1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1982, 1989, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 * 31 * @(#)if_ethersubr.c 8.1 (Berkeley) 6/10/93 32 * $FreeBSD$ 33 */ 34 35 #include "opt_inet.h" 36 #include "opt_inet6.h" 37 #include "opt_netgraph.h" 38 #include "opt_mbuf_profiling.h" 39 #include "opt_rss.h" 40 41 #include <sys/param.h> 42 #include <sys/systm.h> 43 #include <sys/bus.h> 44 #include <sys/eventhandler.h> 45 #include <sys/jail.h> 46 #include <sys/kernel.h> 47 #include <sys/lock.h> 48 #include <sys/malloc.h> 49 #include <sys/module.h> 50 #include <sys/mbuf.h> 51 #include <sys/proc.h> 52 #include <sys/priv.h> 53 #include <sys/random.h> 54 #include <sys/socket.h> 55 #include <sys/sockio.h> 56 #include <sys/sysctl.h> 57 #include <sys/uuid.h> 58 59 #include <net/ieee_oui.h> 60 #include <net/if.h> 61 #include <net/if_var.h> 62 #include <net/if_arp.h> 63 #include <net/netisr.h> 64 #include <net/route.h> 65 #include <net/if_llc.h> 66 #include <net/if_dl.h> 67 #include <net/if_types.h> 68 #include <net/bpf.h> 69 #include <net/ethernet.h> 70 #include <net/if_bridgevar.h> 71 #include <net/if_vlan_var.h> 72 #include <net/if_llatbl.h> 73 #include <net/pfil.h> 74 #include <net/rss_config.h> 75 #include <net/vnet.h> 76 77 #include <netpfil/pf/pf_mtag.h> 78 79 #if defined(INET) || defined(INET6) 80 #include <netinet/in.h> 81 #include <netinet/in_var.h> 82 #include <netinet/if_ether.h> 83 #include <netinet/ip_carp.h> 84 #include <netinet/ip_var.h> 85 #endif 86 #ifdef INET6 87 #include <netinet6/nd6.h> 88 #endif 89 #include <security/mac/mac_framework.h> 90 91 #include <crypto/sha1.h> 92 93 #ifdef CTASSERT 94 CTASSERT(sizeof (struct ether_header) == ETHER_ADDR_LEN * 2 + 2); 95 CTASSERT(sizeof (struct ether_addr) == ETHER_ADDR_LEN); 96 #endif 97 98 VNET_DEFINE(pfil_head_t, link_pfil_head); /* Packet filter hooks */ 99 100 /* netgraph node hooks for ng_ether(4) */ 101 void (*ng_ether_input_p)(struct ifnet *ifp, struct mbuf **mp); 102 void (*ng_ether_input_orphan_p)(struct ifnet *ifp, struct mbuf *m); 103 int (*ng_ether_output_p)(struct ifnet *ifp, struct mbuf **mp); 104 void (*ng_ether_attach_p)(struct ifnet *ifp); 105 void (*ng_ether_detach_p)(struct ifnet *ifp); 106 107 void (*vlan_input_p)(struct ifnet *, struct mbuf *); 108 109 /* if_bridge(4) support */ 110 void (*bridge_dn_p)(struct mbuf *, struct ifnet *); 111 112 /* if_lagg(4) support */ 113 struct mbuf *(*lagg_input_p)(struct ifnet *, struct mbuf *); 114 115 static const u_char etherbroadcastaddr[ETHER_ADDR_LEN] = 116 { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff }; 117 118 static int ether_resolvemulti(struct ifnet *, struct sockaddr **, 119 struct sockaddr *); 120 #ifdef VIMAGE 121 static void ether_reassign(struct ifnet *, struct vnet *, char *); 122 #endif 123 static int ether_requestencap(struct ifnet *, struct if_encap_req *); 124 125 126 #define senderr(e) do { error = (e); goto bad;} while (0) 127 128 static void 129 update_mbuf_csumflags(struct mbuf *src, struct mbuf *dst) 130 { 131 int csum_flags = 0; 132 133 if (src->m_pkthdr.csum_flags & CSUM_IP) 134 csum_flags |= (CSUM_IP_CHECKED|CSUM_IP_VALID); 135 if (src->m_pkthdr.csum_flags & CSUM_DELAY_DATA) 136 csum_flags |= (CSUM_DATA_VALID|CSUM_PSEUDO_HDR); 137 if (src->m_pkthdr.csum_flags & CSUM_SCTP) 138 csum_flags |= CSUM_SCTP_VALID; 139 dst->m_pkthdr.csum_flags |= csum_flags; 140 if (csum_flags & CSUM_DATA_VALID) 141 dst->m_pkthdr.csum_data = 0xffff; 142 } 143 144 /* 145 * Handle link-layer encapsulation requests. 146 */ 147 static int 148 ether_requestencap(struct ifnet *ifp, struct if_encap_req *req) 149 { 150 struct ether_header *eh; 151 struct arphdr *ah; 152 uint16_t etype; 153 const u_char *lladdr; 154 155 if (req->rtype != IFENCAP_LL) 156 return (EOPNOTSUPP); 157 158 if (req->bufsize < ETHER_HDR_LEN) 159 return (ENOMEM); 160 161 eh = (struct ether_header *)req->buf; 162 lladdr = req->lladdr; 163 req->lladdr_off = 0; 164 165 switch (req->family) { 166 case AF_INET: 167 etype = htons(ETHERTYPE_IP); 168 break; 169 case AF_INET6: 170 etype = htons(ETHERTYPE_IPV6); 171 break; 172 case AF_ARP: 173 ah = (struct arphdr *)req->hdata; 174 ah->ar_hrd = htons(ARPHRD_ETHER); 175 176 switch(ntohs(ah->ar_op)) { 177 case ARPOP_REVREQUEST: 178 case ARPOP_REVREPLY: 179 etype = htons(ETHERTYPE_REVARP); 180 break; 181 case ARPOP_REQUEST: 182 case ARPOP_REPLY: 183 default: 184 etype = htons(ETHERTYPE_ARP); 185 break; 186 } 187 188 if (req->flags & IFENCAP_FLAG_BROADCAST) 189 lladdr = ifp->if_broadcastaddr; 190 break; 191 default: 192 return (EAFNOSUPPORT); 193 } 194 195 memcpy(&eh->ether_type, &etype, sizeof(eh->ether_type)); 196 memcpy(eh->ether_dhost, lladdr, ETHER_ADDR_LEN); 197 memcpy(eh->ether_shost, IF_LLADDR(ifp), ETHER_ADDR_LEN); 198 req->bufsize = sizeof(struct ether_header); 199 200 return (0); 201 } 202 203 204 static int 205 ether_resolve_addr(struct ifnet *ifp, struct mbuf *m, 206 const struct sockaddr *dst, struct route *ro, u_char *phdr, 207 uint32_t *pflags, struct llentry **plle) 208 { 209 struct ether_header *eh; 210 uint32_t lleflags = 0; 211 int error = 0; 212 #if defined(INET) || defined(INET6) 213 uint16_t etype; 214 #endif 215 216 if (plle) 217 *plle = NULL; 218 eh = (struct ether_header *)phdr; 219 220 switch (dst->sa_family) { 221 #ifdef INET 222 case AF_INET: 223 if ((m->m_flags & (M_BCAST | M_MCAST)) == 0) 224 error = arpresolve(ifp, 0, m, dst, phdr, &lleflags, 225 plle); 226 else { 227 if (m->m_flags & M_BCAST) 228 memcpy(eh->ether_dhost, ifp->if_broadcastaddr, 229 ETHER_ADDR_LEN); 230 else { 231 const struct in_addr *a; 232 a = &(((const struct sockaddr_in *)dst)->sin_addr); 233 ETHER_MAP_IP_MULTICAST(a, eh->ether_dhost); 234 } 235 etype = htons(ETHERTYPE_IP); 236 memcpy(&eh->ether_type, &etype, sizeof(etype)); 237 memcpy(eh->ether_shost, IF_LLADDR(ifp), ETHER_ADDR_LEN); 238 } 239 break; 240 #endif 241 #ifdef INET6 242 case AF_INET6: 243 if ((m->m_flags & M_MCAST) == 0) 244 error = nd6_resolve(ifp, 0, m, dst, phdr, &lleflags, 245 plle); 246 else { 247 const struct in6_addr *a6; 248 a6 = &(((const struct sockaddr_in6 *)dst)->sin6_addr); 249 ETHER_MAP_IPV6_MULTICAST(a6, eh->ether_dhost); 250 etype = htons(ETHERTYPE_IPV6); 251 memcpy(&eh->ether_type, &etype, sizeof(etype)); 252 memcpy(eh->ether_shost, IF_LLADDR(ifp), ETHER_ADDR_LEN); 253 } 254 break; 255 #endif 256 default: 257 if_printf(ifp, "can't handle af%d\n", dst->sa_family); 258 if (m != NULL) 259 m_freem(m); 260 return (EAFNOSUPPORT); 261 } 262 263 if (error == EHOSTDOWN) { 264 if (ro != NULL && (ro->ro_flags & RT_HAS_GW) != 0) 265 error = EHOSTUNREACH; 266 } 267 268 if (error != 0) 269 return (error); 270 271 *pflags = RT_MAY_LOOP; 272 if (lleflags & LLE_IFADDR) 273 *pflags |= RT_L2_ME; 274 275 return (0); 276 } 277 278 /* 279 * Ethernet output routine. 280 * Encapsulate a packet of type family for the local net. 281 * Use trailer local net encapsulation if enough data in first 282 * packet leaves a multiple of 512 bytes of data in remainder. 283 */ 284 int 285 ether_output(struct ifnet *ifp, struct mbuf *m, 286 const struct sockaddr *dst, struct route *ro) 287 { 288 int error = 0; 289 char linkhdr[ETHER_HDR_LEN], *phdr; 290 struct ether_header *eh; 291 struct pf_mtag *t; 292 int loop_copy = 1; 293 int hlen; /* link layer header length */ 294 uint32_t pflags; 295 struct llentry *lle = NULL; 296 int addref = 0; 297 298 phdr = NULL; 299 pflags = 0; 300 if (ro != NULL) { 301 /* XXX BPF uses ro_prepend */ 302 if (ro->ro_prepend != NULL) { 303 phdr = ro->ro_prepend; 304 hlen = ro->ro_plen; 305 } else if (!(m->m_flags & (M_BCAST | M_MCAST))) { 306 if ((ro->ro_flags & RT_LLE_CACHE) != 0) { 307 lle = ro->ro_lle; 308 if (lle != NULL && 309 (lle->la_flags & LLE_VALID) == 0) { 310 LLE_FREE(lle); 311 lle = NULL; /* redundant */ 312 ro->ro_lle = NULL; 313 } 314 if (lle == NULL) { 315 /* if we lookup, keep cache */ 316 addref = 1; 317 } else 318 /* 319 * Notify LLE code that 320 * the entry was used 321 * by datapath. 322 */ 323 llentry_mark_used(lle); 324 } 325 if (lle != NULL) { 326 phdr = lle->r_linkdata; 327 hlen = lle->r_hdrlen; 328 pflags = lle->r_flags; 329 } 330 } 331 } 332 333 #ifdef MAC 334 error = mac_ifnet_check_transmit(ifp, m); 335 if (error) 336 senderr(error); 337 #endif 338 339 M_PROFILE(m); 340 if (ifp->if_flags & IFF_MONITOR) 341 senderr(ENETDOWN); 342 if (!((ifp->if_flags & IFF_UP) && 343 (ifp->if_drv_flags & IFF_DRV_RUNNING))) 344 senderr(ENETDOWN); 345 346 if (phdr == NULL) { 347 /* No prepend data supplied. Try to calculate ourselves. */ 348 phdr = linkhdr; 349 hlen = ETHER_HDR_LEN; 350 error = ether_resolve_addr(ifp, m, dst, ro, phdr, &pflags, 351 addref ? &lle : NULL); 352 if (addref && lle != NULL) 353 ro->ro_lle = lle; 354 if (error != 0) 355 return (error == EWOULDBLOCK ? 0 : error); 356 } 357 358 if ((pflags & RT_L2_ME) != 0) { 359 update_mbuf_csumflags(m, m); 360 return (if_simloop(ifp, m, dst->sa_family, 0)); 361 } 362 loop_copy = pflags & RT_MAY_LOOP; 363 364 /* 365 * Add local net header. If no space in first mbuf, 366 * allocate another. 367 * 368 * Note that we do prepend regardless of RT_HAS_HEADER flag. 369 * This is done because BPF code shifts m_data pointer 370 * to the end of ethernet header prior to calling if_output(). 371 */ 372 M_PREPEND(m, hlen, M_NOWAIT); 373 if (m == NULL) 374 senderr(ENOBUFS); 375 if ((pflags & RT_HAS_HEADER) == 0) { 376 eh = mtod(m, struct ether_header *); 377 memcpy(eh, phdr, hlen); 378 } 379 380 /* 381 * If a simplex interface, and the packet is being sent to our 382 * Ethernet address or a broadcast address, loopback a copy. 383 * XXX To make a simplex device behave exactly like a duplex 384 * device, we should copy in the case of sending to our own 385 * ethernet address (thus letting the original actually appear 386 * on the wire). However, we don't do that here for security 387 * reasons and compatibility with the original behavior. 