1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1982, 1989, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 * 31 * @(#)if_ethersubr.c 8.1 (Berkeley) 6/10/93 32 * $FreeBSD$ 33 */ 34 35 #include "opt_inet.h" 36 #include "opt_inet6.h" 37 #include "opt_netgraph.h" 38 #include "opt_mbuf_profiling.h" 39 #include "opt_rss.h" 40 41 #include <sys/param.h> 42 #include <sys/systm.h> 43 #include <sys/devctl.h> 44 #include <sys/eventhandler.h> 45 #include <sys/jail.h> 46 #include <sys/kernel.h> 47 #include <sys/lock.h> 48 #include <sys/malloc.h> 49 #include <sys/module.h> 50 #include <sys/mbuf.h> 51 #include <sys/proc.h> 52 #include <sys/priv.h> 53 #include <sys/random.h> 54 #include <sys/socket.h> 55 #include <sys/sockio.h> 56 #include <sys/sysctl.h> 57 #include <sys/uuid.h> 58 59 #include <net/ieee_oui.h> 60 #include <net/if.h> 61 #include <net/if_var.h> 62 #include <net/if_arp.h> 63 #include <net/netisr.h> 64 #include <net/route.h> 65 #include <net/if_llc.h> 66 #include <net/if_dl.h> 67 #include <net/if_types.h> 68 #include <net/bpf.h> 69 #include <net/ethernet.h> 70 #include <net/if_bridgevar.h> 71 #include <net/if_vlan_var.h> 72 #include <net/if_llatbl.h> 73 #include <net/pfil.h> 74 #include <net/rss_config.h> 75 #include <net/vnet.h> 76 77 #include <netpfil/pf/pf_mtag.h> 78 79 #if defined(INET) || defined(INET6) 80 #include <netinet/in.h> 81 #include <netinet/in_var.h> 82 #include <netinet/if_ether.h> 83 #include <netinet/ip_carp.h> 84 #include <netinet/ip_var.h> 85 #endif 86 #ifdef INET6 87 #include <netinet6/nd6.h> 88 #endif 89 #include <security/mac/mac_framework.h> 90 91 #include <crypto/sha1.h> 92 93 #ifdef CTASSERT 94 CTASSERT(sizeof (struct ether_header) == ETHER_ADDR_LEN * 2 + 2); 95 CTASSERT(sizeof (struct ether_addr) == ETHER_ADDR_LEN); 96 #endif 97 98 VNET_DEFINE(pfil_head_t, link_pfil_head); /* Packet filter hooks */ 99 100 /* netgraph node hooks for ng_ether(4) */ 101 void (*ng_ether_input_p)(struct ifnet *ifp, struct mbuf **mp); 102 void (*ng_ether_input_orphan_p)(struct ifnet *ifp, struct mbuf *m); 103 int (*ng_ether_output_p)(struct ifnet *ifp, struct mbuf **mp); 104 void (*ng_ether_attach_p)(struct ifnet *ifp); 105 void (*ng_ether_detach_p)(struct ifnet *ifp); 106 107 void (*vlan_input_p)(struct ifnet *, struct mbuf *); 108 109 /* if_bridge(4) support */ 110 void (*bridge_dn_p)(struct mbuf *, struct ifnet *); 111 112 /* if_lagg(4) support */ 113 struct mbuf *(*lagg_input_ethernet_p)(struct ifnet *, struct mbuf *); 114 115 static const u_char etherbroadcastaddr[ETHER_ADDR_LEN] = 116 { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff }; 117 118 static int ether_resolvemulti(struct ifnet *, struct sockaddr **, 119 struct sockaddr *); 120 static int ether_requestencap(struct ifnet *, struct if_encap_req *); 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 struct ether_header *eh; 205 uint32_t lleflags = 0; 206 int error = 0; 207 #if defined(INET) || defined(INET6) 208 uint16_t etype; 209 #endif 210 211 if (plle) 212 *plle = NULL; 213 eh = (struct ether_header *)phdr; 214 215 switch (dst->sa_family) { 216 #ifdef INET 217 case AF_INET: 218 if ((m->m_flags & (M_BCAST | M_MCAST)) == 0) 219 error = arpresolve(ifp, 0, m, dst, phdr, &lleflags, 220 plle); 221 else { 222 if (m->m_flags & M_BCAST) 223 memcpy(eh->ether_dhost, ifp->if_broadcastaddr, 224 ETHER_ADDR_LEN); 225 else { 226 const struct in_addr *a; 227 a = &(((const struct sockaddr_in *)dst)->sin_addr); 228 ETHER_MAP_IP_MULTICAST(a, eh->ether_dhost); 229 } 230 etype = htons(ETHERTYPE_IP); 231 memcpy(&eh->ether_type, &etype, sizeof(etype)); 232 memcpy(eh->ether_shost, IF_LLADDR(ifp), ETHER_ADDR_LEN); 233 } 234 break; 235 #endif 236 #ifdef INET6 237 case AF_INET6: 238 if ((m->m_flags & M_MCAST) == 0) 239 error = nd6_resolve(ifp, 0, m, dst, phdr, &lleflags, 240 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_mark_used(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, dst->sa_family, 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, dst->sa_family, 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 (ntohs(eh->ether_type) == ETHERTYPE_VLAN || 446 ntohs(eh->ether_type) == ETHERTYPE_QINQ) 447 return (true); 448 449 qtag.vid = 0; 450 qtag.pcp = pcp; 451 qtag.proto = ETHERTYPE_VLAN; 452 if (ether_8021q_frame(mp, ifp, ifp, &qtag)) 453 return (true); 454 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 455 return (false); 456 } 457 458 /* 459 * Ethernet link layer output routine to send a raw frame to the device. 