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_mbuf_profiling.h" 39 40 #include <sys/param.h> 41 #include <sys/systm.h> 42 #include <sys/kernel.h> 43 #include <sys/lock.h> 44 #include <sys/malloc.h> 45 #include <sys/module.h> 46 #include <sys/mbuf.h> 47 #include <sys/random.h> 48 #include <sys/rwlock.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 #include <net/if_llatbl.h> 65 #include <net/pf_mtag.h> 66 #include <net/vnet.h> 67 68 #if defined(INET) || defined(INET6) 69 #include <netinet/in.h> 70 #include <netinet/in_var.h> 71 #include <netinet/if_ether.h> 72 #include <netinet/ip_carp.h> 73 #include <netinet/ip_var.h> 74 #include <netinet/ip_fw.h> 75 #include <netinet/ipfw/ip_fw_private.h> 76 #endif 77 #ifdef INET6 78 #include <netinet6/nd6.h> 79 #endif 80 81 #ifdef IPX 82 #include <netipx/ipx.h> 83 #include <netipx/ipx_if.h> 84 #endif 85 86 int (*ef_inputp)(struct ifnet*, struct ether_header *eh, struct mbuf *m); 87 int (*ef_outputp)(struct ifnet *ifp, struct mbuf **mp, 88 struct sockaddr *dst, short *tp, int *hlen); 89 90 #ifdef NETATALK 91 #include <netatalk/at.h> 92 #include <netatalk/at_var.h> 93 #include <netatalk/at_extern.h> 94 95 #define llc_snap_org_code llc_un.type_snap.org_code 96 #define llc_snap_ether_type llc_un.type_snap.ether_type 97 98 extern u_char at_org_code[3]; 99 extern u_char aarp_org_code[3]; 100 #endif /* NETATALK */ 101 102 #include <security/mac/mac_framework.h> 103 104 #ifdef CTASSERT 105 CTASSERT(sizeof (struct ether_header) == ETHER_ADDR_LEN * 2 + 2); 106 CTASSERT(sizeof (struct ether_addr) == ETHER_ADDR_LEN); 107 #endif 108 109 /* netgraph node hooks for ng_ether(4) */ 110 void (*ng_ether_input_p)(struct ifnet *ifp, struct mbuf **mp); 111 void (*ng_ether_input_orphan_p)(struct ifnet *ifp, struct mbuf *m); 112 int (*ng_ether_output_p)(struct ifnet *ifp, struct mbuf **mp); 113 void (*ng_ether_attach_p)(struct ifnet *ifp); 114 void (*ng_ether_detach_p)(struct ifnet *ifp); 115 116 void (*vlan_input_p)(struct ifnet *, struct mbuf *); 117 118 /* if_bridge(4) support */ 119 struct mbuf *(*bridge_input_p)(struct ifnet *, struct mbuf *); 120 int (*bridge_output_p)(struct ifnet *, struct mbuf *, 121 struct sockaddr *, struct rtentry *); 122 void (*bridge_dn_p)(struct mbuf *, struct ifnet *); 123 124 /* if_lagg(4) support */ 125 struct mbuf *(*lagg_input_p)(struct ifnet *, struct mbuf *); 126 127 static const u_char etherbroadcastaddr[ETHER_ADDR_LEN] = 128 { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff }; 129 130 static int ether_resolvemulti(struct ifnet *, struct sockaddr **, 131 struct sockaddr *); 132 #ifdef VIMAGE 133 static void ether_reassign(struct ifnet *, struct vnet *, char *); 134 #endif 135 136 /* XXX: should be in an arp support file, not here */ 137 MALLOC_DEFINE(M_ARPCOM, "arpcom", "802.* interface internals"); 138 139 #define ETHER_IS_BROADCAST(addr) \ 140 (bcmp(etherbroadcastaddr, (addr), ETHER_ADDR_LEN) == 0) 141 142 #define senderr(e) do { error = (e); goto bad;} while (0) 143 144 #if defined(INET) || defined(INET6) 145 int 146 ether_ipfw_chk(struct mbuf **m0, struct ifnet *dst, int shared); 147 static VNET_DEFINE(int, ether_ipfw); 148 #define V_ether_ipfw VNET(ether_ipfw) 149 #endif 150 151 152 /* 153 * Ethernet output routine. 154 * Encapsulate a packet of type family for the local net. 155 * Use trailer local net encapsulation if enough data in first 156 * packet leaves a multiple of 512 bytes of data in remainder. 157 */ 158 int 159 ether_output(struct ifnet *ifp, struct mbuf *m, 160 struct sockaddr *dst, struct route *ro) 161 { 162 short type; 163 int error = 0, hdrcmplt = 0; 164 u_char esrc[ETHER_ADDR_LEN], edst[ETHER_ADDR_LEN]; 165 struct llentry *lle = NULL; 166 struct rtentry *rt0 = NULL; 167 struct ether_header *eh; 168 struct pf_mtag *t; 169 int loop_copy = 1; 170 int hlen; /* link layer header length */ 171 172 if (ro != NULL) { 173 if (!(m->m_flags & (M_BCAST | M_MCAST))) 174 lle = ro->ro_lle; 175 rt0 = ro->ro_rt; 176 } 177 #ifdef MAC 178 error = mac_ifnet_check_transmit(ifp, m); 179 if (error) 180 senderr(error); 181 #endif 182 183 M_PROFILE(m); 184 if (ifp->if_flags & IFF_MONITOR) 185 senderr(ENETDOWN); 186 if (!((ifp->if_flags & IFF_UP) && 187 (ifp->if_drv_flags & IFF_DRV_RUNNING))) 188 senderr(ENETDOWN); 189 190 hlen = ETHER_HDR_LEN; 191 switch (dst->sa_family) { 192 #ifdef INET 193 case AF_INET: 194 if (lle != NULL && (lle->la_flags & LLE_VALID)) 195 memcpy(edst, &lle->ll_addr.mac16, sizeof(edst)); 196 else 197 error = arpresolve(ifp, rt0, m, dst, edst, &lle); 198 if (error) 199 return (error == EWOULDBLOCK ? 