Daniel P. Berrange | ac1d887 | 2015-10-14 09:58:38 +0100 | [diff] [blame] | 1 | /* |
| 2 | * QEMU crypto secret support |
| 3 | * |
| 4 | * Copyright (c) 2015 Red Hat, Inc. |
| 5 | * |
| 6 | * This library is free software; you can redistribute it and/or |
| 7 | * modify it under the terms of the GNU Lesser General Public |
| 8 | * License as published by the Free Software Foundation; either |
| 9 | * version 2 of the License, or (at your option) any later version. |
| 10 | * |
| 11 | * This library is distributed in the hope that it will be useful, |
| 12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 14 | * Lesser General Public License for more details. |
| 15 | * |
| 16 | * You should have received a copy of the GNU Lesser General Public |
| 17 | * License along with this library; if not, see <http://www.gnu.org/licenses/>. |
| 18 | * |
| 19 | */ |
| 20 | |
Peter Maydell | 42f7a44 | 2016-01-26 18:16:55 +0000 | [diff] [blame] | 21 | #include "qemu/osdep.h" |
Daniel P. Berrange | ac1d887 | 2015-10-14 09:58:38 +0100 | [diff] [blame] | 22 | #include "crypto/secret.h" |
| 23 | #include "crypto/cipher.h" |
Markus Armbruster | da34e65 | 2016-03-14 09:01:28 +0100 | [diff] [blame] | 24 | #include "qapi/error.h" |
Daniel P. Berrange | ac1d887 | 2015-10-14 09:58:38 +0100 | [diff] [blame] | 25 | #include "qom/object_interfaces.h" |
| 26 | #include "qemu/base64.h" |
| 27 | #include "trace.h" |
| 28 | |
| 29 | |
| 30 | static void |
| 31 | qcrypto_secret_load_data(QCryptoSecret *secret, |
| 32 | uint8_t **output, |
| 33 | size_t *outputlen, |
| 34 | Error **errp) |
| 35 | { |
| 36 | char *data = NULL; |
| 37 | size_t length = 0; |
| 38 | GError *gerr = NULL; |
| 39 | |
| 40 | *output = NULL; |
| 41 | *outputlen = 0; |
| 42 | |
| 43 | if (secret->file) { |
| 44 | if (secret->data) { |
| 45 | error_setg(errp, |
| 46 | "'file' and 'data' are mutually exclusive"); |
| 47 | return; |
| 48 | } |
| 49 | if (!g_file_get_contents(secret->file, &data, &length, &gerr)) { |
| 50 | error_setg(errp, |
| 51 | "Unable to read %s: %s", |
| 52 | secret->file, gerr->message); |
| 53 | g_error_free(gerr); |
| 54 | return; |
| 55 | } |
| 56 | *output = (uint8_t *)data; |
| 57 | *outputlen = length; |
| 58 | } else if (secret->data) { |
| 59 | *outputlen = strlen(secret->data); |
| 60 | *output = (uint8_t *)g_strdup(secret->data); |
| 61 | } else { |
| 62 | error_setg(errp, "Either 'file' or 'data' must be provided"); |
| 63 | } |
| 64 | } |
| 65 | |
| 66 | |
| 67 | static void qcrypto_secret_decrypt(QCryptoSecret *secret, |
| 68 | const uint8_t *input, |
| 69 | size_t inputlen, |
| 70 | uint8_t **output, |
| 71 | size_t *outputlen, |
| 72 | Error **errp) |
| 73 | { |
| 74 | uint8_t *key = NULL, *ciphertext = NULL, *iv = NULL; |
| 75 | size_t keylen, ciphertextlen, ivlen; |
| 76 | QCryptoCipher *aes = NULL; |
| 77 | uint8_t *plaintext = NULL; |
| 78 | |
| 79 | *output = NULL; |
| 80 | *outputlen = 0; |
| 81 | |
| 82 | if (qcrypto_secret_lookup(secret->keyid, |
| 83 | &key, &keylen, |
| 84 | errp) < 0) { |
| 85 | goto cleanup; |
| 86 | } |
| 87 | |
| 88 | if (keylen != 32) { |
