xref: /freebsd/crypto/heimdal/kcm/client.c (revision 39beb93c3f8bdbf72a61fda42300b5ebed7390c8)
1 /*
2  * Copyright (c) 2005, PADL Software Pty Ltd.
3  * 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  *
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  *
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * 3. Neither the name of PADL Software nor the names of its contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY PADL SOFTWARE AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL PADL SOFTWARE OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  */
32 
33 #include "kcm_locl.h"
34 #include <pwd.h>
35 
36 RCSID("$Id: client.c 20487 2007-04-21 06:25:06Z lha $");
37 
38 krb5_error_code
39 kcm_ccache_resolve_client(krb5_context context,
40 			  kcm_client *client,
41 			  kcm_operation opcode,
42 			  const char *name,
43 			  kcm_ccache *ccache)
44 {
45     krb5_error_code ret;
46 
47     ret = kcm_ccache_resolve(context, name, ccache);
48     if (ret) {
49 	kcm_log(1, "Failed to resolve cache %s: %s",
50 		name, krb5_get_err_text(context, ret));
51 	return ret;
52     }
53 
54     ret = kcm_access(context, client, opcode, *ccache);
55     if (ret) {
56 	ret = KRB5_FCC_NOFILE; /* don't disclose */
57 	kcm_release_ccache(context, ccache);
58     }
59 
60     return ret;
61 }
62 
63 krb5_error_code
64 kcm_ccache_destroy_client(krb5_context context,
65 			  kcm_client *client,
66 			  const char *name)
67 {
68     krb5_error_code ret;
69     kcm_ccache ccache;
70 
71     ret = kcm_ccache_resolve(context, name, &ccache);
72     if (ret) {
73 	kcm_log(1, "Failed to resolve cache %s: %s",
74 		name, krb5_get_err_text(context, ret));
75 	return ret;
76     }
77 
78     ret = kcm_access(context, client, KCM_OP_DESTROY, ccache);
79     if (ret) {
80 	kcm_release_ccache(context, &ccache);
81 	return ret;
82     }
83 
84     ret = kcm_ccache_destroy(context, ccache->name);
85     if (ret == 0) {
86 	/* don't leave any events dangling */
87 	kcm_cleanup_events(context, ccache);
88     }
89 
90     kcm_release_ccache(context, &ccache);
91     return ret;
92 }
93 
94 krb5_error_code
95 kcm_ccache_new_client(krb5_context context,
96 		      kcm_client *client,
97 		      const char *name,
98 		      kcm_ccache *ccache_p)
99 {
100     krb5_error_code ret;
101     kcm_ccache ccache;
102 
103     /* We insist the ccache name starts with UID or UID: */
104     if (name_constraints != 0) {
105 	char prefix[64];
106 	size_t prefix_len;
107 	int bad = 1;
108 
109 	snprintf(prefix, sizeof(prefix), "%ld:", (long)client->uid);
110 	prefix_len = strlen(prefix);
111 
112 	if (strncmp(name, prefix, prefix_len) == 0)
113 	    bad = 0;
114 	else {
115 	    prefix[prefix_len - 1] = '\0';
116 	    if (strcmp(name, prefix) == 0)
117 		bad = 0;
118 	}
119 
120 	/* Allow root to create badly-named ccaches */
121 	if (bad && !CLIENT_IS_ROOT(client))
122 	    return KRB5_CC_BADNAME;
123     }
124 
125     ret = kcm_ccache_resolve(context, name, &ccache);
126     if (ret == 0) {
127 	if ((ccache->uid != client->uid ||
128 	     ccache->gid != client->gid) && !CLIENT_IS_ROOT(client))
129 	    return KRB5_FCC_PERM;
130     } else if (ret != KRB5_FCC_NOFILE && !(CLIENT_IS_ROOT(client) && ret == KRB5_FCC_PERM)) {
131 		return ret;
132     }
133 
134     if (ret == KRB5_FCC_NOFILE) {
135 	ret = kcm_ccache_new(context, name, &ccache);
136 	if (ret) {
137 	    kcm_log(1, "Failed to initialize cache %s: %s",
138 		    name, krb5_get_err_text(context, ret));
139 	    return ret;
140 	}
141 
142 	/* bind to current client */
143 	ccache->uid = client->uid;
144 	ccache->gid = client->gid;
145     } else {
146 	ret = kcm_zero_ccache_data(context, ccache);
147 	if (ret) {
148 	    kcm_log(1, "Failed to empty cache %s: %s",
149 		    name, krb5_get_err_text(context, ret));
150 	    kcm_release_ccache(context, &ccache);
151 	    return ret;
152 	}
153 	kcm_cleanup_events(context, ccache);
154     }
155 
156     ret = kcm_access(context, client, KCM_OP_INITIALIZE, ccache);
157     if (ret) {
158 	kcm_release_ccache(context, &ccache);
159 	kcm_ccache_destroy(context, name);
160 	return ret;
161     }
162 
163     /*
164      * Finally, if the user is root and the cache was created under
165      * another user's name, chown the cache to that user and their
166      * default gid.
167      */
168     if (CLIENT_IS_ROOT(client)) {
169 	unsigned long uid;
170 	int matches = sscanf(name,"%ld:",&uid);
171 	if (matches == 0)
172 	    matches = sscanf(name,"%ld",&uid);
173 	if (matches == 1) {
174 	    struct passwd *pwd = getpwuid(uid);
175 	    if (pwd != NULL) {
176 		gid_t gid = pwd->pw_gid;
177 		kcm_chown(context, client, ccache, uid, gid);
178 	    }
179 	}
180     }
181 
182     *ccache_p = ccache;
183     return 0;
184 }
185 
186