if_ethersubr.c revision 153494
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: head/sys/net/if_ethersubr.c 153494 2005-12-17 06:33:51Z thompsa $ 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/mac.h> 45#include <sys/malloc.h> 46#include <sys/module.h> 47#include <sys/mbuf.h> 48#include <sys/random.h> 49#include <sys/socket.h> 50#include <sys/sockio.h> 51#include <sys/sysctl.h> 52 53#include <net/if.h> 54#include <net/if_arp.h> 55#include <net/netisr.h> 56#include <net/route.h> 57#include <net/if_llc.h> 58#include <net/if_dl.h> 59#include <net/if_types.h> 60#include <net/bpf.h> 61#include <net/ethernet.h> 62#include <net/if_bridgevar.h> 63#include <net/if_vlan_var.h> 64 65#if defined(INET) || defined(INET6) 66#include <netinet/in.h> 67#include <netinet/in_var.h> 68#include <netinet/if_ether.h> 69#include <netinet/ip_fw.h> 70#include <netinet/ip_dummynet.h> 71#endif 72#ifdef INET6 73#include <netinet6/nd6.h> 74#endif 75 76#ifdef DEV_CARP 77#include <netinet/ip_carp.h> 78#endif 79 80#ifdef IPX 81#include <netipx/ipx.h> 82#include <netipx/ipx_if.h> 83#endif 84int (*ef_inputp)(struct ifnet*, struct ether_header *eh, struct mbuf *m); 85int (*ef_outputp)(struct ifnet *ifp, struct mbuf **mp, 86 struct sockaddr *dst, short *tp, int *hlen); 87 88#ifdef NETATALK 89#include <netatalk/at.h> 90#include <netatalk/at_var.h> 91#include <netatalk/at_extern.h> 92 93#define llc_snap_org_code llc_un.type_snap.org_code 94#define llc_snap_ether_type llc_un.type_snap.ether_type 95 96extern u_char at_org_code[3]; 97extern u_char aarp_org_code[3]; 98#endif /* NETATALK */ 99 100/* netgraph node hooks for ng_ether(4) */ 101void (*ng_ether_input_p)(struct ifnet *ifp, struct mbuf **mp); 102void (*ng_ether_input_orphan_p)(struct ifnet *ifp, struct mbuf *m); 103int (*ng_ether_output_p)(struct ifnet *ifp, struct mbuf **mp); 104void (*ng_ether_attach_p)(struct ifnet *ifp); 105void (*ng_ether_detach_p)(struct ifnet *ifp); 106 107void (*vlan_input_p)(struct ifnet *, struct mbuf *); 108 109/* if_bridge(4) support */ 110struct mbuf *(*bridge_input_p)(struct ifnet *, struct mbuf *); 111int (*bridge_output_p)(struct ifnet *, struct mbuf *, 112 struct sockaddr *, struct rtentry *); 113void (*bridge_dn_p)(struct mbuf *, struct ifnet *); 114 115static const u_char etherbroadcastaddr[ETHER_ADDR_LEN] = 116 { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff }; 117 118static int ether_resolvemulti(struct ifnet *, struct sockaddr **, 119 struct sockaddr *); 120 121/* XXX: should be in an arp support file, not here */ 122MALLOC_DEFINE(M_ARPCOM, "arpcom", "802.* interface internals"); 123 124#define senderr(e) do { error = (e); goto bad;} while (0) 125 126#if defined(INET) || defined(INET6) 127int 128ether_ipfw_chk(struct mbuf **m0, struct ifnet *dst, 129 struct ip_fw **rule, int shared); 130static int ether_ipfw; 131#endif 132 133/* 134 * Ethernet output routine. 135 * Encapsulate a packet of type family for the local net. 136 * Use trailer local net encapsulation if enough data in first 137 * packet leaves a multiple of 512 bytes of data in remainder. 138 */ 139int 140ether_output(struct ifnet *ifp, struct mbuf *m, 141 struct sockaddr *dst, struct rtentry *rt0) 142{ 143 short type; 144 int error, hdrcmplt = 0; 145 u_char esrc[ETHER_ADDR_LEN], edst[ETHER_ADDR_LEN]; 146 struct ether_header *eh; 147 int loop_copy = 0; 148 int hlen; /* link layer header length */ 149 150#ifdef MAC 151 error = mac_check_ifnet_transmit(ifp, m); 152 if (error) 153 senderr(error); 154#endif 155 156 if (ifp->if_flags & IFF_MONITOR) 157 senderr(ENETDOWN); 158 if (!((ifp->if_flags & IFF_UP) && 159 (ifp->if_drv_flags & IFF_DRV_RUNNING))) 160 senderr(ENETDOWN); 161 162 hlen = ETHER_HDR_LEN; 163 switch (dst->sa_family) { 164#ifdef INET 165 case AF_INET: 166 error = arpresolve(ifp, rt0, m, dst, edst); 167 if (error) 168 return (error == EWOULDBLOCK ? 