ip_output.c revision 1.298.2.6
1 /* $NetBSD: ip_output.c,v 1.298.2.6 2018/07/28 04:38:10 pgoyette 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 1.298.2.6 2018/07/28 04:38:10 pgoyette 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 m_freem(m); 206 return error; 207 } 208 } 209 210 error = ip_mark_mpls(ifp, m, rt); 211 if (error != 0) { 212 m_freem(m); 213 return error; 214 } 215 216 error = if_output_lock(ifp, ifp, m, dst, rt); 217 218 return error; 219 } 220 221 /* 222 * IP output. The packet in mbuf chain m contains a skeletal IP 223 * header (with len, off, ttl, proto, tos, src, dst). 224 * The mbuf chain containing the packet will be freed. 225 * The mbuf opt, if present, will not be freed. 226 */ 227 int 228 ip_output(struct mbuf *m0, struct mbuf *opt, struct route *ro, int flags, 229 struct ip_moptions *imo, struct inpcb *inp) 230 { 231 struct rtentry *rt; 232 struct ip *ip; 233 struct ifnet *ifp, *mifp = NULL; 234 struct mbuf *m = m0; 235 int len, hlen, error = 0; 236 struct route iproute; 237 const struct sockaddr_in *dst; 238 struct in_ifaddr *ia = NULL; 239 struct ifaddr *ifa; 240 int isbroadcast; 241 int sw_csum; 242 u_long mtu; 243 bool natt_frag = false; 244 bool rtmtu_nolock; 245 union { 246 struct sockaddr sa; 247 struct sockaddr_in sin; 248 } udst, usrc; 249 struct sockaddr *rdst = &udst.sa; /* real IP destination, as 250 * opposed to the nexthop 251 */ 252 struct psref psref, psref_ia; 253 int bound; 254 bool bind_need_restore = false; 255 256 len = 0; 257 258 MCLAIM(m, &ip_tx_mowner); 259 260 KASSERT((m->m_flags & M_PKTHDR) != 0); 261 KASSERT((m->m_pkthdr.csum_flags & (M_CSUM_TCPv6|M_CSUM_UDPv6)) == 0); 262 KASSERT((m->m_pkthdr.csum_flags & (M_CSUM_TCPv4|M_CSUM_UDPv4)) != 263 (M_CSUM_TCPv4|M_CSUM_UDPv4)); 264 KASSERT(m->m_len >= sizeof(struct ip)); 265 266 hlen = sizeof(struct ip); 267 if (opt) { 268 m = ip_insertoptions(m, opt, &len); 269 hlen = len; 270 } 271 ip = mtod(m, struct ip *); 272 273 /* 274 * Fill in IP header. 275 */ 276 if ((flags & (IP_FORWARDING|IP_RAWOUTPUT)) == 0) { 277 ip->ip_v = IPVERSION; 278 ip->ip_off = htons(0); 279 /* ip->ip_id filled in after we find out source ia */ 280 ip->ip_hl = hlen >> 2; 281 IP_STATINC(IP_STAT_LOCALOUT); 282 } else { 283 hlen = ip->ip_hl << 2; 284 } 285 286 /* 287 * Route packet. 288 */ 289 if (ro == NULL) { 290 memset(&iproute, 0, sizeof(iproute)); 291 ro = &iproute; 292 } 293 sockaddr_in_init(&udst.sin, &ip->ip_dst, 0); 294 dst = satocsin(rtcache_getdst(ro)); 295 296 /* 297 * If there is a cached route, check that it is to the same 298 * destination and is still up. If not, free it and try again. 299 * The address family should also be checked in case of sharing 300 * the cache with IPv6. 301 */ 302 if (dst && (dst->sin_family != AF_INET || 303 !in_hosteq(dst->sin_addr, ip->ip_dst))) 304 rtcache_free(ro); 305 306 /* XXX must be before rtcache operations */ 307 bound = curlwp_bind(); 308 bind_need_restore = true; 309 310 if ((rt = rtcache_validate(ro)) == NULL && 311 (rt = rtcache_update(ro, 1)) == NULL) { 312 dst = &udst.sin; 313 error = rtcache_setdst(ro, &udst.sa); 314 if (error != 0) 315 goto bad; 316 } 317 318 /* 319 * If routing to interface only, short circuit routing lookup. 320 */ 321 if (flags & IP_ROUTETOIF) { 322 ifa = ifa_ifwithladdr_psref(sintocsa(dst), &psref_ia); 323 if (ifa == NULL) { 324 IP_STATINC(IP_STAT_NOROUTE); 325 error = ENETUNREACH; 326 goto bad; 327 } 328 /* ia is already referenced by psref_ia */ 329 ia = ifatoia(ifa); 330 331 ifp = ia->ia_ifp; 332 mtu = ifp->if_mtu; 333 ip->ip_ttl = 1; 334 isbroadcast = in_broadcast(dst->sin_addr, ifp); 335 } else if (((IN_MULTICAST(ip->ip_dst.s_addr) || 336 ip->ip_dst.s_addr == INADDR_BROADCAST) || 337 (flags & IP_ROUTETOIFINDEX)) && 338 imo != NULL && imo->imo_multicast_if_index != 0) { 339 ifp = mifp = if_get_byindex(imo->imo_multicast_if_index, &psref); 340 if (ifp == NULL) { 341 IP_STATINC(IP_STAT_NOROUTE); 342 error = ENETUNREACH; 343 goto bad; 344 } 345 mtu = ifp->if_mtu; 346 ia = in_get_ia_from_ifp_psref(ifp, &psref_ia); 347 if (ia == NULL) { 348 error = EADDRNOTAVAIL; 349 goto bad; 350 } 351 if (IN_MULTICAST(ip->ip_dst.s_addr) || 352 ip->ip_dst.s_addr == INADDR_BROADCAST) { 353 isbroadcast = 0; 354 } else { 355 /* IP_ROUTETOIFINDEX */ 356 isbroadcast = in_broadcast(dst->sin_addr, ifp); 357 if ((isbroadcast == 0) && ((ifp->if_flags & 358 (IFF_LOOPBACK | IFF_POINTOPOINT)) == 0) && 359 (in_direct(dst->sin_addr, ifp) == 0)) { 360 /* gateway address required */ 361 if (rt == NULL) 362 rt = rtcache_init(ro); 363 if (rt == NULL || rt->rt_ifp != ifp) { 364 IP_STATINC(IP_STAT_NOROUTE); 365 error = EHOSTUNREACH; 366 goto bad; 367 } 368 rt->rt_use++; 369 if (rt->rt_flags & RTF_GATEWAY) 370 dst = satosin(rt->rt_gateway); 371 if (rt->rt_flags & RTF_HOST) 372 isbroadcast = 373 rt->rt_flags & RTF_BROADCAST; 374 } 375 } 376 } else { 377 if (rt == NULL) 378 rt = rtcache_init(ro); 379 if (rt == NULL) { 380 IP_STATINC(IP_STAT_NOROUTE); 381 error = EHOSTUNREACH; 382 goto bad; 383 } 384 if (ifa_is_destroying(rt->rt_ifa)) { 385 rtcache_unref(rt, ro); 386 rt = NULL; 387 IP_STATINC(IP_STAT_NOROUTE); 388 error = EHOSTUNREACH; 389 goto bad; 390 } 391 ifa_acquire(rt->rt_ifa, &psref_ia); 392 ia = ifatoia(rt->rt_ifa); 393 ifp = rt->rt_ifp; 394 if ((mtu = rt->rt_rmx.rmx_mtu) == 0) 395 mtu = ifp->if_mtu; 396 rt->rt_use++; 397 if (rt->rt_flags & RTF_GATEWAY) 398 dst = satosin(rt->rt_gateway); 399 if (rt->rt_flags & RTF_HOST) 400 isbroadcast = rt->rt_flags & RTF_BROADCAST; 401 else 402 isbroadcast = in_broadcast(dst->sin_addr, ifp); 403 } 404 rtmtu_nolock = rt && (rt->rt_rmx.rmx_locks & RTV_MTU) == 0; 405 406 if (IN_MULTICAST(ip->ip_dst.s_addr) || 407 (ip->ip_dst.s_addr == INADDR_BROADCAST)) { 408 bool inmgroup; 409 410 m->m_flags |= (ip->ip_dst.s_addr == INADDR_BROADCAST) ? 411 M_BCAST : M_MCAST; 412 /* 413 * See if the caller provided any multicast options 414 */ 415 if (imo != NULL) 416 ip->ip_ttl = imo->imo_multicast_ttl; 417 else 418 ip->ip_ttl = IP_DEFAULT_MULTICAST_TTL; 419 420 /* 421 * if we don't know the outgoing ifp yet, we can't generate 422 * output 423 */ 424 if (!ifp) { 425 IP_STATINC(IP_STAT_NOROUTE); 426 error = ENETUNREACH; 427 goto bad; 428 } 429 430 /* 431 * If the packet is multicast or broadcast, confirm that 432 * the outgoing interface can transmit it. 433 */ 434 if (((m->m_flags & M_MCAST) && 435 (ifp->if_flags & IFF_MULTICAST) == 0) || 436 ((m->m_flags & M_BCAST) && 437 (ifp->if_flags & (IFF_BROADCAST|IFF_POINTOPOINT)) == 0)) { 438 IP_STATINC(IP_STAT_NOROUTE); 439 error = ENETUNREACH; 440 goto bad; 441 } 442 /* 443 * If source address not specified yet, use an address 444 * of outgoing interface. 