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 bool (*bridge_member_ifaddrs_p)(void); 116 117 /* if_lagg(4) support */ 118 struct mbuf *(*lagg_input_ethernet_p)(struct ifnet *, struct mbuf *); 119 120 static const u_char etherbroadcastaddr[ETHER_ADDR_LEN] = 121 { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff }; 122 123 static int ether_resolvemulti(struct ifnet *, struct sockaddr **, 124 struct sockaddr *); 125 static int ether_requestencap(struct ifnet *, struct if_encap_req *); 126 127 static inline bool ether_do_pcp(struct ifnet *, struct mbuf *); 128 129 #define senderr(e) do { error = (e); goto bad;} while (0) 130 131 static void 132 update_mbuf_csumflags(struct mbuf *src, struct mbuf *dst) 133 { 134 int csum_flags = 0; 135 136 if (src->m_pkthdr.csum_flags & CSUM_IP) 137 csum_flags |= (CSUM_IP_CHECKED|CSUM_IP_VALID); 138 if (src->m_pkthdr.csum_flags & CSUM_DELAY_DATA) 139 csum_flags |= (CSUM_DATA_VALID|CSUM_PSEUDO_HDR); 140 if (src->m_pkthdr.csum_flags & CSUM_SCTP) 141 csum_flags |= CSUM_SCTP_VALID; 142 dst->m_pkthdr.csum_flags |= csum_flags; 143 if (csum_flags & CSUM_DATA_VALID) 144 dst->m_pkthdr.csum_data = 0xffff; 145 } 146 147 /* 148 * Handle link-layer encapsulation requests. 149 */ 150 static int 151 ether_requestencap(struct ifnet *ifp, struct if_encap_req *req) 152 { 153 struct ether_header *eh; 154 struct arphdr *ah; 155 uint16_t etype; 156 const u_char *lladdr; 157 158 if (req->rtype != IFENCAP_LL) 159 return (EOPNOTSUPP); 160 161 if (req->bufsize < ETHER_HDR_LEN) 162 return (ENOMEM); 163 164 eh = (struct ether_header *)req->buf; 165 lladdr = req->lladdr; 166 req->lladdr_off = 0; 167 168 switch (req->family) { 169 case AF_INET: 170 etype = htons(ETHERTYPE_IP); 171 break; 172 case AF_INET6: 173 etype = htons(ETHERTYPE_IPV6); 174 break; 175 case AF_ARP: 176 ah = (struct arphdr *)req->hdata; 177 ah->ar_hrd = htons(ARPHRD_ETHER); 178 179 switch(ntohs(ah->ar_op)) { 180 case ARPOP_REVREQUEST: 181 case ARPOP_REVREPLY: 182 etype = htons(ETHERTYPE_REVARP); 183 break; 184 case ARPOP_REQUEST: 185 case ARPOP_REPLY: 186 default: 187 etype = htons(ETHERTYPE_ARP); 188 break; 189 } 190 191 if (req->flags & IFENCAP_FLAG_BROADCAST) 192 lladdr = ifp->if_broadcastaddr; 193 break; 194 default: 195 return (EAFNOSUPPORT); 196 } 197 198 memcpy(&eh->ether_type, &etype, sizeof(eh->ether_type)); 199 memcpy(eh->ether_dhost, lladdr, ETHER_ADDR_LEN); 200 memcpy(eh->ether_shost, IF_LLADDR(ifp), ETHER_ADDR_LEN); 201 req->bufsize = sizeof(struct ether_header); 202 203 return (0); 204 } 205 206 static int 207 ether_resolve_addr(struct ifnet *ifp, struct mbuf *m, 208 const struct sockaddr *dst, struct route *ro, u_char *phdr, 209 uint32_t *pflags, struct llentry **plle) 210 { 211 uint32_t lleflags = 0; 212 int error = 0; 213 #if defined(INET) || defined(INET6) 214 struct ether_header *eh = (struct ether_header *)phdr; 215 uint16_t etype; 216 #endif 217 218 if (plle) 219 *plle = NULL; 220 221 switch (dst->sa_family) { 222 #ifdef INET 223 case AF_INET: 224 if ((m->m_flags & (M_BCAST | M_MCAST)) == 0) 225 error = arpresolve(ifp, 0, m, dst, phdr, &lleflags, 226 plle); 227 else { 228 if (m->m_flags & M_BCAST) 229 memcpy(eh->ether_dhost, ifp->if_broadcastaddr, 230 ETHER_ADDR_LEN); 231 else { 232 const struct in_addr *a; 233 a = &(((const struct sockaddr_in *)dst)->sin_addr); 234 ETHER_MAP_IP_MULTICAST(a, eh->ether_dhost); 235 } 236 etype = htons(ETHERTYPE_IP); 237 memcpy(&eh->ether_type, &etype, sizeof(etype)); 238 memcpy(eh->ether_shost, IF_LLADDR(ifp), ETHER_ADDR_LEN); 239 } 240 break; 241 #endif 242 #ifdef INET6 243 case AF_INET6: 244 if ((m->m_flags & M_MCAST) == 0) { 245 int af = RO_GET_FAMILY(ro, dst); 246 error = nd6_resolve(ifp, LLE_SF(af, 0), m, dst, phdr, 247 &lleflags, plle); 248 } else { 249 const struct in6_addr *a6; 250 a6 = &(((const struct sockaddr_in6 *)dst)->sin6_addr); 251 ETHER_MAP_IPV6_MULTICAST(a6, eh->ether_dhost); 252 etype = htons(ETHERTYPE_IPV6); 253 memcpy(&eh->ether_type, &etype, sizeof(etype)); 254 memcpy(eh->ether_shost, IF_LLADDR(ifp), ETHER_ADDR_LEN); 255 } 256 break; 257 #endif 258 default: 259 if_printf(ifp, "can't handle af%d\n", dst->sa_family); 260 if (m != NULL) 261 m_freem(m); 262 return (EAFNOSUPPORT); 263 } 264 265 if (error == EHOSTDOWN) { 266 if (ro != NULL && (ro->ro_flags & RT_HAS_GW) != 0) 267 error = EHOSTUNREACH; 268 } 269 270 if (error != 0) 271 return (error); 272 273 *pflags = RT_MAY_LOOP; 274 if (lleflags & LLE_IFADDR) 275 *pflags |= RT_L2_ME; 276 277 return (0); 278 } 279 280 /* 281 * Ethernet output routine. 282 * Encapsulate a packet of type family for the local net. 283 * Use trailer local net encapsulation if enough data in first 284 * packet leaves a multiple of 512 bytes of data in remainder. 285 */ 286 int 287 ether_output(struct ifnet *ifp, struct mbuf *m, 288 const struct sockaddr *dst, struct route *ro) 289 { 290 int error = 0; 291 char linkhdr[ETHER_HDR_LEN], *phdr; 292 struct ether_header *eh; 293 struct pf_mtag *t; 294 bool loop_copy; 295 int hlen; /* link layer header length */ 296 uint32_t pflags; 297 struct llentry *lle = NULL; 298 int addref = 0; 299 300 phdr = NULL; 301 pflags = 0; 302 if (ro != NULL) { 303 /* XXX BPF uses ro_prepend */ 304 if (ro->ro_prepend != NULL) { 305 phdr = ro->ro_prepend; 306 hlen = ro->ro_plen; 307 } else if (!