1 /* 2 * Copyright (c) 1982, 1986, 1988, 1990, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * @(#)ip_output.c 8.3 (Berkeley) 1/21/94 34 * $FreeBSD$ 35 */ 36 37 #define _IP_VHL 38 39 #include "opt_ipfw.h" 40 #include "opt_ipdn.h" 41 #include "opt_ipdivert.h" 42 #include "opt_ipfilter.h" 43 #include "opt_ipsec.h" 44 #include "opt_pfil_hooks.h" 45 #include "opt_random_ip_id.h" 46 47 #include <sys/param.h> 48 #include <sys/systm.h> 49 #include <sys/kernel.h> 50 #include <sys/malloc.h> 51 #include <sys/mbuf.h> 52 #include <sys/protosw.h> 53 #include <sys/socket.h> 54 #include <sys/socketvar.h> 55 56 #include <net/if.h> 57 #include <net/route.h> 58 59 #include <netinet/in.h> 60 #include <netinet/in_systm.h> 61 #include <netinet/ip.h> 62 #include <netinet/in_pcb.h> 63 #include <netinet/in_var.h> 64 #include <netinet/ip_var.h> 65 66 #include "faith.h" 67 68 #include <machine/in_cksum.h> 69 70 static MALLOC_DEFINE(M_IPMOPTS, "ip_moptions", "internet multicast options"); 71 72 #ifdef IPSEC 73 #include <netinet6/ipsec.h> 74 #include <netkey/key.h> 75 #ifdef IPSEC_DEBUG 76 #include <netkey/key_debug.h> 77 #else 78 #define KEYDEBUG(lev,arg) 79 #endif 80 #endif /*IPSEC*/ 81 82 #include <netinet/ip_fw.h> 83 84 #ifdef DUMMYNET 85 #include <netinet/ip_dummynet.h> 86 #endif 87 88 #ifdef IPFIREWALL_FORWARD_DEBUG 89 #define print_ip(a) printf("%ld.%ld.%ld.%ld",(ntohl(a.s_addr)>>24)&0xFF,\ 90 (ntohl(a.s_addr)>>16)&0xFF,\ 91 (ntohl(a.s_addr)>>8)&0xFF,\ 92 (ntohl(a.s_addr))&0xFF); 93 #endif 94 95 u_short ip_id; 96 97 static struct mbuf *ip_insertoptions __P((struct mbuf *, struct mbuf *, int *)); 98 static struct ifnet *ip_multicast_if __P((struct in_addr *, int *)); 99 static void ip_mloopback 100 __P((struct ifnet *, struct mbuf *, struct sockaddr_in *, int)); 101 static int ip_getmoptions 102 __P((struct sockopt *, struct ip_moptions *)); 103 static int ip_pcbopts __P((int, struct mbuf **, struct mbuf *)); 104 static int ip_setmoptions 105 __P((struct sockopt *, struct ip_moptions **)); 106 107 int ip_optcopy __P((struct ip *, struct ip *)); 108 109 110 extern struct protosw inetsw[]; 111 112 /* 113 * IP output. The packet in mbuf chain m contains a skeletal IP 114 * header (with len, off, ttl, proto, tos, src, dst). 115 * The mbuf chain containing the packet will be freed. 116 * The mbuf opt, if present, will not be freed. 117 */ 118 int 119 ip_output(m0, opt, ro, flags, imo) 120 struct mbuf *m0; 121 struct mbuf *opt; 122 struct route *ro; 123 int flags; 124 struct ip_moptions *imo; 125 { 126 struct ip *ip, *mhip; 127 struct ifnet *ifp; 128 struct mbuf *m = m0; 129 int hlen = sizeof (struct ip); 130 int len, off, error = 0; 131 struct sockaddr_in *dst; 132 struct in_ifaddr *ia; 133 int isbroadcast, sw_csum; 134 #ifdef IPSEC 135 struct route iproute; 136 struct socket *so = NULL; 137 struct secpolicy *sp = NULL; 138 #endif 139 u_int16_t divert_cookie; /* firewall cookie */ 140 #ifdef PFIL_HOOKS 141 struct packet_filter_hook *pfh; 142 struct mbuf *m1; 143 int rv; 144 #endif /* PFIL_HOOKS */ 145 #ifdef IPFIREWALL_FORWARD 146 int fwd_rewrite_src = 0; 147 #endif 148 struct ip_fw_chain *rule = NULL; 149 150 #ifdef IPDIVERT 151 /* Get and reset firewall cookie */ 152 divert_cookie = ip_divert_cookie; 153 ip_divert_cookie = 0; 154 #else 155 divert_cookie = 0; 156 #endif 157 158 #if defined(IPFIREWALL) && defined(DUMMYNET) 159 /* 160 * dummynet packet are prepended a vestigial mbuf with 161 * m_type = MT_DUMMYNET and m_data pointing to the matching 162 * rule. 163 */ 164 if (m->m_type == MT_DUMMYNET) { 165 /* 166 * the packet was already tagged, so part of the 167 * processing was already done, and we need to go down. 168 * Get parameters from the header. 169 */ 170 rule = (struct ip_fw_chain *)(m->m_data) ; 171 opt = NULL ; 172 ro = & ( ((struct dn_pkt *)m)->ro ) ; 173 imo = NULL ; 174 dst = ((struct dn_pkt *)m)->dn_dst ; 175 ifp = ((struct dn_pkt *)m)->ifp ; 176 flags = ((struct dn_pkt *)m)->flags ; 177 178 m0 = m = m->m_next ; 179 #ifdef IPSEC 180 so = ipsec_getsocket(m); 181 (void)ipsec_setsocket(m, NULL); 182 #endif 183 ip = mtod(m, struct ip *); 184 hlen = IP_VHL_HL(ip->ip_vhl) << 2 ; 185 ia = (struct in_ifaddr *)ro->ro_rt->rt_ifa; 186 goto sendit; 187 } else 188 rule = NULL ; 189 #endif 190 #ifdef IPSEC 191 so = ipsec_getsocket(m); 192 (void)ipsec_setsocket(m, NULL); 193 #endif 194 195 #ifdef DIAGNOSTIC 196 if ((m->m_flags & M_PKTHDR) == 0) 197 panic("ip_output no HDR"); 198 if (!ro) 199 panic("ip_output no route, proto = %d", 200 mtod(m, struct ip *)->ip_p); 201 #endif 202 if (opt) { 203 m = ip_insertoptions(m, opt, &len); 204 hlen = len; 205 } 206 ip = mtod(m, struct ip *); 207 /* 208 * Fill in IP header. 209 */ 210 if ((flags & (IP_FORWARDING|IP_RAWOUTPUT)) == 0) { 211 ip->ip_vhl = IP_MAKE_VHL(IPVERSION, hlen >> 2); 212 ip->ip_off &= IP_DF; 213 #ifdef RANDOM_IP_ID 214 ip->ip_id = ip_randomid(); 215 #else 216 ip->ip_id = htons(ip_id++); 217 #endif 218 ipstat.ips_localout++; 219 } else { 220 hlen = IP_VHL_HL(ip->ip_vhl) << 2; 221 } 222 223 dst = (struct sockaddr_in *)&ro->ro_dst; 224 /* 225 * If there is a cached route, 226 * check that it is to the same destination 227 * and is still up. If not, free it and try again. 228 */ 229 if (ro->ro_rt && ((ro->ro_rt->rt_flags & RTF_UP) == 0 || 230 dst->sin_addr.s_addr != ip->ip_dst.s_addr)) { 231 RTFREE(ro->ro_rt); 232 ro->ro_rt = (struct rtentry *)0; 233 } 234 if (ro->ro_rt == 0) { 235 dst->sin_family = AF_INET; 236 dst->sin_len = sizeof(*dst); 237 dst->sin_addr = ip->ip_dst; 238 } 239 /* 240 * If routing to interface only, 241 * short circuit routing lookup. 242 */ 243 #define ifatoia(ifa) ((struct in_ifaddr *)(ifa)) 244 #define sintosa(sin) ((struct sockaddr *)(sin)) 245 if (flags & IP_ROUTETOIF) { 246 if ((ia = ifatoia(ifa_ifwithdstaddr(sintosa(dst)))) == 0 && 247 (ia = ifatoia(ifa_ifwithnet(sintosa(dst)))) == 0) { 248 ipstat.ips_noroute++; 249 error = ENETUNREACH; 250 goto bad; 251 } 252 ifp = ia->ia_ifp; 253 ip->ip_ttl = 1; 254 isbroadcast = in_broadcast(dst->sin_addr, ifp); 255 } else if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) && 256 imo != NULL && imo->imo_multicast_ifp != NULL) { 257 /* 258 * Bypass the normal routing lookup for multicast 259 * packets if the interface is specified. 260 */ 261 ifp = imo->imo_multicast_ifp; 262 IFP_TO_IA(ifp, ia); 263 isbroadcast = 0; /* fool gcc */ 264 } else { 265 /* 266 * If this is the case, we probably don't want to allocate 267 * a protocol-cloned route since we didn't get one from the 268 * ULP. This lets TCP do its thing, while not burdening 269 * forwarding or ICMP with the overhead of cloning a route. 