445 */ 446 if (in_nullhost(ip->ip_src)) { 447 struct in_ifaddr *xia; 448 struct ifaddr *xifa; 449 struct psref _psref; 450 451 xia = in_get_ia_from_ifp_psref(ifp, &_psref); 452 if (!xia) { 453 error = EADDRNOTAVAIL; 454 goto bad; 455 } 456 xifa = &xia->ia_ifa; 457 if (xifa->ifa_getifa != NULL) { 458 ia4_release(xia, &_psref); 459 /* FIXME ifa_getifa is NOMPSAFE */ 460 xia = ifatoia((*xifa->ifa_getifa)(xifa, rdst)); 461 if (xia == NULL) { 462 error = EADDRNOTAVAIL; 463 goto bad; 464 } 465 ia4_acquire(xia, &_psref); 466 } 467 ip->ip_src = xia->ia_addr.sin_addr; 468 ia4_release(xia, &_psref); 469 } 470 471 inmgroup = in_multi_group(ip->ip_dst, ifp, flags); 472 if (inmgroup && (imo == NULL || imo->imo_multicast_loop)) { 473 /* 474 * If we belong to the destination multicast group 475 * on the outgoing interface, and the caller did not 476 * forbid loopback, loop back a copy. 477 */ 478 ip_mloopback(ifp, m, &udst.sin); 479 } 480 #ifdef MROUTING 481 else { 482 /* 483 * If we are acting as a multicast router, perform 484 * multicast forwarding as if the packet had just 485 * arrived on the interface to which we are about 486 * to send. The multicast forwarding function 487 * recursively calls this function, using the 488 * IP_FORWARDING flag to prevent infinite recursion. 489 * 490 * Multicasts that are looped back by ip_mloopback(), 491 * above, will be forwarded by the ip_input() routine, 492 * if necessary. 493 */ 494 extern struct socket *ip_mrouter; 495 496 if (ip_mrouter && (flags & IP_FORWARDING) == 0) { 497 if (ip_mforward(m, ifp) != 0) { 498 m_freem(m); 499 goto done; 500 } 501 } 502 } 503 #endif 504 /* 505 * Multicasts with a time-to-live of zero may be looped- 506 * back, above, but must not be transmitted on a network. 507 * Also, multicasts addressed to the loopback interface 508 * are not sent -- the above call to ip_mloopback() will 509 * loop back a copy if this host actually belongs to the 510 * destination group on the loopback interface. 511 */ 512 if (ip->ip_ttl == 0 || (ifp->if_flags & IFF_LOOPBACK) != 0) { 513 m_freem(m); 514 goto done; 515 } 516 goto sendit; 517 } 518 519 /* 520 * If source address not specified yet, use address 521 * of outgoing interface. 522 */ 523 if (in_nullhost(ip->ip_src)) { 524 struct ifaddr *xifa; 525 526 xifa = &ia->ia_ifa; 527 if (xifa->ifa_getifa != NULL) { 528 ia4_release(ia, &psref_ia); 529 /* FIXME ifa_getifa is NOMPSAFE */ 530 ia = ifatoia((*xifa->ifa_getifa)(xifa, rdst)); 531 if (ia == NULL) { 532 error = EADDRNOTAVAIL; 533 goto bad; 534 } 535 ia4_acquire(ia, &psref_ia); 536 } 537 ip->ip_src = ia->ia_addr.sin_addr; 538 } 539 540 /* 541 * Packets with Class-D address as source are not valid per 542 * RFC1112. 543 */ 544 if (IN_MULTICAST(ip->ip_src.s_addr)) { 545 IP_STATINC(IP_STAT_ODROPPED); 546 error = EADDRNOTAVAIL; 547 goto bad; 548 } 549 550 /* 551 * Look for broadcast address and verify user is allowed to 552 * send such a packet. 553 */ 554 if (isbroadcast) { 555 if ((ifp->if_flags & IFF_BROADCAST) == 0) { 556 error = EADDRNOTAVAIL; 557 goto bad; 558 } 559 if ((flags & IP_ALLOWBROADCAST) == 0) { 560 error = EACCES; 561 goto bad; 562 } 563 /* don't allow broadcast messages to be fragmented */ 564 if (ntohs(ip->ip_len) > ifp->if_mtu) { 565 error = EMSGSIZE; 566 goto bad; 567 } 568 m->m_flags |= M_BCAST; 569 } else 570 m->m_flags &= ~M_BCAST; 571 572 sendit: 573 if ((flags & (IP_FORWARDING|IP_NOIPNEWID)) == 0) { 574 if (m->m_pkthdr.len < IP_MINFRAGSIZE) { 575 ip->ip_id = 0; 576 } else if ((m->m_pkthdr.csum_flags & M_CSUM_TSOv4) == 0) { 577 ip->ip_id = ip_newid(ia); 578 } else { 579 /* 580 * TSO capable interfaces (typically?) increment 581 * ip_id for each segment. 582 * "allocate" enough ids here to increase the chance 583 * for them to be unique. 584 * 585 * note that the following calculation is not 586 * needed to be precise. wasting some ip_id is fine. 587 */ 588 589 unsigned int segsz = m->m_pkthdr.segsz; 590 unsigned int datasz = ntohs(ip->ip_len) - hlen; 591 unsigned int num = howmany(datasz, segsz); 592 593 ip->ip_id = ip_newid_range(ia, num); 594 } 595 } 596 if (ia != NULL) { 597 ia4_release(ia, &psref_ia); 598 ia = NULL; 599 } 600 601 /* 602 * If we're doing Path MTU Discovery, we need to set DF unless 603 * the route's MTU is locked. 604 */ 605 if ((flags & IP_MTUDISC) != 0 && rtmtu_nolock) { 606 ip->ip_off |= htons(IP_DF); 607 } 608 609 #ifdef IPSEC 610 if (ipsec_used) { 611 bool ipsec_done = false; 612 613 /* Perform IPsec processing, if any. */ 614 error = ipsec4_output(m, inp, flags, &mtu, &natt_frag, 615 &ipsec_done); 616 if (error || ipsec_done) 617 goto done; 618 } 619 #endif 620 621 /* 622 * Run through list of hooks for output packets. 623 */ 624 error = pfil_run_hooks(inet_pfil_hook, &m, ifp, PFIL_OUT); 625 if (error) 626 goto done; 627 if (m == NULL) 628 goto done; 629 630 ip = mtod(m, struct ip *); 631 hlen = ip->ip_hl << 2; 632 633 m->m_pkthdr.csum_data |= hlen << 16; 634 635 /* 636 * search for the source address structure to 637 * maintain output statistics, and verify address 638 * validity 639 */ 640 KASSERT(ia == NULL); 641 sockaddr_in_init(&usrc.sin, &ip->ip_src, 0); 642 ifa = ifaof_ifpforaddr_psref(&usrc.sa, ifp, &psref_ia); 643 if (ifa != NULL) 644 ia = ifatoia(ifa); 645 646 /* 647 * Ensure we only send from a valid address. 648 * A NULL address is valid because the packet could be 649 * generated from a packet filter. 650 */ 651 if (ia != NULL && (flags & IP_FORWARDING) == 0 && 652 (error = ip_ifaddrvalid(ia)) != 0) 653 { 654 ARPLOG(LOG_ERR, 655 "refusing to send from invalid address %s (pid %d)\n", 656 ARPLOGADDR(&ip->ip_src), curproc->p_pid); 657 IP_STATINC(IP_STAT_ODROPPED); 658 if (error == 1) 659 /* 660 * Address exists, but is tentative or detached. 661 * We can't send from it because it's invalid, 662 * so we drop the packet. 