1 /* 2 * CDDL HEADER START 3 * 4 * This file and its contents are supplied under the terms of the 5 * Common Development and Distribution License ("CDDL"), version 1.0. 6 * You may only use this file in accordance with the terms of version 7 * 1.0 of the CDDL. 8 * 9 * A full copy of the text of the CDDL should have accompanied this 10 * source. A copy of the CDDL is also available via the Internet at 11 * http://www.illumos.org/license/CDDL. 12 * 13 * CDDL HEADER END 14 */ 15 16 /* 17 * Copyright (c) 2017, Datto, Inc. All rights reserved. 18 */ 19 20 #include <sys/zio_crypt.h> 21 #include <sys/dmu.h> 22 #include <sys/dmu_objset.h> 23 #include <sys/dnode.h> 24 #include <sys/fs/zfs.h> 25 #include <sys/zio.h> 26 #include <sys/zil.h> 27 #include <sys/sha2.h> 28 #include <sys/hkdf.h> 29 30 /* 31 * This file is responsible for handling all of the details of generating 32 * encryption parameters and performing encryption and authentication. 33 * 34 * BLOCK ENCRYPTION PARAMETERS: 35 * Encryption /Authentication Algorithm Suite (crypt): 36 * The encryption algorithm, mode, and key length we are going to use. We 37 * currently support AES in either GCM or CCM modes with 128, 192, and 256 bit 38 * keys. All authentication is currently done with SHA512-HMAC. 39 * 40 * Plaintext: 41 * The unencrypted data that we want to encrypt. 42 * 43 * Initialization Vector (IV): 44 * An initialization vector for the encryption algorithms. This is used to 45 * "tweak" the encryption algorithms so that two blocks of the same data are 46 * encrypted into different ciphertext outputs, thus obfuscating block patterns. 47 * The supported encryption modes (AES-GCM and AES-CCM) require that an IV is 48 * never reused with the same encryption key. This value is stored unencrypted 49 * and must simply be provided to the decryption function. We use a 96 bit IV 50 * (as recommended by NIST) for all block encryption. For non-dedup blocks we 51 * derive the IV randomly. The first 64 bits of the IV are stored in the second 52 * word of DVA[2] and the remaining 32 bits are stored in the upper 32 bits of 53 * blk_fill. This is safe because encrypted blocks can't use the upper 32 bits 54 * of blk_fill. We only encrypt level 0 blocks, which normally have a fill count 55 * of 1. The only exception is for DMU_OT_DNODE objects, where the fill count of 56 * level 0 blocks is the number of allocated dnodes in that block. The on-disk 57 * format supports at most 2^15 slots per L0 dnode block, because the maximum 58 * block size is 16MB (2^24). In either case, for level 0 blocks this number 59 * will still be smaller than UINT32_MAX so it is safe to store the IV in the 60 * top 32 bits of blk_fill, while leaving the bottom 32 bits of the fill count 61 * for the dnode code. 62 * 63 * Master key: 64 * This is the most important secret data of an encrypted dataset. It is used 65 * along with the salt to generate that actual encryption keys via HKDF. We 66 * do not use the master key to directly encrypt any data because there are 67 * theoretical limits on how much data can actually be safely encrypted with 68 * any encryption mode. The master key is stored encrypted on disk with the 69 * user's wrapping key. Its length is determined by the encryption algorithm. 70 * For details on how this is stored see the block comment in dsl_crypt.c 71 * 72 * Salt: 73 * Used as an input to the HKDF function, along with the master key. We use a 74 * 64 bit salt, stored unencrypted in the first word of DVA[2]. Any given salt 75 * can be used for encrypting many blocks, so we cache the current salt and the 76 * associated derived key in zio_crypt_t so we do not need to derive it again 77 * needlessly. 78 * 79 * Encryption Key: 80 * A secret binary key, generated from an HKDF function used to encrypt and 81 * decrypt data. 82 * 83 * Message Authentication Code (MAC) 84 * The MAC is an output of authenticated encryption modes such as AES-GCM and 85 * AES-CCM. Its purpose is to ensure that an attacker cannot modify encrypted 86 * data on disk and return garbage to the application. Effectively, it is a 87 * checksum that can not be reproduced by an attacker. We store the MAC in the 88 * second 128 bits of blk_cksum, leaving the first 128 bits for a truncated 89 * regular checksum of the ciphertext which can be used for scrubbing. 90 * 91 * OBJECT AUTHENTICATION: 92 * Some object types, such as DMU_OT_MASTER_NODE cannot be encrypted because 93 * they contain some info that always needs to be readable. To prevent this 94 * data from being altered, we authenticate this data using SHA512-HMAC. This 95 * will produce a MAC (similar to the one produced via encryption) which can 96 * be used to verify the object was not modified. HMACs do not require key 97 * rotation or IVs, so we can keep up to the full 3 copies of authenticated 98 * data. 99 * 100 * ZIL ENCRYPTION: 101 * ZIL blocks have their bp written to disk ahead of the associated data, so we 102 * cannot store the MAC there as we normally do. For these blocks the MAC is 103 * stored in the embedded checksum within the zil_chain_t header. The salt and 104 * IV are generated for the block on bp allocation instead of at encryption 105 * time. In addition, ZIL blocks have some pieces that must be left in plaintext 106 * for claiming even though all of the sensitive user data still needs to be 107 * encrypted. The function zio_crypt_init_uios_zil() handles parsing which 108 * pieces of the block need to be encrypted. All data that is not encrypted is 109 * authenticated using the AAD mechanisms that the supported encryption modes 110 * provide for. In order to preserve the semantics of the ZIL for encrypted 111 * datasets, the ZIL is not protected at the objset level as described below. 112 * 113 * DNODE ENCRYPTION: 114 * Similarly to ZIL blocks, the core part of each dnode_phys_t needs to be left 115 * in plaintext for scrubbing and claiming, but the bonus buffers might contain 116 * sensitive user data. The function zio_crypt_init_uios_dnode() handles parsing 117 * which which pieces of the block need to be encrypted. For more details about 118 * dnode authentication and encryption, see zio_crypt_init_uios_dnode(). 119 * 120 * OBJECT SET AUTHENTICATION: 121 * Up to this point, everything we have encrypted and authenticated has been 122 * at level 0 (or -2 for the ZIL). If we did not do any further work the 123 * on-disk format would be susceptible to attacks that deleted or rearranged 124 * the order of level 0 blocks. Ideally, the cleanest solution would be to 125 * maintain a tree of authentication MACs going up the bp tree. However, this 126 * presents a problem for raw sends. Send files do not send information about 127 * indirect blocks so there would be no convenient way to transfer the MACs and 128 * they cannot be recalculated on the receive side without the master key which 129 * would defeat one of the purposes of raw sends in the first place. Instead, 130 * for the indirect levels of the bp tree, we use a regular SHA512 of the MACs 131 * from the level below. We also include some portable fields from blk_prop such 132 * as the lsize and compression algorithm to prevent the data from being 133 * misinterpreted. 134 * 135 * At the objset level, we maintain 2 separate 256 bit MACs in the 136 * objset_phys_t. The first one is "portable" and is the logical root of the 137 * MAC tree maintained in the metadnode's bps. The second, is "local" and is 138 * used as the root MAC for the user accounting objects, which are also not 139 * transferred via "zfs send". The portable MAC is sent in the DRR_BEGIN payload 140 * of the send file. The useraccounting code ensures that the useraccounting 141 * info is not present upon a receive, so the local MAC can simply be cleared 142 * out at that time. For more info about objset_phys_t authentication, see 143 * zio_crypt_do_objset_hmacs(). 