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 */ 32 33 #define _IP_VHL 34 35 #include "opt_ipfw.h" 36 #include "opt_ipdn.h" 37 #include "opt_ipdivert.h" 38 #include "opt_ipsec.h" 39 #include "opt_mbuf_stress_test.h" 40 #include "opt_mpls.h" 41 42 #include <sys/param.h> 43 #include <sys/systm.h> 44 #include <sys/kernel.h> 45 #include <sys/malloc.h> 46 #include <sys/mbuf.h> 47 #include <sys/protosw.h> 48 #include <sys/socket.h> 49 #include <sys/socketvar.h> 50 #include <sys/proc.h> 51 #include <sys/priv.h> 52 #include <sys/sysctl.h> 53 #include <sys/in_cksum.h> 54 #include <sys/lock.h> 55 56 #include <sys/thread2.h> 57 #include <sys/mplock2.h> 58 #include <sys/msgport2.h> 59 60 #include <net/if.h> 61 #include <net/netisr.h> 62 #include <net/pfil.h> 63 #include <net/route.h> 64 65 #include <netinet/in.h> 66 #include <netinet/in_systm.h> 67 #include <netinet/ip.h> 68 #include <netinet/in_pcb.h> 69 #include <netinet/in_var.h> 70 #include <netinet/ip_var.h> 71 72 #include <netproto/mpls/mpls_var.h> 73 74 static MALLOC_DEFINE(M_IPMOPTS, "ip_moptions", "internet multicast options"); 75 76 #ifdef IPSEC 77 #include <netinet6/ipsec.h> 78 #include <netproto/key/key.h> 79 #ifdef IPSEC_DEBUG 80 #include <netproto/key/key_debug.h> 81 #else 82 #define KEYDEBUG(lev,arg) 83 #endif 84 #endif /*IPSEC*/ 85 86 #ifdef FAST_IPSEC 87 #include <netproto/ipsec/ipsec.h> 88 #include <netproto/ipsec/xform.h> 89 #include <netproto/ipsec/key.h> 90 #endif /*FAST_IPSEC*/ 91 92 #include <net/ipfw/ip_fw.h> 93 #include <net/dummynet/ip_dummynet.h> 94 95 #define print_ip(x, a, y) kprintf("%s %d.%d.%d.%d%s",\ 96 x, (ntohl(a.s_addr)>>24)&0xFF,\ 97 (ntohl(a.s_addr)>>16)&0xFF,\ 98 (ntohl(a.s_addr)>>8)&0xFF,\ 99 (ntohl(a.s_addr))&0xFF, y); 100 101 u_short ip_id; 102 103 #ifdef MBUF_STRESS_TEST 104 int mbuf_frag_size = 0; 105 SYSCTL_INT(_net_inet_ip, OID_AUTO, mbuf_frag_size, CTLFLAG_RW, 106 &mbuf_frag_size, 0, "Fragment outgoing mbufs to this size"); 107 #endif 108 109 static struct mbuf *ip_insertoptions(struct mbuf *, struct mbuf *, int *); 110 static struct ifnet *ip_multicast_if(struct in_addr *, int *); 111 static void ip_mloopback 112 (struct ifnet *, struct mbuf *, struct sockaddr_in *, int); 113 static int ip_getmoptions 114 (struct sockopt *, struct ip_moptions *); 115 static int ip_pcbopts(int, struct mbuf **, struct mbuf *); 116 static int ip_setmoptions 117 (struct sockopt *, struct ip_moptions **); 118 119 int ip_optcopy(struct ip *, struct ip *); 120 121 extern int route_assert_owner_access; 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 print_backtrace(-1); 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 dst = (struct sockaddr_in *)&ro->ro_dst; 308 /* 309 * If there is a cached route, 310 * check that it is to the same destination 311 * and is still up. If not, free it and try again. 312 * The address family should also be checked in case of sharing the 313 * cache with IPv6. 314 */ 315 if (ro->ro_rt && 316 (!(ro->ro_rt->rt_flags & RTF_UP) || 317 dst->sin_family != AF_INET || 318 dst->sin_addr.s_addr != pkt_dst.s_addr)) { 319 rtfree(ro->ro_rt); 320 ro->ro_rt = NULL; 321 } 322 if (ro->ro_rt == NULL) { 323 bzero(dst, sizeof *dst); 324 dst->sin_family = AF_INET; 325 dst->sin_len = sizeof *dst; 326 dst->sin_addr = pkt_dst; 327 } 328 /* 329 * If routing to interface only, 330 * short circuit routing lookup. 331 */ 332 if (flags & IP_ROUTETOIF) { 333 if ((ia = ifatoia(ifa_ifwithdstaddr(sintosa(dst)))) == NULL && 334 (ia = ifatoia(ifa_ifwithnet(sintosa(dst)))) == NULL) { 335 ipstat.ips_noroute++; 336 error = ENETUNREACH; 337 goto bad; 338 } 339 ifp = ia->ia_ifp; 340 ip->ip_ttl = 1; 341 isbroadcast = in_broadcast(dst->sin_addr, ifp); 342 } else if (IN_MULTICAST(ntohl(pkt_dst.s_addr)) && 343 imo != NULL && imo->imo_multicast_ifp != NULL) { 344 /* 345 * Bypass the normal routing lookup for multicast 346 * packets if the interface is specified. 347 */ 348 ifp = imo->imo_multicast_ifp; 349 ia = IFP_TO_IA(ifp); 350 isbroadcast = 0; /* fool gcc */ 351 } else { 352 /* 353 * If this is the case, we probably don't want to allocate 354 * a protocol-cloned route since we didn't get one from the 355 * ULP. This lets TCP do its thing, while not burdening 356 * forwarding or ICMP with the overhead of cloning a route. 357 * Of course, we still want to do any cloning requested by 358 * the link layer, as this is probably required in all cases 359 * for correct operation (as it is for ARP). 360 */ 361 if (ro->ro_rt == NULL) 362 rtalloc_ign(ro, RTF_PRCLONING); 363 if (ro->ro_rt == NULL) { 364 ipstat.ips_noroute++; 365 error = EHOSTUNREACH; 366 goto bad; 367 } 368 ia = ifatoia(ro->ro_rt->rt_ifa); 369 ifp = ro->ro_rt->rt_ifp; 370 ro->ro_rt->rt_use++; 371 if (ro->ro_rt->rt_flags & RTF_GATEWAY) 372 dst = (struct sockaddr_in *)ro->ro_rt->rt_gateway; 373 if (ro->ro_rt->rt_flags & RTF_HOST) 374 isbroadcast = (ro->ro_rt->rt_flags & RTF_BROADCAST); 375 else 376 isbroadcast = in_broadcast(dst->sin_addr, ifp); 377 } 378 if (IN_MULTICAST(ntohl(pkt_dst.s_addr))) { 379 struct in_multi *inm; 380 381 m->m_flags |= M_MCAST; 382 /* 383 * IP destination address is multicast. Make sure "dst" 384 * still points to the address in "ro". (It may have been 385 * changed to point to a gateway address, above.) 386 */ 387 dst = (struct sockaddr_in *)&ro->ro_dst; 388 /* 389 * See if the caller provided any multicast options 390 */ 391 if (imo != NULL) { 392 ip->ip_ttl = imo->imo_multicast_ttl; 393 if (imo->imo_multicast_vif != -1) { 394 ip->ip_src.s_addr = 395 ip_mcast_src ? 396 ip_mcast_src(imo->imo_multicast_vif) : 397 INADDR_ANY; 398 } 399 } else { 400 ip->ip_ttl = IP_DEFAULT_MULTICAST_TTL; 401 } 402 /* 403 * Confirm that the outgoing interface supports multicast. 404 */ 405 if ((imo == NULL) || (imo->imo_multicast_vif == -1)) { 406 if (!(ifp->if_flags & IFF_MULTICAST)) { 407 ipstat.ips_noroute++; 408 error = ENETUNREACH; 409 goto bad; 410 } 411 } 412 /* 413 * If source address not specified yet, use address 414 * of outgoing interface. 415 */ 416 if (ip->ip_src.s_addr == INADDR_ANY) { 417 /* Interface may have no addresses. */ 418 if (ia != NULL) 419 ip->ip_src = IA_SIN(ia)->sin_addr; 420 } 421 422 IN_LOOKUP_MULTI(pkt_dst, ifp, inm); 423 if (inm != NULL && 424 (imo == NULL || imo->imo_multicast_loop)) { 425 /* 426 * If we belong to the destination multicast group 427 * on the outgoing interface, and the caller did not 428 * forbid loopback, loop back a copy. 429 */ 430 ip_mloopback(ifp, m, dst, hlen); 431 } else { 432 /* 433 * If we are acting as a multicast router, perform 434 * multicast forwarding as if the packet had just 435 * arrived on the interface to which we are about 436 * to send. The multicast forwarding function 437 * recursively calls this function, using the 438 * IP_FORWARDING flag to prevent infinite recursion. 