1 /* $NetBSD: ip_output.c,v 1.324 2022/11/21 09:51:13 knakahara 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 * 49 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 50 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 51 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 52 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 53 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 54 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 55 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 56 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 57 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 58 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 59 * POSSIBILITY OF SUCH DAMAGE. 60 */ 61 62 /* 63 * Copyright (c) 1982, 1986, 1988, 1990, 1993 64 * The Regents of the University of California. All rights reserved. 65 * 66 * Redistribution and use in source and binary forms, with or without 67 * modification, are permitted provided that the following conditions 68 * are met: 69 * 1. Redistributions of source code must retain the above copyright 70 * notice, this list of conditions and the following disclaimer. 71 * 2. Redistributions in binary form must reproduce the above copyright 72 * notice, this list of conditions and the following disclaimer in the 73 * documentation and/or other materials provided with the distribution. 74 * 3. Neither the name of the University nor the names of its contributors 75 * may be used to endorse or promote products derived from this software 76 * without specific prior written permission. 77 * 78 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 79 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 80 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 81 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 82 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 83 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 84 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 85 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 86 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 87 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 88 * SUCH DAMAGE. 89 * 90 * @(#)ip_output.c 8.3 (Berkeley) 1/21/94 91 */ 92 93 #include <sys/cdefs.h> 94 __KERNEL_RCSID(0, "$NetBSD: ip_output.c,v 1.324 2022/11/21 09:51:13 knakahara Exp $"); 95 96 #ifdef _KERNEL_OPT 97 #include "opt_inet.h" 98 #include "opt_ipsec.h" 99 #include "opt_mrouting.h" 100 #include "opt_net_mpsafe.h" 101 #include "opt_mpls.h" 102 #endif 103 104 #include "arp.h" 105 106 #include <sys/param.h> 107 #include <sys/kmem.h> 108 #include <sys/mbuf.h> 109 #include <sys/socket.h> 110 #include <sys/socketvar.h> 111 #include <sys/kauth.h> 112 #include <sys/systm.h> 113 #include <sys/syslog.h> 114 115 #include <net/if.h> 116 #include <net/if_types.h> 117 #include <net/route.h> 118 #include <net/pfil.h> 119 120 #include <netinet/in.h> 121 #include <netinet/in_systm.h> 122 #include <netinet/ip.h> 123 #include <netinet/in_pcb.h> 124 #include <netinet/in_var.h> 125 #include <netinet/ip_var.h> 126 #include <netinet/ip_private.h> 127 #include <netinet/in_offload.h> 128 #include <netinet/portalgo.h> 129 #include <netinet/udp.h> 130 #include <netinet/udp_var.h> 131 132 #ifdef INET6 133 #include <netinet6/ip6_var.h> 134 #endif 135 136 #ifdef MROUTING 137 #include <netinet/ip_mroute.h> 138 #endif 139 140 #ifdef IPSEC 141 #include <netipsec/ipsec.h> 142 #include <netipsec/key.h> 143 #endif 144 145 #ifdef MPLS 146 #include <netmpls/mpls.h> 147 #include <netmpls/mpls_var.h> 148 #endif 149 150 static int ip_pcbopts(struct inpcb *, const struct sockopt *); 151 static struct mbuf *ip_insertoptions(struct mbuf *, struct mbuf *, int *); 152 static struct ifnet *ip_multicast_if(struct in_addr *, int *); 153 static void ip_mloopback(struct ifnet *, struct mbuf *, 154 const struct sockaddr_in *); 155 static int ip_ifaddrvalid(const struct in_ifaddr *); 156 157 extern pfil_head_t *inet_pfil_hook; /* XXX */ 158 159 int ip_do_loopback_cksum = 0; 160 161 static int 162 ip_mark_mpls(struct ifnet * const ifp, struct mbuf * const m, 163 const struct rtentry *rt) 164 { 165 int error = 0; 166 #ifdef MPLS 167 union mpls_shim msh; 168 169 if (rt == NULL || rt_gettag(rt) == NULL || 170 rt_gettag(rt)->sa_family != AF_MPLS || 171 (m->m_flags & (M_MCAST | M_BCAST)) != 0 || 172 ifp->if_type != IFT_ETHER) 173 return 0; 174 175 msh.s_addr = MPLS_GETSADDR(rt); 176 if (msh.shim.label != MPLS_LABEL_IMPLNULL) { 177 struct m_tag *mtag; 178 /* 179 * XXX tentative solution to tell ether_output 180 * it's MPLS. Need some more efficient solution. 181 */ 182 mtag = m_tag_get(PACKET_TAG_MPLS, 183 sizeof(int) /* dummy */, 184 M_NOWAIT); 185 if (mtag == NULL) 186 return ENOMEM; 187 m_tag_prepend(m, mtag); 188 } 189 #endif 190 return error; 191 } 192 193 /* 194 * Send an IP packet to a host. 195 */ 196 int 197 ip_if_output(struct ifnet * const ifp, struct mbuf * const m, 198 const struct sockaddr * const dst, const struct rtentry *rt) 199 { 200 int error = 0; 201 202 if (rt != NULL) { 203 error = rt_check_reject_route(rt, ifp); 204 if (error != 0) { 205 IP_STATINC(IP_STAT_RTREJECT); 206 m_freem(m); 207 return error; 208 } 209 } 210 211 error = ip_mark_mpls(ifp, m, rt); 212 if (error != 0) { 213 m_freem(m); 214 return error; 215 } 216 217 error = if_output_lock(ifp, ifp, m, dst, rt); 218 219 return error; 220 } 221 222 /* 223 * IP output. The packet in mbuf chain m contains a skeletal IP 224 * header (with len, off, ttl, proto, tos, src, dst). 225 * The mbuf chain containing the packet will be freed. 226 * The mbuf opt, if present, will not be freed. 227 */ 228 int 229 ip_output(struct mbuf *m0, struct mbuf *opt, struct route *ro, int flags, 230 struct ip_moptions *imo, struct inpcb *inp) 231 { 232 struct rtentry *rt; 233 struct ip *ip; 234 struct ifnet *ifp, *mifp = NULL; 235 struct mbuf *m = m0; 236 int len, hlen, error = 0; 237 struct route iproute; 238 const struct sockaddr_in *dst; 239 struct in_ifaddr *ia = NULL; 240 struct ifaddr *ifa; 241 int isbroadcast; 242 int sw_csum; 243 u_long mtu; 244 bool natt_frag = false; 245 bool rtmtu_nolock; 246 union { 247 struct sockaddr sa; 248 struct sockaddr_in sin; 249 } udst, usrc; 250 struct sockaddr *rdst = &udst.sa; /* real IP destination, as 251 * opposed to the nexthop 252 */ 253 struct psref psref, psref_ia; 254 int bound; 255 bool bind_need_restore = false; 256 const struct sockaddr *sa; 257 258 len = 0; 259 260 MCLAIM(m, &ip_tx_mowner); 261 262 KASSERT((m->m_flags & M_PKTHDR) != 0); 263 KASSERT((m->m_pkthdr.csum_flags & (M_CSUM_TCPv6|M_CSUM_UDPv6)) == 0); 264 KASSERT((m->m_pkthdr.csum_flags & (M_CSUM_TCPv4|M_CSUM_UDPv4)) != 265 (M_CSUM_TCPv4|M_CSUM_UDPv4)); 266 KASSERT(m->m_len >= sizeof(struct ip)); 267 268 hlen = sizeof(struct ip); 269 if (opt) { 270 m = ip_insertoptions(m, opt, &len); 271 hlen = len; 272 } 273 ip = mtod(m, struct ip *); 274 275 /* 276 * Fill in IP header. 