1 /* 2 * INET 802.1Q VLAN 3 * Ethernet-type device handling. 4 * 5 * Authors: Ben Greear <greearb@candelatech.com> 6 * Please send support related email to: netdev@vger.kernel.org 7 * VLAN Home Page: http://www.candelatech.com/~greear/vlan.html 8 * 9 * Fixes: 10 * Fix for packet capture - Nick Eggleston <nick@dccinc.com>; 11 * Add HW acceleration hooks - David S. Miller <davem@redhat.com>; 12 * Correct all the locking - David S. Miller <davem@redhat.com>; 13 * Use hash table for VLAN groups - David S. Miller <davem@redhat.com> 14 * 15 * This program is free software; you can redistribute it and/or 16 * modify it under the terms of the GNU General Public License 17 * as published by the Free Software Foundation; either version 18 * 2 of the License, or (at your option) any later version. 19 */ 20 21 #include <asm/uaccess.h> /* for copy_from_user */ 22 #include <linux/capability.h> 23 #include <linux/module.h> 24 #include <linux/netdevice.h> 25 #include <linux/skbuff.h> 26 #include <net/datalink.h> 27 #include <linux/mm.h> 28 #include <linux/in.h> 29 #include <linux/init.h> 30 #include <net/p8022.h> 31 #include <net/arp.h> 32 #include <linux/rtnetlink.h> 33 #include <linux/notifier.h> 34 #include <net/net_namespace.h> 35 #include <net/netns/generic.h> 36 37 #include <linux/if_vlan.h> 38 #include "vlan.h" 39 #include "vlanproc.h" 40 41 #define DRV_VERSION "1.8" 42 43 /* Global VLAN variables */ 44 45 int vlan_net_id; 46 47 /* Our listing of VLAN group(s) */ 48 static struct hlist_head vlan_group_hash[VLAN_GRP_HASH_SIZE]; 49 50 static char vlan_fullname[] = "802.1Q VLAN Support"; 51 static char vlan_version[] = DRV_VERSION; 52 static char vlan_copyright[] = "Ben Greear <greearb@candelatech.com>"; 53 static char vlan_buggyright[] = "David S. Miller <davem@redhat.com>"; 54 55 static struct packet_type vlan_packet_type = { 56 .type = __constant_htons(ETH_P_8021Q), 57 .func = vlan_skb_recv, /* VLAN receive method */ 58 }; 59 60 /* End of global variables definitions. */ 61 62 static inline unsigned int vlan_grp_hashfn(unsigned int idx) 63 { 64 return ((idx >> VLAN_GRP_HASH_SHIFT) ^ idx) & VLAN_GRP_HASH_MASK; 65 } 66 67 /* Must be invoked with RCU read lock (no preempt) */ 68 static struct vlan_group *__vlan_find_group(struct net_device *real_dev) 69 { 70 struct vlan_group *grp; 71 struct hlist_node *n; 72 int hash = vlan_grp_hashfn(real_dev->ifindex); 73 74 hlist_for_each_entry_rcu(grp, n, &vlan_group_hash[hash], hlist) { 75 if (grp->real_dev == real_dev) 76 return grp; 77 } 78 79 return NULL; 80 } 81 82 /* Find the protocol handler. Assumes VID < VLAN_VID_MASK. 83 * 84 * Must be invoked with RCU read lock (no preempt) 85 */ 86 struct net_device *__find_vlan_dev(struct net_device *real_dev, 87 unsigned short VID) 88 { 89 struct vlan_group *grp = __vlan_find_group(real_dev); 90 91 if (grp) 92 return vlan_group_get_device(grp, VID); 93 94 return NULL; 95 } 96 97 static void vlan_group_free(struct vlan_group *grp) 98 { 99 int i; 100 101 for (i = 0; i < VLAN_GROUP_ARRAY_SPLIT_PARTS; i++) 102 kfree(grp->vlan_devices_arrays[i]); 103 kfree(grp); 104 } 105 106 static struct vlan_group *vlan_group_alloc(struct net_device *real_dev) 