270 * Of course, we still want to do any cloning requested by 271 * the link layer, as this is probably required in all cases 272 * for correct operation (as it is for ARP). 273 */ 274 if (ro->ro_rt == 0) 275 rtalloc_ign(ro, RTF_PRCLONING); 276 if (ro->ro_rt == 0) { 277 ipstat.ips_noroute++; 278 error = EHOSTUNREACH; 279 goto bad; 280 } 281 ia = ifatoia(ro->ro_rt->rt_ifa); 282 ifp = ro->ro_rt->rt_ifp; 283 ro->ro_rt->rt_use++; 284 if (ro->ro_rt->rt_flags & RTF_GATEWAY) 285 dst = (struct sockaddr_in *)ro->ro_rt->rt_gateway; 286 if (ro->ro_rt->rt_flags & RTF_HOST) 287 isbroadcast = (ro->ro_rt->rt_flags & RTF_BROADCAST); 288 else 289 isbroadcast = in_broadcast(dst->sin_addr, ifp); 290 } 291 if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr))) { 292 struct in_multi *inm; 293 294 m->m_flags |= M_MCAST; 295 /* 296 * IP destination address is multicast. Make sure "dst" 297 * still points to the address in "ro". (It may have been 298 * changed to point to a gateway address, above.) 299 */ 300 dst = (struct sockaddr_in *)&ro->ro_dst; 301 /* 302 * See if the caller provided any multicast options 303 */ 304 if (imo != NULL) { 305 ip->ip_ttl = imo->imo_multicast_ttl; 306 if (imo->imo_multicast_vif != -1) 307 ip->ip_src.s_addr = 308 ip_mcast_src(imo->imo_multicast_vif); 309 } else 310 ip->ip_ttl = IP_DEFAULT_MULTICAST_TTL; 311 /* 312 * Confirm that the outgoing interface supports multicast. 313 */ 314 if ((imo == NULL) || (imo->imo_multicast_vif == -1)) { 315 if ((ifp->if_flags & IFF_MULTICAST) == 0) { 316 ipstat.ips_noroute++; 317 error = ENETUNREACH; 318 goto bad; 319 } 320 } 321 /* 322 * If source address not specified yet, use address 323 * of outgoing interface. 324 */ 325 if (ip->ip_src.s_addr == INADDR_ANY) { 326 /* Interface may have no addresses. */ 327 if (ia != NULL) 328 ip->ip_src = IA_SIN(ia)->sin_addr; 329 } 330 331 IN_LOOKUP_MULTI(ip->ip_dst, ifp, inm); 332 if (inm != NULL && 333 (imo == NULL || imo->imo_multicast_loop)) { 334 /* 335 * If we belong to the destination multicast group 336 * on the outgoing interface, and the caller did not 337 * forbid loopback, loop back a copy. 338 */ 339 ip_mloopback(ifp, m, dst, hlen); 340 } 341 else { 342 /* 343 * If we are acting as a multicast router, perform 344 * multicast forwarding as if the packet had just 345 * arrived on the interface to which we are about 346 * to send. The multicast forwarding function 347 * recursively calls this function, using the 348 * IP_FORWARDING flag to prevent infinite recursion. 349 * 350 * Multicasts that are looped back by ip_mloopback(), 351 * above, will be forwarded by the ip_input() routine, 352 * if necessary. 353 */ 354 if (ip_mrouter && (flags & IP_FORWARDING) == 0) { 355 /* 356 * Check if rsvp daemon is running. If not, don't 357 * set ip_moptions. This ensures that the packet 358 * is multicast and not just sent down one link 359 * as prescribed by rsvpd. 360 */ 361 if (!rsvp_on) 362 imo = NULL; 363 if (ip_mforward(ip, ifp, m, imo) != 0) { 364 m_freem(m); 365 goto done; 366 } 367 } 368 } 369 370 /* 371 * Multicasts with a time-to-live of zero may be looped- 372 * back, above, but must not be transmitted on a network. 373 * Also, multicasts addressed to the loopback interface 374 * are not sent -- the above call to ip_mloopback() will 375 * loop back a copy if this host actually belongs to the 376 * destination group on the loopback interface. 377 */ 378 if (ip->ip_ttl == 0 || ifp->if_flags & IFF_LOOPBACK) { 379 m_freem(m); 380 goto done; 381 } 382 383 goto sendit; 384 } 385 #ifndef notdef 386 /* 387 * If source address not specified yet, use address 388 * of outgoing interface. 389 */ 390 if (ip->ip_src.s_addr == INADDR_ANY) { 391 /* Interface may have no addresses. */ 392 if (ia != NULL) { 393 ip->ip_src = IA_SIN(ia)->sin_addr; 394 #ifdef IPFIREWALL_FORWARD 395 /* Keep note that we did this - if the firewall changes 396 * the next-hop, our interface may change, changing the 397 * default source IP. It's a shame so much effort happens 398 * twice. Oh well. 399 */ 400 fwd_rewrite_src++; 401 #endif /* IPFIREWALL_FORWARD */ 402 } 403 } 404 #endif /* notdef */ 405 /* 406 * Verify that we have any chance at all of being able to queue 407 * the packet or packet fragments 408 */ 409 if ((ifp->if_snd.ifq_len + ip->ip_len / ifp->if_mtu + 1) >= 410 ifp->if_snd.ifq_maxlen) { 411 error = ENOBUFS; 412 goto bad; 413 } 414 415 /* 416 * Look for broadcast address and 417 * and verify user is allowed to send 418 * such a packet. 419 */ 420 if (isbroadcast) { 421 if ((ifp->if_flags & IFF_BROADCAST) == 0) { 422 error = EADDRNOTAVAIL; 423 goto bad; 424 } 425 if ((flags & IP_ALLOWBROADCAST) == 0) { 426 error = EACCES; 427 goto bad; 428 } 429 /* don't allow broadcast messages to be fragmented */ 430 if ((u_short)ip->ip_len > ifp->if_mtu) { 431 error = EMSGSIZE; 432 goto bad; 433 } 434 m->m_flags |= M_BCAST; 435 } else { 436 m->m_flags &= ~M_BCAST; 437 } 438 439 sendit: 440 #ifdef IPSEC 441 /* get SP for this packet */ 442 if (so == NULL) 443 sp = ipsec4_getpolicybyaddr(m, IPSEC_DIR_OUTBOUND, flags, &error); 444 else 445 sp = ipsec4_getpolicybysock(m, IPSEC_DIR_OUTBOUND, so, &error); 446 447 if (sp == NULL) { 448 ipsecstat.out_inval++; 449 goto bad; 450 } 451 452 error = 0; 453 454 /* check policy */ 455 switch (sp->policy) { 456 case IPSEC_POLICY_DISCARD: 457 /* 458 * This packet is just discarded. 459 */ 460 ipsecstat.out_polvio++; 461 goto bad; 462 463 case IPSEC_POLICY_BYPASS: 464 case IPSEC_POLICY_NONE: 465 /* no need to do IPsec. */ 466 goto skip_ipsec; 467 468 case IPSEC_POLICY_IPSEC: 469 if (sp->req == NULL) { 470 /* acquire a policy */ 471 error = key_spdacquire(sp); 472 goto bad; 473 } 474 break; 475 476 case IPSEC_POLICY_ENTRUST: 477 default: 478 printf("ip_output: Invalid policy found. %d\n", sp->policy); 479 } 480 { 481 struct ipsec_output_state state; 482 bzero(&state, sizeof(state)); 483 state.m = m; 484 if (flags & IP_ROUTETOIF) { 485 state.ro = &iproute; 486 bzero(&iproute, sizeof(iproute)); 487 } else 488 state.ro = ro; 489 state.dst = (struct sockaddr *)dst; 490 491 ip->ip_sum = 0; 492 493 /* 494 * XXX 495 * delayed checksums are not currently compatible with IPsec 496 */ 497 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) { 498 in_delayed_cksum(m); 499 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA; 500 } 501 502 HTONS(ip->ip_len); 503 HTONS(ip->ip_off); 504 505 error = ipsec4_output(&state, sp, flags); 506 507 m = state.m; 508 if (flags & IP_ROUTETOIF) { 509 /* 510 * if we have tunnel mode SA, we may need to ignore 511 * IP_ROUTETOIF. 