ccp.c revision 68906 
1/*
2 *	   PPP Compression Control Protocol (CCP) Module
3 *
4 *	    Written by Toshiharu OHNO (tony-o@iij.ad.jp)
5 *
6 *   Copyright (C) 1994, Internet Initiative Japan, Inc. All rights reserverd.
7 *
8 * Redistribution and use in source and binary forms are permitted
9 * provided that the above copyright notice and this paragraph are
10 * duplicated in all such forms and that any documentation,
11 * advertising materials, and other materials related to such
12 * distribution and use acknowledge that the software was developed
13 * by the Internet Initiative Japan, Inc.  The name of the
14 * IIJ may not be used to endorse or promote products derived
15 * from this software without specific prior written permission.
16 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
18 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
19 *
20 * $FreeBSD: head/usr.sbin/ppp/ccp.c 68906 2000-11-19 16:53:50Z brian $
21 *
22 *	TODO:
23 *		o Support other compression protocols
24 */
25#include <sys/param.h>
26#include <netinet/in.h>
27#include <netinet/in_systm.h>
28#include <netinet/ip.h>
29#include <sys/un.h>
30
31#include <stdio.h>
32#include <stdlib.h>
33#include <string.h>	/* memcpy() on some archs */
34#include <termios.h>
35
36#include "layer.h"
37#include "defs.h"
38#include "command.h"
39#include "mbuf.h"
40#include "log.h"
41#include "timer.h"
42#include "fsm.h"
43#include "proto.h"
44#include "pred.h"
45#include "deflate.h"
46#include "throughput.h"
47#include "iplist.h"
48#include "slcompress.h"
49#include "lqr.h"
50#include "hdlc.h"
51#include "lcp.h"
52#include "ccp.h"
53#include "ipcp.h"
54#include "filter.h"
55#include "descriptor.h"
56#include "prompt.h"
57#include "link.h"
58#include "mp.h"
59#include "async.h"
60#include "physical.h"
61#ifndef NORADIUS
62#include "radius.h"
63#endif
64#ifdef HAVE_DES
65#include "mppe.h"
66#endif
67#include "bundle.h"
68
69static void CcpSendConfigReq(struct fsm *);
70static void CcpSentTerminateReq(struct fsm *);
71static void CcpSendTerminateAck(struct fsm *, u_char);
72static void CcpDecodeConfig(struct fsm *, u_char *, int, int,
73                            struct fsm_decode *);
74static void CcpLayerStart(struct fsm *);
75static void CcpLayerFinish(struct fsm *);
76static int CcpLayerUp(struct fsm *);
77static void CcpLayerDown(struct fsm *);
78static void CcpInitRestartCounter(struct fsm *, int);
79static void CcpRecvResetReq(struct fsm *);
80static void CcpRecvResetAck(struct fsm *, u_char);
81
82static struct fsm_callbacks ccp_Callbacks = {
83  CcpLayerUp,
84  CcpLayerDown,
85  CcpLayerStart,
86  CcpLayerFinish,
87  CcpInitRestartCounter,
88  CcpSendConfigReq,
89  CcpSentTerminateReq,
90  CcpSendTerminateAck,
91  CcpDecodeConfig,
92  CcpRecvResetReq,
93  CcpRecvResetAck
94};
95
96static const char * const ccp_TimerNames[] =
97  {"CCP restart", "CCP openmode", "CCP stopped"};
98
99static const char *
100protoname(int proto)
101{
102  static char const * const cftypes[] = {
