aes.h File Reference

This file contains AES definitions and functions. More...

#include "config.h"
#include <stddef.h>
#include <stdint.h>

Include dependency graph for aes.h:

This graph shows which files directly or indirectly include this file:

Go to the source code of this file.

Data Structures
struct	mbedtls_aes_context
	The AES context-type definition. More...

Macros
#define	MBEDTLS_AES_ENCRYPT   1
#define	MBEDTLS_AES_DECRYPT   0
#define	MBEDTLS_ERR_AES_INVALID_KEY_LENGTH   -0x0020
#define	MBEDTLS_ERR_AES_INVALID_INPUT_LENGTH   -0x0022
#define	MBEDTLS_ERR_AES_FEATURE_UNAVAILABLE   -0x0023
#define	MBEDTLS_ERR_AES_HW_ACCEL_FAILED   -0x0025
#define	MBEDTLS_DEPRECATED

Functions
void	mbedtls_aes_init (mbedtls_aes_context *ctx)
	This function initializes the specified AES context. More...
void	mbedtls_aes_free (mbedtls_aes_context *ctx)
	This function releases and clears the specified AES context. More...
int	mbedtls_aes_setkey_enc (mbedtls_aes_context *ctx, const unsigned char *key, unsigned int keybits)
	This function sets the encryption key. More...
int	mbedtls_aes_setkey_dec (mbedtls_aes_context *ctx, const unsigned char *key, unsigned int keybits)
	This function sets the decryption key. More...
int	mbedtls_aes_crypt_ecb (mbedtls_aes_context *ctx, int mode, const unsigned char input[16], unsigned char output[16])
	This function performs an AES single-block encryption or decryption operation. More...
int	mbedtls_aes_crypt_cbc (mbedtls_aes_context *ctx, int mode, size_t length, unsigned char iv[16], const unsigned char *input, unsigned char *output)
	This function performs an AES-CBC encryption or decryption operation on full blocks. More...
int	mbedtls_aes_crypt_cfb128 (mbedtls_aes_context *ctx, int mode, size_t length, size_t *iv_off, unsigned char iv[16], const unsigned char *input, unsigned char *output)
	This function performs an AES-CFB128 encryption or decryption operation. More...
int	mbedtls_aes_crypt_cfb8 (mbedtls_aes_context *ctx, int mode, size_t length, unsigned char iv[16], const unsigned char *input, unsigned char *output)
	This function performs an AES-CFB8 encryption or decryption operation. More...
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)
	This function performs an AES-CTR encryption or decryption operation. More...
int	mbedtls_internal_aes_encrypt (mbedtls_aes_context *ctx, const unsigned char input[16], unsigned char output[16])
	Internal AES block encryption function. This is only exposed to allow overriding it using MBEDTLS_AES_ENCRYPT_ALT. More...
int	mbedtls_internal_aes_decrypt (mbedtls_aes_context *ctx, const unsigned char input[16], unsigned char output[16])
	Internal AES block decryption function. This is only exposed to allow overriding it using see MBEDTLS_AES_DECRYPT_ALT. More...
MBEDTLS_DEPRECATED void	mbedtls_aes_encrypt (mbedtls_aes_context *ctx, const unsigned char input[16], unsigned char output[16])
	Deprecated internal AES block encryption function without return value. More...
MBEDTLS_DEPRECATED void	mbedtls_aes_decrypt (mbedtls_aes_context *ctx, const unsigned char input[16], unsigned char output[16])
	Deprecated internal AES block decryption function without return value. More...
int	mbedtls_aes_self_test (int verbose)
	Checkup routine. More...

Detailed Description

This file contains AES definitions and functions.

The Advanced Encryption Standard (AES) specifies a FIPS-approved cryptographic algorithm that can be used to protect electronic data.

The AES algorithm is a symmetric block cipher that can encrypt and decrypt information. For more information, see FIPS Publication 197: Advanced Encryption Standard and ISO/IEC 18033-2:2006: Information technology – Security techniques – Encryption algorithms – Part 2: Asymmetric ciphers.

Definition in file aes.h.

Macro Definition Documentation

#define MBEDTLS_AES_DECRYPT   0

AES decryption.

Definition at line 50 of file aes.h.

#define MBEDTLS_AES_ENCRYPT   1

AES encryption.

Definition at line 49 of file aes.h.

