xref: /netbsd-src/crypto/external/bsd/heimdal/dist/lib/krb5/replay.c (revision d3273b5b76f5afaafe308cead5511dbb8df8c5e9)
1 /*	$NetBSD: replay.c,v 1.2 2017/01/28 21:31:49 christos Exp $	*/
2 
3 /*
4  * Copyright (c) 1997-2001 Kungliga Tekniska Högskolan
5  * (Royal Institute of Technology, Stockholm, Sweden).
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  *
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  *
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * 3. Neither the name of the Institute nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #include "krb5_locl.h"
37 #include <vis.h>
38 
39 struct krb5_rcache_data {
40     char *name;
41 };
42 
43 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_rc_resolve(krb5_context context,krb5_rcache id,const char * name)44 krb5_rc_resolve(krb5_context context,
45 		krb5_rcache id,
46 		const char *name)
47 {
48     id->name = strdup(name);
49     if(id->name == NULL) {
50 	krb5_set_error_message(context, KRB5_RC_MALLOC,
51 			       N_("malloc: out of memory", ""));
52 	return KRB5_RC_MALLOC;
53     }
54     return 0;
55 }
56 
57 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_rc_resolve_type(krb5_context context,krb5_rcache * id,const char * type)58 krb5_rc_resolve_type(krb5_context context,
59 		     krb5_rcache *id,
60 		     const char *type)
61 {
62     *id = NULL;
63     if(strcmp(type, "FILE")) {
64 	krb5_set_error_message (context, KRB5_RC_TYPE_NOTFOUND,
65 				N_("replay cache type %s not supported", ""),
66 				type);
67 	return KRB5_RC_TYPE_NOTFOUND;
68     }
69     *id = calloc(1, sizeof(**id));
70     if(*id == NULL) {
71 	krb5_set_error_message(context, KRB5_RC_MALLOC,
72 			       N_("malloc: out of memory", ""));
73 	return KRB5_RC_MALLOC;
74     }
75     return 0;
76 }
77 
78 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_rc_resolve_full(krb5_context context,krb5_rcache * id,const char * string_name)79 krb5_rc_resolve_full(krb5_context context,
80 		     krb5_rcache *id,
81 		     const char *string_name)
82 {
83     krb5_error_code ret;
84 
85     *id = NULL;
86 
87     if(strncmp(string_name, "FILE:", 5)) {
88 	krb5_set_error_message(context, KRB5_RC_TYPE_NOTFOUND,
89 			       N_("replay cache type %s not supported", ""),
90 			       string_name);
91 	return KRB5_RC_TYPE_NOTFOUND;
92     }
93     ret = krb5_rc_resolve_type(context, id, "FILE");
94     if(ret)
95 	return ret;
96     ret = krb5_rc_resolve(context, *id, string_name + 5);
97     if (ret) {
98 	krb5_rc_close(context, *id);
99 	*id = NULL;
100     }
101     return ret;
102 }
103 
104 KRB5_LIB_FUNCTION const char* KRB5_LIB_CALL
krb5_rc_default_name(krb5_context context)105 krb5_rc_default_name(krb5_context context)
106 {
107     return "FILE:/var/run/default_rcache";
108 }
109 
110 KRB5_LIB_FUNCTION const char* KRB5_LIB_CALL
krb5_rc_default_type(krb5_context context)111 krb5_rc_default_type(krb5_context context)
112 {
113     return "FILE";
114 }
115 
116 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_rc_default(krb5_context context,krb5_rcache * id)117 krb5_rc_default(krb5_context context,
118 		krb5_rcache *id)
119 {
120     return krb5_rc_resolve_full(context, id, krb5_rc_default_name(context));
121 }
122 
123 struct rc_entry{
124     time_t stamp;
125     unsigned char data[16];
126 };
127 
128 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_rc_initialize(krb5_context context,krb5_rcache id,krb5_deltat auth_lifespan)129 krb5_rc_initialize(krb5_context context,
130 		   krb5_rcache id,
131 		   krb5_deltat auth_lifespan)
132 {
133     FILE *f = fopen(id->name, "w");
134     struct rc_entry tmp;
135     int ret;
136 
137     if(f == NULL) {
138 	char buf[128];
139 	ret = errno;
140 	rk_strerror_r(ret, buf, sizeof(buf));
141 	krb5_set_error_message(context, ret, "open(%s): %s", id->name, buf);
142 	return ret;
143     }
144     memset(&tmp, 0, sizeof(tmp));
145     tmp.stamp = auth_lifespan;
146     fwrite(&tmp, 1, sizeof(tmp), f);
147     fclose(f);
148     return 0;
149 }
150 
151 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_rc_recover(krb5_context context,krb5_rcache id)152 krb5_rc_recover(krb5_context context,
153 		krb5_rcache id)
154 {
155     return 0;
156 }
157 
158 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_rc_destroy(krb5_context context,krb5_rcache id)159 krb5_rc_destroy(krb5_context context,
160 		krb5_rcache id)
161 {
162     int ret;
163 
164     if(remove(id->name) < 0) {
165 	char buf[128];
166 	ret = errno;
167 	rk_strerror_r(ret, buf, sizeof(buf));
168 	krb5_set_error_message(context, ret, "remove(%s): %s", id->name, buf);
169 	return ret;
170     }
171     return krb5_rc_close(context, id);
