ccp.c revision 134789 
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 134789 2004-09-05 01:46:52Z 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/socket.h>
36#include <sys/un.h>
37
38#include <stdarg.h>
39#include <stdio.h>
40#include <stdlib.h>
41#include <string.h>	/* memcpy() on some archs */
42#include <termios.h>
43
44#include "layer.h"
45#include "defs.h"
46#include "command.h"
47#include "mbuf.h"
48#include "log.h"
49#include "timer.h"
50#include "fsm.h"
51#include "proto.h"
52#include "pred.h"
53#include "deflate.h"
54#include "throughput.h"
55#include "iplist.h"
56#include "slcompress.h"
57#include "lqr.h"
58#include "hdlc.h"
59#include "lcp.h"
60#include "ccp.h"
61#include "ncpaddr.h"
62#include "ipcp.h"
63#include "filter.h"
64#include "descriptor.h"
65#include "prompt.h"
66#include "link.h"
67#include "mp.h"
68#include "async.h"
69#include "physical.h"
70#ifndef NORADIUS
71#include "radius.h"
72#endif
73#ifndef NODES
74#include "mppe.h"
75#endif
76#include "ipv6cp.h"
77#include "ncp.h"
78#include "bundle.h"
79
80static void CcpSendConfigReq(struct fsm *);
81static void CcpSentTerminateReq(struct fsm *);
82static void CcpSendTerminateAck(struct fsm *, u_char);
83static void CcpDecodeConfig(struct fsm *, u_char *, u_char *, int,
84                            struct fsm_decode *);
85static void CcpLayerStart(struct fsm *);
86static void CcpLayerFinish(struct fsm *);
87static int CcpLayerUp(struct fsm *);
88static void CcpLayerDown(struct fsm *);
89static void CcpInitRestartCounter(struct fsm *, int);
90static int CcpRecvResetReq(struct fsm *);
91static void CcpRecvResetAck(struct fsm *, u_char);
92
93static struct fsm_callbacks ccp_Callbacks = {
94  CcpLayerUp,
95  CcpLayerDown,
96  CcpLayerStart,
97  CcpLayerFinish,
98  CcpInitRestartCounter,
99  CcpSendConfigReq,
100  CcpSentTerminateReq,
101  CcpSendTerminateAck,
102  CcpDecodeConfig,
103  CcpRecvResetReq,
104  CcpRecvResetAck
105};
106
107static const char * const ccp_TimerNames[] =
108  {"CCP restart", "CCP openmode", "CCP stopped"};
109
110static const char *
111protoname(int proto)
112{
113  static char const * const cftypes[] = {
114    /* Check out the latest ``Compression Control Protocol'' rfc (1962) */
115    "OUI",		/* 0: OUI */
116    "PRED1",		/* 1: Predictor type 1 */
117    "PRED2",		/* 2: Predictor type 2 */
118    "PUDDLE",		/* 3: Puddle Jumber */
119    NULL, NULL, NULL, NULL, NULL, NULL,
120    NULL, NULL, NULL, NULL, NULL, NULL,
121    "HWPPC",		/* 16: Hewlett-Packard PPC */
122    "STAC",		/* 17: Stac Electronics LZS (rfc1974) */
123    "MPPE",		/* 18: Microsoft PPC (rfc2118) and */
124			/*     Microsoft PPE (draft-ietf-pppext-mppe) */
125    "GAND",		/* 19: Gandalf FZA (rfc1993) */
126    "V42BIS",		/* 20: ARG->DATA.42bis compression */
127    "BSD",		/* 21: BSD LZW Compress */
128    NULL,
129    "LZS-DCP",		/* 23: LZS-DCP Compression Protocol (rfc1967) */
