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 */ 33 34 #include "opt_inet.h" 35 #include "opt_inet6.h" 36 #include "opt_netgraph.h" 37 #include "opt_mbuf_profiling.h" 38 #include "opt_rss.h" 39 40 #include <sys/param.h> 41 #include <sys/systm.h> 42 #include <sys/devctl.h> 43 #include <sys/eventhandler.h> 44 #include <sys/jail.h> 45 #include <sys/kernel.h> 46 #include <sys/lock.h> 47 #include <sys/malloc.h> 48 #include <sys/mbuf.h> 49 #include <sys/module.h> 50 #include <sys/msan.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 #ifdef KDB 59 #include <sys/kdb.h> 60 #endif 61 62 #include <net/ieee_oui.h> 63 #include <net/if.h> 64 #include <net/if_var.h> 65 #include <net/if_private.h> 66 #include <net/if_arp.h> 67 #include <net/netisr.h> 68 #include <net/route.h> 69 #include <net/if_llc.h> 70 #include <net/if_dl.h> 71 #include <net/if_types.h> 72 #include <net/bpf.h> 73 #include <net/ethernet.h> 74 #include <net/if_bridgevar.h> 75 #include <net/if_vlan_var.h> 76 #include <net/if_llatbl.h> 77 #include <net/pfil.h> 78 #include <net/rss_config.h> 79 #include <net/vnet.h> 80 81 #include <netpfil/pf/pf_mtag.h> 82 83 #if defined(INET) || defined(INET6) 84 #include <netinet/in.h> 85 #include <netinet/in_var.h> 86 #include <netinet/if_ether.h> 87 #include <netinet/ip_carp.h> 88 #include <netinet/ip_var.h> 89 #endif 90 #ifdef INET6 91 #include <netinet6/nd6.h> 92 #endif 93 #include <security/mac/mac_framework.h> 94 95 #include <crypto/sha1.h> 96 97 #ifdef CTASSERT 98 CTASSERT(sizeof (struct ether_header) == ETHER_ADDR_LEN * 2 + 2); 99 CTASSERT(sizeof (struct ether_addr) == ETHER_ADDR_LEN); 100 #endif 101 102 VNET_DEFINE(pfil_head_t, link_pfil_head); /* Packet filter hooks */ 103 104 /* netgraph node hooks for ng_ether(4) */ 105 void (*ng_ether_input_p)(struct ifnet *ifp, struct mbuf **mp); 106 void (*ng_ether_input_orphan_p)(struct ifnet *ifp, struct mbuf *m); 107 int (*ng_ether_output_p)(struct ifnet *ifp, struct mbuf **mp); 108 void (*ng_ether_attach_p)(struct ifnet *ifp); 109 void (*ng_ether_detach_p)(struct ifnet *ifp); 110 111 void (*vlan_input_p)(struct ifnet *, struct mbuf *); 112 113 /* if_bridge(4) support */ 114 void (*bridge_dn_p)(struct mbuf *, struct ifnet *); 115 116 /* if_lagg(4) support */ 117 struct mbuf *(*lagg_input_ethernet_p)(struct ifnet *, struct mbuf *); 118 119 static const u_char etherbroadcastaddr[ETHER_ADDR_LEN] = 120 { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff }; 121 122 static int ether_resolvemulti(struct ifnet *, struct sockaddr **, 123 struct sockaddr *); 124 static int ether_requestencap(struct ifnet *, struct if_encap_req *); 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 static int 204 ether_resolve_addr(struct ifnet *ifp, struct mbuf *m, 205 const struct sockaddr *dst, struct route *ro, u_char *phdr, 206 uint32_t *pflags, struct llentry **plle) 207 { 208 uint32_t lleflags = 0; 209 int error = 0; 210 #if defined(INET) || defined(INET6) 211 struct ether_header *eh = (struct ether_header *)phdr; 212 uint16_t etype; 213 #endif 214 215 if (plle) 216 *plle = NULL; 217 218 switch (dst->sa_family) { 219 #ifdef INET 220 case AF_INET: 221 if ((m->m_flags & (M_BCAST | M_MCAST)) == 0) 222 error = arpresolve(ifp, 0, m, dst, phdr, &lleflags, 223 plle); 224 else { 225 if (m->m_flags & M_BCAST) 226 memcpy(eh->ether_dhost, ifp->if_broadcastaddr, 227 ETHER_ADDR_LEN); 228 else { 229 const struct in_addr *a; 230 a = &(((const struct sockaddr_in *)dst)->sin_addr); 231 ETHER_MAP_IP_MULTICAST(a, eh->ether_dhost); 232 } 233 etype = htons(ETHERTYPE_IP); 234 memcpy(&eh->ether_type, &etype, sizeof(etype)); 235 memcpy(eh->ether_shost, IF_LLADDR(ifp), ETHER_ADDR_LEN); 236 } 237 break; 238 #endif 239 #ifdef INET6 240 case AF_INET6: 241 if ((m->m_flags & M_MCAST) == 0) { 242 int af = RO_GET_FAMILY(ro, dst); 243 error = nd6_resolve(ifp, LLE_SF(af, 0), m, dst, phdr, 244 &lleflags, plle); 245 } else { 246 const struct in6_addr *a6; 247 a6 = &(((const struct sockaddr_in6 *)dst)->sin6_addr); 248 ETHER_MAP_IPV6_MULTICAST(a6, eh->ether_dhost); 249 etype = htons(ETHERTYPE_IPV6); 250 memcpy(&eh->ether_type, &etype, sizeof(etype)); 251 memcpy(eh->ether_shost, IF_LLADDR(ifp), ETHER_ADDR_LEN); 252 } 253 break; 254 #endif 255 default: 256 if_printf(ifp, "can't handle af%d\n", dst->sa_family); 257 if (m != NULL) 258 m_freem(m); 259 return (EAFNOSUPPORT); 260 } 261 262 if (error == EHOSTDOWN) { 263 if (ro != NULL && (ro->ro_flags & RT_HAS_GW) != 0) 264 error = EHOSTUNREACH; 265 } 266 267 if (error != 0) 268 return (error); 269 270 *pflags = RT_MAY_LOOP; 271 if (lleflags & LLE_IFADDR) 272 *pflags |= RT_L2_ME; 273 274 return (0); 275 } 276 277 /* 278 * Ethernet output routine. 279 * Encapsulate a packet of type family for the local net. 280 * Use trailer local net encapsulation if enough data in first 281 * packet leaves a multiple of 512 bytes of data in remainder. 