0 : error); 200 type = htons(ETHERTYPE_IP); 201 break; 202 case AF_ARP: 203 { 204 struct arphdr *ah; 205 ah = mtod(m, struct arphdr *); 206 ah->ar_hrd = htons(ARPHRD_ETHER); 207 208 loop_copy = 0; /* if this is for us, don't do it */ 209 210 switch(ntohs(ah->ar_op)) { 211 case ARPOP_REVREQUEST: 212 case ARPOP_REVREPLY: 213 type = htons(ETHERTYPE_REVARP); 214 break; 215 case ARPOP_REQUEST: 216 case ARPOP_REPLY: 217 default: 218 type = htons(ETHERTYPE_ARP); 219 break; 220 } 221 222 if (m->m_flags & M_BCAST) 223 bcopy(ifp->if_broadcastaddr, edst, ETHER_ADDR_LEN); 224 else 225 bcopy(ar_tha(ah), edst, ETHER_ADDR_LEN); 226 227 } 228 break; 229 #endif 230 #ifdef INET6 231 case AF_INET6: 232 if (lle != NULL && (lle->la_flags & LLE_VALID)) 233 memcpy(edst, &lle->ll_addr.mac16, sizeof(edst)); 234 else 235 error = nd6_storelladdr(ifp, m, dst, (u_char *)edst, &lle); 236 if (error) 237 return error; 238 type = htons(ETHERTYPE_IPV6); 239 break; 240 #endif 241 #ifdef IPX 242 case AF_IPX: 243 if (ef_outputp) { 244 error = ef_outputp(ifp, &m, dst, &type, &hlen); 245 if (error) 246 goto bad; 247 } else 248 type = htons(ETHERTYPE_IPX); 249 bcopy((caddr_t)&(((struct sockaddr_ipx *)dst)->sipx_addr.x_host), 250 (caddr_t)edst, sizeof (edst)); 251 break; 252 #endif 253 #ifdef NETATALK 254 case AF_APPLETALK: 255 { 256 struct at_ifaddr *aa; 257 258 if ((aa = at_ifawithnet((struct sockaddr_at *)dst)) == NULL) 259 senderr(EHOSTUNREACH); /* XXX */ 260 if (!aarpresolve(ifp, m, (struct sockaddr_at *)dst, edst)) { 261 ifa_free(&aa->aa_ifa); 262 return (0); 263 } 264 /* 265 * In the phase 2 case, need to prepend an mbuf for the llc header. 266 */ 267 if ( aa->aa_flags & AFA_PHASE2 ) { 268 struct llc llc; 269 270 ifa_free(&aa->aa_ifa); 271 M_PREPEND(m, LLC_SNAPFRAMELEN, M_DONTWAIT); 272 if (m == NULL) 273 senderr(ENOBUFS); 274 llc.llc_dsap = llc.llc_ssap = LLC_SNAP_LSAP; 275 llc.llc_control = LLC_UI; 276 bcopy(at_org_code, llc.llc_snap_org_code, sizeof(at_org_code)); 277 llc.llc_snap_ether_type = htons( ETHERTYPE_AT ); 278 bcopy(&llc, mtod(m, caddr_t), LLC_SNAPFRAMELEN); 279 type = htons(m->m_pkthdr.len); 280 hlen = LLC_SNAPFRAMELEN + ETHER_HDR_LEN; 281 } else { 282 ifa_free(&aa->aa_ifa); 283 type = htons(ETHERTYPE_AT); 284 } 285 break; 286 } 287 #endif /* NETATALK */ 288 289 case pseudo_AF_HDRCMPLT: 290 hdrcmplt = 1; 291 eh = (struct ether_header *)dst->sa_data; 292 (void)memcpy(esrc, eh->ether_shost, sizeof (esrc)); 293 /* FALLTHROUGH */ 294 295 case AF_UNSPEC: 296 loop_copy = 0; /* if this is for us, don't do it */ 297 eh = (struct ether_header *)dst->sa_data; 298 (void)memcpy(edst, eh->ether_dhost, sizeof (edst)); 299 type = eh->ether_type; 300 break; 301 302 default: 303 if_printf(ifp, "can't handle af%d\n", dst->sa_family); 304 senderr(EAFNOSUPPORT); 305 } 306 307 if (lle != NULL && (lle->la_flags & LLE_IFADDR)) { 308 int csum_flags = 0; 309 if (m->m_pkthdr.csum_flags & CSUM_IP) 310 csum_flags |= (CSUM_IP_CHECKED|CSUM_IP_VALID); 311 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) 312 csum_flags |= (CSUM_DATA_VALID|CSUM_PSEUDO_HDR); 313 if (m->m_pkthdr.csum_flags & CSUM_SCTP) 314 csum_flags |= CSUM_SCTP_VALID; 315 m->m_pkthdr.csum_flags |= csum_flags; 316 m->m_pkthdr.csum_data = 0xffff; 317 return (if_simloop(ifp, m, dst->sa_family, 0)); 318 } 319 320 /* 321 * Add local net header. If no space in first mbuf, 322 * allocate another. 323 */ 324 M_PREPEND(m, ETHER_HDR_LEN, M_DONTWAIT); 325 if (m == NULL) 326 senderr(ENOBUFS); 327 eh = mtod(m, struct ether_header *); 328 (void)memcpy(&eh->ether_type, &type, 329 sizeof(eh->ether_type)); 330 (void)memcpy(eh->ether_dhost, edst, sizeof (edst)); 331 if (hdrcmplt) 332 (void)memcpy(eh->ether_shost, esrc, 333 sizeof(eh->ether_shost)); 334 else 335 (void)memcpy(eh->ether_shost, IF_LLADDR(ifp), 336 sizeof(eh->ether_shost)); 337 338 /* 339 * If a simplex interface, and the packet is being sent to our 340 * Ethernet address or a broadcast address, loopback a copy. 341 * XXX To make a simplex device behave exactly like a duplex 342 * device, we should copy in the case of sending to our own 343 * ethernet address (thus letting the original actually appear 344 * on the wire). However, we don't do that here for security 345 * reasons and compatibility with the original behavior. 