512 */ 513 if (state.ro != &iproute || state.ro->ro_rt != NULL) { 514 flags &= ~IP_ROUTETOIF; 515 ro = state.ro; 516 } 517 } else 518 ro = state.ro; 519 dst = (struct sockaddr_in *)state.dst; 520 if (error) { 521 /* mbuf is already reclaimed in ipsec4_output. */ 522 m0 = NULL; 523 switch (error) { 524 case EHOSTUNREACH: 525 case ENETUNREACH: 526 case EMSGSIZE: 527 case ENOBUFS: 528 case ENOMEM: 529 break; 530 default: 531 printf("ip4_output (ipsec): error code %d\n", error); 532 /*fall through*/ 533 case ENOENT: 534 /* don't show these error codes to the user */ 535 error = 0; 536 break; 537 } 538 goto bad; 539 } 540 } 541 542 /* be sure to update variables that are affected by ipsec4_output() */ 543 ip = mtod(m, struct ip *); 544 #ifdef _IP_VHL 545 hlen = IP_VHL_HL(ip->ip_vhl) << 2; 546 #else 547 hlen = ip->ip_hl << 2; 548 #endif 549 if (ro->ro_rt == NULL) { 550 if ((flags & IP_ROUTETOIF) == 0) { 551 printf("ip_output: " 552 "can't update route after IPsec processing\n"); 553 error = EHOSTUNREACH; /*XXX*/ 554 goto bad; 555 } 556 } else { 557 ia = ifatoia(ro->ro_rt->rt_ifa); 558 ifp = ro->ro_rt->rt_ifp; 559 } 560 561 /* make it flipped, again. */ 562 NTOHS(ip->ip_len); 563 NTOHS(ip->ip_off); 564 skip_ipsec: 565 #endif /*IPSEC*/ 566 567 /* 568 * IpHack's section. 569 * - Xlate: translate packet's addr/port (NAT). 570 * - Firewall: deny/allow/etc. 571 * - Wrap: fake packet's addr/port <unimpl.> 572 * - Encapsulate: put it in another IP and send out. <unimp.> 573 */ 574 #ifdef PFIL_HOOKS 575 /* 576 * Run through list of hooks for output packets. 577 */ 578 m1 = m; 579 pfh = pfil_hook_get(PFIL_OUT, &inetsw[ip_protox[IPPROTO_IP]].pr_pfh); 580 for (; pfh; pfh = TAILQ_NEXT(pfh, pfil_link)) 581 if (pfh->pfil_func) { 582 rv = pfh->pfil_func(ip, hlen, ifp, 1, &m1); 583 if (rv) { 584 error = EHOSTUNREACH; 585 goto done; 586 } 587 m = m1; 588 if (m == NULL) 589 goto done; 590 ip = mtod(m, struct ip *); 591 } 592 #endif /* PFIL_HOOKS */ 593 594 /* 595 * Check with the firewall... 596 */ 597 if (fw_enable && ip_fw_chk_ptr) { 598 struct sockaddr_in *old = dst; 599 600 off = (*ip_fw_chk_ptr)(&ip, 601 hlen, ifp, &divert_cookie, &m, &rule, &dst); 602 /* 603 * On return we must do the following: 604 * m == NULL -> drop the pkt (old interface, deprecated) 605 * (off & 0x40000) -> drop the pkt (new interface) 606 * 1<=off<= 0xffff -> DIVERT 607 * (off & 0x10000) -> send to a DUMMYNET pipe 608 * (off & 0x20000) -> TEE the packet 609 * dst != old -> IPFIREWALL_FORWARD 610 * off==0, dst==old -> accept 611 * If some of the above modules is not compiled in, then 612 * we should't have to check the corresponding condition 613 * (because the ipfw control socket should not accept 614 * unsupported rules), but better play safe and drop 615 * packets in case of doubt. 616 */ 617 if (off & IP_FW_PORT_DENY_FLAG) { /* XXX new interface-denied */ 618 if (m) 619 m_freem(m); 620 error = EACCES ; 621 goto done; 622 } 623 if (!m) { /* firewall said to reject */ 624 static int __debug=10; 625 if (__debug >0) { 626 printf("firewall returns NULL, please update!\n"); 627 __debug-- ; 628 } 629 error = EACCES; 630 goto done; 631 } 632 if (off == 0 && dst == old) /* common case */ 633 goto pass ; 634 #ifdef DUMMYNET 635 if ((off & IP_FW_PORT_DYNT_FLAG) != 0) { 636 /* 637 * pass the pkt to dummynet. Need to include 638 * pipe number, m, ifp, ro, dst because these are 639 * not recomputed in the next pass. 640 * All other parameters have been already used and 641 * so they are not needed anymore. 642 * XXX note: if the ifp or ro entry are deleted 643 * while a pkt is in dummynet, we are in trouble! 644 */ 645 error = dummynet_io(off & 0xffff, DN_TO_IP_OUT, m, 646 ifp,ro,dst,rule, flags); 647 goto done; 648 } 649 #endif 650 #ifdef IPDIVERT 651 if (off != 0 && (off & IP_FW_PORT_DYNT_FLAG) == 0) { 652 struct mbuf *clone = NULL; 653 654 /* Clone packet if we're doing a 'tee' */ 655 if ((off & IP_FW_PORT_TEE_FLAG) != 0) 656 clone = m_dup(m, M_DONTWAIT); 657 658 /* 659 * XXX 660 * delayed checksums are not currently compatible 661 * with divert sockets. 662 */ 663 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) { 664 in_delayed_cksum(m); 665 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA; 666 } 667 668 /* Restore packet header fields to original values */ 669 HTONS(ip->ip_len); 670 HTONS(ip->ip_off); 671 672 /* Deliver packet to divert input routine */ 673 ip_divert_cookie = divert_cookie; 674 divert_packet(m, 0, off & 0xffff); 675 676 /* If 'tee', continue with original packet */ 677 if (clone != NULL) { 678 m = clone; 679 ip = mtod(m, struct ip *); 680 goto pass; 681 } 682 goto done; 683 } 684 #endif 685 686 #ifdef IPFIREWALL_FORWARD 687 /* Here we check dst to make sure it's directly reachable on the 688 * interface we previously thought it was. 689 * If it isn't (which may be likely in some situations) we have 690 * to re-route it (ie, find a route for the next-hop and the 691 * associated interface) and set them here. This is nested 692 * forwarding which in most cases is undesirable, except where 693 * such control is nigh impossible. So we do it here. 694 * And I'm babbling. 695 */ 696 if (off == 0 && old != dst) { 697 struct in_ifaddr *ia; 698 699 /* It's changed... */ 700 /* There must be a better way to do this next line... */ 701 static struct route sro_fwd, *ro_fwd = &sro_fwd; 702 #ifdef IPFIREWALL_FORWARD_DEBUG 703 printf("IPFIREWALL_FORWARD: New dst ip: "); 704 print_ip(dst->sin_addr); 705 printf("\n"); 706 #endif 707 /* 708 * We need to figure out if we have been forwarded 709 * to a local socket. If so then we should somehow 710 * "loop back" to ip_input, and get directed to the 711 * PCB as if we had received this packet. This is 712 * because it may be dificult to identify the packets 713 * you want to forward until they are being output 714 * and have selected an interface. (e.g. locally 715 * initiated packets) If we used the loopback inteface, 716 * we would not be able to control what happens 717 * as the packet runs through ip_input() as 718 * it is done through a ISR. 719 */ 720 TAILQ_FOREACH(ia, &in_ifaddrhead, ia_link) { 721 /* 722 * If the addr to forward to is one 723 * of ours, we pretend to 724 * be the destination for this packet. 