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/thread2.h> 56 #include <sys/in_cksum.h> 57 #include <sys/lock.h> 58 59 #include <net/if.h> 60 #include <net/netisr.h> 61 #include <net/pfil.h> 62 #include <net/route.h> 63 64 #include <netinet/in.h> 65 #include <netinet/in_systm.h> 66 #include <netinet/ip.h> 67 #include <netinet/in_pcb.h> 68 #include <netinet/in_var.h> 69 #include <netinet/ip_var.h> 70 71 #include <netproto/mpls/mpls_var.h> 72 73 static MALLOC_DEFINE(M_IPMOPTS, "ip_moptions", "internet multicast options"); 74 75 #ifdef IPSEC 76 #include <netinet6/ipsec.h> 77 #include <netproto/key/key.h> 78 #ifdef IPSEC_DEBUG 79 #include <netproto/key/key_debug.h> 80 #else 81 #define KEYDEBUG(lev,arg) 82 #endif 83 #endif /*IPSEC*/ 84 85 #ifdef FAST_IPSEC 86 #include <netproto/ipsec/ipsec.h> 87 #include <netproto/ipsec/xform.h> 88 #include <netproto/ipsec/key.h> 89 #endif /*FAST_IPSEC*/ 90 91 #include <net/ipfw/ip_fw.h> 92 #include <net/dummynet/ip_dummynet.h> 93 94 #define print_ip(x, a, y) kprintf("%s %d.%d.%d.%d%s",\ 95 x, (ntohl(a.s_addr)>>24)&0xFF,\ 96 (ntohl(a.s_addr)>>16)&0xFF,\ 97 (ntohl(a.s_addr)>>8)&0xFF,\ 98 (ntohl(a.s_addr))&0xFF, y); 99 100 u_short ip_id; 101 102 #ifdef MBUF_STRESS_TEST 103 int mbuf_frag_size = 0; 104 SYSCTL_INT(_net_inet_ip, OID_AUTO, mbuf_frag_size, CTLFLAG_RW, 105 &mbuf_frag_size, 0, "Fragment outgoing mbufs to this size"); 106 #endif 107 108 static struct mbuf *ip_insertoptions(struct mbuf *, struct mbuf *, int *); 109 static struct ifnet *ip_multicast_if(struct in_addr *, int *); 110 static void ip_mloopback 111 (struct ifnet *, struct mbuf *, struct sockaddr_in *, int); 112 static int ip_getmoptions 113 (struct sockopt *, struct ip_moptions *); 114 static int ip_pcbopts(int, struct mbuf **, struct mbuf *); 115 static int ip_setmoptions 116 (struct sockopt *, struct ip_moptions **); 117 118 int ip_optcopy(struct ip *, struct ip *); 119 120 extern int route_assert_owner_access; 121 extern void db_print_backtrace(void); 122 123 extern struct protosw inetsw[]; 124 125 static int 126 ip_localforward(struct mbuf *m, const struct sockaddr_in *dst, int hlen) 127 { 128 struct in_ifaddr_container *iac; 129 130 /* 131 * We need to figure out if we have been forwarded to a local 132 * socket. If so, then we should somehow "loop back" to 133 * ip_input(), and get directed to the PCB as if we had received 134 * this packet. This is because it may be difficult to identify 135 * the packets you want to forward until they are being output 136 * and have selected an interface (e.g. locally initiated 137 * packets). If we used the loopback inteface, we would not be 138 * able to control what happens as the packet runs through 139 * ip_input() as it is done through a ISR. 140 */ 141 LIST_FOREACH(iac, INADDR_HASH(dst->sin_addr.s_addr), ia_hash) { 142 /* 143 * If the addr to forward to is one of ours, we pretend 144 * to be the destination for this packet. 145 */ 146 if (IA_SIN(iac->ia)->sin_addr.s_addr == dst->sin_addr.s_addr) 147 break; 148 } 149 if (iac != NULL) { 150 struct ip *ip; 151 152 if (m->m_pkthdr.rcvif == NULL) 153 m->m_pkthdr.rcvif = ifunit("lo0"); 154 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) { 155 m->m_pkthdr.csum_flags |= CSUM_DATA_VALID | 156 CSUM_PSEUDO_HDR; 157 m->m_pkthdr.csum_data = 0xffff; 158 } 159 m->m_pkthdr.csum_flags |= CSUM_IP_CHECKED | CSUM_IP_VALID; 160 161 /* 162 * Make sure that the IP header is in one mbuf, 163 * required by ip_input 164 */ 165 if (m->m_len < hlen) { 166 m = m_pullup(m, hlen); 167 if (m == NULL) { 168 /* The packet was freed; we are done */ 169 return 1; 170 } 171 } 172 ip = mtod(m, struct ip *); 173 174 ip->ip_len = htons(ip->ip_len); 175 ip->ip_off = htons(ip->ip_off); 176 ip_input(m); 177 178 return 1; /* The packet gets forwarded locally */ 179 } 180 return 0; 181 } 182 183 /* 184 * IP output. The packet in mbuf chain m contains a skeletal IP 185 * header (with len, off, ttl, proto, tos, src, dst). 186 * The mbuf chain containing the packet will be freed. 187 * The mbuf opt, if present, will not be freed. 188 */ 189 int 190 ip_output(struct mbuf *m0, struct mbuf *opt, struct route *ro, 191 int flags, struct ip_moptions *imo, struct inpcb *inp) 192 { 193 struct ip *ip; 194 struct ifnet *ifp = NULL; /* keep compiler happy */ 195 struct mbuf *m; 196 int hlen = sizeof(struct ip); 197 int len, error = 0; 198 struct sockaddr_in *dst = NULL; /* keep compiler happy */ 199 struct in_ifaddr *ia = NULL; 200 int isbroadcast, sw_csum; 201 struct in_addr pkt_dst; 202 struct route iproute; 203 struct m_tag *mtag; 204 #ifdef IPSEC 205 struct secpolicy *sp = NULL; 206 struct socket *so = inp ? inp->inp_socket : NULL; 207 #endif 208 #ifdef FAST_IPSEC 209 struct secpolicy *sp = NULL; 210 struct tdb_ident *tdbi; 211 #endif /* FAST_IPSEC */ 212 struct sockaddr_in *next_hop = NULL; 213 int src_was_INADDR_ANY = 0; /* as the name says... */ 214 215 m = m0; 216 M_ASSERTPKTHDR(m); 217 218 if (ro == NULL) { 219 ro = &iproute; 220 bzero(ro, sizeof *ro); 221 } else if (ro->ro_rt != NULL && ro->ro_rt->rt_cpuid != mycpuid) { 222 if (flags & IP_DEBUGROUTE) { 223 if (route_assert_owner_access) { 224 panic("ip_output: " 225 "rt rt_cpuid %d accessed on cpu %d\n", 226 ro->ro_rt->rt_cpuid, mycpuid); 227 } else { 228 kprintf("ip_output: " 229 "rt rt_cpuid %d accessed on cpu %d\n", 230 ro->ro_rt->rt_cpuid, mycpuid); 231 db_print_backtrace(); 232 } 233 } 234 235 /* 236 * XXX 237 * If the cached rtentry's owner CPU is not the current CPU, 238 * then don't touch the cached rtentry (remote free is too 239 * expensive in this context); just relocate the route. 240 */ 241 ro = &iproute; 242 bzero(ro, sizeof *ro); 243 } 244 245 if (m->m_pkthdr.fw_flags & IPFORWARD_MBUF_TAGGED) { 246 /* Next hop */ 247 mtag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL); 248 KKASSERT(mtag != NULL); 249 next_hop = m_tag_data(mtag); 250 } 251 252 if (m->m_pkthdr.fw_flags & DUMMYNET_MBUF_TAGGED) { 253 struct dn_pkt *dn_pkt; 254 255 /* Extract info from dummynet tag */ 256 mtag = m_tag_find(m, PACKET_TAG_DUMMYNET, NULL); 257 KKASSERT(mtag != NULL); 258 dn_pkt = m_tag_data(mtag); 259 260 /* 261 * The packet was already tagged, so part of the 262 * processing was already done, and we need to go down. 263 * Get the calculated parameters from the tag. 264 */ 265 ifp = dn_pkt->ifp; 266 267 KKASSERT(ro == &iproute); 268 *ro = dn_pkt->ro; /* structure copy */ 269 KKASSERT(ro->ro_rt == NULL || ro->ro_rt->rt_cpuid == mycpuid); 270 271 dst = dn_pkt->dn_dst; 272 if (dst == (struct sockaddr_in *)&(dn_pkt->ro.ro_dst)) { 273 /* If 'dst' points into dummynet tag, adjust it */ 274 dst = (struct sockaddr_in *)&(ro->ro_dst); 275 } 276 277 ip = mtod(m, struct ip *); 278 hlen = IP_VHL_HL(ip->ip_vhl) << 2 ; 279 if (ro->ro_rt) 280 ia = ifatoia(ro->ro_rt->rt_ifa); 281 goto sendit; 282 } 283 284 if (opt) { 285 len = 0; 286 m = ip_insertoptions(m, opt, &len); 287 if (len != 0) 288 hlen = len; 289 } 290 ip = mtod(m, struct ip *); 291 292 /* 293 * Fill in IP header. 