ccp.c revision 78411 
1/*-
2 * Copyright (c) 1996 - 2001 Brian Somers <brian@Awfulhak.org>
3 *          based on work by Toshiharu OHNO <tony-o@iij.ad.jp>
4 *                           Internet Initiative Japan, Inc (IIJ)
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 *
28 * $FreeBSD: head/usr.sbin/ppp/ccp.c 78411 2001-06-18 15:00:22Z brian $
29 */
30
31#include <sys/param.h>
32#include <netinet/in.h>
33#include <netinet/in_systm.h>
34#include <netinet/ip.h>
35#include <sys/un.h>
36
37#include <stdio.h>
38#include <stdlib.h>
39#include <string.h>	/* memcpy() on some archs */
40#include <termios.h>
41
42#include "layer.h"
43#include "defs.h"
44#include "command.h"
45#include "mbuf.h"
46#include "log.h"
47#include "timer.h"
48#include "fsm.h"
49#include "proto.h"
50#include "pred.h"
51#include "deflate.h"
52#include "throughput.h"
53#include "iplist.h"
54#include "slcompress.h"
55#include "lqr.h"
56#include "hdlc.h"
57#include "lcp.h"
58#include "ccp.h"
59#include "ipcp.h"
60#include "filter.h"
61#include "descriptor.h"
62#include "prompt.h"
63#include "link.h"
64#include "mp.h"
65#include "async.h"
66#include "physical.h"
67#ifndef NORADIUS
68#include "radius.h"
69#endif
70#ifdef HAVE_DES
71#include "mppe.h"
72#endif
73#include "bundle.h"
74
75static void CcpSendConfigReq(struct fsm *);
76static void CcpSentTerminateReq(struct fsm *);
77static void CcpSendTerminateAck(struct fsm *, u_char);
78static void CcpDecodeConfig(struct fsm *, u_char *, int, int,
79                            struct fsm_decode *);
80static void CcpLayerStart(struct fsm *);
81static void CcpLayerFinish(struct fsm *);
82static int CcpLayerUp(struct fsm *);
83static void CcpLayerDown(struct fsm *);
84static void CcpInitRestartCounter(struct fsm *, int);
85static int CcpRecvResetReq(struct fsm *);
86static void CcpRecvResetAck(struct fsm *, u_char);
87
88static struct fsm_callbacks ccp_Callbacks = {
89  CcpLayerUp,
90  CcpLayerDown,
91  CcpLayerStart,
92  CcpLayerFinish,
93  CcpInitRestartCounter,
94  CcpSendConfigReq,
95  CcpSentTerminateReq,
96  CcpSendTerminateAck,
97  CcpDecodeConfig,
98  CcpRecvResetReq,
99  CcpRecvResetAck
100};
101
102static const char * const ccp_TimerNames[] =
103  {"CCP restart", "CCP openmode", "CCP stopped"};
104
105static const char *
106protoname(int proto)
107{
108  static char const * const cftypes[] = {
109    /* Check out the latest ``Compression Control Protocol'' rfc (1962) */
110    "OUI",		/* 0: OUI */
111    "PRED1",		/* 1: Predictor type 1 */
112    "PRED2",		/* 2: Predictor type 2 */
113    "PUDDLE",		/* 3: Puddle Jumber */
114    NULL, NULL, NULL, NULL, NULL, NULL,
115    NULL, NULL, NULL, NULL, NULL, NULL,
116    "HWPPC",		/* 16: Hewlett-Packard PPC */
117    "STAC",		/* 17: Stac Electronics LZS (rfc1974) */
118    "MPPE",		/* 18: Microsoft PPC (rfc2118) and */
119			/*     Microsoft PPE (draft-ietf-pppext-mppe) */
120    "GAND",		/* 19: Gandalf FZA (rfc1993) */
