net/wanrouter/wanmain.c

   1 /*****************************************************************************
   2 * wanmain.c     WAN Multiprotocol Router Module. Main code.
   3 *
   4 *               This module is completely hardware-independent and provides
   5 *               the following common services for the WAN Link Drivers:
   6 *                o WAN device management (registering, unregistering)
   7 *                o Network interface management
   8 *                o Physical connection management (dial-up, incoming calls)
   9 *                o Logical connection management (switched virtual circuits)
  10 *                o Protocol encapsulation/decapsulation
  11 *
  12 * Author:       Gideon Hack
  13 *
  14 * Copyright:    (c) 1995-1999 Sangoma Technologies Inc.
  15 *
  16 *               This program is free software; you can redistribute it and/or
  17 *               modify it under the terms of the GNU General Public License
  18 *               as published by the Free Software Foundation; either version
  19 *               2 of the License, or (at your option) any later version.
  20 * ============================================================================
  21 * Nov 24, 2000  Nenad Corbic    Updated for 2.4.X kernels
  22 * Nov 07, 2000  Nenad Corbic    Fixed the Mulit-Port PPP for kernels 2.2.16 and
  23 *                               greater.
  24 * Aug 2,  2000  Nenad Corbic    Block the Multi-Port PPP from running on
  25 *                               kernels 2.2.16 or greater.  The SyncPPP
  26 *                               has changed.
  27 * Jul 13, 2000  Nenad Corbic    Added SyncPPP support
  28 *                               Added extra debugging in device_setup().
  29 * Oct 01, 1999  Gideon Hack     Update for s514 PCI card
  30 * Dec 27, 1996  Gene Kozin      Initial version (based on Sangoma's WANPIPE)
  31 * Jan 16, 1997  Gene Kozin      router_devlist made public
  32 * Jan 31, 1997  Alan Cox        Hacked it about a bit for 2.1
  33 * Jun 27, 1997  Alan Cox        realigned with vendor code
  34 * Oct 15, 1997  Farhan Thawar   changed wan_encapsulate to add a pad byte of 0
  35 * Apr 20, 1998  Alan Cox        Fixed 2.1 symbols
  36 * May 17, 1998  K. Baranowski   Fixed SNAP encapsulation in wan_encapsulate
  37 * Dec 15, 1998  Arnaldo Melo    support for firmwares of up to 128000 bytes
  38 *                               check wandev->setup return value
  39 * Dec 22, 1998  Arnaldo Melo    vmalloc/vfree used in device_setup to allocate
  40 *                               kernel memory and copy configuration data to
  41 *                               kernel space (for big firmwares)
  42 * Jun 02, 1999  Gideon Hack     Updates for Linux 2.0.X and 2.2.X kernels.
  43 *****************************************************************************/
  44
  45 #include <linux/stddef.h>       /* offsetof(), etc. */
  46 #include <linux/capability.h>
  47 #include <linux/errno.h>        /* return codes */
  48 #include <linux/kernel.h>
  49 #include <linux/init.h>
  50 #include <linux/module.h>       /* support for loadable modules */
  51 #include <linux/slab.h>         /* kmalloc(), kfree() */
  52 #include <linux/mm.h>
  53 #include <linux/string.h>       /* inline mem*, str* functions */
  54
  55 #include <asm/byteorder.h>      /* htons(), etc. */
  56 #include <linux/wanrouter.h>    /* WAN router API definitions */
  57
  58 #include <linux/vmalloc.h>      /* vmalloc, vfree */
  59 #include <asm/uaccess.h>        /* copy_to/from_user */
  60 #include <linux/init.h>         /* __initfunc et al. */
  61 #include <net/syncppp.h>
  62
  63 #define KMEM_SAFETYZONE 8
  64
  65 /*
  66  *      Function Prototypes
  67  */
  68
  69 /*
  70  *      WAN device IOCTL handlers
  71  */
  72
  73 static int wanrouter_device_setup(struct wan_device *wandev,
  74                                   wandev_conf_t __user *u_conf);
  75 static int wanrouter_device_stat(struct wan_device *wandev,
  76                                  wandev_stat_t __user *u_stat);
  77 static int wanrouter_device_shutdown(struct wan_device *wandev);
  78 static int wanrouter_device_new_if(struct wan_device *wandev,
