The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2007 The Android Open Source Project |
| 3 | * |
| 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 5 | * you may not use this file except in compliance with the License. |
| 6 | * You may obtain a copy of the License at |
| 7 | * |
| 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 9 | * |
| 10 | * Unless required by applicable law or agreed to in writing, software |
| 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 13 | * See the License for the specific language governing permissions and |
| 14 | * limitations under the License. |
| 15 | */ |
| 16 | |
| 17 | #include <drm_rights_manager.h> |
| 18 | #include <drm_inner.h> |
| 19 | #include <drm_file.h> |
| 20 | #include <drm_i18n.h> |
| 21 | |
| 22 | static int32_t drm_getString(uint8_t* string, int32_t len, int32_t handle) |
| 23 | { |
| 24 | int32_t i; |
| 25 | |
| 26 | for (i = 0; i < len; i++) { |
| 27 | if (DRM_FILE_FAILURE == DRM_file_read(handle, &string[i], 1)) |
| 28 | return FALSE; |
| 29 | if (string[i] == '\n') { |
| 30 | string[i + 1] = '\0'; |
| 31 | break; |
| 32 | } |
| 33 | } |
| 34 | return TRUE; |
| 35 | } |
| 36 | |
| 37 | static int32_t drm_putString(uint8_t* string, int32_t handle) |
| 38 | { |
| 39 | int32_t i = 0; |
| 40 | |
| 41 | for (i = 0;; i++) { |
| 42 | if (string[i] == '\0') |
| 43 | break; |
| 44 | if (DRM_FILE_FAILURE == DRM_file_write(handle, &string[i], 1)) |
| 45 | return FALSE; |
| 46 | } |
| 47 | return TRUE; |
| 48 | } |
| 49 | |
| 50 | static int32_t drm_writeToUidTxt(uint8_t* Uid, int32_t* id) |
| 51 | { |
| 52 | int32_t length; |
| 53 | int32_t i; |
| 54 | uint8_t idStr[8]; |
| 55 | int32_t idMax; |
| 56 | uint8_t(*uidStr)[256]; |
| 57 | uint16_t nameUcs2[MAX_FILENAME_LEN]; |
| 58 | int32_t nameLen; |
| 59 | int32_t bytesConsumed; |
| 60 | int32_t handle; |
| 61 | int32_t fileRes; |
| 62 | |
| 63 | if (*id < 1) |
| 64 | return FALSE; |
| 65 | |
| 66 | /* convert in ucs2 */ |
| 67 | nameLen = strlen(DRM_UID_FILE_PATH); |
| 68 | nameLen = DRM_i18n_mbsToWcs(DRM_CHARSET_UTF8, |
| 69 | (uint8_t *)DRM_UID_FILE_PATH, |
| 70 | nameLen, |
| 71 | nameUcs2, |
| 72 | MAX_FILENAME_LEN, |
| 73 | &bytesConsumed); |
| 74 | fileRes = DRM_file_open(nameUcs2, |
| 75 | nameLen, |
| 76 | DRM_FILE_MODE_READ, |
| 77 | &handle); |
| 78 | if (DRM_FILE_SUCCESS != fileRes) { |
| 79 | DRM_file_open(nameUcs2, |
| 80 | nameLen, |
| 81 | DRM_FILE_MODE_WRITE, |
| 82 | &handle); |
| 83 | DRM_file_write(handle, (uint8_t *)"0\n", 2); |
| 84 | DRM_file_close(handle); |
| 85 | DRM_file_open(nameUcs2, |
| 86 | nameLen, |
| 87 | DRM_FILE_MODE_READ, |
| 88 | &handle); |
| 89 | } |
| 90 | |
| 91 | if (!drm_getString(idStr, 8, handle)) { |
| 92 | DRM_file_close(handle); |
| 93 | return FALSE; |
| 94 | } |
