lcp.c

00001 /*****************************************************************************
00002 * lcp.c - Network Link Control Protocol program file.
00003 *
00004 * Copyright (c) 2003 by Marc Boucher, Services Informatiques (MBSI) inc.
00005 * portions Copyright (c) 1997 by Global Election Systems Inc.
00006 *
00007 * The authors hereby grant permission to use, copy, modify, distribute,
00008 * and license this software and its documentation for any purpose, provided
00009 * that existing copyright notices are retained in all copies and that this
00010 * notice and the following disclaimer are included verbatim in any 
00011 * distributions. No written agreement, license, or royalty fee is required
00012 * for any of the authorized uses.
00013 *
00014 * THIS SOFTWARE IS PROVIDED BY THE CONTRIBUTORS *AS IS* AND ANY EXPRESS OR
00015 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
00016 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 
00017 * IN NO EVENT SHALL THE CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
00018 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
00019 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
00020 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
00021 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
00022 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
00023 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
00024 *
00025 ******************************************************************************
00026 * REVISION HISTORY
00027 *
00028 * 03-01-01 Marc Boucher <marc@mbsi.ca>
00029 *   Ported to lwIP.
00030 * 97-12-01 Guy Lancaster <lancasterg@acm.org>, Global Election Systems Inc.
00031 *   Original.
00032 *****************************************************************************/
00033 
00034 /*
00035  * lcp.c - PPP Link Control Protocol.
00036  *
00037  * Copyright (c) 1989 Carnegie Mellon University.
00038  * All rights reserved.
00039  *
00040  * Redistribution and use in source and binary forms are permitted
00041  * provided that the above copyright notice and this paragraph are
00042  * duplicated in all such forms and that any documentation,
00043  * advertising materials, and other materials related to such
00044  * distribution and use acknowledge that the software was developed
00045  * by Carnegie Mellon University.  The name of the
00046  * University may not be used to endorse or promote products derived
00047  * from this software without specific prior written permission.
00048  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
00049  * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
00050  * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
00051  */
00052  
00053 
00054 #include "lwip/opt.h"
00055 
00056 #if PPP_SUPPORT /* don't build if not configured for use in lwipopts.h */
00057 
00058 #include "ppp.h"
00059 #include "pppdebug.h"
00060 
00061 #include "fsm.h"
00062 #include "chap.h"
00063 #include "magic.h"
00064 #include "auth.h"
00065 #include "lcp.h"
00066 
00067 #include <string.h>
00068 
00069 #if PPPOE_SUPPORT
00070 #include "netif/ppp_oe.h"
00071 #else
00072 #define PPPOE_MAXMTU PPP_MAXMRU
00073 #endif
00074 
00075 #if 0 /* UNUSED */
00076 /*
00077  * LCP-related command-line options.
00078  */
00079 int lcp_echo_interval = 0;  /* Interval between LCP echo-requests */
00080 int lcp_echo_fails = 0;     /* Tolerance to unanswered echo-requests */
00081 bool  lax_recv = 0;         /* accept control chars in asyncmap */
00082 
00083 static int setescape (char **);
00084 
00085 static option_t lcp_option_list[] = {
00086     /* LCP options */
00087     /* list stripped for simplicity */
00088     {NULL}
00089 };
00090 #endif /* UNUSED */
00091 
00092 /* options */
00093 LinkPhase lcp_phase[NUM_PPP];          /* Phase of link session (RFC 1661) */
00094 static u_int lcp_echo_interval      = LCP_ECHOINTERVAL; /* Interval between LCP echo-requests */
00095 static u_int lcp_echo_fails         = LCP_MAXECHOFAILS; /* Tolerance to unanswered echo-requests */
00096 
00097 /* global vars */
00098 static fsm lcp_fsm[NUM_PPP];                            /* LCP fsm structure (global)*/
00099 lcp_options lcp_wantoptions[NUM_PPP];  /* Options that we want to request */
00100 lcp_options lcp_gotoptions[NUM_PPP];   /* Options that peer ack'd */
00101 lcp_options lcp_allowoptions[NUM_PPP]; /* Options we allow peer to request */
00102 lcp_options lcp_hisoptions[NUM_PPP];   /* Options that we ack'd */
00103 ext_accm xmit_accm[NUM_PPP];           /* extended transmit ACCM */
00104 
00105 static u32_t lcp_echos_pending      = 0;                /* Number of outstanding echo msgs */
00106 static u32_t lcp_echo_number        = 0;                /* ID number of next echo frame */
00107 static u32_t lcp_echo_timer_running = 0;                /* TRUE if a timer is running */
00108 
00109 /* @todo: do we really need such a large buffer? The typical 1500 bytes seem too much. */
00110 static u_char nak_buffer[PPP_MRU] MEM_POSITION; /* where we construct a nak packet */ 
00111 
00112 /*
00113  * Callbacks for fsm code.  (CI = Configuration Information)
00114  */
00115 static void lcp_resetci (fsm*);                   /* Reset our CI */
00116 static int  lcp_cilen (fsm*);                     /* Return length of our CI */
00117 static void lcp_addci (fsm*, u_char*, int*);      /* Add our CI to pkt */
00118 static int  lcp_ackci (fsm*, u_char*, int);       /* Peer ack'd our CI */
00119 static int  lcp_nakci (fsm*, u_char*, int);       /* Peer nak'd our CI */
00120 static int  lcp_rejci (fsm*, u_char*, int);       /* Peer rej'd our CI */
00121 static int  lcp_reqci (fsm*, u_char*, int*, int); /* Rcv peer CI */
00122 static void lcp_up (fsm*);                        /* We're UP */
00123 static void lcp_down (fsm*);                      /* We're DOWN */
00124 static void lcp_starting (fsm*);                  /* We need lower layer up */
00125 static void lcp_finished (fsm*);                  /* We need lower layer down */
00126 static int  lcp_extcode (fsm*, int, u_char, u_char*, int);
00127 static void lcp_rprotrej (fsm*, u_char*, int);
00128 
00129 /*
00130  * routines to send LCP echos to peer
00131  */
00132 
00133 static void lcp_echo_lowerup (int);
00134 static void lcp_echo_lowerdown (int);
00135 static void LcpEchoTimeout (void*);
00136 static void lcp_received_echo_reply (fsm*, int, u_char*, int);
00137 static void LcpSendEchoRequest (fsm*);
00138 static void LcpLinkFailure (fsm*);
00139 static void LcpEchoCheck (fsm*);
00140 
00141 static fsm_callbacks lcp_callbacks = { /* LCP callback routines */
00142   lcp_resetci,  /* Reset our Configuration Information */
00143   lcp_cilen,    /* Length of our Configuration Information */
00144   lcp_addci,    /* Add our Configuration Information */
00145   lcp_ackci,    /* ACK our Configuration Information */
00146   lcp_nakci,    /* NAK our Configuration Information */
00147   lcp_rejci,    /* Reject our Configuration Information */
00148   lcp_reqci,    /* Request peer's Configuration Information */
00149   lcp_up,       /* Called when fsm reaches LS_OPENED state */
00150   lcp_down,     /* Called when fsm leaves LS_OPENED state */
00151   lcp_starting, /* Called when we want the lower layer up */
00152   lcp_finished, /* Called when we want the lower layer down */
00153   NULL,         /* Called when Protocol-Reject received */
00154   NULL,         /* Retransmission is necessary */
00155   lcp_extcode,  /* Called to handle LCP-specific codes */
00156   "LCP"         /* String name of protocol */
00157 };
00158 
00159 /*
00160  * Protocol entry points.
00161  * Some of these are called directly.
00162  */
00163 
00164 static void lcp_input (int, u_char *, int);
00165 static void lcp_protrej (int);
00166 
00167 struct protent lcp_protent = {
00168     PPP_LCP,
00169     lcp_init,
00170     lcp_input,
00171     lcp_protrej,
00172     lcp_lowerup,
00173     lcp_lowerdown,
00174     lcp_open,
00175     lcp_close,
00176 #if PPP_ADDITIONAL_CALLBACKS
00177     lcp_printpkt,
00178     NULL,
00179 #endif /* PPP_ADDITIONAL_CALLBACKS */
00180     1,
00181     "LCP",
00182 #if PPP_ADDITIONAL_CALLBACKS
00183     NULL,
00184     NULL,
00185     NULL
00186 #endif /* PPP_ADDITIONAL_CALLBACKS */
00187 };
00188 
00189 int lcp_loopbackfail = DEFLOOPBACKFAIL;
00190 
00191 /*
00192  * Length of each type of configuration option (in octets)
00193  */
00194 #define CILEN_VOID  2
00195 #define CILEN_CHAR  3
00196 #define CILEN_SHORT 4 /* CILEN_VOID + sizeof(short) */
00197 #define CILEN_CHAP  5 /* CILEN_VOID + sizeof(short) + 1 */
00198 #define CILEN_LONG  6 /* CILEN_VOID + sizeof(long) */
00199 #define CILEN_LQR   8 /* CILEN_VOID + sizeof(short) + sizeof(long) */
00200 #define CILEN_CBCP  3
00201 
00202 #define CODENAME(x)  ((x) == CONFACK ? "ACK" : (x) == CONFNAK ? "NAK" : "REJ")
00203 
00204 #if 0 /* UNUSED */
00205 /*
00206  * setescape - add chars to the set we escape on transmission.
00207  */
00208 static int
00209 setescape(argv)
00210     char **argv;
00211 {
00212     int n, ret;
00213     char *p, *endp;
00214 
00215     p = *argv;
00216     ret = 1;
00217     while (*p) {
00218       n = strtol(p, &endp, 16);
00219       if (p == endp) {
00220         option_error("escape parameter contains invalid hex number '%s'", p);
00221         return 0;
00222       }
00223       p = endp;
00224       if (n < 0 || n == 0x5E || n > 0xFF) {
00225         option_error("can't escape character 0x%x", n);
00226         ret = 0;
00227       } else
00228         xmit_accm[0][n >> 5] |= 1 << (n & 0x1F);
00229       while (*p == ',' || *p == ' ')
00230         ++p;
00231     }
00232     return ret;
00233 }
00234 #endif /* UNUSED */
00235 
00236 /*
00237  * lcp_init - Initialize LCP.
