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 /* chained vcc->pop function.  Check if we should wake the netif_queue */
 143 static void br2684_pop(struct atm_vcc *vcc, struct sk_buff *skb)
 144 {
 145         struct br2684_vcc *brvcc = BR2684_VCC(vcc);
 146         struct net_device *net_dev = skb->dev;
 147
 148         pr_debug("(vcc %p ; net_dev %p )\n", vcc, net_dev);
 149         brvcc->old_pop(vcc, skb);
 150
 151         if (!net_dev)
 152                 return;
 153
 154         if (atm_may_send(vcc, 0))
 155                 netif_wake_queue(net_dev);
 156
 157 }
 158 /*
 159  * Send a packet out a particular vcc.  Not to useful right now, but paves
 160  * the way for multiple vcc's per itf.  Returns true if we can send,
 161  * otherwise false
 162  */
 163 static int br2684_xmit_vcc(struct sk_buff *skb, struct net_device *dev,
 164                            struct br2684_vcc *brvcc)
 165 {
 166         struct br2684_dev *brdev = BRPRIV(dev);
 167         struct atm_vcc *atmvcc;
 168         int minheadroom = (brvcc->encaps == e_llc) ? 10 : 2;
 169
 170         if (skb_headroom(skb) < minheadroom) {
 171                 struct sk_buff *skb2 = skb_realloc_headroom(skb, minheadroom);
 172                 brvcc->copies_needed++;
 173                 dev_kfree_skb(skb);
 174                 if (skb2 == NULL) {
 175                         brvcc->copies_failed++;
 176                         return 0;
 177                 }
 178                 skb = skb2;
 179         }
 180
 181         if (brvcc->encaps == e_llc) {
 182                 if (brdev->payload == p_bridged) {
 183                         skb_push(skb, sizeof(llc_oui_pid_pad));
 184                         skb_copy_to_linear_data(skb, llc_oui_pid_pad,
 185                                                 sizeof(llc_oui_pid_pad));
 186                 } else if (brdev->payload == p_routed) {
 187                         unsigned short prot = ntohs(skb->protocol);
 188
 189                         skb_push(skb, sizeof(llc_oui_ipv4));
 190                         switch (prot) {
 191                         case ETH_P_IP:
 192                                 skb_copy_to_linear_data(skb, llc_oui_ipv4,
 193                                                         sizeof(llc_oui_ipv4));
 194                                 break;
 195                         case ETH_P_IPV6:
 196                                 skb_copy_to_linear_data(skb, llc_oui_ipv6,
 197                                                         sizeof(llc_oui_ipv6));
 198                                 break;
 199                         default:
 200                                 dev_kfree_skb(skb);
 201                                 return 0;
 202                         }
 203                 }
 204         } else { /* e_vc */
 205                 if (brdev->payload == p_bridged) {
 206                         skb_push(skb, 2);
 207                         memset(skb->data, 0, 2);
 208                 } else { /* p_routed */
 209                         skb_pull(skb, ETH_HLEN);
 210                 }
 211         }
 212         skb_debug(skb);
 213
 214         ATM_SKB(skb)->vcc = atmvcc = brvcc->atmvcc;
 215         pr_debug("atm_skb(%p)->vcc(%p)->dev(%p)\n", skb, atmvcc, atmvcc->dev);
 216         atomic_add(skb->truesize, &sk_atm(atmvcc)->sk_wmem_alloc);
 217         ATM_SKB(skb)->atm_options = atmvcc->atm_options;
 218         dev->stats.tx_packets++;
 219         dev->stats.tx_bytes += skb->len;
 220         atmvcc->send(atmvcc, skb);
 221
 222         if (!atm_may_send(atmvcc, 0)) {
 223                 netif_stop_queue(brvcc->device);
 224                 /*check for race with br2684_pop*/
 225                 if (atm_may_send(atmvcc, 0))
 226                         netif_start_queue(brvcc->device);