346 */ 347 if ((ifp->if_flags & IFF_SIMPLEX) && loop_copy && 348 ((t = pf_find_mtag(m)) == NULL || !t->routed)) { 349 int csum_flags = 0; 350 351 if (m->m_pkthdr.csum_flags & CSUM_IP) 352 csum_flags |= (CSUM_IP_CHECKED|CSUM_IP_VALID); 353 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) 354 csum_flags |= (CSUM_DATA_VALID|CSUM_PSEUDO_HDR); 355 if (m->m_pkthdr.csum_flags & CSUM_SCTP) 356 csum_flags |= CSUM_SCTP_VALID; 357 358 if (m->m_flags & M_BCAST) { 359 struct mbuf *n; 360 361 /* 362 * Because if_simloop() modifies the packet, we need a 363 * writable copy through m_dup() instead of a readonly 364 * one as m_copy[m] would give us. The alternative would 365 * be to modify if_simloop() to handle the readonly mbuf, 366 * but performancewise it is mostly equivalent (trading 367 * extra data copying vs. extra locking). 368 * 369 * XXX This is a local workaround. A number of less 370 * often used kernel parts suffer from the same bug. 371 * See PR kern/105943 for a proposed general solution. 372 */ 373 if ((n = m_dup(m, M_DONTWAIT)) != NULL) { 374 n->m_pkthdr.csum_flags |= csum_flags; 375 if (csum_flags & CSUM_DATA_VALID) 376 n->m_pkthdr.csum_data = 0xffff; 377 (void)if_simloop(ifp, n, dst->sa_family, hlen); 378 } else 379 ifp->if_iqdrops++; 380 } else if (bcmp(eh->ether_dhost, eh->ether_shost, 381 ETHER_ADDR_LEN) == 0) { 382 m->m_pkthdr.csum_flags |= csum_flags; 383 if (csum_flags & CSUM_DATA_VALID) 384 m->m_pkthdr.csum_data = 0xffff; 385 (void) if_simloop(ifp, m, dst->sa_family, hlen); 386 return (0); /* XXX */ 387 } 388 } 389 390 /* 391 * Bridges require special output handling. 392 */ 393 if (ifp->if_bridge) { 394 BRIDGE_OUTPUT(ifp, m, error); 395 return (error); 396 } 397 398 #if defined(INET) || defined(INET6) 399 if (ifp->if_carp && 400 (error = (*carp_output_p)(ifp, m, dst, NULL))) 401 goto bad; 402 #endif 403 404 /* Handle ng_ether(4) processing, if any */ 405 if (IFP2AC(ifp)->ac_netgraph != NULL) { 406 KASSERT(ng_ether_output_p != NULL, 407 ("ng_ether_output_p is NULL")); 408 if ((error = (*ng_ether_output_p)(ifp, &m)) != 0) { 409 bad: if (m != NULL) 410 m_freem(m); 411 return (error); 412 } 413 if (m == NULL) 414 return (0); 415 } 416 417 /* Continue with link-layer output */ 418 return ether_output_frame(ifp, m); 419 } 420 421 /* 422 * Ethernet link layer output routine to send a raw frame to the device. 423 * 424 * This assumes that the 14 byte Ethernet header is present and contiguous 425 * in the first mbuf (if BRIDGE'ing). 426 */ 427 int 428 ether_output_frame(struct ifnet *ifp, struct mbuf *m) 429 { 430 #if defined(INET) || defined(INET6) 431 432 if (V_ip_fw_chk_ptr && V_ether_ipfw != 0) { 433 if (ether_ipfw_chk(&m, ifp, 0) == 0) { 434 if (m) { 435 m_freem(m); 436 return EACCES; /* pkt dropped */ 437 } else 438 return 0; /* consumed e.g. in a pipe */ 439 } 440 } 441 #endif 442 443 /* 444 * Queue message on interface, update output statistics if 445 * successful, and start output if interface not yet active. 446 */ 447 return ((ifp->if_transmit)(ifp, m)); 448 } 449 450 #if defined(INET) || defined(INET6) 451 /* 452 * ipfw processing for ethernet packets (in and out). 453 * The second parameter is NULL from ether_demux, and ifp from 454 * ether_output_frame. 455 */ 456 int 457 ether_ipfw_chk(struct mbuf **m0, struct ifnet *dst, int shared) 458 { 459 struct ether_header *eh; 460 struct ether_header save_eh; 461 struct mbuf *m; 462 int i; 463 struct ip_fw_args args; 464 struct m_tag *mtag; 465 466 /* fetch start point from rule, if any */ 467 mtag = m_tag_locate(*m0, MTAG_IPFW_RULE, 0, NULL); 468 if (mtag == NULL) { 469 args.rule.slot = 0; 470 } else { 471 /* dummynet packet, already partially processed */ 472 struct ipfw_rule_ref *r; 473 474 /* XXX can we free it after use ? */ 475 mtag->m_tag_id = PACKET_TAG_NONE; 476 r = (struct ipfw_rule_ref *)(mtag + 1); 477 if (r->info & IPFW_ONEPASS) 478 return (1); 479 args.rule = *r; 480 } 481 482 /* 483 * I need some amt of data to be contiguous, and in case others need 484 * the packet (shared==1) also better be in the first mbuf. 485 */ 486 m = *m0; 487 i = min( m->m_pkthdr.len, max_protohdr); 488 if ( shared || m->m_len < i) { 489 m = m_pullup(m, i); 490 if (m == NULL) { 491 *m0 = m; 492 return 0; 493 } 494 } 495 eh = mtod(m, struct ether_header *); 496 save_eh = *eh; /* save copy for restore below */ 497 m_adj(m, ETHER_HDR_LEN); /* strip ethernet header */ 498 499 args.m = m; /* the packet we are looking at */ 500 args.oif = dst; /* destination, if any */ 501 args.next_hop = NULL; /* we do not