00238  */
00239 void
00240 lcp_init(int unit)
00241 {
00242   fsm         *f  = &lcp_fsm[unit];
00243   lcp_options *wo = &lcp_wantoptions[unit];
00244   lcp_options *ao = &lcp_allowoptions[unit];
00245 
00246   f->unit      = unit;
00247   f->protocol  = PPP_LCP;
00248   f->callbacks = &lcp_callbacks;
00249 
00250   fsm_init(f);
00251 
00252   wo->passive           = 0;
00253   wo->silent            = 0;
00254   wo->restart           = 0;               /* Set to 1 in kernels or multi-line implementations */
00255   wo->neg_mru           = 1;
00256   wo->mru               = PPP_DEFMRU;
00257   wo->neg_asyncmap      = 1;
00258   wo->asyncmap          = 0x00000000l;     /* Assume don't need to escape any ctl chars. */
00259   wo->neg_chap          = 0;               /* Set to 1 on server */
00260   wo->neg_upap          = 0;               /* Set to 1 on server */
00261   wo->chap_mdtype       = CHAP_DIGEST_MD5;
00262   wo->neg_magicnumber   = 1;
00263   wo->neg_pcompression  = 1;
00264   wo->neg_accompression = 1;
00265   wo->neg_lqr           = 0;               /* no LQR implementation yet */
00266   wo->neg_cbcp          = 0;
00267 
00268   ao->neg_mru           = 1;
00269   ao->mru               = PPP_MAXMRU;
00270   ao->neg_asyncmap      = 1;
00271   ao->asyncmap          = 0x00000000l;     /* Assume don't need to escape any ctl chars. */
00272   ao->neg_chap          = (CHAP_SUPPORT != 0);
00273   ao->chap_mdtype       = CHAP_DIGEST_MD5;
00274   ao->neg_upap          = (PAP_SUPPORT != 0);
00275   ao->neg_magicnumber   = 1;
00276   ao->neg_pcompression  = 1;
00277   ao->neg_accompression = 1;
00278   ao->neg_lqr           = 0;               /* no LQR implementation yet */
00279   ao->neg_cbcp          = (CBCP_SUPPORT != 0);
00280 
00281   /* 
00282    * Set transmit escape for the flag and escape characters plus anything
00283    * set for the allowable options.
00284    */
00285   memset(xmit_accm[unit], 0, sizeof(xmit_accm[0]));
00286   xmit_accm[unit][15] = 0x60;
00287   xmit_accm[unit][0]  = (u_char)((ao->asyncmap        & 0xFF));
00288   xmit_accm[unit][1]  = (u_char)((ao->asyncmap >> 8)  & 0xFF);
00289   xmit_accm[unit][2]  = (u_char)((ao->asyncmap >> 16) & 0xFF);
00290   xmit_accm[unit][3]  = (u_char)((ao->asyncmap >> 24) & 0xFF);
00291   LCPDEBUG(LOG_INFO, ("lcp_init: xmit_accm=%X %X %X %X\n",
00292         xmit_accm[unit][0],
00293         xmit_accm[unit][1],
00294         xmit_accm[unit][2],
00295         xmit_accm[unit][3]));
00296   
00297   lcp_phase[unit] = PHASE_INITIALIZE;
00298 }
00299 
00300 
00301 /*
00302  * lcp_open - LCP is allowed to come up.
00303  */
00304 void
00305 lcp_open(int unit)
00306 {
00307   fsm         *f  = &lcp_fsm[unit];
00308   lcp_options *wo = &lcp_wantoptions[unit];
00309 
00310   f->flags = 0;
00311   if (wo->passive) {
00312     f->flags |= OPT_PASSIVE;
00313   }
00314   if (wo->silent) {
00315     f->flags |= OPT_SILENT;
00316   }
00317   fsm_open(f);
00318 
00319   lcp_phase[unit] = PHASE_ESTABLISH;
00320 }
00321 
00322 
00323 /*
00324  * lcp_close - Take LCP down.
00325  */
00326 void
00327 lcp_close(int unit, char *reason)
00328 {
00329   fsm *f = &lcp_fsm[unit];
00330 
00331   if (lcp_phase[unit] != PHASE_DEAD) {
00332     lcp_phase[unit] = PHASE_TERMINATE;
00333   }
00334   if (f->state == LS_STOPPED && f->flags & (OPT_PASSIVE|OPT_SILENT)) {
00335     /*
00336      * This action is not strictly according to the FSM in RFC1548,
00337      * but it does mean that the program terminates if you do an
00338      * lcp_close() in passive/silent mode when a connection hasn't
00339      * been established.
00340      */
00341     f->state = LS_CLOSED;
00342     lcp_finished(f);
00343   } else {
00344     fsm_close(f, reason);
00345   }
00346 }
00347 
00348 
00349 /*
00350  * lcp_lowerup - The lower layer is up.
00351  */
00352 void
00353 lcp_lowerup(int unit)
00354 {
00355   lcp_options *wo = &lcp_wantoptions[unit];
00356 
00357   /*
00358    * Don't use A/C or protocol compression on transmission,
00359    * but accept A/C and protocol compressed packets
00360    * if we are going to ask for A/C and protocol compression.
00361    */
00362   ppp_set_xaccm(unit, &xmit_accm[unit]);
00363   ppp_send_config(unit, PPP_MRU, 0xffffffffl, 0, 0);
00364   ppp_recv_config(unit, PPP_MRU, 0x00000000l,
00365   wo->neg_pcompression, wo->neg_accompression);
00366   peer_mru[unit] = PPP_MRU;
00367   lcp_allowoptions[unit].asyncmap = (u_long)xmit_accm[unit][0]
00368                                  | ((u_long)xmit_accm[unit][1] << 8)
00369                                  | ((u_long)xmit_accm[unit][2] << 16)
00370                                  | ((u_long)xmit_accm[unit][3] << 24);
00371   LCPDEBUG(LOG_INFO, ("lcp_lowerup: asyncmap=%X %X %X %X\n",
00372             xmit_accm[unit][3],
00373             xmit_accm[unit][2],
00374             xmit_accm[unit][1],
00375             xmit_accm[unit][0]));
00376 
00377   fsm_lowerup(&lcp_fsm[unit]);
00378 }
00379 
00380 
00381 /*
00382  * lcp_lowerdown - The lower layer is down.
00383  */
00384 void
00385 lcp_lowerdown(int unit)
00386 {
00387   fsm_lowerdown(&lcp_fsm[unit]);
00388 }
00389 
00390 
00391 /*
00392  * lcp_input - Input LCP packet.
00393  */
00394 static void
00395 lcp_input(int unit, u_char *p, int len)
00396 {
00397   fsm *f = &lcp_fsm[unit];
00398 
00399   fsm_input(f, p, len);
00400 }
00401 
00402 
00403 /*
00404  * lcp_extcode - Handle a LCP-specific code.
00405  */
00406 static int
00407 lcp_extcode(fsm *f, int code, u_char id, u_char *inp, int len)
00408 {
00409   u_char *magp;
00410 
00411   switch( code ){
00412     case PROTREJ:
00413       lcp_rprotrej(f, inp, len);
00414       break;
00415   
00416     case ECHOREQ:
00417       if (f->state != LS_OPENED) {
00418         break;
00419       }
00420       LCPDEBUG(LOG_INFO, ("lcp: Echo-Request, Rcvd id %d\n", id));
00421       magp = inp;
00422       PUTLONG(lcp_gotoptions[f->unit].magicnumber, magp);
00423       fsm_sdata(f, ECHOREP, id, inp, len);
00424       break;
00425 
00426     case ECHOREP:
00427       lcp_received_echo_reply(f, id, inp, len);
00428       break;
00429 
00430     case DISCREQ:
00431       break;
00432 
00433     default:
00434       return 0;
00435   }
00436   return 1;
00437 }
00438 
00439 
00440 /*
00441  * lcp_rprotrej - Receive an Protocol-Reject.
00442  *
00443  * Figure out which protocol is rejected and inform it.
00444  */
00445 static void
00446 lcp_rprotrej(fsm *f, u_char *inp, int len)
00447 {
00448   int i;
00449   struct protent *protp;
00450   u_short prot;
00451 
00452   if (len < (int)sizeof (u_short)) {
00453     LCPDEBUG(LOG_INFO, ("lcp_rprotrej: Rcvd short Protocol-Reject packet!\n"));
00454     return;
00455   }
00456 
00457   GETSHORT(prot, inp);
00458 
00459   LCPDEBUG(LOG_INFO, ("lcp_rprotrej: Rcvd Protocol-Reject packet for %x!\n", prot));
00460 
00461   /*
00462    * Protocol-Reject packets received in any state other than the LCP
00463    * LS_OPENED state SHOULD be silently discarded.
00464    */
00465   if( f->state != LS_OPENED ) {
00466     LCPDEBUG(LOG_INFO, ("Protocol-Reject discarded: LCP in state %d\n", f->state));
00467     return;
00468   }
00469 
00470   /*
00471    * Upcall the proper Protocol-Reject routine.
00472    */
00473   for (i = 0; (protp = ppp_protocols[i]) != NULL; ++i) {
00474     if (protp->protocol == prot && protp->enabled_flag) {
00475       (*protp->protrej)(f->unit);
00476       return;
00477     }
00478   }
00479 
00480   LCPDEBUG(LOG_WARNING, ("Protocol-Reject for unsupported protocol 0x%x\n", prot));
00481 }
00482 
00483 
00484 /*
00485  * lcp_protrej - A Protocol-Reject was received.
00486  */
00487 static void
00488 lcp_protrej(int unit)
00489 {
00490   LWIP_UNUSED_ARG(unit);
00491   /*
00492    * Can't reject LCP!
00493    */
00494   LCPDEBUG(LOG_WARNING, ("lcp_protrej: Received Protocol-Reject for LCP!\n"));
00495   fsm_protreject(&lcp_fsm[unit]);
00496 }
00497 
00498 
00499 /*
00500  * lcp_sprotrej - Send a Protocol-Reject for some protocol.
00501  */
00502 void
00503 lcp_sprotrej(int unit, u_char *p, int len)
00504 {
00505   /*
00506    * Send back the protocol and the information field of the
00507    * rejected packet.  We only get here if LCP is in the LS_OPENED state.