388 */ 389 if ((m->m_flags & M_BCAST) && loop_copy && (ifp->if_flags & IFF_SIMPLEX) && 390 ((t = pf_find_mtag(m)) == NULL || !t->routed)) { 391 struct mbuf *n; 392 393 /* 394 * Because if_simloop() modifies the packet, we need a 395 * writable copy through m_dup() instead of a readonly 396 * one as m_copy[m] would give us. The alternative would 397 * be to modify if_simloop() to handle the readonly mbuf, 398 * but performancewise it is mostly equivalent (trading 399 * extra data copying vs. extra locking). 400 * 401 * XXX This is a local workaround. A number of less 402 * often used kernel parts suffer from the same bug. 403 * See PR kern/105943 for a proposed general solution. 404 */ 405 if ((n = m_dup(m, M_NOWAIT)) != NULL) { 406 update_mbuf_csumflags(m, n); 407 (void)if_simloop(ifp, n, dst->sa_family, hlen); 408 } else 409 if_inc_counter(ifp, IFCOUNTER_IQDROPS, 1); 410 } 411 412 /* 413 * Bridges require special output handling. 414 */ 415 if (ifp->if_bridge) { 416 BRIDGE_OUTPUT(ifp, m, error); 417 return (error); 418 } 419 420 #if defined(INET) || defined(INET6) 421 if (ifp->if_carp && 422 (error = (*carp_output_p)(ifp, m, dst))) 423 goto bad; 424 #endif 425 426 /* Handle ng_ether(4) processing, if any */ 427 if (ifp->if_l2com != NULL) { 428 KASSERT(ng_ether_output_p != NULL, 429 ("ng_ether_output_p is NULL")); 430 if ((error = (*ng_ether_output_p)(ifp, &m)) != 0) { 431 bad: if (m != NULL) 432 m_freem(m); 433 return (error); 434 } 435 if (m == NULL) 436 return (0); 437 } 438 439 /* Continue with link-layer output */ 440 return ether_output_frame(ifp, m); 441 } 442 443 static bool 444 ether_set_pcp(struct mbuf **mp, struct ifnet *ifp, uint8_t pcp) 445 { 446 struct ether_header *eh; 447 448 eh = mtod(*mp, struct ether_header *); 449 if (ntohs(eh->ether_type) == ETHERTYPE_VLAN || 450 ether_8021q_frame(mp, ifp, ifp, 0, pcp)) 451 return (true); 452 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 453 return (false); 454 } 455 456 /* 457 * Ethernet link layer output routine to send a raw frame to the device. 458 * 459 * This assumes that the 14 byte Ethernet header is present and contiguous 460 * in the first mbuf (if BRIDGE'ing). 461 */ 462 int 463 ether_output_frame(struct ifnet *ifp, struct mbuf *m) 464 { 465 uint8_t pcp; 466 467 pcp = ifp->if_pcp; 468 if (pcp != IFNET_PCP_NONE && ifp->if_type != IFT_L2VLAN && 469 !ether_set_pcp(&m, ifp, pcp)) 470 return (0); 471 472 if (PFIL_HOOKED_OUT(V_link_pfil_head)) 473 switch (pfil_run_hooks(V_link_pfil_head, &m, ifp, PFIL_OUT, 474 NULL)) { 475 case PFIL_DROPPED: 476 return (EACCES); 477 case PFIL_CONSUMED: 478 return (0); 479 } 480 481 #ifdef EXPERIMENTAL 482 #if defined(INET6) && defined(INET) 483 /* draft-ietf-6man-ipv6only-flag */ 484 /* Catch ETHERTYPE_IP, and ETHERTYPE_[REV]ARP if we are v6-only. */ 485 if ((ND_IFINFO(ifp)->flags & ND6_IFF_IPV6_ONLY_MASK) != 0) { 486 struct ether_header *eh; 487 488 eh = mtod(m, struct ether_header *); 489 switch (ntohs(eh->ether_type)) { 490 case ETHERTYPE_IP: 491 case ETHERTYPE_ARP: 492 case ETHERTYPE_REVARP: 493 m_freem(m); 494 return (EAFNOSUPPORT); 495 /* NOTREACHED */ 496 break; 497 }; 498 } 499 #endif 500 #endif 501 502 /* 503 * Queue message on interface, update output statistics if 504 * successful, and start output if interface not yet active. 505 */ 506 return ((ifp->if_transmit)(ifp, m)); 507 } 508 509 /* 510 * Process a received Ethernet packet; the packet is in the 511 * mbuf chain m with the ethernet header at the front. 512 */ 513 static void 514 ether_input_internal(struct ifnet *ifp, struct mbuf *m) 515 { 516 struct ether_header *eh; 517 u_short etype; 518 519 if ((ifp->if_flags & IFF_UP) == 0) { 520 m_freem(m); 521 return; 522 } 523 #ifdef DIAGNOSTIC 524 if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0) { 525 if_printf(ifp, "discard frame at !IFF_DRV_RUNNING\n"); 526 m_freem(m); 527 return; 528 } 529 #endif 530 if (m->m_len < ETHER_HDR_LEN) { 531 /* XXX maybe should pullup? */ 532 if_printf(ifp, "discard frame w/o leading ethernet " 533 "header (len %u pkt len %u)\n", 534 m->m_len, m->m_pkthdr.len); 535 if_inc_counter(ifp, IFCOUNTER_IERRORS, 1); 536 m_freem(m); 537 return; 538 } 539 eh = mtod(m, struct ether_header *); 540 etype = ntohs(eh->ether_type); 541 random_harvest_queue_ether(m, sizeof(*m)); 542 543 #ifdef EXPERIMENTAL 544 #if defined(INET6) && defined(INET) 545 /* draft-ietf-6man-ipv6only-flag */ 546 /* Catch ETHERTYPE_IP, and ETHERTYPE_[REV]ARP if we are v6-only. */ 547 if ((ND_IFINFO(ifp)->flags & ND6_IFF_IPV6_ONLY_MASK) != 0) { 548 549 switch (etype) { 550 case ETHERTYPE_IP: 551 case ETHERTYPE_ARP: 552 case ETHERTYPE_REVARP: 553 m_freem(m); 554 return; 555 /* NOTREACHED */ 556 break; 557 }; 558 } 559 #endif 560 #endif 561 562 CURVNET_SET_QUIET(ifp->if_vnet); 563 564 if (ETHER_IS_MULTICAST(eh->ether_dhost)) { 565 if (ETHER_IS_BROADCAST(eh->ether_dhost)) 566 m->m_flags |= M_BCAST; 567 else 568 m->m_flags |= M_MCAST; 569 if_inc_counter(ifp, IFCOUNTER_IMCASTS, 1); 570 } 571 572 #ifdef MAC 573 /* 574 * Tag the mbuf with an appropriate MAC label before any other 575 * consumers can get to it. 576 */ 577 mac_ifnet_create_mbuf(ifp, m); 578 #endif 579 580 /* 581 * Give bpf a chance at the packet. 