net/atm/br2684.c

   1 /*
   2  * Ethernet netdevice using ATM AAL5 as underlying carrier
   3  * (RFC1483 obsoleted by RFC2684) for Linux
   4  *
   5  * Authors: Marcell GAL, 2000, XDSL Ltd, Hungary
   6  *          Eric Kinzie, 2006-2007, US Naval Research Laboratory
   7  */
   8
   9 #define pr_fmt(fmt) KBUILD_MODNAME ":%s: " fmt, __func__
  10
  11 #include <linux/module.h>
  12 #include <linux/init.h>
  13 #include <linux/kernel.h>
  14 #include <linux/list.h>
  15 #include <linux/netdevice.h>
  16 #include <linux/skbuff.h>
  17 #include <linux/etherdevice.h>
  18 #include <linux/rtnetlink.h>
  19 #include <linux/ip.h>
  20 #include <linux/uaccess.h>
  21 #include <linux/slab.h>
  22 #include <net/arp.h>
  23 #include <linux/atm.h>
  24 #include <linux/atmdev.h>
  25 #include <linux/capability.h>
  26 #include <linux/seq_file.h>
  27
  28 #include <linux/atmbr2684.h>
  29
  30 #include "common.h"
  31
  32 static void skb_debug(const struct sk_buff *skb)
  33 {
  34 #ifdef SKB_DEBUG
  35 #define NUM2PRINT 50
  36         print_hex_dump(KERN_DEBUG, "br2684: skb: ", DUMP_OFFSET,
  37                        16, 1, skb->data, min(NUM2PRINT, skb->len), true);
  38 #endif
  39 }
  40
  41 #define BR2684_ETHERTYPE_LEN    2
  42 #define BR2684_PAD_LEN          2
  43
  44 #define LLC             0xaa, 0xaa, 0x03
  45 #define SNAP_BRIDGED    0x00, 0x80, 0xc2
  46 #define SNAP_ROUTED     0x00, 0x00, 0x00
  47 #define PID_ETHERNET    0x00, 0x07
  48 #define ETHERTYPE_IPV4  0x08, 0x00
  49 #define ETHERTYPE_IPV6  0x86, 0xdd
  50 #define PAD_BRIDGED     0x00, 0x00
  51
  52 static const unsigned char ethertype_ipv4[] = { ETHERTYPE_IPV4 };
  53 static const unsigned char ethertype_ipv6[] = { ETHERTYPE_IPV6 };
  54 static const unsigned char llc_oui_pid_pad[] =
  55                         { LLC, SNAP_BRIDGED, PID_ETHERNET, PAD_BRIDGED };
  56 static const unsigned char llc_oui_ipv4[] = { LLC, SNAP_ROUTED, ETHERTYPE_IPV4 };
  57 static const unsigned char llc_oui_ipv6[] = { LLC, SNAP_ROUTED, ETHERTYPE_IPV6 };
  58
  59 enum br2684_encaps {
  60         e_vc = BR2684_ENCAPS_VC,
  61         e_llc = BR2684_ENCAPS_LLC,
  62 };
  63
  64 struct br2684_vcc {
  65         struct atm_vcc *atmvcc;
  66         struct net_device *device;
  67         /* keep old push, pop functions for chaining */
  68         void (*old_push)(struct atm_vcc *vcc, struct sk_buff *skb);
  69         void (*old_pop)(struct atm_vcc *vcc, struct sk_buff *skb);
  70         enum br2684_encaps encaps;
  71         struct list_head brvccs;
  72 #ifdef CONFIG_ATM_BR2684_IPFILTER
  73         struct br2684_filter filter;
  74 #endif /* CONFIG_ATM_BR2684_IPFILTER */
  75         unsigned copies_needed, copies_failed;
  76 };
  77
  78 struct br2684_dev {
  79         struct net_device *net_dev;
  80         struct list_head br2684_devs;
  81         int number;
  82         struct list_head brvccs;        /* one device <=> one vcc (before xmas) */
  83         int mac_was_set;
  84         enum br2684_payload payload;
  85 };
  86
  87 /*
  88  * This lock should be held for writing any time the list of devices or
  89  * their attached vcc's could be altered.  It should be held for reading
  90  * any time these are being queried.  Note that we sometimes need to
  91  * do read-locking under interrupt context, so write locking must block
  92  * the current CPU's interrupts
  93  */
  94 static DEFINE_RWLOCK(devs_lock);
  95
  96 static LIST_HEAD(br2684_devs);
  97
  98 static inline struct br2684_dev *BRPRIV(const struct net_device *net_dev)
  99 {
 100         return netdev_priv(net_dev);
 101 }
 102
 103 static inline struct net_device *list_entry_brdev(const struct list_head *le)
 104 {
 105         return list_entry(le, struct br2684_dev, br2684_devs)->net_dev;
 106 }
 107
 108 static inline struct br2684_vcc *BR2684_VCC(const struct atm_vcc *atmvcc)
 109 {
