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 dst = (struct sockaddr_in *)&ro->ro_dst; 310 /* 311 * If there is a cached route, 312 * check that it is to the same destination 313 * and is still up. If not, free it and try again. 314 * The address family should also be checked in case of sharing the 315 * cache with IPv6. 316 */ 317 if (ro->ro_rt && 318 (!(ro->ro_rt->rt_flags & RTF_UP) || 319 dst->sin_family != AF_INET || 320 dst->sin_addr.s_addr != pkt_dst.s_addr)) { 321 rtfree(ro->ro_rt); 322 ro->ro_rt = NULL; 323 } 324 if (ro->ro_rt == NULL) { 325 bzero(dst, sizeof *dst); 326 dst->sin_family = AF_INET; 327 dst->sin_len = sizeof *dst; 328 dst->sin_addr = pkt_dst; 329 } 330 /* 331 * If routing to interface only, 332 * short circuit routing lookup. 333 */ 334 if (flags & IP_ROUTETOIF) { 335 if ((ia = ifatoia(ifa_ifwithdstaddr(sintosa(dst)))) == NULL && 336 (ia = ifatoia(ifa_ifwithnet(sintosa(dst)))) == NULL) { 337 ipstat.ips_noroute++; 338 error = ENETUNREACH; 339 goto bad; 340 } 341 ifp = ia->ia_ifp; 342 ip->ip_ttl = 1; 343 isbroadcast = in_broadcast(dst->sin_addr, ifp); 344 } else if (IN_MULTICAST(ntohl(pkt_dst.s_addr)) && 345 imo != NULL && imo->imo_multicast_ifp != NULL) { 346 /* 347 * Bypass the normal routing lookup for multicast 348 * packets if the interface is specified. 349 */ 350 ifp = imo->imo_multicast_ifp; 351 ia = IFP_TO_IA(ifp); 352 isbroadcast = 0; /* fool gcc */ 353 } else { 354 /* 355 * If this is the case, we probably don't want to allocate 356 * a protocol-cloned route since we didn't get one from the 357 * ULP. This lets TCP do its thing, while not burdening 358 * forwarding or ICMP with the overhead of cloning a route. 359 * Of course, we still want to do any cloning requested by 360 * the link layer, as this is probably required in all cases 361 * for correct operation (as it is for ARP). 362 */ 363 if (ro->ro_rt == NULL) 364 rtalloc_ign(ro, RTF_PRCLONING); 365 if (ro->ro_rt == NULL) { 366 ipstat.ips_noroute++; 367 error = EHOSTUNREACH; 368 goto bad; 369 } 370 ia = ifatoia(ro->ro_rt->rt_ifa); 371 ifp = ro->ro_rt->rt_ifp; 372 ro->ro_rt->rt_use++; 373 if (ro->ro_rt->rt_flags & RTF_GATEWAY) 374 dst = (struct sockaddr_in *)ro->ro_rt->rt_gateway; 375 if (ro->ro_rt->rt_flags & RTF_HOST) 376 isbroadcast = (ro->ro_rt->rt_flags & RTF_BROADCAST); 377 else 378 isbroadcast = in_broadcast(dst->sin_addr, ifp); 379 } 380 if (IN_MULTICAST(ntohl(pkt_dst.s_addr))) { 381 struct in_multi *inm; 382 383 m->m_flags |= M_MCAST; 384 /* 385 * IP destination address is multicast. Make sure "dst" 386 * still points to the address in "ro". (It may have been 387 * changed to point to a gateway address, above.) 388 */ 389 dst = (struct sockaddr_in *)&ro->ro_dst; 390 /* 391 * See if the caller provided any multicast options 392 */ 393 if (imo != NULL) { 394 ip->ip_ttl = imo->imo_multicast_ttl; 395 if (imo->imo_multicast_vif != -1) { 396 ip->ip_src.s_addr = 397 ip_mcast_src ? 398 ip_mcast_src(imo->imo_multicast_vif) : 399 INADDR_ANY; 400 } 401 } else { 402 ip->ip_ttl = IP_DEFAULT_MULTICAST_TTL; 403 } 404 /* 405 * Confirm that the outgoing interface supports multicast. 406 */ 407 if ((imo == NULL) || (imo->imo_multicast_vif == -1)) { 408 if (!(ifp->if_flags & IFF_MULTICAST)) { 409 ipstat.ips_noroute++; 410 error = ENETUNREACH; 411 goto bad; 412 } 413 } 414 /* 415 * If source address not specified yet, use address 416 * of outgoing interface. 417 */ 418 if (ip->ip_src.s_addr == INADDR_ANY) { 419 /* Interface may have no addresses. */ 420 if (ia != NULL) 421 ip->ip_src = IA_SIN(ia)->sin_addr; 422 } 423 424 IN_LOOKUP_MULTI(pkt_dst, ifp, inm); 425 if (inm != NULL && 426 (imo == NULL || imo->imo_multicast_loop)) { 427 /* 428 * If we belong to the destination multicast group 429 * on the outgoing interface, and the caller did not 430 * forbid loopback, loop back a copy. 431 */ 432 ip_mloopback(ifp, m, dst, hlen); 433 } else { 434 /* 435 * If we are acting as a multicast router, perform 436 * multicast forwarding as if the packet had just 437 * arrived on the interface to which we are about 438 * to send. The multicast forwarding function 439 * recursively calls this function, using the 440 * IP_FORWARDING flag to prevent infinite recursion. 441 * 442 * Multicasts that are looped back by ip_mloopback(), 443 * above, will be forwarded by the ip_input() routine, 444 * if necessary. 445 */ 446 if (ip_mrouter && !(flags & IP_FORWARDING)) { 447 /* 448 * If rsvp daemon is not running, do not 449 * set ip_moptions. This ensures that the packet 450 * is multicast and not just sent down one link 451 * as prescribed by rsvpd. 452 */ 453 if (!rsvp_on) 454 imo = NULL; 455 if (ip_mforward) { 456 get_mplock(); 457 if (ip_mforward(ip, ifp, m, imo) != 0) { 458 m_freem(m); 459 rel_mplock(); 460 goto done; 461 } 462 rel_mplock(); 463 } 464 } 465 } 466 467 /* 468 * Multicasts with a time-to-live of zero may be looped- 469 * back, above, but must not be transmitted on a network. 470 * Also, multicasts addressed to the loopback interface 471 * are not sent -- the above call to ip_mloopback() will 472 * loop back a copy if this host actually belongs to the 473 * destination group on the loopback interface. 474 */ 475 if (ip->ip_ttl == 0 || ifp->if_flags & IFF_LOOPBACK) { 476 m_freem(m); 477 goto done; 478 } 479 480 goto sendit; 481 } else { 482 m->m_flags &= ~M_MCAST; 483 } 484 485 /* 486 * If the source address is not specified yet, use the address 487 * of the outoing interface. In case, keep note we did that, so 488 * if the the firewall changes the next-hop causing the output 489 * interface to change, we can fix that. 490 */ 491 if (ip->ip_src.s_addr == INADDR_ANY || src_was_INADDR_ANY) { 492 /* Interface may have no addresses. */ 493 if (ia != NULL) { 494 ip->ip_src = IA_SIN(ia)->sin_addr; 495 src_was_INADDR_ANY = 1; 496 } 497 } 498 499 #ifdef ALTQ 500 /* 501 * Disable packet drop hack. 502 * Packetdrop should be done by queueing. 503 */ 504 #else /* !ALTQ */ 505 /* 506 * Verify that we have any chance at all of being able to queue 507 * the packet or packet fragments 508 */ 509 if ((ifp->if_snd.ifq_len + ip->ip_len / ifp->if_mtu + 1) >= 510 ifp->if_snd.ifq_maxlen) { 511 error = ENOBUFS; 512 ipstat.ips_odropped++; 513 goto bad; 514 } 515 #endif /* !ALTQ */ 516 517 /* 518 * Look for broadcast address and 519 * verify user is allowed to send 520 * such a packet. 521 */ 522 if (isbroadcast) { 523 if (!