net/atm/br2684.c

   1 /*
   2  * Ethernet netdevice using ATM AAL5 as underlying carrier
   3  * (RFC1483 obsoleted by RFC2684) for Linux
   4  *
   5  * Authors: Marcell GAL, 2000, XDSL Ltd, Hungary
   6  *          Eric Kinzie, 2006-2007, US Naval Research Laboratory
   7  */
   8
   9 #define pr_fmt(fmt) KBUILD_MODNAME ":%s: " fmt, __func__
  10
  11 #include <linux/module.h>
  12 #include <linux/init.h>
  13 #include <linux/kernel.h>
  14 #include <linux/list.h>
  15 #include <linux/netdevice.h>
  16 #include <linux/skbuff.h>
  17 #include <linux/etherdevice.h>
  18 #include <linux/rtnetlink.h>
  19 #include <linux/ip.h>
  20 #include <linux/uaccess.h>
  21 #include <linux/slab.h>
  22 #include <net/arp.h>
  23 #include <linux/atm.h>
  24 #include <linux/atmdev.h>
  25 #include <linux/capability.h>
  26 #include <linux/seq_file.h>
  27
  28 #include <linux/atmbr2684.h>
  29
  30 #include "common.h"
  31
  32 static void skb_debug(const struct sk_buff *skb)
  33 {
  34 #ifdef SKB_DEBUG
  35 #define NUM2PRINT 50
  36         print_hex_dump(KERN_DEBUG, "br2684: skb: ", DUMP_OFFSET,
  37                        16, 1, skb->data, min(NUM2PRINT, skb->len), true);
  38 #endif
  39 }
  40
  41 #define BR2684_ETHERTYPE_LEN    2
  42 #define BR2684_PAD_LEN          2
  43
  44 #define LLC             0xaa, 0xaa, 0x03
  45 #define SNAP_BRIDGED    0x00, 0x80, 0xc2
  46 #define SNAP_ROUTED     0x00, 0x00, 0x00
  47 #define PID_ETHERNET    0x00, 0x07
  48 #define ETHERTYPE_IPV4  0x08, 0x00
  49 #define ETHERTYPE_IPV6  0x86, 0xdd
  50 #define PAD_BRIDGED     0x00, 0x00
  51
  52 static const unsigned char ethertype_ipv4[] = { ETHERTYPE_IPV4 };
  53 static const unsigned char ethertype_ipv6[] = { ETHERTYPE_IPV6 };
  54 static const unsigned char llc_oui_pid_pad[] =
  55                         { LLC, SNAP_BRIDGED, PID_ETHERNET, PAD_BRIDGED };
  56 static const unsigned char llc_oui_ipv4[] = { LLC, SNAP_ROUTED, ETHERTYPE_IPV4 };
  57 static const unsigned char llc_oui_ipv6[] = { LLC, SNAP_ROUTED, ETHERTYPE_IPV6 };
  58
  59 enum br2684_encaps {
  60         e_vc = BR2684_ENCAPS_VC,
  61         e_llc = BR2684_ENCAPS_LLC,
  62 };
  63
  64 struct br2684_vcc {
  65         struct atm_vcc *atmvcc;
  66         struct net_device *device;
  67         /* keep old push, pop functions for chaining */
  68         void (*old_push)(struct atm_vcc *vcc, struct sk_buff *skb);
  69         void (*old_pop)(struct atm_vcc *vcc, struct sk_buff *skb);
  70         enum br2684_encaps encaps;
  71         struct list_head brvccs;
  72 #ifdef CONFIG_ATM_BR2684_IPFILTER
  73         struct br2684_filter filter;
  74 #endif /* CONFIG_ATM_BR2684_IPFILTER */
  75         unsigned copies_needed, copies_failed;
  76 };
  77
  78 struct br2684_dev {
  79         struct net_device *net_dev;
  80         struct list_head br2684_devs;
  81         int number;
  82         struct list_head brvccs;        /* one device <=> one vcc (before xmas) */
  83         int mac_was_set;
  84         enum br2684_payload payload;
  85 };
  86
  87 /*
  88  * This lock should be held for writing any time the list of devices or
  89  * their attached vcc's could be altered.  It should be held for reading
  90  * any time these are being queried.  Note that we sometimes need to
  91  * do read-locking under interrupt context, so write locking must block
  92  * the current CPU's interrupts
  93  */
  94 static DEFINE_RWLOCK(devs_lock);
  95
  96 static LIST_HEAD(br2684_devs);
  97
  98 static inline struct br2684_dev *BRPRIV(const struct net_device *net_dev)
  99 {
 100         return (struct br2684_dev *)netdev_priv(net_dev);
 101 }
 102
 103 static inline struct net_device *list_entry_brdev(const struct list_head *le)
 104 {
 105         return list_entry(le, struct br2684_dev, br2684_devs)->net_dev;