support forward yet */ 502 args.eh = &save_eh; /* MAC header for bridged/MAC packets */ 503 args.inp = NULL; /* used by ipfw uid/gid/jail rules */ 504 i = V_ip_fw_chk_ptr(&args); 505 m = args.m; 506 if (m != NULL) { 507 /* 508 * Restore Ethernet header, as needed, in case the 509 * mbuf chain was replaced by ipfw. 510 */ 511 M_PREPEND(m, ETHER_HDR_LEN, M_DONTWAIT); 512 if (m == NULL) { 513 *m0 = m; 514 return 0; 515 } 516 if (eh != mtod(m, struct ether_header *)) 517 bcopy(&save_eh, mtod(m, struct ether_header *), 518 ETHER_HDR_LEN); 519 } 520 *m0 = m; 521 522 if (i == IP_FW_DENY) /* drop */ 523 return 0; 524 525 KASSERT(m != NULL, ("ether_ipfw_chk: m is NULL")); 526 527 if (i == IP_FW_PASS) /* a PASS rule. */ 528 return 1; 529 530 if (ip_dn_io_ptr && (i == IP_FW_DUMMYNET)) { 531 int dir; 532 /* 533 * Pass the pkt to dummynet, which consumes it. 534 * If shared, make a copy and keep the original. 535 */ 536 if (shared) { 537 m = m_copypacket(m, M_DONTWAIT); 538 if (m == NULL) 539 return 0; 540 } else { 541 /* 542 * Pass the original to dummynet and 543 * nothing back to the caller 544 */ 545 *m0 = NULL ; 546 } 547 dir = PROTO_LAYER2 | (dst ? DIR_OUT : DIR_IN); 548 ip_dn_io_ptr(&m, dir, &args); 549 return 0; 550 } 551 /* 552 * XXX at some point add support for divert/forward actions. 553 * If none of the above matches, we have to drop the pkt. 554 */ 555 return 0; 556 } 557 #endif 558 559 /* 560 * Process a received Ethernet packet; the packet is in the 561 * mbuf chain m with the ethernet header at the front. 562 */ 563 static void 564 ether_input(struct ifnet *ifp, struct mbuf *m) 565 { 566 struct ether_header *eh; 567 u_short etype; 568 569 if ((ifp->if_flags & IFF_UP) == 0) { 570 m_freem(m); 571 return; 572 } 573 #ifdef DIAGNOSTIC 574 if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0) { 575 if_printf(ifp, "discard frame at !IFF_DRV_RUNNING\n"); 576 m_freem(m); 577 return; 578 } 579 #endif 580 /* 581 * Do consistency checks to verify assumptions 582 * made by code past this point. 583 */ 584 if ((m->m_flags & M_PKTHDR) == 0) { 585 if_printf(ifp, "discard frame w/o packet header\n"); 586 ifp->if_ierrors++; 587 m_freem(m); 588 return; 589 } 590 if (m->m_len < ETHER_HDR_LEN) { 591 /* XXX maybe should pullup? */ 592 if_printf(ifp, "discard frame w/o leading ethernet " 593 "header (len %u pkt len %u)\n", 594 m->m_len, m->m_pkthdr.len); 595 ifp->if_ierrors++; 596 m_freem(m); 597 return; 598 } 599 eh = mtod(m, struct ether_header *); 600 etype = ntohs(eh->ether_type); 601 if (m->m_pkthdr.rcvif == NULL) { 602 if_printf(ifp, "discard frame w/o interface pointer\n"); 603 ifp->if_ierrors++; 604 m_freem(m); 605 return; 606 } 607 #ifdef DIAGNOSTIC 608 if (m->m_pkthdr.rcvif != ifp) { 609 if_printf(ifp, "Warning, frame marked as received on %s\n", 610 m->m_pkthdr.rcvif->if_xname); 611 } 612 #endif 613 614 CURVNET_SET_QUIET(ifp->if_vnet); 615 616 if (ETHER_IS_MULTICAST(eh->ether_dhost)) { 617 if (ETHER_IS_BROADCAST(eh->ether_dhost)) 618 m->m_flags |= M_BCAST; 619 else 620 m->m_flags |= M_MCAST; 621 ifp->if_imcasts++; 622 } 623 624 #ifdef MAC 625 /* 626 * Tag the mbuf with an appropriate MAC label before any other 627 * consumers can get to it. 628 */ 629 mac_ifnet_create_mbuf(ifp, m); 630 #endif 631 632 /* 633 * Give bpf a chance at the packet. 634 */ 635 ETHER_BPF_MTAP(ifp, m); 636 637 /* 638 * If the CRC is still on the packet, trim it off. We do this once 639 * and once only in case we are re-entered. Nothing else on the 640 * Ethernet receive path expects to see the FCS. 641 */ 642 if (m->m_flags & M_HASFCS) { 643 m_adj(m, -ETHER_CRC_LEN); 644 m->m_flags &= ~M_HASFCS; 645 } 646 647 ifp->if_ibytes += m->m_pkthdr.len; 648 649 /* Allow monitor mode to claim this frame, after stats are updated. */ 650 if (ifp->if_flags & IFF_MONITOR) { 651 m_freem(m); 652 CURVNET_RESTORE(); 653 return; 654 } 655 656 /* Handle input from a lagg(4) port */ 657 if (ifp->if_type == IFT_IEEE8023ADLAG) { 658 KASSERT(lagg_input_p != NULL, 659 ("%s: if_lagg not loaded!", __func__)); 660 m = (*lagg_input_p)(ifp, m); 661 if (m != NULL) 662 ifp = m->m_pkthdr.rcvif; 663 else 664 return; 665 } 666 667 /* 668 * If the hardware did not process an 802.1Q tag, do this now, 669 * to allow 802.1P priority frames to be passed to the main input 670 * path correctly. 671 * TODO: Deal with Q-in-Q frames, but not arbitrary nesting levels. 