1 /* $NetBSD: ip_output.c,v 1.129 2003/12/10 11:46:33 itojun 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 1.129 2003/12/10 11:46:33 itojun 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 __P((struct mbuf *, struct mbuf *, int *)); 151 static struct ifnet *ip_multicast_if __P((struct in_addr *, int *)); 152 static void ip_mloopback 153 __P((struct ifnet *, struct mbuf *, struct sockaddr_in *)); 154 155 #ifdef PFIL_HOOKS 156 extern struct pfil_head inet_pfil_hook; /* XXX */ 157 #endif 158 159 /* 160 * IP output. The packet in mbuf chain m contains a skeletal IP 161 * header (with len, off, ttl, proto, tos, src, dst). 162 * The mbuf chain containing the packet will be freed. 163 * The mbuf opt, if present, will not be freed. 164 */ 165 int 166 #if __STDC__ 167 ip_output(struct mbuf *m0, ...) 168 #else 169 ip_output(m0, va_alist) 170 struct mbuf *m0; 171 va_dcl 172 #endif 173 { 174 struct ip *ip; 175 struct ifnet *ifp; 176 struct mbuf *m = m0; 177 int hlen = sizeof (struct ip); 178 int len, error = 0; 179 struct route iproute; 180 struct sockaddr_in *dst; 181 struct in_ifaddr *ia; 182 struct mbuf *opt; 183 struct route *ro; 184 int flags, sw_csum; 185 int *mtu_p; 186 u_long mtu; 187 struct ip_moptions *imo; 188 struct socket *so; 189 va_list ap; 190 #ifdef IPSEC 191 struct secpolicy *sp = NULL; 192 #endif /*IPSEC*/ 193 #ifdef FAST_IPSEC 194 struct inpcb *inp; 195 struct m_tag *mtag; 196 struct secpolicy *sp = NULL; 197 struct tdb_ident *tdbi; 198 int s; 199 #endif 200 u_int16_t ip_len; 201 202 len = 0; 203 va_start(ap, m0); 204 opt = va_arg(ap, struct mbuf *); 205 ro = va_arg(ap, struct route *); 206 flags = va_arg(ap, int); 207 imo = va_arg(ap, struct ip_moptions *); 208 so = va_arg(ap, struct socket *); 209 if (flags & IP_RETURNMTU) 210 mtu_p = va_arg(ap, int *); 211 else 212 mtu_p = NULL; 213 va_end(ap); 214 215 MCLAIM(m, &ip_tx_mowner); 216 #ifdef FAST_IPSEC 217 if (so != NULL && so->so_proto->pr_domain->dom_family == AF_INET) 218 inp = (struct inpcb *)so->so_pcb; 219 else 220 inp = NULL; 221 #endif /*IPSEC*/ 222 223 #ifdef DIAGNOSTIC 224 if ((m->m_flags & M_PKTHDR) == 0) 225 panic("ip_output no HDR"); 226 #endif 227 if (opt) { 228 m = ip_insertoptions(m, opt, &len); 229 if (len >= sizeof(struct ip)) 230 hlen = len; 231 } 232 ip = mtod(m, struct ip *); 233 /* 234 * Fill in IP header. 235 */ 236 if ((flags & (IP_FORWARDING|IP_RAWOUTPUT)) == 0) { 237 ip->ip_v = IPVERSION; 238 ip->ip_off = htons(0); 239 ip->ip_id = ip_newid(); 240 ip->ip_hl = hlen >> 2; 241 ipstat.ips_localout++; 242 } else { 243 hlen = ip->ip_hl << 2; 244 } 245 /* 246 * Route packet. 247 */ 248 if (ro == 0) { 249 ro = &iproute; 250 bzero((caddr_t)ro, sizeof (*ro)); 251 } 252 dst = satosin(&ro->ro_dst); 253 /* 254 * If there is a cached route, 255 * check that it is to the same destination 256 * and is still up. If not, free it and try again. 257 * The address family should also be checked in case of sharing the 258 * cache with IPv6. 259 */ 260 if (ro->ro_rt && ((ro->ro_rt->rt_flags & RTF_UP) == 0 || 261 dst->sin_family != AF_INET || 262 !in_hosteq(dst->sin_addr, ip->ip_dst))) { 263 RTFREE(ro->ro_rt); 264 ro->ro_rt = (struct rtentry *)0; 265 } 266 if (ro->ro_rt == 0) { 267 bzero(dst, sizeof(*dst)); 268 dst->sin_family = AF_INET; 269 dst->sin_len = sizeof(*dst); 270 dst->sin_addr = ip->ip_dst; 271 } 272 /* 273 * If routing to interface only, 274 * short circuit routing lookup. 275 */ 276 if (flags & IP_ROUTETOIF) { 277 if ((ia = ifatoia(ifa_ifwithladdr(sintosa(dst)))) == 0) { 278 ipstat.ips_noroute++; 279 error = ENETUNREACH; 280 goto bad; 281 } 282 ifp = ia->ia_ifp; 283 mtu = ifp->if_mtu; 284 ip->ip_ttl = 1; 285 } else if ((IN_MULTICAST(ip->ip_dst.s_addr) || 286 ip->ip_dst.s_addr == INADDR_BROADCAST) && 287 imo != NULL && imo->imo_multicast_ifp != NULL) { 288 ifp = imo->imo_multicast_ifp; 289 mtu = ifp->if_mtu; 290 IFP_TO_IA(ifp, ia); 291 } else { 292 if (ro->ro_rt == 0) 293 rtalloc(ro); 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 if ((mtu = ro->ro_rt->rt_rmx.rmx_mtu) == 0) 302 mtu = ifp->if_mtu; 303 ro->ro_rt->rt_use++; 304 if (ro->ro_rt->rt_flags & RTF_GATEWAY) 305 dst = satosin(ro->ro_rt->rt_gateway); 306 } 307 if (IN_MULTICAST(ip->ip_dst.s_addr) || 308 (ip->ip_dst.s_addr == INADDR_BROADCAST)) { 309 struct in_multi *inm; 310 311 m->m_flags |= (ip->ip_dst.s_addr == INADDR_BROADCAST) ? 312 M_BCAST : 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 = satosin(&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 else 325 ip->ip_ttl = IP_DEFAULT_MULTICAST_TTL; 326 327 /* 328 * if we don't know the outgoing ifp yet, we can't generate 329 * output 330 */ 331 if (!ifp) { 332 ipstat.ips_noroute++; 333 error = ENETUNREACH; 334 goto bad; 335 } 336 337 /* 338 * If the packet is multicast or broadcast, confirm that 339 * the outgoing interface can transmit it. 340 */ 341 if (((m->m_flags & M_MCAST) && 342 (ifp->if_flags & IFF_MULTICAST) == 0) || 343 ((m->m_flags & M_BCAST) && 344 (ifp->if_flags & (IFF_BROADCAST|IFF_POINTOPOINT)) == 0)) { 345 ipstat.ips_noroute++; 346 error = ENETUNREACH; 347 goto bad; 348 } 349 /* 350 * If source address not specified yet, use an address 351 * of outgoing interface. 