[gssapi-openssh.git] / openssh / auth2.c

/*
 * Copyright (c) 2000 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"
RCSID("$OpenBSD: auth2.c,v 1.102 2003/08/26 09:58:43 markus Exp $");

#include "ssh2.h"
#include "xmalloc.h"
#include "packet.h"
#include "log.h"
#include "servconf.h"
#include "auth.h"
#include "dispatch.h"
#include "pathnames.h"
#include "monitor_wrap.h"

#ifdef GSSAPI
#include "ssh-gss.h"
#endif

/* import */
extern ServerOptions options;
extern u_char *session_id2;
extern u_int session_id2_len;

Authctxt *x_authctxt = NULL;

/* methods */

extern Authmethod method_none;
extern Authmethod method_pubkey;
extern Authmethod method_passwd;
extern Authmethod method_kbdint;
extern Authmethod method_hostbased;
#ifdef GSSAPI
extern Authmethod method_external;
extern Authmethod method_gssapi;
#endif

Authmethod *authmethods[] = {
	&method_none,
#ifdef GSSAPI
	&method_external,
	&method_gssapi,
#endif
	&method_pubkey,
#ifdef GSSAPI
	&method_gssapi,
#endif
	&method_passwd,
	&method_kbdint,
	&method_hostbased,
	NULL
};

/* protocol */

static void input_service_request(int, u_int32_t, void *);
static void input_userauth_request(int, u_int32_t, void *);

/* helper */
static Authmethod *authmethod_lookup(const char *);
static char *authmethods_get(void);
int user_key_allowed(struct passwd *, Key *);
int hostbased_key_allowed(struct passwd *, const char *, char *, Key *);

/*
 * loop until authctxt->success == TRUE
 */

Authctxt *
do_authentication2(void)
{
	Authctxt *authctxt = authctxt_new();

	x_authctxt = authctxt;		/*XXX*/

	/* challenge-response is implemented via keyboard interactive */
	if (options.challenge_response_authentication)
		options.kbd_interactive_authentication = 1;

	dispatch_init(&dispatch_protocol_error);
	dispatch_set(SSH2_MSG_SERVICE_REQUEST, &input_service_request);
	dispatch_run(DISPATCH_BLOCK, &authctxt->success, authctxt);

	return (authctxt);
}

static void
input_service_request(int type, u_int32_t seq, void *ctxt)
{
	Authctxt *authctxt = ctxt;
	u_int len;
	int acceptit = 0;
	char *service = packet_get_string(&len);
	packet_check_eom();

	if (authctxt == NULL)
		fatal("input_service_request: no authctxt");

	if (strcmp(service, "ssh-userauth") == 0) {
		if (!authctxt->success) {
			acceptit = 1;
			/* now we can handle user-auth requests */
			dispatch_set(SSH2_MSG_USERAUTH_REQUEST, &input_userauth_request);
		}
	}
	/* XXX all other service requests are denied */

	if (acceptit) {
		packet_start(SSH2_MSG_SERVICE_ACCEPT);
		packet_put_cstring(service);
		packet_send();
		packet_write_wait();
	} else {
		debug("bad service request %s", service);
		packet_disconnect("bad service request %s", service);
	}
	xfree(service);
}

static void
input_userauth_request(int type, u_int32_t seq, void *ctxt)
{
	Authctxt *authctxt = ctxt;
	Authmethod *m = NULL;
	char *user, *service, *method, *style = NULL;
	int authenticated = 0;

	if (authctxt == NULL)
		fatal("input_userauth_request: no authctxt");

	user = packet_get_string(NULL);
	service = packet_get_string(NULL);
	method = packet_get_string(NULL);

