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      1 /*-
      2  * Copyright (c) 1996 - 2001 Brian Somers <brian (at) Awfulhak.org>
      3  *          based on work by Toshiharu OHNO <tony-o (at) 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: src/usr.sbin/ppp/ccp.c,v 1.78.26.1 2010/12/21 17:10:29 kensmith Exp $
     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 
     80 static void CcpSendConfigReq(struct fsm *);
     81 static void CcpSentTerminateReq(struct fsm *);
     82 static void CcpSendTerminateAck(struct fsm *, u_char);
     83 static void CcpDecodeConfig(struct fsm *, u_char *, u_char *, int,
     84                             struct fsm_decode *);
     85 static void CcpLayerStart(struct fsm *);
     86 static void CcpLayerFinish(struct fsm *);
     87 static int CcpLayerUp(struct fsm *);
     88 static void CcpLayerDown(struct fsm *);
     89 static void CcpInitRestartCounter(struct fsm *, int);
     90 static int CcpRecvResetReq(struct fsm *);
     91 static void CcpRecvResetAck(struct fsm *, u_char);
     92 
     93 static 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 
    107 static const char * const ccp_TimerNames[] =
    108   {"CCP restart", "CCP openmode", "CCP stopped"};
    109 
    110 static const char *
    111 protoname(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 */
    147 static 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 
    158 int
    159 ccp_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 
    234 void
    235 ccp_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 
    243 void
    244 ccp_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 
    270 void
    271 ccp_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  */
    297 int
    298 ccp_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  */
    314 int
    315 ccp_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 
    323 static void
    324 CcpInitRestartCounter(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 
    343 static void
    344 CcpSendConfigReq(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         if ((*o = (struct ccp_opt *)malloc(sizeof(struct ccp_opt))) == NULL) {
    370 	  log_Printf(LogERROR, "%s: Not enough memory for CCP REQ !\n",
    371 		     fp->link->name);
    372 	  break;
    373 	}
    374         (*o)->val.hdr.id = algorithm[f]->id;
    375         (*o)->val.hdr.len = 2;
    376         (*o)->next = NULL;
    377         (*o)->algorithm = f;
    378         (*algorithm[f]->o.OptInit)(fp->bundle, &(*o)->val, &ccp->cfg);
    379       }
    380 
    381       if (cp + (*o)->val.hdr.len > buff + sizeof buff) {
    382         log_Printf(LogERROR, "%s: CCP REQ buffer overrun !\n", fp->link->name);
    383         break;
    384       }
    385       memcpy(cp, &(*o)->val, (*o)->val.hdr.len);
    386       cp += (*o)->val.hdr.len;
    387 
    388       ccp->my_proto = (*o)->val.hdr.id;
    389       ccp->out.algorithm = f;
    390 
    391       if (alloc)
    392         o = &(*o)->next;
    393     }
    394 
    395   fsm_Output(fp, CODE_CONFIGREQ, fp->reqid, buff, cp - buff, MB_CCPOUT);
    396 }
    397 
    398 void
    399 ccp_SendResetReq(struct fsm *fp)
    400 {
    401   /* We can't read our input - ask peer to reset */
    402   struct ccp *ccp = fsm2ccp(fp);
    403 
    404   ccp->reset_sent = fp->reqid;
    405   ccp->last_reset = -1;
    406   fsm_Output(fp, CODE_RESETREQ, fp->reqid, NULL, 0, MB_CCPOUT);
    407 }
    408 
    409 static void
    410 CcpSentTerminateReq(struct fsm *fp __unused)
    411 {
    412   /* Term REQ just sent by FSM */
    413 }
    414 
    415 static void