  79                                    wanif_conf_t __user *u_conf);
  80 static int wanrouter_device_del_if(struct wan_device *wandev,
  81                                    char __user *u_name);
  82
  83 /*
  84  *      Miscellaneous
  85  */
  86
  87 static struct wan_device *wanrouter_find_device(char *name);
  88 static int wanrouter_delete_interface(struct wan_device *wandev, char *name);
  89 static void lock_adapter_irq(spinlock_t *lock, unsigned long *smp_flags);
  90 static void unlock_adapter_irq(spinlock_t *lock, unsigned long *smp_flags);
  91
  92
  93
  94 /*
  95  *      Global Data
  96  */
  97
  98 static char wanrouter_fullname[]  = "Sangoma WANPIPE Router";
  99 static char wanrouter_copyright[] = "(c) 1995-2000 Sangoma Technologies Inc.";
 100 static char wanrouter_modname[] = ROUTER_NAME; /* short module name */
 101 struct wan_device* wanrouter_router_devlist; /* list of registered devices */
 102
 103 /*
 104  *      Organize Unique Identifiers for encapsulation/decapsulation
 105  */
 106
 107 #if 0
 108 static unsigned char wanrouter_oui_ether[] = { 0x00, 0x00, 0x00 };
 109 static unsigned char wanrouter_oui_802_2[] = { 0x00, 0x80, 0xC2 };
 110 #endif
 111
 112 static int __init wanrouter_init(void)
 113 {
 114         int err;
 115
 116         printk(KERN_INFO "%s v%u.%u %s\n",
 117                wanrouter_fullname, ROUTER_VERSION, ROUTER_RELEASE,
 118                wanrouter_copyright);
 119
 120         err = wanrouter_proc_init();
 121         if (err)
 122                 printk(KERN_INFO "%s: can't create entry in proc filesystem!\n",
 123                        wanrouter_modname);
 124
 125         return err;
 126 }
 127
 128 static void __exit wanrouter_cleanup (void)
 129 {
 130         wanrouter_proc_cleanup();
 131 }
 132
 133 /*
 134  * This is just plain dumb.  We should move the bugger to drivers/net/wan,
 135  * slap it first in directory and make it module_init().  The only reason
 136  * for subsys_initcall() here is that net goes after drivers (why, BTW?)
 137  */
 138 subsys_initcall(wanrouter_init);
 139 module_exit(wanrouter_cleanup);
 140
 141 /*
 142  *      Kernel APIs
 143  */
 144
 145 /*
 146  *      Register WAN device.
 147  *      o verify device credentials
 148  *      o create an entry for the device in the /proc/net/router directory
 149  *      o initialize internally maintained fields of the wan_device structure
 150  *      o link device data space to a singly-linked list
 151  *      o if it's the first device, then start kernel 'thread'
 152  *      o increment module use count
 153  *
 154  *      Return:
 155  *      0       Ok
 156  *      < 0     error.
 157  *
 158  *      Context:        process
 159  */
 160
 161
 162 int register_wan_device(struct wan_device *wandev)
 163 {
 164         int err, namelen;
 165
 166         if ((wandev == NULL) || (wandev->magic != ROUTER_MAGIC) ||
 167             (wandev->name == NULL))
 168                 return -EINVAL;
 169
 170         namelen = strlen(wandev->name);
 171         if (!namelen || (namelen > WAN_DRVNAME_SZ))
 172                 return -EINVAL;
 173
 174         if (wanrouter_find_device(wandev->name))
 175                 return -EEXIST;
 176
 177 #ifdef WANDEBUG
 178         printk(KERN_INFO "%s: registering WAN device %s\n",
 179                wanrouter_modname, wandev->name);
 180 #endif
 181
 182         /*
 183          *      Register /proc directory entry
 184          */
 185         err = wanrouter_proc_add(wandev);
 186         if (err) {
 187                 printk(KERN_INFO
 188                         "%s: can't create /proc/net/router/%s entry!\n",
 189                         wanrouter_modname, wandev->name);
 190                 return err;
 191         }
 192
 193         /*
 194          *      Initialize fields of the wan_device structure maintained by the
 195          *      router and update local data.
 196          */
 197
 198         wandev->ndev = 0;
 199         wandev->dev  = NULL;
 200         wandev->next = wanrouter_router_devlist;
 201         wanrouter_router_devlist = wandev;
 202         return 0;
 203 }
 204
 205 /*
 206  *      Unregister WAN device.
