ip_output.c revision 1.291
1 /* $NetBSD: ip_output.c,v 1.291 2018/01/10 17:36:06 christos 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 1.291 2018/01/10 17:36:06 christos 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 hlen = sizeof (struct ip); 236 int len, 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; 256 257 len = 0; 258 259 MCLAIM(m, &ip_tx_mowner); 260 261 KASSERT((m->m_flags & M_PKTHDR) != 0); 262 KASSERT((m->m_pkthdr.csum_flags & (M_CSUM_TCPv6|M_CSUM_UDPv6)) == 0); 263 KASSERT((m->m_pkthdr.csum_flags & (M_CSUM_TCPv4|M_CSUM_UDPv4)) != 264 (M_CSUM_TCPv4|M_CSUM_UDPv4)); 265 266 if (opt) { 267 m = ip_insertoptions(m, opt, &len); 268 if (len >= sizeof(struct ip)) 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 * RFC 1112 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 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 /* 581 * TSO capable interfaces (typically?) increment 582 * ip_id for each segment. 583 * "allocate" enough ids here to increase the chance 584 * for them to be unique. 585 * 586 * note that the following calculation is not 587 * needed to be precise. wasting some ip_id is fine. 588 */ 589 590 unsigned int segsz = m->m_pkthdr.segsz; 591 unsigned int datasz = ntohs(ip->ip_len) - hlen; 592 unsigned int num = howmany(datasz, segsz); 593 594 ip->ip_id = ip_newid_range(ia, num); 595 } 596 } 597 if (ia != NULL) { 598 ia4_release(ia, &psref_ia); 599 ia = NULL; 600 } 601 602 /* 603 * If we're doing Path MTU Discovery, we need to set DF unless 604 * the route's MTU is locked. 605 */ 606 if ((flags & IP_MTUDISC) != 0 && rtmtu_nolock) { 607 ip->ip_off |= htons(IP_DF); 608 } 609 610 #ifdef IPSEC 611 if (ipsec_used) { 612 bool ipsec_done = false; 613 614 /* Perform IPsec processing, if any. */ 615 error = ipsec4_output(m, inp, flags, &mtu, &natt_frag, 616 &ipsec_done); 617 if (error || ipsec_done) 618 goto done; 619 } 620 #endif 621 622 /* 623 * Run through list of hooks for output packets. 624 */ 625 error = pfil_run_hooks(inet_pfil_hook, &m, ifp, PFIL_OUT); 626 if (error) 627 goto done; 628 if (m == NULL) 629 goto done; 630 631 ip = mtod(m, struct ip *); 632 hlen = ip->ip_hl << 2; 633 634 m->m_pkthdr.csum_data |= hlen << 16; 635 636 /* 637 * search for the source address structure to 638 * maintain output statistics, and verify address 639 * validity 640 */ 641 KASSERT(ia == NULL); 642 sockaddr_in_init(&usrc.sin, &ip->ip_src, 0); 643 ifa = ifaof_ifpforaddr_psref(&usrc.sa, ifp, &psref_ia); 644 if (ifa != NULL) 645 ia = ifatoia(ifa); 646 647 /* 648 * Ensure we only send from a valid address. 649 * A NULL address is valid because the packet could be 650 * generated from a packet filter. 651 */ 652 if (ia != NULL && (flags & IP_FORWARDING) == 0 && 653 (error = ip_ifaddrvalid(ia)) != 0) 654 { 655 ARPLOG(LOG_ERR, 656 "refusing to send from invalid address %s (pid %d)\n", 657 ARPLOGADDR(&ip->ip_src), curproc->p_pid); 658 IP_STATINC(IP_STAT_ODROPPED); 659 if (error == 1) 660 /* 661 * Address exists, but is tentative or detached. 662 * We can't send from it because it's invalid, 663 * so we drop the packet. 664 */ 665 error = 0; 666 else 667 error = EADDRNOTAVAIL; 668 goto bad; 669 } 670 671 /* Maybe skip checksums on loopback interfaces. */ 672 if (IN_NEED_CHECKSUM(ifp, M_CSUM_IPv4)) { 673 m->m_pkthdr.csum_flags |= M_CSUM_IPv4; 674 } 675 sw_csum = m->m_pkthdr.csum_flags & ~ifp->if_csum_flags_tx; 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_delayed_cksum(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 730 * fragment the packet. 731 * 732 * XXX Some hardware can do this. 733 */ 734 if (m->m_pkthdr.csum_flags & (M_CSUM_TCPv4|M_CSUM_UDPv4)) { 735 if (IN_NEED_CHECKSUM(ifp, 736 m->m_pkthdr.csum_flags & (M_CSUM_TCPv4|M_CSUM_UDPv4))) { 737 in_delayed_cksum(m); 738 } 739 m->m_pkthdr.csum_flags &= ~(M_CSUM_TCPv4|M_CSUM_UDPv4); 740 } 741 742 /* 743 * Too large for interface; fragment if possible. 744 * Must be able to put at least 8 bytes per fragment. 745 */ 746 if (ntohs(ip->ip_off) & IP_DF) { 747 if (flags & IP_RETURNMTU) { 748 KASSERT(inp != NULL); 749 inp->inp_errormtu = mtu; 750 } 751 error = EMSGSIZE; 752 IP_STATINC(IP_STAT_CANTFRAG); 753 goto bad; 754 } 755 756 error = ip_fragment(m, ifp, mtu); 757 if (error) { 758 m = NULL; 759 goto bad; 760 } 761 762 for (; m; m = m0) { 763 m0 = m->m_nextpkt; 764 m->m_nextpkt = 0; 765 if (error) { 766 m_freem(m); 767 continue; 768 } 769 #if IFA_STATS 770 if (ia) 771 ia->ia_ifa.ifa_data.ifad_outbytes += ntohs(ip->ip_len); 772 #endif 773 /* 774 * If we get there, the packet has not been handled by 775 * IPsec whereas it should have. Now that it has been 776 * fragmented, re-inject it in ip_output so that IPsec 777 * processing can occur. 778 */ 779 if (natt_frag) { 780 error = ip_output(m, opt, ro, 781 flags | IP_RAWOUTPUT | IP_NOIPNEWID, 782 imo, inp); 783 } else { 784 KASSERT((m->m_pkthdr.csum_flags & 785 (M_CSUM_UDPv4 | M_CSUM_TCPv4)) == 0); 786 error = ip_if_output(ifp, m, 787 (m->m_flags & M_MCAST) ? 