352 */ 353 if (in_nullhost(ip->ip_src)) { 354 struct in_ifaddr *ia; 355 356 IFP_TO_IA(ifp, ia); 357 if (!ia) { 358 error = EADDRNOTAVAIL; 359 goto bad; 360 } 361 ip->ip_src = ia->ia_addr.sin_addr; 362 } 363 364 IN_LOOKUP_MULTI(ip->ip_dst, ifp, inm); 365 if (inm != NULL && 366 (imo == NULL || imo->imo_multicast_loop)) { 367 /* 368 * If we belong to the destination multicast group 369 * on the outgoing interface, and the caller did not 370 * forbid loopback, loop back a copy. 371 */ 372 ip_mloopback(ifp, m, dst); 373 } 374 #ifdef MROUTING 375 else { 376 /* 377 * If we are acting as a multicast router, perform 378 * multicast forwarding as if the packet had just 379 * arrived on the interface to which we are about 380 * to send. The multicast forwarding function 381 * recursively calls this function, using the 382 * IP_FORWARDING flag to prevent infinite recursion. 383 * 384 * Multicasts that are looped back by ip_mloopback(), 385 * above, will be forwarded by the ip_input() routine, 386 * if necessary. 387 */ 388 extern struct socket *ip_mrouter; 389 390 if (ip_mrouter && (flags & IP_FORWARDING) == 0) { 391 if (ip_mforward(m, ifp) != 0) { 392 m_freem(m); 393 goto done; 394 } 395 } 396 } 397 #endif 398 /* 399 * Multicasts with a time-to-live of zero may be looped- 400 * back, above, but must not be transmitted on a network. 401 * Also, multicasts addressed to the loopback interface 402 * are not sent -- the above call to ip_mloopback() will 403 * loop back a copy if this host actually belongs to the 404 * destination group on the loopback interface. 405 */ 406 if (ip->ip_ttl == 0 || (ifp->if_flags & IFF_LOOPBACK) != 0) { 407 m_freem(m); 408 goto done; 409 } 410 411 goto sendit; 412 } 413 #ifndef notdef 414 /* 415 * If source address not specified yet, use address 416 * of outgoing interface. 417 */ 418 if (in_nullhost(ip->ip_src)) 419 ip->ip_src = ia->ia_addr.sin_addr; 420 #endif 421 422 /* 423 * packets with Class-D address as source are not valid per 424 * RFC 1112 425 */ 426 if (IN_MULTICAST(ip->ip_src.s_addr)) { 427 ipstat.ips_odropped++; 428 error = EADDRNOTAVAIL; 429 goto bad; 430 } 431 432 /* 433 * Look for broadcast address and 434 * and verify user is allowed to send 435 * such a packet. 436 */ 437 if (in_broadcast(dst->sin_addr, ifp)) { 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 (ntohs(ip->ip_len) > ifp->if_mtu) { 448 error = EMSGSIZE; 449 goto bad; 450 } 451 m->m_flags |= M_BCAST; 452 } else 453 m->m_flags &= ~M_BCAST; 454 455 sendit: 456 /* 457 * If we're doing Path MTU Discovery, we need to set DF unless 458 * the route's MTU is locked. 459 */ 460 if ((flags & IP_MTUDISC) != 0 && ro->ro_rt != NULL && 461 (ro->ro_rt->rt_rmx.rmx_locks & RTV_MTU) == 0) 462 ip->ip_off |= htons(IP_DF); 463 464 /* Remember the current ip_len */ 465 ip_len = ntohs(ip->ip_len); 466 467 #ifdef IPSEC 468 /* get SP for this packet */ 469 if (so == NULL) 470 sp = ipsec4_getpolicybyaddr(m, IPSEC_DIR_OUTBOUND, 471 flags, &error); 472 else 473 sp = ipsec4_getpolicybysock(m, IPSEC_DIR_OUTBOUND, so, &error); 474 475 if (sp == NULL) { 476 ipsecstat.out_inval++; 477 goto bad; 478 } 479 480 error = 0; 481 482 /* check policy */ 483 switch (sp->policy) { 484 case IPSEC_POLICY_DISCARD: 485 /* 486 * This packet is just discarded. 487 */ 488 ipsecstat.out_polvio++; 489 goto bad; 490 491 case IPSEC_POLICY_BYPASS: 492 case IPSEC_POLICY_NONE: 493 /* no need to do IPsec. */ 494 goto skip_ipsec; 495 496 case IPSEC_POLICY_IPSEC: 497 if (sp->req == NULL) { 498 /* XXX should be panic ? */ 499 printf("ip_output: No IPsec request specified.\n"); 500 error = EINVAL; 501 goto bad; 502 } 503 break; 504 505 case IPSEC_POLICY_ENTRUST: 506 default: 507 printf("ip_output: Invalid policy found. %d\n", sp->policy); 508 } 509 510 /* 511 * ipsec4_output() expects ip_len and ip_off in network 512 * order. They have been set to network order above. 513 */ 514 515 { 516 struct ipsec_output_state state; 517 bzero(&state, sizeof(state)); 518 state.m = m; 519 if (flags & IP_ROUTETOIF) { 520 state.ro = &iproute; 521 bzero(&iproute, sizeof(iproute)); 522 } else 523 state.ro = ro; 524 state.dst = (struct sockaddr *)dst; 525 526 /* 527 * We can't defer the checksum of payload data if 528 * we're about to encrypt/authenticate it. 529 * 530 * XXX When we support crypto offloading functions of 531 * XXX network interfaces, we need to reconsider this, 532 * XXX since it's likely that they'll support checksumming, 533 * XXX as well. 534 */ 535 if (m->m_pkthdr.csum_flags & (M_CSUM_TCPv4|M_CSUM_UDPv4)) { 536 in_delayed_cksum(m); 537 m->m_pkthdr.csum_flags &= ~(M_CSUM_TCPv4|M_CSUM_UDPv4); 538 } 539 540 error = ipsec4_output(&state, sp, flags); 541 542 m = state.m; 543 if (flags & IP_ROUTETOIF) { 544 /* 545 * if we have tunnel mode SA, we may need to ignore 546 * IP_ROUTETOIF. 