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 /* if_bridge(4) support */ 110 void (*bridge_dn_p)(struct mbuf *, struct ifnet *); 111 bool (*bridge_same_p)(const void *, const void *); 112 void *(*bridge_get_softc_p)(struct ifnet *); 113 bool (*bridge_member_ifaddrs_p)(void); 114 115 /* if_lagg(4) support */ 116 struct mbuf *(*lagg_input_ethernet_p)(struct ifnet *, struct mbuf *); 117 118 static const u_char etherbroadcastaddr[ETHER_ADDR_LEN] = 119 { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff }; 120 121 static int ether_resolvemulti(struct ifnet *, struct sockaddr **, 122 struct sockaddr *); 123 static int ether_requestencap(struct ifnet *, struct if_encap_req *); 124 125 static inline bool ether_do_pcp(struct ifnet *, struct mbuf *); 126 127 #define senderr(e) do { error = (e); goto bad;} while (0) 128 129 static void 130 update_mbuf_csumflags(struct mbuf *src, struct mbuf *dst) 131 { 132 int csum_flags = 0; 133 134 if (src->m_pkthdr.csum_flags & CSUM_IP) 135 csum_flags |= (CSUM_IP_CHECKED|CSUM_IP_VALID); 136 if (src->m_pkthdr.csum_flags & CSUM_DELAY_DATA) 137 csum_flags |= (CSUM_DATA_VALID|CSUM_PSEUDO_HDR); 138 if (src->m_pkthdr.csum_flags & CSUM_SCTP) 139 csum_flags |= CSUM_SCTP_VALID; 140 dst->m_pkthdr.csum_flags |= csum_flags; 141 if (csum_flags & CSUM_DATA_VALID) 142 dst->m_pkthdr.csum_data = 0xffff; 143 } 144 145 /* 146 * Handle link-layer encapsulation requests. 147 */ 148 static int 149 ether_requestencap(struct ifnet *ifp, struct if_encap_req *req) 150 { 151 struct ether_header *eh; 152 struct arphdr *ah; 153 uint16_t etype; 154 const u_char *lladdr; 155 156 if (req->rtype != IFENCAP_LL) 157 return (EOPNOTSUPP); 158 159 if (req->bufsize < ETHER_HDR_LEN) 160 return (ENOMEM); 161 162 eh = (struct ether_header *)req->buf; 163 lladdr = req->lladdr; 164 req->lladdr_off = 0; 165 166 switch (req->family) { 167 case AF_INET: 168 etype = htons(ETHERTYPE_IP); 169 break; 170 case AF_INET6: 171 etype = htons(ETHERTYPE_IPV6); 172 break; 173 case AF_ARP: 174 ah = (struct arphdr *)req->hdata; 175 ah->ar_hrd = htons(ARPHRD_ETHER); 176 177 switch(ntohs(ah->ar_op)) { 178 case ARPOP_REVREQUEST: 179 case ARPOP_REVREPLY: 180 etype = htons(ETHERTYPE_REVARP); 181 break; 182 case ARPOP_REQUEST: 183 case ARPOP_REPLY: 184 default: 185 etype = htons(ETHERTYPE_ARP); 186 break; 187 } 188 189 if (req->flags & IFENCAP_FLAG_BROADCAST) 190 lladdr = ifp->if_broadcastaddr; 191 break; 192 default: 193 return (EAFNOSUPPORT); 194 } 195 196 memcpy(&eh->ether_type, &etype, sizeof(eh->ether_type)); 197 memcpy(eh->ether_dhost, lladdr, ETHER_ADDR_LEN); 198 memcpy(eh->ether_shost, IF_LLADDR(ifp), ETHER_ADDR_LEN); 199 req->bufsize = sizeof(struct ether_header); 200 201 return (0); 202 } 203 204 static int 205 ether_resolve_addr(struct ifnet *ifp, struct mbuf *m, 206 const struct sockaddr *dst, struct route *ro, u_char *phdr, 207 uint32_t *pflags, struct llentry **plle) 208 { 209 uint32_t lleflags = 0; 210 int error = 0; 211 #if defined(INET) || defined(INET6) 212 struct ether_header *eh = (struct ether_header *)phdr; 213 uint16_t etype; 214 #endif 215 216 