144 * 145 * CONSIDERATIONS FOR DEDUP: 146 * In order for dedup to work, blocks that we want to dedup with one another 147 * need to use the same IV and encryption key, so that they will have the same 148 * ciphertext. Normally, one should never reuse an IV with the same encryption 149 * key or else AES-GCM and AES-CCM can both actually leak the plaintext of both 150 * blocks. In this case, however, since we are using the same plaintext as 151 * well all that we end up with is a duplicate of the original ciphertext we 152 * already had. As a result, an attacker with read access to the raw disk will 153 * be able to tell which blocks are the same but this information is given away 154 * by dedup anyway. In order to get the same IVs and encryption keys for 155 * equivalent blocks of data we use an HMAC of the plaintext. We use an HMAC 156 * here so that a reproducible checksum of the plaintext is never available to 157 * the attacker. The HMAC key is kept alongside the master key, encrypted on 158 * disk. The first 64 bits of the HMAC are used in place of the random salt, and 159 * the next 96 bits are used as the IV. As a result of this mechanism, dedup 160 * will only work within a clone family since encrypted dedup requires use of 161 * the same master and HMAC keys. 162 */ 163 164 /* 165 * After encrypting many blocks with the same key we may start to run up 166 * against the theoretical limits of how much data can securely be encrypted 167 * with a single key using the supported encryption modes. The most obvious 168 * limitation is that our risk of generating 2 equivalent 96 bit IVs increases 169 * the more IVs we generate (which both GCM and CCM modes strictly forbid). 170 * This risk actually grows surprisingly quickly over time according to the 171 * Birthday Problem. With a total IV space of 2^(96 bits), and assuming we have 172 * generated n IVs with a cryptographically secure RNG, the approximate 173 * probability p(n) of a collision is given as: 174 * 175 * p(n) ~= e^(-n*(n-1)/(2*(2^96))) 176 * 177 * [http://www.math.cornell.edu/~mec/2008-2009/TianyiZheng/Birthday.html] 178 * 179 * Assuming that we want to ensure that p(n) never goes over 1 / 1 trillion 180 * we must not write more than 398,065,730 blocks with the same encryption key. 181 * Therefore, we rotate our keys after 400,000,000 blocks have been written by 182 * generating a new random 64 bit salt for our HKDF encryption key generation 183 * function. 184 */ 185 #define ZFS_KEY_MAX_SALT_USES_DEFAULT 400000000 186 #define ZFS_CURRENT_MAX_SALT_USES \ 187 (MIN(zfs_key_max_salt_uses, ZFS_KEY_MAX_SALT_USES_DEFAULT)) 188 unsigned long zfs_key_max_salt_uses = ZFS_KEY_MAX_SALT_USES_DEFAULT; 189 190 /* 191 * Set to a nonzero value to cause zio_do_crypt_uio() to fail 1/this many 192 * calls, to test decryption error handling code paths. 193 */ 194 uint64_t zio_decrypt_fail_fraction = 0; 195 196 typedef struct blkptr_auth_buf { 197 uint64_t bab_prop; /* blk_prop - portable mask */ 198 uint8_t bab_mac[ZIO_DATA_MAC_LEN]; /* MAC from blk_cksum */ 199 uint64_t bab_pad; /* reserved for future use */ 200 } blkptr_auth_buf_t; 201 202 zio_crypt_info_t zio_crypt_table[ZIO_CRYPT_FUNCTIONS] = { 203 {"", ZC_TYPE_NONE, 0, "inherit"}, 204 {"", ZC_TYPE_NONE, 0, "on"}, 205 {"", ZC_TYPE_NONE, 0, "off"}, 206 {SUN_CKM_AES_CCM, ZC_TYPE_CCM, 16, "aes-128-ccm"}, 207 {SUN_CKM_AES_CCM, ZC_TYPE_CCM, 24, "aes-192-ccm"}, 208 {SUN_CKM_AES_CCM, ZC_TYPE_CCM, 32, "aes-256-ccm"}, 209 {SUN_CKM_AES_GCM, ZC_TYPE_GCM, 16, "aes-128-gcm"}, 210 {SUN_CKM_AES_GCM, ZC_TYPE_GCM, 24, "aes-192-gcm"}, 211 {SUN_CKM_AES_GCM, ZC_TYPE_GCM, 32, "aes-256-gcm"} 212 }; 213 214 static void 215 zio_crypt_key_destroy_early(zio_crypt_key_t *key) 216 { 217 rw_destroy(&key->zk_salt_lock); 218 219 /* free crypto templates */ 220 bzero(&key->zk_session, sizeof (key->zk_session)); 221 222 /* zero out sensitive data */ 223 bzero(key, sizeof (zio_crypt_key_t)); 224 } 225 226 void 227 zio_crypt_key_destroy(zio_crypt_key_t *key) 228 { 229 230 freebsd_crypt_freesession(&key->zk_session); 231 zio_crypt_key_destroy_early(key); 232 } 233 234 int 235 zio_crypt_key_init(uint64_t crypt, zio_crypt_key_t *key) 236 { 237 int ret; 238 crypto_mechanism_t mech __unused; 239 uint_t keydata_len; 240 zio_crypt_info_t *ci = NULL; 241 242 ASSERT(key != NULL); 243 ASSERT3U(crypt, <, ZIO_CRYPT_FUNCTIONS); 244 245 ci = &zio_crypt_table[crypt]; 246 if (ci->ci_crypt_type != ZC_TYPE_GCM && 247 ci->ci_crypt_type != ZC_TYPE_CCM) 248 return (ENOTSUP); 249 250 keydata_len = zio_crypt_table[crypt].ci_keylen; 251 bzero(key, sizeof (zio_crypt_key_t)); 252 rw_init(&key->zk_salt_lock, NULL, RW_DEFAULT, NULL); 253 254 /* fill keydata buffers and salt with random data */ 255 ret = random_get_bytes((uint8_t *)&key->zk_guid, sizeof (uint64_t)); 256 if (ret != 0) 257 goto error; 258 259 ret = random_get_bytes(key->zk_master_keydata, keydata_len); 260 if (ret != 0) 261 goto error; 262 263 ret = random_get_bytes(key->zk_hmac_keydata, SHA512_HMAC_KEYLEN); 264 if (ret != 0) 265 goto error; 266 267 ret = random_get_bytes(key->zk_salt, ZIO_DATA_SALT_LEN); 268 if (ret != 0) 269 goto error; 270 271 /* derive the current key from the master key */ 272 ret = hkdf_sha512(key->zk_master_keydata, keydata_len, NULL, 0, 273 key->zk_salt, ZIO_DATA_SALT_LEN, key->zk_current_keydata, 274 keydata_len); 275 if (ret != 0) 276 goto error; 277 278 /* initialize keys for the ICP */ 279 key->zk_current_key.ck_format = CRYPTO_KEY_RAW; 280 key->zk_current_key.ck_data = key->zk_current_keydata; 281 key->zk_current_key.ck_length = CRYPTO_BYTES2BITS(keydata_len); 282 283 key->zk_hmac_key.ck_format = CRYPTO_KEY_RAW; 284 key->zk_hmac_key.ck_data = &key->zk_hmac_key; 285 key->zk_hmac_key.ck_length = CRYPTO_BYTES2BITS(SHA512_HMAC_KEYLEN); 286 287 ci = &zio_crypt_table[crypt]; 288 if (ci->ci_crypt_type != ZC_TYPE_GCM && 289 ci->ci_crypt_type != ZC_TYPE_CCM) 290 return (ENOTSUP); 291 292 ret = freebsd_crypt_newsession(&key->zk_session, ci, 293 &key->zk_current_key); 294 if (ret) 295 goto error; 296 297 key->zk_crypt = crypt; 298 key->zk_version = ZIO_CRYPT_KEY_CURRENT_VERSION; 299 key->zk_salt_count = 0; 300 301 return (0); 302 303 error: 304 zio_crypt_key_destroy_early(key); 305 return (ret); 306 } 307 308 static int 309 zio_crypt_key_change_salt(zio_crypt_key_t *key) 310 { 311 int ret = 0; 312 uint8_t salt[ZIO_DATA_SALT_LEN]; 313 crypto_mechanism_t mech __unused; 314 315 uint_t keydata_len = zio_crypt_table[key->zk_crypt].ci_keylen; 316 317 /* generate a new salt */ 318 ret = random_get_bytes(salt, ZIO_DATA_SALT_LEN); 319 if (ret != 0) 320 goto error; 321 322 rw_enter(&key->zk_salt_lock, RW_WRITER); 323 324 /* someone beat us to the salt rotation, just unlock and return */ 325 if (key->zk_salt_count < ZFS_CURRENT_MAX_SALT_USES) 326 goto out_unlock; 327 328 /* derive the current key from the master key and the new salt */ 329 ret = hkdf_sha512(key->zk_master_keydata, keydata_len, NULL, 0, 330 salt, ZIO_DATA_SALT_LEN, key->zk_current_keydata, keydata_len); 331 if (ret != 0) 332 goto out_unlock; 333 334 /* assign the salt and reset the usage count */ 335 bcopy(salt, key->zk_salt, ZIO_DATA_SALT_LEN); 336 key->zk_salt_count = 0; 337 338 freebsd_crypt_freesession(&key->zk_session); 339 ret = freebsd_crypt_newsession(&key->zk_session, 340 &zio_crypt_table[key->zk_crypt], &key->zk_current_key); 341 if (ret != 0) 342 goto out_unlock; 343 344 rw_exit(&key->zk_salt_lock); 345 346 return (0); 347 348 out_unlock: 349 rw_exit(&key->zk_salt_lock); 350 error: 351 return (ret); 352 } 353 354 /* See comment above zfs_key_max_salt_uses definition for details */ 355 int 356 zio_crypt_key_get_salt(zio_crypt_key_t *key, uint8_t *salt) 357 { 358 int ret; 359 boolean_t salt_change; 360 361 rw_enter(&key->zk_salt_lock, RW_READER); 362 363 bcopy(key->zk_salt, salt, ZIO_DATA_SALT_LEN); 364 salt_change = (atomic_inc_64_nv(&key->zk_salt_count) >= 365 ZFS_CURRENT_MAX_SALT_USES); 366 367 rw_exit(&key->zk_salt_lock); 368 369 if (salt_change) { 370 ret = zio_crypt_key_change_salt(key); 371 if (ret != 0) 372 goto error; 373 } 374 375 return (0); 376 377 error: 378 return (ret); 379 } 380 381 void *failed_decrypt_buf; 382 int failed_decrypt_size; 383 384 /* 385 * This function handles all encryption and decryption in zfs. When 386 * encrypting it expects puio to reference the plaintext and cuio to 387 * reference the ciphertext. cuio must have enough space for the 388 * ciphertext + room for a MAC. datalen should be the length of the 389 * plaintext / ciphertext alone. 