[openssh.git] / auth2.c

/* $OpenBSD: auth2.c,v 1.121 2009/06/22 05:39:28 dtucker Exp $ */
/*
 * 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"

#include <sys/types.h>
#include <sys/stat.h>
#include <sys/uio.h>

#include <fcntl.h>
#include <pwd.h>
#include <stdarg.h>
#include <string.h>
#include <unistd.h>

#include "atomicio.h"
#include "xmalloc.h"
#include "ssh2.h"
#include "packet.h"
#include "log.h"
#include "buffer.h"
#include "servconf.h"
#include "compat.h"
#include "key.h"
#include "hostfile.h"
#include "auth.h"
#include "dispatch.h"
#include "pathnames.h"
#include "buffer.h"

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

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

/* 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_gssapi;
#endif
#ifdef JPAKE
extern Authmethod method_jpake;
#endif

Authmethod *authmethods[] = {
	&method_none,
	&method_pubkey,
#ifdef GSSAPI
	&method_gssapi,
#endif
#ifdef JPAKE
	&method_jpake,
#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);

char *
auth2_read_banner(void)
{
	struct stat st;
	char *banner = NULL;
	size_t len, n;
	int fd;

	if ((fd = open(options.banner, O_RDONLY)) == -1)
		return (NULL);
	if (fstat(fd, &st) == -1) {
		close(fd);
		return (NULL);
	}
	if (st.st_size > 1*1024*1024) {
		close(fd);
		return (NULL);
	}

	len = (size_t)st.st_size;		/* truncate */
	banner = xmalloc(len + 1);
	n = atomicio(read, fd, banner, len);
	close(fd);

	if (n != len) {
		xfree(banner);
		return (NULL);
	}
	banner[n] = '\0';

	return (banner);
}

void
userauth_send_banner(const char *msg)
{
	if (datafellows & SSH_BUG_BANNER)
		return;

	packet_start(SSH2_MSG_USERAUTH_BANNER);
	packet_put_cstring(msg);
	packet_put_cstring("");		/* language, unused */
	packet_send();
	debug("%s: sent", __func__);
}

static void
userauth_banner(void)
{
	char *banner = NULL;

	if (options.banner == NULL ||
	    strcasecmp(options.banner, "none") == 0 ||
	    (datafellows & SSH_BUG_BANNER) != 0)
		return;

	if ((banner = PRIVSEP(auth2_read_banner())) == NULL)
		goto done;
	userauth_send_banner(banner);

done:
	if (banner)
		xfree(banner);
}

/*
 * loop until authctxt->success == TRUE
 */
void
do_authentication2(Authctxt *authctxt)
{
	dispatch_init(&dispatch_protocol_error);
	dispatch_set(SSH2_MSG_SERVICE_REQUEST, &input_service_request);
	dispatch_run(DISPATCH_BLOCK, &authctxt->success, authctxt);
}

/*ARGSUSED*/
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);
}

/*ARGSUSED*/
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);
	debug("userauth-request for user %s service %s method %s", user, service, method);
	debug("attempt %d failures %d", authctxt->attempt, authctxt->failures);

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

	if (authctxt->attempt++ == 0) {
		/* setup auth context */
		authctxt->pw = PRIVSEP(getpwnamallow(user));
		authctxt->user = xstrdup(user);
		if (authctxt->pw && strcmp(service, "ssh-connection")==0) {
			authctxt->valid = 1;
			debug2("input_userauth_request: setting up authctxt for %s", user);
		} else {
			logit("input_userauth_request: invalid user %s", user);
			authctxt->pw = fakepw();
#ifdef SSH_AUDIT_EVENTS
			PRIVSEP(audit_event(SSH_INVALID_USER));
#endif
		}
#ifdef USE_PAM
		if (options.use_pam)
			PRIVSEP(start_pam(authctxt));
#endif
		setproctitle("%s%s", authctxt->valid ? user : "unknown",
		    use_privsep ? " [net]" : "");
		authctxt->service = xstrdup(service);
		authctxt->style = style ? xstrdup(style) : NULL;
		if (use_privsep)
			mm_inform_authserv(service, style);
		userauth_banner();
	} else if (strcmp(user, authctxt->user) != 0 ||
	    strcmp(service, authctxt->service) != 0) {
		packet_disconnect("Change of username or service not allowed: "
		    "(%s,%s) -> (%s,%s)",
		    authctxt->user, authctxt->service, user, service);
	}
	/* reset state */
	auth2_challenge_stop(authctxt);
#ifdef JPAKE
	auth2_jpake_stop(authctxt);
#endif

