[openssh.git] / auth-krb4.c

/*
 * Copyright (c) 1999 Dug Song.  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 "packet.h"
#include "xmalloc.h"
#include "ssh.h"
#include "servconf.h"

RCSID("$OpenBSD: auth-krb4.c,v 1.19 2000/10/03 18:03:02 markus Exp $");

#ifdef KRB4
char *ticket = NULL;

extern ServerOptions options;

/*
 * try krb4 authentication,
 * return 1 on success, 0 on failure, -1 if krb4 is not available
 */

int
auth_krb4_password(struct passwd * pw, const char *password)
{
	AUTH_DAT adata;
	KTEXT_ST tkt;
	struct hostent *hp;
	unsigned long faddr;
	char localhost[MAXHOSTNAMELEN];
	char phost[INST_SZ];
	char realm[REALM_SZ];
	int r;

	/*
	 * Try Kerberos password authentication only for non-root
	 * users and only if Kerberos is installed.
	 */
	if (pw->pw_uid != 0 && krb_get_lrealm(realm, 1) == KSUCCESS) {

		/* Set up our ticket file. */
		if (!krb4_init(pw->pw_uid)) {
			log("Couldn't initialize Kerberos ticket file for %s!",
			    pw->pw_name);
			goto kerberos_auth_failure;
		}
		/* Try to get TGT using our password. */
		r = krb_get_pw_in_tkt((char *) pw->pw_name, "",
		    realm, "krbtgt", realm,
		    DEFAULT_TKT_LIFE, (char *) password);
		if (r != INTK_OK) {
			packet_send_debug("Kerberos V4 password "
			    "authentication for %s failed: %s",
			    pw->pw_name, krb_err_txt[r]);
			goto kerberos_auth_failure;
		}
		/* Successful authentication. */
		chown(tkt_string(), pw->pw_uid, pw->pw_gid);

		/*
		 * Now that we have a TGT, try to get a local
		 * "rcmd" ticket to ensure that we are not talking
		 * to a bogus Kerberos server.
		 */
		(void) gethostname(localhost, sizeof(localhost));
		(void) strlcpy(phost, (char *) krb_get_phost(localhost),
		    INST_SZ);
		r = krb_mk_req(&tkt, KRB4_SERVICE_NAME, phost, realm, 33);

		if (r == KSUCCESS) {
			if (!(hp = gethostbyname(localhost))) {
				log("Couldn't get local host address!");
				goto kerberos_auth_failure;
			}
			memmove((void *) &faddr, (void *) hp->h_addr,
			    sizeof(faddr));

			/* Verify our "rcmd" ticket. */
			r = krb_rd_req(&tkt, KRB4_SERVICE_NAME, phost,
			    faddr, &adata, "");
			if (r == RD_AP_UNDEC) {
				/*
				 * Probably didn't have a srvtab on
				 * localhost. Disallow login.
				 */
				log("Kerberos V4 TGT for %s unverifiable, "
				    "no srvtab installed? krb_rd_req: %s",
				    pw->pw_name, krb_err_txt[r]);
				goto kerberos_auth_failure;
			} else if (r != KSUCCESS) {
				log("Kerberos V4 %s ticket unverifiable: %s",
				    KRB4_SERVICE_NAME, krb_err_txt[r]);
				goto kerberos_auth_failure;
			}
		} else if (r == KDC_PR_UNKNOWN) {
			/*
			 * Disallow login if no rcmd service exists, and
			 * log the error.
			 */
			log("Kerberos V4 TGT for %s unverifiable: %s; %s.%s "
			    "not registered, or srvtab is wrong?", pw->pw_name,
			krb_err_txt[r], KRB4_SERVICE_NAME, phost);
			goto kerberos_auth_failure;
		} else {
			/*
			 * TGT is bad, forget it. Possibly spoofed!
			 */
			packet_send_debug("WARNING: Kerberos V4 TGT "
			    "possibly spoofed for %s: %s",
			    pw->pw_name, krb_err_txt[r]);
			goto kerberos_auth_failure;
		}