0 : error); 169 type = htons(ETHERTYPE_IP); 170 break; 171 case AF_ARP: 172 { 173 struct arphdr *ah; 174 ah = mtod(m, struct arphdr *); 175 ah->ar_hrd = htons(ARPHRD_ETHER); 176 177 loop_copy = -1; /* if this is for us, don't do it */ 178 179 switch(ntohs(ah->ar_op)) { 180 case ARPOP_REVREQUEST: 181 case ARPOP_REVREPLY: 182 type = htons(ETHERTYPE_REVARP); 183 break; 184 case ARPOP_REQUEST: 185 case ARPOP_REPLY: 186 default: 187 type = htons(ETHERTYPE_ARP); 188 break; 189 } 190 191 if (m->m_flags & M_BCAST) 192 bcopy(ifp->if_broadcastaddr, edst, ETHER_ADDR_LEN); 193 else 194 bcopy(ar_tha(ah), edst, ETHER_ADDR_LEN); 195 196 } 197 break; 198#endif 199#ifdef INET6 200 case AF_INET6: 201 error = nd6_storelladdr(ifp, rt0, m, dst, (u_char *)edst); 202 if (error) 203 return error; 204 type = htons(ETHERTYPE_IPV6); 205 break; 206#endif 207#ifdef IPX 208 case AF_IPX: 209 if (ef_outputp) { 210 error = ef_outputp(ifp, &m, dst, &type, &hlen); 211 if (error) 212 goto bad; 213 } else 214 type = htons(ETHERTYPE_IPX); 215 bcopy((caddr_t)&(((struct sockaddr_ipx *)dst)->sipx_addr.x_host), 216 (caddr_t)edst, sizeof (edst)); 217 break; 218#endif 219#ifdef NETATALK 220 case AF_APPLETALK: 221 { 222 struct at_ifaddr *aa; 223 224 if ((aa = at_ifawithnet((struct sockaddr_at *)dst)) == NULL) 225 senderr(EHOSTUNREACH); /* XXX */ 226 if (!aarpresolve(ifp, m, (struct sockaddr_at *)dst, edst)) 227 return (0); 228 /* 229 * In the phase 2 case, need to prepend an mbuf for the llc header. 230 */ 231 if ( aa->aa_flags & AFA_PHASE2 ) { 232 struct llc llc; 233 234 M_PREPEND(m, LLC_SNAPFRAMELEN, M_DONTWAIT); 235 if (m == NULL) 236 senderr(ENOBUFS); 237 llc.llc_dsap = llc.llc_ssap = LLC_SNAP_LSAP; 238 llc.llc_control = LLC_UI; 239 bcopy(at_org_code, llc.llc_snap_org_code, sizeof(at_org_code)); 240 llc.llc_snap_ether_type = htons( ETHERTYPE_AT ); 241 bcopy(&llc, mtod(m, caddr_t), LLC_SNAPFRAMELEN); 242 type = htons(m->m_pkthdr.len); 243 hlen = LLC_SNAPFRAMELEN + ETHER_HDR_LEN; 244 } else { 245 type = htons(ETHERTYPE_AT); 246 } 247 break; 248 } 249#endif /* NETATALK */ 250 251 case pseudo_AF_HDRCMPLT: 252 hdrcmplt = 1; 253 eh = (struct ether_header *)dst->sa_data; 254 (void)memcpy(esrc, eh->ether_shost, sizeof (esrc)); 255 /* FALLTHROUGH */ 256 257 case AF_UNSPEC: 258 loop_copy = -1; /* if this is for us, don't do it */ 259 eh = (struct ether_header *)dst->sa_data; 260 (void)memcpy(edst, eh->ether_dhost, sizeof (edst)); 261 type = eh->ether_type; 262 break; 263 264 default: 265 if_printf(ifp, "can't handle af%d\n", dst->sa_family); 266 senderr(EAFNOSUPPORT); 267 } 268 269 /* 270 * Add local net header. If no space in first mbuf, 271 * allocate another. 272 */ 273 M_PREPEND(m, ETHER_HDR_LEN, M_DONTWAIT); 274 if (m == NULL) 275 senderr(ENOBUFS); 276 eh = mtod(m, struct ether_header *); 277 (void)memcpy(&eh->ether_type, &type, 278 sizeof(eh->ether_type)); 279 (void)memcpy(eh->ether_dhost, edst, sizeof (edst)); 280 if (hdrcmplt) 281 (void)memcpy(eh->ether_shost, esrc, 282 sizeof(eh->ether_shost)); 283 else 284 (void)memcpy(eh->ether_shost, IF_LLADDR(ifp), 285 sizeof(eh->ether_shost)); 286 287 /* 288 * Bridges require special output handling. 289 */ 290 if (ifp->if_bridge) { 291 BRIDGE_OUTPUT(ifp, m, error); 292 return (error); 293 } 294 295 /* 296 * If a simplex interface, and the packet is being sent to our 297 * Ethernet address or a broadcast address, loopback a copy. 298 * XXX To make a simplex device behave exactly like a duplex 299 * device, we should copy in the case of sending to our own 300 * ethernet address (thus letting the original actually appear 301 * on the wire). However, we don't do that here for security 302 * reasons and compatibility with the original behavior. 