1 /* $NetBSD: ip_output.c,v 1.140 2005/02/03 23:13:20 perry Exp $ */ 2 3 /* 4 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the project nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 /*- 33 * Copyright (c) 1998 The NetBSD Foundation, Inc. 34 * All rights reserved. 35 * 36 * This code is derived from software contributed to The NetBSD Foundation 37 * by Public Access Networks Corporation ("Panix"). It was developed under 38 * contract to Panix by Eric Haszlakiewicz and Thor Lancelot Simon. 39 * 40 * Redistribution and use in source and binary forms, with or without 41 * modification, are permitted provided that the following conditions 42 * are met: 43 * 1. Redistributions of source code must retain the above copyright 44 * notice, this list of conditions and the following disclaimer. 45 * 2. Redistributions in binary form must reproduce the above copyright 46 * notice, this list of conditions and the following disclaimer in the 47 * documentation and/or other materials provided with the distribution. 48 * 3. All advertising materials mentioning features or use of this software 49 * must display the following acknowledgement: 50 * This product includes software developed by the NetBSD 51 * Foundation, Inc. and its contributors. 52 * 4. Neither the name of The NetBSD Foundation nor the names of its 53 * contributors may be used to endorse or promote products derived 54 * from this software without specific prior written permission. 55 * 56 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 57 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 58 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 59 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 60 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 61 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 62 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 63 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 64 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 65 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 66 * POSSIBILITY OF SUCH DAMAGE. 67 */ 68 69 /* 70 * Copyright (c) 1982, 1986, 1988, 1990, 1993 71 * The Regents of the University of California. All rights reserved. 72 * 73 * Redistribution and use in source and binary forms, with or without 74 * modification, are permitted provided that the following conditions 75 * are met: 76 * 1. Redistributions of source code must retain the above copyright 77 * notice, this list of conditions and the following disclaimer. 78 * 2. Redistributions in binary form must reproduce the above copyright 79 * notice, this list of conditions and the following disclaimer in the 80 * documentation and/or other materials provided with the distribution. 81 * 3. Neither the name of the University nor the names of its contributors 82 * may be used to endorse or promote products derived from this software 83 * without specific prior written permission. 84 * 85 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 86 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 87 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 88 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 89 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 90 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 91 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 92 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 93 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 94 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 95 * SUCH DAMAGE. 96 * 97 * @(#)ip_output.c 8.3 (Berkeley) 1/21/94 98 */ 99 100 #include <sys/cdefs.h> 101 __KERNEL_RCSID(0, "$NetBSD: ip_output.c,v 1.140 2005/02/03 23:13:20 perry Exp $"); 102 103 #include "opt_pfil_hooks.h" 104 #include "opt_inet.h" 105 #include "opt_ipsec.h" 106 #include "opt_mrouting.h" 107 108 #include <sys/param.h> 109 #include <sys/malloc.h> 110 #include <sys/mbuf.h> 111 #include <sys/errno.h> 112 #include <sys/protosw.h> 113 #include <sys/socket.h> 114 #include <sys/socketvar.h> 115 #ifdef FAST_IPSEC 116 #include <sys/domain.h> 117 #endif 118 #include <sys/systm.h> 119 #include <sys/proc.h> 120 121 #include <net/if.h> 122 #include <net/route.h> 123 #include <net/pfil.h> 124 125 #include <netinet/in.h> 126 #include <netinet/in_systm.h> 127 #include <netinet/ip.h> 128 #include <netinet/in_pcb.h> 129 #include <netinet/in_var.h> 130 #include <netinet/ip_var.h> 131 132 #ifdef MROUTING 133 #include <netinet/ip_mroute.h> 134 #endif 135 136 #include <machine/stdarg.h> 137 138 #ifdef IPSEC 139 #include <netinet6/ipsec.h> 140 #include <netkey/key.h> 141 #include <netkey/key_debug.h> 142 #endif /*IPSEC*/ 143 144 #ifdef FAST_IPSEC 145 #include <netipsec/ipsec.h> 146 #include <netipsec/key.h> 147 #include <netipsec/xform.h> 148 #endif /* FAST_IPSEC*/ 149 150 static struct mbuf *ip_insertoptions(struct mbuf *, struct mbuf *, int *); 151 static struct ifnet *ip_multicast_if(struct in_addr *, int *); 152 static void ip_mloopback(struct ifnet *, struct mbuf *, struct sockaddr_in *); 153 154 #ifdef PFIL_HOOKS 155 extern struct pfil_head inet_pfil_hook; /* XXX */ 156 #endif 157 158 /* 159 * IP output. The packet in mbuf chain m contains a skeletal IP 160 * header (with len, off, ttl, proto, tos, src, dst). 161 * The mbuf chain containing the packet will be freed. 162 * The mbuf opt, if present, will not be freed. 163 */ 164 int 165 ip_output(struct mbuf *m0, ...) 