		/* Authentication succeeded. */
		return 1;

kerberos_auth_failure:
		krb4_cleanup_proc(NULL);

		if (!options.kerberos_or_local_passwd)
			return 0;
	} else {
		/* Logging in as root or no local Kerberos realm. */
		packet_send_debug("Unable to authenticate to Kerberos.");
	}
	/* Fall back to ordinary passwd authentication. */
	return -1;
}

void
krb4_cleanup_proc(void *ignore)
{
	debug("krb4_cleanup_proc called");
	if (ticket) {
		(void) dest_tkt();
		xfree(ticket);
		ticket = NULL;
	}
}

int
krb4_init(uid_t uid)
{
	static int cleanup_registered = 0;
	const char *tkt_root = TKT_ROOT;
	struct stat st;
	int fd;

	if (!ticket) {
		/* Set unique ticket string manually since we're still root. */
		ticket = xmalloc(MAXPATHLEN);
#ifdef AFS
		if (lstat("/ticket", &st) != -1)
			tkt_root = "/ticket/";
#endif /* AFS */
		snprintf(ticket, MAXPATHLEN, "%s%u_%d", tkt_root, uid, getpid());
		(void) krb_set_tkt_string(ticket);
	}
	/* Register ticket cleanup in case of fatal error. */
	if (!cleanup_registered) {
		fatal_add_cleanup(krb4_cleanup_proc, NULL);
		cleanup_registered = 1;
	}
	/* Try to create our ticket file. */
	if ((fd = mkstemp(ticket)) != -1) {
		close(fd);
		return 1;
	}
	/* Ticket file exists - make sure user owns it (just passed ticket). */
	if (lstat(ticket, &st) != -1) {
		if (st.st_mode == (S_IFREG | S_IRUSR | S_IWUSR) &&
		    st.st_uid == uid)
			return 1;
	}
	/* Failure - cancel cleanup function, leaving bad ticket for inspection. */
	log("WARNING: bad ticket file %s", ticket);
	fatal_remove_cleanup(krb4_cleanup_proc, NULL);
	cleanup_registered = 0;
	xfree(ticket);
	ticket = NULL;

	return 0;
}

int
auth_krb4(const char *server_user, KTEXT auth, char **client)
{
	AUTH_DAT adat = {0};
	KTEXT_ST reply;
	char instance[INST_SZ];
	int r, s;
	socklen_t slen;
	u_int cksum;
	Key_schedule schedule;
	struct sockaddr_in local, foreign;

	s = packet_get_connection_in();

	slen = sizeof(local);
	memset(&local, 0, sizeof(local));
	if (getsockname(s, (struct sockaddr *) & local, &slen) < 0)
		debug("getsockname failed: %.100s", strerror(errno));
	slen = sizeof(foreign);
	memset(&foreign, 0, sizeof(foreign));
	if (getpeername(s, (struct sockaddr *) & foreign, &slen) < 0) {
		debug("getpeername failed: %.100s", strerror(errno));
		fatal_cleanup();
	}
	instance[0] = '*';
	instance[1] = 0;

	/* Get the encrypted request, challenge, and session key. */
	if ((r = krb_rd_req(auth, KRB4_SERVICE_NAME, instance, 0, &adat, ""))) {
		packet_send_debug("Kerberos V4 krb_rd_req: %.100s", krb_err_txt[r]);
		return 0;
	}
	des_key_sched((des_cblock *) adat.session, schedule);

	*client = xmalloc(MAX_K_NAME_SZ);
	(void) snprintf(*client, MAX_K_NAME_SZ, "%s%s%s@%s", adat.pname,
	    *adat.pinst ? "." : "", adat.pinst, adat.prealm);

	/* Check ~/.klogin authorization now. */
	if (kuserok(&adat, (char *) server_user) != KSUCCESS) {
		packet_send_debug("Kerberos V4 .klogin authorization failed!");
		log("Kerberos V4 .klogin authorization failed for %s to account %s",
		    *client, server_user);
		xfree(*client);
		return 0;
	}
	/* Increment the checksum, and return it encrypted with the
	   session key. */
	cksum = adat.checksum + 1;
	cksum = htonl(cksum);

	/* If we can't successfully encrypt the checksum, we send back an
	   empty message, admitting our failure. */
	if ((r = krb_mk_priv((u_char *) & cksum, reply.dat, sizeof(cksum) + 1,
	    schedule, &adat.session, &local, &foreign)) < 0) {
		packet_send_debug("Kerberos V4 mk_priv: (%d) %s", r, krb_err_txt[r]);
		reply.dat[0] = 0;
		reply.length = 0;
	} else
		reply.length = r;