121    "V42BIS",		/* 20: ARG->DATA.42bis compression */
122    "BSD",		/* 21: BSD LZW Compress */
123    NULL,
124    "LZS-DCP",		/* 23: LZS-DCP Compression Protocol (rfc1967) */
125    "MAGNALINK/DEFLATE",/* 24: Magnalink Variable Resource (rfc1975) */
126			/* 24: Deflate (according to pppd-2.3.*) */
127    "DCE",		/* 25: Data Circuit-Terminating Equip (rfc1976) */
128    "DEFLATE",		/* 26: Deflate (rfc1979) */
129  };
130
131  if (proto < 0 || proto > sizeof cftypes / sizeof *cftypes ||
132      cftypes[proto] == NULL)
133    return HexStr(proto, NULL, 0);
134
135  return cftypes[proto];
136}
137
138/* We support these algorithms, and Req them in the given order */
139static const struct ccp_algorithm * const algorithm[] = {
140  &DeflateAlgorithm,
141  &Pred1Algorithm,
142  &PppdDeflateAlgorithm
143#ifdef HAVE_DES
144  , &MPPEAlgorithm
145#endif
146};
147
148#define NALGORITHMS (sizeof algorithm/sizeof algorithm[0])
149
150int
151ccp_ReportStatus(struct cmdargs const *arg)
152{
153  struct ccp_opt **o;
154  struct link *l;
155  struct ccp *ccp;
156  int f;
157
158  l = command_ChooseLink(arg);
159  ccp = &l->ccp;
160
161  prompt_Printf(arg->prompt, "%s: %s [%s]\n", l->name, ccp->fsm.name,
162                State2Nam(ccp->fsm.state));
163  if (ccp->fsm.state == ST_OPENED) {
164    prompt_Printf(arg->prompt, " My protocol = %s, His protocol = %s\n",
165                  protoname(ccp->my_proto), protoname(ccp->his_proto));
166    prompt_Printf(arg->prompt, " Output: %ld --> %ld,  Input: %ld --> %ld\n",
167                  ccp->uncompout, ccp->compout,
168                  ccp->compin, ccp->uncompin);
169  }
170
171  if (ccp->in.algorithm != -1)
172    prompt_Printf(arg->prompt, "\n Input Options:  %s\n",
173                  (*algorithm[ccp->in.algorithm]->Disp)(&ccp->in.opt));
174
175  if (ccp->out.algorithm != -1) {
176    o = &ccp->out.opt;
177    for (f = 0; f < ccp->out.algorithm; f++)
178      if (IsEnabled(ccp->cfg.neg[algorithm[f]->Neg]))
179        o = &(*o)->next;
180    prompt_Printf(arg->prompt, " Output Options: %s\n",
181                  (*algorithm[ccp->out.algorithm]->Disp)(&(*o)->val));
182  }
183
184  prompt_Printf(arg->prompt, "\n Defaults: ");
185  prompt_Printf(arg->prompt, "FSM retry = %us, max %u Config"
186                " REQ%s, %u Term REQ%s\n", ccp->cfg.fsm.timeout,
187                ccp->cfg.fsm.maxreq, ccp->cfg.fsm.maxreq == 1 ? "" : "s",
188                ccp->cfg.fsm.maxtrm, ccp->cfg.fsm.maxtrm == 1 ? "" : "s");
189  prompt_Printf(arg->prompt, "           deflate windows: ");
190  prompt_Printf(arg->prompt, "incoming = %d, ", ccp->cfg.deflate.in.winsize);
191  prompt_Printf(arg->prompt, "outgoing = %d\n", ccp->cfg.deflate.out.winsize);
192#ifdef HAVE_DES
193  prompt_Printf(arg->prompt, "           MPPE: ");
194  if (ccp->cfg.mppe.keybits)
195    prompt_Printf(arg->prompt, "%d bits, ", ccp->cfg.mppe.keybits);
196  else
197    prompt_Printf(arg->prompt, "any bits, ");
