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Diffstat (limited to 'module/zfs/zio_crypt.c')
| -rw-r--r-- | module/zfs/zio_crypt.c | 2037 |
1 files changed, 2037 insertions, 0 deletions
diff --git a/module/zfs/zio_crypt.c b/module/zfs/zio_crypt.c new file mode 100644 index 000000000..8fcf51550 --- /dev/null +++ b/module/zfs/zio_crypt.c @@ -0,0 +1,2037 @@ +/* + * CDDL HEADER START + * + * This file and its contents are supplied under the terms of the + * Common Development and Distribution License ("CDDL"), version 1.0. + * You may only use this file in accordance with the terms of version + * 1.0 of the CDDL. + * + * A full copy of the text of the CDDL should have accompanied this + * source. A copy of the CDDL is also available via the Internet at + * http://www.illumos.org/license/CDDL. + * + * CDDL HEADER END + */ + +/* + * Copyright (c) 2017, Datto, Inc. All rights reserved. + */ + +#include <sys/zio_crypt.h> +#include <sys/dmu.h> +#include <sys/dmu_objset.h> +#include <sys/dnode.h> +#include <sys/fs/zfs.h> +#include <sys/zio.h> +#include <sys/zil.h> +#include <sys/sha2.h> + +/* + * This file is responsible for handling all of the details of generating + * encryption parameters and performing encryption and authentication. + * + * BLOCK ENCRYPTION PARAMETERS: + * Encryption /Authentication Algorithm Suite (crypt): + * The encryption algorithm, mode, and key length we are going to use. We + * currently support AES in either GCM or CCM modes with 128, 192, and 256 bit + * keys. All authentication is currently done with SHA512-HMAC. + * + * Plaintext: + * The unencrypted data that we want to encrypt. + * + * Initialization Vector (IV): + * An initialization vector for the encryption algorithms. This is used to + * "tweak" the encryption algorithms so that two blocks of the same data are + * encrypted into different ciphertext outputs, thus obfuscating block patterns. + * The supported encryption modes (AES-GCM and AES-CCM) require that an IV is + * never reused with the same encryption key. This value is stored unencrypted + * and must simply be provided to the decryption function. We use a 96 bit IV + * (as recommended by NIST) for all block encryption. For non-dedup blocks we + * derive the IV randomly. The first 64 bits of the IV are stored in the second + * word of DVA[2] and the remaining 32 bits are stored in the upper 32 bits of + * blk_fill. This is safe because encrypted blocks can't use the upper 32 bits + * of blk_fill. We only encrypt level 0 blocks, which normally have a fill count + * of 1. The only exception is for DMU_OT_DNODE objects, where the fill count of + * level 0 blocks is the number of allocated dnodes in that block. The on-disk + * format supports at most 2^15 slots per L0 dnode block, because the maximum + * block size is 16MB (2^24). In either case, for level 0 blocks this number + * will still be smaller than UINT32_MAX so it is safe to store the IV in the + * top 32 bits of blk_fill, while leaving the bottom 32 bits of the fill count + * for the dnode code. + * + * Master key: + * This is the most important secret data of an encrypted dataset. It is used + * along with the salt to generate that actual encryption keys via HKDF. We + * do not use the master key to directly encrypt any data because there are + * theoretical limits on how much data can actually be safely encrypted with + * any encryption mode. The master key is stored encrypted on disk with the + * user's wrapping key. Its length is determined by the encryption algorithm. + * For details on how this is stored see the block comment in dsl_crypt.c + * + * Salt: + * Used as an input to the HKDF function, along with the master key. We use a + * 64 bit salt, stored unencrypted in the first word of DVA[2]. Any given salt + * can be used for encrypting many blocks, so we cache the current salt and the + * associated derived key in zio_crypt_t so we do not need to derive it again + * needlessly. + * + * Encryption Key: + * A secret binary key, generated from an HKDF function used to encrypt and + * decrypt data. + * + * Message Authenication Code (MAC) + * The MAC is an output of authenticated encryption modes such as AES-GCM and + * AES-CCM. Its purpose is to ensure that an attacker cannot modify encrypted + * data on disk and return garbage to the application. Effectively, it is a + * checksum that can not be reproduced by an attacker. We store the MAC in the + * second 128 bits of blk_cksum, leaving the first 128 bits for a truncated + * regular checksum of the ciphertext which can be used for scrubbing. + * + * OBJECT AUTHENTICATION: + * Some object types, such as DMU_OT_MASTER_NODE cannot be encrypted because + * they contain some info that always needs to be readable. To prevent this + * data from being altered, we authenticate this data using SHA512-HMAC. This + * will produce a MAC (similar to the one produced via encryption) which can + * be used to verify the object was not modified. HMACs do not require key + * rotation or IVs, so we can keep up to the full 3 copies of authenticated + * data. + * + * ZIL ENCRYPTION: + * ZIL blocks have their bp written to disk ahead of the associated data, so we + * cannot store the MAC there as we normally do. For these blocks the MAC is + * stored in the embedded checksum within the zil_chain_t header. The salt and + * IV are generated for the block on bp allocation instead of at encryption + * time. In addition, ZIL blocks have some pieces that must be left in plaintext + * for claiming even though all of the sensitive user data still needs to be + * encrypted. The function zio_crypt_init_uios_zil() handles parsing which + * pieces of the block need to be encrypted. All data that is not encrypted is + * authenticated using the AAD mechanisms that the supported encryption modes + * provide for. In order to preserve the semantics of the ZIL for encrypted + * datasets, the ZIL is not protected at the objset level as described below. + * + * DNODE ENCRYPTION: + * Similarly to ZIL blocks, the core part of each dnode_phys_t needs to be left + * in plaintext for scrubbing and claiming, but the bonus buffers might contain + * sensitive user data. The function zio_crypt_init_uios_dnode() handles parsing + * which which pieces of the block need to be encrypted. For more details about + * dnode authentication and encryption, see zio_crypt_init_uios_dnode(). + * + * OBJECT SET AUTHENTICATION: + * Up to this point, everything we have encrypted and authenticated has been + * at level 0 (or -2 for the ZIL). If we did not do any further work the + * on-disk format would be susceptible to attacks that deleted or rearrannged + * the order of level 0 blocks. Ideally, the cleanest solution would be to + * maintain a tree of authentication MACs going up the bp tree. However, this + * presents a problem for raw sends. Send files do not send information about + * indirect blocks so there would be no convenient way to transfer the MACs and + * they cannot be recalculated on the receive side without the master key which + * would defeat one of the purposes of raw sends in the first place. Instead, + * for the indirect levels of the bp tree, we use a regular SHA512 of the MACs + * from the level below. We also include some portable fields from blk_prop such + * as the lsize and compression algorithm to prevent the data from being + * misinterpretted. + * + * At the objset level, we maintain 2 seperate 256 bit MACs in the + * objset_phys_t. The first one is "portable" and is the logical root of the + * MAC tree maintianed in the metadnode's bps. The second, is "local" and is + * used as the root MAC for the user accounting objects, which are also