166 { 167 struct ip *ip; 168 struct ifnet *ifp; 169 struct mbuf *m = m0; 170 int hlen = sizeof (struct ip); 171 int len, error = 0; 172 struct route iproute; 173 struct sockaddr_in *dst; 174 struct in_ifaddr *ia; 175 struct mbuf *opt; 176 struct route *ro; 177 int flags, sw_csum; 178 int *mtu_p; 179 u_long mtu; 180 struct ip_moptions *imo; 181 struct socket *so; 182 va_list ap; 183 #ifdef IPSEC 184 struct secpolicy *sp = NULL; 185 #endif /*IPSEC*/ 186 #ifdef FAST_IPSEC 187 struct inpcb *inp; 188 struct m_tag *mtag; 189 struct secpolicy *sp = NULL; 190 struct tdb_ident *tdbi; 191 int s; 192 #endif 193 u_int16_t ip_len; 194 195 len = 0; 196 va_start(ap, m0); 197 opt = va_arg(ap, struct mbuf *); 198 ro = va_arg(ap, struct route *); 199 flags = va_arg(ap, int); 200 imo = va_arg(ap, struct ip_moptions *); 201 so = va_arg(ap, struct socket *); 202 if (flags & IP_RETURNMTU) 203 mtu_p = va_arg(ap, int *); 204 else 205 mtu_p = NULL; 206 va_end(ap); 207 208 MCLAIM(m, &ip_tx_mowner); 209 #ifdef FAST_IPSEC 210 if (so != NULL && so->so_proto->pr_domain->dom_family == AF_INET) 211 inp = (struct inpcb *)so->so_pcb; 212 else 213 inp = NULL; 214 #endif /* FAST_IPSEC */ 215 216 #ifdef DIAGNOSTIC 217 if ((m->m_flags & M_PKTHDR) == 0) 218 panic("ip_output no HDR"); 219 #endif 220 if (opt) { 221 m = ip_insertoptions(m, opt, &len); 222 if (len >= sizeof(struct ip)) 223 hlen = len; 224 } 225 ip = mtod(m, struct ip *); 226 /* 227 * Fill in IP header. 228 */ 229 if ((flags & (IP_FORWARDING|IP_RAWOUTPUT)) == 0) { 230 ip->ip_v = IPVERSION; 231 ip->ip_off = htons(0); 232 ip->ip_id = ip_newid(); 233 ip->ip_hl = hlen >> 2; 234 ipstat.ips_localout++; 235 } else { 236 hlen = ip->ip_hl << 2; 237 } 238 /* 239 * Route packet. 240 */ 241 if (ro == 0) { 242 ro = &iproute; 243 bzero((caddr_t)ro, sizeof (*ro)); 244 } 245 dst = satosin(&ro->ro_dst); 246 /* 247 * If there is a cached route, 248 * check that it is to the same destination 249 * and is still up. If not, free it and try again. 250 * The address family should also be checked in case of sharing the 251 * cache with IPv6. 252 */ 253 if (ro->ro_rt && ((ro->ro_rt->rt_flags & RTF_UP) == 0 || 254 dst->sin_family != AF_INET || 255 !in_hosteq(dst->sin_addr, ip->ip_dst))) { 256 RTFREE(ro->ro_rt); 257 ro->ro_rt = (struct rtentry *)0; 258 } 259 if (ro->ro_rt == 0) { 260 bzero(dst, sizeof(*dst)); 261 dst->sin_family = AF_INET; 262 dst->sin_len = sizeof(*dst); 263 dst->sin_addr = ip->ip_dst; 264 } 265 /* 266 * If routing to interface only, 267 * short circuit routing lookup. 268 */ 269 if (flags & IP_ROUTETOIF) { 270 if ((ia = ifatoia(ifa_ifwithladdr(sintosa(dst)))) == 0) { 271 ipstat.ips_noroute++; 272 error = ENETUNREACH; 273 goto bad; 274 } 275 ifp = ia->ia_ifp; 276 mtu = ifp->if_mtu; 277 ip->ip_ttl = 1; 278 } else if ((IN_MULTICAST(ip->ip_dst.s_addr) || 279 ip->ip_dst.s_addr == INADDR_BROADCAST) && 280 imo != NULL && imo->imo_multicast_ifp != NULL) { 281 ifp = imo->imo_multicast_ifp; 282 mtu = ifp->if_mtu; 283 IFP_TO_IA(ifp, ia); 284 } else { 285 if (ro->ro_rt == 0) 286 rtalloc(ro); 287 if (ro->ro_rt == 0) { 288 ipstat.ips_noroute++; 289 error = EHOSTUNREACH; 290 goto bad; 291 } 292 ia = ifatoia(ro->ro_rt->rt_ifa); 293 ifp = ro->ro_rt->rt_ifp; 294 if ((mtu = ro->ro_rt->rt_rmx.rmx_mtu) == 0) 295 mtu = ifp->if_mtu; 296 ro->ro_rt->rt_use++; 297 if (ro->ro_rt->rt_flags & RTF_GATEWAY) 298 dst = satosin(ro->ro_rt->rt_gateway); 299 } 300 if (IN_MULTICAST(ip->ip_dst.s_addr) || 301 (ip->ip_dst.s_addr == INADDR_BROADCAST)) { 302 struct in_multi *inm; 303 304 m->m_flags |= (ip->ip_dst.s_addr == INADDR_BROADCAST) ? 305 M_BCAST : M_MCAST; 306 /* 307 * IP destination address is multicast. Make sure "dst" 308 * still points to the address in "ro". (It may have been 309 * changed to point to a gateway address, above.) 310 */ 311 dst = satosin(&ro->ro_dst); 312 /* 313 * See if the caller provided any multicast options 314 */ 315 if (imo != NULL) 316 ip->ip_ttl = imo->imo_multicast_ttl; 317 else 318 ip->ip_ttl = IP_DEFAULT_MULTICAST_TTL; 319 320 /* 321 * if we don't know the outgoing ifp yet, we can't generate 322 * output 323 */ 324 if (!ifp) { 325 ipstat.ips_noroute++; 326 error = ENETUNREACH; 327 goto bad; 328 } 329 330 /* 331 * If the packet is multicast or broadcast, confirm that 332 * the outgoing interface can transmit it. 333 */ 334 if (((m->m_flags & M_MCAST) && 335 (ifp->if_flags & IFF_MULTICAST) == 0) || 336 ((m->m_flags & M_BCAST) && 337 (ifp->if_flags & (IFF_BROADCAST|IFF_POINTOPOINT)) == 0)) { 338 ipstat.ips_noroute++; 339 error = ENETUNREACH; 340 goto bad; 341 } 342 /* 343 * If source address not specified yet, use an address 344 * of outgoing interface. 345 */ 346 if (in_nullhost(ip->ip_src)) { 347 struct in_ifaddr *ia; 348 349 IFP_TO_IA(ifp, ia); 350 if (!ia) { 351 error = EADDRNOTAVAIL; 352 goto bad; 353 } 354 ip->ip_src = ia->ia_addr.sin_addr; 355 } 356 357 IN_LOOKUP_MULTI(ip->ip_dst, ifp, inm); 358 if (inm != NULL && 359 (imo == NULL || imo->imo_multicast_loop)) { 360 /* 361 * If we belong to the destination multicast group 362 * on the outgoing interface, and the caller did not 363 * forbid loopback, loop back a copy. 364 */ 365 ip_mloopback(ifp, m, dst); 366 } 367 #ifdef MROUTING 368 else { 369 /* 370 * If we are acting as a multicast router, perform 371 * multicast forwarding as if the packet had just 372 * arrived on the interface to which we are about 373 * to send. The multicast forwarding function 374 * recursively calls this function, using the 375 * IP_FORWARDING flag to prevent infinite recursion. 376 * 377 * Multicasts that are looped back by ip_mloopback(), 378 * above, will be forwarded by the ip_input() routine, 379 * if necessary. 380 */ 381 extern struct socket *ip_mrouter; 382 383 if (ip_mrouter && (flags & IP_FORWARDING) == 0) { 384 if (ip_mforward(m, ifp) != 0) { 385 m_freem(m); 386 goto done; 387 } 388 } 389 } 390 #endif 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) != 0) { 400 m_freem(m); 401 goto done; 402 } 403 404 goto sendit; 405 } 406 #ifndef notdef 407 /* 408 * If source address not specified yet, use address 409 * of outgoing interface. 410 */ 411 if (in_nullhost(ip->ip_src)) 412 ip->ip_src = ia->ia_addr.sin_addr; 413 #endif 414 415 /* 416 * packets with Class-D address as source are not valid per 417 * RFC 1112 418 */ 419 if (IN_MULTICAST(ip->ip_src.s_addr)) { 420 ipstat.ips_odropped++; 421 error = EADDRNOTAVAIL; 422 goto bad; 423 } 424 425 /* 426 * Look for broadcast address and 427 * and verify user is allowed to send 428 * such a packet. 