198  switch (ccp->cfg.mppe.state) {
199  case MPPE_STATEFUL:
200    prompt_Printf(arg->prompt, "statefull");
201    break;
202  case MPPE_STATELESS:
203    prompt_Printf(arg->prompt, "stateless");
204    break;
205  case MPPE_ANYSTATE:
206    prompt_Printf(arg->prompt, "any state");
207    break;
208  }
209  prompt_Printf(arg->prompt, "%s\n",
210                ccp->cfg.mppe.required ? ", required" : "");
211#endif
212
213  prompt_Printf(arg->prompt, "\n           DEFLATE:    %s\n",
214                command_ShowNegval(ccp->cfg.neg[CCP_NEG_DEFLATE]));
215  prompt_Printf(arg->prompt, "           PREDICTOR1: %s\n",
216                command_ShowNegval(ccp->cfg.neg[CCP_NEG_PRED1]));
217  prompt_Printf(arg->prompt, "           DEFLATE24:  %s\n",
218                command_ShowNegval(ccp->cfg.neg[CCP_NEG_DEFLATE24]));
219#ifdef HAVE_DES
220  prompt_Printf(arg->prompt, "           MPPE:       %s\n",
221                command_ShowNegval(ccp->cfg.neg[CCP_NEG_MPPE]));
222#endif
223  return 0;
224}
225
226void
227ccp_SetupCallbacks(struct ccp *ccp)
228{
229  ccp->fsm.fn = &ccp_Callbacks;
230  ccp->fsm.FsmTimer.name = ccp_TimerNames[0];
231  ccp->fsm.OpenTimer.name = ccp_TimerNames[1];
232  ccp->fsm.StoppedTimer.name = ccp_TimerNames[2];
233}
234
235void
236ccp_Init(struct ccp *ccp, struct bundle *bundle, struct link *l,
237         const struct fsm_parent *parent)
238{
239  /* Initialise ourselves */
240
241  fsm_Init(&ccp->fsm, "CCP", PROTO_CCP, 1, CCP_MAXCODE, LogCCP,
242           bundle, l, parent, &ccp_Callbacks, ccp_TimerNames);
243
244  ccp->cfg.deflate.in.winsize = 0;
245  ccp->cfg.deflate.out.winsize = 15;
246  ccp->cfg.fsm.timeout = DEF_FSMRETRY;
247  ccp->cfg.fsm.maxreq = DEF_FSMTRIES;
248  ccp->cfg.fsm.maxtrm = DEF_FSMTRIES;
249  ccp->cfg.neg[CCP_NEG_DEFLATE] = NEG_ENABLED|NEG_ACCEPTED;
250  ccp->cfg.neg[CCP_NEG_PRED1] = NEG_ENABLED|NEG_ACCEPTED;
251  ccp->cfg.neg[CCP_NEG_DEFLATE24] = 0;
252#ifdef HAVE_DES
253  ccp->cfg.mppe.keybits = 0;
254  ccp->cfg.mppe.state = MPPE_ANYSTATE;
255  ccp->cfg.mppe.required = 0;
256  ccp->cfg.neg[CCP_NEG_MPPE] = NEG_ENABLED|NEG_ACCEPTED;
257#endif
258
259  ccp_Setup(ccp);
260}
261
262void
263ccp_Setup(struct ccp *ccp)
264{
265  /* Set ourselves up for a startup */
266  ccp->fsm.open_mode = 0;
267  ccp->his_proto = ccp->my_proto = -1;
268  ccp->reset_sent = ccp->last_reset = -1;
269  ccp->in.algorithm = ccp->out.algorithm = -1;
270  ccp->in.state = ccp->out.state = NULL;
271  ccp->in.opt.id = -1;
272  ccp->out.opt = NULL;
273  ccp->his_reject = ccp->my_reject = 0;
274  ccp->uncompout = ccp->compout = 0;
275  ccp->uncompin = ccp->compin = 0;
276}
277
278/*
279 * Is ccp *REQUIRED* ?
280 * We ask each of the configured ccp protocols if they're required and
281 * return TRUE if they are.
282 *
283 * It's not possible for the peer to reject a required ccp protocol
284 * without our state machine bringing the supporting lcp layer down.
