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sys/netinet/ip_output.c
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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. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * @(#)ip_output.c 8.3 (Berkeley) 1/21/94 34 * $FreeBSD: releng/5.1/sys/netinet/ip_output.c 114258 2003-04-29 21:36:18Z mdodd $ 35 */ 36 37 #include "opt_ipfw.h" 38 #include "opt_ipdn.h" 39 #include "opt_ipdivert.h" 40 #include "opt_ipfilter.h" 41 #include "opt_ipsec.h" 42 #include "opt_mac.h" 43 #include "opt_pfil_hooks.h" 44 #include "opt_random_ip_id.h" 45 #include "opt_mbuf_stress_test.h" 46 47 #include <sys/param.h> 48 #include <sys/systm.h> 49 #include <sys/kernel.h> 50 #include <sys/mac.h> 51 #include <sys/malloc.h> 52 #include <sys/mbuf.h> 53 #include <sys/protosw.h> 54 #include <sys/socket.h> 55 #include <sys/socketvar.h> 56 #include <sys/sysctl.h> 57 58 #include <net/if.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 #include <machine/in_cksum.h> 69 70 static MALLOC_DEFINE(M_IPMOPTS, "ip_moptions", "internet multicast options"); 71 72 #ifdef IPSEC 73 #include <netinet6/ipsec.h> 74 #include <netkey/key.h> 75 #ifdef IPSEC_DEBUG 76 #include <netkey/key_debug.h> 77 #else 78 #define KEYDEBUG(lev,arg) 79 #endif 80 #endif /*IPSEC*/ 81 82 #ifdef FAST_IPSEC 83 #include <netipsec/ipsec.h> 84 #include <netipsec/xform.h> 85 #include <netipsec/key.h> 86 #endif /*FAST_IPSEC*/ 87 88 #include <netinet/ip_fw.h> 89 #include <netinet/ip_dummynet.h> 90 91 #define print_ip(x, a, y) printf("%s %d.%d.%d.%d%s",\ 92 x, (ntohl(a.s_addr)>>24)&0xFF,\ 93 (ntohl(a.s_addr)>>16)&0xFF,\ 94 (ntohl(a.s_addr)>>8)&0xFF,\ 95 (ntohl(a.s_addr))&0xFF, y); 96 97 u_short ip_id; 98 99 #ifdef MBUF_STRESS_TEST 100 int mbuf_frag_size = 0; 101 SYSCTL_INT(_net_inet_ip, OID_AUTO, mbuf_frag_size, CTLFLAG_RW, 102 &mbuf_frag_size, 0, "Fragment outgoing mbufs to this size"); 103 #endif 104 105 static struct mbuf *ip_insertoptions(struct mbuf *, struct mbuf *, int *); 106 static struct ifnet *ip_multicast_if(struct in_addr *, int *); 107 static void ip_mloopback 108 (struct ifnet *, struct mbuf *, struct sockaddr_in *, int); 109 static int ip_getmoptions 110 (struct sockopt *, struct ip_moptions *); 111 static int ip_pcbopts(int, struct mbuf **, struct mbuf *); 112 static int ip_setmoptions 113 (struct sockopt *, struct ip_moptions **); 114 115 int ip_optcopy(struct ip *, struct ip *); 116 117 118 extern struct protosw inetsw[]; 119 120 /* 121 * IP output. The packet in mbuf chain m contains a skeletal IP 122 * header (with len, off, ttl, proto, tos, src, dst). 123 * The mbuf chain containing the packet will be freed. 124 * The mbuf opt, if present, will not be freed. 125 */ 126 int 127 ip_output(m0, opt, ro, flags, imo, inp) 128 struct mbuf *m0; 129 struct mbuf *opt; 130 struct route *ro; 131 int flags; 132 struct ip_moptions *imo; 133 struct inpcb *inp; 134 { 135 struct ip *ip, *mhip; 136 struct ifnet *ifp = NULL; /* keep compiler happy */ 137 struct mbuf *m; 138 int hlen = sizeof (struct ip); 139 int len, off, error = 0; 140 struct sockaddr_in *dst = NULL; /* keep compiler happy */ 141 struct in_ifaddr *ia = NULL; 142 int isbroadcast, sw_csum; 143 struct in_addr pkt_dst; 144 #ifdef IPSEC 145 struct route iproute; 146 struct secpolicy *sp = NULL; 147 #endif 148 #ifdef FAST_IPSEC 149 struct route iproute; 150 struct m_tag *mtag; 151 struct secpolicy *sp = NULL; 152 struct tdb_ident *tdbi; 153 int s; 154 #endif /* FAST_IPSEC */ 155 struct ip_fw_args args; 156 int src_was_INADDR_ANY = 0; /* as the name says... */ 157 #ifdef PFIL_HOOKS 158 struct packet_filter_hook *pfh; 159 struct mbuf *m1; 160 int rv; 161 #endif /* PFIL_HOOKS */ 162 163 args.eh = NULL; 164 args.rule = NULL; 165 args.next_hop = NULL; 166 args.divert_rule = 0; /* divert cookie */ 167 168 /* Grab info from MT_TAG mbufs prepended to the chain. */ 169 for (; m0 && m0->m_type == MT_TAG; m0 = m0->m_next) { 170 switch(m0->_m_tag_id) { 171 default: 172 printf("ip_output: unrecognised MT_TAG tag %d\n", 173 m0->_m_tag_id); 174 break; 175 176 case PACKET_TAG_DUMMYNET: 177 /* 178 * the packet was already tagged, so part of the 179 * processing was already done, and we need to go down. 180 * Get parameters from the header. 181 */ 182 args.rule = ((struct dn_pkt *)m0)->rule; 183 opt = NULL ; 184 ro = & ( ((struct dn_pkt *)m0)->ro ) ; 185 imo = NULL ; 186 dst = ((struct dn_pkt *)m0)->dn_dst ; 187 ifp = ((struct dn_pkt *)m0)->ifp ; 188 flags = ((struct dn_pkt *)m0)->flags ; 189 break; 190 191 case PACKET_TAG_DIVERT: 192 args.divert_rule = (intptr_t)m0->m_data & 0xffff; 193 break; 194 195 case PACKET_TAG_IPFORWARD: 196 args.next_hop = (struct sockaddr_in *)m0->m_data; 197 break; 198 } 199 } 200 m = m0; 201 202 M_ASSERTPKTHDR(m); 203 #ifndef FAST_IPSEC 204 KASSERT(ro != NULL, ("ip_output: no route, proto %d", 205 mtod(m, struct ip *)->ip_p)); 206 #endif 207 208 if (args.rule != NULL) { /* dummynet already saw us */ 209 ip = mtod(m, struct ip *); 210 hlen = ip->ip_hl << 2 ; 211 if (ro->ro_rt) 212 ia = ifatoia(ro->ro_rt->rt_ifa); 213 goto sendit; 214 } 215 216 if (opt) { 217 len = 0; 218 m = ip_insertoptions(m, opt, &len); 219 if (len != 0) 220 hlen = len; 221 } 222 ip = mtod(m, struct ip *); 223 pkt_dst = args.next_hop ? args.next_hop->sin_addr : ip->ip_dst; 224 225 /* 226 * Fill in IP header. 227 */ 228 if ((flags & (IP_FORWARDING|IP_RAWOUTPUT)) == 0) { 229 ip->ip_v = IPVERSION; 230 ip->ip_hl = hlen >> 2; 231 ip->ip_off &= IP_DF; 232 #ifdef RANDOM_IP_ID 233 ip->ip_id = ip_randomid(); 234 #else 235 ip->ip_id = htons(ip_id++); 236 #endif 237 ipstat.ips_localout++; 238 } else { 239 hlen = ip->ip_hl << 2; 240 } 241 242 #ifdef FAST_IPSEC 243 if (ro == NULL) { 244 ro = &iproute; 245 bzero(ro, sizeof (*ro)); 246 } 247 #endif /* FAST_IPSEC */ 248 dst = (struct sockaddr_in *)&ro->ro_dst; 249 /* 250 * If there is a cached route, 251 * check that it is to the same destination 252 * and is still up. If not, free it and try again. 253 * The address family should also be checked in case of sharing the 254 * cache with IPv6. 255 */ 256 if (ro->ro_rt && ((ro->ro_rt->rt_flags & RTF_UP) == 0 || 257 dst->sin_family != AF_INET || 258 dst->sin_addr.s_addr != pkt_dst.s_addr)) { 259 RTFREE(ro->ro_rt); 260 ro->ro_rt = (struct rtentry *)0; 261 } 262 if (ro->ro_rt == 0) { 263 bzero(dst, sizeof(*dst)); 264 dst->sin_family = AF_INET; 265 dst->sin_len = sizeof(*dst); 266 dst->sin_addr = pkt_dst; 267 } 268 /* 269 * If routing to interface only, 270 * short circuit routing lookup. 271 */ 272 if (flags & IP_ROUTETOIF) { 273 if ((ia = ifatoia(ifa_ifwithdstaddr(sintosa(dst)))) == 0 && 274 (ia = ifatoia(ifa_ifwithnet(sintosa(dst)))) == 0) { 275 ipstat.ips_noroute++; 276 error = ENETUNREACH; 277 goto bad; 278 } 279 ifp = ia->ia_ifp; 280 ip->ip_ttl = 1; 281 isbroadcast = in_broadcast(dst->sin_addr, ifp); 282 } else if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) && 283 imo != NULL && imo->imo_multicast_ifp != NULL) { 284 /* 285 * Bypass the normal routing lookup for multicast 286 * packets if the interface is specified. 287 */ 288 ifp = imo->imo_multicast_ifp; 289 IFP_TO_IA(ifp, ia); 290 isbroadcast = 0; /* fool gcc */ 291 } else { 292 /* 293 * If this is the case, we probably don't want to allocate 294 * a protocol-cloned route since we didn't get one from the 295 * ULP. This lets TCP do its thing, while not burdening 296 * forwarding or ICMP with the overhead of cloning a route. 