drivers/isdn/i4l/isdn_ppp.c

   1 /* $Id: isdn_ppp.c,v 1.1.2.3 2004/02/10 01:07:13 keil Exp $
   2  *
   3  * Linux ISDN subsystem, functions for synchronous PPP (linklevel).
   4  *
   5  * Copyright 1995,96 by Michael Hipp (Michael.Hipp@student.uni-tuebingen.de)
   6  *
   7  * This software may be used and distributed according to the terms
   8  * of the GNU General Public License, incorporated herein by reference.
   9  *
  10  */
  11
  12 #include <linux/config.h>
  13 #include <linux/isdn.h>
  14 #include <linux/poll.h>
  15 #include <linux/ppp-comp.h>
  16 #ifdef CONFIG_IPPP_FILTER
  17 #include <linux/filter.h>
  18 #endif
  19
  20 #include "isdn_common.h"
  21 #include "isdn_ppp.h"
  22 #include "isdn_net.h"
  23
  24 #ifndef PPP_IPX
  25 #define PPP_IPX 0x002b
  26 #endif
  27
  28 /* Prototypes */
  29 static int isdn_ppp_fill_rq(unsigned char *buf, int len, int proto, int slot);
  30 static int isdn_ppp_closewait(int slot);
  31 static void isdn_ppp_push_higher(isdn_net_dev * net_dev, isdn_net_local * lp,
  32                                  struct sk_buff *skb, int proto);
  33 static int isdn_ppp_if_get_unit(char *namebuf);
  34 static int isdn_ppp_set_compressor(struct ippp_struct *is,struct isdn_ppp_comp_data *);
  35 static struct sk_buff *isdn_ppp_decompress(struct sk_buff *,
  36                                 struct ippp_struct *,struct ippp_struct *,int *proto);
  37 static void isdn_ppp_receive_ccp(isdn_net_dev * net_dev, isdn_net_local * lp,
  38                                 struct sk_buff *skb,int proto);
  39 static struct sk_buff *isdn_ppp_compress(struct sk_buff *skb_in,int *proto,
  40         struct ippp_struct *is,struct ippp_struct *master,int type);
  41 static void isdn_ppp_send_ccp(isdn_net_dev *net_dev, isdn_net_local *lp,
  42          struct sk_buff *skb);
  43
  44 /* New CCP stuff */
  45 static void isdn_ppp_ccp_kickup(struct ippp_struct *is);
  46 static void isdn_ppp_ccp_xmit_reset(struct ippp_struct *is, int proto,
  47                                     unsigned char code, unsigned char id,
  48                                     unsigned char *data, int len);
  49 static struct ippp_ccp_reset *isdn_ppp_ccp_reset_alloc(struct ippp_struct *is);
  50 static void isdn_ppp_ccp_reset_free(struct ippp_struct *is);
  51 static void isdn_ppp_ccp_reset_free_state(struct ippp_struct *is,
  52                                           unsigned char id);
  53 static void isdn_ppp_ccp_timer_callback(unsigned long closure);
  54 static struct ippp_ccp_reset_state *isdn_ppp_ccp_reset_alloc_state(struct ippp_struct *is,
  55                                                       unsigned char id);
  56 static void isdn_ppp_ccp_reset_trans(struct ippp_struct *is,
  57                                      struct isdn_ppp_resetparams *rp);
  58 static void isdn_ppp_ccp_reset_ack_rcvd(struct ippp_struct *is,
  59                                         unsigned char id);
  60
  61
  62
  63 #ifdef CONFIG_ISDN_MPP
  64 static ippp_bundle * isdn_ppp_bundle_arr = NULL;
  65
  66 static int isdn_ppp_mp_bundle_array_init(void);
  67 static int isdn_ppp_mp_init( isdn_net_local * lp, ippp_bundle * add_to );
  68 static void isdn_ppp_mp_receive(isdn_net_dev * net_dev, isdn_net_local * lp,
  69                                                         struct sk_buff *skb);
  70 static void isdn_ppp_mp_cleanup( isdn_net_local * lp );
  71
  72 static int isdn_ppp_bundle(struct ippp_struct *, int unit);
  73 #endif  /* CONFIG_ISDN_MPP */
  74
  75 char *isdn_ppp_revision = "$Revision: 1.1.2.3 $";
  76
  77 static struct ippp_struct *ippp_table[ISDN_MAX_CHANNELS];
  78
  79 static struct isdn_ppp_compressor *ipc_head = NULL;
  80
  81 /*
  82  * frame log (debug)
  83  */
  84 static void
  85 isdn_ppp_frame_log(char *info, char *data, int len, int maxlen,int unit,int slot)
  86 {
  87         int cnt,
  88          j,
  89          i;
  90         char buf[80];
  91
  92         if (len < maxlen)
  93                 maxlen = len;
  94
  95         for (i = 0, cnt = 0; cnt < maxlen; i++) {
  96                 for (j = 0; j < 16 && cnt < maxlen; j++, cnt++)
  97                         sprintf(buf + j * 3, "%02x ", (unsigned char) data[cnt]);
  98                 printk(KERN_DEBUG "[%d/%d].%s[%d]: %s\n",unit,slot, info, i, buf);
  99         }
 100 }
 101
 102 /*
 103  * unbind isdn_net_local <=> ippp-device
 104  * note: it can happen, that we hangup/free the master before the slaves
 105  *       in this case we bind another lp to the master device
 106  */
 107 int
 108 isdn_ppp_free(isdn_net_local * lp)
 109 {
 110         struct ippp_struct *is;
 111
 112         if (lp->ppp_slot < 0 || lp->ppp_slot > ISDN_MAX_CHANNELS) {
 113                 printk(KERN_ERR "%s: ppp_slot(%d) out of range\n",
 114                         __FUNCTION__, lp->ppp_slot);
 115                 return 0;
 116         }
 117
 118 #ifdef CONFIG_ISDN_MPP
 119         spin_lock(&lp->netdev->pb->lock);
 120 #endif
 121         isdn_net_rm_from_bundle(lp);
 122 #ifdef CONFIG_ISDN_MPP
 123         if (lp->netdev->pb->ref_ct == 1)        /* last link in queue? */
 124                 isdn_ppp_mp_cleanup(lp);
 125
 126         lp->netdev->pb->ref_ct--;
 127         spin_unlock(&lp->netdev->pb->lock);
 128 #endif /* CONFIG_ISDN_MPP */
 129         if (lp->ppp_slot < 0 || lp->ppp_slot > ISDN_MAX_CHANNELS) {
 130                 printk(KERN_ERR "%s: ppp_slot(%d) now invalid\n",
 131                         __FUNCTION__, lp->ppp_slot);
 132                 return 0;
 133         }
 134         is = ippp_table[lp->ppp_slot];
 135         if ((is->state & IPPP_CONNECT))
 136                 isdn_ppp_closewait(lp->ppp_slot);       /* force wakeup on ippp device */
 137         else if (is->state & IPPP_ASSIGNED)
 138                 is->state = IPPP_OPEN;  /* fallback to 'OPEN but not ASSIGNED' state */
 139
 140         if (is->debug & 0x1)
 141                 printk(KERN_DEBUG "isdn_ppp_free %d %lx %lx\n", lp->ppp_slot, (long) lp, (long) is->lp);
 142
 143         is->lp = NULL;          /* link is down .. set lp to NULL */
 144         lp->ppp_slot = -1;      /* is this OK ?? */
 145
 146         return 0;
 147 }
 148
 149 /*
 150  * bind isdn_net_local <=> ippp-device
 151  *
 152  * This function is allways called with holding dev->lock so
 153  * no additional lock is needed
 154  */
 155 int
 156 isdn_ppp_bind(isdn_net_local * lp)
 157 {
 158         int i;
 159         int unit = 0;
 160         struct ippp_struct *is;
 161         int retval;
 162
 163         if (lp->pppbind < 0) {  /* device bounded to ippp device ? */
 164                 isdn_net_dev *net_dev = dev->netdev;
 165                 char exclusive[ISDN_MAX_CHANNELS];      /* exclusive flags */
 166                 memset(exclusive, 0, ISDN_MAX_CHANNELS);
 167                 while (net_dev) {       /* step through net devices to find exclusive minors */
 168                         isdn_net_local *lp = net_dev->local;
 169                         if (lp->pppbind >= 0)
 170                                 exclusive[lp->pppbind] = 1;
 171                         net_dev = net_dev->next;
 172                 }
 173                 /*
 174                  * search a free device / slot
 175                  */
 176                 for (i = 0; i < ISDN_MAX_CHANNELS; i++) {
 177                         if (ippp_table[i]->state == IPPP_OPEN && !exclusive[ippp_table[i]->minor]) {    /* OPEN, but not connected! */
 178                                 break;
 179                         }
 180                 }
 181         } else {
 182                 for (i = 0; i < ISDN_MAX_CHANNELS; i++) {
 183                         if (ippp_table[i]->minor == lp->pppbind &&
 184                             (ippp_table[i]->state & IPPP_OPEN) == IPPP_OPEN)
 185                                 break;
 186                 }
 187         }
 188
 189         if (i >= ISDN_MAX_CHANNELS) {
 190                 printk(KERN_WARNING "isdn_ppp_bind: Can't find a (free) connection to the ipppd daemon.\n");
 191                 retval = -1;
 192                 goto out;
 193         }
 194         unit = isdn_ppp_if_get_unit(lp->name);  /* get unit number from interface name .. ugly! */
 195         if (unit < 0) {
 196                 printk(KERN_ERR "isdn_ppp_bind: illegal interface name %s.\n", lp->name);
 197                 retval = -1;
 198                 goto out;
 199         }
 200
 201         lp->ppp_slot = i;
 202         is = ippp_table[i];
 203         is->lp = lp;
 204         is->unit = unit;
 205         is->state = IPPP_OPEN | IPPP_ASSIGNED;  /* assigned to a netdevice but not connected */
 206 #ifdef CONFIG_ISDN_MPP
 207         retval = isdn_ppp_mp_init(lp, NULL);
 208         if (retval < 0)
 209                 goto out;
 210 #endif /* CONFIG_ISDN_MPP */
 211
 212         retval = lp->ppp_slot;
 213
 214  out:
 215         return retval;
 216 }
 217
 218 /*
 219  * kick the ipppd on the device
 220  * (wakes up daemon after B-channel connect)
 221  */
 222
 223 void
 224 isdn_ppp_wakeup_daemon(isdn_net_local * lp)
 225 {
 226         if (lp->ppp_slot < 0 || lp->ppp_slot >= ISDN_MAX_CHANNELS) {
 227                 printk(KERN_ERR "%s: ppp_slot(%d) out of range\n",
 228                         __FUNCTION__, lp->ppp_slot);
 229                 return;
 230         }
 231         ippp_table[lp->ppp_slot]->state = IPPP_OPEN | IPPP_CONNECT | IPPP_NOBLOCK;
 232         wake_up_interruptible(&ippp_table[lp->ppp_slot]->wq);
 233 }
 234
 235 /*
 236  * there was a hangup on the netdevice
 237  * force wakeup of the ippp device
 238  * go into 'device waits for release' state
 239  */
 240 static int
 241 isdn_ppp_closewait(int slot)
 242 {
 243         struct ippp_struct *is;
 244
 245         if (slot < 0 || slot >= ISDN_MAX_CHANNELS) {
 246                 printk(KERN_ERR "%s: slot(%d) out of range\n",
 247                         __FUNCTION__, slot);
 248                 return 0;
 249         }
 250         is = ippp_table[slot];
 251         if (is->state)
 252                 wake_up_interruptible(&is->wq);
 253         is->state = IPPP_CLOSEWAIT;
 254         return 1;
 255 }
 256
 257 /*
 258  * isdn_ppp_find_slot / isdn_ppp_free_slot
 259  */
 260
 261 static int
 262 isdn_ppp_get_slot(void)
 263 {
 264         int i;
 265         for (i = 0; i < ISDN_MAX_CHANNELS; i++) {
 266                 if (!ippp_table[i]->state)
 267                         return i;
 268         }
 269         return -1;
 270 }
 271
 272 /*
 273  * isdn_ppp_open
 274  */
 275
 276 int
 277 isdn_ppp_open(int min, struct file *file)
 278 {
 279         int slot;
 280         struct ippp_struct *is;
 281
 282         if (min < 0 || min > ISDN_MAX_CHANNELS)
 283                 return -ENODEV;
 284
 285         slot = isdn_ppp_get_slot();
 286         if (slot < 0) {
 287                 return -EBUSY;
 288         }
 289         is = file->private_data = ippp_table[slot];
 290
 291         printk(KERN_DEBUG "ippp, open, slot: %d, minor: %d, state: %04x\n",
 292                slot, min, is->state);
 293
 294         /* compression stuff */
 295         is->link_compressor   = is->compressor = NULL;
 296         is->link_decompressor = is->decompressor = NULL;
 297         is->link_comp_stat    = is->comp_stat = NULL;
 298         is->link_decomp_stat  = is->decomp_stat = NULL;
 299         is->compflags = 0;
 300
 301         is->reset = isdn_ppp_ccp_reset_alloc(is);
 302
 303         is->lp = NULL;
 304         is->mp_seqno = 0;       /* MP sequence number */
 305         is->pppcfg = 0;         /* ppp configuration */
 306         is->mpppcfg = 0;        /* mppp configuration */
 307         is->last_link_seqno = -1;       /* MP: maybe set to Bundle-MIN, when joining a bundle ?? */
 308         is->unit = -1;          /* set, when we have our interface */
 309         is->mru = 1524;         /* MRU, default 1524 */
 310         is->maxcid = 16;        /* VJ: maxcid */
 311         is->tk = current;
 312         init_waitqueue_head(&is->wq);
 313         is->first = is->rq + NUM_RCV_BUFFS - 1; /* receive queue */
 314         is->last = is->rq;
 315         is->minor = min;
 316 #ifdef CONFIG_ISDN_PPP_VJ
 317         /*
 318          * VJ header compression init
 319          */
 320         is->slcomp = slhc_init(16, 16); /* not necessary for 2. link in bundle */
 321 #endif
 322 #ifdef CONFIG_IPPP_FILTER
 323         is->pass_filter = NULL;
 324         is->active_filter = NULL;
 325 #endif
 326         is->state = IPPP_OPEN;
 327
 328         return 0;
 329 }
 330
 331 /*
 332  * release ippp device
 333  */
 334 void
 335 isdn_ppp_release(int min, struct file *file)
 336 {
 337         int i;
 338         struct ippp_struct *is;
 339
 340         if (min < 0 || min >= ISDN_MAX_CHANNELS)
 341                 return;
 342         is = file->private_data;
 343
 344         if (!is) {
 345                 printk(KERN_ERR "%s: no file->private_data\n", __FUNCTION__);
 346                 return;
 347         }
 348         if (is->debug & 0x1)
 349                 printk(KERN_DEBUG "ippp: release, minor: %d %lx\n", min, (long) is->lp);
 350
 351         if (is->lp) {           /* a lp address says: this link is still up */
 352                 isdn_net_dev *p = is->lp->netdev;
 353
 354                 if (!p) {
 355                         printk(KERN_ERR "%s: no lp->netdev\n", __FUNCTION__);
 356                         return;
 357                 }
 358                 is->state &= ~IPPP_CONNECT;     /* -> effect: no call of wakeup */
 359                 /*
 360                  * isdn_net_hangup() calls isdn_ppp_free()
 361                  * isdn_ppp_free() sets is->lp to NULL and lp->ppp_slot to -1
 362                  * removing the IPPP_CONNECT flag omits calling of isdn_ppp_wakeup_daemon()
 363                  */
 364                 isdn_net_hangup(&p->dev);
 365         }
 366         for (i = 0; i < NUM_RCV_BUFFS; i++) {
 367                 if (is->rq[i].buf) {
 368                         kfree(is->rq[i].buf);
 369                         is->rq[i].buf = NULL;
 370                 }
 371         }
 372         is->first = is->rq + NUM_RCV_BUFFS - 1; /* receive queue */
 373         is->last = is->rq;
 374
 375 #ifdef CONFIG_ISDN_PPP_VJ
 376 /* TODO: if this was the previous master: link the slcomp to the new master */
 377         slhc_free(is->slcomp);
 378         is->slcomp = NULL;
 379 #endif
 380 #ifdef CONFIG_IPPP_FILTER
 381         if (is->pass_filter) {
 382                 kfree(is->pass_filter);
 383                 is->pass_filter = NULL;
 384         }
 385         if (is->active_filter) {
 386                 kfree(is->active_filter);
 387                 is->active_filter = NULL;
 388         }
 389 #endif
 390
 391 /* TODO: if this was the previous master: link the stuff to the new master */
 392         if(is->comp_stat)
 393                 is->compressor->free(is->comp_stat);
 394         if(is->link_comp_stat)
 395                 is->link_compressor->free(is->link_comp_stat);
 396         if(is->link_decomp_stat)
 397                 is->link_decompressor->free(is->link_decomp_stat);
 398         if(is->decomp_stat)
 399                 is->decompressor->free(is->decomp_stat);
 400         is->compressor   = is->link_compressor   = NULL;
 401         is->decompressor = is->link_decompressor = NULL;
 402         is->comp_stat    = is->link_comp_stat    = NULL;
 403         is->decomp_stat  = is->link_decomp_stat  = NULL;
 404
 405         /* Clean up if necessary */
 406         if(is->reset)
 407                 isdn_ppp_ccp_reset_free(is);
 408
 409         /* this slot is ready for new connections */
 410         is->state = 0;
 411 }
 412
 413 /*
 414  * get_arg .. ioctl helper
 415  */
 416 static int
 417 get_arg(void __user *b, void *val, int len)
 418 {
 419         if (len <= 0)
 420                 len = sizeof(void *);
 421         if (copy_from_user(val, b, len))
 422                 return -EFAULT;
 423         return 0;
 424 }
 425
 426 /*
 427  * set arg .. ioctl helper
 428  */
 429 static int
 430 set_arg(void __user *b, void *val,int len)
