1 /* 2 * Copyright (c) 1982, 1986, 1988, 1990, 1993 3 * The Regents of the University of California. 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 University 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 REGENTS 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 REGENTS 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 * @(#)ip_output.c 8.3 (Berkeley) 1/21/94 30 * $FreeBSD: src/sys/netinet/ip_output.c,v 1.99.2.37 2003/04/15 06:44:45 silby Exp $ 31 * $DragonFly: src/sys/netinet/ip_output.c,v 1.32 2005/08/15 16:46:21 dillon Exp $ 32 */ 33 34 #define _IP_VHL 35 36 #include "opt_ipfw.h" 37 #include "opt_ipdn.h" 38 #include "opt_ipdivert.h" 39 #include "opt_ipfilter.h" 40 #include "opt_ipsec.h" 41 #include "opt_mbuf_stress_test.h" 42 43 #include <sys/param.h> 44 #include <sys/systm.h> 45 #include <sys/kernel.h> 46 #include <sys/malloc.h> 47 #include <sys/mbuf.h> 48 #include <sys/protosw.h> 49 #include <sys/socket.h> 50 #include <sys/socketvar.h> 51 #include <sys/proc.h> 52 #include <sys/sysctl.h> 53 #include <sys/thread2.h> 54 #include <sys/in_cksum.h> 55 56 #include <net/if.h> 57 #include <net/netisr.h> 58 #include <net/pfil.h> 59 #include <net/route.h> 60 61 #include <netinet/in.h> 62 #include <netinet/in_systm.h> 63 #include <netinet/ip.h> 64 #include <netinet/in_pcb.h> 65 #include <netinet/in_var.h> 66 #include <netinet/ip_var.h> 67 68 static MALLOC_DEFINE(M_IPMOPTS, "ip_moptions", "internet multicast options"); 69 70 #ifdef IPSEC 71 #include <netinet6/ipsec.h> 72 #include <netproto/key/key.h> 73 #ifdef IPSEC_DEBUG 74 #include <netproto/key/key_debug.h> 75 #else 76 #define KEYDEBUG(lev,arg) 77 #endif 78 #endif /*IPSEC*/ 79 80 #ifdef FAST_IPSEC 81 #include <netproto/ipsec/ipsec.h> 82 #include <netproto/ipsec/xform.h> 83 #include <netproto/ipsec/key.h> 84 #endif /*FAST_IPSEC*/ 85 86 #include <net/ipfw/ip_fw.h> 87 #include <net/dummynet/ip_dummynet.h> 88 89 #define print_ip(x, a, y) printf("%s %d.%d.%d.%d%s",\ 90 x, (ntohl(a.s_addr)>>24)&0xFF,\ 91 (ntohl(a.s_addr)>>16)&0xFF,\ 92 (ntohl(a.s_addr)>>8)&0xFF,\ 93 (ntohl(a.s_addr))&0xFF, y); 94 95 u_short ip_id; 96 97 #ifdef MBUF_STRESS_TEST 98 int mbuf_frag_size = 0; 99 SYSCTL_INT(_net_inet_ip, OID_AUTO, mbuf_frag_size, CTLFLAG_RW, 100 &mbuf_frag_size, 0, "Fragment outgoing mbufs to this size"); 101 #endif 102 103 static struct mbuf *ip_insertoptions(struct mbuf *, struct mbuf *, int *); 104 static struct ifnet *ip_multicast_if(struct in_addr *, int *); 105 static void ip_mloopback 106 (struct ifnet *, struct mbuf *, struct sockaddr_in *, int); 107 static int ip_getmoptions 108 (struct sockopt *, struct ip_moptions *); 109 static int ip_pcbopts(int, struct mbuf **, struct mbuf *); 110 static int ip_setmoptions 111 (struct sockopt *, struct ip_moptions **); 112 113 int ip_optcopy(struct ip *, struct ip *); 114 115 116 extern struct protosw inetsw[]; 117 118 /* 119 * IP output. The packet in mbuf chain m contains a skeletal IP 120 * header (with len, off, ttl, proto, tos, src, dst). 121 * The mbuf chain containing the packet will be freed. 122 * The mbuf opt, if present, will not be freed. 123 */ 124 int 125 ip_output(struct mbuf *m0, struct mbuf *opt, struct route *ro, 126 int flags, struct ip_moptions *imo, struct inpcb *inp) 127 { 128 struct ip *ip; 129 struct ifnet *ifp = NULL; /* keep compiler happy */ 130 struct mbuf *m; 131 int hlen = sizeof(struct ip); 132 int len, off, error = 0; 133 struct sockaddr_in *dst = NULL; /* keep compiler happy */ 134 struct in_ifaddr *ia = NULL; 135 int isbroadcast, sw_csum; 136 struct in_addr pkt_dst; 137 struct route iproute; 138 #ifdef IPSEC 139 struct secpolicy *sp = NULL; 140 struct socket *so = inp ? inp->inp_socket : NULL; 141 #endif 142 #ifdef FAST_IPSEC 143 struct m_tag *mtag; 144 struct secpolicy *sp = NULL; 145 struct tdb_ident *tdbi; 146 #endif /* FAST_IPSEC */ 147 struct ip_fw_args args; 148 int src_was_INADDR_ANY = 0; /* as the name says... */ 149 150 args.eh = NULL; 151 args.rule = NULL; 152 args.next_hop = NULL; 153 154 /* Grab info from MT_TAG mbufs prepended to the chain. */ 155 while (m0 != NULL && m0->m_type == MT_TAG) { 156 switch(m0->_m_tag_id) { 157 case PACKET_TAG_DUMMYNET: 158 /* 159 * the packet was already tagged, so part of the 160 * processing was already done, and we need to go down. 161 * Get parameters from the header. 162 */ 163 args.rule = ((struct dn_pkt *)m0)->rule; 164 opt = NULL ; 165 ro = &((struct dn_pkt *)m0)->ro; 166 imo = NULL ; 167 dst = ((struct dn_pkt *)m0)->dn_dst ; 168 ifp = ((struct dn_pkt *)m0)->ifp ; 169 flags = ((struct dn_pkt *)m0)->flags ; 170 break; 171 case PACKET_TAG_IPFORWARD: 172 args.next_hop = (struct sockaddr_in *)m0->m_data; 173 break; 174 default: 175 printf("ip_output: unrecognised MT_TAG tag %d\n", 176 m0->_m_tag_id); 177 break; 178 } 179 m0 = m0->m_next; 180 } 181 m = m0; 182 KASSERT(m != NULL && (m->m_flags & M_PKTHDR), ("ip_output: no HDR")); 183 184 if (ro == NULL) { 185 ro = &iproute; 186 bzero(ro, sizeof *ro); 187 } 188 189 if (args.rule != NULL) { /* dummynet already saw us */ 190 ip = mtod(m, struct ip *); 191 hlen = IP_VHL_HL(ip->ip_vhl) << 2 ; 192 if (ro->ro_rt) 193 ia = ifatoia(ro->ro_rt->rt_ifa); 194 goto sendit; 195 } 196 197 if (opt) { 198 len = 0; 199 m = ip_insertoptions(m, opt, &len); 200 if (len != 0) 201 hlen = len; 202 } 203 ip = mtod(m, struct ip *); 204 pkt_dst = args.next_hop ? args.next_hop->sin_addr : ip->ip_dst; 205 206 /* 207 * Fill in IP header. 208 */ 209 if (!(flags & (IP_FORWARDING|IP_RAWOUTPUT))) { 210 ip->ip_vhl = IP_MAKE_VHL(IPVERSION, hlen >> 2); 211 ip->ip_off &= IP_DF; 212 ip->ip_id = ip_newid(); 213 ipstat.ips_localout++; 214 } else { 215 hlen = IP_VHL_HL(ip->ip_vhl) << 2; 216 } 217 218 dst = (struct sockaddr_in *)&ro->ro_dst; 219 /* 220 * If there is a cached route, 221 * check that it is to the same destination 222 * and is still up. If not, free it and try again. 223 * The address family should also be checked in case of sharing the 224 * cache with IPv6. 225 */ 226 if (ro->ro_rt && 227 (!(ro->ro_rt->rt_flags & RTF_UP) || 228 dst->sin_family != AF_INET || 229 dst->sin_addr.s_addr != pkt_dst.s_addr)) { 230 rtfree(ro->ro_rt); 231 ro->ro_rt = (struct rtentry *)NULL; 232 } 233 if (ro->ro_rt == NULL) { 234 bzero(dst, sizeof *dst); 235 dst->sin_family = AF_INET; 236 dst->sin_len = sizeof *dst; 237 dst->sin_addr = pkt_dst; 238 } 239 /* 240 * If routing to interface only, 241 * short circuit routing lookup. 242 */ 243 if (flags & IP_ROUTETOIF) { 244 if ((ia = ifatoia(ifa_ifwithdstaddr(sintosa(dst)))) == NULL && 245 (ia = ifatoia(ifa_ifwithnet(sintosa(dst)))) == NULL) { 246 ipstat.ips_noroute++; 247 error = ENETUNREACH; 248 goto bad; 249 } 250 ifp = ia->ia_ifp; 251 ip->ip_ttl = 1; 252 isbroadcast = in_broadcast(dst->sin_addr, ifp); 253 } else if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) && 254 imo != NULL && imo->imo_multicast_ifp != NULL) { 255 /* 256 * Bypass the normal routing lookup for multicast 257 * packets if the interface is specified. 258 */ 259 ifp = imo->imo_multicast_ifp; 260 IFP_TO_IA(ifp, ia); 261 isbroadcast = 0; /* fool gcc */ 262 } else { 263 /* 264 * If this is the case, we probably don't want to allocate 265 * a protocol-cloned route since we didn't get one from the 266 * ULP. This lets TCP do its thing, while not burdening 267 * forwarding or ICMP with the overhead of cloning a route. 268 * Of course, we still want to do any cloning requested by 269 * the link layer, as this is probably required in all cases 270 * for correct operation (as it is for ARP). 