282 */ 283 int 284 ether_output(struct ifnet *ifp, struct mbuf *m, 285 const struct sockaddr *dst, struct route *ro) 286 { 287 int error = 0; 288 char linkhdr[ETHER_HDR_LEN], *phdr; 289 struct ether_header *eh; 290 struct pf_mtag *t; 291 bool loop_copy; 292 int hlen; /* link layer header length */ 293 uint32_t pflags; 294 struct llentry *lle = NULL; 295 int addref = 0; 296 297 phdr = NULL; 298 pflags = 0; 299 if (ro != NULL) { 300 /* XXX BPF uses ro_prepend */ 301 if (ro->ro_prepend != NULL) { 302 phdr = ro->ro_prepend; 303 hlen = ro->ro_plen; 304 } else if (!(m->m_flags & (M_BCAST | M_MCAST))) { 305 if ((ro->ro_flags & RT_LLE_CACHE) != 0) { 306 lle = ro->ro_lle; 307 if (lle != NULL && 308 (lle->la_flags & LLE_VALID) == 0) { 309 LLE_FREE(lle); 310 lle = NULL; /* redundant */ 311 ro->ro_lle = NULL; 312 } 313 if (lle == NULL) { 314 /* if we lookup, keep cache */ 315 addref = 1; 316 } else 317 /* 318 * Notify LLE code that 319 * the entry was used 320 * by datapath. 321 */ 322 llentry_provide_feedback(lle); 323 } 324 if (lle != NULL) { 325 phdr = lle->r_linkdata; 326 hlen = lle->r_hdrlen; 327 pflags = lle->r_flags; 328 } 329 } 330 } 331 332 #ifdef MAC 333 error = mac_ifnet_check_transmit(ifp, m); 334 if (error) 335 senderr(error); 336 #endif 337 338 M_PROFILE(m); 339 if (ifp->if_flags & IFF_MONITOR) 340 senderr(ENETDOWN); 341 if (!((ifp->if_flags & IFF_UP) && 342 (ifp->if_drv_flags & IFF_DRV_RUNNING))) 343 senderr(ENETDOWN); 344 345 if (phdr == NULL) { 346 /* No prepend data supplied. Try to calculate ourselves. */ 347 phdr = linkhdr; 348 hlen = ETHER_HDR_LEN; 349 error = ether_resolve_addr(ifp, m, dst, ro, phdr, &pflags, 350 addref ? &lle : NULL); 351 if (addref && lle != NULL) 352 ro->ro_lle = lle; 353 if (error != 0) 354 return (error == EWOULDBLOCK ? 0 : error); 355 } 356 357 if ((pflags & RT_L2_ME) != 0) { 358 update_mbuf_csumflags(m, m); 359 return (if_simloop(ifp, m, RO_GET_FAMILY(ro, dst), 0)); 360 } 361 loop_copy = (pflags & RT_MAY_LOOP) != 0; 362 363 /* 364 * Add local net header. If no space in first mbuf, 365 * allocate another. 366 * 367 * Note that we do prepend regardless of RT_HAS_HEADER flag. 368 * This is done because BPF code shifts m_data pointer 369 * to the end of ethernet header prior to calling if_output(). 370 */ 371 M_PREPEND(m, hlen, M_NOWAIT); 372 if (m == NULL) 373 senderr(ENOBUFS); 374 if ((pflags & RT_HAS_HEADER) == 0) { 375 eh = mtod(m, struct ether_header *); 376 memcpy(eh, phdr, hlen); 377 } 378 379 /* 380 * If a simplex interface, and the packet is being sent to our 381 * Ethernet address or a broadcast address, loopback a copy. 382 * XXX To make a simplex device behave exactly like a duplex 383 * device, we should copy in the case of sending to our own 384 * ethernet address (thus letting the original actually appear 385 * on the wire). However, we don't do that here for security 386 * reasons and compatibility with the original behavior. 387 */ 388 if ((m->m_flags & M_BCAST) && loop_copy && (ifp->if_flags & IFF_SIMPLEX) && 389 ((t = pf_find_mtag(m)) == NULL || !t->routed)) { 390 struct mbuf *n; 391 392 /* 393 * Because if_simloop() modifies the packet, we need a 394 * writable copy through m_dup() instead of a readonly 395 * one as m_copy[m] would give us. The alternative would 396 * be to modify if_simloop() to handle the readonly mbuf, 397 * but performancewise it is mostly equivalent (trading 398 * extra data copying vs. extra locking). 399 * 400 * XXX This is a local workaround. A number of less 401 * often used kernel parts suffer from the same bug. 402 * See PR kern/105943 for a proposed general solution. 403 */ 404 if ((n = m_dup(m, M_NOWAIT)) != NULL) { 405 update_mbuf_csumflags(m, n); 406 (void)if_simloop(ifp, n, RO_GET_FAMILY(ro, dst), hlen); 407 } else 408 if_inc_counter(ifp, IFCOUNTER_IQDROPS, 1); 409 } 410 411 /* 412 * Bridges require special output handling. 413 */ 414 if (ifp->if_bridge) { 415 BRIDGE_OUTPUT(ifp, m, error); 416 return (error); 417 } 418 419 #if defined(INET) || defined(INET6) 420 if (ifp->if_carp && 421 (error = (*carp_output_p)(ifp, m, dst))) 422 goto bad; 423 #endif 424 425 /* Handle ng_ether(4) processing, if any */ 426 if (ifp->if_l2com != NULL) { 427 KASSERT(ng_ether_output_p != NULL, 428 ("ng_ether_output_p is NULL")); 429 if ((error = (*ng_ether_output_p)(ifp, &m)) != 0) { 430 bad: if (m != NULL) 431 m_freem(m); 432 return (error); 433 } 434 if (m == NULL) 435 return (0); 436 } 437 438 /* Continue with link-layer output */ 439 return ether_output_frame(ifp, m); 440 } 441 442 static bool 443 ether_set_pcp(struct mbuf **mp, struct ifnet *ifp, uint8_t pcp) 444 { 445 struct ether_8021q_tag qtag; 446 struct ether_header *eh; 447 448 eh = mtod(*mp, struct ether_header *); 449 if (ntohs(eh->ether_type) == ETHERTYPE_VLAN || 450 ntohs(eh->ether_type) == ETHERTYPE_QINQ) 451 return (true); 452 453 qtag.vid = 0; 454 qtag.pcp = pcp; 455 qtag.proto = ETHERTYPE_VLAN; 456 if (ether_8021q_frame(mp, ifp, ifp, &qtag)) 457 return (true); 458 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 459 return (false); 460 } 461 462 /* 463 * Ethernet link layer output routine to send a raw frame to the device. 