(m->m_flags & (M_BCAST | M_MCAST))) { 308 if ((ro->ro_flags & RT_LLE_CACHE) != 0) { 309 lle = ro->ro_lle; 310 if (lle != NULL && 311 (lle->la_flags & LLE_VALID) == 0) { 312 LLE_FREE(lle); 313 lle = NULL; /* redundant */ 314 ro->ro_lle = NULL; 315 } 316 if (lle == NULL) { 317 /* if we lookup, keep cache */ 318 addref = 1; 319 } else 320 /* 321 * Notify LLE code that 322 * the entry was used 323 * by datapath. 324 */ 325 llentry_provide_feedback(lle); 326 } 327 if (lle != NULL) { 328 phdr = lle->r_linkdata; 329 hlen = lle->r_hdrlen; 330 pflags = lle->r_flags; 331 } 332 } 333 } 334 335 #ifdef MAC 336 error = mac_ifnet_check_transmit(ifp, m); 337 if (error) 338 senderr(error); 339 #endif 340 341 M_PROFILE(m); 342 if (ifp->if_flags & IFF_MONITOR) 343 senderr(ENETDOWN); 344 if (!((ifp->if_flags & IFF_UP) && 345 (ifp->if_drv_flags & IFF_DRV_RUNNING))) 346 senderr(ENETDOWN); 347 348 if (phdr == NULL) { 349 /* No prepend data supplied. Try to calculate ourselves. */ 350 phdr = linkhdr; 351 hlen = ETHER_HDR_LEN; 352 error = ether_resolve_addr(ifp, m, dst, ro, phdr, &pflags, 353 addref ? &lle : NULL); 354 if (addref && lle != NULL) 355 ro->ro_lle = lle; 356 if (error != 0) 357 return (error == EWOULDBLOCK ? 0 : error); 358 } 359 360 if ((pflags & RT_L2_ME) != 0) { 361 update_mbuf_csumflags(m, m); 362 return (if_simloop(ifp, m, RO_GET_FAMILY(ro, dst), 0)); 363 } 364 loop_copy = (pflags & RT_MAY_LOOP) != 0; 365 366 /* 367 * Add local net header. If no space in first mbuf, 368 * allocate another. 369 * 370 * Note that we do prepend regardless of RT_HAS_HEADER flag. 371 * This is done because BPF code shifts m_data pointer 372 * to the end of ethernet header prior to calling if_output(). 373 */ 374 M_PREPEND(m, hlen, M_NOWAIT); 375 if (m == NULL) 376 senderr(ENOBUFS); 377 if ((pflags & RT_HAS_HEADER) == 0) { 378 eh = mtod(m, struct ether_header *); 379 memcpy(eh, phdr, hlen); 380 } 381 382 /* 383 * If a simplex interface, and the packet is being sent to our 384 * Ethernet address or a broadcast address, loopback a copy. 385 * XXX To make a simplex device behave exactly like a duplex 386 * device, we should copy in the case of sending to our own 387 * ethernet address (thus letting the original actually appear 388 * on the wire). However, we don't do that here for security 389 * reasons and compatibility with the original behavior. 390 */ 391 if ((m->m_flags & M_BCAST) && loop_copy && (ifp->if_flags & IFF_SIMPLEX) && 392 ((t = pf_find_mtag(m)) == NULL || !t->routed)) { 393 struct mbuf *n; 394 395 /* 396 * Because if_simloop() modifies the packet, we need a 397 * writable copy through m_dup() instead of a readonly 398 * one as m_copy[m] would give us. The alternative would 399 * be to modify if_simloop() to handle the readonly mbuf, 400 * but performancewise it is mostly equivalent (trading 401 * extra data copying vs. extra locking). 402 * 403 * XXX This is a local workaround. A number of less 404 * often used kernel parts suffer from the same bug. 405 * See PR kern/105943 for a proposed general solution. 406 */ 407 if ((n = m_dup(m, M_NOWAIT)) != NULL) { 408 update_mbuf_csumflags(m, n); 409 (void)if_simloop(ifp, n, RO_GET_FAMILY(ro, dst), hlen); 410 } else 411 if_inc_counter(ifp, IFCOUNTER_IQDROPS, 1); 412 } 413 414 /* 415 * Bridges require special output handling. 416 */ 417 if (ifp->if_bridge) { 418 BRIDGE_OUTPUT(ifp, m, error); 419 return (error); 420 } 421 422 #if defined(INET) || defined(INET6) 423 if (ifp->if_carp && 424 (error = (*carp_output_p)(ifp, m, dst))) 425 goto bad; 426 #endif 427 428 /* Handle ng_ether(4) processing, if any */ 429 if (ifp->if_l2com != NULL) { 430 KASSERT(ng_ether_output_p != NULL, 431 ("ng_ether_output_p is NULL")); 432 if ((error = (*ng_ether_output_p)(ifp, &m)) != 0) { 433 bad: if (m != NULL) 434 m_freem(m); 435 return (error); 436 } 437 if (m == NULL) 438 return (0); 439 } 440 441 /* Continue with link-layer output */ 442 return ether_output_frame(ifp, m); 443 } 444 445 static bool 446 ether_set_pcp(struct mbuf **mp, struct ifnet *ifp, uint8_t pcp) 447 { 448 struct ether_8021q_tag qtag; 449 struct ether_header *eh; 450 451 eh = mtod(*mp, struct ether_header *); 452 if (eh->ether_type == htons(ETHERTYPE_VLAN) || 453 eh->ether_type == htons(ETHERTYPE_QINQ)) { 454 (*mp)->m_flags &= ~M_VLANTAG; 455 return (true); 456 } 457 458 qtag.vid = 0; 459 qtag.pcp = pcp; 460 qtag.proto = ETHERTYPE_VLAN; 461 if (ether_8021q_frame(mp, ifp, ifp, &qtag)) 462 return (true); 463 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 464 return (false); 465 } 466 467 /* 468 * Ethernet link layer output routine to send a raw frame to the device. 469 * 470 * This assumes that the 14 byte Ethernet header is present and contiguous 471 * in the first mbuf (if BRIDGE'ing). 