788 sintocsa(rdst) : sintocsa(dst), rt); 789 } 790 } 791 if (error == 0) { 792 IP_STATINC(IP_STAT_FRAGMENTED); 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 bad: 807 m_freem(m); 808 goto done; 809 } 810 811 int 812 ip_fragment(struct mbuf *m, struct ifnet *ifp, u_long mtu) 813 { 814 struct ip *ip, *mhip; 815 struct mbuf *m0; 816 int len, hlen, off; 817 int mhlen, firstlen; 818 struct mbuf **mnext; 819 int sw_csum = m->m_pkthdr.csum_flags; 820 int fragments = 0; 821 int error = 0; 822 823 ip = mtod(m, struct ip *); 824 hlen = ip->ip_hl << 2; 825 if (ifp != NULL) 826 sw_csum &= ~ifp->if_csum_flags_tx; 827 828 len = (mtu - hlen) &~ 7; 829 if (len < 8) { 830 m_freem(m); 831 return (EMSGSIZE); 832 } 833 834 firstlen = len; 835 mnext = &m->m_nextpkt; 836 837 /* 838 * Loop through length of segment after first fragment, 839 * make new header and copy data of each part and link onto chain. 840 */ 841 m0 = m; 842 mhlen = sizeof (struct ip); 843 for (off = hlen + len; off < ntohs(ip->ip_len); off += len) { 844 MGETHDR(m, M_DONTWAIT, MT_HEADER); 845 if (m == 0) { 846 error = ENOBUFS; 847 IP_STATINC(IP_STAT_ODROPPED); 848 goto sendorfree; 849 } 850 MCLAIM(m, m0->m_owner); 851 *mnext = m; 852 mnext = &m->m_nextpkt; 853 m->m_data += max_linkhdr; 854 mhip = mtod(m, struct ip *); 855 *mhip = *ip; 856 /* we must inherit MCAST and BCAST flags */ 857 m->m_flags |= m0->m_flags & (M_MCAST|M_BCAST); 858 if (hlen > sizeof (struct ip)) { 859 mhlen = ip_optcopy(ip, mhip) + sizeof (struct ip); 860 mhip->ip_hl = mhlen >> 2; 861 } 862 m->m_len = mhlen; 863 mhip->ip_off = ((off - hlen) >> 3) + 864 (ntohs(ip->ip_off) & ~IP_MF); 865 if (ip->ip_off & htons(IP_MF)) 866 mhip->ip_off |= IP_MF; 867 if (off + len >= ntohs(ip->ip_len)) 868 len = ntohs(ip->ip_len) - off; 869 else 870 mhip->ip_off |= IP_MF; 871 HTONS(mhip->ip_off); 872 mhip->ip_len = htons((u_int16_t)(len + mhlen)); 873 m->m_next = m_copym(m0, off, len, M_DONTWAIT); 874 if (m->m_next == 0) { 875 error = ENOBUFS; /* ??? */ 876 IP_STATINC(IP_STAT_ODROPPED); 877 goto sendorfree; 878 } 879 m->m_pkthdr.len = mhlen + len; 880 m_reset_rcvif(m); 881 mhip->ip_sum = 0; 882 KASSERT((m->m_pkthdr.csum_flags & M_CSUM_IPv4) == 0); 883 if (sw_csum & M_CSUM_IPv4) { 884 mhip->ip_sum = in_cksum(m, mhlen); 885 } else { 886 /* 887 * checksum is hw-offloaded or not necessary. 888 */ 889 m->m_pkthdr.csum_flags |= 890 m0->m_pkthdr.csum_flags & M_CSUM_IPv4; 891 m->m_pkthdr.csum_data |= mhlen << 16; 892 KASSERT(!(ifp != NULL && 893 IN_NEED_CHECKSUM(ifp, M_CSUM_IPv4)) || 894 (m->m_pkthdr.csum_flags & M_CSUM_IPv4) != 0); 895 } 896 IP_STATINC(IP_STAT_OFRAGMENTS); 897 fragments++; 898 } 899 /* 900 * Update first fragment by trimming what's been copied out 901 * and updating header, then send each fragment (in order). 902 */ 903 m = m0; 904 m_adj(m, hlen + firstlen - ntohs(ip->ip_len)); 905 m->m_pkthdr.len = hlen + firstlen; 906 ip->ip_len = htons((u_int16_t)m->m_pkthdr.len); 907 ip->ip_off |= htons(IP_MF); 908 ip->ip_sum = 0; 909 if (sw_csum & M_CSUM_IPv4) { 910 ip->ip_sum = in_cksum(m, hlen); 911 m->m_pkthdr.csum_flags &= ~M_CSUM_IPv4; 912 } else { 913 /* 914 * checksum is hw-offloaded or not necessary. 915 */ 916 KASSERT(!(ifp != NULL && IN_NEED_CHECKSUM(ifp, M_CSUM_IPv4)) || 917 (m->m_pkthdr.csum_flags & M_CSUM_IPv4) != 0); 918 KASSERT(M_CSUM_DATA_IPv4_IPHL(m->m_pkthdr.csum_data) >= 919 sizeof(struct ip)); 920 } 921 sendorfree: 922 /* 923 * If there is no room for all the fragments, don't queue 924 * any of them. 925 */ 926 if (ifp != NULL) { 927 IFQ_LOCK(&ifp->if_snd); 928 if (ifp->if_snd.ifq_maxlen - ifp->if_snd.ifq_len < fragments && 929 error == 0) { 930 error = ENOBUFS; 931 IP_STATINC(IP_STAT_ODROPPED); 932 IFQ_INC_DROPS(&ifp->if_snd); 933 } 934 IFQ_UNLOCK(&ifp->if_snd); 935 } 936 if (error) { 937 for (m = m0; m; m = m0) { 938 m0 = m->m_nextpkt; 939 m->m_nextpkt = NULL; 940 m_freem(m); 941 } 942 } 943 return (error); 944 } 945 946 /* 947 * Process a delayed payload checksum calculation. 948 */ 949 void 950 in_delayed_cksum(struct mbuf *m) 951 { 952 struct ip *ip; 953 u_int16_t csum, offset; 954 955 ip = mtod(m, struct ip *); 956 offset = ip->ip_hl << 2; 957 csum = in4_cksum(m, 0, offset, ntohs(ip->ip_len) - offset); 958 if (csum == 0 && (m->m_pkthdr.csum_flags & M_CSUM_UDPv4) != 0) 959 csum = 0xffff; 960 961 offset += M_CSUM_DATA_IPv4_OFFSET(m->m_pkthdr.csum_data); 962 963 if ((offset + sizeof(u_int16_t)) > m->m_len) { 964 /* This happen when ip options were inserted 965 printf("in_delayed_cksum: pullup len %d off %d proto %d\n", 966 m->m_len, offset, ip->ip_p); 967 */ 968 m_copyback(m, offset, sizeof(csum), (void *) &csum); 969 } else 970 *(u_int16_t *)(mtod(m, char *) + offset) = csum; 971 } 972 973 /* 974 * Determine the maximum length of the options to be inserted; 975 * we would far rather allocate too much space rather than too little. 