663 */ 664 error = 0; 665 else 666 error = EADDRNOTAVAIL; 667 goto bad; 668 } 669 670 /* Maybe skip checksums on loopback interfaces. */ 671 if (IN_NEED_CHECKSUM(ifp, M_CSUM_IPv4)) { 672 m->m_pkthdr.csum_flags |= M_CSUM_IPv4; 673 } 674 sw_csum = m->m_pkthdr.csum_flags & ~ifp->if_csum_flags_tx; 675 676 /* 677 * If small enough for mtu of path, or if using TCP segmentation 678 * offload, can just send directly. 679 */ 680 if (ntohs(ip->ip_len) <= mtu || 681 (m->m_pkthdr.csum_flags & M_CSUM_TSOv4) != 0) { 682 const struct sockaddr *sa; 683 684 #if IFA_STATS 685 if (ia) 686 ia->ia_ifa.ifa_data.ifad_outbytes += ntohs(ip->ip_len); 687 #endif 688 /* 689 * Always initialize the sum to 0! Some HW assisted 690 * checksumming requires this. 691 */ 692 ip->ip_sum = 0; 693 694 if ((m->m_pkthdr.csum_flags & M_CSUM_TSOv4) == 0) { 695 /* 696 * Perform any checksums that the hardware can't do 697 * for us. 698 * 699 * XXX Does any hardware require the {th,uh}_sum 700 * XXX fields to be 0? 701 */ 702 if (sw_csum & M_CSUM_IPv4) { 703 KASSERT(IN_NEED_CHECKSUM(ifp, M_CSUM_IPv4)); 704 ip->ip_sum = in_cksum(m, hlen); 705 m->m_pkthdr.csum_flags &= ~M_CSUM_IPv4; 706 } 707 if (sw_csum & (M_CSUM_TCPv4|M_CSUM_UDPv4)) { 708 if (IN_NEED_CHECKSUM(ifp, 709 sw_csum & (M_CSUM_TCPv4|M_CSUM_UDPv4))) { 710 in_undefer_cksum_tcpudp(m); 711 } 712 m->m_pkthdr.csum_flags &= 713 ~(M_CSUM_TCPv4|M_CSUM_UDPv4); 714 } 715 } 716 717 sa = (m->m_flags & M_MCAST) ? sintocsa(rdst) : sintocsa(dst); 718 if (__predict_true( 719 (m->m_pkthdr.csum_flags & M_CSUM_TSOv4) == 0 || 720 (ifp->if_capenable & IFCAP_TSOv4) != 0)) { 721 error = ip_if_output(ifp, m, sa, rt); 722 } else { 723 error = ip_tso_output(ifp, m, sa, rt); 724 } 725 goto done; 726 } 727 728 /* 729 * We can't use HW checksumming if we're about to fragment the packet. 730 * 731 * XXX Some hardware can do this. 732 */ 733 if (m->m_pkthdr.csum_flags & (M_CSUM_TCPv4|M_CSUM_UDPv4)) { 734 if (IN_NEED_CHECKSUM(ifp, 735 m->m_pkthdr.csum_flags & (M_CSUM_TCPv4|M_CSUM_UDPv4))) { 736 in_undefer_cksum_tcpudp(m); 737 } 738 m->m_pkthdr.csum_flags &= ~(M_CSUM_TCPv4|M_CSUM_UDPv4); 739 } 740 741 /* 742 * Too large for interface; fragment if possible. 743 * Must be able to put at least 8 bytes per fragment. 744 */ 745 if (ntohs(ip->ip_off) & IP_DF) { 746 if (flags & IP_RETURNMTU) { 747 KASSERT(inp != NULL); 748 inp->inp_errormtu = mtu; 749 } 750 error = EMSGSIZE; 751 IP_STATINC(IP_STAT_CANTFRAG); 752 goto bad; 753 } 754 755 error = ip_fragment(m, ifp, mtu); 756 if (error) { 757 m = NULL; 758 goto bad; 759 } 760 761 for (; m; m = m0) { 762 m0 = m->m_nextpkt; 763 m->m_nextpkt = NULL; 764 if (error) { 765 m_freem(m); 766 continue; 767 } 768 #if IFA_STATS 769 if (ia) 770 ia->ia_ifa.ifa_data.ifad_outbytes += ntohs(ip->ip_len); 771 #endif 772 /* 773 * If we get there, the packet has not been handled by 774 * IPsec whereas it should have. Now that it has been 775 * fragmented, re-inject it in ip_output so that IPsec 776 * processing can occur. 777 */ 778 if (natt_frag) { 779 error = ip_output(m, opt, ro, 780 flags | IP_RAWOUTPUT | IP_NOIPNEWID, 781 imo, inp); 782 } else { 783 KASSERT((m->m_pkthdr.csum_flags & 784 (M_CSUM_UDPv4 | M_CSUM_TCPv4)) == 0); 785 error = ip_if_output(ifp, m, 786 (m->m_flags & M_MCAST) ? 787 sintocsa(rdst) : sintocsa(dst), rt); 788 } 789 } 790 if (error == 0) { 791 IP_STATINC(IP_STAT_FRAGMENTED); 792 } 793 794 done: 795 ia4_release(ia, &psref_ia); 796 rtcache_unref(rt, ro); 797 if (ro == &iproute) { 798 rtcache_free(&iproute); 799 } 800 if (mifp != NULL) { 801 if_put(mifp, &psref); 802 } 803 if (bind_need_restore) 804 curlwp_bindx(bound); 805 return error; 806 807 bad: 808 m_freem(m); 809 goto done; 810 } 811 812 int 813 ip_fragment(struct mbuf *m, struct ifnet *ifp, u_long mtu) 814 { 815 struct ip *ip, *mhip; 816 struct mbuf *m0; 817 int len, hlen, off; 818 int mhlen, firstlen; 819 struct mbuf **mnext; 820 int sw_csum = m->m_pkthdr.csum_flags; 821 int fragments = 0; 822 int error = 0; 823 int ipoff, ipflg; 824 825 ip = mtod(m, struct ip *); 826 hlen = ip->ip_hl << 2; 827 828 /* Preserve the offset and flags. */ 829 ipoff = ntohs(ip->ip_off) & IP_OFFMASK; 830 ipflg = ntohs(ip->ip_off) & (IP_RF|IP_DF|IP_MF); 831 832 if (ifp != NULL) 833 sw_csum &= ~ifp->if_csum_flags_tx; 834 835 len = (mtu - hlen) &~ 7; 836 if (len < 8) { 837 m_freem(m); 838 return EMSGSIZE; 839 } 840 841 firstlen = len; 842 mnext = &m->m_nextpkt; 843 844 /* 845 * Loop through length of segment after first fragment, 846 * make new header and copy data of each part and link onto chain. 847 */ 848 m0 = m; 849 mhlen = sizeof(struct ip); 850 for (off = hlen + len; off < ntohs(ip->ip_len); off += len) { 851 MGETHDR(m, M_DONTWAIT, MT_HEADER); 852 if (m == NULL) { 853 error = ENOBUFS; 854 IP_STATINC(IP_STAT_ODROPPED); 855 goto sendorfree; 856 } 857 MCLAIM(m, m0->m_owner); 858 859 *mnext = m; 860 mnext = &m->m_nextpkt; 861 862 m->m_data += max_linkhdr; 863 mhip = mtod(m, struct ip *); 864 *mhip = *ip; 865 866 /* we must inherit the flags */ 867 m->m_flags |= m0->m_flags & M_COPYFLAGS; 868 869 if (hlen > sizeof(struct ip)) { 870 mhlen = ip_optcopy(ip, mhip) + sizeof(struct ip); 871 mhip->ip_hl = mhlen >> 2; 872 } 873 m->m_len = mhlen; 874 875 mhip->ip_off = ((off - hlen) >> 3) + ipoff; 876 mhip->ip_off |= ipflg; 877 if (off + len >= ntohs(ip->ip_len)) 878 len = ntohs(ip->ip_len) - off; 879 else 880 mhip->ip_off |= IP_MF; 881 HTONS(mhip->ip_off); 882 883 mhip->ip_len = htons((u_int16_t)(len + mhlen)); 884 m->m_next = m_copym(m0, off, len, M_DONTWAIT); 885 if (m->m_next == NULL) { 886 error = ENOBUFS; 887 IP_STATINC(IP_STAT_ODROPPED); 888 goto sendorfree; 889 } 890 891 m->m_pkthdr.len = mhlen + len; 892 m_reset_rcvif(m); 893 894 mhip->ip_sum = 0; 895 KASSERT((m->m_pkthdr.csum_flags & M_CSUM_IPv4) == 0); 896 if (sw_csum & M_CSUM_IPv4) { 897 mhip->ip_sum = in_cksum(m, mhlen); 898 } else { 899 /* 900 * checksum is hw-offloaded or not necessary. 901 */ 902 m->m_pkthdr.csum_flags |= 903 m0->m_pkthdr.csum_flags & M_CSUM_IPv4; 904 m->m_pkthdr.csum_data |= mhlen << 16; 905 KASSERT(!(ifp != NULL && 906 IN_NEED_CHECKSUM(ifp, M_CSUM_IPv4)) || 907 (m->m_pkthdr.csum_flags & M_CSUM_IPv4) != 0); 908 } 909 IP_STATINC(IP_STAT_OFRAGMENTS); 910 fragments++; 911 } 912 913 /* 914 * Update first fragment by trimming what's been copied out 915 * and updating header, then send each fragment (in order). 