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/priv.h> 54 #include <sys/sysctl.h> 55 #include <sys/in_cksum.h> 56 #include <sys/lock.h> 57 58 #include <sys/thread2.h> 59 #include <sys/mplock2.h> 60 #include <sys/msgport2.h> 61 62 #include <net/if.h> 63 #include <net/netisr.h> 64 #include <net/pfil.h> 65 #include <net/route.h> 66 67 #include <netinet/in.h> 68 #include <netinet/in_systm.h> 69 #include <netinet/ip.h> 70 #include <netinet/in_pcb.h> 71 #include <netinet/in_var.h> 72 #include <netinet/ip_var.h> 73 74 #include <netproto/mpls/mpls_var.h> 75 76 static MALLOC_DEFINE(M_IPMOPTS, "ip_moptions", "internet multicast options"); 77 78 #ifdef IPSEC 79 #include <netinet6/ipsec.h> 80 #include <netproto/key/key.h> 81 #ifdef IPSEC_DEBUG 82 #include <netproto/key/key_debug.h> 83 #else 84 #define KEYDEBUG(lev,arg) 85 #endif 86 #endif /*IPSEC*/ 87 88 #ifdef FAST_IPSEC 89 #include <netproto/ipsec/ipsec.h> 90 #include <netproto/ipsec/xform.h> 91 #include <netproto/ipsec/key.h> 92 #endif /*FAST_IPSEC*/ 93 94 #include <net/ipfw/ip_fw.h> 95 #include <net/dummynet/ip_dummynet.h> 96 97 #define print_ip(x, a, y) kprintf("%s %d.%d.%d.%d%s",\ 98 x, (ntohl(a.s_addr)>>24)&0xFF,\ 99 (ntohl(a.s_addr)>>16)&0xFF,\ 100 (ntohl(a.s_addr)>>8)&0xFF,\ 101 (ntohl(a.s_addr))&0xFF, y); 102 103 u_short ip_id; 104 105 #ifdef MBUF_STRESS_TEST 106 int mbuf_frag_size = 0; 107 SYSCTL_INT(_net_inet_ip, OID_AUTO, mbuf_frag_size, CTLFLAG_RW, 108 &mbuf_frag_size, 0, "Fragment outgoing mbufs to this size"); 109 #endif 110 111 static struct mbuf *ip_insertoptions(struct mbuf *, struct mbuf *, int *); 112 static struct ifnet *ip_multicast_if(struct in_addr *, int *); 113 static void ip_mloopback 114 (struct ifnet *, struct mbuf *, struct sockaddr_in *, int); 115 static int ip_getmoptions 116 (struct sockopt *, struct ip_moptions *); 117 static int ip_pcbopts(int, struct mbuf **, struct mbuf *); 118 static int ip_setmoptions 119 (struct sockopt *, struct ip_moptions **); 120 121 int ip_optcopy(struct ip *, struct ip *); 122 123 extern int route_assert_owner_access; 124 125 extern struct protosw inetsw[]; 126 127 static int 128 ip_localforward(struct mbuf *m, const struct sockaddr_in *dst, int hlen) 129 { 130 struct in_ifaddr_container *iac; 131 132 /* 133 * We need to figure out if we have been forwarded to a local 134 * socket. If so, then we should somehow "loop back" to 135 * ip_input(), and get directed to the PCB as if we had received 136 * this packet. This is because it may be difficult to identify 137 * the packets you want to forward until they are being output 138 * and have selected an interface (e.g. locally initiated 139 * packets). If we used the loopback inteface, we would not be 140 * able to control what happens as the packet runs through 141 * ip_input() as it is done through a ISR. 142 */ 143 LIST_FOREACH(iac, INADDR_HASH(dst->sin_addr.s_addr), ia_hash) { 144 /* 145 * If the addr to forward to is one of ours, we pretend 146 * to be the destination for this packet. 147 */ 148 if (IA_SIN(iac->ia)->sin_addr.s_addr == dst->sin_addr.s_addr) 149 break; 150 } 151 if (iac != NULL) { 152 struct ip *ip; 153 154 if (m->m_pkthdr.rcvif == NULL) 155 m->m_pkthdr.rcvif = ifunit("lo0"); 156 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) { 157 m->m_pkthdr.csum_flags |= CSUM_DATA_VALID | 158 CSUM_PSEUDO_HDR; 159 m->m_pkthdr.csum_data = 0xffff; 160 } 161 m->m_pkthdr.csum_flags |= CSUM_IP_CHECKED | CSUM_IP_VALID; 162 163 /* 164 * Make sure that the IP header is in one mbuf, 165 * required by ip_input 166 */ 167 if (m->m_len < hlen) { 168 m = m_pullup(m, hlen); 169 if (m == NULL) { 170 /* The packet was freed; we are done */ 171 return 1; 172 } 173 } 174 ip = mtod(m, struct ip *); 175 176 ip->ip_len = htons(ip->ip_len); 177 ip->ip_off = htons(ip->ip_off); 178 ip_input(m); 179 180 return 1; /* The packet gets forwarded locally */ 181 } 182 return 0; 183 } 184 185 /* 186 * IP output. The packet in mbuf chain m contains a skeletal IP 187 * header (with len, off, ttl, proto, tos, src, dst). 188 * The mbuf chain containing the packet will be freed. 189 * The mbuf opt, if present, will not be freed. 190 */ 191 int 192 ip_output(struct mbuf *m0, struct mbuf *opt, struct route *ro, 193 int flags, struct ip_moptions *imo, struct inpcb *inp) 194 { 195 struct ip *ip; 196 struct ifnet *ifp = NULL; /* keep compiler happy */ 197 struct mbuf *m; 198 int hlen = sizeof(struct ip); 199 int len, error = 0; 200 struct sockaddr_in *dst = NULL; /* keep compiler happy */ 201 struct in_ifaddr *ia = NULL; 202 int isbroadcast, sw_csum; 203 struct in_addr pkt_dst; 204 struct route iproute; 205 struct m_tag *mtag; 206 #ifdef IPSEC 207 struct secpolicy *sp = NULL; 208 struct socket *so = inp ? inp->inp_socket : NULL; 209 #endif 210 #ifdef FAST_IPSEC 211 struct secpolicy *sp = NULL; 212 struct tdb_ident *tdbi; 213 #endif /* FAST_IPSEC */ 214 struct sockaddr_in *next_hop = NULL; 215 int src_was_INADDR_ANY = 0; /* as the name says... */ 216 217 m = m0; 218 M_ASSERTPKTHDR(m); 219 220 if (ro == NULL) { 221 ro = &iproute; 222 bzero(ro, sizeof *ro); 223 } else if (ro->ro_rt != NULL && ro->ro_rt->rt_cpuid != mycpuid) { 224 if (flags & IP_DEBUGROUTE) { 225 if (route_assert_owner_access) { 226 panic("ip_output: " 227 "rt rt_cpuid %d accessed on cpu %d\n", 228 ro->ro_rt->rt_cpuid, mycpuid); 229 } else { 230 kprintf("ip_output: " 231 "rt rt_cpuid %d accessed on cpu %d\n", 232 ro->ro_rt->rt_cpuid, mycpuid); 233 print_backtrace(-1); 234 } 235 } 236 237 /* 238 * XXX 239 * If the cached rtentry's owner CPU is not the current CPU, 240 * then don't touch the cached rtentry (remote free is too 241 * expensive in this context); just relocate the route. 242 */ 243 ro = &iproute; 244 bzero(ro, sizeof *ro); 245 } 246 247 if (m->m_pkthdr.fw_flags & IPFORWARD_MBUF_TAGGED) { 248 /* Next hop */ 249 mtag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL); 250 KKASSERT(mtag != NULL); 251 next_hop = m_tag_data(mtag); 252 } 253 254 if (m->m_pkthdr.fw_flags & DUMMYNET_MBUF_TAGGED) { 255 struct dn_pkt *dn_pkt; 256 257 /* Extract info from dummynet tag */ 258 mtag = m_tag_find(m, PACKET_TAG_DUMMYNET, NULL); 259 KKASSERT(mtag != NULL); 260 dn_pkt = m_tag_data(mtag); 261 262 /* 263 * The packet was already tagged, so part of the 264 * processing was already done, and we need to go down. 265 * Get the calculated parameters from the tag. 266 */ 267 ifp = dn_pkt->ifp; 268 269 KKASSERT(ro == &iproute); 270 *ro = dn_pkt->ro; /* structure copy */ 271 KKASSERT(ro->ro_rt == NULL || ro->ro_rt->rt_cpuid == mycpuid); 272 273 dst = dn_pkt->dn_dst; 274 if (dst == (struct sockaddr_in *)&(dn_pkt->ro.ro_dst)) { 275 /* If 'dst' points into dummynet tag, adjust it */ 276 dst = (struct sockaddr_in *)&(ro->ro_dst); 277 } 278 279 ip = mtod(m, struct ip *); 280 hlen = IP_VHL_HL(ip->ip_vhl) << 2 ; 281 if (ro->ro_rt) 282 ia = ifatoia(ro->ro_rt->rt_ifa); 283 goto sendit; 284 } 285 286 if (opt) { 287 len = 0; 288 m = ip_insertoptions(m, opt, &len); 289 if (len != 0) 290 hlen = len; 291 } 292 ip = mtod(m, struct ip *); 293 294 /* 295 * Fill in IP header. 296 */ 297 if (!