ip_output.c revision 1.324.2.2
1 /* $NetBSD: ip_output.c,v 1.324.2.2 2024/09/21 12:28:46 martin Exp $ */ 2 3 /* 4 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the project nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 /* 33 * Copyright (c) 1998 The NetBSD Foundation, Inc. 34 * All rights reserved. 35 * 36 * This code is derived from software contributed to The NetBSD Foundation 37 * by Public Access Networks Corporation ("Panix"). It was developed under 38 * contract to Panix by Eric Haszlakiewicz and Thor Lancelot Simon. 39 * 40 * Redistribution and use in source and binary forms, with or without 41 * modification, are permitted provided that the following conditions 42 * are met: 43 * 1. Redistributions of source code must retain the above copyright 44 * notice, this list of conditions and the following disclaimer. 45 * 2. Redistributions in binary form must reproduce the above copyright 46 * notice, this list of conditions and the following disclaimer in the 47 * documentation and/or other materials provided with the distribution. 48 * 49 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 50 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 51 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 52 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 53 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 54 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 55 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 56 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 57 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 58 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 59 * POSSIBILITY OF SUCH DAMAGE. 60 */ 61 62 /* 63 * Copyright (c) 1982, 1986, 1988, 1990, 1993 64 * The Regents of the University of California. All rights reserved. 65 * 66 * Redistribution and use in source and binary forms, with or without 67 * modification, are permitted provided that the following conditions 68 * are met: 69 * 1. Redistributions of source code must retain the above copyright 70 * notice, this list of conditions and the following disclaimer. 71 * 2. Redistributions in binary form must reproduce the above copyright 72 * notice, this list of conditions and the following disclaimer in the 73 * documentation and/or other materials provided with the distribution. 74 * 3. Neither the name of the University nor the names of its contributors 75 * may be used to endorse or promote products derived from this software 76 * without specific prior written permission. 77 * 78 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 79 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 80 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 81 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 82 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 83 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 84 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 85 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 86 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 87 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 88 * SUCH DAMAGE. 89 * 90 * @(#)ip_output.c 8.3 (Berkeley) 1/21/94 91 */ 92 93 #include <sys/cdefs.h> 94 __KERNEL_RCSID(0, "$NetBSD: ip_output.c,v 1.324.2.2 2024/09/21 12:28:46 martin Exp $"); 95 96 #ifdef _KERNEL_OPT 97 #include "opt_inet.h" 98 #include "opt_ipsec.h" 99 #include "opt_mrouting.h" 100 #include "opt_net_mpsafe.h" 101 #include "opt_mpls.h" 102 #endif 103 104 #include "arp.h" 105 106 #include <sys/param.h> 107 #include <sys/kmem.h> 108 #include <sys/mbuf.h> 109 #include <sys/socket.h> 110 #include <sys/socketvar.h> 111 #include <sys/kauth.h> 112 #include <sys/systm.h> 113 #include <sys/syslog.h> 114 115 #include <net/if.h> 116 #include <net/if_types.h> 117 #include <net/route.h> 118 #include <net/pfil.h> 119 120 #include <netinet/in.h> 121 #include <netinet/in_systm.h> 122 #include <netinet/ip.h> 123 #include <netinet/in_pcb.h> 124 #include <netinet/in_var.h> 125 #include <netinet/ip_var.h> 126 #include <netinet/ip_private.h> 127 #include <netinet/in_offload.h> 128 #include <netinet/portalgo.h> 129 #include <netinet/udp.h> 130 #include <netinet/udp_var.h> 131 132 #ifdef INET6 133 #include <netinet6/ip6_var.h> 134 #endif 135 136 #ifdef MROUTING 137 #include <netinet/ip_mroute.h> 138 #endif 139 140 #ifdef IPSEC 141 #include <netipsec/ipsec.h> 142 #include <netipsec/key.h> 143 #endif 144 145 #ifdef MPLS 146 #include <netmpls/mpls.h> 147 #include <netmpls/mpls_var.h> 148 #endif 149 150 static int ip_pcbopts(struct inpcb *, const struct sockopt *); 151 static struct mbuf *ip_insertoptions(struct mbuf *, struct mbuf *, int *); 152 static struct ifnet *ip_multicast_if(struct in_addr *, int *); 153 static void ip_mloopback(struct ifnet *, struct mbuf *, 154 const struct sockaddr_in *); 155 static int ip_ifaddrvalid(const struct in_ifaddr *); 156 157 extern pfil_head_t *inet_pfil_hook; /* XXX */ 158 159 int ip_do_loopback_cksum = 0; 160 161 static int 162 ip_mark_mpls(struct ifnet * const ifp, struct mbuf * const m, 163 const struct rtentry *rt) 164 { 165 int error = 0; 166 #ifdef MPLS 167 union mpls_shim msh; 168 169 if (rt == NULL || rt_gettag(rt) == NULL || 170 rt_gettag(rt)->sa_family != AF_MPLS || 171 (m->m_flags & (M_MCAST | M_BCAST)) != 0 || 172 ifp->if_type != IFT_ETHER) 173 return 0; 174 175 msh.s_addr = MPLS_GETSADDR(rt); 176 if (msh.shim.label != MPLS_LABEL_IMPLNULL) { 177 struct m_tag *mtag; 178 /* 179 * XXX tentative solution to tell ether_output 180 * it's MPLS. Need some more efficient solution. 181 */ 182 mtag = m_tag_get(PACKET_TAG_MPLS, 183 sizeof(int) /* dummy */, 184 M_NOWAIT); 185 if (mtag == NULL) 186 return ENOMEM; 187 m_tag_prepend(m, mtag); 188 } 189 #endif 190 return error; 191 } 192 193 /* 194 * Send an IP packet to a host. 195 */ 196 int 197 ip_if_output(struct ifnet * const ifp, struct mbuf * const m, 198 const struct sockaddr * const dst, const struct rtentry *rt) 199 { 200 int error = 0; 201 202 if (rt != NULL) { 203 error = rt_check_reject_route(rt, ifp); 204 if (error != 0) { 205 IP_STATINC(IP_STAT_RTREJECT); 206 m_freem(m); 207 return error; 208 } 209 } 210 211 error = ip_mark_mpls(ifp, m, rt); 212 if (error != 0) { 213 m_freem(m); 214 return error; 215 } 216 217 error = if_output_lock(ifp, ifp, m, dst, rt); 218 219 return error; 220 } 221 222 /* 223 * IP output. The packet in mbuf chain m contains a skeletal IP 224 * header (with len, off, ttl, proto, tos, src, dst). 225 * The mbuf chain containing the packet will be freed. 226 * The mbuf opt, if present, will not be freed. 