1 /*** WARNING - THIS HAS NEVER BEEN FINISHED ***/
2 /*****************************************************************************
3 * chap.c - Network Challenge Handshake Authentication Protocol program file.
5 * Copyright (c) 2003 by Marc Boucher, Services Informatiques (MBSI) inc.
6 * portions Copyright (c) 1997 by Global Election Systems Inc.
8 * The authors hereby grant permission to use, copy, modify, distribute,
9 * and license this software and its documentation for any purpose, provided
10 * that existing copyright notices are retained in all copies and that this
11 * notice and the following disclaimer are included verbatim in any
12 * distributions. No written agreement, license, or royalty fee is required
13 * for any of the authorized uses.
15 * THIS SOFTWARE IS PROVIDED BY THE CONTRIBUTORS *AS IS* AND ANY EXPRESS OR
16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18 * IN NO EVENT SHALL THE CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 ******************************************************************************
29 * 03-01-01 Marc Boucher <marc@mbsi.ca>
31 * 97-12-04 Guy Lancaster <lancasterg@acm.org>, Global Election Systems Inc.
32 * Original based on BSD chap.c.
33 *****************************************************************************/
35 * chap.c - Challenge Handshake Authentication Protocol.
37 * Copyright (c) 1993 The Australian National University.
38 * All rights reserved.
40 * Redistribution and use in source and binary forms are permitted
41 * provided that the above copyright notice and this paragraph are
42 * duplicated in all such forms and that any documentation,
43 * advertising materials, and other materials related to such
44 * distribution and use acknowledge that the software was developed
45 * by the Australian National University. The name of the University
46 * may not be used to endorse or promote products derived from this
47 * software without specific prior written permission.
48 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
49 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
50 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
52 * Copyright (c) 1991 Gregory M. Christy.
53 * All rights reserved.
55 * Redistribution and use in source and binary forms are permitted
56 * provided that the above copyright notice and this paragraph are
57 * duplicated in all such forms and that any documentation,
58 * advertising materials, and other materials related to such
59 * distribution and use acknowledge that the software was developed
60 * by Gregory M. Christy. The name of the author may not be used to
61 * endorse or promote products derived from this software without
62 * specific prior written permission.
64 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
65 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
66 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
71 #if PPP_SUPPORT /* don't build if not configured for use in lwipopts.h */
73 #if CHAP_SUPPORT /* don't build if not configured for use in lwipopts.h */
87 /*************************/
88 /*** LOCAL DEFINITIONS ***/
89 /*************************/
92 /************************/
93 /*** LOCAL DATA TYPES ***/
94 /************************/
97 /***********************************/
98 /*** LOCAL FUNCTION DECLARATIONS ***/
99 /***********************************/
101 * Protocol entry points.
103 static void ChapInit (int);
104 static void ChapLowerUp (int);
105 static void ChapLowerDown (int);
106 static void ChapInput (int, u_char
*, int);
107 static void ChapProtocolReject (int);
109 static int ChapPrintPkt (u_char
*, int, void (*) (void *, char *, ...), void *);
112 static void ChapChallengeTimeout (void *);
113 static void ChapResponseTimeout (void *);
114 static void ChapReceiveChallenge (chap_state
*, u_char
*, int, int);
115 static void ChapRechallenge (void *);
116 static void ChapReceiveResponse (chap_state
*, u_char
*, int, int);
117 static void ChapReceiveSuccess(chap_state
*cstate
, u_char
*inp
, u_char id
, int len
);
118 static void ChapReceiveFailure(chap_state
*cstate
, u_char
*inp
, u_char id
, int len
);
119 static void ChapSendStatus (chap_state
*, int);
120 static void ChapSendChallenge (chap_state
*);
121 static void ChapSendResponse (chap_state
*);
122 static void ChapGenChallenge (chap_state
*);
125 /******************************/
126 /*** PUBLIC DATA STRUCTURES ***/
127 /******************************/
128 chap_state chap
[NUM_PPP
]; /* CHAP state; one for each unit */
130 struct protent chap_protent
= {
153 /***********************************/
154 /*** PUBLIC FUNCTION DEFINITIONS ***/
155 /***********************************/
157 * ChapAuthWithPeer - Authenticate us with our peer (start client).