    416 CcpSendTerminateAck(struct fsm *fp, u_char id)
    417 {
    418   /* Send Term ACK please */
    419   fsm_Output(fp, CODE_TERMACK, id, NULL, 0, MB_CCPOUT);
    420 }
    421 
    422 static int
    423 CcpRecvResetReq(struct fsm *fp)
    424 {
    425   /* Got a reset REQ, reset outgoing dictionary */
    426   struct ccp *ccp = fsm2ccp(fp);
    427   if (ccp->out.state == NULL)
    428     return 1;
    429   return (*algorithm[ccp->out.algorithm]->o.Reset)(ccp->out.state);
    430 }
    431 
    432 static void
    433 CcpLayerStart(struct fsm *fp)
    434 {
    435   /* We're about to start up ! */
    436   struct ccp *ccp = fsm2ccp(fp);
    437 
    438   log_Printf(LogCCP, "%s: LayerStart.\n", fp->link->name);
    439   fp->more.reqs = fp->more.naks = fp->more.rejs = ccp->cfg.fsm.maxreq * 3;
    440 }
    441 
    442 static void
    443 CcpLayerDown(struct fsm *fp)
    444 {
    445   /* About to come down */
    446   struct ccp *ccp = fsm2ccp(fp);
    447   struct ccp_opt *next;
    448 
    449   log_Printf(LogCCP, "%s: LayerDown.\n", fp->link->name);
    450   if (ccp->in.state != NULL) {
    451     (*algorithm[ccp->in.algorithm]->i.Term)(ccp->in.state);
    452     ccp->in.state = NULL;
    453     ccp->in.algorithm = -1;
    454   }
    455   if (ccp->out.state != NULL) {
    456     (*algorithm[ccp->out.algorithm]->o.Term)(ccp->out.state);
    457     ccp->out.state = NULL;
    458     ccp->out.algorithm = -1;
    459   }
    460   ccp->his_reject = ccp->my_reject = 0;
    461 
    462   while (ccp->out.opt) {
    463     next = ccp->out.opt->next;
    464     free(ccp->out.opt);
    465     ccp->out.opt = next;
    466   }
    467   ccp_Setup(ccp);
    468 }
    469 
    470 static void
    471 CcpLayerFinish(struct fsm *fp)
    472 {
    473   /* We're now down */
    474   struct ccp *ccp = fsm2ccp(fp);
    475   struct ccp_opt *next;
    476 
    477   log_Printf(LogCCP, "%s: LayerFinish.\n", fp->link->name);
    478 
    479   /*
    480    * Nuke options that may be left over from sending a REQ but never
    481    * coming up.
    482    */
    483   while (ccp->out.opt) {
    484     next = ccp->out.opt->next;
    485     free(ccp->out.opt);
    486     ccp->out.opt = next;
    487   }
    488 
    489   if (ccp_Required(ccp)) {
    490     if (fp->link->lcp.fsm.state == ST_OPENED)
    491       log_Printf(LogLCP, "%s: Closing due to CCP completion\n", fp->link->name);
    492     fsm_Close(&fp->link->lcp.fsm);
    493   }
    494 }
    495 
    496 /*  Called when CCP has reached the OPEN state */
    497 static int
    498 CcpLayerUp(struct fsm *fp)
    499 {
    500   /* We're now up */
    501   struct ccp *ccp = fsm2ccp(fp);
    502   struct ccp_opt **o;
    503   unsigned f, fail;
    504 
    505   for (f = fail = 0; f < NALGORITHMS; f++)
    506     if (IsEnabled(ccp->cfg.neg[algorithm[f]->Neg]) &&
    507         (*algorithm[f]->Required)(&ccp->fsm) &&
    508         (ccp->in.algorithm != (int)f || ccp->out.algorithm != (int)f)) {
    509       /* Blow it all away - we haven't negotiated a required algorithm */
    510       log_Printf(LogWARN, "%s: Failed to negotiate (required) %s\n",
    511                  fp->link->name, protoname(algorithm[f]->id));
    512       fail = 1;
    513     }
    514 
    515   if (fail) {
    516     ccp->his_proto = ccp->my_proto = -1;
    517     fsm_Close(fp);
    518     fsm_Close(&fp->link->lcp.fsm);
    519     return 0;
    520   }
    521 
    522   log_Printf(LogCCP, "%s: LayerUp.\n", fp->link->name);
    523 
    524   if (ccp->in.state == NULL && ccp->in.algorithm >= 0 &&
    525       ccp->in.algorithm < (int)NALGORITHMS) {