294 */ 295 if (!(flags & (IP_FORWARDING|IP_RAWOUTPUT))) { 296 ip->ip_vhl = IP_MAKE_VHL(IPVERSION, hlen >> 2); 297 ip->ip_off &= IP_DF; 298 ip->ip_id = ip_newid(); 299 ipstat.ips_localout++; 300 } else { 301 hlen = IP_VHL_HL(ip->ip_vhl) << 2; 302 } 303 304 reroute: 305 pkt_dst = next_hop ? next_hop->sin_addr : ip->ip_dst; 306 307 #ifdef INVARIANTS 308 if (IN_MULTICAST(ntohl(pkt_dst.s_addr))) { 309 /* 310 * XXX 311 * Multicast is not MPSAFE yet. Caller must hold 312 * BGL when output a multicast IP packet. 313 */ 314 ASSERT_MP_LOCK_HELD(curthread); 315 } 316 #endif 317 318 dst = (struct sockaddr_in *)&ro->ro_dst; 319 /* 320 * If there is a cached route, 321 * check that it is to the same destination 322 * and is still up. If not, free it and try again. 323 * The address family should also be checked in case of sharing the 324 * cache with IPv6. 325 */ 326 if (ro->ro_rt && 327 (!(ro->ro_rt->rt_flags & RTF_UP) || 328 dst->sin_family != AF_INET || 329 dst->sin_addr.s_addr != pkt_dst.s_addr)) { 330 rtfree(ro->ro_rt); 331 ro->ro_rt = (struct rtentry *)NULL; 332 } 333 if (ro->ro_rt == NULL) { 334 bzero(dst, sizeof *dst); 335 dst->sin_family = AF_INET; 336 dst->sin_len = sizeof *dst; 337 dst->sin_addr = pkt_dst; 338 } 339 /* 340 * If routing to interface only, 341 * short circuit routing lookup. 342 */ 343 if (flags & IP_ROUTETOIF) { 344 if ((ia = ifatoia(ifa_ifwithdstaddr(sintosa(dst)))) == NULL && 345 (ia = ifatoia(ifa_ifwithnet(sintosa(dst)))) == NULL) { 346 ipstat.ips_noroute++; 347 error = ENETUNREACH; 348 goto bad; 349 } 350 ifp = ia->ia_ifp; 351 ip->ip_ttl = 1; 352 isbroadcast = in_broadcast(dst->sin_addr, ifp); 353 } else if (IN_MULTICAST(ntohl(pkt_dst.s_addr)) && 354 imo != NULL && imo->imo_multicast_ifp != NULL) { 355 /* 356 * Bypass the normal routing lookup for multicast 357 * packets if the interface is specified. 358 */ 359 ifp = imo->imo_multicast_ifp; 360 ia = IFP_TO_IA(ifp); 361 isbroadcast = 0; /* fool gcc */ 362 } else { 363 /* 364 * If this is the case, we probably don't want to allocate 365 * a protocol-cloned route since we didn't get one from the 366 * ULP. This lets TCP do its thing, while not burdening 367 * forwarding or ICMP with the overhead of cloning a route. 368 * Of course, we still want to do any cloning requested by 369 * the link layer, as this is probably required in all cases 370 * for correct operation (as it is for ARP). 371 */ 372 if (ro->ro_rt == NULL) 373 rtalloc_ign(ro, RTF_PRCLONING); 374 if (ro->ro_rt == NULL) { 375 ipstat.ips_noroute++; 376 error = EHOSTUNREACH; 377 goto bad; 378 } 379 ia = ifatoia(ro->ro_rt->rt_ifa); 380 ifp = ro->ro_rt->rt_ifp; 381 ro->ro_rt->rt_use++; 382 if (ro->ro_rt->rt_flags & RTF_GATEWAY) 383 dst = (struct sockaddr_in *)ro->ro_rt->rt_gateway; 384 if (ro->ro_rt->rt_flags & RTF_HOST) 385 isbroadcast = (ro->ro_rt->rt_flags & RTF_BROADCAST); 386 else 387 isbroadcast = in_broadcast(dst->sin_addr, ifp); 388 } 389 if (IN_MULTICAST(ntohl(pkt_dst.s_addr))) { 390 struct in_multi *inm; 391 392 m->m_flags |= M_MCAST; 393 /* 394 * IP destination address is multicast. Make sure "dst" 395 * still points to the address in "ro". (It may have been 396 * changed to point to a gateway address, above.) 397 */ 398 dst = (struct sockaddr_in *)&ro->ro_dst; 399 /* 400 * See if the caller provided any multicast options 401 */ 402 if (imo != NULL) { 403 ip->ip_ttl = imo->imo_multicast_ttl; 404 if (imo->imo_multicast_vif != -1) { 405 ip->ip_src.s_addr = 406 ip_mcast_src ? 407 ip_mcast_src(imo->imo_multicast_vif) : 408 INADDR_ANY; 409 } 410 } else { 411 ip->ip_ttl = IP_DEFAULT_MULTICAST_TTL; 412 } 413 /* 414 * Confirm that the outgoing interface supports multicast. 415 */ 416 if ((imo == NULL) || (imo->imo_multicast_vif == -1)) { 417 if (!(ifp->if_flags & IFF_MULTICAST)) { 418 ipstat.ips_noroute++; 419 error = ENETUNREACH; 420 goto bad; 421 } 422 } 423 /* 424 * If source address not specified yet, use address 425 * of outgoing interface. 426 */ 427 if (ip->ip_src.s_addr == INADDR_ANY) { 428 /* Interface may have no addresses. */ 429 if (ia != NULL) 430 ip->ip_src = IA_SIN(ia)->sin_addr; 431 } 432 433 IN_LOOKUP_MULTI(pkt_dst, ifp, inm); 434 if (inm != NULL && 435 (imo == NULL || imo->imo_multicast_loop)) { 436 /* 437 * If we belong to the destination multicast group 438 * on the outgoing interface, and the caller did not 439 * forbid loopback, loop back a copy. 440 */ 441 ip_mloopback(ifp, m, dst, hlen); 442 } else { 443 /* 444 * If we are acting as a multicast router, perform 445 * multicast forwarding as if the packet had just 446 * arrived on the interface to which we are about 447 * to send. The multicast forwarding function 448 * recursively calls this function, using the 449 * IP_FORWARDING flag to prevent infinite recursion. 450 * 451 * Multicasts that are looped back by ip_mloopback(), 452 * above, will be forwarded by the ip_input() routine, 453 * if necessary. 454 */ 455 if (ip_mrouter && !(flags & IP_FORWARDING)) { 456 /* 457 * If rsvp daemon is not running, do not 458 * set ip_moptions. This ensures that the packet 459 * is multicast and not just sent down one link 460 * as prescribed by rsvpd. 461 */ 462 if (!rsvp_on) 463 imo = NULL; 464 if (ip_mforward && 465 ip_mforward(ip, ifp, m, imo) != 0) { 466 m_freem(m); 467 goto done; 468 } 469 } 470 } 471 472 /* 473 * Multicasts with a time-to-live of zero may be looped- 474 * back, above, but must not be transmitted on a network. 475 * Also, multicasts addressed to the loopback interface 476 * are not sent -- the above call to ip_mloopback() will 477 * loop back a copy if this host actually belongs to the 478 * destination group on the loopback interface. 479 */ 480 if (ip->ip_ttl == 0 || ifp->if_flags & IFF_LOOPBACK) { 481 m_freem(m); 482 goto done; 483 } 484 485 goto sendit; 486 } else { 487 m->m_flags &= ~M_MCAST; 488 } 489 490 /* 491 * If the source address is not specified yet, use the address 492 * of the outoing interface. In case, keep note we did that, so 493 * if the the firewall changes the next-hop causing the output 494 * interface to change, we can fix that. 495 */ 496 if (ip->ip_src.s_addr == INADDR_ANY || src_was_INADDR_ANY) { 497 /* Interface may have no addresses. */ 498 if (ia != NULL) { 499 ip->ip_src = IA_SIN(ia)->sin_addr; 500 src_was_INADDR_ANY = 1; 501 } 502 } 503 504 #ifdef ALTQ 505 /* 506 * Disable packet drop hack. 507 * Packetdrop should be done by queueing. 