xref: /netbsd-src/crypto/external/bsd/openssh/dist/auth2-krb5.c (revision c38e7cc395b1472a774ff828e46123de44c628e9)
1 /*	$NetBSD: auth2-krb5.c,v 1.7 2017/10/07 19:39:19 christos Exp $	*/
2 /*
3  * Copyright (c) 2003 Markus Friedl.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
15  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
16  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
17  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
18  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
19  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
20  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
21  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
23  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24  */
25 
26 #include "includes.h"
27 __RCSID("$NetBSD: auth2-krb5.c,v 1.7 2017/10/07 19:39:19 christos Exp $");
28 
29 #include <krb5.h>
30 #include <stdio.h>
31 
32 #include "ssh2.h"
33 #include "xmalloc.h"
34 #include "packet.h"
35 #include "log.h"
36 #include "key.h"
37 #include "buffer.h"
38 #include "hostfile.h"
39 #include "auth.h"
40 #ifdef GSSAPI
41 #include "ssh-gss.h"
42 #endif
43 #include "ssherr.h"
44 #include "monitor_wrap.h"
45 #include "misc.h"
46 #include "servconf.h"
47 
48 /* import */
49 extern ServerOptions options;
50 
51 static int
52 userauth_kerberos(struct ssh *ssh)
53 {
54 	krb5_data tkt, reply;
55 	size_t dlen;
56 	char *passwd;
57 	char *client = NULL;
58 	int authenticated = 0, r;
59 
60 	if ((r = sshpkt_get_cstring(ssh, &passwd, &dlen)) != 0 ||
61 	     (r = sshpkt_get_end(ssh)) != 0)
62 		 fatal("%s: %s", __func__, ssh_err(r));
63 
64 	tkt.data = passwd;
65 	tkt.length = dlen;
66 	if (PRIVSEP(auth_krb5(ssh->authctxt, &tkt, &client, &reply))) {
67 		authenticated = 1;
68 		if (reply.length)
69 			free(reply.data);
70 	}
71 	if (client)
72 		free(client);
73 	free(tkt.data);
74 	return (authenticated);
75 }
76 
77 Authmethod method_kerberos = {
78 	"kerberos-2@ssh.com",
79 	userauth_kerberos,
80 	&options.kerberos_authentication
81 };
82