130    "MAGNALINK/DEFLATE",/* 24: Magnalink Variable Resource (rfc1975) */
131			/* 24: Deflate (according to pppd-2.3.*) */
132    "DCE",		/* 25: Data Circuit-Terminating Equip (rfc1976) */
133    "DEFLATE",		/* 26: Deflate (rfc1979) */
134  };
135
136  if (proto < 0 || (unsigned)proto > sizeof cftypes / sizeof *cftypes ||
137      cftypes[proto] == NULL) {
138    if (proto == -1)
139      return "none";
140    return HexStr(proto, NULL, 0);
141  }
142
143  return cftypes[proto];
144}
145
146/* We support these algorithms, and Req them in the given order */
147static const struct ccp_algorithm * const algorithm[] = {
148  &DeflateAlgorithm,
149  &Pred1Algorithm,
150  &PppdDeflateAlgorithm
151#ifndef NODES
152  , &MPPEAlgorithm
153#endif
154};
155
156#define NALGORITHMS (sizeof algorithm/sizeof algorithm[0])
157
158int
159ccp_ReportStatus(struct cmdargs const *arg)
160{
161  struct ccp_opt **o;
162  struct link *l;
163  struct ccp *ccp;
164  int f;
165
166  l = command_ChooseLink(arg);
167  ccp = &l->ccp;
168
169  prompt_Printf(arg->prompt, "%s: %s [%s]\n", l->name, ccp->fsm.name,
170                State2Nam(ccp->fsm.state));
171  if (ccp->fsm.state == ST_OPENED) {
172    prompt_Printf(arg->prompt, " My protocol = %s, His protocol = %s\n",
173                  protoname(ccp->my_proto), protoname(ccp->his_proto));
174    prompt_Printf(arg->prompt, " Output: %ld --> %ld,  Input: %ld --> %ld\n",
175                  ccp->uncompout, ccp->compout,
176                  ccp->compin, ccp->uncompin);
177  }
178
179  if (ccp->in.algorithm != -1)
180    prompt_Printf(arg->prompt, "\n Input Options:  %s\n",
181                  (*algorithm[ccp->in.algorithm]->Disp)(&ccp->in.opt));
182
183  if (ccp->out.algorithm != -1) {
184    o = &ccp->out.opt;
185    for (f = 0; f < ccp->out.algorithm; f++)
186      if (IsEnabled(ccp->cfg.neg[algorithm[f]->Neg]))
187        o = &(*o)->next;
188    prompt_Printf(arg->prompt, " Output Options: %s\n",
189                  (*algorithm[ccp->out.algorithm]->Disp)(&(*o)->val));
190  }
191
192  prompt_Printf(arg->prompt, "\n Defaults: ");
193  prompt_Printf(arg->prompt, "FSM retry = %us, max %u Config"
194                " REQ%s, %u Term REQ%s\n", ccp->cfg.fsm.timeout,
195                ccp->cfg.fsm.maxreq, ccp->cfg.fsm.maxreq == 1 ? "" : "s",
196                ccp->cfg.fsm.maxtrm, ccp->cfg.fsm.maxtrm == 1 ? "" : "s");
197  prompt_Printf(arg->prompt, "           deflate windows: ");
198  prompt_Printf(arg->prompt, "incoming = %d, ", ccp->cfg.deflate.in.winsize);
199  prompt_Printf(arg->prompt, "outgoing = %d\n", ccp->cfg.deflate.out.winsize);
200#ifndef NODES
201  prompt_Printf(arg->prompt, "           MPPE: ");
202  if (ccp->cfg.mppe.keybits)
203    prompt_Printf(arg->prompt, "%d bits, ", ccp->cfg.mppe.keybits);
204  else
205    prompt_Printf(arg->prompt, "any bits, ");
206  switch (ccp->cfg.mppe.state) {
207  case MPPE_STATEFUL:
208    prompt_Printf(arg->prompt, "stateful");