172 }
173 
174 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_rc_close(krb5_context context,krb5_rcache id)175 krb5_rc_close(krb5_context context,
176 	      krb5_rcache id)
177 {
178     free(id->name);
179     free(id);
180     return 0;
181 }
182 
183 static void
checksum_authenticator(Authenticator * auth,void * data)184 checksum_authenticator(Authenticator *auth, void *data)
185 {
186     EVP_MD_CTX *m = EVP_MD_CTX_create();
187     unsigned i;
188 
189     EVP_DigestInit_ex(m, EVP_md5(), NULL);
190 
191     EVP_DigestUpdate(m, auth->crealm, strlen(auth->crealm));
192     for(i = 0; i < auth->cname.name_string.len; i++)
193 	EVP_DigestUpdate(m, auth->cname.name_string.val[i],
194 		   strlen(auth->cname.name_string.val[i]));
195     EVP_DigestUpdate(m, &auth->ctime, sizeof(auth->ctime));
196     EVP_DigestUpdate(m, &auth->cusec, sizeof(auth->cusec));
197 
198     EVP_DigestFinal_ex(m, data, NULL);
199     EVP_MD_CTX_destroy(m);
200 }
201 
202 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_rc_store(krb5_context context,krb5_rcache id,krb5_donot_replay * rep)203 krb5_rc_store(krb5_context context,
204 	      krb5_rcache id,
205 	      krb5_donot_replay *rep)
206 {
207     struct rc_entry ent, tmp;
208     time_t t;
209     FILE *f;
210     int ret;
211     size_t count;
212 
213     ent.stamp = time(NULL);
214     checksum_authenticator(rep, ent.data);
215     f = fopen(id->name, "r");
216     if(f == NULL) {
217 	char buf[128];
218 	ret = errno;
219 	rk_strerror_r(ret, buf, sizeof(buf));
220 	krb5_set_error_message(context, ret, "open(%s): %s", id->name, buf);
221 	return ret;
222     }
223     rk_cloexec_file(f);
224     count = fread(&tmp, sizeof(ent), 1, f);
225     if(count != 1)
226 	return KRB5_RC_IO_UNKNOWN;
227     t = ent.stamp - tmp.stamp;
228     while(fread(&tmp, sizeof(ent), 1, f)){
229 	if(tmp.stamp < t)
230 	    continue;
231 	if(memcmp(tmp.data, ent.data, sizeof(ent.data)) == 0){
232 	    fclose(f);
233 	    krb5_clear_error_message (context);
234 	    return KRB5_RC_REPLAY;
235 	}
236     }
237     if(ferror(f)){
238 	char buf[128];
239 	ret = errno;
240 	fclose(f);
241 	rk_strerror_r(ret, buf, sizeof(buf));
242 	krb5_set_error_message(context, ret, "%s: %s",
243 			       id->name, buf);
244 	return ret;
245     }
246     fclose(f);
247     f = fopen(id->name, "a");
248     if(f == NULL) {
249 	char buf[128];
250 	rk_strerror_r(errno, buf, sizeof(buf));
251 	krb5_set_error_message(context, KRB5_RC_IO_UNKNOWN,
252 			       "open(%s): %s", id->name, buf);
253 	return KRB5_RC_IO_UNKNOWN;
254     }
255     fwrite(&ent, 1, sizeof(ent), f);
256     fclose(f);
257     return 0;
258 }
259 
260 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_rc_expunge(krb5_context context,krb5_rcache id)261 krb5_rc_expunge(krb5_context context,
262 		krb5_rcache id)
263 {
264     return 0;
265 }
266 
267 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_rc_get_lifespan(krb5_context context,krb5_rcache id,krb5_deltat * auth_lifespan)268 krb5_rc_get_lifespan(krb5_context context,
269 		     krb5_rcache id,
270 		     krb5_deltat *auth_lifespan)
271 {
272     FILE *f = fopen(id->name, "r");
273     int r;
274     struct rc_entry ent;
275     r = fread(&ent, sizeof(ent), 1, f);
276     fclose(f);
277     if(r){
278 	*auth_lifespan = ent.stamp;
279 	return 0;
280     }
281     krb5_clear_error_message (context);
282     return KRB5_RC_IO_UNKNOWN;
283 }
284 
285 KRB5_LIB_FUNCTION const char* KRB5_LIB_CALL
krb5_rc_get_name(krb5_context context,krb5_rcache id)286 krb5_rc_get_name(krb5_context context,
287 		 krb5_rcache id)
288 {
289     return id->name;
290 }
291 
292 KRB5_LIB_FUNCTION const char* KRB5_LIB_CALL
krb5_rc_get_type(krb5_context context,krb5_rcache id)293 krb5_rc_get_type(krb5_context context,
294 		 krb5_rcache id)
295 {
296     return "FILE";
297 }
298 
299 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_get_server_rcache(krb5_context context,const krb5_data * piece,krb5_rcache * id)300 krb5_get_server_rcache(krb5_context context,
301 		       const krb5_data *piece,
302 		       krb5_rcache *id)
303 {
304     krb5_rcache rcache;
305     krb5_error_code ret;
306 
307     char *tmp = malloc(4 * piece->length + 1);
308     char *name;
309 
310     if (tmp == NULL)
311 	return krb5_enomem(context);
312     strvisx(tmp, piece->data, piece->length, VIS_WHITE | VIS_OCTAL);
313 #ifdef HAVE_GETEUID
314     ret = asprintf(&name, "FILE:rc_%s_%u", tmp, (unsigned)geteuid());
315 #else
316     ret = asprintf(&name, "FILE:rc_%s", tmp);
317 #endif
318     free(tmp);
319     if (ret < 0 || name == NULL)
320 	return krb5_enomem(context);
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