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_route.h" 38 #include "opt_mac.h" 39 #include "opt_netgraph.h" 40 #include "opt_carp.h" 41 #include "opt_mbuf_profiling.h" 42 43 #include <sys/param.h> 44 #include <sys/systm.h> 45 #include <sys/kernel.h> 46 #include <sys/lock.h> 47 #include <sys/malloc.h> 48 #include <sys/module.h> 49 #include <sys/mbuf.h> 50 #include <sys/random.h> 51 #include <sys/rwlock.h> 52 #include <sys/socket.h> 53 #include <sys/sockio.h> 54 #include <sys/sysctl.h> 55 #include <sys/vimage.h> 56 57 #include <net/if.h> 58 #include <net/if_arp.h> 59 #include <net/netisr.h> 60 #include <net/route.h> 61 #include <net/if_llc.h> 62 #include <net/if_dl.h> 63 #include <net/if_types.h> 64 #include <net/bpf.h> 65 #include <net/ethernet.h> 66 #include <net/if_bridgevar.h> 67 #include <net/if_vlan_var.h> 68 #include <net/if_llatbl.h> 69 #include <net/pf_mtag.h> 70 #include <net/vnet.h> 71 72 #if defined(INET) || defined(INET6) 73 #include <netinet/in.h> 74 #include <netinet/in_var.h> 75 #include <netinet/if_ether.h> 76 #include <netinet/ip_fw.h> 77 #include <netinet/ip_dummynet.h> 78 #include <netinet/vinet.h> 79 #endif 80 #ifdef INET6 81 #include <netinet6/nd6.h> 82 #endif 83 84 #ifdef DEV_CARP 85 #include <netinet/ip_carp.h> 86 #endif 87 88 #ifdef IPX 89 #include <netipx/ipx.h> 90 #include <netipx/ipx_if.h> 91 #endif 92 93 int (*ef_inputp)(struct ifnet*, struct ether_header *eh, struct mbuf *m); 94 int (*ef_outputp)(struct ifnet *ifp, struct mbuf **mp, 95 struct sockaddr *dst, short *tp, int *hlen); 96 97 #ifdef NETATALK 98 #include <netatalk/at.h> 99 #include <netatalk/at_var.h> 100 #include <netatalk/at_extern.h> 101 102 #define llc_snap_org_code llc_un.type_snap.org_code 103 #define llc_snap_ether_type llc_un.type_snap.ether_type 104 105 extern u_char at_org_code[3]; 106 extern u_char aarp_org_code[3]; 107 #endif /* NETATALK */ 108 109 #include <security/mac/mac_framework.h> 110 111 #ifdef CTASSERT 112 CTASSERT(sizeof (struct ether_header) == ETHER_ADDR_LEN * 2 + 2); 113 CTASSERT(sizeof (struct ether_addr) == ETHER_ADDR_LEN); 114 #endif 115 116 /* netgraph node hooks for ng_ether(4) */ 117 void (*ng_ether_input_p)(struct ifnet *ifp, struct mbuf **mp); 118 void (*ng_ether_input_orphan_p)(struct ifnet *ifp, struct mbuf *m); 119 int (*ng_ether_output_p)(struct ifnet *ifp, struct mbuf **mp); 120 void (*ng_ether_attach_p)(struct ifnet *ifp); 121 void (*ng_ether_detach_p)(struct ifnet *ifp); 122 123 void (*vlan_input_p)(struct ifnet *, struct mbuf *); 124 125 /* if_bridge(4) support */ 126 struct mbuf *(*bridge_input_p)(struct ifnet *, struct mbuf *); 127 int (*bridge_output_p)(struct ifnet *, struct mbuf *, 128 struct sockaddr *, struct rtentry *); 129 void (*bridge_dn_p)(struct mbuf *, struct ifnet *); 130 131 /* if_lagg(4) support */ 132 struct mbuf *(*lagg_input_p)(struct ifnet *, struct mbuf *); 133 134 static const u_char etherbroadcastaddr[ETHER_ADDR_LEN] = 135 { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff }; 136 137 static int ether_resolvemulti(struct ifnet *, struct sockaddr **, 138 struct sockaddr *); 139 140 /* XXX: should be in an arp support file, not here */ 141 MALLOC_DEFINE(M_ARPCOM, "arpcom", "802.* interface internals"); 142 143 #define ETHER_IS_BROADCAST(addr) \ 144 (bcmp(etherbroadcastaddr, (addr), ETHER_ADDR_LEN) == 0) 145 146 #define senderr(e) do { error = (e); goto bad;} while (0) 147 148 #if defined(INET) || defined(INET6) 149 int 150 ether_ipfw_chk(struct mbuf **m0, struct ifnet *dst, 151 struct ip_fw **rule, int shared); 152 #ifdef VIMAGE_GLOBALS 153 static int ether_ipfw; 154 #endif 155 #endif 156 157 158 /* 159 * Ethernet output routine. 160 * Encapsulate a packet of type family for the local net. 161 * Use trailer local net encapsulation if enough data in first 162 * packet leaves a multiple of 512 bytes of data in remainder. 163 */ 164 int 165 ether_output(struct ifnet *ifp, struct mbuf *m, 166 struct sockaddr *dst, struct route *ro) 167 { 168 short type; 169 int error = 0, hdrcmplt = 0; 170 u_char esrc[ETHER_ADDR_LEN], edst[ETHER_ADDR_LEN]; 171 struct llentry *lle = NULL; 172 struct rtentry *rt0 = NULL; 173 struct ether_header *eh; 174 struct pf_mtag *t; 175 int loop_copy = 1; 176 int hlen; /* link layer header length */ 177 178 if (ro != NULL) { 179 lle = ro->ro_lle; 180 rt0 = ro->ro_rt; 181 } 182 #ifdef MAC 183 error = mac_ifnet_check_transmit(ifp, m); 184 if (error) 185 senderr(error); 186 #endif 187 188 M_PROFILE(m); 189 if (ifp->if_flags & IFF_MONITOR) 190 senderr(ENETDOWN); 191 if (!