297 * Of course, we still want to do any cloning requested by 298 * the link layer, as this is probably required in all cases 299 * for correct operation (as it is for ARP). 300 */ 301 if (ro->ro_rt == 0) 302 rtalloc_ign(ro, RTF_PRCLONING); 303 if (ro->ro_rt == 0) { 304 ipstat.ips_noroute++; 305 error = EHOSTUNREACH; 306 goto bad; 307 } 308 ia = ifatoia(ro->ro_rt->rt_ifa); 309 ifp = ro->ro_rt->rt_ifp; 310 ro->ro_rt->rt_use++; 311 if (ro->ro_rt->rt_flags & RTF_GATEWAY) 312 dst = (struct sockaddr_in *)ro->ro_rt->rt_gateway; 313 if (ro->ro_rt->rt_flags & RTF_HOST) 314 isbroadcast = (ro->ro_rt->rt_flags & RTF_BROADCAST); 315 else 316 isbroadcast = in_broadcast(dst->sin_addr, ifp); 317 } 318 if (IN_MULTICAST(ntohl(pkt_dst.s_addr))) { 319 struct in_multi *inm; 320 321 m->m_flags |= M_MCAST; 322 /* 323 * IP destination address is multicast. Make sure "dst" 324 * still points to the address in "ro". (It may have been 325 * changed to point to a gateway address, above.) 326 */ 327 dst = (struct sockaddr_in *)&ro->ro_dst; 328 /* 329 * See if the caller provided any multicast options 330 */ 331 if (imo != NULL) { 332 ip->ip_ttl = imo->imo_multicast_ttl; 333 if (imo->imo_multicast_vif != -1) 334 ip->ip_src.s_addr = 335 ip_mcast_src ? 336 ip_mcast_src(imo->imo_multicast_vif) : 337 INADDR_ANY; 338 } else 339 ip->ip_ttl = IP_DEFAULT_MULTICAST_TTL; 340 /* 341 * Confirm that the outgoing interface supports multicast. 342 */ 343 if ((imo == NULL) || (imo->imo_multicast_vif == -1)) { 344 if ((ifp->if_flags & IFF_MULTICAST) == 0) { 345 ipstat.ips_noroute++; 346 error = ENETUNREACH; 347 goto bad; 348 } 349 } 350 /* 351 * If source address not specified yet, use address 352 * of outgoing interface. 353 */ 354 if (ip->ip_src.s_addr == INADDR_ANY) { 355 /* Interface may have no addresses. */ 356 if (ia != NULL) 357 ip->ip_src = IA_SIN(ia)->sin_addr; 358 } 359 360 if (ip_mrouter && (flags & IP_FORWARDING) == 0) { 361 /* 362 * XXX 363 * delayed checksums are not currently 364 * compatible with IP multicast routing 365 */ 366 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) { 367 in_delayed_cksum(m); 368 m->m_pkthdr.csum_flags &= 369 ~CSUM_DELAY_DATA; 370 } 371 } 372 IN_LOOKUP_MULTI(pkt_dst, ifp, inm); 373 if (inm != NULL && 374 (imo == NULL || imo->imo_multicast_loop)) { 375 /* 376 * If we belong to the destination multicast group 377 * on the outgoing interface, and the caller did not 378 * forbid loopback, loop back a copy. 379 */ 380 ip_mloopback(ifp, m, dst, hlen); 381 } 382 else { 383 /* 384 * If we are acting as a multicast router, perform 385 * multicast forwarding as if the packet had just 386 * arrived on the interface to which we are about 387 * to send. The multicast forwarding function 388 * recursively calls this function, using the 389 * IP_FORWARDING flag to prevent infinite recursion. 390 * 391 * Multicasts that are looped back by ip_mloopback(), 392 * above, will be forwarded by the ip_input() routine, 393 * if necessary. 394 */ 395 if (ip_mrouter && (flags & IP_FORWARDING) == 0) { 396 /* 397 * If rsvp daemon is not running, do not 398 * set ip_moptions. This ensures that the packet 399 * is multicast and not just sent down one link 400 * as prescribed by rsvpd. 401 */ 402 if (!rsvp_on) 403 imo = NULL; 404 if (ip_mforward && 405 ip_mforward(ip, ifp, m, imo) != 0) { 406 m_freem(m); 407 goto done; 408 } 409 } 410 } 411 412 /* 413 * Multicasts with a time-to-live of zero may be looped- 414 * back, above, but must not be transmitted on a network. 415 * Also, multicasts addressed to the loopback interface 416 * are not sent -- the above call to ip_mloopback() will 417 * loop back a copy if this host actually belongs to the 418 * destination group on the loopback interface. 419 */ 420 if (ip->ip_ttl == 0 || ifp->if_flags & IFF_LOOPBACK) { 421 m_freem(m); 422 goto done; 423 } 424 425 goto sendit; 426 } 427 #ifndef notdef 428 /* 429 * If the source address is not specified yet, use the address 430 * of the outoing interface. In case, keep note we did that, so 431 * if the the firewall changes the next-hop causing the output 432 * interface to change, we can fix that. 433 */ 434 if (ip->ip_src.s_addr == INADDR_ANY) { 435 /* Interface may have no addresses. */ 436 if (ia != NULL) { 437 ip->ip_src = IA_SIN(ia)->sin_addr; 438 src_was_INADDR_ANY = 1; 439 } 440 } 441 #endif /* notdef */ 442 /* 443 * Verify that we have any chance at all of being able to queue 444 * the packet or packet fragments 445 */ 446 if ((ifp->if_snd.ifq_len + ip->ip_len / ifp->if_mtu + 1) >= 447 ifp->if_snd.ifq_maxlen) { 448 error = ENOBUFS; 449 ipstat.ips_odropped++; 450 goto bad; 451 } 452 453 /* 454 * Look for broadcast address and 455 * verify user is allowed to send 456 * such a packet. 457 */ 458 if (isbroadcast) { 459 if ((ifp->if_flags & IFF_BROADCAST) == 0) { 460 error = EADDRNOTAVAIL; 461 goto bad; 462 } 463 if ((flags & IP_ALLOWBROADCAST) == 0) { 464 error = EACCES; 465 goto bad; 466 } 467 /* don't allow broadcast messages to be fragmented */ 468 if ((u_short)ip->ip_len > ifp->if_mtu) { 469 error = EMSGSIZE; 470 goto bad; 471 } 472 m->m_flags |= M_BCAST; 473 } else { 474 m->m_flags &= ~M_BCAST; 475 } 476 477 sendit: 478 #ifdef IPSEC 479 /* get SP for this packet */ 480 if (inp == NULL) 481 sp = ipsec4_getpolicybyaddr(m, IPSEC_DIR_OUTBOUND, flags, &error); 482 else 483 sp = ipsec4_getpolicybypcb(m, IPSEC_DIR_OUTBOUND, inp, &error); 484 485 if (sp == NULL) { 486 ipsecstat.out_inval++; 487 goto bad; 488 } 489 490 error = 0; 491 492 /* check policy */ 493 switch (sp->policy) { 494 case IPSEC_POLICY_DISCARD: 495 /* 496 * This packet is just discarded. 497 */ 498 ipsecstat.out_polvio++; 499 goto bad; 500 501 case IPSEC_POLICY_BYPASS: 502 case IPSEC_POLICY_NONE: 503 /* no need to do IPsec. */ 504 goto skip_ipsec; 505 506 case IPSEC_POLICY_IPSEC: 507 if (sp->req == NULL) { 508 /* acquire a policy */ 509 error = key_spdacquire(sp); 510 goto bad; 511 } 512 break; 513 514 case IPSEC_POLICY_ENTRUST: 515 default: 516 printf("ip_output: Invalid policy found. %d\n", sp->policy); 517 } 518 { 519 struct ipsec_output_state state; 520 bzero(&state, sizeof(state)); 521 state.m = m; 522 if (flags & IP_ROUTETOIF) { 523 state.ro = &iproute; 524 bzero(&iproute, sizeof(iproute)); 525 } else 526 state.ro = ro; 527 state.dst = (struct sockaddr *)dst; 528 529 ip->ip_sum = 0; 530 531 /* 532 * XXX 533 * delayed checksums are not currently compatible with IPsec 534 */ 535 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) { 536 in_delayed_cksum(m); 537 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA; 538 } 539 540 ip->ip_len = htons(ip->ip_len); 541 ip->ip_off = htons(ip->ip_off); 542 543 error = ipsec4_output(&state, sp, flags); 544 545 m = state.m; 546 if (flags & IP_ROUTETOIF) { 547 /* 548 * if we have tunnel mode SA, we may need to ignore 549 * IP_ROUTETOIF. 