672 */ 673 if ((m->m_flags & M_VLANTAG) == 0 && etype == ETHERTYPE_VLAN) { 674 struct ether_vlan_header *evl; 675 676 if (m->m_len < sizeof(*evl) && 677 (m = m_pullup(m, sizeof(*evl))) == NULL) { 678 #ifdef DIAGNOSTIC 679 if_printf(ifp, "cannot pullup VLAN header\n"); 680 #endif 681 ifp->if_ierrors++; 682 m_freem(m); 683 return; 684 } 685 686 evl = mtod(m, struct ether_vlan_header *); 687 m->m_pkthdr.ether_vtag = ntohs(evl->evl_tag); 688 m->m_flags |= M_VLANTAG; 689 690 bcopy((char *)evl, (char *)evl + ETHER_VLAN_ENCAP_LEN, 691 ETHER_HDR_LEN - ETHER_TYPE_LEN); 692 m_adj(m, ETHER_VLAN_ENCAP_LEN); 693 } 694 695 /* Allow ng_ether(4) to claim this frame. */ 696 if (IFP2AC(ifp)->ac_netgraph != NULL) { 697 KASSERT(ng_ether_input_p != NULL, 698 ("%s: ng_ether_input_p is NULL", __func__)); 699 m->m_flags &= ~M_PROMISC; 700 (*ng_ether_input_p)(ifp, &m); 701 if (m == NULL) { 702 CURVNET_RESTORE(); 703 return; 704 } 705 } 706 707 /* 708 * Allow if_bridge(4) to claim this frame. 709 * The BRIDGE_INPUT() macro will update ifp if the bridge changed it 710 * and the frame should be delivered locally. 711 */ 712 if (ifp->if_bridge != NULL) { 713 m->m_flags &= ~M_PROMISC; 714 BRIDGE_INPUT(ifp, m); 715 if (m == NULL) { 716 CURVNET_RESTORE(); 717 return; 718 } 719 } 720 721 #if defined(INET) || defined(INET6) 722 /* 723 * Clear M_PROMISC on frame so that carp(4) will see it when the 724 * mbuf flows up to Layer 3. 725 * FreeBSD's implementation of carp(4) uses the inprotosw 726 * to dispatch IPPROTO_CARP. carp(4) also allocates its own 727 * Ethernet addresses of the form 00:00:5e:00:01:xx, which 728 * is outside the scope of the M_PROMISC test below. 729 * TODO: Maintain a hash table of ethernet addresses other than 730 * ether_dhost which may be active on this ifp. 731 */ 732 if (ifp->if_carp && (*carp_forus_p)(ifp, eh->ether_dhost)) { 733 m->m_flags &= ~M_PROMISC; 734 } else 735 #endif 736 { 737 /* 738 * If the frame received was not for our MAC address, set the 739 * M_PROMISC flag on the mbuf chain. The frame may need to 740 * be seen by the rest of the Ethernet input path in case of 741 * re-entry (e.g. bridge, vlan, netgraph) but should not be 742 * seen by upper protocol layers. 743 */ 744 if (!ETHER_IS_MULTICAST(eh->ether_dhost) && 745 bcmp(IF_LLADDR(ifp), eh->ether_dhost, ETHER_ADDR_LEN) != 0) 746 m->m_flags |= M_PROMISC; 747 } 748 749 /* First chunk of an mbuf contains good entropy */ 750 if (harvest.ethernet) 751 random_harvest(m, 16, 3, 0, RANDOM_NET); 752 753 ether_demux(ifp, m); 754 CURVNET_RESTORE(); 755 } 756 757 /* 758 * Upper layer processing for a received Ethernet packet. 759 */ 760 void 761 ether_demux(struct ifnet *ifp, struct mbuf *m) 762 { 763 struct ether_header *eh; 764 int isr; 765 u_short ether_type; 766 #if defined(NETATALK) 767 struct llc *l; 768 #endif 769 770 KASSERT(ifp != NULL, ("%s: NULL interface pointer", __func__)); 771 772 #if defined(INET) || defined(INET6) 773 /* 774 * Allow dummynet and/or ipfw to claim the frame. 775 * Do not do this for PROMISC frames in case we are re-entered. 776 */ 777 if (V_ip_fw_chk_ptr && V_ether_ipfw != 0 && !(m->m_flags & M_PROMISC)) { 778 if (ether_ipfw_chk(&m, NULL, 0) == 0) { 779 if (m) 780 m_freem(m); /* dropped; free mbuf chain */ 781 return; /* consumed */ 782 } 783 } 784 #endif 785 eh = mtod(m, struct ether_header *); 786 ether_type = ntohs(eh->ether_type); 787 788 /* 789 * If this frame has a VLAN tag other than 0, call vlan_input() 790 * if its module is loaded. Otherwise, drop. 791 */ 792 if ((m->m_flags & M_VLANTAG) && 793 EVL_VLANOFTAG(m->m_pkthdr.ether_vtag) != 0) { 794 if (ifp->if_vlantrunk == NULL) { 795 ifp->if_noproto++; 796 m_freem(m); 797 return; 798 } 799 KASSERT(vlan_input_p != NULL,("%s: VLAN not loaded!", 800 __func__)); 801 /* Clear before possibly re-entering ether_input(). */ 802 m->m_flags &= ~M_PROMISC; 803 (*vlan_input_p)(ifp, m); 804 return; 805 } 806 807 /* 808 * Pass promiscuously received frames to the upper layer if the user 809 * requested this by setting IFF_PPROMISC. Otherwise, drop them. 810 */ 811 if ((ifp->if_flags & IFF_PPROMISC) == 0 && (m->m_flags & M_PROMISC)) { 812 m_freem(m); 813 return; 814 } 815 816 /* 817 * Reset layer specific mbuf flags to avoid confusing upper layers. 818 * Strip off Ethernet header. 819 */ 820 m->m_flags &= ~M_VLANTAG; 821 m->m_flags &= ~(M_PROTOFLAGS); 822 m_adj(m, ETHER_HDR_LEN); 823 824 /* 825 * Dispatch frame to upper layer. 