103    /* Check out the latest ``Compression Control Protocol'' rfc (1962) */
104    "OUI",		/* 0: OUI */
105    "PRED1",		/* 1: Predictor type 1 */
106    "PRED2",		/* 2: Predictor type 2 */
107    "PUDDLE",		/* 3: Puddle Jumber */
108    NULL, NULL, NULL, NULL, NULL, NULL,
109    NULL, NULL, NULL, NULL, NULL, NULL,
110    "HWPPC",		/* 16: Hewlett-Packard PPC */
111    "STAC",		/* 17: Stac Electronics LZS (rfc1974) */
112    "MPPE",		/* 18: Microsoft PPC (rfc2118) and */
113			/*     Microsoft PPE (draft-ietf-pppext-mppe) */
114    "GAND",		/* 19: Gandalf FZA (rfc1993) */
115    "V42BIS",		/* 20: ARG->DATA.42bis compression */
116    "BSD",		/* 21: BSD LZW Compress */
117    NULL,
118    "LZS-DCP",		/* 23: LZS-DCP Compression Protocol (rfc1967) */
119    "MAGNALINK/DEFLATE",/* 24: Magnalink Variable Resource (rfc1975) */
120			/* 24: Deflate (according to pppd-2.3.*) */
121    "DCE",		/* 25: Data Circuit-Terminating Equip (rfc1976) */
122    "DEFLATE",		/* 26: Deflate (rfc1979) */
123  };
124
125  if (proto < 0 || proto > sizeof cftypes / sizeof *cftypes ||
126      cftypes[proto] == NULL)
127    return HexStr(proto, NULL, 0);
128
129  return cftypes[proto];
130}
131
132/* We support these algorithms, and Req them in the given order */
133static const struct ccp_algorithm * const algorithm[] = {
134  &DeflateAlgorithm,
135  &Pred1Algorithm,
136  &PppdDeflateAlgorithm
137#ifdef HAVE_DES
138  , &MPPEAlgorithm
139#endif
140};
141
142#define NALGORITHMS (sizeof algorithm/sizeof algorithm[0])
143
144int
145ccp_ReportStatus(struct cmdargs const *arg)
146{
147  struct link *l;
148  struct ccp *ccp;
149
150  l = command_ChooseLink(arg);
151  ccp = &l->ccp;
152
153  prompt_Printf(arg->prompt, "%s: %s [%s]\n", l->name, ccp->fsm.name,
154                State2Nam(ccp->fsm.state));
155  if (ccp->fsm.state == ST_OPENED) {
156    prompt_Printf(arg->prompt, " My protocol = %s, His protocol = %s\n",
157                  protoname(ccp->my_proto), protoname(ccp->his_proto));
158    prompt_Printf(arg->prompt, " Output: %ld --> %ld,  Input: %ld --> %ld\n",
159                  ccp->uncompout, ccp->compout,
160                  ccp->compin, ccp->uncompin);
161  }
162
163  prompt_Printf(arg->prompt, "\n Defaults: ");
164  prompt_Printf(arg->prompt, "FSM retry = %us, max %u Config"
165                " REQ%s, %u Term REQ%s\n", ccp->cfg.fsm.timeout,
166                ccp->cfg.fsm.maxreq, ccp->cfg.fsm.maxreq == 1 ? "" : "s",
167                ccp->cfg.fsm.maxtrm, ccp->cfg.fsm.maxtrm == 1 ? "" : "s");
168  prompt_Printf(arg->prompt, "           deflate windows: ");
169  prompt_Printf(arg->prompt, "incoming = %d, ", ccp->cfg.deflate.in.winsize);
170  prompt_Printf(arg->prompt, "outgoing = %d\n", ccp->cfg.deflate.out.winsize);
171  prompt_Printf(arg->prompt, "           DEFLATE:    %s\n",
172                command_ShowNegval(ccp->cfg.neg[CCP_NEG_DEFLATE]));
173  prompt_Printf(arg->prompt, "           PREDICTOR1: %s\n",
174                command_ShowNegval(ccp->cfg.neg[CCP_NEG_PRED1]));
