net/8021q/vlan_dev.c

   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: 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, (int)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)
 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         unsigned short 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 the vlan_group_lock until we hold a
 142          * reference to the device (netif_rx does that) or we
 143          * fail.
 144          */
 145
 146         spin_lock_bh(&vlan_group_lock);
 147         skb->dev = __find_vlan_dev(dev, vid);
 148         if (!skb->dev) {
 149                 spin_unlock_bh(&vlan_group_lock);
 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         skb_pull(skb, VLAN_HLEN); /* take off the VLAN header (4 bytes currently) */
 167
 168         /* Ok, lets check to make sure the device (dev) we
 169          * came in on is what this VLAN is attached to.
 170          */
 171
 172         if (dev != VLAN_DEV_INFO(skb->dev)->real_dev) {
 173                 spin_unlock_bh(&vlan_group_lock);
 174
 175 #ifdef VLAN_DEBUG
 176                 printk(VLAN_DBG "%s: dropping skb: %p because came in on wrong device, dev: %s  real_dev: %s, skb_dev: %s\n",
 177                         __FUNCTION__, skb, dev->name,
 178                         VLAN_DEV_INFO(skb->dev)->real_dev->name,
 179                         skb->dev->name);
 180 #endif
 181                 kfree_skb(skb);
 182                 stats->rx_errors++;
 183                 return -1;
 184         }
 185
 186         /*
 187          * Deal with ingress priority mapping.
 188          */
 189         skb->priority = vlan_get_ingress_priority(skb->dev, ntohs(vhdr->h_vlan_TCI));
 190
 191 #ifdef VLAN_DEBUG
 192         printk(VLAN_DBG "%s: priority: %lu  for TCI: %hu (hbo)\n",
 193                 __FUNCTION__, (unsigned long)(skb->priority),
 194                 ntohs(vhdr->h_vlan_TCI));
 195 #endif
 196
 197         /* The ethernet driver already did the pkt_type calculations
 198          * for us...
 199          */
 200         switch (skb->pkt_type) {
 201         case PACKET_BROADCAST: /* Yeah, stats collect these together.. */
 202                 // stats->broadcast ++; // no such counter :-(
 203                 break;
 204
 205         case PACKET_MULTICAST:
 206                 stats->multicast++;
 207                 break;
 208
 209         case PACKET_OTHERHOST:
 210                 /* Our lower layer thinks this is not local, let's make sure.
 211                  * This allows the VLAN to have a different MAC than the underlying
 212                  * device, and still route correctly.
 213                  */
 214                 if (memcmp(skb->mac.ethernet->h_dest, skb->dev->dev_addr, ETH_ALEN) == 0) {
 215                         /* It is for our (changed) MAC-address! */
 216                         skb->pkt_type = PACKET_HOST;
 217                 }
 218                 break;
 219         default:
 220                 break;
 221         };
 222
 223         /*  Was a VLAN packet, grab the encapsulated protocol, which the layer
 224          * three protocols care about.
 225          */
 226         /* proto = get_unaligned(&vhdr->h_vlan_encapsulated_proto); */
 227         proto = vhdr->h_vlan_encapsulated_proto;
 228
 229         skb->protocol = proto;
 230         if (ntohs(proto) >= 1536) {
 231                 /* place it back on the queue to be handled by
 232                  * true layer 3 protocols.
 233                  */
 234
 235                 /* See if we are configured to re-write the VLAN header
 236                  * to make it look like ethernet...
 237                  */
 238                 skb = vlan_check_reorder_header(skb);
 239
 240                 /* Can be null if skb-clone fails when re-ordering */
 241                 if (skb) {
 242                         netif_rx(skb);
 243                 } else {
 244                         /* TODO:  Add a more specific counter here. */
 245                         stats->rx_errors++;
 246                 }
 247                 spin_unlock_bh(&vlan_group_lock);
 248                 return 0;
 249         }
 250
 251         rawp = skb->data;
 252
 253         /*
 254          * This is a magic hack to spot IPX packets. Older Novell breaks
 255          * the protocol design and runs IPX over 802.3 without an 802.2 LLC
 256          * layer. We look for FFFF which isn't a used 802.2 SSAP/DSAP. This
 257          * won't work for fault tolerant netware but does for the rest.