((ifp->if_flags & IFF_UP) && 192 (ifp->if_drv_flags & IFF_DRV_RUNNING))) 193 senderr(ENETDOWN); 194 195 hlen = ETHER_HDR_LEN; 196 switch (dst->sa_family) { 197 #ifdef INET 198 case AF_INET: 199 if (lle != NULL && (lle->la_flags & LLE_VALID)) 200 memcpy(edst, &lle->ll_addr.mac16, sizeof(edst)); 201 else 202 error = arpresolve(ifp, rt0, m, dst, edst, &lle); 203 if (error) 204 return (error == EWOULDBLOCK ? 0 : error); 205 type = htons(ETHERTYPE_IP); 206 break; 207 case AF_ARP: 208 { 209 struct arphdr *ah; 210 ah = mtod(m, struct arphdr *); 211 ah->ar_hrd = htons(ARPHRD_ETHER); 212 213 loop_copy = 0; /* if this is for us, don't do it */ 214 215 switch(ntohs(ah->ar_op)) { 216 case ARPOP_REVREQUEST: 217 case ARPOP_REVREPLY: 218 type = htons(ETHERTYPE_REVARP); 219 break; 220 case ARPOP_REQUEST: 221 case ARPOP_REPLY: 222 default: 223 type = htons(ETHERTYPE_ARP); 224 break; 225 } 226 227 if (m->m_flags & M_BCAST) 228 bcopy(ifp->if_broadcastaddr, edst, ETHER_ADDR_LEN); 229 else 230 bcopy(ar_tha(ah), edst, ETHER_ADDR_LEN); 231 232 } 233 break; 234 #endif 235 #ifdef INET6 236 case AF_INET6: 237 if (lle != NULL && (lle->la_flags & LLE_VALID)) 238 memcpy(edst, &lle->ll_addr.mac16, sizeof(edst)); 239 else 240 error = nd6_storelladdr(ifp, m, dst, (u_char *)edst, &lle); 241 if (error) 242 return error; 243 type = htons(ETHERTYPE_IPV6); 244 break; 245 #endif 246 #ifdef IPX 247 case AF_IPX: 248 if (ef_outputp) { 249 error = ef_outputp(ifp, &m, dst, &type, &hlen); 250 if (error) 251 goto bad; 252 } else 253 type = htons(ETHERTYPE_IPX); 254 bcopy((caddr_t)&(((struct sockaddr_ipx *)dst)->sipx_addr.x_host), 255 (caddr_t)edst, sizeof (edst)); 256 break; 257 #endif 258 #ifdef NETATALK 259 case AF_APPLETALK: 260 { 261 struct at_ifaddr *aa; 262 263 if ((aa = at_ifawithnet((struct sockaddr_at *)dst)) == NULL) 264 senderr(EHOSTUNREACH); /* XXX */ 265 if (!aarpresolve(ifp, m, (struct sockaddr_at *)dst, edst)) 266 return (0); 267 /* 268 * In the phase 2 case, need to prepend an mbuf for the llc header. 269 */ 270 if ( aa->aa_flags & AFA_PHASE2 ) { 271 struct llc llc; 272 273 M_PREPEND(m, LLC_SNAPFRAMELEN, M_DONTWAIT); 274 if (m == NULL) 275 senderr(ENOBUFS); 276 llc.llc_dsap = llc.llc_ssap = LLC_SNAP_LSAP; 277 llc.llc_control = LLC_UI; 278 bcopy(at_org_code, llc.llc_snap_org_code, sizeof(at_org_code)); 279 llc.llc_snap_ether_type = htons( ETHERTYPE_AT ); 280 bcopy(&llc, mtod(m, caddr_t), LLC_SNAPFRAMELEN); 281 type = htons(m->m_pkthdr.len); 282 hlen = LLC_SNAPFRAMELEN + ETHER_HDR_LEN; 283 } else { 284 type = htons(ETHERTYPE_AT); 285 } 286 break; 287 } 288 #endif /* NETATALK */ 289 290 case pseudo_AF_HDRCMPLT: 291 hdrcmplt = 1; 292 eh = (struct ether_header *)dst->sa_data; 293 (void)memcpy(esrc, eh->ether_shost, sizeof (esrc)); 294 /* FALLTHROUGH */ 295 296 case AF_UNSPEC: 297 loop_copy = 0; /* if this is for us, don't do it */ 298 eh = (struct ether_header *)dst->sa_data; 299 (void)memcpy(edst, eh->ether_dhost, sizeof (edst)); 300 type = eh->ether_type; 301 break; 302 303 default: 304 if_printf(ifp, "can't handle af%d\n", dst->sa_family); 305 senderr(EAFNOSUPPORT); 306 } 307 308 if (lle != NULL && (lle->la_flags & LLE_IFADDR)) { 309 int csum_flags = 0; 310 if (m->m_pkthdr.csum_flags & CSUM_IP) 311 csum_flags |= (CSUM_IP_CHECKED|CSUM_IP_VALID); 312 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) 313 csum_flags |= (CSUM_DATA_VALID|CSUM_PSEUDO_HDR); 314 if (m->m_pkthdr.csum_flags & CSUM_SCTP) 315 csum_flags |= CSUM_SCTP_VALID; 316 m->m_pkthdr.csum_flags |= csum_flags; 317 m->m_pkthdr.csum_data = 0xffff; 318 return (if_simloop(ifp, m, dst->sa_family, 0)); 319 } 320 321 /* 322 * Add local net header. If no space in first mbuf, 323 * allocate another. 324 */ 325 M_PREPEND(m, ETHER_HDR_LEN, M_DONTWAIT); 326 if (m == NULL) 327 senderr(ENOBUFS); 328 eh = mtod(m, struct ether_header *); 329 (void)memcpy(&eh->ether_type, &type, 330 sizeof(eh->ether_type)); 331 (void)memcpy(eh->ether_dhost, edst, sizeof (edst)); 332 if (hdrcmplt) 333 (void)memcpy(eh->ether_shost, esrc, 334 sizeof(eh->ether_shost)); 335 else 336 (void)memcpy(eh->ether_shost, IF_LLADDR(ifp), 337 sizeof(eh->ether_shost)); 338 339 /* 340 * If a simplex interface, and the packet is being sent to our 341 * Ethernet address or a broadcast address, loopback a copy. 342 * XXX To make a simplex device behave exactly like a duplex 343 * device, we should copy in the case of sending to our own 344 * ethernet address (thus letting the original actually appear 345 * on the wire). However, we don't do that here for security 346 * reasons and compatibility with the original behavior. 