175  prompt_Printf(arg->prompt, "           DEFLATE24:  %s\n",
176                command_ShowNegval(ccp->cfg.neg[CCP_NEG_DEFLATE24]));
177#ifdef HAVE_DES
178  prompt_Printf(arg->prompt, "           MPPE:       %s",
179                command_ShowNegval(ccp->cfg.neg[CCP_NEG_MPPE]));
180  prompt_Printf(arg->prompt, " (Key Size = %d-bits)\n", ccp->cfg.mppe.keybits);
181#endif
182  return 0;
183}
184
185void
186ccp_SetupCallbacks(struct ccp *ccp)
187{
188  ccp->fsm.fn = &ccp_Callbacks;
189  ccp->fsm.FsmTimer.name = ccp_TimerNames[0];
190  ccp->fsm.OpenTimer.name = ccp_TimerNames[1];
191  ccp->fsm.StoppedTimer.name = ccp_TimerNames[2];
192}
193
194void
195ccp_Init(struct ccp *ccp, struct bundle *bundle, struct link *l,
196         const struct fsm_parent *parent)
197{
198  /* Initialise ourselves */
199
200  fsm_Init(&ccp->fsm, "CCP", PROTO_CCP, 1, CCP_MAXCODE, LogCCP,
201           bundle, l, parent, &ccp_Callbacks, ccp_TimerNames);
202
203  ccp->cfg.deflate.in.winsize = 0;
204  ccp->cfg.deflate.out.winsize = 15;
205  ccp->cfg.fsm.timeout = DEF_FSMRETRY;
206  ccp->cfg.fsm.maxreq = DEF_FSMTRIES;
207  ccp->cfg.fsm.maxtrm = DEF_FSMTRIES;
208  ccp->cfg.neg[CCP_NEG_DEFLATE] = NEG_ENABLED|NEG_ACCEPTED;
209  ccp->cfg.neg[CCP_NEG_PRED1] = NEG_ENABLED|NEG_ACCEPTED;
210  ccp->cfg.neg[CCP_NEG_DEFLATE24] = 0;
211#ifdef HAVE_DES
212  ccp->cfg.mppe.keybits = 128;
213  ccp->cfg.neg[CCP_NEG_MPPE] = NEG_ENABLED|NEG_ACCEPTED;
214#endif
215
216  ccp_Setup(ccp);
217}
218
219void
220ccp_Setup(struct ccp *ccp)
221{
222  /* Set ourselves up for a startup */
223  ccp->fsm.open_mode = 0;
224  ccp->his_proto = ccp->my_proto = -1;
225  ccp->reset_sent = ccp->last_reset = -1;
226  ccp->in.algorithm = ccp->out.algorithm = -1;
227  ccp->in.state = ccp->out.state = NULL;
228  ccp->in.opt.id = -1;
229  ccp->out.opt = NULL;
230  ccp->his_reject = ccp->my_reject = 0;
231  ccp->uncompout = ccp->compout = 0;
232  ccp->uncompin = ccp->compin = 0;
233}
234
235static void
236CcpInitRestartCounter(struct fsm *fp, int what)
237{
238  /* Set fsm timer load */
239  struct ccp *ccp = fsm2ccp(fp);
240
241  fp->FsmTimer.load = ccp->cfg.fsm.timeout * SECTICKS;
242  switch (what) {
243    case FSM_REQ_TIMER:
244      fp->restart = ccp->cfg.fsm.maxreq;
245      break;
246    case FSM_TRM_TIMER:
247      fp->restart = ccp->cfg.fsm.maxtrm;
248      break;
249    default:
250      fp->restart = 1;
251      break;
252  }
253}
254
255static void
256CcpSendConfigReq(struct fsm *fp)
257{
258  /* Send config REQ please */
259  struct ccp *ccp = fsm2ccp(fp);
260  struct ccp_opt **o;
261  u_char *cp, buff[100];
262  int f, alloc;
263
264  cp = buff;
265  o = &ccp->out.opt;
266  alloc = ccp->his_reject == 0 && ccp->out.opt == NULL;
267  ccp->my_proto = -1;
268  ccp->out.algorithm = -1;
269  for (f = 0; f < NALGORITHMS; f++)
270    if (IsEnabled(ccp->cfg.neg[algorithm[f]->Neg]) &&
271        !REJECTED(ccp, algorithm[f]->id)) {
272
273      if (!alloc)
274        for (o = &ccp->out.opt; *o != NULL; o = &(*o)->next)
