net/atm/br2684.c

   1 /*
   2  * Ethernet netdevice using ATM AAL5 as underlying carrier
   3  * (RFC1483 obsoleted by RFC2684) for Linux
   4  *
   5  * Authors: Marcell GAL, 2000, XDSL Ltd, Hungary
   6  *          Eric Kinzie, 2006-2007, US Naval Research Laboratory
   7  */
   8
   9 #include <linux/module.h>
  10 #include <linux/init.h>
  11 #include <linux/kernel.h>
  12 #include <linux/list.h>
  13 #include <linux/netdevice.h>
  14 #include <linux/skbuff.h>
  15 #include <linux/etherdevice.h>
  16 #include <linux/rtnetlink.h>
  17 #include <linux/ip.h>
  18 #include <asm/uaccess.h>
  19 #include <net/arp.h>
  20 #include <linux/atm.h>
  21 #include <linux/atmdev.h>
  22 #include <linux/capability.h>
  23 #include <linux/seq_file.h>
  24
  25 #include <linux/atmbr2684.h>
  26
  27 #include "common.h"
  28
  29 #ifdef SKB_DEBUG
  30 static void skb_debug(const struct sk_buff *skb)
  31 {
  32 #define NUM2PRINT 50
  33         char buf[NUM2PRINT * 3 + 1];    /* 3 chars per byte */
  34         int i = 0;
  35         for (i = 0; i < skb->len && i < NUM2PRINT; i++) {
  36                 sprintf(buf + i * 3, "%2.2x ", 0xff & skb->data[i]);
  37         }
  38         printk(KERN_DEBUG "br2684: skb: %s\n", buf);
  39 }
  40 #else
  41 #define skb_debug(skb)  do {} while (0)
  42 #endif
  43
  44 #define BR2684_ETHERTYPE_LEN    2
  45 #define BR2684_PAD_LEN          2
  46
  47 #define LLC             0xaa, 0xaa, 0x03
  48 #define SNAP_BRIDGED    0x00, 0x80, 0xc2
  49 #define SNAP_ROUTED     0x00, 0x00, 0x00
  50 #define PID_ETHERNET    0x00, 0x07
  51 #define ETHERTYPE_IPV4  0x08, 0x00
  52 #define ETHERTYPE_IPV6  0x86, 0xdd
  53 #define PAD_BRIDGED     0x00, 0x00
  54
  55 static const unsigned char ethertype_ipv4[] = { ETHERTYPE_IPV4 };
  56 static const unsigned char ethertype_ipv6[] = { ETHERTYPE_IPV6 };
  57 static const unsigned char llc_oui_pid_pad[] =
  58                         { LLC, SNAP_BRIDGED, PID_ETHERNET, PAD_BRIDGED };
  59 static const unsigned char llc_oui_ipv4[] = { LLC, SNAP_ROUTED, ETHERTYPE_IPV4 };
  60 static const unsigned char llc_oui_ipv6[] = { LLC, SNAP_ROUTED, ETHERTYPE_IPV6 };
  61
  62 enum br2684_encaps {
  63         e_vc = BR2684_ENCAPS_VC,
  64         e_llc = BR2684_ENCAPS_LLC,
  65 };
  66
  67 struct br2684_vcc {
  68         struct atm_vcc *atmvcc;
  69         struct net_device *device;
  70         /* keep old push, pop functions for chaining */
  71         void (*old_push) (struct atm_vcc * vcc, struct sk_buff * skb);
  72         /* void (*old_pop)(struct atm_vcc *vcc, struct sk_buff *skb); */
  73         enum br2684_encaps encaps;
  74         struct list_head brvccs;
  75 #ifdef CONFIG_ATM_BR2684_IPFILTER
  76         struct br2684_filter filter;
  77 #endif /* CONFIG_ATM_BR2684_IPFILTER */
  78         unsigned copies_needed, copies_failed;
  79 };
  80
  81 struct br2684_dev {
  82         struct net_device *net_dev;
  83         struct list_head br2684_devs;
  84         int number;
  85         struct list_head brvccs;        /* one device <=> one vcc (before xmas) */
  86         struct net_device_stats stats;
  87         int mac_was_set;
  88         enum br2684_payload payload;
  89 };
  90
  91 /*
  92  * This lock should be held for writing any time the list of devices or
  93  * their attached vcc's could be altered.  It should be held for reading
  94  * any time these are being queried.  Note that we sometimes need to
  95  * do read-locking under interrupt context, so write locking must block
  96  * the current CPU's interrupts
  97  */
  98 static DEFINE_RWLOCK(devs_lock);
  99
 100 static LIST_HEAD(br2684_devs);
 101
 102 static inline struct br2684_dev *BRPRIV(const struct net_device *net_dev)
 103 {
 104         return (struct br2684_dev *)net_dev->priv;
 105 }
 106
 107 static inline struct net_device *list_entry_brdev(const struct list_head *le)
 108 {
 109         return list_entry(le, struct br2684_dev, br2684_devs)->net_dev;
 110 }
 111
 112 static inline struct br2684_vcc *BR2684_VCC(const struct atm_vcc *atmvcc)
 113 {