464 * 465 * This assumes that the 14 byte Ethernet header is present and contiguous 466 * in the first mbuf (if BRIDGE'ing). 467 */ 468 int 469 ether_output_frame(struct ifnet *ifp, struct mbuf *m) 470 { 471 uint8_t pcp; 472 473 pcp = ifp->if_pcp; 474 if (pcp != IFNET_PCP_NONE && ifp->if_type != IFT_L2VLAN && 475 !ether_set_pcp(&m, ifp, pcp)) 476 return (0); 477 478 if (PFIL_HOOKED_OUT(V_link_pfil_head)) 479 switch (pfil_mbuf_out(V_link_pfil_head, &m, ifp, NULL)) { 480 case PFIL_DROPPED: 481 return (EACCES); 482 case PFIL_CONSUMED: 483 return (0); 484 } 485 486 #ifdef EXPERIMENTAL 487 #if defined(INET6) && defined(INET) 488 /* draft-ietf-6man-ipv6only-flag */ 489 /* Catch ETHERTYPE_IP, and ETHERTYPE_[REV]ARP if we are v6-only. */ 490 if ((ND_IFINFO(ifp)->flags & ND6_IFF_IPV6_ONLY_MASK) != 0) { 491 struct ether_header *eh; 492 493 eh = mtod(m, struct ether_header *); 494 switch (ntohs(eh->ether_type)) { 495 case ETHERTYPE_IP: 496 case ETHERTYPE_ARP: 497 case ETHERTYPE_REVARP: 498 m_freem(m); 499 return (EAFNOSUPPORT); 500 /* NOTREACHED */ 501 break; 502 }; 503 } 504 #endif 505 #endif 506 507 /* 508 * Queue message on interface, update output statistics if successful, 509 * and start output if interface not yet active. 510 * 511 * If KMSAN is enabled, use it to verify that the data does not contain 512 * any uninitialized bytes. 513 */ 514 kmsan_check_mbuf(m, "ether_output"); 515 return ((ifp->if_transmit)(ifp, m)); 516 } 517 518 /* 519 * Process a received Ethernet packet; the packet is in the 520 * mbuf chain m with the ethernet header at the front. 521 */ 522 static void 523 ether_input_internal(struct ifnet *ifp, struct mbuf *m) 524 { 525 struct ether_header *eh; 526 u_short etype; 527 528 if ((ifp->if_flags & IFF_UP) == 0) { 529 m_freem(m); 530 return; 531 } 532 #ifdef DIAGNOSTIC 533 if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0) { 534 if_printf(ifp, "discard frame at !IFF_DRV_RUNNING\n"); 535 m_freem(m); 536 return; 537 } 538 #endif 539 if (m->m_len < ETHER_HDR_LEN) { 540 /* XXX maybe should pullup? */ 541 if_printf(ifp, "discard frame w/o leading ethernet " 542 "header (len %u pkt len %u)\n", 543 m->m_len, m->m_pkthdr.len); 544 if_inc_counter(ifp, IFCOUNTER_IERRORS, 1); 545 m_freem(m); 546 return; 547 } 548 eh = mtod(m, struct ether_header *); 549 etype = ntohs(eh->ether_type); 550 random_harvest_queue_ether(m, sizeof(*m)); 551 552 #ifdef EXPERIMENTAL 553 #if defined(INET6) && defined(INET) 554 /* draft-ietf-6man-ipv6only-flag */ 555 /* Catch ETHERTYPE_IP, and ETHERTYPE_[REV]ARP if we are v6-only. */ 556 if ((ND_IFINFO(ifp)->flags & ND6_IFF_IPV6_ONLY_MASK) != 0) { 557 switch (etype) { 558 case ETHERTYPE_IP: 559 case ETHERTYPE_ARP: 560 case ETHERTYPE_REVARP: 561 m_freem(m); 562 return; 563 /* NOTREACHED */ 564 break; 565 }; 566 } 567 #endif 568 #endif 569 570 CURVNET_SET_QUIET(ifp->if_vnet); 571 572 if (ETHER_IS_MULTICAST(eh->ether_dhost)) { 573 if (ETHER_IS_BROADCAST(eh->ether_dhost)) 574 m->m_flags |= M_BCAST; 575 else 576 m->m_flags |= M_MCAST; 577 if_inc_counter(ifp, IFCOUNTER_IMCASTS, 1); 578 } 579 580 #ifdef MAC 581 /* 582 * Tag the mbuf with an appropriate MAC label before any other 583 * consumers can get to it. 584 */ 585 mac_ifnet_create_mbuf(ifp, m); 586 #endif 587 588 /* 589 * Give bpf a chance at the packet. 590 */ 591 ETHER_BPF_MTAP(ifp, m); 592 593 /* 594 * If the CRC is still on the packet, trim it off. We do this once 595 * and once only in case we are re-entered. Nothing else on the 596 * Ethernet receive path expects to see the FCS. 597 */ 598 if (m->m_flags & M_HASFCS) { 599 m_adj(m, -ETHER_CRC_LEN); 600 m->m_flags &= ~M_HASFCS; 601 } 602 603 if (!(ifp->if_capenable & IFCAP_HWSTATS)) 604 if_inc_counter(ifp, IFCOUNTER_IBYTES, m->m_pkthdr.len); 605 606 /* Allow monitor mode to claim this frame, after stats are updated. */ 607 if (ifp->if_flags & IFF_MONITOR) { 608 m_freem(m); 609 CURVNET_RESTORE(); 610 return; 611 } 612 613 /* Handle input from a lagg(4) port */ 614 if (ifp->if_type == IFT_IEEE8023ADLAG) { 615 KASSERT(lagg_input_ethernet_p != NULL, 616 ("%s: if_lagg not loaded!", __func__)); 617 m = (*lagg_input_ethernet_p)(ifp, m); 618 if (m != NULL) 619 ifp = m->m_pkthdr.rcvif; 620 else { 621 CURVNET_RESTORE(); 622 return; 623 } 624 } 625 626 /* 627 * If the hardware did not process an 802.1Q tag, do this now, 628 * to allow 802.1P priority frames to be passed to the main input 629 * path correctly. 630 */ 631 if ((m->m_flags & M_VLANTAG) == 0 && 632 ((etype == ETHERTYPE_VLAN) || (etype == ETHERTYPE_QINQ))) { 633 struct ether_vlan_header *evl; 634 635 if (m->m_len < sizeof(*evl) && 636 (m = m_pullup(m, sizeof(*evl))) == NULL) { 637 #ifdef DIAGNOSTIC 638 if_printf(ifp, "cannot pullup VLAN header\n"); 639 #endif 640 if_inc_counter(ifp, IFCOUNTER_IERRORS, 1); 641 CURVNET_RESTORE(); 642 return; 643 } 644 645 evl = mtod(m, struct ether_vlan_header *); 646 m->m_pkthdr.ether_vtag = ntohs(evl->evl_tag); 647 m->m_flags |= M_VLANTAG; 648 649 bcopy((char *)evl, (char *)evl + ETHER_VLAN_ENCAP_LEN, 650 ETHER_HDR_LEN - ETHER_TYPE_LEN); 651 m_adj(m, ETHER_VLAN_ENCAP_LEN); 652 eh = mtod(m, struct ether_header *); 653 } 654 655 M_SETFIB(m, ifp->if_fib); 656 657 /* Allow ng_ether(4) to claim this frame. */ 658 if (ifp->if_l2com != NULL) { 659 KASSERT(ng_ether_input_p != NULL, 660 ("%s: ng_ether_input_p is NULL", __func__)); 661 m->m_flags &= ~M_PROMISC; 662 (*ng_ether_input_p)(ifp, &m); 663 if (m == NULL) { 664 CURVNET_RESTORE(); 665 return; 666 } 667 eh = mtod(m, struct ether_header *); 668 } 669 670 /* 671 * Allow if_bridge(4) to claim this frame. 