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/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 84 int (*ef_inputp)(struct ifnet*, struct ether_header *eh, struct mbuf *m); 85 int (*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 96 extern u_char at_org_code[3]; 97 extern u_char aarp_org_code[3]; 98 #endif /* NETATALK */ 99 100 /* netgraph node hooks for ng_ether(4) */ 101 void (*ng_ether_input_p)(struct ifnet *ifp, struct mbuf **mp); 102 void (*ng_ether_input_orphan_p)(struct ifnet *ifp, struct mbuf *m); 103 int (*ng_ether_output_p)(struct ifnet *ifp, struct mbuf **mp); 104 void (*ng_ether_attach_p)(struct ifnet *ifp); 105 void (*ng_ether_detach_p)(struct ifnet *ifp); 106 107 void (*vlan_input_p)(struct ifnet *, struct mbuf *); 108 109 /* if_bridge(4) support */ 110 struct mbuf *(*bridge_input_p)(struct ifnet *, struct mbuf *); 111 int (*bridge_output_p)(struct ifnet *, struct mbuf *, 112 struct sockaddr *, struct rtentry *); 113 void (*bridge_dn_p)(struct mbuf *, struct ifnet *); 114 115 static const u_char etherbroadcastaddr[ETHER_ADDR_LEN] = 116 { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff }; 117 118 static int ether_resolvemulti(struct ifnet *, struct sockaddr **, 119 struct sockaddr *); 120 121 /* XXX: should be in an arp support file, not here */ 122 MALLOC_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) 127 int 128 ether_ipfw_chk(struct mbuf **m0, struct ifnet *dst, 129 struct ip_fw **rule, int shared); 130 static 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 */ 139 int 140 ether_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 = 1; 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 = 0; /* 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 = 0; /* 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 && 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) { 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) { 344 bad: 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 */ 362 int 363 ether_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 */ 394 int 395 ether_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 args.inp = NULL; /* used by ipfw uid/gid/jail rules */ 430 i = ip_fw_chk_ptr(&args); 431 m = args.m; 432 if (m != NULL) { 433 /* 434 * Restore Ethernet header, as needed, in case the 435 * mbuf chain was replaced by ipfw. 436 */ 437 M_PREPEND(m, ETHER_HDR_LEN, M_DONTWAIT); 438 if (m == NULL) { 439 *m0 = m; 440 return 0; 441 } 442 if (eh != mtod(m, struct ether_header *)) 443 bcopy(&save_eh, mtod(m, struct ether_header *), 444 ETHER_HDR_LEN); 445 } 446 *m0 = m; 447 *rule = args.rule; 448 449 if (i == IP_FW_DENY) /* drop */ 450 return 0; 451 452 KASSERT(m != NULL, ("ether_ipfw_chk: m is NULL")); 453 454 if (i == IP_FW_PASS) /* a PASS rule. */ 455 return 1; 456 457 if (DUMMYNET_LOADED && (i == IP_FW_DUMMYNET)) { 458 /* 459 * Pass the pkt to dummynet, which consumes it. 460 * If shared, make a copy and keep the original. 