976 */ 977 978 u_int 979 ip_optlen(struct inpcb *inp) 980 { 981 struct mbuf *m = inp->inp_options; 982 983 if (m && m->m_len > offsetof(struct ipoption, ipopt_dst)) { 984 return (m->m_len - offsetof(struct ipoption, ipopt_dst)); 985 } 986 return 0; 987 } 988 989 /* 990 * Insert IP options into preformed packet. 991 * Adjust IP destination as required for IP source routing, 992 * as indicated by a non-zero in_addr at the start of the options. 993 */ 994 static struct mbuf * 995 ip_insertoptions(struct mbuf *m, struct mbuf *opt, int *phlen) 996 { 997 struct ipoption *p = mtod(opt, struct ipoption *); 998 struct mbuf *n; 999 struct ip *ip = mtod(m, struct ip *); 1000 unsigned optlen; 1001 1002 optlen = opt->m_len - sizeof(p->ipopt_dst); 1003 if (optlen + ntohs(ip->ip_len) > IP_MAXPACKET) 1004 return (m); /* XXX should fail */ 1005 if (!in_nullhost(p->ipopt_dst)) 1006 ip->ip_dst = p->ipopt_dst; 1007 if (M_READONLY(m) || M_LEADINGSPACE(m) < optlen) { 1008 MGETHDR(n, M_DONTWAIT, MT_HEADER); 1009 if (n == 0) 1010 return (m); 1011 MCLAIM(n, m->m_owner); 1012 M_MOVE_PKTHDR(n, m); 1013 m->m_len -= sizeof(struct ip); 1014 m->m_data += sizeof(struct ip); 1015 n->m_next = m; 1016 m = n; 1017 m->m_len = optlen + sizeof(struct ip); 1018 m->m_data += max_linkhdr; 1019 bcopy((void *)ip, mtod(m, void *), sizeof(struct ip)); 1020 } else { 1021 m->m_data -= optlen; 1022 m->m_len += optlen; 1023 memmove(mtod(m, void *), ip, sizeof(struct ip)); 1024 } 1025 m->m_pkthdr.len += optlen; 1026 ip = mtod(m, struct ip *); 1027 bcopy((void *)p->ipopt_list, (void *)(ip + 1), (unsigned)optlen); 1028 *phlen = sizeof(struct ip) + optlen; 1029 ip->ip_len = htons(ntohs(ip->ip_len) + optlen); 1030 return (m); 1031 } 1032 1033 /* 1034 * Copy options from ip to jp, 1035 * omitting those not copied during fragmentation. 1036 */ 1037 int 1038 ip_optcopy(struct ip *ip, struct ip *jp) 1039 { 1040 u_char *cp, *dp; 1041 int opt, optlen, cnt; 1042 1043 cp = (u_char *)(ip + 1); 1044 dp = (u_char *)(jp + 1); 1045 cnt = (ip->ip_hl << 2) - sizeof (struct ip); 1046 for (; cnt > 0; cnt -= optlen, cp += optlen) { 1047 opt = cp[0]; 1048 if (opt == IPOPT_EOL) 1049 break; 1050 if (opt == IPOPT_NOP) { 1051 /* Preserve for IP mcast tunnel's LSRR alignment. */ 1052 *dp++ = IPOPT_NOP; 1053 optlen = 1; 1054 continue; 1055 } 1056 1057 KASSERT(cnt >= IPOPT_OLEN + sizeof(*cp)); 1058 optlen = cp[IPOPT_OLEN]; 1059 KASSERT(optlen >= IPOPT_OLEN + sizeof(*cp) && optlen < cnt); 1060 1061 /* Invalid lengths should have been caught by ip_dooptions. */ 1062 if (optlen > cnt) 1063 optlen = cnt; 1064 if (IPOPT_COPIED(opt)) { 1065 bcopy((void *)cp, (void *)dp, (unsigned)optlen); 1066 dp += optlen; 1067 } 1068 } 1069 for (optlen = dp - (u_char *)(jp+1); optlen & 0x3; optlen++) 1070 *dp++ = IPOPT_EOL; 1071 return (optlen); 1072 } 1073 1074 /* 1075 * IP socket option processing. 1076 */ 1077 int 1078 ip_ctloutput(int op, struct socket *so, struct sockopt *sopt) 1079 { 1080 struct inpcb *inp = sotoinpcb(so); 1081 struct ip *ip = &inp->inp_ip; 1082 int inpflags = inp->inp_flags; 1083 int optval = 0, error = 0; 1084 struct in_pktinfo pktinfo; 1085 1086 KASSERT(solocked(so)); 1087 1088 if (sopt->sopt_level != IPPROTO_IP) { 1089 if (sopt->sopt_level == SOL_SOCKET && sopt->sopt_name == SO_NOHEADER) 1090 return 0; 1091 return ENOPROTOOPT; 1092 } 1093 1094 switch (op) { 1095 case PRCO_SETOPT: 1096 switch (sopt->sopt_name) { 1097 case IP_OPTIONS: 1098 #ifdef notyet 1099 case IP_RETOPTS: 1100 #endif 1101 error = ip_pcbopts(inp, sopt); 1102 break; 1103 1104 case IP_TOS: 1105 case IP_TTL: 1106 case IP_MINTTL: 1107 case IP_RECVOPTS: 1108 case IP_RECVRETOPTS: 1109 case IP_RECVDSTADDR: 1110 case IP_RECVIF: 1111 case IP_RECVPKTINFO: 1112 case IP_RECVTTL: 1113 error = sockopt_getint(sopt, &optval); 1114 if (error) 1115 break; 1116 1117 switch (sopt->sopt_name) { 1118 case IP_TOS: 1119 ip->ip_tos = optval; 1120 break; 1121 1122 case IP_TTL: 1123 ip->ip_ttl = optval; 1124 break; 1125 1126 case IP_MINTTL: 1127 if (optval > 0 && optval <= MAXTTL) 1128 inp->inp_ip_minttl = optval; 1129 else 1130 error = EINVAL; 1131 break; 1132 #define OPTSET(bit) \ 1133 if (optval) \ 1134 inpflags |= bit; \ 1135 else \ 1136 inpflags &= ~bit; 1137 1138 case IP_RECVOPTS: 1139 OPTSET(INP_RECVOPTS); 1140 break; 1141 1142 case IP_RECVPKTINFO: 1143 OPTSET(INP_RECVPKTINFO); 1144 break; 1145 1146 case IP_RECVRETOPTS: 1147 OPTSET(INP_RECVRETOPTS); 1148 break; 1149 1150 case IP_RECVDSTADDR: 1151 OPTSET(INP_RECVDSTADDR); 1152 break; 1153 1154 case IP_RECVIF: 1155 OPTSET(INP_RECVIF); 1156 break; 1157 1158 case IP_RECVTTL: 1159 OPTSET(INP_RECVTTL); 1160 break; 1161 } 1162 break; 1163 case IP_PKTINFO: 1164 error = sockopt_getint(sopt, &optval); 1165 if (!error) { 1166 /* Linux compatibility */ 1167 OPTSET(INP_RECVPKTINFO); 1168 break; 1169 } 1170 error = sockopt_get(sopt, &pktinfo, sizeof(pktinfo)); 1171 if (error) 1172 break; 1173 1174 if (pktinfo.ipi_ifindex == 0) { 1175 inp->inp_prefsrcip = pktinfo.ipi_addr; 1176 break; 1177 } 1178 1179 /* Solaris compatibility */ 1180 struct ifnet *ifp; 1181 struct in_ifaddr *ia; 1182 int s; 1183 1184 /* pick up primary address */ 