 258          */
 259         if (*(unsigned short *)rawp == 0xFFFF) {
 260                 skb->protocol = __constant_htons(ETH_P_802_3);
 261                 /* place it back on the queue to be handled by true layer 3 protocols.
 262                  */
 263
 264                 /* See if we are configured to re-write the VLAN header
 265                  * to make it look like ethernet...
 266                  */
 267                 skb = vlan_check_reorder_header(skb);
 268
 269                 /* Can be null if skb-clone fails when re-ordering */
 270                 if (skb) {
 271                         netif_rx(skb);
 272                 } else {
 273                         /* TODO:  Add a more specific counter here. */
 274                         stats->rx_errors++;
 275                 }
 276                 spin_unlock_bh(&vlan_group_lock);
 277                 return 0;
 278         }
 279
 280         /*
 281          *      Real 802.2 LLC
 282          */
 283         skb->protocol = __constant_htons(ETH_P_802_2);
 284         /* place it back on the queue to be handled by upper layer protocols.
 285          */
 286
 287         /* See if we are configured to re-write the VLAN header
 288          * to make it look like ethernet...
 289          */
 290         skb = vlan_check_reorder_header(skb);
 291
 292         /* Can be null if skb-clone fails when re-ordering */
 293         if (skb) {
 294                 netif_rx(skb);
 295         } else {
 296                 /* TODO:  Add a more specific counter here. */
 297                 stats->rx_errors++;
 298         }
 299         spin_unlock_bh(&vlan_group_lock);
 300         return 0;
 301 }
 302
 303 static inline unsigned short vlan_dev_get_egress_qos_mask(struct net_device* dev,
 304                                                           struct sk_buff* skb)
 305 {
 306         struct vlan_priority_tci_mapping *mp =
 307                 VLAN_DEV_INFO(dev)->egress_priority_map[(skb->priority & 0xF)];
 308
 309         while (mp) {
 310                 if (mp->priority == skb->priority) {
 311                         return mp->vlan_qos; /* This should already be shifted to mask
 312                                               * correctly with the VLAN's TCI
 313                                               */
 314                 }
 315                 mp = mp->next;
 316         }
 317         return 0;
 318 }
 319
 320 /*
 321  *      Create the VLAN header for an arbitrary protocol layer
 322  *
 323  *      saddr=NULL      means use device source address
 324  *      daddr=NULL      means leave destination address (eg unresolved arp)
 325  *
 326  *  This is called when the SKB is moving down the stack towards the
 327  *  physical devices.
 328  */
 329 int vlan_dev_hard_header(struct sk_buff *skb, struct net_device *dev,
 330                          unsigned short type, void *daddr, void *saddr,
 331                          unsigned len)
 332 {
 333         struct vlan_hdr *vhdr;
 334         unsigned short veth_TCI = 0;
 335         int rc = 0;
 336         int build_vlan_header = 0;
 337         struct net_device *vdev = dev; /* save this for the bottom of the method */
 338
 339 #ifdef VLAN_DEBUG
 340         printk(VLAN_DBG "%s: skb: %p type: %hx len: %x vlan_id: %hx, daddr: %p\n",
 341                 __FUNCTION__, skb, type, len, VLAN_DEV_INFO(dev)->vlan_id, daddr);
 342 #endif
 343
 344         /* build vlan header only if re_order_header flag is NOT set.  This
 345          * fixes some programs that get confused when they see a VLAN device
 346          * sending a frame that is VLAN encoded (the consensus is that the VLAN
 347          * device should look completely like an Ethernet device when the
 348          * REORDER_HEADER flag is set)  The drawback to this is some extra
 349          * header shuffling in the hard_start_xmit.  Users can turn off this
 350          * REORDER behaviour with the vconfig tool.
 351          */
 352         build_vlan_header = ((VLAN_DEV_INFO(dev)->flags & 1) == 0);
 353
 354         if (build_vlan_header) {
 355                 vhdr = (struct vlan_hdr *) skb_push(skb, VLAN_HLEN);
 356
 357                 /* build the four bytes that make this a VLAN header. */
 358
 359                 /* Now, construct the second two bytes. This field looks something
 360                  * like:
 361                  * usr_priority: 3 bits  (high bits)
 362                  * CFI           1 bit
 363                  * VLAN ID       12 bits (low bits)
 364                  *
 365                  */
 366                 veth_TCI = VLAN_DEV_INFO(dev)->vlan_id;
 367                 veth_TCI |= vlan_dev_get_egress_qos_mask(dev, skb);
 368
 369                 vhdr->h_vlan_TCI = htons(veth_TCI);
 370
 371                 /*
 372                  *  Set the protocol type.
