1 /* 2 * Copyright (c) 1982, 1986, 1988, 1990, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. 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: src/sys/netinet/ip_output.c,v 1.99.2.37 2003/04/15 06:44:45 silby Exp $ 31 * $DragonFly: src/sys/netinet/ip_output.c,v 1.67 2008/10/28 03:07:28 sephe Exp $ 32 */ 33 34 #define _IP_VHL 35 36 #include "opt_ipfw.h" 37 #include "opt_ipdn.h" 38 #include "opt_ipdivert.h" 39 #include "opt_ipfilter.h" 40 #include "opt_ipsec.h" 41 #include "opt_mbuf_stress_test.h" 42 #include "opt_mpls.h" 43 44 #include <sys/param.h> 45 #include <sys/systm.h> 46 #include <sys/kernel.h> 47 #include <sys/malloc.h> 48 #include <sys/mbuf.h> 49 #include <sys/protosw.h> 50 #include <sys/socket.h> 51 #include <sys/socketvar.h> 52 #include <sys/proc.h> 53 #include <sys/sysctl.h> 54 #include <sys/thread2.h> 55 #include <sys/in_cksum.h> 56 #include <sys/lock.h> 57 58 #include <net/if.h> 59 #include <net/netisr.h> 60 #include <net/pfil.h> 61 #include <net/route.h> 62 63 #include <netinet/in.h> 64 #include <netinet/in_systm.h> 65 #include <netinet/ip.h> 66 #include <netinet/in_pcb.h> 67 #include <netinet/in_var.h> 68 #include <netinet/ip_var.h> 69 70 #include <netproto/mpls/mpls_var.h> 71 72 static MALLOC_DEFINE(M_IPMOPTS, "ip_moptions", "internet multicast options"); 73 74 #ifdef IPSEC 75 #include <netinet6/ipsec.h> 76 #include <netproto/key/key.h> 77 #ifdef IPSEC_DEBUG 78 #include <netproto/key/key_debug.h> 79 #else 80 #define KEYDEBUG(lev,arg) 81 #endif 82 #endif /*IPSEC*/ 83 84 #ifdef FAST_IPSEC 85 #include <netproto/ipsec/ipsec.h> 86 #include <netproto/ipsec/xform.h> 87 #include <netproto/ipsec/key.h> 88 #endif /*FAST_IPSEC*/ 89 90 #include <net/ipfw/ip_fw.h> 91 #include <net/dummynet/ip_dummynet.h> 92 93 #define print_ip(x, a, y) kprintf("%s %d.%d.%d.%d%s",\ 94 x, (ntohl(a.s_addr)>>24)&0xFF,\ 95 (ntohl(a.s_addr)>>16)&0xFF,\ 96 (ntohl(a.s_addr)>>8)&0xFF,\ 97 (ntohl(a.s_addr))&0xFF, y); 98 99 u_short ip_id; 100 101 #ifdef MBUF_STRESS_TEST 102 int mbuf_frag_size = 0; 103 SYSCTL_INT(_net_inet_ip, OID_AUTO, mbuf_frag_size, CTLFLAG_RW, 104 &mbuf_frag_size, 0, "Fragment outgoing mbufs to this size"); 105 #endif 106 107 static struct mbuf *ip_insertoptions(struct mbuf *, struct mbuf *, int *); 108 static struct ifnet *ip_multicast_if(struct in_addr *, int *); 109 static void ip_mloopback 110 (struct ifnet *, struct mbuf *, struct sockaddr_in *, int); 111 static int ip_getmoptions 112 (struct sockopt *, struct ip_moptions *); 113 static int ip_pcbopts(int, struct mbuf **, struct mbuf *); 114 static int ip_setmoptions 115 (struct sockopt *, struct ip_moptions **); 116 117 int ip_optcopy(struct ip *, struct ip *); 118 119 extern int route_assert_owner_access; 120 121 extern struct protosw inetsw[]; 122 123 static int 124 ip_localforward(struct mbuf *m, const struct sockaddr_in *dst, int hlen) 125 { 126 struct in_ifaddr_container *iac; 127 128 /* 129 * We need to figure out if we have been forwarded to a local 130 * socket. If so, then we should somehow "loop back" to 131 * ip_input(), and get directed to the PCB as if we had received 132 * this packet. This is because it may be difficult to identify 133 * the packets you want to forward until they are being output 134 * and have selected an interface (e.g. locally initiated 135 * packets). If we used the loopback inteface, we would not be 136 * able to control what happens as the packet runs through 137 * ip_input() as it is done through a ISR. 138 */ 139 LIST_FOREACH(iac, INADDR_HASH(dst->sin_addr.s_addr), ia_hash) { 140 /* 141 * If the addr to forward to is one of ours, we pretend 142 * to be the destination for this packet. 143 */ 144 if (IA_SIN(iac->ia)->sin_addr.s_addr == dst->sin_addr.s_addr) 145 break; 146 } 147 if (iac != NULL) { 148 struct ip *ip; 149 150 if (m->m_pkthdr.rcvif == NULL) 151 m->m_pkthdr.rcvif = ifunit("lo0"); 152 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) { 153 m->m_pkthdr.csum_flags |= CSUM_DATA_VALID | 154 CSUM_PSEUDO_HDR; 155 m->m_pkthdr.csum_data = 0xffff; 156 } 157 m->m_pkthdr.csum_flags |= CSUM_IP_CHECKED | CSUM_IP_VALID; 158 159 /* 160 * Make sure that the IP header is in one mbuf, 161 * required by ip_input 162 */ 163 if (m->m_len < hlen) { 164 m = m_pullup(m, hlen); 165 if (m == NULL) { 166 /* The packet was freed; we are done */ 167 return 1; 168 } 169 } 170 ip = mtod(m, struct ip *); 171 172 ip->ip_len = htons(ip->ip_len); 173 ip->ip_off = htons(ip->ip_off); 174 ip_input(m); 175 176 return 1; /* The packet gets forwarded locally */ 177 } 178 return 0; 179 } 180 181 /* 182 * IP output. The packet in mbuf chain m contains a skeletal IP 183 * header (with len, off, ttl, proto, tos, src, dst). 184 * The mbuf chain containing the packet will be freed. 185 * The mbuf opt, if present, will not be freed. 186 */ 187 int 188 ip_output(struct mbuf *m0, struct mbuf *opt, struct route *ro, 189 int flags, struct ip_moptions *imo, struct inpcb *inp) 190 { 191 struct ip *ip; 192 struct ifnet *ifp = NULL; /* keep compiler happy */ 193 struct mbuf *m; 194 int hlen = sizeof(struct ip); 195 int len, error = 0; 196 struct sockaddr_in *dst = NULL; /* keep compiler happy */ 197 struct in_ifaddr *ia = NULL; 198 int isbroadcast, sw_csum; 199 struct in_addr pkt_dst; 200 struct route iproute; 201 struct m_tag *mtag; 202 #ifdef IPSEC 203 struct secpolicy *sp = NULL; 204 struct socket *so = inp ? inp->inp_socket : NULL; 205 #endif 206 #ifdef FAST_IPSEC 207 struct secpolicy *sp = NULL; 208 struct tdb_ident *tdbi; 209 #endif /* FAST_IPSEC */ 210 struct sockaddr_in *next_hop = NULL; 211 int src_was_INADDR_ANY = 0; /* as the name says... */ 212 213 m = m0; 214 M_ASSERTPKTHDR(m); 215 216 if (ro == NULL) { 217 ro = &iproute; 218 bzero(ro, sizeof *ro); 219 } else if (ro->ro_rt != NULL && ro->ro_rt->rt_cpuid != mycpuid) { 220 if (flags & IP_DEBUGROUTE) { 221 if (route_assert_owner_access) { 222 panic("ip_output: " 223 "rt rt_cpuid %d accessed on cpu %d\n", 224 ro->ro_rt->rt_cpuid, mycpuid); 225 } else { 226 kprintf("ip_output: " 227 "rt rt_cpuid %d accessed on cpu %d\n", 228 ro->ro_rt->rt_cpuid, mycpuid); 229 backtrace(); 230 } 231 } 232 233 /* 234 * XXX 235 * If the cached rtentry's owner CPU is not the current CPU, 236 * then don't touch the cached rtentry (remote free is too 237 * expensive in this context); just relocate the route. 238 */ 239 ro = &iproute; 240 bzero(ro, sizeof *ro); 241 } 242 243 if (m->m_pkthdr.fw_flags & IPFORWARD_MBUF_TAGGED) { 244 /* Next hop */ 245 mtag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL); 246 KKASSERT(mtag != NULL); 247 next_hop = m_tag_data(mtag); 248 } 249 250 if (m->m_pkthdr.fw_flags & DUMMYNET_MBUF_TAGGED) { 251 struct dn_pkt *dn_pkt; 252 253 /* Extract info from dummynet tag */ 254 mtag = m_tag_find(m, PACKET_TAG_DUMMYNET, NULL); 255 KKASSERT(mtag != NULL); 256 dn_pkt = m_tag_data(mtag); 257 258 /* 259 * The packet was already tagged, so part of the 260 * processing was already done, and we need to go down. 261 * Get the calculated parameters from the tag. 262 */ 263 ifp = dn_pkt->ifp; 264 265 KKASSERT(ro == &iproute); 266 *ro = dn_pkt->ro; /* structure copy */ 267 KKASSERT(ro->ro_rt == NULL || ro->ro_rt->rt_cpuid == mycpuid); 268 269 dst = dn_pkt->dn_dst; 270 if (dst == (struct sockaddr_in *)&(dn_pkt->ro.ro_dst)) { 271 /* If 'dst' points into dummynet tag, adjust it */ 272 dst = (struct sockaddr_in *)&(ro->ro_dst); 273 } 274 275 ip = mtod(m, struct ip *); 276 hlen = IP_VHL_HL(ip->ip_vhl) << 2 ; 277 if (ro->ro_rt) 278 ia = ifatoia(ro->ro_rt->rt_ifa); 279 goto sendit; 280 } 281 282 if (opt) { 283 len = 0; 284 m = ip_insertoptions(m, opt, &len); 285 if (len != 0) 286 hlen = len; 287 } 288 ip = mtod(m, struct ip *); 289 290 /* 291 * Fill in IP header. 