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 void lock_adapter_irq(spinlock_t *lock, unsigned long *smp_flags);
  90 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 static unsigned char wanrouter_oui_ether[] = { 0x00, 0x00, 0x00 };
 108 #if 0
 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 /*
 250  *      Encapsulate packet.
 251  *
 252  *      Return: encapsulation header size
 253  *              < 0     - unsupported Ethertype
 254  *
 255  *      Notes:
 256  *      1. This function may be called on interrupt context.
 257  */
 258
 259
 260 int wanrouter_encapsulate(struct sk_buff *skb, struct net_device *dev,
 261                           unsigned short type)
 262 {
 263         int hdr_len = 0;
 264
 265         switch (type) {
 266         case ETH_P_IP:          /* IP datagram encapsulation */
 267                 hdr_len += 1;
 268                 skb_push(skb, 1);
 269                 skb->data[0] = NLPID_IP;
 270                 break;
 271
 272         case ETH_P_IPX:         /* SNAP encapsulation */
 273         case ETH_P_ARP:
 274                 hdr_len += 7;
 275                 skb_push(skb, 7);
 276                 skb->data[0] = 0;
 277                 skb->data[1] = NLPID_SNAP;
 278                 memcpy(&skb->data[2], wanrouter_oui_ether,
 279                        sizeof(wanrouter_oui_ether));
 280                 *((unsigned short*)&skb->data[5]) = htons(type);
 281                 break;
 282
 283         default:                /* Unknown packet type */
 284                 printk(KERN_INFO
 285                         "%s: unsupported Ethertype 0x%04X on interface %s!\n",
 286                         wanrouter_modname, type, dev->name);
 287                 hdr_len = -EINVAL;
 288         }
 289         return hdr_len;
 290 }
 291
 292
 293 /*
 294  *      Decapsulate packet.
 295  *
 296  *      Return: Ethertype (in network order)
 297  *                      0       unknown encapsulation
 298  *
 299  *      Notes:
 300  *      1. This function may be called on interrupt context.
 301  */
 302
 303
 304 __be16 wanrouter_type_trans(struct sk_buff *skb, struct net_device *dev)
 305 {
 306         int cnt = skb->data[0] ? 0 : 1; /* there may be a pad present */
 307         __be16 ethertype;
 308
 309         switch (skb->data[cnt]) {
 310         case NLPID_IP:          /* IP datagramm */
 311                 ethertype = htons(ETH_P_IP);
 312                 cnt += 1;
 313                 break;
 314
 315         case NLPID_SNAP:        /* SNAP encapsulation */
 316                 if (memcmp(&skb->data[cnt + 1], wanrouter_oui_ether,
 317                            sizeof(wanrouter_oui_ether))){
 318                         printk(KERN_INFO
 319                                 "%s: unsupported SNAP OUI %02X-%02X-%02X "
 320                                 "on interface %s!\n", wanrouter_modname,
 321                                 skb->data[cnt+1], skb->data[cnt+2],
 322                                 skb->data[cnt+3], dev->name);
 323                         return 0;
 324                 }
 325                 ethertype = *((__be16*)&skb->data[cnt+4]);
 326                 cnt += 6;
 327                 break;
 328
 329         /* add other protocols, e.g. CLNP, ESIS, ISIS, if needed */
 330
 331         default:
 332                 printk(KERN_INFO
 333                         "%s: unsupported NLPID 0x%02X on interface %s!\n",
 334                         wanrouter_modname, skb->data[cnt], dev->name);
 335                 return 0;
 336         }
 337         skb->protocol = ethertype;
 338         skb->pkt_type = PACKET_HOST;    /*      Physically point to point */
 339         skb_pull(skb, cnt);
 340         skb->mac.raw  = skb->data;
 341         return ethertype;
 342 }
 343
 344
 345 /*
 346  *      WAN device IOCTL.