227 */ 228 int 229 ip_output(struct mbuf *m0, struct mbuf *opt, struct route *ro, int flags, 230 struct ip_moptions *imo, struct inpcb *inp) 231 { 232 struct rtentry *rt; 233 struct ip *ip; 234 struct ifnet *ifp, *mifp = NULL; 235 struct mbuf *m = m0; 236 int len, hlen, error = 0; 237 struct route iproute; 238 const struct sockaddr_in *dst; 239 struct in_ifaddr *ia = NULL; 240 struct ifaddr *ifa; 241 int isbroadcast; 242 int sw_csum; 243 u_long mtu; 244 bool natt_frag = false; 245 bool rtmtu_nolock; 246 union { 247 struct sockaddr sa; 248 struct sockaddr_in sin; 249 } udst, usrc; 250 struct sockaddr *rdst = &udst.sa; /* real IP destination, as 251 * opposed to the nexthop 252 */ 253 struct psref psref, psref_ia; 254 int bound; 255 bool bind_need_restore = false; 256 const struct sockaddr *sa; 257 258 len = 0; 259 260 MCLAIM(m, &ip_tx_mowner); 261 262 KASSERT((m->m_flags & M_PKTHDR) != 0); 263 KASSERT((m->m_pkthdr.csum_flags & (M_CSUM_TCPv6|M_CSUM_UDPv6)) == 0); 264 KASSERT((m->m_pkthdr.csum_flags & (M_CSUM_TCPv4|M_CSUM_UDPv4)) != 265 (M_CSUM_TCPv4|M_CSUM_UDPv4)); 266 KASSERT(m->m_len >= sizeof(struct ip)); 267 268 hlen = sizeof(struct ip); 269 if (opt) { 270 m = ip_insertoptions(m, opt, &len); 271 hlen = len; 272 } 273 ip = mtod(m, struct ip *); 274 275 /* 276 * Fill in IP header. 277 */ 278 if ((flags & (IP_FORWARDING|IP_RAWOUTPUT)) == 0) { 279 ip->ip_v = IPVERSION; 280 ip->ip_off = htons(0); 281 /* ip->ip_id filled in after we find out source ia */ 282 ip->ip_hl = hlen >> 2; 283 IP_STATINC(IP_STAT_LOCALOUT); 284 } else { 285 hlen = ip->ip_hl << 2; 286 } 287 288 /* 289 * Route packet. 290 */ 291 if (ro == NULL) { 292 memset(&iproute, 0, sizeof(iproute)); 293 ro = &iproute; 294 } 295 sockaddr_in_init(&udst.sin, &ip->ip_dst, 0); 296 dst = satocsin(rtcache_getdst(ro)); 297 298 /* 299 * If there is a cached route, check that it is to the same 300 * destination and is still up. If not, free it and try again. 301 * The address family should also be checked in case of sharing 302 * the cache with IPv6. 303 */ 304 if (dst && (dst->sin_family != AF_INET || 305 !in_hosteq(dst->sin_addr, ip->ip_dst))) 306 rtcache_free(ro); 307 308 /* XXX must be before rtcache operations */ 309 bound = curlwp_bind(); 310 bind_need_restore = true; 311 312 if ((rt = rtcache_validate(ro)) == NULL && 313 (rt = rtcache_update(ro, 1)) == NULL) { 314 dst = &udst.sin; 315 error = rtcache_setdst(ro, &udst.sa); 316 if (error != 0) { 317 IP_STATINC(IP_STAT_ODROPPED); 318 goto bad; 319 } 320 } 321 322 /* 323 * If routing to interface only, short circuit routing lookup. 324 */ 325 if (flags & IP_ROUTETOIF) { 326 ifa = ifa_ifwithladdr_psref(sintocsa(dst), &psref_ia); 327 if (ifa == NULL) { 328 IP_STATINC(IP_STAT_NOROUTE); 329 error = ENETUNREACH; 330 goto bad; 331 } 332 /* ia is already referenced by psref_ia */ 333 ia = ifatoia(ifa); 334 335 ifp = ia->ia_ifp; 336 mtu = ifp->if_mtu; 337 ip->ip_ttl = 1; 338 isbroadcast = in_broadcast(dst->sin_addr, ifp); 339 } else if (((IN_MULTICAST(ip->ip_dst.s_addr) || 340 ip->ip_dst.s_addr == INADDR_BROADCAST) || 341 (flags & IP_ROUTETOIFINDEX)) && 342 imo != NULL && imo->imo_multicast_if_index != 0) { 343 ifp = mifp = if_get_byindex(imo->imo_multicast_if_index, &psref); 344 if (ifp == NULL) { 345 IP_STATINC(IP_STAT_NOROUTE); 346 error = ENETUNREACH; 347 goto bad; 348 } 349 mtu = ifp->if_mtu; 350 ia = in_get_ia_from_ifp_psref(ifp, &psref_ia); 351 if (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 IP_STATINC(IP_STAT_IFNOADDR); 454 error = EADDRNOTAVAIL; 455 goto bad; 456 } 457 xifa = &xia->ia_ifa; 458 if (xifa->ifa_getifa != NULL) { 459 ia4_release(xia, &_psref); 460 /* FIXME ifa_getifa is NOMPSAFE */ 461 xia = ifatoia((*xifa->ifa_getifa)(xifa, rdst)); 462 if (xia == NULL) { 463 IP_STATINC(IP_STAT_IFNOADDR); 464 error = EADDRNOTAVAIL; 465 goto bad; 466 } 467 ia4_acquire(xia, &_psref); 468 } 469 ip->ip_src = xia->ia_addr.sin_addr; 470 ia4_release(xia, &_psref); 471 } 472 473 inmgroup = in_multi_group(ip->ip_dst, ifp, flags); 474 if (inmgroup && (imo == NULL || imo->imo_multicast_loop)) { 475 /* 476 * If we belong to the destination multicast group 477 * on the outgoing interface, and the caller did not 478 * forbid loopback, loop back a copy. 479 */ 480 ip_mloopback(ifp, m, &udst.sin); 481 } 482 #ifdef MROUTING 483 else { 484 /* 485 * If we are acting as a multicast router, perform 486 * multicast forwarding as if the packet had just 487 * arrived on the interface to which we are about 488 * to send. The multicast forwarding function 489 * recursively calls this function, using the 490 * IP_FORWARDING flag to prevent infinite recursion. 491 * 492 * Multicasts that are looped back by ip_mloopback(), 493 * above, will be forwarded by the ip_input() routine, 494 * if necessary. 495 */ 496 extern struct socket *ip_mrouter; 497 498 if (ip_mrouter && (flags & IP_FORWARDING) == 0) { 499 if (ip_mforward(m, ifp) != 0) { 500 m_freem(m); 501 goto done; 502 } 503 } 504 } 505 #endif 506 /* 507 * Multicasts with a time-to-live of zero may be looped- 508 * back, above, but must not be transmitted on a network. 509 * Also, multicasts addressed to the loopback interface 510 * are not sent -- the above call to ip_mloopback() will 511 * loop back a copy if this host actually belongs to the 512 * destination group on the loopback interface. 513 */ 514 if (ip->ip_ttl == 0 || (ifp->if_flags & IFF_LOOPBACK) != 0) { 515 IP_STATINC(IP_STAT_ODROPPED); 516 m_freem(m); 517 goto done; 518 } 519 goto sendit; 520 } 521 522 /* 523 * If source address not specified yet, use address 524 * of outgoing interface. 525 */ 526 if (in_nullhost(ip->ip_src)) { 527 struct ifaddr *xifa; 528 529 xifa = &ia->ia_ifa; 530 if (xifa->ifa_getifa != NULL) { 531 ia4_release(ia, &psref_ia); 532 /* FIXME ifa_getifa is NOMPSAFE */ 533 ia = ifatoia((*xifa->ifa_getifa)(xifa, rdst)); 534 if (ia == NULL) { 535 error = EADDRNOTAVAIL; 536 goto bad; 537 } 538 ia4_acquire(ia, &psref_ia); 539 } 540 ip->ip_src = ia->ia_addr.sin_addr; 541 } 542 543 /* 544 * Packets with Class-D address as source are not valid per 545 * RFC1112. 546 */ 547 if (IN_MULTICAST(ip->ip_src.s_addr)) { 548 IP_STATINC(IP_STAT_ODROPPED); 549 error = EADDRNOTAVAIL; 550 goto bad; 551 } 552 553 /* 554 * Look for broadcast address and verify user is allowed to 555 * send such a packet. 556 */ 557 if (isbroadcast) { 558 if ((ifp->if_flags & IFF_BROADCAST) == 0) { 559 IP_STATINC(IP_STAT_BCASTDENIED); 560 error = EADDRNOTAVAIL; 561 goto bad; 562 } 563 if ((flags & IP_ALLOWBROADCAST) == 0) { 564 IP_STATINC(IP_STAT_BCASTDENIED); 565 error = EACCES; 566 goto bad; 567 } 568 /* don't allow broadcast messages to be fragmented */ 569 if (ntohs(ip->ip_len) > ifp->if_mtu) { 570 IP_STATINC(IP_STAT_BCASTDENIED); 571 error = EMSGSIZE; 572 goto bad; 573 } 574 m->m_flags |= M_BCAST; 575 } else 576 m->m_flags &= ~M_BCAST; 577 578 sendit: 579 if ((flags & (IP_FORWARDING|IP_NOIPNEWID)) == 0) { 580 if (m->m_pkthdr.len < IP_MINFRAGSIZE) { 581 ip->ip_id = 0; 582 } else if ((m->m_pkthdr.csum_flags & M_CSUM_TSOv4) == 0) { 583 ip->ip_id = ip_newid(ia); 584 } else { 585 /* 586 * TSO capable interfaces (typically?) increment 587 * ip_id for each segment. 