439 * 440 * Multicasts that are looped back by ip_mloopback(), 441 * above, will be forwarded by the ip_input() routine, 442 * if necessary. 443 */ 444 if (ip_mrouter && !(flags & IP_FORWARDING)) { 445 /* 446 * If rsvp daemon is not running, do not 447 * set ip_moptions. This ensures that the packet 448 * is multicast and not just sent down one link 449 * as prescribed by rsvpd. 450 */ 451 if (!rsvp_on) 452 imo = NULL; 453 if (ip_mforward) { 454 get_mplock(); 455 if (ip_mforward(ip, ifp, m, imo) != 0) { 456 m_freem(m); 457 rel_mplock(); 458 goto done; 459 } 460 rel_mplock(); 461 } 462 } 463 } 464 465 /* 466 * Multicasts with a time-to-live of zero may be looped- 467 * back, above, but must not be transmitted on a network. 468 * Also, multicasts addressed to the loopback interface 469 * are not sent -- the above call to ip_mloopback() will 470 * loop back a copy if this host actually belongs to the 471 * destination group on the loopback interface. 472 */ 473 if (ip->ip_ttl == 0 || ifp->if_flags & IFF_LOOPBACK) { 474 m_freem(m); 475 goto done; 476 } 477 478 goto sendit; 479 } else { 480 m->m_flags &= ~M_MCAST; 481 } 482 483 /* 484 * If the source address is not specified yet, use the address 485 * of the outoing interface. In case, keep note we did that, so 486 * if the the firewall changes the next-hop causing the output 487 * interface to change, we can fix that. 488 */ 489 if (ip->ip_src.s_addr == INADDR_ANY || src_was_INADDR_ANY) { 490 /* Interface may have no addresses. */ 491 if (ia != NULL) { 492 ip->ip_src = IA_SIN(ia)->sin_addr; 493 src_was_INADDR_ANY = 1; 494 } 495 } 496 497 #ifdef ALTQ 498 /* 499 * Disable packet drop hack. 500 * Packetdrop should be done by queueing. 501 */ 502 #else /* !ALTQ */ 503 /* 504 * Verify that we have any chance at all of being able to queue 505 * the packet or packet fragments 506 */ 507 if ((ifp->if_snd.ifq_len + ip->ip_len / ifp->if_mtu + 1) >= 508 ifp->if_snd.ifq_maxlen) { 509 error = ENOBUFS; 510 ipstat.ips_odropped++; 511 goto bad; 512 } 513 #endif /* !ALTQ */ 514 515 /* 516 * Look for broadcast address and 517 * verify user is allowed to send 518 * such a packet. 519 */ 520 if (isbroadcast) { 521 if (!(ifp->if_flags & IFF_BROADCAST)) { 522 error = EADDRNOTAVAIL; 523 goto bad; 524 } 525 if (!(flags & IP_ALLOWBROADCAST)) { 526 error = EACCES; 527 goto bad; 528 } 529 /* don't allow broadcast messages to be fragmented */ 530 if (ip->ip_len > ifp->if_mtu) { 531 error = EMSGSIZE; 532 goto bad; 533 } 534 m->m_flags |= M_BCAST; 535 } else { 536 m->m_flags &= ~M_BCAST; 537 } 538 539 sendit: 540 #ifdef IPSEC 541 /* get SP for this packet */ 542 if (so == NULL) 543 sp = ipsec4_getpolicybyaddr(m, IPSEC_DIR_OUTBOUND, flags, &error); 544 else 545 sp = ipsec4_getpolicybysock(m, IPSEC_DIR_OUTBOUND, so, &error); 546 547 if (sp == NULL) { 548 ipsecstat.out_inval++; 549 goto bad; 550 } 551 552 error = 0; 553 554 /* check policy */ 555 switch (sp->policy) { 556 case IPSEC_POLICY_DISCARD: 557 /* 558 * This packet is just discarded. 559 */ 560 ipsecstat.out_polvio++; 561 goto bad; 562 563 case IPSEC_POLICY_BYPASS: 564 case IPSEC_POLICY_NONE: 565 case IPSEC_POLICY_TCP: 566 /* no need to do IPsec. */ 567 goto skip_ipsec; 568 569 case IPSEC_POLICY_IPSEC: 570 if (sp->req == NULL) { 571 /* acquire a policy */ 572 error = key_spdacquire(sp); 573 goto bad; 574 } 575 break; 576 577 case IPSEC_POLICY_ENTRUST: 578 default: 579 kprintf("ip_output: Invalid policy found. %d\n", sp->policy); 580 } 581 { 582 struct ipsec_output_state state; 583 bzero(&state, sizeof state); 584 state.m = m; 585 if (flags & IP_ROUTETOIF) { 586 state.ro = &iproute; 587 bzero(&iproute, sizeof iproute); 588 } else 589 state.ro = ro; 590 state.dst = (struct sockaddr *)dst; 591 592 ip->ip_sum = 0; 593 594 /* 595 * XXX 596 * delayed checksums are not currently compatible with IPsec 597 */ 598 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) { 599 in_delayed_cksum(m); 600 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA; 601 } 602 603 ip->ip_len = htons(ip->ip_len); 604 ip->ip_off = htons(ip->ip_off); 605 606 error = ipsec4_output(&state, sp, flags); 607 608 m = state.m; 609 if (flags & IP_ROUTETOIF) { 610 /* 611 * if we have tunnel mode SA, we may need to ignore 612 * IP_ROUTETOIF. 613 */ 614 if (state.ro != &iproute || state.ro->ro_rt != NULL) { 615 flags &= ~IP_ROUTETOIF; 616 ro = state.ro; 617 } 618 } else 619 ro = state.ro; 620 dst = (struct sockaddr_in *)state.dst; 621 if (error) { 622 /* mbuf is already reclaimed in ipsec4_output. */ 623 m0 = NULL; 624 switch (error) { 625 case EHOSTUNREACH: 626 case ENETUNREACH: 627 case EMSGSIZE: 628 case ENOBUFS: 629 case ENOMEM: 630 break; 631 default: 632 kprintf("ip4_output (ipsec): error code %d\n", error); 633 /*fall through*/ 634 case ENOENT: 635 /* don't show these error codes to the user */ 636 error = 0; 637 break; 638 } 639 goto bad; 640 } 641 } 642 643 /* be sure to update variables that are affected by ipsec4_output() */ 644 ip = mtod(m, struct ip *); 645 #ifdef _IP_VHL 646 hlen = IP_VHL_HL(ip->ip_vhl) << 2; 647 #else 648 hlen = ip->ip_hl << 2; 649 #endif 650 if (ro->ro_rt == NULL) { 651 if (!(flags & IP_ROUTETOIF)) { 652 kprintf("ip_output: " 653 "can't update route after IPsec processing\n"); 654 error = EHOSTUNREACH; /*XXX*/ 655 goto bad; 656 } 657 } else { 658 ia = ifatoia(ro->ro_rt->rt_ifa); 659 ifp = ro->ro_rt->rt_ifp; 660 } 661 662 /* make it flipped, again. */ 663 ip->ip_len = ntohs(ip->ip_len); 664 ip->ip_off = ntohs(ip->ip_off); 665 skip_ipsec: 666 #endif /*IPSEC*/ 667 #ifdef FAST_IPSEC 668 /* 669 * Check the security policy (SP) for the packet and, if 670 * required, do IPsec-related processing. There are two 671 * cases here; the first time a packet is sent through 672 * it will be untagged and handled by ipsec4_checkpolicy. 673 * If the packet is resubmitted to ip_output (e.g. after 674 * AH, ESP, etc. processing), there will be a tag to bypass 675 * the lookup and related policy checking. 676 */ 677 mtag = m_tag_find(m, PACKET_TAG_IPSEC_PENDING_TDB, NULL); 678 crit_enter(); 679 if (mtag != NULL) { 680 tdbi = (struct tdb_ident *)m_tag_data(mtag); 681 sp = ipsec_getpolicy(tdbi, IPSEC_DIR_OUTBOUND); 682 if (sp == NULL) 683 error = -EINVAL; /* force silent drop */ 684 m_tag_delete(m, mtag); 685 } else { 686 sp = ipsec4_checkpolicy(m, IPSEC_DIR_OUTBOUND, flags, 687 &error, inp); 688 } 689 /* 690 * There are four return cases: 691 * sp != NULL apply IPsec policy 692 * sp == NULL, error == 0 no IPsec handling needed 693 * sp == NULL, error == -EINVAL discard packet w/o error 694 * sp == NULL, error != 0 discard packet, report error 695 */ 696 if (sp != NULL) { 697 /* Loop detection, check if ipsec processing already done */ 698 KASSERT(sp->req != NULL, ("ip_output: no ipsec request")); 699 for (mtag = m_tag_first(m); mtag != NULL; 700 mtag = m_tag_next(m, mtag)) { 701 if (mtag->m_tag_cookie != MTAG_ABI_COMPAT) 702 continue; 703 if (mtag->m_tag_id != PACKET_TAG_IPSEC_OUT_DONE && 704 mtag->m_tag_id != PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED) 705 continue; 706 /* 707 * Check if policy has an SA associated with it. 708 * This can happen when an SP has yet to acquire 709 * an SA; e.g. on first reference. If it occurs, 710 * then we let ipsec4_process_packet do its thing. 