if (plle) 217 *plle = NULL; 218 219 switch (dst->sa_family) { 220 #ifdef INET 221 case AF_INET: 222 if ((m->m_flags & (M_BCAST | M_MCAST)) == 0) 223 error = arpresolve(ifp, 0, m, dst, phdr, &lleflags, 224 plle); 225 else { 226 if (m->m_flags & M_BCAST) 227 memcpy(eh->ether_dhost, ifp->if_broadcastaddr, 228 ETHER_ADDR_LEN); 229 else { 230 const struct in_addr *a; 231 a = &(((const struct sockaddr_in *)dst)->sin_addr); 232 ETHER_MAP_IP_MULTICAST(a, eh->ether_dhost); 233 } 234 etype = htons(ETHERTYPE_IP); 235 memcpy(&eh->ether_type, &etype, sizeof(etype)); 236 memcpy(eh->ether_shost, IF_LLADDR(ifp), ETHER_ADDR_LEN); 237 } 238 break; 239 #endif 240 #ifdef INET6 241 case AF_INET6: 242 if ((m->m_flags & M_MCAST) == 0) { 243 int af = RO_GET_FAMILY(ro, dst); 244 error = nd6_resolve(ifp, LLE_SF(af, 0), m, dst, phdr, 245 &lleflags, plle); 246 } else { 247 const struct in6_addr *a6; 248 a6 = &(((const struct sockaddr_in6 *)dst)->sin6_addr); 249 ETHER_MAP_IPV6_MULTICAST(a6, eh->ether_dhost); 250 etype = htons(ETHERTYPE_IPV6); 251 memcpy(&eh->ether_type, &etype, sizeof(etype)); 252 memcpy(eh->ether_shost, IF_LLADDR(ifp), ETHER_ADDR_LEN); 253 } 254 break; 255 #endif 256 default: 257 if_printf(ifp, "can't handle af%d\n", dst->sa_family); 258 if (m != NULL) 259 m_freem(m); 260 return (EAFNOSUPPORT); 261 } 262 263 if (error == EHOSTDOWN) { 264 if (ro != NULL && (ro->ro_flags & RT_HAS_GW) != 0) 265 error = EHOSTUNREACH; 266 } 267 268 if (error != 0) 269 return (error); 270 271 *pflags = RT_MAY_LOOP; 272 if (lleflags & LLE_IFADDR) 273 *pflags |= RT_L2_ME; 274 275 return (0); 276 } 277 278 /* 279 * Ethernet output routine. 280 * Encapsulate a packet of type family for the local net. 281 * Use trailer local net encapsulation if enough data in first 282 * packet leaves a multiple of 512 bytes of data in remainder. 283 */ 284 int 285 ether_output(struct ifnet *ifp, struct mbuf *m, 286 const struct sockaddr *dst, struct route *ro) 287 { 288 int error = 0; 289 char linkhdr[ETHER_HDR_LEN], *phdr; 290 struct ether_header *eh; 291 struct pf_mtag *t; 292 bool loop_copy; 293 int hlen; /* link layer header length */ 294 uint32_t pflags; 295 struct llentry *lle = NULL; 296 int addref = 0; 297 298 phdr = NULL; 299 pflags = 0; 300 if (ro != NULL) { 301 /* XXX BPF uses ro_prepend */ 302 if (ro->ro_prepend != NULL) { 303 phdr = ro->ro_prepend; 304 hlen = ro->ro_plen; 305 } else if (!(m->m_flags & (M_BCAST | M_MCAST))) { 306 if ((ro->ro_flags & RT_LLE_CACHE) != 0) { 307 lle = ro->ro_lle; 308 if (lle != NULL && 309 (lle->la_flags & LLE_VALID) == 0) { 310 LLE_FREE(lle); 311 lle = NULL; /* redundant */ 312 ro->ro_lle = NULL; 313 } 314 if (lle == NULL) { 315 /* if we lookup, keep cache */ 316 addref = 1; 317 } else 318 /* 319 * Notify LLE code that 320 * the entry was used 321 * by datapath. 322 */ 323 llentry_provide_feedback(lle); 324 } 325 if (lle != NULL) { 326 phdr = lle->r_linkdata; 327 hlen = lle->r_hdrlen; 328 pflags = lle->r_flags; 329 } 330 } 331 } 332 333 #ifdef MAC 334 error = mac_ifnet_check_transmit(ifp, m); 335 if (error) 336 senderr(error); 337 #endif 338 339 M_PROFILE(m); 340 if (ifp->if_flags & IFF_MONITOR) 341 senderr(ENETDOWN); 342 if (!