 373                  *  For a packet of type ETH_P_802_3 we put the length in here instead.
 374                  *  It is up to the 802.2 layer to carry protocol information.
 375                  */
 376
 377                 if (type != ETH_P_802_3) {
 378                         vhdr->h_vlan_encapsulated_proto = htons(type);
 379                 } else {
 380                         vhdr->h_vlan_encapsulated_proto = htons(len);
 381                 }
 382         }
 383
 384         /* Before delegating work to the lower layer, enter our MAC-address */
 385         if (saddr == NULL)
 386                 saddr = dev->dev_addr;
 387
 388         dev = VLAN_DEV_INFO(dev)->real_dev;
 389
 390         /* MPLS can send us skbuffs w/out enough space.  This check will grow the
 391          * skb if it doesn't have enough headroom.  Not a beautiful solution, so
 392          * I'll tick a counter so that users can know it's happening...  If they
 393          * care...
 394          */
 395
 396         /* NOTE:  This may still break if the underlying device is not the final
 397          * device (and thus there are more headers to add...)  It should work for
 398          * good-ole-ethernet though.
 399          */
 400         if (skb_headroom(skb) < dev->hard_header_len) {
 401                 struct sk_buff *sk_tmp = skb;
 402                 skb = skb_realloc_headroom(sk_tmp, dev->hard_header_len);
 403                 kfree_skb(sk_tmp);
 404                 if (skb == NULL) {
 405                         struct net_device_stats *stats = vlan_dev_get_stats(vdev);
 406                         stats->tx_dropped++;
 407                         return -ENOMEM;
 408                 }
 409                 VLAN_DEV_INFO(vdev)->cnt_inc_headroom_on_tx++;
 410 #ifdef VLAN_DEBUG
 411                 printk(VLAN_DBG "%s: %s: had to grow skb.\n", __FUNCTION__, vdev->name);
 412 #endif
 413         }
 414
 415         if (build_vlan_header) {
 416                 /* Now make the underlying real hard header */
 417                 rc = dev->hard_header(skb, dev, ETH_P_8021Q, daddr, saddr, len + VLAN_HLEN);
 418
 419                 if (rc > 0) {
 420                         rc += VLAN_HLEN;
 421                 } else if (rc < 0) {
 422                         rc -= VLAN_HLEN;
 423                 }
 424         } else {
 425                 /* If here, then we'll just make a normal looking ethernet frame,
 426                  * but, the hard_start_xmit method will insert the tag (it has to
 427                  * be able to do this for bridged and other skbs that don't come
 428                  * down the protocol stack in an orderly manner.
 429                  */
 430                 rc = dev->hard_header(skb, dev, type, daddr, saddr, len);
 431         }
 432
 433         return rc;
 434 }
 435
 436 int vlan_dev_hard_start_xmit(struct sk_buff *skb, struct net_device *dev)
 437 {
 438         struct net_device_stats *stats = vlan_dev_get_stats(dev);
 439         struct vlan_ethhdr *veth = (struct vlan_ethhdr *)(skb->data);
 440
 441         /* Handle non-VLAN frames if they are sent to us, for example by DHCP.
 442          *
 443          * NOTE: THIS ASSUMES DIX ETHERNET, SPECIFICALLY NOT SUPPORTING
 444          * OTHER THINGS LIKE FDDI/TokenRing/802.3 SNAPs...