| 95 | idMax = atoi((char *)idStr); |
| 96 | |
| 97 | if (idMax < *id) |
| 98 | uidStr = malloc((idMax + 1) * 256); |
| 99 | else |
| 100 | uidStr = malloc(idMax * 256); |
| 101 | |
| 102 | for (i = 0; i < idMax; i++) { |
| 103 | if (!drm_getString(uidStr[i], 256, handle)) { |
| 104 | DRM_file_close(handle); |
| 105 | free(uidStr); |
| 106 | return FALSE; |
| 107 | } |
| 108 | } |
| 109 | length = strlen((char *)Uid); |
| 110 | strcpy((char *)uidStr[*id - 1], (char *)Uid); |
| 111 | uidStr[*id - 1][length] = '\n'; |
| 112 | uidStr[*id - 1][length + 1] = '\0'; |
| 113 | if (idMax < (*id)) |
| 114 | idMax++; |
| 115 | DRM_file_close(handle); |
| 116 | |
| 117 | DRM_file_open(nameUcs2, |
| 118 | nameLen, |
| 119 | DRM_FILE_MODE_WRITE, |
| 120 | &handle); |
| 121 | sprintf((char *)idStr, "%d", idMax); |
| 122 | |
| 123 | if (!drm_putString(idStr, handle)) { |
| 124 | DRM_file_close(handle); |
| 125 | free(uidStr); |
| 126 | return FALSE; |
| 127 | } |
| 128 | if (DRM_FILE_FAILURE == DRM_file_write(handle, (uint8_t *)"\n", 1)) { |
| 129 | DRM_file_close(handle); |
| 130 | free(uidStr); |
| 131 | return FALSE; |
| 132 | } |
| 133 | for (i = 0; i < idMax; i++) { |
| 134 | if (!drm_putString(uidStr[i], handle)) { |
| 135 | DRM_file_close(handle); |
| 136 | free(uidStr); |
| 137 | return FALSE; |
| 138 | } |
| 139 | } |
| 140 | if (DRM_FILE_FAILURE == DRM_file_write(handle, (uint8_t *)"\n", 1)) { |
| 141 | DRM_file_close(handle); |
| 142 | free(uidStr); |
| 143 | return FALSE; |
| 144 | } |
| 145 | DRM_file_close(handle); |
| 146 | free(uidStr); |
| 147 | return TRUE; |
| 148 | } |
| 149 | |
| 150 | /* See objmng_files.h */ |
| 151 | int32_t drm_readFromUidTxt(uint8_t* Uid, int32_t* id, int32_t option) |
| 152 | { |
| 153 | int32_t i; |
| 154 | uint8_t p[256] = { 0 }; |
| 155 | uint8_t idStr[8]; |
| 156 | int32_t idMax = 0; |
| 157 | uint16_t nameUcs2[MAX_FILENAME_LEN]; |
| 158 | int32_t nameLen = 0; |
| 159 | int32_t bytesConsumed; |
| 160 | int32_t handle; |
| 161 | int32_t fileRes; |
| 162 | |
| 163 | if (NULL == id || NULL == Uid) |
| 164 | return FALSE; |
| 165 | |
| 166 | DRM_file_startup(); |
| 167 | |
| 168 | /* convert in ucs2 */ |
| 169 | nameLen = strlen(DRM_UID_FILE_PATH); |
| 170 | nameLen = DRM_i18n_mbsToWcs(DRM_CHARSET_UTF8, |
| 171 | (uint8_t *)DRM_UID_FILE_PATH, |
| 172 | nameLen, |
| 173 | nameUcs2, |
| 174 | MAX_FILENAME_LEN, |
| 175 | &bytesConsumed); |
| 176 | fileRes = DRM_file_open(nameUcs2, |
| 177 | nameLen, |
| 178 | DRM_FILE_MODE_READ, |
| 179 | &handle); |
| 180 | if (DRM_FILE_SUCCESS != fileRes) { |
| 181 | DRM_file_open(nameUcs2, |
| 182 | nameLen, |
| 183 | DRM_FILE_MODE_WRITE, |
| 184 | &handle); |
| 185 | DRM_file_write(handle, (uint8_t *)"0\n", 2); |
| 186 | DRM_file_close(handle); |
| 187 | DRM_file_open(nameUcs2, |
| 188 | nameLen, |
