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824 lines
20 KiB
C
824 lines
20 KiB
C
/*
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* chap.c - Crytographic Handshake Authentication Protocol.
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*
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* Copyright (c) 1991 Gregory M. Christy.
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms are permitted
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* provided that the above copyright notice and this paragraph are
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* duplicated in all such forms and that any documentation,
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* advertising materials, and other materials related to such
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* distribution and use acknowledge that the software was developed
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* by Gregory M. Christy. The name of the author may not be used to
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* endorse or promote products derived from this software without
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* specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
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* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
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* WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
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*/
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#ifndef lint
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static char rcsid[] = "$Id: chap.c,v 1.2 1994/09/25 02:31:54 wollman Exp $";
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#endif
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/*
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* TODO:
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*/
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#include <stdio.h>
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#include <sys/types.h>
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#include <sys/time.h>
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#include <syslog.h>
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#include "ppp.h"
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#include "pppd.h"
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#include "chap.h"
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#include "md5.h"
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chap_state chap[NPPP]; /* CHAP state; one for each unit */
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static void ChapChallengeTimeout __ARGS((caddr_t));
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static void ChapResponseTimeout __ARGS((caddr_t));
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static void ChapReceiveChallenge __ARGS((chap_state *, u_char *, int, int));
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static void ChapReceiveResponse __ARGS((chap_state *, u_char *, int, int));
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static void ChapReceiveSuccess __ARGS((chap_state *, u_char *, int, int));
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static void ChapReceiveFailure __ARGS((chap_state *, u_char *, int, int));
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static void ChapSendStatus __ARGS((chap_state *, int));
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static void ChapSendChallenge __ARGS((chap_state *));
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static void ChapSendResponse __ARGS((chap_state *));
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static void ChapGenChallenge __ARGS((chap_state *));
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extern double drand48 __ARGS((void));
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extern void srand48 __ARGS((long));
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/*
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* ChapInit - Initialize a CHAP unit.
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*/
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void
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ChapInit(unit)
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int unit;
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{
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chap_state *cstate = &chap[unit];
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BZERO(cstate, sizeof(*cstate));
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cstate->unit = unit;
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cstate->clientstate = CHAPCS_INITIAL;
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cstate->serverstate = CHAPSS_INITIAL;
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cstate->timeouttime = CHAP_DEFTIMEOUT;
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cstate->max_transmits = CHAP_DEFTRANSMITS;
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srand48((long) time(NULL)); /* joggle random number generator */
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}
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/*
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* ChapAuthWithPeer - Authenticate us with our peer (start client).
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*
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*/
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void
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ChapAuthWithPeer(unit, our_name, digest)
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int unit;
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char *our_name;
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int digest;
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{
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chap_state *cstate = &chap[unit];
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cstate->resp_name = our_name;
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cstate->resp_type = digest;
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if (cstate->clientstate == CHAPCS_INITIAL ||
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cstate->clientstate == CHAPCS_PENDING) {
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/* lower layer isn't up - wait until later */
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cstate->clientstate = CHAPCS_PENDING;
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return;
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}
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/*
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* We get here as a result of LCP coming up.
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* So even if CHAP was open before, we will
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* have to re-authenticate ourselves.
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*/
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cstate->clientstate = CHAPCS_LISTEN;
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}
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/*
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* ChapAuthPeer - Authenticate our peer (start server).
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*/
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void
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ChapAuthPeer(unit, our_name, digest)
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int unit;
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char *our_name;
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int digest;
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{
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chap_state *cstate = &chap[unit];
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cstate->chal_name = our_name;
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cstate->chal_type = digest;
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if (cstate->serverstate == CHAPSS_INITIAL ||
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cstate->serverstate == CHAPSS_PENDING) {
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/* lower layer isn't up - wait until later */
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cstate->serverstate = CHAPSS_PENDING;
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return;
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}
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ChapGenChallenge(cstate);
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ChapSendChallenge(cstate); /* crank it up dude! */
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cstate->serverstate = CHAPSS_INITIAL_CHAL;
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}
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/*
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* ChapChallengeTimeout - Timeout expired on sending challenge.
