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 #include <linux/module.h>
  10 #include <linux/init.h>
  11 #include <linux/kernel.h>
  12 #include <linux/list.h>
  13 #include <linux/netdevice.h>
  14 #include <linux/skbuff.h>
  15 #include <linux/etherdevice.h>
  16 #include <linux/rtnetlink.h>
  17 #include <linux/ip.h>
  18 #include <asm/uaccess.h>
  19 #include <net/arp.h>
  20 #include <linux/atm.h>
  21 #include <linux/atmdev.h>
  22 #include <linux/capability.h>
  23 #include <linux/seq_file.h>
  24
  25 #include <linux/atmbr2684.h>
  26
  27 #include "common.h"
  28
  29 #ifdef SKB_DEBUG
  30 static void skb_debug(const struct sk_buff *skb)
  31 {
  32 #define NUM2PRINT 50
  33         char buf[NUM2PRINT * 3 + 1];    /* 3 chars per byte */
  34         int i = 0;
  35         for (i = 0; i < skb->len && i < NUM2PRINT; i++) {
  36                 sprintf(buf + i * 3, "%2.2x ", 0xff & skb->data[i]);
  37         }
  38         printk(KERN_DEBUG "br2684: skb: %s\n", buf);
  39 }
  40 #else
  41 #define skb_debug(skb)  do {} while (0)
  42 #endif
  43
  44 #define BR2684_ETHERTYPE_LEN    2
  45 #define BR2684_PAD_LEN          2
  46
  47 #define LLC             0xaa, 0xaa, 0x03
  48 #define SNAP_BRIDGED    0x00, 0x80, 0xc2
  49 #define SNAP_ROUTED     0x00, 0x00, 0x00
  50 #define PID_ETHERNET    0x00, 0x07
  51 #define ETHERTYPE_IPV4  0x08, 0x00
  52 #define ETHERTYPE_IPV6  0x86, 0xdd
  53 #define PAD_BRIDGED     0x00, 0x00
  54
  55 static const unsigned char ethertype_ipv4[] = { ETHERTYPE_IPV4 };
  56 static const unsigned char ethertype_ipv6[] = { ETHERTYPE_IPV6 };
  57 static const unsigned char llc_oui_pid_pad[] =
  58                         { LLC, SNAP_BRIDGED, PID_ETHERNET, PAD_BRIDGED };
  59 static const unsigned char llc_oui_ipv4[] = { LLC, SNAP_ROUTED, ETHERTYPE_IPV4 };
  60 static const unsigned char llc_oui_ipv6[] = { LLC, SNAP_ROUTED, ETHERTYPE_IPV6 };
  61
  62 enum br2684_encaps {
  63         e_vc = BR2684_ENCAPS_VC,
  64         e_llc = BR2684_ENCAPS_LLC,
  65 };
  66
  67 struct br2684_vcc {
  68         struct atm_vcc *atmvcc;
  69         struct net_device *device;
  70         /* keep old push, pop functions for chaining */
  71         void (*old_push) (struct atm_vcc * vcc, struct sk_buff * skb);
  72         void (*old_pop)(struct atm_vcc *vcc, struct sk_buff *skb);
  73         enum br2684_encaps encaps;
  74         struct list_head brvccs;
  75 #ifdef CONFIG_ATM_BR2684_IPFILTER
  76         struct br2684_filter filter;
  77 #endif /* CONFIG_ATM_BR2684_IPFILTER */
  78         unsigned copies_needed, copies_failed;
  79 };
  80
  81 struct br2684_dev {
  82         struct net_device *net_dev;
  83         struct list_head br2684_devs;
  84         int number;
  85         struct list_head brvccs;        /* one device <=> one vcc (before xmas) */
  86         int mac_was_set;
  87         enum br2684_payload payload;
  88 };
  89
  90 /*
  91  * This lock should be held for writing any time the list of devices or
  92  * their attached vcc's could be altered.  It should be held for reading
  93  * any time these are being queried.  Note that we sometimes need to
  94  * do read-locking under interrupt context, so write locking must block
  95  * the current CPU's interrupts
  96  */
  97 static DEFINE_RWLOCK(devs_lock);
  98
  99 static LIST_HEAD(br2684_devs);
 100
 101 static inline struct br2684_dev *BRPRIV(const struct net_device *net_dev)
 102 {
 103         return (struct br2684_dev *)netdev_priv(net_dev);
 104 }
 105
 106 static inline struct net_device *list_entry_brdev(const struct list_head *le)
 107 {
 108         return list_entry(le, struct br2684_dev, br2684_devs)->net_dev;
 109 }
 110
 111 static inline struct br2684_vcc *BR2684_VCC(const struct atm_vcc *atmvcc)
 112 {