461 */ 462 if (shared) { 463 m = m_copypacket(m, M_DONTWAIT); 464 if (m == NULL) 465 return 0; 466 } else { 467 /* 468 * Pass the original to dummynet and 469 * nothing back to the caller 470 */ 471 *m0 = NULL ; 472 } 473 ip_dn_io_ptr(m, dst ? DN_TO_ETH_OUT: DN_TO_ETH_DEMUX, &args); 474 return 0; 475 } 476 /* 477 * XXX at some point add support for divert/forward actions. 478 * If none of the above matches, we have to drop the pkt. 479 */ 480 return 0; 481 } 482 #endif 483 484 /* 485 * Process a received Ethernet packet; the packet is in the 486 * mbuf chain m with the ethernet header at the front. 487 */ 488 static void 489 ether_input(struct ifnet *ifp, struct mbuf *m) 490 { 491 struct ether_header *eh; 492 u_short etype; 493 494 /* 495 * Do consistency checks to verify assumptions 496 * made by code past this point. 497 */ 498 if ((m->m_flags & M_PKTHDR) == 0) { 499 if_printf(ifp, "discard frame w/o packet header\n"); 500 ifp->if_ierrors++; 501 m_freem(m); 502 return; 503 } 504 if (m->m_len < ETHER_HDR_LEN) { 505 /* XXX maybe should pullup? */ 506 if_printf(ifp, "discard frame w/o leading ethernet " 507 "header (len %u pkt len %u)\n", 508 m->m_len, m->m_pkthdr.len); 509 ifp->if_ierrors++; 510 m_freem(m); 511 return; 512 } 513 eh = mtod(m, struct ether_header *); 514 etype = ntohs(eh->ether_type); 515 if (m->m_pkthdr.len > 516 ETHER_MAX_FRAME(ifp, etype, m->m_flags & M_HASFCS)) { 517 if_printf(ifp, "discard oversize frame " 518 "(ether type %x flags %x len %u > max %lu)\n", 519 etype, m->m_flags, m->m_pkthdr.len, 520 ETHER_MAX_FRAME(ifp, etype, 521 m->m_flags & M_HASFCS)); 522 ifp->if_ierrors++; 523 m_freem(m); 524 return; 525 } 526 if (m->m_pkthdr.rcvif == NULL) { 527 if_printf(ifp, "discard frame w/o interface pointer\n"); 528 ifp->if_ierrors++; 529 m_freem(m); 530 return; 531 } 532 #ifdef DIAGNOSTIC 533 if (m->m_pkthdr.rcvif != ifp) { 534 if_printf(ifp, "Warning, frame marked as received on %s\n", 535 m->m_pkthdr.rcvif->if_xname); 536 } 537 #endif 538 539 #ifdef MAC 540 /* 541 * Tag the mbuf with an appropriate MAC label before any other 542 * consumers can get to it. 543 */ 544 mac_create_mbuf_from_ifnet(ifp, m); 545 #endif 546 547 /* 548 * Give bpf a chance at the packet. 549 */ 550 BPF_MTAP(ifp, m); 551 552 /* If the CRC is still on the packet, trim it off. */ 553 if (m->m_flags & M_HASFCS) { 554 m_adj(m, -ETHER_CRC_LEN); 555 m->m_flags &= ~M_HASFCS; 556 } 557 558 ifp->if_ibytes += m->m_pkthdr.len; 559 560 if (ifp->if_flags & IFF_MONITOR) { 561 /* 562 * Interface marked for monitoring; discard packet. 563 */ 564 m_freem(m); 565 return; 566 } 567 568 /* Handle ng_ether(4) processing, if any */ 569 if (IFP2AC(ifp)->ac_netgraph != NULL) { 570 KASSERT(ng_ether_input_p != NULL, 571 ("ng_ether_input_p is NULL")); 572 (*ng_ether_input_p)(ifp, &m); 573 if (m == NULL) 574 return; 575 } 576 577 /* 578 * Tap the packet off here for a bridge. bridge_input() 579 * will return NULL if it has consumed the packet, otherwise 580 * it gets processed as normal. Note that bridge_input() 581 * will always return the original packet if we need to 582 * process it locally. 