Memory-Mapped Cryptographic Acceleration Unit (mmCAU)

Overview

The mmCAU software library uses the mmCAU co-processor that is connected to the ARM Cortex-M4/M0+ Private Peripheral Bus (PPB). In this chapter, CAU refers to both CAU and mmCAU unless explicitly noted.

Purpose

The following chapter describes how to use the mmCAU software library in any application to integrate a cryptographic algorithm or hashing function supported by the software library. NXP products supported by the software library are MCU/MPUs. Check the specific Freescale product for CAU availability.

Library Features

The library is as compact and generic as possible to simplify the integration with existing cryptographic software. The library has a standard header file with ANSI C prototypes for all functions: "cau_api.h". This software library is thread safe only if CAU registers are saved on a context switch. The mmCAU software library is also compatible to ARM C compiler conventions (EABI). All pointers passed to mmCAU API functions (input and output data blocks, keys, key schedules, and so on) are aligned to 0-modulo-4 addresses.
For applications that don't need to deal with the aligned addresses, a simple wrapper layer is provided. The wrapper layer consists of the "fsl_mmcau.h" header file and "fsl_mmcau.c" source code file. The only function of the wrapper layer is that it supports unaligned addresses
. The CAU library supports the following encryption/decryption algorithms and hashing functions:

• AES128
• AES192
• AES256
• DES
• MD5
• SHA1
• SHA256

Note: 3DES crypto algorithms are supported by calling the corresponding DES crypto function three times. Hardware support for SHA256 is only present in the CAU version 2. See the appropriate MCU/MPU reference manual for details about availability. Additionally, the cau_sha256_initialize_output() function checks the hardware revision and returns a (-1) value if the CAU lacks SHA256 support.

CAU and mmCAU software library overview

Table 1 shows the crypto algorithms and hashing functions included in the software library:

Crypto Algorithms	AES128 AES192 AES256	cau_aes_set_key
		cau_aes_encrypt
		cau_aes_decrypt
	DES/3DES	cau_des_chk_parity
		cau_des_encrypt
		cau_des_decrypt
Hashing Functions	MD5	cau_md5_initialize_output
		cau_md5_hash_n
		cau_md5_update
		cau_md5_hash
	SHA1	cau_sha1_initialize_output
		cau_sha1_hash_n
		cau_sha1_update
		cau_sha1_hash
	SHA256	cau_sha256_initialize_output
		cau_sha256_hash_n
		cau_sha256_update
		cau_sha256_hash

Table 1: Library Overview

mmCAU software library usage

The software library contains the following files:

File	Description
cau_api.h	CAU and mmCAU header file
lib_mmcau.a	mmCAU library

Table 2: File Description

The header file and lib_mmcau.a must always be included in the project.

