|  | /* | 
|  | * QEMU Crypto cipher algorithms | 
|  | * | 
|  | * Copyright (c) 2015 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 2.1 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_CIPHER_H | 
|  | #define QCRYPTO_CIPHER_H | 
|  |  | 
|  | #include "qapi/qapi-types-crypto.h" | 
|  |  | 
|  | typedef struct QCryptoCipher QCryptoCipher; | 
|  | typedef struct QCryptoCipherDriver QCryptoCipherDriver; | 
|  |  | 
|  | /* See also "QCryptoCipherAlgorithm" and "QCryptoCipherMode" | 
|  | * enums defined in qapi/crypto.json */ | 
|  |  | 
|  | /** | 
|  | * QCryptoCipher: | 
|  | * | 
|  | * The QCryptoCipher object provides a way to perform encryption | 
|  | * and decryption of data, with a standard API, regardless of the | 
|  | * algorithm used. It further isolates the calling code from the | 
|  | * details of the specific underlying implementation, whether | 
|  | * built-in, libgcrypt or nettle. | 
|  | * | 
|  | * Each QCryptoCipher object is capable of performing both | 
|  | * encryption and decryption, and can operate in a number | 
|  | * or modes including ECB, CBC. | 
|  | * | 
|  | * <example> | 
|  | *   <title>Encrypting data with AES-128 in CBC mode</title> | 
|  | *   <programlisting> | 
|  | * QCryptoCipher *cipher; | 
|  | * uint8_t key = ....; | 
|  | * size_t keylen = 16; | 
|  | * uint8_t iv = ....; | 
|  | * | 
|  | * if (!qcrypto_cipher_supports(QCRYPTO_CIPHER_ALG_AES_128)) { | 
|  | *    error_report(errp, "Feature <blah> requires AES cipher support"); | 
|  | *    return -1; | 
|  | * } | 
|  | * | 
|  | * cipher = qcrypto_cipher_new(QCRYPTO_CIPHER_ALG_AES_128, | 
|  | *                             QCRYPTO_CIPHER_MODE_CBC, | 
|  | *                             key, keylen, | 
|  | *                             errp); | 
|  | * if (!cipher) { | 
|  | *    return -1; | 
|  | * } | 
|  | * | 
|  | * if (qcrypto_cipher_set_iv(cipher, iv, keylen, errp) < 0) { | 
|  | *    return -1; | 
|  | * } | 
|  | * | 
|  | * if (qcrypto_cipher_encrypt(cipher, rawdata, encdata, datalen, errp) < 0) { | 
|  | *    return -1; | 
|  | * } | 
|  | * | 
|  | * qcrypto_cipher_free(cipher); | 
|  | *   </programlisting> | 
|  | * </example> | 
|  | * | 
|  | */ | 
|  |  | 
|  | struct QCryptoCipher { | 
|  | QCryptoCipherAlgorithm alg; | 
|  | QCryptoCipherMode mode; | 
|  | const QCryptoCipherDriver *driver; | 
|  | }; | 
|  |  | 
|  | /** | 
|  | * qcrypto_cipher_supports: | 
|  | * @alg: the cipher algorithm | 
|  | * @mode: the cipher mode | 
|  | * | 
|  | * Determine if @alg cipher algorithm in @mode is supported by the | 
|  | * current configured build | 
|  | * | 
|  | * Returns: true if the algorithm is supported, false otherwise | 
|  | */ | 
|  | bool qcrypto_cipher_supports(QCryptoCipherAlgorithm alg, | 
|  | QCryptoCipherMode mode); | 
|  |  | 
|  | /** | 
|  | * qcrypto_cipher_get_block_len: | 
|  | * @alg: the cipher algorithm | 
|  | * | 
|  | * Get the required data block size in bytes. When | 
|  | * encrypting data, it must be a multiple of the | 
|  | * block size. | 
|  | * | 
|  | * Returns: the block size in bytes | 
|  | */ | 
|  | size_t qcrypto_cipher_get_block_len(QCryptoCipherAlgorithm alg); | 
|  |  | 
|  |  | 
|  | /** | 
|  | * qcrypto_cipher_get_key_len: | 
|  | * @alg: the cipher algorithm | 
|  | * | 
|  | * Get the required key size in bytes. | 
|  | * | 
|  | * Returns: the key size in bytes | 
|  | */ | 
|  | size_t qcrypto_cipher_get_key_len(QCryptoCipherAlgorithm alg); | 
|  |  | 
|  |  | 
|  | /** | 
|  | * qcrypto_cipher_get_iv_len: | 
|  | * @alg: the cipher algorithm | 
|  | * @mode: the cipher mode | 
|  | * | 
|  | * Get the required initialization vector size | 
|  | * in bytes, if one is required. | 
|  | * | 
|  | * Returns: the IV size in bytes, or 0 if no IV is permitted | 
|  | */ | 
|  | size_t qcrypto_cipher_get_iv_len(QCryptoCipherAlgorithm alg, | 