725 */ 726 if (IA_SIN(ia)->sin_addr.s_addr == 727 dst->sin_addr.s_addr) 728 break; 729 } 730 if (ia) { 731 /* tell ip_input "dont filter" */ 732 ip_fw_fwd_addr = dst; 733 if (m->m_pkthdr.rcvif == NULL) 734 m->m_pkthdr.rcvif = ifunit("lo0"); 735 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) { 736 m->m_pkthdr.csum_flags |= 737 CSUM_DATA_VALID | CSUM_PSEUDO_HDR; 738 m0->m_pkthdr.csum_data = 0xffff; 739 } 740 m->m_pkthdr.csum_flags |= 741 CSUM_IP_CHECKED | CSUM_IP_VALID; 742 HTONS(ip->ip_len); 743 HTONS(ip->ip_off); 744 ip_input(m); 745 goto done; 746 } 747 /* Some of the logic for this was 748 * nicked from above. 749 * 750 * This rewrites the cached route in a local PCB. 751 * Is this what we want to do? 752 */ 753 bcopy(dst, &ro_fwd->ro_dst, sizeof(*dst)); 754 755 ro_fwd->ro_rt = 0; 756 rtalloc_ign(ro_fwd, RTF_PRCLONING); 757 758 if (ro_fwd->ro_rt == 0) { 759 ipstat.ips_noroute++; 760 error = EHOSTUNREACH; 761 goto bad; 762 } 763 764 ia = ifatoia(ro_fwd->ro_rt->rt_ifa); 765 ifp = ro_fwd->ro_rt->rt_ifp; 766 ro_fwd->ro_rt->rt_use++; 767 if (ro_fwd->ro_rt->rt_flags & RTF_GATEWAY) 768 dst = (struct sockaddr_in *)ro_fwd->ro_rt->rt_gateway; 769 if (ro_fwd->ro_rt->rt_flags & RTF_HOST) 770 isbroadcast = 771 (ro_fwd->ro_rt->rt_flags & RTF_BROADCAST); 772 else 773 isbroadcast = in_broadcast(dst->sin_addr, ifp); 774 RTFREE(ro->ro_rt); 775 ro->ro_rt = ro_fwd->ro_rt; 776 dst = (struct sockaddr_in *)&ro_fwd->ro_dst; 777 778 /* 779 * If we added a default src ip earlier, 780 * which would have been gotten from the-then 781 * interface, do it again, from the new one. 782 */ 783 if (fwd_rewrite_src) 784 ip->ip_src = IA_SIN(ia)->sin_addr; 785 goto pass ; 786 } 787 #endif /* IPFIREWALL_FORWARD */ 788 /* 789 * if we get here, none of the above matches, and 790 * we have to drop the pkt 791 */ 792 m_freem(m); 793 error = EACCES; /* not sure this is the right error msg */ 794 goto done; 795 } 796 797 pass: 798 m->m_pkthdr.csum_flags |= CSUM_IP; 799 sw_csum = m->m_pkthdr.csum_flags & ~ifp->if_hwassist; 800 if (sw_csum & CSUM_DELAY_DATA) { 801 in_delayed_cksum(m); 802 sw_csum &= ~CSUM_DELAY_DATA; 803 } 804 m->m_pkthdr.csum_flags &= ifp->if_hwassist; 805 806 /* 807 * If small enough for interface, or the interface will take 808 * care of the fragmentation for us, can just send directly. 809 */ 810 if ((u_short)ip->ip_len <= ifp->if_mtu || 811 ifp->if_hwassist & CSUM_FRAGMENT) { 812 HTONS(ip->ip_len); 813 HTONS(ip->ip_off); 814 ip->ip_sum = 0; 815 if (sw_csum & CSUM_DELAY_IP) { 816 if (ip->ip_vhl == IP_VHL_BORING) { 817 ip->ip_sum = in_cksum_hdr(ip); 818 } else { 819 ip->ip_sum = in_cksum(m, hlen); 820 } 821 } 822 823 /* Record statistics for this interface address. */ 824 if (!(flags & IP_FORWARDING) && ia) { 825 ia->ia_ifa.if_opackets++; 826 ia->ia_ifa.if_obytes += m->m_pkthdr.len; 827 } 828 829 #ifdef IPSEC 830 /* clean ipsec history once it goes out of the node */ 831 ipsec_delaux(m); 832 #endif 833 834 error = (*ifp->if_output)(ifp, m, 835 (struct sockaddr *)dst, ro->ro_rt); 836 goto done; 837 } 838 /* 839 * Too large for interface; fragment if possible. 840 * Must be able to put at least 8 bytes per fragment. 841 */ 842 if (ip->ip_off & IP_DF) { 843 error = EMSGSIZE; 844 /* 845 * This case can happen if the user changed the MTU 846 * of an interface after enabling IP on it. Because 847 * most netifs don't keep track of routes pointing to 848 * them, there is no way for one to update all its 849 * routes when the MTU is changed. 850 */ 851 if ((ro->ro_rt->rt_flags & (RTF_UP | RTF_HOST)) 852 && !(ro->ro_rt->rt_rmx.rmx_locks & RTV_MTU) 853 && (ro->ro_rt->rt_rmx.rmx_mtu > ifp->if_mtu)) { 854 ro->ro_rt->rt_rmx.rmx_mtu = ifp->if_mtu; 855 } 856 ipstat.ips_cantfrag++; 857 goto bad; 858 } 859 len = (ifp->if_mtu - hlen) &~ 7; 860 if (len < 8) { 861 error = EMSGSIZE; 862 goto bad; 863 } 864 865 /* 866 * if the interface will not calculate checksums on 867 * fragmented packets, then do it here. 868 */ 869 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA && 870 (ifp->if_hwassist & CSUM_IP_FRAGS) == 0) { 871 in_delayed_cksum(m); 872 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA; 873 } 874 875 { 876 int mhlen, firstlen = len; 877 struct mbuf **mnext = &m->m_nextpkt; 878 int nfrags = 1; 879 880 /* 881 * Loop through length of segment after first fragment, 882 * make new header and copy data of each part and link onto chain. 883 */ 884 m0 = m; 885 mhlen = sizeof (struct ip); 886 for (off = hlen + len; off < (u_short)ip->ip_len; off += len) { 887 MGETHDR(m, M_DONTWAIT, MT_HEADER); 888 if (m == 0) { 889 error = ENOBUFS; 890 ipstat.ips_odropped++; 891 goto sendorfree; 892 } 893 m->m_flags |= (m0->m_flags & M_MCAST) | M_FRAG; 894 m->m_data += max_linkhdr; 895 mhip = mtod(m, struct ip *); 896 *mhip = *ip; 897 if (hlen > sizeof (struct ip)) { 898 mhlen = ip_optcopy(ip, mhip) + sizeof (struct ip); 899 mhip->ip_vhl = IP_MAKE_VHL(IPVERSION, mhlen >> 2); 900 } 901 m->m_len = mhlen; 902 mhip->ip_off = ((off - hlen) >> 3) + ip->ip_off; 903 if (off + len >= (u_short)ip->ip_len) 904 len = (u_short)ip->ip_len - off; 905 else 906 mhip->ip_off |= IP_MF; 907 mhip->ip_len = htons((u_short)(len + mhlen)); 908 m->m_next = m_copy(m0, off, len); 909 if (m->m_next == 0) { 910 (void) m_free(m); 911 error = ENOBUFS; /* ??? */ 912 ipstat.ips_odropped++; 913 goto sendorfree; 914 } 915 m->m_pkthdr.len = mhlen + len; 916 m->m_pkthdr.rcvif = (struct ifnet *)0; 917 m->m_pkthdr.csum_flags = m0->m_pkthdr.csum_flags; 918 HTONS(mhip->ip_off); 919 mhip->ip_sum = 0; 920 if (sw_csum & CSUM_DELAY_IP) { 921 if (mhip->ip_vhl == IP_VHL_BORING) { 922 mhip->ip_sum = in_cksum_hdr(mhip); 923 } else { 924 mhip->ip_sum = in_cksum(m, mhlen); 925 } 926 } 927 *mnext = m; 928 mnext = &m->m_nextpkt; 929 nfrags++; 930 } 931 ipstat.ips_ofragments += nfrags; 932 933 /* set first/last markers for fragment chain */ 934 m->m_flags |= M_LASTFRAG; 935 m0->m_flags |= M_FIRSTFRAG | M_FRAG; 936 m0->m_pkthdr.csum_data = nfrags; 937 938 /* 939 * Update first fragment by trimming what's been copied out 940 * and updating header, then send each fragment (in order). 