460 * 461 * This assumes that the 14 byte Ethernet header is present and contiguous 462 * in the first mbuf (if BRIDGE'ing). 463 */ 464 int 465 ether_output_frame(struct ifnet *ifp, struct mbuf *m) 466 { 467 uint8_t pcp; 468 469 pcp = ifp->if_pcp; 470 if (pcp != IFNET_PCP_NONE && ifp->if_type != IFT_L2VLAN && 471 !ether_set_pcp(&m, ifp, pcp)) 472 return (0); 473 474 if (PFIL_HOOKED_OUT(V_link_pfil_head)) 475 switch (pfil_run_hooks(V_link_pfil_head, &m, ifp, PFIL_OUT, 476 NULL)) { 477 case PFIL_DROPPED: 478 return (EACCES); 479 case PFIL_CONSUMED: 480 return (0); 481 } 482 483 #ifdef EXPERIMENTAL 484 #if defined(INET6) && defined(INET) 485 /* draft-ietf-6man-ipv6only-flag */ 486 /* Catch ETHERTYPE_IP, and ETHERTYPE_[REV]ARP if we are v6-only. */ 487 if ((ND_IFINFO(ifp)->flags & ND6_IFF_IPV6_ONLY_MASK) != 0) { 488 struct ether_header *eh; 489 490 eh = mtod(m, struct ether_header *); 491 switch (ntohs(eh->ether_type)) { 492 case ETHERTYPE_IP: 493 case ETHERTYPE_ARP: 494 case ETHERTYPE_REVARP: 495 m_freem(m); 496 return (EAFNOSUPPORT); 497 /* NOTREACHED */ 498 break; 499 }; 500 } 501 #endif 502 #endif 503 504 /* 505 * Queue message on interface, update output statistics if 506 * successful, and start output if interface not yet active. 507 */ 508 return ((ifp->if_transmit)(ifp, m)); 509 } 510 511 /* 512 * Process a received Ethernet packet; the packet is in the 513 * mbuf chain m with the ethernet header at the front. 514 */ 515 static void 516 ether_input_internal(struct ifnet *ifp, struct mbuf *m) 517 { 518 struct ether_header *eh; 519 u_short etype; 520 521 if ((ifp->if_flags & IFF_UP) == 0) { 522 m_freem(m); 523 return; 524 } 525 #ifdef DIAGNOSTIC 526 if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0) { 527 if_printf(ifp, "discard frame at !IFF_DRV_RUNNING\n"); 528 m_freem(m); 529 return; 530 } 531 #endif 532 if (m->m_len < ETHER_HDR_LEN) { 533 /* XXX maybe should pullup? */ 534 if_printf(ifp, "discard frame w/o leading ethernet " 535 "header (len %u pkt len %u)\n", 536 m->m_len, m->m_pkthdr.len); 537 if_inc_counter(ifp, IFCOUNTER_IERRORS, 1); 538 m_freem(m); 539 return; 540 } 541 eh = mtod(m, struct ether_header *); 542 etype = ntohs(eh->ether_type); 543 random_harvest_queue_ether(m, sizeof(*m)); 544 545 #ifdef EXPERIMENTAL 546 #if defined(INET6) && defined(INET) 547 /* draft-ietf-6man-ipv6only-flag */ 548 /* Catch ETHERTYPE_IP, and ETHERTYPE_[REV]ARP if we are v6-only. */ 549 if ((ND_IFINFO(ifp)->flags & ND6_IFF_IPV6_ONLY_MASK) != 0) { 550 switch (etype) { 551 case ETHERTYPE_IP: 552 case ETHERTYPE_ARP: 553 case ETHERTYPE_REVARP: 554 m_freem(m); 555 return; 556 /* NOTREACHED */ 557 break; 558 }; 559 } 560 #endif 561 #endif 562 563 CURVNET_SET_QUIET(ifp->if_vnet); 564 565 if (ETHER_IS_MULTICAST(eh->ether_dhost)) { 566 if (ETHER_IS_BROADCAST(eh->ether_dhost)) 567 m->m_flags |= M_BCAST; 568 else 569 m->m_flags |= M_MCAST; 570 if_inc_counter(ifp, IFCOUNTER_IMCASTS, 1); 571 } 572 573 #ifdef MAC 574 /* 575 * Tag the mbuf with an appropriate MAC label before any other 576 * consumers can get to it. 577 */ 578 mac_ifnet_create_mbuf(ifp, m); 579 #endif 580 581 /* 582 * Give bpf a chance at the packet. 583 */ 584 ETHER_BPF_MTAP(ifp, m); 585 586 /* 587 * If the CRC is still on the packet, trim it off. We do this once 588 * and once only in case we are re-entered. Nothing else on the 589 * Ethernet receive path expects to see the FCS. 590 */ 591 if (m->m_flags & M_HASFCS) { 592 m_adj(m, -ETHER_CRC_LEN); 593 m->m_flags &= ~M_HASFCS; 594 } 595 596 if (!