1/*- 2 * Copyright (c) 1982, 1989, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 4. Neither the name of the University nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * @(#)if_ethersubr.c 8.1 (Berkeley) 6/10/93 30 * $FreeBSD: stable/11/sys/net/if_ethersubr.c 360299 2020-04-25 12:49:48Z kp $ 31 */ 32 33#include "opt_inet.h" 34#include "opt_inet6.h" 35#include "opt_netgraph.h" 36#include "opt_mbuf_profiling.h" 37#include "opt_rss.h" 38 39#include <sys/param.h> 40#include <sys/systm.h> 41#include <sys/bus.h> 42#include <sys/eventhandler.h> 43#include <sys/jail.h> 44#include <sys/kernel.h> 45#include <sys/lock.h> 46#include <sys/malloc.h> 47#include <sys/module.h> 48#include <sys/mbuf.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 57#include <net/ieee_oui.h> 58#include <net/if.h> 59#include <net/if_var.h> 60#include <net/if_arp.h> 61#include <net/netisr.h> 62#include <net/route.h> 63#include <net/if_llc.h> 64#include <net/if_dl.h> 65#include <net/if_types.h> 66#include <net/bpf.h> 67#include <net/ethernet.h> 68#include <net/if_bridgevar.h> 69#include <net/if_vlan_var.h> 70#include <net/if_llatbl.h> 71#include <net/pfil.h> 72#include <net/rss_config.h> 73#include <net/vnet.h> 74 75#include <netpfil/pf/pf_mtag.h> 76 77#if defined(INET) || defined(INET6) 78#include <netinet/in.h> 79#include <netinet/in_var.h> 80#include <netinet/if_ether.h> 81#include <netinet/ip_carp.h> 82#include <netinet/ip_var.h> 83#endif 84#ifdef INET6 85#include <netinet6/nd6.h> 86#endif 87#include <security/mac/mac_framework.h> 88 89#include <crypto/sha1.h> 90 91#ifdef CTASSERT 92CTASSERT(sizeof (struct ether_header) == ETHER_ADDR_LEN * 2 + 2); 93CTASSERT(sizeof (struct ether_addr) == ETHER_ADDR_LEN); 94#endif 95 96VNET_DEFINE(struct pfil_head, link_pfil_hook); /* Packet filter hooks */ 97 98/* netgraph node hooks for ng_ether(4) */ 99void (*ng_ether_input_p)(struct ifnet *ifp, struct mbuf **mp); 100void (*ng_ether_input_orphan_p)(struct ifnet *ifp, struct mbuf *m); 101int (*ng_ether_output_p)(struct ifnet *ifp, struct mbuf **mp); 102void (*ng_ether_attach_p)(struct ifnet *ifp); 103void (*ng_ether_detach_p)(struct ifnet *ifp); 104 105void (*vlan_input_p)(struct ifnet *, struct mbuf *); 106 107/* if_bridge(4) support */ 108struct mbuf *(*bridge_input_p)(struct ifnet *, struct mbuf *); 109int (*bridge_output_p)(struct ifnet *, struct mbuf *, 110 struct sockaddr *, struct rtentry *); 111void (*bridge_dn_p)(struct mbuf *, struct ifnet *); 112 113/* if_lagg(4) support */ 114struct mbuf *(*lagg_input_p)(struct ifnet *, struct mbuf *); 115 116static const u_char etherbroadcastaddr[ETHER_ADDR_LEN] = 117 { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff }; 118 119static int ether_resolvemulti(struct ifnet *, struct sockaddr **, 120 struct sockaddr *); 121#ifdef VIMAGE 122static void ether_reassign(struct ifnet *, struct vnet *, char *); 123#endif 124static int ether_requestencap(struct ifnet *, struct if_encap_req *); 125 126 127#define senderr(e) do { error = (e); goto bad;} while (0) 128 129static void 130update_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 */ 148static int 149ether_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 205static int 206ether_resolve_addr(struct ifnet *ifp, struct mbuf *m, 207 const struct sockaddr *dst, struct route *ro, u_char *phdr, 208 uint32_t *pflags, struct llentry **plle) 209{ 210 struct ether_header *eh; 211 uint32_t lleflags = 0; 212 int error = 0; 213#if defined(INET) || defined(INET6) 214 uint16_t etype; 215#endif 216 217 if (plle) 218 *plle = NULL; 219 eh = (struct ether_header *)phdr; 220 221 switch (dst->sa_family) { 222#ifdef INET 223 case AF_INET: 224 if ((m->m_flags & (M_BCAST | M_MCAST)) == 0) 225 error = arpresolve(ifp, 0, m, dst, phdr, &lleflags, 226 plle); 227 else { 228 if (m->m_flags & M_BCAST) 229 memcpy(eh->ether_dhost, ifp->if_broadcastaddr, 230 ETHER_ADDR_LEN); 231 else { 232 const struct in_addr *a; 233 a = &(((const struct sockaddr_in *)dst)->sin_addr); 234 ETHER_MAP_IP_MULTICAST(a, eh->ether_dhost); 235 } 236 etype = htons(ETHERTYPE_IP); 237 memcpy(&eh->ether_type, &etype, sizeof(etype)); 238 memcpy(eh->ether_shost, IF_LLADDR(ifp), ETHER_ADDR_LEN); 239 } 240 break; 241#endif 242#ifdef INET6 243 case AF_INET6: 244 if ((m->m_flags & M_MCAST) == 0) 245 error = nd6_resolve(ifp, 0, m, dst, phdr, &lleflags, 246 plle); 247 else { 248 const struct in6_addr *a6; 249 a6 = &(((const struct sockaddr_in6 *)dst)->sin6_addr); 250 ETHER_MAP_IPV6_MULTICAST(a6, eh->ether_dhost); 251 etype = htons(ETHERTYPE_IPV6); 252 memcpy(&eh->ether_type, &etype, sizeof(etype)); 253 memcpy(eh->ether_shost, IF_LLADDR(ifp), ETHER_ADDR_LEN); 254 } 255 break; 256#endif 257 default: 258 if_printf(ifp, "can't handle af%d\n", dst->sa_family); 259 if (m != NULL) 260 m_freem(m); 261 return (EAFNOSUPPORT); 262 } 263 264 if (error == EHOSTDOWN) { 265 if (ro != NULL && (ro->ro_flags & RT_HAS_GW) != 0) 266 error = EHOSTUNREACH; 267 } 268 269 if (error != 0) 270 return (error); 271 272 *pflags = RT_MAY_LOOP; 273 if (lleflags & LLE_IFADDR) 274 *pflags |= RT_L2_ME; 275 276 return (0); 277} 278 279/* 280 * Ethernet output routine. 