    526     ccp->in.state = (*algorithm[ccp->in.algorithm]->i.Init)
    527       (fp->bundle, &ccp->in.opt);
    528     if (ccp->in.state == NULL) {
    529       log_Printf(LogERROR, "%s: %s (in) initialisation failure\n",
    530                 fp->link->name, protoname(ccp->his_proto));
    531       ccp->his_proto = ccp->my_proto = -1;
    532       fsm_Close(fp);
    533       return 0;
    534     }
    535   }
    536 
    537   o = &ccp->out.opt;
    538   if (ccp->out.algorithm > 0)
    539     for (f = 0; f < (unsigned)ccp->out.algorithm; f++)
    540       if (IsEnabled(ccp->cfg.neg[algorithm[f]->Neg]))
    541 	o = &(*o)->next;
    542 
    543   if (ccp->out.state == NULL && ccp->out.algorithm >= 0 &&
    544       ccp->out.algorithm < (int)NALGORITHMS) {
    545     ccp->out.state = (*algorithm[ccp->out.algorithm]->o.Init)
    546       (fp->bundle, &(*o)->val);
    547     if (ccp->out.state == NULL) {
    548       log_Printf(LogERROR, "%s: %s (out) initialisation failure\n",
    549                 fp->link->name, protoname(ccp->my_proto));
    550       ccp->his_proto = ccp->my_proto = -1;
    551       fsm_Close(fp);
    552       return 0;
    553     }
    554   }
    555 
    556   fp->more.reqs = fp->more.naks = fp->more.rejs = ccp->cfg.fsm.maxreq * 3;
    557 
    558   log_Printf(LogCCP, "%s: Out = %s[%d], In = %s[%d]\n",
    559             fp->link->name, protoname(ccp->my_proto), ccp->my_proto,
    560             protoname(ccp->his_proto), ccp->his_proto);
    561 
    562   return 1;
    563 }
    564 
    565 static void
    566 CcpDecodeConfig(struct fsm *fp, u_char *cp, u_char *end, int mode_type,
    567                 struct fsm_decode *dec)
    568 {
    569   /* Deal with incoming data */
    570   struct ccp *ccp = fsm2ccp(fp);
    571   int f;
    572   const char *disp;
    573   struct fsm_opt *opt;
    574 
    575   if (mode_type == MODE_REQ)
    576     ccp->in.algorithm = -1;	/* In case we've received two REQs in a row */
    577 
    578   while (end >= cp + sizeof(opt->hdr)) {
    579     if ((opt = fsm_readopt(&cp)) == NULL)
    580       break;
    581 
    582     for (f = NALGORITHMS-1; f > -1; f--)
    583       if (algorithm[f]->id == opt->hdr.id)
    584         break;
    585 
    586     disp = f == -1 ? "" : (*algorithm[f]->Disp)(opt);
    587     if (disp == NULL)
    588       disp = "";
    589 
    590     log_Printf(LogCCP, " %s[%d] %s\n", protoname(opt->hdr.id),
    591                opt->hdr.len, disp);
    592 
    593     if (f == -1) {
    594       /* Don't understand that :-( */
    595       if (mode_type == MODE_REQ) {
    596         ccp->my_reject |= (1 << opt->hdr.id);
    597         fsm_rej(dec, opt);
    598       }
    599     } else {
    600       struct ccp_opt *o;
    601 
    602       switch (mode_type) {
    603       case MODE_REQ:
    604         if (IsAccepted(ccp->cfg.neg[algorithm[f]->Neg]) &&
    605             (*algorithm[f]->Usable)(fp) &&
    606             ccp->in.algorithm == -1) {
    607           memcpy(&ccp->in.opt, opt, opt->hdr.len);
    608           switch ((*algorithm[f]->i.Set)(fp->bundle, &ccp->in.opt, &ccp->cfg)) {
    609           case MODE_REJ:
    610             fsm_rej(dec, &ccp->in.opt);
    611             break;
    612           case MODE_NAK:
    613             fsm_nak(dec, &ccp->in.opt);
    614             break;
    615           case MODE_ACK:
    616             fsm_ack(dec, &ccp->in.opt);
    617             ccp->his_proto = opt->hdr.id;
    618             ccp->in.algorithm = (int)f;		/* This one'll do :-) */
    619             break;
    620           }
    621         } else {
    622           fsm_rej(dec, opt);
