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 VNET_DEFINE(pfil_head_t, link_pfil_head); /* Packet filter hooks */ 96 97 /* netgraph node hooks for ng_ether(4) */ 98 void (*ng_ether_input_p)(struct ifnet *ifp, struct mbuf **mp); 99 void (*ng_ether_input_orphan_p)(struct ifnet *ifp, struct mbuf *m); 100 int (*ng_ether_output_p)(struct ifnet *ifp, struct mbuf **mp); 101 void (*ng_ether_attach_p)(struct ifnet *ifp); 102 void (*ng_ether_detach_p)(struct ifnet *ifp); 103 104 /* if_bridge(4) support */ 105 void (*bridge_dn_p)(struct mbuf *, struct ifnet *); 106 bool (*bridge_same_p)(const void *, const void *); 107 void *(*bridge_get_softc_p)(struct ifnet *); 108 bool (*bridge_member_ifaddrs_p)(void); 109 110 /* if_lagg(4) support */ 111 struct mbuf *(*lagg_input_ethernet_p)(struct ifnet *, struct mbuf *); 112 113 static const u_char etherbroadcastaddr[ETHER_ADDR_LEN] = 114 { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff }; 115 116 static int ether_resolvemulti(struct ifnet *, struct sockaddr **, 117 struct sockaddr *); 118 static int ether_requestencap(struct ifnet *, struct if_encap_req *); 119 120 static inline bool ether_do_pcp(struct ifnet *, struct mbuf *); 121 122 #define senderr(e) do { error = (e); goto bad;} while (0) 123 124 static void 125 update_mbuf_csumflags(struct mbuf *src, struct mbuf *dst) 126 { 127 int csum_flags = 0; 128 129 if (src->m_pkthdr.csum_flags & CSUM_IP) 130 csum_flags |= (CSUM_IP_CHECKED|CSUM_IP_VALID); 131 if (src->m_pkthdr.csum_flags & CSUM_DELAY_DATA) 132 csum_flags |= (CSUM_DATA_VALID|CSUM_PSEUDO_HDR); 133 if (src->m_pkthdr.csum_flags & CSUM_SCTP) 134 csum_flags |= CSUM_SCTP_VALID; 135 dst->m_pkthdr.csum_flags |= csum_flags; 136 if (csum_flags & CSUM_DATA_VALID) 137 dst->m_pkthdr.csum_data = 0xffff; 138 } 139 140 /* 141 * Handle link-layer encapsulation requests. 142 */ 143 static int 144 ether_requestencap(struct ifnet *ifp, struct if_encap_req *req) 145 { 146 struct ether_header *eh; 147 struct arphdr *ah; 148 uint16_t etype; 149 const u_char *lladdr; 150 151 if (req->rtype != IFENCAP_LL) 152 return (EOPNOTSUPP); 153 154 if (req->bufsize < ETHER_HDR_LEN) 155 return (ENOMEM); 156 157 eh = (struct ether_header *)req->buf; 158 lladdr = req->lladdr; 159 req->lladdr_off = 0; 160 161 switch (req->family) { 162 case AF_INET: 163 etype = htons(ETHERTYPE_IP); 164 break; 165 case AF_INET6: 166 etype = htons(ETHERTYPE_IPV6); 167 break; 168 case AF_ARP: 169 ah = (struct arphdr *)req->hdata; 170 ah->ar_hrd = htons(ARPHRD_ETHER); 171 172 switch(ntohs(ah->ar_op)) { 173 case ARPOP_REVREQUEST: 174 case ARPOP_REVREPLY: 175 etype = htons(ETHERTYPE_REVARP); 176 break; 177 case ARPOP_REQUEST: 178 case ARPOP_REPLY: 179 default: 180 etype = htons(ETHERTYPE_ARP); 181 break; 182 } 183 184 if (req->flags & IFENCAP_FLAG_BROADCAST) 185 lladdr = ifp->if_broadcastaddr; 186 break; 187 default: 188 return (EAFNOSUPPORT); 189 } 190 191 memcpy(&eh->ether_type, &etype, sizeof(eh->ether_type)); 192 memcpy(eh->ether_dhost, lladdr, ETHER_ADDR_LEN); 193 memcpy(eh->ether_shost, IF_LLADDR(ifp), ETHER_ADDR_LEN); 194 req->bufsize = sizeof(struct ether_header); 195 196 return (0); 197 } 198 199 static int 200 ether_resolve_addr(struct ifnet *ifp, struct mbuf *m, 201 const struct sockaddr *dst, struct route *ro, u_char *phdr, 202 uint32_t *pflags, struct llentry **plle) 203 { 204 uint32_t lleflags = 0; 205 int error = 0; 206 #if defined(INET) || defined(INET6) 207 struct ether_header *eh = (struct ether_header *)phdr; 208 uint16_t etype; 209 #endif 210 211 if (plle) 212 *plle = NULL; 213 214 switch (dst->sa_family) { 215 #ifdef INET 216 case AF_INET: 217 if ((m->m_flags & (M_BCAST | M_MCAST)) == 0) 218 error = arpresolve(ifp, 0, m, dst, phdr, &lleflags, 219 plle); 220 else { 221 if (m->m_flags & M_BCAST) 222 memcpy(eh->ether_dhost, ifp->if_broadcastaddr, 223 ETHER_ADDR_LEN); 224 else { 225 const struct in_addr *a; 226 a = &(((const struct sockaddr_in *)dst)->sin_addr); 227 ETHER_MAP_IP_MULTICAST(a, eh->ether_dhost); 228 } 229 etype = htons(ETHERTYPE_IP); 230 memcpy(&eh->ether_type, &etype, sizeof(etype)); 231 memcpy(eh->ether_shost, IF_LLADDR(ifp), ETHER_ADDR_LEN); 232 } 233 break; 234 #endif 235 #ifdef INET6 236 case AF_INET6: 237 if ((m->m_flags & M_MCAST) == 0) { 238 int af = RO_GET_FAMILY(ro, dst); 239 error = nd6_resolve(ifp, LLE_SF(af, 0), m, dst, phdr, 240 &lleflags, plle); 241 } else { 242 const struct in6_addr *a6; 243 a6 = &(((const struct sockaddr_in6 *)dst)->sin6_addr); 244 ETHER_MAP_IPV6_MULTICAST(a6, eh->ether_dhost); 245 etype = htons(ETHERTYPE_IPV6); 246 memcpy(&eh->ether_type, &etype, sizeof(etype)); 247 memcpy(eh->ether_shost, IF_LLADDR(ifp), ETHER_ADDR_LEN); 248 } 249 break; 250 #endif 251 default: 252 if_printf(ifp, "can't handle af%d\n", dst->sa_family); 253 if (m != NULL) 254 m_freem(m); 255 return (EAFNOSUPPORT); 256 } 257 258 if (error == EHOSTDOWN) { 259 if (ro != NULL && (ro->ro_flags & RT_HAS_GW) != 0) 260 error = EHOSTUNREACH; 261 } 262 263 if (error != 0) 264 return (error); 265 266 *pflags = RT_MAY_LOOP; 267 if (lleflags & LLE_IFADDR) 268 *pflags |= RT_L2_ME; 269 270 return (0); 271 } 272 273 /* 274 * Ethernet output routine. 