271 */ 272 if (ro->ro_rt == NULL) 273 rtalloc_ign(ro, RTF_PRCLONING); 274 if (ro->ro_rt == NULL) { 275 ipstat.ips_noroute++; 276 error = EHOSTUNREACH; 277 goto bad; 278 } 279 ia = ifatoia(ro->ro_rt->rt_ifa); 280 ifp = ro->ro_rt->rt_ifp; 281 ro->ro_rt->rt_use++; 282 if (ro->ro_rt->rt_flags & RTF_GATEWAY) 283 dst = (struct sockaddr_in *)ro->ro_rt->rt_gateway; 284 if (ro->ro_rt->rt_flags & RTF_HOST) 285 isbroadcast = (ro->ro_rt->rt_flags & RTF_BROADCAST); 286 else 287 isbroadcast = in_broadcast(dst->sin_addr, ifp); 288 } 289 if (IN_MULTICAST(ntohl(pkt_dst.s_addr))) { 290 struct in_multi *inm; 291 292 m->m_flags |= M_MCAST; 293 /* 294 * IP destination address is multicast. Make sure "dst" 295 * still points to the address in "ro". (It may have been 296 * changed to point to a gateway address, above.) 297 */ 298 dst = (struct sockaddr_in *)&ro->ro_dst; 299 /* 300 * See if the caller provided any multicast options 301 */ 302 if (imo != NULL) { 303 ip->ip_ttl = imo->imo_multicast_ttl; 304 if (imo->imo_multicast_vif != -1) 305 ip->ip_src.s_addr = 306 ip_mcast_src ? 307 ip_mcast_src(imo->imo_multicast_vif) : 308 INADDR_ANY; 309 } else 310 ip->ip_ttl = IP_DEFAULT_MULTICAST_TTL; 311 /* 312 * Confirm that the outgoing interface supports multicast. 313 */ 314 if ((imo == NULL) || (imo->imo_multicast_vif == -1)) { 315 if (!(ifp->if_flags & IFF_MULTICAST)) { 316 ipstat.ips_noroute++; 317 error = ENETUNREACH; 318 goto bad; 319 } 320 } 321 /* 322 * If source address not specified yet, use address 323 * of outgoing interface. 324 */ 325 if (ip->ip_src.s_addr == INADDR_ANY) { 326 /* Interface may have no addresses. */ 327 if (ia != NULL) 328 ip->ip_src = IA_SIN(ia)->sin_addr; 329 } 330 331 IN_LOOKUP_MULTI(pkt_dst, ifp, inm); 332 if (inm != NULL && 333 (imo == NULL || imo->imo_multicast_loop)) { 334 /* 335 * If we belong to the destination multicast group 336 * on the outgoing interface, and the caller did not 337 * forbid loopback, loop back a copy. 338 */ 339 ip_mloopback(ifp, m, dst, hlen); 340 } 341 else { 342 /* 343 * If we are acting as a multicast router, perform 344 * multicast forwarding as if the packet had just 345 * arrived on the interface to which we are about 346 * to send. The multicast forwarding function 347 * recursively calls this function, using the 348 * IP_FORWARDING flag to prevent infinite recursion. 349 * 350 * Multicasts that are looped back by ip_mloopback(), 351 * above, will be forwarded by the ip_input() routine, 352 * if necessary. 353 */ 354 if (ip_mrouter && !(flags & IP_FORWARDING)) { 355 /* 356 * If rsvp daemon is not running, do not 357 * set ip_moptions. This ensures that the packet 358 * is multicast and not just sent down one link 359 * as prescribed by rsvpd. 360 */ 361 if (!rsvp_on) 362 imo = NULL; 363 if (ip_mforward && 364 ip_mforward(ip, ifp, m, imo) != 0) { 365 m_freem(m); 366 goto done; 367 } 368 } 369 } 370 371 /* 372 * Multicasts with a time-to-live of zero may be looped- 373 * back, above, but must not be transmitted on a network. 374 * Also, multicasts addressed to the loopback interface 375 * are not sent -- the above call to ip_mloopback() will 376 * loop back a copy if this host actually belongs to the 377 * destination group on the loopback interface. 378 */ 379 if (ip->ip_ttl == 0 || ifp->if_flags & IFF_LOOPBACK) { 380 m_freem(m); 381 goto done; 382 } 383 384 goto sendit; 385 } 386 #ifndef notdef 387 /* 388 * If the source address is not specified yet, use the address 389 * of the outoing interface. In case, keep note we did that, so 390 * if the the firewall changes the next-hop causing the output 391 * interface to change, we can fix that. 392 */ 393 if (ip->ip_src.s_addr == INADDR_ANY) { 394 /* Interface may have no addresses. */ 395 if (ia != NULL) { 396 ip->ip_src = IA_SIN(ia)->sin_addr; 397 src_was_INADDR_ANY = 1; 398 } 399 } 400 #endif /* notdef */ 401 #ifdef ALTQ 402 /* 403 * Disable packet drop hack. 404 * Packetdrop should be done by queueing. 405 */ 406 #else /* !ALTQ */ 407 /* 408 * Verify that we have any chance at all of being able to queue 409 * the packet or packet fragments 410 */ 411 if ((ifp->if_snd.ifq_len + ip->ip_len / ifp->if_mtu + 1) >= 412 ifp->if_snd.ifq_maxlen) { 413 error = ENOBUFS; 414 ipstat.ips_odropped++; 415 goto bad; 416 } 417 #endif /* !ALTQ */ 418 419 /* 420 * Look for broadcast address and 421 * verify user is allowed to send 422 * such a packet. 423 */ 424 if (isbroadcast) { 425 if (!(ifp->if_flags & IFF_BROADCAST)) { 426 error = EADDRNOTAVAIL; 427 goto bad; 428 } 429 if (!(flags & IP_ALLOWBROADCAST)) { 430 error = EACCES; 431 goto bad; 432 } 433 /* don't allow broadcast messages to be fragmented */ 434 if (ip->ip_len > ifp->if_mtu) { 435 error = EMSGSIZE; 436 goto bad; 437 } 438 m->m_flags |= M_BCAST; 439 } else { 440 m->m_flags &= ~M_BCAST; 441 } 442 443 sendit: 444 #ifdef IPSEC 445 /* get SP for this packet */ 446 if (so == NULL) 447 sp = ipsec4_getpolicybyaddr(m, IPSEC_DIR_OUTBOUND, flags, &error); 448 else 449 sp = ipsec4_getpolicybysock(m, IPSEC_DIR_OUTBOUND, so, &error); 450 451 if (sp == NULL) { 452 ipsecstat.out_inval++; 453 goto bad; 454 } 455 456 error = 0; 457 458 /* check policy */ 459 switch (sp->policy) { 460 case IPSEC_POLICY_DISCARD: 461 /* 462 * This packet is just discarded. 463 */ 464 ipsecstat.out_polvio++; 465 goto bad; 466 467 case IPSEC_POLICY_BYPASS: 468 case IPSEC_POLICY_NONE: 469 /* no need to do IPsec. */ 470 goto skip_ipsec; 471 472 case IPSEC_POLICY_IPSEC: 473 if (sp->req == NULL) { 474 /* acquire a policy */ 475 error = key_spdacquire(sp); 476 goto bad; 477 } 478 break; 479 480 case IPSEC_POLICY_ENTRUST: 481 default: 482 printf("ip_output: Invalid policy found. %d\n", sp->policy); 483 } 484 { 485 struct ipsec_output_state state; 486 bzero(&state, sizeof state); 487 state.m = m; 488 if (flags & IP_ROUTETOIF) { 489 state.ro = &iproute; 490 bzero(&iproute, sizeof iproute); 491 } else 492 state.ro = ro; 493 state.dst = (struct sockaddr *)dst; 494 495 ip->ip_sum = 0; 496 497 /* 498 * XXX 499 * delayed checksums are not currently compatible with IPsec 500 */ 501 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) { 502 in_delayed_cksum(m); 503 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA; 504 } 505 506 ip->ip_len = htons(ip->ip_len); 507 ip->ip_off = htons(ip->ip_off); 508 509 error = ipsec4_output(&state, sp, flags); 510 511 m = state.m; 512 if (flags & IP_ROUTETOIF) { 513 /* 514 * if we have tunnel mode SA, we may need to ignore 515 * IP_ROUTETOIF. 516 */ 517 if (state.ro != &iproute || state.ro->ro_rt != NULL) { 518 flags &= ~IP_ROUTETOIF; 519 ro = state.ro; 520 } 521 } else 522 ro = state.ro; 523 dst = (struct sockaddr_in *)state.dst; 524 if (error) { 525 /* mbuf is already reclaimed in ipsec4_output. */ 526 m0 = NULL; 527 switch (error) { 528 case EHOSTUNREACH: 529 case ENETUNREACH: 530 case EMSGSIZE: 531 case ENOBUFS: 532 case ENOMEM: 533 break; 534 default: 535 printf("ip4_output (ipsec): error code %d\n", error); 536 /*fall through*/ 537 case ENOENT: 538 /* don't show these error codes to the user */ 539 error = 0; 540 break; 541 } 542 goto bad; 543 } 544 } 545 546 /* be sure to update variables that are affected by ipsec4_output() */ 547 ip = mtod(m, struct ip *); 548 #ifdef _IP_VHL 549 hlen = IP_VHL_HL(ip->ip_vhl) << 2; 550 #else 551 hlen = ip->ip_hl << 2; 552 #endif 553 if (ro->ro_rt == NULL) { 554 if (!