508 */ 509 #else /* !ALTQ */ 510 /* 511 * Verify that we have any chance at all of being able to queue 512 * the packet or packet fragments 513 */ 514 if ((ifp->if_snd.ifq_len + ip->ip_len / ifp->if_mtu + 1) >= 515 ifp->if_snd.ifq_maxlen) { 516 error = ENOBUFS; 517 ipstat.ips_odropped++; 518 goto bad; 519 } 520 #endif /* !ALTQ */ 521 522 /* 523 * Look for broadcast address and 524 * verify user is allowed to send 525 * such a packet. 526 */ 527 if (isbroadcast) { 528 if (!(ifp->if_flags & IFF_BROADCAST)) { 529 error = EADDRNOTAVAIL; 530 goto bad; 531 } 532 if (!(flags & IP_ALLOWBROADCAST)) { 533 error = EACCES; 534 goto bad; 535 } 536 /* don't allow broadcast messages to be fragmented */ 537 if (ip->ip_len > ifp->if_mtu) { 538 error = EMSGSIZE; 539 goto bad; 540 } 541 m->m_flags |= M_BCAST; 542 } else { 543 m->m_flags &= ~M_BCAST; 544 } 545 546 sendit: 547 #ifdef IPSEC 548 /* get SP for this packet */ 549 if (so == NULL) 550 sp = ipsec4_getpolicybyaddr(m, IPSEC_DIR_OUTBOUND, flags, &error); 551 else 552 sp = ipsec4_getpolicybysock(m, IPSEC_DIR_OUTBOUND, so, &error); 553 554 if (sp == NULL) { 555 ipsecstat.out_inval++; 556 goto bad; 557 } 558 559 error = 0; 560 561 /* check policy */ 562 switch (sp->policy) { 563 case IPSEC_POLICY_DISCARD: 564 /* 565 * This packet is just discarded. 566 */ 567 ipsecstat.out_polvio++; 568 goto bad; 569 570 case IPSEC_POLICY_BYPASS: 571 case IPSEC_POLICY_NONE: 572 /* no need to do IPsec. */ 573 goto skip_ipsec; 574 575 case IPSEC_POLICY_IPSEC: 576 if (sp->req == NULL) { 577 /* acquire a policy */ 578 error = key_spdacquire(sp); 579 goto bad; 580 } 581 break; 582 583 case IPSEC_POLICY_ENTRUST: 584 default: 585 kprintf("ip_output: Invalid policy found. %d\n", sp->policy); 586 } 587 { 588 struct ipsec_output_state state; 589 bzero(&state, sizeof state); 590 state.m = m; 591 if (flags & IP_ROUTETOIF) { 592 state.ro = &iproute; 593 bzero(&iproute, sizeof iproute); 594 } else 595 state.ro = ro; 596 state.dst = (struct sockaddr *)dst; 597 598 ip->ip_sum = 0; 599 600 /* 601 * XXX 602 * delayed checksums are not currently compatible with IPsec 603 */ 604 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) { 605 in_delayed_cksum(m); 606 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA; 607 } 608 609 ip->ip_len = htons(ip->ip_len); 610 ip->ip_off = htons(ip->ip_off); 611 612 error = ipsec4_output(&state, sp, flags); 613 614 m = state.m; 615 if (flags & IP_ROUTETOIF) { 616 /* 617 * if we have tunnel mode SA, we may need to ignore 618 * IP_ROUTETOIF. 619 */ 620 if (state.ro != &iproute || state.ro->ro_rt != NULL) { 621 flags &= ~IP_ROUTETOIF; 622 ro = state.ro; 623 } 624 } else 625 ro = state.ro; 626 dst = (struct sockaddr_in *)state.dst; 627 if (error) { 628 /* mbuf is already reclaimed in ipsec4_output. */ 629 m0 = NULL; 630 switch (error) { 631 case EHOSTUNREACH: 632 case ENETUNREACH: 633 case EMSGSIZE: 634 case ENOBUFS: 635 case ENOMEM: 636 break; 637 default: 638 kprintf("ip4_output (ipsec): error code %d\n", error); 639 /*fall through*/ 640 case ENOENT: 641 /* don't show these error codes to the user */ 642 error = 0; 643 break; 644 } 645 goto bad; 646 } 647 } 648 649 /* be sure to update variables that are affected by ipsec4_output() */ 650 ip = mtod(m, struct ip *); 651 #ifdef _IP_VHL 652 hlen = IP_VHL_HL(ip->ip_vhl) << 2; 653 #else 654 hlen = ip->ip_hl << 2; 655 #endif 656 if (ro->ro_rt == NULL) { 657 if (!(flags & IP_ROUTETOIF)) { 658 kprintf("ip_output: " 659 "can't update route after IPsec processing\n"); 660 error = EHOSTUNREACH; /*XXX*/ 661 goto bad; 662 } 663 } else { 664 ia = ifatoia(ro->ro_rt->rt_ifa); 665 ifp = ro->ro_rt->rt_ifp; 666 } 667 668 /* make it flipped, again. */ 669 ip->ip_len = ntohs(ip->ip_len); 670 ip->ip_off = ntohs(ip->ip_off); 671 skip_ipsec: 672 #endif /*IPSEC*/ 673 #ifdef FAST_IPSEC 674 /* 675 * Check the security policy (SP) for the packet and, if 676 * required, do IPsec-related processing. There are two 677 * cases here; the first time a packet is sent through 678 * it will be untagged and handled by ipsec4_checkpolicy. 679 * If the packet is resubmitted to ip_output (e.g. after 680 * AH, ESP, etc. processing), there will be a tag to bypass 681 * the lookup and related policy checking. 682 */ 683 mtag = m_tag_find(m, PACKET_TAG_IPSEC_PENDING_TDB, NULL); 684 crit_enter(); 685 if (mtag != NULL) { 686 tdbi = (struct tdb_ident *)m_tag_data(mtag); 687 sp = ipsec_getpolicy(tdbi, IPSEC_DIR_OUTBOUND); 688 if (sp == NULL) 689 error = -EINVAL; /* force silent drop */ 690 m_tag_delete(m, mtag); 691 } else { 692 sp = ipsec4_checkpolicy(m, IPSEC_DIR_OUTBOUND, flags, 693 &error, inp); 694 } 695 /* 696 * There are four return cases: 697 * sp != NULL apply IPsec policy 698 * sp == NULL, error == 0 no IPsec handling needed 699 * sp == NULL, error == -EINVAL discard packet w/o error 700 * sp == NULL, error != 0 discard packet, report error 701 */ 702 if (sp != NULL) { 703 /* Loop detection, check if ipsec processing already done */ 704 KASSERT(sp->req != NULL, ("ip_output: no ipsec request")); 705 for (mtag = m_tag_first(m); mtag != NULL; 706 mtag = m_tag_next(m, mtag)) { 707 if (mtag->m_tag_cookie != MTAG_ABI_COMPAT) 708 continue; 709 if (mtag->m_tag_id != PACKET_TAG_IPSEC_OUT_DONE && 710 mtag->m_tag_id != PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED) 711 continue; 712 /* 713 * Check if policy has an SA associated with it. 714 * This can happen when an SP has yet to acquire 715 * an SA; e.g. on first reference. If it occurs, 716 * then we let ipsec4_process_packet do its thing. 717 */ 718 if (sp->req->sav == NULL) 719 break; 720 tdbi = (struct tdb_ident *)m_tag_data(mtag); 721 if (tdbi->spi == sp->req->sav->spi && 722 tdbi->proto == sp->req->sav->sah->saidx.proto && 723 bcmp(&tdbi->dst, &sp->req->sav->sah->saidx.dst, 724 sizeof(union sockaddr_union)) == 0) { 725 /* 726 * No IPsec processing is needed, free 727 * reference to SP. 728 * 729 * NB: null pointer to avoid free at 730 * done: below. 731 */ 732 KEY_FREESP(&sp), sp = NULL; 733 crit_exit(); 734 goto spd_done; 735 } 736 } 737 738 /* 739 * Do delayed checksums now because we send before 740 * this is done in the normal processing path. 741 */ 742 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) { 743 in_delayed_cksum(m); 744 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA; 745 } 746 747 ip->ip_len = htons(ip->ip_len); 748 ip->ip_off = htons(ip->ip_off); 749 750 /* NB: callee frees mbuf */ 751 error = ipsec4_process_packet(m, sp->req, flags, 0); 752 /* 753 * Preserve KAME behaviour: ENOENT can be returned 754 * when an SA acquire is in progress. Don't propagate 755 * this to user-level; it confuses applications. 