1/*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3 *
4 * Copyright (c) 1996 - 2001 Brian Somers <brian@Awfulhak.org>
5 *          based on work by Toshiharu OHNO <tony-o@iij.ad.jp>
6 *                           Internet Initiative Japan, Inc (IIJ)
7 * All rights reserved.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 *    notice, this list of conditions and the following disclaimer in the
16 *    documentation and/or other materials provided with the distribution.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28 * SUCH DAMAGE.
29 *
30 * $FreeBSD$
31 */
32
33#include <sys/param.h>
34#include <netinet/in.h>
35#include <netinet/in_systm.h>
36#include <netinet/ip.h>
37#include <sys/socket.h>
38#include <sys/un.h>
39
40#include <stdarg.h>
41#include <stdio.h>
42#include <stdlib.h>
43#include <string.h>	/* memcpy() on some archs */
44#include <termios.h>
45
46#include "layer.h"
47#include "defs.h"
48#include "command.h"
49#include "mbuf.h"
50#include "log.h"
51#include "timer.h"
52#include "fsm.h"
53#include "proto.h"
54#include "pred.h"
55#include "deflate.h"
56#include "throughput.h"
57#include "iplist.h"
58#include "slcompress.h"
59#include "lqr.h"
60#include "hdlc.h"
61#include "lcp.h"
62#include "ccp.h"
63#include "ncpaddr.h"
64#include "ipcp.h"
65#include "filter.h"
66#include "descriptor.h"
67#include "prompt.h"
68#include "link.h"
69#include "mp.h"
70#include "async.h"
71#include "physical.h"
72#ifndef NORADIUS
73#include "radius.h"
74#endif
75#ifndef NODES
76#include "mppe.h"
77#endif
78#include "ipv6cp.h"
79#include "ncp.h"
80#include "bundle.h"
81
82static void CcpSendConfigReq(struct fsm *);
83static void CcpSentTerminateReq(struct fsm *);
84static void CcpSendTerminateAck(struct fsm *, u_char);
85static void CcpDecodeConfig(struct fsm *, u_char *, u_char *, int,
86                            struct fsm_decode *);
87static void CcpLayerStart(struct fsm *);
88static void CcpLayerFinish(struct fsm *);
89static int CcpLayerUp(struct fsm *);
90static void CcpLayerDown(struct fsm *);
91static void CcpInitRestartCounter(struct fsm *, int);
92static int CcpRecvResetReq(struct fsm *);
93static void CcpRecvResetAck(struct fsm *, u_char);
94
95static struct fsm_callbacks ccp_Callbacks = {
96  CcpLayerUp,
97  CcpLayerDown,
98  CcpLayerStart,
99  CcpLayerFinish,
100  CcpInitRestartCounter,
101  CcpSendConfigReq,
102  CcpSentTerminateReq,
103  CcpSendTerminateAck,
104  CcpDecodeConfig,
105  CcpRecvResetReq,
106  CcpRecvResetAck
107};
108
109static const char * const ccp_TimerNames[] =
110  {"CCP restart", "CCP openmode", "CCP stopped"};
111
112static const char *
113protoname(int proto)
114{
115  static char const * const cftypes[] = {
116    /* Check out the latest ``Compression Control Protocol'' rfc (1962) */
117    "OUI",		/* 0: OUI */
118    "PRED1",		/* 1: Predictor type 1 */
119    "PRED2",		/* 2: Predictor type 2 */
120    "PUDDLE",		/* 3: Puddle Jumber */
121    NULL, NULL, NULL, NULL, NULL, NULL,
122    NULL, NULL, NULL, NULL, NULL, NULL,
123    "HWPPC",		/* 16: Hewlett-Packard PPC */