588 * "allocate" enough ids here to increase the chance 589 * for them to be unique. 590 * 591 * note that the following calculation is not 592 * needed to be precise. wasting some ip_id is fine. 593 */ 594 595 unsigned int segsz = m->m_pkthdr.segsz; 596 unsigned int datasz = ntohs(ip->ip_len) - hlen; 597 unsigned int num = howmany(datasz, segsz); 598 599 ip->ip_id = ip_newid_range(ia, num); 600 } 601 } 602 if (ia != NULL) { 603 ia4_release(ia, &psref_ia); 604 ia = NULL; 605 } 606 607 /* 608 * If we're doing Path MTU Discovery, we need to set DF unless 609 * the route's MTU is locked. 610 */ 611 if ((flags & IP_MTUDISC) != 0 && rtmtu_nolock) { 612 ip->ip_off |= htons(IP_DF); 613 } 614 615 #ifdef IPSEC 616 if (ipsec_used) { 617 bool ipsec_done = false; 618 bool count_drop = false; 619 620 /* Perform IPsec processing, if any. */ 621 error = ipsec4_output(m, inp, flags, &mtu, &natt_frag, 622 &ipsec_done, &count_drop); 623 if (count_drop) 624 IP_STATINC(IP_STAT_IPSECDROP_OUT); 625 if (error || ipsec_done) 626 goto done; 627 } 628 629 if (!ipsec_used || !natt_frag) 630 #endif 631 { 632 /* 633 * Run through list of hooks for output packets. 634 */ 635 error = pfil_run_hooks(inet_pfil_hook, &m, ifp, PFIL_OUT); 636 if (error || m == NULL) { 637 IP_STATINC(IP_STAT_PFILDROP_OUT); 638 goto done; 639 } 640 } 641 642 ip = mtod(m, struct ip *); 643 hlen = ip->ip_hl << 2; 644 645 m->m_pkthdr.csum_data |= hlen << 16; 646 647 /* 648 * search for the source address structure to 649 * maintain output statistics, and verify address 650 * validity 651 */ 652 KASSERT(ia == NULL); 653 sockaddr_in_init(&usrc.sin, &ip->ip_src, 0); 654 ifa = ifaof_ifpforaddr_psref(&usrc.sa, ifp, &psref_ia); 655 if (ifa != NULL) 656 ia = ifatoia(ifa); 657 658 /* 659 * Ensure we only send from a valid address. 660 * A NULL address is valid because the packet could be 661 * generated from a packet filter. 662 */ 663 if (ia != NULL && (flags & IP_FORWARDING) == 0 && 664 (error = ip_ifaddrvalid(ia)) != 0) 665 { 666 ARPLOG(LOG_ERR, 667 "refusing to send from invalid address %s (pid %d)\n", 668 ARPLOGADDR(&ip->ip_src), curproc->p_pid); 669 IP_STATINC(IP_STAT_ODROPPED); 670 if (error == 1) 671 /* 672 * Address exists, but is tentative or detached. 673 * We can't send from it because it's invalid, 674 * so we drop the packet. 675 */ 676 error = 0; 677 else 678 error = EADDRNOTAVAIL; 679 goto bad; 680 } 681 682 /* Maybe skip checksums on loopback interfaces. */ 683 if (IN_NEED_CHECKSUM(ifp, M_CSUM_IPv4)) { 684 m->m_pkthdr.csum_flags |= M_CSUM_IPv4; 685 } 686 sw_csum = m->m_pkthdr.csum_flags & ~ifp->if_csum_flags_tx; 687 688 /* Need to fragment the packet */ 689 if (ntohs(ip->ip_len) > mtu && 690 (m->m_pkthdr.csum_flags & M_CSUM_TSOv4) == 0) { 691 goto fragment; 692 } 693 694 #if IFA_STATS 695 if (ia) 696 ia->ia_ifa.ifa_data.ifad_outbytes += ntohs(ip->ip_len); 697 #endif 698 /* 699 * Always initialize the sum to 0! Some HW assisted 700 * checksumming requires this. 701 */ 702 ip->ip_sum = 0; 703 704 if ((m->m_pkthdr.csum_flags & M_CSUM_TSOv4) == 0) { 705 /* 706 * Perform any checksums that the hardware can't do 707 * for us. 708 * 709 * XXX Does any hardware require the {th,uh}_sum 710 * XXX fields to be 0? 711 */ 712 if (sw_csum & M_CSUM_IPv4) { 713 KASSERT(IN_NEED_CHECKSUM(ifp, M_CSUM_IPv4)); 714 ip->ip_sum = in_cksum(m, hlen); 715 m->m_pkthdr.csum_flags &= ~M_CSUM_IPv4; 716 } 717 if (sw_csum & (M_CSUM_TCPv4|M_CSUM_UDPv4)) { 718 if (IN_NEED_CHECKSUM(ifp, 719 sw_csum & (M_CSUM_TCPv4|M_CSUM_UDPv4))) { 720 in_undefer_cksum_tcpudp(m); 721 } 722 m->m_pkthdr.csum_flags &= 723 ~(M_CSUM_TCPv4|M_CSUM_UDPv4); 724 } 725 } 726 727 sa = (m->m_flags & M_MCAST) ? sintocsa(rdst) : sintocsa(dst); 728 729 /* Send it */ 730 if (__predict_false(sw_csum & M_CSUM_TSOv4)) { 731 /* 732 * TSO4 is required by a packet, but disabled for 733 * the interface. 734 */ 735 error = ip_tso_output(ifp, m, sa, rt); 736 } else 737 error = ip_if_output(ifp, m, sa, rt); 738 goto done; 739 740 fragment: 741 /* 742 * We can't use HW checksumming if we're about to fragment the packet. 743 * 744 * XXX Some hardware can do this. 745 */ 746 if (m->m_pkthdr.csum_flags & (M_CSUM_TCPv4|M_CSUM_UDPv4)) { 747 if (IN_NEED_CHECKSUM(ifp, 748 m->m_pkthdr.csum_flags & (M_CSUM_TCPv4|M_CSUM_UDPv4))) { 749 in_undefer_cksum_tcpudp(m); 750 } 751 m->m_pkthdr.csum_flags &= ~(M_CSUM_TCPv4|M_CSUM_UDPv4); 752 } 753 754 /* 755 * Too large for interface; fragment if possible. 756 * Must be able to put at least 8 bytes per fragment. 757 */ 758 if (ntohs(ip->ip_off) & IP_DF) { 759 if (flags & IP_RETURNMTU) { 760 KASSERT(inp != NULL); 761 in4p_errormtu(inp) = mtu; 762 } 763 error = EMSGSIZE; 764 IP_STATINC(IP_STAT_CANTFRAG); 765 goto bad; 766 } 767 768 error = ip_fragment(m, ifp, mtu); 769 if (error) { 770 m = NULL; 771 goto bad; 772 } 773 774 for (; m; m = m0) { 775 m0 = m->m_nextpkt; 776 m->m_nextpkt = NULL; 777 if (error) { 778 m_freem(m); 779 continue; 780 } 781 #if IFA_STATS 782 if (ia) 783 ia->ia_ifa.ifa_data.ifad_outbytes += ntohs(ip->ip_len); 784 #endif 785 /* 786 * If we get there, the packet has not been handled by 787 * IPsec whereas it should have. Now that it has been 788 * fragmented, re-inject it in ip_output so that IPsec 789 * processing can occur. 790 */ 791 if (natt_frag) { 792 error = ip_output(m, opt, NULL, 793 flags | IP_RAWOUTPUT | IP_NOIPNEWID, 794 imo, inp); 795 } else { 796 KASSERT((m->m_pkthdr.csum_flags & 797 (M_CSUM_UDPv4 | M_CSUM_TCPv4)) == 0); 798 error = ip_if_output(ifp, m, (m->m_flags & M_MCAST) ? 799 sintocsa(rdst) : sintocsa(dst), rt); 800 } 801 } 802 if (error == 0) { 803 IP_STATINC(IP_STAT_FRAGMENTED); 804 } 805 806 done: 807 ia4_release(ia, &psref_ia); 808 rtcache_unref(rt, ro); 809 if (ro == &iproute) { 810 rtcache_free(&iproute); 811 } 812 if (mifp != NULL) { 813 if_put(mifp, &psref); 814 } 815 if (bind_need_restore) 816 curlwp_bindx(bound); 817 return error; 818 819 bad: 820 m_freem(m); 821 goto done; 822 } 823 824 int 825 ip_fragment(struct mbuf *m, struct ifnet *ifp, u_long mtu) 826 { 827 struct ip *ip, *mhip; 828 struct mbuf *m0; 829 int len, hlen, off; 830 int mhlen, firstlen; 831 struct mbuf **mnext; 832 int sw_csum = m->m_pkthdr.csum_flags; 833 int fragments = 0; 834 int error = 0; 835 int ipoff, ipflg; 836 837 ip = mtod(m, struct ip *); 838 hlen = ip->ip_hl << 2; 839 840 /* Preserve the offset and flags. */ 841 ipoff = ntohs(ip->ip_off) & IP_OFFMASK; 842 ipflg = ntohs(ip->ip_off) & (IP_RF|IP_DF|IP_MF); 843 844 if (ifp != NULL) 845 sw_csum &= ~ifp->if_csum_flags_tx; 846 847 len = (mtu - hlen) &~ 7; 848 if (len < 8) { 849 IP_STATINC(IP_STAT_CANTFRAG); 850 m_freem(m); 851 return EMSGSIZE; 852 } 853 854 firstlen = len; 855 mnext = &m->m_nextpkt; 856 857 /* 858 * Loop through length of segment after first fragment, 859 * make new header and copy data of each part and link onto chain. 