275          if ((*o)->val.id == algorithm[f]->id && (*o)->algorithm == f)
276            break;
277
278      if (alloc || *o == NULL) {
279        *o = (struct ccp_opt *)malloc(sizeof(struct ccp_opt));
280        (*o)->val.id = algorithm[f]->id;
281        (*o)->val.len = 2;
282        (*o)->next = NULL;
283        (*o)->algorithm = f;
284        (*algorithm[f]->o.OptInit)(&(*o)->val, &ccp->cfg);
285      }
286
287      if (cp + (*o)->val.len > buff + sizeof buff) {
288        log_Printf(LogERROR, "%s: CCP REQ buffer overrun !\n", fp->link->name);
289        break;
290      }
291      memcpy(cp, &(*o)->val, (*o)->val.len);
292      cp += (*o)->val.len;
293
294      ccp->my_proto = (*o)->val.id;
295      ccp->out.algorithm = f;
296
297      if (alloc)
298        o = &(*o)->next;
299    }
300
301  fsm_Output(fp, CODE_CONFIGREQ, fp->reqid, buff, cp - buff, MB_CCPOUT);
302}
303
304void
305ccp_SendResetReq(struct fsm *fp)
306{
307  /* We can't read our input - ask peer to reset */
308  struct ccp *ccp = fsm2ccp(fp);
309
310  ccp->reset_sent = fp->reqid;
311  ccp->last_reset = -1;
312  fsm_Output(fp, CODE_RESETREQ, fp->reqid, NULL, 0, MB_CCPOUT);
313}
314
315static void
316CcpSentTerminateReq(struct fsm *fp)
317{
318  /* Term REQ just sent by FSM */
319}
320
321static void
322CcpSendTerminateAck(struct fsm *fp, u_char id)
323{
324  /* Send Term ACK please */
325  fsm_Output(fp, CODE_TERMACK, id, NULL, 0, MB_CCPOUT);
326}
327
328static void
329CcpRecvResetReq(struct fsm *fp)
330{
331  /* Got a reset REQ, reset outgoing dictionary */
332  struct ccp *ccp = fsm2ccp(fp);
333  if (ccp->out.state != NULL)
334    (*algorithm[ccp->out.algorithm]->o.Reset)(ccp->out.state);
335}
336
337static void
338CcpLayerStart(struct fsm *fp)
339{
340  /* We're about to start up ! */
341  struct ccp *ccp = fsm2ccp(fp);
342
343  log_Printf(LogCCP, "%s: LayerStart.\n", fp->link->name);
344  fp->more.reqs = fp->more.naks = fp->more.rejs = ccp->cfg.fsm.maxreq * 3;
345}
346
347static void
348CcpLayerDown(struct fsm *fp)
349{
350  /* About to come down */
351  struct ccp *ccp = fsm2ccp(fp);
352  struct ccp_opt *next;
353
354  log_Printf(LogCCP, "%s: LayerDown.\n", fp->link->name);
355  if (ccp->in.state != NULL) {
356    (*algorithm[ccp->in.algorithm]->i.Term)(ccp->in.state);
357    ccp->in.state = NULL;
358    ccp->in.algorithm = -1;
359  }
360  if (ccp->out.state != NULL) {
361    (*algorithm[ccp->out.algorithm]->o.Term)(ccp->out.state);
362    ccp->out.state = NULL;
363    ccp->out.algorithm = -1;
364  }
365  ccp->his_reject = ccp->my_reject = 0;
366
367  while (ccp->out.opt) {
368    next = ccp->out.opt->next;
369    free(ccp->out.opt);
370    ccp->out.opt = next;
371  }
372  ccp_Setup(ccp);
373}
374
375static void
376CcpLayerFinish(struct fsm *fp)
377{
378  /* We're now down */
379  struct ccp *ccp = fsm2ccp(fp);
380  struct ccp_opt *next;
381
382  log_Printf(LogCCP, "%s: LayerFinish.\n", fp->link->name);
383
384  /*
385   * Nuke options that may be left over from sending a REQ but never
386   * coming up.