| 189 | DRM_FILE_MODE_READ, |
| 190 | &handle); |
| 191 | } |
| 192 | |
| 193 | if (!drm_getString(idStr, 8, handle)) { |
| 194 | DRM_file_close(handle); |
| 195 | return FALSE; |
| 196 | } |
| 197 | idMax = atoi((char *)idStr); |
| 198 | |
| 199 | if (option == GET_UID) { |
| 200 | if (*id < 1 || *id > idMax) { |
| 201 | DRM_file_close(handle); |
| 202 | return FALSE; |
| 203 | } |
| 204 | for (i = 1; i <= *id; i++) { |
| 205 | if (!drm_getString(Uid, 256, handle)) { |
| 206 | DRM_file_close(handle); |
| 207 | return FALSE; |
| 208 | } |
| 209 | } |
| 210 | DRM_file_close(handle); |
| 211 | return TRUE; |
| 212 | } |
| 213 | if (option == GET_ID) { |
| 214 | *id = -1; |
| 215 | for (i = 1; i <= idMax; i++) { |
| 216 | if (!drm_getString(p, 256, handle)) { |
| 217 | DRM_file_close(handle); |
| 218 | return FALSE; |
| 219 | } |
| 220 | if (strstr((char *)p, (char *)Uid) != NULL |
| 221 | && strlen((char *)p) == strlen((char *)Uid) + 1) { |
| 222 | *id = i; |
| 223 | DRM_file_close(handle); |
| 224 | return TRUE; |
| 225 | } |
| 226 | if ((*id == -1) && (strlen((char *)p) < 3)) |
| 227 | *id = i; |
| 228 | } |
| 229 | if (*id != -1) { |
| 230 | DRM_file_close(handle); |
| 231 | return FALSE; |
| 232 | } |
| 233 | *id = idMax + 1; |
| 234 | DRM_file_close(handle); |
| 235 | return FALSE; |
| 236 | } |
| 237 | DRM_file_close(handle); |
| 238 | return FALSE; |
| 239 | } |
| 240 | |
| 241 | static int32_t drm_acquireId(uint8_t* uid, int32_t* id) |
| 242 | { |
| 243 | if (TRUE == drm_readFromUidTxt(uid, id, GET_ID)) |
| 244 | return TRUE; |
| 245 | |
| 246 | drm_writeToUidTxt(uid, id); |
| 247 | |
| 248 | return FALSE; /* The Uid is not exit, then return FALSE indicate it */ |
| 249 | } |
| 250 | |
| 251 | int32_t drm_writeOrReadInfo(int32_t id, T_DRM_Rights* Ro, int32_t* RoAmount, int32_t option) |
| 252 | { |
| 253 | uint8_t fullname[MAX_FILENAME_LEN] = {0}; |
| 254 | int32_t tmpRoAmount; |
| 255 | uint16_t nameUcs2[MAX_FILENAME_LEN]; |
| 256 | int32_t nameLen = 0; |
| 257 | int32_t bytesConsumed; |
| 258 | int32_t handle; |
| 259 | int32_t fileRes; |
| 260 | |
| 261 | sprintf((char *)fullname, ANDROID_DRM_CORE_PATH"%d"EXTENSION_NAME_INFO, id); |
| 262 | |
| 263 | /* convert in ucs2 */ |
| 264 | nameLen = strlen((char *)fullname); |
| 265 | nameLen = DRM_i18n_mbsToWcs(DRM_CHARSET_UTF8, |
| 266 | fullname, |
| 267 | nameLen, |
| 268 | nameUcs2, |
| 269 | MAX_FILENAME_LEN, |
| 270 | &bytesConsumed); |
| 271 | fileRes = DRM_file_open(nameUcs2, |
| 272 | nameLen, |
| 273 | DRM_FILE_MODE_READ, |
| 274 | &handle); |
| 275 | if (DRM_FILE_SUCCESS != fileRes) { |
| 276 | if (GET_ALL_RO == option || GET_A_RO == option) |
| 277 | return FALSE; |
| 278 | |
| 279 | if (GET_ROAMOUNT == option) { |
| 280 | *RoAmount = -1; |
| 281 | return TRUE; |
| 282 | } |
| 283 | } |
