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_netgraph.h" 38 #include "opt_carp.h" 39 #include "opt_mbuf_profiling.h" 40 41 #include <sys/param.h> 42 #include <sys/systm.h> 43 #include <sys/kernel.h> 44 #include <sys/lock.h> 45 #include <sys/malloc.h> 46 #include <sys/module.h> 47 #include <sys/mbuf.h> 48 #include <sys/random.h> 49 #include <sys/rwlock.h> 50 #include <sys/socket.h> 51 #include <sys/sockio.h> 52 #include <sys/sysctl.h> 53 54 #include <net/if.h> 55 #include <net/if_arp.h> 56 #include <net/netisr.h> 57 #include <net/route.h> 58 #include <net/if_llc.h> 59 #include <net/if_dl.h> 60 #include <net/if_types.h> 61 #include <net/bpf.h> 62 #include <net/ethernet.h> 63 #include <net/if_bridgevar.h> 64 #include <net/if_vlan_var.h> 65 #include <net/if_llatbl.h> 66 #include <net/pf_mtag.h> 67 #include <net/vnet.h> 68 69 #if defined(INET) || defined(INET6) 70 #include <netinet/in.h> 71 #include <netinet/in_var.h> 72 #include <netinet/if_ether.h> 73 #include <netinet/ip_fw.h> 74 #include <netinet/ipfw/ip_fw_private.h> 75 #include <netinet/ip_dummynet.h> 76 #include <netinet/ip_var.h> 77 #endif 78 #ifdef INET6 79 #include <netinet6/nd6.h> 80 #endif 81 82 #if defined(INET) || defined(INET6) 83 #ifdef DEV_CARP 84 #include <netinet/ip_carp.h> 85 #endif 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, int shared); 151 static VNET_DEFINE(int, ether_ipfw); 152 #define V_ether_ipfw VNET(ether_ipfw) 153 #endif 154 155 156 /* 157 * Ethernet output routine. 158 * Encapsulate a packet of type family for the local net. 159 * Use trailer local net encapsulation if enough data in first 160 * packet leaves a multiple of 512 bytes of data in remainder. 161 */ 162 int 163 ether_output(struct ifnet *ifp, struct mbuf *m, 164 struct sockaddr *dst, struct route *ro) 165 { 166 short type; 167 int error = 0, hdrcmplt = 0; 168 u_char esrc[ETHER_ADDR_LEN], edst[ETHER_ADDR_LEN]; 169 struct llentry *lle = NULL; 170 struct rtentry *rt0 = NULL; 171 struct ether_header *eh; 172 struct pf_mtag *t; 173 int loop_copy = 1; 174 int hlen; /* link layer header length */ 175 176 if (ro != NULL) { 177 if (!(m->m_flags & (M_BCAST | M_MCAST))) 178 lle = ro->ro_lle; 179 rt0 = ro->ro_rt; 180 } 181 #ifdef MAC 182 error = mac_ifnet_check_transmit(ifp, m); 183 if (error) 184 senderr(error); 185 #endif 186 187 M_PROFILE(m); 188 if (ifp->if_flags & IFF_MONITOR) 189 senderr(ENETDOWN); 190 if (!((ifp->if_flags & IFF_UP) && 191 (ifp->if_drv_flags & IFF_DRV_RUNNING))) 192 senderr(ENETDOWN); 193 194 hlen = ETHER_HDR_LEN; 195 switch (dst->sa_family) { 196 #ifdef INET 197 case AF_INET: 198 if (lle != NULL && (lle->la_flags & LLE_VALID)) 199 memcpy(edst, &lle->ll_addr.mac16, sizeof(edst)); 200 else 201 error = arpresolve(ifp, rt0, m, dst, edst, &lle); 202 if (error) 203 return (error == EWOULDBLOCK ? 0 : error); 204 type = htons(ETHERTYPE_IP); 205 break; 206 case AF_ARP: 207 { 208 struct arphdr *ah; 209 ah = mtod(m, struct arphdr *); 210 ah->ar_hrd = htons(ARPHRD_ETHER); 211 212 loop_copy = 0; /* if this is for us, don't do it */ 213 214 switch(ntohs(ah->ar_op)) { 215 case ARPOP_REVREQUEST: 216 case ARPOP_REVREPLY: 217 type = htons(ETHERTYPE_REVARP); 218 break; 219 case ARPOP_REQUEST: 220 case ARPOP_REPLY: 221 default: 222 type = htons(ETHERTYPE_ARP); 223 break; 224 } 225 226 if (m->m_flags & M_BCAST) 227 bcopy(ifp->if_broadcastaddr, edst, ETHER_ADDR_LEN); 228 else 229 bcopy(ar_tha(ah), edst, ETHER_ADDR_LEN); 230 231 } 232 break; 233 #endif 234 #ifdef INET6 235 case AF_INET6: 236 if (lle != NULL && (lle->la_flags & LLE_VALID)) 237 memcpy(edst, &lle->ll_addr.mac16, sizeof(edst)); 238 else 239 error = nd6_storelladdr(ifp, m, dst, (u_char *)edst, &lle); 240 if (error) 241 return error; 242 type = htons(ETHERTYPE_IPV6); 243 break; 244 #endif 245 #ifdef IPX 246 case AF_IPX: 247 if (ef_outputp) { 248 error = ef_outputp(ifp, &m, dst, &type, &hlen); 249 if (error) 250 goto bad; 251 } else 252 type = htons(ETHERTYPE_IPX); 253 bcopy((caddr_t)&(((struct sockaddr_ipx *)dst)->sipx_addr.x_host), 254 (caddr_t)edst, sizeof (edst)); 255 break; 256 #endif 257 #ifdef NETATALK 258 case AF_APPLETALK: 259 { 260 struct at_ifaddr *aa; 261 262 if ((aa = at_ifawithnet((struct sockaddr_at *)dst)) == NULL) 263 senderr(EHOSTUNREACH); /* XXX */ 264 if (!aarpresolve(ifp, m, (struct sockaddr_at *)dst, edst)) { 265 ifa_free(&aa->aa_ifa); 266 return (0); 267 } 268 /* 269 * In the phase 2 case, need to prepend an mbuf for the llc header. 