1/*
2 * Copyright (c) 2005, PADL Software Pty Ltd.
3 * All rights reserved.
4 *
5 * Portions Copyright (c) 2009 Apple Inc. 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#include <pwd.h>
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    kcm_cleanup_events(context, ccache);
80    kcm_release_ccache(context, ccache);
81    if (ret)
82	return ret;
83
84    return kcm_ccache_destroy(context, name);
85}
86
87krb5_error_code
88kcm_ccache_new_client(krb5_context context,
89		      kcm_client *client,
90		      const char *name,
91		      kcm_ccache *ccache_p)
92{
93    krb5_error_code ret;
94    kcm_ccache ccache;
95
96    /* We insist the ccache name starts with UID or UID: */
97    if (name_constraints != 0) {
98	char prefix[64];
99	size_t prefix_len;
100	int bad = 1;
101
102	snprintf(prefix, sizeof(prefix), "%ld:", (long)client->uid);
103	prefix_len = strlen(prefix);
104
105	if (strncmp(name, prefix, prefix_len) == 0)
106	    bad = 0;
107	else {
108	    prefix[prefix_len - 1] = '\0';
109	    if (strcmp(name, prefix) == 0)
110		bad = 0;
111	}
112
113	/* Allow root to create badly-named ccaches */
114	if (bad && !CLIENT_IS_ROOT(client))
115	    return KRB5_CC_BADNAME;
116    }
117
118    ret = kcm_ccache_resolve(context, name, &ccache);
119    if (ret == 0) {
120	if ((ccache->uid != client->uid ||
121	     ccache->gid != client->gid) && !CLIENT_IS_ROOT(client))
122	    return KRB5_FCC_PERM;
123    } else if (ret != KRB5_FCC_NOFILE && !(CLIENT_IS_ROOT(client) && ret == KRB5_FCC_PERM)) {
124		return ret;
125    }
126
127    if (ret == KRB5_FCC_NOFILE) {
128	ret = kcm_ccache_new(context, name, &ccache);
129	if (ret) {
130	    kcm_log(1, "Failed to initialize cache %s: %s",
131		    name, krb5_get_err_text(context, ret));
132	    return ret;
133	}
134
135	/* bind to current client */
136	ccache->uid = client->uid;
137	ccache->gid = client->gid;
138	ccache->session = client->session;
139    } else {
140	ret = kcm_zero_ccache_data(context, ccache);
141	if (ret) {
142	    kcm_log(1, "Failed to empty cache %s: %s",
143		    name, krb5_get_err_text(context, ret));
144	    kcm_release_ccache(context, ccache);
145	    return ret;
146	}
147	kcm_cleanup_events(context, ccache);
148    }
149
150    ret = kcm_access(context, client, KCM_OP_INITIALIZE, ccache);
151    if (ret) {
152	kcm_release_ccache(context, ccache);
153	kcm_ccache_destroy(context, name);
154	return ret;
155    }
156
157    /*
158     * Finally, if the user is root and the cache was created under
159     * another user's name, chown the cache to that user and their
160     * default gid.
161     */
162    if (CLIENT_IS_ROOT(client)) {
163	unsigned long uid;
164	int matches = sscanf(name,"%ld:",&uid);
165	if (matches == 0)
166	    matches = sscanf(name,"%ld",&uid);
167	if (matches == 1) {
168	    struct passwd *pwd = getpwuid(uid);
169	    if (pwd != NULL) {
170		gid_t gid = pwd->pw_gid;
171		kcm_chown(context, client, ccache, uid, gid);
172	    }
173	}
174    }
175
176    *ccache_p = ccache;
177    return 0;
178}
179
180