 110         return (struct br2684_vcc *)(atmvcc->user_back);
 111 }
 112
 113 static inline struct br2684_vcc *list_entry_brvcc(const struct list_head *le)
 114 {
 115         return list_entry(le, struct br2684_vcc, brvccs);
 116 }
 117
 118 /* Caller should hold read_lock(&devs_lock) */
 119 static struct net_device *br2684_find_dev(const struct br2684_if_spec *s)
 120 {
 121         struct list_head *lh;
 122         struct net_device *net_dev;
 123         switch (s->method) {
 124         case BR2684_FIND_BYNUM:
 125                 list_for_each(lh, &br2684_devs) {
 126                         net_dev = list_entry_brdev(lh);
 127                         if (BRPRIV(net_dev)->number == s->spec.devnum)
 128                                 return net_dev;
 129                 }
 130                 break;
 131         case BR2684_FIND_BYIFNAME:
 132                 list_for_each(lh, &br2684_devs) {
 133                         net_dev = list_entry_brdev(lh);
 134                         if (!strncmp(net_dev->name, s->spec.ifname, IFNAMSIZ))
 135                                 return net_dev;
 136                 }
 137                 break;
 138         }
 139         return NULL;
 140 }
 141
 142 static int atm_dev_event(struct notifier_block *this, unsigned long event,
 143                  void *arg)
 144 {
 145         struct atm_dev *atm_dev = arg;
 146         struct list_head *lh;
 147         struct net_device *net_dev;
 148         struct br2684_vcc *brvcc;
 149         struct atm_vcc *atm_vcc;
 150         unsigned long flags;
 151
 152         pr_debug("event=%ld dev=%p\n", event, atm_dev);
 153
 154         read_lock_irqsave(&devs_lock, flags);
 155         list_for_each(lh, &br2684_devs) {
 156                 net_dev = list_entry_brdev(lh);
 157
 158                 list_for_each_entry(brvcc, &BRPRIV(net_dev)->brvccs, brvccs) {
 159                         atm_vcc = brvcc->atmvcc;
 160                         if (atm_vcc && brvcc->atmvcc->dev == atm_dev) {
 161
 162                                 if (atm_vcc->dev->signal == ATM_PHY_SIG_LOST)
 163                                         netif_carrier_off(net_dev);
 164                                 else
 165                                         netif_carrier_on(net_dev);
 166
 167                         }
 168                 }
 169         }
 170         read_unlock_irqrestore(&devs_lock, flags);
 171
 172         return NOTIFY_DONE;
 173 }
 174
 175 static struct notifier_block atm_dev_notifier = {
 176         .notifier_call = atm_dev_event,
 177 };
 178
 179 /* chained vcc->pop function.  Check if we should wake the netif_queue */
 180 static void br2684_pop(struct atm_vcc *vcc, struct sk_buff *skb)
 181 {
 182         struct br2684_vcc *brvcc = BR2684_VCC(vcc);
 183         struct net_device *net_dev = skb->dev;
 184
 185         pr_debug("(vcc %p ; net_dev %p )\n", vcc, net_dev);
 186         brvcc->old_pop(vcc, skb);
 187
 188         if (!net_dev)
 189                 return;
 190
 191         if (atm_may_send(vcc, 0))
 192                 netif_wake_queue(net_dev);
 193
 194 }
 195 /*
 196  * Send a packet out a particular vcc.  Not to useful right now, but paves
 197  * the way for multiple vcc's per itf.  Returns true if we can send,
 198  * otherwise false
 199  */
 200 static int br2684_xmit_vcc(struct sk_buff *skb, struct net_device *dev,
 201                            struct br2684_vcc *brvcc)
 202 {
 203         struct br2684_dev *brdev = BRPRIV(dev);
 204         struct atm_vcc *atmvcc;
 205         int minheadroom = (brvcc->encaps == e_llc) ? 10 : 2;
 206
 207         if (skb_headroom(skb) < minheadroom) {
 208                 struct sk_buff *skb2 = skb_realloc_headroom(skb, minheadroom);
 209                 brvcc->copies_needed++;
 210                 dev_kfree_skb(skb);
 211                 if (skb2 == NULL) {
