if_ethersubr.c revision 223741
1/*- 2 * Copyright (c) 1982, 1989, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 4. Neither the name of the University nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * @(#)if_ethersubr.c 8.1 (Berkeley) 6/10/93 30 * $FreeBSD: head/sys/net/if_ethersubr.c 223741 2011-07-03 16:08:38Z bz $ 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 86int (*ef_inputp)(struct ifnet*, struct ether_header *eh, struct mbuf *m); 87int (*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 98extern u_char at_org_code[3]; 99extern u_char aarp_org_code[3]; 100#endif /* NETATALK */ 101 102#include <security/mac/mac_framework.h> 103 104#ifdef CTASSERT 105CTASSERT(sizeof (struct ether_header) == ETHER_ADDR_LEN * 2 + 2); 106CTASSERT(sizeof (struct ether_addr) == ETHER_ADDR_LEN); 107#endif 108 109/* netgraph node hooks for ng_ether(4) */ 110void (*ng_ether_input_p)(struct ifnet *ifp, struct mbuf **mp); 111void (*ng_ether_input_orphan_p)(struct ifnet *ifp, struct mbuf *m); 112int (*ng_ether_output_p)(struct ifnet *ifp, struct mbuf **mp); 113void (*ng_ether_attach_p)(struct ifnet *ifp); 114void (*ng_ether_detach_p)(struct ifnet *ifp); 115 116void (*vlan_input_p)(struct ifnet *, struct mbuf *); 117 118/* if_bridge(4) support */ 119struct mbuf *(*bridge_input_p)(struct ifnet *, struct mbuf *); 120int (*bridge_output_p)(struct ifnet *, struct mbuf *, 121 struct sockaddr *, struct rtentry *); 122void (*bridge_dn_p)(struct mbuf *, struct ifnet *); 123 124/* if_lagg(4) support */ 125struct mbuf *(*lagg_input_p)(struct ifnet *, struct mbuf *); 126 127static const u_char etherbroadcastaddr[ETHER_ADDR_LEN] = 128 { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff }; 129 130static int ether_resolvemulti(struct ifnet *, struct sockaddr **, 131 struct sockaddr *); 132#ifdef VIMAGE 133static void ether_reassign(struct ifnet *, struct vnet *, char *); 134#endif 135 136/* XXX: should be in an arp support file, not here */ 137MALLOC_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) 145int 146ether_ipfw_chk(struct mbuf **m0, struct ifnet *dst, int shared); 147static 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 */ 158int 159ether_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) { 409bad: 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 */ 427int 428ether_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 */ 456int 457ether_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 */ 563static void 564ether_input_internal(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 M_SETFIB(m, ifp->if_fib); 696 697 /* Allow ng_ether(4) to claim this frame. */ 698 if (IFP2AC(ifp)->ac_netgraph != NULL) { 699 KASSERT(ng_ether_input_p != NULL, 700 ("%s: ng_ether_input_p is NULL", __func__)); 701 m->m_flags &= ~M_PROMISC; 702 (*ng_ether_input_p)(ifp, &m); 703 if (m == NULL) { 704 CURVNET_RESTORE(); 705 return; 706 } 707 } 708 709 /* 710 * Allow if_bridge(4) to claim this frame. 