107 { 108 struct vlan_group *grp; 109 110 grp = kzalloc(sizeof(struct vlan_group), GFP_KERNEL); 111 if (!grp) 112 return NULL; 113 114 grp->real_dev = real_dev; 115 hlist_add_head_rcu(&grp->hlist, 116 &vlan_group_hash[vlan_grp_hashfn(real_dev->ifindex)]); 117 return grp; 118 } 119 120 static int vlan_group_prealloc_vid(struct vlan_group *vg, int vid) 121 { 122 struct net_device **array; 123 unsigned int size; 124 125 ASSERT_RTNL(); 126 127 array = vg->vlan_devices_arrays[vid / VLAN_GROUP_ARRAY_PART_LEN]; 128 if (array != NULL) 129 return 0; 130 131 size = sizeof(struct net_device *) * VLAN_GROUP_ARRAY_PART_LEN; 132 array = kzalloc(size, GFP_KERNEL); 133 if (array == NULL) 134 return -ENOBUFS; 135 136 vg->vlan_devices_arrays[vid / VLAN_GROUP_ARRAY_PART_LEN] = array; 137 return 0; 138 } 139 140 static void vlan_rcu_free(struct rcu_head *rcu) 141 { 142 vlan_group_free(container_of(rcu, struct vlan_group, rcu)); 143 } 144 145 void unregister_vlan_dev(struct net_device *dev) 146 { 147 struct vlan_dev_info *vlan = vlan_dev_info(dev); 148 struct net_device *real_dev = vlan->real_dev; 149 struct vlan_group *grp; 150 unsigned short vlan_id = vlan->vlan_id; 151 152 ASSERT_RTNL(); 153 154 grp = __vlan_find_group(real_dev); 155 BUG_ON(!grp); 156 157 /* Take it out of our own structures, but be sure to interlock with 158 * HW accelerating devices or SW vlan input packet processing. 159 */ 160 if (real_dev->features & NETIF_F_HW_VLAN_FILTER) 161 real_dev->vlan_rx_kill_vid(real_dev, vlan_id); 162 163 vlan_group_set_device(grp, vlan_id, NULL); 164 grp->nr_vlans--; 165 166 synchronize_net(); 167 168 /* If the group is now empty, kill off the group. */ 169 if (grp->nr_vlans == 0) { 170 if (real_dev->features & NETIF_F_HW_VLAN_RX) 171 real_dev->vlan_rx_register(real_dev, NULL); 172 173 hlist_del_rcu(&grp->hlist); 174 175 /* Free the group, after all cpu's are done. */ 176 call_rcu(&grp->rcu, vlan_rcu_free); 177 } 178 179 /* Get rid of the vlan's reference to real_dev */ 180 dev_put(real_dev); 181 182 unregister_netdevice(dev); 183 } 184 185 static void vlan_transfer_operstate(const struct net_device *dev, 186 struct net_device *vlandev) 187 { 188 /* Have to respect userspace enforced dormant state 189 * of real device, also must allow supplicant running 190 * on VLAN device 191 */ 192 if (dev->operstate == IF_OPER_DORMANT) 193 netif_dormant_on(vlandev); 194 else 195 netif_dormant_off(vlandev); 196 197 if (netif_carrier_ok(dev)) { 198 if (!netif_carrier_ok(vlandev)) 199 netif_carrier_on(vlandev); 200 } else { 201 if (netif_carrier_ok(vlandev)) 202 netif_carrier_off(vlandev); 203 } 204 } 205 206 int vlan_check_real_dev(struct net_device *real_dev, unsigned short vlan_id) 207 { 208 char *name = real_dev->name; 209 210 if (real_dev->features & NETIF_F_VLAN_CHALLENGED) { 211 pr_info("8021q: VLANs not supported on %s\n", name); 212 return -EOPNOTSUPP; 213 } 214 215 if ((real_dev->features & NETIF_F_HW_VLAN_RX) && 216 !real_dev->vlan_rx_register) { 217 pr_info("8021q: device %s has buggy VLAN hw accel\n", name); 218 return -EOPNOTSUPP; 219 } 220 221 if ((real_dev->features & NETIF_F_HW_VLAN_FILTER) && 222 (!real_dev->vlan_rx_add_vid || !real_dev->vlan_rx_kill_vid)) { 223 pr_info("8021q: Device %s has buggy VLAN hw accel\n", name); 224 return -EOPNOTSUPP; 225 } 226 227 /* The real device must be up and operating in order to 228 * assosciate a VLAN device with it. 229 */ 230 if (!