582 */ 583 ETHER_BPF_MTAP(ifp, m); 584 585 /* 586 * If the CRC is still on the packet, trim it off. We do this once 587 * and once only in case we are re-entered. Nothing else on the 588 * Ethernet receive path expects to see the FCS. 589 */ 590 if (m->m_flags & M_HASFCS) { 591 m_adj(m, -ETHER_CRC_LEN); 592 m->m_flags &= ~M_HASFCS; 593 } 594 595 if (!(ifp->if_capenable & IFCAP_HWSTATS)) 596 if_inc_counter(ifp, IFCOUNTER_IBYTES, m->m_pkthdr.len); 597 598 /* Allow monitor mode to claim this frame, after stats are updated. */ 599 if (ifp->if_flags & IFF_MONITOR) { 600 m_freem(m); 601 CURVNET_RESTORE(); 602 return; 603 } 604 605 /* Handle input from a lagg(4) port */ 606 if (ifp->if_type == IFT_IEEE8023ADLAG) { 607 KASSERT(lagg_input_p != NULL, 608 ("%s: if_lagg not loaded!", __func__)); 609 m = (*lagg_input_p)(ifp, m); 610 if (m != NULL) 611 ifp = m->m_pkthdr.rcvif; 612 else { 613 CURVNET_RESTORE(); 614 return; 615 } 616 } 617 618 /* 619 * If the hardware did not process an 802.1Q tag, do this now, 620 * to allow 802.1P priority frames to be passed to the main input 621 * path correctly. 622 * TODO: Deal with Q-in-Q frames, but not arbitrary nesting levels. 623 */ 624 if ((m->m_flags & M_VLANTAG) == 0 && etype == ETHERTYPE_VLAN) { 625 struct ether_vlan_header *evl; 626 627 if (m->m_len < sizeof(*evl) && 628 (m = m_pullup(m, sizeof(*evl))) == NULL) { 629 #ifdef DIAGNOSTIC 630 if_printf(ifp, "cannot pullup VLAN header\n"); 631 #endif 632 if_inc_counter(ifp, IFCOUNTER_IERRORS, 1); 633 CURVNET_RESTORE(); 634 return; 635 } 636 637 evl = mtod(m, struct ether_vlan_header *); 638 m->m_pkthdr.ether_vtag = ntohs(evl->evl_tag); 639 m->m_flags |= M_VLANTAG; 640 641 bcopy((char *)evl, (char *)evl + ETHER_VLAN_ENCAP_LEN, 642 ETHER_HDR_LEN - ETHER_TYPE_LEN); 643 m_adj(m, ETHER_VLAN_ENCAP_LEN); 644 eh = mtod(m, struct ether_header *); 645 } 646 647 M_SETFIB(m, ifp->if_fib); 648 649 /* Allow ng_ether(4) to claim this frame. */ 650 if (ifp->if_l2com != NULL) { 651 KASSERT(ng_ether_input_p != NULL, 652 ("%s: ng_ether_input_p is NULL", __func__)); 653 m->m_flags &= ~M_PROMISC; 654 (*ng_ether_input_p)(ifp, &m); 655 if (m == NULL) { 656 CURVNET_RESTORE(); 657 return; 658 } 659 eh = mtod(m, struct ether_header *); 660 } 661 662 /* 663 * Allow if_bridge(4) to claim this frame. 664 * The BRIDGE_INPUT() macro will update ifp if the bridge changed it 665 * and the frame should be delivered locally. 666 */ 667 if (ifp->if_bridge != NULL) { 668 m->m_flags &= ~M_PROMISC; 669 BRIDGE_INPUT(ifp, m); 670 if (m == NULL) { 671 CURVNET_RESTORE(); 672 return; 673 } 674 eh = mtod(m, struct ether_header *); 675 } 676 677 #if defined(INET) || defined(INET6) 678 /* 679 * Clear M_PROMISC on frame so that carp(4) will see it when the 680 * mbuf flows up to Layer 3. 681 * FreeBSD's implementation of carp(4) uses the inprotosw 682 * to dispatch IPPROTO_CARP. carp(4) also allocates its own 683 * Ethernet addresses of the form 00:00:5e:00:01:xx, which 684 * is outside the scope of the M_PROMISC test below. 685 * TODO: Maintain a hash table of ethernet addresses other than 686 * ether_dhost which may be active on this ifp. 687 */ 688 if (ifp->if_carp && (*carp_forus_p)(ifp, eh->ether_dhost)) { 689 m->m_flags &= ~M_PROMISC; 690 } else 691 #endif 692 { 693 /* 694 * If the frame received was not for our MAC address, set the 695 * M_PROMISC flag on the mbuf chain. The frame may need to 696 * be seen by the rest of the Ethernet input path in case of 697 * re-entry (e.g. bridge, vlan, netgraph) but should not be 698 * seen by upper protocol layers. 699 */ 700 if (!ETHER_IS_MULTICAST(eh->ether_dhost) && 701 bcmp(IF_LLADDR(ifp), eh->ether_dhost, ETHER_ADDR_LEN) != 0) 702 m->m_flags |= M_PROMISC; 703 } 704 705 ether_demux(ifp, m); 706 CURVNET_RESTORE(); 707 } 708 709 /* 710 * Ethernet input dispatch; by default, direct dispatch here regardless of 711 * global configuration. However, if RSS is enabled, hook up RSS affinity 712 * so that when deferred or hybrid dispatch is enabled, we can redistribute 713 * load based on RSS. 714 * 715 * XXXRW: Would be nice if the ifnet passed up a flag indicating whether or 716 * not it had already done work distribution via multi-queue. Then we could 717 * direct dispatch in the event load balancing was already complete and 718 * handle the case of interfaces with different capabilities better. 719 * 720 * XXXRW: Sort of want an M_DISTRIBUTED flag to avoid multiple distributions 721 * at multiple layers? 722 * 723 * XXXRW: For now, enable all this only if RSS is compiled in, although it 724 * works fine without RSS. Need to characterise the performance overhead 725 * of the detour through the netisr code in the event the result is always 726 * direct dispatch. 