 106 }
 107
 108 static inline struct br2684_vcc *BR2684_VCC(const struct atm_vcc *atmvcc)
 109 {
 110         return (struct br2684_vcc *)(atmvcc->user_back);
 111 }
 112
 113 static inline struct br2684_vcc *list_entry_brvcc(const struct list_head *le)
 114 {
 115         return list_entry(le, struct br2684_vcc, brvccs);
 116 }
 117
 118 /* Caller should hold read_lock(&devs_lock) */
 119 static struct net_device *br2684_find_dev(const struct br2684_if_spec *s)
 120 {
 121         struct list_head *lh;
 122         struct net_device *net_dev;
 123         switch (s->method) {
 124         case BR2684_FIND_BYNUM:
 125                 list_for_each(lh, &br2684_devs) {
 126                         net_dev = list_entry_brdev(lh);
 127                         if (BRPRIV(net_dev)->number == s->spec.devnum)
 128                                 return net_dev;
 129                 }
 130                 break;
 131         case BR2684_FIND_BYIFNAME:
 132                 list_for_each(lh, &br2684_devs) {
 133                         net_dev = list_entry_brdev(lh);
 134                         if (!strncmp(net_dev->name, s->spec.ifname, IFNAMSIZ))
 135                                 return net_dev;
 136                 }
 137                 break;
 138         }
 139         return NULL;
 140 }
 141
 142 static int atm_dev_event(struct notifier_block *this, unsigned long event,
 143                  void *arg)
 144 {
 145         struct atm_dev *atm_dev = arg;
 146         struct list_head *lh;
 147         struct net_device *net_dev;
 148         struct br2684_vcc *brvcc;
 149         struct atm_vcc *atm_vcc;
 150         unsigned long flags;
 151
 152         pr_debug("event=%ld dev=%p\n", event, atm_dev);
 153
 154         read_lock_irqsave(&devs_lock, flags);
 155         list_for_each(lh, &br2684_devs) {
 156                 net_dev = list_entry_brdev(lh);
 157
 158                 list_for_each_entry(brvcc, &BRPRIV(net_dev)->brvccs, brvccs) {
 159                         atm_vcc = brvcc->atmvcc;
 160                         if (atm_vcc && brvcc->atmvcc->dev == atm_dev) {
 161
 162                                 if (atm_vcc->dev->signal == ATM_PHY_SIG_LOST)
 163                                         netif_carrier_off(net_dev);
 164                                 else
 165                                         netif_carrier_on(net_dev);
 166
 167                         }
 168                 }
 169         }
 170         read_unlock_irqrestore(&devs_lock, flags);
 171
 172         return NOTIFY_DONE;
 173 }
 174
 175 static struct notifier_block atm_dev_notifier = {
 176         .notifier_call = atm_dev_event,
 177 };
 178
 179 /* chained vcc->pop function.  Check if we should wake the netif_queue */
 180 static void br2684_pop(struct atm_vcc *vcc, struct sk_buff *skb)
 181 {
 182         struct br2684_vcc *brvcc = BR2684_VCC(vcc);
 183         struct net_device *net_dev = skb->dev;
 184
 185         pr_debug("(vcc %p ; net_dev %p )\n", vcc, net_dev);
 186         brvcc->old_pop(vcc, skb);
 187
 188         if (!net_dev)
 189                 return;
 190
 191         if (atm_may_send(vcc, 0))
 192                 netif_wake_queue(net_dev);
 193
 194 }
 195 /*
 196  * Send a packet out a particular vcc.  Not to useful right now, but paves
 197  * the way for multiple vcc's per itf.  Returns true if we can send,
 198  * otherwise false
 199  */
 200 static int br2684_xmit_vcc(struct sk_buff *skb, struct net_device *dev,
 201                            struct br2684_vcc *brvcc)
 202 {
 203         struct br2684_dev *brdev = BRPRIV(dev);
 204         struct atm_vcc *atmvcc;
 205         int minheadroom = (brvcc->encaps == e_llc) ? 10 : 2;
 206
 207         if (skb_headroom(skb) < minheadroom) {