550 */ 551 if (state.ro != &iproute || state.ro->ro_rt != NULL) { 552 flags &= ~IP_ROUTETOIF; 553 ro = state.ro; 554 } 555 } else 556 ro = state.ro; 557 dst = (struct sockaddr_in *)state.dst; 558 if (error) { 559 /* mbuf is already reclaimed in ipsec4_output. */ 560 m0 = NULL; 561 switch (error) { 562 case EHOSTUNREACH: 563 case ENETUNREACH: 564 case EMSGSIZE: 565 case ENOBUFS: 566 case ENOMEM: 567 break; 568 default: 569 printf("ip4_output (ipsec): error code %d\n", error); 570 /*fall through*/ 571 case ENOENT: 572 /* don't show these error codes to the user */ 573 error = 0; 574 break; 575 } 576 goto bad; 577 } 578 } 579 580 /* be sure to update variables that are affected by ipsec4_output() */ 581 ip = mtod(m, struct ip *); 582 hlen = ip->ip_hl << 2; 583 if (ro->ro_rt == NULL) { 584 if ((flags & IP_ROUTETOIF) == 0) { 585 printf("ip_output: " 586 "can't update route after IPsec processing\n"); 587 error = EHOSTUNREACH; /*XXX*/ 588 goto bad; 589 } 590 } else { 591 ia = ifatoia(ro->ro_rt->rt_ifa); 592 ifp = ro->ro_rt->rt_ifp; 593 } 594 595 /* make it flipped, again. */ 596 ip->ip_len = ntohs(ip->ip_len); 597 ip->ip_off = ntohs(ip->ip_off); 598 skip_ipsec: 599 #endif /*IPSEC*/ 600 #ifdef FAST_IPSEC 601 /* 602 * Check the security policy (SP) for the packet and, if 603 * required, do IPsec-related processing. There are two 604 * cases here; the first time a packet is sent through 605 * it will be untagged and handled by ipsec4_checkpolicy. 606 * If the packet is resubmitted to ip_output (e.g. after 607 * AH, ESP, etc. processing), there will be a tag to bypass 608 * the lookup and related policy checking. 609 */ 610 mtag = m_tag_find(m, PACKET_TAG_IPSEC_PENDING_TDB, NULL); 611 s = splnet(); 612 if (mtag != NULL) { 613 tdbi = (struct tdb_ident *)(mtag + 1); 614 sp = ipsec_getpolicy(tdbi, IPSEC_DIR_OUTBOUND); 615 if (sp == NULL) 616 error = -EINVAL; /* force silent drop */ 617 m_tag_delete(m, mtag); 618 } else { 619 sp = ipsec4_checkpolicy(m, IPSEC_DIR_OUTBOUND, flags, 620 &error, inp); 621 } 622 /* 623 * There are four return cases: 624 * sp != NULL apply IPsec policy 625 * sp == NULL, error == 0 no IPsec handling needed 626 * sp == NULL, error == -EINVAL discard packet w/o error 627 * sp == NULL, error != 0 discard packet, report error 628 */ 629 if (sp != NULL) { 630 /* Loop detection, check if ipsec processing already done */ 631 KASSERT(sp->req != NULL, ("ip_output: no ipsec request")); 632 for (mtag = m_tag_first(m); mtag != NULL; 633 mtag = m_tag_next(m, mtag)) { 634 if (mtag->m_tag_cookie != MTAG_ABI_COMPAT) 635 continue; 636 if (mtag->m_tag_id != PACKET_TAG_IPSEC_OUT_DONE && 637 mtag->m_tag_id != PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED) 638 continue; 639 /* 640 * Check if policy has an SA associated with it. 641 * This can happen when an SP has yet to acquire 642 * an SA; e.g. on first reference. If it occurs, 643 * then we let ipsec4_process_packet do its thing. 644 */ 645 if (sp->req->sav == NULL) 646 break; 647 tdbi = (struct tdb_ident *)(mtag + 1); 648 if (tdbi->spi == sp->req->sav->spi && 649 tdbi->proto == sp->req->sav->sah->saidx.proto && 650 bcmp(&tdbi->dst, &sp->req->sav->sah->saidx.dst, 651 sizeof (union sockaddr_union)) == 0) { 652 /* 653 * No IPsec processing is needed, free 654 * reference to SP. 655 * 656 * NB: null pointer to avoid free at 657 * done: below. 658 */ 659 KEY_FREESP(&sp), sp = NULL; 660 splx(s); 661 goto spd_done; 662 } 663 } 664 665 /* 666 * Do delayed checksums now because we send before 667 * this is done in the normal processing path. 668 */ 669 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) { 670 in_delayed_cksum(m); 671 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA; 672 } 673 674 ip->ip_len = htons(ip->ip_len); 675 ip->ip_off = htons(ip->ip_off); 676 677 /* NB: callee frees mbuf */ 678 error = ipsec4_process_packet(m, sp->req, flags, 0); 679 /* 680 * Preserve KAME behaviour: ENOENT can be returned 681 * when an SA acquire is in progress. Don't propagate 682 * this to user-level; it confuses applications. 683 * 684 * XXX this will go away when the SADB is redone. 685 */ 686 if (error == ENOENT) 687 error = 0; 688 splx(s); 689 goto done; 690 } else { 691 splx(s); 692 693 if (error != 0) { 694 /* 695 * Hack: -EINVAL is used to signal that a packet 696 * should be silently discarded. This is typically 697 * because we asked key management for an SA and 698 * it was delayed (e.g. kicked up to IKE). 699 */ 700 if (error == -EINVAL) 701 error = 0; 702 goto bad; 703 } else { 704 /* No IPsec processing for this packet. */ 705 } 706 #ifdef notyet 707 /* 708 * If deferred crypto processing is needed, check that 709 * the interface supports it. 710 */ 711 mtag = m_tag_find(m, PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED, NULL); 712 if (mtag != NULL && (ifp->if_capenable & IFCAP_IPSEC) == 0) { 713 /* notify IPsec to do its own crypto */ 714 ipsp_skipcrypto_unmark((struct tdb_ident *)(mtag + 1)); 715 error = EHOSTUNREACH; 716 goto bad; 717 } 718 #endif 719 } 720 spd_done: 721 #endif /* FAST_IPSEC */ 722 723 /* 724 * IpHack's section. 725 * - Xlate: translate packet's addr/port (NAT). 726 * - Firewall: deny/allow/etc. 727 * - Wrap: fake packet's addr/port <unimpl.> 728 * - Encapsulate: put it in another IP and send out. <unimp.> 729 */ 730 #ifdef PFIL_HOOKS 731 /* 732 * Run through list of hooks for output packets. 733 */ 734 m1 = m; 735 pfh = pfil_hook_get(PFIL_OUT, &inetsw[ip_protox[IPPROTO_IP]].pr_pfh); 736 for (; pfh; pfh = TAILQ_NEXT(pfh, pfil_link)) 737 if (pfh->pfil_func) { 738 rv = pfh->pfil_func(ip, hlen, ifp, 1, &m1); 739 if (rv) { 740 error = EHOSTUNREACH; 741 goto done; 742 } 743 m = m1; 744 if (m == NULL) 745 goto done; 746 ip = mtod(m, struct ip *); 747 } 748 #endif /* PFIL_HOOKS */ 749 750 /* 751 * Check with the firewall... 752 * but not if we are already being fwd'd from a firewall. 753 */ 754 if (fw_enable && IPFW_LOADED && !args.next_hop) { 755 struct sockaddr_in *old = dst; 756 757 args.m = m; 758 args.next_hop = dst; 759 args.oif = ifp; 760 off = ip_fw_chk_ptr(&args); 761 m = args.m; 762 dst = args.next_hop; 763 764 /* 765 * On return we must do the following: 766 * m == NULL -> drop the pkt (old interface, deprecated) 767 * (off & IP_FW_PORT_DENY_FLAG) -> drop the pkt (new interface) 768 * 1<=off<= 0xffff -> DIVERT 769 * (off & IP_FW_PORT_DYNT_FLAG) -> send to a DUMMYNET pipe 770 * (off & IP_FW_PORT_TEE_FLAG) -> TEE the packet 771 * dst != old -> IPFIREWALL_FORWARD 772 * off==0, dst==old -> accept 773 * If some of the above modules are not compiled in, then 774 * we should't have to check the corresponding condition 775 * (because the ipfw control socket should not accept 776 * unsupported rules), but better play safe and drop 777 * packets in case of doubt. 778 */ 779 if ( (off & IP_FW_PORT_DENY_FLAG) || m == NULL) { 780 if (m) 781 m_freem(m); 782 error = EACCES; 783 goto done; 784 } 785 ip = mtod(m, struct ip *); 786 if (off == 0 && dst == old) /* common case */ 787 goto pass; 788 if (DUMMYNET_LOADED && (off & IP_FW_PORT_DYNT_FLAG) != 0) { 789 /* 790 * pass the pkt to dummynet. Need to include 791 * pipe number, m, ifp, ro, dst because these are 792 * not recomputed in the next pass. 793 * All other parameters have been already used and 794 * so they are not needed anymore. 795 * XXX note: if the ifp or ro entry are deleted 796 * while a pkt is in dummynet, we are in trouble! 797 */ 798 args.ro = ro; 799 args.dst = dst; 800 args.flags = flags; 801 802 error = ip_dn_io_ptr(m, off & 0xffff, DN_TO_IP_OUT, 803 &args); 804 goto done; 805 } 806 #ifdef IPDIVERT 807 if (off != 0 && (off & IP_FW_PORT_DYNT_FLAG) == 0) { 808 struct mbuf *clone = NULL; 809 810 /* Clone packet if we're doing a 'tee' */ 811 if ((off & IP_FW_PORT_TEE_FLAG) != 0) 812 clone = m_dup(m, M_DONTWAIT); 813 814 /* 815 * XXX 816 * delayed checksums are not currently compatible 817 * with divert sockets. 