#ifdef GSSAPI
	/* XXX move to auth2_gssapi_stop() */
	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 && authctxt->failures < options.max_authtries) {
		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 SSH_AUDIT_EVENTS
		PRIVSEP(audit_event(SSH_LOGIN_ROOT_DENIED));
#endif
	}

#ifdef USE_PAM
	if (options.use_pam && authenticated) {
		if (!PRIVSEP(do_pam_account())) {
			/* if PAM returned a message, send it to the user */
			if (buffer_len(&loginmsg) > 0) {
				buffer_append(&loginmsg, "\0", 1);
				userauth_send_banner(buffer_ptr(&loginmsg));
				packet_write_wait();
			}
			fatal("Access denied for user %s by PAM account "
			    "configuration", authctxt->user);
		}
	}
#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 {

		/* Allow initial try of "none" auth without failure penalty */
		if (authctxt->attempt > 1 || strcmp(method, "none") != 0)
			authctxt->failures++;
		if (authctxt->failures >= options.max_authtries) {
#ifdef SSH_AUDIT_EVENTS
			PRIVSEP(audit_event(SSH_LOGIN_EXCEED_MAXTRIES));
#endif
			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);
	}
}

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
127c96db	1	/* $OpenBSD: auth2.c,v 1.121 2009/06/22 05:39:28 dtucker Exp $ */
a306f2dd	2	/*
	3	* Copyright (c) 2000 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.
a306f2dd	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	*/
bcbf86ec	25
a306f2dd	26	#include "includes.h"
a306f2dd	27
b1842393	28	#include <sys/types.h>
221fc73c	29	#include <sys/stat.h>
221fc73c	30	#include <sys/uio.h>
b1842393	31
221fc73c	32	#include <fcntl.h>
b1842393	33	#include <pwd.h>
31652869	34	#include <stdarg.h>
00146caa	35	#include <string.h>
221fc73c	36	#include <unistd.h>
b1842393	37
71709bcd	38	#include "atomicio.h"
9b9302ea	39	#include "xmalloc.h"
31652869	40	#include "ssh2.h"
a306f2dd	41	#include "packet.h"
42f11eb2	42	#include "log.h"
31652869	43	#include "buffer.h"
a306f2dd	44	#include "servconf.h"
a306f2dd	45	#include "compat.h"
31652869	46	#include "key.h"
31652869	47	#include "hostfile.h"
a306f2dd	48	#include "auth.h"
a306f2dd	49	#include "dispatch.h"
42f11eb2	50	#include "pathnames.h"
ba6dd90e	51	#include "buffer.h"
a306f2dd	52
7364bd04	53	#ifdef GSSAPI
	54	#include "ssh-gss.h"
	55	#endif
31652869	56	#include "monitor_wrap.h"
7364bd04	57
a306f2dd	58	/* import */
a306f2dd	59	extern ServerOptions options;
1e3b8b07	60	extern u_char *session_id2;
a27002e5	61	extern u_int session_id2_len;
ba6dd90e	62	extern Buffer loginmsg;
a306f2dd	63
01c24737	64	/* methods */
	65
	66	extern Authmethod method_none;
	67	extern Authmethod method_pubkey;
	68	extern Authmethod method_passwd;
	69	extern Authmethod method_kbdint;
	70	extern Authmethod method_hostbased;
7364bd04	71	#ifdef GSSAPI
	72	extern Authmethod method_gssapi;
	73	#endif
5adf6b9a	74	#ifdef JPAKE
	75	extern Authmethod method_jpake;
	76	#endif
01c24737	77
	78	Authmethod *authmethods[] = {
	79	&method_none,
	80	&method_pubkey,
7364bd04	81	#ifdef GSSAPI
7364bd04	82	&method_gssapi,
5adf6b9a	83	#endif
	84	#ifdef JPAKE
	85	&method_jpake,
7364bd04	86	#endif
01c24737	87	&method_passwd,
	88	&method_kbdint,
	89	&method_hostbased,
	90	NULL
94ec8c6b	91	};
94ec8c6b	92
a306f2dd	93	/* protocol */
a306f2dd	94
7819b5c3	95	static void input_service_request(int, u_int32_t, void *);
7819b5c3	96	static void input_userauth_request(int, u_int32_t, void *);