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*/
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static void
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ChapChallengeTimeout(arg)
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caddr_t arg;
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{
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chap_state *cstate = (chap_state *) arg;
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/* if we aren't sending challenges, don't worry. then again we */
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/* probably shouldn't be here either */
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if (cstate->serverstate != CHAPSS_INITIAL_CHAL &&
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cstate->serverstate != CHAPSS_RECHALLENGE)
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return;
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if (cstate->chal_transmits >= cstate->max_transmits) {
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/* give up on peer */
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syslog(LOG_ERR, "Peer failed to respond to CHAP challenge");
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cstate->serverstate = CHAPSS_BADAUTH;
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auth_peer_fail(cstate->unit, CHAP);
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return;
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}
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ChapSendChallenge(cstate); /* Re-send challenge */
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}
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/*
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* ChapResponseTimeout - Timeout expired on sending response.
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*/
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static void
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ChapResponseTimeout(arg)
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caddr_t arg;
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{
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chap_state *cstate = (chap_state *) arg;
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/* if we aren't sending a response, don't worry. */
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if (cstate->clientstate != CHAPCS_RESPONSE)
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return;
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ChapSendResponse(cstate); /* re-send response */
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}
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/*
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* ChapRechallenge - Time to challenge the peer again.
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*/
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static void
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ChapRechallenge(arg)
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caddr_t arg;
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{
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chap_state *cstate = (chap_state *) arg;
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/* if we aren't sending a response, don't worry. */
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if (cstate->serverstate != CHAPSS_OPEN)
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return;
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ChapGenChallenge(cstate);
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ChapSendChallenge(cstate);
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cstate->serverstate = CHAPSS_RECHALLENGE;
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if (cstate->chal_interval != 0)
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TIMEOUT(ChapRechallenge, (caddr_t) cstate, cstate->chal_interval);
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}
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/*
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* ChapLowerUp - The lower layer is up.
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*
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* Start up if we have pending requests.
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*/
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void
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ChapLowerUp(unit)
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int unit;
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{
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chap_state *cstate = &chap[unit];
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if (cstate->clientstate == CHAPCS_INITIAL)
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cstate->clientstate = CHAPCS_CLOSED;
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else if (cstate->clientstate == CHAPCS_PENDING)
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cstate->clientstate = CHAPCS_LISTEN;
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if (cstate->serverstate == CHAPSS_INITIAL)
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cstate->serverstate = CHAPSS_CLOSED;
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else if (cstate->serverstate == CHAPSS_PENDING) {
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ChapGenChallenge(cstate);
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ChapSendChallenge(cstate);
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cstate->serverstate = CHAPSS_INITIAL_CHAL;
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}
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}
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/*
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* ChapLowerDown - The lower layer is down.
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*
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* Cancel all timeouts.
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*/
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void
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ChapLowerDown(unit)
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int unit;
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{
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chap_state *cstate = &chap[unit];
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/* Timeout(s) pending? Cancel if so. */
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if (cstate->serverstate == CHAPSS_INITIAL_CHAL ||
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cstate->serverstate == CHAPSS_RECHALLENGE)
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UNTIMEOUT(ChapChallengeTimeout, (caddr_t) cstate);
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else if (cstate->serverstate == CHAPSS_OPEN
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&& cstate->chal_interval != 0)
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UNTIMEOUT(ChapRechallenge, (caddr_t) cstate);
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if (cstate->clientstate == CHAPCS_RESPONSE)
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UNTIMEOUT(ChapResponseTimeout, (caddr_t) cstate);
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cstate->clientstate = CHAPCS_INITIAL;
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cstate->serverstate = CHAPSS_INITIAL;
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}
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/*
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* ChapProtocolReject - Peer doesn't grok CHAP.
