[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 1.107 2004/07/28 09:40:29 markus Exp $");

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

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

/* 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_external;
extern Authmethod method_gsskeyex;
extern Authmethod method_gssapi;
extern Authmethod method_gssapi_compat;
#endif

Authmethod *authmethods[] = {
	&method_none,
	&method_pubkey,
#ifdef GSSAPI
	&method_gsskeyex,
	&method_external,
	&method_gssapi,
	&method_gssapi_compat,
#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 *);

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

void
do_authentication2(Authctxt *authctxt)
{
	/* 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);
}

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 (user[0] == '\0') {
	    debug("received empty username for %s", method);
	    if (strcmp(method, "external-keyx") == 0 ||
		strcmp(method, "gssapi-keyex") == 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 {
		    debug("failed to set username from gssapi context");
		}
	    }
	}
#endif

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

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

	/* If first time or username changed or implicit username,
	   setup/reset authentication context. */
	if ((authctxt->attempt++ == 0) ||
	    (strcmp(user, authctxt->user) != 0) ||
	    (strcmp(user, "") == 0)) {
		if (authctxt->user) {
		    xfree(authctxt->user);
		    authctxt->user = NULL;
		}
		authctxt->valid = 0;
#ifdef GSSAPI
		/* If we're going to set the username based on the
		   GSSAPI context later, then wait until then to
		   verify it. Just put in placeholders for now. */
		if ((strcmp(user, "") == 0) &&
		    ((strcmp(method, "gssapi") == 0) ||
		     (strcmp(method, "gssapi-with-mic") == 0))) {
			authctxt->pw = fakepw();
			authctxt->user = xstrdup(user);
		} else {
#endif
		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);
#ifdef USE_PAM
			if (options.use_pam)
				PRIVSEP(start_pam(authctxt));
#endif
		} else {
			logit("input_userauth_request: invalid user %s", user);
			authctxt->pw = fakepw();
#ifdef USE_PAM
			if (options.use_pam)
				PRIVSEP(start_pam(authctxt));
#endif
#ifdef SSH_AUDIT_EVENTS
			PRIVSEP(audit_event(SSH_INVALID_USER));
#endif
		}
#ifdef GSSAPI
		} /* endif for setting username based on GSSAPI context */
#endif
		setproctitle("%s%s", authctxt->valid ? user : "unknown",
		    use_privsep ? " [net]" : "");
#ifdef GSSAPI
		if (authctxt->attempt == 1) {
#endif
		authctxt->service = xstrdup(service);
		authctxt->style = style ? xstrdup(style) : NULL;
		if (use_privsep)
			mm_inform_authserv(service, style);
#ifdef GSSAPI
		} /* if (authctxt->attempt == 1) */
#endif
	}
	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;
	authctxt->server_caused_failure = 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 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 {
		/* Dont count server configuration issues against the client */
		if (!authctxt->server_caused_failure && 
		    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);
	}
}