 113         return (struct br2684_vcc *)(atmvcc->user_back);
 114 }
 115
 116 static inline struct br2684_vcc *list_entry_brvcc(const struct list_head *le)
 117 {
 118         return list_entry(le, struct br2684_vcc, brvccs);
 119 }
 120
 121 /* Caller should hold read_lock(&devs_lock) */
 122 static struct net_device *br2684_find_dev(const struct br2684_if_spec *s)
 123 {
 124         struct list_head *lh;
 125         struct net_device *net_dev;
 126         switch (s->method) {
 127         case BR2684_FIND_BYNUM:
 128                 list_for_each(lh, &br2684_devs) {
 129                         net_dev = list_entry_brdev(lh);
 130                         if (BRPRIV(net_dev)->number == s->spec.devnum)
 131                                 return net_dev;
 132                 }
 133                 break;
 134         case BR2684_FIND_BYIFNAME:
 135                 list_for_each(lh, &br2684_devs) {
 136                         net_dev = list_entry_brdev(lh);
 137                         if (!strncmp(net_dev->name, s->spec.ifname, IFNAMSIZ))
 138                                 return net_dev;
 139                 }
 140                 break;
 141         }
 142         return NULL;
 143 }
 144
 145 /* chained vcc->pop function.  Check if we should wake the netif_queue */
 146 static void br2684_pop(struct atm_vcc *vcc, struct sk_buff *skb)
 147 {
 148         struct br2684_vcc *brvcc = BR2684_VCC(vcc);
 149         struct net_device *net_dev = skb->dev;
 150
 151         pr_debug("br2684_pop(vcc %p ; net_dev %p )\n", vcc, net_dev);
 152         brvcc->old_pop(vcc, skb);
 153
 154         if (!net_dev)
 155                 return;
 156
 157         if (atm_may_send(vcc, 0))
 158                 netif_wake_queue(net_dev);
 159
 160 }
 161 /*
 162  * Send a packet out a particular vcc.  Not to useful right now, but paves
 163  * the way for multiple vcc's per itf.  Returns true if we can send,
 164  * otherwise false
 165  */
 166 static int br2684_xmit_vcc(struct sk_buff *skb, struct net_device *dev,
 167                            struct br2684_vcc *brvcc)
 168 {
 169         struct br2684_dev *brdev = BRPRIV(dev);
 170         struct atm_vcc *atmvcc;
 171         int minheadroom = (brvcc->encaps == e_llc) ? 10 : 2;
 172
 173         if (skb_headroom(skb) < minheadroom) {
 174                 struct sk_buff *skb2 = skb_realloc_headroom(skb, minheadroom);
 175                 brvcc->copies_needed++;
 176                 dev_kfree_skb(skb);
 177                 if (skb2 == NULL) {
 178                         brvcc->copies_failed++;
 179                         return 0;
 180                 }
 181                 skb = skb2;
 182         }
 183
 184         if (brvcc->encaps == e_llc) {
 185                 if (brdev->payload == p_bridged) {
 186                         skb_push(skb, sizeof(llc_oui_pid_pad));
 187                         skb_copy_to_linear_data(skb, llc_oui_pid_pad,
 188                                                 sizeof(llc_oui_pid_pad));
 189                 } else if (brdev->payload == p_routed) {
 190                         unsigned short prot = ntohs(skb->protocol);
 191
 192                         skb_push(skb, sizeof(llc_oui_ipv4));
 193                         switch (prot) {
 194                         case ETH_P_IP:
 195                                 skb_copy_to_linear_data(skb, llc_oui_ipv4,
 196                                                         sizeof(llc_oui_ipv4));
 197                                 break;
 198                         case ETH_P_IPV6:
 199                                 skb_copy_to_linear_data(skb, llc_oui_ipv6,
 200                                                         sizeof(llc_oui_ipv6));
 201                                 break;
 202                         default:
 203                                 dev_kfree_skb(skb);