00508    */
00509 
00510   fsm_sdata(&lcp_fsm[unit], PROTREJ, ++lcp_fsm[unit].id, p, len);
00511 }
00512 
00513 
00514 /*
00515  * lcp_resetci - Reset our CI.
00516  */
00517 static void
00518 lcp_resetci(fsm *f)
00519 {
00520   lcp_wantoptions[f->unit].magicnumber = magic();
00521   lcp_wantoptions[f->unit].numloops = 0;
00522   lcp_gotoptions[f->unit] = lcp_wantoptions[f->unit];
00523   peer_mru[f->unit] = PPP_MRU;
00524   auth_reset(f->unit);
00525 }
00526 
00527 
00528 /*
00529  * lcp_cilen - Return length of our CI.
00530  */
00531 static int
00532 lcp_cilen(fsm *f)
00533 {
00534   lcp_options *go = &lcp_gotoptions[f->unit];
00535 
00536 #define LENCIVOID(neg)  ((neg) ? CILEN_VOID : 0)
00537 #define LENCICHAP(neg)  ((neg) ? CILEN_CHAP : 0)
00538 #define LENCISHORT(neg) ((neg) ? CILEN_SHORT : 0)
00539 #define LENCILONG(neg)  ((neg) ? CILEN_LONG : 0)
00540 #define LENCILQR(neg)   ((neg) ? CILEN_LQR: 0)
00541 #define LENCICBCP(neg)  ((neg) ? CILEN_CBCP: 0)
00542   /*
00543    * NB: we only ask for one of CHAP and UPAP, even if we will
00544    * accept either.
00545    */
00546   return (LENCISHORT(go->neg_mru && go->mru != PPP_DEFMRU) +
00547           LENCILONG(go->neg_asyncmap && go->asyncmap != 0xFFFFFFFFl) +
00548           LENCICHAP(go->neg_chap) +
00549           LENCISHORT(!go->neg_chap && go->neg_upap) +
00550           LENCILQR(go->neg_lqr) +
00551           LENCICBCP(go->neg_cbcp) +
00552           LENCILONG(go->neg_magicnumber) +
00553           LENCIVOID(go->neg_pcompression) +
00554           LENCIVOID(go->neg_accompression));
00555 }
00556 
00557 
00558 /*
00559  * lcp_addci - Add our desired CIs to a packet.
00560  */
00561 static void
00562 lcp_addci(fsm *f, u_char *ucp, int *lenp)
00563 {
00564   lcp_options *go = &lcp_gotoptions[f->unit];
00565   u_char *start_ucp = ucp;
00566 
00567 #define ADDCIVOID(opt, neg) \
00568   if (neg) { \
00569     LCPDEBUG(LOG_INFO, ("lcp_addci: opt=%d\n", opt)); \
00570     PUTCHAR(opt, ucp); \
00571     PUTCHAR(CILEN_VOID, ucp); \
00572   }
00573 #define ADDCISHORT(opt, neg, val) \
00574   if (neg) { \
00575     LCPDEBUG(LOG_INFO, ("lcp_addci: INT opt=%d %X\n", opt, val)); \
00576     PUTCHAR(opt, ucp); \
00577     PUTCHAR(CILEN_SHORT, ucp); \
00578     PUTSHORT(val, ucp); \
00579   }
00580 #define ADDCICHAP(opt, neg, val, digest) \
00581   if (neg) { \
00582     LCPDEBUG(LOG_INFO, ("lcp_addci: CHAP opt=%d %X\n", opt, val)); \
00583     PUTCHAR(opt, ucp); \
00584     PUTCHAR(CILEN_CHAP, ucp); \
00585     PUTSHORT(val, ucp); \
00586     PUTCHAR(digest, ucp); \
00587   }
00588 #define ADDCILONG(opt, neg, val) \
00589   if (neg) { \
00590     LCPDEBUG(LOG_INFO, ("lcp_addci: L opt=%d %lX\n", opt, val)); \
00591     PUTCHAR(opt, ucp); \
00592     PUTCHAR(CILEN_LONG, ucp); \
00593     PUTLONG(val, ucp); \
00594   }
00595 #define ADDCILQR(opt, neg, val) \
00596   if (neg) { \
00597     LCPDEBUG(LOG_INFO, ("lcp_addci: LQR opt=%d %lX\n", opt, val)); \
00598     PUTCHAR(opt, ucp); \
00599     PUTCHAR(CILEN_LQR, ucp); \
00600     PUTSHORT(PPP_LQR, ucp); \
00601     PUTLONG(val, ucp); \
00602   }
00603 #define ADDCICHAR(opt, neg, val) \
00604   if (neg) { \
00605     LCPDEBUG(LOG_INFO, ("lcp_addci: CHAR opt=%d %X '%z'\n", opt, val, val)); \
00606     PUTCHAR(opt, ucp); \
00607     PUTCHAR(CILEN_CHAR, ucp); \
00608     PUTCHAR(val, ucp); \
00609   }
00610 
00611   ADDCISHORT(CI_MRU, go->neg_mru && go->mru != PPP_DEFMRU, go->mru);
00612   ADDCILONG(CI_ASYNCMAP, go->neg_asyncmap && go->asyncmap != 0xFFFFFFFFl, go->asyncmap);
00613   ADDCICHAP(CI_AUTHTYPE, go->neg_chap, PPP_CHAP, go->chap_mdtype);
00614   ADDCISHORT(CI_AUTHTYPE, !go->neg_chap && go->neg_upap, PPP_PAP);
00615   ADDCILQR(CI_QUALITY, go->neg_lqr, go->lqr_period);
00616   ADDCICHAR(CI_CALLBACK, go->neg_cbcp, CBCP_OPT);
00617   ADDCILONG(CI_MAGICNUMBER, go->neg_magicnumber, go->magicnumber);
00618   ADDCIVOID(CI_PCOMPRESSION, go->neg_pcompression);
00619   ADDCIVOID(CI_ACCOMPRESSION, go->neg_accompression);
00620 
00621   if (ucp - start_ucp != *lenp) {
00622     /* this should never happen, because peer_mtu should be 1500 */
00623     LCPDEBUG(LOG_ERR, ("Bug in lcp_addci: wrong length\n"));
00624   }
00625 }
00626 
00627 
00628 /*
00629  * lcp_ackci - Ack our CIs.
00630  * This should not modify any state if the Ack is bad.
00631  *
00632  * Returns:
00633  *  0 - Ack was bad.
00634  *  1 - Ack was good.
00635  */
00636 static int
00637 lcp_ackci(fsm *f, u_char *p, int len)
00638 {
00639   lcp_options *go = &lcp_gotoptions[f->unit];
00640   u_char cilen, citype, cichar;
00641   u_short cishort;
00642   u32_t cilong;
00643 
00644   /*
00645    * CIs must be in exactly the same order that we sent.
00646    * Check packet length and CI length at each step.
00647    * If we find any deviations, then this packet is bad.
00648    */
00649 #define ACKCIVOID(opt, neg) \
00650   if (neg) { \
00651     if ((len -= CILEN_VOID) < 0) \
00652       goto bad; \
00653     GETCHAR(citype, p); \
00654     GETCHAR(cilen, p); \
00655     if (cilen != CILEN_VOID || citype != opt) \
00656       goto bad; \
00657   }
00658 #define ACKCISHORT(opt, neg, val) \
00659   if (neg) { \
00660     if ((len -= CILEN_SHORT) < 0) \
00661       goto bad; \
00662     GETCHAR(citype, p); \
00663     GETCHAR(cilen, p); \
00664     if (cilen != CILEN_SHORT || citype != opt) \
00665       goto bad; \
00666     GETSHORT(cishort, p); \
00667     if (cishort != val) \
00668       goto bad; \
00669   }
00670 #define ACKCICHAR(opt, neg, val) \
00671   if (neg) { \
00672     if ((len -= CILEN_CHAR) < 0) \
00673       goto bad; \
00674     GETCHAR(citype, p); \
00675     GETCHAR(cilen, p); \
00676     if (cilen != CILEN_CHAR || citype != opt) \
00677       goto bad; \
00678     GETCHAR(cichar, p); \
00679     if (cichar != val) \
00680       goto bad; \
00681   }
00682 #define ACKCICHAP(opt, neg, val, digest) \
00683   if (neg) { \
00684     if ((len -= CILEN_CHAP) < 0) \
00685       goto bad; \
00686     GETCHAR(citype, p); \
00687     GETCHAR(cilen, p); \
00688     if (cilen != CILEN_CHAP || citype != opt) \
00689       goto bad; \
00690     GETSHORT(cishort, p); \
00691     if (cishort != val) \
00692       goto bad; \
00693     GETCHAR(cichar, p); \
00694     if (cichar != digest) \
00695       goto bad; \
00696   }
00697 #define ACKCILONG(opt, neg, val) \
00698   if (neg) { \
00699     if ((len -= CILEN_LONG) < 0) \
00700       goto bad; \
00701     GETCHAR(citype, p); \
00702     GETCHAR(cilen, p); \
00703     if (cilen != CILEN_LONG ||  citype != opt) \
00704       goto bad; \
00705     GETLONG(cilong, p); \
00706     if (cilong != val) \
00707       goto bad; \
00708   }
00709 #define ACKCILQR(opt, neg, val) \
00710   if (neg) { \
00711     if ((len -= CILEN_LQR) < 0) \
00712       goto bad; \
00713     GETCHAR(citype, p); \
00714     GETCHAR(cilen, p); \
00715     if (cilen != CILEN_LQR || citype != opt) \
00716       goto bad; \
00717     GETSHORT(cishort, p); \
00718     if (cishort != PPP_LQR) \
00719       goto bad; \
00720     GETLONG(cilong, p); \
00721     if (cilong != val) \
00722       goto bad; \
00723   }
00724 
00725   ACKCISHORT(CI_MRU, go->neg_mru && go->mru != PPP_DEFMRU, go->mru);
00726   ACKCILONG(CI_ASYNCMAP, go->neg_asyncmap && go->asyncmap != 0xFFFFFFFFl, go->asyncmap);
00727   ACKCICHAP(CI_AUTHTYPE, go->neg_chap, PPP_CHAP, go->chap_mdtype);
00728   ACKCISHORT(CI_AUTHTYPE, !go->neg_chap && go->neg_upap, PPP_PAP);
00729   ACKCILQR(CI_QUALITY, go->neg_lqr, go->lqr_period);
00730   ACKCICHAR(CI_CALLBACK, go->neg_cbcp, CBCP_OPT);
00731   ACKCILONG(CI_MAGICNUMBER, go->neg_magicnumber, go->magicnumber);
00732   ACKCIVOID(CI_PCOMPRESSION, go->neg_pcompression);
00733   ACKCIVOID(CI_ACCOMPRESSION, go->neg_accompression);
00734 
00735   /*
00736    * If there are any remaining CIs, then this packet is bad.