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*/
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void
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ChapProtocolReject(unit)
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int unit;
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{
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chap_state *cstate = &chap[unit];
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if (cstate->serverstate != CHAPSS_INITIAL &&
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cstate->serverstate != CHAPSS_CLOSED)
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auth_peer_fail(unit, CHAP);
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if (cstate->clientstate != CHAPCS_INITIAL &&
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cstate->clientstate != CHAPCS_CLOSED)
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auth_withpeer_fail(unit, CHAP);
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ChapLowerDown(unit); /* shutdown chap */
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}
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/*
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* ChapInput - Input CHAP packet.
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*/
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void
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ChapInput(unit, inpacket, packet_len)
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int unit;
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u_char *inpacket;
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int packet_len;
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{
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chap_state *cstate = &chap[unit];
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u_char *inp;
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u_char code, id;
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int len;
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/*
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* Parse header (code, id and length).
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* If packet too short, drop it.
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*/
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inp = inpacket;
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if (packet_len < CHAP_HEADERLEN) {
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CHAPDEBUG((LOG_INFO, "ChapInput: rcvd short header."));
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return;
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}
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GETCHAR(code, inp);
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GETCHAR(id, inp);
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GETSHORT(len, inp);
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if (len < CHAP_HEADERLEN) {
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CHAPDEBUG((LOG_INFO, "ChapInput: rcvd illegal length."));
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return;
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}
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if (len > packet_len) {
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CHAPDEBUG((LOG_INFO, "ChapInput: rcvd short packet."));
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return;
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}
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len -= CHAP_HEADERLEN;
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/*
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* Action depends on code (as in fact it usually does :-).
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*/
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switch (code) {
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case CHAP_CHALLENGE:
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ChapReceiveChallenge(cstate, inp, id, len);
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break;
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case CHAP_RESPONSE:
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ChapReceiveResponse(cstate, inp, id, len);
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break;
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case CHAP_FAILURE:
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ChapReceiveFailure(cstate, inp, id, len);
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break;
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case CHAP_SUCCESS:
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ChapReceiveSuccess(cstate, inp, id, len);
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break;
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default: /* Need code reject? */
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syslog(LOG_WARNING, "Unknown CHAP code (%d) received.", code);
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break;
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}
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}
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/*
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* ChapReceiveChallenge - Receive Challenge and send Response.
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*/
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static void
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ChapReceiveChallenge(cstate, inp, id, len)
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chap_state *cstate;
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u_char *inp;
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int id;
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int len;
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{
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int rchallenge_len;
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u_char *rchallenge;
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int secret_len;
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char secret[MAXSECRETLEN];
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char rhostname[256];
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MD5_CTX mdContext;
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CHAPDEBUG((LOG_INFO, "ChapReceiveChallenge: Rcvd id %d.", id));
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if (cstate->clientstate == CHAPCS_CLOSED ||
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cstate->clientstate == CHAPCS_PENDING) {
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CHAPDEBUG((LOG_INFO, "ChapReceiveChallenge: in state %d",
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cstate->clientstate));
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return;
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}
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if (len < 2) {
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CHAPDEBUG((LOG_INFO, "ChapReceiveChallenge: rcvd short packet."));
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return;
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}
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GETCHAR(rchallenge_len, inp);
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len -= sizeof (u_char) + rchallenge_len; /* now name field length */
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if (len < 0) {
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CHAPDEBUG((LOG_INFO, "ChapReceiveChallenge: rcvd short packet."));
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return;
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}
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rchallenge = inp;
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INCPTR(rchallenge_len, inp);
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if (len >= sizeof(rhostname))
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len = sizeof(rhostname) - 1;
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BCOPY(inp, rhostname, len);
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rhostname[len] = '\000';
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CHAPDEBUG((LOG_INFO, "ChapReceiveChallenge: received name field: %s",
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rhostname));
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/* get secret for authenticating ourselves with the specified host */
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if (!get_secret(cstate->unit, cstate->resp_name, rhostname,
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secret, &secret_len, 0)) {
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secret_len = 0; /* assume null secret if can't find one */
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syslog(LOG_WARNING, "No CHAP secret found for authenticating us to %s",
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rhostname);
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}
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/* cancel response send timeout if necessary */
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if (cstate->clientstate == CHAPCS_RESPONSE)
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UNTIMEOUT(ChapResponseTimeout, (caddr_t) cstate);
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cstate->resp_id = id;
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cstate->resp_transmits = 0;
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/* generate MD based on negotiated type */
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switch (cstate->resp_type) {
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case CHAP_DIGEST_MD5: /* only MD5 is defined for now */
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MD5Init(&mdContext);
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MD5Update(&mdContext, &cstate->resp_id, 1);
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MD5Update(&mdContext, secret, secret_len);
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MD5Update(&mdContext, rchallenge, rchallenge_len);
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MD5Final(&mdContext);
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BCOPY(mdContext.digest, cstate->response, MD5_SIGNATURE_SIZE);
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cstate->resp_length = MD5_SIGNATURE_SIZE;
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break;
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default:
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CHAPDEBUG((LOG_INFO, "unknown digest type %d", cstate->resp_type));
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return;
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}
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ChapSendResponse(cstate);
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}
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/*
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* ChapReceiveResponse - Receive and process response.