270 */ 271 if ( aa->aa_flags & AFA_PHASE2 ) { 272 struct llc llc; 273 274 ifa_free(&aa->aa_ifa); 275 M_PREPEND(m, LLC_SNAPFRAMELEN, M_DONTWAIT); 276 if (m == NULL) 277 senderr(ENOBUFS); 278 llc.llc_dsap = llc.llc_ssap = LLC_SNAP_LSAP; 279 llc.llc_control = LLC_UI; 280 bcopy(at_org_code, llc.llc_snap_org_code, sizeof(at_org_code)); 281 llc.llc_snap_ether_type = htons( ETHERTYPE_AT ); 282 bcopy(&llc, mtod(m, caddr_t), LLC_SNAPFRAMELEN); 283 type = htons(m->m_pkthdr.len); 284 hlen = LLC_SNAPFRAMELEN + ETHER_HDR_LEN; 285 } else { 286 ifa_free(&aa->aa_ifa); 287 type = htons(ETHERTYPE_AT); 288 } 289 break; 290 } 291 #endif /* NETATALK */ 292 293 case pseudo_AF_HDRCMPLT: 294 hdrcmplt = 1; 295 eh = (struct ether_header *)dst->sa_data; 296 (void)memcpy(esrc, eh->ether_shost, sizeof (esrc)); 297 /* FALLTHROUGH */ 298 299 case AF_UNSPEC: 300 loop_copy = 0; /* if this is for us, don't do it */ 301 eh = (struct ether_header *)dst->sa_data; 302 (void)memcpy(edst, eh->ether_dhost, sizeof (edst)); 303 type = eh->ether_type; 304 break; 305 306 default: 307 if_printf(ifp, "can't handle af%d\n", dst->sa_family); 308 senderr(EAFNOSUPPORT); 309 } 310 311 if (lle != NULL && (lle->la_flags & LLE_IFADDR)) { 312 int csum_flags = 0; 313 if (m->m_pkthdr.csum_flags & CSUM_IP) 314 csum_flags |= (CSUM_IP_CHECKED|CSUM_IP_VALID); 315 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) 316 csum_flags |= (CSUM_DATA_VALID|CSUM_PSEUDO_HDR); 317 if (m->m_pkthdr.csum_flags & CSUM_SCTP) 318 csum_flags |= CSUM_SCTP_VALID; 319 m->m_pkthdr.csum_flags |= csum_flags; 320 m->m_pkthdr.csum_data = 0xffff; 321 return (if_simloop(ifp, m, dst->sa_family, 0)); 322 } 323 324 /* 325 * Add local net header. If no space in first mbuf, 326 * allocate another. 327 */ 328 M_PREPEND(m, ETHER_HDR_LEN, M_DONTWAIT); 329 if (m == NULL) 330 senderr(ENOBUFS); 331 eh = mtod(m, struct ether_header *); 332 (void)memcpy(&eh->ether_type, &type, 333 sizeof(eh->ether_type)); 334 (void)memcpy(eh->ether_dhost, edst, sizeof (edst)); 335 if (hdrcmplt) 336 (void)memcpy(eh->ether_shost, esrc, 337 sizeof(eh->ether_shost)); 338 else 339 (void)memcpy(eh->ether_shost, IF_LLADDR(ifp), 340 sizeof(eh->ether_shost)); 341 342 /* 343 * If a simplex interface, and the packet is being sent to our 344 * Ethernet address or a broadcast address, loopback a copy. 345 * XXX To make a simplex device behave exactly like a duplex 346 * device, we should copy in the case of sending to our own 347 * ethernet address (thus letting the original actually appear 348 * on the wire). However, we don't do that here for security 349 * reasons and compatibility with the original behavior. 350 */ 351 if ((ifp->if_flags & IFF_SIMPLEX) && loop_copy && 352 ((t = pf_find_mtag(m)) == NULL || !t->routed)) { 353 int csum_flags = 0; 354 355 if (m->m_pkthdr.csum_flags & CSUM_IP) 356 csum_flags |= (CSUM_IP_CHECKED|CSUM_IP_VALID); 357 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) 358 csum_flags |= (CSUM_DATA_VALID|CSUM_PSEUDO_HDR); 359 if (m->m_pkthdr.csum_flags & CSUM_SCTP) 360 csum_flags |= CSUM_SCTP_VALID; 361 362 if (m->m_flags & M_BCAST) { 363 struct mbuf *n; 364 365 /* 366 * Because if_simloop() modifies the packet, we need a 367 * writable copy through m_dup() instead of a readonly 368 * one as m_copy[m] would give us. The alternative would 369 * be to modify if_simloop() to handle the readonly mbuf, 370 * but performancewise it is mostly equivalent (trading 371 * extra data copying vs. extra locking). 372 * 373 * XXX This is a local workaround. A number of less 374 * often used kernel parts suffer from the same bug. 375 * See PR kern/105943 for a proposed general solution. 376 */ 377 if ((n = m_dup(m, M_DONTWAIT)) != NULL) { 378 n->m_pkthdr.csum_flags |= csum_flags; 379 if (csum_flags & CSUM_DATA_VALID) 380 n->m_pkthdr.csum_data = 0xffff; 381 (void)if_simloop(ifp, n, dst->sa_family, hlen); 382 } else 383 ifp->if_iqdrops++; 384 } else if (bcmp(eh->ether_dhost, eh->ether_shost, 385 ETHER_ADDR_LEN) == 0) { 386 m->m_pkthdr.csum_flags |= csum_flags; 387 if (csum_flags & CSUM_DATA_VALID) 388 m->m_pkthdr.csum_data = 0xffff; 389 (void) if_simloop(ifp, m, dst->sa_family, hlen); 390 return (0); /* XXX */ 391 } 392 } 393 394 /* 395 * Bridges require special output handling. 