1 /* 2 * Copyright (c) 1982, 1986, 1988, 1990, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 4. Neither the name of the University nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * @(#)ip_output.c 8.3 (Berkeley) 1/21/94 30 * $FreeBSD$ 31 */ 32 33 #include "opt_ipfw.h" 34 #include "opt_ipsec.h" 35 #include "opt_mac.h" 36 #include "opt_mbuf_stress_test.h" 37 38 #include <sys/param.h> 39 #include <sys/systm.h> 40 #include <sys/kernel.h> 41 #include <sys/mac.h> 42 #include <sys/malloc.h> 43 #include <sys/mbuf.h> 44 #include <sys/protosw.h> 45 #include <sys/socket.h> 46 #include <sys/socketvar.h> 47 #include <sys/sysctl.h> 48 49 #include <net/if.h> 50 #include <net/netisr.h> 51 #include <net/pfil.h> 52 #include <net/route.h> 53 54 #include <netinet/in.h> 55 #include <netinet/in_systm.h> 56 #include <netinet/ip.h> 57 #include <netinet/in_pcb.h> 58 #include <netinet/in_var.h> 59 #include <netinet/ip_var.h> 60 61 62 #include <machine/in_cksum.h> 63 64 static MALLOC_DEFINE(M_IPMOPTS, "ip_moptions", "internet multicast options"); 65 66 #ifdef IPSEC 67 #include <netinet6/ipsec.h> 68 #include <netkey/key.h> 69 #ifdef IPSEC_DEBUG 70 #include <netkey/key_debug.h> 71 #else 72 #define KEYDEBUG(lev,arg) 73 #endif 74 #endif /*IPSEC*/ 75 76 #ifdef FAST_IPSEC 77 #include <netipsec/ipsec.h> 78 #include <netipsec/xform.h> 79 #include <netipsec/key.h> 80 #endif /*FAST_IPSEC*/ 81 82 #define print_ip(x, a, y) printf("%s %d.%d.%d.%d%s",\ 83 x, (ntohl(a.s_addr)>>24)&0xFF,\ 84 (ntohl(a.s_addr)>>16)&0xFF,\ 85 (ntohl(a.s_addr)>>8)&0xFF,\ 86 (ntohl(a.s_addr))&0xFF, y); 87 88 u_short ip_id; 89 90 #ifdef MBUF_STRESS_TEST 91 int mbuf_frag_size = 0; 92 SYSCTL_INT(_net_inet_ip, OID_AUTO, mbuf_frag_size, CTLFLAG_RW, 93 &mbuf_frag_size, 0, "Fragment outgoing mbufs to this size"); 94 #endif 95 96 static struct mbuf *ip_insertoptions(struct mbuf *, struct mbuf *, int *); 97 static struct ifnet *ip_multicast_if(struct in_addr *, int *); 98 static void ip_mloopback 99 (struct ifnet *, struct mbuf *, struct sockaddr_in *, int); 100 static int ip_getmoptions 101 (struct sockopt *, struct ip_moptions *); 102 static int ip_pcbopts(int, struct mbuf **, struct mbuf *); 103 static int ip_setmoptions 104 (struct sockopt *, struct ip_moptions **); 105 106 int ip_optcopy(struct ip *, struct ip *); 107 108 109 extern struct protosw inetsw[]; 110 111 /* 112 * IP output. The packet in mbuf chain m contains a skeletal IP 113 * header (with len, off, ttl, proto, tos, src, dst). 114 * The mbuf chain containing the packet will be freed. 115 * The mbuf opt, if present, will not be freed. 116 * In the IP forwarding case, the packet will arrive with options already 117 * inserted, so must have a NULL opt pointer. 118 */ 119 int 120 ip_output(struct mbuf *m, struct mbuf *opt, struct route *ro, 121 int flags, struct ip_moptions *imo, struct inpcb *inp) 122 { 123 struct ip *ip; 124 struct ifnet *ifp = NULL; /* keep compiler happy */ 125 struct mbuf *m0; 126 int hlen = sizeof (struct ip); 127 int len, error = 0; 128 struct sockaddr_in *dst = NULL; /* keep compiler happy */ 129 struct in_ifaddr *ia = NULL; 130 int isbroadcast, sw_csum; 131 struct route iproute; 132 struct in_addr odst; 133 #ifdef IPFIREWALL_FORWARD 134 struct m_tag *fwd_tag = NULL; 135 #endif 136 #ifdef IPSEC 137 struct secpolicy *sp = NULL; 138 #endif 139 #ifdef FAST_IPSEC 140 struct secpolicy *sp = NULL; 141 struct tdb_ident *tdbi; 142 struct m_tag *mtag; 143 int s; 144 #endif /* FAST_IPSEC */ 145 146 M_ASSERTPKTHDR(m); 147 148 if (ro == NULL) { 149 ro = &iproute; 150 bzero(ro, sizeof (*ro)); 151 } 152 153 if (inp != NULL) 154 INP_LOCK_ASSERT(inp); 155 156 if (opt) { 157 len = 0; 158 m = ip_insertoptions(m, opt, &len); 159 if (len != 0) 160 hlen = len; 161 } 162 ip = mtod(m, struct ip *); 163 164 /* 165 * Fill in IP header. If we are not allowing fragmentation, 166 * then the ip_id field is meaningless, but we don't set it 167 * to zero. Doing so causes various problems when devices along 168 * the path (routers, load balancers, firewalls, etc.) illegally 169 * disable DF on our packet. Note that a 16-bit counter 170 * will wrap around in less than 10 seconds at 100 Mbit/s on a 171 * medium with MTU 1500. See Steven M. Bellovin, "A Technique 172 * for Counting NATted Hosts", Proc. IMW'02, available at 173 * <http://www.research.att.com/~smb/papers/fnat.pdf>. 174 */ 175 if ((flags & (IP_FORWARDING|IP_RAWOUTPUT)) == 0) { 176 ip->ip_v = IPVERSION; 177 ip->ip_hl = hlen >> 2; 178 ip->ip_id = ip_newid(); 179 ipstat.ips_localout++; 180 } else { 181 hlen = ip->ip_hl << 2; 182 } 183 184 dst = (struct sockaddr_in *)&ro->ro_dst; 185 again: 186 /* 187 * If there is a cached route, 188 * check that it is to the same destination 189 * and is still up. If not, free it and try again. 190 * The address family should also be checked in case of sharing the 191 * cache with IPv6. 192 */ 193 if (ro->ro_rt && ((ro->ro_rt->rt_flags & RTF_UP) == 0 || 194 dst->sin_family != AF_INET || 195 dst->sin_addr.s_addr != ip->ip_dst.s_addr)) { 196 RTFREE(ro->ro_rt); 197 ro->ro_rt = (struct rtentry *)0; 198 } 199 #ifdef IPFIREWALL_FORWARD 200 if (ro->ro_rt == NULL && fwd_tag == NULL) { 201 #else 202 if (ro->ro_rt == NULL) { 203 #endif 204 bzero(dst, sizeof(*dst)); 205 dst->sin_family = AF_INET; 206 dst->sin_len = sizeof(*dst); 207 dst->sin_addr = ip->ip_dst; 208 } 209 /* 210 * If routing to interface only, 211 * short circuit routing lookup. 212 */ 213 if (flags & IP_ROUTETOIF) { 214 if ((ia = ifatoia(ifa_ifwithdstaddr(sintosa(dst)))) == NULL && 215 (ia = ifatoia(ifa_ifwithnet(sintosa(dst)))) == NULL) { 216 ipstat.ips_noroute++; 217 error = ENETUNREACH; 218 goto bad; 219 } 220 ifp = ia->ia_ifp; 221 ip->ip_ttl = 1; 222 isbroadcast = in_broadcast(dst->sin_addr, ifp); 223 } else if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) && 224 imo != NULL && imo->imo_multicast_ifp != NULL) { 225 /* 226 * Bypass the normal routing lookup for multicast 227 * packets if the interface is specified. 228 */ 229 ifp = imo->imo_multicast_ifp; 230 IFP_TO_IA(ifp, ia); 231 isbroadcast = 0; /* fool gcc */ 232 } else { 233 /* 234 * We want to do any cloning requested by the link layer, 235 * as this is probably required in all cases for correct 236 * operation (as it is for ARP). 237 */ 238 if (ro->ro_rt == NULL) 239 rtalloc_ign(ro, 0); 240 if (ro->ro_rt == NULL) { 241 ipstat.ips_noroute++; 242 error = EHOSTUNREACH; 243 goto bad; 244 } 245 ia = ifatoia(ro->ro_rt->rt_ifa); 246 ifp = ro->ro_rt->rt_ifp; 247 ro->ro_rt->rt_rmx.rmx_pksent++; 248 if (ro->ro_rt->rt_flags & RTF_GATEWAY) 249 dst = (struct sockaddr_in *)ro->ro_rt->rt_gateway; 250 if (ro->ro_rt->rt_flags & RTF_HOST) 251 isbroadcast = (ro->ro_rt->rt_flags & RTF_BROADCAST); 252 else 253 isbroadcast = in_broadcast(dst->sin_addr, ifp); 254 } 255 if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr))) { 256 struct in_multi *inm; 257 258 m->m_flags |= M_MCAST; 259 /* 260 * IP destination address is multicast. Make sure "dst" 261 * still points to the address in "ro". (It may have been 262 * changed to point to a gateway address, above.) 