| 284 | |
| 285 | DRM_file_close(handle); |
| 286 | DRM_file_open(nameUcs2, |
| 287 | nameLen, |
| 288 | DRM_FILE_MODE_READ | DRM_FILE_MODE_WRITE, |
| 289 | &handle); |
| 290 | |
| 291 | switch(option) { |
| 292 | case GET_ROAMOUNT: |
| 293 | if (DRM_FILE_FAILURE == DRM_file_read(handle, (uint8_t*)RoAmount, sizeof(int32_t))) { |
| 294 | DRM_file_close(handle); |
| 295 | return FALSE; |
| 296 | } |
| 297 | break; |
| 298 | case GET_ALL_RO: |
| 299 | DRM_file_setPosition(handle, sizeof(int32_t)); |
| 300 | |
| 301 | if (DRM_FILE_FAILURE == DRM_file_read(handle, (uint8_t*)Ro, (*RoAmount) * sizeof(T_DRM_Rights))) { |
| 302 | DRM_file_close(handle); |
| 303 | return FALSE; |
| 304 | } |
| 305 | break; |
| 306 | case SAVE_ALL_RO: |
| 307 | if (DRM_FILE_FAILURE == DRM_file_write(handle, (uint8_t*)RoAmount, sizeof(int32_t))) { |
| 308 | DRM_file_close(handle); |
| 309 | return FALSE; |
| 310 | } |
| 311 | |
| 312 | if (NULL != Ro && *RoAmount >= 1) { |
| 313 | if (DRM_FILE_FAILURE == DRM_file_write(handle, (uint8_t*) Ro, (*RoAmount) * sizeof(T_DRM_Rights))) { |
| 314 | DRM_file_close(handle); |
| 315 | return FALSE; |
| 316 | } |
| 317 | } |
| 318 | break; |
| 319 | case GET_A_RO: |
| 320 | DRM_file_setPosition(handle, sizeof(int32_t) + (*RoAmount - 1) * sizeof(T_DRM_Rights)); |
| 321 | |
| 322 | if (DRM_FILE_FAILURE == DRM_file_read(handle, (uint8_t*)Ro, sizeof(T_DRM_Rights))) { |
| 323 | DRM_file_close(handle); |
| 324 | return FALSE; |
| 325 | } |
| 326 | break; |
| 327 | case SAVE_A_RO: |
| 328 | DRM_file_setPosition(handle, sizeof(int32_t) + (*RoAmount - 1) * sizeof(T_DRM_Rights)); |
| 329 | |
| 330 | if (DRM_FILE_FAILURE == DRM_file_write(handle, (uint8_t*)Ro, sizeof(T_DRM_Rights))) { |
| 331 | DRM_file_close(handle); |
| 332 | return FALSE; |
| 333 | } |
| 334 | |
| 335 | DRM_file_setPosition(handle, 0); |
| 336 | if (DRM_FILE_FAILURE == DRM_file_read(handle, (uint8_t*)&tmpRoAmount, sizeof(int32_t))) { |
| 337 | DRM_file_close(handle); |
| 338 | return FALSE; |
| 339 | } |
| 340 | if (tmpRoAmount < *RoAmount) { |
| 341 | DRM_file_setPosition(handle, 0); |
| 342 | DRM_file_write(handle, (uint8_t*)RoAmount, sizeof(int32_t)); |
| 343 | } |
| 344 | break; |
| 345 | default: |
| 346 | DRM_file_close(handle); |
| 347 | return FALSE; |
| 348 | } |
| 349 | |
| 350 | DRM_file_close(handle); |
| 351 | return TRUE; |
| 352 | } |
| 353 | |
| 354 | int32_t drm_appendRightsInfo(T_DRM_Rights* rights) |
| 355 | { |
| 356 | int32_t id; |
| 357 | int32_t roAmount; |
| 358 | |
| 359 | if (NULL == rights) |
| 360 | return FALSE; |
| 361 | |
| 362 | drm_acquireId(rights->uid, &id); |
| 363 | |
| 364 | if (FALSE == drm_writeOrReadInfo(id, NULL, &roAmount, GET_ROAMOUNT)) |
| 365 | return FALSE; |
| 366 | |
| 367 | if (-1 == roAmount) |
| 368 | roAmount = 0; |