(ifp->if_flags & IFF_BROADCAST)) { 524 error = EADDRNOTAVAIL; 525 goto bad; 526 } 527 if (!(flags & IP_ALLOWBROADCAST)) { 528 error = EACCES; 529 goto bad; 530 } 531 /* don't allow broadcast messages to be fragmented */ 532 if (ip->ip_len > ifp->if_mtu) { 533 error = EMSGSIZE; 534 goto bad; 535 } 536 m->m_flags |= M_BCAST; 537 } else { 538 m->m_flags &= ~M_BCAST; 539 } 540 541 sendit: 542 #ifdef IPSEC 543 /* get SP for this packet */ 544 if (so == NULL) 545 sp = ipsec4_getpolicybyaddr(m, IPSEC_DIR_OUTBOUND, flags, &error); 546 else 547 sp = ipsec4_getpolicybysock(m, IPSEC_DIR_OUTBOUND, so, &error); 548 549 if (sp == NULL) { 550 ipsecstat.out_inval++; 551 goto bad; 552 } 553 554 error = 0; 555 556 /* check policy */ 557 switch (sp->policy) { 558 case IPSEC_POLICY_DISCARD: 559 /* 560 * This packet is just discarded. 561 */ 562 ipsecstat.out_polvio++; 563 goto bad; 564 565 case IPSEC_POLICY_BYPASS: 566 case IPSEC_POLICY_NONE: 567 case IPSEC_POLICY_TCP: 568 /* no need to do IPsec. */ 569 goto skip_ipsec; 570 571 case IPSEC_POLICY_IPSEC: 572 if (sp->req == NULL) { 573 /* acquire a policy */ 574 error = key_spdacquire(sp); 575 goto bad; 576 } 577 break; 578 579 case IPSEC_POLICY_ENTRUST: 580 default: 581 kprintf("ip_output: Invalid policy found. %d\n", sp->policy); 582 } 583 { 584 struct ipsec_output_state state; 585 bzero(&state, sizeof state); 586 state.m = m; 587 if (flags & IP_ROUTETOIF) { 588 state.ro = &iproute; 589 bzero(&iproute, sizeof iproute); 590 } else 591 state.ro = ro; 592 state.dst = (struct sockaddr *)dst; 593 594 ip->ip_sum = 0; 595 596 /* 597 * XXX 598 * delayed checksums are not currently compatible with IPsec 599 */ 600 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) { 601 in_delayed_cksum(m); 602 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA; 603 } 604 605 ip->ip_len = htons(ip->ip_len); 606 ip->ip_off = htons(ip->ip_off); 607 608 error = ipsec4_output(&state, sp, flags); 609 610 m = state.m; 611 if (flags & IP_ROUTETOIF) { 612 /* 613 * if we have tunnel mode SA, we may need to ignore 614 * IP_ROUTETOIF. 615 */ 616 if (state.ro != &iproute || state.ro->ro_rt != NULL) { 617 flags &= ~IP_ROUTETOIF; 618 ro = state.ro; 619 } 620 } else 621 ro = state.ro; 622 dst = (struct sockaddr_in *)state.dst; 623 if (error) { 624 /* mbuf is already reclaimed in ipsec4_output. */ 625 m0 = NULL; 626 switch (error) { 627 case EHOSTUNREACH: 628 case ENETUNREACH: 629 case EMSGSIZE: 630 case ENOBUFS: 631 case ENOMEM: 632 break; 633 default: 634 kprintf("ip4_output (ipsec): error code %d\n", error); 635 /*fall through*/ 636 case ENOENT: 637 /* don't show these error codes to the user */ 638 error = 0; 639 break; 640 } 641 goto bad; 642 } 643 } 644 645 /* be sure to update variables that are affected by ipsec4_output() */ 646 ip = mtod(m, struct ip *); 647 #ifdef _IP_VHL 648 hlen = IP_VHL_HL(ip->ip_vhl) << 2; 649 #else 650 hlen = ip->ip_hl << 2; 651 #endif 652 if (ro->ro_rt == NULL) { 653 if (!(flags & IP_ROUTETOIF)) { 654 kprintf("ip_output: " 655 "can't update route after IPsec processing\n"); 656 error = EHOSTUNREACH; /*XXX*/ 657 goto bad; 658 } 659 } else { 660 ia = ifatoia(ro->ro_rt->rt_ifa); 661 ifp = ro->ro_rt->rt_ifp; 662 } 663 664 /* make it flipped, again. */ 665 ip->ip_len = ntohs(ip->ip_len); 666 ip->ip_off = ntohs(ip->ip_off); 667 skip_ipsec: 668 #endif /*IPSEC*/ 669 #ifdef FAST_IPSEC 670 /* 671 * Check the security policy (SP) for the packet and, if 672 * required, do IPsec-related processing. There are two 673 * cases here; the first time a packet is sent through 674 * it will be untagged and handled by ipsec4_checkpolicy. 675 * If the packet is resubmitted to ip_output (e.g. after 676 * AH, ESP, etc. processing), there will be a tag to bypass 677 * the lookup and related policy checking. 678 */ 679 mtag = m_tag_find(m, PACKET_TAG_IPSEC_PENDING_TDB, NULL); 680 crit_enter(); 681 if (mtag != NULL) { 682 tdbi = (struct tdb_ident *)m_tag_data(mtag); 683 sp = ipsec_getpolicy(tdbi, IPSEC_DIR_OUTBOUND); 684 if (sp == NULL) 685 error = -EINVAL; /* force silent drop */ 686 m_tag_delete(m, mtag); 687 } else { 688 sp = ipsec4_checkpolicy(m, IPSEC_DIR_OUTBOUND, flags, 689 &error, inp); 690 } 691 /* 692 * There are four return cases: 693 * sp != NULL apply IPsec policy 694 * sp == NULL, error == 0 no IPsec handling needed 695 * sp == NULL, error == -EINVAL discard packet w/o error 696 * sp == NULL, error != 0 discard packet, report error 697 */ 698 if (sp != NULL) { 699 /* Loop detection, check if ipsec processing already done */ 700 KASSERT(sp->req != NULL, ("ip_output: no ipsec request")); 701 for (mtag = m_tag_first(m); mtag != NULL; 702 mtag = m_tag_next(m, mtag)) { 703 if (mtag->m_tag_cookie != MTAG_ABI_COMPAT) 704 continue; 705 if (mtag->m_tag_id != PACKET_TAG_IPSEC_OUT_DONE && 706 mtag->m_tag_id != PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED) 707 continue; 708 /* 709 * Check if policy has an SA associated with it. 710 * This can happen when an SP has yet to acquire 711 * an SA; e.g. on first reference. If it occurs, 712 * then we let ipsec4_process_packet do its thing. 713 */ 714 if (sp->req->sav == NULL) 715 break; 716 tdbi = (struct tdb_ident *)m_tag_data(mtag); 717 if (tdbi->spi == sp->req->sav->spi && 718 tdbi->proto == sp->req->sav->sah->saidx.proto && 719 bcmp(&tdbi->dst, &sp->req->sav->sah->saidx.dst, 720 sizeof(union sockaddr_union)) == 0) { 721 /* 722 * No IPsec processing is needed, free 723 * reference to SP. 724 * 725 * NB: null pointer to avoid free at 726 * done: below. 727 */ 728 KEY_FREESP(&sp), sp = NULL; 729 crit_exit(); 730 goto spd_done; 731 } 732 } 733 734 /* 735 * Do delayed checksums now because we send before 736 * this is done in the normal processing path. 737 */ 738 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) { 739 in_delayed_cksum(m); 740 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA; 741 } 742 743 ip->ip_len = htons(ip->ip_len); 744 ip->ip_off = htons(ip->ip_off); 745 746 /* NB: callee frees mbuf */ 747 error = ipsec4_process_packet(m, sp->req, flags, 0); 748 /* 749 * Preserve KAME behaviour: ENOENT can be returned 750 * when an SA acquire is in progress. Don't propagate 751 * this to user-level; it confuses applications. 752 * 753 * XXX this will go away when the SADB is redone. 