 208                 struct sk_buff *skb2 = skb_realloc_headroom(skb, minheadroom);
 209                 brvcc->copies_needed++;
 210                 dev_kfree_skb(skb);
 211                 if (skb2 == NULL) {
 212                         brvcc->copies_failed++;
 213                         return 0;
 214                 }
 215                 skb = skb2;
 216         }
 217
 218         if (brvcc->encaps == e_llc) {
 219                 if (brdev->payload == p_bridged) {
 220                         skb_push(skb, sizeof(llc_oui_pid_pad));
 221                         skb_copy_to_linear_data(skb, llc_oui_pid_pad,
 222                                                 sizeof(llc_oui_pid_pad));
 223                 } else if (brdev->payload == p_routed) {
 224                         unsigned short prot = ntohs(skb->protocol);
 225
 226                         skb_push(skb, sizeof(llc_oui_ipv4));
 227                         switch (prot) {
 228                         case ETH_P_IP:
 229                                 skb_copy_to_linear_data(skb, llc_oui_ipv4,
 230                                                         sizeof(llc_oui_ipv4));
 231                                 break;
 232                         case ETH_P_IPV6:
 233                                 skb_copy_to_linear_data(skb, llc_oui_ipv6,
 234                                                         sizeof(llc_oui_ipv6));
 235                                 break;
 236                         default:
 237                                 dev_kfree_skb(skb);
 238                                 return 0;
 239                         }
 240                 }
 241         } else { /* e_vc */
 242                 if (brdev->payload == p_bridged) {
 243                         skb_push(skb, 2);
 244                         memset(skb->data, 0, 2);
 245                 } else { /* p_routed */
 246                         skb_pull(skb, ETH_HLEN);
 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         atmvcc->send(atmvcc, skb);
 258
 259         if (!atm_may_send(atmvcc, 0)) {
 260                 netif_stop_queue(brvcc->device);
 261                 /*check for race with br2684_pop*/
 262                 if (atm_may_send(atmvcc, 0))
 263                         netif_start_queue(brvcc->device);
 264         }
 265
 266         return 1;
 267 }
 268
 269 static inline struct br2684_vcc *pick_outgoing_vcc(const struct sk_buff *skb,
 270                                                    const struct br2684_dev *brdev)
 271 {
 272         return list_empty(&brdev->brvccs) ? NULL : list_entry_brvcc(brdev->brvccs.next);        /* 1 vcc/dev right now */
 273 }
 274
 275 static netdev_tx_t br2684_start_xmit(struct sk_buff *skb,
 276                                      struct net_device *dev)
 277 {
 278         struct br2684_dev *brdev = BRPRIV(dev);
 279         struct br2684_vcc *brvcc;
 280
 281         pr_debug("skb_dst(skb)=%p\n", skb_dst(skb));
 282         read_lock(&devs_lock);
 283         brvcc = pick_outgoing_vcc(skb, brdev);
 284         if (brvcc == NULL) {
 285                 pr_debug("no vcc attached to dev %s\n", dev->name);
 286                 dev->stats.tx_errors++;
 287                 dev->stats.tx_carrier_errors++;
 288                 /* netif_stop_queue(dev); */
 289                 dev_kfree_skb(skb);
 290                 read_unlock(&devs_lock);
 291                 return NETDEV_TX_OK;
 292         }
 293         if (!br2684_xmit_vcc(skb, dev, brvcc)) {
 294                 /*
 295                  * We should probably use netif_*_queue() here, but that
 296                  * involves added complication.  We need to walk before
 297                  * we can run.
 298                  *
 299                  * Don't free here! this pointer might be no longer valid!