 431 {
 432         if(len <= 0)
 433                 len = sizeof(void *);
 434         if (copy_to_user(b, val, len))
 435                 return -EFAULT;
 436         return 0;
 437 }
 438
 439 static int get_filter(void __user *arg, struct sock_filter **p)
 440 {
 441         struct sock_fprog uprog;
 442         struct sock_filter *code = NULL;
 443         int len, err;
 444
 445         if (copy_from_user(&uprog, arg, sizeof(uprog)))
 446                 return -EFAULT;
 447
 448         if (!uprog.len) {
 449                 *p = NULL;
 450                 return 0;
 451         }
 452
 453         /* uprog.len is unsigned short, so no overflow here */
 454         len = uprog.len * sizeof(struct sock_filter);
 455         code = kmalloc(len, GFP_KERNEL);
 456         if (code == NULL)
 457                 return -ENOMEM;
 458
 459         if (copy_from_user(code, uprog.filter, len)) {
 460                 kfree(code);
 461                 return -EFAULT;
 462         }
 463
 464         err = sk_chk_filter(code, uprog.len);
 465         if (err) {
 466                 kfree(code);
 467                 return err;
 468         }
 469
 470         *p = code;
 471         return uprog.len;
 472 }
 473
 474 /*
 475  * ippp device ioctl
 476  */
 477 int
 478 isdn_ppp_ioctl(int min, struct file *file, unsigned int cmd, unsigned long arg)
 479 {
 480         unsigned long val;
 481         int r,i,j;
 482         struct ippp_struct *is;
 483         isdn_net_local *lp;
 484         struct isdn_ppp_comp_data data;
 485         void __user *argp = (void __user *)arg;
 486
 487         is = (struct ippp_struct *) file->private_data;
 488         lp = is->lp;
 489
 490         if (is->debug & 0x1)
 491                 printk(KERN_DEBUG "isdn_ppp_ioctl: minor: %d cmd: %x state: %x\n", min, cmd, is->state);
 492
 493         if (!(is->state & IPPP_OPEN))
 494                 return -EINVAL;
 495
 496         switch (cmd) {
 497                 case PPPIOCBUNDLE:
 498 #ifdef CONFIG_ISDN_MPP
 499                         if (!(is->state & IPPP_CONNECT))
 500                                 return -EINVAL;
 501                         if ((r = get_arg(argp, &val, sizeof(val) )))
 502                                 return r;
 503                         printk(KERN_DEBUG "iPPP-bundle: minor: %d, slave unit: %d, master unit: %d\n",
 504                                (int) min, (int) is->unit, (int) val);
 505                         return isdn_ppp_bundle(is, val);
 506 #else
 507                         return -1;
 508 #endif
 509                         break;
 510                 case PPPIOCGUNIT:       /* get ppp/isdn unit number */
 511                         if ((r = set_arg(argp, &is->unit, sizeof(is->unit) )))
 512                                 return r;
 513                         break;
 514                 case PPPIOCGIFNAME:
 515                         if(!lp)
 516                                 return -EINVAL;
 517                         if ((r = set_arg(argp, lp->name, strlen(lp->name))))
 518                                 return r;
 519                         break;
 520                 case PPPIOCGMPFLAGS:    /* get configuration flags */
 521                         if ((r = set_arg(argp, &is->mpppcfg, sizeof(is->mpppcfg) )))
 522                                 return r;
 523                         break;
 524                 case PPPIOCSMPFLAGS:    /* set configuration flags */
 525                         if ((r = get_arg(argp, &val, sizeof(val) )))
 526                                 return r;
 527                         is->mpppcfg = val;
 528                         break;
 529                 case PPPIOCGFLAGS:      /* get configuration flags */
 530                         if ((r = set_arg(argp, &is->pppcfg,sizeof(is->pppcfg) )))
 531                                 return r;
 532                         break;
 533                 case PPPIOCSFLAGS:      /* set configuration flags */
 534                         if ((r = get_arg(argp, &val, sizeof(val) ))) {
 535                                 return r;
 536                         }
 537                         if (val & SC_ENABLE_IP && !(is->pppcfg & SC_ENABLE_IP) && (is->state & IPPP_CONNECT)) {
 538                                 if (lp) {
 539                                         /* OK .. we are ready to send buffers */
 540                                         is->pppcfg = val; /* isdn_ppp_xmit test for SC_ENABLE_IP !!! */
 541                                         netif_wake_queue(&lp->netdev->dev);
 542                                         break;
 543                                 }
 544                         }
 545                         is->pppcfg = val;
 546                         break;
 547                 case PPPIOCGIDLE:       /* get idle time information */
 548                         if (lp) {
 549                                 struct ppp_idle pidle;
 550                                 pidle.xmit_idle = pidle.recv_idle = lp->huptimer;
 551                                 if ((r = set_arg(argp, &pidle,sizeof(struct ppp_idle))))
 552                                          return r;
 553                         }
 554                         break;
 555                 case PPPIOCSMRU:        /* set receive unit size for PPP */
 556                         if ((r = get_arg(argp, &val, sizeof(val) )))
 557                                 return r;
 558                         is->mru = val;
 559                         break;
 560                 case PPPIOCSMPMRU:
 561                         break;
 562                 case PPPIOCSMPMTU:
 563                         break;
 564                 case PPPIOCSMAXCID:     /* set the maximum compression slot id */
 565                         if ((r = get_arg(argp, &val, sizeof(val) )))
 566                                 return r;
 567                         val++;
 568                         if (is->maxcid != val) {
 569 #ifdef CONFIG_ISDN_PPP_VJ
 570                                 struct slcompress *sltmp;
 571 #endif
 572                                 if (is->debug & 0x1)
 573                                         printk(KERN_DEBUG "ippp, ioctl: changed MAXCID to %ld\n", val);
 574                                 is->maxcid = val;
 575 #ifdef CONFIG_ISDN_PPP_VJ
 576                                 sltmp = slhc_init(16, val);
 577                                 if (!sltmp) {
 578                                         printk(KERN_ERR "ippp, can't realloc slhc struct\n");
 579                                         return -ENOMEM;
 580                                 }
 581                                 if (is->slcomp)
 582                                         slhc_free(is->slcomp);
 583                                 is->slcomp = sltmp;
 584 #endif
 585                         }
 586                         break;
 587                 case PPPIOCGDEBUG:
 588                         if ((r = set_arg(argp, &is->debug, sizeof(is->debug) )))
 589                                 return r;
 590                         break;
 591                 case PPPIOCSDEBUG:
 592                         if ((r = get_arg(argp, &val, sizeof(val) )))
 593                                 return r;
 594                         is->debug = val;
 595                         break;
 596                 case PPPIOCGCOMPRESSORS:
 597                         {
 598                                 unsigned long protos[8] = {0,};
 599                                 struct isdn_ppp_compressor *ipc = ipc_head;
 600                                 while(ipc) {
 601                                         j = ipc->num / (sizeof(long)*8);
 602                                         i = ipc->num % (sizeof(long)*8);
 603                                         if(j < 8)
 604                                                 protos[j] |= (0x1<<i);
 605                                         ipc = ipc->next;
 606                                 }
 607                                 if ((r = set_arg(argp,protos,8*sizeof(long) )))
 608                                         return r;
 609                         }
 610                         break;
 611                 case PPPIOCSCOMPRESSOR:
 612                         if ((r = get_arg(argp, &data, sizeof(struct isdn_ppp_comp_data))))
 613                                 return r;
 614                         return isdn_ppp_set_compressor(is, &data);
 615                 case PPPIOCGCALLINFO:
 616                         {
 617                                 struct pppcallinfo pci;
 618                                 memset((char *) &pci,0,sizeof(struct pppcallinfo));
 619                                 if(lp)
 620                                 {
 621                                         strncpy(pci.local_num,lp->msn,63);
 622                                         if(lp->dial) {
 623                                                 strncpy(pci.remote_num,lp->dial->num,63);
 624                                         }
 625                                         pci.charge_units = lp->charge;
 626                                         if(lp->outgoing)
 627                                                 pci.calltype = CALLTYPE_OUTGOING;
 628                                         else
 629                                                 pci.calltype = CALLTYPE_INCOMING;
 630                                         if(lp->flags & ISDN_NET_CALLBACK)
 631                                                 pci.calltype |= CALLTYPE_CALLBACK;
 632                                 }
 633                                 return set_arg(argp,&pci,sizeof(struct pppcallinfo));
 634                         }
 635 #ifdef CONFIG_IPPP_FILTER
 636                 case PPPIOCSPASS:
 637                         {
 638                                 struct sock_filter *code;
 639                                 int len = get_filter(argp, &code);
 640                                 if (len < 0)
 641                                         return len;
 642                                 kfree(is->pass_filter);
 643                                 is->pass_filter = code;
 644                                 is->pass_len = len;
 645                                 break;
 646                         }
 647                 case PPPIOCSACTIVE:
 648                         {
 649                                 struct sock_filter *code;
 650                                 int len = get_filter(argp, &code);
 651                                 if (len < 0)
 652                                         return len;
 653                                 kfree(is->active_filter);
 654                                 is->active_filter = code;
 655                                 is->active_len = len;
 656                                 break;
 657                         }
 658 #endif /* CONFIG_IPPP_FILTER */
 659                 default:
 660                         break;
 661         }
 662         return 0;
 663 }
 664
 665 unsigned int
 666 isdn_ppp_poll(struct file *file, poll_table * wait)
 667 {
 668         u_int mask;
 669         struct ippp_buf_queue *bf, *bl;
 670         u_long flags;
 671         struct ippp_struct *is;
 672
 673         is = file->private_data;
 674
 675         if (is->debug & 0x2)
 676                 printk(KERN_DEBUG "isdn_ppp_poll: minor: %d\n",
 677                                 MINOR(file->f_dentry->d_inode->i_rdev));
 678
 679         /* just registers wait_queue hook. This doesn't really wait. */
 680         poll_wait(file, &is->wq, wait);
 681
 682         if (!(is->state & IPPP_OPEN)) {
 683                 if(is->state == IPPP_CLOSEWAIT)
 684                         return POLLHUP;
 685                 printk(KERN_DEBUG "isdn_ppp: device not open\n");
 686                 return POLLERR;
 687         }
 688         /* we're always ready to send .. */
 689         mask = POLLOUT | POLLWRNORM;
 690
 691         spin_lock_irqsave(&is->buflock, flags);
 692         bl = is->last;
 693         bf = is->first;
 694         /*
 695          * if IPPP_NOBLOCK is set we return even if we have nothing to read
 696          */
 697         if (bf->next != bl || (is->state & IPPP_NOBLOCK)) {
 698                 is->state &= ~IPPP_NOBLOCK;
 699                 mask |= POLLIN | POLLRDNORM;
 700         }
 701         spin_unlock_irqrestore(&is->buflock, flags);
 702         return mask;
 703 }
 704
 705 /*
 706  *  fill up isdn_ppp_read() queue ..
 707  */
 708
 709 static int
 710 isdn_ppp_fill_rq(unsigned char *buf, int len, int proto, int slot)
 711 {
 712         struct ippp_buf_queue *bf, *bl;
 713         u_long flags;
 714         u_char *nbuf;
 715         struct ippp_struct *is;
 716
 717         if (slot < 0 || slot >= ISDN_MAX_CHANNELS) {
 718                 printk(KERN_WARNING "ippp: illegal slot(%d).\n", slot);
 719                 return 0;
 720         }
 721         is = ippp_table[slot];
 722
 723         if (!(is->state & IPPP_CONNECT)) {
 724                 printk(KERN_DEBUG "ippp: device not activated.\n");
 725                 return 0;
 726         }
 727         nbuf = (unsigned char *) kmalloc(len + 4, GFP_ATOMIC);
 728         if (!nbuf) {
 729                 printk(KERN_WARNING "ippp: Can't alloc buf\n");
 730                 return 0;
 731         }
 732         nbuf[0] = PPP_ALLSTATIONS;
 733         nbuf[1] = PPP_UI;
 734         nbuf[2] = proto >> 8;
 735         nbuf[3] = proto & 0xff;
 736         memcpy(nbuf + 4, buf, len);
 737
 738         spin_lock_irqsave(&is->buflock, flags);
 739         bf = is->first;
 740         bl = is->last;
 741
 742         if (bf == bl) {
 743                 printk(KERN_WARNING "ippp: Queue is full; discarding first buffer\n");
 744                 bf = bf->next;
 745                 kfree(bf->buf);
 746                 is->first = bf;
 747         }
 748         bl->buf = (char *) nbuf;
 749         bl->len = len + 4;
 750
 751         is->last = bl->next;
 752         spin_unlock_irqrestore(&is->buflock, flags);
 753         wake_up_interruptible(&is->wq);
 754         return len;
 755 }
 756
 757 /*
 758  * read() .. non-blocking: ipppd calls it only after select()
 759  *           reports, that there is data
 760  */
 761
 762 int
 763 isdn_ppp_read(int min, struct file *file, char __user *buf, int count)
 764 {
 765         struct ippp_struct *is;
 766         struct ippp_buf_queue *b;
 767         u_long flags;
 768         u_char *save_buf;
 769
 770         is = file->private_data;
 771
 772         if (!(is->state & IPPP_OPEN))
 773                 return 0;
 774
 775         if (!access_ok(VERIFY_WRITE, buf, count))
 776                 return -EFAULT;
 777
 778         spin_lock_irqsave(&is->buflock, flags);
 779         b = is->first->next;
 780         save_buf = b->buf;
 781         if (!save_buf) {
 782                 spin_unlock_irqrestore(&is->buflock, flags);
 783                 return -EAGAIN;
 784         }
 785         if (b->len < count)
 786                 count = b->len;
 787         b->buf = NULL;
 788         is->first = b;
 789
 790         spin_unlock_irqrestore(&is->buflock, flags);
 791         copy_to_user(buf, save_buf, count);
 792         kfree(save_buf);
 793
 794         return count;
 795 }
 796
 797 /*
 798  * ipppd wanna write a packet to the card .. non-blocking
 799  */
 800
 801 int
 802 isdn_ppp_write(int min, struct file *file, const char __user *buf, int count)
 803 {
 804         isdn_net_local *lp;
 805         struct ippp_struct *is;
 806         int proto;
 807         unsigned char protobuf[4];
 808
 809         is = file->private_data;
 810
 811         if (!(is->state & IPPP_CONNECT))
 812                 return 0;
 813
 814         lp = is->lp;
 815
 816         /* -> push it directly to the lowlevel interface */
 817
 818         if (!lp)
 819                 printk(KERN_DEBUG "isdn_ppp_write: lp == NULL\n");
 820         else {
 821                 /*
 822                  * Don't reset huptimer for
 823                  * LCP packets. (Echo requests).