(flags & (IP_FORWARDING|IP_RAWOUTPUT))) { 298 ip->ip_vhl = IP_MAKE_VHL(IPVERSION, hlen >> 2); 299 ip->ip_off &= IP_DF; 300 ip->ip_id = ip_newid(); 301 ipstat.ips_localout++; 302 } else { 303 hlen = IP_VHL_HL(ip->ip_vhl) << 2; 304 } 305 306 reroute: 307 pkt_dst = next_hop ? next_hop->sin_addr : ip->ip_dst; 308 309 #ifdef INVARIANTS 310 if (IN_MULTICAST(ntohl(pkt_dst.s_addr))) { 311 /* 312 * XXX 313 * Multicast is not MPSAFE yet. Caller must hold 314 * BGL when output a multicast IP packet. 315 */ 316 ASSERT_MP_LOCK_HELD(curthread); 317 } 318 #endif 319 320 dst = (struct sockaddr_in *)&ro->ro_dst; 321 /* 322 * If there is a cached route, 323 * check that it is to the same destination 324 * and is still up. If not, free it and try again. 325 * The address family should also be checked in case of sharing the 326 * cache with IPv6. 327 */ 328 if (ro->ro_rt && 329 (!(ro->ro_rt->rt_flags & RTF_UP) || 330 dst->sin_family != AF_INET || 331 dst->sin_addr.s_addr != pkt_dst.s_addr)) { 332 rtfree(ro->ro_rt); 333 ro->ro_rt = NULL; 334 } 335 if (ro->ro_rt == NULL) { 336 bzero(dst, sizeof *dst); 337 dst->sin_family = AF_INET; 338 dst->sin_len = sizeof *dst; 339 dst->sin_addr = pkt_dst; 340 } 341 /* 342 * If routing to interface only, 343 * short circuit routing lookup. 344 */ 345 if (flags & IP_ROUTETOIF) { 346 if ((ia = ifatoia(ifa_ifwithdstaddr(sintosa(dst)))) == NULL && 347 (ia = ifatoia(ifa_ifwithnet(sintosa(dst)))) == NULL) { 348 ipstat.ips_noroute++; 349 error = ENETUNREACH; 350 goto bad; 351 } 352 ifp = ia->ia_ifp; 353 ip->ip_ttl = 1; 354 isbroadcast = in_broadcast(dst->sin_addr, ifp); 355 } else if (IN_MULTICAST(ntohl(pkt_dst.s_addr)) && 356 imo != NULL && imo->imo_multicast_ifp != NULL) { 357 /* 358 * Bypass the normal routing lookup for multicast 359 * packets if the interface is specified. 360 */ 361 ifp = imo->imo_multicast_ifp; 362 ia = IFP_TO_IA(ifp); 363 isbroadcast = 0; /* fool gcc */ 364 } else { 365 /* 366 * If this is the case, we probably don't want to allocate 367 * a protocol-cloned route since we didn't get one from the 368 * ULP. This lets TCP do its thing, while not burdening 369 * forwarding or ICMP with the overhead of cloning a route. 370 * Of course, we still want to do any cloning requested by 371 * the link layer, as this is probably required in all cases 372 * for correct operation (as it is for ARP). 373 */ 374 if (ro->ro_rt == NULL) 375 rtalloc_ign(ro, RTF_PRCLONING); 376 if (ro->ro_rt == NULL) { 377 ipstat.ips_noroute++; 378 error = EHOSTUNREACH; 379 goto bad; 380 } 381 ia = ifatoia(ro->ro_rt->rt_ifa); 382 ifp = ro->ro_rt->rt_ifp; 383 ro->ro_rt->rt_use++; 384 if (ro->ro_rt->rt_flags & RTF_GATEWAY) 385 dst = (struct sockaddr_in *)ro->ro_rt->rt_gateway; 386 if (ro->ro_rt->rt_flags & RTF_HOST) 387 isbroadcast = (ro->ro_rt->rt_flags & RTF_BROADCAST); 388 else 389 isbroadcast = in_broadcast(dst->sin_addr, ifp); 390 } 391 if (IN_MULTICAST(ntohl(pkt_dst.s_addr))) { 392 struct in_multi *inm; 393 394 m->m_flags |= M_MCAST; 395 /* 396 * IP destination address is multicast. Make sure "dst" 397 * still points to the address in "ro". (It may have been 398 * changed to point to a gateway address, above.) 399 */ 400 dst = (struct sockaddr_in *)&ro->ro_dst; 401 /* 402 * See if the caller provided any multicast options 403 */ 404 if (imo != NULL) { 405 ip->ip_ttl = imo->imo_multicast_ttl; 406 if (imo->imo_multicast_vif != -1) { 407 ip->ip_src.s_addr = 408 ip_mcast_src ? 409 ip_mcast_src(imo->imo_multicast_vif) : 410 INADDR_ANY; 411 } 412 } else { 413 ip->ip_ttl = IP_DEFAULT_MULTICAST_TTL; 414 } 415 /* 416 * Confirm that the outgoing interface supports multicast. 417 */ 418 if ((imo == NULL) || (imo->imo_multicast_vif == -1)) { 419 if (!(ifp->if_flags & IFF_MULTICAST)) { 420 ipstat.ips_noroute++; 421 error = ENETUNREACH; 422 goto bad; 423 } 424 } 425 /* 426 * If source address not specified yet, use address 427 * of outgoing interface. 428 */ 429 if (ip->ip_src.s_addr == INADDR_ANY) { 430 /* Interface may have no addresses. */ 431 if (ia != NULL) 432 ip->ip_src = IA_SIN(ia)->sin_addr; 433 } 434 435 IN_LOOKUP_MULTI(pkt_dst, ifp, inm); 436 if (inm != NULL && 437 (imo == NULL || imo->imo_multicast_loop)) { 438 /* 439 * If we belong to the destination multicast group 440 * on the outgoing interface, and the caller did not 441 * forbid loopback, loop back a copy. 442 */ 443 ip_mloopback(ifp, m, dst, hlen); 444 } else { 445 /* 446 * If we are acting as a multicast router, perform 447 * multicast forwarding as if the packet had just 448 * arrived on the interface to which we are about 449 * to send. The multicast forwarding function 450 * recursively calls this function, using the 451 * IP_FORWARDING flag to prevent infinite recursion. 452 * 453 * Multicasts that are looped back by ip_mloopback(), 454 * above, will be forwarded by the ip_input() routine, 455 * if necessary. 456 */ 457 if (ip_mrouter && !(flags & IP_FORWARDING)) { 458 /* 459 * If rsvp daemon is not running, do not 460 * set ip_moptions. This ensures that the packet 461 * is multicast and not just sent down one link 462 * as prescribed by rsvpd. 463 */ 464 if (!rsvp_on) 465 imo = NULL; 466 if (ip_mforward && 467 ip_mforward(ip, ifp, m, imo) != 0) { 468 m_freem(m); 469 goto done; 470 } 471 } 472 } 473 474 /* 475 * Multicasts with a time-to-live of zero may be looped- 476 * back, above, but must not be transmitted on a network. 477 * Also, multicasts addressed to the loopback interface 478 * are not sent -- the above call to ip_mloopback() will 479 * loop back a copy if this host actually belongs to the 480 * destination group on the loopback interface. 481 */ 482 if (ip->ip_ttl == 0 || ifp->if_flags & IFF_LOOPBACK) { 483 m_freem(m); 484 goto done; 485 } 486 487 goto sendit; 488 } else { 489 m->m_flags &= ~M_MCAST; 490 } 491 492 /* 493 * If the source address is not specified yet, use the address 494 * of the outoing interface. In case, keep note we did that, so 495 * if the the firewall changes the next-hop causing the output 496 * interface to change, we can fix that. 497 */ 498 if (ip->ip_src.s_addr == INADDR_ANY || src_was_INADDR_ANY) { 499 /* Interface may have no addresses. */ 500 if (ia != NULL) { 501 ip->ip_src = IA_SIN(ia)->sin_addr; 502 src_was_INADDR_ANY = 1; 503 } 504 } 505 506 #ifdef ALTQ 507 /* 508 * Disable packet drop hack. 509 * Packetdrop should be done by queueing. 510 */ 511 #else /* !ALTQ */ 512 /* 513 * Verify that we have any chance at all of being able to queue 514 * the packet or packet fragments 515 */ 516 if ((ifp->if_snd.ifq_len + ip->ip_len / ifp->if_mtu + 1) >= 517 ifp->if_snd.ifq_maxlen) { 518 error = ENOBUFS; 519 ipstat.ips_odropped++; 520 goto bad; 521 } 522 #endif /* !ALTQ */ 523 524 /* 525 * Look for broadcast address and 526 * verify user is allowed to send 527 * such a packet. 528 */ 529 if (isbroadcast) { 530 if (!(ifp->if_flags & IFF_BROADCAST)) { 531 error = EADDRNOTAVAIL; 532 goto bad; 533 } 534 if (!(flags & IP_ALLOWBROADCAST)) { 535 error = EACCES; 536 goto bad; 537 } 538 /* don't allow broadcast messages to be fragmented */ 539 if (ip->ip_len > ifp->if_mtu) { 540 error = EMSGSIZE; 541 goto bad; 542 } 543 m->m_flags |= M_BCAST; 544 } else { 545 m->m_flags &= ~M_BCAST; 546 } 547 548 sendit: 549 #ifdef IPSEC 550 /* get SP for this packet */ 551 if (so == NULL) 552 sp = ipsec4_getpolicybyaddr(m, IPSEC_DIR_OUTBOUND, flags, &error); 553 else 554 sp = ipsec4_getpolicybysock(m, IPSEC_DIR_OUTBOUND, so, &error); 555 556 if (sp == NULL) { 557 ipsecstat.out_inval++; 558 goto bad; 559 } 560 561 error = 0; 562 563 /* check policy */ 564 switch (sp->policy) { 565 case IPSEC_POLICY_DISCARD: 566 /* 567 * This packet is just discarded. 