275 * Encapsulate a packet of type family for the local net. 276 * Use trailer local net encapsulation if enough data in first 277 * packet leaves a multiple of 512 bytes of data in remainder. 278 */ 279 int 280 ether_output(struct ifnet *ifp, struct mbuf *m, 281 const struct sockaddr *dst, struct route *ro) 282 { 283 int error = 0; 284 char linkhdr[ETHER_HDR_LEN], *phdr; 285 struct ether_header *eh; 286 struct pf_mtag *t; 287 bool loop_copy; 288 int hlen; /* link layer header length */ 289 uint32_t pflags; 290 struct llentry *lle = NULL; 291 int addref = 0; 292 293 phdr = NULL; 294 pflags = 0; 295 if (ro != NULL) { 296 /* XXX BPF uses ro_prepend */ 297 if (ro->ro_prepend != NULL) { 298 phdr = ro->ro_prepend; 299 hlen = ro->ro_plen; 300 } else if (!(m->m_flags & (M_BCAST | M_MCAST))) { 301 if ((ro->ro_flags & RT_LLE_CACHE) != 0) { 302 lle = ro->ro_lle; 303 if (lle != NULL && 304 (lle->la_flags & LLE_VALID) == 0) { 305 LLE_FREE(lle); 306 lle = NULL; /* redundant */ 307 ro->ro_lle = NULL; 308 } 309 if (lle == NULL) { 310 /* if we lookup, keep cache */ 311 addref = 1; 312 } else 313 /* 314 * Notify LLE code that 315 * the entry was used 316 * by datapath. 317 */ 318 llentry_provide_feedback(lle); 319 } 320 if (lle != NULL) { 321 phdr = lle->r_linkdata; 322 hlen = lle->r_hdrlen; 323 pflags = lle->r_flags; 324 } 325 } 326 } 327 328 #ifdef MAC 329 error = mac_ifnet_check_transmit(ifp, m); 330 if (error) 331 senderr(error); 332 #endif 333 334 M_PROFILE(m); 335 if (ifp->if_flags & IFF_MONITOR) 336 senderr(ENETDOWN); 337 if (!((ifp->if_flags & IFF_UP) && 338 (ifp->if_drv_flags & IFF_DRV_RUNNING))) 339 senderr(ENETDOWN); 340 341 if (phdr == NULL) { 342 /* No prepend data supplied. Try to calculate ourselves. */ 343 phdr = linkhdr; 344 hlen = ETHER_HDR_LEN; 345 error = ether_resolve_addr(ifp, m, dst, ro, phdr, &pflags, 346 addref ? &lle : NULL); 347 if (addref && lle != NULL) 348 ro->ro_lle = lle; 349 if (error != 0) 350 return (error == EWOULDBLOCK ? 0 : error); 351 } 352 353 if ((pflags & RT_L2_ME) != 0) { 354 update_mbuf_csumflags(m, m); 355 return (if_simloop(ifp, m, RO_GET_FAMILY(ro, dst), 0)); 356 } 357 loop_copy = (pflags & RT_MAY_LOOP) != 0; 358 359 /* 360 * Add local net header. If no space in first mbuf, 361 * allocate another. 362 * 363 * Note that we do prepend regardless of RT_HAS_HEADER flag. 364 * This is done because BPF code shifts m_data pointer 365 * to the end of ethernet header prior to calling if_output(). 366 */ 367 M_PREPEND(m, hlen, M_NOWAIT); 368 if (m == NULL) 369 senderr(ENOBUFS); 370 if ((pflags & RT_HAS_HEADER) == 0) { 371 eh = mtod(m, struct ether_header *); 372 memcpy(eh, phdr, hlen); 373 } 374 375 /* 376 * If a simplex interface, and the packet is being sent to our 377 * Ethernet address or a broadcast address, loopback a copy. 378 * XXX To make a simplex device behave exactly like a duplex 379 * device, we should copy in the case of sending to our own 380 * ethernet address (thus letting the original actually appear 381 * on the wire). However, we don't do that here for security 382 * reasons and compatibility with the original behavior. 383 */ 384 if ((m->m_flags & M_BCAST) && loop_copy && (ifp->if_flags & IFF_SIMPLEX) && 385 ((t = pf_find_mtag(m)) == NULL || !t->routed)) { 386 struct mbuf *n; 387 388 /* 389 * Because if_simloop() modifies the packet, we need a 390 * writable copy through m_dup() instead of a readonly 391 * one as m_copy[m] would give us. The alternative would 392 * be to modify if_simloop() to handle the readonly mbuf, 393 * but performancewise it is mostly equivalent (trading 394 * extra data copying vs. extra locking). 395 * 396 * XXX This is a local workaround. A number of less 397 * often used kernel parts suffer from the same bug. 398 * See PR kern/105943 for a proposed general solution. 399 */ 400 if ((n = m_dup(m, M_NOWAIT)) != NULL) { 401 update_mbuf_csumflags(m, n); 402 (void)if_simloop(ifp, n, RO_GET_FAMILY(ro, dst), hlen); 403 } else 404 if_inc_counter(ifp, IFCOUNTER_IQDROPS, 1); 405 } 406 407 /* 408 * Bridges require special output handling. 409 */ 410 if (ifp->if_bridge) { 411 BRIDGE_OUTPUT(ifp, m, error); 412 return (error); 413 } 414 415 #if defined(INET) || defined(INET6) 416 if (ifp->if_carp && 417 (error = (*carp_output_p)(ifp, m, dst))) 418 goto bad; 419 #endif 420 421 /* Handle ng_ether(4) processing, if any */ 422 if (ifp->if_l2com != NULL) { 423 KASSERT(ng_ether_output_p != NULL, 424 ("ng_ether_output_p is NULL")); 425 if ((error = (*ng_ether_output_p)(ifp, &m)) != 0) { 426 bad: if (m != NULL) 427 m_freem(m); 428 return (error); 429 } 430 if (m == NULL) 431 return (0); 432 } 433 434 /* Continue with link-layer output */ 435 return ether_output_frame(ifp, m); 436 } 437 438 static bool 439 ether_set_pcp(struct mbuf **mp, struct ifnet *ifp, uint8_t pcp) 440 { 441 struct ether_8021q_tag qtag; 442 struct ether_header *eh; 443 444 eh = mtod(*mp, struct ether_header *); 445 if (eh->ether_type == htons(ETHERTYPE_VLAN) || 446 eh->ether_type == htons(ETHERTYPE_QINQ)) { 447 (*mp)->m_flags &= ~M_VLANTAG; 448 return (true); 449 } 450 451 qtag.vid = 0; 452 qtag.pcp = pcp; 453 qtag.proto = ETHERTYPE_VLAN; 454 if (ether_8021q_frame(mp, ifp, ifp, &qtag)) 455 return (true); 456 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 457 return (false); 458 } 459 460 /* 461 * Ethernet link layer output routine to send a raw frame to the device. 