * to simplify the ordering among hoplimit options. 2526 */ 2527 if (optname == IPV6_HOPLIMIT && sticky) 2528 return (ENOPROTOOPT); 2529 2530 if (len != sizeof(int)) 2531 return (EINVAL); 2532 hlimp = (int *)buf; 2533 if (*hlimp < -1 || *hlimp > 255) 2534 return (EINVAL); 2535 2536 opt->ip6po_hlim = *hlimp; 2537 break; 2538 } 2539 2540 case IPV6_TCLASS: 2541 { 2542 int tclass; 2543 2544 if (len != sizeof(int)) 2545 return (EINVAL); 2546 tclass = *(int *)buf; 2547 if (tclass < -1 || tclass > 255) 2548 return (EINVAL); 2549 2550 opt->ip6po_tclass = tclass; 2551 break; 2552 } 2553 2554 case IPV6_2292NEXTHOP: 2555 case IPV6_NEXTHOP: 2556 if (cred != NULL) { 2557 error = priv_check_cred(cred, 2558 PRIV_NETINET_SETHDROPTS, 0); 2559 if (error) 2560 return (error); 2561 } 2562 2563 if (len == 0) { /* just remove the option */ 2564 ip6_clearpktopts(opt, IPV6_NEXTHOP); 2565 break; 2566 } 2567 2568 /* check if cmsg_len is large enough for sa_len */ 2569 if (len < sizeof(struct sockaddr) || len < *buf) 2570 return (EINVAL); 2571 2572 switch (((struct sockaddr *)buf)->sa_family) { 2573 case AF_INET6: 2574 { 2575 struct sockaddr_in6 *sa6 = (struct sockaddr_in6 *)buf; 2576 int error; 2577 2578 if (sa6->sin6_len != sizeof(struct sockaddr_in6)) 2579 return (EINVAL); 2580 2581 if (IN6_IS_ADDR_UNSPECIFIED(&sa6->sin6_addr) || 2582 IN6_IS_ADDR_MULTICAST(&sa6->sin6_addr)) { 2583 return (EINVAL); 2584 } 2585 if ((error = sa6_embedscope(sa6, V_ip6_use_defzone)) 2586 != 0) { 2587 return (error); 2588 } 2589 break; 2590 } 2591 case AF_LINK: /* should eventually be supported */ 2592 default: 2593 return (EAFNOSUPPORT); 2594 } 2595 2596 /* turn off the previous option, then set the new option. */ 2597 ip6_clearpktopts(opt, IPV6_NEXTHOP); 2598 opt->ip6po_nexthop = malloc(*buf, M_IP6OPT, M_NOWAIT); 2599 if (opt->ip6po_nexthop == NULL) 2600 return (ENOBUFS); 2601 bcopy(buf, opt->ip6po_nexthop, *buf); 2602 break; 2603 2604 case IPV6_2292HOPOPTS: 2605 case IPV6_HOPOPTS: 2606 { 2607 struct ip6_hbh *hbh; 2608 int hbhlen; 2609 2610 /* 2611 * XXX: We don't allow a non-privileged user to set ANY HbH 2612 * options, since per-option restriction has too much 2613 * overhead. 2614 */ 2615 if (cred != NULL) { 2616 error = priv_check_cred(cred, 2617 PRIV_NETINET_SETHDROPTS, 0); 2618 if (error) 2619 return (error); 2620 } 2621 2622 if (len == 0) { 2623 ip6_clearpktopts(opt, IPV6_HOPOPTS); 2624 break; /* just remove the option */ 2625 } 2626 2627 /* message length validation */ 2628 if (len < sizeof(struct ip6_hbh)) 2629 return (EINVAL); 2630 hbh = (struct ip6_hbh *)buf; 2631 hbhlen = (hbh->ip6h_len + 1) << 3; 2632 if (len != hbhlen) 2633 return (EINVAL); 2634 2635 /* turn off the previous option, then set the new option. */ 2636 ip6_clearpktopts(opt, IPV6_HOPOPTS); 2637 opt->ip6po_hbh = malloc(hbhlen, M_IP6OPT, M_NOWAIT); 2638 if (opt->ip6po_hbh == NULL) 2639 return (ENOBUFS); 2640 bcopy(hbh, opt->ip6po_hbh, hbhlen); 2641 2642 break; 2643 } 2644 2645 case IPV6_2292DSTOPTS: 2646 case IPV6_DSTOPTS: 2647 case IPV6_RTHDRDSTOPTS: 2648 { 2649 struct ip6_dest *dest, **newdest = NULL; 2650 int destlen; 2651 2652 if (cred != NULL) { /* XXX: see the comment for IPV6_HOPOPTS */ 2653 error = priv_check_cred(cred, 2654 PRIV_NETINET_SETHDROPTS, 0); 2655 if (error) 2656 return (error); 