 114         return (struct br2684_vcc *)(atmvcc->user_back);
 115 }
 116
 117 static inline struct br2684_vcc *list_entry_brvcc(const struct list_head *le)
 118 {
 119         return list_entry(le, struct br2684_vcc, brvccs);
 120 }
 121
 122 /* Caller should hold read_lock(&devs_lock) */
 123 static struct net_device *br2684_find_dev(const struct br2684_if_spec *s)
 124 {
 125         struct list_head *lh;
 126         struct net_device *net_dev;
 127         switch (s->method) {
 128         case BR2684_FIND_BYNUM:
 129                 list_for_each(lh, &br2684_devs) {
 130                         net_dev = list_entry_brdev(lh);
 131                         if (BRPRIV(net_dev)->number == s->spec.devnum)
 132                                 return net_dev;
 133                 }
 134                 break;
 135         case BR2684_FIND_BYIFNAME:
 136                 list_for_each(lh, &br2684_devs) {
 137                         net_dev = list_entry_brdev(lh);
 138                         if (!strncmp(net_dev->name, s->spec.ifname, IFNAMSIZ))
 139                                 return net_dev;
 140                 }
 141                 break;
 142         }
 143         return NULL;
 144 }
 145
 146 /*
 147  * Send a packet out a particular vcc.  Not to useful right now, but paves
 148  * the way for multiple vcc's per itf.  Returns true if we can send,
 149  * otherwise false
 150  */
 151 static int br2684_xmit_vcc(struct sk_buff *skb, struct br2684_dev *brdev,
 152                            struct br2684_vcc *brvcc)
 153 {
 154         struct atm_vcc *atmvcc;
 155         int minheadroom = (brvcc->encaps == e_llc) ? 10 : 2;
 156
 157         if (skb_headroom(skb) < minheadroom) {
 158                 struct sk_buff *skb2 = skb_realloc_headroom(skb, minheadroom);
 159                 brvcc->copies_needed++;
 160                 dev_kfree_skb(skb);
 161                 if (skb2 == NULL) {
 162                         brvcc->copies_failed++;
 163                         return 0;
 164                 }
 165                 skb = skb2;
 166         }
 167
 168         if (brvcc->encaps == e_llc) {
 169                 if (brdev->payload == p_bridged) {
 170                         skb_push(skb, sizeof(llc_oui_pid_pad));
 171                         skb_copy_to_linear_data(skb, llc_oui_pid_pad,
 172                                                 sizeof(llc_oui_pid_pad));
 173                 } else if (brdev->payload == p_routed) {
 174                         unsigned short prot = ntohs(skb->protocol);
 175
 176                         skb_push(skb, sizeof(llc_oui_ipv4));
 177                         switch (prot) {
 178                         case ETH_P_IP:
 179                                 skb_copy_to_linear_data(skb, llc_oui_ipv4,
 180                                                         sizeof(llc_oui_ipv4));
 181                                 break;
 182                         case ETH_P_IPV6:
 183                                 skb_copy_to_linear_data(skb, llc_oui_ipv6,
 184                                                         sizeof(llc_oui_ipv6));
 185                                 break;
 186                         default:
 187                                 dev_kfree_skb(skb);
 188                                 return 0;
 189                         }
 190                 }
 191         } else { /* e_vc */
 192                 if (brdev->payload == p_bridged) {
 193                         skb_push(skb, 2);
 194                         memset(skb->data, 0, 2);
 195                 } else { /* p_routed */
 196                         skb_pull(skb, ETH_HLEN);
 197                 }
 198         }
 199         skb_debug(skb);
 200
 201         ATM_SKB(skb)->vcc = atmvcc = brvcc->atmvcc;
 202         pr_debug("atm_skb(%p)->vcc(%p)->dev(%p)\n", skb, atmvcc, atmvcc->dev);
 203         if (!atm_may_send(atmvcc, skb->truesize)) {
 204                 /*
 205                  * We free this here for now, because we cannot know in a higher
 206                  * layer whether the skb pointer it supplied wasn't freed yet.