 212                         brvcc->copies_failed++;
 213                         return 0;
 214                 }
 215                 skb = skb2;
 216         }
 217
 218         if (brvcc->encaps == e_llc) {
 219                 if (brdev->payload == p_bridged) {
 220                         skb_push(skb, sizeof(llc_oui_pid_pad));
 221                         skb_copy_to_linear_data(skb, llc_oui_pid_pad,
 222                                                 sizeof(llc_oui_pid_pad));
 223                 } else if (brdev->payload == p_routed) {
 224                         unsigned short prot = ntohs(skb->protocol);
 225
 226                         skb_push(skb, sizeof(llc_oui_ipv4));
 227                         switch (prot) {
 228                         case ETH_P_IP:
 229                                 skb_copy_to_linear_data(skb, llc_oui_ipv4,
 230                                                         sizeof(llc_oui_ipv4));
 231                                 break;
 232                         case ETH_P_IPV6:
 233                                 skb_copy_to_linear_data(skb, llc_oui_ipv6,
 234                                                         sizeof(llc_oui_ipv6));
 235                                 break;
 236                         default:
 237                                 dev_kfree_skb(skb);
 238                                 return 0;
 239                         }
 240                 }
 241         } else { /* e_vc */
 242                 if (brdev->payload == p_bridged) {
 243                         skb_push(skb, 2);
 244                         memset(skb->data, 0, 2);
 245                 }
 246         }
 247         skb_debug(skb);
 248
 249         ATM_SKB(skb)->vcc = atmvcc = brvcc->atmvcc;
 250         pr_debug("atm_skb(%p)->vcc(%p)->dev(%p)\n", skb, atmvcc, atmvcc->dev);
 251         atomic_add(skb->truesize, &sk_atm(atmvcc)->sk_wmem_alloc);
 252         ATM_SKB(skb)->atm_options = atmvcc->atm_options;
 253         dev->stats.tx_packets++;
 254         dev->stats.tx_bytes += skb->len;
 255         atmvcc->send(atmvcc, skb);
 256
 257         if (!atm_may_send(atmvcc, 0)) {
 258                 netif_stop_queue(brvcc->device);
 259                 /*check for race with br2684_pop*/
 260                 if (atm_may_send(atmvcc, 0))
 261                         netif_start_queue(brvcc->device);
 262         }
 263
 264         return 1;
 265 }
 266
 267 static inline struct br2684_vcc *pick_outgoing_vcc(const struct sk_buff *skb,
 268                                                    const struct br2684_dev *brdev)
 269 {
 270         return list_empty(&brdev->brvccs) ? NULL : list_entry_brvcc(brdev->brvccs.next);        /* 1 vcc/dev right now */
 271 }
 272
 273 static netdev_tx_t br2684_start_xmit(struct sk_buff *skb,
 274                                      struct net_device *dev)
 275 {
 276         struct br2684_dev *brdev = BRPRIV(dev);
 277         struct br2684_vcc *brvcc;
 278
 279         pr_debug("skb_dst(skb)=%p\n", skb_dst(skb));
 280         read_lock(&devs_lock);
 281         brvcc = pick_outgoing_vcc(skb, brdev);
 282         if (brvcc == NULL) {
 283                 pr_debug("no vcc attached to dev %s\n", dev->name);
 284                 dev->stats.tx_errors++;
 285                 dev->stats.tx_carrier_errors++;
 286                 /* netif_stop_queue(dev); */
 287                 dev_kfree_skb(skb);
 288                 read_unlock(&devs_lock);
 289                 return NETDEV_TX_OK;
 290         }
 291         if (!br2684_xmit_vcc(skb, dev, brvcc)) {
 292                 /*
 293                  * We should probably use netif_*_queue() here, but that
 294                  * involves added complication.  We need to walk before
 295                  * we can run.
 296                  *
 297                  * Don't free here! this pointer might be no longer valid!