#ifdef GSSAPI
	if (strcmp(user, "") == 0) {
	    debug("received empty username for %s", method);
	    if (strcmp(method, "external-keyx") == 0) {
		char *lname = NULL;
		PRIVSEP(ssh_gssapi_localname(&lname));
		if (lname && lname[0] != '\0') {
		    xfree(user);
		    user = lname;
		    debug("set username to %s from gssapi context", user);
		} else if (authctxt->valid) {
		    debug("failed to set username from gssapi context");
		}
	    }
	}
#endif

	debug("userauth-request for user %s service %s method %s",
	      (user && user[0]) ? user : "<implicit>", service, method);
	debug("attempt %d failures %d", authctxt->attempt, authctxt->failures);

	if ((style = strchr(user, ':')) != NULL)
		*style++ = 0;

	authctxt->attempt++;
	if (!authctxt->user ||
	    strcmp(user, authctxt->user) != 0) {
		/* setup auth context */
		if (authctxt->user) {
		    xfree(authctxt->user);
		    authctxt->user = NULL;
		}
		if (authctxt->service) {
		    xfree(authctxt->service);
		    authctxt->service = NULL;
		}
		if (authctxt->style) {
		    xfree(authctxt->style);
		    authctxt->style = NULL;
		}
#ifdef GSSAPI
		/* We'll verify the username after we set it from the
		   GSSAPI context. */
		if ((strcmp(user, "") == 0) &&
		    ((strcmp(method, "gssapi") == 0) ||
		     (strcmp(method, "external-keyx") == 0))) {
		    authctxt->pw = NULL;
		    authctxt->valid = 1;
		} else {
#endif
		authctxt->pw = PRIVSEP(getpwnamallow(user));
		if (authctxt->pw && strcmp(service, "ssh-connection")==0) {
			authctxt->valid = 1;
			debug2("input_userauth_request: setting up authctxt for %s", user);
#ifdef USE_PAM
			if (options.use_pam)
				PRIVSEP(start_pam(authctxt->pw->pw_name));
#endif
		} else {
			logit("input_userauth_request: illegal user %s", user);
			authctxt->pw = fakepw();
#ifdef USE_PAM
			if (options.use_pam)
				PRIVSEP(start_pam(user));
#endif
		}
#ifdef GSSAPI
		}
#endif
		setproctitle("%s%s", authctxt->pw ? user : "unknown",
		    use_privsep ? " [net]" : "");
		authctxt->user = xstrdup(user);
		authctxt->service = xstrdup(service);
		authctxt->style = style ? xstrdup(style) : NULL;
		if (use_privsep && (authctxt->attempt == 1))
			mm_inform_authserv(service, style);
	} else if (strcmp(service, authctxt->service) != 0) {
		packet_disconnect("Change of service not allowed: "
		    "(%s,%s) -> (%s,%s)",
		    authctxt->user, authctxt->service, user, service);
	}
	/* reset state */
	auth2_challenge_stop(authctxt);

#ifdef GSSAPI
	dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_TOKEN, NULL);
	dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_EXCHANGE_COMPLETE, NULL);
#endif

	authctxt->postponed = 0;

	/* try to authenticate user */
	m = authmethod_lookup(method);
	if (m != NULL) {
		debug2("input_userauth_request: try method %s", method);
		authenticated =	m->userauth(authctxt);
	}
	userauth_finish(authctxt, authenticated, method);

	xfree(service);
	xfree(user);
	xfree(method);
}

void
userauth_finish(Authctxt *authctxt, int authenticated, char *method)
{
	char *methods;

	if (!authctxt->valid && authenticated)
		fatal("INTERNAL ERROR: authenticated invalid user %s",
		    authctxt->user);

	/* Special handling for root */
	if (authenticated && authctxt->pw->pw_uid == 0 &&
	    !auth_root_allowed(method))
		authenticated = 0;

#ifdef USE_PAM
	if (options.use_pam && authenticated && !PRIVSEP(do_pam_account()))
		authenticated = 0;
#endif

#ifdef _UNICOS
	if (authenticated && cray_access_denied(authctxt->user)) {
		authenticated = 0;
		fatal("Access denied for user %s.",authctxt->user);
	}
#endif /* _UNICOS */

	/* Log before sending the reply */
	auth_log(authctxt, authenticated, method, " ssh2");

	if (authctxt->postponed)
		return;

