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 32 #include "opt_inet.h" 33 #include "opt_inet6.h" 34 #include "opt_netgraph.h" 35 #include "opt_mbuf_profiling.h" 36 #include "opt_rss.h" 37 38 #include <sys/param.h> 39 #include <sys/systm.h> 40 #include <sys/devctl.h> 41 #include <sys/eventhandler.h> 42 #include <sys/jail.h> 43 #include <sys/kernel.h> 44 #include <sys/lock.h> 45 #include <sys/malloc.h> 46 #include <sys/mbuf.h> 47 #include <sys/module.h> 48 #include <sys/msan.h> 49 #include <sys/proc.h> 50 #include <sys/priv.h> 51 #include <sys/random.h> 52 #include <sys/socket.h> 53 #include <sys/sockio.h> 54 #include <sys/sysctl.h> 55 #include <sys/uuid.h> 56 #ifdef KDB 57 #include <sys/kdb.h> 58 #endif 59 60 #include <net/ieee_oui.h> 61 #include <net/if.h> 62 #include <net/if_var.h> 63 #include <net/if_private.h> 64 #include <net/if_arp.h> 65 #include <net/netisr.h> 66 #include <net/route.h> 67 #include <net/if_llc.h> 68 #include <net/if_dl.h> 69 #include <net/if_types.h> 70 #include <net/bpf.h> 71 #include <net/ethernet.h> 72 #include <net/if_bridgevar.h> 73 #include <net/if_vlan_var.h> 74 #include <net/if_llatbl.h> 75 #include <net/pfil.h> 76 #include <net/rss_config.h> 77 #include <net/vnet.h> 78 79 #include <netpfil/pf/pf_mtag.h> 80 81 #if defined(INET) || defined(INET6) 82 #include <netinet/in.h> 83 #include <netinet/in_var.h> 84 #include <netinet/if_ether.h> 85 #include <netinet/ip_carp.h> 86 #include <netinet/ip_var.h> 87 #endif 88 #ifdef INET6 89 #include <netinet6/nd6.h> 90 #endif 91 #include <security/mac/mac_framework.h> 92 93 #include <crypto/sha1.h> 94 95 #ifdef CTASSERT 96 CTASSERT(sizeof (struct ether_header) == ETHER_ADDR_LEN * 2 + 2); 97 CTASSERT(sizeof (struct ether_addr) == ETHER_ADDR_LEN); 98 #endif 99 100 VNET_DEFINE(pfil_head_t, link_pfil_head); /* Packet filter hooks */ 101 102 /* netgraph node hooks for ng_ether(4) */ 103 void (*ng_ether_input_p)(struct ifnet *ifp, struct mbuf **mp); 104 void (*ng_ether_input_orphan_p)(struct ifnet *ifp, struct mbuf *m); 105 int (*ng_ether_output_p)(struct ifnet *ifp, struct mbuf **mp); 106 void (*ng_ether_attach_p)(struct ifnet *ifp); 107 void (*ng_ether_detach_p)(struct ifnet *ifp); 108 109 void (*vlan_input_p)(struct ifnet *, struct mbuf *); 110 111 /* if_bridge(4) support */ 112 void (*bridge_dn_p)(struct mbuf *, struct ifnet *); 113 bool (*bridge_same_p)(const void *, const void *); 114 void *(*bridge_get_softc_p)(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 static inline bool ether_do_pcp(struct ifnet *, struct mbuf *); 127 128 #define senderr(e) do { error = (e); goto bad;} while (0) 129 130 static void 131 update_mbuf_csumflags(struct mbuf *src, struct mbuf *dst) 132 { 133 int csum_flags = 0; 134 135 if (src->m_pkthdr.csum_flags & CSUM_IP) 136 csum_flags |= (CSUM_IP_CHECKED|CSUM_IP_VALID); 137 if (src->m_pkthdr.csum_flags & CSUM_DELAY_DATA) 138 csum_flags |= (CSUM_DATA_VALID|CSUM_PSEUDO_HDR); 139 if (src->m_pkthdr.csum_flags & CSUM_SCTP) 140 csum_flags |= CSUM_SCTP_VALID; 141 dst->m_pkthdr.csum_flags |= csum_flags; 142 if (csum_flags & CSUM_DATA_VALID) 143 dst->m_pkthdr.csum_data = 0xffff; 144 } 145 146 /* 147 * Handle link-layer encapsulation requests. 148 */ 149 static int 150 ether_requestencap(struct ifnet *ifp, struct if_encap_req *req) 151 { 152 struct ether_header *eh; 153 struct arphdr *ah; 154 uint16_t etype; 155 const u_char *lladdr; 156 157 if (req->rtype != IFENCAP_LL) 158 return (EOPNOTSUPP); 159 160 if (req->bufsize < ETHER_HDR_LEN) 161 return (ENOMEM); 162 163 eh = (struct ether_header *)req->buf; 164 lladdr = req->lladdr; 165 req->lladdr_off = 0; 166 167 switch (req->family) { 168 case AF_INET: 169 etype = htons(ETHERTYPE_IP); 170 break; 171 case AF_INET6: 172 etype = htons(ETHERTYPE_IPV6); 173 break; 174 case AF_ARP: 175 ah = (struct arphdr *)req->hdata; 176 ah->ar_hrd = htons(ARPHRD_ETHER); 177 178 switch(ntohs(ah->ar_op)) { 179 case ARPOP_REVREQUEST: 180 case ARPOP_REVREPLY: 181 etype = htons(ETHERTYPE_REVARP); 182 break; 183 case ARPOP_REQUEST: 184 case ARPOP_REPLY: 185 default: 186 etype = htons(ETHERTYPE_ARP); 187 break; 188 } 189 190 if (req->flags & IFENCAP_FLAG_BROADCAST) 191 lladdr = ifp->if_broadcastaddr; 192 break; 193 default: 194 return (EAFNOSUPPORT); 195 } 196 197 memcpy(&eh->ether_type, &etype, sizeof(eh->ether_type)); 198 memcpy(eh->ether_dhost, lladdr, ETHER_ADDR_LEN); 199 memcpy(eh->ether_shost, IF_LLADDR(ifp), ETHER_ADDR_LEN); 200 req->bufsize = sizeof(struct ether_header); 201 202 return (0); 203 } 204 205 static int 206 ether_resolve_addr(struct ifnet *ifp, struct mbuf *m, 207 const struct sockaddr *dst, struct route *ro, u_char *phdr, 208 uint32_t *pflags, struct llentry **plle) 209 { 210 uint32_t lleflags = 0; 211 int error = 0; 212 #if defined(INET) || defined(INET6) 213 struct ether_header *eh = (struct ether_header *)phdr; 214 