547 */ 548 if (state.ro != &iproute || state.ro->ro_rt != NULL) { 549 flags &= ~IP_ROUTETOIF; 550 ro = state.ro; 551 } 552 } else 553 ro = state.ro; 554 dst = (struct sockaddr_in *)state.dst; 555 if (error) { 556 /* mbuf is already reclaimed in ipsec4_output. */ 557 m0 = NULL; 558 switch (error) { 559 case EHOSTUNREACH: 560 case ENETUNREACH: 561 case EMSGSIZE: 562 case ENOBUFS: 563 case ENOMEM: 564 break; 565 default: 566 printf("ip4_output (ipsec): error code %d\n", error); 567 /*fall through*/ 568 case ENOENT: 569 /* don't show these error codes to the user */ 570 error = 0; 571 break; 572 } 573 goto bad; 574 } 575 576 /* be sure to update variables that are affected by ipsec4_output() */ 577 ip = mtod(m, struct ip *); 578 hlen = ip->ip_hl << 2; 579 ip_len = ntohs(ip->ip_len); 580 581 if (ro->ro_rt == NULL) { 582 if ((flags & IP_ROUTETOIF) == 0) { 583 printf("ip_output: " 584 "can't update route after IPsec processing\n"); 585 error = EHOSTUNREACH; /*XXX*/ 586 goto bad; 587 } 588 } else { 589 /* nobody uses ia beyond here */ 590 if (state.encap) 591 ifp = ro->ro_rt->rt_ifp; 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 sp = ipsec4_checkpolicy(m, IPSEC_DIR_OUTBOUND, flags, 616 &error, inp); 617 } 618 /* 619 * There are four return cases: 620 * sp != NULL apply IPsec policy 621 * sp == NULL, error == 0 no IPsec handling needed 622 * sp == NULL, error == -EINVAL discard packet w/o error 623 * sp == NULL, error != 0 discard packet, report error 624 */ 625 if (sp != NULL) { 626 /* Loop detection, check if ipsec processing already done */ 627 IPSEC_ASSERT(sp->req != NULL, ("ip_output: no ipsec request")); 628 for (mtag = m_tag_first(m); mtag != NULL; 629 mtag = m_tag_next(m, mtag)) { 630 #ifdef MTAG_ABI_COMPAT 631 if (mtag->m_tag_cookie != MTAG_ABI_COMPAT) 632 continue; 633 #endif 634 if (mtag->m_tag_id != PACKET_TAG_IPSEC_OUT_DONE && 635 mtag->m_tag_id != PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED) 636 continue; 637 /* 638 * Check if policy has an SA associated with it. 639 * This can happen when an SP has yet to acquire 640 * an SA; e.g. on first reference. If it occurs, 641 * then we let ipsec4_process_packet do its thing. 642 */ 643 if (sp->req->sav == NULL) 644 break; 645 tdbi = (struct tdb_ident *)(mtag + 1); 646 if (tdbi->spi == sp->req->sav->spi && 647 tdbi->proto == sp->req->sav->sah->saidx.proto && 648 bcmp(&tdbi->dst, &sp->req->sav->sah->saidx.dst, 649 sizeof (union sockaddr_union)) == 0) { 650 /* 651 * No IPsec processing is needed, free 652 * reference to SP. 653 * 654 * NB: null pointer to avoid free at 655 * done: below. 656 */ 657 KEY_FREESP(&sp), sp = NULL; 658 splx(s); 659 goto spd_done; 660 } 661 } 662 663 /* 664 * Do delayed checksums now because we send before 665 * this is done in the normal processing path. 666 */ 667 if (m->m_pkthdr.csum_flags & (M_CSUM_TCPv4|M_CSUM_UDPv4)) { 668 in_delayed_cksum(m); 669 m->m_pkthdr.csum_flags &= ~(M_CSUM_TCPv4|M_CSUM_UDPv4); 670 } 671 672 #ifdef __FreeBSD__ 673 ip->ip_len = htons(ip->ip_len); 674 ip->ip_off = htons(ip->ip_off); 675 #endif 676 677 /* NB: callee frees mbuf */ 678 error = ipsec4_process_packet(m, sp->req, flags, 0); 679 /* 680 * Preserve KAME behaviour: ENOENT can be returned 681 * when an SA acquire is in progress. Don't propagate 682 * this to user-level; it confuses applications. 683 * 684 * XXX this will go away when the SADB is redone. 685 */ 686 if (error == ENOENT) 687 error = 0; 688 splx(s); 689 goto done; 690 } else { 691 splx(s); 692 693 if (error != 0) { 694 /* 695 * Hack: -EINVAL is used to signal that a packet 696 * should be silently discarded. This is typically 697 * because we asked key management for an SA and 698 * it was delayed (e.g. kicked up to IKE). 699 */ 700 if (error == -EINVAL) 701 error = 0; 702 goto bad; 703 } else { 704 /* No IPsec processing for this packet. */ 705 } 706 #ifdef notyet 707 /* 708 * If deferred crypto processing is needed, check that 709 * the interface supports it. 710 */ 711 mtag = m_tag_find(m, PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED, NULL); 712 if (mtag != NULL && (ifp->if_capenable & IFCAP_IPSEC) == 0) { 713 /* notify IPsec to do its own crypto */ 714 ipsp_skipcrypto_unmark((struct tdb_ident *)(mtag + 1)); 715 error = EHOSTUNREACH; 716 goto bad; 717 } 718 #endif 719 } 720 spd_done: 721 #endif /* FAST_IPSEC */ 722 723 #ifdef PFIL_HOOKS 724 /* 725 * Run through list of hooks for output packets. 726 */ 727 if ((error = pfil_run_hooks(&inet_pfil_hook, &m, ifp, PFIL_OUT)) != 0) 728 goto done; 729 if (m == NULL) 730 goto done; 731 732 ip = mtod(m, struct ip *); 733 hlen = ip->ip_hl << 2; 734 #endif /* PFIL_HOOKS */ 735 736 m->m_pkthdr.csum_flags |= M_CSUM_IPv4; 737 sw_csum = m->m_pkthdr.csum_flags & ~ifp->if_csum_flags_tx; 738 /* 739 * If small enough for mtu of path, can just send directly. 740 */ 741 if (ip_len <= mtu) { 742 #if IFA_STATS 743 /* 744 * search for the source address structure to 745 * maintain output statistics. 746 */ 747 INADDR_TO_IA(ip->ip_src, ia); 748 if (ia) 749 ia->ia_ifa.ifa_data.ifad_outbytes += ip_len; 750 #endif 751 /* 752 * Always initialize the sum to 0! Some HW assisted 753 * checksumming requires this. 754 */ 755 ip->ip_sum = 0; 756 757 /* 758 * Perform any checksums that the hardware can't do 759 * for us. 760 * 761 * XXX Does any hardware require the {th,uh}_sum 762 * XXX fields to be 0? 763 */ 764 if (sw_csum & M_CSUM_IPv4) { 765 ip->ip_sum = in_cksum(m, hlen); 766 m->m_pkthdr.csum_flags &= ~M_CSUM_IPv4; 767 } 768 if (sw_csum & (M_CSUM_TCPv4|M_CSUM_UDPv4)) { 769 in_delayed_cksum(m); 770 m->m_pkthdr.csum_flags &= ~(M_CSUM_TCPv4|M_CSUM_UDPv4); 771 } 772 773 #ifdef IPSEC 774 /* clean ipsec history once it goes out of the node */ 775 ipsec_delaux(m); 776 #endif 777 error = (*ifp->if_output)(ifp, m, sintosa(dst), ro->ro_rt); 778 goto done; 779 } 780 781 /* 782 * We can't use HW checksumming if we're about to 783 * to fragment the packet. 784 * 785 * XXX Some hardware can do this. 786 */ 787 if (m->m_pkthdr.csum_flags & (M_CSUM_TCPv4|M_CSUM_UDPv4)) { 788 in_delayed_cksum(m); 789 m->m_pkthdr.csum_flags &= ~(M_CSUM_TCPv4|M_CSUM_UDPv4); 790 } 791 792 /* 793 * Too large for interface; fragment if possible. 