281 * Encapsulate a packet of type family for the local net. 282 * Use trailer local net encapsulation if enough data in first 283 * packet leaves a multiple of 512 bytes of data in remainder. 284 */ 285int 286ether_output(struct ifnet *ifp, struct mbuf *m, 287 const struct sockaddr *dst, struct route *ro) 288{ 289 int error = 0; 290 char linkhdr[ETHER_HDR_LEN], *phdr; 291 struct ether_header *eh; 292 struct pf_mtag *t; 293 int loop_copy = 1; 294 int hlen; /* link layer header length */ 295 uint32_t pflags; 296 struct llentry *lle = NULL; 297 struct rtentry *rt0 = NULL; 298 int addref = 0; 299 300 phdr = NULL; 301 pflags = 0; 302 if (ro != NULL) { 303 /* XXX BPF uses ro_prepend */ 304 if (ro->ro_prepend != NULL) { 305 phdr = ro->ro_prepend; 306 hlen = ro->ro_plen; 307 } else if (!(m->m_flags & (M_BCAST | M_MCAST))) { 308 if ((ro->ro_flags & RT_LLE_CACHE) != 0) { 309 lle = ro->ro_lle; 310 if (lle != NULL && 311 (lle->la_flags & LLE_VALID) == 0) { 312 LLE_FREE(lle); 313 lle = NULL; /* redundant */ 314 ro->ro_lle = NULL; 315 } 316 if (lle == NULL) { 317 /* if we lookup, keep cache */ 318 addref = 1; 319 } else 320 /* 321 * Notify LLE code that 322 * the entry was used 323 * by datapath. 324 */ 325 llentry_mark_used(lle); 326 } 327 if (lle != NULL) { 328 phdr = lle->r_linkdata; 329 hlen = lle->r_hdrlen; 330 pflags = lle->r_flags; 331 } 332 } 333 rt0 = ro->ro_rt; 334 } 335 336#ifdef MAC 337 error = mac_ifnet_check_transmit(ifp, m); 338 if (error) 339 senderr(error); 340#endif 341 342 M_PROFILE(m); 343 if (ifp->if_flags & IFF_MONITOR) 344 senderr(ENETDOWN); 345 if (!((ifp->if_flags & IFF_UP) && 346 (ifp->if_drv_flags & IFF_DRV_RUNNING))) 347 senderr(ENETDOWN); 348 349 if (phdr == NULL) { 350 /* No prepend data supplied. Try to calculate ourselves. */ 351 phdr = linkhdr; 352 hlen = ETHER_HDR_LEN; 353 error = ether_resolve_addr(ifp, m, dst, ro, phdr, &pflags, 354 addref ? &lle : NULL); 355 if (addref && lle != NULL) 356 ro->ro_lle = lle; 357 if (error != 0) 358 return (error == EWOULDBLOCK ? 0 : error); 359 } 360 361 if ((pflags & RT_L2_ME) != 0) { 362 update_mbuf_csumflags(m, m); 363 return (if_simloop(ifp, m, dst->sa_family, 0)); 364 } 365 loop_copy = pflags & RT_MAY_LOOP; 366 367 /* 368 * Add local net header. If no space in first mbuf, 369 * allocate another. 370 * 371 * Note that we do prepend regardless of RT_HAS_HEADER flag. 372 * This is done because BPF code shifts m_data pointer 373 * to the end of ethernet header prior to calling if_output(). 374 */ 375 M_PREPEND(m, hlen, M_NOWAIT); 376 if (m == NULL) 377 senderr(ENOBUFS); 378 if ((pflags & RT_HAS_HEADER) == 0) { 379 eh = mtod(m, struct ether_header *); 380 memcpy(eh, phdr, hlen); 381 } 382 383 /* 384 * If a simplex interface, and the packet is being sent to our 385 * Ethernet address or a broadcast address, loopback a copy. 386 * XXX To make a simplex device behave exactly like a duplex 387 * device, we should copy in the case of sending to our own 388 * ethernet address (thus letting the original actually appear 389 * on the wire). However, we don't do that here for security 390 * reasons and compatibility with the original behavior. 391 */ 392 if ((m->m_flags & M_BCAST) && loop_copy && (ifp->if_flags & IFF_SIMPLEX) && 393 ((t = pf_find_mtag(m)) == NULL || !t->routed)) { 394 struct mbuf *n; 395 396 /* 397 * Because if_simloop() modifies the packet, we need a 398 * writable copy through m_dup() instead of a readonly 399 * one as m_copy[m] would give us. The alternative would 400 * be to modify if_simloop() to handle the readonly mbuf, 401 * but performancewise it is mostly equivalent (trading 402 * extra data copying vs. extra locking). 403 * 404 * XXX This is a local workaround. A number of less 405 * often used kernel parts suffer from the same bug. 406 * See PR kern/105943 for a proposed general solution. 407 */ 408 if ((n = m_dup(m, M_NOWAIT)) != NULL) { 409 update_mbuf_csumflags(m, n); 410 (void)if_simloop(ifp, n, dst->sa_family, hlen); 411 } else 412 if_inc_counter(ifp, IFCOUNTER_IQDROPS, 1); 413 } 414 415 /* 416 * Bridges require special output handling. 