209    break;
210  case MPPE_STATELESS:
211    prompt_Printf(arg->prompt, "stateless");
212    break;
213  case MPPE_ANYSTATE:
214    prompt_Printf(arg->prompt, "any state");
215    break;
216  }
217  prompt_Printf(arg->prompt, "%s\n",
218                ccp->cfg.mppe.required ? ", required" : "");
219#endif
220
221  prompt_Printf(arg->prompt, "\n           DEFLATE:    %s\n",
222                command_ShowNegval(ccp->cfg.neg[CCP_NEG_DEFLATE]));
223  prompt_Printf(arg->prompt, "           PREDICTOR1: %s\n",
224                command_ShowNegval(ccp->cfg.neg[CCP_NEG_PRED1]));
225  prompt_Printf(arg->prompt, "           DEFLATE24:  %s\n",
226                command_ShowNegval(ccp->cfg.neg[CCP_NEG_DEFLATE24]));
227#ifndef NODES
228  prompt_Printf(arg->prompt, "           MPPE:       %s\n",
229                command_ShowNegval(ccp->cfg.neg[CCP_NEG_MPPE]));
230#endif
231  return 0;
232}
233
234void
235ccp_SetupCallbacks(struct ccp *ccp)
236{
237  ccp->fsm.fn = &ccp_Callbacks;
238  ccp->fsm.FsmTimer.name = ccp_TimerNames[0];
239  ccp->fsm.OpenTimer.name = ccp_TimerNames[1];
240  ccp->fsm.StoppedTimer.name = ccp_TimerNames[2];
241}
242
243void
244ccp_Init(struct ccp *ccp, struct bundle *bundle, struct link *l,
245         const struct fsm_parent *parent)
246{
247  /* Initialise ourselves */
248
249  fsm_Init(&ccp->fsm, "CCP", PROTO_CCP, 1, CCP_MAXCODE, LogCCP,
250           bundle, l, parent, &ccp_Callbacks, ccp_TimerNames);
251
252  ccp->cfg.deflate.in.winsize = 0;
253  ccp->cfg.deflate.out.winsize = 15;
254  ccp->cfg.fsm.timeout = DEF_FSMRETRY;
255  ccp->cfg.fsm.maxreq = DEF_FSMTRIES;
256  ccp->cfg.fsm.maxtrm = DEF_FSMTRIES;
257  ccp->cfg.neg[CCP_NEG_DEFLATE] = NEG_ENABLED|NEG_ACCEPTED;
258  ccp->cfg.neg[CCP_NEG_PRED1] = NEG_ENABLED|NEG_ACCEPTED;
259  ccp->cfg.neg[CCP_NEG_DEFLATE24] = 0;
260#ifndef NODES
261  ccp->cfg.mppe.keybits = 0;
262  ccp->cfg.mppe.state = MPPE_ANYSTATE;
263  ccp->cfg.mppe.required = 0;
264  ccp->cfg.neg[CCP_NEG_MPPE] = NEG_ENABLED|NEG_ACCEPTED;
265#endif
266
267  ccp_Setup(ccp);
268}
269
270void
271ccp_Setup(struct ccp *ccp)
272{
273  /* Set ourselves up for a startup */
274  ccp->fsm.open_mode = 0;
275  ccp->his_proto = ccp->my_proto = -1;
276  ccp->reset_sent = ccp->last_reset = -1;
277  ccp->in.algorithm = ccp->out.algorithm = -1;
278  ccp->in.state = ccp->out.state = NULL;
279  ccp->in.opt.hdr.id = -1;
280  ccp->out.opt = NULL;
281  ccp->his_reject = ccp->my_reject = 0;
282  ccp->uncompout = ccp->compout = 0;
283  ccp->uncompin = ccp->compin = 0;
284}
285
286/*
287 * Is ccp *REQUIRED* ?
288 * We ask each of the configured ccp protocols if they're required and
289 * return TRUE if they are.
290 *
291 * It's not possible for the peer to reject a required ccp protocol
292 * without our state machine bringing the supporting lcp layer down.
293 *
294 * If ccp is required but not open, the NCP layer should not push
295 * any data into the link.