396 */ 397 if (ifp->if_bridge) { 398 BRIDGE_OUTPUT(ifp, m, error); 399 return (error); 400 } 401 402 #if defined(INET) || defined(INET6) 403 #ifdef DEV_CARP 404 if (ifp->if_carp && 405 (error = carp_output(ifp, m, dst, NULL))) 406 goto bad; 407 #endif 408 #endif 409 410 /* Handle ng_ether(4) processing, if any */ 411 if (IFP2AC(ifp)->ac_netgraph != NULL) { 412 KASSERT(ng_ether_output_p != NULL, 413 ("ng_ether_output_p is NULL")); 414 if ((error = (*ng_ether_output_p)(ifp, &m)) != 0) { 415 bad: if (m != NULL) 416 m_freem(m); 417 return (error); 418 } 419 if (m == NULL) 420 return (0); 421 } 422 423 /* Continue with link-layer output */ 424 return ether_output_frame(ifp, m); 425 } 426 427 /* 428 * Ethernet link layer output routine to send a raw frame to the device. 429 * 430 * This assumes that the 14 byte Ethernet header is present and contiguous 431 * in the first mbuf (if BRIDGE'ing). 432 */ 433 int 434 ether_output_frame(struct ifnet *ifp, struct mbuf *m) 435 { 436 #if defined(INET) || defined(INET6) 437 438 if (V_ip_fw_chk_ptr && V_ether_ipfw != 0) { 439 if (ether_ipfw_chk(&m, ifp, 0) == 0) { 440 if (m) { 441 m_freem(m); 442 return EACCES; /* pkt dropped */ 443 } else 444 return 0; /* consumed e.g. in a pipe */ 445 } 446 } 447 #endif 448 449 /* 450 * Queue message on interface, update output statistics if 451 * successful, and start output if interface not yet active. 452 */ 453 return ((ifp->if_transmit)(ifp, m)); 454 } 455 456 #if defined(INET) || defined(INET6) 457 /* 458 * ipfw processing for ethernet packets (in and out). 459 * The second parameter is NULL from ether_demux, and ifp from 460 * ether_output_frame. 461 */ 462 int 463 ether_ipfw_chk(struct mbuf **m0, struct ifnet *dst, int shared) 464 { 465 struct ether_header *eh; 466 struct ether_header save_eh; 467 struct mbuf *m; 468 int i; 469 struct ip_fw_args args; 470 struct m_tag *mtag; 471 472 mtag = m_tag_find(*m0, PACKET_TAG_DUMMYNET, NULL); 473 if (mtag == NULL) { 474 args.slot = 0; 475 } else { 476 struct dn_pkt_tag *dn_tag; 477 478 mtag->m_tag_id = PACKET_TAG_NONE; 479 dn_tag = (struct dn_pkt_tag *)(mtag + 1); 480 if (dn_tag->slot != 0 && V_fw_one_pass) 481 /* dummynet packet, already partially processed */ 482 return (1); 483 args.slot = dn_tag->slot; /* matching rule to restart */ 484 args.rulenum = dn_tag->rulenum; 485 args.rule_id = dn_tag->rule_id; 486 args.chain_id = dn_tag->chain_id; 487 } 488 489 /* 490 * I need some amt of data to be contiguous, and in case others need 491 * the packet (shared==1) also better be in the first mbuf. 492 */ 493 m = *m0; 494 i = min( m->m_pkthdr.len, max_protohdr); 495 if ( shared || m->m_len < i) { 496 m = m_pullup(m, i); 497 if (m == NULL) { 498 *m0 = m; 499 return 0; 500 } 501 } 502 eh = mtod(m, struct ether_header *); 503 save_eh = *eh; /* save copy for restore below */ 504 m_adj(m, ETHER_HDR_LEN); /* strip ethernet header */ 505 506 args.m = m; /* the packet we are looking at */ 507 args.oif = dst; /* destination, if any */ 508 args.next_hop = NULL; /* we do not support forward yet */ 509 args.eh = &save_eh; /* MAC header for bridged/MAC packets */ 510 args.inp = NULL; /* used by ipfw uid/gid/jail rules */ 511 i = V_ip_fw_chk_ptr(&args); 512 m = args.m; 513 if (m != NULL) { 514 /* 515 * Restore Ethernet header, as needed, in case the 516 * mbuf chain was replaced by ipfw. 517 */ 518 M_PREPEND(m, ETHER_HDR_LEN, M_DONTWAIT); 519 if (m == NULL) { 520 *m0 = m; 521 return 0; 522 } 523 if (eh != mtod(m, struct ether_header *)) 524 bcopy(&save_eh, mtod(m, struct ether_header *), 525 ETHER_HDR_LEN); 526 } 527 *m0 = m; 528 529 if (i == IP_FW_DENY) /* drop */ 530 return 0; 531 532 KASSERT(m != NULL, ("ether_ipfw_chk: m is NULL")); 533 534 if (i == IP_FW_PASS) /* a PASS rule. */ 535 return 1; 536 537 if (ip_dn_io_ptr && (i == IP_FW_DUMMYNET)) { 538 int dir; 539 /* 540 * Pass the pkt to dummynet, which consumes it. 541 * If shared, make a copy and keep the original. 