uint16_t etype; 215 #endif 216 217 if (plle) 218 *plle = NULL; 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 int af = RO_GET_FAMILY(ro, dst); 245 error = nd6_resolve(ifp, LLE_SF(af, 0), m, dst, phdr, 246 &lleflags, plle); 247 } else { 248 const struct in6_addr *a6; 249 a6 = &(((const struct sockaddr_in6 *)dst)->sin6_addr); 250 ETHER_MAP_IPV6_MULTICAST(a6, eh->ether_dhost); 251 etype = htons(ETHERTYPE_IPV6); 252 memcpy(&eh->ether_type, &etype, sizeof(etype)); 253 memcpy(eh->ether_shost, IF_LLADDR(ifp), ETHER_ADDR_LEN); 254 } 255 break; 256 #endif 257 default: 258 if_printf(ifp, "can't handle af%d\n", dst->sa_family); 259 if (m != NULL) 260 m_freem(m); 261 return (EAFNOSUPPORT); 262 } 263 264 if (error == EHOSTDOWN) { 265 if (ro != NULL && (ro->ro_flags & RT_HAS_GW) != 0) 266 error = EHOSTUNREACH; 267 } 268 269 if (error != 0) 270 return (error); 271 272 *pflags = RT_MAY_LOOP; 273 if (lleflags & LLE_IFADDR) 274 *pflags |= RT_L2_ME; 275 276 return (0); 277 } 278 279 /* 280 * Ethernet output routine. 281 * Encapsulate a packet of type family for the local net. 282 * Use trailer local net encapsulation if enough data in first 283 * packet leaves a multiple of 512 bytes of data in remainder. 284 */ 285 int 286 ether_output(struct ifnet *ifp, struct mbuf *m, 287 const struct sockaddr *dst, struct route *ro) 288 { 289 int error = 0; 290 char linkhdr[ETHER_HDR_LEN], *phdr; 291 struct ether_header *eh; 292 struct pf_mtag *t; 293 bool loop_copy; 294 int hlen; /* link layer header length */ 295 uint32_t pflags; 296 struct llentry *lle = NULL; 297 int addref = 0; 298 299 phdr = NULL; 300 pflags = 0; 301 if (ro != NULL) { 302 /* XXX BPF uses ro_prepend */ 303 if (ro->ro_prepend != NULL) { 304 phdr = ro->ro_prepend; 305 hlen = ro->ro_plen; 306 } else if (!(m->m_flags & (M_BCAST | M_MCAST))) { 307 if ((ro->ro_flags & RT_LLE_CACHE) != 0) { 308 lle = ro->ro_lle; 309 if (lle != NULL && 310 (lle->la_flags & LLE_VALID) == 0) { 311 LLE_FREE(lle); 312 lle = NULL; /* redundant */ 313 ro->ro_lle = NULL; 314 } 315 if (lle == NULL) { 316 /* if we lookup, keep cache */ 317 addref = 1; 318 } else 319 /* 320 * Notify LLE code that 321 * the entry was used 322 * by datapath. 323 */ 324 llentry_provide_feedback(lle); 325 } 326 if (lle != NULL) { 327 phdr = lle->r_linkdata; 328 hlen = lle->r_hdrlen; 329 pflags = lle->r_flags; 330 } 331 } 332 } 333 334 #ifdef MAC 335 error = mac_ifnet_check_transmit(ifp, m); 336 if (error) 337 senderr(error); 338 #endif 339 340 M_PROFILE(m); 341 if (ifp->if_flags & IFF_MONITOR) 342 senderr(ENETDOWN); 343 if (!((ifp->if_flags & IFF_UP) && 344 (ifp->if_drv_flags & IFF_DRV_RUNNING))) 345 senderr(ENETDOWN); 346 347 if (phdr == NULL) { 348 /* No prepend data supplied. Try to calculate ourselves. */ 349 phdr = linkhdr; 350 hlen = ETHER_HDR_LEN; 351 error = ether_resolve_addr(ifp, m, dst, ro, phdr, &pflags, 352 addref ? &lle : NULL); 353 if (addref && lle != NULL) 354 ro->ro_lle = lle; 355 if (error != 0) 356 return (error == EWOULDBLOCK ? 0 : error); 357 } 358 359 if ((pflags & RT_L2_ME) != 0) { 360 update_mbuf_csumflags(m, m); 361 return (if_simloop(ifp, m, RO_GET_FAMILY(ro, dst), 0)); 362 } 363 loop_copy = (pflags & RT_MAY_LOOP) != 0; 364 365 /* 366 * Add local net header. If no space in first mbuf, 367 * allocate another. 368 * 369 * Note that we do prepend regardless of RT_HAS_HEADER flag. 370 * This is done because BPF code shifts m_data pointer 371 * to the end of ethernet header prior to calling if_output(). 372 */ 373 M_PREPEND(m, hlen, M_NOWAIT); 374 if (m == NULL) 375 senderr(ENOBUFS); 376 if ((pflags & RT_HAS_HEADER) == 0) { 377 eh = mtod(m, struct ether_header *); 378 memcpy(eh, phdr, hlen); 379 } 380 381 /* 382 * If a simplex interface, and the packet is being sent to our 383 * Ethernet address or a broadcast address, loopback a copy. 384 * XXX To make a simplex device behave exactly like a duplex 385 * device, we should copy in the case of sending to our own 386 * ethernet address (thus letting the original actually appear 387 * on the wire). However, we don't do that here for security 388 * reasons and compatibility with the original behavior. 389 */ 390 if ((m->m_flags & M_BCAST) && loop_copy && (ifp->if_flags & IFF_SIMPLEX) && 391 ((t = pf_find_mtag(m)) == NULL || !t->routed)) { 392 struct mbuf *n; 393 394 /* 395 * Because if_simloop() modifies the packet, we need a 396 * writable copy through m_dup() instead of a readonly 397 * one as m_copy[m] would give us. The alternative would 398 * be to modify if_simloop() to handle the readonly mbuf, 399 * but performancewise it is mostly equivalent (trading 400 * extra data copying vs. extra locking). 401 * 402 * XXX This is a local workaround. A number of less 403 * often used kernel parts suffer from the same bug. 404 * See PR kern/105943 for a proposed general solution. 