754 */ 755 if (error == ENOENT) 756 error = 0; 757 crit_exit(); 758 goto done; 759 } else { 760 crit_exit(); 761 762 if (error != 0) { 763 /* 764 * Hack: -EINVAL is used to signal that a packet 765 * should be silently discarded. This is typically 766 * because we asked key management for an SA and 767 * it was delayed (e.g. kicked up to IKE). 768 */ 769 if (error == -EINVAL) 770 error = 0; 771 goto bad; 772 } else { 773 /* No IPsec processing for this packet. */ 774 } 775 #ifdef notyet 776 /* 777 * If deferred crypto processing is needed, check that 778 * the interface supports it. 779 */ 780 mtag = m_tag_find(m, PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED, NULL); 781 if (mtag != NULL && !(ifp->if_capenable & IFCAP_IPSEC)) { 782 /* notify IPsec to do its own crypto */ 783 ipsp_skipcrypto_unmark((struct tdb_ident *)m_tag_data(mtag)); 784 error = EHOSTUNREACH; 785 goto bad; 786 } 787 #endif 788 } 789 spd_done: 790 #endif /* FAST_IPSEC */ 791 792 /* We are already being fwd'd from a firewall. */ 793 if (next_hop != NULL) 794 goto pass; 795 796 /* No pfil hooks */ 797 if (!pfil_has_hooks(&inet_pfil_hook)) { 798 if (m->m_pkthdr.fw_flags & DUMMYNET_MBUF_TAGGED) { 799 /* 800 * Strip dummynet tags from stranded packets 801 */ 802 mtag = m_tag_find(m, PACKET_TAG_DUMMYNET, NULL); 803 KKASSERT(mtag != NULL); 804 m_tag_delete(m, mtag); 805 m->m_pkthdr.fw_flags &= ~DUMMYNET_MBUF_TAGGED; 806 } 807 goto pass; 808 } 809 810 /* 811 * IpHack's section. 812 * - Xlate: translate packet's addr/port (NAT). 813 * - Firewall: deny/allow/etc. 814 * - Wrap: fake packet's addr/port <unimpl.> 815 * - Encapsulate: put it in another IP and send out. <unimp.> 816 */ 817 818 /* 819 * Run through list of hooks for output packets. 820 */ 821 error = pfil_run_hooks(&inet_pfil_hook, &m, ifp, PFIL_OUT); 822 if (error != 0 || m == NULL) 823 goto done; 824 ip = mtod(m, struct ip *); 825 826 if (m->m_pkthdr.fw_flags & IPFORWARD_MBUF_TAGGED) { 827 /* 828 * Check dst to make sure it is directly reachable on the 829 * interface we previously thought it was. 830 * If it isn't (which may be likely in some situations) we have 831 * to re-route it (ie, find a route for the next-hop and the 832 * associated interface) and set them here. This is nested 833 * forwarding which in most cases is undesirable, except where 834 * such control is nigh impossible. So we do it here. 835 * And I'm babbling. 836 */ 837 mtag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL); 838 KKASSERT(mtag != NULL); 839 next_hop = m_tag_data(mtag); 840 841 /* 842 * Try local forwarding first 843 */ 844 if (ip_localforward(m, next_hop, hlen)) 845 goto done; 846 847 /* 848 * Relocate the route based on next_hop. 849 * If the current route is inp's cache, keep it untouched. 850 */ 851 if (ro == &iproute && ro->ro_rt != NULL) { 852 RTFREE(ro->ro_rt); 853 ro->ro_rt = NULL; 854 } 855 ro = &iproute; 856 bzero(ro, sizeof *ro); 857 858 /* 859 * Forwarding to broadcast address is not allowed. 860 * XXX Should we follow IP_ROUTETOIF? 861 */ 862 flags &= ~(IP_ALLOWBROADCAST | IP_ROUTETOIF); 863 864 /* We are doing forwarding now */ 865 flags |= IP_FORWARDING; 866 867 goto reroute; 868 } 869 870 if (m->m_pkthdr.fw_flags & DUMMYNET_MBUF_TAGGED) { 871 struct dn_pkt *dn_pkt; 872 873 mtag = m_tag_find(m, PACKET_TAG_DUMMYNET, NULL); 874 KKASSERT(mtag != NULL); 875 dn_pkt = m_tag_data(mtag); 876 877 /* 878 * Under certain cases it is not possible to recalculate 879 * 'ro' and 'dst', let alone 'flags', so just save them in 880 * dummynet tag and avoid the possible wrong reculcalation 881 * when we come back to ip_output() again. 882 * 883 * All other parameters have been already used and so they 884 * are not needed anymore. 885 * XXX if the ifp is deleted while a pkt is in dummynet, 886 * we are in trouble! (TODO use ifnet_detach_event) 887 * 888 * We need to copy *ro because for ICMP pkts (and maybe 889 * others) the caller passed a pointer into the stack; 890 * dst might also be a pointer into *ro so it needs to 891 * be updated. 892 */ 893 dn_pkt->ro = *ro; 894 if (ro->ro_rt) 895 ro->ro_rt->rt_refcnt++; 896 if (dst == (struct sockaddr_in *)&ro->ro_dst) { 897 /* 'dst' points into 'ro' */ 898 dst = (struct sockaddr_in *)&(dn_pkt->ro.ro_dst); 899 } 900 dn_pkt->dn_dst = dst; 901 dn_pkt->flags = flags; 902 903 ip_dn_queue(m); 904 goto done; 905 } 906 pass: 907 /* 127/8 must not appear on wire - RFC1122. */ 908 if ((ntohl(ip->ip_dst.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET || 909 (ntohl(ip->ip_src.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET) { 910 if (!(ifp->if_flags & IFF_LOOPBACK)) { 911 ipstat.ips_badaddr++; 912 error = EADDRNOTAVAIL; 913 goto bad; 914 } 915 } 916 917 m->m_pkthdr.csum_flags |= CSUM_IP; 918 sw_csum = m->m_pkthdr.csum_flags & ~ifp->if_hwassist; 919 if (sw_csum & CSUM_DELAY_DATA) { 920 in_delayed_cksum(m); 921 sw_csum &= ~CSUM_DELAY_DATA; 922 } 923 m->m_pkthdr.csum_flags &= ifp->if_hwassist; 924 925 /* 926 * If small enough for interface, or the interface will take 927 * care of the fragmentation for us, can just send directly. 928 */ 929 if (ip->ip_len <= ifp->if_mtu || ((ifp->if_hwassist & CSUM_FRAGMENT) && 930 !(ip->ip_off & IP_DF))) { 931 ip->ip_len = htons(ip->ip_len); 932 ip->ip_off = htons(ip->ip_off); 933 ip->ip_sum = 0; 934 if (sw_csum & CSUM_DELAY_IP) { 935 if (ip->ip_vhl == IP_VHL_BORING) 936 ip->ip_sum = in_cksum_hdr(ip); 937 else 938 ip->ip_sum = in_cksum(m, hlen); 939 } 940 941 /* Record statistics for this interface address. */ 942 if (!(flags & IP_FORWARDING) && ia) { 943 ia->ia_ifa.if_opackets++; 944 ia->ia_ifa.if_obytes += m->m_pkthdr.len; 945 } 946 947 #ifdef IPSEC 948 /* clean ipsec history once it goes out of the node */ 949 ipsec_delaux(m); 950 #endif 951 952 #ifdef MBUF_STRESS_TEST 953 if (mbuf_frag_size && m->m_pkthdr.len > mbuf_frag_size) { 954 struct mbuf *m1, *m2; 955 int length, tmp; 956 957 tmp = length = m->m_pkthdr.len; 958 959 while ((length -= mbuf_frag_size) >= 1) { 960 m1 = m_split(m, length, MB_DONTWAIT); 961 if (m1 == NULL) 962 break; 963 m2 = m; 964 while (m2->m_next != NULL) 965 m2 = m2->m_next; 966 m2->m_next = m1; 967 } 968 m->m_pkthdr.len = tmp; 969 } 970 #endif 971 972 #ifdef MPLS 973 if (!mpls_output_process(m, ro->ro_rt)) 974 goto done; 975 #endif 976 error = ifp->if_output(ifp, m, (struct sockaddr *)dst, 977 ro->ro_rt); 978 goto done; 979 } 980 981 if (ip->ip_off & IP_DF) { 982 error = EMSGSIZE; 983 /* 984 * This case can happen if the user changed the MTU 985 * of an interface after enabling IP on it. Because 986 * most netifs don't keep track of routes pointing to 987 * them, there is no way for one to update all its 988 * routes when the MTU is changed. 