(ifp->if_capenable & IFCAP_HWSTATS)) 597 if_inc_counter(ifp, IFCOUNTER_IBYTES, m->m_pkthdr.len); 598 599 /* Allow monitor mode to claim this frame, after stats are updated. */ 600 if (ifp->if_flags & IFF_MONITOR) { 601 m_freem(m); 602 CURVNET_RESTORE(); 603 return; 604 } 605 606 /* Handle input from a lagg(4) port */ 607 if (ifp->if_type == IFT_IEEE8023ADLAG) { 608 KASSERT(lagg_input_ethernet_p != NULL, 609 ("%s: if_lagg not loaded!", __func__)); 610 m = (*lagg_input_ethernet_p)(ifp, m); 611 if (m != NULL) 612 ifp = m->m_pkthdr.rcvif; 613 else { 614 CURVNET_RESTORE(); 615 return; 616 } 617 } 618 619 /* 620 * If the hardware did not process an 802.1Q tag, do this now, 621 * to allow 802.1P priority frames to be passed to the main input 622 * path correctly. 623 */ 624 if ((m->m_flags & M_VLANTAG) == 0 && 625 ((etype == ETHERTYPE_VLAN) || (etype == ETHERTYPE_QINQ))) { 626 struct ether_vlan_header *evl; 627 628 if (m->m_len < sizeof(*evl) && 629 (m = m_pullup(m, sizeof(*evl))) == NULL) { 630 #ifdef DIAGNOSTIC 631 if_printf(ifp, "cannot pullup VLAN header\n"); 632 #endif 633 if_inc_counter(ifp, IFCOUNTER_IERRORS, 1); 634 CURVNET_RESTORE(); 635 return; 636 } 637 638 evl = mtod(m, struct ether_vlan_header *); 639 m->m_pkthdr.ether_vtag = ntohs(evl->evl_tag); 640 m->m_flags |= M_VLANTAG; 641 642 bcopy((char *)evl, (char *)evl + ETHER_VLAN_ENCAP_LEN, 643 ETHER_HDR_LEN - ETHER_TYPE_LEN); 644 m_adj(m, ETHER_VLAN_ENCAP_LEN); 645 eh = mtod(m, struct ether_header *); 646 } 647 648 M_SETFIB(m, ifp->if_fib); 649 650 /* Allow ng_ether(4) to claim this frame. */ 651 if (ifp->if_l2com != NULL) { 652 KASSERT(ng_ether_input_p != NULL, 653 ("%s: ng_ether_input_p is NULL", __func__)); 654 m->m_flags &= ~M_PROMISC; 655 (*ng_ether_input_p)(ifp, &m); 656 if (m == NULL) { 657 CURVNET_RESTORE(); 658 return; 659 } 660 eh = mtod(m, struct ether_header *); 661 } 662 663 /* 664 * Allow if_bridge(4) to claim this frame. 665 * The BRIDGE_INPUT() macro will update ifp if the bridge changed it 666 * and the frame should be delivered locally. 667 */ 668 if (ifp->if_bridge != NULL) { 669 m->m_flags &= ~M_PROMISC; 670 BRIDGE_INPUT(ifp, m); 671 if (m == NULL) { 672 CURVNET_RESTORE(); 673 return; 674 } 675 eh = mtod(m, struct ether_header *); 676 } 677 678 #if defined(INET) || defined(INET6) 679 /* 680 * Clear M_PROMISC on frame so that carp(4) will see it when the 681 * mbuf flows up to Layer 3. 682 * FreeBSD's implementation of carp(4) uses the inprotosw 683 * to dispatch IPPROTO_CARP. carp(4) also allocates its own 684 * Ethernet addresses of the form 00:00:5e:00:01:xx, which 685 * is outside the scope of the M_PROMISC test below. 686 * TODO: Maintain a hash table of ethernet addresses other than 687 * ether_dhost which may be active on this ifp. 688 */ 689 if (ifp->if_carp && (*carp_forus_p)(ifp, eh->ether_dhost)) { 690 m->m_flags &= ~M_PROMISC; 691 } else 692 #endif 693 { 694 /* 695 * If the frame received was not for our MAC address, set the 696 * M_PROMISC flag on the mbuf chain. The frame may need to 697 * be seen by the rest of the Ethernet input path in case of 698 * re-entry (e.g. bridge, vlan, netgraph) but should not be 699 * seen by upper protocol layers. 700 */ 701 if (!ETHER_IS_MULTICAST(eh->ether_dhost) && 702 bcmp(IF_LLADDR(ifp), eh->ether_dhost, ETHER_ADDR_LEN) != 0) 703 m->m_flags |= M_PROMISC; 704 } 705 706 ether_demux(ifp, m); 707 CURVNET_RESTORE(); 708 } 709 710 /* 711 * Ethernet input dispatch; by default, direct dispatch here regardless of 712 * global configuration. However, if RSS is enabled, hook up RSS affinity 713 * so that when deferred or hybrid dispatch is enabled, we can redistribute 714 * load based on RSS. 715 * 716 * XXXRW: Would be nice if the ifnet passed up a flag indicating whether or 717 * not it had already done work distribution via multi-queue. Then we could 718 * direct dispatch in the event load balancing was already complete and 719 * handle the case of interfaces with different capabilities better. 720 * 721 * XXXRW: Sort of want an M_DISTRIBUTED flag to avoid multiple distributions 722 * at multiple layers? 723 * 724 * XXXRW: For now, enable all this only if RSS is compiled in, although it 725 * works fine without RSS. Need to characterise the performance overhead 726 * of the detour through the netisr code in the event the result is always 727 * direct dispatch. 