 347  *      o find WAN device associated with this node
 348  *      o execute requested action or pass command to the device driver
 349  */
 350
 351 int wanrouter_ioctl(struct inode *inode, struct file *file,
 352                 unsigned int cmd, unsigned long arg)
 353 {
 354         int err = 0;
 355         struct proc_dir_entry *dent;
 356         struct wan_device *wandev;
 357         void __user *data = (void __user *)arg;
 358
 359         if (!capable(CAP_NET_ADMIN))
 360                 return -EPERM;
 361
 362         if ((cmd >> 8) != ROUTER_IOCTL)
 363                 return -EINVAL;
 364
 365         dent = PDE(inode);
 366         if ((dent == NULL) || (dent->data == NULL))
 367                 return -EINVAL;
 368
 369         wandev = dent->data;
 370         if (wandev->magic != ROUTER_MAGIC)
 371                 return -EINVAL;
 372
 373         switch (cmd) {
 374         case ROUTER_SETUP:
 375                 err = wanrouter_device_setup(wandev, data);
 376                 break;
 377
 378         case ROUTER_DOWN:
 379                 err = wanrouter_device_shutdown(wandev);
 380                 break;
 381
 382         case ROUTER_STAT:
 383                 err = wanrouter_device_stat(wandev, data);
 384                 break;
 385
 386         case ROUTER_IFNEW:
 387                 err = wanrouter_device_new_if(wandev, data);
 388                 break;
 389
 390         case ROUTER_IFDEL:
 391                 err = wanrouter_device_del_if(wandev, data);
 392                 break;
 393
 394         case ROUTER_IFSTAT:
 395                 break;
 396
 397         default:
 398                 if ((cmd >= ROUTER_USER) &&
 399                     (cmd <= ROUTER_USER_MAX) &&
 400                     wandev->ioctl)
 401                         err = wandev->ioctl(wandev, cmd, arg);
 402                 else err = -EINVAL;
 403         }
 404         return err;
 405 }
 406
 407 /*
 408  *      WAN Driver IOCTL Handlers
 409  */
 410
 411 /*
 412  *      Setup WAN link device.
 413  *      o verify user address space
 414  *      o allocate kernel memory and copy configuration data to kernel space
 415  *      o if configuration data includes extension, copy it to kernel space too
 416  *      o call driver's setup() entry point
 417  */
 418
 419 static int wanrouter_device_setup(struct wan_device *wandev,
 420                                   wandev_conf_t __user *u_conf)
 421 {
 422         void *data = NULL;
 423         wandev_conf_t *conf;
 424         int err = -EINVAL;
 425
 426         if (wandev->setup == NULL) {    /* Nothing to do ? */
 427                 printk(KERN_INFO "%s: ERROR, No setup script: wandev->setup()\n",
 428                                 wandev->name);
 429                 return 0;
 430         }
 431
 432         conf = kmalloc(sizeof(wandev_conf_t), GFP_KERNEL);
 433         if (conf == NULL){
 434                 printk(KERN_INFO "%s: ERROR, Failed to allocate kernel memory !\n",
 435                                 wandev->name);
 436                 return -ENOBUFS;
 437         }
 438
 439         if (copy_from_user(conf, u_conf, sizeof(wandev_conf_t))) {
 440                 printk(KERN_INFO "%s: Failed to copy user config data to kernel space!\n",
 441                                 wandev->name);
 442                 kfree(conf);
 443                 return -EFAULT;
 444         }
 445
 446         if (conf->magic != ROUTER_MAGIC) {
 447                 kfree(conf);
 448                 printk(KERN_INFO "%s: ERROR, Invalid MAGIC Number\n",
 449                                 wandev->name);
 450                 return -EINVAL;
 451         }
 452
 453         if (conf->data_size && conf->data) {
 454                 if (conf->data_size > 128000 || conf->data_size < 0) {
 455                         printk(KERN_INFO
 456                             "%s: ERROR, Invalid firmware data size %i !\n",
 457                                         wandev->name, conf->data_size);
 458                         kfree(conf);
 459                         return -EINVAL;
 460                 }
 461
 462                 data = vmalloc(conf->data_size);
 463                 if (!data) {
 464                         printk(KERN_INFO
 465                                 "%s: ERROR, Faild allocate kernel memory !\n",
 466                                 wandev->name);
 467                         kfree(conf);
 468                         return -ENOBUFS;
 469                 }
 470                 if (!copy_from_user(data, conf->data, conf->data_size)) {
 471                         conf->data = data;
 472                         err = wandev->setup(wandev, conf);
 473                 } else {
 474                         printk(KERN_INFO
 475                              "%s: ERROR, Faild to copy from user data !\n",
 476                                wandev->name);
 477                         err = -EFAULT;
 478                 }
 479                 vfree(data);
 480         } else {
 481                 printk(KERN_INFO
 482                     "%s: ERROR, No firmware found ! Firmware size = %i !\n",
 483                                 wandev->name, conf->data_size);
 484         }
 485
 486         kfree(conf);
 487         return err;
 488 }
 489
 490 /*
 491  *      Shutdown WAN device.