not + * transferred via "zfs send". The portable MAC is sent in the DRR_BEGIN payload + * of the send file. The useraccounting code ensures that the useraccounting + * info is not present upon a receive, so the local MAC can simply be cleared + * out at that time. For more info about objset_phys_t authentication, see + * zio_crypt_do_objset_hmacs(). + * + * CONSIDERATIONS FOR DEDUP: + * In order for dedup to work, blocks that we want to dedup with one another + * need to use the same IV and encryption key, so that they will have the same + * ciphertext. Normally, one should never reuse an IV with the same encryption + * key or else AES-GCM and AES-CCM can both actually leak the plaintext of both + * blocks. In this case, however, since we are using the same plaindata as + * well all that we end up with is a duplicate of the original ciphertext we + * already had. As a result, an attacker with read access to the raw disk will + * be able to tell which blocks are the same but this information is given away + * by dedup anyway. In order to get the same IVs and encryption keys for + * equivalent blocks of data we use an HMAC of the plaindata. We use an HMAC + * here so that a reproducible checksum of the plaindata is never available to + * the attacker. The HMAC key is kept alongside the master key, encrypted on + * disk. The first 64 bits of the HMAC are used in place of the random salt, and + * the next 96 bits are used as the IV. As a result of this mechanism, dedup + * will only work within a clone family since encrypted dedup requires use of + * the same master and HMAC keys. + */ + +/* + * After encrypting many blocks with the same key we may start to run up + * against the theoretical limits of how much data can securely be encrypted + * with a single key using the supported encryption modes. The most obvious + * limitation is that our risk of generating 2 equivalent 96 bit IVs increases + * the more IVs we generate (which both GCM and CCM modes strictly forbid). + * This risk actually grows surprisingly quickly over time according to the + * Birthday Problem. With a total IV space of 2^(96 bits), and assuming we have + * generated n IVs with a cryptographically secure RNG, the approximate + * probability p(n) of a collision is given as: + * + * p(n) ~= e^(-n*(n-1)/(2*(2^96))) + * + * [http://www.math.cornell.edu/~mec/2008-2009/TianyiZheng/Birthday.html] + * + * Assuming that we want to ensure that p(n) never goes over 1 / 1 trillion + * we must not write more than 398,065,730 blocks with the same encryption key. + * Therefore, we rotate our keys after 400,000,000 blocks have been written by + * generating a new random 64 bit salt for our HKDF encryption key generation + * function. + */ +#define ZFS_KEY_MAX_SALT_USES_DEFAULT 400000000 +#define ZFS_CURRENT_MAX_SALT_USES \ + (MIN(zfs_key_max_salt_uses, ZFS_KEY_MAX_SALT_USES_DEFAULT)) +unsigned long zfs_key_max_salt_uses = ZFS_KEY_MAX_SALT_USES_DEFAULT; + +zio_crypt_info_t zio_crypt_table[ZIO_CRYPT_FUNCTIONS] = { + {"", ZC_TYPE_NONE, 0, "inherit"}, + {"", ZC_TYPE_NONE, 0, "on"}, + {"", ZC_TYPE_NONE, 0, "off"}, + {SUN_CKM_AES_CCM, ZC_TYPE_CCM, 16, "aes-128-ccm"}, + {SUN_CKM_AES_CCM, ZC_TYPE_CCM, 24, "aes-192-ccm"}, + {SUN_CKM_AES_CCM, ZC_TYPE_CCM, 32, "aes-256-ccm"}, + {SUN_CKM_AES_GCM, ZC_TYPE_GCM, 16, "aes-128-gcm"}, + {SUN_CKM_AES_GCM, ZC_TYPE_GCM, 24, "aes-192-gcm"}, + {SUN_CKM_AES_GCM, ZC_TYPE_GCM, 32, "aes-256-gcm"} +}; + +static int +hkdf_sha512_extract(uint8_t *salt, uint_t salt_len, uint8_t *key_material, + uint_t km_len, uint8_t *out_buf) +{ + int ret; + crypto_mechanism_t mech; + crypto_key_t key; + crypto_data_t input_cd, output_cd; + + /* initialize HMAC mechanism */ + mech.cm_type = crypto_mech2id(SUN_CKM_SHA512_HMAC); + mech.cm_param = NULL; + mech.cm_param_len = 0; + + /* initialize the salt as a crypto key */ + key.ck_format = CRYPTO_KEY_RAW; + key.ck_length = BYTES_TO_BITS(salt_len); + key.ck_data = salt; + + /* initialize crypto data for the input and output data */ + input_cd.cd_format = CRYPTO_DATA_RAW; + input_cd.cd_offset = 0; + input_cd.cd_length = km_len; + input_cd.cd_raw.iov_base = (char *)key_material; + input_cd.cd_raw.iov_len = input_cd.cd_length; + + output_cd.cd_format = CRYPTO_DATA_RAW; + output_cd.cd_offset = 0; + output_cd.cd_length = SHA512_DIGEST_LEN; + output_cd.cd_raw.iov_base = (char *)out_buf; + output_cd.cd_raw.iov_len = output_cd.cd_length; + + ret = crypto_mac(&mech, &input_cd, &key, NULL, &output_cd, NULL); + if (ret != CRYPTO_SUCCESS) { + ret = SET_ERROR(EIO); + goto error; + } + + return (0); + +error: + return (ret); +} + +static int +hkdf_sha512_expand(uint8_t *extract_key, uint8_t *info, uint_t info_len, + uint8_t *out_buf, uint_t out_len) +{ + int ret; + crypto_mechanism_t mech; + crypto_context_t ctx; + crypto_key_t key; + crypto_data_t T_cd, info_cd, c_cd; + uint_t i, T_len = 0, pos = 0; + uint8_t c; + uint_t N = (out_len + SHA512_DIGEST_LEN) / SHA512_DIGEST_LEN; + uint8_t T[SHA512_DIGEST_LEN]; + + if (N > 255) + return (SET_ERROR(EINVAL)); + + /* initialize HMAC mechanism */ + mech.cm_type = crypto_mech2id(SUN_CKM_SHA512_HMAC); + mech.cm_param = NULL; + mech.cm_param_len = 0; + + /* initialize the salt as a crypto key */ + key.ck_format = CRYPTO_KEY_RAW; + key.ck_length = BYTES_TO_BITS(SHA512_DIGEST_LEN); + key.ck_data = extract_key; + + /* initialize crypto data for the input and output data */ + T_cd.cd_format = CRYPTO_DATA_RAW; + T_cd.cd_offset = 0; + T_cd.cd_raw.iov_base = (char *)T; + + c_cd.cd_format = CRYPTO_DATA_RAW; + c_cd.cd_offset = 0; + c_cd.cd_length = 1; + c_cd.cd_raw.iov_base = (char *)&c; + c_cd.cd_raw.iov_len = c_cd.cd_length; + + info_cd.cd_format = CRYPTO_DATA_RAW; + info_cd.cd_offset = 0; + info_cd.cd_length = info_len; + info_cd.cd_raw.iov_base = (char *)info; + info_cd.cd_raw.iov_len = info_cd.cd_length; + + for (i = 1; i <= N; i++) { + c = i; + + T_cd.cd_length = T_len; + T_cd.cd_raw.iov_len = T_cd.cd_length; + + ret = crypto_mac_init(&mech, &key, NULL, &ctx, NULL); + if (ret != CRYPTO_SUCCESS) { + ret = SET_ERROR(EIO); + goto error; + } + + ret = crypto_mac_update(ctx, &T_cd, NULL); + if (ret != CRYPTO_SUCCESS) { + ret = SET_ERROR(EIO); + goto error; + } + + ret = crypto_mac_update(ctx, &info_cd, NULL); + if (ret != CRYPTO_SUCCESS) { + ret = SET_ERROR(EIO); + goto error; + } + + ret = crypto_mac_update(ctx, &c_cd, NULL); + if (ret != CRYPTO_SUCCESS) { + ret = SET_ERROR(EIO); + goto error; + } + + T_len = SHA512_DIGEST_LEN; + T_cd.cd_length = T_len; + T_cd.cd_raw.iov_len = T_cd.cd_length; + + ret = crypto_mac_final(ctx, &T_cd, NULL); + if (ret != CRYPTO_SUCCESS) { + ret = SET_ERROR(EIO); + goto error; + } + + bcopy(T, out_buf + pos, + (i != N) ? SHA512_DIGEST_LEN : (out_len - pos)); + pos += SHA512_DIGEST_LEN; + } + + return (0); + +error: + return (ret); +} + +/* + * HKDF is designed to be a relatively fast function for deriving keys from a + * master key + a salt. We use this function to generate new encryption keys + * so as to avoid hitting the cryptographic limits of the underlying + * encryption modes. Note that, for the sake of deriving encryption keys, the + * info parameter is called the "salt" everywhere else in the code. + */ +static int +hkdf_sha512(uint8_t *key_material, uint_t km_len, uint8_t *salt, + uint_t salt_len, uint8_t *info, uint_t info_len, uint8_t *output_key, + uint_t out_len) +{ + int ret; + uint8_t extract_key[SHA512_DIGEST_LEN]; + + ret = hkdf_sha512_extract(salt, salt_len, key_material, km_len, + extract_key); + if (ret != 0) + goto error; + + ret = hkdf_sha512_expand(extract_key, info, info_len, output_key, + out_len); + if (ret != 0) + goto error; + + return (0); + +error: + return (ret); +} + +void +zio_crypt_key_destroy(zio_crypt_key_t *key) +{ + rw_destroy(&key->zk_salt_lock); + + /* free crypto templates */ + crypto_destroy_ctx_template(key->zk_current_tmpl); + crypto_destroy_ctx_template(key->zk_hmac_tmpl); + + /* zero out sensitive data */ + bzero(key, sizeof (zio_crypt_key_t)); +} + +int +zio_crypt_key_init(uint64_t crypt, zio_crypt_key_t *key) +{ + int ret; + crypto_mechanism_t mech; + uint_t keydata_len; + + ASSERT(key != NULL); + ASSERT3U(crypt, <, ZIO_CRYPT_FUNCTIONS); + + keydata_len = zio_crypt_table[crypt].ci_keylen; + bzero(key, sizeof (zio_crypt_key_t)); + + /* fill keydata buffers and salt with random data */ + ret = random_get_bytes((uint8_t *)&key->zk_guid, sizeof (uint64_t)); + if (ret != 0) + goto error; + + ret = random_get_bytes(key->zk_master_keydata, keydata_len); + if (ret != 0) + goto error; + + ret = random_get_bytes(key->zk_hmac_keydata, SHA512_HMAC_KEYLEN); + if (ret != 0) + goto error; + + ret = random_get_bytes(key->zk_salt, ZIO_DATA_SALT_LEN); + if (ret != 0) + goto error; + + /* derive the current key from the master key */ + ret = hkdf_sha512(key->zk_master_keydata, keydata_len, NULL, 0, + key->zk_salt, ZIO_DATA_SALT_LEN, key->zk_current_keydata, + keydata_len); + if (ret != 0) + goto error; + + /* initialize keys for the ICP */ + key->zk_current_key.ck_format = CRYPTO_KEY_RAW; + key->zk_current_key.ck_data = key->zk_current_keydata; + key->zk_current_key.ck_length = BYTES_TO_BITS(keydata_len); + + key->zk_hmac_key.ck_format = CRYPTO_KEY_RAW; + key->zk_hmac_key.ck_data = &key->zk_hmac_key; + key->zk_hmac_key.ck_length = BYTES_TO_BITS(SHA512_HMAC_KEYLEN); + + /* + * Initialize the crypto templates. It's ok if this fails because + * this is just an optimization. + */ + mech.cm_type = crypto_mech2id(zio_crypt_table[crypt].ci_mechname); + ret = crypto_create_ctx_template(&mech, &key->zk_current_key, + &key->zk_current_tmpl, KM_SLEEP); + if (ret != CRYPTO_SUCCESS) + key->zk_current_tmpl = NULL; + + mech.cm_type = crypto_mech2id(SUN_CKM_SHA512_HMAC); + ret = crypto_create_ctx_template(&mech, &key->zk_hmac_key, + &key->zk_hmac_tmpl, KM_SLEEP); + if (ret != CRYPTO_SUCCESS) + key->zk_hmac_tmpl = NULL; + + key->zk_crypt = crypt; + key->zk_salt_count = 0; + rw_init(&key->zk_salt_lock, NULL, RW_DEFAULT, NULL); + + return (0); + +error: + zio_crypt_key_destroy(key); + return (ret); +} + +static int +zio_crypt_key_change_salt(zio_crypt_key_t *key) +{ + int ret = 0; + uint8_t salt[ZIO_DATA_SALT_LEN]; + crypto_mechanism_t mech; + uint_t keydata_len = zio_crypt_table[key->zk_crypt].ci_keylen; + + /* generate a new salt */ + ret = random_get_bytes(salt, ZIO_DATA_SALT_LEN); + if (ret != 0) + goto error; + + rw_enter(&key->zk_salt_lock, RW_WRITER); + + /* someone beat us to the salt rotation, just unlock and return */ + if (key->zk_salt_count < ZFS_CURRENT_MAX_SALT_USES) + goto out_unlock; + + /* derive the current key from the master key and the new salt */ + ret = hkdf_sha512(key->zk_master_keydata, keydata_len, NULL, 0, + salt, ZIO_DATA_SALT_LEN, key->zk_current_keydata, keydata_len); + if (ret != 0) + goto out_unlock; + + /* assign the salt and reset the usage count */ + bcopy(salt, key->zk_salt, ZIO_DATA_SALT_LEN); + key->zk_salt_count = 0; + + /* destroy the old context template and create the new one */ + crypto_destroy_ctx_template(key->zk_current_tmpl); + ret = crypto_create_ctx_template(&mech, &key->zk_current_key, + &key->zk_current_tmpl, KM_SLEEP); + if (ret != CRYPTO_SUCCESS) + key->zk_current_tmpl = NULL; + + rw_exit(&key->zk_salt_lock); + + return (0); + +out_unlock: + rw_exit(&key->zk_salt_lock); +error: + return (ret); +} + +/* See comment above zfs_key_max_salt_uses definition for details */ +int +zio_crypt_key_get_salt(zio_crypt_key_t *key, uint8_t *salt) +{ + int ret; + boolean_t salt_change; + + rw_enter(&key->zk_salt_lock, RW_READER); + + bcopy(key->zk_salt, salt, ZIO_DATA_SALT_LEN); + salt_change = (atomic_inc_64_nv(&key->zk_salt_count) >= + ZFS_CURRENT_MAX_SALT_USES); + + rw_exit(&key->zk_salt_lock); + + if (salt_change) { + ret = zio_crypt_key_change_salt(key); + if (ret != 0) + goto error; + } + + return (0); + +error: + return (ret); +} + +/* + * This function handles all encryption and decryption in zfs. When + * encrypting it expects puio to reference the plaintext and cuio to + * reference the cphertext. cuio must have enough space for the + * ciphertext + room for a MAC. datalen should be the length of the + * plaintext / ciphertext alone. + */ +static int +zio_do_crypt_uio(boolean_t encrypt, uint64_t crypt, crypto_key_t *key, + crypto_ctx_template_t tmpl, uint8_t *ivbuf, uint_t datalen, + uio_t *puio, uio_t *cuio, uint8_t *authbuf, uint_t auth_len) +{ + int ret; + crypto_data_t plaindata, cipherdata; + CK_AES_CCM_PARAMS ccmp; + CK_AES_GCM_PARAMS gcmp; + crypto_mechanism_t mech; + zio_crypt_info_t crypt_info; + uint_t plain_full_len, maclen; + + ASSERT3U(crypt, <, ZIO_CRYPT_FUNCTIONS); + ASSERT3U(key->ck_format, ==, CRYPTO_KEY_RAW); + + /* lookup the encryption info */ + crypt_info = zio_crypt_table[crypt]; + + /* the mac will always be the last iovec_t in the cipher uio */ + maclen = cuio->uio_iov[cuio->uio_iovcnt - 1].iov_len; + + ASSERT(maclen <= ZIO_DATA_MAC_LEN); + + /* setup encryption mechanism (same as crypt) */ + mech.cm_type = crypto_mech2id(crypt_info.ci_mechname); + + /* + * Strangely, the ICP requires that plain_full_len must include + * the MAC length when decrypting, even though the UIO does not + * need to have the extra space allocated. + */ + if (encrypt) { + plain_full_len = datalen; + } else { + plain_full_len = datalen + maclen; + } + + /* + * setup encryption params (currently only AES CCM and AES GCM + * are supported) + */ + if (crypt_info.ci_crypt_type == ZC_TYPE_CCM) { + ccmp.ulNonceSize = ZIO_DATA_IV_LEN; + ccmp.ulAuthDataSize = auth_len; + ccmp.authData = authbuf; + ccmp.ulMACSize = maclen; + ccmp.nonce = ivbuf; + ccmp.ulDataSize = plain_full_len; + + mech.cm_param = (char *)(&ccmp); + mech.cm_param_len = sizeof (CK_AES_CCM_PARAMS); + } else { + gcmp.ulIvLen = ZIO_DATA_IV_LEN; + gcmp.ulIvBits = BYTES_TO_BITS(ZIO_DATA_IV_LEN); + gcmp.ulAADLen = auth_len; + gcmp.pAAD = authbuf; + gcmp.ulTagBits = BYTES_TO_BITS(maclen); + gcmp.pIv = ivbuf; + + mech.cm_param = (char *)(&gcmp); + mech.cm_param_len = sizeof (CK_AES_GCM_PARAMS); + } + + /* populate the cipher and plain data structs. */ + plaindata.cd_format = CRYPTO_DATA_UIO; + plaindata.cd_offset = 0; + plaindata.cd_uio = puio; + plaindata.cd_miscdata = NULL; + plaindata.cd_length = plain_full_len; + + cipherdata.cd_format = CRYPTO_DATA_UIO; + cipherdata.cd_offset = 0; + cipherdata.cd_uio = cuio; + cipherdata.cd_miscdata = NULL; + cipherdata.cd_length = datalen + maclen; + + /* perform the actual encryption */ + if (encrypt) { + ret = crypto_encrypt(&mech, &plaindata, key, tmpl, &cipherdata, + NULL); + if (ret != CRYPTO_SUCCESS) { + ret = SET_ERROR(EIO); + goto error; + } + } else { + ret = crypto_decrypt(&mech, &cipherdata, key, tmpl, &plaindata, + NULL); + if (ret != CRYPTO_SUCCESS) { + ASSERT3U(ret, ==, CRYPTO_INVALID_MAC); + ret = SET_ERROR(ECKSUM); + goto error; + } + } + + return (0); + +error: + return (ret); +} + +int +zio_crypt_key_wrap(crypto_key_t *cwkey, zio_crypt_key_t *key, uint8_t *iv, + uint8_t *mac, uint8_t *keydata_out, uint8_t *hmac_keydata_out) +{ + int ret; + uio_t puio, cuio; + iovec_t plain_iovecs[2], cipher_iovecs[3]; + uint64_t crypt = key->zk_crypt; + uint64_t le_guid = LE_64(key->zk_guid); + uint_t enc_len, keydata_len; + + ASSERT3U(crypt, <, ZIO_CRYPT_FUNCTIONS); + ASSERT3U(cwkey->ck_format, ==, CRYPTO_KEY_RAW); + + keydata_len = zio_crypt_table[crypt].ci_keylen; + + /* generate iv for wrapping the master and hmac