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sys/net/if_ethersubr.c
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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: releng/11.0/sys/net/if_ethersubr.c 301498 2016-06-06 10:13:48Z bz $ 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/kernel.h> 42 #include <sys/lock.h> 43 #include <sys/malloc.h> 44 #include <sys/module.h> 45 #include <sys/mbuf.h> 46 #include <sys/random.h> 47 #include <sys/socket.h> 48 #include <sys/sockio.h> 49 #include <sys/sysctl.h> 50 #include <sys/uuid.h> 51 52 #include <net/if.h> 53 #include <net/if_var.h> 54 #include <net/if_arp.h> 55 #include <net/netisr.h> 56 #include <net/route.h> 57 #include <net/if_llc.h> 58 #include <net/if_dl.h> 59 #include <net/if_types.h> 60 #include <net/bpf.h> 61 #include <net/ethernet.h> 62 #include <net/if_bridgevar.h> 63 #include <net/if_vlan_var.h> 64 #include <net/if_llatbl.h> 65 #include <net/pfil.h> 66 #include <net/rss_config.h> 67 #include <net/vnet.h> 68 69 #include <netpfil/pf/pf_mtag.h> 70 71 #if defined(INET) || defined(INET6) 72 #include <netinet/in.h> 73 #include <netinet/in_var.h> 74 #include <netinet/if_ether.h> 75 #include <netinet/ip_carp.h> 76 #include <netinet/ip_var.h> 77 #endif 78 #ifdef INET6 79 #include <netinet6/nd6.h> 80 #endif 81 #include <security/mac/mac_framework.h> 82 83 #ifdef CTASSERT 84 CTASSERT(sizeof (struct ether_header) == ETHER_ADDR_LEN * 2 + 2); 85 CTASSERT(sizeof (struct ether_addr) == ETHER_ADDR_LEN); 86 #endif 87 88 VNET_DEFINE(struct pfil_head, link_pfil_hook); /* Packet filter hooks */ 89 90 /* netgraph node hooks for ng_ether(4) */ 91 void (*ng_ether_input_p)(struct ifnet *ifp, struct mbuf **mp); 92 void (*ng_ether_input_orphan_p)(struct ifnet *ifp, struct mbuf *m); 93 int (*ng_ether_output_p)(struct ifnet *ifp, struct mbuf **mp); 94 void (*ng_ether_attach_p)(struct ifnet *ifp); 95 void (*ng_ether_detach_p)(struct ifnet *ifp); 96 97 void (*vlan_input_p)(struct ifnet *, struct mbuf *); 98 99 /* if_bridge(4) support */ 100 struct mbuf *(*bridge_input_p)(struct ifnet *, struct mbuf *); 101 int (*bridge_output_p)(struct ifnet *, struct mbuf *, 102 struct sockaddr *, struct rtentry *); 103 void (*bridge_dn_p)(struct mbuf *, struct ifnet *); 104 105 /* if_lagg(4) support */ 106 struct mbuf *(*lagg_input_p)(struct ifnet *, struct mbuf *); 107 108 static const u_char etherbroadcastaddr[ETHER_ADDR_LEN] = 109 { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff }; 110 111 static int ether_resolvemulti(struct ifnet *, struct sockaddr **, 112 struct sockaddr *); 113 #ifdef VIMAGE 114 static void ether_reassign(struct ifnet *, struct vnet *, char *); 115 #endif 116 static int ether_requestencap(struct ifnet *, struct if_encap_req *); 117 118 #define ETHER_IS_BROADCAST(addr) \ 119 (bcmp(etherbroadcastaddr, (addr), ETHER_ADDR_LEN) == 0) 120 121 #define senderr(e) do { error = (e); goto bad;} while (0) 122 123 static void 124 update_mbuf_csumflags(struct mbuf *src, struct mbuf *dst) 125 { 126 int csum_flags = 0; 127 128 if (src->m_pkthdr.csum_flags & CSUM_IP) 129 csum_flags |= (CSUM_IP_CHECKED|CSUM_IP_VALID); 130 if (src->m_pkthdr.csum_flags & CSUM_DELAY_DATA) 131 csum_flags |= (CSUM_DATA_VALID|CSUM_PSEUDO_HDR); 132 if (src->m_pkthdr.csum_flags & CSUM_SCTP) 133 csum_flags |= CSUM_SCTP_VALID; 134 dst->m_pkthdr.csum_flags |= csum_flags; 135 if (csum_flags & CSUM_DATA_VALID) 136 dst->m_pkthdr.csum_data = 0xffff; 137 } 138 139 /* 140 * Handle link-layer encapsulation requests. 