303 */ 304 if ((ifp->if_flags & IFF_SIMPLEX) && (loop_copy != -1) && 305 m_tag_find(m, PACKET_TAG_PF_ROUTED, NULL) == NULL) { 306 int csum_flags = 0; 307 308 if (m->m_pkthdr.csum_flags & CSUM_IP) 309 csum_flags |= (CSUM_IP_CHECKED|CSUM_IP_VALID); 310 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) 311 csum_flags |= (CSUM_DATA_VALID|CSUM_PSEUDO_HDR); 312 313 if ((m->m_flags & M_BCAST) || (loop_copy > 0)) { 314 struct mbuf *n; 315 316 if ((n = m_copy(m, 0, (int)M_COPYALL)) != NULL) { 317 n->m_pkthdr.csum_flags |= csum_flags; 318 if (csum_flags & CSUM_DATA_VALID) 319 n->m_pkthdr.csum_data = 0xffff; 320 (void)if_simloop(ifp, n, dst->sa_family, hlen); 321 } else 322 ifp->if_iqdrops++; 323 } else if (bcmp(eh->ether_dhost, eh->ether_shost, 324 ETHER_ADDR_LEN) == 0) { 325 m->m_pkthdr.csum_flags |= csum_flags; 326 if (csum_flags & CSUM_DATA_VALID) 327 m->m_pkthdr.csum_data = 0xffff; 328 (void) if_simloop(ifp, m, dst->sa_family, hlen); 329 return (0); /* XXX */ 330 } 331 } 332 333#ifdef DEV_CARP 334 if (ifp->if_carp && 335 (error = carp_output(ifp, m, dst, NULL))) 336 goto bad; 337#endif 338 339 /* Handle ng_ether(4) processing, if any */ 340 if (IFP2AC(ifp)->ac_netgraph != NULL) { 341 KASSERT(ng_ether_output_p != NULL, 342 ("ng_ether_output_p is NULL")); 343 if ((error = (*ng_ether_output_p)(ifp, &m)) != 0) { 344bad: if (m != NULL) 345 m_freem(m); 346 return (error); 347 } 348 if (m == NULL) 349 return (0); 350 } 351 352 /* Continue with link-layer output */ 353 return ether_output_frame(ifp, m); 354} 355 356/* 357 * Ethernet link layer output routine to send a raw frame to the device. 358 * 359 * This assumes that the 14 byte Ethernet header is present and contiguous 360 * in the first mbuf (if BRIDGE'ing). 361 */ 362int 363ether_output_frame(struct ifnet *ifp, struct mbuf *m) 364{ 365 int error; 366#if defined(INET) || defined(INET6) 367 struct ip_fw *rule = ip_dn_claim_rule(m); 368 369 if (IPFW_LOADED && ether_ipfw != 0) { 370 if (ether_ipfw_chk(&m, ifp, &rule, 0) == 0) { 371 if (m) { 372 m_freem(m); 373 return EACCES; /* pkt dropped */ 374 } else 375 return 0; /* consumed e.g. in a pipe */ 376 } 377 } 378#endif 379 380 /* 381 * Queue message on interface, update output statistics if 382 * successful, and start output if interface not yet active. 383 */ 384 IFQ_HANDOFF(ifp, m, error); 385 return (error); 386} 387 388#if defined(INET) || defined(INET6) 389/* 390 * ipfw processing for ethernet packets (in and out). 391 * The second parameter is NULL from ether_demux, and ifp from 392 * ether_output_frame. 393 */ 394int 395ether_ipfw_chk(struct mbuf **m0, struct ifnet *dst, 396 struct ip_fw **rule, int shared) 397{ 398 struct ether_header *eh; 399 struct ether_header save_eh; 400 struct mbuf *m; 401 int i; 402 struct ip_fw_args args; 403 404 if (*rule != NULL && fw_one_pass) 405 return 1; /* dummynet packet, already partially processed */ 406 407 /* 408 * I need some amt of data to be contiguous, and in case others need 409 * the packet (shared==1) also better be in the first mbuf. 410 */ 411 m = *m0; 412 i = min( m->m_pkthdr.len, max_protohdr); 413 if ( shared || m->m_len < i) { 414 m = m_pullup(m, i); 415 if (m == NULL) { 416 *m0 = m; 417 return 0; 418 } 419 } 420 eh = mtod(m, struct ether_header *); 421 save_eh = *eh; /* save copy for restore below */ 422 m_adj(m, ETHER_HDR_LEN); /* strip ethernet header */ 423 424 args.m = m; /* the packet we are looking at */ 425 args.oif = dst; /* destination, if any */ 426 args.rule = *rule; /* matching rule to restart */ 427 args.next_hop = NULL; /* we do not support forward yet */ 428 args.eh = &save_eh; /* MAC header for bridged/MAC packets */ 429 i = ip_fw_chk_ptr(&args); 430 m = args.m; 431 if (m != NULL) { 432 /* 