 227         }
 228
 229         return 1;
 230 }
 231
 232 static inline struct br2684_vcc *pick_outgoing_vcc(const struct sk_buff *skb,
 233                                                    const struct br2684_dev *brdev)
 234 {
 235         return list_empty(&brdev->brvccs) ? NULL : list_entry_brvcc(brdev->brvccs.next);        /* 1 vcc/dev right now */
 236 }
 237
 238 static netdev_tx_t br2684_start_xmit(struct sk_buff *skb,
 239                                      struct net_device *dev)
 240 {
 241         struct br2684_dev *brdev = BRPRIV(dev);
 242         struct br2684_vcc *brvcc;
 243
 244         pr_debug("skb_dst(skb)=%p\n", skb_dst(skb));
 245         read_lock(&devs_lock);
 246         brvcc = pick_outgoing_vcc(skb, brdev);
 247         if (brvcc == NULL) {
 248                 pr_debug("no vcc attached to dev %s\n", dev->name);
 249                 dev->stats.tx_errors++;
 250                 dev->stats.tx_carrier_errors++;
 251                 /* netif_stop_queue(dev); */
 252                 dev_kfree_skb(skb);
 253                 read_unlock(&devs_lock);
 254                 return NETDEV_TX_OK;
 255         }
 256         if (!br2684_xmit_vcc(skb, dev, brvcc)) {
 257                 /*
 258                  * We should probably use netif_*_queue() here, but that
 259                  * involves added complication.  We need to walk before
 260                  * we can run.
 261                  *
 262                  * Don't free here! this pointer might be no longer valid!
 263                  */
 264                 dev->stats.tx_errors++;
 265                 dev->stats.tx_fifo_errors++;
 266         }
 267         read_unlock(&devs_lock);
 268         return NETDEV_TX_OK;
 269 }
 270
 271 /*
 272  * We remember when the MAC gets set, so we don't override it later with
 273  * the ESI of the ATM card of the first VC
 274  */
 275 static int br2684_mac_addr(struct net_device *dev, void *p)
 276 {
 277         int err = eth_mac_addr(dev, p);
 278         if (!err)
 279                 BRPRIV(dev)->mac_was_set = 1;
 280         return err;
 281 }
 282
 283 #ifdef CONFIG_ATM_BR2684_IPFILTER
 284 /* this IOCTL is experimental. */
 285 static int br2684_setfilt(struct atm_vcc *atmvcc, void __user * arg)
 286 {
 287         struct br2684_vcc *brvcc;
 288         struct br2684_filter_set fs;
 289
 290         if (copy_from_user(&fs, arg, sizeof fs))
 291                 return -EFAULT;
 292         if (fs.ifspec.method != BR2684_FIND_BYNOTHING) {
 293                 /*
 294                  * This is really a per-vcc thing, but we can also search
 295                  * by device.
 296                  */
 297                 struct br2684_dev *brdev;
 298                 read_lock(&devs_lock);
 299                 brdev = BRPRIV(br2684_find_dev(&fs.ifspec));
 300                 if (brdev == NULL || list_empty(&brdev->brvccs) ||
 301                     brdev->brvccs.next != brdev->brvccs.prev)   /* >1 VCC */
 302                         brvcc = NULL;
 303                 else
 304                         brvcc = list_entry_brvcc(brdev->brvccs.next);
 305                 read_unlock(&devs_lock);
 306                 if (brvcc == NULL)
 307                         return -ESRCH;
 308         } else
 309                 brvcc = BR2684_VCC(atmvcc);
 310         memcpy(&brvcc->filter, &fs.filter, sizeof(brvcc->filter));
 311         return 0;
 312 }
 313
 314 /* Returns 1 if packet should be dropped */
 315 static inline int
 316 packet_fails_filter(__be16 type, struct br2684_vcc *brvcc, struct sk_buff *skb)
 317 {
 318         if (brvcc->filter.netmask == 0)
 319                 return 0;       /* no filter in place */
 320         if (type == htons(ETH_P_IP) &&
 321             (((struct iphdr *)(skb->data))->daddr & brvcc->filter.