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*/
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static void
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ChapReceiveResponse(cstate, inp, id, len)
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chap_state *cstate;
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u_char *inp;
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int id;
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int len;
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{
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u_char *remmd, remmd_len;
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int secret_len, old_state;
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int code;
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char rhostname[256];
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u_char buf[256];
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MD5_CTX mdContext;
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u_char msg[256];
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char secret[MAXSECRETLEN];
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CHAPDEBUG((LOG_INFO, "ChapReceiveResponse: Rcvd id %d.", id));
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if (cstate->serverstate == CHAPSS_CLOSED ||
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cstate->serverstate == CHAPSS_PENDING) {
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CHAPDEBUG((LOG_INFO, "ChapReceiveResponse: in state %d",
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cstate->serverstate));
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return;
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}
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if (id != cstate->chal_id)
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return; /* doesn't match ID of last challenge */
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/*
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* If we have received a duplicate or bogus Response,
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* we have to send the same answer (Success/Failure)
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* as we did for the first Response we saw.
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*/
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if (cstate->serverstate == CHAPSS_OPEN) {
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ChapSendStatus(cstate, CHAP_SUCCESS);
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return;
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}
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if (cstate->serverstate == CHAPSS_BADAUTH) {
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ChapSendStatus(cstate, CHAP_FAILURE);
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return;
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}
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if (len < 2) {
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CHAPDEBUG((LOG_INFO, "ChapReceiveResponse: rcvd short packet."));
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return;
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}
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GETCHAR(remmd_len, inp); /* get length of MD */
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remmd = inp; /* get pointer to MD */
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INCPTR(remmd_len, inp);
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len -= sizeof (u_char) + remmd_len;
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if (len < 0) {
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CHAPDEBUG((LOG_INFO, "ChapReceiveResponse: rcvd short packet."));
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return;
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}
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UNTIMEOUT(ChapChallengeTimeout, (caddr_t) cstate);
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if (len >= sizeof(rhostname))
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len = sizeof(rhostname) - 1;
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BCOPY(inp, rhostname, len);
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rhostname[len] = '\000';
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CHAPDEBUG((LOG_INFO, "ChapReceiveResponse: received name field: %s",
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rhostname));
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/*
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* Get secret for authenticating them with us,
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* do the hash ourselves, and compare the result.
