1 /*- 2 * Copyright (c) 1982, 1989, 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 * 4. Neither the name of the University nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * @(#)if_ethersubr.c 8.1 (Berkeley) 6/10/93 30 * $FreeBSD$ 31 */ 32 33 #include "opt_atalk.h" 34 #include "opt_inet.h" 35 #include "opt_inet6.h" 36 #include "opt_ipx.h" 37 #include "opt_mac.h" 38 #include "opt_netgraph.h" 39 #include "opt_carp.h" 40 41 #include <sys/param.h> 42 #include <sys/systm.h> 43 #include <sys/kernel.h> 44 #include <sys/malloc.h> 45 #include <sys/module.h> 46 #include <sys/mbuf.h> 47 #include <sys/random.h> 48 #include <sys/socket.h> 49 #include <sys/sockio.h> 50 #include <sys/sysctl.h> 51 52 #include <net/if.h> 53 #include <net/if_arp.h> 54 #include <net/netisr.h> 55 #include <net/route.h> 56 #include <net/if_llc.h> 57 #include <net/if_dl.h> 58 #include <net/if_types.h> 59 #include <net/bpf.h> 60 #include <net/ethernet.h> 61 #include <net/if_bridgevar.h> 62 #include <net/if_vlan_var.h> 63 64 #if defined(INET) || defined(INET6) 65 #include <netinet/in.h> 66 #include <netinet/in_var.h> 67 #include <netinet/if_ether.h> 68 #include <netinet/ip_fw.h> 69 #include <netinet/ip_dummynet.h> 70 #endif 71 #ifdef INET6 72 #include <netinet6/nd6.h> 73 #endif 74 75 #ifdef DEV_CARP 76 #include <netinet/ip_carp.h> 77 #endif 78 79 #ifdef IPX 80 #include <netipx/ipx.h> 81 #include <netipx/ipx_if.h> 82 #endif 83 int (*ef_inputp)(struct ifnet*, struct ether_header *eh, struct mbuf *m); 84 int (*ef_outputp)(struct ifnet *ifp, struct mbuf **mp, 85 struct sockaddr *dst, short *tp, int *hlen); 86 87 #ifdef NETATALK 88 #include <netatalk/at.h> 89 #include <netatalk/at_var.h> 90 #include <netatalk/at_extern.h> 91 92 #define llc_snap_org_code llc_un.type_snap.org_code 93 #define llc_snap_ether_type llc_un.type_snap.ether_type 94 95 extern u_char at_org_code[3]; 96 extern u_char aarp_org_code[3]; 97 #endif /* NETATALK */ 98 99 #include <security/mac/mac_framework.h> 100 101 /* netgraph node hooks for ng_ether(4) */ 102 void (*ng_ether_input_p)(struct ifnet *ifp, struct mbuf **mp); 103 void (*ng_ether_input_orphan_p)(struct ifnet *ifp, struct mbuf *m); 104 int (*ng_ether_output_p)(struct ifnet *ifp, struct mbuf **mp); 105 void (*ng_ether_attach_p)(struct ifnet *ifp); 106 void (*ng_ether_detach_p)(struct ifnet *ifp); 107 108 void (*vlan_input_p)(struct ifnet *, struct mbuf *); 109 110 /* if_bridge(4) support */ 111 struct mbuf *(*bridge_input_p)(struct ifnet *, struct mbuf *); 112 int (*bridge_output_p)(struct ifnet *, struct mbuf *, 113 struct sockaddr *, struct rtentry *); 114 void (*bridge_dn_p)(struct mbuf *, struct ifnet *); 115 116 static const u_char etherbroadcastaddr[ETHER_ADDR_LEN] = 117 { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff }; 118 119 static int ether_resolvemulti(struct ifnet *, struct sockaddr **, 120 struct sockaddr *); 121 122 /* XXX: should be in an arp support file, not here */ 123 MALLOC_DEFINE(M_ARPCOM, "arpcom", "802.* interface internals"); 124 125 #define senderr(e) do { error = (e); goto bad;} while (0) 126 127 #if defined(INET) || defined(INET6) 128 int 129 ether_ipfw_chk(struct mbuf **m0, struct ifnet *dst, 130 struct ip_fw **rule, int shared); 131 static int ether_ipfw; 132 #endif 133 134 /* 135 * Ethernet output routine. 136 * Encapsulate a packet of type family for the local net. 137 * Use trailer local net encapsulation if enough data in first 138 * packet leaves a multiple of 512 bytes of data in remainder. 139 */ 140 int 141 ether_output(struct ifnet *ifp, struct mbuf *m, 142 struct sockaddr *dst, struct rtentry *rt0) 143 { 144 short type; 145 int error, hdrcmplt = 0; 146 u_char esrc[ETHER_ADDR_LEN], edst[ETHER_ADDR_LEN]; 147 struct ether_header *eh; 148 int loop_copy = 1; 149 int hlen; /* link layer header length */ 150 151 #ifdef MAC 152 error = mac_check_ifnet_transmit(ifp, m); 153 if (error) 154 senderr(error); 155 #endif 156 157 if (ifp->if_flags & IFF_MONITOR) 158 senderr(ENETDOWN); 159 if (!