583 * 584 * XXX: When changing the below block, please also look 585 * at the src/sys/netgraph/ng_ether.c:ng_ether_rcv_upper() 586 */ 587 if (ifp->if_bridge) { 588 BRIDGE_INPUT(ifp, m); 589 if (m == NULL) 590 return; 591 } 592 593 /* First chunk of an mbuf contains good entropy */ 594 if (harvest.ethernet) 595 random_harvest(m, 16, 3, 0, RANDOM_NET); 596 ether_demux(ifp, m); 597 } 598 599 /* 600 * Upper layer processing for a received Ethernet packet. 601 */ 602 void 603 ether_demux(struct ifnet *ifp, struct mbuf *m) 604 { 605 struct ether_header *eh; 606 int isr; 607 u_short ether_type; 608 #if defined(NETATALK) 609 struct llc *l; 610 #endif 611 #if defined(INET) || defined(INET6) 612 struct ip_fw *rule = ip_dn_claim_rule(m); 613 #endif 614 615 KASSERT(ifp != NULL, ("ether_demux: NULL interface pointer")); 616 617 eh = mtod(m, struct ether_header *); 618 ether_type = ntohs(eh->ether_type); 619 620 #if defined(INET) || defined(INET6) 621 if (rule) /* packet was already bridged */ 622 goto post_stats; 623 #endif 624 625 if (!(ifp->if_bridge) && 626 !((ether_type == ETHERTYPE_VLAN || m->m_flags & M_VLANTAG) && 627 ifp->if_vlantrunk != NULL)) { 628 #ifdef DEV_CARP 629 /* 630 * XXX: Okay, we need to call carp_forus() and - if it is for 631 * us jump over code that does the normal check 632 * "IF_LLADDR(ifp) == ether_dhost". The check sequence is a bit 633 * different from OpenBSD, so we jump over as few code as 634 * possible, to catch _all_ sanity checks. This needs 635 * evaluation, to see if the carp ether_dhost values break any 636 * of these checks! 637 */ 638 if (ifp->if_carp && carp_forus(ifp->if_carp, eh->ether_dhost)) 639 goto pre_stats; 640 #endif 641 /* 642 * Discard packet if upper layers shouldn't see it because it 643 * was unicast to a different Ethernet address. If the driver 644 * is working properly, then this situation can only happen 645 * when the interface is in promiscuous mode. 646 * 647 * If VLANs are active, and this packet has a VLAN tag, do 648 * not drop it here but pass it on to the VLAN layer, to 649 * give them a chance to consider it as well (e. g. in case 650 * bridging is only active on a VLAN). They will drop it if 651 * it's undesired. 652 */ 653 if ((ifp->if_flags & IFF_PROMISC) != 0 654 && !ETHER_IS_MULTICAST(eh->ether_dhost) 655 && bcmp(eh->ether_dhost, 656 IF_LLADDR(ifp), ETHER_ADDR_LEN) != 0 657 && (ifp->if_flags & IFF_PPROMISC) == 0) { 658 m_freem(m); 659 return; 660 } 661 } 662 663 #ifdef DEV_CARP 664 pre_stats: 665 #endif 666 /* Discard packet if interface is not up */ 667 if ((ifp->if_flags & IFF_UP) == 0) { 668 m_freem(m); 669 return; 670 } 671 if (ETHER_IS_MULTICAST(eh->ether_dhost)) { 672 if (bcmp(etherbroadcastaddr, eh->ether_dhost, 673 sizeof(etherbroadcastaddr)) == 0) 674 m->m_flags |= M_BCAST; 675 else 676 m->m_flags |= M_MCAST; 677 } 678 if (m->m_flags & (M_BCAST|M_MCAST)) 679 ifp->if_imcasts++; 680 681 #if defined(INET) || defined(INET6) 682 post_stats: 683 if (IPFW_LOADED && ether_ipfw != 0) { 684 if (ether_ipfw_chk(&m, NULL, &rule, 