 824                  */
 825                 if (copy_from_user(protobuf, buf, 4))
 826                         return -EFAULT;
 827                 proto = PPP_PROTOCOL(protobuf);
 828                 if (proto != PPP_LCP)
 829                         lp->huptimer = 0;
 830
 831                 if (lp->isdn_device < 0 || lp->isdn_channel < 0)
 832                         return 0;
 833
 834                 if ((dev->drv[lp->isdn_device]->flags & DRV_FLAG_RUNNING) &&
 835                         lp->dialstate == 0 &&
 836                     (lp->flags & ISDN_NET_CONNECTED)) {
 837                         unsigned short hl;
 838                         struct sk_buff *skb;
 839                         /*
 840                          * we need to reserve enought space in front of
 841                          * sk_buff. old call to dev_alloc_skb only reserved
 842                          * 16 bytes, now we are looking what the driver want
 843                          */
 844                         hl = dev->drv[lp->isdn_device]->interface->hl_hdrlen;
 845                         skb = alloc_skb(hl+count, GFP_ATOMIC);
 846                         if (!skb) {
 847                                 printk(KERN_WARNING "isdn_ppp_write: out of memory!\n");
 848                                 return count;
 849                         }
 850                         skb_reserve(skb, hl);
 851                         if (copy_from_user(skb_put(skb, count), buf, count))
 852                         {
 853                                 kfree_skb(skb);
 854                                 return -EFAULT;
 855                         }
 856                         if (is->debug & 0x40) {
 857                                 printk(KERN_DEBUG "ppp xmit: len %d\n", (int) skb->len);
 858                                 isdn_ppp_frame_log("xmit", skb->data, skb->len, 32,is->unit,lp->ppp_slot);
 859                         }
 860
 861                         isdn_ppp_send_ccp(lp->netdev,lp,skb); /* keeps CCP/compression states in sync */
 862
 863                         isdn_net_write_super(lp, skb);
 864                 }
 865         }
 866         return count;
 867 }
 868
 869 /*
 870  * init memory, structures etc.
 871  */
 872
 873 int
 874 isdn_ppp_init(void)
 875 {
 876         int i,
 877          j;
 878
 879 #ifdef CONFIG_ISDN_MPP
 880         if( isdn_ppp_mp_bundle_array_init() < 0 )
 881                 return -ENOMEM;
 882 #endif /* CONFIG_ISDN_MPP */
 883
 884         for (i = 0; i < ISDN_MAX_CHANNELS; i++) {
 885                 if (!(ippp_table[i] = (struct ippp_struct *)
 886                       kmalloc(sizeof(struct ippp_struct), GFP_KERNEL))) {
 887                         printk(KERN_WARNING "isdn_ppp_init: Could not alloc ippp_table\n");
 888                         for (j = 0; j < i; j++)
 889                                 kfree(ippp_table[j]);
 890                         return -1;
 891                 }
 892                 memset((char *) ippp_table[i], 0, sizeof(struct ippp_struct));
 893                 spin_lock_init(&ippp_table[i]->buflock);
 894                 ippp_table[i]->state = 0;
 895                 ippp_table[i]->first = ippp_table[i]->rq + NUM_RCV_BUFFS - 1;
 896                 ippp_table[i]->last = ippp_table[i]->rq;
 897
 898                 for (j = 0; j < NUM_RCV_BUFFS; j++) {
 899                         ippp_table[i]->rq[j].buf = NULL;
 900                         ippp_table[i]->rq[j].last = ippp_table[i]->rq +
 901                             (NUM_RCV_BUFFS + j - 1) % NUM_RCV_BUFFS;
 902                         ippp_table[i]->rq[j].next = ippp_table[i]->rq + (j + 1) % NUM_RCV_BUFFS;
 903                 }
 904         }
 905         return 0;
 906 }
 907
 908 void
 909 isdn_ppp_cleanup(void)
 910 {
 911         int i;
 912
 913         for (i = 0; i < ISDN_MAX_CHANNELS; i++)
 914                 kfree(ippp_table[i]);
 915
 916 #ifdef CONFIG_ISDN_MPP
 917         if (isdn_ppp_bundle_arr)
 918                 kfree(isdn_ppp_bundle_arr);
 919 #endif /* CONFIG_ISDN_MPP */
 920
 921 }
 922
 923 /*
 924  * check for address/control field and skip if allowed
 925  * retval != 0 -> discard packet silently
 926  */
 927 static int isdn_ppp_skip_ac(struct ippp_struct *is, struct sk_buff *skb)
 928 {
 929         if (skb->len < 1)
 930                 return -1;
 931
 932         if (skb->data[0] == 0xff) {
 933                 if (skb->len < 2)
 934                         return -1;
 935
 936                 if (skb->data[1] != 0x03)
 937                         return -1;
 938
 939                 // skip address/control (AC) field
 940                 skb_pull(skb, 2);
 941         } else {
 942                 if (is->pppcfg & SC_REJ_COMP_AC)
 943                         // if AC compression was not negotiated, but used, discard packet
 944                         return -1;
 945         }
 946         return 0;
 947 }
 948
 949 /*
 950  * get the PPP protocol header and pull skb
 951  * retval < 0 -> discard packet silently
 952  */
 953 static int isdn_ppp_strip_proto(struct sk_buff *skb)
 954 {
 955         int proto;
 956
 957         if (skb->len < 1)
 958                 return -1;
 959
 960         if (skb->data[0] & 0x1) {
 961                 // protocol field is compressed
 962                 proto = skb->data[0];
 963                 skb_pull(skb, 1);
 964         } else {
 965                 if (skb->len < 2)
 966                         return -1;
 967                 proto = ((int) skb->data[0] << 8) + skb->data[1];
 968                 skb_pull(skb, 2);
 969         }
 970         return proto;
 971 }
 972
 973
 974 /*
 975  * handler for incoming packets on a syncPPP interface
 976  */
 977 void isdn_ppp_receive(isdn_net_dev * net_dev, isdn_net_local * lp, struct sk_buff *skb)
 978 {
 979         struct ippp_struct *is;
 980         int slot;
 981         int proto;
 982
 983         if (net_dev->local->master)
 984                 BUG(); // we're called with the master device always
 985
 986         slot = lp->ppp_slot;
 987         if (slot < 0 || slot >= ISDN_MAX_CHANNELS) {
 988                 printk(KERN_ERR "isdn_ppp_receive: lp->ppp_slot(%d)\n",
 989                         lp->ppp_slot);
 990                 kfree_skb(skb);
 991                 return;
 992         }
 993         is = ippp_table[slot];
 994
 995         if (is->debug & 0x4) {
 996                 printk(KERN_DEBUG "ippp_receive: is:%08lx lp:%08lx slot:%d unit:%d len:%d\n",
 997                        (long)is,(long)lp,lp->ppp_slot,is->unit,(int) skb->len);
 998                 isdn_ppp_frame_log("receive", skb->data, skb->len, 32,is->unit,lp->ppp_slot);
 999         }
1000
1001         if (isdn_ppp_skip_ac(is, skb) < 0) {
1002                 kfree_skb(skb);
1003                 return;
1004         }
1005         proto = isdn_ppp_strip_proto(skb);
1006         if (proto < 0) {
1007                 kfree_skb(skb);
1008                 return;
1009         }
1010
1011 #ifdef CONFIG_ISDN_MPP
1012         if (is->compflags & SC_LINK_DECOMP_ON) {
1013                 skb = isdn_ppp_decompress(skb, is, NULL, &proto);
1014                 if (!skb) // decompression error
1015                         return;
1016         }
1017
1018         if (!(is->mpppcfg & SC_REJ_MP_PROT)) { // we agreed to receive MPPP
1019                 if (proto == PPP_MP) {
1020                         isdn_ppp_mp_receive(net_dev, lp, skb);
1021                         return;
1022                 }
1023         }
1024 #endif
1025         isdn_ppp_push_higher(net_dev, lp, skb, proto);
1026 }
1027
1028 /*
1029  * we receive a reassembled frame, MPPP has been taken care of before.
1030  * address/control and protocol have been stripped from the skb
1031  * note: net_dev has to be master net_dev
1032  */
1033 static void
1034 isdn_ppp_push_higher(isdn_net_dev * net_dev, isdn_net_local * lp, struct sk_buff *skb, int proto)
1035 {
1036         struct net_device *dev = &net_dev->dev;
1037         struct ippp_struct *is, *mis;
1038         isdn_net_local *mlp = NULL;
1039         int slot;
1040
1041         slot = lp->ppp_slot;
1042         if (slot < 0 || slot >= ISDN_MAX_CHANNELS) {
1043                 printk(KERN_ERR "isdn_ppp_push_higher: lp->ppp_slot(%d)\n",
1044                         lp->ppp_slot);
1045                 goto drop_packet;
1046         }
1047         is = ippp_table[slot];
1048
1049         if (lp->master) { // FIXME?
1050                 mlp = (isdn_net_local *) lp->master->priv;
1051                 slot = mlp->ppp_slot;
1052                 if (slot < 0 || slot > ISDN_MAX_CHANNELS) {
1053                         printk(KERN_ERR "isdn_ppp_push_higher: master->ppp_slot(%d)\n",
1054                                 lp->ppp_slot);
1055                         goto drop_packet;
1056                 }
1057         }
1058         mis = ippp_table[slot];
1059
1060         if (is->debug & 0x10) {
1061                 printk(KERN_DEBUG "push, skb %d %04x\n", (int) skb->len, proto);
1062                 isdn_ppp_frame_log("rpush", skb->data, skb->len, 32,is->unit,lp->ppp_slot);
1063         }
1064         if (mis->compflags & SC_DECOMP_ON) {
1065                 skb = isdn_ppp_decompress(skb, is, mis, &proto);
1066                 if (!skb) // decompression error
1067                         return;
1068         }
1069         switch (proto) {
1070                 case PPP_IPX:  /* untested */
1071                         if (is->debug & 0x20)
1072                                 printk(KERN_DEBUG "isdn_ppp: IPX\n");
1073                         skb->protocol = htons(ETH_P_IPX);
1074                         break;
1075                 case PPP_IP:
1076                         if (is->debug & 0x20)
1077                                 printk(KERN_DEBUG "isdn_ppp: IP\n");
1078                         skb->protocol = htons(ETH_P_IP);
1079                         break;
1080                 case PPP_COMP:
1081                 case PPP_COMPFRAG:
1082                         printk(KERN_INFO "isdn_ppp: unexpected compressed frame dropped\n");
1083                         goto drop_packet;
1084 #ifdef CONFIG_ISDN_PPP_VJ
1085                 case PPP_VJC_UNCOMP:
1086                         if (is->debug & 0x20)
1087                                 printk(KERN_DEBUG "isdn_ppp: VJC_UNCOMP\n");
1088                         if (net_dev->local->ppp_slot < 0) {
1089                                 printk(KERN_ERR "%s: net_dev->local->ppp_slot(%d) out of range\n",
1090                                         __FUNCTION__, net_dev->local->ppp_slot);
1091                                 goto drop_packet;
1092                         }
1093                         if (slhc_remember(ippp_table[net_dev->local->ppp_slot]->slcomp, skb->data, skb->len) <= 0) {
1094                                 printk(KERN_WARNING "isdn_ppp: received illegal VJC_UNCOMP frame!\n");
1095                                 goto drop_packet;
1096                         }
1097                         skb->protocol = htons(ETH_P_IP);
1098                         break;
1099                 case PPP_VJC_COMP:
1100                         if (is->debug & 0x20)
1101                                 printk(KERN_DEBUG "isdn_ppp: VJC_COMP\n");
1102                         {
1103                                 struct sk_buff *skb_old = skb;
1104                                 int pkt_len;
1105                                 skb = dev_alloc_skb(skb_old->len + 128);
1106
1107                                 if (!skb) {
1108                                         printk(KERN_WARNING "%s: Memory squeeze, dropping packet.\n", dev->name);
1109                                         skb = skb_old;
1110                                         goto drop_packet;
1111                                 }
1112                                 skb_put(skb, skb_old->len + 128);
1113                                 memcpy(skb->data, skb_old->data, skb_old->len);
1114                                 if (net_dev->local->ppp_slot < 0) {
1115                                         printk(KERN_ERR "%s: net_dev->local->ppp_slot(%d) out of range\n",
1116                                                 __FUNCTION__, net_dev->local->ppp_slot);
1117                                         goto drop_packet;
1118                                 }
1119                                 pkt_len = slhc_uncompress(ippp_table[net_dev->local->ppp_slot]->slcomp,
1120                                                 skb->data, skb_old->len);
1121                                 kfree_skb(skb_old);
1122                                 if (pkt_len < 0)
1123                                         goto drop_packet;
1124
1125                                 skb_trim(skb, pkt_len);
1126                                 skb->protocol = htons(ETH_P_IP);
1127                         }
1128                         break;
1129 #endif
1130                 case PPP_CCP:
1131                 case PPP_CCPFRAG:
1132                         isdn_ppp_receive_ccp(net_dev,lp,skb,proto);
1133                         /* Dont pop up ResetReq/Ack stuff to the daemon any
1134                            longer - the job is done already */
1135                         if(skb->data[0] == CCP_RESETREQ ||
1136                            skb->data[0] == CCP_RESETACK)
1137                                 break;
1138                         /* fall through */
1139                 default:
1140                         isdn_ppp_fill_rq(skb->data, skb->len, proto, lp->ppp_slot);     /* push data to pppd device */
1141                         kfree_skb(skb);
1142                         return;
1143         }
1144
1145 #ifdef CONFIG_IPPP_FILTER
1146         /* check if the packet passes the pass and active filters
1147          * the filter instructions are constructed assuming
1148          * a four-byte PPP header on each packet (which is still present) */
1149         skb_push(skb, 4);
1150
1151         {
1152                 u_int16_t *p = (u_int16_t *) skb->data;
1153
1154                 *p = 0; /* indicate inbound in DLT_LINUX_SLL */
1155         }
1156
1157         if (is->pass_filter
1158             && sk_run_filter(skb, is->pass_filter, is->pass_len) == 0) {
1159                 if (is->debug & 0x2)
1160                         printk(KERN_DEBUG "IPPP: inbound frame filtered.\n");
1161                 kfree_skb(skb);
1162                 return;
1163         }
1164         if (!(is->active_filter
1165               && sk_run_filter(skb, is->active_filter,
1166                                is->active_len) == 0)) {
1167                 if (is->debug & 0x2)
1168                         printk(KERN_DEBUG "IPPP: link-active filter: reseting huptimer.\n");
1169                 lp->huptimer = 0;
1170                 if (mlp)
1171                         mlp->huptimer = 0;
1172         }
1173         skb_pull(skb, 4);
1174 #else /* CONFIG_IPPP_FILTER */
1175         lp->huptimer = 0;
1176         if (mlp)
1177                 mlp->huptimer = 0;
1178 #endif /* CONFIG_IPPP_FILTER */
1179         skb->dev = dev;
1180         skb->input_dev = dev;
1181         skb->mac.raw = skb->data;
1182         netif_rx(skb);
1183         /* net_dev->local->stats.rx_packets++; done in isdn_net.c */
1184         return;
1185
1186  drop_packet:
1187         net_dev->local->stats.rx_dropped++;
1188         kfree_skb(skb);
1189 }
1190
1191 /*
1192  * isdn_ppp_skb_push ..
