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DEFINITIONS
This source file includes following definitions.
- hdb_free_keys
- parse_key_set
- add_enctype_to_key_set
- hdb_generate_key_set
- hdb_generate_key_set_password
1 /*
2 * Copyright (c) 1997 - 2001, 2003 - 2004 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 "hdb_locl.h"
35
36 RCSID("$Id$");
37
38 /*
39 * free all the memory used by (len, keys)
40 */
41
42 void
43 hdb_free_keys (krb5_context context, int len, Key *keys)
/* [<][>][^][v][top][bottom][index][help] */
44 {
45 int i;
46
47 for (i = 0; i < len; i++) {
48 free(keys[i].mkvno);
49 keys[i].mkvno = NULL;
50 if (keys[i].salt != NULL) {
51 free_Salt(keys[i].salt);
52 free(keys[i].salt);
53 keys[i].salt = NULL;
54 }
55 krb5_free_keyblock_contents(context, &keys[i].key);
56 }
57 free (keys);
58 }
59
60 /*
61 * for each entry in `default_keys' try to parse it as a sequence
62 * of etype:salttype:salt, syntax of this if something like:
63 * [(des|des3|etype):](pw-salt|afs3)[:string], if etype is omitted it
64 * means all etypes, and if string is omitted is means the default
65 * string (for that principal). Additional special values:
66 * v5 == pw-salt, and
67 * v4 == des:pw-salt:
68 * afs or afs3 == des:afs3-salt
69 */
70
71 static const krb5_enctype des_etypes[] = {
72 ETYPE_DES_CBC_MD5,
73 ETYPE_DES_CBC_MD4,
74 ETYPE_DES_CBC_CRC
75 };
76
77 static const krb5_enctype all_etypes[] = {
78 ETYPE_AES256_CTS_HMAC_SHA1_96,
79 ETYPE_ARCFOUR_HMAC_MD5,
80 ETYPE_DES3_CBC_SHA1
81 };
82
83 static krb5_error_code
84 parse_key_set(krb5_context context, const char *key,
/* [<][>][^][v][top][bottom][index][help] */
85 krb5_enctype **ret_enctypes, size_t *ret_num_enctypes,
86 krb5_salt *salt, krb5_principal principal)
87 {
88 const char *p;
89 char buf[3][256];
90 int num_buf = 0;
91 int i, num_enctypes = 0;
92 krb5_enctype e;
93 const krb5_enctype *enctypes = NULL;
94 krb5_error_code ret;
95
96 p = key;
97
98 *ret_enctypes = NULL;
99 *ret_num_enctypes = 0;
100
101 /* split p in a list of :-separated strings */
102 for(num_buf = 0; num_buf < 3; num_buf++)
103 if(strsep_copy(&p, ":", buf[num_buf], sizeof(buf[num_buf])) == -1)
104 break;
105
106 salt->saltvalue.data = NULL;
107 salt->saltvalue.length = 0;
108
109 for(i = 0; i < num_buf; i++) {
110 if(enctypes == NULL && num_buf > 1) {
111 /* this might be a etype specifier */
112 /* XXX there should be a string_to_etypes handling
113 special cases like `des' and `all' */
114 if(strcmp(buf[i], "des") == 0) {
115 enctypes = des_etypes;
116 num_enctypes = sizeof(des_etypes)/sizeof(des_etypes[0]);
117 } else if(strcmp(buf[i], "des3") == 0) {
118 e = ETYPE_DES3_CBC_SHA1;
119 enctypes = &e;
120 num_enctypes = 1;
121 } else {
122 ret = krb5_string_to_enctype(context, buf[i], &e);
123 if (ret == 0) {
124 enctypes = &e;
125 num_enctypes = 1;
126 } else
127 return ret;
128 }
129 continue;
130 }
131 if(salt->salttype == 0) {
132 /* interpret string as a salt specifier, if no etype
133 is set, this sets default values */
134 /* XXX should perhaps use string_to_salttype, but that
135 interface sucks */
136 if(strcmp(buf[i], "pw-salt") == 0) {