711 */ 712 if (sp->req->sav == NULL) 713 break; 714 tdbi = (struct tdb_ident *)m_tag_data(mtag); 715 if (tdbi->spi == sp->req->sav->spi && 716 tdbi->proto == sp->req->sav->sah->saidx.proto && 717 bcmp(&tdbi->dst, &sp->req->sav->sah->saidx.dst, 718 sizeof(union sockaddr_union)) == 0) { 719 /* 720 * No IPsec processing is needed, free 721 * reference to SP. 722 * 723 * NB: null pointer to avoid free at 724 * done: below. 725 */ 726 KEY_FREESP(&sp), sp = NULL; 727 crit_exit(); 728 goto spd_done; 729 } 730 } 731 732 /* 733 * Do delayed checksums now because we send before 734 * this is done in the normal processing path. 735 */ 736 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) { 737 in_delayed_cksum(m); 738 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA; 739 } 740 741 ip->ip_len = htons(ip->ip_len); 742 ip->ip_off = htons(ip->ip_off); 743 744 /* NB: callee frees mbuf */ 745 error = ipsec4_process_packet(m, sp->req, flags, 0); 746 /* 747 * Preserve KAME behaviour: ENOENT can be returned 748 * when an SA acquire is in progress. Don't propagate 749 * this to user-level; it confuses applications. 750 * 751 * XXX this will go away when the SADB is redone. 752 */ 753 if (error == ENOENT) 754 error = 0; 755 crit_exit(); 756 goto done; 757 } else { 758 crit_exit(); 759 760 if (error != 0) { 761 /* 762 * Hack: -EINVAL is used to signal that a packet 763 * should be silently discarded. This is typically 764 * because we asked key management for an SA and 765 * it was delayed (e.g. kicked up to IKE). 766 */ 767 if (error == -EINVAL) 768 error = 0; 769 goto bad; 770 } else { 771 /* No IPsec processing for this packet. */ 772 } 773 #ifdef notyet 774 /* 775 * If deferred crypto processing is needed, check that 776 * the interface supports it. 777 */ 778 mtag = m_tag_find(m, PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED, NULL); 779 if (mtag != NULL && !(ifp->if_capenable & IFCAP_IPSEC)) { 780 /* notify IPsec to do its own crypto */ 781 ipsp_skipcrypto_unmark((struct tdb_ident *)m_tag_data(mtag)); 782 error = EHOSTUNREACH; 783 goto bad; 784 } 785 #endif 786 } 787 spd_done: 788 #endif /* FAST_IPSEC */ 789 790 /* We are already being fwd'd from a firewall. */ 791 if (next_hop != NULL) 792 goto pass; 793 794 /* No pfil hooks */ 795 if (!pfil_has_hooks(&inet_pfil_hook)) { 796 if (m->m_pkthdr.fw_flags & DUMMYNET_MBUF_TAGGED) { 797 /* 798 * Strip dummynet tags from stranded packets 799 */ 800 mtag = m_tag_find(m, PACKET_TAG_DUMMYNET, NULL); 801 KKASSERT(mtag != NULL); 802 m_tag_delete(m, mtag); 803 m->m_pkthdr.fw_flags &= ~DUMMYNET_MBUF_TAGGED; 804 } 805 goto pass; 806 } 807 808 /* 809 * IpHack's section. 810 * - Xlate: translate packet's addr/port (NAT). 811 * - Firewall: deny/allow/etc. 812 * - Wrap: fake packet's addr/port <unimpl.> 813 * - Encapsulate: put it in another IP and send out. <unimp.> 814 */ 815 816 /* 817 * Run through list of hooks for output packets. 818 */ 819 error = pfil_run_hooks(&inet_pfil_hook, &m, ifp, PFIL_OUT); 820 if (error != 0 || m == NULL) 821 goto done; 822 ip = mtod(m, struct ip *); 823 824 if (m->m_pkthdr.fw_flags & IPFORWARD_MBUF_TAGGED) { 825 /* 826 * Check dst to make sure it is directly reachable on the 827 * interface we previously thought it was. 828 * If it isn't (which may be likely in some situations) we have 829 * to re-route it (ie, find a route for the next-hop and the 830 * associated interface) and set them here. This is nested 831 * forwarding which in most cases is undesirable, except where 832 * such control is nigh impossible. So we do it here. 833 * And I'm babbling. 834 */ 835 mtag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL); 836 KKASSERT(mtag != NULL); 837 next_hop = m_tag_data(mtag); 838 839 /* 840 * Try local forwarding first 841 */ 842 if (ip_localforward(m, next_hop, hlen)) 843 goto done; 844 845 /* 846 * Relocate the route based on next_hop. 847 * If the current route is inp's cache, keep it untouched. 848 */ 849 if (ro == &iproute && ro->ro_rt != NULL) { 850 RTFREE(ro->ro_rt); 851 ro->ro_rt = NULL; 852 } 853 ro = &iproute; 854 bzero(ro, sizeof *ro); 855 856 /* 857 * Forwarding to broadcast address is not allowed. 858 * XXX Should we follow IP_ROUTETOIF? 859 */ 860 flags &= ~(IP_ALLOWBROADCAST | IP_ROUTETOIF); 861 862 /* We are doing forwarding now */ 863 flags |= IP_FORWARDING; 864 865 goto reroute; 866 } 867 868 if (m->m_pkthdr.fw_flags & DUMMYNET_MBUF_TAGGED) { 869 struct dn_pkt *dn_pkt; 870 871 mtag = m_tag_find(m, PACKET_TAG_DUMMYNET, NULL); 872 KKASSERT(mtag != NULL); 873 dn_pkt = m_tag_data(mtag); 874 875 /* 876 * Under certain cases it is not possible to recalculate 877 * 'ro' and 'dst', let alone 'flags', so just save them in 878 * dummynet tag and avoid the possible wrong reculcalation 879 * when we come back to ip_output() again. 880 * 881 * All other parameters have been already used and so they 882 * are not needed anymore. 883 * XXX if the ifp is deleted while a pkt is in dummynet, 884 * we are in trouble! (TODO use ifnet_detach_event) 885 * 886 * We need to copy *ro because for ICMP pkts (and maybe 887 * others) the caller passed a pointer into the stack; 888 * dst might also be a pointer into *ro so it needs to 889 * be updated. 890 */ 891 dn_pkt->ro = *ro; 892 if (ro->ro_rt) 893 ro->ro_rt->rt_refcnt++; 894 if (dst == (struct sockaddr_in *)&ro->ro_dst) { 895 /* 'dst' points into 'ro' */ 896 dst = (struct sockaddr_in *)&(dn_pkt->ro.ro_dst); 897 } 898 dn_pkt->dn_dst = dst; 899 dn_pkt->flags = flags; 900 901 ip_dn_queue(m); 902 goto done; 903 } 904 pass: 905 /* 127/8 must not appear on wire - RFC1122. */ 906 if ((ntohl(ip->ip_dst.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET || 907 (ntohl(ip->ip_src.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET) { 908 if (!(ifp->if_flags & IFF_LOOPBACK)) { 909 ipstat.ips_badaddr++; 910 error = EADDRNOTAVAIL; 911 goto bad; 912 } 913 } 914 915 m->m_pkthdr.csum_flags |= CSUM_IP; 916 sw_csum = m->m_pkthdr.csum_flags & ~ifp->if_hwassist; 917 if (sw_csum & CSUM_DELAY_DATA) { 918 in_delayed_cksum(m); 919 sw_csum &= ~CSUM_DELAY_DATA; 920 } 921 m->m_pkthdr.csum_flags &= ifp->if_hwassist; 922 923 /* 924 * If small enough for interface, or the interface will take 925 * care of the fragmentation for us, can just send directly. 