1193  * checks whether we have enough space at the beginning of the skb
1194  * and allocs a new SKB if necessary
1195  */
1196 static unsigned char *isdn_ppp_skb_push(struct sk_buff **skb_p,int len)
1197 {
1198         struct sk_buff *skb = *skb_p;
1199
1200         if(skb_headroom(skb) < len) {
1201                 struct sk_buff *nskb = skb_realloc_headroom(skb, len);
1202
1203                 if (!nskb) {
1204                         printk(KERN_ERR "isdn_ppp_skb_push: can't realloc headroom!\n");
1205                         dev_kfree_skb(skb);
1206                         return NULL;
1207                 }
1208                 printk(KERN_DEBUG "isdn_ppp_skb_push:under %d %d\n",skb_headroom(skb),len);
1209                 dev_kfree_skb(skb);
1210                 *skb_p = nskb;
1211                 return skb_push(nskb, len);
1212         }
1213         return skb_push(skb,len);
1214 }
1215
1216 /*
1217  * send ppp frame .. we expect a PIDCOMPressable proto --
1218  *  (here: currently always PPP_IP,PPP_VJC_COMP,PPP_VJC_UNCOMP)
1219  *
1220  * VJ compression may change skb pointer!!! .. requeue with old
1221  * skb isn't allowed!!
1222  */
1223
1224 int
1225 isdn_ppp_xmit(struct sk_buff *skb, struct net_device *netdev)
1226 {
1227         isdn_net_local *lp,*mlp;
1228         isdn_net_dev *nd;
1229         unsigned int proto = PPP_IP;     /* 0x21 */
1230         struct ippp_struct *ipt,*ipts;
1231         int slot, retval = 0;
1232
1233         mlp = (isdn_net_local *) (netdev->priv);
1234         nd = mlp->netdev;       /* get master lp */
1235
1236         slot = mlp->ppp_slot;
1237         if (slot < 0 || slot >= ISDN_MAX_CHANNELS) {
1238                 printk(KERN_ERR "isdn_ppp_xmit: lp->ppp_slot(%d)\n",
1239                         mlp->ppp_slot);
1240                 kfree_skb(skb);
1241                 goto out;
1242         }
1243         ipts = ippp_table[slot];
1244
1245         if (!(ipts->pppcfg & SC_ENABLE_IP)) {   /* PPP connected ? */
1246                 if (ipts->debug & 0x1)
1247                         printk(KERN_INFO "%s: IP frame delayed.\n", netdev->name);
1248                 retval = 1;
1249                 goto out;
1250         }
1251
1252         switch (ntohs(skb->protocol)) {
1253                 case ETH_P_IP:
1254                         proto = PPP_IP;
1255                         break;
1256                 case ETH_P_IPX:
1257                         proto = PPP_IPX;        /* untested */
1258                         break;
1259                 default:
1260                         printk(KERN_ERR "isdn_ppp: skipped unsupported protocol: %#x.\n",
1261                                skb->protocol);
1262                         dev_kfree_skb(skb);
1263                         goto out;
1264         }
1265
1266         lp = isdn_net_get_locked_lp(nd);
1267         if (!lp) {
1268                 printk(KERN_WARNING "%s: all channels busy - requeuing!\n", netdev->name);
1269                 retval = 1;
1270                 goto out;
1271         }
1272         /* we have our lp locked from now on */
1273
1274         slot = lp->ppp_slot;
1275         if (slot < 0 || slot > ISDN_MAX_CHANNELS) {
1276                 printk(KERN_ERR "isdn_ppp_xmit: lp->ppp_slot(%d)\n",
1277                         lp->ppp_slot);
1278                 kfree_skb(skb);
1279                 goto unlock;
1280         }
1281         ipt = ippp_table[slot];
1282
1283         /*
1284          * after this line .. requeueing in the device queue is no longer allowed!!!
1285          */
1286
1287         /* Pull off the fake header we stuck on earlier to keep
1288          * the fragmentation code happy.
1289          */
1290         skb_pull(skb,IPPP_MAX_HEADER);
1291
1292 #ifdef CONFIG_IPPP_FILTER
1293         /* check if we should pass this packet
1294          * the filter instructions are constructed assuming
1295          * a four-byte PPP header on each packet */
1296         skb_push(skb, 4);
1297
1298         {
1299                 u_int16_t *p = (u_int16_t *) skb->data;
1300
1301                 *p++ = htons(4); /* indicate outbound in DLT_LINUX_SLL */
1302                 *p   = htons(proto);
1303         }
1304
1305         if (ipt->pass_filter
1306             && sk_run_filter(skb, ipt->pass_filter, ipt->pass_len) == 0) {
1307                 if (ipt->debug & 0x4)
1308                         printk(KERN_DEBUG "IPPP: outbound frame filtered.\n");
1309                 kfree_skb(skb);
1310                 goto unlock;
1311         }
1312         if (!(ipt->active_filter
1313               && sk_run_filter(skb, ipt->active_filter,
1314                                ipt->active_len) == 0)) {
1315                 if (ipt->debug & 0x4)
1316                         printk(KERN_DEBUG "IPPP: link-active filter: reseting huptimer.\n");
1317                 lp->huptimer = 0;
1318         }
1319         skb_pull(skb, 4);
1320 #else /* CONFIG_IPPP_FILTER */
1321         lp->huptimer = 0;
1322 #endif /* CONFIG_IPPP_FILTER */
1323
1324         if (ipt->debug & 0x4)
1325                 printk(KERN_DEBUG "xmit skb, len %d\n", (int) skb->len);
1326         if (ipts->debug & 0x40)
1327                 isdn_ppp_frame_log("xmit0", skb->data, skb->len, 32,ipts->unit,lp->ppp_slot);
1328
1329 #ifdef CONFIG_ISDN_PPP_VJ
1330         if (proto == PPP_IP && ipts->pppcfg & SC_COMP_TCP) {    /* ipts here? probably yes, but check this again */
1331                 struct sk_buff *new_skb;
1332                 unsigned short hl;
1333                 /*
1334                  * we need to reserve enought space in front of
1335                  * sk_buff. old call to dev_alloc_skb only reserved
1336                  * 16 bytes, now we are looking what the driver want.
1337                  */
1338                 hl = dev->drv[lp->isdn_device]->interface->hl_hdrlen + IPPP_MAX_HEADER;
1339                 /*
1340                  * Note: hl might still be insufficient because the method
1341                  * above does not account for a possibible MPPP slave channel
1342                  * which had larger HL header space requirements than the
1343                  * master.
1344                  */
1345                 new_skb = alloc_skb(hl+skb->len, GFP_ATOMIC);
1346                 if (new_skb) {
1347                         u_char *buf;
1348                         int pktlen;
1349
1350                         skb_reserve(new_skb, hl);
1351                         new_skb->dev = skb->dev;
1352                         skb_put(new_skb, skb->len);
1353                         buf = skb->data;
1354
1355                         pktlen = slhc_compress(ipts->slcomp, skb->data, skb->len, new_skb->data,
1356                                  &buf, !(ipts->pppcfg & SC_NO_TCP_CCID));
1357
1358                         if (buf != skb->data) {
1359                                 if (new_skb->data != buf)
1360                                         printk(KERN_ERR "isdn_ppp: FATAL error after slhc_compress!!\n");
1361                                 dev_kfree_skb(skb);
1362                                 skb = new_skb;
1363                         } else {
1364                                 dev_kfree_skb(new_skb);
1365                         }
1366
1367                         skb_trim(skb, pktlen);
1368                         if (skb->data[0] & SL_TYPE_COMPRESSED_TCP) {    /* cslip? style -> PPP */
1369                                 proto = PPP_VJC_COMP;
1370                                 skb->data[0] ^= SL_TYPE_COMPRESSED_TCP;
1371                         } else {
1372                                 if (skb->data[0] >= SL_TYPE_UNCOMPRESSED_TCP)
1373                                         proto = PPP_VJC_UNCOMP;
1374                                 skb->data[0] = (skb->data[0] & 0x0f) | 0x40;
1375                         }
1376                 }
1377         }
1378 #endif
1379
1380         /*
1381          * normal (single link) or bundle compression
1382          */
1383         if(ipts->compflags & SC_COMP_ON) {
1384                 /* We send compressed only if both down- und upstream
1385                    compression is negotiated, that means, CCP is up */
1386                 if(ipts->compflags & SC_DECOMP_ON) {
1387                         skb = isdn_ppp_compress(skb,&proto,ipt,ipts,0);
1388                 } else {
1389                         printk(KERN_DEBUG "isdn_ppp: CCP not yet up - sending as-is\n");
1390                 }
1391         }
1392
1393         if (ipt->debug & 0x24)
1394                 printk(KERN_DEBUG "xmit2 skb, len %d, proto %04x\n", (int) skb->len, proto);
1395
1396 #ifdef CONFIG_ISDN_MPP
1397         if (ipt->mpppcfg & SC_MP_PROT) {
1398                 /* we get mp_seqno from static isdn_net_local */
1399                 long mp_seqno = ipts->mp_seqno;
1400                 ipts->mp_seqno++;
1401                 if (ipt->mpppcfg & SC_OUT_SHORT_SEQ) {
1402                         unsigned char *data = isdn_ppp_skb_push(&skb, 3);
1403                         if(!data)
1404                                 goto unlock;
1405                         mp_seqno &= 0xfff;
1406                         data[0] = MP_BEGIN_FRAG | MP_END_FRAG | ((mp_seqno >> 8) & 0xf);        /* (B)egin & (E)ndbit .. */
1407                         data[1] = mp_seqno & 0xff;
1408                         data[2] = proto;        /* PID compression */
1409                 } else {
1410                         unsigned char *data = isdn_ppp_skb_push(&skb, 5);
1411                         if(!data)
1412                                 goto unlock;
1413                         data[0] = MP_BEGIN_FRAG | MP_END_FRAG;  /* (B)egin & (E)ndbit .. */
1414                         data[1] = (mp_seqno >> 16) & 0xff;      /* sequence number: 24bit */
1415                         data[2] = (mp_seqno >> 8) & 0xff;
1416                         data[3] = (mp_seqno >> 0) & 0xff;
1417                         data[4] = proto;        /* PID compression */
1418                 }
1419                 proto = PPP_MP; /* MP Protocol, 0x003d */
1420         }
1421 #endif
1422
1423         /*
1424          * 'link in bundle' compression  ...
1425          */
1426         if(ipt->compflags & SC_LINK_COMP_ON)
1427                 skb = isdn_ppp_compress(skb,&proto,ipt,ipts,1);
1428
1429         if( (ipt->pppcfg & SC_COMP_PROT) && (proto <= 0xff) ) {
1430                 unsigned char *data = isdn_ppp_skb_push(&skb,1);
1431                 if(!data)
1432                         goto unlock;
1433                 data[0] = proto & 0xff;
1434         }
1435         else {
1436                 unsigned char *data = isdn_ppp_skb_push(&skb,2);
1437                 if(!data)
1438                         goto unlock;
1439                 data[0] = (proto >> 8) & 0xff;
1440                 data[1] = proto & 0xff;
1441         }
1442         if(!(ipt->pppcfg & SC_COMP_AC)) {
1443                 unsigned char *data = isdn_ppp_skb_push(&skb,2);
1444                 if(!data)
1445                         goto unlock;
1446                 data[0] = 0xff;    /* All Stations */
1447                 data[1] = 0x03;    /* Unnumbered information */
1448         }
1449
1450         /* tx-stats are now updated via BSENT-callback */
1451
1452         if (ipts->debug & 0x40) {
1453                 printk(KERN_DEBUG "skb xmit: len: %d\n", (int) skb->len);
1454                 isdn_ppp_frame_log("xmit", skb->data, skb->len, 32,ipt->unit,lp->ppp_slot);
1455         }
1456
1457         isdn_net_writebuf_skb(lp, skb);
1458
1459  unlock:
1460         spin_unlock_bh(&lp->xmit_lock);
1461  out:
1462         return retval;
1463 }
1464
1465 #ifdef CONFIG_IPPP_FILTER
1466 /*
1467  * check if this packet may trigger auto-dial.
1468  */
1469
1470 int isdn_ppp_autodial_filter(struct sk_buff *skb, isdn_net_local *lp)
1471 {
1472         struct ippp_struct *is = ippp_table[lp->ppp_slot];
1473         u_int16_t proto;
1474         int drop = 0;
1475
1476         switch (ntohs(skb->protocol)) {
1477         case ETH_P_IP:
1478                 proto = PPP_IP;
1479                 break;
1480         case ETH_P_IPX:
1481                 proto = PPP_IPX;
1482                 break;
1483         default:
1484                 printk(KERN_ERR "isdn_ppp_autodial_filter: unsupported protocol 0x%x.\n",
1485                        skb->protocol);
1486                 return 1;
1487         }
1488
1489         /* the filter instructions are constructed assuming
1490          * a four-byte PPP header on each packet. we have to
1491          * temporarily remove part of the fake header stuck on
1492          * earlier.