a306f2dd	97
a306f2dd	98	/* helper */
396c147e	99	static Authmethod authmethod_lookup(const char );
ffb215be	100	static char *authmethods_get(void);
a306f2dd	101
221fc73c	102	char *
	103	auth2_read_banner(void)
	104	{
	105	struct stat st;
	106	char *banner = NULL;
	107	size_t len, n;
	108	int fd;
	109
	110	if ((fd = open(options.banner, O_RDONLY)) == -1)
	111	return (NULL);
	112	if (fstat(fd, &st) == -1) {
	113	close(fd);
	114	return (NULL);
	115	}
	116	if (st.st_size > 110241024) {
	117	close(fd);
	118	return (NULL);
	119	}
	120
	121	len = (size_t)st.st_size; /* truncate */
	122	banner = xmalloc(len + 1);
	123	n = atomicio(read, fd, banner, len);
	124	close(fd);
	125
	126	if (n != len) {
	127	xfree(banner);
	128	return (NULL);
	129	}
	130	banner[n] = '\0';
	131
	132	return (banner);
	133	}
	134
	135	void
	136	userauth_send_banner(const char *msg)
	137	{
	138	if (datafellows & SSH_BUG_BANNER)
	139	return;
	140
	141	packet_start(SSH2_MSG_USERAUTH_BANNER);
	142	packet_put_cstring(msg);
	143	packet_put_cstring(""); /* language, unused */
	144	packet_send();
	145	debug("%s: sent", __func__);
	146	}
	147
	148	static void
	149	userauth_banner(void)
	150	{
	151	char *banner = NULL;
	152
	153	if (options.banner == NULL \|\|
	154	strcasecmp(options.banner, "none") == 0 \|\|
	155	(datafellows & SSH_BUG_BANNER) != 0)
	156	return;
	157
	158	if ((banner = PRIVSEP(auth2_read_banner())) == NULL)
	159	goto done;
	160	userauth_send_banner(banner);
	161
	162	done:
	163	if (banner)
	164	xfree(banner);
	165	}
166
a306f2dd	167	/*
94ec8c6b	168	* loop until authctxt->success == TRUE
a306f2dd	169	*/
2362db19	170	void
2362db19	171	do_authentication2(Authctxt *authctxt)
a306f2dd	172	{
6367063f	173	dispatch_init(&dispatch_protocol_error);
a306f2dd	174	dispatch_set(SSH2_MSG_SERVICE_REQUEST, &input_service_request);
94ec8c6b	175	dispatch_run(DISPATCH_BLOCK, &authctxt->success, authctxt);
a306f2dd	176	}
a306f2dd	177
fe8c3af1	178	/ARGSUSED/
396c147e	179	static void
7819b5c3	180	input_service_request(int type, u_int32_t seq, void *ctxt)
a306f2dd	181	{
94ec8c6b	182	Authctxt *authctxt = ctxt;
1e3b8b07	183	u_int len;
7fdc56c5	184	int acceptit = 0;
a306f2dd	185	char *service = packet_get_string(&len);
95500969	186	packet_check_eom();
a306f2dd	187
94ec8c6b	188	if (authctxt == NULL)
	189	fatal("input_service_request: no authctxt");
	190
a306f2dd	191	if (strcmp(service, "ssh-userauth") == 0) {
94ec8c6b	192	if (!authctxt->success) {
7fdc56c5	193	acceptit = 1;
a306f2dd	194	/* now we can handle user-auth requests */
	195	dispatch_set(SSH2_MSG_USERAUTH_REQUEST, &input_userauth_request);
	196	}
	197	}
	198	/* XXX all other service requests are denied */
	199
7fdc56c5	200	if (acceptit) {
a306f2dd	201	packet_start(SSH2_MSG_SERVICE_ACCEPT);
	202	packet_put_cstring(service);
	203	packet_send();
	204	packet_write_wait();
	205	} else {
	206	debug("bad service request %s", service);
	207	packet_disconnect("bad service request %s", service);
	208	}
	209	xfree(service);
	210	}
	211
fe8c3af1	212	/ARGSUSED/
396c147e	213	static void
7819b5c3	214	input_userauth_request(int type, u_int32_t seq, void *ctxt)
a306f2dd	215	{
94ec8c6b	216	Authctxt *authctxt = ctxt;
94ec8c6b	217	Authmethod *m = NULL;
59c97189	218	char user, service, method, style = NULL;
a306f2dd	219	int authenticated = 0;
a306f2dd	220