916 */ 917 m = m0; 918 m_adj(m, hlen + firstlen - ntohs(ip->ip_len)); 919 m->m_pkthdr.len = hlen + firstlen; 920 ip->ip_len = htons((u_int16_t)m->m_pkthdr.len); 921 ip->ip_off |= htons(IP_MF); 922 ip->ip_sum = 0; 923 if (sw_csum & M_CSUM_IPv4) { 924 ip->ip_sum = in_cksum(m, hlen); 925 m->m_pkthdr.csum_flags &= ~M_CSUM_IPv4; 926 } else { 927 /* 928 * checksum is hw-offloaded or not necessary. 929 */ 930 KASSERT(!(ifp != NULL && IN_NEED_CHECKSUM(ifp, M_CSUM_IPv4)) || 931 (m->m_pkthdr.csum_flags & M_CSUM_IPv4) != 0); 932 KASSERT(M_CSUM_DATA_IPv4_IPHL(m->m_pkthdr.csum_data) >= 933 sizeof(struct ip)); 934 } 935 936 sendorfree: 937 /* 938 * If there is no room for all the fragments, don't queue 939 * any of them. 940 */ 941 if (ifp != NULL) { 942 IFQ_LOCK(&ifp->if_snd); 943 if (ifp->if_snd.ifq_maxlen - ifp->if_snd.ifq_len < fragments && 944 error == 0) { 945 error = ENOBUFS; 946 IP_STATINC(IP_STAT_ODROPPED); 947 IFQ_INC_DROPS(&ifp->if_snd); 948 } 949 IFQ_UNLOCK(&ifp->if_snd); 950 } 951 if (error) { 952 for (m = m0; m; m = m0) { 953 m0 = m->m_nextpkt; 954 m->m_nextpkt = NULL; 955 m_freem(m); 956 } 957 } 958 959 return error; 960 } 961 962 /* 963 * Determine the maximum length of the options to be inserted; 964 * we would far rather allocate too much space rather than too little. 965 */ 966 u_int 967 ip_optlen(struct inpcb *inp) 968 { 969 struct mbuf *m = inp->inp_options; 970 971 if (m && m->m_len > offsetof(struct ipoption, ipopt_dst)) { 972 return (m->m_len - offsetof(struct ipoption, ipopt_dst)); 973 } 974 return 0; 975 } 976 977 /* 978 * Insert IP options into preformed packet. 979 * Adjust IP destination as required for IP source routing, 980 * as indicated by a non-zero in_addr at the start of the options. 981 */ 982 static struct mbuf * 983 ip_insertoptions(struct mbuf *m, struct mbuf *opt, int *phlen) 984 { 985 struct ipoption *p = mtod(opt, struct ipoption *); 986 struct mbuf *n; 987 struct ip *ip = mtod(m, struct ip *); 988 unsigned optlen; 989 990 optlen = opt->m_len - sizeof(p->ipopt_dst); 991 KASSERT(optlen % 4 == 0); 992 if (optlen + ntohs(ip->ip_len) > IP_MAXPACKET) 993 return m; /* XXX should fail */ 994 if (!in_nullhost(p->ipopt_dst)) 995 ip->ip_dst = p->ipopt_dst; 996 if (M_READONLY(m) || M_LEADINGSPACE(m) < optlen) { 997 MGETHDR(n, M_DONTWAIT, MT_HEADER); 998 if (n == NULL) 999 return m; 1000 MCLAIM(n, m->m_owner); 1001 M_MOVE_PKTHDR(n, m); 1002 m->m_len -= sizeof(struct ip); 1003 m->m_data += sizeof(struct ip); 1004 n->m_next = m; 1005 n->m_len = optlen + sizeof(struct ip); 1006 n->m_data += max_linkhdr; 1007 memcpy(mtod(n, void *), ip, sizeof(struct ip)); 1008 m = n; 1009 } else { 1010 m->m_data -= optlen; 1011 m->m_len += optlen; 1012 memmove(mtod(m, void *), ip, sizeof(struct ip)); 1013 } 1014 m->m_pkthdr.len += optlen; 1015 ip = mtod(m, struct ip *); 1016 memcpy(ip + 1, p->ipopt_list, optlen); 1017 *phlen = sizeof(struct ip) + optlen; 1018 ip->ip_len = htons(ntohs(ip->ip_len) + optlen); 1019 return m; 1020 } 1021 1022 /* 1023 * Copy options from ipsrc to ipdst, omitting those not copied during 1024 * fragmentation. 1025 */ 1026 int 1027 ip_optcopy(struct ip *ipsrc, struct ip *ipdst) 1028 { 1029 u_char *cp, *dp; 1030 int opt, optlen, cnt; 1031 1032 cp = (u_char *)(ipsrc + 1); 1033 dp = (u_char *)(ipdst + 1); 1034 cnt = (ipsrc->ip_hl << 2) - sizeof(struct ip); 1035 for (; cnt > 0; cnt -= optlen, cp += optlen) { 1036 opt = cp[0]; 1037 if (opt == IPOPT_EOL) 1038 break; 1039 if (opt == IPOPT_NOP) { 1040 /* Preserve for IP mcast tunnel's LSRR alignment. */ 1041 *dp++ = IPOPT_NOP; 1042 optlen = 1; 1043 continue; 1044 } 1045 1046 KASSERT(cnt >= IPOPT_OLEN + sizeof(*cp)); 1047 optlen = cp[IPOPT_OLEN]; 1048 KASSERT(optlen >= IPOPT_OLEN + sizeof(*cp) && optlen < cnt); 1049 1050 /* Invalid lengths should have been caught by ip_dooptions. */ 1051 if (optlen > cnt) 1052 optlen = cnt; 1053 if (IPOPT_COPIED(opt)) { 1054 bcopy((void *)cp, (void *)dp, (unsigned)optlen); 1055 dp += optlen; 1056 } 1057 } 1058 1059 for (optlen = dp - (u_char *)(ipdst+1); optlen & 0x3; optlen++) { 1060 *dp++ = IPOPT_EOL; 1061 } 1062 1063 return optlen; 1064 } 1065 1066 /* 1067 * IP socket option processing. 1068 */ 1069 int 1070 ip_ctloutput(int op, struct socket *so, struct sockopt *sopt) 1071 { 1072 struct inpcb *inp = sotoinpcb(so); 1073 struct ip *ip = &inp->inp_ip; 1074 int inpflags = inp->inp_flags; 1075 int optval = 0, error = 0; 1076 struct in_pktinfo pktinfo; 1077 1078 KASSERT(solocked(so)); 1079 1080 if (sopt->sopt_level != IPPROTO_IP) { 1081 if (sopt->sopt_level == SOL_SOCKET && sopt->sopt_name == SO_NOHEADER) 1082 return 0; 1083 return ENOPROTOOPT; 1084 } 1085 1086 switch (op) { 1087 case PRCO_SETOPT: 1088 switch (sopt->sopt_name) { 1089 case IP_OPTIONS: 1090 #ifdef notyet 1091 case IP_RETOPTS: 1092 #endif 1093 error = ip_pcbopts(inp, sopt); 1094 break; 1095 1096 case IP_TOS: 1097 case IP_TTL: 1098 case IP_MINTTL: 1099 case IP_RECVOPTS: 1100 case IP_RECVRETOPTS: 1101 case IP_RECVDSTADDR: 1102 case IP_RECVIF: 1103 case IP_RECVPKTINFO: 1104 case IP_RECVTTL: 1105 error = sockopt_getint(sopt, &optval); 1106 if (error) 1107 break; 1108 1109 switch (sopt->sopt_name) { 1110 case IP_TOS: 1111 ip->ip_tos = optval; 1112 break; 1113 1114 case IP_TTL: 1115 ip->ip_ttl = optval; 1116 break; 1117 1118 case IP_MINTTL: 1119 if (optval > 0 && optval <= MAXTTL) 1120 inp->inp_ip_minttl = optval; 1121 else 1122 error = EINVAL; 1123 break; 1124 #define OPTSET(bit) \ 1125 if (optval) \ 1126 inpflags |= bit; \ 1127 else \ 1128 inpflags &= ~bit; 1129 1130 case IP_RECVOPTS: 1131 OPTSET(INP_RECVOPTS); 1132 break; 1133 1134 case IP_RECVPKTINFO: 1135 OPTSET(INP_RECVPKTINFO); 1136 break; 1137 1138 case IP_RECVRETOPTS: 1139 OPTSET(INP_RECVRETOPTS); 1140 break; 1141 1142 case IP_RECVDSTADDR: 1143 OPTSET(INP_RECVDSTADDR); 1144 break; 1145 1146 case IP_RECVIF: 1147 OPTSET(INP_RECVIF); 1148 break; 1149 1150 case IP_RECVTTL: 1151 OPTSET(INP_RECVTTL); 1152 break; 1153 } 1154 break; 1155 case IP_PKTINFO: 1156 error = sockopt_getint(sopt, &optval); 1157 if (!error) { 1158 /* Linux compatibility */ 1159 OPTSET(INP_RECVPKTINFO); 1160 break; 1161 } 1162 error = sockopt_get(sopt, &pktinfo, sizeof(pktinfo)); 1163 if (error) 1164 break; 1165 1166 if (pktinfo.ipi_ifindex == 0) { 1167 inp->inp_prefsrcip = pktinfo.ipi_addr; 