390 */ 391 /* 392 * The implementation for FreeBSD's OpenCrypto. 393 * 394 * The big difference between ICP and FOC is that FOC uses a single 395 * buffer for input and output. This means that (for AES-GCM, the 396 * only one supported right now) the source must be copied into the 397 * destination, and the destination must have the AAD, and the tag/MAC, 398 * already associated with it. (Both implementations can use a uio.) 399 * 400 * Since the auth data is part of the iovec array, all we need to know 401 * is the length: 0 means there's no AAD. 402 * 403 */ 404 static int 405 zio_do_crypt_uio_opencrypto(boolean_t encrypt, freebsd_crypt_session_t *sess, 406 uint64_t crypt, crypto_key_t *key, uint8_t *ivbuf, uint_t datalen, 407 uio_t *uio, uint_t auth_len) 408 { 409 zio_crypt_info_t *ci; 410 int ret; 411 412 ci = &zio_crypt_table[crypt]; 413 if (ci->ci_crypt_type != ZC_TYPE_GCM && 414 ci->ci_crypt_type != ZC_TYPE_CCM) 415 return (ENOTSUP); 416 417 418 ret = freebsd_crypt_uio(encrypt, sess, ci, uio, key, ivbuf, 419 datalen, auth_len); 420 if (ret != 0) { 421 #ifdef FCRYPTO_DEBUG 422 printf("%s(%d): Returning error %s\n", 423 __FUNCTION__, __LINE__, encrypt ? "EIO" : "ECKSUM"); 424 #endif 425 ret = SET_ERROR(encrypt ? EIO : ECKSUM); 426 } 427 428 return (ret); 429 } 430 431 int 432 zio_crypt_key_wrap(crypto_key_t *cwkey, zio_crypt_key_t *key, uint8_t *iv, 433 uint8_t *mac, uint8_t *keydata_out, uint8_t *hmac_keydata_out) 434 { 435 int ret; 436 uint64_t aad[3]; 437 /* 438 * With OpenCrypto in FreeBSD, the same buffer is used for 439 * input and output. Also, the AAD (for AES-GMC at least) 440 * needs to logically go in front. 441 */ 442 uio_t cuio; 443 iovec_t iovecs[4]; 444 uint64_t crypt = key->zk_crypt; 445 uint_t enc_len, keydata_len, aad_len; 446 447 ASSERT3U(crypt, <, ZIO_CRYPT_FUNCTIONS); 448 ASSERT3U(cwkey->ck_format, ==, CRYPTO_KEY_RAW); 449 450 keydata_len = zio_crypt_table[crypt].ci_keylen; 451 452 /* generate iv for wrapping the master and hmac key */ 453 ret = random_get_pseudo_bytes(iv, WRAPPING_IV_LEN); 454 if (ret != 0) 455 goto error; 456 457 /* 458 * Since we only support one buffer, we need to copy 459 * the plain text (source) to the cipher buffer (dest). 460 * We set iovecs[0] -- the authentication data -- below. 461 */ 462 bcopy((void*)key->zk_master_keydata, keydata_out, keydata_len); 463 bcopy((void*)key->zk_hmac_keydata, hmac_keydata_out, 464 SHA512_HMAC_KEYLEN); 465 iovecs[1].iov_base = keydata_out; 466 iovecs[1].iov_len = keydata_len; 467 iovecs[2].iov_base = hmac_keydata_out; 468 iovecs[2].iov_len = SHA512_HMAC_KEYLEN; 469 iovecs[3].iov_base = mac; 470 iovecs[3].iov_len = WRAPPING_MAC_LEN; 471 472 /* 473 * Although we don't support writing to the old format, we do 474 * support rewrapping the key so that the user can move and 475 * quarantine datasets on the old format. 476 */ 477 if (key->zk_version == 0) { 478 aad_len = sizeof (uint64_t); 479 aad[0] = LE_64(key->zk_guid); 480 } else { 481 ASSERT3U(key->zk_version, ==, ZIO_CRYPT_KEY_CURRENT_VERSION); 482 aad_len = sizeof (uint64_t) * 3; 483 aad[0] = LE_64(key->zk_guid); 484 aad[1] = LE_64(crypt); 485 aad[2] = LE_64(key->zk_version); 486 } 487 488 iovecs[0].iov_base = aad; 489 iovecs[0].iov_len = aad_len; 490 enc_len = zio_crypt_table[crypt].ci_keylen + SHA512_HMAC_KEYLEN; 491 492 cuio.uio_iov = iovecs; 493 cuio.uio_iovcnt = 4; 494 cuio.uio_segflg = UIO_SYSSPACE; 495 496 /* encrypt the keys and store the resulting ciphertext and mac */ 497 ret = zio_do_crypt_uio_opencrypto(B_TRUE, NULL, crypt, cwkey, 498 iv, enc_len, &cuio, aad_len); 499 if (ret != 0) 500 goto error; 501 502 return (0); 503 504 error: 505 return (ret); 506 } 507 508 int 509 zio_crypt_key_unwrap(crypto_key_t *cwkey, uint64_t crypt, uint64_t version, 510 uint64_t guid, uint8_t *keydata, uint8_t *hmac_keydata, uint8_t *iv, 511 uint8_t *mac, zio_crypt_key_t *key) 512 { 513 int ret; 514 uint64_t aad[3]; 515 /* 516 * With OpenCrypto in FreeBSD, the same buffer is used for 517 * input and output. Also, the AAD (for AES-GMC at least) 518 * needs to logically go in front. 519 */ 520 uio_t cuio; 521 iovec_t iovecs[4]; 522 void *src, *dst; 523 uint_t enc_len, keydata_len, aad_len; 524 525 ASSERT3U(crypt, <, ZIO_CRYPT_FUNCTIONS); 526 ASSERT3U(cwkey->ck_format, ==, CRYPTO_KEY_RAW); 527 528 keydata_len = zio_crypt_table[crypt].ci_keylen; 529 rw_init(&key->zk_salt_lock, NULL, RW_DEFAULT, NULL); 530 531 /* 532 * Since we only support one buffer, we need to copy 533 * the encrypted buffer (source) to the plain buffer 534 * (dest). We set iovecs[0] -- the authentication data -- 535 * below. 536 */ 537 dst = key->zk_master_keydata; 538 src = keydata; 539 540 bcopy(src, dst, keydata_len); 541 542 dst = key->zk_hmac_keydata; 543 src = hmac_keydata; 544 bcopy(src, dst, SHA512_HMAC_KEYLEN); 545 546 iovecs[1].iov_base = key->zk_master_keydata; 547 iovecs[1].iov_len = keydata_len; 548 iovecs[2].iov_base = key->zk_hmac_keydata; 549 iovecs[2].iov_len = SHA512_HMAC_KEYLEN; 550 iovecs[3].iov_base = mac; 551 iovecs[3].iov_len = WRAPPING_MAC_LEN; 552 553 if (version == 0) { 554 aad_len = sizeof (uint64_t); 555 aad[0] = LE_64(guid); 556 } else { 557 ASSERT3U(version, ==, ZIO_CRYPT_KEY_CURRENT_VERSION); 558 aad_len = sizeof (uint64_t) * 3; 559 aad[0] = LE_64(guid); 560 aad[1] = LE_64(crypt); 561 aad[2] = LE_64(version); 562 } 563 564 enc_len = keydata_len + SHA512_HMAC_KEYLEN; 565 iovecs[0].iov_base = aad; 566 iovecs[0].iov_len = aad_len; 567 568 cuio.uio_iov = iovecs; 569 cuio.uio_iovcnt = 4; 570 cuio.uio_segflg = UIO_SYSSPACE; 571 572 /* decrypt the keys and store the result in the output buffers */ 573 ret = zio_do_crypt_uio_opencrypto(B_FALSE, NULL, crypt, cwkey, 574 iv, enc_len, &cuio, aad_len); 575 576 if (ret != 0) 577 goto error; 578 579 /* generate a fresh salt */ 580 ret = random_get_bytes(key->zk_salt, ZIO_DATA_SALT_LEN); 581 if (ret != 0) 582 goto error; 583 584 /* derive the current key from the master key */ 585 ret = hkdf_sha512(key->zk_master_keydata, keydata_len, NULL, 0, 586 key->zk_salt, ZIO_DATA_SALT_LEN, key->zk_current_keydata, 587 keydata_len); 588 if (ret != 0) 589 goto error; 590 591 /* initialize keys for ICP */ 592 key->zk_current_key.ck_format = CRYPTO_KEY_RAW; 593 key->zk_current_key.ck_data = key->zk_current_keydata; 594 key->zk_current_key.ck_length = CRYPTO_BYTES2BITS(keydata_len); 595 596 key->zk_hmac_key.ck_format = CRYPTO_KEY_RAW; 597 key->zk_hmac_key.ck_data = key->zk_hmac_keydata; 598 key->zk_hmac_key.ck_length = CRYPTO_BYTES2BITS(SHA512_HMAC_KEYLEN); 599 600 ret = freebsd_crypt_newsession(&key->zk_session, 