00737    */
00738   if (len != 0) {
00739     goto bad;
00740   }
00741   LCPDEBUG(LOG_INFO, ("lcp_acki: Ack\n"));
00742   return (1);
00743 bad:
00744   LCPDEBUG(LOG_WARNING, ("lcp_acki: received bad Ack!\n"));
00745   return (0);
00746 }
00747 
00748 
00749 /*
00750  * lcp_nakci - Peer has sent a NAK for some of our CIs.
00751  * This should not modify any state if the Nak is bad
00752  * or if LCP is in the LS_OPENED state.
00753  *
00754  * Returns:
00755  *  0 - Nak was bad.
00756  *  1 - Nak was good.
00757  */
00758 static int
00759 lcp_nakci(fsm *f, u_char *p, int len)
00760 {
00761   lcp_options *go = &lcp_gotoptions[f->unit];
00762   lcp_options *wo = &lcp_wantoptions[f->unit];
00763   u_char citype, cichar, *next;
00764   u_short cishort;
00765   u32_t cilong;
00766   lcp_options no;     /* options we've seen Naks for */
00767   lcp_options try;    /* options to request next time */
00768   int looped_back = 0;
00769   int cilen;
00770 
00771   BZERO(&no, sizeof(no));
00772   try = *go;
00773 
00774   /*
00775    * Any Nak'd CIs must be in exactly the same order that we sent.
00776    * Check packet length and CI length at each step.
00777    * If we find any deviations, then this packet is bad.
00778    */
00779 #define NAKCIVOID(opt, neg, code) \
00780   if (go->neg && \
00781       len >= CILEN_VOID && \
00782       p[1] == CILEN_VOID && \
00783       p[0] == opt) { \
00784     len -= CILEN_VOID; \
00785     INCPTR(CILEN_VOID, p); \
00786     no.neg = 1; \
00787     code \
00788   }
00789 #define NAKCICHAP(opt, neg, code) \
00790   if (go->neg && \
00791       len >= CILEN_CHAP && \
00792       p[1] == CILEN_CHAP && \
00793       p[0] == opt) { \
00794     len -= CILEN_CHAP; \
00795     INCPTR(2, p); \
00796     GETSHORT(cishort, p); \
00797     GETCHAR(cichar, p); \
00798     no.neg = 1; \
00799     code \
00800   }
00801 #define NAKCICHAR(opt, neg, code) \
00802   if (go->neg && \
00803       len >= CILEN_CHAR && \
00804       p[1] == CILEN_CHAR && \
00805       p[0] == opt) { \
00806     len -= CILEN_CHAR; \
00807     INCPTR(2, p); \
00808     GETCHAR(cichar, p); \
00809     no.neg = 1; \
00810     code \
00811   }
00812 #define NAKCISHORT(opt, neg, code) \
00813   if (go->neg && \
00814       len >= CILEN_SHORT && \
00815       p[1] == CILEN_SHORT && \
00816       p[0] == opt) { \
00817     len -= CILEN_SHORT; \
00818     INCPTR(2, p); \
00819     GETSHORT(cishort, p); \
00820     no.neg = 1; \
00821     code \
00822   }
00823 #define NAKCILONG(opt, neg, code) \
00824   if (go->neg && \
00825       len >= CILEN_LONG && \
00826       p[1] == CILEN_LONG && \
00827       p[0] == opt) { \
00828     len -= CILEN_LONG; \
00829     INCPTR(2, p); \
00830     GETLONG(cilong, p); \
00831     no.neg = 1; \
00832     code \
00833   }
00834 #define NAKCILQR(opt, neg, code) \
00835   if (go->neg && \
00836       len >= CILEN_LQR && \
00837       p[1] == CILEN_LQR && \
00838       p[0] == opt) { \
00839     len -= CILEN_LQR; \
00840     INCPTR(2, p); \
00841     GETSHORT(cishort, p); \
00842     GETLONG(cilong, p); \
00843     no.neg = 1; \
00844     code \
00845   }
00846 
00847   /*
00848    * We don't care if they want to send us smaller packets than
00849    * we want.  Therefore, accept any MRU less than what we asked for,
00850    * but then ignore the new value when setting the MRU in the kernel.
00851    * If they send us a bigger MRU than what we asked, accept it, up to
00852    * the limit of the default MRU we'd get if we didn't negotiate.
00853    */
00854   if (go->neg_mru && go->mru != PPP_DEFMRU) {
00855     NAKCISHORT(CI_MRU, neg_mru,
00856       if (cishort <= wo->mru || cishort < PPP_DEFMRU) {
00857         try.mru = cishort;
00858       }
00859     );
00860   }
00861 
00862   /*
00863    * Add any characters they want to our (receive-side) asyncmap.
00864    */
00865   if (go->neg_asyncmap && go->asyncmap != 0xFFFFFFFFl) {
00866     NAKCILONG(CI_ASYNCMAP, neg_asyncmap,
00867       try.asyncmap = go->asyncmap | cilong;
00868     );
00869   }
00870 
00871   /*
00872    * If they've nak'd our authentication-protocol, check whether
00873    * they are proposing a different protocol, or a different
00874    * hash algorithm for CHAP.
00875    */
00876   if ((go->neg_chap || go->neg_upap)
00877       && len >= CILEN_SHORT
00878       && p[0] == CI_AUTHTYPE && p[1] >= CILEN_SHORT && p[1] <= len) {
00879     cilen = p[1];
00880     len -= cilen;
00881     no.neg_chap = go->neg_chap;
00882     no.neg_upap = go->neg_upap;
00883     INCPTR(2, p);
00884     GETSHORT(cishort, p);
00885     if (cishort == PPP_PAP && cilen == CILEN_SHORT) {
00886       /*
00887        * If we were asking for CHAP, they obviously don't want to do it.
00888        * If we weren't asking for CHAP, then we were asking for PAP,
00889        * in which case this Nak is bad.
00890        */
00891       if (!go->neg_chap) {
00892         goto bad;
00893       }
00894       try.neg_chap = 0;
00895     
00896     } else if (cishort == PPP_CHAP && cilen == CILEN_CHAP) {
00897       GETCHAR(cichar, p);
00898       if (go->neg_chap) {
00899         /*
00900          * We were asking for CHAP/MD5; they must want a different
00901          * algorithm.  If they can't do MD5, we'll have to stop
00902          * asking for CHAP.
00903          */
00904         if (cichar != go->chap_mdtype) {
00905           try.neg_chap = 0;
00906         }
00907       } else {
00908         /*
00909          * Stop asking for PAP if we were asking for it.
00910          */
00911         try.neg_upap = 0;
00912       }
00913     
00914     } else {
00915       /*
00916        * We don't recognize what they're suggesting.
00917        * Stop asking for what we were asking for.
00918        */
00919       if (go->neg_chap) {
00920         try.neg_chap = 0;
00921       } else {
00922         try.neg_upap = 0;
00923       }
00924       p += cilen - CILEN_SHORT;
00925     }
00926   }
00927 
00928   /*
00929    * If they can't cope with our link quality protocol, we'll have
00930    * to stop asking for LQR.  We haven't got any other protocol.
00931    * If they Nak the reporting period, take their value XXX ?
00932    */
00933   NAKCILQR(CI_QUALITY, neg_lqr,
00934     if (cishort != PPP_LQR) {
00935       try.neg_lqr = 0;
00936     } else {
00937       try.lqr_period = cilong;
00938     }
00939   );
00940 
00941   /*
00942    * Only implementing CBCP...not the rest of the callback options
00943    */
00944   NAKCICHAR(CI_CALLBACK, neg_cbcp,
00945     try.neg_cbcp = 0;
00946   );
00947 
00948   /*
00949    * Check for a looped-back line.
00950    */
00951   NAKCILONG(CI_MAGICNUMBER, neg_magicnumber,
00952     try.magicnumber = magic();
00953     looped_back = 1;
00954   );
00955 
00956   /*
00957    * Peer shouldn't send Nak for protocol compression or
00958    * address/control compression requests; they should send
00959    * a Reject instead.  If they send a Nak, treat it as a Reject.
00960    */
00961   NAKCIVOID(CI_PCOMPRESSION, neg_pcompression,
00962     try.neg_pcompression = 0;
00963   );
00964   NAKCIVOID(CI_ACCOMPRESSION, neg_accompression,
00965     try.neg_accompression = 0;
00966   );
00967 
00968   /*
00969    * There may be remaining CIs, if the peer is requesting negotiation
00970    * on an option that we didn't include in our request packet.
00971    * If we see an option that we requested, or one we've already seen
00972    * in this packet, then this packet is bad.
00973    * If we wanted to respond by starting to negotiate on the requested
00974    * option(s), we could, but we don't, because except for the
00975    * authentication type and quality protocol, if we are not negotiating
00976    * an option, it is because we were told not to.
00977    * For the authentication type, the Nak from the peer means
00978    * `let me authenticate myself with you' which is a bit pointless.
00979    * For the quality protocol, the Nak means `ask me to send you quality
00980    * reports', but if we didn't ask for them, we don't want them.
00981    * An option we don't recognize represents the peer asking to
00982    * negotiate some option we don't support, so ignore it.