1168 break; 1169 } 1170 1171 /* Solaris compatibility */ 1172 struct ifnet *ifp; 1173 struct in_ifaddr *ia; 1174 int s; 1175 1176 /* pick up primary address */ 1177 s = pserialize_read_enter(); 1178 ifp = if_byindex(pktinfo.ipi_ifindex); 1179 if (ifp == NULL) { 1180 pserialize_read_exit(s); 1181 error = EADDRNOTAVAIL; 1182 break; 1183 } 1184 ia = in_get_ia_from_ifp(ifp); 1185 if (ia == NULL) { 1186 pserialize_read_exit(s); 1187 error = EADDRNOTAVAIL; 1188 break; 1189 } 1190 inp->inp_prefsrcip = IA_SIN(ia)->sin_addr; 1191 pserialize_read_exit(s); 1192 break; 1193 break; 1194 #undef OPTSET 1195 1196 case IP_MULTICAST_IF: 1197 case IP_MULTICAST_TTL: 1198 case IP_MULTICAST_LOOP: 1199 case IP_ADD_MEMBERSHIP: 1200 case IP_DROP_MEMBERSHIP: 1201 error = ip_setmoptions(&inp->inp_moptions, sopt); 1202 break; 1203 1204 case IP_PORTRANGE: 1205 error = sockopt_getint(sopt, &optval); 1206 if (error) 1207 break; 1208 1209 switch (optval) { 1210 case IP_PORTRANGE_DEFAULT: 1211 case IP_PORTRANGE_HIGH: 1212 inpflags &= ~(INP_LOWPORT); 1213 break; 1214 1215 case IP_PORTRANGE_LOW: 1216 inpflags |= INP_LOWPORT; 1217 break; 1218 1219 default: 1220 error = EINVAL; 1221 break; 1222 } 1223 break; 1224 1225 case IP_PORTALGO: 1226 error = sockopt_getint(sopt, &optval); 1227 if (error) 1228 break; 1229 1230 error = portalgo_algo_index_select( 1231 (struct inpcb_hdr *)inp, optval); 1232 break; 1233 1234 #if defined(IPSEC) 1235 case IP_IPSEC_POLICY: 1236 if (ipsec_enabled) { 1237 error = ipsec_set_policy(inp, 1238 sopt->sopt_data, sopt->sopt_size, 1239 curlwp->l_cred); 1240 break; 1241 } 1242 /*FALLTHROUGH*/ 1243 #endif /* IPSEC */ 1244 1245 default: 1246 error = ENOPROTOOPT; 1247 break; 1248 } 1249 break; 1250 1251 case PRCO_GETOPT: 1252 switch (sopt->sopt_name) { 1253 case IP_OPTIONS: 1254 case IP_RETOPTS: { 1255 struct mbuf *mopts = inp->inp_options; 1256 1257 if (mopts) { 1258 struct mbuf *m; 1259 1260 m = m_copym(mopts, 0, M_COPYALL, M_DONTWAIT); 1261 if (m == NULL) { 1262 error = ENOBUFS; 1263 break; 1264 } 1265 error = sockopt_setmbuf(sopt, m); 1266 } 1267 break; 1268 } 1269 case IP_TOS: 1270 case IP_TTL: 1271 case IP_MINTTL: 1272 case IP_RECVOPTS: 1273 case IP_RECVRETOPTS: 1274 case IP_RECVDSTADDR: 1275 case IP_RECVIF: 1276 case IP_RECVPKTINFO: 1277 case IP_RECVTTL: 1278 case IP_ERRORMTU: 1279 switch (sopt->sopt_name) { 1280 case IP_TOS: 1281 optval = ip->ip_tos; 1282 break; 1283 1284 case IP_TTL: 1285 optval = ip->ip_ttl; 1286 break; 1287 1288 case IP_MINTTL: 1289 optval = inp->inp_ip_minttl; 1290 break; 1291 1292 case IP_ERRORMTU: 1293 optval = inp->inp_errormtu; 1294 break; 1295 1296 #define OPTBIT(bit) (inpflags & bit ? 1 : 0) 1297 1298 case IP_RECVOPTS: 1299 optval = OPTBIT(INP_RECVOPTS); 1300 break; 1301 1302 case IP_RECVPKTINFO: 1303 optval = OPTBIT(INP_RECVPKTINFO); 1304 break; 1305 1306 case IP_RECVRETOPTS: 1307 optval = OPTBIT(INP_RECVRETOPTS); 1308 break; 1309 1310 case IP_RECVDSTADDR: 1311 optval = OPTBIT(INP_RECVDSTADDR); 1312 break; 1313 1314 case IP_RECVIF: 1315 optval = OPTBIT(INP_RECVIF); 1316 break; 1317 1318 case IP_RECVTTL: 1319 optval = OPTBIT(INP_RECVTTL); 1320 break; 1321 } 1322 error = sockopt_setint(sopt, optval); 1323 break; 1324 1325 case IP_PKTINFO: 1326 switch (sopt->sopt_size) { 1327 case sizeof(int): 1328 /* Linux compatibility */ 1329 optval = OPTBIT(INP_RECVPKTINFO); 1330 error = sockopt_setint(sopt, optval); 1331 break; 1332 case sizeof(struct in_pktinfo): 1333 /* Solaris compatibility */ 1334 pktinfo.ipi_ifindex = 0; 1335 pktinfo.ipi_addr = inp->inp_prefsrcip; 1336 error = sockopt_set(sopt, &pktinfo, 1337 sizeof(pktinfo)); 1338 break; 1339 default: 1340 /* 1341 * While size is stuck at 0, and, later, if 1342 * the caller doesn't use an exactly sized 1343 * recipient for the data, default to Linux 1344 * compatibility 1345 */ 1346 optval = OPTBIT(INP_RECVPKTINFO); 1347 error = sockopt_setint(sopt, optval); 1348 break; 1349 } 1350 break; 1351 1352 #if 0 /* defined(IPSEC) */ 1353 case IP_IPSEC_POLICY: 1354 { 1355 struct mbuf *m = NULL; 1356 1357 /* XXX this will return EINVAL as sopt is empty */ 1358 error = ipsec_get_policy(inp, sopt->sopt_data, 1359 sopt->sopt_size, &m); 1360 if (error == 0) 1361 error = sockopt_setmbuf(sopt, m); 1362 break; 1363 } 1364 #endif /*IPSEC*/ 1365 1366 case IP_MULTICAST_IF: 1367 case IP_MULTICAST_TTL: 1368 case IP_MULTICAST_LOOP: 1369 case IP_ADD_MEMBERSHIP: 1370 case IP_DROP_MEMBERSHIP: 1371 error = ip_getmoptions(inp->inp_moptions, sopt); 1372 break; 1373 1374 case IP_PORTRANGE: 1375 if (inpflags & INP_LOWPORT) 1376 optval = IP_PORTRANGE_LOW; 1377 else 1378 optval = IP_PORTRANGE_DEFAULT; 1379 error = sockopt_setint(sopt, optval); 1380 break; 1381 1382 case IP_PORTALGO: 1383 optval = inp->inp_portalgo; 1384 error = sockopt_setint(sopt, optval); 1385 break; 1386 1387 default: 1388 error = ENOPROTOOPT; 1389 break; 1390 } 1391 break; 1392 } 1393 1394 if (!error) { 1395 inp->inp_flags = inpflags; 1396 } 1397 return error; 1398 } 1399 1400 static int 1401 ip_pktinfo_prepare(const struct in_pktinfo *pktinfo, struct ip_pktopts *pktopts, 1402 int *flags, kauth_cred_t cred) 1403 { 1404 struct ip_moptions *imo; 1405 int error = 0; 1406 bool addrset = false; 1407 1408 if (!in_nullhost(pktinfo->ipi_addr)) { 1409 pktopts->ippo_laddr.sin_addr = pktinfo->ipi_addr; 1410 /* EADDRNOTAVAIL? */ 1411 error = in_pcbbindableaddr(&pktopts->ippo_laddr, cred); 1412 if (error != 0) 1413 return error; 1414 addrset = true; 1415 } 1416 1417 if (pktinfo->ipi_ifindex != 0) { 1418 if (!addrset) { 1419 struct ifnet *ifp; 1420 struct in_ifaddr *ia; 1421 int s; 1422 1423 /* pick up primary address */ 1424 s = pserialize_read_enter(); 1425 ifp = if_byindex(pktinfo->ipi_ifindex); 1426 if (ifp == NULL) { 1427 pserialize_read_exit(s); 1428 return EADDRNOTAVAIL; 1429 } 1430 ia = in_get_ia_from_ifp(ifp); 1431 if (ia == NULL) { 1432 pserialize_read_exit(s); 1433 return EADDRNOTAVAIL; 1434 } 1435 pktopts->ippo_laddr.sin_addr = IA_SIN(ia)->sin_addr; 1436 pserialize_read_exit(s); 1437 } 1438 1439 /* 1440 * If specified ipi_ifindex, 1441 * use copied or locally initialized ip_moptions. 1442 * Original ip_moptions must not be modified. 