672 * 673 * The BRIDGE_INPUT() macro will update ifp if the bridge changed it 674 * and the frame should be delivered locally. 675 * 676 * If M_BRIDGE_INJECT is set, the packet was received directly by the 677 * bridge via netmap, so "ifp" is the bridge itself and the packet 678 * should be re-examined. 679 */ 680 if (ifp->if_bridge != NULL || (m->m_flags & M_BRIDGE_INJECT) != 0) { 681 m->m_flags &= ~M_PROMISC; 682 BRIDGE_INPUT(ifp, m); 683 if (m == NULL) { 684 CURVNET_RESTORE(); 685 return; 686 } 687 eh = mtod(m, struct ether_header *); 688 } 689 690 #if defined(INET) || defined(INET6) 691 /* 692 * Clear M_PROMISC on frame so that carp(4) will see it when the 693 * mbuf flows up to Layer 3. 694 * FreeBSD's implementation of carp(4) uses the inprotosw 695 * to dispatch IPPROTO_CARP. carp(4) also allocates its own 696 * Ethernet addresses of the form 00:00:5e:00:01:xx, which 697 * is outside the scope of the M_PROMISC test below. 698 * TODO: Maintain a hash table of ethernet addresses other than 699 * ether_dhost which may be active on this ifp. 700 */ 701 if (ifp->if_carp && (*carp_forus_p)(ifp, eh->ether_dhost)) { 702 m->m_flags &= ~M_PROMISC; 703 } else 704 #endif 705 { 706 /* 707 * If the frame received was not for our MAC address, set the 708 * M_PROMISC flag on the mbuf chain. The frame may need to 709 * be seen by the rest of the Ethernet input path in case of 710 * re-entry (e.g. bridge, vlan, netgraph) but should not be 711 * seen by upper protocol layers. 712 */ 713 if (!ETHER_IS_MULTICAST(eh->ether_dhost) && 714 bcmp(IF_LLADDR(ifp), eh->ether_dhost, ETHER_ADDR_LEN) != 0) 715 m->m_flags |= M_PROMISC; 716 } 717 718 ether_demux(ifp, m); 719 CURVNET_RESTORE(); 720 } 721 722 /* 723 * Ethernet input dispatch; by default, direct dispatch here regardless of 724 * global configuration. However, if RSS is enabled, hook up RSS affinity 725 * so that when deferred or hybrid dispatch is enabled, we can redistribute 726 * load based on RSS. 727 * 728 * XXXRW: Would be nice if the ifnet passed up a flag indicating whether or 729 * not it had already done work distribution via multi-queue. Then we could 730 * direct dispatch in the event load balancing was already complete and 731 * handle the case of interfaces with different capabilities better. 732 * 733 * XXXRW: Sort of want an M_DISTRIBUTED flag to avoid multiple distributions 734 * at multiple layers? 735 * 736 * XXXRW: For now, enable all this only if RSS is compiled in, although it 737 * works fine without RSS. Need to characterise the performance overhead 738 * of the detour through the netisr code in the event the result is always 739 * direct dispatch. 740 */ 741 static void 742 ether_nh_input(struct mbuf *m) 743 { 744 745 M_ASSERTPKTHDR(m); 746 KASSERT(m->m_pkthdr.rcvif != NULL, 747 ("%s: NULL interface pointer", __func__)); 748 ether_input_internal(m->m_pkthdr.rcvif, m); 749 } 750 751 static struct netisr_handler ether_nh = { 752 .nh_name = "ether", 753 .nh_handler = ether_nh_input, 754 .nh_proto = NETISR_ETHER, 755 #ifdef RSS 756 .nh_policy = NETISR_POLICY_CPU, 757 .nh_dispatch = NETISR_DISPATCH_DIRECT, 758 .nh_m2cpuid = rss_m2cpuid, 759 #else 760 .nh_policy = NETISR_POLICY_SOURCE, 761 .nh_dispatch = NETISR_DISPATCH_DIRECT, 762 #endif 763 }; 764 765 static void 766 ether_init(__unused void *arg) 767 { 768 769 netisr_register(ðer_nh); 770 } 771 SYSINIT(ether, SI_SUB_INIT_IF, SI_ORDER_ANY, ether_init, NULL); 772 773 static void 774 vnet_ether_init(__unused void *arg) 775 { 776 struct pfil_head_args args; 777 778 args.pa_version = PFIL_VERSION; 779 args.pa_flags = PFIL_IN | PFIL_OUT; 780 args.pa_type = PFIL_TYPE_ETHERNET; 781 args.pa_headname = PFIL_ETHER_NAME; 782 V_link_pfil_head = pfil_head_register(&args); 783 784 #ifdef VIMAGE 785 netisr_register_vnet(ðer_nh); 786 #endif 787 } 788 VNET_SYSINIT(vnet_ether_init, SI_SUB_PROTO_IF, SI_ORDER_ANY, 789 vnet_ether_init, NULL); 790 791 #ifdef VIMAGE 792 static void 793 vnet_ether_pfil_destroy(__unused void *arg) 794 { 795 796 pfil_head_unregister(V_link_pfil_head); 797 } 798 VNET_SYSUNINIT(vnet_ether_pfil_uninit, SI_SUB_PROTO_PFIL, SI_ORDER_ANY, 799 vnet_ether_pfil_destroy, NULL); 800 801 static void 802 vnet_ether_destroy(__unused void *arg) 803 { 804 805 netisr_unregister_vnet(ðer_nh); 806 } 807 VNET_SYSUNINIT(vnet_ether_uninit, SI_SUB_PROTO_IF, SI_ORDER_ANY, 808 vnet_ether_destroy, NULL); 809 #endif 810 811 static void 812 ether_input(struct ifnet *ifp, struct mbuf *m) 813 { 814 