#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"
1b56ff3d	26	RCSID("$OpenBSD: auth2.c,v 1.107 2004/07/28 09:40:29 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"
416fd2a8	33	#include "compat.h"
3c0ef626	34	#include "auth.h"
3c0ef626	35	#include "dispatch.h"
3c0ef626	36	#include "pathnames.h"
2980ea68	37	#include "monitor_wrap.h"
34fee935	38	#include "buffer.h"
3c0ef626	39
5598e598	40	#ifdef GSSAPI
	41	#include "ssh-gss.h"
	42	#endif
	43
3c0ef626	44	/* import */
	45	extern ServerOptions options;
	46	extern u_char *session_id2;
70791e56	47	extern u_int session_id2_len;
34fee935	48	extern Buffer loginmsg;
3c0ef626	49
ff2d7a98	50	/* methods */
	51
	52	extern Authmethod method_none;
ff2d7a98	53	extern Authmethod method_pubkey;
	54	extern Authmethod method_passwd;
	55	extern Authmethod method_kbdint;
	56	extern Authmethod method_hostbased;
88928908	57	#ifdef GSSAPI
88928908	58	extern Authmethod method_external;
34fee935	59	extern Authmethod method_gsskeyex;
88928908	60	extern Authmethod method_gssapi;
416fd2a8	61	extern Authmethod method_gssapi_compat;
88928908	62	#endif
ff2d7a98	63
	64	Authmethod *authmethods[] = {
	65	&method_none,
ff2d7a98	66	&method_pubkey,
70791e56	67	#ifdef GSSAPI
34fee935	68	&method_gsskeyex,
416fd2a8	69	&method_external,
70791e56	70	&method_gssapi,
416fd2a8	71	&method_gssapi_compat,
70791e56	72	#endif
ff2d7a98	73	&method_passwd,
	74	&method_kbdint,
	75	&method_hostbased,
	76	NULL
3c0ef626	77	};
	78
	79	/* protocol */
	80
1e608e42	81	static void input_service_request(int, u_int32_t, void *);
1e608e42	82	static void input_userauth_request(int, u_int32_t, void *);
3c0ef626	83
	84	/* helper */
	85	static Authmethod authmethod_lookup(const char );
	86	static char *authmethods_get(void);
2980ea68	87	int user_key_allowed(struct passwd , Key );
3c0ef626	88
3c0ef626	89	/*
	90	* loop until authctxt->success == TRUE
	91	*/
	92
416fd2a8	93	void
416fd2a8	94	do_authentication2(Authctxt *authctxt)
3c0ef626	95	{
3c0ef626	96	/* challenge-response is implemented via keyboard interactive */
	97	if (options.challenge_response_authentication)
	98	options.kbd_interactive_authentication = 1;
3c0ef626	99
1e608e42	100	dispatch_init(&dispatch_protocol_error);
3c0ef626	101	dispatch_set(SSH2_MSG_SERVICE_REQUEST, &input_service_request);
3c0ef626	102	dispatch_run(DISPATCH_BLOCK, &authctxt->success, authctxt);
3c0ef626	103	}
	104
	105	static void
1e608e42	106	input_service_request(int type, u_int32_t seq, void *ctxt)
3c0ef626	107	{
	108	Authctxt *authctxt = ctxt;
	109	u_int len;
e54b3d7c	110	int acceptit = 0;
3c0ef626	111	char *service = packet_get_string(&len);
1e608e42	112	packet_check_eom();
3c0ef626	113
	114	if (authctxt == NULL)
	115	fatal("input_service_request: no authctxt");
	116
	117	if (strcmp(service, "ssh-userauth") == 0) {
	118	if (!authctxt->success) {
e54b3d7c	119	acceptit = 1;
3c0ef626	120	/* now we can handle user-auth requests */
	121	dispatch_set(SSH2_MSG_USERAUTH_REQUEST, &input_userauth_request);
	122	}
	123	}
	124	/* XXX all other service requests are denied */
	125
e54b3d7c	126	if (acceptit) {
3c0ef626	127	packet_start(SSH2_MSG_SERVICE_ACCEPT);
	128	packet_put_cstring(service);
	129	packet_send();
	130	packet_write_wait();
	131	} else {
	132	debug("bad service request %s", service);
	133	packet_disconnect("bad service request %s", service);
	134	}
	135	xfree(service);
	136	}
	137
	138	static void
1e608e42	139	input_userauth_request(int type, u_int32_t seq, void *ctxt)
3c0ef626	140	{
	141	Authctxt *authctxt = ctxt;
	142	Authmethod *m = NULL;
	143	char user, service, method, style = NULL;
	144	int authenticated = 0;
	145
	146	if (authctxt == NULL)
	147	fatal("input_userauth_request: no authctxt");
	148
	149	user = packet_get_string(NULL);
	150	service = packet_get_string(NULL);
	151	method = packet_get_string(NULL);
2980ea68	152