277 */ 278 if ((flags & (IP_FORWARDING|IP_RAWOUTPUT)) == 0) { 279 ip->ip_v = IPVERSION; 280 ip->ip_off = htons(0); 281 /* ip->ip_id filled in after we find out source ia */ 282 ip->ip_hl = hlen >> 2; 283 IP_STATINC(IP_STAT_LOCALOUT); 284 } else { 285 hlen = ip->ip_hl << 2; 286 } 287 288 /* 289 * Route packet. 290 */ 291 if (ro == NULL) { 292 memset(&iproute, 0, sizeof(iproute)); 293 ro = &iproute; 294 } 295 sockaddr_in_init(&udst.sin, &ip->ip_dst, 0); 296 dst = satocsin(rtcache_getdst(ro)); 297 298 /* 299 * If there is a cached route, check that it is to the same 300 * destination and is still up. If not, free it and try again. 301 * The address family should also be checked in case of sharing 302 * the cache with IPv6. 303 */ 304 if (dst && (dst->sin_family != AF_INET || 305 !in_hosteq(dst->sin_addr, ip->ip_dst))) 306 rtcache_free(ro); 307 308 /* XXX must be before rtcache operations */ 309 bound = curlwp_bind(); 310 bind_need_restore = true; 311 312 if ((rt = rtcache_validate(ro)) == NULL && 313 (rt = rtcache_update(ro, 1)) == NULL) { 314 dst = &udst.sin; 315 error = rtcache_setdst(ro, &udst.sa); 316 if (error != 0) { 317 IP_STATINC(IP_STAT_ODROPPED); 318 goto bad; 319 } 320 } 321 322 /* 323 * If routing to interface only, short circuit routing lookup. 324 */ 325 if (flags & IP_ROUTETOIF) { 326 ifa = ifa_ifwithladdr_psref(sintocsa(dst), &psref_ia); 327 if (ifa == NULL) { 328 IP_STATINC(IP_STAT_NOROUTE); 329 error = ENETUNREACH; 330 goto bad; 331 } 332 /* ia is already referenced by psref_ia */ 333 ia = ifatoia(ifa); 334 335 ifp = ia->ia_ifp; 336 mtu = ifp->if_mtu; 337 ip->ip_ttl = 1; 338 isbroadcast = in_broadcast(dst->sin_addr, ifp); 339 } else if (((IN_MULTICAST(ip->ip_dst.s_addr) || 340 ip->ip_dst.s_addr == INADDR_BROADCAST) || 341 (flags & IP_ROUTETOIFINDEX)) && 342 imo != NULL && imo->imo_multicast_if_index != 0) { 343 ifp = mifp = if_get_byindex(imo->imo_multicast_if_index, &psref); 344 if (ifp == NULL) { 345 IP_STATINC(IP_STAT_NOROUTE); 346 error = ENETUNREACH; 347 goto bad; 348 } 349 mtu = ifp->if_mtu; 350 ia = in_get_ia_from_ifp_psref(ifp, &psref_ia); 351 if (ia == NULL) { 352 IP_STATINC(IP_STAT_IFNOADDR); 353 error = EADDRNOTAVAIL; 354 goto bad; 355 } 356 if (IN_MULTICAST(ip->ip_dst.s_addr) || 357 ip->ip_dst.s_addr == INADDR_BROADCAST) { 358 isbroadcast = 0; 359 } else { 360 /* IP_ROUTETOIFINDEX */ 361 isbroadcast = in_broadcast(dst->sin_addr, ifp); 362 if ((isbroadcast == 0) && ((ifp->if_flags & 363 (IFF_LOOPBACK | IFF_POINTOPOINT)) == 0) && 364 (in_direct(dst->sin_addr, ifp) == 0)) { 365 /* gateway address required */ 366 if (rt == NULL) 367 rt = rtcache_init(ro); 368 if (rt == NULL || rt->rt_ifp != ifp) { 369 IP_STATINC(IP_STAT_NOROUTE); 370 error = EHOSTUNREACH; 371 goto bad; 372 } 373 rt->rt_use++; 374 if (rt->rt_flags & RTF_GATEWAY) 375 dst = satosin(rt->rt_gateway); 376 if (rt->rt_flags & RTF_HOST) 377 isbroadcast = 378 rt->rt_flags & RTF_BROADCAST; 379 } 380 } 381 } else { 382 if (rt == NULL) 383 rt = rtcache_init(ro); 384 if (rt == NULL) { 385 IP_STATINC(IP_STAT_NOROUTE); 386 error = EHOSTUNREACH; 387 goto bad; 388 } 389 if (ifa_is_destroying(rt->rt_ifa)) { 390 rtcache_unref(rt, ro); 391 rt = NULL; 392 IP_STATINC(IP_STAT_NOROUTE); 393 error = EHOSTUNREACH; 394 goto bad; 395 } 396 ifa_acquire(rt->rt_ifa, &psref_ia); 397 ia = ifatoia(rt->rt_ifa); 398 ifp = rt->rt_ifp; 399 if ((mtu = rt->rt_rmx.rmx_mtu) == 0) 400 mtu = ifp->if_mtu; 401 rt->rt_use++; 402 if (rt->rt_flags & RTF_GATEWAY) 403 dst = satosin(rt->rt_gateway); 404 if (rt->rt_flags & RTF_HOST) 405 isbroadcast = rt->rt_flags & RTF_BROADCAST; 406 else 407 isbroadcast = in_broadcast(dst->sin_addr, ifp); 408 } 409 rtmtu_nolock = rt && (rt->rt_rmx.rmx_locks & RTV_MTU) == 0; 410 411 if (IN_MULTICAST(ip->ip_dst.s_addr) || 412 (ip->ip_dst.s_addr == INADDR_BROADCAST)) { 413 bool inmgroup; 414 415 m->m_flags |= (ip->ip_dst.s_addr == INADDR_BROADCAST) ? 416 M_BCAST : M_MCAST; 417 /* 418 * See if the caller provided any multicast options 419 */ 420 if (imo != NULL) 421 ip->ip_ttl = imo->imo_multicast_ttl; 422 else 423 ip->ip_ttl = IP_DEFAULT_MULTICAST_TTL; 424 425 /* 426 * if we don't know the outgoing ifp yet, we can't generate 427 * output 428 */ 429 if (!ifp) { 430 IP_STATINC(IP_STAT_NOROUTE); 431 error = ENETUNREACH; 432 goto bad; 433 } 434 435 /* 436 * If the packet is multicast or broadcast, confirm that 437 * the outgoing interface can transmit it. 438 */ 439 if (((m->m_flags & M_MCAST) && 440 (ifp->if_flags & IFF_MULTICAST) == 0) || 441 ((m->m_flags & M_BCAST) && 442 (ifp->if_flags & (IFF_BROADCAST|IFF_POINTOPOINT)) == 0)) { 443 IP_STATINC(IP_STAT_NOROUTE); 444 error = ENETUNREACH; 445 goto bad; 446 } 447 /* 448 * If source address not specified yet, use an address 449 * of outgoing interface. 450 */ 451 if (in_nullhost(ip->ip_src)) { 452 struct in_ifaddr *xia; 453 struct ifaddr *xifa; 454 struct psref _psref; 455 456 xia = in_get_ia_from_ifp_psref(ifp, &_psref); 457 if (!xia) { 458 IP_STATINC(IP_STAT_IFNOADDR); 459 error = EADDRNOTAVAIL; 460 goto bad; 461 } 462 xifa = &xia->ia_ifa; 463 if (xifa->ifa_getifa != NULL) { 464 ia4_release(xia, &_psref); 465 /* FIXME ifa_getifa is NOMPSAFE */ 466 xia = ifatoia((*xifa->ifa_getifa)(xifa, rdst)); 467 if (xia == NULL) { 468 IP_STATINC(IP_STAT_IFNOADDR); 469 error = EADDRNOTAVAIL; 470 goto bad; 471 } 472 ia4_acquire(xia, &_psref); 473 } 474 ip->ip_src = xia->ia_addr.sin_addr; 475 ia4_release(xia, &_psref); 476 } 477 478 inmgroup = in_multi_group(ip->ip_dst, ifp, flags); 479 if (inmgroup && (imo == NULL || imo->imo_multicast_loop)) { 480 /* 481 * If we belong to the destination multicast group 482 * on the outgoing interface, and the caller did not 483 * forbid loopback, loop back a copy. 484 */ 485 ip_mloopback(ifp, m, &udst.sin); 486 } 487 #ifdef MROUTING 488 else { 489 /* 490 * If we are acting as a multicast router, perform 491 * multicast forwarding as if the packet had just 492 * arrived on the interface to which we are about 493 * to send. The multicast forwarding function 494 * recursively calls this function, using the 495 * IP_FORWARDING flag to prevent infinite recursion. 496 * 497 * Multicasts that are looped back by ip_mloopback(), 498 * above, will be forwarded by the ip_input() routine, 499 * if necessary. 500 */ 501 extern struct socket *ip_mrouter; 502 503 if (ip_mrouter && (flags & IP_FORWARDING) == 0) { 504 if (ip_mforward(m, ifp) != 0) { 505 m_freem(m); 506 goto done; 507 } 508 } 509 } 510 #endif 511 /* 512 * Multicasts with a time-to-live of zero may be looped- 513 * back, above, but must not be transmitted on a network. 514 * Also, multicasts addressed to the loopback interface 515 * are not sent -- the above call to ip_mloopback() will 516 * loop back a copy if this host actually belongs to the 517 * destination group on the loopback interface. 518 */ 519 if (ip->ip_ttl == 0 || (ifp->if_flags & IFF_LOOPBACK) != 0) { 520 IP_STATINC(IP_STAT_ODROPPED); 521 m_freem(m); 522 goto done; 523 } 524 goto sendit; 525 } 526 527 /* 528 * If source address not specified yet, use address 529 * of outgoing interface. 