433 * Restore Ethernet header, as needed, in case the 434 * mbuf chain was replaced by ipfw. 435 */ 436 M_PREPEND(m, ETHER_HDR_LEN, M_DONTWAIT); 437 if (m == NULL) { 438 *m0 = m; 439 return 0; 440 } 441 if (eh != mtod(m, struct ether_header *)) 442 bcopy(&save_eh, mtod(m, struct ether_header *), 443 ETHER_HDR_LEN); 444 } 445 *m0 = m; 446 *rule = args.rule; 447 448 if (i == IP_FW_DENY) /* drop */ 449 return 0; 450 451 KASSERT(m != NULL, ("ether_ipfw_chk: m is NULL")); 452 453 if (i == IP_FW_PASS) /* a PASS rule. */ 454 return 1; 455 456 if (DUMMYNET_LOADED && (i == IP_FW_DUMMYNET)) { 457 /* 458 * Pass the pkt to dummynet, which consumes it. 459 * If shared, make a copy and keep the original. 460 */ 461 if (shared) { 462 m = m_copypacket(m, M_DONTWAIT); 463 if (m == NULL) 464 return 0; 465 } else { 466 /* 467 * Pass the original to dummynet and 468 * nothing back to the caller 469 */ 470 *m0 = NULL ; 471 } 472 ip_dn_io_ptr(m, dst ? DN_TO_ETH_OUT: DN_TO_ETH_DEMUX, &args); 473 return 0; 474 } 475 /* 476 * XXX at some point add support for divert/forward actions. 477 * If none of the above matches, we have to drop the pkt. 478 */ 479 return 0; 480} 481#endif 482 483/* 484 * Process a received Ethernet packet; the packet is in the 485 * mbuf chain m with the ethernet header at the front. 486 */ 487static void 488ether_input(struct ifnet *ifp, struct mbuf *m) 489{ 490 struct ether_header *eh; 491 u_short etype; 492 493 /* 494 * Do consistency checks to verify assumptions 495 * made by code past this point. 496 */ 497 if ((m->m_flags & M_PKTHDR) == 0) { 498 if_printf(ifp, "discard frame w/o packet header\n"); 499 ifp->if_ierrors++; 500 m_freem(m); 501 return; 502 } 503 if (m->m_len < ETHER_HDR_LEN) { 504 /* XXX maybe should pullup? */ 505 if_printf(ifp, "discard frame w/o leading ethernet " 506 "header (len %u pkt len %u)\n", 507 m->m_len, m->m_pkthdr.len); 508 ifp->if_ierrors++; 509 m_freem(m); 510 return; 511 } 512 eh = mtod(m, struct ether_header *); 513 etype = ntohs(eh->ether_type); 514 if (m->m_pkthdr.len > 515 ETHER_MAX_FRAME(ifp, etype, m->m_flags & M_HASFCS)) { 516 if_printf(ifp, "discard oversize frame " 517 "(ether type %x flags %x len %u > max %lu)\n", 518 etype, m->m_flags, m->m_pkthdr.len, 519 ETHER_MAX_FRAME(ifp, etype, 520 m->m_flags & M_HASFCS)); 521 ifp->if_ierrors++; 522 m_freem(m); 523 return; 524 } 525 if (m->m_pkthdr.rcvif == NULL) { 526 if_printf(ifp, "discard frame w/o interface pointer\n"); 527 ifp->if_ierrors++; 528 m_freem(m); 529 return; 530 } 531#ifdef DIAGNOSTIC 532 if (m->m_pkthdr.rcvif != ifp) { 533 if_printf(ifp, "Warning, frame marked as received on %s\n", 534 m->m_pkthdr.rcvif->if_xname); 535 } 536#endif 537 538#ifdef MAC 539 /* 540 * Tag the mbuf with an appropriate MAC label before any other 541 * consumers can get to it. 542 */ 543 mac_create_mbuf_from_ifnet(ifp, m); 544#endif 545 546 /* 547 * Give bpf a chance at the packet. 548 */ 549 BPF_MTAP(ifp, m); 550 551 if (ifp->if_flags & IFF_MONITOR) { 552 /* 553 * Interface marked for monitoring; discard packet. 554 */ 555 m_freem(m); 556 return; 557 } 558 559 /* If the CRC is still on the packet, trim it off. */ 560 if (m->m_flags & M_HASFCS) { 561 m_adj(m, -ETHER_CRC_LEN); 562 m->m_flags &= ~M_HASFCS; 563 } 564 565 ifp->if_ibytes += m->m_pkthdr.len; 566 567 /* Handle ng_ether(4) processing, if any */ 568 if (IFP2AC(ifp)->ac_netgraph != NULL) { 569 KASSERT(ng_ether_input_p != NULL, 570 ("ng_ether_input_p is NULL")); 571 (*ng_ether_input_p)(ifp, &m); 572 if (m == NULL) 573 return; 574 } 575 576 /* 577 * Tap the packet off here for a bridge. bridge_input() 578 * will return NULL if it has consumed the packet, otherwise 579 * it gets processed as normal. Note that bridge_input() 580 * will always return the original packet if we need to 581 * process it locally. 