462 * 463 * This assumes that the 14 byte Ethernet header is present and contiguous 464 * in the first mbuf (if BRIDGE'ing). 465 */ 466 int 467 ether_output_frame(struct ifnet *ifp, struct mbuf *m) 468 { 469 if (ether_do_pcp(ifp, m) && !ether_set_pcp(&m, ifp, ifp->if_pcp)) 470 return (0); 471 472 if (PFIL_HOOKED_OUT(V_link_pfil_head)) 473 switch (pfil_mbuf_out(V_link_pfil_head, &m, ifp, NULL)) { 474 case PFIL_DROPPED: 475 return (EACCES); 476 case PFIL_CONSUMED: 477 return (0); 478 } 479 480 #ifdef EXPERIMENTAL 481 #if defined(INET6) && defined(INET) 482 /* draft-ietf-6man-ipv6only-flag */ 483 /* Catch ETHERTYPE_IP, and ETHERTYPE_[REV]ARP if we are v6-only. */ 484 if ((ND_IFINFO(ifp)->flags & ND6_IFF_IPV6_ONLY_MASK) != 0) { 485 struct ether_header *eh; 486 487 eh = mtod(m, struct ether_header *); 488 switch (ntohs(eh->ether_type)) { 489 case ETHERTYPE_IP: 490 case ETHERTYPE_ARP: 491 case ETHERTYPE_REVARP: 492 m_freem(m); 493 return (EAFNOSUPPORT); 494 /* NOTREACHED */ 495 break; 496 }; 497 } 498 #endif 499 #endif 500 501 /* 502 * Queue message on interface, update output statistics if successful, 503 * and start output if interface not yet active. 504 * 505 * If KMSAN is enabled, use it to verify that the data does not contain 506 * any uninitialized bytes. 507 */ 508 kmsan_check_mbuf(m, "ether_output"); 509 return ((ifp->if_transmit)(ifp, m)); 510 } 511 512 /* 513 * Process a received Ethernet packet; the packet is in the 514 * mbuf chain m with the ethernet header at the front. 515 */ 516 static void 517 ether_input_internal(struct ifnet *ifp, struct mbuf *m) 518 { 519 struct ether_header *eh; 520 u_short etype; 521 522 if ((ifp->if_flags & IFF_UP) == 0) { 523 m_freem(m); 524 return; 525 } 526 #ifdef DIAGNOSTIC 527 if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0) { 528 if_printf(ifp, "discard frame at !IFF_DRV_RUNNING\n"); 529 m_freem(m); 530 return; 531 } 532 #endif 533 if (__predict_false(m->m_len < ETHER_HDR_LEN)) { 534 /* Drivers should pullup and ensure the mbuf is valid */ 535 if_printf(ifp, "discard frame w/o leading ethernet " 536 "header (len %d pkt len %d)\n", 537 m->m_len, m->m_pkthdr.len); 538 if_inc_counter(ifp, IFCOUNTER_IERRORS, 1); 539 m_freem(m); 540 return; 541 } 542 eh = mtod(m, struct ether_header *); 543 etype = ntohs(eh->ether_type); 544 random_harvest_queue_ether(m, sizeof(*m)); 545 546 #ifdef EXPERIMENTAL 547 #if defined(INET6) && defined(INET) 548 /* draft-ietf-6man-ipv6only-flag */ 549 /* Catch ETHERTYPE_IP, and ETHERTYPE_[REV]ARP if we are v6-only. */ 550 if ((ND_IFINFO(ifp)->flags & ND6_IFF_IPV6_ONLY_MASK) != 0) { 551 switch (etype) { 552 case ETHERTYPE_IP: 553 case ETHERTYPE_ARP: 554 case ETHERTYPE_REVARP: 555 m_freem(m); 556 return; 557 /* NOTREACHED */ 558 break; 559 }; 560 } 561 #endif 562 #endif 563 564 CURVNET_SET_QUIET(ifp->if_vnet); 565 566 if (ETHER_IS_MULTICAST(eh->ether_dhost)) { 567 if (ETHER_IS_BROADCAST(eh->ether_dhost)) 568 m->m_flags |= M_BCAST; 569 else 570 m->m_flags |= M_MCAST; 571 if_inc_counter(ifp, IFCOUNTER_IMCASTS, 1); 572 } 573 574 #ifdef MAC 575 /* 576 * Tag the mbuf with an appropriate MAC label before any other 577 * consumers can get to it. 578 */ 579 mac_ifnet_create_mbuf(ifp, m); 580 #endif 581 582 /* 583 * Give bpf a chance at the packet. 584 */ 585 ETHER_BPF_MTAP(ifp, m); 586 587 if (!(ifp->if_capenable & IFCAP_HWSTATS)) 588 if_inc_counter(ifp, IFCOUNTER_IBYTES, m->m_pkthdr.len); 589 590 /* Allow monitor mode to claim this frame, after stats are updated. */ 591 if (ifp->if_flags & IFF_MONITOR) { 592 m_freem(m); 593 CURVNET_RESTORE(); 594 return; 595 } 596 597 /* Handle input from a lagg(4) port */ 598 if (ifp->if_type == IFT_IEEE8023ADLAG) { 599 KASSERT(lagg_input_ethernet_p != NULL, 600 ("%s: if_lagg not loaded!", __func__)); 601 m = (*lagg_input_ethernet_p)(ifp, m); 602 if (m != NULL) 603 ifp = m->m_pkthdr.rcvif; 604 else { 605 CURVNET_RESTORE(); 606 return; 607 } 608 } 609 610 /* 611 * If the hardware did not process an 802.1Q tag, do this now, 612 * to allow 802.1P priority frames to be passed to the main input 613 * path correctly. 614 */ 615 if ((m->m_flags & M_VLANTAG) == 0 && 616 ((etype == ETHERTYPE_VLAN) || (etype == ETHERTYPE_QINQ))) { 617 struct ether_vlan_header *evl; 618 619 if (m->m_len < sizeof(*evl) && 620 (m = m_pullup(m, sizeof(*evl))) == NULL) { 621 #ifdef DIAGNOSTIC 622 if_printf(ifp, "cannot pullup VLAN header\n"); 623 #endif 624 if_inc_counter(ifp, IFCOUNTER_IERRORS, 1); 625 CURVNET_RESTORE(); 626 return; 627 } 628 629 evl = mtod(m, struct ether_vlan_header *); 630 m->m_pkthdr.ether_vtag = ntohs(evl->evl_tag); 631 m->m_flags |= M_VLANTAG; 632 633 bcopy((char *)evl, (char *)evl + ETHER_VLAN_ENCAP_LEN, 634 ETHER_HDR_LEN - ETHER_TYPE_LEN); 635 m_adj(m, ETHER_VLAN_ENCAP_LEN); 636 eh = mtod(m, struct ether_header *); 637 } 638 639 M_SETFIB(m, ifp->if_fib); 640 641 /* Allow ng_ether(4) to claim this frame. */ 642 if (ifp->if_l2com != NULL) { 643 KASSERT(ng_ether_input_p != NULL, 644 ("%s: ng_ether_input_p is NULL", __func__)); 645 m->m_flags &= ~M_PROMISC; 646 (*ng_ether_input_p)(ifp, &m); 647 if (m == NULL) { 648 CURVNET_RESTORE(); 649 return; 650 } 651 eh = mtod(m, struct ether_header *); 652 } 653 654 /* 655 * Allow if_bridge(4) to claim this frame. 