Now available: The Design and Implementation of the FreeBSD Operating System (Second Edition)
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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 * $FreeBSD$ 35 */ 36 37 #define _IP_VHL 38 39 #include "opt_ipfw.h" 40 #include "opt_ipdn.h" 41 #include "opt_ipdivert.h" 42 #include "opt_ipfilter.h" 43 #include "opt_ipsec.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/malloc.h> 51 #include <sys/mbuf.h> 52 #include <sys/protosw.h> 53 #include <sys/socket.h> 54 #include <sys/socketvar.h> 55 #include <sys/proc.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 extern int (*fr_checkp) (struct ip *, int, struct ifnet *, int, struct mbuf **); 117 118 119 extern struct protosw inetsw[]; 120 121 /* 122 * IP output. The packet in mbuf chain m contains a skeletal IP 123 * header (with len, off, ttl, proto, tos, src, dst). 124 * The mbuf chain containing the packet will be freed. 125 * The mbuf opt, if present, will not be freed. 126 */ 127 int 128 ip_output(struct mbuf *m0, struct mbuf *opt, struct route *ro, 129 int flags, struct ip_moptions *imo, struct inpcb *inp) 130 { 131 struct ip *ip; 132 struct ifnet *ifp = NULL; /* keep compiler happy */ 133 struct mbuf *m; 134 int hlen = sizeof (struct ip); 135 int len, off, error = 0; 136 struct sockaddr_in *dst = NULL; /* keep compiler happy */ 137 struct in_ifaddr *ia = NULL; 138 int isbroadcast, sw_csum; 139 struct in_addr pkt_dst; 140 #ifdef IPSEC 141 struct route iproute; 142 struct secpolicy *sp = NULL; 143 struct socket *so = inp ? inp->inp_socket : NULL; 144 #endif 145 #ifdef FAST_IPSEC 146 struct route iproute; 147 struct m_tag *mtag; 148 struct secpolicy *sp = NULL; 149 struct tdb_ident *tdbi; 150 int s; 151 #endif /* FAST_IPSEC */ 152 struct ip_fw_args args; 153 int src_was_INADDR_ANY = 0; /* as the name says... */ 154 155 args.eh = NULL; 156 args.rule = NULL; 157 args.next_hop = NULL; 158 args.divert_rule = 0; /* divert cookie */ 159 160 /* Grab info from MT_TAG mbufs prepended to the chain. */ 161 for (; m0 && m0->m_type == MT_TAG; m0 = m0->m_next) { 162 switch(m0->_m_tag_id) { 163 default: 164 printf("ip_output: unrecognised MT_TAG tag %d\n", 165 m0->_m_tag_id); 166 break; 167 168 case PACKET_TAG_DUMMYNET: 169 /* 170 * the packet was already tagged, so part of the 171 * processing was already done, and we need to go down. 172 * Get parameters from the header. 173 */ 174 args.rule = ((struct dn_pkt *)m0)->rule; 175 opt = NULL ; 176 ro = & ( ((struct dn_pkt *)m0)->ro ) ; 177 imo = NULL ; 178 dst = ((struct dn_pkt *)m0)->dn_dst ; 179 ifp = ((struct dn_pkt *)m0)->ifp ; 180 flags = ((struct dn_pkt *)m0)->flags ; 181 break; 182 183 case PACKET_TAG_DIVERT: 184 args.divert_rule = (int)m0->m_data & 0xffff; 185 break; 186 187 case PACKET_TAG_IPFORWARD: 188 args.next_hop = (struct sockaddr_in *)m0->m_data; 189 break; 190 } 191 } 192 m = m0; 193 194 KASSERT(!m || (m->m_flags & M_PKTHDR) != 0, ("ip_output: no HDR")); 195 #ifndef FAST_IPSEC 196 KASSERT(ro != NULL, ("ip_output: no route, proto %d", 197 mtod(m, struct ip *)->ip_p)); 198 #endif 199 200 if (args.rule != NULL) { /* dummynet already saw us */ 201 ip = mtod(m, struct ip *); 202 hlen = IP_VHL_HL(ip->ip_vhl) << 2 ; 203 if (ro->ro_rt) 204 ia = ifatoia(ro->ro_rt->rt_ifa); 205 goto sendit; 206 } 207 208 if (opt) { 209 len = 0; 210 m = ip_insertoptions(m, opt, &len); 211 if (len != 0) 212 hlen = len; 213 } 214 ip = mtod(m, struct ip *); 215 pkt_dst = args.next_hop ? args.next_hop->sin_addr : ip->ip_dst; 216 217 /* 218 * Fill in IP header. 219 */ 220 if ((flags & (IP_FORWARDING|IP_RAWOUTPUT)) == 0) { 221 ip->ip_vhl = IP_MAKE_VHL(IPVERSION, hlen >> 2); 222 ip->ip_off &= IP_DF; 223 #ifdef RANDOM_IP_ID 224 ip->ip_id = ip_randomid(); 225 #else 226 ip->ip_id = htons(ip_id++); 227 #endif 228 ipstat.ips_localout++; 229 } else { 230 hlen = IP_VHL_HL(ip->ip_vhl) << 2; 231 } 232 233 #ifdef FAST_IPSEC 234 if (ro == NULL) { 235 ro = &iproute; 236 bzero(ro, sizeof (*ro)); 237 } 238 #endif /* FAST_IPSEC */ 239 dst = (struct sockaddr_in *)&ro->ro_dst; 240 /* 241 * If there is a cached route, 242 * check that it is to the same destination 243 * and is still up. If not, free it and try again. 244 * The address family should also be checked in case of sharing the 245 * cache with IPv6. 246 */ 247 if (ro->ro_rt && ((ro->ro_rt->rt_flags & RTF_UP) == 0 || 248 dst->sin_family != AF_INET || 249 dst->sin_addr.s_addr != pkt_dst.s_addr)) { 250 RTFREE(ro->ro_rt); 251 ro->ro_rt = (struct rtentry *)0; 252 } 253 if (ro->ro_rt == 0) { 254 bzero(dst, sizeof(*dst)); 255 dst->sin_family = AF_INET; 256 dst->sin_len = sizeof(*dst); 257 dst->sin_addr = pkt_dst; 258 } 259 /* 260 * If routing to interface only, 261 * short circuit routing lookup. 262 */ 263 if (flags & IP_ROUTETOIF) { 264 if ((ia = ifatoia(ifa_ifwithdstaddr(sintosa(dst)))) == 0 && 265 (ia = ifatoia(ifa_ifwithnet(sintosa(dst)))) == 0) { 266 ipstat.ips_noroute++; 267 error = ENETUNREACH; 268 goto bad; 269 } 270 ifp = ia->ia_ifp; 271 ip->ip_ttl = 1; 272 isbroadcast = in_broadcast(dst->sin_addr, ifp); 273 } else if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) && 274 imo != NULL && imo->imo_multicast_ifp != NULL) { 275 /* 276 * Bypass the normal routing lookup for multicast 277 * packets if the interface is specified. 278 */ 279 ifp = imo->imo_multicast_ifp; 280 IFP_TO_IA(ifp, ia); 281 isbroadcast = 0; /* fool gcc */ 282 } else { 283 /* 284 * If this is the case, we probably don't want to allocate 285 * a protocol-cloned route since we didn't get one from the 286 * ULP. This lets TCP do its thing, while not burdening 287 * forwarding or ICMP with the overhead of cloning a route. 288 * Of course, we still want to do any cloning requested by 289 * the link layer, as this is probably required in all cases 290 * for correct operation (as it is for ARP). 291 */ 292 if (ro->ro_rt == 0) 293 rtalloc_ign(ro, RTF_PRCLONING); 294 if (ro->ro_rt == 0) { 295 ipstat.ips_noroute++; 296 error = EHOSTUNREACH; 297 goto bad; 298 } 299 ia = ifatoia(ro->ro_rt->rt_ifa); 300 ifp = ro->ro_rt->rt_ifp; 301 ro->ro_rt->rt_use++; 302 if (ro->ro_rt->rt_flags & RTF_GATEWAY) 303 dst = (struct sockaddr_in *)ro->ro_rt->rt_gateway; 304 if (ro->ro_rt->rt_flags & RTF_HOST) 305 isbroadcast = (ro->ro_rt->rt_flags & RTF_BROADCAST); 306 else 307 isbroadcast = in_broadcast(dst->sin_addr, ifp); 308 } 309 if (IN_MULTICAST(ntohl(pkt_dst.s_addr))) { 310 struct in_multi *inm; 311 312 m->m_flags |= M_MCAST; 313 /* 314 * IP destination address is multicast. Make sure "dst" 315 * still points to the address in "ro". (It may have been 316 * changed to point to a gateway address, above.) 317 */ 318 dst = (struct sockaddr_in *)&ro->ro_dst; 319 /* 320 * See if the caller provided any multicast options 321 */ 322 if (imo != NULL) { 323 ip->ip_ttl = imo->imo_multicast_ttl; 324 if (imo->imo_multicast_vif != -1) 325 ip->ip_src.s_addr = 326 ip_mcast_src ? 327 ip_mcast_src(imo->imo_multicast_vif) : 328 INADDR_ANY; 329 } else 330 ip->ip_ttl = IP_DEFAULT_MULTICAST_TTL; 331 /* 332 * Confirm that the outgoing interface supports multicast. 333 */ 334 if ((imo == NULL) || (imo->imo_multicast_vif == -1)) { 335 if ((ifp->if_flags & IFF_MULTICAST) == 0) { 336 ipstat.ips_noroute++; 337 error = ENETUNREACH; 338 goto bad; 339 } 340 } 341 /* 342 * If source address not specified yet, use address 343 * of outgoing interface. 