941 */ 942 m = m0; 943 m_adj(m, hlen + firstlen - (u_short)ip->ip_len); 944 m->m_pkthdr.len = hlen + firstlen; 945 ip->ip_len = htons((u_short)m->m_pkthdr.len); 946 ip->ip_off |= IP_MF; 947 HTONS(ip->ip_off); 948 ip->ip_sum = 0; 949 if (sw_csum & CSUM_DELAY_IP) { 950 if (ip->ip_vhl == IP_VHL_BORING) { 951 ip->ip_sum = in_cksum_hdr(ip); 952 } else { 953 ip->ip_sum = in_cksum(m, hlen); 954 } 955 } 956 sendorfree: 957 for (m = m0; m; m = m0) { 958 m0 = m->m_nextpkt; 959 m->m_nextpkt = 0; 960 #ifdef IPSEC 961 /* clean ipsec history once it goes out of the node */ 962 ipsec_delaux(m); 963 #endif 964 if (error == 0) { 965 /* Record statistics for this interface address. */ 966 if (ia != NULL) { 967 ia->ia_ifa.if_opackets++; 968 ia->ia_ifa.if_obytes += m->m_pkthdr.len; 969 } 970 971 error = (*ifp->if_output)(ifp, m, 972 (struct sockaddr *)dst, ro->ro_rt); 973 } else 974 m_freem(m); 975 } 976 977 if (error == 0) 978 ipstat.ips_fragmented++; 979 } 980 done: 981 #ifdef IPSEC 982 if (ro == &iproute && ro->ro_rt) { 983 RTFREE(ro->ro_rt); 984 ro->ro_rt = NULL; 985 } 986 if (sp != NULL) { 987 KEYDEBUG(KEYDEBUG_IPSEC_STAMP, 988 printf("DP ip_output call free SP:%p\n", sp)); 989 key_freesp(sp); 990 } 991 #endif /* IPSEC */ 992 return (error); 993 bad: 994 m_freem(m0); 995 goto done; 996 } 997 998 void 999 in_delayed_cksum(struct mbuf *m) 1000 { 1001 struct ip *ip; 1002 u_short csum, offset; 1003 1004 ip = mtod(m, struct ip *); 1005 offset = IP_VHL_HL(ip->ip_vhl) << 2 ; 1006 csum = in_cksum_skip(m, ip->ip_len, offset); 1007 if (m->m_pkthdr.csum_flags & CSUM_UDP && csum == 0) 1008 csum = 0xffff; 1009 offset += m->m_pkthdr.csum_data; /* checksum offset */ 1010 1011 if (offset + sizeof(u_short) > m->m_len) { 1012 printf("delayed m_pullup, m->len: %d off: %d p: %d\n", 1013 m->m_len, offset, ip->ip_p); 1014 /* 1015 * XXX 1016 * this shouldn't happen, but if it does, the 1017 * correct behavior may be to insert the checksum 1018 * in the existing chain instead of rearranging it. 1019 */ 1020 m = m_pullup(m, offset + sizeof(u_short)); 1021 } 1022 *(u_short *)(m->m_data + offset) = csum; 1023 } 1024 1025 /* 1026 * Insert IP options into preformed packet. 1027 * Adjust IP destination as required for IP source routing, 1028 * as indicated by a non-zero in_addr at the start of the options. 1029 * 1030 * XXX This routine assumes that the packet has no options in place. 1031 */ 1032 static struct mbuf * 1033 ip_insertoptions(m, opt, phlen) 1034 register struct mbuf *m; 1035 struct mbuf *opt; 1036 int *phlen; 1037 { 1038 register struct ipoption *p = mtod(opt, struct ipoption *); 1039 struct mbuf *n; 1040 register struct ip *ip = mtod(m, struct ip *); 1041 unsigned optlen; 1042 1043 optlen = opt->m_len - sizeof(p->ipopt_dst); 1044 if (optlen + (u_short)ip->ip_len > IP_MAXPACKET) 1045 return (m); /* XXX should fail */ 1046 if (p->ipopt_dst.s_addr) 1047 ip->ip_dst = p->ipopt_dst; 1048 if (m->m_flags & M_EXT || m->m_data - optlen < m->m_pktdat) { 1049 MGETHDR(n, M_DONTWAIT, MT_HEADER); 1050 if (n == 0) 1051 return (m); 1052 n->m_pkthdr.rcvif = (struct ifnet *)0; 1053 n->m_pkthdr.len = m->m_pkthdr.len + optlen; 1054 m->m_len -= sizeof(struct ip); 1055 m->m_data += sizeof(struct ip); 1056 n->m_next = m; 1057 m = n; 1058 m->m_len = optlen + sizeof(struct ip); 1059 m->m_data += max_linkhdr; 1060 (void)memcpy(mtod(m, void *), ip, sizeof(struct ip)); 1061 } else { 1062 m->m_data -= optlen; 1063 m->m_len += optlen; 1064 m->m_pkthdr.len += optlen; 1065 ovbcopy((caddr_t)ip, mtod(m, caddr_t), sizeof(struct ip)); 1066 } 1067 ip = mtod(m, struct ip *); 1068 bcopy(p->ipopt_list, ip + 1, optlen); 1069 *phlen = sizeof(struct ip) + optlen; 1070 ip->ip_vhl = IP_MAKE_VHL(IPVERSION, *phlen >> 2); 1071 ip->ip_len += optlen; 1072 return (m); 1073 } 1074 1075 /* 1076 * Copy options from ip to jp, 1077 * omitting those not copied during fragmentation. 1078 */ 1079 int 1080 ip_optcopy(ip, jp) 1081 struct ip *ip, *jp; 1082 { 1083 register u_char *cp, *dp; 1084 int opt, optlen, cnt; 1085 1086 cp = (u_char *)(ip + 1); 1087 dp = (u_char *)(jp + 1); 1088 cnt = (IP_VHL_HL(ip->ip_vhl) << 2) - sizeof (struct ip); 1089 for (; cnt > 0; cnt -= optlen, cp += optlen) { 1090 opt = cp[0]; 1091 if (opt == IPOPT_EOL) 1092 break; 1093 if (opt == IPOPT_NOP) { 1094 /* Preserve for IP mcast tunnel's LSRR alignment. */ 1095 *dp++ = IPOPT_NOP; 1096 optlen = 1; 1097 continue; 1098 } 1099 #ifdef DIAGNOSTIC 1100 if (cnt < IPOPT_OLEN + sizeof(*cp)) 1101 panic("malformed IPv4 option passed to ip_optcopy"); 1102 #endif 1103 optlen = cp[IPOPT_OLEN]; 1104 #ifdef DIAGNOSTIC 1105 if (optlen < IPOPT_OLEN + sizeof(*cp) || optlen > cnt) 1106 panic("malformed IPv4 option passed to ip_optcopy"); 1107 #endif 1108 /* bogus lengths should have been caught by ip_dooptions */ 1109 if (optlen > cnt) 1110 optlen = cnt; 1111 if (IPOPT_COPIED(opt)) { 1112 bcopy(cp, dp, optlen); 1113 dp += optlen; 1114 } 1115 } 1116 for (optlen = dp - (u_char *)(jp+1); optlen & 0x3; optlen++) 1117 *dp++ = IPOPT_EOL; 1118 return (optlen); 1119 } 1120 1121 /* 1122 * IP socket option processing. 1123 */ 1124 int 1125 ip_ctloutput(so, sopt) 1126 struct socket *so; 1127 struct sockopt *sopt; 1128 { 1129 struct inpcb *inp = sotoinpcb(so); 1130 int error, optval; 1131 1132 error = optval = 0; 1133 if (sopt->sopt_level != IPPROTO_IP) { 1134 return (EINVAL); 1135 } 1136 1137 switch (sopt->sopt_dir) { 1138 case SOPT_SET: 1139 switch (sopt->sopt_name) { 1140 case IP_OPTIONS: 1141 #ifdef notyet 1142 case IP_RETOPTS: 1143 #endif 1144 { 1145 struct mbuf *m; 1146 if (sopt->sopt_valsize > MLEN) { 1147 error = EMSGSIZE; 1148 break; 1149 } 1150 MGET(m, sopt->sopt_td ? M_TRYWAIT : M_DONTWAIT, MT_HEADER); 1151 if (m == 0) { 1152 error = ENOBUFS; 1153 break; 1154 } 1155 m->m_len = sopt->sopt_valsize; 1156 error = sooptcopyin(sopt, mtod(m, char *), m->m_len, 1157 m->m_len); 1158 1159 return (ip_pcbopts(sopt->sopt_name, &inp->inp_options, 1160 m)); 1161 } 1162 1163 case IP_TOS: 1164 case IP_TTL: 1165 case IP_RECVOPTS: 1166 case IP_RECVRETOPTS: 1167 case IP_RECVDSTADDR: 1168 case IP_RECVIF: 1169 #if defined(NFAITH) && NFAITH > 0 1170 case IP_FAITH: 1171 #endif 1172 error = sooptcopyin(sopt, &optval, sizeof optval, 1173 sizeof optval); 1174 if (error) 1175 break; 1176 1177 switch (sopt->sopt_name) { 1178 case IP_TOS: 1179 inp->inp_ip_tos = optval; 1180 break; 1181 1182 case IP_TTL: 1183 inp->inp_ip_ttl = optval; 1184 break; 1185 #define OPTSET(bit) \ 1186 if (optval) \ 1187 inp->inp_flags |= bit; \ 1188 else \ 1189 inp->inp_flags &= ~bit; 1190 1191 case IP_RECVOPTS: 1192 OPTSET(INP_RECVOPTS); 1193 break; 1194 1195 case IP_RECVRETOPTS: 1196 OPTSET(INP_RECVRETOPTS); 1197 break; 1198 1199 case IP_RECVDSTADDR: 1200 OPTSET(INP_RECVDSTADDR); 1201 break; 1202 1203 case IP_RECVIF: 1204 OPTSET(INP_RECVIF); 1205 break; 1206 1207 #if defined(NFAITH) && NFAITH > 0 1208 case IP_FAITH: 1209 OPTSET(INP_FAITH); 1210 break; 