| 89 | error_setg(errp, "Key should be 32 bytes in length"); |
| 90 | goto cleanup; |
| 91 | } |
| 92 | |
| 93 | if (!secret->iv) { |
| 94 | error_setg(errp, "IV is required to decrypt secret"); |
| 95 | goto cleanup; |
| 96 | } |
| 97 | |
| 98 | iv = qbase64_decode(secret->iv, -1, &ivlen, errp); |
| 99 | if (!iv) { |
| 100 | goto cleanup; |
| 101 | } |
| 102 | if (ivlen != 16) { |
| 103 | error_setg(errp, "IV should be 16 bytes in length not %zu", |
| 104 | ivlen); |
| 105 | goto cleanup; |
| 106 | } |
| 107 | |
| 108 | aes = qcrypto_cipher_new(QCRYPTO_CIPHER_ALG_AES_256, |
| 109 | QCRYPTO_CIPHER_MODE_CBC, |
| 110 | key, keylen, |
| 111 | errp); |
| 112 | if (!aes) { |
| 113 | goto cleanup; |
| 114 | } |
| 115 | |
| 116 | if (qcrypto_cipher_setiv(aes, iv, ivlen, errp) < 0) { |
| 117 | goto cleanup; |
| 118 | } |
| 119 | |
| 120 | if (secret->format == QCRYPTO_SECRET_FORMAT_BASE64) { |
| 121 | ciphertext = qbase64_decode((const gchar*)input, |
| 122 | inputlen, |
| 123 | &ciphertextlen, |
| 124 | errp); |
| 125 | if (!ciphertext) { |
| 126 | goto cleanup; |
| 127 | } |
| 128 | plaintext = g_new0(uint8_t, ciphertextlen + 1); |
| 129 | } else { |
| 130 | ciphertextlen = inputlen; |
| 131 | plaintext = g_new0(uint8_t, inputlen + 1); |
| 132 | } |
| 133 | if (qcrypto_cipher_decrypt(aes, |
| 134 | ciphertext ? ciphertext : input, |
| 135 | plaintext, |
| 136 | ciphertextlen, |
| 137 | errp) < 0) { |
| 138 | plaintext = NULL; |
| 139 | goto cleanup; |
| 140 | } |
| 141 | |
| 142 | if (plaintext[ciphertextlen - 1] > 16 || |
| 143 | plaintext[ciphertextlen - 1] > ciphertextlen) { |
| 144 | error_setg(errp, "Incorrect number of padding bytes (%d) " |
| 145 | "found on decrypted data", |
| 146 | (int)plaintext[ciphertextlen - 1]); |
| 147 | g_free(plaintext); |
| 148 | plaintext = NULL; |
| 149 | goto cleanup; |
| 150 | } |
| 151 | |
| 152 | /* Even though plaintext may contain arbitrary NUL |
| 153 | * ensure it is explicitly NUL terminated. |
| 154 | */ |
| 155 | ciphertextlen -= plaintext[ciphertextlen - 1]; |
| 156 | plaintext[ciphertextlen] = '\0'; |
| 157 | |
| 158 | *output = plaintext; |
| 159 | *outputlen = ciphertextlen; |
| 160 | |
| 161 | cleanup: |
| 162 | g_free(ciphertext); |
| 163 | g_free(iv); |
| 164 | g_free(key); |
| 165 | qcrypto_cipher_free(aes); |
| 166 | } |
| 167 | |
| 168 | |
| 169 | static void qcrypto_secret_decode(const uint8_t *input, |
| 170 | size_t inputlen, |
| 171 | uint8_t **output, |
| 172 | size_t *outputlen, |
| 173 | Error **errp) |
| 174 | { |
| 175 | *output = qbase64_decode((const gchar*)input, |
| 176 | inputlen, |
| 177 | outputlen, |
| 178 | errp); |
| 179 | } |
| 180 | |
| 181 | |
| 182 | static void |
| 183 | qcrypto_secret_prop_set_loaded(Object *obj, |
| 184 | bool value, |
| 185 | Error **errp) |
| 186 | { |
| 187 | QCryptoSecret *secret = QCRYPTO_SECRET(obj); |
| 188 | |
| 189 | if (value) { |
| 190 | Error *local_err = NULL; |
| 191 | uint8_t *input = NULL; |
| 192 | size_t inputlen = 0; |
| 193 | uint8_t *output = NULL; |
| 194 | size_t outputlen = 0; |
| 195 | |