124    "STAC",		/* 17: Stac Electronics LZS (rfc1974) */
125    "MPPE",		/* 18: Microsoft PPC (rfc2118) and */
126			/*     Microsoft PPE (draft-ietf-pppext-mppe) */
127    "GAND",		/* 19: Gandalf FZA (rfc1993) */
128    "V42BIS",		/* 20: ARG->DATA.42bis compression */
129    "BSD",		/* 21: BSD LZW Compress */
130    NULL,
131    "LZS-DCP",		/* 23: LZS-DCP Compression Protocol (rfc1967) */
132    "MAGNALINK/DEFLATE",/* 24: Magnalink Variable Resource (rfc1975) */
133			/* 24: Deflate (according to pppd-2.3.*) */
134    "DCE",		/* 25: Data Circuit-Terminating Equip (rfc1976) */
135    "DEFLATE",		/* 26: Deflate (rfc1979) */
136  };
137
138  if (proto < 0 || (unsigned)proto > sizeof cftypes / sizeof *cftypes ||
139      cftypes[proto] == NULL) {
140    if (proto == -1)
141      return "none";
142    return HexStr(proto, NULL, 0);
143  }
144
145  return cftypes[proto];
146}
147
148/* We support these algorithms, and Req them in the given order */
149static const struct ccp_algorithm * const algorithm[] = {
150  &DeflateAlgorithm,
151  &Pred1Algorithm,
152  &PppdDeflateAlgorithm
153#ifndef NODES
154  , &MPPEAlgorithm
155#endif
156};
157
158#define NALGORITHMS (sizeof algorithm/sizeof algorithm[0])
159
160int
161ccp_ReportStatus(struct cmdargs const *arg)
162{
163  struct ccp_opt **o;
164  struct link *l;
165  struct ccp *ccp;
166  int f;
167
168  l = command_ChooseLink(arg);
169  ccp = &l->ccp;
170
171  prompt_Printf(arg->prompt, "%s: %s [%s]\n", l->name, ccp->fsm.name,
172                State2Nam(ccp->fsm.state));
173  if (ccp->fsm.state == ST_OPENED) {
174    prompt_Printf(arg->prompt, " My protocol = %s, His protocol = %s\n",
175                  protoname(ccp->my_proto), protoname(ccp->his_proto));
176    prompt_Printf(arg->prompt, " Output: %ld --> %ld,  Input: %ld --> %ld\n",
177                  ccp->uncompout, ccp->compout,
178                  ccp->compin, ccp->uncompin);
179  }
180
181  if (ccp->in.algorithm != -1)
182    prompt_Printf(arg->prompt, "\n Input Options:  %s\n",
183                  (*algorithm[ccp->in.algorithm]->Disp)(&ccp->in.opt));
184
185  if (ccp->out.algorithm != -1) {
186    o = &ccp->out.opt;
187    for (f = 0; f < ccp->out.algorithm; f++)
188      if (IsEnabled(ccp->cfg.neg[algorithm[f]->Neg]))
189        o = &(*o)->next;
190    prompt_Printf(arg->prompt, " Output Options: %s\n",
191                  (*algorithm[ccp->out.algorithm]->Disp)(&(*o)->val));
192  }
193
194  prompt_Printf(arg->prompt, "\n Defaults: ");
195  prompt_Printf(arg->prompt, "FSM retry = %us, max %u Config"
196                " REQ%s, %u Term REQ%s\n", ccp->cfg.fsm.timeout,
197                ccp->cfg.fsm.maxreq, ccp->cfg.fsm.maxreq == 1 ? "" : "s",
198                ccp->cfg.fsm.maxtrm, ccp->cfg.fsm.maxtrm == 1 ? "" : "s");
199  prompt_Printf(arg->prompt, "           deflate windows: ");
200  prompt_Printf(arg->prompt, "incoming = %d, ", ccp->cfg.deflate.in.winsize);
201  prompt_Printf(arg->prompt, "outgoing = %d\n", ccp->cfg.deflate.out.winsize);
202#ifndef NODES
203  prompt_Printf(arg->prompt, "           MPPE: ");