472 */ 473 int 474 ether_output_frame(struct ifnet *ifp, struct mbuf *m) 475 { 476 if (ether_do_pcp(ifp, m) && !ether_set_pcp(&m, ifp, ifp->if_pcp)) 477 return (0); 478 479 if (PFIL_HOOKED_OUT(V_link_pfil_head)) 480 switch (pfil_mbuf_out(V_link_pfil_head, &m, ifp, NULL)) { 481 case PFIL_DROPPED: 482 return (EACCES); 483 case PFIL_CONSUMED: 484 return (0); 485 } 486 487 #ifdef EXPERIMENTAL 488 #if defined(INET6) && defined(INET) 489 /* draft-ietf-6man-ipv6only-flag */ 490 /* Catch ETHERTYPE_IP, and ETHERTYPE_[REV]ARP if we are v6-only. */ 491 if ((ND_IFINFO(ifp)->flags & ND6_IFF_IPV6_ONLY_MASK) != 0) { 492 struct ether_header *eh; 493 494 eh = mtod(m, struct ether_header *); 495 switch (ntohs(eh->ether_type)) { 496 case ETHERTYPE_IP: 497 case ETHERTYPE_ARP: 498 case ETHERTYPE_REVARP: 499 m_freem(m); 500 return (EAFNOSUPPORT); 501 /* NOTREACHED */ 502 break; 503 }; 504 } 505 #endif 506 #endif 507 508 /* 509 * Queue message on interface, update output statistics if successful, 510 * and start output if interface not yet active. 511 * 512 * If KMSAN is enabled, use it to verify that the data does not contain 513 * any uninitialized bytes. 514 */ 515 kmsan_check_mbuf(m, "ether_output"); 516 return ((ifp->if_transmit)(ifp, m)); 517 } 518 519 /* 520 * Process a received Ethernet packet; the packet is in the 521 * mbuf chain m with the ethernet header at the front. 522 */ 523 static void 524 ether_input_internal(struct ifnet *ifp, struct mbuf *m) 525 { 526 struct ether_header *eh; 527 u_short etype; 528 529 if ((ifp->if_flags & IFF_UP) == 0) { 530 m_freem(m); 531 return; 532 } 533 #ifdef DIAGNOSTIC 534 if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0) { 535 if_printf(ifp, "discard frame at !IFF_DRV_RUNNING\n"); 536 m_freem(m); 537 return; 538 } 539 #endif 540 if (__predict_false(m->m_len < ETHER_HDR_LEN)) { 541 /* Drivers should pullup and ensure the mbuf is valid */ 542 if_printf(ifp, "discard frame w/o leading ethernet " 543 "header (len %d pkt len %d)\n", 544 m->m_len, m->m_pkthdr.len); 545 if_inc_counter(ifp, IFCOUNTER_IERRORS, 1); 546 m_freem(m); 547 return; 548 } 549 eh = mtod(m, struct ether_header *); 550 etype = ntohs(eh->ether_type); 551 random_harvest_queue_ether(m, sizeof(*m)); 552 553 #ifdef EXPERIMENTAL 554 #if defined(INET6) && defined(INET) 555 /* draft-ietf-6man-ipv6only-flag */ 556 /* Catch ETHERTYPE_IP, and ETHERTYPE_[REV]ARP if we are v6-only. */ 557 if ((ND_IFINFO(ifp)->flags & ND6_IFF_IPV6_ONLY_MASK) != 0) { 558 switch (etype) { 559 case ETHERTYPE_IP: 560 case ETHERTYPE_ARP: 561 case ETHERTYPE_REVARP: 562 m_freem(m); 563 return; 564 /* NOTREACHED */ 565 break; 566 }; 567 } 568 #endif 569 #endif 570 571 CURVNET_SET_QUIET(ifp->if_vnet); 572 573 if (ETHER_IS_MULTICAST(eh->ether_dhost)) { 574 if (ETHER_IS_BROADCAST(eh->ether_dhost)) 575 m->m_flags |= M_BCAST; 576 else 577 m->m_flags |= M_MCAST; 578 if_inc_counter(ifp, IFCOUNTER_IMCASTS, 1); 579 } 580 581 #ifdef MAC 582 /* 583 * Tag the mbuf with an appropriate MAC label before any other 584 * consumers can get to it. 585 */ 586 mac_ifnet_create_mbuf(ifp, m); 587 #endif 588 589 /* 590 * Give bpf a chance at the packet. 591 */ 592 ETHER_BPF_MTAP(ifp, m); 593 594 if (!(ifp->if_capenable & IFCAP_HWSTATS)) 595 if_inc_counter(ifp, IFCOUNTER_IBYTES, m->m_pkthdr.len); 596 597 /* Allow monitor mode to claim this frame, after stats are updated. */ 598 if (ifp->if_flags & IFF_MONITOR) { 599 m_freem(m); 600 CURVNET_RESTORE(); 601 return; 602 } 603 604 /* Handle input from a lagg(4) port */ 605 if (ifp->if_type == IFT_IEEE8023ADLAG) { 606 KASSERT(lagg_input_ethernet_p != NULL, 607 ("%s: if_lagg not loaded!", __func__)); 608 m = (*lagg_input_ethernet_p)(ifp, m); 609 if (m != NULL) 610 ifp = m->m_pkthdr.rcvif; 611 else { 612 CURVNET_RESTORE(); 613 return; 614 } 615 } 616 617 /* 618 * If the hardware did not process an 802.1Q tag, do this now, 619 * to allow 802.1P priority frames to be passed to the main input 620 * path correctly. 621 */ 622 if ((m->m_flags & M_VLANTAG) == 0 && 623 ((etype == ETHERTYPE_VLAN) || (etype == ETHERTYPE_QINQ))) { 624 struct ether_vlan_header *evl; 625 626 if (m->m_len < sizeof(*evl) && 627 (m = m_pullup(m, sizeof(*evl))) == NULL) { 628 #ifdef DIAGNOSTIC 629 if_printf(ifp, "cannot pullup VLAN header\n"); 630 #endif 631 if_inc_counter(ifp, IFCOUNTER_IERRORS, 1); 632 CURVNET_RESTORE(); 633 return; 634 } 635 636 evl = mtod(m, struct ether_vlan_header *); 637 m->m_pkthdr.ether_vtag = ntohs(evl->evl_tag); 638 m->m_flags |= M_VLANTAG; 639 640 bcopy((char *)evl, (char *)evl + ETHER_VLAN_ENCAP_LEN, 641 ETHER_HDR_LEN - ETHER_TYPE_LEN); 642 m_adj(m, ETHER_VLAN_ENCAP_LEN); 643 eh = mtod(m, struct ether_header *); 644 } 645 646 M_SETFIB(m, ifp->if_fib); 647 648 /* Allow ng_ether(4) to claim this frame. */ 649 if (ifp->if_l2com != NULL) { 650 KASSERT(ng_ether_input_p != NULL, 651 ("%s: ng_ether_input_p is NULL", __func__)); 652 m->m_flags &= ~M_PROMISC; 653 (*ng_ether_input_p)(ifp, &m); 654 if (m == NULL) { 655 CURVNET_RESTORE(); 656 return; 657 } 658 eh = mtod(m, struct ether_header *); 659 } 660 661 /* 662 * Allow if_bridge(4) to claim this frame. 