860 */ 861 m0 = m; 862 mhlen = sizeof(struct ip); 863 for (off = hlen + len; off < ntohs(ip->ip_len); off += len) { 864 MGETHDR(m, M_DONTWAIT, MT_HEADER); 865 if (m == NULL) { 866 error = ENOBUFS; 867 IP_STATINC(IP_STAT_ODROPPED); 868 goto sendorfree; 869 } 870 MCLAIM(m, m0->m_owner); 871 872 *mnext = m; 873 mnext = &m->m_nextpkt; 874 875 m->m_data += max_linkhdr; 876 mhip = mtod(m, struct ip *); 877 *mhip = *ip; 878 879 /* we must inherit the flags */ 880 m->m_flags |= m0->m_flags & M_COPYFLAGS; 881 882 if (hlen > sizeof(struct ip)) { 883 mhlen = ip_optcopy(ip, mhip) + sizeof(struct ip); 884 mhip->ip_hl = mhlen >> 2; 885 } 886 m->m_len = mhlen; 887 888 mhip->ip_off = ((off - hlen) >> 3) + ipoff; 889 mhip->ip_off |= ipflg; 890 if (off + len >= ntohs(ip->ip_len)) 891 len = ntohs(ip->ip_len) - off; 892 else 893 mhip->ip_off |= IP_MF; 894 HTONS(mhip->ip_off); 895 896 mhip->ip_len = htons((u_int16_t)(len + mhlen)); 897 m->m_next = m_copym(m0, off, len, M_DONTWAIT); 898 if (m->m_next == NULL) { 899 error = ENOBUFS; 900 IP_STATINC(IP_STAT_ODROPPED); 901 goto sendorfree; 902 } 903 904 m->m_pkthdr.len = mhlen + len; 905 m_reset_rcvif(m); 906 907 mhip->ip_sum = 0; 908 KASSERT((m->m_pkthdr.csum_flags & M_CSUM_IPv4) == 0); 909 if (sw_csum & M_CSUM_IPv4) { 910 mhip->ip_sum = in_cksum(m, mhlen); 911 } else { 912 /* 913 * checksum is hw-offloaded or not necessary. 914 */ 915 m->m_pkthdr.csum_flags |= 916 m0->m_pkthdr.csum_flags & M_CSUM_IPv4; 917 m->m_pkthdr.csum_data |= mhlen << 16; 918 KASSERT(!(ifp != NULL && 919 IN_NEED_CHECKSUM(ifp, M_CSUM_IPv4)) || 920 (m->m_pkthdr.csum_flags & M_CSUM_IPv4) != 0); 921 } 922 IP_STATINC(IP_STAT_OFRAGMENTS); 923 fragments++; 924 } 925 926 /* 927 * Update first fragment by trimming what's been copied out 928 * and updating header, then send each fragment (in order). 929 */ 930 m = m0; 931 m_adj(m, hlen + firstlen - ntohs(ip->ip_len)); 932 m->m_pkthdr.len = hlen + firstlen; 933 ip->ip_len = htons((u_int16_t)m->m_pkthdr.len); 934 ip->ip_off |= htons(IP_MF); 935 ip->ip_sum = 0; 936 if (sw_csum & M_CSUM_IPv4) { 937 ip->ip_sum = in_cksum(m, hlen); 938 m->m_pkthdr.csum_flags &= ~M_CSUM_IPv4; 939 } else { 940 /* 941 * checksum is hw-offloaded or not necessary. 942 */ 943 KASSERT(!(ifp != NULL && IN_NEED_CHECKSUM(ifp, M_CSUM_IPv4)) || 944 (m->m_pkthdr.csum_flags & M_CSUM_IPv4) != 0); 945 KASSERT(M_CSUM_DATA_IPv4_IPHL(m->m_pkthdr.csum_data) >= 946 sizeof(struct ip)); 947 } 948 949 sendorfree: 950 /* 951 * If there is no room for all the fragments, don't queue 952 * any of them. 953 */ 954 if (ifp != NULL) { 955 IFQ_LOCK(&ifp->if_snd); 956 if (ifp->if_snd.ifq_maxlen - ifp->if_snd.ifq_len < fragments && 957 error == 0) { 958 error = ENOBUFS; 959 IP_STATINC(IP_STAT_ODROPPED); 960 IFQ_INC_DROPS(&ifp->if_snd); 961 } 962 IFQ_UNLOCK(&ifp->if_snd); 963 } 964 if (error) { 965 for (m = m0; m; m = m0) { 966 m0 = m->m_nextpkt; 967 m->m_nextpkt = NULL; 968 m_freem(m); 969 } 970 } 971 972 return error; 973 } 974 975 /* 976 * Determine the maximum length of the options to be inserted; 977 * we would far rather allocate too much space rather than too little. 978 */ 979 u_int 980 ip_optlen(struct inpcb *inp) 981 { 982 struct mbuf *m = inp->inp_options; 983 984 if (m && m->m_len > offsetof(struct ipoption, ipopt_dst)) { 985 return (m->m_len - offsetof(struct ipoption, ipopt_dst)); 986 } 987 return 0; 988 } 989 990 /* 991 * Insert IP options into preformed packet. 992 * Adjust IP destination as required for IP source routing, 993 * as indicated by a non-zero in_addr at the start of the options. 994 */ 995 static struct mbuf * 996 ip_insertoptions(struct mbuf *m, struct mbuf *opt, int *phlen) 997 { 998 struct ipoption *p = mtod(opt, struct ipoption *); 999 struct mbuf *n; 1000 struct ip *ip = mtod(m, struct ip *); 1001 unsigned optlen; 1002 1003 optlen = opt->m_len - sizeof(p->ipopt_dst); 1004 KASSERT(optlen % 4 == 0); 1005 if (optlen + ntohs(ip->ip_len) > IP_MAXPACKET) 1006 return m; /* XXX should fail */ 1007 if (!in_nullhost(p->ipopt_dst)) 1008 ip->ip_dst = p->ipopt_dst; 1009 if (M_READONLY(m) || M_LEADINGSPACE(m) < optlen) { 1010 MGETHDR(n, M_DONTWAIT, MT_HEADER); 1011 if (n == NULL) 1012 return m; 1013 MCLAIM(n, m->m_owner); 1014 m_move_pkthdr(n, m); 1015 m->m_len -= sizeof(struct ip); 1016 m->m_data += sizeof(struct ip); 1017 n->m_next = m; 1018 n->m_len = optlen + sizeof(struct ip); 1019 n->m_data += max_linkhdr; 1020 memcpy(mtod(n, void *), ip, sizeof(struct ip)); 1021 m = n; 1022 } else { 1023 m->m_data -= optlen; 1024 m->m_len += optlen; 1025 memmove(mtod(m, void *), ip, sizeof(struct ip)); 1026 } 1027 m->m_pkthdr.len += optlen; 1028 ip = mtod(m, struct ip *); 1029 memcpy(ip + 1, p->ipopt_list, optlen); 1030 *phlen = sizeof(struct ip) + optlen; 1031 ip->ip_len = htons(ntohs(ip->ip_len) + optlen); 1032 return m; 1033 } 1034 1035 /* 1036 * Copy options from ipsrc to ipdst, omitting those not copied during 1037 * fragmentation. 1038 */ 1039 int 1040 ip_optcopy(struct ip *ipsrc, struct ip *ipdst) 1041 { 1042 u_char *cp, *dp; 1043 int opt, optlen, cnt; 1044 1045 cp = (u_char *)(ipsrc + 1); 1046 dp = (u_char *)(ipdst + 1); 1047 cnt = (ipsrc->ip_hl << 2) - sizeof(struct ip); 1048 for (; cnt > 0; cnt -= optlen, cp += optlen) { 1049 opt = cp[0]; 1050 if (opt == IPOPT_EOL) 1051 break; 1052 if (opt == IPOPT_NOP) { 1053 /* Preserve for IP mcast tunnel's LSRR alignment. */ 1054 *dp++ = IPOPT_NOP; 1055 optlen = 1; 1056 continue; 1057 } 1058 1059 KASSERT(cnt >= IPOPT_OLEN + sizeof(*cp)); 1060 optlen = cp[IPOPT_OLEN]; 1061 KASSERT(optlen >= IPOPT_OLEN + sizeof(*cp) && optlen < cnt); 1062 1063 /* Invalid lengths should have been caught by ip_dooptions. */ 1064 if (optlen > cnt) 1065 optlen = cnt; 1066 if (IPOPT_COPIED(opt)) { 1067 bcopy((void *)cp, (void *)dp, (unsigned)optlen); 1068 dp += optlen; 1069 } 1070 } 1071 1072 for (optlen = dp - (u_char *)(ipdst+1); optlen & 0x3; optlen++) { 1073 *dp++ = IPOPT_EOL; 1074 } 1075 1076 return optlen; 1077 } 1078 1079 /* 1080 * IP socket option processing. 