161 ChapAuthWithPeer(int unit
, char *our_name
, int digest
)
163 chap_state
*cstate
= &chap
[unit
];
165 cstate
->resp_name
= our_name
;
166 cstate
->resp_type
= digest
;
168 if (cstate
->clientstate
== CHAPCS_INITIAL
||
169 cstate
->clientstate
== CHAPCS_PENDING
) {
170 /* lower layer isn't up - wait until later */
171 cstate
->clientstate
= CHAPCS_PENDING
;
176 * We get here as a result of LCP coming up.
177 * So even if CHAP was open before, we will
178 * have to re-authenticate ourselves.
180 cstate
->clientstate
= CHAPCS_LISTEN
;
185 * ChapAuthPeer - Authenticate our peer (start server).
188 ChapAuthPeer(int unit
, char *our_name
, int digest
)
190 chap_state
*cstate
= &chap
[unit
];
192 cstate
->chal_name
= our_name
;
193 cstate
->chal_type
= digest
;
195 if (cstate
->serverstate
== CHAPSS_INITIAL
||
196 cstate
->serverstate
== CHAPSS_PENDING
) {
197 /* lower layer isn't up - wait until later */
198 cstate
->serverstate
= CHAPSS_PENDING
;
202 ChapGenChallenge(cstate
);
203 ChapSendChallenge(cstate
); /* crank it up dude! */
204 cstate
->serverstate
= CHAPSS_INITIAL_CHAL
;
208 /**********************************/
209 /*** LOCAL FUNCTION DEFINITIONS ***/
210 /**********************************/
212 * ChapInit - Initialize a CHAP unit.
217 chap_state
*cstate
= &chap
[unit
];
219 BZERO(cstate
, sizeof(*cstate
));
221 cstate
->clientstate
= CHAPCS_INITIAL
;
222 cstate
->serverstate
= CHAPSS_INITIAL
;
223 cstate
->timeouttime
= CHAP_DEFTIMEOUT
;
224 cstate
->max_transmits
= CHAP_DEFTRANSMITS
;
225 /* random number generator is initialized in magic_init */
230 * ChapChallengeTimeout - Timeout expired on sending challenge.
233 ChapChallengeTimeout(void *arg
)
235 chap_state
*cstate
= (chap_state
*) arg
;
237 /* if we aren't sending challenges, don't worry. then again we */
238 /* probably shouldn't be here either */
239 if (cstate
->serverstate
!= CHAPSS_INITIAL_CHAL
&&
240 cstate
->serverstate
!= CHAPSS_RECHALLENGE
) {
244 if (cstate
->chal_transmits
>= cstate
->max_transmits
) {
245 /* give up on peer */
246 CHAPDEBUG((LOG_ERR
, "Peer failed to respond to CHAP challenge\n"));
247 cstate
->serverstate
= CHAPSS_BADAUTH
;
248 auth_peer_fail(cstate
->unit
, PPP_CHAP
);
252 ChapSendChallenge(cstate
); /* Re-send challenge */
257 * ChapResponseTimeout - Timeout expired on sending response.
260 ChapResponseTimeout(void *arg
)
262 chap_state
*cstate
= (chap_state
*) arg
;
264 /* if we aren't sending a response, don't worry. */
265 if (cstate
->clientstate
!= CHAPCS_RESPONSE
) {
269 ChapSendResponse(cstate
); /* re-send response */
274 * ChapRechallenge - Time to challenge the peer again.
277 ChapRechallenge(void *arg
)
279 chap_state
*cstate
= (chap_state
*) arg
;
281 /* if we aren't sending a response, don't worry. */
282 if (cstate
->serverstate
!= CHAPSS_OPEN
) {
286 ChapGenChallenge(cstate
);
287 ChapSendChallenge(cstate
);
288 cstate
->serverstate
= CHAPSS_RECHALLENGE
;
293 * ChapLowerUp - The lower layer is up.