|  | QCryptoCipherMode mode); | 
|  |  | 
|  |  | 
|  | /** | 
|  | * qcrypto_cipher_new: | 
|  | * @alg: the cipher algorithm | 
|  | * @mode: the cipher usage mode | 
|  | * @key: the private key bytes | 
|  | * @nkey: the length of @key | 
|  | * @errp: pointer to a NULL-initialized error object | 
|  | * | 
|  | * Creates a new cipher object for encrypting/decrypting | 
|  | * data with the algorithm @alg in the usage mode @mode. | 
|  | * | 
|  | * The @key parameter provides the bytes representing | 
|  | * the encryption/decryption key to use. The @nkey parameter | 
|  | * specifies the length of @key in bytes. Each algorithm has | 
|  | * one or more valid key lengths, and it is an error to provide | 
|  | * a key of the incorrect length. | 
|  | * | 
|  | * The returned cipher object must be released with | 
|  | * qcrypto_cipher_free() when no longer required | 
|  | * | 
|  | * Returns: a new cipher object, or NULL on error | 
|  | */ | 
|  | QCryptoCipher *qcrypto_cipher_new(QCryptoCipherAlgorithm alg, | 
|  | QCryptoCipherMode mode, | 
|  | const uint8_t *key, size_t nkey, | 
|  | Error **errp); | 
|  |  | 
|  | /** | 
|  | * qcrypto_cipher_free: | 
|  | * @cipher: the cipher object | 
|  | * | 
|  | * Release the memory associated with @cipher that | 
|  | * was previously allocated by qcrypto_cipher_new() | 
|  | */ | 
|  | void qcrypto_cipher_free(QCryptoCipher *cipher); | 
|  |  | 
|  | G_DEFINE_AUTOPTR_CLEANUP_FUNC(QCryptoCipher, qcrypto_cipher_free) | 
|  |  | 
|  | /** | 
|  | * qcrypto_cipher_encrypt: | 
|  | * @cipher: the cipher object | 
|  | * @in: buffer holding the plain text input data | 
|  | * @out: buffer to fill with the cipher text output data | 
|  | * @len: the length of @in and @out buffers | 
|  | * @errp: pointer to a NULL-initialized error object | 
|  | * | 
|  | * Encrypts the plain text stored in @in, filling | 
|  | * @out with the resulting ciphered text. Both the | 
|  | * @in and @out buffers must have the same size, | 
|  | * given by @len. | 
|  | * | 
|  | * Returns: 0 on success, or -1 on error | 
|  | */ | 
|  | int qcrypto_cipher_encrypt(QCryptoCipher *cipher, | 
|  | const void *in, | 
|  | void *out, | 
|  | size_t len, | 
|  | Error **errp); | 
|  |  | 
|  |  | 
|  | /** | 
|  | * qcrypto_cipher_decrypt: | 
|  | * @cipher: the cipher object | 
|  | * @in: buffer holding the cipher text input data | 
|  | * @out: buffer to fill with the plain text output data | 
|  | * @len: the length of @in and @out buffers | 
|  | * @errp: pointer to a NULL-initialized error object | 
|  | * | 
|  | * Decrypts the cipher text stored in @in, filling | 
|  | * @out with the resulting plain text. Both the | 
|  | * @in and @out buffers must have the same size, | 
|  | * given by @len. | 
|  | * | 
|  | * Returns: 0 on success, or -1 on error | 
|  | */ | 
|  | int qcrypto_cipher_decrypt(QCryptoCipher *cipher, | 
|  | const void *in, | 
|  | void *out, | 
|  | size_t len, | 
|  | Error **errp); | 
|  |  | 
|  | /** | 
|  | * qcrypto_cipher_setiv: | 
|  | * @cipher: the cipher object | 
|  | * @iv: the initialization vector or counter (CTR mode) bytes | 
|  | * @niv: the length of @iv | 
|  | * @errpr: pointer to a NULL-initialized error object | 
|  | * | 
|  | * If the @cipher object is setup to use a mode that requires | 
|  | * initialization vectors or counter, this sets the @niv | 
|  | * bytes. The @iv data should have the same length as the | 
|  | * cipher key used when originally constructing the cipher | 
|  | * object. It is an error to set an initialization vector | 
|  | * or counter if the cipher mode does not require one. | 
|  | * | 
|  | * Returns: 0 on success, -1 on error | 
|  | */ | 
|  | int qcrypto_cipher_setiv(QCryptoCipher *cipher, | 
|  | const uint8_t *iv, size_t niv, | 
|  | Error **errp); | 
|  |  | 
|  | #endif /* QCRYPTO_CIPHER_H */ |