296 */
297int
298ccp_Required(struct ccp *ccp)
299{
300  unsigned f;
301
302  for (f = 0; f < NALGORITHMS; f++)
303    if (IsEnabled(ccp->cfg.neg[algorithm[f]->Neg]) &&
304        (*algorithm[f]->Required)(&ccp->fsm))
305      return 1;
306
307  return 0;
308}
309
310/*
311 * Report whether it's possible to increase a packet's size after
312 * compression (and by how much).
313 */
314int
315ccp_MTUOverhead(struct ccp *ccp)
316{
317  if (ccp->fsm.state == ST_OPENED && ccp->out.algorithm >= 0)
318    return algorithm[ccp->out.algorithm]->o.MTUOverhead;
319
320  return 0;
321}
322
323static void
324CcpInitRestartCounter(struct fsm *fp, int what)
325{
326  /* Set fsm timer load */
327  struct ccp *ccp = fsm2ccp(fp);
328
329  fp->FsmTimer.load = ccp->cfg.fsm.timeout * SECTICKS;
330  switch (what) {
331    case FSM_REQ_TIMER:
332      fp->restart = ccp->cfg.fsm.maxreq;
333      break;
334    case FSM_TRM_TIMER:
335      fp->restart = ccp->cfg.fsm.maxtrm;
336      break;
337    default:
338      fp->restart = 1;
339      break;
340  }
341}
342
343static void
344CcpSendConfigReq(struct fsm *fp)
345{
346  /* Send config REQ please */
347  struct ccp *ccp = fsm2ccp(fp);
348  struct ccp_opt **o;
349  u_char *cp, buff[100];
350  unsigned f;
351  int alloc;
352
353  cp = buff;
354  o = &ccp->out.opt;
355  alloc = ccp->his_reject == 0 && ccp->out.opt == NULL;
356  ccp->my_proto = -1;
357  ccp->out.algorithm = -1;
358  for (f = 0; f < NALGORITHMS; f++)
359    if (IsEnabled(ccp->cfg.neg[algorithm[f]->Neg]) &&
360        !REJECTED(ccp, algorithm[f]->id) &&
361        (*algorithm[f]->Usable)(fp)) {
362
363      if (!alloc)
364        for (o = &ccp->out.opt; *o != NULL; o = &(*o)->next)
365          if ((*o)->val.hdr.id == algorithm[f]->id && (*o)->algorithm == (int)f)
366            break;
367
368      if (alloc || *o == NULL) {
369        *o = (struct ccp_opt *)malloc(sizeof(struct ccp_opt));
370        (*o)->val.hdr.id = algorithm[f]->id;
371        (*o)->val.hdr.len = 2;
372        (*o)->next = NULL;
373        (*o)->algorithm = f;
374        (*algorithm[f]->o.OptInit)(fp->bundle, &(*o)->val, &ccp->cfg);
375      }
376
377      if (cp + (*o)->val.hdr.len > buff + sizeof buff) {
378        log_Printf(LogERROR, "%s: CCP REQ buffer overrun !\n", fp->link->name);
379        break;
380      }
381      memcpy(cp, &(*o)->val, (*o)->val.hdr.len);
382      cp += (*o)->val.hdr.len;
383
384      ccp->my_proto = (*o)->val.hdr.id;
385      ccp->out.algorithm = f;
386
387      if (alloc)
388        o = &(*o)->next;
389    }
390
391  fsm_Output(fp, CODE_CONFIGREQ, fp->reqid, buff, cp - buff, MB_CCPOUT);
392}
393
394void
395ccp_SendResetReq(struct fsm *fp)
396{
397  /* We can't read our input - ask peer to reset */
398  struct ccp *ccp = fsm2ccp(fp);
399
400  ccp->reset_sent = fp->reqid;
401  ccp->last_reset = -1;
402  fsm_Output(fp, CODE_RESETREQ, fp->reqid, NULL, 0, MB_CCPOUT);
403}
404
405static void
406CcpSentTerminateReq(struct fsm *fp __unused)
407{
408  /* Term REQ just sent by FSM */
409}
410
411static void
412CcpSendTerminateAck(struct fsm *fp, u_char id)
413{
414  /* Send Term ACK please */