94ec8c6b	221	if (authctxt == NULL)
94ec8c6b	222	fatal("input_userauth_request: no authctxt");
a306f2dd	223
94ec8c6b	224	user = packet_get_string(NULL);
	225	service = packet_get_string(NULL);
	226	method = packet_get_string(NULL);
	227	debug("userauth-request for user %s service %s method %s", user, service, method);
8abcdba4	228	debug("attempt %d failures %d", authctxt->attempt, authctxt->failures);
94ec8c6b	229
59c97189	230	if ((style = strchr(user, ':')) != NULL)
	231	*style++ = 0;
	232
2b87da3b	233	if (authctxt->attempt++ == 0) {
63284fbb	234	/* setup auth context */
f7ed12f1	235	authctxt->pw = PRIVSEP(getpwnamallow(user));
529d73ab	236	authctxt->user = xstrdup(user);
f7ed12f1	237	if (authctxt->pw && strcmp(service, "ssh-connection")==0) {
94ec8c6b	238	authctxt->valid = 1;
94ec8c6b	239	debug2("input_userauth_request: setting up authctxt for %s", user);
94ec8c6b	240	} else {
d77347cc	241	logit("input_userauth_request: invalid user %s", user);
96d0bf74	242	authctxt->pw = fakepw();
6039eeef	243	#ifdef SSH_AUDIT_EVENTS
6039eeef	244	PRIVSEP(audit_event(SSH_INVALID_USER));
04fc7a67	245	#endif
94ec8c6b	246	}
b6c37221	247	#ifdef USE_PAM
	248	if (options.use_pam)
	249	PRIVSEP(start_pam(authctxt));
	250	#endif
bd5c0694	251	setproctitle("%s%s", authctxt->valid ? user : "unknown",
1853d1ef	252	use_privsep ? " [net]" : "");
94ec8c6b	253	authctxt->service = xstrdup(service);
2a6a054e	254	authctxt->style = style ? xstrdup(style) : NULL;
1853d1ef	255	if (use_privsep)
1853d1ef	256	mm_inform_authserv(service, style);
221fc73c	257	userauth_banner();
2a6a054e	258	} else if (strcmp(user, authctxt->user) != 0 \|\|
	259	strcmp(service, authctxt->service) != 0) {
	260	packet_disconnect("Change of username or service not allowed: "
	261	"(%s,%s) -> (%s,%s)",
	262	authctxt->user, authctxt->service, user, service);
a306f2dd	263	}
59c97189	264	/* reset state */
2f293d43	265	auth2_challenge_stop(authctxt);
5adf6b9a	266	#ifdef JPAKE
	267	auth2_jpake_stop(authctxt);
	268	#endif
7364bd04	269
7364bd04	270	#ifdef GSSAPI
5adf6b9a	271	/* XXX move to auth2_gssapi_stop() */
7364bd04	272	dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_TOKEN, NULL);
	273	dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_EXCHANGE_COMPLETE, NULL);
	274	#endif
	275
59c97189	276	authctxt->postponed = 0;
9cd45ea4	277
59c97189	278	/* try to authenticate user */
94ec8c6b	279	m = authmethod_lookup(method);
221fc73c	280	if (m != NULL && authctxt->failures < options.max_authtries) {
94ec8c6b	281	debug2("input_userauth_request: try method %s", method);
94ec8c6b	282	authenticated = m->userauth(authctxt);
9cd45ea4	283	}
d9cd3575	284	userauth_finish(authctxt, authenticated, method);
	285
	286	xfree(service);
	287	xfree(user);
	288	xfree(method);
	289	}
	290
	291	void
	292	userauth_finish(Authctxt authctxt, int authenticated, char method)
	293	{
4e81159c	294	char *methods;
4e81159c	295
59c97189	296	if (!authctxt->valid && authenticated)
	297	fatal("INTERNAL ERROR: authenticated invalid user %s",
	298	authctxt->user);
9cd45ea4	299
94ec8c6b	300	/* Special handling for root */
5d47f1d4	301	if (authenticated && authctxt->pw->pw_uid == 0 &&
c00e4d75	302	!auth_root_allowed(method)) {
a306f2dd	303	authenticated = 0;
6039eeef	304	#ifdef SSH_AUDIT_EVENTS
6039eeef	305	PRIVSEP(audit_event(SSH_LOGIN_ROOT_DENIED));
c00e4d75	306	#endif