568 */ 569 ipsecstat.out_polvio++; 570 goto bad; 571 572 case IPSEC_POLICY_BYPASS: 573 case IPSEC_POLICY_NONE: 574 case IPSEC_POLICY_TCP: 575 /* no need to do IPsec. */ 576 goto skip_ipsec; 577 578 case IPSEC_POLICY_IPSEC: 579 if (sp->req == NULL) { 580 /* acquire a policy */ 581 error = key_spdacquire(sp); 582 goto bad; 583 } 584 break; 585 586 case IPSEC_POLICY_ENTRUST: 587 default: 588 kprintf("ip_output: Invalid policy found. %d\n", sp->policy); 589 } 590 { 591 struct ipsec_output_state state; 592 bzero(&state, sizeof state); 593 state.m = m; 594 if (flags & IP_ROUTETOIF) { 595 state.ro = &iproute; 596 bzero(&iproute, sizeof iproute); 597 } else 598 state.ro = ro; 599 state.dst = (struct sockaddr *)dst; 600 601 ip->ip_sum = 0; 602 603 /* 604 * XXX 605 * delayed checksums are not currently compatible with IPsec 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 error = ipsec4_output(&state, sp, flags); 616 617 m = state.m; 618 if (flags & IP_ROUTETOIF) { 619 /* 620 * if we have tunnel mode SA, we may need to ignore 621 * IP_ROUTETOIF. 622 */ 623 if (state.ro != &iproute || state.ro->ro_rt != NULL) { 624 flags &= ~IP_ROUTETOIF; 625 ro = state.ro; 626 } 627 } else 628 ro = state.ro; 629 dst = (struct sockaddr_in *)state.dst; 630 if (error) { 631 /* mbuf is already reclaimed in ipsec4_output. */ 632 m0 = NULL; 633 switch (error) { 634 case EHOSTUNREACH: 635 case ENETUNREACH: 636 case EMSGSIZE: 637 case ENOBUFS: 638 case ENOMEM: 639 break; 640 default: 641 kprintf("ip4_output (ipsec): error code %d\n", error); 642 /*fall through*/ 643 case ENOENT: 644 /* don't show these error codes to the user */ 645 error = 0; 646 break; 647 } 648 goto bad; 649 } 650 } 651 652 /* be sure to update variables that are affected by ipsec4_output() */ 653 ip = mtod(m, struct ip *); 654 #ifdef _IP_VHL 655 hlen = IP_VHL_HL(ip->ip_vhl) << 2; 656 #else 657 hlen = ip->ip_hl << 2; 658 #endif 659 if (ro->ro_rt == NULL) { 660 if (!(flags & IP_ROUTETOIF)) { 661 kprintf("ip_output: " 662 "can't update route after IPsec processing\n"); 663 error = EHOSTUNREACH; /*XXX*/ 664 goto bad; 665 } 666 } else { 667 ia = ifatoia(ro->ro_rt->rt_ifa); 668 ifp = ro->ro_rt->rt_ifp; 669 } 670 671 /* make it flipped, again. */ 672 ip->ip_len = ntohs(ip->ip_len); 673 ip->ip_off = ntohs(ip->ip_off); 674 skip_ipsec: 675 #endif /*IPSEC*/ 676 #ifdef FAST_IPSEC 677 /* 678 * Check the security policy (SP) for the packet and, if 679 * required, do IPsec-related processing. There are two 680 * cases here; the first time a packet is sent through 681 * it will be untagged and handled by ipsec4_checkpolicy. 682 * If the packet is resubmitted to ip_output (e.g. after 683 * AH, ESP, etc. processing), there will be a tag to bypass 684 * the lookup and related policy checking. 685 */ 686 mtag = m_tag_find(m, PACKET_TAG_IPSEC_PENDING_TDB, NULL); 687 crit_enter(); 688 if (mtag != NULL) { 689 tdbi = (struct tdb_ident *)m_tag_data(mtag); 690 sp = ipsec_getpolicy(tdbi, IPSEC_DIR_OUTBOUND); 691 if (sp == NULL) 692 error = -EINVAL; /* force silent drop */ 693 m_tag_delete(m, mtag); 694 } else { 695 sp = ipsec4_checkpolicy(m, IPSEC_DIR_OUTBOUND, flags, 696 &error, inp); 697 } 698 /* 699 * There are four return cases: 700 * sp != NULL apply IPsec policy 701 * sp == NULL, error == 0 no IPsec handling needed 702 * sp == NULL, error == -EINVAL discard packet w/o error 703 * sp == NULL, error != 0 discard packet, report error 704 */ 705 if (sp != NULL) { 706 /* Loop detection, check if ipsec processing already done */ 707 KASSERT(sp->req != NULL, ("ip_output: no ipsec request")); 708 for (mtag = m_tag_first(m); mtag != NULL; 709 mtag = m_tag_next(m, mtag)) { 710 if (mtag->m_tag_cookie != MTAG_ABI_COMPAT) 711 continue; 712 if (mtag->m_tag_id != PACKET_TAG_IPSEC_OUT_DONE && 713 mtag->m_tag_id != PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED) 714 continue; 715 /* 716 * Check if policy has an SA associated with it. 717 * This can happen when an SP has yet to acquire 718 * an SA; e.g. on first reference. If it occurs, 719 * then we let ipsec4_process_packet do its thing. 720 */ 721 if (sp->req->sav == NULL) 722 break; 723 tdbi = (struct tdb_ident *)m_tag_data(mtag); 724 if (tdbi->spi == sp->req->sav->spi && 725 tdbi->proto == sp->req->sav->sah->saidx.proto && 726 bcmp(&tdbi->dst, &sp->req->sav->sah->saidx.dst, 727 sizeof(union sockaddr_union)) == 0) { 728 /* 729 * No IPsec processing is needed, free 730 * reference to SP. 731 * 732 * NB: null pointer to avoid free at 733 * done: below. 734 */ 735 KEY_FREESP(&sp), sp = NULL; 736 crit_exit(); 737 goto spd_done; 738 } 739 } 740 741 /* 742 * Do delayed checksums now because we send before 743 * this is done in the normal processing path. 744 */ 745 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) { 746 in_delayed_cksum(m); 747 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA; 748 } 749 750 ip->ip_len = htons(ip->ip_len); 751 ip->ip_off = htons(ip->ip_off); 752 753 /* NB: callee frees mbuf */ 754 error = ipsec4_process_packet(m, sp->req, flags, 0); 755 /* 756 * Preserve KAME behaviour: ENOENT can be returned 757 * when an SA acquire is in progress. Don't propagate 758 * this to user-level; it confuses applications. 759 * 760 * XXX this will go away when the SADB is redone. 761 */ 762 if (error == ENOENT) 763 error = 0; 764 crit_exit(); 765 goto done; 766 } else { 767 crit_exit(); 768 769 if (error != 0) { 770 /* 771 * Hack: -EINVAL is used to signal that a packet 772 * should be silently discarded. This is typically 773 * because we asked key management for an SA and 774 * it was delayed (e.g. kicked up to IKE). 775 */ 776 if (error == -EINVAL) 777 error = 0; 778 goto bad; 779 } else { 780 /* No IPsec processing for this packet. */ 781 } 782 #ifdef notyet 783 /* 784 * If deferred crypto processing is needed, check that 785 * the interface supports it. 786 */ 787 mtag = m_tag_find(m, PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED, NULL); 788 if (mtag != NULL && !(ifp->if_capenable & IFCAP_IPSEC)) { 789 /* notify IPsec to do its own crypto */ 790 ipsp_skipcrypto_unmark((struct tdb_ident *)m_tag_data(mtag)); 791 error = EHOSTUNREACH; 792 goto bad; 793 } 794 #endif 795 } 796 spd_done: 797 #endif /* FAST_IPSEC */ 798 799 /* We are already being fwd'd from a firewall. */ 800 if (next_hop != NULL) 801 goto pass; 802 803 /* No pfil hooks */ 804 if (!pfil_has_hooks(&inet_pfil_hook)) { 805 if (m->m_pkthdr.fw_flags & DUMMYNET_MBUF_TAGGED) { 806 /* 807 * Strip dummynet tags from stranded packets 808 */ 809 mtag = m_tag_find(m, PACKET_TAG_DUMMYNET, NULL); 810 KKASSERT(mtag != NULL); 811 m_tag_delete(m, mtag); 812 m->m_pkthdr.fw_flags &= ~DUMMYNET_MBUF_TAGGED; 813 } 814 goto pass; 815 } 816 817 /* 818 * IpHack's section. 819 * - Xlate: translate packet's addr/port (NAT). 820 * - Firewall: deny/allow/etc. 821 * - Wrap: fake packet's addr/port <unimpl.> 822 * - Encapsulate: put it in another IP and send out. <unimp.> 823 */ 824 825 /* 826 * Run through list of hooks for output packets. 