347 */ 348 if ((ifp->if_flags & IFF_SIMPLEX) && loop_copy && 349 ((t = pf_find_mtag(m)) == NULL || !t->routed)) { 350 int csum_flags = 0; 351 352 if (m->m_pkthdr.csum_flags & CSUM_IP) 353 csum_flags |= (CSUM_IP_CHECKED|CSUM_IP_VALID); 354 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) 355 csum_flags |= (CSUM_DATA_VALID|CSUM_PSEUDO_HDR); 356 if (m->m_pkthdr.csum_flags & CSUM_SCTP) 357 csum_flags |= CSUM_SCTP_VALID; 358 359 if (m->m_flags & M_BCAST) { 360 struct mbuf *n; 361 362 /* 363 * Because if_simloop() modifies the packet, we need a 364 * writable copy through m_dup() instead of a readonly 365 * one as m_copy[m] would give us. The alternative would 366 * be to modify if_simloop() to handle the readonly mbuf, 367 * but performancewise it is mostly equivalent (trading 368 * extra data copying vs. extra locking). 369 * 370 * XXX This is a local workaround. A number of less 371 * often used kernel parts suffer from the same bug. 372 * See PR kern/105943 for a proposed general solution. 373 */ 374 if ((n = m_dup(m, M_DONTWAIT)) != NULL) { 375 n->m_pkthdr.csum_flags |= csum_flags; 376 if (csum_flags & CSUM_DATA_VALID) 377 n->m_pkthdr.csum_data = 0xffff; 378 (void)if_simloop(ifp, n, dst->sa_family, hlen); 379 } else 380 ifp->if_iqdrops++; 381 } else if (bcmp(eh->ether_dhost, eh->ether_shost, 382 ETHER_ADDR_LEN) == 0) { 383 m->m_pkthdr.csum_flags |= csum_flags; 384 if (csum_flags & CSUM_DATA_VALID) 385 m->m_pkthdr.csum_data = 0xffff; 386 (void) if_simloop(ifp, m, dst->sa_family, hlen); 387 return (0); /* XXX */ 388 } 389 } 390 391 /* 392 * Bridges require special output handling. 393 */ 394 if (ifp->if_bridge) { 395 BRIDGE_OUTPUT(ifp, m, error); 396 return (error); 397 } 398 399 #ifdef DEV_CARP 400 if (ifp->if_carp && 401 (error = carp_output(ifp, m, dst, NULL))) 402 goto bad; 403 #endif 404 405 /* Handle ng_ether(4) processing, if any */ 406 if (IFP2AC(ifp)->ac_netgraph != NULL) { 407 KASSERT(ng_ether_output_p != NULL, 408 ("ng_ether_output_p is NULL")); 409 if ((error = (*ng_ether_output_p)(ifp, &m)) != 0) { 410 bad: if (m != NULL) 411 m_freem(m); 412 return (error); 413 } 414 if (m == NULL) 415 return (0); 416 } 417 418 /* Continue with link-layer output */ 419 return ether_output_frame(ifp, m); 420 } 421 422 /* 423 * Ethernet link layer output routine to send a raw frame to the device. 424 * 425 * This assumes that the 14 byte Ethernet header is present and contiguous 426 * in the first mbuf (if BRIDGE'ing). 427 */ 428 int 429 ether_output_frame(struct ifnet *ifp, struct mbuf *m) 430 { 431 #if defined(INET) || defined(INET6) 432 INIT_VNET_NET(ifp->if_vnet); 433 struct ip_fw *rule = ip_dn_claim_rule(m); 434 435 if (IPFW_LOADED && V_ether_ipfw != 0) { 436 if (ether_ipfw_chk(&m, ifp, &rule, 0) == 0) { 437 if (m) { 438 m_freem(m); 439 return EACCES; /* pkt dropped */ 440 } else 441 return 0; /* consumed e.g. in a pipe */ 442 } 443 } 444 #endif 445 446 /* 447 * Queue message on interface, update output statistics if 448 * successful, and start output if interface not yet active. 449 */ 450 return ((ifp->if_transmit)(ifp, m)); 451 } 452 453 #if defined(INET) || defined(INET6) 454 /* 455 * ipfw processing for ethernet packets (in and out). 456 * The second parameter is NULL from ether_demux, and ifp from 457 * ether_output_frame. 458 */ 459 int 460 ether_ipfw_chk(struct mbuf **m0, struct ifnet *dst, 461 struct ip_fw **rule, int shared) 462 { 463 INIT_VNET_INET(dst->if_vnet); 464 struct ether_header *eh; 465 struct ether_header save_eh; 466 struct mbuf *m; 467 int i; 468 struct ip_fw_args args; 469 470 if (*rule != NULL && V_fw_one_pass) 471 return 1; /* dummynet packet, already partially processed */ 472 473 /* 474 * I need some amt of data to be contiguous, and in case others need 475 * the packet (shared==1) also better be in the first mbuf. 476 */ 477 m = *m0; 478 i = min( m->m_pkthdr.len, max_protohdr); 479 if ( shared || m->m_len < i) { 480 m = m_pullup(m, i); 481 if (m == NULL) { 482 *m0 = m; 483 return 0; 484 } 485 } 486 eh = mtod(m, struct ether_header *); 487 save_eh = *eh; /* save copy for restore below */ 488 m_adj(m, ETHER_HDR_LEN); /* strip