1 /* $NetBSD: ip_output.c,v 1.69 2000/03/01 12:49:35 itojun Exp $ */ 2 3 /* 4 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the project nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 /*- 33 * Copyright (c) 1998 The NetBSD Foundation, Inc. 34 * All rights reserved. 35 * 36 * This code is derived from software contributed to The NetBSD Foundation 37 * by Public Access Networks Corporation ("Panix"). It was developed under 38 * contract to Panix by Eric Haszlakiewicz and Thor Lancelot Simon. 39 * 40 * Redistribution and use in source and binary forms, with or without 41 * modification, are permitted provided that the following conditions 42 * are met: 43 * 1. Redistributions of source code must retain the above copyright 44 * notice, this list of conditions and the following disclaimer. 45 * 2. Redistributions in binary form must reproduce the above copyright 46 * notice, this list of conditions and the following disclaimer in the 47 * documentation and/or other materials provided with the distribution. 48 * 3. All advertising materials mentioning features or use of this software 49 * must display the following acknowledgement: 50 * This product includes software developed by the NetBSD 51 * Foundation, Inc. and its contributors. 52 * 4. Neither the name of The NetBSD Foundation nor the names of its 53 * contributors may be used to endorse or promote products derived 54 * from this software without specific prior written permission. 55 * 56 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 57 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 58 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 59 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 60 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 61 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 62 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 63 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 64 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 65 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 66 * POSSIBILITY OF SUCH DAMAGE. 67 */ 68 69 /* 70 * Copyright (c) 1982, 1986, 1988, 1990, 1993 71 * The Regents of the University of California. All rights reserved. 72 * 73 * Redistribution and use in source and binary forms, with or without 74 * modification, are permitted provided that the following conditions 75 * are met: 76 * 1. Redistributions of source code must retain the above copyright 77 * notice, this list of conditions and the following disclaimer. 78 * 2. Redistributions in binary form must reproduce the above copyright 79 * notice, this list of conditions and the following disclaimer in the 80 * documentation and/or other materials provided with the distribution. 81 * 3. All advertising materials mentioning features or use of this software 82 * must display the following acknowledgement: 83 * This product includes software developed by the University of 84 * California, Berkeley and its contributors. 85 * 4. Neither the name of the University nor the names of its contributors 86 * may be used to endorse or promote products derived from this software 87 * without specific prior written permission. 88 * 89 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 90 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 91 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 92 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 93 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 94 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 95 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 96 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 97 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 98 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 99 * SUCH DAMAGE. 100 * 101 * @(#)ip_output.c 8.3 (Berkeley) 1/21/94 102 */ 103 104 #include "opt_pfil_hooks.h" 105 #include "opt_ipsec.h" 106 #include "opt_mrouting.h" 107 108 #include <sys/param.h> 109 #include <sys/malloc.h> 110 #include <sys/mbuf.h> 111 #include <sys/errno.h> 112 #include <sys/protosw.h> 113 #include <sys/socket.h> 114 #include <sys/socketvar.h> 115 #include <sys/systm.h> 116 117 #include <vm/vm.h> 118 #include <sys/proc.h> 119 120 #include <net/if.h> 121 #include <net/route.h> 122 #include <net/pfil.h> 123 124 #include <netinet/in.h> 125 #include <netinet/in_systm.h> 126 #include <netinet/ip.h> 127 #include <netinet/in_pcb.h> 128 #include <netinet/in_var.h> 129 #include <netinet/ip_var.h> 130 131 #ifdef __vax__ 132 #include <machine/mtpr.h> 133 #endif 134 135 #include <machine/stdarg.h> 136 137 #ifdef IPSEC 138 #include <netinet6/ipsec.h> 139 #include <netkey/key.h> 140 #include <netkey/key_debug.h> 141 #endif /*IPSEC*/ 142 143 static struct mbuf *ip_insertoptions __P((struct mbuf *, struct mbuf *, int *)); 144 static void ip_mloopback 145 __P((struct ifnet *, struct mbuf *, struct sockaddr_in *)); 146 147 /* 148 * IP output. The packet in mbuf chain m contains a skeletal IP 149 * header (with len, off, ttl, proto, tos, src, dst). 