204  if (ccp->cfg.mppe.keybits)
205    prompt_Printf(arg->prompt, "%d bits, ", ccp->cfg.mppe.keybits);
206  else
207    prompt_Printf(arg->prompt, "any bits, ");
208  switch (ccp->cfg.mppe.state) {
209  case MPPE_STATEFUL:
210    prompt_Printf(arg->prompt, "stateful");
211    break;
212  case MPPE_STATELESS:
213    prompt_Printf(arg->prompt, "stateless");
214    break;
215  case MPPE_ANYSTATE:
216    prompt_Printf(arg->prompt, "any state");
217    break;
218  }
219  prompt_Printf(arg->prompt, "%s\n",
220                ccp->cfg.mppe.required ? ", required" : "");
221#endif
222
223  prompt_Printf(arg->prompt, "\n           DEFLATE:    %s\n",
224                command_ShowNegval(ccp->cfg.neg[CCP_NEG_DEFLATE]));
225  prompt_Printf(arg->prompt, "           PREDICTOR1: %s\n",
226                command_ShowNegval(ccp->cfg.neg[CCP_NEG_PRED1]));
227  prompt_Printf(arg->prompt, "           DEFLATE24:  %s\n",
228                command_ShowNegval(ccp->cfg.neg[CCP_NEG_DEFLATE24]));
229#ifndef NODES
230  prompt_Printf(arg->prompt, "           MPPE:       %s\n",
231                command_ShowNegval(ccp->cfg.neg[CCP_NEG_MPPE]));
232#endif
233  return 0;
234}
235
236void
237ccp_SetupCallbacks(struct ccp *ccp)
238{
239  ccp->fsm.fn = &ccp_Callbacks;
240  ccp->fsm.FsmTimer.name = ccp_TimerNames[0];
241  ccp->fsm.OpenTimer.name = ccp_TimerNames[1];
242  ccp->fsm.StoppedTimer.name = ccp_TimerNames[2];
243}
244
245void
246ccp_Init(struct ccp *ccp, struct bundle *bundle, struct link *l,
247         const struct fsm_parent *parent)
248{
249  /* Initialise ourselves */
250
251  fsm_Init(&ccp->fsm, "CCP", PROTO_CCP, 1, CCP_MAXCODE, LogCCP,
252           bundle, l, parent, &ccp_Callbacks, ccp_TimerNames);
253
254  ccp->cfg.deflate.in.winsize = 0;
255  ccp->cfg.deflate.out.winsize = 15;
256  ccp->cfg.fsm.timeout = DEF_FSMRETRY;
257  ccp->cfg.fsm.maxreq = DEF_FSMTRIES;
258  ccp->cfg.fsm.maxtrm = DEF_FSMTRIES;
259  ccp->cfg.neg[CCP_NEG_DEFLATE] = NEG_ENABLED|NEG_ACCEPTED;
260  ccp->cfg.neg[CCP_NEG_PRED1] = NEG_ENABLED|NEG_ACCEPTED;
261  ccp->cfg.neg[CCP_NEG_DEFLATE24] = 0;
262#ifndef NODES
263  ccp->cfg.mppe.keybits = 0;
264  ccp->cfg.mppe.state = MPPE_ANYSTATE;
265  ccp->cfg.mppe.required = 0;
266  ccp->cfg.neg[CCP_NEG_MPPE] = NEG_ENABLED|NEG_ACCEPTED;
267#endif
268
269  ccp_Setup(ccp);
270}
271
272void
273ccp_Setup(struct ccp *ccp)
274{
275  /* Set ourselves up for a startup */
276  ccp->fsm.open_mode = 0;
277  ccp->his_proto = ccp->my_proto = -1;
278  ccp->reset_sent = ccp->last_reset = -1;
279  ccp->in.algorithm = ccp->out.algorithm = -1;
280  ccp->in.state = ccp->out.state = NULL;
281  ccp->in.opt.hdr.id = -1;
282  ccp->out.opt = NULL;
283  ccp->his_reject = ccp->my_reject = 0;
284  ccp->uncompout = ccp->compout = 0;
285  ccp->uncompin = ccp->compin = 0;
286}
287
288/*
289 * Is ccp *REQUIRED* ?
290 * We ask each of the configured ccp protocols if they're required and
291 * return TRUE if they are.
292 *
293 * It's not possible for the peer to reject a required ccp protocol
294 * without our state machine bringing the supporting lcp layer down.