    623         }
    624         break;
    625       case MODE_NAK:
    626         for (o = ccp->out.opt; o != NULL; o = o->next)
    627           if (o->val.hdr.id == opt->hdr.id)
    628             break;
    629         if (o == NULL)
    630           log_Printf(LogCCP, "%s: Warning: Ignoring peer NAK of unsent"
    631                      " option\n", fp->link->name);
    632         else {
    633           memcpy(&o->val, opt, opt->hdr.len);
    634           if ((*algorithm[f]->o.Set)(fp->bundle, &o->val, &ccp->cfg) ==
    635               MODE_ACK)
    636             ccp->my_proto = algorithm[f]->id;
    637           else {
    638             ccp->his_reject |= (1 << opt->hdr.id);
    639             ccp->my_proto = -1;
    640             if (algorithm[f]->Required(fp)) {
    641               log_Printf(LogWARN, "%s: Cannot understand peers (required)"
    642                          " %s negotiation\n", fp->link->name,
    643                          protoname(algorithm[f]->id));
    644               fsm_Close(&fp->link->lcp.fsm);
    645             }
    646           }
    647         }
    648         break;
    649       case MODE_REJ:
    650         ccp->his_reject |= (1 << opt->hdr.id);
    651         ccp->my_proto = -1;
    652         if (algorithm[f]->Required(fp)) {
    653           log_Printf(LogWARN, "%s: Peer rejected (required) %s negotiation\n",
    654                      fp->link->name, protoname(algorithm[f]->id));
    655           fsm_Close(&fp->link->lcp.fsm);
    656         }
    657         break;
    658       }
    659     }
    660   }
    661 
    662   if (mode_type != MODE_NOP) {
    663     fsm_opt_normalise(dec);
    664     if (dec->rejend != dec->rej || dec->nakend != dec->nak) {
    665       if (ccp->in.state == NULL) {
    666         ccp->his_proto = -1;
    667         ccp->in.algorithm = -1;
    668       }
    669     }
    670   }
    671 }
    672 
    673 extern struct mbuf *
    674 ccp_Input(struct bundle *bundle, struct link *l, struct mbuf *bp)
    675 {
    676   /* Got PROTO_CCP from link */
    677   m_settype(bp, MB_CCPIN);
    678   if (bundle_Phase(bundle) == PHASE_NETWORK)
    679     fsm_Input(&l->ccp.fsm, bp);
    680   else {
    681     if (bundle_Phase(bundle) < PHASE_NETWORK)
    682       log_Printf(LogCCP, "%s: Error: Unexpected CCP in phase %s (ignored)\n",
    683                  l->ccp.fsm.link->name, bundle_PhaseName(bundle));
    684     m_freem(bp);
    685   }
    686   return NULL;
    687 }
    688 
    689 static void
    690 CcpRecvResetAck(struct fsm *fp, u_char id)
    691 {
    692   /* Got a reset ACK, reset incoming dictionary */
    693   struct ccp *ccp = fsm2ccp(fp);
    694 
    695   if (ccp->reset_sent != -1) {
    696     if (id != ccp->reset_sent) {
    697       log_Printf(LogCCP, "%s: Incorrect ResetAck (id %d, not %d)"
    698                 " ignored\n", fp->link->name, id, ccp->reset_sent);
    699       return;
    700     }
    701     /* Whaddaya know - a correct reset ack */
    702   } else if (id == ccp->last_reset)
    703     log_Printf(LogCCP, "%s: Duplicate ResetAck (resetting again)\n",
    704                fp->link->name);
    705   else {
    706     log_Printf(LogCCP, "%s: Unexpected ResetAck (id %d) ignored\n",
    707                fp->link->name, id);
    708     return;
    709   }
    710 
    711   ccp->last_reset = ccp->reset_sent;
    712   ccp->reset_sent = -1;
    713   if (ccp->in.state != NULL)
    714     (*algorithm[ccp->in.algorithm]->i.Reset)(ccp->in.state);
    715 }
    716 
    717 static struct mbuf *
    718 ccp_LayerPush(struct bundle *b __unused, struct link *l, struct mbuf *bp,