137 if(enctypes == NULL) {
138 enctypes = all_etypes;
139 num_enctypes = sizeof(all_etypes)/sizeof(all_etypes[0]);
140 }
141 salt->salttype = KRB5_PW_SALT;
142 } else if(strcmp(buf[i], "afs3-salt") == 0) {
143 if(enctypes == NULL) {
144 enctypes = des_etypes;
145 num_enctypes = sizeof(des_etypes)/sizeof(des_etypes[0]);
146 }
147 salt->salttype = KRB5_AFS3_SALT;
148 }
149 continue;
150 }
151
152 {
153 /* if there is a final string, use it as the string to
154 salt with, this is mostly useful with null salt for
155 v4 compat, and a cell name for afs compat */
156 salt->saltvalue.data = strdup(buf[i]);
157 if (salt->saltvalue.data == NULL) {
158 krb5_set_error_message(context, ENOMEM, "malloc: out of memory");
159 return ENOMEM;
160 }
161 salt->saltvalue.length = strlen(buf[i]);
162 }
163 }
164
165 if(enctypes == NULL || salt->salttype == 0) {
166 krb5_set_error_message(context, EINVAL, "bad value for default_keys `%s'", key);
167 return EINVAL;
168 }
169
170 /* if no salt was specified make up default salt */
171 if(salt->saltvalue.data == NULL) {
172 if(salt->salttype == KRB5_PW_SALT)
173 ret = krb5_get_pw_salt(context, principal, salt);
174 else if(salt->salttype == KRB5_AFS3_SALT) {
175 krb5_realm *realm = krb5_princ_realm(context, principal);
176 salt->saltvalue.data = strdup(*realm);
177 if(salt->saltvalue.data == NULL) {
178 krb5_set_error_message(context, ENOMEM,
179 "out of memory while "
180 "parsing salt specifiers");
181 return ENOMEM;
182 }
183 strlwr(salt->saltvalue.data);
184 salt->saltvalue.length = strlen(*realm);
185 }
186 }
187
188 *ret_enctypes = malloc(sizeof(enctypes[0]) * num_enctypes);
189 if (*ret_enctypes == NULL) {
190 krb5_free_salt(context, *salt);
191 krb5_set_error_message(context, ENOMEM, "malloc: out of memory");
192 return ENOMEM;
193 }
194 memcpy(*ret_enctypes, enctypes, sizeof(enctypes[0]) * num_enctypes);
195 *ret_num_enctypes = num_enctypes;
196
197 return 0;
198 }
199
200 static krb5_error_code
201 add_enctype_to_key_set(Key **key_set, size_t *nkeyset,
/* [<][>][^][v][top][bottom][index][help] */
202 krb5_enctype enctype, krb5_salt *salt)
203 {
204 krb5_error_code ret;
205 Key key, *tmp;
206
207 memset(&key, 0, sizeof(key));
208
209 tmp = realloc(*key_set, (*nkeyset + 1) * sizeof((*key_set)[0]));
210 if (tmp == NULL)
211 return ENOMEM;
212
213 *key_set = tmp;
214
215 key.key.keytype = enctype;
216 key.key.keyvalue.length = 0;
217 key.key.keyvalue.data = NULL;
218
219 if (salt) {
220 key.salt = malloc(sizeof(*key.salt));
221 if (key.salt == NULL) {
222 free_Key(&key);
223 return ENOMEM;
224 }
225
226 key.salt->type = salt->salttype;
227 krb5_data_zero (&key.salt->salt);
228
229 ret = krb5_data_copy(&key.salt->salt,
230 salt->saltvalue.data,
231 salt->saltvalue.length);
232 if (ret) {
233 free_Key(&key);
234 return ret;
235 }
236 } else
237 key.salt = NULL;
238
239 (*key_set)[*nkeyset] = key;
240
241 *nkeyset += 1;
242
243 return 0;
244 }
245
246
247 /*
248 * Generate the `key_set' from the [kadmin]default_keys statement. If
249 * `no_salt' is set, salt is not important (and will not be set) since
250 * it's random keys that is going to be created.
