diff options
author | Peter Maydell <peter.maydell@linaro.org> | 2016-03-17 16:57:50 +0000 |
---|---|---|
committer | Peter Maydell <peter.maydell@linaro.org> | 2016-03-17 16:57:50 +0000 |
commit | 879c26fb9fd950eefcac64cc854b22edc05e317a (patch) | |
tree | d9c693d73fd7343b03ac1b7a186b7e8245ade232 /include | |
parent | 6741d38ad0f2405a6e999ebc9550801b01aca479 (diff) | |
parent | 3e308f20edfd65a21c98eb2d8079dacd47957444 (diff) |
Merge remote-tracking branch 'remotes/berrange/tags/pull-qcrypto-2016-03-17-3' into staging
Merge QCrypto 2016/03/17 v3
# gpg: Signature made Thu 17 Mar 2016 16:51:32 GMT using RSA key ID 15104FDF
# gpg: Good signature from "Daniel P. Berrange <dan@berrange.com>"
# gpg: aka "Daniel P. Berrange <berrange@redhat.com>"
* remotes/berrange/tags/pull-qcrypto-2016-03-17-3:
crypto: implement the LUKS block encryption format
crypto: add block encryption framework
crypto: wire up XTS mode for cipher APIs
crypto: refactor code for dealing with AES cipher
crypto: import an implementation of the XTS cipher mode
crypto: add support for the twofish cipher algorithm
crypto: add support for the serpent cipher algorithm
crypto: add support for the cast5-128 cipher algorithm
crypto: skip testing of unsupported cipher algorithms
crypto: add support for anti-forensic split algorithm
crypto: add support for generating initialization vectors
crypto: add support for PBKDF2 algorithm
crypto: add cryptographic random byte source
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Diffstat (limited to 'include')
-rw-r--r-- | include/crypto/afsplit.h | 135 | ||||
-rw-r--r-- | include/crypto/block.h | 232 | ||||
-rw-r--r-- | include/crypto/ivgen.h | 206 | ||||
-rw-r--r-- | include/crypto/pbkdf.h | 152 | ||||
-rw-r--r-- | include/crypto/random.h | 44 | ||||
-rw-r--r-- | include/crypto/xts.h | 86 |
6 files changed, 855 insertions, 0 deletions
diff --git a/include/crypto/afsplit.h b/include/crypto/afsplit.h new file mode 100644 index 0000000000..4cc4ca4b38 --- /dev/null +++ b/include/crypto/afsplit.h @@ -0,0 +1,135 @@ +/* + * QEMU Crypto anti forensic information splitter + * + * 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 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/>. + * + */ + +#ifndef QCRYPTO_AFSPLIT_H__ +#define QCRYPTO_AFSPLIT_H__ + +#include "crypto/hash.h" + +/** + * This module implements the anti-forensic splitter that is specified + * as part of the LUKS format: + * + * http://clemens.endorphin.org/cryptography + * http://clemens.endorphin.org/TKS1-draft.pdf + * + * The core idea is to take a short piece of data (key material) + * and process it to expand it to a much larger piece of data. + * The expansion process is reversible, to obtain the original + * short data. The key property of the expansion is that if any + * byte in the larger data set is changed / missing, it should be + * impossible to recreate the original short data. + * + * <example> + * <title>Creating a large split key for storage</title> + * <programlisting> + * size_t nkey = 32; + * uint32_t stripes = 32768; // To produce a 1 MB split key + * uint8_t *masterkey = ....a 32-byte AES key... + * uint8_t *splitkey; + * + * splitkey = g_new0(uint8_t, nkey * stripes); + * + * if (qcrypto_afsplit_encode(QCRYPTO_HASH_ALG_SHA256, + * nkey, stripes, + * masterkey, splitkey, errp) < 0) { + * g_free(splitkey); + * g_free(masterkey); + * return -1; + * } + * + * ...store splitkey somewhere... + * + * g_free(splitkey); + * g_free(masterkey); + * </programlisting> + * </example> + * + * <example> + * <title>Retrieving a master key from storage</title> + * <programlisting> + * size_t nkey = 32; + * uint32_t stripes = 32768; // To produce a 1 MB split key + * uint8_t *masterkey; + * uint8_t *splitkey = .... read in 1 MB of data... + * + * masterkey = g_new0(uint8_t, nkey); + * + * if (qcrypto_afsplit_decode(QCRYPTO_HASH_ALG_SHA256, + * nkey, stripes, + * splitkey, masterkey, errp) < 0) { + * g_free(splitkey); + * g_free(masterkey); + * return -1; + * } + * + * ..decrypt