826 */ 827 switch (ether_type) { 828 #ifdef INET 829 case ETHERTYPE_IP: 830 if ((m = ip_fastforward(m)) == NULL) 831 return; 832 isr = NETISR_IP; 833 break; 834 835 case ETHERTYPE_ARP: 836 if (ifp->if_flags & IFF_NOARP) { 837 /* Discard packet if ARP is disabled on interface */ 838 m_freem(m); 839 return; 840 } 841 isr = NETISR_ARP; 842 break; 843 #endif 844 #ifdef IPX 845 case ETHERTYPE_IPX: 846 if (ef_inputp && ef_inputp(ifp, eh, m) == 0) 847 return; 848 isr = NETISR_IPX; 849 break; 850 #endif 851 #ifdef INET6 852 case ETHERTYPE_IPV6: 853 isr = NETISR_IPV6; 854 break; 855 #endif 856 #ifdef NETATALK 857 case ETHERTYPE_AT: 858 isr = NETISR_ATALK1; 859 break; 860 case ETHERTYPE_AARP: 861 isr = NETISR_AARP; 862 break; 863 #endif /* NETATALK */ 864 default: 865 #ifdef IPX 866 if (ef_inputp && ef_inputp(ifp, eh, m) == 0) 867 return; 868 #endif /* IPX */ 869 #if defined(NETATALK) 870 if (ether_type > ETHERMTU) 871 goto discard; 872 l = mtod(m, struct llc *); 873 if (l->llc_dsap == LLC_SNAP_LSAP && 874 l->llc_ssap == LLC_SNAP_LSAP && 875 l->llc_control == LLC_UI) { 876 if (bcmp(&(l->llc_snap_org_code)[0], at_org_code, 877 sizeof(at_org_code)) == 0 && 878 ntohs(l->llc_snap_ether_type) == ETHERTYPE_AT) { 879 m_adj(m, LLC_SNAPFRAMELEN); 880 isr = NETISR_ATALK2; 881 break; 882 } 883 if (bcmp(&(l->llc_snap_org_code)[0], aarp_org_code, 884 sizeof(aarp_org_code)) == 0 && 885 ntohs(l->llc_snap_ether_type) == ETHERTYPE_AARP) { 886 m_adj(m, LLC_SNAPFRAMELEN); 887 isr = NETISR_AARP; 888 break; 889 } 890 } 891 #endif /* NETATALK */ 892 goto discard; 893 } 894 netisr_dispatch(isr, m); 895 return; 896 897 discard: 898 /* 899 * Packet is to be discarded. If netgraph is present, 900 * hand the packet to it for last chance processing; 901 * otherwise dispose of it. 902 */ 903 if (IFP2AC(ifp)->ac_netgraph != NULL) { 904 KASSERT(ng_ether_input_orphan_p != NULL, 905 ("ng_ether_input_orphan_p is NULL")); 906 /* 907 * Put back the ethernet header so netgraph has a 908 * consistent view of inbound packets. 909 */ 910 M_PREPEND(m, ETHER_HDR_LEN, M_DONTWAIT); 911 (*ng_ether_input_orphan_p)(ifp, m); 912 return; 913 } 914 m_freem(m); 915 } 916 917 /* 918 * Convert Ethernet address to printable (loggable) representation. 919 * This routine is for compatibility; it's better to just use 920 * 921 * printf("%6D", <pointer to address>, ":"); 922 * 923 * since there's no static buffer involved. 924 */ 925 char * 926 ether_sprintf(const u_char *ap) 927 { 928 static char etherbuf[18]; 929 snprintf(etherbuf, sizeof (etherbuf), "%6D", ap, ":"); 930 return (etherbuf); 931 } 932 933 /* 934 * Perform common duties while attaching to interface list 935 */ 936 void 937 ether_ifattach(struct ifnet *ifp, const u_int8_t *lla) 938 { 939 int i; 940 struct ifaddr *ifa; 941 struct sockaddr_dl *sdl; 942 943 ifp->if_addrlen = ETHER_ADDR_LEN; 944 ifp->if_hdrlen = ETHER_HDR_LEN; 945 if_attach(ifp); 946 ifp->if_mtu = ETHERMTU; 947 ifp->if_output = ether_output; 948 ifp->if_input = ether_input; 949 ifp->if_resolvemulti = ether_resolvemulti; 950 #ifdef VIMAGE 951 ifp->if_reassign = ether_reassign; 952 #endif 953 if (ifp->if_baudrate == 0) 954 ifp->if_baudrate = IF_Mbps(10); /* just a default */ 955 ifp->if_broadcastaddr = etherbroadcastaddr; 956 957 ifa = ifp->if_addr; 958 KASSERT(ifa != NULL, ("%s: no lladdr!\n", __func__)); 959 sdl = (struct sockaddr_dl *)ifa->ifa_addr; 960 sdl->sdl_type = IFT_ETHER; 961 sdl->sdl_alen = ifp->if_addrlen; 962 bcopy(lla, LLADDR(sdl), ifp->if_addrlen); 963 964 bpfattach(ifp, DLT_EN10MB, ETHER_HDR_LEN); 965 if (ng_ether_attach_p != NULL) 966 (*ng_ether_attach_p)(ifp); 967 968 /* Announce Ethernet MAC address if non-zero. */ 969 for (i = 0; i < ifp->if_addrlen; i++) 970 if (lla[i] != 0) 971 break; 972 if (i != ifp->if_addrlen) 973 if_printf(ifp, "Ethernet address: %6D\n", lla, ":"); 974 } 975 976 /* 977 * Perform common duties while detaching an Ethernet interface 978 */ 979 void 980 ether_ifdetach(struct ifnet *ifp) 981 { 982 if (IFP2AC(ifp)->ac_netgraph != NULL) { 983 KASSERT(ng_ether_detach_p != NULL, 984 ("ng_ether_detach_p is NULL")); 985 (*ng_ether_detach_p)(ifp); 986 } 987 988 bpfdetach(ifp); 989 if_detach(ifp); 990 } 991 992 #ifdef VIMAGE 993 void 994 ether_reassign(struct ifnet *ifp, struct vnet *new_vnet, char *unused __unused) 995 { 996 997 if (IFP2AC(ifp)->ac_netgraph != NULL) { 998 KASSERT(ng_ether_detach_p != NULL, 999 ("ng_ether_detach_p is NULL")); 1000 (*ng_ether_detach_p)(ifp); 1001 } 1002 1003 if (ng_ether_attach_p != NULL) { 1004 CURVNET_SET_QUIET(new_vnet); 1005 (*ng_ether_attach_p)(ifp); 1006 CURVNET_RESTORE(); 