 204                                 return 0;
 205                         }
 206                 }
 207         } else { /* e_vc */
 208                 if (brdev->payload == p_bridged) {
 209                         skb_push(skb, 2);
 210                         memset(skb->data, 0, 2);
 211                 } else { /* p_routed */
 212                         skb_pull(skb, ETH_HLEN);
 213                 }
 214         }
 215         skb_debug(skb);
 216
 217         ATM_SKB(skb)->vcc = atmvcc = brvcc->atmvcc;
 218         pr_debug("atm_skb(%p)->vcc(%p)->dev(%p)\n", skb, atmvcc, atmvcc->dev);
 219         atomic_add(skb->truesize, &sk_atm(atmvcc)->sk_wmem_alloc);
 220         ATM_SKB(skb)->atm_options = atmvcc->atm_options;
 221         dev->stats.tx_packets++;
 222         dev->stats.tx_bytes += skb->len;
 223         atmvcc->send(atmvcc, skb);
 224
 225         if (!atm_may_send(atmvcc, 0)) {
 226                 netif_stop_queue(brvcc->device);
 227                 /*check for race with br2684_pop*/
 228                 if (atm_may_send(atmvcc, 0))
 229                         netif_start_queue(brvcc->device);
 230         }
 231
 232         return 1;
 233 }
 234
 235 static inline struct br2684_vcc *pick_outgoing_vcc(const struct sk_buff *skb,
 236                                                    const struct br2684_dev *brdev)
 237 {
 238         return list_empty(&brdev->brvccs) ? NULL : list_entry_brvcc(brdev->brvccs.next);        /* 1 vcc/dev right now */
 239 }
 240
 241 static netdev_tx_t br2684_start_xmit(struct sk_buff *skb,
 242                                      struct net_device *dev)
 243 {
 244         struct br2684_dev *brdev = BRPRIV(dev);
 245         struct br2684_vcc *brvcc;
 246
 247         pr_debug("br2684_start_xmit, skb_dst(skb)=%p\n", skb_dst(skb));
 248         read_lock(&devs_lock);
 249         brvcc = pick_outgoing_vcc(skb, brdev);
 250         if (brvcc == NULL) {
 251                 pr_debug("no vcc attached to dev %s\n", dev->name);
 252                 dev->stats.tx_errors++;
 253                 dev->stats.tx_carrier_errors++;
 254                 /* netif_stop_queue(dev); */
 255                 dev_kfree_skb(skb);
 256                 read_unlock(&devs_lock);
 257                 return NETDEV_TX_OK;
 258         }
 259         if (!br2684_xmit_vcc(skb, dev, brvcc)) {
 260                 /*
 261                  * We should probably use netif_*_queue() here, but that
 262                  * involves added complication.  We need to walk before
 263                  * we can run.
 264                  *
 265                  * Don't free here! this pointer might be no longer valid!
 266                  */
 267                 dev->stats.tx_errors++;
 268                 dev->stats.tx_fifo_errors++;
 269         }
 270         read_unlock(&devs_lock);
 271         return NETDEV_TX_OK;
 272 }
 273
 274 /*
 275  * We remember when the MAC gets set, so we don't override it later with
 276  * the ESI of the ATM card of the first VC
 277  */
 278 static int br2684_mac_addr(struct net_device *dev, void *p)
 279 {
 280         int err = eth_mac_addr(dev, p);
 281         if (!err)
 282                 BRPRIV(dev)->mac_was_set = 1;
 283         return err;
 284 }
 285
 286 #ifdef CONFIG_ATM_BR2684_IPFILTER
 287 /* this IOCTL is experimental. */
 288 static int br2684_setfilt(struct atm_vcc *atmvcc, void __user * arg)
 289 {
 290         struct br2684_vcc *brvcc;
 291         struct br2684_filter_set fs;
 292
 293         if (copy_from_user(&fs, arg, sizeof fs))
 294                 return -EFAULT;
 295         if (fs.ifspec.method != BR2684_FIND_BYNOTHING) {
 296                 /*
 297                  * This is really a per-vcc thing, but we can also search
 298                  * by device.