 298                  */
 299                 dev->stats.tx_errors++;
 300                 dev->stats.tx_fifo_errors++;
 301         }
 302         read_unlock(&devs_lock);
 303         return NETDEV_TX_OK;
 304 }
 305
 306 /*
 307  * We remember when the MAC gets set, so we don't override it later with
 308  * the ESI of the ATM card of the first VC
 309  */
 310 static int br2684_mac_addr(struct net_device *dev, void *p)
 311 {
 312         int err = eth_mac_addr(dev, p);
 313         if (!err)
 314                 BRPRIV(dev)->mac_was_set = 1;
 315         return err;
 316 }
 317
 318 #ifdef CONFIG_ATM_BR2684_IPFILTER
 319 /* this IOCTL is experimental. */
 320 static int br2684_setfilt(struct atm_vcc *atmvcc, void __user * arg)
 321 {
 322         struct br2684_vcc *brvcc;
 323         struct br2684_filter_set fs;
 324
 325         if (copy_from_user(&fs, arg, sizeof fs))
 326                 return -EFAULT;
 327         if (fs.ifspec.method != BR2684_FIND_BYNOTHING) {
 328                 /*
 329                  * This is really a per-vcc thing, but we can also search
 330                  * by device.
 331                  */
 332                 struct br2684_dev *brdev;
 333                 read_lock(&devs_lock);
 334                 brdev = BRPRIV(br2684_find_dev(&fs.ifspec));
 335                 if (brdev == NULL || list_empty(&brdev->brvccs) ||
 336                     brdev->brvccs.next != brdev->brvccs.prev)   /* >1 VCC */
 337                         brvcc = NULL;
 338                 else
 339                         brvcc = list_entry_brvcc(brdev->brvccs.next);
 340                 read_unlock(&devs_lock);
 341                 if (brvcc == NULL)
 342                         return -ESRCH;
 343         } else
 344                 brvcc = BR2684_VCC(atmvcc);
 345         memcpy(&brvcc->filter, &fs.filter, sizeof(brvcc->filter));
 346         return 0;
 347 }
 348
 349 /* Returns 1 if packet should be dropped */
 350 static inline int
 351 packet_fails_filter(__be16 type, struct br2684_vcc *brvcc, struct sk_buff *skb)
 352 {
 353         if (brvcc->filter.netmask == 0)
 354                 return 0;       /* no filter in place */
 355         if (type == htons(ETH_P_IP) &&
 356             (((struct iphdr *)(skb->data))->daddr & brvcc->filter.
 357              netmask) == brvcc->filter.prefix)
 358                 return 0;
 359         if (type == htons(ETH_P_ARP))
 360                 return 0;
 361         /*
 362          * TODO: we should probably filter ARPs too.. don't want to have
 363          * them returning values that don't make sense, or is that ok?
 364          */
 365         return 1;               /* drop */
 366 }
 367 #endif /* CONFIG_ATM_BR2684_IPFILTER */
 368
 369 static void br2684_close_vcc(struct br2684_vcc *brvcc)
 370 {
 371         pr_debug("removing VCC %p from dev %p\n", brvcc, brvcc->device);
 372         write_lock_irq(&devs_lock);
 373         list_del(&brvcc->brvccs);
 374         write_unlock_irq(&devs_lock);
 375         brvcc->atmvcc->user_back = NULL;        /* what about vcc->recvq ??? */
 376         brvcc->old_push(brvcc->atmvcc, NULL);   /* pass on the bad news */
 377         kfree(brvcc);
 378         module_put(THIS_MODULE);
 379 }
 380
 381 /* when AAL5 PDU comes in: */
 382 static void br2684_push(struct atm_vcc *atmvcc, struct sk_buff *skb)
 383 {
 384         struct br2684_vcc *brvcc = BR2684_VCC(atmvcc);
 385         struct net_device *net_dev = brvcc->device;
 386         struct br2684_dev *brdev = BRPRIV(net_dev);
 387
 388         pr_debug("\n");
 389
 390         if (unlikely(skb == NULL)) {
 391                 /* skb==NULL means VCC is being destroyed */
 392                 br2684_close_vcc(brvcc);
 393                 if (list_empty(&brdev->brvccs)) {
 394                         write_lock_irq(&devs_lock);
 395                         list_del(&brdev->br2684_devs);
 396                         write_unlock_irq(&devs_lock);
 397                         unregister_netdev(net_dev);
 398                         free_netdev(net_dev);
 399                 }
 400                 return;
 401         }
 402
 403         skb_debug(skb);
 404         atm_return(atmvcc, skb->truesize);
 405         pr_debug("skb from brdev %p\n", brdev);
 406         if (brvcc->encaps == e_llc) {
 407
 408                 if (skb->len > 7 && skb->data[7] == 0x01)
 409                         __skb_trim(skb, skb->len - 4);
 410
 411                 /* accept packets that have "ipv[46]" in the snap header */
 412                 if ((skb->len >= (sizeof(llc_oui_ipv4))) &&
 413                     (memcmp(skb->data, llc_oui_ipv4,
 414                             sizeof(llc_oui_ipv4) - BR2684_ETHERTYPE_LEN) == 0)) {
 415                         if (memcmp(skb->data + 6, ethertype_ipv6,
 416                                    sizeof(ethertype_ipv6)) == 0)
 417                                 skb->protocol = htons(ETH_P_IPV6);
 418                         else if (memcmp(skb->data + 6, ethertype_ipv4,
 419                                         sizeof(ethertype_ipv4)) == 0)
 420                                 skb->protocol = htons(ETH_P_IP);
 421                         else
 422                                 goto error;
 423                         skb_pull(skb, sizeof(llc_oui_ipv4));
 424                         skb_reset_network_header(skb);
 425                         skb->pkt_type = PACKET_HOST;
 426                 /*
 427                  * Let us waste some time for checking the encapsulation.