Functions
void	cau_aes_set_key (const unsigned char *key, const int key_size, unsigned char *key_sch)
	AES: Performs an AES key expansion. More...
void	cau_aes_encrypt (const unsigned char *in, const unsigned char *key_sch, const int nr, unsigned char *out)
	AES: Encrypts a single 16 byte block. More...
void	cau_aes_decrypt (const unsigned char *in, const unsigned char *key_sch, const int nr, unsigned char *out)
	AES: Decrypts a single 16-byte block. More...
int	cau_des_chk_parity (const unsigned char *key)
	DES: Checks key parity. More...
void	cau_des_encrypt (const unsigned char *in, const unsigned char *key, unsigned char *out)
	DES: Encrypts a single 8-byte block. More...
void	cau_des_decrypt (const unsigned char *in, const unsigned char *key, unsigned char *out)
	DES: Decrypts a single 8-byte block. More...
void	cau_md5_initialize_output (const unsigned char *md5_state)
	MD5: Initializes the MD5 state variables. More...
void	cau_md5_hash_n (const unsigned char *msg_data, const int num_blks, unsigned char *md5_state)
	MD5: Updates MD5 state variables with n message blocks. More...
void	cau_md5_update (const unsigned char *msg_data, const int num_blks, unsigned char *md5_state)
	MD5: Updates MD5 state variables. More...
void	cau_md5_hash (const unsigned char *msg_data, unsigned char *md5_state)
	MD5: Updates MD5 state variables with one message block. More...
void	cau_sha1_initialize_output (const unsigned int *sha1_state)
	SHA1: Initializes the SHA1 state variables. More...
void	cau_sha1_hash_n (const unsigned char *msg_data, const int num_blks, unsigned int *sha1_state)
	SHA1: Updates SHA1 state variables with n message blocks. More...
void	cau_sha1_update (const unsigned char *msg_data, const int num_blks, unsigned int *sha1_state)
	SHA1: Updates SHA1 state variables. More...
void	cau_sha1_hash (const unsigned char *msg_data, unsigned int *sha1_state)
	SHA1: Updates SHA1 state variables with one message block. More...
int	cau_sha256_initialize_output (const unsigned int *output)
	SHA256: Initializes the SHA256 state variables. More...
void	cau_sha256_hash_n (const unsigned char *input, const int num_blks, unsigned int *output)
	SHA256: Updates SHA256 state variables with n message blocks. More...
void	cau_sha256_update (const unsigned char *input, const int num_blks, unsigned int *output)
	SHA256: Updates SHA256 state variables. More...
void	cau_sha256_hash (const unsigned char *input, unsigned int *output)
	SHA256: Updates SHA256 state variables with one message block. More...
status_t	MMCAU_AES_SetKey (const uint8_t *key, const size_t keySize, uint8_t *keySch)
	AES: Performs an AES key expansion. More...
status_t	MMCAU_AES_EncryptEcb (const uint8_t *in, const uint8_t *keySch, uint32_t aesRounds, uint8_t *out)
	AES: Encrypts a single 16 byte block. More...
status_t	MMCAU_AES_DecryptEcb (const uint8_t *in, const uint8_t *keySch, uint32_t aesRounds, uint8_t *out)
	AES: Decrypts a single 16-byte block. More...
status_t	MMCAU_DES_ChkParity (const uint8_t *key)
	DES: Checks the key parity. More...
status_t	MMCAU_DES_EncryptEcb (const uint8_t *in, const uint8_t *key, uint8_t *out)
	DES: Encrypts a single 8-byte block. More...
status_t	MMCAU_DES_DecryptEcb (const uint8_t *in, const uint8_t *key, uint8_t *out)
	DES: Decrypts a single 8-byte block. More...
status_t	MMCAU_MD5_InitializeOutput (uint32_t *md5State)
	MD5: Initializes the MD5 state variables. More...
status_t	MMCAU_MD5_HashN (const uint8_t *msgData, uint32_t numBlocks, uint32_t *md5State)
	MD5: Updates the MD5 state variables with n message blocks. More...
status_t	MMCAU_MD5_Update (const uint8_t *msgData, uint32_t numBlocks, uint32_t *md5State)
	MD5: Updates the MD5 state variables. More...
status_t	MMCAU_SHA1_InitializeOutput (uint32_t *sha1State)
	SHA1: Initializes the SHA1 state variables. More...
status_t	MMCAU_SHA1_HashN (const uint8_t *msgData, uint32_t numBlocks, uint32_t *sha1State)
	SHA1: Updates the SHA1 state variables with n message blocks. More...
status_t	MMCAU_SHA1_Update (const uint8_t *msgData, uint32_t numBlocks, uint32_t *sha1State)
	SHA1: Updates the SHA1 state variables. More...
status_t	MMCAU_SHA256_InitializeOutput (uint32_t *sha256State)
	SHA256: Initializes the SHA256 state variables. More...
status_t	MMCAU_SHA256_HashN (const uint8_t *input, uint32_t numBlocks, uint32_t *sha256State)
	SHA256: Updates the SHA256 state variables with n message blocks. More...
status_t	MMCAU_SHA256_Update (const uint8_t *input, uint32_t numBlocks, uint32_t *sha256State)
	SHA256: Updates SHA256 state variables. More...