 207  *      o shut down device
 208  *      o unlink device data space from the linked list
 209  *      o delete device entry in the /proc/net/router directory
 210  *      o decrement module use count
 211  *
 212  *      Return:         0       Ok
 213  *                      <0      error.
 214  *      Context:        process
 215  */
 216
 217
 218 int unregister_wan_device(char *name)
 219 {
 220         struct wan_device *wandev, *prev;
 221
 222         if (name == NULL)
 223                 return -EINVAL;
 224
 225         for (wandev = wanrouter_router_devlist, prev = NULL;
 226                 wandev && strcmp(wandev->name, name);
 227                 prev = wandev, wandev = wandev->next)
 228                 ;
 229         if (wandev == NULL)
 230                 return -ENODEV;
 231
 232 #ifdef WANDEBUG
 233         printk(KERN_INFO "%s: unregistering WAN device %s\n",
 234                wanrouter_modname, name);
 235 #endif
 236
 237         if (wandev->state != WAN_UNCONFIGURED)
 238                 wanrouter_device_shutdown(wandev);
 239
 240         if (prev)
 241                 prev->next = wandev->next;
 242         else
 243                 wanrouter_router_devlist = wandev->next;
 244
 245         wanrouter_proc_delete(wandev);
 246         return 0;
 247 }
 248
 249 #if 0
 250
 251 /*
 252  *      Encapsulate packet.
 253  *
 254  *      Return: encapsulation header size
 255  *              < 0     - unsupported Ethertype
 256  *
 257  *      Notes:
 258  *      1. This function may be called on interrupt context.
 259  */
 260
 261
 262 int wanrouter_encapsulate(struct sk_buff *skb, struct net_device *dev,
 263                           unsigned short type)
 264 {
 265         int hdr_len = 0;
 266
 267         switch (type) {
 268         case ETH_P_IP:          /* IP datagram encapsulation */
 269                 hdr_len += 1;
 270                 skb_push(skb, 1);
 271                 skb->data[0] = NLPID_IP;
 272                 break;
 273
 274         case ETH_P_IPX:         /* SNAP encapsulation */
 275         case ETH_P_ARP:
 276                 hdr_len += 7;
 277                 skb_push(skb, 7);
 278                 skb->data[0] = 0;
 279                 skb->data[1] = NLPID_SNAP;
 280                 memcpy(&skb->data[2], wanrouter_oui_ether,
 281                        sizeof(wanrouter_oui_ether));
 282                 *((unsigned short*)&skb->data[5]) = htons(type);
 283                 break;
 284
 285         default:                /* Unknown packet type */
 286                 printk(KERN_INFO
 287                         "%s: unsupported Ethertype 0x%04X on interface %s!\n",
 288                         wanrouter_modname, type, dev->name);
 289                 hdr_len = -EINVAL;
 290         }
 291         return hdr_len;
 292 }
 293
 294
 295 /*
 296  *      Decapsulate packet.
 297  *
 298  *      Return: Ethertype (in network order)
 299  *                      0       unknown encapsulation
 300  *
 301  *      Notes:
 302  *      1. This function may be called on interrupt context.
 303  */
 304
 305
 306 __be16 wanrouter_type_trans(struct sk_buff *skb, struct net_device *dev)
 307 {
 308         int cnt = skb->data[0] ? 0 : 1; /* there may be a pad present */
 309         __be16 ethertype;
 310
 311         switch (skb->data[cnt]) {
 312         case NLPID_IP:          /* IP datagramm */
 313                 ethertype = htons(ETH_P_IP);
 314                 cnt += 1;
 315                 break;
 316
 317         case NLPID_SNAP:        /* SNAP encapsulation */
 318                 if (memcmp(&skb->data[cnt + 1], wanrouter_oui_ether,
 319                            sizeof(wanrouter_oui_ether))){
 320                         printk(KERN_INFO
 321                                 "%s: unsupported SNAP OUI %02X-%02X-%02X "
 322                                 "on interface %s!\n", wanrouter_modname,
 323                                 skb->data[cnt+1], skb->data[cnt+2],
 324                                 skb->data[cnt+3], dev->name);
 325                         return 0;
 326                 }
 327                 ethertype = *((__be16*)&skb->data[cnt+4]);
 328                 cnt += 6;
 329                 break;
 330
 331         /* add other protocols, e.g. CLNP, ESIS, ISIS, if needed */
 332
 333         default:
 334                 printk(KERN_INFO
 335                         "%s: unsupported NLPID 0x%02X on interface %s!\n",
 336                         wanrouter_modname, skb->data[cnt], dev->name);
 337                 return 0;
 338         }
 339         skb->protocol = ethertype;
 340         skb->pkt_type = PACKET_HOST;    /*      Physically point to point */
 341         skb_pull(skb, cnt);
 342         skb->mac.raw  = skb->data;
 343         return ethertype;
 344 }
 345
 346 #endif  /*  0  */
 347
 348 /*
 349  *      WAN device IOCTL.