00983    */
00984   while (len > CILEN_VOID) {
00985     GETCHAR(citype, p);
00986     GETCHAR(cilen, p);
00987     if (cilen < CILEN_VOID || (len -= cilen) < 0) {
00988       goto bad;
00989     }
00990     next = p + cilen - 2;
00991 
00992     switch (citype) {
00993       case CI_MRU:
00994         if ((go->neg_mru && go->mru != PPP_DEFMRU)
00995             || no.neg_mru || cilen != CILEN_SHORT) {
00996           goto bad;
00997         }
00998         GETSHORT(cishort, p);
00999         if (cishort < PPP_DEFMRU) {
01000           try.mru = cishort;
01001         }
01002         break;
01003       case CI_ASYNCMAP:
01004         if ((go->neg_asyncmap && go->asyncmap != 0xFFFFFFFFl)
01005             || no.neg_asyncmap || cilen != CILEN_LONG) {
01006           goto bad;
01007         }
01008         break;
01009       case CI_AUTHTYPE:
01010         if (go->neg_chap || no.neg_chap || go->neg_upap || no.neg_upap) {
01011           goto bad;
01012         }
01013         break;
01014       case CI_MAGICNUMBER:
01015         if (go->neg_magicnumber || no.neg_magicnumber ||
01016             cilen != CILEN_LONG) {
01017           goto bad;
01018         }
01019         break;
01020       case CI_PCOMPRESSION:
01021         if (go->neg_pcompression || no.neg_pcompression
01022             || cilen != CILEN_VOID) {
01023           goto bad;
01024         }
01025         break;
01026       case CI_ACCOMPRESSION:
01027         if (go->neg_accompression || no.neg_accompression
01028             || cilen != CILEN_VOID) {
01029           goto bad;
01030         }
01031         break;
01032       case CI_QUALITY:
01033         if (go->neg_lqr || no.neg_lqr || cilen != CILEN_LQR) {
01034           goto bad;
01035         }
01036         break;
01037     }
01038     p = next;
01039   }
01040 
01041   /* If there is still anything left, this packet is bad. */
01042   if (len != 0) {
01043     goto bad;
01044   }
01045 
01046   /*
01047   * OK, the Nak is good.  Now we can update state.
01048   */
01049   if (f->state != LS_OPENED) {
01050     if (looped_back) {
01051       if (++try.numloops >= lcp_loopbackfail) {
01052         LCPDEBUG(LOG_NOTICE, ("Serial line is looped back.\n"));
01053         lcp_close(f->unit, "Loopback detected");
01054       }
01055     } else {
01056       try.numloops = 0;
01057     }
01058     *go = try;
01059   }
01060 
01061   return 1;
01062 
01063 bad:
01064   LCPDEBUG(LOG_WARNING, ("lcp_nakci: received bad Nak!\n"));
01065   return 0;
01066 }
01067 
01068 
01069 /*
01070  * lcp_rejci - Peer has Rejected some of our CIs.
01071  * This should not modify any state if the Reject is bad
01072  * or if LCP is in the LS_OPENED state.
01073  *
01074  * Returns:
01075  *  0 - Reject was bad.
01076  *  1 - Reject was good.
01077  */
01078 static int
01079 lcp_rejci(fsm *f, u_char *p, int len)
01080 {
01081   lcp_options *go = &lcp_gotoptions[f->unit];
01082   u_char cichar;
01083   u_short cishort;
01084   u32_t cilong;
01085   lcp_options try; /* options to request next time */
01086 
01087   try = *go;
01088 
01089   /*
01090    * Any Rejected CIs must be in exactly the same order that we sent.
01091    * Check packet length and CI length at each step.
01092    * If we find any deviations, then this packet is bad.
01093    */
01094 #define REJCIVOID(opt, neg) \
01095   if (go->neg && \
01096       len >= CILEN_VOID && \
01097       p[1] == CILEN_VOID && \
01098       p[0] == opt) { \
01099     len -= CILEN_VOID; \
01100     INCPTR(CILEN_VOID, p); \
01101     try.neg = 0; \
01102     LCPDEBUG(LOG_INFO, ("lcp_rejci: void opt %d rejected\n", opt)); \
01103   }
01104 #define REJCISHORT(opt, neg, val) \
01105   if (go->neg && \
01106       len >= CILEN_SHORT && \
01107       p[1] == CILEN_SHORT && \
01108       p[0] == opt) { \
01109     len -= CILEN_SHORT; \
01110     INCPTR(2, p); \
01111     GETSHORT(cishort, p); \
01112     /* Check rejected value. */ \
01113     if (cishort != val) { \
01114       goto bad; \
01115     } \
01116     try.neg = 0; \
01117     LCPDEBUG(LOG_INFO, ("lcp_rejci: short opt %d rejected\n", opt)); \
01118   }
01119 #define REJCICHAP(opt, neg, val, digest) \
01120   if (go->neg && \
01121       len >= CILEN_CHAP && \
01122       p[1] == CILEN_CHAP && \
01123       p[0] == opt) { \
01124     len -= CILEN_CHAP; \
01125     INCPTR(2, p); \
01126     GETSHORT(cishort, p); \
01127     GETCHAR(cichar, p); \
01128     /* Check rejected value. */ \
01129     if (cishort != val || cichar != digest) { \
01130       goto bad; \
01131     } \
01132     try.neg = 0; \
01133     try.neg_upap = 0; \
01134     LCPDEBUG(LOG_INFO, ("lcp_rejci: chap opt %d rejected\n", opt)); \
01135   }
01136 #define REJCILONG(opt, neg, val) \
01137   if (go->neg && \
01138       len >= CILEN_LONG && \
01139       p[1] == CILEN_LONG && \
01140       p[0] == opt) { \
01141     len -= CILEN_LONG; \
01142     INCPTR(2, p); \
01143     GETLONG(cilong, p); \
01144     /* Check rejected value. */ \
01145     if (cilong != val) { \
01146       goto bad; \
01147     } \
01148     try.neg = 0; \
01149     LCPDEBUG(LOG_INFO, ("lcp_rejci: long opt %d rejected\n", opt)); \
01150   }
01151 #define REJCILQR(opt, neg, val) \
01152   if (go->neg && \
01153       len >= CILEN_LQR && \
01154       p[1] == CILEN_LQR && \
01155       p[0] == opt) { \
01156     len -= CILEN_LQR; \
01157     INCPTR(2, p); \
01158     GETSHORT(cishort, p); \
01159     GETLONG(cilong, p); \
01160     /* Check rejected value. */ \
01161     if (cishort != PPP_LQR || cilong != val) { \
01162       goto bad; \
01163     } \
01164     try.neg = 0; \
01165     LCPDEBUG(LOG_INFO, ("lcp_rejci: LQR opt %d rejected\n", opt)); \
01166   }
01167 #define REJCICBCP(opt, neg, val) \
01168   if (go->neg && \
01169       len >= CILEN_CBCP && \
01170       p[1] == CILEN_CBCP && \
01171       p[0] == opt) { \
01172     len -= CILEN_CBCP; \
01173     INCPTR(2, p); \
01174     GETCHAR(cichar, p); \
01175     /* Check rejected value. */ \
01176     if (cichar != val) { \
01177       goto bad; \
01178     } \
01179     try.neg = 0; \
01180     LCPDEBUG(LOG_INFO, ("lcp_rejci: Callback opt %d rejected\n", opt)); \
01181   }
01182   
01183   REJCISHORT(CI_MRU, neg_mru, go->mru);
01184   REJCILONG(CI_ASYNCMAP, neg_asyncmap, go->asyncmap);
01185   REJCICHAP(CI_AUTHTYPE, neg_chap, PPP_CHAP, go->chap_mdtype);
01186   if (!go->neg_chap) {
01187     REJCISHORT(CI_AUTHTYPE, neg_upap, PPP_PAP);
01188   }
01189   REJCILQR(CI_QUALITY, neg_lqr, go->lqr_period);
01190   REJCICBCP(CI_CALLBACK, neg_cbcp, CBCP_OPT);
01191   REJCILONG(CI_MAGICNUMBER, neg_magicnumber, go->magicnumber);
01192   REJCIVOID(CI_PCOMPRESSION, neg_pcompression);
01193   REJCIVOID(CI_ACCOMPRESSION, neg_accompression);
01194   
01195   /*
01196    * If there are any remaining CIs, then this packet is bad.
01197    */
01198   if (len != 0) {
01199     goto bad;
01200   }
01201   /*
01202    * Now we can update state.
01203    */
01204   if (f->state != LS_OPENED) {
01205     *go = try;
01206   }
01207   return 1;
01208   
01209 bad:
01210   LCPDEBUG(LOG_WARNING, ("lcp_rejci: received bad Reject!\n"));
01211   return 0;
01212 }
01213 
01214 
01215 /*
01216  * lcp_reqci - Check the peer's requested CIs and send appropriate response.
01217  *
01218  * Returns: CONFACK, CONFNAK or CONFREJ and input packet modified
01219  * appropriately.  If reject_if_disagree is non-zero, doesn't return
01220  * CONFNAK; returns CONFREJ if it can't return CONFACK.
01221  */
01222 static int
01223 lcp_reqci(fsm *f, 
01224           u_char *inp,    /* Requested CIs */
01225           int *lenp,      /* Length of requested CIs */
01226           int reject_if_disagree)
01227 {
01228   lcp_options *go = &lcp_gotoptions[f->unit];
01229   lcp_options *ho = &lcp_hisoptions[f->unit];
01230   lcp_options *ao = &lcp_allowoptions[f->unit];
01231   u_char *cip, *next;         /* Pointer to current and next CIs */
01232   int cilen, citype;          /* Parsed len, type */
01233   u_char cichar;              /* Parsed char value */
01234   u_short cishort;            /* Parsed short value */
01235   u32_t cilong;               /* Parse long value */
01236   int rc = CONFACK;           /* Final packet return code */
01237   int orc;                    /* Individual option return code */
01238   u_char *p;                  /* Pointer to next char to parse */
01239   u_char *rejp;               /* Pointer to next char in reject frame */
01240   u_char *nakp;               /* Pointer to next char in Nak frame */
01241   int l = *lenp;              /* Length left */
01242 #if TRACELCP > 0
01243   char traceBuf[80];
01244   size_t traceNdx = 0;
01245 #endif
01246 
01247   /*
01248    * Reset all his options.
01249    */
01250   BZERO(ho, sizeof(*ho));
01251 
01252   /*
01253    * Process all his options.