818 */ 819 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) { 820 in_delayed_cksum(m); 821 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA; 822 } 823 824 /* Restore packet header fields to original values */ 825 ip->ip_len = htons(ip->ip_len); 826 ip->ip_off = htons(ip->ip_off); 827 828 /* Deliver packet to divert input routine */ 829 divert_packet(m, 0, off & 0xffff, args.divert_rule); 830 831 /* If 'tee', continue with original packet */ 832 if (clone != NULL) { 833 m = clone; 834 ip = mtod(m, struct ip *); 835 goto pass; 836 } 837 goto done; 838 } 839 #endif 840 841 /* IPFIREWALL_FORWARD */ 842 /* 843 * Check dst to make sure it is directly reachable on the 844 * interface we previously thought it was. 845 * If it isn't (which may be likely in some situations) we have 846 * to re-route it (ie, find a route for the next-hop and the 847 * associated interface) and set them here. This is nested 848 * forwarding which in most cases is undesirable, except where 849 * such control is nigh impossible. So we do it here. 850 * And I'm babbling. 851 */ 852 if (off == 0 && old != dst) { /* FORWARD, dst has changed */ 853 #if 0 854 /* 855 * XXX To improve readability, this block should be 856 * changed into a function call as below: 857 */ 858 error = ip_ipforward(&m, &dst, &ifp); 859 if (error) 860 goto bad; 861 if (m == NULL) /* ip_input consumed the mbuf */ 862 goto done; 863 #else 864 struct in_ifaddr *ia; 865 866 /* 867 * XXX sro_fwd below is static, and a pointer 868 * to it gets passed to routines downstream. 869 * This could have surprisingly bad results in 870 * practice, because its content is overwritten 871 * by subsequent packets. 872 */ 873 /* There must be a better way to do this next line... */ 874 static struct route sro_fwd; 875 struct route *ro_fwd = &sro_fwd; 876 877 #if 0 878 print_ip("IPFIREWALL_FORWARD: New dst ip: ", 879 dst->sin_addr, "\n"); 880 #endif 881 882 /* 883 * We need to figure out if we have been forwarded 884 * to a local socket. If so, then we should somehow 885 * "loop back" to ip_input, and get directed to the 886 * PCB as if we had received this packet. This is 887 * because it may be dificult to identify the packets 888 * you want to forward until they are being output 889 * and have selected an interface. (e.g. locally 890 * initiated packets) If we used the loopback inteface, 891 * we would not be able to control what happens 892 * as the packet runs through ip_input() as 893 * it is done through an ISR. 894 */ 895 LIST_FOREACH(ia, 896 INADDR_HASH(dst->sin_addr.s_addr), ia_hash) { 897 /* 898 * If the addr to forward to is one 899 * of ours, we pretend to 900 * be the destination for this packet. 901 */ 902 if (IA_SIN(ia)->sin_addr.s_addr == 903 dst->sin_addr.s_addr) 904 break; 905 } 906 if (ia) { /* tell ip_input "dont filter" */ 907 struct m_hdr tag; 908 909 tag.mh_type = MT_TAG; 910 tag.mh_flags = PACKET_TAG_IPFORWARD; 911 tag.mh_data = (caddr_t)args.next_hop; 912 tag.mh_next = m; 913 914 if (m->m_pkthdr.rcvif == NULL) 915 m->m_pkthdr.rcvif = ifunit("lo0"); 916 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) { 917 m->m_pkthdr.csum_flags |= 918 CSUM_DATA_VALID | CSUM_PSEUDO_HDR; 919 m0->m_pkthdr.csum_data = 0xffff; 920 } 921 m->m_pkthdr.csum_flags |= 922 CSUM_IP_CHECKED | CSUM_IP_VALID; 923 ip->ip_len = htons(ip->ip_len); 924 ip->ip_off = htons(ip->ip_off); 925 ip_input((struct mbuf *)&tag); 926 goto done; 927 } 928 /* Some of the logic for this was 929 * nicked from above. 930 * 931 * This rewrites the cached route in a local PCB. 932 * Is this what we want to do? 933 */ 934 bcopy(dst, &ro_fwd->ro_dst, sizeof(*dst)); 935 936 ro_fwd->ro_rt = 0; 937 rtalloc_ign(ro_fwd, RTF_PRCLONING); 938 939 if (ro_fwd->ro_rt == 0) { 940 ipstat.ips_noroute++; 941 error = EHOSTUNREACH; 942 goto bad; 943 } 944 945 ia = ifatoia(ro_fwd->ro_rt->rt_ifa); 946 ifp = ro_fwd->ro_rt->rt_ifp; 947 ro_fwd->ro_rt->rt_use++; 948 if (ro_fwd->ro_rt->rt_flags & RTF_GATEWAY) 949 dst = (struct sockaddr_in *) 950 ro_fwd->ro_rt->rt_gateway; 951 if (ro_fwd->ro_rt->rt_flags & RTF_HOST) 952 isbroadcast = 953 (ro_fwd->ro_rt->rt_flags & RTF_BROADCAST); 954 else 955 isbroadcast = in_broadcast(dst->sin_addr, ifp); 956 if (ro->ro_rt) 957 RTFREE(ro->ro_rt); 958 ro->ro_rt = ro_fwd->ro_rt; 959 dst = (struct sockaddr_in *)&ro_fwd->ro_dst; 960 961 #endif /* ... block to be put into a function */ 962 /* 963 * If we added a default src ip earlier, 964 * which would have been gotten from the-then 965 * interface, do it again, from the new one. 966 */ 967 if (src_was_INADDR_ANY) 968 ip->ip_src = IA_SIN(ia)->sin_addr; 969 goto pass ; 970 } 971 972 /* 973 * if we get here, none of the above matches, and 974 * we have to drop the pkt 975 */ 976 m_freem(m); 977 error = EACCES; /* not sure this is the right error msg */ 978 goto done; 979 } 980 981 pass: 982 /* 127/8 must not appear on wire - RFC1122. */ 983 if ((ntohl(ip->ip_dst.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET || 984 (ntohl(ip->ip_src.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET) { 985 if ((ifp->if_flags & IFF_LOOPBACK) == 0) { 986 ipstat.ips_badaddr++; 987 error = EADDRNOTAVAIL; 988 goto bad; 989 } 990 } 991 992 m->m_pkthdr.csum_flags |= CSUM_IP; 993 sw_csum = m->m_pkthdr.csum_flags & ~ifp->if_hwassist; 994 if (sw_csum & CSUM_DELAY_DATA) { 995 in_delayed_cksum(m); 996 sw_csum &= ~CSUM_DELAY_DATA; 997 } 998 m->m_pkthdr.csum_flags &= ifp->if_hwassist; 999 1000 /* 1001 * If small enough for interface, or the interface will take 1002 * care of the fragmentation for us, can just send directly. 1003 */ 1004 if ((u_short)ip->ip_len <= ifp->if_mtu || 1005 ifp->if_hwassist & CSUM_FRAGMENT) { 1006 ip->ip_len = htons(ip->ip_len); 1007 ip->ip_off = htons(ip->ip_off); 1008 ip->ip_sum = 0; 1009 if (sw_csum & CSUM_DELAY_IP) 1010 ip->ip_sum = in_cksum(m, hlen); 1011 1012 /* Record statistics for this interface address. */ 1013 if (!(flags & IP_FORWARDING) && ia) { 1014 ia->ia_ifa.if_opackets++; 1015 ia->ia_ifa.if_obytes += m->m_pkthdr.len; 1016 } 1017 1018 #ifdef IPSEC 1019 /* clean ipsec history once it goes out of the node */ 1020 ipsec_delaux(m); 1021 #endif 1022 1023 #ifdef MBUF_STRESS_TEST 1024 if (mbuf_frag_size && m->m_pkthdr.len > mbuf_frag_size) { 1025 struct mbuf *m1, *m2; 1026 int length, tmp; 1027 1028 tmp = length = m->m_pkthdr.len; 1029 1030 while ((length -= mbuf_frag_size) >= 1) { 1031 m1 = m_split(m, length, M_DONTWAIT); 1032 if (m1 == NULL) 1033 break; 1034 m1->m_flags &= ~M_PKTHDR; 1035 m2 = m; 1036 while (m2->m_next != NULL) 1037 m2 = m2->m_next; 1038 m2->m_next = m1; 1039 } 1040 m->m_pkthdr.len = tmp; 1041 } 1042 #endif 1043 error = (*ifp->if_output)(ifp, m, 1044 (struct sockaddr *)dst, ro->ro_rt); 1045 goto done; 1046 } 1047 /* 1048 * Too large for interface; fragment if possible. 1049 * Must be able to put at least 8 bytes per fragment. 1050 */ 1051 if (ip->ip_off & IP_DF) { 1052 error = EMSGSIZE; 1053 /* 1054 * This case can happen if the user changed the MTU 1055 * of an interface after enabling IP on it. Because 1056 * most netifs don't keep track of routes pointing to 1057 * them, there is no way for one to update all its 1058 * routes when the MTU is changed. 1059 */ 1060 if ((ro->ro_rt->rt_flags & (RTF_UP | RTF_HOST)) 1061 && !