[openssh.git] / auth-chall.c

/* $OpenBSD: auth-chall.c,v 1.11 2006/03/25 13:17:01 djm Exp $ */
/*
 * Copyright (c) 2001 Markus Friedl.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include "includes.h"

#include "auth.h"
#include "log.h"
#include "xmalloc.h"
#include "servconf.h"

/* limited protocol v1 interface to kbd-interactive authentication */

extern KbdintDevice *devices[];
static KbdintDevice *device;
extern ServerOptions options;

char *
get_challenge(Authctxt *authctxt)
{
	char *challenge, *name, *info, **prompts;
	u_int i, numprompts;
	u_int *echo_on;

#ifdef USE_PAM
	if (!options.use_pam)
		remove_kbdint_device("pam");
#endif

	device = devices[0]; /* we always use the 1st device for protocol 1 */
	if (device == NULL)
		return NULL;
	if ((authctxt->kbdintctxt = device->init_ctx(authctxt)) == NULL)
		return NULL;
	if (device->query(authctxt->kbdintctxt, &name, &info,
	    &numprompts, &prompts, &echo_on)) {
		device->free_ctx(authctxt->kbdintctxt);
		authctxt->kbdintctxt = NULL;
		return NULL;
	}
	if (numprompts < 1)
		fatal("get_challenge: numprompts < 1");
	challenge = xstrdup(prompts[0]);
	for (i = 0; i < numprompts; i++)
		xfree(prompts[i]);
	xfree(prompts);
	xfree(name);
	xfree(echo_on);
	xfree(info);

	return (challenge);
}
int
verify_response(Authctxt *authctxt, const char *response)
{
	char *resp[1], *name, *info, **prompts;
	u_int i, numprompts, *echo_on;
	int authenticated = 0;

	if (device == NULL)
		return 0;
	if (authctxt->kbdintctxt == NULL)
		return 0;
	resp[0] = (char *)response;
	switch (device->respond(authctxt->kbdintctxt, 1, resp)) {
	case 0: /* Success */
		authenticated = 1;
		break;
	case 1: /* Postponed - retry with empty query for PAM */
		if ((device->query(authctxt->kbdintctxt, &name, &info,
		    &numprompts, &prompts, &echo_on)) != 0)
			break;
		if (numprompts == 0 &&
		    device->respond(authctxt->kbdintctxt, 0, resp) == 0)
			authenticated = 1;

		for (i = 0; i < numprompts; i++)
			xfree(prompts[i]);
		xfree(prompts);
		xfree(name);
		xfree(echo_on);
		xfree(info);
		break;
	}
	device->free_ctx(authctxt->kbdintctxt);
	authctxt->kbdintctxt = NULL;
	return authenticated;
}
void
abandon_challenge_response(Authctxt *authctxt)
{
	if (authctxt->kbdintctxt != NULL) {
		device->free_ctx(authctxt->kbdintctxt);
		authctxt->kbdintctxt = NULL;
	}
}
Commit	Line	Data
c1cb7bae	1	/* $OpenBSD: auth-chall.c,v 1.11 2006/03/25 13:17:01 djm Exp $ */
59c97189	2	/*
f3c7c613	3	* Copyright (c) 2001 Markus Friedl. All rights reserved.
59c97189	4	*
	5	* Redistribution and use in source and binary forms, with or without
	6	* modification, are permitted provided that the following conditions
	7	* are met:
	8	* 1. Redistributions of source code must retain the above copyright
	9	* notice, this list of conditions and the following disclaimer.
	10	* 2. Redistributions in binary form must reproduce the above copyright
	11	* notice, this list of conditions and the following disclaimer in the
	12	* documentation and/or other materials provided with the distribution.
	13	*
	14	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
	15	* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
	16	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
	17	* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
	18	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
	19	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
	20	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
	21	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
	22	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
	23	* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
	24	*/
	25
	26	#include "includes.h"
59c97189	27
59c97189	28	#include "auth.h"
af774732	29	#include "log.h"
5ba55ada	30	#include "xmalloc.h"
c384a74c	31	#include "servconf.h"
59c97189	32
5ba55ada	33	/* limited protocol v1 interface to kbd-interactive authentication */
af774732	34
5ba55ada	35	extern KbdintDevice *devices[];
5ba55ada	36	static KbdintDevice *device;
c384a74c	37	extern ServerOptions options;
6005a40c	38
59c97189	39	char *
5ba55ada	40	get_challenge(Authctxt *authctxt)
59c97189	41	{
5ba55ada	42	char challenge, name, info, *prompts;
	43	u_int i, numprompts;
	44	u_int *echo_on;
	45
c384a74c	46	#ifdef USE_PAM
	47	if (!options.use_pam)
	48	remove_kbdint_device("pam");
	49	#endif
	50
5ba55ada	51	device = devices[0]; /* we always use the 1st device for protocol 1 */
5ba55ada	52	if (device == NULL)
59c97189	53	return NULL;
5ba55ada	54	if ((authctxt->kbdintctxt = device->init_ctx(authctxt)) == NULL)
	55	return NULL;
	56	if (device->query(authctxt->kbdintctxt, &name, &info,
	57	&numprompts, &prompts, &echo_on)) {
	58	device->free_ctx(authctxt->kbdintctxt);
	59	authctxt->kbdintctxt = NULL;
	60	return NULL;
	61	}
	62	if (numprompts < 1)
	63	fatal("get_challenge: numprompts < 1");
	64	challenge = xstrdup(prompts[0]);
	65	for (i = 0; i < numprompts; i++)
	66	xfree(prompts[i]);
	67	xfree(prompts);
	68	xfree(name);
	69	xfree(echo_on);
	70	xfree(info);
	71
	72	return (challenge);
59c97189	73	}
59c97189	74	int
5ba55ada	75	verify_response(Authctxt authctxt, const char response)
59c97189	76	{
85a68682	77	char resp[1], name, info, *prompts;
	78	u_int i, numprompts, *echo_on;
	79	int authenticated = 0;
5ba55ada	80
	81	if (device == NULL)
	82	return 0;
	83	if (authctxt->kbdintctxt == NULL)
	84	return 0;
	85	resp[0] = (char *)response;
85a68682	86	switch (device->respond(authctxt->kbdintctxt, 1, resp)) {
	87	case 0: /* Success */
	88	authenticated = 1;
	89	break;
	90	case 1: /* Postponed - retry with empty query for PAM */
	91	if ((device->query(authctxt->kbdintctxt, &name, &info,
	92	&numprompts, &prompts, &echo_on)) != 0)
	93	break;
aff51935	94	if (numprompts == 0 &&
85a68682	95	device->respond(authctxt->kbdintctxt, 0, resp) == 0)
85a68682	96	authenticated = 1;
05114c74	97
85a68682	98	for (i = 0; i < numprompts; i++)
	99	xfree(prompts[i]);
	100	xfree(prompts);
	101	xfree(name);
	102	xfree(echo_on);
	103	xfree(info);
	104	break;
05114c74	105	}
5ba55ada	106	device->free_ctx(authctxt->kbdintctxt);
5ba55ada	107	authctxt->kbdintctxt = NULL;
85a68682	108	return authenticated;
59c97189	109	}
05114c74	110	void
	111	abandon_challenge_response(Authctxt *authctxt)
	112	{
	113	if (authctxt->kbdintctxt != NULL) {
	114	device->free_ctx(authctxt->kbdintctxt);
	115	authctxt->kbdintctxt = NULL;
	116	}
	117	}