663 * 664 * The BRIDGE_INPUT() macro will update ifp if the bridge changed it 665 * and the frame should be delivered locally. 666 * 667 * If M_BRIDGE_INJECT is set, the packet was received directly by the 668 * bridge via netmap, so "ifp" is the bridge itself and the packet 669 * should be re-examined. 670 */ 671 if (ifp->if_bridge != NULL || (m->m_flags & M_BRIDGE_INJECT) != 0) { 672 m->m_flags &= ~M_PROMISC; 673 BRIDGE_INPUT(ifp, m); 674 if (m == NULL) { 675 CURVNET_RESTORE(); 676 return; 677 } 678 eh = mtod(m, struct ether_header *); 679 } 680 681 #if defined(INET) || defined(INET6) 682 /* 683 * Clear M_PROMISC on frame so that carp(4) will see it when the 684 * mbuf flows up to Layer 3. 685 * FreeBSD's implementation of carp(4) uses the inprotosw 686 * to dispatch IPPROTO_CARP. carp(4) also allocates its own 687 * Ethernet addresses of the form 00:00:5e:00:01:xx, which 688 * is outside the scope of the M_PROMISC test below. 689 * TODO: Maintain a hash table of ethernet addresses other than 690 * ether_dhost which may be active on this ifp. 691 */ 692 if (ifp->if_carp && (*carp_forus_p)(ifp, eh->ether_dhost)) { 693 m->m_flags &= ~M_PROMISC; 694 } else 695 #endif 696 { 697 /* 698 * If the frame received was not for our MAC address, set the 699 * M_PROMISC flag on the mbuf chain. The frame may need to 700 * be seen by the rest of the Ethernet input path in case of 701 * re-entry (e.g. bridge, vlan, netgraph) but should not be 702 * seen by upper protocol layers. 703 */ 704 if (!ETHER_IS_MULTICAST(eh->ether_dhost) && 705 bcmp(IF_LLADDR(ifp), eh->ether_dhost, ETHER_ADDR_LEN) != 0) 706 m->m_flags |= M_PROMISC; 707 } 708 709 ether_demux(ifp, m); 710 CURVNET_RESTORE(); 711 } 712 713 /* 714 * Ethernet input dispatch; by default, direct dispatch here regardless of 715 * global configuration. However, if RSS is enabled, hook up RSS affinity 716 * so that when deferred or hybrid dispatch is enabled, we can redistribute 717 * load based on RSS. 718 * 719 * XXXRW: Would be nice if the ifnet passed up a flag indicating whether or 720 * not it had already done work distribution via multi-queue. Then we could 721 * direct dispatch in the event load balancing was already complete and 722 * handle the case of interfaces with different capabilities better. 723 * 724 * XXXRW: Sort of want an M_DISTRIBUTED flag to avoid multiple distributions 725 * at multiple layers? 726 * 727 * XXXRW: For now, enable all this only if RSS is compiled in, although it 728 * works fine without RSS. Need to characterise the performance overhead 729 * of the detour through the netisr code in the event the result is always 730 * direct dispatch. 731 */ 732 static void 733 ether_nh_input(struct mbuf *m) 734 { 735 736 M_ASSERTPKTHDR(m); 737 KASSERT(m->m_pkthdr.rcvif != NULL, 738 ("%s: NULL interface pointer", __func__)); 739 ether_input_internal(m->m_pkthdr.rcvif, m); 740 } 741 742 static struct netisr_handler ether_nh = { 743 .nh_name = "ether", 744 .nh_handler = ether_nh_input, 745 .nh_proto = NETISR_ETHER, 746 #ifdef RSS 747 .nh_policy = NETISR_POLICY_CPU, 748 .nh_dispatch = NETISR_DISPATCH_DIRECT, 749 .nh_m2cpuid = rss_m2cpuid, 750 #else 751 .nh_policy = NETISR_POLICY_SOURCE, 752 .nh_dispatch = NETISR_DISPATCH_DIRECT, 753 #endif 754 }; 755 756 static void 757 ether_init(__unused void *arg) 758 { 759 760 netisr_register(ðer_nh); 761 } 762 SYSINIT(ether, SI_SUB_INIT_IF, SI_ORDER_ANY, ether_init, NULL); 763 764 static void 765 vnet_ether_init(const __unused void *arg) 766 { 767 struct pfil_head_args args; 768 769 args.pa_version = PFIL_VERSION; 770 args.pa_flags = PFIL_IN | PFIL_OUT; 771 args.pa_type = PFIL_TYPE_ETHERNET; 772 args.pa_headname = PFIL_ETHER_NAME; 773 V_link_pfil_head = pfil_head_register(&args); 774 775 #ifdef VIMAGE 776 netisr_register_vnet(ðer_nh); 777 #endif 778 } 779 VNET_SYSINIT(vnet_ether_init, SI_SUB_PROTO_IF, SI_ORDER_ANY, 780 vnet_ether_init, NULL); 781 782 #ifdef VIMAGE 783 static void 784 vnet_ether_pfil_destroy(const __unused void *arg) 785 { 786 787 pfil_head_unregister(V_link_pfil_head); 788 } 789 VNET_SYSUNINIT(vnet_ether_pfil_uninit, SI_SUB_PROTO_PFIL, SI_ORDER_ANY, 790 vnet_ether_pfil_destroy, NULL); 791 792 static void 793 vnet_ether_destroy(__unused void *arg) 794 { 795 796 netisr_unregister_vnet(ðer_nh); 797 } 798 VNET_SYSUNINIT(vnet_ether_uninit, SI_SUB_PROTO_IF, SI_ORDER_ANY, 799 vnet_ether_destroy, NULL); 800 #endif 801 802 static void 803 ether_input(struct ifnet *ifp, struct mbuf *m) 804 { 805 struct epoch_tracker et; 806 struct mbuf *mn; 807 bool needs_epoch; 808 809 needs_epoch = (ifp->if_flags & IFF_NEEDSEPOCH); 810 #ifdef INVARIANTS 811 /* 812 * This temporary code is here to prevent epoch unaware and unmarked 813 * drivers to panic the system. Once all drivers are taken care of, 814 * the whole INVARIANTS block should go away. 815 */ 816 if (!needs_epoch && !in_epoch(net_epoch_preempt)) { 817 static bool printedonce; 818 819 needs_epoch = true; 820 if (!printedonce) { 