530 */ 531 if (in_nullhost(ip->ip_src)) { 532 struct ifaddr *xifa; 533 534 /* If rt_ifa is AF_LINK, ia can be NULL. */ 535 if (ia == NULL) { 536 KASSERTMSG(rt->rt_ifa->ifa_addr->sa_family == AF_LINK, 537 "sa_family=%d", rt->rt_ifa->ifa_addr->sa_family); 538 IP_STATINC(IP_STAT_NOROUTE); 539 error = EHOSTUNREACH; 540 goto bad; 541 } 542 543 xifa = &ia->ia_ifa; 544 if (xifa->ifa_getifa != NULL) { 545 ia4_release(ia, &psref_ia); 546 /* FIXME ifa_getifa is NOMPSAFE */ 547 ia = ifatoia((*xifa->ifa_getifa)(xifa, rdst)); 548 if (ia == NULL) { 549 error = EADDRNOTAVAIL; 550 goto bad; 551 } 552 ia4_acquire(ia, &psref_ia); 553 } 554 ip->ip_src = ia->ia_addr.sin_addr; 555 } 556 557 /* 558 * Packets with Class-D address as source are not valid per 559 * RFC1112. 560 */ 561 if (IN_MULTICAST(ip->ip_src.s_addr)) { 562 IP_STATINC(IP_STAT_ODROPPED); 563 error = EADDRNOTAVAIL; 564 goto bad; 565 } 566 567 /* 568 * Look for broadcast address and verify user is allowed to 569 * send such a packet. 570 */ 571 if (isbroadcast) { 572 if ((ifp->if_flags & IFF_BROADCAST) == 0) { 573 IP_STATINC(IP_STAT_BCASTDENIED); 574 error = EADDRNOTAVAIL; 575 goto bad; 576 } 577 if ((flags & IP_ALLOWBROADCAST) == 0) { 578 IP_STATINC(IP_STAT_BCASTDENIED); 579 error = EACCES; 580 goto bad; 581 } 582 /* don't allow broadcast messages to be fragmented */ 583 if (ntohs(ip->ip_len) > ifp->if_mtu) { 584 IP_STATINC(IP_STAT_BCASTDENIED); 585 error = EMSGSIZE; 586 goto bad; 587 } 588 m->m_flags |= M_BCAST; 589 } else 590 m->m_flags &= ~M_BCAST; 591 592 sendit: 593 if ((flags & (IP_FORWARDING|IP_NOIPNEWID)) == 0) { 594 /* If rt_ifa is AF_LINK, ia can be NULL. */ 595 if (ia == NULL) { 596 KASSERTMSG(rt->rt_ifa->ifa_addr->sa_family == AF_LINK, 597 "sa_family=%d", rt->rt_ifa->ifa_addr->sa_family); 598 IP_STATINC(IP_STAT_NOROUTE); 599 error = EHOSTUNREACH; 600 goto bad; 601 } 602 603 if (m->m_pkthdr.len < IP_MINFRAGSIZE) { 604 ip->ip_id = 0; 605 } else if ((m->m_pkthdr.csum_flags & M_CSUM_TSOv4) == 0) { 606 ip->ip_id = ip_newid(ia); 607 } else { 608 /* 609 * TSO capable interfaces (typically?) increment 610 * ip_id for each segment. 611 * "allocate" enough ids here to increase the chance 612 * for them to be unique. 613 * 614 * note that the following calculation is not 615 * needed to be precise. wasting some ip_id is fine. 616 */ 617 618 unsigned int segsz = m->m_pkthdr.segsz; 619 unsigned int datasz = ntohs(ip->ip_len) - hlen; 620 unsigned int num = howmany(datasz, segsz); 621 622 ip->ip_id = ip_newid_range(ia, num); 623 } 624 } 625 if (ia != NULL) { 626 ia4_release(ia, &psref_ia); 627 ia = NULL; 628 } 629 630 /* 631 * If we're doing Path MTU Discovery, we need to set DF unless 632 * the route's MTU is locked. 633 */ 634 if ((flags & IP_MTUDISC) != 0 && rtmtu_nolock) { 635 ip->ip_off |= htons(IP_DF); 636 } 637 638 #ifdef IPSEC 639 if (ipsec_used) { 640 bool ipsec_done = false; 641 bool count_drop = false; 642 643 /* Perform IPsec processing, if any. */ 644 error = ipsec4_output(m, inp, flags, &mtu, &natt_frag, 645 &ipsec_done, &count_drop); 646 if (count_drop) 647 IP_STATINC(IP_STAT_IPSECDROP_OUT); 648 if (error || ipsec_done) 649 goto done; 650 } 651 652 if (!ipsec_used || !natt_frag) 653 #endif 654 { 655 /* 656 * Run through list of hooks for output packets. 657 */ 658 error = pfil_run_hooks(inet_pfil_hook, &m, ifp, PFIL_OUT); 659 if (error || m == NULL) { 660 IP_STATINC(IP_STAT_PFILDROP_OUT); 661 goto done; 662 } 663 } 664 665 ip = mtod(m, struct ip *); 666 hlen = ip->ip_hl << 2; 667 668 m->m_pkthdr.csum_data |= hlen << 16; 669 670 /* 671 * search for the source address structure to 672 * maintain output statistics, and verify address 673 * validity 674 */ 675 KASSERT(ia == NULL); 676 sockaddr_in_init(&usrc.sin, &ip->ip_src, 0); 677 ifa = ifaof_ifpforaddr_psref(&usrc.sa, ifp, &psref_ia); 678 if (ifa != NULL) 679 ia = ifatoia(ifa); 680 681 /* 682 * Ensure we only send from a valid address. 683 * A NULL address is valid because the packet could be 684 * generated from a packet filter. 685 */ 686 if (ia != NULL && (flags & IP_FORWARDING) == 0 && 687 (error = ip_ifaddrvalid(ia)) != 0) 688 { 689 ARPLOG(LOG_ERR, 690 "refusing to send from invalid address %s (pid %d)\n", 691 ARPLOGADDR(&ip->ip_src), curproc->p_pid); 692 IP_STATINC(IP_STAT_ODROPPED); 693 if (error == 1) 694 /* 695 * Address exists, but is tentative or detached. 696 * We can't send from it because it's invalid, 697 * so we drop the packet. 698 */ 699 error = 0; 700 else 701 error = EADDRNOTAVAIL; 702 goto bad; 703 } 704 705 /* Maybe skip checksums on loopback interfaces. */ 706 if (IN_NEED_CHECKSUM(ifp, M_CSUM_IPv4)) { 707 m->m_pkthdr.csum_flags |= M_CSUM_IPv4; 708 } 709 sw_csum = m->m_pkthdr.csum_flags & ~ifp->if_csum_flags_tx; 710 711 /* Need to fragment the packet */ 712 if (ntohs(ip->ip_len) > mtu && 713 (m->m_pkthdr.csum_flags & M_CSUM_TSOv4) == 0) { 714 goto fragment; 715 } 716 717 #if IFA_STATS 718 if (ia) 719 ia->ia_ifa.ifa_data.ifad_outbytes += ntohs(ip->ip_len); 720 #endif 721 /* 722 * Always initialize the sum to 0! Some HW assisted 723 * checksumming requires this. 724 */ 725 ip->ip_sum = 0; 726 727 if ((m->m_pkthdr.csum_flags & M_CSUM_TSOv4) == 0) { 728 /* 729 * Perform any checksums that the hardware can't do 730 * for us. 731 * 732 * XXX Does any hardware require the {th,uh}_sum 733 * XXX fields to be 0? 734 */ 735 if (sw_csum & M_CSUM_IPv4) { 736 KASSERT(IN_NEED_CHECKSUM(ifp, M_CSUM_IPv4)); 737 ip->ip_sum = in_cksum(m, hlen); 738 m->m_pkthdr.csum_flags &= ~M_CSUM_IPv4; 739 } 740 if (sw_csum & (M_CSUM_TCPv4|M_CSUM_UDPv4)) { 741 if (IN_NEED_CHECKSUM(ifp, 742 sw_csum & (M_CSUM_TCPv4|M_CSUM_UDPv4))) { 743 in_undefer_cksum_tcpudp(m); 744 } 745 m->m_pkthdr.csum_flags &= 746 ~(M_CSUM_TCPv4|M_CSUM_UDPv4); 747 } 748 } 749 750 sa = (m->m_flags & M_MCAST) ? sintocsa(rdst) : sintocsa(dst); 751 752 /* Send it */ 753 if (__predict_false(sw_csum & M_CSUM_TSOv4)) { 754 /* 755 * TSO4 is required by a packet, but disabled for 756 * the interface. 757 */ 758 error = ip_tso_output(ifp, m, sa, rt); 759 } else 760 error = ip_if_output(ifp, m, sa, rt); 761 goto done; 762 763 fragment: 764 /* 765 * We can't use HW checksumming if we're about to fragment the packet. 766 * 767 * XXX Some hardware can do this. 768 */ 769 if (m->m_pkthdr.csum_flags & (M_CSUM_TCPv4|M_CSUM_UDPv4)) { 770 if (IN_NEED_CHECKSUM(ifp, 771 m->m_pkthdr.csum_flags & (M_CSUM_TCPv4|M_CSUM_UDPv4))) { 772 in_undefer_cksum_tcpudp(m); 773 } 774 m->m_pkthdr.csum_flags &= ~(M_CSUM_TCPv4|M_CSUM_UDPv4); 775 } 776 777 /* 778 * Too large for interface; fragment if possible. 779 * Must be able to put at least 8 bytes per fragment. 780 */ 781 if (ntohs(ip->ip_off) & IP_DF) { 782 if (flags & IP_RETURNMTU) { 783 KASSERT(inp != NULL); 784 in4p_errormtu(inp) = mtu; 785 } 786 error = EMSGSIZE; 787 IP_STATINC(IP_STAT_CANTFRAG); 788 goto bad; 789 } 790 791 error = ip_fragment(m, ifp, mtu); 792 if (error) { 793 m = NULL; 794 goto bad; 795 } 796 797 for (; m; m = m0) { 798 m0 = m->m_nextpkt; 799 m->m_nextpkt = NULL; 800 if (error) { 801 m_freem(m); 802 continue; 803 } 804 #if IFA_STATS 805 if (ia) 806 ia->ia_ifa.ifa_data.ifad_outbytes += ntohs(ip->ip_len); 807 #endif 808 /* 809 * If we get there, the packet has not been handled by 810 * IPsec whereas it should have. Now that it has been 811 * fragmented, re-inject it in ip_output so that IPsec 812 * processing can occur. 