344 */ 345 if (ip->ip_src.s_addr == INADDR_ANY) { 346 /* Interface may have no addresses. */ 347 if (ia != NULL) 348 ip->ip_src = IA_SIN(ia)->sin_addr; 349 } 350 351 IN_LOOKUP_MULTI(pkt_dst, ifp, inm); 352 if (inm != NULL && 353 (imo == NULL || imo->imo_multicast_loop)) { 354 /* 355 * If we belong to the destination multicast group 356 * on the outgoing interface, and the caller did not 357 * forbid loopback, loop back a copy. 358 */ 359 ip_mloopback(ifp, m, dst, hlen); 360 } 361 else { 362 /* 363 * If we are acting as a multicast router, perform 364 * multicast forwarding as if the packet had just 365 * arrived on the interface to which we are about 366 * to send. The multicast forwarding function 367 * recursively calls this function, using the 368 * IP_FORWARDING flag to prevent infinite recursion. 369 * 370 * Multicasts that are looped back by ip_mloopback(), 371 * above, will be forwarded by the ip_input() routine, 372 * if necessary. 373 */ 374 if (ip_mrouter && (flags & IP_FORWARDING) == 0) { 375 /* 376 * If rsvp daemon is not running, do not 377 * set ip_moptions. This ensures that the packet 378 * is multicast and not just sent down one link 379 * as prescribed by rsvpd. 380 */ 381 if (!rsvp_on) 382 imo = NULL; 383 if (ip_mforward && 384 ip_mforward(ip, ifp, m, imo) != 0) { 385 m_freem(m); 386 goto done; 387 } 388 } 389 } 390 391 /* 392 * Multicasts with a time-to-live of zero may be looped- 393 * back, above, but must not be transmitted on a network. 394 * Also, multicasts addressed to the loopback interface 395 * are not sent -- the above call to ip_mloopback() will 396 * loop back a copy if this host actually belongs to the 397 * destination group on the loopback interface. 398 */ 399 if (ip->ip_ttl == 0 || ifp->if_flags & IFF_LOOPBACK) { 400 m_freem(m); 401 goto done; 402 } 403 404 goto sendit; 405 } 406 #ifndef notdef 407 /* 408 * If the source address is not specified yet, use the address 409 * of the outoing interface. In case, keep note we did that, so 410 * if the the firewall changes the next-hop causing the output 411 * interface to change, we can fix that. 412 */ 413 if (ip->ip_src.s_addr == INADDR_ANY) { 414 /* Interface may have no addresses. */ 415 if (ia != NULL) { 416 ip->ip_src = IA_SIN(ia)->sin_addr; 417 src_was_INADDR_ANY = 1; 418 } 419 } 420 #endif /* notdef */ 421 /* 422 * Verify that we have any chance at all of being able to queue 423 * the packet or packet fragments 424 */ 425 if ((ifp->if_snd.ifq_len + ip->ip_len / ifp->if_mtu + 1) >= 426 ifp->if_snd.ifq_maxlen) { 427 error = ENOBUFS; 428 ipstat.ips_odropped++; 429 goto bad; 430 } 431 432 /* 433 * Look for broadcast address and 434 * verify user is allowed to send 435 * such a packet. 436 */ 437 if (isbroadcast) { 438 if ((ifp->if_flags & IFF_BROADCAST) == 0) { 439 error = EADDRNOTAVAIL; 440 goto bad; 441 } 442 if ((flags & IP_ALLOWBROADCAST) == 0) { 443 error = EACCES; 444 goto bad; 445 } 446 /* don't allow broadcast messages to be fragmented */ 447 if (ip->ip_len > ifp->if_mtu) { 448 error = EMSGSIZE; 449 goto bad; 450 } 451 if (flags & IP_SENDONES) 452 ip->ip_dst.s_addr = INADDR_BROADCAST; 453 m->m_flags |= M_BCAST; 454 } else { 455 m->m_flags &= ~M_BCAST; 456 } 457 458 sendit: 459 #ifdef IPSEC 460 /* get SP for this packet */ 461 if (so == NULL) 462 sp = ipsec4_getpolicybyaddr(m, IPSEC_DIR_OUTBOUND, flags, &error); 463 else 464 sp = ipsec4_getpolicybysock(m, IPSEC_DIR_OUTBOUND, so, &error); 465 466 if (sp == NULL) { 467 ipsecstat.out_inval++; 468 goto bad; 469 } 470 471 error = 0; 472 473 /* check policy */ 474 switch (sp->policy) { 475 case IPSEC_POLICY_DISCARD: 476 /* 477 * This packet is just discarded. 478 */ 479 ipsecstat.out_polvio++; 480 goto bad; 481 482 case IPSEC_POLICY_BYPASS: 483 case IPSEC_POLICY_NONE: 484 case IPSEC_POLICY_TCP: 485 /* no need to do IPsec. */ 486 goto skip_ipsec; 487 488 case IPSEC_POLICY_IPSEC: 489 if (sp->req == NULL) { 490 /* acquire a policy */ 491 error = key_spdacquire(sp); 492 goto bad; 493 } 494 break; 495 496 case IPSEC_POLICY_ENTRUST: 497 default: 498 printf("ip_output: Invalid policy found. %d\n", sp->policy); 499 } 500 { 501 struct ipsec_output_state state; 502 bzero(&state, sizeof(state)); 503 state.m = m; 504 if (flags & IP_ROUTETOIF) { 505 state.ro = &iproute; 506 bzero(&iproute, sizeof(iproute)); 507 } else 508 state.ro = ro; 509 state.dst = (struct sockaddr *)dst; 510 511 ip->ip_sum = 0; 512 513 /* 514 * XXX 515 * delayed checksums are not currently compatible with IPsec 516 */ 517 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) { 518 in_delayed_cksum(m); 519 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA; 520 } 521 522 ip->ip_len = htons(ip->ip_len); 523 ip->ip_off = htons(ip->ip_off); 524 525 error = ipsec4_output(&state, sp, flags); 526 527 m = state.m; 528 if (flags & IP_ROUTETOIF) { 529 /* 530 * if we have tunnel mode SA, we may need to ignore 531 * IP_ROUTETOIF. 532 */ 533 if (state.ro != &iproute || state.ro->ro_rt != NULL) { 534 flags &= ~IP_ROUTETOIF; 535 ro = state.ro; 536 } 537 } else 538 ro = state.ro; 539 dst = (struct sockaddr_in *)state.dst; 540 if (error) { 541 /* mbuf is already reclaimed in ipsec4_output. */ 542 m0 = NULL; 543 switch (error) { 544 case EHOSTUNREACH: 545 case ENETUNREACH: 546 case EMSGSIZE: 547 case ENOBUFS: 548 case ENOMEM: 549 break; 550 default: 551 printf("ip4_output (ipsec): error code %d\n", error); 552 /*fall through*/ 553 case ENOENT: 554 /* don't show these error codes to the user */ 555 error = 0; 556 break; 557 } 558 goto bad; 559 } 560 } 561 562 /* be sure to update variables that are affected by ipsec4_output() */ 563 ip = mtod(m, struct ip *); 564 #ifdef _IP_VHL 565 hlen = IP_VHL_HL(ip->ip_vhl) << 2; 566 #else 567 hlen = ip->ip_hl << 2; 568 #endif 569 if (ro->ro_rt == NULL) { 570 if ((flags & IP_ROUTETOIF) == 0) { 571 printf("ip_output: " 572 "can't update route after IPsec processing\n"); 573 error = EHOSTUNREACH; /*XXX*/ 574 goto bad; 575 } 576 } else { 577 ia = ifatoia(ro->ro_rt->rt_ifa); 578 ifp = ro->ro_rt->rt_ifp; 579 } 580 581 /* make it flipped, again. */ 582 ip->ip_len = ntohs(ip->ip_len); 583 ip->ip_off = ntohs(ip->ip_off); 584 skip_ipsec: 585 #endif /*IPSEC*/ 586 #ifdef FAST_IPSEC 587 /* 588 * Check the security policy (SP) for the packet and, if 589 * required, do IPsec-related processing. There are two 590 * cases here; the first time a packet is sent through 591 * it will be untagged and handled by ipsec4_checkpolicy. 592 * If the packet is resubmitted to ip_output (e.g. after 593 * AH, ESP, etc. processing), there will be a tag to bypass 594 * the lookup and related policy checking. 595 */ 596 mtag = m_tag_find(m, PACKET_TAG_IPSEC_PENDING_TDB, NULL); 597 s = splnet(); 598 if (mtag != NULL) { 599 tdbi = (struct tdb_ident *)(mtag + 1); 600 sp = ipsec_getpolicy(tdbi, IPSEC_DIR_OUTBOUND); 601 if (sp == NULL) 602 error = -EINVAL; /* force silent drop */ 603 m_tag_delete(m, mtag); 604 } else { 605 sp = ipsec4_checkpolicy(m, IPSEC_DIR_OUTBOUND, flags, 606 &error, inp); 607 } 608 /* 609 * There are four return cases: 610 * sp != NULL apply IPsec policy 611 * sp == NULL, error == 0 no IPsec handling needed 612 * sp == NULL, error == -EINVAL discard packet w/o error 613 * sp == NULL, error != 0 discard packet, report error 614 */ 615 if (sp != NULL) { 616 /* Loop detection, check if ipsec processing already done */ 617 KASSERT(sp->req != NULL, ("ip_output: no ipsec request")); 618 for (mtag = m_tag_first(m); mtag != NULL; 619 mtag = m_tag_next(m, mtag)) { 620 if (mtag->m_tag_cookie != MTAG_ABI_COMPAT) 621 continue; 622 if (mtag->m_tag_id != PACKET_TAG_IPSEC_OUT_DONE && 623 mtag->m_tag_id != PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED) 624 continue; 625 /* 626 * Check if policy has an SA associated with it. 627 * This can happen when an SP has yet to acquire 628 * an SA; e.g. on first reference. If it occurs, 629 * then we let ipsec4_process_packet do its thing. 