net/8021q/vlan_dev.c

   1 /* -*- linux-c -*-
   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: vlan@scry.wanfear.com
   7  *              VLAN Home Page: http://www.candelatech.com/~greear/vlan.html
   8  *
   9  * Fixes:       Mar 22 2001: Martin Bokaemper <mbokaemper@unispherenetworks.com>
  10  *                - reset skb->pkt_type on incoming packets when MAC was changed
  11  *                - see that changed MAC is saddr for outgoing packets
  12  *              Oct 20, 2001:  Ard van Breeman:
  13  *                - Fix MC-list, finally.
  14  *                - Flush MC-list on VLAN destroy.
  15  *
  16  *
  17  *              This program is free software; you can redistribute it and/or
  18  *              modify it under the terms of the GNU General Public License
  19  *              as published by the Free Software Foundation; either version
  20  *              2 of the License, or (at your option) any later version.
  21  */
  22
  23 #include <linux/module.h>
  24 #include <linux/mm.h>
  25 #include <linux/in.h>
  26 #include <linux/init.h>
  27 #include <asm/uaccess.h> /* for copy_from_user */
  28 #include <linux/skbuff.h>
  29 #include <linux/netdevice.h>
  30 #include <linux/etherdevice.h>
  31 #include <net/datalink.h>
  32 #include <net/p8022.h>
  33 #include <net/arp.h>
  34
  35 #include "vlan.h"
  36 #include "vlanproc.h"
  37 #include <linux/if_vlan.h>
  38 #include <net/ip.h>
  39
  40 /*
  41  *      Rebuild the Ethernet MAC header. This is called after an ARP
  42  *      (or in future other address resolution) has completed on this
  43  *      sk_buff. We now let ARP fill in the other fields.
  44  *
  45  *      This routine CANNOT use cached dst->neigh!
  46  *      Really, it is used only when dst->neigh is wrong.
  47  *
  48  * TODO:  This needs a checkup, I'm ignorant here. --BLG
  49  */
  50 int vlan_dev_rebuild_header(struct sk_buff *skb)
  51 {
  52         struct net_device *dev = skb->dev;
  53         struct vlan_ethhdr *veth = (struct vlan_ethhdr *)(skb->data);
  54
  55         switch (veth->h_vlan_encapsulated_proto) {
  56 #ifdef CONFIG_INET
  57         case __constant_htons(ETH_P_IP):
  58
  59                 /* TODO:  Confirm this will work with VLAN headers... */
  60                 return arp_find(veth->h_dest, skb);
  61 #endif
  62         default:
  63                 printk(VLAN_DBG
  64                        "%s: unable to resolve type %X addresses.\n",
  65                        dev->name, ntohs(veth->h_vlan_encapsulated_proto));
  66
  67                 memcpy(veth->h_source, dev->dev_addr, ETH_ALEN);
  68                 break;
  69         };
  70
  71         return 0;
  72 }
  73
  74 static inline struct sk_buff *vlan_check_reorder_header(struct sk_buff *skb)
  75 {
  76         if (VLAN_DEV_INFO(skb->dev)->flags & 1) {
  77                 if (skb_shared(skb) || skb_cloned(skb)) {
  78                         struct sk_buff *nskb = skb_copy(skb, GFP_ATOMIC);
  79                         kfree_skb(skb);
  80                         skb = nskb;
  81                 }
  82                 if (skb) {
  83                         /* Lifted from Gleb's VLAN code... */
  84                         memmove(skb->data - ETH_HLEN,
  85                                 skb->data - VLAN_ETH_HLEN, 12);
  86                         skb->mac.raw += VLAN_HLEN;
  87                 }
  88         }
  89
  90         return skb;
  91 }
  92
  93 /*
  94  *      Determine the packet's protocol ID. The rule here is that we
  95  *      assume 802.3 if the type field is short enough to be a length.
  96  *      This is normal practice and works for any 'now in use' protocol.
  97  *
  98  *  Also, at this point we assume that we ARE dealing exclusively with
  99  *  VLAN packets, or packets that should be made into VLAN packets based
 100  *  on a default VLAN ID.
 101  *
 102  *  NOTE:  Should be similar to ethernet/eth.c.
 103  *
 104  *  SANITY NOTE:  This method is called when a packet is moving up the stack
 105  *                towards userland.  To get here, it would have already passed
 106  *                through the ethernet/eth.c eth_type_trans() method.
 107  *  SANITY NOTE 2: We are referencing to the VLAN_HDR frields, which MAY be
 108  *                 stored UNALIGNED in the memory.  RISC systems don't like
 109  *                 such cases very much...