756 * 757 * XXX this will go away when the SADB is redone. 758 */ 759 if (error == ENOENT) 760 error = 0; 761 crit_exit(); 762 goto done; 763 } else { 764 crit_exit(); 765 766 if (error != 0) { 767 /* 768 * Hack: -EINVAL is used to signal that a packet 769 * should be silently discarded. This is typically 770 * because we asked key management for an SA and 771 * it was delayed (e.g. kicked up to IKE). 772 */ 773 if (error == -EINVAL) 774 error = 0; 775 goto bad; 776 } else { 777 /* No IPsec processing for this packet. */ 778 } 779 #ifdef notyet 780 /* 781 * If deferred crypto processing is needed, check that 782 * the interface supports it. 783 */ 784 mtag = m_tag_find(m, PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED, NULL); 785 if (mtag != NULL && !(ifp->if_capenable & IFCAP_IPSEC)) { 786 /* notify IPsec to do its own crypto */ 787 ipsp_skipcrypto_unmark((struct tdb_ident *)m_tag_data(mtag)); 788 error = EHOSTUNREACH; 789 goto bad; 790 } 791 #endif 792 } 793 spd_done: 794 #endif /* FAST_IPSEC */ 795 796 /* We are already being fwd'd from a firewall. */ 797 if (next_hop != NULL) 798 goto pass; 799 800 /* No pfil hooks */ 801 if (!pfil_has_hooks(&inet_pfil_hook)) { 802 if (m->m_pkthdr.fw_flags & DUMMYNET_MBUF_TAGGED) { 803 /* 804 * Strip dummynet tags from stranded packets 805 */ 806 mtag = m_tag_find(m, PACKET_TAG_DUMMYNET, NULL); 807 KKASSERT(mtag != NULL); 808 m_tag_delete(m, mtag); 809 m->m_pkthdr.fw_flags &= ~DUMMYNET_MBUF_TAGGED; 810 } 811 goto pass; 812 } 813 814 /* 815 * IpHack's section. 816 * - Xlate: translate packet's addr/port (NAT). 817 * - Firewall: deny/allow/etc. 818 * - Wrap: fake packet's addr/port <unimpl.> 819 * - Encapsulate: put it in another IP and send out. <unimp.> 820 */ 821 822 /* 823 * Run through list of hooks for output packets. 824 */ 825 error = pfil_run_hooks(&inet_pfil_hook, &m, ifp, PFIL_OUT); 826 if (error != 0 || m == NULL) 827 goto done; 828 ip = mtod(m, struct ip *); 829 830 if (m->m_pkthdr.fw_flags & IPFORWARD_MBUF_TAGGED) { 831 /* 832 * Check dst to make sure it is directly reachable on the 833 * interface we previously thought it was. 834 * If it isn't (which may be likely in some situations) we have 835 * to re-route it (ie, find a route for the next-hop and the 836 * associated interface) and set them here. This is nested 837 * forwarding which in most cases is undesirable, except where 838 * such control is nigh impossible. So we do it here. 839 * And I'm babbling. 840 */ 841 mtag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL); 842 KKASSERT(mtag != NULL); 843 next_hop = m_tag_data(mtag); 844 845 /* 846 * Try local forwarding first 847 */ 848 if (ip_localforward(m, next_hop, hlen)) 849 goto done; 850 851 /* 852 * Relocate the route based on next_hop. 853 * If the current route is inp's cache, keep it untouched. 854 */ 855 if (ro == &iproute && ro->ro_rt != NULL) { 856 RTFREE(ro->ro_rt); 857 ro->ro_rt = NULL; 858 } 859 ro = &iproute; 860 bzero(ro, sizeof *ro); 861 862 /* 863 * Forwarding to broadcast address is not allowed. 864 * XXX Should we follow IP_ROUTETOIF? 865 */ 866 flags &= ~(IP_ALLOWBROADCAST | IP_ROUTETOIF); 867 868 /* We are doing forwarding now */ 869 flags |= IP_FORWARDING; 870 871 goto reroute; 872 } 873 874 if (m->m_pkthdr.fw_flags & DUMMYNET_MBUF_TAGGED) { 875 struct dn_pkt *dn_pkt; 876 877 mtag = m_tag_find(m, PACKET_TAG_DUMMYNET, NULL); 878 KKASSERT(mtag != NULL); 879 dn_pkt = m_tag_data(mtag); 880 881 /* 882 * Under certain cases it is not possible to recalculate 883 * 'ro' and 'dst', let alone 'flags', so just save them in 884 * dummynet tag and avoid the possible wrong reculcalation 885 * when we come back to ip_output() again. 886 * 887 * All other parameters have been already used and so they 888 * are not needed anymore. 889 * XXX if the ifp is deleted while a pkt is in dummynet, 890 * we are in trouble! (TODO use ifnet_detach_event) 891 * 892 * We need to copy *ro because for ICMP pkts (and maybe 893 * others) the caller passed a pointer into the stack; 894 * dst might also be a pointer into *ro so it needs to 895 * be updated. 896 */ 897 dn_pkt->ro = *ro; 898 if (ro->ro_rt) 899 ro->ro_rt->rt_refcnt++; 900 if (dst == (struct sockaddr_in *)&ro->ro_dst) { 901 /* 'dst' points into 'ro' */ 902 dst = (struct sockaddr_in *)&(dn_pkt->ro.ro_dst); 903 } 904 dn_pkt->dn_dst = dst; 905 dn_pkt->flags = flags; 906 907 ip_dn_queue(m); 908 goto done; 909 } 910 pass: 911 /* 127/8 must not appear on wire - RFC1122. */ 912 if ((ntohl(ip->ip_dst.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET || 913 (ntohl(ip->ip_src.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET) { 914 if (!(ifp->if_flags & IFF_LOOPBACK)) { 915 ipstat.ips_badaddr++; 916 error = EADDRNOTAVAIL; 917 goto bad; 918 } 919 } 920 921 m->m_pkthdr.csum_flags |= CSUM_IP; 922 sw_csum = m->m_pkthdr.csum_flags & ~ifp->if_hwassist; 923 if (sw_csum & CSUM_DELAY_DATA) { 924 in_delayed_cksum(m); 925 sw_csum &= ~CSUM_DELAY_DATA; 926 } 927 m->m_pkthdr.csum_flags &= ifp->if_hwassist; 928 929 /* 930 * If small enough for interface, or the interface will take 931 * care of the fragmentation for us, can just send directly. 932 */ 933 if (ip->ip_len <= ifp->if_mtu || ((ifp->if_hwassist & CSUM_FRAGMENT) && 934 !(ip->ip_off & IP_DF))) { 935 ip->ip_len = htons(ip->ip_len); 936 ip->ip_off = htons(ip->ip_off); 937 ip->ip_sum = 0; 938 if (sw_csum & CSUM_DELAY_IP) { 939 if (ip->ip_vhl == IP_VHL_BORING) 940 ip->ip_sum = in_cksum_hdr(ip); 941 else 942 ip->ip_sum = in_cksum(m, hlen); 943 } 944 945 /* Record statistics for this interface address. */ 946 if (!(flags & IP_FORWARDING) && ia) { 947 ia->ia_ifa.if_opackets++; 948 ia->ia_ifa.if_obytes += m->m_pkthdr.len; 949 } 950 951 #ifdef IPSEC 952 /* clean ipsec history once it goes out of the node */ 953 ipsec_delaux(m); 954 #endif 955 956 #ifdef MBUF_STRESS_TEST 957 if (mbuf_frag_size && m->m_pkthdr.len > mbuf_frag_size) { 958 struct mbuf *m1, *m2; 959 int length, tmp; 960 961 tmp = length = m->m_pkthdr.len; 962 963 while ((length -= mbuf_frag_size) >= 1) { 964 m1 = m_split(m, length, MB_DONTWAIT); 965 if (m1 == NULL) 966 break; 967 m2 = m; 968 while (m2->m_next != NULL) 969 m2 = m2->m_next; 970 m2->m_next = m1; 971 } 972 m->m_pkthdr.len = tmp; 973 } 974 #endif 975 976 #ifdef MPLS 977 if (!mpls_output_process(m, ro->ro_rt)) 978 goto done; 979 #endif 980 error = ifp->if_output(ifp, m, (struct sockaddr *)dst, 981 ro->ro_rt); 982 goto done; 983 } 984 985 if (ip->ip_off & IP_DF) { 986 error = EMSGSIZE; 987 /* 988 * This case can happen if the user changed the MTU 989 * of an interface after enabling IP on it. Because 990 * most netifs don't keep track of routes pointing to 991 * them, there is no way for one to update all its 992 * routes when the MTU is changed. 