295 *
296 * If ccp is required but not open, the NCP layer should not push
297 * any data into the link.
298 */
299int
300ccp_Required(struct ccp *ccp)
301{
302  unsigned f;
303
304  for (f = 0; f < NALGORITHMS; f++)
305    if (IsEnabled(ccp->cfg.neg[algorithm[f]->Neg]) &&
306        (*algorithm[f]->Required)(&ccp->fsm))
307      return 1;
308
309  return 0;
310}
311
312/*
313 * Report whether it's possible to increase a packet's size after
314 * compression (and by how much).
315 */
316int
317ccp_MTUOverhead(struct ccp *ccp)
318{
319  if (ccp->fsm.state == ST_OPENED && ccp->out.algorithm >= 0)
320    return algorithm[ccp->out.algorithm]->o.MTUOverhead;
321
322  return 0;
323}
324
325static void
326CcpInitRestartCounter(struct fsm *fp, int what)
327{
328  /* Set fsm timer load */
329  struct ccp *ccp = fsm2ccp(fp);
330
331  fp->FsmTimer.load = ccp->cfg.fsm.timeout * SECTICKS;
332  switch (what) {
333    case FSM_REQ_TIMER:
334      fp->restart = ccp->cfg.fsm.maxreq;
335      break;
336    case FSM_TRM_TIMER:
337      fp->restart = ccp->cfg.fsm.maxtrm;
338      break;
339    default:
340      fp->restart = 1;
341      break;
342  }
343}
344
345static void
346CcpSendConfigReq(struct fsm *fp)
347{
348  /* Send config REQ please */
349  struct ccp *ccp = fsm2ccp(fp);
350  struct ccp_opt **o;
351  u_char *cp, buff[100];
352  unsigned f;
353  int alloc;
354
355  cp = buff;
356  o = &ccp->out.opt;
357  alloc = ccp->his_reject == 0 && ccp->out.opt == NULL;
358  ccp->my_proto = -1;
359  ccp->out.algorithm = -1;
360  for (f = 0; f < NALGORITHMS; f++)
361    if (IsEnabled(ccp->cfg.neg[algorithm[f]->Neg]) &&
362        !REJECTED(ccp, algorithm[f]->id) &&
363        (*algorithm[f]->Usable)(fp)) {
364
365      if (!alloc)
366        for (o = &ccp->out.opt; *o != NULL; o = &(*o)->next)
367          if ((*o)->val.hdr.id == algorithm[f]->id && (*o)->algorithm == (int)f)
368            break;
369
370      if (alloc || *o == NULL) {
371        if ((*o = (struct ccp_opt *)malloc(sizeof(struct ccp_opt))) == NULL) {
372	  log_Printf(LogERROR, "%s: Not enough memory for CCP REQ !\n",
373		     fp->link->name);
374	  break;
375	}
376        (*o)->val.hdr.id = algorithm[f]->id;
377        (*o)->val.hdr.len = 2;
378        (*o)->next = NULL;
379        (*o)->algorithm = f;
380        (*algorithm[f]->o.OptInit)(fp->bundle, &(*o)->val, &ccp->cfg);
381      }
382
383      if (cp + (*o)->val.hdr.len > buff + sizeof buff) {
384        log_Printf(LogERROR, "%s: CCP REQ buffer overrun !\n", fp->link->name);
385        break;
386      }
387      memcpy(cp, &(*o)->val, (*o)->val.hdr.len);
388      cp += (*o)->val.hdr.len;
389
390      ccp->my_proto = (*o)->val.hdr.id;
391      ccp->out.algorithm = f;
392
393      if (alloc)
394        o = &(*o)->next;
395    }
396
397  fsm_Output(fp, CODE_CONFIGREQ, fp->reqid, buff, cp - buff, MB_CCPOUT);
398}
399
400void
401ccp_SendResetReq(struct fsm *fp)
402{
403  /* We can't read our input - ask peer to reset */
404  struct ccp *ccp = fsm2ccp(fp);
405
406  ccp->reset_sent = fp->reqid;
407  ccp->last_reset = -1;
408  fsm_Output(fp, CODE_RESETREQ, fp->reqid, NULL, 0, MB_CCPOUT);
409}
410
411static void
412CcpSentTerminateReq(struct fsm *fp __unused)