150 * The mbuf chain containing the packet will be freed. 151 * The mbuf opt, if present, will not be freed. 152 */ 153 int 154 #if __STDC__ 155 ip_output(struct mbuf *m0, ...) 156 #else 157 ip_output(m0, va_alist) 158 struct mbuf *m0; 159 va_dcl 160 #endif 161 { 162 register struct ip *ip, *mhip; 163 register struct ifnet *ifp; 164 register struct mbuf *m = m0; 165 register int hlen = sizeof (struct ip); 166 int len, off, error = 0; 167 struct route iproute; 168 struct sockaddr_in *dst; 169 #if IFA_STATS 170 struct sockaddr_in src; 171 #endif 172 struct in_ifaddr *ia; 173 struct mbuf *opt; 174 struct route *ro; 175 int flags; 176 int *mtu_p; 177 int mtu; 178 struct ip_moptions *imo; 179 va_list ap; 180 #ifdef PFIL_HOOKS 181 struct packet_filter_hook *pfh; 182 struct mbuf *m1; 183 int rv; 184 #endif /* PFIL_HOOKS */ 185 #ifdef IPSEC 186 struct socket *so; 187 struct secpolicy *sp = NULL; 188 #endif /*IPSEC*/ 189 190 va_start(ap, m0); 191 opt = va_arg(ap, struct mbuf *); 192 ro = va_arg(ap, struct route *); 193 flags = va_arg(ap, int); 194 imo = va_arg(ap, struct ip_moptions *); 195 if (flags & IP_RETURNMTU) 196 mtu_p = va_arg(ap, int *); 197 else 198 mtu_p = NULL; 199 va_end(ap); 200 201 #ifdef IPSEC 202 so = ipsec_getsocket(m); 203 ipsec_setsocket(m, NULL); 204 #endif /*IPSEC*/ 205 206 #ifdef DIAGNOSTIC 207 if ((m->m_flags & M_PKTHDR) == 0) 208 panic("ip_output no HDR"); 209 #endif 210 if (opt) { 211 m = ip_insertoptions(m, opt, &len); 212 hlen = len; 213 } 214 ip = mtod(m, struct ip *); 215 /* 216 * Fill in IP header. 217 */ 218 if ((flags & (IP_FORWARDING|IP_RAWOUTPUT)) == 0) { 219 ip->ip_v = IPVERSION; 220 ip->ip_off &= IP_DF; 221 ip->ip_id = htons(ip_id++); 222 ip->ip_hl = hlen >> 2; 223 ipstat.ips_localout++; 224 } else { 225 hlen = ip->ip_hl << 2; 226 } 227 /* 228 * Route packet. 229 */ 230 if (ro == 0) { 231 ro = &iproute; 232 bzero((caddr_t)ro, sizeof (*ro)); 233 } 234 dst = satosin(&ro->ro_dst); 235 /* 236 * If there is a cached route, 237 * check that it is to the same destination 238 * and is still up. If not, free it and try again. 239 */ 240 if (ro->ro_rt && ((ro->ro_rt->rt_flags & RTF_UP) == 0 || 241 !in_hosteq(dst->sin_addr, ip->ip_dst))) { 242 RTFREE(ro->ro_rt); 243 ro->ro_rt = (struct rtentry *)0; 244 } 245 if (ro->ro_rt == 0) { 246 dst->sin_family = AF_INET; 247 dst->sin_len = sizeof(*dst); 248 dst->sin_addr = ip->ip_dst; 249 } 250 /* 251 * If routing to interface only, 252 * short circuit routing lookup. 253 */ 254 if (flags & IP_ROUTETOIF) { 255 if ((ia = ifatoia(ifa_ifwithladdr(sintosa(dst)))) == 0) { 256 ipstat.ips_noroute++; 257 error = ENETUNREACH; 258 goto bad; 259 } 260 ifp = ia->ia_ifp; 261 mtu = ifp->if_mtu; 262 ip->ip_ttl = 1; 263 } else { 264 if (ro->ro_rt == 0) 265 rtalloc(ro); 266 if (ro->ro_rt == 0) { 267 ipstat.ips_noroute++; 268 error = EHOSTUNREACH; 269 goto bad; 270 } 271 ia = ifatoia(ro->ro_rt->rt_ifa); 272 ifp = ro->ro_rt->rt_ifp; 273 if ((mtu = ro->ro_rt->rt_rmx.rmx_mtu) == 0) 274 mtu = ifp->if_mtu; 275 ro->ro_rt->rt_use++; 276 if (ro->ro_rt->rt_flags & RTF_GATEWAY) 277 dst = satosin(ro->ro_rt->rt_gateway); 278 } 279 if (IN_MULTICAST(ip->ip_dst.s_addr) || 280 (ip->ip_dst.s_addr == INADDR_BROADCAST)) { 281 struct in_multi *inm; 282 283 m->m_flags |= (ip->ip_dst.s_addr == INADDR_BROADCAST) ? 284 M_BCAST : M_MCAST; 285 /* 286 * IP destination address is multicast. Make sure "dst" 287 * still points to the address in "ro". (It may have been 288 * changed to point to a gateway address, above.) 289 */ 290 dst = satosin(&ro->ro_dst); 291 /* 292 * See if the caller provided any multicast options 293 */ 294 if (imo != NULL) { 295 ip->ip_ttl = imo->imo_multicast_ttl; 296 if (imo->imo_multicast_ifp != NULL) { 297 ifp = imo->imo_multicast_ifp; 298 mtu = ifp->if_mtu; 299 } 300 } else 301 ip->ip_ttl = IP_DEFAULT_MULTICAST_TTL; 302 /* 303 * Confirm that the outgoing interface supports multicast. 304 */ 305 if (((m->m_flags & M_MCAST) && 306 (ifp->if_flags & IFF_MULTICAST) == 0) || 307 ((m->m_flags & M_BCAST) && 308 (ifp->if_flags & IFF_BROADCAST) == 0)) { 309 ipstat.ips_noroute++; 310 error = ENETUNREACH; 311 goto bad; 312 } 313 /* 314 * If source address not specified yet, use an address 315 * of outgoing interface. 316 */ 317 if (in_nullhost(ip->ip_src)) { 318 register struct in_ifaddr *ia; 319 320 IFP_TO_IA(ifp, ia); 321 ip->ip_src = ia->ia_addr.sin_addr; 322 } 323 324 IN_LOOKUP_MULTI(ip->ip_dst, ifp, inm); 325 if (inm != NULL && 326 (imo == NULL || imo->imo_multicast_loop)) { 327 /* 328 * If we belong to the destination multicast group 329 * on the outgoing interface, and the caller did not 330 * forbid loopback, loop back a copy. 331 */ 332 ip_mloopback(ifp, m, dst); 333 } 334 #ifdef MROUTING 335 else { 336 /* 337 * If we are acting as a multicast router, perform 338 * multicast forwarding as if the packet had just 339 * arrived on the interface to which we are about 340 * to send. The multicast forwarding function 341 * recursively calls this function, using the 342 * IP_FORWARDING flag to prevent infinite recursion. 