 492  *      o delete all not opened logical channels for this device
 493  *      o call driver's shutdown() entry point
 494  */
 495
 496 static int wanrouter_device_shutdown(struct wan_device *wandev)
 497 {
 498         struct net_device *dev;
 499         int err=0;
 500
 501         if (wandev->state == WAN_UNCONFIGURED)
 502                 return 0;
 503
 504         printk(KERN_INFO "\n%s: Shutting Down!\n",wandev->name);
 505
 506         for (dev = wandev->dev; dev;) {
 507                 err = wanrouter_delete_interface(wandev, dev->name);
 508                 if (err)
 509                         return err;
 510                 /* The above function deallocates the current dev
 511                  * structure. Therefore, we cannot use dev->priv
 512                  * as the next element: wandev->dev points to the
 513                  * next element */
 514                 dev = wandev->dev;
 515         }
 516
 517         if (wandev->ndev)
 518                 return -EBUSY;  /* there are opened interfaces  */
 519
 520         if (wandev->shutdown)
 521                 err=wandev->shutdown(wandev);
 522
 523         return err;
 524 }
 525
 526 /*
 527  *      Get WAN device status & statistics.
 528  */
 529
 530 static int wanrouter_device_stat(struct wan_device *wandev,
 531                                  wandev_stat_t __user *u_stat)
 532 {
 533         wandev_stat_t stat;
 534
 535         memset(&stat, 0, sizeof(stat));
 536
 537         /* Ask device driver to update device statistics */
 538         if ((wandev->state != WAN_UNCONFIGURED) && wandev->update)
 539                 wandev->update(wandev);
 540
 541         /* Fill out structure */
 542         stat.ndev  = wandev->ndev;
 543         stat.state = wandev->state;
 544
 545         if (copy_to_user(u_stat, &stat, sizeof(stat)))
 546                 return -EFAULT;
 547
 548         return 0;
 549 }
 550
 551 /*
 552  *      Create new WAN interface.
 553  *      o verify user address space
 554  *      o copy configuration data to kernel address space
 555  *      o allocate network interface data space
 556  *      o call driver's new_if() entry point
 557  *      o make sure there is no interface name conflict
 558  *      o register network interface
 559  */
 560
 561 static int wanrouter_device_new_if(struct wan_device *wandev,
 562                                    wanif_conf_t __user *u_conf)
 563 {
 564         wanif_conf_t *cnf;
 565         struct net_device *dev = NULL;
 566 #ifdef CONFIG_WANPIPE_MULTPPP
 567         struct ppp_device *pppdev=NULL;
 568 #endif
 569         int err;
 570
 571         if ((wandev->state == WAN_UNCONFIGURED) || (wandev->new_if == NULL))
 572                 return -ENODEV;
 573
 574         cnf = kmalloc(sizeof(wanif_conf_t), GFP_KERNEL);
 575         if (!cnf)
 576                 return -ENOBUFS;
 577
 578         err = -EFAULT;
 579         if (copy_from_user(cnf, u_conf, sizeof(wanif_conf_t)))
 580                 goto out;
 581
 582         err = -EINVAL;
 583         if (cnf->magic != ROUTER_MAGIC)
 584                 goto out;
 585
 586         if (cnf->config_id == WANCONFIG_MPPP) {
 587 #ifdef CONFIG_WANPIPE_MULTPPP
 588                 pppdev = kzalloc(sizeof(struct ppp_device), GFP_KERNEL);
 589                 err = -ENOBUFS;
 590                 if (pppdev == NULL)
 591                         goto out;
 592                 pppdev->dev = kzalloc(sizeof(struct net_device), GFP_KERNEL);
 593                 if (pppdev->dev == NULL) {
 594                         kfree(pppdev);
 595                         err = -ENOBUFS;
 596                         goto out;
 597                 }
 598                 err = wandev->new_if(wandev, (struct net_device *)pppdev, cnf);
 599                 dev = pppdev->dev;
 600 #else
 601                 printk(KERN_INFO "%s: Wanpipe Mulit-Port PPP support has not been compiled in!\n",
 602                                 wandev->name);
 603                 err = -EPROTONOSUPPORT;
 604                 goto out;
 605 #endif
 606         } else {
 607                 dev = kzalloc(sizeof(struct net_device), GFP_KERNEL);
 608                 err = -ENOBUFS;
 609                 if (dev == NULL)
 610                         goto out;
 611                 err = wandev->new_if(wandev, dev, cnf);
 612         }
 613
 614         if (!err) {
 615                 /* Register network interface. This will invoke init()
 616                  * function supplied by the driver.  If device registered
 617                  * successfully, add it to the interface list.