((ifp->if_flags & IFF_UP) && 160 (ifp->if_drv_flags & IFF_DRV_RUNNING))) 161 senderr(ENETDOWN); 162 163 hlen = ETHER_HDR_LEN; 164 switch (dst->sa_family) { 165 #ifdef INET 166 case AF_INET: 167 error = arpresolve(ifp, rt0, m, dst, edst); 168 if (error) 169 return (error == EWOULDBLOCK ? 0 : error); 170 type = htons(ETHERTYPE_IP); 171 break; 172 case AF_ARP: 173 { 174 struct arphdr *ah; 175 ah = mtod(m, struct arphdr *); 176 ah->ar_hrd = htons(ARPHRD_ETHER); 177 178 loop_copy = 0; /* if this is for us, don't do it */ 179 180 switch(ntohs(ah->ar_op)) { 181 case ARPOP_REVREQUEST: 182 case ARPOP_REVREPLY: 183 type = htons(ETHERTYPE_REVARP); 184 break; 185 case ARPOP_REQUEST: 186 case ARPOP_REPLY: 187 default: 188 type = htons(ETHERTYPE_ARP); 189 break; 190 } 191 192 if (m->m_flags & M_BCAST) 193 bcopy(ifp->if_broadcastaddr, edst, ETHER_ADDR_LEN); 194 else 195 bcopy(ar_tha(ah), edst, ETHER_ADDR_LEN); 196 197 } 198 break; 199 #endif 200 #ifdef INET6 201 case AF_INET6: 202 error = nd6_storelladdr(ifp, rt0, m, dst, (u_char *)edst); 203 if (error) 204 return error; 205 type = htons(ETHERTYPE_IPV6); 206 break; 207 #endif 208 #ifdef IPX 209 case AF_IPX: 210 if (ef_outputp) { 211 error = ef_outputp(ifp, &m, dst, &type, &hlen); 212 if (error) 213 goto bad; 214 } else 215 type = htons(ETHERTYPE_IPX); 216 bcopy((caddr_t)&(((struct sockaddr_ipx *)dst)->sipx_addr.x_host), 217 (caddr_t)edst, sizeof (edst)); 218 break; 219 #endif 220 #ifdef NETATALK 221 case AF_APPLETALK: 222 { 223 struct at_ifaddr *aa; 224 225 if ((aa = at_ifawithnet((struct sockaddr_at *)dst)) == NULL) 226 senderr(EHOSTUNREACH); /* XXX */ 227 if (!aarpresolve(ifp, m, (struct sockaddr_at *)dst, edst)) 228 return (0); 229 /* 230 * In the phase 2 case, need to prepend an mbuf for the llc header. 231 */ 232 if ( aa->aa_flags & AFA_PHASE2 ) { 233 struct llc llc; 234 235 M_PREPEND(m, LLC_SNAPFRAMELEN, M_DONTWAIT); 236 if (m == NULL) 237 senderr(ENOBUFS); 238 llc.llc_dsap = llc.llc_ssap = LLC_SNAP_LSAP; 239 llc.llc_control = LLC_UI; 240 bcopy(at_org_code, llc.llc_snap_org_code, sizeof(at_org_code)); 241 llc.llc_snap_ether_type = htons( ETHERTYPE_AT ); 242 bcopy(&llc, mtod(m, caddr_t), LLC_SNAPFRAMELEN); 243 type = htons(m->m_pkthdr.len); 244 hlen = LLC_SNAPFRAMELEN + ETHER_HDR_LEN; 245 } else { 246 type = htons(ETHERTYPE_AT); 247 } 248 break; 249 } 250 #endif /* NETATALK */ 251 252 case pseudo_AF_HDRCMPLT: 253 hdrcmplt = 1; 254 eh = (struct ether_header *)dst->sa_data; 255 (void)memcpy(esrc, eh->ether_shost, sizeof (esrc)); 256 /* FALLTHROUGH */ 257 258 case AF_UNSPEC: 259 loop_copy = 0; /* if this is for us, don't do it */ 260 eh = (struct ether_header *)dst->sa_data; 261 (void)memcpy(edst, eh->ether_dhost, sizeof (edst)); 262 type = eh->ether_type; 263 break; 264 265 default: 266 if_printf(ifp, "can't handle af%d\n", dst->sa_family); 267 senderr(EAFNOSUPPORT); 268 } 269 270 /* 271 * Add local net header. If no space in first mbuf, 272 * allocate another. 273 */ 274 M_PREPEND(m, ETHER_HDR_LEN, M_DONTWAIT); 275 if (m == NULL) 276 senderr(ENOBUFS); 277 eh = mtod(m, struct ether_header *); 278 (void)memcpy(&eh->ether_type, &type, 279 sizeof(eh->ether_type)); 280 (void)memcpy(eh->ether_dhost, edst, sizeof (edst)); 281 if (hdrcmplt) 282 (void)memcpy(eh->ether_shost, esrc, 283 sizeof(eh->ether_shost)); 284 else 285 (void)memcpy(eh->ether_shost, IF_LLADDR(ifp), 286 sizeof(eh->ether_shost)); 287 288 /* 289 * If a simplex interface, and the packet is being sent to our 290 * Ethernet address or a broadcast address, loopback a copy. 291 * XXX To make a simplex device behave exactly like a duplex 292 * device, we should copy in the case of sending to our own 293 * ethernet address (thus letting the original actually appear 294 * on the wire). However, we don't do that here for security 295 * reasons and compatibility with the original behavior. 