821 printedonce = true; 822 if_printf(ifp, "called %s w/o net epoch! " 823 "PLEASE file a bug report.", __func__); 824 #ifdef KDB 825 kdb_backtrace(); 826 #endif 827 } 828 } 829 #endif 830 831 /* 832 * The drivers are allowed to pass in a chain of packets linked with 833 * m_nextpkt. We split them up into separate packets here and pass 834 * them up. This allows the drivers to amortize the receive lock. 835 */ 836 CURVNET_SET_QUIET(ifp->if_vnet); 837 if (__predict_false(needs_epoch)) 838 NET_EPOCH_ENTER(et); 839 while (m) { 840 mn = m->m_nextpkt; 841 m->m_nextpkt = NULL; 842 843 /* 844 * We will rely on rcvif being set properly in the deferred 845 * context, so assert it is correct here. 846 */ 847 MPASS((m->m_pkthdr.csum_flags & CSUM_SND_TAG) == 0); 848 KASSERT(m->m_pkthdr.rcvif == ifp, ("%s: ifnet mismatch m %p " 849 "rcvif %p ifp %p", __func__, m, m->m_pkthdr.rcvif, ifp)); 850 netisr_dispatch(NETISR_ETHER, m); 851 m = mn; 852 } 853 if (__predict_false(needs_epoch)) 854 NET_EPOCH_EXIT(et); 855 CURVNET_RESTORE(); 856 } 857 858 /* 859 * Upper layer processing for a received Ethernet packet. 860 */ 861 void 862 ether_demux(struct ifnet *ifp, struct mbuf *m) 863 { 864 struct ether_header *eh; 865 int i, isr; 866 u_short ether_type; 867 868 NET_EPOCH_ASSERT(); 869 KASSERT(ifp != NULL, ("%s: NULL interface pointer", __func__)); 870 871 /* Do not grab PROMISC frames in case we are re-entered. */ 872 if (PFIL_HOOKED_IN(V_link_pfil_head) && !(m->m_flags & M_PROMISC)) { 873 i = pfil_mbuf_in(V_link_pfil_head, &m, ifp, NULL); 874 if (i != PFIL_PASS) 875 return; 876 } 877 878 eh = mtod(m, struct ether_header *); 879 ether_type = ntohs(eh->ether_type); 880 881 /* 882 * If this frame has a VLAN tag other than 0, call vlan_input() 883 * if its module is loaded. Otherwise, drop. 884 */ 885 if ((m->m_flags & M_VLANTAG) && 886 EVL_VLANOFTAG(m->m_pkthdr.ether_vtag) != 0) { 887 if (ifp->if_vlantrunk == NULL) { 888 if_inc_counter(ifp, IFCOUNTER_NOPROTO, 1); 889 m_freem(m); 890 return; 891 } 892 KASSERT(vlan_input_p != NULL,("%s: VLAN not loaded!", 893 __func__)); 894 /* Clear before possibly re-entering ether_input(). */ 895 m->m_flags &= ~M_PROMISC; 896 (*vlan_input_p)(ifp, m); 897 return; 898 } 899 900 /* 901 * Pass promiscuously received frames to the upper layer if the user 902 * requested this by setting IFF_PPROMISC. Otherwise, drop them. 903 */ 904 if ((ifp->if_flags & IFF_PPROMISC) == 0 && (m->m_flags & M_PROMISC)) { 905 m_freem(m); 906 return; 907 } 908 909 /* 910 * Reset layer specific mbuf flags to avoid confusing upper layers. 911 */ 912 m->m_flags &= ~M_VLANTAG; 913 m_clrprotoflags(m); 914 915 /* 916 * Dispatch frame to upper layer. 917 */ 918 switch (ether_type) { 919 #ifdef INET 920 case ETHERTYPE_IP: 921 isr = NETISR_IP; 922 break; 923 924 case ETHERTYPE_ARP: 925 if (ifp->if_flags & IFF_NOARP) { 926 /* Discard packet if ARP is disabled on interface */ 927 m_freem(m); 928 return; 929 } 930 isr = NETISR_ARP; 931 break; 932 #endif 933 #ifdef INET6 934 case ETHERTYPE_IPV6: 935 isr = NETISR_IPV6; 936 break; 937 #endif 938 default: 939 goto discard; 940 } 941 942 /* Strip off Ethernet header. */ 943 m_adj(m, ETHER_HDR_LEN); 944 945 netisr_dispatch(isr, m); 946 return; 947 948 discard: 949 /* 950 * Packet is to be discarded. If netgraph is present, 951 * hand the packet to it for last chance processing; 952 * otherwise dispose of it. 953 */ 954 if (ifp->if_l2com != NULL) { 955 KASSERT(ng_ether_input_orphan_p != NULL, 956 ("ng_ether_input_orphan_p is NULL")); 957 (*ng_ether_input_orphan_p)(ifp, m); 958 return; 959 } 960 m_freem(m); 961 } 962 963 /* 964 * Convert Ethernet address to printable (loggable) representation. 965 * This routine is for compatibility; it's better to just use 966 * 967 * printf("%6D", <pointer to address>, ":"); 968 * 969 * since there's no static buffer involved. 970 */ 971 char * 972 ether_sprintf(const u_char *ap) 973 { 974 static char etherbuf[18]; 975 snprintf(etherbuf, sizeof (etherbuf), "%6D", ap, ":"); 976 return (etherbuf); 977 } 978 979 /* 980 * Perform common duties while attaching to interface list 981 */ 982 void 983 ether_ifattach(struct ifnet *ifp, const u_int8_t *lla) 984 { 985 int i; 986 struct ifaddr *ifa; 987 struct sockaddr_dl *sdl; 988 989 ifp->if_addrlen = ETHER_ADDR_LEN; 990 ifp->if_hdrlen = ETHER_HDR_LEN; 991 ifp->if_mtu = ETHERMTU; 992 if_attach(ifp); 993 ifp->if_output = ether_output; 994 ifp->if_input = ether_input; 995 ifp->if_resolvemulti = ether_resolvemulti; 996 ifp->if_requestencap = ether_requestencap; 997 #ifdef VIMAGE 998 ifp->if_reassign = ether_reassign; 999 #endif 1000 if (ifp->if_baudrate == 0) 1001 ifp->if_baudrate = IF_Mbps(10); /* just a default */ 1002 ifp->if_broadcastaddr = etherbroadcastaddr; 1003 1004 ifa = ifp->if_addr; 1005 KASSERT(ifa != NULL, ("%s: no lladdr!