727 */ 728 static void 729 ether_nh_input(struct mbuf *m) 730 { 731 732 M_ASSERTPKTHDR(m); 733 KASSERT(m->m_pkthdr.rcvif != NULL, 734 ("%s: NULL interface pointer", __func__)); 735 ether_input_internal(m->m_pkthdr.rcvif, m); 736 } 737 738 static struct netisr_handler ether_nh = { 739 .nh_name = "ether", 740 .nh_handler = ether_nh_input, 741 .nh_proto = NETISR_ETHER, 742 #ifdef RSS 743 .nh_policy = NETISR_POLICY_CPU, 744 .nh_dispatch = NETISR_DISPATCH_DIRECT, 745 .nh_m2cpuid = rss_m2cpuid, 746 #else 747 .nh_policy = NETISR_POLICY_SOURCE, 748 .nh_dispatch = NETISR_DISPATCH_DIRECT, 749 #endif 750 }; 751 752 static void 753 ether_init(__unused void *arg) 754 { 755 756 netisr_register(ðer_nh); 757 } 758 SYSINIT(ether, SI_SUB_INIT_IF, SI_ORDER_ANY, ether_init, NULL); 759 760 static void 761 vnet_ether_init(__unused void *arg) 762 { 763 struct pfil_head_args args; 764 765 args.pa_version = PFIL_VERSION; 766 args.pa_flags = PFIL_IN | PFIL_OUT; 767 args.pa_type = PFIL_TYPE_ETHERNET; 768 args.pa_headname = PFIL_ETHER_NAME; 769 V_link_pfil_head = pfil_head_register(&args); 770 771 #ifdef VIMAGE 772 netisr_register_vnet(ðer_nh); 773 #endif 774 } 775 VNET_SYSINIT(vnet_ether_init, SI_SUB_PROTO_IF, SI_ORDER_ANY, 776 vnet_ether_init, NULL); 777 778 #ifdef VIMAGE 779 static void 780 vnet_ether_pfil_destroy(__unused void *arg) 781 { 782 783 pfil_head_unregister(V_link_pfil_head); 784 } 785 VNET_SYSUNINIT(vnet_ether_pfil_uninit, SI_SUB_PROTO_PFIL, SI_ORDER_ANY, 786 vnet_ether_pfil_destroy, NULL); 787 788 static void 789 vnet_ether_destroy(__unused void *arg) 790 { 791 792 netisr_unregister_vnet(ðer_nh); 793 } 794 VNET_SYSUNINIT(vnet_ether_uninit, SI_SUB_PROTO_IF, SI_ORDER_ANY, 795 vnet_ether_destroy, NULL); 796 #endif 797 798 799 800 static void 801 ether_input(struct ifnet *ifp, struct mbuf *m) 802 { 803 struct epoch_tracker et; 804 struct mbuf *mn; 805 806 /* 807 * The drivers are allowed to pass in a chain of packets linked with 808 * m_nextpkt. We split them up into separate packets here and pass 809 * them up. This allows the drivers to amortize the receive lock. 810 */ 811 CURVNET_SET_QUIET(ifp->if_vnet); 812 if (__predict_false(ifp->if_flags & IFF_NEEDSEPOCH)) 813 NET_EPOCH_ENTER(et); 814 while (m) { 815 mn = m->m_nextpkt; 816 m->m_nextpkt = NULL; 817 818 /* 819 * We will rely on rcvif being set properly in the deferred 820 * context, so assert it is correct here. 821 */ 822 MPASS((m->m_pkthdr.csum_flags & CSUM_SND_TAG) == 0); 823 KASSERT(m->m_pkthdr.rcvif == ifp, ("%s: ifnet mismatch m %p " 824 "rcvif %p ifp %p", __func__, m, m->m_pkthdr.rcvif, ifp)); 825 netisr_dispatch(NETISR_ETHER, m); 826 m = mn; 827 } 828 if (__predict_false(ifp->if_flags & IFF_NEEDSEPOCH)) 829 NET_EPOCH_EXIT(et); 830 CURVNET_RESTORE(); 831 } 832 833 /* 834 * Upper layer processing for a received Ethernet packet. 835 */ 836 void 837 ether_demux(struct ifnet *ifp, struct mbuf *m) 838 { 839 struct ether_header *eh; 840 int i, isr; 841 u_short ether_type; 842 843 NET_EPOCH_ASSERT(); 844 KASSERT(ifp != NULL, ("%s: NULL interface pointer", __func__)); 845 846 /* Do not grab PROMISC frames in case we are re-entered. */ 847 if (PFIL_HOOKED_IN(V_link_pfil_head) && !(m->m_flags & M_PROMISC)) { 848 i = pfil_run_hooks(V_link_pfil_head, &m, ifp, PFIL_IN, NULL); 849 if (i != 0 || m == NULL) 850 return; 851 } 852 853 eh = mtod(m, struct ether_header *); 854 ether_type = ntohs(eh->ether_type); 855 856 /* 857 * If this frame has a VLAN tag other than 0, call vlan_input() 858 * if its module is loaded. Otherwise, drop. 859 */ 860 if ((m->m_flags & M_VLANTAG) && 861 EVL_VLANOFTAG(m->m_pkthdr.ether_vtag) != 0) { 862 if (ifp->if_vlantrunk == NULL) { 863 if_inc_counter(ifp, IFCOUNTER_NOPROTO, 1); 864 m_freem(m); 865 return; 866 } 867 KASSERT(vlan_input_p != NULL,("%s: VLAN not loaded!", 868 __func__)); 869 /* Clear before possibly re-entering ether_input(). */ 870 m->m_flags &= ~M_PROMISC; 871 (*vlan_input_p)(ifp, m); 872 return; 873 } 874 875 /* 876 * Pass promiscuously received frames to the upper layer if the user 877 * requested this by setting IFF_PPROMISC. Otherwise, drop them. 878 */ 879 if ((ifp->if_flags & IFF_PPROMISC) == 0 && (m->m_flags & M_PROMISC)) { 880 m_freem(m); 881 return; 882 } 883 884 /* 885 * Reset layer specific mbuf flags to avoid confusing upper layers. 886 * Strip off Ethernet header. 887 */ 888 m->m_flags &= ~M_VLANTAG; 889 m_clrprotoflags(m); 890 m_adj(m, ETHER_HDR_LEN); 891 892 /* 893 * Dispatch frame to upper layer. 894 */ 895 switch (ether_type) { 896 #ifdef INET 897 case ETHERTYPE_IP: 898 isr = NETISR_IP; 899 break; 900 901 case ETHERTYPE_ARP: 902 if (ifp->if_flags & IFF_NOARP) { 903 /* Discard packet if ARP is disabled on interface */ 904 m_freem(m); 905 return; 906 } 907 isr = NETISR_ARP; 908 break; 909 #endif 910 #ifdef INET6 911 case ETHERTYPE_IPV6: 912 isr = NETISR_IPV6; 913 break; 914 #endif 915 default: 916 goto discard; 917 } 918 netisr_dispatch(isr, m); 919 return; 920 921 discard: 922 /* 923 * Packet is to be discarded. If netgraph is present, 924 * hand the packet to it for last chance processing; 925 * otherwise dispose of it. 926 */ 927 if (ifp->if_l2com != NULL) { 928 KASSERT(ng_ether_input_orphan_p != NULL, 929 ("ng_ether_input_orphan_p is NULL")); 930 /* 931 * Put back the ethernet header so netgraph has a 932 * consistent view of inbound packets. 