key */ + ret = random_get_pseudo_bytes(iv, WRAPPING_IV_LEN); + if (ret != 0) + goto error; + + /* initialize uio_ts */ + plain_iovecs[0].iov_base = key->zk_master_keydata; + plain_iovecs[0].iov_len = keydata_len; + plain_iovecs[1].iov_base = key->zk_hmac_keydata; + plain_iovecs[1].iov_len = SHA512_HMAC_KEYLEN; + + cipher_iovecs[0].iov_base = keydata_out; + cipher_iovecs[0].iov_len = keydata_len; + cipher_iovecs[1].iov_base = hmac_keydata_out; + cipher_iovecs[1].iov_len = SHA512_HMAC_KEYLEN; + cipher_iovecs[2].iov_base = mac; + cipher_iovecs[2].iov_len = WRAPPING_MAC_LEN; + + enc_len = zio_crypt_table[crypt].ci_keylen + SHA512_HMAC_KEYLEN; + puio.uio_iov = plain_iovecs; + puio.uio_iovcnt = 2; + puio.uio_segflg = UIO_SYSSPACE; + cuio.uio_iov = cipher_iovecs; + cuio.uio_iovcnt = 3; + cuio.uio_segflg = UIO_SYSSPACE; + + /* encrypt the keys and store the resulting ciphertext and mac */ + ret = zio_do_crypt_uio(B_TRUE, crypt, cwkey, NULL, iv, enc_len, + &puio, &cuio, (uint8_t *)&le_guid, sizeof (uint64_t)); + if (ret != 0) + goto error; + + return (0); + +error: + return (ret); +} + +int +zio_crypt_key_unwrap(crypto_key_t *cwkey, uint64_t crypt, uint64_t guid, + uint8_t *keydata, uint8_t *hmac_keydata, uint8_t *iv, uint8_t *mac, + zio_crypt_key_t *key) +{ + int ret; + crypto_mechanism_t mech; + uio_t puio, cuio; + iovec_t plain_iovecs[2], cipher_iovecs[3]; + uint_t enc_len, keydata_len; + uint64_t le_guid = LE_64(guid); + + ASSERT3U(crypt, <, ZIO_CRYPT_FUNCTIONS); + ASSERT3U(cwkey->ck_format, ==, CRYPTO_KEY_RAW); + + keydata_len = zio_crypt_table[crypt].ci_keylen; + + /* initialize uio_ts */ + plain_iovecs[0].iov_base = key->zk_master_keydata; + plain_iovecs[0].iov_len = keydata_len; + plain_iovecs[1].iov_base = key->zk_hmac_keydata; + plain_iovecs[1].iov_len = SHA512_HMAC_KEYLEN; + + cipher_iovecs[0].iov_base = keydata; + cipher_iovecs[0].iov_len = keydata_len; + cipher_iovecs[1].iov_base = hmac_keydata; + cipher_iovecs[1].iov_len = SHA512_HMAC_KEYLEN; + cipher_iovecs[2].iov_base = mac; + cipher_iovecs[2].iov_len = WRAPPING_MAC_LEN; + + enc_len = keydata_len + SHA512_HMAC_KEYLEN; + puio.uio_iov = plain_iovecs; + puio.uio_segflg = UIO_SYSSPACE; + puio.uio_iovcnt = 2; + cuio.uio_iov = cipher_iovecs; + cuio.uio_iovcnt = 3; + cuio.uio_segflg = UIO_SYSSPACE; + + /* decrypt the keys and store the result in the output buffers */ + ret = zio_do_crypt_uio(B_FALSE, crypt, cwkey, NULL, iv, enc_len, + &puio, &cuio, (uint8_t *)&le_guid, sizeof (uint64_t)); + if (ret != 0) + goto error; + + /* generate a fresh salt */ + ret = random_get_bytes(key->zk_salt, ZIO_DATA_SALT_LEN); + if (ret != 0) + goto error; + + /* derive the current key from the master key */ + ret = hkdf_sha512(key->zk_master_keydata, keydata_len, NULL, 0, + key->zk_salt, ZIO_DATA_SALT_LEN, key->zk_current_keydata, + keydata_len); + if (ret != 0) + goto error; + + /* initialize keys for ICP */ + key->zk_current_key.ck_format = CRYPTO_KEY_RAW; + key->zk_current_key.ck_data = key->zk_current_keydata; + key->zk_current_key.ck_length = BYTES_TO_BITS(keydata_len); + + key->zk_hmac_key.ck_format = CRYPTO_KEY_RAW; + key->zk_hmac_key.ck_data = key->zk_hmac_keydata; + key->zk_hmac_key.ck_length = BYTES_TO_BITS(SHA512_HMAC_KEYLEN); + + /* + * Initialize the crypto templates. It's ok if this fails because + * this is just an optimization. + */ + mech.cm_type = crypto_mech2id(zio_crypt_table[crypt].ci_mechname); + ret = crypto_create_ctx_template(&mech, &key->zk_current_key, + &key->zk_current_tmpl, KM_SLEEP); + if (ret != CRYPTO_SUCCESS) + key->zk_current_tmpl = NULL; + + mech.cm_type = crypto_mech2id(SUN_CKM_SHA512_HMAC); + ret = crypto_create_ctx_template(&mech, &key->zk_hmac_key, + &key->zk_hmac_tmpl, KM_SLEEP); + if (ret != CRYPTO_SUCCESS) + key->zk_hmac_tmpl = NULL; + + key->zk_crypt = crypt; + key->zk_guid = guid; + key->zk_salt_count = 0; + rw_init(&key->zk_salt_lock, NULL, RW_DEFAULT, NULL); + + return (0); + +error: + zio_crypt_key_destroy(key); + return (ret); +} + +int +zio_crypt_generate_iv(uint8_t *ivbuf) +{ + int ret; + + /* randomly generate the IV */ + ret = random_get_pseudo_bytes(ivbuf, ZIO_DATA_IV_LEN); + if (ret != 0) + goto error; + + return (0); + +error: + bzero(ivbuf, ZIO_DATA_IV_LEN); + return (ret); +} + +int +zio_crypt_do_hmac(zio_crypt_key_t *key, uint8_t *data, uint_t datalen, + uint8_t *digestbuf) +{ + int ret; + crypto_mechanism_t mech; + crypto_data_t in_data, digest_data; + uint8_t raw_digestbuf[SHA512_DIGEST_LEN]; + + /* initialize sha512-hmac mechanism and crypto data */ + mech.cm_type = crypto_mech2id(SUN_CKM_SHA512_HMAC); + mech.cm_param = NULL; + mech.cm_param_len = 0; + + /* initialize the crypto data */ + in_data.cd_format = CRYPTO_DATA_RAW; + in_data.cd_offset = 0; + in_data.cd_length = datalen; + in_data.cd_raw.iov_base = (char *)data; + in_data.cd_raw.iov_len = in_data.cd_length; + + digest_data.cd_format = CRYPTO_DATA_RAW; + digest_data.cd_offset = 0; + digest_data.cd_length = SHA512_DIGEST_LEN; + digest_data.cd_raw.iov_base = (char *)raw_digestbuf; + digest_data.cd_raw.iov_len = digest_data.cd_length; + + /* generate the hmac */ + ret = crypto_mac(&mech, &in_data, &key->zk_hmac_key, key->zk_hmac_tmpl, + &digest_data, NULL); + if (ret != CRYPTO_SUCCESS) { + ret = SET_ERROR(EIO); + goto error; + } + + bcopy(raw_digestbuf, digestbuf, ZIO_DATA_MAC_LEN); + + return (0); + +error: + bzero(digestbuf, ZIO_DATA_MAC_LEN); + return (ret); +} + +int +zio_crypt_generate_iv_salt_dedup(zio_crypt_key_t *key, uint8_t *data, + uint_t datalen, uint8_t *ivbuf, uint8_t *salt) +{ + int ret; + uint8_t digestbuf[SHA512_DIGEST_LEN]; + + ret = zio_crypt_do_hmac(key, data, datalen, digestbuf); + if (ret != 0) + return (ret); + + bcopy(digestbuf, salt, ZIO_DATA_SALT_LEN); + bcopy(digestbuf + ZIO_DATA_SALT_LEN, ivbuf, ZIO_DATA_IV_LEN); + + return (0); +} + +/* + * The following functions are used to encode and decode encryption parameters + * into blkptr_t and zil_header_t. The ICP wants to use these parameters as + * byte strings, which normally means that these strings would not need to deal + * with byteswapping at all. However, both blkptr_t and zil_header_t may be + * byteswapped by lower layers and so we must "undo" that byteswap here upon + * decoding. + */ +void +zio_crypt_encode_params_bp(blkptr_t *bp, uint8_t *salt, uint8_t *iv) +{ + uint32_t val32; + + ASSERT(BP_IS_ENCRYPTED(bp)); + + bcopy(salt, &bp->blk_dva[2].dva_word[0], sizeof (uint64_t)); + bcopy(iv, &bp->blk_dva[2].dva_word[1], sizeof (uint64_t)); + bcopy(iv + sizeof (uint64_t), &val32, sizeof (uint32_t)); + BP_SET_IV2(bp, val32); +} + +void +zio_crypt_decode_params_bp(const blkptr_t *bp, uint8_t *salt, uint8_t *iv) +{ + uint64_t val64; + uint32_t val32; + + ASSERT(BP_IS_PROTECTED(bp)); + + /* for convenience, so callers don't need to check */ + if (BP_IS_AUTHENTICATED(bp)) { + bzero(salt, ZIO_DATA_SALT_LEN); + bzero(iv, ZIO_DATA_IV_LEN); + return; + } + + if (!BP_SHOULD_BYTESWAP(bp)) { + bcopy(&bp->blk_dva[2].dva_word[0], salt, sizeof (uint64_t)); + bcopy(&bp->blk_dva[2].dva_word[1], iv, sizeof (uint64_t)); + + val32 = (uint32_t)BP_GET_IV2(bp); + bcopy(&val32, iv + sizeof (uint64_t), sizeof (uint32_t)); + } else { + val64 = BSWAP_64(bp->blk_dva[2].dva_word[0]); + bcopy(&val64, salt, sizeof (uint64_t)); + + val64 = BSWAP_64(bp->blk_dva[2].dva_word[1]); + bcopy(&val64, iv, sizeof (uint64_t)); + + val32 = BSWAP_32((uint32_t)BP_GET_IV2(bp)); + bcopy(&val32, iv + sizeof (uint64_t), sizeof (uint32_t)); + } +} + +void +zio_crypt_encode_mac_bp(blkptr_t *bp, uint8_t *mac) +{ + ASSERT(BP_USES_CRYPT(bp)); + ASSERT3U(BP_GET_TYPE(bp), !