(flags & IP_ROUTETOIF)) { 555 printf("ip_output: " 556 "can't update route after IPsec processing\n"); 557 error = EHOSTUNREACH; /*XXX*/ 558 goto bad; 559 } 560 } else { 561 ia = ifatoia(ro->ro_rt->rt_ifa); 562 ifp = ro->ro_rt->rt_ifp; 563 } 564 565 /* make it flipped, again. */ 566 ip->ip_len = ntohs(ip->ip_len); 567 ip->ip_off = ntohs(ip->ip_off); 568 skip_ipsec: 569 #endif /*IPSEC*/ 570 #ifdef FAST_IPSEC 571 /* 572 * Check the security policy (SP) for the packet and, if 573 * required, do IPsec-related processing. There are two 574 * cases here; the first time a packet is sent through 575 * it will be untagged and handled by ipsec4_checkpolicy. 576 * If the packet is resubmitted to ip_output (e.g. after 577 * AH, ESP, etc. processing), there will be a tag to bypass 578 * the lookup and related policy checking. 579 */ 580 mtag = m_tag_find(m, PACKET_TAG_IPSEC_PENDING_TDB, NULL); 581 crit_enter(); 582 if (mtag != NULL) { 583 tdbi = (struct tdb_ident *)m_tag_data(mtag); 584 sp = ipsec_getpolicy(tdbi, IPSEC_DIR_OUTBOUND); 585 if (sp == NULL) 586 error = -EINVAL; /* force silent drop */ 587 m_tag_delete(m, mtag); 588 } else { 589 sp = ipsec4_checkpolicy(m, IPSEC_DIR_OUTBOUND, flags, 590 &error, inp); 591 } 592 /* 593 * There are four return cases: 594 * sp != NULL apply IPsec policy 595 * sp == NULL, error == 0 no IPsec handling needed 596 * sp == NULL, error == -EINVAL discard packet w/o error 597 * sp == NULL, error != 0 discard packet, report error 598 */ 599 if (sp != NULL) { 600 /* Loop detection, check if ipsec processing already done */ 601 KASSERT(sp->req != NULL, ("ip_output: no ipsec request")); 602 for (mtag = m_tag_first(m); mtag != NULL; 603 mtag = m_tag_next(m, mtag)) { 604 if (mtag->m_tag_cookie != MTAG_ABI_COMPAT) 605 continue; 606 if (mtag->m_tag_id != PACKET_TAG_IPSEC_OUT_DONE && 607 mtag->m_tag_id != PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED) 608 continue; 609 /* 610 * Check if policy has an SA associated with it. 611 * This can happen when an SP has yet to acquire 612 * an SA; e.g. on first reference. If it occurs, 613 * then we let ipsec4_process_packet do its thing. 614 */ 615 if (sp->req->sav == NULL) 616 break; 617 tdbi = (struct tdb_ident *)m_tag_data(mtag); 618 if (tdbi->spi == sp->req->sav->spi && 619 tdbi->proto == sp->req->sav->sah->saidx.proto && 620 bcmp(&tdbi->dst, &sp->req->sav->sah->saidx.dst, 621 sizeof(union sockaddr_union)) == 0) { 622 /* 623 * No IPsec processing is needed, free 624 * reference to SP. 625 * 626 * NB: null pointer to avoid free at 627 * done: below. 628 */ 629 KEY_FREESP(&sp), sp = NULL; 630 crit_exit(); 631 goto spd_done; 632 } 633 } 634 635 /* 636 * Do delayed checksums now because we send before 637 * this is done in the normal processing path. 638 */ 639 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) { 640 in_delayed_cksum(m); 641 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA; 642 } 643 644 ip->ip_len = htons(ip->ip_len); 645 ip->ip_off = htons(ip->ip_off); 646 647 /* NB: callee frees mbuf */ 648 error = ipsec4_process_packet(m, sp->req, flags, 0); 649 /* 650 * Preserve KAME behaviour: ENOENT can be returned 651 * when an SA acquire is in progress. Don't propagate 652 * this to user-level; it confuses applications. 653 * 654 * XXX this will go away when the SADB is redone. 655 */ 656 if (error == ENOENT) 657 error = 0; 658 crit_exit(); 659 goto done; 660 } else { 661 crit_exit(); 662 663 if (error != 0) { 664 /* 665 * Hack: -EINVAL is used to signal that a packet 666 * should be silently discarded. This is typically 667 * because we asked key management for an SA and 668 * it was delayed (e.g. kicked up to IKE). 669 */ 670 if (error == -EINVAL) 671 error = 0; 672 goto bad; 673 } else { 674 /* No IPsec processing for this packet. */ 675 } 676 #ifdef notyet 677 /* 678 * If deferred crypto processing is needed, check that 679 * the interface supports it. 680 */ 681 mtag = m_tag_find(m, PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED, NULL); 682 if (mtag != NULL && !(ifp->if_capenable & IFCAP_IPSEC)) { 683 /* notify IPsec to do its own crypto */ 684 ipsp_skipcrypto_unmark((struct tdb_ident *)m_tag_data(mtag)); 685 error = EHOSTUNREACH; 686 goto bad; 687 } 688 #endif 689 } 690 spd_done: 691 #endif /* FAST_IPSEC */ 692 /* 693 * IpHack's section. 694 * - Xlate: translate packet's addr/port (NAT). 695 * - Firewall: deny/allow/etc. 696 * - Wrap: fake packet's addr/port <unimpl.> 697 * - Encapsulate: put it in another IP and send out. <unimp.> 698 */ 699 700 /* 701 * Run through list of hooks for output packets. 702 */ 703 if (pfil_has_hooks(&inet_pfil_hook)) { 704 error = pfil_run_hooks(&inet_pfil_hook, &m, ifp, PFIL_OUT); 705 if (error != 0 || m == NULL) 706 goto done; 707 ip = mtod(m, struct ip *); 708 } 709 710 /* 711 * Check with the firewall... 712 * but not if we are already being fwd'd from a firewall. 713 */ 714 if (fw_enable && IPFW_LOADED && !args.next_hop) { 715 struct sockaddr_in *old = dst; 716 717 args.m = m; 718 args.next_hop = dst; 719 args.oif = ifp; 720 off = ip_fw_chk_ptr(&args); 721 m = args.m; 722 dst = args.next_hop; 723 724 /* 725 * On return we must do the following: 726 * m == NULL -> drop the pkt (old interface, deprecated) 727 * (off & IP_FW_PORT_DENY_FLAG) -> drop the pkt (new interface) 728 * 1<=off<= 0xffff -> DIVERT 729 * (off & IP_FW_PORT_DYNT_FLAG) -> send to a DUMMYNET pipe 730 * (off & IP_FW_PORT_TEE_FLAG) -> TEE the packet 731 * dst != old -> IPFIREWALL_FORWARD 732 * off==0, dst==old -> accept 733 * If some of the above modules are not compiled in, then 734 * we should't have to check the corresponding condition 735 * (because the ipfw control socket should not accept 736 * unsupported rules), but better play safe and drop 737 * packets in case of doubt. 738 */ 739 if ( (off & IP_FW_PORT_DENY_FLAG) || m == NULL) { 740 if (m) 741 m_freem(m); 742 error = EACCES; 743 goto done; 744 } 745 ip = mtod(m, struct ip *); 746 if (off == 0 && dst == old) /* common case */ 747 goto pass; 748 if (DUMMYNET_LOADED && (off & IP_FW_PORT_DYNT_FLAG)) { 749 /* 750 * pass the pkt to dummynet. Need to include 751 * pipe number, m, ifp, ro, dst because these are 752 * not recomputed in the next pass. 753 * All other parameters have been already used and 754 * so they are not needed anymore. 755 * XXX note: if the ifp or ro entry are deleted 756 * while a pkt is in dummynet, we are in trouble! 757 */ 758 args.ro = ro; 759 args.dst = dst; 760 args.flags = flags; 761 762 error = ip_dn_io_ptr(m, off & 0xffff, DN_TO_IP_OUT, 763 &args); 764 goto done; 765 } 766 #ifdef IPDIVERT 767 if (off != 0 && !(off & IP_FW_PORT_DYNT_FLAG)) { 768 struct mbuf *clone = NULL; 769 770 /* Clone packet if we're doing a 'tee' */ 771 if ((off & IP_FW_PORT_TEE_FLAG)) 772 clone = m_dup(m, MB_DONTWAIT); 773 774 /* 775 * XXX 776 * delayed checksums are not currently compatible 777 * with divert sockets. 778 */ 779 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) { 780 in_delayed_cksum(m); 781 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA; 782 } 783 784 /* Restore packet header fields to original values */ 785 ip->ip_len = htons(ip->ip_len); 786 ip->ip_off = htons(ip->ip_off); 787 788 /* Deliver packet to divert input routine */ 789 divert_packet(m, 0, off & 0xffff); 790 791 /* If 'tee', continue with original packet */ 792 if (clone != NULL) { 793 m = clone; 794 ip = mtod(m, struct ip *); 795 goto pass; 796 } 797 goto done; 798 } 799 #endif 800 801 /* IPFIREWALL_FORWARD */ 802 /* 803 * Check dst to make sure it is directly reachable on the 804 * interface we previously thought it was. 805 * If it isn't (which may be likely in some situations) we have 806 * to re-route it (ie, find a route for the next-hop and the 807 * associated interface) and set them here. This is nested 808 * forwarding which in most cases is undesirable, except where 809 * such control is nigh impossible. So we do it here. 810 * And I'm babbling. 