root/drivers/net/dlci.c

/* */

DEFINITIONS

1. register_frad
2. unregister_frad
3. dlci_header
4. dlci_receive
5. dlci_transmit
6. dlci_add
7. dlci_del
8. dlci_config
9. dlci_ioctl
10. dlci_change_mtu
11. dlci_open
12. dlci_close
13. dlci_get_stats
14. dlci_init
15. dlci_setup
16. init_module
17. cleanup_module

   1 /*
   2  * DLCI         Implementation of Frame Relay protocol for Linux, according to
   3  *              RFC 1490.  This generic device provides en/decapsulation for an
   4  *              underlying hardware driver.  Routes & IPs are assigned to these
   5  *              interfaces.  Requires 'dlcicfg' program to create usable 
   6  *              interfaces, the initial one, 'dlci' is for IOCTL use only.
   7  *
   8  * Version:     @(#)dlci.c      0.10    23 Mar 1996
   9  *
  10  * Author:      Mike McLagan <mike.mclagan@linux.org>
  11  *
  12  *              This program is free software; you can redistribute it and/or
  13  *              modify it under the terms of the GNU General Public License
  14  *              as published by the Free Software Foundation; either version
  15  *              2 of the License, or (at your option) any later version.
  16  */
  17 
  18 #include <linux/module.h>
  19 
  20 #include <linux/kernel.h>
  21 #include <linux/sched.h>
  22 #include <linux/types.h>
  23 #include <linux/fcntl.h>
  24 #include <linux/interrupt.h>
  25 #include <linux/ptrace.h>
  26 #include <linux/ioport.h>
  27 #include <linux/in.h>
  28 #include <linux/malloc.h>
  29 #include <linux/string.h>
  30 #include <asm/system.h>
  31 #include <asm/bitops.h>
  32 #include <asm/io.h>
  33 #include <asm/dma.h>
  34 #include <linux/errno.h>
  35 
  36 #include <linux/netdevice.h>
  37 #include <linux/skbuff.h>
  38 #include <linux/if_arp.h>
  39 #include <linux/if_frad.h>
  40 
  41 #include <net/sock.h>
  42 
  43 static const char *devname = "dlci";
  44 static const char *version = "DLCI driver v0.10, 23 Mar 1996, mike.mclagan@linux.org";
  45 
  46 static struct device *open_dev[CONFIG_DLCI_COUNT];
  47 
  48 static char *basename[16];
  49 
  50 int dlci_init(struct device *dev);
  51 
  52 /* allow FRAD's to register their name as a valid FRAD */
  53 int register_frad(const char *name)
     /*  */
  54 {
  55    int i;
  56 
  57    if (!name)
  58       return(-EINVAL);
  59 
  60    for (i=0;i<sizeof(basename) / sizeof(char *);i++)
  61    {
  62       if (!basename[i])
  63          break;
  64 
  65       /* take care of multiple registrations */
  66       if (strcmp(basename[i], name) == 0)
  67          return(0);
  68    }
  69 
  70    if (i == sizeof(basename) / sizeof(char *))
  71       return(-ENOMEM);
  72 
  73    basename[i] = (char *) name;
  74 
  75    return(0);
  76 }
  77 
  78 int unregister_frad(const char *name)
     /*  */
  79 {
  80    int i;
  81 
  82    if (!name)
  83       return(-EINVAL);
  84 
  85    for (i=0;i<sizeof(basename) / sizeof(char *);i++)
  86       if (basename[i] && (strcmp(basename[i], name) == 0))
  87          break;
  88 
  89    if (i == sizeof(basename) / sizeof(char *))
  90       return(-EINVAL);
  91 
  92    basename[i] = NULL;
  93 
  94    return(0);
  95 }
  96 
  97 /* 
  98    these encapsulate the RFC 1490 requirements as well as 
  99    deal with packet transmission and reception, working with
 100    the upper network layers 
 101  */
 102 
 103 static int dlci_header(struct sk_buff *skb, struct device *dev, 