295 * Start up if we have pending requests.
298 ChapLowerUp(int unit
)
300 chap_state
*cstate
= &chap
[unit
];
302 if (cstate
->clientstate
== CHAPCS_INITIAL
) {
303 cstate
->clientstate
= CHAPCS_CLOSED
;
304 } else if (cstate
->clientstate
== CHAPCS_PENDING
) {
305 cstate
->clientstate
= CHAPCS_LISTEN
;
308 if (cstate
->serverstate
== CHAPSS_INITIAL
) {
309 cstate
->serverstate
= CHAPSS_CLOSED
;
310 } else if (cstate
->serverstate
== CHAPSS_PENDING
) {
311 ChapGenChallenge(cstate
);
312 ChapSendChallenge(cstate
);
313 cstate
->serverstate
= CHAPSS_INITIAL_CHAL
;
319 * ChapLowerDown - The lower layer is down.
321 * Cancel all timeouts.
324 ChapLowerDown(int unit
)
326 chap_state
*cstate
= &chap
[unit
];
328 /* Timeout(s) pending? Cancel if so. */
329 if (cstate
->serverstate
== CHAPSS_INITIAL_CHAL
||
330 cstate
->serverstate
== CHAPSS_RECHALLENGE
) {
331 UNTIMEOUT(ChapChallengeTimeout
, cstate
);
332 } else if (cstate
->serverstate
== CHAPSS_OPEN
333 && cstate
->chal_interval
!= 0) {
334 UNTIMEOUT(ChapRechallenge
, cstate
);
336 if (cstate
->clientstate
== CHAPCS_RESPONSE
) {
337 UNTIMEOUT(ChapResponseTimeout
, cstate
);
339 cstate
->clientstate
= CHAPCS_INITIAL
;
340 cstate
->serverstate
= CHAPSS_INITIAL
;
345 * ChapProtocolReject - Peer doesn't grok CHAP.
348 ChapProtocolReject(int unit
)
350 chap_state
*cstate
= &chap
[unit
];
352 if (cstate
->serverstate
!= CHAPSS_INITIAL
&&
353 cstate
->serverstate
!= CHAPSS_CLOSED
) {
354 auth_peer_fail(unit
, PPP_CHAP
);
356 if (cstate
->clientstate
!= CHAPCS_INITIAL
&&
357 cstate
->clientstate
!= CHAPCS_CLOSED
) {
358 auth_withpeer_fail(unit
, PPP_CHAP
);
360 ChapLowerDown(unit
); /* shutdown chap */
365 * ChapInput - Input CHAP packet.
368 ChapInput(int unit
, u_char
*inpacket
, int packet_len
)
370 chap_state
*cstate
= &chap
[unit
];
376 * Parse header (code, id and length).
377 * If packet too short, drop it.
380 if (packet_len
< CHAP_HEADERLEN
) {
381 CHAPDEBUG((LOG_INFO
, "ChapInput: rcvd short header.\n"));
387 if (len
< CHAP_HEADERLEN
) {
388 CHAPDEBUG((LOG_INFO
, "ChapInput: rcvd illegal length.\n"));
391 if (len
> packet_len
) {
392 CHAPDEBUG((LOG_INFO
, "ChapInput: rcvd short packet.\n"));
395 len
-= CHAP_HEADERLEN
;
398 * Action depends on code (as in fact it usually does :-).
402 ChapReceiveChallenge(cstate
, inp
, id
, len
);
406 ChapReceiveResponse(cstate
, inp
, id
, len
);
410 ChapReceiveFailure(cstate
, inp
, id
, len
);
414 ChapReceiveSuccess(cstate
, inp
, id
, len
);
417 default: /* Need code reject? */
418 CHAPDEBUG((LOG_WARNING
, "Unknown CHAP code (%d) received.\n", code
));
425 * ChapReceiveChallenge - Receive Challenge and send Response.