ethernet header */ 489 490 args.m = m; /* the packet we are looking at */ 491 args.oif = dst; /* destination, if any */ 492 args.rule = *rule; /* matching rule to restart */ 493 args.next_hop = NULL; /* we do not support forward yet */ 494 args.eh = &save_eh; /* MAC header for bridged/MAC packets */ 495 args.inp = NULL; /* used by ipfw uid/gid/jail rules */ 496 i = ip_fw_chk_ptr(&args); 497 m = args.m; 498 if (m != NULL) { 499 /* 500 * Restore Ethernet header, as needed, in case the 501 * mbuf chain was replaced by ipfw. 502 */ 503 M_PREPEND(m, ETHER_HDR_LEN, M_DONTWAIT); 504 if (m == NULL) { 505 *m0 = m; 506 return 0; 507 } 508 if (eh != mtod(m, struct ether_header *)) 509 bcopy(&save_eh, mtod(m, struct ether_header *), 510 ETHER_HDR_LEN); 511 } 512 *m0 = m; 513 *rule = args.rule; 514 515 if (i == IP_FW_DENY) /* drop */ 516 return 0; 517 518 KASSERT(m != NULL, ("ether_ipfw_chk: m is NULL")); 519 520 if (i == IP_FW_PASS) /* a PASS rule. */ 521 return 1; 522 523 if (DUMMYNET_LOADED && (i == IP_FW_DUMMYNET)) { 524 /* 525 * Pass the pkt to dummynet, which consumes it. 526 * If shared, make a copy and keep the original. 527 */ 528 if (shared) { 529 m = m_copypacket(m, M_DONTWAIT); 530 if (m == NULL) 531 return 0; 532 } else { 533 /* 534 * Pass the original to dummynet and 535 * nothing back to the caller 536 */ 537 *m0 = NULL ; 538 } 539 ip_dn_io_ptr(&m, dst ? DN_TO_ETH_OUT: DN_TO_ETH_DEMUX, &args); 540 return 0; 541 } 542 /* 543 * XXX at some point add support for divert/forward actions. 544 * If none of the above matches, we have to drop the pkt. 545 */ 546 return 0; 547 } 548 #endif 549 550 /* 551 * Process a received Ethernet packet; the packet is in the 552 * mbuf chain m with the ethernet header at the front. 553 */ 554 static void 555 ether_input(struct ifnet *ifp, struct mbuf *m) 556 { 557 struct ether_header *eh; 558 u_short etype; 559 560 if ((ifp->if_flags & IFF_UP) == 0) { 561 m_freem(m); 562 return; 563 } 564 #ifdef DIAGNOSTIC 565 if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0) { 566 if_printf(ifp, "discard frame at !IFF_DRV_RUNNING\n"); 567 m_freem(m); 568 return; 569 } 570 #endif 571 /* 572 * Do consistency checks to verify assumptions 573 * made by code past this point. 574 */ 575 if ((m->m_flags & M_PKTHDR) == 0) { 576 if_printf(ifp, "discard frame w/o packet header\n"); 577 ifp->if_ierrors++; 578 m_freem(m); 579 return; 580 } 581 if (m->m_len < ETHER_HDR_LEN) { 582 /* XXX maybe should pullup? */ 583 if_printf(ifp, "discard frame w/o leading ethernet " 584 "header (len %u pkt len %u)\n", 585 m->m_len, m->m_pkthdr.len); 586 ifp->if_ierrors++; 587 m_freem(m); 588 return; 589 } 590 eh = mtod(m, struct ether_header *); 591 etype = ntohs(eh->ether_type); 592 if (m->m_pkthdr.rcvif == NULL) { 593 if_printf(ifp, "discard frame w/o interface pointer\n"); 594 ifp->if_ierrors++; 595 m_freem(m); 596 return; 597 } 598 #ifdef DIAGNOSTIC 599 if (m->m_pkthdr.rcvif != ifp) { 600 if_printf(ifp, "Warning, frame marked as received on %s\n", 601 m->m_pkthdr.rcvif->if_xname); 602 } 603 #endif 604 605 CURVNET_SET_QUIET(ifp->if_vnet); 606 607 if (ETHER_IS_MULTICAST(eh->ether_dhost)) { 608 if (ETHER_IS_BROADCAST(eh->ether_dhost)) 609 m->m_flags |= M_BCAST; 610 else 611 m->m_flags |= M_MCAST; 612 ifp->if_imcasts++; 613 } 614 615 #ifdef MAC 616 /* 617 * Tag the mbuf with an appropriate MAC label before any other 618 * consumers can get to it. 619 */ 620 mac_ifnet_create_mbuf(ifp, m); 621 #endif 622 623 /* 624 * Give bpf a chance at the packet. 625 */ 626 ETHER_BPF_MTAP(ifp, m); 627 628 /* 629 * If the CRC is still on the packet, trim it off. We do this once 630 * and once only in case we are re-entered. Nothing else on the 631 * Ethernet receive path expects to see the FCS. 632 */ 633 if (m->m_flags & M_HASFCS) { 634 m_adj(m, -ETHER_CRC_LEN); 635 m->m_flags &= ~M_HASFCS; 636 } 637 638 ifp->if_ibytes += m->m_pkthdr.len; 639 640 /* Allow monitor mode to claim this frame, after stats are updated. */ 641 if (ifp->if_flags & IFF_MONITOR) { 642 m_freem(m); 643 CURVNET_RESTORE(); 644 return; 645 } 646 647 /* Handle input from a lagg(4) port */ 648 if (ifp->if_type == IFT_IEEE8023ADLAG) { 649 KASSERT(lagg_input_p != NULL, 650 ("%s: if_lagg not loaded!", __func__)); 651 m = (*lagg_input_p)(ifp, m); 652 if (m != NULL) 653 ifp = m->m_pkthdr.rcvif; 654 else 655 return; 656 } 657 658 /* 659 * If the hardware did not process an 802.1Q tag, do this now, 660 * to allow 802.1P priority frames to be passed to the main input 661 * path correctly. 