292 */ 293 if (!(flags & (IP_FORWARDING|IP_RAWOUTPUT))) { 294 ip->ip_vhl = IP_MAKE_VHL(IPVERSION, hlen >> 2); 295 ip->ip_off &= IP_DF; 296 ip->ip_id = ip_newid(); 297 ipstat.ips_localout++; 298 } else { 299 hlen = IP_VHL_HL(ip->ip_vhl) << 2; 300 } 301 302 reroute: 303 pkt_dst = next_hop ? next_hop->sin_addr : ip->ip_dst; 304 305 #ifdef INVARIANTS 306 if (IN_MULTICAST(ntohl(pkt_dst.s_addr))) { 307 /* 308 * XXX 309 * Multicast is not MPSAFE yet. Caller must hold 310 * BGL when output a multicast IP packet. 311 */ 312 ASSERT_MP_LOCK_HELD(curthread); 313 } 314 #endif 315 316 dst = (struct sockaddr_in *)&ro->ro_dst; 317 /* 318 * If there is a cached route, 319 * check that it is to the same destination 320 * and is still up. If not, free it and try again. 321 * The address family should also be checked in case of sharing the 322 * cache with IPv6. 323 */ 324 if (ro->ro_rt && 325 (!(ro->ro_rt->rt_flags & RTF_UP) || 326 dst->sin_family != AF_INET || 327 dst->sin_addr.s_addr != pkt_dst.s_addr)) { 328 rtfree(ro->ro_rt); 329 ro->ro_rt = (struct rtentry *)NULL; 330 } 331 if (ro->ro_rt == NULL) { 332 bzero(dst, sizeof *dst); 333 dst->sin_family = AF_INET; 334 dst->sin_len = sizeof *dst; 335 dst->sin_addr = pkt_dst; 336 } 337 /* 338 * If routing to interface only, 339 * short circuit routing lookup. 340 */ 341 if (flags & IP_ROUTETOIF) { 342 if ((ia = ifatoia(ifa_ifwithdstaddr(sintosa(dst)))) == NULL && 343 (ia = ifatoia(ifa_ifwithnet(sintosa(dst)))) == NULL) { 344 ipstat.ips_noroute++; 345 error = ENETUNREACH; 346 goto bad; 347 } 348 ifp = ia->ia_ifp; 349 ip->ip_ttl = 1; 350 isbroadcast = in_broadcast(dst->sin_addr, ifp); 351 } else if (IN_MULTICAST(ntohl(pkt_dst.s_addr)) && 352 imo != NULL && imo->imo_multicast_ifp != NULL) { 353 /* 354 * Bypass the normal routing lookup for multicast 355 * packets if the interface is specified. 356 */ 357 ifp = imo->imo_multicast_ifp; 358 ia = IFP_TO_IA(ifp); 359 isbroadcast = 0; /* fool gcc */ 360 } else { 361 /* 362 * If this is the case, we probably don't want to allocate 363 * a protocol-cloned route since we didn't get one from the 364 * ULP. This lets TCP do its thing, while not burdening 365 * forwarding or ICMP with the overhead of cloning a route. 366 * Of course, we still want to do any cloning requested by 367 * the link layer, as this is probably required in all cases 368 * for correct operation (as it is for ARP). 369 */ 370 if (ro->ro_rt == NULL) 371 rtalloc_ign(ro, RTF_PRCLONING); 372 if (ro->ro_rt == NULL) { 373 ipstat.ips_noroute++; 374 error = EHOSTUNREACH; 375 goto bad; 376 } 377 ia = ifatoia(ro->ro_rt->rt_ifa); 378 ifp = ro->ro_rt->rt_ifp; 379 ro->ro_rt->rt_use++; 380 if (ro->ro_rt->rt_flags & RTF_GATEWAY) 381 dst = (struct sockaddr_in *)ro->ro_rt->rt_gateway; 382 if (ro->ro_rt->rt_flags & RTF_HOST) 383 isbroadcast = (ro->ro_rt->rt_flags & RTF_BROADCAST); 384 else 385 isbroadcast = in_broadcast(dst->sin_addr, ifp); 386 } 387 if (IN_MULTICAST(ntohl(pkt_dst.s_addr))) { 388 struct in_multi *inm; 389 390 m->m_flags |= M_MCAST; 391 /* 392 * IP destination address is multicast. Make sure "dst" 393 * still points to the address in "ro". (It may have been 394 * changed to point to a gateway address, above.) 395 */ 396 dst = (struct sockaddr_in *)&ro->ro_dst; 397 /* 398 * See if the caller provided any multicast options 399 */ 400 if (imo != NULL) { 401 ip->ip_ttl = imo->imo_multicast_ttl; 402 if (imo->imo_multicast_vif != -1) { 403 ip->ip_src.s_addr = 404 ip_mcast_src ? 405 ip_mcast_src(imo->imo_multicast_vif) : 406 INADDR_ANY; 407 } 408 } else { 409 ip->ip_ttl = IP_DEFAULT_MULTICAST_TTL; 410 } 411 /* 412 * Confirm that the outgoing interface supports multicast. 413 */ 414 if ((imo == NULL) || (imo->imo_multicast_vif == -1)) { 415 if (!(ifp->if_flags & IFF_MULTICAST)) { 416 ipstat.ips_noroute++; 417 error = ENETUNREACH; 418 goto bad; 419 } 420 } 421 /* 422 * If source address not specified yet, use address 423 * of outgoing interface. 424 */ 425 if (ip->ip_src.s_addr == INADDR_ANY) { 426 /* Interface may have no addresses. */ 427 if (ia != NULL) 428 ip->ip_src = IA_SIN(ia)->sin_addr; 429 } 430 431 IN_LOOKUP_MULTI(pkt_dst, ifp, inm); 432 if (inm != NULL && 433 (imo == NULL || imo->imo_multicast_loop)) { 434 /* 435 * If we belong to the destination multicast group 436 * on the outgoing interface, and the caller did not 437 * forbid loopback, loop back a copy. 438 */ 439 ip_mloopback(ifp, m, dst, hlen); 440 } else { 441 /* 442 * If we are acting as a multicast router, perform 443 * multicast forwarding as if the packet had just 444 * arrived on the interface to which we are about 445 * to send. The multicast forwarding function 446 * recursively calls this function, using the 447 * IP_FORWARDING flag to prevent infinite recursion. 448 * 449 * Multicasts that are looped back by ip_mloopback(), 450 * above, will be forwarded by the ip_input() routine, 451 * if necessary. 452 */ 453 if (ip_mrouter && !(flags & IP_FORWARDING)) { 454 /* 455 * If rsvp daemon is not running, do not 456 * set ip_moptions. This ensures that the packet 457 * is multicast and not just sent down one link 458 * as prescribed by rsvpd. 459 */ 460 if (!rsvp_on) 461 imo = NULL; 462 if (ip_mforward && 463 ip_mforward(ip, ifp, m, imo) != 0) { 464 m_freem(m); 465 goto done; 466 } 467 } 468 } 469 470 /* 471 * Multicasts with a time-to-live of zero may be looped- 472 * back, above, but must not be transmitted on a network. 473 * Also, multicasts addressed to the loopback interface 474 * are not sent -- the above call to ip_mloopback() will 475 * loop back a copy if this host actually belongs to the 476 * destination group on the loopback interface. 477 */ 478 if (ip->ip_ttl == 0 || ifp->if_flags & IFF_LOOPBACK) { 479 m_freem(m); 480 goto done; 481 } 482 483 goto sendit; 484 } else { 485 m->m_flags &= ~M_MCAST; 486 } 487 488 /* 489 * If the source address is not specified yet, use the address 490 * of the outoing interface. In case, keep note we did that, so 491 * if the the firewall changes the next-hop causing the output 492 * interface to change, we can fix that. 493 */ 494 if (ip->ip_src.s_addr == INADDR_ANY || src_was_INADDR_ANY) { 495 /* Interface may have no addresses. */ 496 if (ia != NULL) { 497 ip->ip_src = IA_SIN(ia)->sin_addr; 498 src_was_INADDR_ANY = 1; 499 } 500 } 501 502 #ifdef ALTQ 503 /* 504 * Disable packet drop hack. 505 * Packetdrop should be done by queueing. 506 */ 507 #else /* !ALTQ */ 508 /* 509 * Verify that we have any chance at all of being able to queue 510 * the packet or packet fragments 511 */ 512 if ((ifp->if_snd.ifq_len + ip->ip_len / ifp->if_mtu + 1) >= 513 ifp->if_snd.ifq_maxlen) { 514 error = ENOBUFS; 515 ipstat.ips_odropped++; 516 goto bad; 517 } 518 #endif /* !ALTQ */ 519 520 /* 521 * Look for broadcast address and 522 * verify user is allowed to send 523 * such a packet. 524 */ 525 if (isbroadcast) { 526 if (!(ifp->if_flags & IFF_BROADCAST)) { 527 error = EADDRNOTAVAIL; 528 goto bad; 529 } 530 if (!