728 */ 729 static void 730 ether_nh_input(struct mbuf *m) 731 { 732 733 M_ASSERTPKTHDR(m); 734 KASSERT(m->m_pkthdr.rcvif != NULL, 735 ("%s: NULL interface pointer", __func__)); 736 ether_input_internal(m->m_pkthdr.rcvif, m); 737 } 738 739 static struct netisr_handler ether_nh = { 740 .nh_name = "ether", 741 .nh_handler = ether_nh_input, 742 .nh_proto = NETISR_ETHER, 743 #ifdef RSS 744 .nh_policy = NETISR_POLICY_CPU, 745 .nh_dispatch = NETISR_DISPATCH_DIRECT, 746 .nh_m2cpuid = rss_m2cpuid, 747 #else 748 .nh_policy = NETISR_POLICY_SOURCE, 749 .nh_dispatch = NETISR_DISPATCH_DIRECT, 750 #endif 751 }; 752 753 static void 754 ether_init(__unused void *arg) 755 { 756 757 netisr_register(ðer_nh); 758 } 759 SYSINIT(ether, SI_SUB_INIT_IF, SI_ORDER_ANY, ether_init, NULL); 760 761 static void 762 vnet_ether_init(__unused void *arg) 763 { 764 struct pfil_head_args args; 765 766 args.pa_version = PFIL_VERSION; 767 args.pa_flags = PFIL_IN | PFIL_OUT; 768 args.pa_type = PFIL_TYPE_ETHERNET; 769 args.pa_headname = PFIL_ETHER_NAME; 770 V_link_pfil_head = pfil_head_register(&args); 771 772 #ifdef VIMAGE 773 netisr_register_vnet(ðer_nh); 774 #endif 775 } 776 VNET_SYSINIT(vnet_ether_init, SI_SUB_PROTO_IF, SI_ORDER_ANY, 777 vnet_ether_init, NULL); 778 779 #ifdef VIMAGE 780 static void 781 vnet_ether_pfil_destroy(__unused void *arg) 782 { 783 784 pfil_head_unregister(V_link_pfil_head); 785 } 786 VNET_SYSUNINIT(vnet_ether_pfil_uninit, SI_SUB_PROTO_PFIL, SI_ORDER_ANY, 787 vnet_ether_pfil_destroy, NULL); 788 789 static void 790 vnet_ether_destroy(__unused void *arg) 791 { 792 793 netisr_unregister_vnet(ðer_nh); 794 } 795 VNET_SYSUNINIT(vnet_ether_uninit, SI_SUB_PROTO_IF, SI_ORDER_ANY, 796 vnet_ether_destroy, NULL); 797 #endif 798 799 static void 800 ether_input(struct ifnet *ifp, struct mbuf *m) 801 { 802 struct epoch_tracker et; 803 struct mbuf *mn; 804 bool needs_epoch; 805 806 needs_epoch = !(ifp->if_flags & IFF_KNOWSEPOCH); 807 808 /* 809 * The drivers are allowed to pass in a chain of packets linked with 810 * m_nextpkt. We split them up into separate packets here and pass 811 * them up. This allows the drivers to amortize the receive lock. 812 */ 813 CURVNET_SET_QUIET(ifp->if_vnet); 814 if (__predict_false(needs_epoch)) 815 NET_EPOCH_ENTER(et); 816 while (m) { 817 mn = m->m_nextpkt; 818 m->m_nextpkt = NULL; 819 820 /* 821 * We will rely on rcvif being set properly in the deferred 822 * context, so assert it is correct here. 823 */ 824 MPASS((m->m_pkthdr.csum_flags & CSUM_SND_TAG) == 0); 825 KASSERT(m->m_pkthdr.rcvif == ifp, ("%s: ifnet mismatch m %p " 826 "rcvif %p ifp %p", __func__, m, m->m_pkthdr.rcvif, ifp)); 827 netisr_dispatch(NETISR_ETHER, m); 828 m = mn; 829 } 830 if (__predict_false(needs_epoch)) 831 NET_EPOCH_EXIT(et); 832 CURVNET_RESTORE(); 833 } 834 835 /* 836 * Upper layer processing for a received Ethernet packet. 837 */ 838 void 839 ether_demux(struct ifnet *ifp, struct mbuf *m) 840 { 841 struct ether_header *eh; 842 int i, isr; 843 u_short ether_type; 844 845 NET_EPOCH_ASSERT(); 846 KASSERT(ifp != NULL, ("%s: NULL interface pointer", __func__)); 847 848 /* Do not grab PROMISC frames in case we are re-entered. */ 849 if (PFIL_HOOKED_IN(V_link_pfil_head) && !(m->m_flags & M_PROMISC)) { 850 i = pfil_run_hooks(V_link_pfil_head, &m, ifp, PFIL_IN, NULL); 851 if (i != 0 || m == NULL) 852 return; 853 } 854 855 eh = mtod(m, struct ether_header *); 856 ether_type = ntohs(eh->ether_type); 857 858 /* 859 * If this frame has a VLAN tag other than 0, call vlan_input() 860 * if its module is loaded. Otherwise, drop. 861 */ 862 if ((m->m_flags & M_VLANTAG) && 863 EVL_VLANOFTAG(m->m_pkthdr.ether_vtag) != 0) { 864 if (ifp->if_vlantrunk == NULL) { 865 if_inc_counter(ifp, IFCOUNTER_NOPROTO, 1); 866 m_freem(m); 867 return; 868 } 869 KASSERT(vlan_input_p != NULL,("%s: VLAN not loaded!", 870 __func__)); 871 /* Clear before possibly re-entering ether_input(). */ 872 m->m_flags &= ~M_PROMISC; 873 (*vlan_input_p)(ifp, m); 874 return; 875 } 876 877 /* 878 * Pass promiscuously received frames to the upper layer if the user 879 * requested this by setting IFF_PPROMISC. Otherwise, drop them. 880 */ 881 if ((ifp->if_flags & IFF_PPROMISC) == 0 && (m->m_flags & M_PROMISC)) { 882 m_freem(m); 883 return; 884 } 885 886 /* 887 * Reset layer specific mbuf flags to avoid confusing upper layers. 