 322              netmask) == brvcc->filter.prefix)
 323                 return 0;
 324         if (type == htons(ETH_P_ARP))
 325                 return 0;
 326         /*
 327          * TODO: we should probably filter ARPs too.. don't want to have
 328          * them returning values that don't make sense, or is that ok?
 329          */
 330         return 1;               /* drop */
 331 }
 332 #endif /* CONFIG_ATM_BR2684_IPFILTER */
 333
 334 static void br2684_close_vcc(struct br2684_vcc *brvcc)
 335 {
 336         pr_debug("removing VCC %p from dev %p\n", brvcc, brvcc->device);
 337         write_lock_irq(&devs_lock);
 338         list_del(&brvcc->brvccs);
 339         write_unlock_irq(&devs_lock);
 340         brvcc->atmvcc->user_back = NULL;        /* what about vcc->recvq ??? */
 341         brvcc->old_push(brvcc->atmvcc, NULL);   /* pass on the bad news */
 342         kfree(brvcc);
 343         module_put(THIS_MODULE);
 344 }
 345
 346 /* when AAL5 PDU comes in: */
 347 static void br2684_push(struct atm_vcc *atmvcc, struct sk_buff *skb)
 348 {
 349         struct br2684_vcc *brvcc = BR2684_VCC(atmvcc);
 350         struct net_device *net_dev = brvcc->device;
 351         struct br2684_dev *brdev = BRPRIV(net_dev);
 352
 353         pr_debug("\n");
 354
 355         if (unlikely(skb == NULL)) {
 356                 /* skb==NULL means VCC is being destroyed */
 357                 br2684_close_vcc(brvcc);
 358                 if (list_empty(&brdev->brvccs)) {
 359                         write_lock_irq(&devs_lock);
 360                         list_del(&brdev->br2684_devs);
 361                         write_unlock_irq(&devs_lock);
 362                         unregister_netdev(net_dev);
 363                         free_netdev(net_dev);
 364                 }
 365                 return;
 366         }
 367
 368         skb_debug(skb);
 369         atm_return(atmvcc, skb->truesize);
 370         pr_debug("skb from brdev %p\n", brdev);
 371         if (brvcc->encaps == e_llc) {
 372
 373                 if (skb->len > 7 && skb->data[7] == 0x01)
 374                         __skb_trim(skb, skb->len - 4);
 375
 376                 /* accept packets that have "ipv[46]" in the snap header */
 377                 if ((skb->len >= (sizeof(llc_oui_ipv4))) &&
 378                     (memcmp(skb->data, llc_oui_ipv4,
 379                             sizeof(llc_oui_ipv4) - BR2684_ETHERTYPE_LEN) == 0)) {
 380                         if (memcmp(skb->data + 6, ethertype_ipv6,
 381                                    sizeof(ethertype_ipv6)) == 0)
 382                                 skb->protocol = htons(ETH_P_IPV6);
 383                         else if (memcmp(skb->data + 6, ethertype_ipv4,
 384                                         sizeof(ethertype_ipv4)) == 0)
 385                                 skb->protocol = htons(ETH_P_IP);
 386                         else
 387                                 goto error;
 388                         skb_pull(skb, sizeof(llc_oui_ipv4));
 389                         skb_reset_network_header(skb);
 390                         skb->pkt_type = PACKET_HOST;
 391                 /*
 392                  * Let us waste some time for checking the encapsulation.
 393                  * Note, that only 7 char is checked so frames with a valid FCS
 394                  * are also accepted (but FCS is not checked of course).