01254    */
01255   next = inp;
01256   nakp = nak_buffer;
01257   rejp = inp;
01258   while (l) {
01259     orc = CONFACK;      /* Assume success */
01260     cip = p = next;     /* Remember begining of CI */
01261     if (l < 2 ||        /* Not enough data for CI header or */
01262         p[1] < 2 ||     /*  CI length too small or */
01263         p[1] > l) {     /*  CI length too big? */
01264       LCPDEBUG(LOG_WARNING, ("lcp_reqci: bad CI length!\n"));
01265       orc = CONFREJ;    /* Reject bad CI */
01266       cilen = l;        /* Reject till end of packet */
01267       l = 0;            /* Don't loop again */
01268       citype = 0;
01269       goto endswitch;
01270     }
01271     GETCHAR(citype, p); /* Parse CI type */
01272     GETCHAR(cilen, p);  /* Parse CI length */
01273     l -= cilen;         /* Adjust remaining length */
01274     next += cilen;      /* Step to next CI */
01275 
01276     switch (citype) {   /* Check CI type */
01277       case CI_MRU:
01278         if (!ao->neg_mru) {    /* Allow option? */
01279           LCPDEBUG(LOG_INFO, ("lcp_reqci: Reject MRU - not allowed\n"));
01280           orc = CONFREJ;    /* Reject CI */
01281           break;
01282         } else if (cilen != CILEN_SHORT) {  /* Check CI length */
01283           LCPDEBUG(LOG_INFO, ("lcp_reqci: Reject MRU - bad length\n"));
01284           orc = CONFREJ;    /* Reject CI */
01285           break;
01286         }
01287         GETSHORT(cishort, p);  /* Parse MRU */
01288 
01289         /*
01290          * He must be able to receive at least our minimum.
01291          * No need to check a maximum.  If he sends a large number,
01292          * we'll just ignore it.
01293          */
01294         if (cishort < PPP_MINMRU) {
01295           LCPDEBUG(LOG_INFO, ("lcp_reqci: Nak - MRU too small\n"));
01296           orc = CONFNAK;    /* Nak CI */
01297           PUTCHAR(CI_MRU, nakp);
01298           PUTCHAR(CILEN_SHORT, nakp);
01299           PUTSHORT(PPP_MINMRU, nakp);  /* Give him a hint */
01300           break;
01301         }
01302         ho->neg_mru = 1;    /* Remember he sent MRU */
01303         ho->mru = cishort;    /* And remember value */
01304 #if TRACELCP > 0
01305         snprintf(&traceBuf[traceNdx], sizeof(traceBuf), " MRU %d", cishort);
01306         traceNdx = strlen(traceBuf);
01307 #endif
01308         break;
01309 
01310       case CI_ASYNCMAP:
01311         if (!ao->neg_asyncmap) {
01312           LCPDEBUG(LOG_INFO, ("lcp_reqci: Reject ASYNCMAP not allowed\n"));
01313           orc = CONFREJ;
01314           break;
01315         } else if (cilen != CILEN_LONG) {
01316           LCPDEBUG(LOG_INFO, ("lcp_reqci: Reject ASYNCMAP bad length\n"));
01317           orc = CONFREJ;
01318           break;
01319         }
01320         GETLONG(cilong, p);
01321         
01322         /*
01323          * Asyncmap must have set at least the bits
01324          * which are set in lcp_allowoptions[unit].asyncmap.
01325          */
01326         if ((ao->asyncmap & ~cilong) != 0) {
01327           LCPDEBUG(LOG_INFO, ("lcp_reqci: Nak ASYNCMAP %lX missing %lX\n", 
01328                     cilong, ao->asyncmap));
01329           orc = CONFNAK;
01330           PUTCHAR(CI_ASYNCMAP, nakp);
01331           PUTCHAR(CILEN_LONG, nakp);
01332           PUTLONG(ao->asyncmap | cilong, nakp);
01333           break;
01334         }
01335         ho->neg_asyncmap = 1;
01336         ho->asyncmap = cilong;
01337 #if TRACELCP > 0
01338         snprintf(&traceBuf[traceNdx], sizeof(traceBuf), " ASYNCMAP=%lX", cilong);
01339         traceNdx = strlen(traceBuf);
01340 #endif
01341         break;
01342 
01343       case CI_AUTHTYPE:
01344         if (cilen < CILEN_SHORT) {
01345           LCPDEBUG(LOG_INFO, ("lcp_reqci: Reject AUTHTYPE missing arg\n"));
01346           orc = CONFREJ;
01347           break;
01348         } else if (!(ao->neg_upap || ao->neg_chap)) {
01349           /*
01350            * Reject the option if we're not willing to authenticate.
01351            */
01352           LCPDEBUG(LOG_INFO, ("lcp_reqci: Reject AUTHTYPE not allowed\n"));
01353           orc = CONFREJ;
01354           break;
01355         }
01356         GETSHORT(cishort, p);
01357         
01358         /*
01359          * Authtype must be UPAP or CHAP.
01360          *
01361          * Note: if both ao->neg_upap and ao->neg_chap are set,
01362          * and the peer sends a Configure-Request with two
01363          * authenticate-protocol requests, one for CHAP and one
01364          * for UPAP, then we will reject the second request.
01365          * Whether we end up doing CHAP or UPAP depends then on
01366          * the ordering of the CIs in the peer's Configure-Request.
01367          */
01368         
01369         if (cishort == PPP_PAP) {
01370           if (ho->neg_chap) {  /* we've already accepted CHAP */
01371             LCPDEBUG(LOG_WARNING, ("lcp_reqci: Reject AUTHTYPE PAP already accepted\n"));
01372             orc = CONFREJ;
01373             break;
01374           } else if (cilen != CILEN_SHORT) {
01375             LCPDEBUG(LOG_WARNING, ("lcp_reqci: Reject AUTHTYPE PAP bad len\n"));
01376             orc = CONFREJ;
01377             break;
01378           }
01379           if (!ao->neg_upap) {  /* we don't want to do PAP */
01380             LCPDEBUG(LOG_WARNING, ("lcp_reqci: Nak AUTHTYPE PAP not allowed\n"));
01381             orc = CONFNAK;  /* NAK it and suggest CHAP */
01382             PUTCHAR(CI_AUTHTYPE, nakp);
01383             PUTCHAR(CILEN_CHAP, nakp);
01384             PUTSHORT(PPP_CHAP, nakp);
01385             PUTCHAR(ao->chap_mdtype, nakp);
01386             break;
01387           }
01388           ho->neg_upap = 1;
01389 #if TRACELCP > 0
01390           snprintf(&traceBuf[traceNdx], sizeof(traceBuf), " PAP (%X)", cishort);
01391           traceNdx = strlen(traceBuf);
01392 #endif
01393           break;
01394         }
01395         if (cishort == PPP_CHAP) {
01396           if (ho->neg_upap) {  /* we've already accepted PAP */
01397             LCPDEBUG(LOG_WARNING, ("lcp_reqci: Reject AUTHTYPE CHAP accepted PAP\n"));
01398             orc = CONFREJ;
01399             break;
01400           } else if (cilen != CILEN_CHAP) {
01401             LCPDEBUG(LOG_WARNING, ("lcp_reqci: Reject AUTHTYPE CHAP bad len\n"));
01402             orc = CONFREJ;
01403             break;
01404           }
01405           if (!ao->neg_chap) {  /* we don't want to do CHAP */
01406             LCPDEBUG(LOG_WARNING, ("lcp_reqci: Nak AUTHTYPE CHAP not allowed\n"));
01407             orc = CONFNAK;  /* NAK it and suggest PAP */
01408             PUTCHAR(CI_AUTHTYPE, nakp);
01409             PUTCHAR(CILEN_SHORT, nakp);
01410             PUTSHORT(PPP_PAP, nakp);
01411             break;
01412           }
01413           GETCHAR(cichar, p);  /* get digest type*/
01414           if (cichar != CHAP_DIGEST_MD5
01415 #if MSCHAP_SUPPORT
01416               && cichar != CHAP_MICROSOFT
01417 #endif
01418           ) {
01419             LCPDEBUG(LOG_WARNING, ("lcp_reqci: Nak AUTHTYPE CHAP digest=%d\n", (int)cichar));
01420             orc = CONFNAK;
01421             PUTCHAR(CI_AUTHTYPE, nakp);
01422             PUTCHAR(CILEN_CHAP, nakp);
01423             PUTSHORT(PPP_CHAP, nakp);
01424             PUTCHAR(ao->chap_mdtype, nakp);
01425             break;
01426           }
01427 #if TRACELCP > 0
01428           snprintf(&traceBuf[traceNdx], sizeof(traceBuf), " CHAP %X,%d", cishort, (int)cichar);
01429           traceNdx = strlen(traceBuf);
01430 #endif
01431           ho->chap_mdtype = cichar; /* save md type */
01432           ho->neg_chap = 1;
01433           break;
01434         }
01435         
01436         /*
01437          * We don't recognize the protocol they're asking for.
01438          * Nak it with something we're willing to do.
01439          * (At this point we know ao->neg_upap || ao->neg_chap.)
01440          */
01441         orc = CONFNAK;
01442         PUTCHAR(CI_AUTHTYPE, nakp);
01443         if (ao->neg_chap) {
01444           LCPDEBUG(LOG_WARNING, ("lcp_reqci: Nak AUTHTYPE %d req CHAP\n", cishort));
01445           PUTCHAR(CILEN_CHAP, nakp);
01446           PUTSHORT(PPP_CHAP, nakp);
01447           PUTCHAR(ao->chap_mdtype, nakp);
01448         } else {
01449           LCPDEBUG(LOG_WARNING, ("lcp_reqci: Nak AUTHTYPE %d req PAP\n", cishort));
01450           PUTCHAR(CILEN_SHORT, nakp);
01451           PUTSHORT(PPP_PAP, nakp);
01452         }
01453         break;
01454       
01455       case CI_QUALITY:
01456         GETSHORT(cishort, p);
01457         GETLONG(cilong, p);
01458 #if TRACELCP > 0
01459         snprintf(&traceBuf[traceNdx], sizeof(traceBuf), " QUALITY (%x %x)", cishort, (unsigned int) cilong);
01460         traceNdx = strlen(traceBuf);
01461 #endif
01462 
01463         if (!ao->neg_lqr ||
01464             cilen != CILEN_LQR) {
01465           orc = CONFREJ;
01466           break;
01467         }
01468         
01469         /*
01470          * Check the protocol and the reporting period.