428 ChapReceiveChallenge(chap_state
*cstate
, u_char
*inp
, int id
, int len
)
433 char secret
[MAXSECRETLEN
];
436 u_char hash
[MD5_SIGNATURE_SIZE
];
438 CHAPDEBUG((LOG_INFO
, "ChapReceiveChallenge: Rcvd id %d.\n", id
));
439 if (cstate
->clientstate
== CHAPCS_CLOSED
||
440 cstate
->clientstate
== CHAPCS_PENDING
) {
441 CHAPDEBUG((LOG_INFO
, "ChapReceiveChallenge: in state %d\n",
442 cstate
->clientstate
));
447 CHAPDEBUG((LOG_INFO
, "ChapReceiveChallenge: rcvd short packet.\n"));
451 GETCHAR(rchallenge_len
, inp
);
452 len
-= sizeof (u_char
) + rchallenge_len
; /* now name field length */
454 CHAPDEBUG((LOG_INFO
, "ChapReceiveChallenge: rcvd short packet.\n"));
458 INCPTR(rchallenge_len
, inp
);
460 if (len
>= sizeof(rhostname
)) {
461 len
= sizeof(rhostname
) - 1;
463 BCOPY(inp
, rhostname
, len
);
464 rhostname
[len
] = '\000';
466 CHAPDEBUG((LOG_INFO
, "ChapReceiveChallenge: received name field '%s'\n", rhostname
));
468 /* Microsoft doesn't send their name back in the PPP packet */
469 if (ppp_settings
.remote_name
[0] != 0 && (ppp_settings
.explicit_remote
|| rhostname
[0] == 0)) {
470 strncpy(rhostname
, ppp_settings
.remote_name
, sizeof(rhostname
));
471 rhostname
[sizeof(rhostname
) - 1] = 0;
472 CHAPDEBUG((LOG_INFO
, "ChapReceiveChallenge: using '%s' as remote name\n", rhostname
));
475 /* get secret for authenticating ourselves with the specified host */
476 if (!get_secret(cstate
->unit
, cstate
->resp_name
, rhostname
, secret
, &secret_len
, 0)) {
477 secret_len
= 0; /* assume null secret if can't find one */
478 CHAPDEBUG((LOG_WARNING
, "No CHAP secret found for authenticating us to %s\n", rhostname
));
481 /* cancel response send timeout if necessary */
482 if (cstate
->clientstate
== CHAPCS_RESPONSE
) {
483 UNTIMEOUT(ChapResponseTimeout
, cstate
);
486 cstate
->resp_id
= id
;
487 cstate
->resp_transmits
= 0;
489 /* generate MD based on negotiated type */
490 switch (cstate
->resp_type
) {
492 case CHAP_DIGEST_MD5
:
494 MD5Update(&mdContext
, &cstate
->resp_id
, 1);
495 MD5Update(&mdContext
, (u_char
*)secret
, secret_len
);
496 MD5Update(&mdContext
, rchallenge
, rchallenge_len
);
497 MD5Final(hash
, &mdContext
);
498 BCOPY(hash
, cstate
->response
, MD5_SIGNATURE_SIZE
);
499 cstate
->resp_length
= MD5_SIGNATURE_SIZE
;
504 ChapMS(cstate
, rchallenge
, rchallenge_len
, secret
, secret_len
);
509 CHAPDEBUG((LOG_INFO
, "unknown digest type %d\n", cstate
->resp_type
));
513 BZERO(secret
, sizeof(secret
));
514 ChapSendResponse(cstate
);
519 * ChapReceiveResponse - Receive and process response.