415  fsm_Output(fp, CODE_TERMACK, id, NULL, 0, MB_CCPOUT);
416}
417
418static int
419CcpRecvResetReq(struct fsm *fp)
420{
421  /* Got a reset REQ, reset outgoing dictionary */
422  struct ccp *ccp = fsm2ccp(fp);
423  if (ccp->out.state == NULL)
424    return 1;
425  return (*algorithm[ccp->out.algorithm]->o.Reset)(ccp->out.state);
426}
427
428static void
429CcpLayerStart(struct fsm *fp)
430{
431  /* We're about to start up ! */
432  struct ccp *ccp = fsm2ccp(fp);
433
434  log_Printf(LogCCP, "%s: LayerStart.\n", fp->link->name);
435  fp->more.reqs = fp->more.naks = fp->more.rejs = ccp->cfg.fsm.maxreq * 3;
436}
437
438static void
439CcpLayerDown(struct fsm *fp)
440{
441  /* About to come down */
442  struct ccp *ccp = fsm2ccp(fp);
443  struct ccp_opt *next;
444
445  log_Printf(LogCCP, "%s: LayerDown.\n", fp->link->name);
446  if (ccp->in.state != NULL) {
447    (*algorithm[ccp->in.algorithm]->i.Term)(ccp->in.state);
448    ccp->in.state = NULL;
449    ccp->in.algorithm = -1;
450  }
451  if (ccp->out.state != NULL) {
452    (*algorithm[ccp->out.algorithm]->o.Term)(ccp->out.state);
453    ccp->out.state = NULL;
454    ccp->out.algorithm = -1;
455  }
456  ccp->his_reject = ccp->my_reject = 0;
457
458  while (ccp->out.opt) {
459    next = ccp->out.opt->next;
460    free(ccp->out.opt);
461    ccp->out.opt = next;
462  }
463  ccp_Setup(ccp);
464}
465
466static void
467CcpLayerFinish(struct fsm *fp)
468{
469  /* We're now down */
470  struct ccp *ccp = fsm2ccp(fp);
471  struct ccp_opt *next;
472
473  log_Printf(LogCCP, "%s: LayerFinish.\n", fp->link->name);
474
475  /*
476   * Nuke options that may be left over from sending a REQ but never
477   * coming up.
478   */
479  while (ccp->out.opt) {
480    next = ccp->out.opt->next;
481    free(ccp->out.opt);
482    ccp->out.opt = next;
483  }
484
485  if (ccp_Required(ccp)) {
486    if (fp->link->lcp.fsm.state == ST_OPENED)
487      log_Printf(LogLCP, "%s: Closing due to CCP completion\n", fp->link->name);
488    fsm_Close(&fp->link->lcp.fsm);
489  }
490}
491
492/*  Called when CCP has reached the OPEN state */
493static int
494CcpLayerUp(struct fsm *fp)
495{
496  /* We're now up */
497  struct ccp *ccp = fsm2ccp(fp);
498  struct ccp_opt **o;
499  unsigned f, fail;
500
501  for (f = fail = 0; f < NALGORITHMS; f++)
502    if (IsEnabled(ccp->cfg.neg[algorithm[f]->Neg]) &&
503        (*algorithm[f]->Required)(&ccp->fsm) &&
504        (ccp->in.algorithm != (int)f || ccp->out.algorithm != (int)f)) {
505      /* Blow it all away - we haven't negotiated a required algorithm */
506      log_Printf(LogWARN, "%s: Failed to negotiate (required) %s\n",
507                 fp->link->name, protoname(algorithm[f]->id));
508      fail = 1;
509    }
510
511  if (fail) {
512    ccp->his_proto = ccp->my_proto = -1;
513    fsm_Close(fp);
514    fsm_Close(&fp->link->lcp.fsm);
515    return 0;
516  }
517
518  log_Printf(LogCCP, "%s: LayerUp.\n", fp->link->name);
519
520  if (ccp->in.state == NULL && ccp->in.algorithm >= 0 &&
521      ccp->in.algorithm < (int)NALGORITHMS) {
522    ccp->in.state = (*algorithm[ccp->in.algorithm]->i.Init)
523      (fp->bundle, &ccp->in.opt);
524    if (ccp->in.state == NULL) {