(flags & IP_ALLOWBROADCAST)) { 531 error = EACCES; 532 goto bad; 533 } 534 /* don't allow broadcast messages to be fragmented */ 535 if (ip->ip_len > ifp->if_mtu) { 536 error = EMSGSIZE; 537 goto bad; 538 } 539 m->m_flags |= M_BCAST; 540 } else { 541 m->m_flags &= ~M_BCAST; 542 } 543 544 sendit: 545 #ifdef IPSEC 546 /* get SP for this packet */ 547 if (so == NULL) 548 sp = ipsec4_getpolicybyaddr(m, IPSEC_DIR_OUTBOUND, flags, &error); 549 else 550 sp = ipsec4_getpolicybysock(m, IPSEC_DIR_OUTBOUND, so, &error); 551 552 if (sp == NULL) { 553 ipsecstat.out_inval++; 554 goto bad; 555 } 556 557 error = 0; 558 559 /* check policy */ 560 switch (sp->policy) { 561 case IPSEC_POLICY_DISCARD: 562 /* 563 * This packet is just discarded. 564 */ 565 ipsecstat.out_polvio++; 566 goto bad; 567 568 case IPSEC_POLICY_BYPASS: 569 case IPSEC_POLICY_NONE: 570 /* no need to do IPsec. */ 571 goto skip_ipsec; 572 573 case IPSEC_POLICY_IPSEC: 574 if (sp->req == NULL) { 575 /* acquire a policy */ 576 error = key_spdacquire(sp); 577 goto bad; 578 } 579 break; 580 581 case IPSEC_POLICY_ENTRUST: 582 default: 583 kprintf("ip_output: Invalid policy found. %d\n", sp->policy); 584 } 585 { 586 struct ipsec_output_state state; 587 bzero(&state, sizeof state); 588 state.m = m; 589 if (flags & IP_ROUTETOIF) { 590 state.ro = &iproute; 591 bzero(&iproute, sizeof iproute); 592 } else 593 state.ro = ro; 594 state.dst = (struct sockaddr *)dst; 595 596 ip->ip_sum = 0; 597 598 /* 599 * XXX 600 * delayed checksums are not currently compatible with IPsec 601 */ 602 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) { 603 in_delayed_cksum(m); 604 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA; 605 } 606 607 ip->ip_len = htons(ip->ip_len); 608 ip->ip_off = htons(ip->ip_off); 609 610 error = ipsec4_output(&state, sp, flags); 611 612 m = state.m; 613 if (flags & IP_ROUTETOIF) { 614 /* 615 * if we have tunnel mode SA, we may need to ignore 616 * IP_ROUTETOIF. 617 */ 618 if (state.ro != &iproute || state.ro->ro_rt != NULL) { 619 flags &= ~IP_ROUTETOIF; 620 ro = state.ro; 621 } 622 } else 623 ro = state.ro; 624 dst = (struct sockaddr_in *)state.dst; 625 if (error) { 626 /* mbuf is already reclaimed in ipsec4_output. */ 627 m0 = NULL; 628 switch (error) { 629 case EHOSTUNREACH: 630 case ENETUNREACH: 631 case EMSGSIZE: 632 case ENOBUFS: 633 case ENOMEM: 634 break; 635 default: 636 kprintf("ip4_output (ipsec): error code %d\n", error); 637 /*fall through*/ 638 case ENOENT: 639 /* don't show these error codes to the user */ 640 error = 0; 641 break; 642 } 643 goto bad; 644 } 645 } 646 647 /* be sure to update variables that are affected by ipsec4_output() */ 648 ip = mtod(m, struct ip *); 649 #ifdef _IP_VHL 650 hlen = IP_VHL_HL(ip->ip_vhl) << 2; 651 #else 652 hlen = ip->ip_hl << 2; 653 #endif 654 if (ro->ro_rt == NULL) { 655 if (!(flags & IP_ROUTETOIF)) { 656 kprintf("ip_output: " 657 "can't update route after IPsec processing\n"); 658 error = EHOSTUNREACH; /*XXX*/ 659 goto bad; 660 } 661 } else { 662 ia = ifatoia(ro->ro_rt->rt_ifa); 663 ifp = ro->ro_rt->rt_ifp; 664 } 665 666 /* make it flipped, again. */ 667 ip->ip_len = ntohs(ip->ip_len); 668 ip->ip_off = ntohs(ip->ip_off); 669 skip_ipsec: 670 #endif /*IPSEC*/ 671 #ifdef FAST_IPSEC 672 /* 673 * Check the security policy (SP) for the packet and, if 674 * required, do IPsec-related processing. There are two 675 * cases here; the first time a packet is sent through 676 * it will be untagged and handled by ipsec4_checkpolicy. 677 * If the packet is resubmitted to ip_output (e.g. after 678 * AH, ESP, etc. processing), there will be a tag to bypass 679 * the lookup and related policy checking. 680 */ 681 mtag = m_tag_find(m, PACKET_TAG_IPSEC_PENDING_TDB, NULL); 682 crit_enter(); 683 if (mtag != NULL) { 684 tdbi = (struct tdb_ident *)m_tag_data(mtag); 685 sp = ipsec_getpolicy(tdbi, IPSEC_DIR_OUTBOUND); 686 if (sp == NULL) 687 error = -EINVAL; /* force silent drop */ 688 m_tag_delete(m, mtag); 689 } else { 690 sp = ipsec4_checkpolicy(m, IPSEC_DIR_OUTBOUND, flags, 691 &error, inp); 692 } 693 /* 694 * There are four return cases: 695 * sp != NULL apply IPsec policy 696 * sp == NULL, error == 0 no IPsec handling needed 697 * sp == NULL, error == -EINVAL discard packet w/o error 698 * sp == NULL, error != 0 discard packet, report error 699 */ 700 if (sp != NULL) { 701 /* Loop detection, check if ipsec processing already done */ 702 KASSERT(sp->req != NULL, ("ip_output: no ipsec request")); 703 for (mtag = m_tag_first(m); mtag != NULL; 704 mtag = m_tag_next(m, mtag)) { 705 if (mtag->m_tag_cookie != MTAG_ABI_COMPAT) 706 continue; 707 if (mtag->m_tag_id != PACKET_TAG_IPSEC_OUT_DONE && 708 mtag->m_tag_id != PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED) 709 continue; 710 /* 711 * Check if policy has an SA associated with it. 712 * This can happen when an SP has yet to acquire 713 * an SA; e.g. on first reference. If it occurs, 714 * then we let ipsec4_process_packet do its thing. 715 */ 716 if (sp->req->sav == NULL) 717 break; 718 tdbi = (struct tdb_ident *)m_tag_data(mtag); 719 if (tdbi->spi == sp->req->sav->spi && 720 tdbi->proto == sp->req->sav->sah->saidx.proto && 721 bcmp(&tdbi->dst, &sp->req->sav->sah->saidx.dst, 722 sizeof(union sockaddr_union)) == 0) { 723 /* 724 * No IPsec processing is needed, free 725 * reference to SP. 726 * 727 * NB: null pointer to avoid free at 728 * done: below. 729 */ 730 KEY_FREESP(&sp), sp = NULL; 731 crit_exit(); 732 goto spd_done; 733 } 734 } 735 736 /* 737 * Do delayed checksums now because we send before 738 * this is done in the normal processing path. 739 */ 740 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) { 741 in_delayed_cksum(m); 742 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA; 743 } 744 745 ip->ip_len = htons(ip->ip_len); 746 ip->ip_off = htons(ip->ip_off); 747 748 /* NB: callee frees mbuf */ 749 error = ipsec4_process_packet(m, sp->req, flags, 0); 750 /* 751 * Preserve KAME behaviour: ENOENT can be returned 752 * when an SA acquire is in progress. Don't propagate 753 * this to user-level; it confuses applications. 754 * 755 * XXX this will go away when the SADB is redone. 756 */ 757 if (error == ENOENT) 758 error = 0; 759 crit_exit(); 760 goto done; 761 } else { 762 crit_exit(); 763 764 if (error != 0) { 765 /* 766 * Hack: -EINVAL is used to signal that a packet 767 * should be silently discarded. This is typically 768 * because we asked key management for an SA and 769 * it was delayed (e.g. kicked up to IKE). 770 */ 771 if (error == -EINVAL) 772 error = 0; 773 goto bad; 774 } else { 775 /* No IPsec processing for this packet. */ 776 } 777 #ifdef notyet 778 /* 779 * If deferred crypto processing is needed, check that 780 * the interface supports it. 781 */ 782 mtag = m_tag_find(m, PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED, NULL); 783 if (mtag != NULL && !(ifp->if_capenable & IFCAP_IPSEC)) { 784 /* notify IPsec to do its own crypto */ 785 ipsp_skipcrypto_unmark((struct tdb_ident *)m_tag_data(mtag)); 786 error = EHOSTUNREACH; 787 goto bad; 788 } 789 #endif 790 } 791 spd_done: 792 #endif /* FAST_IPSEC */ 793 794 /* We are already being fwd'd from a firewall. */ 795 if (next_hop != NULL) 796 goto pass; 797 798 /* No pfil hooks */ 799 if (!pfil_has_hooks(&inet_pfil_hook)) { 800 if (m->m_pkthdr.fw_flags & DUMMYNET_MBUF_TAGGED) { 801 /* 802 * Strip dummynet tags from stranded packets 803 */ 804 mtag = m_tag_find(m, PACKET_TAG_DUMMYNET, NULL); 805 KKASSERT(mtag != NULL); 806 m_tag_delete(m, mtag); 807 m->m_pkthdr.fw_flags &= ~DUMMYNET_MBUF_TAGGED; 808 } 809 goto pass; 810 } 811 812 /* 813 * IpHack's section. 