630 */ 631 if (sp->req->sav == NULL) 632 break; 633 tdbi = (struct tdb_ident *)(mtag + 1); 634 if (tdbi->spi == sp->req->sav->spi && 635 tdbi->proto == sp->req->sav->sah->saidx.proto && 636 bcmp(&tdbi->dst, &sp->req->sav->sah->saidx.dst, 637 sizeof (union sockaddr_union)) == 0) { 638 /* 639 * No IPsec processing is needed, free 640 * reference to SP. 641 * 642 * NB: null pointer to avoid free at 643 * done: below. 644 */ 645 KEY_FREESP(&sp), sp = NULL; 646 splx(s); 647 goto spd_done; 648 } 649 } 650 651 /* 652 * Do delayed checksums now because we send before 653 * this is done in the normal processing path. 654 */ 655 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) { 656 in_delayed_cksum(m); 657 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA; 658 } 659 660 ip->ip_len = htons(ip->ip_len); 661 ip->ip_off = htons(ip->ip_off); 662 663 /* NB: callee frees mbuf */ 664 error = ipsec4_process_packet(m, sp->req, flags, 0); 665 /* 666 * Preserve KAME behaviour: ENOENT can be returned 667 * when an SA acquire is in progress. Don't propagate 668 * this to user-level; it confuses applications. 669 * 670 * XXX this will go away when the SADB is redone. 671 */ 672 if (error == ENOENT) 673 error = 0; 674 splx(s); 675 goto done; 676 } else { 677 splx(s); 678 679 if (error != 0) { 680 /* 681 * Hack: -EINVAL is used to signal that a packet 682 * should be silently discarded. This is typically 683 * because we asked key management for an SA and 684 * it was delayed (e.g. kicked up to IKE). 685 */ 686 if (error == -EINVAL) 687 error = 0; 688 goto bad; 689 } else { 690 /* No IPsec processing for this packet. */ 691 } 692 #ifdef notyet 693 /* 694 * If deferred crypto processing is needed, check that 695 * the interface supports it. 696 */ 697 mtag = m_tag_find(m, PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED, NULL); 698 if (mtag != NULL && (ifp->if_capenable & IFCAP_IPSEC) == 0) { 699 /* notify IPsec to do its own crypto */ 700 ipsp_skipcrypto_unmark((struct tdb_ident *)(mtag + 1)); 701 error = EHOSTUNREACH; 702 goto bad; 703 } 704 #endif 705 } 706 spd_done: 707 #endif /* FAST_IPSEC */ 708 /* 709 * IpHack's section. 710 * - Xlate: translate packet's addr/port (NAT). 711 * - Firewall: deny/allow/etc. 712 * - Wrap: fake packet's addr/port <unimpl.> 713 * - Encapsulate: put it in another IP and send out. <unimp.> 714 */ 715 if (fr_checkp) { 716 struct mbuf *m1 = m; 717 718 if ((error = (*fr_checkp)(ip, hlen, ifp, 1, &m1)) || !m1) 719 goto done; 720 ip = mtod(m = m1, struct ip *); 721 } 722 723 /* 724 * Check with the firewall... 725 * but not if we are already being fwd'd from a firewall. 726 */ 727 if (fw_enable && IPFW_LOADED && !args.next_hop) { 728 struct sockaddr_in *old = dst; 729 730 args.m = m; 731 args.next_hop = dst; 732 args.oif = ifp; 733 off = ip_fw_chk_ptr(&args); 734 m = args.m; 735 dst = args.next_hop; 736 737 /* 738 * On return we must do the following: 739 * m == NULL -> drop the pkt (old interface, deprecated) 740 * (off & IP_FW_PORT_DENY_FLAG) -> drop the pkt (new interface) 741 * 1<=off<= 0xffff -> DIVERT 742 * (off & IP_FW_PORT_DYNT_FLAG) -> send to a DUMMYNET pipe 743 * (off & IP_FW_PORT_TEE_FLAG) -> TEE the packet 744 * dst != old -> IPFIREWALL_FORWARD 745 * off==0, dst==old -> accept 746 * If some of the above modules are not compiled in, then 747 * we should't have to check the corresponding condition 748 * (because the ipfw control socket should not accept 749 * unsupported rules), but better play safe and drop 750 * packets in case of doubt. 751 */ 752 if ( (off & IP_FW_PORT_DENY_FLAG) || m == NULL) { 753 if (m) 754 m_freem(m); 755 error = EACCES; 756 goto done; 757 } 758 ip = mtod(m, struct ip *); 759 if (off == 0 && dst == old) /* common case */ 760 goto pass; 761 if (DUMMYNET_LOADED && (off & IP_FW_PORT_DYNT_FLAG) != 0) { 762 /* 763 * pass the pkt to dummynet. Need to include 764 * pipe number, m, ifp, ro, dst because these are 765 * not recomputed in the next pass. 766 * All other parameters have been already used and 767 * so they are not needed anymore. 768 * XXX note: if the ifp or ro entry are deleted 769 * while a pkt is in dummynet, we are in trouble! 770 */ 771 args.ro = ro; 772 args.dst = dst; 773 args.flags = flags; 774 775 error = ip_dn_io_ptr(m, off & 0xffff, DN_TO_IP_OUT, 776 &args); 777 goto done; 778 } 779 #ifdef IPDIVERT 780 if (off != 0 && (off & IP_FW_PORT_DYNT_FLAG) == 0) { 781 struct mbuf *clone = NULL; 782 783 /* Clone packet if we're doing a 'tee' */ 784 if ((off & IP_FW_PORT_TEE_FLAG) != 0) 785 clone = m_dup(m, M_DONTWAIT); 786 787 /* 788 * XXX 789 * delayed checksums are not currently compatible 790 * with divert sockets. 791 */ 792 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) { 793 in_delayed_cksum(m); 794 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA; 795 } 796 797 /* Restore packet header fields to original values */ 798 ip->ip_len = htons(ip->ip_len); 799 ip->ip_off = htons(ip->ip_off); 800 801 /* Deliver packet to divert input routine */ 802 divert_packet(m, 0, off & 0xffff, args.divert_rule); 803 804 /* If 'tee', continue with original packet */ 805 if (clone != NULL) { 806 m = clone; 807 ip = mtod(m, struct ip *); 808 goto pass; 809 } 810 goto done; 811 } 812 #endif 813 814 /* IPFIREWALL_FORWARD */ 815 /* 816 * Check dst to make sure it is directly reachable on the 817 * interface we previously thought it was. 818 * If it isn't (which may be likely in some situations) we have 819 * to re-route it (ie, find a route for the next-hop and the 820 * associated interface) and set them here. This is nested 821 * forwarding which in most cases is undesirable, except where 822 * such control is nigh impossible. So we do it here. 823 * And I'm babbling. 824 */ 825 if (off == 0 && old != dst) { /* FORWARD, dst has changed */ 826 #if 0 827 /* 828 * XXX To improve readability, this block should be 829 * changed into a function call as below: 830 */ 831 error = ip_ipforward(&m, &dst, &ifp); 832 if (error) 833 goto bad; 834 if (m == NULL) /* ip_input consumed the mbuf */ 835 goto done; 836 #else 837 struct in_ifaddr *ia; 838 839 /* 840 * XXX sro_fwd below is static, and a pointer 841 * to it gets passed to routines downstream. 842 * This could have surprisingly bad results in 843 * practice, because its content is overwritten 844 * by subsequent packets. 