1493          */
1494         skb_pull(skb, IPPP_MAX_HEADER - 4);
1495
1496         {
1497                 u_int16_t *p = (u_int16_t *) skb->data;
1498
1499                 *p++ = htons(4);        /* indicate outbound in DLT_LINUX_SLL */
1500                 *p   = htons(proto);
1501         }
1502
1503         drop |= is->pass_filter
1504                 && sk_run_filter(skb, is->pass_filter, is->pass_len) == 0;
1505         drop |= is->active_filter
1506                 && sk_run_filter(skb, is->active_filter, is->active_len) == 0;
1507
1508         skb_push(skb, IPPP_MAX_HEADER - 4);
1509         return drop;
1510 }
1511 #endif
1512 #ifdef CONFIG_ISDN_MPP
1513
1514 /* this is _not_ rfc1990 header, but something we convert both short and long
1515  * headers to for convinience's sake:
1516  *      byte 0 is flags as in rfc1990
1517  *      bytes 1...4 is 24-bit seqence number converted to host byte order
1518  */
1519 #define MP_HEADER_LEN   5
1520
1521 #define MP_LONGSEQ_MASK         0x00ffffff
1522 #define MP_SHORTSEQ_MASK        0x00000fff
1523 #define MP_LONGSEQ_MAX          MP_LONGSEQ_MASK
1524 #define MP_SHORTSEQ_MAX         MP_SHORTSEQ_MASK
1525 #define MP_LONGSEQ_MAXBIT       ((MP_LONGSEQ_MASK+1)>>1)
1526 #define MP_SHORTSEQ_MAXBIT      ((MP_SHORTSEQ_MASK+1)>>1)
1527
1528 /* sequence-wrap safe comparisions (for long sequence)*/
1529 #define MP_LT(a,b)      ((a-b)&MP_LONGSEQ_MAXBIT)
1530 #define MP_LE(a,b)      !((b-a)&MP_LONGSEQ_MAXBIT)
1531 #define MP_GT(a,b)      ((b-a)&MP_LONGSEQ_MAXBIT)
1532 #define MP_GE(a,b)      !((a-b)&MP_LONGSEQ_MAXBIT)
1533
1534 #define MP_SEQ(f)       ((*(u32*)(f->data+1)))
1535 #define MP_FLAGS(f)     (f->data[0])
1536
1537 static int isdn_ppp_mp_bundle_array_init(void)
1538 {
1539         int i;
1540         int sz = ISDN_MAX_CHANNELS*sizeof(ippp_bundle);
1541         if( (isdn_ppp_bundle_arr = (ippp_bundle*)kmalloc(sz,
1542                                                         GFP_KERNEL)) == NULL )
1543                 return -ENOMEM;
1544         memset(isdn_ppp_bundle_arr, 0, sz);
1545         for( i = 0; i < ISDN_MAX_CHANNELS; i++ )
1546                 spin_lock_init(&isdn_ppp_bundle_arr[i].lock);
1547         return 0;
1548 }
1549
1550 static ippp_bundle * isdn_ppp_mp_bundle_alloc(void)
1551 {
1552         int i;
1553         for( i = 0; i < ISDN_MAX_CHANNELS; i++ )
1554                 if (isdn_ppp_bundle_arr[i].ref_ct <= 0)
1555                         return (isdn_ppp_bundle_arr + i);
1556         return NULL;
1557 }
1558
1559 static int isdn_ppp_mp_init( isdn_net_local * lp, ippp_bundle * add_to )
1560 {
1561         struct ippp_struct * is;
1562
1563         if (lp->ppp_slot < 0) {
1564                 printk(KERN_ERR "%s: lp->ppp_slot(%d) out of range\n",
1565                         __FUNCTION__, lp->ppp_slot);
1566                 return(-EINVAL);
1567         }
1568
1569         is = ippp_table[lp->ppp_slot];
1570         if (add_to) {
1571                 if( lp->netdev->pb )
1572                         lp->netdev->pb->ref_ct--;
1573                 lp->netdev->pb = add_to;
1574         } else {                /* first link in a bundle */
1575                 is->mp_seqno = 0;
1576                 if ((lp->netdev->pb = isdn_ppp_mp_bundle_alloc()) == NULL)
1577                         return -ENOMEM;
1578                 lp->next = lp->last = lp;       /* nobody else in a queue */
1579                 lp->netdev->pb->frags = NULL;
1580                 lp->netdev->pb->frames = 0;
1581                 lp->netdev->pb->seq = UINT_MAX;
1582         }
1583         lp->netdev->pb->ref_ct++;
1584
1585         is->last_link_seqno = 0;
1586         return 0;
1587 }
1588
1589 static u32 isdn_ppp_mp_get_seq( int short_seq,
1590                                         struct sk_buff * skb, u32 last_seq );
1591 static struct sk_buff * isdn_ppp_mp_discard( ippp_bundle * mp,
1592                         struct sk_buff * from, struct sk_buff * to );
1593 static void isdn_ppp_mp_reassembly( isdn_net_dev * net_dev, isdn_net_local * lp,
1594                                 struct sk_buff * from, struct sk_buff * to );
1595 static void isdn_ppp_mp_free_skb( ippp_bundle * mp, struct sk_buff * skb );
1596 static void isdn_ppp_mp_print_recv_pkt( int slot, struct sk_buff * skb );
1597
1598 static void isdn_ppp_mp_receive(isdn_net_dev * net_dev, isdn_net_local * lp,
1599                                                         struct sk_buff *skb)
1600 {
1601         struct ippp_struct *is;
1602         isdn_net_local * lpq;
1603         ippp_bundle * mp;
1604         isdn_mppp_stats * stats;
1605         struct sk_buff * newfrag, * frag, * start, *nextf;
1606         u32 newseq, minseq, thisseq;
1607         unsigned long flags;
1608         int slot;
1609
1610         spin_lock_irqsave(&net_dev->pb->lock, flags);
1611         mp = net_dev->pb;
1612         stats = &mp->stats;
1613         slot = lp->ppp_slot;
1614         if (slot < 0 || slot > ISDN_MAX_CHANNELS) {
1615                 printk(KERN_ERR "%s: lp->ppp_slot(%d)\n",
1616                         __FUNCTION__, lp->ppp_slot);
1617                 stats->frame_drops++;
1618                 dev_kfree_skb(skb);
1619                 spin_unlock_irqrestore(&mp->lock, flags);
1620                 return;
1621         }
1622         is = ippp_table[slot];
1623         if( ++mp->frames > stats->max_queue_len )
1624                 stats->max_queue_len = mp->frames;
1625
1626         if (is->debug & 0x8)
1627                 isdn_ppp_mp_print_recv_pkt(lp->ppp_slot, skb);
1628
1629         newseq = isdn_ppp_mp_get_seq(is->mpppcfg & SC_IN_SHORT_SEQ,
1630                                                 skb, is->last_link_seqno);
1631
1632
1633         /* if this packet seq # is less than last already processed one,
1634          * toss it right away, but check for sequence start case first
1635          */
1636         if( mp->seq > MP_LONGSEQ_MAX && (newseq & MP_LONGSEQ_MAXBIT) ) {
1637                 mp->seq = newseq;       /* the first packet: required for
1638                                          * rfc1990 non-compliant clients --
1639                                          * prevents constant packet toss */
1640         } else if( MP_LT(newseq, mp->seq) ) {
1641                 stats->frame_drops++;
1642                 isdn_ppp_mp_free_skb(mp, skb);
1643                 spin_unlock_irqrestore(&mp->lock, flags);
1644                 return;
1645         }
1646
1647         /* find the minimum received sequence number over all links */
1648         is->last_link_seqno = minseq = newseq;
1649         for (lpq = net_dev->queue;;) {
1650                 slot = lpq->ppp_slot;
1651                 if (slot < 0 || slot > ISDN_MAX_CHANNELS) {
1652                         printk(KERN_ERR "%s: lpq->ppp_slot(%d)\n",
1653                                 __FUNCTION__, lpq->ppp_slot);
1654                 } else {
1655                         u32 lls = ippp_table[slot]->last_link_seqno;
1656                         if (MP_LT(lls, minseq))
1657                                 minseq = lls;
1658                 }
1659                 if ((lpq = lpq->next) == net_dev->queue)
1660                         break;
1661         }
1662         if (MP_LT(minseq, mp->seq))
1663                 minseq = mp->seq;       /* can't go beyond already processed
1664                                          * packets */
1665         newfrag = skb;
1666
1667         /* if this new fragment is before the first one, then enqueue it now. */
1668         if ((frag = mp->frags) == NULL || MP_LT(newseq, MP_SEQ(frag))) {
1669                 newfrag->next = frag;
1670                 mp->frags = frag = newfrag;
1671                 newfrag = NULL;
1672         }
1673
1674         start = MP_FLAGS(frag) & MP_BEGIN_FRAG &&
1675                                 MP_SEQ(frag) == mp->seq ? frag : NULL;
1676
1677         /*
1678          * main fragment traversing loop
1679          *
1680          * try to accomplish several tasks:
1681          * - insert new fragment into the proper sequence slot (once that's done
1682          *   newfrag will be set to NULL)
1683          * - reassemble any complete fragment sequence (non-null 'start'
1684          *   indicates there is a continguous sequence present)
1685          * - discard any incomplete sequences that are below minseq -- due
1686          *   to the fact that sender always increment sequence number, if there
1687          *   is an incomplete sequence below minseq, no new fragments would
1688          *   come to complete such sequence and it should be discarded
1689          *
1690          * loop completes when we accomplished the following tasks:
1691          * - new fragment is inserted in the proper sequence ('newfrag' is
1692          *   set to NULL)
1693          * - we hit a gap in the sequence, so no reassembly/processing is
1694          *   possible ('start' would be set to NULL)
1695          *
1696          * algorightm for this code is derived from code in the book
1697          * 'PPP Design And Debugging' by James Carlson (Addison-Wesley)
1698          */
1699         while (start != NULL || newfrag != NULL) {
1700
1701                 thisseq = MP_SEQ(frag);
1702                 nextf = frag->next;
1703
1704                 /* drop any duplicate fragments */
1705                 if (newfrag != NULL && thisseq == newseq) {
1706                         isdn_ppp_mp_free_skb(mp, newfrag);
1707                         newfrag = NULL;
1708                 }
1709
1710                 /* insert new fragment before next element if possible. */
1711                 if (newfrag != NULL && (nextf == NULL ||
1712                                                 MP_LT(newseq, MP_SEQ(nextf)))) {
1713                         newfrag->next = nextf;
1714                         frag->next = nextf = newfrag;
1715                         newfrag = NULL;
1716                 }
1717
1718                 if (start != NULL) {
1719                         /* check for misplaced start */
1720                         if (start != frag && (MP_FLAGS(frag) & MP_BEGIN_FRAG)) {
1721                                 printk(KERN_WARNING"isdn_mppp(seq %d): new "
1722                                       "BEGIN flag with no prior END", thisseq);
1723                                 stats->seqerrs++;
1724                                 stats->frame_drops++;
1725                                 start = isdn_ppp_mp_discard(mp, start,frag);
1726                                 nextf = frag->next;
1727                         }
1728                 } else if (MP_LE(thisseq, minseq)) {
1729                         if (MP_FLAGS(frag) & MP_BEGIN_FRAG)
1730                                 start = frag;
1731                         else {
1732                                 if (MP_FLAGS(frag) & MP_END_FRAG)
1733                                         stats->frame_drops++;
1734                                 if( mp->frags == frag )
1735                                         mp->frags = nextf;
1736                                 isdn_ppp_mp_free_skb(mp, frag);
1737                                 frag = nextf;
1738                                 continue;
1739                         }
1740                 }
1741
1742                 /* if start is non-null and we have end fragment, then
1743                  * we have full reassembly sequence -- reassemble
1744                  * and process packet now
1745                  */
1746                 if (start != NULL && (MP_FLAGS(frag) & MP_END_FRAG)) {
1747                         minseq = mp->seq = (thisseq+1) & MP_LONGSEQ_MASK;
1748                         /* Reassemble the packet then dispatch it */
1749                         isdn_ppp_mp_reassembly(net_dev, lp, start, nextf);
1750
1751                         start = NULL;
1752                         frag = NULL;
1753
1754                         mp->frags = nextf;
1755                 }
1756
1757                 /* check if need to update start pointer: if we just
1758                  * reassembled the packet and sequence is contiguous
1759                  * then next fragment should be the start of new reassembly
1760                  * if sequence is contiguous, but we haven't reassembled yet,
1761                  * keep going.
1762                  * if sequence is not contiguous, either clear everyting
1763                  * below low watermark and set start to the next frag or
1764                  * clear start ptr.
1765                  */
1766                 if (nextf != NULL &&
1767                     ((thisseq+1) & MP_LONGSEQ_MASK) == MP_SEQ(nextf)) {
1768                         /* if we just reassembled and the next one is here,
1769                          * then start another reassembly. */
1770
1771                         if (frag == NULL) {
1772                                 if (MP_FLAGS(nextf) & MP_BEGIN_FRAG)
1773                                         start = nextf;
1774                                 else
1775                                 {
1776                                         printk(KERN_WARNING"isdn_mppp(seq %d):"
1777                                                 " END flag with no following "
1778                                                 "BEGIN", thisseq);
1779                                         stats->seqerrs++;
1780                                 }
1781                         }
1782
1783                 } else {
1784                         if ( nextf != NULL && frag != NULL &&
1785                                                 MP_LT(thisseq, minseq)) {
1786                                 /* we've got a break in the sequence
1787                                  * and we not at the end yet
1788                                  * and we did not just reassembled
1789                                  *(if we did, there wouldn't be anything before)
1790                                  * and we below the low watermark
1791                                  * discard all the frames below low watermark
1792                                  * and start over */
1793                                 stats->frame_drops++;
1794                                 mp->frags = isdn_ppp_mp_discard(mp,start,nextf);
1795                         }
1796                         /* break in the sequence, no reassembly */
1797                         start = NULL;
1798                 }
1799
1800                 frag = nextf;
1801         }       /* while -- main loop */
1802
1803         if (mp->frags == NULL)
1804                 mp->frags = frag;
1805
1806         /* rather straighforward way to deal with (not very) possible
1807          * queue overflow */
1808         if (mp->frames > MP_MAX_QUEUE_LEN) {
1809                 stats->overflows++;
1810                 while (mp->frames > MP_MAX_QUEUE_LEN) {
1811                         frag = mp->frags->next;
1812                         isdn_ppp_mp_free_skb(mp, mp->frags);
1813                         mp->frags = frag;
1814                 }
1815         }
1816         spin_unlock_irqrestore(&mp->lock, flags);
1817 }
1818
1819 static void isdn_ppp_mp_cleanup( isdn_net_local * lp )
1820 {
1821         struct sk_buff * frag = lp->netdev->pb->frags;
1822         struct sk_buff * nextfrag;
1823         while( frag ) {
1824                 nextfrag = frag->next;
1825                 isdn_ppp_mp_free_skb(lp->netdev->pb, frag);
1826                 frag = nextfrag;
1827         }
1828         lp->netdev->pb->frags = NULL;
1829 }
1830
1831 static u32 isdn_ppp_mp_get_seq( int short_seq,
1832                                         struct sk_buff * skb, u32 last_seq )
1833 {
1834         u32 seq;
1835         int flags = skb->data[0] & (MP_BEGIN_FRAG | MP_END_FRAG);
1836
1837         if( !short_seq )
1838         {
1839                 seq = ntohl(*(u32*)skb->data) & MP_LONGSEQ_MASK;
1840                 skb_push(skb,1);
1841         }
1842         else
1843         {
1844                 /* convert 12-bit short seq number to 24-bit long one
1845                 */
1846                 seq = ntohs(*(u16*)skb->data) & MP_SHORTSEQ_MASK;
1847
1848                 /* check for seqence wrap */
1849                 if( !(seq &  MP_SHORTSEQ_MAXBIT) &&
1850                      (last_seq &  MP_SHORTSEQ_MAXBIT) &&
1851                      (unsigned long)last_seq <= MP_LONGSEQ_MAX )
1852                         seq |= (last_seq + MP_SHORTSEQ_MAX+1) &
1853                                         (~MP_SHORTSEQ_MASK & MP_LONGSEQ_MASK);
1854                 else
1855                         seq |= last_seq & (~MP_SHORTSEQ_MASK & MP_LONGSEQ_MASK);
1856
1857                 skb_push(skb, 3);       /* put converted seqence back in skb */
1858         }
1859         *(u32*)(skb->data+1) = seq;     /* put seqence back in _host_ byte
1860                                          * order */
1861         skb->data[0] = flags;           /* restore flags */
1862         return seq;
1863 }
1864
1865 struct sk_buff * isdn_ppp_mp_discard( ippp_bundle * mp,
1866                         struct sk_buff * from, struct sk_buff * to )
1867 {
1868         if( from )
1869                 while (from != to) {
1870                         struct sk_buff * next = from->next;
1871                         isdn_ppp_mp_free_skb(mp, from);
1872                         from = next;
1873                 }
1874         return from;
1875 }
1876
1877 void isdn_ppp_mp_reassembly( isdn_net_dev * net_dev, isdn_net_local * lp,
1878                                 struct sk_buff * from, struct sk_buff * to )
1879 {
1880         ippp_bundle * mp = net_dev->pb;
1881         int proto;
1882         struct sk_buff * skb;
1883         unsigned int tot_len;
1884
1885         if (lp->ppp_slot < 0 || lp->ppp_slot >= ISDN_MAX_CHANNELS) {
1886                 printk(KERN_ERR "%s: lp->ppp_slot(%d) out of range\n",
1887                         __FUNCTION__, lp->ppp_slot);
1888                 return;
1889         }
1890         if( MP_FLAGS(from) == (MP_BEGIN_FRAG | MP_END_FRAG) ) {
1891                 if( ippp_table[lp->ppp_slot]->debug & 0x40 )
1892                         printk(KERN_DEBUG "isdn_mppp: reassembly: frame %d, "
1893                                         "len %d\n", MP_SEQ(from), from->len );
1894                 skb = from;
1895                 skb_pull(skb, MP_HEADER_LEN);
1896                 mp->frames--;
1897         } else {
1898                 struct sk_buff * frag;
1899                 int n;
1900
1901                 for(tot_len=n=0, frag=from; frag != to; frag=frag->next, n++)
1902                         tot_len += frag->len - MP_HEADER_LEN;
1903
1904                 if( ippp_table[lp->ppp_slot]->debug & 0x40 )
1905                         printk(KERN_DEBUG"isdn_mppp: reassembling frames %d "
1906                                 "to %d, len %d\n", MP_SEQ(from),
1907                                 (MP_SEQ(from)+n-1) & MP_LONGSEQ_MASK, tot_len );
1908                 if( (skb = dev_alloc_skb(tot_len)) == NULL ) {
1909                         printk(KERN_ERR "isdn_mppp: cannot allocate sk buff "
1910                                         "of size %d\n", tot_len);
1911                         isdn_ppp_mp_discard(mp, from, to);
1912                         return;
1913                 }
1914
1915                 while( from != to ) {
1916                         unsigned int len = from->len - MP_HEADER_LEN;
1917
1918                         memcpy(skb_put(skb,len), from->data+MP_HEADER_LEN, len);
1919                         frag = from->next;
1920                         isdn_ppp_mp_free_skb(mp, from);
1921                         from = frag;
1922                 }
1923         }
1924         proto = isdn_ppp_strip_proto(skb);
1925         isdn_ppp_push_higher(net_dev, lp, skb, proto);
1926 }
1927
1928 static void isdn_ppp_mp_free_skb(ippp_bundle * mp, struct sk_buff * skb)
1929 {
1930         dev_kfree_skb(skb);
1931         mp->frames--;
1932 }
1933
1934 static void isdn_ppp_mp_print_recv_pkt( int slot, struct sk_buff * skb )
1935 {
1936         printk(KERN_DEBUG "mp_recv: %d/%d -> %02x %02x %02x %02x %02x %02x\n",
1937                 slot, (int) skb->len,
1938                 (int) skb->data[0], (int) skb->data[1], (int) skb->data[2],
1939                 (int) skb->data[3], (int) skb->data[4], (int) skb->data[5]);
1940 }
1941
1942 static int
1943 isdn_ppp_bundle(struct ippp_struct *is, int unit)
1944 {
1945         char ifn[IFNAMSIZ + 1];
1946         isdn_net_dev *p;
1947         isdn_net_local *lp, *nlp;
1948         int rc;
1949         unsigned long flags;
1950
1951         sprintf(ifn, "ippp%d", unit);
1952         p = isdn_net_findif(ifn);
1953         if (!p) {
1954                 printk(KERN_ERR "ippp_bundle: cannot find %s\n", ifn);
1955                 return -EINVAL;
1956         }
1957
1958         spin_lock_irqsave(&p->pb->lock, flags);
1959
1960         nlp = is->lp;
1961         lp = p->queue;
1962         if( nlp->ppp_slot < 0 || nlp->ppp_slot >= ISDN_MAX_CHANNELS ||
1963                 lp->ppp_slot < 0 || lp->ppp_slot >= ISDN_MAX_CHANNELS ) {
1964                 printk(KERN_ERR "ippp_bundle: binding to invalid slot %d\n",
1965                         nlp->ppp_slot < 0 || nlp->ppp_slot >= ISDN_MAX_CHANNELS ?