1443 */ 1444 imo = &pktopts->ippo_imobuf; /* local buf in pktopts */ 1445 if (pktopts->ippo_imo != NULL) { 1446 memcpy(imo, pktopts->ippo_imo, sizeof(*imo)); 1447 } else { 1448 memset(imo, 0, sizeof(*imo)); 1449 imo->imo_multicast_ttl = IP_DEFAULT_MULTICAST_TTL; 1450 imo->imo_multicast_loop = IP_DEFAULT_MULTICAST_LOOP; 1451 } 1452 imo->imo_multicast_if_index = pktinfo->ipi_ifindex; 1453 pktopts->ippo_imo = imo; 1454 *flags |= IP_ROUTETOIFINDEX; 1455 } 1456 return error; 1457 } 1458 1459 /* 1460 * Set up IP outgoing packet options. Even if control is NULL, 1461 * pktopts->ippo_laddr and pktopts->ippo_imo are set and used. 1462 */ 1463 int 1464 ip_setpktopts(struct mbuf *control, struct ip_pktopts *pktopts, int *flags, 1465 struct inpcb *inp, kauth_cred_t cred) 1466 { 1467 struct cmsghdr *cm; 1468 struct in_pktinfo pktinfo; 1469 int error; 1470 1471 pktopts->ippo_imo = inp->inp_moptions; 1472 1473 struct in_addr *ia = in_nullhost(inp->inp_prefsrcip) ? &inp->inp_laddr : 1474 &inp->inp_prefsrcip; 1475 sockaddr_in_init(&pktopts->ippo_laddr, ia, 0); 1476 1477 if (control == NULL) 1478 return 0; 1479 1480 /* 1481 * XXX: Currently, we assume all the optional information is 1482 * stored in a single mbuf. 1483 */ 1484 if (control->m_next) 1485 return EINVAL; 1486 1487 for (; control->m_len > 0; 1488 control->m_data += CMSG_ALIGN(cm->cmsg_len), 1489 control->m_len -= CMSG_ALIGN(cm->cmsg_len)) { 1490 cm = mtod(control, struct cmsghdr *); 1491 if ((control->m_len < sizeof(*cm)) || 1492 (cm->cmsg_len == 0) || 1493 (cm->cmsg_len > control->m_len)) { 1494 return EINVAL; 1495 } 1496 if (cm->cmsg_level != IPPROTO_IP) 1497 continue; 1498 1499 switch (cm->cmsg_type) { 1500 case IP_PKTINFO: 1501 if (cm->cmsg_len != CMSG_LEN(sizeof(pktinfo))) 1502 return EINVAL; 1503 memcpy(&pktinfo, CMSG_DATA(cm), sizeof(pktinfo)); 1504 error = ip_pktinfo_prepare(&pktinfo, pktopts, flags, 1505 cred); 1506 if (error) 1507 return error; 1508 break; 1509 case IP_SENDSRCADDR: /* FreeBSD compatibility */ 1510 if (cm->cmsg_len != CMSG_LEN(sizeof(struct in_addr))) 1511 return EINVAL; 1512 pktinfo.ipi_ifindex = 0; 1513 pktinfo.ipi_addr = 1514 ((struct in_pktinfo *)CMSG_DATA(cm))->ipi_addr; 1515 error = ip_pktinfo_prepare(&pktinfo, pktopts, flags, 1516 cred); 1517 if (error) 1518 return error; 1519 break; 1520 default: 1521 return ENOPROTOOPT; 1522 } 1523 } 1524 return 0; 1525 } 1526 1527 /* 1528 * Set up IP options in pcb for insertion in output packets. 1529 * Store in mbuf with pointer in pcbopt, adding pseudo-option 1530 * with destination address if source routed. 1531 */ 1532 static int 1533 ip_pcbopts(struct inpcb *inp, const struct sockopt *sopt) 1534 { 1535 struct mbuf *m; 1536 const u_char *cp; 1537 u_char *dp; 1538 int cnt; 1539 1540 KASSERT(inp_locked(inp)); 1541 1542 /* Turn off any old options. */ 1543 if (inp->inp_options) { 1544 m_free(inp->inp_options); 1545 } 1546 inp->inp_options = NULL; 1547 if ((cnt = sopt->sopt_size) == 0) { 1548 /* Only turning off any previous options. */ 1549 return 0; 1550 } 1551 cp = sopt->sopt_data; 1552 1553 if (cnt % 4) { 1554 /* Must be 4-byte aligned, because there's no padding. */ 1555 return EINVAL; 1556 } 1557 1558 m = m_get(M_DONTWAIT, MT_SOOPTS); 1559 if (m == NULL) 1560 return ENOBUFS; 1561 1562 dp = mtod(m, u_char *); 1563 memset(dp, 0, sizeof(struct in_addr)); 1564 dp += sizeof(struct in_addr); 1565 m->m_len = sizeof(struct in_addr); 1566 1567 /* 1568 * IP option list according to RFC791. Each option is of the form 1569 * 1570 * [optval] [olen] [(olen - 2) data bytes] 1571 * 1572 * We validate the list and copy options to an mbuf for prepending 1573 * to data packets. The IP first-hop destination address will be 1574 * stored before actual options and is zero if unset. 1575 */ 1576 while (cnt > 0) { 1577 uint8_t optval, olen, offset; 1578 1579 optval = cp[IPOPT_OPTVAL]; 1580 1581 if (optval == IPOPT_EOL || optval == IPOPT_NOP) { 1582 olen = 1; 1583 } else { 1584 if (cnt < IPOPT_OLEN + 1) 1585 goto bad; 1586 1587 olen = cp[IPOPT_OLEN]; 1588 if (olen < IPOPT_OLEN + 1 || olen > cnt) 1589 goto bad; 1590 } 1591 1592 if (optval == IPOPT_LSRR || optval == IPOPT_SSRR) { 1593 /* 1594 * user process specifies route as: 1595 * ->A->B->C->D 1596 * D must be our final destination (but we can't 1597 * check that since we may not have connected yet). 1598 * A is first hop destination, which doesn't appear in 1599 * actual IP option, but is stored before the options. 1600 */ 1601 if (olen < IPOPT_OFFSET + 1 + sizeof(struct in_addr)) 1602 goto bad; 1603 1604 offset = cp[IPOPT_OFFSET]; 1605 memcpy(mtod(m, u_char *), cp + IPOPT_OFFSET + 1, 1606 sizeof(struct in_addr)); 1607 1608 cp += sizeof(struct in_addr); 1609 cnt -= sizeof(struct in_addr); 1610 olen -= sizeof(struct in_addr); 1611 1612 if (m->m_len + olen > MAX_IPOPTLEN + sizeof(struct in_addr)) 1613 goto bad; 1614 1615 memcpy(dp, cp, olen); 1616 dp[IPOPT_OPTVAL] = optval; 1617 dp[IPOPT_OLEN] = olen; 1618 dp[IPOPT_OFFSET] = offset; 1619 break; 1620 } else { 1621 if (m->m_len + olen > MAX_IPOPTLEN + sizeof(struct in_addr)) 1622 goto bad; 1623 1624 memcpy(dp, cp, olen); 1625 break; 1626 } 1627 1628 dp += olen; 1629 m->m_len += olen; 1630 1631 if (optval == IPOPT_EOL) 1632 break; 1633 1634 cp += olen; 1635 cnt -= olen; 1636 } 1637 1638 inp->inp_options = m; 1639 return 0; 1640 1641 bad: 1642 (void)m_free(m); 1643 return EINVAL; 1644 } 1645 1646 /* 1647 * following RFC1724 section 3.3, 0.0.0.0/8 is interpreted as interface index. 1648 * Must be called in a pserialize critical section. 