827 */ 828 error = pfil_run_hooks(&inet_pfil_hook, &m, ifp, PFIL_OUT); 829 if (error != 0 || m == NULL) 830 goto done; 831 ip = mtod(m, struct ip *); 832 833 if (m->m_pkthdr.fw_flags & IPFORWARD_MBUF_TAGGED) { 834 /* 835 * Check dst to make sure it is directly reachable on the 836 * interface we previously thought it was. 837 * If it isn't (which may be likely in some situations) we have 838 * to re-route it (ie, find a route for the next-hop and the 839 * associated interface) and set them here. This is nested 840 * forwarding which in most cases is undesirable, except where 841 * such control is nigh impossible. So we do it here. 842 * And I'm babbling. 843 */ 844 mtag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL); 845 KKASSERT(mtag != NULL); 846 next_hop = m_tag_data(mtag); 847 848 /* 849 * Try local forwarding first 850 */ 851 if (ip_localforward(m, next_hop, hlen)) 852 goto done; 853 854 /* 855 * Relocate the route based on next_hop. 856 * If the current route is inp's cache, keep it untouched. 857 */ 858 if (ro == &iproute && ro->ro_rt != NULL) { 859 RTFREE(ro->ro_rt); 860 ro->ro_rt = NULL; 861 } 862 ro = &iproute; 863 bzero(ro, sizeof *ro); 864 865 /* 866 * Forwarding to broadcast address is not allowed. 867 * XXX Should we follow IP_ROUTETOIF? 868 */ 869 flags &= ~(IP_ALLOWBROADCAST | IP_ROUTETOIF); 870 871 /* We are doing forwarding now */ 872 flags |= IP_FORWARDING; 873 874 goto reroute; 875 } 876 877 if (m->m_pkthdr.fw_flags & DUMMYNET_MBUF_TAGGED) { 878 struct dn_pkt *dn_pkt; 879 880 mtag = m_tag_find(m, PACKET_TAG_DUMMYNET, NULL); 881 KKASSERT(mtag != NULL); 882 dn_pkt = m_tag_data(mtag); 883 884 /* 885 * Under certain cases it is not possible to recalculate 886 * 'ro' and 'dst', let alone 'flags', so just save them in 887 * dummynet tag and avoid the possible wrong reculcalation 888 * when we come back to ip_output() again. 889 * 890 * All other parameters have been already used and so they 891 * are not needed anymore. 892 * XXX if the ifp is deleted while a pkt is in dummynet, 893 * we are in trouble! (TODO use ifnet_detach_event) 894 * 895 * We need to copy *ro because for ICMP pkts (and maybe 896 * others) the caller passed a pointer into the stack; 897 * dst might also be a pointer into *ro so it needs to 898 * be updated. 899 */ 900 dn_pkt->ro = *ro; 901 if (ro->ro_rt) 902 ro->ro_rt->rt_refcnt++; 903 if (dst == (struct sockaddr_in *)&ro->ro_dst) { 904 /* 'dst' points into 'ro' */ 905 dst = (struct sockaddr_in *)&(dn_pkt->ro.ro_dst); 906 } 907 dn_pkt->dn_dst = dst; 908 dn_pkt->flags = flags; 909 910 ip_dn_queue(m); 911 goto done; 912 } 913 pass: 914 /* 127/8 must not appear on wire - RFC1122. */ 915 if ((ntohl(ip->ip_dst.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET || 916 (ntohl(ip->ip_src.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET) { 917 if (!(ifp->if_flags & IFF_LOOPBACK)) { 918 ipstat.ips_badaddr++; 919 error = EADDRNOTAVAIL; 920 goto bad; 921 } 922 } 923 924 m->m_pkthdr.csum_flags |= CSUM_IP; 925 sw_csum = m->m_pkthdr.csum_flags & ~ifp->if_hwassist; 926 if (sw_csum & CSUM_DELAY_DATA) { 927 in_delayed_cksum(m); 928 sw_csum &= ~CSUM_DELAY_DATA; 929 } 930 m->m_pkthdr.csum_flags &= ifp->if_hwassist; 931 932 /* 933 * If small enough for interface, or the interface will take 934 * care of the fragmentation for us, can just send directly. 935 */ 936 if (ip->ip_len <= ifp->if_mtu || ((ifp->if_hwassist & CSUM_FRAGMENT) && 937 !(ip->ip_off & IP_DF))) { 938 ip->ip_len = htons(ip->ip_len); 939 ip->ip_off = htons(ip->ip_off); 940 ip->ip_sum = 0; 941 if (sw_csum & CSUM_DELAY_IP) { 942 if (ip->ip_vhl == IP_VHL_BORING) 943 ip->ip_sum = in_cksum_hdr(ip); 944 else 945 ip->ip_sum = in_cksum(m, hlen); 946 } 947 948 /* Record statistics for this interface address. */ 949 if (!(flags & IP_FORWARDING) && ia) { 950 ia->ia_ifa.if_opackets++; 951 ia->ia_ifa.if_obytes += m->m_pkthdr.len; 952 } 953 954 #ifdef IPSEC 955 /* clean ipsec history once it goes out of the node */ 956 ipsec_delaux(m); 957 #endif 958 959 #ifdef MBUF_STRESS_TEST 960 if (mbuf_frag_size && m->m_pkthdr.len > mbuf_frag_size) { 961 struct mbuf *m1, *m2; 962 int length, tmp; 963 964 tmp = length = m->m_pkthdr.len; 965 966 while ((length -= mbuf_frag_size) >= 1) { 967 m1 = m_split(m, length, MB_DONTWAIT); 968 if (m1 == NULL) 969 break; 970 m2 = m; 971 while (m2->m_next != NULL) 972 m2 = m2->m_next; 973 m2->m_next = m1; 974 } 975 m->m_pkthdr.len = tmp; 976 } 977 #endif 978 979 #ifdef MPLS 980 if (!mpls_output_process(m, ro->ro_rt)) 981 goto done; 982 #endif 983 error = ifp->if_output(ifp, m, (struct sockaddr *)dst, 984 ro->ro_rt); 985 goto done; 986 } 987 988 if (ip->ip_off & IP_DF) { 989 error = EMSGSIZE; 990 /* 991 * This case can happen if the user changed the MTU 992 * of an interface after enabling IP on it. Because 993 * most netifs don't keep track of routes pointing to 994 * them, there is no way for one to update all its 995 * routes when the MTU is changed. 996 */ 997 if ((ro->ro_rt->rt_flags & (RTF_UP | RTF_HOST)) && 998 !(ro->ro_rt->rt_rmx.rmx_locks & RTV_MTU) && 999 (ro->ro_rt->rt_rmx.rmx_mtu > ifp->if_mtu)) { 1000 ro->ro_rt->rt_rmx.rmx_mtu = ifp->if_mtu; 1001 } 1002 ipstat.ips_cantfrag++; 1003 goto bad; 1004 } 1005 1006 /* 1007 * Too large for interface; fragment if possible. If successful, 1008 * on return, m will point to a list of packets to be sent. 1009 */ 1010 error = ip_fragment(ip, &m, ifp->if_mtu, ifp->if_hwassist, sw_csum); 1011 if (error) 1012 goto bad; 1013 for (; m; m = m0) { 1014 m0 = m->m_nextpkt; 1015 m->m_nextpkt = NULL; 1016 #ifdef IPSEC 1017 /* clean ipsec history once it goes out of the node */ 1018 ipsec_delaux(m); 1019 #endif 1020 if (error == 0) { 1021 /* Record statistics for this interface address. */ 1022 if (ia != NULL) { 1023 ia->ia_ifa.if_opackets++; 1024 ia->ia_ifa.if_obytes += m->m_pkthdr.len; 1025 } 1026 #ifdef MPLS 1027 if (!mpls_output_process(m, ro->ro_rt)) 1028 continue; 1029 #endif 1030 error = ifp->if_output(ifp, m, (struct sockaddr *)dst, 1031 ro->ro_rt); 1032 } else { 1033 m_freem(m); 1034 } 1035 } 1036 1037 if (error == 0) 1038 ipstat.ips_fragmented++; 1039 1040 done: 1041 if (ro == &iproute && ro->ro_rt != NULL) { 1042 RTFREE(ro->ro_rt); 1043 ro->ro_rt = NULL; 1044 } 1045 #ifdef IPSEC 1046 if (sp != NULL) { 1047 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 1048 kprintf("DP ip_output call free SP:%p\n", sp)); 1049 key_freesp(sp); 1050 } 1051 #endif 1052 #ifdef FAST_IPSEC 1053 if (sp != NULL) 1054 KEY_FREESP(&sp); 1055 #endif 1056 return (error); 1057 bad: 1058 m_freem(m); 1059 goto done; 1060 } 1061 1062 /* 1063 * Create a chain of fragments which fit the given mtu. m_frag points to the 1064 * mbuf to be fragmented; on return it points to the chain with the fragments. 1065 * Return 0 if no error. If error, m_frag may contain a partially built 1066 * chain of fragments that should be freed by the caller. 1067 * 1068 * if_hwassist_flags is the hw offload capabilities (see if_data.ifi_hwassist) 1069 * sw_csum contains the delayed checksums flags (e.g., CSUM_DELAY_IP). 1070 */ 1071 int 1072 ip_fragment(struct ip *ip, struct mbuf **m_frag, int mtu, 1073 u_long if_hwassist_flags, int sw_csum) 1074 { 1075 int error = 0; 1076 int hlen = IP_VHL_HL(ip->ip_vhl) << 2; 1077 int len = (mtu - hlen) & ~7; /* size of payload in each fragment */ 1078 int off; 1079 struct mbuf *m0 = *m_frag; /* the original packet */ 1080 int firstlen; 1081 struct mbuf **mnext; 1082 int nfrags; 1083 1084 if (ip->ip_off & IP_DF) { /* Fragmentation not allowed */ 1085 ipstat.ips_cantfrag++; 1086 return EMSGSIZE; 1087 } 1088 1089 /* 1090 * Must be able to put at least 8 bytes per fragment. 