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Also remove preprocessor logic for MBEDTLS_CONFIG_FILE, since build_info.h alreadyy handles it. This commit was generated using the following script: # ======================== #!/bin/sh git ls-files | grep -v '^include/mbedtls/build_info\.h$' | xargs sed -b -E -i ' /^#if !?defined\(MBEDTLS_CONFIG_FILE\)/i#include "mbedtls/build_info.h" //,/^#endif/d ' # ======================== Signed-off-by: Bence Szépkúti <bence.szepkuti@arm.com>
627 lines
27 KiB
C
627 lines
27 KiB
C
/**
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* \file aes.h
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*
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* \brief This file contains AES definitions and functions.
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*
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* The Advanced Encryption Standard (AES) specifies a FIPS-approved
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* cryptographic algorithm that can be used to protect electronic
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* data.
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*
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* The AES algorithm is a symmetric block cipher that can
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* encrypt and decrypt information. For more information, see
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* <em>FIPS Publication 197: Advanced Encryption Standard</em> and
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* <em>ISO/IEC 18033-2:2006: Information technology -- Security
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* techniques -- Encryption algorithms -- Part 2: Asymmetric
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* ciphers</em>.
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*
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* The AES-XTS block mode is standardized by NIST SP 800-38E
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* <https://nvlpubs.nist.gov/nistpubs/legacy/sp/nistspecialpublication800-38e.pdf>
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* and described in detail by IEEE P1619
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* <https://ieeexplore.ieee.org/servlet/opac?punumber=4375278>.
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*/
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/*
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* Copyright The Mbed TLS Contributors
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* SPDX-License-Identifier: Apache-2.0
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*
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* Licensed under the Apache License, Version 2.0 (the "License"); you may
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* not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
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* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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#ifndef MBEDTLS_AES_H
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#define MBEDTLS_AES_H
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#include "mbedtls/private_access.h"
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#include "mbedtls/build_info.h"
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#include <stddef.h>
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#include <stdint.h>
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/* padlock.c and aesni.c rely on these values! */
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#define MBEDTLS_AES_ENCRYPT 1 /**< AES encryption. */
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#define MBEDTLS_AES_DECRYPT 0 /**< AES decryption. */
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/* Error codes in range 0x0020-0x0022 */
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#define MBEDTLS_ERR_AES_INVALID_KEY_LENGTH -0x0020 /**< Invalid key length. */
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#define MBEDTLS_ERR_AES_INVALID_INPUT_LENGTH -0x0022 /**< Invalid data input length. */
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/* Error codes in range 0x0021-0x0025 */
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#define MBEDTLS_ERR_AES_BAD_INPUT_DATA -0x0021 /**< Invalid input data. */
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#if ( defined(__ARMCC_VERSION) || defined(_MSC_VER) ) && \
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!defined(inline) && !defined(__cplusplus)
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#define inline __inline
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#endif
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#ifdef __cplusplus
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extern "C" {
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#endif
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#if !defined(MBEDTLS_AES_ALT)
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// Regular implementation
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//
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/**
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* \brief The AES context-type definition.
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*/
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typedef struct mbedtls_aes_context
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{
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int MBEDTLS_PRIVATE(nr); /*!< The number of rounds. */
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uint32_t *MBEDTLS_PRIVATE(rk); /*!< AES round keys. */
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uint32_t MBEDTLS_PRIVATE(buf)[68]; /*!< Unaligned data buffer. This buffer can
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hold 32 extra Bytes, which can be used for
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one of the following purposes:
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<ul><li>Alignment if VIA padlock is
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used.</li>
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<li>Simplifying key expansion in the 256-bit
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case by generating an extra round key.
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</li></ul> */
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}
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mbedtls_aes_context;
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#if defined(MBEDTLS_CIPHER_MODE_XTS)
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/**
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* \brief The AES XTS context-type definition.
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*/
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typedef struct mbedtls_aes_xts_context
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{
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mbedtls_aes_context MBEDTLS_PRIVATE(crypt); /*!< The AES context to use for AES block
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encryption or decryption. */
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mbedtls_aes_context MBEDTLS_PRIVATE(tweak); /*!< The AES context used for tweak
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computation. */
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} mbedtls_aes_xts_context;
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#endif /* MBEDTLS_CIPHER_MODE_XTS */
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#else /* MBEDTLS_AES_ALT */
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#include "aes_alt.h"
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#endif /* MBEDTLS_AES_ALT */
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/**
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* \brief This function initializes the specified AES context.