1081 */ 1082 int 1083 ip_ctloutput(int op, struct socket *so, struct sockopt *sopt) 1084 { 1085 struct inpcb *inp = sotoinpcb(so); 1086 struct ip *ip = &in4p_ip(inp); 1087 int inpflags = inp->inp_flags; 1088 int optval = 0, error = 0; 1089 struct in_pktinfo pktinfo; 1090 1091 KASSERT(solocked(so)); 1092 1093 if (sopt->sopt_level != IPPROTO_IP) { 1094 if (sopt->sopt_level == SOL_SOCKET && sopt->sopt_name == SO_NOHEADER) 1095 return 0; 1096 return ENOPROTOOPT; 1097 } 1098 1099 switch (op) { 1100 case PRCO_SETOPT: 1101 switch (sopt->sopt_name) { 1102 case IP_OPTIONS: 1103 #ifdef notyet 1104 case IP_RETOPTS: 1105 #endif 1106 error = ip_pcbopts(inp, sopt); 1107 break; 1108 1109 case IP_TOS: 1110 case IP_TTL: 1111 case IP_MINTTL: 1112 case IP_RECVOPTS: 1113 case IP_RECVRETOPTS: 1114 case IP_RECVDSTADDR: 1115 case IP_RECVIF: 1116 case IP_RECVPKTINFO: 1117 case IP_RECVTTL: 1118 case IP_BINDANY: 1119 error = sockopt_getint(sopt, &optval); 1120 if (error) 1121 break; 1122 1123 switch (sopt->sopt_name) { 1124 case IP_TOS: 1125 ip->ip_tos = optval; 1126 break; 1127 1128 case IP_TTL: 1129 ip->ip_ttl = optval; 1130 break; 1131 1132 case IP_MINTTL: 1133 if (optval > 0 && optval <= MAXTTL) 1134 in4p_ip_minttl(inp) = optval; 1135 else 1136 error = EINVAL; 1137 break; 1138 #define OPTSET(bit) \ 1139 if (optval) \ 1140 inpflags |= bit; \ 1141 else \ 1142 inpflags &= ~bit; 1143 1144 case IP_RECVOPTS: 1145 OPTSET(INP_RECVOPTS); 1146 break; 1147 1148 case IP_RECVPKTINFO: 1149 OPTSET(INP_RECVPKTINFO); 1150 break; 1151 1152 case IP_RECVRETOPTS: 1153 OPTSET(INP_RECVRETOPTS); 1154 break; 1155 1156 case IP_RECVDSTADDR: 1157 OPTSET(INP_RECVDSTADDR); 1158 break; 1159 1160 case IP_RECVIF: 1161 OPTSET(INP_RECVIF); 1162 break; 1163 1164 case IP_RECVTTL: 1165 OPTSET(INP_RECVTTL); 1166 break; 1167 1168 case IP_BINDANY: 1169 error = kauth_authorize_network( 1170 kauth_cred_get(), KAUTH_NETWORK_BIND, 1171 KAUTH_REQ_NETWORK_BIND_ANYADDR, so, 1172 NULL, NULL); 1173 if (error == 0) { 1174 OPTSET(INP_BINDANY); 1175 } 1176 break; 1177 } 1178 break; 1179 case IP_PKTINFO: 1180 error = sockopt_getint(sopt, &optval); 1181 if (!error) { 1182 /* Linux compatibility */ 1183 OPTSET(INP_RECVPKTINFO); 1184 break; 1185 } 1186 error = sockopt_get(sopt, &pktinfo, sizeof(pktinfo)); 1187 if (error) 1188 break; 1189 1190 if (pktinfo.ipi_ifindex == 0) { 1191 in4p_prefsrcip(inp) = pktinfo.ipi_addr; 1192 break; 1193 } 1194 1195 /* Solaris compatibility */ 1196 struct ifnet *ifp; 1197 struct in_ifaddr *ia; 1198 int s; 1199 1200 /* pick up primary address */ 1201 s = pserialize_read_enter(); 1202 ifp = if_byindex(pktinfo.ipi_ifindex); 1203 if (ifp == NULL) { 1204 pserialize_read_exit(s); 1205 error = EADDRNOTAVAIL; 1206 break; 1207 } 1208 ia = in_get_ia_from_ifp(ifp); 1209 if (ia == NULL) { 1210 pserialize_read_exit(s); 1211 error = EADDRNOTAVAIL; 1212 break; 1213 } 1214 in4p_prefsrcip(inp) = IA_SIN(ia)->sin_addr; 1215 pserialize_read_exit(s); 1216 break; 1217 break; 1218 #undef OPTSET 1219 1220 case IP_MULTICAST_IF: 1221 case IP_MULTICAST_TTL: 1222 case IP_MULTICAST_LOOP: 1223 case IP_ADD_MEMBERSHIP: 1224 case IP_DROP_MEMBERSHIP: 1225 error = ip_setmoptions(&inp->inp_moptions, sopt); 1226 break; 1227 1228 case IP_PORTRANGE: 1229 error = sockopt_getint(sopt, &optval); 1230 if (error) 1231 break; 1232 1233 switch (optval) { 1234 case IP_PORTRANGE_DEFAULT: 1235 case IP_PORTRANGE_HIGH: 1236 inpflags &= ~(INP_LOWPORT); 1237 break; 1238 1239 case IP_PORTRANGE_LOW: 1240 inpflags |= INP_LOWPORT; 1241 break; 1242 1243 default: 1244 error = EINVAL; 1245 break; 1246 } 1247 break; 1248 1249 case IP_PORTALGO: 1250 error = sockopt_getint(sopt, &optval); 1251 if (error) 1252 break; 1253 1254 error = portalgo_algo_index_select(inp, optval); 1255 break; 1256 1257 #if defined(IPSEC) 1258 case IP_IPSEC_POLICY: 1259 if (ipsec_enabled) { 1260 error = ipsec_set_policy(inp, 1261 sopt->sopt_data, sopt->sopt_size, 1262 curlwp->l_cred); 1263 } else 1264 error = ENOPROTOOPT; 1265 break; 1266 #endif /* IPSEC */ 1267 1268 default: 1269 error = ENOPROTOOPT; 1270 break; 1271 } 1272 break; 1273 1274 case PRCO_GETOPT: 1275 switch (sopt->sopt_name) { 1276 case IP_OPTIONS: 1277 case IP_RETOPTS: { 1278 struct mbuf *mopts = inp->inp_options; 1279 1280 if (mopts) { 1281 struct mbuf *m; 1282 1283 m = m_copym(mopts, 0, M_COPYALL, M_DONTWAIT); 1284 if (m == NULL) { 1285 error = ENOBUFS; 1286 break; 1287 } 1288 error = sockopt_setmbuf(sopt, m); 1289 } 1290 break; 1291 } 1292 case IP_TOS: 1293 case IP_TTL: 1294 case IP_MINTTL: 1295 case IP_RECVOPTS: 1296 case IP_RECVRETOPTS: 1297 case IP_RECVDSTADDR: 1298 case IP_RECVIF: 1299 case IP_RECVPKTINFO: 1300 case IP_RECVTTL: 1301 case IP_ERRORMTU: 1302 case IP_BINDANY: 1303 switch (sopt->sopt_name) { 1304 case IP_TOS: 1305 optval = ip->ip_tos; 1306 break; 1307 1308 case IP_TTL: 1309 optval = ip->ip_ttl; 1310 break; 1311 1312 case IP_MINTTL: 1313 optval = in4p_ip_minttl(inp); 1314 break; 1315 1316 case IP_ERRORMTU: 1317 optval = in4p_errormtu(inp); 1318 break; 1319 1320 #define OPTBIT(bit) (inpflags & bit ? 1 : 0) 1321 1322 case IP_RECVOPTS: 1323 optval = OPTBIT(INP_RECVOPTS); 1324 break; 1325 1326 case IP_RECVPKTINFO: 1327 optval = OPTBIT(INP_RECVPKTINFO); 1328 break; 1329 1330 case IP_RECVRETOPTS: 1331 optval = OPTBIT(INP_RECVRETOPTS); 1332 break; 1333 1334 case IP_RECVDSTADDR: 1335 optval = OPTBIT(INP_RECVDSTADDR); 1336 break; 1337 1338 case IP_RECVIF: 1339 optval = OPTBIT(INP_RECVIF); 1340 break; 1341 1342 case IP_RECVTTL: 1343 optval = OPTBIT(INP_RECVTTL); 1344 break; 1345 1346 case IP_BINDANY: 1347 optval = OPTBIT(INP_BINDANY); 1348 break; 1349 } 1350 error = sockopt_setint(sopt, optval); 1351 break; 1352 1353 case IP_PKTINFO: 1354 switch (sopt->sopt_size) { 1355 case sizeof(int): 1356 /* Linux compatibility */ 1357 optval = OPTBIT(INP_RECVPKTINFO); 1358 error = sockopt_setint(sopt, optval); 1359 break; 1360 case sizeof(struct in_pktinfo): 1361 /* Solaris compatibility */ 1362 pktinfo.ipi_ifindex = 0; 1363 pktinfo.ipi_addr = in4p_prefsrcip(inp); 1364 error = sockopt_set(sopt, &pktinfo, 1365 sizeof(pktinfo)); 1366 break; 1367 default: 1368 /* 1369 * While size is stuck at 0, and, later, if 1370 * the caller doesn't use an exactly sized 1371 * recipient for the data, default to Linux 1372 * compatibility 1373 */ 1374 optval = OPTBIT(INP_RECVPKTINFO); 1375 error = sockopt_setint(sopt, optval); 1376 break; 1377 } 1378 break; 1379 1380 #if 0 /* defined(IPSEC) */ 1381 case IP_IPSEC_POLICY: 1382 { 1383 struct mbuf *m = NULL; 1384 1385 /* XXX this will return EINVAL as sopt is empty */ 1386 error = ipsec_get_policy(inp, sopt->sopt_data, 1387 sopt->sopt_size, &m); 1388 if (error == 0) 1389 error = sockopt_setmbuf(sopt, m); 1390 break; 1391 } 1392 #endif /*IPSEC*/ 1393 1394 case IP_MULTICAST_IF: 1395 case IP_MULTICAST_TTL: 1396 case IP_MULTICAST_LOOP: 1397 case IP_ADD_MEMBERSHIP: 1398 case IP_DROP_MEMBERSHIP: 1399 error = ip_getmoptions(inp->inp_moptions, sopt); 1400 break; 1401 1402 case IP_PORTRANGE: 1403 if (inpflags & INP_LOWPORT) 1404 optval = IP_PORTRANGE_LOW; 1405 else 1406 optval = IP_PORTRANGE_DEFAULT; 1407 error = sockopt_setint(sopt, optval); 1408 break; 1409 1410 case