     /*  */
 104                            unsigned short type, void *daddr, void *saddr, 
 105                            unsigned len)
 106 {
 107    struct fradhdr    hdr;
 108    struct dlci_local *dlp;
 109    unsigned          hlen;
 110    char              *dest;
 111 
 112    dlp = dev->priv;
 113 
 114    hdr.control = FRAD_I_UI;
 115    switch(type)
 116    {
 117       case ETH_P_IP:
 118          hdr.pad = FRAD_P_IP;
 119          hlen = sizeof(hdr.control) + sizeof(hdr.pad);
 120          break;
 121 
 122       /* feel free to add other types, if necessary */
 123 
 124       default:
 125          hdr.pad = FRAD_P_PADDING;
 126          hdr.NLPID = FRAD_P_SNAP;
 127          memset(hdr.OUI, 0, sizeof(hdr.OUI));
 128          hdr.PID = type;
 129          hlen = sizeof(hdr);
 130          break;
 131    }
 132 
 133    dest = skb_push(skb, hlen);
 134    if (!dest)
 135       return(0);
 136 
 137    memcpy(dest, &hdr, hlen);
 138 
 139    return(hlen);
 140 }
 141 
 142 static void dlci_receive(struct sk_buff *skb, struct device *dev)
     /*  */
 143 {
 144    struct dlci_local *dlp;
 145    struct fradhdr    *hdr;
 146    int               process, header;
 147 
 148    dlp = dev->priv;
 149    hdr = (struct fradhdr *) skb->data;
 150    process = 0;
 151    header = 0;
 152    skb->dev = dev;
 153 
 154    if (hdr->control != FRAD_I_UI)
 155    {
 156       printk(KERN_NOTICE "%s: Invalid header flag 0x%02X.\n", dev->name, hdr->control);
 157       dlp->stats.rx_errors++;
 158    }
 159    else
 160       switch(hdr->pad)
 161       {
 162          case FRAD_P_PADDING:
 163             if (hdr->NLPID != FRAD_P_SNAP)
 164             {
 165                printk(KERN_NOTICE "%s: Unsupported NLPID 0x%02X.\n", dev->name, hdr->NLPID);
 166                dlp->stats.rx_errors++;
 167                break;
 168             }
 169     
 170             if (hdr->OUI[0] + hdr->OUI[1] + hdr->OUI[2] != 0)
 171             {
 172                printk(KERN_NOTICE "%s: Unsupported organizationally unique identifier 0x%02X-%02X-%02X.\n", dev->name, hdr->OUI[0], hdr->OUI[1], hdr->OUI[2]);
 173                dlp->stats.rx_errors++;
 174                break;
 175             }
 176 
 177             /* at this point, it's an EtherType frame */
 178             header = sizeof(struct fradhdr);
 179             skb->protocol = htons(hdr->PID);
 180             process = 1;
 181             break;
 182 
 183          case FRAD_P_IP:
 184             header = sizeof(hdr->control) + sizeof(hdr->pad);
 185             skb->protocol = htons(ETH_P_IP);
 186             process = 1;
 187             break;
 188 
 189          case FRAD_P_SNAP:
 190          case FRAD_P_Q933:
 191          case FRAD_P_CLNP:
 192             printk(KERN_NOTICE "%s: Unsupported NLPID 0x%02X.\n", dev->name, hdr->pad);
 193             dlp->stats.rx_errors++;
 194             break;
 195 
 196          default:
 197             printk(KERN_NOTICE "%s: Invalid pad byte 0x%02X.\n", dev->name, hdr->pad);
 198             dlp->stats.rx_errors++;
 199             break;            
 200       }
 201 
 202    if (process)
 203    {
 204       /* we've set up the protocol, so discard the header */
 205       skb->mac.raw = skb->data; 
 206       skb_pull(skb, header);
 207       netif_rx(skb);
 208       dlp->stats.rx_packets++;
 209    }
 210    else
 211       dev_kfree_skb(skb, FREE_WRITE);
 212 }
 213 