711 * The BRIDGE_INPUT() macro will update ifp if the bridge changed it 712 * and the frame should be delivered locally. 713 */ 714 if (ifp->if_bridge != NULL) { 715 m->m_flags &= ~M_PROMISC; 716 BRIDGE_INPUT(ifp, m); 717 if (m == NULL) { 718 CURVNET_RESTORE(); 719 return; 720 } 721 } 722 723#if defined(INET) || defined(INET6) 724 /* 725 * Clear M_PROMISC on frame so that carp(4) will see it when the 726 * mbuf flows up to Layer 3. 727 * FreeBSD's implementation of carp(4) uses the inprotosw 728 * to dispatch IPPROTO_CARP. carp(4) also allocates its own 729 * Ethernet addresses of the form 00:00:5e:00:01:xx, which 730 * is outside the scope of the M_PROMISC test below. 731 * TODO: Maintain a hash table of ethernet addresses other than 732 * ether_dhost which may be active on this ifp. 733 */ 734 if (ifp->if_carp && (*carp_forus_p)(ifp, eh->ether_dhost)) { 735 m->m_flags &= ~M_PROMISC; 736 } else 737#endif 738 { 739 /* 740 * If the frame received was not for our MAC address, set the 741 * M_PROMISC flag on the mbuf chain. The frame may need to 742 * be seen by the rest of the Ethernet input path in case of 743 * re-entry (e.g. bridge, vlan, netgraph) but should not be 744 * seen by upper protocol layers. 745 */ 746 if (!ETHER_IS_MULTICAST(eh->ether_dhost) && 747 bcmp(IF_LLADDR(ifp), eh->ether_dhost, ETHER_ADDR_LEN) != 0) 748 m->m_flags |= M_PROMISC; 749 } 750 751 /* First chunk of an mbuf contains good entropy */ 752 if (harvest.ethernet) 753 random_harvest(m, 16, 3, 0, RANDOM_NET); 754 755 ether_demux(ifp, m); 756 CURVNET_RESTORE(); 757} 758 759/* 760 * Ethernet input dispatch; by default, direct dispatch here regardless of 761 * global configuration. 762 */ 763static void 764ether_nh_input(struct mbuf *m) 765{ 766 767 ether_input_internal(m->m_pkthdr.rcvif, m); 768} 769 770static struct netisr_handler ether_nh = { 771 .nh_name = "ether", 772 .nh_handler = ether_nh_input, 773 .nh_proto = NETISR_ETHER, 774 .nh_policy = NETISR_POLICY_SOURCE, 775 .nh_dispatch = NETISR_DISPATCH_DIRECT, 776}; 777 778static void 779ether_init(__unused void *arg) 780{ 781 782 netisr_register(ðer_nh); 783} 784SYSINIT(ether, SI_SUB_INIT_IF, SI_ORDER_ANY, ether_init, NULL); 785 786static void 787ether_input(struct ifnet *ifp, struct mbuf *m) 788{ 789 790 /* 791 * We will rely on rcvif being set properly in the deferred context, 792 * so assert it is correct here. 793 */ 794 KASSERT(m->m_pkthdr.rcvif == ifp, ("%s: ifnet mismatch", __func__)); 795 796 netisr_dispatch(NETISR_ETHER, m); 797} 798 799/* 800 * Upper layer processing for a received Ethernet packet. 801 */ 802void 803ether_demux(struct ifnet *ifp, struct mbuf *m) 804{ 805 struct ether_header *eh; 806 int isr; 807 u_short ether_type; 808#if defined(NETATALK) 809 struct llc *l; 810#endif 811 812 KASSERT(ifp != NULL, ("%s: NULL interface pointer", __func__)); 813 814#if defined(INET) || defined(INET6) 815 /* 816 * Allow dummynet and/or ipfw to claim the frame. 817 * Do not do this for PROMISC frames in case we are re-entered. 