582 * 583 * XXX: When changing the below block, please also look 584 * at the src/sys/netgraph/ng_ether.c:ng_ether_rcv_upper() 585 */ 586 if (ifp->if_bridge) { 587 BRIDGE_INPUT(ifp, m); 588 if (m == NULL) 589 return; 590 } 591 592 /* First chunk of an mbuf contains good entropy */ 593 if (harvest.ethernet) 594 random_harvest(m, 16, 3, 0, RANDOM_NET); 595 ether_demux(ifp, m); 596} 597 598/* 599 * Upper layer processing for a received Ethernet packet. 600 */ 601void 602ether_demux(struct ifnet *ifp, struct mbuf *m) 603{ 604 struct ether_header *eh; 605 int isr; 606 u_short ether_type; 607#if defined(NETATALK) 608 struct llc *l; 609#endif 610#if defined(INET) || defined(INET6) 611 struct ip_fw *rule = ip_dn_claim_rule(m); 612#endif 613 614 KASSERT(ifp != NULL, ("ether_demux: NULL interface pointer")); 615 616 eh = mtod(m, struct ether_header *); 617 ether_type = ntohs(eh->ether_type); 618 619#if defined(INET) || defined(INET6) 620 if (rule) /* packet was already bridged */ 621 goto post_stats; 622#endif 623 624 if (!(ifp->if_bridge) && 625 !((ether_type == ETHERTYPE_VLAN || m->m_flags & M_VLANTAG) && 626 ifp->if_nvlans > 0)) { 627#ifdef DEV_CARP 628 /* 629 * XXX: Okay, we need to call carp_forus() and - if it is for 630 * us jump over code that does the normal check 631 * "IF_LLADDR(ifp) == ether_dhost". The check sequence is a bit 632 * different from OpenBSD, so we jump over as few code as 633 * possible, to catch _all_ sanity checks. This needs 634 * evaluation, to see if the carp ether_dhost values break any 635 * of these checks! 636 */ 637 if (ifp->if_carp && carp_forus(ifp->if_carp, eh->ether_dhost)) 638 goto pre_stats; 639#endif 640 /* 641 * Discard packet if upper layers shouldn't see it because it 642 * was unicast to a different Ethernet address. If the driver 643 * is working properly, then this situation can only happen 644 * when the interface is in promiscuous mode. 645 * 646 * If VLANs are active, and this packet has a VLAN tag, do 647 * not drop it here but pass it on to the VLAN layer, to 648 * give them a chance to consider it as well (e. g. in case 649 * bridging is only active on a VLAN). They will drop it if 650 * it's undesired. 651 */ 652 if ((ifp->if_flags & IFF_PROMISC) != 0 653 && !ETHER_IS_MULTICAST(eh->ether_dhost) 654 && bcmp(eh->ether_dhost, 655 IF_LLADDR(ifp), ETHER_ADDR_LEN) != 0 656 && (ifp->if_flags & IFF_PPROMISC) == 0) { 657 m_freem(m); 658 return; 659 } 660 } 661 662#ifdef DEV_CARP 663pre_stats: 664#endif 665 /* Discard packet if interface is not up */ 666 if ((ifp->if_flags & IFF_UP) == 0) { 667 m_freem(m); 668 return; 669 } 670 if (ETHER_IS_MULTICAST(eh->ether_dhost)) { 671 if (bcmp(etherbroadcastaddr, eh->ether_dhost, 672 sizeof(etherbroadcastaddr)) == 0) 673 m->m_flags |= M_BCAST; 674 else 675 m->m_flags |= M_MCAST; 676 } 677 if (m->m_flags & (M_BCAST|M_MCAST)) 678 ifp->if_imcasts++; 679 680#if defined(INET) || defined(INET6) 681post_stats: 682 if (IPFW_LOADED && ether_ipfw != 0) { 683 if (ether_ipfw_chk(&m, NULL, &rule, 0) == 0) { 684 if (m) 685 m_freem(m); 686 return; 687 } 688 } 689#endif 690 691 /* 692 * Check to see if the device performed the VLAN decapsulation and 693 * provided us with the tag. 694 */ 695 if (m->m_flags & M_VLANTAG) { 696 /* 697 * If no VLANs are configured, drop. 698 */ 699 if (ifp->if_nvlans == 0) { 700 ifp->if_noproto++; 701 m_freem(m); 702 return; 703 } 704 /* 705 * vlan_input() will either recursively call ether_input() 706 * or drop the packet. 707 */ 708 KASSERT(vlan_input_p != NULL,("ether_input: VLAN not loaded!")); 709 (*vlan_input_p)(ifp, m); 710 return; 711 } 712 713 /* 714 * Handle protocols that expect to have the Ethernet header 715 * (and possibly FCS) intact. 