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