| 369 | |
| 370 | /* The RO amount increase */ |
| 371 | roAmount++; |
| 372 | |
| 373 | /* Save the rights information */ |
| 374 | if (FALSE == drm_writeOrReadInfo(id, rights, &roAmount, SAVE_A_RO)) |
| 375 | return FALSE; |
| 376 | |
| 377 | return TRUE; |
| 378 | } |
| 379 | |
| 380 | int32_t drm_getMaxIdFromUidTxt() |
| 381 | { |
| 382 | uint8_t idStr[8]; |
| 383 | int32_t idMax = 0; |
| 384 | uint16_t nameUcs2[MAX_FILENAME_LEN] = {0}; |
| 385 | int32_t nameLen = 0; |
| 386 | int32_t bytesConsumed; |
| 387 | int32_t handle; |
| 388 | int32_t fileRes; |
| 389 | |
| 390 | /* convert in ucs2 */ |
| 391 | nameLen = strlen(DRM_UID_FILE_PATH); |
| 392 | nameLen = DRM_i18n_mbsToWcs(DRM_CHARSET_UTF8, |
| 393 | (uint8_t *)DRM_UID_FILE_PATH, |
| 394 | nameLen, |
| 395 | nameUcs2, |
| 396 | MAX_FILENAME_LEN, |
| 397 | &bytesConsumed); |
| 398 | fileRes = DRM_file_open(nameUcs2, |
| 399 | nameLen, |
| 400 | DRM_FILE_MODE_READ, |
| 401 | &handle); |
| 402 | |
| 403 | /* this means the uid.txt file is not exist, so there is not any DRM object */ |
| 404 | if (DRM_FILE_SUCCESS != fileRes) |
| 405 | return 0; |
| 406 | |
| 407 | if (!drm_getString(idStr, 8, handle)) { |
| 408 | DRM_file_close(handle); |
| 409 | return -1; |
| 410 | } |
| 411 | DRM_file_close(handle); |
| 412 | |
| 413 | idMax = atoi((char *)idStr); |
| 414 | return idMax; |
| 415 | } |
| 416 | |
| 417 | int32_t drm_removeIdInfoFile(int32_t id) |
| 418 | { |
| 419 | uint8_t filename[MAX_FILENAME_LEN] = {0}; |
| 420 | uint16_t nameUcs2[MAX_FILENAME_LEN]; |
| 421 | int32_t nameLen = 0; |
| 422 | int32_t bytesConsumed; |
| 423 | |
| 424 | if (id <= 0) |
| 425 | return FALSE; |
| 426 | |
| 427 | sprintf((char *)filename, ANDROID_DRM_CORE_PATH"%d"EXTENSION_NAME_INFO, id); |
| 428 | |
| 429 | /* convert in ucs2 */ |
| 430 | nameLen = strlen((char *)filename); |
| 431 | nameLen = DRM_i18n_mbsToWcs(DRM_CHARSET_UTF8, |
| 432 | filename, |
| 433 | nameLen, |
| 434 | nameUcs2, |
| 435 | MAX_FILENAME_LEN, |
| 436 | &bytesConsumed); |
| 437 | if (DRM_FILE_SUCCESS != DRM_file_delete(nameUcs2, nameLen)) |
| 438 | return FALSE; |
| 439 | |
| 440 | return TRUE; |
| 441 | } |
| 442 | |
| 443 | int32_t drm_updateUidTxtWhenDelete(int32_t id) |
| 444 | { |
| 445 | uint16_t nameUcs2[MAX_FILENAME_LEN]; |
| 446 | int32_t nameLen = 0; |
| 447 | int32_t bytesConsumed; |
| 448 | int32_t handle; |
| 449 | int32_t fileRes; |
| 450 | int32_t bufferLen; |
| 451 | uint8_t *buffer; |
| 452 | uint8_t idStr[8]; |
| 453 | int32_t idMax; |
| 454 | |
| 455 | if (id <= 0) |
| 456 | return FALSE; |
| 457 | |
| 458 | nameLen = strlen(DRM_UID_FILE_PATH); |
| 459 | nameLen = DRM_i18n_mbsToWcs(DRM_CHARSET_UTF8, |
| 460 | (uint8_t *)DRM_UID_FILE_PATH, |
| 461 | nameLen, |
| 462 | nameUcs2, |
| 463 | MAX_FILENAME_LEN, |
| 464 | &bytesConsumed); |