263 */ 264 dst = (struct sockaddr_in *)&ro->ro_dst; 265 /* 266 * See if the caller provided any multicast options 267 */ 268 if (imo != NULL) { 269 ip->ip_ttl = imo->imo_multicast_ttl; 270 if (imo->imo_multicast_vif != -1) 271 ip->ip_src.s_addr = 272 ip_mcast_src ? 273 ip_mcast_src(imo->imo_multicast_vif) : 274 INADDR_ANY; 275 } else 276 ip->ip_ttl = IP_DEFAULT_MULTICAST_TTL; 277 /* 278 * Confirm that the outgoing interface supports multicast. 279 */ 280 if ((imo == NULL) || (imo->imo_multicast_vif == -1)) { 281 if ((ifp->if_flags & IFF_MULTICAST) == 0) { 282 ipstat.ips_noroute++; 283 error = ENETUNREACH; 284 goto bad; 285 } 286 } 287 /* 288 * If source address not specified yet, use address 289 * of outgoing interface. 290 */ 291 if (ip->ip_src.s_addr == INADDR_ANY) { 292 /* Interface may have no addresses. */ 293 if (ia != NULL) 294 ip->ip_src = IA_SIN(ia)->sin_addr; 295 } 296 297 IN_LOOKUP_MULTI(ip->ip_dst, ifp, inm); 298 if (inm != NULL && 299 (imo == NULL || imo->imo_multicast_loop)) { 300 /* 301 * If we belong to the destination multicast group 302 * on the outgoing interface, and the caller did not 303 * forbid loopback, loop back a copy. 304 */ 305 ip_mloopback(ifp, m, dst, hlen); 306 } 307 else { 308 /* 309 * If we are acting as a multicast router, perform 310 * multicast forwarding as if the packet had just 311 * arrived on the interface to which we are about 312 * to send. The multicast forwarding function 313 * recursively calls this function, using the 314 * IP_FORWARDING flag to prevent infinite recursion. 315 * 316 * Multicasts that are looped back by ip_mloopback(), 317 * above, will be forwarded by the ip_input() routine, 318 * if necessary. 319 */ 320 if (ip_mrouter && (flags & IP_FORWARDING) == 0) { 321 /* 322 * If rsvp daemon is not running, do not 323 * set ip_moptions. This ensures that the packet 324 * is multicast and not just sent down one link 325 * as prescribed by rsvpd. 326 */ 327 if (!rsvp_on) 328 imo = NULL; 329 if (ip_mforward && 330 ip_mforward(ip, ifp, m, imo) != 0) { 331 m_freem(m); 332 goto done; 333 } 334 } 335 } 336 337 /* 338 * Multicasts with a time-to-live of zero may be looped- 339 * back, above, but must not be transmitted on a network. 340 * Also, multicasts addressed to the loopback interface 341 * are not sent -- the above call to ip_mloopback() will 342 * loop back a copy if this host actually belongs to the 343 * destination group on the loopback interface. 344 */ 345 if (ip->ip_ttl == 0 || ifp->if_flags & IFF_LOOPBACK) { 346 m_freem(m); 347 goto done; 348 } 349 350 goto sendit; 351 } 352 #ifndef notdef 353 /* 354 * If the source address is not specified yet, use the address 355 * of the outoing interface. In case, keep note we did that, so 356 * if the the firewall changes the next-hop causing the output 357 * interface to change, we can fix that. 358 */ 359 if (ip->ip_src.s_addr == INADDR_ANY) { 360 /* Interface may have no addresses. */ 361 if (ia != NULL) { 362 ip->ip_src = IA_SIN(ia)->sin_addr; 363 } 364 } 365 #endif /* notdef */ 366 /* 367 * Verify that we have any chance at all of being able to queue the 368 * packet or packet fragments, unless ALTQ is enabled on the given 369 * interface in which case packetdrop should be done by queueing. 370 */ 371 #ifdef ALTQ 372 if ((!ALTQ_IS_ENABLED(&ifp->if_snd)) && 373 ((ifp->if_snd.ifq_len + ip->ip_len / ifp->if_mtu + 1) >= 374 ifp->if_snd.ifq_maxlen)) 375 #else 376 if ((ifp->if_snd.ifq_len + ip->ip_len / ifp->if_mtu + 1) >= 377 ifp->if_snd.ifq_maxlen) 378 #endif /* ALTQ */ 379 { 380 error = ENOBUFS; 381 ipstat.ips_odropped++; 382 goto bad; 383 } 384 385 /* 386 * Look for broadcast address and 387 * verify user is allowed to send 388 * such a packet. 389 */ 390 if (isbroadcast) { 391 if ((ifp->if_flags & IFF_BROADCAST) == 0) { 392 error = EADDRNOTAVAIL; 393 goto bad; 394 } 395 if ((flags & IP_ALLOWBROADCAST) == 0) { 396 error = EACCES; 397 goto bad; 398 } 399 /* don't allow broadcast messages to be fragmented */ 400 if (ip->ip_len > ifp->if_mtu) { 401 error = EMSGSIZE; 402 goto bad; 403 } 404 if (flags & IP_SENDONES) 405 ip->ip_dst.s_addr = INADDR_BROADCAST; 406 m->m_flags |= M_BCAST; 407 } else { 408 m->m_flags &= ~M_BCAST; 409 } 410 411 sendit: 412 #ifdef IPSEC 413 /* get SP for this packet */ 414 if (inp == NULL) 415 sp = ipsec4_getpolicybyaddr(m, IPSEC_DIR_OUTBOUND, 416 flags, &error); 417 else 418 sp = ipsec4_getpolicybypcb(m, IPSEC_DIR_OUTBOUND, inp, &error); 419 420 if (sp == NULL) { 421 ipsecstat.out_inval++; 422 goto bad; 423 } 424 425 error = 0; 426 427 /* check policy */ 428 switch (sp->policy) { 429 case IPSEC_POLICY_DISCARD: 430 /* 431 * This packet is just discarded. 432 */ 433 ipsecstat.out_polvio++; 434 goto bad; 435 436 case IPSEC_POLICY_BYPASS: 437 case IPSEC_POLICY_NONE: 438 case IPSEC_POLICY_TCP: 439 /* no need to do IPsec. */ 440 goto skip_ipsec; 441 442 case IPSEC_POLICY_IPSEC: 443 if (sp->req == NULL) { 444 /* acquire a policy */ 445 error = key_spdacquire(sp); 446 goto bad; 447 } 448 break; 449 450 case IPSEC_POLICY_ENTRUST: 451 default: 452 printf("ip_output: Invalid policy found. %d\n", sp->policy); 453 } 454 { 455 struct ipsec_output_state state; 456 bzero(&state, sizeof(state)); 457 state.m = m; 458 if (flags & IP_ROUTETOIF) { 459 state.ro = &iproute; 460 bzero(&iproute, sizeof(iproute)); 461 } else 462 state.ro = ro; 463 state.dst = (struct sockaddr *)dst; 464 465 ip->ip_sum = 0; 466 467 /* 468 * XXX 469 * delayed checksums are not currently compatible with IPsec 470 */ 471 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) { 472 in_delayed_cksum(m); 473 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA; 474 } 475 476 ip->ip_len = htons(ip->ip_len); 477 ip->ip_off = htons(ip->ip_off); 478 479 error = ipsec4_output(&state, sp, flags); 480 481 m = state.m; 482 if (flags & IP_ROUTETOIF) { 483 /* 484 * if we have tunnel mode SA, we may need to ignore 485 * IP_ROUTETOIF. 