811 */ 812 if (off == 0 && old != dst) { /* FORWARD, dst has changed */ 813 #if 0 814 /* 815 * XXX To improve readability, this block should be 816 * changed into a function call as below: 817 */ 818 error = ip_ipforward(&m, &dst, &ifp); 819 if (error) 820 goto bad; 821 if (m == NULL) /* ip_input consumed the mbuf */ 822 goto done; 823 #else 824 struct in_ifaddr *ia; 825 826 /* 827 * XXX sro_fwd below is static, and a pointer 828 * to it gets passed to routines downstream. 829 * This could have surprisingly bad results in 830 * practice, because its content is overwritten 831 * by subsequent packets. 832 */ 833 /* There must be a better way to do this next line... */ 834 static struct route sro_fwd; 835 struct route *ro_fwd = &sro_fwd; 836 837 #if 0 838 print_ip("IPFIREWALL_FORWARD: New dst ip: ", 839 dst->sin_addr, "\n"); 840 #endif 841 842 /* 843 * We need to figure out if we have been forwarded 844 * to a local socket. If so, then we should somehow 845 * "loop back" to ip_input, and get directed to the 846 * PCB as if we had received this packet. This is 847 * because it may be dificult to identify the packets 848 * you want to forward until they are being output 849 * and have selected an interface. (e.g. locally 850 * initiated packets) If we used the loopback inteface, 851 * we would not be able to control what happens 852 * as the packet runs through ip_input() as 853 * it is done through a ISR. 854 */ 855 LIST_FOREACH(ia, INADDR_HASH(dst->sin_addr.s_addr), 856 ia_hash) { 857 /* 858 * If the addr to forward to is one 859 * of ours, we pretend to 860 * be the destination for this packet. 861 */ 862 if (IA_SIN(ia)->sin_addr.s_addr == 863 dst->sin_addr.s_addr) 864 break; 865 } 866 if (ia != NULL) { /* tell ip_input "dont filter" */ 867 struct m_hdr tag; 868 869 tag.mh_type = MT_TAG; 870 tag.mh_flags = PACKET_TAG_IPFORWARD; 871 tag.mh_data = (caddr_t)args.next_hop; 872 tag.mh_next = m; 873 874 if (m->m_pkthdr.rcvif == NULL) 875 m->m_pkthdr.rcvif = ifunit("lo0"); 876 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) { 877 m->m_pkthdr.csum_flags |= 878 CSUM_DATA_VALID | CSUM_PSEUDO_HDR; 879 m0->m_pkthdr.csum_data = 0xffff; 880 } 881 m->m_pkthdr.csum_flags |= 882 CSUM_IP_CHECKED | CSUM_IP_VALID; 883 ip->ip_len = htons(ip->ip_len); 884 ip->ip_off = htons(ip->ip_off); 885 ip_input((struct mbuf *)&tag); 886 goto done; 887 } 888 /* Some of the logic for this was nicked from above. 889 * 890 * This rewrites the cached route in a local PCB. 891 * Is this what we want to do? 892 */ 893 bcopy(dst, &ro_fwd->ro_dst, sizeof *dst); 894 ro_fwd->ro_rt = NULL; 895 896 rtalloc_ign(ro_fwd, RTF_PRCLONING); 897 if (ro_fwd->ro_rt == NULL) { 898 ipstat.ips_noroute++; 899 error = EHOSTUNREACH; 900 goto bad; 901 } 902 903 ia = ifatoia(ro_fwd->ro_rt->rt_ifa); 904 ifp = ro_fwd->ro_rt->rt_ifp; 905 ro_fwd->ro_rt->rt_use++; 906 if (ro_fwd->ro_rt->rt_flags & RTF_GATEWAY) 907 dst = (struct sockaddr_in *) 908 ro_fwd->ro_rt->rt_gateway; 909 if (ro_fwd->ro_rt->rt_flags & RTF_HOST) 910 isbroadcast = 911 (ro_fwd->ro_rt->rt_flags & RTF_BROADCAST); 912 else 913 isbroadcast = in_broadcast(dst->sin_addr, ifp); 914 if (ro->ro_rt != NULL) 915 rtfree(ro->ro_rt); 916 ro->ro_rt = ro_fwd->ro_rt; 917 dst = (struct sockaddr_in *)&ro_fwd->ro_dst; 918 919 #endif /* ... block to be put into a function */ 920 /* 921 * If we added a default src ip earlier, 922 * which would have been gotten from the-then 923 * interface, do it again, from the new one. 924 */ 925 if (src_was_INADDR_ANY) 926 ip->ip_src = IA_SIN(ia)->sin_addr; 927 goto pass ; 928 } 929 930 /* 931 * if we get here, none of the above matches, and 932 * we have to drop the pkt 933 */ 934 m_freem(m); 935 error = EACCES; /* not sure this is the right error msg */ 936 goto done; 937 } 938 939 pass: 940 /* 127/8 must not appear on wire - RFC1122. */ 941 if ((ntohl(ip->ip_dst.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET || 942 (ntohl(ip->ip_src.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET) { 943 if (!(ifp->if_flags & IFF_LOOPBACK)) { 944 ipstat.ips_badaddr++; 945 error = EADDRNOTAVAIL; 946 goto bad; 947 } 948 } 949 950 m->m_pkthdr.csum_flags |= CSUM_IP; 951 sw_csum = m->m_pkthdr.csum_flags & ~ifp->if_hwassist; 952 if (sw_csum & CSUM_DELAY_DATA) { 953 in_delayed_cksum(m); 954 sw_csum &= ~CSUM_DELAY_DATA; 955 } 956 m->m_pkthdr.csum_flags &= ifp->if_hwassist; 957 958 /* 959 * If small enough for interface, or the interface will take 960 * care of the fragmentation for us, can just send directly. 961 */ 962 if (ip->ip_len <= ifp->if_mtu || ((ifp->if_hwassist & CSUM_FRAGMENT) && 963 !(ip->ip_off & IP_DF))) { 964 ip->ip_len = htons(ip->ip_len); 965 ip->ip_off = htons(ip->ip_off); 966 ip->ip_sum = 0; 967 if (sw_csum & CSUM_DELAY_IP) { 968 if (ip->ip_vhl == IP_VHL_BORING) { 969 ip->ip_sum = in_cksum_hdr(ip); 970 } else { 971 ip->ip_sum = in_cksum(m, hlen); 972 } 973 } 974 975 /* Record statistics for this interface address. */ 976 if (!(flags & IP_FORWARDING) && ia) { 977 ia->ia_ifa.if_opackets++; 978 ia->ia_ifa.if_obytes += m->m_pkthdr.len; 979 } 980 981 #ifdef IPSEC 982 /* clean ipsec history once it goes out of the node */ 983 ipsec_delaux(m); 984 #endif 985 986 #ifdef MBUF_STRESS_TEST 987 if (mbuf_frag_size && m->m_pkthdr.len > mbuf_frag_size) { 988 struct mbuf *m1, *m2; 989 int length, tmp; 990 991 tmp = length = m->m_pkthdr.len; 992 993 while ((length -= mbuf_frag_size) >= 1) { 994 m1 = m_split(m, length, MB_DONTWAIT); 995 if (m1 == NULL) 996 break; 997 m2 = m; 998 while (m2->m_next != NULL) 999 m2 = m2->m_next; 1000 m2->m_next = m1; 1001 } 1002 m->m_pkthdr.len = tmp; 1003 } 1004 #endif 1005 error = (*ifp->if_output)(ifp, m, (struct sockaddr *)dst, 1006 ro->ro_rt); 1007 goto done; 1008 } 1009 1010 if (ip->ip_off & IP_DF) { 1011 error = EMSGSIZE; 1012 /* 1013 * This case can happen if the user changed the MTU 1014 * of an interface after enabling IP on it. Because 1015 * most netifs don't keep track of routes pointing to 1016 * them, there is no way for one to update all its 1017 * routes when the MTU is changed. 1018 */ 1019 if ((ro->ro_rt->rt_flags & (RTF_UP | RTF_HOST)) && 1020 !(ro->ro_rt->rt_rmx.rmx_locks & RTV_MTU) && 1021 (ro->ro_rt->rt_rmx.rmx_mtu > ifp->if_mtu)) { 1022 ro->ro_rt->rt_rmx.rmx_mtu = ifp->if_mtu; 1023 } 1024 ipstat.ips_cantfrag++; 1025 goto bad; 1026 } 1027 1028 /* 1029 * Too large for interface; fragment if possible. If successful, 1030 * on return, m will point to a list of packets to be sent. 1031 */ 1032 error = ip_fragment(ip, &m, ifp->if_mtu, ifp->if_hwassist, sw_csum); 1033 if (error) 1034 goto bad; 1035 for (; m; m = m0) { 1036 m0 = m->m_nextpkt; 1037 m->m_nextpkt = NULL; 1038 #ifdef IPSEC 1039 /* clean ipsec history once it goes out of the node */ 1040 ipsec_delaux(m); 1041 #endif 1042 if (error == 0) { 1043 /* Record statistics for this interface address. */ 1044 if (ia != NULL) { 1045 ia->ia_ifa.if_opackets++; 1046 ia->ia_ifa.if_obytes += m->m_pkthdr.len; 1047 } 1048 error = (*ifp->if_output)(ifp, m, 1049 (struct sockaddr *)dst, 1050 ro->ro_rt); 1051 } else 1052 m_freem(m); 1053 } 1054 1055 if (error == 0) 1056 ipstat.ips_fragmented++; 1057 1058 done: 1059 if (ro == &iproute && ro->ro_rt != NULL) { 1060 RTFREE(ro->ro_rt); 1061 ro->ro_rt = NULL; 1062 } 1063 #ifdef IPSEC 1064 if (sp != NULL) { 1065 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 1066 printf("DP ip_output call free SP:%p\n", sp)); 1067 key_freesp(sp); 1068 } 1069 #endif 1070 #ifdef FAST_IPSEC 1071 if (sp != NULL) 1072 KEY_FREESP(&sp); 1073 #endif 1074 return (error); 1075 bad: 1076 m_freem(m); 1077 goto done; 1078 } 1079 1080 /* 1081 * Create a chain of fragments which fit the given mtu. m_frag points to the 1082 * mbuf to be fragmented; on return it points to the chain with the fragments. 