656 * 657 * The BRIDGE_INPUT() macro will update ifp if the bridge changed it 658 * and the frame should be delivered locally. 659 * 660 * If M_BRIDGE_INJECT is set, the packet was received directly by the 661 * bridge via netmap, so "ifp" is the bridge itself and the packet 662 * should be re-examined. 663 */ 664 if (ifp->if_bridge != NULL || (m->m_flags & M_BRIDGE_INJECT) != 0) { 665 m->m_flags &= ~M_PROMISC; 666 BRIDGE_INPUT(ifp, m); 667 if (m == NULL) { 668 CURVNET_RESTORE(); 669 return; 670 } 671 eh = mtod(m, struct ether_header *); 672 } 673 674 #if defined(INET) || defined(INET6) 675 /* 676 * Clear M_PROMISC on frame so that carp(4) will see it when the 677 * mbuf flows up to Layer 3. 678 * FreeBSD's implementation of carp(4) uses the inprotosw 679 * to dispatch IPPROTO_CARP. carp(4) also allocates its own 680 * Ethernet addresses of the form 00:00:5e:00:01:xx, which 681 * is outside the scope of the M_PROMISC test below. 682 * TODO: Maintain a hash table of ethernet addresses other than 683 * ether_dhost which may be active on this ifp. 684 */ 685 if (ifp->if_carp && (*carp_forus_p)(ifp, eh->ether_dhost)) { 686 m->m_flags &= ~M_PROMISC; 687 } else 688 #endif 689 { 690 /* 691 * If the frame received was not for our MAC address, set the 692 * M_PROMISC flag on the mbuf chain. The frame may need to 693 * be seen by the rest of the Ethernet input path in case of 694 * re-entry (e.g. bridge, vlan, netgraph) but should not be 695 * seen by upper protocol layers. 696 */ 697 if (!ETHER_IS_MULTICAST(eh->ether_dhost) && 698 bcmp(IF_LLADDR(ifp), eh->ether_dhost, ETHER_ADDR_LEN) != 0) 699 m->m_flags |= M_PROMISC; 700 } 701 702 ether_demux(ifp, m); 703 CURVNET_RESTORE(); 704 } 705 706 /* 707 * Ethernet input dispatch; by default, direct dispatch here regardless of 708 * global configuration. However, if RSS is enabled, hook up RSS affinity 709 * so that when deferred or hybrid dispatch is enabled, we can redistribute 710 * load based on RSS. 711 * 712 * XXXRW: Would be nice if the ifnet passed up a flag indicating whether or 713 * not it had already done work distribution via multi-queue. Then we could 714 * direct dispatch in the event load balancing was already complete and 715 * handle the case of interfaces with different capabilities better. 716 * 717 * XXXRW: Sort of want an M_DISTRIBUTED flag to avoid multiple distributions 718 * at multiple layers? 719 * 720 * XXXRW: For now, enable all this only if RSS is compiled in, although it 721 * works fine without RSS. Need to characterise the performance overhead 722 * of the detour through the netisr code in the event the result is always 723 * direct dispatch. 724 */ 725 static void 726 ether_nh_input(struct mbuf *m) 727 { 728 729 M_ASSERTPKTHDR(m); 730 KASSERT(m->m_pkthdr.rcvif != NULL, 731 ("%s: NULL interface pointer", __func__)); 732 ether_input_internal(m->m_pkthdr.rcvif, m); 733 } 734 735 static struct netisr_handler ether_nh = { 736 .nh_name = "ether", 737 .nh_handler = ether_nh_input, 738 .nh_proto = NETISR_ETHER, 739 #ifdef RSS 740 .nh_policy = NETISR_POLICY_CPU, 741 .nh_dispatch = NETISR_DISPATCH_DIRECT, 742 .nh_m2cpuid = rss_m2cpuid, 743 #else 744 .nh_policy = NETISR_POLICY_SOURCE, 745 .nh_dispatch = NETISR_DISPATCH_DIRECT, 746 #endif 747 }; 748 749 static void 750 ether_init(__unused void *arg) 751 { 752 753 netisr_register(ðer_nh); 754 } 755 SYSINIT(ether, SI_SUB_INIT_IF, SI_ORDER_ANY, ether_init, NULL); 756 757 static void 758 vnet_ether_init(const __unused void *arg) 759 { 760 struct pfil_head_args args; 761 762 args.pa_version = PFIL_VERSION; 763 args.pa_flags = PFIL_IN | PFIL_OUT; 764 args.pa_type = PFIL_TYPE_ETHERNET; 765 args.pa_headname = PFIL_ETHER_NAME; 766 V_link_pfil_head = pfil_head_register(&args); 767 768 #ifdef VIMAGE 769 netisr_register_vnet(ðer_nh); 770 #endif 771 } 772 VNET_SYSINIT(vnet_ether_init, SI_SUB_PROTO_IF, SI_ORDER_ANY, 773 vnet_ether_init, NULL); 774 775 #ifdef VIMAGE 776 static void 777 vnet_ether_pfil_destroy(const __unused void *arg) 778 { 779 780 pfil_head_unregister(V_link_pfil_head); 781 } 782 VNET_SYSUNINIT(vnet_ether_pfil_uninit, SI_SUB_PROTO_PFIL, SI_ORDER_ANY, 783 vnet_ether_pfil_destroy, NULL); 784 785 static void 786 vnet_ether_destroy(__unused void *arg) 787 { 788 789 netisr_unregister_vnet(ðer_nh); 790 } 791 VNET_SYSUNINIT(vnet_ether_uninit, SI_SUB_PROTO_IF, SI_ORDER_ANY, 792 vnet_ether_destroy, NULL); 793 #endif 794 795 static void 796 ether_input(struct ifnet *ifp, struct mbuf *m) 797 { 798 struct epoch_tracker et; 799 struct mbuf *mn; 800 bool needs_epoch; 801 802 needs_epoch = (ifp->if_flags & IFF_NEEDSEPOCH); 803 #ifdef INVARIANTS 804 /* 805 * This temporary code is here to