141 */ 142 static int 143 ether_requestencap(struct ifnet *ifp, struct if_encap_req *req) 144 { 145 struct ether_header *eh; 146 struct arphdr *ah; 147 uint16_t etype; 148 const u_char *lladdr; 149 150 if (req->rtype != IFENCAP_LL) 151 return (EOPNOTSUPP); 152 153 if (req->bufsize < ETHER_HDR_LEN) 154 return (ENOMEM); 155 156 eh = (struct ether_header *)req->buf; 157 lladdr = req->lladdr; 158 req->lladdr_off = 0; 159 160 switch (req->family) { 161 case AF_INET: 162 etype = htons(ETHERTYPE_IP); 163 break; 164 case AF_INET6: 165 etype = htons(ETHERTYPE_IPV6); 166 break; 167 case AF_ARP: 168 ah = (struct arphdr *)req->hdata; 169 ah->ar_hrd = htons(ARPHRD_ETHER); 170 171 switch(ntohs(ah->ar_op)) { 172 case ARPOP_REVREQUEST: 173 case ARPOP_REVREPLY: 174 etype = htons(ETHERTYPE_REVARP); 175 break; 176 case ARPOP_REQUEST: 177 case ARPOP_REPLY: 178 default: 179 etype = htons(ETHERTYPE_ARP); 180 break; 181 } 182 183 if (req->flags & IFENCAP_FLAG_BROADCAST) 184 lladdr = ifp->if_broadcastaddr; 185 break; 186 default: 187 return (EAFNOSUPPORT); 188 } 189 190 memcpy(&eh->ether_type, &etype, sizeof(eh->ether_type)); 191 memcpy(eh->ether_dhost, lladdr, ETHER_ADDR_LEN); 192 memcpy(eh->ether_shost, IF_LLADDR(ifp), ETHER_ADDR_LEN); 193 req->bufsize = sizeof(struct ether_header); 194 195 return (0); 196 } 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 int loop_copy = 1; 288 int hlen; /* link layer header length */ 289 uint32_t pflags; 290 struct llentry *lle = NULL; 291 struct rtentry *rt0 = NULL; 292 int addref = 0; 293 294 phdr = NULL; 295 pflags = 0; 296 if (ro != NULL) { 297 /* XXX BPF uses ro_prepend */ 298 if (ro->ro_prepend != NULL) { 299 phdr = ro->ro_prepend; 300 hlen = ro->ro_plen; 301 } else if (!(m->m_flags & (M_BCAST | M_MCAST))) { 302 if ((ro->ro_flags & RT_LLE_CACHE) != 0) { 303 lle = ro->ro_lle; 304 if (lle != NULL && 305 (lle->la_flags & LLE_VALID) == 0) { 306 LLE_FREE(lle); 307 lle = NULL; /* redundant */ 308 ro->ro_lle = NULL; 309 } 310 if (lle == NULL) { 311 /* if we lookup, keep cache */ 312 addref = 1; 313 } 314 } 315 if (lle != NULL) { 316 phdr = lle->r_linkdata; 317 hlen = lle->r_hdrlen; 318 pflags = lle->r_flags; 319 } 320 } 321 rt0 = ro->ro_rt; 322 } 323 324 #ifdef MAC 325 error = mac_ifnet_check_transmit(ifp, m); 326 if (error) 327 senderr(error); 328 #endif 329 330 M_PROFILE(m); 331 if (ifp->if_flags & IFF_MONITOR) 332 senderr(ENETDOWN); 333 if (!((ifp->if_flags & IFF_UP) && 334 (ifp->if_drv_flags & IFF_DRV_RUNNING))) 335 senderr(ENETDOWN); 336 337 if (phdr == NULL) { 338 /* No prepend data supplied. Try to calculate ourselves. */ 339 phdr = linkhdr; 340 hlen = ETHER_HDR_LEN; 341 error = ether_resolve_addr(ifp, m, dst, ro, phdr, &pflags, 342 addref ? &lle : NULL); 343 if (addref && lle != NULL) 344 ro->ro_lle = lle; 345 if (error != 0) 346 return (error == EWOULDBLOCK ? 0 : error); 347 } 348 349 if ((pflags & RT_L2_ME) != 0) { 350 update_mbuf_csumflags(m, m); 351 return (if_simloop(ifp, m, dst->sa_family, 0)); 352 } 353 loop_copy = pflags & RT_MAY_LOOP; 354 355 /* 356 * Add local net header. If no space in first mbuf, 357 * allocate another. 358 * 359 * Note that we do prepend regardless of RT_HAS_HEADER flag. 360 * This is done because BPF code shifts m_data pointer 361 * to the end of ethernet header prior to calling if_output(). 362 */ 363 M_PREPEND(m, hlen, M_NOWAIT); 364 if (m == NULL) 365 senderr(ENOBUFS); 366 if ((pflags & RT_HAS_HEADER) == 0) { 367 eh = mtod(m, struct ether_header *); 368 memcpy(eh, phdr, hlen); 369 } 370 371 /* 372 * If a simplex interface, and the packet is being sent to our 373 * Ethernet address or a broadcast address, loopback a copy. 374 * XXX To make a simplex device behave exactly like a duplex 375 * device, we should copy in the case of sending to our own 376 * ethernet address (thus letting the original actually appear 377 * on the wire). However, we don't do that here for security 378 * reasons and compatibility with the original behavior. 379 */ 380 if ((m->m_flags & M_BCAST) && loop_copy && (ifp->if_flags & IFF_SIMPLEX) && 381 ((t = pf_find_mtag(m)) == NULL || !t->routed)) { 382 struct mbuf *n; 383 384 /* 385 * Because if_simloop() modifies the packet, we need a 386 * writable copy through m_dup() instead of a readonly 387 * one as m_copy[m] would give us. The alternative would 388 * be to modify if_simloop() to handle the readonly mbuf, 389 * but performancewise it is mostly equivalent (trading 390 * extra data copying vs. extra locking). 