1083 * Return 0 if no error. If error, m_frag may contain a partially built 1084 * chain of fragments that should be freed by the caller. 1085 * 1086 * if_hwassist_flags is the hw offload capabilities (see if_data.ifi_hwassist) 1087 * sw_csum contains the delayed checksums flags (e.g., CSUM_DELAY_IP). 1088 */ 1089 int 1090 ip_fragment(struct ip *ip, struct mbuf **m_frag, int mtu, 1091 u_long if_hwassist_flags, int sw_csum) 1092 { 1093 int error = 0; 1094 int hlen = IP_VHL_HL(ip->ip_vhl) << 2; 1095 int len = (mtu - hlen) & ~7; /* size of payload in each fragment */ 1096 int off; 1097 struct mbuf *m0 = *m_frag; /* the original packet */ 1098 int firstlen; 1099 struct mbuf **mnext; 1100 int nfrags; 1101 1102 if (ip->ip_off & IP_DF) { /* Fragmentation not allowed */ 1103 ipstat.ips_cantfrag++; 1104 return EMSGSIZE; 1105 } 1106 1107 /* 1108 * Must be able to put at least 8 bytes per fragment. 1109 */ 1110 if (len < 8) 1111 return EMSGSIZE; 1112 1113 /* 1114 * If the interface will not calculate checksums on 1115 * fragmented packets, then do it here. 1116 */ 1117 if ((m0->m_pkthdr.csum_flags & CSUM_DELAY_DATA) && 1118 !(if_hwassist_flags & CSUM_IP_FRAGS)) { 1119 in_delayed_cksum(m0); 1120 m0->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA; 1121 } 1122 1123 if (len > PAGE_SIZE) { 1124 /* 1125 * Fragment large datagrams such that each segment 1126 * contains a multiple of PAGE_SIZE amount of data, 1127 * plus headers. This enables a receiver to perform 1128 * page-flipping zero-copy optimizations. 1129 * 1130 * XXX When does this help given that sender and receiver 1131 * could have different page sizes, and also mtu could 1132 * be less than the receiver's page size ? 1133 */ 1134 int newlen; 1135 struct mbuf *m; 1136 1137 for (m = m0, off = 0; m && (off+m->m_len) <= mtu; m = m->m_next) 1138 off += m->m_len; 1139 1140 /* 1141 * firstlen (off - hlen) must be aligned on an 1142 * 8-byte boundary 1143 */ 1144 if (off < hlen) 1145 goto smart_frag_failure; 1146 off = ((off - hlen) & ~7) + hlen; 1147 newlen = (~PAGE_MASK) & mtu; 1148 if ((newlen + sizeof(struct ip)) > mtu) { 1149 /* we failed, go back the default */ 1150 smart_frag_failure: 1151 newlen = len; 1152 off = hlen + len; 1153 } 1154 len = newlen; 1155 1156 } else { 1157 off = hlen + len; 1158 } 1159 1160 firstlen = off - hlen; 1161 mnext = &m0->m_nextpkt; /* pointer to next packet */ 1162 1163 /* 1164 * Loop through length of segment after first fragment, 1165 * make new header and copy data of each part and link onto chain. 1166 * Here, m0 is the original packet, m is the fragment being created. 1167 * The fragments are linked off the m_nextpkt of the original 1168 * packet, which after processing serves as the first fragment. 1169 */ 1170 for (nfrags = 1; off < ip->ip_len; off += len, nfrags++) { 1171 struct ip *mhip; /* ip header on the fragment */ 1172 struct mbuf *m; 1173 int mhlen = sizeof(struct ip); 1174 1175 MGETHDR(m, MB_DONTWAIT, MT_HEADER); 1176 if (m == NULL) { 1177 error = ENOBUFS; 1178 ipstat.ips_odropped++; 1179 goto done; 1180 } 1181 m->m_flags |= (m0->m_flags & M_MCAST) | M_FRAG; 1182 /* 1183 * In the first mbuf, leave room for the link header, then 1184 * copy the original IP header including options. The payload 1185 * goes into an additional mbuf chain returned by m_copy(). 1186 */ 1187 m->m_data += max_linkhdr; 1188 mhip = mtod(m, struct ip *); 1189 *mhip = *ip; 1190 if (hlen > sizeof(struct ip)) { 1191 mhlen = ip_optcopy(ip, mhip) + sizeof(struct ip); 1192 mhip->ip_vhl = IP_MAKE_VHL(IPVERSION, mhlen >> 2); 1193 } 1194 m->m_len = mhlen; 1195 /* XXX do we need to add ip->ip_off below ? */ 1196 mhip->ip_off = ((off - hlen) >> 3) + ip->ip_off; 1197 if (off + len >= ip->ip_len) { /* last fragment */ 1198 len = ip->ip_len - off; 1199 m->m_flags |= M_LASTFRAG; 1200 } else 1201 mhip->ip_off |= IP_MF; 1202 mhip->ip_len = htons((u_short)(len + mhlen)); 1203 m->m_next = m_copy(m0, off, len); 1204 if (m->m_next == NULL) { /* copy failed */ 1205 m_free(m); 1206 error = ENOBUFS; /* ??? */ 1207 ipstat.ips_odropped++; 1208 goto done; 1209 } 1210 m->m_pkthdr.len = mhlen + len; 1211 m->m_pkthdr.rcvif = (struct ifnet *)NULL; 1212 m->m_pkthdr.csum_flags = m0->m_pkthdr.csum_flags; 1213 mhip->ip_off = htons(mhip->ip_off); 1214 mhip->ip_sum = 0; 1215 if (sw_csum & CSUM_DELAY_IP) 1216 mhip->ip_sum = in_cksum(m, mhlen); 1217 *mnext = m; 1218 mnext = &m->m_nextpkt; 1219 } 1220 ipstat.ips_ofragments += nfrags; 1221 1222 /* set first marker for fragment chain */ 1223 m0->m_flags |= M_FIRSTFRAG | M_FRAG; 1224 m0->m_pkthdr.csum_data = nfrags; 1225 1226 /* 1227 * Update first fragment by trimming what's been copied out 1228 * and updating header. 1229 */ 1230 m_adj(m0, hlen + firstlen - ip->ip_len); 1231 m0->m_pkthdr.len = hlen + firstlen; 1232 ip->ip_len = htons((u_short)m0->m_pkthdr.len); 1233 ip->ip_off |= IP_MF; 1234 ip->ip_off = htons(ip->ip_off); 1235 ip->ip_sum = 0; 1236 if (sw_csum & CSUM_DELAY_IP) 1237 ip->ip_sum = in_cksum(m0, hlen); 1238 1239 done: 1240 *m_frag = m0; 1241 return error; 1242 } 1243 1244 void 1245 in_delayed_cksum(struct mbuf *m) 1246 { 1247 struct ip *ip; 1248 u_short csum, offset; 1249 1250 ip = mtod(m, struct ip *); 1251 offset = IP_VHL_HL(ip->ip_vhl) << 2 ; 1252 csum = in_cksum_skip(m, ip->ip_len, offset); 1253 if (m->m_pkthdr.csum_flags & CSUM_UDP && csum == 0) 1254 csum = 0xffff; 1255 offset += m->m_pkthdr.csum_data; /* checksum offset */ 1256 1257 if (offset + sizeof(u_short) > m->m_len) { 1258 printf("delayed m_pullup, m->len: %d off: %d p: %d\n", 1259 m->m_len, offset, ip->ip_p); 1260 /* 1261 * XXX 1262 * this shouldn't happen, but if it does, the 1263 * correct behavior may be to insert the checksum 1264 * in the existing chain instead of rearranging it. 1265 */ 1266 m = m_pullup(m, offset + sizeof(u_short)); 1267 } 1268 *(u_short *)(m->m_data + offset) = csum; 1269 } 1270 1271 /* 1272 * Insert IP options into preformed packet. 1273 * Adjust IP destination as required for IP source routing, 1274 * as indicated by a non-zero in_addr at the start of the options. 1275 * 1276 * XXX This routine assumes that the packet has no options in place. 1277 */ 1278 static struct mbuf * 1279 ip_insertoptions(struct mbuf *m, struct mbuf *opt, int *phlen) 1280 { 1281 struct ipoption *p = mtod(opt, struct ipoption *); 1282 struct mbuf *n; 1283 struct ip *ip = mtod(m, struct ip *); 1284 unsigned optlen; 1285 1286 optlen = opt->m_len - sizeof p->ipopt_dst; 1287 if (optlen + (u_short)ip->ip_len > IP_MAXPACKET) { 1288 *phlen = 0; 1289 return (m); /* XXX should fail */ 1290 } 1291 if (p->ipopt_dst.s_addr) 1292 ip->ip_dst = p->ipopt_dst; 1293 if (m->m_flags & M_EXT || m->m_data - optlen < m->m_pktdat) { 1294 MGETHDR(n, MB_DONTWAIT, MT_HEADER); 1295 if (n == NULL) { 1296 *phlen = 0; 1297 return (m); 1298 } 1299 n->m_pkthdr.rcvif = (struct ifnet *)NULL; 1300 n->m_pkthdr.len = m->m_pkthdr.len + optlen; 1301 m->m_len -= sizeof(struct ip); 1302 m->m_data += sizeof(struct ip); 1303 n->m_next = m; 1304 m = n; 1305 m->m_len = optlen + sizeof(struct ip); 1306 m->m_data += max_linkhdr; 1307 memcpy(mtod(m, void *), ip, sizeof(struct ip)); 1308 } else { 1309 m->m_data -= optlen; 1310 m->m_len += optlen; 1311 m->m_pkthdr.len += optlen; 1312 ovbcopy(ip, mtod(m, caddr_t), sizeof(struct ip)); 1313 } 1314 ip = mtod(m, struct ip *); 1315 bcopy(p->ipopt_list, ip + 1, optlen); 1316 *phlen = sizeof(struct ip) + optlen; 1317 ip->ip_vhl = IP_MAKE_VHL(IPVERSION, *phlen >> 2); 1318 ip->ip_len += optlen; 1319 return (m); 1320 } 1321 1322 /* 1323 * Copy options from ip to jp, 1324 * omitting those not copied during fragmentation. 