525      log_Printf(LogERROR, "%s: %s (in) initialisation failure\n",
526                fp->link->name, protoname(ccp->his_proto));
527      ccp->his_proto = ccp->my_proto = -1;
528      fsm_Close(fp);
529      return 0;
530    }
531  }
532
533  o = &ccp->out.opt;
534  if (ccp->out.algorithm > 0)
535    for (f = 0; f < (unsigned)ccp->out.algorithm; f++)
536      if (IsEnabled(ccp->cfg.neg[algorithm[f]->Neg]))
537	o = &(*o)->next;
538
539  if (ccp->out.state == NULL && ccp->out.algorithm >= 0 &&
540      ccp->out.algorithm < (int)NALGORITHMS) {
541    ccp->out.state = (*algorithm[ccp->out.algorithm]->o.Init)
542      (fp->bundle, &(*o)->val);
543    if (ccp->out.state == NULL) {
544      log_Printf(LogERROR, "%s: %s (out) initialisation failure\n",
545                fp->link->name, protoname(ccp->my_proto));
546      ccp->his_proto = ccp->my_proto = -1;
547      fsm_Close(fp);
548      return 0;
549    }
550  }
551
552  fp->more.reqs = fp->more.naks = fp->more.rejs = ccp->cfg.fsm.maxreq * 3;
553
554  log_Printf(LogCCP, "%s: Out = %s[%d], In = %s[%d]\n",
555            fp->link->name, protoname(ccp->my_proto), ccp->my_proto,
556            protoname(ccp->his_proto), ccp->his_proto);
557
558  return 1;
559}
560
561static void
562CcpDecodeConfig(struct fsm *fp, u_char *cp, u_char *end, int mode_type,
563                struct fsm_decode *dec)
564{
565  /* Deal with incoming data */
566  struct ccp *ccp = fsm2ccp(fp);
567  int f;
568  const char *disp;
569  struct fsm_opt *opt;
570
571  if (mode_type == MODE_REQ)
572    ccp->in.algorithm = -1;	/* In case we've received two REQs in a row */
573
574  while (end >= cp + sizeof(opt->hdr)) {
575    if ((opt = fsm_readopt(&cp)) == NULL)
576      break;
577
578    for (f = NALGORITHMS-1; f > -1; f--)
579      if (algorithm[f]->id == opt->hdr.id)
580        break;
581
582    disp = f == -1 ? "" : (*algorithm[f]->Disp)(opt);
583    if (disp == NULL)
584      disp = "";
585
586    log_Printf(LogCCP, " %s[%d] %s\n", protoname(opt->hdr.id),
587               opt->hdr.len, disp);
588
589    if (f == -1) {
590      /* Don't understand that :-( */
591      if (mode_type == MODE_REQ) {
592        ccp->my_reject |= (1 << opt->hdr.id);
593        fsm_rej(dec, opt);
594      }
595    } else {
596      struct ccp_opt *o;
597
598      switch (mode_type) {
599      case MODE_REQ:
600        if (IsAccepted(ccp->cfg.neg[algorithm[f]->Neg]) &&
601            (*algorithm[f]->Usable)(fp) &&
602            ccp->in.algorithm == -1) {
603          memcpy(&ccp->in.opt, opt, opt->hdr.len);
604          switch ((*algorithm[f]->i.Set)(fp->bundle, &ccp->in.opt, &ccp->cfg)) {
605          case MODE_REJ:
606            fsm_rej(dec, &ccp->in.opt);
607            break;
608          case MODE_NAK:
609            fsm_nak(dec, &ccp->in.opt);
610            break;
611          case MODE_ACK:
612            fsm_ack(dec, &ccp->in.opt);
613            ccp->his_proto = opt->hdr.id;
614            ccp->in.algorithm = (int)f;		/* This one'll do :-) */
615            break;
616          }
617        } else {
618          fsm_rej(dec, opt);
619        }
620        break;
621      case MODE_NAK:
622        for (o = ccp->out.opt; o != NULL; o = o->next)
623          if (o->val.hdr.id == opt->hdr.id)
624            break;
625        if (o == NULL)
626          log_Printf(LogCCP, "%s: Warning: Ignoring peer NAK of unsent"
627                     " option\n", fp->link->name);
628        else {
629          memcpy(&o->val, opt, opt->hdr.len);
630          if ((*algorithm[f]->o.Set)(fp->bundle, &o->val, &ccp->cfg) ==
631              MODE_ACK)
632            ccp->my_proto = algorithm[f]->id;
633          else {
634            ccp->his_reject |= (1 << opt->hdr.id);
635            ccp->my_proto = -1;
636            if (algorithm[f]->Required(fp)) {
637              log_Printf(LogWARN, "%s: Cannot understand peers (required)"
638                         " %s negotiation\n", fp->link->name,
639                         protoname(algorithm[f]->id));
640              fsm_Close(&fp->link->lcp.fsm);
641            }
642          }
643        }
644        break;
645      case MODE_REJ:
646        ccp->his_reject |= (1 << opt->hdr.id);
647        ccp->my_proto = -1;
648        if (algorithm[f]->Required(fp)) {
649          log_Printf(LogWARN, "%s: Peer rejected (required) %s negotiation\n",
650                     fp->link->name, protoname(algorithm[f]->id));
651          fsm_Close(&fp->link->lcp.fsm);
652        }
653        break;
654      }
655    }
656  }
657
658  if (mode_type != MODE_NOP) {
659    fsm_opt_normalise(dec);
660    if (dec->rejend != dec->rej || dec->nakend != dec->nak) {
661      if (ccp->in.state == NULL) {
662        ccp->his_proto = -1;
663        ccp->in.algorithm = -1;
664      }
665    }
666  }
667}
668
669extern struct mbuf *
670ccp_Input(struct bundle *bundle, struct link *l, struct mbuf *bp)
671{
672  /* Got PROTO_CCP from link */
673  m_settype(bp, MB_CCPIN);
674  if (bundle_Phase(bundle) == PHASE_NETWORK)
675    fsm_Input(&l->ccp.fsm, bp);
676  else {
677    if (bundle_Phase(bundle) < PHASE_NETWORK)
678      log_Printf(LogCCP, "%s: Error: Unexpected CCP in phase %s (ignored)\n",
679                 l->ccp.fsm.link->name, bundle_PhaseName(bundle));
680    m_freem(bp);
681  }
682  return NULL;
683}
684
685static void
686CcpRecvResetAck(struct fsm *fp, u_char id)
687{
688  /* Got a reset ACK, reset incoming dictionary */
689  struct ccp *ccp = fsm2ccp(fp);
690
691  if (ccp->reset_sent != -1) {
692    if (id != ccp->reset_sent) {
693      log_Printf(LogCCP, "%s: Incorrect ResetAck (id %d, not %d)"
694                " ignored\n", fp->link->name, id, ccp->reset_sent);
695      return;
696    }
697    /* Whaddaya know - a correct reset ack */
698  } else if (id == ccp->last_reset)
699    log_Printf(LogCCP, "%s: Duplicate ResetAck (resetting again)\n",
700               fp->link->name);
701  else {
702    log_Printf(LogCCP, "%s: Unexpected ResetAck (id %d) ignored\n",
703               fp->link->name, id);
704    return;
705  }
706
707  ccp->last_reset = ccp->reset_sent;
708  ccp->reset_sent = -1;
709  if (ccp->in.state != NULL)
710    (*algorithm[ccp->in.algorithm]->i.Reset)(ccp->in.state);
711}
712
713static struct mbuf *
714ccp_LayerPush(struct bundle *b __unused, struct link *l, struct mbuf *bp,