| 465 | bufferLen = DRM_file_getFileLength(nameUcs2, nameLen); |
| 466 | if (bufferLen <= 0) |
| 467 | return FALSE; |
| 468 | |
| 469 | buffer = (uint8_t *)malloc(bufferLen); |
| 470 | if (NULL == buffer) |
| 471 | return FALSE; |
| 472 | |
| 473 | fileRes = DRM_file_open(nameUcs2, |
| 474 | nameLen, |
| 475 | DRM_FILE_MODE_READ, |
| 476 | &handle); |
| 477 | if (DRM_FILE_SUCCESS != fileRes) { |
| 478 | free(buffer); |
| 479 | return FALSE; |
| 480 | } |
| 481 | |
| 482 | drm_getString(idStr, 8, handle); |
| 483 | idMax = atoi((char *)idStr); |
| 484 | |
| 485 | bufferLen -= strlen((char *)idStr); |
| 486 | fileRes = DRM_file_read(handle, buffer, bufferLen); |
| 487 | buffer[bufferLen] = '\0'; |
| 488 | DRM_file_close(handle); |
| 489 | |
| 490 | /* handle this buffer */ |
| 491 | { |
| 492 | uint8_t *pStart, *pEnd; |
| 493 | int32_t i, movLen; |
| 494 | |
| 495 | pStart = buffer; |
| 496 | pEnd = pStart; |
| 497 | for (i = 0; i < id; i++) { |
| 498 | if (pEnd != pStart) |
| 499 | pStart = ++pEnd; |
| 500 | while ('\n' != *pEnd) |
| 501 | pEnd++; |
| 502 | if (pStart == pEnd) |
| 503 | pStart--; |
| 504 | } |
| 505 | movLen = bufferLen - (pEnd - buffer); |
| 506 | memmove(pStart, pEnd, movLen); |
| 507 | bufferLen -= (pEnd - pStart); |
| 508 | } |
| 509 | |
| 510 | if (DRM_FILE_SUCCESS != DRM_file_delete(nameUcs2, nameLen)) { |
| 511 | free(buffer); |
| 512 | return FALSE; |
| 513 | } |
| 514 | |
| 515 | fileRes = DRM_file_open(nameUcs2, |
| 516 | nameLen, |
| 517 | DRM_FILE_MODE_WRITE, |
| 518 | &handle); |
| 519 | if (DRM_FILE_SUCCESS != fileRes) { |
| 520 | free(buffer); |
| 521 | return FALSE; |
| 522 | } |
| 523 | sprintf((char *)idStr, "%d", idMax); |
| 524 | drm_putString(idStr, handle); |
| 525 | DRM_file_write(handle, (uint8_t*)"\n", 1); |
| 526 | DRM_file_write(handle, buffer, bufferLen); |
| 527 | free(buffer); |
| 528 | DRM_file_close(handle); |
| 529 | return TRUE; |
| 530 | } |
| 531 | |
| 532 | int32_t drm_getKey(uint8_t* uid, uint8_t* KeyValue) |
| 533 | { |
| 534 | T_DRM_Rights ro; |
| 535 | int32_t id, roAmount; |
| 536 | |
| 537 | if (NULL == uid || NULL == KeyValue) |
| 538 | return FALSE; |
| 539 | |
| 540 | if (FALSE == drm_readFromUidTxt(uid, &id, GET_ID)) |
| 541 | return FALSE; |
| 542 | |
| 543 | if (FALSE == drm_writeOrReadInfo(id, NULL, &roAmount, GET_ROAMOUNT)) |
| 544 | return FALSE; |
| 545 | |
| 546 | if (roAmount <= 0) |
| 547 | return FALSE; |
| 548 | |
| 549 | memset(&ro, 0, sizeof(T_DRM_Rights)); |
| 550 | roAmount = 1; |
| 551 | if (FALSE == drm_writeOrReadInfo(id, &ro, &roAmount, GET_A_RO)) |
| 552 | return FALSE; |
| 553 | |
| 554 | memcpy(KeyValue, ro.KeyValue, DRM_KEY_LEN); |
| 555 | return TRUE; |
| 556 | } |
| 557 | |
| 558 | void drm_discardPaddingByte(uint8_t *decryptedBuf, int32_t *decryptedBufLen) |