993 */ 994 if ((ro->ro_rt->rt_flags & (RTF_UP | RTF_HOST)) && 995 !(ro->ro_rt->rt_rmx.rmx_locks & RTV_MTU) && 996 (ro->ro_rt->rt_rmx.rmx_mtu > ifp->if_mtu)) { 997 ro->ro_rt->rt_rmx.rmx_mtu = ifp->if_mtu; 998 } 999 ipstat.ips_cantfrag++; 1000 goto bad; 1001 } 1002 1003 /* 1004 * Too large for interface; fragment if possible. If successful, 1005 * on return, m will point to a list of packets to be sent. 1006 */ 1007 error = ip_fragment(ip, &m, ifp->if_mtu, ifp->if_hwassist, sw_csum); 1008 if (error) 1009 goto bad; 1010 for (; m; m = m0) { 1011 m0 = m->m_nextpkt; 1012 m->m_nextpkt = NULL; 1013 #ifdef IPSEC 1014 /* clean ipsec history once it goes out of the node */ 1015 ipsec_delaux(m); 1016 #endif 1017 if (error == 0) { 1018 /* Record statistics for this interface address. */ 1019 if (ia != NULL) { 1020 ia->ia_ifa.if_opackets++; 1021 ia->ia_ifa.if_obytes += m->m_pkthdr.len; 1022 } 1023 #ifdef MPLS 1024 if (!mpls_output_process(m, ro->ro_rt)) 1025 continue; 1026 #endif 1027 error = ifp->if_output(ifp, m, (struct sockaddr *)dst, 1028 ro->ro_rt); 1029 } else { 1030 m_freem(m); 1031 } 1032 } 1033 1034 if (error == 0) 1035 ipstat.ips_fragmented++; 1036 1037 done: 1038 if (ro == &iproute && ro->ro_rt != NULL) { 1039 RTFREE(ro->ro_rt); 1040 ro->ro_rt = NULL; 1041 } 1042 #ifdef IPSEC 1043 if (sp != NULL) { 1044 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 1045 kprintf("DP ip_output call free SP:%p\n", sp)); 1046 key_freesp(sp); 1047 } 1048 #endif 1049 #ifdef FAST_IPSEC 1050 if (sp != NULL) 1051 KEY_FREESP(&sp); 1052 #endif 1053 return (error); 1054 bad: 1055 m_freem(m); 1056 goto done; 1057 } 1058 1059 /* 1060 * Create a chain of fragments which fit the given mtu. m_frag points to the 1061 * mbuf to be fragmented; on return it points to the chain with the fragments. 1062 * Return 0 if no error. If error, m_frag may contain a partially built 1063 * chain of fragments that should be freed by the caller. 1064 * 1065 * if_hwassist_flags is the hw offload capabilities (see if_data.ifi_hwassist) 1066 * sw_csum contains the delayed checksums flags (e.g., CSUM_DELAY_IP). 1067 */ 1068 int 1069 ip_fragment(struct ip *ip, struct mbuf **m_frag, int mtu, 1070 u_long if_hwassist_flags, int sw_csum) 1071 { 1072 int error = 0; 1073 int hlen = IP_VHL_HL(ip->ip_vhl) << 2; 1074 int len = (mtu - hlen) & ~7; /* size of payload in each fragment */ 1075 int off; 1076 struct mbuf *m0 = *m_frag; /* the original packet */ 1077 int firstlen; 1078 struct mbuf **mnext; 1079 int nfrags; 1080 1081 if (ip->ip_off & IP_DF) { /* Fragmentation not allowed */ 1082 ipstat.ips_cantfrag++; 1083 return EMSGSIZE; 1084 } 1085 1086 /* 1087 * Must be able to put at least 8 bytes per fragment. 1088 */ 1089 if (len < 8) 1090 return EMSGSIZE; 1091 1092 /* 1093 * If the interface will not calculate checksums on 1094 * fragmented packets, then do it here. 1095 */ 1096 if ((m0->m_pkthdr.csum_flags & CSUM_DELAY_DATA) && 1097 !(if_hwassist_flags & CSUM_IP_FRAGS)) { 1098 in_delayed_cksum(m0); 1099 m0->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA; 1100 } 1101 1102 if (len > PAGE_SIZE) { 1103 /* 1104 * Fragment large datagrams such that each segment 1105 * contains a multiple of PAGE_SIZE amount of data, 1106 * plus headers. This enables a receiver to perform 1107 * page-flipping zero-copy optimizations. 1108 * 1109 * XXX When does this help given that sender and receiver 1110 * could have different page sizes, and also mtu could 1111 * be less than the receiver's page size ? 1112 */ 1113 int newlen; 1114 struct mbuf *m; 1115 1116 for (m = m0, off = 0; m && (off+m->m_len) <= mtu; m = m->m_next) 1117 off += m->m_len; 1118 1119 /* 1120 * firstlen (off - hlen) must be aligned on an 1121 * 8-byte boundary 1122 */ 1123 if (off < hlen) 1124 goto smart_frag_failure; 1125 off = ((off - hlen) & ~7) + hlen; 1126 newlen = (~PAGE_MASK) & mtu; 1127 if ((newlen + sizeof(struct ip)) > mtu) { 1128 /* we failed, go back the default */ 1129 smart_frag_failure: 1130 newlen = len; 1131 off = hlen + len; 1132 } 1133 len = newlen; 1134 1135 } else { 1136 off = hlen + len; 1137 } 1138 1139 firstlen = off - hlen; 1140 mnext = &m0->m_nextpkt; /* pointer to next packet */ 1141 1142 /* 1143 * Loop through length of segment after first fragment, 1144 * make new header and copy data of each part and link onto chain. 1145 * Here, m0 is the original packet, m is the fragment being created. 1146 * The fragments are linked off the m_nextpkt of the original 1147 * packet, which after processing serves as the first fragment. 1148 */ 1149 for (nfrags = 1; off < ip->ip_len; off += len, nfrags++) { 1150 struct ip *mhip; /* ip header on the fragment */ 1151 struct mbuf *m; 1152 int mhlen = sizeof(struct ip); 1153 1154 MGETHDR(m, MB_DONTWAIT, MT_HEADER); 1155 if (m == NULL) { 1156 error = ENOBUFS; 1157 ipstat.ips_odropped++; 1158 goto done; 1159 } 1160 m->m_flags |= (m0->m_flags & M_MCAST) | M_FRAG; 1161 /* 1162 * In the first mbuf, leave room for the link header, then 1163 * copy the original IP header including options. The payload 1164 * goes into an additional mbuf chain returned by m_copy(). 1165 */ 1166 m->m_data += max_linkhdr; 1167 mhip = mtod(m, struct ip *); 1168 *mhip = *ip; 1169 if (hlen > sizeof(struct ip)) { 1170 mhlen = ip_optcopy(ip, mhip) + sizeof(struct ip); 1171 mhip->ip_vhl = IP_MAKE_VHL(IPVERSION, mhlen >> 2); 1172 } 1173 m->m_len = mhlen; 1174 /* XXX do we need to add ip->ip_off below ? */ 1175 mhip->ip_off = ((off - hlen) >> 3) + ip->ip_off; 1176 if (off + len >= ip->ip_len) { /* last fragment */ 1177 len = ip->ip_len - off; 1178 m->m_flags |= M_LASTFRAG; 1179 } else 1180 mhip->ip_off |= IP_MF; 1181 mhip->ip_len = htons((u_short)(len + mhlen)); 1182 m->m_next = m_copy(m0, off, len); 1183 if (m->m_next == NULL) { /* copy failed */ 1184 m_free(m); 1185 error = ENOBUFS; /* ??? */ 1186 ipstat.ips_odropped++; 1187 goto done; 1188 } 1189 m->m_pkthdr.len = mhlen + len; 1190 m->m_pkthdr.rcvif = (struct ifnet *)NULL; 1191 m->m_pkthdr.csum_flags = m0->m_pkthdr.csum_flags; 1192 mhip->ip_off = htons(mhip->ip_off); 1193 mhip->ip_sum = 0; 1194 if (sw_csum & CSUM_DELAY_IP) 1195 mhip->ip_sum = in_cksum(m, mhlen); 1196 *mnext = m; 1197 mnext = &m->m_nextpkt; 1198 } 1199 ipstat.ips_ofragments += nfrags; 1200 1201 /* set first marker for fragment chain */ 1202 m0->m_flags |= M_FIRSTFRAG | M_FRAG; 1203 m0->m_pkthdr.csum_data = nfrags; 1204 1205 /* 1206 * Update first fragment by trimming what's been copied out 1207 * and updating header. 