251 */
252
253 krb5_error_code
254 hdb_generate_key_set(krb5_context context, krb5_principal principal,
/* [<][>][^][v][top][bottom][index][help] */
255 Key **ret_key_set, size_t *nkeyset, int no_salt)
256 {
257 char **ktypes, **kp;
258 krb5_error_code ret;
259 Key *k, *key_set;
260 int i, j;
261 char *default_keytypes[] = {
262 "des:pw-salt",
263 "aes256-cts-hmac-sha1-96:pw-salt",
264 "des3-cbc-sha1:pw-salt",
265 "arcfour-hmac-md5:pw-salt",
266 NULL
267 };
268
269 ktypes = krb5_config_get_strings(context, NULL, "kadmin",
270 "default_keys", NULL);
271 if (ktypes == NULL)
272 ktypes = default_keytypes;
273
274 if (ktypes == NULL)
275 abort();
276
277 *ret_key_set = key_set = NULL;
278 *nkeyset = 0;
279
280 ret = 0;
281
282 for(kp = ktypes; kp && *kp; kp++) {
283 const char *p;
284 krb5_salt salt;
285 krb5_enctype *enctypes;
286 size_t num_enctypes;
287
288 p = *kp;
289 /* check alias */
290 if(strcmp(p, "v5") == 0)
291 p = "pw-salt";
292 else if(strcmp(p, "v4") == 0)
293 p = "des:pw-salt:";
294 else if(strcmp(p, "afs") == 0 || strcmp(p, "afs3") == 0)
295 p = "des:afs3-salt";
296 else if (strcmp(p, "arcfour-hmac-md5") == 0)
297 p = "arcfour-hmac-md5:pw-salt";
298
299 memset(&salt, 0, sizeof(salt));
300
301 ret = parse_key_set(context, p,
302 &enctypes, &num_enctypes, &salt, principal);
303 if (ret) {
304 krb5_warn(context, ret, "bad value for default_keys `%s'", *kp);
305 ret = 0;
306 continue;
307 }
308
309 for (i = 0; i < num_enctypes; i++) {
310 /* find duplicates */
311 for (j = 0; j < *nkeyset; j++) {
312
313 k = &key_set[j];
314
315 if (k->key.keytype == enctypes[i]) {
316 if (no_salt)
317 break;
318 if (k->salt == NULL && salt.salttype == KRB5_PW_SALT)
319 break;
320 if (k->salt->type == salt.salttype &&
321 k->salt->salt.length == salt.saltvalue.length &&
322 memcmp(k->salt->salt.data, salt.saltvalue.data,
323 salt.saltvalue.length) == 0)
324 break;
325 }
326 }
327 /* not a duplicate, lets add it */
328 if (j == *nkeyset) {
329 ret = add_enctype_to_key_set(&key_set, nkeyset, enctypes[i],
330 no_salt ? NULL : &salt);
331 if (ret) {
332 free(enctypes);
333 krb5_free_salt(context, salt);
334 goto out;
335 }
336 }
337 }
338 free(enctypes);
339 krb5_free_salt(context, salt);
340 }
341
342 *ret_key_set = key_set;
343
344 out:
345 if (ktypes != default_keytypes)
346 krb5_config_free_strings(ktypes);
347
348 if (ret) {
349 krb5_warn(context, ret,
350 "failed to parse the [kadmin]default_keys values");
351
352 for (i = 0; i < *nkeyset; i++)
353 free_Key(&key_set[i]);
354 free(key_set);
355 } else if (*nkeyset == 0) {
356 krb5_warnx(context,
357 "failed to parse any of the [kadmin]default_keys values");
358 ret = EINVAL; /* XXX */
359 }
360
361 return ret;
362 }
363
364
365 krb5_error_code
366 hdb_generate_key_set_password(krb5_context context,
/* [<][>][^][v][top][bottom][index][help] */
367 krb5_principal principal,
368 const char *password,
369 Key **keys, size_t *num_keys)
370 {
371 krb5_error_code ret;
372 int i;
373
374 ret = hdb_generate_key_set(context, principal,
375 keys, num_keys, 0);
376 if (ret)
377 return ret;
378
379 for (i = 0; i < (*num_keys); i++) {
380 krb5_salt salt;
381
382 salt.salttype = (*keys)[i].salt->type;
383 salt.saltvalue.length = (*keys)[i].salt->salt.length;
384 salt.saltvalue.data = (*keys)[i].salt->salt.data;
385
386 ret = krb5_string_to_key_salt (context,
387 (*keys)[i].key.keytype,
388 password,
389 salt,
390 &(*keys)[i].key);
391
392 if(ret)
393 break;
394 }
395
396 if(ret) {
397 hdb_free_keys (context, *num_keys, *keys);
398 return ret;
399 }
400 return ret;
401 }