xref: /titanic_50/usr/src/cmd/ssh/sshd/auth-chall.c (revision 1ae0874509b6811fdde1dfd46f0d93fd09867a3f)
1 /*
2  * Copyright (c) 2001 Markus Friedl.  All rights reserved.
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  * 1. Redistributions of source code must retain the above copyright
8  *    notice, this list of conditions and the following disclaimer.
9  * 2. Redistributions in binary form must reproduce the above copyright
10  *    notice, this list of conditions and the following disclaimer in the
11  *    documentation and/or other materials provided with the distribution.
12  *
13  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
14  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
15  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
16  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
17  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
18  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
19  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
20  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
21  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
22  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
23  */
24 
25 #include "includes.h"
26 RCSID("$OpenBSD: auth-chall.c,v 1.8 2001/05/18 14:13:28 markus Exp $");
27 
28 #pragma ident	"%Z%%M%	%I%	%E% SMI"
29 
30 #include "auth.h"
31 #include "log.h"
32 #include "xmalloc.h"
33 
34 /* limited protocol v1 interface to kbd-interactive authentication */
35 
36 extern KbdintDevice *devices[];
37 static KbdintDevice *device;
38 
39 char *
40 get_challenge(Authctxt *authctxt)
41 {
42 	char *challenge, *name, *info, **prompts;
43 	u_int i, numprompts;
44 	u_int *echo_on;
45 
46 	device = devices[0]; /* we always use the 1st device for protocol 1 */
47 	if (device == NULL)
48 		return NULL;
49 	if ((authctxt->kbdintctxt = device->init_ctx(authctxt)) == NULL)
50 		return NULL;
51 	if (device->query(authctxt->kbdintctxt, &name, &info,
52 	    &numprompts, &prompts, &echo_on)) {
53 		device->free_ctx(authctxt->kbdintctxt);
54 		authctxt->kbdintctxt = NULL;
55 		return NULL;
56 	}
57 	if (numprompts < 1)
58 		fatal("get_challenge: numprompts < 1");
59 	challenge = xstrdup(prompts[0]);
60 	for (i = 0; i < numprompts; i++)
61 		xfree(prompts[i]);
62 	xfree(prompts);
63 	xfree(name);
64 	xfree(echo_on);
65 	xfree(info);
66 
67 	return (challenge);
68 }
69 int
70 verify_response(Authctxt *authctxt, const char *response)
71 {
72 	char *resp[1];
73 	int res;
74 
75 	if (device == NULL)
76 		return 0;
77 	if (authctxt->kbdintctxt == NULL)
78 		return 0;
79 	resp[0] = (char *)response;
80 	res = device->respond(authctxt->kbdintctxt, 1, resp);
81 	device->free_ctx(authctxt->kbdintctxt);
82 	authctxt->kbdintctxt = NULL;
83 	return res ? 0 : 1;
84 }
85