(ro->ro_rt->rt_rmx.rmx_locks & RTV_MTU) 1062 && (ro->ro_rt->rt_rmx.rmx_mtu > ifp->if_mtu)) { 1063 ro->ro_rt->rt_rmx.rmx_mtu = ifp->if_mtu; 1064 } 1065 ipstat.ips_cantfrag++; 1066 goto bad; 1067 } 1068 len = (ifp->if_mtu - hlen) &~ 7; 1069 if (len < 8) { 1070 error = EMSGSIZE; 1071 goto bad; 1072 } 1073 1074 /* 1075 * if the interface will not calculate checksums on 1076 * fragmented packets, then do it here. 1077 */ 1078 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA && 1079 (ifp->if_hwassist & CSUM_IP_FRAGS) == 0) { 1080 in_delayed_cksum(m); 1081 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA; 1082 } 1083 1084 if (len > PAGE_SIZE) { 1085 /* 1086 * Fragement large datagrams such that each segment 1087 * contains a multiple of PAGE_SIZE amount of data, 1088 * plus headers. This enables a receiver to perform 1089 * page-flipping zero-copy optimizations. 1090 */ 1091 1092 int newlen; 1093 struct mbuf *mtmp; 1094 1095 for (mtmp = m, off = 0; 1096 mtmp && ((off + mtmp->m_len) <= ifp->if_mtu); 1097 mtmp = mtmp->m_next) { 1098 off += mtmp->m_len; 1099 } 1100 /* 1101 * firstlen (off - hlen) must be aligned on an 1102 * 8-byte boundary 1103 */ 1104 if (off < hlen) 1105 goto smart_frag_failure; 1106 off = ((off - hlen) & ~7) + hlen; 1107 newlen = (~PAGE_MASK) & ifp->if_mtu; 1108 if ((newlen + sizeof (struct ip)) > ifp->if_mtu) { 1109 /* we failed, go back the default */ 1110 smart_frag_failure: 1111 newlen = len; 1112 off = hlen + len; 1113 } 1114 1115 /* printf("ipfrag: len = %d, hlen = %d, mhlen = %d, newlen = %d, off = %d\n", 1116 len, hlen, sizeof (struct ip), newlen, off);*/ 1117 1118 len = newlen; 1119 1120 } else { 1121 off = hlen + len; 1122 } 1123 1124 1125 1126 { 1127 int mhlen, firstlen = off - hlen; 1128 struct mbuf **mnext = &m->m_nextpkt; 1129 int nfrags = 1; 1130 1131 /* 1132 * Loop through length of segment after first fragment, 1133 * make new header and copy data of each part and link onto chain. 1134 */ 1135 m0 = m; 1136 mhlen = sizeof (struct ip); 1137 for (; off < (u_short)ip->ip_len; off += len) { 1138 MGETHDR(m, M_DONTWAIT, MT_HEADER); 1139 if (m == 0) { 1140 error = ENOBUFS; 1141 ipstat.ips_odropped++; 1142 goto sendorfree; 1143 } 1144 m->m_flags |= (m0->m_flags & M_MCAST) | M_FRAG; 1145 m->m_data += max_linkhdr; 1146 mhip = mtod(m, struct ip *); 1147 *mhip = *ip; 1148 if (hlen > sizeof (struct ip)) { 1149 mhlen = ip_optcopy(ip, mhip) + sizeof (struct ip); 1150 mhip->ip_v = IPVERSION; 1151 mhip->ip_hl = mhlen >> 2; 1152 } 1153 m->m_len = mhlen; 1154 mhip->ip_off = ((off - hlen) >> 3) + ip->ip_off; 1155 if (off + len >= (u_short)ip->ip_len) 1156 len = (u_short)ip->ip_len - off; 1157 else 1158 mhip->ip_off |= IP_MF; 1159 mhip->ip_len = htons((u_short)(len + mhlen)); 1160 m->m_next = m_copy(m0, off, len); 1161 if (m->m_next == 0) { 1162 (void) m_free(m); 1163 error = ENOBUFS; /* ??? */ 1164 ipstat.ips_odropped++; 1165 goto sendorfree; 1166 } 1167 m->m_pkthdr.len = mhlen + len; 1168 m->m_pkthdr.rcvif = (struct ifnet *)0; 1169 #ifdef MAC 1170 mac_create_fragment(m0, m); 1171 #endif 1172 m->m_pkthdr.csum_flags = m0->m_pkthdr.csum_flags; 1173 mhip->ip_off = htons(mhip->ip_off); 1174 mhip->ip_sum = 0; 1175 if (sw_csum & CSUM_DELAY_IP) 1176 mhip->ip_sum = in_cksum(m, mhlen); 1177 *mnext = m; 1178 mnext = &m->m_nextpkt; 1179 nfrags++; 1180 } 1181 ipstat.ips_ofragments += nfrags; 1182 1183 /* set first/last markers for fragment chain */ 1184 m->m_flags |= M_LASTFRAG; 1185 m0->m_flags |= M_FIRSTFRAG | M_FRAG; 1186 m0->m_pkthdr.csum_data = nfrags; 1187 1188 /* 1189 * Update first fragment by trimming what's been copied out 1190 * and updating header, then send each fragment (in order). 1191 */ 1192 m = m0; 1193 m_adj(m, hlen + firstlen - (u_short)ip->ip_len); 1194 m->m_pkthdr.len = hlen + firstlen; 1195 ip->ip_len = htons((u_short)m->m_pkthdr.len); 1196 ip->ip_off |= IP_MF; 1197 ip->ip_off = htons(ip->ip_off); 1198 ip->ip_sum = 0; 1199 if (sw_csum & CSUM_DELAY_IP) 1200 ip->ip_sum = in_cksum(m, hlen); 1201 sendorfree: 1202 for (m = m0; m; m = m0) { 1203 m0 = m->m_nextpkt; 1204 m->m_nextpkt = 0; 1205 #ifdef IPSEC 1206 /* clean ipsec history once it goes out of the node */ 1207 ipsec_delaux(m); 1208 #endif 1209 if (error == 0) { 1210 /* Record statistics for this interface address. */ 1211 if (ia != NULL) { 1212 ia->ia_ifa.if_opackets++; 1213 ia->ia_ifa.if_obytes += m->m_pkthdr.len; 1214 } 1215 1216 error = (*ifp->if_output)(ifp, m, 1217 (struct sockaddr *)dst, ro->ro_rt); 1218 } else 1219 m_freem(m); 1220 } 1221 1222 if (error == 0) 1223 ipstat.ips_fragmented++; 1224 } 1225 done: 1226 #ifdef IPSEC 1227 if (ro == &iproute && ro->ro_rt) { 1228 RTFREE(ro->ro_rt); 1229 ro->ro_rt = NULL; 1230 } 1231 if (sp != NULL) { 1232 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 1233 printf("DP ip_output call free SP:%p\n", sp)); 1234 key_freesp(sp); 1235 } 1236 #endif /* IPSEC */ 1237 #ifdef FAST_IPSEC 1238 if (ro == &iproute && ro->ro_rt) { 1239 RTFREE(ro->ro_rt); 1240 ro->ro_rt = NULL; 1241 } 1242 if (sp != NULL) 1243 KEY_FREESP(&sp); 1244 #endif /* FAST_IPSEC */ 1245 return (error); 1246 bad: 1247 m_freem(m); 1248 goto done; 1249 } 1250 1251 void 1252 in_delayed_cksum(struct mbuf *m) 1253 { 1254 struct ip *ip; 1255 u_short csum, offset; 1256 1257 ip = mtod(m, struct ip *); 1258 offset = ip->ip_hl << 2 ; 1259 csum = in_cksum_skip(m, ip->ip_len, offset); 1260 if (m->m_pkthdr.csum_flags & CSUM_UDP && csum == 0) 1261 csum = 0xffff; 1262 offset += m->m_pkthdr.csum_data; /* checksum offset */ 1263 1264 if (offset + sizeof(u_short) > m->m_len) { 1265 printf("delayed m_pullup, m->len: %d off: %d p: %d\n", 1266 m->m_len, offset, ip->ip_p); 1267 /* 1268 * XXX 1269 * this shouldn't happen, but if it does, the 1270 * correct behavior may be to insert the checksum 1271 * in the existing chain instead of rearranging it. 1272 */ 1273 m = m_pullup(m, offset + sizeof(u_short)); 1274 } 1275 *(u_short *)(m->m_data + offset) = csum; 1276 } 1277 1278 /* 1279 * Insert IP options into preformed packet. 1280 * Adjust IP destination as required for IP source routing, 1281 * as indicated by a non-zero in_addr at the start of the options. 1282 * 1283 * XXX This routine assumes that the packet has no options in place. 1284 */ 1285 static struct mbuf * 1286 ip_insertoptions(m, opt, phlen) 1287 register struct mbuf *m; 1288 struct mbuf *opt; 1289 int *phlen; 1290 { 1291 register struct ipoption *p = mtod(opt, struct ipoption *); 1292 struct mbuf *n; 1293 register struct ip *ip = mtod(m, struct ip *); 1294 unsigned optlen; 1295 1296 optlen = opt->m_len - sizeof(p->ipopt_dst); 1297 if (optlen + (u_short)ip->ip_len > IP_MAXPACKET) { 1298 *phlen = 0; 1299 return (m); /* XXX should fail */ 1300 } 1301 if (p->ipopt_dst.s_addr) 1302 ip->ip_dst = p->ipopt_dst; 1303 if (m->m_flags & M_EXT || m->m_data - optlen < m->m_pktdat) { 1304 MGETHDR(n, M_DONTWAIT, MT_HEADER); 1305 if (n == 0) { 1306 *phlen = 0; 1307 return (m); 1308 } 1309 n->m_pkthdr.rcvif = (struct ifnet *)0; 1310 #ifdef MAC 1311 mac_create_mbuf_from_mbuf(m, n); 1312 #endif 1313 n->m_pkthdr.len = m->m_pkthdr.len + optlen; 1314 m->m_len -= sizeof(struct ip); 1315 m->m_data += sizeof(struct ip); 1316 n->m_next = m; 1317 m = n; 1318 m->m_len = optlen + sizeof(struct ip); 1319 m->m_data += max_linkhdr; 1320 bcopy(ip, mtod(m, void *), sizeof(struct ip)); 1321 } else { 1322 m->m_data -= optlen; 1323 m->m_len += optlen; 1324 m->m_pkthdr.len += optlen; 1325 bcopy(ip, mtod(m, void *), sizeof(struct ip)); 1326 } 1327 ip = mtod(m, struct ip *); 1328 bcopy(p->ipopt_list, ip + 1, optlen); 1329 *phlen = sizeof(struct ip) + optlen; 1330 ip->ip_v = IPVERSION; 1331 ip->ip_hl = *phlen >> 2; 1332 ip->ip_len += optlen; 1333 return (m); 1334 } 1335 1336 /* 1337 * Copy options from ip to jp, 1338 * omitting those not copied during fragmentation. 