1091 */ 1092 if (len < 8) 1093 return EMSGSIZE; 1094 1095 /* 1096 * If the interface will not calculate checksums on 1097 * fragmented packets, then do it here. 1098 */ 1099 if ((m0->m_pkthdr.csum_flags & CSUM_DELAY_DATA) && 1100 !(if_hwassist_flags & CSUM_IP_FRAGS)) { 1101 in_delayed_cksum(m0); 1102 m0->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA; 1103 } 1104 1105 if (len > PAGE_SIZE) { 1106 /* 1107 * Fragment large datagrams such that each segment 1108 * contains a multiple of PAGE_SIZE amount of data, 1109 * plus headers. This enables a receiver to perform 1110 * page-flipping zero-copy optimizations. 1111 * 1112 * XXX When does this help given that sender and receiver 1113 * could have different page sizes, and also mtu could 1114 * be less than the receiver's page size ? 1115 */ 1116 int newlen; 1117 struct mbuf *m; 1118 1119 for (m = m0, off = 0; m && (off+m->m_len) <= mtu; m = m->m_next) 1120 off += m->m_len; 1121 1122 /* 1123 * firstlen (off - hlen) must be aligned on an 1124 * 8-byte boundary 1125 */ 1126 if (off < hlen) 1127 goto smart_frag_failure; 1128 off = ((off - hlen) & ~7) + hlen; 1129 newlen = (~PAGE_MASK) & mtu; 1130 if ((newlen + sizeof(struct ip)) > mtu) { 1131 /* we failed, go back the default */ 1132 smart_frag_failure: 1133 newlen = len; 1134 off = hlen + len; 1135 } 1136 len = newlen; 1137 1138 } else { 1139 off = hlen + len; 1140 } 1141 1142 firstlen = off - hlen; 1143 mnext = &m0->m_nextpkt; /* pointer to next packet */ 1144 1145 /* 1146 * Loop through length of segment after first fragment, 1147 * make new header and copy data of each part and link onto chain. 1148 * Here, m0 is the original packet, m is the fragment being created. 1149 * The fragments are linked off the m_nextpkt of the original 1150 * packet, which after processing serves as the first fragment. 1151 */ 1152 for (nfrags = 1; off < ip->ip_len; off += len, nfrags++) { 1153 struct ip *mhip; /* ip header on the fragment */ 1154 struct mbuf *m; 1155 int mhlen = sizeof(struct ip); 1156 1157 MGETHDR(m, MB_DONTWAIT, MT_HEADER); 1158 if (m == NULL) { 1159 error = ENOBUFS; 1160 ipstat.ips_odropped++; 1161 goto done; 1162 } 1163 m->m_flags |= (m0->m_flags & M_MCAST) | M_FRAG; 1164 /* 1165 * In the first mbuf, leave room for the link header, then 1166 * copy the original IP header including options. The payload 1167 * goes into an additional mbuf chain returned by m_copy(). 1168 */ 1169 m->m_data += max_linkhdr; 1170 mhip = mtod(m, struct ip *); 1171 *mhip = *ip; 1172 if (hlen > sizeof(struct ip)) { 1173 mhlen = ip_optcopy(ip, mhip) + sizeof(struct ip); 1174 mhip->ip_vhl = IP_MAKE_VHL(IPVERSION, mhlen >> 2); 1175 } 1176 m->m_len = mhlen; 1177 /* XXX do we need to add ip->ip_off below ? */ 1178 mhip->ip_off = ((off - hlen) >> 3) + ip->ip_off; 1179 if (off + len >= ip->ip_len) { /* last fragment */ 1180 len = ip->ip_len - off; 1181 m->m_flags |= M_LASTFRAG; 1182 } else 1183 mhip->ip_off |= IP_MF; 1184 mhip->ip_len = htons((u_short)(len + mhlen)); 1185 m->m_next = m_copy(m0, off, len); 1186 if (m->m_next == NULL) { /* copy failed */ 1187 m_free(m); 1188 error = ENOBUFS; /* ??? */ 1189 ipstat.ips_odropped++; 1190 goto done; 1191 } 1192 m->m_pkthdr.len = mhlen + len; 1193 m->m_pkthdr.rcvif = NULL; 1194 m->m_pkthdr.csum_flags = m0->m_pkthdr.csum_flags; 1195 mhip->ip_off = htons(mhip->ip_off); 1196 mhip->ip_sum = 0; 1197 if (sw_csum & CSUM_DELAY_IP) 1198 mhip->ip_sum = in_cksum(m, mhlen); 1199 *mnext = m; 1200 mnext = &m->m_nextpkt; 1201 } 1202 ipstat.ips_ofragments += nfrags; 1203 1204 /* set first marker for fragment chain */ 1205 m0->m_flags |= M_FIRSTFRAG | M_FRAG; 1206 m0->m_pkthdr.csum_data = nfrags; 1207 1208 /* 1209 * Update first fragment by trimming what's been copied out 1210 * and updating header. 1211 */ 1212 m_adj(m0, hlen + firstlen - ip->ip_len); 1213 m0->m_pkthdr.len = hlen + firstlen; 1214 ip->ip_len = htons((u_short)m0->m_pkthdr.len); 1215 ip->ip_off |= IP_MF; 1216 ip->ip_off = htons(ip->ip_off); 1217 ip->ip_sum = 0; 1218 if (sw_csum & CSUM_DELAY_IP) 1219 ip->ip_sum = in_cksum(m0, hlen); 1220 1221 done: 1222 *m_frag = m0; 1223 return error; 1224 } 1225 1226 void 1227 in_delayed_cksum(struct mbuf *m) 1228 { 1229 struct ip *ip; 1230 u_short csum, offset; 1231 1232 ip = mtod(m, struct ip *); 1233 offset = IP_VHL_HL(ip->ip_vhl) << 2 ; 1234 csum = in_cksum_skip(m, ip->ip_len, offset); 1235 if (m->m_pkthdr.csum_flags & CSUM_UDP && csum == 0) 1236 csum = 0xffff; 1237 offset += m->m_pkthdr.csum_data; /* checksum offset */ 1238 1239 if (offset + sizeof(u_short) > m->m_len) { 1240 kprintf("delayed m_pullup, m->len: %d off: %d p: %d\n", 1241 m->m_len, offset, ip->ip_p); 1242 /* 1243 * XXX 1244 * this shouldn't happen, but if it does, the 1245 * correct behavior may be to insert the checksum 1246 * in the existing chain instead of rearranging it. 1247 */ 1248 m = m_pullup(m, offset + sizeof(u_short)); 1249 } 1250 *(u_short *)(m->m_data + offset) = csum; 1251 } 1252 1253 /* 1254 * Insert IP options into preformed packet. 1255 * Adjust IP destination as required for IP source routing, 1256 * as indicated by a non-zero in_addr at the start of the options. 1257 * 1258 * XXX This routine assumes that the packet has no options in place. 1259 */ 1260 static struct mbuf * 1261 ip_insertoptions(struct mbuf *m, struct mbuf *opt, int *phlen) 1262 { 1263 struct ipoption *p = mtod(opt, struct ipoption *); 1264 struct mbuf *n; 1265 struct ip *ip = mtod(m, struct ip *); 1266 unsigned optlen; 1267 1268 optlen = opt->m_len - sizeof p->ipopt_dst; 1269 if (optlen + (u_short)ip->ip_len > IP_MAXPACKET) { 1270 *phlen = 0; 1271 return (m); /* XXX should fail */ 1272 } 1273 if (p->ipopt_dst.s_addr) 1274 ip->ip_dst = p->ipopt_dst; 1275 if (m->m_flags & M_EXT || m->m_data - optlen < m->m_pktdat) { 1276 MGETHDR(n, MB_DONTWAIT, MT_HEADER); 1277 if (n == NULL) { 1278 *phlen = 0; 1279 return (m); 1280 } 1281 n->m_pkthdr.rcvif = NULL; 1282 n->m_pkthdr.len = m->m_pkthdr.len + optlen; 1283 m->m_len -= sizeof(struct ip); 1284 m->m_data += sizeof(struct ip); 1285 n->m_next = m; 1286 m = n; 1287 m->m_len = optlen + sizeof(struct ip); 1288 m->m_data += max_linkhdr; 1289 memcpy(mtod(m, void *), ip, sizeof(struct ip)); 1290 } else { 1291 m->m_data -= optlen; 1292 m->m_len += optlen; 1293 m->m_pkthdr.len += optlen; 1294 ovbcopy(ip, mtod(m, caddr_t), sizeof(struct ip)); 1295 } 1296 ip = mtod(m, struct ip *); 1297 bcopy(p->ipopt_list, ip + 1, optlen); 1298 *phlen = sizeof(struct ip) + optlen; 1299 ip->ip_vhl = IP_MAKE_VHL(IPVERSION, *phlen >> 2); 1300 ip->ip_len += optlen; 1301 return (m); 1302 } 1303 1304 /* 1305 * Copy options from ip to jp, 1306 * omitting those not copied during fragmentation. 