285 *
286 * If ccp is required but not open, the NCP layer should not push
287 * any data into the link.
288 */
289int
290ccp_Required(struct ccp *ccp)
291{
292  int f;
293
294  for (f = 0; f < NALGORITHMS; f++)
295    if (IsEnabled(ccp->cfg.neg[algorithm[f]->Neg]) &&
296        (*algorithm[f]->Required)(&ccp->fsm))
297      return 1;
298
299  return 0;
300}
301
302static void
303CcpInitRestartCounter(struct fsm *fp, int what)
304{
305  /* Set fsm timer load */
306  struct ccp *ccp = fsm2ccp(fp);
307
308  fp->FsmTimer.load = ccp->cfg.fsm.timeout * SECTICKS;
309  switch (what) {
310    case FSM_REQ_TIMER:
311      fp->restart = ccp->cfg.fsm.maxreq;
312      break;
313    case FSM_TRM_TIMER:
314      fp->restart = ccp->cfg.fsm.maxtrm;
315      break;
316    default:
317      fp->restart = 1;
318      break;
319  }
320}
321
322static void
323CcpSendConfigReq(struct fsm *fp)
324{
325  /* Send config REQ please */
326  struct ccp *ccp = fsm2ccp(fp);
327  struct ccp_opt **o;
328  u_char *cp, buff[100];
329  int f, alloc;
330
331  cp = buff;
332  o = &ccp->out.opt;
333  alloc = ccp->his_reject == 0 && ccp->out.opt == NULL;
334  ccp->my_proto = -1;
335  ccp->out.algorithm = -1;
336  for (f = 0; f < NALGORITHMS; f++)
337    if (IsEnabled(ccp->cfg.neg[algorithm[f]->Neg]) &&
338        !REJECTED(ccp, algorithm[f]->id) &&
339        (*algorithm[f]->Usable)(fp)) {
340
341      if (!alloc)
342        for (o = &ccp->out.opt; *o != NULL; o = &(*o)->next)
343          if ((*o)->val.id == algorithm[f]->id && (*o)->algorithm == f)
344            break;
345
346      if (alloc || *o == NULL) {
347        *o = (struct ccp_opt *)malloc(sizeof(struct ccp_opt));
348        (*o)->val.id = algorithm[f]->id;
349        (*o)->val.len = 2;
350        (*o)->next = NULL;
351        (*o)->algorithm = f;
352        (*algorithm[f]->o.OptInit)(&(*o)->val, &ccp->cfg);
353      }
354
355      if (cp + (*o)->val.len > buff + sizeof buff) {
356        log_Printf(LogERROR, "%s: CCP REQ buffer overrun !\n", fp->link->name);
357        break;
358      }
359      memcpy(cp, &(*o)->val, (*o)->val.len);
360      cp += (*o)->val.len;
361
362      ccp->my_proto = (*o)->val.id;
363      ccp->out.algorithm = f;
364
365      if (alloc)
366        o = &(*o)->next;
367    }
368
369  fsm_Output(fp, CODE_CONFIGREQ, fp->reqid, buff, cp - buff, MB_CCPOUT);
370}
371
372void
373ccp_SendResetReq(struct fsm *fp)
374{
375  /* We can't read our input - ask peer to reset */
376  struct ccp *ccp = fsm2ccp(fp);
377
378  ccp->reset_sent = fp->reqid;
379  ccp->last_reset = -1;
380  fsm_Output(fp, CODE_RESETREQ, fp->reqid, NULL, 0, MB_CCPOUT);
381}
382
383static void
384CcpSentTerminateReq(struct fsm *fp)
385{
386  /* Term REQ just sent by FSM */
387}
388
389static void
390CcpSendTerminateAck(struct fsm *fp, u_char id)
391{
392  /* Send Term ACK please */
393  fsm_Output(fp, CODE_TERMACK, id, NULL, 0, MB_CCPOUT);
394}
395
396static int
397CcpRecvResetReq(struct fsm *fp)
398{
399  /* Got a reset REQ, reset outgoing dictionary */
400  struct ccp *ccp = fsm2ccp(fp);
401  if (ccp->out.state == NULL)
402    return 1;
