[openssh.git] / auth-chall.c

/*
 * 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
59c97189	1	/*
f3c7c613	2	* Copyright (c) 2001 Markus Friedl. All rights reserved.
59c97189	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"
59c97189	26
59c97189	27	#include "auth.h"
af774732	28	#include "log.h"
5ba55ada	29	#include "xmalloc.h"
c384a74c	30	#include "servconf.h"
59c97189	31
5ba55ada	32	/* limited protocol v1 interface to kbd-interactive authentication */
af774732	33
5ba55ada	34	extern KbdintDevice *devices[];
5ba55ada	35	static KbdintDevice *device;
c384a74c	36	extern ServerOptions options;
6005a40c	37
59c97189	38	char *
5ba55ada	39	get_challenge(Authctxt *authctxt)
59c97189	40	{
5ba55ada	41	char challenge, name, info, *prompts;
	42	u_int i, numprompts;
	43	u_int *echo_on;
	44
c384a74c	45	#ifdef USE_PAM
	46	if (!options.use_pam)
	47	remove_kbdint_device("pam");
	48	#endif
	49
5ba55ada	50	device = devices[0]; /* we always use the 1st device for protocol 1 */
5ba55ada	51	if (device == NULL)
59c97189	52	return NULL;
5ba55ada	53	if ((authctxt->kbdintctxt = device->init_ctx(authctxt)) == NULL)
	54	return NULL;
	55	if (device->query(authctxt->kbdintctxt, &name, &info,
	56	&numprompts, &prompts, &echo_on)) {
	57	device->free_ctx(authctxt->kbdintctxt);
	58	authctxt->kbdintctxt = NULL;
	59	return NULL;
	60	}
	61	if (numprompts < 1)
	62	fatal("get_challenge: numprompts < 1");
	63	challenge = xstrdup(prompts[0]);
	64	for (i = 0; i < numprompts; i++)
	65	xfree(prompts[i]);
	66	xfree(prompts);
	67	xfree(name);
	68	xfree(echo_on);
	69	xfree(info);
	70
	71	return (challenge);
59c97189	72	}
59c97189	73	int
5ba55ada	74	verify_response(Authctxt authctxt, const char response)
59c97189	75	{
85a68682	76	char resp[1], name, info, *prompts;
	77	u_int i, numprompts, *echo_on;
	78	int authenticated = 0;
5ba55ada	79
	80	if (device == NULL)
	81	return 0;
	82	if (authctxt->kbdintctxt == NULL)
	83	return 0;
	84	resp[0] = (char *)response;
85a68682	85	switch (device->respond(authctxt->kbdintctxt, 1, resp)) {
	86	case 0: /* Success */
	87	authenticated = 1;
	88	break;
	89	case 1: /* Postponed - retry with empty query for PAM */
	90	if ((device->query(authctxt->kbdintctxt, &name, &info,
	91	&numprompts, &prompts, &echo_on)) != 0)
	92	break;
aff51935	93	if (numprompts == 0 &&
85a68682	94	device->respond(authctxt->kbdintctxt, 0, resp) == 0)
85a68682	95	authenticated = 1;
05114c74	96
85a68682	97	for (i = 0; i < numprompts; i++)
	98	xfree(prompts[i]);
	99	xfree(prompts);
	100	xfree(name);
	101	xfree(echo_on);
	102	xfree(info);
	103	break;
05114c74	104	}
5ba55ada	105	device->free_ctx(authctxt->kbdintctxt);
5ba55ada	106	authctxt->kbdintctxt = NULL;
85a68682	107	return authenticated;
59c97189	108	}
05114c74	109	void
	110	abandon_challenge_response(Authctxt *authctxt)
	111	{
	112	if (authctxt->kbdintctxt != NULL) {
	113	device->free_ctx(authctxt->kbdintctxt);
	114	authctxt->kbdintctxt = NULL;
	115	}
	116	}