prevent epoch unaware and unmarked 806 * drivers to panic the system. Once all drivers are taken care of, 807 * the whole INVARIANTS block should go away. 808 */ 809 if (!needs_epoch && !in_epoch(net_epoch_preempt)) { 810 static bool printedonce; 811 812 needs_epoch = true; 813 if (!printedonce) { 814 printedonce = true; 815 if_printf(ifp, "called %s w/o net epoch! " 816 "PLEASE file a bug report.", __func__); 817 #ifdef KDB 818 kdb_backtrace(); 819 #endif 820 } 821 } 822 #endif 823 824 /* 825 * The drivers are allowed to pass in a chain of packets linked with 826 * m_nextpkt. We split them up into separate packets here and pass 827 * them up. This allows the drivers to amortize the receive lock. 828 */ 829 CURVNET_SET_QUIET(ifp->if_vnet); 830 if (__predict_false(needs_epoch)) 831 NET_EPOCH_ENTER(et); 832 while (m) { 833 mn = m->m_nextpkt; 834 m->m_nextpkt = NULL; 835 836 /* 837 * We will rely on rcvif being set properly in the deferred 838 * context, so assert it is correct here. 839 */ 840 MPASS((m->m_pkthdr.csum_flags & CSUM_SND_TAG) == 0); 841 KASSERT(m->m_pkthdr.rcvif == ifp, ("%s: ifnet mismatch m %p " 842 "rcvif %p ifp %p", __func__, m, m->m_pkthdr.rcvif, ifp)); 843 netisr_dispatch(NETISR_ETHER, m); 844 m = mn; 845 } 846 if (__predict_false(needs_epoch)) 847 NET_EPOCH_EXIT(et); 848 CURVNET_RESTORE(); 849 } 850 851 /* 852 * Upper layer processing for a received Ethernet packet. 853 */ 854 void 855 ether_demux(struct ifnet *ifp, struct mbuf *m) 856 { 857 struct ether_header *eh; 858 int i, isr; 859 u_short ether_type; 860 861 NET_EPOCH_ASSERT(); 862 KASSERT(ifp != NULL, ("%s: NULL interface pointer", __func__)); 863 864 /* Do not grab PROMISC frames in case we are re-entered. */ 865 if (PFIL_HOOKED_IN(V_link_pfil_head) && !(m->m_flags & M_PROMISC)) { 866 i = pfil_mbuf_in(V_link_pfil_head, &m, ifp, NULL); 867 if (i != PFIL_PASS) 868 return; 869 } 870 871 eh = mtod(m, struct ether_header *); 872 ether_type = ntohs(eh->ether_type); 873 874 /* 875 * If this frame has a VLAN tag other than 0, call vlan_input() 876 * if its module is loaded. Otherwise, drop. 877 */ 878 if ((m->m_flags & M_VLANTAG) && 879 EVL_VLANOFTAG(m->m_pkthdr.ether_vtag) != 0) { 880 if (ifp->if_vlantrunk == NULL) { 881 if_inc_counter(ifp, IFCOUNTER_NOPROTO, 1); 882 m_freem(m); 883 return; 884 } 885 KASSERT(vlan_input_p != NULL,("%s: VLAN not loaded!", 886 __func__)); 887 /* Clear before possibly re-entering ether_input(). */ 888 m->m_flags &= ~M_PROMISC; 889 (*vlan_input_p)(ifp, m); 890 return; 891 } 892 893 /* 894 * Pass promiscuously received frames to the upper layer if the user 895 * requested this by setting IFF_PPROMISC. Otherwise, drop them. 896 */ 897 if ((ifp->if_flags & IFF_PPROMISC) == 0 && (m->m_flags & M_PROMISC)) { 898 m_freem(m); 899 return; 900 } 901 902 /* 903 * Reset layer specific mbuf flags to avoid confusing upper layers. 904 */ 905 m->m_flags &= ~M_VLANTAG; 906 m_clrprotoflags(m); 907 908 /* 909 * Dispatch frame to upper layer. 910 */ 911 switch (ether_type) { 912 #ifdef INET 913 case ETHERTYPE_IP: 914 isr = NETISR_IP; 915 break; 916 917 case ETHERTYPE_ARP: 918 if (ifp->if_flags & IFF_NOARP) { 919 /* Discard packet if ARP is disabled on interface */ 920 m_freem(m); 921 return; 922 } 923 isr = NETISR_ARP; 924 break; 925 #endif 926 #ifdef INET6 927 case ETHERTYPE_IPV6: 928 isr = NETISR_IPV6; 929 break; 930 #endif 931 default: 932 goto discard; 933 } 934 935 /* Strip off Ethernet header. */ 936 m_adj(m, ETHER_HDR_LEN); 937 938 netisr_dispatch(isr, m); 939 return; 940 941 discard: 942 /* 943 * Packet is to be discarded. If netgraph is present, 944 * hand the packet to it for last chance processing; 945 * otherwise dispose of it. 946 */ 947 if (ifp->if_l2com != NULL) { 948 KASSERT(ng_ether_input_orphan_p != NULL, 949 ("ng_ether_input_orphan_p is NULL")); 950 (*ng_ether_input_orphan_p)(ifp, m); 951 return; 952 } 953 m_freem(m); 954 } 955 956 /* 957 * Convert Ethernet address to printable (loggable) representation. 958 * This routine is for compatibility; it's better to just use 959 * 960 * printf("%6D", <pointer to address>, ":"); 961 * 962 * since there's no static buffer involved. 963 */ 964 char * 965 ether_sprintf(const u_char *ap) 966 { 967 static char etherbuf[18]; 968 snprintf(etherbuf, sizeof (etherbuf), "%6D", ap, ":"); 969 return (etherbuf); 970 } 971 972 /* 973 * Perform common duties while attaching to interface list 974 */ 975 void 976 ether_ifattach(struct ifnet *ifp, const u_int8_t *lla) 977 { 978 int i; 979 struct ifaddr *ifa; 980 struct sockaddr_dl *sdl; 981 982 ifp->if_addrlen = ETHER_ADDR_LEN; 983 ifp->if_hdrlen = (ifp->if_capabilities & IFCAP_VLAN_MTU) != 0 ? 984 ETHER_HDR_LEN + ETHER_VLAN_ENCAP_LEN : ETHER_HDR_LEN; 985 ifp->if_mtu = ETHERMTU; 986 if_attach(ifp); 987 ifp->if_output = ether_output; 988 ifp->if_input = ether_input; 989 ifp->if_resolvemulti = ether_resolvemulti; 990 ifp->if_requestencap = ether_requestencap; 991 #ifdef VIMAGE 992 ifp->if_reassign = ether_reassign; 993 #endif 994 if (ifp->if_baudrate == 0) 995 ifp->if_baudrate = IF_Mbps(10); /* just a default */ 996 ifp->if_broadcastaddr = etherbroadcastaddr; 997 998 ifa = ifp->if_addr; 999 KASSERT(ifa != NULL, ("%s: no lladdr!