1339 */ 1340 int 1341 ip_optcopy(ip, jp) 1342 struct ip *ip, *jp; 1343 { 1344 register u_char *cp, *dp; 1345 int opt, optlen, cnt; 1346 1347 cp = (u_char *)(ip + 1); 1348 dp = (u_char *)(jp + 1); 1349 cnt = (ip->ip_hl << 2) - sizeof (struct ip); 1350 for (; cnt > 0; cnt -= optlen, cp += optlen) { 1351 opt = cp[0]; 1352 if (opt == IPOPT_EOL) 1353 break; 1354 if (opt == IPOPT_NOP) { 1355 /* Preserve for IP mcast tunnel's LSRR alignment. */ 1356 *dp++ = IPOPT_NOP; 1357 optlen = 1; 1358 continue; 1359 } 1360 1361 KASSERT(cnt >= IPOPT_OLEN + sizeof(*cp), 1362 ("ip_optcopy: malformed ipv4 option")); 1363 optlen = cp[IPOPT_OLEN]; 1364 KASSERT(optlen >= IPOPT_OLEN + sizeof(*cp) && optlen <= cnt, 1365 ("ip_optcopy: malformed ipv4 option")); 1366 1367 /* bogus lengths should have been caught by ip_dooptions */ 1368 if (optlen > cnt) 1369 optlen = cnt; 1370 if (IPOPT_COPIED(opt)) { 1371 bcopy(cp, dp, optlen); 1372 dp += optlen; 1373 } 1374 } 1375 for (optlen = dp - (u_char *)(jp+1); optlen & 0x3; optlen++) 1376 *dp++ = IPOPT_EOL; 1377 return (optlen); 1378 } 1379 1380 /* 1381 * IP socket option processing. 1382 */ 1383 int 1384 ip_ctloutput(so, sopt) 1385 struct socket *so; 1386 struct sockopt *sopt; 1387 { 1388 struct inpcb *inp = sotoinpcb(so); 1389 int error, optval; 1390 1391 error = optval = 0; 1392 if (sopt->sopt_level != IPPROTO_IP) { 1393 return (EINVAL); 1394 } 1395 1396 switch (sopt->sopt_dir) { 1397 case SOPT_SET: 1398 switch (sopt->sopt_name) { 1399 case IP_OPTIONS: 1400 #ifdef notyet 1401 case IP_RETOPTS: 1402 #endif 1403 { 1404 struct mbuf *m; 1405 if (sopt->sopt_valsize > MLEN) { 1406 error = EMSGSIZE; 1407 break; 1408 } 1409 MGET(m, sopt->sopt_td ? M_TRYWAIT : M_DONTWAIT, MT_HEADER); 1410 if (m == 0) { 1411 error = ENOBUFS; 1412 break; 1413 } 1414 m->m_len = sopt->sopt_valsize; 1415 error = sooptcopyin(sopt, mtod(m, char *), m->m_len, 1416 m->m_len); 1417 1418 return (ip_pcbopts(sopt->sopt_name, &inp->inp_options, 1419 m)); 1420 } 1421 1422 case IP_TOS: 1423 case IP_TTL: 1424 case IP_RECVOPTS: 1425 case IP_RECVRETOPTS: 1426 case IP_RECVDSTADDR: 1427 case IP_RECVTTL: 1428 case IP_RECVIF: 1429 case IP_FAITH: 1430 error = sooptcopyin(sopt, &optval, sizeof optval, 1431 sizeof optval); 1432 if (error) 1433 break; 1434 1435 switch (sopt->sopt_name) { 1436 case IP_TOS: 1437 inp->inp_ip_tos = optval; 1438 break; 1439 1440 case IP_TTL: 1441 inp->inp_ip_ttl = optval; 1442 break; 1443 #define OPTSET(bit) \ 1444 if (optval) \ 1445 inp->inp_flags |= bit; \ 1446 else \ 1447 inp->inp_flags &= ~bit; 1448 1449 case IP_RECVOPTS: 1450 OPTSET(INP_RECVOPTS); 1451 break; 1452 1453 case IP_RECVRETOPTS: 1454 OPTSET(INP_RECVRETOPTS); 1455 break; 1456 1457 case IP_RECVDSTADDR: 1458 OPTSET(INP_RECVDSTADDR); 1459 break; 1460 1461 case IP_RECVTTL: 1462 OPTSET(INP_RECVTTL); 1463 break; 1464 1465 case IP_RECVIF: 1466 OPTSET(INP_RECVIF); 1467 break; 1468 1469 case IP_FAITH: 1470 OPTSET(INP_FAITH); 1471 break; 1472 } 1473 break; 1474 #undef OPTSET 1475 1476 case IP_MULTICAST_IF: 1477 case IP_MULTICAST_VIF: 1478 case IP_MULTICAST_TTL: 1479 case IP_MULTICAST_LOOP: 1480 case IP_ADD_MEMBERSHIP: 1481 case IP_DROP_MEMBERSHIP: 1482 error = ip_setmoptions(sopt, &inp->inp_moptions); 1483 break; 1484 1485 case IP_PORTRANGE: 1486 error = sooptcopyin(sopt, &optval, sizeof optval, 1487 sizeof optval); 1488 if (error) 1489 break; 1490 1491 switch (optval) { 1492 case IP_PORTRANGE_DEFAULT: 1493 inp->inp_flags &= ~(INP_LOWPORT); 1494 inp->inp_flags &= ~(INP_HIGHPORT); 1495 break; 1496 1497 case IP_PORTRANGE_HIGH: 1498 inp->inp_flags &= ~(INP_LOWPORT); 1499 inp->inp_flags |= INP_HIGHPORT; 1500 break; 1501 1502 case IP_PORTRANGE_LOW: 1503 inp->inp_flags &= ~(INP_HIGHPORT); 1504 inp->inp_flags |= INP_LOWPORT; 1505 break; 1506 1507 default: 1508 error = EINVAL; 1509 break; 1510 } 1511 break; 1512 1513 #if defined(IPSEC) || defined(FAST_IPSEC) 1514 case IP_IPSEC_POLICY: 1515 { 1516 caddr_t req; 1517 size_t len = 0; 1518 int priv; 1519 struct mbuf *m; 1520 int optname; 1521 1522 if ((error = soopt_getm(sopt, &m)) != 0) /* XXX */ 1523 break; 1524 if ((error = soopt_mcopyin(sopt, m)) != 0) /* XXX */ 1525 break; 1526 priv = (sopt->sopt_td != NULL && 1527 suser(sopt->sopt_td) != 0) ? 0 : 1; 1528 req = mtod(m, caddr_t); 1529 len = m->m_len; 1530 optname = sopt->sopt_name; 1531 error = ipsec4_set_policy(inp, optname, req, len, priv); 1532 m_freem(m); 1533 break; 1534 } 1535 #endif /*IPSEC*/ 1536 1537 default: 1538 error = ENOPROTOOPT; 1539 break; 1540 } 1541 break; 1542 1543 case SOPT_GET: 1544 switch (sopt->sopt_name) { 1545 case IP_OPTIONS: 1546 case IP_RETOPTS: 1547 if (inp->inp_options) 1548 error = sooptcopyout(sopt, 1549 mtod(inp->inp_options, 1550 char *), 1551 inp->inp_options->m_len); 1552 else 1553 sopt->sopt_valsize = 0; 1554 break; 1555 1556 case IP_TOS: 1557 case IP_TTL: 1558 case IP_RECVOPTS: 1559 case IP_RECVRETOPTS: 1560 case IP_RECVDSTADDR: 1561 case IP_RECVTTL: 1562 case IP_RECVIF: 1563 case IP_PORTRANGE: 1564 case IP_FAITH: 1565 switch (sopt->sopt_name) { 1566 1567 case IP_TOS: 1568 optval = inp->inp_ip_tos; 1569 break; 1570 1571 case IP_TTL: 1572 optval = inp->inp_ip_ttl; 1573 break; 1574 1575 #define OPTBIT(bit) (inp->inp_flags & bit ? 1 : 0) 1576 1577 case IP_RECVOPTS: 1578 optval = OPTBIT(INP_RECVOPTS); 1579 break; 1580 1581 case IP_RECVRETOPTS: 1582 optval = OPTBIT(INP_RECVRETOPTS); 1583 break; 1584 1585 case IP_RECVDSTADDR: 1586 optval = OPTBIT(INP_RECVDSTADDR); 1587 break; 1588 1589 case IP_RECVTTL: 1590 optval = OPTBIT(INP_RECVTTL); 1591 break; 1592 1593 case IP_RECVIF: 1594 optval = OPTBIT(INP_RECVIF); 1595 break; 1596 1597 case IP_PORTRANGE: 1598 if (inp->inp_flags & INP_HIGHPORT) 1599 optval = IP_PORTRANGE_HIGH; 1600 else if (inp->inp_flags & INP_LOWPORT) 1601 optval = IP_PORTRANGE_LOW; 1602 else 1603 optval = 0; 1604 break; 1605 1606 case IP_FAITH: 1607 optval = OPTBIT(INP_FAITH); 1608 break; 1609 } 1610 error = sooptcopyout(sopt, &optval, sizeof optval); 1611 break; 1612 1613 case IP_MULTICAST_IF: 1614 case IP_MULTICAST_VIF: 1615 case IP_MULTICAST_TTL: 1616 case IP_MULTICAST_LOOP: 1617 case IP_ADD_MEMBERSHIP: 1618 case IP_DROP_MEMBERSHIP: 1619 error = ip_getmoptions(sopt, inp->inp_moptions); 1620 break; 1621 1622 #if defined(IPSEC) || defined(FAST_IPSEC) 1623 case IP_IPSEC_POLICY: 1624 { 1625 struct mbuf *m = NULL; 1626 caddr_t req = NULL; 1627 size_t len = 0; 1628 1629 if (m != 0) { 1630 req = mtod(m, caddr_t); 1631 len = m->m_len; 1632 } 1633 error = ipsec4_get_policy(sotoinpcb(so), req, len, &m); 1634 if (error == 0) 1635 error = soopt_mcopyout(sopt, m); /* XXX */ 1636 if (error == 0) 1637 m_freem(m); 1638 break; 1639 } 1640 #endif /*IPSEC*/ 1641 1642 default: 1643 error = ENOPROTOOPT; 1644 break; 1645 } 1646 break; 1647 } 1648 return (error); 1649 } 1650 1651 /* 1652 * Set up IP options in pcb for insertion in output packets. 1653 * Store in mbuf with pointer in pcbopt, adding pseudo-option 1654 * with destination address if source routed. 1655 */ 1656 static int 1657 ip_pcbopts(optname, pcbopt, m) 1658 int optname; 1659 struct mbuf **pcbopt; 1660 register struct mbuf *m; 1661 { 1662 register int cnt, optlen; 1663 register u_char *cp; 1664 u_char opt; 1665 1666 /* turn off any old options */ 1667 if (*pcbopt) 1668 (void)m_free(*pcbopt); 1669 *pcbopt = 0; 1670 if (m == (struct mbuf *)0 || m->m_len == 0) { 1671 /* 1672 * Only turning off any previous options. 