client.c revision 178825 
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
36RCSID("$Id: client.c 20487 2007-04-21 06:25:06Z lha $");
37
38krb5_error_code
39kcm_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
63krb5_error_code
64kcm_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
94krb5_error_code
95kcm_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