((ifp->if_flags & IFF_UP) && 343 (ifp->if_drv_flags & IFF_DRV_RUNNING))) 344 senderr(ENETDOWN); 345 346 if (phdr == NULL) { 347 /* No prepend data supplied. Try to calculate ourselves. */ 348 phdr = linkhdr; 349 hlen = ETHER_HDR_LEN; 350 error = ether_resolve_addr(ifp, m, dst, ro, phdr, &pflags, 351 addref ? &lle : NULL); 352 if (addref && lle != NULL) 353 ro->ro_lle = lle; 354 if (error != 0) 355 return (error == EWOULDBLOCK ? 0 : error); 356 } 357 358 if ((pflags & RT_L2_ME) != 0) { 359 update_mbuf_csumflags(m, m); 360 return (if_simloop(ifp, m, RO_GET_FAMILY(ro, dst), 0)); 361 } 362 loop_copy = (pflags & RT_MAY_LOOP) != 0; 363 364 /* 365 * Add local net header. If no space in first mbuf, 366 * allocate another. 367 * 368 * Note that we do prepend regardless of RT_HAS_HEADER flag. 369 * This is done because BPF code shifts m_data pointer 370 * to the end of ethernet header prior to calling if_output(). 371 */ 372 M_PREPEND(m, hlen, M_NOWAIT); 373 if (m == NULL) 374 senderr(ENOBUFS); 375 if ((pflags & RT_HAS_HEADER) == 0) { 376 eh = mtod(m, struct ether_header *); 377 memcpy(eh, phdr, hlen); 378 } 379 380 /* 381 * If a simplex interface, and the packet is being sent to our 382 * Ethernet address or a broadcast address, loopback a copy. 383 * XXX To make a simplex device behave exactly like a duplex 384 * device, we should copy in the case of sending to our own 385 * ethernet address (thus letting the original actually appear 386 * on the wire). However, we don't do that here for security 387 * reasons and compatibility with the original behavior. 388 */ 389 if ((m->m_flags & M_BCAST) && loop_copy && (ifp->if_flags & IFF_SIMPLEX) && 390 ((t = pf_find_mtag(m)) == NULL || !t->routed)) { 391 struct mbuf *n; 392 393 /* 394 * Because if_simloop() modifies the packet, we need a 395 * writable copy through m_dup() instead of a readonly 396 * one as m_copy[m] would give us. The alternative would 397 * be to modify if_simloop() to handle the readonly mbuf, 398 * but performancewise it is mostly equivalent (trading 399 * extra data copying vs. extra locking). 400 * 401 * XXX This is a local workaround. A number of less 402 * often used kernel parts suffer from the same bug. 403 * See PR kern/105943 for a proposed general solution. 404 */ 405 if ((n = m_dup(m, M_NOWAIT)) != NULL) { 406 update_mbuf_csumflags(m, n); 407 (void)if_simloop(ifp, n, RO_GET_FAMILY(ro, dst), hlen); 408 } else 409 if_inc_counter(ifp, IFCOUNTER_IQDROPS, 1); 410 } 411 412 /* 413 * Bridges require special output handling. 414 */ 415 if (ifp->if_bridge) { 416 BRIDGE_OUTPUT(ifp, m, error); 417 return (error); 418 } 419 420 #if defined(INET) || defined(INET6) 421 if (ifp->if_carp && 422 (error = (*carp_output_p)(ifp, m, dst))) 423 goto bad; 424 #endif 425 426 /* Handle ng_ether(4) processing, if any */ 427 if (ifp->if_l2com != NULL) { 428 KASSERT(ng_ether_output_p != NULL, 429 ("ng_ether_output_p is NULL")); 430 if ((error = (*ng_ether_output_p)(ifp, &m)) != 0) { 431 bad: if (m != NULL) 432 m_freem(m); 433 