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*
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* It must be the first API called before using
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* the context.
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*
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* \param ctx The AES context to initialize. This must not be \c NULL.
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*/
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void mbedtls_aes_init( mbedtls_aes_context *ctx );
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/**
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* \brief This function releases and clears the specified AES context.
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*
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* \param ctx The AES context to clear.
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* If this is \c NULL, this function does nothing.
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* Otherwise, the context must have been at least initialized.
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*/
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void mbedtls_aes_free( mbedtls_aes_context *ctx );
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#if defined(MBEDTLS_CIPHER_MODE_XTS)
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/**
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* \brief This function initializes the specified AES XTS context.
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*
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* It must be the first API called before using
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* the context.
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*
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* \param ctx The AES XTS context to initialize. This must not be \c NULL.
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*/
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void mbedtls_aes_xts_init( mbedtls_aes_xts_context *ctx );
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/**
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* \brief This function releases and clears the specified AES XTS context.
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*
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* \param ctx The AES XTS context to clear.
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* If this is \c NULL, this function does nothing.
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* Otherwise, the context must have been at least initialized.
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*/
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void mbedtls_aes_xts_free( mbedtls_aes_xts_context *ctx );
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#endif /* MBEDTLS_CIPHER_MODE_XTS */
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/**
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* \brief This function sets the encryption key.
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*
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* \param ctx The AES context to which the key should be bound.
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* It must be initialized.
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* \param key The encryption key.
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* This must be a readable buffer of size \p keybits bits.
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* \param keybits The size of data passed in bits. Valid options are:
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* <ul><li>128 bits</li>
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* <li>192 bits</li>
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* <li>256 bits</li></ul>
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*
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* \return \c 0 on success.
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* \return #MBEDTLS_ERR_AES_INVALID_KEY_LENGTH on failure.
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*/
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int mbedtls_aes_setkey_enc( mbedtls_aes_context *ctx, const unsigned char *key,
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unsigned int keybits );
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/**
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* \brief This function sets the decryption key.
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*
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* \param ctx The AES context to which the key should be bound.
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* It must be initialized.
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* \param key The decryption key.
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* This must be a readable buffer of size \p keybits bits.
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* \param keybits The size of data passed. Valid options are:
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* <ul><li>128 bits</li>
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* <li>192 bits</li>
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* <li>256 bits</li></ul>
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*
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* \return \c 0 on success.
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* \return #MBEDTLS_ERR_AES_INVALID_KEY_LENGTH on failure.
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*/
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int mbedtls_aes_setkey_dec( mbedtls_aes_context *ctx, const unsigned char *key,
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unsigned int keybits );
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#if defined(MBEDTLS_CIPHER_MODE_XTS)
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/**
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* \brief This function prepares an XTS context for encryption and
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* sets the encryption key.
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*
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* \param ctx The AES XTS context to which the key should be bound.
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* It must be initialized.
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* \param key The encryption key. This is comprised of the XTS key1
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* concatenated with the XTS key2.
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* This must be a readable buffer of size \p keybits bits.
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* \param keybits The size of \p key passed in bits. Valid options are:
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* <ul><li>256 bits (each of key1 and key2 is a 128-bit key)</li>
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* <li>512 bits (each of key1 and key2 is a 256-bit key)</li></ul>
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*
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* \return \c 0 on success.
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* \return #MBEDTLS_ERR_AES_INVALID_KEY_LENGTH on failure.
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*/
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int mbedtls_aes_xts_setkey_enc( mbedtls_aes_xts_context *ctx,
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const unsigned char *key,
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unsigned int keybits );
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/**
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* \brief This function prepares an XTS context for decryption and
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* sets the decryption key.
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*
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* \param ctx The AES XTS context to which the key should be bound.
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* It must be initialized.
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* \param key The decryption key. This is comprised of the XTS key1
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* concatenated with the XTS key2.
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* This must be a readable buffer of size \p keybits bits.
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* \param keybits The size of \p key passed in bits. Valid options are:
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* <ul><li>256 bits (each of key1 and key2 is a 128-bit key)</li>
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* <li>512 bits (each of key1 and key2 is a 256-bit key)</li></ul>
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*
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* \return \c 0 on success.
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* \return #MBEDTLS_ERR_AES_INVALID_KEY_LENGTH on failure.