794 * Must be able to put at least 8 bytes per fragment. 795 */ 796 if (ntohs(ip->ip_off) & IP_DF) { 797 if (flags & IP_RETURNMTU) 798 *mtu_p = mtu; 799 error = EMSGSIZE; 800 ipstat.ips_cantfrag++; 801 goto bad; 802 } 803 804 error = ip_fragment(m, ifp, mtu); 805 if (error) { 806 m = NULL; 807 goto bad; 808 } 809 810 for (; m; m = m0) { 811 m0 = m->m_nextpkt; 812 m->m_nextpkt = 0; 813 if (error == 0) { 814 #if IFA_STATS 815 /* 816 * search for the source address structure to 817 * maintain output statistics. 818 */ 819 INADDR_TO_IA(ip->ip_src, ia); 820 if (ia) { 821 ia->ia_ifa.ifa_data.ifad_outbytes += 822 ntohs(ip->ip_len); 823 } 824 #endif 825 #ifdef IPSEC 826 /* clean ipsec history once it goes out of the node */ 827 ipsec_delaux(m); 828 #endif 829 KASSERT((m->m_pkthdr.csum_flags & 830 (M_CSUM_UDPv4 | M_CSUM_TCPv4)) == 0); 831 error = (*ifp->if_output)(ifp, m, sintosa(dst), 832 ro->ro_rt); 833 } else 834 m_freem(m); 835 } 836 837 if (error == 0) 838 ipstat.ips_fragmented++; 839 done: 840 if (ro == &iproute && (flags & IP_ROUTETOIF) == 0 && ro->ro_rt) { 841 RTFREE(ro->ro_rt); 842 ro->ro_rt = 0; 843 } 844 845 #ifdef IPSEC 846 if (sp != NULL) { 847 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 848 printf("DP ip_output call free SP:%p\n", sp)); 849 key_freesp(sp); 850 } 851 #endif /* IPSEC */ 852 #ifdef FAST_IPSEC 853 if (sp != NULL) 854 KEY_FREESP(&sp); 855 #endif /* FAST_IPSEC */ 856 857 return (error); 858 bad: 859 m_freem(m); 860 goto done; 861 } 862 863 int 864 ip_fragment(struct mbuf *m, struct ifnet *ifp, u_long mtu) 865 { 866 struct ip *ip, *mhip; 867 struct mbuf *m0; 868 int len, hlen, off; 869 int mhlen, firstlen; 870 struct mbuf **mnext; 871 int sw_csum; 872 int fragments = 0; 873 int s; 874 int error = 0; 875 876 ip = mtod(m, struct ip *); 877 hlen = ip->ip_hl << 2; 878 sw_csum = m->m_pkthdr.csum_flags & ~ifp->if_csum_flags_tx; 879 880 len = (mtu - hlen) &~ 7; 881 if (len < 8) { 882 m_freem(m); 883 return (EMSGSIZE); 884 } 885 886 firstlen = len; 887 mnext = &m->m_nextpkt; 888 889 /* 890 * Loop through length of segment after first fragment, 891 * make new header and copy data of each part and link onto chain. 892 */ 893 m0 = m; 894 mhlen = sizeof (struct ip); 895 for (off = hlen + len; off < ntohs(ip->ip_len); off += len) { 896 MGETHDR(m, M_DONTWAIT, MT_HEADER); 897 if (m == 0) { 898 error = ENOBUFS; 899 ipstat.ips_odropped++; 900 goto sendorfree; 901 } 902 MCLAIM(m, m0->m_owner); 903 *mnext = m; 904 mnext = &m->m_nextpkt; 905 m->m_data += max_linkhdr; 906 mhip = mtod(m, struct ip *); 907 *mhip = *ip; 908 /* we must inherit MCAST and BCAST flags */ 909 m->m_flags |= m0->m_flags & (M_MCAST|M_BCAST); 910 if (hlen > sizeof (struct ip)) { 911 mhlen = ip_optcopy(ip, mhip) + sizeof (struct ip); 912 mhip->ip_hl = mhlen >> 2; 913 } 914 m->m_len = mhlen; 915 mhip->ip_off = ((off - hlen) >> 3) + 916 (ntohs(ip->ip_off) & ~IP_MF); 917 if (ip->ip_off & htons(IP_MF)) 918 mhip->ip_off |= IP_MF; 919 if (off + len >= ntohs(ip->ip_len)) 920 len = ntohs(ip->ip_len) - off; 921 else 922 mhip->ip_off |= IP_MF; 923 HTONS(mhip->ip_off); 924 mhip->ip_len = htons((u_int16_t)(len + mhlen)); 925 m->m_next = m_copy(m0, off, len); 926 if (m->m_next == 0) { 927 error = ENOBUFS; /* ??? */ 928 ipstat.ips_odropped++; 929 goto sendorfree; 930 } 931 m->m_pkthdr.len = mhlen + len; 932 m->m_pkthdr.rcvif = (struct ifnet *)0; 933 mhip->ip_sum = 0; 934 if (sw_csum & M_CSUM_IPv4) { 935 mhip->ip_sum = in_cksum(m, mhlen); 936 KASSERT((m->m_pkthdr.csum_flags & M_CSUM_IPv4) == 0); 937 } else { 938 m->m_pkthdr.csum_flags |= M_CSUM_IPv4; 939 } 940 ipstat.ips_ofragments++; 941 fragments++; 942 } 943 /* 944 * Update first fragment by trimming what's been copied out 945 * and updating header, then send each fragment (in order). 946 */ 947 m = m0; 948 m_adj(m, hlen + firstlen - ntohs(ip->ip_len)); 949 m->m_pkthdr.len = hlen + firstlen; 950 ip->ip_len = htons((u_int16_t)m->m_pkthdr.len); 951 ip->ip_off |= htons(IP_MF); 952 ip->ip_sum = 0; 953 if (sw_csum & M_CSUM_IPv4) { 954 ip->ip_sum = in_cksum(m, hlen); 955 m->m_pkthdr.csum_flags &= ~M_CSUM_IPv4; 956 } else { 957 KASSERT(m->m_pkthdr.csum_flags & M_CSUM_IPv4); 958 } 959 sendorfree: 960 /* 961 * If there is no room for all the fragments, don't queue 962 * any of them. 963 */ 964 s = splnet(); 965 if (ifp->if_snd.ifq_maxlen - ifp->if_snd.ifq_len < fragments && 966 error == 0) { 967 error = ENOBUFS; 968 ipstat.ips_odropped++; 969 IFQ_INC_DROPS(&ifp->if_snd); 970 } 971 splx(s); 972 if (error) { 973 for (m = m0; m; m = m0) { 974 m0 = m->m_nextpkt; 975 m->m_nextpkt = NULL; 976 m_freem(m); 977 } 978 } 979 return (error); 980 } 981 982 /* 983 * Process a delayed payload checksum calculation. 984 */ 985 void 986 in_delayed_cksum(struct mbuf *m) 987 { 988 struct ip *ip; 989 u_int16_t csum, offset; 990 991 ip = mtod(m, struct ip *); 992 offset = ip->ip_hl << 2; 993 csum = in4_cksum(m, 0, offset, ntohs(ip->ip_len) - offset); 994 if (csum == 0 && (m->m_pkthdr.csum_flags & M_CSUM_UDPv4) != 0) 995 csum = 0xffff; 996 997 offset += m->m_pkthdr.csum_data; /* checksum offset */ 998 999 if ((offset + sizeof(u_int16_t)) > m->m_len) { 1000 /* This happen when ip options were inserted 1001 printf("in_delayed_cksum: pullup len %d off %d proto %d\n", 1002 m->m_len, offset, ip->ip_p); 1003 */ 1004 m_copyback(m, offset, sizeof(csum), (caddr_t) &csum); 1005 } else 1006 *(u_int16_t *)(mtod(m, caddr_t) + offset) = csum; 1007 } 1008 1009 /* 1010 * Determine the maximum length of the options to be inserted; 1011 * we would far rather allocate too much space rather than too little. 