1208 */ 1209 m_adj(m0, hlen + firstlen - ip->ip_len); 1210 m0->m_pkthdr.len = hlen + firstlen; 1211 ip->ip_len = htons((u_short)m0->m_pkthdr.len); 1212 ip->ip_off |= IP_MF; 1213 ip->ip_off = htons(ip->ip_off); 1214 ip->ip_sum = 0; 1215 if (sw_csum & CSUM_DELAY_IP) 1216 ip->ip_sum = in_cksum(m0, hlen); 1217 1218 done: 1219 *m_frag = m0; 1220 return error; 1221 } 1222 1223 void 1224 in_delayed_cksum(struct mbuf *m) 1225 { 1226 struct ip *ip; 1227 u_short csum, offset; 1228 1229 ip = mtod(m, struct ip *); 1230 offset = IP_VHL_HL(ip->ip_vhl) << 2 ; 1231 csum = in_cksum_skip(m, ip->ip_len, offset); 1232 if (m->m_pkthdr.csum_flags & CSUM_UDP && csum == 0) 1233 csum = 0xffff; 1234 offset += m->m_pkthdr.csum_data; /* checksum offset */ 1235 1236 if (offset + sizeof(u_short) > m->m_len) { 1237 kprintf("delayed m_pullup, m->len: %d off: %d p: %d\n", 1238 m->m_len, offset, ip->ip_p); 1239 /* 1240 * XXX 1241 * this shouldn't happen, but if it does, the 1242 * correct behavior may be to insert the checksum 1243 * in the existing chain instead of rearranging it. 1244 */ 1245 m = m_pullup(m, offset + sizeof(u_short)); 1246 } 1247 *(u_short *)(m->m_data + offset) = csum; 1248 } 1249 1250 /* 1251 * Insert IP options into preformed packet. 1252 * Adjust IP destination as required for IP source routing, 1253 * as indicated by a non-zero in_addr at the start of the options. 1254 * 1255 * XXX This routine assumes that the packet has no options in place. 1256 */ 1257 static struct mbuf * 1258 ip_insertoptions(struct mbuf *m, struct mbuf *opt, int *phlen) 1259 { 1260 struct ipoption *p = mtod(opt, struct ipoption *); 1261 struct mbuf *n; 1262 struct ip *ip = mtod(m, struct ip *); 1263 unsigned optlen; 1264 1265 optlen = opt->m_len - sizeof p->ipopt_dst; 1266 if (optlen + (u_short)ip->ip_len > IP_MAXPACKET) { 1267 *phlen = 0; 1268 return (m); /* XXX should fail */ 1269 } 1270 if (p->ipopt_dst.s_addr) 1271 ip->ip_dst = p->ipopt_dst; 1272 if (m->m_flags & M_EXT || m->m_data - optlen < m->m_pktdat) { 1273 MGETHDR(n, MB_DONTWAIT, MT_HEADER); 1274 if (n == NULL) { 1275 *phlen = 0; 1276 return (m); 1277 } 1278 n->m_pkthdr.rcvif = (struct ifnet *)NULL; 1279 n->m_pkthdr.len = m->m_pkthdr.len + optlen; 1280 m->m_len -= sizeof(struct ip); 1281 m->m_data += sizeof(struct ip); 1282 n->m_next = m; 1283 m = n; 1284 m->m_len = optlen + sizeof(struct ip); 1285 m->m_data += max_linkhdr; 1286 memcpy(mtod(m, void *), ip, sizeof(struct ip)); 1287 } else { 1288 m->m_data -= optlen; 1289 m->m_len += optlen; 1290 m->m_pkthdr.len += optlen; 1291 ovbcopy(ip, mtod(m, caddr_t), sizeof(struct ip)); 1292 } 1293 ip = mtod(m, struct ip *); 1294 bcopy(p->ipopt_list, ip + 1, optlen); 1295 *phlen = sizeof(struct ip) + optlen; 1296 ip->ip_vhl = IP_MAKE_VHL(IPVERSION, *phlen >> 2); 1297 ip->ip_len += optlen; 1298 return (m); 1299 } 1300 1301 /* 1302 * Copy options from ip to jp, 1303 * omitting those not copied during fragmentation. 1304 */ 1305 int 1306 ip_optcopy(struct ip *ip, struct ip *jp) 1307 { 1308 u_char *cp, *dp; 1309 int opt, optlen, cnt; 1310 1311 cp = (u_char *)(ip + 1); 1312 dp = (u_char *)(jp + 1); 1313 cnt = (IP_VHL_HL(ip->ip_vhl) << 2) - sizeof(struct ip); 1314 for (; cnt > 0; cnt -= optlen, cp += optlen) { 1315 opt = cp[0]; 1316 if (opt == IPOPT_EOL) 1317 break; 1318 if (opt == IPOPT_NOP) { 1319 /* Preserve for IP mcast tunnel's LSRR alignment. */ 1320 *dp++ = IPOPT_NOP; 1321 optlen = 1; 1322 continue; 1323 } 1324 1325 KASSERT(cnt >= IPOPT_OLEN + sizeof *cp, 1326 ("ip_optcopy: malformed ipv4 option")); 1327 optlen = cp[IPOPT_OLEN]; 1328 KASSERT(optlen >= IPOPT_OLEN + sizeof *cp && optlen <= cnt, 1329 ("ip_optcopy: malformed ipv4 option")); 1330 1331 /* bogus lengths should have been caught by ip_dooptions */ 1332 if (optlen > cnt) 1333 optlen = cnt; 1334 if (IPOPT_COPIED(opt)) { 1335 bcopy(cp, dp, optlen); 1336 dp += optlen; 1337 } 1338 } 1339 for (optlen = dp - (u_char *)(jp+1); optlen & 0x3; optlen++) 1340 *dp++ = IPOPT_EOL; 1341 return (optlen); 1342 } 1343 1344 /* 1345 * IP socket option processing. 1346 */ 1347 int 1348 ip_ctloutput(struct socket *so, struct sockopt *sopt) 1349 { 1350 struct inpcb *inp = so->so_pcb; 1351 int error, optval; 1352 1353 error = optval = 0; 1354 if (sopt->sopt_level != IPPROTO_IP) { 1355 return (EINVAL); 1356 } 1357 1358 switch (sopt->sopt_dir) { 1359 case SOPT_SET: 1360 switch (sopt->sopt_name) { 1361 case IP_OPTIONS: 1362 #ifdef notyet 1363 case IP_RETOPTS: 1364 #endif 1365 { 1366 struct mbuf *m; 1367 if (sopt->sopt_valsize > MLEN) { 1368 error = EMSGSIZE; 1369 break; 1370 } 1371 MGET(m, sopt->sopt_td ? MB_WAIT : MB_DONTWAIT, MT_HEADER); 1372 if (m == NULL) { 1373 error = ENOBUFS; 1374 break; 1375 } 1376 m->m_len = sopt->sopt_valsize; 1377 error = soopt_to_kbuf(sopt, mtod(m, void *), m->m_len, 1378 m->m_len); 1379 return (ip_pcbopts(sopt->sopt_name, &inp->inp_options, 1380 m)); 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 return (error); 1618 } 1619 1620 /* 1621 * Set up IP options in pcb for insertion in output packets. 1622 * Store in mbuf with pointer in pcbopt, adding pseudo-option 1623 * with destination address if source routed. 1624 */ 1625 static int 1626 ip_pcbopts(int optname, struct mbuf **pcbopt, struct mbuf *m) 1627 { 1628 int cnt, optlen; 1629 u_char *cp; 1630 u_char opt; 1631 1632 /* turn off any old options */ 1633 if (*pcbopt) 1634 m_free(*pcbopt); 1635 *pcbopt = 0; 1636 if (m == NULL || m->m_len == 0) { 1637 /* 1638 * Only turning off any previous options. 1639 */ 1640 if (m != NULL) 1641 m_free(m); 1642 return (0); 1643 } 1644 1645 if (m->m_len % sizeof(int32_t)) 1646 goto bad; 1647 /* 1648 * IP first-hop destination address will be stored before 1649 * actual options; move other options back 1650 * and clear it when none present. 1651 */ 1652 if (m->m_data + m->m_len + sizeof(struct in_addr) >= &m->m_dat[MLEN]) 1653 goto bad; 1654 cnt = m->m_len; 1655 m->m_len += sizeof(struct in_addr); 1656 cp = mtod(m, u_char *) + sizeof(struct in_addr); 1657 ovbcopy(mtod(m, caddr_t), cp, cnt); 1658 bzero(mtod(m, caddr_t), sizeof(struct in_addr)); 1659 1660 for (; cnt > 0; cnt -= optlen, cp += optlen) { 1661 opt = cp[IPOPT_OPTVAL]; 1662 if (opt == IPOPT_EOL) 1663 break; 1664 if (opt == IPOPT_NOP) 1665 optlen = 1; 1666 else { 1667 if (cnt < IPOPT_OLEN + sizeof *cp) 1668 goto bad; 1669 optlen = cp[IPOPT_OLEN]; 1670 if (optlen < IPOPT_OLEN + sizeof *cp || optlen > cnt) 1671 goto bad; 1672 } 1673 switch (opt) { 1674 1675 default: 1676 break; 1677 1678 case IPOPT_LSRR: 1679 case IPOPT_SSRR: 1680 /* 1681 * user process specifies route as: 1682 * ->A->B->C->D 1683 * D must be our final destination (but we can't 1684 * check that since we may not have connected yet). 1685 * A is first hop destination, which doesn't appear in 1686 * actual IP option, but is stored before the options. 