 445          */
 446
 447         if (veth->h_vlan_proto != __constant_htons(ETH_P_8021Q)) {
 448                 int orig_headroom = skb_headroom(skb);
 449                 unsigned short veth_TCI;
 450
 451                 /* This is not a VLAN frame...but we can fix that! */
 452                 VLAN_DEV_INFO(dev)->cnt_encap_on_xmit++;
 453
 454 #ifdef VLAN_DEBUG
 455                 printk(VLAN_DBG "%s: proto to encap: 0x%hx (hbo)\n",
 456                         __FUNCTION__, htons(veth->h_vlan_proto));
 457 #endif
 458                 /* Construct the second two bytes. This field looks something
 459                  * like:
 460                  * usr_priority: 3 bits  (high bits)
 461                  * CFI           1 bit
 462                  * VLAN ID       12 bits (low bits)
 463                  */
 464                 veth_TCI = VLAN_DEV_INFO(dev)->vlan_id;
 465                 veth_TCI |= vlan_dev_get_egress_qos_mask(dev, skb);
 466
 467                 skb = __vlan_put_tag(skb, veth_TCI);
 468                 if (!skb) {
 469                         stats->tx_dropped++;
 470                         return 0;
 471                 }
 472
 473                 if (orig_headroom < VLAN_HLEN) {
 474                         VLAN_DEV_INFO(dev)->cnt_inc_headroom_on_tx++;
 475                 }
 476         }
 477
 478 #ifdef VLAN_DEBUG
 479         printk(VLAN_DBG "%s: about to send skb: %p to dev: %s\n",
 480                 __FUNCTION__, skb, skb->dev->name);
 481         printk(VLAN_DBG "  %2hx.%2hx.%2hx.%2xh.%2hx.%2hx %2hx.%2hx.%2hx.%2hx.%2hx.%2hx %4hx %4hx %4hx\n",
 482                veth->h_dest[0], veth->h_dest[1], veth->h_dest[2], veth->h_dest[3], veth->h_dest[4], veth->h_dest[5],
 483                veth->h_source[0], veth->h_source[1], veth->h_source[2], veth->h_source[3], veth->h_source[4], veth->h_source[5],
 484                veth->h_vlan_proto, veth->h_vlan_TCI, veth->h_vlan_encapsulated_proto);
 485 #endif
 486
 487         stats->tx_packets++; /* for statics only */
 488         stats->tx_bytes += skb->len;
 489
 490         skb->dev = VLAN_DEV_INFO(dev)->real_dev;
 491         dev_queue_xmit(skb);
 492
 493         return 0;
 494 }
 495
 496 int vlan_dev_hwaccel_hard_start_xmit(struct sk_buff *skb, struct net_device *dev)
 497 {
 498         struct net_device_stats *stats = vlan_dev_get_stats(dev);
 499         unsigned short veth_TCI;
 500
 501         /* Construct the second two bytes. This field looks something
 502          * like:
 503          * usr_priority: 3 bits  (high bits)
 504          * CFI           1 bit
 505          * VLAN ID       12 bits (low bits)
 506          */
 507         veth_TCI = VLAN_DEV_INFO(dev)->vlan_id;
 508         veth_TCI |= vlan_dev_get_egress_qos_mask(dev, skb);
 509         skb = __vlan_hwaccel_put_tag(skb, veth_TCI);
 510
 511         stats->tx_packets++;
 512         stats->tx_bytes += skb->len;
 513
 514         skb->dev = VLAN_DEV_INFO(dev)->real_dev;
 515         dev_queue_xmit(skb);
 516
 517         return 0;
 518 }
 519
 520 int vlan_dev_change_mtu(struct net_device *dev, int new_mtu)
 521 {
 522         /* TODO: gotta make sure the underlying layer can handle it,
 523          * maybe an IFF_VLAN_CAPABLE flag for devices?