1012 */ 1013 1014 u_int 1015 ip_optlen(inp) 1016 struct inpcb *inp; 1017 { 1018 struct mbuf *m = inp->inp_options; 1019 1020 if (m && m->m_len > offsetof(struct ipoption, ipopt_dst)) 1021 return (m->m_len - offsetof(struct ipoption, ipopt_dst)); 1022 else 1023 return 0; 1024 } 1025 1026 1027 /* 1028 * Insert IP options into preformed packet. 1029 * Adjust IP destination as required for IP source routing, 1030 * as indicated by a non-zero in_addr at the start of the options. 1031 */ 1032 static struct mbuf * 1033 ip_insertoptions(m, opt, phlen) 1034 struct mbuf *m; 1035 struct mbuf *opt; 1036 int *phlen; 1037 { 1038 struct ipoption *p = mtod(opt, struct ipoption *); 1039 struct mbuf *n; 1040 struct ip *ip = mtod(m, struct ip *); 1041 unsigned optlen; 1042 1043 optlen = opt->m_len - sizeof(p->ipopt_dst); 1044 if (optlen + ntohs(ip->ip_len) > IP_MAXPACKET) 1045 return (m); /* XXX should fail */ 1046 if (!in_nullhost(p->ipopt_dst)) 1047 ip->ip_dst = p->ipopt_dst; 1048 if (M_READONLY(m) || M_LEADINGSPACE(m) < optlen) { 1049 MGETHDR(n, M_DONTWAIT, MT_HEADER); 1050 if (n == 0) 1051 return (m); 1052 MCLAIM(n, m->m_owner); 1053 M_COPY_PKTHDR(n, m); 1054 m_tag_delete_chain(m, NULL); 1055 m->m_flags &= ~M_PKTHDR; 1056 m->m_len -= sizeof(struct ip); 1057 m->m_data += sizeof(struct ip); 1058 n->m_next = m; 1059 m = n; 1060 m->m_len = optlen + sizeof(struct ip); 1061 m->m_data += max_linkhdr; 1062 bcopy((caddr_t)ip, mtod(m, caddr_t), sizeof(struct ip)); 1063 } else { 1064 m->m_data -= optlen; 1065 m->m_len += optlen; 1066 memmove(mtod(m, caddr_t), ip, sizeof(struct ip)); 1067 } 1068 m->m_pkthdr.len += optlen; 1069 ip = mtod(m, struct ip *); 1070 bcopy((caddr_t)p->ipopt_list, (caddr_t)(ip + 1), (unsigned)optlen); 1071 *phlen = sizeof(struct ip) + optlen; 1072 ip->ip_len = htons(ntohs(ip->ip_len) + optlen); 1073 return (m); 1074 } 1075 1076 /* 1077 * Copy options from ip to jp, 1078 * omitting those not copied during fragmentation. 1079 */ 1080 int 1081 ip_optcopy(ip, jp) 1082 struct ip *ip, *jp; 1083 { 1084 u_char *cp, *dp; 1085 int opt, optlen, cnt; 1086 1087 cp = (u_char *)(ip + 1); 1088 dp = (u_char *)(jp + 1); 1089 cnt = (ip->ip_hl << 2) - sizeof (struct ip); 1090 for (; cnt > 0; cnt -= optlen, cp += optlen) { 1091 opt = cp[0]; 1092 if (opt == IPOPT_EOL) 1093 break; 1094 if (opt == IPOPT_NOP) { 1095 /* Preserve for IP mcast tunnel's LSRR alignment. */ 1096 *dp++ = IPOPT_NOP; 1097 optlen = 1; 1098 continue; 1099 } 1100 #ifdef DIAGNOSTIC 1101 if (cnt < IPOPT_OLEN + sizeof(*cp)) 1102 panic("malformed IPv4 option passed to ip_optcopy"); 1103 #endif 1104 optlen = cp[IPOPT_OLEN]; 1105 #ifdef DIAGNOSTIC 1106 if (optlen < IPOPT_OLEN + sizeof(*cp) || optlen > cnt) 1107 panic("malformed IPv4 option passed to ip_optcopy"); 1108 #endif 1109 /* bogus lengths should have been caught by ip_dooptions */ 1110 if (optlen > cnt) 1111 optlen = cnt; 1112 if (IPOPT_COPIED(opt)) { 1113 bcopy((caddr_t)cp, (caddr_t)dp, (unsigned)optlen); 1114 dp += optlen; 1115 } 1116 } 1117 for (optlen = dp - (u_char *)(jp+1); optlen & 0x3; optlen++) 1118 *dp++ = IPOPT_EOL; 1119 return (optlen); 1120 } 1121 1122 /* 1123 * IP socket option processing. 1124 */ 1125 int 1126 ip_ctloutput(op, so, level, optname, mp) 1127 int op; 1128 struct socket *so; 1129 int level, optname; 1130 struct mbuf **mp; 1131 { 1132 struct inpcb *inp = sotoinpcb(so); 1133 struct mbuf *m = *mp; 1134 int optval = 0; 1135 int error = 0; 1136 #if defined(IPSEC) || defined(FAST_IPSEC) 1137 struct proc *p = curproc; /*XXX*/ 1138 #endif 1139 1140 if (level != IPPROTO_IP) { 1141 error = EINVAL; 1142 if (op == PRCO_SETOPT && *mp) 1143 (void) m_free(*mp); 1144 } else switch (op) { 1145 1146 case PRCO_SETOPT: 1147 switch (optname) { 1148 case IP_OPTIONS: 1149 #ifdef notyet 1150 case IP_RETOPTS: 1151 return (ip_pcbopts(optname, &inp->inp_options, m)); 1152 #else 1153 return (ip_pcbopts(&inp->inp_options, m)); 1154 #endif 1155 1156 case IP_TOS: 1157 case IP_TTL: 1158 case IP_RECVOPTS: 1159 case IP_RECVRETOPTS: 1160 case IP_RECVDSTADDR: 1161 case IP_RECVIF: 1162 if (m == NULL || m->m_len != sizeof(int)) 1163 error = EINVAL; 1164 else { 1165 optval = *mtod(m, int *); 1166 switch (optname) { 1167 1168 case IP_TOS: 1169 inp->inp_ip.ip_tos = optval; 1170 break; 1171 1172 case IP_TTL: 1173 inp->inp_ip.ip_ttl = optval; 1174 break; 1175 #define OPTSET(bit) \ 1176 if (optval) \ 1177 inp->inp_flags |= bit; \ 1178 else \ 1179 inp->inp_flags &= ~bit; 1180 1181 case IP_RECVOPTS: 1182 OPTSET(INP_RECVOPTS); 1183 break; 1184 1185 case IP_RECVRETOPTS: 1186 OPTSET(INP_RECVRETOPTS); 1187 break; 1188 1189 case IP_RECVDSTADDR: 1190 OPTSET(INP_RECVDSTADDR); 1191 break; 1192 1193 case IP_RECVIF: 1194 OPTSET(INP_RECVIF); 1195 break; 1196 } 1197 } 1198 break; 1199 #undef OPTSET 1200 1201 case IP_MULTICAST_IF: 1202 case IP_MULTICAST_TTL: 1203 case IP_MULTICAST_LOOP: 1204 case IP_ADD_MEMBERSHIP: 1205 case IP_DROP_MEMBERSHIP: 1206 error = ip_setmoptions(optname, &inp->inp_moptions, m); 1207 break; 1208 1209 case IP_PORTRANGE: 1210 if (m == 0 || m->m_len != sizeof(int)) 1211 error = EINVAL; 1212 else { 1213 optval = *mtod(m, int *); 1214 1215 switch (optval) { 1216 1217 case IP_PORTRANGE_DEFAULT: 1218 case IP_PORTRANGE_HIGH: 1219 inp->inp_flags &= ~(INP_LOWPORT); 1220 break; 1221 1222 case IP_PORTRANGE_LOW: 1223 inp->inp_flags |= INP_LOWPORT; 1224 break; 1225 1226 default: 1227 error = EINVAL; 1228 break; 1229 } 1230 } 1231 break; 1232 1233 #if defined(IPSEC) || defined(FAST_IPSEC) 1234 case IP_IPSEC_POLICY: 1235 { 1236 caddr_t req = NULL; 1237 size_t len = 0; 1238 int priv = 0; 1239 1240 #ifdef __NetBSD__ 1241 if (p == 0 || suser(p->p_ucred, &p->p_acflag)) 1242 priv = 0; 1243 else 1244 priv = 1; 1245 #else 1246 priv = (in6p->in6p_socket->so_state & SS_PRIV); 1247 #endif 1248 if (m) { 1249 req = mtod(m, caddr_t); 1250 len = m->m_len; 1251 } 1252 error = ipsec4_set_policy(inp, optname, req, len, priv); 1253 break; 1254 } 1255 #endif /*IPSEC*/ 1256 1257 default: 1258 error = ENOPROTOOPT; 1259 break; 1260 } 1261 if (m) 1262 (void)m_free(m); 1263 break; 1264 1265 case PRCO_GETOPT: 1266 switch (optname) { 1267 case IP_OPTIONS: 1268 case IP_RETOPTS: 1269 *mp = m = m_get(M_WAIT, MT_SOOPTS); 1270 MCLAIM(m, so->so_mowner); 1271 if (inp->inp_options) { 1272 m->m_len = inp->inp_options->m_len; 1273 bcopy(mtod(inp->inp_options, caddr_t), 1274 mtod(m, caddr_t), (unsigned)m->m_len); 1275 } else 1276 m->m_len = 0; 1277 break; 1278 1279 case IP_TOS: 1280 case IP_TTL: 1281 case IP_RECVOPTS: 1282 case IP_RECVRETOPTS: 1283 case IP_RECVDSTADDR: 1284 case IP_RECVIF: 1285 case IP_ERRORMTU: 1286 *mp = m = m_get(M_WAIT, MT_SOOPTS); 1287 MCLAIM(m, so->so_mowner); 1288 m->m_len = sizeof(int); 1289 switch (optname) { 1290 1291 case IP_TOS: 1292 optval = inp->inp_ip.ip_tos; 1293 break; 1294 1295 case IP_TTL: 1296 optval = inp->inp_ip.ip_ttl; 1297 break; 1298 1299 case IP_ERRORMTU: 1300 optval = inp->inp_errormtu; 1301 break; 1302 1303 #define OPTBIT(bit) (inp->inp_flags & bit ? 1 : 0) 1304 1305 case IP_RECVOPTS: 1306 optval = OPTBIT(INP_RECVOPTS); 1307 break; 1308 1309 case IP_RECVRETOPTS: 1310 optval = OPTBIT(INP_RECVRETOPTS); 1311 break; 1312 1313 case IP_RECVDSTADDR: 1314 optval = OPTBIT(INP_RECVDSTADDR); 1315 break; 1316 1317 case IP_RECVIF: 1318 optval = OPTBIT(INP_RECVIF); 1319 break; 1320 } 1321 *mtod(m, int *) = optval; 1322 break; 1323 1324 #if defined(IPSEC) || defined(FAST_IPSEC) 1325 case IP_IPSEC_POLICY: 1326 { 1327 caddr_t req = NULL; 1328 size_t len = 0; 1329 1330 if (m) { 1331 req = mtod(m, caddr_t); 1332 len = m->m_len; 1333 } 1334 error = ipsec4_get_policy(inp, req, len, mp); 1335 break; 1336 } 1337 #endif /*IPSEC*/ 1338 1339 case IP_MULTICAST_IF: 1340 case IP_MULTICAST_TTL: 1341 case IP_MULTICAST_LOOP: 1342 case IP_ADD_MEMBERSHIP: 1343 case IP_DROP_MEMBERSHIP: 1344 error = ip_getmoptions(optname, inp->inp_moptions, mp); 1345 if (*mp) 1346 MCLAIM(*mp, so->so_mowner); 1347 break; 1348 1349 case IP_PORTRANGE: 1350 *mp = m = m_get(M_WAIT, MT_SOOPTS); 1351 MCLAIM(m, so->so_mowner); 1352 m->m_len = sizeof(int); 1353 1354 if (inp->inp_flags & INP_LOWPORT) 1355 optval = IP_PORTRANGE_LOW; 1356 else 1357 optval = IP_PORTRANGE_DEFAULT; 1358 1359 *mtod(m, int *) = optval; 1360 break; 1361 1362 default: 1363 error = ENOPROTOOPT; 1364 break; 1365 } 1366 break; 1367 } 1368 return (error); 1369 } 1370 1371 /* 1372 * Set up IP options in pcb for insertion in output packets. 1373 * Store in mbuf with pointer in pcbopt, adding pseudo-option 1374 * with destination address if source routed. 1375 */ 1376 int 1377 #ifdef notyet 1378 ip_pcbopts(optname, pcbopt, m) 1379 int optname; 1380 #else 1381 ip_pcbopts(pcbopt, m) 1382 #endif 1383 struct mbuf **pcbopt; 1384 struct mbuf *m; 1385 { 1386 int cnt, optlen; 1387 u_char *cp; 1388 u_char opt; 1389 1390 /* turn off any old options */ 1391 if (*pcbopt) 1392 (void)m_free(*pcbopt); 1393 *pcbopt = 0; 1394 if (m == (struct mbuf *)0 || m->m_len == 0) { 1395 /* 1396 * Only turning off any previous options. 1397 */ 1398 if (m) 1399 (void)m_free(m); 1400 return (0); 1401 } 1402 1403 #ifndef __vax__ 1404 if (m->m_len % sizeof(int32_t)) 1405 goto bad; 1406 #endif 1407 /* 1408 * IP first-hop destination address will be stored before 1409 * actual options; move other options back 1410 * and clear it when none present. 1411 */ 1412 if (m->m_data + m->m_len + sizeof(struct in_addr) >= &m->m_dat[MLEN]) 1413 goto bad; 1414 cnt = m->m_len; 1415 m->m_len += sizeof(struct in_addr); 1416 cp = mtod(m, u_char *) + sizeof(struct in_addr); 1417 memmove(cp, mtod(m, caddr_t), (unsigned)cnt); 1418 bzero(mtod(m, caddr_t), sizeof(struct in_addr)); 1419 1420 for (; cnt > 0; cnt -= optlen, cp += optlen) { 1421 opt = cp[IPOPT_OPTVAL]; 1422 if (opt == IPOPT_EOL) 1423 break; 1424 if (opt == IPOPT_NOP) 1425 optlen = 1; 1426 else { 1427 if (cnt < IPOPT_OLEN + sizeof(*cp)) 1428 goto bad; 1429 optlen = cp[IPOPT_OLEN]; 1430 if (optlen < IPOPT_OLEN + sizeof(*cp) || optlen > cnt) 1431 goto bad; 1432 } 1433 switch (opt) { 1434 1435 default: 1436 break; 1437 1438 case IPOPT_LSRR: 1439 case IPOPT_SSRR: 1440 /* 1441 * user process specifies route as: 1442 * ->A->B->C->D 1443 * D must be our final destination (but we can't 1444 * check that since we may not have connected yet). 1445 * A is first hop destination, which doesn't appear in 1446 * actual IP option, but is stored before the options. 