struct epoch_tracker et; 815 struct mbuf *mn; 816 bool needs_epoch; 817 818 needs_epoch = (ifp->if_flags & IFF_NEEDSEPOCH); 819 #ifdef INVARIANTS 820 /* 821 * This temporary code is here to prevent epoch unaware and unmarked 822 * drivers to panic the system. Once all drivers are taken care of, 823 * the whole INVARIANTS block should go away. 824 */ 825 if (!needs_epoch && !in_epoch(net_epoch_preempt)) { 826 static bool printedonce; 827 828 needs_epoch = true; 829 if (!printedonce) { 830 printedonce = true; 831 if_printf(ifp, "called %s w/o net epoch! " 832 "PLEASE file a bug report.", __func__); 833 #ifdef KDB 834 kdb_backtrace(); 835 #endif 836 } 837 } 838 #endif 839 840 /* 841 * The drivers are allowed to pass in a chain of packets linked with 842 * m_nextpkt. We split them up into separate packets here and pass 843 * them up. This allows the drivers to amortize the receive lock. 844 */ 845 CURVNET_SET_QUIET(ifp->if_vnet); 846 if (__predict_false(needs_epoch)) 847 NET_EPOCH_ENTER(et); 848 while (m) { 849 mn = m->m_nextpkt; 850 m->m_nextpkt = NULL; 851 852 /* 853 * We will rely on rcvif being set properly in the deferred 854 * context, so assert it is correct here. 855 */ 856 MPASS((m->m_pkthdr.csum_flags & CSUM_SND_TAG) == 0); 857 KASSERT(m->m_pkthdr.rcvif == ifp, ("%s: ifnet mismatch m %p " 858 "rcvif %p ifp %p", __func__, m, m->m_pkthdr.rcvif, ifp)); 859 netisr_dispatch(NETISR_ETHER, m); 860 m = mn; 861 } 862 if (__predict_false(needs_epoch)) 863 NET_EPOCH_EXIT(et); 864 CURVNET_RESTORE(); 865 } 866 867 /* 868 * Upper layer processing for a received Ethernet packet. 869 */ 870 void 871 ether_demux(struct ifnet *ifp, struct mbuf *m) 872 { 873 struct ether_header *eh; 874 int i, isr; 875 u_short ether_type; 876 877 NET_EPOCH_ASSERT(); 878 KASSERT(ifp != NULL, ("%s: NULL interface pointer", __func__)); 879 880 /* Do not grab PROMISC frames in case we are re-entered. */ 881 if (PFIL_HOOKED_IN(V_link_pfil_head) && !(m->m_flags & M_PROMISC)) { 882 i = pfil_mbuf_in(V_link_pfil_head, &m, ifp, NULL); 883 if (i != 0 || m == NULL) 884 return; 885 } 886 887 eh = mtod(m, struct ether_header *); 888 ether_type = ntohs(eh->ether_type); 889 890 /* 891 * If this frame has a VLAN tag other than 0, call vlan_input() 892 * if its module is loaded. Otherwise, drop. 893 */ 894 if ((m->m_flags & M_VLANTAG) && 895 EVL_VLANOFTAG(m->m_pkthdr.ether_vtag) != 0) { 896 if (ifp->if_vlantrunk == NULL) { 897 if_inc_counter(ifp, IFCOUNTER_NOPROTO, 1); 898 m_freem(m); 899 return; 900 } 901 KASSERT(vlan_input_p != NULL,("%s: VLAN not loaded!", 902 __func__)); 903 /* Clear before possibly re-entering ether_input(). */ 904 m->m_flags &= ~M_PROMISC; 905 (*vlan_input_p)(ifp, m); 906 return; 907 } 908 909 /* 910 * Pass promiscuously received frames to the upper layer if the user 911 * requested this by setting IFF_PPROMISC. Otherwise, drop them. 912 */ 913 if ((ifp->if_flags & IFF_PPROMISC) == 0 && (m->m_flags & M_PROMISC)) { 914 m_freem(m); 915 return; 916 } 917 918 /* 919 * Reset layer specific mbuf flags to avoid confusing upper layers. 920 */ 921 m->m_flags &= ~M_VLANTAG; 922 m_clrprotoflags(m); 923 924 /* 925 * Dispatch frame to upper layer. 926 */ 927 switch (ether_type) { 928 #ifdef INET 929 case ETHERTYPE_IP: 930 isr = NETISR_IP; 931 break; 932 933 case ETHERTYPE_ARP: 934 if (ifp->if_flags & IFF_NOARP) { 935 /* Discard packet if ARP is disabled on interface */ 936 m_freem(m); 937 return; 938 } 939 isr = NETISR_ARP; 940 break; 941 #endif 942 #ifdef INET6 943 case ETHERTYPE_IPV6: 944 isr = NETISR_IPV6; 945 break; 946 #endif 947 default: 948 goto discard; 949 } 950 951 /* Strip off Ethernet header. */ 952 m_adj(m, ETHER_HDR_LEN); 953 954 netisr_dispatch(isr, m); 955 return; 956 957 discard: 958 /* 959 * Packet is to be discarded. If netgraph is present, 960 * hand the packet to it for last chance processing; 961 * otherwise dispose of it. 962 */ 963 if (ifp->if_l2com != NULL) { 964 KASSERT(ng_ether_input_orphan_p != NULL, 965 ("ng_ether_input_orphan_p is NULL")); 966 (*ng_ether_input_orphan_p)(ifp, m); 967 return; 968 } 969 m_freem(m); 970 } 971 972 /* 973 * Convert Ethernet address to printable (loggable) representation. 974 * This routine is for compatibility; it's better to just use 975 * 976 * printf("%6D", <pointer to address>, ":"); 977 * 978 * since there's no static buffer involved. 979 */ 980 char * 981 ether_sprintf(const u_char *ap) 982 { 983 static char etherbuf[18]; 984 snprintf(etherbuf, sizeof (etherbuf), "%6D", ap, ":"); 985 return (etherbuf); 986 } 987 988 /* 989 * Perform common duties while attaching to interface list 990 */ 991 void 992 ether_ifattach(struct ifnet *ifp, const u_int8_t *lla) 993 { 994 int i; 995 struct ifaddr *ifa; 996 struct sockaddr_dl *sdl; 997 998 ifp->if_addrlen = ETHER_ADDR_LEN; 999 ifp->if_hdrlen = ETHER_HDR_LEN; 1000 ifp->if_mtu = ETHERMTU; 1001 if_attach(ifp); 1002 ifp->if_output = ether_output; 1003 ifp->if_input = ether_input; 1004 ifp->if_resolvemulti = ether_resolvemulti; 1005 ifp->if_requestencap = ether_requestencap; 1006 #ifdef VIMAGE 1007 ifp->if_reassign = ether_reassign; 1008 #endif 1009 if (ifp->if_baudrate == 0) 1010 ifp->if_baudrate = IF_Mbps(10); /* just a default */ 1011 ifp->if_broadcastaddr = etherbroadcastaddr; 1012 1013 ifa = ifp->if_addr; 1014 KASSERT(ifa != NULL, ("%s: no lladdr!