\n", __func__)); 1000 sdl = (struct sockaddr_dl *)ifa->ifa_addr; 1001 sdl->sdl_type = IFT_ETHER; 1002 sdl->sdl_alen = ifp->if_addrlen; 1003 bcopy(lla, LLADDR(sdl), ifp->if_addrlen); 1004 1005 if (ifp->if_hw_addr != NULL) 1006 bcopy(lla, ifp->if_hw_addr, ifp->if_addrlen); 1007 1008 bpfattach(ifp, DLT_EN10MB, ETHER_HDR_LEN); 1009 if (ng_ether_attach_p != NULL) 1010 (*ng_ether_attach_p)(ifp); 1011 1012 /* Announce Ethernet MAC address if non-zero. */ 1013 for (i = 0; i < ifp->if_addrlen; i++) 1014 if (lla[i] != 0) 1015 break; 1016 if (i != ifp->if_addrlen) 1017 if_printf(ifp, "Ethernet address: %6D\n", lla, ":"); 1018 1019 uuid_ether_add(LLADDR(sdl)); 1020 1021 /* Add necessary bits are setup; announce it now. */ 1022 EVENTHANDLER_INVOKE(ether_ifattach_event, ifp); 1023 if (IS_DEFAULT_VNET(curvnet)) 1024 devctl_notify("ETHERNET", ifp->if_xname, "IFATTACH", NULL); 1025 } 1026 1027 /* 1028 * Perform common duties while detaching an Ethernet interface 1029 */ 1030 void 1031 ether_ifdetach(struct ifnet *ifp) 1032 { 1033 struct sockaddr_dl *sdl; 1034 1035 sdl = (struct sockaddr_dl *)(ifp->if_addr->ifa_addr); 1036 uuid_ether_del(LLADDR(sdl)); 1037 1038 if (ifp->if_l2com != NULL) { 1039 KASSERT(ng_ether_detach_p != NULL, 1040 ("ng_ether_detach_p is NULL")); 1041 (*ng_ether_detach_p)(ifp); 1042 } 1043 1044 bpfdetach(ifp); 1045 if_detach(ifp); 1046 } 1047 1048 #ifdef VIMAGE 1049 void 1050 ether_reassign(struct ifnet *ifp, struct vnet *new_vnet, char *unused __unused) 1051 { 1052 1053 if (ifp->if_l2com != NULL) { 1054 KASSERT(ng_ether_detach_p != NULL, 1055 ("ng_ether_detach_p is NULL")); 1056 (*ng_ether_detach_p)(ifp); 1057 } 1058 1059 if (ng_ether_attach_p != NULL) { 1060 CURVNET_SET_QUIET(new_vnet); 1061 (*ng_ether_attach_p)(ifp); 1062 CURVNET_RESTORE(); 1063 } 1064 } 1065 #endif 1066 1067 SYSCTL_DECL(_net_link); 1068 SYSCTL_NODE(_net_link, IFT_ETHER, ether, CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 1069 "Ethernet"); 1070 1071 #if 0 1072 /* 1073 * This is for reference. We have a table-driven version 1074 * of the little-endian crc32 generator, which is faster 1075 * than the double-loop. 1076 */ 1077 uint32_t 1078 ether_crc32_le(const uint8_t *buf, size_t len) 1079 { 1080 size_t i; 1081 uint32_t crc; 1082 int bit; 1083 uint8_t data; 1084 1085 crc = 0xffffffff; /* initial value */ 1086 1087 for (i = 0; i < len; i++) { 1088 for (data = *buf++, bit = 0; bit < 8; bit++, data >>= 1) { 1089 carry = (crc ^ data) & 1; 1090 crc >>= 1; 1091 if (carry) 1092 crc = (crc ^ ETHER_CRC_POLY_LE); 1093 } 1094 } 1095 1096 return (crc); 1097 } 1098 #else 1099 uint32_t 1100 ether_crc32_le(const uint8_t *buf, size_t len) 1101 { 1102 static const uint32_t crctab[] = { 1103 0x00000000, 0x1db71064, 0x3b6e20c8, 0x26d930ac, 1104 0x76dc4190, 0x6b6b51f4, 0x4db26158, 0x5005713c, 1105 0xedb88320, 0xf00f9344, 0xd6d6a3e8, 0xcb61b38c, 1106 0x9b64c2b0, 0x86d3d2d4, 0xa00ae278, 0xbdbdf21c 1107 }; 1108 size_t i; 1109 uint32_t crc; 1110 1111 crc = 0xffffffff; /* initial value */ 1112 1113 for (i = 0; i < len; i++) { 1114 crc ^= buf[i]; 1115 crc = (crc >> 4) ^ crctab[crc & 0xf]; 1116 crc = (crc >> 4) ^ crctab[crc & 0xf]; 1117 } 1118 1119 return (crc); 1120 } 1121 #endif 1122 1123 uint32_t 1124 ether_crc32_be(const uint8_t *buf, size_t len) 1125 { 1126 size_t i; 1127 uint32_t crc, carry; 1128 int bit; 1129 uint8_t data; 1130 1131 crc = 0xffffffff; /* initial value */ 1132 1133 for (i = 0; i < len; i++) { 1134 for (data = *buf++, bit = 0; bit < 8; bit++, data >>= 1) { 1135 carry = ((crc & 0x80000000) ? 1 : 0) ^ (data & 0x01); 1136 crc <<= 1; 1137 if (carry) 1138 crc = (crc ^ ETHER_CRC_POLY_BE) | carry; 1139 } 1140 } 1141 1142 return (crc); 1143 } 1144 1145 int 1146 ether_ioctl(struct ifnet *ifp, u_long command, caddr_t data) 1147 { 1148 struct ifaddr *ifa = (struct ifaddr *) data; 1149 struct ifreq *ifr = (struct ifreq *) data; 1150 int error = 0; 1151 1152 switch (command) { 1153 case SIOCSIFADDR: 1154 ifp->if_flags |= IFF_UP; 1155 1156 switch (ifa->ifa_addr->sa_family) { 1157 #ifdef INET 1158 case AF_INET: 1159 ifp->if_init(ifp->if_softc); /* before arpwhohas */ 1160 arp_ifinit(ifp, ifa); 1161 break; 1162 #endif 1163 default: 1164 ifp->if_init(ifp->if_softc); 1165 break; 1166 } 1167 break; 1168 1169 case SIOCGIFADDR: 1170 bcopy(IF_LLADDR(ifp), &ifr->ifr_addr.sa_data[0], 1171 ETHER_ADDR_LEN); 1172 break; 1173 1174 case SIOCSIFMTU: 1175 /* 1176 * Set the interface MTU. 1177 */ 1178 if (ifr->ifr_mtu > ETHERMTU) { 1179 error = EINVAL; 1180 } else { 1181 ifp->if_mtu = ifr->ifr_mtu; 1182 } 1183 break; 1184 1185 case SIOCSLANPCP: 1186 error = priv_check(curthread, PRIV_NET_SETLANPCP); 1187 if (error != 0) 1188 break; 1189 if (ifr->ifr_lan_pcp > 7 && 1190 ifr->ifr_lan_pcp != IFNET_PCP_NONE) { 1191 error = EINVAL; 1192 } else { 1193 ifp->if_pcp = ifr->ifr_lan_pcp; 1194 /* broadcast event about PCP change */ 1195 EVENTHANDLER_INVOKE(ifnet_event, ifp, IFNET_EVENT_PCP); 1196 } 1197 break; 1198 1199 case SIOCGLANPCP: 1200 ifr->ifr_lan_pcp = ifp->if_pcp; 1201 break; 1202 1203 default: 1204 error = EINVAL; /* XXX netbsd has ENOTTY??? */ 1205 break; 1206 } 1207 return (error); 1208 } 1209 1210 static int 1211 ether_resolvemulti(struct ifnet *ifp, struct sockaddr **llsa, 1212 struct sockaddr *sa) 1213 { 1214 struct sockaddr_dl *sdl; 1215 #ifdef INET 1216 struct sockaddr_in *sin; 1217 #endif 1218 #ifdef INET6 1219 struct sockaddr_in6 *sin6; 1220 #endif 1221 u_char *e_addr; 1222 1223 switch(sa->sa_family) { 1224 case AF_LINK: 1225 /* 1226 * No mapping needed. Just check that it's a valid MC address. 