=, DMU_OT_OBJSET); + + bcopy(mac, &bp->blk_cksum.zc_word[2], sizeof (uint64_t)); + bcopy(mac + sizeof (uint64_t), &bp->blk_cksum.zc_word[3], + sizeof (uint64_t)); +} + +void +zio_crypt_decode_mac_bp(const blkptr_t *bp, uint8_t *mac) +{ + uint64_t val64; + + ASSERT(BP_USES_CRYPT(bp) || BP_IS_HOLE(bp)); + + /* for convenience, so callers don't need to check */ + if (BP_GET_TYPE(bp) == DMU_OT_OBJSET) { + bzero(mac, ZIO_DATA_MAC_LEN); + return; + } + + if (!BP_SHOULD_BYTESWAP(bp)) { + bcopy(&bp->blk_cksum.zc_word[2], mac, sizeof (uint64_t)); + bcopy(&bp->blk_cksum.zc_word[3], mac + sizeof (uint64_t), + sizeof (uint64_t)); + } else { + val64 = BSWAP_64(bp->blk_cksum.zc_word[2]); + bcopy(&val64, mac, sizeof (uint64_t)); + + val64 = BSWAP_64(bp->blk_cksum.zc_word[3]); + bcopy(&val64, mac + sizeof (uint64_t), sizeof (uint64_t)); + } +} + +void +zio_crypt_encode_mac_zil(void *data, uint8_t *mac) +{ + zil_chain_t *zilc = data; + + bcopy(mac, &zilc->zc_eck.zec_cksum.zc_word[2], sizeof (uint64_t)); + bcopy(mac + sizeof (uint64_t), &zilc->zc_eck.zec_cksum.zc_word[3], + sizeof (uint64_t)); +} + +void +zio_crypt_decode_mac_zil(const void *data, uint8_t *mac) +{ + /* + * The ZIL MAC is embedded in the block it protects, which will + * not have been byteswapped by the time this function has been called. + * As a result, we don't need to worry about byteswapping the MAC. + */ + const zil_chain_t *zilc = data; + + bcopy(&zilc->zc_eck.zec_cksum.zc_word[2], mac, sizeof (uint64_t)); + bcopy(&zilc->zc_eck.zec_cksum.zc_word[3], mac + sizeof (uint64_t), + sizeof (uint64_t)); +} + +/* + * This routine takes a block of dnodes (src_abd) and copies only the bonus + * buffers to the same offsets in the dst buffer. datalen should be the size + * of both the src_abd and the dst buffer (not just the length of the bonus + * buffers). + */ +void +zio_crypt_copy_dnode_bonus(abd_t *src_abd, uint8_t *dst, uint_t datalen) +{ + uint_t i, max_dnp = datalen >> DNODE_SHIFT; + uint8_t *src; + dnode_phys_t *dnp, *sdnp, *ddnp; + + src = abd_borrow_buf_copy(src_abd, datalen); + + sdnp = (dnode_phys_t *)src; + ddnp = (dnode_phys_t *)dst; + + for (i = 0; i < max_dnp; i += sdnp[i].dn_extra_slots + 1) { + dnp = &sdnp[i]; + if (dnp->dn_type != DMU_OT_NONE && + DMU_OT_IS_ENCRYPTED(dnp->dn_bonustype) && + dnp->dn_bonuslen != 0) { + bcopy(DN_BONUS(dnp), DN_BONUS(&ddnp[i]), + DN_MAX_BONUS_LEN(dnp)); + } + } + + abd_return_buf(src_abd, src, datalen); +} + +static void +zio_crypt_bp_zero_nonportable_blkprop(blkptr_t *bp) +{ + BP_SET_DEDUP(bp, 0); + BP_SET_CHECKSUM(bp, 0); + + /* + * psize cannot be set to zero or it will trigger asserts, but the + * value doesn't really matter as long as it is constant. + */ + BP_SET_PSIZE(bp, SPA_MINBLOCKSIZE); +} + +static int +zio_crypt_bp_do_hmac_updates(crypto_context_t ctx, boolean_t should_bswap, + blkptr_t *bp) +{ + int ret; + crypto_data_t cd; + uint64_t le_blkprop; + blkptr_t tmpbp = *bp; + uint8_t mac[ZIO_DATA_MAC_LEN]; + + cd.cd_format = CRYPTO_DATA_RAW; + cd.cd_offset = 0; + + if (should_bswap) + byteswap_uint64_array(&tmpbp, sizeof (blkptr_t)); + + ASSERT(BP_USES_CRYPT(&tmpbp) || BP_IS_HOLE(&tmpbp)); + ASSERT0(BP_IS_EMBEDDED(&tmpbp)); + zio_crypt_bp_zero_nonportable_blkprop(&tmpbp); + + le_blkprop = (ZFS_HOST_BYTEORDER) ? + tmpbp.blk_prop : BSWAP_64(tmpbp.blk_prop); + + cd.cd_length = sizeof (uint64_t); + cd.cd_raw.iov_base = (char *)&le_blkprop; + cd.cd_raw.iov_len = cd.cd_length; + + ret = crypto_mac_update(ctx, &cd, NULL); + if (ret != CRYPTO_SUCCESS) { + ret = SET_ERROR(EIO); + goto error; + } + + zio_crypt_decode_mac_bp(&tmpbp, mac); + cd.cd_length = ZIO_DATA_MAC_LEN; + cd.cd_raw.iov_base = (char *)mac; + cd.cd_raw.iov_len = cd.cd_length; + + ret = crypto_mac_update(ctx, &cd, NULL); + if (ret != CRYPTO_SUCCESS) { + ret = SET_ERROR(EIO); + goto error; + } + + return (0); + +error: + return (ret); +} + +static void +zio_crypt_bp_do_indrect_checksum_updates(SHA2_CTX *ctx, boolean_t should_bswap, + blkptr_t *bp) +{ + blkptr_t tmpbp = *bp; + uint8_t mac[ZIO_DATA_MAC_LEN]; + + if (should_bswap) + byteswap_uint64_array(&tmpbp, sizeof (blkptr_t)); + + ASSERT(BP_USES_CRYPT(&tmpbp) || BP_IS_HOLE(&tmpbp)); + ASSERT0(BP_IS_EMBEDDED(&tmpbp)); + zio_crypt_bp_zero_nonportable_blkprop(&tmpbp); + zio_crypt_decode_mac_bp(&tmpbp, mac); + + if (should_bswap) + byteswap_uint64_array(&tmpbp, sizeof (blkptr_t)); + + SHA2Update(ctx, &tmpbp.blk_prop, sizeof (uint64_t)); + SHA2Update(ctx, mac, ZIO_DATA_MAC_LEN); +} + +static void +zio_crypt_bp_do_aad_updates(uint8_t **aadp, uint_t *aad_len, + boolean_t should_bswap, blkptr_t *bp) +{ + uint_t crypt_len; + blkptr_t tmpbp = *bp; + uint8_t mac[ZIO_DATA_MAC_LEN]; + + if (should_bswap) + byteswap_uint64_array(&tmpbp, sizeof (blkptr_t)); + + ASSERT(BP_USES_CRYPT(&tmpbp) || BP_IS_HOLE(&tmpbp)); + ASSERT0(BP_IS_EMBEDDED(&tmpbp)); + zio_crypt_bp_zero_nonportable_blkprop(&tmpbp); + zio_crypt_decode_mac_bp(&tmpbp, mac); + + if (should_bswap) + byteswap_uint64_array(&tmpbp, sizeof (blkptr_t)); + + crypt_len = sizeof (uint64_t); + bcopy(&tmpbp.blk_prop, *aadp, crypt_len); + *aadp += crypt_len; + *aad_len += crypt_len; + + crypt_len = ZIO_DATA_MAC_LEN; + bcopy(mac, *aadp, crypt_len); + *aadp += crypt_len; + *aad_len += crypt_len; +} + +static int +zio_crypt_do_dnode_hmac_updates(crypto_context_t ctx, boolean_t should_bswap, + dnode_phys_t *dnp) +{ + int ret, i; + dnode_phys_t *adnp; + boolean_t le_bswap = (should_bswap == ZFS_HOST_BYTEORDER); + crypto_data_t cd; + uint8_t tmp_dncore[offsetof(dnode_phys_t, dn_blkptr)]; + + cd.cd_format = CRYPTO_DATA_RAW; + cd.cd_offset = 0; + + /* authenticate the core dnode (masking out non-portable bits) */ + bcopy(dnp, tmp_dncore, sizeof (tmp_dncore)); + adnp = (dnode_phys_t *)tmp_dncore; + if (le_bswap) { + adnp->dn_datablkszsec = BSWAP_16(adnp->dn_datablkszsec); + adnp->dn_bonuslen = BSWAP_16(adnp->dn_bonuslen); + adnp->dn_maxblkid = BSWAP_64(adnp->dn_maxblkid); + adnp->dn_used = BSWAP_64(adnp->dn_used); + } + adnp->dn_flags &= DNODE_CRYPT_PORTABLE_FLAGS_MASK; + adnp->dn_used = 0; + + cd.cd_length = sizeof (tmp_dncore); + cd.cd_raw.iov_base = (char *)adnp; + cd.cd_raw.iov_len = cd.cd_length; + + ret = crypto_mac_update(ctx, &cd, NULL); + if (ret != CRYPTO_SUCCESS) { + ret = SET_ERROR(EIO); + goto error; + } + + for (i = 0; i < dnp->dn_nblkptr; i++) { + ret = zio_crypt_bp_do_hmac_updates(ctx, + should_bswap, &dnp->dn_blkptr[i]); + if (ret != 0) + goto error; + } + + if (dnp->dn_flags & DNODE_FLAG_SPILL_BLKPTR) { + ret = zio_crypt_bp_do_hmac_updates(ctx, + should_bswap, DN_SPILL_BLKPTR(dnp)); + if (ret != 0) + goto error; + } + + return (0); + +error: + return (ret); +} + +/* + * objset_phys_t blocks introduce a number of exceptions to the normal + * authentication process. objset_phys_t's contain 2 seperate HMACS for + * protecting the integrity of their data. The portable_mac protects the + * the metadnode. This MAC can be sent with a raw send and protects against + * reordering of data within the metadnode. The local_mac protects the user + * accounting objects which are not sent from one system to another. + * + * In addition, objset blocks are the only blocks that can be modified and + * written to disk without the key loaded under certain circumstances. During + * zil_claim() we need to be able to update the zil_header_t to complete + * claiming log blocks and during raw receives we need to write out the + * portable_mac from the send file. Both of these actions are possible + * because these fields are not protected by either MAC so neither one will + * need to modify the MACs without the key. However, when the modified blocks + * are written out they will be byteswapped into the host machine's native + * endianness which will modify fields protected by the MAC. As a result, MAC + * calculation for objset blocks works slightly