1 /* 2 * Copyright (c) 1997 - 2001 Kungliga Tekniska H�gskolan 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 36 RCSID("$Id: keytab.c,v 1.50 2001/05/14 06:14:48 assar Exp $"); 37 38 /* 39 * Register a new keytab in `ops' 40 * Return 0 or an error. 41 */ 42 43 krb5_error_code 44 krb5_kt_register(krb5_context context, 45 const krb5_kt_ops *ops) 46 { 47 struct krb5_keytab_data *tmp; 48 49 tmp = realloc(context->kt_types, 50 (context->num_kt_types + 1) * sizeof(*context->kt_types)); 51 if(tmp == NULL) { 52 krb5_set_error_string(context, "malloc: out of memory"); 53 return ENOMEM; 54 } 55 memcpy(&tmp[context->num_kt_types], ops, 56 sizeof(tmp[context->num_kt_types])); 57 context->kt_types = tmp; 58 context->num_kt_types++; 59 return 0; 60 } 61 62 /* 63 * Resolve the keytab name (of the form `type:residual') in `name' 64 * into a keytab in `id'. 65 * Return 0 or an error 66 */ 67 68 krb5_error_code 69 krb5_kt_resolve(krb5_context context, 70 const char *name, 71 krb5_keytab *id) 72 { 73 krb5_keytab k; 74 int i; 75 const char *type, *residual; 76 size_t type_len; 77 krb5_error_code ret; 78 79 residual = strchr(name, ':'); 80 if(residual == NULL) { 81 type = "FILE"; 82 type_len = strlen(type); 83 residual = name; 84 } else { 85 type = name; 86 type_len = residual - name; 87 residual++; 88 } 89 90 for(i = 0; i < context->num_kt_types; i++) { 91 if(strncmp(type, context->kt_types[i].prefix, type_len) == 0) 92 break; 93 } 94 if(i == context->num_kt_types) { 95 krb5_set_error_string(context, "unknown keytab type %.*s", 96 (int)type_len, type); 97 return KRB5_KT_UNKNOWN_TYPE; 98 } 99 100 k = malloc (sizeof(*k)); 101 if (k == NULL) { 102 krb5_set_error_string(context, "malloc: out of memory"); 103 return ENOMEM; 104 } 105 memcpy(k, &context->kt_types[i], sizeof(*k)); 106 k->data = NULL; 107 ret = (*k->resolve)(context, residual, k); 108 if(ret) { 109 free(k); 110 k = NULL; 111 } 112 *id = k; 113 return ret; 114 } 115 116 /* 117 * copy the name of the default keytab into `name'. 118 * Return 0 or KRB5_CONFIG_NOTENUFSPACE if `namesize' is too short. 119 */ 120 121 krb5_error_code 122 krb5_kt_default_name(krb5_context context, char *name, size_t namesize) 123 { 124 if (strlcpy (name, context->default_keytab, namesize) >= namesize) { 125 krb5_clear_error_string (context); 126 return KRB5_CONFIG_NOTENUFSPACE; 127 } 128 return 0; 129 } 130 131 /* 132 * copy the name of the default modify keytab into `name'. 133 * Return 0 or KRB5_CONFIG_NOTENUFSPACE if `namesize' is too short. 134 */ 135 136 krb5_error_code 137 krb5_kt_default_modify_name(krb5_context context, char *name, size_t namesize) 138 { 139 if (strlcpy (name, context->default_keytab_modify, namesize) >= namesize) { 140 krb5_clear_error_string (context); 141 return KRB5_CONFIG_NOTENUFSPACE; 142 } 143 return 0; 144 } 145 146 /* 147 * Set `id' to the default keytab. 148 * Return 0 or an error. 149 */ 150 151 krb5_error_code 152 krb5_kt_default(krb5_context context, krb5_keytab *id) 153 { 154 return krb5_kt_resolve (context, context->default_keytab, id); 155 } 156 157 /* 158 * Read the key identified by `(principal, vno, enctype)' from the 159 * keytab in `keyprocarg' (the default if == NULL) into `*key'. 160 * Return 0 or an error. 