542 */ 543 if (shared) { 544 m = m_copypacket(m, M_DONTWAIT); 545 if (m == NULL) 546 return 0; 547 } else { 548 /* 549 * Pass the original to dummynet and 550 * nothing back to the caller 551 */ 552 *m0 = NULL ; 553 } 554 dir = PROTO_LAYER2 | (dst ? DIR_OUT : DIR_IN); 555 ip_dn_io_ptr(&m, dir, &args); 556 return 0; 557 } 558 /* 559 * XXX at some point add support for divert/forward actions. 560 * If none of the above matches, we have to drop the pkt. 561 */ 562 return 0; 563 } 564 #endif 565 566 /* 567 * Process a received Ethernet packet; the packet is in the 568 * mbuf chain m with the ethernet header at the front. 569 */ 570 static void 571 ether_input(struct ifnet *ifp, struct mbuf *m) 572 { 573 struct ether_header *eh; 574 u_short etype; 575 576 if ((ifp->if_flags & IFF_UP) == 0) { 577 m_freem(m); 578 return; 579 } 580 #ifdef DIAGNOSTIC 581 if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0) { 582 if_printf(ifp, "discard frame at !IFF_DRV_RUNNING\n"); 583 m_freem(m); 584 return; 585 } 586 #endif 587 /* 588 * Do consistency checks to verify assumptions 589 * made by code past this point. 590 */ 591 if ((m->m_flags & M_PKTHDR) == 0) { 592 if_printf(ifp, "discard frame w/o packet header\n"); 593 ifp->if_ierrors++; 594 m_freem(m); 595 return; 596 } 597 if (m->m_len < ETHER_HDR_LEN) { 598 /* XXX maybe should pullup? */ 599 if_printf(ifp, "discard frame w/o leading ethernet " 600 "header (len %u pkt len %u)\n", 601 m->m_len, m->m_pkthdr.len); 602 ifp->if_ierrors++; 603 m_freem(m); 604 return; 605 } 606 eh = mtod(m, struct ether_header *); 607 etype = ntohs(eh->ether_type); 608 if (m->m_pkthdr.rcvif == NULL) { 609 if_printf(ifp, "discard frame w/o interface pointer\n"); 610 ifp->if_ierrors++; 611 m_freem(m); 612 return; 613 } 614 #ifdef DIAGNOSTIC 615 if (m->m_pkthdr.rcvif != ifp) { 616 if_printf(ifp, "Warning, frame marked as received on %s\n", 617 m->m_pkthdr.rcvif->if_xname); 618 } 619 #endif 620 621 CURVNET_SET_QUIET(ifp->if_vnet); 622 623 if (ETHER_IS_MULTICAST(eh->ether_dhost)) { 624 if (ETHER_IS_BROADCAST(eh->ether_dhost)) 625 m->m_flags |= M_BCAST; 626 else 627 m->m_flags |= M_MCAST; 628 ifp->if_imcasts++; 629 } 630 631 #ifdef MAC 632 /* 633 * Tag the mbuf with an appropriate MAC label before any other 634 * consumers can get to it. 635 */ 636 mac_ifnet_create_mbuf(ifp, m); 637 #endif 638 639 /* 640 * Give bpf a chance at the packet. 641 */ 642 ETHER_BPF_MTAP(ifp, m); 643 644 /* 645 * If the CRC is still on the packet, trim it off. We do this once 646 * and once only in case we are re-entered. Nothing else on the 647 * Ethernet receive path expects to see the FCS. 648 */ 649 if (m->m_flags & M_HASFCS) { 650 m_adj(m, -ETHER_CRC_LEN); 651 m->m_flags &= ~M_HASFCS; 652 } 653 654 ifp->if_ibytes += m->m_pkthdr.len; 655 656 /* Allow monitor mode to claim this frame, after stats are updated. */ 657 if (ifp->if_flags & IFF_MONITOR) { 658 m_freem(m); 659 CURVNET_RESTORE(); 660 return; 661 } 662 663 /* Handle input from a lagg(4) port */ 664 if (ifp->if_type == IFT_IEEE8023ADLAG) { 665 KASSERT(lagg_input_p != NULL, 666 ("%s: if_lagg not loaded!", __func__)); 667 m = (*lagg_input_p)(ifp, m); 668 if (m != NULL) 669 ifp = m->m_pkthdr.rcvif; 670 else 671 return; 672 } 673 674 /* 675 * If the hardware did not process an 802.1Q tag, do this now, 676 * to allow 802.1P priority frames to be passed to the main input 677 * path correctly. 678 * TODO: Deal with Q-in-Q frames, but not arbitrary nesting levels. 679 */ 680 if ((m->m_flags & M_VLANTAG) == 0 && etype == ETHERTYPE_VLAN) { 681 struct ether_vlan_header *evl; 682 683 if (m->m_len < sizeof(*evl) && 684 (m = m_pullup(m, sizeof(*evl))) == NULL) { 685 #ifdef DIAGNOSTIC 686 if_printf(ifp, "cannot pullup VLAN header\n"); 687 #endif 688 ifp->if_ierrors++; 689 m_freem(m); 690 return; 691 } 692 693 evl = mtod(m, struct ether_vlan_header *); 694 m->m_pkthdr.ether_vtag = ntohs(evl->evl_tag); 695 m->m_flags |= M_VLANTAG; 696 697 bcopy((char *)evl, (char *)evl + ETHER_VLAN_ENCAP_LEN, 698 ETHER_HDR_LEN - ETHER_TYPE_LEN); 699 m_adj(m, ETHER_VLAN_ENCAP_LEN); 700 } 701 702 /* Allow ng_ether(4) to claim this frame. */ 703 if (IFP2AC(ifp)->ac_netgraph != NULL) { 704 KASSERT(ng_ether_input_p != NULL, 705 ("%s: ng_ether_input_p is NULL", __func__)); 706 m->m_flags &= ~M_PROMISC; 707 (*ng_ether_input_p)(ifp, &m); 708 if (m == NULL) { 709 CURVNET_RESTORE(); 710 return; 711 } 712 } 713 714 /* 715 * Allow if_bridge(4) to claim this frame. 