 428                  * Note, that only 7 char is checked so frames with a valid FCS
 429                  * are also accepted (but FCS is not checked of course).
 430                  */
 431                 } else if ((skb->len >= sizeof(llc_oui_pid_pad)) &&
 432                            (memcmp(skb->data, llc_oui_pid_pad, 7) == 0)) {
 433                         skb_pull(skb, sizeof(llc_oui_pid_pad));
 434                         skb->protocol = eth_type_trans(skb, net_dev);
 435                 } else
 436                         goto error;
 437
 438         } else { /* e_vc */
 439                 if (brdev->payload == p_routed) {
 440                         struct iphdr *iph;
 441
 442                         skb_reset_network_header(skb);
 443                         iph = ip_hdr(skb);
 444                         if (iph->version == 4)
 445                                 skb->protocol = htons(ETH_P_IP);
 446                         else if (iph->version == 6)
 447                                 skb->protocol = htons(ETH_P_IPV6);
 448                         else
 449                                 goto error;
 450                         skb->pkt_type = PACKET_HOST;
 451                 } else { /* p_bridged */
 452                         /* first 2 chars should be 0 */
 453                         if (*((u16 *) (skb->data)) != 0)
 454                                 goto error;
 455                         skb_pull(skb, BR2684_PAD_LEN);
 456                         skb->protocol = eth_type_trans(skb, net_dev);
 457                 }
 458         }
 459
 460 #ifdef CONFIG_ATM_BR2684_IPFILTER
 461         if (unlikely(packet_fails_filter(skb->protocol, brvcc, skb)))
 462                 goto dropped;
 463 #endif /* CONFIG_ATM_BR2684_IPFILTER */
 464         skb->dev = net_dev;
 465         ATM_SKB(skb)->vcc = atmvcc;     /* needed ? */
 466         pr_debug("received packet's protocol: %x\n", ntohs(skb->protocol));
 467         skb_debug(skb);
 468         /* sigh, interface is down? */
 469         if (unlikely(!(net_dev->flags & IFF_UP)))
 470                 goto dropped;
 471         net_dev->stats.rx_packets++;
 472         net_dev->stats.rx_bytes += skb->len;
 473         memset(ATM_SKB(skb), 0, sizeof(struct atm_skb_data));
 474         netif_rx(skb);
 475         return;
 476
 477 dropped:
 478         net_dev->stats.rx_dropped++;
 479         goto free_skb;
 480 error:
 481         net_dev->stats.rx_errors++;
 482 free_skb:
 483         dev_kfree_skb(skb);
 484 }
 485
 486 /*
 487  * Assign a vcc to a dev
 488  * Note: we do not have explicit unassign, but look at _push()
 489  */
 490 static int br2684_regvcc(struct atm_vcc *atmvcc, void __user * arg)
 491 {
 492         struct sk_buff_head queue;
 493         int err;
 494         struct br2684_vcc *brvcc;
 495         struct sk_buff *skb, *tmp;
 496         struct sk_buff_head *rq;
 497         struct br2684_dev *brdev;
 498         struct net_device *net_dev;
 499         struct atm_backend_br2684 be;
 500         unsigned long flags;
 501
 502         if (copy_from_user(&be, arg, sizeof be))
 503                 return -EFAULT;
 504         brvcc = kzalloc(sizeof(struct br2684_vcc), GFP_KERNEL);
 505         if (!brvcc)
 506                 return -ENOMEM;
 507         write_lock_irq(&devs_lock);
 508         net_dev = br2684_find_dev(&be.ifspec);
 509         if (net_dev == NULL) {
 510                 pr_err("tried to attach to non-existent device\n");
 511                 err = -ENXIO;
 512                 goto error;
 513         }
 514         brdev = BRPRIV(net_dev);
 515         if (atmvcc->push == NULL) {
 516                 err = -EBADFD;
 517                 goto error;
 518         }
 519         if (!list_empty(&brdev->brvccs)) {
 520                 /* Only 1 VCC/dev right now */
 521                 err = -EEXIST;
 522                 goto error;
 523         }
 524         if (be.fcs_in != BR2684_FCSIN_NO ||
 525             be.fcs_out != BR2684_FCSOUT_NO ||
 526             be.fcs_auto || be.has_vpiid || be.send_padding ||
 527             (be.encaps != BR2684_ENCAPS_VC &&
 528              be.encaps != BR2684_ENCAPS_LLC) ||
 529             be.min_size != 0) {
 530                 err = -EINVAL;