296 */ 297 if ((ifp->if_flags & IFF_SIMPLEX) && loop_copy && 298 m_tag_find(m, PACKET_TAG_PF_ROUTED, NULL) == NULL) { 299 int csum_flags = 0; 300 301 if (m->m_pkthdr.csum_flags & CSUM_IP) 302 csum_flags |= (CSUM_IP_CHECKED|CSUM_IP_VALID); 303 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) 304 csum_flags |= (CSUM_DATA_VALID|CSUM_PSEUDO_HDR); 305 306 if (m->m_flags & M_BCAST) { 307 struct mbuf *n; 308 309 if ((n = m_copy(m, 0, (int)M_COPYALL)) != NULL) { 310 n->m_pkthdr.csum_flags |= csum_flags; 311 if (csum_flags & CSUM_DATA_VALID) 312 n->m_pkthdr.csum_data = 0xffff; 313 (void)if_simloop(ifp, n, dst->sa_family, hlen); 314 } else 315 ifp->if_iqdrops++; 316 } else if (bcmp(eh->ether_dhost, eh->ether_shost, 317 ETHER_ADDR_LEN) == 0) { 318 m->m_pkthdr.csum_flags |= csum_flags; 319 if (csum_flags & CSUM_DATA_VALID) 320 m->m_pkthdr.csum_data = 0xffff; 321 (void) if_simloop(ifp, m, dst->sa_family, hlen); 322 return (0); /* XXX */ 323 } 324 } 325 326 /* 327 * Bridges require special output handling. 328 */ 329 if (ifp->if_bridge) { 330 BRIDGE_OUTPUT(ifp, m, error); 331 return (error); 332 } 333 334 #ifdef DEV_CARP 335 if (ifp->if_carp && 336 (error = carp_output(ifp, m, dst, NULL))) 337 goto bad; 338 #endif 339 340 /* Handle ng_ether(4) processing, if any */ 341 if (IFP2AC(ifp)->ac_netgraph != NULL) { 342 KASSERT(ng_ether_output_p != NULL, 343 ("ng_ether_output_p is NULL")); 344 if ((error = (*ng_ether_output_p)(ifp, &m)) != 0) { 345 bad: if (m != NULL) 346 m_freem(m); 347 return (error); 348 } 349 if (m == NULL) 350 return (0); 351 } 352 353 /* Continue with link-layer output */ 354 return ether_output_frame(ifp, m); 355 } 356 357 /* 358 * Ethernet link layer output routine to send a raw frame to the device. 359 * 360 * This assumes that the 14 byte Ethernet header is present and contiguous 361 * in the first mbuf (if BRIDGE'ing). 362 */ 363 int 364 ether_output_frame(struct ifnet *ifp, struct mbuf *m) 365 { 366 int error; 367 #if defined(INET) || defined(INET6) 368 struct ip_fw *rule = ip_dn_claim_rule(m); 369 370 if (IPFW_LOADED && ether_ipfw != 0) { 371 if (ether_ipfw_chk(&m, ifp, &rule, 0) == 0) { 372 if (m) { 373 m_freem(m); 374 return EACCES; /* pkt dropped */ 375 } else 376 return 0; /* consumed e.g. in a pipe */ 377 } 378 } 379 #endif 380 381 /* 382 * Queue message on interface, update output statistics if 383 * successful, and start output if interface not yet active. 384 */ 385 IFQ_HANDOFF(ifp, m, error); 386 return (error); 387 } 388 389 #if defined(INET) || defined(INET6) 390 /* 391 * ipfw processing for ethernet packets (in and out). 392 * The second parameter is NULL from ether_demux, and ifp from 393 * ether_output_frame. 394 */ 395 int 396 ether_ipfw_chk(struct mbuf **m0, struct ifnet *dst, 397 struct ip_fw **rule, int shared) 398 { 399 struct ether_header *eh; 400 struct ether_header save_eh; 401 struct mbuf *m; 402 int i; 403 struct ip_fw_args args; 404 405 if (*rule != NULL && fw_one_pass) 406 return 1; /* dummynet packet, already partially processed */ 407 408 /* 409 * I need some amt of data to be contiguous, and in case others need 410 * the packet (shared==1) also better be in the first mbuf. 411 */ 412 m = *m0; 413 i = min( m->m_pkthdr.len, max_protohdr); 414 if ( shared || m->m_len < i) { 415 m = m_pullup(m, i); 416 if (m == NULL) { 417 *m0 = m; 418 return 0; 419 } 420 } 421 eh = mtod(m, struct ether_header *); 422 save_eh = *eh; /* save copy for restore below */ 423 m_adj(m, ETHER_HDR_LEN); /* strip ethernet header */ 424 425 args.m = m; /* the packet we are looking at */ 426 args.oif = dst; /* destination, if any */ 427 args.rule = *rule; /* matching rule to restart */ 428 args.next_hop = NULL; /* we do not support forward yet */ 429 args.eh = &save_eh; /* MAC header for bridged/MAC packets */ 430 args.inp = NULL; /* used by ipfw uid/gid/jail rules */ 431 i = ip_fw_chk_ptr(&args); 432 m = args.m; 433 if (m != NULL) { 434 /* 435 * Restore Ethernet header, as needed, in case the 436 * mbuf chain was replaced by ipfw. 437 */ 438 M_PREPEND(m, ETHER_HDR_LEN, M_DONTWAIT); 439 if (m == NULL) { 440 *m0 = m; 441 return 0; 442 } 443 if (eh != mtod(m, struct ether_header *)) 444 bcopy(&save_eh, mtod(m, struct ether_header *), 445 ETHER_HDR_LEN); 446 } 447 *m0 = m; 448 *rule = args.rule; 449 450 if (i == IP_FW_DENY) /* drop */ 451 return 0; 452 453 KASSERT(m != NULL, ("ether_ipfw_chk: m is NULL")); 454 455 if (i == IP_FW_PASS) /* a PASS rule. */ 456 return 1; 457 458 if (DUMMYNET_LOADED && (i == IP_FW_DUMMYNET)) { 459 /* 460 * Pass the pkt to dummynet, which consumes it. 461 * If shared, make a copy and keep the original. 462 */ 463 if (shared) { 464 m = m_copypacket(m, M_DONTWAIT); 465 if (m == NULL) 466 return 0; 467 } else { 468 /* 469 * Pass the original to dummynet and 470 * nothing back to the caller 471 */ 472 *m0 = NULL ; 473 } 474 ip_dn_io_ptr(m, dst ? DN_TO_ETH_OUT: DN_TO_ETH_DEMUX, &args); 475 return 0; 476 } 477 /* 478 * XXX at some point add support for divert/forward actions. 479 * If none of the above matches, we have to drop the pkt. 480 */ 481 return 0; 482 } 483 #endif 484 485 /* 486 * Process a received Ethernet packet; the packet is in the 487 * mbuf chain m with the ethernet header at the front. 488 */ 489 static void 490 ether_input(struct ifnet *ifp, struct mbuf *m) 491 { 492 struct ether_header *eh; 493 u_short etype; 494 495 /* 496 * Do consistency checks to verify assumptions 497 * made by code past this point. 498 */ 499 if ((m->m_flags & M_PKTHDR) == 0) { 500 if_printf(ifp, "discard frame w/o packet header\n"); 501 ifp->if_ierrors++; 502 m_freem(m); 503 return; 504 } 505 if (m->m_len < ETHER_HDR_LEN) { 506 /* XXX maybe should pullup? */ 507 if_printf(ifp, "discard frame w/o leading ethernet " 508 "header (len %u pkt len %u)\n", 509 m->m_len, m->m_pkthdr.len); 510 ifp->if_ierrors++; 511 m_freem(m); 512 return; 513 } 514 eh = mtod(m, struct ether_header *); 515 etype = ntohs(eh->ether_type); 516 if (m->m_pkthdr.len > 517 ETHER_MAX_FRAME(ifp, etype, m->m_flags & M_HASFCS)) { 518 if_printf(ifp, "discard oversize frame " 519 "(ether type %x flags %x len %u > max %lu)\n", 520 etype, m->m_flags, m->m_pkthdr.len, 521 ETHER_MAX_FRAME(ifp, etype, 522 m->m_flags & M_HASFCS)); 523 ifp->if_ierrors++; 524 m_freem(m); 525 return; 526 } 527 if (m->m_pkthdr.rcvif == NULL) { 528 if_printf(ifp, "discard frame w/o interface pointer\n"); 529 ifp->if_ierrors++; 530 m_freem(m); 531 return; 532 } 533 #ifdef DIAGNOSTIC 534 if (m->m_pkthdr.rcvif != ifp) { 535 if_printf(ifp, "Warning, frame marked as received on %s\n", 536 m->m_pkthdr.rcvif->if_xname); 537 } 538 #endif 539 540 #ifdef MAC 541 /* 542 * Tag the mbuf with an appropriate MAC label before any other 543 * consumers can get to it. 544 */ 545 mac_create_mbuf_from_ifnet(ifp, m); 546 #endif 547 548 /* 549 * Give bpf a chance at the packet. 550 */ 551 BPF_MTAP(ifp, m); 552 553 /* If the CRC is still on the packet, trim it off. */ 554 if (m->m_flags & M_HASFCS) { 555 m_adj(m, -ETHER_CRC_LEN); 556 m->m_flags &= ~M_HASFCS; 557 } 558 559 ifp->if_ibytes += m->m_pkthdr.len; 560 561 if (ifp->if_flags & IFF_MONITOR) { 562 /* 563 * Interface marked for monitoring; discard packet. 564 */ 565 m_freem(m); 566 return; 567 } 568 569 /* Handle ng_ether(4) processing, if any */ 570 if (IFP2AC(ifp)->ac_netgraph != NULL) { 571 KASSERT(ng_ether_input_p != NULL, 572 ("ng_ether_input_p is NULL")); 573 (*ng_ether_input_p)(ifp, &m); 574 if (m == NULL) 575 return; 576 } 577 578 /* 579 * Tap the packet off here for a bridge. bridge_input() 580 * will return NULL if it has consumed the packet, otherwise 581 * it gets processed as normal. Note that bridge_input() 582 * will always return the original packet if we need to 583 * process it locally. 