 350  *      o find WAN device associated with this node
 351  *      o execute requested action or pass command to the device driver
 352  */
 353
 354 int wanrouter_ioctl(struct inode *inode, struct file *file,
 355                 unsigned int cmd, unsigned long arg)
 356 {
 357         int err = 0;
 358         struct proc_dir_entry *dent;
 359         struct wan_device *wandev;
 360         void __user *data = (void __user *)arg;
 361
 362         if (!capable(CAP_NET_ADMIN))
 363                 return -EPERM;
 364
 365         if ((cmd >> 8) != ROUTER_IOCTL)
 366                 return -EINVAL;
 367
 368         dent = PDE(inode);
 369         if ((dent == NULL) || (dent->data == NULL))
 370                 return -EINVAL;
 371
 372         wandev = dent->data;
 373         if (wandev->magic != ROUTER_MAGIC)
 374                 return -EINVAL;
 375
 376         switch (cmd) {
 377         case ROUTER_SETUP:
 378                 err = wanrouter_device_setup(wandev, data);
 379                 break;
 380
 381         case ROUTER_DOWN:
 382                 err = wanrouter_device_shutdown(wandev);
 383                 break;
 384
 385         case ROUTER_STAT:
 386                 err = wanrouter_device_stat(wandev, data);
 387                 break;
 388
 389         case ROUTER_IFNEW:
 390                 err = wanrouter_device_new_if(wandev, data);
 391                 break;
 392
 393         case ROUTER_IFDEL:
 394                 err = wanrouter_device_del_if(wandev, data);
 395                 break;
 396
 397         case ROUTER_IFSTAT:
 398                 break;
 399
 400         default:
 401                 if ((cmd >= ROUTER_USER) &&
 402                     (cmd <= ROUTER_USER_MAX) &&
 403                     wandev->ioctl)
 404                         err = wandev->ioctl(wandev, cmd, arg);
 405                 else err = -EINVAL;
 406         }
 407         return err;
 408 }
 409
 410 /*
 411  *      WAN Driver IOCTL Handlers
 412  */
 413
 414 /*
 415  *      Setup WAN link device.
 416  *      o verify user address space
 417  *      o allocate kernel memory and copy configuration data to kernel space
 418  *      o if configuration data includes extension, copy it to kernel space too
 419  *      o call driver's setup() entry point
 420  */
 421
 422 static int wanrouter_device_setup(struct wan_device *wandev,
 423                                   wandev_conf_t __user *u_conf)
 424 {
 425         void *data = NULL;
 426         wandev_conf_t *conf;
 427         int err = -EINVAL;
 428
 429         if (wandev->setup == NULL) {    /* Nothing to do ? */
 430                 printk(KERN_INFO "%s: ERROR, No setup script: wandev->setup()\n",
 431                                 wandev->name);
 432                 return 0;
 433         }
 434
 435         conf = kmalloc(sizeof(wandev_conf_t), GFP_KERNEL);
 436         if (conf == NULL){
 437                 printk(KERN_INFO "%s: ERROR, Failed to allocate kernel memory !\n",
 438                                 wandev->name);
 439                 return -ENOBUFS;
 440         }
 441
 442         if (copy_from_user(conf, u_conf, sizeof(wandev_conf_t))) {
 443                 printk(KERN_INFO "%s: Failed to copy user config data to kernel space!\n",
 444                                 wandev->name);
 445                 kfree(conf);
 446                 return -EFAULT;
 447         }
 448
 449         if (conf->magic != ROUTER_MAGIC) {
 450                 kfree(conf);
 451                 printk(KERN_INFO "%s: ERROR, Invalid MAGIC Number\n",
 452                                 wandev->name);
 453                 return -EINVAL;
