xref: /netbsd-src/crypto/external/bsd/heimdal/dist/kcm/acquire.c (revision d3273b5b76f5afaafe308cead5511dbb8df8c5e9)
1 /*	$NetBSD: acquire.c,v 1.2 2017/01/28 21:31:44 christos Exp $	*/
2 
3 /*
4  * Copyright (c) 2005, PADL Software Pty Ltd.
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  *
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  *
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * 3. Neither the name of PADL Software nor the names of its contributors
19  *    may be used to endorse or promote products derived from this software
20  *    without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY PADL SOFTWARE AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL PADL SOFTWARE OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  */
34 
35 #include "kcm_locl.h"
36 
37 /*
38  * Get a new ticket using a keytab/cached key and swap it into
39  * an existing redentials cache
40  */
41 
42 krb5_error_code
kcm_ccache_acquire(krb5_context context,kcm_ccache ccache,krb5_creds ** credp)43 kcm_ccache_acquire(krb5_context context,
44 		   kcm_ccache ccache,
45 		   krb5_creds **credp)
46 {
47     krb5_error_code ret = 0;
48     krb5_creds cred;
49     krb5_const_realm realm;
50     krb5_get_init_creds_opt *opt = NULL;
51     krb5_ccache_data ccdata;
52     char *in_tkt_service = NULL;
53     const char *estr;
54 
55     *credp = NULL;
56     memset(&cred, 0, sizeof(cred));
57 
58     KCM_ASSERT_VALID(ccache);
59 
60     /* We need a cached key or keytab to acquire credentials */
61     if (ccache->flags & KCM_FLAGS_USE_CACHED_KEY) {
62 	if (ccache->key.keyblock.keyvalue.length == 0)
63 	    krb5_abortx(context,
64 			"kcm_ccache_acquire: KCM_FLAGS_USE_CACHED_KEY without key");
65     } else if (ccache->flags & KCM_FLAGS_USE_KEYTAB) {
66 	if (ccache->key.keytab == NULL)
67 	    krb5_abortx(context,
68 			"kcm_ccache_acquire: KCM_FLAGS_USE_KEYTAB without keytab");
69     } else {
70 	kcm_log(0, "Cannot acquire initial credentials for cache %s without key",
71 		ccache->name);
72 	return KRB5_FCC_INTERNAL;
73     }
74 
75     HEIMDAL_MUTEX_lock(&ccache->mutex);
76 
77     /* Fake up an internal ccache */
78     kcm_internal_ccache(context, ccache, &ccdata);
79 
80     /* Now, actually acquire the creds */
81     if (ccache->server != NULL) {
82 	ret = krb5_unparse_name(context, ccache->server, &in_tkt_service);
83 	if (ret) {
84 	    estr = krb5_get_error_message(context, ret);
85 	    kcm_log(0, "Failed to unparse service principal name for cache %s: %s",
86 		    ccache->name, estr);
87 	    krb5_free_error_message(context, estr);
88 	    goto out;
89 	}
90     }
91 
92     realm = krb5_principal_get_realm(context, ccache->client);
93 
94     ret = krb5_get_init_creds_opt_alloc(context, &opt);
95     if (ret)
96 	goto out;
97     krb5_get_init_creds_opt_set_default_flags(context, "kcm", realm, opt);
98     if (ccache->tkt_life != 0)
99 	krb5_get_init_creds_opt_set_tkt_life(opt, ccache->tkt_life);
100     if (ccache->renew_life != 0)
101 	krb5_get_init_creds_opt_set_renew_life(opt, ccache->renew_life);
102 
103     if (ccache->flags & KCM_FLAGS_USE_CACHED_KEY) {
104 	ret = krb5_get_init_creds_keyblock(context,
105 					   &cred,
106 					   ccache->client,
107 					   &ccache->key.keyblock,
108 					   0,
109 					   in_tkt_service,
110 					   opt);
111     } else {
112 	/* loosely based on lib/krb5/init_creds_pw.c */
113 	ret = krb5_get_init_creds_keytab(context,
114 					 &cred,
115 					 ccache->client,
116 					 ccache->key.keytab,
117 					 0,
118 					 in_tkt_service,
119 					 opt);
120     }
121 
122     if (ret) {
123 	estr = krb5_get_error_message(context, ret);
124 	kcm_log(0, "Failed to acquire credentials for cache %s: %s",
125 		ccache->name, estr);
126 	krb5_free_error_message(context, estr);
127 	goto out;
128     }
129 
130     /* Swap them in */
131     kcm_ccache_remove_creds_internal(context, ccache);
132 
133     ret = kcm_ccache_store_cred_internal(context, ccache, &cred, 0, credp);
134     if (ret) {
135 	estr = krb5_get_error_message(context, ret);
136 	kcm_log(0, "Failed to store credentials for cache %s: %s",
137 		ccache->name, estr);
138 	krb5_free_error_message(context, estr);
139 	krb5_free_cred_contents(context, &cred);
140 	goto out;
141     }
142 
143 out:
144     free(in_tkt_service);
145     if (opt)
146 	krb5_get_init_creds_opt_free(context, opt);
147 
148     HEIMDAL_MUTEX_unlock(&ccache->mutex);
149 
150     return ret;
151 }
152