662 * TODO: Deal with Q-in-Q frames, but not arbitrary nesting levels. 663 */ 664 if ((m->m_flags & M_VLANTAG) == 0 && etype == ETHERTYPE_VLAN) { 665 struct ether_vlan_header *evl; 666 667 if (m->m_len < sizeof(*evl) && 668 (m = m_pullup(m, sizeof(*evl))) == NULL) { 669 #ifdef DIAGNOSTIC 670 if_printf(ifp, "cannot pullup VLAN header\n"); 671 #endif 672 ifp->if_ierrors++; 673 m_freem(m); 674 return; 675 } 676 677 evl = mtod(m, struct ether_vlan_header *); 678 m->m_pkthdr.ether_vtag = ntohs(evl->evl_tag); 679 m->m_flags |= M_VLANTAG; 680 681 bcopy((char *)evl, (char *)evl + ETHER_VLAN_ENCAP_LEN, 682 ETHER_HDR_LEN - ETHER_TYPE_LEN); 683 m_adj(m, ETHER_VLAN_ENCAP_LEN); 684 } 685 686 /* Allow ng_ether(4) to claim this frame. */ 687 if (IFP2AC(ifp)->ac_netgraph != NULL) { 688 KASSERT(ng_ether_input_p != NULL, 689 ("%s: ng_ether_input_p is NULL", __func__)); 690 m->m_flags &= ~M_PROMISC; 691 (*ng_ether_input_p)(ifp, &m); 692 if (m == NULL) { 693 CURVNET_RESTORE(); 694 return; 695 } 696 } 697 698 /* 699 * Allow if_bridge(4) to claim this frame. 700 * The BRIDGE_INPUT() macro will update ifp if the bridge changed it 701 * and the frame should be delivered locally. 702 */ 703 if (ifp->if_bridge != NULL) { 704 m->m_flags &= ~M_PROMISC; 705 BRIDGE_INPUT(ifp, m); 706 if (m == NULL) { 707 CURVNET_RESTORE(); 708 return; 709 } 710 } 711 712 #ifdef DEV_CARP 713 /* 714 * Clear M_PROMISC on frame so that carp(4) will see it when the 715 * mbuf flows up to Layer 3. 716 * FreeBSD's implementation of carp(4) uses the inprotosw 717 * to dispatch IPPROTO_CARP. carp(4) also allocates its own 718 * Ethernet addresses of the form 00:00:5e:00:01:xx, which 719 * is outside the scope of the M_PROMISC test below. 720 * TODO: Maintain a hash table of ethernet addresses other than 721 * ether_dhost which may be active on this ifp. 722 */ 723 if (ifp->if_carp && carp_forus(ifp->if_carp, eh->ether_dhost)) { 724 m->m_flags &= ~M_PROMISC; 725 } else 726 #endif 727 { 728 /* 729 * If the frame received was not for our MAC address, set the 730 * M_PROMISC flag on the mbuf chain. The frame may need to 731 * be seen by the rest of the Ethernet input path in case of 732 * re-entry (e.g. bridge, vlan, netgraph) but should not be 733 * seen by upper protocol layers. 734 */ 735 if (!ETHER_IS_MULTICAST(eh->ether_dhost) && 736 bcmp(IF_LLADDR(ifp), eh->ether_dhost, ETHER_ADDR_LEN) != 0) 737 m->m_flags |= M_PROMISC; 738 } 739 740 /* First chunk of an mbuf contains good entropy */ 741 if (harvest.ethernet) 742 random_harvest(m, 16, 3, 0, RANDOM_NET); 743 744 ether_demux(ifp, m); 745 CURVNET_RESTORE(); 746 } 747 748 /* 749 * Upper layer processing for a received Ethernet packet. 750 */ 751 void 752 ether_demux(struct ifnet *ifp, struct mbuf *m) 753 { 754 struct ether_header *eh; 755 int isr; 756 u_short ether_type; 757 #if defined(NETATALK) 758 struct llc *l; 759 #endif 760 761 KASSERT(ifp != NULL, ("%s: NULL interface pointer", __func__)); 762 763 #if defined(INET) || defined(INET6) 764 INIT_VNET_NET(ifp->if_vnet); 765 /* 766 * Allow dummynet and/or ipfw to claim the frame. 767 * Do not do this for PROMISC frames in case we are re-entered. 768 */ 769 if (IPFW_LOADED && V_ether_ipfw != 0 && !(m->m_flags & M_PROMISC)) { 770 struct ip_fw *rule = ip_dn_claim_rule(m); 771 772 if (ether_ipfw_chk(&m, NULL, &rule, 0) == 0) { 773 if (m) 774 m_freem(m); /* dropped; free mbuf chain */ 775 return; /* consumed */ 776 } 777 } 778 #endif 779 eh = mtod(m, struct ether_header *); 780 ether_type = ntohs(eh->ether_type); 781 782 /* 783 * If this frame has a VLAN tag other than 0, call vlan_input() 784 * if its module is loaded. Otherwise, drop. 785 */ 786 if ((m->m_flags & M_VLANTAG) && 787 EVL_VLANOFTAG(m->m_pkthdr.ether_vtag) != 0) { 788 if (ifp->if_vlantrunk == NULL) { 789 ifp->if_noproto++; 790 m_freem(m); 791 return; 792 } 793 KASSERT(vlan_input_p != NULL,("%s: VLAN not loaded!", 794 __func__)); 795 /* Clear before possibly re-entering ether_input(). */ 796 m->m_flags &= ~M_PROMISC; 797 (*vlan_input_p)(ifp, m); 798 return; 799 } 800 801 /* 802 * Pass promiscuously received frames to the upper layer if the user 803 * requested this by setting IFF_PPROMISC. Otherwise, drop them. 804 */ 805 if ((ifp->if_flags & IFF_PPROMISC) == 0 && (m->m_flags & M_PROMISC)) { 806 m_freem(m); 807 return; 808 } 809 810 /* 811 * Reset layer specific mbuf flags to avoid confusing upper layers. 