2980ea68	153	#ifdef GSSAPI
1b56ff3d	154	if (user[0] == '\0') {
c2397a66	155	debug("received empty username for %s", method);
34fee935	156	if (strcmp(method, "external-keyx") == 0 \|\|
34fee935	157	strcmp(method, "gssapi-keyex") == 0) {
c2397a66	158	char *lname = NULL;
	159	PRIVSEP(ssh_gssapi_localname(&lname));
	160	if (lname && lname[0] != '\0') {
	161	xfree(user);
	162	user = lname;
	163	debug("set username to %s from gssapi context", user);
57877bbc	164	} else {
c2397a66	165	debug("failed to set username from gssapi context");
c2397a66	166	}
ff2d7a98	167	}
	168	}
	169	#endif
2980ea68	170
c2397a66	171	debug("userauth-request for user %s service %s method %s",
1b56ff3d	172	user[0] ? user : "<implicit>", service, method);
3c0ef626	173	debug("attempt %d failures %d", authctxt->attempt, authctxt->failures);
	174
	175	if ((style = strchr(user, ':')) != NULL)
	176	*style++ = 0;
	177
416fd2a8	178	/* If first time or username changed or implicit username,
	179	setup/reset authentication context. */
	180	if ((authctxt->attempt++ == 0) \|\|
	181	(strcmp(user, authctxt->user) != 0) \|\|
	182	(strcmp(user, "") == 0)) {
ff2d7a98	183	if (authctxt->user) {
	184	xfree(authctxt->user);
	185	authctxt->user = NULL;
	186	}
34fee935	187	authctxt->valid = 0;
c2397a66	188	#ifdef GSSAPI
57877bbc	189	/* If we're going to set the username based on the
57877bbc	190	GSSAPI context later, then wait until then to
1b56ff3d	191	verify it. Just put in placeholders for now. */
	192	if ((strcmp(user, "") == 0) &&
	193	((strcmp(method, "gssapi") == 0) \|\|
	194	(strcmp(method, "gssapi-with-mic") == 0))) {
	195	authctxt->pw = fakepw();
	196	authctxt->user = xstrdup(user);
	197	} else {
c2397a66	198	#endif
2980ea68	199	authctxt->pw = PRIVSEP(getpwnamallow(user));
2a304a95	200	authctxt->user = xstrdup(user);
2980ea68	201	if (authctxt->pw && strcmp(service, "ssh-connection")==0) {
3c0ef626	202	authctxt->valid = 1;
	203	debug2("input_userauth_request: setting up authctxt for %s", user);
	204	#ifdef USE_PAM
70791e56	205	if (options.use_pam)
2a304a95	206	PRIVSEP(start_pam(authctxt));
3c0ef626	207	#endif
3c0ef626	208	} else {
1b56ff3d	209	logit("input_userauth_request: invalid user %s", user);
70791e56	210	authctxt->pw = fakepw();
3c0ef626	211	#ifdef USE_PAM
70791e56	212	if (options.use_pam)
2a304a95	213	PRIVSEP(start_pam(authctxt));
34fee935	214	#endif
	215	#ifdef SSH_AUDIT_EVENTS
	216	PRIVSEP(audit_event(SSH_INVALID_USER));
3c0ef626	217	#endif
3c0ef626	218	}
c2397a66	219	#ifdef GSSAPI
57877bbc	220	} /* endif for setting username based on GSSAPI context */
c2397a66	221	#endif
1b56ff3d	222	setproctitle("%s%s", authctxt->valid ? user : "unknown",
2980ea68	223	use_privsep ? " [net]" : "");
34fee935	224	#ifdef GSSAPI
	225	if (authctxt->attempt == 1) {
	226	#endif
	227	authctxt->service = xstrdup(service);
	228	authctxt->style = style ? xstrdup(style) : NULL;
	229	if (use_privsep)
2980ea68	230	mm_inform_authserv(service, style);
34fee935	231	#ifdef GSSAPI
	232	} /* if (authctxt->attempt == 1) */
	233	#endif
1b56ff3d	234	}
1b56ff3d	235	if (strcmp(service, authctxt->service) != 0) {
88928908	236	packet_disconnect("Change of service not allowed: "
	237	"(%s,%s) -> (%s,%s)",
	238	authctxt->user, authctxt->service, user, service);
3c0ef626	239	}
3c0ef626	240	/* reset state */
1e608e42	241	auth2_challenge_stop(authctxt);
5598e598	242
5598e598	243	#ifdef GSSAPI
1e608e42	244	dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_TOKEN, NULL);
1e608e42	245	dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_EXCHANGE_COMPLETE, NULL);
5598e598	246	#endif
5598e598	247
3c0ef626	248	authctxt->postponed = 0;
34fee935	249	authctxt->server_caused_failure = 0;
3c0ef626	250
	251	/* try to authenticate user */
	252	m = authmethod_lookup(method);
	253	if (m != NULL) {
	254	debug2("input_userauth_request: try method %s", method);