845 */ 846 /* There must be a better way to do this next line... */ 847 static struct route sro_fwd; 848 struct route *ro_fwd = &sro_fwd; 849 850 #if 0 851 print_ip("IPFIREWALL_FORWARD: New dst ip: ", 852 dst->sin_addr, "\n"); 853 #endif 854 855 /* 856 * We need to figure out if we have been forwarded 857 * to a local socket. If so, then we should somehow 858 * "loop back" to ip_input, and get directed to the 859 * PCB as if we had received this packet. This is 860 * because it may be dificult to identify the packets 861 * you want to forward until they are being output 862 * and have selected an interface. (e.g. locally 863 * initiated packets) If we used the loopback inteface, 864 * we would not be able to control what happens 865 * as the packet runs through ip_input() as 866 * it is done through a ISR. 867 */ 868 LIST_FOREACH(ia, 869 INADDR_HASH(dst->sin_addr.s_addr), ia_hash) { 870 /* 871 * If the addr to forward to is one 872 * of ours, we pretend to 873 * be the destination for this packet. 874 */ 875 if (IA_SIN(ia)->sin_addr.s_addr == 876 dst->sin_addr.s_addr) 877 break; 878 } 879 if (ia) { /* tell ip_input "dont filter" */ 880 struct m_hdr tag; 881 882 tag.mh_type = MT_TAG; 883 tag.mh_flags = PACKET_TAG_IPFORWARD; 884 tag.mh_data = (caddr_t)args.next_hop; 885 tag.mh_next = m; 886 887 if (m->m_pkthdr.rcvif == NULL) 888 m->m_pkthdr.rcvif = ifunit("lo0"); 889 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) { 890 m->m_pkthdr.csum_flags |= 891 CSUM_DATA_VALID | CSUM_PSEUDO_HDR; 892 m->m_pkthdr.csum_data = 0xffff; 893 } 894 m->m_pkthdr.csum_flags |= 895 CSUM_IP_CHECKED | CSUM_IP_VALID; 896 ip->ip_len = htons(ip->ip_len); 897 ip->ip_off = htons(ip->ip_off); 898 ip_input((struct mbuf *)&tag); 899 goto done; 900 } 901 /* Some of the logic for this was 902 * nicked from above. 903 * 904 * This rewrites the cached route in a local PCB. 905 * Is this what we want to do? 906 */ 907 bcopy(dst, &ro_fwd->ro_dst, sizeof(*dst)); 908 909 ro_fwd->ro_rt = 0; 910 rtalloc_ign(ro_fwd, RTF_PRCLONING); 911 912 if (ro_fwd->ro_rt == 0) { 913 ipstat.ips_noroute++; 914 error = EHOSTUNREACH; 915 goto bad; 916 } 917 918 ia = ifatoia(ro_fwd->ro_rt->rt_ifa); 919 ifp = ro_fwd->ro_rt->rt_ifp; 920 ro_fwd->ro_rt->rt_use++; 921 if (ro_fwd->ro_rt->rt_flags & RTF_GATEWAY) 922 dst = (struct sockaddr_in *) 923 ro_fwd->ro_rt->rt_gateway; 924 if (ro_fwd->ro_rt->rt_flags & RTF_HOST) 925 isbroadcast = 926 (ro_fwd->ro_rt->rt_flags & RTF_BROADCAST); 927 else 928 isbroadcast = in_broadcast(dst->sin_addr, ifp); 929 if (ro->ro_rt) 930 RTFREE(ro->ro_rt); 931 ro->ro_rt = ro_fwd->ro_rt; 932 dst = (struct sockaddr_in *)&ro_fwd->ro_dst; 933 934 #endif /* ... block to be put into a function */ 935 /* 936 * If we added a default src ip earlier, 937 * which would have been gotten from the-then 938 * interface, do it again, from the new one. 939 */ 940 if (src_was_INADDR_ANY) 941 ip->ip_src = IA_SIN(ia)->sin_addr; 942 goto pass ; 943 } 944 945 /* 946 * if we get here, none of the above matches, and 947 * we have to drop the pkt 948 */ 949 m_freem(m); 950 error = EACCES; /* not sure this is the right error msg */ 951 goto done; 952 } 953 954 pass: 955 /* 127/8 must not appear on wire - RFC1122. */ 956 if ((ntohl(ip->ip_dst.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET || 957 (ntohl(ip->ip_src.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET) { 958 if ((ifp->if_flags & IFF_LOOPBACK) == 0) { 959 ipstat.ips_badaddr++; 960 error = EADDRNOTAVAIL; 961 goto bad; 962 } 963 } 964 965 m->m_pkthdr.csum_flags |= CSUM_IP; 966 sw_csum = m->m_pkthdr.csum_flags & ~ifp->if_hwassist; 967 if (sw_csum & CSUM_DELAY_DATA) { 968 in_delayed_cksum(m); 969 sw_csum &= ~CSUM_DELAY_DATA; 970 } 971 m->m_pkthdr.csum_flags &= ifp->if_hwassist; 972 973 /* 974 * If small enough for interface, or the interface will take 975 * care of the fragmentation for us, can just send directly. 976 */ 977 if (ip->ip_len <= ifp->if_mtu || ifp->if_hwassist & CSUM_FRAGMENT) { 978 ip->ip_len = htons(ip->ip_len); 979 ip->ip_off = htons(ip->ip_off); 980 ip->ip_sum = 0; 981 if (sw_csum & CSUM_DELAY_IP) { 982 if (ip->ip_vhl == IP_VHL_BORING) { 983 ip->ip_sum = in_cksum_hdr(ip); 984 } else { 985 ip->ip_sum = in_cksum(m, hlen); 986 } 987 } 988 989 /* Record statistics for this interface address. */ 990 if (!(flags & IP_FORWARDING) && ia) { 991 ia->ia_ifa.if_opackets++; 992 ia->ia_ifa.if_obytes += m->m_pkthdr.len; 993 } 994 995 #ifdef IPSEC 996 /* clean ipsec history once it goes out of the node */ 997 ipsec_delaux(m); 998 #endif 999 1000 #ifdef MBUF_STRESS_TEST 1001 if (mbuf_frag_size && m->m_pkthdr.len > mbuf_frag_size) 1002 m = m_fragment(m, M_DONTWAIT, mbuf_frag_size); 1003 #endif 1004 error = (*ifp->if_output)(ifp, m, 1005 (struct sockaddr *)dst, ro->ro_rt); 1006 goto done; 1007 } 1008 1009 if (ip->ip_off & IP_DF) { 1010 error = EMSGSIZE; 1011 /* 1012 * This case can happen if the user changed the MTU 1013 * of an interface after enabling IP on it. Because 1014 * most netifs don't keep track of routes pointing to 1015 * them, there is no way for one to update all its 1016 * routes when the MTU is changed. 1017 */ 1018 if ((ro->ro_rt->rt_flags & (RTF_UP | RTF_HOST)) && 1019 !(ro->ro_rt->rt_rmx.rmx_locks & RTV_MTU) && 1020 (ro->ro_rt->rt_rmx.rmx_mtu > ifp->if_mtu)) { 1021 ro->ro_rt->rt_rmx.rmx_mtu = ifp->if_mtu; 1022 } 1023 ipstat.ips_cantfrag++; 1024 goto bad; 1025 } 1026 1027 /* 1028 * Too large for interface; fragment if possible. If successful, 1029 * on return, m will point to a list of packets to be sent. 1030 */ 1031 error = ip_fragment(ip, &m, ifp->if_mtu, ifp->if_hwassist, sw_csum); 1032 if (error) 1033 goto bad; 1034 for (; m; m = m0) { 1035 m0 = m->m_nextpkt; 1036 m->m_nextpkt = 0; 1037 #ifdef IPSEC 1038 /* clean ipsec history once it goes out of the node */ 1039 ipsec_delaux(m); 1040 #endif 1041 if (error == 0) { 1042 /* Record statistics for this interface address. */ 1043 if (ia != NULL) { 1044 ia->ia_ifa.if_opackets++; 1045 ia->ia_ifa.if_obytes += m->m_pkthdr.len; 1046 } 1047 1048 error = (*ifp->if_output)(ifp, m, 1049 (struct sockaddr *)dst, ro->ro_rt); 1050 } else 1051 m_freem(m); 1052 } 1053 1054 if (error == 0) 1055 ipstat.ips_fragmented++; 1056 1057 done: 1058 #ifdef IPSEC 1059 if (ro == &iproute && ro->ro_rt) { 1060 RTFREE(ro->ro_rt); 1061 ro->ro_rt = NULL; 1062 } 1063 if (sp != NULL) { 1064 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 1065 printf("DP ip_output call free SP:%p\n", sp)); 1066 key_freesp(sp); 1067 } 1068 #endif 1069 #ifdef FAST_IPSEC 1070 if (ro == &iproute && ro->ro_rt) { 1071 RTFREE(ro->ro_rt); 1072 ro->ro_rt = NULL; 1073 } 1074 if (sp != NULL) 1075 KEY_FREESP(&sp); 1076 #endif 1077 return (error); 1078 bad: 1079 m_freem(m); 1080 goto done; 1081 } 1082 1083 /* 1084 * Create a chain of fragments which fit the given mtu. m_frag points to the 1085 * mbuf to be fragmented; on return it points to the chain with the fragments. 1086 * Return 0 if no error. If error, m_frag may contain a partially built 1087 * chain of fragments that should be freed by the caller. 1088 * 1089 * if_hwassist_flags is the hw offload capabilities (see if_data.ifi_hwassist) 1090 * sw_csum contains the delayed checksums flags (e.g., CSUM_DELAY_IP). 1091 */ 1092 int 1093 ip_fragment(struct ip *ip, struct mbuf **m_frag, int mtu, 1094 u_long if_hwassist_flags, int sw_csum) 1095 { 1096 int error = 0; 1097 int hlen = IP_VHL_HL(ip->ip_vhl) << 2; 1098 int len = (mtu - hlen) & ~7; /* size of payload in each fragment */ 1099 int off; 1100 struct mbuf *m0 = *m_frag; /* the original packet */ 1101 int firstlen; 1102 struct mbuf **mnext; 1103 int nfrags; 1104 1105 if (ip->ip_off & IP_DF) { /* Fragmentation not allowed */ 1106 ipstat.ips_cantfrag++; 1107 return EMSGSIZE; 1108 } 1109 1110 /* 1111 * Must be able to put at least 8 bytes per fragment. 