813 */ 814 if (natt_frag) { 815 error = ip_output(m, opt, NULL, 816 flags | IP_RAWOUTPUT | IP_NOIPNEWID, 817 imo, inp); 818 } else { 819 KASSERT((m->m_pkthdr.csum_flags & 820 (M_CSUM_UDPv4 | M_CSUM_TCPv4)) == 0); 821 error = ip_if_output(ifp, m, (m->m_flags & M_MCAST) ? 822 sintocsa(rdst) : sintocsa(dst), rt); 823 } 824 } 825 if (error == 0) { 826 IP_STATINC(IP_STAT_FRAGMENTED); 827 } 828 829 done: 830 ia4_release(ia, &psref_ia); 831 rtcache_unref(rt, ro); 832 if (ro == &iproute) { 833 rtcache_free(&iproute); 834 } 835 if (mifp != NULL) { 836 if_put(mifp, &psref); 837 } 838 if (bind_need_restore) 839 curlwp_bindx(bound); 840 return error; 841 842 bad: 843 m_freem(m); 844 goto done; 845 } 846 847 int 848 ip_fragment(struct mbuf *m, struct ifnet *ifp, u_long mtu) 849 { 850 struct ip *ip, *mhip; 851 struct mbuf *m0; 852 int len, hlen, off; 853 int mhlen, firstlen; 854 struct mbuf **mnext; 855 int sw_csum = m->m_pkthdr.csum_flags; 856 int fragments = 0; 857 int error = 0; 858 int ipoff, ipflg; 859 860 ip = mtod(m, struct ip *); 861 hlen = ip->ip_hl << 2; 862 863 /* Preserve the offset and flags. */ 864 ipoff = ntohs(ip->ip_off) & IP_OFFMASK; 865 ipflg = ntohs(ip->ip_off) & (IP_RF|IP_DF|IP_MF); 866 867 if (ifp != NULL) 868 sw_csum &= ~ifp->if_csum_flags_tx; 869 870 len = (mtu - hlen) &~ 7; 871 if (len < 8) { 872 IP_STATINC(IP_STAT_CANTFRAG); 873 m_freem(m); 874 return EMSGSIZE; 875 } 876 877 firstlen = len; 878 mnext = &m->m_nextpkt; 879 880 /* 881 * Loop through length of segment after first fragment, 882 * make new header and copy data of each part and link onto chain. 883 */ 884 m0 = m; 885 mhlen = sizeof(struct ip); 886 for (off = hlen + len; off < ntohs(ip->ip_len); off += len) { 887 MGETHDR(m, M_DONTWAIT, MT_HEADER); 888 if (m == NULL) { 889 error = ENOBUFS; 890 IP_STATINC(IP_STAT_ODROPPED); 891 goto sendorfree; 892 } 893 MCLAIM(m, m0->m_owner); 894 895 *mnext = m; 896 mnext = &m->m_nextpkt; 897 898 m->m_data += max_linkhdr; 899 mhip = mtod(m, struct ip *); 900 *mhip = *ip; 901 902 /* we must inherit the flags */ 903 m->m_flags |= m0->m_flags & M_COPYFLAGS; 904 905 if (hlen > sizeof(struct ip)) { 906 mhlen = ip_optcopy(ip, mhip) + sizeof(struct ip); 907 mhip->ip_hl = mhlen >> 2; 908 } 909 m->m_len = mhlen; 910 911 mhip->ip_off = ((off - hlen) >> 3) + ipoff; 912 mhip->ip_off |= ipflg; 913 if (off + len >= ntohs(ip->ip_len)) 914 len = ntohs(ip->ip_len) - off; 915 else 916 mhip->ip_off |= IP_MF; 917 HTONS(mhip->ip_off); 918 919 mhip->ip_len = htons((u_int16_t)(len + mhlen)); 920 m->m_next = m_copym(m0, off, len, M_DONTWAIT); 921 if (m->m_next == NULL) { 922 error = ENOBUFS; 923 IP_STATINC(IP_STAT_ODROPPED); 924 goto sendorfree; 925 } 926 927 m->m_pkthdr.len = mhlen + len; 928 m_reset_rcvif(m); 929 930 mhip->ip_sum = 0; 931 KASSERT((m->m_pkthdr.csum_flags & M_CSUM_IPv4) == 0); 932 if (sw_csum & M_CSUM_IPv4) { 933 mhip->ip_sum = in_cksum(m, mhlen); 934 } else { 935 /* 936 * checksum is hw-offloaded or not necessary. 937 */ 938 m->m_pkthdr.csum_flags |= 939 m0->m_pkthdr.csum_flags & M_CSUM_IPv4; 940 m->m_pkthdr.csum_data |= mhlen << 16; 941 KASSERT(!(ifp != NULL && 942 IN_NEED_CHECKSUM(ifp, M_CSUM_IPv4)) || 943 (m->m_pkthdr.csum_flags & M_CSUM_IPv4) != 0); 944 } 945 IP_STATINC(IP_STAT_OFRAGMENTS); 946 fragments++; 947 } 948 949 /* 950 * Update first fragment by trimming what's been copied out 951 * and updating header, then send each fragment (in order). 952 */ 953 m = m0; 954 m_adj(m, hlen + firstlen - ntohs(ip->ip_len)); 955 m->m_pkthdr.len = hlen + firstlen; 956 ip->ip_len = htons((u_int16_t)m->m_pkthdr.len); 957 ip->ip_off |= htons(IP_MF); 958 ip->ip_sum = 0; 959 if (sw_csum & M_CSUM_IPv4) { 960 ip->ip_sum = in_cksum(m, hlen); 961 m->m_pkthdr.csum_flags &= ~M_CSUM_IPv4; 962 } else { 963 /* 964 * checksum is hw-offloaded or not necessary. 965 */ 966 KASSERT(!(ifp != NULL && IN_NEED_CHECKSUM(ifp, M_CSUM_IPv4)) || 967 (m->m_pkthdr.csum_flags & M_CSUM_IPv4) != 0); 968 KASSERT(M_CSUM_DATA_IPv4_IPHL(m->m_pkthdr.csum_data) >= 969 sizeof(struct ip)); 970 } 971 972 sendorfree: 973 /* 974 * If there is no room for all the fragments, don't queue 975 * any of them. 976 */ 977 if (ifp != NULL) { 978 IFQ_LOCK(&ifp->if_snd); 979 if (ifp->if_snd.ifq_maxlen - ifp->if_snd.ifq_len < fragments && 980 error == 0) { 981 error = ENOBUFS; 982 IP_STATINC(IP_STAT_ODROPPED); 983 IFQ_INC_DROPS(&ifp->if_snd); 984 } 985 IFQ_UNLOCK(&ifp->if_snd); 986 } 987 if (error) { 988 for (m = m0; m; m = m0) { 989 m0 = m->m_nextpkt; 990 m->m_nextpkt = NULL; 991 m_freem(m); 992 } 993 } 994 995 return error; 996 } 997 998 /* 999 * Determine the maximum length of the options to be inserted; 1000 * we would far rather allocate too much space rather than too little. 1001 */ 1002 u_int 1003 ip_optlen(struct inpcb *inp) 1004 { 1005 struct mbuf *m = inp->inp_options; 1006 1007 if (m && m->m_len > offsetof(struct ipoption, ipopt_dst)) { 1008 return (m->m_len - offsetof(struct ipoption, ipopt_dst)); 1009 } 1010 return 0; 1011 } 1012 1013 /* 1014 * Insert IP options into preformed packet. 1015 * Adjust IP destination as required for IP source routing, 1016 * as indicated by a non-zero in_addr at the start of the options. 1017 */ 1018 static struct mbuf * 1019 ip_insertoptions(struct mbuf *m, struct mbuf *opt, int *phlen) 1020 { 1021 struct ipoption *p = mtod(opt, struct ipoption *); 1022 struct mbuf *n; 1023 struct ip *ip = mtod(m, struct ip *); 1024 unsigned optlen; 1025 1026 optlen = opt->m_len - sizeof(p->ipopt_dst); 1027 KASSERT(optlen % 4 == 0); 1028 if (optlen + ntohs(ip->ip_len) > IP_MAXPACKET) 1029 return m; /* XXX should fail */ 1030 if (!in_nullhost(p->ipopt_dst)) 1031 ip->ip_dst = p->ipopt_dst; 1032 if (M_READONLY(m) || M_LEADINGSPACE(m) < optlen) { 1033 MGETHDR(n, M_DONTWAIT, MT_HEADER); 1034 if (n == NULL) 1035 return m; 1036 MCLAIM(n, m->m_owner); 1037 m_move_pkthdr(n, m); 1038 m->m_len -= sizeof(struct ip); 1039 m->m_data += sizeof(struct ip); 1040 n->m_next = m; 1041 n->m_len = optlen + sizeof(struct ip); 1042 n->m_data += max_linkhdr; 1043 memcpy(mtod(n, void *), ip, sizeof(struct ip)); 1044 m = n; 1045 } else { 1046 m->m_data -= optlen; 1047 m->m_len += optlen; 1048 memmove(mtod(m, void *), ip, sizeof(struct ip)); 1049 } 1050 m->m_pkthdr.len += optlen; 1051 ip = mtod(m, struct ip *); 1052 memcpy(ip + 1, p->ipopt_list, optlen); 1053 *phlen = sizeof(struct ip) + optlen; 1054 ip->ip_len = htons(ntohs(ip->ip_len) + optlen); 1055 return m; 1056 } 1057 1058 /* 1059 * Copy options from ipsrc to ipdst, omitting those not copied during 1060 * fragmentation. 