data with masterkey... + * + * g_free(splitkey); + * g_free(masterkey); + * </programlisting> + * </example> + */ + +/** + * qcrypto_afsplit_encode: + * @hash: the hash algorithm to use for data expansion + * @blocklen: the size of @in in bytes + * @stripes: the number of times to expand @in in size + * @in: the master key to be expanded in size + * @out: preallocated buffer to hold the split key + * @errp: pointer to a NULL-initialized error object + * + * Split the data in @in, which is @blocklen bytes in + * size, to form a larger piece of data @out, which is + * @blocklen * @stripes bytes in size. + * + * Returns: 0 on success, -1 on error; + */ +int qcrypto_afsplit_encode(QCryptoHashAlgorithm hash, + size_t blocklen, + uint32_t stripes, + const uint8_t *in, + uint8_t *out, + Error **errp); + +/** + * qcrypto_afsplit_decode: + * @hash: the hash algorithm to use for data compression + * @blocklen: the size of @out in bytes + * @stripes: the number of times to decrease @in in size + * @in: the split key to be recombined + * @out: preallocated buffer to hold the master key + * @errp: pointer to a NULL-initialized error object + * + * Join the data in @in, which is @blocklen * @stripes + * bytes in size, to form the original small piece of + * data @out, which is @blocklen bytes in size. + * + * Returns: 0 on success, -1 on error; + */ +int qcrypto_afsplit_decode(QCryptoHashAlgorithm hash, + size_t blocklen, + uint32_t stripes, + const uint8_t *in, + uint8_t *out, + Error **errp); + +#endif /* QCRYPTO_AFSPLIT_H__ */ diff --git a/include/crypto/block.h b/include/crypto/block.h new file mode 100644 index 0000000000..a21e11ff86 --- /dev/null +++ b/include/crypto/block.h @@ -0,0 +1,232 @@ +/* + * 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/>. + * + */ + +#ifndef QCRYPTO_BLOCK_H__ +#define QCRYPTO_BLOCK_H__ + +#include "crypto/cipher.h" +#include "crypto/ivgen.h" + +typedef struct QCryptoBlock QCryptoBlock; + +/* See also QCryptoBlockFormat, QCryptoBlockCreateOptions + * and QCryptoBlockOpenOptions in qapi/crypto.json */ + +typedef ssize_t (*QCryptoBlockReadFunc)(QCryptoBlock *block, + size_t offset, + uint8_t *buf, + size_t buflen, + Error **errp, + void *opaque); + +typedef ssize_t (*QCryptoBlockInitFunc)(QCryptoBlock *block, + size_t headerlen, + Error **errp, + void *opaque); + +typedef ssize_t (*QCryptoBlockWriteFunc)(QCryptoBlock *block, + size_t offset, + const uint8_t *buf, + size_t buflen, + Error **errp, + void *opaque); + +/** + * qcrypto_block_has_format: + * @format: the encryption format + * @buf: the data from head of the volume + * @len: the length of @buf in bytes + * + * Given @len bytes of data from the head of a storage volume + * in @buf, probe to determine if the volume has the encryption + * format specified in @format. + * + * Returns: true if the data in @buf matches @format + */ +bool qcrypto_block_has_format(QCryptoBlockFormat format, + const uint8_t *buf, + size_t buflen); + +typedef enum { + QCRYPTO_BLOCK_OPEN_NO_IO = (1 << 0), +} QCryptoBlockOpenFlags; + +/** + * qcrypto_block_open: + * @options: the encryption options + * @readfunc: callback for reading data from the volume + * @opaque: data to pass to @readfunc + * @flags: bitmask of QCryptoBlockOpenFlags values + * @errp: pointer to a NULL-initialized error object + * + * Create a new block encryption object for an existing + * storage volume encrypted with format identified by + * the parameters in @options. + * + * This will use @readfunc to initialize the encryption + * context based on the volume header(s), extracting the + * master key(s) as required. + * + * If @flags contains QCRYPTO_BLOCK_OPEN_NO_IO then + * the open process will be optimized to skip any parts + * that are only required to perform I/O. In particular + * this would usually avoid the need to decrypt any + * master keys. The only thing that can be done with + * the resulting QCryptoBlock object would be to query + * metadata such as the payload offset. There will be + * no