1325 */ 1326 int 1327 ip_optcopy(struct ip *ip, struct ip *jp) 1328 { 1329 u_char *cp, *dp; 1330 int opt, optlen, cnt; 1331 1332 cp = (u_char *)(ip + 1); 1333 dp = (u_char *)(jp + 1); 1334 cnt = (IP_VHL_HL(ip->ip_vhl) << 2) - sizeof(struct ip); 1335 for (; cnt > 0; cnt -= optlen, cp += optlen) { 1336 opt = cp[0]; 1337 if (opt == IPOPT_EOL) 1338 break; 1339 if (opt == IPOPT_NOP) { 1340 /* Preserve for IP mcast tunnel's LSRR alignment. */ 1341 *dp++ = IPOPT_NOP; 1342 optlen = 1; 1343 continue; 1344 } 1345 1346 KASSERT(cnt >= IPOPT_OLEN + sizeof *cp, 1347 ("ip_optcopy: malformed ipv4 option")); 1348 optlen = cp[IPOPT_OLEN]; 1349 KASSERT(optlen >= IPOPT_OLEN + sizeof *cp && optlen <= cnt, 1350 ("ip_optcopy: malformed ipv4 option")); 1351 1352 /* bogus lengths should have been caught by ip_dooptions */ 1353 if (optlen > cnt) 1354 optlen = cnt; 1355 if (IPOPT_COPIED(opt)) { 1356 bcopy(cp, dp, optlen); 1357 dp += optlen; 1358 } 1359 } 1360 for (optlen = dp - (u_char *)(jp+1); optlen & 0x3; optlen++) 1361 *dp++ = IPOPT_EOL; 1362 return (optlen); 1363 } 1364 1365 /* 1366 * IP socket option processing. 1367 */ 1368 int 1369 ip_ctloutput(struct socket *so, struct sockopt *sopt) 1370 { 1371 struct inpcb *inp = so->so_pcb; 1372 int error, optval; 1373 1374 error = optval = 0; 1375 if (sopt->sopt_level != IPPROTO_IP) { 1376 return (EINVAL); 1377 } 1378 1379 switch (sopt->sopt_dir) { 1380 case SOPT_SET: 1381 switch (sopt->sopt_name) { 1382 case IP_OPTIONS: 1383 #ifdef notyet 1384 case IP_RETOPTS: 1385 #endif 1386 { 1387 struct mbuf *m; 1388 if (sopt->sopt_valsize > MLEN) { 1389 error = EMSGSIZE; 1390 break; 1391 } 1392 MGET(m, sopt->sopt_td ? MB_WAIT : MB_DONTWAIT, MT_HEADER); 1393 if (m == NULL) { 1394 error = ENOBUFS; 1395 break; 1396 } 1397 m->m_len = sopt->sopt_valsize; 1398 error = sooptcopyin(sopt, mtod(m, char *), m->m_len, 1399 m->m_len); 1400 1401 return (ip_pcbopts(sopt->sopt_name, &inp->inp_options, 1402 m)); 1403 } 1404 1405 case IP_TOS: 1406 case IP_TTL: 1407 case IP_RECVOPTS: 1408 case IP_RECVRETOPTS: 1409 case IP_RECVDSTADDR: 1410 case IP_RECVIF: 1411 case IP_FAITH: 1412 error = sooptcopyin(sopt, &optval, sizeof optval, 1413 sizeof optval); 1414 if (error) 1415 break; 1416 1417 switch (sopt->sopt_name) { 1418 case IP_TOS: 1419 inp->inp_ip_tos = optval; 1420 break; 1421 1422 case IP_TTL: 1423 inp->inp_ip_ttl = optval; 1424 break; 1425 #define OPTSET(bit) \ 1426 if (optval) \ 1427 inp->inp_flags |= bit; \ 1428 else \ 1429 inp->inp_flags &= ~bit; 1430 1431 case IP_RECVOPTS: 1432 OPTSET(INP_RECVOPTS); 1433 break; 1434 1435 case IP_RECVRETOPTS: 1436 OPTSET(INP_RECVRETOPTS); 1437 break; 1438 1439 case IP_RECVDSTADDR: 1440 OPTSET(INP_RECVDSTADDR); 1441 break; 1442 1443 case IP_RECVIF: 1444 OPTSET(INP_RECVIF); 1445 break; 1446 1447 case IP_FAITH: 1448 OPTSET(INP_FAITH); 1449 break; 1450 } 1451 break; 1452 #undef OPTSET 1453 1454 case IP_MULTICAST_IF: 1455 case IP_MULTICAST_VIF: 1456 case IP_MULTICAST_TTL: 1457 case IP_MULTICAST_LOOP: 1458 case IP_ADD_MEMBERSHIP: 1459 case IP_DROP_MEMBERSHIP: 1460 error = ip_setmoptions(sopt, &inp->inp_moptions); 1461 break; 1462 1463 case IP_PORTRANGE: 1464 error = sooptcopyin(sopt, &optval, sizeof optval, 1465 sizeof optval); 1466 if (error) 1467 break; 1468 1469 switch (optval) { 1470 case IP_PORTRANGE_DEFAULT: 1471 inp->inp_flags &= ~(INP_LOWPORT); 1472 inp->inp_flags &= ~(INP_HIGHPORT); 1473 break; 1474 1475 case IP_PORTRANGE_HIGH: 1476 inp->inp_flags &= ~(INP_LOWPORT); 1477 inp->inp_flags |= INP_HIGHPORT; 1478 break; 1479 1480 case IP_PORTRANGE_LOW: 1481 inp->inp_flags &= ~(INP_HIGHPORT); 1482 inp->inp_flags |= INP_LOWPORT; 1483 break; 1484 1485 default: 1486 error = EINVAL; 1487 break; 1488 } 1489 break; 1490 1491 #if defined(IPSEC) || defined(FAST_IPSEC) 1492 case IP_IPSEC_POLICY: 1493 { 1494 caddr_t req; 1495 size_t len = 0; 1496 int priv; 1497 struct mbuf *m; 1498 int optname; 1499 1500 if ((error = soopt_getm(sopt, &m)) != 0) /* XXX */ 1501 break; 1502 if ((error = soopt_mcopyin(sopt, m)) != 0) /* XXX */ 1503 break; 1504 priv = (sopt->sopt_td != NULL && 1505 suser(sopt->sopt_td) != 0) ? 0 : 1; 1506 req = mtod(m, caddr_t); 1507 len = m->m_len; 1508 optname = sopt->sopt_name; 1509 error = ipsec4_set_policy(inp, optname, req, len, priv); 1510 m_freem(m); 1511 break; 1512 } 1513 #endif /*IPSEC*/ 1514 1515 default: 1516 error = ENOPROTOOPT; 1517 break; 1518 } 1519 break; 1520 1521 case SOPT_GET: 1522 switch (sopt->sopt_name) { 1523 case IP_OPTIONS: 1524 case IP_RETOPTS: 1525 if (inp->inp_options) 1526 error = sooptcopyout(sopt, 1527 mtod(inp->inp_options, 1528 char *), 1529 inp->inp_options->m_len); 1530 else 1531 sopt->sopt_valsize = 0; 1532 break; 1533 1534 case IP_TOS: 1535 case IP_TTL: 1536 case IP_RECVOPTS: 1537 case IP_RECVRETOPTS: 1538 case IP_RECVDSTADDR: 1539 case IP_RECVIF: 1540 case IP_PORTRANGE: 1541 case IP_FAITH: 1542 switch (sopt->sopt_name) { 1543 1544 case IP_TOS: 1545 optval = inp->inp_ip_tos; 1546 break; 1547 1548 case IP_TTL: 1549 optval = inp->inp_ip_ttl; 1550 break; 1551 1552 #define OPTBIT(bit) (inp->inp_flags & bit ? 1 : 0) 1553 1554 case IP_RECVOPTS: 1555 optval = OPTBIT(INP_RECVOPTS); 1556 break; 1557 1558 case IP_RECVRETOPTS: 1559 optval = OPTBIT(INP_RECVRETOPTS); 1560 break; 1561 1562 case IP_RECVDSTADDR: 1563 optval = OPTBIT(INP_RECVDSTADDR); 1564 break; 1565 1566 case IP_RECVIF: 1567 optval = OPTBIT(INP_RECVIF); 1568 break; 1569 1570 case IP_PORTRANGE: 1571 if (inp->inp_flags & INP_HIGHPORT) 1572 optval = IP_PORTRANGE_HIGH; 1573 else if (inp->inp_flags & INP_LOWPORT) 1574 optval = IP_PORTRANGE_LOW; 1575 else 1576 optval = 0; 1577 break; 1578 1579 case IP_FAITH: 1580 optval = OPTBIT(INP_FAITH); 1581 break; 1582 } 1583 error = sooptcopyout(sopt, &optval, sizeof optval); 1584 break; 1585 1586 case IP_MULTICAST_IF: 1587 case IP_MULTICAST_VIF: 1588 case IP_MULTICAST_TTL: 1589 case IP_MULTICAST_LOOP: 1590 case IP_ADD_MEMBERSHIP: 1591 case IP_DROP_MEMBERSHIP: 1592 error = ip_getmoptions(sopt, inp->inp_moptions); 1593 break; 1594 1595 #if defined(IPSEC) || defined(FAST_IPSEC) 1596 case IP_IPSEC_POLICY: 1597 { 1598 struct mbuf *m = NULL; 1599 caddr_t req = NULL; 1600 size_t len = 0; 1601 1602 if (m != NULL) { 1603 req = mtod(m, caddr_t); 1604 len = m->m_len; 1605 } 1606 error = ipsec4_get_policy(so->so_pcb, req, len, &m); 1607 if (error == 0) 1608 error = soopt_mcopyout(sopt, m); /* XXX */ 1609 if (error == 0) 1610 m_freem(m); 1611 break; 1612 } 1613 #endif /*IPSEC*/ 1614 1615 default: 1616 error = ENOPROTOOPT; 1617 break; 1618 } 1619 break; 1620 } 1621 return (error); 1622 } 1623 1624 /* 1625 * Set up IP options in pcb for insertion in output packets. 1626 * Store in mbuf with pointer in pcbopt, adding pseudo-option 1627 * with destination address if source routed. 1628 */ 1629 static int 1630 ip_pcbopts(int optname, struct mbuf **pcbopt, struct mbuf *m) 1631 { 1632 int cnt, optlen; 1633 u_char *cp; 1634 u_char opt; 1635 1636 /* turn off any old options */ 1637 if (*pcbopt) 1638 m_free(*pcbopt); 1639 *pcbopt = 0; 1640 if (m == NULL || m->m_len == 0) { 1641 /* 1642 * Only turning off any previous options. 