 207                  * Now, it always is.
 208                  */
 209                 dev_kfree_skb(skb);
 210                 return 0;
 211         }
 212         atomic_add(skb->truesize, &sk_atm(atmvcc)->sk_wmem_alloc);
 213         ATM_SKB(skb)->atm_options = atmvcc->atm_options;
 214         brdev->stats.tx_packets++;
 215         brdev->stats.tx_bytes += skb->len;
 216         atmvcc->send(atmvcc, skb);
 217         return 1;
 218 }
 219
 220 static inline struct br2684_vcc *pick_outgoing_vcc(const struct sk_buff *skb,
 221                                                    const struct br2684_dev *brdev)
 222 {
 223         return list_empty(&brdev->brvccs) ? NULL : list_entry_brvcc(brdev->brvccs.next);        /* 1 vcc/dev right now */
 224 }
 225
 226 static int br2684_start_xmit(struct sk_buff *skb, struct net_device *dev)
 227 {
 228         struct br2684_dev *brdev = BRPRIV(dev);
 229         struct br2684_vcc *brvcc;
 230
 231         pr_debug("br2684_start_xmit, skb->dst=%p\n", skb->dst);
 232         read_lock(&devs_lock);
 233         brvcc = pick_outgoing_vcc(skb, brdev);
 234         if (brvcc == NULL) {
 235                 pr_debug("no vcc attached to dev %s\n", dev->name);
 236                 brdev->stats.tx_errors++;
 237                 brdev->stats.tx_carrier_errors++;
 238                 /* netif_stop_queue(dev); */
 239                 dev_kfree_skb(skb);
 240                 read_unlock(&devs_lock);
 241                 return 0;
 242         }
 243         if (!br2684_xmit_vcc(skb, brdev, brvcc)) {
 244                 /*
 245                  * We should probably use netif_*_queue() here, but that
 246                  * involves added complication.  We need to walk before
 247                  * we can run.
 248                  *
 249                  * Don't free here! this pointer might be no longer valid!
 250                  */
 251                 brdev->stats.tx_errors++;
 252                 brdev->stats.tx_fifo_errors++;
 253         }
 254         read_unlock(&devs_lock);
 255         return 0;
 256 }
 257
 258 static struct net_device_stats *br2684_get_stats(struct net_device *dev)
 259 {
 260         pr_debug("br2684_get_stats\n");
 261         return &BRPRIV(dev)->stats;
 262 }
 263
 264 /*
 265  * We remember when the MAC gets set, so we don't override it later with
 266  * the ESI of the ATM card of the first VC
 267  */
 268 static int (*my_eth_mac_addr) (struct net_device *, void *);
 269 static int br2684_mac_addr(struct net_device *dev, void *p)
 270 {
 271         int err = my_eth_mac_addr(dev, p);
 272         if (!err)
 273                 BRPRIV(dev)->mac_was_set = 1;
 274         return err;
 275 }
 276
 277 #ifdef CONFIG_ATM_BR2684_IPFILTER
 278 /* this IOCTL is experimental. */
 279 static int br2684_setfilt(struct atm_vcc *atmvcc, void __user * arg)
 280 {
 281         struct br2684_vcc *brvcc;
 282         struct br2684_filter_set fs;
 283
 284         if (copy_from_user(&fs, arg, sizeof fs))
 285                 return -EFAULT;
 286         if (fs.ifspec.method != BR2684_FIND_BYNOTHING) {
 287                 /*
 288                  * This is really a per-vcc thing, but we can also search
 289                  * by device.