405 */ 406 if ((n = m_dup(m, M_NOWAIT)) != NULL) { 407 update_mbuf_csumflags(m, n); 408 (void)if_simloop(ifp, n, RO_GET_FAMILY(ro, dst), hlen); 409 } else 410 if_inc_counter(ifp, IFCOUNTER_IQDROPS, 1); 411 } 412 413 /* 414 * Bridges require special output handling. 415 */ 416 if (ifp->if_bridge) { 417 BRIDGE_OUTPUT(ifp, m, error); 418 return (error); 419 } 420 421 #if defined(INET) || defined(INET6) 422 if (ifp->if_carp && 423 (error = (*carp_output_p)(ifp, m, dst))) 424 goto bad; 425 #endif 426 427 /* Handle ng_ether(4) processing, if any */ 428 if (ifp->if_l2com != NULL) { 429 KASSERT(ng_ether_output_p != NULL, 430 ("ng_ether_output_p is NULL")); 431 if ((error = (*ng_ether_output_p)(ifp, &m)) != 0) { 432 bad: if (m != NULL) 433 m_freem(m); 434 return (error); 435 } 436 if (m == NULL) 437 return (0); 438 } 439 440 /* Continue with link-layer output */ 441 return ether_output_frame(ifp, m); 442 } 443 444 static bool 445 ether_set_pcp(struct mbuf **mp, struct ifnet *ifp, uint8_t pcp) 446 { 447 struct ether_8021q_tag qtag; 448 struct ether_header *eh; 449 450 eh = mtod(*mp, struct ether_header *); 451 if (eh->ether_type == htons(ETHERTYPE_VLAN) || 452 eh->ether_type == htons(ETHERTYPE_QINQ)) { 453 (*mp)->m_flags &= ~M_VLANTAG; 454 return (true); 455 } 456 457 qtag.vid = 0; 458 qtag.pcp = pcp; 459 qtag.proto = ETHERTYPE_VLAN; 460 if (ether_8021q_frame(mp, ifp, ifp, &qtag)) 461 return (true); 462 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 463 return (false); 464 } 465 466 /* 467 * Ethernet link layer output routine to send a raw frame to the device. 468 * 469 * This assumes that the 14 byte Ethernet header is present and contiguous 470 * in the first mbuf (if BRIDGE'ing). 471 */ 472 int 473 ether_output_frame(struct ifnet *ifp, struct mbuf *m) 474 { 475 if (ether_do_pcp(ifp, m) && !ether_set_pcp(&m, ifp, ifp->if_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 (__predict_false(m->m_len < ETHER_HDR_LEN)) { 540 /* Drivers should pullup and ensure the mbuf is valid */ 541 if_printf(ifp, "discard frame w/o leading ethernet " 542 "header (len %d pkt len %d)\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 if (!(ifp->if_capenable & IFCAP_HWSTATS)) 594 if_inc_counter(ifp, IFCOUNTER_IBYTES, m->m_pkthdr.len); 595 596 /* Allow monitor mode to claim this frame, after stats are updated. */ 597 if (ifp->if_flags & IFF_MONITOR) { 598 m_freem(m); 599 CURVNET_RESTORE(); 600 return; 601 } 602 603 /* Handle input from a lagg(4) port */ 604 if (ifp->if_type == IFT_IEEE8023ADLAG) { 605 KASSERT(lagg_input_ethernet_p != NULL, 606 ("%s: if_lagg not loaded!", __func__)); 607 m = (*lagg_input_ethernet_p)(ifp, m); 608 if (m != NULL) 609 ifp = m->m_pkthdr.rcvif; 610 else { 611 CURVNET_RESTORE(); 612 return; 613 } 614 } 615 616 /* 617 * If the hardware did not process an 802.1Q tag, do this now, 618 * to allow 802.1P priority frames to be passed to the main input 619 * path correctly. 620 */ 621 if ((m->m_flags & M_VLANTAG) == 0 && 622 ((etype == ETHERTYPE_VLAN) || (etype == ETHERTYPE_QINQ))) { 623 struct ether_vlan_header *evl; 624 625 if (m->m_len < sizeof(*evl) && 626 (m = m_pullup(m, sizeof(*evl))) == NULL) { 627 #ifdef DIAGNOSTIC 628 if_printf(ifp, "cannot pullup VLAN header\n"); 629 #endif 630 if_inc_counter(ifp, IFCOUNTER_IERRORS, 1); 631 CURVNET_RESTORE(); 632 return; 633 } 634 635 evl = mtod(m, struct ether_vlan_header *); 636 m->m_pkthdr.ether_vtag = ntohs(evl->evl_tag); 637 m->m_flags |= M_VLANTAG; 638 639 bcopy((char *)evl, (char *)evl + ETHER_VLAN_ENCAP_LEN, 640 ETHER_HDR_LEN - ETHER_TYPE_LEN); 641 m_adj(m, ETHER_VLAN_ENCAP_LEN); 642 eh = mtod(m, struct ether_header *); 643 } 644 645 M_SETFIB(m, ifp->if_fib); 646 647 /* Allow ng_ether(4) to claim this frame. */ 648 if (ifp->if_l2com != NULL) { 649 KASSERT(ng_ether_input_p != NULL, 650 ("%s: ng_ether_input_p is NULL", __func__)); 651 m->m_flags &= ~M_PROMISC; 652 (*ng_ether_input_p)(ifp, &m); 653 if (m == NULL) { 654 CURVNET_RESTORE(); 655 return; 656 } 657 eh = mtod(m, struct ether_header *); 658 } 659 660 /* 661 * Allow if_bridge(4) to claim this frame. 662 * 663 * The BRIDGE_INPUT() macro will update ifp if the bridge changed it 664 * and the frame should be delivered locally. 665 * 666 * If M_BRIDGE_INJECT is set, the packet was received directly by the 667 * bridge via netmap, so "ifp" is the bridge itself and the packet 668 * should be re-examined. 669 */ 670 if (ifp->if_bridge != NULL || (m->m_flags & M_BRIDGE_INJECT) != 0) { 671 m->m_flags &= ~M_PROMISC; 672 BRIDGE_INPUT(ifp, m); 673 if (m == NULL) { 674 CURVNET_RESTORE(); 675 return; 676 } 677 eh = mtod(m, struct ether_header *); 678 } 679 680 #if defined(INET) || defined(INET6) 681 /* 682 * Clear M_PROMISC on frame so that carp(4) will see it when the 683 * mbuf flows up to Layer 3. 