/**
* \file block_cipher_internal.h
*
* \brief Lightweight abstraction layer for block ciphers with 128 bit blocks,
* for use by the GCM and CCM modules.
*/
/*
* Copyright The Mbed TLS Contributors
* SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
*/
#ifndef MBEDTLS_BLOCK_CIPHER_INTERNAL_H
#define MBEDTLS_BLOCK_CIPHER_INTERNAL_H
#include "mbedtls/build_info.h"
#include "mbedtls/cipher.h"
#include "mbedtls/block_cipher.h"
#ifdef __cplusplus
extern "C" {
#endif
/**
* \brief Initialize the context.
* This must be the first API call before using the context.
*
* \param ctx The context to initialize.
*/
static inline void mbedtls_block_cipher_init(mbedtls_block_cipher_context_t *ctx)
{
memset(ctx, 0, sizeof(*ctx));
}
/**
* \brief Set the block cipher to use with this context.
* This must be called after mbedtls_block_cipher_init().
*
* \param ctx The context to set up.
* \param cipher_id The identifier of the cipher to use.
* This must be either AES, ARIA or Camellia.
* Warning: this is a ::mbedtls_cipher_id_t,
* not a ::mbedtls_block_cipher_id_t!
*
* \retval \c 0 on success.
* \retval #MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA if \p cipher_id was
* invalid.
*/
int mbedtls_block_cipher_setup(mbedtls_block_cipher_context_t *ctx,
mbedtls_cipher_id_t cipher_id);
/**
* \brief Set the key into the context.
*
* \param ctx The context to configure.
* \param key The buffer holding the key material.
* \param key_bitlen The size of the key in bits.
*
* \retval \c 0 on success.
* \retval #MBEDTLS_ERR_CIPHER_INVALID_CONTEXT if the context was not
* properly set up before calling this function.
* \retval One of #MBEDTLS_ERR_AES_INVALID_KEY_LENGTH,
* #MBEDTLS_ERR_ARIA_BAD_INPUT_DATA,
* #MBEDTLS_ERR_CAMELLIA_BAD_INPUT_DATA if \p key_bitlen is
* invalid.
*/
int mbedtls_block_cipher_setkey(mbedtls_block_cipher_context_t *ctx,
const unsigned char *key,
unsigned key_bitlen);
/**
* \brief Encrypt one block (16 bytes) with the configured key.
*
* \param ctx The context holding the key.
* \param input The buffer holding the input block. Must be 16 bytes.
* \param output The buffer to which the output block will be written.
* Must be writable and 16 bytes long.
* This must either not overlap with \p input, or be equal.
*
* \retval \c 0 on success.
* \retval #MBEDTLS_ERR_CIPHER_INVALID_CONTEXT if the context was not
* properly set up before calling this function.
* \retval Another negative value if encryption failed.
*/
int mbedtls_block_cipher_encrypt(mbedtls_block_cipher_context_t *ctx,
const unsigned char input[16],
unsigned char output[16]);
/**
* \brief Clear the context.
*
* \param ctx The context to clear.
*/
void mbedtls_block_cipher_free(mbedtls_block_cipher_context_t *ctx);
#ifdef __cplusplus
}
#endif
#endif /* MBEDTLS_BLOCK_CIPHER_INTERNAL_H */