 524          */
 525         if (VLAN_DEV_INFO(dev)->real_dev->mtu < new_mtu)
 526                 return -ERANGE;
 527
 528         dev->mtu = new_mtu;
 529
 530         return new_mtu;
 531 }
 532
 533 int vlan_dev_set_ingress_priority(char *dev_name, __u32 skb_prio, short vlan_prio)
 534 {
 535         struct net_device *dev = dev_get_by_name(dev_name);
 536
 537         if (dev) {
 538                 if (dev->priv_flags & IFF_802_1Q_VLAN) {
 539                         /* see if a priority mapping exists.. */
 540                         VLAN_DEV_INFO(dev)->ingress_priority_map[vlan_prio & 0x7] = skb_prio;
 541                         dev_put(dev);
 542                         return 0;
 543                 }
 544
 545                 dev_put(dev);
 546         }
 547         return -EINVAL;
 548 }
 549
 550 int vlan_dev_set_egress_priority(char *dev_name, __u32 skb_prio, short vlan_prio)
 551 {
 552         struct net_device *dev = dev_get_by_name(dev_name);
 553         struct vlan_priority_tci_mapping *mp = NULL;
 554         struct vlan_priority_tci_mapping *np;
 555
 556         if (dev) {
 557                 if (dev->priv_flags & IFF_802_1Q_VLAN) {
 558                         /* See if a priority mapping exists.. */
 559                         mp = VLAN_DEV_INFO(dev)->egress_priority_map[skb_prio & 0xF];
 560                         while (mp) {
 561                                 if (mp->priority == skb_prio) {
 562                                         mp->vlan_qos = ((vlan_prio << 13) & 0xE000);
 563                                         dev_put(dev);
 564                                         return 0;
 565                                 }
 566                                 mp = mp->next;
 567                         }
 568
 569                         /* Create a new mapping then. */
 570                         mp = VLAN_DEV_INFO(dev)->egress_priority_map[skb_prio & 0xF];
 571                         np = kmalloc(sizeof(struct vlan_priority_tci_mapping), GFP_KERNEL);
 572                         if (np) {
 573                                 np->next = mp;
 574                                 np->priority = skb_prio;
 575                                 np->vlan_qos = ((vlan_prio << 13) & 0xE000);
 576                                 VLAN_DEV_INFO(dev)->egress_priority_map[skb_prio & 0xF] = np;
 577                                 dev_put(dev);
 578                                 return 0;
 579                         } else {
 580                                 dev_put(dev);
 581                                 return -ENOBUFS;
 582                         }
 583                 }
 584                 dev_put(dev);
 585         }
 586         return -EINVAL;
 587 }
 588
 589 /* Flags are defined in the vlan_dev_info class in include/linux/if_vlan.h file. */
 590 int vlan_dev_set_vlan_flag(char *dev_name, __u32 flag, short flag_val)
 591 {
 592         struct net_device *dev = dev_get_by_name(dev_name);
 593
 594         if (dev) {
 595                 if (dev->priv_flags & IFF_802_1Q_VLAN) {
 596                         /* verify flag is supported */
 597                         if (flag == 1) {
 598                                 if (flag_val) {
 599                                         VLAN_DEV_INFO(dev)->flags |= 1;
 600                                 } else {
 601                                         VLAN_DEV_INFO(dev)->flags &= ~1;
 602                                 }
 603                                 dev_put(dev);
 604                                 return 0;
 605                         } else {
 606                                 printk(KERN_ERR  "%s: flag %i is not valid.\n",
 607                                         __FUNCTION__, (int)(flag));
 608                                 dev_put(dev);
 609                                 return -EINVAL;
 610                         }
 611                 } else {
 612                         printk(KERN_ERR
 613                                "%s: %s is not a vlan device, priv_flags: %hX.\n",
 614                                __FUNCTION__, dev->name, dev->priv_flags);
 615                         dev_put(dev);
 616                 }
 617         } else {
 618                 printk(KERN_ERR  "%s: Could not find device: %s\n",
 619                         __FUNCTION__, dev_name);
 620         }
 621
 622         return -EINVAL;
 623 }
 624
 625 int vlan_dev_set_mac_address(struct net_device *dev, void *addr_struct_p)
 626 {
 627         struct sockaddr *addr = (struct sockaddr *)(addr_struct_p);
 628         int i;
 629
 630         if (netif_running(dev))
 631                 return -EBUSY;
 632
 633         memcpy(dev->dev_addr, addr->sa_data, dev->addr_len);
 634
 635         printk("%s: Setting MAC address to ", dev->name);
 636         for (i = 0; i < 6; i++)
 637                 printk(" %2.2x", dev->dev_addr[i]);
 638         printk(".\n");
 639
 640         if (memcmp(VLAN_DEV_INFO(dev)->real_dev->dev_addr,
 641                    dev->dev_addr,
 642                    dev->addr_len) != 0) {
 643                 if (!(VLAN_DEV_INFO(dev)->real_dev->flags & IFF_PROMISC)) {
 644                         int flgs = VLAN_DEV_INFO(dev)->real_dev->flags;
 645
 646                         /* Increment our in-use promiscuity counter */
 647                         dev_set_promiscuity(VLAN_DEV_INFO(dev)->real_dev, 1);
 648
 649                         /* Make PROMISC visible to the user. */
 650                         flgs |= IFF_PROMISC;
 651                         printk("VLAN (%s):  Setting underlying device (%s) to promiscious mode.\n",
 652                                dev->name, VLAN_DEV_INFO(dev)->real_dev->name);
 653                         dev_change_flags(VLAN_DEV_INFO(dev)->real_dev, flgs);
 654                 }
 655         } else {
 656                 printk("VLAN (%s):  Underlying device (%s) has same MAC, not checking promiscious mode.\n",
 657                        dev->name, VLAN_DEV_INFO(dev)->real_dev->name);
 658         }
 659
 660         return 0;
 661 }
 662
 663 static inline int vlan_dmi_equals(struct dev_mc_list *dmi1,
 664                                   struct dev_mc_list *dmi2)
 665 {
 666         return ((dmi1->dmi_addrlen == dmi2->dmi_addrlen) &&
 667                 (memcmp(dmi1->dmi_addr, dmi2->dmi_addr, dmi1->dmi_addrlen) == 0));
 668 }
 669
 670 /** dmi is a single entry into a dev_mc_list, a single node.  mc_list is
 671  *  an entire list, and we'll iterate through it.