812 * Strip off Ethernet header. 813 */ 814 m->m_flags &= ~M_VLANTAG; 815 m->m_flags &= ~(M_PROTOFLAGS); 816 m_adj(m, ETHER_HDR_LEN); 817 818 /* 819 * Dispatch frame to upper layer. 820 */ 821 switch (ether_type) { 822 #ifdef INET 823 case ETHERTYPE_IP: 824 if ((m = ip_fastforward(m)) == NULL) 825 return; 826 isr = NETISR_IP; 827 break; 828 829 case ETHERTYPE_ARP: 830 if (ifp->if_flags & IFF_NOARP) { 831 /* Discard packet if ARP is disabled on interface */ 832 m_freem(m); 833 return; 834 } 835 isr = NETISR_ARP; 836 break; 837 #endif 838 #ifdef IPX 839 case ETHERTYPE_IPX: 840 if (ef_inputp && ef_inputp(ifp, eh, m) == 0) 841 return; 842 isr = NETISR_IPX; 843 break; 844 #endif 845 #ifdef INET6 846 case ETHERTYPE_IPV6: 847 isr = NETISR_IPV6; 848 break; 849 #endif 850 #ifdef NETATALK 851 case ETHERTYPE_AT: 852 isr = NETISR_ATALK1; 853 break; 854 case ETHERTYPE_AARP: 855 isr = NETISR_AARP; 856 break; 857 #endif /* NETATALK */ 858 default: 859 #ifdef IPX 860 if (ef_inputp && ef_inputp(ifp, eh, m) == 0) 861 return; 862 #endif /* IPX */ 863 #if defined(NETATALK) 864 if (ether_type > ETHERMTU) 865 goto discard; 866 l = mtod(m, struct llc *); 867 if (l->llc_dsap == LLC_SNAP_LSAP && 868 l->llc_ssap == LLC_SNAP_LSAP && 869 l->llc_control == LLC_UI) { 870 if (bcmp(&(l->llc_snap_org_code)[0], at_org_code, 871 sizeof(at_org_code)) == 0 && 872 ntohs(l->llc_snap_ether_type) == ETHERTYPE_AT) { 873 m_adj(m, LLC_SNAPFRAMELEN); 874 isr = NETISR_ATALK2; 875 break; 876 } 877 if (bcmp(&(l->llc_snap_org_code)[0], aarp_org_code, 878 sizeof(aarp_org_code)) == 0 && 879 ntohs(l->llc_snap_ether_type) == ETHERTYPE_AARP) { 880 m_adj(m, LLC_SNAPFRAMELEN); 881 isr = NETISR_AARP; 882 break; 883 } 884 } 885 #endif /* NETATALK */ 886 goto discard; 887 } 888 netisr_dispatch(isr, m); 889 return; 890 891 discard: 892 /* 893 * Packet is to be discarded. If netgraph is present, 894 * hand the packet to it for last chance processing; 895 * otherwise dispose of it. 896 */ 897 if (IFP2AC(ifp)->ac_netgraph != NULL) { 898 KASSERT(ng_ether_input_orphan_p != NULL, 899 ("ng_ether_input_orphan_p is NULL")); 900 /* 901 * Put back the ethernet header so netgraph has a 902 * consistent view of inbound packets. 903 */ 904 M_PREPEND(m, ETHER_HDR_LEN, M_DONTWAIT); 905 (*ng_ether_input_orphan_p)(ifp, m); 906 return; 907 } 908 m_freem(m); 909 } 910 911 /* 912 * Convert Ethernet address to printable (loggable) representation. 913 * This routine is for compatibility; it's better to just use 914 * 915 * printf("%6D", <pointer to address>, ":"); 916 * 917 * since there's no static buffer involved. 918 */ 919 char * 920 ether_sprintf(const u_char *ap) 921 { 922 static char etherbuf[18]; 923 snprintf(etherbuf, sizeof (etherbuf), "%6D", ap, ":"); 924 return (etherbuf); 925 } 926 927 /* 928 * Perform common duties while attaching to interface list 929 */ 930 void 931 ether_ifattach(struct ifnet *ifp, const u_int8_t *lla) 932 { 933 int i; 934 struct ifaddr *ifa; 935 struct sockaddr_dl *sdl; 936 937 ifp->if_addrlen = ETHER_ADDR_LEN; 938 ifp->if_hdrlen = ETHER_HDR_LEN; 939 if_attach(ifp); 940 ifp->if_mtu = ETHERMTU; 941 ifp->if_output = ether_output; 942 ifp->if_input = ether_input; 943 ifp->if_resolvemulti = ether_resolvemulti; 944 if (ifp->if_baudrate == 0) 945 ifp->if_baudrate = IF_Mbps(10); /* just a default */ 946 ifp->if_broadcastaddr = etherbroadcastaddr; 947 948 ifa = ifp->if_addr; 949 KASSERT(ifa != NULL, ("%s: no lladdr!\n", __func__)); 950 sdl = (struct sockaddr_dl *)ifa->ifa_addr; 951 sdl->sdl_type = IFT_ETHER; 952 sdl->sdl_alen = ifp->if_addrlen; 953 bcopy(lla, LLADDR(sdl), ifp->if_addrlen); 954 955 bpfattach(ifp, DLT_EN10MB, ETHER_HDR_LEN); 956 if (ng_ether_attach_p != NULL) 957 (*ng_ether_attach_p)(ifp); 958 959 /* Announce Ethernet MAC address if non-zero. */ 960 for (i = 0; i < ifp->if_addrlen; i++) 961 if (lla[i] != 0) 962 break; 963 if (i != ifp->if_addrlen) 964 if_printf(ifp, "Ethernet address: %6D\n", lla, ":"); 965 } 966 967 /* 968 * Perform common duties while detaching an Ethernet interface 969 */ 970 void 971 ether_ifdetach(struct ifnet *ifp) 972 { 973 if (IFP2AC(ifp)->ac_netgraph != NULL) { 974 KASSERT(ng_ether_detach_p != NULL, 975 ("ng_ether_detach_p is NULL")); 976 (*ng_ether_detach_p)(ifp); 977 } 978 979 bpfdetach(ifp); 980 if_detach(ifp); 981 } 982 983 SYSCTL_DECL(_net_link); 984 