1112 */ 1113 if (len < 8) 1114 return EMSGSIZE; 1115 1116 /* 1117 * If the interface will not calculate checksums on 1118 * fragmented packets, then do it here. 1119 */ 1120 if (m0->m_pkthdr.csum_flags & CSUM_DELAY_DATA && 1121 (if_hwassist_flags & CSUM_IP_FRAGS) == 0) { 1122 in_delayed_cksum(m0); 1123 m0->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA; 1124 } 1125 1126 if (len > PAGE_SIZE) { 1127 /* 1128 * Fragment large datagrams such that each segment 1129 * contains a multiple of PAGE_SIZE amount of data, 1130 * plus headers. This enables a receiver to perform 1131 * page-flipping zero-copy optimizations. 1132 * 1133 * XXX When does this help given that sender and receiver 1134 * could have different page sizes, and also mtu could 1135 * be less than the receiver's page size ? 1136 */ 1137 int newlen; 1138 struct mbuf *m; 1139 1140 for (m = m0, off = 0; m && (off+m->m_len) <= mtu; m = m->m_next) 1141 off += m->m_len; 1142 1143 /* 1144 * firstlen (off - hlen) must be aligned on an 1145 * 8-byte boundary 1146 */ 1147 if (off < hlen) 1148 goto smart_frag_failure; 1149 off = ((off - hlen) & ~7) + hlen; 1150 newlen = (~PAGE_MASK) & mtu; 1151 if ((newlen + sizeof (struct ip)) > mtu) { 1152 /* we failed, go back the default */ 1153 smart_frag_failure: 1154 newlen = len; 1155 off = hlen + len; 1156 } 1157 len = newlen; 1158 1159 } else { 1160 off = hlen + len; 1161 } 1162 1163 firstlen = off - hlen; 1164 mnext = &m0->m_nextpkt; /* pointer to next packet */ 1165 1166 /* 1167 * Loop through length of segment after first fragment, 1168 * make new header and copy data of each part and link onto chain. 1169 * Here, m0 is the original packet, m is the fragment being created. 1170 * The fragments are linked off the m_nextpkt of the original 1171 * packet, which after processing serves as the first fragment. 1172 */ 1173 for (nfrags = 1; off < ip->ip_len; off += len, nfrags++) { 1174 struct ip *mhip; /* ip header on the fragment */ 1175 struct mbuf *m; 1176 int mhlen = sizeof (struct ip); 1177 1178 MGETHDR(m, M_DONTWAIT, MT_HEADER); 1179 if (m == 0) { 1180 error = ENOBUFS; 1181 ipstat.ips_odropped++; 1182 goto done; 1183 } 1184 m->m_flags |= (m0->m_flags & M_MCAST) | M_FRAG; 1185 /* 1186 * In the first mbuf, leave room for the link header, then 1187 * copy the original IP header including options. The payload 1188 * goes into an additional mbuf chain returned by m_copy(). 1189 */ 1190 m->m_data += max_linkhdr; 1191 mhip = mtod(m, struct ip *); 1192 *mhip = *ip; 1193 if (hlen > sizeof (struct ip)) { 1194 mhlen = ip_optcopy(ip, mhip) + sizeof (struct ip); 1195 mhip->ip_vhl = IP_MAKE_VHL(IPVERSION, mhlen >> 2); 1196 } 1197 m->m_len = mhlen; 1198 /* XXX do we need to add ip->ip_off below ? */ 1199 mhip->ip_off = ((off - hlen) >> 3) + ip->ip_off; 1200 if (off + len >= ip->ip_len) { /* last fragment */ 1201 len = ip->ip_len - off; 1202 m->m_flags |= M_LASTFRAG; 1203 } else 1204 mhip->ip_off |= IP_MF; 1205 mhip->ip_len = htons((u_short)(len + mhlen)); 1206 m->m_next = m_copy(m0, off, len); 1207 if (m->m_next == 0) { /* copy failed */ 1208 m_free(m); 1209 error = ENOBUFS; /* ??? */ 1210 ipstat.ips_odropped++; 1211 goto done; 1212 } 1213 m->m_pkthdr.len = mhlen + len; 1214 m->m_pkthdr.rcvif = (struct ifnet *)0; 1215 m->m_pkthdr.csum_flags = m0->m_pkthdr.csum_flags; 1216 mhip->ip_off = htons(mhip->ip_off); 1217 mhip->ip_sum = 0; 1218 if (sw_csum & CSUM_DELAY_IP) 1219 mhip->ip_sum = in_cksum(m, mhlen); 1220 *mnext = m; 1221 mnext = &m->m_nextpkt; 1222 } 1223 ipstat.ips_ofragments += nfrags; 1224 1225 /* set first marker for fragment chain */ 1226 m0->m_flags |= M_FIRSTFRAG | M_FRAG; 1227 m0->m_pkthdr.csum_data = nfrags; 1228 1229 /* 1230 * Update first fragment by trimming what's been copied out 1231 * and updating header. 1232 */ 1233 m_adj(m0, hlen + firstlen - ip->ip_len); 1234 m0->m_pkthdr.len = hlen + firstlen; 1235 ip->ip_len = htons((u_short)m0->m_pkthdr.len); 1236 ip->ip_off |= IP_MF; 1237 ip->ip_off = htons(ip->ip_off); 1238 ip->ip_sum = 0; 1239 if (sw_csum & CSUM_DELAY_IP) 1240 ip->ip_sum = in_cksum(m0, hlen); 1241 1242 done: 1243 *m_frag = m0; 1244 return error; 1245 } 1246 1247 void 1248 in_delayed_cksum(struct mbuf *m) 1249 { 1250 struct ip *ip; 1251 u_short csum, offset; 1252 1253 ip = mtod(m, struct ip *); 1254 offset = IP_VHL_HL(ip->ip_vhl) << 2 ; 1255 csum = in_cksum_skip(m, ip->ip_len, offset); 1256 if (m->m_pkthdr.csum_flags & CSUM_UDP && csum == 0) 1257 csum = 0xffff; 1258 offset += m->m_pkthdr.csum_data; /* checksum offset */ 1259 1260 if (offset + sizeof(u_short) > m->m_len) { 1261 printf("delayed m_pullup, m->len: %d off: %d p: %d\n", 1262 m->m_len, offset, ip->ip_p); 1263 /* 1264 * XXX 1265 * this shouldn't happen, but if it does, the 1266 * correct behavior may be to insert the checksum 1267 * in the existing chain instead of rearranging it. 1268 */ 1269 m = m_pullup(m, offset + sizeof(u_short)); 1270 } 1271 *(u_short *)(m->m_data + offset) = csum; 1272 } 1273 1274 /* 1275 * Insert IP options into preformed packet. 1276 * Adjust IP destination as required for IP source routing, 1277 * as indicated by a non-zero in_addr at the start of the options. 1278 * 1279 * XXX This routine assumes that the packet has no options in place. 1280 */ 1281 static struct mbuf * 1282 ip_insertoptions(m, opt, phlen) 1283 register struct mbuf *m; 1284 struct mbuf *opt; 1285 int *phlen; 1286 { 1287 register struct ipoption *p = mtod(opt, struct ipoption *); 1288 struct mbuf *n; 1289 register struct ip *ip = mtod(m, struct ip *); 1290 unsigned optlen; 1291 1292 optlen = opt->m_len - sizeof(p->ipopt_dst); 1293 if (optlen + (u_short)ip->ip_len > IP_MAXPACKET) { 1294 *phlen = 0; 1295 return (m); /* XXX should fail */ 1296 } 1297 if (p->ipopt_dst.s_addr) 1298 ip->ip_dst = p->ipopt_dst; 1299 if (m->m_flags & M_EXT || m->m_data - optlen < m->m_pktdat) { 1300 MGETHDR(n, M_DONTWAIT, MT_HEADER); 1301 if (n == 0) { 1302 *phlen = 0; 1303 return (m); 1304 } 1305 n->m_pkthdr.rcvif = (struct ifnet *)0; 1306 n->m_pkthdr.len = m->m_pkthdr.len + optlen; 1307 m->m_len -= sizeof(struct ip); 1308 m->m_data += sizeof(struct ip); 1309 n->m_next = m; 1310 m = n; 1311 m->m_len = optlen + sizeof(struct ip); 1312 m->m_data += max_linkhdr; 1313 (void)memcpy(mtod(m, void *), ip, sizeof(struct ip)); 1314 } else { 1315 m->m_data -= optlen; 1316 m->m_len += optlen; 1317 m->m_pkthdr.len += optlen; 1318 ovbcopy((caddr_t)ip, mtod(m, caddr_t), sizeof(struct ip)); 1319 } 1320 ip = mtod(m, struct ip *); 1321 bcopy(p->ipopt_list, ip + 1, optlen); 1322 *phlen = sizeof(struct ip) + optlen; 1323 ip->ip_vhl = IP_MAKE_VHL(IPVERSION, *phlen >> 2); 1324 ip->ip_len += optlen; 1325 return (m); 1326 } 1327 1328 /* 1329 * Copy options from ip to jp, 1330 * omitting those not copied during fragmentation. 1331 */ 1332 int 1333 ip_optcopy(ip, jp) 1334 struct ip *ip, *jp; 1335 { 1336 register u_char *cp, *dp; 1337 int opt, optlen, cnt; 1338 1339 cp = (u_char *)(ip + 1); 1340 dp = (u_char *)(jp + 1); 1341 cnt = (IP_VHL_HL(ip->ip_vhl) << 2) - sizeof (struct ip); 1342 for (; cnt > 0; cnt -= optlen, cp += optlen) { 1343 opt = cp[0]; 1344 if (opt == IPOPT_EOL) 1345 break; 1346 if (opt == IPOPT_NOP) { 1347 /* Preserve for IP mcast tunnel's LSRR alignment. */ 1348 *dp++ = IPOPT_NOP; 1349 optlen = 1; 1350 continue; 1351 } 1352 1353 KASSERT(cnt >= IPOPT_OLEN + sizeof(*cp), 1354 ("ip_optcopy: malformed ipv4 option")); 1355 optlen = cp[IPOPT_OLEN]; 1356 KASSERT(optlen >= IPOPT_OLEN + sizeof(*cp) && optlen <= cnt, 1357 ("ip_optcopy: malformed ipv4 option")); 1358 1359 /* bogus lengths should have been caught by ip_dooptions */ 1360 if (optlen > cnt) 1361 optlen = cnt; 1362 if (IPOPT_COPIED(opt)) { 1363 bcopy(cp, dp, optlen); 1364 dp += optlen; 1365 } 1366 } 1367 for (optlen = dp - (u_char *)(jp+1); optlen & 0x3; optlen++) 1368 *dp++ = IPOPT_EOL; 1369 return (optlen); 1370 } 1371 1372 /* 1373 * IP socket option processing. 