1227 */ 1228 sdl = (struct sockaddr_dl *)sa; 1229 e_addr = LLADDR(sdl); 1230 if (!ETHER_IS_MULTICAST(e_addr)) 1231 return EADDRNOTAVAIL; 1232 *llsa = NULL; 1233 return 0; 1234 1235 #ifdef INET 1236 case AF_INET: 1237 sin = (struct sockaddr_in *)sa; 1238 if (!IN_MULTICAST(ntohl(sin->sin_addr.s_addr))) 1239 return EADDRNOTAVAIL; 1240 sdl = link_init_sdl(ifp, *llsa, IFT_ETHER); 1241 sdl->sdl_alen = ETHER_ADDR_LEN; 1242 e_addr = LLADDR(sdl); 1243 ETHER_MAP_IP_MULTICAST(&sin->sin_addr, e_addr); 1244 *llsa = (struct sockaddr *)sdl; 1245 return 0; 1246 #endif 1247 #ifdef INET6 1248 case AF_INET6: 1249 sin6 = (struct sockaddr_in6 *)sa; 1250 if (IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr)) { 1251 /* 1252 * An IP6 address of 0 means listen to all 1253 * of the Ethernet multicast address used for IP6. 1254 * (This is used for multicast routers.) 1255 */ 1256 ifp->if_flags |= IFF_ALLMULTI; 1257 *llsa = NULL; 1258 return 0; 1259 } 1260 if (!IN6_IS_ADDR_MULTICAST(&sin6->sin6_addr)) 1261 return EADDRNOTAVAIL; 1262 sdl = link_init_sdl(ifp, *llsa, IFT_ETHER); 1263 sdl->sdl_alen = ETHER_ADDR_LEN; 1264 e_addr = LLADDR(sdl); 1265 ETHER_MAP_IPV6_MULTICAST(&sin6->sin6_addr, e_addr); 1266 *llsa = (struct sockaddr *)sdl; 1267 return 0; 1268 #endif 1269 1270 default: 1271 /* 1272 * Well, the text isn't quite right, but it's the name 1273 * that counts... 1274 */ 1275 return EAFNOSUPPORT; 1276 } 1277 } 1278 1279 static moduledata_t ether_mod = { 1280 .name = "ether", 1281 }; 1282 1283 void 1284 ether_vlan_mtap(struct bpf_if *bp, struct mbuf *m, void *data, u_int dlen) 1285 { 1286 struct ether_vlan_header vlan; 1287 struct mbuf mv, mb; 1288 1289 KASSERT((m->m_flags & M_VLANTAG) != 0, 1290 ("%s: vlan information not present", __func__)); 1291 KASSERT(m->m_len >= sizeof(struct ether_header), 1292 ("%s: mbuf not large enough for header", __func__)); 1293 bcopy(mtod(m, char *), &vlan, sizeof(struct ether_header)); 1294 vlan.evl_proto = vlan.evl_encap_proto; 1295 vlan.evl_encap_proto = htons(ETHERTYPE_VLAN); 1296 vlan.evl_tag = htons(m->m_pkthdr.ether_vtag); 1297 m->m_len -= sizeof(struct ether_header); 1298 m->m_data += sizeof(struct ether_header); 1299 /* 1300 * If a data link has been supplied by the caller, then we will need to 1301 * re-create a stack allocated mbuf chain with the following structure: 1302 * 1303 * (1) mbuf #1 will contain the supplied data link 1304 * (2) mbuf #2 will contain the vlan header 1305 * (3) mbuf #3 will contain the original mbuf's packet data 1306 * 1307 * Otherwise, submit the packet and vlan header via bpf_mtap2(). 1308 */ 1309 if (data != NULL) { 1310 mv.m_next = m; 1311 mv.m_data = (caddr_t)&vlan; 1312 mv.m_len = sizeof(vlan); 1313 mb.m_next = &mv; 1314 mb.m_data = data; 1315 mb.m_len = dlen; 1316 bpf_mtap(bp, &mb); 1317 } else 1318 bpf_mtap2(bp, &vlan, sizeof(vlan), m); 1319 m->m_len += sizeof(struct ether_header); 1320 m->m_data -= sizeof(struct ether_header); 1321 } 1322 1323 struct mbuf * 1324 ether_vlanencap_proto(struct mbuf *m, uint16_t tag, uint16_t proto) 1325 { 1326 struct ether_vlan_header *evl; 1327 1328 M_PREPEND(m, ETHER_VLAN_ENCAP_LEN, M_NOWAIT); 1329 if (m == NULL) 1330 return (NULL); 1331 /* M_PREPEND takes care of m_len, m_pkthdr.len for us */ 1332 1333 if (m->m_len < sizeof(*evl)) { 1334 m = m_pullup(m, sizeof(*evl)); 1335 if (m == NULL) 1336 return (NULL); 1337 } 1338 1339 /* 1340 * Transform the Ethernet header into an Ethernet header 1341 * with 802.1Q encapsulation. 1342 */ 1343 evl = mtod(m, struct ether_vlan_header *); 1344 bcopy((char *)evl + ETHER_VLAN_ENCAP_LEN, 1345 (char *)evl, ETHER_HDR_LEN - ETHER_TYPE_LEN); 1346 evl->evl_encap_proto = htons(proto); 1347 evl->evl_tag = htons(tag); 1348 return (m); 1349 } 1350 1351 void 1352 ether_bpf_mtap_if(struct ifnet *ifp, struct mbuf *m) 1353 { 1354 if (bpf_peers_present(ifp->if_bpf)) { 1355 M_ASSERTVALID(m); 1356 if ((m->m_flags & M_VLANTAG) != 0) 1357 ether_vlan_mtap(ifp->if_bpf, m, NULL, 0); 1358 else 1359 bpf_mtap(ifp->if_bpf, m); 1360 } 1361 } 1362 1363 static SYSCTL_NODE(_net_link, IFT_L2VLAN, vlan, CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 1364 "IEEE 802.1Q VLAN"); 1365 static SYSCTL_NODE(_net_link_vlan, PF_LINK, link, 1366 CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 1367 "for consistency"); 1368 1369 VNET_DEFINE_STATIC(int, soft_pad); 1370 #define V_soft_pad VNET(soft_pad) 1371 SYSCTL_INT(_net_link_vlan, OID_AUTO, soft_pad, CTLFLAG_RW | CTLFLAG_VNET, 1372 &VNET_NAME(soft_pad), 0, 1373 "pad short frames before tagging"); 1374 1375 /* 1376 * For now, make preserving PCP via an mbuf tag optional, as it increases 1377 * per-packet memory allocations and frees. In the future, it would be 1378 * preferable to reuse ether_vtag for this, or similar. 