1673 */ 1674 if (m) 1675 (void)m_free(m); 1676 return (0); 1677 } 1678 1679 if (m->m_len % sizeof(int32_t)) 1680 goto bad; 1681 /* 1682 * IP first-hop destination address will be stored before 1683 * actual options; move other options back 1684 * and clear it when none present. 1685 */ 1686 if (m->m_data + m->m_len + sizeof(struct in_addr) >= &m->m_dat[MLEN]) 1687 goto bad; 1688 cnt = m->m_len; 1689 m->m_len += sizeof(struct in_addr); 1690 cp = mtod(m, u_char *) + sizeof(struct in_addr); 1691 bcopy(mtod(m, void *), cp, (unsigned)cnt); 1692 bzero(mtod(m, void *), sizeof(struct in_addr)); 1693 1694 for (; cnt > 0; cnt -= optlen, cp += optlen) { 1695 opt = cp[IPOPT_OPTVAL]; 1696 if (opt == IPOPT_EOL) 1697 break; 1698 if (opt == IPOPT_NOP) 1699 optlen = 1; 1700 else { 1701 if (cnt < IPOPT_OLEN + sizeof(*cp)) 1702 goto bad; 1703 optlen = cp[IPOPT_OLEN]; 1704 if (optlen < IPOPT_OLEN + sizeof(*cp) || optlen > cnt) 1705 goto bad; 1706 } 1707 switch (opt) { 1708 1709 default: 1710 break; 1711 1712 case IPOPT_LSRR: 1713 case IPOPT_SSRR: 1714 /* 1715 * user process specifies route as: 1716 * ->A->B->C->D 1717 * D must be our final destination (but we can't 1718 * check that since we may not have connected yet). 1719 * A is first hop destination, which doesn't appear in 1720 * actual IP option, but is stored before the options. 1721 */ 1722 if (optlen < IPOPT_MINOFF - 1 + sizeof(struct in_addr)) 1723 goto bad; 1724 m->m_len -= sizeof(struct in_addr); 1725 cnt -= sizeof(struct in_addr); 1726 optlen -= sizeof(struct in_addr); 1727 cp[IPOPT_OLEN] = optlen; 1728 /* 1729 * Move first hop before start of options. 1730 */ 1731 bcopy((caddr_t)&cp[IPOPT_OFFSET+1], mtod(m, caddr_t), 1732 sizeof(struct in_addr)); 1733 /* 1734 * Then copy rest of options back 1735 * to close up the deleted entry. 1736 */ 1737 bcopy((&cp[IPOPT_OFFSET+1] + sizeof(struct in_addr)), 1738 &cp[IPOPT_OFFSET+1], 1739 (unsigned)cnt + sizeof(struct in_addr)); 1740 break; 1741 } 1742 } 1743 if (m->m_len > MAX_IPOPTLEN + sizeof(struct in_addr)) 1744 goto bad; 1745 *pcbopt = m; 1746 return (0); 1747 1748 bad: 1749 (void)m_free(m); 1750 return (EINVAL); 1751 } 1752 1753 /* 1754 * XXX 1755 * The whole multicast option thing needs to be re-thought. 1756 * Several of these options are equally applicable to non-multicast 1757 * transmission, and one (IP_MULTICAST_TTL) totally duplicates a 1758 * standard option (IP_TTL). 1759 */ 1760 1761 /* 1762 * following RFC1724 section 3.3, 0.0.0.0/8 is interpreted as interface index. 1763 */ 1764 static struct ifnet * 1765 ip_multicast_if(a, ifindexp) 1766 struct in_addr *a; 1767 int *ifindexp; 1768 { 1769 int ifindex; 1770 struct ifnet *ifp; 1771 1772 if (ifindexp) 1773 *ifindexp = 0; 1774 if (ntohl(a->s_addr) >> 24 == 0) { 1775 ifindex = ntohl(a->s_addr) & 0xffffff; 1776 if (ifindex < 0 || if_index < ifindex) 1777 return NULL; 1778 ifp = ifnet_byindex(ifindex); 1779 if (ifindexp) 1780 *ifindexp = ifindex; 1781 } else { 1782 INADDR_TO_IFP(*a, ifp); 1783 } 1784 return ifp; 1785 } 1786 1787 /* 1788 * Set the IP multicast options in response to user setsockopt(). 1789 */ 1790 static int 1791 ip_setmoptions(sopt, imop) 1792 struct sockopt *sopt; 1793 struct ip_moptions **imop; 1794 { 1795 int error = 0; 1796 int i; 1797 struct in_addr addr; 1798 struct ip_mreq mreq; 1799 struct ifnet *ifp; 1800 struct ip_moptions *imo = *imop; 1801 struct route ro; 1802 struct sockaddr_in *dst; 1803 int ifindex; 1804 int s; 1805 1806 if (imo == NULL) { 1807 /* 1808 * No multicast option buffer attached to the pcb; 1809 * allocate one and initialize to default values. 1810 */ 1811 imo = (struct ip_moptions*)malloc(sizeof(*imo), M_IPMOPTS, 1812 M_WAITOK); 1813 1814 if (imo == NULL) 1815 return (ENOBUFS); 1816 *imop = imo; 1817 imo->imo_multicast_ifp = NULL; 1818 imo->imo_multicast_addr.s_addr = INADDR_ANY; 1819 imo->imo_multicast_vif = -1; 1820 imo->imo_multicast_ttl = IP_DEFAULT_MULTICAST_TTL; 1821 imo->imo_multicast_loop = IP_DEFAULT_MULTICAST_LOOP; 1822 imo->imo_num_memberships = 0; 1823 } 1824 1825 switch (sopt->sopt_name) { 1826 /* store an index number for the vif you wanna use in the send */ 1827 case IP_MULTICAST_VIF: 1828 if (legal_vif_num == 0) { 1829 error = EOPNOTSUPP; 1830 break; 1831 } 1832 error = sooptcopyin(sopt, &i, sizeof i, sizeof i); 1833 if (error) 1834 break; 1835 if (!legal_vif_num(i) && (i != -1)) { 1836 error = EINVAL; 1837 break; 1838 } 1839 imo->imo_multicast_vif = i; 1840 break; 1841 1842 case IP_MULTICAST_IF: 1843 /* 1844 * Select the interface for outgoing multicast packets. 1845 */ 1846 error = sooptcopyin(sopt, &addr, sizeof addr, sizeof addr); 1847 if (error) 1848 break; 1849 /* 1850 * INADDR_ANY is used to remove a previous selection. 1851 * When no interface is selected, a default one is 1852 * chosen every time a multicast packet is sent. 1853 */ 1854 if (addr.s_addr == INADDR_ANY) { 1855 imo->imo_multicast_ifp = NULL; 1856 break; 1857 } 1858 /* 1859 * The selected interface is identified by its local 1860 * IP address. Find the interface and confirm that 1861 * it supports multicasting. 1862 */ 1863 s = splimp(); 1864 ifp = ip_multicast_if(&addr, &ifindex); 1865 if (ifp == NULL || (ifp->if_flags & IFF_MULTICAST) == 0) { 1866 splx(s); 1867 error = EADDRNOTAVAIL; 1868 break; 1869 } 1870 imo->imo_multicast_ifp = ifp; 1871 if (ifindex) 1872 imo->imo_multicast_addr = addr; 1873 else 1874 imo->imo_multicast_addr.s_addr = INADDR_ANY; 1875 splx(s); 1876 break; 1877 1878 case IP_MULTICAST_TTL: 1879 /* 1880 * Set the IP time-to-live for outgoing multicast packets. 1881 * The original multicast API required a char argument, 1882 * which is inconsistent with the rest of the socket API. 1883 * We allow either a char or an int. 1884 */ 1885 if (sopt->sopt_valsize == 1) { 1886 u_char ttl; 1887 error = sooptcopyin(sopt, &ttl, 1, 1); 1888 if (error) 1889 break; 1890 imo->imo_multicast_ttl = ttl; 1891 } else { 1892 u_int ttl; 1893 error = sooptcopyin(sopt, &ttl, sizeof ttl, 1894 sizeof ttl); 1895 if (error) 1896 break; 1897 if (ttl > 255) 1898 error = EINVAL; 1899 else 1900 imo->imo_multicast_ttl = ttl; 1901 } 1902 break; 1903 1904 case IP_MULTICAST_LOOP: 1905 /* 1906 * Set the loopback flag for outgoing multicast packets. 1907 * Must be zero or one. The original multicast API required a 1908 * char argument, which is inconsistent with the rest 1909 * of the socket API. We allow either a char or an int. 1910 */ 1911 if (sopt->sopt_valsize == 1) { 1912 u_char loop; 1913 error = sooptcopyin(sopt, &loop, 1, 1); 1914 if (error) 1915 break; 1916 imo->imo_multicast_loop = !!loop; 1917 } else { 1918 u_int loop; 1919 error = sooptcopyin(sopt, &loop, sizeof loop, 1920 sizeof loop); 1921 if (error) 1922 break; 1923 imo->imo_multicast_loop = !!loop; 1924 } 1925 break; 1926 1927 case IP_ADD_MEMBERSHIP: 1928 /* 1929 * Add a multicast group membership. 1930 * Group must be a valid IP multicast address. 1931 */ 1932 error = sooptcopyin(sopt, &mreq, sizeof mreq, sizeof mreq); 1933 if (error) 1934 break; 1935 1936 if (!IN_MULTICAST(ntohl(mreq.imr_multiaddr.s_addr))) { 1937 error = EINVAL; 1938 break; 1939 } 1940 s = splimp(); 1941 /* 1942 * If no interface address was provided, use the interface of 1943 * the route to the given multicast address. 1944 */ 1945 if (mreq.imr_interface.s_addr == INADDR_ANY) { 1946 bzero((caddr_t)&ro, sizeof(ro)); 1947 dst = (struct sockaddr_in *)&ro.ro_dst; 1948 dst->sin_len = sizeof(*dst); 1949 dst->sin_family = AF_INET; 1950 dst->sin_addr = mreq.imr_multiaddr; 1951 rtalloc(&ro); 1952 if (ro.ro_rt == NULL) { 1953 error = EADDRNOTAVAIL; 1954 splx(s); 1955 break; 1956 } 1957 ifp = ro.ro_rt->rt_ifp; 1958 rtfree(ro.ro_rt); 1959 } 1960 else { 1961 ifp = ip_multicast_if(&mreq.imr_interface, NULL); 1962 } 1963 1964 /* 1965 * See if we found an interface, and confirm that it 1966 * supports multicast. 