	/* XXX todo: check if multiple auth methods are needed */
	if (authenticated == 1) {
		/* turn off userauth */
		dispatch_set(SSH2_MSG_USERAUTH_REQUEST, &dispatch_protocol_ignore);
		packet_start(SSH2_MSG_USERAUTH_SUCCESS);
		packet_send();
		packet_write_wait();
		/* now we can break out */
		authctxt->success = 1;
	} else {
		if (authctxt->failures++ > AUTH_FAIL_MAX)
			packet_disconnect(AUTH_FAIL_MSG, authctxt->user);
		methods = authmethods_get();
		packet_start(SSH2_MSG_USERAUTH_FAILURE);
		packet_put_cstring(methods);
		packet_put_char(0);	/* XXX partial success, unused */
		packet_send();
		packet_write_wait();
		xfree(methods);
	}
}

/* get current user */

struct passwd*
auth_get_user(void)
{
	return (x_authctxt != NULL && x_authctxt->valid) ? x_authctxt->pw : NULL;
}

#define	DELIM	","

static char *
authmethods_get(void)
{
	Buffer b;
	char *list;
	int i;

	buffer_init(&b);
	for (i = 0; authmethods[i] != NULL; i++) {
		if (strcmp(authmethods[i]->name, "none") == 0)
			continue;
		if (authmethods[i]->enabled != NULL &&
		    *(authmethods[i]->enabled) != 0) {
			if (buffer_len(&b) > 0)
				buffer_append(&b, ",", 1);
			buffer_append(&b, authmethods[i]->name,
			    strlen(authmethods[i]->name));
		}
	}
	buffer_append(&b, "\0", 1);
	list = xstrdup(buffer_ptr(&b));
	buffer_free(&b);
	return list;
}

static Authmethod *
authmethod_lookup(const char *name)
{
	int i;

