1/*
2 * Copyright (c) 1997-2001 Kungliga Tekniska Högskolan
3 * (Royal Institute of Technology, Stockholm, Sweden).
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 *
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 *
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 *
17 * 3. Neither the name of the Institute nor the names of its contributors
18 *    may be used to endorse or promote products derived from this software
19 *    without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34#include "krb5_locl.h"
35#include <vis.h>
36
37struct krb5_rcache_data {
38    char *name;
39};
40
41KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
42krb5_rc_resolve(krb5_context context,
43		krb5_rcache id,
44		const char *name)
45{
46    id->name = strdup(name);
47    if(id->name == NULL) {
48	krb5_set_error_message(context, KRB5_RC_MALLOC,
49			       N_("malloc: out of memory", ""));
50	return KRB5_RC_MALLOC;
51    }
52    return 0;
53}
54
55KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
56krb5_rc_resolve_type(krb5_context context,
57		     krb5_rcache *id,
58		     const char *type)
59{
60    *id = NULL;
61    if(strcmp(type, "FILE")) {
62	krb5_set_error_message (context, KRB5_RC_TYPE_NOTFOUND,
63				N_("replay cache type %s not supported", ""),
64				type);
65	return KRB5_RC_TYPE_NOTFOUND;
66    }
67    *id = calloc(1, sizeof(**id));
68    if(*id == NULL) {
69	krb5_set_error_message(context, KRB5_RC_MALLOC,
70			       N_("malloc: out of memory", ""));
71	return KRB5_RC_MALLOC;
72    }
73    return 0;
74}
75
76KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
77krb5_rc_resolve_full(krb5_context context,
78		     krb5_rcache *id,
79		     const char *string_name)
80{
81    krb5_error_code ret;
82
83    *id = NULL;
84
85    if(strncmp(string_name, "FILE:", 5)) {
86	krb5_set_error_message(context, KRB5_RC_TYPE_NOTFOUND,
87			       N_("replay cache type %s not supported", ""),
88			       string_name);
89	return KRB5_RC_TYPE_NOTFOUND;
90    }
91    ret = krb5_rc_resolve_type(context, id, "FILE");
92    if(ret)
93	return ret;
94    ret = krb5_rc_resolve(context, *id, string_name + 5);
95    if (ret) {
96	krb5_rc_close(context, *id);
97	*id = NULL;
98    }
99    return ret;
100}
101
102KRB5_LIB_FUNCTION const char* KRB5_LIB_CALL
103krb5_rc_default_name(krb5_context context)
104{
105    return "FILE:/var/run/default_rcache";
106}
107
108KRB5_LIB_FUNCTION const char* KRB5_LIB_CALL
109krb5_rc_default_type(krb5_context context)
110{
111    return "FILE";
112}
113
114KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
115krb5_rc_default(krb5_context context,
116		krb5_rcache *id)
117{
118    return krb5_rc_resolve_full(context, id, krb5_rc_default_name(context));
119}
120
121struct rc_entry{
122    time_t stamp;
123    unsigned char data[16];
124};
125
126KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
127krb5_rc_initialize(krb5_context context,
128		   krb5_rcache id,
129		   krb5_deltat auth_lifespan)
130{
131    FILE *f = fopen(id->name, "w");
132    struct rc_entry tmp;
133    int ret;
134
135    if(f == NULL) {
136	char buf[128];
137	ret = errno;
138	rk_strerror_r(ret, buf, sizeof(buf));
139	krb5_set_error_message(context, ret, "open(%s): %s", id->name, buf);
140	return ret;
141    }
142    tmp.stamp = auth_lifespan;
143    fwrite(&tmp, 1, sizeof(tmp), f);
144    fclose(f);
145    return 0;
146}
147
148KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
149krb5_rc_recover(krb5_context context,
150		krb5_rcache id)
151{
152    return 0;
153}
154
155KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
156krb5_rc_destroy(krb5_context context,
157		krb5_rcache id)
158{
159    int ret;
160
161    if(remove(id->name) < 0) {
162	char buf[128];
163	ret = errno;
164	rk_strerror_r(ret, buf, sizeof(buf));
165	krb5_set_error_message(context, ret, "remove(%s): %s", id->name, buf);
166	return ret;
167    }
168    return krb5_rc_close(context, id);
169}
170
171KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
172krb5_rc_close(krb5_context context,
173	      krb5_rcache id)
174{
175    free(id->name);