\n", __func__)); 1006 sdl = (struct sockaddr_dl *)ifa->ifa_addr; 1007 sdl->sdl_type = IFT_ETHER; 1008 sdl->sdl_alen = ifp->if_addrlen; 1009 bcopy(lla, LLADDR(sdl), ifp->if_addrlen); 1010 1011 if (ifp->if_hw_addr != NULL) 1012 bcopy(lla, ifp->if_hw_addr, ifp->if_addrlen); 1013 1014 bpfattach(ifp, DLT_EN10MB, ETHER_HDR_LEN); 1015 if (ng_ether_attach_p != NULL) 1016 (*ng_ether_attach_p)(ifp); 1017 1018 /* Announce Ethernet MAC address if non-zero. */ 1019 for (i = 0; i < ifp->if_addrlen; i++) 1020 if (lla[i] != 0) 1021 break; 1022 if (i != ifp->if_addrlen) 1023 if_printf(ifp, "Ethernet address: %6D\n", lla, ":"); 1024 1025 uuid_ether_add(LLADDR(sdl)); 1026 1027 /* Add necessary bits are setup; announce it now. */ 1028 EVENTHANDLER_INVOKE(ether_ifattach_event, ifp); 1029 if (IS_DEFAULT_VNET(curvnet)) 1030 devctl_notify("ETHERNET", ifp->if_xname, "IFATTACH", NULL); 1031 } 1032 1033 /* 1034 * Perform common duties while detaching an Ethernet interface 1035 */ 1036 void 1037 ether_ifdetach(struct ifnet *ifp) 1038 { 1039 struct sockaddr_dl *sdl; 1040 1041 sdl = (struct sockaddr_dl *)(ifp->if_addr->ifa_addr); 1042 uuid_ether_del(LLADDR(sdl)); 1043 1044 if (ifp->if_l2com != NULL) { 1045 KASSERT(ng_ether_detach_p != NULL, 1046 ("ng_ether_detach_p is NULL")); 1047 (*ng_ether_detach_p)(ifp); 1048 } 1049 1050 bpfdetach(ifp); 1051 if_detach(ifp); 1052 } 1053 1054 #ifdef VIMAGE 1055 void 1056 ether_reassign(struct ifnet *ifp, struct vnet *new_vnet, char *unused __unused) 1057 { 1058 1059 if (ifp->if_l2com != NULL) { 1060 KASSERT(ng_ether_detach_p != NULL, 1061 ("ng_ether_detach_p is NULL")); 1062 (*ng_ether_detach_p)(ifp); 1063 } 1064 1065 if (ng_ether_attach_p != NULL) { 1066 CURVNET_SET_QUIET(new_vnet); 1067 (*ng_ether_attach_p)(ifp); 1068 CURVNET_RESTORE(); 1069 } 1070 } 1071 #endif 1072 1073 SYSCTL_DECL(_net_link); 1074 SYSCTL_NODE(_net_link, IFT_ETHER, ether, CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 1075 "Ethernet"); 1076 1077 #if 0 1078 /* 1079 * This is for reference. We have a table-driven version 1080 * of the little-endian crc32 generator, which is faster 1081 * than the double-loop. 1082 */ 1083 uint32_t 1084 ether_crc32_le(const uint8_t *buf, size_t len) 1085 { 1086 size_t i; 1087 uint32_t crc; 1088 int bit; 1089 uint8_t data; 1090 1091 crc = 0xffffffff; /* initial value */ 1092 1093 for (i = 0; i < len; i++) { 1094 for (data = *buf++, bit = 0; bit < 8; bit++, data >>= 1) { 1095 carry = (crc ^ data) & 1; 1096 crc >>= 1; 1097 if (carry) 1098 crc = (crc ^ ETHER_CRC_POLY_LE); 1099 } 1100 } 1101 1102 return (crc); 1103 } 1104 #else 1105 uint32_t 1106 ether_crc32_le(const uint8_t *buf, size_t len) 1107 { 1108 static const uint32_t crctab[] = { 1109 0x00000000, 0x1db71064, 0x3b6e20c8, 0x26d930ac, 1110 0x76dc4190, 0x6b6b51f4, 0x4db26158, 0x5005713c, 1111 0xedb88320, 0xf00f9344, 0xd6d6a3e8, 0xcb61b38c, 1112 0x9b64c2b0, 0x86d3d2d4, 0xa00ae278, 0xbdbdf21c 1113 }; 1114 size_t i; 1115 uint32_t crc; 1116 1117 crc = 0xffffffff; /* initial value */ 1118 1119 for (i = 0; i < len; i++) { 1120 crc ^= buf[i]; 1121 crc = (crc >> 4) ^ crctab[crc & 0xf]; 1122 crc = (crc >> 4) ^ crctab[crc & 0xf]; 1123 } 1124 1125 return (crc); 1126 } 1127 #endif 1128 1129 uint32_t 1130 ether_crc32_be(const uint8_t *buf, size_t len) 1131 { 1132 size_t i; 1133 uint32_t crc, carry; 1134 int bit; 1135 uint8_t data; 1136 1137 crc = 0xffffffff; /* initial value */ 1138 1139 for (i = 0; i < len; i++) { 1140 for (data = *buf++, bit = 0; bit < 8; bit++, data >>= 1) { 1141 carry = ((crc & 0x80000000) ? 1 : 0) ^ (data & 0x01); 1142 crc <<= 1; 1143 if (carry) 1144 crc = (crc ^ ETHER_CRC_POLY_BE) | carry; 1145 } 1146 } 1147 1148 return (crc); 1149 } 1150 1151 int 1152 ether_ioctl(struct ifnet *ifp, u_long command, caddr_t data) 1153 { 1154 struct ifaddr *ifa = (struct ifaddr *) data; 1155 struct ifreq *ifr = (struct ifreq *) data; 1156 int error = 0; 1157 1158 switch (command) { 1159 case SIOCSIFADDR: 1160 ifp->if_flags |= IFF_UP; 1161 1162 switch (ifa->ifa_addr->sa_family) { 1163 #ifdef INET 1164 case AF_INET: 1165 ifp->if_init(ifp->if_softc); /* before arpwhohas */ 1166 arp_ifinit(ifp, ifa); 1167 break; 1168 #endif 1169 default: 1170 ifp->if_init(ifp->if_softc); 1171 break; 1172 } 1173 break; 1174 1175 case SIOCGIFADDR: 1176 bcopy(IF_LLADDR(ifp), &ifr->ifr_addr.sa_data[0], 1177 ETHER_ADDR_LEN); 1178 break; 1179 1180 case SIOCSIFMTU: 1181 /* 1182 * Set the interface MTU. 1183 */ 1184 if (ifr->ifr_mtu > ETHERMTU) { 1185 error = EINVAL; 1186 } else { 1187 ifp->if_mtu = ifr->ifr_mtu; 1188 } 1189 break; 1190 1191 case SIOCSLANPCP: 1192 error = priv_check(curthread, PRIV_NET_SETLANPCP); 1193 if (error != 0) 1194 break; 1195 if (ifr->ifr_lan_pcp > 7 && 1196 ifr->ifr_lan_pcp != IFNET_PCP_NONE) { 1197 error = EINVAL; 1198 } else { 1199 ifp->if_pcp = ifr->ifr_lan_pcp; 1200 /* broadcast event about PCP change */ 1201 EVENTHANDLER_INVOKE(ifnet_event, ifp, IFNET_EVENT_PCP); 1202 } 1203 break; 1204 1205 case SIOCGLANPCP: 1206 ifr->ifr_lan_pcp = ifp->if_pcp; 1207 break; 1208 1209 default: 1210 error = EINVAL; /* XXX netbsd has ENOTTY??? */ 1211 break; 1212 } 1213 return (error); 1214 } 1215 1216 static int 1217 ether_resolvemulti(struct ifnet *ifp, struct sockaddr **llsa, 1218 struct sockaddr *sa) 1219 { 1220 struct sockaddr_dl *sdl; 1221 #ifdef INET 1222 struct sockaddr_in *sin; 1223 #endif 1224 #ifdef INET6 1225 struct sockaddr_in6 *sin6; 1226 #endif 1227 u_char *e_addr; 1228 1229 switch(sa->sa_family) { 1230 case AF_LINK: 1231 /* 1232 * No mapping needed. Just check that it's a valid MC address. 