2657 } 2658 2659 if (len == 0) { 2660 ip6_clearpktopts(opt, optname); 2661 break; /* just remove the option */ 2662 } 2663 2664 /* message length validation */ 2665 if (len < sizeof(struct ip6_dest)) 2666 return (EINVAL); 2667 dest = (struct ip6_dest *)buf; 2668 destlen = (dest->ip6d_len + 1) << 3; 2669 if (len != destlen) 2670 return (EINVAL); 2671 2672 /* 2673 * Determine the position that the destination options header 2674 * should be inserted; before or after the routing header. 2675 */ 2676 switch (optname) { 2677 case IPV6_2292DSTOPTS: 2678 /* 2679 * The old advacned API is ambiguous on this point. 2680 * Our approach is to determine the position based 2681 * according to the existence of a routing header. 2682 * Note, however, that this depends on the order of the 2683 * extension headers in the ancillary data; the 1st 2684 * part of the destination options header must appear 2685 * before the routing header in the ancillary data, 2686 * too. 2687 * RFC3542 solved the ambiguity by introducing 2688 * separate ancillary data or option types. 2689 */ 2690 if (opt->ip6po_rthdr == NULL) 2691 newdest = &opt->ip6po_dest1; 2692 else 2693 newdest = &opt->ip6po_dest2; 2694 break; 2695 case IPV6_RTHDRDSTOPTS: 2696 newdest = &opt->ip6po_dest1; 2697 break; 2698 case IPV6_DSTOPTS: 2699 newdest = &opt->ip6po_dest2; 2700 break; 2701 } 2702 2703 /* turn off the previous option, then set the new option. */ 2704 ip6_clearpktopts(opt, optname); 2705 *newdest = malloc(destlen, M_IP6OPT, M_NOWAIT); 2706 if (*newdest == NULL) 2707 return (ENOBUFS); 2708 bcopy(dest, *newdest, destlen); 2709 2710 break; 2711 } 2712 2713 case IPV6_2292RTHDR: 2714 case IPV6_RTHDR: 2715 { 2716 struct ip6_rthdr *rth; 2717 int rthlen; 2718 2719 if (len == 0) { 2720 ip6_clearpktopts(opt, IPV6_RTHDR); 2721 break; /* just remove the option */ 2722 } 2723 2724 /* message length validation */ 2725 if (len < sizeof(struct ip6_rthdr)) 2726 return (EINVAL); 2727 rth = (struct ip6_rthdr *)buf; 2728 rthlen = (rth->ip6r_len + 1) << 3; 2729 if (len != rthlen) 2730 return (EINVAL); 2731 2732 switch (rth->ip6r_type) { 2733 case IPV6_RTHDR_TYPE_0: 2734 if (rth->ip6r_len == 0) /* must contain one addr */ 2735 return (EINVAL); 2736 if (rth->ip6r_len % 2) /* length must be even */ 2737 return (EINVAL); 2738 if (rth->ip6r_len / 2 != rth->ip6r_segleft) 2739 return (EINVAL); 2740 break; 2741 default: 2742 return (EINVAL); /* not supported */ 2743 } 2744 2745 /* turn off the previous option */ 2746 ip6_clearpktopts(opt, IPV6_RTHDR); 2747 opt->ip6po_rthdr = malloc(rthlen, M_IP6OPT, M_NOWAIT); 2748 if (opt->ip6po_rthdr == NULL) 2749 return (ENOBUFS); 2750 bcopy(rth, opt->ip6po_rthdr, rthlen); 2751 2752 break; 2753 } 2754 2755 case IPV6_USE_MIN_MTU: 2756 if (len != sizeof(int)) 2757 return (EINVAL); 2758 minmtupolicy = *(int *)buf; 2759 if (minmtupolicy != IP6PO_MINMTU_MCASTONLY && 2760 minmtupolicy != IP6PO_MINMTU_DISABLE && 2761 minmtupolicy != IP6PO_MINMTU_ALL) { 2762 return (EINVAL); 2763 } 2764 opt->ip6po_minmtu = minmtupolicy; 2765 break; 2766 2767 case IPV6_DONTFRAG: 2768 if (len != sizeof(int)) 2769 return (EINVAL); 2770 2771 if (uproto == IPPROTO_TCP || *(int *)buf == 0) { 2772 /* 2773 * we ignore this option for TCP sockets. 2774 * (RFC3542 leaves this case unspecified.) 