 110  *  SANITY NOTE 2a:  According to Dave Miller & Alexey, it will always be aligned,
 111  *                 so there doesn't need to be any of the unaligned stuff.  It has
 112  *                 been commented out now...  --Ben
 113  *
 114  */
 115 int vlan_skb_recv(struct sk_buff *skb, struct net_device *dev,
 116                   struct packet_type* ptype, struct net_device *orig_dev)
 117 {
 118         unsigned char *rawp = NULL;
 119         struct vlan_hdr *vhdr = (struct vlan_hdr *)(skb->data);
 120         unsigned short vid;
 121         struct net_device_stats *stats;
 122         unsigned short vlan_TCI;
 123         __be16 proto;
 124
 125         /* vlan_TCI = ntohs(get_unaligned(&vhdr->h_vlan_TCI)); */
 126         vlan_TCI = ntohs(vhdr->h_vlan_TCI);
 127
 128         vid = (vlan_TCI & VLAN_VID_MASK);
 129
 130 #ifdef VLAN_DEBUG
 131         printk(VLAN_DBG "%s: skb: %p vlan_id: %hx\n",
 132                 __FUNCTION__, skb, vid);
 133 #endif
 134
 135         /* Ok, we will find the correct VLAN device, strip the header,
 136          * and then go on as usual.
 137          */
 138
 139         /* We have 12 bits of vlan ID.
 140          *
 141          * We must not drop allow preempt until we hold a
 142          * reference to the device (netif_rx does that) or we
 143          * fail.
 144          */
 145
 146         rcu_read_lock();
 147         skb->dev = __find_vlan_dev(dev, vid);
 148         if (!skb->dev) {
 149                 rcu_read_unlock();
 150
 151 #ifdef VLAN_DEBUG
 152                 printk(VLAN_DBG "%s: ERROR: No net_device for VID: %i on dev: %s [%i]\n",
 153                         __FUNCTION__, (unsigned int)(vid), dev->name, dev->ifindex);
 154 #endif
 155                 kfree_skb(skb);
 156                 return -1;
 157         }
 158
 159         skb->dev->last_rx = jiffies;
 160
 161         /* Bump the rx counters for the VLAN device. */
 162         stats = vlan_dev_get_stats(skb->dev);
 163         stats->rx_packets++;
 164         stats->rx_bytes += skb->len;
 165
 166         /* Take off the VLAN header (4 bytes currently) */
 167         skb_pull_rcsum(skb, VLAN_HLEN);
 168
 169         /* Ok, lets check to make sure the device (dev) we
 170          * came in on is what this VLAN is attached to.
 171          */
 172
 173         if (dev != VLAN_DEV_INFO(skb->dev)->real_dev) {
 174                 rcu_read_unlock();
 175
 176 #ifdef VLAN_DEBUG
 177                 printk(VLAN_DBG "%s: dropping skb: %p because came in on wrong device, dev: %s  real_dev: %s, skb_dev: %s\n",
 178                         __FUNCTION__, skb, dev->name,
 179                         VLAN_DEV_INFO(skb->dev)->real_dev->name,
 180                         skb->dev->name);
 181 #endif
 182                 kfree_skb(skb);
 183                 stats->rx_errors++;
 184                 return -1;
 185         }
 186
 187         /*
 188          * Deal with ingress priority mapping.
 189          */
 190         skb->priority = vlan_get_ingress_priority(skb->dev, ntohs(vhdr->h_vlan_TCI));
 191
 192 #ifdef VLAN_DEBUG
 193         printk(VLAN_DBG "%s: priority: %lu  for TCI: %hu (hbo)\n",
 194                 __FUNCTION__, (unsigned long)(skb->priority),
 195                 ntohs(vhdr->h_vlan_TCI));
 196 #endif
 197
 198         /* The ethernet driver already did the pkt_type calculations
 199          * for us...
 200          */
 201         switch (skb->pkt_type) {
 202         case PACKET_BROADCAST: /* Yeah, stats collect these together.. */
 203                 // stats->broadcast ++; // no such counter :-(
 204                 break;
 205
 206         case PACKET_MULTICAST:
 207                 stats->multicast++;
 208                 break;
 209
 210         case PACKET_OTHERHOST:
 211                 /* Our lower layer thinks this is not local, let's make sure.
 212                  * This allows the VLAN to have a different MAC than the underlying
 213                  * device, and still route correctly.
 214                  */
 215                 if (!compare_ether_addr(eth_hdr(skb)->h_dest, skb->dev->dev_addr)) {
 216                         /* It is for our (changed) MAC-address! */
 217                         skb->pkt_type = PACKET_HOST;
 218                 }
 219                 break;
 220         default:
 221                 break;
 222         };
 223
 224         /*  Was a VLAN packet, grab the encapsulated protocol, which the layer
 225          * three protocols care about.
 226          */
 227         /* proto = get_unaligned(&vhdr->h_vlan_encapsulated_proto); */
 228         proto = vhdr->h_vlan_encapsulated_proto;
 229
 230         skb->protocol = proto;
 231         if (ntohs(proto) >= 1536) {
 232                 /* place it back on the queue to be handled by
 233                  * true layer 3 protocols.