391 * 392 * XXX This is a local workaround. A number of less 393 * often used kernel parts suffer from the same bug. 394 * See PR kern/105943 for a proposed general solution. 395 */ 396 if ((n = m_dup(m, M_NOWAIT)) != NULL) { 397 update_mbuf_csumflags(m, n); 398 (void)if_simloop(ifp, n, dst->sa_family, hlen); 399 } else 400 if_inc_counter(ifp, IFCOUNTER_IQDROPS, 1); 401 } 402 403 /* 404 * Bridges require special output handling. 405 */ 406 if (ifp->if_bridge) { 407 BRIDGE_OUTPUT(ifp, m, error); 408 return (error); 409 } 410 411 #if defined(INET) || defined(INET6) 412 if (ifp->if_carp && 413 (error = (*carp_output_p)(ifp, m, dst))) 414 goto bad; 415 #endif 416 417 /* Handle ng_ether(4) processing, if any */ 418 if (ifp->if_l2com != NULL) { 419 KASSERT(ng_ether_output_p != NULL, 420 ("ng_ether_output_p is NULL")); 421 if ((error = (*ng_ether_output_p)(ifp, &m)) != 0) { 422 bad: if (m != NULL) 423 m_freem(m); 424 return (error); 425 } 426 if (m == NULL) 427 return (0); 428 } 429 430 /* Continue with link-layer output */ 431 return ether_output_frame(ifp, m); 432 } 433 434 /* 435 * Ethernet link layer output routine to send a raw frame to the device. 436 * 437 * This assumes that the 14 byte Ethernet header is present and contiguous 438 * in the first mbuf (if BRIDGE'ing). 439 */ 440 int 441 ether_output_frame(struct ifnet *ifp, struct mbuf *m) 442 { 443 int i; 444 445 if (PFIL_HOOKED(&V_link_pfil_hook)) { 446 i = pfil_run_hooks(&V_link_pfil_hook, &m, ifp, PFIL_OUT, NULL); 447 448 if (i != 0) 449 return (EACCES); 450 451 if (m == NULL) 452 return (0); 453 } 454 455 /* 456 * Queue message on interface, update output statistics if 457 * successful, and start output if interface not yet active. 458 */ 459 return ((ifp->if_transmit)(ifp, m)); 460 } 461 462 /* 463 * Process a received Ethernet packet; the packet is in the 464 * mbuf chain m with the ethernet header at the front. 465 */ 466 static void 467 ether_input_internal(struct ifnet *ifp, struct mbuf *m) 468 { 469 struct ether_header *eh; 470 u_short etype; 471 472 if ((ifp->if_flags & IFF_UP) == 0) { 473 m_freem(m); 474 return; 475 } 476 #ifdef DIAGNOSTIC 477 if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0) { 478 if_printf(ifp, "discard frame at !IFF_DRV_RUNNING\n"); 479 m_freem(m); 480 return; 481 } 482 #endif 483 if (m->m_len < ETHER_HDR_LEN) { 484 /* XXX maybe should pullup? */ 485 if_printf(ifp, "discard frame w/o leading ethernet " 486 "header (len %u pkt len %u)\n", 487 m->m_len, m->m_pkthdr.len); 488 if_inc_counter(ifp, IFCOUNTER_IERRORS, 1); 489 m_freem(m); 490 return; 491 } 492 eh = mtod(m, struct ether_header *); 493 etype = ntohs(eh->ether_type); 494 random_harvest_queue(m, sizeof(*m), 2, RANDOM_NET_ETHER); 495 496 CURVNET_SET_QUIET(ifp->if_vnet); 497 498 if (ETHER_IS_MULTICAST(eh->ether_dhost)) { 499 if (ETHER_IS_BROADCAST(eh->ether_dhost)) 500 m->m_flags |= M_BCAST; 501 else 502 m->m_flags |= M_MCAST; 503 if_inc_counter(ifp, IFCOUNTER_IMCASTS, 1); 504 } 505 506 #ifdef MAC 507 /* 508 * Tag the mbuf with an appropriate MAC label before any other 509 * consumers can get to it. 510 */ 511 mac_ifnet_create_mbuf(ifp, m); 512 #endif 513 514 /* 515 * Give bpf a chance at the packet. 516 */ 517 ETHER_BPF_MTAP(ifp, m); 518 519 /* 520 * If the CRC is still on the packet, trim it off. We do this once 521 * and once only in case we are re-entered. Nothing else on the 522 * Ethernet receive path expects to see the FCS. 523 */ 524 if (m->m_flags & M_HASFCS) { 525 m_adj(m, -ETHER_CRC_LEN); 526 m->m_flags &= ~M_HASFCS; 527 } 528 529 if (!