0) == 0) { 685 if (m) 686 m_freem(m); 687 return; 688 } 689 } 690 #endif 691 692 /* 693 * Check to see if the device performed the VLAN decapsulation and 694 * provided us with the tag. 695 */ 696 if (m->m_flags & M_VLANTAG) { 697 /* 698 * If no VLANs are configured, drop. 699 */ 700 if (ifp->if_vlantrunk == NULL) { 701 ifp->if_noproto++; 702 m_freem(m); 703 return; 704 } 705 /* 706 * vlan_input() will either recursively call ether_input() 707 * or drop the packet. 708 */ 709 KASSERT(vlan_input_p != NULL,("ether_input: VLAN not loaded!")); 710 (*vlan_input_p)(ifp, m); 711 return; 712 } 713 714 /* 715 * Handle protocols that expect to have the Ethernet header 716 * (and possibly FCS) intact. 717 */ 718 switch (ether_type) { 719 case ETHERTYPE_VLAN: 720 if (ifp->if_vlantrunk != NULL) { 721 KASSERT(vlan_input_p,("ether_input: VLAN not loaded!")); 722 (*vlan_input_p)(ifp, m); 723 } else { 724 ifp->if_noproto++; 725 m_freem(m); 726 } 727 return; 728 } 729 730 /* Strip off Ethernet header. */ 731 m_adj(m, ETHER_HDR_LEN); 732 733 /* If the CRC is still on the packet, trim it off. */ 734 if (m->m_flags & M_HASFCS) { 735 m_adj(m, -ETHER_CRC_LEN); 736 m->m_flags &= ~M_HASFCS; 737 } 738 739 /* Reset layer specific mbuf flags to avoid confusing upper layers. */ 740 m->m_flags &= ~(M_PROTOFLAGS); 741 742 switch (ether_type) { 743 #ifdef INET 744 case ETHERTYPE_IP: 745 if ((m = ip_fastforward(m)) == NULL) 746 return; 747 isr = NETISR_IP; 748 break; 749 750 case ETHERTYPE_ARP: 751 if (ifp->if_flags & IFF_NOARP) { 752 /* Discard packet if ARP is disabled on interface */ 753 m_freem(m); 754 return; 755 } 756 isr = NETISR_ARP; 757 break; 758 #endif 759 #ifdef IPX 760 case ETHERTYPE_IPX: 761 if (ef_inputp && ef_inputp(ifp, eh, m) == 0) 762 return; 763 isr = NETISR_IPX; 764 break; 765 #endif 766 #ifdef INET6 767 case ETHERTYPE_IPV6: 768 isr = NETISR_IPV6; 769 break; 770 #endif 771 #ifdef NETATALK 772 case ETHERTYPE_AT: 773 isr = NETISR_ATALK1; 774 break; 775 case ETHERTYPE_AARP: 776 isr = NETISR_AARP; 777 break; 778 #endif /* NETATALK */ 779 default: 780 #ifdef IPX 781 if (ef_inputp && ef_inputp(ifp, eh, m) == 0) 782 return; 783 #endif /* IPX */ 784 #if defined(NETATALK) 785 if (ether_type > ETHERMTU) 786 goto discard; 787 l = mtod(m, struct llc *); 788 if (l->llc_dsap == LLC_SNAP_LSAP && 789 l->llc_ssap == LLC_SNAP_LSAP && 790 l->llc_control == LLC_UI) { 791 if (bcmp(&(l->llc_snap_org_code)[0], at_org_code, 792 sizeof(at_org_code)) == 0 && 793 ntohs(l->llc_snap_ether_type) == ETHERTYPE_AT) { 794 m_adj(m, LLC_SNAPFRAMELEN); 795 isr = NETISR_ATALK2; 796 break; 797 } 798 if (bcmp(&(l->llc_snap_org_code)[0], aarp_org_code, 799 sizeof(aarp_org_code)) == 0 && 800 ntohs(l->llc_snap_ether_type) == ETHERTYPE_AARP) { 801 m_adj(m, LLC_SNAPFRAMELEN); 802 isr = NETISR_AARP; 803 break; 804 } 805 } 806 #endif /* NETATALK */ 807 goto discard; 808 } 809 netisr_dispatch(isr, m); 810 return; 811 812 discard: 813 /* 814 * Packet is to be discarded. If netgraph is present, 815 * hand the packet to it for last chance processing; 816 * otherwise dispose of it. 817 */ 818 if (IFP2AC(ifp)->ac_netgraph != NULL) { 819 KASSERT(ng_ether_input_orphan_p != NULL, 820 ("ng_ether_input_orphan_p is NULL")); 821 /* 822 * Put back the ethernet header so netgraph has a 823 * consistent view of inbound packets. 