716 */ 717 switch (ether_type) { 718 case ETHERTYPE_VLAN: 719 if (ifp->if_nvlans != 0) { 720 KASSERT(vlan_input_p,("ether_input: VLAN not loaded!")); 721 (*vlan_input_p)(ifp, m); 722 } else { 723 ifp->if_noproto++; 724 m_freem(m); 725 } 726 return; 727 } 728 729 /* Strip off Ethernet header. */ 730 m_adj(m, ETHER_HDR_LEN); 731 732 /* If the CRC is still on the packet, trim it off. */ 733 if (m->m_flags & M_HASFCS) { 734 m_adj(m, -ETHER_CRC_LEN); 735 m->m_flags &= ~M_HASFCS; 736 } 737 738 /* Reset layer specific mbuf flags to avoid confusing upper layers. */ 739 m->m_flags &= ~(M_PROTOFLAGS); 740 741 switch (ether_type) { 742#ifdef INET 743 case ETHERTYPE_IP: 744 if (ip_fastforward(m)) 745 return; 746 isr = NETISR_IP; 747 break; 748 749 case ETHERTYPE_ARP: 750 if (ifp->if_flags & IFF_NOARP) { 751 /* Discard packet if ARP is disabled on interface */ 752 m_freem(m); 753 return; 754 } 755 isr = NETISR_ARP; 756 break; 757#endif 758#ifdef IPX 759 case ETHERTYPE_IPX: 760 if (ef_inputp && ef_inputp(ifp, eh, m) == 0) 761 return; 762 isr = NETISR_IPX; 763 break; 764#endif 765#ifdef INET6 766 case ETHERTYPE_IPV6: 767 isr = NETISR_IPV6; 768 break; 769#endif 770#ifdef NETATALK 771 case ETHERTYPE_AT: 772 isr = NETISR_ATALK1; 773 break; 774 case ETHERTYPE_AARP: 775 isr = NETISR_AARP; 776 break; 777#endif /* NETATALK */ 778 default: 779#ifdef IPX 780 if (ef_inputp && ef_inputp(ifp, eh, m) == 0) 781 return; 782#endif /* IPX */ 783#if defined(NETATALK) 784 if (ether_type > ETHERMTU) 785 goto discard; 786 l = mtod(m, struct llc *); 787 if (l->llc_dsap == LLC_SNAP_LSAP && 788 l->llc_ssap == LLC_SNAP_LSAP && 789 l->llc_control == LLC_UI) { 790 if (bcmp(&(l->llc_snap_org_code)[0], at_org_code, 791 sizeof(at_org_code)) == 0 && 792 ntohs(l->llc_snap_ether_type) == ETHERTYPE_AT) { 793 m_adj(m, LLC_SNAPFRAMELEN); 794 isr = NETISR_ATALK2; 795 break; 796 } 797 if (bcmp(&(l->llc_snap_org_code)[0], aarp_org_code, 798 sizeof(aarp_org_code)) == 0 && 799 ntohs(l->llc_snap_ether_type) == ETHERTYPE_AARP) { 800 m_adj(m, LLC_SNAPFRAMELEN); 801 isr = NETISR_AARP; 802 break; 803 } 804 } 805#endif /* NETATALK */ 806 goto discard; 807 } 808 netisr_dispatch(isr, m); 809 return; 810 811discard: 812 /* 813 * Packet is to be discarded. If netgraph is present, 814 * hand the packet to it for last chance processing; 815 * otherwise dispose of it. 816 */ 817 if (IFP2AC(ifp)->ac_netgraph != NULL) { 818 KASSERT(ng_ether_input_orphan_p != NULL, 819 ("ng_ether_input_orphan_p is NULL")); 820 /* 821 * Put back the ethernet header so netgraph has a 822 * consistent view of inbound packets. 823 */ 824 M_PREPEND(m, ETHER_HDR_LEN, M_DONTWAIT); 825 (*ng_ether_input_orphan_p)(ifp, m); 826 return; 827 } 828 m_freem(m); 829} 830 831/* 832 * Convert Ethernet address to printable (loggable) representation. 833 * This routine is for compatibility; it's better to just use 834 * 835 * printf("%6D", <pointer to address>, ":"); 836 * 837 * since there's no static buffer involved. 838 */ 839char * 840ether_sprintf(const u_char *ap) 841{ 842 static char etherbuf[18]; 843 snprintf(etherbuf, sizeof (etherbuf), "%6D", ap, ":"); 844 return (etherbuf); 845} 846 847/* 848 * Perform common duties while attaching to interface list 849 */ 850void 851ether_ifattach(struct ifnet *ifp, const u_int8_t *lla) 852{ 853 int i; 854 struct ifaddr *ifa; 855 struct sockaddr_dl *sdl; 856 857 ifp->if_addrlen = ETHER_ADDR_LEN; 858 ifp->if_hdrlen = ETHER_HDR_LEN; 859 if_attach(ifp); 860 ifp->if_mtu = ETHERMTU; 861 ifp->if_output = ether_output; 862 ifp->if_input = ether_input; 863 ifp->if_resolvemulti = ether_resolvemulti; 864 if (ifp->if_baudrate == 0) 865 ifp->if_baudrate = IF_Mbps(10); /* just a default */ 866 ifp->if_broadcastaddr = etherbroadcastaddr; 867 868 ifa = ifp->if_addr; 869 KASSERT(ifa != NULL, ("%s: no lladdr!