1061 */ 1062 int 1063 ip_optcopy(struct ip *ipsrc, struct ip *ipdst) 1064 { 1065 u_char *cp, *dp; 1066 int opt, optlen, cnt; 1067 1068 cp = (u_char *)(ipsrc + 1); 1069 dp = (u_char *)(ipdst + 1); 1070 cnt = (ipsrc->ip_hl << 2) - sizeof(struct ip); 1071 for (; cnt > 0; cnt -= optlen, cp += optlen) { 1072 opt = cp[0]; 1073 if (opt == IPOPT_EOL) 1074 break; 1075 if (opt == IPOPT_NOP) { 1076 /* Preserve for IP mcast tunnel's LSRR alignment. */ 1077 *dp++ = IPOPT_NOP; 1078 optlen = 1; 1079 continue; 1080 } 1081 1082 KASSERT(cnt >= IPOPT_OLEN + sizeof(*cp)); 1083 optlen = cp[IPOPT_OLEN]; 1084 KASSERT(optlen >= IPOPT_OLEN + sizeof(*cp) && optlen < cnt); 1085 1086 /* Invalid lengths should have been caught by ip_dooptions. */ 1087 if (optlen > cnt) 1088 optlen = cnt; 1089 if (IPOPT_COPIED(opt)) { 1090 bcopy((void *)cp, (void *)dp, (unsigned)optlen); 1091 dp += optlen; 1092 } 1093 } 1094 1095 for (optlen = dp - (u_char *)(ipdst+1); optlen & 0x3; optlen++) { 1096 *dp++ = IPOPT_EOL; 1097 } 1098 1099 return optlen; 1100 } 1101 1102 /* 1103 * IP socket option processing. 1104 */ 1105 int 1106 ip_ctloutput(int op, struct socket *so, struct sockopt *sopt) 1107 { 1108 struct inpcb *inp = sotoinpcb(so); 1109 struct ip *ip = &in4p_ip(inp); 1110 int inpflags = inp->inp_flags; 1111 int optval = 0, error = 0; 1112 struct in_pktinfo pktinfo; 1113 1114 KASSERT(solocked(so)); 1115 1116 if (sopt->sopt_level != IPPROTO_IP) { 1117 if (sopt->sopt_level == SOL_SOCKET && sopt->sopt_name == SO_NOHEADER) 1118 return 0; 1119 return ENOPROTOOPT; 1120 } 1121 1122 switch (op) { 1123 case PRCO_SETOPT: 1124 switch (sopt->sopt_name) { 1125 case IP_OPTIONS: 1126 #ifdef notyet 1127 case IP_RETOPTS: 1128 #endif 1129 error = ip_pcbopts(inp, sopt); 1130 break; 1131 1132 case IP_TOS: 1133 case IP_TTL: 1134 case IP_MINTTL: 1135 case IP_RECVOPTS: 1136 case IP_RECVRETOPTS: 1137 case IP_RECVDSTADDR: 1138 case IP_RECVIF: 1139 case IP_RECVPKTINFO: 1140 case IP_RECVTTL: 1141 case IP_BINDANY: 1142 error = sockopt_getint(sopt, &optval); 1143 if (error) 1144 break; 1145 1146 switch (sopt->sopt_name) { 1147 case IP_TOS: 1148 ip->ip_tos = optval; 1149 break; 1150 1151 case IP_TTL: 1152 ip->ip_ttl = optval; 1153 break; 1154 1155 case IP_MINTTL: 1156 if (optval > 0 && optval <= MAXTTL) 1157 in4p_ip_minttl(inp) = optval; 1158 else 1159 error = EINVAL; 1160 break; 1161 #define OPTSET(bit) \ 1162 if (optval) \ 1163 inpflags |= bit; \ 1164 else \ 1165 inpflags &= ~bit; 1166 1167 case IP_RECVOPTS: 1168 OPTSET(INP_RECVOPTS); 1169 break; 1170 1171 case IP_RECVPKTINFO: 1172 OPTSET(INP_RECVPKTINFO); 1173 break; 1174 1175 case IP_RECVRETOPTS: 1176 OPTSET(INP_RECVRETOPTS); 1177 break; 1178 1179 case IP_RECVDSTADDR: 1180 OPTSET(INP_RECVDSTADDR); 1181 break; 1182 1183 case IP_RECVIF: 1184 OPTSET(INP_RECVIF); 1185 break; 1186 1187 case IP_RECVTTL: 1188 OPTSET(INP_RECVTTL); 1189 break; 1190 1191 case IP_BINDANY: 1192 error = kauth_authorize_network( 1193 kauth_cred_get(), KAUTH_NETWORK_BIND, 1194 KAUTH_REQ_NETWORK_BIND_ANYADDR, so, 1195 NULL, NULL); 1196 if (error == 0) { 1197 OPTSET(INP_BINDANY); 1198 } 1199 break; 1200 } 1201 break; 1202 case IP_PKTINFO: 1203 error = sockopt_getint(sopt, &optval); 1204 if (!error) { 1205 /* Linux compatibility */ 1206 OPTSET(INP_RECVPKTINFO); 1207 break; 1208 } 1209 error = sockopt_get(sopt, &pktinfo, sizeof(pktinfo)); 1210 if (error) 1211 break; 1212 1213 if (pktinfo.ipi_ifindex == 0) { 1214 in4p_prefsrcip(inp) = pktinfo.ipi_addr; 1215 break; 1216 } 1217 1218 /* Solaris compatibility */ 1219 struct ifnet *ifp; 1220 struct in_ifaddr *ia; 1221 int s; 1222 1223 /* pick up primary address */ 1224 s = pserialize_read_enter(); 1225 ifp = if_byindex(pktinfo.ipi_ifindex); 1226 if (ifp == NULL) { 1227 pserialize_read_exit(s); 1228 error = EADDRNOTAVAIL; 1229 break; 1230 } 1231 ia = in_get_ia_from_ifp(ifp); 1232 if (ia == NULL) { 1233 pserialize_read_exit(s); 1234 error = EADDRNOTAVAIL; 1235 break; 1236 } 1237 in4p_prefsrcip(inp) = IA_SIN(ia)->sin_addr; 1238 pserialize_read_exit(s); 1239 break; 1240 break; 1241 #undef OPTSET 1242 1243 case IP_MULTICAST_IF: 1244 case IP_MULTICAST_TTL: 1245 case IP_MULTICAST_LOOP: 1246 case IP_ADD_MEMBERSHIP: 1247 case IP_DROP_MEMBERSHIP: 1248 error = ip_setmoptions(&inp->inp_moptions, sopt); 1249 break; 1250 1251 case IP_PORTRANGE: 1252 error = sockopt_getint(sopt, &optval); 1253 if (error) 1254 break; 1255 1256 switch (optval) { 1257 case IP_PORTRANGE_DEFAULT: 1258 case IP_PORTRANGE_HIGH: 1259 inpflags &= ~(INP_LOWPORT); 1260 break; 1261 1262 case IP_PORTRANGE_LOW: 1263 inpflags |= INP_LOWPORT; 1264 break; 1265 1266 default: 1267 error = EINVAL; 1268 break; 1269 } 1270 break; 1271 1272 case IP_PORTALGO: 1273 error = sockopt_getint(sopt, &optval); 1274 if (error) 1275 break; 1276 1277 error = portalgo_algo_index_select(inp, optval); 1278 break; 1279 1280 #if defined(IPSEC) 1281 case IP_IPSEC_POLICY: 1282 if (ipsec_enabled) { 1283 error = ipsec_set_policy(inp, 1284 sopt->sopt_data, sopt->sopt_size, 1285 curlwp->l_cred); 1286 } else 1287 error = ENOPROTOOPT; 1288 break; 1289 #endif /* IPSEC */ 1290 1291 default: 1292 error = ENOPROTOOPT; 1293 break; 1294 } 1295 break; 1296 1297 case PRCO_GETOPT: 1298 switch (sopt->sopt_name) { 1299 case IP_OPTIONS: 1300 case IP_RETOPTS: { 1301 struct mbuf *mopts = inp->inp_options; 1302 1303 if (mopts) { 1304 struct mbuf *m; 1305 1306 m = m_copym(mopts, 0, M_COPYALL, M_DONTWAIT); 1307 if (m == NULL) { 1308 error = ENOBUFS; 1309 break; 1310 } 1311 error = sockopt_setmbuf(sopt, m); 1312 } 1313 break; 1314 } 1315 case IP_TOS: 1316 case IP_TTL: 1317 case IP_MINTTL: 1318 case IP_RECVOPTS: 1319 case IP_RECVRETOPTS: 1320 case IP_RECVDSTADDR: 1321 case IP_RECVIF: 1322 case IP_RECVPKTINFO: 1323 case IP_RECVTTL: 1324 case IP_ERRORMTU: 1325 case IP_BINDANY: 1326 switch (sopt->sopt_name) { 1327 case IP_TOS: 1328 optval = ip->ip_tos; 1329 break; 1330 1331 case IP_TTL: 1332 optval = ip->ip_ttl; 1333 break; 1334 1335 case IP_MINTTL: 1336 optval = in4p_ip_minttl(inp); 1337 break; 1338 1339 case IP_ERRORMTU: 1340 optval = in4p_errormtu(inp); 1341 break; 1342 1343 #define OPTBIT(bit) (inpflags & bit ? 1 : 0) 1344 1345 case IP_RECVOPTS: 1346 optval = OPTBIT(INP_RECVOPTS); 1347 break; 1348 1349 case IP_RECVPKTINFO: 1350 optval = OPTBIT(INP_RECVPKTINFO); 1351 break; 1352 1353 case IP_RECVRETOPTS: 1354 optval = OPTBIT(INP_RECVRETOPTS); 1355 break; 1356 1357 case IP_RECVDSTADDR: 1358 optval = OPTBIT(INP_RECVDSTADDR); 1359 break; 1360 1361 case IP_RECVIF: 1362 optval = OPTBIT(INP_RECVIF); 1363 break; 1364 1365 case IP_RECVTTL: 1366 optval = OPTBIT(INP_RECVTTL); 1367 break; 1368 1369 case IP_BINDANY: 1370 optval = OPTBIT(INP_BINDANY); 1371 break; 1372 } 1373 error = sockopt_setint(sopt, optval); 1374 break; 1375 1376 case IP_PKTINFO: 1377 switch (sopt->sopt_size) { 1378 case sizeof(int): 1379 /* Linux compatibility */ 1380 optval = OPTBIT(INP_RECVPKTINFO); 1381 error = sockopt_setint(sopt, optval); 1382 break; 1383 case sizeof(struct in_pktinfo): 1384 /* Solaris compatibility */ 1385 pktinfo.ipi_ifindex = 0; 1386 pktinfo.ipi_addr = in4p_prefsrcip(inp); 1387 error = sockopt_set(sopt, &pktinfo, 1388 sizeof(pktinfo)); 1389 break; 1390 default: 1391 /* 1392 * While size is stuck at 0, and, later, if 1393 * the caller doesn't use an exactly sized 1394 * recipient for the data, default