522 ChapReceiveResponse(chap_state
*cstate
, u_char
*inp
, int id
, int len
)
524 u_char
*remmd
, remmd_len
;
525 int secret_len
, old_state
;
529 char secret
[MAXSECRETLEN
];
530 u_char hash
[MD5_SIGNATURE_SIZE
];
532 CHAPDEBUG((LOG_INFO
, "ChapReceiveResponse: Rcvd id %d.\n", id
));
534 if (cstate
->serverstate
== CHAPSS_CLOSED
||
535 cstate
->serverstate
== CHAPSS_PENDING
) {
536 CHAPDEBUG((LOG_INFO
, "ChapReceiveResponse: in state %d\n",
537 cstate
->serverstate
));
541 if (id
!= cstate
->chal_id
) {
542 return; /* doesn't match ID of last challenge */
546 * If we have received a duplicate or bogus Response,
547 * we have to send the same answer (Success/Failure)
548 * as we did for the first Response we saw.
550 if (cstate
->serverstate
== CHAPSS_OPEN
) {
551 ChapSendStatus(cstate
, CHAP_SUCCESS
);
554 if (cstate
->serverstate
== CHAPSS_BADAUTH
) {
555 ChapSendStatus(cstate
, CHAP_FAILURE
);
560 CHAPDEBUG((LOG_INFO
, "ChapReceiveResponse: rcvd short packet.\n"));
563 GETCHAR(remmd_len
, inp
); /* get length of MD */
564 remmd
= inp
; /* get pointer to MD */
565 INCPTR(remmd_len
, inp
);
567 len
-= sizeof (u_char
) + remmd_len
;
569 CHAPDEBUG((LOG_INFO
, "ChapReceiveResponse: rcvd short packet.\n"));
573 UNTIMEOUT(ChapChallengeTimeout
, cstate
);
575 if (len
>= sizeof(rhostname
)) {
576 len
= sizeof(rhostname
) - 1;
578 BCOPY(inp
, rhostname
, len
);
579 rhostname
[len
] = '\000';
581 CHAPDEBUG((LOG_INFO
, "ChapReceiveResponse: received name field: %s\n", rhostname
));
584 * Get secret for authenticating them with us,
585 * do the hash ourselves, and compare the result.
588 if (!get_secret(cstate
->unit
, rhostname
, cstate
->chal_name
, secret
, &secret_len
, 1)) {
589 /* CHAPDEBUG((LOG_WARNING, TL_CHAP, "No CHAP secret found for authenticating %s\n", rhostname)); */
590 CHAPDEBUG((LOG_WARNING
, "No CHAP secret found for authenticating %s\n",
593 /* generate MD based on negotiated type */
594 switch (cstate
->chal_type
) {
596 case CHAP_DIGEST_MD5
: /* only MD5 is defined for now */
597 if (remmd_len
!= MD5_SIGNATURE_SIZE
) {
598 break; /* it's not even the right length */
601 MD5Update(&mdContext
, &cstate
->chal_id
, 1);
602 MD5Update(&mdContext
, (u_char
*)secret
, secret_len
);
603 MD5Update(&mdContext
, cstate
->challenge
, cstate
->chal_len
);
604 MD5Final(hash
, &mdContext
);
606 /* compare local and remote MDs and send the appropriate status */
607 if (memcmp (hash
, remmd
, MD5_SIGNATURE_SIZE
) == 0) {
608 code
= CHAP_SUCCESS
; /* they are the same! */
613 CHAPDEBUG((LOG_INFO
, "unknown digest type %d\n", cstate
->chal_type
));
617 BZERO(secret
, sizeof(secret
));
618 ChapSendStatus(cstate
, code
);
620 if (code
== CHAP_SUCCESS
) {
621 old_state
= cstate
->serverstate
;
622 cstate
->serverstate
= CHAPSS_OPEN
;
623 if (old_state
== CHAPSS_INITIAL_CHAL
) {
624 auth_peer_success(cstate
->unit
, PPP_CHAP
, rhostname
, len
);
626 if (cstate
->chal_interval
!= 0) {
627 TIMEOUT(ChapRechallenge
, cstate
, cstate
->chal_interval
);
630 CHAPDEBUG((LOG_ERR
, "CHAP peer authentication failed\n"));
631 cstate
->serverstate
= CHAPSS_BADAUTH
;
632 auth_peer_fail(cstate
->unit
, PPP_CHAP
);
637 * ChapReceiveSuccess - Receive Success
640 ChapReceiveSuccess(chap_state
*cstate
, u_char
*inp
, u_char id
, int len
)
643 LWIP_UNUSED_ARG(inp
);
645 CHAPDEBUG((LOG_INFO
, "ChapReceiveSuccess: Rcvd id %d.\n", id
));
647 if (cstate
->clientstate
== CHAPCS_OPEN
) {
648 /* presumably an answer to a duplicate response */
652 if (cstate
->clientstate
!= CHAPCS_RESPONSE
) {
653 /* don't know what this is */
654 CHAPDEBUG((LOG_INFO
, "ChapReceiveSuccess: in state %d\n", cstate
->clientstate
));
658 UNTIMEOUT(ChapResponseTimeout
, cstate
);
667 cstate
->clientstate
= CHAPCS_OPEN
;
669 auth_withpeer_success(cstate
->unit
, PPP_CHAP
);
674 * ChapReceiveFailure - Receive failure.