888 * Strip off Ethernet header. 889 */ 890 m->m_flags &= ~M_VLANTAG; 891 m_clrprotoflags(m); 892 m_adj(m, ETHER_HDR_LEN); 893 894 /* 895 * Dispatch frame to upper layer. 896 */ 897 switch (ether_type) { 898 #ifdef INET 899 case ETHERTYPE_IP: 900 isr = NETISR_IP; 901 break; 902 903 case ETHERTYPE_ARP: 904 if (ifp->if_flags & IFF_NOARP) { 905 /* Discard packet if ARP is disabled on interface */ 906 m_freem(m); 907 return; 908 } 909 isr = NETISR_ARP; 910 break; 911 #endif 912 #ifdef INET6 913 case ETHERTYPE_IPV6: 914 isr = NETISR_IPV6; 915 break; 916 #endif 917 default: 918 goto discard; 919 } 920 netisr_dispatch(isr, m); 921 return; 922 923 discard: 924 /* 925 * Packet is to be discarded. If netgraph is present, 926 * hand the packet to it for last chance processing; 927 * otherwise dispose of it. 928 */ 929 if (ifp->if_l2com != NULL) { 930 KASSERT(ng_ether_input_orphan_p != NULL, 931 ("ng_ether_input_orphan_p is NULL")); 932 /* 933 * Put back the ethernet header so netgraph has a 934 * consistent view of inbound packets. 935 */ 936 M_PREPEND(m, ETHER_HDR_LEN, M_NOWAIT); 937 (*ng_ether_input_orphan_p)(ifp, m); 938 return; 939 } 940 m_freem(m); 941 } 942 943 /* 944 * Convert Ethernet address to printable (loggable) representation. 945 * This routine is for compatibility; it's better to just use 946 * 947 * printf("%6D", <pointer to address>, ":"); 948 * 949 * since there's no static buffer involved. 950 */ 951 char * 952 ether_sprintf(const u_char *ap) 953 { 954 static char etherbuf[18]; 955 snprintf(etherbuf, sizeof (etherbuf), "%6D", ap, ":"); 956 return (etherbuf); 957 } 958 959 /* 960 * Perform common duties while attaching to interface list 961 */ 962 void 963 ether_ifattach(struct ifnet *ifp, const u_int8_t *lla) 964 { 965 int i; 966 struct ifaddr *ifa; 967 struct sockaddr_dl *sdl; 968 969 ifp->if_addrlen = ETHER_ADDR_LEN; 970 ifp->if_hdrlen = ETHER_HDR_LEN; 971 ifp->if_mtu = ETHERMTU; 972 if_attach(ifp); 973 ifp->if_output = ether_output; 974 ifp->if_input = ether_input; 975 ifp->if_resolvemulti = ether_resolvemulti; 976 ifp->if_requestencap = ether_requestencap; 977 #ifdef VIMAGE 978 ifp->if_reassign = ether_reassign; 979 #endif 980 if (ifp->if_baudrate == 0) 981 ifp->if_baudrate = IF_Mbps(10); /* just a default */ 982 ifp->if_broadcastaddr = etherbroadcastaddr; 983 984 ifa = ifp->if_addr; 985 KASSERT(ifa != NULL, ("%s: no lladdr!\n", __func__)); 986 sdl = (struct sockaddr_dl *)ifa->ifa_addr; 987 sdl->sdl_type = IFT_ETHER; 988 sdl->sdl_alen = ifp->if_addrlen; 989 bcopy(lla, LLADDR(sdl), ifp->if_addrlen); 990 991 if (ifp->if_hw_addr != NULL) 992 bcopy(lla, ifp->if_hw_addr, ifp->if_addrlen); 993 994 bpfattach(ifp, DLT_EN10MB, ETHER_HDR_LEN); 995 if (ng_ether_attach_p != NULL) 996 (*ng_ether_attach_p)(ifp); 997 998 /* Announce Ethernet MAC address if non-zero. */ 999 for (i = 0; i < ifp->if_addrlen; i++) 1000 if (lla[i] != 0) 1001 break; 1002 if (i != ifp->if_addrlen) 1003 if_printf(ifp, "Ethernet address: %6D\n", lla, ":"); 1004 1005 uuid_ether_add(LLADDR(sdl)); 1006 1007 /* Add necessary bits are setup; announce it now. */ 1008 EVENTHANDLER_INVOKE(ether_ifattach_event, ifp); 1009 if (IS_DEFAULT_VNET(curvnet)) 1010 devctl_notify("ETHERNET", ifp->if_xname, "IFATTACH", NULL); 1011 } 1012 1013 /* 1014 * Perform common duties while detaching an Ethernet interface 1015 */ 1016 void 1017 ether_ifdetach(struct ifnet *ifp) 1018 { 1019 struct sockaddr_dl *sdl; 1020 1021 sdl = (struct sockaddr_dl *)(ifp->if_addr->ifa_addr); 1022 uuid_ether_del(LLADDR(sdl)); 1023 1024 if (ifp->if_l2com != NULL) { 1025 KASSERT(ng_ether_detach_p != NULL, 1026 ("ng_ether_detach_p is NULL")); 1027 (*ng_ether_detach_p)(ifp); 1028 } 1029 1030 bpfdetach(ifp); 1031 if_detach(ifp); 1032 } 1033 1034 #ifdef VIMAGE 1035 void 1036 ether_reassign(struct ifnet *ifp, struct vnet *new_vnet, char *unused __unused) 1037 { 1038 1039 if (ifp->if_l2com != NULL) { 1040 KASSERT(ng_ether_detach_p != NULL, 1041 ("ng_ether_detach_p is NULL")); 1042 (*ng_ether_detach_p)(ifp); 1043 } 1044 1045 if (ng_ether_attach_p != NULL) { 1046 CURVNET_SET_QUIET(new_vnet); 1047 (*ng_ether_attach_p)(ifp); 1048 CURVNET_RESTORE(); 1049 } 1050 } 1051 #endif 1052 1053 