 214 static int dlci_transmit(struct sk_buff *skb, struct device *dev)
     /*  */
 215 {
 216    struct dlci_local *dlp;
 217    int               ret;
 218 
 219    ret = 0;
 220 
 221    if (!skb || !dev)
 222       return(0);
 223 
 224    if (dev->tbusy)
 225       return(1);
 226 
 227    dlp = dev->priv;
 228 
 229    if (set_bit(0, (void*)&dev->tbusy) != 0)
 230       printk(KERN_WARNING "%s: transmitter access conflict.\n", dev->name);
 231    else
 232    {
 233       ret = dlp->slave->hard_start_xmit(skb, dlp->slave); 
 234       if (ret)
 235          dlp->stats.tx_errors++;
 236       else 
 237          dlp->stats.tx_packets++;
 238 
 239       /* per Alan Cox, always return 0, let the slave free the packet */
 240       ret = 0;
 241       dev->tbusy = 0;
 242    }
 243 
 244    return(ret);
 245 }
 246 
 247 int dlci_add(struct dlci_add *new)
     /*  */
 248 {
 249    struct device       *master, *slave;
 250    struct dlci_local   *dlp;
 251    struct frad_local   *flp;
 252    struct dlci_add     dlci;
 253    int                 err, i;
 254    char                buf[10];
 255 
 256    err = verify_area(VERIFY_READ, new, sizeof(*new));
 257    if (err)
 258       return(err);
 259 
 260    memcpy_fromfs(&dlci, new, sizeof(dlci));
 261 
 262    /* validate slave device */
 263    slave = dev_get(dlci.devname);
 264    if (!slave)
 265       return(-ENODEV);
 266 
 267    if (slave->type != ARPHRD_FRAD)
 268       return(-EINVAL);
 269 
 270    /* check for registration */
 271    for (i=0;i<sizeof(basename) / sizeof(char *); i++)
 272       if ((basename[i]) && 
 273           (strncmp(dlci.devname, basename[i], strlen(basename[i])) == 0) && 
 274           (strlen(dlci.devname) > strlen(basename[i])))
 275          break;
 276 
 277    if (i == sizeof(basename) / sizeof(char *))
 278       return(-EINVAL);
 279 
 280    /* check for too many open devices : should this be dynamic ? */
 281    for(i=0;i<CONFIG_DLCI_COUNT;i++)
 282       if (!open_dev[i])
 283          break;
 284 
 285    if (i == CONFIG_DLCI_COUNT)
 286       return(-ENOSPC);  /*  #### Alan: Comments on this?? */
 287 
 288    /* create device name */
 289    sprintf(buf, "%s%02i", devname, i);
 290 
 291    master = kmalloc(sizeof(*master), GFP_KERNEL);
 292    if (!master)
 293       return(-ENOMEM);
 294 
 295    memset(master, 0, sizeof(*master));
 296    master->name = kmalloc(strlen(buf), GFP_KERNEL);
 297 
 298    if (!master->name)
 299    {
 300       kfree(master);
 301       return(-ENOMEM);
 302    }
 303 
 304    strcpy(master->name, buf);
 305    master->init = dlci_init;
 306    master->flags = 0;
 307 
 308    err = register_netdev(master);
 309    if (err < 0)
 310    {
 311       kfree(master->name);
 312       kfree(master);
 313       return(err);
 314    }
 315 
 316    *(short *)(master->dev_addr) = dlci.dlci;
 317 
 318    dlp = (struct dlci_local *) master->priv;
 319    dlp->slave = slave;
 320 
 321    flp = slave->priv;
 322    err = flp ? (*flp->assoc)(slave, master) : -EINVAL;
 323    if (err < 0)
 324    {
 325       unregister_netdev(master);
 326       kfree(master->priv);
 327       kfree(master->name);
 328       kfree(master);
 329       return(err);
 330    }
 331 
 332    memcpy_tofs(new->devname, buf, strlen(buf) + 1);
 333    open_dev[i] = master;
 334 
 335    MOD_INC_USE_COUNT;
 336 
 337    return(0);
 338 }
 339 
 340 int dlci_del(struct device *master)
     /*  */