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*/
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int mbedtls_aes_xts_setkey_dec( mbedtls_aes_xts_context *ctx,
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const unsigned char *key,
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unsigned int keybits );
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#endif /* MBEDTLS_CIPHER_MODE_XTS */
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/**
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* \brief This function performs an AES single-block encryption or
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* decryption operation.
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*
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* It performs the operation defined in the \p mode parameter
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* (encrypt or decrypt), on the input data buffer defined in
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* the \p input parameter.
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*
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* mbedtls_aes_init(), and either mbedtls_aes_setkey_enc() or
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* mbedtls_aes_setkey_dec() must be called before the first
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* call to this API with the same context.
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*
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* \param ctx The AES context to use for encryption or decryption.
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* It must be initialized and bound to a key.
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* \param mode The AES operation: #MBEDTLS_AES_ENCRYPT or
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* #MBEDTLS_AES_DECRYPT.
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* \param input The buffer holding the input data.
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* It must be readable and at least \c 16 Bytes long.
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* \param output The buffer where the output data will be written.
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* It must be writeable and at least \c 16 Bytes long.
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* \return \c 0 on success.
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*/
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int mbedtls_aes_crypt_ecb( mbedtls_aes_context *ctx,
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int mode,
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const unsigned char input[16],
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unsigned char output[16] );
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#if defined(MBEDTLS_CIPHER_MODE_CBC)
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/**
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* \brief This function performs an AES-CBC encryption or decryption operation
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* on full blocks.
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*
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* It performs the operation defined in the \p mode
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* parameter (encrypt/decrypt), on the input data buffer defined in
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* the \p input parameter.
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*
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* It can be called as many times as needed, until all the input
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* data is processed. mbedtls_aes_init(), and either
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* mbedtls_aes_setkey_enc() or mbedtls_aes_setkey_dec() must be called
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* before the first call to this API with the same context.
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*
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* \note This function operates on full blocks, that is, the input size
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* must be a multiple of the AES block size of \c 16 Bytes.
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*
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* \note Upon exit, the content of the IV is updated so that you can
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* call the same function again on the next
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* block(s) of data and get the same result as if it was
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* encrypted in one call. This allows a "streaming" usage.
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* If you need to retain the contents of the IV, you should
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* either save it manually or use the cipher module instead.
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*
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*
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* \param ctx The AES context to use for encryption or decryption.
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* It must be initialized and bound to a key.
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* \param mode The AES operation: #MBEDTLS_AES_ENCRYPT or
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* #MBEDTLS_AES_DECRYPT.
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* \param length The length of the input data in Bytes. This must be a
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* multiple of the block size (\c 16 Bytes).
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* \param iv Initialization vector (updated after use).
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* It must be a readable and writeable buffer of \c 16 Bytes.
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* \param input The buffer holding the input data.
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* It must be readable and of size \p length Bytes.
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* \param output The buffer holding the output data.
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* It must be writeable and of size \p length Bytes.
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*
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* \return \c 0 on success.
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* \return #MBEDTLS_ERR_AES_INVALID_INPUT_LENGTH
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* on failure.
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*/
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int mbedtls_aes_crypt_cbc( mbedtls_aes_context *ctx,
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int mode,
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size_t length,
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unsigned char iv[16],
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const unsigned char *input,
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unsigned char *output );
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#endif /* MBEDTLS_CIPHER_MODE_CBC */
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#if defined(MBEDTLS_CIPHER_MODE_XTS)
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/**
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* \brief This function performs an AES-XTS encryption or decryption
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* operation for an entire XTS data unit.
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*
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* AES-XTS encrypts or decrypts blocks based on their location as
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* defined by a data unit number. The data unit number must be
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* provided by \p data_unit.
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*
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* NIST SP 800-38E limits the maximum size of a data unit to 2^20
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* AES blocks. If the data unit is larger than this, this function
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* returns #MBEDTLS_ERR_AES_INVALID_INPUT_LENGTH.
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*
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* \param ctx The AES XTS context to use for AES XTS operations.
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* It must be initialized and bound to a key.
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* \param mode The AES operation: #MBEDTLS_AES_ENCRYPT or
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* #MBEDTLS_AES_DECRYPT.
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* \param length The length of a data unit in Bytes. This can be any
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* length between 16 bytes and 2^24 bytes inclusive
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* (between 1 and 2^20 block cipher blocks).