1211 #endif 1212 } 1213 break; 1214 #undef OPTSET 1215 1216 case IP_MULTICAST_IF: 1217 case IP_MULTICAST_VIF: 1218 case IP_MULTICAST_TTL: 1219 case IP_MULTICAST_LOOP: 1220 case IP_ADD_MEMBERSHIP: 1221 case IP_DROP_MEMBERSHIP: 1222 error = ip_setmoptions(sopt, &inp->inp_moptions); 1223 break; 1224 1225 case IP_PORTRANGE: 1226 error = sooptcopyin(sopt, &optval, sizeof optval, 1227 sizeof optval); 1228 if (error) 1229 break; 1230 1231 switch (optval) { 1232 case IP_PORTRANGE_DEFAULT: 1233 inp->inp_flags &= ~(INP_LOWPORT); 1234 inp->inp_flags &= ~(INP_HIGHPORT); 1235 break; 1236 1237 case IP_PORTRANGE_HIGH: 1238 inp->inp_flags &= ~(INP_LOWPORT); 1239 inp->inp_flags |= INP_HIGHPORT; 1240 break; 1241 1242 case IP_PORTRANGE_LOW: 1243 inp->inp_flags &= ~(INP_HIGHPORT); 1244 inp->inp_flags |= INP_LOWPORT; 1245 break; 1246 1247 default: 1248 error = EINVAL; 1249 break; 1250 } 1251 break; 1252 1253 #ifdef IPSEC 1254 case IP_IPSEC_POLICY: 1255 { 1256 caddr_t req; 1257 size_t len = 0; 1258 int priv; 1259 struct mbuf *m; 1260 int optname; 1261 1262 if ((error = soopt_getm(sopt, &m)) != 0) /* XXX */ 1263 break; 1264 if ((error = soopt_mcopyin(sopt, m)) != 0) /* XXX */ 1265 break; 1266 priv = (sopt->sopt_td != NULL && 1267 suser_td(sopt->sopt_td) != 0) ? 0 : 1; 1268 req = mtod(m, caddr_t); 1269 len = m->m_len; 1270 optname = sopt->sopt_name; 1271 error = ipsec4_set_policy(inp, optname, req, len, priv); 1272 m_freem(m); 1273 break; 1274 } 1275 #endif /*IPSEC*/ 1276 1277 default: 1278 error = ENOPROTOOPT; 1279 break; 1280 } 1281 break; 1282 1283 case SOPT_GET: 1284 switch (sopt->sopt_name) { 1285 case IP_OPTIONS: 1286 case IP_RETOPTS: 1287 if (inp->inp_options) 1288 error = sooptcopyout(sopt, 1289 mtod(inp->inp_options, 1290 char *), 1291 inp->inp_options->m_len); 1292 else 1293 sopt->sopt_valsize = 0; 1294 break; 1295 1296 case IP_TOS: 1297 case IP_TTL: 1298 case IP_RECVOPTS: 1299 case IP_RECVRETOPTS: 1300 case IP_RECVDSTADDR: 1301 case IP_RECVIF: 1302 case IP_PORTRANGE: 1303 #if defined(NFAITH) && NFAITH > 0 1304 case IP_FAITH: 1305 #endif 1306 switch (sopt->sopt_name) { 1307 1308 case IP_TOS: 1309 optval = inp->inp_ip_tos; 1310 break; 1311 1312 case IP_TTL: 1313 optval = inp->inp_ip_ttl; 1314 break; 1315 1316 #define OPTBIT(bit) (inp->inp_flags & bit ? 1 : 0) 1317 1318 case IP_RECVOPTS: 1319 optval = OPTBIT(INP_RECVOPTS); 1320 break; 1321 1322 case IP_RECVRETOPTS: 1323 optval = OPTBIT(INP_RECVRETOPTS); 1324 break; 1325 1326 case IP_RECVDSTADDR: 1327 optval = OPTBIT(INP_RECVDSTADDR); 1328 break; 1329 1330 case IP_RECVIF: 1331 optval = OPTBIT(INP_RECVIF); 1332 break; 1333 1334 case IP_PORTRANGE: 1335 if (inp->inp_flags & INP_HIGHPORT) 1336 optval = IP_PORTRANGE_HIGH; 1337 else if (inp->inp_flags & INP_LOWPORT) 1338 optval = IP_PORTRANGE_LOW; 1339 else 1340 optval = 0; 1341 break; 1342 1343 #if defined(NFAITH) && NFAITH > 0 1344 case IP_FAITH: 1345 optval = OPTBIT(INP_FAITH); 1346 break; 1347 #endif 1348 } 1349 error = sooptcopyout(sopt, &optval, sizeof optval); 1350 break; 1351 1352 case IP_MULTICAST_IF: 1353 case IP_MULTICAST_VIF: 1354 case IP_MULTICAST_TTL: 1355 case IP_MULTICAST_LOOP: 1356 case IP_ADD_MEMBERSHIP: 1357 case IP_DROP_MEMBERSHIP: 1358 error = ip_getmoptions(sopt, inp->inp_moptions); 1359 break; 1360 1361 #ifdef IPSEC 1362 case IP_IPSEC_POLICY: 1363 { 1364 struct mbuf *m = NULL; 1365 caddr_t req = NULL; 1366 size_t len = 0; 1367 1368 if (m != 0) { 1369 req = mtod(m, caddr_t); 1370 len = m->m_len; 1371 } 1372 error = ipsec4_get_policy(sotoinpcb(so), req, len, &m); 1373 if (error == 0) 1374 error = soopt_mcopyout(sopt, m); /* XXX */ 1375 if (error == 0) 1376 m_freem(m); 1377 break; 1378 } 1379 #endif /*IPSEC*/ 1380 1381 default: 1382 error = ENOPROTOOPT; 1383 break; 1384 } 1385 break; 1386 } 1387 return (error); 1388 } 1389 1390 /* 1391 * Set up IP options in pcb for insertion in output packets. 1392 * Store in mbuf with pointer in pcbopt, adding pseudo-option 1393 * with destination address if source routed. 1394 */ 1395 static int 1396 ip_pcbopts(optname, pcbopt, m) 1397 int optname; 1398 struct mbuf **pcbopt; 1399 register struct mbuf *m; 1400 { 1401 register int cnt, optlen; 1402 register u_char *cp; 1403 u_char opt; 1404 1405 /* turn off any old options */ 1406 if (*pcbopt) 1407 (void)m_free(*pcbopt); 1408 *pcbopt = 0; 1409 if (m == (struct mbuf *)0 || m->m_len == 0) { 1410 /* 1411 * Only turning off any previous options. 1412 */ 1413 if (m) 1414 (void)m_free(m); 1415 return (0); 1416 } 1417 1418 if (m->m_len % sizeof(int32_t)) 1419 goto bad; 1420 /* 1421 * IP first-hop destination address will be stored before 1422 * actual options; move other options back 1423 * and clear it when none present. 1424 */ 1425 if (m->m_data + m->m_len + sizeof(struct in_addr) >= &m->m_dat[MLEN]) 1426 goto bad; 1427 cnt = m->m_len; 1428 m->m_len += sizeof(struct in_addr); 1429 cp = mtod(m, u_char *) + sizeof(struct in_addr); 1430 ovbcopy(mtod(m, caddr_t), (caddr_t)cp, (unsigned)cnt); 1431 bzero(mtod(m, caddr_t), sizeof(struct in_addr)); 1432 1433 for (; cnt > 0; cnt -= optlen, cp += optlen) { 1434 opt = cp[IPOPT_OPTVAL]; 1435 if (opt == IPOPT_EOL) 1436 break; 1437 if (opt == IPOPT_NOP) 1438 optlen = 1; 1439 else { 1440 if (cnt < IPOPT_OLEN + sizeof(*cp)) 1441 goto bad; 1442 optlen = cp[IPOPT_OLEN]; 1443 if (optlen < IPOPT_OLEN + sizeof(*cp) || optlen > cnt) 1444 goto bad; 1445 } 1446 switch (opt) { 1447 1448 default: 1449 break; 1450 1451 case IPOPT_LSRR: 1452 case IPOPT_SSRR: 1453 /* 1454 * user process specifies route as: 1455 * ->A->B->C->D 1456 * D must be our final destination (but we can't 1457 * check that since we may not have connected yet). 1458 * A is first hop destination, which doesn't appear in 1459 * actual IP option, but is stored before the options. 1460 */ 1461 if (optlen < IPOPT_MINOFF - 1 + sizeof(struct in_addr)) 1462 goto bad; 1463 m->m_len -= sizeof(struct in_addr); 1464 cnt -= sizeof(struct in_addr); 1465 optlen -= sizeof(struct in_addr); 1466 cp[IPOPT_OLEN] = optlen; 1467 /* 1468 * Move first hop before start of options. 1469 */ 1470 bcopy((caddr_t)&cp[IPOPT_OFFSET+1], mtod(m, caddr_t), 1471 sizeof(struct in_addr)); 1472 /* 1473 * Then copy rest of options back 1474 * to close up the deleted entry. 1475 */ 1476 ovbcopy((caddr_t)(&cp[IPOPT_OFFSET+1] + 1477 sizeof(struct in_addr)), 1478 (caddr_t)&cp[IPOPT_OFFSET+1], 1479 (unsigned)cnt + sizeof(struct in_addr)); 1480 break; 1481 } 1482 } 1483 if (m->m_len > MAX_IPOPTLEN + sizeof(struct in_addr)) 1484 goto bad; 1485 *pcbopt = m; 1486 return (0); 1487 1488 bad: 1489 (void)m_free(m); 1490 return (EINVAL); 1491 } 1492 1493 /* 1494 * XXX 1495 * The whole multicast option thing needs to be re-thought. 