1687 */ 1688 if (optlen < IPOPT_MINOFF - 1 + sizeof(struct in_addr)) 1689 goto bad; 1690 m->m_len -= sizeof(struct in_addr); 1691 cnt -= sizeof(struct in_addr); 1692 optlen -= sizeof(struct in_addr); 1693 cp[IPOPT_OLEN] = optlen; 1694 /* 1695 * Move first hop before start of options. 1696 */ 1697 bcopy(&cp[IPOPT_OFFSET+1], mtod(m, caddr_t), 1698 sizeof(struct in_addr)); 1699 /* 1700 * Then copy rest of options back 1701 * to close up the deleted entry. 1702 */ 1703 ovbcopy(&cp[IPOPT_OFFSET+1] + sizeof(struct in_addr), 1704 &cp[IPOPT_OFFSET+1], 1705 cnt - (IPOPT_MINOFF - 1)); 1706 break; 1707 } 1708 } 1709 if (m->m_len > MAX_IPOPTLEN + sizeof(struct in_addr)) 1710 goto bad; 1711 *pcbopt = m; 1712 return (0); 1713 1714 bad: 1715 m_free(m); 1716 return (EINVAL); 1717 } 1718 1719 /* 1720 * XXX 1721 * The whole multicast option thing needs to be re-thought. 1722 * Several of these options are equally applicable to non-multicast 1723 * transmission, and one (IP_MULTICAST_TTL) totally duplicates a 1724 * standard option (IP_TTL). 1725 */ 1726 1727 /* 1728 * following RFC1724 section 3.3, 0.0.0.0/8 is interpreted as interface index. 1729 */ 1730 static struct ifnet * 1731 ip_multicast_if(struct in_addr *a, int *ifindexp) 1732 { 1733 int ifindex; 1734 struct ifnet *ifp; 1735 1736 if (ifindexp) 1737 *ifindexp = 0; 1738 if (ntohl(a->s_addr) >> 24 == 0) { 1739 ifindex = ntohl(a->s_addr) & 0xffffff; 1740 if (ifindex < 0 || if_index < ifindex) 1741 return NULL; 1742 ifp = ifindex2ifnet[ifindex]; 1743 if (ifindexp) 1744 *ifindexp = ifindex; 1745 } else { 1746 ifp = INADDR_TO_IFP(a); 1747 } 1748 return ifp; 1749 } 1750 1751 /* 1752 * Set the IP multicast options in response to user setsockopt(). 1753 */ 1754 static int 1755 ip_setmoptions(struct sockopt *sopt, struct ip_moptions **imop) 1756 { 1757 int error = 0; 1758 int i; 1759 struct in_addr addr; 1760 struct ip_mreq mreq; 1761 struct ifnet *ifp; 1762 struct ip_moptions *imo = *imop; 1763 int ifindex; 1764 1765 if (imo == NULL) { 1766 /* 1767 * No multicast option buffer attached to the pcb; 1768 * allocate one and initialize to default values. 1769 */ 1770 imo = kmalloc(sizeof *imo, M_IPMOPTS, M_WAITOK); 1771 1772 *imop = imo; 1773 imo->imo_multicast_ifp = NULL; 1774 imo->imo_multicast_addr.s_addr = INADDR_ANY; 1775 imo->imo_multicast_vif = -1; 1776 imo->imo_multicast_ttl = IP_DEFAULT_MULTICAST_TTL; 1777 imo->imo_multicast_loop = IP_DEFAULT_MULTICAST_LOOP; 1778 imo->imo_num_memberships = 0; 1779 } 1780 switch (sopt->sopt_name) { 1781 /* store an index number for the vif you wanna use in the send */ 1782 case IP_MULTICAST_VIF: 1783 if (legal_vif_num == 0) { 1784 error = EOPNOTSUPP; 1785 break; 1786 } 1787 error = soopt_to_kbuf(sopt, &i, sizeof i, sizeof i); 1788 if (error) 1789 break; 1790 if (!legal_vif_num(i) && (i != -1)) { 1791 error = EINVAL; 1792 break; 1793 } 1794 imo->imo_multicast_vif = i; 1795 break; 1796 1797 case IP_MULTICAST_IF: 1798 /* 1799 * Select the interface for outgoing multicast packets. 1800 */ 1801 error = soopt_to_kbuf(sopt, &addr, sizeof addr, sizeof addr); 1802 if (error) 1803 break; 1804 1805 /* 1806 * INADDR_ANY is used to remove a previous selection. 1807 * When no interface is selected, a default one is 1808 * chosen every time a multicast packet is sent. 1809 */ 1810 if (addr.s_addr == INADDR_ANY) { 1811 imo->imo_multicast_ifp = NULL; 1812 break; 1813 } 1814 /* 1815 * The selected interface is identified by its local 1816 * IP address. Find the interface and confirm that 1817 * it supports multicasting. 1818 */ 1819 crit_enter(); 1820 ifp = ip_multicast_if(&addr, &ifindex); 1821 if (ifp == NULL || !(ifp->if_flags & IFF_MULTICAST)) { 1822 crit_exit(); 1823 error = EADDRNOTAVAIL; 1824 break; 1825 } 1826 imo->imo_multicast_ifp = ifp; 1827 if (ifindex) 1828 imo->imo_multicast_addr = addr; 1829 else 1830 imo->imo_multicast_addr.s_addr = INADDR_ANY; 1831 crit_exit(); 1832 break; 1833 1834 case IP_MULTICAST_TTL: 1835 /* 1836 * Set the IP time-to-live for outgoing multicast packets. 1837 * The original multicast API required a char argument, 1838 * which is inconsistent with the rest of the socket API. 1839 * We allow either a char or an int. 1840 */ 1841 if (sopt->sopt_valsize == 1) { 1842 u_char ttl; 1843 error = soopt_to_kbuf(sopt, &ttl, 1, 1); 1844 if (error) 1845 break; 1846 imo->imo_multicast_ttl = ttl; 1847 } else { 1848 u_int ttl; 1849 error = soopt_to_kbuf(sopt, &ttl, sizeof ttl, sizeof ttl); 1850 if (error) 1851 break; 1852 if (ttl > 255) 1853 error = EINVAL; 1854 else 1855 imo->imo_multicast_ttl = ttl; 1856 } 1857 break; 1858 1859 case IP_MULTICAST_LOOP: 1860 /* 1861 * Set the loopback flag for outgoing multicast packets. 1862 * Must be zero or one. The original multicast API required a 1863 * char argument, which is inconsistent with the rest 1864 * of the socket API. We allow either a char or an int. 1865 */ 1866 if (sopt->sopt_valsize == 1) { 1867 u_char loop; 1868 1869 error = soopt_to_kbuf(sopt, &loop, 1, 1); 1870 if (error) 1871 break; 1872 imo->imo_multicast_loop = !!loop; 1873 } else { 1874 u_int loop; 1875 1876 error = soopt_to_kbuf(sopt, &loop, sizeof loop, 1877 sizeof loop); 1878 if (error) 1879 break; 1880 imo->imo_multicast_loop = !!loop; 1881 } 1882 break; 1883 1884 case IP_ADD_MEMBERSHIP: 1885 /* 1886 * Add a multicast group membership. 1887 * Group must be a valid IP multicast address. 1888 */ 1889 error = soopt_to_kbuf(sopt, &mreq, sizeof mreq, sizeof mreq); 1890 if (error) 1891 break; 1892 1893 if (!IN_MULTICAST(ntohl(mreq.imr_multiaddr.s_addr))) { 1894 error = EINVAL; 1895 break; 1896 } 1897 crit_enter(); 1898 /* 1899 * If no interface address was provided, use the interface of 1900 * the route to the given multicast address. 1901 */ 1902 if (mreq.imr_interface.s_addr == INADDR_ANY) { 1903 struct sockaddr_in dst; 1904 struct rtentry *rt; 1905 1906 bzero(&dst, sizeof(struct sockaddr_in)); 1907 dst.sin_len = sizeof(struct sockaddr_in); 1908 dst.sin_family = AF_INET; 1909 dst.sin_addr = mreq.imr_multiaddr; 1910 rt = rtlookup((struct sockaddr *)&dst); 1911 if (rt == NULL) { 1912 error = EADDRNOTAVAIL; 1913 crit_exit(); 1914 break; 1915 } 1916 --rt->rt_refcnt; 1917 ifp = rt->rt_ifp; 1918 } else { 1919 ifp = ip_multicast_if(&mreq.imr_interface, NULL); 1920 } 1921 1922 /* 1923 * See if we found an interface, and confirm that it 1924 * supports multicast. 1925 */ 1926 if (ifp == NULL || !(ifp->if_flags & IFF_MULTICAST)) { 1927 error = EADDRNOTAVAIL; 1928 crit_exit(); 1929 break; 1930 } 1931 /* 1932 * See if the membership already exists or if all the 1933 * membership slots are full. 1934 */ 1935 for (i = 0; i < imo->imo_num_memberships; ++i) { 1936 if (imo->imo_membership[i]->inm_ifp == ifp && 1937 imo->imo_membership[i]->inm_addr.s_addr 1938 == mreq.imr_multiaddr.s_addr) 1939 break; 1940 } 1941 if (i < imo->imo_num_memberships) { 1942 error = EADDRINUSE; 1943 crit_exit(); 1944 break; 1945 } 1946 if (i == IP_MAX_MEMBERSHIPS) { 1947 error = ETOOMANYREFS; 1948 crit_exit(); 1949 break; 1950 } 1951 /* 1952 * Everything looks good; add a new record to the multicast 1953 * address list for the given interface. 