 234                  */
 235
 236                 /* See if we are configured to re-write the VLAN header
 237                  * to make it look like ethernet...
 238                  */
 239                 skb = vlan_check_reorder_header(skb);
 240
 241                 /* Can be null if skb-clone fails when re-ordering */
 242                 if (skb) {
 243                         netif_rx(skb);
 244                 } else {
 245                         /* TODO:  Add a more specific counter here. */
 246                         stats->rx_errors++;
 247                 }
 248                 rcu_read_unlock();
 249                 return 0;
 250         }
 251
 252         rawp = skb->data;
 253
 254         /*
 255          * This is a magic hack to spot IPX packets. Older Novell breaks
 256          * the protocol design and runs IPX over 802.3 without an 802.2 LLC
 257          * layer. We look for FFFF which isn't a used 802.2 SSAP/DSAP. This
 258          * won't work for fault tolerant netware but does for the rest.
 259          */
 260         if (*(unsigned short *)rawp == 0xFFFF) {
 261                 skb->protocol = __constant_htons(ETH_P_802_3);
 262                 /* place it back on the queue to be handled by true layer 3 protocols.
 263                  */
 264
 265                 /* See if we are configured to re-write the VLAN header
 266                  * to make it look like ethernet...
 267                  */
 268                 skb = vlan_check_reorder_header(skb);
 269
 270                 /* Can be null if skb-clone fails when re-ordering */
 271                 if (skb) {
 272                         netif_rx(skb);
 273                 } else {
 274                         /* TODO:  Add a more specific counter here. */
 275                         stats->rx_errors++;
 276                 }
 277                 rcu_read_unlock();
 278                 return 0;
 279         }
 280
 281         /*
 282          *      Real 802.2 LLC
 283          */
 284         skb->protocol = __constant_htons(ETH_P_802_2);
 285         /* place it back on the queue to be handled by upper layer protocols.
 286          */
 287
 288         /* See if we are configured to re-write the VLAN header
 289          * to make it look like ethernet...
 290          */
 291         skb = vlan_check_reorder_header(skb);
 292
 293         /* Can be null if skb-clone fails when re-ordering */
 294         if (skb) {
 295                 netif_rx(skb);
 296         } else {
 297                 /* TODO:  Add a more specific counter here. */
 298                 stats->rx_errors++;
 299         }
 300         rcu_read_unlock();
 301         return 0;
 302 }
 303
 304 static inline unsigned short vlan_dev_get_egress_qos_mask(struct net_device* dev,
 305                                                           struct sk_buff* skb)
 306 {
 307         struct vlan_priority_tci_mapping *mp =
 308                 VLAN_DEV_INFO(dev)->egress_priority_map[(skb->priority & 0xF)];
 309
 310         while (mp) {
 311                 if (mp->priority == skb->priority) {
 312                         return mp->vlan_qos; /* This should already be shifted to mask
 313                                               * correctly with the VLAN's TCI
 314                                               */
 315                 }
 316                 mp = mp->next;
 317         }
 318         return 0;
 319 }
 320
 321 /*
 322  *      Create the VLAN header for an arbitrary protocol layer
 323  *
 324  *      saddr=NULL      means use device source address
 325  *      daddr=NULL      means leave destination address (eg unresolved arp)
 326  *
 327  *  This is called when the SKB is moving down the stack towards the
 328  *  physical devices.
 329  */
 330 int vlan_dev_hard_header(struct sk_buff *skb, struct net_device *dev,
 331                          unsigned short type, void *daddr, void *saddr,
 332                          unsigned len)
 333 {
 334         struct vlan_hdr *vhdr;
 335         unsigned short veth_TCI = 0;
 336         int rc = 0;
 337         int build_vlan_header = 0;
 338         struct net_device *vdev = dev; /* save this for the bottom of the method */
 339
 340 #ifdef VLAN_DEBUG
 341         printk(VLAN_DBG "%s: skb: %p type: %hx len: %x vlan_id: %hx, daddr: %p\n",
 342                 __FUNCTION__, skb, type, len, VLAN_DEV_INFO(dev)->vlan_id, daddr);
 343 #endif
 344
 345         /* build vlan header only if re_order_header flag is NOT set.  This
 346          * fixes some programs that get confused when they see a VLAN device
 347          * sending a frame that is VLAN encoded (the consensus is that the VLAN
 348          * device should look completely like an Ethernet device when the
 349          * REORDER_HEADER flag is set)  The drawback to this is some extra
 350          * header shuffling in the hard_start_xmit.  Users can turn off this
 351          * REORDER behaviour with the vconfig tool.