601 &zio_crypt_table[crypt], &key->zk_current_key); 602 if (ret != 0) 603 goto error; 604 605 key->zk_crypt = crypt; 606 key->zk_version = version; 607 key->zk_guid = guid; 608 key->zk_salt_count = 0; 609 610 return (0); 611 612 error: 613 zio_crypt_key_destroy_early(key); 614 return (ret); 615 } 616 617 int 618 zio_crypt_generate_iv(uint8_t *ivbuf) 619 { 620 int ret; 621 622 /* randomly generate the IV */ 623 ret = random_get_pseudo_bytes(ivbuf, ZIO_DATA_IV_LEN); 624 if (ret != 0) 625 goto error; 626 627 return (0); 628 629 error: 630 bzero(ivbuf, ZIO_DATA_IV_LEN); 631 return (ret); 632 } 633 634 int 635 zio_crypt_do_hmac(zio_crypt_key_t *key, uint8_t *data, uint_t datalen, 636 uint8_t *digestbuf, uint_t digestlen) 637 { 638 uint8_t raw_digestbuf[SHA512_DIGEST_LENGTH]; 639 640 ASSERT3U(digestlen, <=, SHA512_DIGEST_LENGTH); 641 642 crypto_mac(&key->zk_hmac_key, data, datalen, 643 raw_digestbuf, SHA512_DIGEST_LENGTH); 644 645 bcopy(raw_digestbuf, digestbuf, digestlen); 646 647 return (0); 648 } 649 650 int 651 zio_crypt_generate_iv_salt_dedup(zio_crypt_key_t *key, uint8_t *data, 652 uint_t datalen, uint8_t *ivbuf, uint8_t *salt) 653 { 654 int ret; 655 uint8_t digestbuf[SHA512_DIGEST_LENGTH]; 656 657 ret = zio_crypt_do_hmac(key, data, datalen, 658 digestbuf, SHA512_DIGEST_LENGTH); 659 if (ret != 0) 660 return (ret); 661 662 bcopy(digestbuf, salt, ZIO_DATA_SALT_LEN); 663 bcopy(digestbuf + ZIO_DATA_SALT_LEN, ivbuf, ZIO_DATA_IV_LEN); 664 665 return (0); 666 } 667 668 /* 669 * The following functions are used to encode and decode encryption parameters 670 * into blkptr_t and zil_header_t. The ICP wants to use these parameters as 671 * byte strings, which normally means that these strings would not need to deal 672 * with byteswapping at all. However, both blkptr_t and zil_header_t may be 673 * byteswapped by lower layers and so we must "undo" that byteswap here upon 674 * decoding and encoding in a non-native byteorder. These functions require 675 * that the byteorder bit is correct before being called. 676 */ 677 void 678 zio_crypt_encode_params_bp(blkptr_t *bp, uint8_t *salt, uint8_t *iv) 679 { 680 uint64_t val64; 681 uint32_t val32; 682 683 ASSERT(BP_IS_ENCRYPTED(bp)); 684 685 if (!BP_SHOULD_BYTESWAP(bp)) { 686 bcopy(salt, &bp->blk_dva[2].dva_word[0], sizeof (uint64_t)); 687 bcopy(iv, &bp->blk_dva[2].dva_word[1], sizeof (uint64_t)); 688 bcopy(iv + sizeof (uint64_t), &val32, sizeof (uint32_t)); 689 BP_SET_IV2(bp, val32); 690 } else { 691 bcopy(salt, &val64, sizeof (uint64_t)); 692 bp->blk_dva[2].dva_word[0] = BSWAP_64(val64); 693 694 bcopy(iv, &val64, sizeof (uint64_t)); 695 bp->blk_dva[2].dva_word[1] = BSWAP_64(val64); 696 697 bcopy(iv + sizeof (uint64_t), &val32, sizeof (uint32_t)); 698 BP_SET_IV2(bp, BSWAP_32(val32)); 699 } 700 } 701 702 void 703 zio_crypt_decode_params_bp(const blkptr_t *bp, uint8_t *salt, uint8_t *iv) 704 { 705 uint64_t val64; 706 uint32_t val32; 707 708 ASSERT(BP_IS_PROTECTED(bp)); 709 710 /* for convenience, so callers don't need to check */ 711 if (BP_IS_AUTHENTICATED(bp)) { 712 bzero(salt, ZIO_DATA_SALT_LEN); 713 bzero(iv, ZIO_DATA_IV_LEN); 714 return; 715 } 716 717 if (!BP_SHOULD_BYTESWAP(bp)) { 718 bcopy(&bp->blk_dva[2].dva_word[0], salt, sizeof (uint64_t)); 719 bcopy(&bp->blk_dva[2].dva_word[1], iv, sizeof (uint64_t)); 720 721 val32 = (uint32_t)BP_GET_IV2(bp); 722 bcopy(&val32, iv + sizeof (uint64_t), sizeof (uint32_t)); 723 } else { 724 val64 = BSWAP_64(bp->blk_dva[2].dva_word[0]); 725 bcopy(&val64, salt, sizeof (uint64_t)); 726 727 val64 = BSWAP_64(bp->blk_dva[2].dva_word[1]); 728 bcopy(&val64, iv, sizeof (uint64_t)); 729 730 val32 = BSWAP_32((uint32_t)BP_GET_IV2(bp)); 731 bcopy(&val32, iv + sizeof (uint64_t), sizeof (uint32_t)); 732 } 733 } 734 735 void 736 zio_crypt_encode_mac_bp(blkptr_t *bp, uint8_t *mac) 737 { 738 uint64_t val64; 739 740 ASSERT(BP_USES_CRYPT(bp)); 741 ASSERT3U(BP_GET_TYPE(bp), !=, DMU_OT_OBJSET); 742 743 if (!BP_SHOULD_BYTESWAP(bp)) { 744 bcopy(mac, &bp->blk_cksum.zc_word[2], sizeof (uint64_t)); 745 bcopy(mac + sizeof (uint64_t), &bp->blk_cksum.zc_word[3], 746 sizeof (uint64_t)); 747 } else { 748 bcopy(mac, &val64, sizeof (uint64_t)); 749 bp->blk_cksum.zc_word[2] = BSWAP_64(val64); 750 751 bcopy(mac + sizeof (uint64_t), &val64, sizeof (uint64_t)); 752 bp->blk_cksum.zc_word[3] = BSWAP_64(val64); 753 } 754 } 755 756 void 757 zio_crypt_decode_mac_bp(const blkptr_t *bp, uint8_t *mac) 758 { 759 uint64_t val64; 760 761 ASSERT(BP_USES_CRYPT(bp) || BP_IS_HOLE(bp)); 762 763 /* for convenience, so callers don't need to check */ 764 if (BP_GET_TYPE(bp) == DMU_OT_OBJSET) { 765 bzero(mac, ZIO_DATA_MAC_LEN); 766 return; 767 } 768 769 if (!BP_SHOULD_BYTESWAP(bp)) { 770 bcopy(&bp->blk_cksum.zc_word[2], mac, sizeof (uint64_t)); 771 bcopy(&bp->blk_cksum.zc_word[3], mac + sizeof (uint64_t), 772 sizeof (uint64_t)); 773 } else { 774 val64 = BSWAP_64(bp->blk_cksum.zc_word[2]); 775 bcopy(&val64, mac, sizeof (uint64_t)); 776 777 val64 = BSWAP_64(bp->blk_cksum.zc_word[3]); 778 bcopy(&val64, mac + sizeof (uint64_t), sizeof (uint64_t)); 779 } 780 } 781 782 void 783 zio_crypt_encode_mac_zil(void *data, uint8_t *mac) 784 { 785 zil_chain_t *zilc = data; 786 787 bcopy(mac, &zilc->zc_eck.zec_cksum.zc_word[2], sizeof (uint64_t)); 788 bcopy(mac + sizeof (uint64_t), &zilc->zc_eck.zec_cksum.zc_word[3], 789 sizeof (uint64_t)); 790 } 791 792 void 793 zio_crypt_decode_mac_zil(const void *data, uint8_t *mac) 794 { 795 /* 796 * The ZIL MAC is embedded in the block it protects, which will 797 * not have been byteswapped by the time this function has been called. 798 * As a result, we don't need to worry about byteswapping the MAC. 799 */ 800 const zil_chain_t *zilc = data; 801 802 bcopy(&zilc->zc_eck.zec_cksum.zc_word[2], mac, sizeof (uint64_t)); 803 bcopy(&zilc->zc_eck.zec_cksum.zc_word[3], mac + sizeof (uint64_t), 804 sizeof (uint64_t)); 805 } 806 807 /* 808 * This routine takes a block of dnodes (src_abd) and copies only the bonus 809 * buffers to the same offsets in the dst buffer. datalen should be the size 810 * of both the src_abd and the dst buffer (not just the length of the bonus 811 * buffers). 812 */ 813 void 814 zio_crypt_copy_dnode_bonus(abd_t *src_abd, uint8_t *dst, uint_t datalen) 815 { 816 uint_t i, max_dnp = datalen >> DNODE_SHIFT; 817 uint8_t *src; 818 dnode_phys_t *dnp, *sdnp, *ddnp; 819 820 src = abd_borrow_buf_copy(src_abd, datalen); 821 822 sdnp = (dnode_phys_t *)src; 823 ddnp = (dnode_phys_t *)dst; 824 825 for (i = 0; i < max_dnp; i += sdnp[i].dn_extra_slots + 1) { 826 dnp = &sdnp[i]; 827 if (dnp->dn_type != DMU_OT_NONE && 828 DMU_OT_IS_ENCRYPTED(dnp->dn_bonustype) && 829 dnp->dn_bonuslen != 0) { 830 bcopy(DN_BONUS(dnp), DN_BONUS(&ddnp[i]), 831 DN_MAX_BONUS_LEN(dnp)); 832 } 833 } 834 835 abd_return_buf(src_abd, src, datalen); 836 } 837 838 /* 839 * This function decides what fields from blk_prop are included in 840 * the on-disk various MAC algorithms. 841 */ 842 static void 843 zio_crypt_bp_zero_nonportable_blkprop(blkptr_t *bp, uint64_t version) 844 { 845 int avoidlint = SPA_MINBLOCKSIZE; 846 /* 847 * Version 0 did not properly zero out all non-portable fields 848 * as it should have done. We maintain this code so that we can 849 * do read-only imports of pools on this version. 850 */ 851 if (version == 0) { 852 BP_SET_DEDUP(bp, 0); 853 BP_SET_CHECKSUM(bp, 0); 854 BP_SET_PSIZE(bp, avoidlint); 855 return; 856 } 857 858 ASSERT3U(version, ==, ZIO_CRYPT_KEY_CURRENT_VERSION); 859 860 /* 861 * The hole_birth feature might set these fields even if this bp 862 * is a hole. We zero them out here to guarantee that raw sends 863 * will function with or without the feature. 