	/* Clear session key. */
	memset(&adat.session, 0, sizeof(&adat.session));

	packet_start(SSH_SMSG_AUTH_KERBEROS_RESPONSE);
	packet_put_string((char *) reply.dat, reply.length);
	packet_send();
	packet_write_wait();
	return 1;
}
#endif /* KRB4 */

#ifdef AFS
int
auth_kerberos_tgt(struct passwd *pw, const char *string)
{
	CREDENTIALS creds;

	if (pw == NULL)
		goto auth_kerberos_tgt_failure;
	if (!radix_to_creds(string, &creds)) {
		log("Protocol error decoding Kerberos V4 tgt");
		packet_send_debug("Protocol error decoding Kerberos V4 tgt");
		goto auth_kerberos_tgt_failure;
	}
	if (strncmp(creds.service, "", 1) == 0)	/* backward compatibility */
		strlcpy(creds.service, "krbtgt", sizeof creds.service);

	if (strcmp(creds.service, "krbtgt")) {
		log("Kerberos V4 tgt (%s%s%s@%s) rejected for %s", creds.pname,
		    creds.pinst[0] ? "." : "", creds.pinst, creds.realm,
		    pw->pw_name);
		packet_send_debug("Kerberos V4 tgt (%s%s%s@%s) rejected for %s",
		    creds.pname, creds.pinst[0] ? "." : "", creds.pinst,
		    creds.realm, pw->pw_name);
		goto auth_kerberos_tgt_failure;
	}
	if (!krb4_init(pw->pw_uid))
		goto auth_kerberos_tgt_failure;

	if (in_tkt(creds.pname, creds.pinst) != KSUCCESS)
		goto auth_kerberos_tgt_failure;

	if (save_credentials(creds.service, creds.instance, creds.realm,
	    creds.session, creds.lifetime, creds.kvno,
	    &creds.ticket_st, creds.issue_date) != KSUCCESS) {
		packet_send_debug("Kerberos V4 tgt refused: couldn't save credentials");
		goto auth_kerberos_tgt_failure;
	}
	/* Successful authentication, passed all checks. */
	chown(tkt_string(), pw->pw_uid, pw->pw_gid);

	packet_send_debug("Kerberos V4 tgt accepted (%s.%s@%s, %s%s%s@%s)",
	    creds.service, creds.instance, creds.realm, creds.pname,
	    creds.pinst[0] ? "." : "", creds.pinst, creds.realm);
	memset(&creds, 0, sizeof(creds));
	packet_start(SSH_SMSG_SUCCESS);
	packet_send();
	packet_write_wait();
	return 1;

auth_kerberos_tgt_failure:
	krb4_cleanup_proc(NULL);
	memset(&creds, 0, sizeof(creds));
	packet_start(SSH_SMSG_FAILURE);
	packet_send();
	packet_write_wait();
	return 0;
}

int
auth_afs_token(struct passwd *pw, const char *token_string)
{
	CREDENTIALS creds;
	uid_t uid;

	if (pw == NULL) {
		/* XXX fake protocol error */
		packet_send_debug("Protocol error decoding AFS token");
		packet_start(SSH_SMSG_FAILURE);
		packet_send();
		packet_write_wait();
		return 0;
	}
	if (!radix_to_creds(token_string, &creds)) {
		log("Protocol error decoding AFS token");
		packet_send_debug("Protocol error decoding AFS token");
		packet_start(SSH_SMSG_FAILURE);
		packet_send();
		packet_write_wait();
		return 0;
	}
	if (strncmp(creds.service, "", 1) == 0)	/* backward compatibility */
		strlcpy(creds.service, "afs", sizeof creds.service);

	if (strncmp(creds.pname, "AFS ID ", 7) == 0)
		uid = atoi(creds.pname + 7);
	else
		uid = pw->pw_uid;