cipher or ivgen objects available. + * + * If any part of initializing the encryption context + * fails an error will be returned. This could be due + * to the volume being in the wrong format, a cipher + * or IV generator algorithm that is not supported, + * or incorrect passphrases. + * + * Returns: a block encryption format, or NULL on error + */ +QCryptoBlock *qcrypto_block_open(QCryptoBlockOpenOptions *options, + QCryptoBlockReadFunc readfunc, + void *opaque, + unsigned int flags, + Error **errp); + +/** + * qcrypto_block_create: + * @format: the encryption format + * @initfunc: callback for initializing volume header + * @writefunc: callback for writing data to the volume header + * @opaque: data to pass to @initfunc and @writefunc + * @errp: pointer to a NULL-initialized error object + * + * Create a new block encryption object for initializing + * a storage volume to be encrypted with format identified + * by the parameters in @options. + * + * This method will allocate space for a new volume header + * using @initfunc and then write header data using @writefunc, + * generating new master keys, etc as required. Any existing + * data present on the volume will be irrevocably destroyed. + * + * If any part of initializing the encryption context + * fails an error will be returned. This could be due + * to the volume being in the wrong format, a cipher + * or IV generator algorithm that is not supported, + * or incorrect passphrases. + * + * Returns: a block encryption format, or NULL on error + */ +QCryptoBlock *qcrypto_block_create(QCryptoBlockCreateOptions *options, + QCryptoBlockInitFunc initfunc, + QCryptoBlockWriteFunc writefunc, + void *opaque, + Error **errp); + +/** + * @qcrypto_block_decrypt: + * @block: the block encryption object + * @startsector: the sector from which @buf was read + * @buf: the buffer to decrypt + * @len: the length of @buf in bytes + * @errp: pointer to a NULL-initialized error object + * + * Decrypt @len bytes of cipher text in @buf, writing + * plain text back into @buf + * + * Returns 0 on success, -1 on failure + */ +int qcrypto_block_decrypt(QCryptoBlock *block, + uint64_t startsector, + uint8_t *buf, + size_t len, + Error **errp); + +/** + * @qcrypto_block_encrypt: + * @block: the block encryption object + * @startsector: the sector to which @buf will be written + * @buf: the buffer to decrypt + * @len: the length of @buf in bytes + * @errp: pointer to a NULL-initialized error object + * + * Encrypt @len bytes of plain text in @buf, writing + * cipher text back into @buf + * + * Returns 0 on success, -1 on failure + */ +int qcrypto_block_encrypt(QCryptoBlock *block, + uint64_t startsector, + uint8_t *buf, + size_t len, + Error **errp); + +/** + * qcrypto_block_get_cipher: + * @block: the block encryption object + * + * Get the cipher to use for payload encryption + * + * Returns: the cipher object + */ +QCryptoCipher *qcrypto_block_get_cipher(QCryptoBlock *block); + +/** + * qcrypto_block_get_ivgen: + * @block: the block encryption object + * + * Get the initialization vector generator to use for + * payload encryption + * + * Returns: the IV generator object + */ +QCryptoIVGen *qcrypto_block_get_ivgen(QCryptoBlock *block); + + +/** + * qcrypto_block_get_kdf_hash: + * @block: the block encryption object + * + * Get the hash algorithm used with the key derivation + * function + * + * Returns: the hash algorithm + */ +QCryptoHashAlgorithm qcrypto_block_get_kdf_hash(QCryptoBlock *block); + +/** + * qcrypto_block_get_payload_offset: + * @block: the block encryption object + * + * Get the offset to the payload indicated by the + * encryption header, in bytes. + * + * Returns: the payload offset in bytes + */ +uint64_t qcrypto_block_get_payload_offset(QCryptoBlock *block); + +/** + * qcrypto_block_free: + * @block: the block encryption object + * + * Release all resources associated with the encryption + * object + */ +void qcrypto_block_free(QCryptoBlock *block); + +#endif /* QCRYPTO_BLOCK_H__ */ diff --git a/include/crypto/ivgen.h b/include/crypto/ivgen.h new file mode 100644 index 0000000000..09cdb6fcd9 --- /dev/null +++ b/include/crypto/ivgen.h @@ -0,0 +1,206 @@ +/* + * QEMU Crypto block IV generator + * + * 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/>. + * + */ + +#ifndef QCRYPTO_IVGEN_H__ +#define QCRYPTO_IVGEN_H__ + +#include "crypto/cipher.h" +#include "crypto/hash.h" + +/** + * This module provides a framework for generating initialization + * vectors for block encryption schemes using chained cipher modes + * CBC. The principle is that each disk sector is assigned a unique + * initialization vector for use for encryption of data in that + * sector. + * + * <example> + * <title>Encrypting block data with initialiation vectors</title> + * <programlisting> + * uint8_t *data = ....data to encrypt... + * size_t ndata = XXX; + * uint8_t *key = ....some encryption key... + * size_t nkey = XXX; + * uint8_t *iv; + * size_t niv; + * size_t sector = 0; + * + * g_assert((ndata % 512) == 0); + * + * QCryptoIVGen *ivgen = qcrypto_ivgen_new(QCRYPTO_IVGEN_ALG_ESSIV, + * QCRYPTO_CIPHER_ALG_AES_128, + * QCRYPTO_HASH_ALG_SHA256, + * key, nkey, errp); + * if (!ivgen) { + * return -1; + * } + * + * QCryptoCipher *cipher = qcrypto_cipher_new(QCRYPTO_CIPHER_ALG_AES_128, + * QCRYPTO_CIPHER_MODE_CBC, + * key, nkey, errp); + * if (!cipher) { + * goto error; + * } + * + * niv = qcrypto_cipher_get_iv_len(QCRYPTO_CIPHER_ALG_AES_128, + * QCRYPTO_CIPHER_MODE_CBC); + * iv = g_new0(uint8_t, niv); + * + * + * while (ndata) { + * if (qcrypto_ivgen_calculate(ivgen, sector, iv, niv, errp) < 0) { + * goto error; + * } + * if (qcrypto_cipher_setiv(cipher, iv, niv, errp) < 0) { + * goto error; + * } + * if (qcrypto_cipher_encrypt(cipher, + * data + (sector * 512), + * data + (sector * 512), + * 512, errp) < 0) { + * goto error; + * } + * sector++; + * ndata -= 512; + * } + * + * g_free(iv); + * qcrypto_ivgen_free(ivgen); + * qcrypto_cipher_free(cipher); + * return 0; + * + *error: + * g_free(iv); + * qcrypto_ivgen_free(ivgen); + * qcrypto_cipher_free(cipher); + * return -1; + * </programlisting> + * </example> + */ + +typedef struct QCryptoIVGen QCryptoIVGen; + +/* See also QCryptoIVGenAlgorithm enum in qapi/crypto.json */ + + +/** + * qcrypto_ivgen_new: + * @alg: the initialization vector generation algorithm + * @cipheralg: the cipher algorithm or 0 + * @hash: the hash algorithm or 0 + * @key: the encryption key or NULL + * @nkey: the size of @key in bytes + * + * Create a new initialization vector generator that uses + * the algorithm @alg. Whether the remaining parameters + * are required or not depends on the choice of @alg + * requested. + * + * - QCRYPTO_IVGEN_ALG_PLAIN + * + * The IVs are generated by the 32-bit truncated sector + * number. This should never be used for block devices + * that are larger than 2^32 sectors in size. + * All the other parameters are unused. + * + * - QCRYPTO_IVGEN_ALG_PLAIN64 + * + * The IVs are generated by the 64-bit sector number. + * All the other parameters are unused. + * + * - QCRYPTO_IVGEN_ALG_ESSIV: + * + * The IVs are generated by encrypting the 64-bit sector + * number with a hash of an encryption key. The @cipheralg, + * @hash, @key and @nkey parameters are all required. + * + * Returns: a new IV generator, or NULL on error + */ +QCryptoIVGen *qcrypto_ivgen_new(QCryptoIVGenAlgorithm alg, + QCryptoCipherAlgorithm cipheralg, + QCryptoHashAlgorithm hash, + const uint8_t *key, size_t nkey, + Error **errp); + +/** + * qcrypto_ivgen_calculate: + * @ivgen: the IV generator object + * @sector: the 64-bit sector number + * @iv: a pre-allocated buffer to hold the generated IV + * @niv: the number of bytes in @iv + * @errp: pointer to a NULL-initialized error object + * + * Calculate a new initialiation vector for the data + * to be stored in sector @sector. The IV will be + * written into the buffer @iv of size @niv. + * + * Returns: 0 on success, -1 on error + */ +int qcrypto_ivgen_calculate(QCryptoIVGen *ivgen, + uint64_t