SYSCTL_DECL(_net_link); 1054 SYSCTL_NODE(_net_link, IFT_ETHER, ether, CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 1055 "Ethernet"); 1056 1057 #if 0 1058 /* 1059 * This is for reference. We have a table-driven version 1060 * of the little-endian crc32 generator, which is faster 1061 * than the double-loop. 1062 */ 1063 uint32_t 1064 ether_crc32_le(const uint8_t *buf, size_t len) 1065 { 1066 size_t i; 1067 uint32_t crc; 1068 int bit; 1069 uint8_t data; 1070 1071 crc = 0xffffffff; /* initial value */ 1072 1073 for (i = 0; i < len; i++) { 1074 for (data = *buf++, bit = 0; bit < 8; bit++, data >>= 1) { 1075 carry = (crc ^ data) & 1; 1076 crc >>= 1; 1077 if (carry) 1078 crc = (crc ^ ETHER_CRC_POLY_LE); 1079 } 1080 } 1081 1082 return (crc); 1083 } 1084 #else 1085 uint32_t 1086 ether_crc32_le(const uint8_t *buf, size_t len) 1087 { 1088 static const uint32_t crctab[] = { 1089 0x00000000, 0x1db71064, 0x3b6e20c8, 0x26d930ac, 1090 0x76dc4190, 0x6b6b51f4, 0x4db26158, 0x5005713c, 1091 0xedb88320, 0xf00f9344, 0xd6d6a3e8, 0xcb61b38c, 1092 0x9b64c2b0, 0x86d3d2d4, 0xa00ae278, 0xbdbdf21c 1093 }; 1094 size_t i; 1095 uint32_t crc; 1096 1097 crc = 0xffffffff; /* initial value */ 1098 1099 for (i = 0; i < len; i++) { 1100 crc ^= buf[i]; 1101 crc = (crc >> 4) ^ crctab[crc & 0xf]; 1102 crc = (crc >> 4) ^ crctab[crc & 0xf]; 1103 } 1104 1105 return (crc); 1106 } 1107 #endif 1108 1109 uint32_t 1110 ether_crc32_be(const uint8_t *buf, size_t len) 1111 { 1112 size_t i; 1113 uint32_t crc, carry; 1114 int bit; 1115 uint8_t data; 1116 1117 crc = 0xffffffff; /* initial value */ 1118 1119 for (i = 0; i < len; i++) { 1120 for (data = *buf++, bit = 0; bit < 8; bit++, data >>= 1) { 1121 carry = ((crc & 0x80000000) ? 1 : 0) ^ (data & 0x01); 1122 crc <<= 1; 1123 if (carry) 1124 crc = (crc ^ ETHER_CRC_POLY_BE) | carry; 1125 } 1126 } 1127 1128 return (crc); 1129 } 1130 1131 int 1132 ether_ioctl(struct ifnet *ifp, u_long command, caddr_t data) 1133 { 1134 struct ifaddr *ifa = (struct ifaddr *) data; 1135 struct ifreq *ifr = (struct ifreq *) data; 1136 int error = 0; 1137 1138 switch (command) { 1139 case SIOCSIFADDR: 1140 ifp->if_flags |= IFF_UP; 1141 1142 switch (ifa->ifa_addr->sa_family) { 1143 #ifdef INET 1144 case AF_INET: 1145 ifp->if_init(ifp->if_softc); /* before arpwhohas */ 1146 arp_ifinit(ifp, ifa); 1147 break; 1148 #endif 1149 default: 1150 ifp->if_init(ifp->if_softc); 1151 break; 1152 } 1153 break; 1154 1155 case SIOCGIFADDR: 1156 bcopy(IF_LLADDR(ifp), &ifr->ifr_addr.sa_data[0], 1157 ETHER_ADDR_LEN); 1158 break; 1159 1160 case SIOCSIFMTU: 1161 /* 1162 * Set the interface MTU. 1163 */ 1164 if (ifr->ifr_mtu > ETHERMTU) { 1165 error = EINVAL; 1166 } else { 1167 ifp->if_mtu = ifr->ifr_mtu; 1168 } 1169 break; 1170 1171 case SIOCSLANPCP: 1172 error = priv_check(curthread, PRIV_NET_SETLANPCP); 1173 if (error != 0) 1174 break; 1175 if (ifr->ifr_lan_pcp > 7 && 1176 ifr->ifr_lan_pcp != IFNET_PCP_NONE) { 1177 error = EINVAL; 1178 } else { 1179 ifp->if_pcp = ifr->ifr_lan_pcp; 1180 /* broadcast event about PCP change */ 1181 EVENTHANDLER_INVOKE(ifnet_event, ifp, IFNET_EVENT_PCP); 1182 } 1183 break; 1184 1185 case SIOCGLANPCP: 1186 ifr->ifr_lan_pcp = ifp->if_pcp; 1187 break; 1188 1189 default: 1190 error = EINVAL; /* XXX netbsd has ENOTTY??? */ 1191 break; 1192 } 1193 return (error); 1194 } 1195 1196 static int 1197 ether_resolvemulti(struct ifnet *ifp, struct sockaddr **llsa, 1198 struct sockaddr *sa) 1199 { 1200 struct sockaddr_dl *sdl; 1201 #ifdef INET 1202 struct sockaddr_in *sin; 1203 #endif 1204 #ifdef INET6 1205 struct sockaddr_in6 *sin6; 1206 #endif 1207 u_char *e_addr; 1208 1209 switch(sa->sa_family) { 1210 case AF_LINK: 1211 /* 1212 * No mapping needed. Just check that it's a valid MC address. 1213 */ 1214 sdl = (struct sockaddr_dl *)sa; 1215 e_addr = LLADDR(sdl); 1216 if (!ETHER_IS_MULTICAST(e_addr)) 1217 return EADDRNOTAVAIL; 1218 *llsa = NULL; 1219 return 0; 1220 1221 #ifdef INET 1222 case AF_INET: 1223 sin = (struct sockaddr_in *)sa; 1224 if (!IN_MULTICAST(ntohl(sin->sin_addr.s_addr))) 1225 return EADDRNOTAVAIL; 1226 sdl = link_init_sdl(ifp, *llsa, IFT_ETHER); 1227 sdl->sdl_alen = ETHER_ADDR_LEN; 1228 e_addr = LLADDR(sdl); 1229 ETHER_MAP_IP_MULTICAST(&sin->sin_addr, e_addr); 1230 *llsa = (struct sockaddr *)sdl; 1231 return 0; 1232 #endif 1233 #ifdef INET6 1234 case AF_INET6: 1235 sin6 = (struct sockaddr_in6 *)sa; 1236 if (IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr)) { 1237 /* 1238 * An IP6 address of 0 means listen to all 1239 * of the Ethernet multicast address used for IP6. 