716 * The BRIDGE_INPUT() macro will update ifp if the bridge changed it 717 * and the frame should be delivered locally. 718 */ 719 if (ifp->if_bridge != NULL) { 720 m->m_flags &= ~M_PROMISC; 721 BRIDGE_INPUT(ifp, m); 722 if (m == NULL) { 723 CURVNET_RESTORE(); 724 return; 725 } 726 } 727 728 #if defined(INET) || defined(INET6) 729 #ifdef DEV_CARP 730 /* 731 * Clear M_PROMISC on frame so that carp(4) will see it when the 732 * mbuf flows up to Layer 3. 733 * FreeBSD's implementation of carp(4) uses the inprotosw 734 * to dispatch IPPROTO_CARP. carp(4) also allocates its own 735 * Ethernet addresses of the form 00:00:5e:00:01:xx, which 736 * is outside the scope of the M_PROMISC test below. 737 * TODO: Maintain a hash table of ethernet addresses other than 738 * ether_dhost which may be active on this ifp. 739 */ 740 if (ifp->if_carp && carp_forus(ifp->if_carp, eh->ether_dhost)) { 741 m->m_flags &= ~M_PROMISC; 742 } else 743 #endif 744 #endif 745 { 746 /* 747 * If the frame received was not for our MAC address, set the 748 * M_PROMISC flag on the mbuf chain. The frame may need to 749 * be seen by the rest of the Ethernet input path in case of 750 * re-entry (e.g. bridge, vlan, netgraph) but should not be 751 * seen by upper protocol layers. 752 */ 753 if (!ETHER_IS_MULTICAST(eh->ether_dhost) && 754 bcmp(IF_LLADDR(ifp), eh->ether_dhost, ETHER_ADDR_LEN) != 0) 755 m->m_flags |= M_PROMISC; 756 } 757 758 /* First chunk of an mbuf contains good entropy */ 759 if (harvest.ethernet) 760 random_harvest(m, 16, 3, 0, RANDOM_NET); 761 762 ether_demux(ifp, m); 763 CURVNET_RESTORE(); 764 } 765 766 /* 767 * Upper layer processing for a received Ethernet packet. 768 */ 769 void 770 ether_demux(struct ifnet *ifp, struct mbuf *m) 771 { 772 struct ether_header *eh; 773 int isr; 774 u_short ether_type; 775 #if defined(NETATALK) 776 struct llc *l; 777 #endif 778 779 KASSERT(ifp != NULL, ("%s: NULL interface pointer", __func__)); 780 781 #if defined(INET) || defined(INET6) 782 /* 783 * Allow dummynet and/or ipfw to claim the frame. 784 * Do not do this for PROMISC frames in case we are re-entered. 785 */ 786 if (V_ip_fw_chk_ptr && V_ether_ipfw != 0 && !(m->m_flags & M_PROMISC)) { 787 if (ether_ipfw_chk(&m, NULL, 0) == 0) { 788 if (m) 789 m_freem(m); /* dropped; free mbuf chain */ 790 return; /* consumed */ 791 } 792 } 793 #endif 794 eh = mtod(m, struct ether_header *); 795 ether_type = ntohs(eh->ether_type); 796 797 /* 798 * If this frame has a VLAN tag other than 0, call vlan_input() 799 * if its module is loaded. Otherwise, drop. 800 */ 801 if ((m->m_flags & M_VLANTAG) && 802 EVL_VLANOFTAG(m->m_pkthdr.ether_vtag) != 0) { 803 if (ifp->if_vlantrunk == NULL) { 804 ifp->if_noproto++; 805 m_freem(m); 806 return; 807 } 808 KASSERT(vlan_input_p != NULL,("%s: VLAN not loaded!", 809 __func__)); 810 /* Clear before possibly re-entering ether_input(). */ 811 m->m_flags &= ~M_PROMISC; 812 (*vlan_input_p)(ifp, m); 813 return; 814 } 815 816 /* 817 * Pass promiscuously received frames to the upper layer if the user 818 * requested this by setting IFF_PPROMISC. Otherwise, drop them. 819 */ 820 if ((ifp->if_flags & IFF_PPROMISC) == 0 && (m->m_flags & M_PROMISC)) { 821 m_freem(m); 822 return; 823 } 824 825 /* 826 * Reset layer specific mbuf flags to avoid confusing upper layers. 827 * Strip off Ethernet header. 828 */ 829 m->m_flags &= ~M_VLANTAG; 830 m->m_flags &= ~(M_PROTOFLAGS); 831 m_adj(m, ETHER_HDR_LEN); 832 833 /* 834 * Dispatch frame to upper layer. 