1307 */ 1308 int 1309 ip_optcopy(struct ip *ip, struct ip *jp) 1310 { 1311 u_char *cp, *dp; 1312 int opt, optlen, cnt; 1313 1314 cp = (u_char *)(ip + 1); 1315 dp = (u_char *)(jp + 1); 1316 cnt = (IP_VHL_HL(ip->ip_vhl) << 2) - sizeof(struct ip); 1317 for (; cnt > 0; cnt -= optlen, cp += optlen) { 1318 opt = cp[0]; 1319 if (opt == IPOPT_EOL) 1320 break; 1321 if (opt == IPOPT_NOP) { 1322 /* Preserve for IP mcast tunnel's LSRR alignment. */ 1323 *dp++ = IPOPT_NOP; 1324 optlen = 1; 1325 continue; 1326 } 1327 1328 KASSERT(cnt >= IPOPT_OLEN + sizeof *cp, 1329 ("ip_optcopy: malformed ipv4 option")); 1330 optlen = cp[IPOPT_OLEN]; 1331 KASSERT(optlen >= IPOPT_OLEN + sizeof *cp && optlen <= cnt, 1332 ("ip_optcopy: malformed ipv4 option")); 1333 1334 /* bogus lengths should have been caught by ip_dooptions */ 1335 if (optlen > cnt) 1336 optlen = cnt; 1337 if (IPOPT_COPIED(opt)) { 1338 bcopy(cp, dp, optlen); 1339 dp += optlen; 1340 } 1341 } 1342 for (optlen = dp - (u_char *)(jp+1); optlen & 0x3; optlen++) 1343 *dp++ = IPOPT_EOL; 1344 return (optlen); 1345 } 1346 1347 /* 1348 * IP socket option processing. 1349 */ 1350 void 1351 ip_ctloutput(netmsg_t msg) 1352 { 1353 struct socket *so = msg->base.nm_so; 1354 struct sockopt *sopt = msg->ctloutput.nm_sopt; 1355 struct inpcb *inp = so->so_pcb; 1356 int error, optval; 1357 1358 error = optval = 0; 1359 if (sopt->sopt_level != IPPROTO_IP) { 1360 error = EINVAL; 1361 goto done; 1362 } 1363 1364 switch (sopt->sopt_dir) { 1365 case SOPT_SET: 1366 switch (sopt->sopt_name) { 1367 case IP_OPTIONS: 1368 #ifdef notyet 1369 case IP_RETOPTS: 1370 #endif 1371 { 1372 struct mbuf *m; 1373 if (sopt->sopt_valsize > MLEN) { 1374 error = EMSGSIZE; 1375 break; 1376 } 1377 MGET(m, sopt->sopt_td ? MB_WAIT : MB_DONTWAIT, MT_HEADER); 1378 if (m == NULL) { 1379 error = ENOBUFS; 1380 break; 1381 } 1382 m->m_len = sopt->sopt_valsize; 1383 error = soopt_to_kbuf(sopt, mtod(m, void *), m->m_len, 1384 m->m_len); 1385 error = ip_pcbopts(sopt->sopt_name, 1386 &inp->inp_options, m); 1387 goto done; 1388 } 1389 1390 case IP_TOS: 1391 case IP_TTL: 1392 case IP_MINTTL: 1393 case IP_RECVOPTS: 1394 case IP_RECVRETOPTS: 1395 case IP_RECVDSTADDR: 1396 case IP_RECVIF: 1397 case IP_RECVTTL: 1398 case IP_FAITH: 1399 error = soopt_to_kbuf(sopt, &optval, sizeof optval, 1400 sizeof optval); 1401 if (error) 1402 break; 1403 switch (sopt->sopt_name) { 1404 case IP_TOS: 1405 inp->inp_ip_tos = optval; 1406 break; 1407 1408 case IP_TTL: 1409 inp->inp_ip_ttl = optval; 1410 break; 1411 case IP_MINTTL: 1412 if (optval >= 0 && optval <= MAXTTL) 1413 inp->inp_ip_minttl = optval; 1414 else 1415 error = EINVAL; 1416 break; 1417 #define OPTSET(bit) \ 1418 if (optval) \ 1419 inp->inp_flags |= bit; \ 1420 else \ 1421 inp->inp_flags &= ~bit; 1422 1423 case IP_RECVOPTS: 1424 OPTSET(INP_RECVOPTS); 1425 break; 1426 1427 case IP_RECVRETOPTS: 1428 OPTSET(INP_RECVRETOPTS); 1429 break; 1430 1431 case IP_RECVDSTADDR: 1432 OPTSET(INP_RECVDSTADDR); 1433 break; 1434 1435 case IP_RECVIF: 1436 OPTSET(INP_RECVIF); 1437 break; 1438 1439 case IP_RECVTTL: 1440 OPTSET(INP_RECVTTL); 1441 break; 1442 1443 case IP_FAITH: 1444 OPTSET(INP_FAITH); 1445 break; 1446 } 1447 break; 1448 #undef OPTSET 1449 1450 case IP_MULTICAST_IF: 1451 case IP_MULTICAST_VIF: 1452 case IP_MULTICAST_TTL: 1453 case IP_MULTICAST_LOOP: 1454 case IP_ADD_MEMBERSHIP: 1455 case IP_DROP_MEMBERSHIP: 1456 error = ip_setmoptions(sopt, &inp->inp_moptions); 1457 break; 1458 1459 case IP_PORTRANGE: 1460 error = soopt_to_kbuf(sopt, &optval, sizeof optval, 1461 sizeof optval); 1462 if (error) 1463 break; 1464 1465 switch (optval) { 1466 case IP_PORTRANGE_DEFAULT: 1467 inp->inp_flags &= ~(INP_LOWPORT); 1468 inp->inp_flags &= ~(INP_HIGHPORT); 1469 break; 1470 1471 case IP_PORTRANGE_HIGH: 1472 inp->inp_flags &= ~(INP_LOWPORT); 1473 inp->inp_flags |= INP_HIGHPORT; 1474 break; 1475 1476 case IP_PORTRANGE_LOW: 1477 inp->inp_flags &= ~(INP_HIGHPORT); 1478 inp->inp_flags |= INP_LOWPORT; 1479 break; 1480 1481 default: 1482 error = EINVAL; 1483 break; 1484 } 1485 break; 1486 1487 #if defined(IPSEC) || defined(FAST_IPSEC) 1488 case IP_IPSEC_POLICY: 1489 { 1490 caddr_t req; 1491 size_t len = 0; 1492 int priv; 1493 struct mbuf *m; 1494 int optname; 1495 1496 if ((error = soopt_getm(sopt, &m)) != 0) /* XXX */ 1497 break; 1498 soopt_to_mbuf(sopt, m); 1499 priv = (sopt->sopt_td != NULL && 1500 priv_check(sopt->sopt_td, PRIV_ROOT) != 0) ? 0 : 1; 1501 req = mtod(m, caddr_t); 1502 len = m->m_len; 1503 optname = sopt->sopt_name; 1504 error = ipsec4_set_policy(inp, optname, req, len, priv); 1505 m_freem(m); 1506 break; 1507 } 1508 #endif /*IPSEC*/ 1509 1510 default: 1511 error = ENOPROTOOPT; 1512 break; 1513 } 1514 break; 1515 1516 case SOPT_GET: 1517 switch (sopt->sopt_name) { 1518 case IP_OPTIONS: 1519 case IP_RETOPTS: 1520 if (inp->inp_options) 1521 soopt_from_kbuf(sopt, mtod(inp->inp_options, 1522 char *), 1523 inp->inp_options->m_len); 1524 else 1525 sopt->sopt_valsize = 0; 1526 break; 1527 1528 case IP_TOS: 1529 case IP_TTL: 1530 case IP_MINTTL: 1531 case IP_RECVOPTS: 1532 case IP_RECVRETOPTS: 1533 case IP_RECVDSTADDR: 1534 case IP_RECVTTL: 1535 case IP_RECVIF: 1536 case IP_PORTRANGE: 1537 case IP_FAITH: 1538 switch (sopt->sopt_name) { 1539 1540 case IP_TOS: 1541 optval = inp->inp_ip_tos; 1542 break; 1543 1544 case IP_TTL: 1545 optval = inp->inp_ip_ttl; 1546 break; 1547 case IP_MINTTL: 1548 optval = inp->inp_ip_minttl; 1549 break; 1550 1551 #define OPTBIT(bit) (inp->inp_flags & bit ? 1 : 0) 1552 1553 case IP_RECVOPTS: 1554 optval = OPTBIT(INP_RECVOPTS); 1555 break; 1556 1557 case IP_RECVRETOPTS: 1558 optval = OPTBIT(INP_RECVRETOPTS); 1559 break; 1560 1561 case IP_RECVDSTADDR: 1562 optval = OPTBIT(INP_RECVDSTADDR); 1563 break; 1564 1565 case IP_RECVTTL: 1566 optval = OPTBIT(INP_RECVTTL); 1567 break; 1568 1569 case IP_RECVIF: 1570 optval = OPTBIT(INP_RECVIF); 1571 break; 1572 1573 case IP_PORTRANGE: 1574 if (inp->inp_flags & INP_HIGHPORT) 1575 optval = IP_PORTRANGE_HIGH; 1576 else if (inp->inp_flags & INP_LOWPORT) 1577 optval = IP_PORTRANGE_LOW; 1578 else 1579 optval = 0; 1580 break; 1581 1582 case IP_FAITH: 1583 optval = OPTBIT(INP_FAITH); 1584 break; 1585 } 1586 soopt_from_kbuf(sopt, &optval, sizeof optval); 1587 break; 1588 1589 case IP_MULTICAST_IF: 1590 case IP_MULTICAST_VIF: 1591 case IP_MULTICAST_TTL: 1592 case IP_MULTICAST_LOOP: 1593 case IP_ADD_MEMBERSHIP: 1594 case IP_DROP_MEMBERSHIP: 1595 error = ip_getmoptions(sopt, inp->inp_moptions); 1596 break; 1597 1598 #if defined(IPSEC) || defined(FAST_IPSEC) 1599 case IP_IPSEC_POLICY: 1600 { 1601 struct mbuf *m = NULL; 1602 caddr_t req = NULL; 1603 size_t len = 0; 1604 1605 if (m != NULL) { 1606 req = mtod(m, caddr_t); 1607 len = m->m_len; 1608 } 1609 error = ipsec4_get_policy(so->so_pcb, req, len, &m); 1610 if (error == 0) 1611 error = soopt_from_mbuf(sopt, m); /* XXX */ 1612 if (error == 0) 1613 m_freem(m); 1614 break; 1615 } 1616 #endif /*IPSEC*/ 1617 1618 default: 1619 error = ENOPROTOOPT; 1620 break; 1621 } 1622 break; 1623 } 1624 done: 1625 lwkt_replymsg(&msg->lmsg, error); 1626 } 1627 1628 /* 1629 * Set up IP options in pcb for insertion in output packets. 1630 * Store in mbuf with pointer in pcbopt, adding pseudo-option 1631 * with destination address if source routed. 1632 */ 1633 static int 1634 ip_pcbopts(int optname, struct mbuf **pcbopt, struct mbuf *m) 1635 { 1636 int cnt, optlen; 1637 u_char *cp; 1638 u_char opt; 1639 1640 /* turn off any old options */ 1641 if (*pcbopt) 1642 m_free(*pcbopt); 1643 *pcbopt = 0; 1644 if (m == NULL || m->m_len == 0) { 1645 /* 1646 * Only turning off any previous options. 1647 */ 1648 if (m != NULL) 1649 m_free(m); 1650 return (0); 1651 } 1652 1653 if (m->m_len % sizeof(int32_t)) 1654 goto bad; 1655 /* 1656 * IP first-hop destination address will be stored before 1657 * actual options; move other options back 1658 * and clear it when none present. 