486 */ 487 if (state.ro != &iproute || state.ro->ro_rt != NULL) { 488 flags &= ~IP_ROUTETOIF; 489 ro = state.ro; 490 } 491 } else 492 ro = state.ro; 493 dst = (struct sockaddr_in *)state.dst; 494 if (error) { 495 /* mbuf is already reclaimed in ipsec4_output. */ 496 m = NULL; 497 switch (error) { 498 case EHOSTUNREACH: 499 case ENETUNREACH: 500 case EMSGSIZE: 501 case ENOBUFS: 502 case ENOMEM: 503 break; 504 default: 505 printf("ip4_output (ipsec): error code %d\n", error); 506 /*fall through*/ 507 case ENOENT: 508 /* don't show these error codes to the user */ 509 error = 0; 510 break; 511 } 512 goto bad; 513 } 514 515 /* be sure to update variables that are affected by ipsec4_output() */ 516 ip = mtod(m, struct ip *); 517 hlen = ip->ip_hl << 2; 518 if (ro->ro_rt == NULL) { 519 if ((flags & IP_ROUTETOIF) == 0) { 520 printf("ip_output: " 521 "can't update route after IPsec processing\n"); 522 error = EHOSTUNREACH; /*XXX*/ 523 goto bad; 524 } 525 } else { 526 if (state.encap) { 527 ia = ifatoia(ro->ro_rt->rt_ifa); 528 ifp = ro->ro_rt->rt_ifp; 529 } 530 } 531 } 532 533 /* make it flipped, again. */ 534 ip->ip_len = ntohs(ip->ip_len); 535 ip->ip_off = ntohs(ip->ip_off); 536 skip_ipsec: 537 #endif /*IPSEC*/ 538 #ifdef FAST_IPSEC 539 /* 540 * Check the security policy (SP) for the packet and, if 541 * required, do IPsec-related processing. There are two 542 * cases here; the first time a packet is sent through 543 * it will be untagged and handled by ipsec4_checkpolicy. 544 * If the packet is resubmitted to ip_output (e.g. after 545 * AH, ESP, etc. processing), there will be a tag to bypass 546 * the lookup and related policy checking. 547 */ 548 mtag = m_tag_find(m, PACKET_TAG_IPSEC_PENDING_TDB, NULL); 549 s = splnet(); 550 if (mtag != NULL) { 551 tdbi = (struct tdb_ident *)(mtag + 1); 552 sp = ipsec_getpolicy(tdbi, IPSEC_DIR_OUTBOUND); 553 if (sp == NULL) 554 error = -EINVAL; /* force silent drop */ 555 m_tag_delete(m, mtag); 556 } else { 557 sp = ipsec4_checkpolicy(m, IPSEC_DIR_OUTBOUND, flags, 558 &error, inp); 559 } 560 /* 561 * There are four return cases: 562 * sp != NULL apply IPsec policy 563 * sp == NULL, error == 0 no IPsec handling needed 564 * sp == NULL, error == -EINVAL discard packet w/o error 565 * sp == NULL, error != 0 discard packet, report error 566 */ 567 if (sp != NULL) { 568 /* Loop detection, check if ipsec processing already done */ 569 KASSERT(sp->req != NULL, ("ip_output: no ipsec request")); 570 for (mtag = m_tag_first(m); mtag != NULL; 571 mtag = m_tag_next(m, mtag)) { 572 if (mtag->m_tag_cookie != MTAG_ABI_COMPAT) 573 continue; 574 if (mtag->m_tag_id != PACKET_TAG_IPSEC_OUT_DONE && 575 mtag->m_tag_id != PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED) 576 continue; 577 /* 578 * Check if policy has an SA associated with it. 579 * This can happen when an SP has yet to acquire 580 * an SA; e.g. on first reference. If it occurs, 581 * then we let ipsec4_process_packet do its thing. 582 */ 583 if (sp->req->sav == NULL) 584 break; 585 tdbi = (struct tdb_ident *)(mtag + 1); 586 if (tdbi->spi == sp->req->sav->spi && 587 tdbi->proto == sp->req->sav->sah->saidx.proto && 588 bcmp(&tdbi->dst, &sp->req->sav->sah->saidx.dst, 589 sizeof (union sockaddr_union)) == 0) { 590 /* 591 * No IPsec processing is needed, free 592 * reference to SP. 593 * 594 * NB: null pointer to avoid free at 595 * done: below. 596 */ 597 KEY_FREESP(&sp), sp = NULL; 598 splx(s); 599 goto spd_done; 600 } 601 } 602 603 /* 604 * Do delayed checksums now because we send before 605 * this is done in the normal processing path. 606 */ 607 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) { 608 in_delayed_cksum(m); 609 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA; 610 } 611 612 ip->ip_len = htons(ip->ip_len); 613 ip->ip_off = htons(ip->ip_off); 614 615 /* NB: callee frees mbuf */ 616 error = ipsec4_process_packet(m, sp->req, flags, 0); 617 /* 618 * Preserve KAME behaviour: ENOENT can be returned 619 * when an SA acquire is in progress. Don't propagate 620 * this to user-level; it confuses applications. 621 * 622 * XXX this will go away when the SADB is redone. 623 */ 624 if (error == ENOENT) 625 error = 0; 626 splx(s); 627 goto done; 628 } else { 629 splx(s); 630 631 if (error != 0) { 632 /* 633 * Hack: -EINVAL is used to signal that a packet 634 * should be silently discarded. This is typically 635 * because we asked key management for an SA and 636 * it was delayed (e.g. kicked up to IKE). 637 */ 638 if (error == -EINVAL) 639 error = 0; 640 goto bad; 641 } else { 642 /* No IPsec processing for this packet. */ 643 } 644 #ifdef notyet 645 /* 646 * If deferred crypto processing is needed, check that 647 * the interface supports it. 648 */ 649 mtag = m_tag_find(m, PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED, NULL); 650 if (mtag != NULL && (ifp->if_capenable & IFCAP_IPSEC) == 0) { 651 /* notify IPsec to do its own crypto */ 652 ipsp_skipcrypto_unmark((struct tdb_ident *)(mtag + 1)); 653 error = EHOSTUNREACH; 654 goto bad; 655 } 656 #endif 657 } 658 spd_done: 659 #endif /* FAST_IPSEC */ 660 661 /* Jump over all PFIL processing if hooks are not active. */ 662 if (inet_pfil_hook.ph_busy_count == -1) 663 goto passout; 664 665 /* Run through list of hooks for output packets. */ 666 odst.s_addr = ip->ip_dst.s_addr; 667 error = pfil_run_hooks(&inet_pfil_hook, &m, ifp, PFIL_OUT); 668 if (error != 0 || m == NULL) 669 goto done; 670 671 ip = mtod(m, struct ip *); 672 673 /* See if destination IP address was changed by packet filter. */ 674 if (odst.s_addr != ip->ip_dst.s_addr) { 675 m->m_flags |= M_SKIP_FIREWALL; 676 if (in_localip(ip->ip_dst)) { 677 m->m_flags |= M_FASTFWD_OURS; 678 if (m->m_pkthdr.rcvif == NULL) 679 m->m_pkthdr.rcvif = loif; 680 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) { 681 m->m_pkthdr.csum_flags |= 682 CSUM_DATA_VALID | CSUM_PSEUDO_HDR; 683 m->m_pkthdr.csum_data = 0xffff; 684 } 685 m->m_pkthdr.csum_flags |= 686 CSUM_IP_CHECKED | CSUM_IP_VALID; 687 688 error = netisr_queue(NETISR_IP, m); 689 goto done; 690 } else 691 goto again; 692 } 693 694 #ifdef IPFIREWALL_FORWARD 695 /* See if local, if yes, send it to netisr with IP_FASTFWD_OURS. */ 696 if (m->m_flags & M_FASTFWD_OURS) { 697 if (m->m_pkthdr.rcvif == NULL) 698 m->m_pkthdr.rcvif = loif; 699 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) { 700 m->m_pkthdr.csum_flags |= 701 CSUM_DATA_VALID | CSUM_PSEUDO_HDR; 702 m->m_pkthdr.csum_data = 0xffff; 703 } 704 m->m_pkthdr.csum_flags |= 705 CSUM_IP_CHECKED | CSUM_IP_VALID; 706 707 error = netisr_queue(NETISR_IP, m); 708 goto done; 709 } 710 /* Or forward to some other address? */ 711 fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL); 712 if (fwd_tag) { 713 if (!in_localip(ip->ip_src) && !in_localaddr(ip->ip_dst)) { 714 dst = (struct sockaddr_in *)&ro->ro_dst; 715 bcopy((fwd_tag+1), dst, sizeof(struct sockaddr_in)); 716 m->m_flags |= M_SKIP_FIREWALL; 717 m_tag_delete(m, fwd_tag); 718 goto again; 719 } else { 720 m_tag_delete(m, fwd_tag); 721 /* Continue. */ 722 } 723 } 724 #endif 725 726 passout: 727 /* 127/8 must not appear on wire - RFC1122. */ 728 if ((ntohl(ip->ip_dst.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET || 729 (ntohl(ip->ip_src.