1379 */ 1380 VNET_DEFINE(int, vlan_mtag_pcp) = 0; 1381 #define V_vlan_mtag_pcp VNET(vlan_mtag_pcp) 1382 SYSCTL_INT(_net_link_vlan, OID_AUTO, mtag_pcp, CTLFLAG_RW | CTLFLAG_VNET, 1383 &VNET_NAME(vlan_mtag_pcp), 0, 1384 "Retain VLAN PCP information as packets are passed up the stack"); 1385 1386 static inline bool 1387 ether_do_pcp(struct ifnet *ifp, struct mbuf *m) 1388 { 1389 if (ifp->if_type == IFT_L2VLAN) 1390 return (false); 1391 if (ifp->if_pcp != IFNET_PCP_NONE || (m->m_flags & M_VLANTAG) != 0) 1392 return (true); 1393 if (V_vlan_mtag_pcp && 1394 m_tag_locate(m, MTAG_8021Q, MTAG_8021Q_PCP_OUT, NULL) != NULL) 1395 return (true); 1396 return (false); 1397 } 1398 1399 bool 1400 ether_8021q_frame(struct mbuf **mp, struct ifnet *ife, struct ifnet *p, 1401 const struct ether_8021q_tag *qtag) 1402 { 1403 struct m_tag *mtag; 1404 int n; 1405 uint16_t tag; 1406 uint8_t pcp = qtag->pcp; 1407 static const char pad[8]; /* just zeros */ 1408 1409 /* 1410 * Pad the frame to the minimum size allowed if told to. 1411 * This option is in accord with IEEE Std 802.1Q, 2003 Ed., 1412 * paragraph C.4.4.3.b. It can help to work around buggy 1413 * bridges that violate paragraph C.4.4.3.a from the same 1414 * document, i.e., fail to pad short frames after untagging. 1415 * E.g., a tagged frame 66 bytes long (incl. FCS) is OK, but 1416 * untagging it will produce a 62-byte frame, which is a runt 1417 * and requires padding. There are VLAN-enabled network 1418 * devices that just discard such runts instead or mishandle 1419 * them somehow. 1420 */ 1421 if (V_soft_pad && p->if_type == IFT_ETHER) { 1422 for (n = ETHERMIN + ETHER_HDR_LEN - (*mp)->m_pkthdr.len; 1423 n > 0; n -= sizeof(pad)) { 1424 if (!m_append(*mp, min(n, sizeof(pad)), pad)) 1425 break; 1426 } 1427 if (n > 0) { 1428 m_freem(*mp); 1429 *mp = NULL; 1430 if_printf(ife, "cannot pad short frame"); 1431 return (false); 1432 } 1433 } 1434 1435 /* 1436 * If PCP is set in mbuf, use it 1437 */ 1438 if ((*mp)->m_flags & M_VLANTAG) { 1439 pcp = EVL_PRIOFTAG((*mp)->m_pkthdr.ether_vtag); 1440 } 1441 1442 /* 1443 * If underlying interface can do VLAN tag insertion itself, 1444 * just pass the packet along. However, we need some way to 1445 * tell the interface where the packet came from so that it 1446 * knows how to find the VLAN tag to use, so we attach a 1447 * packet tag that holds it. 1448 */ 1449 if (V_vlan_mtag_pcp && (mtag = m_tag_locate(*mp, MTAG_8021Q, 1450 MTAG_8021Q_PCP_OUT, NULL)) != NULL) 1451 tag = EVL_MAKETAG(qtag->vid, *(uint8_t *)(mtag + 1), 0); 1452 else 1453 tag = EVL_MAKETAG(qtag->vid, pcp, 0); 1454 if ((p->if_capenable & IFCAP_VLAN_HWTAGGING) && 1455 (qtag->proto == ETHERTYPE_VLAN)) { 1456 (*mp)->m_pkthdr.ether_vtag = tag; 1457 (*mp)->m_flags |= M_VLANTAG; 1458 } else { 1459 *mp = ether_vlanencap_proto(*mp, tag, qtag->proto); 1460 if (*mp == NULL) { 1461 if_printf(ife, "unable to prepend 802.1Q header"); 1462 return (false); 1463 } 1464 (*mp)->m_flags &= ~M_VLANTAG; 1465 } 1466 return (true); 1467 } 1468 1469 /* 1470 * Allocate an address from the FreeBSD Foundation OUI. This uses a 1471 * cryptographic hash function on the containing jail's name, UUID and the 1472 * interface name to attempt to provide a unique but stable address. 1473 * Pseudo-interfaces which require a MAC address should use this function to 1474 * allocate non-locally-administered addresses. 1475 */ 1476 void 1477 ether_gen_addr_byname(const char *nameunit, struct ether_addr *hwaddr) 1478 { 1479 SHA1_CTX ctx; 1480 char *buf; 1481 char uuid[HOSTUUIDLEN + 1]; 1482 uint64_t addr; 1483 int i, sz; 1484 unsigned char digest[SHA1_RESULTLEN]; 1485 char jailname[MAXHOSTNAMELEN]; 1486 1487 getcredhostuuid(curthread->td_ucred, uuid, sizeof(uuid)); 1488 if (strncmp(uuid, DEFAULT_HOSTUUID, sizeof(uuid)) == 0) { 1489 /* Fall back to a random mac address. */ 1490 goto rando; 1491 } 1492 1493 /* If each (vnet) jail would also have a unique hostuuid this would not 1494 * be necessary. */ 1495 getjailname(curthread->td_ucred, jailname, sizeof(jailname)); 1496 sz = asprintf(&buf, M_TEMP, "%s-%s-%s", uuid, nameunit, 1497 jailname); 1498 if (sz < 0) { 1499 /* Fall back to a random mac address. */ 1500 goto rando; 1501 } 1502 1503 SHA1Init(&ctx); 1504 SHA1Update(&ctx, buf, sz); 1505 SHA1Final(digest, &ctx); 1506 free(buf, M_TEMP); 1507 1508 addr = (digest[0] << 8) | digest[1] | OUI_FREEBSD_GENERATED_LOW; 1509 for (i = 0; i < ETHER_ADDR_LEN; ++i) { 1510 hwaddr->octet[i] = addr >> ((ETHER_ADDR_LEN - i - 1) * 8) & 1511 0xFF; 1512 } 1513 1514 return; 1515 rando: 1516 arc4rand(hwaddr, sizeof(*hwaddr), 0); 1517 /* Unicast */ 1518 hwaddr->octet[0] &= 0xFE; 1519 /* Locally administered. */ 1520 hwaddr->octet[0] |= 0x02; 1521 } 1522 1523 void 1524 ether_gen_addr(struct ifnet *ifp, struct ether_addr *hwaddr) 1525 { 1526 ether_gen_addr_byname(if_name(ifp), hwaddr); 1527 } 1528 1529 DECLARE_MODULE(ether, ether_mod, SI_SUB_INIT_IF, SI_ORDER_ANY); 1530 MODULE_VERSION(ether, 1); 1531