413{
414  /* Term REQ just sent by FSM */
415}
416
417static void
418CcpSendTerminateAck(struct fsm *fp, u_char id)
419{
420  /* Send Term ACK please */
421  fsm_Output(fp, CODE_TERMACK, id, NULL, 0, MB_CCPOUT);
422}
423
424static int
425CcpRecvResetReq(struct fsm *fp)
426{
427  /* Got a reset REQ, reset outgoing dictionary */
428  struct ccp *ccp = fsm2ccp(fp);
429  if (ccp->out.state == NULL)
430    return 1;
431  return (*algorithm[ccp->out.algorithm]->o.Reset)(ccp->out.state);
432}
433
434static void
435CcpLayerStart(struct fsm *fp)
436{
437  /* We're about to start up ! */
438  struct ccp *ccp = fsm2ccp(fp);
439
440  log_Printf(LogCCP, "%s: LayerStart.\n", fp->link->name);
441  fp->more.reqs = fp->more.naks = fp->more.rejs = ccp->cfg.fsm.maxreq * 3;
442}
443
444static void
445CcpLayerDown(struct fsm *fp)
446{
447  /* About to come down */
448  struct ccp *ccp = fsm2ccp(fp);
449  struct ccp_opt *next;
450
451  log_Printf(LogCCP, "%s: LayerDown.\n", fp->link->name);
452  if (ccp->in.state != NULL) {
453    (*algorithm[ccp->in.algorithm]->i.Term)(ccp->in.state);
454    ccp->in.state = NULL;
455    ccp->in.algorithm = -1;
456  }
457  if (ccp->out.state != NULL) {
458    (*algorithm[ccp->out.algorithm]->o.Term)(ccp->out.state);
459    ccp->out.state = NULL;
460    ccp->out.algorithm = -1;
461  }
462  ccp->his_reject = ccp->my_reject = 0;
463
464  while (ccp->out.opt) {
465    next = ccp->out.opt->next;
466    free(ccp->out.opt);
467    ccp->out.opt = next;
468  }
469  ccp_Setup(ccp);
470}
471
472static void
473CcpLayerFinish(struct fsm *fp)
474{
475  /* We're now down */
476  struct ccp *ccp = fsm2ccp(fp);
477  struct ccp_opt *next;
478
479  log_Printf(LogCCP, "%s: LayerFinish.\n", fp->link->name);
480
481  /*
482   * Nuke options that may be left over from sending a REQ but never
483   * coming up.
484   */
485  while (ccp->out.opt) {
486    next = ccp->out.opt->next;
487    free(ccp->out.opt);
488    ccp->out.opt = next;
489  }
490
491  if (ccp_Required(ccp)) {
492    if (fp->link->lcp.fsm.state == ST_OPENED)
493      log_Printf(LogLCP, "%s: Closing due to CCP completion\n", fp->link->name);
494    fsm_Close(&fp->link->lcp.fsm);
495  }
496}
497
498/*  Called when CCP has reached the OPEN state */
499static int
500CcpLayerUp(struct fsm *fp)
501{
502  /* We're now up */
503  struct ccp *ccp = fsm2ccp(fp);
504  struct ccp_opt **o;
505  unsigned f, fail;
506
507  for (f = fail = 0; f < NALGORITHMS; f++)
508    if (IsEnabled(ccp->cfg.neg[algorithm[f]->Neg]) &&
509        (*algorithm[f]->Required)(&ccp->fsm) &&
510        (ccp->in.algorithm != (int)f || ccp->out.algorithm != (int)f)) {
511      /* Blow it all away - we haven't negotiated a required algorithm */
512      log_Printf(LogWARN, "%s: Failed to negotiate (required) %s\n",
513                 fp->link->name, protoname(algorithm[f]->id));
514      fail = 1;
515    }
516
517  if (fail) {
518    ccp->his_proto = ccp->my_proto = -1;
519    fsm_Close(fp);
520    fsm_Close(&fp->link->lcp.fsm);
521    return 0;
522  }
523
524  log_Printf(LogCCP, "%s: LayerUp.\n", fp->link->name);
525
526  if (ccp->in.state == NULL && ccp->in.algorithm >= 0 &&
527      ccp->in.algorithm < (int)NALGORITHMS) {