429 */ 430 if (in_broadcast(dst->sin_addr, ifp)) { 431 if ((ifp->if_flags & IFF_BROADCAST) == 0) { 432 error = EADDRNOTAVAIL; 433 goto bad; 434 } 435 if ((flags & IP_ALLOWBROADCAST) == 0) { 436 error = EACCES; 437 goto bad; 438 } 439 /* don't allow broadcast messages to be fragmented */ 440 if (ntohs(ip->ip_len) > ifp->if_mtu) { 441 error = EMSGSIZE; 442 goto bad; 443 } 444 m->m_flags |= M_BCAST; 445 } else 446 m->m_flags &= ~M_BCAST; 447 448 sendit: 449 /* 450 * If we're doing Path MTU Discovery, we need to set DF unless 451 * the route's MTU is locked. 452 */ 453 if ((flags & IP_MTUDISC) != 0 && ro->ro_rt != NULL && 454 (ro->ro_rt->rt_rmx.rmx_locks & RTV_MTU) == 0) 455 ip->ip_off |= htons(IP_DF); 456 457 /* Remember the current ip_len */ 458 ip_len = ntohs(ip->ip_len); 459 460 #ifdef IPSEC 461 /* get SP for this packet */ 462 if (so == NULL) 463 sp = ipsec4_getpolicybyaddr(m, IPSEC_DIR_OUTBOUND, 464 flags, &error); 465 else { 466 if (IPSEC_PCB_SKIP_IPSEC(sotoinpcb_hdr(so)->inph_sp, 467 IPSEC_DIR_OUTBOUND)) 468 goto skip_ipsec; 469 sp = ipsec4_getpolicybysock(m, IPSEC_DIR_OUTBOUND, so, &error); 470 } 471 472 if (sp == NULL) { 473 ipsecstat.out_inval++; 474 goto bad; 475 } 476 477 error = 0; 478 479 /* check policy */ 480 switch (sp->policy) { 481 case IPSEC_POLICY_DISCARD: 482 /* 483 * This packet is just discarded. 484 */ 485 ipsecstat.out_polvio++; 486 goto bad; 487 488 case IPSEC_POLICY_BYPASS: 489 case IPSEC_POLICY_NONE: 490 /* no need to do IPsec. */ 491 goto skip_ipsec; 492 493 case IPSEC_POLICY_IPSEC: 494 if (sp->req == NULL) { 495 /* XXX should be panic ? */ 496 printf("ip_output: No IPsec request specified.\n"); 497 error = EINVAL; 498 goto bad; 499 } 500 break; 501 502 case IPSEC_POLICY_ENTRUST: 503 default: 504 printf("ip_output: Invalid policy found. %d\n", sp->policy); 505 } 506 507 /* 508 * ipsec4_output() expects ip_len and ip_off in network 509 * order. They have been set to network order above. 510 */ 511 512 { 513 struct ipsec_output_state state; 514 bzero(&state, sizeof(state)); 515 state.m = m; 516 if (flags & IP_ROUTETOIF) { 517 state.ro = &iproute; 518 bzero(&iproute, sizeof(iproute)); 519 } else 520 state.ro = ro; 521 state.dst = (struct sockaddr *)dst; 522 523 /* 524 * We can't defer the checksum of payload data if 525 * we're about to encrypt/authenticate it. 526 * 527 * XXX When we support crypto offloading functions of 528 * XXX network interfaces, we need to reconsider this, 529 * XXX since it's likely that they'll support checksumming, 530 * XXX as well. 531 */ 532 if (m->m_pkthdr.csum_flags & (M_CSUM_TCPv4|M_CSUM_UDPv4)) { 533 in_delayed_cksum(m); 534 m->m_pkthdr.csum_flags &= ~(M_CSUM_TCPv4|M_CSUM_UDPv4); 535 } 536 537 error = ipsec4_output(&state, sp, flags); 538 539 m = state.m; 540 if (flags & IP_ROUTETOIF) { 541 /* 542 * if we have tunnel mode SA, we may need to ignore 543 * IP_ROUTETOIF. 544 */ 545 if (state.ro != &iproute || state.ro->ro_rt != NULL) { 546 flags &= ~IP_ROUTETOIF; 547 ro = state.ro; 548 } 549 } else 550 ro = state.ro; 551 dst = (struct sockaddr_in *)state.dst; 552 if (error) { 553 /* mbuf is already reclaimed in ipsec4_output. */ 554 m0 = NULL; 555 switch (error) { 556 case EHOSTUNREACH: 557 case ENETUNREACH: 558 case EMSGSIZE: 559 case ENOBUFS: 560 case ENOMEM: 561 break; 562 default: 563 printf("ip4_output (ipsec): error code %d\n", error); 564 /*fall through*/ 565 case ENOENT: 566 /* don't show these error codes to the user */ 567 error = 0; 568 break; 569 } 570 goto bad; 571 } 572 573 /* be sure to update variables that are affected by ipsec4_output() */ 574 ip = mtod(m, struct ip *); 575 hlen = ip->ip_hl << 2; 576 ip_len = ntohs(ip->ip_len); 577 578 if (ro->ro_rt == NULL) { 579 if ((flags & IP_ROUTETOIF) == 0) { 580 printf("ip_output: " 581 "can't update route after IPsec processing\n"); 582 error = EHOSTUNREACH; /*XXX*/ 583 goto bad; 584 } 585 } else { 586 /* nobody uses ia beyond here */ 587 if (state.encap) { 588 ifp = ro->ro_rt->rt_ifp; 589 if ((mtu = ro->ro_rt->rt_rmx.rmx_mtu) == 0) 590 mtu = ifp->if_mtu; 591 } 592 } 593 } 594 skip_ipsec: 595 #endif /*IPSEC*/ 596 #ifdef FAST_IPSEC 597 /* 598 * Check the security policy (SP) for the packet and, if 599 * required, do IPsec-related processing. There are two 600 * cases here; the first time a packet is sent through 601 * it will be untagged and handled by ipsec4_checkpolicy. 602 * If the packet is resubmitted to ip_output (e.g. after 603 * AH, ESP, etc. processing), there will be a tag to bypass 604 * the lookup and related policy checking. 605 */ 606 mtag = m_tag_find(m, PACKET_TAG_IPSEC_PENDING_TDB, NULL); 607 s = splsoftnet(); 608 if (mtag != NULL) { 609 tdbi = (struct tdb_ident *)(mtag + 1); 610 sp = ipsec_getpolicy(tdbi, IPSEC_DIR_OUTBOUND); 611 if (sp == NULL) 612 error = -EINVAL; /* force silent drop */ 613 m_tag_delete(m, mtag); 614 } else { 615 if (inp != NULL && 616 IPSEC_PCB_SKIP_IPSEC(inp->inp_sp, IPSEC_DIR_OUTBOUND)) 617 goto spd_done; 618 sp = ipsec4_checkpolicy(m, IPSEC_DIR_OUTBOUND, flags, 619 &error, inp); 620 } 621 /* 622 * There are four return cases: 623 * sp != NULL apply IPsec policy 624 * sp == NULL, error == 0 no IPsec handling needed 625 * sp == NULL, error == -EINVAL discard packet w/o error 626 * sp == NULL, error != 0 discard packet, report error 627 */ 628 if (sp != NULL) { 629 /* Loop detection, check if ipsec processing already done */ 630 IPSEC_ASSERT(sp->req != NULL, ("ip_output: no ipsec request")); 631 for (mtag = m_tag_first(m); mtag != NULL; 632 mtag = m_tag_next(m, mtag)) { 633 #ifdef MTAG_ABI_COMPAT 634 if (mtag->m_tag_cookie != MTAG_ABI_COMPAT) 635 continue; 636 #endif 637 if (mtag->m_tag_id != PACKET_TAG_IPSEC_OUT_DONE && 638 mtag->m_tag_id != PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED) 639 continue; 640 /* 641 * Check if policy has an SA associated with it. 642 * This can happen when an SP has yet to acquire 643 * an SA; e.g. on first reference. If it occurs, 644 * then we let ipsec4_process_packet do its thing. 645 */ 646 if (sp->req->sav == NULL) 647 break; 648 tdbi = (struct tdb_ident *)(mtag + 1); 649 if (tdbi->spi == sp->req->sav->spi && 650 tdbi->proto == sp->req->sav->sah->saidx.proto && 651 bcmp(&tdbi->dst, &sp->req->sav->sah->saidx.dst, 652 sizeof (union sockaddr_union)) == 0) { 653 /* 654 * No IPsec processing is needed, free 655 * reference to SP. 656 * 657 * NB: null pointer to avoid free at 658 * done: below. 