return (error); 434 } 435 if (m == NULL) 436 return (0); 437 } 438 439 /* Continue with link-layer output */ 440 return ether_output_frame(ifp, m); 441 } 442 443 static bool 444 ether_set_pcp(struct mbuf **mp, struct ifnet *ifp, uint8_t pcp) 445 { 446 struct ether_8021q_tag qtag; 447 struct ether_header *eh; 448 449 eh = mtod(*mp, struct ether_header *); 450 if (eh->ether_type == htons(ETHERTYPE_VLAN) || 451 eh->ether_type == htons(ETHERTYPE_QINQ)) { 452 (*mp)->m_flags &= ~M_VLANTAG; 453 return (true); 454 } 455 456 qtag.vid = 0; 457 qtag.pcp = pcp; 458 qtag.proto = ETHERTYPE_VLAN; 459 if (ether_8021q_frame(mp, ifp, ifp, &qtag)) 460 return (true); 461 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 462 return (false); 463 } 464 465 /* 466 * Ethernet link layer output routine to send a raw frame to the device. 467 * 468 * This assumes that the 14 byte Ethernet header is present and contiguous 469 * in the first mbuf (if BRIDGE'ing). 470 */ 471 int 472 ether_output_frame(struct ifnet *ifp, struct mbuf *m) 473 { 474 if (ether_do_pcp(ifp, m) && !ether_set_pcp(&m, ifp, ifp->if_pcp)) 475 return (0); 476 477 if (PFIL_HOOKED_OUT(V_link_pfil_head)) 478 switch (pfil_mbuf_out(V_link_pfil_head, &m, ifp, NULL)) { 479 case PFIL_DROPPED: 480 return (EACCES); 481 case PFIL_CONSUMED: 482 return (0); 483 } 484 485 #ifdef EXPERIMENTAL 486 #if defined(INET6) && defined(INET) 487 /* draft-ietf-6man-ipv6only-flag */ 488 /* Catch ETHERTYPE_IP, and ETHERTYPE_[REV]ARP if we are v6-only. */ 489 if ((ND_IFINFO(ifp)->flags & ND6_IFF_IPV6_ONLY_MASK) != 0) { 490 struct ether_header *eh; 491 492 eh = mtod(m, struct ether_header *); 493 switch (ntohs(eh->ether_type)) { 494 case ETHERTYPE_IP: 495 case ETHERTYPE_ARP: 496 case ETHERTYPE_REVARP: 497 m_freem(m); 498 return (EAFNOSUPPORT); 499 /* NOTREACHED */ 500 break; 501 }; 502 } 503 #endif 504 #endif 505 506 /* 507 * Queue message on interface, update output statistics if successful, 508 * and start output if interface not yet active. 509 * 510 * If KMSAN is enabled, use it to verify that the data does not contain 511 * any uninitialized bytes. 512 */ 513 kmsan_check_mbuf(m, "ether_output"); 514 return ((ifp->if_transmit)(ifp, m)); 515 } 516 517 /* 518 * Process a received Ethernet packet; the packet is in the 519 * mbuf chain m with the ethernet header at the front. 520 */ 521 static void 522 ether_input_internal(struct ifnet *ifp, struct mbuf *m) 523 { 524 struct ether_header *eh; 525 u_short etype; 526 527 if ((ifp->if_flags & IFF_UP) == 0) { 528 m_freem(m); 529 return; 530 } 531 #ifdef DIAGNOSTIC 532 if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0) { 533 if_printf(ifp, "discard frame at !IFF_DRV_RUNNING\n"); 534 m_freem(m); 535 return; 536 } 537 #endif 538 if (__predict_false(m->m_len < ETHER_HDR_LEN)) { 539 /* Drivers should pullup and ensure the mbuf is valid */ 540 if_printf(ifp, "discard frame w/o leading ethernet " 541 "header (len %d pkt len %d)\n", 542 m->m_len, m->m_pkthdr.len); 543 if_inc_counter(ifp, IFCOUNTER_IERRORS, 1); 544 m_freem(m); 545 return; 546 } 547 eh = mtod(m, struct ether_header *); 548 etype = ntohs(eh->ether_type); 549 random_harvest_queue_ether(m, sizeof(*m)); 550 551 #ifdef EXPERIMENTAL 552 #if defined(INET6) && defined(INET) 553 /* draft-ietf-6man-ipv6only-flag */ 554 /* Catch ETHERTYPE_IP, and ETHERTYPE_[REV]ARP if we are v6-only. */ 555 if ((ND_IFINFO(ifp)->flags & ND6_IFF_IPV6_ONLY_MASK) != 0) { 556 switch (etype) { 557 case ETHERTYPE_IP: 558 case ETHERTYPE_ARP: 559 case ETHERTYPE_REVARP: 560 m_freem(m); 561 return; 562 /* NOTREACHED */ 563 break; 564 }; 565 } 566 #endif 567 #endif 568 569 CURVNET_SET_QUIET(ifp->if_vnet); 570 571 if (ETHER_IS_MULTICAST(eh->ether_dhost)) { 572 if (ETHER_IS_BROADCAST(eh->ether_dhost)) 573 m->m_flags |= M_BCAST; 574 else 575 m->m_flags |= M_MCAST; 576 if_inc_counter(ifp, IFCOUNTER_IMCASTS, 1); 577 } 578 579 #ifdef MAC 580 /* 581 * Tag the mbuf with an appropriate MAC label before any other 582 * consumers can get to it. 583 */ 584 mac_ifnet_create_mbuf(ifp, m); 585 #endif 586 587 /* 588 * Give bpf a chance at the packet. 589 */ 590 ETHER_BPF_MTAP(ifp, m); 591 592 if (!(ifp->if_capenable & IFCAP_HWSTATS)) 593 if_inc_counter(ifp, IFCOUNTER_IBYTES, m->m_pkthdr.len); 594 595 /* Allow monitor mode to claim this frame, after stats are updated. */ 596 if (ifp->if_flags & IFF_MONITOR) { 597 m_freem(m); 598 CURVNET_RESTORE(); 599 return; 600 } 601 602 /* Handle input from a lagg(4) port */ 603 if (ifp->if_type == IFT_IEEE8023ADLAG) { 604 KASSERT(lagg_input_ethernet_p != NULL, 605 ("%s: if_lagg not loaded!", __func__)); 606 m = (*lagg_input_ethernet_p)(ifp, m); 607 if (m != NULL) 608 ifp = m->m_pkthdr.rcvif; 609 else { 610 CURVNET_RESTORE(); 611 return; 612 } 613 } 614 615 /* 616 * If the hardware did not process an 802.1Q tag, do this now, 617 * to allow 802.1P priority frames to be passed to the main input 618 * path correctly. 619 */ 620 if ((m->m_flags & M_VLANTAG) == 0 && 621 ((etype == ETHERTYPE_VLAN) || (etype == ETHERTYPE_QINQ))) { 622 struct ether_vlan_header *evl; 623 624 if (m->m_len < sizeof(*evl) && 625 (m = m_pullup(m, sizeof(*evl))) == NULL) { 626 #ifdef DIAGNOSTIC 627 if_printf(ifp, "cannot pullup VLAN header\n"); 628 #endif 629 if_inc_counter(ifp, IFCOUNTER_IERRORS, 1); 630 CURVNET_RESTORE(); 631 return; 632 } 633 634 evl = mtod(m, struct ether_vlan_header *); 635 m->m_pkthdr.ether_vtag = ntohs(evl->evl_tag); 636 m->m_flags |= M_VLANTAG; 637 638 bcopy((char *)evl, (char *)evl + ETHER_VLAN_ENCAP_LEN, 639 ETHER_HDR_LEN - ETHER_TYPE_LEN); 640 m_adj(m, ETHER_VLAN_ENCAP_LEN); 641 eh = mtod(m, struct ether_header *); 642 } 643 644 M_SETFIB(m, ifp->if_fib); 645 646 /* Allow ng_ether(4) to claim this frame. */ 647 if (ifp->if_l2com != NULL) { 648 KASSERT(ng_ether_input_p != NULL, 649 ("%s: ng_ether_input_p is NULL", __func__)); 650 m->m_flags &= ~M_PROMISC; 651 (*ng_ether_input_p)(ifp, &m); 652 if (m == NULL) { 653 CURVNET_RESTORE(); 654 return; 655 } 656 eh = mtod(m, struct ether_header *); 657 } 658 659 /* 660 * Allow if_bridge(4) to claim this frame. 661 * 662 * The BRIDGE_INPUT() macro will update ifp if the bridge changed it 663 * and the frame should be delivered locally. 