1659 */ 1660 if (m->m_data + m->m_len + sizeof(struct in_addr) >= &m->m_dat[MLEN]) 1661 goto bad; 1662 cnt = m->m_len; 1663 m->m_len += sizeof(struct in_addr); 1664 cp = mtod(m, u_char *) + sizeof(struct in_addr); 1665 ovbcopy(mtod(m, caddr_t), cp, cnt); 1666 bzero(mtod(m, caddr_t), sizeof(struct in_addr)); 1667 1668 for (; cnt > 0; cnt -= optlen, cp += optlen) { 1669 opt = cp[IPOPT_OPTVAL]; 1670 if (opt == IPOPT_EOL) 1671 break; 1672 if (opt == IPOPT_NOP) 1673 optlen = 1; 1674 else { 1675 if (cnt < IPOPT_OLEN + sizeof *cp) 1676 goto bad; 1677 optlen = cp[IPOPT_OLEN]; 1678 if (optlen < IPOPT_OLEN + sizeof *cp || optlen > cnt) 1679 goto bad; 1680 } 1681 switch (opt) { 1682 1683 default: 1684 break; 1685 1686 case IPOPT_LSRR: 1687 case IPOPT_SSRR: 1688 /* 1689 * user process specifies route as: 1690 * ->A->B->C->D 1691 * D must be our final destination (but we can't 1692 * check that since we may not have connected yet). 1693 * A is first hop destination, which doesn't appear in 1694 * actual IP option, but is stored before the options. 1695 */ 1696 if (optlen < IPOPT_MINOFF - 1 + sizeof(struct in_addr)) 1697 goto bad; 1698 m->m_len -= sizeof(struct in_addr); 1699 cnt -= sizeof(struct in_addr); 1700 optlen -= sizeof(struct in_addr); 1701 cp[IPOPT_OLEN] = optlen; 1702 /* 1703 * Move first hop before start of options. 1704 */ 1705 bcopy(&cp[IPOPT_OFFSET+1], mtod(m, caddr_t), 1706 sizeof(struct in_addr)); 1707 /* 1708 * Then copy rest of options back 1709 * to close up the deleted entry. 1710 */ 1711 ovbcopy(&cp[IPOPT_OFFSET+1] + sizeof(struct in_addr), 1712 &cp[IPOPT_OFFSET+1], 1713 cnt - (IPOPT_MINOFF - 1)); 1714 break; 1715 } 1716 } 1717 if (m->m_len > MAX_IPOPTLEN + sizeof(struct in_addr)) 1718 goto bad; 1719 *pcbopt = m; 1720 return (0); 1721 1722 bad: 1723 m_free(m); 1724 return (EINVAL); 1725 } 1726 1727 /* 1728 * XXX 1729 * The whole multicast option thing needs to be re-thought. 1730 * Several of these options are equally applicable to non-multicast 1731 * transmission, and one (IP_MULTICAST_TTL) totally duplicates a 1732 * standard option (IP_TTL). 1733 */ 1734 1735 /* 1736 * following RFC1724 section 3.3, 0.0.0.0/8 is interpreted as interface index. 1737 */ 1738 static struct ifnet * 1739 ip_multicast_if(struct in_addr *a, int *ifindexp) 1740 { 1741 int ifindex; 1742 struct ifnet *ifp; 1743 1744 if (ifindexp) 1745 *ifindexp = 0; 1746 if (ntohl(a->s_addr) >> 24 == 0) { 1747 ifindex = ntohl(a->s_addr) & 0xffffff; 1748 if (ifindex < 0 || if_index < ifindex) 1749 return NULL; 1750 ifp = ifindex2ifnet[ifindex]; 1751 if (ifindexp) 1752 *ifindexp = ifindex; 1753 } else { 1754 ifp = INADDR_TO_IFP(a); 1755 } 1756 return ifp; 1757 } 1758 1759 /* 1760 * Set the IP multicast options in response to user setsockopt(). 1761 */ 1762 static int 1763 ip_setmoptions(struct sockopt *sopt, struct ip_moptions **imop) 1764 { 1765 int error = 0; 1766 int i; 1767 struct in_addr addr; 1768 struct ip_mreq mreq; 1769 struct ifnet *ifp; 1770 struct ip_moptions *imo = *imop; 1771 int ifindex; 1772 1773 if (imo == NULL) { 1774 /* 1775 * No multicast option buffer attached to the pcb; 1776 * allocate one and initialize to default values. 1777 */ 1778 imo = kmalloc(sizeof *imo, M_IPMOPTS, M_WAITOK); 1779 1780 *imop = imo; 1781 imo->imo_multicast_ifp = NULL; 1782 imo->imo_multicast_addr.s_addr = INADDR_ANY; 1783 imo->imo_multicast_vif = -1; 1784 imo->imo_multicast_ttl = IP_DEFAULT_MULTICAST_TTL; 1785 imo->imo_multicast_loop = IP_DEFAULT_MULTICAST_LOOP; 1786 imo->imo_num_memberships = 0; 1787 } 1788 switch (sopt->sopt_name) { 1789 /* store an index number for the vif you wanna use in the send */ 1790 case IP_MULTICAST_VIF: 1791 if (legal_vif_num == 0) { 1792 error = EOPNOTSUPP; 1793 break; 1794 } 1795 error = soopt_to_kbuf(sopt, &i, sizeof i, sizeof i); 1796 if (error) 1797 break; 1798 if (!legal_vif_num(i) && (i != -1)) { 1799 error = EINVAL; 1800 break; 1801 } 1802 imo->imo_multicast_vif = i; 1803 break; 1804 1805 case IP_MULTICAST_IF: 1806 /* 1807 * Select the interface for outgoing multicast packets. 1808 */ 1809 error = soopt_to_kbuf(sopt, &addr, sizeof addr, sizeof addr); 1810 if (error) 1811 break; 1812 1813 /* 1814 * INADDR_ANY is used to remove a previous selection. 1815 * When no interface is selected, a default one is 1816 * chosen every time a multicast packet is sent. 1817 */ 1818 if (addr.s_addr == INADDR_ANY) { 1819 imo->imo_multicast_ifp = NULL; 1820 break; 1821 } 1822 /* 1823 * The selected interface is identified by its local 1824 * IP address. Find the interface and confirm that 1825 * it supports multicasting. 1826 */ 1827 crit_enter(); 1828 ifp = ip_multicast_if(&addr, &ifindex); 1829 if (ifp == NULL || !(ifp->if_flags & IFF_MULTICAST)) { 1830 crit_exit(); 1831 error = EADDRNOTAVAIL; 1832 break; 1833 } 1834 imo->imo_multicast_ifp = ifp; 1835 if (ifindex) 1836 imo->imo_multicast_addr = addr; 1837 else 1838 imo->imo_multicast_addr.s_addr = INADDR_ANY; 1839 crit_exit(); 1840 break; 1841 1842 case IP_MULTICAST_TTL: 1843 /* 1844 * Set the IP time-to-live for outgoing multicast packets. 1845 * The original multicast API required a char argument, 1846 * which is inconsistent with the rest of the socket API. 1847 * We allow either a char or an int. 1848 */ 1849 if (sopt->sopt_valsize == 1) { 1850 u_char ttl; 1851 error = soopt_to_kbuf(sopt, &ttl, 1, 1); 1852 if (error) 1853 break; 1854 imo->imo_multicast_ttl = ttl; 1855 } else { 1856 u_int ttl; 1857 error = soopt_to_kbuf(sopt, &ttl, sizeof ttl, sizeof ttl); 1858 if (error) 1859 break; 1860 if (ttl > 255) 1861 error = EINVAL; 1862 else 1863 imo->imo_multicast_ttl = ttl; 1864 } 1865 break; 1866 1867 case IP_MULTICAST_LOOP: 1868 /* 1869 * Set the loopback flag for outgoing multicast packets. 1870 * Must be zero or one. The original multicast API required a 1871 * char argument, which is inconsistent with the rest 1872 * of the socket API. We allow either a char or an int. 1873 */ 1874 if (sopt->sopt_valsize == 1) { 1875 u_char loop; 1876 1877 error = soopt_to_kbuf(sopt, &loop, 1, 1); 1878 if (error) 1879 break; 1880 imo->imo_multicast_loop = !!loop; 1881 } else { 1882 u_int loop; 1883 1884 error = soopt_to_kbuf(sopt, &loop, sizeof loop, 1885 sizeof loop); 1886 if (error) 1887 break; 1888 imo->imo_multicast_loop = !!loop; 1889 } 1890 break; 1891 1892 case IP_ADD_MEMBERSHIP: 1893 /* 1894 * Add a multicast group membership. 1895 * Group must be a valid IP multicast address. 1896 */ 1897 error = soopt_to_kbuf(sopt, &mreq, sizeof mreq, sizeof mreq); 1898 if (error) 1899 break; 1900 1901 if (!IN_MULTICAST(ntohl(mreq.imr_multiaddr.s_addr))) { 1902 error = EINVAL; 1903 break; 1904 } 1905 crit_enter(); 1906 /* 1907 * If no interface address was provided, use the interface of 1908 * the route to the given multicast address. 1909 */ 1910 if (mreq.imr_interface.s_addr == INADDR_ANY) { 1911 struct sockaddr_in dst; 1912 struct rtentry *rt; 1913 1914 bzero(&dst, sizeof(struct sockaddr_in)); 1915 dst.sin_len = sizeof(struct sockaddr_in); 1916 dst.sin_family = AF_INET; 1917 dst.sin_addr = mreq.imr_multiaddr; 1918 rt = rtlookup((struct sockaddr *)&dst); 1919 if (rt == NULL) { 1920 error = EADDRNOTAVAIL; 1921 crit_exit(); 1922 break; 1923 } 1924 --rt->rt_refcnt; 1925 ifp = rt->rt_ifp; 1926 } else { 1927 ifp = ip_multicast_if(&mreq.imr_interface, NULL); 1928 } 1929 1930 /* 1931 * See if we found an interface, and confirm that it 1932 * supports multicast. 