989 */ 990 if ((ro->ro_rt->rt_flags & (RTF_UP | RTF_HOST)) && 991 !(ro->ro_rt->rt_rmx.rmx_locks & RTV_MTU) && 992 (ro->ro_rt->rt_rmx.rmx_mtu > ifp->if_mtu)) { 993 ro->ro_rt->rt_rmx.rmx_mtu = ifp->if_mtu; 994 } 995 ipstat.ips_cantfrag++; 996 goto bad; 997 } 998 999 /* 1000 * Too large for interface; fragment if possible. If successful, 1001 * on return, m will point to a list of packets to be sent. 1002 */ 1003 error = ip_fragment(ip, &m, ifp->if_mtu, ifp->if_hwassist, sw_csum); 1004 if (error) 1005 goto bad; 1006 for (; m; m = m0) { 1007 m0 = m->m_nextpkt; 1008 m->m_nextpkt = NULL; 1009 #ifdef IPSEC 1010 /* clean ipsec history once it goes out of the node */ 1011 ipsec_delaux(m); 1012 #endif 1013 if (error == 0) { 1014 /* Record statistics for this interface address. */ 1015 if (ia != NULL) { 1016 ia->ia_ifa.if_opackets++; 1017 ia->ia_ifa.if_obytes += m->m_pkthdr.len; 1018 } 1019 #ifdef MPLS 1020 if (!mpls_output_process(m, ro->ro_rt)) 1021 continue; 1022 #endif 1023 error = ifp->if_output(ifp, m, (struct sockaddr *)dst, 1024 ro->ro_rt); 1025 } else { 1026 m_freem(m); 1027 } 1028 } 1029 1030 if (error == 0) 1031 ipstat.ips_fragmented++; 1032 1033 done: 1034 if (ro == &iproute && ro->ro_rt != NULL) { 1035 RTFREE(ro->ro_rt); 1036 ro->ro_rt = NULL; 1037 } 1038 #ifdef IPSEC 1039 if (sp != NULL) { 1040 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 1041 kprintf("DP ip_output call free SP:%p\n", sp)); 1042 key_freesp(sp); 1043 } 1044 #endif 1045 #ifdef FAST_IPSEC 1046 if (sp != NULL) 1047 KEY_FREESP(&sp); 1048 #endif 1049 return (error); 1050 bad: 1051 m_freem(m); 1052 goto done; 1053 } 1054 1055 /* 1056 * Create a chain of fragments which fit the given mtu. m_frag points to the 1057 * mbuf to be fragmented; on return it points to the chain with the fragments. 1058 * Return 0 if no error. If error, m_frag may contain a partially built 1059 * chain of fragments that should be freed by the caller. 1060 * 1061 * if_hwassist_flags is the hw offload capabilities (see if_data.ifi_hwassist) 1062 * sw_csum contains the delayed checksums flags (e.g., CSUM_DELAY_IP). 1063 */ 1064 int 1065 ip_fragment(struct ip *ip, struct mbuf **m_frag, int mtu, 1066 u_long if_hwassist_flags, int sw_csum) 1067 { 1068 int error = 0; 1069 int hlen = IP_VHL_HL(ip->ip_vhl) << 2; 1070 int len = (mtu - hlen) & ~7; /* size of payload in each fragment */ 1071 int off; 1072 struct mbuf *m0 = *m_frag; /* the original packet */ 1073 int firstlen; 1074 struct mbuf **mnext; 1075 int nfrags; 1076 1077 if (ip->ip_off & IP_DF) { /* Fragmentation not allowed */ 1078 ipstat.ips_cantfrag++; 1079 return EMSGSIZE; 1080 } 1081 1082 /* 1083 * Must be able to put at least 8 bytes per fragment. 1084 */ 1085 if (len < 8) 1086 return EMSGSIZE; 1087 1088 /* 1089 * If the interface will not calculate checksums on 1090 * fragmented packets, then do it here. 1091 */ 1092 if ((m0->m_pkthdr.csum_flags & CSUM_DELAY_DATA) && 1093 !(if_hwassist_flags & CSUM_IP_FRAGS)) { 1094 in_delayed_cksum(m0); 1095 m0->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA; 1096 } 1097 1098 if (len > PAGE_SIZE) { 1099 /* 1100 * Fragment large datagrams such that each segment 1101 * contains a multiple of PAGE_SIZE amount of data, 1102 * plus headers. This enables a receiver to perform 1103 * page-flipping zero-copy optimizations. 1104 * 1105 * XXX When does this help given that sender and receiver 1106 * could have different page sizes, and also mtu could 1107 * be less than the receiver's page size ? 1108 */ 1109 int newlen; 1110 struct mbuf *m; 1111 1112 for (m = m0, off = 0; m && (off+m->m_len) <= mtu; m = m->m_next) 1113 off += m->m_len; 1114 1115 /* 1116 * firstlen (off - hlen) must be aligned on an 1117 * 8-byte boundary 1118 */ 1119 if (off < hlen) 1120 goto smart_frag_failure; 1121 off = ((off - hlen) & ~7) + hlen; 1122 newlen = (~PAGE_MASK) & mtu; 1123 if ((newlen + sizeof(struct ip)) > mtu) { 1124 /* we failed, go back the default */ 1125 smart_frag_failure: 1126 newlen = len; 1127 off = hlen + len; 1128 } 1129 len = newlen; 1130 1131 } else { 1132 off = hlen + len; 1133 } 1134 1135 firstlen = off - hlen; 1136 mnext = &m0->m_nextpkt; /* pointer to next packet */ 1137 1138 /* 1139 * Loop through length of segment after first fragment, 1140 * make new header and copy data of each part and link onto chain. 1141 * Here, m0 is the original packet, m is the fragment being created. 1142 * The fragments are linked off the m_nextpkt of the original 1143 * packet, which after processing serves as the first fragment. 1144 */ 1145 for (nfrags = 1; off < ip->ip_len; off += len, nfrags++) { 1146 struct ip *mhip; /* ip header on the fragment */ 1147 struct mbuf *m; 1148 int mhlen = sizeof(struct ip); 1149 1150 MGETHDR(m, MB_DONTWAIT, MT_HEADER); 1151 if (m == NULL) { 1152 error = ENOBUFS; 1153 ipstat.ips_odropped++; 1154 goto done; 1155 } 1156 m->m_flags |= (m0->m_flags & M_MCAST) | M_FRAG; 1157 /* 1158 * In the first mbuf, leave room for the link header, then 1159 * copy the original IP header including options. The payload 1160 * goes into an additional mbuf chain returned by m_copy(). 1161 */ 1162 m->m_data += max_linkhdr; 1163 mhip = mtod(m, struct ip *); 1164 *mhip = *ip; 1165 if (hlen > sizeof(struct ip)) { 1166 mhlen = ip_optcopy(ip, mhip) + sizeof(struct ip); 1167 mhip->ip_vhl = IP_MAKE_VHL(IPVERSION, mhlen >> 2); 1168 } 1169 m->m_len = mhlen; 1170 /* XXX do we need to add ip->ip_off below ? */ 1171 mhip->ip_off = ((off - hlen) >> 3) + ip->ip_off; 1172 if (off + len >= ip->ip_len) { /* last fragment */ 1173 len = ip->ip_len - off; 1174 m->m_flags |= M_LASTFRAG; 1175 } else 1176 mhip->ip_off |= IP_MF; 1177 mhip->ip_len = htons((u_short)(len + mhlen)); 1178 m->m_next = m_copy(m0, off, len); 1179 if (m->m_next == NULL) { /* copy failed */ 1180 m_free(m); 1181 error = ENOBUFS; /* ??? */ 1182 ipstat.ips_odropped++; 1183 goto done; 1184 } 1185 m->m_pkthdr.len = mhlen + len; 1186 m->m_pkthdr.rcvif = NULL; 1187 m->m_pkthdr.csum_flags = m0->m_pkthdr.csum_flags; 1188 mhip->ip_off = htons(mhip->ip_off); 1189 mhip->ip_sum = 0; 1190 if (sw_csum & CSUM_DELAY_IP) 1191 mhip->ip_sum = in_cksum(m, mhlen); 1192 *mnext = m; 1193 mnext = &m->m_nextpkt; 1194 } 1195 ipstat.ips_ofragments += nfrags; 1196 1197 /* set first marker for fragment chain */ 1198 m0->m_flags |= M_FIRSTFRAG | M_FRAG; 1199 m0->m_pkthdr.csum_data = nfrags; 1200 1201 /* 1202 * Update first fragment by trimming what's been copied out 1203 * and updating header. 