1233 */ 1234 sdl = (struct sockaddr_dl *)sa; 1235 e_addr = LLADDR(sdl); 1236 if (!ETHER_IS_MULTICAST(e_addr)) 1237 return EADDRNOTAVAIL; 1238 *llsa = NULL; 1239 return 0; 1240 1241 #ifdef INET 1242 case AF_INET: 1243 sin = (struct sockaddr_in *)sa; 1244 if (!IN_MULTICAST(ntohl(sin->sin_addr.s_addr))) 1245 return EADDRNOTAVAIL; 1246 sdl = link_init_sdl(ifp, *llsa, IFT_ETHER); 1247 sdl->sdl_alen = ETHER_ADDR_LEN; 1248 e_addr = LLADDR(sdl); 1249 ETHER_MAP_IP_MULTICAST(&sin->sin_addr, e_addr); 1250 *llsa = (struct sockaddr *)sdl; 1251 return 0; 1252 #endif 1253 #ifdef INET6 1254 case AF_INET6: 1255 sin6 = (struct sockaddr_in6 *)sa; 1256 if (IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr)) { 1257 /* 1258 * An IP6 address of 0 means listen to all 1259 * of the Ethernet multicast address used for IP6. 1260 * (This is used for multicast routers.) 1261 */ 1262 ifp->if_flags |= IFF_ALLMULTI; 1263 *llsa = NULL; 1264 return 0; 1265 } 1266 if (!IN6_IS_ADDR_MULTICAST(&sin6->sin6_addr)) 1267 return EADDRNOTAVAIL; 1268 sdl = link_init_sdl(ifp, *llsa, IFT_ETHER); 1269 sdl->sdl_alen = ETHER_ADDR_LEN; 1270 e_addr = LLADDR(sdl); 1271 ETHER_MAP_IPV6_MULTICAST(&sin6->sin6_addr, e_addr); 1272 *llsa = (struct sockaddr *)sdl; 1273 return 0; 1274 #endif 1275 1276 default: 1277 /* 1278 * Well, the text isn't quite right, but it's the name 1279 * that counts... 1280 */ 1281 return EAFNOSUPPORT; 1282 } 1283 } 1284 1285 static moduledata_t ether_mod = { 1286 .name = "ether", 1287 }; 1288 1289 void 1290 ether_vlan_mtap(struct bpf_if *bp, struct mbuf *m, void *data, u_int dlen) 1291 { 1292 struct ether_vlan_header vlan; 1293 struct mbuf mv, mb; 1294 1295 KASSERT((m->m_flags & M_VLANTAG) != 0, 1296 ("%s: vlan information not present", __func__)); 1297 KASSERT(m->m_len >= sizeof(struct ether_header), 1298 ("%s: mbuf not large enough for header", __func__)); 1299 bcopy(mtod(m, char *), &vlan, sizeof(struct ether_header)); 1300 vlan.evl_proto = vlan.evl_encap_proto; 1301 vlan.evl_encap_proto = htons(ETHERTYPE_VLAN); 1302 vlan.evl_tag = htons(m->m_pkthdr.ether_vtag); 1303 m->m_len -= sizeof(struct ether_header); 1304 m->m_data += sizeof(struct ether_header); 1305 /* 1306 * If a data link has been supplied by the caller, then we will need to 1307 * re-create a stack allocated mbuf chain with the following structure: 1308 * 1309 * (1) mbuf #1 will contain the supplied data link 1310 * (2) mbuf #2 will contain the vlan header 1311 * (3) mbuf #3 will contain the original mbuf's packet data 1312 * 1313 * Otherwise, submit the packet and vlan header via bpf_mtap2(). 1314 */ 1315 if (data != NULL) { 1316 mv.m_next = m; 1317 mv.m_data = (caddr_t)&vlan; 1318 mv.m_len = sizeof(vlan); 1319 mb.m_next = &mv; 1320 mb.m_data = data; 1321 mb.m_len = dlen; 1322 bpf_mtap(bp, &mb); 1323 } else 1324 bpf_mtap2(bp, &vlan, sizeof(vlan), m); 1325 m->m_len += sizeof(struct ether_header); 1326 m->m_data -= sizeof(struct ether_header); 1327 } 1328 1329 struct mbuf * 1330 ether_vlanencap_proto(struct mbuf *m, uint16_t tag, uint16_t proto) 1331 { 1332 struct ether_vlan_header *evl; 1333 1334 M_PREPEND(m, ETHER_VLAN_ENCAP_LEN, M_NOWAIT); 1335 if (m == NULL) 1336 return (NULL); 1337 /* M_PREPEND takes care of m_len, m_pkthdr.len for us */ 1338 1339 if (m->m_len < sizeof(*evl)) { 1340 m = m_pullup(m, sizeof(*evl)); 1341 if (m == NULL) 1342 return (NULL); 1343 } 1344 1345 /* 1346 * Transform the Ethernet header into an Ethernet header 1347 * with 802.1Q encapsulation. 1348 */ 1349 evl = mtod(m, struct ether_vlan_header *); 1350 bcopy((char *)evl + ETHER_VLAN_ENCAP_LEN, 1351 (char *)evl, ETHER_HDR_LEN - ETHER_TYPE_LEN); 1352 evl->evl_encap_proto = htons(proto); 1353 evl->evl_tag = htons(tag); 1354 return (m); 1355 } 1356 1357 void 1358 ether_bpf_mtap_if(struct ifnet *ifp, struct mbuf *m) 1359 { 1360 if (bpf_peers_present(ifp->if_bpf)) { 1361 M_ASSERTVALID(m); 1362 if ((m->m_flags & M_VLANTAG) != 0) 1363 ether_vlan_mtap(ifp->if_bpf, m, NULL, 0); 1364 else 1365 bpf_mtap(ifp->if_bpf, m); 1366 } 1367 } 1368 1369 static SYSCTL_NODE(_net_link, IFT_L2VLAN, vlan, CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 1370 "IEEE 802.1Q VLAN"); 1371 static SYSCTL_NODE(_net_link_vlan, PF_LINK, link, 1372 CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 1373 "for consistency"); 1374 1375 VNET_DEFINE_STATIC(int, soft_pad); 1376 #define V_soft_pad VNET(soft_pad) 1377 SYSCTL_INT(_net_link_vlan, OID_AUTO, soft_pad, CTLFLAG_RW | CTLFLAG_VNET, 1378 &VNET_NAME(soft_pad), 0, 1379 "pad short frames before tagging"); 1380 1381 /* 1382 * For now, make preserving PCP via an mbuf tag optional, as it increases 1383 * per-packet memory allocations and frees. In the future, it would be 1384 * preferable to reuse ether_vtag for this, or similar. 