814 * - Xlate: translate packet's addr/port (NAT). 815 * - Firewall: deny/allow/etc. 816 * - Wrap: fake packet's addr/port <unimpl.> 817 * - Encapsulate: put it in another IP and send out. <unimp.> 818 */ 819 820 /* 821 * Run through list of hooks for output packets. 822 */ 823 error = pfil_run_hooks(&inet_pfil_hook, &m, ifp, PFIL_OUT); 824 if (error != 0 || m == NULL) 825 goto done; 826 ip = mtod(m, struct ip *); 827 828 if (m->m_pkthdr.fw_flags & IPFORWARD_MBUF_TAGGED) { 829 /* 830 * Check dst to make sure it is directly reachable on the 831 * interface we previously thought it was. 832 * If it isn't (which may be likely in some situations) we have 833 * to re-route it (ie, find a route for the next-hop and the 834 * associated interface) and set them here. This is nested 835 * forwarding which in most cases is undesirable, except where 836 * such control is nigh impossible. So we do it here. 837 * And I'm babbling. 838 */ 839 mtag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL); 840 KKASSERT(mtag != NULL); 841 next_hop = m_tag_data(mtag); 842 843 /* 844 * Try local forwarding first 845 */ 846 if (ip_localforward(m, next_hop, hlen)) 847 goto done; 848 849 /* 850 * Relocate the route based on next_hop. 851 * If the current route is inp's cache, keep it untouched. 852 */ 853 if (ro == &iproute && ro->ro_rt != NULL) { 854 RTFREE(ro->ro_rt); 855 ro->ro_rt = NULL; 856 } 857 ro = &iproute; 858 bzero(ro, sizeof *ro); 859 860 /* 861 * Forwarding to broadcast address is not allowed. 862 * XXX Should we follow IP_ROUTETOIF? 863 */ 864 flags &= ~(IP_ALLOWBROADCAST | IP_ROUTETOIF); 865 866 /* We are doing forwarding now */ 867 flags |= IP_FORWARDING; 868 869 goto reroute; 870 } 871 872 if (m->m_pkthdr.fw_flags & DUMMYNET_MBUF_TAGGED) { 873 struct dn_pkt *dn_pkt; 874 875 mtag = m_tag_find(m, PACKET_TAG_DUMMYNET, NULL); 876 KKASSERT(mtag != NULL); 877 dn_pkt = m_tag_data(mtag); 878 879 /* 880 * Under certain cases it is not possible to recalculate 881 * 'ro' and 'dst', let alone 'flags', so just save them in 882 * dummynet tag and avoid the possible wrong reculcalation 883 * when we come back to ip_output() again. 884 * 885 * All other parameters have been already used and so they 886 * are not needed anymore. 887 * XXX if the ifp is deleted while a pkt is in dummynet, 888 * we are in trouble! (TODO use ifnet_detach_event) 889 * 890 * We need to copy *ro because for ICMP pkts (and maybe 891 * others) the caller passed a pointer into the stack; 892 * dst might also be a pointer into *ro so it needs to 893 * be updated. 894 */ 895 dn_pkt->ro = *ro; 896 if (ro->ro_rt) 897 ro->ro_rt->rt_refcnt++; 898 if (dst == (struct sockaddr_in *)&ro->ro_dst) { 899 /* 'dst' points into 'ro' */ 900 dst = (struct sockaddr_in *)&(dn_pkt->ro.ro_dst); 901 } 902 dn_pkt->dn_dst = dst; 903 dn_pkt->flags = flags; 904 905 ip_dn_queue(m); 906 goto done; 907 } 908 pass: 909 /* 127/8 must not appear on wire - RFC1122. */ 910 if ((ntohl(ip->ip_dst.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET || 911 (ntohl(ip->ip_src.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET) { 912 if (!(ifp->if_flags & IFF_LOOPBACK)) { 913 ipstat.ips_badaddr++; 914 error = EADDRNOTAVAIL; 915 goto bad; 916 } 917 } 918 919 m->m_pkthdr.csum_flags |= CSUM_IP; 920 sw_csum = m->m_pkthdr.csum_flags & ~ifp->if_hwassist; 921 if (sw_csum & CSUM_DELAY_DATA) { 922 in_delayed_cksum(m); 923 sw_csum &= ~CSUM_DELAY_DATA; 924 } 925 m->m_pkthdr.csum_flags &= ifp->if_hwassist; 926 927 /* 928 * If small enough for interface, or the interface will take 929 * care of the fragmentation for us, can just send directly. 930 */ 931 if (ip->ip_len <= ifp->if_mtu || ((ifp->if_hwassist & CSUM_FRAGMENT) && 932 !(ip->ip_off & IP_DF))) { 933 ip->ip_len = htons(ip->ip_len); 934 ip->ip_off = htons(ip->ip_off); 935 ip->ip_sum = 0; 936 if (sw_csum & CSUM_DELAY_IP) { 937 if (ip->ip_vhl == IP_VHL_BORING) 938 ip->ip_sum = in_cksum_hdr(ip); 939 else 940 ip->ip_sum = in_cksum(m, hlen); 941 } 942 943 /* Record statistics for this interface address. */ 944 if (!(flags & IP_FORWARDING) && ia) { 945 ia->ia_ifa.if_opackets++; 946 ia->ia_ifa.if_obytes += m->m_pkthdr.len; 947 } 948 949 #ifdef IPSEC 950 /* clean ipsec history once it goes out of the node */ 951 ipsec_delaux(m); 952 #endif 953 954 #ifdef MBUF_STRESS_TEST 955 if (mbuf_frag_size && m->m_pkthdr.len > mbuf_frag_size) { 956 struct mbuf *m1, *m2; 957 int length, tmp; 958 959 tmp = length = m->m_pkthdr.len; 960 961 while ((length -= mbuf_frag_size) >= 1) { 962 m1 = m_split(m, length, MB_DONTWAIT); 963 if (m1 == NULL) 964 break; 965 m2 = m; 966 while (m2->m_next != NULL) 967 m2 = m2->m_next; 968 m2->m_next = m1; 969 } 970 m->m_pkthdr.len = tmp; 971 } 972 #endif 973 974 #ifdef MPLS 975 if (!mpls_output_process(m, ro->ro_rt)) 976 goto done; 977 #endif 978 error = ifp->if_output(ifp, m, (struct sockaddr *)dst, 979 ro->ro_rt); 980 goto done; 981 } 982 983 if (ip->ip_off & IP_DF) { 984 error = EMSGSIZE; 985 /* 986 * This case can happen if the user changed the MTU 987 * of an interface after enabling IP on it. Because 988 * most netifs don't keep track of routes pointing to 989 * them, there is no way for one to update all its 990 * routes when the MTU is changed. 991 */ 992 if ((ro->ro_rt->rt_flags & (RTF_UP | RTF_HOST)) && 993 !(ro->ro_rt->rt_rmx.rmx_locks & RTV_MTU) && 994 (ro->ro_rt->rt_rmx.rmx_mtu > ifp->if_mtu)) { 995 ro->ro_rt->rt_rmx.rmx_mtu = ifp->if_mtu; 996 } 997 ipstat.ips_cantfrag++; 998 goto bad; 999 } 1000 1001 /* 1002 * Too large for interface; fragment if possible. If successful, 1003 * on return, m will point to a list of packets to be sent. 1004 */ 1005 error = ip_fragment(ip, &m, ifp->if_mtu, ifp->if_hwassist, sw_csum); 1006 if (error) 1007 goto bad; 1008 for (; m; m = m0) { 1009 m0 = m->m_nextpkt; 1010 m->m_nextpkt = NULL; 1011 #ifdef IPSEC 1012 /* clean ipsec history once it goes out of the node */ 1013 ipsec_delaux(m); 1014 #endif 1015 if (error == 0) { 1016 /* Record statistics for this interface address. */ 1017 if (ia != NULL) { 1018 ia->ia_ifa.if_opackets++; 1019 ia->ia_ifa.if_obytes += m->m_pkthdr.len; 1020 } 1021 #ifdef MPLS 1022 if (!mpls_output_process(m, ro->ro_rt)) 1023 continue; 1024 #endif 1025 error = ifp->if_output(ifp, m, (struct sockaddr *)dst, 1026 ro->ro_rt); 1027 } else { 1028 m_freem(m); 1029 } 1030 } 1031 1032 if (error == 0) 1033 ipstat.ips_fragmented++; 1034 1035 done: 1036 if (ro == &iproute && ro->ro_rt != NULL) { 1037 RTFREE(ro->ro_rt); 1038 ro->ro_rt = NULL; 1039 } 1040 #ifdef IPSEC 1041 if (sp != NULL) { 1042 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 1043 kprintf("DP ip_output call free SP:%p\n", sp)); 1044 key_freesp(sp); 1045 } 1046 #endif 1047 #ifdef FAST_IPSEC 1048 if (sp != NULL) 1049 KEY_FREESP(&sp); 1050 #endif 1051 return (error); 1052 bad: 1053 m_freem(m); 1054 goto done; 1055 } 1056 1057 /* 1058 * Create a chain of fragments which fit the given mtu. m_frag points to the 1059 * mbuf to be fragmented; on return it points to the chain with the fragments. 1060 * Return 0 if no error. If error, m_frag may contain a partially built 1061 * chain of fragments that should be freed by the caller. 1062 * 1063 * if_hwassist_flags is the hw offload capabilities (see if_data.ifi_hwassist) 1064 * sw_csum contains the delayed checksums flags (e.g., CSUM_DELAY_IP). 