161 */ 162 163 krb5_error_code 164 krb5_kt_read_service_key(krb5_context context, 165 krb5_pointer keyprocarg, 166 krb5_principal principal, 167 krb5_kvno vno, 168 krb5_enctype enctype, 169 krb5_keyblock **key) 170 { 171 krb5_keytab keytab; 172 krb5_keytab_entry entry; 173 krb5_error_code ret; 174 175 if (keyprocarg) 176 ret = krb5_kt_resolve (context, keyprocarg, &keytab); 177 else 178 ret = krb5_kt_default (context, &keytab); 179 180 if (ret) 181 return ret; 182 183 ret = krb5_kt_get_entry (context, keytab, principal, vno, enctype, &entry); 184 krb5_kt_close (context, keytab); 185 if (ret) 186 return ret; 187 ret = krb5_copy_keyblock (context, &entry.keyblock, key); 188 krb5_kt_free_entry(context, &entry); 189 return ret; 190 } 191 192 /* 193 * Retrieve the name of the keytab `keytab' into `name', `namesize' 194 * Return 0 or an error. 195 */ 196 197 krb5_error_code 198 krb5_kt_get_name(krb5_context context, 199 krb5_keytab keytab, 200 char *name, 201 size_t namesize) 202 { 203 return (*keytab->get_name)(context, keytab, name, namesize); 204 } 205 206 /* 207 * Finish using the keytab in `id'. All resources will be released. 208 * Return 0 or an error. 209 */ 210 211 krb5_error_code 212 krb5_kt_close(krb5_context context, 213 krb5_keytab id) 214 { 215 krb5_error_code ret; 216 217 ret = (*id->close)(context, id); 218 if(ret == 0) 219 free(id); 220 return ret; 221 } 222 223 /* 224 * Compare `entry' against `principal, vno, enctype'. 225 * Any of `principal, vno, enctype' might be 0 which acts as a wildcard. 226 * Return TRUE if they compare the same, FALSE otherwise. 227 */ 228 229 krb5_boolean 230 krb5_kt_compare(krb5_context context, 231 krb5_keytab_entry *entry, 232 krb5_const_principal principal, 233 krb5_kvno vno, 234 krb5_enctype enctype) 235 { 236 if(principal != NULL && 237 !krb5_principal_compare(context, entry->principal, principal)) 238 return FALSE; 239 if(vno && vno != entry->vno) 240 return FALSE; 241 if(enctype && enctype != entry->keyblock.keytype) 242 return FALSE; 243 return TRUE; 244 } 245 246 /* 247 * Retrieve the keytab entry for `principal, kvno, enctype' into `entry' 248 * from the keytab `id'. 249 * Return 0 or an error. 250 */ 251 252 krb5_error_code 253 krb5_kt_get_entry(krb5_context context, 254 krb5_keytab id, 255 krb5_const_principal principal, 256 krb5_kvno kvno, 257 krb5_enctype enctype, 258 krb5_keytab_entry *entry) 259 { 260 krb5_keytab_entry tmp; 261 krb5_error_code ret; 262 krb5_kt_cursor cursor; 263 264 if(id->get) 265 return (*id->get)(context, id, principal, kvno, enctype, entry); 266 267 ret = krb5_kt_start_seq_get (context, id, &cursor); 268 if (ret) 269 return KRB5_KT_NOTFOUND; /* XXX i.e. file not found */ 270 271 entry->vno = 0; 272 while (krb5_kt_next_entry(context, id, &tmp, &cursor) == 0) { 273 if (krb5_kt_compare(context, &tmp, principal, 0, enctype)) { 274 if (kvno == tmp.vno) { 275 krb5_kt_copy_entry_contents (context, &tmp, entry); 276 krb5_kt_free_entry (context, &tmp); 277 krb5_kt_end_seq_get(context, id, &cursor); 278 return 0; 279 } else if (kvno == 0 && tmp.vno > entry->vno) { 280 if (entry->vno) 281 krb5_kt_free_entry (context, entry); 282 krb5_kt_copy_entry_contents (context, &tmp, entry); 283 } 284 } 285 krb5_kt_free_entry(context, &tmp); 286 } 287 krb5_kt_end_seq_get (context, id, &cursor); 288 if (entry->vno) { 289 return 0; 290 } else { 291 char princ[256], kt_name[256]; 292 293 krb5_unparse_name_fixed (context, principal, princ, sizeof(princ)); 294 krb5_kt_get_name (context, id, kt_name, sizeof(kt_name)); 295 296 krb5_set_error_string (context, 297 "failed to find %s in keytab %s", 298 princ, kt_name); 299 return KRB5_KT_NOTFOUND; 300 } 301 } 302 303 /* 304 * Copy the contents of `in' into `out'. 305 * Return 0 or an error. 