 290                  */
 291                 struct br2684_dev *brdev;
 292                 read_lock(&devs_lock);
 293                 brdev = BRPRIV(br2684_find_dev(&fs.ifspec));
 294                 if (brdev == NULL || list_empty(&brdev->brvccs) || brdev->brvccs.next != brdev->brvccs.prev)    /* >1 VCC */
 295                         brvcc = NULL;
 296                 else
 297                         brvcc = list_entry_brvcc(brdev->brvccs.next);
 298                 read_unlock(&devs_lock);
 299                 if (brvcc == NULL)
 300                         return -ESRCH;
 301         } else
 302                 brvcc = BR2684_VCC(atmvcc);
 303         memcpy(&brvcc->filter, &fs.filter, sizeof(brvcc->filter));
 304         return 0;
 305 }
 306
 307 /* Returns 1 if packet should be dropped */
 308 static inline int
 309 packet_fails_filter(__be16 type, struct br2684_vcc *brvcc, struct sk_buff *skb)
 310 {
 311         if (brvcc->filter.netmask == 0)
 312                 return 0;       /* no filter in place */
 313         if (type == htons(ETH_P_IP) &&
 314             (((struct iphdr *)(skb->data))->daddr & brvcc->filter.
 315              netmask) == brvcc->filter.prefix)
 316                 return 0;
 317         if (type == htons(ETH_P_ARP))
 318                 return 0;
 319         /*
 320          * TODO: we should probably filter ARPs too.. don't want to have
 321          * them returning values that don't make sense, or is that ok?
 322          */
 323         return 1;               /* drop */
 324 }
 325 #endif /* CONFIG_ATM_BR2684_IPFILTER */
 326
 327 static void br2684_close_vcc(struct br2684_vcc *brvcc)
 328 {
 329         pr_debug("removing VCC %p from dev %p\n", brvcc, brvcc->device);
 330         write_lock_irq(&devs_lock);
 331         list_del(&brvcc->brvccs);
 332         write_unlock_irq(&devs_lock);
 333         brvcc->atmvcc->user_back = NULL;        /* what about vcc->recvq ??? */
 334         brvcc->old_push(brvcc->atmvcc, NULL);   /* pass on the bad news */
 335         kfree(brvcc);
 336         module_put(THIS_MODULE);
 337 }
 338
 339 /* when AAL5 PDU comes in: */
 340 static void br2684_push(struct atm_vcc *atmvcc, struct sk_buff *skb)
 341 {
 342         struct br2684_vcc *brvcc = BR2684_VCC(atmvcc);
 343         struct net_device *net_dev = brvcc->device;
 344         struct br2684_dev *brdev = BRPRIV(net_dev);
 345
 346         pr_debug("br2684_push\n");
 347
 348         if (unlikely(skb == NULL)) {
 349                 /* skb==NULL means VCC is being destroyed */
 350                 br2684_close_vcc(brvcc);
 351                 if (list_empty(&brdev->brvccs)) {
 352                         write_lock_irq(&devs_lock);
 353                         list_del(&brdev->br2684_devs);
 354                         write_unlock_irq(&devs_lock);
 355                         unregister_netdev(net_dev);
 356                         free_netdev(net_dev);
 357                 }
 358                 return;
 359         }
 360
 361         skb_debug(skb);
 362         atm_return(atmvcc, skb->truesize);
 363         pr_debug("skb from brdev %p\n", brdev);
 364         if (brvcc->encaps == e_llc) {
 365
 366                 if (skb->len > 7 && skb->data[7] == 0x01)
 367                         __skb_trim(skb, skb->len - 4);
 368
 369                 /* accept packets that have "ipv[46]" in the snap header */
 370                 if ((skb->len >= (sizeof(llc_oui_ipv4)))
 371                     &&
 372                     (memcmp
 373                      (skb->data, llc_oui_ipv4,
 374                       sizeof(llc_oui_ipv4) - BR2684_ETHERTYPE_LEN) == 0)) {
 375                         if (memcmp
 376                             (skb->data + 6, ethertype_ipv6,
 377                              sizeof(ethertype_ipv6)) == 0)
 378                                 skb->protocol = htons(ETH_P_IPV6);
 379                         else if (memcmp
 380                                  (skb->data + 6, ethertype_ipv4,
 381                                   sizeof(ethertype_ipv4)) == 0)
 382                                 skb->protocol = htons(ETH_P_IP);
 383                         else
 384                                 goto error;
 385                         skb_pull(skb, sizeof(llc_oui_ipv4));
 386                         skb_reset_network_header(skb);
 387                         skb->pkt_type = PACKET_HOST;
 388                         /*
 389                          * Let us waste some time for checking the encapsulation.