677 ChapReceiveFailure(chap_state
*cstate
, u_char
*inp
, u_char id
, int len
)
680 LWIP_UNUSED_ARG(inp
);
682 CHAPDEBUG((LOG_INFO
, "ChapReceiveFailure: Rcvd id %d.\n", id
));
684 if (cstate
->clientstate
!= CHAPCS_RESPONSE
) {
685 /* don't know what this is */
686 CHAPDEBUG((LOG_INFO
, "ChapReceiveFailure: in state %d\n", cstate
->clientstate
));
690 UNTIMEOUT(ChapResponseTimeout
, cstate
);
699 CHAPDEBUG((LOG_ERR
, "CHAP authentication failed\n"));
700 auth_withpeer_fail(cstate
->unit
, PPP_CHAP
);
705 * ChapSendChallenge - Send an Authenticate challenge.
708 ChapSendChallenge(chap_state
*cstate
)
711 int chal_len
, name_len
;
714 chal_len
= cstate
->chal_len
;
715 name_len
= strlen(cstate
->chal_name
);
716 outlen
= CHAP_HEADERLEN
+ sizeof (u_char
) + chal_len
+ name_len
;
717 outp
= outpacket_buf
[cstate
->unit
];
719 MAKEHEADER(outp
, PPP_CHAP
); /* paste in a CHAP header */
721 PUTCHAR(CHAP_CHALLENGE
, outp
);
722 PUTCHAR(cstate
->chal_id
, outp
);
723 PUTSHORT(outlen
, outp
);
725 PUTCHAR(chal_len
, outp
); /* put length of challenge */
726 BCOPY(cstate
->challenge
, outp
, chal_len
);
727 INCPTR(chal_len
, outp
);
729 BCOPY(cstate
->chal_name
, outp
, name_len
); /* append hostname */
731 pppWrite(cstate
->unit
, outpacket_buf
[cstate
->unit
], outlen
+ PPP_HDRLEN
);
733 CHAPDEBUG((LOG_INFO
, "ChapSendChallenge: Sent id %d.\n", cstate
->chal_id
));
735 TIMEOUT(ChapChallengeTimeout
, cstate
, cstate
->timeouttime
);
736 ++cstate
->chal_transmits
;
741 * ChapSendStatus - Send a status response (ack or nak).
744 ChapSendStatus(chap_state
*cstate
, int code
)
750 if (code
== CHAP_SUCCESS
) {
751 strcpy(msg
, "Welcome!");
753 strcpy(msg
, "I don't like you. Go 'way.");
755 msglen
= strlen(msg
);
757 outlen
= CHAP_HEADERLEN
+ msglen
;
758 outp
= outpacket_buf
[cstate
->unit
];
760 MAKEHEADER(outp
, PPP_CHAP
); /* paste in a header */
763 PUTCHAR(cstate
->chal_id
, outp
);
764 PUTSHORT(outlen
, outp
);
765 BCOPY(msg
, outp
, msglen
);
766 pppWrite(cstate
->unit
, outpacket_buf
[cstate
->unit
], outlen
+ PPP_HDRLEN
);
768 CHAPDEBUG((LOG_INFO
, "ChapSendStatus: Sent code %d, id %d.\n", code
, cstate
->chal_id
));
772 * ChapGenChallenge is used to generate a pseudo-random challenge string of
773 * a pseudo-random length between min_len and max_len. The challenge
774 * string and its length are stored in *cstate, and various other fields of
775 * *cstate are initialized.