1240 * (This is used for multicast routers.) 1241 */ 1242 ifp->if_flags |= IFF_ALLMULTI; 1243 *llsa = NULL; 1244 return 0; 1245 } 1246 if (!IN6_IS_ADDR_MULTICAST(&sin6->sin6_addr)) 1247 return EADDRNOTAVAIL; 1248 sdl = link_init_sdl(ifp, *llsa, IFT_ETHER); 1249 sdl->sdl_alen = ETHER_ADDR_LEN; 1250 e_addr = LLADDR(sdl); 1251 ETHER_MAP_IPV6_MULTICAST(&sin6->sin6_addr, e_addr); 1252 *llsa = (struct sockaddr *)sdl; 1253 return 0; 1254 #endif 1255 1256 default: 1257 /* 1258 * Well, the text isn't quite right, but it's the name 1259 * that counts... 1260 */ 1261 return EAFNOSUPPORT; 1262 } 1263 } 1264 1265 static moduledata_t ether_mod = { 1266 .name = "ether", 1267 }; 1268 1269 void 1270 ether_vlan_mtap(struct bpf_if *bp, struct mbuf *m, void *data, u_int dlen) 1271 { 1272 struct ether_vlan_header vlan; 1273 struct mbuf mv, mb; 1274 1275 KASSERT((m->m_flags & M_VLANTAG) != 0, 1276 ("%s: vlan information not present", __func__)); 1277 KASSERT(m->m_len >= sizeof(struct ether_header), 1278 ("%s: mbuf not large enough for header", __func__)); 1279 bcopy(mtod(m, char *), &vlan, sizeof(struct ether_header)); 1280 vlan.evl_proto = vlan.evl_encap_proto; 1281 vlan.evl_encap_proto = htons(ETHERTYPE_VLAN); 1282 vlan.evl_tag = htons(m->m_pkthdr.ether_vtag); 1283 m->m_len -= sizeof(struct ether_header); 1284 m->m_data += sizeof(struct ether_header); 1285 /* 1286 * If a data link has been supplied by the caller, then we will need to 1287 * re-create a stack allocated mbuf chain with the following structure: 1288 * 1289 * (1) mbuf #1 will contain the supplied data link 1290 * (2) mbuf #2 will contain the vlan header 1291 * (3) mbuf #3 will contain the original mbuf's packet data 1292 * 1293 * Otherwise, submit the packet and vlan header via bpf_mtap2(). 1294 */ 1295 if (data != NULL) { 1296 mv.m_next = m; 1297 mv.m_data = (caddr_t)&vlan; 1298 mv.m_len = sizeof(vlan); 1299 mb.m_next = &mv; 1300 mb.m_data = data; 1301 mb.m_len = dlen; 1302 bpf_mtap(bp, &mb); 1303 } else 1304 bpf_mtap2(bp, &vlan, sizeof(vlan), m); 1305 m->m_len += sizeof(struct ether_header); 1306 m->m_data -= sizeof(struct ether_header); 1307 } 1308 1309 struct mbuf * 1310 ether_vlanencap_proto(struct mbuf *m, uint16_t tag, uint16_t proto) 1311 { 1312 struct ether_vlan_header *evl; 1313 1314 M_PREPEND(m, ETHER_VLAN_ENCAP_LEN, M_NOWAIT); 1315 if (m == NULL) 1316 return (NULL); 1317 /* M_PREPEND takes care of m_len, m_pkthdr.len for us */ 1318 1319 if (m->m_len < sizeof(*evl)) { 1320 m = m_pullup(m, sizeof(*evl)); 1321 if (m == NULL) 1322 return (NULL); 1323 } 1324 1325 /* 1326 * Transform the Ethernet header into an Ethernet header 1327 * with 802.1Q encapsulation. 1328 */ 1329 evl = mtod(m, struct ether_vlan_header *); 1330 bcopy((char *)evl + ETHER_VLAN_ENCAP_LEN, 1331 (char *)evl, ETHER_HDR_LEN - ETHER_TYPE_LEN); 1332 evl->evl_encap_proto = htons(proto); 1333 evl->evl_tag = htons(tag); 1334 return (m); 1335 } 1336 1337 static SYSCTL_NODE(_net_link, IFT_L2VLAN, vlan, CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 1338 "IEEE 802.1Q VLAN"); 1339 static SYSCTL_NODE(_net_link_vlan, PF_LINK, link, 1340 CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 1341 "for consistency"); 1342 1343 VNET_DEFINE_STATIC(int, soft_pad); 1344 #define V_soft_pad VNET(soft_pad) 1345 SYSCTL_INT(_net_link_vlan, OID_AUTO, soft_pad, CTLFLAG_RW | CTLFLAG_VNET, 1346 &VNET_NAME(soft_pad), 0, 1347 "pad short frames before tagging"); 1348 1349 /* 1350 * For now, make preserving PCP via an mbuf tag optional, as it increases 1351 * per-packet memory allocations and frees. In the future, it would be 1352 * preferable to reuse ether_vtag for this, or similar. 