| 559 | { |
| 560 | int32_t tmpLen = *decryptedBufLen; |
| 561 | int32_t i; |
| 562 | |
| 563 | if (NULL == decryptedBuf || *decryptedBufLen < 0) |
| 564 | return; |
| 565 | |
| 566 | /* Check whether the last several bytes are padding or not */ |
| 567 | for (i = 1; i < decryptedBuf[tmpLen - 1]; i++) { |
| 568 | if (decryptedBuf[tmpLen - 1 - i] != decryptedBuf[tmpLen - 1]) |
| 569 | break; /* Not the padding bytes */ |
| 570 | } |
| 571 | if (i == decryptedBuf[tmpLen - 1]) /* They are padding bytes */ |
| 572 | *decryptedBufLen = tmpLen - i; |
| 573 | return; |
| 574 | } |
| 575 | |
Chia-chi Yeh | 64e69e8 | 2009-08-06 02:28:24 +0800 | [diff] [blame] | 576 | int32_t drm_aesDecBuffer(uint8_t * Buffer, int32_t * BufferLen, AES_KEY *key) |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 577 | { |
| 578 | uint8_t dbuf[3 * DRM_ONE_AES_BLOCK_LEN], buf[DRM_ONE_AES_BLOCK_LEN]; |
| 579 | uint64_t i, len, wlen = DRM_ONE_AES_BLOCK_LEN, curLen, restLen; |
| 580 | uint8_t *pTarget, *pTargetHead; |
| 581 | |
| 582 | pTargetHead = Buffer; |
| 583 | pTarget = Buffer; |
| 584 | curLen = 0; |
| 585 | restLen = *BufferLen; |
| 586 | |
| 587 | if (restLen > 2 * DRM_ONE_AES_BLOCK_LEN) { |
| 588 | len = 2 * DRM_ONE_AES_BLOCK_LEN; |
| 589 | } else { |
| 590 | len = restLen; |
| 591 | } |
| 592 | memcpy(dbuf, Buffer, (size_t)len); |
| 593 | restLen -= len; |
| 594 | Buffer += len; |
| 595 | |
| 596 | if (len < 2 * DRM_ONE_AES_BLOCK_LEN) { /* The original file is less than one block in length */ |
| 597 | len -= DRM_ONE_AES_BLOCK_LEN; |
| 598 | /* Decrypt from position len to position len + DRM_ONE_AES_BLOCK_LEN */ |
Chia-chi Yeh | 64e69e8 | 2009-08-06 02:28:24 +0800 | [diff] [blame] | 599 | AES_decrypt((dbuf + len), (dbuf + len), key); |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 600 | |
| 601 | /* Undo the CBC chaining */ |
| 602 | for (i = 0; i < len; ++i) |
| 603 | dbuf[i] ^= dbuf[i + DRM_ONE_AES_BLOCK_LEN]; |
| 604 | |
| 605 | /* Output the decrypted bytes */ |
| 606 | memcpy(pTarget, dbuf, (size_t)len); |
| 607 | pTarget += len; |
| 608 | } else { |
| 609 | uint8_t *b1 = dbuf, *b2 = b1 + DRM_ONE_AES_BLOCK_LEN, *b3 = b2 + DRM_ONE_AES_BLOCK_LEN, *bt; |
| 610 | |
| 611 | for (;;) { /* While some ciphertext remains, prepare to decrypt block b2 */ |
| 612 | /* Read in the next block to see if ciphertext stealing is needed */ |
| 613 | b3 = Buffer; |
| 614 | if (restLen > DRM_ONE_AES_BLOCK_LEN) { |
| 615 | len = DRM_ONE_AES_BLOCK_LEN; |
| 616 | } else { |
| 617 | len = restLen; |
| 618 | } |
| 619 | restLen -= len; |
| 620 | Buffer += len; |
| 621 | |
| 622 | /* Decrypt the b2 block */ |
Chia-chi Yeh | 64e69e8 | 2009-08-06 02:28:24 +0800 | [diff] [blame] | 623 | AES_decrypt((uint8_t *)b2, buf, key); |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 624 | |