387   */
388  while (ccp->out.opt) {
389    next = ccp->out.opt->next;
390    free(ccp->out.opt);
391    ccp->out.opt = next;
392  }
393}
394
395/*  Called when CCP has reached the OPEN state */
396static int
397CcpLayerUp(struct fsm *fp)
398{
399  /* We're now up */
400  struct ccp *ccp = fsm2ccp(fp);
401  struct ccp_opt **o;
402  int f;
403
404  log_Printf(LogCCP, "%s: LayerUp.\n", fp->link->name);
405
406  if (ccp->in.state == NULL && ccp->in.algorithm >= 0 &&
407      ccp->in.algorithm < NALGORITHMS) {
408    ccp->in.state = (*algorithm[ccp->in.algorithm]->i.Init)(&ccp->in.opt);
409    if (ccp->in.state == NULL) {
410      log_Printf(LogERROR, "%s: %s (in) initialisation failure\n",
411                fp->link->name, protoname(ccp->his_proto));
412      ccp->his_proto = ccp->my_proto = -1;
413      fsm_Close(fp);
414      return 0;
415    }
416  }
417
418  o = &ccp->out.opt;
419  for (f = 0; f < ccp->out.algorithm; f++)
420    if (IsEnabled(ccp->cfg.neg[algorithm[f]->Neg]))
421      o = &(*o)->next;
422
423  if (ccp->out.state == NULL && ccp->out.algorithm >= 0 &&
424      ccp->out.algorithm < NALGORITHMS) {
425    ccp->out.state = (*algorithm[ccp->out.algorithm]->o.Init)(&(*o)->val);
426    if (ccp->out.state == NULL) {
427      log_Printf(LogERROR, "%s: %s (out) initialisation failure\n",
428                fp->link->name, protoname(ccp->my_proto));
429      ccp->his_proto = ccp->my_proto = -1;
430      fsm_Close(fp);
431      return 0;
432    }
433  }
434
435  fp->more.reqs = fp->more.naks = fp->more.rejs = ccp->cfg.fsm.maxreq * 3;
436
437  log_Printf(LogCCP, "%s: Out = %s[%d], In = %s[%d]\n",
438            fp->link->name, protoname(ccp->my_proto), ccp->my_proto,
439            protoname(ccp->his_proto), ccp->his_proto);
440
441  return 1;
442}
443
444static void
445CcpDecodeConfig(struct fsm *fp, u_char *cp, int plen, int mode_type,
446                struct fsm_decode *dec)
447{
448  /* Deal with incoming data */
449  struct ccp *ccp = fsm2ccp(fp);
450  int type, length, f;
451  const char *end;
452
453  if (mode_type == MODE_REQ)
454    ccp->in.algorithm = -1;	/* In case we've received two REQs in a row */
455
456  while (plen >= sizeof(struct fsmconfig)) {
457    type = *cp;
458    length = cp[1];
459
460    if (length == 0) {
461      log_Printf(LogCCP, "%s: CCP size zero\n", fp->link->name);
462      break;
463    }
464
465    if (length > sizeof(struct lcp_opt)) {
466      length = sizeof(struct lcp_opt);
467      log_Printf(LogCCP, "%s: Warning: Truncating length to %d\n",
468                fp->link->name, length);
469    }
470
471    for (f = NALGORITHMS-1; f > -1; f--)
472      if (algorithm[f]->id == type)
473        break;
474
475    end = f == -1 ? "" : (*algorithm[f]->Disp)((struct lcp_opt *)cp);
476    if (end == NULL)
477      end = "";
478
479    log_Printf(LogCCP, " %s[%d] %s\n", protoname(type), length, end);
480
481    if (f == -1) {
482      /* Don't understand that :-( */
483      if (mode_type == MODE_REQ) {
484        ccp->my_reject |= (1 << type);
485        memcpy(dec->rejend, cp, length);
486        dec->rejend += length;
487      }
488    } else {
489      struct ccp_opt *o;
490
491      switch (mode_type) {
492      case MODE_REQ:
493	if (IsAccepted(ccp->cfg.neg[algorithm[f]->Neg]) &&