 341 {
 342    struct dlci_local *dlp;
 343    struct frad_local *flp;
 344    struct device     *slave;
 345    int               i, err;
 346 
 347    if (master->start)
 348       return(-EBUSY);
 349 
 350    dlp = master->priv;
 351    slave = dlp->slave;
 352    flp = slave->priv;
 353 
 354    err = (*flp->deassoc)(slave, master);
 355    if (err)
 356       return(err);
 357 
 358    unregister_netdev(master);
 359 
 360    for(i=0;i<CONFIG_DLCI_COUNT;i++)
 361       if (master == open_dev[i])
 362          break;
 363 
 364    if (i<CONFIG_DLCI_COUNT)
 365       open_dev[i] = NULL;
 366 
 367    kfree(master->priv);
 368    kfree(master->name);
 369    kfree(master);
 370 
 371    MOD_DEC_USE_COUNT;
 372 
 373    return(0);
 374 }
 375 
 376 int dlci_config(struct device *dev, struct dlci_conf *conf, int get)
     /*  */
 377 {
 378    struct dlci_conf  config;
 379    struct dlci_local *dlp;
 380    struct frad_local *flp;
 381    int               err;
 382 
 383    dlp = dev->priv;
 384 
 385    flp = dlp->slave->priv;
 386 
 387    if (!get)
 388    {
 389       memcpy_fromfs(&config, conf, sizeof(struct dlci_conf));
 390       if (config.flags & ~DLCI_VALID_FLAGS)
 391          return(-EINVAL);
 392       memcpy(&dlp->config, &config, sizeof(struct dlci_conf));
 393       dlp->configured = 1;
 394    }
 395 
 396    err = (*flp->dlci_conf)(dlp->slave, dev, get);
 397    if (err)
 398       return(err);
 399 
 400    if (get)
 401       memcpy_tofs(conf, &dlp->config, sizeof(struct dlci_conf));
 402 
 403    return(0);
 404 }
 405 
 406 int dlci_ioctl(struct device *dev, struct ifreq *ifr, int cmd)
     /*  */
 407 {
 408    struct dlci_local *dlp;
 409 
 410    if (!suser())
 411       return(-EPERM);
 412 
 413    dlp = dev->priv;
 414 
 415    switch(cmd)
 416    {
 417       case DLCI_GET_SLAVE:
 418          if (!*(short *)(dev->dev_addr))
 419             return(-EINVAL);
 420 
 421          strcpy(ifr->ifr_slave, dlp->slave->name);
 422          break;
 423 
 424       case DLCI_DEVADD:
 425          /* can only add on the primary device */
 426          if (*(short *)(dev->dev_addr))
 427             return(-EINVAL);
 428 
 429          return(dlci_add((struct dlci_add *) ifr->ifr_data));
 430          break;
 431 
 432       case DLCI_DEVDEL:
 433          /* can't delete the primary device */
 434          if (!*(short *)(dev->dev_addr))
 435             return(-EINVAL);
 436 
 437          if (dev->start)
 438             return(-EBUSY);
 439 
 440          return(dlci_del(dev));
 441          break;
 442 
 443       case DLCI_GET_CONF:
 444       case DLCI_SET_CONF:
 445          if (!*(short *)(dev->dev_addr))
 446             return(-EINVAL);
 447 
 448          return(dlci_config(dev, (struct dlci_conf *) ifr->ifr_data, cmd == DLCI_GET_CONF));
 449          break;
 450 
 451       default: 
 452          return(-EOPNOTSUPP);
 453    }
 454    return(0);
 455 }
 456 
 457 static int dlci_change_mtu(struct device *dev, int new_mtu)
     /*  */
 458 {
 459    struct dlci_local *dlp;
 460 
 461    dlp = dev->priv;
 462 
 463    return((*dlp->slave->change_mtu)(dlp->slave, new_mtu));
 464 }
 465 
 466 static int dlci_open(struct device *dev)
     /*  */
 467 {
 468    struct dlci_local *dlp;
 469    struct frad_local *flp;
 470    int               err;
 471 
 472    dlp = dev->priv;
 473 
 474    if (!*(short *)(dev->dev_addr))
 475       return(-EINVAL);
 476 