 531                 goto error;
 532         }
 533         pr_debug("vcc=%p, encaps=%d, brvcc=%p\n", atmvcc, be.encaps, brvcc);
 534         if (list_empty(&brdev->brvccs) && !brdev->mac_was_set) {
 535                 unsigned char *esi = atmvcc->dev->esi;
 536                 if (esi[0] | esi[1] | esi[2] | esi[3] | esi[4] | esi[5])
 537                         memcpy(net_dev->dev_addr, esi, net_dev->addr_len);
 538                 else
 539                         net_dev->dev_addr[2] = 1;
 540         }
 541         list_add(&brvcc->brvccs, &brdev->brvccs);
 542         write_unlock_irq(&devs_lock);
 543         brvcc->device = net_dev;
 544         brvcc->atmvcc = atmvcc;
 545         atmvcc->user_back = brvcc;
 546         brvcc->encaps = (enum br2684_encaps)be.encaps;
 547         brvcc->old_push = atmvcc->push;
 548         brvcc->old_pop = atmvcc->pop;
 549         barrier();
 550         atmvcc->push = br2684_push;
 551         atmvcc->pop = br2684_pop;
 552
 553         __skb_queue_head_init(&queue);
 554         rq = &sk_atm(atmvcc)->sk_receive_queue;
 555
 556         spin_lock_irqsave(&rq->lock, flags);
 557         skb_queue_splice_init(rq, &queue);
 558         spin_unlock_irqrestore(&rq->lock, flags);
 559
 560         skb_queue_walk_safe(&queue, skb, tmp) {
 561                 struct net_device *dev;
 562
 563                 br2684_push(atmvcc, skb);
 564                 dev = skb->dev;
 565
 566                 dev->stats.rx_bytes -= skb->len;
 567                 dev->stats.rx_packets--;
 568         }
 569
 570         /* initialize netdev carrier state */
 571         if (atmvcc->dev->signal == ATM_PHY_SIG_LOST)
 572                 netif_carrier_off(net_dev);
 573         else
 574                 netif_carrier_on(net_dev);
 575
 576         __module_get(THIS_MODULE);
 577         return 0;
 578
 579 error:
 580         write_unlock_irq(&devs_lock);
 581         kfree(brvcc);
 582         return err;
 583 }
 584
 585 static const struct net_device_ops br2684_netdev_ops = {
 586         .ndo_start_xmit         = br2684_start_xmit,
 587         .ndo_set_mac_address    = br2684_mac_addr,
 588         .ndo_change_mtu         = eth_change_mtu,
 589         .ndo_validate_addr      = eth_validate_addr,
 590 };
 591
 592 static const struct net_device_ops br2684_netdev_ops_routed = {
 593         .ndo_start_xmit         = br2684_start_xmit,
 594         .ndo_set_mac_address    = br2684_mac_addr,
 595         .ndo_change_mtu         = eth_change_mtu
 596 };
 597
 598 static void br2684_setup(struct net_device *netdev)
 599 {
 600         struct br2684_dev *brdev = BRPRIV(netdev);
 601
 602         ether_setup(netdev);
 603         brdev->net_dev = netdev;
 604
 605         netdev->netdev_ops = &br2684_netdev_ops;
 606
 607         INIT_LIST_HEAD(&brdev->brvccs);
 608 }
 609
 610 static void br2684_setup_routed(struct net_device *netdev)
 611 {
 612         struct br2684_dev *brdev = BRPRIV(netdev);
 613
 614         brdev->net_dev = netdev;
 615         netdev->hard_header_len = 0;
 616         netdev->netdev_ops = &br2684_netdev_ops_routed;
 617         netdev->addr_len = 0;
 618         netdev->mtu = 1500;
 619         netdev->type = ARPHRD_PPP;
 620         netdev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
 621         netdev->tx_queue_len = 100;
 622         INIT_LIST_HEAD(&brdev->brvccs);
 623 }
 624
 625 static int br2684_create(void __user *arg)
 626 {
 627         int err;
 628         struct net_device *netdev;
 629         struct br2684_dev *brdev;
 630         struct atm_newif_br2684 ni;
 631         enum br2684_payload payload;
 632
 633         pr_debug("\n");
 634
 635         if (copy_from_user(&ni, arg, sizeof ni))
 636                 return -EFAULT;
 637
 638         if (ni.media & BR2684_FLAG_ROUTED)
 639                 payload = p_routed;
 640         else
 641                 payload = p_bridged;
 642         ni.media &= 0xffff;     /* strip flags */
 643
 644         if (ni.media != BR2684_MEDIA_ETHERNET || ni.mtu != 1500)
 645                 return -EINVAL;
 646
 647         netdev = alloc_netdev(sizeof(struct br2684_dev),
 648                               ni.ifname[0] ? ni.ifname : "nas%d",
 649                               (payload == p_routed) ?