SYSCTL_NODE(_net_link, IFT_ETHER, ether, CTLFLAG_RW, 0, "Ethernet"); 985 #if defined(INET) || defined(INET6) 986 SYSCTL_V_INT(V_NET, vnet_net, _net_link_ether, OID_AUTO, ipfw, CTLFLAG_RW, 987 ether_ipfw, 0, "Pass ether pkts through firewall"); 988 #endif 989 990 #if 0 991 /* 992 * This is for reference. We have a table-driven version 993 * of the little-endian crc32 generator, which is faster 994 * than the double-loop. 995 */ 996 uint32_t 997 ether_crc32_le(const uint8_t *buf, size_t len) 998 { 999 size_t i; 1000 uint32_t crc; 1001 int bit; 1002 uint8_t data; 1003 1004 crc = 0xffffffff; /* initial value */ 1005 1006 for (i = 0; i < len; i++) { 1007 for (data = *buf++, bit = 0; bit < 8; bit++, data >>= 1) { 1008 carry = (crc ^ data) & 1; 1009 crc >>= 1; 1010 if (carry) 1011 crc = (crc ^ ETHER_CRC_POLY_LE); 1012 } 1013 } 1014 1015 return (crc); 1016 } 1017 #else 1018 uint32_t 1019 ether_crc32_le(const uint8_t *buf, size_t len) 1020 { 1021 static const uint32_t crctab[] = { 1022 0x00000000, 0x1db71064, 0x3b6e20c8, 0x26d930ac, 1023 0x76dc4190, 0x6b6b51f4, 0x4db26158, 0x5005713c, 1024 0xedb88320, 0xf00f9344, 0xd6d6a3e8, 0xcb61b38c, 1025 0x9b64c2b0, 0x86d3d2d4, 0xa00ae278, 0xbdbdf21c 1026 }; 1027 size_t i; 1028 uint32_t crc; 1029 1030 crc = 0xffffffff; /* initial value */ 1031 1032 for (i = 0; i < len; i++) { 1033 crc ^= buf[i]; 1034 crc = (crc >> 4) ^ crctab[crc & 0xf]; 1035 crc = (crc >> 4) ^ crctab[crc & 0xf]; 1036 } 1037 1038 return (crc); 1039 } 1040 #endif 1041 1042 uint32_t 1043 ether_crc32_be(const uint8_t *buf, size_t len) 1044 { 1045 size_t i; 1046 uint32_t crc, carry; 1047 int bit; 1048 uint8_t data; 1049 1050 crc = 0xffffffff; /* initial value */ 1051 1052 for (i = 0; i < len; i++) { 1053 for (data = *buf++, bit = 0; bit < 8; bit++, data >>= 1) { 1054 carry = ((crc & 0x80000000) ? 1 : 0) ^ (data & 0x01); 1055 crc <<= 1; 1056 if (carry) 1057 crc = (crc ^ ETHER_CRC_POLY_BE) | carry; 1058 } 1059 } 1060 1061 return (crc); 1062 } 1063 1064 int 1065 ether_ioctl(struct ifnet *ifp, u_long command, caddr_t data) 1066 { 1067 struct ifaddr *ifa = (struct ifaddr *) data; 1068 struct ifreq *ifr = (struct ifreq *) data; 1069 int error = 0; 1070 1071 switch (command) { 1072 case SIOCSIFADDR: 1073 ifp->if_flags |= IFF_UP; 1074 1075 switch (ifa->ifa_addr->sa_family) { 1076 #ifdef INET 1077 case AF_INET: 1078 ifp->if_init(ifp->if_softc); /* before arpwhohas */ 1079 arp_ifinit(ifp, ifa); 1080 break; 1081 #endif 1082 #ifdef IPX 1083 /* 1084 * XXX - This code is probably wrong 1085 */ 1086 case AF_IPX: 1087 { 1088 struct ipx_addr *ina = &(IA_SIPX(ifa)->sipx_addr); 1089 1090 if (ipx_nullhost(*ina)) 1091 ina->x_host = 1092 *(union ipx_host *) 1093 IF_LLADDR(ifp); 1094 else { 1095 bcopy((caddr_t) ina->x_host.c_host, 1096 (caddr_t) IF_LLADDR(ifp), 1097 ETHER_ADDR_LEN); 1098 } 1099 1100 /* 1101 * Set new address 1102 */ 1103 ifp->if_init(ifp->if_softc); 1104 break; 1105 } 1106 #endif 1107 default: 1108 ifp->if_init(ifp->if_softc); 1109 break; 1110 } 1111 break; 1112 1113 case SIOCGIFADDR: 1114 { 1115 struct sockaddr *sa; 1116 1117 sa = (struct sockaddr *) & ifr->ifr_data; 1118 bcopy(IF_LLADDR(ifp), 1119 (caddr_t) sa->sa_data, ETHER_ADDR_LEN); 1120 } 1121 break; 1122 1123 case SIOCSIFMTU: 1124 /* 1125 * Set the interface MTU. 1126 */ 1127 if (ifr->ifr_mtu > ETHERMTU) { 1128 error = EINVAL; 1129 } else { 1130 ifp->if_mtu = ifr->ifr_mtu; 1131 } 1132 break; 1133 default: 1134 error = EINVAL; /* XXX netbsd has ENOTTY??? */ 1135 break; 1136 } 1137 return (error); 1138 } 1139 1140 static int 1141 ether_resolvemulti(struct ifnet *ifp, struct sockaddr **llsa, 1142 struct sockaddr *sa) 1143 { 1144 struct sockaddr_dl *sdl; 1145 #ifdef INET 1146 struct sockaddr_in *sin; 1147 #endif 1148 #ifdef INET6 1149 struct sockaddr_in6 *sin6; 1150 #endif 1151 u_char *e_addr; 1152 1153 switch(sa->sa_family) { 1154 case AF_LINK: 1155 /* 1156 * No mapping needed. Just check that it's a valid MC address. 