835 */ 836 switch (ether_type) { 837 #ifdef INET 838 case ETHERTYPE_IP: 839 if ((m = ip_fastforward(m)) == NULL) 840 return; 841 isr = NETISR_IP; 842 break; 843 844 case ETHERTYPE_ARP: 845 if (ifp->if_flags & IFF_NOARP) { 846 /* Discard packet if ARP is disabled on interface */ 847 m_freem(m); 848 return; 849 } 850 isr = NETISR_ARP; 851 break; 852 #endif 853 #ifdef IPX 854 case ETHERTYPE_IPX: 855 if (ef_inputp && ef_inputp(ifp, eh, m) == 0) 856 return; 857 isr = NETISR_IPX; 858 break; 859 #endif 860 #ifdef INET6 861 case ETHERTYPE_IPV6: 862 isr = NETISR_IPV6; 863 break; 864 #endif 865 #ifdef NETATALK 866 case ETHERTYPE_AT: 867 isr = NETISR_ATALK1; 868 break; 869 case ETHERTYPE_AARP: 870 isr = NETISR_AARP; 871 break; 872 #endif /* NETATALK */ 873 default: 874 #ifdef IPX 875 if (ef_inputp && ef_inputp(ifp, eh, m) == 0) 876 return; 877 #endif /* IPX */ 878 #if defined(NETATALK) 879 if (ether_type > ETHERMTU) 880 goto discard; 881 l = mtod(m, struct llc *); 882 if (l->llc_dsap == LLC_SNAP_LSAP && 883 l->llc_ssap == LLC_SNAP_LSAP && 884 l->llc_control == LLC_UI) { 885 if (bcmp(&(l->llc_snap_org_code)[0], at_org_code, 886 sizeof(at_org_code)) == 0 && 887 ntohs(l->llc_snap_ether_type) == ETHERTYPE_AT) { 888 m_adj(m, LLC_SNAPFRAMELEN); 889 isr = NETISR_ATALK2; 890 break; 891 } 892 if (bcmp(&(l->llc_snap_org_code)[0], aarp_org_code, 893 sizeof(aarp_org_code)) == 0 && 894 ntohs(l->llc_snap_ether_type) == ETHERTYPE_AARP) { 895 m_adj(m, LLC_SNAPFRAMELEN); 896 isr = NETISR_AARP; 897 break; 898 } 899 } 900 #endif /* NETATALK */ 901 goto discard; 902 } 903 netisr_dispatch(isr, m); 904 return; 905 906 discard: 907 /* 908 * Packet is to be discarded. If netgraph is present, 909 * hand the packet to it for last chance processing; 910 * otherwise dispose of it. 911 */ 912 if (IFP2AC(ifp)->ac_netgraph != NULL) { 913 KASSERT(ng_ether_input_orphan_p != NULL, 914 ("ng_ether_input_orphan_p is NULL")); 915 /* 916 * Put back the ethernet header so netgraph has a 917 * consistent view of inbound packets. 918 */ 919 M_PREPEND(m, ETHER_HDR_LEN, M_DONTWAIT); 920 (*ng_ether_input_orphan_p)(ifp, m); 921 return; 922 } 923 m_freem(m); 924 } 925 926 /* 927 * Convert Ethernet address to printable (loggable) representation. 928 * This routine is for compatibility; it's better to just use 929 * 930 * printf("%6D", <pointer to address>, ":"); 931 * 932 * since there's no static buffer involved. 933 */ 934 char * 935 ether_sprintf(const u_char *ap) 936 { 937 static char etherbuf[18]; 938 snprintf(etherbuf, sizeof (etherbuf), "%6D", ap, ":"); 939 return (etherbuf); 940 } 941 942 /* 943 * Perform common duties while attaching to interface list 944 */ 945 void 946 ether_ifattach(struct ifnet *ifp, const u_int8_t *lla) 947 { 948 int i; 949 struct ifaddr *ifa; 950 struct sockaddr_dl *sdl; 951 952 ifp->if_addrlen = ETHER_ADDR_LEN; 953 ifp->if_hdrlen = ETHER_HDR_LEN; 954 if_attach(ifp); 955 ifp->if_mtu = ETHERMTU; 956 ifp->if_output = ether_output; 957 ifp->if_input = ether_input; 958 ifp->if_resolvemulti = ether_resolvemulti; 959 if (ifp->if_baudrate == 0) 960 ifp->if_baudrate = IF_Mbps(10); /* just a default */ 961 ifp->if_broadcastaddr = etherbroadcastaddr; 962 963 ifa = ifp->if_addr; 964 KASSERT(ifa != NULL, ("%s: no lladdr!\n", __func__)); 965 sdl = (struct sockaddr_dl *)ifa->ifa_addr; 966 sdl->sdl_type = IFT_ETHER; 967 sdl->sdl_alen = ifp->if_addrlen; 968 bcopy(lla, LLADDR(sdl), ifp->if_addrlen); 969 970 bpfattach(ifp, DLT_EN10MB, ETHER_HDR_LEN); 971 if (ng_ether_attach_p != NULL) 972 (*ng_ether_attach_p)(ifp); 973 974 /* Announce Ethernet MAC address if non-zero. */ 975 for (i = 0; i < ifp->if_addrlen; i++) 976 if (lla[i] != 0) 977 break; 978 if (i != ifp->if_addrlen) 979 if_printf(ifp, "Ethernet address: %6D\n", lla, ":"); 980 } 981 982 /* 983 * Perform common duties while detaching an Ethernet interface 984 */ 985 void 986 ether_ifdetach(struct ifnet *ifp) 987 { 988 if (IFP2AC(ifp)->ac_netgraph != NULL) { 989 KASSERT(ng_ether_detach_p != NULL, 990 ("ng_ether_detach_p is NULL")); 991 (*ng_ether_detach_p)(ifp); 992 } 993 994 bpfdetach(ifp); 995 if_detach(ifp); 996 } 997 998 SYSCTL_DECL(_net_link); 999 SYSCTL_NODE(_net_link, IFT_ETHER, ether, CTLFLAG_RW, 0, "Ethernet"); 1000 #if defined(INET) || defined(INET6) 1001 SYSCTL_VNET_INT(_net_link_ether, OID_AUTO, ipfw, CTLFLAG_RW, 1002 &VNET_NAME(ether_ipfw), 0, "Pass ether pkts through firewall"); 1003 #endif 1004 1005 #if 0 1006 /* 1007 * This is for reference. We have a table-driven version 1008 * of the little-endian crc32 generator, which is faster 1009 * than the double-loop. 1010 */ 1011 uint32_t 1012 ether_crc32_le(const