933 */ 934 M_PREPEND(m, ETHER_HDR_LEN, M_NOWAIT); 935 (*ng_ether_input_orphan_p)(ifp, m); 936 return; 937 } 938 m_freem(m); 939 } 940 941 /* 942 * Convert Ethernet address to printable (loggable) representation. 943 * This routine is for compatibility; it's better to just use 944 * 945 * printf("%6D", <pointer to address>, ":"); 946 * 947 * since there's no static buffer involved. 948 */ 949 char * 950 ether_sprintf(const u_char *ap) 951 { 952 static char etherbuf[18]; 953 snprintf(etherbuf, sizeof (etherbuf), "%6D", ap, ":"); 954 return (etherbuf); 955 } 956 957 /* 958 * Perform common duties while attaching to interface list 959 */ 960 void 961 ether_ifattach(struct ifnet *ifp, const u_int8_t *lla) 962 { 963 int i; 964 struct ifaddr *ifa; 965 struct sockaddr_dl *sdl; 966 967 ifp->if_addrlen = ETHER_ADDR_LEN; 968 ifp->if_hdrlen = ETHER_HDR_LEN; 969 if_attach(ifp); 970 ifp->if_mtu = ETHERMTU; 971 ifp->if_output = ether_output; 972 ifp->if_input = ether_input; 973 ifp->if_resolvemulti = ether_resolvemulti; 974 ifp->if_requestencap = ether_requestencap; 975 #ifdef VIMAGE 976 ifp->if_reassign = ether_reassign; 977 #endif 978 if (ifp->if_baudrate == 0) 979 ifp->if_baudrate = IF_Mbps(10); /* just a default */ 980 ifp->if_broadcastaddr = etherbroadcastaddr; 981 982 ifa = ifp->if_addr; 983 KASSERT(ifa != NULL, ("%s: no lladdr!\n", __func__)); 984 sdl = (struct sockaddr_dl *)ifa->ifa_addr; 985 sdl->sdl_type = IFT_ETHER; 986 sdl->sdl_alen = ifp->if_addrlen; 987 bcopy(lla, LLADDR(sdl), ifp->if_addrlen); 988 989 if (ifp->if_hw_addr != NULL) 990 bcopy(lla, ifp->if_hw_addr, ifp->if_addrlen); 991 992 bpfattach(ifp, DLT_EN10MB, ETHER_HDR_LEN); 993 if (ng_ether_attach_p != NULL) 994 (*ng_ether_attach_p)(ifp); 995 996 /* Announce Ethernet MAC address if non-zero. */ 997 for (i = 0; i < ifp->if_addrlen; i++) 998 if (lla[i] != 0) 999 break; 1000 if (i != ifp->if_addrlen) 1001 if_printf(ifp, "Ethernet address: %6D\n", lla, ":"); 1002 1003 uuid_ether_add(LLADDR(sdl)); 1004 1005 /* Add necessary bits are setup; announce it now. */ 1006 EVENTHANDLER_INVOKE(ether_ifattach_event, ifp); 1007 if (IS_DEFAULT_VNET(curvnet)) 1008 devctl_notify("ETHERNET", ifp->if_xname, "IFATTACH", NULL); 1009 } 1010 1011 /* 1012 * Perform common duties while detaching an Ethernet interface 1013 */ 1014 void 1015 ether_ifdetach(struct ifnet *ifp) 1016 { 1017 struct sockaddr_dl *sdl; 1018 1019 sdl = (struct sockaddr_dl *)(ifp->if_addr->ifa_addr); 1020 uuid_ether_del(LLADDR(sdl)); 1021 1022 if (ifp->if_l2com != NULL) { 1023 KASSERT(ng_ether_detach_p != NULL, 1024 ("ng_ether_detach_p is NULL")); 1025 (*ng_ether_detach_p)(ifp); 1026 } 1027 1028 bpfdetach(ifp); 1029 if_detach(ifp); 1030 } 1031 1032 #ifdef VIMAGE 1033 void 1034 ether_reassign(struct ifnet *ifp, struct vnet *new_vnet, char *unused __unused) 1035 { 1036 1037 if (ifp->if_l2com != NULL) { 1038 KASSERT(ng_ether_detach_p != NULL, 1039 ("ng_ether_detach_p is NULL")); 1040 (*ng_ether_detach_p)(ifp); 1041 } 1042 1043 if (ng_ether_attach_p != NULL) { 1044 CURVNET_SET_QUIET(new_vnet); 1045 (*ng_ether_attach_p)(ifp); 1046 CURVNET_RESTORE(); 1047 } 1048 } 1049 #endif 1050 1051 SYSCTL_DECL(_net_link); 1052 SYSCTL_NODE(_net_link, IFT_ETHER, ether, CTLFLAG_RW, 0, "Ethernet"); 1053 1054 #if 0 1055 /* 1056 * This is for reference. We have a table-driven version 1057 * of the little-endian crc32 generator, which is faster 1058 * than the double-loop. 1059 */ 1060 uint32_t 1061 ether_crc32_le(const uint8_t *buf, size_t len) 1062 { 1063 size_t i; 1064 uint32_t crc; 1065 int bit; 1066 uint8_t data; 1067 1068 crc = 0xffffffff; /* initial value */ 1069 1070 for (i = 0; i < len; i++) { 1071 for (data = *buf++, bit = 0; bit < 8; bit++, data >>= 1) { 1072 carry = (crc ^ data) & 1; 1073 crc >>= 1; 1074 if (carry) 1075 crc = (crc ^ ETHER_CRC_POLY_LE); 1076 } 1077 } 1078 1079 return (crc); 1080 } 1081 #else 1082 uint32_t 1083 ether_crc32_le(const uint8_t *buf, size_t len) 1084 { 1085 static const uint32_t crctab[] = { 1086 0x00000000, 0x1db71064, 0x3b6e20c8, 0x26d930ac, 1087 0x76dc4190, 0x6b6b51f4, 0x4db26158, 0x5005713c, 1088 0xedb88320, 0xf00f9344, 0xd6d6a3e8, 0xcb61b38c, 1089 0x9b64c2b0, 0x86d3d2d4, 0xa00ae278, 0xbdbdf21c 1090 }; 1091 size_t i; 1092 uint32_t crc; 1093 1094 crc = 0xffffffff; /* initial value */ 1095 1096 for (i = 0; i < len; i++) { 1097 crc ^= buf[i]; 1098 crc = (crc >> 4) ^ crctab[crc & 0xf]; 1099 crc = (crc >> 4) ^ crctab[crc & 0xf]; 1100 } 1101 1102 return (crc); 1103 } 1104 #endif 1105 1106 uint32_t 1107 ether_crc32_be(const uint8_t *buf, size_t len) 1108 { 1109 size_t i; 1110 uint32_t crc, carry; 1111 int bit; 1112 uint8_t data; 1113 1114 crc = 0xffffffff; /* initial value */ 1115 1116 for (i = 0; i < len; i++) { 1117 for (data = *buf++, bit = 0; bit < 8; bit++, data >>= 1) { 1118 carry = ((crc & 0x80000000) ? 