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* \param data_unit The address of the data unit encoded as an array of 16
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* bytes in little-endian format. For disk encryption, this
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* is typically the index of the block device sector that
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* contains the data.
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* \param input The buffer holding the input data (which is an entire
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* data unit). This function reads \p length Bytes from \p
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* input.
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* \param output The buffer holding the output data (which is an entire
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* data unit). This function writes \p length Bytes to \p
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* output.
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*
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* \return \c 0 on success.
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* \return #MBEDTLS_ERR_AES_INVALID_INPUT_LENGTH if \p length is
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* smaller than an AES block in size (16 Bytes) or if \p
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* length is larger than 2^20 blocks (16 MiB).
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*/
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int mbedtls_aes_crypt_xts( mbedtls_aes_xts_context *ctx,
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int mode,
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size_t length,
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const unsigned char data_unit[16],
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const unsigned char *input,
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unsigned char *output );
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#endif /* MBEDTLS_CIPHER_MODE_XTS */
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#if defined(MBEDTLS_CIPHER_MODE_CFB)
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/**
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* \brief This function performs an AES-CFB128 encryption or decryption
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* operation.
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*
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* It performs the operation defined in the \p mode
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* parameter (encrypt or decrypt), on the input data buffer
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* defined in the \p input parameter.
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*
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* For CFB, you must set up the context with mbedtls_aes_setkey_enc(),
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* regardless of whether you are performing an encryption or decryption
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* operation, that is, regardless of the \p mode parameter. This is
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* because CFB mode uses the same key schedule for encryption and
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* decryption.
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*
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* \note Upon exit, the content of the IV is updated so that you can
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* call the same function again on the next
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* block(s) of data and get the same result as if it was
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* encrypted in one call. This allows a "streaming" usage.
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* If you need to retain the contents of the
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* IV, you must either save it manually or use the cipher
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* module instead.
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*
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*
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* \param ctx The AES context to use for encryption or decryption.
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* It must be initialized and bound to a key.
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* \param mode The AES operation: #MBEDTLS_AES_ENCRYPT or
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* #MBEDTLS_AES_DECRYPT.
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* \param length The length of the input data in Bytes.
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* \param iv_off The offset in IV (updated after use).
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* It must point to a valid \c size_t.
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* \param iv The initialization vector (updated after use).
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* It must be a readable and writeable buffer of \c 16 Bytes.
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* \param input The buffer holding the input data.
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* It must be readable and of size \p length Bytes.
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* \param output The buffer holding the output data.
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* It must be writeable and of size \p length Bytes.
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*
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* \return \c 0 on success.
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*/
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int mbedtls_aes_crypt_cfb128( mbedtls_aes_context *ctx,
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int mode,
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size_t length,
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size_t *iv_off,
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unsigned char iv[16],
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const unsigned char *input,
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unsigned char *output );
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/**
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* \brief This function performs an AES-CFB8 encryption or decryption
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* operation.
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*
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* It performs the operation defined in the \p mode
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* parameter (encrypt/decrypt), on the input data buffer defined
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* in the \p input parameter.
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*
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* Due to the nature of CFB, you must use the same key schedule for
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* both encryption and decryption operations. Therefore, you must
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* use the context initialized with mbedtls_aes_setkey_enc() for
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* both #MBEDTLS_AES_ENCRYPT and #MBEDTLS_AES_DECRYPT.
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*
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* \note Upon exit, the content of the IV is updated so that you can
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* call the same function again on the next
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* block(s) of data and get the same result as if it was
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* encrypted in one call. This allows a "streaming" usage.
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* If you need to retain the contents of the
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* IV, you should either save it manually or use the cipher
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* module instead.
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*
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*
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* \param ctx The AES context to use for encryption or decryption.
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* It must be initialized and bound to a key.
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* \param mode The AES operation: #MBEDTLS_AES_ENCRYPT or
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* #MBEDTLS_AES_DECRYPT
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* \param length The length of the input data.
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* \param iv The initialization vector (updated after use).
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* It must be a readable and writeable buffer of \c 16 Bytes.
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* \param input The buffer holding the input data.
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* It must be readable and of size \p length Bytes.
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* \param output The buffer holding the output data.
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* It must be writeable and of size \p length Bytes.
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*
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* \return \c 0 on success.