1447 */ 1448 if (optlen < IPOPT_MINOFF - 1 + sizeof(struct in_addr)) 1449 goto bad; 1450 m->m_len -= sizeof(struct in_addr); 1451 cnt -= sizeof(struct in_addr); 1452 optlen -= sizeof(struct in_addr); 1453 cp[IPOPT_OLEN] = optlen; 1454 /* 1455 * Move first hop before start of options. 1456 */ 1457 bcopy((caddr_t)&cp[IPOPT_OFFSET+1], mtod(m, caddr_t), 1458 sizeof(struct in_addr)); 1459 /* 1460 * Then copy rest of options back 1461 * to close up the deleted entry. 1462 */ 1463 memmove(&cp[IPOPT_OFFSET+1], 1464 (caddr_t)(&cp[IPOPT_OFFSET+1] + sizeof(struct in_addr)), 1465 (unsigned)cnt + sizeof(struct in_addr)); 1466 break; 1467 } 1468 } 1469 if (m->m_len > MAX_IPOPTLEN + sizeof(struct in_addr)) 1470 goto bad; 1471 *pcbopt = m; 1472 return (0); 1473 1474 bad: 1475 (void)m_free(m); 1476 return (EINVAL); 1477 } 1478 1479 /* 1480 * following RFC1724 section 3.3, 0.0.0.0/8 is interpreted as interface index. 1481 */ 1482 static struct ifnet * 1483 ip_multicast_if(a, ifindexp) 1484 struct in_addr *a; 1485 int *ifindexp; 1486 { 1487 int ifindex; 1488 struct ifnet *ifp = NULL; 1489 struct in_ifaddr *ia; 1490 1491 if (ifindexp) 1492 *ifindexp = 0; 1493 if (ntohl(a->s_addr) >> 24 == 0) { 1494 ifindex = ntohl(a->s_addr) & 0xffffff; 1495 if (ifindex < 0 || if_indexlim <= ifindex) 1496 return NULL; 1497 ifp = ifindex2ifnet[ifindex]; 1498 if (!ifp) 1499 return NULL; 1500 if (ifindexp) 1501 *ifindexp = ifindex; 1502 } else { 1503 LIST_FOREACH(ia, &IN_IFADDR_HASH(a->s_addr), ia_hash) { 1504 if (in_hosteq(ia->ia_addr.sin_addr, *a) && 1505 (ia->ia_ifp->if_flags & IFF_MULTICAST) != 0) { 1506 ifp = ia->ia_ifp; 1507 break; 1508 } 1509 } 1510 } 1511 return ifp; 1512 } 1513 1514 /* 1515 * Set the IP multicast options in response to user setsockopt(). 1516 */ 1517 int 1518 ip_setmoptions(optname, imop, m) 1519 int optname; 1520 struct ip_moptions **imop; 1521 struct mbuf *m; 1522 { 1523 int error = 0; 1524 u_char loop; 1525 int i; 1526 struct in_addr addr; 1527 struct ip_mreq *mreq; 1528 struct ifnet *ifp; 1529 struct ip_moptions *imo = *imop; 1530 struct route ro; 1531 struct sockaddr_in *dst; 1532 int ifindex; 1533 1534 if (imo == NULL) { 1535 /* 1536 * No multicast option buffer attached to the pcb; 1537 * allocate one and initialize to default values. 1538 */ 1539 imo = (struct ip_moptions *)malloc(sizeof(*imo), M_IPMOPTS, 1540 M_WAITOK); 1541 1542 if (imo == NULL) 1543 return (ENOBUFS); 1544 *imop = imo; 1545 imo->imo_multicast_ifp = NULL; 1546 imo->imo_multicast_addr.s_addr = INADDR_ANY; 1547 imo->imo_multicast_ttl = IP_DEFAULT_MULTICAST_TTL; 1548 imo->imo_multicast_loop = IP_DEFAULT_MULTICAST_LOOP; 1549 imo->imo_num_memberships = 0; 1550 } 1551 1552 switch (optname) { 1553 1554 case IP_MULTICAST_IF: 1555 /* 1556 * Select the interface for outgoing multicast packets. 1557 */ 1558 if (m == NULL || m->m_len != sizeof(struct in_addr)) { 1559 error = EINVAL; 1560 break; 1561 } 1562 addr = *(mtod(m, struct in_addr *)); 1563 /* 1564 * INADDR_ANY is used to remove a previous selection. 1565 * When no interface is selected, a default one is 1566 * chosen every time a multicast packet is sent. 1567 */ 1568 if (in_nullhost(addr)) { 1569 imo->imo_multicast_ifp = NULL; 1570 break; 1571 } 1572 /* 1573 * The selected interface is identified by its local 1574 * IP address. Find the interface and confirm that 1575 * it supports multicasting. 1576 */ 1577 ifp = ip_multicast_if(&addr, &ifindex); 1578 if (ifp == NULL || (ifp->if_flags & IFF_MULTICAST) == 0) { 1579 error = EADDRNOTAVAIL; 1580 break; 1581 } 1582 imo->imo_multicast_ifp = ifp; 1583 if (ifindex) 1584 imo->imo_multicast_addr = addr; 1585 else 1586 imo->imo_multicast_addr.s_addr = INADDR_ANY; 1587 break; 1588 1589 case IP_MULTICAST_TTL: 1590 /* 1591 * Set the IP time-to-live for outgoing multicast packets. 1592 */ 1593 if (m == NULL || m->m_len != 1) { 1594 error = EINVAL; 1595 break; 1596 } 1597 imo->imo_multicast_ttl = *(mtod(m, u_char *)); 1598 break; 1599 1600 case IP_MULTICAST_LOOP: 1601 /* 1602 * Set the loopback flag for outgoing multicast packets. 1603 * Must be zero or one. 1604 */ 1605 if (m == NULL || m->m_len != 1 || 1606 (loop = *(mtod(m, u_char *))) > 1) { 1607 error = EINVAL; 1608 break; 1609 } 1610 imo->imo_multicast_loop = loop; 1611 break; 1612 1613 case IP_ADD_MEMBERSHIP: 1614 /* 1615 * Add a multicast group membership. 1616 * Group must be a valid IP multicast address. 1617 */ 1618 if (m == NULL || m->m_len != sizeof(struct ip_mreq)) { 1619 error = EINVAL; 1620 break; 1621 } 1622 mreq = mtod(m, struct ip_mreq *); 1623 if (!IN_MULTICAST(mreq->imr_multiaddr.s_addr)) { 1624 error = EINVAL; 1625 break; 1626 } 1627 /* 1628 * If no interface address was provided, use the interface of 1629 * the route to the given multicast address. 1630 */ 1631 if (in_nullhost(mreq->imr_interface)) { 1632 bzero((caddr_t)&ro, sizeof(ro)); 1633 ro.ro_rt = NULL; 1634 dst = satosin(&ro.ro_dst); 1635 dst->sin_len = sizeof(*dst); 1636 dst->sin_family = AF_INET; 1637 dst->sin_addr = mreq->imr_multiaddr; 1638 rtalloc(&ro); 1639 if (ro.ro_rt == NULL) { 1640 error = EADDRNOTAVAIL; 1641 break; 1642 } 1643 ifp = ro.ro_rt->rt_ifp; 1644 rtfree(ro.ro_rt); 1645 } else { 1646 ifp = ip_multicast_if(&mreq->imr_interface, NULL); 1647 } 1648 /* 1649 * See if we found an interface, and confirm that it 1650 * supports multicast. 