 352          */
 353         build_vlan_header = ((VLAN_DEV_INFO(dev)->flags & 1) == 0);
 354
 355         if (build_vlan_header) {
 356                 vhdr = (struct vlan_hdr *) skb_push(skb, VLAN_HLEN);
 357
 358                 /* build the four bytes that make this a VLAN header. */
 359
 360                 /* Now, construct the second two bytes. This field looks something
 361                  * like:
 362                  * usr_priority: 3 bits  (high bits)
 363                  * CFI           1 bit
 364                  * VLAN ID       12 bits (low bits)
 365                  *
 366                  */
 367                 veth_TCI = VLAN_DEV_INFO(dev)->vlan_id;
 368                 veth_TCI |= vlan_dev_get_egress_qos_mask(dev, skb);
 369
 370                 vhdr->h_vlan_TCI = htons(veth_TCI);
 371
 372                 /*
 373                  *  Set the protocol type.
 374                  *  For a packet of type ETH_P_802_3 we put the length in here instead.
 375                  *  It is up to the 802.2 layer to carry protocol information.
 376                  */
 377
 378                 if (type != ETH_P_802_3) {
 379                         vhdr->h_vlan_encapsulated_proto = htons(type);
 380                 } else {
 381                         vhdr->h_vlan_encapsulated_proto = htons(len);
 382                 }
 383
 384                 skb->protocol = htons(ETH_P_8021Q);
 385                 skb->nh.raw = skb->data;
 386         }
 387
 388         /* Before delegating work to the lower layer, enter our MAC-address */
 389         if (saddr == NULL)
 390                 saddr = dev->dev_addr;
 391
 392         dev = VLAN_DEV_INFO(dev)->real_dev;
 393
 394         /* MPLS can send us skbuffs w/out enough space.  This check will grow the
 395          * skb if it doesn't have enough headroom.  Not a beautiful solution, so
 396          * I'll tick a counter so that users can know it's happening...  If they
 397          * care...
 398          */
 399
 400         /* NOTE:  This may still break if the underlying device is not the final
 401          * device (and thus there are more headers to add...)  It should work for
 402          * good-ole-ethernet though.
 403          */
 404         if (skb_headroom(skb) < dev->hard_header_len) {
 405                 struct sk_buff *sk_tmp = skb;
 406                 skb = skb_realloc_headroom(sk_tmp, dev->hard_header_len);
 407                 kfree_skb(sk_tmp);
 408                 if (skb == NULL) {
 409                         struct net_device_stats *stats = vlan_dev_get_stats(vdev);
 410                         stats->tx_dropped++;
 411                         return -ENOMEM;
 412                 }
 413                 VLAN_DEV_INFO(vdev)->cnt_inc_headroom_on_tx++;
 414 #ifdef VLAN_DEBUG
 415                 printk(VLAN_DBG "%s: %s: had to grow skb.\n", __FUNCTION__, vdev->name);
 416 #endif
 417         }
 418
 419         if (build_vlan_header) {
 420                 /* Now make the underlying real hard header */
 421                 rc = dev->hard_header(skb, dev, ETH_P_8021Q, daddr, saddr, len + VLAN_HLEN);
 422
 423                 if (rc > 0) {
 424                         rc += VLAN_HLEN;
 425                 } else if (rc < 0) {
 426                         rc -= VLAN_HLEN;
 427                 }
 428         } else {
 429                 /* If here, then we'll just make a normal looking ethernet frame,
 430                  * but, the hard_start_xmit method will insert the tag (it has to
 431                  * be able to do this for bridged and other skbs that don't come
 432                  * down the protocol stack in an orderly manner.
 433                  */
 434                 rc = dev->hard_header(skb, dev, type, daddr, saddr, len);
 435         }
 436
 437         return rc;
 438 }
 439
 440 int vlan_dev_hard_start_xmit(struct sk_buff *skb, struct net_device *dev)
 441 {
 442         struct net_device_stats *stats = vlan_dev_get_stats(dev);
 443         struct vlan_ethhdr *veth = (struct vlan_ethhdr *)(skb->data);
 444
 445         /* Handle non-VLAN frames if they are sent to us, for example by DHCP.
 446          *
 447          * NOTE: THIS ASSUMES DIX ETHERNET, SPECIFICALLY NOT SUPPORTING
 448          * OTHER THINGS LIKE FDDI/TokenRing/802.3 SNAPs...