528    ccp->in.state = (*algorithm[ccp->in.algorithm]->i.Init)
529      (fp->bundle, &ccp->in.opt);
530    if (ccp->in.state == NULL) {
531      log_Printf(LogERROR, "%s: %s (in) initialisation failure\n",
532                fp->link->name, protoname(ccp->his_proto));
533      ccp->his_proto = ccp->my_proto = -1;
534      fsm_Close(fp);
535      return 0;
536    }
537  }
538
539  o = &ccp->out.opt;
540  if (ccp->out.algorithm > 0)
541    for (f = 0; f < (unsigned)ccp->out.algorithm; f++)
542      if (IsEnabled(ccp->cfg.neg[algorithm[f]->Neg]))
543	o = &(*o)->next;
544
545  if (ccp->out.state == NULL && ccp->out.algorithm >= 0 &&
546      ccp->out.algorithm < (int)NALGORITHMS) {
547    ccp->out.state = (*algorithm[ccp->out.algorithm]->o.Init)
548      (fp->bundle, &(*o)->val);
549    if (ccp->out.state == NULL) {
550      log_Printf(LogERROR, "%s: %s (out) initialisation failure\n",
551                fp->link->name, protoname(ccp->my_proto));
552      ccp->his_proto = ccp->my_proto = -1;
553      fsm_Close(fp);
554      return 0;
555    }
556  }
557
558  fp->more.reqs = fp->more.naks = fp->more.rejs = ccp->cfg.fsm.maxreq * 3;
559
560  log_Printf(LogCCP, "%s: Out = %s[%d], In = %s[%d]\n",
561            fp->link->name, protoname(ccp->my_proto), ccp->my_proto,
562            protoname(ccp->his_proto), ccp->his_proto);
563
564  return 1;
565}
566
567static void
568CcpDecodeConfig(struct fsm *fp, u_char *cp, u_char *end, int mode_type,
569                struct fsm_decode *dec)
570{
571  /* Deal with incoming data */
572  struct ccp *ccp = fsm2ccp(fp);
573  int f;
574  const char *disp;
575  struct fsm_opt *opt;
576
577  if (mode_type == MODE_REQ)
578    ccp->in.algorithm = -1;	/* In case we've received two REQs in a row */
579
580  while (end >= cp + sizeof(opt->hdr)) {
581    if ((opt = fsm_readopt(&cp)) == NULL)
582      break;
583
584    for (f = NALGORITHMS-1; f > -1; f--)
585      if (algorithm[f]->id == opt->hdr.id)
586        break;
587
588    disp = f == -1 ? "" : (*algorithm[f]->Disp)(opt);
589    if (disp == NULL)
590      disp = "";
591
592    log_Printf(LogCCP, " %s[%d] %s\n", protoname(opt->hdr.id),
593               opt->hdr.len, disp);
594
595    if (f == -1) {
596      /* Don't understand that :-( */
597      if (mode_type == MODE_REQ) {
598        ccp->my_reject |= (1 << opt->hdr.id);
599        fsm_rej(dec, opt);
600      }
601    } else {
602      struct ccp_opt *o;
603
604      switch (mode_type) {
605      case MODE_REQ:
606        if (IsAccepted(ccp->cfg.neg[algorithm[f]->Neg]) &&
607            (*algorithm[f]->Usable)(fp) &&
608            ccp->in.algorithm == -1) {
609          memcpy(&ccp->in.opt, opt, opt->hdr.len);
610          switch ((*algorithm[f]->i.Set)(fp->bundle, &ccp->in.opt, &ccp->cfg)) {
611          case MODE_REJ:
612            fsm_rej(dec, &ccp->in.opt);
613            break;
614          case MODE_NAK:
615            fsm_nak(dec, &ccp->in.opt);
616            break;
617          case MODE_ACK:
618            fsm_ack(dec, &ccp->in.opt);
619            ccp->his_proto = opt->hdr.id;
620            ccp->in.algorithm = (int)f;		/* This one'll do :-) */
621            break;
622          }
623        } else {