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET) { 730 if ((ifp->if_flags & IFF_LOOPBACK) == 0) { 731 ipstat.ips_badaddr++; 732 error = EADDRNOTAVAIL; 733 goto bad; 734 } 735 } 736 737 m->m_pkthdr.csum_flags |= CSUM_IP; 738 sw_csum = m->m_pkthdr.csum_flags & ~ifp->if_hwassist; 739 if (sw_csum & CSUM_DELAY_DATA) { 740 in_delayed_cksum(m); 741 sw_csum &= ~CSUM_DELAY_DATA; 742 } 743 m->m_pkthdr.csum_flags &= ifp->if_hwassist; 744 745 /* 746 * If small enough for interface, or the interface will take 747 * care of the fragmentation for us, can just send directly. 748 */ 749 if (ip->ip_len <= ifp->if_mtu || (ifp->if_hwassist & CSUM_FRAGMENT && 750 ((ip->ip_off & IP_DF) == 0))) { 751 ip->ip_len = htons(ip->ip_len); 752 ip->ip_off = htons(ip->ip_off); 753 ip->ip_sum = 0; 754 if (sw_csum & CSUM_DELAY_IP) 755 ip->ip_sum = in_cksum(m, hlen); 756 757 /* Record statistics for this interface address. */ 758 if (!(flags & IP_FORWARDING) && ia) { 759 ia->ia_ifa.if_opackets++; 760 ia->ia_ifa.if_obytes += m->m_pkthdr.len; 761 } 762 763 #ifdef IPSEC 764 /* clean ipsec history once it goes out of the node */ 765 ipsec_delaux(m); 766 #endif 767 768 #ifdef MBUF_STRESS_TEST 769 if (mbuf_frag_size && m->m_pkthdr.len > mbuf_frag_size) 770 m = m_fragment(m, M_DONTWAIT, mbuf_frag_size); 771 #endif 772 error = (*ifp->if_output)(ifp, m, 773 (struct sockaddr *)dst, ro->ro_rt); 774 goto done; 775 } 776 777 if (ip->ip_off & IP_DF) { 778 error = EMSGSIZE; 779 /* 780 * This case can happen if the user changed the MTU 781 * of an interface after enabling IP on it. Because 782 * most netifs don't keep track of routes pointing to 783 * them, there is no way for one to update all its 784 * routes when the MTU is changed. 785 */ 786 if ((ro->ro_rt->rt_flags & (RTF_UP | RTF_HOST)) && 787 (ro->ro_rt->rt_rmx.rmx_mtu > ifp->if_mtu)) { 788 ro->ro_rt->rt_rmx.rmx_mtu = ifp->if_mtu; 789 } 790 ipstat.ips_cantfrag++; 791 goto bad; 792 } 793 794 /* 795 * Too large for interface; fragment if possible. If successful, 796 * on return, m will point to a list of packets to be sent. 797 */ 798 error = ip_fragment(ip, &m, ifp->if_mtu, ifp->if_hwassist, sw_csum); 799 if (error) 800 goto bad; 801 for (; m; m = m0) { 802 m0 = m->m_nextpkt; 803 m->m_nextpkt = 0; 804 #ifdef IPSEC 805 /* clean ipsec history once it goes out of the node */ 806 ipsec_delaux(m); 807 #endif 808 if (error == 0) { 809 /* Record statistics for this interface address. */ 810 if (ia != NULL) { 811 ia->ia_ifa.if_opackets++; 812 ia->ia_ifa.if_obytes += m->m_pkthdr.len; 813 } 814 815 error = (*ifp->if_output)(ifp, m, 816 (struct sockaddr *)dst, ro->ro_rt); 817 } else 818 m_freem(m); 819 } 820 821 if (error == 0) 822 ipstat.ips_fragmented++; 823 824 done: 825 if (ro == &iproute && ro->ro_rt) { 826 RTFREE(ro->ro_rt); 827 } 828 #ifdef IPSEC 829 if (sp != NULL) { 830 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 831 printf("DP ip_output call free SP:%p\n", sp)); 832 key_freesp(sp); 833 } 834 #endif 835 #ifdef FAST_IPSEC 836 if (sp != NULL) 837 KEY_FREESP(&sp); 838 #endif 839 return (error); 840 bad: 841 m_freem(m); 842 goto done; 843 } 844 845 /* 846 * Create a chain of fragments which fit the given mtu. m_frag points to the 847 * mbuf to be fragmented; on return it points to the chain with the fragments. 848 * Return 0 if no error. If error, m_frag may contain a partially built 849 * chain of fragments that should be freed by the caller. 850 * 851 * if_hwassist_flags is the hw offload capabilities (see if_data.ifi_hwassist) 852 * sw_csum contains the delayed checksums flags (e.g., CSUM_DELAY_IP). 853 */ 854 int 855 ip_fragment(struct ip *ip, struct mbuf **m_frag, int mtu, 856 u_long if_hwassist_flags, int sw_csum) 857 { 858 int error = 0; 859 int hlen = ip->ip_hl << 2; 860 int len = (mtu - hlen) & ~7; /* size of payload in each fragment */ 861 int off; 862 struct mbuf *m0 = *m_frag; /* the original packet */ 863 int firstlen; 864 struct mbuf **mnext; 865 int nfrags; 866 867 if (ip->ip_off & IP_DF) { /* Fragmentation not allowed */ 868 ipstat.ips_cantfrag++; 869 return EMSGSIZE; 870 } 871 872 /* 873 * Must be able to put at least 8 bytes per fragment. 874 */ 875 if (len < 8) 876 return EMSGSIZE; 877 878 /* 879 * If the interface will not calculate checksums on 880 * fragmented packets, then do it here. 881 */ 882 if (m0->m_pkthdr.csum_flags & CSUM_DELAY_DATA && 883 (if_hwassist_flags & CSUM_IP_FRAGS) == 0) { 884 in_delayed_cksum(m0); 885 m0->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA; 886 } 887 888 if (len > PAGE_SIZE) { 889 /* 890 * Fragment large datagrams such that each segment 891 * contains a multiple of PAGE_SIZE amount of data, 892 * plus headers. This enables a receiver to perform 893 * page-flipping zero-copy optimizations. 894 * 895 * XXX When does this help given that sender and receiver 896 * could have different page sizes, and also mtu could 897 * be less than the receiver's page size ? 898 */ 899 int newlen; 900 struct mbuf *m; 901 902 for (m = m0, off = 0; m && (off+m->m_len) <= mtu; m = m->m_next) 903 off += m->m_len; 904 905 /* 906 * firstlen (off - hlen) must be aligned on an 907 * 8-byte boundary 908 */ 909 if (off < hlen) 910 goto smart_frag_failure; 911 off = ((off - hlen) & ~7) + hlen; 912 newlen = (~PAGE_MASK) & mtu; 913 if ((newlen + sizeof (struct ip)) > mtu) { 914 /* we failed, go back the default */ 915 smart_frag_failure: 916 newlen = len; 917 off = hlen + len; 918 } 919 len = newlen; 920 921 } else { 922 off = hlen + len; 923 } 924 925 firstlen = off - hlen; 926 mnext = &m0->m_nextpkt; /* pointer to next packet */ 927 928 /* 929 * Loop through length of segment after first fragment, 930 * make new header and copy data of each part and link onto chain. 931 * Here, m0 is the original packet, m is the fragment being created. 932 * The fragments are linked off the m_nextpkt of the original 933 * packet, which after processing serves as the first fragment. 934 */ 935 for (nfrags = 1; off < ip->ip_len; off += len, nfrags++) { 936 struct ip *mhip; /* ip header on the fragment */ 937 struct mbuf *m; 938 int mhlen = sizeof (struct ip); 939 940 MGETHDR(m, M_DONTWAIT, MT_HEADER); 941 if (m == NULL) { 942 error = ENOBUFS; 943 ipstat.ips_odropped++; 944 goto done; 945 } 946 m->m_flags |= (m0->m_flags & M_MCAST) | M_FRAG; 947 /* 948 * In the first mbuf, leave room for the link header, then 949 * copy the original IP header including options. The payload 950 * goes into an additional mbuf chain returned by m_copy(). 