818 */ 819 if (V_ip_fw_chk_ptr && V_ether_ipfw != 0 && !(m->m_flags & M_PROMISC)) { 820 if (ether_ipfw_chk(&m, NULL, 0) == 0) { 821 if (m) 822 m_freem(m); /* dropped; free mbuf chain */ 823 return; /* consumed */ 824 } 825 } 826#endif 827 eh = mtod(m, struct ether_header *); 828 ether_type = ntohs(eh->ether_type); 829 830 /* 831 * If this frame has a VLAN tag other than 0, call vlan_input() 832 * if its module is loaded. Otherwise, drop. 833 */ 834 if ((m->m_flags & M_VLANTAG) && 835 EVL_VLANOFTAG(m->m_pkthdr.ether_vtag) != 0) { 836 if (ifp->if_vlantrunk == NULL) { 837 ifp->if_noproto++; 838 m_freem(m); 839 return; 840 } 841 KASSERT(vlan_input_p != NULL,("%s: VLAN not loaded!", 842 __func__)); 843 /* Clear before possibly re-entering ether_input(). */ 844 m->m_flags &= ~M_PROMISC; 845 (*vlan_input_p)(ifp, m); 846 return; 847 } 848 849 /* 850 * Pass promiscuously received frames to the upper layer if the user 851 * requested this by setting IFF_PPROMISC. Otherwise, drop them. 852 */ 853 if ((ifp->if_flags & IFF_PPROMISC) == 0 && (m->m_flags & M_PROMISC)) { 854 m_freem(m); 855 return; 856 } 857 858 /* 859 * Reset layer specific mbuf flags to avoid confusing upper layers. 860 * Strip off Ethernet header. 861 */ 862 m->m_flags &= ~M_VLANTAG; 863 m->m_flags &= ~(M_PROTOFLAGS); 864 m_adj(m, ETHER_HDR_LEN); 865 866 /* 867 * Dispatch frame to upper layer. 868 */ 869 switch (ether_type) { 870#ifdef INET 871 case ETHERTYPE_IP: 872 if ((m = ip_fastforward(m)) == NULL) 873 return; 874 isr = NETISR_IP; 875 break; 876 877 case ETHERTYPE_ARP: 878 if (ifp->if_flags & IFF_NOARP) { 879 /* Discard packet if ARP is disabled on interface */ 880 m_freem(m); 881 return; 882 } 883 isr = NETISR_ARP; 884 break; 885#endif 886#ifdef IPX 887 case ETHERTYPE_IPX: 888 if (ef_inputp && ef_inputp(ifp, eh, m) == 0) 889 return; 890 isr = NETISR_IPX; 891 break; 892#endif 893#ifdef INET6 894 case ETHERTYPE_IPV6: 895 isr = NETISR_IPV6; 896 break; 897#endif 898#ifdef NETATALK 899 case ETHERTYPE_AT: 900 isr = NETISR_ATALK1; 901 break; 902 case ETHERTYPE_AARP: 903 isr = NETISR_AARP; 904 break; 905#endif /* NETATALK */ 906 default: 907#ifdef IPX 908 if (ef_inputp && ef_inputp(ifp, eh, m) == 0) 909 return; 910#endif /* IPX */ 911#if defined(NETATALK) 912 if (ether_type > ETHERMTU) 913 goto discard; 914 l = mtod(m, struct llc *); 915 if (l->llc_dsap == LLC_SNAP_LSAP && 916 l->llc_ssap == LLC_SNAP_LSAP && 917 l->llc_control == LLC_UI) { 918 if (bcmp(&(l->llc_snap_org_code)[0], at_org_code, 919 sizeof(at_org_code)) == 0 && 920 ntohs(l->llc_snap_ether_type) == ETHERTYPE_AT) { 921 m_adj(m, LLC_SNAPFRAMELEN); 922 isr = NETISR_ATALK2; 923 break; 924 } 925 if (bcmp(&(l->llc_snap_org_code)[0], aarp_org_code, 926 sizeof(aarp_org_code)) == 0 && 927 ntohs(l->llc_snap_ether_type) == ETHERTYPE_AARP) { 928 m_adj(m, LLC_SNAPFRAMELEN); 929 isr = NETISR_AARP; 930 break; 931 } 932 } 933#endif /* NETATALK */ 934 goto discard; 935 } 936 netisr_dispatch(isr, m); 937 return; 938 939discard: 940 /* 941 * Packet is to be discarded. If netgraph is present, 942 * hand the packet to it for last chance processing; 943 * otherwise dispose of it. 944 */ 945 if (IFP2AC(ifp)->ac_netgraph != NULL) { 946 KASSERT(ng_ether_input_orphan_p != NULL, 947 ("ng_ether_input_orphan_p is NULL")); 948 /* 949 * Put back the ethernet header so netgraph has a 950 * consistent view of inbound packets. 