01471          * XXX When should we Nak this, and what with?
01472          */
01473         if (cishort != PPP_LQR) {
01474           orc = CONFNAK;
01475           PUTCHAR(CI_QUALITY, nakp);
01476           PUTCHAR(CILEN_LQR, nakp);
01477           PUTSHORT(PPP_LQR, nakp);
01478           PUTLONG(ao->lqr_period, nakp);
01479           break;
01480         }
01481         break;
01482       
01483       case CI_MAGICNUMBER:
01484         if (!(ao->neg_magicnumber || go->neg_magicnumber) ||
01485             cilen != CILEN_LONG) {
01486           orc = CONFREJ;
01487           break;
01488         }
01489         GETLONG(cilong, p);
01490 #if TRACELCP > 0
01491         snprintf(&traceBuf[traceNdx], sizeof(traceBuf), " MAGICNUMBER (%lX)", cilong);
01492         traceNdx = strlen(traceBuf);
01493 #endif
01494 
01495         /*
01496          * He must have a different magic number.
01497          */
01498         if (go->neg_magicnumber &&
01499             cilong == go->magicnumber) {
01500           cilong = magic();  /* Don't put magic() inside macro! */
01501           orc = CONFNAK;
01502           PUTCHAR(CI_MAGICNUMBER, nakp);
01503           PUTCHAR(CILEN_LONG, nakp);
01504           PUTLONG(cilong, nakp);
01505           break;
01506         }
01507         ho->neg_magicnumber = 1;
01508         ho->magicnumber = cilong;
01509         break;
01510       
01511       
01512       case CI_PCOMPRESSION:
01513 #if TRACELCP > 0
01514         snprintf(&traceBuf[traceNdx], sizeof(traceBuf), " PCOMPRESSION");
01515         traceNdx = strlen(traceBuf);
01516 #endif
01517         if (!ao->neg_pcompression ||
01518             cilen != CILEN_VOID) {
01519           orc = CONFREJ;
01520           break;
01521         }
01522         ho->neg_pcompression = 1;
01523         break;
01524       
01525       case CI_ACCOMPRESSION:
01526 #if TRACELCP > 0
01527         snprintf(&traceBuf[traceNdx], sizeof(traceBuf), " ACCOMPRESSION");
01528         traceNdx = strlen(traceBuf);
01529 #endif
01530         if (!ao->neg_accompression ||
01531             cilen != CILEN_VOID) {
01532           orc = CONFREJ;
01533           break;
01534         }
01535         ho->neg_accompression = 1;
01536         break;
01537       
01538       case CI_MRRU:
01539 #if TRACELCP > 0
01540         snprintf(&traceBuf[traceNdx], sizeof(traceBuf), " CI_MRRU");
01541         traceNdx = strlen(traceBuf);
01542 #endif
01543         orc = CONFREJ;
01544         break;
01545       
01546       case CI_SSNHF:
01547 #if TRACELCP > 0
01548         snprintf(&traceBuf[traceNdx], sizeof(traceBuf), " CI_SSNHF");
01549         traceNdx = strlen(traceBuf);
01550 #endif
01551         orc = CONFREJ;
01552         break;
01553       
01554       case CI_EPDISC:
01555 #if TRACELCP > 0
01556         snprintf(&traceBuf[traceNdx], sizeof(traceBuf), " CI_EPDISC");
01557         traceNdx = strlen(traceBuf);
01558 #endif
01559         orc = CONFREJ;
01560         break;
01561       
01562       default:
01563 #if TRACELCP
01564         snprintf(&traceBuf[traceNdx], sizeof(traceBuf), " unknown %d", citype);
01565         traceNdx = strlen(traceBuf);
01566 #endif
01567         orc = CONFREJ;
01568         break;
01569     }
01570 
01571   endswitch:
01572 #if TRACELCP
01573     if (traceNdx >= 80 - 32) {
01574       LCPDEBUG(LOG_INFO, ("lcp_reqci: rcvd%s\n", traceBuf));
01575       traceNdx = 0;
01576     }
01577 #endif
01578     if (orc == CONFACK && /* Good CI */
01579         rc != CONFACK) {  /*  but prior CI wasnt? */
01580       continue;           /* Don't send this one */
01581     }
01582 
01583     if (orc == CONFNAK) {     /* Nak this CI? */
01584       if (reject_if_disagree  /* Getting fed up with sending NAKs? */
01585           && citype != CI_MAGICNUMBER) {
01586         orc = CONFREJ;        /* Get tough if so */
01587       } else {
01588         if (rc == CONFREJ) {  /* Rejecting prior CI? */
01589           continue;           /* Don't send this one */
01590         }
01591         rc = CONFNAK;
01592       }
01593     }
01594     if (orc == CONFREJ) {        /* Reject this CI */
01595       rc = CONFREJ;
01596       if (cip != rejp) {         /* Need to move rejected CI? */
01597         BCOPY(cip, rejp, cilen); /* Move it */
01598       }
01599       INCPTR(cilen, rejp);       /* Update output pointer */
01600     }
01601   }
01602 
01603   /*
01604    * If we wanted to send additional NAKs (for unsent CIs), the
01605    * code would go here.  The extra NAKs would go at *nakp.
01606    * At present there are no cases where we want to ask the
01607    * peer to negotiate an option.
01608    */
01609 
01610   switch (rc) {
01611     case CONFACK:
01612       *lenp = (int)(next - inp);
01613       break;
01614     case CONFNAK:
01615       /*
01616        * Copy the Nak'd options from the nak_buffer to the caller's buffer.
01617        */
01618       *lenp = (int)(nakp - nak_buffer);
01619       BCOPY(nak_buffer, inp, *lenp);
01620       break;
01621     case CONFREJ:
01622       *lenp = (int)(rejp - inp);
01623       break;
01624   }
01625 
01626 #if TRACELCP > 0
01627   if (traceNdx > 0) {
01628     LCPDEBUG(LOG_INFO, ("lcp_reqci: %s\n", traceBuf));
01629   }
01630 #endif
01631   LCPDEBUG(LOG_INFO, ("lcp_reqci: returning CONF%s.\n", CODENAME(rc)));
01632   return (rc);      /* Return final code */
01633 }
01634 
01635 
01636 /*
01637  * lcp_up - LCP has come UP.
01638  */
01639 static void
01640 lcp_up(fsm *f)
01641 {
01642   lcp_options *wo = &lcp_wantoptions[f->unit];
01643   lcp_options *ho = &lcp_hisoptions[f->unit];
01644   lcp_options *go = &lcp_gotoptions[f->unit];
01645   lcp_options *ao = &lcp_allowoptions[f->unit];
01646 
01647   if (!go->neg_magicnumber) {
01648     go->magicnumber = 0;
01649   }
01650   if (!ho->neg_magicnumber) {
01651     ho->magicnumber = 0;
01652   }
01653 
01654   /*
01655    * Set our MTU to the smaller of the MTU we wanted and
01656    * the MRU our peer wanted.  If we negotiated an MRU,
01657    * set our MRU to the larger of value we wanted and
01658    * the value we got in the negotiation.
01659    */
01660   ppp_send_config(f->unit, LWIP_MIN(ao->mru, (ho->neg_mru? ho->mru: PPP_MRU)),
01661                  (ho->neg_asyncmap? ho->asyncmap: 0xffffffffl),
01662                   ho->neg_pcompression, ho->neg_accompression);
01663   /*
01664    * If the asyncmap hasn't been negotiated, we really should
01665    * set the receive asyncmap to ffffffff, but we set it to 0
01666    * for backwards contemptibility.
01667    */
01668   ppp_recv_config(f->unit, (go->neg_mru? LWIP_MAX(wo->mru, go->mru): PPP_MRU),
01669                  (go->neg_asyncmap? go->asyncmap: 0x00000000),
01670                   go->neg_pcompression, go->neg_accompression);
01671 
01672   if (ho->neg_mru) {
01673     peer_mru[f->unit] = ho->mru;
01674   }
01675 
01676   lcp_echo_lowerup(f->unit); /* Enable echo messages */
01677 
01678   link_established(f->unit); /* The link is up; authenticate now */
01679 }
01680 
01681 
01682 /*
01683  * lcp_down - LCP has gone DOWN.
01684  *
01685  * Alert other protocols.
01686  */
01687 static void
01688 lcp_down(fsm *f)
01689 {
01690   lcp_options *go = &lcp_gotoptions[f->unit];
01691 
01692   lcp_echo_lowerdown(f->unit);
01693 
01694   link_down(f->unit);
01695 
01696   ppp_send_config(f->unit, PPP_MRU, 0xffffffffl, 0, 0);
01697   ppp_recv_config(f->unit, PPP_MRU,
01698                   (go->neg_asyncmap? go->asyncmap: 0x00000000),
01699                    go->neg_pcompression, go->neg_accompression);
01700   peer_mru[f->unit] = PPP_MRU;
01701 }
01702 
01703 
01704 /*
01705  * lcp_starting - LCP needs the lower layer up.
01706  */
01707 static void
01708 lcp_starting(fsm *f)
01709 {
01710   link_required(f->unit); /* lwip: currently does nothing */
01711 }
01712 
01713 
01714 /*
01715  * lcp_finished - LCP has finished with the lower layer.
01716  */
01717 static void
01718 lcp_finished(fsm *f)
01719 {
01720   link_terminated(f->unit); /* we are finished with the link */
01721 }
01722 
01723 
01724 #if PPP_ADDITIONAL_CALLBACKS
01725 /*
01726  * print_string - print a readable representation of a string using
01727  * printer.
01728  */
01729 static void
01730 print_string( char *p, int len, void (*printer) (void *, char *, ...), void *arg)
01731 {
01732   int c;
01733   
01734   printer(arg, "\"");
01735   for (; len > 0; --len) {
01736     c = *p++;
01737     if (' ' <= c && c <= '~') {
01738         if (c == '\\' || c == '"') {
01739           printer(arg, "\\");
01740         }
01741         printer(arg, "%c", c);
01742     } else {
01743       switch (c) {
01744         case '\n':
01745           printer(arg, "\\n");
01746           break;
01747         case '\r':
01748           printer(arg, "\\r");
01749           break;
01750         case '\t':
01751           printer(arg, "\\t");
01752           break;
01753         default:
01754           printer(arg, "\\%.3o", c);
01755         }
01756     }
01757   }
01758   printer(arg, "\"");
01759 }
01760 
01761 
01762 /*
01763  * lcp_printpkt - print the contents of an LCP packet.