584 * 585 * XXX: When changing the below block, please also look 586 * at the src/sys/netgraph/ng_ether.c:ng_ether_rcv_upper() 587 */ 588 if (ifp->if_bridge) { 589 BRIDGE_INPUT(ifp, m); 590 if (m == NULL) 591 return; 592 } 593 594 /* First chunk of an mbuf contains good entropy */ 595 if (harvest.ethernet) 596 random_harvest(m, 16, 3, 0, RANDOM_NET); 597 ether_demux(ifp, m); 598 } 599 600 /* 601 * Upper layer processing for a received Ethernet packet. 602 */ 603 void 604 ether_demux(struct ifnet *ifp, struct mbuf *m) 605 { 606 struct ether_header *eh; 607 int isr; 608 u_short ether_type; 609 #if defined(NETATALK) 610 struct llc *l; 611 #endif 612 #if defined(INET) || defined(INET6) 613 struct ip_fw *rule = ip_dn_claim_rule(m); 614 #endif 615 616 KASSERT(ifp != NULL, ("ether_demux: NULL interface pointer")); 617 618 eh = mtod(m, struct ether_header *); 619 ether_type = ntohs(eh->ether_type); 620 621 #if defined(INET) || defined(INET6) 622 if (rule) /* packet was already bridged */ 623 goto post_stats; 624 #endif 625 626 if (!(ifp->if_bridge) && 627 !((ether_type == ETHERTYPE_VLAN || m->m_flags & M_VLANTAG) && 628 ifp->if_vlantrunk != NULL)) { 629 #ifdef DEV_CARP 630 /* 631 * XXX: Okay, we need to call carp_forus() and - if it is for 632 * us jump over code that does the normal check 633 * "IF_LLADDR(ifp) == ether_dhost". The check sequence is a bit 634 * different from OpenBSD, so we jump over as few code as 635 * possible, to catch _all_ sanity checks. This needs 636 * evaluation, to see if the carp ether_dhost values break any 637 * of these checks! 638 */ 639 if (ifp->if_carp && carp_forus(ifp->if_carp, eh->ether_dhost)) 640 goto pre_stats; 641 #endif 642 /* 643 * Discard packet if upper layers shouldn't see it because it 644 * was unicast to a different Ethernet address. If the driver 645 * is working properly, then this situation can only happen 646 * when the interface is in promiscuous mode. 647 * 648 * If VLANs are active, and this packet has a VLAN tag, do 649 * not drop it here but pass it on to the VLAN layer, to 650 * give them a chance to consider it as well (e. g. in case 651 * bridging is only active on a VLAN). They will drop it if 652 * it's undesired. 653 */ 654 if ((ifp->if_flags & IFF_PROMISC) != 0 655 && !ETHER_IS_MULTICAST(eh->ether_dhost) 656 && bcmp(eh->ether_dhost, 657 IF_LLADDR(ifp), ETHER_ADDR_LEN) != 0 658 && (ifp->if_flags & IFF_PPROMISC) == 0) { 659 m_freem(m); 660 return; 661 } 662 } 663 664 #ifdef DEV_CARP 665 pre_stats: 666 #endif 667 /* Discard packet if interface is not up */ 668 if ((ifp->if_flags & IFF_UP) == 0) { 669 m_freem(m); 670 return; 671 } 672 if (ETHER_IS_MULTICAST(eh->ether_dhost)) { 673 if (bcmp(etherbroadcastaddr, eh->ether_dhost, 674 sizeof(etherbroadcastaddr)) == 0) 675 m->m_flags |= M_BCAST; 676 else 677 m->m_flags |= M_MCAST; 678 } 679 if (m->m_flags & (M_BCAST|M_MCAST)) 680 ifp->if_imcasts++; 681 682 #if defined(INET) || defined(INET6) 683 post_stats: 684 if (IPFW_LOADED && ether_ipfw != 0) { 685 if (ether_ipfw_chk(&m, NULL, &rule, 0) == 0) { 686 if (m) 687 m_freem(m); 688 return; 689 } 690 } 691 #endif 692 693 /* 694 * Check to see if the device performed the VLAN decapsulation and 695 * provided us with the tag. 696 */ 697 if (m->m_flags & M_VLANTAG) { 698 /* 699 * If no VLANs are configured, drop. 700 */ 701 if (ifp->if_vlantrunk == NULL) { 702 ifp->if_noproto++; 703 m_freem(m); 704 return; 705 } 706 /* 707 * vlan_input() will either recursively call ether_input() 708 * or drop the packet. 709 */ 710 KASSERT(vlan_input_p != NULL,("ether_input: VLAN not loaded!")); 711 (*vlan_input_p)(ifp, m); 712 return; 713 } 714 715 /* 716 * Handle protocols that expect to have the Ethernet header 717 * (and possibly FCS) intact. 