	if (name != NULL)
		for (i = 0; authmethods[i] != NULL; i++)
			if (authmethods[i]->enabled != NULL &&
			    *(authmethods[i]->enabled) != 0 &&
			    strcmp(name, authmethods[i]->name) == 0)
				return authmethods[i];
	debug2("Unrecognized authentication method name: %s",
	    name ? name : "NULL");
	return NULL;
}
Commit	Line	Data
3c0ef626	1	/*
	2	* Copyright (c) 2000 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"
70791e56	26	RCSID("$OpenBSD: auth2.c,v 1.102 2003/08/26 09:58:43 markus Exp $");
3c0ef626	27
	28	#include "ssh2.h"
	29	#include "xmalloc.h"
3c0ef626	30	#include "packet.h"
3c0ef626	31	#include "log.h"
3c0ef626	32	#include "servconf.h"
3c0ef626	33	#include "auth.h"
3c0ef626	34	#include "dispatch.h"
3c0ef626	35	#include "pathnames.h"
2980ea68	36	#include "monitor_wrap.h"
3c0ef626	37
5598e598	38	#ifdef GSSAPI
	39	#include "ssh-gss.h"
	40	#endif
	41
3c0ef626	42	/* import */
	43	extern ServerOptions options;
	44	extern u_char *session_id2;
70791e56	45	extern u_int session_id2_len;
3c0ef626	46
2980ea68	47	Authctxt *x_authctxt = NULL;
3c0ef626	48
ff2d7a98	49	/* methods */
	50
	51	extern Authmethod method_none;
ff2d7a98	52	extern Authmethod method_pubkey;
	53	extern Authmethod method_passwd;
	54	extern Authmethod method_kbdint;
	55	extern Authmethod method_hostbased;
88928908	56	#ifdef GSSAPI
	57	extern Authmethod method_external;
	58	extern Authmethod method_gssapi;
	59	#endif
ff2d7a98	60
	61	Authmethod *authmethods[] = {
	62	&method_none,
	63	#ifdef GSSAPI
	64	&method_external,
	65	&method_gssapi,
	66	#endif
	67	&method_pubkey,
70791e56	68	#ifdef GSSAPI
	69	&method_gssapi,
	70	#endif
ff2d7a98	71	&method_passwd,
	72	&method_kbdint,
	73	&method_hostbased,
	74	NULL
3c0ef626	75	};
	76
	77	/* protocol */
	78
1e608e42	79	static void input_service_request(int, u_int32_t, void *);
1e608e42	80	static void input_userauth_request(int, u_int32_t, void *);
3c0ef626	81
	82	/* helper */
	83	static Authmethod authmethod_lookup(const char );
	84	static char *authmethods_get(void);
2980ea68	85	int user_key_allowed(struct passwd , Key );
2980ea68	86	int hostbased_key_allowed(struct passwd , const char , char , Key );
3c0ef626	87
3c0ef626	88	/*
	89	* loop until authctxt->success == TRUE
	90	*/
	91
2980ea68	92	Authctxt *
1e608e42	93	do_authentication2(void)
3c0ef626	94	{
	95	Authctxt *authctxt = authctxt_new();
	96
	97	x_authctxt = authctxt; /XXX/
	98
	99	/* challenge-response is implemented via keyboard interactive */
	100	if (options.challenge_response_authentication)
	101	options.kbd_interactive_authentication = 1;
3c0ef626	102
1e608e42	103	dispatch_init(&dispatch_protocol_error);
3c0ef626	104	dispatch_set(SSH2_MSG_SERVICE_REQUEST, &input_service_request);
3c0ef626	105	dispatch_run(DISPATCH_BLOCK, &authctxt->success, authctxt);
2980ea68	106
2980ea68	107	return (authctxt);
3c0ef626	108	}
	109
	110	static void
1e608e42	111	input_service_request(int type, u_int32_t seq, void *ctxt)
3c0ef626	112	{
	113	Authctxt *authctxt = ctxt;
	114	u_int len;
e54b3d7c	115	int acceptit = 0;
3c0ef626	116	char *service = packet_get_string(&len);
1e608e42	117	packet_check_eom();
3c0ef626	118
	119	if (authctxt == NULL)
	120	fatal("input_service_request: no authctxt");
	121
	122	if (strcmp(service, "ssh-userauth") == 0) {
	123	if (!authctxt->success) {
e54b3d7c	124	acceptit = 1;
3c0ef626	125	/* now we can handle user-auth requests */
	126	dispatch_set(SSH2_MSG_USERAUTH_REQUEST, &input_userauth_request);
	127	}
	128	}
	129	/* XXX all other service requests are denied */
	130
e54b3d7c	131	if (acceptit) {
3c0ef626	132	packet_start(SSH2_MSG_SERVICE_ACCEPT);
	133	packet_put_cstring(service);
	134	packet_send();
	135	packet_write_wait();