1065 */ 1066 int 1067 ip_fragment(struct ip *ip, struct mbuf **m_frag, int mtu, 1068 u_long if_hwassist_flags, int sw_csum) 1069 { 1070 int error = 0; 1071 int hlen = IP_VHL_HL(ip->ip_vhl) << 2; 1072 int len = (mtu - hlen) & ~7; /* size of payload in each fragment */ 1073 int off; 1074 struct mbuf *m0 = *m_frag; /* the original packet */ 1075 int firstlen; 1076 struct mbuf **mnext; 1077 int nfrags; 1078 1079 if (ip->ip_off & IP_DF) { /* Fragmentation not allowed */ 1080 ipstat.ips_cantfrag++; 1081 return EMSGSIZE; 1082 } 1083 1084 /* 1085 * Must be able to put at least 8 bytes per fragment. 1086 */ 1087 if (len < 8) 1088 return EMSGSIZE; 1089 1090 /* 1091 * If the interface will not calculate checksums on 1092 * fragmented packets, then do it here. 1093 */ 1094 if ((m0->m_pkthdr.csum_flags & CSUM_DELAY_DATA) && 1095 !(if_hwassist_flags & CSUM_IP_FRAGS)) { 1096 in_delayed_cksum(m0); 1097 m0->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA; 1098 } 1099 1100 if (len > PAGE_SIZE) { 1101 /* 1102 * Fragment large datagrams such that each segment 1103 * contains a multiple of PAGE_SIZE amount of data, 1104 * plus headers. This enables a receiver to perform 1105 * page-flipping zero-copy optimizations. 1106 * 1107 * XXX When does this help given that sender and receiver 1108 * could have different page sizes, and also mtu could 1109 * be less than the receiver's page size ? 1110 */ 1111 int newlen; 1112 struct mbuf *m; 1113 1114 for (m = m0, off = 0; m && (off+m->m_len) <= mtu; m = m->m_next) 1115 off += m->m_len; 1116 1117 /* 1118 * firstlen (off - hlen) must be aligned on an 1119 * 8-byte boundary 1120 */ 1121 if (off < hlen) 1122 goto smart_frag_failure; 1123 off = ((off - hlen) & ~7) + hlen; 1124 newlen = (~PAGE_MASK) & mtu; 1125 if ((newlen + sizeof(struct ip)) > mtu) { 1126 /* we failed, go back the default */ 1127 smart_frag_failure: 1128 newlen = len; 1129 off = hlen + len; 1130 } 1131 len = newlen; 1132 1133 } else { 1134 off = hlen + len; 1135 } 1136 1137 firstlen = off - hlen; 1138 mnext = &m0->m_nextpkt; /* pointer to next packet */ 1139 1140 /* 1141 * Loop through length of segment after first fragment, 1142 * make new header and copy data of each part and link onto chain. 1143 * Here, m0 is the original packet, m is the fragment being created. 1144 * The fragments are linked off the m_nextpkt of the original 1145 * packet, which after processing serves as the first fragment. 1146 */ 1147 for (nfrags = 1; off < ip->ip_len; off += len, nfrags++) { 1148 struct ip *mhip; /* ip header on the fragment */ 1149 struct mbuf *m; 1150 int mhlen = sizeof(struct ip); 1151 1152 MGETHDR(m, MB_DONTWAIT, MT_HEADER); 1153 if (m == NULL) { 1154 error = ENOBUFS; 1155 ipstat.ips_odropped++; 1156 goto done; 1157 } 1158 m->m_flags |= (m0->m_flags & M_MCAST) | M_FRAG; 1159 /* 1160 * In the first mbuf, leave room for the link header, then 1161 * copy the original IP header including options. The payload 1162 * goes into an additional mbuf chain returned by m_copy(). 1163 */ 1164 m->m_data += max_linkhdr; 1165 mhip = mtod(m, struct ip *); 1166 *mhip = *ip; 1167 if (hlen > sizeof(struct ip)) { 1168 mhlen = ip_optcopy(ip, mhip) + sizeof(struct ip); 1169 mhip->ip_vhl = IP_MAKE_VHL(IPVERSION, mhlen >> 2); 1170 } 1171 m->m_len = mhlen; 1172 /* XXX do we need to add ip->ip_off below ? */ 1173 mhip->ip_off = ((off - hlen) >> 3) + ip->ip_off; 1174 if (off + len >= ip->ip_len) { /* last fragment */ 1175 len = ip->ip_len - off; 1176 m->m_flags |= M_LASTFRAG; 1177 } else 1178 mhip->ip_off |= IP_MF; 1179 mhip->ip_len = htons((u_short)(len + mhlen)); 1180 m->m_next = m_copy(m0, off, len); 1181 if (m->m_next == NULL) { /* copy failed */ 1182 m_free(m); 1183 error = ENOBUFS; /* ??? */ 1184 ipstat.ips_odropped++; 1185 goto done; 1186 } 1187 m->m_pkthdr.len = mhlen + len; 1188 m->m_pkthdr.rcvif = (struct ifnet *)NULL; 1189 m->m_pkthdr.csum_flags = m0->m_pkthdr.csum_flags; 1190 mhip->ip_off = htons(mhip->ip_off); 1191 mhip->ip_sum = 0; 1192 if (sw_csum & CSUM_DELAY_IP) 1193 mhip->ip_sum = in_cksum(m, mhlen); 1194 *mnext = m; 1195 mnext = &m->m_nextpkt; 1196 } 1197 ipstat.ips_ofragments += nfrags; 1198 1199 /* set first marker for fragment chain */ 1200 m0->m_flags |= M_FIRSTFRAG | M_FRAG; 1201 m0->m_pkthdr.csum_data = nfrags; 1202 1203 /* 1204 * Update first fragment by trimming what's been copied out 1205 * and updating header. 1206 */ 1207 m_adj(m0, hlen + firstlen - ip->ip_len); 1208 m0->m_pkthdr.len = hlen + firstlen; 1209 ip->ip_len = htons((u_short)m0->m_pkthdr.len); 1210 ip->ip_off |= IP_MF; 1211 ip->ip_off = htons(ip->ip_off); 1212 ip->ip_sum = 0; 1213 if (sw_csum & CSUM_DELAY_IP) 1214 ip->ip_sum = in_cksum(m0, hlen); 1215 1216 done: 1217 *m_frag = m0; 1218 return error; 1219 } 1220 1221 void 1222 in_delayed_cksum(struct mbuf *m) 1223 { 1224 struct ip *ip; 1225 u_short csum, offset; 1226 1227 ip = mtod(m, struct ip *); 1228 offset = IP_VHL_HL(ip->ip_vhl) << 2 ; 1229 csum = in_cksum_skip(m, ip->ip_len, offset); 1230 if (m->m_pkthdr.csum_flags & CSUM_UDP && csum == 0) 1231 csum = 0xffff; 1232 offset += m->m_pkthdr.csum_data; /* checksum offset */ 1233 1234 if (offset + sizeof(u_short) > m->m_len) { 1235 kprintf("delayed m_pullup, m->len: %d off: %d p: %d\n", 1236 m->m_len, offset, ip->ip_p); 1237 /* 1238 * XXX 1239 * this shouldn't happen, but if it does, the 1240 * correct behavior may be to insert the checksum 1241 * in the existing chain instead of rearranging it. 1242 */ 1243 m = m_pullup(m, offset + sizeof(u_short)); 1244 } 1245 *(u_short *)(m->m_data + offset) = csum; 1246 } 1247 1248 /* 1249 * Insert IP options into preformed packet. 1250 * Adjust IP destination as required for IP source routing, 1251 * as indicated by a non-zero in_addr at the start of the options. 1252 * 1253 * XXX This routine assumes that the packet has no options in place. 1254 */ 1255 static struct mbuf * 1256 ip_insertoptions(struct mbuf *m, struct mbuf *opt, int *phlen) 1257 { 1258 struct ipoption *p = mtod(opt, struct ipoption *); 1259 struct mbuf *n; 1260 struct ip *ip = mtod(m, struct ip *); 1261 unsigned optlen; 1262 1263 optlen = opt->m_len - sizeof p->ipopt_dst; 1264 if (optlen + (u_short)ip->ip_len > IP_MAXPACKET) { 1265 *phlen = 0; 1266 return (m); /* XXX should fail */ 1267 } 1268 if (p->ipopt_dst.s_addr) 1269 ip->ip_dst = p->ipopt_dst; 1270 if (m->m_flags & M_EXT || m->m_data - optlen < m->m_pktdat) { 1271 MGETHDR(n, MB_DONTWAIT, MT_HEADER); 1272 if (n == NULL) { 1273 *phlen = 0; 1274 return (m); 1275 } 1276 n->m_pkthdr.rcvif = (struct ifnet *)NULL; 1277 n->m_pkthdr.len = m->m_pkthdr.len + optlen; 1278 m->m_len -= sizeof(struct ip); 1279 m->m_data += sizeof(struct ip); 1280 n->m_next = m; 1281 m = n; 1282 m->m_len = optlen + sizeof(struct ip); 1283 m->m_data += max_linkhdr; 1284 memcpy(mtod(m, void *), ip, sizeof(struct ip)); 1285 } else { 1286 m->m_data -= optlen; 1287 m->m_len += optlen; 1288 m->m_pkthdr.len += optlen; 1289 ovbcopy(ip, mtod(m, caddr_t), sizeof(struct ip)); 1290 } 1291 ip = mtod(m, struct ip *); 1292 bcopy(p->ipopt_list, ip + 1, optlen); 1293 *phlen = sizeof(struct ip) + optlen; 1294 ip->ip_vhl = IP_MAKE_VHL(IPVERSION, *phlen >> 2); 1295 ip->ip_len += optlen; 1296 return (m); 1297 } 1298 1299 /* 1300 * Copy options from ip to jp, 1301 * omitting those not copied during fragmentation. 