1204 */ 1205 m_adj(m0, hlen + firstlen - ip->ip_len); 1206 m0->m_pkthdr.len = hlen + firstlen; 1207 ip->ip_len = htons((u_short)m0->m_pkthdr.len); 1208 ip->ip_off |= IP_MF; 1209 ip->ip_off = htons(ip->ip_off); 1210 ip->ip_sum = 0; 1211 if (sw_csum & CSUM_DELAY_IP) 1212 ip->ip_sum = in_cksum(m0, hlen); 1213 1214 done: 1215 *m_frag = m0; 1216 return error; 1217 } 1218 1219 void 1220 in_delayed_cksum(struct mbuf *m) 1221 { 1222 struct ip *ip; 1223 u_short csum, offset; 1224 1225 ip = mtod(m, struct ip *); 1226 offset = IP_VHL_HL(ip->ip_vhl) << 2 ; 1227 csum = in_cksum_skip(m, ip->ip_len, offset); 1228 if (m->m_pkthdr.csum_flags & CSUM_UDP && csum == 0) 1229 csum = 0xffff; 1230 offset += m->m_pkthdr.csum_data; /* checksum offset */ 1231 1232 if (offset + sizeof(u_short) > m->m_len) { 1233 kprintf("delayed m_pullup, m->len: %d off: %d p: %d\n", 1234 m->m_len, offset, ip->ip_p); 1235 /* 1236 * XXX 1237 * this shouldn't happen, but if it does, the 1238 * correct behavior may be to insert the checksum 1239 * in the existing chain instead of rearranging it. 1240 */ 1241 m = m_pullup(m, offset + sizeof(u_short)); 1242 } 1243 *(u_short *)(m->m_data + offset) = csum; 1244 } 1245 1246 /* 1247 * Insert IP options into preformed packet. 1248 * Adjust IP destination as required for IP source routing, 1249 * as indicated by a non-zero in_addr at the start of the options. 1250 * 1251 * XXX This routine assumes that the packet has no options in place. 1252 */ 1253 static struct mbuf * 1254 ip_insertoptions(struct mbuf *m, struct mbuf *opt, int *phlen) 1255 { 1256 struct ipoption *p = mtod(opt, struct ipoption *); 1257 struct mbuf *n; 1258 struct ip *ip = mtod(m, struct ip *); 1259 unsigned optlen; 1260 1261 optlen = opt->m_len - sizeof p->ipopt_dst; 1262 if (optlen + (u_short)ip->ip_len > IP_MAXPACKET) { 1263 *phlen = 0; 1264 return (m); /* XXX should fail */ 1265 } 1266 if (p->ipopt_dst.s_addr) 1267 ip->ip_dst = p->ipopt_dst; 1268 if (m->m_flags & M_EXT || m->m_data - optlen < m->m_pktdat) { 1269 MGETHDR(n, MB_DONTWAIT, MT_HEADER); 1270 if (n == NULL) { 1271 *phlen = 0; 1272 return (m); 1273 } 1274 n->m_pkthdr.rcvif = NULL; 1275 n->m_pkthdr.len = m->m_pkthdr.len + optlen; 1276 m->m_len -= sizeof(struct ip); 1277 m->m_data += sizeof(struct ip); 1278 n->m_next = m; 1279 m = n; 1280 m->m_len = optlen + sizeof(struct ip); 1281 m->m_data += max_linkhdr; 1282 memcpy(mtod(m, void *), ip, sizeof(struct ip)); 1283 } else { 1284 m->m_data -= optlen; 1285 m->m_len += optlen; 1286 m->m_pkthdr.len += optlen; 1287 ovbcopy(ip, mtod(m, caddr_t), sizeof(struct ip)); 1288 } 1289 ip = mtod(m, struct ip *); 1290 bcopy(p->ipopt_list, ip + 1, optlen); 1291 *phlen = sizeof(struct ip) + optlen; 1292 ip->ip_vhl = IP_MAKE_VHL(IPVERSION, *phlen >> 2); 1293 ip->ip_len += optlen; 1294 return (m); 1295 } 1296 1297 /* 1298 * Copy options from ip to jp, 1299 * omitting those not copied during fragmentation. 1300 */ 1301 int 1302 ip_optcopy(struct ip *ip, struct ip *jp) 1303 { 1304 u_char *cp, *dp; 1305 int opt, optlen, cnt; 1306 1307 cp = (u_char *)(ip + 1); 1308 dp = (u_char *)(jp + 1); 1309 cnt = (IP_VHL_HL(ip->ip_vhl) << 2) - sizeof(struct ip); 1310 for (; cnt > 0; cnt -= optlen, cp += optlen) { 1311 opt = cp[0]; 1312 if (opt == IPOPT_EOL) 1313 break; 1314 if (opt == IPOPT_NOP) { 1315 /* Preserve for IP mcast tunnel's LSRR alignment. */ 1316 *dp++ = IPOPT_NOP; 1317 optlen = 1; 1318 continue; 1319 } 1320 1321 KASSERT(cnt >= IPOPT_OLEN + sizeof *cp, 1322 ("ip_optcopy: malformed ipv4 option")); 1323 optlen = cp[IPOPT_OLEN]; 1324 KASSERT(optlen >= IPOPT_OLEN + sizeof *cp && optlen <= cnt, 1325 ("ip_optcopy: malformed ipv4 option")); 1326 1327 /* bogus lengths should have been caught by ip_dooptions */ 1328 if (optlen > cnt) 1329 optlen = cnt; 1330 if (IPOPT_COPIED(opt)) { 1331 bcopy(cp, dp, optlen); 1332 dp += optlen; 1333 } 1334 } 1335 for (optlen = dp - (u_char *)(jp+1); optlen & 0x3; optlen++) 1336 *dp++ = IPOPT_EOL; 1337 return (optlen); 1338 } 1339 1340 /* 1341 * IP socket option processing. 1342 */ 1343 void 1344 ip_ctloutput(netmsg_t msg) 1345 { 1346 struct socket *so = msg->base.nm_so; 1347 struct sockopt *sopt = msg->ctloutput.nm_sopt; 1348 struct inpcb *inp = so->so_pcb; 1349 int error, optval; 1350 1351 error = optval = 0; 1352 if (sopt->sopt_level != IPPROTO_IP) { 1353 error = EINVAL; 1354 goto done; 1355 } 1356 1357 switch (sopt->sopt_dir) { 1358 case SOPT_SET: 1359 switch (sopt->sopt_name) { 1360 case IP_OPTIONS: 1361 #ifdef notyet 1362 case IP_RETOPTS: 1363 #endif 1364 { 1365 struct mbuf *m; 1366 if (sopt->sopt_valsize > MLEN) { 1367 error = EMSGSIZE; 1368 break; 1369 } 1370 MGET(m, sopt->sopt_td ? MB_WAIT : MB_DONTWAIT, MT_HEADER); 1371 if (m == NULL) { 1372 error = ENOBUFS; 1373 break; 1374 } 1375 m->m_len = sopt->sopt_valsize; 1376 error = soopt_to_kbuf(sopt, mtod(m, void *), m->m_len, 1377 m->m_len); 1378 error = ip_pcbopts(sopt->sopt_name, 1379 &inp->inp_options, m); 1380 goto done; 1381 } 1382 1383 case IP_TOS: 1384 case IP_TTL: 1385 case IP_MINTTL: 1386 case IP_RECVOPTS: 1387 case IP_RECVRETOPTS: 1388 case IP_RECVDSTADDR: 1389 case IP_RECVIF: 1390 case IP_RECVTTL: 1391 case IP_FAITH: 1392 error = soopt_to_kbuf(sopt, &optval, sizeof optval, 1393 sizeof optval); 1394 if (error) 1395 break; 1396 switch (sopt->sopt_name) { 1397 case IP_TOS: 1398 inp->inp_ip_tos = optval; 1399 break; 1400 1401 case IP_TTL: 1402 inp->inp_ip_ttl = optval; 1403 break; 1404 case IP_MINTTL: 1405 if (optval >= 0 && optval <= MAXTTL) 1406 inp->inp_ip_minttl = optval; 1407 else 1408 error = EINVAL; 1409 break; 1410 #define OPTSET(bit) \ 1411 if (optval) \ 1412 inp->inp_flags |= bit; \ 1413 else \ 1414 inp->inp_flags &= ~bit; 1415 1416 case IP_RECVOPTS: 1417 OPTSET(INP_RECVOPTS); 1418 break; 1419 1420 case IP_RECVRETOPTS: 1421 OPTSET(INP_RECVRETOPTS); 1422 break; 1423 1424 case IP_RECVDSTADDR: 1425 OPTSET(INP_RECVDSTADDR); 1426 break; 1427 1428 case IP_RECVIF: 1429 OPTSET(INP_RECVIF); 1430 break; 1431 1432 case IP_RECVTTL: 1433 OPTSET(INP_RECVTTL); 1434 break; 1435 1436 case IP_FAITH: 1437 OPTSET(INP_FAITH); 1438 break; 1439 } 1440 break; 1441 #undef OPTSET 1442 1443 case IP_MULTICAST_IF: 1444 case IP_MULTICAST_VIF: 1445 