718 */ 719 switch (ether_type) { 720 case ETHERTYPE_VLAN: 721 if (ifp->if_vlantrunk != NULL) { 722 KASSERT(vlan_input_p,("ether_input: VLAN not loaded!")); 723 (*vlan_input_p)(ifp, m); 724 } else { 725 ifp->if_noproto++; 726 m_freem(m); 727 } 728 return; 729 } 730 731 /* Strip off Ethernet header. */ 732 m_adj(m, ETHER_HDR_LEN); 733 734 /* If the CRC is still on the packet, trim it off. */ 735 if (m->m_flags & M_HASFCS) { 736 m_adj(m, -ETHER_CRC_LEN); 737 m->m_flags &= ~M_HASFCS; 738 } 739 740 /* Reset layer specific mbuf flags to avoid confusing upper layers. */ 741 m->m_flags &= ~(M_PROTOFLAGS); 742 743 switch (ether_type) { 744 #ifdef INET 745 case ETHERTYPE_IP: 746 if ((m = ip_fastforward(m)) == NULL) 747 return; 748 isr = NETISR_IP; 749 break; 750 751 case ETHERTYPE_ARP: 752 if (ifp->if_flags & IFF_NOARP) { 753 /* Discard packet if ARP is disabled on interface */ 754 m_freem(m); 755 return; 756 } 757 isr = NETISR_ARP; 758 break; 759 #endif 760 #ifdef IPX 761 case ETHERTYPE_IPX: 762 if (ef_inputp && ef_inputp(ifp, eh, m) == 0) 763 return; 764 isr = NETISR_IPX; 765 break; 766 #endif 767 #ifdef INET6 768 case ETHERTYPE_IPV6: 769 isr = NETISR_IPV6; 770 break; 771 #endif 772 #ifdef NETATALK 773 case ETHERTYPE_AT: 774 isr = NETISR_ATALK1; 775 break; 776 case ETHERTYPE_AARP: 777 isr = NETISR_AARP; 778 break; 779 #endif /* NETATALK */ 780 default: 781 #ifdef IPX 782 if (ef_inputp && ef_inputp(ifp, eh, m) == 0) 783 return; 784 #endif /* IPX */ 785 #if defined(NETATALK) 786 if (ether_type > ETHERMTU) 787 goto discard; 788 l = mtod(m, struct llc *); 789 if (l->llc_dsap == LLC_SNAP_LSAP && 790 l->llc_ssap == LLC_SNAP_LSAP && 791 l->llc_control == LLC_UI) { 792 if (bcmp(&(l->llc_snap_org_code)[0], at_org_code, 793 sizeof(at_org_code)) == 0 && 794 ntohs(l->llc_snap_ether_type) == ETHERTYPE_AT) { 795 m_adj(m, LLC_SNAPFRAMELEN); 796 isr = NETISR_ATALK2; 797 break; 798 } 799 if (bcmp(&(l->llc_snap_org_code)[0], aarp_org_code, 800 sizeof(aarp_org_code)) == 0 && 801 ntohs(l->llc_snap_ether_type) == ETHERTYPE_AARP) { 802 m_adj(m, LLC_SNAPFRAMELEN); 803 isr = NETISR_AARP; 804 break; 805 } 806 } 807 #endif /* NETATALK */ 808 goto discard; 809 } 810 netisr_dispatch(isr, m); 811 return; 812 813 discard: 814 /* 815 * Packet is to be discarded. If netgraph is present, 816 * hand the packet to it for last chance processing; 817 * otherwise dispose of it. 818 */ 819 if (IFP2AC(ifp)->ac_netgraph != NULL) { 820 KASSERT(ng_ether_input_orphan_p != NULL, 821 ("ng_ether_input_orphan_p is NULL")); 822 /* 823 * Put back the ethernet header so netgraph has a 824 * consistent view of inbound packets. 825 */ 826 M_PREPEND(m, ETHER_HDR_LEN, M_DONTWAIT); 827 (*ng_ether_input_orphan_p)(ifp, m); 828 return; 829 } 830 m_freem(m); 831 } 832 833 /* 834 * Convert Ethernet address to printable (loggable) representation. 835 * This routine is for compatibility; it's better to just use 836 * 837 * printf("%6D", <pointer to address>, ":"); 838 * 839 * since there's no static buffer involved. 840 */ 841 char * 842 ether_sprintf(const u_char *ap) 843 { 844 static char etherbuf[18]; 845 snprintf(etherbuf, sizeof (etherbuf), "%6D", ap, ":"); 846 return (etherbuf); 847 } 848 849 /* 850 * Perform common duties while attaching to interface list 851 */ 852 void 853 ether_ifattach(struct ifnet *ifp, const u_int8_t *lla) 854 { 855 int i; 856 struct ifaddr *ifa; 857 struct sockaddr_dl *sdl; 858 859 ifp->if_addrlen = ETHER_ADDR_LEN; 860 ifp->if_hdrlen = ETHER_HDR_LEN; 861 if_attach(ifp); 862 ifp->if_mtu = ETHERMTU; 863 ifp->if_output = ether_output; 864 ifp->if_input = ether_input; 865 ifp->if_resolvemulti = ether_resolvemulti; 866 if (ifp->if_baudrate == 0) 867 ifp->if_baudrate = IF_Mbps(10); /* just a default */ 868 ifp->if_broadcastaddr = etherbroadcastaddr; 869 870 ifa = ifp->if_addr; 871 KASSERT(ifa != NULL, ("%s: no lladdr!