1966                         nlp->ppp_slot : lp->ppp_slot );
1967                 rc = -EINVAL;
1968                 goto out;
1969         }
1970
1971         isdn_net_add_to_bundle(p, nlp);
1972
1973         ippp_table[nlp->ppp_slot]->unit = ippp_table[lp->ppp_slot]->unit;
1974
1975         /* maybe also SC_CCP stuff */
1976         ippp_table[nlp->ppp_slot]->pppcfg |= ippp_table[lp->ppp_slot]->pppcfg &
1977                 (SC_ENABLE_IP | SC_NO_TCP_CCID | SC_REJ_COMP_TCP);
1978         ippp_table[nlp->ppp_slot]->mpppcfg |= ippp_table[lp->ppp_slot]->mpppcfg &
1979                 (SC_MP_PROT | SC_REJ_MP_PROT | SC_OUT_SHORT_SEQ | SC_IN_SHORT_SEQ);
1980         rc = isdn_ppp_mp_init(nlp, p->pb);
1981 out:
1982         spin_unlock_irqrestore(&p->pb->lock, flags);
1983         return rc;
1984 }
1985
1986 #endif /* CONFIG_ISDN_MPP */
1987
1988 /*
1989  * network device ioctl handlers
1990  */
1991
1992 static int
1993 isdn_ppp_dev_ioctl_stats(int slot, struct ifreq *ifr, struct net_device *dev)
1994 {
1995         struct ppp_stats __user *res = ifr->ifr_data;
1996         struct ppp_stats t;
1997         isdn_net_local *lp = (isdn_net_local *) dev->priv;
1998
1999         if (!access_ok(VERIFY_WRITE, res, sizeof(struct ppp_stats)))
2000                 return -EFAULT;
2001
2002         /* build a temporary stat struct and copy it to user space */
2003
2004         memset(&t, 0, sizeof(struct ppp_stats));
2005         if (dev->flags & IFF_UP) {
2006                 t.p.ppp_ipackets = lp->stats.rx_packets;
2007                 t.p.ppp_ibytes = lp->stats.rx_bytes;
2008                 t.p.ppp_ierrors = lp->stats.rx_errors;
2009                 t.p.ppp_opackets = lp->stats.tx_packets;
2010                 t.p.ppp_obytes = lp->stats.tx_bytes;
2011                 t.p.ppp_oerrors = lp->stats.tx_errors;
2012 #ifdef CONFIG_ISDN_PPP_VJ
2013                 if (slot >= 0 && ippp_table[slot]->slcomp) {
2014                         struct slcompress *slcomp = ippp_table[slot]->slcomp;
2015                         t.vj.vjs_packets = slcomp->sls_o_compressed + slcomp->sls_o_uncompressed;
2016                         t.vj.vjs_compressed = slcomp->sls_o_compressed;
2017                         t.vj.vjs_searches = slcomp->sls_o_searches;
2018                         t.vj.vjs_misses = slcomp->sls_o_misses;
2019                         t.vj.vjs_errorin = slcomp->sls_i_error;
2020                         t.vj.vjs_tossed = slcomp->sls_i_tossed;
2021                         t.vj.vjs_uncompressedin = slcomp->sls_i_uncompressed;
2022                         t.vj.vjs_compressedin = slcomp->sls_i_compressed;
2023                 }
2024 #endif
2025         }
2026         if (copy_to_user(res, &t, sizeof(struct ppp_stats)))
2027                 return -EFAULT;
2028         return 0;
2029 }
2030
2031 int
2032 isdn_ppp_dev_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
2033 {
2034         int error=0;
2035         int len;
2036         isdn_net_local *lp = (isdn_net_local *) dev->priv;
2037
2038
2039         if (lp->p_encap != ISDN_NET_ENCAP_SYNCPPP)
2040                 return -EINVAL;
2041
2042         switch (cmd) {
2043 #define PPP_VERSION "2.3.7"
2044                 case SIOCGPPPVER:
2045                         len = strlen(PPP_VERSION) + 1;
2046                         if (copy_to_user(ifr->ifr_data, PPP_VERSION, len))
2047                                 error = -EFAULT;
2048                         break;
2049
2050                 case SIOCGPPPSTATS:
2051                         error = isdn_ppp_dev_ioctl_stats(lp->ppp_slot, ifr, dev);
2052                         break;
2053                 default:
2054                         error = -EINVAL;
2055                         break;
2056         }
2057         return error;
2058 }
2059
2060 static int
2061 isdn_ppp_if_get_unit(char *name)
2062 {
2063         int len,
2064          i,
2065          unit = 0,
2066          deci;
2067
2068         len = strlen(name);
2069
2070         if (strncmp("ippp", name, 4) || len > 8)
2071                 return -1;
2072
2073         for (i = 0, deci = 1; i < len; i++, deci *= 10) {
2074                 char a = name[len - i - 1];
2075                 if (a >= '0' && a <= '9')
2076                         unit += (a - '0') * deci;
2077                 else
2078                         break;
2079         }
2080         if (!i || len - i != 4)
2081                 unit = -1;
2082
2083         return unit;
2084 }
2085
2086
2087 int
2088 isdn_ppp_dial_slave(char *name)
2089 {
2090 #ifdef CONFIG_ISDN_MPP
2091         isdn_net_dev *ndev;
2092         isdn_net_local *lp;
2093         struct net_device *sdev;
2094
2095         if (!(ndev = isdn_net_findif(name)))
2096                 return 1;
2097         lp = ndev->local;
2098         if (!(lp->flags & ISDN_NET_CONNECTED))
2099                 return 5;
2100
2101         sdev = lp->slave;
2102         while (sdev) {
2103                 isdn_net_local *mlp = (isdn_net_local *) sdev->priv;
2104                 if (!(mlp->flags & ISDN_NET_CONNECTED))
2105                         break;
2106                 sdev = mlp->slave;
2107         }
2108         if (!sdev)
2109                 return 2;
2110
2111         isdn_net_dial_req((isdn_net_local *) sdev->priv);
2112         return 0;
2113 #else
2114         return -1;
2115 #endif
2116 }
2117
2118 int
2119 isdn_ppp_hangup_slave(char *name)
2120 {
2121 #ifdef CONFIG_ISDN_MPP
2122         isdn_net_dev *ndev;
2123         isdn_net_local *lp;
2124         struct net_device *sdev;
2125
2126         if (!(ndev = isdn_net_findif(name)))
2127                 return 1;
2128         lp = ndev->local;
2129         if (!(lp->flags & ISDN_NET_CONNECTED))
2130                 return 5;
2131
2132         sdev = lp->slave;
2133         while (sdev) {
2134                 isdn_net_local *mlp = (isdn_net_local *) sdev->priv;
2135
2136                 if (mlp->slave) { /* find last connected link in chain */
2137                         isdn_net_local *nlp = (isdn_net_local *) mlp->slave->priv;
2138
2139                         if (!(nlp->flags & ISDN_NET_CONNECTED))
2140                                 break;
2141                 } else if (mlp->flags & ISDN_NET_CONNECTED)
2142                         break;
2143
2144                 sdev = mlp->slave;
2145         }
2146         if (!sdev)
2147                 return 2;
2148
2149         isdn_net_hangup(sdev);
2150         return 0;
2151 #else
2152         return -1;
2153 #endif
2154 }
2155
2156 /*
2157  * PPP compression stuff
2158  */
2159
2160
2161 /* Push an empty CCP Data Frame up to the daemon to wake it up and let it
2162    generate a CCP Reset-Request or tear down CCP altogether */
2163
2164 static void isdn_ppp_ccp_kickup(struct ippp_struct *is)
2165 {
2166         isdn_ppp_fill_rq(NULL, 0, PPP_COMP, is->lp->ppp_slot);
2167 }
2168
2169 /* In-kernel handling of CCP Reset-Request and Reset-Ack is necessary,
2170    but absolutely nontrivial. The most abstruse problem we are facing is
2171    that the generation, reception and all the handling of timeouts and
2172    resends including proper request id management should be entirely left
2173    to the (de)compressor, but indeed is not covered by the current API to
2174    the (de)compressor. The API is a prototype version from PPP where only
2175    some (de)compressors have yet been implemented and all of them are
2176    rather simple in their reset handling. Especially, their is only one
2177    outstanding ResetAck at a time with all of them and ResetReq/-Acks do
2178    not have parameters. For this very special case it was sufficient to
2179    just return an error code from the decompressor and have a single
2180    reset() entry to communicate all the necessary information between
2181    the framework and the (de)compressor. Bad enough, LZS is different
2182    (and any other compressor may be different, too). It has multiple
2183    histories (eventually) and needs to Reset each of them independently
2184    and thus uses multiple outstanding Acks and history numbers as an
2185    additional parameter to Reqs/Acks.
2186    All that makes it harder to port the reset state engine into the
2187    kernel because it is not just the same simple one as in (i)pppd but
2188    it must be able to pass additional parameters and have multiple out-
2189    standing Acks. We are trying to achieve the impossible by handling
2190    reset transactions independent by their id. The id MUST change when
2191    the data portion changes, thus any (de)compressor who uses more than
2192    one resettable state must provide and recognize individual ids for
2193    each individual reset transaction. The framework itself does _only_
2194    differentiate them by id, because it has no other semantics like the
2195    (de)compressor might.