 390                          * Note, that only 7 char is checked so frames with a valid FCS
 391                          * are also accepted (but FCS is not checked of course).
 392                          */
 393                 } else if ((skb->len >= sizeof(llc_oui_pid_pad)) &&
 394                            (memcmp(skb->data, llc_oui_pid_pad, 7) == 0)) {
 395                         skb_pull(skb, sizeof(llc_oui_pid_pad));
 396                         skb->protocol = eth_type_trans(skb, net_dev);
 397                 } else
 398                         goto error;
 399
 400         } else { /* e_vc */
 401                 if (brdev->payload == p_routed) {
 402                         struct iphdr *iph;
 403
 404                         skb_reset_network_header(skb);
 405                         iph = ip_hdr(skb);
 406                         if (iph->version == 4)
 407                                 skb->protocol = htons(ETH_P_IP);
 408                         else if (iph->version == 6)
 409                                 skb->protocol = htons(ETH_P_IPV6);
 410                         else
 411                                 goto error;
 412                         skb->pkt_type = PACKET_HOST;
 413                 } else { /* p_bridged */
 414                         /* first 2 chars should be 0 */
 415                         if (*((u16 *) (skb->data)) != 0)
 416                                 goto error;
 417                         skb_pull(skb, BR2684_PAD_LEN);
 418                         skb->protocol = eth_type_trans(skb, net_dev);
 419                 }
 420         }
 421
 422 #ifdef CONFIG_ATM_BR2684_IPFILTER
 423         if (unlikely(packet_fails_filter(skb->protocol, brvcc, skb)))
 424                 goto dropped;
 425 #endif /* CONFIG_ATM_BR2684_IPFILTER */
 426         skb->dev = net_dev;
 427         ATM_SKB(skb)->vcc = atmvcc;     /* needed ? */
 428         pr_debug("received packet's protocol: %x\n", ntohs(skb->protocol));
 429         skb_debug(skb);
 430         /* sigh, interface is down? */
 431         if (unlikely(!(net_dev->flags & IFF_UP)))
 432                 goto dropped;
 433         brdev->stats.rx_packets++;
 434         brdev->stats.rx_bytes += skb->len;
 435         memset(ATM_SKB(skb), 0, sizeof(struct atm_skb_data));
 436         netif_rx(skb);
 437         return;
 438
 439 dropped:
 440         brdev->stats.rx_dropped++;
 441         goto free_skb;
 442 error:
 443         brdev->stats.rx_errors++;
 444 free_skb:
 445         dev_kfree_skb(skb);
 446         return;
 447 }
 448
 449 /*
 450  * Assign a vcc to a dev
 451  * Note: we do not have explicit unassign, but look at _push()
 452  */
 453 static int br2684_regvcc(struct atm_vcc *atmvcc, void __user * arg)
 454 {
 455         int err;
 456         struct br2684_vcc *brvcc;
 457         struct sk_buff *skb;
 458         struct sk_buff_head *rq;
 459         struct br2684_dev *brdev;
 460         struct net_device *net_dev;
 461         struct atm_backend_br2684 be;
 462         unsigned long flags;
 463
 464         if (copy_from_user(&be, arg, sizeof be))
 465                 return -EFAULT;
 466         brvcc = kzalloc(sizeof(struct br2684_vcc), GFP_KERNEL);
 467         if (!brvcc)
 468                 return -ENOMEM;
 469         write_lock_irq(&devs_lock);
 470         net_dev = br2684_find_dev(&be.ifspec);
 471         if (net_dev == NULL) {
 472                 printk(KERN_ERR
 473                        "br2684: tried to attach to non-existant device\n");
 474                 err = -ENXIO;
 475                 goto error;
 476         }
 477         brdev = BRPRIV(net_dev);
 478         if (atmvcc->push == NULL) {
 479                 err = -EBADFD;
 480                 goto error;
 481         }
 482         if (!list_empty(&brdev->brvccs)) {
 483                 /* Only 1 VCC/dev right now */
 484                 err = -EEXIST;
 485                 goto error;
 486         }
 487         if (be.fcs_in != BR2684_FCSIN_NO || be.fcs_out != BR2684_FCSOUT_NO ||
 488             be.fcs_auto || be.has_vpiid || be.send_padding || (be.encaps !=
 489                                                                BR2684_ENCAPS_VC
 490                                                                && be.encaps !=