sector, + uint8_t *iv, size_t niv, + Error **errp); + + +/** + * qcrypto_ivgen_get_algorithm: + * @ivgen: the IV generator object + * + * Get the algorithm used by this IV generator + * + * Returns: the IV generator algorithm + */ +QCryptoIVGenAlgorithm qcrypto_ivgen_get_algorithm(QCryptoIVGen *ivgen); + + +/** + * qcrypto_ivgen_get_cipher: + * @ivgen: the IV generator object + * + * Get the cipher algorithm used by this IV generator (if + * applicable) + * + * Returns: the cipher algorithm + */ +QCryptoCipherAlgorithm qcrypto_ivgen_get_cipher(QCryptoIVGen *ivgen); + + +/** + * qcrypto_ivgen_get_hash: + * @ivgen: the IV generator object + * + * Get the hash algorithm used by this IV generator (if + * applicable) + * + * Returns: the hash algorithm + */ +QCryptoHashAlgorithm qcrypto_ivgen_get_hash(QCryptoIVGen *ivgen); + + +/** + * qcrypto_ivgen_free: + * @ivgen: the IV generator object + * + * Release all resources associated with @ivgen, or a no-op + * if @ivgen is NULL + */ +void qcrypto_ivgen_free(QCryptoIVGen *ivgen); + +#endif /* QCRYPTO_IVGEN_H__ */ diff --git a/include/crypto/pbkdf.h b/include/crypto/pbkdf.h new file mode 100644 index 0000000000..58a1fe62a1 --- /dev/null +++ b/include/crypto/pbkdf.h @@ -0,0 +1,152 @@ +/* + * QEMU Crypto PBKDF support (Password-Based Key Derivation Function) + * + * 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/>. + * + */ + +#ifndef QCRYPTO_PBKDF_H__ +#define QCRYPTO_PBKDF_H__ + +#include "crypto/hash.h" + +/** + * This module provides an interface to the PBKDF2 algorithm + * + * https://en.wikipedia.org/wiki/PBKDF2 + * + * <example> + * <title>Generating an AES encryption key from a user password</title> + * <programlisting> + * #include "crypto/cipher.h" + * #include "crypto/random.h" + * #include "crypto/pbkdf.h" + * + * .... + * + * char *password = "a-typical-awful-user-password"; + * size_t nkey = qcrypto_cipher_get_key_len(QCRYPTO_CIPHER_ALG_AES_128); + * uint8_t *salt = g_new0(uint8_t, nkey); + * uint8_t *key = g_new0(uint8_t, nkey); + * int iterations; + * QCryptoCipher *cipher; + * + * if (qcrypto_random_bytes(salt, nkey, errp) < 0) { + * g_free(key); + * g_free(salt); + * return -1; + * } + * + * iterations = qcrypto_pbkdf2_count_iters(QCRYPTO_HASH_ALG_SHA256, + * (const uint8_t *)password, + * strlen(password), + * salt, nkey, errp); + * if (iterations < 0) { + * g_free(key); + * g_free(salt); + * return -1; + * } + * + * if (qcrypto_pbkdf2(QCRYPTO_HASH_ALG_SHA256, + * (const uint8_t *)password, strlen(password), + * salt, nkey, iterations, key, nkey, errp) < 0) { + * g_free(key); + * g_free(salt); + * return -1; + * } + * + * g_free(salt); + * + * cipher = qcrypto_cipher_new(QCRYPTO_CIPHER_ALG_AES_128, + * QCRYPTO_CIPHER_MODE_ECB, + * key, nkey, errp); + * g_free(key); + * + * ....encrypt some data... + * + * qcrypto_cipher_free(cipher); + * </programlisting> + * </example> + * + */ + +/** + * qcrypto_pbkdf2_supports: + * @hash: the hash algorithm + * + * Determine if the current build supports the PBKDF2 algorithm + * in combination with the hash @hash. + * + * Returns true if supported, false otherwise + */ +bool qcrypto_pbkdf2_supports(QCryptoHashAlgorithm hash); + + +/** + * qcrypto_pbkdf2: + * @hash: the hash algorithm to use + * @key: the user password / key + * @nkey: the length of @key in bytes + * @salt: a random salt + * @nsalt: length of @salt in bytes + * @iterations: the number of iterations to compute + * @out: pointer to pre-allocated buffer to hold output + * @nout: length of @out in bytes + * @errp: pointer to a NULL-initialized error object + * + * Apply the PBKDF2 algorithm to derive an encryption + * key from a user password provided in @key. The + * @salt parameter is used to perturb the algorithm. + * The @iterations count determines how many times + * the hashing process is run, which influences how + * hard it is to crack the key. The number of @iterations + * should be large enough such that the algorithm takes + * 1 second or longer to derive a