494            ccp->in.algorithm == -1) {
495	  memcpy(&ccp->in.opt, cp, length);
496          switch ((*algorithm[f]->i.Set)(&ccp->in.opt, &ccp->cfg)) {
497          case MODE_REJ:
498	    memcpy(dec->rejend, &ccp->in.opt, ccp->in.opt.len);
499	    dec->rejend += ccp->in.opt.len;
500            break;
501          case MODE_NAK:
502	    memcpy(dec->nakend, &ccp->in.opt, ccp->in.opt.len);
503	    dec->nakend += ccp->in.opt.len;
504            break;
505          case MODE_ACK:
506	    memcpy(dec->ackend, cp, length);
507	    dec->ackend += length;
508	    ccp->his_proto = type;
509            ccp->in.algorithm = f;		/* This one'll do :-) */
510            break;
511          }
512	} else {
513	  memcpy(dec->rejend, cp, length);
514	  dec->rejend += length;
515	}
516	break;
517      case MODE_NAK:
518        for (o = ccp->out.opt; o != NULL; o = o->next)
519          if (o->val.id == cp[0])
520            break;
521        if (o == NULL)
522          log_Printf(LogCCP, "%s: Warning: Ignoring peer NAK of unsent"
523                     " option\n", fp->link->name);
524        else {
525	  memcpy(&o->val, cp, length);
526          if ((*algorithm[f]->o.Set)(&o->val) == MODE_ACK)
527            ccp->my_proto = algorithm[f]->id;
528          else {
529	    ccp->his_reject |= (1 << type);
530	    ccp->my_proto = -1;
531          }
532        }
533        break;
534      case MODE_REJ:
535	ccp->his_reject |= (1 << type);
536	ccp->my_proto = -1;
537	break;
538      }
539    }
540
541    plen -= cp[1];
542    cp += cp[1];
543  }
544
545  if (mode_type != MODE_NOP) {
546    if (dec->rejend != dec->rej) {
547      /* rejects are preferred */
548      dec->ackend = dec->ack;
549      dec->nakend = dec->nak;
550      if (ccp->in.state == NULL) {
551        ccp->his_proto = -1;
552        ccp->in.algorithm = -1;
553      }
554    } else if (dec->nakend != dec->nak) {
555      /* then NAKs */
556      dec->ackend = dec->ack;
557      if (ccp->in.state == NULL) {
558        ccp->his_proto = -1;
559        ccp->in.algorithm = -1;
560      }
561    }
562  }
563}
564
565extern struct mbuf *
566ccp_Input(struct bundle *bundle, struct link *l, struct mbuf *bp)
567{
568  /* Got PROTO_CCP from link */
569  m_settype(bp, MB_CCPIN);
570  if (bundle_Phase(bundle) == PHASE_NETWORK)
571    fsm_Input(&l->ccp.fsm, bp);
572  else {
573    if (bundle_Phase(bundle) < PHASE_NETWORK)
574      log_Printf(LogCCP, "%s: Error: Unexpected CCP in phase %s (ignored)\n",
575                 l->ccp.fsm.link->name, bundle_PhaseName(bundle));
576    m_freem(bp);
577  }
578  return NULL;
579}
580
581static void
582CcpRecvResetAck(struct fsm *fp, u_char id)
583{
584  /* Got a reset ACK, reset incoming dictionary */
585  struct ccp *ccp = fsm2ccp(fp);
586
587  if (ccp->reset_sent != -1) {
588    if (id != ccp->reset_sent) {
589      log_Printf(LogCCP, "%s: Incorrect ResetAck (id %d, not %d)"
590                " ignored\n", fp->link->name, id, ccp->reset_sent);
591      return;
592    }
593    /* Whaddaya know - a correct reset ack */
594  } else if (id == ccp->last_reset)
595    log_Printf(LogCCP, "%s: Duplicate ResetAck (resetting again)\n",
596               fp->link->name);
597  else {