 449          */
 450
 451         if (veth->h_vlan_proto != __constant_htons(ETH_P_8021Q)) {
 452                 int orig_headroom = skb_headroom(skb);
 453                 unsigned short veth_TCI;
 454
 455                 /* This is not a VLAN frame...but we can fix that! */
 456                 VLAN_DEV_INFO(dev)->cnt_encap_on_xmit++;
 457
 458 #ifdef VLAN_DEBUG
 459                 printk(VLAN_DBG "%s: proto to encap: 0x%hx (hbo)\n",
 460                         __FUNCTION__, htons(veth->h_vlan_proto));
 461 #endif
 462                 /* Construct the second two bytes. This field looks something
 463                  * like:
 464                  * usr_priority: 3 bits  (high bits)
 465                  * CFI           1 bit
 466                  * VLAN ID       12 bits (low bits)
 467                  */
 468                 veth_TCI = VLAN_DEV_INFO(dev)->vlan_id;
 469                 veth_TCI |= vlan_dev_get_egress_qos_mask(dev, skb);
 470
 471                 skb = __vlan_put_tag(skb, veth_TCI);
 472                 if (!skb) {
 473                         stats->tx_dropped++;
 474                         return 0;
 475                 }
 476
 477                 if (orig_headroom < VLAN_HLEN) {
 478                         VLAN_DEV_INFO(dev)->cnt_inc_headroom_on_tx++;
 479                 }
 480         }
 481
 482 #ifdef VLAN_DEBUG
 483         printk(VLAN_DBG "%s: about to send skb: %p to dev: %s\n",
 484                 __FUNCTION__, skb, skb->dev->name);
 485         printk(VLAN_DBG "  %2hx.%2hx.%2hx.%2xh.%2hx.%2hx %2hx.%2hx.%2hx.%2hx.%2hx.%2hx %4hx %4hx %4hx\n",
 486                veth->h_dest[0], veth->h_dest[1], veth->h_dest[2], veth->h_dest[3], veth->h_dest[4], veth->h_dest[5],
 487                veth->h_source[0], veth->h_source[1], veth->h_source[2], veth->h_source[3], veth->h_source[4], veth->h_source[5],
 488                veth->h_vlan_proto, veth->h_vlan_TCI, veth->h_vlan_encapsulated_proto);
 489 #endif
 490
 491         stats->tx_packets++; /* for statics only */
 492         stats->tx_bytes += skb->len;
 493
 494         skb->dev = VLAN_DEV_INFO(dev)->real_dev;
 495         dev_queue_xmit(skb);
 496
 497         return 0;
 498 }
 499
 500 int vlan_dev_hwaccel_hard_start_xmit(struct sk_buff *skb, struct net_device *dev)
 501 {
 502         struct net_device_stats *stats = vlan_dev_get_stats(dev);
 503         unsigned short veth_TCI;
 504
 505         /* Construct the second two bytes. This field looks something
 506          * like:
 507          * usr_priority: 3 bits  (high bits)
 508          * CFI           1 bit
 509          * VLAN ID       12 bits (low bits)
 510          */
 511         veth_TCI = VLAN_DEV_INFO(dev)->vlan_id;
 512         veth_TCI |= vlan_dev_get_egress_qos_mask(dev, skb);
 513         skb = __vlan_hwaccel_put_tag(skb, veth_TCI);
 514
 515         stats->tx_packets++;
 516         stats->tx_bytes += skb->len;
 517
 518         skb->dev = VLAN_DEV_INFO(dev)->real_dev;
 519         dev_queue_xmit(skb);
 520
 521         return 0;
 522 }
 523
 524 int vlan_dev_change_mtu(struct net_device *dev, int new_mtu)
 525 {
 526         /* TODO: gotta make sure the underlying layer can handle it,
 527          * maybe an IFF_VLAN_CAPABLE flag for devices?
 528          */
 529         if (VLAN_DEV_INFO(dev)->real_dev->mtu < new_mtu)
 530                 return -ERANGE;
 531
 532         dev->mtu = new_mtu;
 533
 534         return 0;
 535 }
 536
 537 int vlan_dev_set_ingress_priority(char *dev_name, __u32 skb_prio, short vlan_prio)
 538 {
 539         struct net_device *dev = dev_get_by_name(dev_name);
 540
 541         if (dev) {
 542                 if (dev->priv_flags & IFF_802_1Q_VLAN) {
 543                         /* see if a priority mapping exists.. */
 544                         VLAN_DEV_INFO(dev)->ingress_priority_map[vlan_prio & 0x7] = skb_prio;
 545                         dev_put(dev);
 546                         return 0;
 547                 }
 548
 549                 dev_put(dev);
 550         }
 551         return -EINVAL;
 552 }
 553
 554 int vlan_dev_set_egress_priority(char *dev_name, __u32 skb_prio, short vlan_prio)
 555 {
 556         struct net_device *dev = dev_get_by_name(dev_name);
 557         struct vlan_priority_tci_mapping *mp = NULL;
 558         struct vlan_priority_tci_mapping *np;
 559
 560         if (dev) {
 561                 if (dev->priv_flags & IFF_802_1Q_VLAN) {
 562                         /* See if a priority mapping exists.. */
 563                         mp = VLAN_DEV_INFO(dev)->egress_priority_map[skb_prio & 0xF];
 564                         while (mp) {
 565                                 if (mp->priority == skb_prio) {
 566                                         mp->vlan_qos = ((vlan_prio << 13) & 0xE000);
 567                                         dev_put(dev);
 568                                         return 0;
 569                                 }
 570                                 mp = mp->next;
 571                         }
 572
 573                         /* Create a new mapping then. */
 574                         mp = VLAN_DEV_INFO(dev)->egress_priority_map[skb_prio & 0xF];
 575                         np = kmalloc(sizeof(struct vlan_priority_tci_mapping), GFP_KERNEL);
 576                         if (np) {
 577                                 np->next = mp;
 578                                 np->priority = skb_prio;
 579                                 np->vlan_qos = ((vlan_prio << 13) & 0xE000);