key. The derived key + * will be stored in the preallocated buffer @out. + * + * Returns: 0 on success, -1 on error + */ +int qcrypto_pbkdf2(QCryptoHashAlgorithm hash, + const uint8_t *key, size_t nkey, + const uint8_t *salt, size_t nsalt, + unsigned int iterations, + uint8_t *out, size_t nout, + Error **errp); + +/** + * qcrypto_pbkdf2_count_iters: + * @hash: the hash algorithm to use + * @key: the user password / key + * @nkey: the length of @key in bytes + * @salt: a random salt + * @nsalt: length of @salt in bytes + * @errp: pointer to a NULL-initialized error object + * + * Time the PBKDF2 algorithm to determine how many + * iterations are required to derive an encryption + * key from a user password provided in @key in 1 + * second of compute time. The result of this can + * be used as a the @iterations parameter of a later + * call to qcrypto_pbkdf2(). + * + * Returns: number of iterations in 1 second, -1 on error + */ +int qcrypto_pbkdf2_count_iters(QCryptoHashAlgorithm hash, + const uint8_t *key, size_t nkey, + const uint8_t *salt, size_t nsalt, + Error **errp); + +#endif /* QCRYPTO_PBKDF_H__ */ diff --git a/include/crypto/random.h b/include/crypto/random.h new file mode 100644 index 0000000000..b3021c4ce6 --- /dev/null +++ b/include/crypto/random.h @@ -0,0 +1,44 @@ +/* + * QEMU Crypto random number provider + * + * 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/>. + * + */ + +#ifndef QCRYPTO_RANDOM_H__ +#define QCRYPTO_RANDOM_H__ + +#include "qemu-common.h" +#include "qapi/error.h" + + +/** + * qcrypto_random_bytes: + * @buf: the buffer to fill + * @buflen: length of @buf in bytes + * @errp: pointer to a NULL-initialized error object + * + * Fill @buf with @buflen bytes of cryptographically strong + * random data + * + * Returns 0 on sucess, -1 on error + */ +int qcrypto_random_bytes(uint8_t *buf, + size_t buflen, + Error **errp); + + +#endif /* QCRYPTO_RANDOM_H__ */ diff --git a/include/crypto/xts.h b/include/crypto/xts.h new file mode 100644 index 0000000000..c2924d8ba0 --- /dev/null +++ b/include/crypto/xts.h @@ -0,0 +1,86 @@ +/* + * QEMU Crypto XTS cipher mode + * + * 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/>. + * + * This code is originally derived from public domain / WTFPL code in + * LibTomCrypt crytographic library http://libtom.org. The XTS code + * was donated by Elliptic Semiconductor Inc (www.ellipticsemi.com) + * to the LibTom Projects + * + */ + + +#ifndef QCRYPTO_XTS_H_ +#define QCRYPTO_XTS_H_ + +#include "qemu-common.h" +#include "qapi/error.h" + + +#define XTS_BLOCK_SIZE 16 + +typedef void xts_cipher_func(const void *ctx, + size_t length, + uint8_t *dst, + const uint8_t *src); + +/** + * xts_decrypt: + * @datactx: the cipher context for data decryption + * @tweakctx: the cipher context for tweak decryption + * @encfunc: the cipher function for encryption + * @decfunc: the cipher function for decryption + * @iv: the initialization vector tweak of XTS_BLOCK_SIZE bytes + * @length: the length of @dst and @src + * @dst: buffer to hold the decrypted plaintext + * @src: buffer providing the ciphertext + * + * Decrypts @src into @dst + */ +void xts_decrypt(const void *datactx, + const void *tweakctx, + xts_cipher_func *encfunc, + xts_cipher_func *decfunc, + uint8_t *iv, + size_t length, + uint8_t *dst, + const uint8_t *src); + +/** + * xts_decrypt: + * @datactx: the cipher context for data encryption + * @tweakctx: the cipher context for tweak encryption + * @encfunc: the cipher function for encryption + * @decfunc: the cipher function for decryption + * @iv: the initialization vector tweak of XTS_BLOCK_SIZE bytes + * @length: the length of @dst and @src + * @dst: buffer to hold the encrypted ciphertext + * @src: buffer providing the plaintext + * + * Decrypts @src into @dst + */ +void xts_encrypt(const void *datactx, + const void *tweakctx, + xts_cipher_func *encfunc, + xts_cipher_func *decfunc, + uint8_t *iv, + size_t length, + uint8_t *dst, + const uint8_t *src); + + +#endif /* QCRYPTO_XTS_H_ */ |