 618                  */
 619
 620                 if (dev->name == NULL) {
 621                         err = -EINVAL;
 622                 } else {
 623
 624                         #ifdef WANDEBUG
 625                         printk(KERN_INFO "%s: registering interface %s...\n",
 626                                 wanrouter_modname, dev->name);
 627                         #endif
 628
 629                         err = register_netdev(dev);
 630                         if (!err) {
 631                                 struct net_device *slave = NULL;
 632                                 unsigned long smp_flags=0;
 633
 634                                 lock_adapter_irq(&wandev->lock, &smp_flags);
 635
 636                                 if (wandev->dev == NULL) {
 637                                         wandev->dev = dev;
 638                                 } else {
 639                                         for (slave=wandev->dev;
 640                                          *((struct net_device **)slave->priv);
 641                                  slave = *((struct net_device **)slave->priv));
 642
 643                                      *((struct net_device **)slave->priv) = dev;
 644                                 }
 645                                 ++wandev->ndev;
 646
 647                                 unlock_adapter_irq(&wandev->lock, &smp_flags);
 648                                 err = 0;        /* done !!! */
 649                                 goto out;
 650                         }
 651                 }
 652                 if (wandev->del_if)
 653                         wandev->del_if(wandev, dev);
 654         }
 655
 656         /* This code has moved from del_if() function */
 657         kfree(dev->priv);
 658         dev->priv = NULL;
 659
 660 #ifdef CONFIG_WANPIPE_MULTPPP
 661         if (cnf->config_id == WANCONFIG_MPPP)
 662                 kfree(pppdev);
 663         else
 664                 kfree(dev);
 665 #else
 666         /* Sync PPP is disabled */
 667         if (cnf->config_id != WANCONFIG_MPPP)
 668                 kfree(dev);
 669 #endif
 670
 671 out:
 672         kfree(cnf);
 673         return err;
 674 }
 675
 676
 677 /*
 678  *      Delete WAN logical channel.
 679  *       o verify user address space
 680  *       o copy configuration data to kernel address space
 681  */
 682
 683 static int wanrouter_device_del_if(struct wan_device *wandev, char __user *u_name)
 684 {
 685         char name[WAN_IFNAME_SZ + 1];
 686         int err = 0;
 687
 688         if (wandev->state == WAN_UNCONFIGURED)
 689                 return -ENODEV;
 690
 691         memset(name, 0, sizeof(name));
 692
 693         if (copy_from_user(name, u_name, WAN_IFNAME_SZ))
 694                 return -EFAULT;
 695
 696         err = wanrouter_delete_interface(wandev, name);
 697         if (err)
 698                 return err;
 699
 700         /* If last interface being deleted, shutdown card
 701          * This helps with administration at leaf nodes
 702          * (You can tell if the person at the other end of the phone
 703          * has an interface configured) and avoids DoS vulnerabilities
 704          * in binary driver files - this fixes a problem with the current
 705          * Sangoma driver going into strange states when all the network
 706          * interfaces are deleted and the link irrecoverably disconnected.