684 * FreeBSD's implementation of carp(4) uses the inprotosw 685 * to dispatch IPPROTO_CARP. carp(4) also allocates its own 686 * Ethernet addresses of the form 00:00:5e:00:01:xx, which 687 * is outside the scope of the M_PROMISC test below. 688 * TODO: Maintain a hash table of ethernet addresses other than 689 * ether_dhost which may be active on this ifp. 690 */ 691 if (ifp->if_carp && (*carp_forus_p)(ifp, eh->ether_dhost)) { 692 m->m_flags &= ~M_PROMISC; 693 } else 694 #endif 695 { 696 /* 697 * If the frame received was not for our MAC address, set the 698 * M_PROMISC flag on the mbuf chain. The frame may need to 699 * be seen by the rest of the Ethernet input path in case of 700 * re-entry (e.g. bridge, vlan, netgraph) but should not be 701 * seen by upper protocol layers. 702 */ 703 if (!ETHER_IS_MULTICAST(eh->ether_dhost) && 704 bcmp(IF_LLADDR(ifp), eh->ether_dhost, ETHER_ADDR_LEN) != 0) 705 m->m_flags |= M_PROMISC; 706 } 707 708 ether_demux(ifp, m); 709 CURVNET_RESTORE(); 710 } 711 712 /* 713 * Ethernet input dispatch; by default, direct dispatch here regardless of 714 * global configuration. However, if RSS is enabled, hook up RSS affinity 715 * so that when deferred or hybrid dispatch is enabled, we can redistribute 716 * load based on RSS. 717 * 718 * XXXRW: Would be nice if the ifnet passed up a flag indicating whether or 719 * not it had already done work distribution via multi-queue. Then we could 720 * direct dispatch in the event load balancing was already complete and 721 * handle the case of interfaces with different capabilities better. 722 * 723 * XXXRW: Sort of want an M_DISTRIBUTED flag to avoid multiple distributions 724 * at multiple layers? 725 * 726 * XXXRW: For now, enable all this only if RSS is compiled in, although it 727 * works fine without RSS. Need to characterise the performance overhead 728 * of the detour through the netisr code in the event the result is always 729 * direct dispatch. 730 */ 731 static void 732 ether_nh_input(struct mbuf *m) 733 { 734 735 M_ASSERTPKTHDR(m); 736 KASSERT(m->m_pkthdr.rcvif != NULL, 737 ("%s: NULL interface pointer", __func__)); 738 ether_input_internal(m->m_pkthdr.rcvif, m); 739 } 740 741 static struct netisr_handler ether_nh = { 742 .nh_name = "ether", 743 .nh_handler = ether_nh_input, 744 .nh_proto = NETISR_ETHER, 745 #ifdef RSS 746 .nh_policy = NETISR_POLICY_CPU, 747 .nh_dispatch = NETISR_DISPATCH_DIRECT, 748 .nh_m2cpuid = rss_m2cpuid, 749 #else 750 .nh_policy = NETISR_POLICY_SOURCE, 751 .nh_dispatch = NETISR_DISPATCH_DIRECT, 752 #endif 753 }; 754 755 static void 756 ether_init(__unused void *arg) 757 { 758 759 netisr_register(ðer_nh); 760 } 761 SYSINIT(ether, SI_SUB_INIT_IF, SI_ORDER_ANY, ether_init, NULL); 762 763 static void 764 vnet_ether_init(const __unused void *arg) 765 { 766 struct pfil_head_args args; 767 768 args.pa_version = PFIL_VERSION; 769 args.pa_flags = PFIL_IN | PFIL_OUT; 770 args.pa_type = PFIL_TYPE_ETHERNET; 771 args.pa_headname = PFIL_ETHER_NAME; 772 V_link_pfil_head = pfil_head_register(&args); 773 774 #ifdef VIMAGE 775 netisr_register_vnet(ðer_nh); 776 #endif 777 } 778 VNET_SYSINIT(vnet_ether_init, SI_SUB_PROTO_IF, SI_ORDER_ANY, 779 vnet_ether_init, NULL); 780 781 #ifdef VIMAGE 782 static void 783 vnet_ether_pfil_destroy(const __unused void *arg) 784 { 785 786 pfil_head_unregister(V_link_pfil_head); 787 } 788 VNET_SYSUNINIT(vnet_ether_pfil_uninit, SI_SUB_PROTO_PFIL, SI_ORDER_ANY, 789 vnet_ether_pfil_destroy, NULL); 790 791 static void 792 vnet_ether_destroy(__unused void *arg) 793 { 794 795 netisr_unregister_vnet(ðer_nh); 796 } 797 VNET_SYSUNINIT(vnet_ether_uninit, SI_SUB_PROTO_IF, SI_ORDER_ANY, 798 vnet_ether_destroy, NULL); 799 #endif 800 801 static void 802 ether_input(struct ifnet *ifp, struct mbuf *m) 803 { 804 struct epoch_tracker et; 805 struct mbuf *mn; 806 bool needs_epoch; 807 808 needs_epoch = (ifp->if_flags & IFF_NEEDSEPOCH); 809 #ifdef INVARIANTS 810 /* 811 * This temporary code is here to prevent epoch unaware and unmarked 812 * drivers to panic the system. Once all drivers are taken care of, 813 * the whole INVARIANTS block should go away. 814 */ 815 if (!needs_epoch && !in_epoch(net_epoch_preempt)) { 816 static bool printedonce; 817 818 needs_epoch = true; 819 if (!printedonce) { 820 printedonce = true; 821 if_printf(ifp, "called %s w/o net epoch! " 822 "PLEASE file a bug report.", __func__); 823 #ifdef KDB 824 kdb_backtrace(); 825 #endif 826 } 827 } 828 #endif 829 830 /* 831 * The drivers are allowed to pass in a chain of packets linked with 832 * m_nextpkt. We split them up into separate packets here and pass 833 * them up. This allows the drivers to amortize the receive lock. 834 */ 835 CURVNET_SET_QUIET(ifp->if_vnet); 836 if (__predict_false(needs_epoch)) 837 NET_EPOCH_ENTER(et); 838 while (m) { 839 mn = m->m_nextpkt; 840 m->m_nextpkt = NULL; 841 842 /* 843 * We will rely on rcvif being set properly in the deferred 844 * context, so assert it is correct here. 845 */ 846 MPASS((m->m_pkthdr.csum_flags & CSUM_SND_TAG) == 0); 847 KASSERT(m->m_pkthdr.rcvif == ifp, ("%s: ifnet mismatch m %p " 848 "rcvif %p ifp %p", __func__, m, m->m_pkthdr.rcvif, ifp)); 849 netisr_dispatch(NETISR_ETHER, m); 850 m = mn; 851 } 852 if (__predict_false(needs_epoch)) 853 NET_EPOCH_EXIT(et); 854 CURVNET_RESTORE(); 855 } 856 857 /* 858 * Upper layer processing for a received Ethernet packet. 