1649 */ 1650 static struct ifnet * 1651 ip_multicast_if(struct in_addr *a, int *ifindexp) 1652 { 1653 int ifindex; 1654 struct ifnet *ifp = NULL; 1655 struct in_ifaddr *ia; 1656 1657 if (ifindexp) 1658 *ifindexp = 0; 1659 if (ntohl(a->s_addr) >> 24 == 0) { 1660 ifindex = ntohl(a->s_addr) & 0xffffff; 1661 ifp = if_byindex(ifindex); 1662 if (!ifp) 1663 return NULL; 1664 if (ifindexp) 1665 *ifindexp = ifindex; 1666 } else { 1667 IN_ADDRHASH_READER_FOREACH(ia, a->s_addr) { 1668 if (in_hosteq(ia->ia_addr.sin_addr, *a) && 1669 (ia->ia_ifp->if_flags & IFF_MULTICAST) != 0) { 1670 ifp = ia->ia_ifp; 1671 if (if_is_deactivated(ifp)) 1672 ifp = NULL; 1673 break; 1674 } 1675 } 1676 } 1677 return ifp; 1678 } 1679 1680 static int 1681 ip_getoptval(const struct sockopt *sopt, u_int8_t *val, u_int maxval) 1682 { 1683 u_int tval; 1684 u_char cval; 1685 int error; 1686 1687 if (sopt == NULL) 1688 return EINVAL; 1689 1690 switch (sopt->sopt_size) { 1691 case sizeof(u_char): 1692 error = sockopt_get(sopt, &cval, sizeof(u_char)); 1693 tval = cval; 1694 break; 1695 1696 case sizeof(u_int): 1697 error = sockopt_get(sopt, &tval, sizeof(u_int)); 1698 break; 1699 1700 default: 1701 error = EINVAL; 1702 } 1703 1704 if (error) 1705 return error; 1706 1707 if (tval > maxval) 1708 return EINVAL; 1709 1710 *val = tval; 1711 return 0; 1712 } 1713 1714 static int 1715 ip_get_membership(const struct sockopt *sopt, struct ifnet **ifp, 1716 struct psref *psref, struct in_addr *ia, bool add) 1717 { 1718 int error; 1719 struct ip_mreq mreq; 1720 1721 error = sockopt_get(sopt, &mreq, sizeof(mreq)); 1722 if (error) 1723 return error; 1724 1725 if (!IN_MULTICAST(mreq.imr_multiaddr.s_addr)) 1726 return EINVAL; 1727 1728 memcpy(ia, &mreq.imr_multiaddr, sizeof(*ia)); 1729 1730 if (in_nullhost(mreq.imr_interface)) { 1731 union { 1732 struct sockaddr dst; 1733 struct sockaddr_in dst4; 1734 } u; 1735 struct route ro; 1736 1737 if (!add) { 1738 *ifp = NULL; 1739 return 0; 1740 } 1741 /* 1742 * If no interface address was provided, use the interface of 1743 * the route to the given multicast address. 1744 */ 1745 struct rtentry *rt; 1746 memset(&ro, 0, sizeof(ro)); 1747 1748 sockaddr_in_init(&u.dst4, ia, 0); 1749 error = rtcache_setdst(&ro, &u.dst); 1750 if (error != 0) 1751 return error; 1752 *ifp = (rt = rtcache_init(&ro)) != NULL ? rt->rt_ifp : NULL; 1753 if (*ifp != NULL) { 1754 if (if_is_deactivated(*ifp)) 1755 *ifp = NULL; 1756 else 1757 if_acquire(*ifp, psref); 1758 } 1759 rtcache_unref(rt, &ro); 1760 rtcache_free(&ro); 1761 } else { 1762 int s = pserialize_read_enter(); 1763 *ifp = ip_multicast_if(&mreq.imr_interface, NULL); 1764 if (!add && *ifp == NULL) { 1765 pserialize_read_exit(s); 1766 return EADDRNOTAVAIL; 1767 } 1768 if (*ifp != NULL) { 1769 if (if_is_deactivated(*ifp)) 1770 *ifp = NULL; 1771 else 1772 if_acquire(*ifp, psref); 1773 } 1774 pserialize_read_exit(s); 1775 } 1776 return 0; 1777 } 1778 1779 /* 1780 * Add a multicast group membership. 1781 * Group must be a valid IP multicast address. 1782 */ 1783 static int 1784 ip_add_membership(struct ip_moptions *imo, const struct sockopt *sopt) 1785 { 1786 struct ifnet *ifp = NULL; // XXX: gcc [ppc] 1787 struct in_addr ia; 1788 int i, error, bound; 1789 struct psref psref; 1790 1791 /* imo is protected by solock or referenced only by the caller */ 1792 1793 bound = curlwp_bind(); 1794 if (sopt->sopt_size == sizeof(struct ip_mreq)) 1795 error = ip_get_membership(sopt, &ifp, &psref, &ia, true); 1796 else { 1797 #ifdef INET6 1798 error = ip6_get_membership(sopt, &ifp, &psref, &ia, sizeof(ia)); 1799 #else 1800 error = EINVAL; 1801 #endif 1802 } 1803 1804 if (error) 1805 goto out; 1806 1807 /* 1808 * See if we found an interface, and confirm that it 1809 * supports multicast. 1810 */ 1811 if (ifp == NULL || (ifp->if_flags & IFF_MULTICAST) == 0) { 1812 error = EADDRNOTAVAIL; 1813 goto out; 1814 } 1815 1816 /* 1817 * See if the membership already exists or if all the 1818 * membership slots are full. 1819 */ 1820 for (i = 0; i < imo->imo_num_memberships; ++i) { 1821 if (imo->imo_membership[i]->inm_ifp == ifp && 1822 in_hosteq(imo->imo_membership[i]->inm_addr, ia)) 1823 break; 1824 } 1825 if (i < imo->imo_num_memberships) { 1826 error = EADDRINUSE; 1827 goto out; 1828 } 1829 1830 if (i == IP_MAX_MEMBERSHIPS) { 1831 error = ETOOMANYREFS; 1832 goto out; 1833 } 1834 1835 /* 1836 * Everything looks good; add a new record to the multicast 1837 * address list for the given interface. 1838 */ 1839 IFNET_LOCK(ifp); 1840 imo->imo_membership[i] = in_addmulti(&ia, ifp); 1841 IFNET_UNLOCK(ifp); 1842 if (imo->imo_membership[i] == NULL) { 1843 error = ENOBUFS; 1844 goto out; 1845 } 1846 1847 ++imo->imo_num_memberships; 1848 error = 0; 1849 out: 1850 if_put(ifp, &psref); 1851 curlwp_bindx(bound); 1852 return error; 1853 } 1854 1855 /* 1856 * Drop a multicast group membership. 1857 * Group must be a valid IP multicast address. 1858 */ 1859 static int 1860 ip_drop_membership(struct ip_moptions *imo, const struct sockopt *sopt) 1861 { 1862 struct in_addr ia = { .s_addr = 0 }; // XXX: gcc [ppc] 1863 struct ifnet *ifp = NULL; // XXX: gcc [ppc] 1864 int i, error, bound; 1865 struct psref psref; 1866 1867 /* imo is protected by solock or referenced only by the caller */ 1868 1869 bound = curlwp_bind(); 1870 if (sopt->sopt_size == sizeof(struct ip_mreq)) 1871 error = ip_get_membership(sopt, &ifp, &psref, &ia, false); 1872 else { 1873 #ifdef INET6 1874 error = ip6_get_membership(sopt, &ifp, &psref, &ia, sizeof(ia)); 1875 #else 1876 error = EINVAL; 1877 #endif 1878 } 1879 1880 if (error) 1881 goto out; 1882 1883 /* 1884 * Find the membership in the membership array. 1885 */ 1886 for (i = 0; i < imo->imo_num_memberships; ++i) { 1887 if ((ifp == NULL || 1888 imo->imo_membership[i]->inm_ifp == ifp) && 1889 in_hosteq(imo->imo_membership[i]->inm_addr, ia)) 1890 break; 1891 } 1892 if (i == imo->imo_num_memberships) { 1893 error = EADDRNOTAVAIL; 1894 goto out; 1895 } 1896 1897 /* 1898 * Give up the multicast address record to which the 1899 * membership points. 1900 */ 1901 struct ifnet *inm_ifp = imo->imo_membership[i]->inm_ifp; 1902 IFNET_LOCK(inm_ifp); 1903 in_delmulti(imo->imo_membership[i]); 1904 IFNET_UNLOCK(inm_ifp); 1905 1906 /* 1907 * Remove the gap in the membership array. 1908 */ 1909 for (++i; i < imo->imo_num_memberships; ++i) 1910 imo->imo_membership[i-1] = imo->imo_membership[i]; 1911 --imo->imo_num_memberships; 1912 error = 0; 1913 out: 1914 if_put(ifp, &psref); 1915 curlwp_bindx(bound); 1916 return error; 1917 } 1918 1919 /* 1920 * Set the IP multicast options in response to user setsockopt(). 1921 */ 1922 int 1923 ip_setmoptions(struct ip_moptions **pimo, const struct sockopt *sopt) 1924 { 1925 struct ip_moptions *imo = *pimo; 1926 struct in_addr addr; 1927 struct ifnet *ifp; 1928 int ifindex, error = 0; 1929 1930 /* The passed imo isn't NULL, it should be protected by solock */ 1931 1932 if (!imo) { 1933 /* 1934 * No multicast option buffer attached to the pcb; 1935 * allocate one and initialize to default values. 