926 */ 927 if (ip->ip_len <= ifp->if_mtu || ((ifp->if_hwassist & CSUM_FRAGMENT) && 928 !(ip->ip_off & IP_DF))) { 929 ip->ip_len = htons(ip->ip_len); 930 ip->ip_off = htons(ip->ip_off); 931 ip->ip_sum = 0; 932 if (sw_csum & CSUM_DELAY_IP) { 933 if (ip->ip_vhl == IP_VHL_BORING) 934 ip->ip_sum = in_cksum_hdr(ip); 935 else 936 ip->ip_sum = in_cksum(m, hlen); 937 } 938 939 /* Record statistics for this interface address. */ 940 if (!(flags & IP_FORWARDING) && ia) { 941 ia->ia_ifa.if_opackets++; 942 ia->ia_ifa.if_obytes += m->m_pkthdr.len; 943 } 944 945 #ifdef IPSEC 946 /* clean ipsec history once it goes out of the node */ 947 ipsec_delaux(m); 948 #endif 949 950 #ifdef MBUF_STRESS_TEST 951 if (mbuf_frag_size && m->m_pkthdr.len > mbuf_frag_size) { 952 struct mbuf *m1, *m2; 953 int length, tmp; 954 955 tmp = length = m->m_pkthdr.len; 956 957 while ((length -= mbuf_frag_size) >= 1) { 958 m1 = m_split(m, length, MB_DONTWAIT); 959 if (m1 == NULL) 960 break; 961 m2 = m; 962 while (m2->m_next != NULL) 963 m2 = m2->m_next; 964 m2->m_next = m1; 965 } 966 m->m_pkthdr.len = tmp; 967 } 968 #endif 969 970 #ifdef MPLS 971 if (!mpls_output_process(m, ro->ro_rt)) 972 goto done; 973 #endif 974 error = ifp->if_output(ifp, m, (struct sockaddr *)dst, 975 ro->ro_rt); 976 goto done; 977 } 978 979 if (ip->ip_off & IP_DF) { 980 error = EMSGSIZE; 981 /* 982 * This case can happen if the user changed the MTU 983 * of an interface after enabling IP on it. Because 984 * most netifs don't keep track of routes pointing to 985 * them, there is no way for one to update all its 986 * routes when the MTU is changed. 987 */ 988 if ((ro->ro_rt->rt_flags & (RTF_UP | RTF_HOST)) && 989 !(ro->ro_rt->rt_rmx.rmx_locks & RTV_MTU) && 990 (ro->ro_rt->rt_rmx.rmx_mtu > ifp->if_mtu)) { 991 ro->ro_rt->rt_rmx.rmx_mtu = ifp->if_mtu; 992 } 993 ipstat.ips_cantfrag++; 994 goto bad; 995 } 996 997 /* 998 * Too large for interface; fragment if possible. If successful, 999 * on return, m will point to a list of packets to be sent. 1000 */ 1001 error = ip_fragment(ip, &m, ifp->if_mtu, ifp->if_hwassist, sw_csum); 1002 if (error) 1003 goto bad; 1004 for (; m; m = m0) { 1005 m0 = m->m_nextpkt; 1006 m->m_nextpkt = NULL; 1007 #ifdef IPSEC 1008 /* clean ipsec history once it goes out of the node */ 1009 ipsec_delaux(m); 1010 #endif 1011 if (error == 0) { 1012 /* Record statistics for this interface address. */ 1013 if (ia != NULL) { 1014 ia->ia_ifa.if_opackets++; 1015 ia->ia_ifa.if_obytes += m->m_pkthdr.len; 1016 } 1017 #ifdef MPLS 1018 if (!mpls_output_process(m, ro->ro_rt)) 1019 continue; 1020 #endif 1021 error = ifp->if_output(ifp, m, (struct sockaddr *)dst, 1022 ro->ro_rt); 1023 } else { 1024 m_freem(m); 1025 } 1026 } 1027 1028 if (error == 0) 1029 ipstat.ips_fragmented++; 1030 1031 done: 1032 if (ro == &iproute && ro->ro_rt != NULL) { 1033 RTFREE(ro->ro_rt); 1034 ro->ro_rt = NULL; 1035 } 1036 #ifdef IPSEC 1037 if (sp != NULL) { 1038 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 1039 kprintf("DP ip_output call free SP:%p\n", sp)); 1040 key_freesp(sp); 1041 } 1042 #endif 1043 #ifdef FAST_IPSEC 1044 if (sp != NULL) 1045 KEY_FREESP(&sp); 1046 #endif 1047 return (error); 1048 bad: 1049 m_freem(m); 1050 goto done; 1051 } 1052 1053 /* 1054 * Create a chain of fragments which fit the given mtu. m_frag points to the 1055 * mbuf to be fragmented; on return it points to the chain with the fragments. 1056 * Return 0 if no error. If error, m_frag may contain a partially built 1057 * chain of fragments that should be freed by the caller. 1058 * 1059 * if_hwassist_flags is the hw offload capabilities (see if_data.ifi_hwassist) 1060 * sw_csum contains the delayed checksums flags (e.g., CSUM_DELAY_IP). 1061 */ 1062 int 1063 ip_fragment(struct ip *ip, struct mbuf **m_frag, int mtu, 1064 u_long if_hwassist_flags, int sw_csum) 1065 { 1066 int error = 0; 1067 int hlen = IP_VHL_HL(ip->ip_vhl) << 2; 1068 int len = (mtu - hlen) & ~7; /* size of payload in each fragment */ 1069 int off; 1070 struct mbuf *m0 = *m_frag; /* the original packet */ 1071 int firstlen; 1072 struct mbuf **mnext; 1073 int nfrags; 1074 1075 if (ip->ip_off & IP_DF) { /* Fragmentation not allowed */ 1076 ipstat.ips_cantfrag++; 1077 return EMSGSIZE; 1078 } 1079 1080 /* 1081 * Must be able to put at least 8 bytes per fragment. 1082 */ 1083 if (len < 8) 1084 return EMSGSIZE; 1085 1086 /* 1087 * If the interface will not calculate checksums on 1088 * fragmented packets, then do it here. 1089 */ 1090 if ((m0->m_pkthdr.csum_flags & CSUM_DELAY_DATA) && 1091 !(if_hwassist_flags & CSUM_IP_FRAGS)) { 1092 in_delayed_cksum(m0); 1093 m0->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA; 1094 } 1095 1096 if (len > PAGE_SIZE) { 1097 /* 1098 * Fragment large datagrams such that each segment 1099 * contains a multiple of PAGE_SIZE amount of data, 1100 * plus headers. This enables a receiver to perform 1101 * page-flipping zero-copy optimizations. 1102 * 1103 * XXX When does this help given that sender and receiver 1104 * could have different page sizes, and also mtu could 1105 * be less than the receiver's page size ? 1106 */ 1107 int newlen; 1108 struct mbuf *m; 1109 1110 for (m = m0, off = 0; m && (off+m->m_len) <= mtu; m = m->m_next) 1111 off += m->m_len; 1112 1113 /* 1114 * firstlen (off - hlen) must be aligned on an 1115 * 8-byte boundary 1116 */ 1117 if (off < hlen) 1118 goto smart_frag_failure; 1119 off = ((off - hlen) & ~7) + hlen; 1120 newlen = (~PAGE_MASK) & mtu; 1121 if ((newlen + sizeof(struct ip)) > mtu) { 1122 /* we failed, go back the default */ 1123 smart_frag_failure: 1124 newlen = len; 1125 off = hlen + len; 1126 } 1127 len = newlen; 1128 1129 } else { 1130 off = hlen + len; 1131 } 1132 1133 firstlen = off - hlen; 1134 mnext = &m0->m_nextpkt; /* pointer to next packet */ 1135 1136 /* 1137 * Loop through length of segment after first fragment, 1138 * make new header and copy data of each part and link onto chain. 1139 * Here, m0 is the original packet, m is the fragment being created. 1140 * The fragments are linked off the m_nextpkt of the original 1141 * packet, which after processing serves as the first fragment. 1142 */ 1143 for (nfrags = 1; off < ip->ip_len; off += len, nfrags++) { 1144 struct ip *mhip; /* ip header on the fragment */ 1145 struct mbuf *m; 1146 int mhlen = sizeof(struct ip); 1147 1148 MGETHDR(m, MB_DONTWAIT, MT_HEADER); 1149 if (m == NULL) { 1150 error = ENOBUFS; 1151 ipstat.ips_odropped++; 1152 goto done; 1153 } 1154 m->m_flags |= (m0->m_flags & M_MCAST) | M_FRAG; 1155 /* 1156 * In the first mbuf, leave room for the link header, then 1157 * copy the original IP header including options. The payload 1158 * goes into an additional mbuf chain returned by m_copy(). 