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