case IP_MULTICAST_TTL: 1446 case IP_MULTICAST_LOOP: 1447 case IP_ADD_MEMBERSHIP: 1448 case IP_DROP_MEMBERSHIP: 1449 error = ip_setmoptions(sopt, &inp->inp_moptions); 1450 break; 1451 1452 case IP_PORTRANGE: 1453 error = soopt_to_kbuf(sopt, &optval, sizeof optval, 1454 sizeof optval); 1455 if (error) 1456 break; 1457 1458 switch (optval) { 1459 case IP_PORTRANGE_DEFAULT: 1460 inp->inp_flags &= ~(INP_LOWPORT); 1461 inp->inp_flags &= ~(INP_HIGHPORT); 1462 break; 1463 1464 case IP_PORTRANGE_HIGH: 1465 inp->inp_flags &= ~(INP_LOWPORT); 1466 inp->inp_flags |= INP_HIGHPORT; 1467 break; 1468 1469 case IP_PORTRANGE_LOW: 1470 inp->inp_flags &= ~(INP_HIGHPORT); 1471 inp->inp_flags |= INP_LOWPORT; 1472 break; 1473 1474 default: 1475 error = EINVAL; 1476 break; 1477 } 1478 break; 1479 1480 #if defined(IPSEC) || defined(FAST_IPSEC) 1481 case IP_IPSEC_POLICY: 1482 { 1483 caddr_t req; 1484 size_t len = 0; 1485 int priv; 1486 struct mbuf *m; 1487 int optname; 1488 1489 if ((error = soopt_getm(sopt, &m)) != 0) /* XXX */ 1490 break; 1491 soopt_to_mbuf(sopt, m); 1492 priv = (sopt->sopt_td != NULL && 1493 priv_check(sopt->sopt_td, PRIV_ROOT) != 0) ? 0 : 1; 1494 req = mtod(m, caddr_t); 1495 len = m->m_len; 1496 optname = sopt->sopt_name; 1497 error = ipsec4_set_policy(inp, optname, req, len, priv); 1498 m_freem(m); 1499 break; 1500 } 1501 #endif /*IPSEC*/ 1502 1503 default: 1504 error = ENOPROTOOPT; 1505 break; 1506 } 1507 break; 1508 1509 case SOPT_GET: 1510 switch (sopt->sopt_name) { 1511 case IP_OPTIONS: 1512 case IP_RETOPTS: 1513 if (inp->inp_options) 1514 soopt_from_kbuf(sopt, mtod(inp->inp_options, 1515 char *), 1516 inp->inp_options->m_len); 1517 else 1518 sopt->sopt_valsize = 0; 1519 break; 1520 1521 case IP_TOS: 1522 case IP_TTL: 1523 case IP_MINTTL: 1524 case IP_RECVOPTS: 1525 case IP_RECVRETOPTS: 1526 case IP_RECVDSTADDR: 1527 case IP_RECVTTL: 1528 case IP_RECVIF: 1529 case IP_PORTRANGE: 1530 case IP_FAITH: 1531 switch (sopt->sopt_name) { 1532 1533 case IP_TOS: 1534 optval = inp->inp_ip_tos; 1535 break; 1536 1537 case IP_TTL: 1538 optval = inp->inp_ip_ttl; 1539 break; 1540 case IP_MINTTL: 1541 optval = inp->inp_ip_minttl; 1542 break; 1543 1544 #define OPTBIT(bit) (inp->inp_flags & bit ? 1 : 0) 1545 1546 case IP_RECVOPTS: 1547 optval = OPTBIT(INP_RECVOPTS); 1548 break; 1549 1550 case IP_RECVRETOPTS: 1551 optval = OPTBIT(INP_RECVRETOPTS); 1552 break; 1553 1554 case IP_RECVDSTADDR: 1555 optval = OPTBIT(INP_RECVDSTADDR); 1556 break; 1557 1558 case IP_RECVTTL: 1559 optval = OPTBIT(INP_RECVTTL); 1560 break; 1561 1562 case IP_RECVIF: 1563 optval = OPTBIT(INP_RECVIF); 1564 break; 1565 1566 case IP_PORTRANGE: 1567 if (inp->inp_flags & INP_HIGHPORT) 1568 optval = IP_PORTRANGE_HIGH; 1569 else if (inp->inp_flags & INP_LOWPORT) 1570 optval = IP_PORTRANGE_LOW; 1571 else 1572 optval = 0; 1573 break; 1574 1575 case IP_FAITH: 1576 optval = OPTBIT(INP_FAITH); 1577 break; 1578 } 1579 soopt_from_kbuf(sopt, &optval, sizeof optval); 1580 break; 1581 1582 case IP_MULTICAST_IF: 1583 case IP_MULTICAST_VIF: 1584 case IP_MULTICAST_TTL: 1585 case IP_MULTICAST_LOOP: 1586 case IP_ADD_MEMBERSHIP: 1587 case IP_DROP_MEMBERSHIP: 1588 error = ip_getmoptions(sopt, inp->inp_moptions); 1589 break; 1590 1591 #if defined(IPSEC) || defined(FAST_IPSEC) 1592 case IP_IPSEC_POLICY: 1593 { 1594 struct mbuf *m = NULL; 1595 caddr_t req = NULL; 1596 size_t len = 0; 1597 1598 if (m != NULL) { 1599 req = mtod(m, caddr_t); 1600 len = m->m_len; 1601 } 1602 error = ipsec4_get_policy(so->so_pcb, req, len, &m); 1603 if (error == 0) 1604 error = soopt_from_mbuf(sopt, m); /* XXX */ 1605 if (error == 0) 1606 m_freem(m); 1607 break; 1608 } 1609 #endif /*IPSEC*/ 1610 1611 default: 1612 error = ENOPROTOOPT; 1613 break; 1614 } 1615 break; 1616 } 1617 done: 1618 lwkt_replymsg(&msg->lmsg, error); 1619 } 1620 1621 /* 1622 * Set up IP options in pcb for insertion in output packets. 1623 * Store in mbuf with pointer in pcbopt, adding pseudo-option 1624 * with destination address if source routed. 1625 */ 1626 static int 1627 ip_pcbopts(int optname, struct mbuf **pcbopt, struct mbuf *m) 1628 { 1629 int cnt, optlen; 1630 u_char *cp; 1631 u_char opt; 1632 1633 /* turn off any old options */ 1634 if (*pcbopt) 1635 m_free(*pcbopt); 1636 *pcbopt = 0; 1637 if (m == NULL || m->m_len == 0) { 1638 /* 1639 * Only turning off any previous options. 1640 */ 1641 if (m != NULL) 1642 m_free(m); 1643 return (0); 1644 } 1645 1646 if (m->m_len % sizeof(int32_t)) 1647 goto bad; 1648 /* 1649 * IP first-hop destination address will be stored before 1650 * actual options; move other options back 1651 * and clear it when none present. 1652 */ 1653 if (m->m_data + m->m_len + sizeof(struct in_addr) >= &m->m_dat[MLEN]) 1654 goto bad; 1655 cnt = m->m_len; 1656 m->m_len += sizeof(struct in_addr); 1657 cp = mtod(m, u_char *) + sizeof(struct in_addr); 1658 ovbcopy(mtod(m, caddr_t), cp, cnt); 1659 bzero(mtod(m, caddr_t), sizeof(struct in_addr)); 1660 1661 for (; cnt > 0; cnt -= optlen, cp += optlen) { 1662 opt = cp[IPOPT_OPTVAL]; 1663 if (opt == IPOPT_EOL) 1664 break; 1665 if (opt == IPOPT_NOP) 1666 optlen = 1; 1667 else { 1668 if (cnt < IPOPT_OLEN + sizeof *cp) 1669 goto bad; 1670 optlen = cp[IPOPT_OLEN]; 1671 if (optlen < IPOPT_OLEN + sizeof *cp || optlen > cnt) 1672 goto bad; 1673 } 1674 switch (opt) { 1675 1676 default: 1677 break; 1678 1679 case IPOPT_LSRR: 1680 case IPOPT_SSRR: 1681 /* 1682 * user process specifies route as: 1683 * ->A->B->C->D 1684 * D must be our final destination (but we can't 1685 * check that since we may not have connected yet). 1686 * A is first hop destination, which doesn't appear in 1687 * actual IP option, but is stored before the options. 1688 */ 1689 if (optlen < IPOPT_MINOFF - 1 + sizeof(struct in_addr)) 1690 goto bad; 1691 m->m_len -= sizeof(struct in_addr); 1692 cnt -= sizeof(struct in_addr); 1693 optlen -= sizeof(struct in_addr); 1694 cp[IPOPT_OLEN] = optlen; 1695 /* 1696 * Move first hop before start of options. 1697 */ 1698 bcopy(&cp[IPOPT_OFFSET+1], mtod(m, caddr_t), 1699 sizeof(struct in_addr)); 1700 /* 1701 * Then copy rest of options back 1702 * to close up the deleted entry. 1703 */ 1704 ovbcopy(&cp[IPOPT_OFFSET+1] + sizeof(struct in_addr), 1705 &cp[IPOPT_OFFSET+1], 1706 cnt - (IPOPT_MINOFF - 1)); 1707 break; 1708 } 1709 } 1710 if (m->m_len > MAX_IPOPTLEN + sizeof(struct in_addr)) 1711 goto bad; 1712 *pcbopt = m; 1713 return (0); 1714 1715 bad: 1716 m_free(m); 1717 return (EINVAL); 1718 } 1719 1720 /* 1721 * XXX 1722 * The whole multicast option thing needs to be re-thought. 