(real_dev->flags & IFF_UP)) 231 return -ENETDOWN; 232 233 if (__find_vlan_dev(real_dev, vlan_id) != NULL) 234 return -EEXIST; 235 236 return 0; 237 } 238 239 int register_vlan_dev(struct net_device *dev) 240 { 241 struct vlan_dev_info *vlan = vlan_dev_info(dev); 242 struct net_device *real_dev = vlan->real_dev; 243 unsigned short vlan_id = vlan->vlan_id; 244 struct vlan_group *grp, *ngrp = NULL; 245 int err; 246 247 grp = __vlan_find_group(real_dev); 248 if (!grp) { 249 ngrp = grp = vlan_group_alloc(real_dev); 250 if (!grp) 251 return -ENOBUFS; 252 } 253 254 err = vlan_group_prealloc_vid(grp, vlan_id); 255 if (err < 0) 256 goto out_free_group; 257 258 err = register_netdevice(dev); 259 if (err < 0) 260 goto out_free_group; 261 262 /* Account for reference in struct vlan_dev_info */ 263 dev_hold(real_dev); 264 265 vlan_transfer_operstate(real_dev, dev); 266 linkwatch_fire_event(dev); /* _MUST_ call rfc2863_policy() */ 267 268 /* So, got the sucker initialized, now lets place 269 * it into our local structure. 270 */ 271 vlan_group_set_device(grp, vlan_id, dev); 272 grp->nr_vlans++; 273 274 if (ngrp && real_dev->features & NETIF_F_HW_VLAN_RX) 275 real_dev->vlan_rx_register(real_dev, ngrp); 276 if (real_dev->features & NETIF_F_HW_VLAN_FILTER) 277 real_dev->vlan_rx_add_vid(real_dev, vlan_id); 278 279 return 0; 280 281 out_free_group: 282 if (ngrp) 283 vlan_group_free(ngrp); 284 return err; 285 } 286 287 /* Attach a VLAN device to a mac address (ie Ethernet Card). 288 * Returns 0 if the device was created or a negative error code otherwise. 289 */ 290 static int register_vlan_device(struct net_device *real_dev, 291 unsigned short VLAN_ID) 292 { 293 struct net_device *new_dev; 294 struct net *net = dev_net(real_dev); 295 struct vlan_net *vn = net_generic(net, vlan_net_id); 296 char name[IFNAMSIZ]; 297 int err; 298 299 if (VLAN_ID >= VLAN_VID_MASK) 300 return -ERANGE; 301 302 err = vlan_check_real_dev(real_dev, VLAN_ID); 303 if (err < 0) 304 return err; 305 306 /* Gotta set up the fields for the device. */ 307 switch (vn->name_type) { 308 case VLAN_NAME_TYPE_RAW_PLUS_VID: 309 /* name will look like: eth1.0005 */ 310 snprintf(name, IFNAMSIZ, "%s.%.4i", real_dev->name, VLAN_ID); 311 break; 312 case VLAN_NAME_TYPE_PLUS_VID_NO_PAD: 313 /* Put our vlan.VID in the name. 314 * Name will look like: vlan5 315 */ 316 snprintf(name, IFNAMSIZ, "vlan%i", VLAN_ID); 317 break; 318 case VLAN_NAME_TYPE_RAW_PLUS_VID_NO_PAD: 319 /* Put our vlan.VID in the name. 320 * Name will look like: eth0.5 321 */ 322 snprintf(name, IFNAMSIZ, "%s.