IP_PORTALGO: 1411 optval = inp->inp_portalgo; 1412 error = sockopt_setint(sopt, optval); 1413 break; 1414 1415 default: 1416 error = ENOPROTOOPT; 1417 break; 1418 } 1419 break; 1420 } 1421 1422 if (!error) { 1423 inp->inp_flags = inpflags; 1424 } 1425 return error; 1426 } 1427 1428 static int 1429 ip_pktinfo_prepare(const struct inpcb *inp, const struct in_pktinfo *pktinfo, 1430 struct ip_pktopts *pktopts, int *flags, kauth_cred_t cred) 1431 { 1432 struct ip_moptions *imo; 1433 int error = 0; 1434 bool addrset = false; 1435 1436 if (!in_nullhost(pktinfo->ipi_addr)) { 1437 pktopts->ippo_laddr.sin_addr = pktinfo->ipi_addr; 1438 /* EADDRNOTAVAIL? */ 1439 error = inpcb_bindableaddr(inp, &pktopts->ippo_laddr, cred); 1440 if (error != 0) 1441 return error; 1442 addrset = true; 1443 } 1444 1445 if (pktinfo->ipi_ifindex != 0) { 1446 if (!addrset) { 1447 struct ifnet *ifp; 1448 struct in_ifaddr *ia; 1449 int s; 1450 1451 /* pick up primary address */ 1452 s = pserialize_read_enter(); 1453 ifp = if_byindex(pktinfo->ipi_ifindex); 1454 if (ifp == NULL) { 1455 pserialize_read_exit(s); 1456 return EADDRNOTAVAIL; 1457 } 1458 ia = in_get_ia_from_ifp(ifp); 1459 if (ia == NULL) { 1460 pserialize_read_exit(s); 1461 return EADDRNOTAVAIL; 1462 } 1463 pktopts->ippo_laddr.sin_addr = IA_SIN(ia)->sin_addr; 1464 pserialize_read_exit(s); 1465 } 1466 1467 /* 1468 * If specified ipi_ifindex, 1469 * use copied or locally initialized ip_moptions. 1470 * Original ip_moptions must not be modified. 1471 */ 1472 imo = &pktopts->ippo_imobuf; /* local buf in pktopts */ 1473 if (pktopts->ippo_imo != NULL) { 1474 memcpy(imo, pktopts->ippo_imo, sizeof(*imo)); 1475 } else { 1476 memset(imo, 0, sizeof(*imo)); 1477 imo->imo_multicast_ttl = IP_DEFAULT_MULTICAST_TTL; 1478 imo->imo_multicast_loop = IP_DEFAULT_MULTICAST_LOOP; 1479 } 1480 imo->imo_multicast_if_index = pktinfo->ipi_ifindex; 1481 pktopts->ippo_imo = imo; 1482 *flags |= IP_ROUTETOIFINDEX; 1483 } 1484 return error; 1485 } 1486 1487 /* 1488 * Set up IP outgoing packet options. Even if control is NULL, 1489 * pktopts->ippo_laddr and pktopts->ippo_imo are set and used. 1490 */ 1491 int 1492 ip_setpktopts(struct mbuf *control, struct ip_pktopts *pktopts, int *flags, 1493 struct inpcb *inp, kauth_cred_t cred) 1494 { 1495 struct cmsghdr *cm; 1496 struct in_pktinfo pktinfo; 1497 int error; 1498 1499 pktopts->ippo_imo = inp->inp_moptions; 1500 1501 struct in_addr *ia = in_nullhost(in4p_prefsrcip(inp)) ? &in4p_laddr(inp) : 1502 &in4p_prefsrcip(inp); 1503 sockaddr_in_init(&pktopts->ippo_laddr, ia, 0); 1504 1505 if (control == NULL) 1506 return 0; 1507 1508 /* 1509 * XXX: Currently, we assume all the optional information is 1510 * stored in a single mbuf. 1511 */ 1512 if (control->m_next) 1513 return EINVAL; 1514 1515 for (; control->m_len > 0; 1516 control->m_data += CMSG_ALIGN(cm->cmsg_len), 1517 control->m_len -= CMSG_ALIGN(cm->cmsg_len)) { 1518 cm = mtod(control, struct cmsghdr *); 1519 if ((control->m_len < sizeof(*cm)) || 1520 (cm->cmsg_len == 0) || 1521 (cm->cmsg_len > control->m_len)) { 1522 return EINVAL; 1523 } 1524 if (cm->cmsg_level != IPPROTO_IP) 1525 continue; 1526 1527 switch (cm->cmsg_type) { 1528 case IP_PKTINFO: 1529 if (cm->cmsg_len != CMSG_LEN(sizeof(pktinfo))) 1530 return EINVAL; 1531 memcpy(&pktinfo, CMSG_DATA(cm), sizeof(pktinfo)); 1532 error = ip_pktinfo_prepare(inp, &pktinfo, pktopts, 1533 flags, cred); 1534 if (error) 1535 return error; 1536 break; 1537 case IP_SENDSRCADDR: /* FreeBSD compatibility */ 1538 if (cm->cmsg_len != CMSG_LEN(sizeof(struct in_addr))) 1539 return EINVAL; 1540 pktinfo.ipi_ifindex = 0; 1541 pktinfo.ipi_addr = 1542 ((struct in_pktinfo *)CMSG_DATA(cm))->ipi_addr; 1543 error = ip_pktinfo_prepare(inp, &pktinfo, pktopts, 1544 flags, cred); 1545 if (error) 1546 return error; 1547 break; 1548 default: 1549 return ENOPROTOOPT; 1550 } 1551 } 1552 return 0; 1553 } 1554 1555 /* 1556 * Set up IP options in pcb for insertion in output packets. 1557 * Store in mbuf with pointer in pcbopt, adding pseudo-option 1558 * with destination address if source routed. 1559 */ 1560 static int 1561 ip_pcbopts(struct inpcb *inp, const struct sockopt *sopt) 1562 { 1563 struct mbuf *m; 1564 const u_char *cp; 1565 u_char *dp; 1566 int cnt; 1567 1568 KASSERT(inp_locked(inp)); 1569 1570 /* Turn off any old options. */ 1571 if (inp->inp_options) { 1572 m_free(inp->inp_options); 1573 } 1574 inp->inp_options = NULL; 1575 if ((cnt = sopt->sopt_size) == 0) { 1576 /* Only turning off any previous options. */ 1577 return 0; 1578 } 1579 cp = sopt->sopt_data; 1580 1581 if (cnt % 4) { 1582 /* Must be 4-byte aligned, because there's no padding. */ 1583 return EINVAL; 1584 } 1585 1586 m = m_get(M_DONTWAIT, MT_SOOPTS); 1587 if (m == NULL) 1588 return ENOBUFS; 1589 1590 dp = mtod(m, u_char *); 1591 memset(dp, 0, sizeof(struct in_addr)); 1592 dp += sizeof(struct in_addr); 1593 m->m_len = sizeof(struct in_addr); 1594 1595 /* 1596 * IP option list according to RFC791. Each option is of the form 1597 * 1598 * [optval] [olen] [(olen - 2) data bytes] 1599 * 1600 * We validate the list and copy options to an mbuf for prepending 1601 * to data packets. The IP first-hop destination address will be 1602 * stored before actual options and is zero if unset. 1603 */ 1604 while (cnt > 0) { 1605 uint8_t optval, olen, offset; 1606 1607 optval = cp[IPOPT_OPTVAL]; 1608 1609 if (optval == IPOPT_EOL || optval == IPOPT_NOP) { 1610 olen = 1; 1611 } else { 1612 if (cnt < IPOPT_OLEN + 1) 1613 goto bad; 1614 1615 olen = cp[IPOPT_OLEN]; 1616 if (olen < IPOPT_OLEN + 1 || olen > cnt) 1617 goto bad; 1618 } 1619 1620 if (optval == IPOPT_LSRR || optval == IPOPT_SSRR) { 1621 /* 1622 * user process specifies route as: 1623 * ->A->B->C->D 1624 * D must be our final destination (but we can't 1625 * check that since we may not have connected yet). 1626 * A is first hop destination, which doesn't appear in 1627 * actual IP option, but is stored before the options. 1628 */ 1629 if (olen < IPOPT_OFFSET + 1 + sizeof(struct in_addr)) 1630 goto bad; 1631 1632 offset = cp[IPOPT_OFFSET]; 1633 memcpy(mtod(m, u_char *), cp + IPOPT_OFFSET + 1, 1634 sizeof(struct in_addr)); 1635 1636 cp += sizeof(struct in_addr); 1637 cnt -= sizeof(struct in_addr); 1638 olen -= sizeof(struct in_addr); 1639 1640 if (m->m_len + olen > MAX_IPOPTLEN + sizeof(struct in_addr)) 1641 goto bad; 1642 1643 memcpy(dp, cp, olen); 1644 dp[IPOPT_OPTVAL] = optval; 1645 dp[IPOPT_OLEN] = olen; 1646 dp[IPOPT_OFFSET] = offset; 1647 break; 1648 } else { 1649 if (m->m_len + olen > MAX_IPOPTLEN + sizeof(struct in_addr)) 1650 goto bad; 1651 1652 memcpy(dp, cp, olen); 1653 break; 1654 } 1655 1656 dp += olen; 1657 m->m_len += olen; 1658 1659 if (optval == IPOPT_EOL) 1660 break; 1661 1662 cp += olen; 1663 cnt -= olen; 1664 } 1665 1666 inp->inp_options = m; 1667 return 0; 1668 1669 bad: 1670 (void)m_free(m); 1671 return EINVAL; 1672 } 1673 1674 /* 1675 * following RFC1724 section 3.3, 0.0.0.0/8 is interpreted as interface index. 