417 */ 418 if (ifp->if_bridge) { 419 BRIDGE_OUTPUT(ifp, m, error); 420 return (error); 421 } 422 423#if defined(INET) || defined(INET6) 424 if (ifp->if_carp && 425 (error = (*carp_output_p)(ifp, m, dst))) 426 goto bad; 427#endif 428 429 /* Handle ng_ether(4) processing, if any */ 430 if (ifp->if_l2com != NULL) { 431 KASSERT(ng_ether_output_p != NULL, 432 ("ng_ether_output_p is NULL")); 433 if ((error = (*ng_ether_output_p)(ifp, &m)) != 0) { 434bad: if (m != NULL) 435 m_freem(m); 436 return (error); 437 } 438 if (m == NULL) 439 return (0); 440 } 441 442 /* Continue with link-layer output */ 443 return ether_output_frame(ifp, m); 444} 445 446static bool 447ether_set_pcp(struct mbuf **mp, struct ifnet *ifp, uint8_t pcp) 448{ 449 struct ether_header *eh; 450 451 eh = mtod(*mp, struct ether_header *); 452 if (ntohs(eh->ether_type) == ETHERTYPE_VLAN || 453 ether_8021q_frame(mp, ifp, ifp, 0, pcp)) 454 return (true); 455 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 456 return (false); 457} 458 459/* 460 * Ethernet link layer output routine to send a raw frame to the device. 461 * 462 * This assumes that the 14 byte Ethernet header is present and contiguous 463 * in the first mbuf (if BRIDGE'ing). 464 */ 465int 466ether_output_frame(struct ifnet *ifp, struct mbuf *m) 467{ 468 int error; 469 uint8_t pcp; 470 471 pcp = ifp->if_pcp; 472 if (pcp != IFNET_PCP_NONE && !ether_set_pcp(&m, ifp, pcp)) 473 return (0); 474 475 if (PFIL_HOOKED(&V_link_pfil_hook)) { 476 error = pfil_run_hooks(&V_link_pfil_hook, &m, ifp, 477 PFIL_OUT, 0, NULL); 478 if (error != 0) 479 return (EACCES); 480 481 if (m == NULL) 482 return (0); 483 } 484 485 /* 486 * Queue message on interface, update output statistics if 487 * successful, and start output if interface not yet active. 488 */ 489 return ((ifp->if_transmit)(ifp, m)); 490} 491 492/* 493 * Process a received Ethernet packet; the packet is in the 494 * mbuf chain m with the ethernet header at the front. 495 */ 496static void 497ether_input_internal(struct ifnet *ifp, struct mbuf *m) 498{ 499 struct ether_header *eh; 500 u_short etype; 501 502 if ((ifp->if_flags & IFF_UP) == 0) { 503 m_freem(m); 504 return; 505 } 506#ifdef DIAGNOSTIC 507 if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0) { 508 if_printf(ifp, "discard frame at !IFF_DRV_RUNNING\n"); 509 m_freem(m); 510 return; 511 } 512#endif 513 if (m->m_len < ETHER_HDR_LEN) { 514 /* XXX maybe should pullup? */ 515 if_printf(ifp, "discard frame w/o leading ethernet " 516 "header (len %u pkt len %u)\n", 517 m->m_len, m->m_pkthdr.len); 518 if_inc_counter(ifp, IFCOUNTER_IERRORS, 1); 519 m_freem(m); 520 return; 521 } 522 eh = mtod(m, struct ether_header *); 523 etype = ntohs(eh->ether_type); 524 random_harvest_queue(m, sizeof(*m), 2, RANDOM_NET_ETHER); 525 526 CURVNET_SET_QUIET(ifp->if_vnet); 527 528 if (ETHER_IS_MULTICAST(eh->ether_dhost)) { 529 if (ETHER_IS_BROADCAST(eh->ether_dhost)) 530 m->m_flags |= M_BCAST; 531 else 532 m->m_flags |= M_MCAST; 533 if_inc_counter(ifp, IFCOUNTER_IMCASTS, 1); 534 } 535 536#ifdef MAC 537 /* 538 * Tag the mbuf with an appropriate MAC label before any other 539 * consumers can get to it. 540 */ 541 mac_ifnet_create_mbuf(ifp, m); 542#endif 543 544 /* 545 * Give bpf a chance at the packet. 546 */ 547 ETHER_BPF_MTAP(ifp, m); 548 549 /* 550 * If the CRC is still on the packet, trim it off. We do this once 551 * and once only in case we are re-entered. Nothing else on the 552 * Ethernet receive path expects to see the FCS. 553 */ 554 if (m->m_flags & M_HASFCS) { 555 m_adj(m, -ETHER_CRC_LEN); 556 m->m_flags &= ~M_HASFCS; 557 } 558 559 if (!(ifp->if_capenable & IFCAP_HWSTATS)) 560 if_inc_counter(ifp, IFCOUNTER_IBYTES, m->m_pkthdr.len); 561 562 /* Allow monitor mode to claim this frame, after stats are updated. */ 563 if (ifp->if_flags & IFF_MONITOR) { 564 m_freem(m); 565 CURVNET_RESTORE(); 566 return; 567 } 568 569 /* Handle input from a lagg(4) port */ 570 if (ifp->if_type == IFT_IEEE8023ADLAG) { 571 KASSERT(lagg_input_p != NULL, 572 ("%s: if_lagg not loaded!", __func__)); 573 m = (*lagg_input_p)(ifp, m); 574 if (m != NULL) 575 ifp = m->m_pkthdr.rcvif; 576 else { 577 CURVNET_RESTORE(); 578 return; 579 } 580 } 581 582 /* 583 * If the hardware did not process an 802.1Q tag, do this now, 584 * to allow 802.1P priority frames to be passed to the main input 585 * path correctly. 586 * TODO: Deal with Q-in-Q frames, but not arbitrary nesting levels. 