 300                  */
 301                 dev->stats.tx_errors++;
 302                 dev->stats.tx_fifo_errors++;
 303         }
 304         read_unlock(&devs_lock);
 305         return NETDEV_TX_OK;
 306 }
 307
 308 /*
 309  * We remember when the MAC gets set, so we don't override it later with
 310  * the ESI of the ATM card of the first VC
 311  */
 312 static int br2684_mac_addr(struct net_device *dev, void *p)
 313 {
 314         int err = eth_mac_addr(dev, p);
 315         if (!err)
 316                 BRPRIV(dev)->mac_was_set = 1;
 317         return err;
 318 }
 319
 320 #ifdef CONFIG_ATM_BR2684_IPFILTER
 321 /* this IOCTL is experimental. */
 322 static int br2684_setfilt(struct atm_vcc *atmvcc, void __user * arg)
 323 {
 324         struct br2684_vcc *brvcc;
 325         struct br2684_filter_set fs;
 326
 327         if (copy_from_user(&fs, arg, sizeof fs))
 328                 return -EFAULT;
 329         if (fs.ifspec.method != BR2684_FIND_BYNOTHING) {
 330                 /*
 331                  * This is really a per-vcc thing, but we can also search
 332                  * by device.
 333                  */
 334                 struct br2684_dev *brdev;
 335                 read_lock(&devs_lock);
 336                 brdev = BRPRIV(br2684_find_dev(&fs.ifspec));
 337                 if (brdev == NULL || list_empty(&brdev->brvccs) ||
 338                     brdev->brvccs.next != brdev->brvccs.prev)   /* >1 VCC */
 339                         brvcc = NULL;
 340                 else
 341                         brvcc = list_entry_brvcc(brdev->brvccs.next);
 342                 read_unlock(&devs_lock);
 343                 if (brvcc == NULL)
 344                         return -ESRCH;
 345         } else
 346                 brvcc = BR2684_VCC(atmvcc);
 347         memcpy(&brvcc->filter, &fs.filter, sizeof(brvcc->filter));
 348         return 0;
 349 }
 350
 351 /* Returns 1 if packet should be dropped */
 352 static inline int
 353 packet_fails_filter(__be16 type, struct br2684_vcc *brvcc, struct sk_buff *skb)
 354 {
 355         if (brvcc->filter.netmask == 0)
 356                 return 0;       /* no filter in place */
 357         if (type == htons(ETH_P_IP) &&
 358             (((struct iphdr *)(skb->data))->daddr & brvcc->filter.
 359              netmask) == brvcc->filter.prefix)
 360                 return 0;
 361         if (type == htons(ETH_P_ARP))
 362                 return 0;
 363         /*
 364          * TODO: we should probably filter ARPs too.. don't want to have
 365          * them returning values that don't make sense, or is that ok?
 366          */
 367         return 1;               /* drop */
 368 }
 369 #endif /* CONFIG_ATM_BR2684_IPFILTER */
 370
 371 static void br2684_close_vcc(struct br2684_vcc *brvcc)
 372 {
 373         pr_debug("removing VCC %p from dev %p\n", brvcc, brvcc->device);
 374         write_lock_irq(&devs_lock);
 375         list_del(&brvcc->brvccs);
 376         write_unlock_irq(&devs_lock);
 377         brvcc->atmvcc->user_back = NULL;        /* what about vcc->recvq ??? */
 378         brvcc->old_push(brvcc->atmvcc, NULL);   /* pass on the bad news */
 379         kfree(brvcc);
 380         module_put(THIS_MODULE);
 381 }
 382
 383 /* when AAL5 PDU comes in: */
 384 static void br2684_push(struct atm_vcc *atmvcc, struct sk_buff *skb)
 385 {
 386         struct br2684_vcc *brvcc = BR2684_VCC(atmvcc);
 387         struct net_device *net_dev = brvcc->device;
 388         struct br2684_dev *brdev = BRPRIV(net_dev);
 389
 390         pr_debug("\n");
 391
 392         if (unlikely(skb == NULL)) {
 393                 /* skb==NULL means VCC is being destroyed */
 394                 br2684_close_vcc(brvcc);
 395                 if (list_empty(&brdev->brvccs)) {
 396                         write_lock_irq(&devs_lock);
 397                         list_del(&brdev->br2684_devs);
 398                         write_unlock_irq(&devs_lock);
 399                         unregister_netdev(net_dev);
 400                         free_netdev(net_dev);
 401                 }
 402                 read_lock_irq(&devs_lock);
 403                 if (list_empty(&br2684_devs)) {