1723 * Several of these options are equally applicable to non-multicast 1724 * transmission, and one (IP_MULTICAST_TTL) totally duplicates a 1725 * standard option (IP_TTL). 1726 */ 1727 1728 /* 1729 * following RFC1724 section 3.3, 0.0.0.0/8 is interpreted as interface index. 1730 */ 1731 static struct ifnet * 1732 ip_multicast_if(struct in_addr *a, int *ifindexp) 1733 { 1734 int ifindex; 1735 struct ifnet *ifp; 1736 1737 if (ifindexp) 1738 *ifindexp = 0; 1739 if (ntohl(a->s_addr) >> 24 == 0) { 1740 ifindex = ntohl(a->s_addr) & 0xffffff; 1741 if (ifindex < 0 || if_index < ifindex) 1742 return NULL; 1743 ifp = ifindex2ifnet[ifindex]; 1744 if (ifindexp) 1745 *ifindexp = ifindex; 1746 } else { 1747 ifp = INADDR_TO_IFP(a); 1748 } 1749 return ifp; 1750 } 1751 1752 /* 1753 * Set the IP multicast options in response to user setsockopt(). 1754 */ 1755 static int 1756 ip_setmoptions(struct sockopt *sopt, struct ip_moptions **imop) 1757 { 1758 int error = 0; 1759 int i; 1760 struct in_addr addr; 1761 struct ip_mreq mreq; 1762 struct ifnet *ifp; 1763 struct ip_moptions *imo = *imop; 1764 int ifindex; 1765 1766 if (imo == NULL) { 1767 /* 1768 * No multicast option buffer attached to the pcb; 1769 * allocate one and initialize to default values. 1770 */ 1771 imo = kmalloc(sizeof *imo, M_IPMOPTS, M_WAITOK); 1772 1773 *imop = imo; 1774 imo->imo_multicast_ifp = NULL; 1775 imo->imo_multicast_addr.s_addr = INADDR_ANY; 1776 imo->imo_multicast_vif = -1; 1777 imo->imo_multicast_ttl = IP_DEFAULT_MULTICAST_TTL; 1778 imo->imo_multicast_loop = IP_DEFAULT_MULTICAST_LOOP; 1779 imo->imo_num_memberships = 0; 1780 } 1781 switch (sopt->sopt_name) { 1782 /* store an index number for the vif you wanna use in the send */ 1783 case IP_MULTICAST_VIF: 1784 if (legal_vif_num == 0) { 1785 error = EOPNOTSUPP; 1786 break; 1787 } 1788 error = soopt_to_kbuf(sopt, &i, sizeof i, sizeof i); 1789 if (error) 1790 break; 1791 if (!legal_vif_num(i) && (i != -1)) { 1792 error = EINVAL; 1793 break; 1794 } 1795 imo->imo_multicast_vif = i; 1796 break; 1797 1798 case IP_MULTICAST_IF: 1799 /* 1800 * Select the interface for outgoing multicast packets. 1801 */ 1802 error = soopt_to_kbuf(sopt, &addr, sizeof addr, sizeof addr); 1803 if (error) 1804 break; 1805 1806 /* 1807 * INADDR_ANY is used to remove a previous selection. 1808 * When no interface is selected, a default one is 1809 * chosen every time a multicast packet is sent. 1810 */ 1811 if (addr.s_addr == INADDR_ANY) { 1812 imo->imo_multicast_ifp = NULL; 1813 break; 1814 } 1815 /* 1816 * The selected interface is identified by its local 1817 * IP address. Find the interface and confirm that 1818 * it supports multicasting. 1819 */ 1820 crit_enter(); 1821 ifp = ip_multicast_if(&addr, &ifindex); 1822 if (ifp == NULL || !(ifp->if_flags & IFF_MULTICAST)) { 1823 crit_exit(); 1824 error = EADDRNOTAVAIL; 1825 break; 1826 } 1827 imo->imo_multicast_ifp = ifp; 1828 if (ifindex) 1829 imo->imo_multicast_addr = addr; 1830 else 1831 imo->imo_multicast_addr.s_addr = INADDR_ANY; 1832 crit_exit(); 1833 break; 1834 1835 case IP_MULTICAST_TTL: 1836 /* 1837 * Set the IP time-to-live for outgoing multicast packets. 1838 * The original multicast API required a char argument, 1839 * which is inconsistent with the rest of the socket API. 1840 * We allow either a char or an int. 1841 */ 1842 if (sopt->sopt_valsize == 1) { 1843 u_char ttl; 1844 error = soopt_to_kbuf(sopt, &ttl, 1, 1); 1845 if (error) 1846 break; 1847 imo->imo_multicast_ttl = ttl; 1848 } else { 1849 u_int ttl; 1850 error = soopt_to_kbuf(sopt, &ttl, sizeof ttl, sizeof ttl); 1851 if (error) 1852 break; 1853 if (ttl > 255) 1854 error = EINVAL; 1855 else 1856 imo->imo_multicast_ttl = ttl; 1857 } 1858 break; 1859 1860 case IP_MULTICAST_LOOP: 1861 /* 1862 * Set the loopback flag for outgoing multicast packets. 1863 * Must be zero or one. The original multicast API required a 1864 * char argument, which is inconsistent with the rest 1865 * of the socket API. We allow either a char or an int. 1866 */ 1867 if (sopt->sopt_valsize == 1) { 1868 u_char loop; 1869 1870 error = soopt_to_kbuf(sopt, &loop, 1, 1); 1871 if (error) 1872 break; 1873 imo->imo_multicast_loop = !!loop; 1874 } else { 1875 u_int loop; 1876 1877 error = soopt_to_kbuf(sopt, &loop, sizeof loop, 1878 sizeof loop); 1879 if (error) 1880 break; 1881 imo->imo_multicast_loop = !!loop; 1882 } 1883 break; 1884 1885 case IP_ADD_MEMBERSHIP: 1886 /* 1887 * Add a multicast group membership. 1888 * Group must be a valid IP multicast address. 1889 */ 1890 error = soopt_to_kbuf(sopt, &mreq, sizeof mreq, sizeof mreq); 1891 if (error) 1892 break; 1893 1894 if (!IN_MULTICAST(ntohl(mreq.imr_multiaddr.s_addr))) { 1895 error = EINVAL; 1896 break; 1897 } 1898 crit_enter(); 1899 /* 1900 * If no interface address was provided, use the interface of 1901 * the route to the given multicast address. 1902 */ 1903 if (mreq.imr_interface.s_addr == INADDR_ANY) { 1904 struct sockaddr_in dst; 1905 struct rtentry *rt; 1906 1907 bzero(&dst, sizeof(struct sockaddr_in)); 1908 dst.sin_len = sizeof(struct sockaddr_in); 1909 dst.sin_family = AF_INET; 1910 dst.sin_addr = mreq.imr_multiaddr; 1911 rt = rtlookup((struct sockaddr *)&dst); 1912 if (rt == NULL) { 1913 error = EADDRNOTAVAIL; 1914 crit_exit(); 1915 break; 1916 } 1917 --rt->rt_refcnt; 1918 ifp = rt->rt_ifp; 1919 } else { 1920 ifp = ip_multicast_if(&mreq.imr_interface, NULL); 1921 } 1922 1923 /* 1924 * See if we found an interface, and confirm that it 1925 * supports multicast. 1926 */ 1927 if (ifp == NULL || !(ifp->if_flags & IFF_MULTICAST)) { 1928 error = EADDRNOTAVAIL; 1929 crit_exit(); 1930 break; 1931 } 1932 /* 1933 * See if the membership already exists or if all the 1934 * membership slots are full. 1935 */ 1936 for (i = 0; i < imo->imo_num_memberships; ++i) { 1937 if (imo->imo_membership[i]->inm_ifp == ifp && 1938 imo->imo_membership[i]->inm_addr.s_addr 1939 == mreq.imr_multiaddr.s_addr) 1940 break; 1941 } 1942 if (i < imo->imo_num_memberships) { 1943 error = EADDRINUSE; 1944 crit_exit(); 1945 break; 1946 } 1947 if (i == IP_MAX_MEMBERSHIPS) { 1948 error = ETOOMANYREFS; 1949 crit_exit(); 1950 break; 1951 } 1952 /* 1953 * Everything looks good; add a new record to the multicast 1954 * address list for the given interface. 