1933 */ 1934 if (ifp == NULL || !(ifp->if_flags & IFF_MULTICAST)) { 1935 error = EADDRNOTAVAIL; 1936 crit_exit(); 1937 break; 1938 } 1939 /* 1940 * See if the membership already exists or if all the 1941 * membership slots are full. 1942 */ 1943 for (i = 0; i < imo->imo_num_memberships; ++i) { 1944 if (imo->imo_membership[i]->inm_ifp == ifp && 1945 imo->imo_membership[i]->inm_addr.s_addr 1946 == mreq.imr_multiaddr.s_addr) 1947 break; 1948 } 1949 if (i < imo->imo_num_memberships) { 1950 error = EADDRINUSE; 1951 crit_exit(); 1952 break; 1953 } 1954 if (i == IP_MAX_MEMBERSHIPS) { 1955 error = ETOOMANYREFS; 1956 crit_exit(); 1957 break; 1958 } 1959 /* 1960 * Everything looks good; add a new record to the multicast 1961 * address list for the given interface. 1962 */ 1963 if ((imo->imo_membership[i] = 1964 in_addmulti(&mreq.imr_multiaddr, ifp)) == NULL) { 1965 error = ENOBUFS; 1966 crit_exit(); 1967 break; 1968 } 1969 ++imo->imo_num_memberships; 1970 crit_exit(); 1971 break; 1972 1973 case IP_DROP_MEMBERSHIP: 1974 /* 1975 * Drop a multicast group membership. 1976 * Group must be a valid IP multicast address. 1977 */ 1978 error = soopt_to_kbuf(sopt, &mreq, sizeof mreq, sizeof mreq); 1979 if (error) 1980 break; 1981 1982 if (!IN_MULTICAST(ntohl(mreq.imr_multiaddr.s_addr))) { 1983 error = EINVAL; 1984 break; 1985 } 1986 1987 crit_enter(); 1988 /* 1989 * If an interface address was specified, get a pointer 1990 * to its ifnet structure. 1991 */ 1992 if (mreq.imr_interface.s_addr == INADDR_ANY) 1993 ifp = NULL; 1994 else { 1995 ifp = ip_multicast_if(&mreq.imr_interface, NULL); 1996 if (ifp == NULL) { 1997 error = EADDRNOTAVAIL; 1998 crit_exit(); 1999 break; 2000 } 2001 } 2002 /* 2003 * Find the membership in the membership array. 2004 */ 2005 for (i = 0; i < imo->imo_num_memberships; ++i) { 2006 if ((ifp == NULL || 2007 imo->imo_membership[i]->inm_ifp == ifp) && 2008 imo->imo_membership[i]->inm_addr.s_addr == 2009 mreq.imr_multiaddr.s_addr) 2010 break; 2011 } 2012 if (i == imo->imo_num_memberships) { 2013 error = EADDRNOTAVAIL; 2014 crit_exit(); 2015 break; 2016 } 2017 /* 2018 * Give up the multicast address record to which the 2019 * membership points. 2020 */ 2021 in_delmulti(imo->imo_membership[i]); 2022 /* 2023 * Remove the gap in the membership array. 2024 */ 2025 for (++i; i < imo->imo_num_memberships; ++i) 2026 imo->imo_membership[i-1] = imo->imo_membership[i]; 2027 --imo->imo_num_memberships; 2028 crit_exit(); 2029 break; 2030 2031 default: 2032 error = EOPNOTSUPP; 2033 break; 2034 } 2035 2036 /* 2037 * If all options have default values, no need to keep the mbuf. 2038 */ 2039 if (imo->imo_multicast_ifp == NULL && 2040 imo->imo_multicast_vif == -1 && 2041 imo->imo_multicast_ttl == IP_DEFAULT_MULTICAST_TTL && 2042 imo->imo_multicast_loop == IP_DEFAULT_MULTICAST_LOOP && 2043 imo->imo_num_memberships == 0) { 2044 kfree(*imop, M_IPMOPTS); 2045 *imop = NULL; 2046 } 2047 2048 return (error); 2049 } 2050 2051 /* 2052 * Return the IP multicast options in response to user getsockopt(). 2053 */ 2054 static int 2055 ip_getmoptions(struct sockopt *sopt, struct ip_moptions *imo) 2056 { 2057 struct in_addr addr; 2058 struct in_ifaddr *ia; 2059 int error, optval; 2060 u_char coptval; 2061 2062 error = 0; 2063 switch (sopt->sopt_name) { 2064 case IP_MULTICAST_VIF: 2065 if (imo != NULL) 2066 optval = imo->imo_multicast_vif; 2067 else 2068 optval = -1; 2069 soopt_from_kbuf(sopt, &optval, sizeof optval); 2070 break; 2071 2072 case IP_MULTICAST_IF: 2073 if (imo == NULL || imo->imo_multicast_ifp == NULL) 2074 addr.s_addr = INADDR_ANY; 2075 else if (imo->imo_multicast_addr.s_addr) { 2076 /* return the value user has set */ 2077 addr = imo->imo_multicast_addr; 2078 } else { 2079 ia = IFP_TO_IA(imo->imo_multicast_ifp); 2080 addr.s_addr = (ia == NULL) ? INADDR_ANY 2081 : IA_SIN(ia)->sin_addr.s_addr; 2082 } 2083 soopt_from_kbuf(sopt, &addr, sizeof addr); 2084 break; 2085 2086 case IP_MULTICAST_TTL: 2087 if (imo == NULL) 2088 optval = coptval = IP_DEFAULT_MULTICAST_TTL; 2089 else 2090 optval = coptval = imo->imo_multicast_ttl; 2091 if (sopt->sopt_valsize == 1) 2092 soopt_from_kbuf(sopt, &coptval, 1); 2093 else 2094 soopt_from_kbuf(sopt, &optval, sizeof optval); 2095 break; 2096 2097 case IP_MULTICAST_LOOP: 2098 if (imo == NULL) 2099 optval = coptval = IP_DEFAULT_MULTICAST_LOOP; 2100 else 2101 optval = coptval = imo->imo_multicast_loop; 2102 if (sopt->sopt_valsize == 1) 2103 soopt_from_kbuf(sopt, &coptval, 1); 2104 else 2105 soopt_from_kbuf(sopt, &optval, sizeof optval); 2106 break; 2107 2108 default: 2109 error = ENOPROTOOPT; 2110 break; 2111 } 2112 return (error); 2113 } 2114 2115 /* 2116 * Discard the IP multicast options. 2117 */ 2118 void 2119 ip_freemoptions(struct ip_moptions *imo) 2120 { 2121 int i; 2122 2123 if (imo != NULL) { 2124 for (i = 0; i < imo->imo_num_memberships; ++i) 2125 in_delmulti(imo->imo_membership[i]); 2126 kfree(imo, M_IPMOPTS); 2127 } 2128 } 2129 2130 /* 2131 * Routine called from ip_output() to loop back a copy of an IP multicast 2132 * packet to the input queue of a specified interface. Note that this 2133 * calls the output routine of the loopback "driver", but with an interface 2134 * pointer that might NOT be a loopback interface -- evil, but easier than 2135 * replicating that code here. 2136 */ 2137 static void 2138 ip_mloopback(struct ifnet *ifp, struct mbuf *m, struct sockaddr_in *dst, 2139 int hlen) 2140 { 2141 struct ip *ip; 2142 struct mbuf *copym; 2143 2144 copym = m_copypacket(m, MB_DONTWAIT); 2145 if (copym != NULL && (copym->m_flags & M_EXT || copym->m_len < hlen)) 2146 copym = m_pullup(copym, hlen); 2147 if (copym != NULL) { 2148 /* 2149 * if the checksum hasn't been computed, mark it as valid 2150 */ 2151 if (copym->m_pkthdr.csum_flags & CSUM_DELAY_DATA) { 2152 in_delayed_cksum(copym); 2153 copym->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA; 2154 copym->m_pkthdr.csum_flags |= 2155 CSUM_DATA_VALID | CSUM_PSEUDO_HDR; 2156 copym->m_pkthdr.csum_data = 0xffff; 2157 } 2158 /* 2159 * We don't bother to fragment if the IP length is greater 2160 * than the interface's MTU. Can this possibly matter? 2161 */ 2162 ip = mtod(copym, struct ip *); 2163 ip->ip_len = htons(ip->ip_len); 2164 ip->ip_off = htons(ip->ip_off); 2165 ip->ip_sum = 0; 2166 if (ip->ip_vhl == IP_VHL_BORING) { 2167 ip->ip_sum = in_cksum_hdr(ip); 2168 } else { 2169 ip->ip_sum = in_cksum(copym, hlen); 2170 } 2171 /* 2172 * NB: 2173 * It's not clear whether there are any lingering 2174 * reentrancy problems in other areas which might 2175 * be exposed by using ip_input directly (in 2176 * particular, everything which modifies the packet 2177 * in-place). Yet another option is using the 2178 * protosw directly to deliver the looped back 2179 * packet. For the moment, we'll err on the side 2180 * of safety by using if_simloop(). 2181 */ 2182 #if 1 /* XXX */ 2183 if (dst->sin_family != AF_INET) { 2184 kprintf("ip_mloopback: bad address family %d\n", 2185 dst->sin_family); 2186 dst->sin_family = AF_INET; 2187 } 2188 #endif 2189 if_simloop(ifp, copym, dst->sin_family, 0); 2190 } 2191 } 2192