1374 */ 1375 int 1376 ip_ctloutput(so, sopt) 1377 struct socket *so; 1378 struct sockopt *sopt; 1379 { 1380 struct inpcb *inp = sotoinpcb(so); 1381 int error, optval; 1382 1383 error = optval = 0; 1384 if (sopt->sopt_level != IPPROTO_IP) { 1385 return (EINVAL); 1386 } 1387 1388 switch (sopt->sopt_dir) { 1389 case SOPT_SET: 1390 switch (sopt->sopt_name) { 1391 case IP_OPTIONS: 1392 #ifdef notyet 1393 case IP_RETOPTS: 1394 #endif 1395 { 1396 struct mbuf *m; 1397 if (sopt->sopt_valsize > MLEN) { 1398 error = EMSGSIZE; 1399 break; 1400 } 1401 MGET(m, sopt->sopt_p ? M_WAIT : M_DONTWAIT, MT_HEADER); 1402 if (m == 0) { 1403 error = ENOBUFS; 1404 break; 1405 } 1406 m->m_len = sopt->sopt_valsize; 1407 error = sooptcopyin(sopt, mtod(m, char *), m->m_len, 1408 m->m_len); 1409 1410 return (ip_pcbopts(sopt->sopt_name, &inp->inp_options, 1411 m)); 1412 } 1413 1414 case IP_TOS: 1415 case IP_TTL: 1416 case IP_RECVOPTS: 1417 case IP_RECVRETOPTS: 1418 case IP_RECVDSTADDR: 1419 case IP_RECVIF: 1420 case IP_FAITH: 1421 case IP_ONESBCAST: 1422 error = sooptcopyin(sopt, &optval, sizeof optval, 1423 sizeof optval); 1424 if (error) 1425 break; 1426 1427 switch (sopt->sopt_name) { 1428 case IP_TOS: 1429 inp->inp_ip_tos = optval; 1430 break; 1431 1432 case IP_TTL: 1433 inp->inp_ip_ttl = optval; 1434 break; 1435 #define OPTSET(bit) \ 1436 if (optval) \ 1437 inp->inp_flags |= bit; \ 1438 else \ 1439 inp->inp_flags &= ~bit; 1440 1441 case IP_RECVOPTS: 1442 OPTSET(INP_RECVOPTS); 1443 break; 1444 1445 case IP_RECVRETOPTS: 1446 OPTSET(INP_RECVRETOPTS); 1447 break; 1448 1449 case IP_RECVDSTADDR: 1450 OPTSET(INP_RECVDSTADDR); 1451 break; 1452 1453 case IP_RECVIF: 1454 OPTSET(INP_RECVIF); 1455 break; 1456 1457 case IP_FAITH: 1458 OPTSET(INP_FAITH); 1459 break; 1460 1461 case IP_ONESBCAST: 1462 OPTSET(INP_ONESBCAST); 1463 break; 1464 } 1465 break; 1466 #undef OPTSET 1467 1468 case IP_MULTICAST_IF: 1469 case IP_MULTICAST_VIF: 1470 case IP_MULTICAST_TTL: 1471 case IP_MULTICAST_LOOP: 1472 case IP_ADD_MEMBERSHIP: 1473 case IP_DROP_MEMBERSHIP: 1474 error = ip_setmoptions(sopt, &inp->inp_moptions); 1475 break; 1476 1477 case IP_PORTRANGE: 1478 error = sooptcopyin(sopt, &optval, sizeof optval, 1479 sizeof optval); 1480 if (error) 1481 break; 1482 1483 switch (optval) { 1484 case IP_PORTRANGE_DEFAULT: 1485 inp->inp_flags &= ~(INP_LOWPORT); 1486 inp->inp_flags &= ~(INP_HIGHPORT); 1487 break; 1488 1489 case IP_PORTRANGE_HIGH: 1490 inp->inp_flags &= ~(INP_LOWPORT); 1491 inp->inp_flags |= INP_HIGHPORT; 1492 break; 1493 1494 case IP_PORTRANGE_LOW: 1495 inp->inp_flags &= ~(INP_HIGHPORT); 1496 inp->inp_flags |= INP_LOWPORT; 1497 break; 1498 1499 default: 1500 error = EINVAL; 1501 break; 1502 } 1503 break; 1504 1505 #if defined(IPSEC) || defined(FAST_IPSEC) 1506 case IP_IPSEC_POLICY: 1507 { 1508 caddr_t req; 1509 size_t len = 0; 1510 int priv; 1511 struct mbuf *m; 1512 int optname; 1513 1514 if ((error = soopt_getm(sopt, &m)) != 0) /* XXX */ 1515 break; 1516 if ((error = soopt_mcopyin(sopt, m)) != 0) /* XXX */ 1517 break; 1518 priv = (sopt->sopt_p != NULL && 1519 suser(sopt->sopt_p) != 0) ? 0 : 1; 1520 req = mtod(m, caddr_t); 1521 len = m->m_len; 1522 optname = sopt->sopt_name; 1523 error = ipsec4_set_policy(inp, optname, req, len, priv); 1524 m_freem(m); 1525 break; 1526 } 1527 #endif /*IPSEC*/ 1528 1529 default: 1530 error = ENOPROTOOPT; 1531 break; 1532 } 1533 break; 1534 1535 case SOPT_GET: 1536 switch (sopt->sopt_name) { 1537 case IP_OPTIONS: 1538 case IP_RETOPTS: 1539 if (inp->inp_options) 1540 error = sooptcopyout(sopt, 1541 mtod(inp->inp_options, 1542 char *), 1543 inp->inp_options->m_len); 1544 else 1545 sopt->sopt_valsize = 0; 1546 break; 1547 1548 case IP_TOS: 1549 case IP_TTL: 1550 case IP_RECVOPTS: 1551 case IP_RECVRETOPTS: 1552 case IP_RECVDSTADDR: 1553 case IP_RECVIF: 1554 case IP_PORTRANGE: 1555 case IP_FAITH: 1556 case IP_ONESBCAST: 1557 switch (sopt->sopt_name) { 1558 1559 case IP_TOS: 1560 optval = inp->inp_ip_tos; 1561 break; 1562 1563 case IP_TTL: 1564 optval = inp->inp_ip_ttl; 1565 break; 1566 1567 #define OPTBIT(bit) (inp->inp_flags & bit ? 1 : 0) 1568 1569 case IP_RECVOPTS: 1570 optval = OPTBIT(INP_RECVOPTS); 1571 break; 1572 1573 case IP_RECVRETOPTS: 1574 optval = OPTBIT(INP_RECVRETOPTS); 1575 break; 1576 1577 case IP_RECVDSTADDR: 1578 optval = OPTBIT(INP_RECVDSTADDR); 1579 break; 1580 1581 case IP_RECVIF: 1582 optval = OPTBIT(INP_RECVIF); 1583 break; 1584 1585 case IP_PORTRANGE: 1586 if (inp->inp_flags & INP_HIGHPORT) 1587 optval = IP_PORTRANGE_HIGH; 1588 else if (inp->inp_flags & INP_LOWPORT) 1589 optval = IP_PORTRANGE_LOW; 1590 else 1591 optval = 0; 1592 break; 1593 1594 case IP_FAITH: 1595 optval = OPTBIT(INP_FAITH); 1596 break; 1597 1598 case IP_ONESBCAST: 1599 optval = OPTBIT(INP_ONESBCAST); 1600 break; 1601 } 1602 error = sooptcopyout(sopt, &optval, sizeof optval); 1603 break; 1604 1605 case IP_MULTICAST_IF: 1606 case IP_MULTICAST_VIF: 1607 case IP_MULTICAST_TTL: 1608 case IP_MULTICAST_LOOP: 1609 case IP_ADD_MEMBERSHIP: 1610 case IP_DROP_MEMBERSHIP: 1611 error = ip_getmoptions(sopt, inp->inp_moptions); 1612 break; 1613 1614 #if defined(IPSEC) || defined(FAST_IPSEC) 1615 case IP_IPSEC_POLICY: 1616 { 1617 struct mbuf *m = NULL; 1618 caddr_t req = NULL; 1619 size_t len = 0; 1620 1621 if (m != 0) { 1622 req = mtod(m, caddr_t); 1623 len = m->m_len; 1624 } 1625 error = ipsec4_get_policy(sotoinpcb(so), req, len, &m); 1626 if (error == 0) 1627 error = soopt_mcopyout(sopt, m); /* XXX */ 1628 if (error == 0) 1629 m_freem(m); 1630 break; 1631 } 1632 #endif /*IPSEC*/ 1633 1634 default: 1635 error = ENOPROTOOPT; 1636 break; 1637 } 1638 break; 1639 } 1640 return (error); 1641 } 1642 1643 /* 1644 * Set up IP options in pcb for insertion in output packets. 1645 * Store in mbuf with pointer in pcbopt, adding pseudo-option 1646 * with destination address if source routed. 1647 */ 1648 static int 1649 ip_pcbopts(optname, pcbopt, m) 1650 int optname; 1651 struct mbuf **pcbopt; 1652 register struct mbuf *m; 1653 { 1654 register int cnt, optlen; 1655 register u_char *cp; 1656 u_char opt; 1657 1658 /* turn off any old options */ 1659 if (*pcbopt) 1660 (void)m_free(*pcbopt); 1661 *pcbopt = 0; 1662 if (m == (struct mbuf *)0 || m->m_len == 0) { 1663 /* 1664 * Only turning off any previous options. 1665 */ 1666 if (m) 1667 (void)m_free(m); 1668 return (0); 1669 } 1670 1671 if (m->m_len % sizeof(int32_t)) 1672 goto bad; 1673 /* 1674 * IP first-hop destination address will be stored before 1675 * actual options; move other options back 1676 * and clear it when none present. 