diff options
Diffstat (limited to 'crypto/block.c')
| -rw-r--r-- | crypto/block.c | 258 |
1 files changed, 258 insertions, 0 deletions
diff --git a/crypto/block.c b/crypto/block.c new file mode 100644 index 0000000000..3c27ef0e8a --- /dev/null +++ b/crypto/block.c @@ -0,0 +1,258 @@ +/* + * QEMU Crypto block device encryption + * + * Copyright (c) 2015-2016 Red Hat, Inc. + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2 of the License, or (at your option) any later version. + * + * This library is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this library; if not, see <http://www.gnu.org/licenses/>. + * + */ + +#include "qemu/osdep.h" +#include "crypto/blockpriv.h" +#include "crypto/block-qcow.h" + +static const QCryptoBlockDriver *qcrypto_block_drivers[] = { + [Q_CRYPTO_BLOCK_FORMAT_QCOW] = &qcrypto_block_driver_qcow, +}; + + +bool qcrypto_block_has_format(QCryptoBlockFormat format, + const uint8_t *buf, + size_t len) +{ + const QCryptoBlockDriver *driver; + + if (format >= G_N_ELEMENTS(qcrypto_block_drivers) || + !qcrypto_block_drivers[format]) { + return false; + } + + driver = qcrypto_block_drivers[format]; + + return driver->has_format(buf, len); +} + + +QCryptoBlock *qcrypto_block_open(QCryptoBlockOpenOptions *options, + QCryptoBlockReadFunc readfunc, + void *opaque, + unsigned int flags, + Error **errp) +{ + QCryptoBlock *block = g_new0(QCryptoBlock, 1); + + block->format = options->format; + + if (options->format >= G_N_ELEMENTS(qcrypto_block_drivers) || + !qcrypto_block_drivers[options->format]) { + error_setg(errp, "Unsupported block driver %d", options->format); + g_free(block); + return NULL; + } + + block->driver = qcrypto_block_drivers[options->format]; + + if (block->driver->open(block, options, + readfunc, opaque, flags, errp) < 0) { + g_free(block); + return NULL; + } + + return block; +} + + +QCryptoBlock *qcrypto_block_create(QCryptoBlockCreateOptions *options, + QCryptoBlockInitFunc initfunc, + QCryptoBlockWriteFunc writefunc, + void *opaque, + Error **errp) +{ + QCryptoBlock *block = g_new0(QCryptoBlock, 1); + + block->format = options->format; + + if (options->format >= G_N_ELEMENTS(qcrypto_block_drivers) || + !qcrypto_block_drivers[options->format]) { + error_setg(errp, "Unsupported block driver %d", options->format); + g_free(block); + return NULL; + } + + block->driver = qcrypto_block_drivers[options->format]; + + if (block->driver->create(block, options, initfunc, + writefunc, opaque, errp) < 0) { + g_free(block); + return NULL; + } + + return block; +} + + +int qcrypto_block_decrypt(QCryptoBlock *block, + uint64_t startsector, + uint8_t *buf, + size_t len, + Error **errp) +{ + return block->driver->decrypt(block, startsector, buf, len, errp); +} + + +int qcrypto_block_encrypt(QCryptoBlock *block, + uint64_t startsector, + uint8_t *buf, + size_t len, + Error **errp) +{ + return block->driver->encrypt(block, startsector, buf, len, errp); +} + + +QCryptoCipher *qcrypto_block_get_cipher(QCryptoBlock *block) +{ + return block->cipher; +} + + +QCryptoIVGen *qcrypto_block_get_ivgen(QCryptoBlock *block) +{ + return block->ivgen; +} + + +QCryptoHashAlgorithm qcrypto_block_get_kdf_hash(QCryptoBlock *block) +{ + return block->kdfhash; +} + + +uint64_t qcrypto_block_get_payload_offset(QCryptoBlock *block) +{ + return block->payload_offset; +} + + +void qcrypto_block_free(QCryptoBlock *block) +{ + if (!block) { + return; + } + + block->driver->cleanup(block); + + qcrypto_cipher_free(block->cipher); + qcrypto_ivgen_free(block->ivgen); + g_free(block); +} + + +int qcrypto_block_decrypt_helper(QCryptoCipher *cipher, + size_t niv, + QCryptoIVGen *ivgen, + int sectorsize, + uint64_t startsector, + uint8_t *buf, + size_t len, + Error **errp) +{ + uint8_t *iv; + int ret = -1; + + iv = niv ? g_new0(uint8_t, niv) : NULL; + + while (len > 0) { + size_t nbytes; + if (niv) { + if (qcrypto_ivgen_calculate(ivgen, + startsector, + iv, niv, + errp) < 0) { + goto cleanup; + } + + if (qcrypto_cipher_setiv(cipher, + iv, niv, + errp) < 0) { + goto cleanup; + } + } + + nbytes = len > sectorsize ? sectorsize : len; + if (qcrypto_cipher_decrypt(cipher, buf, buf, + nbytes, errp) < 0) { + goto cleanup; + } + + startsector++; + buf += nbytes; + len -= nbytes; + } + + ret = 0; + cleanup: + g_free(iv); + return ret; +} + + +int qcrypto_block_encrypt_helper(QCryptoCipher *cipher, + size_t niv, + QCryptoIVGen *ivgen, + int sectorsize, + uint64_t startsector, + uint8_t *buf, + size_t len, + Error **errp) +{ + uint8_t *iv; + int ret = -1; + + iv = niv ? g_new0(uint8_t, niv) : NULL; + + while (len > 0) { + size_t nbytes; + if (niv) { + if (qcrypto_ivgen_calculate(ivgen, + startsector, + iv, niv, + errp) < 0) { + goto cleanup; + } + + if (qcrypto_cipher_setiv(cipher, + iv, niv, + errp) < 0) { + goto cleanup; + } + } + + nbytes = len > sectorsize ? sectorsize : len; + if (qcrypto_cipher_encrypt(cipher, buf, buf, + nbytes, errp) < 0) { + goto cleanup; + } + + startsector++; + buf += nbytes; + len -= nbytes; + } + + ret = 0; + cleanup: + g_free(iv); + return ret; +} |