| 196 | qcrypto_secret_load_data(secret, &input, &inputlen, &local_err); |
| 197 | if (local_err) { |
| 198 | error_propagate(errp, local_err); |
| 199 | return; |
| 200 | } |
| 201 | |
| 202 | if (secret->keyid) { |
| 203 | qcrypto_secret_decrypt(secret, input, inputlen, |
| 204 | &output, &outputlen, &local_err); |
| 205 | g_free(input); |
| 206 | if (local_err) { |
| 207 | error_propagate(errp, local_err); |
| 208 | return; |
| 209 | } |
| 210 | input = output; |
| 211 | inputlen = outputlen; |
| 212 | } else { |
| 213 | if (secret->format != QCRYPTO_SECRET_FORMAT_RAW) { |
| 214 | qcrypto_secret_decode(input, inputlen, |
| 215 | &output, &outputlen, &local_err); |
| 216 | g_free(input); |
| 217 | if (local_err) { |
| 218 | error_propagate(errp, local_err); |
| 219 | return; |
| 220 | } |
| 221 | input = output; |
| 222 | inputlen = outputlen; |
| 223 | } |
| 224 | } |
| 225 | |
| 226 | secret->rawdata = input; |
| 227 | secret->rawlen = inputlen; |
| 228 | } else { |
| 229 | g_free(secret->rawdata); |
| 230 | secret->rawlen = 0; |
| 231 | } |
| 232 | } |
| 233 | |
| 234 | |
| 235 | static bool |
| 236 | qcrypto_secret_prop_get_loaded(Object *obj, |
| 237 | Error **errp G_GNUC_UNUSED) |
| 238 | { |
| 239 | QCryptoSecret *secret = QCRYPTO_SECRET(obj); |
| 240 | return secret->data != NULL; |
| 241 | } |
| 242 | |
| 243 | |
| 244 | static void |
| 245 | qcrypto_secret_prop_set_format(Object *obj, |
| 246 | int value, |
| 247 | Error **errp G_GNUC_UNUSED) |
| 248 | { |
| 249 | QCryptoSecret *creds = QCRYPTO_SECRET(obj); |
| 250 | |
| 251 | creds->format = value; |
| 252 | } |
| 253 | |
| 254 | |
| 255 | static int |
| 256 | qcrypto_secret_prop_get_format(Object *obj, |
| 257 | Error **errp G_GNUC_UNUSED) |
| 258 | { |
| 259 | QCryptoSecret *creds = QCRYPTO_SECRET(obj); |
| 260 | |
| 261 | return creds->format; |
| 262 | } |
| 263 | |
| 264 | |
| 265 | static void |
| 266 | qcrypto_secret_prop_set_data(Object *obj, |
| 267 | const char *value, |
| 268 | Error **errp) |
| 269 | { |
| 270 | QCryptoSecret *secret = QCRYPTO_SECRET(obj); |
| 271 | |
| 272 | g_free(secret->data); |
| 273 | secret->data = g_strdup(value); |
| 274 | } |
| 275 | |
| 276 | |
| 277 | static char * |
| 278 | qcrypto_secret_prop_get_data(Object *obj, |
| 279 | Error **errp) |
| 280 | { |
| 281 | QCryptoSecret *secret = QCRYPTO_SECRET(obj); |
| 282 | return g_strdup(secret->data); |
| 283 | } |
| 284 | |
| 285 | |
| 286 | static void |
| 287 | qcrypto_secret_prop_set_file(Object *obj, |
| 288 | const char *value, |
| 289 | Error **errp) |
| 290 | { |
| 291 | QCryptoSecret *secret = QCRYPTO_SECRET(obj); |
| 292 | |
| 293 | g_free(secret->file); |
| 294 | secret->file = g_strdup(value); |
| 295 | } |
| 296 | |
| 297 | |
| 298 | static char * |
| 299 | qcrypto_secret_prop_get_file(Object *obj, |
| 300 | Error **errp) |
| 301 | { |
| 302 | QCryptoSecret *secret = QCRYPTO_SECRET(obj); |
| 303 | return g_strdup(secret->file); |
| 304 | } |
| 305 | |
| 306 | |
| 307 | static void |
| 308 | qcrypto_secret_prop_set_iv(Object *obj, |
| 309 | const char *value, |
| 310 | Error **errp) |
| 311 | { |