2196    This looks like a major redesign of the interface would be nice,
2197    but I don't have an idea how to do it better. */
2198
2199 /* Send a CCP Reset-Request or Reset-Ack directly from the kernel. This is
2200    getting that lengthy because there is no simple "send-this-frame-out"
2201    function above but every wrapper does a bit different. Hope I guess
2202    correct in this hack... */
2203
2204 static void isdn_ppp_ccp_xmit_reset(struct ippp_struct *is, int proto,
2205                                     unsigned char code, unsigned char id,
2206                                     unsigned char *data, int len)
2207 {
2208         struct sk_buff *skb;
2209         unsigned char *p;
2210         int hl;
2211         int cnt = 0;
2212         isdn_net_local *lp = is->lp;
2213
2214         /* Alloc large enough skb */
2215         hl = dev->drv[lp->isdn_device]->interface->hl_hdrlen;
2216         skb = alloc_skb(len + hl + 16,GFP_ATOMIC);
2217         if(!skb) {
2218                 printk(KERN_WARNING
2219                        "ippp: CCP cannot send reset - out of memory\n");
2220                 return;
2221         }
2222         skb_reserve(skb, hl);
2223
2224         /* We may need to stuff an address and control field first */
2225         if(!(is->pppcfg & SC_COMP_AC)) {
2226                 p = skb_put(skb, 2);
2227                 *p++ = 0xff;
2228                 *p++ = 0x03;
2229         }
2230
2231         /* Stuff proto, code, id and length */
2232         p = skb_put(skb, 6);
2233         *p++ = (proto >> 8);
2234         *p++ = (proto & 0xff);
2235         *p++ = code;
2236         *p++ = id;
2237         cnt = 4 + len;
2238         *p++ = (cnt >> 8);
2239         *p++ = (cnt & 0xff);
2240
2241         /* Now stuff remaining bytes */
2242         if(len) {
2243                 p = skb_put(skb, len);
2244                 memcpy(p, data, len);
2245         }
2246
2247         /* skb is now ready for xmit */
2248         printk(KERN_DEBUG "Sending CCP Frame:\n");
2249         isdn_ppp_frame_log("ccp-xmit", skb->data, skb->len, 32, is->unit,lp->ppp_slot);
2250
2251         isdn_net_write_super(lp, skb);
2252 }
2253
2254 /* Allocate the reset state vector */
2255 static struct ippp_ccp_reset *isdn_ppp_ccp_reset_alloc(struct ippp_struct *is)
2256 {
2257         struct ippp_ccp_reset *r;
2258         r = kmalloc(sizeof(struct ippp_ccp_reset), GFP_KERNEL);
2259         if(!r) {
2260                 printk(KERN_ERR "ippp_ccp: failed to allocate reset data"
2261                        " structure - no mem\n");
2262                 return NULL;
2263         }
2264         memset(r, 0, sizeof(struct ippp_ccp_reset));
2265         printk(KERN_DEBUG "ippp_ccp: allocated reset data structure %p\n", r);
2266         is->reset = r;
2267         return r;
2268 }
2269
2270 /* Destroy the reset state vector. Kill all pending timers first. */
2271 static void isdn_ppp_ccp_reset_free(struct ippp_struct *is)
2272 {
2273         unsigned int id;
2274
2275         printk(KERN_DEBUG "ippp_ccp: freeing reset data structure %p\n",
2276                is->reset);
2277         for(id = 0; id < 256; id++) {
2278                 if(is->reset->rs[id]) {
2279                         isdn_ppp_ccp_reset_free_state(is, (unsigned char)id);
2280                 }
2281         }
2282         kfree(is->reset);
2283         is->reset = NULL;
2284 }
2285
2286 /* Free a given state and clear everything up for later reallocation */
2287 static void isdn_ppp_ccp_reset_free_state(struct ippp_struct *is,
2288                                           unsigned char id)
2289 {
2290         struct ippp_ccp_reset_state *rs;
2291
2292         if(is->reset->rs[id]) {
2293                 printk(KERN_DEBUG "ippp_ccp: freeing state for id %d\n", id);
2294                 rs = is->reset->rs[id];
2295                 /* Make sure the kernel will not call back later */
2296                 if(rs->ta)
2297                         del_timer(&rs->timer);
2298                 is->reset->rs[id] = NULL;
2299                 kfree(rs);
2300         } else {
2301                 printk(KERN_WARNING "ippp_ccp: id %d is not allocated\n", id);
2302         }
2303 }
2304
2305 /* The timer callback function which is called when a ResetReq has timed out,
2306    aka has never been answered by a ResetAck */
2307 static void isdn_ppp_ccp_timer_callback(unsigned long closure)
2308 {
2309         struct ippp_ccp_reset_state *rs =
2310                 (struct ippp_ccp_reset_state *)closure;
2311
2312         if(!rs) {
2313                 printk(KERN_ERR "ippp_ccp: timer cb with zero closure.\n");
2314                 return;
2315         }
2316         if(rs->ta && rs->state == CCPResetSentReq) {
2317                 /* We are correct here */
2318                 if(!rs->expra) {
2319                         /* Hmm, there is no Ack really expected. We can clean
2320                            up the state now, it will be reallocated if the
2321                            decompressor insists on another reset */
2322                         rs->ta = 0;
2323                         isdn_ppp_ccp_reset_free_state(rs->is, rs->id);
2324                         return;
2325                 }
2326                 printk(KERN_DEBUG "ippp_ccp: CCP Reset timed out for id %d\n",
2327                        rs->id);
2328                 /* Push it again */
2329                 isdn_ppp_ccp_xmit_reset(rs->is, PPP_CCP, CCP_RESETREQ, rs->id,
2330                                         rs->data, rs->dlen);
2331                 /* Restart timer */
2332                 rs->timer.expires = jiffies + HZ*5;
2333                 add_timer(&rs->timer);
2334         } else {
2335                 printk(KERN_WARNING "ippp_ccp: timer cb in wrong state %d\n",
2336                        rs->state);
2337         }
2338 }
2339
2340 /* Allocate a new reset transaction state */
2341 static struct ippp_ccp_reset_state *isdn_ppp_ccp_reset_alloc_state(struct ippp_struct *is,
2342                                                       unsigned char id)
2343 {
2344         struct ippp_ccp_reset_state *rs;
2345         if(is->reset->rs[id]) {
2346                 printk(KERN_WARNING "ippp_ccp: old state exists for id %d\n",
2347                        id);
2348                 return NULL;
2349         } else {
2350                 rs = kmalloc(sizeof(struct ippp_ccp_reset_state), GFP_KERNEL);
2351                 if(!rs)
2352                         return NULL;
2353                 memset(rs, 0, sizeof(struct ippp_ccp_reset_state));
2354                 rs->state = CCPResetIdle;
2355                 rs->is = is;
2356                 rs->id = id;
2357                 rs->timer.data = (unsigned long)rs;
2358                 rs->timer.function = isdn_ppp_ccp_timer_callback;
2359                 is->reset->rs[id] = rs;
2360         }
2361         return rs;
2362 }
2363
2364
2365 /* A decompressor wants a reset with a set of parameters - do what is
2366    necessary to fulfill it */
2367 static void isdn_ppp_ccp_reset_trans(struct ippp_struct *is,
2368                                      struct isdn_ppp_resetparams *rp)
2369 {
2370         struct ippp_ccp_reset_state *rs;
2371
2372         if(rp->valid) {
2373                 /* The decompressor defines parameters by itself */
2374                 if(rp->rsend) {
2375                         /* And he wants us to send a request */
2376                         if(!(rp->idval)) {
2377                                 printk(KERN_ERR "ippp_ccp: decompressor must"
2378                                        " specify reset id\n");
2379                                 return;
2380                         }
2381                         if(is->reset->rs[rp->id]) {
2382                                 /* There is already a transaction in existence
2383                                    for this id. May be still waiting for a
2384                                    Ack or may be wrong. */
2385                                 rs = is->reset->rs[rp->id];
2386                                 if(rs->state == CCPResetSentReq && rs->ta) {
2387                                         printk(KERN_DEBUG "ippp_ccp: reset"
2388                                                " trans still in progress"
2389                                                " for id %d\n", rp->id);
2390                                 } else {
2391                                         printk(KERN_WARNING "ippp_ccp: reset"
2392                                                " trans in wrong state %d for"
2393                                                " id %d\n", rs->state, rp->id);
2394                                 }
2395                         } else {
2396                                 /* Ok, this is a new transaction */
2397                                 printk(KERN_DEBUG "ippp_ccp: new trans for id"
2398                                        " %d to be started\n", rp->id);
2399                                 rs = isdn_ppp_ccp_reset_alloc_state(is, rp->id);
2400                                 if(!rs) {
2401                                         printk(KERN_ERR "ippp_ccp: out of mem"
2402                                                " allocing ccp trans\n");
2403                                         return;
2404                                 }
2405                                 rs->state = CCPResetSentReq;
2406                                 rs->expra = rp->expra;
2407                                 if(rp->dtval) {
2408                                         rs->dlen = rp->dlen;
2409                                         memcpy(rs->data, rp->data, rp->dlen);
2410                                 }
2411                                 /* HACK TODO - add link comp here */
2412                                 isdn_ppp_ccp_xmit_reset(is, PPP_CCP,
2413                                                         CCP_RESETREQ, rs->id,
2414                                                         rs->data, rs->dlen);
2415                                 /* Start the timer */
2416                                 rs->timer.expires = jiffies + 5*HZ;
2417                                 add_timer(&rs->timer);
2418                                 rs->ta = 1;
2419                         }
2420                 } else {
2421                         printk(KERN_DEBUG "ippp_ccp: no reset sent\n");
2422                 }
2423         } else {
2424                 /* The reset params are invalid. The decompressor does not
2425                    care about them, so we just send the minimal requests
2426                    and increase ids only when an Ack is received for a
2427                    given id */
2428                 if(is->reset->rs[is->reset->lastid]) {
2429                         /* There is already a transaction in existence
2430                            for this id. May be still waiting for a
2431                            Ack or may be wrong. */
2432                         rs = is->reset->rs[is->reset->lastid];
2433                         if(rs->state == CCPResetSentReq && rs->ta) {
2434                                 printk(KERN_DEBUG "ippp_ccp: reset"
2435                                        " trans still in progress"
2436                                        " for id %d\n", rp->id);
2437                         } else {
2438                                 printk(KERN_WARNING "ippp_ccp: reset"
2439                                        " trans in wrong state %d for"
2440                                        " id %d\n", rs->state, rp->id);
2441                         }
2442                 } else {
2443                         printk(KERN_DEBUG "ippp_ccp: new trans for id"
2444                                " %d to be started\n", is->reset->lastid);
2445                         rs = isdn_ppp_ccp_reset_alloc_state(is,
2446                                                             is->reset->lastid);
2447                         if(!rs) {
2448                                 printk(KERN_ERR "ippp_ccp: out of mem"
2449                                        " allocing ccp trans\n");
2450                                 return;
2451                         }
2452                         rs->state = CCPResetSentReq;
2453                         /* We always expect an Ack if the decompressor doesn't
2454                            know better */
2455                         rs->expra = 1;
2456                         rs->dlen = 0;
2457                         /* HACK TODO - add link comp here */
2458                         isdn_ppp_ccp_xmit_reset(is, PPP_CCP, CCP_RESETREQ,
2459                                                 rs->id, NULL, 0);
2460                         /* Start the timer */
2461                         rs->timer.expires = jiffies + 5*HZ;
2462                         add_timer(&rs->timer);
2463                         rs->ta = 1;
2464                 }
2465         }
2466 }
2467
2468 /* An Ack was received for this id. This means we stop the timer and clean
2469    up the state prior to calling the decompressors reset routine. */
2470 static void isdn_ppp_ccp_reset_ack_rcvd(struct ippp_struct *is,
2471                                         unsigned char id)
2472 {
2473         struct ippp_ccp_reset_state *rs = is->reset->rs[id];
2474
2475         if(rs) {
2476                 if(rs->ta && rs->state == CCPResetSentReq) {
2477                         /* Great, we are correct */
2478                         if(!rs->expra)
2479                                 printk(KERN_DEBUG "ippp_ccp: ResetAck received"
2480                                        " for id %d but not expected\n", id);
2481                 } else {
2482                         printk(KERN_INFO "ippp_ccp: ResetAck received out of"
2483                                "sync for id %d\n", id);
2484                 }
2485                 if(rs->ta) {
2486                         rs->ta = 0;
2487                         del_timer(&rs->timer);
2488                 }
2489                 isdn_ppp_ccp_reset_free_state(is, id);
2490         } else {
2491                 printk(KERN_INFO "ippp_ccp: ResetAck received for unknown id"
2492                        " %d\n", id);
2493         }
2494         /* Make sure the simple reset stuff uses a new id next time */
2495         is->reset->lastid++;
2496 }
2497
2498 /*
2499  * decompress packet
2500  *
2501  * if master = 0, we're trying to uncompress an per-link compressed packet,
2502  * as opposed to an compressed reconstructed-from-MPPP packet.
2503  * proto is updated to protocol field of uncompressed packet.
2504  *
2505  * retval: decompressed packet,
2506  *         same packet if uncompressed,
2507  *         NULL if decompression error
2508  */
2509
2510 static struct sk_buff *isdn_ppp_decompress(struct sk_buff *skb,struct ippp_struct *is,struct ippp_struct *master,
2511         int *proto)
2512 {
2513         void *stat = NULL;
2514         struct isdn_ppp_compressor *ipc = NULL;
2515         struct sk_buff *skb_out;
2516         int len;
2517         struct ippp_struct *ri;
2518         struct isdn_ppp_resetparams rsparm;
2519         unsigned char rsdata[IPPP_RESET_MAXDATABYTES];
2520
2521         if(!master) {
2522                 // per-link decompression
2523                 stat = is->link_decomp_stat;
2524                 ipc = is->link_decompressor;
2525                 ri = is;
2526         } else {
2527                 stat = master->decomp_stat;
2528                 ipc = master->decompressor;
2529                 ri = master;
2530         }
2531
2532         if (!ipc) {
2533                 // no decompressor -> we can't decompress.
2534                 printk(KERN_DEBUG "ippp: no decompressor defined!\n");
2535                 return skb;
2536         }
2537         if (!stat) // if we have a compressor, stat has been set as well
2538                 BUG();
2539
2540         if((master && *proto == PPP_COMP) || (!master && *proto == PPP_COMPFRAG) ) {
2541                 // compressed packets are compressed by their protocol type
2542
2543                 // Set up reset params for the decompressor
2544                 memset(&rsparm, 0, sizeof(rsparm));
2545                 rsparm.data = rsdata;
2546                 rsparm.maxdlen = IPPP_RESET_MAXDATABYTES;
2547
2548                 skb_out = dev_alloc_skb(is->mru + PPP_HDRLEN);
2549                 len = ipc->decompress(stat, skb, skb_out, &rsparm);
2550                 kfree_skb(skb);
2551                 if (len <= 0) {
2552                         switch(len) {
2553                         case DECOMP_ERROR:
2554                                 printk(KERN_INFO "ippp: decomp wants reset %s params\n",
2555                                        rsparm.valid ? "with" : "without");
2556
2557                                 isdn_ppp_ccp_reset_trans(ri, &rsparm);
2558                                 break;
2559                         case DECOMP_FATALERROR:
2560                                 ri->pppcfg |= SC_DC_FERROR;
2561                                 /* Kick ipppd to recognize the error */
2562                                 isdn_ppp_ccp_kickup(ri);
2563                                 break;
2564                         }
2565                         kfree_skb(skb_out);
2566                         return NULL;
2567                 }
2568                 *proto = isdn_ppp_strip_proto(skb_out);
2569                 if (*proto < 0) {
2570                         kfree_skb(skb_out);
2571                         return NULL;
2572                 }
2573                 return skb_out;
2574         } else {
2575                 // uncompressed packets are fed through the decompressor to
2576                 // update the decompressor state
2577                 ipc->incomp(stat, skb, *proto);
2578                 return skb;
2579         }
2580 }
2581
2582 /*
2583  * compress a frame
2584  *   type=0: normal/bundle compression
2585  *       =1: link compression
2586  * returns original skb if we haven't compressed the frame
2587  * and a new skb pointer if we've done it
2588  */
2589 static struct sk_buff *isdn_ppp_compress(struct sk_buff *skb_in,int *proto,
2590         struct ippp_struct *is,struct ippp_struct *master,int type)
2591 {
2592     int ret;
2593     int new_proto;
2594     struct isdn_ppp_compressor *compressor;
2595     void *stat;
2596     struct sk_buff *skb_out;
2597
2598         /* we do not compress control protocols */
2599     if(*proto < 0 || *proto > 0x3fff) {
2600             return skb_in;
2601     }
2602
2603         if(type) { /* type=1 => Link compression */
2604                 return skb_in;
2605         }
2606         else {
2607                 if(!master) {
2608                         compressor = is->compressor;
2609                         stat = is->comp_stat;
2610                 }
2611                 else {
2612                         compressor = master->compressor;
2613                         stat = master->comp_stat;
2614                 }
2615                 new_proto = PPP_COMP;
2616         }
2617
2618         if(!compressor) {
2619                 printk(KERN_ERR "isdn_ppp: No compressor set!\n");
2620                 return skb_in;
2621         }
2622         if(!stat) {
2623                 printk(KERN_ERR "isdn_ppp: Compressor not initialized?\n");
2624                 return skb_in;
2625         }
2626
2627         /* Allow for at least 150 % expansion (for now) */
2628         skb_out = alloc_skb(skb_in->len + skb_in->len/2 + 32 +
2629                 skb_headroom(skb_in), GFP_ATOMIC);
2630         if(!skb_out)
2631                 return skb_in;
2632         skb_reserve(skb_out, skb_headroom(skb_in));
2633
2634         ret = (compressor->compress)(stat,skb_in,skb_out,*proto);
2635         if(!ret) {
2636                 dev_kfree_skb(skb_out);
2637                 return skb_in;
2638         }
2639
2640         dev_kfree_skb(skb_in);
2641         *proto = new_proto;
2642         return skb_out;
2643 }
2644
2645 /*
2646  * we received a CCP frame ..