664 * 665 * If M_BRIDGE_INJECT is set, the packet was received directly by the 666 * bridge via netmap, so "ifp" is the bridge itself and the packet 667 * should be re-examined. 668 */ 669 if (ifp->if_bridge != NULL || (m->m_flags & M_BRIDGE_INJECT) != 0) { 670 m->m_flags &= ~M_PROMISC; 671 BRIDGE_INPUT(ifp, m); 672 if (m == NULL) { 673 CURVNET_RESTORE(); 674 return; 675 } 676 eh = mtod(m, struct ether_header *); 677 } 678 679 #if defined(INET) || defined(INET6) 680 /* 681 * Clear M_PROMISC on frame so that carp(4) will see it when the 682 * mbuf flows up to Layer 3. 683 * FreeBSD's implementation of carp(4) uses the inprotosw 684 * to dispatch IPPROTO_CARP. carp(4) also allocates its own 685 * Ethernet addresses of the form 00:00:5e:00:01:xx, which 686 * is outside the scope of the M_PROMISC test below. 687 * TODO: Maintain a hash table of ethernet addresses other than 688 * ether_dhost which may be active on this ifp. 689 */ 690 if (ifp->if_carp && (*carp_forus_p)(ifp, eh->ether_dhost)) { 691 m->m_flags &= ~M_PROMISC; 692 } else 693 #endif 694 { 695 /* 696 * If the frame received was not for our MAC address, set the 697 * M_PROMISC flag on the mbuf chain. The frame may need to 698 * be seen by the rest of the Ethernet input path in case of 699 * re-entry (e.g. bridge, vlan, netgraph) but should not be 700 * seen by upper protocol layers. 701 */ 702 if (!ETHER_IS_MULTICAST(eh->ether_dhost) && 703 bcmp(IF_LLADDR(ifp), eh->ether_dhost, ETHER_ADDR_LEN) != 0) 704 m->m_flags |= M_PROMISC; 705 } 706 707 ether_demux(ifp, m); 708 CURVNET_RESTORE(); 709 } 710 711 /* 712 * Ethernet input dispatch; by default, direct dispatch here regardless of 713 * global configuration. However, if RSS is enabled, hook up RSS affinity 714 * so that when deferred or hybrid dispatch is enabled, we can redistribute 715 * load based on RSS. 716 * 717 * XXXRW: Would be nice if the ifnet passed up a flag indicating whether or 718 * not it had already done work distribution via multi-queue. Then we could 719 * direct dispatch in the event load balancing was already complete and 720 * handle the case of interfaces with different capabilities better. 721 * 722 * XXXRW: Sort of want an M_DISTRIBUTED flag to avoid multiple distributions 723 * at multiple layers? 724 * 725 * XXXRW: For now, enable all this only if RSS is compiled in, although it 726 * works fine without RSS. Need to characterise the performance overhead 727 * of the detour through the netisr code in the event the result is always 728 * direct dispatch. 729 */ 730 static void 731 ether_nh_input(struct mbuf *m) 732 { 733 734 M_ASSERTPKTHDR(m); 735 KASSERT(m->m_pkthdr.rcvif != NULL, 736 ("%s: NULL interface pointer", __func__)); 737 ether_input_internal(m->m_pkthdr.rcvif, m); 738 } 739 740 static struct netisr_handler ether_nh = { 741 .nh_name = "ether", 742 .nh_handler = ether_nh_input, 743 .nh_proto = NETISR_ETHER, 744 #ifdef RSS 745 .nh_policy = NETISR_POLICY_CPU, 746 .nh_dispatch = NETISR_DISPATCH_DIRECT, 747 .nh_m2cpuid = rss_m2cpuid, 748 #else 749 .nh_policy = NETISR_POLICY_SOURCE, 750 .nh_dispatch = NETISR_DISPATCH_DIRECT, 751 #endif 752 }; 753 754 static void 755 ether_init(__unused void *arg) 756 { 757 758 netisr_register(ðer_nh); 759 } 760 SYSINIT(ether, SI_SUB_INIT_IF, SI_ORDER_ANY, ether_init, NULL); 761 762 static void 763 vnet_ether_init(const __unused void *arg) 764 { 765 struct pfil_head_args args; 766 767 args.pa_version = PFIL_VERSION; 768 args.pa_flags = PFIL_IN | PFIL_OUT; 769 args.pa_type = PFIL_TYPE_ETHERNET; 770 args.pa_headname = PFIL_ETHER_NAME; 771 V_link_pfil_head = pfil_head_register(&args); 772 773 #ifdef VIMAGE 774 netisr_register_vnet(ðer_nh); 775 #endif 776 } 777 VNET_SYSINIT(vnet_ether_init, SI_SUB_PROTO_IF, SI_ORDER_ANY, 778 vnet_ether_init, NULL); 779 780 #ifdef VIMAGE 781 static void 782 vnet_ether_pfil_destroy(const __unused void *arg) 783 { 784 785 pfil_head_unregister(V_link_pfil_head); 786 } 787 VNET_SYSUNINIT(vnet_ether_pfil_uninit, SI_SUB_PROTO_PFIL, SI_ORDER_ANY, 788 vnet_ether_pfil_destroy, NULL); 789 790 static void 791 vnet_ether_destroy(__unused void *arg) 792 { 793 794 netisr_unregister_vnet(ðer_nh); 795 } 796 VNET_SYSUNINIT(vnet_ether_uninit, SI_SUB_PROTO_IF, SI_ORDER_ANY, 797 vnet_ether_destroy, NULL); 798 #endif 799 800 static void 801 ether_input(struct ifnet *ifp, struct mbuf *m) 802 { 803 struct epoch_tracker et; 804 struct mbuf *mn; 805 bool needs_epoch; 806 807 needs_epoch = (ifp->if_flags & IFF_NEEDSEPOCH); 808 #ifdef INVARIANTS 809 /* 810 * This temporary code is here to prevent epoch unaware and unmarked 811 * drivers to panic the system. Once all drivers are taken care of, 812 * the whole INVARIANTS block should go away. 813 */ 814 if (!needs_epoch && !in_epoch(net_epoch_preempt)) { 815 static bool printedonce; 816 817 needs_epoch = true; 818 if (!printedonce) { 819 printedonce = true; 820 if_printf(ifp, "called %s w/o net epoch! " 821 "PLEASE file a bug report.", __func__); 822 #ifdef KDB 823 kdb_backtrace(); 824 #endif 825 } 826 } 827 #endif 828 829 /* 830 * The drivers are allowed to pass in a chain of packets linked with 831 * m_nextpkt. We split them up into separate packets here and pass 832 * them up. This allows the drivers to amortize the receive lock. 833 */ 834 CURVNET_SET_QUIET(ifp->if_vnet); 835 if (__predict_false(needs_epoch)) 836 NET_EPOCH_ENTER(et); 837 while (m) { 838 mn = m->m_nextpkt; 839 m->m_nextpkt = NULL; 840 841 /* 842 * We will rely on rcvif being set properly in the deferred 843 * context, so assert it is correct here. 844 */ 845 MPASS((m->m_pkthdr.csum_flags & CSUM_SND_TAG) == 0); 846 KASSERT(m->m_pkthdr.rcvif == ifp, ("%s: ifnet mismatch m %p " 847 "rcvif %p ifp %p", __func__, m, m->m_pkthdr.rcvif, ifp)); 848 netisr_dispatch(NETISR_ETHER, m); 849 m = mn; 850 } 851 if (__predict_false(needs_epoch)) 852 NET_EPOCH_EXIT(et); 853 CURVNET_RESTORE(); 854 } 855 856 /* 857 * Upper layer processing for a received Ethernet packet. 858 */ 859 void 860 ether_demux(struct ifnet *ifp, struct mbuf *m) 861 { 862 struct ether_header *eh; 863 int i, isr; 864 u_short ether_type; 865 866 NET_EPOCH_ASSERT(); 867 KASSERT(ifp != NULL, ("%s: NULL interface pointer", __func__)); 868 869 /* Do not grab PROMISC frames in case we are re-entered. */ 870 if (PFIL_HOOKED_IN(V_link_pfil_head) && !