951 */ 952 M_PREPEND(m, ETHER_HDR_LEN, M_DONTWAIT); 953 (*ng_ether_input_orphan_p)(ifp, m); 954 return; 955 } 956 m_freem(m); 957} 958 959/* 960 * Convert Ethernet address to printable (loggable) representation. 961 * This routine is for compatibility; it's better to just use 962 * 963 * printf("%6D", <pointer to address>, ":"); 964 * 965 * since there's no static buffer involved. 966 */ 967char * 968ether_sprintf(const u_char *ap) 969{ 970 static char etherbuf[18]; 971 snprintf(etherbuf, sizeof (etherbuf), "%6D", ap, ":"); 972 return (etherbuf); 973} 974 975/* 976 * Perform common duties while attaching to interface list 977 */ 978void 979ether_ifattach(struct ifnet *ifp, const u_int8_t *lla) 980{ 981 int i; 982 struct ifaddr *ifa; 983 struct sockaddr_dl *sdl; 984 985 ifp->if_addrlen = ETHER_ADDR_LEN; 986 ifp->if_hdrlen = ETHER_HDR_LEN; 987 if_attach(ifp); 988 ifp->if_mtu = ETHERMTU; 989 ifp->if_output = ether_output; 990 ifp->if_input = ether_input; 991 ifp->if_resolvemulti = ether_resolvemulti; 992#ifdef VIMAGE 993 ifp->if_reassign = ether_reassign; 994#endif 995 if (ifp->if_baudrate == 0) 996 ifp->if_baudrate = IF_Mbps(10); /* just a default */ 997 ifp->if_broadcastaddr = etherbroadcastaddr; 998 999 ifa = ifp->if_addr; 1000 KASSERT(ifa != NULL, ("%s: no lladdr!\n", __func__)); 1001 sdl = (struct sockaddr_dl *)ifa->ifa_addr; 1002 sdl->sdl_type = IFT_ETHER; 1003 sdl->sdl_alen = ifp->if_addrlen; 1004 bcopy(lla, LLADDR(sdl), ifp->if_addrlen); 1005 1006 bpfattach(ifp, DLT_EN10MB, ETHER_HDR_LEN); 1007 if (ng_ether_attach_p != NULL) 1008 (*ng_ether_attach_p)(ifp); 1009 1010 /* Announce Ethernet MAC address if non-zero. */ 1011 for (i = 0; i < ifp->if_addrlen; i++) 1012 if (lla[i] != 0) 1013 break; 1014 if (i != ifp->if_addrlen) 1015 if_printf(ifp, "Ethernet address: %6D\n", lla, ":"); 1016} 1017 1018/* 1019 * Perform common duties while detaching an Ethernet interface 1020 */ 1021void 1022ether_ifdetach(struct ifnet *ifp) 1023{ 1024 if (IFP2AC(ifp)->ac_netgraph != NULL) { 1025 KASSERT(ng_ether_detach_p != NULL, 1026 ("ng_ether_detach_p is NULL")); 1027 (*ng_ether_detach_p)(ifp); 1028 } 1029 1030 bpfdetach(ifp); 1031 if_detach(ifp); 1032} 1033 1034#ifdef VIMAGE 1035void 1036ether_reassign(struct ifnet *ifp, struct vnet *new_vnet, char *unused __unused) 1037{ 1038 1039 if (IFP2AC(ifp)->ac_netgraph != NULL) { 1040 KASSERT(ng_ether_detach_p != NULL, 1041 ("ng_ether_detach_p is NULL")); 1042 (*ng_ether_detach_p)(ifp); 1043 } 1044 1045 if (ng_ether_attach_p != NULL) { 1046 CURVNET_SET_QUIET(new_vnet); 1047 (*ng_ether_attach_p)(ifp); 1048 CURVNET_RESTORE(); 1049 } 1050} 1051#endif 1052 1053SYSCTL_DECL(_net_link); 1054SYSCTL_NODE(_net_link, IFT_ETHER, ether, CTLFLAG_RW, 0, "Ethernet"); 1055#if defined(INET) || defined(INET6) 1056SYSCTL_VNET_INT(_net_link_ether, OID_AUTO, ipfw, CTLFLAG_RW, 1057 &VNET_NAME(ether_ipfw), 0, "Pass ether pkts through firewall"); 1058#endif 1059 1060#if 0 1061/* 1062 * This is for reference. We have a table-driven version 1063 * of the little-endian crc32 generator, which is faster 1064 * than the double-loop. 1065 */ 1066uint32_t 1067ether_crc32_le(const uint8_t *buf, size_t len) 1068{ 1069 size_t i; 1070 uint32_t crc; 1071 int bit; 1072 uint8_t data; 1073 1074 crc = 0xffffffff; /* initial value */ 1075 1076 for (i = 0; i < len; i++) { 1077 for (data = *buf++, bit = 0; bit < 8; bit++, data >>= 1) { 1078 carry = (crc ^ data) & 1; 1079 crc >>= 1; 1080 if (carry) 1081 crc = (crc ^ ETHER_CRC_POLY_LE); 1082 } 1083 } 1084 1085 return (crc); 1086} 1087#else 1088uint32_t 1089ether_crc32_le(const uint8_t *buf, size_t len) 1090{ 1091 static const uint32_t crctab[] = { 1092 0x00000000, 0x1db71064, 0x3b6e20c8, 0x26d930ac, 1093 0x76dc4190, 0x6b6b51f4, 0x4db26158, 0x5005713c, 1094 0xedb88320, 0xf00f9344, 0xd6d6a3e8, 0xcb61b38c, 1095 0x9b64c2b0, 0x86d3d2d4, 0xa00ae278, 0xbdbdf21c 1096 }; 1097 size_t i; 1098 uint32_t crc; 1099 1100 crc = 0xffffffff; /* initial value */ 1101 1102 for (i = 0; i < len; i++) { 1103 crc ^= buf[i]; 1104 crc = (crc >> 4) ^ crctab[crc & 0xf]; 1105 crc = (crc >> 4) ^ crctab[crc & 0xf]; 1106 } 1107 1108 return (crc); 1109} 1110#endif 1111 1112uint32_t 1113ether_crc32_be(const uint8_t *buf, size_t len) 1114{ 1115 size_t i; 1116 uint32_t crc, carry; 1117 int bit; 1118 uint8_t data; 1119 1120 crc = 0xffffffff; /* initial value */ 1121 1122 for (i = 0; i < len; i++) { 1123 for (data = *buf++, bit = 0; bit < 8; bit++, data >>= 1) { 1124 carry = ((crc & 0x80000000) ? 1 : 0) ^ (data & 0x01); 1125 crc <<= 1; 1126 if (carry) 1127 crc = (crc ^ ETHER_CRC_POLY_BE) | carry; 1128 } 1129 } 1130 1131 return (crc); 1132} 1133 1134int 1135ether_ioctl(struct ifnet *ifp, u_long command, caddr_t data) 1136{ 1137 struct ifaddr *ifa = (struct ifaddr *) data; 1138 struct ifreq *ifr = (struct ifreq *) data; 1139 int error = 0; 1140 1141 switch (command) { 1142 case SIOCSIFADDR: 1143 ifp->if_flags |= IFF_UP; 1144 1145 switch (ifa->ifa_addr->sa_family) { 1146#ifdef INET 1147 case AF_INET: 1148 ifp->if_init(ifp->if_softc); /* before arpwhohas */ 1149 arp_ifinit(ifp, ifa); 1150 break; 1151#endif 1152#ifdef IPX 1153 /* 1154 * XXX - This code is probably wrong 1155 */ 1156 case AF_IPX: 1157 { 1158 struct ipx_addr *ina = &(IA_SIPX(ifa)->sipx_addr); 1159 1160 if (ipx_nullhost(*ina)) 1161 ina->x_host = 1162 *(union ipx_host *) 1163 IF_LLADDR(ifp); 1164 else { 1165 bcopy((caddr_t) ina->x_host.c_host, 1166 (caddr_t) IF_LLADDR(ifp), 1167 ETHER_ADDR_LEN); 1168 } 1169 1170 /* 1171 * Set new address 1172 */ 1173 