 580                                 VLAN_DEV_INFO(dev)->egress_priority_map[skb_prio & 0xF] = np;
 581                                 dev_put(dev);
 582                                 return 0;
 583                         } else {
 584                                 dev_put(dev);
 585                                 return -ENOBUFS;
 586                         }
 587                 }
 588                 dev_put(dev);
 589         }
 590         return -EINVAL;
 591 }
 592
 593 /* Flags are defined in the vlan_dev_info class in include/linux/if_vlan.h file. */
 594 int vlan_dev_set_vlan_flag(char *dev_name, __u32 flag, short flag_val)
 595 {
 596         struct net_device *dev = dev_get_by_name(dev_name);
 597
 598         if (dev) {
 599                 if (dev->priv_flags & IFF_802_1Q_VLAN) {
 600                         /* verify flag is supported */
 601                         if (flag == 1) {
 602                                 if (flag_val) {
 603                                         VLAN_DEV_INFO(dev)->flags |= 1;
 604                                 } else {
 605                                         VLAN_DEV_INFO(dev)->flags &= ~1;
 606                                 }
 607                                 dev_put(dev);
 608                                 return 0;
 609                         } else {
 610                                 printk(KERN_ERR  "%s: flag %i is not valid.\n",
 611                                         __FUNCTION__, (int)(flag));
 612                                 dev_put(dev);
 613                                 return -EINVAL;
 614                         }
 615                 } else {
 616                         printk(KERN_ERR
 617                                "%s: %s is not a vlan device, priv_flags: %hX.\n",
 618                                __FUNCTION__, dev->name, dev->priv_flags);
 619                         dev_put(dev);
 620                 }
 621         } else {
 622                 printk(KERN_ERR  "%s: Could not find device: %s\n",
 623                         __FUNCTION__, dev_name);
 624         }
 625
 626         return -EINVAL;
 627 }
 628
 629
 630 int vlan_dev_get_realdev_name(const char *dev_name, char* result)
 631 {
 632         struct net_device *dev = dev_get_by_name(dev_name);
 633         int rv = 0;
 634         if (dev) {
 635                 if (dev->priv_flags & IFF_802_1Q_VLAN) {
 636                         strncpy(result, VLAN_DEV_INFO(dev)->real_dev->name, 23);
 637                         rv = 0;
 638                 } else {
 639                         rv = -EINVAL;
 640                 }
 641                 dev_put(dev);
 642         } else {
 643                 rv = -ENODEV;
 644         }
 645         return rv;
 646 }
 647
 648 int vlan_dev_get_vid(const char *dev_name, unsigned short* result)
 649 {
 650         struct net_device *dev = dev_get_by_name(dev_name);
 651         int rv = 0;
 652         if (dev) {
 653                 if (dev->priv_flags & IFF_802_1Q_VLAN) {
 654                         *result = VLAN_DEV_INFO(dev)->vlan_id;
 655                         rv = 0;
 656                 } else {
 657                         rv = -EINVAL;
 658                 }
 659                 dev_put(dev);
 660         } else {
 661                 rv = -ENODEV;
 662         }
 663         return rv;
 664 }
 665
 666
 667 int vlan_dev_set_mac_address(struct net_device *dev, void *addr_struct_p)
 668 {
 669         struct sockaddr *addr = (struct sockaddr *)(addr_struct_p);
 670         int i;
 671
 672         if (netif_running(dev))
 673                 return -EBUSY;
 674
 675         memcpy(dev->dev_addr, addr->sa_data, dev->addr_len);
 676
 677         printk("%s: Setting MAC address to ", dev->name);
 678         for (i = 0; i < 6; i++)
 679                 printk(" %2.2x", dev->dev_addr[i]);
 680         printk(".\n");
 681
 682         if (memcmp(VLAN_DEV_INFO(dev)->real_dev->dev_addr,
 683                    dev->dev_addr,
 684                    dev->addr_len) != 0) {
 685                 if (!(VLAN_DEV_INFO(dev)->real_dev->flags & IFF_PROMISC)) {
 686                         int flgs = VLAN_DEV_INFO(dev)->real_dev->flags;
 687
 688                         /* Increment our in-use promiscuity counter */
 689                         dev_set_promiscuity(VLAN_DEV_INFO(dev)->real_dev, 1);
 690
 691                         /* Make PROMISC visible to the user. */
 692                         flgs |= IFF_PROMISC;
 693                         printk("VLAN (%s):  Setting underlying device (%s) to promiscious mode.\n",
 694                                dev->name, VLAN_DEV_INFO(dev)->real_dev->name);
 695                         dev_change_flags(VLAN_DEV_INFO(dev)->real_dev, flgs);
 696                 }
 697         } else {
 698                 printk("VLAN (%s):  Underlying device (%s) has same MAC, not checking promiscious mode.\n",
 699                        dev->name, VLAN_DEV_INFO(dev)->real_dev->name);
 700         }
 701
 702         return 0;
 703 }
 704
 705 static inline int vlan_dmi_equals(struct dev_mc_list *dmi1,
 706                                   struct dev_mc_list *dmi2)
 707 {
 708         return ((dmi1->dmi_addrlen == dmi2->dmi_addrlen) &&
 709                 (memcmp(dmi1->dmi_addr, dmi2->dmi_addr, dmi1->dmi_addrlen) == 0));
 710 }
 711
 712 /** dmi is a single entry into a dev_mc_list, a single node.  mc_list is
 713  *  an entire list, and we'll iterate through it.