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*/
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code = CHAP_FAILURE;
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if (!get_secret(cstate->unit, rhostname, cstate->chal_name,
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secret, &secret_len, 1)) {
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syslog(LOG_WARNING, "No CHAP secret found for authenticating %s",
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rhostname);
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} else {
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/* generate MD based on negotiated type */
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switch (cstate->chal_type) {
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case CHAP_DIGEST_MD5: /* only MD5 is defined for now */
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if (remmd_len != MD5_SIGNATURE_SIZE)
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break; /* it's not even the right length */
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MD5Init(&mdContext);
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MD5Update(&mdContext, &cstate->chal_id, 1);
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MD5Update(&mdContext, secret, secret_len);
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MD5Update(&mdContext, cstate->challenge, cstate->chal_len);
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MD5Final(&mdContext);
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/* compare local and remote MDs and send the appropriate status */
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if (bcmp (mdContext.digest, remmd, MD5_SIGNATURE_SIZE) == 0)
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code = CHAP_SUCCESS; /* they are the same! */
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break;
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default:
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CHAPDEBUG((LOG_INFO, "unknown digest type %d", cstate->chal_type));
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}
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}
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ChapSendStatus(cstate, code);
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if (code == CHAP_SUCCESS) {
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old_state = cstate->serverstate;
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cstate->serverstate = CHAPSS_OPEN;
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if (old_state == CHAPSS_INITIAL_CHAL) {
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auth_peer_success(cstate->unit, CHAP);
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}
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if (cstate->chal_interval != 0)
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TIMEOUT(ChapRechallenge, (caddr_t) cstate, cstate->chal_interval);
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} else {
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syslog(LOG_ERR, "CHAP peer authentication failed");
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cstate->serverstate = CHAPSS_BADAUTH;
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auth_peer_fail(cstate->unit, CHAP);
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}
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}
|
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|
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/*
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* ChapReceiveSuccess - Receive Success
|
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*/
|
|
static void
|
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ChapReceiveSuccess(cstate, inp, id, len)
|
|
chap_state *cstate;
|
|
u_char *inp;
|
|
u_char id;
|
|
int len;
|
|
{
|
|
|
|
CHAPDEBUG((LOG_INFO, "ChapReceiveSuccess: Rcvd id %d.", id));
|
|
|
|
if (cstate->clientstate == CHAPCS_OPEN)
|
|
/* presumably an answer to a duplicate response */
|
|
return;
|
|
|
|
if (cstate->clientstate != CHAPCS_RESPONSE) {
|
|
/* don't know what this is */
|
|
CHAPDEBUG((LOG_INFO, "ChapReceiveSuccess: in state %d\n",
|
|
cstate->clientstate));
|
|
return;
|
|
}
|
|
|
|
UNTIMEOUT(ChapResponseTimeout, (caddr_t) cstate);
|
|
|
|
/*
|
|
* Print message.
|
|
*/
|
|
if (len > 0)
|
|
PRINTMSG(inp, len);
|
|
|
|
cstate->clientstate = CHAPCS_OPEN;
|
|
|
|
auth_withpeer_success(cstate->unit, CHAP);
|
|
}
|
|
|
|
|
|
/*
|
|
* ChapReceiveFailure - Receive failure.
|
|
*/
|
|
static void
|
|
ChapReceiveFailure(cstate, inp, id, len)
|
|
chap_state *cstate;
|
|
u_char *inp;
|
|
u_char id;
|
|
int len;
|
|
{
|
|
u_char msglen;
|
|
u_char *msg;
|
|
|
|
CHAPDEBUG((LOG_INFO, "ChapReceiveFailure: Rcvd id %d.", id));
|
|
|
|
if (cstate->clientstate != CHAPCS_RESPONSE) {
|
|
/* don't know what this is */
|
|
CHAPDEBUG((LOG_INFO, "ChapReceiveFailure: in state %d\n",
|
|
cstate->clientstate));
|
|
return;
|
|
}
|
|
|
|
UNTIMEOUT(ChapResponseTimeout, (caddr_t) cstate);
|
|
|
|
/*
|
|
* Print message.
|
|
*/
|
|
if (len > 0)
|
|
PRINTMSG(inp, len);
|
|
|
|
syslog(LOG_ERR, "CHAP authentication failed");
|
|
auth_withpeer_fail(cstate->unit, CHAP);
|
|
}
|
|
|
|
|
|
/*
|
|
* ChapSendChallenge - Send an Authenticate challenge.