01764  */
01765 static char *lcp_codenames[] = {
01766   "ConfReq", "ConfAck", "ConfNak", "ConfRej",
01767   "TermReq", "TermAck", "CodeRej", "ProtRej",
01768   "EchoReq", "EchoRep", "DiscReq"
01769 };
01770 
01771 static int
01772 lcp_printpkt( u_char *p, int plen, void (*printer) (void *, char *, ...), void *arg)
01773 {
01774   int code, id, len, olen;
01775   u_char *pstart, *optend;
01776   u_short cishort;
01777   u32_t cilong;
01778 
01779   if (plen < HEADERLEN) {
01780     return 0;
01781   }
01782   pstart = p;
01783   GETCHAR(code, p);
01784   GETCHAR(id, p);
01785   GETSHORT(len, p);
01786   if (len < HEADERLEN || len > plen) {
01787     return 0;
01788   }
01789 
01790   if (code >= 1 && code <= sizeof(lcp_codenames) / sizeof(char *)) {
01791     printer(arg, " %s", lcp_codenames[code-1]);
01792   } else {
01793     printer(arg, " code=0x%x", code);
01794   }
01795   printer(arg, " id=0x%x", id);
01796   len -= HEADERLEN;
01797   switch (code) {
01798     case CONFREQ:
01799     case CONFACK:
01800     case CONFNAK:
01801     case CONFREJ:
01802       /* print option list */
01803       while (len >= 2) {
01804         GETCHAR(code, p);
01805         GETCHAR(olen, p);
01806         p -= 2;
01807         if (olen < 2 || olen > len) {
01808           break;
01809         }
01810         printer(arg, " <");
01811         len -= olen;
01812         optend = p + olen;
01813         switch (code) {
01814           case CI_MRU:
01815             if (olen == CILEN_SHORT) {
01816               p += 2;
01817               GETSHORT(cishort, p);
01818               printer(arg, "mru %d", cishort);
01819             }
01820             break;
01821           case CI_ASYNCMAP:
01822             if (olen == CILEN_LONG) {
01823               p += 2;
01824               GETLONG(cilong, p);
01825               printer(arg, "asyncmap 0x%lx", cilong);
01826             }
01827             break;
01828           case CI_AUTHTYPE:
01829             if (olen >= CILEN_SHORT) {
01830               p += 2;
01831               printer(arg, "auth ");
01832               GETSHORT(cishort, p);
01833               switch (cishort) {
01834                 case PPP_PAP:
01835                   printer(arg, "pap");
01836                   break;
01837                 case PPP_CHAP:
01838                   printer(arg, "chap");
01839                   break;
01840                 default:
01841                   printer(arg, "0x%x", cishort);
01842               }
01843             }
01844             break;
01845           case CI_QUALITY:
01846             if (olen >= CILEN_SHORT) {
01847               p += 2;
01848               printer(arg, "quality ");
01849               GETSHORT(cishort, p);
01850               switch (cishort) {
01851                 case PPP_LQR:
01852                   printer(arg, "lqr");
01853                   break;
01854                 default:
01855                   printer(arg, "0x%x", cishort);
01856               }
01857             }
01858             break;
01859           case CI_CALLBACK:
01860             if (olen >= CILEN_CHAR) {
01861               p += 2;
01862               printer(arg, "callback ");
01863               GETSHORT(cishort, p);
01864               switch (cishort) {
01865                 case CBCP_OPT:
01866                   printer(arg, "CBCP");
01867                   break;
01868                 default:
01869                   printer(arg, "0x%x", cishort);
01870               }
01871             }
01872             break;
01873           case CI_MAGICNUMBER:
01874             if (olen == CILEN_LONG) {
01875               p += 2;
01876               GETLONG(cilong, p);
01877               printer(arg, "magic 0x%x", cilong);
01878             }
01879             break;
01880           case CI_PCOMPRESSION:
01881             if (olen == CILEN_VOID) {
01882               p += 2;
01883               printer(arg, "pcomp");
01884             }
01885             break;
01886           case CI_ACCOMPRESSION:
01887             if (olen == CILEN_VOID) {
01888               p += 2;
01889               printer(arg, "accomp");
01890             }
01891             break;
01892         }
01893         while (p < optend) {
01894           GETCHAR(code, p);
01895           printer(arg, " %.2x", code);
01896         }
01897         printer(arg, ">");
01898       }
01899       break;
01900     
01901     case TERMACK:
01902     case TERMREQ:
01903       if (len > 0 && *p >= ' ' && *p < 0x7f) {
01904         printer(arg, " ");
01905         print_string((char*)p, len, printer, arg);
01906         p += len;
01907         len = 0;
01908       }
01909       break;
01910     
01911     case ECHOREQ:
01912     case ECHOREP:
01913     case DISCREQ:
01914       if (len >= 4) {
01915         GETLONG(cilong, p);
01916         printer(arg, " magic=0x%x", cilong);
01917         p += 4;
01918         len -= 4;
01919       }
01920       break;
01921   }
01922 
01923   /* print the rest of the bytes in the packet */
01924   for (; len > 0; --len) {
01925     GETCHAR(code, p);
01926     printer(arg, " %.2x", code);
01927   }
01928 
01929   return (int)(p - pstart);
01930 }
01931 #endif /* PPP_ADDITIONAL_CALLBACKS */
01932 
01933 /*
01934  * Time to shut down the link because there is nothing out there.
01935  */
01936 static void
01937 LcpLinkFailure (fsm *f)
01938 {
01939   if (f->state == LS_OPENED) {
01940     LCPDEBUG(LOG_INFO, ("No response to %d echo-requests\n", lcp_echos_pending));
01941     LCPDEBUG(LOG_NOTICE, ("Serial link appears to be disconnected.\n"));
01942     lcp_close(f->unit, "Peer not responding");
01943   }
01944 }
01945 
01946 /*
01947  * Timer expired for the LCP echo requests from this process.
01948  */
01949 static void
01950 LcpEchoCheck (fsm *f)
01951 {
01952   LcpSendEchoRequest (f);
01953 
01954   /*
01955    * Start the timer for the next interval.
01956    */
01957   LWIP_ASSERT("lcp_echo_timer_running == 0", lcp_echo_timer_running == 0);
01958 
01959   TIMEOUT (LcpEchoTimeout, f, lcp_echo_interval);
01960   lcp_echo_timer_running = 1;
01961 }
01962 
01963 /*
01964  * LcpEchoTimeout - Timer expired on the LCP echo
01965  */
01966 static void
01967 LcpEchoTimeout (void *arg)
01968 {
01969   if (lcp_echo_timer_running != 0) {
01970     lcp_echo_timer_running = 0;
01971     LcpEchoCheck ((fsm *) arg);
01972   }
01973 }
01974 
01975 /*
01976  * LcpEchoReply - LCP has received a reply to the echo
01977  */
01978 static void
01979 lcp_received_echo_reply (fsm *f, int id, u_char *inp, int len)
01980 {
01981   u32_t magic;
01982 
01983   LWIP_UNUSED_ARG(id);
01984 
01985   /* Check the magic number - don't count replies from ourselves. */
01986   if (len < 4) {
01987     LCPDEBUG(LOG_WARNING, ("lcp: received short Echo-Reply, length %d\n", len));
01988     return;
01989   }
01990   GETLONG(magic, inp);
01991   if (lcp_gotoptions[f->unit].neg_magicnumber && magic == lcp_gotoptions[f->unit].magicnumber) {
01992     LCPDEBUG(LOG_WARNING, ("appear to have received our own echo-reply!\n"));
01993     return;
01994   }
01995 
01996   /* Reset the number of outstanding echo frames */
01997   lcp_echos_pending = 0;
01998 }
01999 
02000 /*
02001  * LcpSendEchoRequest - Send an echo request frame to the peer
02002  */
02003 static void
02004 LcpSendEchoRequest (fsm *f)
02005 {
02006   u32_t lcp_magic;
02007   u_char pkt[4], *pktp;
02008 
02009   /*
02010    * Detect the failure of the peer at this point.
02011    */
02012   if (lcp_echo_fails != 0) {
02013     if (lcp_echos_pending++ >= lcp_echo_fails) {
02014       LcpLinkFailure(f);
02015       lcp_echos_pending = 0;
02016     }
02017   }
02018 
02019   /*
02020    * Make and send the echo request frame.
02021    */
02022   if (f->state == LS_OPENED) {
02023     lcp_magic = lcp_gotoptions[f->unit].magicnumber;
02024     pktp = pkt;
02025     PUTLONG(lcp_magic, pktp);
02026     fsm_sdata(f, ECHOREQ, (u_char)(lcp_echo_number++ & 0xFF), pkt, (int)(pktp - pkt));
02027   }
02028 }
02029 
02030 /*
02031  * lcp_echo_lowerup - Start the timer for the LCP frame
02032  */
02033 
02034 static void
02035 lcp_echo_lowerup (int unit)
02036 {
02037   fsm *f = &lcp_fsm[unit];
02038 
02039   /* Clear the parameters for generating echo frames */
02040   lcp_echos_pending      = 0;
02041   lcp_echo_number        = 0;
02042   lcp_echo_timer_running = 0;
02043 
02044   /* If a timeout interval is specified then start the timer */
02045   if (lcp_echo_interval != 0) {
02046     LcpEchoCheck (f);
02047   }
02048 }
02049 
02050 /*
02051  * lcp_echo_lowerdown - Stop the timer for the LCP frame
02052  */
02053 
02054 static void
02055 lcp_echo_lowerdown (int unit)
02056 {
02057   fsm *f = &lcp_fsm[unit];
02058 
02059   if (lcp_echo_timer_running != 0) {
02060     UNTIMEOUT (LcpEchoTimeout, f);
02061     lcp_echo_timer_running = 0;
02062   }
02063 }
02064 
02065 #endif /* PPP_SUPPORT */