659 */ 660 KEY_FREESP(&sp), sp = NULL; 661 splx(s); 662 goto spd_done; 663 } 664 } 665 666 /* 667 * Do delayed checksums now because we send before 668 * this is done in the normal processing path. 669 */ 670 if (m->m_pkthdr.csum_flags & (M_CSUM_TCPv4|M_CSUM_UDPv4)) { 671 in_delayed_cksum(m); 672 m->m_pkthdr.csum_flags &= ~(M_CSUM_TCPv4|M_CSUM_UDPv4); 673 } 674 675 #ifdef __FreeBSD__ 676 ip->ip_len = htons(ip->ip_len); 677 ip->ip_off = htons(ip->ip_off); 678 #endif 679 680 /* NB: callee frees mbuf */ 681 error = ipsec4_process_packet(m, sp->req, flags, 0); 682 /* 683 * Preserve KAME behaviour: ENOENT can be returned 684 * when an SA acquire is in progress. Don't propagate 685 * this to user-level; it confuses applications. 686 * 687 * XXX this will go away when the SADB is redone. 688 */ 689 if (error == ENOENT) 690 error = 0; 691 splx(s); 692 goto done; 693 } else { 694 splx(s); 695 696 if (error != 0) { 697 /* 698 * Hack: -EINVAL is used to signal that a packet 699 * should be silently discarded. This is typically 700 * because we asked key management for an SA and 701 * it was delayed (e.g. kicked up to IKE). 702 */ 703 if (error == -EINVAL) 704 error = 0; 705 goto bad; 706 } else { 707 /* No IPsec processing for this packet. */ 708 } 709 #ifdef notyet 710 /* 711 * If deferred crypto processing is needed, check that 712 * the interface supports it. 713 */ 714 mtag = m_tag_find(m, PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED, NULL); 715 if (mtag != NULL && (ifp->if_capenable & IFCAP_IPSEC) == 0) { 716 /* notify IPsec to do its own crypto */ 717 ipsp_skipcrypto_unmark((struct tdb_ident *)(mtag + 1)); 718 error = EHOSTUNREACH; 719 goto bad; 720 } 721 #endif 722 } 723 spd_done: 724 #endif /* FAST_IPSEC */ 725 726 #ifdef PFIL_HOOKS 727 /* 728 * Run through list of hooks for output packets. 729 */ 730 if ((error = pfil_run_hooks(&inet_pfil_hook, &m, ifp, PFIL_OUT)) != 0) 731 goto done; 732 if (m == NULL) 733 goto done; 734 735 ip = mtod(m, struct ip *); 736 hlen = ip->ip_hl << 2; 737 #endif /* PFIL_HOOKS */ 738 739 #if IFA_STATS 740 /* 741 * search for the source address structure to 742 * maintain output statistics. 743 */ 744 INADDR_TO_IA(ip->ip_src, ia); 745 #endif 746 747 /* Maybe skip checksums on loopback interfaces. */ 748 if (__predict_true(!(ifp->if_flags & IFF_LOOPBACK) || 749 ip_do_loopback_cksum)) 750 m->m_pkthdr.csum_flags |= M_CSUM_IPv4; 751 sw_csum = m->m_pkthdr.csum_flags & ~ifp->if_csum_flags_tx; 752 /* 753 * If small enough for mtu of path, can just send directly. 754 */ 755 if (ip_len <= mtu) { 756 #if IFA_STATS 757 if (ia) 758 ia->ia_ifa.ifa_data.ifad_outbytes += ip_len; 759 #endif 760 /* 761 * Always initialize the sum to 0! Some HW assisted 762 * checksumming requires this. 763 */ 764 ip->ip_sum = 0; 765 766 /* 767 * Perform any checksums that the hardware can't do 768 * for us. 769 * 770 * XXX Does any hardware require the {th,uh}_sum 771 * XXX fields to be 0? 772 */ 773 if (sw_csum & M_CSUM_IPv4) { 774 ip->ip_sum = in_cksum(m, hlen); 775 m->m_pkthdr.csum_flags &= ~M_CSUM_IPv4; 776 } 777 if (sw_csum & (M_CSUM_TCPv4|M_CSUM_UDPv4)) { 778 in_delayed_cksum(m); 779 m->m_pkthdr.csum_flags &= ~(M_CSUM_TCPv4|M_CSUM_UDPv4); 780 } 781 782 #ifdef IPSEC 783 /* clean ipsec history once it goes out of the node */ 784 ipsec_delaux(m); 785 #endif 786 error = (*ifp->if_output)(ifp, m, sintosa(dst), ro->ro_rt); 787 goto done; 788 } 789 790 /* 791 * We can't use HW checksumming if we're about to 792 * to fragment the packet. 793 * 794 * XXX Some hardware can do this. 795 */ 796 if (m->m_pkthdr.csum_flags & (M_CSUM_TCPv4|M_CSUM_UDPv4)) { 797 in_delayed_cksum(m); 798 m->m_pkthdr.csum_flags &= ~(M_CSUM_TCPv4|M_CSUM_UDPv4); 799 } 800 801 /* 802 * Too large for interface; fragment if possible. 803 * Must be able to put at least 8 bytes per fragment. 804 */ 805 if (ntohs(ip->ip_off) & IP_DF) { 806 if (flags & IP_RETURNMTU) 807 *mtu_p = mtu; 808 error = EMSGSIZE; 809 ipstat.ips_cantfrag++; 810 goto bad; 811 } 812 813 error = ip_fragment(m, ifp, mtu); 814 if (error) { 815 m = NULL; 816 goto bad; 817 } 818 819 for (; m; m = m0) { 820 m0 = m->m_nextpkt; 821 m->m_nextpkt = 0; 822 if (error == 0) { 823 #if IFA_STATS 824 if (ia) 825 ia->ia_ifa.ifa_data.ifad_outbytes += 826 ntohs(ip->ip_len); 827 #endif 828 #ifdef IPSEC 829 /* clean ipsec history once it goes out of the node */ 830 ipsec_delaux(m); 831 #endif 832 KASSERT((m->m_pkthdr.csum_flags & 833 (M_CSUM_UDPv4 | M_CSUM_TCPv4)) == 0); 834 error = (*ifp->if_output)(ifp, m, sintosa(dst), 835 ro->ro_rt); 836 } else 837 m_freem(m); 838 } 839 840 if (error == 0) 841 ipstat.ips_fragmented++; 842 done: 843 if (ro == &iproute && (flags & IP_ROUTETOIF) == 0 && ro->ro_rt) { 844 RTFREE(ro->ro_rt); 845 ro->ro_rt = 0; 846 } 847 848 #ifdef IPSEC 849 if (sp != NULL) { 850 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 851 printf("DP ip_output call free SP:%p\n", sp)); 852 key_freesp(sp); 853 } 854 #endif /* IPSEC */ 855 #ifdef FAST_IPSEC 856 if (sp != NULL) 857 KEY_FREESP(&sp); 858 #endif /* FAST_IPSEC */ 859 860 return (error); 861 bad: 862 m_freem(m); 863 goto done; 864 } 865 866 int 867 ip_fragment(struct mbuf *m, struct ifnet *ifp, u_long mtu) 868 { 869 struct ip *ip, *mhip; 870 struct mbuf *m0; 871 int len, hlen, off; 872 int mhlen, firstlen; 873 struct mbuf **mnext; 874 int sw_csum = m->m_pkthdr.csum_flags; 875 int fragments = 0; 876 int s; 877 int error = 0; 878 879 ip = mtod(m, struct ip *); 880 hlen = ip->ip_hl << 2; 881 if (ifp != NULL) 882 sw_csum &= ~ifp->if_csum_flags_tx; 883 884 len = (mtu - hlen) &~ 7; 885 if (len < 8) { 886 m_freem(m); 887 return (EMSGSIZE); 888 } 889 890 firstlen = len; 891 mnext = &m->m_nextpkt; 892 893 /* 894 * Loop through length of segment after first fragment, 895 * make new header and copy data of each part and link onto chain. 