1677 */ 1678 if (m->m_data + m->m_len + sizeof(struct in_addr) >= &m->m_dat[MLEN]) 1679 goto bad; 1680 cnt = m->m_len; 1681 m->m_len += sizeof(struct in_addr); 1682 cp = mtod(m, u_char *) + sizeof(struct in_addr); 1683 ovbcopy(mtod(m, caddr_t), (caddr_t)cp, (unsigned)cnt); 1684 bzero(mtod(m, caddr_t), sizeof(struct in_addr)); 1685 1686 for (; cnt > 0; cnt -= optlen, cp += optlen) { 1687 opt = cp[IPOPT_OPTVAL]; 1688 if (opt == IPOPT_EOL) 1689 break; 1690 if (opt == IPOPT_NOP) 1691 optlen = 1; 1692 else { 1693 if (cnt < IPOPT_OLEN + sizeof(*cp)) 1694 goto bad; 1695 optlen = cp[IPOPT_OLEN]; 1696 if (optlen < IPOPT_OLEN + sizeof(*cp) || optlen > cnt) 1697 goto bad; 1698 } 1699 switch (opt) { 1700 1701 default: 1702 break; 1703 1704 case IPOPT_LSRR: 1705 case IPOPT_SSRR: 1706 /* 1707 * user process specifies route as: 1708 * ->A->B->C->D 1709 * D must be our final destination (but we can't 1710 * check that since we may not have connected yet). 1711 * A is first hop destination, which doesn't appear in 1712 * actual IP option, but is stored before the options. 1713 */ 1714 if (optlen < IPOPT_MINOFF - 1 + sizeof(struct in_addr)) 1715 goto bad; 1716 m->m_len -= sizeof(struct in_addr); 1717 cnt -= sizeof(struct in_addr); 1718 optlen -= sizeof(struct in_addr); 1719 cp[IPOPT_OLEN] = optlen; 1720 /* 1721 * Move first hop before start of options. 1722 */ 1723 bcopy((caddr_t)&cp[IPOPT_OFFSET+1], mtod(m, caddr_t), 1724 sizeof(struct in_addr)); 1725 /* 1726 * Then copy rest of options back 1727 * to close up the deleted entry. 1728 */ 1729 ovbcopy((caddr_t)(&cp[IPOPT_OFFSET+1] + 1730 sizeof(struct in_addr)), 1731 (caddr_t)&cp[IPOPT_OFFSET+1], 1732 (unsigned)cnt - (IPOPT_MINOFF - 1)); 1733 break; 1734 } 1735 } 1736 if (m->m_len > MAX_IPOPTLEN + sizeof(struct in_addr)) 1737 goto bad; 1738 *pcbopt = m; 1739 return (0); 1740 1741 bad: 1742 (void)m_free(m); 1743 return (EINVAL); 1744 } 1745 1746 /* 1747 * XXX 1748 * The whole multicast option thing needs to be re-thought. 1749 * Several of these options are equally applicable to non-multicast 1750 * transmission, and one (IP_MULTICAST_TTL) totally duplicates a 1751 * standard option (IP_TTL). 1752 */ 1753 1754 /* 1755 * following RFC1724 section 3.3, 0.0.0.0/8 is interpreted as interface index. 1756 */ 1757 static struct ifnet * 1758 ip_multicast_if(a, ifindexp) 1759 struct in_addr *a; 1760 int *ifindexp; 1761 { 1762 int ifindex; 1763 struct ifnet *ifp; 1764 1765 if (ifindexp) 1766 *ifindexp = 0; 1767 if (ntohl(a->s_addr) >> 24 == 0) { 1768 ifindex = ntohl(a->s_addr) & 0xffffff; 1769 if (ifindex < 0 || if_index < ifindex) 1770 return NULL; 1771 ifp = ifindex2ifnet[ifindex]; 1772 if (ifindexp) 1773 *ifindexp = ifindex; 1774 } else { 1775 INADDR_TO_IFP(*a, ifp); 1776 } 1777 return ifp; 1778 } 1779 1780 /* 1781 * Set the IP multicast options in response to user setsockopt(). 1782 */ 1783 static int 1784 ip_setmoptions(sopt, imop) 1785 struct sockopt *sopt; 1786 struct ip_moptions **imop; 1787 { 1788 int error = 0; 1789 int i; 1790 struct in_addr addr; 1791 struct ip_mreq mreq; 1792 struct ifnet *ifp; 1793 struct ip_moptions *imo = *imop; 1794 struct route ro; 1795 struct sockaddr_in *dst; 1796 int ifindex; 1797 int s; 1798 1799 if (imo == NULL) { 1800 /* 1801 * No multicast option buffer attached to the pcb; 1802 * allocate one and initialize to default values. 1803 */ 1804 imo = (struct ip_moptions*)malloc(sizeof(*imo), M_IPMOPTS, 1805 M_WAITOK); 1806 1807 if (imo == NULL) 1808 return (ENOBUFS); 1809 *imop = imo; 1810 imo->imo_multicast_ifp = NULL; 1811 imo->imo_multicast_addr.s_addr = INADDR_ANY; 1812 imo->imo_multicast_vif = -1; 1813 imo->imo_multicast_ttl = IP_DEFAULT_MULTICAST_TTL; 1814 imo->imo_multicast_loop = IP_DEFAULT_MULTICAST_LOOP; 1815 imo->imo_num_memberships = 0; 1816 } 1817 1818 switch (sopt->sopt_name) { 1819 /* store an index number for the vif you wanna use in the send */ 1820 case IP_MULTICAST_VIF: 1821 if (legal_vif_num == 0) { 1822 error = EOPNOTSUPP; 1823 break; 1824 } 1825 error = sooptcopyin(sopt, &i, sizeof i, sizeof i); 1826 if (error) 1827 break; 1828 if (!legal_vif_num(i) && (i != -1)) { 1829 error = EINVAL; 1830 break; 1831 } 1832 imo->imo_multicast_vif = i; 1833 break; 1834 1835 case IP_MULTICAST_IF: 1836 /* 1837 * Select the interface for outgoing multicast packets. 1838 */ 1839 error = sooptcopyin(sopt, &addr, sizeof addr, sizeof addr); 1840 if (error) 1841 break; 1842 /* 1843 * INADDR_ANY is used to remove a previous selection. 1844 * When no interface is selected, a default one is 1845 * chosen every time a multicast packet is sent. 1846 */ 1847 if (addr.s_addr == INADDR_ANY) { 1848 imo->imo_multicast_ifp = NULL; 1849 break; 1850 } 1851 /* 1852 * The selected interface is identified by its local 1853 * IP address. Find the interface and confirm that 1854 * it supports multicasting. 1855 */ 1856 s = splimp(); 1857 ifp = ip_multicast_if(&addr, &ifindex); 1858 if (ifp == NULL || (ifp->if_flags & IFF_MULTICAST) == 0) { 1859 splx(s); 1860 error = EADDRNOTAVAIL; 1861 break; 1862 } 1863 imo->imo_multicast_ifp = ifp; 1864 if (ifindex) 1865 imo->imo_multicast_addr = addr; 1866 else 1867 imo->imo_multicast_addr.s_addr = INADDR_ANY; 1868 splx(s); 1869 break; 1870 1871 case IP_MULTICAST_TTL: 1872 /* 1873 * Set the IP time-to-live for outgoing multicast packets. 1874 * The original multicast API required a char argument, 1875 * which is inconsistent with the rest of the socket API. 1876 * We allow either a char or an int. 1877 */ 1878 if (sopt->sopt_valsize == 1) { 1879 u_char ttl; 1880 error = sooptcopyin(sopt, &ttl, 1, 1); 1881 if (error) 1882 break; 1883 imo->imo_multicast_ttl = ttl; 1884 } else { 1885 u_int ttl; 1886 error = sooptcopyin(sopt, &ttl, sizeof ttl, 1887 sizeof ttl); 1888 if (error) 1889 break; 1890 if (ttl > 255) 1891 error = EINVAL; 1892 else 1893 imo->imo_multicast_ttl = ttl; 1894 } 1895 break; 1896 1897 case IP_MULTICAST_LOOP: 1898 /* 1899 * Set the loopback flag for outgoing multicast packets. 1900 * Must be zero or one. The original multicast API required a 1901 * char argument, which is inconsistent with the rest 1902 * of the socket API. We allow either a char or an int. 1903 */ 1904 if (sopt->sopt_valsize == 1) { 1905 u_char loop; 1906 error = sooptcopyin(sopt, &loop, 1, 1); 1907 if (error) 1908 break; 1909 imo->imo_multicast_loop = !!loop; 1910 } else { 1911 u_int loop; 1912 error = sooptcopyin(sopt, &loop, sizeof loop, 1913 sizeof loop); 1914 if (error) 1915 break; 1916 imo->imo_multicast_loop = !!loop; 1917 } 1918 break; 1919 1920 case IP_ADD_MEMBERSHIP: 1921 /* 1922 * Add a multicast group membership. 1923 * Group must be a valid IP multicast address. 1924 */ 1925 error = sooptcopyin(sopt, &mreq, sizeof mreq, sizeof mreq); 1926 if (error) 1927 break; 1928 1929 if (!IN_MULTICAST(ntohl(mreq.imr_multiaddr.s_addr))) { 1930 error = EINVAL; 1931 break; 1932 } 1933 s = splimp(); 1934 /* 1935 * If no interface address was provided, use the interface of 1936 * the route to the given multicast address. 1937 */ 1938 if (mreq.imr_interface.s_addr == INADDR_ANY) { 1939 bzero((caddr_t)&ro, sizeof(ro)); 1940 dst = (struct sockaddr_in *)&ro.ro_dst; 1941 dst->sin_len = sizeof(*dst); 1942 dst->sin_family = AF_INET; 1943 dst->sin_addr = mreq.imr_multiaddr; 1944 rtalloc(&ro); 1945 if (ro.ro_rt == NULL) { 1946 error = EADDRNOTAVAIL; 1947 splx(s); 1948 break; 1949 } 1950 ifp = ro.ro_rt->rt_ifp; 1951 rtfree(ro.ro_rt); 1952 } 1953 else { 1954 ifp = ip_multicast_if(&mreq.imr_interface, NULL); 1955 } 1956 1957 /* 1958 * See if we found an interface, and confirm that it 1959 * supports multicast. 