1496 * Several of these options are equally applicable to non-multicast 1497 * transmission, and one (IP_MULTICAST_TTL) totally duplicates a 1498 * standard option (IP_TTL). 1499 */ 1500 1501 /* 1502 * following RFC1724 section 3.3, 0.0.0.0/8 is interpreted as interface index. 1503 */ 1504 static struct ifnet * 1505 ip_multicast_if(a, ifindexp) 1506 struct in_addr *a; 1507 int *ifindexp; 1508 { 1509 int ifindex; 1510 struct ifnet *ifp; 1511 1512 if (ifindexp) 1513 *ifindexp = 0; 1514 if (ntohl(a->s_addr) >> 24 == 0) { 1515 ifindex = ntohl(a->s_addr) & 0xffffff; 1516 if (ifindex < 0 || if_index < ifindex) 1517 return NULL; 1518 ifp = ifnet_byindex(ifindex); 1519 if (ifindexp) 1520 *ifindexp = ifindex; 1521 } else { 1522 INADDR_TO_IFP(*a, ifp); 1523 } 1524 return ifp; 1525 } 1526 1527 /* 1528 * Set the IP multicast options in response to user setsockopt(). 1529 */ 1530 static int 1531 ip_setmoptions(sopt, imop) 1532 struct sockopt *sopt; 1533 struct ip_moptions **imop; 1534 { 1535 int error = 0; 1536 int i; 1537 struct in_addr addr; 1538 struct ip_mreq mreq; 1539 struct ifnet *ifp; 1540 struct ip_moptions *imo = *imop; 1541 struct route ro; 1542 struct sockaddr_in *dst; 1543 int ifindex; 1544 int s; 1545 1546 if (imo == NULL) { 1547 /* 1548 * No multicast option buffer attached to the pcb; 1549 * allocate one and initialize to default values. 1550 */ 1551 imo = (struct ip_moptions*)malloc(sizeof(*imo), M_IPMOPTS, 1552 M_WAITOK); 1553 1554 if (imo == NULL) 1555 return (ENOBUFS); 1556 *imop = imo; 1557 imo->imo_multicast_ifp = NULL; 1558 imo->imo_multicast_addr.s_addr = INADDR_ANY; 1559 imo->imo_multicast_vif = -1; 1560 imo->imo_multicast_ttl = IP_DEFAULT_MULTICAST_TTL; 1561 imo->imo_multicast_loop = IP_DEFAULT_MULTICAST_LOOP; 1562 imo->imo_num_memberships = 0; 1563 } 1564 1565 switch (sopt->sopt_name) { 1566 /* store an index number for the vif you wanna use in the send */ 1567 case IP_MULTICAST_VIF: 1568 if (legal_vif_num == 0) { 1569 error = EOPNOTSUPP; 1570 break; 1571 } 1572 error = sooptcopyin(sopt, &i, sizeof i, sizeof i); 1573 if (error) 1574 break; 1575 if (!legal_vif_num(i) && (i != -1)) { 1576 error = EINVAL; 1577 break; 1578 } 1579 imo->imo_multicast_vif = i; 1580 break; 1581 1582 case IP_MULTICAST_IF: 1583 /* 1584 * Select the interface for outgoing multicast packets. 1585 */ 1586 error = sooptcopyin(sopt, &addr, sizeof addr, sizeof addr); 1587 if (error) 1588 break; 1589 /* 1590 * INADDR_ANY is used to remove a previous selection. 1591 * When no interface is selected, a default one is 1592 * chosen every time a multicast packet is sent. 1593 */ 1594 if (addr.s_addr == INADDR_ANY) { 1595 imo->imo_multicast_ifp = NULL; 1596 break; 1597 } 1598 /* 1599 * The selected interface is identified by its local 1600 * IP address. Find the interface and confirm that 1601 * it supports multicasting. 1602 */ 1603 s = splimp(); 1604 ifp = ip_multicast_if(&addr, &ifindex); 1605 if (ifp == NULL || (ifp->if_flags & IFF_MULTICAST) == 0) { 1606 splx(s); 1607 error = EADDRNOTAVAIL; 1608 break; 1609 } 1610 imo->imo_multicast_ifp = ifp; 1611 if (ifindex) 1612 imo->imo_multicast_addr = addr; 1613 else 1614 imo->imo_multicast_addr.s_addr = INADDR_ANY; 1615 splx(s); 1616 break; 1617 1618 case IP_MULTICAST_TTL: 1619 /* 1620 * Set the IP time-to-live for outgoing multicast packets. 1621 * The original multicast API required a char argument, 1622 * which is inconsistent with the rest of the socket API. 1623 * We allow either a char or an int. 1624 */ 1625 if (sopt->sopt_valsize == 1) { 1626 u_char ttl; 1627 error = sooptcopyin(sopt, &ttl, 1, 1); 1628 if (error) 1629 break; 1630 imo->imo_multicast_ttl = ttl; 1631 } else { 1632 u_int ttl; 1633 error = sooptcopyin(sopt, &ttl, sizeof ttl, 1634 sizeof ttl); 1635 if (error) 1636 break; 1637 if (ttl > 255) 1638 error = EINVAL; 1639 else 1640 imo->imo_multicast_ttl = ttl; 1641 } 1642 break; 1643 1644 case IP_MULTICAST_LOOP: 1645 /* 1646 * Set the loopback flag for outgoing multicast packets. 1647 * Must be zero or one. The original multicast API required a 1648 * char argument, which is inconsistent with the rest 1649 * of the socket API. We allow either a char or an int. 1650 */ 1651 if (sopt->sopt_valsize == 1) { 1652 u_char loop; 1653 error = sooptcopyin(sopt, &loop, 1, 1); 1654 if (error) 1655 break; 1656 imo->imo_multicast_loop = !!loop; 1657 } else { 1658 u_int loop; 1659 error = sooptcopyin(sopt, &loop, sizeof loop, 1660 sizeof loop); 1661 if (error) 1662 break; 1663 imo->imo_multicast_loop = !!loop; 1664 } 1665 break; 1666 1667 case IP_ADD_MEMBERSHIP: 1668 /* 1669 * Add a multicast group membership. 1670 * Group must be a valid IP multicast address. 1671 */ 1672 error = sooptcopyin(sopt, &mreq, sizeof mreq, sizeof mreq); 1673 if (error) 1674 break; 1675 1676 if (!IN_MULTICAST(ntohl(mreq.imr_multiaddr.s_addr))) { 1677 error = EINVAL; 1678 break; 1679 } 1680 s = splimp(); 1681 /* 1682 * If no interface address was provided, use the interface of 1683 * the route to the given multicast address. 1684 */ 1685 if (mreq.imr_interface.s_addr == INADDR_ANY) { 1686 bzero((caddr_t)&ro, sizeof(ro)); 1687 dst = (struct sockaddr_in *)&ro.ro_dst; 1688 dst->sin_len = sizeof(*dst); 1689 dst->sin_family = AF_INET; 1690 dst->sin_addr = mreq.imr_multiaddr; 1691 rtalloc(&ro); 1692 if (ro.ro_rt == NULL) { 1693 error = EADDRNOTAVAIL; 1694 splx(s); 1695 break; 1696 } 1697 ifp = ro.ro_rt->rt_ifp; 1698 rtfree(ro.ro_rt); 1699 } 1700 else { 1701 ifp = ip_multicast_if(&mreq.imr_interface, NULL); 1702 } 1703 1704 /* 1705 * See if we found an interface, and confirm that it 1706 * supports multicast. 1707 */ 1708 if (ifp == NULL || (ifp->if_flags & IFF_MULTICAST) == 0) { 1709 error = EADDRNOTAVAIL; 1710 splx(s); 1711 break; 1712 } 1713 /* 1714 * See if the membership already exists or if all the 1715 * membership slots are full. 1716 */ 1717 for (i = 0; i < imo->imo_num_memberships; ++i) { 1718 if (imo->imo_membership[i]->inm_ifp == ifp && 1719 imo->imo_membership[i]->inm_addr.s_addr 1720 == mreq.imr_multiaddr.s_addr) 1721 break; 1722 } 1723 if (i < imo->imo_num_memberships) { 1724 error = EADDRINUSE; 1725 splx(s); 1726 break; 1727 } 1728 if (i == IP_MAX_MEMBERSHIPS) { 1729 error = ETOOMANYREFS; 1730 splx(s); 1731 break; 1732 } 1733 /* 1734 * Everything looks good; add a new record to the multicast 1735 * address list for the given interface. 