864 */ 865 if (BP_IS_HOLE(bp)) { 866 bp->blk_prop = 0ULL; 867 return; 868 } 869 870 /* 871 * At L0 we want to verify these fields to ensure that data blocks 872 * can not be reinterpreted. For instance, we do not want an attacker 873 * to trick us into returning raw lz4 compressed data to the user 874 * by modifying the compression bits. At higher levels, we cannot 875 * enforce this policy since raw sends do not convey any information 876 * about indirect blocks, so these values might be different on the 877 * receive side. Fortunately, this does not open any new attack 878 * vectors, since any alterations that can be made to a higher level 879 * bp must still verify the correct order of the layer below it. 880 */ 881 if (BP_GET_LEVEL(bp) != 0) { 882 BP_SET_BYTEORDER(bp, 0); 883 BP_SET_COMPRESS(bp, 0); 884 885 /* 886 * psize cannot be set to zero or it will trigger 887 * asserts, but the value doesn't really matter as 888 * long as it is constant. 889 */ 890 BP_SET_PSIZE(bp, avoidlint); 891 } 892 893 BP_SET_DEDUP(bp, 0); 894 BP_SET_CHECKSUM(bp, 0); 895 } 896 897 static void 898 zio_crypt_bp_auth_init(uint64_t version, boolean_t should_bswap, blkptr_t *bp, 899 blkptr_auth_buf_t *bab, uint_t *bab_len) 900 { 901 blkptr_t tmpbp = *bp; 902 903 if (should_bswap) 904 byteswap_uint64_array(&tmpbp, sizeof (blkptr_t)); 905 906 ASSERT(BP_USES_CRYPT(&tmpbp) || BP_IS_HOLE(&tmpbp)); 907 ASSERT0(BP_IS_EMBEDDED(&tmpbp)); 908 909 zio_crypt_decode_mac_bp(&tmpbp, bab->bab_mac); 910 911 /* 912 * We always MAC blk_prop in LE to ensure portability. This 913 * must be done after decoding the mac, since the endianness 914 * will get zero'd out here. 915 */ 916 zio_crypt_bp_zero_nonportable_blkprop(&tmpbp, version); 917 bab->bab_prop = LE_64(tmpbp.blk_prop); 918 bab->bab_pad = 0ULL; 919 920 /* version 0 did not include the padding */ 921 *bab_len = sizeof (blkptr_auth_buf_t); 922 if (version == 0) 923 *bab_len -= sizeof (uint64_t); 924 } 925 926 static int 927 zio_crypt_bp_do_hmac_updates(crypto_context_t ctx, uint64_t version, 928 boolean_t should_bswap, blkptr_t *bp) 929 { 930 uint_t bab_len; 931 blkptr_auth_buf_t bab; 932 933 zio_crypt_bp_auth_init(version, should_bswap, bp, &bab, &bab_len); 934 crypto_mac_update(ctx, &bab, bab_len); 935 936 return (0); 937 } 938 939 static void 940 zio_crypt_bp_do_indrect_checksum_updates(SHA2_CTX *ctx, uint64_t version, 941 boolean_t should_bswap, blkptr_t *bp) 942 { 943 uint_t bab_len; 944 blkptr_auth_buf_t bab; 945 946 zio_crypt_bp_auth_init(version, should_bswap, bp, &bab, &bab_len); 947 SHA2Update(ctx, &bab, bab_len); 948 } 949 950 static void 951 zio_crypt_bp_do_aad_updates(uint8_t **aadp, uint_t *aad_len, uint64_t version, 952 boolean_t should_bswap, blkptr_t *bp) 953 { 954 uint_t bab_len; 955 blkptr_auth_buf_t bab; 956 957 zio_crypt_bp_auth_init(version, should_bswap, bp, &bab, &bab_len); 958 bcopy(&bab, *aadp, bab_len); 959 *aadp += bab_len; 960 *aad_len += bab_len; 961 } 962 963 static int 964 zio_crypt_do_dnode_hmac_updates(crypto_context_t ctx, uint64_t version, 965 boolean_t should_bswap, dnode_phys_t *dnp) 966 { 967 int ret, i; 968 dnode_phys_t *adnp; 969 boolean_t le_bswap = (should_bswap == ZFS_HOST_BYTEORDER); 970 uint8_t tmp_dncore[offsetof(dnode_phys_t, dn_blkptr)]; 971 972 /* authenticate the core dnode (masking out non-portable bits) */ 973 bcopy(dnp, tmp_dncore, sizeof (tmp_dncore)); 974 adnp = (dnode_phys_t *)tmp_dncore; 975 if (le_bswap) { 976 adnp->dn_datablkszsec = BSWAP_16(adnp->dn_datablkszsec); 977 adnp->dn_bonuslen = BSWAP_16(adnp->dn_bonuslen); 978 adnp->dn_maxblkid = BSWAP_64(adnp->dn_maxblkid); 979 adnp->dn_used = BSWAP_64(adnp->dn_used); 980 } 981 adnp->dn_flags &= DNODE_CRYPT_PORTABLE_FLAGS_MASK; 982 adnp->dn_used = 0; 983 984 crypto_mac_update(ctx, adnp, sizeof (tmp_dncore)); 985 986 for (i = 0; i < dnp->dn_nblkptr; i++) { 987 ret = zio_crypt_bp_do_hmac_updates(ctx, version, 988 should_bswap, &dnp->dn_blkptr[i]); 989 if (ret != 0) 990 goto error; 991 } 992 993 if (dnp->dn_flags & DNODE_FLAG_SPILL_BLKPTR) { 994 ret = zio_crypt_bp_do_hmac_updates(ctx, version, 995 should_bswap, DN_SPILL_BLKPTR(dnp)); 996 if (ret != 0) 997 goto error; 998 } 999 1000 return (0); 1001 1002 error: 1003 return (ret); 1004 } 1005 1006 /* 1007 * objset_phys_t blocks introduce a number of exceptions to the normal 1008 * authentication process. objset_phys_t's contain 2 separate HMACS for 1009 * protecting the integrity of their data. The portable_mac protects the 1010 * metadnode. This MAC can be sent with a raw send and protects against 1011 * reordering of data within the metadnode. The local_mac protects the user 1012 * accounting objects which are not sent from one system to another. 1013 * 1014 * In addition, objset blocks are the only blocks that can be modified and 1015 * written to disk without the key loaded under certain circumstances. During 1016 * zil_claim() we need to be able to update the zil_header_t to complete 1017 * claiming log blocks and during raw receives we need to write out the 1018 * portable_mac from the send file. Both of these actions are possible 1019 * because these fields are not protected by either MAC so neither one will 1020 * need to modify the MACs without the key. However, when the modified blocks 1021 * are written out they will be byteswapped into the host machine's native 1022 * endianness which will modify fields protected by the MAC. As a result, MAC 1023 * calculation for objset blocks works slightly differently from other block 1024 * types. Where other block types MAC the data in whatever endianness is 1025 * written to disk, objset blocks always MAC little endian version of their 1026 * values. In the code, should_bswap is the value from BP_SHOULD_BYTESWAP() 1027 * and le_bswap indicates whether a byteswap is needed to get this block 1028 * into little endian format. 1029 */ 1030 /* ARGSUSED */ 1031 int 1032 zio_crypt_do_objset_hmacs(zio_crypt_key_t *key, void *data, uint_t datalen, 1033 boolean_t should_bswap, uint8_t *portable_mac, uint8_t *local_mac) 1034 { 1035 int ret; 1036 struct hmac_ctx hash_ctx; 1037 struct hmac_ctx *ctx = &hash_ctx; 1038 objset_phys_t *osp = data; 1039 uint64_t intval; 1040 boolean_t le_bswap = (should_bswap == ZFS_HOST_BYTEORDER); 1041 uint8_t raw_portable_mac[SHA512_DIGEST_LENGTH]; 1042 uint8_t raw_local_mac[SHA512_DIGEST_LENGTH]; 1043 1044 1045 /* calculate the portable MAC from the portable fields and metadnode */ 1046 crypto_mac_init(ctx, &key->zk_hmac_key); 1047 1048 /* add in the os_type */ 1049 intval = (le_bswap) ? osp->os_type : BSWAP_64(osp->os_type); 1050 crypto_mac_update(ctx, &intval, sizeof (uint64_t)); 1051 1052 /* add in the portable os_flags */ 1053 intval = osp->os_flags; 1054 if (should_bswap) 1055 intval = BSWAP_64(intval); 1056 intval &= OBJSET_CRYPT_PORTABLE_FLAGS_MASK; 1057 /* CONSTCOND */ 1058 if (!ZFS_HOST_BYTEORDER) 1059 intval = BSWAP_64(intval); 1060 1061 crypto_mac_update(ctx, &intval, sizeof (uint64_t)); 1062 1063 /* add in fields from the metadnode */ 1064 ret = zio_crypt_do_dnode_hmac_updates(ctx, key->zk_version, 1065 should_bswap, &osp->os_meta_dnode); 1066 if (ret) 1067 goto error; 1068 1069 crypto_mac_final(ctx, raw_portable_mac, SHA512_DIGEST_LENGTH); 1070 1071 bcopy(raw_portable_mac, portable_mac, ZIO_OBJSET_MAC_LEN); 1072 1073 /* 1074 * The local MAC protects the user, group and project accounting. 