\n", __func__)); 870 sdl = (struct sockaddr_dl *)ifa->ifa_addr; 871 sdl->sdl_type = IFT_ETHER; 872 sdl->sdl_alen = ifp->if_addrlen; 873 bcopy(lla, LLADDR(sdl), ifp->if_addrlen); 874 875 bpfattach(ifp, DLT_EN10MB, ETHER_HDR_LEN); 876 if (ng_ether_attach_p != NULL) 877 (*ng_ether_attach_p)(ifp); 878 879 /* Announce Ethernet MAC address if non-zero. */ 880 for (i = 0; i < ifp->if_addrlen; i++) 881 if (lla[i] != 0) 882 break; 883 if (i != ifp->if_addrlen) 884 if_printf(ifp, "Ethernet address: %6D\n", lla, ":"); 885 if (debug_mpsafenet && (ifp->if_flags & IFF_NEEDSGIANT) != 0) 886 if_printf(ifp, "if_start running deferred for Giant\n"); 887} 888 889/* 890 * Perform common duties while detaching an Ethernet interface 891 */ 892void 893ether_ifdetach(struct ifnet *ifp) 894{ 895 if (IFP2AC(ifp)->ac_netgraph != NULL) { 896 KASSERT(ng_ether_detach_p != NULL, 897 ("ng_ether_detach_p is NULL")); 898 (*ng_ether_detach_p)(ifp); 899 } 900 901 bpfdetach(ifp); 902 if_detach(ifp); 903} 904 905SYSCTL_DECL(_net_link); 906SYSCTL_NODE(_net_link, IFT_ETHER, ether, CTLFLAG_RW, 0, "Ethernet"); 907#if defined(INET) || defined(INET6) 908SYSCTL_INT(_net_link_ether, OID_AUTO, ipfw, CTLFLAG_RW, 909 ðer_ipfw,0,"Pass ether pkts through firewall"); 910#endif 911 912#if 0 913/* 914 * This is for reference. We have a table-driven version 915 * of the little-endian crc32 generator, which is faster 916 * than the double-loop. 917 */ 918uint32_t 919ether_crc32_le(const uint8_t *buf, size_t len) 920{ 921 size_t i; 922 uint32_t crc; 923 int bit; 924 uint8_t data; 925 926 crc = 0xffffffff; /* initial value */ 927 928 for (i = 0; i < len; i++) { 929 for (data = *buf++, bit = 0; bit < 8; bit++, data >>= 1) 930 carry = (crc ^ data) & 1; 931 crc >>= 1; 932 if (carry) 933 crc = (crc ^ ETHER_CRC_POLY_LE); 934 } 935 936 return (crc); 937} 938#else 939uint32_t 940ether_crc32_le(const uint8_t *buf, size_t len) 941{ 942 static const uint32_t crctab[] = { 943 0x00000000, 0x1db71064, 0x3b6e20c8, 0x26d930ac, 944 0x76dc4190, 0x6b6b51f4, 0x4db26158, 0x5005713c, 945 0xedb88320, 0xf00f9344, 0xd6d6a3e8, 0xcb61b38c, 946 0x9b64c2b0, 0x86d3d2d4, 0xa00ae278, 0xbdbdf21c 947 }; 948 size_t i; 949 uint32_t crc; 950 951 crc = 0xffffffff; /* initial value */ 952 953 for (i = 0; i < len; i++) { 954 crc ^= buf[i]; 955 crc = (crc >> 4) ^ crctab[crc & 0xf]; 956 crc = (crc >> 4) ^ crctab[crc & 0xf]; 957 } 958 959 return (crc); 960} 961#endif 962 963uint32_t 964ether_crc32_be(const uint8_t *buf, size_t len) 965{ 966 size_t i; 967 uint32_t crc, carry; 968 int bit; 969 uint8_t data; 970 971 crc = 0xffffffff; /* initial value */ 972 973 for (i = 0; i < len; i++) { 974 for (data = *buf++, bit = 0; bit < 8; bit++, data >>= 1) { 975 carry = ((crc & 0x80000000) ? 1 : 0) ^ (data & 0x01); 976 crc <<= 1; 977 if (carry) 978 crc = (crc ^ ETHER_CRC_POLY_BE) | carry; 979 } 980 } 981 982 return (crc); 983} 984 985int 986ether_ioctl(struct ifnet *ifp, int command, caddr_t data) 987{ 988 struct ifaddr *ifa = (struct ifaddr *) data; 989 struct ifreq *ifr = (struct ifreq *) data; 990 int error = 0; 991 992 switch (command) { 993 case SIOCSIFADDR: 994 ifp->if_flags |= IFF_UP; 995 996 switch (ifa->ifa_addr->sa_family) { 997#ifdef INET 998 case AF_INET: 999 ifp->if_init(ifp->if_softc); /* before arpwhohas */ 1000 arp_ifinit(ifp, ifa); 1001 break; 1002#endif 1003#ifdef IPX 1004 /* 1005 * XXX - This code is probably wrong 1006 */ 1007 case AF_IPX: 1008 { 1009 struct ipx_addr *ina = &(IA_SIPX(ifa)->sipx_addr); 1010 1011 if (ipx_nullhost(*ina)) 1012 ina->x_host = 1013 *(union ipx_host *) 1014 IF_LLADDR(ifp); 1015 else { 1016 bcopy((caddr_t) ina->x_host.c_host, 1017 (caddr_t) IF_LLADDR(ifp), 1018 ETHER_ADDR_LEN); 1019 } 1020 1021 /* 1022 * Set new address 1023 */ 1024 