(ifp->if_capenable & IFCAP_HWSTATS)) 530 if_inc_counter(ifp, IFCOUNTER_IBYTES, m->m_pkthdr.len); 531 532 /* Allow monitor mode to claim this frame, after stats are updated. */ 533 if (ifp->if_flags & IFF_MONITOR) { 534 m_freem(m); 535 CURVNET_RESTORE(); 536 return; 537 } 538 539 /* Handle input from a lagg(4) port */ 540 if (ifp->if_type == IFT_IEEE8023ADLAG) { 541 KASSERT(lagg_input_p != NULL, 542 ("%s: if_lagg not loaded!", __func__)); 543 m = (*lagg_input_p)(ifp, m); 544 if (m != NULL) 545 ifp = m->m_pkthdr.rcvif; 546 else { 547 CURVNET_RESTORE(); 548 return; 549 } 550 } 551 552 /* 553 * If the hardware did not process an 802.1Q tag, do this now, 554 * to allow 802.1P priority frames to be passed to the main input 555 * path correctly. 556 * TODO: Deal with Q-in-Q frames, but not arbitrary nesting levels. 557 */ 558 if ((m->m_flags & M_VLANTAG) == 0 && etype == ETHERTYPE_VLAN) { 559 struct ether_vlan_header *evl; 560 561 if (m->m_len < sizeof(*evl) && 562 (m = m_pullup(m, sizeof(*evl))) == NULL) { 563 #ifdef DIAGNOSTIC 564 if_printf(ifp, "cannot pullup VLAN header\n"); 565 #endif 566 if_inc_counter(ifp, IFCOUNTER_IERRORS, 1); 567 CURVNET_RESTORE(); 568 return; 569 } 570 571 evl = mtod(m, struct ether_vlan_header *); 572 m->m_pkthdr.ether_vtag = ntohs(evl->evl_tag); 573 m->m_flags |= M_VLANTAG; 574 575 bcopy((char *)evl, (char *)evl + ETHER_VLAN_ENCAP_LEN, 576 ETHER_HDR_LEN - ETHER_TYPE_LEN); 577 m_adj(m, ETHER_VLAN_ENCAP_LEN); 578 eh = mtod(m, struct ether_header *); 579 } 580 581 M_SETFIB(m, ifp->if_fib); 582 583 /* Allow ng_ether(4) to claim this frame. */ 584 if (ifp->if_l2com != NULL) { 585 KASSERT(ng_ether_input_p != NULL, 586 ("%s: ng_ether_input_p is NULL", __func__)); 587 m->m_flags &= ~M_PROMISC; 588 (*ng_ether_input_p)(ifp, &m); 589 if (m == NULL) { 590 CURVNET_RESTORE(); 591 return; 592 } 593 eh = mtod(m, struct ether_header *); 594 } 595 596 /* 597 * Allow if_bridge(4) to claim this frame. 598 * The BRIDGE_INPUT() macro will update ifp if the bridge changed it 599 * and the frame should be delivered locally. 600 */ 601 if (ifp->if_bridge != NULL) { 602 m->m_flags &= ~M_PROMISC; 603 BRIDGE_INPUT(ifp, m); 604 if (m == NULL) { 605 CURVNET_RESTORE(); 606 return; 607 } 608 eh = mtod(m, struct ether_header *); 609 } 610 611 #if defined(INET) || defined(INET6) 612 /* 613 * Clear M_PROMISC on frame so that carp(4) will see it when the 614 * mbuf flows up to Layer 3. 615 * FreeBSD's implementation of carp(4) uses the inprotosw 616 * to dispatch IPPROTO_CARP. carp(4) also allocates its own 617 * Ethernet addresses of the form 00:00:5e:00:01:xx, which 618 * is outside the scope of the M_PROMISC test below. 619 * TODO: Maintain a hash table of ethernet addresses other than 620 * ether_dhost which may be active on this ifp. 621 */ 622 if (ifp->if_carp && (*carp_forus_p)(ifp, eh->ether_dhost)) { 623 m->m_flags &= ~M_PROMISC; 624 } else 625 #endif 626 { 627 /* 628 * If the frame received was not for our MAC address, set the 629 * M_PROMISC flag on the mbuf chain. The frame may need to 630 * be seen by the rest of the Ethernet input path in case of 631 * re-entry (e.g. bridge, vlan, netgraph) but should not be 632 * seen by upper protocol layers. 633 */ 634 if (!ETHER_IS_MULTICAST(eh->ether_dhost) && 635 bcmp(IF_LLADDR(ifp), eh->ether_dhost, ETHER_ADDR_LEN) != 0) 636 m->m_flags |= M_PROMISC; 637 } 638 639 ether_demux(ifp, m); 640 CURVNET_RESTORE(); 641 } 642 643 /* 644 * Ethernet input dispatch; by default, direct dispatch here regardless of 645 * global configuration. However, if RSS is enabled, hook up RSS affinity 646 * so that when deferred or hybrid dispatch is enabled, we can redistribute 647 * load based on RSS. 648 * 649 * XXXRW: Would be nice if the ifnet passed up a flag indicating whether or 650 * not it had already done work distribution via multi-queue. Then we could 651 * direct dispatch in the event load balancing was already complete and 652 * handle the case of interfaces with different capabilities better. 