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