c00e4d75	307	}
a306f2dd	308
5b9e2464	309	#ifdef USE_PAM
ba6dd90e	310	if (options.use_pam && authenticated) {
ba6dd90e	311	if (!PRIVSEP(do_pam_account())) {
ba6dd90e	312	/* if PAM returned a message, send it to the user */
	313	if (buffer_len(&loginmsg) > 0) {
	314	buffer_append(&loginmsg, "\0", 1);
	315	userauth_send_banner(buffer_ptr(&loginmsg));
9aab0af7	316	packet_write_wait();
ba6dd90e	317	}
9aab0af7	318	fatal("Access denied for user %s by PAM account "
98c044d0	319	"configuration", authctxt->user);
ba6dd90e	320	}
ba6dd90e	321	}
5b9e2464	322	#endif
5b9e2464	323
ef51930f	324	#ifdef _UNICOS
	325	if (authenticated && cray_access_denied(authctxt->user)) {
	326	authenticated = 0;
	327	fatal("Access denied for user %s.",authctxt->user);
	328	}
	329	#endif /* _UNICOS */
	330
94ec8c6b	331	/* Log before sending the reply */
59c97189	332	auth_log(authctxt, authenticated, method, " ssh2");
59c97189	333
4e81159c	334	if (authctxt->postponed)
	335	return;
	336
	337	/* XXX todo: check if multiple auth methods are needed */
	338	if (authenticated == 1) {
	339	/* turn off userauth */
6367063f	340	dispatch_set(SSH2_MSG_USERAUTH_REQUEST, &dispatch_protocol_ignore);
4e81159c	341	packet_start(SSH2_MSG_USERAUTH_SUCCESS);
	342	packet_send();
	343	packet_write_wait();
	344	/* now we can break out */
	345	authctxt->success = 1;
	346	} else {
71709bcd	347
	348	/* Allow initial try of "none" auth without failure penalty */
	349	if (authctxt->attempt > 1 \|\| strcmp(method, "none") != 0)
	350	authctxt->failures++;
	351	if (authctxt->failures >= options.max_authtries) {
6039eeef	352	#ifdef SSH_AUDIT_EVENTS
6039eeef	353	PRIVSEP(audit_event(SSH_LOGIN_EXCEED_MAXTRIES));
c00e4d75	354	#endif
4e81159c	355	packet_disconnect(AUTH_FAIL_MSG, authctxt->user);
c00e4d75	356	}
4e81159c	357	methods = authmethods_get();
	358	packet_start(SSH2_MSG_USERAUTH_FAILURE);
	359	packet_put_cstring(methods);
	360	packet_put_char(0); /* XXX partial success, unused */
	361	packet_send();
	362	packet_write_wait();
	363	xfree(methods);
	364	}
94ec8c6b	365	}
94ec8c6b	366
ffb215be	367	static char *
94ec8c6b	368	authmethods_get(void)
a306f2dd	369	{
3469eac4	370	Buffer b;
94ec8c6b	371	char *list;
01c24737	372	int i;
94ec8c6b	373
3469eac4	374	buffer_init(&b);
01c24737	375	for (i = 0; authmethods[i] != NULL; i++) {
01c24737	376	if (strcmp(authmethods[i]->name, "none") == 0)
94ec8c6b	377	continue;
01c24737	378	if (authmethods[i]->enabled != NULL &&
01c24737	379	*(authmethods[i]->enabled) != 0) {
3469eac4	380	if (buffer_len(&b) > 0)
3469eac4	381	buffer_append(&b, ",", 1);
01c24737	382	buffer_append(&b, authmethods[i]->name,
01c24737	383	strlen(authmethods[i]->name));
a306f2dd	384	}
a306f2dd	385	}
3469eac4	386	buffer_append(&b, "\0", 1);
	387	list = xstrdup(buffer_ptr(&b));
	388	buffer_free(&b);
94ec8c6b	389	return list;
	390	}
	391
396c147e	392	static Authmethod *
94ec8c6b	393	authmethod_lookup(const char *name)
94ec8c6b	394	{
01c24737	395	int i;
01c24737	396
94ec8c6b	397	if (name != NULL)
01c24737	398	for (i = 0; authmethods[i] != NULL; i++)
	399	if (authmethods[i]->enabled != NULL &&
	400	*(authmethods[i]->enabled) != 0 &&
	401	strcmp(name, authmethods[i]->name) == 0)
	402	return authmethods[i];
	403	debug2("Unrecognized authentication method name: %s",
	404	name ? name : "NULL");
94ec8c6b	405	return NULL;
a306f2dd	406	}
221fc73c	407