1159 */ 1160 m->m_data += max_linkhdr; 1161 mhip = mtod(m, struct ip *); 1162 *mhip = *ip; 1163 if (hlen > sizeof(struct ip)) { 1164 mhlen = ip_optcopy(ip, mhip) + sizeof(struct ip); 1165 mhip->ip_vhl = IP_MAKE_VHL(IPVERSION, mhlen >> 2); 1166 } 1167 m->m_len = mhlen; 1168 /* XXX do we need to add ip->ip_off below ? */ 1169 mhip->ip_off = ((off - hlen) >> 3) + ip->ip_off; 1170 if (off + len >= ip->ip_len) { /* last fragment */ 1171 len = ip->ip_len - off; 1172 m->m_flags |= M_LASTFRAG; 1173 } else 1174 mhip->ip_off |= IP_MF; 1175 mhip->ip_len = htons((u_short)(len + mhlen)); 1176 m->m_next = m_copy(m0, off, len); 1177 if (m->m_next == NULL) { /* copy failed */ 1178 m_free(m); 1179 error = ENOBUFS; /* ??? */ 1180 ipstat.ips_odropped++; 1181 goto done; 1182 } 1183 m->m_pkthdr.len = mhlen + len; 1184 m->m_pkthdr.rcvif = NULL; 1185 m->m_pkthdr.csum_flags = m0->m_pkthdr.csum_flags; 1186 mhip->ip_off = htons(mhip->ip_off); 1187 mhip->ip_sum = 0; 1188 if (sw_csum & CSUM_DELAY_IP) 1189 mhip->ip_sum = in_cksum(m, mhlen); 1190 *mnext = m; 1191 mnext = &m->m_nextpkt; 1192 } 1193 ipstat.ips_ofragments += nfrags; 1194 1195 /* set first marker for fragment chain */ 1196 m0->m_flags |= M_FIRSTFRAG | M_FRAG; 1197 m0->m_pkthdr.csum_data = nfrags; 1198 1199 /* 1200 * Update first fragment by trimming what's been copied out 1201 * and updating header. 1202 */ 1203 m_adj(m0, hlen + firstlen - ip->ip_len); 1204 m0->m_pkthdr.len = hlen + firstlen; 1205 ip->ip_len = htons((u_short)m0->m_pkthdr.len); 1206 ip->ip_off |= IP_MF; 1207 ip->ip_off = htons(ip->ip_off); 1208 ip->ip_sum = 0; 1209 if (sw_csum & CSUM_DELAY_IP) 1210 ip->ip_sum = in_cksum(m0, hlen); 1211 1212 done: 1213 *m_frag = m0; 1214 return error; 1215 } 1216 1217 void 1218 in_delayed_cksum(struct mbuf *m) 1219 { 1220 struct ip *ip; 1221 u_short csum, offset; 1222 1223 ip = mtod(m, struct ip *); 1224 offset = IP_VHL_HL(ip->ip_vhl) << 2 ; 1225 csum = in_cksum_skip(m, ip->ip_len, offset); 1226 if (m->m_pkthdr.csum_flags & CSUM_UDP && csum == 0) 1227 csum = 0xffff; 1228 offset += m->m_pkthdr.csum_data; /* checksum offset */ 1229 1230 if (offset + sizeof(u_short) > m->m_len) { 1231 kprintf("delayed m_pullup, m->len: %d off: %d p: %d\n", 1232 m->m_len, offset, ip->ip_p); 1233 /* 1234 * XXX 1235 * this shouldn't happen, but if it does, the 1236 * correct behavior may be to insert the checksum 1237 * in the existing chain instead of rearranging it. 1238 */ 1239 m = m_pullup(m, offset + sizeof(u_short)); 1240 } 1241 *(u_short *)(m->m_data + offset) = csum; 1242 } 1243 1244 /* 1245 * Insert IP options into preformed packet. 1246 * Adjust IP destination as required for IP source routing, 1247 * as indicated by a non-zero in_addr at the start of the options. 1248 * 1249 * XXX This routine assumes that the packet has no options in place. 1250 */ 1251 static struct mbuf * 1252 ip_insertoptions(struct mbuf *m, struct mbuf *opt, int *phlen) 1253 { 1254 struct ipoption *p = mtod(opt, struct ipoption *); 1255 struct mbuf *n; 1256 struct ip *ip = mtod(m, struct ip *); 1257 unsigned optlen; 1258 1259 optlen = opt->m_len - sizeof p->ipopt_dst; 1260 if (optlen + (u_short)ip->ip_len > IP_MAXPACKET) { 1261 *phlen = 0; 1262 return (m); /* XXX should fail */ 1263 } 1264 if (p->ipopt_dst.s_addr) 1265 ip->ip_dst = p->ipopt_dst; 1266 if (m->m_flags & M_EXT || m->m_data - optlen < m->m_pktdat) { 1267 MGETHDR(n, MB_DONTWAIT, MT_HEADER); 1268 if (n == NULL) { 1269 *phlen = 0; 1270 return (m); 1271 } 1272 n->m_pkthdr.rcvif = NULL; 1273 n->m_pkthdr.len = m->m_pkthdr.len + optlen; 1274 m->m_len -= sizeof(struct ip); 1275 m->m_data += sizeof(struct ip); 1276 n->m_next = m; 1277 m = n; 1278 m->m_len = optlen + sizeof(struct ip); 1279 m->m_data += max_linkhdr; 1280 memcpy(mtod(m, void *), ip, sizeof(struct ip)); 1281 } else { 1282 m->m_data -= optlen; 1283 m->m_len += optlen; 1284 m->m_pkthdr.len += optlen; 1285 ovbcopy(ip, mtod(m, caddr_t), sizeof(struct ip)); 1286 } 1287 ip = mtod(m, struct ip *); 1288 bcopy(p->ipopt_list, ip + 1, optlen); 1289 *phlen = sizeof(struct ip) + optlen; 1290 ip->ip_vhl = IP_MAKE_VHL(IPVERSION, *phlen >> 2); 1291 ip->ip_len += optlen; 1292 return (m); 1293 } 1294 1295 /* 1296 * Copy options from ip to jp, 1297 * omitting those not copied during fragmentation. 1298 */ 1299 int 1300 ip_optcopy(struct ip *ip, struct ip *jp) 1301 { 1302 u_char *cp, *dp; 1303 int opt, optlen, cnt; 1304 1305 cp = (u_char *)(ip + 1); 1306 dp = (u_char *)(jp + 1); 1307 cnt = (IP_VHL_HL(ip->ip_vhl) << 2) - sizeof(struct ip); 1308 for (; cnt > 0; cnt -= optlen, cp += optlen) { 1309 opt = cp[0]; 1310 if (opt == IPOPT_EOL) 1311 break; 1312 if (opt == IPOPT_NOP) { 1313 /* Preserve for IP mcast tunnel's LSRR alignment. */ 1314 *dp++ = IPOPT_NOP; 1315 optlen = 1; 1316 continue; 1317 } 1318 1319 KASSERT(cnt >= IPOPT_OLEN + sizeof *cp, 1320 ("ip_optcopy: malformed ipv4 option")); 1321 optlen = cp[IPOPT_OLEN]; 1322 KASSERT(optlen >= IPOPT_OLEN + sizeof *cp && optlen <= cnt, 1323 ("ip_optcopy: malformed ipv4 option")); 1324 1325 /* bogus lengths should have been caught by ip_dooptions */ 1326 if (optlen > cnt) 1327 optlen = cnt; 1328 if (IPOPT_COPIED(opt)) { 1329 bcopy(cp, dp, optlen); 1330 dp += optlen; 1331 } 1332 } 1333 for (optlen = dp - (u_char *)(jp+1); optlen & 0x3; optlen++) 1334 *dp++ = IPOPT_EOL; 1335 return (optlen); 1336 } 1337 1338 /* 1339 * IP socket option processing. 1340 */ 1341 void 1342 ip_ctloutput(netmsg_t msg) 1343 { 1344 struct socket *so = msg->base.nm_so; 1345 struct sockopt *sopt = msg->ctloutput.nm_sopt; 1346 struct inpcb *inp = so->so_pcb; 1347 int error, optval; 1348 1349 error = optval = 0; 1350 if (sopt->sopt_level != IPPROTO_IP) { 1351 error = EINVAL; 1352 goto done; 1353 } 1354 1355 switch (sopt->sopt_dir) { 1356 case SOPT_SET: 1357 switch (sopt->sopt_name) { 1358 case IP_OPTIONS: 1359 #ifdef notyet 1360 case IP_RETOPTS: 1361 #endif 1362 { 1363 struct mbuf *m; 1364 if (sopt->sopt_valsize > MLEN) { 1365 error = EMSGSIZE; 1366 break; 1367 } 1368 MGET(m, sopt->sopt_td ? MB_WAIT : MB_DONTWAIT, MT_HEADER); 1369 if (m == NULL) { 1370 error = ENOBUFS; 1371 break; 1372 } 1373 m->m_len = sopt->sopt_valsize; 1374 error = soopt_to_kbuf(sopt, mtod(m, void *), m->m_len, 1375 m->m_len); 1376 error = ip_pcbopts(sopt->sopt_name, 1377 &inp->inp_options, m); 1378 goto done; 1379 } 1380 1381 case IP_TOS: 1382 case IP_TTL: 1383 case IP_MINTTL: 1384 case IP_RECVOPTS: 1385 case IP_RECVRETOPTS: 1386 case IP_RECVDSTADDR: 1387 case IP_RECVIF: 1388 case IP_RECVTTL: 1389 case IP_FAITH: 1390 error = soopt_to_kbuf(sopt, &optval, sizeof optval, 