306 */ 307 308 krb5_error_code 309 krb5_kt_copy_entry_contents(krb5_context context, 310 const krb5_keytab_entry *in, 311 krb5_keytab_entry *out) 312 { 313 krb5_error_code ret; 314 315 memset(out, 0, sizeof(*out)); 316 out->vno = in->vno; 317 318 ret = krb5_copy_principal (context, in->principal, &out->principal); 319 if (ret) 320 goto fail; 321 ret = krb5_copy_keyblock_contents (context, 322 &in->keyblock, 323 &out->keyblock); 324 if (ret) 325 goto fail; 326 out->timestamp = in->timestamp; 327 return 0; 328 fail: 329 krb5_kt_free_entry (context, out); 330 return ret; 331 } 332 333 /* 334 * Free the contents of `entry'. 335 */ 336 337 krb5_error_code 338 krb5_kt_free_entry(krb5_context context, 339 krb5_keytab_entry *entry) 340 { 341 krb5_free_principal (context, entry->principal); 342 krb5_free_keyblock_contents (context, &entry->keyblock); 343 return 0; 344 } 345 346 #if 0 347 static int 348 xxxlock(int fd, int write) 349 { 350 if(flock(fd, (write ? LOCK_EX : LOCK_SH) | LOCK_NB) < 0) { 351 sleep(1); 352 if(flock(fd, (write ? LOCK_EX : LOCK_SH) | LOCK_NB) < 0) 353 return -1; 354 } 355 return 0; 356 } 357 358 static void 359 xxxunlock(int fd) 360 { 361 flock(fd, LOCK_UN); 362 } 363 #endif 364 365 /* 366 * Set `cursor' to point at the beginning of `id'. 367 * Return 0 or an error. 368 */ 369 370 krb5_error_code 371 krb5_kt_start_seq_get(krb5_context context, 372 krb5_keytab id, 373 krb5_kt_cursor *cursor) 374 { 375 if(id->start_seq_get == NULL) { 376 krb5_set_error_string(context, 377 "start_seq_get is not supported in the %s " 378 " keytab", id->prefix); 379 return HEIM_ERR_OPNOTSUPP; 380 } 381 return (*id->start_seq_get)(context, id, cursor); 382 } 383 384 /* 385 * Get the next entry from `id' pointed to by `cursor' and advance the 386 * `cursor'. 387 * Return 0 or an error. 388 */ 389 390 krb5_error_code 391 krb5_kt_next_entry(krb5_context context, 392 krb5_keytab id, 393 krb5_keytab_entry *entry, 394 krb5_kt_cursor *cursor) 395 { 396 if(id->next_entry == NULL) { 397 krb5_set_error_string(context, 398 "next_entry is not supported in the %s " 399 " keytab", id->prefix); 400 return HEIM_ERR_OPNOTSUPP; 401 } 402 return (*id->next_entry)(context, id, entry, cursor); 403 } 404 405 /* 406 * Release all resources associated with `cursor'. 407 */ 408 409 krb5_error_code 410 krb5_kt_end_seq_get(krb5_context context, 411 krb5_keytab id, 412 krb5_kt_cursor *cursor) 413 { 414 if(id->end_seq_get == NULL) { 415 krb5_set_error_string(context, 416 "end_seq_get is not supported in the %s " 417 " keytab", id->prefix); 418 return HEIM_ERR_OPNOTSUPP; 419 } 420 return (*id->end_seq_get)(context, id, cursor); 421 } 422 423 /* 424 * Add the entry in `entry' to the keytab `id'. 425 * Return 0 or an error. 426 */ 427 428 krb5_error_code 429 krb5_kt_add_entry(krb5_context context, 430 krb5_keytab id, 431 krb5_keytab_entry *entry) 432 { 433 if(id->add == NULL) { 434 krb5_set_error_string(context, "Add is not supported in the %s keytab", 435 id->prefix); 436 return KRB5_KT_NOWRITE; 437 } 438 entry->timestamp = time(NULL); 439 return (*id->add)(context, id,entry); 440 } 441 442 /* 443 * Remove the entry `entry' from the keytab `id'. 444 * Return 0 or an error. 445 */ 446 447 krb5_error_code 448 krb5_kt_remove_entry(krb5_context context, 449 krb5_keytab id, 450 krb5_keytab_entry *entry) 451 { 452 if(id->remove == NULL) { 453 krb5_set_error_string(context, 454 "Remove is not supported in the %s keytab", 455 id->prefix); 456 return KRB5_KT_NOWRITE; 457 } 458 return (*id->remove)(context, id, entry); 459 } 460