587 */ 588 if ((m->m_flags & M_VLANTAG) == 0 && etype == ETHERTYPE_VLAN) { 589 struct ether_vlan_header *evl; 590 591 if (m->m_len < sizeof(*evl) && 592 (m = m_pullup(m, sizeof(*evl))) == NULL) { 593#ifdef DIAGNOSTIC 594 if_printf(ifp, "cannot pullup VLAN header\n"); 595#endif 596 if_inc_counter(ifp, IFCOUNTER_IERRORS, 1); 597 CURVNET_RESTORE(); 598 return; 599 } 600 601 evl = mtod(m, struct ether_vlan_header *); 602 m->m_pkthdr.ether_vtag = ntohs(evl->evl_tag); 603 m->m_flags |= M_VLANTAG; 604 605 bcopy((char *)evl, (char *)evl + ETHER_VLAN_ENCAP_LEN, 606 ETHER_HDR_LEN - ETHER_TYPE_LEN); 607 m_adj(m, ETHER_VLAN_ENCAP_LEN); 608 eh = mtod(m, struct ether_header *); 609 } 610 611 M_SETFIB(m, ifp->if_fib); 612 613 /* Allow ng_ether(4) to claim this frame. */ 614 if (ifp->if_l2com != NULL) { 615 KASSERT(ng_ether_input_p != NULL, 616 ("%s: ng_ether_input_p is NULL", __func__)); 617 m->m_flags &= ~M_PROMISC; 618 (*ng_ether_input_p)(ifp, &m); 619 if (m == NULL) { 620 CURVNET_RESTORE(); 621 return; 622 } 623 eh = mtod(m, struct ether_header *); 624 } 625 626 /* 627 * Allow if_bridge(4) to claim this frame. 628 * The BRIDGE_INPUT() macro will update ifp if the bridge changed it 629 * and the frame should be delivered locally. 630 */ 631 if (ifp->if_bridge != NULL) { 632 m->m_flags &= ~M_PROMISC; 633 BRIDGE_INPUT(ifp, m); 634 if (m == NULL) { 635 CURVNET_RESTORE(); 636 return; 637 } 638 eh = mtod(m, struct ether_header *); 639 } 640 641#if defined(INET) || defined(INET6) 642 /* 643 * Clear M_PROMISC on frame so that carp(4) will see it when the 644 * mbuf flows up to Layer 3. 645 * FreeBSD's implementation of carp(4) uses the inprotosw 646 * to dispatch IPPROTO_CARP. carp(4) also allocates its own 647 * Ethernet addresses of the form 00:00:5e:00:01:xx, which 648 * is outside the scope of the M_PROMISC test below. 649 * TODO: Maintain a hash table of ethernet addresses other than 650 * ether_dhost which may be active on this ifp. 651 */ 652 if (ifp->if_carp && (*carp_forus_p)(ifp, eh->ether_dhost)) { 653 m->m_flags &= ~M_PROMISC; 654 } else 655#endif 656 { 657 /* 658 * If the frame received was not for our MAC address, set the 659 * M_PROMISC flag on the mbuf chain. The frame may need to 660 * be seen by the rest of the Ethernet input path in case of 661 * re-entry (e.g. bridge, vlan, netgraph) but should not be 662 * seen by upper protocol layers. 663 */ 664 if (!ETHER_IS_MULTICAST(eh->ether_dhost) && 665 bcmp(IF_LLADDR(ifp), eh->ether_dhost, ETHER_ADDR_LEN) != 0) 666 m->m_flags |= M_PROMISC; 667 } 668 669 ether_demux(ifp, m); 670 CURVNET_RESTORE(); 671} 672 673/* 674 * Ethernet input dispatch; by default, direct dispatch here regardless of 675 * global configuration. However, if RSS is enabled, hook up RSS affinity 676 * so that when deferred or hybrid dispatch is enabled, we can redistribute 677 * load based on RSS. 678 * 679 * XXXRW: Would be nice if the ifnet passed up a flag indicating whether or 680 * not it had already done work distribution via multi-queue. Then we could 681 * direct dispatch in the event load balancing was already complete and 682 * handle the case of interfaces with different capabilities better. 683 * 684 * XXXRW: Sort of want an M_DISTRIBUTED flag to avoid multiple distributions 685 * at multiple layers? 686 * 687 * XXXRW: For now, enable all this only if RSS is compiled in, although it 688 * works fine without RSS. Need to characterise the performance overhead 689 * of the detour through the netisr code in the event the result is always 690 * direct dispatch. 691 */ 692static void 693ether_nh_input(struct mbuf *m) 694{ 695 696 M_ASSERTPKTHDR(m); 697 KASSERT(m->m_pkthdr.rcvif != NULL, 698 ("%s: NULL interface pointer", __func__)); 699 ether_input_internal(m->m_pkthdr.rcvif, m); 700} 701 702static struct netisr_handler ether_nh = { 703 .nh_name = "ether", 704 .nh_handler = ether_nh_input, 705 .nh_proto = NETISR_ETHER, 706#ifdef RSS 707 .nh_policy = NETISR_POLICY_CPU, 708 .nh_dispatch = NETISR_DISPATCH_DIRECT, 709 .nh_m2cpuid = rss_m2cpuid, 710#else 711 .nh_policy = NETISR_POLICY_SOURCE, 712 .nh_dispatch = NETISR_DISPATCH_DIRECT, 713#endif 714}; 715 716static void 717ether_init(__unused void *arg) 718{ 719 720 netisr_register(ðer_nh); 721} 722SYSINIT(ether, SI_SUB_INIT_IF, SI_ORDER_ANY, ether_init, NULL); 723 724static void 725vnet_ether_init(__unused void *arg) 726{ 727 int i; 728 729 /* Initialize packet filter hooks. */ 730 V_link_pfil_hook.ph_type = PFIL_TYPE_AF; 731 V_link_pfil_hook.ph_af = AF_LINK; 732 if ((i = pfil_head_register(&V_link_pfil_hook)) != 0) 733 printf("%s: WARNING: unable to register pfil link hook, " 734 "error %d\n", __func__, i); 735#ifdef VIMAGE 736 netisr_register_vnet(ðer_nh); 737#endif 738} 739VNET_SYSINIT(vnet_ether_init, SI_SUB_PROTO_IF, SI_ORDER_ANY, 740 vnet_ether_init, NULL); 741 742#ifdef VIMAGE 743static void 744vnet_ether_pfil_destroy(__unused void *arg) 745{ 746 int i; 747 748 if ((i = pfil_head_unregister(&V_link_pfil_hook)) != 0) 749 printf("%s: WARNING: unable to unregister pfil link hook, " 750 "error %d\n", __func__, i); 751} 752VNET_SYSUNINIT(vnet_ether_pfil_uninit, SI_SUB_PROTO_PFIL, SI_ORDER_ANY, 753 vnet_ether_pfil_destroy, NULL); 754 755static void 756vnet_ether_destroy(__unused void *arg) 757{ 758 759 netisr_unregister_vnet(ðer_nh); 760} 761VNET_SYSUNINIT(vnet_ether_uninit, SI_SUB_PROTO_IF, SI_ORDER_ANY, 762 vnet_ether_destroy, NULL); 763#endif 764 765 766 767static void 768ether_input(struct ifnet *ifp, struct mbuf *m) 769{ 770 771 struct mbuf *mn; 772 773 /* 774 * The drivers are allowed to pass in a chain of packets linked with 775 * m_nextpkt. We split them up into separate packets here and pass 776 * them up. This allows the drivers to amortize the receive lock. 777 */ 778 while (m) { 779 mn = m->m_nextpkt; 780 m->m_nextpkt = NULL; 781 782 /* 783 * We will rely on rcvif being set properly in the deferred context, 784 * so assert it is correct here. 785 */ 786 KASSERT(m->m_pkthdr.rcvif == ifp, ("%s: ifnet mismatch m %p " 787 "rcvif %p ifp %p", __func__, m, m->m_pkthdr.rcvif, ifp)); 788 CURVNET_SET_QUIET(ifp->if_vnet); 789 netisr_dispatch(NETISR_ETHER, m); 790 CURVNET_RESTORE(); 791 m = mn; 792 } 793} 794 795/* 796 * Upper layer processing for a received Ethernet packet. 797 */ 798void 799ether_demux(struct ifnet *ifp, struct mbuf *m) 800{ 801 struct ether_header *eh; 802 int i, isr; 803 u_short ether_type; 804 805 KASSERT(ifp != NULL, ("%s: NULL interface pointer", __func__)); 806 807 /* Do not grab PROMISC frames in case we are re-entered. */ 808 if (PFIL_HOOKED(&V_link_pfil_hook) && !(m->m_flags & M_PROMISC)) { 809 i = pfil_run_hooks(&V_link_pfil_hook, &m, ifp, PFIL_IN, 0, 810 NULL); 811 812 if (i != 0 || m == NULL) 813 return; 814 } 815 816 eh = mtod(m, struct ether_header *); 817 ether_type = ntohs(eh->ether_type); 818 819 /* 820 * If this frame has a VLAN tag other than 0, call vlan_input() 821 * if its module is loaded. Otherwise, drop. 822 */ 823 if ((m->m_flags & M_VLANTAG) && 824 EVL_VLANOFTAG(m->m_pkthdr.ether_vtag) != 0) { 825 if (ifp->if_vlantrunk == NULL) { 826 if_inc_counter(ifp, IFCOUNTER_NOPROTO, 1); 827 m_freem(m); 828 return; 829 } 830 KASSERT(vlan_input_p != NULL,("%s: VLAN not loaded!", 831 __func__)); 832 /* Clear before possibly re-entering ether_input(). */ 833 m->m_flags &= ~M_PROMISC; 834 (*vlan_input_p)(ifp, m); 835 return; 836 } 837 838 /* 839 * Pass promiscuously received frames to the upper layer if the user 840 * requested this by setting IFF_PPROMISC. Otherwise, drop them. 841 */ 842 if ((ifp->if_flags & IFF_PPROMISC) == 0 && (m->m_flags & M_PROMISC)) { 843 m_freem(m); 844 return; 845 } 846 847 /* 848 * Reset layer specific mbuf flags to avoid confusing upper layers. 849 * Strip off Ethernet header. 850 */ 851 m->m_flags &= ~M_VLANTAG; 852 m_clrprotoflags(m); 853 m_adj(m, ETHER_HDR_LEN); 854 855 /* 856 * Dispatch frame to upper layer. 857 */ 858 switch (ether_type) { 859#ifdef INET 860 case ETHERTYPE_IP: 861 isr = NETISR_IP; 862 break; 863 864 case ETHERTYPE_ARP: 865 if (ifp->if_flags & IFF_NOARP) { 866 /* Discard packet if ARP is disabled on interface */ 867 m_freem(m); 868 return; 869 } 870 isr = NETISR_ARP; 871 break; 872#endif 873#ifdef INET6 874 case ETHERTYPE_IPV6: 875 isr = NETISR_IPV6; 876 break; 877#endif 878 default: 879 goto discard; 880 } 881 netisr_dispatch(isr, m); 882 return; 883 884discard: 885 /* 886 * Packet is to be discarded. If netgraph is present, 887 * hand the packet to it for last chance processing; 888 * otherwise dispose of it. 889 */ 890 if (ifp->if_l2com != NULL) { 891 KASSERT(ng_ether_input_orphan_p != NULL, 892 ("ng_ether_input_orphan_p is NULL")); 893 /* 894 * Put back the ethernet header so netgraph has a 895 * consistent view of inbound packets. 896 */ 897 M_PREPEND(m, ETHER_HDR_LEN, M_NOWAIT); 898 (*ng_ether_input_orphan_p)(ifp, m); 899 return; 900 } 901 m_freem(m); 902} 903 904/* 905 * Convert Ethernet address to printable (loggable) representation. 906 * This routine is for compatibility; it's better to just use 907 * 908 * printf("%6D", <pointer to address>, ":"); 909 * 910 * since there's no static buffer involved. 911 */ 912char * 913ether_sprintf(const u_char *ap) 914{ 915 static char etherbuf[18]; 916 snprintf(etherbuf, sizeof (etherbuf), "%6D", ap, ":"); 917 return (etherbuf); 918} 919 920/* 921 * Perform common duties while attaching to interface list 922 */ 923void 924ether_ifattach(struct ifnet *ifp, const u_int8_t *lla) 925{ 926 int i; 927 struct ifaddr *ifa; 928 struct sockaddr_dl *sdl; 929 930 ifp->if_addrlen = ETHER_ADDR_LEN; 931 ifp->if_hdrlen = ETHER_HDR_LEN; 932 if_attach(ifp); 933 ifp->if_mtu = ETHERMTU; 934 ifp->if_output = ether_output; 935 ifp->if_input = ether_input; 936 ifp->if_resolvemulti = ether_resolvemulti; 937 ifp->if_requestencap = ether_requestencap; 938#ifdef VIMAGE 939 ifp->if_reassign = ether_reassign; 940#endif 941 if (ifp->if_baudrate == 0) 942 ifp->if_baudrate = IF_Mbps(10); /* just a default */ 943 ifp->if_broadcastaddr = etherbroadcastaddr; 944 945 ifa = ifp->if_addr; 946 KASSERT(ifa != NULL, ("%s: no lladdr!