1 : 0) ^ (data & 0x01); 1119 crc <<= 1; 1120 if (carry) 1121 crc = (crc ^ ETHER_CRC_POLY_BE) | carry; 1122 } 1123 } 1124 1125 return (crc); 1126 } 1127 1128 int 1129 ether_ioctl(struct ifnet *ifp, u_long command, caddr_t data) 1130 { 1131 struct ifaddr *ifa = (struct ifaddr *) data; 1132 struct ifreq *ifr = (struct ifreq *) data; 1133 int error = 0; 1134 1135 switch (command) { 1136 case SIOCSIFADDR: 1137 ifp->if_flags |= IFF_UP; 1138 1139 switch (ifa->ifa_addr->sa_family) { 1140 #ifdef INET 1141 case AF_INET: 1142 ifp->if_init(ifp->if_softc); /* before arpwhohas */ 1143 arp_ifinit(ifp, ifa); 1144 break; 1145 #endif 1146 default: 1147 ifp->if_init(ifp->if_softc); 1148 break; 1149 } 1150 break; 1151 1152 case SIOCGIFADDR: 1153 bcopy(IF_LLADDR(ifp), &ifr->ifr_addr.sa_data[0], 1154 ETHER_ADDR_LEN); 1155 break; 1156 1157 case SIOCSIFMTU: 1158 /* 1159 * Set the interface MTU. 1160 */ 1161 if (ifr->ifr_mtu > ETHERMTU) { 1162 error = EINVAL; 1163 } else { 1164 ifp->if_mtu = ifr->ifr_mtu; 1165 } 1166 break; 1167 1168 case SIOCSLANPCP: 1169 error = priv_check(curthread, PRIV_NET_SETLANPCP); 1170 if (error != 0) 1171 break; 1172 if (ifr->ifr_lan_pcp > 7 && 1173 ifr->ifr_lan_pcp != IFNET_PCP_NONE) { 1174 error = EINVAL; 1175 } else { 1176 ifp->if_pcp = ifr->ifr_lan_pcp; 1177 /* broadcast event about PCP change */ 1178 EVENTHANDLER_INVOKE(ifnet_event, ifp, IFNET_EVENT_PCP); 1179 } 1180 break; 1181 1182 case SIOCGLANPCP: 1183 ifr->ifr_lan_pcp = ifp->if_pcp; 1184 break; 1185 1186 default: 1187 error = EINVAL; /* XXX netbsd has ENOTTY??? */ 1188 break; 1189 } 1190 return (error); 1191 } 1192 1193 static int 1194 ether_resolvemulti(struct ifnet *ifp, struct sockaddr **llsa, 1195 struct sockaddr *sa) 1196 { 1197 struct sockaddr_dl *sdl; 1198 #ifdef INET 1199 struct sockaddr_in *sin; 1200 #endif 1201 #ifdef INET6 1202 struct sockaddr_in6 *sin6; 1203 #endif 1204 u_char *e_addr; 1205 1206 switch(sa->sa_family) { 1207 case AF_LINK: 1208 /* 1209 * No mapping needed. Just check that it's a valid MC address. 1210 */ 1211 sdl = (struct sockaddr_dl *)sa; 1212 e_addr = LLADDR(sdl); 1213 if (!ETHER_IS_MULTICAST(e_addr)) 1214 return EADDRNOTAVAIL; 1215 *llsa = NULL; 1216 return 0; 1217 1218 #ifdef INET 1219 case AF_INET: 1220 sin = (struct sockaddr_in *)sa; 1221 if (!IN_MULTICAST(ntohl(sin->sin_addr.s_addr))) 1222 return EADDRNOTAVAIL; 1223 sdl = link_init_sdl(ifp, *llsa, IFT_ETHER); 1224 sdl->sdl_alen = ETHER_ADDR_LEN; 1225 e_addr = LLADDR(sdl); 1226 ETHER_MAP_IP_MULTICAST(&sin->sin_addr, e_addr); 1227 *llsa = (struct sockaddr *)sdl; 1228 return 0; 1229 #endif 1230 #ifdef INET6 1231 case AF_INET6: 1232 sin6 = (struct sockaddr_in6 *)sa; 1233 if (IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr)) { 1234 /* 1235 * An IP6 address of 0 means listen to all 1236 * of the Ethernet multicast address used for IP6. 1237 * (This is used for multicast routers.) 1238 */ 1239 ifp->if_flags |= IFF_ALLMULTI; 1240 *llsa = NULL; 1241 return 0; 1242 } 1243 if (!IN6_IS_ADDR_MULTICAST(&sin6->sin6_addr)) 1244 return EADDRNOTAVAIL; 1245 sdl = link_init_sdl(ifp, *llsa, IFT_ETHER); 1246 sdl->sdl_alen = ETHER_ADDR_LEN; 1247 e_addr = LLADDR(sdl); 1248 ETHER_MAP_IPV6_MULTICAST(&sin6->sin6_addr, e_addr); 1249 *llsa = (struct sockaddr *)sdl; 1250 return 0; 1251 #endif 1252 1253 default: 1254 /* 1255 * Well, the text isn't quite right, but it's the name 1256 * that counts... 1257 */ 1258 return EAFNOSUPPORT; 1259 } 1260 } 1261 1262 static moduledata_t ether_mod = { 1263 .name = "ether", 1264 }; 1265 1266 void 1267 ether_vlan_mtap(struct bpf_if *bp, struct mbuf *m, void *data, u_int dlen) 1268 { 1269 struct ether_vlan_header vlan; 1270 struct mbuf mv, mb; 1271 1272 KASSERT((m->m_flags & M_VLANTAG) != 0, 1273 ("%s: vlan information not present", __func__)); 1274 KASSERT(m->m_len >= sizeof(struct ether_header), 1275 ("%s: mbuf not large enough for header", __func__)); 1276 bcopy(mtod(m, char *), &vlan, sizeof(struct ether_header)); 1277 vlan.evl_proto = vlan.evl_encap_proto; 1278 vlan.evl_encap_proto = htons(ETHERTYPE_VLAN); 1279 vlan.evl_tag = htons(m->m_pkthdr.ether_vtag); 1280 m->m_len -= sizeof(struct ether_header); 1281 m->m_data += sizeof(struct ether_header); 1282 /* 1283 * If a data link has been supplied by the caller, then we will need to 1284 * re-create a stack allocated mbuf chain with the following structure: 1285 * 1286 * (1) mbuf #1 will contain the supplied data link 1287 * (2) mbuf #2 will contain the vlan header 1288 * (3) mbuf #3 will contain the original mbuf's packet data 1289 * 1290 * Otherwise, submit the packet and vlan header via bpf_mtap2(). 