1651 */ 1652 if (ifp == NULL || (ifp->if_flags & IFF_MULTICAST) == 0) { 1653 error = EADDRNOTAVAIL; 1654 break; 1655 } 1656 /* 1657 * See if the membership already exists or if all the 1658 * membership slots are full. 1659 */ 1660 for (i = 0; i < imo->imo_num_memberships; ++i) { 1661 if (imo->imo_membership[i]->inm_ifp == ifp && 1662 in_hosteq(imo->imo_membership[i]->inm_addr, 1663 mreq->imr_multiaddr)) 1664 break; 1665 } 1666 if (i < imo->imo_num_memberships) { 1667 error = EADDRINUSE; 1668 break; 1669 } 1670 if (i == IP_MAX_MEMBERSHIPS) { 1671 error = ETOOMANYREFS; 1672 break; 1673 } 1674 /* 1675 * Everything looks good; add a new record to the multicast 1676 * address list for the given interface. 1677 */ 1678 if ((imo->imo_membership[i] = 1679 in_addmulti(&mreq->imr_multiaddr, ifp)) == NULL) { 1680 error = ENOBUFS; 1681 break; 1682 } 1683 ++imo->imo_num_memberships; 1684 break; 1685 1686 case IP_DROP_MEMBERSHIP: 1687 /* 1688 * Drop a multicast group membership. 1689 * Group must be a valid IP multicast address. 1690 */ 1691 if (m == NULL || m->m_len != sizeof(struct ip_mreq)) { 1692 error = EINVAL; 1693 break; 1694 } 1695 mreq = mtod(m, struct ip_mreq *); 1696 if (!IN_MULTICAST(mreq->imr_multiaddr.s_addr)) { 1697 error = EINVAL; 1698 break; 1699 } 1700 /* 1701 * If an interface address was specified, get a pointer 1702 * to its ifnet structure. 1703 */ 1704 if (in_nullhost(mreq->imr_interface)) 1705 ifp = NULL; 1706 else { 1707 ifp = ip_multicast_if(&mreq->imr_interface, NULL); 1708 if (ifp == NULL) { 1709 error = EADDRNOTAVAIL; 1710 break; 1711 } 1712 } 1713 /* 1714 * Find the membership in the membership array. 1715 */ 1716 for (i = 0; i < imo->imo_num_memberships; ++i) { 1717 if ((ifp == NULL || 1718 imo->imo_membership[i]->inm_ifp == ifp) && 1719 in_hosteq(imo->imo_membership[i]->inm_addr, 1720 mreq->imr_multiaddr)) 1721 break; 1722 } 1723 if (i == imo->imo_num_memberships) { 1724 error = EADDRNOTAVAIL; 1725 break; 1726 } 1727 /* 1728 * Give up the multicast address record to which the 1729 * membership points. 1730 */ 1731 in_delmulti(imo->imo_membership[i]); 1732 /* 1733 * Remove the gap in the membership array. 1734 */ 1735 for (++i; i < imo->imo_num_memberships; ++i) 1736 imo->imo_membership[i-1] = imo->imo_membership[i]; 1737 --imo->imo_num_memberships; 1738 break; 1739 1740 default: 1741 error = EOPNOTSUPP; 1742 break; 1743 } 1744 1745 /* 1746 * If all options have default values, no need to keep the mbuf. 1747 */ 1748 if (imo->imo_multicast_ifp == NULL && 1749 imo->imo_multicast_ttl == IP_DEFAULT_MULTICAST_TTL && 1750 imo->imo_multicast_loop == IP_DEFAULT_MULTICAST_LOOP && 1751 imo->imo_num_memberships == 0) { 1752 free(*imop, M_IPMOPTS); 1753 *imop = NULL; 1754 } 1755 1756 return (error); 1757 } 1758 1759 /* 1760 * Return the IP multicast options in response to user getsockopt(). 1761 */ 1762 int 1763 ip_getmoptions(optname, imo, mp) 1764 int optname; 1765 struct ip_moptions *imo; 1766 struct mbuf **mp; 1767 { 1768 u_char *ttl; 1769 u_char *loop; 1770 struct in_addr *addr; 1771 struct in_ifaddr *ia; 1772 1773 *mp = m_get(M_WAIT, MT_SOOPTS); 1774 1775 switch (optname) { 1776 1777 case IP_MULTICAST_IF: 1778 addr = mtod(*mp, struct in_addr *); 1779 (*mp)->m_len = sizeof(struct in_addr); 1780 if (imo == NULL || imo->imo_multicast_ifp == NULL) 1781 *addr = zeroin_addr; 1782 else if (imo->imo_multicast_addr.s_addr) { 1783 /* return the value user has set */ 1784 *addr = imo->imo_multicast_addr; 1785 } else { 1786 IFP_TO_IA(imo->imo_multicast_ifp, ia); 1787 *addr = ia ? ia->ia_addr.sin_addr : zeroin_addr; 1788 } 1789 return (0); 1790 1791 case IP_MULTICAST_TTL: 1792 ttl = mtod(*mp, u_char *); 1793 (*mp)->m_len = 1; 1794 *ttl = imo ? imo->imo_multicast_ttl 1795 : IP_DEFAULT_MULTICAST_TTL; 1796 return (0); 1797 1798 case IP_MULTICAST_LOOP: 1799 loop = mtod(*mp, u_char *); 1800 (*mp)->m_len = 1; 1801 *loop = imo ? imo->imo_multicast_loop 1802 : IP_DEFAULT_MULTICAST_LOOP; 1803 return (0); 1804 1805 default: 1806 return (EOPNOTSUPP); 1807 } 1808 } 1809 1810 /* 1811 * Discard the IP multicast options. 1812 */ 1813 void 1814 ip_freemoptions(imo) 1815 struct ip_moptions *imo; 1816 { 1817 int i; 1818 1819 if (imo != NULL) { 1820 for (i = 0; i < imo->imo_num_memberships; ++i) 1821 in_delmulti(imo->imo_membership[i]); 1822 free(imo, M_IPMOPTS); 1823 } 1824 } 1825 1826 /* 1827 * Routine called from ip_output() to loop back a copy of an IP multicast 1828 * packet to the input queue of a specified interface. Note that this 1829 * calls the output routine of the loopback "driver", but with an interface 1830 * pointer that might NOT be &loif -- easier than replicating that code here. 1831 */ 1832 static void 1833 ip_mloopback(ifp, m, dst) 1834 struct ifnet *ifp; 1835 struct mbuf *m; 1836 struct sockaddr_in *dst; 1837 { 1838 struct ip *ip; 1839 struct mbuf *copym; 1840 1841 copym = m_copy(m, 0, M_COPYALL); 1842 if (copym != NULL 1843 && (copym->m_flags & M_EXT || copym->m_len < sizeof(struct ip))) 1844 copym = m_pullup(copym, sizeof(struct ip)); 1845 if (copym != NULL) { 1846 /* 1847 * We don't bother to fragment if the IP length is greater 1848 * than the interface's MTU. Can this possibly matter? 1849 */ 1850 ip = mtod(copym, struct ip *); 1851 1852 if (copym->m_pkthdr.csum_flags & (M_CSUM_TCPv4|M_CSUM_UDPv4)) { 1853 in_delayed_cksum(copym); 1854 copym->m_pkthdr.csum_flags &= 1855 ~(M_CSUM_TCPv4|M_CSUM_UDPv4); 1856 } 1857 1858 ip->ip_sum = 0; 1859 ip->ip_sum = in_cksum(copym, ip->ip_hl << 2); 1860 (void) looutput(ifp, copym, sintosa(dst), NULL); 1861 } 1862 } 1863