 299                  */
 300                 struct br2684_dev *brdev;
 301                 read_lock(&devs_lock);
 302                 brdev = BRPRIV(br2684_find_dev(&fs.ifspec));
 303                 if (brdev == NULL || list_empty(&brdev->brvccs) || brdev->brvccs.next != brdev->brvccs.prev)    /* >1 VCC */
 304                         brvcc = NULL;
 305                 else
 306                         brvcc = list_entry_brvcc(brdev->brvccs.next);
 307                 read_unlock(&devs_lock);
 308                 if (brvcc == NULL)
 309                         return -ESRCH;
 310         } else
 311                 brvcc = BR2684_VCC(atmvcc);
 312         memcpy(&brvcc->filter, &fs.filter, sizeof(brvcc->filter));
 313         return 0;
 314 }
 315
 316 /* Returns 1 if packet should be dropped */
 317 static inline int
 318 packet_fails_filter(__be16 type, struct br2684_vcc *brvcc, struct sk_buff *skb)
 319 {
 320         if (brvcc->filter.netmask == 0)
 321                 return 0;       /* no filter in place */
 322         if (type == htons(ETH_P_IP) &&
 323             (((struct iphdr *)(skb->data))->daddr & brvcc->filter.
 324              netmask) == brvcc->filter.prefix)
 325                 return 0;
 326         if (type == htons(ETH_P_ARP))
 327                 return 0;
 328         /*
 329          * TODO: we should probably filter ARPs too.. don't want to have
 330          * them returning values that don't make sense, or is that ok?
 331          */
 332         return 1;               /* drop */
 333 }
 334 #endif /* CONFIG_ATM_BR2684_IPFILTER */
 335
 336 static void br2684_close_vcc(struct br2684_vcc *brvcc)
 337 {
 338         pr_debug("removing VCC %p from dev %p\n", brvcc, brvcc->device);
 339         write_lock_irq(&devs_lock);
 340         list_del(&brvcc->brvccs);
 341         write_unlock_irq(&devs_lock);
 342         brvcc->atmvcc->user_back = NULL;        /* what about vcc->recvq ??? */
 343         brvcc->old_push(brvcc->atmvcc, NULL);   /* pass on the bad news */
 344         kfree(brvcc);
 345         module_put(THIS_MODULE);
 346 }
 347
 348 /* when AAL5 PDU comes in: */
 349 static void br2684_push(struct atm_vcc *atmvcc, struct sk_buff *skb)
 350 {
 351         struct br2684_vcc *brvcc = BR2684_VCC(atmvcc);
 352         struct net_device *net_dev = brvcc->device;
 353         struct br2684_dev *brdev = BRPRIV(net_dev);
 354
 355         pr_debug("br2684_push\n");
 356
 357         if (unlikely(skb == NULL)) {
 358                 /* skb==NULL means VCC is being destroyed */
 359                 br2684_close_vcc(brvcc);
 360                 if (list_empty(&brdev->brvccs)) {
 361                         write_lock_irq(&devs_lock);
 362                         list_del(&brdev->br2684_devs);
 363                         write_unlock_irq(&devs_lock);
 364                         unregister_netdev(net_dev);
 365                         free_netdev(net_dev);
 366                 }
 367                 return;
 368         }
 369
 370         skb_debug(skb);
 371         atm_return(atmvcc, skb->truesize);
 372         pr_debug("skb from brdev %p\n", brdev);
 373         if (brvcc->encaps == e_llc) {
 374
 375                 if (skb->len > 7 && skb->data[7] == 0x01)
 376                         __skb_trim(skb, skb->len - 4);
 377
 378                 /* accept packets that have "ipv[46]" in the snap header */
 379                 if ((skb->len >= (sizeof(llc_oui_ipv4)))
 380                     &&
 381                     (memcmp
 382                      (skb->data, llc_oui_ipv4,
 383                       sizeof(llc_oui_ipv4) - BR2684_ETHERTYPE_LEN) == 0)) {
 384                         if (memcmp
 385                             (skb->data + 6, ethertype_ipv6,
 386                              sizeof(ethertype_ipv6)) == 0)
 387                                 skb->protocol = htons(ETH_P_IPV6);
 388                         else if (memcmp
 389                                  (skb->data + 6, ethertype_ipv4,
 390                                   sizeof(ethertype_ipv4)) == 0)
 391                                 skb->protocol = htons(ETH_P_IP);
 392                         else
 393                                 goto error;
 394                         skb_pull(skb, sizeof(llc_oui_ipv4));
 395                         skb_reset_network_header(skb);
 396                         skb->pkt_type = PACKET_HOST;
 397                         /*
 398                          * Let us waste some time for checking the encapsulation.