951 */ 952 m->m_data += max_linkhdr; 953 mhip = mtod(m, struct ip *); 954 *mhip = *ip; 955 if (hlen > sizeof (struct ip)) { 956 mhlen = ip_optcopy(ip, mhip) + sizeof (struct ip); 957 mhip->ip_v = IPVERSION; 958 mhip->ip_hl = mhlen >> 2; 959 } 960 m->m_len = mhlen; 961 /* XXX do we need to add ip->ip_off below ? */ 962 mhip->ip_off = ((off - hlen) >> 3) + ip->ip_off; 963 if (off + len >= ip->ip_len) { /* last fragment */ 964 len = ip->ip_len - off; 965 m->m_flags |= M_LASTFRAG; 966 } else 967 mhip->ip_off |= IP_MF; 968 mhip->ip_len = htons((u_short)(len + mhlen)); 969 m->m_next = m_copy(m0, off, len); 970 if (m->m_next == NULL) { /* copy failed */ 971 m_free(m); 972 error = ENOBUFS; /* ??? */ 973 ipstat.ips_odropped++; 974 goto done; 975 } 976 m->m_pkthdr.len = mhlen + len; 977 m->m_pkthdr.rcvif = (struct ifnet *)0; 978 #ifdef MAC 979 mac_create_fragment(m0, m); 980 #endif 981 m->m_pkthdr.csum_flags = m0->m_pkthdr.csum_flags; 982 mhip->ip_off = htons(mhip->ip_off); 983 mhip->ip_sum = 0; 984 if (sw_csum & CSUM_DELAY_IP) 985 mhip->ip_sum = in_cksum(m, mhlen); 986 *mnext = m; 987 mnext = &m->m_nextpkt; 988 } 989 ipstat.ips_ofragments += nfrags; 990 991 /* set first marker for fragment chain */ 992 m0->m_flags |= M_FIRSTFRAG | M_FRAG; 993 m0->m_pkthdr.csum_data = nfrags; 994 995 /* 996 * Update first fragment by trimming what's been copied out 997 * and updating header. 998 */ 999 m_adj(m0, hlen + firstlen - ip->ip_len); 1000 m0->m_pkthdr.len = hlen + firstlen; 1001 ip->ip_len = htons((u_short)m0->m_pkthdr.len); 1002 ip->ip_off |= IP_MF; 1003 ip->ip_off = htons(ip->ip_off); 1004 ip->ip_sum = 0; 1005 if (sw_csum & CSUM_DELAY_IP) 1006 ip->ip_sum = in_cksum(m0, hlen); 1007 1008 done: 1009 *m_frag = m0; 1010 return error; 1011 } 1012 1013 void 1014 in_delayed_cksum(struct mbuf *m) 1015 { 1016 struct ip *ip; 1017 u_short csum, offset; 1018 1019 ip = mtod(m, struct ip *); 1020 offset = ip->ip_hl << 2 ; 1021 csum = in_cksum_skip(m, ip->ip_len, offset); 1022 if (m->m_pkthdr.csum_flags & CSUM_UDP && csum == 0) 1023 csum = 0xffff; 1024 offset += m->m_pkthdr.csum_data; /* checksum offset */ 1025 1026 if (offset + sizeof(u_short) > m->m_len) { 1027 printf("delayed m_pullup, m->len: %d off: %d p: %d\n", 1028 m->m_len, offset, ip->ip_p); 1029 /* 1030 * XXX 1031 * this shouldn't happen, but if it does, the 1032 * correct behavior may be to insert the checksum 1033 * in the existing chain instead of rearranging it. 1034 */ 1035 m = m_pullup(m, offset + sizeof(u_short)); 1036 } 1037 *(u_short *)(m->m_data + offset) = csum; 1038 } 1039 1040 /* 1041 * Insert IP options into preformed packet. 1042 * Adjust IP destination as required for IP source routing, 1043 * as indicated by a non-zero in_addr at the start of the options. 1044 * 1045 * XXX This routine assumes that the packet has no options in place. 1046 */ 1047 static struct mbuf * 1048 ip_insertoptions(m, opt, phlen) 1049 register struct mbuf *m; 1050 struct mbuf *opt; 1051 int *phlen; 1052 { 1053 register struct ipoption *p = mtod(opt, struct ipoption *); 1054 struct mbuf *n; 1055 register struct ip *ip = mtod(m, struct ip *); 1056 unsigned optlen; 1057 1058 optlen = opt->m_len - sizeof(p->ipopt_dst); 1059 if (optlen + ip->ip_len > IP_MAXPACKET) { 1060 *phlen = 0; 1061 return (m); /* XXX should fail */ 1062 } 1063 if (p->ipopt_dst.s_addr) 1064 ip->ip_dst = p->ipopt_dst; 1065 if (m->m_flags & M_EXT || m->m_data - optlen < m->m_pktdat) { 1066 MGETHDR(n, M_DONTWAIT, MT_HEADER); 1067 if (n == NULL) { 1068 *phlen = 0; 1069 return (m); 1070 } 1071 n->m_pkthdr.rcvif = (struct ifnet *)0; 1072 #ifdef MAC 1073 mac_create_mbuf_from_mbuf(m, n); 1074 #endif 1075 n->m_pkthdr.len = m->m_pkthdr.len + optlen; 1076 m->m_len -= sizeof(struct ip); 1077 m->m_data += sizeof(struct ip); 1078 n->m_next = m; 1079 m = n; 1080 m->m_len = optlen + sizeof(struct ip); 1081 m->m_data += max_linkhdr; 1082 bcopy(ip, mtod(m, void *), sizeof(struct ip)); 1083 } else { 1084 m->m_data -= optlen; 1085 m->m_len += optlen; 1086 m->m_pkthdr.len += optlen; 1087 bcopy(ip, mtod(m, void *), sizeof(struct ip)); 1088 } 1089 ip = mtod(m, struct ip *); 1090 bcopy(p->ipopt_list, ip + 1, optlen); 1091 *phlen = sizeof(struct ip) + optlen; 1092 ip->ip_v = IPVERSION; 1093 ip->ip_hl = *phlen >> 2; 1094 ip->ip_len += optlen; 1095 return (m); 1096 } 1097 1098 /* 1099 * Copy options from ip to jp, 1100 * omitting those not copied during fragmentation. 1101 */ 1102 int 1103 ip_optcopy(ip, jp) 1104 struct ip *ip, *jp; 1105 { 1106 register u_char *cp, *dp; 1107 int opt, optlen, cnt; 1108 1109 cp = (u_char *)(ip + 1); 1110 dp = (u_char *)(jp + 1); 1111 cnt = (ip->ip_hl << 2) - sizeof (struct ip); 1112 for (; cnt > 0; cnt -= optlen, cp += optlen) { 1113 opt = cp[0]; 1114 if (opt == IPOPT_EOL) 1115 break; 1116 if (opt == IPOPT_NOP) { 1117 /* Preserve for IP mcast tunnel's LSRR alignment. */ 1118 *dp++ = IPOPT_NOP; 1119 optlen = 1; 1120 continue; 1121 } 1122 1123 KASSERT(cnt >= IPOPT_OLEN + sizeof(*cp), 1124 ("ip_optcopy: malformed ipv4 option")); 1125 optlen = cp[IPOPT_OLEN]; 1126 KASSERT(optlen >= IPOPT_OLEN + sizeof(*cp) && optlen <= cnt, 1127 ("ip_optcopy: malformed ipv4 option")); 1128 1129 /* bogus lengths should have been caught by ip_dooptions */ 1130 if (optlen > cnt) 1131 optlen = cnt; 1132 if (IPOPT_COPIED(opt)) { 1133 bcopy(cp, dp, optlen); 1134 dp += optlen; 1135 } 1136 } 1137 for (optlen = dp - (u_char *)(jp+1); optlen & 0x3; optlen++) 1138 *dp++ = IPOPT_EOL; 1139 return (optlen); 1140 } 1141 1142 /* 1143 * IP socket option processing. 1144 */ 1145 int 1146 ip_ctloutput(so, sopt) 1147 struct socket *so; 1148 struct sockopt *sopt; 1149 { 1150 struct inpcb *inp = sotoinpcb(so); 1151 int error, optval; 1152 1153 error = optval = 0; 1154 if (sopt->sopt_level != IPPROTO_IP) { 1155 return (EINVAL); 1156 } 1157 1158 switch (sopt->sopt_dir) { 1159 case SOPT_SET: 1160 switch (sopt->sopt_name) { 1161 case IP_OPTIONS: 1162 #ifdef notyet 1163 case IP_RETOPTS: 1164 #endif 1165 { 1166 struct mbuf *m; 1167 if (sopt->sopt_valsize > MLEN) { 1168 error = EMSGSIZE; 1169 break; 1170 } 1171 MGET(m, sopt->sopt_td ? M_TRYWAIT : M_DONTWAIT, MT_HEADER); 1172 if (m == NULL) { 1173 error = ENOBUFS; 1174 break; 1175 } 1176 m->m_len = sopt->sopt_valsize; 1177 error = sooptcopyin(sopt, mtod(m, char *), m->m_len, 1178 m->m_len); 1179 1180 return (ip_pcbopts(sopt->sopt_name, &inp->inp_options, 1181 m)); 1182 } 1183 1184 case IP_TOS: 1185 case IP_TTL: 1186 case IP_RECVOPTS: 1187 case IP_RECVRETOPTS: 1188 case IP_RECVDSTADDR: 1189 case IP_RECVTTL: 1190 case IP_RECVIF: 1191 case IP_FAITH: 1192 case IP_ONESBCAST: 1193 error = sooptcopyin(sopt, &optval, sizeof optval, 1194 sizeof optval); 1195 if (error) 1196 break; 1197 1198 switch (sopt->sopt_name) { 1199 case IP_TOS: 1200 inp->inp_ip_tos = optval; 1201 break; 1202 1203 case IP_TTL: 1204 inp->inp_ip_ttl = optval; 1205 break; 1206 #define OPTSET(bit) do { \ 1207 INP_LOCK(inp); \ 1208 if (optval) \ 1209 inp->inp_flags |= bit; \ 1210 else \ 1211 inp->inp_flags &= ~bit; \ 1212 INP_UNLOCK(inp); \ 1213 } while (0) 1214 1215 case IP_RECVOPTS: 1216 OPTSET(INP_RECVOPTS); 1217 break; 1218 1219 case IP_RECVRETOPTS: 1220 OPTSET(INP_RECVRETOPTS); 1221 break; 1222 1223 case IP_RECVDSTADDR: 1224 OPTSET(INP_RECVDSTADDR); 1225 break; 1226 1227 case IP_RECVTTL: 1228 OPTSET(INP_RECVTTL); 1229 break; 1230 1231 case IP_RECVIF: 1232 OPTSET(INP_RECVIF); 1233 break; 1234 1235 case IP_FAITH: 1236 OPTSET(INP_FAITH); 1237 break; 1238 1239 case IP_ONESBCAST: 1240 OPTSET(INP_ONESBCAST); 1241 break; 1242 } 1243 break; 1244 #undef OPTSET 1245 1246 case IP_MULTICAST_IF: 1247 case IP_MULTICAST_VIF: 1248 case IP_MULTICAST_TTL: 1249 case IP_MULTICAST_LOOP: 1250 case IP_ADD_MEMBERSHIP: 1251 case IP_DROP_MEMBERSHIP: 1252 error = ip_setmoptions(sopt, &inp->inp_moptions); 1253 break; 1254 1255 case IP_PORTRANGE: 1256 error = sooptcopyin(sopt, &optval, sizeof optval, 1257 sizeof optval); 1258 if (error) 1259 break; 1260 1261 INP_LOCK(inp); 1262 switch (optval) { 1263 case IP_PORTRANGE_DEFAULT: 1264 inp->inp_flags &= ~(INP_LOWPORT); 1265 inp->inp_flags &= ~(INP_HIGHPORT); 1266 break; 1267 1268 case IP_PORTRANGE_HIGH: 1269 inp->inp_flags &= ~(INP_LOWPORT); 1270 inp->inp_flags |= INP_HIGHPORT; 1271 break; 1272 1273 case IP_PORTRANGE_LOW: 1274 inp->inp_flags &= ~(INP_HIGHPORT); 1275 inp->inp_flags |= INP_LOWPORT; 1276 break; 1277 1278 default: 1279 error = EINVAL; 1280 break; 1281 } 1282 INP_UNLOCK(inp); 1283 break; 1284 1285 #if defined(IPSEC) || defined(FAST_IPSEC) 1286 case IP_IPSEC_POLICY: 1287 { 1288 caddr_t req; 1289 size_t len = 0; 1290 int priv; 1291 struct mbuf *m; 1292 int optname; 1293 1294 if ((error = soopt_getm(sopt, &m)) != 0) /* XXX */ 1295 break; 1296 if ((error = soopt_mcopyin(sopt, m)) != 0) /* XXX */ 1297 break; 1298 priv = (sopt->sopt_td != NULL && 1299 suser(sopt->sopt_td) != 0) ? 0 : 1; 1300 req = mtod(m, caddr_t); 1301 len = m->m_len; 1302 optname = sopt->sopt_name; 1303 error = ipsec4_set_policy(inp, optname, req, len, priv); 1304 m_freem(m); 1305 break; 1306 } 1307 #endif /*IPSEC*/ 1308 1309 default: 1310 error = ENOPROTOOPT; 1311 break; 1312 } 1313 break; 1314 1315 case SOPT_GET: 1316 switch (sopt->sopt_name) { 1317 case IP_OPTIONS: 1318 case IP_RETOPTS: 1319 if (inp->inp_options) 1320 error = sooptcopyout(sopt, 1321 mtod(inp->inp_options, 1322 char *), 1323 inp->inp_options->m_len); 1324 else 1325 sopt->sopt_valsize = 0; 1326 break; 1327 1328 case IP_TOS: 1329 case IP_TTL: 1330 case IP_RECVOPTS: 1331 case IP_RECVRETOPTS: 1332 case IP_RECVDSTADDR: 1333 case IP_RECVTTL: 1334 case IP_RECVIF: 1335 case IP_PORTRANGE: 1336 case IP_FAITH: 1337 case IP_ONESBCAST: 1338 switch (sopt->sopt_name) { 1339 1340 case IP_TOS: 1341 optval = inp->inp_ip_tos; 1342 break; 1343 1344 case IP_TTL: 1345 optval = inp->inp_ip_ttl; 1346 break; 1347 1348 #define OPTBIT(bit) (inp->inp_flags & bit ? 1 : 0) 1349 1350 case IP_RECVOPTS: 1351 optval = OPTBIT(INP_RECVOPTS); 1352 break; 1353 1354 case IP_RECVRETOPTS: 1355 optval = OPTBIT(INP_RECVRETOPTS); 1356 break; 1357 1358 case IP_RECVDSTADDR: 1359 optval = OPTBIT(INP_RECVDSTADDR); 1360 break; 1361 1362 case IP_RECVTTL: 1363 optval = OPTBIT(INP_RECVTTL); 1364 break; 1365 1366 case IP_RECVIF: 1367 optval = OPTBIT(INP_RECVIF); 1368 break; 1369 1370 case IP_PORTRANGE: 1371 if (inp->inp_flags & INP_HIGHPORT) 1372 optval = IP_PORTRANGE_HIGH; 1373 else if (inp->inp_flags & INP_LOWPORT) 1374 optval = IP_PORTRANGE_LOW; 1375 else 1376 optval = 0; 1377 break; 1378 1379 case IP_FAITH: 1380 optval = OPTBIT(INP_FAITH); 1381 break; 1382 1383 case IP_ONESBCAST: 1384 optval = OPTBIT(INP_ONESBCAST); 1385 break; 1386 } 1387 error = sooptcopyout(sopt, &optval, sizeof optval); 1388 break; 1389 1390 case IP_MULTICAST_IF: 1391 case IP_MULTICAST_VIF: 1392 case IP_MULTICAST_TTL: 1393 case IP_MULTICAST_LOOP: 1394 case IP_ADD_MEMBERSHIP: 1395 case IP_DROP_MEMBERSHIP: 1396 error = ip_getmoptions(sopt, inp->inp_moptions); 1397 break; 1398 1399 #if defined(IPSEC) || defined(FAST_IPSEC) 1400 case IP_IPSEC_POLICY: 1401 { 1402 struct mbuf *m = NULL; 1403 caddr_t req = NULL; 1404 size_t len = 0; 1405 1406 if (m != 0) { 1407 req = mtod(m, caddr_t); 1408 len = m->m_len; 1409 } 1410 error = ipsec4_get_policy(sotoinpcb(so), req, len, &m); 1411 if (error == 0) 1412 error = soopt_mcopyout(sopt, m); /* XXX */ 1413 if (error == 0) 1414 m_freem(m); 1415 break; 1416 } 1417 #endif /*IPSEC*/ 1418 1419 default: 1420 error = ENOPROTOOPT; 1421 break; 1422 } 1423 break; 1424 } 1425 return (error); 1426 } 1427 1428 /* 1429 * Set up IP options in pcb for insertion in output packets. 1430 * Store in mbuf with pointer in pcbopt, adding pseudo-option 1431 * with destination address if source routed. 1432 */ 1433 static int 1434 ip_pcbopts(optname, pcbopt, m) 1435 int optname; 1436 struct mbuf **pcbopt; 1437 register struct mbuf *m; 1438 { 1439 register int cnt, optlen; 1440 register u_char *cp; 1441 u_char opt; 1442 1443 /* turn off any old options */ 1444 if (*pcbopt) 1445 (void)m_free(*pcbopt); 1446 *pcbopt = 0; 1447 if (m == (struct mbuf *)0 || m->m_len == 0) { 1448 /* 1449 * Only turning off any previous options. 1450 */ 1451 if (m) 1452 (void)m_free(m); 1453 return (0); 1454 } 1455 1456 if (m->m_len % sizeof(int32_t)) 1457 goto bad; 1458 /* 1459 * IP first-hop destination address will be stored before 1460 * actual options; move other options back 1461 * and clear it when none present. 1462 */ 1463 if (m->m_data + m->m_len + sizeof(struct in_addr) >= &m->m_dat[MLEN]) 1464 goto bad; 1465 cnt = m->m_len; 1466 m->m_len += sizeof(struct in_addr); 1467 cp = mtod(m, u_char *) + sizeof(struct in_addr); 1468 bcopy(mtod(m, void *), cp, (unsigned)cnt); 1469 bzero(mtod(m, void *), sizeof(struct in_addr)); 1470 1471 for (; cnt > 0; cnt -= optlen, cp += optlen) { 1472 opt = cp[IPOPT_OPTVAL]; 1473 if (opt == IPOPT_EOL) 1474 break; 1475 if (opt == IPOPT_NOP) 1476 optlen = 1; 1477 else { 1478 if (cnt < IPOPT_OLEN + sizeof(*cp)) 1479 goto bad; 1480 optlen = cp[IPOPT_OLEN]; 1481 if (optlen < IPOPT_OLEN + sizeof(*cp) || optlen > cnt) 1482 goto bad; 1483 } 1484 switch (opt) { 1485 1486 default: 1487 break; 1488 1489 case IPOPT_LSRR: 1490 case IPOPT_SSRR: 1491 /* 1492 * user process specifies route as: 1493 * ->A->B->C->D 1494 * D must be our final destination (but we can't 1495 * check that since we may not have connected yet). 1496 * A is first hop destination, which doesn't appear in 1497 * actual IP option, but is stored before the options. 1498 */ 1499 if (optlen < IPOPT_MINOFF - 1 + sizeof(struct in_addr)) 1500 goto bad; 1501 m->m_len -= sizeof(struct in_addr); 1502 cnt -= sizeof(struct in_addr); 1503 optlen -= sizeof(struct in_addr); 1504 cp[IPOPT_OLEN] = optlen; 1505 /* 1506 * Move first hop before start of options. 