598    log_Printf(LogCCP, "%s: Unexpected ResetAck (id %d) ignored\n",
599               fp->link->name, id);
600    return;
601  }
602
603  ccp->last_reset = ccp->reset_sent;
604  ccp->reset_sent = -1;
605  if (ccp->in.state != NULL)
606    (*algorithm[ccp->in.algorithm]->i.Reset)(ccp->in.state);
607}
608
609static struct mbuf *
610ccp_LayerPush(struct bundle *b, struct link *l, struct mbuf *bp,
611              int pri, u_short *proto)
612{
613  if (PROTO_COMPRESSIBLE(*proto) && l->ccp.fsm.state == ST_OPENED &&
614      l->ccp.out.state != NULL) {
615    bp = (*algorithm[l->ccp.out.algorithm]->o.Write)
616           (l->ccp.out.state, &l->ccp, l, pri, proto, bp);
617    switch (*proto) {
618      case PROTO_ICOMPD:
619        m_settype(bp, MB_ICOMPDOUT);
620        break;
621      case PROTO_COMPD:
622        m_settype(bp, MB_COMPDOUT);
623        break;
624    }
625  }
626
627  return bp;
628}
629
630static struct mbuf *
631ccp_LayerPull(struct bundle *b, struct link *l, struct mbuf *bp, u_short *proto)
632{
633  /*
634   * If proto isn't PROTO_[I]COMPD, we still want to pass it to the
635   * decompression routines so that the dictionary's updated
636   */
637  if (l->ccp.fsm.state == ST_OPENED) {
638    if (*proto == PROTO_COMPD || *proto == PROTO_ICOMPD) {
639      log_Printf(LogDEBUG, "ccp_LayerPull: PROTO_%sCOMPDP -> PROTO_IP\n",
640                 *proto == PROTO_ICOMPD ? "I" : "");
641      /* Decompress incoming data */
642      if (l->ccp.reset_sent != -1)
643        /* Send another REQ and put the packet in the bit bucket */
644        fsm_Output(&l->ccp.fsm, CODE_RESETREQ, l->ccp.reset_sent, NULL, 0,
645                   MB_CCPOUT);
646      else if (l->ccp.in.state != NULL) {
647        bp = (*algorithm[l->ccp.in.algorithm]->i.Read)
648               (l->ccp.in.state, &l->ccp, proto, bp);
649        switch (*proto) {
650          case PROTO_ICOMPD:
651            m_settype(bp, MB_ICOMPDIN);
652            break;
653          case PROTO_COMPD:
654            m_settype(bp, MB_COMPDIN);
655            break;
656        }
657        return bp;
658      }
659      m_freem(bp);
660      bp = NULL;
661    } else if (PROTO_COMPRESSIBLE(*proto) && l->ccp.in.state != NULL) {
662      log_Printf(LogDEBUG, "ccp_LayerPull: Ignore packet (dict only)\n");
663      /* Add incoming Network Layer traffic to our dictionary */
664      (*algorithm[l->ccp.in.algorithm]->i.DictSetup)
665        (l->ccp.in.state, &l->ccp, *proto, bp);
666    } else
667      log_Printf(LogDEBUG, "ccp_LayerPull: Ignore packet\n");
668  }
669
670  return bp;
671}
672
673u_short
674ccp_Proto(struct ccp *ccp)
675{
676  return !link2physical(ccp->fsm.link) || !ccp->fsm.bundle->ncp.mp.active ?
677         PROTO_COMPD : PROTO_ICOMPD;
678}
679
680int
681ccp_SetOpenMode(struct ccp *ccp)
682{
683  int f;
684
685  for (f = 0; f < CCP_NEG_TOTAL; f++)
686    if (IsEnabled(ccp->cfg.neg[f])) {
687      ccp->fsm.open_mode = 0;
688      return 1;
689    }
690
691  ccp->fsm.open_mode = OPEN_PASSIVE;	/* Go straight to ST_STOPPED ? */
692
693  for (f = 0; f < CCP_NEG_TOTAL; f++)
694    if (IsAccepted(ccp->cfg.neg[f]))
695      return 1;
696
697  return 0;				/* No CCP at all */
698}
699
700struct layer ccplayer = { LAYER_CCP, "ccp", ccp_LayerPush, ccp_LayerPull };
701