343 * 344 * Multicasts that are looped back by ip_mloopback(), 345 * above, will be forwarded by the ip_input() routine, 346 * if necessary. 347 */ 348 extern struct socket *ip_mrouter; 349 350 if (ip_mrouter && (flags & IP_FORWARDING) == 0) { 351 if (ip_mforward(m, ifp) != 0) { 352 m_freem(m); 353 goto done; 354 } 355 } 356 } 357 #endif 358 /* 359 * Multicasts with a time-to-live of zero may be looped- 360 * back, above, but must not be transmitted on a network. 361 * Also, multicasts addressed to the loopback interface 362 * are not sent -- the above call to ip_mloopback() will 363 * loop back a copy if this host actually belongs to the 364 * destination group on the loopback interface. 365 */ 366 if (ip->ip_ttl == 0 || (ifp->if_flags & IFF_LOOPBACK) != 0) { 367 m_freem(m); 368 goto done; 369 } 370 371 goto sendit; 372 } 373 #ifndef notdef 374 /* 375 * If source address not specified yet, use address 376 * of outgoing interface. 377 */ 378 if (in_nullhost(ip->ip_src)) 379 ip->ip_src = ia->ia_addr.sin_addr; 380 #endif 381 382 /* 383 * packets with Class-D address as source are not valid per 384 * RFC 1112 385 */ 386 if (IN_MULTICAST(ip->ip_src.s_addr)) { 387 ipstat.ips_odropped++; 388 error = EADDRNOTAVAIL; 389 goto bad; 390 } 391 392 /* 393 * Look for broadcast address and 394 * and verify user is allowed to send 395 * such a packet. 396 */ 397 if (in_broadcast(dst->sin_addr, ifp)) { 398 if ((ifp->if_flags & IFF_BROADCAST) == 0) { 399 error = EADDRNOTAVAIL; 400 goto bad; 401 } 402 if ((flags & IP_ALLOWBROADCAST) == 0) { 403 error = EACCES; 404 goto bad; 405 } 406 /* don't allow broadcast messages to be fragmented */ 407 if ((u_int16_t)ip->ip_len > ifp->if_mtu) { 408 error = EMSGSIZE; 409 goto bad; 410 } 411 m->m_flags |= M_BCAST; 412 } else 413 m->m_flags &= ~M_BCAST; 414 415 sendit: 416 #ifdef PFIL_HOOKS 417 /* 418 * Run through list of hooks for output packets. 419 */ 420 m1 = m; 421 pfh = pfil_hook_get(PFIL_OUT, &inetsw[ip_protox[IPPROTO_IP]].pr_pfh); 422 for (; pfh; pfh = pfh->pfil_link.tqe_next) 423 if (pfh->pfil_func) { 424 rv = pfh->pfil_func(ip, hlen, ifp, 1, &m1); 425 if (rv) { 426 error = EHOSTUNREACH; 427 goto done; 428 } 429 m = m1; 430 if (m == NULL) 431 goto done; 432 ip = mtod(m, struct ip *); 433 } 434 #endif /* PFIL_HOOKS */ 435 436 #ifdef IPSEC 437 /* get SP for this packet */ 438 if (so == NULL) 439 sp = ipsec4_getpolicybyaddr(m, IPSEC_DIR_OUTBOUND, flags, &error); 440 else 441 sp = ipsec4_getpolicybysock(m, IPSEC_DIR_OUTBOUND, so, &error); 442 443 if (sp == NULL) { 444 ipsecstat.out_inval++; 445 goto bad; 446 } 447 448 error = 0; 449 450 /* check policy */ 451 switch (sp->policy) { 452 case IPSEC_POLICY_DISCARD: 453 /* 454 * This packet is just discarded. 455 */ 456 ipsecstat.out_polvio++; 457 goto bad; 458 459 case IPSEC_POLICY_BYPASS: 460 case IPSEC_POLICY_NONE: 461 /* no need to do IPsec. */ 462 goto skip_ipsec; 463 464 case IPSEC_POLICY_IPSEC: 465 if (sp->req == NULL) { 466 /* XXX should be panic ? */ 467 printf("ip_output: No IPsec request specified.\n"); 468 error = EINVAL; 469 goto bad; 470 } 471 break; 472 473 case IPSEC_POLICY_ENTRUST: 474 default: 475 printf("ip_output: Invalid policy found. %d\n", sp->policy); 476 } 477 478 ip->ip_len = htons((u_short)ip->ip_len); 479 ip->ip_off = htons((u_short)ip->ip_off); 480 ip->ip_sum = 0; 481 482 { 483 struct ipsec_output_state state; 484 bzero(&state, sizeof(state)); 485 state.m = m; 486 if (flags & IP_ROUTETOIF) { 487 state.ro = &iproute; 488 bzero(&iproute, sizeof(iproute)); 489 } else 490 state.ro = ro; 491 state.dst = (struct sockaddr *)dst; 492 493 error = ipsec4_output(&state, sp, flags); 494 495 m = state.m; 496 if (flags & IP_ROUTETOIF) { 497 /* 498 * if we have tunnel mode SA, we may need to ignore 499 * IP_ROUTETOIF. 500 */ 501 if (state.ro != &iproute || state.ro->ro_rt != NULL) { 502 flags &= ~IP_ROUTETOIF; 503 ro = state.ro; 504 } 505 } else 506 ro = state.ro; 507 dst = (struct sockaddr_in *)state.dst; 508 if (error) { 509 /* mbuf is already reclaimed in ipsec4_output. */ 510 m0 = NULL; 511 switch (error) { 512 case EHOSTUNREACH: 513 case ENETUNREACH: 514 case EMSGSIZE: 515 case ENOBUFS: 516 case ENOMEM: 517 break; 518 default: 519 printf("ip4_output (ipsec): error code %d\n", error); 520 /*fall through*/ 521 case ENOENT: 522 /* don't show these error codes to the user */ 523 error = 0; 524 break; 525 } 526 goto bad; 527 } 528 } 529 530 /* be sure to update variables that are affected by ipsec4_output() */ 531 ip = mtod(m, struct ip *); 532 #ifdef _IP_VHL 533 hlen = IP_VHL_HL(ip->ip_vhl) << 2; 534 #else 535 hlen = ip->ip_hl << 2; 536 #endif 537 if (ro->ro_rt == NULL) { 538 if ((flags & IP_ROUTETOIF) == 0) { 539 printf("ip_output: " 540 "can't update route after IPsec processing\n"); 541 error = EHOSTUNREACH; /*XXX*/ 542 goto bad; 543 } 544 } else { 545 /* nobody uses ia beyond here */ 546 ifp = ro->ro_rt->rt_ifp; 547 } 548 549 /* make it flipped, again. */ 550 ip->ip_len = ntohs((u_short)ip->ip_len); 551 ip->ip_off = ntohs((u_short)ip->ip_off); 552 skip_ipsec: 553 #endif /*IPSEC*/ 554 555 /* 556 * If small enough for mtu of path, can just send directly. 