824 */ 825 M_PREPEND(m, ETHER_HDR_LEN, M_DONTWAIT); 826 (*ng_ether_input_orphan_p)(ifp, m); 827 return; 828 } 829 m_freem(m); 830 } 831 832 /* 833 * Convert Ethernet address to printable (loggable) representation. 834 * This routine is for compatibility; it's better to just use 835 * 836 * printf("%6D", <pointer to address>, ":"); 837 * 838 * since there's no static buffer involved. 839 */ 840 char * 841 ether_sprintf(const u_char *ap) 842 { 843 static char etherbuf[18]; 844 snprintf(etherbuf, sizeof (etherbuf), "%6D", ap, ":"); 845 return (etherbuf); 846 } 847 848 /* 849 * Perform common duties while attaching to interface list 850 */ 851 void 852 ether_ifattach(struct ifnet *ifp, const u_int8_t *lla) 853 { 854 int i; 855 struct ifaddr *ifa; 856 struct sockaddr_dl *sdl; 857 858 ifp->if_addrlen = ETHER_ADDR_LEN; 859 ifp->if_hdrlen = ETHER_HDR_LEN; 860 if_attach(ifp); 861 ifp->if_mtu = ETHERMTU; 862 ifp->if_output = ether_output; 863 ifp->if_input = ether_input; 864 ifp->if_resolvemulti = ether_resolvemulti; 865 if (ifp->if_baudrate == 0) 866 ifp->if_baudrate = IF_Mbps(10); /* just a default */ 867 ifp->if_broadcastaddr = etherbroadcastaddr; 868 869 ifa = ifp->if_addr; 870 KASSERT(ifa != NULL, ("%s: no lladdr!\n", __func__)); 871 sdl = (struct sockaddr_dl *)ifa->ifa_addr; 872 sdl->sdl_type = IFT_ETHER; 873 sdl->sdl_alen = ifp->if_addrlen; 874 bcopy(lla, LLADDR(sdl), ifp->if_addrlen); 875 876 bpfattach(ifp, DLT_EN10MB, ETHER_HDR_LEN); 877 if (ng_ether_attach_p != NULL) 878 (*ng_ether_attach_p)(ifp); 879 880 /* Announce Ethernet MAC address if non-zero. */ 881 for (i = 0; i < ifp->if_addrlen; i++) 882 if (lla[i] != 0) 883 break; 884 if (i != ifp->if_addrlen) 885 if_printf(ifp, "Ethernet address: %6D\n", lla, ":"); 886 if (debug_mpsafenet && (ifp->if_flags & IFF_NEEDSGIANT) != 0) 887 if_printf(ifp, "if_start running deferred for Giant\n"); 888 } 889 890 /* 891 * Perform common duties while detaching an Ethernet interface 892 */ 893 void 894 ether_ifdetach(struct ifnet *ifp) 895 { 896 if (IFP2AC(ifp)->ac_netgraph != NULL) { 897 KASSERT(ng_ether_detach_p != NULL, 898 ("ng_ether_detach_p is NULL")); 899 (*ng_ether_detach_p)(ifp); 900 } 901 902 bpfdetach(ifp); 903 if_detach(ifp); 904 } 905 906 SYSCTL_DECL(_net_link); 907 SYSCTL_NODE(_net_link, IFT_ETHER, ether, CTLFLAG_RW, 0, "Ethernet"); 908 #if defined(INET) || defined(INET6) 909 SYSCTL_INT(_net_link_ether, OID_AUTO, ipfw, CTLFLAG_RW, 910 ðer_ipfw,0,"Pass ether pkts through firewall"); 911 #endif 912 913 #if 0 914 /* 915 * This is for reference. We have a table-driven version 916 * of the little-endian crc32 generator, which is faster 917 * than the double-loop. 918 */ 919 uint32_t 920 ether_crc32_le(const uint8_t *buf, size_t len) 921 { 922 