	if (kafs_settoken(creds.realm, uid, &creds)) {
		log("AFS token (%s@%s) rejected for %s", creds.pname, creds.realm,
		    pw->pw_name);
		packet_send_debug("AFS token (%s@%s) rejected for %s", creds.pname,
		    creds.realm, pw->pw_name);
		memset(&creds, 0, sizeof(creds));
		packet_start(SSH_SMSG_FAILURE);
		packet_send();
		packet_write_wait();
		return 0;
	}
	packet_send_debug("AFS token accepted (%s@%s, %s@%s)", creds.service,
	    creds.realm, creds.pname, creds.realm);
	memset(&creds, 0, sizeof(creds));
	packet_start(SSH_SMSG_SUCCESS);
	packet_send();
	packet_write_wait();
	return 1;
}
#endif /* AFS */
Commit	Line	Data
8efc0c15	1	/*
bcbf86ec	2	* Copyright (c) 1999 Dug Song. 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.
5260325f	23	*/
8efc0c15	24
	25	#include "includes.h"
	26	#include "packet.h"
	27	#include "xmalloc.h"
	28	#include "ssh.h"
57112b5a	29	#include "servconf.h"
8efc0c15	30
94ec8c6b	31	RCSID("$OpenBSD: auth-krb4.c,v 1.19 2000/10/03 18:03:02 markus Exp $");
e5a0294f	32
8efc0c15	33	#ifdef KRB4
6a17f9c2	34	char *ticket = NULL;
6a17f9c2	35
57112b5a	36	extern ServerOptions options;
	37
	38	/*
	39	* try krb4 authentication,
	40	* return 1 on success, 0 on failure, -1 if krb4 is not available
	41	*/
	42
6ae2364d	43	int
57112b5a	44	auth_krb4_password(struct passwd * pw, const char *password)
	45	{
	46	AUTH_DAT adata;
	47	KTEXT_ST tkt;
	48	struct hostent *hp;
	49	unsigned long faddr;
	50	char localhost[MAXHOSTNAMELEN];
	51	char phost[INST_SZ];
	52	char realm[REALM_SZ];
	53	int r;
	54
	55	/*
	56	* Try Kerberos password authentication only for non-root
	57	* users and only if Kerberos is installed.
	58	*/
	59	if (pw->pw_uid != 0 && krb_get_lrealm(realm, 1) == KSUCCESS) {
	60
	61	/* Set up our ticket file. */
	62	if (!krb4_init(pw->pw_uid)) {
	63	log("Couldn't initialize Kerberos ticket file for %s!",
	64	pw->pw_name);
	65	goto kerberos_auth_failure;
	66	}
	67	/* Try to get TGT using our password. */
	68	r = krb_get_pw_in_tkt((char *) pw->pw_name, "",
	69	realm, "krbtgt", realm,
	70	DEFAULT_TKT_LIFE, (char *) password);
	71	if (r != INTK_OK) {
	72	packet_send_debug("Kerberos V4 password "
	73	"authentication for %s failed: %s",
	74	pw->pw_name, krb_err_txt[r]);
	75	goto kerberos_auth_failure;
	76	}
	77	/* Successful authentication. */
	78	chown(tkt_string(), pw->pw_uid, pw->pw_gid);
	79
	80	/*
	81	* Now that we have a TGT, try to get a local
	82	* "rcmd" ticket to ensure that we are not talking
	83	* to a bogus Kerberos server.
	84	*/
	85	(void) gethostname(localhost, sizeof(localhost));
	86	(void) strlcpy(phost, (char *) krb_get_phost(localhost),
	87	INST_SZ);
	88	r = krb_mk_req(&tkt, KRB4_SERVICE_NAME, phost, realm, 33);
	89
	90	if (r == KSUCCESS) {
	91	if (!(hp = gethostbyname(localhost))) {
	92	log("Couldn't get local host address!");
	93	goto kerberos_auth_failure;
	94	}
	95	memmove((void ) &faddr, (void ) hp->h_addr,
	96	sizeof(faddr));
	97
	98	/* Verify our "rcmd" ticket. */
	99	r = krb_rd_req(&tkt, KRB4_SERVICE_NAME, phost,
	100	faddr, &adata, "");
	101	if (r == RD_AP_UNDEC) {
	102	/*
	103	* Probably didn't have a srvtab on
c345cf9d	104	* localhost. Disallow login.