403  return (*algorithm[ccp->out.algorithm]->o.Reset)(ccp->out.state);
404}
405
406static void
407CcpLayerStart(struct fsm *fp)
408{
409  /* We're about to start up ! */
410  struct ccp *ccp = fsm2ccp(fp);
411
412  log_Printf(LogCCP, "%s: LayerStart.\n", fp->link->name);
413  fp->more.reqs = fp->more.naks = fp->more.rejs = ccp->cfg.fsm.maxreq * 3;
414}
415
416static void
417CcpLayerDown(struct fsm *fp)
418{
419  /* About to come down */
420  struct ccp *ccp = fsm2ccp(fp);
421  struct ccp_opt *next;
422
423  log_Printf(LogCCP, "%s: LayerDown.\n", fp->link->name);
424  if (ccp->in.state != NULL) {
425    (*algorithm[ccp->in.algorithm]->i.Term)(ccp->in.state);
426    ccp->in.state = NULL;
427    ccp->in.algorithm = -1;
428  }
429  if (ccp->out.state != NULL) {
430    (*algorithm[ccp->out.algorithm]->o.Term)(ccp->out.state);
431    ccp->out.state = NULL;
432    ccp->out.algorithm = -1;
433  }
434  ccp->his_reject = ccp->my_reject = 0;
435
436  while (ccp->out.opt) {
437    next = ccp->out.opt->next;
438    free(ccp->out.opt);
439    ccp->out.opt = next;
440  }
441  ccp_Setup(ccp);
442}
443
444static void
445CcpLayerFinish(struct fsm *fp)
446{
447  /* We're now down */
448  struct ccp *ccp = fsm2ccp(fp);
449  struct ccp_opt *next;
450
451  log_Printf(LogCCP, "%s: LayerFinish.\n", fp->link->name);
452
453  /*
454   * Nuke options that may be left over from sending a REQ but never
455   * coming up.
456   */
457  while (ccp->out.opt) {
458    next = ccp->out.opt->next;
459    free(ccp->out.opt);
460    ccp->out.opt = next;
461  }
462
463  if (ccp_Required(ccp)) {
464    if (fp->link->lcp.fsm.state == ST_OPENED)
465      log_Printf(LogLCP, "%s: Closing due to CCP completion\n", fp->link->name);
466    fsm_Close(&fp->link->lcp.fsm);
467  }
468}
469
470/*  Called when CCP has reached the OPEN state */
471static int
472CcpLayerUp(struct fsm *fp)
473{
474  /* We're now up */
475  struct ccp *ccp = fsm2ccp(fp);
476  struct ccp_opt **o;
477  int f;
478
479  log_Printf(LogCCP, "%s: LayerUp.\n", fp->link->name);
480
481  if (ccp->in.state == NULL && ccp->in.algorithm >= 0 &&
482      ccp->in.algorithm < NALGORITHMS) {
483    ccp->in.state = (*algorithm[ccp->in.algorithm]->i.Init)(&ccp->in.opt);
484    if (ccp->in.state == NULL) {
485      log_Printf(LogERROR, "%s: %s (in) initialisation failure\n",
486                fp->link->name, protoname(ccp->his_proto));
487      ccp->his_proto = ccp->my_proto = -1;
488      fsm_Close(fp);
489      return 0;
490    }
491  }
492
493  o = &ccp->out.opt;
494  for (f = 0; f < ccp->out.algorithm; f++)
495    if (IsEnabled(ccp->cfg.neg[algorithm[f]->Neg]))
496      o = &(*o)->next;
497
498  if (ccp->out.state == NULL && ccp->out.algorithm >= 0 &&
499      ccp->out.algorithm < NALGORITHMS) {
500    ccp->out.state = (*algorithm[ccp->out.algorithm]->o.Init)(&(*o)->val);
501    if (ccp->out.state == NULL) {
502      log_Printf(LogERROR, "%s: %s (out) initialisation failure\n",
503                fp->link->name, protoname(ccp->my_proto));
504      ccp->his_proto = ccp->my_proto = -1;
505      fsm_Close(fp);
506      return 0;
507    }
508  }
509