1967 */ 1968 if (ifp == NULL || (ifp->if_flags & IFF_MULTICAST) == 0) { 1969 error = EADDRNOTAVAIL; 1970 splx(s); 1971 break; 1972 } 1973 /* 1974 * See if the membership already exists or if all the 1975 * membership slots are full. 1976 */ 1977 for (i = 0; i < imo->imo_num_memberships; ++i) { 1978 if (imo->imo_membership[i]->inm_ifp == ifp && 1979 imo->imo_membership[i]->inm_addr.s_addr 1980 == mreq.imr_multiaddr.s_addr) 1981 break; 1982 } 1983 if (i < imo->imo_num_memberships) { 1984 error = EADDRINUSE; 1985 splx(s); 1986 break; 1987 } 1988 if (i == IP_MAX_MEMBERSHIPS) { 1989 error = ETOOMANYREFS; 1990 splx(s); 1991 break; 1992 } 1993 /* 1994 * Everything looks good; add a new record to the multicast 1995 * address list for the given interface. 1996 */ 1997 if ((imo->imo_membership[i] = 1998 in_addmulti(&mreq.imr_multiaddr, ifp)) == NULL) { 1999 error = ENOBUFS; 2000 splx(s); 2001 break; 2002 } 2003 ++imo->imo_num_memberships; 2004 splx(s); 2005 break; 2006 2007 case IP_DROP_MEMBERSHIP: 2008 /* 2009 * Drop a multicast group membership. 2010 * Group must be a valid IP multicast address. 2011 */ 2012 error = sooptcopyin(sopt, &mreq, sizeof mreq, sizeof mreq); 2013 if (error) 2014 break; 2015 2016 if (!IN_MULTICAST(ntohl(mreq.imr_multiaddr.s_addr))) { 2017 error = EINVAL; 2018 break; 2019 } 2020 2021 s = splimp(); 2022 /* 2023 * If an interface address was specified, get a pointer 2024 * to its ifnet structure. 2025 */ 2026 if (mreq.imr_interface.s_addr == INADDR_ANY) 2027 ifp = NULL; 2028 else { 2029 ifp = ip_multicast_if(&mreq.imr_interface, NULL); 2030 if (ifp == NULL) { 2031 error = EADDRNOTAVAIL; 2032 splx(s); 2033 break; 2034 } 2035 } 2036 /* 2037 * Find the membership in the membership array. 2038 */ 2039 for (i = 0; i < imo->imo_num_memberships; ++i) { 2040 if ((ifp == NULL || 2041 imo->imo_membership[i]->inm_ifp == ifp) && 2042 imo->imo_membership[i]->inm_addr.s_addr == 2043 mreq.imr_multiaddr.s_addr) 2044 break; 2045 } 2046 if (i == imo->imo_num_memberships) { 2047 error = EADDRNOTAVAIL; 2048 splx(s); 2049 break; 2050 } 2051 /* 2052 * Give up the multicast address record to which the 2053 * membership points. 2054 */ 2055 in_delmulti(imo->imo_membership[i]); 2056 /* 2057 * Remove the gap in the membership array. 2058 */ 2059 for (++i; i < imo->imo_num_memberships; ++i) 2060 imo->imo_membership[i-1] = imo->imo_membership[i]; 2061 --imo->imo_num_memberships; 2062 splx(s); 2063 break; 2064 2065 default: 2066 error = EOPNOTSUPP; 2067 break; 2068 } 2069 2070 /* 2071 * If all options have default values, no need to keep the mbuf. 2072 */ 2073 if (imo->imo_multicast_ifp == NULL && 2074 imo->imo_multicast_vif == -1 && 2075 imo->imo_multicast_ttl == IP_DEFAULT_MULTICAST_TTL && 2076 imo->imo_multicast_loop == IP_DEFAULT_MULTICAST_LOOP && 2077 imo->imo_num_memberships == 0) { 2078 free(*imop, M_IPMOPTS); 2079 *imop = NULL; 2080 } 2081 2082 return (error); 2083 } 2084 2085 /* 2086 * Return the IP multicast options in response to user getsockopt(). 2087 */ 2088 static int 2089 ip_getmoptions(sopt, imo) 2090 struct sockopt *sopt; 2091 register struct ip_moptions *imo; 2092 { 2093 struct in_addr addr; 2094 struct in_ifaddr *ia; 2095 int error, optval; 2096 u_char coptval; 2097 2098 error = 0; 2099 switch (sopt->sopt_name) { 2100 case IP_MULTICAST_VIF: 2101 if (imo != NULL) 2102 optval = imo->imo_multicast_vif; 2103 else 2104 optval = -1; 2105 error = sooptcopyout(sopt, &optval, sizeof optval); 2106 break; 2107 2108 case IP_MULTICAST_IF: 2109 if (imo == NULL || imo->imo_multicast_ifp == NULL) 2110 addr.s_addr = INADDR_ANY; 2111 else if (imo->imo_multicast_addr.s_addr) { 2112 /* return the value user has set */ 2113 addr = imo->imo_multicast_addr; 2114 } else { 2115 IFP_TO_IA(imo->imo_multicast_ifp, ia); 2116 addr.s_addr = (ia == NULL) ? INADDR_ANY 2117 : IA_SIN(ia)->sin_addr.s_addr; 2118 } 2119 error = sooptcopyout(sopt, &addr, sizeof addr); 2120 break; 2121 2122 case IP_MULTICAST_TTL: 2123 if (imo == 0) 2124 optval = coptval = IP_DEFAULT_MULTICAST_TTL; 2125 else 2126 optval = coptval = imo->imo_multicast_ttl; 2127 if (sopt->sopt_valsize == 1) 2128 error = sooptcopyout(sopt, &coptval, 1); 2129 else 2130 error = sooptcopyout(sopt, &optval, sizeof optval); 2131 break; 2132 2133 case IP_MULTICAST_LOOP: 2134 if (imo == 0) 2135 optval = coptval = IP_DEFAULT_MULTICAST_LOOP; 2136 else 2137 optval = coptval = imo->imo_multicast_loop; 2138 if (sopt->sopt_valsize == 1) 2139 error = sooptcopyout(sopt, &coptval, 1); 2140 else 2141 error = sooptcopyout(sopt, &optval, sizeof optval); 2142 break; 2143 2144 default: 2145 error = ENOPROTOOPT; 2146 break; 2147 } 2148 return (error); 2149 } 2150 2151 /* 2152 * Discard the IP multicast options. 2153 */ 2154 void 2155 ip_freemoptions(imo) 2156 register struct ip_moptions *imo; 2157 { 2158 register int i; 2159 2160 if (imo != NULL) { 2161 for (i = 0; i < imo->imo_num_memberships; ++i) 2162 in_delmulti(imo->imo_membership[i]); 2163 free(imo, M_IPMOPTS); 2164 } 2165 } 2166 2167 /* 2168 * Routine called from ip_output() to loop back a copy of an IP multicast 2169 * packet to the input queue of a specified interface. Note that this 2170 * calls the output routine of the loopback "driver", but with an interface 2171 * pointer that might NOT be a loopback interface -- evil, but easier than 2172 * replicating that code here. 2173 */ 2174 static void 2175 ip_mloopback(ifp, m, dst, hlen) 2176 struct ifnet *ifp; 2177 register struct mbuf *m; 2178 register struct sockaddr_in *dst; 2179 int hlen; 2180 { 2181 register struct ip *ip; 2182 struct mbuf *copym; 2183 2184 copym = m_copy(m, 0, M_COPYALL); 2185 if (copym != NULL && (copym->m_flags & M_EXT || copym->m_len < hlen)) 2186 copym = m_pullup(copym, hlen); 2187 if (copym != NULL) { 2188 /* 2189 * We don't bother to fragment if the IP length is greater 2190 * than the interface's MTU. Can this possibly matter? 2191 */ 2192 ip = mtod(copym, struct ip *); 2193 ip->ip_len = htons(ip->ip_len); 2194 ip->ip_off = htons(ip->ip_off); 2195 ip->ip_sum = 0; 2196 ip->ip_sum = in_cksum(copym, hlen); 2197 /* 2198 * NB: 2199 * It's not clear whether there are any lingering 2200 * reentrancy problems in other areas which might 2201 * be exposed by using ip_input directly (in 2202 * particular, everything which modifies the packet 2203 * in-place). Yet another option is using the 2204 * protosw directly to deliver the looped back 2205 * packet. For the moment, we'll err on the side 2206 * of safety by using if_simloop(). 2207 */ 2208 #if 1 /* XXX */ 2209 if (dst->sin_family != AF_INET) { 2210 printf("ip_mloopback: bad address family %d\n", 2211 dst->sin_family); 2212 dst->sin_family = AF_INET; 2213 } 2214 #endif 2215 2216 #ifdef notdef 2217 copym->m_pkthdr.rcvif = ifp; 2218 ip_input(copym); 2219 #else 2220 /* if the checksum hasn't been computed, mark it as valid */ 2221 if (copym->m_pkthdr.csum_flags & CSUM_DELAY_DATA) { 2222 copym->m_pkthdr.csum_flags |= 2223 CSUM_DATA_VALID | CSUM_PSEUDO_HDR; 2224 copym->m_pkthdr.csum_data = 0xffff; 2225 } 2226 if_simloop(ifp, copym, dst->sin_family, 0); 2227 #endif 2228 } 2229 }
Cache object: ab5e06441722fd5f14ba34da823dda63
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