size_t i; 923 uint32_t crc; 924 int bit; 925 uint8_t data; 926 927 crc = 0xffffffff; /* initial value */ 928 929 for (i = 0; i < len; i++) { 930 for (data = *buf++, bit = 0; bit < 8; bit++, data >>= 1) 931 carry = (crc ^ data) & 1; 932 crc >>= 1; 933 if (carry) 934 crc = (crc ^ ETHER_CRC_POLY_LE); 935 } 936 937 return (crc); 938 } 939 #else 940 uint32_t 941 ether_crc32_le(const uint8_t *buf, size_t len) 942 { 943 static const uint32_t crctab[] = { 944 0x00000000, 0x1db71064, 0x3b6e20c8, 0x26d930ac, 945 0x76dc4190, 0x6b6b51f4, 0x4db26158, 0x5005713c, 946 0xedb88320, 0xf00f9344, 0xd6d6a3e8, 0xcb61b38c, 947 0x9b64c2b0, 0x86d3d2d4, 0xa00ae278, 0xbdbdf21c 948 }; 949 size_t i; 950 uint32_t crc; 951 952 crc = 0xffffffff; /* initial value */ 953 954 for (i = 0; i < len; i++) { 955 crc ^= buf[i]; 956 crc = (crc >> 4) ^ crctab[crc & 0xf]; 957 crc = (crc >> 4) ^ crctab[crc & 0xf]; 958 } 959 960 return (crc); 961 } 962 #endif 963 964 uint32_t 965 ether_crc32_be(const uint8_t *buf, size_t len) 966 { 967 size_t i; 968 uint32_t crc, carry; 969 int bit; 970 uint8_t data; 971 972 crc = 0xffffffff; /* initial value */ 973 974 for (i = 0; i < len; i++) { 975 for (data = *buf++, bit = 0; bit < 8; bit++, data >>= 1) { 976 carry = ((crc & 0x80000000) ? 1 : 0) ^ (data & 0x01); 977 crc <<= 1; 978 if (carry) 979 crc = (crc ^ ETHER_CRC_POLY_BE) | carry; 980 } 981 } 982 983 return (crc); 984 } 985 986 int 987 ether_ioctl(struct ifnet *ifp, int command, caddr_t data) 988 { 989 struct ifaddr *ifa = (struct ifaddr *) data; 990 struct ifreq *ifr = (struct ifreq *) data; 991 int error = 0; 992 993 switch (command) { 994 case SIOCSIFADDR: 995 ifp->if_flags |= IFF_UP; 996 997 switch (ifa->ifa_addr->sa_family) { 998 #ifdef INET 999 case AF_INET: 1000 ifp->if_init(ifp->if_softc); /* before arpwhohas */ 1001 arp_ifinit(ifp, ifa); 1002 break; 1003 #endif 1004 #ifdef IPX 1005 /* 1006 * XXX - This code is probably wrong 1007 */ 1008 case AF_IPX: 1009 { 1010 struct ipx_addr *ina = &(IA_SIPX(ifa)->sipx_addr); 1011 1012 if (ipx_nullhost(*ina)) 1013 ina->x_host = 1014 *(union ipx_host *) 1015 IF_LLADDR(ifp); 1016 else { 1017 bcopy((caddr_t) ina->x_host.c_host, 1018 (caddr_t) IF_LLADDR(ifp), 1019 ETHER_ADDR_LEN); 1020 } 1021 1022 /* 1023 * Set new address 1024 */ 1025 ifp->if_init(ifp->if_softc); 1026 break; 1027 } 1028 #endif 1029 default: 1030 ifp->if_init(ifp->if_softc); 1031 break; 1032 } 1033 break; 1034 1035 case SIOCGIFADDR: 1036 { 1037 struct sockaddr *sa; 1038 1039 sa = (struct sockaddr *) & ifr->ifr_data; 1040 bcopy(IF_LLADDR(ifp), 1041 (caddr_t) sa->sa_data, ETHER_ADDR_LEN); 1042 } 1043 break; 1044 1045 case SIOCSIFMTU: 1046 /* 1047 * Set the interface MTU. 1048 */ 1049 if (ifr->ifr_mtu > ETHERMTU) { 1050 error = EINVAL; 1051 } else { 1052 ifp->if_mtu = ifr->ifr_mtu; 1053 } 1054 break; 1055 default: 1056 error = EINVAL; /* XXX netbsd has ENOTTY??? */ 1057 break; 1058 } 1059 return (error); 1060 } 1061 1062 static int 1063 ether_resolvemulti(struct ifnet *ifp, struct sockaddr **llsa, 1064 struct sockaddr *sa) 1065 { 1066 struct sockaddr_dl *sdl; 1067 #ifdef INET 1068 struct sockaddr_in *sin; 1069 #endif 1070 #ifdef INET6 1071 struct sockaddr_in6 *sin6; 1072 #endif 1073 u_char *e_addr; 1074 1075 switch(sa->sa_family) { 1076 case AF_LINK: 1077 /* 1078 * No mapping needed. Just check that it's a valid MC address. 