1960 */ 1961 if (ifp == NULL || (ifp->if_flags & IFF_MULTICAST) == 0) { 1962 error = EADDRNOTAVAIL; 1963 splx(s); 1964 break; 1965 } 1966 /* 1967 * See if the membership already exists or if all the 1968 * membership slots are full. 1969 */ 1970 for (i = 0; i < imo->imo_num_memberships; ++i) { 1971 if (imo->imo_membership[i]->inm_ifp == ifp && 1972 imo->imo_membership[i]->inm_addr.s_addr 1973 == mreq.imr_multiaddr.s_addr) 1974 break; 1975 } 1976 if (i < imo->imo_num_memberships) { 1977 error = EADDRINUSE; 1978 splx(s); 1979 break; 1980 } 1981 if (i == IP_MAX_MEMBERSHIPS) { 1982 error = ETOOMANYREFS; 1983 splx(s); 1984 break; 1985 } 1986 /* 1987 * Everything looks good; add a new record to the multicast 1988 * address list for the given interface. 1989 */ 1990 if ((imo->imo_membership[i] = 1991 in_addmulti(&mreq.imr_multiaddr, ifp)) == NULL) { 1992 error = ENOBUFS; 1993 splx(s); 1994 break; 1995 } 1996 ++imo->imo_num_memberships; 1997 splx(s); 1998 break; 1999 2000 case IP_DROP_MEMBERSHIP: 2001 /* 2002 * Drop a multicast group membership. 2003 * Group must be a valid IP multicast address. 2004 */ 2005 error = sooptcopyin(sopt, &mreq, sizeof mreq, sizeof mreq); 2006 if (error) 2007 break; 2008 2009 if (!IN_MULTICAST(ntohl(mreq.imr_multiaddr.s_addr))) { 2010 error = EINVAL; 2011 break; 2012 } 2013 2014 s = splimp(); 2015 /* 2016 * If an interface address was specified, get a pointer 2017 * to its ifnet structure. 2018 */ 2019 if (mreq.imr_interface.s_addr == INADDR_ANY) 2020 ifp = NULL; 2021 else { 2022 ifp = ip_multicast_if(&mreq.imr_interface, NULL); 2023 if (ifp == NULL) { 2024 error = EADDRNOTAVAIL; 2025 splx(s); 2026 break; 2027 } 2028 } 2029 /* 2030 * Find the membership in the membership array. 2031 */ 2032 for (i = 0; i < imo->imo_num_memberships; ++i) { 2033 if ((ifp == NULL || 2034 imo->imo_membership[i]->inm_ifp == ifp) && 2035 imo->imo_membership[i]->inm_addr.s_addr == 2036 mreq.imr_multiaddr.s_addr) 2037 break; 2038 } 2039 if (i == imo->imo_num_memberships) { 2040 error = EADDRNOTAVAIL; 2041 splx(s); 2042 break; 2043 } 2044 /* 2045 * Give up the multicast address record to which the 2046 * membership points. 2047 */ 2048 in_delmulti(imo->imo_membership[i]); 2049 /* 2050 * Remove the gap in the membership array. 2051 */ 2052 for (++i; i < imo->imo_num_memberships; ++i) 2053 imo->imo_membership[i-1] = imo->imo_membership[i]; 2054 --imo->imo_num_memberships; 2055 splx(s); 2056 break; 2057 2058 default: 2059 error = EOPNOTSUPP; 2060 break; 2061 } 2062 2063 /* 2064 * If all options have default values, no need to keep the mbuf. 2065 */ 2066 if (imo->imo_multicast_ifp == NULL && 2067 imo->imo_multicast_vif == -1 && 2068 imo->imo_multicast_ttl == IP_DEFAULT_MULTICAST_TTL && 2069 imo->imo_multicast_loop == IP_DEFAULT_MULTICAST_LOOP && 2070 imo->imo_num_memberships == 0) { 2071 free(*imop, M_IPMOPTS); 2072 *imop = NULL; 2073 } 2074 2075 return (error); 2076 } 2077 2078 /* 2079 * Return the IP multicast options in response to user getsockopt(). 2080 */ 2081 static int 2082 ip_getmoptions(sopt, imo) 2083 struct sockopt *sopt; 2084 register struct ip_moptions *imo; 2085 { 2086 struct in_addr addr; 2087 struct in_ifaddr *ia; 2088 int error, optval; 2089 u_char coptval; 2090 2091 error = 0; 2092 switch (sopt->sopt_name) { 2093 case IP_MULTICAST_VIF: 2094 if (imo != NULL) 2095 optval = imo->imo_multicast_vif; 2096 else 2097 optval = -1; 2098 error = sooptcopyout(sopt, &optval, sizeof optval); 2099 break; 2100 2101 case IP_MULTICAST_IF: 2102 if (imo == NULL || imo->imo_multicast_ifp == NULL) 2103 addr.s_addr = INADDR_ANY; 2104 else if (imo->imo_multicast_addr.s_addr) { 2105 /* return the value user has set */ 2106 addr = imo->imo_multicast_addr; 2107 } else { 2108 IFP_TO_IA(imo->imo_multicast_ifp, ia); 2109 addr.s_addr = (ia == NULL) ? INADDR_ANY 2110 : IA_SIN(ia)->sin_addr.s_addr; 2111 } 2112 error = sooptcopyout(sopt, &addr, sizeof addr); 2113 break; 2114 2115 case IP_MULTICAST_TTL: 2116 if (imo == 0) 2117 optval = coptval = IP_DEFAULT_MULTICAST_TTL; 2118 else 2119 optval = coptval = imo->imo_multicast_ttl; 2120 if (sopt->sopt_valsize == 1) 2121 error = sooptcopyout(sopt, &coptval, 1); 2122 else 2123 error = sooptcopyout(sopt, &optval, sizeof optval); 2124 break; 2125 2126 case IP_MULTICAST_LOOP: 2127 if (imo == 0) 2128 optval = coptval = IP_DEFAULT_MULTICAST_LOOP; 2129 else 2130 optval = coptval = imo->imo_multicast_loop; 2131 if (sopt->sopt_valsize == 1) 2132 error = sooptcopyout(sopt, &coptval, 1); 2133 else 2134 error = sooptcopyout(sopt, &optval, sizeof optval); 2135 break; 2136 2137 default: 2138 error = ENOPROTOOPT; 2139 break; 2140 } 2141 return (error); 2142 } 2143 2144 /* 2145 * Discard the IP multicast options. 2146 */ 2147 void 2148 ip_freemoptions(imo) 2149 register struct ip_moptions *imo; 2150 { 2151 register int i; 2152 2153 if (imo != NULL) { 2154 for (i = 0; i < imo->imo_num_memberships; ++i) 2155 in_delmulti(imo->imo_membership[i]); 2156 free(imo, M_IPMOPTS); 2157 } 2158 } 2159 2160 /* 2161 * Routine called from ip_output() to loop back a copy of an IP multicast 2162 * packet to the input queue of a specified interface. Note that this 2163 * calls the output routine of the loopback "driver", but with an interface 2164 * pointer that might NOT be a loopback interface -- evil, but easier than 2165 * replicating that code here. 2166 */ 2167 static void 2168 ip_mloopback(ifp, m, dst, hlen) 2169 struct ifnet *ifp; 2170 register struct mbuf *m; 2171 register struct sockaddr_in *dst; 2172 int hlen; 2173 { 2174 register struct ip *ip; 2175 struct mbuf *copym; 2176 2177 copym = m_copy(m, 0, M_COPYALL); 2178 if (copym != NULL && (copym->m_flags & M_EXT || copym->m_len < hlen)) 2179 copym = m_pullup(copym, hlen); 2180 if (copym != NULL) { 2181 /* If needed, compute the checksum and mark it as valid. */ 2182 if (copym->m_pkthdr.csum_flags & CSUM_DELAY_DATA) { 2183 in_delayed_cksum(copym); 2184 copym->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA; 2185 copym->m_pkthdr.csum_flags |= 2186 CSUM_DATA_VALID | CSUM_PSEUDO_HDR; 2187 copym->m_pkthdr.csum_data = 0xffff; 2188 } 2189 /* 2190 * We don't bother to fragment if the IP length is greater 2191 * than the interface's MTU. Can this possibly matter? 2192 */ 2193 ip = mtod(copym, struct ip *); 2194 ip->ip_len = htons(ip->ip_len); 2195 ip->ip_off = htons(ip->ip_off); 2196 ip->ip_sum = 0; 2197 if (ip->ip_vhl == IP_VHL_BORING) { 2198 ip->ip_sum = in_cksum_hdr(ip); 2199 } else { 2200 ip->ip_sum = in_cksum(copym, hlen); 2201 } 2202 /* 2203 * NB: 2204 * It's not clear whether there are any lingering 2205 * reentrancy problems in other areas which might 2206 * be exposed by using ip_input directly (in 2207 * particular, everything which modifies the packet 2208 * in-place). Yet another option is using the 2209 * protosw directly to deliver the looped back 2210 * packet. For the moment, we'll err on the side 2211 * of safety by using if_simloop(). 2212 */ 2213 #if 1 /* XXX */ 2214 if (dst->sin_family != AF_INET) { 2215 printf("ip_mloopback: bad address family %d\n", 2216 dst->sin_family); 2217 dst->sin_family = AF_INET; 2218 } 2219 #endif 2220 2221 #ifdef notdef 2222 copym->m_pkthdr.rcvif = ifp; 2223 ip_input(copym); 2224 #else 2225 if_simloop(ifp, copym, dst->sin_family, 0); 2226 #endif 2227 } 2228 }
Cache object: 21e8deb08c99050afc99ecd3ac7abee8
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