 672  */
 673 static int vlan_should_add_mc(struct dev_mc_list *dmi, struct dev_mc_list *mc_list)
 674 {
 675         struct dev_mc_list *idmi;
 676
 677         for (idmi = mc_list; idmi != NULL; ) {
 678                 if (vlan_dmi_equals(dmi, idmi)) {
 679                         if (dmi->dmi_users > idmi->dmi_users)
 680                                 return 1;
 681                         else
 682                                 return 0;
 683                 } else {
 684                         idmi = idmi->next;
 685                 }
 686         }
 687
 688         return 1;
 689 }
 690
 691 static inline void vlan_destroy_mc_list(struct dev_mc_list *mc_list)
 692 {
 693         struct dev_mc_list *dmi = mc_list;
 694         struct dev_mc_list *next;
 695
 696         while(dmi) {
 697                 next = dmi->next;
 698                 kfree(dmi);
 699                 dmi = next;
 700         }
 701 }
 702
 703 static void vlan_copy_mc_list(struct dev_mc_list *mc_list, struct vlan_dev_info *vlan_info)
 704 {
 705         struct dev_mc_list *dmi, *new_dmi;
 706
 707         vlan_destroy_mc_list(vlan_info->old_mc_list);
 708         vlan_info->old_mc_list = NULL;
 709
 710         for (dmi = mc_list; dmi != NULL; dmi = dmi->next) {
 711                 new_dmi = kmalloc(sizeof(*new_dmi), GFP_ATOMIC);
 712                 if (new_dmi == NULL) {
 713                         printk(KERN_ERR "vlan: cannot allocate memory. "
 714                                "Multicast may not work properly from now.\n");
 715                         return;
 716                 }
 717
 718                 /* Copy whole structure, then make new 'next' pointer */
 719                 *new_dmi = *dmi;
 720                 new_dmi->next = vlan_info->old_mc_list;
 721                 vlan_info->old_mc_list = new_dmi;
 722         }
 723 }
 724
 725 static void vlan_flush_mc_list(struct net_device *dev)
 726 {
 727         struct dev_mc_list *dmi = dev->mc_list;
 728
 729         while (dmi) {
 730                 dev_mc_delete(dev, dmi->dmi_addr, dmi->dmi_addrlen, 0);
 731                 printk(KERN_DEBUG "%s: del %.2x:%.2x:%.2x:%.2x:%.2x:%.2x mcast address from vlan interface\n",
 732                        dev->name,
 733                        dmi->dmi_addr[0],
 734                        dmi->dmi_addr[1],
 735                        dmi->dmi_addr[2],
 736                        dmi->dmi_addr[3],
 737                        dmi->dmi_addr[4],
 738                        dmi->dmi_addr[5]);
 739                 dmi = dev->mc_list;
 740         }
 741
 742         /* dev->mc_list is NULL by the time we get here. */
 743         vlan_destroy_mc_list(VLAN_DEV_INFO(dev)->old_mc_list);
 744         VLAN_DEV_INFO(dev)->old_mc_list = NULL;
 745 }
 746
 747 int vlan_dev_open(struct net_device *dev)
 748 {
 749         if (!(VLAN_DEV_INFO(dev)->real_dev->flags & IFF_UP))
 750                 return -ENETDOWN;
 751
 752         return 0;
 753 }
 754
 755 int vlan_dev_stop(struct net_device *dev)
 756 {
 757         vlan_flush_mc_list(dev);
 758         return 0;
 759 }
 760 /** Taken from Gleb + Lennert's VLAN code, and modified... */
 761 void vlan_dev_set_multicast_list(struct net_device *vlan_dev)
 762 {
 763         struct dev_mc_list *dmi;
 764         struct net_device *real_dev;
 765         int inc;
 766
 767         if (vlan_dev && (vlan_dev->priv_flags & IFF_802_1Q_VLAN)) {
 768                 /* Then it's a real vlan device, as far as we can tell.. */