1643 */ 1644 if (m != NULL) 1645 m_free(m); 1646 return (0); 1647 } 1648 1649 if (m->m_len % sizeof(int32_t)) 1650 goto bad; 1651 /* 1652 * IP first-hop destination address will be stored before 1653 * actual options; move other options back 1654 * and clear it when none present. 1655 */ 1656 if (m->m_data + m->m_len + sizeof(struct in_addr) >= &m->m_dat[MLEN]) 1657 goto bad; 1658 cnt = m->m_len; 1659 m->m_len += sizeof(struct in_addr); 1660 cp = mtod(m, u_char *) + sizeof(struct in_addr); 1661 ovbcopy(mtod(m, caddr_t), cp, cnt); 1662 bzero(mtod(m, caddr_t), sizeof(struct in_addr)); 1663 1664 for (; cnt > 0; cnt -= optlen, cp += optlen) { 1665 opt = cp[IPOPT_OPTVAL]; 1666 if (opt == IPOPT_EOL) 1667 break; 1668 if (opt == IPOPT_NOP) 1669 optlen = 1; 1670 else { 1671 if (cnt < IPOPT_OLEN + sizeof *cp) 1672 goto bad; 1673 optlen = cp[IPOPT_OLEN]; 1674 if (optlen < IPOPT_OLEN + sizeof *cp || optlen > cnt) 1675 goto bad; 1676 } 1677 switch (opt) { 1678 1679 default: 1680 break; 1681 1682 case IPOPT_LSRR: 1683 case IPOPT_SSRR: 1684 /* 1685 * user process specifies route as: 1686 * ->A->B->C->D 1687 * D must be our final destination (but we can't 1688 * check that since we may not have connected yet). 1689 * A is first hop destination, which doesn't appear in 1690 * actual IP option, but is stored before the options. 1691 */ 1692 if (optlen < IPOPT_MINOFF - 1 + sizeof(struct in_addr)) 1693 goto bad; 1694 m->m_len -= sizeof(struct in_addr); 1695 cnt -= sizeof(struct in_addr); 1696 optlen -= sizeof(struct in_addr); 1697 cp[IPOPT_OLEN] = optlen; 1698 /* 1699 * Move first hop before start of options. 1700 */ 1701 bcopy(&cp[IPOPT_OFFSET+1], mtod(m, caddr_t), 1702 sizeof(struct in_addr)); 1703 /* 1704 * Then copy rest of options back 1705 * to close up the deleted entry. 1706 */ 1707 ovbcopy(&cp[IPOPT_OFFSET+1] + sizeof(struct in_addr), 1708 &cp[IPOPT_OFFSET+1], 1709 cnt - (IPOPT_MINOFF - 1)); 1710 break; 1711 } 1712 } 1713 if (m->m_len > MAX_IPOPTLEN + sizeof(struct in_addr)) 1714 goto bad; 1715 *pcbopt = m; 1716 return (0); 1717 1718 bad: 1719 m_free(m); 1720 return (EINVAL); 1721 } 1722 1723 /* 1724 * XXX 1725 * The whole multicast option thing needs to be re-thought. 1726 * Several of these options are equally applicable to non-multicast 1727 * transmission, and one (IP_MULTICAST_TTL) totally duplicates a 1728 * standard option (IP_TTL). 1729 */ 1730 1731 /* 1732 * following RFC1724 section 3.3, 0.0.0.0/8 is interpreted as interface index. 1733 */ 1734 static struct ifnet * 1735 ip_multicast_if(struct in_addr *a, int *ifindexp) 1736 { 1737 int ifindex; 1738 struct ifnet *ifp; 1739 1740 if (ifindexp) 1741 *ifindexp = 0; 1742 if (ntohl(a->s_addr) >> 24 == 0) { 1743 ifindex = ntohl(a->s_addr) & 0xffffff; 1744 if (ifindex < 0 || if_index < ifindex) 1745 return NULL; 1746 ifp = ifindex2ifnet[ifindex]; 1747 if (ifindexp) 1748 *ifindexp = ifindex; 1749 } else { 1750 INADDR_TO_IFP(*a, ifp); 1751 } 1752 return ifp; 1753 } 1754 1755 /* 1756 * Set the IP multicast options in response to user setsockopt(). 1757 */ 1758 static int 1759 ip_setmoptions(struct sockopt *sopt, struct ip_moptions **imop) 1760 { 1761 int error = 0; 1762 int i; 1763 struct in_addr addr; 1764 struct ip_mreq mreq; 1765 struct ifnet *ifp; 1766 struct ip_moptions *imo = *imop; 1767 int ifindex; 1768 1769 if (imo == NULL) { 1770 /* 1771 * No multicast option buffer attached to the pcb; 1772 * allocate one and initialize to default values. 1773 */ 1774 imo = malloc(sizeof *imo, M_IPMOPTS, M_WAITOK); 1775 1776 if (imo == NULL) 1777 return (ENOBUFS); 1778 *imop = imo; 1779 imo->imo_multicast_ifp = NULL; 1780 imo->imo_multicast_addr.s_addr = INADDR_ANY; 1781 imo->imo_multicast_vif = -1; 1782 imo->imo_multicast_ttl = IP_DEFAULT_MULTICAST_TTL; 1783 imo->imo_multicast_loop = IP_DEFAULT_MULTICAST_LOOP; 1784 imo->imo_num_memberships = 0; 1785 } 1786 1787 switch (sopt->sopt_name) { 1788 /* store an index number for the vif you wanna use in the send */ 1789 case IP_MULTICAST_VIF: 1790 if (legal_vif_num == 0) { 1791 error = EOPNOTSUPP; 1792 break; 1793 } 1794 error = sooptcopyin(sopt, &i, sizeof i, sizeof i); 1795 if (error) 1796 break; 1797 if (!legal_vif_num(i) && (i != -1)) { 1798 error = EINVAL; 1799 break; 1800 } 1801 imo->imo_multicast_vif = i; 1802 break; 1803 1804 case IP_MULTICAST_IF: 1805 /* 1806 * Select the interface for outgoing multicast packets. 1807 */ 1808 error = sooptcopyin(sopt, &addr, sizeof addr, sizeof addr); 1809 if (error) 1810 break; 1811 /* 1812 * INADDR_ANY is used to remove a previous selection. 1813 * When no interface is selected, a default one is 1814 * chosen every time a multicast packet is sent. 1815 */ 1816 if (addr.s_addr == INADDR_ANY) { 1817 imo->imo_multicast_ifp = NULL; 1818 break; 1819 } 1820 /* 1821 * The selected interface is identified by its local 1822 * IP address. Find the interface and confirm that 1823 * it supports multicasting. 1824 */ 1825 crit_enter(); 1826 ifp = ip_multicast_if(&addr, &ifindex); 1827 if (ifp == NULL || !(ifp->if_flags & IFF_MULTICAST)) { 1828 crit_exit(); 1829 error = EADDRNOTAVAIL; 1830 break; 1831 } 1832 imo->imo_multicast_ifp = ifp; 1833 if (ifindex) 1834 imo->imo_multicast_addr = addr; 1835 else 1836 imo->imo_multicast_addr.s_addr = INADDR_ANY; 1837 crit_exit(); 1838 break; 1839 1840 case IP_MULTICAST_TTL: 1841 /* 1842 * Set the IP time-to-live for outgoing multicast packets. 1843 * The original multicast API required a char argument, 1844 * which is inconsistent with the rest of the socket API. 1845 * We allow either a char or an int. 1846 */ 1847 if (sopt->sopt_valsize == 1) { 1848 u_char ttl; 1849 error = sooptcopyin(sopt, &ttl, 1, 1); 1850 if (error) 1851 break; 1852 imo->imo_multicast_ttl = ttl; 1853 } else { 1854 u_int ttl; 1855 error = sooptcopyin(sopt, &ttl, sizeof ttl, sizeof ttl); 1856 if (error) 1857 break; 1858 if (ttl > 255) 1859 error = EINVAL; 1860 else 1861 imo->imo_multicast_ttl = ttl; 1862 } 1863 break; 1864 1865 case IP_MULTICAST_LOOP: 1866 /* 1867 * Set the loopback flag for outgoing multicast packets. 1868 * Must be zero or one. The original multicast API required a 1869 * char argument, which is inconsistent with the rest 1870 * of the socket API. We allow either a char or an int. 1871 */ 1872 if (sopt->sopt_valsize == 1) { 1873 u_char loop; 1874 1875 error = sooptcopyin(sopt, &loop, 1, 1); 1876 if (error) 1877 break; 1878 imo->imo_multicast_loop = !!loop; 1879 } else { 1880 u_int loop; 1881 1882 error = sooptcopyin(sopt, &loop, sizeof loop, 1883 sizeof loop); 1884 if (error) 1885 break; 1886 imo->imo_multicast_loop = !!loop; 1887 } 1888 break; 1889 1890 case IP_ADD_MEMBERSHIP: 1891 /* 1892 * Add a multicast group membership. 1893 * Group must be a valid IP multicast address. 1894 */ 1895 error = sooptcopyin(sopt, &mreq, sizeof mreq, sizeof mreq); 1896 if (error) 1897 break; 1898 1899 if (!IN_MULTICAST(ntohl(mreq.imr_multiaddr.s_addr))) { 1900 error = EINVAL; 1901 break; 1902 } 1903 crit_enter(); 1904 /* 1905 * If no interface address was provided, use the interface of 1906 * the route to the given multicast address. 1907 */ 1908 if (mreq.imr_interface.s_addr == INADDR_ANY) { 1909 struct sockaddr_in dst; 1910 struct rtentry *rt; 1911 1912 bzero(&dst, sizeof(struct sockaddr_in)); 1913 dst.sin_len = sizeof(struct sockaddr_in); 1914 dst.sin_family = AF_INET; 1915 dst.sin_addr = mreq.imr_multiaddr; 1916 rt = rtlookup((struct sockaddr *)&dst); 1917 if (rt == NULL) { 1918 error = EADDRNOTAVAIL; 1919 crit_exit(); 1920 break; 1921 } 1922 --rt->rt_refcnt; 1923 ifp = rt->rt_ifp; 1924 } else { 1925 ifp = ip_multicast_if(&mreq.imr_interface, NULL); 1926 } 1927 1928 /* 1929 * See if we found an interface, and confirm that it 1930 * supports multicast. 