510  fp->more.reqs = fp->more.naks = fp->more.rejs = ccp->cfg.fsm.maxreq * 3;
511
512  log_Printf(LogCCP, "%s: Out = %s[%d], In = %s[%d]\n",
513            fp->link->name, protoname(ccp->my_proto), ccp->my_proto,
514            protoname(ccp->his_proto), ccp->his_proto);
515
516  return 1;
517}
518
519static void
520CcpDecodeConfig(struct fsm *fp, u_char *cp, int plen, int mode_type,
521                struct fsm_decode *dec)
522{
523  /* Deal with incoming data */
524  struct ccp *ccp = fsm2ccp(fp);
525  int type, length, f;
526  const char *end;
527
528  if (mode_type == MODE_REQ)
529    ccp->in.algorithm = -1;	/* In case we've received two REQs in a row */
530
531  while (plen >= sizeof(struct fsmconfig)) {
532    type = *cp;
533    length = cp[1];
534
535    if (length == 0) {
536      log_Printf(LogCCP, "%s: CCP size zero\n", fp->link->name);
537      break;
538    }
539
540    if (length > sizeof(struct lcp_opt)) {
541      length = sizeof(struct lcp_opt);
542      log_Printf(LogCCP, "%s: Warning: Truncating length to %d\n",
543                fp->link->name, length);
544    }
545
546    for (f = NALGORITHMS-1; f > -1; f--)
547      if (algorithm[f]->id == type)
548        break;
549
550    end = f == -1 ? "" : (*algorithm[f]->Disp)((struct lcp_opt *)cp);
551    if (end == NULL)
552      end = "";
553
554    log_Printf(LogCCP, " %s[%d] %s\n", protoname(type), length, end);
555
556    if (f == -1) {
557      /* Don't understand that :-( */
558      if (mode_type == MODE_REQ) {
559        ccp->my_reject |= (1 << type);
560        memcpy(dec->rejend, cp, length);
561        dec->rejend += length;
562      }
563    } else {
564      struct ccp_opt *o;
565
566      switch (mode_type) {
567      case MODE_REQ:
568	if (IsAccepted(ccp->cfg.neg[algorithm[f]->Neg]) &&
569            (*algorithm[f]->Usable)(fp) &&
570            ccp->in.algorithm == -1) {
571	  memcpy(&ccp->in.opt, cp, length);
572          switch ((*algorithm[f]->i.Set)(&ccp->in.opt, &ccp->cfg)) {
573          case MODE_REJ:
574	    memcpy(dec->rejend, &ccp->in.opt, ccp->in.opt.len);
575	    dec->rejend += ccp->in.opt.len;
576            break;
577          case MODE_NAK:
578	    memcpy(dec->nakend, &ccp->in.opt, ccp->in.opt.len);
579	    dec->nakend += ccp->in.opt.len;
580            break;
581          case MODE_ACK:
582	    memcpy(dec->ackend, cp, length);
583	    dec->ackend += length;
584	    ccp->his_proto = type;
585            ccp->in.algorithm = f;		/* This one'll do :-) */
586            break;
587          }
588	} else {
589	  memcpy(dec->rejend, cp, length);
590	  dec->rejend += length;
591	}
592	break;
593      case MODE_NAK:
594        for (o = ccp->out.opt; o != NULL; o = o->next)
595          if (o->val.id == cp[0])
596            break;
597        if (o == NULL)
598          log_Printf(LogCCP, "%s: Warning: Ignoring peer NAK of unsent"
599                     " option\n", fp->link->name);
600        else {
601	  memcpy(&o->val, cp, length);
602          if ((*algorithm[f]->o.Set)(&o->val, &ccp->cfg) == MODE_ACK)
603            ccp->my_proto = algorithm[f]->id;
604          else {
605	    ccp->his_reject |= (1 << type);