 769                 real_dev = VLAN_DEV_INFO(vlan_dev)->real_dev;
 770
 771                 /* compare the current promiscuity to the last promisc we had.. */
 772                 inc = vlan_dev->promiscuity - VLAN_DEV_INFO(vlan_dev)->old_promiscuity;
 773                 if (inc) {
 774                         printk(KERN_INFO "%s: dev_set_promiscuity(master, %d)\n",
 775                                vlan_dev->name, inc);
 776                         dev_set_promiscuity(real_dev, inc); /* found in dev.c */
 777                         VLAN_DEV_INFO(vlan_dev)->old_promiscuity = vlan_dev->promiscuity;
 778                 }
 779
 780                 inc = vlan_dev->allmulti - VLAN_DEV_INFO(vlan_dev)->old_allmulti;
 781                 if (inc) {
 782                         printk(KERN_INFO "%s: dev_set_allmulti(master, %d)\n",
 783                                vlan_dev->name, inc);
 784                         dev_set_allmulti(real_dev, inc); /* dev.c */
 785                         VLAN_DEV_INFO(vlan_dev)->old_allmulti = vlan_dev->allmulti;
 786                 }
 787
 788                 /* looking for addresses to add to master's list */
 789                 for (dmi = vlan_dev->mc_list; dmi != NULL; dmi = dmi->next) {
 790                         if (vlan_should_add_mc(dmi, VLAN_DEV_INFO(vlan_dev)->old_mc_list)) {
 791                                 dev_mc_add(real_dev, dmi->dmi_addr, dmi->dmi_addrlen, 0);
 792                                 printk(KERN_DEBUG "%s: add %.2x:%.2x:%.2x:%.2x:%.2x:%.2x mcast address to master interface\n",
 793                                        vlan_dev->name,
 794                                        dmi->dmi_addr[0],
 795                                        dmi->dmi_addr[1],
 796                                        dmi->dmi_addr[2],
 797                                        dmi->dmi_addr[3],
 798                                        dmi->dmi_addr[4],
 799                                        dmi->dmi_addr[5]);
 800                         }
 801                 }
 802
 803                 /* looking for addresses to delete from master's list */
 804                 for (dmi = VLAN_DEV_INFO(vlan_dev)->old_mc_list; dmi != NULL; dmi = dmi->next) {
 805                         if (vlan_should_add_mc(dmi, vlan_dev->mc_list)) {
 806                                 /* if we think we should add it to the new list, then we should really
 807                                  * delete it from the real list on the underlying device.
 808                                  */
 809                                 dev_mc_delete(real_dev, dmi->dmi_addr, dmi->dmi_addrlen, 0);
 810                                 printk(KERN_DEBUG "%s: del %.2x:%.2x:%.2x:%.2x:%.2x:%.2x mcast address from master interface\n",
 811                                        vlan_dev->name,
 812                                        dmi->dmi_addr[0],
 813                                        dmi->dmi_addr[1],
 814                                        dmi->dmi_addr[2],
 815                                        dmi->dmi_addr[3],
 816                                        dmi->dmi_addr[4],
 817                                        dmi->dmi_addr[5]);
 818                         }
 819                 }
 820
 821                 /* save multicast list */
 822                 vlan_copy_mc_list(vlan_dev->mc_list, VLAN_DEV_INFO(vlan_dev));
 823         }
 824 }