653 * 654 * XXXRW: Sort of want an M_DISTRIBUTED flag to avoid multiple distributions 655 * at multiple layers? 656 * 657 * XXXRW: For now, enable all this only if RSS is compiled in, although it 658 * works fine without RSS. Need to characterise the performance overhead 659 * of the detour through the netisr code in the event the result is always 660 * direct dispatch. 661 */ 662 static void 663 ether_nh_input(struct mbuf *m) 664 { 665 666 M_ASSERTPKTHDR(m); 667 KASSERT(m->m_pkthdr.rcvif != NULL, 668 ("%s: NULL interface pointer", __func__)); 669 ether_input_internal(m->m_pkthdr.rcvif, m); 670 } 671 672 static struct netisr_handler ether_nh = { 673 .nh_name = "ether", 674 .nh_handler = ether_nh_input, 675 .nh_proto = NETISR_ETHER, 676 #ifdef RSS 677 .nh_policy = NETISR_POLICY_CPU, 678 .nh_dispatch = NETISR_DISPATCH_DIRECT, 679 .nh_m2cpuid = rss_m2cpuid, 680 #else 681 .nh_policy = NETISR_POLICY_SOURCE, 682 .nh_dispatch = NETISR_DISPATCH_DIRECT, 683 #endif 684 }; 685 686 static void 687 ether_init(__unused void *arg) 688 { 689 690 netisr_register(ðer_nh); 691 } 692 SYSINIT(ether, SI_SUB_INIT_IF, SI_ORDER_ANY, ether_init, NULL); 693 694 static void 695 vnet_ether_init(__unused void *arg) 696 { 697 int i; 698 699 /* Initialize packet filter hooks. */ 700 V_link_pfil_hook.ph_type = PFIL_TYPE_AF; 701 V_link_pfil_hook.ph_af = AF_LINK; 702 if ((i = pfil_head_register(&V_link_pfil_hook)) != 0) 703 printf("%s: WARNING: unable to register pfil link hook, " 704 "error %d\n", __func__, i); 705 #ifdef VIMAGE 706 netisr_register_vnet(ðer_nh); 707 #endif 708 } 709 VNET_SYSINIT(vnet_ether_init, SI_SUB_PROTO_IF, SI_ORDER_ANY, 710 vnet_ether_init, NULL); 711 712 #ifdef VIMAGE 713 static void 714 vnet_ether_pfil_destroy(__unused void *arg) 715 { 716 int i; 717 718 if ((i = pfil_head_unregister(&V_link_pfil_hook)) != 0) 719 printf("%s: WARNING: unable to unregister pfil link hook, " 720 "error %d\n", __func__, i); 721 } 722 VNET_SYSUNINIT(vnet_ether_pfil_uninit, SI_SUB_PROTO_PFIL, SI_ORDER_ANY, 723 vnet_ether_pfil_destroy, NULL); 724 725 static void 726 vnet_ether_destroy(__unused void *arg) 727 { 728 729 netisr_unregister_vnet(ðer_nh); 730 } 731 VNET_SYSUNINIT(vnet_ether_uninit, SI_SUB_PROTO_IF, SI_ORDER_ANY, 732 vnet_ether_destroy, NULL); 733 #endif 734 735 736 737 static void 738 ether_input(struct ifnet *ifp, struct mbuf *m) 739 { 740 741 struct mbuf *mn; 742 743 /* 744 * The drivers are allowed to pass in a chain of packets linked with 745 * m_nextpkt. We split them up into separate packets here and pass 746 * them up. This allows the drivers to amortize the receive lock. 747 */ 748 while (m) { 749 mn = m->m_nextpkt; 750 m->m_nextpkt = NULL; 751 752 /* 753 * We will rely on rcvif being set properly in the deferred context, 754 * so assert it is correct here. 755 */ 756 KASSERT(m->m_pkthdr.rcvif == ifp, ("%s: ifnet mismatch m %p " 757 "rcvif %p ifp %p", __func__, m, m->m_pkthdr.rcvif, ifp)); 758 CURVNET_SET_QUIET(ifp->if_vnet); 759 netisr_dispatch(NETISR_ETHER, m); 760 CURVNET_RESTORE(); 761 m = mn; 762 } 763 } 764 765 /* 766 * Upper layer processing for a received Ethernet packet. 767 */ 768 void 769 ether_demux(struct ifnet *ifp, struct mbuf *m) 770 { 771 struct ether_header *eh; 772 int i, isr; 773 u_short ether_type; 774 775 KASSERT(ifp != NULL, ("%s: NULL interface pointer", __func__)); 776 777 /* Do not grab PROMISC frames in case we are re-entered. */ 778 if (PFIL_HOOKED(&V_link_pfil_hook) && !