| 312 | QCryptoSecret *secret = QCRYPTO_SECRET(obj); |
| 313 | |
| 314 | g_free(secret->iv); |
| 315 | secret->iv = g_strdup(value); |
| 316 | } |
| 317 | |
| 318 | |
| 319 | static char * |
| 320 | qcrypto_secret_prop_get_iv(Object *obj, |
| 321 | Error **errp) |
| 322 | { |
| 323 | QCryptoSecret *secret = QCRYPTO_SECRET(obj); |
| 324 | return g_strdup(secret->iv); |
| 325 | } |
| 326 | |
| 327 | |
| 328 | static void |
| 329 | qcrypto_secret_prop_set_keyid(Object *obj, |
| 330 | const char *value, |
| 331 | Error **errp) |
| 332 | { |
| 333 | QCryptoSecret *secret = QCRYPTO_SECRET(obj); |
| 334 | |
| 335 | g_free(secret->keyid); |
| 336 | secret->keyid = g_strdup(value); |
| 337 | } |
| 338 | |
| 339 | |
| 340 | static char * |
| 341 | qcrypto_secret_prop_get_keyid(Object *obj, |
| 342 | Error **errp) |
| 343 | { |
| 344 | QCryptoSecret *secret = QCRYPTO_SECRET(obj); |
| 345 | return g_strdup(secret->keyid); |
| 346 | } |
| 347 | |
| 348 | |
| 349 | static void |
| 350 | qcrypto_secret_complete(UserCreatable *uc, Error **errp) |
| 351 | { |
| 352 | object_property_set_bool(OBJECT(uc), true, "loaded", errp); |
| 353 | } |
| 354 | |
| 355 | |
| 356 | static void |
Daniel P. Berrange | ac1d887 | 2015-10-14 09:58:38 +0100 | [diff] [blame] | 357 | qcrypto_secret_finalize(Object *obj) |
| 358 | { |
| 359 | QCryptoSecret *secret = QCRYPTO_SECRET(obj); |
| 360 | |
| 361 | g_free(secret->iv); |
| 362 | g_free(secret->file); |
| 363 | g_free(secret->keyid); |
| 364 | g_free(secret->rawdata); |
| 365 | g_free(secret->data); |
| 366 | } |
| 367 | |
| 368 | static void |
| 369 | qcrypto_secret_class_init(ObjectClass *oc, void *data) |
| 370 | { |
| 371 | UserCreatableClass *ucc = USER_CREATABLE_CLASS(oc); |
| 372 | |
| 373 | ucc->complete = qcrypto_secret_complete; |
Daniel P. Berrange | 9884abe | 2015-08-24 18:46:57 +0100 | [diff] [blame] | 374 | |
| 375 | object_class_property_add_bool(oc, "loaded", |
| 376 | qcrypto_secret_prop_get_loaded, |
| 377 | qcrypto_secret_prop_set_loaded, |
| 378 | NULL); |
| 379 | object_class_property_add_enum(oc, "format", |
| 380 | "QCryptoSecretFormat", |
Marc-André Lureau | f7abe0e | 2017-08-24 10:46:10 +0200 | [diff] [blame] | 381 | &QCryptoSecretFormat_lookup, |
Daniel P. Berrange | 9884abe | 2015-08-24 18:46:57 +0100 | [diff] [blame] | 382 | qcrypto_secret_prop_get_format, |
| 383 | qcrypto_secret_prop_set_format, |
| 384 | NULL); |
| 385 | object_class_property_add_str(oc, "data", |
| 386 | qcrypto_secret_prop_get_data, |
| 387 | qcrypto_secret_prop_set_data, |
| 388 | NULL); |
| 389 | object_class_property_add_str(oc, "file", |
| 390 | qcrypto_secret_prop_get_file, |
| 391 | qcrypto_secret_prop_set_file, |
| 392 | NULL); |
| 393 | object_class_property_add_str(oc, "keyid", |
| 394 | qcrypto_secret_prop_get_keyid, |
| 395 | qcrypto_secret_prop_set_keyid, |
| 396 | NULL); |
| 397 | object_class_property_add_str(oc, "iv", |
| 398 | qcrypto_secret_prop_get_iv, |
| 399 | qcrypto_secret_prop_set_iv, |
| 400 | NULL); |
Daniel P. Berrange | ac1d887 | 2015-10-14 09:58:38 +0100 | [diff] [blame] | 401 | } |
| 402 | |
| 403 | |