 399                          * Note, that only 7 char is checked so frames with a valid FCS
 400                          * are also accepted (but FCS is not checked of course).
 401                          */
 402                 } else if ((skb->len >= sizeof(llc_oui_pid_pad)) &&
 403                            (memcmp(skb->data, llc_oui_pid_pad, 7) == 0)) {
 404                         skb_pull(skb, sizeof(llc_oui_pid_pad));
 405                         skb->protocol = eth_type_trans(skb, net_dev);
 406                 } else
 407                         goto error;
 408
 409         } else { /* e_vc */
 410                 if (brdev->payload == p_routed) {
 411                         struct iphdr *iph;
 412
 413                         skb_reset_network_header(skb);
 414                         iph = ip_hdr(skb);
 415                         if (iph->version == 4)
 416                                 skb->protocol = htons(ETH_P_IP);
 417                         else if (iph->version == 6)
 418                                 skb->protocol = htons(ETH_P_IPV6);
 419                         else
 420                                 goto error;
 421                         skb->pkt_type = PACKET_HOST;
 422                 } else { /* p_bridged */
 423                         /* first 2 chars should be 0 */
 424                         if (*((u16 *) (skb->data)) != 0)
 425                                 goto error;
 426                         skb_pull(skb, BR2684_PAD_LEN);
 427                         skb->protocol = eth_type_trans(skb, net_dev);
 428                 }
 429         }
 430
 431 #ifdef CONFIG_ATM_BR2684_IPFILTER
 432         if (unlikely(packet_fails_filter(skb->protocol, brvcc, skb)))
 433                 goto dropped;
 434 #endif /* CONFIG_ATM_BR2684_IPFILTER */
 435         skb->dev = net_dev;
 436         ATM_SKB(skb)->vcc = atmvcc;     /* needed ? */
 437         pr_debug("received packet's protocol: %x\n", ntohs(skb->protocol));
 438         skb_debug(skb);
 439         /* sigh, interface is down? */
 440         if (unlikely(!(net_dev->flags & IFF_UP)))
 441                 goto dropped;
 442         net_dev->stats.rx_packets++;
 443         net_dev->stats.rx_bytes += skb->len;
 444         memset(ATM_SKB(skb), 0, sizeof(struct atm_skb_data));
 445         netif_rx(skb);
 446         return;
 447
 448 dropped:
 449         net_dev->stats.rx_dropped++;
 450         goto free_skb;
 451 error:
 452         net_dev->stats.rx_errors++;
 453 free_skb:
 454         dev_kfree_skb(skb);
 455         return;
 456 }
 457
 458 /*
 459  * Assign a vcc to a dev
 460  * Note: we do not have explicit unassign, but look at _push()
 461  */
 462 static int br2684_regvcc(struct atm_vcc *atmvcc, void __user * arg)
 463 {
 464         struct sk_buff_head queue;
 465         int err;
 466         struct br2684_vcc *brvcc;
 467         struct sk_buff *skb, *tmp;
 468         struct sk_buff_head *rq;
 469         struct br2684_dev *brdev;
 470         struct net_device *net_dev;
 471         struct atm_backend_br2684 be;
 472         unsigned long flags;
 473
 474         if (copy_from_user(&be, arg, sizeof be))
 475                 return -EFAULT;
 476         brvcc = kzalloc(sizeof(struct br2684_vcc), GFP_KERNEL);
 477         if (!brvcc)
 478                 return -ENOMEM;
 479         write_lock_irq(&devs_lock);
 480         net_dev = br2684_find_dev(&be.ifspec);
 481         if (net_dev == NULL) {
 482                 printk(KERN_ERR
 483                        "br2684: tried to attach to non-existant device\n");
 484                 err = -ENXIO;
 485                 goto error;
 486         }
 487         brdev = BRPRIV(net_dev);
 488         if (atmvcc->push == NULL) {
 489                 err = -EBADFD;
 490                 goto error;
 491         }
 492         if (!list_empty(&brdev->brvccs)) {
 493                 /* Only 1 VCC/dev right now */
 494                 err = -EEXIST;
 495                 goto error;
 496         }
 497         if (be.fcs_in != BR2684_FCSIN_NO || be.fcs_out != BR2684_FCSOUT_NO ||
 498             be.fcs_auto || be.has_vpiid || be.send_padding || (be.encaps !=
 499                                                                BR2684_ENCAPS_VC
 500                                                                && be.encaps !=