	255	authenticated = m->userauth(authctxt);
	256	}
	257	userauth_finish(authctxt, authenticated, method);
	258
	259	xfree(service);
	260	xfree(user);
	261	xfree(method);
	262	}
	263
	264	void
	265	userauth_finish(Authctxt authctxt, int authenticated, char method)
	266	{
	267	char *methods;
	268
	269	if (!authctxt->valid && authenticated)
	270	fatal("INTERNAL ERROR: authenticated invalid user %s",
	271	authctxt->user);
	272
	273	/* Special handling for root */
1c14df9e	274	if (authenticated && authctxt->pw->pw_uid == 0 &&
34fee935	275	!auth_root_allowed(method)) {
3c0ef626	276	authenticated = 0;
34fee935	277	#ifdef SSH_AUDIT_EVENTS
	278	PRIVSEP(audit_event(SSH_LOGIN_ROOT_DENIED));
	279	#endif
	280	}
3c0ef626	281
3c0ef626	282	#ifdef USE_PAM
34fee935	283	if (options.use_pam && authenticated) {
	284	if (!PRIVSEP(do_pam_account())) {
	285	/* if PAM returned a message, send it to the user */
	286	if (buffer_len(&loginmsg) > 0) {
	287	buffer_append(&loginmsg, "\0", 1);
	288	userauth_send_banner(buffer_ptr(&loginmsg));
	289	packet_write_wait();
	290	}
	291	fatal("Access denied for user %s by PAM account "
	292	"configuration", authctxt->user);
	293	}
	294	}
70791e56	295	#endif
3c0ef626	296
e54b3d7c	297	#ifdef _UNICOS
	298	if (authenticated && cray_access_denied(authctxt->user)) {
	299	authenticated = 0;
	300	fatal("Access denied for user %s.",authctxt->user);
	301	}
	302	#endif /* _UNICOS */
	303
3c0ef626	304	/* Log before sending the reply */
	305	auth_log(authctxt, authenticated, method, " ssh2");
	306
	307	if (authctxt->postponed)
	308	return;
	309
	310	/* XXX todo: check if multiple auth methods are needed */
	311	if (authenticated == 1) {
	312	/* turn off userauth */
1e608e42	313	dispatch_set(SSH2_MSG_USERAUTH_REQUEST, &dispatch_protocol_ignore);
3c0ef626	314	packet_start(SSH2_MSG_USERAUTH_SUCCESS);
	315	packet_send();
	316	packet_write_wait();
	317	/* now we can break out */
	318	authctxt->success = 1;
	319	} else {
34fee935	320	/* Dont count server configuration issues against the client */
	321	if (!authctxt->server_caused_failure &&
	322	authctxt->failures++ > options.max_authtries) {
	323	#ifdef SSH_AUDIT_EVENTS
	324	PRIVSEP(audit_event(SSH_LOGIN_EXCEED_MAXTRIES));
	325	#endif
3c0ef626	326	packet_disconnect(AUTH_FAIL_MSG, authctxt->user);
34fee935	327	}
3c0ef626	328	methods = authmethods_get();
	329	packet_start(SSH2_MSG_USERAUTH_FAILURE);
	330	packet_put_cstring(methods);
	331	packet_put_char(0); /* XXX partial success, unused */
	332	packet_send();
	333	packet_write_wait();
	334	xfree(methods);
	335	}
	336	}
	337
3c0ef626	338	#define DELIM ","
	339
	340	static char *
	341	authmethods_get(void)
	342	{
1e608e42	343	Buffer b;
3c0ef626	344	char *list;
ff2d7a98	345	int i;
3c0ef626	346
1e608e42	347	buffer_init(&b);
ff2d7a98	348	for (i = 0; authmethods[i] != NULL; i++) {
ff2d7a98	349	if (strcmp(authmethods[i]->name, "none") == 0)
3c0ef626	350	continue;
ff2d7a98	351	if (authmethods[i]->enabled != NULL &&
ff2d7a98	352	*(authmethods[i]->enabled) != 0) {
1e608e42	353	if (buffer_len(&b) > 0)
1e608e42	354	buffer_append(&b, ",", 1);
ff2d7a98	355	buffer_append(&b, authmethods[i]->name,
ff2d7a98	356	strlen(authmethods[i]->name));
3c0ef626	357	}
3c0ef626	358	}
1e608e42	359	buffer_append(&b, "\0", 1);
	360	list = xstrdup(buffer_ptr(&b));
	361	buffer_free(&b);
3c0ef626	362	return list;
	363	}
	364
	365	static Authmethod *
	366	authmethod_lookup(const char *name)
	367	{
ff2d7a98	368	int i;
ff2d7a98	369
3c0ef626	370	if (name != NULL)
ff2d7a98	371	for (i = 0; authmethods[i] != NULL; i++)
	372	if (authmethods[i]->enabled != NULL &&
	373	*(authmethods[i]->enabled) != 0 &&
	374	strcmp(name, authmethods[i]->name) == 0)
	375	return authmethods[i];
	376	debug2("Unrecognized authentication method name: %s",
	377	name ? name : "NULL");
3c0ef626	378	return NULL;
3c0ef626	379	}