| 625 | if (len == 0 || len == DRM_ONE_AES_BLOCK_LEN) { /* No ciphertext stealing */ |
| 626 | /* Unchain CBC using the previous ciphertext block in b1 */ |
| 627 | for (i = 0; i < DRM_ONE_AES_BLOCK_LEN; ++i) |
| 628 | buf[i] ^= b1[i]; |
| 629 | } else { /* Partial last block - use ciphertext stealing */ |
| 630 | wlen = len; |
| 631 | /* Produce last 'len' bytes of plaintext by xoring with */ |
| 632 | /* The lowest 'len' bytes of next block b3 - C[N-1] */ |
| 633 | for (i = 0; i < len; ++i) |
| 634 | buf[i] ^= b3[i]; |
| 635 | |
| 636 | /* Reconstruct the C[N-1] block in b3 by adding in the */ |
| 637 | /* Last (DRM_ONE_AES_BLOCK_LEN - len) bytes of C[N-2] in b2 */ |
| 638 | for (i = len; i < DRM_ONE_AES_BLOCK_LEN; ++i) |
| 639 | b3[i] = buf[i]; |
| 640 | |
| 641 | /* Decrypt the C[N-1] block in b3 */ |
Chia-chi Yeh | 64e69e8 | 2009-08-06 02:28:24 +0800 | [diff] [blame] | 642 | AES_decrypt((uint8_t *)b3, (uint8_t *)b3, key); |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 643 | |
| 644 | /* Produce the last but one plaintext block by xoring with */ |
| 645 | /* The last but two ciphertext block */ |
| 646 | for (i = 0; i < DRM_ONE_AES_BLOCK_LEN; ++i) |
| 647 | b3[i] ^= b1[i]; |
| 648 | |
| 649 | /* Write decrypted plaintext blocks */ |
| 650 | memcpy(pTarget, b3, DRM_ONE_AES_BLOCK_LEN); |
| 651 | pTarget += DRM_ONE_AES_BLOCK_LEN; |
| 652 | } |
| 653 | |
| 654 | /* Write the decrypted plaintext block */ |
| 655 | memcpy(pTarget, buf, (size_t)wlen); |
| 656 | pTarget += wlen; |
| 657 | |
| 658 | if (len != DRM_ONE_AES_BLOCK_LEN) { |
| 659 | *BufferLen = pTarget - pTargetHead; |
| 660 | return 0; |
| 661 | } |
| 662 | |
| 663 | /* Advance the buffer pointers */ |
| 664 | bt = b1, b1 = b2, b2 = b3, b3 = bt; |
| 665 | } |
| 666 | } |
| 667 | return 0; |
| 668 | } |
| 669 | |
| 670 | int32_t drm_updateDcfDataLen(uint8_t* pDcfLastData, uint8_t* keyValue, int32_t* moreBytes) |
| 671 | { |
Chia-chi Yeh | 64e69e8 | 2009-08-06 02:28:24 +0800 | [diff] [blame] | 672 | AES_KEY key; |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 673 | int32_t len = DRM_TWO_AES_BLOCK_LEN; |
| 674 | |
| 675 | if (NULL == pDcfLastData || NULL == keyValue) |
| 676 | return FALSE; |
| 677 | |
Chia-chi Yeh | 64e69e8 | 2009-08-06 02:28:24 +0800 | [diff] [blame] | 678 | AES_set_decrypt_key(keyValue, DRM_KEY_LEN * 8, &key); |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 679 | |
Chia-chi Yeh | 64e69e8 | 2009-08-06 02:28:24 +0800 | [diff] [blame] | 680 | if (drm_aesDecBuffer(pDcfLastData, &len, &key) < 0) |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 681 | return FALSE; |
| 682 | |
| 683 | drm_discardPaddingByte(pDcfLastData, &len); |
| 684 | |
| 685 | *moreBytes = DRM_TWO_AES_BLOCK_LEN - len; |
| 686 | |
| 687 | return TRUE; |
| 688 | } |