ifp->if_init(ifp->if_softc); 1174 break; 1175 } 1176#endif 1177 default: 1178 ifp->if_init(ifp->if_softc); 1179 break; 1180 } 1181 break; 1182 1183 case SIOCGIFADDR: 1184 { 1185 struct sockaddr *sa; 1186 1187 sa = (struct sockaddr *) & ifr->ifr_data; 1188 bcopy(IF_LLADDR(ifp), 1189 (caddr_t) sa->sa_data, ETHER_ADDR_LEN); 1190 } 1191 break; 1192 1193 case SIOCSIFMTU: 1194 /* 1195 * Set the interface MTU. 1196 */ 1197 if (ifr->ifr_mtu > ETHERMTU) { 1198 error = EINVAL; 1199 } else { 1200 ifp->if_mtu = ifr->ifr_mtu; 1201 } 1202 break; 1203 default: 1204 error = EINVAL; /* XXX netbsd has ENOTTY??? */ 1205 break; 1206 } 1207 return (error); 1208} 1209 1210static int 1211ether_resolvemulti(struct ifnet *ifp, struct sockaddr **llsa, 1212 struct sockaddr *sa) 1213{ 1214 struct sockaddr_dl *sdl; 1215#ifdef INET 1216 struct sockaddr_in *sin; 1217#endif 1218#ifdef INET6 1219 struct sockaddr_in6 *sin6; 1220#endif 1221 u_char *e_addr; 1222 1223 switch(sa->sa_family) { 1224 case AF_LINK: 1225 /* 1226 * No mapping needed. Just check that it's a valid MC address. 1227 */ 1228 sdl = (struct sockaddr_dl *)sa; 1229 e_addr = LLADDR(sdl); 1230 if (!ETHER_IS_MULTICAST(e_addr)) 1231 return EADDRNOTAVAIL; 1232 *llsa = 0; 1233 return 0; 1234 1235#ifdef INET 1236 case AF_INET: 1237 sin = (struct sockaddr_in *)sa; 1238 if (!IN_MULTICAST(ntohl(sin->sin_addr.s_addr))) 1239 return EADDRNOTAVAIL; 1240 sdl = malloc(sizeof *sdl, M_IFMADDR, 1241 M_NOWAIT|M_ZERO); 1242 if (sdl == NULL) 1243 return ENOMEM; 1244 sdl->sdl_len = sizeof *sdl; 1245 sdl->sdl_family = AF_LINK; 1246 sdl->sdl_index = ifp->if_index; 1247 sdl->sdl_type = IFT_ETHER; 1248 sdl->sdl_alen = ETHER_ADDR_LEN; 1249 e_addr = LLADDR(sdl); 1250 ETHER_MAP_IP_MULTICAST(&sin->sin_addr, e_addr); 1251 *llsa = (struct sockaddr *)sdl; 1252 return 0; 1253#endif 1254#ifdef INET6 1255 case AF_INET6: 1256 sin6 = (struct sockaddr_in6 *)sa; 1257 if (IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr)) { 1258 /* 1259 * An IP6 address of 0 means listen to all 1260 * of the Ethernet multicast address used for IP6. 1261 * (This is used for multicast routers.) 1262 */ 1263 ifp->if_flags |= IFF_ALLMULTI; 1264 *llsa = 0; 1265 return 0; 1266 } 1267 if (!IN6_IS_ADDR_MULTICAST(&sin6->sin6_addr)) 1268 return EADDRNOTAVAIL; 1269 sdl = malloc(sizeof *sdl, M_IFMADDR, 1270 M_NOWAIT|M_ZERO); 1271 if (sdl == NULL) 1272 return (ENOMEM); 1273 sdl->sdl_len = sizeof *sdl; 1274 sdl->sdl_family = AF_LINK; 1275 sdl->sdl_index = ifp->if_index; 1276 sdl->sdl_type = IFT_ETHER; 1277 sdl->sdl_alen = ETHER_ADDR_LEN; 1278 e_addr = LLADDR(sdl); 1279 ETHER_MAP_IPV6_MULTICAST(&sin6->sin6_addr, e_addr); 1280 *llsa = (struct sockaddr *)sdl; 1281 return 0; 1282#endif 1283 1284 default: 1285 /* 1286 * Well, the text isn't quite right, but it's the name 1287 * that counts... 