896 */ 897 m0 = m; 898 mhlen = sizeof (struct ip); 899 for (off = hlen + len; off < ntohs(ip->ip_len); off += len) { 900 MGETHDR(m, M_DONTWAIT, MT_HEADER); 901 if (m == 0) { 902 error = ENOBUFS; 903 ipstat.ips_odropped++; 904 goto sendorfree; 905 } 906 MCLAIM(m, m0->m_owner); 907 *mnext = m; 908 mnext = &m->m_nextpkt; 909 m->m_data += max_linkhdr; 910 mhip = mtod(m, struct ip *); 911 *mhip = *ip; 912 /* we must inherit MCAST and BCAST flags */ 913 m->m_flags |= m0->m_flags & (M_MCAST|M_BCAST); 914 if (hlen > sizeof (struct ip)) { 915 mhlen = ip_optcopy(ip, mhip) + sizeof (struct ip); 916 mhip->ip_hl = mhlen >> 2; 917 } 918 m->m_len = mhlen; 919 mhip->ip_off = ((off - hlen) >> 3) + 920 (ntohs(ip->ip_off) & ~IP_MF); 921 if (ip->ip_off & htons(IP_MF)) 922 mhip->ip_off |= IP_MF; 923 if (off + len >= ntohs(ip->ip_len)) 924 len = ntohs(ip->ip_len) - off; 925 else 926 mhip->ip_off |= IP_MF; 927 HTONS(mhip->ip_off); 928 mhip->ip_len = htons((u_int16_t)(len + mhlen)); 929 m->m_next = m_copy(m0, off, len); 930 if (m->m_next == 0) { 931 error = ENOBUFS; /* ??? */ 932 ipstat.ips_odropped++; 933 goto sendorfree; 934 } 935 m->m_pkthdr.len = mhlen + len; 936 m->m_pkthdr.rcvif = (struct ifnet *)0; 937 mhip->ip_sum = 0; 938 if (sw_csum & M_CSUM_IPv4) { 939 mhip->ip_sum = in_cksum(m, mhlen); 940 KASSERT((m->m_pkthdr.csum_flags & M_CSUM_IPv4) == 0); 941 } else { 942 m->m_pkthdr.csum_flags |= M_CSUM_IPv4; 943 } 944 ipstat.ips_ofragments++; 945 fragments++; 946 } 947 /* 948 * Update first fragment by trimming what's been copied out 949 * and updating header, then send each fragment (in order). 950 */ 951 m = m0; 952 m_adj(m, hlen + firstlen - ntohs(ip->ip_len)); 953 m->m_pkthdr.len = hlen + firstlen; 954 ip->ip_len = htons((u_int16_t)m->m_pkthdr.len); 955 ip->ip_off |= htons(IP_MF); 956 ip->ip_sum = 0; 957 if (sw_csum & M_CSUM_IPv4) { 958 ip->ip_sum = in_cksum(m, hlen); 959 m->m_pkthdr.csum_flags &= ~M_CSUM_IPv4; 960 } else { 961 KASSERT(m->m_pkthdr.csum_flags & M_CSUM_IPv4); 962 } 963 sendorfree: 964 /* 965 * If there is no room for all the fragments, don't queue 966 * any of them. 967 */ 968 if (ifp != NULL) { 969 s = splnet(); 970 if (ifp->if_snd.ifq_maxlen - ifp->if_snd.ifq_len < fragments && 971 error == 0) { 972 error = ENOBUFS; 973 ipstat.ips_odropped++; 974 IFQ_INC_DROPS(&ifp->if_snd); 975 } 976 splx(s); 977 } 978 if (error) { 979 for (m = m0; m; m = m0) { 980 m0 = m->m_nextpkt; 981 m->m_nextpkt = NULL; 982 m_freem(m); 983 } 984 } 985 return (error); 986 } 987 988 /* 989 * Process a delayed payload checksum calculation. 990 */ 991 void 992 in_delayed_cksum(struct mbuf *m) 993 { 994 struct ip *ip; 995 u_int16_t csum, offset; 996 997 ip = mtod(m, struct ip *); 998 offset = ip->ip_hl << 2; 999 csum = in4_cksum(m, 0, offset, ntohs(ip->ip_len) - offset); 1000 if (csum == 0 && (m->m_pkthdr.csum_flags & M_CSUM_UDPv4) != 0) 1001 csum = 0xffff; 1002 1003 offset += m->m_pkthdr.csum_data; /* checksum offset */ 1004 1005 if ((offset + sizeof(u_int16_t)) > m->m_len) { 1006 /* This happen when ip options were inserted 1007 printf("in_delayed_cksum: pullup len %d off %d proto %d\n", 1008 m->m_len, offset, ip->ip_p); 1009 */ 1010 m_copyback(m, offset, sizeof(csum), (caddr_t) &csum); 1011 } else 1012 *(u_int16_t *)(mtod(m, caddr_t) + offset) = csum; 1013 } 1014 1015 /* 1016 * Determine the maximum length of the options to be inserted; 1017 * we would far rather allocate too much space rather than too little. 1018 */ 1019 1020 u_int 1021 ip_optlen(struct inpcb *inp) 1022 { 1023 struct mbuf *m = inp->inp_options; 1024 1025 if (m && m->m_len > offsetof(struct ipoption, ipopt_dst)) 1026 return (m->m_len - offsetof(struct ipoption, ipopt_dst)); 1027 else 1028 return 0; 1029 } 1030 1031 1032 /* 1033 * Insert IP options into preformed packet. 1034 * Adjust IP destination as required for IP source routing, 1035 * as indicated by a non-zero in_addr at the start of the options. 1036 */ 1037 static struct mbuf * 1038 ip_insertoptions(struct mbuf *m, struct mbuf *opt, int *phlen) 1039 { 1040 struct ipoption *p = mtod(opt, struct ipoption *); 1041 struct mbuf *n; 1042 struct ip *ip = mtod(m, struct ip *); 1043 unsigned optlen; 1044 1045 optlen = opt->m_len - sizeof(p->ipopt_dst); 1046 if (optlen + ntohs(ip->ip_len) > IP_MAXPACKET) 1047 return (m); /* XXX should fail */ 1048 if (!in_nullhost(p->ipopt_dst)) 1049 ip->ip_dst = p->ipopt_dst; 1050 if (M_READONLY(m) || M_LEADINGSPACE(m) < optlen) { 1051 MGETHDR(n, M_DONTWAIT, MT_HEADER); 1052 if (n == 0) 1053 return (m); 1054 MCLAIM(n, m->m_owner); 1055 M_COPY_PKTHDR(n, m); 1056 m_tag_delete_chain(m, NULL); 1057 m->m_flags &= ~M_PKTHDR; 1058 m->m_len -= sizeof(struct ip); 1059 m->m_data += sizeof(struct ip); 1060 n->m_next = m; 1061 m = n; 1062 m->m_len = optlen + sizeof(struct ip); 1063 m->m_data += max_linkhdr; 1064 bcopy((caddr_t)ip, mtod(m, caddr_t), sizeof(struct ip)); 1065 } else { 1066 m->m_data -= optlen; 1067 m->m_len += optlen; 1068 memmove(mtod(m, caddr_t), ip, sizeof(struct ip)); 1069 } 1070 m->m_pkthdr.len += optlen; 1071 ip = mtod(m, struct ip *); 1072 bcopy((caddr_t)p->ipopt_list, (caddr_t)(ip + 1), (unsigned)optlen); 1073 *phlen = sizeof(struct ip) + optlen; 1074 ip->ip_len = htons(ntohs(ip->ip_len) + optlen); 1075 return (m); 1076 } 1077 1078 /* 1079 * Copy options from ip to jp, 1080 * omitting those not copied during fragmentation. 1081 */ 1082 int 1083 ip_optcopy(struct ip *ip, struct ip *jp) 1084 { 1085 u_char *cp, *dp; 1086 int opt, optlen, cnt; 1087 1088 cp = (u_char *)(ip + 1); 1089 dp = (u_char *)(jp + 1); 1090 cnt = (ip->ip_hl << 2) - sizeof (struct ip); 1091 for (; cnt > 0; cnt -= optlen, cp += optlen) { 1092 opt = cp[0]; 1093 if (opt == IPOPT_EOL) 1094 break; 1095 if (opt == IPOPT_NOP) { 1096 /* Preserve for IP mcast tunnel's LSRR alignment. */ 1097 *dp++ = IPOPT_NOP; 1098 optlen = 1; 1099 continue; 1100 } 1101 #ifdef DIAGNOSTIC 1102 if (cnt < IPOPT_OLEN + sizeof(*cp)) 1103 panic("malformed IPv4 option passed to ip_optcopy"); 1104 #endif 1105 optlen = cp[IPOPT_OLEN]; 1106 #ifdef DIAGNOSTIC 1107 if (optlen < IPOPT_OLEN + sizeof(*cp) || optlen > cnt) 1108 panic("malformed IPv4 option passed to ip_optcopy"); 1109 #endif 1110 /* bogus lengths should have been caught by ip_dooptions */ 1111 if (optlen > cnt) 1112 optlen = cnt; 1113 if (IPOPT_COPIED(opt)) { 1114 bcopy((caddr_t)cp, (caddr_t)dp, (unsigned)optlen); 1115 dp += optlen; 1116 } 1117 } 1118 for (optlen = dp - (u_char *)(jp+1); optlen & 0x3; optlen++) 1119 *dp++ = IPOPT_EOL; 1120 return (optlen); 1121 } 1122 1123 /* 1124 * IP socket option processing. 