1954 */ 1955 if ((imo->imo_membership[i] = 1956 in_addmulti(&mreq.imr_multiaddr, ifp)) == NULL) { 1957 error = ENOBUFS; 1958 crit_exit(); 1959 break; 1960 } 1961 ++imo->imo_num_memberships; 1962 crit_exit(); 1963 break; 1964 1965 case IP_DROP_MEMBERSHIP: 1966 /* 1967 * Drop a multicast group membership. 1968 * Group must be a valid IP multicast address. 1969 */ 1970 error = soopt_to_kbuf(sopt, &mreq, sizeof mreq, sizeof mreq); 1971 if (error) 1972 break; 1973 1974 if (!IN_MULTICAST(ntohl(mreq.imr_multiaddr.s_addr))) { 1975 error = EINVAL; 1976 break; 1977 } 1978 1979 crit_enter(); 1980 /* 1981 * If an interface address was specified, get a pointer 1982 * to its ifnet structure. 1983 */ 1984 if (mreq.imr_interface.s_addr == INADDR_ANY) 1985 ifp = NULL; 1986 else { 1987 ifp = ip_multicast_if(&mreq.imr_interface, NULL); 1988 if (ifp == NULL) { 1989 error = EADDRNOTAVAIL; 1990 crit_exit(); 1991 break; 1992 } 1993 } 1994 /* 1995 * Find the membership in the membership array. 1996 */ 1997 for (i = 0; i < imo->imo_num_memberships; ++i) { 1998 if ((ifp == NULL || 1999 imo->imo_membership[i]->inm_ifp == ifp) && 2000 imo->imo_membership[i]->inm_addr.s_addr == 2001 mreq.imr_multiaddr.s_addr) 2002 break; 2003 } 2004 if (i == imo->imo_num_memberships) { 2005 error = EADDRNOTAVAIL; 2006 crit_exit(); 2007 break; 2008 } 2009 /* 2010 * Give up the multicast address record to which the 2011 * membership points. 2012 */ 2013 in_delmulti(imo->imo_membership[i]); 2014 /* 2015 * Remove the gap in the membership array. 2016 */ 2017 for (++i; i < imo->imo_num_memberships; ++i) 2018 imo->imo_membership[i-1] = imo->imo_membership[i]; 2019 --imo->imo_num_memberships; 2020 crit_exit(); 2021 break; 2022 2023 default: 2024 error = EOPNOTSUPP; 2025 break; 2026 } 2027 2028 /* 2029 * If all options have default values, no need to keep the mbuf. 2030 */ 2031 if (imo->imo_multicast_ifp == NULL && 2032 imo->imo_multicast_vif == -1 && 2033 imo->imo_multicast_ttl == IP_DEFAULT_MULTICAST_TTL && 2034 imo->imo_multicast_loop == IP_DEFAULT_MULTICAST_LOOP && 2035 imo->imo_num_memberships == 0) { 2036 kfree(*imop, M_IPMOPTS); 2037 *imop = NULL; 2038 } 2039 2040 return (error); 2041 } 2042 2043 /* 2044 * Return the IP multicast options in response to user getsockopt(). 2045 */ 2046 static int 2047 ip_getmoptions(struct sockopt *sopt, struct ip_moptions *imo) 2048 { 2049 struct in_addr addr; 2050 struct in_ifaddr *ia; 2051 int error, optval; 2052 u_char coptval; 2053 2054 error = 0; 2055 switch (sopt->sopt_name) { 2056 case IP_MULTICAST_VIF: 2057 if (imo != NULL) 2058 optval = imo->imo_multicast_vif; 2059 else 2060 optval = -1; 2061 soopt_from_kbuf(sopt, &optval, sizeof optval); 2062 break; 2063 2064 case IP_MULTICAST_IF: 2065 if (imo == NULL || imo->imo_multicast_ifp == NULL) 2066 addr.s_addr = INADDR_ANY; 2067 else if (imo->imo_multicast_addr.s_addr) { 2068 /* return the value user has set */ 2069 addr = imo->imo_multicast_addr; 2070 } else { 2071 ia = IFP_TO_IA(imo->imo_multicast_ifp); 2072 addr.s_addr = (ia == NULL) ? INADDR_ANY 2073 : IA_SIN(ia)->sin_addr.s_addr; 2074 } 2075 soopt_from_kbuf(sopt, &addr, sizeof addr); 2076 break; 2077 2078 case IP_MULTICAST_TTL: 2079 if (imo == NULL) 2080 optval = coptval = IP_DEFAULT_MULTICAST_TTL; 2081 else 2082 optval = coptval = imo->imo_multicast_ttl; 2083 if (sopt->sopt_valsize == 1) 2084 soopt_from_kbuf(sopt, &coptval, 1); 2085 else 2086 soopt_from_kbuf(sopt, &optval, sizeof optval); 2087 break; 2088 2089 case IP_MULTICAST_LOOP: 2090 if (imo == NULL) 2091 optval = coptval = IP_DEFAULT_MULTICAST_LOOP; 2092 else 2093 optval = coptval = imo->imo_multicast_loop; 2094 if (sopt->sopt_valsize == 1) 2095 soopt_from_kbuf(sopt, &coptval, 1); 2096 else 2097 soopt_from_kbuf(sopt, &optval, sizeof optval); 2098 break; 2099 2100 default: 2101 error = ENOPROTOOPT; 2102 break; 2103 } 2104 return (error); 2105 } 2106 2107 /* 2108 * Discard the IP multicast options. 2109 */ 2110 void 2111 ip_freemoptions(struct ip_moptions *imo) 2112 { 2113 int i; 2114 2115 if (imo != NULL) { 2116 for (i = 0; i < imo->imo_num_memberships; ++i) 2117 in_delmulti(imo->imo_membership[i]); 2118 kfree(imo, M_IPMOPTS); 2119 } 2120 } 2121 2122 /* 2123 * Routine called from ip_output() to loop back a copy of an IP multicast 2124 * packet to the input queue of a specified interface. Note that this 2125 * calls the output routine of the loopback "driver", but with an interface 2126 * pointer that might NOT be a loopback interface -- evil, but easier than 2127 * replicating that code here. 2128 */ 2129 static void 2130 ip_mloopback(struct ifnet *ifp, struct mbuf *m, struct sockaddr_in *dst, 2131 int hlen) 2132 { 2133 struct ip *ip; 2134 struct mbuf *copym; 2135 2136 copym = m_copypacket(m, MB_DONTWAIT); 2137 if (copym != NULL && (copym->m_flags & M_EXT || copym->m_len < hlen)) 2138 copym = m_pullup(copym, hlen); 2139 if (copym != NULL) { 2140 /* 2141 * if the checksum hasn't been computed, mark it as valid 2142 */ 2143 if (copym->m_pkthdr.csum_flags & CSUM_DELAY_DATA) { 2144 in_delayed_cksum(copym); 2145 copym->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA; 2146 copym->m_pkthdr.csum_flags |= 2147 CSUM_DATA_VALID | CSUM_PSEUDO_HDR; 2148 copym->m_pkthdr.csum_data = 0xffff; 2149 } 2150 /* 2151 * We don't bother to fragment if the IP length is greater 2152 * than the interface's MTU. Can this possibly matter? 2153 */ 2154 ip = mtod(copym, struct ip *); 2155 ip->ip_len = htons(ip->ip_len); 2156 ip->ip_off = htons(ip->ip_off); 2157 ip->ip_sum = 0; 2158 if (ip->ip_vhl == IP_VHL_BORING) { 2159 ip->ip_sum = in_cksum_hdr(ip); 2160 } else { 2161 ip->ip_sum = in_cksum(copym, hlen); 2162 } 2163 /* 2164 * NB: 2165 * It's not clear whether there are any lingering 2166 * reentrancy problems in other areas which might 2167 * be exposed by using ip_input directly (in 2168 * particular, everything which modifies the packet 2169 * in-place). Yet another option is using the 2170 * protosw directly to deliver the looped back 2171 * packet. For the moment, we'll err on the side 2172 * of safety by using if_simloop(). 2173 */ 2174 #if 1 /* XXX */ 2175 if (dst->sin_family != AF_INET) { 2176 kprintf("ip_mloopback: bad address family %d\n", 2177 dst->sin_family); 2178 dst->sin_family = AF_INET; 2179 } 2180 #endif 2181 if_simloop(ifp, copym, dst->sin_family, 0); 2182 } 2183 } 2184