176    free(id);
177    return 0;
178}
179
180static void
181checksum_authenticator(Authenticator *auth, void *data)
182{
183    EVP_MD_CTX *m = EVP_MD_CTX_create();
184    unsigned i;
185
186    EVP_DigestInit_ex(m, EVP_md5(), NULL);
187
188    EVP_DigestUpdate(m, auth->crealm, strlen(auth->crealm));
189    for(i = 0; i < auth->cname.name_string.len; i++)
190	EVP_DigestUpdate(m, auth->cname.name_string.val[i],
191		   strlen(auth->cname.name_string.val[i]));
192    EVP_DigestUpdate(m, &auth->ctime, sizeof(auth->ctime));
193    EVP_DigestUpdate(m, &auth->cusec, sizeof(auth->cusec));
194
195    EVP_DigestFinal_ex(m, data, NULL);
196    EVP_MD_CTX_destroy(m);
197}
198
199KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
200krb5_rc_store(krb5_context context,
201	      krb5_rcache id,
202	      krb5_donot_replay *rep)
203{
204    struct rc_entry ent, tmp;
205    time_t t;
206    FILE *f;
207    int ret;
208
209    ent.stamp = time(NULL);
210    checksum_authenticator(rep, ent.data);
211    f = fopen(id->name, "r");
212    if(f == NULL) {
213	char buf[128];
214	ret = errno;
215	rk_strerror_r(ret, buf, sizeof(buf));
216	krb5_set_error_message(context, ret, "open(%s): %s", id->name, buf);
217	return ret;
218    }
219    rk_cloexec_file(f);
220    fread(&tmp, sizeof(ent), 1, f);
221    t = ent.stamp - tmp.stamp;
222    while(fread(&tmp, sizeof(ent), 1, f)){
223	if(tmp.stamp < t)
224	    continue;
225	if(memcmp(tmp.data, ent.data, sizeof(ent.data)) == 0){
226	    fclose(f);
227	    krb5_clear_error_message (context);
228	    return KRB5_RC_REPLAY;
229	}
230    }
231    if(ferror(f)){
232	char buf[128];
233	ret = errno;
234	fclose(f);
235	rk_strerror_r(ret, buf, sizeof(buf));
236	krb5_set_error_message(context, ret, "%s: %s",
237			       id->name, buf);
238	return ret;
239    }
240    fclose(f);
241    f = fopen(id->name, "a");
242    if(f == NULL) {
243	char buf[128];
244	rk_strerror_r(errno, buf, sizeof(buf));
245	krb5_set_error_message(context, KRB5_RC_IO_UNKNOWN,
246			       "open(%s): %s", id->name, buf);
247	return KRB5_RC_IO_UNKNOWN;
248    }
249    fwrite(&ent, 1, sizeof(ent), f);
250    fclose(f);
251    return 0;
252}
253
254KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
255krb5_rc_expunge(krb5_context context,
256		krb5_rcache id)
257{
258    return 0;
259}
260
261KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
262krb5_rc_get_lifespan(krb5_context context,
263		     krb5_rcache id,
264		     krb5_deltat *auth_lifespan)
265{
266    FILE *f = fopen(id->name, "r");
267    int r;
268    struct rc_entry ent;
269    r = fread(&ent, sizeof(ent), 1, f);
270    fclose(f);
271    if(r){
272	*auth_lifespan = ent.stamp;
273	return 0;
274    }
275    krb5_clear_error_message (context);
276    return KRB5_RC_IO_UNKNOWN;
277}
278
279KRB5_LIB_FUNCTION const char* KRB5_LIB_CALL
280krb5_rc_get_name(krb5_context context,
281		 krb5_rcache id)
282{
283    return id->name;
284}
285
286KRB5_LIB_FUNCTION const char* KRB5_LIB_CALL
287krb5_rc_get_type(krb5_context context,
288		 krb5_rcache id)
289{
290    return "FILE";
291}
292
293KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
294krb5_get_server_rcache(krb5_context context,
295		       const krb5_data *piece,
296		       krb5_rcache *id)
297{
298    krb5_rcache rcache;
299    krb5_error_code ret;
300
301    char *tmp = malloc(4 * piece->length + 1);
302    char *name;
303
304    if(tmp == NULL) {
305	krb5_set_error_message(context, ENOMEM,
306			       N_("malloc: out of memory", ""));
307	return ENOMEM;
308    }
309    strvisx(tmp, piece->data, piece->length, VIS_WHITE | VIS_OCTAL);
310#ifdef HAVE_GETEUID
311    ret = asprintf(&name, "FILE:rc_%s_%u", tmp, (unsigned)geteuid());
312#else
313    ret = asprintf(&name, "FILE:rc_%s", tmp);
314#endif
315    free(tmp);
316    if(ret < 0 || name == NULL) {
317	krb5_set_error_message(context, ENOMEM,
318			       N_("malloc: out of memory", ""));
319	return ENOMEM;
320    }
321
322    ret = krb5_rc_resolve_full(context, &rcache, name);
323    free(name);
324    if(ret)
325	return ret;
326    *id = rcache;
327    return ret;
328}
329