\n", __func__)); 1015 sdl = (struct sockaddr_dl *)ifa->ifa_addr; 1016 sdl->sdl_type = IFT_ETHER; 1017 sdl->sdl_alen = ifp->if_addrlen; 1018 bcopy(lla, LLADDR(sdl), ifp->if_addrlen); 1019 1020 if (ifp->if_hw_addr != NULL) 1021 bcopy(lla, ifp->if_hw_addr, ifp->if_addrlen); 1022 1023 bpfattach(ifp, DLT_EN10MB, ETHER_HDR_LEN); 1024 if (ng_ether_attach_p != NULL) 1025 (*ng_ether_attach_p)(ifp); 1026 1027 /* Announce Ethernet MAC address if non-zero. */ 1028 for (i = 0; i < ifp->if_addrlen; i++) 1029 if (lla[i] != 0) 1030 break; 1031 if (i != ifp->if_addrlen) 1032 if_printf(ifp, "Ethernet address: %6D\n", lla, ":"); 1033 1034 uuid_ether_add(LLADDR(sdl)); 1035 1036 /* Add necessary bits are setup; announce it now. */ 1037 EVENTHANDLER_INVOKE(ether_ifattach_event, ifp); 1038 if (IS_DEFAULT_VNET(curvnet)) 1039 devctl_notify("ETHERNET", ifp->if_xname, "IFATTACH", NULL); 1040 } 1041 1042 /* 1043 * Perform common duties while detaching an Ethernet interface 1044 */ 1045 void 1046 ether_ifdetach(struct ifnet *ifp) 1047 { 1048 struct sockaddr_dl *sdl; 1049 1050 sdl = (struct sockaddr_dl *)(ifp->if_addr->ifa_addr); 1051 uuid_ether_del(LLADDR(sdl)); 1052 1053 if (ifp->if_l2com != NULL) { 1054 KASSERT(ng_ether_detach_p != NULL, 1055 ("ng_ether_detach_p is NULL")); 1056 (*ng_ether_detach_p)(ifp); 1057 } 1058 1059 bpfdetach(ifp); 1060 if_detach(ifp); 1061 } 1062 1063 #ifdef VIMAGE 1064 void 1065 ether_reassign(struct ifnet *ifp, struct vnet *new_vnet, char *unused __unused) 1066 { 1067 1068 if (ifp->if_l2com != NULL) { 1069 KASSERT(ng_ether_detach_p != NULL, 1070 ("ng_ether_detach_p is NULL")); 1071 (*ng_ether_detach_p)(ifp); 1072 } 1073 1074 if (ng_ether_attach_p != NULL) { 1075 CURVNET_SET_QUIET(new_vnet); 1076 (*ng_ether_attach_p)(ifp); 1077 CURVNET_RESTORE(); 1078 } 1079 } 1080 #endif 1081 1082 SYSCTL_DECL(_net_link); 1083 SYSCTL_NODE(_net_link, IFT_ETHER, ether, CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 1084 "Ethernet"); 1085 1086 #if 0 1087 /* 1088 * This is for reference. We have a table-driven version 1089 * of the little-endian crc32 generator, which is faster 1090 * than the double-loop. 1091 */ 1092 uint32_t 1093 ether_crc32_le(const uint8_t *buf, size_t len) 1094 { 1095 size_t i; 1096 uint32_t crc; 1097 int bit; 1098 uint8_t data; 1099 1100 crc = 0xffffffff; /* initial value */ 1101 1102 for (i = 0; i < len; i++) { 1103 for (data = *buf++, bit = 0; bit < 8; bit++, data >>= 1) { 1104 carry = (crc ^ data) & 1; 1105 crc >>= 1; 1106 if (carry) 1107 crc = (crc ^ ETHER_CRC_POLY_LE); 1108 } 1109 } 1110 1111 return (crc); 1112 } 1113 #else 1114 uint32_t 1115 ether_crc32_le(const uint8_t *buf, size_t len) 1116 { 1117 static const uint32_t crctab[] = { 1118 0x00000000, 0x1db71064, 0x3b6e20c8, 0x26d930ac, 1119 0x76dc4190, 0x6b6b51f4, 0x4db26158, 0x5005713c, 1120 0xedb88320, 0xf00f9344, 0xd6d6a3e8, 0xcb61b38c, 1121 0x9b64c2b0, 0x86d3d2d4, 0xa00ae278, 0xbdbdf21c 1122 }; 1123 size_t i; 1124 uint32_t crc; 1125 1126 crc = 0xffffffff; /* initial value */ 1127 1128 for (i = 0; i < len; i++) { 1129 crc ^= buf[i]; 1130 crc = (crc >> 4) ^ crctab[crc & 0xf]; 1131 crc = (crc >> 4) ^ crctab[crc & 0xf]; 1132 } 1133 1134 return (crc); 1135 } 1136 #endif 1137 1138 uint32_t 1139 ether_crc32_be(const uint8_t *buf, size_t len) 1140 { 1141 size_t i; 1142 uint32_t crc, carry; 1143 int bit; 1144 uint8_t data; 1145 1146 crc = 0xffffffff; /* initial value */ 1147 1148 for (i = 0; i < len; i++) { 1149 for (data = *buf++, bit = 0; bit < 8; bit++, data >>= 1) { 1150 carry = ((crc & 0x80000000) ? 1 : 0) ^ (data & 0x01); 1151 crc <<= 1; 1152 if (carry) 1153 crc = (crc ^ ETHER_CRC_POLY_BE) | carry; 1154 } 1155 } 1156 1157 return (crc); 1158 } 1159 1160 int 1161 ether_ioctl(struct ifnet *ifp, u_long command, caddr_t data) 1162 { 1163 struct ifaddr *ifa = (struct ifaddr *) data; 1164 struct ifreq *ifr = (struct ifreq *) data; 1165 int error = 0; 1166 1167 switch (command) { 1168 case SIOCSIFADDR: 1169 ifp->if_flags |= IFF_UP; 1170 1171 switch (ifa->ifa_addr->sa_family) { 1172 #ifdef INET 1173 case AF_INET: 1174 ifp->if_init(ifp->if_softc); /* before arpwhohas */ 1175 arp_ifinit(ifp, ifa); 1176 break; 1177 #endif 1178 default: 1179 ifp->if_init(ifp->if_softc); 1180 break; 1181 } 1182 break; 1183 1184 case SIOCGIFADDR: 1185 bcopy(IF_LLADDR(ifp), &ifr->ifr_addr.sa_data[0], 1186 ETHER_ADDR_LEN); 1187 break; 1188 1189 case SIOCSIFMTU: 1190 /* 1191 * Set the interface MTU. 1192 */ 1193 if (ifr->ifr_mtu > ETHERMTU) { 1194 error = EINVAL; 1195 } else { 1196 ifp->if_mtu = ifr->ifr_mtu; 1197 } 1198 break; 1199 1200 case SIOCSLANPCP: 1201 error = priv_check(curthread, PRIV_NET_SETLANPCP); 1202 if (error != 0) 1203 break; 1204 if (ifr->ifr_lan_pcp > 7 && 1205 ifr->ifr_lan_pcp != IFNET_PCP_NONE) { 1206 error = EINVAL; 1207 } else { 1208 ifp->if_pcp = ifr->ifr_lan_pcp; 1209 /* broadcast event about PCP change */ 1210 EVENTHANDLER_INVOKE(ifnet_event, ifp, IFNET_EVENT_PCP); 1211 } 1212 break; 1213 1214 case SIOCGLANPCP: 1215 ifr->ifr_lan_pcp = ifp->if_pcp; 1216 break; 1217 1218 default: 1219 error = EINVAL; /* XXX netbsd has ENOTTY??? */ 1220 break; 1221 } 1222 return (error); 1223 } 1224 1225 static int 1226 ether_resolvemulti(struct ifnet *ifp, struct sockaddr **llsa, 1227 struct sockaddr *sa) 1228 { 1229 struct sockaddr_dl *sdl; 1230 #ifdef INET 1231 struct sockaddr_in *sin; 1232 #endif 1233 #ifdef INET6 1234 struct sockaddr_in6 *sin6; 1235 #endif 1236 u_char *e_addr; 1237 1238 switch(sa->sa_family) { 1239 case AF_LINK: 1240 /* 1241 * No mapping needed. Just check that it's a valid MC address. 1242 */ 1243 sdl = (struct sockaddr_dl *)sa; 1244 e_addr = LLADDR(sdl); 1245 if (!ETHER_IS_MULTICAST(e_addr)) 1246 return EADDRNOTAVAIL; 1247 *llsa = NULL; 1248 return 0; 1249 1250 #ifdef INET 1251 case AF_INET: 1252 sin = (struct sockaddr_in *)sa; 1253 if (!IN_MULTICAST(ntohl(sin->sin_addr.s_addr))) 1254 return EADDRNOTAVAIL; 1255 sdl = link_init_sdl(ifp, *llsa, IFT_ETHER); 1256 sdl->sdl_alen = ETHER_ADDR_LEN; 1257 e_addr = LLADDR(sdl); 1258 ETHER_MAP_IP_MULTICAST(&sin->sin_addr, e_addr); 1259 *llsa = (struct sockaddr *)sdl; 1260 return 0; 1261 #endif 1262 #ifdef INET6 1263 case AF_INET6: 1264 sin6 = (struct sockaddr_in6 *)sa; 1265 if (IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr)) { 1266 /* 1267 * An IP6 address of 0 means listen to all 1268 * of the Ethernet multicast address used for IP6. 1269 * (This is used for multicast routers.) 1270 */ 1271 ifp->if_flags |= IFF_ALLMULTI; 1272 *llsa = NULL; 1273 return 0; 1274 } 1275 if (!IN6_IS_ADDR_MULTICAST(&sin6->sin6_addr)) 1276 return EADDRNOTAVAIL; 1277 sdl = link_init_sdl(ifp, *llsa, IFT_ETHER); 1278 sdl->sdl_alen = ETHER_ADDR_LEN; 1279 e_addr = LLADDR(sdl); 1280 ETHER_MAP_IPV6_MULTICAST(&sin6->sin6_addr, e_addr); 1281 *llsa = (struct sockaddr *)sdl; 1282 return 0; 1283 #endif 1284 1285 default: 1286 /* 1287 * Well, the text isn't quite right, but it's the name 1288 * that counts... 1289 */ 1290 return EAFNOSUPPORT; 1291 } 1292 } 1293 1294 static moduledata_t ether_mod = { 1295 .name = "ether", 1296 }; 1297 1298 void 1299 ether_vlan_mtap(struct bpf_if *bp, struct mbuf *m, void *data, u_int dlen) 1300 { 1301 struct ether_vlan_header vlan; 1302 struct mbuf mv, mb; 1303 1304 KASSERT((m->m_flags & M_VLANTAG) != 0, 1305 ("%s: vlan information not present", __func__)); 1306 KASSERT(m->m_len >= sizeof(struct ether_header), 1307 ("%s: mbuf not large enough for header", __func__)); 1308 bcopy(mtod(m, char *), &vlan, sizeof(struct ether_header)); 1309 vlan.evl_proto = vlan.evl_encap_proto; 1310 vlan.evl_encap_proto = htons(ETHERTYPE_VLAN); 1311 vlan.evl_tag = htons(m->m_pkthdr.ether_vtag); 1312 m->m_len -= sizeof(struct ether_header); 1313 m->m_data += sizeof(struct ether_header); 1314 /* 1315 * If a data link has been supplied by the caller, then we will need to 1316 * re-create a stack allocated mbuf chain with the following structure: 1317 * 1318 * (1) mbuf #1 will contain the supplied data link 1319 * (2) mbuf #2 will contain the vlan header 1320 * (3) mbuf #3 will contain the original mbuf's packet data 1321 * 1322 * Otherwise, submit the packet and vlan header via bpf_mtap2(). 1323 */ 1324 if (data != NULL) { 1325 mv.m_next = m; 1326 mv.m_data = (caddr_t)&vlan; 1327 mv.m_len = sizeof(vlan); 1328 mb.m_next = &mv; 1329 mb.m_data = data; 1330 mb.m_len = dlen; 1331 bpf_mtap(bp, &mb); 1332 } else 1333 bpf_mtap2(bp, &vlan, sizeof(vlan), m); 1334 m->m_len += sizeof(struct ether_header); 1335 m->m_data -= sizeof(struct ether_header); 1336 } 1337 1338 struct mbuf * 1339 ether_vlanencap_proto(struct mbuf *m, uint16_t tag, uint16_t proto) 1340 { 1341 struct ether_vlan_header *evl; 1342 1343 M_PREPEND(m, ETHER_VLAN_ENCAP_LEN, M_NOWAIT); 1344 if (m == NULL) 1345 return (NULL); 1346 /* M_PREPEND takes care of m_len, m_pkthdr.len for us */ 1347 1348 if (m->m_len < sizeof(*evl)) { 1349 m = m_pullup(m, sizeof(*evl)); 1350 if (m == NULL) 1351 return (NULL); 1352 } 1353 1354 /* 1355 * Transform the Ethernet header into an Ethernet header 1356 * with 802.1Q encapsulation. 1357 */ 1358 evl = mtod(m, struct ether_vlan_header *); 1359 bcopy((char *)evl + ETHER_VLAN_ENCAP_LEN, 1360 (char *)evl, ETHER_HDR_LEN - ETHER_TYPE_LEN); 1361 evl->evl_encap_proto = htons(proto); 1362 evl->evl_tag = htons(tag); 1363 return (m); 1364 } 1365 1366 void 1367 ether_bpf_mtap_if(struct ifnet *ifp, struct mbuf *m) 1368 { 1369 if (bpf_peers_present(ifp->if_bpf)) { 1370 M_ASSERTVALID(m); 1371 if ((m->m_flags & M_VLANTAG) != 0) 1372 ether_vlan_mtap(ifp->if_bpf, m, NULL, 0); 1373 else 1374 bpf_mtap(ifp->if_bpf, m); 1375 } 1376 } 1377 1378 static SYSCTL_NODE(_net_link, IFT_L2VLAN, vlan, CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 1379 "IEEE 802.1Q VLAN"); 1380 static SYSCTL_NODE(_net_link_vlan, PF_LINK, link, 1381 CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 1382 "for consistency"); 1383 1384 VNET_DEFINE_STATIC(int, soft_pad); 1385 #define V_soft_pad VNET(soft_pad) 1386 SYSCTL_INT(_net_link_vlan, OID_AUTO, soft_pad, CTLFLAG_RW | CTLFLAG_VNET, 1387 &VNET_NAME(soft_pad), 0, 1388 "pad short frames before tagging"); 1389 1390 /* 1391 * For now, make preserving PCP via an mbuf tag optional, as it increases 1392 * per-packet memory allocations and frees. In the future, it would be 1393 * preferable to reuse ether_vtag for this, or similar. 