57112b5a	105	*/
	106	log("Kerberos V4 TGT for %s unverifiable, "
	107	"no srvtab installed? krb_rd_req: %s",
	108	pw->pw_name, krb_err_txt[r]);
c345cf9d	109	goto kerberos_auth_failure;
57112b5a	110	} else if (r != KSUCCESS) {
	111	log("Kerberos V4 %s ticket unverifiable: %s",
	112	KRB4_SERVICE_NAME, krb_err_txt[r]);
	113	goto kerberos_auth_failure;
	114	}
	115	} else if (r == KDC_PR_UNKNOWN) {
	116	/*
c345cf9d	117	* Disallow login if no rcmd service exists, and
57112b5a	118	* log the error.
	119	*/
	120	log("Kerberos V4 TGT for %s unverifiable: %s; %s.%s "
	121	"not registered, or srvtab is wrong?", pw->pw_name,
	122	krb_err_txt[r], KRB4_SERVICE_NAME, phost);
c345cf9d	123	goto kerberos_auth_failure;
57112b5a	124	} else {
	125	/*
	126	* TGT is bad, forget it. Possibly spoofed!
	127	*/
	128	packet_send_debug("WARNING: Kerberos V4 TGT "
	129	"possibly spoofed for %s: %s",
	130	pw->pw_name, krb_err_txt[r]);
	131	goto kerberos_auth_failure;
	132	}
	133
	134	/* Authentication succeeded. */
	135	return 1;
	136
	137	kerberos_auth_failure:
	138	krb4_cleanup_proc(NULL);
	139
	140	if (!options.kerberos_or_local_passwd)
	141	return 0;
	142	} else {
	143	/* Logging in as root or no local Kerberos realm. */
	144	packet_send_debug("Unable to authenticate to Kerberos.");
	145	}
	146	/* Fall back to ordinary passwd authentication. */
	147	return -1;
	148	}
	149
6a17f9c2	150	void
	151	krb4_cleanup_proc(void *ignore)
	152	{
5260325f	153	debug("krb4_cleanup_proc called");
	154	if (ticket) {
	155	(void) dest_tkt();
	156	xfree(ticket);
	157	ticket = NULL;
	158	}
6a17f9c2	159	}
6a17f9c2	160
6ae2364d	161	int
5260325f	162	krb4_init(uid_t uid)
8efc0c15	163	{
5260325f	164	static int cleanup_registered = 0;
4fe2af09	165	const char *tkt_root = TKT_ROOT;
5260325f	166	struct stat st;
	167	int fd;
	168
	169	if (!ticket) {
	170	/* Set unique ticket string manually since we're still root. */
	171	ticket = xmalloc(MAXPATHLEN);
8efc0c15	172	#ifdef AFS
5260325f	173	if (lstat("/ticket", &st) != -1)
5260325f	174	tkt_root = "/ticket/";
8efc0c15	175	#endif /* AFS */
14a9a859	176	snprintf(ticket, MAXPATHLEN, "%s%u_%d", tkt_root, uid, getpid());
5260325f	177	(void) krb_set_tkt_string(ticket);
	178	}
	179	/* Register ticket cleanup in case of fatal error. */
	180	if (!cleanup_registered) {
	181	fatal_add_cleanup(krb4_cleanup_proc, NULL);
	182	cleanup_registered = 1;
	183	}
	184	/* Try to create our ticket file. */
	185	if ((fd = mkstemp(ticket)) != -1) {
	186	close(fd);
	187	return 1;
	188	}
	189	/* Ticket file exists - make sure user owns it (just passed ticket). */
	190	if (lstat(ticket, &st) != -1) {
	191	if (st.st_mode == (S_IFREG \| S_IRUSR \| S_IWUSR) &&
	192	st.st_uid == uid)
	193	return 1;
	194	}
	195	/* Failure - cancel cleanup function, leaving bad ticket for inspection. */
	196	log("WARNING: bad ticket file %s", ticket);
	197	fatal_remove_cleanup(krb4_cleanup_proc, NULL);
	198	cleanup_registered = 0;
	199	xfree(ticket);
	200	ticket = NULL;
	201
	202	return 0;
8efc0c15	203	}
8efc0c15	204
6ae2364d	205	int
5260325f	206	auth_krb4(const char server_user, KTEXT auth, char *client)