(m->m_flags & M_PROMISC)) { 779 i = pfil_run_hooks(&V_link_pfil_hook, &m, ifp, PFIL_IN, NULL); 780 781 if (i != 0 || m == NULL) 782 return; 783 } 784 785 eh = mtod(m, struct ether_header *); 786 ether_type = ntohs(eh->ether_type); 787 788 /* 789 * If this frame has a VLAN tag other than 0, call vlan_input() 790 * if its module is loaded. Otherwise, drop. 791 */ 792 if ((m->m_flags & M_VLANTAG) && 793 EVL_VLANOFTAG(m->m_pkthdr.ether_vtag) != 0) { 794 if (ifp->if_vlantrunk == NULL) { 795 if_inc_counter(ifp, IFCOUNTER_NOPROTO, 1); 796 m_freem(m); 797 return; 798 } 799 KASSERT(vlan_input_p != NULL,("%s: VLAN not loaded!", 800 __func__)); 801 /* Clear before possibly re-entering ether_input(). */ 802 m->m_flags &= ~M_PROMISC; 803 (*vlan_input_p)(ifp, m); 804 return; 805 } 806 807 /* 808 * Pass promiscuously received frames to the upper layer if the user 809 * requested this by setting IFF_PPROMISC. Otherwise, drop them. 810 */ 811 if ((ifp->if_flags & IFF_PPROMISC) == 0 && (m->m_flags & M_PROMISC)) { 812 m_freem(m); 813 return; 814 } 815 816 /* 817 * Reset layer specific mbuf flags to avoid confusing upper layers. 818 * Strip off Ethernet header. 819 */ 820 m->m_flags &= ~M_VLANTAG; 821 m_clrprotoflags(m); 822 m_adj(m, ETHER_HDR_LEN); 823 824 /* 825 * Dispatch frame to upper layer. 826 */ 827 switch (ether_type) { 828 #ifdef INET 829 case ETHERTYPE_IP: 830 isr = NETISR_IP; 831 break; 832 833 case ETHERTYPE_ARP: 834 if (ifp->if_flags & IFF_NOARP) { 835 /* Discard packet if ARP is disabled on interface */ 836 m_freem(m); 837 return; 838 } 839 isr = NETISR_ARP; 840 break; 841 #endif 842 #ifdef INET6 843 case ETHERTYPE_IPV6: 844 isr = NETISR_IPV6; 845 break; 846 #endif 847 default: 848 goto discard; 849 } 850 netisr_dispatch(isr, m); 851 return; 852 853 discard: 854 /* 855 * Packet is to be discarded. If netgraph is present, 856 * hand the packet to it for last chance processing; 857 * otherwise dispose of it. 858 */ 859 if (ifp->if_l2com != NULL) { 860 KASSERT(ng_ether_input_orphan_p != NULL, 861 ("ng_ether_input_orphan_p is NULL")); 862 /* 863 * Put back the ethernet header so netgraph has a 864 * consistent view of inbound packets. 865 */ 866 M_PREPEND(m, ETHER_HDR_LEN, M_NOWAIT); 867 (*ng_ether_input_orphan_p)(ifp, m); 868 return; 869 } 870 m_freem(m); 871 } 872 873 /* 874 * Convert Ethernet address to printable (loggable) representation. 875 * This routine is for compatibility; it's better to just use 876 * 877 * printf("%6D", <pointer to address>, ":"); 878 * 879 * since there's no static buffer involved. 880 */ 881 char * 882 ether_sprintf(const u_char *ap) 883 { 884 static char etherbuf[18]; 885 snprintf(etherbuf, sizeof (etherbuf), "%6D", ap, ":"); 886 return (etherbuf); 887 } 888 889 /* 890 * Perform common duties while attaching to interface list 891 */ 892 void 893 ether_ifattach(struct ifnet *ifp, const u_int8_t *lla) 894 { 895 int i; 896 struct ifaddr *ifa; 897 struct sockaddr_dl *sdl; 898 899 ifp->if_addrlen = ETHER_ADDR_LEN; 900 ifp->if_hdrlen = ETHER_HDR_LEN; 901 if_attach(ifp); 902 ifp->if_mtu = ETHERMTU; 903 ifp->if_output = ether_output; 904 ifp->if_input = ether_input; 905 ifp->if_resolvemulti = ether_resolvemulti; 906 ifp->if_requestencap = ether_requestencap; 907 #ifdef VIMAGE 908 ifp->if_reassign = ether_reassign; 909 #endif 910 if (ifp->if_baudrate == 0) 911 ifp->if_baudrate = IF_Mbps(10); /* just a default */ 912 ifp->if_broadcastaddr = etherbroadcastaddr; 913 914 ifa = ifp->if_addr; 915 KASSERT(ifa != NULL, ("%s: no lladdr!\n", __func__)); 916 sdl = (struct sockaddr_dl *)ifa->ifa_addr; 917 sdl->sdl_type = IFT_ETHER; 918 sdl->sdl_alen = ifp->if_addrlen; 919 bcopy(lla, LLADDR(sdl), ifp->if_addrlen); 920 921 bpfattach(ifp, DLT_EN10MB, ETHER_HDR_LEN); 922 if (ng_ether_attach_p != NULL) 923 (*ng_ether_attach_p)(ifp); 924 925 /* Announce Ethernet MAC address if non-zero. */ 926 for (i = 0; i < ifp->if_addrlen; i++) 927 if (lla[i] != 0) 928 break; 929 if (i != ifp->if_addrlen) 930 if_printf(ifp, "Ethernet address: %6D\n", lla, ":"); 931 932 uuid_ether_add(LLADDR(sdl)); 933 } 934 935 /* 936 * Perform common duties while detaching an Ethernet interface 937 */ 938 void 939 ether_ifdetach(struct ifnet *ifp) 940 { 941 struct sockaddr_dl *sdl; 942 943 sdl = (struct sockaddr_dl *)(ifp->if_addr->ifa_addr); 944 uuid_ether_del(LLADDR(sdl)); 945 946 if (ifp->if_l2com != NULL) { 947 