 477    if (!dlp->slave->start)
 478       return(-ENOTCONN);
 479 
 480    dev->flags = 0;
 481    dev->tbusy = 0;
 482    dev->interrupt = 0;
 483    dev->start = 1;
 484 
 485    flp = dlp->slave->priv;
 486    err = (*flp->activate)(dlp->slave, dev);
 487    if (err)
 488       return(err);
 489 
 490    return 0;
 491 }
 492 
 493 static int dlci_close(struct device *dev)
     /*  */
 494 {
 495    struct dlci_local *dlp;
 496    struct frad_local *flp;
 497    int               err;
 498 
 499    dlp = dev->priv;
 500 
 501    flp = dlp->slave->priv;
 502    err = (*flp->deactivate)(dlp->slave, dev);
 503 
 504    dev->start = 0;
 505 
 506    return 0;
 507 }
 508 
 509 static struct enet_statistics *dlci_get_stats(struct device *dev)
     /*  */
 510 {
 511    struct dlci_local *dlp;
 512 
 513    dlp = dev->priv;
 514 
 515    return(&dlp->stats);
 516 }
 517 
 518 int dlci_init(struct device *dev)
     /*  */
 519 {
 520    struct dlci_local *dlp;
 521    int i;
 522 
 523    dev->priv = kmalloc(sizeof(struct dlci_local), GFP_KERNEL);
 524    if (!dev->priv)
 525       return(-ENOMEM);
 526 
 527    memset(dev->priv, 0, sizeof(struct dlci_local));
 528    dlp = dev->priv;
 529 
 530    dev->flags           = 0;
 531    dev->open            = dlci_open;
 532    dev->stop            = dlci_close;
 533    dev->do_ioctl        = dlci_ioctl;
 534    dev->hard_start_xmit = dlci_transmit;
 535    dev->hard_header     = dlci_header;
 536    dev->get_stats       = dlci_get_stats;
 537    dev->change_mtu      = dlci_change_mtu;
 538 
 539    dlp->receive         = dlci_receive;
 540 
 541    dev->type            = ARPHRD_DLCI;
 542    dev->family          = AF_INET;
 543    dev->hard_header_len = sizeof(struct fradhdr);
 544    dev->pa_alen         = sizeof(unsigned long);
 545 
 546    memset(dev->dev_addr, 0, sizeof(dev->dev_addr));
 547 
 548    for (i = 0; i < DEV_NUMBUFFS; i++) 
 549       skb_queue_head_init(&dev->buffs[i]);
 550 
 551    return(0);
 552 }
 553 
 554 int dlci_setup(void)
     /*  */
 555 {
 556    int i;
 557 
 558    printk("%s.\n", version);
 559    
 560    for(i=0;i<CONFIG_DLCI_COUNT;i++)
 561       open_dev[i] = NULL;
 562 
 563    for(i=0;i<sizeof(basename) / sizeof(char *);i++)
 564       basename[i] = NULL;
 565 
 566    return(0);
 567 }
 568 
 569 #ifdef MODULE
 570 static struct device dlci = {"dlci", 0, 0, 0, 0, 0, 0, 0, 0, 0, NULL, dlci_init, };
 571 
 572 int init_module(void)
     /*  */
 573 {
 574    dlci_setup();
 575    return(register_netdev(&dlci));
 576 }
 577 
 578 void cleanup_module(void)
     /*  */
 579 {
 580    struct dlci_local   *dlp;
 581    struct frad_local   *flp;
 582    int                 i;
 583 
 584    unregister_netdev(&dlci);
 585 
 586    for(i=0;i<CONFIG_DLCI_COUNT;i++)
 587       if (open_dev[i])
 588       {
 589          dlp = open_dev[i]->priv;
 590          flp = open_dev[i]->slave->priv;
 591 
 592          if (open_dev[i]->start)
 593          {
 594             if (flp->deactivate)
 595                (*flp->deactivate)(open_dev[i]->slave, open_dev[i]);
 596             open_dev[i]->start = 0;
 597          }
 598 
 599          (*flp->deassoc)(open_dev[i]->slave, open_dev[i]);
 600          kfree(open_dev[i]->priv);
 601          kfree(open_dev[i]->name);
 602          kfree(open_dev[i]);
 603          open_dev[i] = NULL;
 604       }
 605 
 606    if (dlci.priv)
 607       kfree(dlci.priv);
 608 }
 609 #endif /* MODULE */

/* */