 395                  */
 396                 } else if ((skb->len >= sizeof(llc_oui_pid_pad)) &&
 397                            (memcmp(skb->data, llc_oui_pid_pad, 7) == 0)) {
 398                         skb_pull(skb, sizeof(llc_oui_pid_pad));
 399                         skb->protocol = eth_type_trans(skb, net_dev);
 400                 } else
 401                         goto error;
 402
 403         } else { /* e_vc */
 404                 if (brdev->payload == p_routed) {
 405                         struct iphdr *iph;
 406
 407                         skb_reset_network_header(skb);
 408                         iph = ip_hdr(skb);
 409                         if (iph->version == 4)
 410                                 skb->protocol = htons(ETH_P_IP);
 411                         else if (iph->version == 6)
 412                                 skb->protocol = htons(ETH_P_IPV6);
 413                         else
 414                                 goto error;
 415                         skb->pkt_type = PACKET_HOST;
 416                 } else { /* p_bridged */
 417                         /* first 2 chars should be 0 */
 418                         if (*((u16 *) (skb->data)) != 0)
 419                                 goto error;
 420                         skb_pull(skb, BR2684_PAD_LEN);
 421                         skb->protocol = eth_type_trans(skb, net_dev);
 422                 }
 423         }
 424
 425 #ifdef CONFIG_ATM_BR2684_IPFILTER
 426         if (unlikely(packet_fails_filter(skb->protocol, brvcc, skb)))
 427                 goto dropped;
 428 #endif /* CONFIG_ATM_BR2684_IPFILTER */
 429         skb->dev = net_dev;
 430         ATM_SKB(skb)->vcc = atmvcc;     /* needed ? */
 431         pr_debug("received packet's protocol: %x\n", ntohs(skb->protocol));
 432         skb_debug(skb);
 433         /* sigh, interface is down? */
 434         if (unlikely(!(net_dev->flags & IFF_UP)))
 435                 goto dropped;
 436         net_dev->stats.rx_packets++;
 437         net_dev->stats.rx_bytes += skb->len;
 438         memset(ATM_SKB(skb), 0, sizeof(struct atm_skb_data));
 439         netif_rx(skb);
 440         return;
 441
 442 dropped:
 443         net_dev->stats.rx_dropped++;
 444         goto free_skb;
 445 error:
 446         net_dev->stats.rx_errors++;
 447 free_skb:
 448         dev_kfree_skb(skb);
 449         return;
 450 }
 451
 452 /*
 453  * Assign a vcc to a dev
 454  * Note: we do not have explicit unassign, but look at _push()
 455  */
 456 static int br2684_regvcc(struct atm_vcc *atmvcc, void __user * arg)
 457 {
 458         struct sk_buff_head queue;
 459         int err;
 460         struct br2684_vcc *brvcc;
 461         struct sk_buff *skb, *tmp;
 462         struct sk_buff_head *rq;
 463         struct br2684_dev *brdev;
 464         struct net_device *net_dev;
 465         struct atm_backend_br2684 be;
 466         unsigned long flags;
 467
 468         if (copy_from_user(&be, arg, sizeof be))
 469                 return -EFAULT;
 470         brvcc = kzalloc(sizeof(struct br2684_vcc), GFP_KERNEL);
 471         if (!brvcc)
 472                 return -ENOMEM;
 473         write_lock_irq(&devs_lock);
 474         net_dev = br2684_find_dev(&be.ifspec);
 475         if (net_dev == NULL) {
 476                 pr_err("tried to attach to non-existant device\n");
 477                 err = -ENXIO;
 478                 goto error;
 479         }
 480         brdev = BRPRIV(net_dev);
 481         if (atmvcc->push == NULL) {
 482                 err = -EBADFD;
 483                 goto error;
 484         }
 485         if (!list_empty(&brdev->brvccs)) {
 486                 /* Only 1 VCC/dev right now */
 487                 err = -EEXIST;
 488                 goto error;
 489         }
 490         if (be.fcs_in != BR2684_FCSIN_NO ||
 491             be.fcs_out != BR2684_FCSOUT_NO ||
 492             be.fcs_auto || be.has_vpiid || be.send_padding ||
 493             (be.encaps != BR2684_ENCAPS_VC &&
 494              be.encaps != BR2684_ENCAPS_LLC) ||
 495             be.min_size != 0) {