 501                                                                BR2684_ENCAPS_LLC)
 502             || be.min_size != 0) {
 503                 err = -EINVAL;
 504                 goto error;
 505         }
 506         pr_debug("br2684_regvcc vcc=%p, encaps=%d, brvcc=%p\n", atmvcc,
 507                  be.encaps, brvcc);
 508         if (list_empty(&brdev->brvccs) && !brdev->mac_was_set) {
 509                 unsigned char *esi = atmvcc->dev->esi;
 510                 if (esi[0] | esi[1] | esi[2] | esi[3] | esi[4] | esi[5])
 511                         memcpy(net_dev->dev_addr, esi, net_dev->addr_len);
 512                 else
 513                         net_dev->dev_addr[2] = 1;
 514         }
 515         list_add(&brvcc->brvccs, &brdev->brvccs);
 516         write_unlock_irq(&devs_lock);
 517         brvcc->device = net_dev;
 518         brvcc->atmvcc = atmvcc;
 519         atmvcc->user_back = brvcc;
 520         brvcc->encaps = (enum br2684_encaps)be.encaps;
 521         brvcc->old_push = atmvcc->push;
 522         brvcc->old_pop = atmvcc->pop;
 523         barrier();
 524         atmvcc->push = br2684_push;
 525         atmvcc->pop = br2684_pop;
 526
 527         __skb_queue_head_init(&queue);
 528         rq = &sk_atm(atmvcc)->sk_receive_queue;
 529
 530         spin_lock_irqsave(&rq->lock, flags);
 531         skb_queue_splice_init(rq, &queue);
 532         spin_unlock_irqrestore(&rq->lock, flags);
 533
 534         skb_queue_walk_safe(&queue, skb, tmp) {
 535                 struct net_device *dev = skb->dev;
 536
 537                 dev->stats.rx_bytes -= skb->len;
 538                 dev->stats.rx_packets--;
 539
 540                 br2684_push(atmvcc, skb);
 541         }
 542         __module_get(THIS_MODULE);
 543         return 0;
 544       error:
 545         write_unlock_irq(&devs_lock);
 546         kfree(brvcc);
 547         return err;
 548 }
 549
 550 static const struct net_device_ops br2684_netdev_ops = {
 551         .ndo_start_xmit         = br2684_start_xmit,
 552         .ndo_set_mac_address    = br2684_mac_addr,
 553         .ndo_change_mtu         = eth_change_mtu,
 554         .ndo_validate_addr      = eth_validate_addr,
 555 };
 556
 557 static const struct net_device_ops br2684_netdev_ops_routed = {
 558         .ndo_start_xmit         = br2684_start_xmit,
 559         .ndo_set_mac_address    = br2684_mac_addr,
 560         .ndo_change_mtu         = eth_change_mtu
 561 };
 562
 563 static void br2684_setup(struct net_device *netdev)
 564 {
 565         struct br2684_dev *brdev = BRPRIV(netdev);
 566
 567         ether_setup(netdev);
 568         brdev->net_dev = netdev;
 569
 570         netdev->netdev_ops = &br2684_netdev_ops;
 571
 572         INIT_LIST_HEAD(&brdev->brvccs);
 573 }
 574
 575 static void br2684_setup_routed(struct net_device *netdev)
 576 {
 577         struct br2684_dev *brdev = BRPRIV(netdev);
 578
 579         brdev->net_dev = netdev;
 580         netdev->hard_header_len = 0;
 581         netdev->netdev_ops = &br2684_netdev_ops_routed;
 582         netdev->addr_len = 0;
 583         netdev->mtu = 1500;
 584         netdev->type = ARPHRD_PPP;
 585         netdev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
 586         netdev->tx_queue_len = 100;
 587         INIT_LIST_HEAD(&brdev->brvccs);
 588 }
 589
 590 static int br2684_create(void __user * arg)
 591 {
 592         int err;
 593         struct net_device *netdev;
 594         struct br2684_dev *brdev;
 595         struct atm_newif_br2684 ni;
 596         enum br2684_payload payload;
 597
 598         pr_debug("br2684_create\n");
 599
 600         if (copy_from_user(&ni, arg, sizeof ni)) {
 601                 return -EFAULT;
 602         }
 603
 604         if (ni.media & BR2684_FLAG_ROUTED)
 605                 payload = p_routed;
 606         else
 607                 payload = p_bridged;
 608         ni.media &= 0xffff;     /* strip flags */
 609
 610         if (ni.media != BR2684_MEDIA_ETHERNET || ni.mtu != 1500) {
 611                 return -EINVAL;
 612         }
 613
 614         netdev = alloc_netdev(sizeof(struct br2684_dev),
 615                               ni.ifname[0] ? ni.ifname : "nas%d",
 616                               (payload == p_routed) ?