ifp->if_init(ifp->if_softc); 1025 break; 1026 } 1027#endif 1028 default: 1029 ifp->if_init(ifp->if_softc); 1030 break; 1031 } 1032 break; 1033 1034 case SIOCGIFADDR: 1035 { 1036 struct sockaddr *sa; 1037 1038 sa = (struct sockaddr *) & ifr->ifr_data; 1039 bcopy(IF_LLADDR(ifp), 1040 (caddr_t) sa->sa_data, ETHER_ADDR_LEN); 1041 } 1042 break; 1043 1044 case SIOCSIFMTU: 1045 /* 1046 * Set the interface MTU. 1047 */ 1048 if (ifr->ifr_mtu > ETHERMTU) { 1049 error = EINVAL; 1050 } else { 1051 ifp->if_mtu = ifr->ifr_mtu; 1052 } 1053 break; 1054 default: 1055 error = EINVAL; /* XXX netbsd has ENOTTY??? */ 1056 break; 1057 } 1058 return (error); 1059} 1060 1061static int 1062ether_resolvemulti(struct ifnet *ifp, struct sockaddr **llsa, 1063 struct sockaddr *sa) 1064{ 1065 struct sockaddr_dl *sdl; 1066#ifdef INET 1067 struct sockaddr_in *sin; 1068#endif 1069#ifdef INET6 1070 struct sockaddr_in6 *sin6; 1071#endif 1072 u_char *e_addr; 1073 1074 switch(sa->sa_family) { 1075 case AF_LINK: 1076 /* 1077 * No mapping needed. Just check that it's a valid MC address. 1078 */ 1079 sdl = (struct sockaddr_dl *)sa; 1080 e_addr = LLADDR(sdl); 1081 if (!ETHER_IS_MULTICAST(e_addr)) 1082 return EADDRNOTAVAIL; 1083 *llsa = 0; 1084 return 0; 1085 1086#ifdef INET 1087 case AF_INET: 1088 sin = (struct sockaddr_in *)sa; 1089 if (!IN_MULTICAST(ntohl(sin->sin_addr.s_addr))) 1090 return EADDRNOTAVAIL; 1091 MALLOC(sdl, struct sockaddr_dl *, sizeof *sdl, M_IFMADDR, 1092 M_NOWAIT|M_ZERO); 1093 if (sdl == NULL) 1094 return ENOMEM; 1095 sdl->sdl_len = sizeof *sdl; 1096 sdl->sdl_family = AF_LINK; 1097 sdl->sdl_index = ifp->if_index; 1098 sdl->sdl_type = IFT_ETHER; 1099 sdl->sdl_alen = ETHER_ADDR_LEN; 1100 e_addr = LLADDR(sdl); 1101 ETHER_MAP_IP_MULTICAST(&sin->sin_addr, e_addr); 1102 *llsa = (struct sockaddr *)sdl; 1103 return 0; 1104#endif 1105#ifdef INET6 1106 case AF_INET6: 1107 sin6 = (struct sockaddr_in6 *)sa; 1108 if (IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr)) { 1109 /* 1110 * An IP6 address of 0 means listen to all 1111 * of the Ethernet multicast address used for IP6. 1112 * (This is used for multicast routers.) 1113 */ 1114 ifp->if_flags |= IFF_ALLMULTI; 1115 *llsa = 0; 1116 return 0; 1117 } 1118 if (!IN6_IS_ADDR_MULTICAST(&sin6->sin6_addr)) 1119 return EADDRNOTAVAIL; 1120 MALLOC(sdl, struct sockaddr_dl *, sizeof *sdl, M_IFMADDR, 1121 M_NOWAIT|M_ZERO); 1122 if (sdl == NULL) 1123 return (ENOMEM); 1124 sdl->sdl_len = sizeof *sdl; 1125 sdl->sdl_family = AF_LINK; 1126 sdl->sdl_index = ifp->if_index; 1127 sdl->sdl_type = IFT_ETHER; 1128 sdl->sdl_alen = ETHER_ADDR_LEN; 1129 e_addr = LLADDR(sdl); 1130 ETHER_MAP_IPV6_MULTICAST(&sin6->sin6_addr, e_addr); 1131 *llsa = (struct sockaddr *)sdl; 1132 return 0; 1133#endif 1134 1135 default: 1136 /* 1137 * Well, the text isn't quite right, but it's the name 1138 * that counts... 1139 */ 1140 return EAFNOSUPPORT; 1141 } 1142} 1143 1144static void* 1145ether_alloc(u_char type, struct ifnet *ifp) 1146{ 1147 struct arpcom *ac; 1148 1149 ac = malloc(sizeof(struct arpcom), M_ARPCOM, M_WAITOK | M_ZERO); 1150 ac->ac_ifp = ifp; 1151 1152 return (ac); 1153} 1154 1155static void 1156ether_free(void *com, u_char type) 1157{ 1158 1159 free(com, M_ARPCOM); 1160} 1161 1162static int 1163ether_modevent(module_t mod, int type, void *data) 1164{ 1165 1166 switch (type) { 1167 case MOD_LOAD: 1168 if_register_com_alloc(IFT_ETHER, ether_alloc, ether_free); 1169 break; 1170 case MOD_UNLOAD: 1171 if_deregister_com_alloc(IFT_ETHER); 1172 break; 1173 default: 1174 return EOPNOTSUPP; 1175 } 1176 1177 return (0); 1178} 1179 1180static moduledata_t ether_mod = { 1181 "ether", 1182 ether_modevent, 1183 0 1184}; 1185 1186DECLARE_MODULE(ether, ether_mod, SI_SUB_INIT_IF, SI_ORDER_ANY); 1187MODULE_VERSION(ether, 1); 1188