1007 } 1008 } 1009 #endif 1010 1011 SYSCTL_DECL(_net_link); 1012 SYSCTL_NODE(_net_link, IFT_ETHER, ether, CTLFLAG_RW, 0, "Ethernet"); 1013 #if defined(INET) || defined(INET6) 1014 SYSCTL_VNET_INT(_net_link_ether, OID_AUTO, ipfw, CTLFLAG_RW, 1015 &VNET_NAME(ether_ipfw), 0, "Pass ether pkts through firewall"); 1016 #endif 1017 1018 #if 0 1019 /* 1020 * This is for reference. We have a table-driven version 1021 * of the little-endian crc32 generator, which is faster 1022 * than the double-loop. 1023 */ 1024 uint32_t 1025 ether_crc32_le(const uint8_t *buf, size_t len) 1026 { 1027 size_t i; 1028 uint32_t crc; 1029 int bit; 1030 uint8_t data; 1031 1032 crc = 0xffffffff; /* initial value */ 1033 1034 for (i = 0; i < len; i++) { 1035 for (data = *buf++, bit = 0; bit < 8; bit++, data >>= 1) { 1036 carry = (crc ^ data) & 1; 1037 crc >>= 1; 1038 if (carry) 1039 crc = (crc ^ ETHER_CRC_POLY_LE); 1040 } 1041 } 1042 1043 return (crc); 1044 } 1045 #else 1046 uint32_t 1047 ether_crc32_le(const uint8_t *buf, size_t len) 1048 { 1049 static const uint32_t crctab[] = { 1050 0x00000000, 0x1db71064, 0x3b6e20c8, 0x26d930ac, 1051 0x76dc4190, 0x6b6b51f4, 0x4db26158, 0x5005713c, 1052 0xedb88320, 0xf00f9344, 0xd6d6a3e8, 0xcb61b38c, 1053 0x9b64c2b0, 0x86d3d2d4, 0xa00ae278, 0xbdbdf21c 1054 }; 1055 size_t i; 1056 uint32_t crc; 1057 1058 crc = 0xffffffff; /* initial value */ 1059 1060 for (i = 0; i < len; i++) { 1061 crc ^= buf[i]; 1062 crc = (crc >> 4) ^ crctab[crc & 0xf]; 1063 crc = (crc >> 4) ^ crctab[crc & 0xf]; 1064 } 1065 1066 return (crc); 1067 } 1068 #endif 1069 1070 uint32_t 1071 ether_crc32_be(const uint8_t *buf, size_t len) 1072 { 1073 size_t i; 1074 uint32_t crc, carry; 1075 int bit; 1076 uint8_t data; 1077 1078 crc = 0xffffffff; /* initial value */ 1079 1080 for (i = 0; i < len; i++) { 1081 for (data = *buf++, bit = 0; bit < 8; bit++, data >>= 1) { 1082 carry = ((crc & 0x80000000) ? 1 : 0) ^ (data & 0x01); 1083 crc <<= 1; 1084 if (carry) 1085 crc = (crc ^ ETHER_CRC_POLY_BE) | carry; 1086 } 1087 } 1088 1089 return (crc); 1090 } 1091 1092 int 1093 ether_ioctl(struct ifnet *ifp, u_long command, caddr_t data) 1094 { 1095 struct ifaddr *ifa = (struct ifaddr *) data; 1096 struct ifreq *ifr = (struct ifreq *) data; 1097 int error = 0; 1098 1099 switch (command) { 1100 case SIOCSIFADDR: 1101 ifp->if_flags |= IFF_UP; 1102 1103 switch (ifa->ifa_addr->sa_family) { 1104 #ifdef INET 1105 case AF_INET: 1106 ifp->if_init(ifp->if_softc); /* before arpwhohas */ 1107 arp_ifinit(ifp, ifa); 1108 break; 1109 #endif 1110 #ifdef IPX 1111 /* 1112 * XXX - This code is probably wrong 1113 */ 1114 case AF_IPX: 1115 { 1116 struct ipx_addr *ina = &(IA_SIPX(ifa)->sipx_addr); 1117 1118 if (ipx_nullhost(*ina)) 1119 ina->x_host = 1120 *(union ipx_host *) 1121 IF_LLADDR(ifp); 1122 else { 1123 bcopy((caddr_t) ina->x_host.c_host, 1124 (caddr_t) IF_LLADDR(ifp), 1125 ETHER_ADDR_LEN); 1126 } 1127 1128 /* 1129 * Set new address 1130 */ 1131 ifp->if_init(ifp->if_softc); 1132 break; 1133 } 1134 #endif 1135 default: 1136 ifp->if_init(ifp->if_softc); 1137 break; 1138 } 1139 break; 1140 1141 case SIOCGIFADDR: 1142 { 1143 struct sockaddr *sa; 1144 1145 sa = (struct sockaddr *) & ifr->ifr_data; 1146 bcopy(IF_LLADDR(ifp), 1147 (caddr_t) sa->sa_data, ETHER_ADDR_LEN); 1148 } 1149 break; 1150 1151 case SIOCSIFMTU: 1152 /* 1153 * Set the interface MTU. 1154 */ 1155 if (ifr->ifr_mtu > ETHERMTU) { 1156 error = EINVAL; 1157 } else { 1158 ifp->if_mtu = ifr->ifr_mtu; 1159 } 1160 break; 1161 default: 1162 error = EINVAL; /* XXX netbsd has ENOTTY??? */ 1163 break; 1164 } 1165 return (error); 1166 } 1167 1168 static int 1169 ether_resolvemulti(struct ifnet *ifp, struct sockaddr **llsa, 1170 struct sockaddr *sa) 1171 { 1172 struct sockaddr_dl *sdl; 1173 #ifdef INET 1174 struct sockaddr_in *sin; 1175 #endif 1176 #ifdef INET6 1177 struct sockaddr_in6 *sin6; 1178 #endif 1179 u_char *e_addr; 1180 1181 switch(sa->sa_family) { 1182 case AF_LINK: 1183 /* 1184 * No mapping needed. Just check that it's a valid MC address. 