1936 */ 1937 imo = kmem_intr_alloc(sizeof(*imo), KM_NOSLEEP); 1938 if (imo == NULL) 1939 return ENOBUFS; 1940 1941 imo->imo_multicast_if_index = 0; 1942 imo->imo_multicast_addr.s_addr = INADDR_ANY; 1943 imo->imo_multicast_ttl = IP_DEFAULT_MULTICAST_TTL; 1944 imo->imo_multicast_loop = IP_DEFAULT_MULTICAST_LOOP; 1945 imo->imo_num_memberships = 0; 1946 *pimo = imo; 1947 } 1948 1949 switch (sopt->sopt_name) { 1950 case IP_MULTICAST_IF: { 1951 int s; 1952 /* 1953 * Select the interface for outgoing multicast packets. 1954 */ 1955 error = sockopt_get(sopt, &addr, sizeof(addr)); 1956 if (error) 1957 break; 1958 1959 /* 1960 * INADDR_ANY is used to remove a previous selection. 1961 * When no interface is selected, a default one is 1962 * chosen every time a multicast packet is sent. 1963 */ 1964 if (in_nullhost(addr)) { 1965 imo->imo_multicast_if_index = 0; 1966 break; 1967 } 1968 /* 1969 * The selected interface is identified by its local 1970 * IP address. Find the interface and confirm that 1971 * it supports multicasting. 1972 */ 1973 s = pserialize_read_enter(); 1974 ifp = ip_multicast_if(&addr, &ifindex); 1975 if (ifp == NULL || (ifp->if_flags & IFF_MULTICAST) == 0) { 1976 pserialize_read_exit(s); 1977 error = EADDRNOTAVAIL; 1978 break; 1979 } 1980 imo->imo_multicast_if_index = ifp->if_index; 1981 pserialize_read_exit(s); 1982 if (ifindex) 1983 imo->imo_multicast_addr = addr; 1984 else 1985 imo->imo_multicast_addr.s_addr = INADDR_ANY; 1986 break; 1987 } 1988 1989 case IP_MULTICAST_TTL: 1990 /* 1991 * Set the IP time-to-live for outgoing multicast packets. 1992 */ 1993 error = ip_getoptval(sopt, &imo->imo_multicast_ttl, MAXTTL); 1994 break; 1995 1996 case IP_MULTICAST_LOOP: 1997 /* 1998 * Set the loopback flag for outgoing multicast packets. 1999 * Must be zero or one. 2000 */ 2001 error = ip_getoptval(sopt, &imo->imo_multicast_loop, 1); 2002 break; 2003 2004 case IP_ADD_MEMBERSHIP: /* IPV6_JOIN_GROUP */ 2005 error = ip_add_membership(imo, sopt); 2006 break; 2007 2008 case IP_DROP_MEMBERSHIP: /* IPV6_LEAVE_GROUP */ 2009 error = ip_drop_membership(imo, sopt); 2010 break; 2011 2012 default: 2013 error = EOPNOTSUPP; 2014 break; 2015 } 2016 2017 /* 2018 * If all options have default values, no need to keep the mbuf. 2019 */ 2020 if (imo->imo_multicast_if_index == 0 && 2021 imo->imo_multicast_ttl == IP_DEFAULT_MULTICAST_TTL && 2022 imo->imo_multicast_loop == IP_DEFAULT_MULTICAST_LOOP && 2023 imo->imo_num_memberships == 0) { 2024 kmem_intr_free(imo, sizeof(*imo)); 2025 *pimo = NULL; 2026 } 2027 2028 return error; 2029 } 2030 2031 /* 2032 * Return the IP multicast options in response to user getsockopt(). 2033 */ 2034 int 2035 ip_getmoptions(struct ip_moptions *imo, struct sockopt *sopt) 2036 { 2037 struct in_addr addr; 2038 uint8_t optval; 2039 int error = 0; 2040 2041 /* imo is protected by solock or refereced only by the caller */ 2042 2043 switch (sopt->sopt_name) { 2044 case IP_MULTICAST_IF: 2045 if (imo == NULL || imo->imo_multicast_if_index == 0) 2046 addr = zeroin_addr; 2047 else if (imo->imo_multicast_addr.s_addr) { 2048 /* return the value user has set */ 2049 addr = imo->imo_multicast_addr; 2050 } else { 2051 struct ifnet *ifp; 2052 struct in_ifaddr *ia = NULL; 2053 int s = pserialize_read_enter(); 2054 2055 ifp = if_byindex(imo->imo_multicast_if_index); 2056 if (ifp != NULL) { 2057 ia = in_get_ia_from_ifp(ifp); 2058 } 2059 addr = ia ? ia->ia_addr.sin_addr : zeroin_addr; 2060 pserialize_read_exit(s); 2061 } 2062 error = sockopt_set(sopt, &addr, sizeof(addr)); 2063 break; 2064 2065 case IP_MULTICAST_TTL: 2066 optval = imo ? imo->imo_multicast_ttl 2067 : IP_DEFAULT_MULTICAST_TTL; 2068 2069 error = sockopt_set(sopt, &optval, sizeof(optval)); 2070 break; 2071 2072 case IP_MULTICAST_LOOP: 2073 optval = imo ? imo->imo_multicast_loop 2074 : IP_DEFAULT_MULTICAST_LOOP; 2075 2076 error = sockopt_set(sopt, &optval, sizeof(optval)); 2077 break; 2078 2079 default: 2080 error = EOPNOTSUPP; 2081 } 2082 2083 return error; 2084 } 2085 2086 /* 2087 * Discard the IP multicast options. 2088 */ 2089 void 2090 ip_freemoptions(struct ip_moptions *imo) 2091 { 2092 int i; 2093 2094 /* The owner of imo (inp) should be protected by solock */ 2095 2096 if (imo != NULL) { 2097 for (i = 0; i < imo->imo_num_memberships; ++i) { 2098 struct in_multi *inm = imo->imo_membership[i]; 2099 struct ifnet *ifp = inm->inm_ifp; 2100 IFNET_LOCK(ifp); 2101 in_delmulti(inm); 2102 /* ifp should not leave thanks to solock */ 2103 IFNET_UNLOCK(ifp); 2104 } 2105 2106 kmem_intr_free(imo, sizeof(*imo)); 2107 } 2108 } 2109 2110 /* 2111 * Routine called from ip_output() to loop back a copy of an IP multicast 2112 * packet to the input queue of a specified interface. Note that this 2113 * calls the output routine of the loopback "driver", but with an interface 2114 * pointer that might NOT be lo0ifp -- easier than replicating that code here. 2115 */ 2116 static void 2117 ip_mloopback(struct ifnet *ifp, struct mbuf *m, const struct sockaddr_in *dst) 2118 { 2119 struct ip *ip; 2120 struct mbuf *copym; 2121 2122 copym = m_copypacket(m, M_DONTWAIT); 2123 if (copym != NULL && 2124 (copym->m_flags & M_EXT || copym->m_len < sizeof(struct ip))) 2125 copym = m_pullup(copym, sizeof(struct ip)); 2126 if (copym == NULL) 2127 return; 2128 /* 2129 * We don't bother to fragment if the IP length is greater 2130 * than the interface's MTU. Can this possibly matter? 2131 */ 2132 ip = mtod(copym, struct ip *); 2133 2134 if (copym->m_pkthdr.csum_flags & (M_CSUM_TCPv4|M_CSUM_UDPv4)) { 2135 in_undefer_cksum_tcpudp(copym); 2136 copym->m_pkthdr.csum_flags &= 2137 ~(M_CSUM_TCPv4|M_CSUM_UDPv4); 2138 } 2139 2140 ip->ip_sum = 0; 2141 ip->ip_sum = in_cksum(copym, ip->ip_hl << 2); 2142 KERNEL_LOCK_UNLESS_NET_MPSAFE(); 2143 (void)looutput(ifp, copym, sintocsa(dst), NULL); 2144 KERNEL_UNLOCK_UNLESS_NET_MPSAFE(); 2145 } 2146 2147 /* 2148 * Ensure sending address is valid. 2149 * Returns 0 on success, -1 if an error should be sent back or 1 2150 * if the packet could be dropped without error (protocol dependent). 2151 */ 2152 static int 2153 ip_ifaddrvalid(const struct in_ifaddr *ia) 2154 { 2155 2156 if (ia->ia_addr.sin_addr.s_addr == INADDR_ANY) 2157 return 0; 2158 2159 if (ia->ia4_flags & IN_IFF_DUPLICATED) 2160 return -1; 2161 else if (ia->ia4_flags & (IN_IFF_TENTATIVE | IN_IFF_DETACHED)) 2162 return 1; 2163 2164 return 0; 2165 } 2166
Indexes created Wed Oct 01 12:09:54 GMT 2025