715              int pri, u_short *proto)
716{
717  if (PROTO_COMPRESSIBLE(*proto)) {
718    if (l->ccp.fsm.state != ST_OPENED) {
719      if (ccp_Required(&l->ccp)) {
720        /* The NCP layer shouldn't have let this happen ! */
721        log_Printf(LogERROR, "%s: Unexpected attempt to use an unopened and"
722                   " required CCP layer\n", l->name);
723        m_freem(bp);
724        bp = NULL;
725      }
726    } else if (l->ccp.out.state != NULL) {
727      bp = (*algorithm[l->ccp.out.algorithm]->o.Write)
728             (l->ccp.out.state, &l->ccp, l, pri, proto, bp);
729      switch (*proto) {
730        case PROTO_ICOMPD:
731          m_settype(bp, MB_ICOMPDOUT);
732          break;
733        case PROTO_COMPD:
734          m_settype(bp, MB_COMPDOUT);
735          break;
736      }
737    }
738  }
739
740  return bp;
741}
742
743static struct mbuf *
744ccp_LayerPull(struct bundle *b __unused, struct link *l, struct mbuf *bp,
745	      u_short *proto)
746{
747  /*
748   * If proto isn't PROTO_[I]COMPD, we still want to pass it to the
749   * decompression routines so that the dictionary's updated
750   */
751  if (l->ccp.fsm.state == ST_OPENED) {
752    if (*proto == PROTO_COMPD || *proto == PROTO_ICOMPD) {
753      /* Decompress incoming data */
754      if (l->ccp.reset_sent != -1)
755        /* Send another REQ and put the packet in the bit bucket */
756        fsm_Output(&l->ccp.fsm, CODE_RESETREQ, l->ccp.reset_sent, NULL, 0,
757                   MB_CCPOUT);
758      else if (l->ccp.in.state != NULL) {
759        bp = (*algorithm[l->ccp.in.algorithm]->i.Read)
760               (l->ccp.in.state, &l->ccp, proto, bp);
761        switch (*proto) {
762          case PROTO_ICOMPD:
763            m_settype(bp, MB_ICOMPDIN);
764            break;
765          case PROTO_COMPD:
766            m_settype(bp, MB_COMPDIN);
767            break;
768        }
769        return bp;
770      }
771      m_freem(bp);
772      bp = NULL;
773    } else if (PROTO_COMPRESSIBLE(*proto) && l->ccp.in.state != NULL) {
774      /* Add incoming Network Layer traffic to our dictionary */
775      (*algorithm[l->ccp.in.algorithm]->i.DictSetup)
776        (l->ccp.in.state, &l->ccp, *proto, bp);
777    }
778  }
779
780  return bp;
781}
782
783u_short
784ccp_Proto(struct ccp *ccp)
785{
786  return !link2physical(ccp->fsm.link) || !ccp->fsm.bundle->ncp.mp.active ?
787         PROTO_COMPD : PROTO_ICOMPD;
788}
789
790int
791ccp_SetOpenMode(struct ccp *ccp)
792{
793  int f;
794
795  for (f = 0; f < CCP_NEG_TOTAL; f++)
796    if (IsEnabled(ccp->cfg.neg[f])) {
797      ccp->fsm.open_mode = 0;
798      return 1;
799    }
800
801  ccp->fsm.open_mode = OPEN_PASSIVE;	/* Go straight to ST_STOPPED ? */
802
803  for (f = 0; f < CCP_NEG_TOTAL; f++)
804    if (IsAccepted(ccp->cfg.neg[f]))
805      return 1;
806
807  return 0;				/* No CCP at all */
808}
809
810int
811ccp_DefaultUsable(struct fsm *fp __unused)
812{
813  return 1;
814}
815
816int
817ccp_DefaultRequired(struct fsm *fp __unused)
818{
819  return 0;
820}
821
822struct layer ccplayer = { LAYER_CCP, "ccp", ccp_LayerPush, ccp_LayerPull };
823