1302 */ 1303 int 1304 ip_optcopy(struct ip *ip, struct ip *jp) 1305 { 1306 u_char *cp, *dp; 1307 int opt, optlen, cnt; 1308 1309 cp = (u_char *)(ip + 1); 1310 dp = (u_char *)(jp + 1); 1311 cnt = (IP_VHL_HL(ip->ip_vhl) << 2) - sizeof(struct ip); 1312 for (; cnt > 0; cnt -= optlen, cp += optlen) { 1313 opt = cp[0]; 1314 if (opt == IPOPT_EOL) 1315 break; 1316 if (opt == IPOPT_NOP) { 1317 /* Preserve for IP mcast tunnel's LSRR alignment. */ 1318 *dp++ = IPOPT_NOP; 1319 optlen = 1; 1320 continue; 1321 } 1322 1323 KASSERT(cnt >= IPOPT_OLEN + sizeof *cp, 1324 ("ip_optcopy: malformed ipv4 option")); 1325 optlen = cp[IPOPT_OLEN]; 1326 KASSERT(optlen >= IPOPT_OLEN + sizeof *cp && optlen <= cnt, 1327 ("ip_optcopy: malformed ipv4 option")); 1328 1329 /* bogus lengths should have been caught by ip_dooptions */ 1330 if (optlen > cnt) 1331 optlen = cnt; 1332 if (IPOPT_COPIED(opt)) { 1333 bcopy(cp, dp, optlen); 1334 dp += optlen; 1335 } 1336 } 1337 for (optlen = dp - (u_char *)(jp+1); optlen & 0x3; optlen++) 1338 *dp++ = IPOPT_EOL; 1339 return (optlen); 1340 } 1341 1342 /* 1343 * IP socket option processing. 1344 */ 1345 int 1346 ip_ctloutput(struct socket *so, struct sockopt *sopt) 1347 { 1348 struct inpcb *inp = so->so_pcb; 1349 int error, optval; 1350 1351 error = optval = 0; 1352 if (sopt->sopt_level != IPPROTO_IP) { 1353 return (EINVAL); 1354 } 1355 1356 switch (sopt->sopt_dir) { 1357 case SOPT_SET: 1358 switch (sopt->sopt_name) { 1359 case IP_OPTIONS: 1360 #ifdef notyet 1361 case IP_RETOPTS: 1362 #endif 1363 { 1364 struct mbuf *m; 1365 if (sopt->sopt_valsize > MLEN) { 1366 error = EMSGSIZE; 1367 break; 1368 } 1369 MGET(m, sopt->sopt_td ? MB_WAIT : MB_DONTWAIT, MT_HEADER); 1370 if (m == NULL) { 1371 error = ENOBUFS; 1372 break; 1373 } 1374 m->m_len = sopt->sopt_valsize; 1375 error = soopt_to_kbuf(sopt, mtod(m, void *), m->m_len, 1376 m->m_len); 1377 return (ip_pcbopts(sopt->sopt_name, &inp->inp_options, 1378 m)); 1379 } 1380 1381 case IP_TOS: 1382 case IP_TTL: 1383 case IP_MINTTL: 1384 case IP_RECVOPTS: 1385 case IP_RECVRETOPTS: 1386 case IP_RECVDSTADDR: 1387 case IP_RECVIF: 1388 case IP_RECVTTL: 1389 case IP_FAITH: 1390 error = soopt_to_kbuf(sopt, &optval, sizeof optval, 1391 sizeof optval); 1392 if (error) 1393 break; 1394 switch (sopt->sopt_name) { 1395 case IP_TOS: 1396 inp->inp_ip_tos = optval; 1397 break; 1398 1399 case IP_TTL: 1400 inp->inp_ip_ttl = optval; 1401 break; 1402 case IP_MINTTL: 1403 if (optval > 0 && optval <= MAXTTL) 1404 inp->inp_ip_minttl = optval; 1405 else 1406 error = EINVAL; 1407 break; 1408 #define OPTSET(bit) \ 1409 if (optval) \ 1410 inp->inp_flags |= bit; \ 1411 else \ 1412 inp->inp_flags &= ~bit; 1413 1414 case IP_RECVOPTS: 1415 OPTSET(INP_RECVOPTS); 1416 break; 1417 1418 case IP_RECVRETOPTS: 1419 OPTSET(INP_RECVRETOPTS); 1420 break; 1421 1422 case IP_RECVDSTADDR: 1423 OPTSET(INP_RECVDSTADDR); 1424 break; 1425 1426 case IP_RECVIF: 1427 OPTSET(INP_RECVIF); 1428 break; 1429 1430 case IP_RECVTTL: 1431 OPTSET(INP_RECVTTL); 1432 break; 1433 1434 case IP_FAITH: 1435 OPTSET(INP_FAITH); 1436 break; 1437 } 1438 break; 1439 #undef OPTSET 1440 1441 case IP_MULTICAST_IF: 1442 case IP_MULTICAST_VIF: 1443 case IP_MULTICAST_TTL: 1444 case IP_MULTICAST_LOOP: 1445 case IP_ADD_MEMBERSHIP: 1446 case IP_DROP_MEMBERSHIP: 1447 error = ip_setmoptions(sopt, &inp->inp_moptions); 1448 break; 1449 1450 case IP_PORTRANGE: 1451 error = soopt_to_kbuf(sopt, &optval, sizeof optval, 1452 sizeof optval); 1453 if (error) 1454 break; 1455 1456 switch (optval) { 1457 case IP_PORTRANGE_DEFAULT: 1458 inp->inp_flags &= ~(INP_LOWPORT); 1459 inp->inp_flags &= ~(INP_HIGHPORT); 1460 break; 1461 1462 case IP_PORTRANGE_HIGH: 1463 inp->inp_flags &= ~(INP_LOWPORT); 1464 inp->inp_flags |= INP_HIGHPORT; 1465 break; 1466 1467 case IP_PORTRANGE_LOW: 1468 inp->inp_flags &= ~(INP_HIGHPORT); 1469 inp->inp_flags |= INP_LOWPORT; 1470 break; 1471 1472 default: 1473 error = EINVAL; 1474 break; 1475 } 1476 break; 1477 1478 #if defined(IPSEC) || defined(FAST_IPSEC) 1479 case IP_IPSEC_POLICY: 1480 { 1481 caddr_t req; 1482 size_t len = 0; 1483 int priv; 1484 struct mbuf *m; 1485 int optname; 1486 1487 if ((error = soopt_getm(sopt, &m)) != 0) /* XXX */ 1488 break; 1489 soopt_to_mbuf(sopt, m); 1490 priv = (sopt->sopt_td != NULL && 1491 suser(sopt->sopt_td) != 0) ? 0 : 1; 1492 req = mtod(m, caddr_t); 1493 len = m->m_len; 1494 optname = sopt->sopt_name; 1495 error = ipsec4_set_policy(inp, optname, req, len, priv); 1496 m_freem(m); 1497 break; 1498 } 1499 #endif /*IPSEC*/ 1500 1501 default: 1502 error = ENOPROTOOPT; 1503 break; 1504 } 1505 break; 1506 1507 case SOPT_GET: 1508 switch (sopt->sopt_name) { 1509 case IP_OPTIONS: 1510 case IP_RETOPTS: 1511 if (inp->inp_options) 1512 soopt_from_kbuf(sopt, mtod(inp->inp_options, 1513 char *), 1514 inp->inp_options->m_len); 1515 else 1516 sopt->sopt_valsize = 0; 1517 break; 1518 1519 case IP_TOS: 1520 case IP_TTL: 1521 case IP_MINTTL: 1522 case IP_RECVOPTS: 1523 case IP_RECVRETOPTS: 1524 case IP_RECVDSTADDR: 1525 case IP_RECVTTL: 1526 case IP_RECVIF: 1527 case IP_PORTRANGE: 1528 case IP_FAITH: 1529 switch (sopt->sopt_name) { 1530 1531 case IP_TOS: 1532 optval = inp->inp_ip_tos; 1533 break; 1534 1535 case IP_TTL: 1536 optval = inp->inp_ip_ttl; 1537 break; 1538 case IP_MINTTL: 1539 optval = inp->inp_ip_minttl; 1540 break; 1541 1542 #define OPTBIT(bit) (inp->inp_flags & bit ? 1 : 0) 1543 1544 case IP_RECVOPTS: 1545 optval = OPTBIT(INP_RECVOPTS); 1546 break; 1547 1548 case IP_RECVRETOPTS: 1549 optval = OPTBIT(INP_RECVRETOPTS); 1550 break; 1551 1552 case IP_RECVDSTADDR: 1553 optval = OPTBIT(INP_RECVDSTADDR); 1554 break; 1555 1556 case IP_RECVTTL: 1557 optval = OPTBIT(INP_RECVTTL); 1558 break; 1559 1560 case IP_RECVIF: 1561 optval = OPTBIT(INP_RECVIF); 1562 break; 1563 1564 case IP_PORTRANGE: 1565 if (inp->inp_flags & INP_HIGHPORT) 1566 optval = IP_PORTRANGE_HIGH; 1567 else if (inp->inp_flags & INP_LOWPORT) 1568 optval = IP_PORTRANGE_LOW; 1569 else 1570 optval = 0; 1571 break; 1572 1573 case IP_FAITH: 1574 optval = OPTBIT(INP_FAITH); 1575 break; 1576 } 1577 soopt_from_kbuf(sopt, &optval, sizeof optval); 1578 break; 1579 1580 case IP_MULTICAST_IF: 1581 case IP_MULTICAST_VIF: 1582 case IP_MULTICAST_TTL: 1583 case IP_MULTICAST_LOOP: 1584 case IP_ADD_MEMBERSHIP: 1585 case IP_DROP_MEMBERSHIP: 1586 error = ip_getmoptions(sopt, inp->inp_moptions); 1587 break; 1588 1589 #if defined(IPSEC) || defined(FAST_IPSEC) 1590 case IP_IPSEC_POLICY: 1591 { 1592 struct mbuf *m = NULL; 1593 caddr_t req = NULL; 1594 size_t len = 0; 1595 1596 if (m != NULL) { 1597 req = mtod(m, caddr_t); 1598 len = m->m_len; 1599 } 1600 error = ipsec4_get_policy(so->so_pcb, req, len, &m); 1601 if (error == 0) 1602 error = soopt_from_mbuf(sopt, m); /* XXX */ 1603 if (error == 0) 1604 m_freem(m); 1605 break; 1606 } 1607 #endif /*IPSEC*/ 1608 1609 default: 1610 error = ENOPROTOOPT; 1611 break; 1612 } 1613 break; 1614 } 1615 return (error); 1616 } 1617 1618 /* 1619 * Set up IP options in pcb for insertion in output packets. 1620 * Store in mbuf with pointer in pcbopt, adding pseudo-option 1621 * with destination address if source routed. 1622 */ 1623 static int 1624 ip_pcbopts(int optname, struct mbuf **pcbopt, struct mbuf *m) 1625 { 1626 int cnt, optlen; 1627 u_char *cp; 1628 u_char opt; 1629 1630 /* turn off any old options */ 1631 if (*pcbopt) 1632 m_free(*pcbopt); 1633 *pcbopt = 0; 1634 if (m == NULL || m->m_len == 0) { 1635 /* 1636 * Only turning off any previous options. 