1736 */ 1737 if ((imo->imo_membership[i] = 1738 in_addmulti(&mreq.imr_multiaddr, ifp)) == NULL) { 1739 error = ENOBUFS; 1740 splx(s); 1741 break; 1742 } 1743 ++imo->imo_num_memberships; 1744 splx(s); 1745 break; 1746 1747 case IP_DROP_MEMBERSHIP: 1748 /* 1749 * Drop a multicast group membership. 1750 * Group must be a valid IP multicast address. 1751 */ 1752 error = sooptcopyin(sopt, &mreq, sizeof mreq, sizeof mreq); 1753 if (error) 1754 break; 1755 1756 if (!IN_MULTICAST(ntohl(mreq.imr_multiaddr.s_addr))) { 1757 error = EINVAL; 1758 break; 1759 } 1760 1761 s = splimp(); 1762 /* 1763 * If an interface address was specified, get a pointer 1764 * to its ifnet structure. 1765 */ 1766 if (mreq.imr_interface.s_addr == INADDR_ANY) 1767 ifp = NULL; 1768 else { 1769 ifp = ip_multicast_if(&mreq.imr_interface, NULL); 1770 if (ifp == NULL) { 1771 error = EADDRNOTAVAIL; 1772 splx(s); 1773 break; 1774 } 1775 } 1776 /* 1777 * Find the membership in the membership array. 1778 */ 1779 for (i = 0; i < imo->imo_num_memberships; ++i) { 1780 if ((ifp == NULL || 1781 imo->imo_membership[i]->inm_ifp == ifp) && 1782 imo->imo_membership[i]->inm_addr.s_addr == 1783 mreq.imr_multiaddr.s_addr) 1784 break; 1785 } 1786 if (i == imo->imo_num_memberships) { 1787 error = EADDRNOTAVAIL; 1788 splx(s); 1789 break; 1790 } 1791 /* 1792 * Give up the multicast address record to which the 1793 * membership points. 1794 */ 1795 in_delmulti(imo->imo_membership[i]); 1796 /* 1797 * Remove the gap in the membership array. 1798 */ 1799 for (++i; i < imo->imo_num_memberships; ++i) 1800 imo->imo_membership[i-1] = imo->imo_membership[i]; 1801 --imo->imo_num_memberships; 1802 splx(s); 1803 break; 1804 1805 default: 1806 error = EOPNOTSUPP; 1807 break; 1808 } 1809 1810 /* 1811 * If all options have default values, no need to keep the mbuf. 1812 */ 1813 if (imo->imo_multicast_ifp == NULL && 1814 imo->imo_multicast_vif == -1 && 1815 imo->imo_multicast_ttl == IP_DEFAULT_MULTICAST_TTL && 1816 imo->imo_multicast_loop == IP_DEFAULT_MULTICAST_LOOP && 1817 imo->imo_num_memberships == 0) { 1818 free(*imop, M_IPMOPTS); 1819 *imop = NULL; 1820 } 1821 1822 return (error); 1823 } 1824 1825 /* 1826 * Return the IP multicast options in response to user getsockopt(). 1827 */ 1828 static int 1829 ip_getmoptions(sopt, imo) 1830 struct sockopt *sopt; 1831 register struct ip_moptions *imo; 1832 { 1833 struct in_addr addr; 1834 struct in_ifaddr *ia; 1835 int error, optval; 1836 u_char coptval; 1837 1838 error = 0; 1839 switch (sopt->sopt_name) { 1840 case IP_MULTICAST_VIF: 1841 if (imo != NULL) 1842 optval = imo->imo_multicast_vif; 1843 else 1844 optval = -1; 1845 error = sooptcopyout(sopt, &optval, sizeof optval); 1846 break; 1847 1848 case IP_MULTICAST_IF: 1849 if (imo == NULL || imo->imo_multicast_ifp == NULL) 1850 addr.s_addr = INADDR_ANY; 1851 else if (imo->imo_multicast_addr.s_addr) { 1852 /* return the value user has set */ 1853 addr = imo->imo_multicast_addr; 1854 } else { 1855 IFP_TO_IA(imo->imo_multicast_ifp, ia); 1856 addr.s_addr = (ia == NULL) ? INADDR_ANY 1857 : IA_SIN(ia)->sin_addr.s_addr; 1858 } 1859 error = sooptcopyout(sopt, &addr, sizeof addr); 1860 break; 1861 1862 case IP_MULTICAST_TTL: 1863 if (imo == 0) 1864 optval = coptval = IP_DEFAULT_MULTICAST_TTL; 1865 else 1866 optval = coptval = imo->imo_multicast_ttl; 1867 if (sopt->sopt_valsize == 1) 1868 error = sooptcopyout(sopt, &coptval, 1); 1869 else 1870 error = sooptcopyout(sopt, &optval, sizeof optval); 1871 break; 1872 1873 case IP_MULTICAST_LOOP: 1874 if (imo == 0) 1875 optval = coptval = IP_DEFAULT_MULTICAST_LOOP; 1876 else 1877 optval = coptval = imo->imo_multicast_loop; 1878 if (sopt->sopt_valsize == 1) 1879 error = sooptcopyout(sopt, &coptval, 1); 1880 else 1881 error = sooptcopyout(sopt, &optval, sizeof optval); 1882 break; 1883 1884 default: 1885 error = ENOPROTOOPT; 1886 break; 1887 } 1888 return (error); 1889 } 1890 1891 /* 1892 * Discard the IP multicast options. 1893 */ 1894 void 1895 ip_freemoptions(imo) 1896 register struct ip_moptions *imo; 1897 { 1898 register int i; 1899 1900 if (imo != NULL) { 1901 for (i = 0; i < imo->imo_num_memberships; ++i) 1902 in_delmulti(imo->imo_membership[i]); 1903 free(imo, M_IPMOPTS); 1904 } 1905 } 1906 1907 /* 1908 * Routine called from ip_output() to loop back a copy of an IP multicast 1909 * packet to the input queue of a specified interface. Note that this 1910 * calls the output routine of the loopback "driver", but with an interface 1911 * pointer that might NOT be a loopback interface -- evil, but easier than 1912 * replicating that code here. 1913 */ 1914 static void 1915 ip_mloopback(ifp, m, dst, hlen) 1916 struct ifnet *ifp; 1917 register struct mbuf *m; 1918 register struct sockaddr_in *dst; 1919 int hlen; 1920 { 1921 register struct ip *ip; 1922 struct mbuf *copym; 1923 1924 copym = m_copy(m, 0, M_COPYALL); 1925 if (copym != NULL && (copym->m_flags & M_EXT || copym->m_len < hlen)) 1926 copym = m_pullup(copym, hlen); 1927 if (copym != NULL) { 1928 /* 1929 * We don't bother to fragment if the IP length is greater 1930 * than the interface's MTU. Can this possibly matter? 1931 */ 1932 ip = mtod(copym, struct ip *); 1933 HTONS(ip->ip_len); 1934 HTONS(ip->ip_off); 1935 ip->ip_sum = 0; 1936 if (ip->ip_vhl == IP_VHL_BORING) { 1937 ip->ip_sum = in_cksum_hdr(ip); 1938 } else { 1939 ip->ip_sum = in_cksum(copym, hlen); 1940 } 1941 /* 1942 * NB: 1943 * It's not clear whether there are any lingering 1944 * reentrancy problems in other areas which might 1945 * be exposed by using ip_input directly (in 1946 * particular, everything which modifies the packet 1947 * in-place). Yet another option is using the 1948 * protosw directly to deliver the looped back 1949 * packet. For the moment, we'll err on the side 1950 * of safety by using if_simloop(). 1951 */ 1952 #if 1 /* XXX */ 1953 if (dst->sin_family != AF_INET) { 1954 printf("ip_mloopback: bad address family %d\n", 1955 dst->sin_family); 1956 dst->sin_family = AF_INET; 1957 } 1958 #endif 1959 1960 #ifdef notdef 1961 copym->m_pkthdr.rcvif = ifp; 1962 ip_input(copym); 1963 #else 1964 /* if the checksum hasn't been computed, mark it as valid */ 1965 if (copym->m_pkthdr.csum_flags & CSUM_DELAY_DATA) { 1966 copym->m_pkthdr.csum_flags |= 1967 CSUM_DATA_VALID | CSUM_PSEUDO_HDR; 1968 copym->m_pkthdr.csum_data = 0xffff; 1969 } 1970 if_simloop(ifp, copym, dst->sin_family, 0); 1971 #endif 1972 } 1973 } 1974