1185 s = pserialize_read_enter(); 1186 ifp = if_byindex(pktinfo.ipi_ifindex); 1187 if (ifp == NULL) { 1188 pserialize_read_exit(s); 1189 error = EADDRNOTAVAIL; 1190 break; 1191 } 1192 ia = in_get_ia_from_ifp(ifp); 1193 if (ia == NULL) { 1194 pserialize_read_exit(s); 1195 error = EADDRNOTAVAIL; 1196 break; 1197 } 1198 inp->inp_prefsrcip = IA_SIN(ia)->sin_addr; 1199 pserialize_read_exit(s); 1200 break; 1201 break; 1202 #undef OPTSET 1203 1204 case IP_MULTICAST_IF: 1205 case IP_MULTICAST_TTL: 1206 case IP_MULTICAST_LOOP: 1207 case IP_ADD_MEMBERSHIP: 1208 case IP_DROP_MEMBERSHIP: 1209 error = ip_setmoptions(&inp->inp_moptions, sopt); 1210 break; 1211 1212 case IP_PORTRANGE: 1213 error = sockopt_getint(sopt, &optval); 1214 if (error) 1215 break; 1216 1217 switch (optval) { 1218 case IP_PORTRANGE_DEFAULT: 1219 case IP_PORTRANGE_HIGH: 1220 inpflags &= ~(INP_LOWPORT); 1221 break; 1222 1223 case IP_PORTRANGE_LOW: 1224 inpflags |= INP_LOWPORT; 1225 break; 1226 1227 default: 1228 error = EINVAL; 1229 break; 1230 } 1231 break; 1232 1233 case IP_PORTALGO: 1234 error = sockopt_getint(sopt, &optval); 1235 if (error) 1236 break; 1237 1238 error = portalgo_algo_index_select( 1239 (struct inpcb_hdr *)inp, optval); 1240 break; 1241 1242 #if defined(IPSEC) 1243 case IP_IPSEC_POLICY: 1244 if (ipsec_enabled) { 1245 error = ipsec4_set_policy(inp, sopt->sopt_name, 1246 sopt->sopt_data, sopt->sopt_size, 1247 curlwp->l_cred); 1248 break; 1249 } 1250 /*FALLTHROUGH*/ 1251 #endif /* IPSEC */ 1252 1253 default: 1254 error = ENOPROTOOPT; 1255 break; 1256 } 1257 break; 1258 1259 case PRCO_GETOPT: 1260 switch (sopt->sopt_name) { 1261 case IP_OPTIONS: 1262 case IP_RETOPTS: { 1263 struct mbuf *mopts = inp->inp_options; 1264 1265 if (mopts) { 1266 struct mbuf *m; 1267 1268 m = m_copym(mopts, 0, M_COPYALL, M_DONTWAIT); 1269 if (m == NULL) { 1270 error = ENOBUFS; 1271 break; 1272 } 1273 error = sockopt_setmbuf(sopt, m); 1274 } 1275 break; 1276 } 1277 case IP_TOS: 1278 case IP_TTL: 1279 case IP_MINTTL: 1280 case IP_RECVOPTS: 1281 case IP_RECVRETOPTS: 1282 case IP_RECVDSTADDR: 1283 case IP_RECVIF: 1284 case IP_RECVPKTINFO: 1285 case IP_RECVTTL: 1286 case IP_ERRORMTU: 1287 switch (sopt->sopt_name) { 1288 case IP_TOS: 1289 optval = ip->ip_tos; 1290 break; 1291 1292 case IP_TTL: 1293 optval = ip->ip_ttl; 1294 break; 1295 1296 case IP_MINTTL: 1297 optval = inp->inp_ip_minttl; 1298 break; 1299 1300 case IP_ERRORMTU: 1301 optval = inp->inp_errormtu; 1302 break; 1303 1304 #define OPTBIT(bit) (inpflags & bit ? 1 : 0) 1305 1306 case IP_RECVOPTS: 1307 optval = OPTBIT(INP_RECVOPTS); 1308 break; 1309 1310 case IP_RECVPKTINFO: 1311 optval = OPTBIT(INP_RECVPKTINFO); 1312 break; 1313 1314 case IP_RECVRETOPTS: 1315 optval = OPTBIT(INP_RECVRETOPTS); 1316 break; 1317 1318 case IP_RECVDSTADDR: 1319 optval = OPTBIT(INP_RECVDSTADDR); 1320 break; 1321 1322 case IP_RECVIF: 1323 optval = OPTBIT(INP_RECVIF); 1324 break; 1325 1326 case IP_RECVTTL: 1327 optval = OPTBIT(INP_RECVTTL); 1328 break; 1329 } 1330 error = sockopt_setint(sopt, optval); 1331 break; 1332 1333 case IP_PKTINFO: 1334 switch (sopt->sopt_size) { 1335 case sizeof(int): 1336 /* Linux compatibility */ 1337 optval = OPTBIT(INP_RECVPKTINFO); 1338 error = sockopt_setint(sopt, optval); 1339 break; 1340 case sizeof(struct in_pktinfo): 1341 /* Solaris compatibility */ 1342 pktinfo.ipi_ifindex = 0; 1343 pktinfo.ipi_addr = inp->inp_prefsrcip; 1344 error = sockopt_set(sopt, &pktinfo, 1345 sizeof(pktinfo)); 1346 break; 1347 default: 1348 /* 1349 * While size is stuck at 0, and, later, if 1350 * the caller doesn't use an exactly sized 1351 * recipient for the data, default to Linux 1352 * compatibility 1353 */ 1354 optval = OPTBIT(INP_RECVPKTINFO); 1355 error = sockopt_setint(sopt, optval); 1356 break; 1357 } 1358 break; 1359 1360 #if 0 /* defined(IPSEC) */ 1361 case IP_IPSEC_POLICY: 1362 { 1363 struct mbuf *m = NULL; 1364 1365 /* XXX this will return EINVAL as sopt is empty */ 1366 error = ipsec4_get_policy(inp, sopt->sopt_data, 1367 sopt->sopt_size, &m); 1368 if (error == 0) 1369 error = sockopt_setmbuf(sopt, m); 1370 break; 1371 } 1372 #endif /*IPSEC*/ 1373 1374 case IP_MULTICAST_IF: 1375 case IP_MULTICAST_TTL: 1376 case IP_MULTICAST_LOOP: 1377 case IP_ADD_MEMBERSHIP: 1378 case IP_DROP_MEMBERSHIP: 1379 error = ip_getmoptions(inp->inp_moptions, sopt); 1380 break; 1381 1382 case IP_PORTRANGE: 1383 if (inpflags & INP_LOWPORT) 1384 optval = IP_PORTRANGE_LOW; 1385 else 1386 optval = IP_PORTRANGE_DEFAULT; 1387 error = sockopt_setint(sopt, optval); 1388 break; 1389 1390 case IP_PORTALGO: 1391 optval = inp->inp_portalgo; 1392 error = sockopt_setint(sopt, optval); 1393 break; 1394 1395 default: 1396 error = ENOPROTOOPT; 1397 break; 1398 } 1399 break; 1400 } 1401 1402 if (!error) { 1403 inp->inp_flags = inpflags; 1404 } 1405 return error; 1406 } 1407 1408 static int 1409 ip_pktinfo_prepare(const struct in_pktinfo *pktinfo, struct ip_pktopts *pktopts, 1410 int *flags, kauth_cred_t cred) 1411 { 1412 struct ip_moptions *imo; 1413 int error = 0; 1414 bool addrset = false; 1415 1416 if (!in_nullhost(pktinfo->ipi_addr)) { 1417 pktopts->ippo_laddr.sin_addr = pktinfo->ipi_addr; 1418 /* EADDRNOTAVAIL? */ 1419 error = in_pcbbindableaddr(&pktopts->ippo_laddr, cred); 1420 if (error != 0) 1421 return error; 1422 addrset = true; 1423 } 1424 1425 if (pktinfo->ipi_ifindex != 0) { 1426 if (!addrset) { 1427 struct ifnet *ifp; 1428 struct in_ifaddr *ia; 1429 int s; 1430 1431 /* pick up primary address */ 1432 s = pserialize_read_enter(); 1433 ifp = if_byindex(pktinfo->ipi_ifindex); 1434 if (ifp == NULL) { 1435 pserialize_read_exit(s); 1436 return EADDRNOTAVAIL; 1437 } 1438 ia = in_get_ia_from_ifp(ifp); 1439 if (ia == NULL) { 1440 pserialize_read_exit(s); 1441 return EADDRNOTAVAIL; 1442 } 1443 pktopts->ippo_laddr.sin_addr = IA_SIN(ia)->sin_addr; 1444 pserialize_read_exit(s); 1445 } 1446 1447 /* 1448 * If specified ipi_ifindex, 1449 * use copied or locally initialized ip_moptions. 1450 * Original ip_moptions must not be modified. 1451 */ 1452 imo = &pktopts->ippo_imobuf; /* local buf in pktopts */ 1453 if (pktopts->ippo_imo != NULL) { 1454 memcpy(imo, pktopts->ippo_imo, sizeof(*imo)); 1455 } else { 1456 memset(imo, 0, sizeof(*imo)); 1457 imo->imo_multicast_ttl = IP_DEFAULT_MULTICAST_TTL; 1458 imo->imo_multicast_loop = IP_DEFAULT_MULTICAST_LOOP; 1459 } 1460 imo->imo_multicast_if_index = pktinfo->ipi_ifindex; 1461 pktopts->ippo_imo = imo; 1462 *flags |= IP_ROUTETOIFINDEX; 1463 } 1464 return error; 1465 } 1466 1467 /* 1468 * Set up IP outgoing packet options. Even if control is NULL, 1469 * pktopts->ippo_laddr and pktopts->ippo_imo are set and used. 1470 */ 1471 int 1472 ip_setpktopts(struct mbuf *control, struct ip_pktopts *pktopts, int *flags, 1473 struct inpcb *inp, kauth_cred_t cred) 1474 { 1475 struct cmsghdr *cm; 1476 struct in_pktinfo pktinfo; 1477 int error; 1478 1479 pktopts->ippo_imo = inp->inp_moptions; 1480 1481 struct in_addr *ia = in_nullhost(inp->inp_prefsrcip) ? &inp->inp_laddr : 1482 &inp->inp_prefsrcip; 1483 sockaddr_in_init(&pktopts->ippo_laddr, ia, 0); 1484 1485 if (control == NULL) 1486 return 0; 1487 1488 /* 1489 * XXX: Currently, we assume all the optional information is 1490 * stored in a single mbuf. 1491 */ 1492 if (control->m_next) 1493 return EINVAL; 1494 1495 for (; control->m_len > 0; 1496 control->m_data += CMSG_ALIGN(cm->cmsg_len), 1497 control->m_len -= CMSG_ALIGN(cm->cmsg_len)) { 1498 cm = mtod(control, struct cmsghdr *); 1499 if ((control->m_len < sizeof(*cm)) || 1500 (cm->cmsg_len == 0) || 1501 (cm->cmsg_len > control->m_len)) { 1502 return EINVAL; 1503 } 1504 if (cm->cmsg_level != IPPROTO_IP) 1505 continue; 1506 1507 switch (cm->cmsg_type) { 1508 case IP_PKTINFO: 1509 if (cm->cmsg_len != CMSG_LEN(sizeof(pktinfo))) 1510 return EINVAL; 1511 memcpy(&pktinfo, CMSG_DATA(cm), sizeof(pktinfo)); 1512 error = ip_pktinfo_prepare(&pktinfo, pktopts, flags, 1513 cred); 1514 if (error) 1515 return error; 1516 break; 1517 case IP_SENDSRCADDR: /* FreeBSD compatibility */ 1518 if (cm->cmsg_len != CMSG_LEN(sizeof(struct in_addr))) 1519 return EINVAL; 1520 pktinfo.ipi_ifindex = 0; 1521 pktinfo.ipi_addr = 1522 ((struct in_pktinfo *)CMSG_DATA(cm))->ipi_addr; 1523 error = ip_pktinfo_prepare(&pktinfo, pktopts, flags, 1524 cred); 1525 if (error) 1526 return error; 1527 break; 1528 default: 1529 return ENOPROTOOPT; 1530 } 1531 } 1532 return 0; 1533 } 1534 1535 /* 1536 * Set up IP options in pcb for insertion in output packets. 1537 * Store in mbuf with pointer in pcbopt, adding pseudo-option 1538 * with destination address if source routed. 1539 */ 1540 static int 1541 ip_pcbopts(struct inpcb *inp, const struct sockopt *sopt) 1542 { 1543 struct mbuf *m; 1544 const u_char *cp; 1545 u_char *dp; 1546 int cnt; 1547 1548 KASSERT(inp_locked(inp)); 1549 1550 /* Turn off any old options. */ 1551 if (inp->inp_options) { 1552 m_free(inp->inp_options); 1553 } 1554 inp->inp_options = NULL; 1555 if ((cnt = sopt->sopt_size) == 0) { 1556 /* Only turning off any previous options. */ 1557 return 0; 1558 } 1559 cp = sopt->sopt_data; 1560 1561 #ifndef __vax__ 1562 if (cnt % sizeof(int32_t)) 1563 return (EINVAL); 1564 #endif 1565 1566 m = m_get(M_DONTWAIT, MT_SOOPTS); 1567 if (m == NULL) 1568 return (ENOBUFS); 1569 1570 dp = mtod(m, u_char *); 1571 memset(dp, 0, sizeof(struct in_addr)); 1572 dp += sizeof(struct in_addr); 1573 m->m_len = sizeof(struct in_addr); 1574 1575 /* 1576 * IP option list according to RFC791. Each option is of the form 1577 * 1578 * [optval] [olen] [(olen - 2) data bytes] 1579 * 1580 * We validate the list and copy options to an mbuf for prepending 1581 * to data packets. The IP first-hop destination address will be 1582 * stored before actual options and is zero if unset. 