1075 * If these objects are not present, the local MAC is zeroed out. 1076 */ 1077 if ((datalen >= OBJSET_PHYS_SIZE_V3 && 1078 osp->os_userused_dnode.dn_type == DMU_OT_NONE && 1079 osp->os_groupused_dnode.dn_type == DMU_OT_NONE && 1080 osp->os_projectused_dnode.dn_type == DMU_OT_NONE) || 1081 (datalen >= OBJSET_PHYS_SIZE_V2 && 1082 osp->os_userused_dnode.dn_type == DMU_OT_NONE && 1083 osp->os_groupused_dnode.dn_type == DMU_OT_NONE) || 1084 (datalen <= OBJSET_PHYS_SIZE_V1)) { 1085 bzero(local_mac, ZIO_OBJSET_MAC_LEN); 1086 return (0); 1087 } 1088 1089 /* calculate the local MAC from the userused and groupused dnodes */ 1090 crypto_mac_init(ctx, &key->zk_hmac_key); 1091 1092 /* add in the non-portable os_flags */ 1093 intval = osp->os_flags; 1094 if (should_bswap) 1095 intval = BSWAP_64(intval); 1096 intval &= ~OBJSET_CRYPT_PORTABLE_FLAGS_MASK; 1097 /* CONSTCOND */ 1098 if (!ZFS_HOST_BYTEORDER) 1099 intval = BSWAP_64(intval); 1100 1101 crypto_mac_update(ctx, &intval, sizeof (uint64_t)); 1102 1103 /* XXX check dnode type ... */ 1104 /* add in fields from the user accounting dnodes */ 1105 if (osp->os_userused_dnode.dn_type != DMU_OT_NONE) { 1106 ret = zio_crypt_do_dnode_hmac_updates(ctx, key->zk_version, 1107 should_bswap, &osp->os_userused_dnode); 1108 if (ret) 1109 goto error; 1110 } 1111 1112 if (osp->os_groupused_dnode.dn_type != DMU_OT_NONE) { 1113 ret = zio_crypt_do_dnode_hmac_updates(ctx, key->zk_version, 1114 should_bswap, &osp->os_groupused_dnode); 1115 if (ret) 1116 goto error; 1117 } 1118 1119 if (osp->os_projectused_dnode.dn_type != DMU_OT_NONE && 1120 datalen >= OBJSET_PHYS_SIZE_V3) { 1121 ret = zio_crypt_do_dnode_hmac_updates(ctx, key->zk_version, 1122 should_bswap, &osp->os_projectused_dnode); 1123 if (ret) 1124 goto error; 1125 } 1126 1127 crypto_mac_final(ctx, raw_local_mac, SHA512_DIGEST_LENGTH); 1128 1129 bcopy(raw_local_mac, local_mac, ZIO_OBJSET_MAC_LEN); 1130 1131 return (0); 1132 1133 error: 1134 bzero(portable_mac, ZIO_OBJSET_MAC_LEN); 1135 bzero(local_mac, ZIO_OBJSET_MAC_LEN); 1136 return (ret); 1137 } 1138 1139 static void 1140 zio_crypt_destroy_uio(uio_t *uio) 1141 { 1142 if (uio->uio_iov) 1143 kmem_free(uio->uio_iov, uio->uio_iovcnt * sizeof (iovec_t)); 1144 } 1145 1146 /* 1147 * This function parses an uncompressed indirect block and returns a checksum 1148 * of all the portable fields from all of the contained bps. The portable 1149 * fields are the MAC and all of the fields from blk_prop except for the dedup, 1150 * checksum, and psize bits. For an explanation of the purpose of this, see 1151 * the comment block on object set authentication. 1152 */ 1153 static int 1154 zio_crypt_do_indirect_mac_checksum_impl(boolean_t generate, void *buf, 1155 uint_t datalen, uint64_t version, boolean_t byteswap, uint8_t *cksum) 1156 { 1157 blkptr_t *bp; 1158 int i, epb = datalen >> SPA_BLKPTRSHIFT; 1159 SHA2_CTX ctx; 1160 uint8_t digestbuf[SHA512_DIGEST_LENGTH]; 1161 1162 /* checksum all of the MACs from the layer below */ 1163 SHA2Init(SHA512, &ctx); 1164 for (i = 0, bp = buf; i < epb; i++, bp++) { 1165 zio_crypt_bp_do_indrect_checksum_updates(&ctx, version, 1166 byteswap, bp); 1167 } 1168 SHA2Final(digestbuf, &ctx); 1169 1170 if (generate) { 1171 bcopy(digestbuf, cksum, ZIO_DATA_MAC_LEN); 1172 return (0); 1173 } 1174 1175 if (bcmp(digestbuf, cksum, ZIO_DATA_MAC_LEN) != 0) { 1176 #ifdef FCRYPTO_DEBUG 1177 printf("%s(%d): Setting ECKSUM\n", __FUNCTION__, __LINE__); 1178 #endif 1179 return (SET_ERROR(ECKSUM)); 1180 } 1181 return (0); 1182 } 1183 1184 int 1185 zio_crypt_do_indirect_mac_checksum(boolean_t generate, void *buf, 1186 uint_t datalen, boolean_t byteswap, uint8_t *cksum) 1187 { 1188 int ret; 1189 1190 /* 1191 * Unfortunately, callers of this function will not always have 1192 * easy access to the on-disk format version. This info is 1193 * normally found in the DSL Crypto Key, but the checksum-of-MACs 1194 * is expected to be verifiable even when the key isn't loaded. 1195 * Here, instead of doing a ZAP lookup for the version for each 1196 * zio, we simply try both existing formats. 1197 */ 1198 ret = zio_crypt_do_indirect_mac_checksum_impl(generate, buf, 1199 datalen, ZIO_CRYPT_KEY_CURRENT_VERSION, byteswap, cksum); 1200 if (ret == ECKSUM) { 1201 ASSERT(!generate); 1202 ret = zio_crypt_do_indirect_mac_checksum_impl(generate, 1203 buf, datalen, 0, byteswap, cksum); 1204 } 1205 1206 return (ret); 1207 } 1208 1209 int 1210 zio_crypt_do_indirect_mac_checksum_abd(boolean_t generate, abd_t *abd, 1211 uint_t datalen, boolean_t byteswap, uint8_t *cksum) 1212 { 1213 int ret; 1214 void *buf; 1215 1216 buf = abd_borrow_buf_copy(abd, datalen); 1217 ret = zio_crypt_do_indirect_mac_checksum(generate, buf, datalen, 1218 byteswap, cksum); 1219 abd_return_buf(abd, buf, datalen); 1220 1221 return (ret); 1222 } 1223 1224 /* 1225 * Special case handling routine for encrypting / decrypting ZIL blocks. 1226 * We do not check for the older ZIL chain because the encryption feature 1227 * was not available before the newer ZIL chain was introduced. The goal 1228 * here is to encrypt everything except the blkptr_t of a lr_write_t and 1229 * the zil_chain_t header. Everything that is not encrypted is authenticated. 1230 */ 1231 /* 1232 * The OpenCrypto used in FreeBSD does not use separate source and 1233 * destination buffers; instead, the same buffer is used. Further, to 1234 * accommodate some of the drivers, the authbuf needs to be logically before 1235 * the data. This means that we need to copy the source to the destination, 1236 * and set up an extra iovec_t at the beginning to handle the authbuf. 1237 * It also means we'll only return one uio_t. 1238 */ 1239 1240 /* ARGSUSED */ 1241 static int 1242 zio_crypt_init_uios_zil(boolean_t encrypt, uint8_t *plainbuf, 1243 uint8_t *cipherbuf, uint_t datalen, boolean_t byteswap, uio_t *puio, 1244 uio_t *out_uio, uint_t *enc_len, uint8_t **authbuf, uint_t *auth_len, 1245 boolean_t *no_crypt) 1246 { 1247 uint8_t *aadbuf = zio_buf_alloc(datalen); 1248 uint8_t *src, *dst, *slrp, *dlrp, *blkend, *aadp; 1249 iovec_t *dst_iovecs; 1250 zil_chain_t *zilc; 1251 lr_t *lr; 1252 uint64_t txtype, lr_len; 1253 uint_t crypt_len, nr_iovecs, vec; 1254 uint_t aad_len = 0, total_len = 0; 1255 1256 if (encrypt) { 1257 src = plainbuf; 1258 dst = cipherbuf; 1259 } else { 1260 src = cipherbuf; 1261 dst = plainbuf; 1262 } 1263 bcopy(src, dst, datalen); 1264 1265 /* Find the start and end record of the log block. */ 1266 zilc = (zil_chain_t *)src; 1267 slrp = src + sizeof (zil_chain_t); 1268 aadp = aadbuf; 1269 blkend = src + ((byteswap) ? BSWAP_64(zilc->zc_nused) : zilc->zc_nused); 1270 1271 /* 1272 * Calculate the number of encrypted iovecs we will need. 1273 */ 1274 1275 /* We need at least two iovecs -- one for the AAD, one for the MAC. */ 1276 nr_iovecs = 2; 1277 1278 for (; slrp < blkend; slrp += lr_len) { 1279 lr = (lr_t *)slrp; 1280 1281 if (byteswap) { 1282 txtype = BSWAP_64(lr->lrc_txtype); 1283 lr_len = BSWAP_64(lr->lrc_reclen); 1284 } else { 1285 txtype = lr->lrc_txtype; 1286 lr_len = lr->lrc_reclen; 1287 } 1288 1289 nr_iovecs++; 1290 if (txtype == TX_WRITE && lr_len != sizeof (lr_write_t)) 1291 nr_iovecs++; 1292 } 1293 1294 dst_iovecs = kmem_alloc(nr_iovecs * sizeof (iovec_t), KM_SLEEP); 1295 1296 /* 1297 * Copy the plain zil header over and authenticate everything except 1298 * the checksum that will store our MAC. If we are writing the data 1299 * the embedded checksum will not have been calculated yet, so we don't 1300 * authenticate that. 1301 */ 1302 bcopy(src, aadp, sizeof (zil_chain_t) - sizeof (zio_eck_t)); 1303 aadp += sizeof (zil_chain_t) - sizeof (zio_eck_t); 1304 aad_len += sizeof (zil_chain_t) - sizeof (zio_eck_t); 1305 1306 slrp = src + sizeof (zil_chain_t); 1307 dlrp = dst + sizeof (zil_chain_t); 1308 1309 /* 1310 * Loop over records again, filling in iovecs. 