557 */ 558 if ((u_int16_t)ip->ip_len <= mtu) { 559 #if IFA_STATS 560 /* 561 * search for the source address structure to 562 * maintain output statistics. 563 */ 564 bzero((caddr_t*) &src, sizeof(src)); 565 src.sin_family = AF_INET; 566 src.sin_addr.s_addr = ip->ip_src.s_addr; 567 src.sin_len = sizeof(src); 568 ia = ifatoia(ifa_ifwithladdr(sintosa(&src))); 569 if (ia) 570 ia->ia_ifa.ifa_data.ifad_outbytes += ntohs(ip->ip_len); 571 #endif 572 HTONS(ip->ip_len); 573 HTONS(ip->ip_off); 574 ip->ip_sum = 0; 575 ip->ip_sum = in_cksum(m, hlen); 576 error = (*ifp->if_output)(ifp, m, sintosa(dst), ro->ro_rt); 577 goto done; 578 } 579 580 /* 581 * Too large for interface; fragment if possible. 582 * Must be able to put at least 8 bytes per fragment. 583 */ 584 #if 0 585 /* 586 * If IPsec packet is too big for the interface, try fragment it. 587 * XXX This really is a quickhack. May be inappropriate. 588 * XXX fails if somebody is sending AH'ed packet, with: 589 * sizeof(packet without AH) < mtu < sizeof(packet with AH) 590 */ 591 if (sab && ip->ip_p != IPPROTO_AH && (flags & IP_FORWARDING) == 0) 592 ip->ip_off &= ~IP_DF; 593 #endif /*IPSEC*/ 594 if (ip->ip_off & IP_DF) { 595 if (flags & IP_RETURNMTU) 596 *mtu_p = mtu; 597 error = EMSGSIZE; 598 ipstat.ips_cantfrag++; 599 goto bad; 600 } 601 len = (mtu - hlen) &~ 7; 602 if (len < 8) { 603 error = EMSGSIZE; 604 goto bad; 605 } 606 607 { 608 int mhlen, firstlen = len; 609 struct mbuf **mnext = &m->m_nextpkt; 610 int fragments = 0; 611 int s; 612 613 /* 614 * Loop through length of segment after first fragment, 615 * make new header and copy data of each part and link onto chain. 616 */ 617 m0 = m; 618 mhlen = sizeof (struct ip); 619 for (off = hlen + len; off < (u_int16_t)ip->ip_len; off += len) { 620 MGETHDR(m, M_DONTWAIT, MT_HEADER); 621 if (m == 0) { 622 error = ENOBUFS; 623 ipstat.ips_odropped++; 624 goto sendorfree; 625 } 626 *mnext = m; 627 mnext = &m->m_nextpkt; 628 m->m_data += max_linkhdr; 629 mhip = mtod(m, struct ip *); 630 *mhip = *ip; 631 if (hlen > sizeof (struct ip)) { 632 mhlen = ip_optcopy(ip, mhip) + sizeof (struct ip); 633 mhip->ip_hl = mhlen >> 2; 634 } 635 m->m_len = mhlen; 636 mhip->ip_off = ((off - hlen) >> 3) + (ip->ip_off & ~IP_MF); 637 if (ip->ip_off & IP_MF) 638 mhip->ip_off |= IP_MF; 639 if (off + len >= (u_int16_t)ip->ip_len) 640 len = (u_int16_t)ip->ip_len - off; 641 else 642 mhip->ip_off |= IP_MF; 643 mhip->ip_len = htons((u_int16_t)(len + mhlen)); 644 m->m_next = m_copy(m0, off, len); 645 if (m->m_next == 0) { 646 error = ENOBUFS; /* ??? */ 647 ipstat.ips_odropped++; 648 goto sendorfree; 649 } 650 m->m_pkthdr.len = mhlen + len; 651 m->m_pkthdr.rcvif = (struct ifnet *)0; 652 HTONS(mhip->ip_off); 653 mhip->ip_sum = 0; 654 mhip->ip_sum = in_cksum(m, mhlen); 655 ipstat.ips_ofragments++; 656 fragments++; 657 } 658 /* 659 * Update first fragment by trimming what's been copied out 660 * and updating header, then send each fragment (in order). 661 */ 662 m = m0; 663 m_adj(m, hlen + firstlen - (u_int16_t)ip->ip_len); 664 m->m_pkthdr.len = hlen + firstlen; 665 ip->ip_len = htons((u_int16_t)m->m_pkthdr.len); 666 ip->ip_off |= IP_MF; 667 HTONS(ip->ip_off); 668 ip->ip_sum = 0; 669 ip->ip_sum = in_cksum(m, hlen); 670 sendorfree: 671 /* 672 * If there is no room for all the fragments, don't queue 673 * any of them. 674 */ 675 s = splimp(); 676 if (ifp->if_snd.ifq_maxlen - ifp->if_snd.ifq_len < fragments) 677 error = ENOBUFS; 678 splx(s); 679 for (m = m0; m; m = m0) { 680 m0 = m->m_nextpkt; 681 m->m_nextpkt = 0; 682 if (error == 0) { 683 #if IFA_STATS 684 /* 685 * search for the source address structure to 686 * maintain output statistics. 687 */ 688 bzero((caddr_t*) &src, sizeof(src)); 689 src.sin_family = AF_INET; 690 src.sin_addr.s_addr = ip->ip_src.s_addr; 691 src.sin_len = sizeof(src); 692 ia = ifatoia(ifa_ifwithladdr(sintosa(&src))); 693 if (ia) { 694 ia->ia_ifa.ifa_data.ifad_outbytes += 695 ntohs(ip->ip_len); 696 } 697 #endif 698 error = (*ifp->if_output)(ifp, m, sintosa(dst), 699 ro->ro_rt); 700 } else 701 m_freem(m); 702 } 703 704 if (error == 0) 705 ipstat.ips_fragmented++; 706 } 707 done: 708 if (ro == &iproute && (flags & IP_ROUTETOIF) == 0 && ro->ro_rt) { 709 RTFREE(ro->ro_rt); 710 ro->ro_rt = 0; 711 } 712 713 #ifdef IPSEC 714 if (sp != NULL) { 715 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 716 printf("DP ip_output call free SP:%p\n", sp)); 717 key_freesp(sp); 718 } 719 #endif /* IPSEC */ 720 721 return (error); 722 bad: 723 m_freem(m); 724 goto done; 725 } 726 727 /* 728 * Determine the maximum length of the options to be inserted; 729 * we would far rather allocate too much space rather than too little. 