 617                               br2684_setup_routed : br2684_setup);
 618         if (!netdev)
 619                 return -ENOMEM;
 620
 621         brdev = BRPRIV(netdev);
 622
 623         pr_debug("registered netdev %s\n", netdev->name);
 624         /* open, stop, do_ioctl ? */
 625         err = register_netdev(netdev);
 626         if (err < 0) {
 627                 printk(KERN_ERR "br2684_create: register_netdev failed\n");
 628                 free_netdev(netdev);
 629                 return err;
 630         }
 631
 632         write_lock_irq(&devs_lock);
 633         brdev->payload = payload;
 634         brdev->number = list_empty(&br2684_devs) ? 1 :
 635             BRPRIV(list_entry_brdev(br2684_devs.prev))->number + 1;
 636         list_add_tail(&brdev->br2684_devs, &br2684_devs);
 637         write_unlock_irq(&devs_lock);
 638         return 0;
 639 }
 640
 641 /*
 642  * This handles ioctls actually performed on our vcc - we must return
 643  * -ENOIOCTLCMD for any unrecognized ioctl
 644  */
 645 static int br2684_ioctl(struct socket *sock, unsigned int cmd,
 646                         unsigned long arg)
 647 {
 648         struct atm_vcc *atmvcc = ATM_SD(sock);
 649         void __user *argp = (void __user *)arg;
 650         atm_backend_t b;
 651
 652         int err;
 653         switch (cmd) {
 654         case ATM_SETBACKEND:
 655         case ATM_NEWBACKENDIF:
 656                 err = get_user(b, (atm_backend_t __user *) argp);
 657                 if (err)
 658                         return -EFAULT;
 659                 if (b != ATM_BACKEND_BR2684)
 660                         return -ENOIOCTLCMD;
 661                 if (!capable(CAP_NET_ADMIN))
 662                         return -EPERM;
 663                 if (cmd == ATM_SETBACKEND)
 664                         return br2684_regvcc(atmvcc, argp);
 665                 else
 666                         return br2684_create(argp);
 667 #ifdef CONFIG_ATM_BR2684_IPFILTER
 668         case BR2684_SETFILT:
 669                 if (atmvcc->push != br2684_push)
 670                         return -ENOIOCTLCMD;
 671                 if (!capable(CAP_NET_ADMIN))
 672                         return -EPERM;
 673                 err = br2684_setfilt(atmvcc, argp);
 674
 675                 return err;
 676 #endif /* CONFIG_ATM_BR2684_IPFILTER */
 677         }
 678         return -ENOIOCTLCMD;
 679 }
 680
 681 static struct atm_ioctl br2684_ioctl_ops = {
 682         .owner = THIS_MODULE,
 683         .ioctl = br2684_ioctl,
 684 };
 685
 686 #ifdef CONFIG_PROC_FS
 687 static void *br2684_seq_start(struct seq_file *seq, loff_t * pos)
 688         __acquires(devs_lock)
 689 {
 690         read_lock(&devs_lock);
 691         return seq_list_start(&br2684_devs, *pos);
 692 }
 693
 694 static void *br2684_seq_next(struct seq_file *seq, void *v, loff_t * pos)
 695 {
 696         return seq_list_next(v, &br2684_devs, pos);
 697 }
 698
 699 static void br2684_seq_stop(struct seq_file *seq, void *v)
 700         __releases(devs_lock)
 701 {
 702         read_unlock(&devs_lock);
 703 }
 704
 705 static int br2684_seq_show(struct seq_file *seq, void *v)
 706 {
 707         const struct br2684_dev *brdev = list_entry(v, struct br2684_dev,
 708                                                     br2684_devs);
 709         const struct net_device *net_dev = brdev->net_dev;
 710         const struct br2684_vcc *brvcc;
 711