1288 */ 1289 return EAFNOSUPPORT; 1290 } 1291} 1292 1293static void* 1294ether_alloc(u_char type, struct ifnet *ifp) 1295{ 1296 struct arpcom *ac; 1297 1298 ac = malloc(sizeof(struct arpcom), M_ARPCOM, M_WAITOK | M_ZERO); 1299 ac->ac_ifp = ifp; 1300 1301 return (ac); 1302} 1303 1304static void 1305ether_free(void *com, u_char type) 1306{ 1307 1308 free(com, M_ARPCOM); 1309} 1310 1311static int 1312ether_modevent(module_t mod, int type, void *data) 1313{ 1314 1315 switch (type) { 1316 case MOD_LOAD: 1317 if_register_com_alloc(IFT_ETHER, ether_alloc, ether_free); 1318 break; 1319 case MOD_UNLOAD: 1320 if_deregister_com_alloc(IFT_ETHER); 1321 break; 1322 default: 1323 return EOPNOTSUPP; 1324 } 1325 1326 return (0); 1327} 1328 1329static moduledata_t ether_mod = { 1330 "ether", 1331 ether_modevent, 1332 0 1333}; 1334 1335void 1336ether_vlan_mtap(struct bpf_if *bp, struct mbuf *m, void *data, u_int dlen) 1337{ 1338 struct ether_vlan_header vlan; 1339 struct mbuf mv, mb; 1340 1341 KASSERT((m->m_flags & M_VLANTAG) != 0, 1342 ("%s: vlan information not present", __func__)); 1343 KASSERT(m->m_len >= sizeof(struct ether_header), 1344 ("%s: mbuf not large enough for header", __func__)); 1345 bcopy(mtod(m, char *), &vlan, sizeof(struct ether_header)); 1346 vlan.evl_proto = vlan.evl_encap_proto; 1347 vlan.evl_encap_proto = htons(ETHERTYPE_VLAN); 1348 vlan.evl_tag = htons(m->m_pkthdr.ether_vtag); 1349 m->m_len -= sizeof(struct ether_header); 1350 m->m_data += sizeof(struct ether_header); 1351 /* 1352 * If a data link has been supplied by the caller, then we will need to 1353 * re-create a stack allocated mbuf chain with the following structure: 1354 * 1355 * (1) mbuf #1 will contain the supplied data link 1356 * (2) mbuf #2 will contain the vlan header 1357 * (3) mbuf #3 will contain the original mbuf's packet data 1358 * 1359 * Otherwise, submit the packet and vlan header via bpf_mtap2(). 1360 */ 1361 if (data != NULL) { 1362 mv.m_next = m; 1363 mv.m_data = (caddr_t)&vlan; 1364 mv.m_len = sizeof(vlan); 1365 mb.m_next = &mv; 1366 mb.m_data = data; 1367 mb.m_len = dlen; 1368 bpf_mtap(bp, &mb); 1369 } else 1370 bpf_mtap2(bp, &vlan, sizeof(vlan), m); 1371 m->m_len += sizeof(struct ether_header); 1372 m->m_data -= sizeof(struct ether_header); 1373} 1374 1375struct mbuf * 1376ether_vlanencap(struct mbuf *m, uint16_t tag) 1377{ 1378 struct ether_vlan_header *evl; 1379 1380 M_PREPEND(m, ETHER_VLAN_ENCAP_LEN, M_DONTWAIT); 1381 if (m == NULL) 1382 return (NULL); 1383 /* M_PREPEND takes care of m_len, m_pkthdr.len for us */ 1384 1385 if (m->m_len < sizeof(*evl)) { 1386 m = m_pullup(m, sizeof(*evl)); 1387 if (m == NULL) 1388 return (NULL); 1389 } 1390 1391 /* 1392 * Transform the Ethernet header into an Ethernet header 1393 * with 802.1Q encapsulation. 1394 */ 1395 evl = mtod(m, struct ether_vlan_header *); 1396 bcopy((char *)evl + ETHER_VLAN_ENCAP_LEN, 1397 (char *)evl, ETHER_HDR_LEN - ETHER_TYPE_LEN); 1398 evl->evl_encap_proto = htons(ETHERTYPE_VLAN); 1399 evl->evl_tag = htons(tag); 1400 return (m); 1401} 1402 1403DECLARE_MODULE(ether, ether_mod, SI_SUB_INIT_IF, SI_ORDER_ANY); 1404MODULE_VERSION(ether, 1); 1405