%i", real_dev->name, VLAN_ID); 323 break; 324 case VLAN_NAME_TYPE_PLUS_VID: 325 /* Put our vlan.VID in the name. 326 * Name will look like: vlan0005 327 */ 328 default: 329 snprintf(name, IFNAMSIZ, "vlan%.4i", VLAN_ID); 330 } 331 332 new_dev = alloc_netdev(sizeof(struct vlan_dev_info), name, 333 vlan_setup); 334 335 if (new_dev == NULL) 336 return -ENOBUFS; 337 338 dev_net_set(new_dev, net); 339 /* need 4 bytes for extra VLAN header info, 340 * hope the underlying device can handle it. 341 */ 342 new_dev->mtu = real_dev->mtu; 343 344 vlan_dev_info(new_dev)->vlan_id = VLAN_ID; /* 1 through VLAN_VID_MASK */ 345 vlan_dev_info(new_dev)->real_dev = real_dev; 346 vlan_dev_info(new_dev)->dent = NULL; 347 vlan_dev_info(new_dev)->flags = VLAN_FLAG_REORDER_HDR; 348 349 new_dev->rtnl_link_ops = &vlan_link_ops; 350 err = register_vlan_dev(new_dev); 351 if (err < 0) 352 goto out_free_newdev; 353 354 return 0; 355 356 out_free_newdev: 357 free_netdev(new_dev); 358 return err; 359 } 360 361 static void vlan_sync_address(struct net_device *dev, 362 struct net_device *vlandev) 363 { 364 struct vlan_dev_info *vlan = vlan_dev_info(vlandev); 365 366 /* May be called without an actual change */ 367 if (!compare_ether_addr(vlan->real_dev_addr, dev->dev_addr)) 368 return; 369 370 /* vlan address was different from the old address and is equal to 371 * the new address */ 372 if (compare_ether_addr(vlandev->dev_addr, vlan->real_dev_addr) && 373 !compare_ether_addr(vlandev->dev_addr, dev->dev_addr)) 374 dev_unicast_delete(dev, vlandev->dev_addr, ETH_ALEN); 375 376 /* vlan address was equal to the old address and is different from 377 * the new address */ 378 if (!compare_ether_addr(vlandev->dev_addr, vlan->real_dev_addr) && 379 compare_ether_addr(vlandev->dev_addr, dev->dev_addr)) 380 dev_unicast_add(dev, vlandev->dev_addr, ETH_ALEN); 381 382 memcpy(vlan->real_dev_addr, dev->dev_addr, ETH_ALEN); 383 } 384 385 static void __vlan_device_event(struct net_device *dev, unsigned long event) 386 { 387 switch (event) { 388 case NETDEV_CHANGENAME: 389 vlan_proc_rem_dev(dev); 390 if (vlan_proc_add_dev(dev) < 0) 391 pr_warning("8021q: failed to change proc name for %s\n", 392 dev->name); 393 break; 394 case NETDEV_REGISTER: 395 if (vlan_proc_add_dev(dev) < 0) 396 pr_warning("8021q: failed to add proc entry for %s\n", 397 dev->name); 398 break; 399 case NETDEV_UNREGISTER: 400 vlan_proc_rem_dev(dev); 401 break; 402 } 403 } 404 405 static int vlan_device_event(struct notifier_block *unused, unsigned long event, 406 void *ptr) 407 { 408 struct net_device *dev = ptr; 409 struct vlan_group *grp; 410 int i, flgs; 411 struct net_device *vlandev; 412 413 if (is_vlan_dev(dev)) { 414 __vlan_device_event(dev, event); 415 goto out; 416 } 417 418 grp = __vlan_find_group(dev); 419 if (!grp) 420 goto out; 421 422 /* It is OK that we do not hold the group lock right now, 423 * as we run under the RTNL lock. 424 */ 425 426 switch (event) { 427 case NETDEV_CHANGE: 428 /* Propagate real device state to vlan devices */ 429 for (i = 0; i < VLAN_GROUP_ARRAY_LEN; i++) { 430 vlandev = vlan_group_get_device(grp, i); 431 if (!vlandev) 432 continue; 433 434 vlan_transfer_operstate(dev, vlandev); 435 } 436 break; 437 438 case NETDEV_CHANGEADDR: 439 /* Adjust unicast filters on underlying device */ 440 for (i = 0; i < VLAN_GROUP_ARRAY_LEN; i++) { 441 vlandev = vlan_group_get_device(grp, i); 442 if (!vlandev) 443 continue; 444 445 flgs = vlandev->flags; 446 if (!