#define MBEDTLS_DEPRECATED

Definition at line 370 of file aes.h.

#define MBEDTLS_ERR_AES_FEATURE_UNAVAILABLE   -0x0023

Feature not available. For example, an unsupported AES key size.

Definition at line 57 of file aes.h.

#define MBEDTLS_ERR_AES_HW_ACCEL_FAILED   -0x0025

AES hardware accelerator failed.

Definition at line 58 of file aes.h.

#define MBEDTLS_ERR_AES_INVALID_INPUT_LENGTH   -0x0022

Invalid data input length.

Definition at line 54 of file aes.h.

#define MBEDTLS_ERR_AES_INVALID_KEY_LENGTH   -0x0020

Invalid key length.

Definition at line 53 of file aes.h.

Function Documentation

int mbedtls_aes_crypt_cbc	(	mbedtls_aes_context *	ctx,
		int	mode,
		size_t	length,
		unsigned char	iv[16],
		const unsigned char *	input,
		unsigned char *	output
	)

This function performs an AES-CBC encryption or decryption operation on full blocks.

    It performs the operation defined in the \p mode
    parameter (encrypt/decrypt), on the input data buffer defined in
    the \p input parameter.

    It can be called as many times as needed, until all the input
    data is processed. mbedtls_aes_init(), and either
    mbedtls_aes_setkey_enc() or mbedtls_aes_setkey_dec() must be called
    before the first call to this API with the same context.

Note

This function operates on aligned blocks, that is, the input size must be a multiple of the AES block size of 16 Bytes.

Upon exit, the content of the IV 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. If you need to retain the contents of the IV, you should either save it manually or use the cipher module instead.

Parameters

ctx	The AES context to use for encryption or decryption.
mode	The AES operation: MBEDTLS_AES_ENCRYPT or MBEDTLS_AES_DECRYPT.
length	The length of the input data in Bytes. This must be a multiple of the block size (16 Bytes).
iv	Initialization vector (updated after use).
input	The buffer holding the input data.
output	The buffer holding the output data.

Returns

0 on success.

MBEDTLS_ERR_AES_INVALID_INPUT_LENGTH on failure.

int mbedtls_aes_crypt_cfb128	(	mbedtls_aes_context *	ctx,
		int	mode,
		size_t	length,
		size_t *	iv_off,
		unsigned char	iv[16],
		const unsigned char *	input,
		unsigned char *	output
	)

This function performs an AES-CFB128 encryption or decryption operation.

   It performs the operation defined in the \p mode
   parameter (encrypt or decrypt), on the input data buffer
   defined in the \p input parameter.

   For CFB, you must set up the context with mbedtls_aes_setkey_enc(),
   regardless of whether you are performing an encryption or decryption
   operation, that is, regardless of the \p mode parameter. This is
   because CFB mode uses the same key schedule for encryption and
   decryption.

Note

Upon exit, the content of the IV 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. If you need to retain the contents of the IV, you must either save it manually or use the cipher module instead.

Parameters

ctx	The AES context to use for encryption or decryption.
mode	The AES operation: MBEDTLS_AES_ENCRYPT or MBEDTLS_AES_DECRYPT.
length	The length of the input data.
iv_off	The offset in IV (updated after use).
iv	The initialization vector (updated after use).
input	The buffer holding the input data.
output	The buffer holding the output data.

Returns

0 on success.

int mbedtls_aes_crypt_cfb8	(	mbedtls_aes_context *	ctx,
		int	mode,
		size_t	length,
		unsigned char	iv[16],
		const unsigned char *	input,
		unsigned char *	output
	)

This function performs an AES-CFB8 encryption or decryption operation.

   It 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 CFB, 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.

Note

Upon exit, the content of the IV 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. If you need to retain the contents of the IV, you should either save it manually or use the cipher module instead.

Parameters

ctx	The AES context to use for encryption or decryption.
mode	The AES operation: MBEDTLS_AES_ENCRYPT or MBEDTLS_AES_DECRYPT
length	The length of the input data.
iv	The initialization vector (updated after use).
input	The buffer holding the input data.
output	The buffer holding the output data.

Returns

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
	)

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 keep the maximum use of your counter in mind.