1125 */ 1126 int 1127 ip_ctloutput(int op, struct socket *so, int level, int optname, 1128 struct mbuf **mp) 1129 { 1130 struct inpcb *inp = sotoinpcb(so); 1131 struct mbuf *m = *mp; 1132 int optval = 0; 1133 int error = 0; 1134 #if defined(IPSEC) || defined(FAST_IPSEC) 1135 struct proc *p = curproc; /*XXX*/ 1136 #endif 1137 1138 if (level != IPPROTO_IP) { 1139 error = EINVAL; 1140 if (op == PRCO_SETOPT && *mp) 1141 (void) m_free(*mp); 1142 } else switch (op) { 1143 1144 case PRCO_SETOPT: 1145 switch (optname) { 1146 case IP_OPTIONS: 1147 #ifdef notyet 1148 case IP_RETOPTS: 1149 return (ip_pcbopts(optname, &inp->inp_options, m)); 1150 #else 1151 return (ip_pcbopts(&inp->inp_options, m)); 1152 #endif 1153 1154 case IP_TOS: 1155 case IP_TTL: 1156 case IP_RECVOPTS: 1157 case IP_RECVRETOPTS: 1158 case IP_RECVDSTADDR: 1159 case IP_RECVIF: 1160 if (m == NULL || m->m_len != sizeof(int)) 1161 error = EINVAL; 1162 else { 1163 optval = *mtod(m, int *); 1164 switch (optname) { 1165 1166 case IP_TOS: 1167 inp->inp_ip.ip_tos = optval; 1168 break; 1169 1170 case IP_TTL: 1171 inp->inp_ip.ip_ttl = optval; 1172 break; 1173 #define OPTSET(bit) \ 1174 if (optval) \ 1175 inp->inp_flags |= bit; \ 1176 else \ 1177 inp->inp_flags &= ~bit; 1178 1179 case IP_RECVOPTS: 1180 OPTSET(INP_RECVOPTS); 1181 break; 1182 1183 case IP_RECVRETOPTS: 1184 OPTSET(INP_RECVRETOPTS); 1185 break; 1186 1187 case IP_RECVDSTADDR: 1188 OPTSET(INP_RECVDSTADDR); 1189 break; 1190 1191 case IP_RECVIF: 1192 OPTSET(INP_RECVIF); 1193 break; 1194 } 1195 } 1196 break; 1197 #undef OPTSET 1198 1199 case IP_MULTICAST_IF: 1200 case IP_MULTICAST_TTL: 1201 case IP_MULTICAST_LOOP: 1202 case IP_ADD_MEMBERSHIP: 1203 case IP_DROP_MEMBERSHIP: 1204 error = ip_setmoptions(optname, &inp->inp_moptions, m); 1205 break; 1206 1207 case IP_PORTRANGE: 1208 if (m == 0 || m->m_len != sizeof(int)) 1209 error = EINVAL; 1210 else { 1211 optval = *mtod(m, int *); 1212 1213 switch (optval) { 1214 1215 case IP_PORTRANGE_DEFAULT: 1216 case IP_PORTRANGE_HIGH: 1217 inp->inp_flags &= ~(INP_LOWPORT); 1218 break; 1219 1220 case IP_PORTRANGE_LOW: 1221 inp->inp_flags |= INP_LOWPORT; 1222 break; 1223 1224 default: 1225 error = EINVAL; 1226 break; 1227 } 1228 } 1229 break; 1230 1231 #if defined(IPSEC) || defined(FAST_IPSEC) 1232 case IP_IPSEC_POLICY: 1233 { 1234 caddr_t req = NULL; 1235 size_t len = 0; 1236 int priv = 0; 1237 1238 #ifdef __NetBSD__ 1239 if (p == 0 || suser(p->p_ucred, &p->p_acflag)) 1240 priv = 0; 1241 else 1242 priv = 1; 1243 #else 1244 priv = (in6p->in6p_socket->so_state & SS_PRIV); 1245 #endif 1246 if (m) { 1247 req = mtod(m, caddr_t); 1248 len = m->m_len; 1249 } 1250 error = ipsec4_set_policy(inp, optname, req, len, priv); 1251 break; 1252 } 1253 #endif /*IPSEC*/ 1254 1255 default: 1256 error = ENOPROTOOPT; 1257 break; 1258 } 1259 if (m) 1260 (void)m_free(m); 1261 break; 1262 1263 case PRCO_GETOPT: 1264 switch (optname) { 1265 case IP_OPTIONS: 1266 case IP_RETOPTS: 1267 *mp = m = m_get(M_WAIT, MT_SOOPTS); 1268 MCLAIM(m, so->so_mowner); 1269 if (inp->inp_options) { 1270 m->m_len = inp->inp_options->m_len; 1271 bcopy(mtod(inp->inp_options, caddr_t), 1272 mtod(m, caddr_t), (unsigned)m->m_len); 1273 } else 1274 m->m_len = 0; 1275 break; 1276 1277 case IP_TOS: 1278 case IP_TTL: 1279 case IP_RECVOPTS: 1280 case IP_RECVRETOPTS: 1281 case IP_RECVDSTADDR: 1282 case IP_RECVIF: 1283 case IP_ERRORMTU: 1284 *mp = m = m_get(M_WAIT, MT_SOOPTS); 1285 MCLAIM(m, so->so_mowner); 1286 m->m_len = sizeof(int); 1287 switch (optname) { 1288 1289 case IP_TOS: 1290 optval = inp->inp_ip.ip_tos; 1291 break; 1292 1293 case IP_TTL: 1294 optval = inp->inp_ip.ip_ttl; 1295 break; 1296 1297 case IP_ERRORMTU: 1298 optval = inp->inp_errormtu; 1299 break; 1300 1301 #define OPTBIT(bit) (inp->inp_flags & bit ? 1 : 0) 1302 1303 case IP_RECVOPTS: 1304 optval = OPTBIT(INP_RECVOPTS); 1305 break; 1306 1307 case IP_RECVRETOPTS: 1308 optval = OPTBIT(INP_RECVRETOPTS); 1309 break; 1310 1311 case IP_RECVDSTADDR: 1312 optval = OPTBIT(INP_RECVDSTADDR); 1313 break; 1314 1315 case IP_RECVIF: 1316 optval = OPTBIT(INP_RECVIF); 1317 break; 1318 } 1319 *mtod(m, int *) = optval; 1320 break; 1321 1322 #if 0 /* defined(IPSEC) || defined(FAST_IPSEC) */ 1323 /* XXX: code broken */ 1324 case IP_IPSEC_POLICY: 1325 { 1326 caddr_t req = NULL; 1327 size_t len = 0; 1328 1329 if (m) { 1330 req = mtod(m, caddr_t); 1331 len = m->m_len; 1332 } 1333 error = ipsec4_get_policy(inp, req, len, mp); 1334 break; 1335 } 1336 #endif /*IPSEC*/ 1337 1338 case IP_MULTICAST_IF: 1339 case IP_MULTICAST_TTL: 1340 case IP_MULTICAST_LOOP: 1341 case IP_ADD_MEMBERSHIP: 1342 case IP_DROP_MEMBERSHIP: 1343 error = ip_getmoptions(optname, inp->inp_moptions, mp); 1344 if (*mp) 1345 MCLAIM(*mp, so->so_mowner); 1346 break; 1347 1348 case IP_PORTRANGE: 1349 *mp = m = m_get(M_WAIT, MT_SOOPTS); 1350 MCLAIM(m, so->so_mowner); 1351 m->m_len = sizeof(int); 1352 1353 if (inp->inp_flags & INP_LOWPORT) 1354 optval = IP_PORTRANGE_LOW; 1355 else 1356 optval = IP_PORTRANGE_DEFAULT; 1357 1358 *mtod(m, int *) = optval; 1359 break; 1360 1361 default: 1362 error = ENOPROTOOPT; 1363 break; 1364 } 1365 break; 1366 } 1367 return (error); 1368 } 1369 1370 /* 1371 * Set up IP options in pcb for insertion in output packets. 1372 * Store in mbuf with pointer in pcbopt, adding pseudo-option 1373 * with destination address if source routed. 1374 */ 1375 int 1376 #ifdef notyet 1377 ip_pcbopts(int optname, struct mbuf **pcbopt, struct mbuf *m) 1378 #else 1379 ip_pcbopts(struct mbuf **pcbopt, struct mbuf *m) 1380 #endif 1381 { 1382 int cnt, optlen; 1383 u_char *cp; 1384 u_char opt; 1385 1386 /* turn off any old options */ 1387 if (*pcbopt) 1388 (void)m_free(*pcbopt); 1389 *pcbopt = 0; 1390 if (m == (struct mbuf *)0 || m->m_len == 0) { 1391 /* 1392 * Only turning off any previous options. 