|
|
*/
|
|
static void
|
|
ChapSendChallenge(cstate)
|
|
chap_state *cstate;
|
|
{
|
|
u_char *outp;
|
|
int chal_len, name_len;
|
|
int outlen;
|
|
|
|
chal_len = cstate->chal_len;
|
|
name_len = strlen(cstate->chal_name);
|
|
outlen = CHAP_HEADERLEN + sizeof (u_char) + chal_len + name_len;
|
|
outp = outpacket_buf;
|
|
|
|
MAKEHEADER(outp, CHAP); /* paste in a CHAP header */
|
|
|
|
PUTCHAR(CHAP_CHALLENGE, outp);
|
|
PUTCHAR(cstate->chal_id, outp);
|
|
PUTSHORT(outlen, outp);
|
|
|
|
PUTCHAR(chal_len, outp); /* put length of challenge */
|
|
BCOPY(cstate->challenge, outp, chal_len);
|
|
INCPTR(chal_len, outp);
|
|
|
|
BCOPY(cstate->chal_name, outp, name_len); /* append hostname */
|
|
|
|
output(cstate->unit, outpacket_buf, outlen + DLLHEADERLEN);
|
|
|
|
CHAPDEBUG((LOG_INFO, "ChapSendChallenge: Sent id %d.", cstate->chal_id));
|
|
|
|
TIMEOUT(ChapChallengeTimeout, (caddr_t) cstate, cstate->timeouttime);
|
|
++cstate->chal_transmits;
|
|
}
|
|
|
|
|
|
/*
|
|
* ChapSendStatus - Send a status response (ack or nak).
|
|
*/
|
|
static void
|
|
ChapSendStatus(cstate, code)
|
|
chap_state *cstate;
|
|
int code;
|
|
{
|
|
u_char *outp;
|
|
int outlen, msglen;
|
|
char msg[256];
|
|
|
|
if (code == CHAP_SUCCESS)
|
|
sprintf(msg, "Welcome to %s.", hostname);
|
|
else
|
|
sprintf(msg, "I don't like you. Go 'way.");
|
|
msglen = strlen(msg);
|
|
|
|
outlen = CHAP_HEADERLEN + msglen;
|
|
outp = outpacket_buf;
|
|
|
|
MAKEHEADER(outp, CHAP); /* paste in a header */
|
|
|
|
PUTCHAR(code, outp);
|
|
PUTCHAR(cstate->chal_id, outp);
|
|
PUTSHORT(outlen, outp);
|
|
BCOPY(msg, outp, msglen);
|
|
output(cstate->unit, outpacket_buf, outlen + DLLHEADERLEN);
|
|
|
|
CHAPDEBUG((LOG_INFO, "ChapSendStatus: Sent code %d, id %d.", code,
|
|
cstate->chal_id));
|
|
}
|
|
|
|
/*
|
|
* ChapGenChallenge is used to generate a pseudo-random challenge string of
|
|
* a pseudo-random length between min_len and max_len. The challenge
|
|
* string and its length are stored in *cstate, and various other fields of
|
|
* *cstate are initialized.
|
|
*/
|
|
|
|
static void
|
|
ChapGenChallenge(cstate)
|
|
chap_state *cstate;
|
|
{
|
|
int chal_len;
|
|
u_char *ptr = cstate->challenge;
|
|
unsigned int i;
|
|
|
|
/* pick a random challenge length between MIN_CHALLENGE_LENGTH and
|
|
MAX_CHALLENGE_LENGTH */
|
|
chal_len = (unsigned) ((drand48() *
|
|
(MAX_CHALLENGE_LENGTH - MIN_CHALLENGE_LENGTH)) +
|
|
MIN_CHALLENGE_LENGTH);
|
|
cstate->chal_len = chal_len;
|
|
cstate->chal_id = ++cstate->id;
|
|
cstate->chal_transmits = 0;
|
|
|
|
/* generate a random string */
|
|
for (i = 0; i < chal_len; i++ )
|
|
*ptr++ = (char) (drand48() * 0xff);
|
|
}
|
|
|
|
/*
|
|
* ChapSendResponse - send a response packet with values as specified
|
|
* in *cstate.