779 ChapGenChallenge(chap_state
*cstate
)
782 u_char
*ptr
= cstate
->challenge
;
785 /* pick a random challenge length between MIN_CHALLENGE_LENGTH and
786 MAX_CHALLENGE_LENGTH */
787 chal_len
= (unsigned)
789 (MAX_CHALLENGE_LENGTH
- MIN_CHALLENGE_LENGTH
)) >> 16)
790 + MIN_CHALLENGE_LENGTH
);
791 cstate
->chal_len
= chal_len
;
792 cstate
->chal_id
= ++cstate
->id
;
793 cstate
->chal_transmits
= 0;
795 /* generate a random string */
796 for (i
= 0; i
< chal_len
; i
++ ) {
797 *ptr
++ = (char) (magic() & 0xff);
802 * ChapSendResponse - send a response packet with values as specified
807 ChapSendResponse(chap_state
*cstate
)
810 int outlen
, md_len
, name_len
;
812 md_len
= cstate
->resp_length
;
813 name_len
= strlen(cstate
->resp_name
);
814 outlen
= CHAP_HEADERLEN
+ sizeof (u_char
) + md_len
+ name_len
;
815 outp
= outpacket_buf
[cstate
->unit
];
817 MAKEHEADER(outp
, PPP_CHAP
);
819 PUTCHAR(CHAP_RESPONSE
, outp
); /* we are a response */
820 PUTCHAR(cstate
->resp_id
, outp
); /* copy id from challenge packet */
821 PUTSHORT(outlen
, outp
); /* packet length */
823 PUTCHAR(md_len
, outp
); /* length of MD */
824 BCOPY(cstate
->response
, outp
, md_len
); /* copy MD to buffer */
825 INCPTR(md_len
, outp
);
827 BCOPY(cstate
->resp_name
, outp
, name_len
); /* append our name */
829 /* send the packet */
830 pppWrite(cstate
->unit
, outpacket_buf
[cstate
->unit
], outlen
+ PPP_HDRLEN
);
832 cstate
->clientstate
= CHAPCS_RESPONSE
;
833 TIMEOUT(ChapResponseTimeout
, cstate
, cstate
->timeouttime
);
834 ++cstate
->resp_transmits
;
838 static char *ChapCodenames
[] = {
839 "Challenge", "Response", "Success", "Failure"
842 * ChapPrintPkt - print the contents of a CHAP packet.
845 ChapPrintPkt( u_char
*p
, int plen
, void (*printer
) (void *, char *, ...), void *arg
)
851 if (plen
< CHAP_HEADERLEN
) {
857 if (len
< CHAP_HEADERLEN
|| len
> plen
) {
860 if (code
>= 1 && code
<= sizeof(ChapCodenames
) / sizeof(char *)) {
861 printer(arg
, " %s", ChapCodenames
[code
-1]);
863 printer(arg
, " code=0x%x", code
);
865 printer(arg
, " id=0x%x", id
);
866 len
-= CHAP_HEADERLEN
;
874 if (len
< clen
+ 1) {
878 nlen
= len
- clen
- 1;
880 for (; clen
> 0; --clen
) {
882 printer(arg
, "%.2x", x
);
884 printer(arg
, ">, name = %.*Z", nlen
, p
);
888 printer(arg
, " %.*Z", len
, p
);
891 for (clen
= len
; clen
> 0; --clen
) {
893 printer(arg
, " %.2x", x
);
897 return len
+ CHAP_HEADERLEN
;
901 #endif /* CHAP_SUPPORT */
903 #endif /* PPP_SUPPORT */