uint8_t *buf, size_t len) 1013 { 1014 size_t i; 1015 uint32_t crc; 1016 int bit; 1017 uint8_t data; 1018 1019 crc = 0xffffffff; /* initial value */ 1020 1021 for (i = 0; i < len; i++) { 1022 for (data = *buf++, bit = 0; bit < 8; bit++, data >>= 1) { 1023 carry = (crc ^ data) & 1; 1024 crc >>= 1; 1025 if (carry) 1026 crc = (crc ^ ETHER_CRC_POLY_LE); 1027 } 1028 } 1029 1030 return (crc); 1031 } 1032 #else 1033 uint32_t 1034 ether_crc32_le(const uint8_t *buf, size_t len) 1035 { 1036 static const uint32_t crctab[] = { 1037 0x00000000, 0x1db71064, 0x3b6e20c8, 0x26d930ac, 1038 0x76dc4190, 0x6b6b51f4, 0x4db26158, 0x5005713c, 1039 0xedb88320, 0xf00f9344, 0xd6d6a3e8, 0xcb61b38c, 1040 0x9b64c2b0, 0x86d3d2d4, 0xa00ae278, 0xbdbdf21c 1041 }; 1042 size_t i; 1043 uint32_t crc; 1044 1045 crc = 0xffffffff; /* initial value */ 1046 1047 for (i = 0; i < len; i++) { 1048 crc ^= buf[i]; 1049 crc = (crc >> 4) ^ crctab[crc & 0xf]; 1050 crc = (crc >> 4) ^ crctab[crc & 0xf]; 1051 } 1052 1053 return (crc); 1054 } 1055 #endif 1056 1057 uint32_t 1058 ether_crc32_be(const uint8_t *buf, size_t len) 1059 { 1060 size_t i; 1061 uint32_t crc, carry; 1062 int bit; 1063 uint8_t data; 1064 1065 crc = 0xffffffff; /* initial value */ 1066 1067 for (i = 0; i < len; i++) { 1068 for (data = *buf++, bit = 0; bit < 8; bit++, data >>= 1) { 1069 carry = ((crc & 0x80000000) ? 1 : 0) ^ (data & 0x01); 1070 crc <<= 1; 1071 if (carry) 1072 crc = (crc ^ ETHER_CRC_POLY_BE) | carry; 1073 } 1074 } 1075 1076 return (crc); 1077 } 1078 1079 int 1080 ether_ioctl(struct ifnet *ifp, u_long command, caddr_t data) 1081 { 1082 struct ifaddr *ifa = (struct ifaddr *) data; 1083 struct ifreq *ifr = (struct ifreq *) data; 1084 int error = 0; 1085 1086 switch (command) { 1087 case SIOCSIFADDR: 1088 ifp->if_flags |= IFF_UP; 1089 1090 switch (ifa->ifa_addr->sa_family) { 1091 #ifdef INET 1092 case AF_INET: 1093 ifp->if_init(ifp->if_softc); /* before arpwhohas */ 1094 arp_ifinit(ifp, ifa); 1095 break; 1096 #endif 1097 #ifdef IPX 1098 /* 1099 * XXX - This code is probably wrong 1100 */ 1101 case AF_IPX: 1102 { 1103 struct ipx_addr *ina = &(IA_SIPX(ifa)->sipx_addr); 1104 1105 if (ipx_nullhost(*ina)) 1106 ina->x_host = 1107 *(union ipx_host *) 1108 IF_LLADDR(ifp); 1109 else { 1110 bcopy((caddr_t) ina->x_host.c_host, 1111 (caddr_t) IF_LLADDR(ifp), 1112 ETHER_ADDR_LEN); 1113 } 1114 1115 /* 1116 * Set new address 1117 */ 1118 ifp->if_init(ifp->if_softc); 1119 break; 1120 } 1121 #endif 1122 default: 1123 ifp->if_init(ifp->if_softc); 1124 break; 1125 } 1126 break; 1127 1128 case SIOCGIFADDR: 1129 { 1130 struct sockaddr *sa; 1131 1132 sa = (struct sockaddr *) & ifr->ifr_data; 1133 bcopy(IF_LLADDR(ifp), 1134 (caddr_t) sa->sa_data, ETHER_ADDR_LEN); 1135 } 1136 break; 1137 1138 case SIOCSIFMTU: 1139 /* 1140 * Set the interface MTU. 1141 */ 1142 if (ifr->ifr_mtu > ETHERMTU) { 1143 error = EINVAL; 1144 } else { 1145 ifp->if_mtu = ifr->ifr_mtu; 1146 } 1147 break; 1148 default: 1149 error = EINVAL; /* XXX netbsd has ENOTTY??? */ 1150 break; 1151 } 1152 return (error); 1153 } 1154 1155 static int 1156 ether_resolvemulti(struct ifnet *ifp, struct sockaddr **llsa, 1157 struct sockaddr *sa) 1158 { 1159 struct sockaddr_dl *sdl; 1160 #ifdef INET 1161 struct sockaddr_in *sin; 1162 #endif 1163 #ifdef INET6 1164 struct sockaddr_in6 *sin6; 1165 #endif 1166 u_char *e_addr; 1167 1168 switch(sa->sa_family) { 1169 case AF_LINK: 1170 /* 1171 * No mapping needed. Just check that it's a valid MC address. 1172 */ 1173 sdl = (struct sockaddr_dl *)sa; 1174 e_addr = LLADDR(sdl); 1175 if (!ETHER_IS_MULTICAST(e_addr)) 1176 return EADDRNOTAVAIL; 1177 *llsa = 0; 1178 return 0; 1179 1180 #ifdef INET 1181 case AF_INET: 1182 sin = (struct sockaddr_in *)sa; 1183 if (!IN_MULTICAST(ntohl(sin->sin_addr.s_addr))) 1184 return EADDRNOTAVAIL; 1185 sdl = malloc(sizeof *sdl, M_IFMADDR, 1186 M_NOWAIT|M_ZERO); 1187 if (sdl == NULL) 1188 return ENOMEM; 1189 sdl->sdl_len = sizeof *sdl; 1190 sdl->sdl_family = AF_LINK; 1191 sdl->sdl_index = ifp->if_index; 1192 sdl->sdl_type = IFT_ETHER; 1193 sdl->sdl_alen = ETHER_ADDR_LEN; 1194 e_addr = LLADDR(sdl); 1195 ETHER_MAP_IP_MULTICAST(&sin->sin_addr, e_addr); 1196 *llsa = (struct sockaddr *)sdl; 1197 return 0; 1198 #endif 1199 #ifdef INET6 1200 case AF_INET6: 1201 sin6 = (struct sockaddr_in6 *)sa; 1202 if (IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr)) { 1203 /* 1204 * An IP6 address of 0 means listen to all 1205 * of the Ethernet multicast address used for IP6. 