 404                         /* last br2684 device */
 405                         unregister_atmdevice_notifier(&atm_dev_notifier);
 406                 }
 407                 read_unlock_irq(&devs_lock);
 408                 return;
 409         }
 410
 411         skb_debug(skb);
 412         atm_return(atmvcc, skb->truesize);
 413         pr_debug("skb from brdev %p\n", brdev);
 414         if (brvcc->encaps == e_llc) {
 415
 416                 if (skb->len > 7 && skb->data[7] == 0x01)
 417                         __skb_trim(skb, skb->len - 4);
 418
 419                 /* accept packets that have "ipv[46]" in the snap header */
 420                 if ((skb->len >= (sizeof(llc_oui_ipv4))) &&
 421                     (memcmp(skb->data, llc_oui_ipv4,
 422                             sizeof(llc_oui_ipv4) - BR2684_ETHERTYPE_LEN) == 0)) {
 423                         if (memcmp(skb->data + 6, ethertype_ipv6,
 424                                    sizeof(ethertype_ipv6)) == 0)
 425                                 skb->protocol = htons(ETH_P_IPV6);
 426                         else if (memcmp(skb->data + 6, ethertype_ipv4,
 427                                         sizeof(ethertype_ipv4)) == 0)
 428                                 skb->protocol = htons(ETH_P_IP);
 429                         else
 430                                 goto error;
 431                         skb_pull(skb, sizeof(llc_oui_ipv4));
 432                         skb_reset_network_header(skb);
 433                         skb->pkt_type = PACKET_HOST;
 434                 /*
 435                  * Let us waste some time for checking the encapsulation.
 436                  * Note, that only 7 char is checked so frames with a valid FCS
 437                  * are also accepted (but FCS is not checked of course).
 438                  */
 439                 } else if ((skb->len >= sizeof(llc_oui_pid_pad)) &&
 440                            (memcmp(skb->data, llc_oui_pid_pad, 7) == 0)) {
 441                         skb_pull(skb, sizeof(llc_oui_pid_pad));
 442                         skb->protocol = eth_type_trans(skb, net_dev);
 443                 } else
 444                         goto error;
 445
 446         } else { /* e_vc */
 447                 if (brdev->payload == p_routed) {
 448                         struct iphdr *iph;
 449
 450                         skb_reset_network_header(skb);
 451                         iph = ip_hdr(skb);
 452                         if (iph->version == 4)
 453                                 skb->protocol = htons(ETH_P_IP);
 454                         else if (iph->version == 6)
 455                                 skb->protocol = htons(ETH_P_IPV6);
 456                         else
 457                                 goto error;
 458                         skb->pkt_type = PACKET_HOST;
 459                 } else { /* p_bridged */
 460                         /* first 2 chars should be 0 */
 461                         if (*((u16 *) (skb->data)) != 0)
 462                                 goto error;
 463                         skb_pull(skb, BR2684_PAD_LEN);
 464                         skb->protocol = eth_type_trans(skb, net_dev);
 465                 }
 466         }
 467
 468 #ifdef CONFIG_ATM_BR2684_IPFILTER
 469         if (unlikely(packet_fails_filter(skb->protocol, brvcc, skb)))
 470                 goto dropped;
 471 #endif /* CONFIG_ATM_BR2684_IPFILTER */
 472         skb->dev = net_dev;
 473         ATM_SKB(skb)->vcc = atmvcc;     /* needed ? */
 474         pr_debug("received packet's protocol: %x\n", ntohs(skb->protocol));
 475         skb_debug(skb);
 476         /* sigh, interface is down? */
 477         if (unlikely(!(net_dev->flags & IFF_UP)))
 478                 goto dropped;
 479         net_dev->stats.rx_packets++;
 480         net_dev->stats.rx_bytes += skb->len;
 481         memset(ATM_SKB(skb), 0, sizeof(struct atm_skb_data));
 482         netif_rx(skb);
 483         return;
 484
 485 dropped:
 486         net_dev->stats.rx_dropped++;
 487         goto free_skb;
 488 error:
 489         net_dev->stats.rx_errors++;
 490 free_skb:
 491         dev_kfree_skb(skb);
 492 }
 493
 494 /*
 495  * Assign a vcc to a dev
 496  * Note: we do not have explicit unassign, but look at _push()
 497  */
 498 static int br2684_regvcc(struct atm_vcc *atmvcc, void __user * arg)
 499 {
 500         struct sk_buff_head queue;
 501         int err;
 502         struct br2684_vcc *brvcc;
 503         struct sk_buff *skb, *tmp;
 504         struct sk_buff_head *rq;
 505         struct br2684_dev *brdev;
 506         struct net_device *net_dev;
 507         struct atm_backend_br2684 be;
 508         unsigned long flags;
 509
 510         if (copy_from_user(&be, arg, sizeof be))
 511                 return -EFAULT;
 512         brvcc = kzalloc(sizeof(struct br2684_vcc), GFP_KERNEL);
 513         if (!brvcc)
 514                 return -ENOMEM;
 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-existant 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         __skb_queue_head_init(&queue);
 562         rq = &sk_atm(atmvcc)->sk_receive_queue;
 563
 564         spin_lock_irqsave(&rq->lock, flags);
 565         skb_queue_splice_init(rq, &queue);
 566         spin_unlock_irqrestore(&rq->lock, flags);
 567
 568         skb_queue_walk_safe(&queue, skb, tmp) {
 569                 struct net_device *dev = skb->dev;
 570
 571                 dev->stats.rx_bytes -= skb->len;
 572                 dev->stats.rx_packets--;
 573
 574                 br2684_push(atmvcc, skb);
 575         }
 576
 577         /* initialize netdev carrier state */
 578         if (atmvcc->dev->signal == ATM_PHY_SIG_LOST)
 579                 netif_carrier_off(net_dev);
 580         else
 581                 netif_carrier_on(net_dev);
 582
 583         __module_get(THIS_MODULE);
 584         return 0;
 585
 586 error:
 587         write_unlock_irq(&devs_lock);
 588         kfree(brvcc);
 589         return err;
 590 }
 591
 592 static const struct net_device_ops br2684_netdev_ops = {
 593         .ndo_start_xmit         = br2684_start_xmit,
 594         .ndo_set_mac_address    = br2684_mac_addr,
 595         .ndo_change_mtu         = eth_change_mtu,
 596         .ndo_validate_addr      = eth_validate_addr,
 597 };
 598
 599 static const struct net_device_ops br2684_netdev_ops_routed = {
 600         .ndo_start_xmit         = br2684_start_xmit,
 601         .ndo_set_mac_address    = br2684_mac_addr,
 602         .ndo_change_mtu         = eth_change_mtu
 603 };
 604
 605 static void br2684_setup(struct net_device *netdev)
 606 {
 607         struct br2684_dev *brdev = BRPRIV(netdev);
 608
 609         ether_setup(netdev);
 610         brdev->net_dev = netdev;
 611
 612         netdev->netdev_ops = &br2684_netdev_ops;
 613
 614         INIT_LIST_HEAD(&brdev->brvccs);
 615 }
 616
 617 static void br2684_setup_routed(struct net_device *netdev)
 618 {
 619         struct br2684_dev *brdev = BRPRIV(netdev);
 620
 621         brdev->net_dev = netdev;
 622         netdev->hard_header_len = 0;
 623         netdev->netdev_ops = &br2684_netdev_ops_routed;
 624         netdev->addr_len = 0;
 625         netdev->mtu = 1500;
 626         netdev->type = ARPHRD_PPP;
 627         netdev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
 628         netdev->tx_queue_len = 100;
 629         INIT_LIST_HEAD(&brdev->brvccs);
 630 }
 631
 632 static int br2684_create(void __user *arg)
 633 {
 634         int err;
 635         struct net_device *netdev;
 636         struct br2684_dev *brdev;
 637         struct atm_newif_br2684 ni;
 638         enum br2684_payload payload;
 639
 640         pr_debug("\n");
 641
 642         if (copy_from_user(&ni, arg, sizeof ni))
 643                 return -EFAULT;
 644
 645         if (ni.media & BR2684_FLAG_ROUTED)
 646                 payload = p_routed;
 647         else
 648                 payload = p_bridged;
 649         ni.media &= 0xffff;     /* strip flags */
 650
 651         if (ni.media != BR2684_MEDIA_ETHERNET || ni.mtu != 1500)
 652                 return -EINVAL;
 653
 654         netdev = alloc_netdev(sizeof(struct br2684_dev),
 655                               ni.ifname[0] ? ni.ifname : "nas%d",
 656                               (payload == p_routed) ?