730 */ 731 732 u_int 733 ip_optlen(inp) 734 struct inpcb *inp; 735 { 736 struct mbuf *m = inp->inp_options; 737 738 if (m && m->m_len > offsetof(struct ipoption, ipopt_dst)) 739 return(m->m_len - offsetof(struct ipoption, ipopt_dst)); 740 else 741 return 0; 742 } 743 744 745 /* 746 * Insert IP options into preformed packet. 747 * Adjust IP destination as required for IP source routing, 748 * as indicated by a non-zero in_addr at the start of the options. 749 */ 750 static struct mbuf * 751 ip_insertoptions(m, opt, phlen) 752 register struct mbuf *m; 753 struct mbuf *opt; 754 int *phlen; 755 { 756 register struct ipoption *p = mtod(opt, struct ipoption *); 757 struct mbuf *n; 758 register struct ip *ip = mtod(m, struct ip *); 759 unsigned optlen; 760 761 optlen = opt->m_len - sizeof(p->ipopt_dst); 762 if (optlen + (u_int16_t)ip->ip_len > IP_MAXPACKET) 763 return (m); /* XXX should fail */ 764 if (!in_nullhost(p->ipopt_dst)) 765 ip->ip_dst = p->ipopt_dst; 766 if (m->m_flags & M_EXT || m->m_data - optlen < m->m_pktdat) { 767 MGETHDR(n, M_DONTWAIT, MT_HEADER); 768 if (n == 0) 769 return (m); 770 n->m_pkthdr.len = m->m_pkthdr.len + optlen; 771 m->m_len -= sizeof(struct ip); 772 m->m_data += sizeof(struct ip); 773 n->m_next = m; 774 m = n; 775 m->m_len = optlen + sizeof(struct ip); 776 m->m_data += max_linkhdr; 777 bcopy((caddr_t)ip, mtod(m, caddr_t), sizeof(struct ip)); 778 } else { 779 m->m_data -= optlen; 780 m->m_len += optlen; 781 m->m_pkthdr.len += optlen; 782 memmove(mtod(m, caddr_t), ip, sizeof(struct ip)); 783 } 784 ip = mtod(m, struct ip *); 785 bcopy((caddr_t)p->ipopt_list, (caddr_t)(ip + 1), (unsigned)optlen); 786 *phlen = sizeof(struct ip) + optlen; 787 ip->ip_len += optlen; 788 return (m); 789 } 790 791 /* 792 * Copy options from ip to jp, 793 * omitting those not copied during fragmentation. 794 */ 795 int 796 ip_optcopy(ip, jp) 797 struct ip *ip, *jp; 798 { 799 register u_char *cp, *dp; 800 int opt, optlen, cnt; 801 802 cp = (u_char *)(ip + 1); 803 dp = (u_char *)(jp + 1); 804 cnt = (ip->ip_hl << 2) - sizeof (struct ip); 805 for (; cnt > 0; cnt -= optlen, cp += optlen) { 806 opt = cp[0]; 807 if (opt == IPOPT_EOL) 808 break; 809 if (opt == IPOPT_NOP) { 810 /* Preserve for IP mcast tunnel's LSRR alignment. */ 811 *dp++ = IPOPT_NOP; 812 optlen = 1; 813 continue; 814 } else 815 optlen = cp[IPOPT_OLEN]; 816 /* bogus lengths should have been caught by ip_dooptions */ 817 if (optlen > cnt) 818 optlen = cnt; 819 if (IPOPT_COPIED(opt)) { 820 bcopy((caddr_t)cp, (caddr_t)dp, (unsigned)optlen); 821 dp += optlen; 822 } 823 } 824 for (optlen = dp - (u_char *)(jp+1); optlen & 0x3; optlen++) 825 *dp++ = IPOPT_EOL; 826 return (optlen); 827 } 828 829 /* 830 * IP socket option processing. 831 */ 832 int 833 ip_ctloutput(op, so, level, optname, mp) 834 int op; 835 struct socket *so; 836 int level, optname; 837 struct mbuf **mp; 838 { 839 register struct inpcb *inp = sotoinpcb(so); 840 register struct mbuf *m = *mp; 841 register int optval = 0; 842 int error = 0; 843 #ifdef IPSEC 844 #ifdef __NetBSD__ 845 struct proc *p = curproc; /*XXX*/ 846 #endif 847 #endif 848 849 if (level != IPPROTO_IP) { 850 error = EINVAL; 851 if (op == PRCO_SETOPT && *mp) 852 (void) m_free(*mp); 853 } else switch (op) { 854 855 case PRCO_SETOPT: 856 switch (optname) { 857 case IP_OPTIONS: 858 #ifdef notyet 859 case IP_RETOPTS: 860 return (ip_pcbopts(optname, &inp->inp_options, m)); 861 #else 862 return (ip_pcbopts(&inp->inp_options, m)); 863 #endif 864 865 case IP_TOS: 866 case IP_TTL: 867 case IP_RECVOPTS: 868 case IP_RECVRETOPTS: 869 case IP_RECVDSTADDR: 870 case IP_RECVIF: 871 if (m == NULL || m->m_len != sizeof(int)) 872 error = EINVAL; 873 else { 874 optval = *mtod(m, int *); 875 switch (optname) { 876 877 case IP_TOS: 878 inp->inp_ip.ip_tos = optval; 879 break; 880 881 case IP_TTL: 882 inp->inp_ip.ip_ttl = optval; 883 break; 884 #define OPTSET(bit) \ 885 if (optval) \ 886 inp->inp_flags |= bit; \ 887 else \ 888 inp->inp_flags &= ~bit; 889 890 case IP_RECVOPTS: 891 OPTSET(INP_RECVOPTS); 892 break; 893 894 case IP_RECVRETOPTS: 895 OPTSET(INP_RECVRETOPTS); 896 break; 897 898 case IP_RECVDSTADDR: 899 OPTSET(INP_RECVDSTADDR); 900 break; 901 902 case IP_RECVIF: 903 OPTSET(INP_RECVIF); 904 break; 905 } 906 } 907 break; 908 #undef OPTSET 909 910 case IP_MULTICAST_IF: 911 case IP_MULTICAST_TTL: 912 case IP_MULTICAST_LOOP: 913 case IP_ADD_MEMBERSHIP: 914 case IP_DROP_MEMBERSHIP: 915 error = ip_setmoptions(optname, &inp->inp_moptions, m); 916 break; 917 918 case IP_PORTRANGE: 919 if (m == 0 || m->m_len != sizeof(int)) 920 error = EINVAL; 921 else { 922 optval = *mtod(m, int *); 923 924 switch (optval) { 925 926 case IP_PORTRANGE_DEFAULT: 927 case IP_PORTRANGE_HIGH: 928 inp->inp_flags &= ~(INP_LOWPORT); 929 break; 930 931 case IP_PORTRANGE_LOW: 932 inp->inp_flags |= INP_LOWPORT; 933 break; 934 935 default: 936 error = EINVAL; 937 break; 938 } 939 } 940 break; 941 942 #ifdef IPSEC 943 case IP_IPSEC_POLICY: 944 { 945 caddr_t req = NULL; 946 size_t len = 0; 947 int priv = 0; 948 949 #ifdef __NetBSD__ 950 if (p == 0 || suser(p->p_ucred, &p->p_acflag)) 951 priv = 0; 952 else 953 priv = 1; 954 #else 955 priv = (in6p->in6p_socket->so_state & SS_PRIV); 956 #endif 957 if (m) { 958 req = mtod(m, caddr_t); 959 len = m->m_len; 960 } 961 error = ipsec4_set_policy(inp, optname, req, len, priv); 962 break; 963 } 964 #endif /*IPSEC*/ 965 966 default: 967 error = ENOPROTOOPT; 968 break; 969 } 970 if (m) 971 (void)m_free(m); 972 break; 973 974 case PRCO_GETOPT: 975 switch (optname) { 976 case IP_OPTIONS: 977 case IP_RETOPTS: 978 *mp = m = m_get(M_WAIT, MT_SOOPTS); 979 if (inp->inp_options) { 980 m->m_len = inp->inp_options->m_len; 981 bcopy(mtod(inp->inp_options, caddr_t), 982 mtod(m, caddr_t), (unsigned)m->m_len); 983 } else 984 m->m_len = 0; 985 break; 986 987 case IP_TOS: 988 case IP_TTL: 989 case IP_RECVOPTS: 990 case IP_RECVRETOPTS: 991 case IP_RECVDSTADDR: 992 case IP_RECVIF: 993 case IP_ERRORMTU: 994 *mp = m = m_get(M_WAIT, MT_SOOPTS); 995 m->m_len = sizeof(int); 996 switch (optname) { 997 998 case IP_TOS: 999 optval = inp->inp_ip.ip_tos; 1000 break; 1001 1002 case IP_TTL: 1003 optval = inp->inp_ip.ip_ttl; 1004 break; 1005 1006 case IP_ERRORMTU: 1007 optval = inp->inp_errormtu; 1008 break; 1009 1010 #define OPTBIT(bit) (inp->inp_flags & bit ? 1 : 0) 1011 1012 case IP_RECVOPTS: 1013 optval = OPTBIT(INP_RECVOPTS); 1014 break; 1015 1016 case IP_RECVRETOPTS: 1017 optval = OPTBIT(INP_RECVRETOPTS); 1018 break; 1019 1020 case IP_RECVDSTADDR: 1021 optval = OPTBIT(INP_RECVDSTADDR); 1022 break; 1023 1024 case IP_RECVIF: 1025 optval = OPTBIT(INP_RECVIF); 1026 break; 1027 } 1028 *mtod(m, int *) = optval; 1029 break; 1030 1031 #ifdef IPSEC 1032 case IP_IPSEC_POLICY: 1033 { 1034 caddr_t req = NULL; 1035 size_t len; 1036 1037 if (m) { 1038 req = mtod(m, caddr_t); 1039 len = m->m_len; 1040 } 1041 error = ipsec4_get_policy(inp, req, len, mp); 1042 break; 1043 } 1044 #endif /*IPSEC*/ 1045 1046 case IP_MULTICAST_IF: 1047 case IP_MULTICAST_TTL: 1048 case IP_MULTICAST_LOOP: 1049 case IP_ADD_MEMBERSHIP: 1050 case IP_DROP_MEMBERSHIP: 1051 error = ip_getmoptions(optname, inp->inp_moptions, mp); 1052 break; 1053 1054 case IP_PORTRANGE: 1055 *mp = m = m_get(M_WAIT, MT_SOOPTS); 1056 m->m_len = sizeof(int); 1057 1058 if (inp->inp_flags & INP_LOWPORT) 1059 optval = IP_PORTRANGE_LOW; 1060 else 1061 optval = IP_PORTRANGE_DEFAULT; 1062 1063 *mtod(m, int *) = optval; 1064 break; 1065 1066 default: 1067 error = ENOPROTOOPT; 1068 break; 1069 } 1070 break; 1071 } 1072 return (error); 1073 } 1074 1075 /* 1076 * Set up IP options in pcb for insertion in output packets. 1077 * Store in mbuf with pointer in pcbopt, adding pseudo-option 1078 * with destination address if source routed. 1079 */ 1080 int 1081 #ifdef notyet 1082 ip_pcbopts(optname, pcbopt, m) 1083 int optname; 1084 #else 1085 ip_pcbopts(pcbopt, m) 1086 #endif 1087 struct mbuf **pcbopt; 1088 register struct mbuf *m; 1089 { 1090 register int cnt, optlen; 1091 register u_char *cp; 1092 u_char opt; 1093 1094 /* turn off any old options */ 1095 if (*pcbopt) 1096 (void)m_free(*pcbopt); 1097 *pcbopt = 0; 1098 if (m == (struct mbuf *)0 || m->m_len == 0) { 1099 /* 1100 * Only turning off any previous options. 1101 */ 1102 if (m) 1103 (void)m_free(m); 1104 return (0); 1105 } 1106 1107 #ifndef vax 1108 if (m->m_len % sizeof(int32_t)) 1109 goto bad; 1110 #endif 1111 /* 1112 * IP first-hop destination address will be stored before 1113 * actual options; move other options back 1114 * and clear it when none present. 1115 */ 1116 if (m->m_data + m->m_len + sizeof(struct in_addr) >= &m->m_dat[MLEN]) 1117 goto bad; 1118 cnt = m->m_len; 1119 m->m_len += sizeof(struct in_addr); 1120 cp = mtod(m, u_char *) + sizeof(struct in_addr); 1121 memmove(cp, mtod(m, caddr_t), (unsigned)cnt); 1122 bzero(mtod(m, caddr_t), sizeof(struct in_addr)); 1123 1124 for (; cnt > 0; cnt -= optlen, cp += optlen) { 1125 opt = cp[IPOPT_OPTVAL]; 1126 if (opt == IPOPT_EOL) 1127 break; 1128 if (opt == IPOPT_NOP) 1129 optlen = 1; 1130 else { 1131 optlen = cp[IPOPT_OLEN]; 1132 if (optlen <= IPOPT_OLEN || optlen > cnt) 1133 goto bad; 1134 } 1135 switch (opt) { 1136 1137 default: 1138 break; 1139 1140 case IPOPT_LSRR: 1141 case IPOPT_SSRR: 1142 /* 1143 * user process specifies route as: 1144 * ->A->B->C->D 1145 * D must be our final destination (but we can't 1146 * check that since we may not have connected yet). 