1955 */ 1956 if ((imo->imo_membership[i] = 1957 in_addmulti(&mreq.imr_multiaddr, ifp)) == NULL) { 1958 error = ENOBUFS; 1959 crit_exit(); 1960 break; 1961 } 1962 ++imo->imo_num_memberships; 1963 crit_exit(); 1964 break; 1965 1966 case IP_DROP_MEMBERSHIP: 1967 /* 1968 * Drop a multicast group membership. 1969 * Group must be a valid IP multicast address. 1970 */ 1971 error = soopt_to_kbuf(sopt, &mreq, sizeof mreq, sizeof mreq); 1972 if (error) 1973 break; 1974 1975 if (!IN_MULTICAST(ntohl(mreq.imr_multiaddr.s_addr))) { 1976 error = EINVAL; 1977 break; 1978 } 1979 1980 crit_enter(); 1981 /* 1982 * If an interface address was specified, get a pointer 1983 * to its ifnet structure. 1984 */ 1985 if (mreq.imr_interface.s_addr == INADDR_ANY) 1986 ifp = NULL; 1987 else { 1988 ifp = ip_multicast_if(&mreq.imr_interface, NULL); 1989 if (ifp == NULL) { 1990 error = EADDRNOTAVAIL; 1991 crit_exit(); 1992 break; 1993 } 1994 } 1995 /* 1996 * Find the membership in the membership array. 1997 */ 1998 for (i = 0; i < imo->imo_num_memberships; ++i) { 1999 if ((ifp == NULL || 2000 imo->imo_membership[i]->inm_ifp == ifp) && 2001 imo->imo_membership[i]->inm_addr.s_addr == 2002 mreq.imr_multiaddr.s_addr) 2003 break; 2004 } 2005 if (i == imo->imo_num_memberships) { 2006 error = EADDRNOTAVAIL; 2007 crit_exit(); 2008 break; 2009 } 2010 /* 2011 * Give up the multicast address record to which the 2012 * membership points. 2013 */ 2014 in_delmulti(imo->imo_membership[i]); 2015 /* 2016 * Remove the gap in the membership array. 2017 */ 2018 for (++i; i < imo->imo_num_memberships; ++i) 2019 imo->imo_membership[i-1] = imo->imo_membership[i]; 2020 --imo->imo_num_memberships; 2021 crit_exit(); 2022 break; 2023 2024 default: 2025 error = EOPNOTSUPP; 2026 break; 2027 } 2028 2029 /* 2030 * If all options have default values, no need to keep the mbuf. 2031 */ 2032 if (imo->imo_multicast_ifp == NULL && 2033 imo->imo_multicast_vif == -1 && 2034 imo->imo_multicast_ttl == IP_DEFAULT_MULTICAST_TTL && 2035 imo->imo_multicast_loop == IP_DEFAULT_MULTICAST_LOOP && 2036 imo->imo_num_memberships == 0) { 2037 kfree(*imop, M_IPMOPTS); 2038 *imop = NULL; 2039 } 2040 2041 return (error); 2042 } 2043 2044 /* 2045 * Return the IP multicast options in response to user getsockopt(). 2046 */ 2047 static int 2048 ip_getmoptions(struct sockopt *sopt, struct ip_moptions *imo) 2049 { 2050 struct in_addr addr; 2051 struct in_ifaddr *ia; 2052 int error, optval; 2053 u_char coptval; 2054 2055 error = 0; 2056 switch (sopt->sopt_name) { 2057 case IP_MULTICAST_VIF: 2058 if (imo != NULL) 2059 optval = imo->imo_multicast_vif; 2060 else 2061 optval = -1; 2062 soopt_from_kbuf(sopt, &optval, sizeof optval); 2063 break; 2064 2065 case IP_MULTICAST_IF: 2066 if (imo == NULL || imo->imo_multicast_ifp == NULL) 2067 addr.s_addr = INADDR_ANY; 2068 else if (imo->imo_multicast_addr.s_addr) { 2069 /* return the value user has set */ 2070 addr = imo->imo_multicast_addr; 2071 } else { 2072 ia = IFP_TO_IA(imo->imo_multicast_ifp); 2073 addr.s_addr = (ia == NULL) ? INADDR_ANY 2074 : IA_SIN(ia)->sin_addr.s_addr; 2075 } 2076 soopt_from_kbuf(sopt, &addr, sizeof addr); 2077 break; 2078 2079 case IP_MULTICAST_TTL: 2080 if (imo == NULL) 2081 optval = coptval = IP_DEFAULT_MULTICAST_TTL; 2082 else 2083 optval = coptval = imo->imo_multicast_ttl; 2084 if (sopt->sopt_valsize == 1) 2085 soopt_from_kbuf(sopt, &coptval, 1); 2086 else 2087 soopt_from_kbuf(sopt, &optval, sizeof optval); 2088 break; 2089 2090 case IP_MULTICAST_LOOP: 2091 if (imo == NULL) 2092 optval = coptval = IP_DEFAULT_MULTICAST_LOOP; 2093 else 2094 optval = coptval = imo->imo_multicast_loop; 2095 if (sopt->sopt_valsize == 1) 2096 soopt_from_kbuf(sopt, &coptval, 1); 2097 else 2098 soopt_from_kbuf(sopt, &optval, sizeof optval); 2099 break; 2100 2101 default: 2102 error = ENOPROTOOPT; 2103 break; 2104 } 2105 return (error); 2106 } 2107 2108 /* 2109 * Discard the IP multicast options. 2110 */ 2111 void 2112 ip_freemoptions(struct ip_moptions *imo) 2113 { 2114 int i; 2115 2116 if (imo != NULL) { 2117 for (i = 0; i < imo->imo_num_memberships; ++i) 2118 in_delmulti(imo->imo_membership[i]); 2119 kfree(imo, M_IPMOPTS); 2120 } 2121 } 2122 2123 /* 2124 * Routine called from ip_output() to loop back a copy of an IP multicast 2125 * packet to the input queue of a specified interface. Note that this 2126 * calls the output routine of the loopback "driver", but with an interface 2127 * pointer that might NOT be a loopback interface -- evil, but easier than 2128 * replicating that code here. 2129 */ 2130 static void 2131 ip_mloopback(struct ifnet *ifp, struct mbuf *m, struct sockaddr_in *dst, 2132 int hlen) 2133 { 2134 struct ip *ip; 2135 struct mbuf *copym; 2136 2137 copym = m_copypacket(m, MB_DONTWAIT); 2138 if (copym != NULL && (copym->m_flags & M_EXT || copym->m_len < hlen)) 2139 copym = m_pullup(copym, hlen); 2140 if (copym != NULL) { 2141 /* 2142 * if the checksum hasn't been computed, mark it as valid 2143 */ 2144 if (copym->m_pkthdr.csum_flags & CSUM_DELAY_DATA) { 2145 in_delayed_cksum(copym); 2146 copym->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA; 2147 copym->m_pkthdr.csum_flags |= 2148 CSUM_DATA_VALID | CSUM_PSEUDO_HDR; 2149 copym->m_pkthdr.csum_data = 0xffff; 2150 } 2151 /* 2152 * We don't bother to fragment if the IP length is greater 2153 * than the interface's MTU. Can this possibly matter? 2154 */ 2155 ip = mtod(copym, struct ip *); 2156 ip->ip_len = htons(ip->ip_len); 2157 ip->ip_off = htons(ip->ip_off); 2158 ip->ip_sum = 0; 2159 if (ip->ip_vhl == IP_VHL_BORING) { 2160 ip->ip_sum = in_cksum_hdr(ip); 2161 } else { 2162 ip->ip_sum = in_cksum(copym, hlen); 2163 } 2164 /* 2165 * NB: 2166 * It's not clear whether there are any lingering 2167 * reentrancy problems in other areas which might 2168 * be exposed by using ip_input directly (in 2169 * particular, everything which modifies the packet 2170 * in-place). Yet another option is using the 2171 * protosw directly to deliver the looped back 2172 * packet. For the moment, we'll err on the side 2173 * of safety by using if_simloop(). 2174 */ 2175 #if 1 /* XXX */ 2176 if (dst->sin_family != AF_INET) { 2177 kprintf("ip_mloopback: bad address family %d\n", 2178 dst->sin_family); 2179 dst->sin_family = AF_INET; 2180 } 2181 #endif 2182 get_mplock(); /* is if_simloop() mpsafe yet? */ 2183 if_simloop(ifp, copym, dst->sin_family, 0); 2184 rel_mplock(); 2185 } 2186 } 2187