 657                               br2684_setup_routed : br2684_setup);
 658         if (!netdev)
 659                 return -ENOMEM;
 660
 661         brdev = BRPRIV(netdev);
 662
 663         pr_debug("registered netdev %s\n", netdev->name);
 664         /* open, stop, do_ioctl ? */
 665         err = register_netdev(netdev);
 666         if (err < 0) {
 667                 pr_err("register_netdev failed\n");
 668                 free_netdev(netdev);
 669                 return err;
 670         }
 671
 672         write_lock_irq(&devs_lock);
 673
 674         brdev->payload = payload;
 675
 676         if (list_empty(&br2684_devs)) {
 677                 /* 1st br2684 device */
 678                 register_atmdevice_notifier(&atm_dev_notifier);
 679                 brdev->number = 1;
 680         } else
 681                 brdev->number = BRPRIV(list_entry_brdev(br2684_devs.prev))->number + 1;
 682
 683         list_add_tail(&brdev->br2684_devs, &br2684_devs);
 684         write_unlock_irq(&devs_lock);
 685         return 0;
 686 }
 687
 688 /*
 689  * This handles ioctls actually performed on our vcc - we must return
 690  * -ENOIOCTLCMD for any unrecognized ioctl
 691  */
 692 static int br2684_ioctl(struct socket *sock, unsigned int cmd,
 693                         unsigned long arg)
 694 {
 695         struct atm_vcc *atmvcc = ATM_SD(sock);
 696         void __user *argp = (void __user *)arg;
 697         atm_backend_t b;
 698
 699         int err;
 700         switch (cmd) {
 701         case ATM_SETBACKEND:
 702         case ATM_NEWBACKENDIF:
 703                 err = get_user(b, (atm_backend_t __user *) argp);
 704                 if (err)
 705                         return -EFAULT;
 706                 if (b != ATM_BACKEND_BR2684)
 707                         return -ENOIOCTLCMD;
 708                 if (!capable(CAP_NET_ADMIN))
 709                         return -EPERM;
 710                 if (cmd == ATM_SETBACKEND)
 711                         return br2684_regvcc(atmvcc, argp);
 712                 else
 713                         return br2684_create(argp);
 714 #ifdef CONFIG_ATM_BR2684_IPFILTER
 715         case BR2684_SETFILT:
 716                 if (atmvcc->push != br2684_push)
 717                         return -ENOIOCTLCMD;
 718                 if (!capable(CAP_NET_ADMIN))
 719                         return -EPERM;
 720                 err = br2684_setfilt(atmvcc, argp);
 721
 722                 return err;
 723 #endif /* CONFIG_ATM_BR2684_IPFILTER */
 724         }
 725         return -ENOIOCTLCMD;
 726 }
 727
 728 static struct atm_ioctl br2684_ioctl_ops = {
 729         .owner = THIS_MODULE,
 730         .ioctl = br2684_ioctl,
 731 };
 732
 733 #ifdef CONFIG_PROC_FS
 734 static void *br2684_seq_start(struct seq_file *seq, loff_t * pos)
 735         __acquires(devs_lock)
 736 {
 737         read_lock(&devs_lock);
 738         return seq_list_start(&br2684_devs, *pos);
 739 }
 740
 741 static void *br2684_seq_next(struct seq_file *seq, void *v, loff_t * pos)
 742 {
 743         return seq_list_next(v, &br2684_devs, pos);
 744 }
 745
 746 static void br2684_seq_stop(struct seq_file *seq, void *v)
 747         __releases(devs_lock)
 748 {
 749         read_unlock(&devs_lock);
 750 }
 751
 752 static int br2684_seq_show(struct seq_file *seq, void *v)
 753 {
 754         const struct br2684_dev *brdev = list_entry(v, struct br2684_dev,
 755                                                     br2684_devs);
 756         const struct net_device *net_dev = brdev->net_dev;
 757         const struct br2684_vcc *brvcc;
 758