1637 */ 1638 if (m != NULL) 1639 m_free(m); 1640 return (0); 1641 } 1642 1643 if (m->m_len % sizeof(int32_t)) 1644 goto bad; 1645 /* 1646 * IP first-hop destination address will be stored before 1647 * actual options; move other options back 1648 * and clear it when none present. 1649 */ 1650 if (m->m_data + m->m_len + sizeof(struct in_addr) >= &m->m_dat[MLEN]) 1651 goto bad; 1652 cnt = m->m_len; 1653 m->m_len += sizeof(struct in_addr); 1654 cp = mtod(m, u_char *) + sizeof(struct in_addr); 1655 ovbcopy(mtod(m, caddr_t), cp, cnt); 1656 bzero(mtod(m, caddr_t), sizeof(struct in_addr)); 1657 1658 for (; cnt > 0; cnt -= optlen, cp += optlen) { 1659 opt = cp[IPOPT_OPTVAL]; 1660 if (opt == IPOPT_EOL) 1661 break; 1662 if (opt == IPOPT_NOP) 1663 optlen = 1; 1664 else { 1665 if (cnt < IPOPT_OLEN + sizeof *cp) 1666 goto bad; 1667 optlen = cp[IPOPT_OLEN]; 1668 if (optlen < IPOPT_OLEN + sizeof *cp || optlen > cnt) 1669 goto bad; 1670 } 1671 switch (opt) { 1672 1673 default: 1674 break; 1675 1676 case IPOPT_LSRR: 1677 case IPOPT_SSRR: 1678 /* 1679 * user process specifies route as: 1680 * ->A->B->C->D 1681 * D must be our final destination (but we can't 1682 * check that since we may not have connected yet). 1683 * A is first hop destination, which doesn't appear in 1684 * actual IP option, but is stored before the options. 1685 */ 1686 if (optlen < IPOPT_MINOFF - 1 + sizeof(struct in_addr)) 1687 goto bad; 1688 m->m_len -= sizeof(struct in_addr); 1689 cnt -= sizeof(struct in_addr); 1690 optlen -= sizeof(struct in_addr); 1691 cp[IPOPT_OLEN] = optlen; 1692 /* 1693 * Move first hop before start of options. 1694 */ 1695 bcopy(&cp[IPOPT_OFFSET+1], mtod(m, caddr_t), 1696 sizeof(struct in_addr)); 1697 /* 1698 * Then copy rest of options back 1699 * to close up the deleted entry. 1700 */ 1701 ovbcopy(&cp[IPOPT_OFFSET+1] + sizeof(struct in_addr), 1702 &cp[IPOPT_OFFSET+1], 1703 cnt - (IPOPT_MINOFF - 1)); 1704 break; 1705 } 1706 } 1707 if (m->m_len > MAX_IPOPTLEN + sizeof(struct in_addr)) 1708 goto bad; 1709 *pcbopt = m; 1710 return (0); 1711 1712 bad: 1713 m_free(m); 1714 return (EINVAL); 1715 } 1716 1717 /* 1718 * XXX 1719 * The whole multicast option thing needs to be re-thought. 1720 * Several of these options are equally applicable to non-multicast 1721 * transmission, and one (IP_MULTICAST_TTL) totally duplicates a 1722 * standard option (IP_TTL). 1723 */ 1724 1725 /* 1726 * following RFC1724 section 3.3, 0.0.0.0/8 is interpreted as interface index. 1727 */ 1728 static struct ifnet * 1729 ip_multicast_if(struct in_addr *a, int *ifindexp) 1730 { 1731 int ifindex; 1732 struct ifnet *ifp; 1733 1734 if (ifindexp) 1735 *ifindexp = 0; 1736 if (ntohl(a->s_addr) >> 24 == 0) { 1737 ifindex = ntohl(a->s_addr) & 0xffffff; 1738 if (ifindex < 0 || if_index < ifindex) 1739 return NULL; 1740 ifp = ifindex2ifnet[ifindex]; 1741 if (ifindexp) 1742 *ifindexp = ifindex; 1743 } else { 1744 ifp = INADDR_TO_IFP(a); 1745 } 1746 return ifp; 1747 } 1748 1749 /* 1750 * Set the IP multicast options in response to user setsockopt(). 1751 */ 1752 static int 1753 ip_setmoptions(struct sockopt *sopt, struct ip_moptions **imop) 1754 { 1755 int error = 0; 1756 int i; 1757 struct in_addr addr; 1758 struct ip_mreq mreq; 1759 struct ifnet *ifp; 1760 struct ip_moptions *imo = *imop; 1761 int ifindex; 1762 1763 if (imo == NULL) { 1764 /* 1765 * No multicast option buffer attached to the pcb; 1766 * allocate one and initialize to default values. 1767 */ 1768 imo = kmalloc(sizeof *imo, M_IPMOPTS, M_WAITOK); 1769 1770 *imop = imo; 1771 imo->imo_multicast_ifp = NULL; 1772 imo->imo_multicast_addr.s_addr = INADDR_ANY; 1773 imo->imo_multicast_vif = -1; 1774 imo->imo_multicast_ttl = IP_DEFAULT_MULTICAST_TTL; 1775 imo->imo_multicast_loop = IP_DEFAULT_MULTICAST_LOOP; 1776 imo->imo_num_memberships = 0; 1777 } 1778 switch (sopt->sopt_name) { 1779 /* store an index number for the vif you wanna use in the send */ 1780 case IP_MULTICAST_VIF: 1781 if (legal_vif_num == 0) { 1782 error = EOPNOTSUPP; 1783 break; 1784 } 1785 error = soopt_to_kbuf(sopt, &i, sizeof i, sizeof i); 1786 if (error) 1787 break; 1788 if (!legal_vif_num(i) && (i != -1)) { 1789 error = EINVAL; 1790 break; 1791 } 1792 imo->imo_multicast_vif = i; 1793 break; 1794 1795 case IP_MULTICAST_IF: 1796 /* 1797 * Select the interface for outgoing multicast packets. 1798 */ 1799 error = soopt_to_kbuf(sopt, &addr, sizeof addr, sizeof addr); 1800 if (error) 1801 break; 1802 1803 /* 1804 * INADDR_ANY is used to remove a previous selection. 1805 * When no interface is selected, a default one is 1806 * chosen every time a multicast packet is sent. 1807 */ 1808 if (addr.s_addr == INADDR_ANY) { 1809 imo->imo_multicast_ifp = NULL; 1810 break; 1811 } 1812 /* 1813 * The selected interface is identified by its local 1814 * IP address. Find the interface and confirm that 1815 * it supports multicasting. 1816 */ 1817 crit_enter(); 1818 ifp = ip_multicast_if(&addr, &ifindex); 1819 if (ifp == NULL || !(ifp->if_flags & IFF_MULTICAST)) { 1820 crit_exit(); 1821 error = EADDRNOTAVAIL; 1822 break; 1823 } 1824 imo->imo_multicast_ifp = ifp; 1825 if (ifindex) 1826 imo->imo_multicast_addr = addr; 1827 else 1828 imo->imo_multicast_addr.s_addr = INADDR_ANY; 1829 crit_exit(); 1830 break; 1831 1832 case IP_MULTICAST_TTL: 1833 /* 1834 * Set the IP time-to-live for outgoing multicast packets. 1835 * The original multicast API required a char argument, 1836 * which is inconsistent with the rest of the socket API. 1837 * We allow either a char or an int. 1838 */ 1839 if (sopt->sopt_valsize == 1) { 1840 u_char ttl; 1841 error = soopt_to_kbuf(sopt, &ttl, 1, 1); 1842 if (error) 1843 break; 1844 imo->imo_multicast_ttl = ttl; 1845 } else { 1846 u_int ttl; 1847 error = soopt_to_kbuf(sopt, &ttl, sizeof ttl, sizeof ttl); 1848 if (error) 1849 break; 1850 if (ttl > 255) 1851 error = EINVAL; 1852 else 1853 imo->imo_multicast_ttl = ttl; 1854 } 1855 break; 1856 1857 case IP_MULTICAST_LOOP: 1858 /* 1859 * Set the loopback flag for outgoing multicast packets. 1860 * Must be zero or one. The original multicast API required a 1861 * char argument, which is inconsistent with the rest 1862 * of the socket API. We allow either a char or an int. 1863 */ 1864 if (sopt->sopt_valsize == 1) { 1865 u_char loop; 1866 1867 error = soopt_to_kbuf(sopt, &loop, 1, 1); 1868 if (error) 1869 break; 1870 imo->imo_multicast_loop = !!loop; 1871 } else { 1872 u_int loop; 1873 1874 error = soopt_to_kbuf(sopt, &loop, sizeof loop, 1875 sizeof loop); 1876 if (error) 1877 break; 1878 imo->imo_multicast_loop = !!loop; 1879 } 1880 break; 1881 1882 case IP_ADD_MEMBERSHIP: 1883 /* 1884 * Add a multicast group membership. 1885 * Group must be a valid IP multicast address. 1886 */ 1887 error = soopt_to_kbuf(sopt, &mreq, sizeof mreq, sizeof mreq); 1888 if (error) 1889 break; 1890 1891 if (!IN_MULTICAST(ntohl(mreq.imr_multiaddr.s_addr))) { 1892 error = EINVAL; 1893 break; 1894 } 1895 crit_enter(); 1896 /* 1897 * If no interface address was provided, use the interface of 1898 * the route to the given multicast address. 1899 */ 1900 if (mreq.imr_interface.s_addr == INADDR_ANY) { 1901 struct sockaddr_in dst; 1902 struct rtentry *rt; 1903 1904 bzero(&dst, sizeof(struct sockaddr_in)); 1905 dst.sin_len = sizeof(struct sockaddr_in); 1906 dst.sin_family = AF_INET; 1907 dst.sin_addr = mreq.imr_multiaddr; 1908 rt = rtlookup((struct sockaddr *)&dst); 1909 if (rt == NULL) { 1910 error = EADDRNOTAVAIL; 1911 crit_exit(); 1912 break; 1913 } 1914 --rt->rt_refcnt; 1915 ifp = rt->rt_ifp; 1916 } else { 1917 ifp = ip_multicast_if(&mreq.imr_interface, NULL); 1918 } 1919 1920 /* 1921 * See if we found an interface, and confirm that it 1922 * supports multicast. 