KASSERT(ng_ether_detach_p != NULL, 948 ("ng_ether_detach_p is NULL")); 949 (*ng_ether_detach_p)(ifp); 950 } 951 952 bpfdetach(ifp); 953 if_detach(ifp); 954 } 955 956 #ifdef VIMAGE 957 void 958 ether_reassign(struct ifnet *ifp, struct vnet *new_vnet, char *unused __unused) 959 { 960 961 if (ifp->if_l2com != NULL) { 962 KASSERT(ng_ether_detach_p != NULL, 963 ("ng_ether_detach_p is NULL")); 964 (*ng_ether_detach_p)(ifp); 965 } 966 967 if (ng_ether_attach_p != NULL) { 968 CURVNET_SET_QUIET(new_vnet); 969 (*ng_ether_attach_p)(ifp); 970 CURVNET_RESTORE(); 971 } 972 } 973 #endif 974 975 SYSCTL_DECL(_net_link); 976 SYSCTL_NODE(_net_link, IFT_ETHER, ether, CTLFLAG_RW, 0, "Ethernet"); 977 978 #if 0 979 /* 980 * This is for reference. We have a table-driven version 981 * of the little-endian crc32 generator, which is faster 982 * than the double-loop. 983 */ 984 uint32_t 985 ether_crc32_le(const uint8_t *buf, size_t len) 986 { 987 size_t i; 988 uint32_t crc; 989 int bit; 990 uint8_t data; 991 992 crc = 0xffffffff; /* initial value */ 993 994 for (i = 0; i < len; i++) { 995 for (data = *buf++, bit = 0; bit < 8; bit++, data >>= 1) { 996 carry = (crc ^ data) & 1; 997 crc >>= 1; 998 if (carry) 999 crc = (crc ^ ETHER_CRC_POLY_LE); 1000 } 1001 } 1002 1003 return (crc); 1004 } 1005 #else 1006 uint32_t 1007 ether_crc32_le(const uint8_t *buf, size_t len) 1008 { 1009 static const uint32_t crctab[] = { 1010 0x00000000, 0x1db71064, 0x3b6e20c8, 0x26d930ac, 1011 0x76dc4190, 0x6b6b51f4, 0x4db26158, 0x5005713c, 1012 0xedb88320, 0xf00f9344, 0xd6d6a3e8, 0xcb61b38c, 1013 0x9b64c2b0, 0x86d3d2d4, 0xa00ae278, 0xbdbdf21c 1014 }; 1015 size_t i; 1016 uint32_t crc; 1017 1018 crc = 0xffffffff; /* initial value */ 1019 1020 for (i = 0; i < len; i++) { 1021 crc ^= buf[i]; 1022 crc = (crc >> 4) ^ crctab[crc & 0xf]; 1023 crc = (crc >> 4) ^ crctab[crc & 0xf]; 1024 } 1025 1026 return (crc); 1027 } 1028 #endif 1029 1030 uint32_t 1031 ether_crc32_be(const uint8_t *buf, size_t len) 1032 { 1033 size_t i; 1034 uint32_t crc, carry; 1035 int bit; 1036 uint8_t data; 1037 1038 crc = 0xffffffff; /* initial value */ 1039 1040 for (i = 0; i < len; i++) { 1041 for (data = *buf++, bit = 0; bit < 8; bit++, data >>= 1) { 1042 carry = ((crc & 0x80000000) ? 1 : 0) ^ (data & 0x01); 1043 crc <<= 1; 1044 if (carry) 1045 crc = (crc ^ ETHER_CRC_POLY_BE) | carry; 1046 } 1047 } 1048 1049 return (crc); 1050 } 1051 1052 int 1053 ether_ioctl(struct ifnet *ifp, u_long command, caddr_t data) 1054 { 1055 struct ifaddr *ifa = (struct ifaddr *) data; 1056 struct ifreq *ifr = (struct ifreq *) data; 1057 int error = 0; 1058 1059 switch (command) { 1060 case SIOCSIFADDR: 1061 ifp->if_flags |= IFF_UP; 1062 1063 switch (ifa->ifa_addr->sa_family) { 1064 #ifdef INET 1065 case AF_INET: 1066 ifp->if_init(ifp->if_softc); /* before arpwhohas */ 1067 arp_ifinit(ifp, ifa); 1068 break; 1069 #endif 1070 default: 1071 ifp->if_init(ifp->if_softc); 1072 break; 1073 } 1074 break; 1075 1076 case SIOCGIFADDR: 1077 { 1078 struct sockaddr *sa; 1079 1080 sa = (struct sockaddr *) & ifr->ifr_data; 1081 bcopy(IF_LLADDR(ifp), 1082 (caddr_t) sa->sa_data, ETHER_ADDR_LEN); 1083 } 1084 break; 1085 1086 case SIOCSIFMTU: 1087 /* 1088 * Set the interface MTU. 1089 */ 1090 if (ifr->ifr_mtu > ETHERMTU) { 1091 error = EINVAL; 1092 } else { 1093 ifp->if_mtu = ifr->ifr_mtu; 1094 } 1095 break; 1096 default: 1097 error = EINVAL; /* XXX netbsd has ENOTTY??? */ 1098 break; 1099 } 1100 return (error); 1101 } 1102 1103 static int 1104 ether_resolvemulti(struct ifnet *ifp, struct sockaddr **llsa, 1105 struct sockaddr *sa) 1106 { 1107 struct sockaddr_dl *sdl; 1108 #ifdef INET 1109 struct sockaddr_in *sin; 1110 #endif 1111 #ifdef INET6 1112 struct sockaddr_in6 *sin6; 1113 #endif 1114 u_char *e_addr; 1115 1116 switch(sa->sa_family) { 1117 case AF_LINK: 1118 /* 1119 * No mapping needed. Just check that it's a valid MC address. 