 712         seq_printf(seq, "dev %.16s: num=%d, mac=%pM (%s)\n",
 713                    net_dev->name,
 714                    brdev->number,
 715                    net_dev->dev_addr,
 716                    brdev->mac_was_set ? "set" : "auto");
 717
 718         list_for_each_entry(brvcc, &brdev->brvccs, brvccs) {
 719                 seq_printf(seq, "  vcc %d.%d.%d: encaps=%s payload=%s"
 720                            ", failed copies %u/%u"
 721                            "\n", brvcc->atmvcc->dev->number,
 722                            brvcc->atmvcc->vpi, brvcc->atmvcc->vci,
 723                            (brvcc->encaps == e_llc) ? "LLC" : "VC",
 724                            (brdev->payload == p_bridged) ? "bridged" : "routed",
 725                            brvcc->copies_failed, brvcc->copies_needed);
 726 #ifdef CONFIG_ATM_BR2684_IPFILTER
 727 #define b1(var, byte)   ((u8 *) &brvcc->filter.var)[byte]
 728 #define bs(var)         b1(var, 0), b1(var, 1), b1(var, 2), b1(var, 3)
 729                 if (brvcc->filter.netmask != 0)
 730                         seq_printf(seq, "    filter=%d.%d.%d.%d/"
 731                                    "%d.%d.%d.%d\n", bs(prefix), bs(netmask));
 732 #undef bs
 733 #undef b1
 734 #endif /* CONFIG_ATM_BR2684_IPFILTER */
 735         }
 736         return 0;
 737 }
 738
 739 static const struct seq_operations br2684_seq_ops = {
 740         .start = br2684_seq_start,
 741         .next = br2684_seq_next,
 742         .stop = br2684_seq_stop,
 743         .show = br2684_seq_show,
 744 };
 745
 746 static int br2684_proc_open(struct inode *inode, struct file *file)
 747 {
 748         return seq_open(file, &br2684_seq_ops);
 749 }
 750
 751 static const struct file_operations br2684_proc_ops = {
 752         .owner = THIS_MODULE,
 753         .open = br2684_proc_open,
 754         .read = seq_read,
 755         .llseek = seq_lseek,
 756         .release = seq_release,
 757 };
 758
 759 extern struct proc_dir_entry *atm_proc_root;    /* from proc.c */
 760 #endif /* CONFIG_PROC_FS */
 761
 762 static int __init br2684_init(void)
 763 {
 764 #ifdef CONFIG_PROC_FS
 765         struct proc_dir_entry *p;
 766         p = proc_create("br2684", 0, atm_proc_root, &br2684_proc_ops);
 767         if (p == NULL)
 768                 return -ENOMEM;
 769 #endif
 770         register_atm_ioctl(&br2684_ioctl_ops);
 771         return 0;
 772 }
 773
 774 static void __exit br2684_exit(void)
 775 {
 776         struct net_device *net_dev;
 777         struct br2684_dev *brdev;
 778         struct br2684_vcc *brvcc;
 779         deregister_atm_ioctl(&br2684_ioctl_ops);
 780
 781 #ifdef CONFIG_PROC_FS
 782         remove_proc_entry("br2684", atm_proc_root);
 783 #endif
 784
 785         while (!list_empty(&br2684_devs)) {
 786                 net_dev = list_entry_brdev(br2684_devs.next);
 787                 brdev = BRPRIV(net_dev);
 788                 while (!list_empty(&brdev->brvccs)) {
 789                         brvcc = list_entry_brvcc(brdev->brvccs.next);
 790                         br2684_close_vcc(brvcc);
 791                 }
 792
 793                 list_del(&brdev->br2684_devs);
 794                 unregister_netdev(net_dev);
 795                 free_netdev(net_dev);
 796         }
 797 }
 798
 799 module_init(br2684_init);
 800 module_exit(br2684_exit);
 801
 802 MODULE_AUTHOR("Marcell GAL");
 803 MODULE_DESCRIPTION("RFC2684 bridged protocols over ATM/AAL5");
 804 MODULE_LICENSE("GPL");