859 */ 860 void 861 ether_demux(struct ifnet *ifp, struct mbuf *m) 862 { 863 struct ether_header *eh; 864 int i, isr; 865 u_short ether_type; 866 867 NET_EPOCH_ASSERT(); 868 KASSERT(ifp != NULL, ("%s: NULL interface pointer", __func__)); 869 870 /* Do not grab PROMISC frames in case we are re-entered. */ 871 if (PFIL_HOOKED_IN(V_link_pfil_head) && !(m->m_flags & M_PROMISC)) { 872 i = pfil_mbuf_in(V_link_pfil_head, &m, ifp, NULL); 873 if (i != PFIL_PASS) 874 return; 875 } 876 877 eh = mtod(m, struct ether_header *); 878 ether_type = ntohs(eh->ether_type); 879 880 /* 881 * If this frame has a VLAN tag other than 0, call vlan_input() 882 * if its module is loaded. Otherwise, drop. 883 */ 884 if ((m->m_flags & M_VLANTAG) && 885 EVL_VLANOFTAG(m->m_pkthdr.ether_vtag) != 0) { 886 if (ifp->if_vlantrunk == NULL) { 887 if_inc_counter(ifp, IFCOUNTER_NOPROTO, 1); 888 m_freem(m); 889 return; 890 } 891 KASSERT(vlan_input_p != NULL,("%s: VLAN not loaded!", 892 __func__)); 893 /* Clear before possibly re-entering ether_input(). */ 894 m->m_flags &= ~M_PROMISC; 895 (*vlan_input_p)(ifp, m); 896 return; 897 } 898 899 /* 900 * Pass promiscuously received frames to the upper layer if the user 901 * requested this by setting IFF_PPROMISC. Otherwise, drop them. 902 */ 903 if ((ifp->if_flags & IFF_PPROMISC) == 0 && (m->m_flags & M_PROMISC)) { 904 m_freem(m); 905 return; 906 } 907 908 /* 909 * Reset layer specific mbuf flags to avoid confusing upper layers. 910 */ 911 m->m_flags &= ~M_VLANTAG; 912 m_clrprotoflags(m); 913 914 /* 915 * Dispatch frame to upper layer. 916 */ 917 switch (ether_type) { 918 #ifdef INET 919 case ETHERTYPE_IP: 920 isr = NETISR_IP; 921 break; 922 923 case ETHERTYPE_ARP: 924 if (ifp->if_flags & IFF_NOARP) { 925 /* Discard packet if ARP is disabled on interface */ 926 m_freem(m); 927 return; 928 } 929 isr = NETISR_ARP; 930 break; 931 #endif 932 #ifdef INET6 933 case ETHERTYPE_IPV6: 934 isr = NETISR_IPV6; 935 break; 936 #endif 937 default: 938 goto discard; 939 } 940 941 /* Strip off Ethernet header. */ 942 m_adj(m, ETHER_HDR_LEN); 943 944 netisr_dispatch(isr, m); 945 return; 946 947 discard: 948 /* 949 * Packet is to be discarded. If netgraph is present, 950 * hand the packet to it for last chance processing; 951 * otherwise dispose of it. 952 */ 953 if (ifp->if_l2com != NULL) { 954 KASSERT(ng_ether_input_orphan_p != NULL, 955 ("ng_ether_input_orphan_p is NULL")); 956 (*ng_ether_input_orphan_p)(ifp, m); 957 return; 958 } 959 m_freem(m); 960 } 961 962 /* 963 * Convert Ethernet address to printable (loggable) representation. 964 * This routine is for compatibility; it's better to just use 965 * 966 * printf("%6D", <pointer to address>, ":"); 967 * 968 * since there's no static buffer involved. 969 */ 970 char * 971 ether_sprintf(const u_char *ap) 972 { 973 static char etherbuf[18]; 974 snprintf(etherbuf, sizeof (etherbuf), "%6D", ap, ":"); 975 return (etherbuf); 976 } 977 978 /* 979 * Perform common duties while attaching to interface list 980 */ 981 void 982 ether_ifattach(struct ifnet *ifp, const u_int8_t *lla) 983 { 984 int i; 985 struct ifaddr *ifa; 986 struct sockaddr_dl *sdl; 987 988 ifp->if_addrlen = ETHER_ADDR_LEN; 989 ifp->if_hdrlen = ETHER_HDR_LEN; 990 ifp->if_mtu = ETHERMTU; 991 if_attach(ifp); 992 ifp->if_output = ether_output; 993 ifp->if_input = ether_input; 994 ifp->if_resolvemulti = ether_resolvemulti; 995 ifp->if_requestencap = ether_requestencap; 996 #ifdef VIMAGE 997 ifp->if_reassign = ether_reassign; 998 #endif 999 if (ifp->if_baudrate == 0) 1000 ifp->if_baudrate = IF_Mbps(10); /* just a default */ 1001 ifp->if_broadcastaddr = etherbroadcastaddr; 1002 1003 ifa = ifp->if_addr; 1004 KASSERT(ifa != NULL, ("%s: no lladdr!