 454         }
 455
 456         if (conf->data_size && conf->data) {
 457                 if (conf->data_size > 128000 || conf->data_size < 0) {
 458                         printk(KERN_INFO
 459                             "%s: ERROR, Invalid firmware data size %i !\n",
 460                                         wandev->name, conf->data_size);
 461                         kfree(conf);
 462                         return -EINVAL;
 463                 }
 464
 465                 data = vmalloc(conf->data_size);
 466                 if (!data) {
 467                         printk(KERN_INFO
 468                                 "%s: ERROR, Faild allocate kernel memory !\n",
 469                                 wandev->name);
 470                         kfree(conf);
 471                         return -ENOBUFS;
 472                 }
 473                 if (!copy_from_user(data, conf->data, conf->data_size)) {
 474                         conf->data = data;
 475                         err = wandev->setup(wandev, conf);
 476                 } else {
 477                         printk(KERN_INFO
 478                              "%s: ERROR, Faild to copy from user data !\n",
 479                                wandev->name);
 480                         err = -EFAULT;
 481                 }
 482                 vfree(data);
 483         } else {
 484                 printk(KERN_INFO
 485                     "%s: ERROR, No firmware found ! Firmware size = %i !\n",
 486                                 wandev->name, conf->data_size);
 487         }
 488
 489         kfree(conf);
 490         return err;
 491 }
 492
 493 /*
 494  *      Shutdown WAN device.
 495  *      o delete all not opened logical channels for this device
 496  *      o call driver's shutdown() entry point
 497  */
 498
 499 static int wanrouter_device_shutdown(struct wan_device *wandev)
 500 {
 501         struct net_device *dev;
 502         int err=0;
 503
 504         if (wandev->state == WAN_UNCONFIGURED)
 505                 return 0;
 506
 507         printk(KERN_INFO "\n%s: Shutting Down!\n",wandev->name);
 508
 509         for (dev = wandev->dev; dev;) {
 510                 err = wanrouter_delete_interface(wandev, dev->name);
 511                 if (err)
 512                         return err;
 513                 /* The above function deallocates the current dev
 514                  * structure. Therefore, we cannot use dev->priv
 515                  * as the next element: wandev->dev points to the
 516                  * next element */
 517                 dev = wandev->dev;
 518         }
 519
 520         if (wandev->ndev)
 521                 return -EBUSY;  /* there are opened interfaces  */
 522
 523         if (wandev->shutdown)
 524                 err=wandev->shutdown(wandev);
 525
 526         return err;
 527 }
 528
 529 /*
 530  *      Get WAN device status & statistics.
 531  */
 532
 533 static int wanrouter_device_stat(struct wan_device *wandev,
 534                                  wandev_stat_t __user *u_stat)
 535 {
 536         wandev_stat_t stat;
 537
 538         memset(&stat, 0, sizeof(stat));
 539
 540         /* Ask device driver to update device statistics */
 541         if ((wandev->state != WAN_UNCONFIGURED) && wandev->update)
 542                 wandev->update(wandev);
 543
 544         /* Fill out structure */
 545         stat.ndev  = wandev->ndev;
 546         stat.state = wandev->state;
 547
 548         if (copy_to_user(u_stat, &stat, sizeof(stat)))
 549                 return -EFAULT;
 550
 551         return 0;
 552 }
 553
 554 /*
 555  *      Create new WAN interface.