1507 */ 1508 bcopy((caddr_t)&cp[IPOPT_OFFSET+1], mtod(m, caddr_t), 1509 sizeof(struct in_addr)); 1510 /* 1511 * Then copy rest of options back 1512 * to close up the deleted entry. 1513 */ 1514 bcopy((&cp[IPOPT_OFFSET+1] + sizeof(struct in_addr)), 1515 &cp[IPOPT_OFFSET+1], 1516 (unsigned)cnt - (IPOPT_MINOFF - 1)); 1517 break; 1518 } 1519 } 1520 if (m->m_len > MAX_IPOPTLEN + sizeof(struct in_addr)) 1521 goto bad; 1522 *pcbopt = m; 1523 return (0); 1524 1525 bad: 1526 (void)m_free(m); 1527 return (EINVAL); 1528 } 1529 1530 /* 1531 * XXX 1532 * The whole multicast option thing needs to be re-thought. 1533 * Several of these options are equally applicable to non-multicast 1534 * transmission, and one (IP_MULTICAST_TTL) totally duplicates a 1535 * standard option (IP_TTL). 1536 */ 1537 1538 /* 1539 * following RFC1724 section 3.3, 0.0.0.0/8 is interpreted as interface index. 1540 */ 1541 static struct ifnet * 1542 ip_multicast_if(a, ifindexp) 1543 struct in_addr *a; 1544 int *ifindexp; 1545 { 1546 int ifindex; 1547 struct ifnet *ifp; 1548 1549 if (ifindexp) 1550 *ifindexp = 0; 1551 if (ntohl(a->s_addr) >> 24 == 0) { 1552 ifindex = ntohl(a->s_addr) & 0xffffff; 1553 if (ifindex < 0 || if_index < ifindex) 1554 return NULL; 1555 ifp = ifnet_byindex(ifindex); 1556 if (ifindexp) 1557 *ifindexp = ifindex; 1558 } else { 1559 INADDR_TO_IFP(*a, ifp); 1560 } 1561 return ifp; 1562 } 1563 1564 /* 1565 * Set the IP multicast options in response to user setsockopt(). 1566 */ 1567 static int 1568 ip_setmoptions(sopt, imop) 1569 struct sockopt *sopt; 1570 struct ip_moptions **imop; 1571 { 1572 int error = 0; 1573 int i; 1574 struct in_addr addr; 1575 struct ip_mreq mreq; 1576 struct ifnet *ifp; 1577 struct ip_moptions *imo = *imop; 1578 struct route ro; 1579 struct sockaddr_in *dst; 1580 int ifindex; 1581 int s; 1582 1583 if (imo == NULL) { 1584 /* 1585 * No multicast option buffer attached to the pcb; 1586 * allocate one and initialize to default values. 1587 */ 1588 imo = (struct ip_moptions*)malloc(sizeof(*imo), M_IPMOPTS, 1589 M_WAITOK); 1590 1591 if (imo == NULL) 1592 return (ENOBUFS); 1593 *imop = imo; 1594 imo->imo_multicast_ifp = NULL; 1595 imo->imo_multicast_addr.s_addr = INADDR_ANY; 1596 imo->imo_multicast_vif = -1; 1597 imo->imo_multicast_ttl = IP_DEFAULT_MULTICAST_TTL; 1598 imo->imo_multicast_loop = IP_DEFAULT_MULTICAST_LOOP; 1599 imo->imo_num_memberships = 0; 1600 } 1601 1602 switch (sopt->sopt_name) { 1603 /* store an index number for the vif you wanna use in the send */ 1604 case IP_MULTICAST_VIF: 1605 if (legal_vif_num == 0) { 1606 error = EOPNOTSUPP; 1607 break; 1608 } 1609 error = sooptcopyin(sopt, &i, sizeof i, sizeof i); 1610 if (error) 1611 break; 1612 if (!legal_vif_num(i) && (i != -1)) { 1613 error = EINVAL; 1614 break; 1615 } 1616 imo->imo_multicast_vif = i; 1617 break; 1618 1619 case IP_MULTICAST_IF: 1620 /* 1621 * Select the interface for outgoing multicast packets. 1622 */ 1623 error = sooptcopyin(sopt, &addr, sizeof addr, sizeof addr); 1624 if (error) 1625 break; 1626 /* 1627 * INADDR_ANY is used to remove a previous selection. 1628 * When no interface is selected, a default one is 1629 * chosen every time a multicast packet is sent. 1630 */ 1631 if (addr.s_addr == INADDR_ANY) { 1632 imo->imo_multicast_ifp = NULL; 1633 break; 1634 } 1635 /* 1636 * The selected interface is identified by its local 1637 * IP address. Find the interface and confirm that 1638 * it supports multicasting. 1639 */ 1640 s = splimp(); 1641 ifp = ip_multicast_if(&addr, &ifindex); 1642 if (ifp == NULL || (ifp->if_flags & IFF_MULTICAST) == 0) { 1643 splx(s); 1644 error = EADDRNOTAVAIL; 1645 break; 1646 } 1647 imo->imo_multicast_ifp = ifp; 1648 if (ifindex) 1649 imo->imo_multicast_addr = addr; 1650 else 1651 imo->imo_multicast_addr.s_addr = INADDR_ANY; 1652 splx(s); 1653 break; 1654 1655 case IP_MULTICAST_TTL: 1656 /* 1657 * Set the IP time-to-live for outgoing multicast packets. 1658 * The original multicast API required a char argument, 1659 * which is inconsistent with the rest of the socket API. 1660 * We allow either a char or an int. 1661 */ 1662 if (sopt->sopt_valsize == 1) { 1663 u_char ttl; 1664 error = sooptcopyin(sopt, &ttl, 1, 1); 1665 if (error) 1666 break; 1667 imo->imo_multicast_ttl = ttl; 1668 } else { 1669 u_int ttl; 1670 error = sooptcopyin(sopt, &ttl, sizeof ttl, 1671 sizeof ttl); 1672 if (error) 1673 break; 1674 if (ttl > 255) 1675 error = EINVAL; 1676 else 1677 imo->imo_multicast_ttl = ttl; 1678 } 1679 break; 1680 1681 case IP_MULTICAST_LOOP: 1682 /* 1683 * Set the loopback flag for outgoing multicast packets. 1684 * Must be zero or one. The original multicast API required a 1685 * char argument, which is inconsistent with the rest 1686 * of the socket API. We allow either a char or an int. 1687 */ 1688 if (sopt->sopt_valsize == 1) { 1689 u_char loop; 1690 error = sooptcopyin(sopt, &loop, 1, 1); 1691 if (error) 1692 break; 1693 imo->imo_multicast_loop = !!loop; 1694 } else { 1695 u_int loop; 1696 error = sooptcopyin(sopt, &loop, sizeof loop, 1697 sizeof loop); 1698 if (error) 1699 break; 1700 imo->imo_multicast_loop = !!loop; 1701 } 1702 break; 1703 1704 case IP_ADD_MEMBERSHIP: 1705 /* 1706 * Add a multicast group membership. 1707 * Group must be a valid IP multicast address. 1708 */ 1709 error = sooptcopyin(sopt, &mreq, sizeof mreq, sizeof mreq); 1710 if (error) 1711 break; 1712 1713 if (!IN_MULTICAST(ntohl(mreq.imr_multiaddr.s_addr))) { 1714 error = EINVAL; 1715 break; 1716 } 1717 s = splimp(); 1718 /* 1719 * If no interface address was provided, use the interface of 1720 * the route to the given multicast address. 1721 */ 1722 if (mreq.imr_interface.s_addr == INADDR_ANY) { 1723 bzero((caddr_t)&ro, sizeof(ro)); 1724 dst = (struct sockaddr_in *)&ro.ro_dst; 1725 dst->sin_len = sizeof(*dst); 1726 dst->sin_family = AF_INET; 1727 dst->sin_addr = mreq.imr_multiaddr; 1728 rtalloc_ign(&ro, RTF_CLONING); 1729 if (ro.ro_rt == NULL) { 1730 error = EADDRNOTAVAIL; 1731 splx(s); 1732 break; 1733 } 1734 ifp = ro.ro_rt->rt_ifp; 1735 RTFREE(ro.ro_rt); 1736 } 1737 else { 1738 ifp = ip_multicast_if(&mreq.imr_interface, NULL); 1739 } 1740 1741 /* 1742 * See if we found an interface, and confirm that it 1743 * supports multicast. 1744 */ 1745 if (ifp == NULL || (ifp->if_flags & IFF_MULTICAST) == 0) { 1746 error = EADDRNOTAVAIL; 1747 splx(s); 1748 break; 1749 } 1750 /* 1751 * See if the membership already exists or if all the 1752 * membership slots are full. 1753 */ 1754 for (i = 0; i < imo->imo_num_memberships; ++i) { 1755 if (imo->imo_membership[i]->inm_ifp == ifp && 1756 imo->imo_membership[i]->inm_addr.s_addr 1757 == mreq.imr_multiaddr.s_addr) 1758 break; 1759 } 1760 if (i < imo->imo_num_memberships) { 1761 error = EADDRINUSE; 1762 splx(s); 1763 break; 1764 } 1765 if (i == IP_MAX_MEMBERSHIPS) { 1766 error = ETOOMANYREFS; 1767 splx(s); 1768 break; 1769 } 1770 /* 1771 * Everything looks good; add a new record to the multicast 1772 * address list for the given interface. 