624          fsm_rej(dec, opt);
625        }
626        break;
627      case MODE_NAK:
628        for (o = ccp->out.opt; o != NULL; o = o->next)
629          if (o->val.hdr.id == opt->hdr.id)
630            break;
631        if (o == NULL)
632          log_Printf(LogCCP, "%s: Warning: Ignoring peer NAK of unsent"
633                     " option\n", fp->link->name);
634        else {
635          memcpy(&o->val, opt, opt->hdr.len);
636          if ((*algorithm[f]->o.Set)(fp->bundle, &o->val, &ccp->cfg) ==
637              MODE_ACK)
638            ccp->my_proto = algorithm[f]->id;
639          else {
640            ccp->his_reject |= (1 << opt->hdr.id);
641            ccp->my_proto = -1;
642            if (algorithm[f]->Required(fp)) {
643              log_Printf(LogWARN, "%s: Cannot understand peers (required)"
644                         " %s negotiation\n", fp->link->name,
645                         protoname(algorithm[f]->id));
646              fsm_Close(&fp->link->lcp.fsm);
647            }
648          }
649        }
650        break;
651      case MODE_REJ:
652        ccp->his_reject |= (1 << opt->hdr.id);
653        ccp->my_proto = -1;
654        if (algorithm[f]->Required(fp)) {
655          log_Printf(LogWARN, "%s: Peer rejected (required) %s negotiation\n",
656                     fp->link->name, protoname(algorithm[f]->id));
657          fsm_Close(&fp->link->lcp.fsm);
658        }
659        break;
660      }
661    }
662  }
663
664  if (mode_type != MODE_NOP) {
665    fsm_opt_normalise(dec);
666    if (dec->rejend != dec->rej || dec->nakend != dec->nak) {
667      if (ccp->in.state == NULL) {
668        ccp->his_proto = -1;
669        ccp->in.algorithm = -1;
670      }
671    }
672  }
673}
674
675extern struct mbuf *
676ccp_Input(struct bundle *bundle, struct link *l, struct mbuf *bp)
677{
678  /* Got PROTO_CCP from link */
679  m_settype(bp, MB_CCPIN);
680  if (bundle_Phase(bundle) == PHASE_NETWORK)
681    fsm_Input(&l->ccp.fsm, bp);
682  else {
683    if (bundle_Phase(bundle) < PHASE_NETWORK)
684      log_Printf(LogCCP, "%s: Error: Unexpected CCP in phase %s (ignored)\n",
685                 l->ccp.fsm.link->name, bundle_PhaseName(bundle));
686    m_freem(bp);
687  }
688  return NULL;
689}
690
691static void
692CcpRecvResetAck(struct fsm *fp, u_char id)
693{
694  /* Got a reset ACK, reset incoming dictionary */
695  struct ccp *ccp = fsm2ccp(fp);
696
697  if (ccp->reset_sent != -1) {
698    if (id != ccp->reset_sent) {
699      log_Printf(LogCCP, "%s: Incorrect ResetAck (id %d, not %d)"
700                " ignored\n", fp->link->name, id, ccp->reset_sent);
701      return;
702    }
703    /* Whaddaya know - a correct reset ack */
704  } else if (id == ccp->last_reset)
705    log_Printf(LogCCP, "%s: Duplicate ResetAck (resetting again)\n",
706               fp->link->name);
707  else {
708    log_Printf(LogCCP, "%s: Unexpected ResetAck (id %d) ignored\n",
709               fp->link->name, id);
710    return;
711  }
712
713  ccp->last_reset = ccp->reset_sent;
714  ccp->reset_sent = -1;
715  if (ccp->in.state != NULL)
716    (*algorithm[ccp->in.algorithm]->i.Reset)(ccp->in.state);
717}
718
719static struct mbuf *