(m->m_flags & M_PROMISC)) { 871 i = pfil_mbuf_in(V_link_pfil_head, &m, ifp, NULL); 872 if (i != PFIL_PASS) 873 return; 874 } 875 876 eh = mtod(m, struct ether_header *); 877 ether_type = ntohs(eh->ether_type); 878 879 /* 880 * If this frame has a VLAN tag other than 0, call vlan_input() 881 * if its module is loaded. Otherwise, drop. 882 */ 883 if ((m->m_flags & M_VLANTAG) && 884 EVL_VLANOFTAG(m->m_pkthdr.ether_vtag) != 0) { 885 if (ifp->if_vlantrunk == NULL) { 886 if_inc_counter(ifp, IFCOUNTER_NOPROTO, 1); 887 m_freem(m); 888 return; 889 } 890 KASSERT(vlan_input_p != NULL,("%s: VLAN not loaded!", 891 __func__)); 892 /* Clear before possibly re-entering ether_input(). */ 893 m->m_flags &= ~M_PROMISC; 894 (*vlan_input_p)(ifp, m); 895 return; 896 } 897 898 /* 899 * Pass promiscuously received frames to the upper layer if the user 900 * requested this by setting IFF_PPROMISC. Otherwise, drop them. 901 */ 902 if ((ifp->if_flags & IFF_PPROMISC) == 0 && (m->m_flags & M_PROMISC)) { 903 m_freem(m); 904 return; 905 } 906 907 /* 908 * Reset layer specific mbuf flags to avoid confusing upper layers. 909 */ 910 m->m_flags &= ~M_VLANTAG; 911 m_clrprotoflags(m); 912 913 /* 914 * Dispatch frame to upper layer. 915 */ 916 switch (ether_type) { 917 #ifdef INET 918 case ETHERTYPE_IP: 919 isr = NETISR_IP; 920 break; 921 922 case ETHERTYPE_ARP: 923 if (ifp->if_flags & IFF_NOARP) { 924 /* Discard packet if ARP is disabled on interface */ 925 m_freem(m); 926 return; 927 } 928 isr = NETISR_ARP; 929 break; 930 #endif 931 #ifdef INET6 932 case ETHERTYPE_IPV6: 933 isr = NETISR_IPV6; 934 break; 935 #endif 936 default: 937 goto discard; 938 } 939 940 /* Strip off Ethernet header. */ 941 m_adj(m, ETHER_HDR_LEN); 942 943 netisr_dispatch(isr, m); 944 return; 945 946 discard: 947 /* 948 * Packet is to be discarded. If netgraph is present, 949 * hand the packet to it for last chance processing; 950 * otherwise dispose of it. 951 */ 952 if (ifp->if_l2com != NULL) { 953 KASSERT(ng_ether_input_orphan_p != NULL, 954 ("ng_ether_input_orphan_p is NULL")); 955 (*ng_ether_input_orphan_p)(ifp, m); 956 return; 957 } 958 m_freem(m); 959 } 960 961 /* 962 * Convert Ethernet address to printable (loggable) representation. 963 * This routine is for compatibility; it's better to just use 964 * 965 * printf("%6D", <pointer to address>, ":"); 966 * 967 * since there's no static buffer involved. 968 */ 969 char * 970 ether_sprintf(const u_char *ap) 971 { 972 static char etherbuf[18]; 973 snprintf(etherbuf, sizeof (etherbuf), "%6D", ap, ":"); 974 return (etherbuf); 975 } 976 977 /* 978 * Perform common duties while attaching to interface list 979 */ 980 void 981 ether_ifattach(struct ifnet *ifp, const u_int8_t *lla) 982 { 983 int i; 984 struct ifaddr *ifa; 985 struct sockaddr_dl *sdl; 986 987 ifp->if_addrlen = ETHER_ADDR_LEN; 988 ifp->if_hdrlen = (ifp->if_capabilities & IFCAP_VLAN_MTU) != 0 ? 989 ETHER_HDR_LEN + ETHER_VLAN_ENCAP_LEN : 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