 714  */
 715 static int vlan_should_add_mc(struct dev_mc_list *dmi, struct dev_mc_list *mc_list)
 716 {
 717         struct dev_mc_list *idmi;
 718
 719         for (idmi = mc_list; idmi != NULL; ) {
 720                 if (vlan_dmi_equals(dmi, idmi)) {
 721                         if (dmi->dmi_users > idmi->dmi_users)
 722                                 return 1;
 723                         else
 724                                 return 0;
 725                 } else {
 726                         idmi = idmi->next;
 727                 }
 728         }
 729
 730         return 1;
 731 }
 732
 733 static inline void vlan_destroy_mc_list(struct dev_mc_list *mc_list)
 734 {
 735         struct dev_mc_list *dmi = mc_list;
 736         struct dev_mc_list *next;
 737
 738         while(dmi) {
 739                 next = dmi->next;
 740                 kfree(dmi);
 741                 dmi = next;
 742         }
 743 }
 744
 745 static void vlan_copy_mc_list(struct dev_mc_list *mc_list, struct vlan_dev_info *vlan_info)
 746 {
 747         struct dev_mc_list *dmi, *new_dmi;
 748
 749         vlan_destroy_mc_list(vlan_info->old_mc_list);
 750         vlan_info->old_mc_list = NULL;
 751
 752         for (dmi = mc_list; dmi != NULL; dmi = dmi->next) {
 753                 new_dmi = kmalloc(sizeof(*new_dmi), GFP_ATOMIC);
 754                 if (new_dmi == NULL) {
 755                         printk(KERN_ERR "vlan: cannot allocate memory. "
 756                                "Multicast may not work properly from now.\n");
 757                         return;
 758                 }
 759
 760                 /* Copy whole structure, then make new 'next' pointer */
 761                 *new_dmi = *dmi;
 762                 new_dmi->next = vlan_info->old_mc_list;
 763                 vlan_info->old_mc_list = new_dmi;
 764         }
 765 }
 766
 767 static void vlan_flush_mc_list(struct net_device *dev)
 768 {
 769         struct dev_mc_list *dmi = dev->mc_list;
 770
 771         while (dmi) {
 772                 printk(KERN_DEBUG "%s: del %.2x:%.2x:%.2x:%.2x:%.2x:%.2x mcast address from vlan interface\n",
 773                        dev->name,
 774                        dmi->dmi_addr[0],
 775                        dmi->dmi_addr[1],
 776                        dmi->dmi_addr[2],
 777                        dmi->dmi_addr[3],
 778                        dmi->dmi_addr[4],
 779                        dmi->dmi_addr[5]);
 780                 dev_mc_delete(dev, dmi->dmi_addr, dmi->dmi_addrlen, 0);
 781                 dmi = dev->mc_list;
 782         }
 783
 784         /* dev->mc_list is NULL by the time we get here. */
 785         vlan_destroy_mc_list(VLAN_DEV_INFO(dev)->old_mc_list);
 786         VLAN_DEV_INFO(dev)->old_mc_list = NULL;
 787 }
 788
 789 int vlan_dev_open(struct net_device *dev)
 790 {
 791         if (!(VLAN_DEV_INFO(dev)->real_dev->flags & IFF_UP))
 792                 return -ENETDOWN;
 793
 794         return 0;
 795 }
 796
 797 int vlan_dev_stop(struct net_device *dev)
 798 {
 799         vlan_flush_mc_list(dev);
 800         return 0;
 801 }
 802
 803 int vlan_dev_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
 804 {
 805         struct net_device *real_dev = VLAN_DEV_INFO(dev)->real_dev;
 806         struct ifreq ifrr;
 807         int err = -EOPNOTSUPP;
 808
 809         strncpy(ifrr.ifr_name, real_dev->name, IFNAMSIZ);
 810         ifrr.ifr_ifru = ifr->ifr_ifru;
 811
 812         switch(cmd) {
 813         case SIOCGMIIPHY:
 814         case SIOCGMIIREG:
 815         case SIOCSMIIREG:
 816                 if (real_dev->do_ioctl && netif_device_present(real_dev))
 817                         err = real_dev->do_ioctl(real_dev, &ifrr, cmd);
 818                 break;
 819
 820         case SIOCETHTOOL:
 821                 err = dev_ethtool(&ifrr);
 822         }
 823
 824         if (!err)
 825                 ifr->ifr_ifru = ifrr.ifr_ifru;