1147 * A is first hop destination, which doesn't appear in 1148 * actual IP option, but is stored before the options. 1149 */ 1150 if (optlen < IPOPT_MINOFF - 1 + sizeof(struct in_addr)) 1151 goto bad; 1152 m->m_len -= sizeof(struct in_addr); 1153 cnt -= sizeof(struct in_addr); 1154 optlen -= sizeof(struct in_addr); 1155 cp[IPOPT_OLEN] = optlen; 1156 /* 1157 * Move first hop before start of options. 1158 */ 1159 bcopy((caddr_t)&cp[IPOPT_OFFSET+1], mtod(m, caddr_t), 1160 sizeof(struct in_addr)); 1161 /* 1162 * Then copy rest of options back 1163 * to close up the deleted entry. 1164 */ 1165 memmove(&cp[IPOPT_OFFSET+1], 1166 (caddr_t)(&cp[IPOPT_OFFSET+1] + sizeof(struct in_addr)), 1167 (unsigned)cnt + sizeof(struct in_addr)); 1168 break; 1169 } 1170 } 1171 if (m->m_len > MAX_IPOPTLEN + sizeof(struct in_addr)) 1172 goto bad; 1173 *pcbopt = m; 1174 return (0); 1175 1176 bad: 1177 (void)m_free(m); 1178 return (EINVAL); 1179 } 1180 1181 /* 1182 * Set the IP multicast options in response to user setsockopt(). 1183 */ 1184 int 1185 ip_setmoptions(optname, imop, m) 1186 int optname; 1187 struct ip_moptions **imop; 1188 struct mbuf *m; 1189 { 1190 register int error = 0; 1191 u_char loop; 1192 register int i; 1193 struct in_addr addr; 1194 register struct ip_mreq *mreq; 1195 register struct ifnet *ifp; 1196 register struct ip_moptions *imo = *imop; 1197 struct route ro; 1198 register struct sockaddr_in *dst; 1199 1200 if (imo == NULL) { 1201 /* 1202 * No multicast option buffer attached to the pcb; 1203 * allocate one and initialize to default values. 1204 */ 1205 imo = (struct ip_moptions *)malloc(sizeof(*imo), M_IPMOPTS, 1206 M_WAITOK); 1207 1208 if (imo == NULL) 1209 return (ENOBUFS); 1210 *imop = imo; 1211 imo->imo_multicast_ifp = NULL; 1212 imo->imo_multicast_ttl = IP_DEFAULT_MULTICAST_TTL; 1213 imo->imo_multicast_loop = IP_DEFAULT_MULTICAST_LOOP; 1214 imo->imo_num_memberships = 0; 1215 } 1216 1217 switch (optname) { 1218 1219 case IP_MULTICAST_IF: 1220 /* 1221 * Select the interface for outgoing multicast packets. 1222 */ 1223 if (m == NULL || m->m_len != sizeof(struct in_addr)) { 1224 error = EINVAL; 1225 break; 1226 } 1227 addr = *(mtod(m, struct in_addr *)); 1228 /* 1229 * INADDR_ANY is used to remove a previous selection. 1230 * When no interface is selected, a default one is 1231 * chosen every time a multicast packet is sent. 1232 */ 1233 if (in_nullhost(addr)) { 1234 imo->imo_multicast_ifp = NULL; 1235 break; 1236 } 1237 /* 1238 * The selected interface is identified by its local 1239 * IP address. Find the interface and confirm that 1240 * it supports multicasting. 1241 */ 1242 INADDR_TO_IFP(addr, ifp); 1243 if (ifp == NULL || (ifp->if_flags & IFF_MULTICAST) == 0) { 1244 error = EADDRNOTAVAIL; 1245 break; 1246 } 1247 imo->imo_multicast_ifp = ifp; 1248 break; 1249 1250 case IP_MULTICAST_TTL: 1251 /* 1252 * Set the IP time-to-live for outgoing multicast packets. 1253 */ 1254 if (m == NULL || m->m_len != 1) { 1255 error = EINVAL; 1256 break; 1257 } 1258 imo->imo_multicast_ttl = *(mtod(m, u_char *)); 1259 break; 1260 1261 case IP_MULTICAST_LOOP: 1262 /* 1263 * Set the loopback flag for outgoing multicast packets. 1264 * Must be zero or one. 1265 */ 1266 if (m == NULL || m->m_len != 1 || 1267 (loop = *(mtod(m, u_char *))) > 1) { 1268 error = EINVAL; 1269 break; 1270 } 1271 imo->imo_multicast_loop = loop; 1272 break; 1273 1274 case IP_ADD_MEMBERSHIP: 1275 /* 1276 * Add a multicast group membership. 1277 * Group must be a valid IP multicast address. 1278 */ 1279 if (m == NULL || m->m_len != sizeof(struct ip_mreq)) { 1280 error = EINVAL; 1281 break; 1282 } 1283 mreq = mtod(m, struct ip_mreq *); 1284 if (!IN_MULTICAST(mreq->imr_multiaddr.s_addr)) { 1285 error = EINVAL; 1286 break; 1287 } 1288 /* 1289 * If no interface address was provided, use the interface of 1290 * the route to the given multicast address. 1291 */ 1292 if (in_nullhost(mreq->imr_interface)) { 1293 bzero((caddr_t)&ro, sizeof(ro)); 1294 ro.ro_rt = NULL; 1295 dst = satosin(&ro.ro_dst); 1296 dst->sin_len = sizeof(*dst); 1297 dst->sin_family = AF_INET; 1298 dst->sin_addr = mreq->imr_multiaddr; 1299 rtalloc(&ro); 1300 if (ro.ro_rt == NULL) { 1301 error = EADDRNOTAVAIL; 1302 break; 1303 } 1304 ifp = ro.ro_rt->rt_ifp; 1305 rtfree(ro.ro_rt); 1306 } else { 1307 INADDR_TO_IFP(mreq->imr_interface, ifp); 1308 } 1309 /* 1310 * See if we found an interface, and confirm that it 1311 * supports multicast. 1312 */ 1313 if (ifp == NULL || (ifp->if_flags & IFF_MULTICAST) == 0) { 1314 error = EADDRNOTAVAIL; 1315 break; 1316 } 1317 /* 1318 * See if the membership already exists or if all the 1319 * membership slots are full. 1320 */ 1321 for (i = 0; i < imo->imo_num_memberships; ++i) { 1322 if (imo->imo_membership[i]->inm_ifp == ifp && 1323 in_hosteq(imo->imo_membership[i]->inm_addr, 1324 mreq->imr_multiaddr)) 1325 break; 1326 } 1327 if (i < imo->imo_num_memberships) { 1328 error = EADDRINUSE; 1329 break; 1330 } 1331 if (i == IP_MAX_MEMBERSHIPS) { 1332 error = ETOOMANYREFS; 1333 break; 1334 } 1335 /* 1336 * Everything looks good; add a new record to the multicast 1337 * address list for the given interface. 