to Linux 1395 * compatibility 1396 */ 1397 optval = OPTBIT(INP_RECVPKTINFO); 1398 error = sockopt_setint(sopt, optval); 1399 break; 1400 } 1401 break; 1402 1403 #if 0 /* defined(IPSEC) */ 1404 case IP_IPSEC_POLICY: 1405 { 1406 struct mbuf *m = NULL; 1407 1408 /* XXX this will return EINVAL as sopt is empty */ 1409 error = ipsec_get_policy(inp, sopt->sopt_data, 1410 sopt->sopt_size, &m); 1411 if (error == 0) 1412 error = sockopt_setmbuf(sopt, m); 1413 break; 1414 } 1415 #endif /*IPSEC*/ 1416 1417 case IP_MULTICAST_IF: 1418 case IP_MULTICAST_TTL: 1419 case IP_MULTICAST_LOOP: 1420 case IP_ADD_MEMBERSHIP: 1421 case IP_DROP_MEMBERSHIP: 1422 error = ip_getmoptions(inp->inp_moptions, sopt); 1423 break; 1424 1425 case IP_PORTRANGE: 1426 if (inpflags & INP_LOWPORT) 1427 optval = IP_PORTRANGE_LOW; 1428 else 1429 optval = IP_PORTRANGE_DEFAULT; 1430 error = sockopt_setint(sopt, optval); 1431 break; 1432 1433 case IP_PORTALGO: 1434 optval = inp->inp_portalgo; 1435 error = sockopt_setint(sopt, optval); 1436 break; 1437 1438 default: 1439 error = ENOPROTOOPT; 1440 break; 1441 } 1442 break; 1443 } 1444 1445 if (!error) { 1446 inp->inp_flags = inpflags; 1447 } 1448 return error; 1449 } 1450 1451 static int 1452 ip_pktinfo_prepare(const struct inpcb *inp, const struct in_pktinfo *pktinfo, 1453 struct ip_pktopts *pktopts, int *flags, kauth_cred_t cred) 1454 { 1455 struct ip_moptions *imo; 1456 int error = 0; 1457 bool addrset = false; 1458 1459 if (!in_nullhost(pktinfo->ipi_addr)) { 1460 pktopts->ippo_laddr.sin_addr = pktinfo->ipi_addr; 1461 /* EADDRNOTAVAIL? */ 1462 error = inpcb_bindableaddr(inp, &pktopts->ippo_laddr, cred); 1463 if (error != 0) 1464 return error; 1465 addrset = true; 1466 } 1467 1468 if (pktinfo->ipi_ifindex != 0) { 1469 if (!addrset) { 1470 struct ifnet *ifp; 1471 struct in_ifaddr *ia; 1472 int s; 1473 1474 /* pick up primary address */ 1475 s = pserialize_read_enter(); 1476 ifp = if_byindex(pktinfo->ipi_ifindex); 1477 if (ifp == NULL) { 1478 pserialize_read_exit(s); 1479 return EADDRNOTAVAIL; 1480 } 1481 ia = in_get_ia_from_ifp(ifp); 1482 if (ia == NULL) { 1483 pserialize_read_exit(s); 1484 return EADDRNOTAVAIL; 1485 } 1486 pktopts->ippo_laddr.sin_addr = IA_SIN(ia)->sin_addr; 1487 pserialize_read_exit(s); 1488 } 1489 1490 /* 1491 * If specified ipi_ifindex, 1492 * use copied or locally initialized ip_moptions. 1493 * Original ip_moptions must not be modified. 1494 */ 1495 imo = &pktopts->ippo_imobuf; /* local buf in pktopts */ 1496 if (pktopts->ippo_imo != NULL) { 1497 memcpy(imo, pktopts->ippo_imo, sizeof(*imo)); 1498 } else { 1499 memset(imo, 0, sizeof(*imo)); 1500 imo->imo_multicast_ttl = IP_DEFAULT_MULTICAST_TTL; 1501 imo->imo_multicast_loop = IP_DEFAULT_MULTICAST_LOOP; 1502 } 1503 imo->imo_multicast_if_index = pktinfo->ipi_ifindex; 1504 pktopts->ippo_imo = imo; 1505 *flags |= IP_ROUTETOIFINDEX; 1506 } 1507 return error; 1508 } 1509 1510 /* 1511 * Set up IP outgoing packet options. Even if control is NULL, 1512 * pktopts->ippo_laddr and pktopts->ippo_imo are set and used. 1513 */ 1514 int 1515 ip_setpktopts(struct mbuf *control, struct ip_pktopts *pktopts, int *flags, 1516 struct inpcb *inp, kauth_cred_t cred) 1517 { 1518 struct cmsghdr *cm; 1519 struct in_pktinfo pktinfo; 1520 int error; 1521 1522 pktopts->ippo_imo = inp->inp_moptions; 1523 1524 struct in_addr *ia = in_nullhost(in4p_prefsrcip(inp)) ? &in4p_laddr(inp) : 1525 &in4p_prefsrcip(inp); 1526 sockaddr_in_init(&pktopts->ippo_laddr, ia, 0); 1527 1528 if (control == NULL) 1529 return 0; 1530 1531 /* 1532 * XXX: Currently, we assume all the optional information is 1533 * stored in a single mbuf. 1534 */ 1535 if (control->m_next) 1536 return EINVAL; 1537 1538 for (; control->m_len > 0; 1539 control->m_data += CMSG_ALIGN(cm->cmsg_len), 1540 control->m_len -= CMSG_ALIGN(cm->cmsg_len)) { 1541 cm = mtod(control, struct cmsghdr *); 1542 if ((control->m_len < sizeof(*cm)) || 1543 (cm->cmsg_len == 0) || 1544 (cm->cmsg_len > control->m_len)) { 1545 return EINVAL; 1546 } 1547 if (cm->cmsg_level != IPPROTO_IP) 1548 continue; 1549 1550 switch (cm->cmsg_type) { 1551 case IP_PKTINFO: 1552 if (cm->cmsg_len != CMSG_LEN(sizeof(pktinfo))) 1553 return EINVAL; 1554 memcpy(&pktinfo, CMSG_DATA(cm), sizeof(pktinfo)); 1555 error = ip_pktinfo_prepare(inp, &pktinfo, pktopts, 1556 flags, cred); 1557 if (error) 1558 return error; 1559 break; 1560 case IP_SENDSRCADDR: /* FreeBSD compatibility */ 1561 if (cm->cmsg_len != CMSG_LEN(sizeof(struct in_addr))) 1562 return EINVAL; 1563 pktinfo.ipi_ifindex = 0; 1564 pktinfo.ipi_addr = 1565 ((struct in_pktinfo *)CMSG_DATA(cm))->ipi_addr; 1566 error = ip_pktinfo_prepare(inp, &pktinfo, pktopts, 1567 flags, cred); 1568 if (error) 1569 return error; 1570 break; 1571 default: 1572 return ENOPROTOOPT; 1573 } 1574 } 1575 return 0; 1576 } 1577 1578 /* 1579 * Set up IP options in pcb for insertion in output packets. 1580 * Store in mbuf with pointer in pcbopt, adding pseudo-option 1581 * with destination address if source routed. 1582 */ 1583 static int 1584 ip_pcbopts(struct inpcb *inp, const struct sockopt *sopt) 1585 { 1586 struct mbuf *m; 1587 const u_char *cp; 1588 u_char *dp; 1589 int cnt; 1590 1591 KASSERT(inp_locked(inp)); 1592 1593 /* Turn off any old options. */ 1594 if (inp->inp_options) { 1595 m_free(inp->inp_options); 1596 } 1597 inp->inp_options = NULL; 1598 if ((cnt = sopt->sopt_size) == 0) { 1599 /* Only turning off any previous options. */ 1600 return 0; 1601 } 1602 cp = sopt->sopt_data; 1603 1604 if (cnt % 4) { 1605 /* Must be 4-byte aligned, because there's no padding. */ 1606 return EINVAL; 1607 } 1608 1609 m = m_get(M_DONTWAIT, MT_SOOPTS); 1610 if (m == NULL) 1611 return ENOBUFS; 1612 1613 dp = mtod(m, u_char *); 1614 memset(dp, 0, sizeof(struct in_addr)); 1615 dp += sizeof(struct in_addr); 1616 m->m_len = sizeof(struct in_addr); 1617 1618 /* 1619 * IP option list according to RFC791. Each option is of the form 1620 * 1621 * [optval] [olen] [(olen - 2) data bytes] 1622 * 1623 * We validate the list and copy options to an mbuf for prepending 1624 * to data packets. The IP first-hop destination address will be 1625 * stored before actual options and is zero if unset. 1626 */ 1627 while (cnt > 0) { 1628 uint8_t optval, olen, offset; 1629 1630 optval = cp[IPOPT_OPTVAL]; 1631 1632 if (optval == IPOPT_EOL || optval == IPOPT_NOP) { 1633 olen = 1; 1634 } else { 1635 if (cnt < IPOPT_OLEN + 1) 1636 goto bad; 1637 1638 olen = cp[IPOPT_OLEN]; 1639 if (olen < IPOPT_OLEN + 1 || olen > cnt) 1640 goto bad; 1641 } 1642 1643 if (optval == IPOPT_LSRR || optval == IPOPT_SSRR) { 1644 /* 1645 * user process specifies route as: 1646 * ->A->B->C->D 1647 * D must be our final destination (but we can't 1648 * check that since we may not have connected yet). 1649 * A is first hop destination, which doesn't appear in 1650 * actual IP option, but is stored before the options. 