\n", __func__)); 1005 sdl = (struct sockaddr_dl *)ifa->ifa_addr; 1006 sdl->sdl_type = IFT_ETHER; 1007 sdl->sdl_alen = ifp->if_addrlen; 1008 bcopy(lla, LLADDR(sdl), ifp->if_addrlen); 1009 1010 if (ifp->if_hw_addr != NULL) 1011 bcopy(lla, ifp->if_hw_addr, ifp->if_addrlen); 1012 1013 bpfattach(ifp, DLT_EN10MB, ETHER_HDR_LEN); 1014 if (ng_ether_attach_p != NULL) 1015 (*ng_ether_attach_p)(ifp); 1016 1017 /* Announce Ethernet MAC address if non-zero. */ 1018 for (i = 0; i < ifp->if_addrlen; i++) 1019 if (lla[i] != 0) 1020 break; 1021 if (i != ifp->if_addrlen) 1022 if_printf(ifp, "Ethernet address: %6D\n", lla, ":"); 1023 1024 uuid_ether_add(LLADDR(sdl)); 1025 1026 /* Add necessary bits are setup; announce it now. */ 1027 EVENTHANDLER_INVOKE(ether_ifattach_event, ifp); 1028 if (IS_DEFAULT_VNET(curvnet)) 1029 devctl_notify("ETHERNET", ifp->if_xname, "IFATTACH", NULL); 1030 } 1031 1032 /* 1033 * Perform common duties while detaching an Ethernet interface 1034 */ 1035 void 1036 ether_ifdetach(struct ifnet *ifp) 1037 { 1038 struct sockaddr_dl *sdl; 1039 1040 sdl = (struct sockaddr_dl *)(ifp->if_addr->ifa_addr); 1041 uuid_ether_del(LLADDR(sdl)); 1042 1043 if (ifp->if_l2com != NULL) { 1044 KASSERT(ng_ether_detach_p != NULL, 1045 ("ng_ether_detach_p is NULL")); 1046 (*ng_ether_detach_p)(ifp); 1047 } 1048 1049 bpfdetach(ifp); 1050 if_detach(ifp); 1051 } 1052 1053 #ifdef VIMAGE 1054 void 1055 ether_reassign(struct ifnet *ifp, struct vnet *new_vnet, char *unused __unused) 1056 { 1057 1058 if (ifp->if_l2com != NULL) { 1059 KASSERT(ng_ether_detach_p != NULL, 1060 ("ng_ether_detach_p is NULL")); 1061 (*ng_ether_detach_p)(ifp); 1062 } 1063 1064 if (ng_ether_attach_p != NULL) { 1065 CURVNET_SET_QUIET(new_vnet); 1066 (*ng_ether_attach_p)(ifp); 1067 CURVNET_RESTORE(); 1068 } 1069 } 1070 #endif 1071 1072 SYSCTL_DECL(_net_link); 1073 SYSCTL_NODE(_net_link, IFT_ETHER, ether, CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 1074 "Ethernet"); 1075 1076 #if 0 1077 /* 1078 * This is for reference. We have a table-driven version 1079 * of the little-endian crc32 generator, which is faster 1080 * than the double-loop. 1081 */ 1082 uint32_t 1083 ether_crc32_le(const uint8_t *buf, size_t len) 1084 { 1085 size_t i; 1086 uint32_t crc; 1087 int bit; 1088 uint8_t data; 1089 1090 crc = 0xffffffff; /* initial value */ 1091 1092 for (i = 0; i < len; i++) { 1093 for (data = *buf++, bit = 0; bit < 8; bit++, data >>= 1) { 1094 carry = (crc ^ data) & 1; 1095 crc >>= 1; 1096 if (carry) 1097 crc = (crc ^ ETHER_CRC_POLY_LE); 1098 } 1099 } 1100 1101 return (crc); 1102 } 1103 #else 1104 uint32_t 1105 ether_crc32_le(const uint8_t *buf, size_t len) 1106 { 1107 static const uint32_t crctab[] = { 1108 0x00000000, 0x1db71064, 0x3b6e20c8, 0x26d930ac, 1109 0x76dc4190, 0x6b6b51f4, 0x4db26158, 0x5005713c, 1110 0xedb88320, 0xf00f9344, 0xd6d6a3e8, 0xcb61b38c, 1111 0x9b64c2b0, 0x86d3d2d4, 0xa00ae278, 0xbdbdf21c 1112 }; 1113 size_t i; 1114 uint32_t crc; 1115 1116 crc = 0xffffffff; /* initial value */ 1117 1118 for (i = 0; i < len; i++) { 1119 crc ^= buf[i]; 1120 crc = (crc >> 4) ^ crctab[crc & 0xf]; 1121 crc = (crc >> 4) ^ crctab[crc & 0xf]; 1122 } 1123 1124 return (crc); 1125 } 1126 #endif 1127 1128 uint32_t 1129 ether_crc32_be(const uint8_t *buf, size_t len) 1130 { 1131 size_t i; 1132 uint32_t crc, carry; 1133 int bit; 1134 uint8_t data; 1135 1136 crc = 0xffffffff; /* initial value */ 1137 1138 for (i = 0; i < len; i++) { 1139 for (data = *buf++, bit = 0; bit < 8; bit++, data >>= 1) { 1140 carry = ((crc & 0x80000000) ? 1 : 0) ^ (data & 0x01); 1141 crc <<= 1; 1142 if (carry) 1143 crc = (crc ^ ETHER_CRC_POLY_BE) | carry; 1144 } 1145 } 1146 1147 return (crc); 1148 } 1149 1150 int 1151 ether_ioctl(struct ifnet *ifp, u_long command, caddr_t data) 1152 { 1153 struct ifaddr *ifa = (struct ifaddr *) data; 1154 struct ifreq *ifr = (struct ifreq *) data; 1155 int error = 0; 1156 1157 switch (command) { 1158 case SIOCSIFADDR: 1159 ifp->if_flags |= IFF_UP; 1160 1161 switch (ifa->ifa_addr->sa_family) { 1162 #ifdef INET 1163 case AF_INET: 1164 ifp->if_init(ifp->if_softc); /* before arpwhohas */ 1165 arp_ifinit(ifp, ifa); 1166 break; 1167 #endif 1168 default: 1169 ifp->if_init(ifp->if_softc); 1170 break; 1171 } 1172 break; 1173 1174 case SIOCGIFADDR: 1175 bcopy(IF_LLADDR(ifp), &ifr->ifr_addr.sa_data[0], 1176 ETHER_ADDR_LEN); 1177 break; 1178 1179 case SIOCSIFMTU: 1180 /* 1181 * Set the interface MTU. 1182 */ 1183 if (ifr->ifr_mtu > ETHERMTU) { 1184 error = EINVAL; 1185 } else { 1186 ifp->if_mtu = ifr->ifr_mtu; 1187 } 1188 break; 1189 1190 case SIOCSLANPCP: 1191 error = priv_check(curthread, PRIV_NET_SETLANPCP); 1192 if (error != 0) 1193 break; 1194 if (ifr->ifr_lan_pcp > 7 && 1195 ifr->ifr_lan_pcp != IFNET_PCP_NONE) { 1196 error = EINVAL; 1197 } else { 1198 ifp->if_pcp = ifr->ifr_lan_pcp; 1199 /* broadcast event about PCP change */ 1200 EVENTHANDLER_INVOKE(ifnet_event, ifp, IFNET_EVENT_PCP); 1201 } 1202 break; 1203 1204 case SIOCGLANPCP: 1205 ifr->ifr_lan_pcp = ifp->if_pcp; 1206 break; 1207 1208 default: 1209 error = EINVAL; /* XXX netbsd has ENOTTY??? */ 1210 break; 1211 } 1212 return (error); 1213 } 1214 1215 static int 1216 ether_resolvemulti(struct ifnet *ifp, struct sockaddr **llsa, 1217 struct sockaddr *sa) 1218 { 1219 struct sockaddr_dl *sdl; 1220 #ifdef INET 1221 struct sockaddr_in *sin; 1222 #endif 1223 #ifdef INET6 1224 struct sockaddr_in6 *sin6; 1225 #endif 1226 u_char *e_addr; 1227 1228 switch(sa->sa_family) { 1229 case AF_LINK: 1230 /* 1231 * No mapping needed. Just check that it's a valid MC address. 