606	    ccp->my_proto = -1;
607            if (algorithm[f]->Required(fp)) {
608              log_Printf(LogWARN, "%s: Cannot understand peers (required)"
609                         " %s negotiation\n", fp->link->name,
610                         protoname(algorithm[f]->id));
611              fsm_Close(&fp->link->lcp.fsm);
612            }
613          }
614        }
615        break;
616      case MODE_REJ:
617	ccp->his_reject |= (1 << type);
618	ccp->my_proto = -1;
619        if (algorithm[f]->Required(fp)) {
620          log_Printf(LogWARN, "%s: Peer rejected (required) %s negotiation\n",
621                     fp->link->name, protoname(algorithm[f]->id));
622          fsm_Close(&fp->link->lcp.fsm);
623        }
624	break;
625      }
626    }
627
628    plen -= cp[1];
629    cp += cp[1];
630  }
631
632  if (mode_type != MODE_NOP) {
633    if (dec->rejend != dec->rej) {
634      /* rejects are preferred */
635      dec->ackend = dec->ack;
636      dec->nakend = dec->nak;
637      if (ccp->in.state == NULL) {
638        ccp->his_proto = -1;
639        ccp->in.algorithm = -1;
640      }
641    } else if (dec->nakend != dec->nak) {
642      /* then NAKs */
643      dec->ackend = dec->ack;
644      if (ccp->in.state == NULL) {
645        ccp->his_proto = -1;
646        ccp->in.algorithm = -1;
647      }
648    }
649  }
650}
651
652extern struct mbuf *
653ccp_Input(struct bundle *bundle, struct link *l, struct mbuf *bp)
654{
655  /* Got PROTO_CCP from link */
656  m_settype(bp, MB_CCPIN);
657  if (bundle_Phase(bundle) == PHASE_NETWORK)
658    fsm_Input(&l->ccp.fsm, bp);
659  else {
660    if (bundle_Phase(bundle) < PHASE_NETWORK)
661      log_Printf(LogCCP, "%s: Error: Unexpected CCP in phase %s (ignored)\n",
662                 l->ccp.fsm.link->name, bundle_PhaseName(bundle));
663    m_freem(bp);
664  }
665  return NULL;
666}
667
668static void
669CcpRecvResetAck(struct fsm *fp, u_char id)
670{
671  /* Got a reset ACK, reset incoming dictionary */
672  struct ccp *ccp = fsm2ccp(fp);
673
674  if (ccp->reset_sent != -1) {
675    if (id != ccp->reset_sent) {
676      log_Printf(LogCCP, "%s: Incorrect ResetAck (id %d, not %d)"
677                " ignored\n", fp->link->name, id, ccp->reset_sent);
678      return;
679    }
680    /* Whaddaya know - a correct reset ack */
681  } else if (id == ccp->last_reset)
682    log_Printf(LogCCP, "%s: Duplicate ResetAck (resetting again)\n",
683               fp->link->name);
684  else {
685    log_Printf(LogCCP, "%s: Unexpected ResetAck (id %d) ignored\n",
686               fp->link->name, id);
687    return;
688  }
689
690  ccp->last_reset = ccp->reset_sent;
691  ccp->reset_sent = -1;
692  if (ccp->in.state != NULL)
693    (*algorithm[ccp->in.algorithm]->i.Reset)(ccp->in.state);
694}
695
696static struct mbuf *
697ccp_LayerPush(struct bundle *b, struct link *l, struct mbuf *bp,
698              int pri, u_short *proto)
699{
700  if (PROTO_COMPRESSIBLE(*proto)) {
701    if (l->ccp.fsm.state != ST_OPENED) {
702      if (ccp_Required(&l->ccp)) {
703        /* The NCP layer shouldn't have let this happen ! */