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*/
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int mbedtls_aes_crypt_cfb8( mbedtls_aes_context *ctx,
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int mode,
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size_t length,
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unsigned char iv[16],
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const unsigned char *input,
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unsigned char *output );
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#endif /*MBEDTLS_CIPHER_MODE_CFB */
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#if defined(MBEDTLS_CIPHER_MODE_OFB)
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/**
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* \brief This function performs an AES-OFB (Output Feedback Mode)
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* encryption or decryption operation.
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*
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* For OFB, you must set up the context with
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* mbedtls_aes_setkey_enc(), regardless of whether you are
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* performing an encryption or decryption operation. This is
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* because OFB mode uses the same key schedule for encryption and
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* decryption.
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*
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* The OFB operation is identical for encryption or decryption,
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* therefore no operation mode needs to be specified.
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|
*
|
|
* \note Upon exit, the content of iv, the Initialisation Vector, is
|
|
* updated so that you can call the same function again on the next
|
|
* block(s) of data and get the same result as if it was encrypted
|
|
* in one call. This allows a "streaming" usage, by initialising
|
|
* iv_off to 0 before the first call, and preserving its value
|
|
* between calls.
|
|
*
|
|
* For non-streaming use, the iv should be initialised on each call
|
|
* to a unique value, and iv_off set to 0 on each call.
|
|
*
|
|
* If you need to retain the contents of the initialisation vector,
|
|
* you must either save it manually or use the cipher module
|
|
* instead.
|
|
*
|
|
* \warning For the OFB mode, the initialisation vector must be unique
|
|
* every encryption operation. Reuse of an initialisation vector
|
|
* will compromise security.
|
|
*
|
|
* \param ctx The AES context to use for encryption or decryption.
|
|
* It must be initialized and bound to a key.
|
|
* \param length The length of the input data.
|
|
* \param iv_off The offset in IV (updated after use).
|
|
* It must point to a valid \c size_t.
|
|
* \param iv The initialization vector (updated after use).
|
|
* It must be a readable and writeable buffer of \c 16 Bytes.
|
|
* \param input The buffer holding the input data.
|
|
* It must be readable and of size \p length Bytes.
|
|
* \param output The buffer holding the output data.
|
|
* It must be writeable and of size \p length Bytes.
|
|
*
|
|
* \return \c 0 on success.
|
|
*/
|
|
int mbedtls_aes_crypt_ofb( mbedtls_aes_context *ctx,
|
|
size_t length,
|
|
size_t *iv_off,
|
|
unsigned char iv[16],
|
|
const unsigned char *input,
|
|
unsigned char *output );
|
|
|
|
#endif /* MBEDTLS_CIPHER_MODE_OFB */
|
|
|
|
#if defined(MBEDTLS_CIPHER_MODE_CTR)
|
|
/**
|
|
* \brief This function performs an AES-CTR encryption or decryption
|
|
* operation.
|
|
*
|
|
* This function performs the operation defined in the \p mode
|
|
* parameter (encrypt/decrypt), on the input data buffer
|
|
* defined in the \p input parameter.
|
|
*
|
|
* Due to the nature of CTR, you must use the same key schedule
|
|
* for both encryption and decryption operations. Therefore, you
|
|
* must use the context initialized with mbedtls_aes_setkey_enc()
|
|
* for both #MBEDTLS_AES_ENCRYPT and #MBEDTLS_AES_DECRYPT.
|
|
*
|
|
* \warning You must never reuse a nonce value with the same key. Doing so
|
|
* would void the encryption for the two messages encrypted with
|
|
* the same nonce and key.
|
|
*
|
|
* There are two common strategies for managing nonces with CTR:
|
|
*
|
|
* 1. You can handle everything as a single message processed over
|
|
* successive calls to this function. In that case, you want to
|
|
* set \p nonce_counter and \p nc_off to 0 for the first call, and
|
|
* then preserve the values of \p nonce_counter, \p nc_off and \p
|
|
* stream_block across calls to this function as they will be
|
|
* updated by this function.
|
|
*
|
|
* With this strategy, you must not encrypt more than 2**128
|
|
* blocks of data with the same key.
|
|
*
|
|
* 2. You can encrypt separate messages by dividing the \p
|
|
* nonce_counter buffer in two areas: the first one used for a
|
|
* per-message nonce, handled by yourself, and the second one
|
|
* updated by this function internally.