1391 sizeof optval); 1392 if (error) 1393 break; 1394 switch (sopt->sopt_name) { 1395 case IP_TOS: 1396 inp->inp_ip_tos = optval; 1397 break; 1398 1399 case IP_TTL: 1400 inp->inp_ip_ttl = optval; 1401 break; 1402 case IP_MINTTL: 1403 if (optval >= 0 && optval <= MAXTTL) 1404 inp->inp_ip_minttl = optval; 1405 else 1406 error = EINVAL; 1407 break; 1408 #define OPTSET(bit) \ 1409 if (optval) \ 1410 inp->inp_flags |= bit; \ 1411 else \ 1412 inp->inp_flags &= ~bit; 1413 1414 case IP_RECVOPTS: 1415 OPTSET(INP_RECVOPTS); 1416 break; 1417 1418 case IP_RECVRETOPTS: 1419 OPTSET(INP_RECVRETOPTS); 1420 break; 1421 1422 case IP_RECVDSTADDR: 1423 OPTSET(INP_RECVDSTADDR); 1424 break; 1425 1426 case IP_RECVIF: 1427 OPTSET(INP_RECVIF); 1428 break; 1429 1430 case IP_RECVTTL: 1431 OPTSET(INP_RECVTTL); 1432 break; 1433 1434 case IP_FAITH: 1435 OPTSET(INP_FAITH); 1436 break; 1437 } 1438 break; 1439 #undef OPTSET 1440 1441 case IP_MULTICAST_IF: 1442 case IP_MULTICAST_VIF: 1443 case IP_MULTICAST_TTL: 1444 case IP_MULTICAST_LOOP: 1445 case IP_ADD_MEMBERSHIP: 1446 case IP_DROP_MEMBERSHIP: 1447 error = ip_setmoptions(sopt, &inp->inp_moptions); 1448 break; 1449 1450 case IP_PORTRANGE: 1451 error = soopt_to_kbuf(sopt, &optval, sizeof optval, 1452 sizeof optval); 1453 if (error) 1454 break; 1455 1456 switch (optval) { 1457 case IP_PORTRANGE_DEFAULT: 1458 inp->inp_flags &= ~(INP_LOWPORT); 1459 inp->inp_flags &= ~(INP_HIGHPORT); 1460 break; 1461 1462 case IP_PORTRANGE_HIGH: 1463 inp->inp_flags &= ~(INP_LOWPORT); 1464 inp->inp_flags |= INP_HIGHPORT; 1465 break; 1466 1467 case IP_PORTRANGE_LOW: 1468 inp->inp_flags &= ~(INP_HIGHPORT); 1469 inp->inp_flags |= INP_LOWPORT; 1470 break; 1471 1472 default: 1473 error = EINVAL; 1474 break; 1475 } 1476 break; 1477 1478 #if defined(IPSEC) || defined(FAST_IPSEC) 1479 case IP_IPSEC_POLICY: 1480 { 1481 caddr_t req; 1482 size_t len = 0; 1483 int priv; 1484 struct mbuf *m; 1485 int optname; 1486 1487 if ((error = soopt_getm(sopt, &m)) != 0) /* XXX */ 1488 break; 1489 soopt_to_mbuf(sopt, m); 1490 priv = (sopt->sopt_td != NULL && 1491 priv_check(sopt->sopt_td, PRIV_ROOT) != 0) ? 0 : 1; 1492 req = mtod(m, caddr_t); 1493 len = m->m_len; 1494 optname = sopt->sopt_name; 1495 error = ipsec4_set_policy(inp, optname, req, len, priv); 1496 m_freem(m); 1497 break; 1498 } 1499 #endif /*IPSEC*/ 1500 1501 default: 1502 error = ENOPROTOOPT; 1503 break; 1504 } 1505 break; 1506 1507 case SOPT_GET: 1508 switch (sopt->sopt_name) { 1509 case IP_OPTIONS: 1510 case IP_RETOPTS: 1511 if (inp->inp_options) 1512 soopt_from_kbuf(sopt, mtod(inp->inp_options, 1513 char *), 1514 inp->inp_options->m_len); 1515 else 1516 sopt->sopt_valsize = 0; 1517 break; 1518 1519 case IP_TOS: 1520 case IP_TTL: 1521 case IP_MINTTL: 1522 case IP_RECVOPTS: 1523 case IP_RECVRETOPTS: 1524 case IP_RECVDSTADDR: 1525 case IP_RECVTTL: 1526 case IP_RECVIF: 1527 case IP_PORTRANGE: 1528 case IP_FAITH: 1529 switch (sopt->sopt_name) { 1530 1531 case IP_TOS: 1532 optval = inp->inp_ip_tos; 1533 break; 1534 1535 case IP_TTL: 1536 optval = inp->inp_ip_ttl; 1537 break; 1538 case IP_MINTTL: 1539 optval = inp->inp_ip_minttl; 1540 break; 1541 1542 #define OPTBIT(bit) (inp->inp_flags & bit ? 1 : 0) 1543 1544 case IP_RECVOPTS: 1545 optval = OPTBIT(INP_RECVOPTS); 1546 break; 1547 1548 case IP_RECVRETOPTS: 1549 optval = OPTBIT(INP_RECVRETOPTS); 1550 break; 1551 1552 case IP_RECVDSTADDR: 1553 optval = OPTBIT(INP_RECVDSTADDR); 1554 break; 1555 1556 case IP_RECVTTL: 1557 optval = OPTBIT(INP_RECVTTL); 1558 break; 1559 1560 case IP_RECVIF: 1561 optval = OPTBIT(INP_RECVIF); 1562 break; 1563 1564 case IP_PORTRANGE: 1565 if (inp->inp_flags & INP_HIGHPORT) 1566 optval = IP_PORTRANGE_HIGH; 1567 else if (inp->inp_flags & INP_LOWPORT) 1568 optval = IP_PORTRANGE_LOW; 1569 else 1570 optval = 0; 1571 break; 1572 1573 case IP_FAITH: 1574 optval = OPTBIT(INP_FAITH); 1575 break; 1576 } 1577 soopt_from_kbuf(sopt, &optval, sizeof optval); 1578 break; 1579 1580 case IP_MULTICAST_IF: 1581 case IP_MULTICAST_VIF: 1582 case IP_MULTICAST_TTL: 1583 case IP_MULTICAST_LOOP: 1584 case IP_ADD_MEMBERSHIP: 1585 case IP_DROP_MEMBERSHIP: 1586 error = ip_getmoptions(sopt, inp->inp_moptions); 1587 break; 1588 1589 #if defined(IPSEC) || defined(FAST_IPSEC) 1590 case IP_IPSEC_POLICY: 1591 { 1592 struct mbuf *m = NULL; 1593 caddr_t req = NULL; 1594 size_t len = 0; 1595 1596 if (m != NULL) { 1597 req = mtod(m, caddr_t); 1598 len = m->m_len; 1599 } 1600 error = ipsec4_get_policy(so->so_pcb, req, len, &m); 1601 if (error == 0) 1602 error = soopt_from_mbuf(sopt, m); /* XXX */ 1603 if (error == 0) 1604 m_freem(m); 1605 break; 1606 } 1607 #endif /*IPSEC*/ 1608 1609 default: 1610 error = ENOPROTOOPT; 1611 break; 1612 } 1613 break; 1614 } 1615 done: 1616 lwkt_replymsg(&msg->lmsg, error); 1617 } 1618 1619 /* 1620 * Set up IP options in pcb for insertion in output packets. 1621 * Store in mbuf with pointer in pcbopt, adding pseudo-option 1622 * with destination address if source routed. 1623 */ 1624 static int 1625 ip_pcbopts(int optname, struct mbuf **pcbopt, struct mbuf *m) 1626 { 1627 int cnt, optlen; 1628 u_char *cp; 1629 u_char opt; 1630 1631 /* turn off any old options */ 1632 if (*pcbopt) 1633 m_free(*pcbopt); 1634 *pcbopt = 0; 1635 if (m == NULL || m->m_len == 0) { 1636 /* 1637 * Only turning off any previous options. 1638 */ 1639 if (m != NULL) 1640 m_free(m); 1641 return (0); 1642 } 1643 1644 if (m->m_len % sizeof(int32_t)) 1645 goto bad; 1646 /* 1647 * IP first-hop destination address will be stored before 1648 * actual options; move other options back 1649 * and clear it when none present. 1650 */ 1651 if (m->m_data + m->m_len + sizeof(struct in_addr) >= &m->m_dat[MLEN]) 1652 goto bad; 1653 cnt = m->m_len; 1654 m->m_len += sizeof(struct in_addr); 1655 cp = mtod(m, u_char *) + sizeof(struct in_addr); 1656 ovbcopy(mtod(m, caddr_t), cp, cnt); 1657 bzero(mtod(m, caddr_t), sizeof(struct in_addr)); 1658 1659 for (; cnt > 0; cnt -= optlen, cp += optlen) { 1660 opt = cp[IPOPT_OPTVAL]; 1661 if (opt == IPOPT_EOL) 1662 break; 1663 if (opt == IPOPT_NOP) 1664 optlen = 1; 1665 else { 1666 if (cnt < IPOPT_OLEN + sizeof *cp) 1667 goto bad; 1668 optlen = cp[IPOPT_OLEN]; 1669 if (optlen < IPOPT_OLEN + sizeof *cp || optlen > cnt) 1670 goto bad; 1671 } 1672 switch (opt) { 1673 1674 default: 1675 break; 1676 1677 case IPOPT_LSRR: 1678 case IPOPT_SSRR: 1679 /* 1680 * user process specifies route as: 1681 * ->A->B->C->D 1682 * D must be our final destination (but we can't 1683 * check that since we may not have connected yet). 1684 * A is first hop destination, which doesn't appear in 1685 * actual IP option, but is stored before the options. 