client.c revision 1.1.1.1 
1/*	$NetBSD: client.c,v 1.1.1.1 2011/04/13 18:14:36 elric Exp $	*/
2
3/*
4 * Copyright (c) 2005, PADL Software Pty Ltd.
5 * All rights reserved.
6 *
7 * Portions Copyright (c) 2009 Apple Inc. All rights reserved.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 *
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 *
16 * 2. Redistributions in binary form must reproduce the above copyright
17 *    notice, this list of conditions and the following disclaimer in the
18 *    documentation and/or other materials provided with the distribution.
19 *
20 * 3. Neither the name of PADL Software nor the names of its contributors
21 *    may be used to endorse or promote products derived from this software
22 *    without specific prior written permission.
23 *
24 * THIS SOFTWARE IS PROVIDED BY PADL SOFTWARE AND CONTRIBUTORS ``AS IS'' AND
25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED.  IN NO EVENT SHALL PADL SOFTWARE OR CONTRIBUTORS BE LIABLE
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * SUCH DAMAGE.
35 */
36
37#include "kcm_locl.h"
38#include <pwd.h>
39
40krb5_error_code
41kcm_ccache_resolve_client(krb5_context context,
42			  kcm_client *client,
43			  kcm_operation opcode,
44			  const char *name,
45			  kcm_ccache *ccache)
46{
47    krb5_error_code ret;
48
49    ret = kcm_ccache_resolve(context, name, ccache);
50    if (ret) {
51	kcm_log(1, "Failed to resolve cache %s: %s",
52		name, krb5_get_err_text(context, ret));
53	return ret;
54    }
55
56    ret = kcm_access(context, client, opcode, *ccache);
57    if (ret) {
58	ret = KRB5_FCC_NOFILE; /* don't disclose */
59	kcm_release_ccache(context, *ccache);
60    }
61
62    return ret;
63}
64
65krb5_error_code
66kcm_ccache_destroy_client(krb5_context context,
67			  kcm_client *client,
68			  const char *name)
69{
70    krb5_error_code ret;
71    kcm_ccache ccache;
72
73    ret = kcm_ccache_resolve(context, name, &ccache);
74    if (ret) {
75	kcm_log(1, "Failed to resolve cache %s: %s",
76		name, krb5_get_err_text(context, ret));
77	return ret;
78    }
79
80    ret = kcm_access(context, client, KCM_OP_DESTROY, ccache);
81    kcm_cleanup_events(context, ccache);
82    kcm_release_ccache(context, ccache);
83    if (ret)
84	return ret;
85
86    return kcm_ccache_destroy(context, name);
87}
88
89krb5_error_code
90kcm_ccache_new_client(krb5_context context,
91		      kcm_client *client,
92		      const char *name,
93		      kcm_ccache *ccache_p)
94{
95    krb5_error_code ret;
96    kcm_ccache ccache;
97
98    /* We insist the ccache name starts with UID or UID: */
99    if (name_constraints != 0) {
100	char prefix[64];
101	size_t prefix_len;
102	int bad = 1;
103
104	snprintf(prefix, sizeof(prefix), "%ld:", (long)client->uid);
105	prefix_len = strlen(prefix);
106
107	if (strncmp(name, prefix, prefix_len) == 0)
108	    bad = 0;
109	else {
110	    prefix[prefix_len - 1] = '\0';
111	    if (strcmp(name, prefix) == 0)
112		bad = 0;
113	}
114
115	/* Allow root to create badly-named ccaches */
116	if (bad && !CLIENT_IS_ROOT(client))
117	    return KRB5_CC_BADNAME;
118    }
119
120    ret = kcm_ccache_resolve(context, name, &ccache);
121    if (ret == 0) {
122	if ((ccache->uid != client->uid ||
123	     ccache->gid != client->gid) && !CLIENT_IS_ROOT(client))
124	    return KRB5_FCC_PERM;
125    } else if (ret != KRB5_FCC_NOFILE && !(CLIENT_IS_ROOT(client) && ret == KRB5_FCC_PERM)) {
126		return ret;
127    }
128
129    if (ret == KRB5_FCC_NOFILE) {
130	ret = kcm_ccache_new(context, name, &ccache);
131	if (ret) {
132	    kcm_log(1, "Failed to initialize cache %s: %s",
133		    name, krb5_get_err_text(context, ret));
134	    return ret;
135	}
136
137	/* bind to current client */
138	ccache->uid = client->uid;
139	ccache->gid = client->gid;
140	ccache->session = client->session;
141    } else {
142	ret = kcm_zero_ccache_data(context, ccache);
143	if (ret) {
144	    kcm_log(1, "Failed to empty cache %s: %s",
145		    name, krb5_get_err_text(context, ret));
146	    kcm_release_ccache(context, ccache);
147	    return ret;
148	}
149	kcm_cleanup_events(context, ccache);
150    }
151
152    ret = kcm_access(context, client, KCM_OP_INITIALIZE, ccache);
153    if (ret) {
154	kcm_release_ccache(context, ccache);
155	kcm_ccache_destroy(context, name);
156	return ret;
157    }
158
159    /*
160     * Finally, if the user is root and the cache was created under
161     * another user's name, chown the cache to that user and their
162     * default gid.
163     */
164    if (CLIENT_IS_ROOT(client)) {
165	unsigned long uid;
166	int matches = sscanf(name,"%ld:",&uid);
167	if (matches == 0)
168	    matches = sscanf(name,"%ld",&uid);
169	if (matches == 1) {
170	    struct passwd *pwd = getpwuid(uid);
171	    if (pwd != NULL) {
172		gid_t gid = pwd->pw_gid;
173		kcm_chown(context, client, ccache, uid, gid);
174	    }
175	}
176    }
177
178    *ccache_p = ccache;
179    return 0;
180}
181
182