|
|
*/
|
|
/* ARGSUSED */
|
|
static void
|
|
ChapSendResponse(cstate)
|
|
chap_state *cstate;
|
|
{
|
|
u_char *outp;
|
|
int outlen, md_len, name_len;
|
|
|
|
md_len = cstate->resp_length;
|
|
name_len = strlen(cstate->resp_name);
|
|
outlen = CHAP_HEADERLEN + sizeof (u_char) + md_len + name_len;
|
|
outp = outpacket_buf;
|
|
|
|
MAKEHEADER(outp, CHAP);
|
|
|
|
PUTCHAR(CHAP_RESPONSE, outp); /* we are a response */
|
|
PUTCHAR(cstate->resp_id, outp); /* copy id from challenge packet */
|
|
PUTSHORT(outlen, outp); /* packet length */
|
|
|
|
PUTCHAR(md_len, outp); /* length of MD */
|
|
BCOPY(cstate->response, outp, md_len); /* copy MD to buffer */
|
|
INCPTR(md_len, outp);
|
|
|
|
BCOPY(cstate->resp_name, outp, name_len); /* append our name */
|
|
|
|
/* send the packet */
|
|
output(cstate->unit, outpacket_buf, outlen + DLLHEADERLEN);
|
|
|
|
cstate->clientstate = CHAPCS_RESPONSE;
|
|
TIMEOUT(ChapResponseTimeout, (caddr_t) cstate, cstate->timeouttime);
|
|
++cstate->resp_transmits;
|
|
}
|
|
|
|
/*
|
|
* ChapPrintPkt - print the contents of a CHAP packet.
|
|
*/
|
|
char *ChapCodenames[] = {
|
|
"Challenge", "Response", "Success", "Failure"
|
|
};
|
|
|
|
int
|
|
ChapPrintPkt(p, plen, printer, arg)
|
|
u_char *p;
|
|
int plen;
|
|
void (*printer) __ARGS((void *, char *, ...));
|
|
void *arg;
|
|
{
|
|
int code, id, len;
|
|
int clen, nlen;
|
|
u_char x;
|
|
|
|
if (plen < CHAP_HEADERLEN)
|
|
return 0;
|
|
GETCHAR(code, p);
|
|
GETCHAR(id, p);
|
|
GETSHORT(len, p);
|
|
if (len < CHAP_HEADERLEN || len > plen)
|
|
return 0;
|
|
|
|
if (code >= 1 && code <= sizeof(ChapCodenames) / sizeof(char *))
|
|
printer(arg, " %s", ChapCodenames[code-1]);
|
|
else
|
|
printer(arg, " code=0x%x", code);
|
|
printer(arg, " id=0x%x", id);
|
|
len -= CHAP_HEADERLEN;
|
|
switch (code) {
|
|
case CHAP_CHALLENGE:
|
|
case CHAP_RESPONSE:
|
|
if (len < 1)
|
|
break;
|
|
clen = p[0];
|
|
if (len < clen + 1)
|
|
break;
|
|
++p;
|
|
nlen = len - clen - 1;
|
|
printer(arg, " <");
|
|
for (; clen > 0; --clen) {
|
|
GETCHAR(x, p);
|
|
printer(arg, "%.2x", x);
|
|
}
|
|
printer(arg, ">, name = ");
|
|
print_string((char *)p, nlen, printer, arg);
|
|
break;
|
|
case CHAP_FAILURE:
|
|
case CHAP_SUCCESS:
|
|
printer(arg, " ");
|
|
print_string((char *)p, len, printer, arg);
|
|
break;
|
|
default:
|
|
for (clen = len; clen > 0; --clen) {
|
|
GETCHAR(x, p);
|
|
printer(arg, " %.2x", x);
|
|
}
|
|
}
|
|
|
|
return len + CHAP_HEADERLEN;
|
|
}
|
|
|
|
#ifdef NO_DRAND48
|
|
|
|
double drand48()
|
|
{
|
|
return (double)random() / (double)0x7fffffffL; /* 2**31-1 */
|
|
}
|
|
|
|
void srand48(seedval)
|
|
long seedval;
|
|
{
|
|
srand((int)seedval);
|
|
}
|
|
|
|
#endif
|