 556  *      o verify user address space
 557  *      o copy configuration data to kernel address space
 558  *      o allocate network interface data space
 559  *      o call driver's new_if() entry point
 560  *      o make sure there is no interface name conflict
 561  *      o register network interface
 562  */
 563
 564 static int wanrouter_device_new_if(struct wan_device *wandev,
 565                                    wanif_conf_t __user *u_conf)
 566 {
 567         wanif_conf_t *cnf;
 568         struct net_device *dev = NULL;
 569 #ifdef CONFIG_WANPIPE_MULTPPP
 570         struct ppp_device *pppdev=NULL;
 571 #endif
 572         int err;
 573
 574         if ((wandev->state == WAN_UNCONFIGURED) || (wandev->new_if == NULL))
 575                 return -ENODEV;
 576
 577         cnf = kmalloc(sizeof(wanif_conf_t), GFP_KERNEL);
 578         if (!cnf)
 579                 return -ENOBUFS;
 580
 581         err = -EFAULT;
 582         if (copy_from_user(cnf, u_conf, sizeof(wanif_conf_t)))
 583                 goto out;
 584
 585         err = -EINVAL;
 586         if (cnf->magic != ROUTER_MAGIC)
 587                 goto out;
 588
 589         if (cnf->config_id == WANCONFIG_MPPP) {
 590 #ifdef CONFIG_WANPIPE_MULTPPP
 591                 pppdev = kzalloc(sizeof(struct ppp_device), GFP_KERNEL);
 592                 err = -ENOBUFS;
 593                 if (pppdev == NULL)
 594                         goto out;
 595                 pppdev->dev = kzalloc(sizeof(struct net_device), GFP_KERNEL);
 596                 if (pppdev->dev == NULL) {
 597                         kfree(pppdev);
 598                         err = -ENOBUFS;
 599                         goto out;
 600                 }
 601                 err = wandev->new_if(wandev, (struct net_device *)pppdev, cnf);
 602                 dev = pppdev->dev;
 603 #else
 604                 printk(KERN_INFO "%s: Wanpipe Mulit-Port PPP support has not been compiled in!\n",
 605                                 wandev->name);
 606                 err = -EPROTONOSUPPORT;
 607                 goto out;
 608 #endif
 609         } else {
 610                 dev = kzalloc(sizeof(struct net_device), GFP_KERNEL);
 611                 err = -ENOBUFS;
 612                 if (dev == NULL)
 613                         goto out;
 614                 err = wandev->new_if(wandev, dev, cnf);
 615         }
 616
 617         if (!err) {
 618                 /* Register network interface. This will invoke init()
 619                  * function supplied by the driver.  If device registered
 620                  * successfully, add it to the interface list.
 621                  */
 622
 623                 if (dev->name == NULL) {
 624                         err = -EINVAL;
 625                 } else {
 626
 627                         #ifdef WANDEBUG
 628                         printk(KERN_INFO "%s: registering interface %s...\n",
 629                                 wanrouter_modname, dev->name);
 630                         #endif
 631
 632                         err = register_netdev(dev);
 633                         if (!err) {
 634                                 struct net_device *slave = NULL;
 635                                 unsigned long smp_flags=0;
 636
 637                                 lock_adapter_irq(&wandev->lock, &smp_flags);
 638
 639                                 if (wandev->dev == NULL) {
 640                                         wandev->dev = dev;
 641                                 } else {
 642                                         for (slave=wandev->dev;
 643                                          *((struct net_device **)slave->priv);
 644                                  slave = *((struct net_device **)slave->priv));
 645
 646                                      *((struct net_device **)slave->priv) = dev;
 647                                 }
 648                                 ++wandev->ndev;
 649
 650                                 unlock_adapter_irq(&wandev->lock, &smp_flags);
 651                                 err = 0;        /* done !!! */
 652                                 goto out;
 653                         }
 654                 }
 655                 if (wandev->del_if)
 656                         wandev->del_if(wandev, dev);
 657         }
 658
 659         /* This code has moved from del_if() function */
 660         kfree(dev->priv);
 661         dev->priv = NULL;
 662
 663 #ifdef CONFIG_WANPIPE_MULTPPP
 664         if (cnf->config_id == WANCONFIG_MPPP)
 665                 kfree(pppdev);
 666         else
 667                 kfree(dev);
 668 #else
 669         /* Sync PPP is disabled */
 670         if (cnf->config_id != WANCONFIG_MPPP)
 671                 kfree(dev);
 672 #endif
 673
 674 out:
 675         kfree(cnf);
 676         return err;
 677 }
 678
 679
 680 /*
 681  *      Delete WAN logical channel.