1311 */ 1312 1313 /* The first iovec will contain the authbuf. */ 1314 vec = 1; 1315 1316 for (; slrp < blkend; slrp += lr_len, dlrp += lr_len) { 1317 lr = (lr_t *)slrp; 1318 1319 if (!byteswap) { 1320 txtype = lr->lrc_txtype; 1321 lr_len = lr->lrc_reclen; 1322 } else { 1323 txtype = BSWAP_64(lr->lrc_txtype); 1324 lr_len = BSWAP_64(lr->lrc_reclen); 1325 } 1326 1327 /* copy the common lr_t */ 1328 bcopy(slrp, dlrp, sizeof (lr_t)); 1329 bcopy(slrp, aadp, sizeof (lr_t)); 1330 aadp += sizeof (lr_t); 1331 aad_len += sizeof (lr_t); 1332 1333 /* 1334 * If this is a TX_WRITE record we want to encrypt everything 1335 * except the bp if exists. If the bp does exist we want to 1336 * authenticate it. 1337 */ 1338 if (txtype == TX_WRITE) { 1339 crypt_len = sizeof (lr_write_t) - 1340 sizeof (lr_t) - sizeof (blkptr_t); 1341 dst_iovecs[vec].iov_base = (char *)dlrp + 1342 sizeof (lr_t); 1343 dst_iovecs[vec].iov_len = crypt_len; 1344 1345 /* copy the bp now since it will not be encrypted */ 1346 bcopy(slrp + sizeof (lr_write_t) - sizeof (blkptr_t), 1347 dlrp + sizeof (lr_write_t) - sizeof (blkptr_t), 1348 sizeof (blkptr_t)); 1349 bcopy(slrp + sizeof (lr_write_t) - sizeof (blkptr_t), 1350 aadp, sizeof (blkptr_t)); 1351 aadp += sizeof (blkptr_t); 1352 aad_len += sizeof (blkptr_t); 1353 vec++; 1354 total_len += crypt_len; 1355 1356 if (lr_len != sizeof (lr_write_t)) { 1357 crypt_len = lr_len - sizeof (lr_write_t); 1358 dst_iovecs[vec].iov_base = (char *) 1359 dlrp + sizeof (lr_write_t); 1360 dst_iovecs[vec].iov_len = crypt_len; 1361 vec++; 1362 total_len += crypt_len; 1363 } 1364 } else { 1365 crypt_len = lr_len - sizeof (lr_t); 1366 dst_iovecs[vec].iov_base = (char *)dlrp + 1367 sizeof (lr_t); 1368 dst_iovecs[vec].iov_len = crypt_len; 1369 vec++; 1370 total_len += crypt_len; 1371 } 1372 } 1373 1374 /* The last iovec will contain the MAC. */ 1375 ASSERT3U(vec, ==, nr_iovecs - 1); 1376 1377 /* AAD */ 1378 dst_iovecs[0].iov_base = aadbuf; 1379 dst_iovecs[0].iov_len = aad_len; 1380 /* MAC */ 1381 dst_iovecs[vec].iov_base = 0; 1382 dst_iovecs[vec].iov_len = 0; 1383 1384 *no_crypt = (vec == 1); 1385 *enc_len = total_len; 1386 *authbuf = aadbuf; 1387 *auth_len = aad_len; 1388 out_uio->uio_iov = dst_iovecs; 1389 out_uio->uio_iovcnt = nr_iovecs; 1390 1391 return (0); 1392 } 1393 1394 /* 1395 * Special case handling routine for encrypting / decrypting dnode blocks. 1396 */ 1397 static int 1398 zio_crypt_init_uios_dnode(boolean_t encrypt, uint64_t version, 1399 uint8_t *plainbuf, uint8_t *cipherbuf, uint_t datalen, boolean_t byteswap, 1400 uio_t *puio, uio_t *out_uio, uint_t *enc_len, uint8_t **authbuf, 1401 uint_t *auth_len, boolean_t *no_crypt) 1402 { 1403 uint8_t *aadbuf = zio_buf_alloc(datalen); 1404 uint8_t *src, *dst, *aadp; 1405 dnode_phys_t *dnp, *adnp, *sdnp, *ddnp; 1406 iovec_t *dst_iovecs; 1407 uint_t nr_iovecs, crypt_len, vec; 1408 uint_t aad_len = 0, total_len = 0; 1409 uint_t i, j, max_dnp = datalen >> DNODE_SHIFT; 1410 1411 if (encrypt) { 1412 src = plainbuf; 1413 dst = cipherbuf; 1414 } else { 1415 src = cipherbuf; 1416 dst = plainbuf; 1417 } 1418 bcopy(src, dst, datalen); 1419 1420 sdnp = (dnode_phys_t *)src; 1421 ddnp = (dnode_phys_t *)dst; 1422 aadp = aadbuf; 1423 1424 /* 1425 * Count the number of iovecs we will need to do the encryption by 1426 * counting the number of bonus buffers that need to be encrypted. 1427 */ 1428 1429 /* We need at least two iovecs -- one for the AAD, one for the MAC. */ 1430 nr_iovecs = 2; 1431 1432 for (i = 0; i < max_dnp; i += sdnp[i].dn_extra_slots + 1) { 1433 /* 1434 * This block may still be byteswapped. However, all of the 1435 * values we use are either uint8_t's (for which byteswapping 1436 * is a noop) or a * != 0 check, which will work regardless 1437 * of whether or not we byteswap. 1438 */ 1439 if (sdnp[i].dn_type != DMU_OT_NONE && 1440 DMU_OT_IS_ENCRYPTED(sdnp[i].dn_bonustype) && 1441 sdnp[i].dn_bonuslen != 0) { 1442 nr_iovecs++; 1443 } 1444 } 1445 1446 dst_iovecs = kmem_alloc(nr_iovecs * sizeof (iovec_t), KM_SLEEP); 1447 1448 /* 1449 * Iterate through the dnodes again, this time filling in the uios 1450 * we allocated earlier. We also concatenate any data we want to 1451 * authenticate onto aadbuf. 1452 */ 1453 1454 /* The first iovec will contain the authbuf. */ 1455 vec = 1; 1456 1457 for (i = 0; i < max_dnp; i += sdnp[i].dn_extra_slots + 1) { 1458 dnp = &sdnp[i]; 1459 1460 /* copy over the core fields and blkptrs (kept as plaintext) */ 1461 bcopy(dnp, &ddnp[i], (uint8_t *)DN_BONUS(dnp) - (uint8_t *)dnp); 1462 1463 if (dnp->dn_flags & DNODE_FLAG_SPILL_BLKPTR) { 1464 bcopy(DN_SPILL_BLKPTR(dnp), DN_SPILL_BLKPTR(&ddnp[i]), 1465 sizeof (blkptr_t)); 1466 } 1467 1468 /* 1469 * Handle authenticated data. We authenticate everything in 1470 * the dnode that can be brought over when we do a raw send. 1471 * This includes all of the core fields as well as the MACs 1472 * stored in the bp checksums and all of the portable bits 1473 * from blk_prop. We include the dnode padding here in case it 1474 * ever gets used in the future. Some dn_flags and dn_used are 1475 * not portable so we mask those out values out of the 1476 * authenticated data. 1477 */ 1478 crypt_len = offsetof(dnode_phys_t, dn_blkptr); 1479 bcopy(dnp, aadp, crypt_len); 1480 adnp = (dnode_phys_t *)aadp; 1481 adnp->dn_flags &= DNODE_CRYPT_PORTABLE_FLAGS_MASK; 1482 adnp->dn_used = 0; 1483 aadp += crypt_len; 1484 aad_len += crypt_len; 1485 1486 for (j = 0; j < dnp->dn_nblkptr; j++) { 1487 zio_crypt_bp_do_aad_updates(&aadp, &aad_len, 1488 version, byteswap, &dnp->dn_blkptr[j]); 1489 } 1490 1491 if (dnp->dn_flags & DNODE_FLAG_SPILL_BLKPTR) { 1492 zio_crypt_bp_do_aad_updates(&aadp, &aad_len, 1493 version, byteswap, DN_SPILL_BLKPTR(dnp)); 1494 } 1495 1496 /* 1497 * If this bonus buffer needs to be encrypted, we prepare an 1498 * iovec_t. The encryption / decryption functions will fill 1499 * this in for us with the encrypted or decrypted data. 1500 * Otherwise we add the bonus buffer to the authenticated 1501 * data buffer and copy it over to the destination. The 1502 * encrypted iovec extends to DN_MAX_BONUS_LEN(dnp) so that 1503 * we can guarantee alignment with the AES block size 1504 * (128 bits). 1505 */ 1506 crypt_len = DN_MAX_BONUS_LEN(dnp); 1507 if (dnp->dn_type != DMU_OT_NONE && 1508 DMU_OT_IS_ENCRYPTED(dnp->dn_bonustype) && 1509 dnp->dn_bonuslen != 0) { 1510 dst_iovecs[vec].iov_base = DN_BONUS(&ddnp[i]); 1511 dst_iovecs[vec].iov_len = crypt_len; 1512 1513 vec++; 1514 total_len += crypt_len; 1515 } else { 1516 bcopy(DN_BONUS(dnp), DN_BONUS(&ddnp[i]), crypt_len); 1517 bcopy(DN_BONUS(dnp), aadp, crypt_len); 1518 aadp += crypt_len; 1519 aad_len += crypt_len; 1520 } 1521 } 1522 1523 /* The last iovec will contain the MAC. */ 1524 ASSERT3U(vec, ==, nr_iovecs - 1); 1525 1526 /* AAD */ 1527 dst_iovecs[0].iov_base = aadbuf; 1528 dst_iovecs[0].iov_len = aad_len; 1529 /* MAC */ 1530 dst_iovecs[vec].iov_base = 0; 1531 dst_iovecs[vec].iov_len = 0; 1532 1533 *no_crypt = (vec == 1); 1534 *enc_len = total_len; 1535 *authbuf = aadbuf; 1536 *auth_len = aad_len; 1537 out_uio->uio_iov = dst_iovecs; 1538 out_uio->uio_iovcnt = nr_iovecs; 1539 1540 return (0); 1541 } 1542 1543 /* ARGSUSED */ 1544 static int 1545 zio_crypt_init_uios_normal(boolean_t encrypt, uint8_t *plainbuf, 1546 uint8_t *cipherbuf, uint_t datalen, uio_t *puio, uio_t *out_uio, 1547 uint_t *enc_len) 1548 { 1549 int ret; 1550 uint_t nr_plain = 1, nr_cipher = 2; 1551 iovec_t *plain_iovecs = NULL, *cipher_iovecs = NULL; 1552 void *src, *dst; 1553 1554 cipher_iovecs = kmem_alloc(nr_cipher * sizeof (iovec_t), 1555 KM_SLEEP); 1556 if (!cipher_iovecs) { 1557 ret = SET_ERROR(ENOMEM); 1558 goto error; 1559 } 1560 bzero(cipher_iovecs, nr_cipher * sizeof (iovec_t)); 1561 1562 if (encrypt) { 1563 src = plainbuf; 1564 dst = cipherbuf; 1565 } else { 1566 src = cipherbuf; 1567 dst = plainbuf; 1568 } 1569 bcopy(src, dst, datalen); 1570 cipher_iovecs[0].iov_base = dst; 1571 cipher_iovecs[0].iov_len = datalen; 1572 1573 *enc_len = datalen; 1574 out_uio->uio_iov = cipher_iovecs; 1575 out_uio->uio_iovcnt = nr_cipher; 1576 1577 return (0); 1578 1579 error: 1580 if (plain_iovecs != NULL) 1581 kmem_free(plain_iovecs, nr_plain * sizeof (iovec_t)); 1582 if (cipher_iovecs != NULL) 1583 kmem_free(cipher_iovecs, nr_cipher * sizeof (iovec_t)); 1584 1585 *enc_len = 0; 1586 out_uio->uio_iov = NULL; 1587 out_uio->uio_iovcnt = 0; 1588 1589 return (ret); 1590 } 1591 1592 /* 1593 * This function builds up the plaintext (puio) and ciphertext (cuio) uios so 1594 * that they can be used for encryption and decryption by zio_do_crypt_uio(). 