704        log_Printf(LogERROR, "%s: Unexpected attempt to use an unopened and"
705                   " required CCP layer\n", l->name);
706        m_freem(bp);
707        bp = NULL;
708      }
709    } else if (l->ccp.out.state != NULL) {
710      bp = (*algorithm[l->ccp.out.algorithm]->o.Write)
711             (l->ccp.out.state, &l->ccp, l, pri, proto, bp);
712      switch (*proto) {
713        case PROTO_ICOMPD:
714          m_settype(bp, MB_ICOMPDOUT);
715          break;
716        case PROTO_COMPD:
717          m_settype(bp, MB_COMPDOUT);
718          break;
719      }
720    }
721  }
722
723  return bp;
724}
725
726static struct mbuf *
727ccp_LayerPull(struct bundle *b, struct link *l, struct mbuf *bp, u_short *proto)
728{
729  /*
730   * If proto isn't PROTO_[I]COMPD, we still want to pass it to the
731   * decompression routines so that the dictionary's updated
732   */
733  if (l->ccp.fsm.state == ST_OPENED) {
734    if (*proto == PROTO_COMPD || *proto == PROTO_ICOMPD) {
735      log_Printf(LogDEBUG, "ccp_LayerPull: PROTO_%sCOMPDP -> PROTO_IP\n",
736                 *proto == PROTO_ICOMPD ? "I" : "");
737      /* Decompress incoming data */
738      if (l->ccp.reset_sent != -1)
739        /* Send another REQ and put the packet in the bit bucket */
740        fsm_Output(&l->ccp.fsm, CODE_RESETREQ, l->ccp.reset_sent, NULL, 0,
741                   MB_CCPOUT);
742      else if (l->ccp.in.state != NULL) {
743        bp = (*algorithm[l->ccp.in.algorithm]->i.Read)
744               (l->ccp.in.state, &l->ccp, proto, bp);
745        switch (*proto) {
746          case PROTO_ICOMPD:
747            m_settype(bp, MB_ICOMPDIN);
748            break;
749          case PROTO_COMPD:
750            m_settype(bp, MB_COMPDIN);
751            break;
752        }
753        return bp;
754      }
755      m_freem(bp);
756      bp = NULL;
757    } else if (PROTO_COMPRESSIBLE(*proto) && l->ccp.in.state != NULL) {
758      log_Printf(LogDEBUG, "ccp_LayerPull: Ignore packet (dict only)\n");
759      /* Add incoming Network Layer traffic to our dictionary */
760      (*algorithm[l->ccp.in.algorithm]->i.DictSetup)
761        (l->ccp.in.state, &l->ccp, *proto, bp);
762    } else
763      log_Printf(LogDEBUG, "ccp_LayerPull: Ignore packet\n");
764  }
765
766  return bp;
767}
768
769u_short
770ccp_Proto(struct ccp *ccp)
771{
772  return !link2physical(ccp->fsm.link) || !ccp->fsm.bundle->ncp.mp.active ?
773         PROTO_COMPD : PROTO_ICOMPD;
774}
775
776int
777ccp_SetOpenMode(struct ccp *ccp)
778{
779  int f;
780
781  for (f = 0; f < CCP_NEG_TOTAL; f++)
782    if (IsEnabled(ccp->cfg.neg[f])) {
783      ccp->fsm.open_mode = 0;
784      return 1;
785    }
786
787  ccp->fsm.open_mode = OPEN_PASSIVE;	/* Go straight to ST_STOPPED ? */
788
789  for (f = 0; f < CCP_NEG_TOTAL; f++)
790    if (IsAccepted(ccp->cfg.neg[f]))
791      return 1;
792
793  return 0;				/* No CCP at all */
794}
795
796int
797ccp_DefaultUsable(struct fsm *fp)
798{
799  return 1;
800}
801
802int
803ccp_DefaultRequired(struct fsm *fp)
804{
805  return 0;
806}
807
808struct layer ccplayer = { LAYER_CCP, "ccp", ccp_LayerPush, ccp_LayerPull };
809