 491                                                                BR2684_ENCAPS_LLC)
 492             || be.min_size != 0) {
 493                 err = -EINVAL;
 494                 goto error;
 495         }
 496         pr_debug("br2684_regvcc vcc=%p, encaps=%d, brvcc=%p\n", atmvcc,
 497                  be.encaps, brvcc);
 498         if (list_empty(&brdev->brvccs) && !brdev->mac_was_set) {
 499                 unsigned char *esi = atmvcc->dev->esi;
 500                 if (esi[0] | esi[1] | esi[2] | esi[3] | esi[4] | esi[5])
 501                         memcpy(net_dev->dev_addr, esi, net_dev->addr_len);
 502                 else
 503                         net_dev->dev_addr[2] = 1;
 504         }
 505         list_add(&brvcc->brvccs, &brdev->brvccs);
 506         write_unlock_irq(&devs_lock);
 507         brvcc->device = net_dev;
 508         brvcc->atmvcc = atmvcc;
 509         atmvcc->user_back = brvcc;
 510         brvcc->encaps = (enum br2684_encaps)be.encaps;
 511         brvcc->old_push = atmvcc->push;
 512         barrier();
 513         atmvcc->push = br2684_push;
 514
 515         rq = &sk_atm(atmvcc)->sk_receive_queue;
 516
 517         spin_lock_irqsave(&rq->lock, flags);
 518         if (skb_queue_empty(rq)) {
 519                 skb = NULL;
 520         } else {
 521                 /* NULL terminate the list.  */
 522                 rq->prev->next = NULL;
 523                 skb = rq->next;
 524         }
 525         rq->prev = rq->next = (struct sk_buff *)rq;
 526         rq->qlen = 0;
 527         spin_unlock_irqrestore(&rq->lock, flags);
 528
 529         while (skb) {
 530                 struct sk_buff *next = skb->next;
 531
 532                 skb->next = skb->prev = NULL;
 533                 br2684_push(atmvcc, skb);
 534                 BRPRIV(skb->dev)->stats.rx_bytes -= skb->len;
 535                 BRPRIV(skb->dev)->stats.rx_packets--;
 536
 537                 skb = next;
 538         }
 539         __module_get(THIS_MODULE);
 540         return 0;
 541       error:
 542         write_unlock_irq(&devs_lock);
 543         kfree(brvcc);
 544         return err;
 545 }
 546
 547 static void br2684_setup(struct net_device *netdev)
 548 {
 549         struct br2684_dev *brdev = BRPRIV(netdev);
 550
 551         ether_setup(netdev);
 552         brdev->net_dev = netdev;
 553
 554         my_eth_mac_addr = netdev->set_mac_address;
 555         netdev->set_mac_address = br2684_mac_addr;
 556         netdev->hard_start_xmit = br2684_start_xmit;
 557         netdev->get_stats = br2684_get_stats;
 558
 559         INIT_LIST_HEAD(&brdev->brvccs);
 560 }
 561
 562 static void br2684_setup_routed(struct net_device *netdev)
 563 {
 564         struct br2684_dev *brdev = BRPRIV(netdev);
 565         brdev->net_dev = netdev;
 566
 567         netdev->hard_header_len = 0;
 568         my_eth_mac_addr = netdev->set_mac_address;
 569         netdev->set_mac_address = br2684_mac_addr;
 570         netdev->hard_start_xmit = br2684_start_xmit;
 571         netdev->get_stats = br2684_get_stats;
 572         netdev->addr_len = 0;
 573         netdev->mtu = 1500;
 574         netdev->type = ARPHRD_PPP;
 575         netdev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
 576         netdev->tx_queue_len = 100;
 577         INIT_LIST_HEAD(&brdev->brvccs);
 578 }
 579
 580 static int br2684_create(void __user * arg)
 581 {
 582         int err;
 583         struct net_device *netdev;
 584         struct br2684_dev *brdev;
 585         struct atm_newif_br2684 ni;
 586         enum br2684_payload payload;
 587
 588         pr_debug("br2684_create\n");
 589
 590         if (copy_from_user(&ni, arg, sizeof ni)) {
 591                 return -EFAULT;
 592         }
 593
 594         if (ni.media & BR2684_FLAG_ROUTED)
 595                 payload = p_routed;
 596         else
 597                 payload = p_bridged;
 598         ni.media &= 0xffff;     /* strip flags */
 599
 600         if (ni.media != BR2684_MEDIA_ETHERNET || ni.mtu != 1500) {
 601                 return -EINVAL;
 602         }
 603
 604         netdev = alloc_netdev(sizeof(struct br2684_dev),
 605                               ni.ifname[0] ? ni.ifname : "nas%d",
 606                               (payload == p_routed) ?