1338 */ 1339 if ((imo->imo_membership[i] = 1340 in_addmulti(&mreq->imr_multiaddr, ifp)) == NULL) { 1341 error = ENOBUFS; 1342 break; 1343 } 1344 ++imo->imo_num_memberships; 1345 break; 1346 1347 case IP_DROP_MEMBERSHIP: 1348 /* 1349 * Drop a multicast group membership. 1350 * Group must be a valid IP multicast address. 1351 */ 1352 if (m == NULL || m->m_len != sizeof(struct ip_mreq)) { 1353 error = EINVAL; 1354 break; 1355 } 1356 mreq = mtod(m, struct ip_mreq *); 1357 if (!IN_MULTICAST(mreq->imr_multiaddr.s_addr)) { 1358 error = EINVAL; 1359 break; 1360 } 1361 /* 1362 * If an interface address was specified, get a pointer 1363 * to its ifnet structure. 1364 */ 1365 if (in_nullhost(mreq->imr_interface)) 1366 ifp = NULL; 1367 else { 1368 INADDR_TO_IFP(mreq->imr_interface, ifp); 1369 if (ifp == NULL) { 1370 error = EADDRNOTAVAIL; 1371 break; 1372 } 1373 } 1374 /* 1375 * Find the membership in the membership array. 1376 */ 1377 for (i = 0; i < imo->imo_num_memberships; ++i) { 1378 if ((ifp == NULL || 1379 imo->imo_membership[i]->inm_ifp == ifp) && 1380 in_hosteq(imo->imo_membership[i]->inm_addr, 1381 mreq->imr_multiaddr)) 1382 break; 1383 } 1384 if (i == imo->imo_num_memberships) { 1385 error = EADDRNOTAVAIL; 1386 break; 1387 } 1388 /* 1389 * Give up the multicast address record to which the 1390 * membership points. 1391 */ 1392 in_delmulti(imo->imo_membership[i]); 1393 /* 1394 * Remove the gap in the membership array. 1395 */ 1396 for (++i; i < imo->imo_num_memberships; ++i) 1397 imo->imo_membership[i-1] = imo->imo_membership[i]; 1398 --imo->imo_num_memberships; 1399 break; 1400 1401 default: 1402 error = EOPNOTSUPP; 1403 break; 1404 } 1405 1406 /* 1407 * If all options have default values, no need to keep the mbuf. 1408 */ 1409 if (imo->imo_multicast_ifp == NULL && 1410 imo->imo_multicast_ttl == IP_DEFAULT_MULTICAST_TTL && 1411 imo->imo_multicast_loop == IP_DEFAULT_MULTICAST_LOOP && 1412 imo->imo_num_memberships == 0) { 1413 free(*imop, M_IPMOPTS); 1414 *imop = NULL; 1415 } 1416 1417 return (error); 1418 } 1419 1420 /* 1421 * Return the IP multicast options in response to user getsockopt(). 1422 */ 1423 int 1424 ip_getmoptions(optname, imo, mp) 1425 int optname; 1426 register struct ip_moptions *imo; 1427 register struct mbuf **mp; 1428 { 1429 u_char *ttl; 1430 u_char *loop; 1431 struct in_addr *addr; 1432 struct in_ifaddr *ia; 1433 1434 *mp = m_get(M_WAIT, MT_SOOPTS); 1435 1436 switch (optname) { 1437 1438 case IP_MULTICAST_IF: 1439 addr = mtod(*mp, struct in_addr *); 1440 (*mp)->m_len = sizeof(struct in_addr); 1441 if (imo == NULL || imo->imo_multicast_ifp == NULL) 1442 *addr = zeroin_addr; 1443 else { 1444 IFP_TO_IA(imo->imo_multicast_ifp, ia); 1445 *addr = ia ? ia->ia_addr.sin_addr : zeroin_addr; 1446 } 1447 return (0); 1448 1449 case IP_MULTICAST_TTL: 1450 ttl = mtod(*mp, u_char *); 1451 (*mp)->m_len = 1; 1452 *ttl = imo ? imo->imo_multicast_ttl 1453 : IP_DEFAULT_MULTICAST_TTL; 1454 return (0); 1455 1456 case IP_MULTICAST_LOOP: 1457 loop = mtod(*mp, u_char *); 1458 (*mp)->m_len = 1; 1459 *loop = imo ? imo->imo_multicast_loop 1460 : IP_DEFAULT_MULTICAST_LOOP; 1461 return (0); 1462 1463 default: 1464 return (EOPNOTSUPP); 1465 } 1466 } 1467 1468 /* 1469 * Discard the IP multicast options. 1470 */ 1471 void 1472 ip_freemoptions(imo) 1473 register struct ip_moptions *imo; 1474 { 1475 register int i; 1476 1477 if (imo != NULL) { 1478 for (i = 0; i < imo->imo_num_memberships; ++i) 1479 in_delmulti(imo->imo_membership[i]); 1480 free(imo, M_IPMOPTS); 1481 } 1482 } 1483 1484 /* 1485 * Routine called from ip_output() to loop back a copy of an IP multicast 1486 * packet to the input queue of a specified interface. Note that this 1487 * calls the output routine of the loopback "driver", but with an interface 1488 * pointer that might NOT be &loif -- easier than replicating that code here. 1489 */ 1490 static void 1491 ip_mloopback(ifp, m, dst) 1492 struct ifnet *ifp; 1493 register struct mbuf *m; 1494 register struct sockaddr_in *dst; 1495 { 1496 register struct ip *ip; 1497 struct mbuf *copym; 1498 1499 copym = m_copy(m, 0, M_COPYALL); 1500 if (copym != NULL 1501 && (copym->m_flags & M_EXT || copym->m_len < sizeof(struct ip))) 1502 copym = m_pullup(copym, sizeof(struct ip)); 1503 if (copym != NULL) { 1504 /* 1505 * We don't bother to fragment if the IP length is greater 1506 * than the interface's MTU. Can this possibly matter? 1507 */ 1508 ip = mtod(copym, struct ip *); 1509 HTONS(ip->ip_len); 1510 HTONS(ip->ip_off); 1511 ip->ip_sum = 0; 1512 ip->ip_sum = in_cksum(copym, ip->ip_hl << 2); 1513 (void) looutput(ifp, copym, sintosa(dst), NULL); 1514 } 1515 } 1516