 650                               br2684_setup_routed : br2684_setup);
 651         if (!netdev)
 652                 return -ENOMEM;
 653
 654         brdev = BRPRIV(netdev);
 655
 656         pr_debug("registered netdev %s\n", netdev->name);
 657         /* open, stop, do_ioctl ? */
 658         err = register_netdev(netdev);
 659         if (err < 0) {
 660                 pr_err("register_netdev failed\n");
 661                 free_netdev(netdev);
 662                 return err;
 663         }
 664
 665         write_lock_irq(&devs_lock);
 666
 667         brdev->payload = payload;
 668
 669         if (list_empty(&br2684_devs)) {
 670                 /* 1st br2684 device */
 671                 brdev->number = 1;
 672         } else
 673                 brdev->number = BRPRIV(list_entry_brdev(br2684_devs.prev))->number + 1;
 674
 675         list_add_tail(&brdev->br2684_devs, &br2684_devs);
 676         write_unlock_irq(&devs_lock);
 677         return 0;
 678 }
 679
 680 /*
 681  * This handles ioctls actually performed on our vcc - we must return
 682  * -ENOIOCTLCMD for any unrecognized ioctl
 683  */
 684 static int br2684_ioctl(struct socket *sock, unsigned int cmd,
 685                         unsigned long arg)
 686 {
 687         struct atm_vcc *atmvcc = ATM_SD(sock);
 688         void __user *argp = (void __user *)arg;
 689         atm_backend_t b;
 690
 691         int err;
 692         switch (cmd) {
 693         case ATM_SETBACKEND:
 694         case ATM_NEWBACKENDIF:
 695                 err = get_user(b, (atm_backend_t __user *) argp);
 696                 if (err)
 697                         return -EFAULT;
 698                 if (b != ATM_BACKEND_BR2684)
 699                         return -ENOIOCTLCMD;
 700                 if (!capable(CAP_NET_ADMIN))
 701                         return -EPERM;
 702                 if (cmd == ATM_SETBACKEND)
 703                         return br2684_regvcc(atmvcc, argp);
 704                 else
 705                         return br2684_create(argp);
 706 #ifdef CONFIG_ATM_BR2684_IPFILTER
 707         case BR2684_SETFILT:
 708                 if (atmvcc->push != br2684_push)
 709                         return -ENOIOCTLCMD;
 710                 if (!capable(CAP_NET_ADMIN))
 711                         return -EPERM;
 712                 err = br2684_setfilt(atmvcc, argp);
 713
 714                 return err;
 715 #endif /* CONFIG_ATM_BR2684_IPFILTER */
 716         }
 717         return -ENOIOCTLCMD;
 718 }
 719
 720 static struct atm_ioctl br2684_ioctl_ops = {
 721         .owner = THIS_MODULE,
 722         .ioctl = br2684_ioctl,
 723 };
 724
 725 #ifdef CONFIG_PROC_FS
 726 static void *br2684_seq_start(struct seq_file *seq, loff_t * pos)
 727         __acquires(devs_lock)
 728 {
 729         read_lock(&devs_lock);
 730         return seq_list_start(&br2684_devs, *pos);
 731 }
 732
 733 static void *br2684_seq_next(struct seq_file *seq, void *v, loff_t * pos)
 734 {
 735         return seq_list_next(v, &br2684_devs, pos);
 736 }
 737
 738 static void br2684_seq_stop(struct seq_file *seq, void *v)
 739         __releases(devs_lock)
 740 {
 741         read_unlock(&devs_lock);
 742 }
 743
 744 static int br2684_seq_show(struct seq_file *seq, void *v)
 745 {
 746         const struct br2684_dev *brdev = list_entry(v, struct br2684_dev,
 747                                                     br2684_devs);
 748         const struct net_device *net_dev = brdev->net_dev;
 749         const struct br2684_vcc *brvcc;
 750
 751         seq_printf(seq, "dev %.16s: num=%d, mac=%pM (%s)\n",