1353 */ 1354 int vlan_mtag_pcp = 0; 1355 SYSCTL_INT(_net_link_vlan, OID_AUTO, mtag_pcp, CTLFLAG_RW, 1356 &vlan_mtag_pcp, 0, 1357 "Retain VLAN PCP information as packets are passed up the stack"); 1358 1359 bool 1360 ether_8021q_frame(struct mbuf **mp, struct ifnet *ife, struct ifnet *p, 1361 struct ether_8021q_tag *qtag) 1362 { 1363 struct m_tag *mtag; 1364 int n; 1365 uint16_t tag; 1366 static const char pad[8]; /* just zeros */ 1367 1368 /* 1369 * Pad the frame to the minimum size allowed if told to. 1370 * This option is in accord with IEEE Std 802.1Q, 2003 Ed., 1371 * paragraph C.4.4.3.b. It can help to work around buggy 1372 * bridges that violate paragraph C.4.4.3.a from the same 1373 * document, i.e., fail to pad short frames after untagging. 1374 * E.g., a tagged frame 66 bytes long (incl. FCS) is OK, but 1375 * untagging it will produce a 62-byte frame, which is a runt 1376 * and requires padding. There are VLAN-enabled network 1377 * devices that just discard such runts instead or mishandle 1378 * them somehow. 1379 */ 1380 if (V_soft_pad && p->if_type == IFT_ETHER) { 1381 for (n = ETHERMIN + ETHER_HDR_LEN - (*mp)->m_pkthdr.len; 1382 n > 0; n -= sizeof(pad)) { 1383 if (!m_append(*mp, min(n, sizeof(pad)), pad)) 1384 break; 1385 } 1386 if (n > 0) { 1387 m_freem(*mp); 1388 *mp = NULL; 1389 if_printf(ife, "cannot pad short frame"); 1390 return (false); 1391 } 1392 } 1393 1394 /* 1395 * If PCP is set in mbuf, use it 1396 */ 1397 if ((*mp)->m_flags & M_VLANTAG) { 1398 qtag->pcp = EVL_PRIOFTAG((*mp)->m_pkthdr.ether_vtag); 1399 } 1400 1401 /* 1402 * If underlying interface can do VLAN tag insertion itself, 1403 * just pass the packet along. However, we need some way to 1404 * tell the interface where the packet came from so that it 1405 * knows how to find the VLAN tag to use, so we attach a 1406 * packet tag that holds it. 1407 */ 1408 if (vlan_mtag_pcp && (mtag = m_tag_locate(*mp, MTAG_8021Q, 1409 MTAG_8021Q_PCP_OUT, NULL)) != NULL) 1410 tag = EVL_MAKETAG(qtag->vid, *(uint8_t *)(mtag + 1), 0); 1411 else 1412 tag = EVL_MAKETAG(qtag->vid, qtag->pcp, 0); 1413 if ((p->if_capenable & IFCAP_VLAN_HWTAGGING) && 1414 (qtag->proto == ETHERTYPE_VLAN)) { 1415 (*mp)->m_pkthdr.ether_vtag = tag; 1416 (*mp)->m_flags |= M_VLANTAG; 1417 } else { 1418 *mp = ether_vlanencap_proto(*mp, tag, qtag->proto); 1419 if (*mp == NULL) { 1420 if_printf(ife, "unable to prepend 802.1Q header"); 1421 return (false); 1422 } 1423 } 1424 return (true); 1425 } 1426 1427 /* 1428 * Allocate an address from the FreeBSD Foundation OUI. This uses a 1429 * cryptographic hash function on the containing jail's name, UUID and the 1430 * interface name to attempt to provide a unique but stable address. 1431 * Pseudo-interfaces which require a MAC address should use this function to 1432 * allocate non-locally-administered addresses. 1433 */ 1434 void 1435 ether_gen_addr(struct ifnet *ifp, struct ether_addr *hwaddr) 1436 { 1437 SHA1_CTX ctx; 1438 char *buf; 1439 char uuid[HOSTUUIDLEN + 1]; 1440 uint64_t addr; 1441 int i, sz; 1442 char digest[SHA1_RESULTLEN]; 1443 char jailname[MAXHOSTNAMELEN]; 1444 1445 getcredhostuuid(curthread->td_ucred, uuid, sizeof(uuid)); 1446 if (strncmp(uuid, DEFAULT_HOSTUUID, sizeof(uuid)) == 0) { 1447 /* Fall back to a random mac address. */ 1448 goto rando; 1449 } 1450 1451 /* If each (vnet) jail would also have a unique hostuuid this would not 1452 * be necessary. */ 1453 getjailname(curthread->td_ucred, jailname, sizeof(jailname)); 1454 sz = asprintf(&buf, M_TEMP, "%s-%s-%s", uuid, if_name(ifp), 1455 jailname); 1456 if (sz < 0) { 1457 /* Fall back to a random mac address. */ 1458 goto rando; 1459 } 1460 1461 SHA1Init(&ctx); 1462 SHA1Update(&ctx, buf, sz); 1463 SHA1Final(digest, &ctx); 1464 free(buf, M_TEMP); 1465 1466 addr = ((digest[0] << 16) | (digest[1] << 8) | digest[2]) & 1467 OUI_FREEBSD_GENERATED_MASK; 1468 addr = OUI_FREEBSD(addr); 1469 for (i = 0; i < ETHER_ADDR_LEN; ++i) { 1470 hwaddr->octet[i] = addr >> ((ETHER_ADDR_LEN - i - 1) * 8) & 1471 0xFF; 1472 } 1473 1474 return; 1475 rando: 1476 arc4rand(hwaddr, sizeof(*hwaddr), 0); 1477 /* Unicast */ 1478 hwaddr->octet[0] &= 0xFE; 1479 /* Locally administered. */ 1480 hwaddr->octet[0] |= 0x02; 1481 } 1482 1483 DECLARE_MODULE(ether, ether_mod, SI_SUB_INIT_IF, SI_ORDER_ANY); 1484 MODULE_VERSION(ether, 1); 1485