1923 */ 1924 if (ifp == NULL || !(ifp->if_flags & IFF_MULTICAST)) { 1925 error = EADDRNOTAVAIL; 1926 crit_exit(); 1927 break; 1928 } 1929 /* 1930 * See if the membership already exists or if all the 1931 * membership slots are full. 1932 */ 1933 for (i = 0; i < imo->imo_num_memberships; ++i) { 1934 if (imo->imo_membership[i]->inm_ifp == ifp && 1935 imo->imo_membership[i]->inm_addr.s_addr 1936 == mreq.imr_multiaddr.s_addr) 1937 break; 1938 } 1939 if (i < imo->imo_num_memberships) { 1940 error = EADDRINUSE; 1941 crit_exit(); 1942 break; 1943 } 1944 if (i == IP_MAX_MEMBERSHIPS) { 1945 error = ETOOMANYREFS; 1946 crit_exit(); 1947 break; 1948 } 1949 /* 1950 * Everything looks good; add a new record to the multicast 1951 * address list for the given interface. 1952 */ 1953 if ((imo->imo_membership[i] = 1954 in_addmulti(&mreq.imr_multiaddr, ifp)) == NULL) { 1955 error = ENOBUFS; 1956 crit_exit(); 1957 break; 1958 } 1959 ++imo->imo_num_memberships; 1960 crit_exit(); 1961 break; 1962 1963 case IP_DROP_MEMBERSHIP: 1964 /* 1965 * Drop a multicast group membership. 1966 * Group must be a valid IP multicast address. 1967 */ 1968 error = soopt_to_kbuf(sopt, &mreq, sizeof mreq, sizeof mreq); 1969 if (error) 1970 break; 1971 1972 if (!IN_MULTICAST(ntohl(mreq.imr_multiaddr.s_addr))) { 1973 error = EINVAL; 1974 break; 1975 } 1976 1977 crit_enter(); 1978 /* 1979 * If an interface address was specified, get a pointer 1980 * to its ifnet structure. 1981 */ 1982 if (mreq.imr_interface.s_addr == INADDR_ANY) 1983 ifp = NULL; 1984 else { 1985 ifp = ip_multicast_if(&mreq.imr_interface, NULL); 1986 if (ifp == NULL) { 1987 error = EADDRNOTAVAIL; 1988 crit_exit(); 1989 break; 1990 } 1991 } 1992 /* 1993 * Find the membership in the membership array. 1994 */ 1995 for (i = 0; i < imo->imo_num_memberships; ++i) { 1996 if ((ifp == NULL || 1997 imo->imo_membership[i]->inm_ifp == ifp) && 1998 imo->imo_membership[i]->inm_addr.s_addr == 1999 mreq.imr_multiaddr.s_addr) 2000 break; 2001 } 2002 if (i == imo->imo_num_memberships) { 2003 error = EADDRNOTAVAIL; 2004 crit_exit(); 2005 break; 2006 } 2007 /* 2008 * Give up the multicast address record to which the 2009 * membership points. 2010 */ 2011 in_delmulti(imo->imo_membership[i]); 2012 /* 2013 * Remove the gap in the membership array. 2014 */ 2015 for (++i; i < imo->imo_num_memberships; ++i) 2016 imo->imo_membership[i-1] = imo->imo_membership[i]; 2017 --imo->imo_num_memberships; 2018 crit_exit(); 2019 break; 2020 2021 default: 2022 error = EOPNOTSUPP; 2023 break; 2024 } 2025 2026 /* 2027 * If all options have default values, no need to keep the mbuf. 2028 */ 2029 if (imo->imo_multicast_ifp == NULL && 2030 imo->imo_multicast_vif == -1 && 2031 imo->imo_multicast_ttl == IP_DEFAULT_MULTICAST_TTL && 2032 imo->imo_multicast_loop == IP_DEFAULT_MULTICAST_LOOP && 2033 imo->imo_num_memberships == 0) { 2034 kfree(*imop, M_IPMOPTS); 2035 *imop = NULL; 2036 } 2037 2038 return (error); 2039 } 2040 2041 /* 2042 * Return the IP multicast options in response to user getsockopt(). 2043 */ 2044 static int 2045 ip_getmoptions(struct sockopt *sopt, struct ip_moptions *imo) 2046 { 2047 struct in_addr addr; 2048 struct in_ifaddr *ia; 2049 int error, optval; 2050 u_char coptval; 2051 2052 error = 0; 2053 switch (sopt->sopt_name) { 2054 case IP_MULTICAST_VIF: 2055 if (imo != NULL) 2056 optval = imo->imo_multicast_vif; 2057 else 2058 optval = -1; 2059 soopt_from_kbuf(sopt, &optval, sizeof optval); 2060 break; 2061 2062 case IP_MULTICAST_IF: 2063 if (imo == NULL || imo->imo_multicast_ifp == NULL) 2064 addr.s_addr = INADDR_ANY; 2065 else if (imo->imo_multicast_addr.s_addr) { 2066 /* return the value user has set */ 2067 addr = imo->imo_multicast_addr; 2068 } else { 2069 ia = IFP_TO_IA(imo->imo_multicast_ifp); 2070 addr.s_addr = (ia == NULL) ? INADDR_ANY 2071 : IA_SIN(ia)->sin_addr.s_addr; 2072 } 2073 soopt_from_kbuf(sopt, &addr, sizeof addr); 2074 break; 2075 2076 case IP_MULTICAST_TTL: 2077 if (imo == NULL) 2078 optval = coptval = IP_DEFAULT_MULTICAST_TTL; 2079 else 2080 optval = coptval = imo->imo_multicast_ttl; 2081 if (sopt->sopt_valsize == 1) 2082 soopt_from_kbuf(sopt, &coptval, 1); 2083 else 2084 soopt_from_kbuf(sopt, &optval, sizeof optval); 2085 break; 2086 2087 case IP_MULTICAST_LOOP: 2088 if (imo == NULL) 2089 optval = coptval = IP_DEFAULT_MULTICAST_LOOP; 2090 else 2091 optval = coptval = imo->imo_multicast_loop; 2092 if (sopt->sopt_valsize == 1) 2093 soopt_from_kbuf(sopt, &coptval, 1); 2094 else 2095 soopt_from_kbuf(sopt, &optval, sizeof optval); 2096 break; 2097 2098 default: 2099 error = ENOPROTOOPT; 2100 break; 2101 } 2102 return (error); 2103 } 2104 2105 /* 2106 * Discard the IP multicast options. 2107 */ 2108 void 2109 ip_freemoptions(struct ip_moptions *imo) 2110 { 2111 int i; 2112 2113 if (imo != NULL) { 2114 for (i = 0; i < imo->imo_num_memberships; ++i) 2115 in_delmulti(imo->imo_membership[i]); 2116 kfree(imo, M_IPMOPTS); 2117 } 2118 } 2119 2120 /* 2121 * Routine called from ip_output() to loop back a copy of an IP multicast 2122 * packet to the input queue of a specified interface. Note that this 2123 * calls the output routine of the loopback "driver", but with an interface 2124 * pointer that might NOT be a loopback interface -- evil, but easier than 2125 * replicating that code here. 2126 */ 2127 static void 2128 ip_mloopback(struct ifnet *ifp, struct mbuf *m, struct sockaddr_in *dst, 2129 int hlen) 2130 { 2131 struct ip *ip; 2132 struct mbuf *copym; 2133 2134 copym = m_copypacket(m, MB_DONTWAIT); 2135 if (copym != NULL && (copym->m_flags & M_EXT || copym->m_len < hlen)) 2136 copym = m_pullup(copym, hlen); 2137 if (copym != NULL) { 2138 /* 2139 * if the checksum hasn't been computed, mark it as valid 2140 */ 2141 if (copym->m_pkthdr.csum_flags & CSUM_DELAY_DATA) { 2142 in_delayed_cksum(copym); 2143 copym->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA; 2144 copym->m_pkthdr.csum_flags |= 2145 CSUM_DATA_VALID | CSUM_PSEUDO_HDR; 2146 copym->m_pkthdr.csum_data = 0xffff; 2147 } 2148 /* 2149 * We don't bother to fragment if the IP length is greater 2150 * than the interface's MTU. Can this possibly matter? 2151 */ 2152 ip = mtod(copym, struct ip *); 2153 ip->ip_len = htons(ip->ip_len); 2154 ip->ip_off = htons(ip->ip_off); 2155 ip->ip_sum = 0; 2156 if (ip->ip_vhl == IP_VHL_BORING) { 2157 ip->ip_sum = in_cksum_hdr(ip); 2158 } else { 2159 ip->ip_sum = in_cksum(copym, hlen); 2160 } 2161 /* 2162 * NB: 2163 * It's not clear whether there are any lingering 2164 * reentrancy problems in other areas which might 2165 * be exposed by using ip_input directly (in 2166 * particular, everything which modifies the packet 2167 * in-place). Yet another option is using the 2168 * protosw directly to deliver the looped back 2169 * packet. For the moment, we'll err on the side 2170 * of safety by using if_simloop(). 2171 */ 2172 #if 1 /* XXX */ 2173 if (dst->sin_family != AF_INET) { 2174 kprintf("ip_mloopback: bad address family %d\n", 2175 dst->sin_family); 2176 dst->sin_family = AF_INET; 2177 } 2178 #endif 2179 if_simloop(ifp, copym, dst->sin_family, 0); 2180 } 2181 } 2182