1120 */ 1121 sdl = (struct sockaddr_dl *)sa; 1122 e_addr = LLADDR(sdl); 1123 if (!ETHER_IS_MULTICAST(e_addr)) 1124 return EADDRNOTAVAIL; 1125 *llsa = NULL; 1126 return 0; 1127 1128 #ifdef INET 1129 case AF_INET: 1130 sin = (struct sockaddr_in *)sa; 1131 if (!IN_MULTICAST(ntohl(sin->sin_addr.s_addr))) 1132 return EADDRNOTAVAIL; 1133 sdl = link_init_sdl(ifp, *llsa, IFT_ETHER); 1134 sdl->sdl_alen = ETHER_ADDR_LEN; 1135 e_addr = LLADDR(sdl); 1136 ETHER_MAP_IP_MULTICAST(&sin->sin_addr, e_addr); 1137 *llsa = (struct sockaddr *)sdl; 1138 return 0; 1139 #endif 1140 #ifdef INET6 1141 case AF_INET6: 1142 sin6 = (struct sockaddr_in6 *)sa; 1143 if (IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr)) { 1144 /* 1145 * An IP6 address of 0 means listen to all 1146 * of the Ethernet multicast address used for IP6. 1147 * (This is used for multicast routers.) 1148 */ 1149 ifp->if_flags |= IFF_ALLMULTI; 1150 *llsa = NULL; 1151 return 0; 1152 } 1153 if (!IN6_IS_ADDR_MULTICAST(&sin6->sin6_addr)) 1154 return EADDRNOTAVAIL; 1155 sdl = link_init_sdl(ifp, *llsa, IFT_ETHER); 1156 sdl->sdl_alen = ETHER_ADDR_LEN; 1157 e_addr = LLADDR(sdl); 1158 ETHER_MAP_IPV6_MULTICAST(&sin6->sin6_addr, e_addr); 1159 *llsa = (struct sockaddr *)sdl; 1160 return 0; 1161 #endif 1162 1163 default: 1164 /* 1165 * Well, the text isn't quite right, but it's the name 1166 * that counts... 1167 */ 1168 return EAFNOSUPPORT; 1169 } 1170 } 1171 1172 static moduledata_t ether_mod = { 1173 .name = "ether", 1174 }; 1175 1176 void 1177 ether_vlan_mtap(struct bpf_if *bp, struct mbuf *m, void *data, u_int dlen) 1178 { 1179 struct ether_vlan_header vlan; 1180 struct mbuf mv, mb; 1181 1182 KASSERT((m->m_flags & M_VLANTAG) != 0, 1183 ("%s: vlan information not present", __func__)); 1184 KASSERT(m->m_len >= sizeof(struct ether_header), 1185 ("%s: mbuf not large enough for header", __func__)); 1186 bcopy(mtod(m, char *), &vlan, sizeof(struct ether_header)); 1187 vlan.evl_proto = vlan.evl_encap_proto; 1188 vlan.evl_encap_proto = htons(ETHERTYPE_VLAN); 1189 vlan.evl_tag = htons(m->m_pkthdr.ether_vtag); 1190 m->m_len -= sizeof(struct ether_header); 1191 m->m_data += sizeof(struct ether_header); 1192 /* 1193 * If a data link has been supplied by the caller, then we will need to 1194 * re-create a stack allocated mbuf chain with the following structure: 1195 * 1196 * (1) mbuf #1 will contain the supplied data link 1197 * (2) mbuf #2 will contain the vlan header 1198 * (3) mbuf #3 will contain the original mbuf's packet data 1199 * 1200 * Otherwise, submit the packet and vlan header via bpf_mtap2(). 1201 */ 1202 if (data != NULL) { 1203 mv.m_next = m; 1204 mv.m_data = (caddr_t)&vlan; 1205 mv.m_len = sizeof(vlan); 1206 mb.m_next = &mv; 1207 mb.m_data = data; 1208 mb.m_len = dlen; 1209 bpf_mtap(bp, &mb); 1210 } else 1211 bpf_mtap2(bp, &vlan, sizeof(vlan), m); 1212 m->m_len += sizeof(struct ether_header); 1213 m->m_data -= sizeof(struct ether_header); 1214 } 1215 1216 struct mbuf * 1217 ether_vlanencap(struct mbuf *m, uint16_t tag) 1218 { 1219 struct ether_vlan_header *evl; 1220 1221 M_PREPEND(m, ETHER_VLAN_ENCAP_LEN, M_NOWAIT); 1222 if (m == NULL) 1223 return (NULL); 1224 /* M_PREPEND takes care of m_len, m_pkthdr.len for us */ 1225 1226 if (m->m_len < sizeof(*evl)) { 1227 m = m_pullup(m, sizeof(*evl)); 1228 if (m == NULL) 1229 return (NULL); 1230 } 1231 1232 /* 1233 * Transform the Ethernet header into an Ethernet header 1234 * with 802.1Q encapsulation. 1235 */ 1236 evl = mtod(m, struct ether_vlan_header *); 1237 bcopy((char *)evl + ETHER_VLAN_ENCAP_LEN, 1238 (char *)evl, ETHER_HDR_LEN - ETHER_TYPE_LEN); 1239 evl->evl_encap_proto = htons(ETHERTYPE_VLAN); 1240 evl->evl_tag = htons(tag); 1241 return (m); 1242 } 1243 1244 DECLARE_MODULE(ether, ether_mod, SI_SUB_INIT_IF, SI_ORDER_ANY); 1245 MODULE_VERSION(ether, 1);
Cache object: 6fa796bb5d0e613a8fc657a67b78a88f
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