1393 */ 1394 if (m) 1395 (void)m_free(m); 1396 return (0); 1397 } 1398 1399 #ifndef __vax__ 1400 if (m->m_len % sizeof(int32_t)) 1401 goto bad; 1402 #endif 1403 /* 1404 * IP first-hop destination address will be stored before 1405 * actual options; move other options back 1406 * and clear it when none present. 1407 */ 1408 if (m->m_data + m->m_len + sizeof(struct in_addr) >= &m->m_dat[MLEN]) 1409 goto bad; 1410 cnt = m->m_len; 1411 m->m_len += sizeof(struct in_addr); 1412 cp = mtod(m, u_char *) + sizeof(struct in_addr); 1413 memmove(cp, mtod(m, caddr_t), (unsigned)cnt); 1414 bzero(mtod(m, caddr_t), sizeof(struct in_addr)); 1415 1416 for (; cnt > 0; cnt -= optlen, cp += optlen) { 1417 opt = cp[IPOPT_OPTVAL]; 1418 if (opt == IPOPT_EOL) 1419 break; 1420 if (opt == IPOPT_NOP) 1421 optlen = 1; 1422 else { 1423 if (cnt < IPOPT_OLEN + sizeof(*cp)) 1424 goto bad; 1425 optlen = cp[IPOPT_OLEN]; 1426 if (optlen < IPOPT_OLEN + sizeof(*cp) || optlen > cnt) 1427 goto bad; 1428 } 1429 switch (opt) { 1430 1431 default: 1432 break; 1433 1434 case IPOPT_LSRR: 1435 case IPOPT_SSRR: 1436 /* 1437 * user process specifies route as: 1438 * ->A->B->C->D 1439 * D must be our final destination (but we can't 1440 * check that since we may not have connected yet). 1441 * A is first hop destination, which doesn't appear in 1442 * actual IP option, but is stored before the options. 1443 */ 1444 if (optlen < IPOPT_MINOFF - 1 + sizeof(struct in_addr)) 1445 goto bad; 1446 m->m_len -= sizeof(struct in_addr); 1447 cnt -= sizeof(struct in_addr); 1448 optlen -= sizeof(struct in_addr); 1449 cp[IPOPT_OLEN] = optlen; 1450 /* 1451 * Move first hop before start of options. 1452 */ 1453 bcopy((caddr_t)&cp[IPOPT_OFFSET+1], mtod(m, caddr_t), 1454 sizeof(struct in_addr)); 1455 /* 1456 * Then copy rest of options back 1457 * to close up the deleted entry. 1458 */ 1459 (void)memmove(&cp[IPOPT_OFFSET+1], 1460 &cp[IPOPT_OFFSET+1] + sizeof(struct in_addr), 1461 (unsigned)cnt - (IPOPT_MINOFF - 1)); 1462 break; 1463 } 1464 } 1465 if (m->m_len > MAX_IPOPTLEN + sizeof(struct in_addr)) 1466 goto bad; 1467 *pcbopt = m; 1468 return (0); 1469 1470 bad: 1471 (void)m_free(m); 1472 return (EINVAL); 1473 } 1474 1475 /* 1476 * following RFC1724 section 3.3, 0.0.0.0/8 is interpreted as interface index. 1477 */ 1478 static struct ifnet * 1479 ip_multicast_if(struct in_addr *a, int *ifindexp) 1480 { 1481 int ifindex; 1482 struct ifnet *ifp = NULL; 1483 struct in_ifaddr *ia; 1484 1485 if (ifindexp) 1486 *ifindexp = 0; 1487 if (ntohl(a->s_addr) >> 24 == 0) { 1488 ifindex = ntohl(a->s_addr) & 0xffffff; 1489 if (ifindex < 0 || if_indexlim <= ifindex) 1490 return NULL; 1491 ifp = ifindex2ifnet[ifindex]; 1492 if (!ifp) 1493 return NULL; 1494 if (ifindexp) 1495 *ifindexp = ifindex; 1496 } else { 1497 LIST_FOREACH(ia, &IN_IFADDR_HASH(a->s_addr), ia_hash) { 1498 if (in_hosteq(ia->ia_addr.sin_addr, *a) && 1499 (ia->ia_ifp->if_flags & IFF_MULTICAST) != 0) { 1500 ifp = ia->ia_ifp; 1501 break; 1502 } 1503 } 1504 } 1505 return ifp; 1506 } 1507 1508 /* 1509 * Set the IP multicast options in response to user setsockopt(). 1510 */ 1511 int 1512 ip_setmoptions(int optname, struct ip_moptions **imop, struct mbuf *m) 1513 { 1514 int error = 0; 1515 u_char loop; 1516 int i; 1517 struct in_addr addr; 1518 struct ip_mreq *mreq; 1519 struct ifnet *ifp; 1520 struct ip_moptions *imo = *imop; 1521 struct route ro; 1522 struct sockaddr_in *dst; 1523 int ifindex; 1524 1525 if (imo == NULL) { 1526 /* 1527 * No multicast option buffer attached to the pcb; 1528 * allocate one and initialize to default values. 1529 */ 1530 imo = (struct ip_moptions *)malloc(sizeof(*imo), M_IPMOPTS, 1531 M_WAITOK); 1532 1533 if (imo == NULL) 1534 return (ENOBUFS); 1535 *imop = imo; 1536 imo->imo_multicast_ifp = NULL; 1537 imo->imo_multicast_addr.s_addr = INADDR_ANY; 1538 imo->imo_multicast_ttl = IP_DEFAULT_MULTICAST_TTL; 1539 imo->imo_multicast_loop = IP_DEFAULT_MULTICAST_LOOP; 1540 imo->imo_num_memberships = 0; 1541 } 1542 1543 switch (optname) { 1544 1545 case IP_MULTICAST_IF: 1546 /* 1547 * Select the interface for outgoing multicast packets. 1548 */ 1549 if (m == NULL || m->m_len != sizeof(struct in_addr)) { 1550 error = EINVAL; 1551 break; 1552 } 1553 addr = *(mtod(m, struct in_addr *)); 1554 /* 1555 * INADDR_ANY is used to remove a previous selection. 1556 * When no interface is selected, a default one is 1557 * chosen every time a multicast packet is sent. 1558 */ 1559 if (in_nullhost(addr)) { 1560 imo->imo_multicast_ifp = NULL; 1561 break; 1562 } 1563 /* 1564 * The selected interface is identified by its local 1565 * IP address. Find the interface and confirm that 1566 * it supports multicasting. 1567 */ 1568 ifp = ip_multicast_if(&addr, &ifindex); 1569 if (ifp == NULL || (ifp->if_flags & IFF_MULTICAST) == 0) { 1570 error = EADDRNOTAVAIL; 1571 break; 1572 } 1573 imo->imo_multicast_ifp = ifp; 1574 if (ifindex) 1575 imo->imo_multicast_addr = addr; 1576 else 1577 imo->imo_multicast_addr.s_addr = INADDR_ANY; 1578 break; 1579 1580 case IP_MULTICAST_TTL: 1581 /* 1582 * Set the IP time-to-live for outgoing multicast packets. 1583 */ 1584 if (m == NULL || m->m_len != 1) { 1585 error = EINVAL; 1586 break; 1587 } 1588 imo->imo_multicast_ttl = *(mtod(m, u_char *)); 1589 break; 1590 1591 case IP_MULTICAST_LOOP: 1592 /* 1593 * Set the loopback flag for outgoing multicast packets. 1594 * Must be zero or one. 1595 */ 1596 if (m == NULL || m->m_len != 1 || 1597 (loop = *(mtod(m, u_char *))) > 1) { 1598 error = EINVAL; 1599 break; 1600 } 1601 imo->imo_multicast_loop = loop; 1602 break; 1603 1604 case IP_ADD_MEMBERSHIP: 1605 /* 1606 * Add a multicast group membership. 1607 * Group must be a valid IP multicast address. 1608 */ 1609 if (m == NULL || m->m_len != sizeof(struct ip_mreq)) { 1610 error = EINVAL; 1611 break; 1612 } 1613 mreq = mtod(m, struct ip_mreq *); 1614 if (!IN_MULTICAST(mreq->imr_multiaddr.s_addr)) { 1615 error = EINVAL; 1616 break; 1617 } 1618 /* 1619 * If no interface address was provided, use the interface of 1620 * the route to the given multicast address. 