1291 */ 1292 if (data != NULL) { 1293 mv.m_next = m; 1294 mv.m_data = (caddr_t)&vlan; 1295 mv.m_len = sizeof(vlan); 1296 mb.m_next = &mv; 1297 mb.m_data = data; 1298 mb.m_len = dlen; 1299 bpf_mtap(bp, &mb); 1300 } else 1301 bpf_mtap2(bp, &vlan, sizeof(vlan), m); 1302 m->m_len += sizeof(struct ether_header); 1303 m->m_data -= sizeof(struct ether_header); 1304 } 1305 1306 struct mbuf * 1307 ether_vlanencap(struct mbuf *m, uint16_t tag) 1308 { 1309 struct ether_vlan_header *evl; 1310 1311 M_PREPEND(m, ETHER_VLAN_ENCAP_LEN, M_NOWAIT); 1312 if (m == NULL) 1313 return (NULL); 1314 /* M_PREPEND takes care of m_len, m_pkthdr.len for us */ 1315 1316 if (m->m_len < sizeof(*evl)) { 1317 m = m_pullup(m, sizeof(*evl)); 1318 if (m == NULL) 1319 return (NULL); 1320 } 1321 1322 /* 1323 * Transform the Ethernet header into an Ethernet header 1324 * with 802.1Q encapsulation. 1325 */ 1326 evl = mtod(m, struct ether_vlan_header *); 1327 bcopy((char *)evl + ETHER_VLAN_ENCAP_LEN, 1328 (char *)evl, ETHER_HDR_LEN - ETHER_TYPE_LEN); 1329 evl->evl_encap_proto = htons(ETHERTYPE_VLAN); 1330 evl->evl_tag = htons(tag); 1331 return (m); 1332 } 1333 1334 static SYSCTL_NODE(_net_link, IFT_L2VLAN, vlan, CTLFLAG_RW, 0, 1335 "IEEE 802.1Q VLAN"); 1336 static SYSCTL_NODE(_net_link_vlan, PF_LINK, link, CTLFLAG_RW, 0, 1337 "for consistency"); 1338 1339 VNET_DEFINE_STATIC(int, soft_pad); 1340 #define V_soft_pad VNET(soft_pad) 1341 SYSCTL_INT(_net_link_vlan, OID_AUTO, soft_pad, CTLFLAG_RW | CTLFLAG_VNET, 1342 &VNET_NAME(soft_pad), 0, 1343 "pad short frames before tagging"); 1344 1345 /* 1346 * For now, make preserving PCP via an mbuf tag optional, as it increases 1347 * per-packet memory allocations and frees. In the future, it would be 1348 * preferable to reuse ether_vtag for this, or similar. 1349 */ 1350 int vlan_mtag_pcp = 0; 1351 SYSCTL_INT(_net_link_vlan, OID_AUTO, mtag_pcp, CTLFLAG_RW, 1352 &vlan_mtag_pcp, 0, 1353 "Retain VLAN PCP information as packets are passed up the stack"); 1354 1355 bool 1356 ether_8021q_frame(struct mbuf **mp, struct ifnet *ife, struct ifnet *p, 1357 uint16_t vid, uint8_t pcp) 1358 { 1359 struct m_tag *mtag; 1360 int n; 1361 uint16_t tag; 1362 static const char pad[8]; /* just zeros */ 1363 1364 /* 1365 * Pad the frame to the minimum size allowed if told to. 1366 * This option is in accord with IEEE Std 802.1Q, 2003 Ed., 1367 * paragraph C.4.4.3.b. It can help to work around buggy 1368 * bridges that violate paragraph C.4.4.3.a from the same 1369 * document, i.e., fail to pad short frames after untagging. 1370 * E.g., a tagged frame 66 bytes long (incl. FCS) is OK, but 1371 * untagging it will produce a 62-byte frame, which is a runt 1372 * and requires padding. There are VLAN-enabled network 1373 * devices that just discard such runts instead or mishandle 1374 * them somehow. 1375 */ 1376 if (V_soft_pad && p->if_type == IFT_ETHER) { 1377 for (n = ETHERMIN + ETHER_HDR_LEN - (*mp)->m_pkthdr.len; 1378 n > 0; n -= sizeof(pad)) { 1379 if (!m_append(*mp, min(n, sizeof(pad)), pad)) 1380 break; 1381 } 1382 if (n > 0) { 1383 m_freem(*mp); 1384 *mp = NULL; 1385 if_printf(ife, "cannot pad short frame"); 1386 return (false); 1387 } 1388 } 1389 1390 /* 1391 * If underlying interface can do VLAN tag insertion itself, 1392 * just pass the packet along. However, we need some way to 1393 * tell the interface where the packet came from so that it 1394 * knows how to find the VLAN tag to use, so we attach a 1395 * packet tag that holds it. 1396 */ 1397 if (vlan_mtag_pcp && (mtag = m_tag_locate(*mp, MTAG_8021Q, 1398 MTAG_8021Q_PCP_OUT, NULL)) != NULL) 1399 tag = EVL_MAKETAG(vid, *(uint8_t *)(mtag + 1), 0); 1400 else 1401 tag = EVL_MAKETAG(vid, pcp, 0); 1402 if (p->if_capenable & IFCAP_VLAN_HWTAGGING) { 1403 (*mp)->m_pkthdr.ether_vtag = tag; 1404 (*mp)->m_flags |= M_VLANTAG; 1405 } else { 1406 *mp = ether_vlanencap(*mp, tag); 1407 if (*mp == NULL) { 1408 if_printf(ife, "unable to prepend 802.1Q header"); 1409 return (false); 1410 } 1411 } 1412 return (true); 1413 } 1414 1415 /* 1416 * Allocate an address from the FreeBSD Foundation OUI. This uses a 1417 * cryptographic hash function on the containing jail's UUID and the interface 1418 * name to attempt to provide a unique but stable address. Pseudo-interfaces 1419 * which require a MAC address should use this function to allocate 1420 * non-locally-administered addresses. 1421 */ 1422 void 1423 ether_gen_addr(struct ifnet *ifp, struct ether_addr *hwaddr) 1424 { 1425 #define ETHER_GEN_ADDR_BUFSIZ HOSTUUIDLEN + IFNAMSIZ + 2 1426 SHA1_CTX ctx; 1427 char buf[ETHER_GEN_ADDR_BUFSIZ]; 1428 char uuid[HOSTUUIDLEN + 1]; 1429 uint64_t addr; 1430 int i, sz; 1431 char digest[SHA1_RESULTLEN]; 1432 1433 getcredhostuuid(curthread->td_ucred, uuid, sizeof(uuid)); 1434 sz = snprintf(buf, ETHER_GEN_ADDR_BUFSIZ, "%s-%s", uuid, ifp->if_xname); 1435 SHA1Init(&ctx); 1436 SHA1Update(&ctx, buf, sz); 1437 SHA1Final(digest, &ctx); 1438 1439 addr = ((digest[0] << 16) | (digest[1] << 8) | digest[2]) & 1440 OUI_FREEBSD_GENERATED_MASK; 1441 addr = OUI_FREEBSD(addr); 1442 for (i = 0; i < ETHER_ADDR_LEN; ++i) { 1443 hwaddr->octet[i] = addr >> ((ETHER_ADDR_LEN - i - 1) * 8) & 1444 0xFF; 1445 } 1446 } 1447 1448 DECLARE_MODULE(ether, ether_mod, SI_SUB_INIT_IF, SI_ORDER_ANY); 1449 MODULE_VERSION(ether, 1); 1450