1676 * Must be called in a pserialize critical section. 1677 */ 1678 static struct ifnet * 1679 ip_multicast_if(struct in_addr *a, int *ifindexp) 1680 { 1681 int ifindex; 1682 struct ifnet *ifp = NULL; 1683 struct in_ifaddr *ia; 1684 1685 if (ifindexp) 1686 *ifindexp = 0; 1687 if (ntohl(a->s_addr) >> 24 == 0) { 1688 ifindex = ntohl(a->s_addr) & 0xffffff; 1689 ifp = if_byindex(ifindex); 1690 if (!ifp) 1691 return NULL; 1692 if (ifindexp) 1693 *ifindexp = ifindex; 1694 } else { 1695 IN_ADDRHASH_READER_FOREACH(ia, a->s_addr) { 1696 if (in_hosteq(ia->ia_addr.sin_addr, *a) && 1697 (ia->ia_ifp->if_flags & IFF_MULTICAST) != 0) { 1698 ifp = ia->ia_ifp; 1699 if (if_is_deactivated(ifp)) 1700 ifp = NULL; 1701 break; 1702 } 1703 } 1704 } 1705 return ifp; 1706 } 1707 1708 static int 1709 ip_getoptval(const struct sockopt *sopt, u_int8_t *val, u_int maxval) 1710 { 1711 u_int tval; 1712 u_char cval; 1713 int error; 1714 1715 if (sopt == NULL) 1716 return EINVAL; 1717 1718 switch (sopt->sopt_size) { 1719 case sizeof(u_char): 1720 error = sockopt_get(sopt, &cval, sizeof(u_char)); 1721 tval = cval; 1722 break; 1723 1724 case sizeof(u_int): 1725 error = sockopt_get(sopt, &tval, sizeof(u_int)); 1726 break; 1727 1728 default: 1729 error = EINVAL; 1730 } 1731 1732 if (error) 1733 return error; 1734 1735 if (tval > maxval) 1736 return EINVAL; 1737 1738 *val = tval; 1739 return 0; 1740 } 1741 1742 static int 1743 ip_get_membership(const struct sockopt *sopt, struct ifnet **ifp, 1744 struct psref *psref, struct in_addr *ia, bool add) 1745 { 1746 int error; 1747 struct ip_mreq mreq; 1748 1749 error = sockopt_get(sopt, &mreq, sizeof(mreq)); 1750 if (error) 1751 return error; 1752 1753 if (!IN_MULTICAST(mreq.imr_multiaddr.s_addr)) 1754 return EINVAL; 1755 1756 memcpy(ia, &mreq.imr_multiaddr, sizeof(*ia)); 1757 1758 if (in_nullhost(mreq.imr_interface)) { 1759 union { 1760 struct sockaddr dst; 1761 struct sockaddr_in dst4; 1762 } u; 1763 struct route ro; 1764 1765 if (!add) { 1766 *ifp = NULL; 1767 return 0; 1768 } 1769 /* 1770 * If no interface address was provided, use the interface of 1771 * the route to the given multicast address. 1772 */ 1773 struct rtentry *rt; 1774 memset(&ro, 0, sizeof(ro)); 1775 1776 sockaddr_in_init(&u.dst4, ia, 0); 1777 error = rtcache_setdst(&ro, &u.dst); 1778 if (error != 0) 1779 return error; 1780 *ifp = (rt = rtcache_init(&ro)) != NULL ? rt->rt_ifp : NULL; 1781 if (*ifp != NULL) { 1782 if (if_is_deactivated(*ifp)) 1783 *ifp = NULL; 1784 else 1785 if_acquire(*ifp, psref); 1786 } 1787 rtcache_unref(rt, &ro); 1788 rtcache_free(&ro); 1789 } else { 1790 int s = pserialize_read_enter(); 1791 *ifp = ip_multicast_if(&mreq.imr_interface, NULL); 1792 if (!add && *ifp == NULL) { 1793 pserialize_read_exit(s); 1794 return EADDRNOTAVAIL; 1795 } 1796 if (*ifp != NULL) { 1797 if (if_is_deactivated(*ifp)) 1798 *ifp = NULL; 1799 else 1800 if_acquire(*ifp, psref); 1801 } 1802 pserialize_read_exit(s); 1803 } 1804 return 0; 1805 } 1806 1807 /* 1808 * Add a multicast group membership. 1809 * Group must be a valid IP multicast address. 1810 */ 1811 static int 1812 ip_add_membership(struct ip_moptions *imo, const struct sockopt *sopt) 1813 { 1814 struct ifnet *ifp = NULL; // XXX: gcc [ppc] 1815 struct in_addr ia; 1816 int i, error, bound; 1817 struct psref psref; 1818 1819 /* imo is protected by solock or referenced only by the caller */ 1820 1821 bound = curlwp_bind(); 1822 if (sopt->sopt_size == sizeof(struct ip_mreq)) 1823 error = ip_get_membership(sopt, &ifp, &psref, &ia, true); 1824 else { 1825 #ifdef INET6 1826 error = ip6_get_membership(sopt, &ifp, &psref, &ia, sizeof(ia)); 1827 #else 1828 error = EINVAL; 1829 #endif 1830 } 1831 1832 if (error) 1833 goto out; 1834 1835 /* 1836 * See if we found an interface, and confirm that it 1837 * supports multicast. 1838 */ 1839 if (ifp == NULL || (ifp->if_flags & IFF_MULTICAST) == 0) { 1840 error = EADDRNOTAVAIL; 1841 goto out; 1842 } 1843 1844 /* 1845 * See if the membership already exists or if all the 1846 * membership slots are full. 1847 */ 1848 for (i = 0; i < imo->imo_num_memberships; ++i) { 1849 if (imo->imo_membership[i]->inm_ifp == ifp && 1850 in_hosteq(imo->imo_membership[i]->inm_addr, ia)) 1851 break; 1852 } 1853 if (i < imo->imo_num_memberships) { 1854 error = EADDRINUSE; 1855 goto out; 1856 } 1857 1858 if (i == IP_MAX_MEMBERSHIPS) { 1859 error = ETOOMANYREFS; 1860 goto out; 1861 } 1862 1863 /* 1864 * Everything looks good; add a new record to the multicast 1865 * address list for the given interface. 1866 */ 1867 imo->imo_membership[i] = in_addmulti(&ia, ifp); 1868 if (imo->imo_membership[i] == NULL) { 1869 error = ENOBUFS; 1870 goto out; 1871 } 1872 1873 ++imo->imo_num_memberships; 1874 error = 0; 1875 out: 1876 if_put(ifp, &psref); 1877 curlwp_bindx(bound); 1878 return error; 1879 } 1880 1881 /* 1882 * Drop a multicast group membership. 1883 * Group must be a valid IP multicast address. 1884 */ 1885 static int 1886 ip_drop_membership(struct ip_moptions *imo, const struct sockopt *sopt) 1887 { 1888 struct in_addr ia = { .s_addr = 0 }; // XXX: gcc [ppc] 1889 struct ifnet *ifp = NULL; // XXX: gcc [ppc] 1890 int i, error, bound; 1891 struct psref psref; 1892 1893 /* imo is protected by solock or referenced only by the caller */ 1894 1895 bound = curlwp_bind(); 1896 if (sopt->sopt_size == sizeof(struct ip_mreq)) 1897 error = ip_get_membership(sopt, &ifp, &psref, &ia, false); 1898 else { 1899 #ifdef INET6 1900 error = ip6_get_membership(sopt, &ifp, &psref, &ia, sizeof(ia)); 1901 #else 1902 error = EINVAL; 1903 #endif 1904 } 1905 1906 if (error) 1907 goto out; 1908 1909 /* 1910 * Find the membership in the membership array. 1911 */ 1912 for (i = 0; i < imo->imo_num_memberships; ++i) { 1913 if ((ifp == NULL || 1914 imo->imo_membership[i]->inm_ifp == ifp) && 1915 in_hosteq(imo->imo_membership[i]->inm_addr, ia)) 1916 break; 1917 } 1918 if (i == imo->imo_num_memberships) { 1919 error = EADDRNOTAVAIL; 1920 goto out; 1921 } 1922 1923 /* 1924 * Give up the multicast address record to which the 1925 * membership points. 1926 */ 1927 in_delmulti(imo->imo_membership[i]); 1928 1929 /* 1930 * Remove the gap in the membership array. 1931 */ 1932 for (++i; i < imo->imo_num_memberships; ++i) 1933 imo->imo_membership[i-1] = imo->imo_membership[i]; 1934 --imo->imo_num_memberships; 1935 error = 0; 1936 out: 1937 if_put(ifp, &psref); 1938 curlwp_bindx(bound); 1939 return error; 1940 } 1941 1942 /* 1943 * Set the IP multicast options in response to user setsockopt(). 