2647  * not a clean solution, but we MUST handle a few cases in the kernel
2648  */
2649 static void isdn_ppp_receive_ccp(isdn_net_dev *net_dev, isdn_net_local *lp,
2650          struct sk_buff *skb,int proto)
2651 {
2652         struct ippp_struct *is;
2653         struct ippp_struct *mis;
2654         int len;
2655         struct isdn_ppp_resetparams rsparm;
2656         unsigned char rsdata[IPPP_RESET_MAXDATABYTES];
2657
2658         printk(KERN_DEBUG "Received CCP frame from peer slot(%d)\n",
2659                 lp->ppp_slot);
2660         if (lp->ppp_slot < 0 || lp->ppp_slot > ISDN_MAX_CHANNELS) {
2661                 printk(KERN_ERR "%s: lp->ppp_slot(%d) out of range\n",
2662                         __FUNCTION__, lp->ppp_slot);
2663                 return;
2664         }
2665         is = ippp_table[lp->ppp_slot];
2666         isdn_ppp_frame_log("ccp-rcv", skb->data, skb->len, 32, is->unit,lp->ppp_slot);
2667
2668         if(lp->master) {
2669                 int slot = ((isdn_net_local *) (lp->master->priv))->ppp_slot;
2670                 if (slot < 0 || slot > ISDN_MAX_CHANNELS) {
2671                         printk(KERN_ERR "%s: slot(%d) out of range\n",
2672                                 __FUNCTION__, slot);
2673                         return;
2674                 }
2675                 mis = ippp_table[slot];
2676         } else
2677                 mis = is;
2678
2679         switch(skb->data[0]) {
2680         case CCP_CONFREQ:
2681                 if(is->debug & 0x10)
2682                         printk(KERN_DEBUG "Disable compression here!\n");
2683                 if(proto == PPP_CCP)
2684                         mis->compflags &= ~SC_COMP_ON;
2685                 else
2686                         is->compflags &= ~SC_LINK_COMP_ON;
2687                 break;
2688         case CCP_TERMREQ:
2689         case CCP_TERMACK:
2690                 if(is->debug & 0x10)
2691                         printk(KERN_DEBUG "Disable (de)compression here!\n");
2692                 if(proto == PPP_CCP)
2693                         mis->compflags &= ~(SC_DECOMP_ON|SC_COMP_ON);
2694                 else
2695                         is->compflags &= ~(SC_LINK_DECOMP_ON|SC_LINK_COMP_ON);
2696                 break;
2697         case CCP_CONFACK:
2698                 /* if we RECEIVE an ackowledge we enable the decompressor */
2699                 if(is->debug & 0x10)
2700                         printk(KERN_DEBUG "Enable decompression here!\n");
2701                 if(proto == PPP_CCP) {
2702                         if (!mis->decompressor)
2703                                 break;
2704                         mis->compflags |= SC_DECOMP_ON;
2705                 } else {
2706                         if (!is->decompressor)
2707                                 break;
2708                         is->compflags |= SC_LINK_DECOMP_ON;
2709                 }
2710                 break;
2711
2712         case CCP_RESETACK:
2713                 printk(KERN_DEBUG "Received ResetAck from peer\n");
2714                 len = (skb->data[2] << 8) | skb->data[3];
2715                 len -= 4;
2716
2717                 if(proto == PPP_CCP) {
2718                         /* If a reset Ack was outstanding for this id, then
2719                            clean up the state engine */
2720                         isdn_ppp_ccp_reset_ack_rcvd(mis, skb->data[1]);
2721                         if(mis->decompressor && mis->decomp_stat)
2722                                 mis->decompressor->
2723                                         reset(mis->decomp_stat,
2724                                               skb->data[0],
2725                                               skb->data[1],
2726                                               len ? &skb->data[4] : NULL,
2727                                               len, NULL);
2728                         /* TODO: This is not easy to decide here */
2729                         mis->compflags &= ~SC_DECOMP_DISCARD;
2730                 }
2731                 else {
2732                         isdn_ppp_ccp_reset_ack_rcvd(is, skb->data[1]);
2733                         if(is->link_decompressor && is->link_decomp_stat)
2734                                 is->link_decompressor->
2735                                         reset(is->link_decomp_stat,
2736                                               skb->data[0],
2737                                               skb->data[1],
2738                                               len ? &skb->data[4] : NULL,
2739                                               len, NULL);
2740                         /* TODO: neither here */
2741                         is->compflags &= ~SC_LINK_DECOMP_DISCARD;
2742                 }
2743                 break;
2744
2745         case CCP_RESETREQ:
2746                 printk(KERN_DEBUG "Received ResetReq from peer\n");
2747                 /* Receiving a ResetReq means we must reset our compressor */
2748                 /* Set up reset params for the reset entry */
2749                 memset(&rsparm, 0, sizeof(rsparm));
2750                 rsparm.data = rsdata;
2751                 rsparm.maxdlen = IPPP_RESET_MAXDATABYTES;
2752                 /* Isolate data length */
2753                 len = (skb->data[2] << 8) | skb->data[3];
2754                 len -= 4;
2755                 if(proto == PPP_CCP) {
2756                         if(mis->compressor && mis->comp_stat)
2757                                 mis->compressor->
2758                                         reset(mis->comp_stat,
2759                                               skb->data[0],
2760                                               skb->data[1],
2761                                               len ? &skb->data[4] : NULL,
2762                                               len, &rsparm);
2763                 }
2764                 else {
2765                         if(is->link_compressor && is->link_comp_stat)
2766                                 is->link_compressor->
2767                                         reset(is->link_comp_stat,
2768                                               skb->data[0],
2769                                               skb->data[1],
2770                                               len ? &skb->data[4] : NULL,
2771                                               len, &rsparm);
2772                 }
2773                 /* Ack the Req as specified by rsparm */
2774                 if(rsparm.valid) {
2775                         /* Compressor reset handler decided how to answer */
2776                         if(rsparm.rsend) {
2777                                 /* We should send a Frame */
2778                                 isdn_ppp_ccp_xmit_reset(is, proto, CCP_RESETACK,
2779                                                         rsparm.idval ? rsparm.id
2780                                                         : skb->data[1],
2781                                                         rsparm.dtval ?
2782                                                         rsparm.data : NULL,
2783                                                         rsparm.dtval ?
2784                                                         rsparm.dlen : 0);
2785                         } else {
2786                                 printk(KERN_DEBUG "ResetAck suppressed\n");
2787                         }
2788                 } else {
2789                         /* We answer with a straight reflected Ack */
2790                         isdn_ppp_ccp_xmit_reset(is, proto, CCP_RESETACK,
2791                                                 skb->data[1],
2792                                                 len ? &skb->data[4] : NULL,
2793                                                 len);
2794                 }
2795                 break;
2796         }
2797 }
2798
2799
2800 /*
2801  * Daemon sends a CCP frame ...
2802  */
2803
2804 /* TODO: Clean this up with new Reset semantics */
2805
2806 /* I believe the CCP handling as-is is done wrong. Compressed frames
2807  * should only be sent/received after CCP reaches UP state, which means
2808  * both sides have sent CONF_ACK. Currently, we handle both directions
2809  * independently, which means we may accept compressed frames too early
2810  * (supposedly not a problem), but may also mean we send compressed frames
2811  * too early, which may turn out to be a problem.
2812  * This part of state machine should actually be handled by (i)pppd, but
2813  * that's too big of a change now. --kai
2814  */
2815
2816 /* Actually, we might turn this into an advantage: deal with the RFC in
2817  * the old tradition of beeing generous on what we accept, but beeing
2818  * strict on what we send. Thus we should just
2819  * - accept compressed frames as soon as decompression is negotiated
2820  * - send compressed frames only when decomp *and* comp are negotiated
2821  * - drop rx compressed frames if we cannot decomp (instead of pushing them
2822  *   up to ipppd)
2823  * and I tried to modify this file according to that. --abp
2824  */
2825
2826 static void isdn_ppp_send_ccp(isdn_net_dev *net_dev, isdn_net_local *lp, struct sk_buff *skb)
2827 {
2828         struct ippp_struct *mis,*is;
2829         int proto, slot = lp->ppp_slot;
2830         unsigned char *data;
2831
2832         if(!skb || skb->len < 3)
2833                 return;
2834         if (slot < 0 || slot >= ISDN_MAX_CHANNELS) {
2835                 printk(KERN_ERR "%s: lp->ppp_slot(%d) out of range\n",
2836                         __FUNCTION__, slot);
2837                 return;
2838         }
2839         is = ippp_table[slot];
2840         /* Daemon may send with or without address and control field comp */
2841         data = skb->data;
2842         if(!(is->pppcfg & SC_COMP_AC) && data[0] == 0xff && data[1] == 0x03) {
2843                 data += 2;
2844                 if(skb->len < 5)
2845                         return;
2846         }
2847
2848         proto = ((int)data[0]<<8)+data[1];
2849         if(proto != PPP_CCP && proto != PPP_CCPFRAG)
2850                 return;
2851
2852         printk(KERN_DEBUG "Received CCP frame from daemon:\n");
2853         isdn_ppp_frame_log("ccp-xmit", skb->data, skb->len, 32, is->unit,lp->ppp_slot);
2854
2855         if (lp->master) {
2856                 slot = ((isdn_net_local *) (lp->master->priv))->ppp_slot;
2857                 if (slot < 0 || slot > ISDN_MAX_CHANNELS) {
2858                         printk(KERN_ERR "%s: slot(%d) out of range\n",
2859                                 __FUNCTION__, slot);
2860                         return;
2861                 }
2862                 mis = ippp_table[slot];
2863         } else
2864                 mis = is;
2865         if (mis != is)
2866                 printk(KERN_DEBUG "isdn_ppp: Ouch! Master CCP sends on slave slot!\n");
2867
2868         switch(data[2]) {
2869         case CCP_CONFREQ:
2870                 if(is->debug & 0x10)
2871                         printk(KERN_DEBUG "Disable decompression here!\n");
2872                 if(proto == PPP_CCP)
2873                         is->compflags &= ~SC_DECOMP_ON;
2874                 else
2875                         is->compflags &= ~SC_LINK_DECOMP_ON;
2876                 break;
2877         case CCP_TERMREQ:
2878         case CCP_TERMACK:
2879                 if(is->debug & 0x10)
2880                         printk(KERN_DEBUG "Disable (de)compression here!\n");
2881                 if(proto == PPP_CCP)
2882                         is->compflags &= ~(SC_DECOMP_ON|SC_COMP_ON);
2883                 else
2884                         is->compflags &= ~(SC_LINK_DECOMP_ON|SC_LINK_COMP_ON);
2885                 break;
2886         case CCP_CONFACK:
2887                 /* if we SEND an ackowledge we can/must enable the compressor */
2888                 if(is->debug & 0x10)
2889                         printk(KERN_DEBUG "Enable compression here!\n");
2890                 if(proto == PPP_CCP) {
2891                         if (!is->compressor)
2892                                 break;
2893                         is->compflags |= SC_COMP_ON;
2894                 } else {
2895                         if (!is->compressor)
2896                                 break;
2897                         is->compflags |= SC_LINK_COMP_ON;
2898                 }
2899                 break;
2900         case CCP_RESETACK:
2901                 /* If we send a ACK we should reset our compressor */
2902                 if(is->debug & 0x10)
2903                         printk(KERN_DEBUG "Reset decompression state here!\n");
2904                 printk(KERN_DEBUG "ResetAck from daemon passed by\n");
2905                 if(proto == PPP_CCP) {
2906                         /* link to master? */
2907                         if(is->compressor && is->comp_stat)
2908                                 is->compressor->reset(is->comp_stat, 0, 0,
2909                                                       NULL, 0, NULL);
2910                         is->compflags &= ~SC_COMP_DISCARD;
2911                 }
2912                 else {
2913                         if(is->link_compressor && is->link_comp_stat)
2914                                 is->link_compressor->reset(is->link_comp_stat,
2915                                                            0, 0, NULL, 0, NULL);
2916                         is->compflags &= ~SC_LINK_COMP_DISCARD;
2917                 }
2918                 break;
2919         case CCP_RESETREQ:
2920                 /* Just let it pass by */
2921                 printk(KERN_DEBUG "ResetReq from daemon passed by\n");
2922                 break;
2923         }
2924 }
2925
2926 int isdn_ppp_register_compressor(struct isdn_ppp_compressor *ipc)
2927 {
2928         ipc->next = ipc_head;
2929         ipc->prev = NULL;
2930         if(ipc_head) {
2931                 ipc_head->prev = ipc;
2932         }
2933         ipc_head = ipc;
2934         return 0;
2935 }
2936
2937 int isdn_ppp_unregister_compressor(struct isdn_ppp_compressor *ipc)
2938 {
2939         if(ipc->prev)
2940                 ipc->prev->next = ipc->next;
2941         else
2942                 ipc_head = ipc->next;
2943         if(ipc->next)
2944                 ipc->next->prev = ipc->prev;
2945         ipc->prev = ipc->next = NULL;
2946         return 0;
2947 }
2948
2949 static int isdn_ppp_set_compressor(struct ippp_struct *is, struct isdn_ppp_comp_data *data)
2950 {
2951         struct isdn_ppp_compressor *ipc = ipc_head;
2952         int ret;
2953         void *stat;
2954         int num = data->num;
2955
2956         if(is->debug & 0x10)
2957                 printk(KERN_DEBUG "[%d] Set %s type %d\n",is->unit,
2958                         (data->flags&IPPP_COMP_FLAG_XMIT)?"compressor":"decompressor",num);
2959
2960         /* If is has no valid reset state vector, we cannot allocate a
2961            decompressor. The decompressor would cause reset transactions
2962            sooner or later, and they need that vector. */
2963
2964         if(!(data->flags & IPPP_COMP_FLAG_XMIT) && !is->reset) {
2965                 printk(KERN_ERR "ippp_ccp: no reset data structure - can't"
2966                        " allow decompression.\n");
2967                 return -ENOMEM;
2968         }
2969
2970         while(ipc) {
2971                 if(ipc->num == num) {
2972                         stat = ipc->alloc(data);
2973                         if(stat) {
2974                                 ret = ipc->init(stat,data,is->unit,0);
2975                                 if(!ret) {
2976                                         printk(KERN_ERR "Can't init (de)compression!\n");
2977                                         ipc->free(stat);
2978                                         stat = NULL;
2979                                         break;
2980                                 }
2981                         }
2982                         else {
2983                                 printk(KERN_ERR "Can't alloc (de)compression!\n");
2984                                 break;
2985                         }
2986
2987                         if(data->flags & IPPP_COMP_FLAG_XMIT) {
2988                                 if(data->flags & IPPP_COMP_FLAG_LINK) {
2989                                         if(is->link_comp_stat)
2990                                                 is->link_compressor->free(is->link_comp_stat);
2991                                         is->link_comp_stat = stat;
2992                                         is->link_compressor = ipc;
2993                                 }
2994                                 else {
2995                                         if(is->comp_stat)
2996                                                 is->compressor->free(is->comp_stat);
2997                                         is->comp_stat = stat;
2998                                         is->compressor = ipc;
2999                                 }
3000                         }
3001                         else {
3002                                 if(data->flags & IPPP_COMP_FLAG_LINK) {
3003                                         if(is->link_decomp_stat)
3004                                                 is->link_decompressor->free(is->link_decomp_stat);
3005                                         is->link_decomp_stat = stat;
3006                                         is->link_decompressor = ipc;
3007                                 }
3008                                 else {
3009                                         if(is->decomp_stat)
3010                                                 is->decompressor->free(is->decomp_stat);
3011                                         is->decomp_stat = stat;
3012                                         is->decompressor = ipc;
3013                                 }
3014                         }
3015                         return 0;
3016                 }
3017                 ipc = ipc->next;
3018         }
3019         return -EINVAL;
3020 }