1385 */ 1386 VNET_DEFINE(int, vlan_mtag_pcp) = 0; 1387 #define V_vlan_mtag_pcp VNET(vlan_mtag_pcp) 1388 SYSCTL_INT(_net_link_vlan, OID_AUTO, mtag_pcp, CTLFLAG_RW | CTLFLAG_VNET, 1389 &VNET_NAME(vlan_mtag_pcp), 0, 1390 "Retain VLAN PCP information as packets are passed up the stack"); 1391 1392 static inline bool 1393 ether_do_pcp(struct ifnet *ifp, struct mbuf *m) 1394 { 1395 if (ifp->if_type == IFT_L2VLAN) 1396 return (false); 1397 if (ifp->if_pcp != IFNET_PCP_NONE || (m->m_flags & M_VLANTAG) != 0) 1398 return (true); 1399 if (V_vlan_mtag_pcp && 1400 m_tag_locate(m, MTAG_8021Q, MTAG_8021Q_PCP_OUT, NULL) != NULL) 1401 return (true); 1402 return (false); 1403 } 1404 1405 bool 1406 ether_8021q_frame(struct mbuf **mp, struct ifnet *ife, struct ifnet *p, 1407 const struct ether_8021q_tag *qtag) 1408 { 1409 struct m_tag *mtag; 1410 int n; 1411 uint16_t tag; 1412 uint8_t pcp = qtag->pcp; 1413 static const char pad[8]; /* just zeros */ 1414 1415 /* 1416 * Pad the frame to the minimum size allowed if told to. 1417 * This option is in accord with IEEE Std 802.1Q, 2003 Ed., 1418 * paragraph C.4.4.3.b. It can help to work around buggy 1419 * bridges that violate paragraph C.4.4.3.a from the same 1420 * document, i.e., fail to pad short frames after untagging. 1421 * E.g., a tagged frame 66 bytes long (incl. FCS) is OK, but 1422 * untagging it will produce a 62-byte frame, which is a runt 1423 * and requires padding. There are VLAN-enabled network 1424 * devices that just discard such runts instead or mishandle 1425 * them somehow. 1426 */ 1427 if (V_soft_pad && p->if_type == IFT_ETHER) { 1428 for (n = ETHERMIN + ETHER_HDR_LEN - (*mp)->m_pkthdr.len; 1429 n > 0; n -= sizeof(pad)) { 1430 if (!m_append(*mp, min(n, sizeof(pad)), pad)) 1431 break; 1432 } 1433 if (n > 0) { 1434 m_freem(*mp); 1435 *mp = NULL; 1436 if_printf(ife, "cannot pad short frame"); 1437 return (false); 1438 } 1439 } 1440 1441 /* 1442 * If PCP is set in mbuf, use it 1443 */ 1444 if ((*mp)->m_flags & M_VLANTAG) { 1445 pcp = EVL_PRIOFTAG((*mp)->m_pkthdr.ether_vtag); 1446 } 1447 1448 /* 1449 * If underlying interface can do VLAN tag insertion itself, 1450 * just pass the packet along. However, we need some way to 1451 * tell the interface where the packet came from so that it 1452 * knows how to find the VLAN tag to use, so we attach a 1453 * packet tag that holds it. 1454 */ 1455 if (V_vlan_mtag_pcp && (mtag = m_tag_locate(*mp, MTAG_8021Q, 1456 MTAG_8021Q_PCP_OUT, NULL)) != NULL) 1457 tag = EVL_MAKETAG(qtag->vid, *(uint8_t *)(mtag + 1), 0); 1458 else 1459 tag = EVL_MAKETAG(qtag->vid, pcp, 0); 1460 if ((p->if_capenable & IFCAP_VLAN_HWTAGGING) && 1461 (qtag->proto == ETHERTYPE_VLAN)) { 1462 (*mp)->m_pkthdr.ether_vtag = tag; 1463 (*mp)->m_flags |= M_VLANTAG; 1464 } else { 1465 *mp = ether_vlanencap_proto(*mp, tag, qtag->proto); 1466 if (*mp == NULL) { 1467 if_printf(ife, "unable to prepend 802.1Q header"); 1468 return (false); 1469 } 1470 (*mp)->m_flags &= ~M_VLANTAG; 1471 } 1472 return (true); 1473 } 1474 1475 /* 1476 * Allocate an address from the FreeBSD Foundation OUI. This uses a 1477 * cryptographic hash function on the containing jail's name, UUID and the 1478 * interface name to attempt to provide a unique but stable address. 1479 * Pseudo-interfaces which require a MAC address should use this function to 1480 * allocate non-locally-administered addresses. 1481 */ 1482 void 1483 ether_gen_addr_byname(const char *nameunit, struct ether_addr *hwaddr) 1484 { 1485 SHA1_CTX ctx; 1486 char *buf; 1487 char uuid[HOSTUUIDLEN + 1]; 1488 uint64_t addr; 1489 int i, sz; 1490 char digest[SHA1_RESULTLEN]; 1491 char jailname[MAXHOSTNAMELEN]; 1492 1493 getcredhostuuid(curthread->td_ucred, uuid, sizeof(uuid)); 1494 if (strncmp(uuid, DEFAULT_HOSTUUID, sizeof(uuid)) == 0) { 1495 /* Fall back to a random mac address. */ 1496 goto rando; 1497 } 1498 1499 /* If each (vnet) jail would also have a unique hostuuid this would not 1500 * be necessary. */ 1501 getjailname(curthread->td_ucred, jailname, sizeof(jailname)); 1502 sz = asprintf(&buf, M_TEMP, "%s-%s-%s", uuid, nameunit, 1503 jailname); 1504 if (sz < 0) { 1505 /* Fall back to a random mac address. */ 1506 goto rando; 1507 } 1508 1509 SHA1Init(&ctx); 1510 SHA1Update(&ctx, buf, sz); 1511 SHA1Final(digest, &ctx); 1512 free(buf, M_TEMP); 1513 1514 addr = ((digest[0] << 16) | (digest[1] << 8) | digest[2]) & 1515 OUI_FREEBSD_GENERATED_MASK; 1516 addr = OUI_FREEBSD(addr); 1517 for (i = 0; i < ETHER_ADDR_LEN; ++i) { 1518 hwaddr->octet[i] = addr >> ((ETHER_ADDR_LEN - i - 1) * 8) & 1519 0xFF; 1520 } 1521 1522 return; 1523 rando: 1524 arc4rand(hwaddr, sizeof(*hwaddr), 0); 1525 /* Unicast */ 1526 hwaddr->octet[0] &= 0xFE; 1527 /* Locally administered. */ 1528 hwaddr->octet[0] |= 0x02; 1529 } 1530 1531 void 1532 ether_gen_addr(struct ifnet *ifp, struct ether_addr *hwaddr) 1533 { 1534 ether_gen_addr_byname(if_name(ifp), hwaddr); 1535 } 1536 1537 DECLARE_MODULE(ether, ether_mod, SI_SUB_INIT_IF, SI_ORDER_ANY); 1538 MODULE_VERSION(ether, 1); 1539