2775 */ 2776 opt->ip6po_flags &= ~IP6PO_DONTFRAG; 2777 } else 2778 opt->ip6po_flags |= IP6PO_DONTFRAG; 2779 break; 2780 2781 case IPV6_PREFER_TEMPADDR: 2782 if (len != sizeof(int)) 2783 return (EINVAL); 2784 preftemp = *(int *)buf; 2785 if (preftemp != IP6PO_TEMPADDR_SYSTEM && 2786 preftemp != IP6PO_TEMPADDR_NOTPREFER && 2787 preftemp != IP6PO_TEMPADDR_PREFER) { 2788 return (EINVAL); 2789 } 2790 opt->ip6po_prefer_tempaddr = preftemp; 2791 break; 2792 2793 default: 2794 return (ENOPROTOOPT); 2795 } /* end of switch */ 2796 2797 return (0); 2798 } 2799 2800 /* 2801 * Routine called from ip6_output() to loop back a copy of an IP6 multicast 2802 * packet to the input queue of a specified interface. Note that this 2803 * calls the output routine of the loopback "driver", but with an interface 2804 * pointer that might NOT be &loif -- easier than replicating that code here. 2805 */ 2806 void 2807 ip6_mloopback(struct ifnet *ifp, struct mbuf *m, struct sockaddr_in6 *dst) 2808 { 2809 struct mbuf *copym; 2810 struct ip6_hdr *ip6; 2811 2812 copym = m_copy(m, 0, M_COPYALL); 2813 if (copym == NULL) 2814 return; 2815 2816 /* 2817 * Make sure to deep-copy IPv6 header portion in case the data 2818 * is in an mbuf cluster, so that we can safely override the IPv6 2819 * header portion later. 2820 */ 2821 if ((copym->m_flags & M_EXT) != 0 || 2822 copym->m_len < sizeof(struct ip6_hdr)) { 2823 copym = m_pullup(copym, sizeof(struct ip6_hdr)); 2824 if (copym == NULL) 2825 return; 2826 } 2827 2828 #ifdef DIAGNOSTIC 2829 if (copym->m_len < sizeof(*ip6)) { 2830 m_freem(copym); 2831 return; 2832 } 2833 #endif 2834 2835 ip6 = mtod(copym, struct ip6_hdr *); 2836 /* 2837 * clear embedded scope identifiers if necessary. 2838 * in6_clearscope will touch the addresses only when necessary. 2839 */ 2840 in6_clearscope(&ip6->ip6_src); 2841 in6_clearscope(&ip6->ip6_dst); 2842 2843 (void)if_simloop(ifp, copym, dst->sin6_family, 0); 2844 } 2845 2846 /* 2847 * Chop IPv6 header off from the payload. 2848 */ 2849 static int 2850 ip6_splithdr(struct mbuf *m, struct ip6_exthdrs *exthdrs) 2851 { 2852 struct mbuf *mh; 2853 struct ip6_hdr *ip6; 2854 2855 ip6 = mtod(m, struct ip6_hdr *); 2856 if (m->m_len > sizeof(*ip6)) { 2857 mh = m_gethdr(M_NOWAIT, MT_DATA); 2858 if (mh == NULL) { 2859 m_freem(m); 2860 return ENOBUFS; 2861 } 2862 m_move_pkthdr(mh, m); 2863 MH_ALIGN(mh, sizeof(*ip6)); 2864 m->m_len -= sizeof(*ip6); 2865 m->m_data += sizeof(*ip6); 2866 mh->m_next = m; 2867 m = mh; 2868 m->m_len = sizeof(*ip6); 2869 bcopy((caddr_t)ip6, mtod(m, caddr_t), sizeof(*ip6)); 2870 } 2871 exthdrs->ip6e_ip6 = m; 2872 return 0; 2873 } 2874 2875 /* 2876 * Compute IPv6 extension header length. 2877 */ 2878 int 2879 ip6_optlen(struct inpcb *in6p) 2880 { 2881 int len; 2882 2883 if (!in6p->in6p_outputopts) 2884 return 0; 2885 2886 len = 0; 2887 #define elen(x) \ 2888 (((struct ip6_ext *)(x)) ? (((struct ip6_ext *)(x))->ip6e_len + 1) << 3 : 0) 2889 2890 len += elen(in6p->in6p_outputopts->ip6po_hbh); 2891 if (in6p->in6p_outputopts->ip6po_rthdr) 2892 /* dest1 is valid with rthdr only */ 2893 len += elen(in6p->in6p_outputopts->ip6po_dest1); 2894 len += elen(in6p->in6p_outputopts->ip6po_rthdr); 2895 len += elen(in6p->in6p_outputopts->ip6po_dest2); 2896 return len; 2897 #undef elen 2898 } 2899