 759         seq_printf(seq, "dev %.16s: num=%d, mac=%pM (%s)\n",
 760                    net_dev->name,
 761                    brdev->number,
 762                    net_dev->dev_addr,
 763                    brdev->mac_was_set ? "set" : "auto");
 764
 765         list_for_each_entry(brvcc, &brdev->brvccs, brvccs) {
 766                 seq_printf(seq, "  vcc %d.%d.%d: encaps=%s payload=%s"
 767                            ", failed copies %u/%u"
 768                            "\n", brvcc->atmvcc->dev->number,
 769                            brvcc->atmvcc->vpi, brvcc->atmvcc->vci,
 770                            (brvcc->encaps == e_llc) ? "LLC" : "VC",
 771                            (brdev->payload == p_bridged) ? "bridged" : "routed",
 772                            brvcc->copies_failed, brvcc->copies_needed);
 773 #ifdef CONFIG_ATM_BR2684_IPFILTER
 774 #define b1(var, byte)   ((u8 *) &brvcc->filter.var)[byte]
 775 #define bs(var)         b1(var, 0), b1(var, 1), b1(var, 2), b1(var, 3)
 776                 if (brvcc->filter.netmask != 0)
 777                         seq_printf(seq, "    filter=%d.%d.%d.%d/"
 778                                    "%d.%d.%d.%d\n", bs(prefix), bs(netmask));
 779 #undef bs
 780 #undef b1
 781 #endif /* CONFIG_ATM_BR2684_IPFILTER */
 782         }
 783         return 0;
 784 }
 785
 786 static const struct seq_operations br2684_seq_ops = {
 787         .start = br2684_seq_start,
 788         .next = br2684_seq_next,
 789         .stop = br2684_seq_stop,
 790         .show = br2684_seq_show,
 791 };
 792
 793 static int br2684_proc_open(struct inode *inode, struct file *file)
 794 {
 795         return seq_open(file, &br2684_seq_ops);
 796 }
 797
 798 static const struct file_operations br2684_proc_ops = {
 799         .owner = THIS_MODULE,
 800         .open = br2684_proc_open,
 801         .read = seq_read,
 802         .llseek = seq_lseek,
 803         .release = seq_release,
 804 };
 805
 806 extern struct proc_dir_entry *atm_proc_root;    /* from proc.c */
 807 #endif /* CONFIG_PROC_FS */
 808
 809 static int __init br2684_init(void)
 810 {
 811 #ifdef CONFIG_PROC_FS
 812         struct proc_dir_entry *p;
 813         p = proc_create("br2684", 0, atm_proc_root, &br2684_proc_ops);
 814         if (p == NULL)
 815                 return -ENOMEM;
 816 #endif
 817         register_atm_ioctl(&br2684_ioctl_ops);
 818         return 0;
 819 }
 820
 821 static void __exit br2684_exit(void)
 822 {
 823         struct net_device *net_dev;
 824         struct br2684_dev *brdev;
 825         struct br2684_vcc *brvcc;
 826         deregister_atm_ioctl(&br2684_ioctl_ops);
 827
 828 #ifdef CONFIG_PROC_FS
 829         remove_proc_entry("br2684", atm_proc_root);
 830 #endif
 831
 832
 833         /* if not already empty */
 834         if (!list_empty(&br2684_devs))
 835                 unregister_atmdevice_notifier(&atm_dev_notifier);
 836
 837         while (!list_empty(&br2684_devs)) {
 838                 net_dev = list_entry_brdev(br2684_devs.next);
 839                 brdev = BRPRIV(net_dev);
 840                 while (!list_empty(&brdev->brvccs)) {
 841                         brvcc = list_entry_brvcc(brdev->brvccs.next);
 842                         br2684_close_vcc(brvcc);
 843                 }
 844
 845                 list_del(&brdev->br2684_devs);
 846                 unregister_netdev(net_dev);
 847                 free_netdev(net_dev);
 848         }
 849 }
 850
 851 module_init(br2684_init);
 852 module_exit(br2684_exit);
 853
 854 MODULE_AUTHOR("Marcell GAL");
 855 MODULE_DESCRIPTION("RFC2684 bridged protocols over ATM/AAL5");
 856 MODULE_LICENSE("GPL");