 752                    net_dev->name,
 753                    brdev->number,
 754                    net_dev->dev_addr,
 755                    brdev->mac_was_set ? "set" : "auto");
 756
 757         list_for_each_entry(brvcc, &brdev->brvccs, brvccs) {
 758                 seq_printf(seq, "  vcc %d.%d.%d: encaps=%s payload=%s"
 759                            ", failed copies %u/%u"
 760                            "\n", brvcc->atmvcc->dev->number,
 761                            brvcc->atmvcc->vpi, brvcc->atmvcc->vci,
 762                            (brvcc->encaps == e_llc) ? "LLC" : "VC",
 763                            (brdev->payload == p_bridged) ? "bridged" : "routed",
 764                            brvcc->copies_failed, brvcc->copies_needed);
 765 #ifdef CONFIG_ATM_BR2684_IPFILTER
 766 #define b1(var, byte)   ((u8 *) &brvcc->filter.var)[byte]
 767 #define bs(var)         b1(var, 0), b1(var, 1), b1(var, 2), b1(var, 3)
 768                 if (brvcc->filter.netmask != 0)
 769                         seq_printf(seq, "    filter=%d.%d.%d.%d/"
 770                                    "%d.%d.%d.%d\n", bs(prefix), bs(netmask));
 771 #undef bs
 772 #undef b1
 773 #endif /* CONFIG_ATM_BR2684_IPFILTER */
 774         }
 775         return 0;
 776 }
 777
 778 static const struct seq_operations br2684_seq_ops = {
 779         .start = br2684_seq_start,
 780         .next = br2684_seq_next,
 781         .stop = br2684_seq_stop,
 782         .show = br2684_seq_show,
 783 };
 784
 785 static int br2684_proc_open(struct inode *inode, struct file *file)
 786 {
 787         return seq_open(file, &br2684_seq_ops);
 788 }
 789
 790 static const struct file_operations br2684_proc_ops = {
 791         .owner = THIS_MODULE,
 792         .open = br2684_proc_open,
 793         .read = seq_read,
 794         .llseek = seq_lseek,
 795         .release = seq_release,
 796 };
 797
 798 extern struct proc_dir_entry *atm_proc_root;    /* from proc.c */
 799 #endif /* CONFIG_PROC_FS */
 800
 801 static int __init br2684_init(void)
 802 {
 803 #ifdef CONFIG_PROC_FS
 804         struct proc_dir_entry *p;
 805         p = proc_create("br2684", 0, atm_proc_root, &br2684_proc_ops);
 806         if (p == NULL)
 807                 return -ENOMEM;
 808 #endif
 809         register_atm_ioctl(&br2684_ioctl_ops);
 810         register_atmdevice_notifier(&atm_dev_notifier);
 811         return 0;
 812 }
 813
 814 static void __exit br2684_exit(void)
 815 {
 816         struct net_device *net_dev;
 817         struct br2684_dev *brdev;
 818         struct br2684_vcc *brvcc;
 819         deregister_atm_ioctl(&br2684_ioctl_ops);
 820
 821 #ifdef CONFIG_PROC_FS
 822         remove_proc_entry("br2684", atm_proc_root);
 823 #endif
 824
 825
 826         unregister_atmdevice_notifier(&atm_dev_notifier);
 827
 828         while (!list_empty(&br2684_devs)) {
 829                 net_dev = list_entry_brdev(br2684_devs.next);
 830                 brdev = BRPRIV(net_dev);
 831                 while (!list_empty(&brdev->brvccs)) {
 832                         brvcc = list_entry_brvcc(brdev->brvccs.next);
 833                         br2684_close_vcc(brvcc);
 834                 }
 835
 836                 list_del(&brdev->br2684_devs);
 837                 unregister_netdev(net_dev);
 838                 free_netdev(net_dev);
 839         }
 840 }
 841
 842 module_init(br2684_init);
 843 module_exit(br2684_exit);
 844
 845 MODULE_AUTHOR("Marcell GAL");
 846 MODULE_DESCRIPTION("RFC2684 bridged protocols over ATM/AAL5");
 847 MODULE_LICENSE("GPL");