 607                               br2684_setup_routed : br2684_setup);
 608         if (!netdev)
 609                 return -ENOMEM;
 610
 611         brdev = BRPRIV(netdev);
 612
 613         pr_debug("registered netdev %s\n", netdev->name);
 614         /* open, stop, do_ioctl ? */
 615         err = register_netdev(netdev);
 616         if (err < 0) {
 617                 printk(KERN_ERR "br2684_create: register_netdev failed\n");
 618                 free_netdev(netdev);
 619                 return err;
 620         }
 621
 622         write_lock_irq(&devs_lock);
 623         brdev->payload = payload;
 624         brdev->number = list_empty(&br2684_devs) ? 1 :
 625             BRPRIV(list_entry_brdev(br2684_devs.prev))->number + 1;
 626         list_add_tail(&brdev->br2684_devs, &br2684_devs);
 627         write_unlock_irq(&devs_lock);
 628         return 0;
 629 }
 630
 631 /*
 632  * This handles ioctls actually performed on our vcc - we must return
 633  * -ENOIOCTLCMD for any unrecognized ioctl
 634  */
 635 static int br2684_ioctl(struct socket *sock, unsigned int cmd,
 636                         unsigned long arg)
 637 {
 638         struct atm_vcc *atmvcc = ATM_SD(sock);
 639         void __user *argp = (void __user *)arg;
 640         atm_backend_t b;
 641
 642         int err;
 643         switch (cmd) {
 644         case ATM_SETBACKEND:
 645         case ATM_NEWBACKENDIF:
 646                 err = get_user(b, (atm_backend_t __user *) argp);
 647                 if (err)
 648                         return -EFAULT;
 649                 if (b != ATM_BACKEND_BR2684)
 650                         return -ENOIOCTLCMD;
 651                 if (!capable(CAP_NET_ADMIN))
 652                         return -EPERM;
 653                 if (cmd == ATM_SETBACKEND)
 654                         return br2684_regvcc(atmvcc, argp);
 655                 else
 656                         return br2684_create(argp);
 657 #ifdef CONFIG_ATM_BR2684_IPFILTER
 658         case BR2684_SETFILT:
 659                 if (atmvcc->push != br2684_push)
 660                         return -ENOIOCTLCMD;
 661                 if (!capable(CAP_NET_ADMIN))
 662                         return -EPERM;
 663                 err = br2684_setfilt(atmvcc, argp);
 664
 665                 return err;
 666 #endif /* CONFIG_ATM_BR2684_IPFILTER */
 667         }
 668         return -ENOIOCTLCMD;
 669 }
 670
 671 static struct atm_ioctl br2684_ioctl_ops = {
 672         .owner = THIS_MODULE,
 673         .ioctl = br2684_ioctl,
 674 };
 675
 676 #ifdef CONFIG_PROC_FS
 677 static void *br2684_seq_start(struct seq_file *seq, loff_t * pos)
 678         __acquires(devs_lock)
 679 {
 680         read_lock(&devs_lock);
 681         return seq_list_start(&br2684_devs, *pos);
 682 }
 683
 684 static void *br2684_seq_next(struct seq_file *seq, void *v, loff_t * pos)
 685 {
 686         return seq_list_next(v, &br2684_devs, pos);
 687 }
 688
 689 static void br2684_seq_stop(struct seq_file *seq, void *v)
 690         __releases(devs_lock)
 691 {
 692         read_unlock(&devs_lock);
 693 }
 694
 695 static int br2684_seq_show(struct seq_file *seq, void *v)
 696 {
 697         const struct br2684_dev *brdev = list_entry(v, struct br2684_dev,
 698                                                     br2684_devs);
 699         const struct net_device *net_dev = brdev->net_dev;
 700         const struct br2684_vcc *brvcc;
 701         DECLARE_MAC_BUF(mac);
 702