1232 */ 1233 sdl = (struct sockaddr_dl *)sa; 1234 e_addr = LLADDR(sdl); 1235 if (!ETHER_IS_MULTICAST(e_addr)) 1236 return EADDRNOTAVAIL; 1237 *llsa = NULL; 1238 return 0; 1239 1240 #ifdef INET 1241 case AF_INET: 1242 sin = (struct sockaddr_in *)sa; 1243 if (!IN_MULTICAST(ntohl(sin->sin_addr.s_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_IP_MULTICAST(&sin->sin_addr, e_addr); 1249 *llsa = (struct sockaddr *)sdl; 1250 return 0; 1251 #endif 1252 #ifdef INET6 1253 case AF_INET6: 1254 sin6 = (struct sockaddr_in6 *)sa; 1255 if (IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr)) { 1256 /* 1257 * An IP6 address of 0 means listen to all 1258 * of the Ethernet multicast address used for IP6. 1259 * (This is used for multicast routers.) 1260 */ 1261 ifp->if_flags |= IFF_ALLMULTI; 1262 *llsa = NULL; 1263 return 0; 1264 } 1265 if (!IN6_IS_ADDR_MULTICAST(&sin6->sin6_addr)) 1266 return EADDRNOTAVAIL; 1267 sdl = link_init_sdl(ifp, *llsa, IFT_ETHER); 1268 sdl->sdl_alen = ETHER_ADDR_LEN; 1269 e_addr = LLADDR(sdl); 1270 ETHER_MAP_IPV6_MULTICAST(&sin6->sin6_addr, e_addr); 1271 *llsa = (struct sockaddr *)sdl; 1272 return 0; 1273 #endif 1274 1275 default: 1276 /* 1277 * Well, the text isn't quite right, but it's the name 1278 * that counts... 1279 */ 1280 return EAFNOSUPPORT; 1281 } 1282 } 1283 1284 static moduledata_t ether_mod = { 1285 .name = "ether", 1286 }; 1287 1288 void 1289 ether_vlan_mtap(struct bpf_if *bp, struct mbuf *m, void *data, u_int dlen) 1290 { 1291 struct ether_vlan_header vlan; 1292 struct mbuf mv, mb; 1293 1294 KASSERT((m->m_flags & M_VLANTAG) != 0, 1295 ("%s: vlan information not present", __func__)); 1296 KASSERT(m->m_len >= sizeof(struct ether_header), 1297 ("%s: mbuf not large enough for header", __func__)); 1298 bcopy(mtod(m, char *), &vlan, sizeof(struct ether_header)); 1299 vlan.evl_proto = vlan.evl_encap_proto; 1300 vlan.evl_encap_proto = htons(ETHERTYPE_VLAN); 1301 vlan.evl_tag = htons(m->m_pkthdr.ether_vtag); 1302 m->m_len -= sizeof(struct ether_header); 1303 m->m_data += sizeof(struct ether_header); 1304 /* 1305 * If a data link has been supplied by the caller, then we will need to 1306 * re-create a stack allocated mbuf chain with the following structure: 1307 * 1308 * (1) mbuf #1 will contain the supplied data link 1309 * (2) mbuf #2 will contain the vlan header 1310 * (3) mbuf #3 will contain the original mbuf's packet data 1311 * 1312 * Otherwise, submit the packet and vlan header via bpf_mtap2(). 1313 */ 1314 if (data != NULL) { 1315 mv.m_next = m; 1316 mv.m_data = (caddr_t)&vlan; 1317 mv.m_len = sizeof(vlan); 1318 mb.m_next = &mv; 1319 mb.m_data = data; 1320 mb.m_len = dlen; 1321 bpf_mtap(bp, &mb); 1322 } else 1323 bpf_mtap2(bp, &vlan, sizeof(vlan), m); 1324 m->m_len += sizeof(struct ether_header); 1325 m->m_data -= sizeof(struct ether_header); 1326 } 1327 1328 struct mbuf * 1329 ether_vlanencap_proto(struct mbuf *m, uint16_t tag, uint16_t proto) 1330 { 1331 struct ether_vlan_header *evl; 1332 1333 M_PREPEND(m, ETHER_VLAN_ENCAP_LEN, M_NOWAIT); 1334 if (m == NULL) 1335 return (NULL); 1336 /* M_PREPEND takes care of m_len, m_pkthdr.len for us */ 1337 1338 if (m->m_len < sizeof(*evl)) { 1339 m = m_pullup(m, sizeof(*evl)); 1340 if (m == NULL) 1341 return (NULL); 1342 } 1343 1344 /* 1345 * Transform the Ethernet header into an Ethernet header 1346 * with 802.1Q encapsulation. 1347 */ 1348 evl = mtod(m, struct ether_vlan_header *); 1349 bcopy((char *)evl + ETHER_VLAN_ENCAP_LEN, 1350 (char *)evl, ETHER_HDR_LEN - ETHER_TYPE_LEN); 1351 evl->evl_encap_proto = htons(proto); 1352 evl->evl_tag = htons(tag); 1353 return (m); 1354 } 1355 1356 void 1357 ether_bpf_mtap_if(struct ifnet *ifp, struct mbuf *m) 1358 { 1359 if (bpf_peers_present(ifp->if_bpf)) { 1360 M_ASSERTVALID(m); 1361 if ((m->m_flags & M_VLANTAG) != 0) 1362 ether_vlan_mtap(ifp->if_bpf, m, NULL, 0); 1363 else 1364 bpf_mtap(ifp->if_bpf, m); 1365 } 1366 } 1367 1368 static SYSCTL_NODE(_net_link, IFT_L2VLAN, vlan, CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 1369 "IEEE 802.1Q VLAN"); 1370 static SYSCTL_NODE(_net_link_vlan, PF_LINK, link, 1371 CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 1372 "for consistency"); 1373 1374 VNET_DEFINE_STATIC(int, soft_pad); 1375 #define V_soft_pad VNET(soft_pad) 1376 SYSCTL_INT(_net_link_vlan, OID_AUTO, soft_pad, CTLFLAG_RW | CTLFLAG_VNET, 1377 &VNET_NAME(soft_pad), 0, 1378 "pad short frames before tagging"); 1379 1380 /* 1381 * For now, make preserving PCP via an mbuf tag optional, as it increases 1382 * per-packet memory allocations and frees. In the future, it would be 1383 * preferable to reuse ether_vtag for this, or similar. 