 707          */
 708
 709         if (!wandev->ndev && wandev->shutdown)
 710                 err = wandev->shutdown(wandev);
 711
 712         return err;
 713 }
 714
 715 /*
 716  *      Miscellaneous Functions
 717  */
 718
 719 /*
 720  *      Find WAN device by name.
 721  *      Return pointer to the WAN device data space or NULL if device not found.
 722  */
 723
 724 static struct wan_device *wanrouter_find_device(char *name)
 725 {
 726         struct wan_device *wandev;
 727
 728         for (wandev = wanrouter_router_devlist;
 729              wandev && strcmp(wandev->name, name);
 730                 wandev = wandev->next);
 731         return wandev;
 732 }
 733
 734 /*
 735  *      Delete WAN logical channel identified by its name.
 736  *      o find logical channel by its name
 737  *      o call driver's del_if() entry point
 738  *      o unregister network interface
 739  *      o unlink channel data space from linked list of channels
 740  *      o release channel data space
 741  *
 742  *      Return: 0               success
 743  *              -ENODEV         channel not found.
 744  *              -EBUSY          interface is open
 745  *
 746  *      Note: If (force != 0), then device will be destroyed even if interface
 747  *      associated with it is open. It's caller's responsibility to make
 748  *      sure that opened interfaces are not removed!
 749  */
 750
 751 static int wanrouter_delete_interface(struct wan_device *wandev, char *name)
 752 {
 753         struct net_device *dev = NULL, *prev = NULL;
 754         unsigned long smp_flags=0;
 755
 756         lock_adapter_irq(&wandev->lock, &smp_flags);
 757         dev = wandev->dev;
 758         prev = NULL;
 759         while (dev && strcmp(name, dev->name)) {
 760                 struct net_device **slave = dev->priv;
 761                 prev = dev;
 762                 dev = *slave;
 763         }
 764         unlock_adapter_irq(&wandev->lock, &smp_flags);
 765
 766         if (dev == NULL)
 767                 return -ENODEV; /* interface not found */
 768
 769         if (netif_running(dev))
 770                 return -EBUSY;  /* interface in use */
 771
 772         if (wandev->del_if)
 773                 wandev->del_if(wandev, dev);
 774
 775         lock_adapter_irq(&wandev->lock, &smp_flags);
 776         if (prev) {
 777                 struct net_device **prev_slave = prev->priv;
 778                 struct net_device **slave = dev->priv;
 779
 780                 *prev_slave = *slave;
 781         } else {
 782                 struct net_device **slave = dev->priv;
 783                 wandev->dev = *slave;
 784         }
 785         --wandev->ndev;
 786         unlock_adapter_irq(&wandev->lock, &smp_flags);
 787
 788         printk(KERN_INFO "%s: unregistering '%s'\n", wandev->name, dev->name);
 789
 790         /* Due to new interface linking method using dev->priv,
 791          * this code has moved from del_if() function.*/
 792         kfree(dev->priv);
 793         dev->priv=NULL;
 794
 795         unregister_netdev(dev);
 796
 797         free_netdev(dev);
 798
 799         return 0;
 800 }
 801
 802 void lock_adapter_irq(spinlock_t *lock, unsigned long *smp_flags)
 803 {
 804         spin_lock_irqsave(lock, *smp_flags);
 805 }
 806
 807
 808 void unlock_adapter_irq(spinlock_t *lock, unsigned long *smp_flags)
 809 {
 810         spin_unlock_irqrestore(lock, *smp_flags);
 811 }
 812
 813 EXPORT_SYMBOL(register_wan_device);
 814 EXPORT_SYMBOL(unregister_wan_device);
 815 EXPORT_SYMBOL(wanrouter_encapsulate);
 816 EXPORT_SYMBOL(wanrouter_type_trans);
 817 EXPORT_SYMBOL(lock_adapter_irq);
 818 EXPORT_SYMBOL(unlock_adapter_irq);
 819
 820 MODULE_LICENSE("GPL");
 821
 822 /*
 823  *      End
 824  */