1583 */ 1584 while (cnt > 0) { 1585 uint8_t optval, olen, offset; 1586 1587 optval = cp[IPOPT_OPTVAL]; 1588 1589 if (optval == IPOPT_EOL || optval == IPOPT_NOP) { 1590 olen = 1; 1591 } else { 1592 if (cnt < IPOPT_OLEN + 1) 1593 goto bad; 1594 1595 olen = cp[IPOPT_OLEN]; 1596 if (olen < IPOPT_OLEN + 1 || olen > cnt) 1597 goto bad; 1598 } 1599 1600 if (optval == IPOPT_LSRR || optval == IPOPT_SSRR) { 1601 /* 1602 * user process specifies route as: 1603 * ->A->B->C->D 1604 * D must be our final destination (but we can't 1605 * check that since we may not have connected yet). 1606 * A is first hop destination, which doesn't appear in 1607 * actual IP option, but is stored before the options. 1608 */ 1609 if (olen < IPOPT_OFFSET + 1 + sizeof(struct in_addr)) 1610 goto bad; 1611 1612 offset = cp[IPOPT_OFFSET]; 1613 memcpy(mtod(m, u_char *), cp + IPOPT_OFFSET + 1, 1614 sizeof(struct in_addr)); 1615 1616 cp += sizeof(struct in_addr); 1617 cnt -= sizeof(struct in_addr); 1618 olen -= sizeof(struct in_addr); 1619 1620 if (m->m_len + olen > MAX_IPOPTLEN + sizeof(struct in_addr)) 1621 goto bad; 1622 1623 memcpy(dp, cp, olen); 1624 dp[IPOPT_OPTVAL] = optval; 1625 dp[IPOPT_OLEN] = olen; 1626 dp[IPOPT_OFFSET] = offset; 1627 break; 1628 } else { 1629 if (m->m_len + olen > MAX_IPOPTLEN + sizeof(struct in_addr)) 1630 goto bad; 1631 1632 memcpy(dp, cp, olen); 1633 break; 1634 } 1635 1636 dp += olen; 1637 m->m_len += olen; 1638 1639 if (optval == IPOPT_EOL) 1640 break; 1641 1642 cp += olen; 1643 cnt -= olen; 1644 } 1645 1646 inp->inp_options = m; 1647 return 0; 1648 bad: 1649 (void)m_free(m); 1650 return EINVAL; 1651 } 1652 1653 /* 1654 * following RFC1724 section 3.3, 0.0.0.0/8 is interpreted as interface index. 1655 * Must be called in a pserialize critical section. 1656 */ 1657 static struct ifnet * 1658 ip_multicast_if(struct in_addr *a, int *ifindexp) 1659 { 1660 int ifindex; 1661 struct ifnet *ifp = NULL; 1662 struct in_ifaddr *ia; 1663 1664 if (ifindexp) 1665 *ifindexp = 0; 1666 if (ntohl(a->s_addr) >> 24 == 0) { 1667 ifindex = ntohl(a->s_addr) & 0xffffff; 1668 ifp = if_byindex(ifindex); 1669 if (!ifp) 1670 return NULL; 1671 if (ifindexp) 1672 *ifindexp = ifindex; 1673 } else { 1674 IN_ADDRHASH_READER_FOREACH(ia, a->s_addr) { 1675 if (in_hosteq(ia->ia_addr.sin_addr, *a) && 1676 (ia->ia_ifp->if_flags & IFF_MULTICAST) != 0) { 1677 ifp = ia->ia_ifp; 1678 if (if_is_deactivated(ifp)) 1679 ifp = NULL; 1680 break; 1681 } 1682 } 1683 } 1684 return ifp; 1685 } 1686 1687 static int 1688 ip_getoptval(const struct sockopt *sopt, u_int8_t *val, u_int maxval) 1689 { 1690 u_int tval; 1691 u_char cval; 1692 int error; 1693 1694 if (sopt == NULL) 1695 return EINVAL; 1696 1697 switch (sopt->sopt_size) { 1698 case sizeof(u_char): 1699 error = sockopt_get(sopt, &cval, sizeof(u_char)); 1700 tval = cval; 1701 break; 1702 1703 case sizeof(u_int): 1704 error = sockopt_get(sopt, &tval, sizeof(u_int)); 1705 break; 1706 1707 default: 1708 error = EINVAL; 1709 } 1710 1711 if (error) 1712 return error; 1713 1714 if (tval > maxval) 1715 return EINVAL; 1716 1717 *val = tval; 1718 return 0; 1719 } 1720 1721 static int 1722 ip_get_membership(const struct sockopt *sopt, struct ifnet **ifp, 1723 struct psref *psref, struct in_addr *ia, bool add) 1724 { 1725 int error; 1726 struct ip_mreq mreq; 1727 1728 error = sockopt_get(sopt, &mreq, sizeof(mreq)); 1729 if (error) 1730 return error; 1731 1732 if (!IN_MULTICAST(mreq.imr_multiaddr.s_addr)) 1733 return EINVAL; 1734 1735 memcpy(ia, &mreq.imr_multiaddr, sizeof(*ia)); 1736 1737 if (in_nullhost(mreq.imr_interface)) { 1738 union { 1739 struct sockaddr dst; 1740 struct sockaddr_in dst4; 1741 } u; 1742 struct route ro; 1743 1744 if (!add) { 1745 *ifp = NULL; 1746 return 0; 1747 } 1748 /* 1749 * If no interface address was provided, use the interface of 1750 * the route to the given multicast address. 1751 */ 1752 struct rtentry *rt; 1753 memset(&ro, 0, sizeof(ro)); 1754 1755 sockaddr_in_init(&u.dst4, ia, 0); 1756 error = rtcache_setdst(&ro, &u.dst); 1757 if (error != 0) 1758 return error; 1759 *ifp = (rt = rtcache_init(&ro)) != NULL ? rt->rt_ifp : NULL; 1760 if (*ifp != NULL) { 1761 if (if_is_deactivated(*ifp)) 1762 *ifp = NULL; 1763 else 1764 if_acquire(*ifp, psref); 1765 } 1766 rtcache_unref(rt, &ro); 1767 rtcache_free(&ro); 1768 } else { 1769 int s = pserialize_read_enter(); 1770 *ifp = ip_multicast_if(&mreq.imr_interface, NULL); 1771 if (!add && *ifp == NULL) { 1772 pserialize_read_exit(s); 1773 return EADDRNOTAVAIL; 1774 } 1775 if (*ifp != NULL) { 1776 if (if_is_deactivated(*ifp)) 1777 *ifp = NULL; 1778 else 1779 if_acquire(*ifp, psref); 1780 } 1781 pserialize_read_exit(s); 1782 } 1783 return 0; 1784 } 1785 1786 /* 1787 * Add a multicast group membership. 1788 * Group must be a valid IP multicast address. 1789 */ 1790 static int 1791 ip_add_membership(struct ip_moptions *imo, const struct sockopt *sopt) 1792 { 1793 struct ifnet *ifp = NULL; // XXX: gcc [ppc] 1794 struct in_addr ia; 1795 int i, error, bound; 1796 struct psref psref; 1797 1798 /* imo is protected by solock or referenced only by the caller */ 1799 1800 bound = curlwp_bind(); 1801 if (sopt->sopt_size == sizeof(struct ip_mreq)) 1802 error = ip_get_membership(sopt, &ifp, &psref, &ia, true); 1803 else 1804 #ifdef INET6 1805 error = ip6_get_membership(sopt, &ifp, &psref, &ia, sizeof(ia)); 1806 #else 1807 error = EINVAL; 1808 goto out; 1809 #endif 1810 1811 if (error) 1812 goto out; 1813 1814 /* 1815 * See if we found an interface, and confirm that it 1816 * supports multicast. 