Parameters

ctx	The AES context to use for encryption or decryption.
length	The length of the input data.
nc_off	The offset in the current stream_block, for resuming within the current cipher stream. The offset pointer should be 0 at the start of a stream.
nonce_counter	The 128-bit nonce and counter.
stream_block	The saved stream block for resuming. This is overwritten by the function.
input	The buffer holding the input data.
output	The buffer holding the output data.

Returns

0 on success.

int mbedtls_aes_crypt_ecb	(	mbedtls_aes_context *	ctx,
		int	mode,
		const unsigned char	input[16],
		unsigned char	output[16]
	)

This function performs an AES single-block encryption or decryption operation.

            It performs the operation defined in the \p mode parameter
            (encrypt or decrypt), on the input data buffer defined in
            the \p input parameter.

            mbedtls_aes_init(), and either mbedtls_aes_setkey_enc() or
            mbedtls_aes_setkey_dec() must be called before the first
            call to this API with the same context.

Parameters

ctx	The AES context to use for encryption or decryption.
mode	The AES operation: MBEDTLS_AES_ENCRYPT or MBEDTLS_AES_DECRYPT.
input	The 16-Byte buffer holding the input data.
output	The 16-Byte buffer holding the output data.

Returns

0 on success.

MBEDTLS_DEPRECATED void mbedtls_aes_decrypt	(	mbedtls_aes_context *	ctx,
		const unsigned char	input[16],
		unsigned char	output[16]
	)

Deprecated internal AES block decryption function without return value.

Deprecated:

Superseded by mbedtls_aes_decrypt_ext() in 2.5.0.

Parameters

ctx	The AES context to use for decryption.
input	Ciphertext block.
output	Output (plaintext) block.

MBEDTLS_DEPRECATED void mbedtls_aes_encrypt	(	mbedtls_aes_context *	ctx,
		const unsigned char	input[16],
		unsigned char	output[16]
	)

Deprecated internal AES block encryption function without return value.

Deprecated:

Superseded by mbedtls_aes_encrypt_ext() in 2.5.0.

Parameters

ctx	The AES context to use for encryption.
input	Plaintext block.
output	Output (ciphertext) block.

void mbedtls_aes_free

(

mbedtls_aes_context *

ctx

)

This function releases and clears the specified AES context.

Parameters

ctx	The AES context to clear.

void mbedtls_aes_init

(

mbedtls_aes_context *

ctx

)

This function initializes the specified AES context.

            It must be the first API called before using
            the context.

Parameters

ctx	The AES context to initialize.

int mbedtls_aes_self_test

(

int

verbose

)

Checkup routine.

Returns

0 on success.

1 on failure.

int mbedtls_aes_setkey_dec	(	mbedtls_aes_context *	ctx,
		const unsigned char *	key,
		unsigned int	keybits
	)

This function sets the decryption key.

Parameters

ctx	The AES context to which the key should be bound.
key	The decryption key.
keybits	The size of data passed. Valid options are: 128 bits 192 bits 256 bits

Returns

0 on success.

MBEDTLS_ERR_AES_INVALID_KEY_LENGTH on failure.

int mbedtls_aes_setkey_enc	(	mbedtls_aes_context *	ctx,
		const unsigned char *	key,
		unsigned int	keybits
	)

This function sets the encryption key.

Parameters

ctx	The AES context to which the key should be bound.
key	The encryption key.
keybits	The size of data passed in bits. Valid options are: 128 bits 192 bits 256 bits

Returns

0 on success.

MBEDTLS_ERR_AES_INVALID_KEY_LENGTH on failure.

int mbedtls_internal_aes_decrypt	(	mbedtls_aes_context *	ctx,
		const unsigned char	input[16],
		unsigned char	output[16]
	)

Internal AES block decryption function. This is only exposed to allow overriding it using see MBEDTLS_AES_DECRYPT_ALT.

Parameters

ctx	The AES context to use for decryption.
input	The ciphertext block.
output	The output (plaintext) block.

Returns

0 on success.

int mbedtls_internal_aes_encrypt	(	mbedtls_aes_context *	ctx,
		const unsigned char	input[16],
		unsigned char	output[16]
	)

Internal AES block encryption function. This is only exposed to allow overriding it using MBEDTLS_AES_ENCRYPT_ALT.

Parameters

ctx	The AES context to use for encryption.
input	The plaintext block.
output	The output (ciphertext) block.

Returns

0 on success.