1079 */ 1080 sdl = (struct sockaddr_dl *)sa; 1081 e_addr = LLADDR(sdl); 1082 if (!ETHER_IS_MULTICAST(e_addr)) 1083 return EADDRNOTAVAIL; 1084 *llsa = 0; 1085 return 0; 1086 1087 #ifdef INET 1088 case AF_INET: 1089 sin = (struct sockaddr_in *)sa; 1090 if (!IN_MULTICAST(ntohl(sin->sin_addr.s_addr))) 1091 return EADDRNOTAVAIL; 1092 MALLOC(sdl, struct sockaddr_dl *, sizeof *sdl, M_IFMADDR, 1093 M_NOWAIT|M_ZERO); 1094 if (sdl == NULL) 1095 return ENOMEM; 1096 sdl->sdl_len = sizeof *sdl; 1097 sdl->sdl_family = AF_LINK; 1098 sdl->sdl_index = ifp->if_index; 1099 sdl->sdl_type = IFT_ETHER; 1100 sdl->sdl_alen = ETHER_ADDR_LEN; 1101 e_addr = LLADDR(sdl); 1102 ETHER_MAP_IP_MULTICAST(&sin->sin_addr, e_addr); 1103 *llsa = (struct sockaddr *)sdl; 1104 return 0; 1105 #endif 1106 #ifdef INET6 1107 case AF_INET6: 1108 sin6 = (struct sockaddr_in6 *)sa; 1109 if (IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr)) { 1110 /* 1111 * An IP6 address of 0 means listen to all 1112 * of the Ethernet multicast address used for IP6. 1113 * (This is used for multicast routers.) 1114 */ 1115 ifp->if_flags |= IFF_ALLMULTI; 1116 *llsa = 0; 1117 return 0; 1118 } 1119 if (!IN6_IS_ADDR_MULTICAST(&sin6->sin6_addr)) 1120 return EADDRNOTAVAIL; 1121 MALLOC(sdl, struct sockaddr_dl *, sizeof *sdl, M_IFMADDR, 1122 M_NOWAIT|M_ZERO); 1123 if (sdl == NULL) 1124 return (ENOMEM); 1125 sdl->sdl_len = sizeof *sdl; 1126 sdl->sdl_family = AF_LINK; 1127 sdl->sdl_index = ifp->if_index; 1128 sdl->sdl_type = IFT_ETHER; 1129 sdl->sdl_alen = ETHER_ADDR_LEN; 1130 e_addr = LLADDR(sdl); 1131 ETHER_MAP_IPV6_MULTICAST(&sin6->sin6_addr, e_addr); 1132 *llsa = (struct sockaddr *)sdl; 1133 return 0; 1134 #endif 1135 1136 default: 1137 /* 1138 * Well, the text isn't quite right, but it's the name 1139 * that counts... 1140 */ 1141 return EAFNOSUPPORT; 1142 } 1143 } 1144 1145 static void* 1146 ether_alloc(u_char type, struct ifnet *ifp) 1147 { 1148 struct arpcom *ac; 1149 1150 ac = malloc(sizeof(struct arpcom), M_ARPCOM, M_WAITOK | M_ZERO); 1151 ac->ac_ifp = ifp; 1152 1153 return (ac); 1154 } 1155 1156 static void 1157 ether_free(void *com, u_char type) 1158 { 1159 1160 free(com, M_ARPCOM); 1161 } 1162 1163 static int 1164 ether_modevent(module_t mod, int type, void *data) 1165 { 1166 1167 switch (type) { 1168 case MOD_LOAD: 1169 if_register_com_alloc(IFT_ETHER, ether_alloc, ether_free); 1170 break; 1171 case MOD_UNLOAD: 1172 if_deregister_com_alloc(IFT_ETHER); 1173 break; 1174 default: 1175 return EOPNOTSUPP; 1176 } 1177 1178 return (0); 1179 } 1180 1181 static moduledata_t ether_mod = { 1182 "ether", 1183 ether_modevent, 1184 0 1185 }; 1186 1187 DECLARE_MODULE(ether, ether_mod, SI_SUB_INIT_IF, SI_ORDER_ANY); 1188 MODULE_VERSION(ether, 1); 1189