8efc0c15	207	{
5260325f	208	AUTH_DAT adat = {0};
	209	KTEXT_ST reply;
	210	char instance[INST_SZ];
	211	int r, s;
610cd5c6	212	socklen_t slen;
5260325f	213	u_int cksum;
	214	Key_schedule schedule;
	215	struct sockaddr_in local, foreign;
	216
	217	s = packet_get_connection_in();
	218
610cd5c6	219	slen = sizeof(local);
5260325f	220	memset(&local, 0, sizeof(local));
610cd5c6	221	if (getsockname(s, (struct sockaddr *) & local, &slen) < 0)
5260325f	222	debug("getsockname failed: %.100s", strerror(errno));
610cd5c6	223	slen = sizeof(foreign);
5260325f	224	memset(&foreign, 0, sizeof(foreign));
610cd5c6	225	if (getpeername(s, (struct sockaddr *) & foreign, &slen) < 0) {
5260325f	226	debug("getpeername failed: %.100s", strerror(errno));
	227	fatal_cleanup();
	228	}
	229	instance[0] = '*';
	230	instance[1] = 0;
	231
	232	/* Get the encrypted request, challenge, and session key. */
	233	if ((r = krb_rd_req(auth, KRB4_SERVICE_NAME, instance, 0, &adat, ""))) {
	234	packet_send_debug("Kerberos V4 krb_rd_req: %.100s", krb_err_txt[r]);
	235	return 0;
	236	}
	237	des_key_sched((des_cblock *) adat.session, schedule);
	238
	239	*client = xmalloc(MAX_K_NAME_SZ);
	240	(void) snprintf(*client, MAX_K_NAME_SZ, "%s%s%s@%s", adat.pname,
	241	*adat.pinst ? "." : "", adat.pinst, adat.prealm);
	242
	243	/* Check ~/.klogin authorization now. */
	244	if (kuserok(&adat, (char *) server_user) != KSUCCESS) {
	245	packet_send_debug("Kerberos V4 .klogin authorization failed!");
	246	log("Kerberos V4 .klogin authorization failed for %s to account %s",
	247	*client, server_user);
	248	xfree(*client);
	249	return 0;
	250	}
	251	/* Increment the checksum, and return it encrypted with the
	252	session key. */
	253	cksum = adat.checksum + 1;
	254	cksum = htonl(cksum);
	255
	256	/* If we can't successfully encrypt the checksum, we send back an
	257	empty message, admitting our failure. */
	258	if ((r = krb_mk_priv((u_char *) & cksum, reply.dat, sizeof(cksum) + 1,
	259	schedule, &adat.session, &local, &foreign)) < 0) {
	260	packet_send_debug("Kerberos V4 mk_priv: (%d) %s", r, krb_err_txt[r]);
	261	reply.dat[0] = 0;
	262	reply.length = 0;
	263	} else
	264	reply.length = r;
	265
	266	/* Clear session key. */
	267	memset(&adat.session, 0, sizeof(&adat.session));
	268
	269	packet_start(SSH_SMSG_AUTH_KERBEROS_RESPONSE);
	270	packet_put_string((char *) reply.dat, reply.length);
	271	packet_send();
	272	packet_write_wait();
	273	return 1;
8efc0c15	274	}
	275	#endif /* KRB4 */
	276
	277	#ifdef AFS
6ae2364d	278	int
5260325f	279	auth_kerberos_tgt(struct passwd pw, const char string)
8efc0c15	280	{
5260325f	281	CREDENTIALS creds;
5260325f	282
94ec8c6b	283	if (pw == NULL)
94ec8c6b	284	goto auth_kerberos_tgt_failure;
5260325f	285	if (!radix_to_creds(string, &creds)) {
	286	log("Protocol error decoding Kerberos V4 tgt");
	287	packet_send_debug("Protocol error decoding Kerberos V4 tgt");
	288	goto auth_kerberos_tgt_failure;
	289	}
	290	if (strncmp(creds.service, "", 1) == 0) /* backward compatibility */
	291	strlcpy(creds.service, "krbtgt", sizeof creds.service);
	292
	293	if (strcmp(creds.service, "krbtgt")) {
