Camellia

Data Structures
struct	mbedtls_camellia_context
	CAMELLIA context structure. More...

Macros
#define	MBEDTLS_CAMELLIA_ENCRYPT   1
	Constant to select camellia encryption. More...
#define	MBEDTLS_CAMELLIA_DECRYPT   0
	Constant to select camellia decryption. More...
#define	MBEDTLS_ERR_CAMELLIA_BAD_INPUT_DATA   -0x0024
	Bad input data. More...
#define	MBEDTLS_ERR_CAMELLIA_INVALID_INPUT_LENGTH   -0x0026
	Invalid data input length. More...
#define	MBEDTLS_ERR_CAMELLIA_HW_ACCEL_FAILED   -0x0027
	Camellia hardware accelerator failed. More...

Typedefs
typedef struct mbedtls_camellia_context	mbedtls_camellia_context
	CAMELLIA context structure. More...

Functions
void	mbedtls_camellia_init (mbedtls_camellia_context *ctx)
	Initialize a CAMELLIA context. More...
void	mbedtls_camellia_free (mbedtls_camellia_context *ctx)
	Clear a CAMELLIA context. More...
int	mbedtls_camellia_setkey_enc (mbedtls_camellia_context *ctx, const unsigned char *key, unsigned int keybits)
	Perform a CAMELLIA key schedule operation for encryption. More...
int	mbedtls_camellia_setkey_dec (mbedtls_camellia_context *ctx, const unsigned char *key, unsigned int keybits)
	Perform a CAMELLIA key schedule operation for decryption. More...
int	mbedtls_camellia_crypt_ecb (mbedtls_camellia_context *ctx, int mode, const unsigned char input[16], unsigned char output[16])
	Perform a CAMELLIA-ECB block encryption/decryption operation. More...
int	mbedtls_camellia_crypt_ctr (mbedtls_camellia_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)
	Perform a CAMELLIA-CTR buffer encryption/decryption operation. More...

Detailed Description

Macro Definition Documentation

MBEDTLS_CAMELLIA_ENCRYPT

#define MBEDTLS_CAMELLIA_ENCRYPT   1

Constant to select camellia encryption.

Definition at line 43 of file camellia.h.

MBEDTLS_CAMELLIA_DECRYPT

#define MBEDTLS_CAMELLIA_DECRYPT   0

Constant to select camellia decryption.

Definition at line 44 of file camellia.h.

MBEDTLS_ERR_CAMELLIA_BAD_INPUT_DATA

#define MBEDTLS_ERR_CAMELLIA_BAD_INPUT_DATA   -0x0024

Bad input data.

Definition at line 49 of file camellia.h.

MBEDTLS_ERR_CAMELLIA_INVALID_INPUT_LENGTH

#define MBEDTLS_ERR_CAMELLIA_INVALID_INPUT_LENGTH   -0x0026

Invalid data input length.

Definition at line 51 of file camellia.h.

MBEDTLS_ERR_CAMELLIA_HW_ACCEL_FAILED

#define MBEDTLS_ERR_CAMELLIA_HW_ACCEL_FAILED   -0x0027

Camellia hardware accelerator failed.

Definition at line 55 of file camellia.h.

Typedef Documentation

mbedtls_camellia_context

typedef struct mbedtls_camellia_context mbedtls_camellia_context

CAMELLIA context structure.

Function Documentation

mbedtls_camellia_init()

void mbedtls_camellia_init

(

mbedtls_camellia_context *

ctx

)

Initialize a CAMELLIA context.

Parameters

ctx	The CAMELLIA context to be initialized. This must not be NULL.

mbedtls_camellia_free()

void mbedtls_camellia_free

(

mbedtls_camellia_context *

ctx

)

Clear a CAMELLIA context.

Parameters

ctx	The CAMELLIA context to be cleared. This may be NULL, in which case this function returns immediately. If it is not NULL, it must be initialized.

mbedtls_camellia_setkey_enc()

int mbedtls_camellia_setkey_enc	(	mbedtls_camellia_context *	ctx,
		const unsigned char *	key,
		unsigned int	keybits
	)

Perform a CAMELLIA key schedule operation for encryption.

Parameters

ctx	The CAMELLIA context to use. This must be initialized.
key	The encryption key to use. This must be a readable buffer of size keybits Bits.
keybits	The length of key in Bits. This must be either 128, 192 or 256.

Returns

0 if successful.

A negative error code on failure.

mbedtls_camellia_setkey_dec()

int mbedtls_camellia_setkey_dec	(	mbedtls_camellia_context *	ctx,
		const unsigned char *	key,
		unsigned int	keybits
	)

Perform a CAMELLIA key schedule operation for decryption.

Parameters

ctx	The CAMELLIA context to use. This must be initialized.
key	The decryption key. This must be a readable buffer of size keybits Bits.
keybits	The length of key in Bits. This must be either 128, 192 or 256.

Returns

0 if successful.

A negative error code on failure.

mbedtls_camellia_crypt_ecb()

int mbedtls_camellia_crypt_ecb	(	mbedtls_camellia_context *	ctx,
		int	mode,
		const unsigned char	input[16],
		unsigned char	output[16]
	)

Perform a CAMELLIA-ECB block encryption/decryption operation.

Parameters

ctx	The CAMELLIA context to use. This must be initialized and bound to a key.
mode	The mode of operation. This must be either MBEDTLS_CAMELLIA_ENCRYPT or MBEDTLS_CAMELLIA_DECRYPT.
input	The input block. This must be a readable buffer of size 16 Bytes.
output	The output block. This must be a writable buffer of size 16 Bytes.

Returns

0 if successful.

A negative error code on failure.

mbedtls_camellia_crypt_ctr()

int mbedtls_camellia_crypt_ctr	(	mbedtls_camellia_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
	)

Perform a CAMELLIA-CTR buffer encryption/decryption operation.

*note Due to the nature of CTR mode, you should use the same key for both encryption and decryption. In particular, calls to this function should be preceded by a key-schedule via mbedtls_camellia_setkey_enc() regardless of whether mode is MBEDTLS_CAMELLIA_ENCRYPT or MBEDTLS_CAMELLIA_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 nonce_counter and nc_off to 0 for the first call, and then preserve the values of nonce_counter, nc_off and 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.

1. You can encrypt separate messages by dividing the 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 nonce_counter to your chosen nonce value, the last four to 0, and nc_off to 0 (which will cause 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 a CAMELLIA block is 16 Bytes.

Warning

Upon return, 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.

Parameters

ctx	The CAMELLIA context to use. This must be initialized and bound to a key.
length	The length of the input data input in Bytes. Any value is allowed.
nc_off	The offset in the current stream_block (for resuming within current cipher stream). The offset pointer to should be 0 at the start of a stream. It is updated at the end of this call.
nonce_counter	The 128-bit nonce and counter. This must be a read/write buffer of length 16 Bytes.
stream_block	The saved stream-block for resuming. This must be a read/write buffer of length 16 Bytes.
input	The input data stream. This must be a readable buffer of size length Bytes.
output	The output data stream. This must be a writable buffer of size length Bytes.

Returns

0 if successful.

A negative error code on failure.