 682  *       o verify user address space
 683  *       o copy configuration data to kernel address space
 684  */
 685
 686 static int wanrouter_device_del_if(struct wan_device *wandev, char __user *u_name)
 687 {
 688         char name[WAN_IFNAME_SZ + 1];
 689         int err = 0;
 690
 691         if (wandev->state == WAN_UNCONFIGURED)
 692                 return -ENODEV;
 693
 694         memset(name, 0, sizeof(name));
 695
 696         if (copy_from_user(name, u_name, WAN_IFNAME_SZ))
 697                 return -EFAULT;
 698
 699         err = wanrouter_delete_interface(wandev, name);
 700         if (err)
 701                 return err;
 702
 703         /* If last interface being deleted, shutdown card
 704          * This helps with administration at leaf nodes
 705          * (You can tell if the person at the other end of the phone
 706          * has an interface configured) and avoids DoS vulnerabilities
 707          * in binary driver files - this fixes a problem with the current
 708          * Sangoma driver going into strange states when all the network
 709          * interfaces are deleted and the link irrecoverably disconnected.
 710          */
 711
 712         if (!wandev->ndev && wandev->shutdown)
 713                 err = wandev->shutdown(wandev);
 714
 715         return err;
 716 }
 717
 718 /*
 719  *      Miscellaneous Functions
 720  */
 721
 722 /*
 723  *      Find WAN device by name.
 724  *      Return pointer to the WAN device data space or NULL if device not found.
 725  */
 726
 727 static struct wan_device *wanrouter_find_device(char *name)
 728 {
 729         struct wan_device *wandev;
 730
 731         for (wandev = wanrouter_router_devlist;
 732              wandev && strcmp(wandev->name, name);
 733                 wandev = wandev->next);
 734         return wandev;
 735 }
 736
 737 /*
 738  *      Delete WAN logical channel identified by its name.
 739  *      o find logical channel by its name
 740  *      o call driver's del_if() entry point
 741  *      o unregister network interface
 742  *      o unlink channel data space from linked list of channels
 743  *      o release channel data space
 744  *
 745  *      Return: 0               success
 746  *              -ENODEV         channel not found.
 747  *              -EBUSY          interface is open
 748  *
 749  *      Note: If (force != 0), then device will be destroyed even if interface
 750  *      associated with it is open. It's caller's responsibility to make
 751  *      sure that opened interfaces are not removed!
 752  */
 753
 754 static int wanrouter_delete_interface(struct wan_device *wandev, char *name)
 755 {
 756         struct net_device *dev = NULL, *prev = NULL;
 757         unsigned long smp_flags=0;
 758
 759         lock_adapter_irq(&wandev->lock, &smp_flags);
 760         dev = wandev->dev;
 761         prev = NULL;
 762         while (dev && strcmp(name, dev->name)) {
 763                 struct net_device **slave = dev->priv;
 764                 prev = dev;
 765                 dev = *slave;
 766         }
 767         unlock_adapter_irq(&wandev->lock, &smp_flags);
 768
 769         if (dev == NULL)
 770                 return -ENODEV; /* interface not found */
 771
 772         if (netif_running(dev))
 773                 return -EBUSY;  /* interface in use */
 774
 775         if (wandev->del_if)
 776                 wandev->del_if(wandev, dev);
 777
 778         lock_adapter_irq(&wandev->lock, &smp_flags);
 779         if (prev) {
 780                 struct net_device **prev_slave = prev->priv;
 781                 struct net_device **slave = dev->priv;
 782
 783                 *prev_slave = *slave;
 784         } else {
 785                 struct net_device **slave = dev->priv;
 786                 wandev->dev = *slave;
 787         }
 788         --wandev->ndev;
 789         unlock_adapter_irq(&wandev->lock, &smp_flags);
 790
 791         printk(KERN_INFO "%s: unregistering '%s'\n", wandev->name, dev->name);
 792
 793         /* Due to new interface linking method using dev->priv,
 794          * this code has moved from del_if() function.*/
 795         kfree(dev->priv);
 796         dev->priv=NULL;
 797
 798         unregister_netdev(dev);
 799
 800         free_netdev(dev);
 801
 802         return 0;
 803 }
 804
 805 static void lock_adapter_irq(spinlock_t *lock, unsigned long *smp_flags)
 806 {
 807         spin_lock_irqsave(lock, *smp_flags);
 808 }
 809
 810
 811 static void unlock_adapter_irq(spinlock_t *lock, unsigned long *smp_flags)
 812 {
 813         spin_unlock_irqrestore(lock, *smp_flags);
 814 }
 815
 816 EXPORT_SYMBOL(register_wan_device);
 817 EXPORT_SYMBOL(unregister_wan_device);
 818
 819 MODULE_LICENSE("GPL");
 820
 821 /*
 822  *      End
 823  */