1944 */ 1945 int 1946 ip_setmoptions(struct ip_moptions **pimo, const struct sockopt *sopt) 1947 { 1948 struct ip_moptions *imo = *pimo; 1949 struct in_addr addr; 1950 struct ifnet *ifp; 1951 int ifindex, error = 0; 1952 1953 /* The passed imo isn't NULL, it should be protected by solock */ 1954 1955 if (!imo) { 1956 /* 1957 * No multicast option buffer attached to the pcb; 1958 * allocate one and initialize to default values. 1959 */ 1960 imo = kmem_intr_alloc(sizeof(*imo), KM_NOSLEEP); 1961 if (imo == NULL) 1962 return ENOBUFS; 1963 1964 imo->imo_multicast_if_index = 0; 1965 imo->imo_multicast_addr.s_addr = INADDR_ANY; 1966 imo->imo_multicast_ttl = IP_DEFAULT_MULTICAST_TTL; 1967 imo->imo_multicast_loop = IP_DEFAULT_MULTICAST_LOOP; 1968 imo->imo_num_memberships = 0; 1969 *pimo = imo; 1970 } 1971 1972 switch (sopt->sopt_name) { 1973 case IP_MULTICAST_IF: { 1974 int s; 1975 /* 1976 * Select the interface for outgoing multicast packets. 1977 */ 1978 error = sockopt_get(sopt, &addr, sizeof(addr)); 1979 if (error) 1980 break; 1981 1982 /* 1983 * INADDR_ANY is used to remove a previous selection. 1984 * When no interface is selected, a default one is 1985 * chosen every time a multicast packet is sent. 1986 */ 1987 if (in_nullhost(addr)) { 1988 imo->imo_multicast_if_index = 0; 1989 break; 1990 } 1991 /* 1992 * The selected interface is identified by its local 1993 * IP address. Find the interface and confirm that 1994 * it supports multicasting. 1995 */ 1996 s = pserialize_read_enter(); 1997 ifp = ip_multicast_if(&addr, &ifindex); 1998 if (ifp == NULL || (ifp->if_flags & IFF_MULTICAST) == 0) { 1999 pserialize_read_exit(s); 2000 error = EADDRNOTAVAIL; 2001 break; 2002 } 2003 imo->imo_multicast_if_index = ifp->if_index; 2004 pserialize_read_exit(s); 2005 if (ifindex) 2006 imo->imo_multicast_addr = addr; 2007 else 2008 imo->imo_multicast_addr.s_addr = INADDR_ANY; 2009 break; 2010 } 2011 2012 case IP_MULTICAST_TTL: 2013 /* 2014 * Set the IP time-to-live for outgoing multicast packets. 2015 */ 2016 error = ip_getoptval(sopt, &imo->imo_multicast_ttl, MAXTTL); 2017 break; 2018 2019 case IP_MULTICAST_LOOP: 2020 /* 2021 * Set the loopback flag for outgoing multicast packets. 2022 * Must be zero or one. 2023 */ 2024 error = ip_getoptval(sopt, &imo->imo_multicast_loop, 1); 2025 break; 2026 2027 case IP_ADD_MEMBERSHIP: /* IPV6_JOIN_GROUP */ 2028 error = ip_add_membership(imo, sopt); 2029 break; 2030 2031 case IP_DROP_MEMBERSHIP: /* IPV6_LEAVE_GROUP */ 2032 error = ip_drop_membership(imo, sopt); 2033 break; 2034 2035 default: 2036 error = EOPNOTSUPP; 2037 break; 2038 } 2039 2040 /* 2041 * If all options have default values, no need to keep the mbuf. 2042 */ 2043 if (imo->imo_multicast_if_index == 0 && 2044 imo->imo_multicast_ttl == IP_DEFAULT_MULTICAST_TTL && 2045 imo->imo_multicast_loop == IP_DEFAULT_MULTICAST_LOOP && 2046 imo->imo_num_memberships == 0) { 2047 kmem_intr_free(imo, sizeof(*imo)); 2048 *pimo = NULL; 2049 } 2050 2051 return error; 2052 } 2053 2054 /* 2055 * Return the IP multicast options in response to user getsockopt(). 2056 */ 2057 int 2058 ip_getmoptions(struct ip_moptions *imo, struct sockopt *sopt) 2059 { 2060 struct in_addr addr; 2061 uint8_t optval; 2062 int error = 0; 2063 2064 /* imo is protected by solock or referenced only by the caller */ 2065 2066 switch (sopt->sopt_name) { 2067 case IP_MULTICAST_IF: 2068 if (imo == NULL || imo->imo_multicast_if_index == 0) 2069 addr = zeroin_addr; 2070 else if (imo->imo_multicast_addr.s_addr) { 2071 /* return the value user has set */ 2072 addr = imo->imo_multicast_addr; 2073 } else { 2074 struct ifnet *ifp; 2075 struct in_ifaddr *ia = NULL; 2076 int s = pserialize_read_enter(); 2077 2078 ifp = if_byindex(imo->imo_multicast_if_index); 2079 if (ifp != NULL) { 2080 ia = in_get_ia_from_ifp(ifp); 2081 } 2082 addr = ia ? ia->ia_addr.sin_addr : zeroin_addr; 2083 pserialize_read_exit(s); 2084 } 2085 error = sockopt_set(sopt, &addr, sizeof(addr)); 2086 break; 2087 2088 case IP_MULTICAST_TTL: 2089 optval = imo ? imo->imo_multicast_ttl 2090 : IP_DEFAULT_MULTICAST_TTL; 2091 2092 error = sockopt_set(sopt, &optval, sizeof(optval)); 2093 break; 2094 2095 case IP_MULTICAST_LOOP: 2096 optval = imo ? imo->imo_multicast_loop 2097 : IP_DEFAULT_MULTICAST_LOOP; 2098 2099 error = sockopt_set(sopt, &optval, sizeof(optval)); 2100 break; 2101 2102 default: 2103 error = EOPNOTSUPP; 2104 } 2105 2106 return error; 2107 } 2108 2109 /* 2110 * Discard the IP multicast options. 2111 */ 2112 void 2113 ip_freemoptions(struct ip_moptions *imo) 2114 { 2115 int i; 2116 2117 /* The owner of imo (inp) should be protected by solock */ 2118 2119 if (imo != NULL) { 2120 for (i = 0; i < imo->imo_num_memberships; ++i) { 2121 struct in_multi *inm = imo->imo_membership[i]; 2122 in_delmulti(inm); 2123 /* ifp should not leave thanks to solock */ 2124 } 2125 2126 kmem_intr_free(imo, sizeof(*imo)); 2127 } 2128 } 2129 2130 /* 2131 * Routine called from ip_output() to loop back a copy of an IP multicast 2132 * packet to the input queue of a specified interface. Note that this 2133 * calls the output routine of the loopback "driver", but with an interface 2134 * pointer that might NOT be lo0ifp -- easier than replicating that code here. 2135 */ 2136 static void 2137 ip_mloopback(struct ifnet *ifp, struct mbuf *m, const struct sockaddr_in *dst) 2138 { 2139 struct ip *ip; 2140 struct mbuf *copym; 2141 2142 copym = m_copypacket(m, M_DONTWAIT); 2143 if (copym != NULL && 2144 (copym->m_flags & M_EXT || copym->m_len < sizeof(struct ip))) 2145 copym = m_pullup(copym, sizeof(struct ip)); 2146 if (copym == NULL) 2147 return; 2148 /* 2149 * We don't bother to fragment if the IP length is greater 2150 * than the interface's MTU. Can this possibly matter? 2151 */ 2152 ip = mtod(copym, struct ip *); 2153 2154 if (copym->m_pkthdr.csum_flags & (M_CSUM_TCPv4|M_CSUM_UDPv4)) { 2155 in_undefer_cksum_tcpudp(copym); 2156 copym->m_pkthdr.csum_flags &= 2157 ~(M_CSUM_TCPv4|M_CSUM_UDPv4); 2158 } 2159 2160 ip->ip_sum = 0; 2161 ip->ip_sum = in_cksum(copym, ip->ip_hl << 2); 2162 KERNEL_LOCK_UNLESS_NET_MPSAFE(); 2163 (void)looutput(ifp, copym, sintocsa(dst), NULL); 2164 KERNEL_UNLOCK_UNLESS_NET_MPSAFE(); 2165 } 2166 2167 /* 2168 * Ensure sending address is valid. 2169 * Returns 0 on success, -1 if an error should be sent back or 1 2170 * if the packet could be dropped without error (protocol dependent). 2171 */ 2172 static int 2173 ip_ifaddrvalid(const struct in_ifaddr *ia) 2174 { 2175 2176 if (ia->ia_addr.sin_addr.s_addr == INADDR_ANY) 2177 return 0; 2178 2179 if (ia->ia4_flags & IN_IFF_DUPLICATED) 2180 return -1; 2181 else if (ia->ia4_flags & (IN_IFF_TENTATIVE | IN_IFF_DETACHED)) 2182 return 1; 2183 2184 return 0; 2185 } 2186
Indexes created Wed Oct 01 12:09:54 GMT 2025