	294	log("Kerberos V4 tgt (%s%s%s@%s) rejected for %s", creds.pname,
	295	creds.pinst[0] ? "." : "", creds.pinst, creds.realm,
	296	pw->pw_name);
	297	packet_send_debug("Kerberos V4 tgt (%s%s%s@%s) rejected for %s",
	298	creds.pname, creds.pinst[0] ? "." : "", creds.pinst,
	299	creds.realm, pw->pw_name);
	300	goto auth_kerberos_tgt_failure;
	301	}
	302	if (!krb4_init(pw->pw_uid))
	303	goto auth_kerberos_tgt_failure;
	304
	305	if (in_tkt(creds.pname, creds.pinst) != KSUCCESS)
	306	goto auth_kerberos_tgt_failure;
	307
	308	if (save_credentials(creds.service, creds.instance, creds.realm,
	309	creds.session, creds.lifetime, creds.kvno,
	310	&creds.ticket_st, creds.issue_date) != KSUCCESS) {
	311	packet_send_debug("Kerberos V4 tgt refused: couldn't save credentials");
	312	goto auth_kerberos_tgt_failure;
	313	}
	314	/* Successful authentication, passed all checks. */
	315	chown(tkt_string(), pw->pw_uid, pw->pw_gid);
	316
	317	packet_send_debug("Kerberos V4 tgt accepted (%s.%s@%s, %s%s%s@%s)",
	318	creds.service, creds.instance, creds.realm, creds.pname,
	319	creds.pinst[0] ? "." : "", creds.pinst, creds.realm);
	320	memset(&creds, 0, sizeof(creds));
	321	packet_start(SSH_SMSG_SUCCESS);
	322	packet_send();
	323	packet_write_wait();
	324	return 1;
	325
	326	auth_kerberos_tgt_failure:
	327	krb4_cleanup_proc(NULL);
	328	memset(&creds, 0, sizeof(creds));
	329	packet_start(SSH_SMSG_FAILURE);
	330	packet_send();
	331	packet_write_wait();
	332	return 0;
8efc0c15	333	}
8efc0c15	334
6ae2364d	335	int
5260325f	336	auth_afs_token(struct passwd pw, const char token_string)
8efc0c15	337	{
5260325f	338	CREDENTIALS creds;
94ec8c6b	339	uid_t uid;
5260325f	340
94ec8c6b	341	if (pw == NULL) {
	342	/* XXX fake protocol error */
	343	packet_send_debug("Protocol error decoding AFS token");
	344	packet_start(SSH_SMSG_FAILURE);
	345	packet_send();
	346	packet_write_wait();
	347	return 0;
	348	}
5260325f	349	if (!radix_to_creds(token_string, &creds)) {
	350	log("Protocol error decoding AFS token");
	351	packet_send_debug("Protocol error decoding AFS token");
	352	packet_start(SSH_SMSG_FAILURE);
	353	packet_send();
	354	packet_write_wait();
	355	return 0;
	356	}
	357	if (strncmp(creds.service, "", 1) == 0) /* backward compatibility */
	358	strlcpy(creds.service, "afs", sizeof creds.service);
	359
	360	if (strncmp(creds.pname, "AFS ID ", 7) == 0)
	361	uid = atoi(creds.pname + 7);
94ec8c6b	362	else
94ec8c6b	363	uid = pw->pw_uid;
5260325f	364
	365	if (kafs_settoken(creds.realm, uid, &creds)) {
	366	log("AFS token (%s@%s) rejected for %s", creds.pname, creds.realm,
	367	pw->pw_name);
	368	packet_send_debug("AFS token (%s@%s) rejected for %s", creds.pname,
	369	creds.realm, pw->pw_name);
	370	memset(&creds, 0, sizeof(creds));
	371	packet_start(SSH_SMSG_FAILURE);
	372	packet_send();
	373	packet_write_wait();
	374	return 0;
	375	}
	376	packet_send_debug("AFS token accepted (%s@%s, %s@%s)", creds.service,
	377	creds.realm, creds.pname, creds.realm);
	378	memset(&creds, 0, sizeof(creds));
	379	packet_start(SSH_SMSG_SUCCESS);
	380	packet_send();
	381	packet_write_wait();
	382	return 1;
8efc0c15	383	}
8efc0c15	384	#endif /* AFS */