1595 * Most blocks will use zio_crypt_init_uios_normal(), with ZIL and dnode blocks 1596 * requiring special handling to parse out pieces that are to be encrypted. The 1597 * authbuf is used by these special cases to store additional authenticated 1598 * data (AAD) for the encryption modes. 1599 */ 1600 static int 1601 zio_crypt_init_uios(boolean_t encrypt, uint64_t version, dmu_object_type_t ot, 1602 uint8_t *plainbuf, uint8_t *cipherbuf, uint_t datalen, boolean_t byteswap, 1603 uint8_t *mac, uio_t *puio, uio_t *cuio, uint_t *enc_len, uint8_t **authbuf, 1604 uint_t *auth_len, boolean_t *no_crypt) 1605 { 1606 int ret; 1607 iovec_t *mac_iov; 1608 1609 ASSERT(DMU_OT_IS_ENCRYPTED(ot) || ot == DMU_OT_NONE); 1610 1611 /* route to handler */ 1612 switch (ot) { 1613 case DMU_OT_INTENT_LOG: 1614 ret = zio_crypt_init_uios_zil(encrypt, plainbuf, cipherbuf, 1615 datalen, byteswap, puio, cuio, enc_len, authbuf, auth_len, 1616 no_crypt); 1617 break; 1618 case DMU_OT_DNODE: 1619 ret = zio_crypt_init_uios_dnode(encrypt, version, plainbuf, 1620 cipherbuf, datalen, byteswap, puio, cuio, enc_len, authbuf, 1621 auth_len, no_crypt); 1622 break; 1623 default: 1624 ret = zio_crypt_init_uios_normal(encrypt, plainbuf, cipherbuf, 1625 datalen, puio, cuio, enc_len); 1626 *authbuf = NULL; 1627 *auth_len = 0; 1628 *no_crypt = B_FALSE; 1629 break; 1630 } 1631 1632 if (ret != 0) 1633 goto error; 1634 1635 /* populate the uios */ 1636 cuio->uio_segflg = UIO_SYSSPACE; 1637 1638 mac_iov = ((iovec_t *)&cuio->uio_iov[cuio->uio_iovcnt - 1]); 1639 mac_iov->iov_base = (void *)mac; 1640 mac_iov->iov_len = ZIO_DATA_MAC_LEN; 1641 1642 return (0); 1643 1644 error: 1645 return (ret); 1646 } 1647 1648 void *failed_decrypt_buf; 1649 int faile_decrypt_size; 1650 1651 /* 1652 * Primary encryption / decryption entrypoint for zio data. 1653 */ 1654 int 1655 zio_do_crypt_data(boolean_t encrypt, zio_crypt_key_t *key, 1656 dmu_object_type_t ot, boolean_t byteswap, uint8_t *salt, uint8_t *iv, 1657 uint8_t *mac, uint_t datalen, uint8_t *plainbuf, uint8_t *cipherbuf, 1658 boolean_t *no_crypt) 1659 { 1660 int ret; 1661 boolean_t locked = B_FALSE; 1662 uint64_t crypt = key->zk_crypt; 1663 uint_t keydata_len = zio_crypt_table[crypt].ci_keylen; 1664 uint_t enc_len, auth_len; 1665 uio_t puio, cuio; 1666 uint8_t enc_keydata[MASTER_KEY_MAX_LEN]; 1667 crypto_key_t tmp_ckey, *ckey = NULL; 1668 freebsd_crypt_session_t *tmpl = NULL; 1669 uint8_t *authbuf = NULL; 1670 1671 bzero(&puio, sizeof (uio_t)); 1672 bzero(&cuio, sizeof (uio_t)); 1673 1674 #ifdef FCRYPTO_DEBUG 1675 printf("%s(%s, %p, %p, %d, %p, %p, %u, %s, %p, %p, %p)\n", 1676 __FUNCTION__, 1677 encrypt ? "encrypt" : "decrypt", 1678 key, salt, ot, iv, mac, datalen, 1679 byteswap ? "byteswap" : "native_endian", plainbuf, 1680 cipherbuf, no_crypt); 1681 1682 printf("\tkey = {"); 1683 for (int i = 0; i < key->zk_current_key.ck_length/8; i++) 1684 printf("%02x ", ((uint8_t *)key->zk_current_key.ck_data)[i]); 1685 printf("}\n"); 1686 #endif 1687 /* create uios for encryption */ 1688 ret = zio_crypt_init_uios(encrypt, key->zk_version, ot, plainbuf, 1689 cipherbuf, datalen, byteswap, mac, &puio, &cuio, &enc_len, 1690 &authbuf, &auth_len, no_crypt); 1691 if (ret != 0) 1692 return (ret); 1693 1694 /* 1695 * If the needed key is the current one, just use it. Otherwise we 1696 * need to generate a temporary one from the given salt + master key. 1697 * If we are encrypting, we must return a copy of the current salt 1698 * so that it can be stored in the blkptr_t. 1699 */ 1700 rw_enter(&key->zk_salt_lock, RW_READER); 1701 locked = B_TRUE; 1702 1703 if (bcmp(salt, key->zk_salt, ZIO_DATA_SALT_LEN) == 0) { 1704 ckey = &key->zk_current_key; 1705 tmpl = &key->zk_session; 1706 } else { 1707 rw_exit(&key->zk_salt_lock); 1708 locked = B_FALSE; 1709 1710 ret = hkdf_sha512(key->zk_master_keydata, keydata_len, NULL, 0, 1711 salt, ZIO_DATA_SALT_LEN, enc_keydata, keydata_len); 1712 if (ret != 0) 1713 goto error; 1714 tmp_ckey.ck_format = CRYPTO_KEY_RAW; 1715 tmp_ckey.ck_data = enc_keydata; 1716 tmp_ckey.ck_length = CRYPTO_BYTES2BITS(keydata_len); 1717 1718 ckey = &tmp_ckey; 1719 tmpl = NULL; 1720 } 1721 1722 /* perform the encryption / decryption */ 1723 ret = zio_do_crypt_uio_opencrypto(encrypt, tmpl, key->zk_crypt, 1724 ckey, iv, enc_len, &cuio, auth_len); 1725 if (ret != 0) 1726 goto error; 1727 if (locked) { 1728 rw_exit(&key->zk_salt_lock); 1729 locked = B_FALSE; 1730 } 1731 1732 if (authbuf != NULL) 1733 zio_buf_free(authbuf, datalen); 1734 if (ckey == &tmp_ckey) 1735 bzero(enc_keydata, keydata_len); 1736 zio_crypt_destroy_uio(&puio); 1737 zio_crypt_destroy_uio(&cuio); 1738 1739 return (0); 1740 1741 error: 1742 if (!encrypt) { 1743 if (failed_decrypt_buf != NULL) 1744 kmem_free(failed_decrypt_buf, failed_decrypt_size); 1745 failed_decrypt_buf = kmem_alloc(datalen, KM_SLEEP); 1746 failed_decrypt_size = datalen; 1747 bcopy(cipherbuf, failed_decrypt_buf, datalen); 1748 } 1749 if (locked) 1750 rw_exit(&key->zk_salt_lock); 1751 if (authbuf != NULL) 1752 zio_buf_free(authbuf, datalen); 1753 if (ckey == &tmp_ckey) 1754 bzero(enc_keydata, keydata_len); 1755 zio_crypt_destroy_uio(&puio); 1756 zio_crypt_destroy_uio(&cuio); 1757 return (SET_ERROR(ret)); 1758 } 1759 1760 /* 1761 * Simple wrapper around zio_do_crypt_data() to work with abd's instead of 1762 * linear buffers. 1763 */ 1764 int 1765 zio_do_crypt_abd(boolean_t encrypt, zio_crypt_key_t *key, dmu_object_type_t ot, 1766 boolean_t byteswap, uint8_t *salt, uint8_t *iv, uint8_t *mac, 1767 uint_t datalen, abd_t *pabd, abd_t *cabd, boolean_t *no_crypt) 1768 { 1769 int ret; 1770 void *ptmp, *ctmp; 1771 1772 if (encrypt) { 1773 ptmp = abd_borrow_buf_copy(pabd, datalen); 1774 ctmp = abd_borrow_buf(cabd, datalen); 1775 } else { 1776 ptmp = abd_borrow_buf(pabd, datalen); 1777 ctmp = abd_borrow_buf_copy(cabd, datalen); 1778 } 1779 1780 ret = zio_do_crypt_data(encrypt, key, ot, byteswap, salt, iv, mac, 1781 datalen, ptmp, ctmp, no_crypt); 1782 if (ret != 0) 1783 goto error; 1784 1785 if (encrypt) { 1786 abd_return_buf(pabd, ptmp, datalen); 1787 abd_return_buf_copy(cabd, ctmp, datalen); 1788 } else { 1789 abd_return_buf_copy(pabd, ptmp, datalen); 1790 abd_return_buf(cabd, ctmp, datalen); 1791 } 1792 1793 return (0); 1794 1795 error: 1796 if (encrypt) { 1797 abd_return_buf(pabd, ptmp, datalen); 1798 abd_return_buf_copy(cabd, ctmp, datalen); 1799 } else { 1800 abd_return_buf_copy(pabd, ptmp, datalen); 1801 abd_return_buf(cabd, ctmp, datalen); 1802 } 1803 1804 return (SET_ERROR(ret)); 1805 } 1806 1807 #if defined(_KERNEL) && defined(HAVE_SPL) 1808 /* BEGIN CSTYLED */ 1809 module_param(zfs_key_max_salt_uses, ulong, 0644); 1810 MODULE_PARM_DESC(zfs_key_max_salt_uses, "Max number of times a salt value " 1811 "can be used for generating encryption keys before it is rotated"); 1812 /* END CSTYLED */ 1813 #endif 1814