[gssapi-openssh.git] / openssh / auth-chall.c

/* $OpenBSD: auth-chall.c,v 1.12 2006/08/03 03:34:41 deraadt 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 <sys/types.h>

#include <stdarg.h>

#include "xmalloc.h"
#include "key.h"
#include "hostfile.h"
#include "auth.h"
#include "log.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
9108f8d9	1	/* $OpenBSD: auth-chall.c,v 1.12 2006/08/03 03:34:41 deraadt Exp $ */
3c0ef626	2	/*
	3	* Copyright (c) 2001 Markus Friedl. All rights reserved.
	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"
3c0ef626	27
9108f8d9	28	#include <sys/types.h>
	29
	30	#include <stdarg.h>
	31
	32	#include "xmalloc.h"
	33	#include "key.h"
	34	#include "hostfile.h"
3c0ef626	35	#include "auth.h"
3c0ef626	36	#include "log.h"
996d5e62	37	#include "servconf.h"
3c0ef626	38
	39	/* limited protocol v1 interface to kbd-interactive authentication */
	40
	41	extern KbdintDevice *devices[];
	42	static KbdintDevice *device;
996d5e62	43	extern ServerOptions options;
3c0ef626	44
	45	char *
	46	get_challenge(Authctxt *authctxt)
	47	{
	48	char challenge, name, info, *prompts;
	49	u_int i, numprompts;
	50	u_int *echo_on;
	51
996d5e62	52	#ifdef USE_PAM
	53	if (!options.use_pam)
	54	remove_kbdint_device("pam");
	55	#endif
	56
3c0ef626	57	device = devices[0]; /* we always use the 1st device for protocol 1 */
	58	if (device == NULL)
	59	return NULL;
	60	if ((authctxt->kbdintctxt = device->init_ctx(authctxt)) == NULL)
	61	return NULL;
	62	if (device->query(authctxt->kbdintctxt, &name, &info,
	63	&numprompts, &prompts, &echo_on)) {
	64	device->free_ctx(authctxt->kbdintctxt);
	65	authctxt->kbdintctxt = NULL;
	66	return NULL;
	67	}
	68	if (numprompts < 1)
	69	fatal("get_challenge: numprompts < 1");
	70	challenge = xstrdup(prompts[0]);
	71	for (i = 0; i < numprompts; i++)
	72	xfree(prompts[i]);
	73	xfree(prompts);
	74	xfree(name);
	75	xfree(echo_on);
	76	xfree(info);
	77
	78	return (challenge);
	79	}
	80	int
	81	verify_response(Authctxt authctxt, const char response)
	82	{
cdd66111	83	char resp[1], name, info, *prompts;
	84	u_int i, numprompts, *echo_on;
	85	int authenticated = 0;
3c0ef626	86
	87	if (device == NULL)
	88	return 0;
	89	if (authctxt->kbdintctxt == NULL)
	90	return 0;
	91	resp[0] = (char *)response;
cdd66111	92	switch (device->respond(authctxt->kbdintctxt, 1, resp)) {
	93	case 0: /* Success */
	94	authenticated = 1;
	95	break;
	96	case 1: /* Postponed - retry with empty query for PAM */
	97	if ((device->query(authctxt->kbdintctxt, &name, &info,
	98	&numprompts, &prompts, &echo_on)) != 0)
	99	break;
	100	if (numprompts == 0 &&
	101	device->respond(authctxt->kbdintctxt, 0, resp) == 0)
	102	authenticated = 1;
0fff78ff	103
cdd66111	104	for (i = 0; i < numprompts; i++)
	105	xfree(prompts[i]);
	106	xfree(prompts);
	107	xfree(name);
	108	xfree(echo_on);
	109	xfree(info);
	110	break;
0fff78ff	111	}
3c0ef626	112	device->free_ctx(authctxt->kbdintctxt);
3c0ef626	113	authctxt->kbdintctxt = NULL;
cdd66111	114	return authenticated;
3c0ef626	115	}
0fff78ff	116	void
	117	abandon_challenge_response(Authctxt *authctxt)
	118	{
	119	if (authctxt->kbdintctxt != NULL) {
	120	device->free_ctx(authctxt->kbdintctxt);
	121	authctxt->kbdintctxt = NULL;
	122	}
	123	}