	136	} else {
	137	debug("bad service request %s", service);
	138	packet_disconnect("bad service request %s", service);
	139	}
	140	xfree(service);
	141	}
	142
	143	static void
1e608e42	144	input_userauth_request(int type, u_int32_t seq, void *ctxt)
3c0ef626	145	{
	146	Authctxt *authctxt = ctxt;
	147	Authmethod *m = NULL;
	148	char user, service, method, style = NULL;
	149	int authenticated = 0;
	150
	151	if (authctxt == NULL)
	152	fatal("input_userauth_request: no authctxt");
	153
	154	user = packet_get_string(NULL);
	155	service = packet_get_string(NULL);
	156	method = packet_get_string(NULL);
2980ea68	157
2980ea68	158	#ifdef GSSAPI
ff2d7a98	159	if (strcmp(user, "") == 0) {
c2397a66	160	debug("received empty username for %s", method);
	161	if (strcmp(method, "external-keyx") == 0) {
	162	char *lname = NULL;
	163	PRIVSEP(ssh_gssapi_localname(&lname));
	164	if (lname && lname[0] != '\0') {
	165	xfree(user);
	166	user = lname;
	167	debug("set username to %s from gssapi context", user);
	168	} else if (authctxt->valid) {
	169	debug("failed to set username from gssapi context");
	170	}
ff2d7a98	171	}
	172	}
	173	#endif
2980ea68	174
c2397a66	175	debug("userauth-request for user %s service %s method %s",
c2397a66	176	(user && user[0]) ? user : "<implicit>", service, method);
3c0ef626	177	debug("attempt %d failures %d", authctxt->attempt, authctxt->failures);
	178
	179	if ((style = strchr(user, ':')) != NULL)
	180	*style++ = 0;
	181
c2397a66	182	authctxt->attempt++;
ff2d7a98	183	if (!authctxt->user \|\|
ff2d7a98	184	strcmp(user, authctxt->user) != 0) {
3c0ef626	185	/* setup auth context */
ff2d7a98	186	if (authctxt->user) {
	187	xfree(authctxt->user);
	188	authctxt->user = NULL;
	189	}
	190	if (authctxt->service) {
	191	xfree(authctxt->service);
	192	authctxt->service = NULL;
	193	}
	194	if (authctxt->style) {
	195	xfree(authctxt->style);
	196	authctxt->style = NULL;
	197	}
c2397a66	198	#ifdef GSSAPI
	199	/* We'll verify the username after we set it from the
	200	GSSAPI context. */
	201	if ((strcmp(user, "") == 0) &&
	202	((strcmp(method, "gssapi") == 0) \|\|
	203	(strcmp(method, "external-keyx") == 0))) {
	204	authctxt->pw = NULL;
	205	authctxt->valid = 1;
	206	} else {
	207	#endif
2980ea68	208	authctxt->pw = PRIVSEP(getpwnamallow(user));
2980ea68	209	if (authctxt->pw && strcmp(service, "ssh-connection")==0) {
3c0ef626	210	authctxt->valid = 1;
	211	debug2("input_userauth_request: setting up authctxt for %s", user);
	212	#ifdef USE_PAM
70791e56	213	if (options.use_pam)
70791e56	214	PRIVSEP(start_pam(authctxt->pw->pw_name));
3c0ef626	215	#endif
3c0ef626	216	} else {
70791e56	217	logit("input_userauth_request: illegal user %s", user);
70791e56	218	authctxt->pw = fakepw();
3c0ef626	219	#ifdef USE_PAM
70791e56	220	if (options.use_pam)
70791e56	221	PRIVSEP(start_pam(user));
3c0ef626	222	#endif
3c0ef626	223	}
c2397a66	224	#ifdef GSSAPI
	225	}
	226	#endif
2980ea68	227	setproctitle("%s%s", authctxt->pw ? user : "unknown",
2980ea68	228	use_privsep ? " [net]" : "");
3c0ef626	229	authctxt->user = xstrdup(user);
	230	authctxt->service = xstrdup(service);
	231	authctxt->style = style ? xstrdup(style) : NULL;
c2397a66	232	if (use_privsep && (authctxt->attempt == 1))
2980ea68	233	mm_inform_authserv(service, style);
88928908	234	} else if (strcmp(service, authctxt->service) != 0) {
	235	packet_disconnect("Change of service not allowed: "
	236	"(%s,%s) -> (%s,%s)",
	237	authctxt->user, authctxt->service, user, service);
3c0ef626	238	}
3c0ef626	239	/* reset state */
1e608e42	240	auth2_challenge_stop(authctxt);
5598e598	241
5598e598	242	#ifdef GSSAPI
1e608e42	243	dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_TOKEN, NULL);