1817 */ 1818 if (ifp == NULL || (ifp->if_flags & IFF_MULTICAST) == 0) { 1819 error = EADDRNOTAVAIL; 1820 goto out; 1821 } 1822 1823 /* 1824 * See if the membership already exists or if all the 1825 * membership slots are full. 1826 */ 1827 for (i = 0; i < imo->imo_num_memberships; ++i) { 1828 if (imo->imo_membership[i]->inm_ifp == ifp && 1829 in_hosteq(imo->imo_membership[i]->inm_addr, ia)) 1830 break; 1831 } 1832 if (i < imo->imo_num_memberships) { 1833 error = EADDRINUSE; 1834 goto out; 1835 } 1836 1837 if (i == IP_MAX_MEMBERSHIPS) { 1838 error = ETOOMANYREFS; 1839 goto out; 1840 } 1841 1842 /* 1843 * Everything looks good; add a new record to the multicast 1844 * address list for the given interface. 1845 */ 1846 IFNET_LOCK(ifp); 1847 imo->imo_membership[i] = in_addmulti(&ia, ifp); 1848 IFNET_UNLOCK(ifp); 1849 if (imo->imo_membership[i] == NULL) { 1850 error = ENOBUFS; 1851 goto out; 1852 } 1853 1854 ++imo->imo_num_memberships; 1855 error = 0; 1856 out: 1857 if_put(ifp, &psref); 1858 curlwp_bindx(bound); 1859 return error; 1860 } 1861 1862 /* 1863 * Drop a multicast group membership. 1864 * Group must be a valid IP multicast address. 1865 */ 1866 static int 1867 ip_drop_membership(struct ip_moptions *imo, const struct sockopt *sopt) 1868 { 1869 struct in_addr ia = { .s_addr = 0 }; // XXX: gcc [ppc] 1870 struct ifnet *ifp = NULL; // XXX: gcc [ppc] 1871 int i, error, bound; 1872 struct psref psref; 1873 1874 /* imo is protected by solock or referenced only by the caller */ 1875 1876 bound = curlwp_bind(); 1877 if (sopt->sopt_size == sizeof(struct ip_mreq)) 1878 error = ip_get_membership(sopt, &ifp, &psref, &ia, false); 1879 else { 1880 #ifdef INET6 1881 error = ip6_get_membership(sopt, &ifp, &psref, &ia, sizeof(ia)); 1882 #else 1883 error = EINVAL; 1884 goto out; 1885 #endif 1886 } 1887 1888 if (error) 1889 goto out; 1890 1891 /* 1892 * Find the membership in the membership array. 1893 */ 1894 for (i = 0; i < imo->imo_num_memberships; ++i) { 1895 if ((ifp == NULL || 1896 imo->imo_membership[i]->inm_ifp == ifp) && 1897 in_hosteq(imo->imo_membership[i]->inm_addr, ia)) 1898 break; 1899 } 1900 if (i == imo->imo_num_memberships) { 1901 error = EADDRNOTAVAIL; 1902 goto out; 1903 } 1904 1905 /* 1906 * Give up the multicast address record to which the 1907 * membership points. 1908 */ 1909 if (ifp) 1910 IFNET_LOCK(ifp); 1911 in_delmulti(imo->imo_membership[i]); 1912 if (ifp) 1913 IFNET_UNLOCK(ifp); 1914 1915 /* 1916 * Remove the gap in the membership array. 1917 */ 1918 for (++i; i < imo->imo_num_memberships; ++i) 1919 imo->imo_membership[i-1] = imo->imo_membership[i]; 1920 --imo->imo_num_memberships; 1921 error = 0; 1922 out: 1923 if_put(ifp, &psref); 1924 curlwp_bindx(bound); 1925 return error; 1926 } 1927 1928 /* 1929 * Set the IP multicast options in response to user setsockopt(). 1930 */ 1931 int 1932 ip_setmoptions(struct ip_moptions **pimo, const struct sockopt *sopt) 1933 { 1934 struct ip_moptions *imo = *pimo; 1935 struct in_addr addr; 1936 struct ifnet *ifp; 1937 int ifindex, error = 0; 1938 1939 /* The passed imo isn't NULL, it should be protected by solock */ 1940 1941 if (!imo) { 1942 /* 1943 * No multicast option buffer attached to the pcb; 1944 * allocate one and initialize to default values. 1945 */ 1946 imo = kmem_intr_alloc(sizeof(*imo), KM_NOSLEEP); 1947 if (imo == NULL) 1948 return ENOBUFS; 1949 1950 imo->imo_multicast_if_index = 0; 1951 imo->imo_multicast_addr.s_addr = INADDR_ANY; 1952 imo->imo_multicast_ttl = IP_DEFAULT_MULTICAST_TTL; 1953 imo->imo_multicast_loop = IP_DEFAULT_MULTICAST_LOOP; 1954 imo->imo_num_memberships = 0; 1955 *pimo = imo; 1956 } 1957 1958 switch (sopt->sopt_name) { 1959 case IP_MULTICAST_IF: { 1960 int s; 1961 /* 1962 * Select the interface for outgoing multicast packets. 1963 */ 1964 error = sockopt_get(sopt, &addr, sizeof(addr)); 1965 if (error) 1966 break; 1967 1968 /* 1969 * INADDR_ANY is used to remove a previous selection. 1970 * When no interface is selected, a default one is 1971 * chosen every time a multicast packet is sent. 1972 */ 1973 if (in_nullhost(addr)) { 1974 imo->imo_multicast_if_index = 0; 1975 break; 1976 } 1977 /* 1978 * The selected interface is identified by its local 1979 * IP address. Find the interface and confirm that 1980 * it supports multicasting. 1981 */ 1982 s = pserialize_read_enter(); 1983 ifp = ip_multicast_if(&addr, &ifindex); 1984 if (ifp == NULL || (ifp->if_flags & IFF_MULTICAST) == 0) { 1985 pserialize_read_exit(s); 1986 error = EADDRNOTAVAIL; 1987 break; 1988 } 1989 imo->imo_multicast_if_index = ifp->if_index; 1990 pserialize_read_exit(s); 1991 if (ifindex) 1992 imo->imo_multicast_addr = addr; 1993 else 1994 imo->imo_multicast_addr.s_addr = INADDR_ANY; 1995 break; 1996 } 1997 1998 case IP_MULTICAST_TTL: 1999 /* 2000 * Set the IP time-to-live for outgoing multicast packets. 