 703         seq_printf(seq, "dev %.16s: num=%d, mac=%s (%s)\n",
 704                    net_dev->name,
 705                    brdev->number,
 706                    print_mac(mac, net_dev->dev_addr),
 707                    brdev->mac_was_set ? "set" : "auto");
 708
 709         list_for_each_entry(brvcc, &brdev->brvccs, brvccs) {
 710                 seq_printf(seq, "  vcc %d.%d.%d: encaps=%s payload=%s"
 711                            ", failed copies %u/%u"
 712                            "\n", brvcc->atmvcc->dev->number,
 713                            brvcc->atmvcc->vpi, brvcc->atmvcc->vci,
 714                            (brvcc->encaps == e_llc) ? "LLC" : "VC",
 715                            (brdev->payload == p_bridged) ? "bridged" : "routed",
 716                            brvcc->copies_failed, brvcc->copies_needed);
 717 #ifdef CONFIG_ATM_BR2684_IPFILTER
 718 #define b1(var, byte)   ((u8 *) &brvcc->filter.var)[byte]
 719 #define bs(var)         b1(var, 0), b1(var, 1), b1(var, 2), b1(var, 3)
 720                 if (brvcc->filter.netmask != 0)
 721                         seq_printf(seq, "    filter=%d.%d.%d.%d/"
 722                                    "%d.%d.%d.%d\n", bs(prefix), bs(netmask));
 723 #undef bs
 724 #undef b1
 725 #endif /* CONFIG_ATM_BR2684_IPFILTER */
 726         }
 727         return 0;
 728 }
 729
 730 static const struct seq_operations br2684_seq_ops = {
 731         .start = br2684_seq_start,
 732         .next = br2684_seq_next,
 733         .stop = br2684_seq_stop,
 734         .show = br2684_seq_show,
 735 };
 736
 737 static int br2684_proc_open(struct inode *inode, struct file *file)
 738 {
 739         return seq_open(file, &br2684_seq_ops);
 740 }
 741
 742 static const struct file_operations br2684_proc_ops = {
 743         .owner = THIS_MODULE,
 744         .open = br2684_proc_open,
 745         .read = seq_read,
 746         .llseek = seq_lseek,
 747         .release = seq_release,
 748 };
 749
 750 extern struct proc_dir_entry *atm_proc_root;    /* from proc.c */
 751 #endif /* CONFIG_PROC_FS */
 752
 753 static int __init br2684_init(void)
 754 {
 755 #ifdef CONFIG_PROC_FS
 756         struct proc_dir_entry *p;
 757         p = proc_create("br2684", 0, atm_proc_root, &br2684_proc_ops);
 758         if (p == NULL)
 759                 return -ENOMEM;
 760 #endif
 761         register_atm_ioctl(&br2684_ioctl_ops);
 762         return 0;
 763 }
 764
 765 static void __exit br2684_exit(void)
 766 {
 767         struct net_device *net_dev;
 768         struct br2684_dev *brdev;
 769         struct br2684_vcc *brvcc;
 770         deregister_atm_ioctl(&br2684_ioctl_ops);
 771
 772 #ifdef CONFIG_PROC_FS
 773         remove_proc_entry("br2684", atm_proc_root);
 774 #endif
 775
 776         while (!list_empty(&br2684_devs)) {
 777                 net_dev = list_entry_brdev(br2684_devs.next);
 778                 brdev = BRPRIV(net_dev);
 779                 while (!list_empty(&brdev->brvccs)) {
 780                         brvcc = list_entry_brvcc(brdev->brvccs.next);
 781                         br2684_close_vcc(brvcc);
 782                 }
 783
 784                 list_del(&brdev->br2684_devs);
 785                 unregister_netdev(net_dev);
 786                 free_netdev(net_dev);
 787         }
 788 }
 789
 790 module_init(br2684_init);
 791 module_exit(br2684_exit);
 792
 793 MODULE_AUTHOR("Marcell GAL");
 794 MODULE_DESCRIPTION("RFC2684 bridged protocols over ATM/AAL5");
 795 MODULE_LICENSE("GPL");