1621 */ 1622 if (in_nullhost(mreq->imr_interface)) { 1623 bzero((caddr_t)&ro, sizeof(ro)); 1624 ro.ro_rt = NULL; 1625 dst = satosin(&ro.ro_dst); 1626 dst->sin_len = sizeof(*dst); 1627 dst->sin_family = AF_INET; 1628 dst->sin_addr = mreq->imr_multiaddr; 1629 rtalloc(&ro); 1630 if (ro.ro_rt == NULL) { 1631 error = EADDRNOTAVAIL; 1632 break; 1633 } 1634 ifp = ro.ro_rt->rt_ifp; 1635 rtfree(ro.ro_rt); 1636 } else { 1637 ifp = ip_multicast_if(&mreq->imr_interface, NULL); 1638 } 1639 /* 1640 * See if we found an interface, and confirm that it 1641 * supports multicast. 1642 */ 1643 if (ifp == NULL || (ifp->if_flags & IFF_MULTICAST) == 0) { 1644 error = EADDRNOTAVAIL; 1645 break; 1646 } 1647 /* 1648 * See if the membership already exists or if all the 1649 * membership slots are full. 1650 */ 1651 for (i = 0; i < imo->imo_num_memberships; ++i) { 1652 if (imo->imo_membership[i]->inm_ifp == ifp && 1653 in_hosteq(imo->imo_membership[i]->inm_addr, 1654 mreq->imr_multiaddr)) 1655 break; 1656 } 1657 if (i < imo->imo_num_memberships) { 1658 error = EADDRINUSE; 1659 break; 1660 } 1661 if (i == IP_MAX_MEMBERSHIPS) { 1662 error = ETOOMANYREFS; 1663 break; 1664 } 1665 /* 1666 * Everything looks good; add a new record to the multicast 1667 * address list for the given interface. 1668 */ 1669 if ((imo->imo_membership[i] = 1670 in_addmulti(&mreq->imr_multiaddr, ifp)) == NULL) { 1671 error = ENOBUFS; 1672 break; 1673 } 1674 ++imo->imo_num_memberships; 1675 break; 1676 1677 case IP_DROP_MEMBERSHIP: 1678 /* 1679 * Drop a multicast group membership. 1680 * Group must be a valid IP multicast address. 1681 */ 1682 if (m == NULL || m->m_len != sizeof(struct ip_mreq)) { 1683 error = EINVAL; 1684 break; 1685 } 1686 mreq = mtod(m, struct ip_mreq *); 1687 if (!IN_MULTICAST(mreq->imr_multiaddr.s_addr)) { 1688 error = EINVAL; 1689 break; 1690 } 1691 /* 1692 * If an interface address was specified, get a pointer 1693 * to its ifnet structure. 1694 */ 1695 if (in_nullhost(mreq->imr_interface)) 1696 ifp = NULL; 1697 else { 1698 ifp = ip_multicast_if(&mreq->imr_interface, NULL); 1699 if (ifp == NULL) { 1700 error = EADDRNOTAVAIL; 1701 break; 1702 } 1703 } 1704 /* 1705 * Find the membership in the membership array. 1706 */ 1707 for (i = 0; i < imo->imo_num_memberships; ++i) { 1708 if ((ifp == NULL || 1709 imo->imo_membership[i]->inm_ifp == ifp) && 1710 in_hosteq(imo->imo_membership[i]->inm_addr, 1711 mreq->imr_multiaddr)) 1712 break; 1713 } 1714 if (i == imo->imo_num_memberships) { 1715 error = EADDRNOTAVAIL; 1716 break; 1717 } 1718 /* 1719 * Give up the multicast address record to which the 1720 * membership points. 1721 */ 1722 in_delmulti(imo->imo_membership[i]); 1723 /* 1724 * Remove the gap in the membership array. 1725 */ 1726 for (++i; i < imo->imo_num_memberships; ++i) 1727 imo->imo_membership[i-1] = imo->imo_membership[i]; 1728 --imo->imo_num_memberships; 1729 break; 1730 1731 default: 1732 error = EOPNOTSUPP; 1733 break; 1734 } 1735 1736 /* 1737 * If all options have default values, no need to keep the mbuf. 1738 */ 1739 if (imo->imo_multicast_ifp == NULL && 1740 imo->imo_multicast_ttl == IP_DEFAULT_MULTICAST_TTL && 1741 imo->imo_multicast_loop == IP_DEFAULT_MULTICAST_LOOP && 1742 imo->imo_num_memberships == 0) { 1743 free(*imop, M_IPMOPTS); 1744 *imop = NULL; 1745 } 1746 1747 return (error); 1748 } 1749 1750 /* 1751 * Return the IP multicast options in response to user getsockopt(). 1752 */ 1753 int 1754 ip_getmoptions(int optname, struct ip_moptions *imo, struct mbuf **mp) 1755 { 1756 u_char *ttl; 1757 u_char *loop; 1758 struct in_addr *addr; 1759 struct in_ifaddr *ia; 1760 1761 *mp = m_get(M_WAIT, MT_SOOPTS); 1762 1763 switch (optname) { 1764 1765 case IP_MULTICAST_IF: 1766 addr = mtod(*mp, struct in_addr *); 1767 (*mp)->m_len = sizeof(struct in_addr); 1768 if (imo == NULL || imo->imo_multicast_ifp == NULL) 1769 *addr = zeroin_addr; 1770 else if (imo->imo_multicast_addr.s_addr) { 1771 /* return the value user has set */ 1772 *addr = imo->imo_multicast_addr; 1773 } else { 1774 IFP_TO_IA(imo->imo_multicast_ifp, ia); 1775 *addr = ia ? ia->ia_addr.sin_addr : zeroin_addr; 1776 } 1777 return (0); 1778 1779 case IP_MULTICAST_TTL: 1780 ttl = mtod(*mp, u_char *); 1781 (*mp)->m_len = 1; 1782 *ttl = imo ? imo->imo_multicast_ttl 1783 : IP_DEFAULT_MULTICAST_TTL; 1784 return (0); 1785 1786 case IP_MULTICAST_LOOP: 1787 loop = mtod(*mp, u_char *); 1788 (*mp)->m_len = 1; 1789 *loop = imo ? imo->imo_multicast_loop 1790 : IP_DEFAULT_MULTICAST_LOOP; 1791 return (0); 1792 1793 default: 1794 return (EOPNOTSUPP); 1795 } 1796 } 1797 1798 /* 1799 * Discard the IP multicast options. 1800 */ 1801 void 1802 ip_freemoptions(struct ip_moptions *imo) 1803 { 1804 int i; 1805 1806 if (imo != NULL) { 1807 for (i = 0; i < imo->imo_num_memberships; ++i) 1808 in_delmulti(imo->imo_membership[i]); 1809 free(imo, M_IPMOPTS); 1810 } 1811 } 1812 1813 /* 1814 * Routine called from ip_output() to loop back a copy of an IP multicast 1815 * packet to the input queue of a specified interface. Note that this 1816 * calls the output routine of the loopback "driver", but with an interface 1817 * pointer that might NOT be lo0ifp -- easier than replicating that code here. 1818 */ 1819 static void 1820 ip_mloopback(struct ifnet *ifp, struct mbuf *m, struct sockaddr_in *dst) 1821 { 1822 struct ip *ip; 1823 struct mbuf *copym; 1824 1825 copym = m_copy(m, 0, M_COPYALL); 1826 if (copym != NULL 1827 && (copym->m_flags & M_EXT || copym->m_len < sizeof(struct ip))) 1828 copym = m_pullup(copym, sizeof(struct ip)); 1829 if (copym != NULL) { 1830 /* 1831 * We don't bother to fragment if the IP length is greater 1832 * than the interface's MTU. Can this possibly matter? 1833 */ 1834 ip = mtod(copym, struct ip *); 1835 1836 if (copym->m_pkthdr.csum_flags & (M_CSUM_TCPv4|M_CSUM_UDPv4)) { 1837 in_delayed_cksum(copym); 1838 copym->m_pkthdr.csum_flags &= 1839 ~(M_CSUM_TCPv4|M_CSUM_UDPv4); 1840 } 1841 1842 ip->ip_sum = 0; 1843 ip->ip_sum = in_cksum(copym, ip->ip_hl << 2); 1844 (void) looutput(ifp, copym, sintosa(dst), NULL); 1845 } 1846 } 1847