\n", __func__)); 872 sdl = (struct sockaddr_dl *)ifa->ifa_addr; 873 sdl->sdl_type = IFT_ETHER; 874 sdl->sdl_alen = ifp->if_addrlen; 875 bcopy(lla, LLADDR(sdl), ifp->if_addrlen); 876 877 bpfattach(ifp, DLT_EN10MB, ETHER_HDR_LEN); 878 if (ng_ether_attach_p != NULL) 879 (*ng_ether_attach_p)(ifp); 880 881 /* Announce Ethernet MAC address if non-zero. */ 882 for (i = 0; i < ifp->if_addrlen; i++) 883 if (lla[i] != 0) 884 break; 885 if (i != ifp->if_addrlen) 886 if_printf(ifp, "Ethernet address: %6D\n", lla, ":"); 887 if (debug_mpsafenet && (ifp->if_flags & IFF_NEEDSGIANT) != 0) 888 if_printf(ifp, "if_start running deferred for Giant\n"); 889 } 890 891 /* 892 * Perform common duties while detaching an Ethernet interface 893 */ 894 void 895 ether_ifdetach(struct ifnet *ifp) 896 { 897 if (IFP2AC(ifp)->ac_netgraph != NULL) { 898 KASSERT(ng_ether_detach_p != NULL, 899 ("ng_ether_detach_p is NULL")); 900 (*ng_ether_detach_p)(ifp); 901 } 902 903 bpfdetach(ifp); 904 if_detach(ifp); 905 } 906 907 SYSCTL_DECL(_net_link); 908 SYSCTL_NODE(_net_link, IFT_ETHER, ether, CTLFLAG_RW, 0, "Ethernet"); 909 #if defined(INET) || defined(INET6) 910 SYSCTL_INT(_net_link_ether, OID_AUTO, ipfw, CTLFLAG_RW, 911 ðer_ipfw,0,"Pass ether pkts through firewall"); 912 #endif 913 914 #if 0 915 /* 916 * This is for reference. We have a table-driven version 917 * of the little-endian crc32 generator, which is faster 918 * than the double-loop. 919 */ 920 uint32_t 921 ether_crc32_le(const uint8_t *buf, size_t len) 922 { 923 size_t i; 924 uint32_t crc; 925 int bit; 926 uint8_t data; 927 928 crc = 0xffffffff; /* initial value */ 929 930 for (i = 0; i < len; i++) { 931 for (data = *buf++, bit = 0; bit < 8; bit++, data >>= 1) 932 carry = (crc ^ data) & 1; 933 crc >>= 1; 934 if (carry) 935 crc = (crc ^ ETHER_CRC_POLY_LE); 936 } 937 938 return (crc); 939 } 940 #else 941 uint32_t 942 ether_crc32_le(const uint8_t *buf, size_t len) 943 { 944 static const uint32_t crctab[] = { 945 0x00000000, 0x1db71064, 0x3b6e20c8, 0x26d930ac, 946 0x76dc4190, 0x6b6b51f4, 0x4db26158, 0x5005713c, 947 0xedb88320, 0xf00f9344, 0xd6d6a3e8, 0xcb61b38c, 948 0x9b64c2b0, 0x86d3d2d4, 0xa00ae278, 0xbdbdf21c 949 }; 950 size_t i; 951 uint32_t crc; 952 953 crc = 0xffffffff; /* initial value */ 954 955 for (i = 0; i < len; i++) { 956 crc ^= buf[i]; 957 crc = (crc >> 4) ^ crctab[crc & 0xf]; 958 crc = (crc >> 4) ^ crctab[crc & 0xf]; 959 } 960 961 return (crc); 962 } 963 #endif 964 965 uint32_t 966 ether_crc32_be(const uint8_t *buf, size_t len) 967 { 968 size_t i; 969 uint32_t crc, carry; 970 int bit; 971 uint8_t data; 972 973 crc = 0xffffffff; /* initial value */ 974 975 for (i = 0; i < len; i++) { 976 for (data = *buf++, bit = 0; bit < 8; bit++, data >>= 1) { 977 carry = ((crc & 0x80000000) ? 1 : 0) ^ (data & 0x01); 978 crc <<= 1; 979 if (carry) 980 crc = (crc ^ ETHER_CRC_POLY_BE) | carry; 981 } 982 } 983 984 return (crc); 985 } 986 987 int 988 ether_ioctl(struct ifnet *ifp, int command, caddr_t data) 989 { 990 struct ifaddr *ifa = (struct ifaddr *) data; 991 struct ifreq *ifr = (struct ifreq *) data; 992 int error = 0; 993 994 switch (command) { 995 case SIOCSIFADDR: 996 ifp->if_flags |= IFF_UP; 997 998 switch (ifa->ifa_addr->sa_family) { 999 #ifdef INET 1000 case AF_INET: 1001 ifp->if_init(ifp->if_softc); /* before arpwhohas */ 1002 arp_ifinit(ifp, ifa); 1003 break; 1004 #endif 1005 #ifdef IPX 1006 /* 1007 * XXX - This code is probably wrong 1008 */ 1009 case AF_IPX: 1010 { 1011 struct ipx_addr *ina = &(IA_SIPX(ifa)->sipx_addr); 1012 1013 if (ipx_nullhost(*ina)) 1014 ina->x_host = 1015 *(union ipx_host *) 1016 IF_LLADDR(ifp); 1017 else { 1018 bcopy((caddr_t) ina->x_host.c_host, 1019 (caddr_t) IF_LLADDR(ifp), 1020 ETHER_ADDR_LEN); 1021 } 1022 1023 /* 1024 * Set new address 1025 */ 1026 ifp->if_init(ifp->if_softc); 1027 break; 1028 } 1029 #endif 1030 default: 1031 ifp->if_init(ifp->if_softc); 1032 break; 1033 } 1034 break; 1035 1036 case SIOCGIFADDR: 1037 { 1038 struct sockaddr *sa; 1039 1040 sa = (struct sockaddr *) & ifr->ifr_data; 1041 bcopy(IF_LLADDR(ifp), 1042 (caddr_t) sa->sa_data, ETHER_ADDR_LEN); 1043 } 1044 break; 1045 1046 case SIOCSIFMTU: 1047 /* 1048 * Set the interface MTU. 1049 */ 1050 if (ifr->ifr_mtu > ETHERMTU) { 1051 error = EINVAL; 1052 } else { 1053 ifp->if_mtu = ifr->ifr_mtu; 1054 } 1055 break; 1056 default: 1057 error = EINVAL; /* XXX netbsd has ENOTTY??? */ 1058 break; 1059 } 1060 return (error); 1061 } 1062 1063 static int 1064 ether_resolvemulti(struct ifnet *ifp, struct sockaddr **llsa, 1065 struct sockaddr *sa) 1066 { 1067 struct sockaddr_dl *sdl; 1068 #ifdef INET 1069 struct sockaddr_in *sin; 1070 #endif 1071 #ifdef INET6 1072 struct sockaddr_in6 *sin6; 1073 #endif 1074 u_char *e_addr; 1075 1076 switch(sa->sa_family) { 1077 case AF_LINK: 1078 /* 1079 * No mapping needed. Just check that it's a valid MC address. 1080 */ 1081 sdl = (struct sockaddr_dl *)sa; 1082 e_addr = LLADDR(sdl); 1083 if (!ETHER_IS_MULTICAST(e_addr)) 1084 return EADDRNOTAVAIL; 1085 *llsa = 0; 1086 return 0; 1087 1088 #ifdef INET 1089 case AF_INET: 1090 sin = (struct sockaddr_in *)sa; 1091 if (!IN_MULTICAST(ntohl(sin->sin_addr.s_addr))) 1092 return EADDRNOTAVAIL; 1093 MALLOC(sdl, struct sockaddr_dl *, sizeof *sdl, M_IFMADDR, 1094 M_NOWAIT|M_ZERO); 1095 if (sdl == NULL) 1096 return ENOMEM; 1097 sdl->sdl_len = sizeof *sdl; 1098 sdl->sdl_family = AF_LINK; 1099 sdl->sdl_index = ifp->if_index; 1100 sdl->sdl_type = IFT_ETHER; 1101 sdl->sdl_alen = ETHER_ADDR_LEN; 1102 e_addr = LLADDR(sdl); 1103 ETHER_MAP_IP_MULTICAST(&sin->sin_addr, e_addr); 1104 *llsa = (struct sockaddr *)sdl; 1105 return 0; 1106 #endif 1107 #ifdef INET6 1108 case AF_INET6: 1109 sin6 = (struct sockaddr_in6 *)sa; 1110 if (IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr)) { 1111 /* 1112 * An IP6 address of 0 means listen to all 1113 * of the Ethernet multicast address used for IP6. 1114 * (This is used for multicast routers.) 1115 */ 1116 ifp->if_flags |= IFF_ALLMULTI; 1117 *llsa = 0; 1118 return 0; 1119 } 1120 if (!IN6_IS_ADDR_MULTICAST(&sin6->sin6_addr)) 1121 return EADDRNOTAVAIL; 1122 MALLOC(sdl, struct sockaddr_dl *, sizeof *sdl, M_IFMADDR, 1123 M_NOWAIT|M_ZERO); 1124 if (sdl == NULL) 1125 return (ENOMEM); 1126 sdl->sdl_len = sizeof *sdl; 1127 sdl->sdl_family = AF_LINK; 1128 sdl->sdl_index = ifp->if_index; 1129 sdl->sdl_type = IFT_ETHER; 1130 sdl->sdl_alen = ETHER_ADDR_LEN; 1131 e_addr = LLADDR(sdl); 1132 ETHER_MAP_IPV6_MULTICAST(&sin6->sin6_addr, e_addr); 1133 *llsa = (struct sockaddr *)sdl; 1134 return 0; 1135 #endif 1136 1137 default: 1138 /* 1139 * Well, the text isn't quite right, but it's the name 1140 * that counts... 1141 */ 1142 return EAFNOSUPPORT; 1143 } 1144 } 1145 1146 static void* 1147 ether_alloc(u_char type, struct ifnet *ifp) 1148 { 1149 struct arpcom *ac; 1150 1151 ac = malloc(sizeof(struct arpcom), M_ARPCOM, M_WAITOK | M_ZERO); 1152 ac->ac_ifp = ifp; 1153 1154 return (ac); 1155 } 1156 1157 static void 1158 ether_free(void *com, u_char type) 1159 { 1160 1161 free(com, M_ARPCOM); 1162 } 1163 1164 static int 1165 ether_modevent(module_t mod, int type, void *data) 1166 { 1167 1168 switch (type) { 1169 case MOD_LOAD: 1170 if_register_com_alloc(IFT_ETHER, ether_alloc, ether_free); 1171 break; 1172 case MOD_UNLOAD: 1173 if_deregister_com_alloc(IFT_ETHER); 1174 break; 1175 default: 1176 return EOPNOTSUPP; 1177 } 1178 1179 return (0); 1180 } 1181 1182 static moduledata_t ether_mod = { 1183 "ether", 1184 ether_modevent, 1185 0 1186 }; 1187 1188 DECLARE_MODULE(ether, ether_mod, SI_SUB_INIT_IF, SI_ORDER_ANY); 1189 MODULE_VERSION(ether, 1); 1190