\n", __func__)); 947 sdl = (struct sockaddr_dl *)ifa->ifa_addr; 948 sdl->sdl_type = IFT_ETHER; 949 sdl->sdl_alen = ifp->if_addrlen; 950 bcopy(lla, LLADDR(sdl), ifp->if_addrlen); 951 952 if (ifp->if_hw_addr != NULL) 953 bcopy(lla, ifp->if_hw_addr, ifp->if_addrlen); 954 955 bpfattach(ifp, DLT_EN10MB, ETHER_HDR_LEN); 956 if (ng_ether_attach_p != NULL) 957 (*ng_ether_attach_p)(ifp); 958 959 /* Announce Ethernet MAC address if non-zero. */ 960 for (i = 0; i < ifp->if_addrlen; i++) 961 if (lla[i] != 0) 962 break; 963 if (i != ifp->if_addrlen) 964 if_printf(ifp, "Ethernet address: %6D\n", lla, ":"); 965 966 uuid_ether_add(LLADDR(sdl)); 967 968 /* Add necessary bits are setup; announce it now. */ 969 EVENTHANDLER_INVOKE(ether_ifattach_event, ifp); 970 if (IS_DEFAULT_VNET(curvnet)) 971 devctl_notify("ETHERNET", ifp->if_xname, "IFATTACH", NULL); 972} 973 974/* 975 * Perform common duties while detaching an Ethernet interface 976 */ 977void 978ether_ifdetach(struct ifnet *ifp) 979{ 980 struct sockaddr_dl *sdl; 981 982 sdl = (struct sockaddr_dl *)(ifp->if_addr->ifa_addr); 983 uuid_ether_del(LLADDR(sdl)); 984 985 if (ifp->if_l2com != NULL) { 986 KASSERT(ng_ether_detach_p != NULL, 987 ("ng_ether_detach_p is NULL")); 988 (*ng_ether_detach_p)(ifp); 989 } 990 991 bpfdetach(ifp); 992 if_detach(ifp); 993} 994 995#ifdef VIMAGE 996void 997ether_reassign(struct ifnet *ifp, struct vnet *new_vnet, char *unused __unused) 998{ 999 1000 if (ifp->if_l2com != NULL) { 1001 KASSERT(ng_ether_detach_p != NULL, 1002 ("ng_ether_detach_p is NULL")); 1003 (*ng_ether_detach_p)(ifp); 1004 } 1005 1006 if (ng_ether_attach_p != NULL) { 1007 CURVNET_SET_QUIET(new_vnet); 1008 (*ng_ether_attach_p)(ifp); 1009 CURVNET_RESTORE(); 1010 } 1011} 1012#endif 1013 1014SYSCTL_DECL(_net_link); 1015SYSCTL_NODE(_net_link, IFT_ETHER, ether, CTLFLAG_RW, 0, "Ethernet"); 1016 1017#if 0 1018/* 1019 * This is for reference. We have a table-driven version 1020 * of the little-endian crc32 generator, which is faster 1021 * than the double-loop. 1022 */ 1023uint32_t 1024ether_crc32_le(const uint8_t *buf, size_t len) 1025{ 1026 size_t i; 1027 uint32_t crc; 1028 int bit; 1029 uint8_t data; 1030 1031 crc = 0xffffffff; /* initial value */ 1032 1033 for (i = 0; i < len; i++) { 1034 for (data = *buf++, bit = 0; bit < 8; bit++, data >>= 1) { 1035 carry = (crc ^ data) & 1; 1036 crc >>= 1; 1037 if (carry) 1038 crc = (crc ^ ETHER_CRC_POLY_LE); 1039 } 1040 } 1041 1042 return (crc); 1043} 1044#else 1045uint32_t 1046ether_crc32_le(const uint8_t *buf, size_t len) 1047{ 1048 static const uint32_t crctab[] = { 1049 0x00000000, 0x1db71064, 0x3b6e20c8, 0x26d930ac, 1050 0x76dc4190, 0x6b6b51f4, 0x4db26158, 0x5005713c, 1051 0xedb88320, 0xf00f9344, 0xd6d6a3e8, 0xcb61b38c, 1052 0x9b64c2b0, 0x86d3d2d4, 0xa00ae278, 0xbdbdf21c 1053 }; 1054 size_t i; 1055 uint32_t crc; 1056 1057 crc = 0xffffffff; /* initial value */ 1058 1059 for (i = 0; i < len; i++) { 1060 crc ^= buf[i]; 1061 crc = (crc >> 4) ^ crctab[crc & 0xf]; 1062 crc = (crc >> 4) ^ crctab[crc & 0xf]; 1063 } 1064 1065 return (crc); 1066} 1067#endif 1068 1069uint32_t 1070ether_crc32_be(const uint8_t *buf, size_t len) 1071{ 1072 size_t i; 1073 uint32_t crc, carry; 1074 int bit; 1075 uint8_t data; 1076 1077 crc = 0xffffffff; /* initial value */ 1078 1079 for (i = 0; i < len; i++) { 1080 for (data = *buf++, bit = 0; bit < 8; bit++, data >>= 1) { 1081 carry = ((crc & 0x80000000) ? 1 : 0) ^ (data & 0x01); 1082 crc <<= 1; 1083 if (carry) 1084 crc = (crc ^ ETHER_CRC_POLY_BE) | carry; 1085 } 1086 } 1087 1088 return (crc); 1089} 1090 1091int 1092ether_ioctl(struct ifnet *ifp, u_long command, caddr_t data) 1093{ 1094 struct ifaddr *ifa = (struct ifaddr *) data; 1095 struct ifreq *ifr = (struct ifreq *) data; 1096 int error = 0; 1097 1098 switch (command) { 1099 case SIOCSIFADDR: 1100 ifp->if_flags |= IFF_UP; 1101 1102 switch (ifa->ifa_addr->sa_family) { 1103#ifdef INET 1104 case AF_INET: 1105 ifp->if_init(ifp->if_softc); /* before arpwhohas */ 1106 arp_ifinit(ifp, ifa); 1107 break; 1108#endif 1109 default: 1110 ifp->if_init(ifp->if_softc); 1111 break; 1112 } 1113 break; 1114 1115 case SIOCGIFADDR: 1116 bcopy(IF_LLADDR(ifp), &ifr->ifr_addr.sa_data[0], 1117 ETHER_ADDR_LEN); 1118 break; 1119 1120 case SIOCSIFMTU: 