1185 */ 1186 sdl = (struct sockaddr_dl *)sa; 1187 e_addr = LLADDR(sdl); 1188 if (!ETHER_IS_MULTICAST(e_addr)) 1189 return EADDRNOTAVAIL; 1190 *llsa = 0; 1191 return 0; 1192 1193 #ifdef INET 1194 case AF_INET: 1195 sin = (struct sockaddr_in *)sa; 1196 if (!IN_MULTICAST(ntohl(sin->sin_addr.s_addr))) 1197 return EADDRNOTAVAIL; 1198 sdl = malloc(sizeof *sdl, M_IFMADDR, 1199 M_NOWAIT|M_ZERO); 1200 if (sdl == NULL) 1201 return ENOMEM; 1202 sdl->sdl_len = sizeof *sdl; 1203 sdl->sdl_family = AF_LINK; 1204 sdl->sdl_index = ifp->if_index; 1205 sdl->sdl_type = IFT_ETHER; 1206 sdl->sdl_alen = ETHER_ADDR_LEN; 1207 e_addr = LLADDR(sdl); 1208 ETHER_MAP_IP_MULTICAST(&sin->sin_addr, e_addr); 1209 *llsa = (struct sockaddr *)sdl; 1210 return 0; 1211 #endif 1212 #ifdef INET6 1213 case AF_INET6: 1214 sin6 = (struct sockaddr_in6 *)sa; 1215 if (IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr)) { 1216 /* 1217 * An IP6 address of 0 means listen to all 1218 * of the Ethernet multicast address used for IP6. 1219 * (This is used for multicast routers.) 1220 */ 1221 ifp->if_flags |= IFF_ALLMULTI; 1222 *llsa = 0; 1223 return 0; 1224 } 1225 if (!IN6_IS_ADDR_MULTICAST(&sin6->sin6_addr)) 1226 return EADDRNOTAVAIL; 1227 sdl = malloc(sizeof *sdl, M_IFMADDR, 1228 M_NOWAIT|M_ZERO); 1229 if (sdl == NULL) 1230 return (ENOMEM); 1231 sdl->sdl_len = sizeof *sdl; 1232 sdl->sdl_family = AF_LINK; 1233 sdl->sdl_index = ifp->if_index; 1234 sdl->sdl_type = IFT_ETHER; 1235 sdl->sdl_alen = ETHER_ADDR_LEN; 1236 e_addr = LLADDR(sdl); 1237 ETHER_MAP_IPV6_MULTICAST(&sin6->sin6_addr, e_addr); 1238 *llsa = (struct sockaddr *)sdl; 1239 return 0; 1240 #endif 1241 1242 default: 1243 /* 1244 * Well, the text isn't quite right, but it's the name 1245 * that counts... 1246 */ 1247 return EAFNOSUPPORT; 1248 } 1249 } 1250 1251 static void* 1252 ether_alloc(u_char type, struct ifnet *ifp) 1253 { 1254 struct arpcom *ac; 1255 1256 ac = malloc(sizeof(struct arpcom), M_ARPCOM, M_WAITOK | M_ZERO); 1257 ac->ac_ifp = ifp; 1258 1259 return (ac); 1260 } 1261 1262 static void 1263 ether_free(void *com, u_char type) 1264 { 1265 1266 free(com, M_ARPCOM); 1267 } 1268 1269 static int 1270 ether_modevent(module_t mod, int type, void *data) 1271 { 1272 1273 switch (type) { 1274 case MOD_LOAD: 1275 if_register_com_alloc(IFT_ETHER, ether_alloc, ether_free); 1276 break; 1277 case MOD_UNLOAD: 1278 if_deregister_com_alloc(IFT_ETHER); 1279 break; 1280 default: 1281 return EOPNOTSUPP; 1282 } 1283 1284 return (0); 1285 } 1286 1287 static moduledata_t ether_mod = { 1288 "ether", 1289 ether_modevent, 1290 0 1291 }; 1292 1293 void 1294 ether_vlan_mtap(struct bpf_if *bp, struct mbuf *m, void *data, u_int dlen) 1295 { 1296 struct ether_vlan_header vlan; 1297 struct mbuf mv, mb; 1298 1299 KASSERT((m->m_flags & M_VLANTAG) != 0, 1300 ("%s: vlan information not present", __func__)); 1301 KASSERT(m->m_len >= sizeof(struct ether_header), 1302 ("%s: mbuf not large enough for header", __func__)); 1303 bcopy(mtod(m, char *), &vlan, sizeof(struct ether_header)); 1304 vlan.evl_proto = vlan.evl_encap_proto; 1305 vlan.evl_encap_proto = htons(ETHERTYPE_VLAN); 1306 vlan.evl_tag = htons(m->m_pkthdr.ether_vtag); 1307 m->m_len -= sizeof(struct ether_header); 1308 m->m_data += sizeof(struct ether_header); 1309 /* 1310 * If a data link has been supplied by the caller, then we will need to 1311 * re-create a stack allocated mbuf chain with the following structure: 1312 * 1313 * (1) mbuf #1 will contain the supplied data link 1314 * (2) mbuf #2 will contain the vlan header 1315 * (3) mbuf #3 will contain the original mbuf's packet data 1316 * 1317 * Otherwise, submit the packet and vlan header via bpf_mtap2(). 1318 */ 1319 if (data != NULL) { 1320 mv.m_next = m; 1321 mv.m_data = (caddr_t)&vlan; 1322 mv.m_len = sizeof(vlan); 1323 mb.m_next = &mv; 1324 mb.m_data = data; 1325 mb.m_len = dlen; 1326 bpf_mtap(bp, &mb); 1327 } else 1328 bpf_mtap2(bp, &vlan, sizeof(vlan), m); 1329 m->m_len += sizeof(struct ether_header); 1330 m->m_data -= sizeof(struct ether_header); 1331 } 1332 1333 struct mbuf * 1334 ether_vlanencap(struct mbuf *m, uint16_t tag) 1335 { 1336 struct ether_vlan_header *evl; 1337 1338 M_PREPEND(m, ETHER_VLAN_ENCAP_LEN, M_DONTWAIT); 1339 if (m == NULL) 1340 return (NULL); 1341 /* M_PREPEND takes care of m_len, m_pkthdr.len for us */ 1342 1343 if (m->m_len < sizeof(*evl)) { 1344 m = m_pullup(m, sizeof(*evl)); 1345 if (m == NULL) 1346 return (NULL); 1347 } 1348 1349 /* 1350 * Transform the Ethernet header into an Ethernet header 1351 * with 802.1Q encapsulation. 1352 */ 1353 evl = mtod(m, struct ether_vlan_header *); 1354 bcopy((char *)evl + ETHER_VLAN_ENCAP_LEN, 1355 (char *)evl, ETHER_HDR_LEN - ETHER_TYPE_LEN); 1356 evl->evl_encap_proto = htons(ETHERTYPE_VLAN); 1357 evl->evl_tag = htons(tag); 1358 return (m); 1359 } 1360 1361 DECLARE_MODULE(ether, ether_mod, SI_SUB_INIT_IF, SI_ORDER_ANY); 1362 MODULE_VERSION(ether, 1); 1363