1931 */ 1932 if (ifp == NULL || !(ifp->if_flags & IFF_MULTICAST)) { 1933 error = EADDRNOTAVAIL; 1934 crit_exit(); 1935 break; 1936 } 1937 /* 1938 * See if the membership already exists or if all the 1939 * membership slots are full. 1940 */ 1941 for (i = 0; i < imo->imo_num_memberships; ++i) { 1942 if (imo->imo_membership[i]->inm_ifp == ifp && 1943 imo->imo_membership[i]->inm_addr.s_addr 1944 == mreq.imr_multiaddr.s_addr) 1945 break; 1946 } 1947 if (i < imo->imo_num_memberships) { 1948 error = EADDRINUSE; 1949 crit_exit(); 1950 break; 1951 } 1952 if (i == IP_MAX_MEMBERSHIPS) { 1953 error = ETOOMANYREFS; 1954 crit_exit(); 1955 break; 1956 } 1957 /* 1958 * Everything looks good; add a new record to the multicast 1959 * address list for the given interface. 1960 */ 1961 if ((imo->imo_membership[i] = 1962 in_addmulti(&mreq.imr_multiaddr, ifp)) == NULL) { 1963 error = ENOBUFS; 1964 crit_exit(); 1965 break; 1966 } 1967 ++imo->imo_num_memberships; 1968 crit_exit(); 1969 break; 1970 1971 case IP_DROP_MEMBERSHIP: 1972 /* 1973 * Drop a multicast group membership. 1974 * Group must be a valid IP multicast address. 1975 */ 1976 error = sooptcopyin(sopt, &mreq, sizeof mreq, sizeof mreq); 1977 if (error) 1978 break; 1979 1980 if (!IN_MULTICAST(ntohl(mreq.imr_multiaddr.s_addr))) { 1981 error = EINVAL; 1982 break; 1983 } 1984 1985 crit_enter(); 1986 /* 1987 * If an interface address was specified, get a pointer 1988 * to its ifnet structure. 1989 */ 1990 if (mreq.imr_interface.s_addr == INADDR_ANY) 1991 ifp = NULL; 1992 else { 1993 ifp = ip_multicast_if(&mreq.imr_interface, NULL); 1994 if (ifp == NULL) { 1995 error = EADDRNOTAVAIL; 1996 crit_exit(); 1997 break; 1998 } 1999 } 2000 /* 2001 * Find the membership in the membership array. 2002 */ 2003 for (i = 0; i < imo->imo_num_memberships; ++i) { 2004 if ((ifp == NULL || 2005 imo->imo_membership[i]->inm_ifp == ifp) && 2006 imo->imo_membership[i]->inm_addr.s_addr == 2007 mreq.imr_multiaddr.s_addr) 2008 break; 2009 } 2010 if (i == imo->imo_num_memberships) { 2011 error = EADDRNOTAVAIL; 2012 crit_exit(); 2013 break; 2014 } 2015 /* 2016 * Give up the multicast address record to which the 2017 * membership points. 2018 */ 2019 in_delmulti(imo->imo_membership[i]); 2020 /* 2021 * Remove the gap in the membership array. 2022 */ 2023 for (++i; i < imo->imo_num_memberships; ++i) 2024 imo->imo_membership[i-1] = imo->imo_membership[i]; 2025 --imo->imo_num_memberships; 2026 crit_exit(); 2027 break; 2028 2029 default: 2030 error = EOPNOTSUPP; 2031 break; 2032 } 2033 2034 /* 2035 * If all options have default values, no need to keep the mbuf. 2036 */ 2037 if (imo->imo_multicast_ifp == NULL && 2038 imo->imo_multicast_vif == -1 && 2039 imo->imo_multicast_ttl == IP_DEFAULT_MULTICAST_TTL && 2040 imo->imo_multicast_loop == IP_DEFAULT_MULTICAST_LOOP && 2041 imo->imo_num_memberships == 0) { 2042 free(*imop, M_IPMOPTS); 2043 *imop = NULL; 2044 } 2045 2046 return (error); 2047 } 2048 2049 /* 2050 * Return the IP multicast options in response to user getsockopt(). 2051 */ 2052 static int 2053 ip_getmoptions(struct sockopt *sopt, struct ip_moptions *imo) 2054 { 2055 struct in_addr addr; 2056 struct in_ifaddr *ia; 2057 int error, optval; 2058 u_char coptval; 2059 2060 error = 0; 2061 switch (sopt->sopt_name) { 2062 case IP_MULTICAST_VIF: 2063 if (imo != NULL) 2064 optval = imo->imo_multicast_vif; 2065 else 2066 optval = -1; 2067 error = sooptcopyout(sopt, &optval, sizeof optval); 2068 break; 2069 2070 case IP_MULTICAST_IF: 2071 if (imo == NULL || imo->imo_multicast_ifp == NULL) 2072 addr.s_addr = INADDR_ANY; 2073 else if (imo->imo_multicast_addr.s_addr) { 2074 /* return the value user has set */ 2075 addr = imo->imo_multicast_addr; 2076 } else { 2077 IFP_TO_IA(imo->imo_multicast_ifp, ia); 2078 addr.s_addr = (ia == NULL) ? INADDR_ANY 2079 : IA_SIN(ia)->sin_addr.s_addr; 2080 } 2081 error = sooptcopyout(sopt, &addr, sizeof addr); 2082 break; 2083 2084 case IP_MULTICAST_TTL: 2085 if (imo == NULL) 2086 optval = coptval = IP_DEFAULT_MULTICAST_TTL; 2087 else 2088 optval = coptval = imo->imo_multicast_ttl; 2089 if (sopt->sopt_valsize == 1) 2090 error = sooptcopyout(sopt, &coptval, 1); 2091 else 2092 error = sooptcopyout(sopt, &optval, sizeof optval); 2093 break; 2094 2095 case IP_MULTICAST_LOOP: 2096 if (imo == NULL) 2097 optval = coptval = IP_DEFAULT_MULTICAST_LOOP; 2098 else 2099 optval = coptval = imo->imo_multicast_loop; 2100 if (sopt->sopt_valsize == 1) 2101 error = sooptcopyout(sopt, &coptval, 1); 2102 else 2103 error = sooptcopyout(sopt, &optval, sizeof optval); 2104 break; 2105 2106 default: 2107 error = ENOPROTOOPT; 2108 break; 2109 } 2110 return (error); 2111 } 2112 2113 /* 2114 * Discard the IP multicast options. 2115 */ 2116 void 2117 ip_freemoptions(struct ip_moptions *imo) 2118 { 2119 int i; 2120 2121 if (imo != NULL) { 2122 for (i = 0; i < imo->imo_num_memberships; ++i) 2123 in_delmulti(imo->imo_membership[i]); 2124 free(imo, M_IPMOPTS); 2125 } 2126 } 2127 2128 /* 2129 * Routine called from ip_output() to loop back a copy of an IP multicast 2130 * packet to the input queue of a specified interface. Note that this 2131 * calls the output routine of the loopback "driver", but with an interface 2132 * pointer that might NOT be a loopback interface -- evil, but easier than 2133 * replicating that code here. 2134 */ 2135 static void 2136 ip_mloopback(struct ifnet *ifp, struct mbuf *m, struct sockaddr_in *dst, 2137 int hlen) 2138 { 2139 struct ip *ip; 2140 struct mbuf *copym; 2141 2142 copym = m_copypacket(m, MB_DONTWAIT); 2143 if (copym != NULL && (copym->m_flags & M_EXT || copym->m_len < hlen)) 2144 copym = m_pullup(copym, hlen); 2145 if (copym != NULL) { 2146 /* 2147 * if the checksum hasn't been computed, mark it as valid 2148 */ 2149 if (copym->m_pkthdr.csum_flags & CSUM_DELAY_DATA) { 2150 in_delayed_cksum(copym); 2151 copym->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA; 2152 copym->m_pkthdr.csum_flags |= 2153 CSUM_DATA_VALID | CSUM_PSEUDO_HDR; 2154 copym->m_pkthdr.csum_data = 0xffff; 2155 } 2156 /* 2157 * We don't bother to fragment if the IP length is greater 2158 * than the interface's MTU. Can this possibly matter? 2159 */ 2160 ip = mtod(copym, struct ip *); 2161 ip->ip_len = htons(ip->ip_len); 2162 ip->ip_off = htons(ip->ip_off); 2163 ip->ip_sum = 0; 2164 if (ip->ip_vhl == IP_VHL_BORING) { 2165 ip->ip_sum = in_cksum_hdr(ip); 2166 } else { 2167 ip->ip_sum = in_cksum(copym, hlen); 2168 } 2169 /* 2170 * NB: 2171 * It's not clear whether there are any lingering 2172 * reentrancy problems in other areas which might 2173 * be exposed by using ip_input directly (in 2174 * particular, everything which modifies the packet 2175 * in-place). Yet another option is using the 2176 * protosw directly to deliver the looped back 2177 * packet. For the moment, we'll err on the side 2178 * of safety by using if_simloop(). 2179 */ 2180 #if 1 /* XXX */ 2181 if (dst->sin_family != AF_INET) { 2182 printf("ip_mloopback: bad address family %d\n", 2183 dst->sin_family); 2184 dst->sin_family = AF_INET; 2185 } 2186 #endif 2187 2188 #ifdef notdef 2189 copym->m_pkthdr.rcvif = ifp; 2190 ip_input(copym); 2191 #else 2192 if_simloop(ifp, copym, dst->sin_family, 0); 2193 #endif 2194 } 2195 } 2196