1206 * (This is used for multicast routers.) 1207 */ 1208 ifp->if_flags |= IFF_ALLMULTI; 1209 *llsa = 0; 1210 return 0; 1211 } 1212 if (!IN6_IS_ADDR_MULTICAST(&sin6->sin6_addr)) 1213 return EADDRNOTAVAIL; 1214 sdl = malloc(sizeof *sdl, M_IFMADDR, 1215 M_NOWAIT|M_ZERO); 1216 if (sdl == NULL) 1217 return (ENOMEM); 1218 sdl->sdl_len = sizeof *sdl; 1219 sdl->sdl_family = AF_LINK; 1220 sdl->sdl_index = ifp->if_index; 1221 sdl->sdl_type = IFT_ETHER; 1222 sdl->sdl_alen = ETHER_ADDR_LEN; 1223 e_addr = LLADDR(sdl); 1224 ETHER_MAP_IPV6_MULTICAST(&sin6->sin6_addr, e_addr); 1225 *llsa = (struct sockaddr *)sdl; 1226 return 0; 1227 #endif 1228 1229 default: 1230 /* 1231 * Well, the text isn't quite right, but it's the name 1232 * that counts... 1233 */ 1234 return EAFNOSUPPORT; 1235 } 1236 } 1237 1238 static void* 1239 ether_alloc(u_char type, struct ifnet *ifp) 1240 { 1241 struct arpcom *ac; 1242 1243 ac = malloc(sizeof(struct arpcom), M_ARPCOM, M_WAITOK | M_ZERO); 1244 ac->ac_ifp = ifp; 1245 1246 return (ac); 1247 } 1248 1249 static void 1250 ether_free(void *com, u_char type) 1251 { 1252 1253 free(com, M_ARPCOM); 1254 } 1255 1256 static int 1257 ether_modevent(module_t mod, int type, void *data) 1258 { 1259 1260 switch (type) { 1261 case MOD_LOAD: 1262 if_register_com_alloc(IFT_ETHER, ether_alloc, ether_free); 1263 break; 1264 case MOD_UNLOAD: 1265 if_deregister_com_alloc(IFT_ETHER); 1266 break; 1267 default: 1268 return EOPNOTSUPP; 1269 } 1270 1271 return (0); 1272 } 1273 1274 static moduledata_t ether_mod = { 1275 "ether", 1276 ether_modevent, 1277 0 1278 }; 1279 1280 void 1281 ether_vlan_mtap(struct bpf_if *bp, struct mbuf *m, void *data, u_int dlen) 1282 { 1283 struct ether_vlan_header vlan; 1284 struct mbuf mv, mb; 1285 1286 KASSERT((m->m_flags & M_VLANTAG) != 0, 1287 ("%s: vlan information not present", __func__)); 1288 KASSERT(m->m_len >= sizeof(struct ether_header), 1289 ("%s: mbuf not large enough for header", __func__)); 1290 bcopy(mtod(m, char *), &vlan, sizeof(struct ether_header)); 1291 vlan.evl_proto = vlan.evl_encap_proto; 1292 vlan.evl_encap_proto = htons(ETHERTYPE_VLAN); 1293 vlan.evl_tag = htons(m->m_pkthdr.ether_vtag); 1294 m->m_len -= sizeof(struct ether_header); 1295 m->m_data += sizeof(struct ether_header); 1296 /* 1297 * If a data link has been supplied by the caller, then we will need to 1298 * re-create a stack allocated mbuf chain with the following structure: 1299 * 1300 * (1) mbuf #1 will contain the supplied data link 1301 * (2) mbuf #2 will contain the vlan header 1302 * (3) mbuf #3 will contain the original mbuf's packet data 1303 * 1304 * Otherwise, submit the packet and vlan header via bpf_mtap2(). 1305 */ 1306 if (data != NULL) { 1307 mv.m_next = m; 1308 mv.m_data = (caddr_t)&vlan; 1309 mv.m_len = sizeof(vlan); 1310 mb.m_next = &mv; 1311 mb.m_data = data; 1312 mb.m_len = dlen; 1313 bpf_mtap(bp, &mb); 1314 } else 1315 bpf_mtap2(bp, &vlan, sizeof(vlan), m); 1316 m->m_len += sizeof(struct ether_header); 1317 m->m_data -= sizeof(struct ether_header); 1318 } 1319 1320 struct mbuf * 1321 ether_vlanencap(struct mbuf *m, uint16_t tag) 1322 { 1323 struct ether_vlan_header *evl; 1324 1325 M_PREPEND(m, ETHER_VLAN_ENCAP_LEN, M_DONTWAIT); 1326 if (m == NULL) 1327 return (NULL); 1328 /* M_PREPEND takes care of m_len, m_pkthdr.len for us */ 1329 1330 if (m->m_len < sizeof(*evl)) { 1331 m = m_pullup(m, sizeof(*evl)); 1332 if (m == NULL) 1333 return (NULL); 1334 } 1335 1336 /* 1337 * Transform the Ethernet header into an Ethernet header 1338 * with 802.1Q encapsulation. 1339 */ 1340 evl = mtod(m, struct ether_vlan_header *); 1341 bcopy((char *)evl + ETHER_VLAN_ENCAP_LEN, 1342 (char *)evl, ETHER_HDR_LEN - ETHER_TYPE_LEN); 1343 evl->evl_encap_proto = htons(ETHERTYPE_VLAN); 1344 evl->evl_tag = htons(tag); 1345 return (m); 1346 } 1347 1348 DECLARE_MODULE(ether, ether_mod, SI_SUB_INIT_IF, SI_ORDER_ANY); 1349 MODULE_VERSION(ether, 1); 1350