1384 */ 1385 VNET_DEFINE(int, vlan_mtag_pcp) = 0; 1386 #define V_vlan_mtag_pcp VNET(vlan_mtag_pcp) 1387 SYSCTL_INT(_net_link_vlan, OID_AUTO, mtag_pcp, CTLFLAG_RW | CTLFLAG_VNET, 1388 &VNET_NAME(vlan_mtag_pcp), 0, 1389 "Retain VLAN PCP information as packets are passed up the stack"); 1390 1391 static inline bool 1392 ether_do_pcp(struct ifnet *ifp, struct mbuf *m) 1393 { 1394 if (ifp->if_type == IFT_L2VLAN) 1395 return (false); 1396 if (ifp->if_pcp != IFNET_PCP_NONE || (m->m_flags & M_VLANTAG) != 0) 1397 return (true); 1398 if (V_vlan_mtag_pcp && 1399 m_tag_locate(m, MTAG_8021Q, MTAG_8021Q_PCP_OUT, NULL) != NULL) 1400 return (true); 1401 return (false); 1402 } 1403 1404 bool 1405 ether_8021q_frame(struct mbuf **mp, struct ifnet *ife, struct ifnet *p, 1406 const struct ether_8021q_tag *qtag) 1407 { 1408 struct m_tag *mtag; 1409 int n; 1410 uint16_t tag; 1411 uint8_t pcp = qtag->pcp; 1412 static const char pad[8]; /* just zeros */ 1413 1414 /* 1415 * Pad the frame to the minimum size allowed if told to. 1416 * This option is in accord with IEEE Std 802.1Q, 2003 Ed., 1417 * paragraph C.4.4.3.b. It can help to work around buggy 1418 * bridges that violate paragraph C.4.4.3.a from the same 1419 * document, i.e., fail to pad short frames after untagging. 1420 * E.g., a tagged frame 66 bytes long (incl. FCS) is OK, but 1421 * untagging it will produce a 62-byte frame, which is a runt 1422 * and requires padding. There are VLAN-enabled network 1423 * devices that just discard such runts instead or mishandle 1424 * them somehow. 1425 */ 1426 if (V_soft_pad && p->if_type == IFT_ETHER) { 1427 for (n = ETHERMIN + ETHER_HDR_LEN - (*mp)->m_pkthdr.len; 1428 n > 0; n -= sizeof(pad)) { 1429 if (!m_append(*mp, min(n, sizeof(pad)), pad)) 1430 break; 1431 } 1432 if (n > 0) { 1433 m_freem(*mp); 1434 *mp = NULL; 1435 if_printf(ife, "cannot pad short frame"); 1436 return (false); 1437 } 1438 } 1439 1440 /* 1441 * If PCP is set in mbuf, use it 1442 */ 1443 if ((*mp)->m_flags & M_VLANTAG) { 1444 pcp = EVL_PRIOFTAG((*mp)->m_pkthdr.ether_vtag); 1445 } 1446 1447 /* 1448 * If underlying interface can do VLAN tag insertion itself, 1449 * just pass the packet along. However, we need some way to 1450 * tell the interface where the packet came from so that it 1451 * knows how to find the VLAN tag to use, so we attach a 1452 * packet tag that holds it. 1453 */ 1454 if (V_vlan_mtag_pcp && (mtag = m_tag_locate(*mp, MTAG_8021Q, 1455 MTAG_8021Q_PCP_OUT, NULL)) != NULL) 1456 tag = EVL_MAKETAG(qtag->vid, *(uint8_t *)(mtag + 1), 0); 1457 else 1458 tag = EVL_MAKETAG(qtag->vid, pcp, 0); 1459 if ((p->if_capenable & IFCAP_VLAN_HWTAGGING) && 1460 (qtag->proto == ETHERTYPE_VLAN)) { 1461 (*mp)->m_pkthdr.ether_vtag = tag; 1462 (*mp)->m_flags |= M_VLANTAG; 1463 } else { 1464 *mp = ether_vlanencap_proto(*mp, tag, qtag->proto); 1465 if (*mp == NULL) { 1466 if_printf(ife, "unable to prepend 802.1Q header"); 1467 return (false); 1468 } 1469 (*mp)->m_flags &= ~M_VLANTAG; 1470 } 1471 return (true); 1472 } 1473 1474 /* 1475 * Allocate an address from the FreeBSD Foundation OUI. This uses a 1476 * cryptographic hash function on the containing jail's name, UUID and the 1477 * interface name to attempt to provide a unique but stable address. 1478 * Pseudo-interfaces which require a MAC address should use this function to 1479 * allocate non-locally-administered addresses. 1480 */ 1481 void 1482 ether_gen_addr_byname(const char *nameunit, struct ether_addr *hwaddr) 1483 { 1484 SHA1_CTX ctx; 1485 char *buf; 1486 char uuid[HOSTUUIDLEN + 1]; 1487 uint64_t addr; 1488 int i, sz; 1489 char digest[SHA1_RESULTLEN]; 1490 char jailname[MAXHOSTNAMELEN]; 1491 1492 getcredhostuuid(curthread->td_ucred, uuid, sizeof(uuid)); 1493 if (strncmp(uuid, DEFAULT_HOSTUUID, sizeof(uuid)) == 0) { 1494 /* Fall back to a random mac address. */ 1495 goto rando; 1496 } 1497 1498 /* If each (vnet) jail would also have a unique hostuuid this would not 1499 * be necessary. */ 1500 getjailname(curthread->td_ucred, jailname, sizeof(jailname)); 1501 sz = asprintf(&buf, M_TEMP, "%s-%s-%s", uuid, nameunit, 1502 jailname); 1503 if (sz < 0) { 1504 /* Fall back to a random mac address. */ 1505 goto rando; 1506 } 1507 1508 SHA1Init(&ctx); 1509 SHA1Update(&ctx, buf, sz); 1510 SHA1Final(digest, &ctx); 1511 free(buf, M_TEMP); 1512 1513 addr = ((digest[0] << 16) | (digest[1] << 8) | digest[2]) & 1514 OUI_FREEBSD_GENERATED_MASK; 1515 addr = OUI_FREEBSD(addr); 1516 for (i = 0; i < ETHER_ADDR_LEN; ++i) { 1517 hwaddr->octet[i] = addr >> ((ETHER_ADDR_LEN - i - 1) * 8) & 1518 0xFF; 1519 } 1520 1521 return; 1522 rando: 1523 arc4rand(hwaddr, sizeof(*hwaddr), 0); 1524 /* Unicast */ 1525 hwaddr->octet[0] &= 0xFE; 1526 /* Locally administered. */ 1527 hwaddr->octet[0] |= 0x02; 1528 } 1529 1530 void 1531 ether_gen_addr(struct ifnet *ifp, struct ether_addr *hwaddr) 1532 { 1533 ether_gen_addr_byname(if_name(ifp), hwaddr); 1534 } 1535 1536 DECLARE_MODULE(ether, ether_mod, SI_SUB_INIT_IF, SI_ORDER_ANY); 1537 MODULE_VERSION(ether, 1); 1538