1651 */ 1652 if (olen < IPOPT_OFFSET + 1 + sizeof(struct in_addr)) 1653 goto bad; 1654 1655 offset = cp[IPOPT_OFFSET]; 1656 memcpy(mtod(m, u_char *), cp + IPOPT_OFFSET + 1, 1657 sizeof(struct in_addr)); 1658 1659 cp += sizeof(struct in_addr); 1660 cnt -= sizeof(struct in_addr); 1661 olen -= sizeof(struct in_addr); 1662 1663 if (m->m_len + olen > MAX_IPOPTLEN + sizeof(struct in_addr)) 1664 goto bad; 1665 1666 memcpy(dp, cp, olen); 1667 dp[IPOPT_OPTVAL] = optval; 1668 dp[IPOPT_OLEN] = olen; 1669 dp[IPOPT_OFFSET] = offset; 1670 break; 1671 } else { 1672 if (m->m_len + olen > MAX_IPOPTLEN + sizeof(struct in_addr)) 1673 goto bad; 1674 1675 memcpy(dp, cp, olen); 1676 break; 1677 } 1678 1679 dp += olen; 1680 m->m_len += olen; 1681 1682 if (optval == IPOPT_EOL) 1683 break; 1684 1685 cp += olen; 1686 cnt -= olen; 1687 } 1688 1689 inp->inp_options = m; 1690 return 0; 1691 1692 bad: 1693 (void)m_free(m); 1694 return EINVAL; 1695 } 1696 1697 /* 1698 * following RFC1724 section 3.3, 0.0.0.0/8 is interpreted as interface index. 1699 * Must be called in a pserialize critical section. 1700 */ 1701 static struct ifnet * 1702 ip_multicast_if(struct in_addr *a, int *ifindexp) 1703 { 1704 int ifindex; 1705 struct ifnet *ifp = NULL; 1706 struct in_ifaddr *ia; 1707 1708 if (ifindexp) 1709 *ifindexp = 0; 1710 if (ntohl(a->s_addr) >> 24 == 0) { 1711 ifindex = ntohl(a->s_addr) & 0xffffff; 1712 ifp = if_byindex(ifindex); 1713 if (!ifp) 1714 return NULL; 1715 if (ifindexp) 1716 *ifindexp = ifindex; 1717 } else { 1718 IN_ADDRHASH_READER_FOREACH(ia, a->s_addr) { 1719 if (in_hosteq(ia->ia_addr.sin_addr, *a) && 1720 (ia->ia_ifp->if_flags & IFF_MULTICAST) != 0) { 1721 ifp = ia->ia_ifp; 1722 if (if_is_deactivated(ifp)) 1723 ifp = NULL; 1724 break; 1725 } 1726 } 1727 } 1728 return ifp; 1729 } 1730 1731 static int 1732 ip_getoptval(const struct sockopt *sopt, u_int8_t *val, u_int maxval) 1733 { 1734 u_int tval; 1735 u_char cval; 1736 int error; 1737 1738 if (sopt == NULL) 1739 return EINVAL; 1740 1741 switch (sopt->sopt_size) { 1742 case sizeof(u_char): 1743 error = sockopt_get(sopt, &cval, sizeof(u_char)); 1744 tval = cval; 1745 break; 1746 1747 case sizeof(u_int): 1748 error = sockopt_get(sopt, &tval, sizeof(u_int)); 1749 break; 1750 1751 default: 1752 error = EINVAL; 1753 } 1754 1755 if (error) 1756 return error; 1757 1758 if (tval > maxval) 1759 return EINVAL; 1760 1761 *val = tval; 1762 return 0; 1763 } 1764 1765 static int 1766 ip_get_membership(const struct sockopt *sopt, struct ifnet **ifp, 1767 struct psref *psref, struct in_addr *ia, bool add) 1768 { 1769 int error; 1770 struct ip_mreq mreq; 1771 1772 error = sockopt_get(sopt, &mreq, sizeof(mreq)); 1773 if (error) 1774 return error; 1775 1776 if (!IN_MULTICAST(mreq.imr_multiaddr.s_addr)) 1777 return EINVAL; 1778 1779 memcpy(ia, &mreq.imr_multiaddr, sizeof(*ia)); 1780 1781 if (in_nullhost(mreq.imr_interface)) { 1782 union { 1783 struct sockaddr dst; 1784 struct sockaddr_in dst4; 1785 } u; 1786 struct route ro; 1787 1788 if (!add) { 1789 *ifp = NULL; 1790 return 0; 1791 } 1792 /* 1793 * If no interface address was provided, use the interface of 1794 * the route to the given multicast address. 1795 */ 1796 struct rtentry *rt; 1797 memset(&ro, 0, sizeof(ro)); 1798 1799 sockaddr_in_init(&u.dst4, ia, 0); 1800 error = rtcache_setdst(&ro, &u.dst); 1801 if (error != 0) 1802 return error; 1803 *ifp = (rt = rtcache_init(&ro)) != NULL ? rt->rt_ifp : NULL; 1804 if (*ifp != NULL) { 1805 if (if_is_deactivated(*ifp)) 1806 *ifp = NULL; 1807 else 1808 if_acquire(*ifp, psref); 1809 } 1810 rtcache_unref(rt, &ro); 1811 rtcache_free(&ro); 1812 } else { 1813 int s = pserialize_read_enter(); 1814 *ifp = ip_multicast_if(&mreq.imr_interface, NULL); 1815 if (!add && *ifp == NULL) { 1816 pserialize_read_exit(s); 1817 return EADDRNOTAVAIL; 1818 } 1819 if (*ifp != NULL) { 1820 if (if_is_deactivated(*ifp)) 1821 *ifp = NULL; 1822 else 1823 if_acquire(*ifp, psref); 1824 } 1825 pserialize_read_exit(s); 1826 } 1827 return 0; 1828 } 1829 1830 /* 1831 * Add a multicast group membership. 1832 * Group must be a valid IP multicast address. 1833 */ 1834 static int 1835 ip_add_membership(struct ip_moptions *imo, const struct sockopt *sopt) 1836 { 1837 struct ifnet *ifp = NULL; // XXX: gcc [ppc] 1838 struct in_addr ia; 1839 int i, error, bound; 1840 struct psref psref; 1841 1842 /* imo is protected by solock or referenced only by the caller */ 1843 1844 bound = curlwp_bind(); 1845 if (sopt->sopt_size == sizeof(struct ip_mreq)) 1846 error = ip_get_membership(sopt, &ifp, &psref, &ia, true); 1847 else { 1848 #ifdef INET6 1849 error = ip6_get_membership(sopt, &ifp, &psref, &ia, sizeof(ia)); 1850 #else 1851 error = EINVAL; 1852 #endif 1853 } 1854 1855 if (error) 1856 goto out; 1857 1858 /* 1859 * See if we found an interface, and confirm that it 1860 * supports multicast. 1861 */ 1862 if (ifp == NULL || (ifp->if_flags & IFF_MULTICAST) == 0) { 1863 error = EADDRNOTAVAIL; 1864 goto out; 1865 } 1866 1867 /* 1868 * See if the membership already exists or if all the 1869 * membership slots are full. 1870 */ 1871 for (i = 0; i < imo->imo_num_memberships; ++i) { 1872 if (imo->imo_membership[i]->inm_ifp == ifp && 1873 in_hosteq(imo->imo_membership[i]->inm_addr, ia)) 1874 break; 1875 } 1876 if (i < imo->imo_num_memberships) { 1877 error = EADDRINUSE; 1878 goto out; 1879 } 1880 1881 if (i == IP_MAX_MEMBERSHIPS) { 1882 error = ETOOMANYREFS; 1883 goto out; 1884 } 1885 1886 /* 1887 * Everything looks good; add a new record to the multicast 1888 * address list for the given interface. 1889 */ 1890 imo->imo_membership[i] = in_addmulti(&ia, ifp); 1891 if (imo->imo_membership[i] == NULL) { 1892 error = ENOBUFS; 1893 goto out; 1894 } 1895 1896 ++imo->imo_num_memberships; 1897 error = 0; 1898 out: 1899 if_put(ifp, &psref); 1900 curlwp_bindx(bound); 1901 return error; 1902 } 1903 1904 /* 1905 * Drop a multicast group membership. 1906 * Group must be a valid IP multicast address. 1907 */ 1908 static int 1909 ip_drop_membership(struct ip_moptions *imo, const struct sockopt *sopt) 1910 { 1911 struct in_addr ia = { .s_addr = 0 }; // XXX: gcc [ppc] 1912 struct ifnet *ifp = NULL; // XXX: gcc [ppc] 1913 int i, error, bound; 1914 struct psref psref; 1915 1916 /* imo is protected by solock or referenced only by the caller */ 1917 1918 bound = curlwp_bind(); 1919 if (sopt->sopt_size == sizeof(struct ip_mreq)) 1920 error = ip_get_membership(sopt, &ifp, &psref, &ia, false); 1921 else { 1922 #ifdef INET6 1923 error = ip6_get_membership(sopt, &ifp, &psref, &ia, sizeof(ia)); 1924 #else 1925 error = EINVAL; 1926 #endif 1927 } 1928 1929 if (error) 1930 goto out; 1931 1932 /* 1933 * Find the membership in the membership array. 1934 */ 1935 for (i = 0; i < imo->imo_num_memberships; ++i) { 1936 if ((ifp == NULL || 1937 imo->imo_membership[i]->inm_ifp == ifp) && 1938 in_hosteq(imo->imo_membership[i]->inm_addr, ia)) 1939 break; 1940 } 1941 if (i == imo->imo_num_memberships) { 1942 error = EADDRNOTAVAIL; 1943 goto out; 1944 } 1945 1946 /* 1947 * Give up the multicast address record to which the 1948 * membership points. 1949 */ 1950 in_delmulti(imo->imo_membership[i]); 1951 1952 /* 1953 * Remove the gap in the membership array. 