1773 */ 1774 if ((imo->imo_membership[i] = 1775 in_addmulti(&mreq.imr_multiaddr, ifp)) == NULL) { 1776 error = ENOBUFS; 1777 splx(s); 1778 break; 1779 } 1780 ++imo->imo_num_memberships; 1781 splx(s); 1782 break; 1783 1784 case IP_DROP_MEMBERSHIP: 1785 /* 1786 * Drop a multicast group membership. 1787 * Group must be a valid IP multicast address. 1788 */ 1789 error = sooptcopyin(sopt, &mreq, sizeof mreq, sizeof mreq); 1790 if (error) 1791 break; 1792 1793 if (!IN_MULTICAST(ntohl(mreq.imr_multiaddr.s_addr))) { 1794 error = EINVAL; 1795 break; 1796 } 1797 1798 s = splimp(); 1799 /* 1800 * If an interface address was specified, get a pointer 1801 * to its ifnet structure. 1802 */ 1803 if (mreq.imr_interface.s_addr == INADDR_ANY) 1804 ifp = NULL; 1805 else { 1806 ifp = ip_multicast_if(&mreq.imr_interface, NULL); 1807 if (ifp == NULL) { 1808 error = EADDRNOTAVAIL; 1809 splx(s); 1810 break; 1811 } 1812 } 1813 /* 1814 * Find the membership in the membership array. 1815 */ 1816 for (i = 0; i < imo->imo_num_memberships; ++i) { 1817 if ((ifp == NULL || 1818 imo->imo_membership[i]->inm_ifp == ifp) && 1819 imo->imo_membership[i]->inm_addr.s_addr == 1820 mreq.imr_multiaddr.s_addr) 1821 break; 1822 } 1823 if (i == imo->imo_num_memberships) { 1824 error = EADDRNOTAVAIL; 1825 splx(s); 1826 break; 1827 } 1828 /* 1829 * Give up the multicast address record to which the 1830 * membership points. 1831 */ 1832 in_delmulti(imo->imo_membership[i]); 1833 /* 1834 * Remove the gap in the membership array. 1835 */ 1836 for (++i; i < imo->imo_num_memberships; ++i) 1837 imo->imo_membership[i-1] = imo->imo_membership[i]; 1838 --imo->imo_num_memberships; 1839 splx(s); 1840 break; 1841 1842 default: 1843 error = EOPNOTSUPP; 1844 break; 1845 } 1846 1847 /* 1848 * If all options have default values, no need to keep the mbuf. 1849 */ 1850 if (imo->imo_multicast_ifp == NULL && 1851 imo->imo_multicast_vif == -1 && 1852 imo->imo_multicast_ttl == IP_DEFAULT_MULTICAST_TTL && 1853 imo->imo_multicast_loop == IP_DEFAULT_MULTICAST_LOOP && 1854 imo->imo_num_memberships == 0) { 1855 free(*imop, M_IPMOPTS); 1856 *imop = NULL; 1857 } 1858 1859 return (error); 1860 } 1861 1862 /* 1863 * Return the IP multicast options in response to user getsockopt(). 1864 */ 1865 static int 1866 ip_getmoptions(sopt, imo) 1867 struct sockopt *sopt; 1868 register struct ip_moptions *imo; 1869 { 1870 struct in_addr addr; 1871 struct in_ifaddr *ia; 1872 int error, optval; 1873 u_char coptval; 1874 1875 error = 0; 1876 switch (sopt->sopt_name) { 1877 case IP_MULTICAST_VIF: 1878 if (imo != NULL) 1879 optval = imo->imo_multicast_vif; 1880 else 1881 optval = -1; 1882 error = sooptcopyout(sopt, &optval, sizeof optval); 1883 break; 1884 1885 case IP_MULTICAST_IF: 1886 if (imo == NULL || imo->imo_multicast_ifp == NULL) 1887 addr.s_addr = INADDR_ANY; 1888 else if (imo->imo_multicast_addr.s_addr) { 1889 /* return the value user has set */ 1890 addr = imo->imo_multicast_addr; 1891 } else { 1892 IFP_TO_IA(imo->imo_multicast_ifp, ia); 1893 addr.s_addr = (ia == NULL) ? INADDR_ANY 1894 : IA_SIN(ia)->sin_addr.s_addr; 1895 } 1896 error = sooptcopyout(sopt, &addr, sizeof addr); 1897 break; 1898 1899 case IP_MULTICAST_TTL: 1900 if (imo == 0) 1901 optval = coptval = IP_DEFAULT_MULTICAST_TTL; 1902 else 1903 optval = coptval = imo->imo_multicast_ttl; 1904 if (sopt->sopt_valsize == 1) 1905 error = sooptcopyout(sopt, &coptval, 1); 1906 else 1907 error = sooptcopyout(sopt, &optval, sizeof optval); 1908 break; 1909 1910 case IP_MULTICAST_LOOP: 1911 if (imo == 0) 1912 optval = coptval = IP_DEFAULT_MULTICAST_LOOP; 1913 else 1914 optval = coptval = imo->imo_multicast_loop; 1915 if (sopt->sopt_valsize == 1) 1916 error = sooptcopyout(sopt, &coptval, 1); 1917 else 1918 error = sooptcopyout(sopt, &optval, sizeof optval); 1919 break; 1920 1921 default: 1922 error = ENOPROTOOPT; 1923 break; 1924 } 1925 return (error); 1926 } 1927 1928 /* 1929 * Discard the IP multicast options. 1930 */ 1931 void 1932 ip_freemoptions(imo) 1933 register struct ip_moptions *imo; 1934 { 1935 register int i; 1936 1937 if (imo != NULL) { 1938 for (i = 0; i < imo->imo_num_memberships; ++i) 1939 in_delmulti(imo->imo_membership[i]); 1940 free(imo, M_IPMOPTS); 1941 } 1942 } 1943 1944 /* 1945 * Routine called from ip_output() to loop back a copy of an IP multicast 1946 * packet to the input queue of a specified interface. Note that this 1947 * calls the output routine of the loopback "driver", but with an interface 1948 * pointer that might NOT be a loopback interface -- evil, but easier than 1949 * replicating that code here. 1950 */ 1951 static void 1952 ip_mloopback(ifp, m, dst, hlen) 1953 struct ifnet *ifp; 1954 register struct mbuf *m; 1955 register struct sockaddr_in *dst; 1956 int hlen; 1957 { 1958 register struct ip *ip; 1959 struct mbuf *copym; 1960 1961 copym = m_copy(m, 0, M_COPYALL); 1962 if (copym != NULL && (copym->m_flags & M_EXT || copym->m_len < hlen)) 1963 copym = m_pullup(copym, hlen); 1964 if (copym != NULL) { 1965 /* If needed, compute the checksum and mark it as valid. */ 1966 if (copym->m_pkthdr.csum_flags & CSUM_DELAY_DATA) { 1967 in_delayed_cksum(copym); 1968 copym->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA; 1969 copym->m_pkthdr.csum_flags |= 1970 CSUM_DATA_VALID | CSUM_PSEUDO_HDR; 1971 copym->m_pkthdr.csum_data = 0xffff; 1972 } 1973 /* 1974 * We don't bother to fragment if the IP length is greater 1975 * than the interface's MTU. Can this possibly matter? 1976 */ 1977 ip = mtod(copym, struct ip *); 1978 ip->ip_len = htons(ip->ip_len); 1979 ip->ip_off = htons(ip->ip_off); 1980 ip->ip_sum = 0; 1981 ip->ip_sum = in_cksum(copym, hlen); 1982 /* 1983 * NB: 1984 * It's not clear whether there are any lingering 1985 * reentrancy problems in other areas which might 1986 * be exposed by using ip_input directly (in 1987 * particular, everything which modifies the packet 1988 * in-place). Yet another option is using the 1989 * protosw directly to deliver the looped back 1990 * packet. For the moment, we'll err on the side 1991 * of safety by using if_simloop(). 1992 */ 1993 #if 1 /* XXX */ 1994 if (dst->sin_family != AF_INET) { 1995 printf("ip_mloopback: bad address family %d\n", 1996 dst->sin_family); 1997 dst->sin_family = AF_INET; 1998 } 1999 #endif 2000 2001 #ifdef notdef 2002 copym->m_pkthdr.rcvif = ifp; 2003 ip_input(copym); 2004 #else 2005 if_simloop(ifp, copym, dst->sin_family, 0); 2006 #endif 2007 } 2008 } 2009