720ccp_LayerPush(struct bundle *b __unused, struct link *l, struct mbuf *bp,
721              int pri, u_short *proto)
722{
723  if (PROTO_COMPRESSIBLE(*proto)) {
724    if (l->ccp.fsm.state != ST_OPENED) {
725      if (ccp_Required(&l->ccp)) {
726        /* The NCP layer shouldn't have let this happen ! */
727        log_Printf(LogERROR, "%s: Unexpected attempt to use an unopened and"
728                   " required CCP layer\n", l->name);
729        m_freem(bp);
730        bp = NULL;
731      }
732    } else if (l->ccp.out.state != NULL) {
733      bp = (*algorithm[l->ccp.out.algorithm]->o.Write)
734             (l->ccp.out.state, &l->ccp, l, pri, proto, bp);
735      switch (*proto) {
736        case PROTO_ICOMPD:
737          m_settype(bp, MB_ICOMPDOUT);
738          break;
739        case PROTO_COMPD:
740          m_settype(bp, MB_COMPDOUT);
741          break;
742      }
743    }
744  }
745
746  return bp;
747}
748
749static struct mbuf *
750ccp_LayerPull(struct bundle *b __unused, struct link *l, struct mbuf *bp,
751	      u_short *proto)
752{
753  /*
754   * If proto isn't PROTO_[I]COMPD, we still want to pass it to the
755   * decompression routines so that the dictionary's updated
756   */
757  if (l->ccp.fsm.state == ST_OPENED) {
758    if (*proto == PROTO_COMPD || *proto == PROTO_ICOMPD) {
759      /* Decompress incoming data */
760      if (l->ccp.reset_sent != -1)
761        /* Send another REQ and put the packet in the bit bucket */
762        fsm_Output(&l->ccp.fsm, CODE_RESETREQ, l->ccp.reset_sent, NULL, 0,
763                   MB_CCPOUT);
764      else if (l->ccp.in.state != NULL) {
765        bp = (*algorithm[l->ccp.in.algorithm]->i.Read)
766               (l->ccp.in.state, &l->ccp, proto, bp);
767        switch (*proto) {
768          case PROTO_ICOMPD:
769            m_settype(bp, MB_ICOMPDIN);
770            break;
771          case PROTO_COMPD:
772            m_settype(bp, MB_COMPDIN);
773            break;
774        }
775        return bp;
776      }
777      m_freem(bp);
778      bp = NULL;
779    } else if (PROTO_COMPRESSIBLE(*proto) && l->ccp.in.state != NULL) {
780      /* Add incoming Network Layer traffic to our dictionary */
781      (*algorithm[l->ccp.in.algorithm]->i.DictSetup)
782        (l->ccp.in.state, &l->ccp, *proto, bp);
783    }
784  }
785
786  return bp;
787}
788
789u_short
790ccp_Proto(struct ccp *ccp)
791{
792  return !link2physical(ccp->fsm.link) || !ccp->fsm.bundle->ncp.mp.active ?
793         PROTO_COMPD : PROTO_ICOMPD;
794}
795
796int
797ccp_SetOpenMode(struct ccp *ccp)
798{
799  int f;
800
801  for (f = 0; f < CCP_NEG_TOTAL; f++)
802    if (IsEnabled(ccp->cfg.neg[f])) {
803      ccp->fsm.open_mode = 0;
804      return 1;
805    }
806
807  ccp->fsm.open_mode = OPEN_PASSIVE;	/* Go straight to ST_STOPPED ? */
808
809  for (f = 0; f < CCP_NEG_TOTAL; f++)
810    if (IsAccepted(ccp->cfg.neg[f]))
811      return 1;
812
813  return 0;				/* No CCP at all */
814}
815
816int
817ccp_DefaultUsable(struct fsm *fp __unused)
818{
819  return 1;
820}
821
822int
823ccp_DefaultRequired(struct fsm *fp __unused)
824{
825  return 0;
826}
827
828struct layer ccplayer = { LAYER_CCP, "ccp", ccp_LayerPush, ccp_LayerPull };
829