1954 */ 1955 for (++i; i < imo->imo_num_memberships; ++i) 1956 imo->imo_membership[i-1] = imo->imo_membership[i]; 1957 --imo->imo_num_memberships; 1958 error = 0; 1959 out: 1960 if_put(ifp, &psref); 1961 curlwp_bindx(bound); 1962 return error; 1963 } 1964 1965 /* 1966 * Set the IP multicast options in response to user setsockopt(). 1967 */ 1968 int 1969 ip_setmoptions(struct ip_moptions **pimo, const struct sockopt *sopt) 1970 { 1971 struct ip_moptions *imo = *pimo; 1972 struct in_addr addr; 1973 struct ifnet *ifp; 1974 int ifindex, error = 0; 1975 1976 /* The passed imo isn't NULL, it should be protected by solock */ 1977 1978 if (!imo) { 1979 /* 1980 * No multicast option buffer attached to the pcb; 1981 * allocate one and initialize to default values. 1982 */ 1983 imo = kmem_intr_alloc(sizeof(*imo), KM_NOSLEEP); 1984 if (imo == NULL) 1985 return ENOBUFS; 1986 1987 imo->imo_multicast_if_index = 0; 1988 imo->imo_multicast_addr.s_addr = INADDR_ANY; 1989 imo->imo_multicast_ttl = IP_DEFAULT_MULTICAST_TTL; 1990 imo->imo_multicast_loop = IP_DEFAULT_MULTICAST_LOOP; 1991 imo->imo_num_memberships = 0; 1992 *pimo = imo; 1993 } 1994 1995 switch (sopt->sopt_name) { 1996 case IP_MULTICAST_IF: { 1997 int s; 1998 /* 1999 * Select the interface for outgoing multicast packets. 2000 */ 2001 error = sockopt_get(sopt, &addr, sizeof(addr)); 2002 if (error) 2003 break; 2004 2005 /* 2006 * INADDR_ANY is used to remove a previous selection. 2007 * When no interface is selected, a default one is 2008 * chosen every time a multicast packet is sent. 2009 */ 2010 if (in_nullhost(addr)) { 2011 imo->imo_multicast_if_index = 0; 2012 break; 2013 } 2014 /* 2015 * The selected interface is identified by its local 2016 * IP address. Find the interface and confirm that 2017 * it supports multicasting. 2018 */ 2019 s = pserialize_read_enter(); 2020 ifp = ip_multicast_if(&addr, &ifindex); 2021 if (ifp == NULL || (ifp->if_flags & IFF_MULTICAST) == 0) { 2022 pserialize_read_exit(s); 2023 error = EADDRNOTAVAIL; 2024 break; 2025 } 2026 imo->imo_multicast_if_index = ifp->if_index; 2027 pserialize_read_exit(s); 2028 if (ifindex) 2029 imo->imo_multicast_addr = addr; 2030 else 2031 imo->imo_multicast_addr.s_addr = INADDR_ANY; 2032 break; 2033 } 2034 2035 case IP_MULTICAST_TTL: 2036 /* 2037 * Set the IP time-to-live for outgoing multicast packets. 2038 */ 2039 error = ip_getoptval(sopt, &imo->imo_multicast_ttl, MAXTTL); 2040 break; 2041 2042 case IP_MULTICAST_LOOP: 2043 /* 2044 * Set the loopback flag for outgoing multicast packets. 2045 * Must be zero or one. 2046 */ 2047 error = ip_getoptval(sopt, &imo->imo_multicast_loop, 1); 2048 break; 2049 2050 case IP_ADD_MEMBERSHIP: /* IPV6_JOIN_GROUP */ 2051 error = ip_add_membership(imo, sopt); 2052 break; 2053 2054 case IP_DROP_MEMBERSHIP: /* IPV6_LEAVE_GROUP */ 2055 error = ip_drop_membership(imo, sopt); 2056 break; 2057 2058 default: 2059 error = EOPNOTSUPP; 2060 break; 2061 } 2062 2063 /* 2064 * If all options have default values, no need to keep the mbuf. 2065 */ 2066 if (imo->imo_multicast_if_index == 0 && 2067 imo->imo_multicast_ttl == IP_DEFAULT_MULTICAST_TTL && 2068 imo->imo_multicast_loop == IP_DEFAULT_MULTICAST_LOOP && 2069 imo->imo_num_memberships == 0) { 2070 kmem_intr_free(imo, sizeof(*imo)); 2071 *pimo = NULL; 2072 } 2073 2074 return error; 2075 } 2076 2077 /* 2078 * Return the IP multicast options in response to user getsockopt(). 2079 */ 2080 int 2081 ip_getmoptions(struct ip_moptions *imo, struct sockopt *sopt) 2082 { 2083 struct in_addr addr; 2084 uint8_t optval; 2085 int error = 0; 2086 2087 /* imo is protected by solock or referenced only by the caller */ 2088 2089 switch (sopt->sopt_name) { 2090 case IP_MULTICAST_IF: 2091 if (imo == NULL || imo->imo_multicast_if_index == 0) 2092 addr = zeroin_addr; 2093 else if (imo->imo_multicast_addr.s_addr) { 2094 /* return the value user has set */ 2095 addr = imo->imo_multicast_addr; 2096 } else { 2097 struct ifnet *ifp; 2098 struct in_ifaddr *ia = NULL; 2099 int s = pserialize_read_enter(); 2100 2101 ifp = if_byindex(imo->imo_multicast_if_index); 2102 if (ifp != NULL) { 2103 ia = in_get_ia_from_ifp(ifp); 2104 } 2105 addr = ia ? ia->ia_addr.sin_addr : zeroin_addr; 2106 pserialize_read_exit(s); 2107 } 2108 error = sockopt_set(sopt, &addr, sizeof(addr)); 2109 break; 2110 2111 case IP_MULTICAST_TTL: 2112 optval = imo ? imo->imo_multicast_ttl 2113 : IP_DEFAULT_MULTICAST_TTL; 2114 2115 error = sockopt_set(sopt, &optval, sizeof(optval)); 2116 break; 2117 2118 case IP_MULTICAST_LOOP: 2119 optval = imo ? imo->imo_multicast_loop 2120 : IP_DEFAULT_MULTICAST_LOOP; 2121 2122 error = sockopt_set(sopt, &optval, sizeof(optval)); 2123 break; 2124 2125 default: 2126 error = EOPNOTSUPP; 2127 } 2128 2129 return error; 2130 } 2131 2132 /* 2133 * Discard the IP multicast options. 2134 */ 2135 void 2136 ip_freemoptions(struct ip_moptions *imo) 2137 { 2138 int i; 2139 2140 /* The owner of imo (inp) should be protected by solock */ 2141 2142 if (imo != NULL) { 2143 for (i = 0; i < imo->imo_num_memberships; ++i) { 2144 struct in_multi *inm = imo->imo_membership[i]; 2145 in_delmulti(inm); 2146 /* ifp should not leave thanks to solock */ 2147 } 2148 2149 kmem_intr_free(imo, sizeof(*imo)); 2150 } 2151 } 2152 2153 /* 2154 * Routine called from ip_output() to loop back a copy of an IP multicast 2155 * packet to the input queue of a specified interface. Note that this 2156 * calls the output routine of the loopback "driver", but with an interface 2157 * pointer that might NOT be lo0ifp -- easier than replicating that code here. 2158 */ 2159 static void 2160 ip_mloopback(struct ifnet *ifp, struct mbuf *m, const struct sockaddr_in *dst) 2161 { 2162 struct ip *ip; 2163 struct mbuf *copym; 2164 2165 copym = m_copypacket(m, M_DONTWAIT); 2166 if (copym != NULL && 2167 (copym->m_flags & M_EXT || copym->m_len < sizeof(struct ip))) 2168 copym = m_pullup(copym, sizeof(struct ip)); 2169 if (copym == NULL) 2170 return; 2171 /* 2172 * We don't bother to fragment if the IP length is greater 2173 * than the interface's MTU. Can this possibly matter? 2174 */ 2175 ip = mtod(copym, struct ip *); 2176 2177 if (copym->m_pkthdr.csum_flags & (M_CSUM_TCPv4|M_CSUM_UDPv4)) { 2178 in_undefer_cksum_tcpudp(copym); 2179 copym->m_pkthdr.csum_flags &= 2180 ~(M_CSUM_TCPv4|M_CSUM_UDPv4); 2181 } 2182 2183 ip->ip_sum = 0; 2184 ip->ip_sum = in_cksum(copym, ip->ip_hl << 2); 2185 KERNEL_LOCK_UNLESS_NET_MPSAFE(); 2186 (void)looutput(ifp, copym, sintocsa(dst), NULL); 2187 KERNEL_UNLOCK_UNLESS_NET_MPSAFE(); 2188 } 2189 2190 /* 2191 * Ensure sending address is valid. 2192 * Returns 0 on success, -1 if an error should be sent back or 1 2193 * if the packet could be dropped without error (protocol dependent). 2194 */ 2195 static int 2196 ip_ifaddrvalid(const struct in_ifaddr *ia) 2197 { 2198 2199 if (ia->ia_addr.sin_addr.s_addr == INADDR_ANY) 2200 return 0; 2201 2202 if (ia->ia4_flags & IN_IFF_DUPLICATED) 2203 return -1; 2204 else if (ia->ia4_flags & (IN_IFF_TENTATIVE | IN_IFF_DETACHED)) 2205 return 1; 2206 2207 return 0; 2208 } 2209