(flgs & IFF_UP)) 447 continue; 448 449 vlan_sync_address(dev, vlandev); 450 } 451 break; 452 453 case NETDEV_DOWN: 454 /* Put all VLANs for this dev in the down state too. */ 455 for (i = 0; i < VLAN_GROUP_ARRAY_LEN; i++) { 456 vlandev = vlan_group_get_device(grp, i); 457 if (!vlandev) 458 continue; 459 460 flgs = vlandev->flags; 461 if (!(flgs & IFF_UP)) 462 continue; 463 464 dev_change_flags(vlandev, flgs & ~IFF_UP); 465 } 466 break; 467 468 case NETDEV_UP: 469 /* Put all VLANs for this dev in the up state too. */ 470 for (i = 0; i < VLAN_GROUP_ARRAY_LEN; i++) { 471 vlandev = vlan_group_get_device(grp, i); 472 if (!vlandev) 473 continue; 474 475 flgs = vlandev->flags; 476 if (flgs & IFF_UP) 477 continue; 478 479 dev_change_flags(vlandev, flgs | IFF_UP); 480 } 481 break; 482 483 case NETDEV_UNREGISTER: 484 /* Delete all VLANs for this dev. */ 485 for (i = 0; i < VLAN_GROUP_ARRAY_LEN; i++) { 486 vlandev = vlan_group_get_device(grp, i); 487 if (!vlandev) 488 continue; 489 490 /* unregistration of last vlan destroys group, abort 491 * afterwards */ 492 if (grp->nr_vlans == 1) 493 i = VLAN_GROUP_ARRAY_LEN; 494 495 unregister_vlan_dev(vlandev); 496 } 497 break; 498 } 499 500 out: 501 return NOTIFY_DONE; 502 } 503 504 static struct notifier_block vlan_notifier_block __read_mostly = { 505 .notifier_call = vlan_device_event, 506 }; 507 508 /* 509 * VLAN IOCTL handler. 510 * o execute requested action or pass command to the device driver 511 * arg is really a struct vlan_ioctl_args __user *. 512 */ 513 static int vlan_ioctl_handler(struct net *net, void __user *arg) 514 { 515 int err; 516 unsigned short vid = 0; 517 struct vlan_ioctl_args args; 518 struct net_device *dev = NULL; 519 520 if (copy_from_user(&args, arg, sizeof(struct vlan_ioctl_args))) 521 return -EFAULT; 522 523 /* Null terminate this sucker, just in case. */ 524 args.device1[23] = 0; 525 args.u.device2[23] = 0; 526 527 rtnl_lock(); 528 529 switch (args.cmd) { 530 case SET_VLAN_INGRESS_PRIORITY_CMD: 531 case SET_VLAN_EGRESS_PRIORITY_CMD: 532 case SET_VLAN_FLAG_CMD: 533 case ADD_VLAN_CMD: 534 case DEL_VLAN_CMD: 535 case GET_VLAN_REALDEV_NAME_CMD: 536 case GET_VLAN_VID_CMD: 537 err = -ENODEV; 538 dev = __dev_get_by_name(net, args.device1); 539 if (!dev) 540 goto out; 541 542 err = -EINVAL; 543 if (args.cmd != ADD_VLAN_CMD && 544 !(dev->priv_flags & IFF_802_1Q_VLAN)) 545 goto out; 546 } 547 548 switch (args.cmd) { 549 case SET_VLAN_INGRESS_PRIORITY_CMD: 550 err = -EPERM; 551 if (!capable(CAP_NET_ADMIN)) 552 break; 553 vlan_dev_set_ingress_priority(dev, 554 args.u.skb_priority, 555 args.vlan_qos); 556 err = 0; 557 break; 558 559 case SET_VLAN_EGRESS_PRIORITY_CMD: 560 err = -EPERM; 561 if (!capable(CAP_NET_ADMIN)) 562 break; 563 err = vlan_dev_set_egress_priority(dev, 564 args.u.skb_priority, 565 args.vlan_qos); 566 break; 567 568 case SET_VLAN_FLAG_CMD: 569 err = -EPERM; 570 if (!capable(CAP_NET_ADMIN)) 571 break; 572 err = vlan_dev_set_vlan_flag(dev, 573 args.u.flag, 574 args.vlan_qos); 575 break; 576 577 case SET_VLAN_NAME_TYPE_CMD: 578 err = -EPERM; 579 if (!capable(CAP_NET_ADMIN)) 580 break; 581 if ((args.u.name_type >= 0) && 582 (args.u.name_type < VLAN_NAME_TYPE_HIGHEST)) { 583 struct vlan_net *vn; 584 585 vn = net_generic(net, vlan_net_id); 586 vn->name_type = args.u.name_type; 587 err = 0; 588 } else { 589 err = -EINVAL; 590 } 591 break; 592 593 case ADD_VLAN_CMD: 594 err = -EPERM; 595 if (!capable(CAP_NET_ADMIN)) 596 break; 597 err = register_vlan_device(dev, args.u.VID); 598 break; 599 600 case DEL_VLAN_CMD: 601 err = -EPERM; 602 if (!capable(CAP_NET_ADMIN)) 603 break; 604 unregister_vlan_dev(dev); 605 err = 0; 606 break; 607 608 case GET_VLAN_REALDEV_NAME_CMD: 609 err = 0; 610 vlan_dev_get_realdev_name(dev, args.u.device2); 611 if (copy_to_user(arg, &args, 612 sizeof(struct vlan_ioctl_args))) 613 err = -EFAULT; 614 break; 615 616 case GET_VLAN_VID_CMD: 617 err = 0; 618 vlan_dev_get_vid(dev, &vid); 619 args.u.VID = vid; 620 if (copy_to_user(arg, &args, 621 sizeof(struct vlan_ioctl_args))) 622 err = -EFAULT; 623 break; 624 625 default: 626 err = -EOPNOTSUPP; 627 break; 628 } 629 out: 630 rtnl_unlock(); 631 return err; 632 } 633 634 static int vlan_init_net(struct net *net) 635 { 636 int err; 637 struct vlan_net *vn; 638 639 err = -ENOMEM; 640 vn = kzalloc(sizeof(struct vlan_net), GFP_KERNEL); 641 if (vn == NULL) 642 goto err_alloc; 643 644 err = net_assign_generic(net, vlan_net_id, vn); 645 if (err < 0) 646 goto err_assign; 647 648 vn->name_type = VLAN_NAME_TYPE_RAW_PLUS_VID_NO_PAD; 649 650 err = vlan_proc_init(net); 651 if (err < 0) 652 goto err_proc; 653 654 return 0; 655 656 err_proc: 657 /* nothing */ 658 err_assign: 659 kfree(vn); 660 err_alloc: 661 return err; 662 } 663 664 static void vlan_exit_net(struct net *net) 665 { 666 struct vlan_net *vn; 667 668 vn = net_generic(net, vlan_net_id); 669 rtnl_kill_links(net, &vlan_link_ops); 670 vlan_proc_cleanup(net); 671 kfree(vn); 672 } 673 674 static struct pernet_operations vlan_net_ops = { 675 .init = vlan_init_net, 676 .exit = vlan_exit_net, 677 }; 678 679 static int __init vlan_proto_init(void) 680 { 681 int err; 682 683 pr_info("%s v%s %s\n", vlan_fullname, vlan_version, vlan_copyright); 684 pr_info("All bugs added by %s\n", vlan_buggyright); 685 686 err = register_pernet_gen_device(&vlan_net_id, &vlan_net_ops); 687 if (err < 0) 688 goto err0; 689 690 err = register_netdevice_notifier(&vlan_notifier_block); 691 if (err < 0) 692 goto err2; 693 694 err = vlan_netlink_init(); 695 if (err < 0) 696 goto err3; 697 698 dev_add_pack(&vlan_packet_type); 699 vlan_ioctl_set(vlan_ioctl_handler); 700 return 0; 701 702 err3: 703 unregister_netdevice_notifier(&vlan_notifier_block); 704 err2: 705 unregister_pernet_gen_device(vlan_net_id, &vlan_net_ops); 706 err0: 707 return err; 708 } 709 710 static void __exit vlan_cleanup_module(void) 711 { 712 unsigned int i; 713 714 vlan_ioctl_set(NULL); 715 vlan_netlink_fini(); 716 717 unregister_netdevice_notifier(&vlan_notifier_block); 718 719 dev_remove_pack(&vlan_packet_type); 720 721 /* This table must be empty if there are no module references left. */ 722 for (i = 0; i < VLAN_GRP_HASH_SIZE; i++) 723 BUG_ON(!hlist_empty(&vlan_group_hash[i])); 724 725 unregister_pernet_gen_device(vlan_net_id, &vlan_net_ops); 726 727 synchronize_net(); 728 } 729 730 module_init(vlan_proto_init); 731 module_exit(vlan_cleanup_module); 732 733 MODULE_LICENSE("GPL"); 734 MODULE_VERSION(DRV_VERSION); 735