|
|
*
|
|
* For example, you might reserve the first 12 bytes for the
|
|
* per-message nonce, and the last 4 bytes for internal use. In that
|
|
* case, before calling this function on a new message you need to
|
|
* set the first 12 bytes of \p nonce_counter to your chosen nonce
|
|
* value, the last 4 to 0, and \p nc_off to 0 (which will cause \p
|
|
* stream_block to be ignored). That way, you can encrypt at most
|
|
* 2**96 messages of up to 2**32 blocks each with the same key.
|
|
*
|
|
* The per-message nonce (or information sufficient to reconstruct
|
|
* it) needs to be communicated with the ciphertext and must be unique.
|
|
* The recommended way to ensure uniqueness is to use a message
|
|
* counter. An alternative is to generate random nonces, but this
|
|
* limits the number of messages that can be securely encrypted:
|
|
* for example, with 96-bit random nonces, you should not encrypt
|
|
* more than 2**32 messages with the same key.
|
|
*
|
|
* Note that for both stategies, sizes are measured in blocks and
|
|
* that an AES block is 16 bytes.
|
|
*
|
|
* \warning Upon return, \p stream_block contains sensitive data. Its
|
|
* content must not be written to insecure storage and should be
|
|
* securely discarded as soon as it's no longer needed.
|
|
*
|
|
* \param ctx The AES context to use for encryption or decryption.
|
|
* It must be initialized and bound to a key.
|
|
* \param length The length of the input data.
|
|
* \param nc_off The offset in the current \p stream_block, for
|
|
* resuming within the current cipher stream. The
|
|
* offset pointer should be 0 at the start of a stream.
|
|
* It must point to a valid \c size_t.
|
|
* \param nonce_counter The 128-bit nonce and counter.
|
|
* It must be a readable-writeable buffer of \c 16 Bytes.
|
|
* \param stream_block The saved stream block for resuming. This is
|
|
* overwritten by the function.
|
|
* It must be a readable-writeable buffer of \c 16 Bytes.
|
|
* \param input The buffer holding the input data.
|
|
* It must be readable and of size \p length Bytes.
|
|
* \param output The buffer holding the output data.
|
|
* It must be writeable and of size \p length Bytes.
|
|
*
|
|
* \return \c 0 on success.
|
|
*/
|
|
int mbedtls_aes_crypt_ctr( mbedtls_aes_context *ctx,
|
|
size_t length,
|
|
size_t *nc_off,
|
|
unsigned char nonce_counter[16],
|
|
unsigned char stream_block[16],
|
|
const unsigned char *input,
|
|
unsigned char *output );
|
|
#endif /* MBEDTLS_CIPHER_MODE_CTR */
|
|
|
|
/**
|
|
* \brief Internal AES block encryption function. This is only
|
|
* exposed to allow overriding it using
|
|
* \c MBEDTLS_AES_ENCRYPT_ALT.
|
|
*
|
|
* \param ctx The AES context to use for encryption.
|
|
* \param input The plaintext block.
|
|
* \param output The output (ciphertext) block.
|
|
*
|
|
* \return \c 0 on success.
|
|
*/
|
|
int mbedtls_internal_aes_encrypt( mbedtls_aes_context *ctx,
|
|
const unsigned char input[16],
|
|
unsigned char output[16] );
|
|
|
|
/**
|
|
* \brief Internal AES block decryption function. This is only
|
|
* exposed to allow overriding it using see
|
|
* \c MBEDTLS_AES_DECRYPT_ALT.
|
|
*
|
|
* \param ctx The AES context to use for decryption.
|
|
* \param input The ciphertext block.
|
|
* \param output The output (plaintext) block.
|
|
*
|
|
* \return \c 0 on success.
|
|
*/
|
|
int mbedtls_internal_aes_decrypt( mbedtls_aes_context *ctx,
|
|
const unsigned char input[16],
|
|
unsigned char output[16] );
|
|
|
|
#if defined(MBEDTLS_SELF_TEST)
|
|
/**
|
|
* \brief Checkup routine.
|
|
*
|
|
* \return \c 0 on success.
|
|
* \return \c 1 on failure.
|
|
*/
|
|
int mbedtls_aes_self_test( int verbose );
|
|
|
|
#endif /* MBEDTLS_SELF_TEST */
|
|
|
|
#ifdef __cplusplus
|
|
}
|
|
#endif
|
|
|
|
#endif /* aes.h */
|