1686 */ 1687 if (optlen < IPOPT_MINOFF - 1 + sizeof(struct in_addr)) 1688 goto bad; 1689 m->m_len -= sizeof(struct in_addr); 1690 cnt -= sizeof(struct in_addr); 1691 optlen -= sizeof(struct in_addr); 1692 cp[IPOPT_OLEN] = optlen; 1693 /* 1694 * Move first hop before start of options. 1695 */ 1696 bcopy(&cp[IPOPT_OFFSET+1], mtod(m, caddr_t), 1697 sizeof(struct in_addr)); 1698 /* 1699 * Then copy rest of options back 1700 * to close up the deleted entry. 1701 */ 1702 ovbcopy(&cp[IPOPT_OFFSET+1] + sizeof(struct in_addr), 1703 &cp[IPOPT_OFFSET+1], 1704 cnt - (IPOPT_MINOFF - 1)); 1705 break; 1706 } 1707 } 1708 if (m->m_len > MAX_IPOPTLEN + sizeof(struct in_addr)) 1709 goto bad; 1710 *pcbopt = m; 1711 return (0); 1712 1713 bad: 1714 m_free(m); 1715 return (EINVAL); 1716 } 1717 1718 /* 1719 * XXX 1720 * The whole multicast option thing needs to be re-thought. 1721 * Several of these options are equally applicable to non-multicast 1722 * transmission, and one (IP_MULTICAST_TTL) totally duplicates a 1723 * standard option (IP_TTL). 1724 */ 1725 1726 /* 1727 * following RFC1724 section 3.3, 0.0.0.0/8 is interpreted as interface index. 1728 */ 1729 static struct ifnet * 1730 ip_multicast_if(struct in_addr *a, int *ifindexp) 1731 { 1732 int ifindex; 1733 struct ifnet *ifp; 1734 1735 if (ifindexp) 1736 *ifindexp = 0; 1737 if (ntohl(a->s_addr) >> 24 == 0) { 1738 ifindex = ntohl(a->s_addr) & 0xffffff; 1739 if (ifindex < 0 || if_index < ifindex) 1740 return NULL; 1741 ifp = ifindex2ifnet[ifindex]; 1742 if (ifindexp) 1743 *ifindexp = ifindex; 1744 } else { 1745 ifp = INADDR_TO_IFP(a); 1746 } 1747 return ifp; 1748 } 1749 1750 /* 1751 * Set the IP multicast options in response to user setsockopt(). 1752 */ 1753 static int 1754 ip_setmoptions(struct sockopt *sopt, struct ip_moptions **imop) 1755 { 1756 int error = 0; 1757 int i; 1758 struct in_addr addr; 1759 struct ip_mreq mreq; 1760 struct ifnet *ifp; 1761 struct ip_moptions *imo = *imop; 1762 int ifindex; 1763 1764 if (imo == NULL) { 1765 /* 1766 * No multicast option buffer attached to the pcb; 1767 * allocate one and initialize to default values. 1768 */ 1769 imo = kmalloc(sizeof *imo, M_IPMOPTS, M_WAITOK); 1770 1771 *imop = imo; 1772 imo->imo_multicast_ifp = NULL; 1773 imo->imo_multicast_addr.s_addr = INADDR_ANY; 1774 imo->imo_multicast_vif = -1; 1775 imo->imo_multicast_ttl = IP_DEFAULT_MULTICAST_TTL; 1776 imo->imo_multicast_loop = IP_DEFAULT_MULTICAST_LOOP; 1777 imo->imo_num_memberships = 0; 1778 } 1779 switch (sopt->sopt_name) { 1780 /* store an index number for the vif you wanna use in the send */ 1781 case IP_MULTICAST_VIF: 1782 if (legal_vif_num == 0) { 1783 error = EOPNOTSUPP; 1784 break; 1785 } 1786 error = soopt_to_kbuf(sopt, &i, sizeof i, sizeof i); 1787 if (error) 1788 break; 1789 if (!legal_vif_num(i) && (i != -1)) { 1790 error = EINVAL; 1791 break; 1792 } 1793 imo->imo_multicast_vif = i; 1794 break; 1795 1796 case IP_MULTICAST_IF: 1797 /* 1798 * Select the interface for outgoing multicast packets. 1799 */ 1800 error = soopt_to_kbuf(sopt, &addr, sizeof addr, sizeof addr); 1801 if (error) 1802 break; 1803 1804 /* 1805 * INADDR_ANY is used to remove a previous selection. 1806 * When no interface is selected, a default one is 1807 * chosen every time a multicast packet is sent. 1808 */ 1809 if (addr.s_addr == INADDR_ANY) { 1810 imo->imo_multicast_ifp = NULL; 1811 break; 1812 } 1813 /* 1814 * The selected interface is identified by its local 1815 * IP address. Find the interface and confirm that 1816 * it supports multicasting. 1817 */ 1818 crit_enter(); 1819 ifp = ip_multicast_if(&addr, &ifindex); 1820 if (ifp == NULL || !(ifp->if_flags & IFF_MULTICAST)) { 1821 crit_exit(); 1822 error = EADDRNOTAVAIL; 1823 break; 1824 } 1825 imo->imo_multicast_ifp = ifp; 1826 if (ifindex) 1827 imo->imo_multicast_addr = addr; 1828 else 1829 imo->imo_multicast_addr.s_addr = INADDR_ANY; 1830 crit_exit(); 1831 break; 1832 1833 case IP_MULTICAST_TTL: 1834 /* 1835 * Set the IP time-to-live for outgoing multicast packets. 1836 * The original multicast API required a char argument, 1837 * which is inconsistent with the rest of the socket API. 1838 * We allow either a char or an int. 1839 */ 1840 if (sopt->sopt_valsize == 1) { 1841 u_char ttl; 1842 error = soopt_to_kbuf(sopt, &ttl, 1, 1); 1843 if (error) 1844 break; 1845 imo->imo_multicast_ttl = ttl; 1846 } else { 1847 u_int ttl; 1848 error = soopt_to_kbuf(sopt, &ttl, sizeof ttl, sizeof ttl); 1849 if (error) 1850 break; 1851 if (ttl > 255) 1852 error = EINVAL; 1853 else 1854 imo->imo_multicast_ttl = ttl; 1855 } 1856 break; 1857 1858 case IP_MULTICAST_LOOP: 1859 /* 1860 * Set the loopback flag for outgoing multicast packets. 1861 * Must be zero or one. The original multicast API required a 1862 * char argument, which is inconsistent with the rest 1863 * of the socket API. We allow either a char or an int. 1864 */ 1865 if (sopt->sopt_valsize == 1) { 1866 u_char loop; 1867 1868 error = soopt_to_kbuf(sopt, &loop, 1, 1); 1869 if (error) 1870 break; 1871 imo->imo_multicast_loop = !!loop; 1872 } else { 1873 u_int loop; 1874 1875 error = soopt_to_kbuf(sopt, &loop, sizeof loop, 1876 sizeof loop); 1877 if (error) 1878 break; 1879 imo->imo_multicast_loop = !!loop; 1880 } 1881 break; 1882 1883 case IP_ADD_MEMBERSHIP: 1884 /* 1885 * Add a multicast group membership. 1886 * Group must be a valid IP multicast address. 1887 */ 1888 error = soopt_to_kbuf(sopt, &mreq, sizeof mreq, sizeof mreq); 1889 if (error) 1890 break; 1891 1892 if (!IN_MULTICAST(ntohl(mreq.imr_multiaddr.s_addr))) { 1893 error = EINVAL; 1894 break; 1895 } 1896 crit_enter(); 1897 /* 1898 * If no interface address was provided, use the interface of 1899 * the route to the given multicast address. 1900 */ 1901 if (mreq.imr_interface.s_addr == INADDR_ANY) { 1902 struct sockaddr_in dst; 1903 struct rtentry *rt; 1904 1905 bzero(&dst, sizeof(struct sockaddr_in)); 1906 dst.sin_len = sizeof(struct sockaddr_in); 1907 dst.sin_family = AF_INET; 1908 dst.sin_addr = mreq.imr_multiaddr; 1909 rt = rtlookup((struct sockaddr *)&dst); 1910 if (rt == NULL) { 1911 error = EADDRNOTAVAIL; 1912 crit_exit(); 1913 break; 1914 } 1915 --rt->rt_refcnt; 1916 ifp = rt->rt_ifp; 1917 } else { 1918 ifp = ip_multicast_if(&mreq.imr_interface, NULL); 1919 } 1920 1921 /* 1922 * See if we found an interface, and confirm that it 1923 * supports multicast. 1924 */ 1925 if (ifp == NULL || !(ifp->if_flags & IFF_MULTICAST)) { 1926 error = EADDRNOTAVAIL; 1927 crit_exit(); 1928 break; 1929 } 1930 /* 1931 * See if the membership already exists or if all the 1932 * membership slots are full. 1933 */ 1934 for (i = 0; i < imo->imo_num_memberships; ++i) { 1935 if (imo->imo_membership[i]->inm_ifp == ifp && 1936 imo->imo_membership[i]->inm_addr.s_addr 1937 == mreq.imr_multiaddr.s_addr) 1938 break; 1939 } 1940 if (i < imo->imo_num_memberships) { 1941 error = EADDRINUSE; 1942 crit_exit(); 1943 break; 1944 } 1945 if (i == IP_MAX_MEMBERSHIPS) { 1946 error = ETOOMANYREFS; 1947 crit_exit(); 1948 break; 1949 } 1950 /* 1951 * Everything looks good; add a new record to the multicast 1952 * address list for the given interface. 