1157 */ 1158 sdl = (struct sockaddr_dl *)sa; 1159 e_addr = LLADDR(sdl); 1160 if (!ETHER_IS_MULTICAST(e_addr)) 1161 return EADDRNOTAVAIL; 1162 *llsa = 0; 1163 return 0; 1164 1165 #ifdef INET 1166 case AF_INET: 1167 sin = (struct sockaddr_in *)sa; 1168 if (!IN_MULTICAST(ntohl(sin->sin_addr.s_addr))) 1169 return EADDRNOTAVAIL; 1170 sdl = malloc(sizeof *sdl, M_IFMADDR, 1171 M_NOWAIT|M_ZERO); 1172 if (sdl == NULL) 1173 return ENOMEM; 1174 sdl->sdl_len = sizeof *sdl; 1175 sdl->sdl_family = AF_LINK; 1176 sdl->sdl_index = ifp->if_index; 1177 sdl->sdl_type = IFT_ETHER; 1178 sdl->sdl_alen = ETHER_ADDR_LEN; 1179 e_addr = LLADDR(sdl); 1180 ETHER_MAP_IP_MULTICAST(&sin->sin_addr, e_addr); 1181 *llsa = (struct sockaddr *)sdl; 1182 return 0; 1183 #endif 1184 #ifdef INET6 1185 case AF_INET6: 1186 sin6 = (struct sockaddr_in6 *)sa; 1187 if (IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr)) { 1188 /* 1189 * An IP6 address of 0 means listen to all 1190 * of the Ethernet multicast address used for IP6. 1191 * (This is used for multicast routers.) 1192 */ 1193 ifp->if_flags |= IFF_ALLMULTI; 1194 *llsa = 0; 1195 return 0; 1196 } 1197 if (!IN6_IS_ADDR_MULTICAST(&sin6->sin6_addr)) 1198 return EADDRNOTAVAIL; 1199 sdl = malloc(sizeof *sdl, M_IFMADDR, 1200 M_NOWAIT|M_ZERO); 1201 if (sdl == NULL) 1202 return (ENOMEM); 1203 sdl->sdl_len = sizeof *sdl; 1204 sdl->sdl_family = AF_LINK; 1205 sdl->sdl_index = ifp->if_index; 1206 sdl->sdl_type = IFT_ETHER; 1207 sdl->sdl_alen = ETHER_ADDR_LEN; 1208 e_addr = LLADDR(sdl); 1209 ETHER_MAP_IPV6_MULTICAST(&sin6->sin6_addr, e_addr); 1210 *llsa = (struct sockaddr *)sdl; 1211 return 0; 1212 #endif 1213 1214 default: 1215 /* 1216 * Well, the text isn't quite right, but it's the name 1217 * that counts... 1218 */ 1219 return EAFNOSUPPORT; 1220 } 1221 } 1222 1223 static void* 1224 ether_alloc(u_char type, struct ifnet *ifp) 1225 { 1226 struct arpcom *ac; 1227 1228 ac = malloc(sizeof(struct arpcom), M_ARPCOM, M_WAITOK | M_ZERO); 1229 ac->ac_ifp = ifp; 1230 1231 return (ac); 1232 } 1233 1234 static void 1235 ether_free(void *com, u_char type) 1236 { 1237 1238 free(com, M_ARPCOM); 1239 } 1240 1241 static int 1242 ether_modevent(module_t mod, int type, void *data) 1243 { 1244 1245 switch (type) { 1246 case MOD_LOAD: 1247 if_register_com_alloc(IFT_ETHER, ether_alloc, ether_free); 1248 break; 1249 case MOD_UNLOAD: 1250 if_deregister_com_alloc(IFT_ETHER); 1251 break; 1252 default: 1253 return EOPNOTSUPP; 1254 } 1255 1256 return (0); 1257 } 1258 1259 static moduledata_t ether_mod = { 1260 "ether", 1261 ether_modevent, 1262 0 1263 }; 1264 1265 void 1266 ether_vlan_mtap(struct bpf_if *bp, struct mbuf *m, void *data, u_int dlen) 1267 { 1268 struct ether_vlan_header vlan; 1269 struct mbuf mv, mb; 1270 1271 KASSERT((m->m_flags & M_VLANTAG) != 0, 1272 ("%s: vlan information not present", __func__)); 1273 KASSERT(m->m_len >= sizeof(struct ether_header), 1274 ("%s: mbuf not large enough for header", __func__)); 1275 bcopy(mtod(m, char *), &vlan, sizeof(struct ether_header)); 1276 vlan.evl_proto = vlan.evl_encap_proto; 1277 vlan.evl_encap_proto = htons(ETHERTYPE_VLAN); 1278 vlan.evl_tag = htons(m->m_pkthdr.ether_vtag); 1279 m->m_len -= sizeof(struct ether_header); 1280 m->m_data += sizeof(struct ether_header); 1281 /* 1282 * If a data link has been supplied by the caller, then we will need to 1283 * re-create a stack allocated mbuf chain with the following structure: 1284 * 1285 * (1) mbuf #1 will contain the supplied data link 1286 * (2) mbuf #2 will contain the vlan header 1287 * (3) mbuf #3 will contain the original mbuf's packet data 1288 * 1289 * Otherwise, submit the packet and vlan header via bpf_mtap2(). 1290 */ 1291 if (data != NULL) { 1292 mv.m_next = m; 1293 mv.m_data = (caddr_t)&vlan; 1294 mv.m_len = sizeof(vlan); 1295 mb.m_next = &mv; 1296 mb.m_data = data; 1297 mb.m_len = dlen; 1298 bpf_mtap(bp, &mb); 1299 } else 1300 bpf_mtap2(bp, &vlan, sizeof(vlan), m); 1301 m->m_len += sizeof(struct ether_header); 1302 m->m_data -= sizeof(struct ether_header); 1303 } 1304 1305 struct mbuf * 1306 ether_vlanencap(struct mbuf *m, uint16_t tag) 1307 { 1308 struct ether_vlan_header *evl; 1309 1310 M_PREPEND(m, ETHER_VLAN_ENCAP_LEN, M_DONTWAIT); 1311 if (m == NULL) 1312 return (NULL); 1313 /* M_PREPEND takes care of m_len, m_pkthdr.len for us */ 1314 1315 if (m->m_len < sizeof(*evl)) { 1316 m = m_pullup(m, sizeof(*evl)); 1317 if (m == NULL) 1318 return (NULL); 1319 } 1320 1321 /* 1322 * Transform the Ethernet header into an Ethernet header 1323 * with 802.1Q encapsulation. 1324 */ 1325 evl = mtod(m, struct ether_vlan_header *); 1326 bcopy((char *)evl + ETHER_VLAN_ENCAP_LEN, 1327 (char *)evl, ETHER_HDR_LEN - ETHER_TYPE_LEN); 1328 evl->evl_encap_proto = htons(ETHERTYPE_VLAN); 1329 evl->evl_tag = htons(tag); 1330 return (m); 1331 } 1332 1333 DECLARE_MODULE(ether, ether_mod, SI_SUB_INIT_IF, SI_ORDER_ANY); 1334 MODULE_VERSION(ether, 1); 1335