1121 /* 1122 * Set the interface MTU. 1123 */ 1124 if (ifr->ifr_mtu > ETHERMTU) { 1125 error = EINVAL; 1126 } else { 1127 ifp->if_mtu = ifr->ifr_mtu; 1128 } 1129 break; 1130 1131 case SIOCSLANPCP: 1132 error = priv_check(curthread, PRIV_NET_SETLANPCP); 1133 if (error != 0) 1134 break; 1135 if (ifr->ifr_lan_pcp > 7 && 1136 ifr->ifr_lan_pcp != IFNET_PCP_NONE) { 1137 error = EINVAL; 1138 } else { 1139 ifp->if_pcp = ifr->ifr_lan_pcp; 1140 /* broadcast event about PCP change */ 1141 EVENTHANDLER_INVOKE(ifnet_event, ifp, IFNET_EVENT_PCP); 1142 } 1143 break; 1144 1145 case SIOCGLANPCP: 1146 ifr->ifr_lan_pcp = ifp->if_pcp; 1147 break; 1148 1149 default: 1150 error = EINVAL; /* XXX netbsd has ENOTTY??? */ 1151 break; 1152 } 1153 return (error); 1154} 1155 1156static int 1157ether_resolvemulti(struct ifnet *ifp, struct sockaddr **llsa, 1158 struct sockaddr *sa) 1159{ 1160 struct sockaddr_dl *sdl; 1161#ifdef INET 1162 struct sockaddr_in *sin; 1163#endif 1164#ifdef INET6 1165 struct sockaddr_in6 *sin6; 1166#endif 1167 u_char *e_addr; 1168 1169 switch(sa->sa_family) { 1170 case AF_LINK: 1171 /* 1172 * No mapping needed. Just check that it's a valid MC address. 1173 */ 1174 sdl = (struct sockaddr_dl *)sa; 1175 e_addr = LLADDR(sdl); 1176 if (!ETHER_IS_MULTICAST(e_addr)) 1177 return EADDRNOTAVAIL; 1178 *llsa = NULL; 1179 return 0; 1180 1181#ifdef INET 1182 case AF_INET: 1183 sin = (struct sockaddr_in *)sa; 1184 if (!IN_MULTICAST(ntohl(sin->sin_addr.s_addr))) 1185 return EADDRNOTAVAIL; 1186 sdl = link_init_sdl(ifp, *llsa, IFT_ETHER); 1187 sdl->sdl_alen = ETHER_ADDR_LEN; 1188 e_addr = LLADDR(sdl); 1189 ETHER_MAP_IP_MULTICAST(&sin->sin_addr, e_addr); 1190 *llsa = (struct sockaddr *)sdl; 1191 return 0; 1192#endif 1193#ifdef INET6 1194 case AF_INET6: 1195 sin6 = (struct sockaddr_in6 *)sa; 1196 if (IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr)) { 1197 /* 1198 * An IP6 address of 0 means listen to all 1199 * of the Ethernet multicast address used for IP6. 1200 * (This is used for multicast routers.) 1201 */ 1202 ifp->if_flags |= IFF_ALLMULTI; 1203 *llsa = NULL; 1204 return 0; 1205 } 1206 if (!IN6_IS_ADDR_MULTICAST(&sin6->sin6_addr)) 1207 return EADDRNOTAVAIL; 1208 sdl = link_init_sdl(ifp, *llsa, IFT_ETHER); 1209 sdl->sdl_alen = ETHER_ADDR_LEN; 1210 e_addr = LLADDR(sdl); 1211 ETHER_MAP_IPV6_MULTICAST(&sin6->sin6_addr, e_addr); 1212 *llsa = (struct sockaddr *)sdl; 1213 return 0; 1214#endif 1215 1216 default: 1217 /* 1218 * Well, the text isn't quite right, but it's the name 1219 * that counts... 1220 */ 1221 return EAFNOSUPPORT; 1222 } 1223} 1224 1225static moduledata_t ether_mod = { 1226 .name = "ether", 1227}; 1228 1229void 1230ether_vlan_mtap(struct bpf_if *bp, struct mbuf *m, void *data, u_int dlen) 1231{ 1232 struct ether_vlan_header vlan; 1233 struct mbuf mv, mb; 1234 1235 KASSERT((m->m_flags & M_VLANTAG) != 0, 1236 ("%s: vlan information not present", __func__)); 1237 KASSERT(m->m_len >= sizeof(struct ether_header), 1238 ("%s: mbuf not large enough for header", __func__)); 1239 bcopy(mtod(m, char *), &vlan, sizeof(struct ether_header)); 1240 vlan.evl_proto = vlan.evl_encap_proto; 1241 vlan.evl_encap_proto = htons(ETHERTYPE_VLAN); 1242 vlan.evl_tag = htons(m->m_pkthdr.ether_vtag); 1243 m->m_len -= sizeof(struct ether_header); 1244 m->m_data += sizeof(struct ether_header); 1245 /* 1246 * If a data link has been supplied by the caller, then we will need to 1247 * re-create a stack allocated mbuf chain with the following structure: 1248 * 1249 * (1) mbuf #1 will contain the supplied data link 1250 * (2) mbuf #2 will contain the vlan header 1251 * (3) mbuf #3 will contain the original mbuf's packet data 1252 * 1253 * Otherwise, submit the packet and vlan header via bpf_mtap2(). 1254 */ 1255 if (data != NULL) { 1256 mv.m_next = m; 1257 mv.m_data = (caddr_t)&vlan; 1258 mv.m_len = sizeof(vlan); 1259 mb.m_next = &mv; 1260 mb.m_data = data; 1261 mb.m_len = dlen; 1262 bpf_mtap(bp, &mb); 1263 } else 1264 bpf_mtap2(bp, &vlan, sizeof(vlan), m); 1265 m->m_len += sizeof(struct ether_header); 1266 m->m_data -= sizeof(struct ether_header); 1267} 1268 1269struct mbuf * 1270ether_vlanencap(struct mbuf *m, uint16_t tag) 1271{ 1272 struct ether_vlan_header *evl; 1273 1274 M_PREPEND(m, ETHER_VLAN_ENCAP_LEN, M_NOWAIT); 1275 if (m == NULL) 1276 return (NULL); 1277 /* M_PREPEND takes care of m_len, m_pkthdr.len for us */ 1278 1279 if (m->m_len < sizeof(*evl)) { 1280 m = m_pullup(m, sizeof(*evl)); 1281 if (m == NULL) 1282 return (NULL); 1283 } 1284 1285 /* 1286 * Transform the Ethernet header into an Ethernet header 1287 * with 802.1Q encapsulation. 