1953 */ 1954 if ((imo->imo_membership[i] = 1955 in_addmulti(&mreq.imr_multiaddr, ifp)) == NULL) { 1956 error = ENOBUFS; 1957 crit_exit(); 1958 break; 1959 } 1960 ++imo->imo_num_memberships; 1961 crit_exit(); 1962 break; 1963 1964 case IP_DROP_MEMBERSHIP: 1965 /* 1966 * Drop a multicast group membership. 1967 * Group must be a valid IP multicast address. 1968 */ 1969 error = soopt_to_kbuf(sopt, &mreq, sizeof mreq, sizeof mreq); 1970 if (error) 1971 break; 1972 1973 if (!IN_MULTICAST(ntohl(mreq.imr_multiaddr.s_addr))) { 1974 error = EINVAL; 1975 break; 1976 } 1977 1978 crit_enter(); 1979 /* 1980 * If an interface address was specified, get a pointer 1981 * to its ifnet structure. 1982 */ 1983 if (mreq.imr_interface.s_addr == INADDR_ANY) 1984 ifp = NULL; 1985 else { 1986 ifp = ip_multicast_if(&mreq.imr_interface, NULL); 1987 if (ifp == NULL) { 1988 error = EADDRNOTAVAIL; 1989 crit_exit(); 1990 break; 1991 } 1992 } 1993 /* 1994 * Find the membership in the membership array. 1995 */ 1996 for (i = 0; i < imo->imo_num_memberships; ++i) { 1997 if ((ifp == NULL || 1998 imo->imo_membership[i]->inm_ifp == ifp) && 1999 imo->imo_membership[i]->inm_addr.s_addr == 2000 mreq.imr_multiaddr.s_addr) 2001 break; 2002 } 2003 if (i == imo->imo_num_memberships) { 2004 error = EADDRNOTAVAIL; 2005 crit_exit(); 2006 break; 2007 } 2008 /* 2009 * Give up the multicast address record to which the 2010 * membership points. 2011 */ 2012 in_delmulti(imo->imo_membership[i]); 2013 /* 2014 * Remove the gap in the membership array. 2015 */ 2016 for (++i; i < imo->imo_num_memberships; ++i) 2017 imo->imo_membership[i-1] = imo->imo_membership[i]; 2018 --imo->imo_num_memberships; 2019 crit_exit(); 2020 break; 2021 2022 default: 2023 error = EOPNOTSUPP; 2024 break; 2025 } 2026 2027 /* 2028 * If all options have default values, no need to keep the mbuf. 2029 */ 2030 if (imo->imo_multicast_ifp == NULL && 2031 imo->imo_multicast_vif == -1 && 2032 imo->imo_multicast_ttl == IP_DEFAULT_MULTICAST_TTL && 2033 imo->imo_multicast_loop == IP_DEFAULT_MULTICAST_LOOP && 2034 imo->imo_num_memberships == 0) { 2035 kfree(*imop, M_IPMOPTS); 2036 *imop = NULL; 2037 } 2038 2039 return (error); 2040 } 2041 2042 /* 2043 * Return the IP multicast options in response to user getsockopt(). 2044 */ 2045 static int 2046 ip_getmoptions(struct sockopt *sopt, struct ip_moptions *imo) 2047 { 2048 struct in_addr addr; 2049 struct in_ifaddr *ia; 2050 int error, optval; 2051 u_char coptval; 2052 2053 error = 0; 2054 switch (sopt->sopt_name) { 2055 case IP_MULTICAST_VIF: 2056 if (imo != NULL) 2057 optval = imo->imo_multicast_vif; 2058 else 2059 optval = -1; 2060 soopt_from_kbuf(sopt, &optval, sizeof optval); 2061 break; 2062 2063 case IP_MULTICAST_IF: 2064 if (imo == NULL || imo->imo_multicast_ifp == NULL) 2065 addr.s_addr = INADDR_ANY; 2066 else if (imo->imo_multicast_addr.s_addr) { 2067 /* return the value user has set */ 2068 addr = imo->imo_multicast_addr; 2069 } else { 2070 ia = IFP_TO_IA(imo->imo_multicast_ifp); 2071 addr.s_addr = (ia == NULL) ? INADDR_ANY 2072 : IA_SIN(ia)->sin_addr.s_addr; 2073 } 2074 soopt_from_kbuf(sopt, &addr, sizeof addr); 2075 break; 2076 2077 case IP_MULTICAST_TTL: 2078 if (imo == NULL) 2079 optval = coptval = IP_DEFAULT_MULTICAST_TTL; 2080 else 2081 optval = coptval = imo->imo_multicast_ttl; 2082 if (sopt->sopt_valsize == 1) 2083 soopt_from_kbuf(sopt, &coptval, 1); 2084 else 2085 soopt_from_kbuf(sopt, &optval, sizeof optval); 2086 break; 2087 2088 case IP_MULTICAST_LOOP: 2089 if (imo == NULL) 2090 optval = coptval = IP_DEFAULT_MULTICAST_LOOP; 2091 else 2092 optval = coptval = imo->imo_multicast_loop; 2093 if (sopt->sopt_valsize == 1) 2094 soopt_from_kbuf(sopt, &coptval, 1); 2095 else 2096 soopt_from_kbuf(sopt, &optval, sizeof optval); 2097 break; 2098 2099 default: 2100 error = ENOPROTOOPT; 2101 break; 2102 } 2103 return (error); 2104 } 2105 2106 /* 2107 * Discard the IP multicast options. 2108 */ 2109 void 2110 ip_freemoptions(struct ip_moptions *imo) 2111 { 2112 int i; 2113 2114 if (imo != NULL) { 2115 for (i = 0; i < imo->imo_num_memberships; ++i) 2116 in_delmulti(imo->imo_membership[i]); 2117 kfree(imo, M_IPMOPTS); 2118 } 2119 } 2120 2121 /* 2122 * Routine called from ip_output() to loop back a copy of an IP multicast 2123 * packet to the input queue of a specified interface. Note that this 2124 * calls the output routine of the loopback "driver", but with an interface 2125 * pointer that might NOT be a loopback interface -- evil, but easier than 2126 * replicating that code here. 2127 */ 2128 static void 2129 ip_mloopback(struct ifnet *ifp, struct mbuf *m, struct sockaddr_in *dst, 2130 int hlen) 2131 { 2132 struct ip *ip; 2133 struct mbuf *copym; 2134 2135 copym = m_copypacket(m, MB_DONTWAIT); 2136 if (copym != NULL && (copym->m_flags & M_EXT || copym->m_len < hlen)) 2137 copym = m_pullup(copym, hlen); 2138 if (copym != NULL) { 2139 /* 2140 * if the checksum hasn't been computed, mark it as valid 2141 */ 2142 if (copym->m_pkthdr.csum_flags & CSUM_DELAY_DATA) { 2143 in_delayed_cksum(copym); 2144 copym->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA; 2145 copym->m_pkthdr.csum_flags |= 2146 CSUM_DATA_VALID | CSUM_PSEUDO_HDR; 2147 copym->m_pkthdr.csum_data = 0xffff; 2148 } 2149 /* 2150 * We don't bother to fragment if the IP length is greater 2151 * than the interface's MTU. Can this possibly matter? 2152 */ 2153 ip = mtod(copym, struct ip *); 2154 ip->ip_len = htons(ip->ip_len); 2155 ip->ip_off = htons(ip->ip_off); 2156 ip->ip_sum = 0; 2157 if (ip->ip_vhl == IP_VHL_BORING) { 2158 ip->ip_sum = in_cksum_hdr(ip); 2159 } else { 2160 ip->ip_sum = in_cksum(copym, hlen); 2161 } 2162 /* 2163 * NB: 2164 * It's not clear whether there are any lingering 2165 * reentrancy problems in other areas which might 2166 * be exposed by using ip_input directly (in 2167 * particular, everything which modifies the packet 2168 * in-place). Yet another option is using the 2169 * protosw directly to deliver the looped back 2170 * packet. For the moment, we'll err on the side 2171 * of safety by using if_simloop(). 2172 */ 2173 #if 1 /* XXX */ 2174 if (dst->sin_family != AF_INET) { 2175 kprintf("ip_mloopback: bad address family %d\n", 2176 dst->sin_family); 2177 dst->sin_family = AF_INET; 2178 } 2179 #endif 2180 get_mplock(); /* is if_simloop() mpsafe yet? */ 2181 if_simloop(ifp, copym, dst->sin_family, 0); 2182 rel_mplock(); 2183 } 2184 } 2185