differently from other block + * types. Where other block types MAC the data in whatever endianness is + * written to disk, objset blocks always MAC little endian version of their + * values. In the code, should_bswap is the value from BP_SHOULD_BYTESWAP() + * and le_bswap indicates whether a byteswap is needed to get this block + * into little endian format. + */ +int +zio_crypt_do_objset_hmacs(zio_crypt_key_t *key, void *data, uint_t datalen, + boolean_t should_bswap, uint8_t *portable_mac, uint8_t *local_mac) +{ + int ret; + crypto_mechanism_t mech; + crypto_context_t ctx; + crypto_data_t cd; + objset_phys_t *osp = data; + uint64_t intval; + boolean_t le_bswap = (should_bswap == ZFS_HOST_BYTEORDER); + uint8_t raw_portable_mac[SHA512_DIGEST_LEN]; + uint8_t raw_local_mac[SHA512_DIGEST_LEN]; + + /* initialize HMAC mechanism */ + mech.cm_type = crypto_mech2id(SUN_CKM_SHA512_HMAC); + mech.cm_param = NULL; + mech.cm_param_len = 0; + + cd.cd_format = CRYPTO_DATA_RAW; + cd.cd_offset = 0; + + /* calculate the portable MAC from the portable fields and metadnode */ + ret = crypto_mac_init(&mech, &key->zk_hmac_key, NULL, &ctx, NULL); + if (ret != CRYPTO_SUCCESS) { + ret = SET_ERROR(EIO); + goto error; + } + + /* add in the os_type */ + intval = (le_bswap) ? osp->os_type : BSWAP_64(osp->os_type); + cd.cd_length = sizeof (uint64_t); + cd.cd_raw.iov_base = (char *)&intval; + cd.cd_raw.iov_len = cd.cd_length; + + ret = crypto_mac_update(ctx, &cd, NULL); + if (ret != CRYPTO_SUCCESS) { + ret = SET_ERROR(EIO); + goto error; + } + + /* add in the portable os_flags */ + intval = osp->os_flags; + if (should_bswap) + intval = BSWAP_64(intval); + intval &= OBJSET_CRYPT_PORTABLE_FLAGS_MASK; + if (!ZFS_HOST_BYTEORDER) + intval = BSWAP_64(intval); + + cd.cd_length = sizeof (uint64_t); + cd.cd_raw.iov_base = (char *)&intval; + cd.cd_raw.iov_len = cd.cd_length; + + ret = crypto_mac_update(ctx, &cd, NULL); + if (ret != CRYPTO_SUCCESS) { + ret = SET_ERROR(EIO); + goto error; + } + + /* add in fields from the metadnode */ + ret = zio_crypt_do_dnode_hmac_updates(ctx, should_bswap, + &osp->os_meta_dnode); + if (ret) + goto error; + + /* store the final digest in a temporary buffer and copy what we need */ + cd.cd_length = SHA512_DIGEST_LEN; + cd.cd_raw.iov_base = (char *)raw_portable_mac; + cd.cd_raw.iov_len = cd.cd_length; + + ret = crypto_mac_final(ctx, &cd, NULL); + if (ret != CRYPTO_SUCCESS) { + ret = SET_ERROR(EIO); + goto error; + } + + bcopy(raw_portable_mac, portable_mac, ZIO_OBJSET_MAC_LEN); + + /* + * The local MAC protects the user and group accounting. If these + * objects are not present, the local MAC is zeroed out. + */ + if (osp->os_userused_dnode.dn_type == DMU_OT_NONE && + osp->os_userused_dnode.dn_type == DMU_OT_NONE) { + bzero(local_mac, ZIO_OBJSET_MAC_LEN); + return (0); + } + + /* calculate the local MAC from the userused and groupused dnodes */ + ret = crypto_mac_init(&mech, &key->zk_hmac_key, NULL, &ctx, NULL); + if (ret != CRYPTO_SUCCESS) { + ret = SET_ERROR(EIO); + goto error; + } + + /* add in the non-portable os_flags */ + intval = osp->os_flags; + if (should_bswap) + intval = BSWAP_64(intval); + intval &= ~OBJSET_CRYPT_PORTABLE_FLAGS_MASK; + if (!ZFS_HOST_BYTEORDER) + intval = BSWAP_64(intval); + + cd.cd_length = sizeof (uint64_t); + cd.cd_raw.iov_base = (char *)&intval; + cd.cd_raw.iov_len = cd.cd_length; + + ret = crypto_mac_update(ctx, &cd, NULL); + if (ret != CRYPTO_SUCCESS) { + ret = SET_ERROR(EIO); + goto error; + } + + /* add in fields from the user accounting dnodes */ + ret = zio_crypt_do_dnode_hmac_updates(ctx, should_bswap, + &osp->os_userused_dnode); + if (ret) + goto error; + + ret = zio_crypt_do_dnode_hmac_updates(ctx, should_bswap, + &osp->os_groupused_dnode); + if (ret) + goto error; + + /* store the final digest in a temporary buffer and copy what we need */ + cd.cd_length = SHA512_DIGEST_LEN; + cd.cd_raw.iov_base = (char *)raw_local_mac; + cd.cd_raw.iov_len = cd.cd_length; + + ret = crypto_mac_final(ctx, &cd, NULL); + if (ret != CRYPTO_SUCCESS) { + ret = SET_ERROR(EIO); + goto error; + } + + bcopy(raw_local_mac, local_mac, ZIO_OBJSET_MAC_LEN); + + return (0); + +error: + bzero(portable_mac, ZIO_OBJSET_MAC_LEN); + bzero(local_mac, ZIO_OBJSET_MAC_LEN); + return (ret); +} + +static void +zio_crypt_destroy_uio(uio_t *uio) +{ + if (uio->uio_iov) + kmem_free(uio->uio_iov, uio->uio_iovcnt * sizeof (iovec_t)); +} + +/* + * This function parses an uncompressed indirect block and returns a checksum + * of all the portable fields from all of the contained bps. The portable + * fields are the MAC and all of the fields from blk_prop except for the dedup, + * checksum, and psize bits. For an explanation of the purpose of this, see + * the comment block on object set authentication. + */ +int +zio_crypt_do_indirect_mac_checksum(boolean_t generate, void *buf, + uint_t datalen, boolean_t byteswap, uint8_t *cksum) +{ + blkptr_t *bp; + int i, epb = datalen >> SPA_BLKPTRSHIFT; + SHA2_CTX ctx; + uint8_t digestbuf[SHA512_DIGEST_LEN]; + + /* checksum all of the MACs from the layer below */ + SHA2Init(SHA512, &ctx); + for (i = 0, bp = buf; i < epb; i++, bp++) { + zio_crypt_bp_do_indrect_checksum_updates(&ctx, byteswap, bp); + } + SHA2Final(digestbuf, &ctx); + + if (generate) { + bcopy(digestbuf, cksum, ZIO_DATA_MAC_LEN); + return (0); + } + + if (bcmp(digestbuf, cksum, ZIO_DATA_MAC_LEN) != 0) + return (SET_ERROR(ECKSUM)); + + return (0); +} + +int +zio_crypt_do_indirect_mac_checksum_abd(boolean_t generate, abd_t *abd, + uint_t datalen, boolean_t byteswap, uint8_t *cksum) +{ + + int ret; + void *buf; + + buf = abd_borrow_buf_copy(abd, datalen); + ret = zio_crypt_do_indirect_mac_checksum(generate, buf, datalen, + byteswap, cksum); + abd_return_buf(abd, buf, datalen); + + return (ret); +} + +/* + * Special case handling routine for encrypting / decrypting ZIL blocks. + * We do not check for the older ZIL chain because the encryption feature + * was not available before the newer ZIL chain was introduced. The goal + * here is to encrypt everything except the blkptr_t of a lr_write_t and + * the zil_chain_t header. Everything that is not encrypted is authenticated. + */ +static int +zio_crypt_init_uios_zil(boolean_t encrypt, uint8_t *plainbuf, + uint8_t *cipherbuf, uint_t datalen, boolean_t byteswap, uio_t *puio, + uio_t *cuio, uint_t *enc_len, uint8_t **authbuf, uint_t *auth_len, + boolean_t *no_crypt) +{ + int ret; + uint64_t txtype; + uint_t nr_src, nr_dst, lr_len, crypt_len; + uint_t aad_len = 0, nr_iovecs = 0, total_len = 0; + iovec_t *src_iovecs = NULL, *dst_iovecs = NULL; + uint8_t *src, *dst, *slrp, *dlrp, *blkend, *aadp; + zil_chain_t *zilc; + lr_t *lr; + uint8_t *aadbuf = zio_buf_alloc(datalen); + + /* cipherbuf always needs an extra iovec for the MAC */ + if (encrypt) { + src = plainbuf; + dst = cipherbuf; + nr_src = 0; + nr_dst = 1; + } else { + src = cipherbuf; + dst = plainbuf; + nr_src = 1; + nr_dst = 0; + } + + /* find the start and end record of the log block */ + zilc = (zil_chain_t *)src; + slrp = src + sizeof (zil_chain_t); + aadp = aadbuf; + blkend = src + ((byteswap) ? BSWAP_64(zilc->zc_nused) : zilc->zc_nused); + + /* calculate the number of encrypted iovecs we will need */ + for (; slrp < blkend; slrp += lr_len) { + lr = (lr_t *)slrp; + + if (!byteswap) { + txtype = lr->lrc_txtype; + lr_len = lr->lrc_reclen; + } else { + txtype = BSWAP_64(lr->lrc_txtype); + lr_len = BSWAP_64(lr->lrc_reclen); + } + + nr_iovecs++; + if (txtype == TX_WRITE && lr_len != sizeof (lr_write_t)) + nr_iovecs++; + } + + nr_src += nr_iovecs; + nr_dst += nr_iovecs; + + /* allocate the iovec arrays */ + if (nr_src != 0) { + src_iovecs = kmem_alloc(nr_src * sizeof (iovec_t), KM_SLEEP); + if (!src_iovecs) { + ret = SET_ERROR(ENOMEM); + goto error; + } + } + + if (nr_dst != 0) { + dst_iovecs = kmem_alloc(nr_dst * sizeof (iovec_t), KM_SLEEP); + if (!dst_iovecs) { + ret = SET_ERROR(ENOMEM); + goto error; + } + } + + /* + * Copy the plain zil header over and authenticate everything except + * the checksum that will store our MAC. If we are writing the data + * the embedded checksum will not have been calculated yet, so we don't + * authenticate that. + */ + bcopy(src, dst, sizeof (zil_chain_t)); + bcopy(src, aadp, sizeof (zil_chain_t) - sizeof (zio_eck_t)); + aadp += sizeof (zil_chain_t) - sizeof (zio_eck_t); + aad_len += sizeof (zil_chain_t) - sizeof (zio_eck_t); + + /* loop over records again, filling in iovecs */ + nr_iovecs = 0; + slrp = src + sizeof (zil_chain_t); + dlrp = dst + sizeof (zil_chain_t); + + for (; slrp < blkend; slrp += lr_len, dlrp += lr_len) { + lr = (lr_t *)slrp; + + if (!byteswap) { + txtype = lr->lrc_txtype; + lr_len = lr->lrc_reclen; + } else { + txtype = BSWAP_64(lr->lrc_txtype); + lr_len = BSWAP_64(lr->lrc_reclen); + } + + /* copy the common lr_t */ + bcopy(slrp, dlrp, sizeof (lr_t)); + bcopy(slrp, aadp, sizeof (lr_t)); + aadp += sizeof (lr_t); + aad_len += sizeof (lr_t); + + /* + * If this is a TX_WRITE record we want to encrypt everything + * except the bp if exists. If the bp does exist we want to + * authenticate it. + */ + if (txtype == TX_WRITE) { + crypt_len = sizeof (lr_write_t) - + sizeof (lr_t) - sizeof (blkptr_t); + src_iovecs[nr_iovecs].iov_base = slrp + sizeof (lr_t); + src_iovecs[nr_iovecs].iov_len = crypt_len; + dst_iovecs[nr_iovecs].iov_base = dlrp + sizeof (lr_t); + dst_iovecs[nr_iovecs].iov_len = crypt_len; + + /* copy the bp now since it will not be encrypted */ + bcopy(slrp + sizeof (lr_write_t) - sizeof (blkptr_t), + dlrp + sizeof (lr_write_t) - sizeof (blkptr_t), + sizeof (blkptr_t)); + bcopy(slrp + sizeof (lr_write_t) - sizeof (blkptr_t), + aadp, sizeof (blkptr_t)); + aadp += sizeof (blkptr_t); + aad_len += sizeof (blkptr_t); + nr_iovecs++; + total_len += crypt_len; + + if (lr_len != sizeof (lr_write_t)) { + crypt_len = lr_len - sizeof (lr_write_t); + src_iovecs[nr_iovecs].iov_base = + slrp + sizeof (lr_write_t); + src_iovecs[nr_iovecs].iov_len = crypt_len; + dst_iovecs[nr_iovecs].iov_base = + dlrp + sizeof (lr_write_t); + dst_iovecs[nr_iovecs].iov_len = crypt_len; + nr_iovecs++; + total_len += crypt_len; + } + } else { + crypt_len = lr_len - sizeof (lr_t); + src_iovecs[nr_iovecs].iov_base = slrp + sizeof (lr_t); + src_iovecs[nr_iovecs].iov_len = crypt_len; + dst_iovecs[nr_iovecs].iov_base = dlrp + sizeof (lr_t); + dst_iovecs[nr_iovecs].iov_len = crypt_len; + nr_iovecs++; + total_len += crypt_len; + } + } + + *no_crypt = (nr_iovecs == 0); + *enc_len = total_len; + *authbuf = aadbuf; + *auth_len = aad_len; + + if (encrypt) { + puio->uio_iov = src_iovecs; + puio->uio_iovcnt = nr_src; + cuio->uio_iov = dst_iovecs; + cuio->uio_iovcnt = nr_dst; + } else { + puio->uio_iov = dst_iovecs; + puio->uio_iovcnt = nr_dst; + cuio->uio_iov = src_iovecs; + cuio->uio_iovcnt = nr_src; + } + + return (0); + +error: + zio_buf_free(aadbuf, datalen); + if (src_iovecs != NULL) + kmem_free(src_iovecs, nr_src * sizeof (iovec_t)); + if (dst_iovecs != NULL) + kmem_free(dst_iovecs, nr_dst * sizeof (iovec_t)); + + *enc_len = 0; + *authbuf = NULL; + *auth_len = 0; + *no_crypt = B_FALSE; + puio->uio_iov = NULL; + puio->uio_iovcnt = 0; + cuio->uio_iov = NULL; + cuio->uio_iovcnt = 0; + return (ret); +} + +/* + * Special case handling routine for encrypting / decrypting dnode blocks. + */ +static int +zio_crypt_init_uios_dnode(boolean_t encrypt, uint8_t *plainbuf, + uint8_t *cipherbuf, uint_t datalen, boolean_t byteswap, uio_t *puio, + uio_t *cuio, uint_t *enc_len, uint8_t **authbuf, uint_t *auth_len, + boolean_t *no_crypt) +{ + int ret; + uint_t nr_src, nr_dst, crypt_len; + uint_t aad_len = 0, nr_iovecs = 0, total_len = 0; + uint_t i, j, max_dnp = datalen >> DNODE_SHIFT; + iovec_t *src_iovecs = NULL, *dst_iovecs = NULL; + uint8_t *src, *dst, *aadp; + dnode_phys_t *dnp, *adnp, *sdnp, *ddnp; + uint8_t *aadbuf = zio_buf_alloc(datalen); + + if (encrypt) { + src = plainbuf; + dst = cipherbuf; + nr_src = 0; + nr_dst = 1; + } else { + src = cipherbuf; + dst = plainbuf; + nr_src = 1; + nr_dst = 0; + } + + sdnp = (dnode_phys_t *)src; + ddnp = (dnode_phys_t *)dst; + aadp = aadbuf; + + /* + * Count the number of iovecs we will need to do the encryption by + * counting the number of bonus buffers that need to be encrypted. + */ + for (i = 0; i < max_dnp; i += sdnp[i].dn_extra_slots + 1) { + /* + * This block may still be byteswapped. However, all of the + * values we use are either uint8_t's (for which byteswapping + * is a noop) or a * != 0 check, which will work regardless + * of whether or not we byteswap. + */ + if (sdnp[i].dn_type != DMU_OT_NONE && + DMU_OT_IS_ENCRYPTED(sdnp[i].dn_bonustype) && + sdnp[i].dn_bonuslen != 0) { + nr_iovecs++; + } + } + + nr_src += nr_iovecs; + nr_dst += nr_iovecs; + + if (nr_src != 0) { + src_iovecs = kmem_alloc(nr_src * sizeof (iovec_t), KM_SLEEP); + if (!src_iovecs) { + ret = SET_ERROR(ENOMEM); + goto error; + } + } + + if (nr_dst != 0) { + dst_iovecs = kmem_alloc(nr_dst * sizeof (iovec_t), KM_SLEEP); + if (!dst_iovecs) { + ret = SET_ERROR(ENOMEM); + goto error; + } + } + + nr_iovecs = 0; + + /* + * Iterate through the dnodes again, this time filling in the uios + * we allocated earlier. We also concatenate any data we want to + * authenticate onto aadbuf. + */ + for (i = 0; i < max_dnp; i += sdnp[i].dn_extra_slots + 1) { + dnp = &sdnp[i]; + + /* copy over the core fields and blkptrs (kept as plaintext) */ + bcopy(dnp, &ddnp[i], (uint8_t *)DN_BONUS(dnp) - (uint8_t *)dnp); + + if (dnp->dn_flags & DNODE_FLAG_SPILL_BLKPTR) { + bcopy(DN_SPILL_BLKPTR(dnp), DN_SPILL_BLKPTR(&ddnp[i]), + sizeof (blkptr_t)); + } + + /* + * Handle authenticated data. We authenticate everything in + * the dnode that can be brought over when we do a raw send. + * This includes all of the core fields as well as the MACs + * stored in the bp checksums and all of the portable bits + * from blk_prop. We include the dnode padding here in case it + * ever gets used in the future. Some dn_flags and dn_used are + * not portable so we mask those out values out of the + * authenticated data. + */ + crypt_len = offsetof(dnode_phys_t, dn_blkptr); + bcopy(dnp, aadp, crypt_len); + adnp = (dnode_phys_t *)aadp; + adnp->dn_flags &= DNODE_CRYPT_PORTABLE_FLAGS_MASK; + adnp->dn_used = 0; + aadp += crypt_len; + aad_len += crypt_len; + + for (j = 0; j < dnp->dn_nblkptr; j++) { + zio_crypt_bp_do_aad_updates(&aadp, &aad_len, + byteswap, &dnp->dn_blkptr[j]); + } + + if (dnp->dn_flags & DNODE_FLAG_SPILL_BLKPTR) { + zio_crypt_bp_do_aad_updates(&aadp, &aad_len, + byteswap, DN_SPILL_BLKPTR(dnp)); + } + + /* + * If this bonus buffer needs to be encrypted, we prepare an + * iovec_t. The encryption / decryption functions will fill + * this in for us with the encrypted or decrypted data. + * Otherwise we add the bonus buffer to the authenticated + * data buffer and copy it over to the destination. The + * encrypted iovec extends to DN_MAX_BONUS_LEN(dnp) so that + * we can guarantee alignment with the AES block size + * (128 bits). + */ + crypt_len = DN_MAX_BONUS_LEN(dnp); + if (dnp->dn_type != DMU_OT_NONE && + DMU_OT_IS_ENCRYPTED(dnp->dn_bonustype) && + dnp->dn_bonuslen != 0) { + src_iovecs[nr_iovecs].iov_base = DN_BONUS(dnp); + src_iovecs[nr_iovecs].iov_len = crypt_len; + dst_iovecs[nr_iovecs].iov_base = DN_BONUS(&ddnp[i]); + dst_iovecs[nr_iovecs].iov_len = crypt_len; + + nr_iovecs++; + total_len += crypt_len; + } else { + bcopy(DN_BONUS(dnp), DN_BONUS(&ddnp[i]), crypt_len); + bcopy(DN_BONUS(dnp), aadp, crypt_len); + aadp += crypt_len; + aad_len += crypt_len; + } + } + + *no_crypt = (nr_iovecs == 0); + *enc_len = total_len; + *authbuf = aadbuf; + *auth_len = aad_len; + + if (encrypt) { + puio->uio_iov = src_iovecs; + puio->uio_iovcnt = nr_src; + cuio->uio_iov = dst_iovecs; + cuio->uio_iovcnt = nr_dst; + } else { + puio->uio_iov = dst_iovecs; + puio->uio_iovcnt = nr_dst; + cuio->uio_iov = src_iovecs; + cuio->uio_iovcnt = nr_src; + } + + return (0); + +error: + zio_buf_free(aadbuf, datalen); + if (src_iovecs != NULL) + kmem_free(src_iovecs, nr_src * sizeof (iovec_t)); + if (dst_iovecs != NULL) + kmem_free(dst_iovecs, nr_dst * sizeof (iovec_t)); + + *enc_len = 0; + *authbuf = NULL; + *auth_len = 0; + *no_crypt = B_FALSE; + puio->uio_iov = NULL; + puio->uio_iovcnt = 0; + cuio->uio_iov = NULL; + cuio->uio_iovcnt = 0; + return (ret); +} + +static int +zio_crypt_init_uios_normal(boolean_t encrypt, uint8_t *plainbuf, + uint8_t *cipherbuf, uint_t datalen, uio_t *puio, uio_t *cuio, + uint_t *enc_len) +{ + int ret; + uint_t nr_plain = 1, nr_cipher = 2; + iovec_t *plain_iovecs = NULL, *cipher_iovecs = NULL; + + /* allocate the iovecs for the plain and cipher data */ + plain_iovecs = kmem_alloc(nr_plain * sizeof (iovec_t), + KM_SLEEP); + if (!plain_iovecs) { + ret = SET_ERROR(ENOMEM); + goto error; + } + + cipher_iovecs = kmem_alloc(nr_cipher * sizeof (iovec_t), + KM_SLEEP); + if (!cipher_iovecs) { + ret = SET_ERROR(ENOMEM); + goto error; + } + + plain_iovecs[0].iov_base = plainbuf; + plain_iovecs[0].iov_len = datalen; + cipher_iovecs[0].iov_base = cipherbuf; + cipher_iovecs[0].iov_len = datalen; + + *enc_len = datalen; + puio->uio_iov = plain_iovecs; + puio->uio_iovcnt = nr_plain; + cuio->uio_iov = cipher_iovecs; + cuio->uio_iovcnt = nr_cipher; + + return (0); + +error: + if (plain_iovecs != NULL) + kmem_free(plain_iovecs, nr_plain * sizeof (iovec_t)); + if (cipher_iovecs != NULL) + kmem_free(cipher_iovecs, nr_cipher * sizeof (iovec_t)); + + *enc_len = 0; + puio->uio_iov = NULL; + puio->uio_iovcnt = 0; + cuio->uio_iov = NULL; + cuio->uio_iovcnt = 0; + return (ret); +} + +/* + * This function builds up the plaintext (puio) and ciphertext (cuio) uios so + * that they can be used for encryption and decryption by zio_do_crypt_uio(). + * Most blocks will use zio_crypt_init_uios_normal(), with ZIL and dnode blocks + * requiring special handling to parse out pieces that are to be encrypted. The + * authbuf is used by these special cases to store additional authenticated + * data (AAD) for the encryption modes. + */ +static int +zio_crypt_init_uios(boolean_t encrypt, dmu_object_type_t ot, uint8_t *plainbuf, + uint8_t *cipherbuf, uint_t datalen, boolean_t byteswap, uint8_t *mac, + uio_t *puio, uio_t *cuio, uint_t *enc_len, uint8_t **authbuf, + uint_t *auth_len, boolean_t *no_crypt) +{ + int ret; + iovec_t *mac_iov; + + ASSERT(DMU_OT_IS_ENCRYPTED(ot) || ot == DMU_OT_NONE); + + /* route to handler */ + switch (ot) { + case DMU_OT_INTENT_LOG: + ret = zio_crypt_init_uios_zil(encrypt, plainbuf, cipherbuf, + datalen, byteswap, puio, cuio, enc_len, authbuf, auth_len, + no_crypt); + break; + case DMU_OT_DNODE: + ret = zio_crypt_init_uios_dnode(encrypt, plainbuf, cipherbuf, + datalen, byteswap, puio, cuio, enc_len, authbuf, auth_len, + no_crypt); + break; + default: + ret = zio_crypt_init_uios_normal(encrypt, plainbuf, cipherbuf, + datalen, puio, cuio, enc_len); + *authbuf = NULL; + *auth_len = 0; + *no_crypt = B_FALSE; + break; + } + + if (ret != 0) + goto error; + + /* populate the uios */ + puio->uio_segflg = UIO_SYSSPACE; + cuio->uio_segflg = UIO_SYSSPACE; + + mac_iov = ((iovec_t *)&cuio->uio_iov[cuio->uio_iovcnt - 1]); + mac_iov->iov_base = mac; + mac_iov->iov_len = ZIO_DATA_MAC_LEN; + + return (0); + +error: + return (ret); +} + +/* + * Primary encryption / decryption entrypoint for zio data. + */ +int +zio_do_crypt_data(boolean_t encrypt, zio_crypt_key_t *key, uint8_t *salt, + dmu_object_type_t ot, uint8_t *iv, uint8_t *mac, uint_t datalen, + boolean_t byteswap, uint8_t *plainbuf, uint8_t *cipherbuf, + boolean_t *no_crypt) +{ + int ret; + boolean_t locked = B_FALSE; + uint64_t crypt = key->zk_crypt; + uint_t keydata_len = zio_crypt_table[crypt].ci_keylen; + uint_t enc_len, auth_len; + uio_t puio, cuio; + uint8_t enc_keydata[MASTER_KEY_MAX_LEN]; + crypto_key_t tmp_ckey, *ckey = NULL; + crypto_ctx_template_t tmpl; + uint8_t *authbuf = NULL; + + bzero(&puio, sizeof (uio_t)); + bzero(&cuio, sizeof (uio_t)); + + /* create uios for encryption */ + ret = zio_crypt_init_uios(encrypt, ot, plainbuf, cipherbuf, datalen, + byteswap, mac, &puio, &cuio, &enc_len, &authbuf, &auth_len, + no_crypt); + if (ret != 0) + return (ret); + + /* + * If the needed key is the current one, just use it. Otherwise we + * need to generate a temporary one from the given salt + master key. + * If we are encrypting, we must return a copy of the current salt + * so that it can be stored in the blkptr_t. + */ + rw_enter(&key->zk_salt_lock, RW_READER); + locked = B_TRUE; + + if (bcmp(salt, key->zk_salt, ZIO_DATA_SALT_LEN) == 0) { + ckey = &key->zk_current_key; + tmpl = key->zk_current_tmpl; + } else { + rw_exit(&key->zk_salt_lock); + locked = B_FALSE; + + ret = hkdf_sha512(key->zk_master_keydata, keydata_len, NULL, 0, + salt, ZIO_DATA_SALT_LEN, enc_keydata, keydata_len); + if (ret != 0) + goto error; + + tmp_ckey.ck_format = CRYPTO_KEY_RAW; + tmp_ckey.ck_data = enc_keydata; + tmp_ckey.ck_length = BYTES_TO_BITS(keydata_len); + + ckey = &tmp_ckey; + tmpl = NULL; + } + + /* perform the encryption / decryption */ + ret = zio_do_crypt_uio(encrypt, key->zk_crypt, ckey, tmpl, iv, enc_len, + &puio, &cuio, authbuf, auth_len); + if (ret != 0) + goto error; + + if (locked) { + rw_exit(&key->zk_salt_lock); + locked = B_FALSE; + } + + if (authbuf != NULL) + zio_buf_free(authbuf, datalen); + if (ckey == &tmp_ckey) + bzero(enc_keydata, keydata_len); + zio_crypt_destroy_uio(&puio); + zio_crypt_destroy_uio(&cuio); + + return (0); + +error: + if (locked) + rw_exit(&key->zk_salt_lock); + if (authbuf != NULL) + zio_buf_free(authbuf, datalen); + if (ckey == &tmp_ckey) + bzero(enc_keydata, keydata_len); + zio_crypt_destroy_uio(&puio); + zio_crypt_destroy_uio(&cuio); + + return (ret); +} + +/* + * Simple wrapper around zio_do_crypt_data() to work with abd's instead of + * linear buffers. + */ +int +zio_do_crypt_abd(boolean_t encrypt, zio_crypt_key_t *key, uint8_t *salt, + dmu_object_type_t ot, uint8_t *iv, uint8_t *mac, uint_t datalen, + boolean_t byteswap, abd_t *pabd, abd_t *cabd, boolean_t *no_crypt) +{ + int ret; + void *ptmp, *ctmp; + + if (encrypt) { + ptmp = abd_borrow_buf_copy(pabd, datalen); + ctmp = abd_borrow_buf(cabd, datalen); + } else { + ptmp = abd_borrow_buf(pabd, datalen); + ctmp = abd_borrow_buf_copy(cabd, datalen); + } + + ret = zio_do_crypt_data(encrypt, key, salt, ot, iv, mac, + datalen, byteswap, ptmp, ctmp, no_crypt); + if (ret != 0) + goto error; + + if (encrypt) { + abd_return_buf(pabd, ptmp, datalen); + abd_return_buf_copy(cabd, ctmp, datalen); + } else { + abd_return_buf_copy(pabd, ptmp, datalen); + abd_return_buf(cabd, ctmp, datalen); + } + + return (0); + +error: + if (encrypt) { + abd_return_buf(pabd, ptmp, datalen); + abd_return_buf_copy(cabd, ctmp, datalen); + } else { + abd_return_buf_copy(pabd, ptmp, datalen); + abd_return_buf(cabd, ctmp, datalen); + } + + return (ret); +} + +#if defined(_KERNEL) && defined(HAVE_SPL) +/* BEGIN CSTYLED */ +module_param(zfs_key_max_salt_uses, ulong, 0644); +MODULE_PARM_DESC(zfs_key_max_salt_uses, "Max number of times a salt value " + "can be used for generating encryption keys before it is rotated"); +/* END CSTYLED */ +#endif |