 826
 827         return err;
 828 }
 829
 830 /** Taken from Gleb + Lennert's VLAN code, and modified... */
 831 void vlan_dev_set_multicast_list(struct net_device *vlan_dev)
 832 {
 833         struct dev_mc_list *dmi;
 834         struct net_device *real_dev;
 835         int inc;
 836
 837         if (vlan_dev && (vlan_dev->priv_flags & IFF_802_1Q_VLAN)) {
 838                 /* Then it's a real vlan device, as far as we can tell.. */
 839                 real_dev = VLAN_DEV_INFO(vlan_dev)->real_dev;
 840
 841                 /* compare the current promiscuity to the last promisc we had.. */
 842                 inc = vlan_dev->promiscuity - VLAN_DEV_INFO(vlan_dev)->old_promiscuity;
 843                 if (inc) {
 844                         printk(KERN_INFO "%s: dev_set_promiscuity(master, %d)\n",
 845                                vlan_dev->name, inc);
 846                         dev_set_promiscuity(real_dev, inc); /* found in dev.c */
 847                         VLAN_DEV_INFO(vlan_dev)->old_promiscuity = vlan_dev->promiscuity;
 848                 }
 849
 850                 inc = vlan_dev->allmulti - VLAN_DEV_INFO(vlan_dev)->old_allmulti;
 851                 if (inc) {
 852                         printk(KERN_INFO "%s: dev_set_allmulti(master, %d)\n",
 853                                vlan_dev->name, inc);
 854                         dev_set_allmulti(real_dev, inc); /* dev.c */
 855                         VLAN_DEV_INFO(vlan_dev)->old_allmulti = vlan_dev->allmulti;
 856                 }
 857
 858                 /* looking for addresses to add to master's list */
 859                 for (dmi = vlan_dev->mc_list; dmi != NULL; dmi = dmi->next) {
 860                         if (vlan_should_add_mc(dmi, VLAN_DEV_INFO(vlan_dev)->old_mc_list)) {
 861                                 dev_mc_add(real_dev, dmi->dmi_addr, dmi->dmi_addrlen, 0);
 862                                 printk(KERN_DEBUG "%s: add %.2x:%.2x:%.2x:%.2x:%.2x:%.2x mcast address to master interface\n",
 863                                        vlan_dev->name,
 864                                        dmi->dmi_addr[0],
 865                                        dmi->dmi_addr[1],
 866                                        dmi->dmi_addr[2],
 867                                        dmi->dmi_addr[3],
 868                                        dmi->dmi_addr[4],
 869                                        dmi->dmi_addr[5]);
 870                         }
 871                 }
 872
 873                 /* looking for addresses to delete from master's list */
 874                 for (dmi = VLAN_DEV_INFO(vlan_dev)->old_mc_list; dmi != NULL; dmi = dmi->next) {
 875                         if (vlan_should_add_mc(dmi, vlan_dev->mc_list)) {
 876                                 /* if we think we should add it to the new list, then we should really
 877                                  * delete it from the real list on the underlying device.
 878                                  */
 879                                 dev_mc_delete(real_dev, dmi->dmi_addr, dmi->dmi_addrlen, 0);
 880                                 printk(KERN_DEBUG "%s: del %.2x:%.2x:%.2x:%.2x:%.2x:%.2x mcast address from master interface\n",
 881                                        vlan_dev->name,
 882                                        dmi->dmi_addr[0],
 883                                        dmi->dmi_addr[1],
 884                                        dmi->dmi_addr[2],
 885                                        dmi->dmi_addr[3],
 886                                        dmi->dmi_addr[4],
 887                                        dmi->dmi_addr[5]);
 888                         }
 889                 }
 890
 891                 /* save multicast list */
 892                 vlan_copy_mc_list(vlan_dev->mc_list, VLAN_DEV_INFO(vlan_dev));
 893         }
 894 }