| 404 | int qcrypto_secret_lookup(const char *secretid, |
| 405 | uint8_t **data, |
| 406 | size_t *datalen, |
| 407 | Error **errp) |
| 408 | { |
| 409 | Object *obj; |
| 410 | QCryptoSecret *secret; |
| 411 | |
| 412 | obj = object_resolve_path_component( |
| 413 | object_get_objects_root(), secretid); |
| 414 | if (!obj) { |
| 415 | error_setg(errp, "No secret with id '%s'", secretid); |
| 416 | return -1; |
| 417 | } |
| 418 | |
| 419 | secret = (QCryptoSecret *) |
| 420 | object_dynamic_cast(obj, |
| 421 | TYPE_QCRYPTO_SECRET); |
| 422 | if (!secret) { |
| 423 | error_setg(errp, "Object with id '%s' is not a secret", |
| 424 | secretid); |
| 425 | return -1; |
| 426 | } |
| 427 | |
| 428 | if (!secret->rawdata) { |
| 429 | error_setg(errp, "Secret with id '%s' has no data", |
| 430 | secretid); |
| 431 | return -1; |
| 432 | } |
| 433 | |
Peter Maydell | d341d9f | 2016-01-22 15:09:21 +0000 | [diff] [blame] | 434 | *data = g_new0(uint8_t, secret->rawlen + 1); |
Daniel P. Berrange | ac1d887 | 2015-10-14 09:58:38 +0100 | [diff] [blame] | 435 | memcpy(*data, secret->rawdata, secret->rawlen); |
| 436 | (*data)[secret->rawlen] = '\0'; |
| 437 | *datalen = secret->rawlen; |
| 438 | |
| 439 | return 0; |
| 440 | } |
| 441 | |
| 442 | |
| 443 | char *qcrypto_secret_lookup_as_utf8(const char *secretid, |
| 444 | Error **errp) |
| 445 | { |
| 446 | uint8_t *data; |
| 447 | size_t datalen; |
| 448 | |
| 449 | if (qcrypto_secret_lookup(secretid, |
| 450 | &data, |
| 451 | &datalen, |
| 452 | errp) < 0) { |
| 453 | return NULL; |
| 454 | } |
| 455 | |
| 456 | if (!g_utf8_validate((const gchar*)data, datalen, NULL)) { |
| 457 | error_setg(errp, |
| 458 | "Data from secret %s is not valid UTF-8", |
| 459 | secretid); |
| 460 | g_free(data); |
| 461 | return NULL; |
| 462 | } |
| 463 | |
| 464 | return (char *)data; |
| 465 | } |
| 466 | |
| 467 | |
| 468 | char *qcrypto_secret_lookup_as_base64(const char *secretid, |
| 469 | Error **errp) |
| 470 | { |
| 471 | uint8_t *data; |
| 472 | size_t datalen; |
| 473 | char *ret; |
| 474 | |
| 475 | if (qcrypto_secret_lookup(secretid, |
| 476 | &data, |
| 477 | &datalen, |
| 478 | errp) < 0) { |
| 479 | return NULL; |
| 480 | } |
| 481 | |
| 482 | ret = g_base64_encode(data, datalen); |
| 483 | g_free(data); |
| 484 | return ret; |
| 485 | } |
| 486 | |
| 487 | |
| 488 | static const TypeInfo qcrypto_secret_info = { |
| 489 | .parent = TYPE_OBJECT, |
| 490 | .name = TYPE_QCRYPTO_SECRET, |
| 491 | .instance_size = sizeof(QCryptoSecret), |
Daniel P. Berrange | ac1d887 | 2015-10-14 09:58:38 +0100 | [diff] [blame] | 492 | .instance_finalize = qcrypto_secret_finalize, |
| 493 | .class_size = sizeof(QCryptoSecretClass), |
| 494 | .class_init = qcrypto_secret_class_init, |
| 495 | .interfaces = (InterfaceInfo[]) { |
| 496 | { TYPE_USER_CREATABLE }, |
| 497 | { } |
| 498 | } |
| 499 | }; |
| 500 | |
| 501 | |
| 502 | static void |
| 503 | qcrypto_secret_register_types(void) |
| 504 | { |
| 505 | type_register_static(&qcrypto_secret_info); |
| 506 | } |
| 507 | |
| 508 | |
| 509 | type_init(qcrypto_secret_register_types); |