1288 */ 1289 evl = mtod(m, struct ether_vlan_header *); 1290 bcopy((char *)evl + ETHER_VLAN_ENCAP_LEN, 1291 (char *)evl, ETHER_HDR_LEN - ETHER_TYPE_LEN); 1292 evl->evl_encap_proto = htons(ETHERTYPE_VLAN); 1293 evl->evl_tag = htons(tag); 1294 return (m); 1295} 1296 1297static SYSCTL_NODE(_net_link, IFT_L2VLAN, vlan, CTLFLAG_RW, 0, 1298 "IEEE 802.1Q VLAN"); 1299static SYSCTL_NODE(_net_link_vlan, PF_LINK, link, CTLFLAG_RW, 0, 1300 "for consistency"); 1301 1302static VNET_DEFINE(int, soft_pad); 1303#define V_soft_pad VNET(soft_pad) 1304SYSCTL_INT(_net_link_vlan, OID_AUTO, soft_pad, CTLFLAG_RW | CTLFLAG_VNET, 1305 &VNET_NAME(soft_pad), 0, 1306 "pad short frames before tagging"); 1307 1308/* 1309 * For now, make preserving PCP via an mbuf tag optional, as it increases 1310 * per-packet memory allocations and frees. In the future, it would be 1311 * preferable to reuse ether_vtag for this, or similar. 1312 */ 1313int vlan_mtag_pcp = 0; 1314SYSCTL_INT(_net_link_vlan, OID_AUTO, mtag_pcp, CTLFLAG_RW, 1315 &vlan_mtag_pcp, 0, 1316 "Retain VLAN PCP information as packets are passed up the stack"); 1317 1318bool 1319ether_8021q_frame(struct mbuf **mp, struct ifnet *ife, struct ifnet *p, 1320 uint16_t vid, uint8_t pcp) 1321{ 1322 struct m_tag *mtag; 1323 int n; 1324 uint16_t tag; 1325 static const char pad[8]; /* just zeros */ 1326 1327 /* 1328 * Pad the frame to the minimum size allowed if told to. 1329 * This option is in accord with IEEE Std 802.1Q, 2003 Ed., 1330 * paragraph C.4.4.3.b. It can help to work around buggy 1331 * bridges that violate paragraph C.4.4.3.a from the same 1332 * document, i.e., fail to pad short frames after untagging. 1333 * E.g., a tagged frame 66 bytes long (incl. FCS) is OK, but 1334 * untagging it will produce a 62-byte frame, which is a runt 1335 * and requires padding. There are VLAN-enabled network 1336 * devices that just discard such runts instead or mishandle 1337 * them somehow. 1338 */ 1339 if (V_soft_pad && p->if_type == IFT_ETHER) { 1340 for (n = ETHERMIN + ETHER_HDR_LEN - (*mp)->m_pkthdr.len; 1341 n > 0; n -= sizeof(pad)) { 1342 if (!m_append(*mp, min(n, sizeof(pad)), pad)) 1343 break; 1344 } 1345 if (n > 0) { 1346 m_freem(*mp); 1347 *mp = NULL; 1348 if_printf(ife, "cannot pad short frame"); 1349 return (false); 1350 } 1351 } 1352 1353 /* 1354 * If underlying interface can do VLAN tag insertion itself, 1355 * just pass the packet along. However, we need some way to 1356 * tell the interface where the packet came from so that it 1357 * knows how to find the VLAN tag to use, so we attach a 1358 * packet tag that holds it. 1359 */ 1360 if (vlan_mtag_pcp && (mtag = m_tag_locate(*mp, MTAG_8021Q, 1361 MTAG_8021Q_PCP_OUT, NULL)) != NULL) 1362 tag = EVL_MAKETAG(vid, *(uint8_t *)(mtag + 1), 0); 1363 else 1364 tag = EVL_MAKETAG(vid, pcp, 0); 1365 if (p->if_capenable & IFCAP_VLAN_HWTAGGING) { 1366 (*mp)->m_pkthdr.ether_vtag = tag; 1367 (*mp)->m_flags |= M_VLANTAG; 1368 } else { 1369 *mp = ether_vlanencap(*mp, tag); 1370 if (*mp == NULL) { 1371 if_printf(ife, "unable to prepend 802.1Q header"); 1372 return (false); 1373 } 1374 } 1375 return (true); 1376} 1377 1378/* 1379 * Allocate an address from the FreeBSD Foundation OUI. This uses a 1380 * cryptographic hash function on the containing jail's name, UUID and the 1381 * interface name to attempt to provide a unique but stable address. 1382 * Pseudo-interfaces which require a MAC address should use this function to 1383 * allocate non-locally-administered addresses. 1384 */ 1385void 1386ether_gen_addr(struct ifnet *ifp, struct ether_addr *hwaddr) 1387{ 1388 SHA1_CTX ctx; 1389 char *buf; 1390 char uuid[HOSTUUIDLEN + 1]; 1391 uint64_t addr; 1392 int i, sz; 1393 char digest[SHA1_RESULTLEN]; 1394 char jailname[MAXHOSTNAMELEN]; 1395 1396 getcredhostuuid(curthread->td_ucred, uuid, sizeof(uuid)); 1397 /* If each (vnet) jail would also have a unique hostuuid this would not 1398 * be necessary. */ 1399 getjailname(curthread->td_ucred, jailname, sizeof(jailname)); 1400 sz = asprintf(&buf, M_TEMP, "%s-%s-%s", uuid, if_name(ifp), 1401 jailname); 1402 if (sz < 0) { 1403 /* Fall back to a random mac address. */ 1404 arc4rand(hwaddr, sizeof(*hwaddr), 0); 1405 hwaddr->octet[0] = 0x02; 1406 return; 1407 } 1408 1409 SHA1Init(&ctx); 1410 SHA1Update(&ctx, buf, sz); 1411 SHA1Final(digest, &ctx); 1412 free(buf, M_TEMP); 1413 1414 addr = ((digest[0] << 16) | (digest[1] << 8) | digest[2]) & 1415 OUI_FREEBSD_GENERATED_MASK; 1416 addr = OUI_FREEBSD(addr); 1417 for (i = 0; i < ETHER_ADDR_LEN; ++i) { 1418 hwaddr->octet[i] = addr >> ((ETHER_ADDR_LEN - i - 1) * 8) & 1419 0xFF; 1420 } 1421} 1422 1423DECLARE_MODULE(ether, ether_mod, SI_SUB_INIT_IF, SI_ORDER_ANY); 1424MODULE_VERSION(ether, 1); 1425