1394 */ 1395 VNET_DEFINE(int, vlan_mtag_pcp) = 0; 1396 #define V_vlan_mtag_pcp VNET(vlan_mtag_pcp) 1397 SYSCTL_INT(_net_link_vlan, OID_AUTO, mtag_pcp, CTLFLAG_RW | CTLFLAG_VNET, 1398 &VNET_NAME(vlan_mtag_pcp), 0, 1399 "Retain VLAN PCP information as packets are passed up the stack"); 1400 1401 bool 1402 ether_8021q_frame(struct mbuf **mp, struct ifnet *ife, struct ifnet *p, 1403 const struct ether_8021q_tag *qtag) 1404 { 1405 struct m_tag *mtag; 1406 int n; 1407 uint16_t tag; 1408 uint8_t pcp = qtag->pcp; 1409 static const char pad[8]; /* just zeros */ 1410 1411 /* 1412 * Pad the frame to the minimum size allowed if told to. 1413 * This option is in accord with IEEE Std 802.1Q, 2003 Ed., 1414 * paragraph C.4.4.3.b. It can help to work around buggy 1415 * bridges that violate paragraph C.4.4.3.a from the same 1416 * document, i.e., fail to pad short frames after untagging. 1417 * E.g., a tagged frame 66 bytes long (incl. FCS) is OK, but 1418 * untagging it will produce a 62-byte frame, which is a runt 1419 * and requires padding. There are VLAN-enabled network 1420 * devices that just discard such runts instead or mishandle 1421 * them somehow. 1422 */ 1423 if (V_soft_pad && p->if_type == IFT_ETHER) { 1424 for (n = ETHERMIN + ETHER_HDR_LEN - (*mp)->m_pkthdr.len; 1425 n > 0; n -= sizeof(pad)) { 1426 if (!m_append(*mp, min(n, sizeof(pad)), pad)) 1427 break; 1428 } 1429 if (n > 0) { 1430 m_freem(*mp); 1431 *mp = NULL; 1432 if_printf(ife, "cannot pad short frame"); 1433 return (false); 1434 } 1435 } 1436 1437 /* 1438 * If PCP is set in mbuf, use it 1439 */ 1440 if ((*mp)->m_flags & M_VLANTAG) { 1441 pcp = EVL_PRIOFTAG((*mp)->m_pkthdr.ether_vtag); 1442 } 1443 1444 /* 1445 * If underlying interface can do VLAN tag insertion itself, 1446 * just pass the packet along. However, we need some way to 1447 * tell the interface where the packet came from so that it 1448 * knows how to find the VLAN tag to use, so we attach a 1449 * packet tag that holds it. 1450 */ 1451 if (V_vlan_mtag_pcp && (mtag = m_tag_locate(*mp, MTAG_8021Q, 1452 MTAG_8021Q_PCP_OUT, NULL)) != NULL) 1453 tag = EVL_MAKETAG(qtag->vid, *(uint8_t *)(mtag + 1), 0); 1454 else 1455 tag = EVL_MAKETAG(qtag->vid, pcp, 0); 1456 if ((p->if_capenable & IFCAP_VLAN_HWTAGGING) && 1457 (qtag->proto == ETHERTYPE_VLAN)) { 1458 (*mp)->m_pkthdr.ether_vtag = tag; 1459 (*mp)->m_flags |= M_VLANTAG; 1460 } else { 1461 *mp = ether_vlanencap_proto(*mp, tag, qtag->proto); 1462 if (*mp == NULL) { 1463 if_printf(ife, "unable to prepend 802.1Q header"); 1464 return (false); 1465 } 1466 } 1467 return (true); 1468 } 1469 1470 /* 1471 * Allocate an address from the FreeBSD Foundation OUI. This uses a 1472 * cryptographic hash function on the containing jail's name, UUID and the 1473 * interface name to attempt to provide a unique but stable address. 1474 * Pseudo-interfaces which require a MAC address should use this function to 1475 * allocate non-locally-administered addresses. 1476 */ 1477 void 1478 ether_gen_addr(struct ifnet *ifp, struct ether_addr *hwaddr) 1479 { 1480 SHA1_CTX ctx; 1481 char *buf; 1482 char uuid[HOSTUUIDLEN + 1]; 1483 uint64_t addr; 1484 int i, sz; 1485 char digest[SHA1_RESULTLEN]; 1486 char jailname[MAXHOSTNAMELEN]; 1487 1488 getcredhostuuid(curthread->td_ucred, uuid, sizeof(uuid)); 1489 if (strncmp(uuid, DEFAULT_HOSTUUID, sizeof(uuid)) == 0) { 1490 /* Fall back to a random mac address. */ 1491 goto rando; 1492 } 1493 1494 /* If each (vnet) jail would also have a unique hostuuid this would not 1495 * be necessary. */ 1496 getjailname(curthread->td_ucred, jailname, sizeof(jailname)); 1497 sz = asprintf(&buf, M_TEMP, "%s-%s-%s", uuid, if_name(ifp), 1498 jailname); 1499 if (sz < 0) { 1500 /* Fall back to a random mac address. */ 1501 goto rando; 1502 } 1503 1504 SHA1Init(&ctx); 1505 SHA1Update(&ctx, buf, sz); 1506 SHA1Final(digest, &ctx); 1507 free(buf, M_TEMP); 1508 1509 addr = ((digest[0] << 16) | (digest[1] << 8) | digest[2]) & 1510 OUI_FREEBSD_GENERATED_MASK; 1511 addr = OUI_FREEBSD(addr); 1512 for (i = 0; i < ETHER_ADDR_LEN; ++i) { 1513 hwaddr->octet[i] = addr >> ((ETHER_ADDR_LEN - i - 1) * 8) & 1514 0xFF; 1515 } 1516 1517 return; 1518 rando: 1519 arc4rand(hwaddr, sizeof(*hwaddr), 0); 1520 /* Unicast */ 1521 hwaddr->octet[0] &= 0xFE; 1522 /* Locally administered. */ 1523 hwaddr->octet[0] |= 0x02; 1524 } 1525 1526 DECLARE_MODULE(ether, ether_mod, SI_SUB_INIT_IF, SI_ORDER_ANY); 1527 MODULE_VERSION(ether, 1); 1528