 496                 err = -EINVAL;
 497                 goto error;
 498         }
 499         pr_debug("vcc=%p, encaps=%d, brvcc=%p\n", atmvcc, be.encaps, brvcc);
 500         if (list_empty(&brdev->brvccs) && !brdev->mac_was_set) {
 501                 unsigned char *esi = atmvcc->dev->esi;
 502                 if (esi[0] | esi[1] | esi[2] | esi[3] | esi[4] | esi[5])
 503                         memcpy(net_dev->dev_addr, esi, net_dev->addr_len);
 504                 else
 505                         net_dev->dev_addr[2] = 1;
 506         }
 507         list_add(&brvcc->brvccs, &brdev->brvccs);
 508         write_unlock_irq(&devs_lock);
 509         brvcc->device = net_dev;
 510         brvcc->atmvcc = atmvcc;
 511         atmvcc->user_back = brvcc;
 512         brvcc->encaps = (enum br2684_encaps)be.encaps;
 513         brvcc->old_push = atmvcc->push;
 514         brvcc->old_pop = atmvcc->pop;
 515         barrier();
 516         atmvcc->push = br2684_push;
 517         atmvcc->pop = br2684_pop;
 518
 519         __skb_queue_head_init(&queue);
 520         rq = &sk_atm(atmvcc)->sk_receive_queue;
 521
 522         spin_lock_irqsave(&rq->lock, flags);
 523         skb_queue_splice_init(rq, &queue);
 524         spin_unlock_irqrestore(&rq->lock, flags);
 525
 526         skb_queue_walk_safe(&queue, skb, tmp) {
 527                 struct net_device *dev = skb->dev;
 528
 529                 dev->stats.rx_bytes -= skb->len;
 530                 dev->stats.rx_packets--;
 531
 532                 br2684_push(atmvcc, skb);
 533         }
 534         __module_get(THIS_MODULE);
 535         return 0;
 536
 537 error:
 538         write_unlock_irq(&devs_lock);
 539         kfree(brvcc);
 540         return err;
 541 }
 542
 543 static const struct net_device_ops br2684_netdev_ops = {
 544         .ndo_start_xmit         = br2684_start_xmit,
 545         .ndo_set_mac_address    = br2684_mac_addr,
 546         .ndo_change_mtu         = eth_change_mtu,
 547         .ndo_validate_addr      = eth_validate_addr,
 548 };
 549
 550 static const struct net_device_ops br2684_netdev_ops_routed = {
 551         .ndo_start_xmit         = br2684_start_xmit,
 552         .ndo_set_mac_address    = br2684_mac_addr,
 553         .ndo_change_mtu         = eth_change_mtu
 554 };
 555
 556 static void br2684_setup(struct net_device *netdev)
 557 {
 558         struct br2684_dev *brdev = BRPRIV(netdev);
 559
 560         ether_setup(netdev);
 561         brdev->net_dev = netdev;
 562
 563         netdev->netdev_ops = &br2684_netdev_ops;
 564
 565         INIT_LIST_HEAD(&brdev->brvccs);
 566 }
 567
 568 static void br2684_setup_routed(struct net_device *netdev)
 569 {
 570         struct br2684_dev *brdev = BRPRIV(netdev);
 571
 572         brdev->net_dev = netdev;
 573         netdev->hard_header_len = 0;
 574         netdev->netdev_ops = &br2684_netdev_ops_routed;
 575         netdev->addr_len = 0;
 576         netdev->mtu = 1500;
 577         netdev->type = ARPHRD_PPP;
 578         netdev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
 579         netdev->tx_queue_len = 100;
 580         INIT_LIST_HEAD(&brdev->brvccs);
 581 }
 582
 583 static int br2684_create(void __user *arg)
 584 {
 585         int err;
 586         struct net_device *netdev;
 587         struct br2684_dev *brdev;
 588         struct atm_newif_br2684 ni;
 589         enum br2684_payload payload;
 590
 591         pr_debug("\n");
 592
 593         if (copy_from_user(&ni, arg, sizeof ni))
 594                 return -EFAULT;
 595
 596         if (ni.media & BR2684_FLAG_ROUTED)
 597                 payload = p_routed;
 598         else
 599                 payload = p_bridged;
 600         ni.media &= 0xffff;     /* strip flags */
 601
 602         if (ni.media != BR2684_MEDIA_ETHERNET || ni.mtu != 1500)
 603                 return -EINVAL;
 604
 605         netdev = alloc_netdev(sizeof(struct br2684_dev),
 606                               ni.ifname[0] ? ni.ifname : "nas%d",
 607                               (payload == p_routed) ?