1e608e42	244	dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_EXCHANGE_COMPLETE, NULL);
5598e598	245	#endif
5598e598	246
3c0ef626	247	authctxt->postponed = 0;
3c0ef626	248
	249	/* try to authenticate user */
	250	m = authmethod_lookup(method);
	251	if (m != NULL) {
	252	debug2("input_userauth_request: try method %s", method);
	253	authenticated = m->userauth(authctxt);
	254	}
	255	userauth_finish(authctxt, authenticated, method);
	256
	257	xfree(service);
	258	xfree(user);
	259	xfree(method);
	260	}
	261
	262	void
	263	userauth_finish(Authctxt authctxt, int authenticated, char method)
	264	{
	265	char *methods;
	266
	267	if (!authctxt->valid && authenticated)
	268	fatal("INTERNAL ERROR: authenticated invalid user %s",
	269	authctxt->user);
	270
	271	/* Special handling for root */
1c14df9e	272	if (authenticated && authctxt->pw->pw_uid == 0 &&
3c0ef626	273	!auth_root_allowed(method))
	274	authenticated = 0;
	275
	276	#ifdef USE_PAM
70791e56	277	if (options.use_pam && authenticated && !PRIVSEP(do_pam_account()))
3c0ef626	278	authenticated = 0;
70791e56	279	#endif
3c0ef626	280
e54b3d7c	281	#ifdef _UNICOS
	282	if (authenticated && cray_access_denied(authctxt->user)) {
	283	authenticated = 0;
	284	fatal("Access denied for user %s.",authctxt->user);
	285	}
	286	#endif /* _UNICOS */
	287
3c0ef626	288	/* Log before sending the reply */
	289	auth_log(authctxt, authenticated, method, " ssh2");
	290
	291	if (authctxt->postponed)
	292	return;
	293
	294	/* XXX todo: check if multiple auth methods are needed */
	295	if (authenticated == 1) {
	296	/* turn off userauth */
1e608e42	297	dispatch_set(SSH2_MSG_USERAUTH_REQUEST, &dispatch_protocol_ignore);
3c0ef626	298	packet_start(SSH2_MSG_USERAUTH_SUCCESS);
	299	packet_send();
	300	packet_write_wait();
	301	/* now we can break out */
	302	authctxt->success = 1;
	303	} else {
70791e56	304	if (authctxt->failures++ > AUTH_FAIL_MAX)
3c0ef626	305	packet_disconnect(AUTH_FAIL_MSG, authctxt->user);
3c0ef626	306	methods = authmethods_get();
	307	packet_start(SSH2_MSG_USERAUTH_FAILURE);
	308	packet_put_cstring(methods);
	309	packet_put_char(0); /* XXX partial success, unused */
	310	packet_send();
	311	packet_write_wait();
	312	xfree(methods);
	313	}
	314	}
	315
3c0ef626	316	/* get current user */
	317
	318	struct passwd*
	319	auth_get_user(void)
	320	{
	321	return (x_authctxt != NULL && x_authctxt->valid) ? x_authctxt->pw : NULL;
	322	}
	323
	324	#define DELIM ","
	325
	326	static char *
	327	authmethods_get(void)
	328	{
1e608e42	329	Buffer b;
3c0ef626	330	char *list;
ff2d7a98	331	int i;
3c0ef626	332
1e608e42	333	buffer_init(&b);
ff2d7a98	334	for (i = 0; authmethods[i] != NULL; i++) {
ff2d7a98	335	if (strcmp(authmethods[i]->name, "none") == 0)
3c0ef626	336	continue;
ff2d7a98	337	if (authmethods[i]->enabled != NULL &&
ff2d7a98	338	*(authmethods[i]->enabled) != 0) {
1e608e42	339	if (buffer_len(&b) > 0)
1e608e42	340	buffer_append(&b, ",", 1);
ff2d7a98	341	buffer_append(&b, authmethods[i]->name,
ff2d7a98	342	strlen(authmethods[i]->name));
3c0ef626	343	}
3c0ef626	344	}
1e608e42	345	buffer_append(&b, "\0", 1);
	346	list = xstrdup(buffer_ptr(&b));
	347	buffer_free(&b);
3c0ef626	348	return list;
	349	}
	350
	351	static Authmethod *
	352	authmethod_lookup(const char *name)
	353	{
ff2d7a98	354	int i;
ff2d7a98	355
3c0ef626	356	if (name != NULL)
ff2d7a98	357	for (i = 0; authmethods[i] != NULL; i++)
	358	if (authmethods[i]->enabled != NULL &&
	359	*(authmethods[i]->enabled) != 0 &&
	360	strcmp(name, authmethods[i]->name) == 0)
	361	return authmethods[i];
	362	debug2("Unrecognized authentication method name: %s",
	363	name ? name : "NULL");
3c0ef626	364	return NULL;
3c0ef626	365	}