    719               int pri, u_short *proto)
    720 {
    721   if (PROTO_COMPRESSIBLE(*proto)) {
    722     if (l->ccp.fsm.state != ST_OPENED) {
    723       if (ccp_Required(&l->ccp)) {
    724         /* The NCP layer shouldn't have let this happen ! */
    725         log_Printf(LogERROR, "%s: Unexpected attempt to use an unopened and"
    726                    " required CCP layer\n", l->name);
    727         m_freem(bp);
    728         bp = NULL;
    729       }
    730     } else if (l->ccp.out.state != NULL) {
    731       bp = (*algorithm[l->ccp.out.algorithm]->o.Write)
    732              (l->ccp.out.state, &l->ccp, l, pri, proto, bp);
    733       switch (*proto) {
    734         case PROTO_ICOMPD:
    735           m_settype(bp, MB_ICOMPDOUT);
    736           break;
    737         case PROTO_COMPD:
    738           m_settype(bp, MB_COMPDOUT);
    739           break;
    740       }
    741     }
    742   }
    743 
    744   return bp;
    745 }
    746 
    747 static struct mbuf *
    748 ccp_LayerPull(struct bundle *b __unused, struct link *l, struct mbuf *bp,
    749 	      u_short *proto)
    750 {
    751   /*
    752    * If proto isn't PROTO_[I]COMPD, we still want to pass it to the
    753    * decompression routines so that the dictionary's updated
    754    */
    755   if (l->ccp.fsm.state == ST_OPENED) {
    756     if (*proto == PROTO_COMPD || *proto == PROTO_ICOMPD) {
    757       /* Decompress incoming data */
    758       if (l->ccp.reset_sent != -1)
    759         /* Send another REQ and put the packet in the bit bucket */
    760         fsm_Output(&l->ccp.fsm, CODE_RESETREQ, l->ccp.reset_sent, NULL, 0,
    761                    MB_CCPOUT);
    762       else if (l->ccp.in.state != NULL) {
    763         bp = (*algorithm[l->ccp.in.algorithm]->i.Read)
    764                (l->ccp.in.state, &l->ccp, proto, bp);
    765         switch (*proto) {
    766           case PROTO_ICOMPD:
    767             m_settype(bp, MB_ICOMPDIN);
    768             break;
    769           case PROTO_COMPD:
    770             m_settype(bp, MB_COMPDIN);
    771             break;
    772         }
    773         return bp;
    774       }
    775       m_freem(bp);
    776       bp = NULL;
    777     } else if (PROTO_COMPRESSIBLE(*proto) && l->ccp.in.state != NULL) {
    778       /* Add incoming Network Layer traffic to our dictionary */
    779       (*algorithm[l->ccp.in.algorithm]->i.DictSetup)
    780         (l->ccp.in.state, &l->ccp, *proto, bp);
    781     }
    782   }
    783 
    784   return bp;
    785 }
    786 
    787 u_short
    788 ccp_Proto(struct ccp *ccp)
    789 {
    790   return !link2physical(ccp->fsm.link) || !ccp->fsm.bundle->ncp.mp.active ?
    791          PROTO_COMPD : PROTO_ICOMPD;
    792 }
    793 
    794 int
    795 ccp_SetOpenMode(struct ccp *ccp)
    796 {
    797   int f;
    798 
    799   for (f = 0; f < CCP_NEG_TOTAL; f++)
    800     if (IsEnabled(ccp->cfg.neg[f])) {
    801       ccp->fsm.open_mode = 0;
    802       return 1;
    803     }
    804 
    805   ccp->fsm.open_mode = OPEN_PASSIVE;	/* Go straight to ST_STOPPED ? */
    806 
    807   for (f = 0; f < CCP_NEG_TOTAL; f++)
    808     if (IsAccepted(ccp->cfg.neg[f]))
    809       return 1;
    810 
    811   return 0;				/* No CCP at all */
    812 }
    813 
    814 int
    815 ccp_DefaultUsable(struct fsm *fp __unused)
    816 {
    817   return 1;
    818 }
    819 
    820 int
    821 ccp_DefaultRequired(struct fsm *fp __unused)
    822 {
    823   return 0;
    824 }
    825 
    826 struct layer ccplayer = { LAYER_CCP, "ccp", ccp_LayerPush, ccp_LayerPull };
    827