 608                               br2684_setup_routed : br2684_setup);
 609         if (!netdev)
 610                 return -ENOMEM;
 611
 612         brdev = BRPRIV(netdev);
 613
 614         pr_debug("registered netdev %s\n", netdev->name);
 615         /* open, stop, do_ioctl ? */
 616         err = register_netdev(netdev);
 617         if (err < 0) {
 618                 pr_err("register_netdev failed\n");
 619                 free_netdev(netdev);
 620                 return err;
 621         }
 622
 623         write_lock_irq(&devs_lock);
 624         brdev->payload = payload;
 625         brdev->number = list_empty(&br2684_devs) ? 1 :
 626             BRPRIV(list_entry_brdev(br2684_devs.prev))->number + 1;
 627         list_add_tail(&brdev->br2684_devs, &br2684_devs);
 628         write_unlock_irq(&devs_lock);
 629         return 0;
 630 }
 631
 632 /*
 633  * This handles ioctls actually performed on our vcc - we must return
 634  * -ENOIOCTLCMD for any unrecognized ioctl
 635  */
 636 static int br2684_ioctl(struct socket *sock, unsigned int cmd,
 637                         unsigned long arg)
 638 {
 639         struct atm_vcc *atmvcc = ATM_SD(sock);
 640         void __user *argp = (void __user *)arg;
 641         atm_backend_t b;
 642
 643         int err;
 644         switch (cmd) {
 645         case ATM_SETBACKEND:
 646         case ATM_NEWBACKENDIF:
 647                 err = get_user(b, (atm_backend_t __user *) argp);
 648                 if (err)
 649                         return -EFAULT;
 650                 if (b != ATM_BACKEND_BR2684)
 651                         return -ENOIOCTLCMD;
 652                 if (!capable(CAP_NET_ADMIN))
 653                         return -EPERM;
 654                 if (cmd == ATM_SETBACKEND)
 655                         return br2684_regvcc(atmvcc, argp);
 656                 else
 657                         return br2684_create(argp);
 658 #ifdef CONFIG_ATM_BR2684_IPFILTER
 659         case BR2684_SETFILT:
 660                 if (atmvcc->push != br2684_push)
 661                         return -ENOIOCTLCMD;
 662                 if (!capable(CAP_NET_ADMIN))
 663                         return -EPERM;
 664                 err = br2684_setfilt(atmvcc, argp);
 665
 666                 return err;
 667 #endif /* CONFIG_ATM_BR2684_IPFILTER */
 668         }
 669         return -ENOIOCTLCMD;
 670 }
 671
 672 static struct atm_ioctl br2684_ioctl_ops = {
 673         .owner = THIS_MODULE,
 674         .ioctl = br2684_ioctl,
 675 };
 676
 677 #ifdef CONFIG_PROC_FS
 678 static void *br2684_seq_start(struct seq_file *seq, loff_t * pos)
 679         __acquires(devs_lock)
 680 {
 681         read_lock(&devs_lock);
 682         return seq_list_start(&br2684_devs, *pos);
 683 }
 684
 685 static void *br2684_seq_next(struct seq_file *seq, void *v, loff_t * pos)
 686 {
 687         return seq_list_next(v, &br2684_devs, pos);
 688 }
 689
 690 static void br2684_seq_stop(struct seq_file *seq, void *v)
 691         __releases(devs_lock)
 692 {
 693         read_unlock(&devs_lock);
 694 }
 695
 696 static int br2684_seq_show(struct seq_file *seq, void *v)
 697 {
 698         const struct br2684_dev *brdev = list_entry(v, struct br2684_dev,
 699                                                     br2684_devs);
 700         const struct net_device *net_dev = brdev->net_dev;
 701         const struct br2684_vcc *brvcc;
 702
 703         seq_printf(seq, "dev %.16s: num=%d, mac=%pM (%s)\n",
 704                    net_dev->name,
 705                    brdev->number,
 706                    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");