2001 */ 2002 error = ip_getoptval(sopt, &imo->imo_multicast_ttl, MAXTTL); 2003 break; 2004 2005 case IP_MULTICAST_LOOP: 2006 /* 2007 * Set the loopback flag for outgoing multicast packets. 2008 * Must be zero or one. 2009 */ 2010 error = ip_getoptval(sopt, &imo->imo_multicast_loop, 1); 2011 break; 2012 2013 case IP_ADD_MEMBERSHIP: /* IPV6_JOIN_GROUP */ 2014 error = ip_add_membership(imo, sopt); 2015 break; 2016 2017 case IP_DROP_MEMBERSHIP: /* IPV6_LEAVE_GROUP */ 2018 error = ip_drop_membership(imo, sopt); 2019 break; 2020 2021 default: 2022 error = EOPNOTSUPP; 2023 break; 2024 } 2025 2026 /* 2027 * If all options have default values, no need to keep the mbuf. 2028 */ 2029 if (imo->imo_multicast_if_index == 0 && 2030 imo->imo_multicast_ttl == IP_DEFAULT_MULTICAST_TTL && 2031 imo->imo_multicast_loop == IP_DEFAULT_MULTICAST_LOOP && 2032 imo->imo_num_memberships == 0) { 2033 kmem_intr_free(imo, sizeof(*imo)); 2034 *pimo = NULL; 2035 } 2036 2037 return error; 2038 } 2039 2040 /* 2041 * Return the IP multicast options in response to user getsockopt(). 2042 */ 2043 int 2044 ip_getmoptions(struct ip_moptions *imo, struct sockopt *sopt) 2045 { 2046 struct in_addr addr; 2047 uint8_t optval; 2048 int error = 0; 2049 2050 /* imo is protected by solock or refereced only by the caller */ 2051 2052 switch (sopt->sopt_name) { 2053 case IP_MULTICAST_IF: 2054 if (imo == NULL || imo->imo_multicast_if_index == 0) 2055 addr = zeroin_addr; 2056 else if (imo->imo_multicast_addr.s_addr) { 2057 /* return the value user has set */ 2058 addr = imo->imo_multicast_addr; 2059 } else { 2060 struct ifnet *ifp; 2061 struct in_ifaddr *ia = NULL; 2062 int s = pserialize_read_enter(); 2063 2064 ifp = if_byindex(imo->imo_multicast_if_index); 2065 if (ifp != NULL) { 2066 ia = in_get_ia_from_ifp(ifp); 2067 } 2068 addr = ia ? ia->ia_addr.sin_addr : zeroin_addr; 2069 pserialize_read_exit(s); 2070 } 2071 error = sockopt_set(sopt, &addr, sizeof(addr)); 2072 break; 2073 2074 case IP_MULTICAST_TTL: 2075 optval = imo ? imo->imo_multicast_ttl 2076 : IP_DEFAULT_MULTICAST_TTL; 2077 2078 error = sockopt_set(sopt, &optval, sizeof(optval)); 2079 break; 2080 2081 case IP_MULTICAST_LOOP: 2082 optval = imo ? imo->imo_multicast_loop 2083 : IP_DEFAULT_MULTICAST_LOOP; 2084 2085 error = sockopt_set(sopt, &optval, sizeof(optval)); 2086 break; 2087 2088 default: 2089 error = EOPNOTSUPP; 2090 } 2091 2092 return error; 2093 } 2094 2095 /* 2096 * Discard the IP multicast options. 2097 */ 2098 void 2099 ip_freemoptions(struct ip_moptions *imo) 2100 { 2101 int i; 2102 2103 /* The owner of imo (inp) should be protected by solock */ 2104 2105 if (imo != NULL) { 2106 for (i = 0; i < imo->imo_num_memberships; ++i) { 2107 struct in_multi *inm = imo->imo_membership[i]; 2108 struct ifnet *ifp = inm->inm_ifp; 2109 IFNET_LOCK(ifp); 2110 in_delmulti(inm); 2111 /* ifp should not leave thanks to solock */ 2112 IFNET_UNLOCK(ifp); 2113 } 2114 2115 kmem_intr_free(imo, sizeof(*imo)); 2116 } 2117 } 2118 2119 /* 2120 * Routine called from ip_output() to loop back a copy of an IP multicast 2121 * packet to the input queue of a specified interface. Note that this 2122 * calls the output routine of the loopback "driver", but with an interface 2123 * pointer that might NOT be lo0ifp -- easier than replicating that code here. 2124 */ 2125 static void 2126 ip_mloopback(struct ifnet *ifp, struct mbuf *m, const struct sockaddr_in *dst) 2127 { 2128 struct ip *ip; 2129 struct mbuf *copym; 2130 2131 copym = m_copypacket(m, M_DONTWAIT); 2132 if (copym != NULL && 2133 (copym->m_flags & M_EXT || copym->m_len < sizeof(struct ip))) 2134 copym = m_pullup(copym, sizeof(struct ip)); 2135 if (copym == NULL) 2136 return; 2137 /* 2138 * We don't bother to fragment if the IP length is greater 2139 * than the interface's MTU. Can this possibly matter? 2140 */ 2141 ip = mtod(copym, struct ip *); 2142 2143 if (copym->m_pkthdr.csum_flags & (M_CSUM_TCPv4|M_CSUM_UDPv4)) { 2144 in_delayed_cksum(copym); 2145 copym->m_pkthdr.csum_flags &= 2146 ~(M_CSUM_TCPv4|M_CSUM_UDPv4); 2147 } 2148 2149 ip->ip_sum = 0; 2150 ip->ip_sum = in_cksum(copym, ip->ip_hl << 2); 2151 KERNEL_LOCK_UNLESS_NET_MPSAFE(); 2152 (void)looutput(ifp, copym, sintocsa(dst), NULL); 2153 KERNEL_UNLOCK_UNLESS_NET_MPSAFE(); 2154 } 2155 2156 /* 2157 * Ensure sending address is valid. 2158 * Returns 0 on success, -1 if an error should be sent back or 1 2159 * if the packet could be dropped without error (protocol dependent). 2160 */ 2161 static int 2162 ip_ifaddrvalid(const struct in_ifaddr *ia) 2163 { 2164 2165 if (ia->ia_addr.sin_addr.s_addr == INADDR_ANY) 2166 return 0; 2167 2168 if (ia->ia4_flags & IN_IFF_DUPLICATED) 2169 return -1; 2170 else if (ia->ia4_flags & (IN_IFF_TENTATIVE | IN_IFF_DETACHED)) 2171 return 1; 2172 2173 return 0; 2174 } 2175
Indexes created Wed Sep 24 05:09:52 GMT 2025