Function Documentation

void cau_aes_set_key	(	const unsigned char *	key,
		const int	key_size,
		unsigned char *	key_sch
	)

This function performs an AES key expansion

Parameters

	key	Pointer to input key (128, 192, 256 bits in length).
	key_size	Key size in bits (128, 192, 256)
[out]	key_sch	Pointer to key schedule output (44, 52, 60 longwords)

Note

All pointers must have word (4 bytes) alignment

Table below shows the requirements for the cau_aes_set_key() function when using AES128, AES192 or AES256.

[in] Key Size (bits)	[out] Key Schedule Size (32 bit data values)
128	44
192	52
256	60

void cau_aes_encrypt	(	const unsigned char *	in,
		const unsigned char *	key_sch,
		const int	nr,
		unsigned char *	out
	)

This function encrypts a single 16-byte block for AES128, AES192 and AES256

Parameters

	in	Pointer to 16-byte block of input plaintext
	key_sch	Pointer to key schedule (44, 52, 60 longwords)
	nr	Number of AES rounds (10, 12, 14 = f(key_schedule))
[out]	out	Pointer to 16-byte block of output ciphertext

Note

All pointers must have word (4 bytes) alignment

Input and output blocks may overlap.
Table below shows the requirements for the cau_aes_encrypt()/cau_aes_decrypt() function when using AES128, AES192 or AES256.

Block Cipher	[in] Key Schedule Size (longwords)	[in] Number of AES rounds
AES128	44	10
AES192	52	12
AES256	60	14

void cau_aes_decrypt	(	const unsigned char *	in,
		const unsigned char *	key_sch,
		const int	nr,
		unsigned char *	out
	)

This function decrypts a single 16-byte block for AES128, AES192 and AES256

Parameters

	in	Pointer to 16-byte block of input ciphertext
	key_sch	Pointer to key schedule (44, 52, 60 longwords)
	nr	Number of AES rounds (10, 12, 14 = f(key_schedule))
[out]	out	Pointer to 16-byte block of output plaintext

Note

All pointers must have word (4 bytes) alignment

Input and output blocks may overlap.
Table below shows the requirements for the cau_aes_encrypt()/cau_aes_decrypt() function when using AES128, AES192 or AES256.

Block Cipher	[in] Key Schedule Size (longwords)	[in] Number of AES rounds
AES128	44	10
AES192	52	12
AES256	60	14

int cau_des_chk_parity

(

const unsigned char *

key

)

This function checks the parity of a DES key

Parameters

key	64-bit DES key with parity bits. Must have word (4 bytes) alignment.

Returns

0 no error

-1 parity error

void cau_des_encrypt	(	const unsigned char *	in,
		const unsigned char *	key,
		unsigned char *	out
	)

This function encrypts a single 8-byte block with DES algorithm.

Parameters

	in	Pointer to 8-byte block of input plaintext
	key	Pointer to 64-bit DES key with parity bits
[out]	out	Pointer to 8-byte block of output ciphertext

Note

All pointers must have word (4 bytes) alignment

Input and output blocks may overlap.

void cau_des_decrypt	(	const unsigned char *	in,
		const unsigned char *	key,
		unsigned char *	out
	)

This function decrypts a single 8-byte block with DES algorithm.

Parameters

	in	Pointer to 8-byte block of input ciphertext
	key	Pointer to 64-bit DES key with parity bits
[out]	out	Pointer to 8-byte block of output plaintext

Note

All pointers must have word (4 bytes) alignment

Input and output blocks may overlap.

void cau_md5_initialize_output

(

const unsigned char *

md5_state

)

This function initializes the MD5 state variables. The output can be used as input to cau_md5_hash() and cau_md5_hash_n().

Parameters

[out]

md5_state

Pointer to 128-bit block of md5 state variables: a,b,c,d

Note

All pointers must have word (4 bytes) alignment

void cau_md5_hash_n	(	const unsigned char *	msg_data,
		const int	num_blks,
		unsigned char *	md5_state
	)

This function updates MD5 state variables for one or more input message blocks

Parameters

	msg_data	Pointer to start of input message data
	num_blks	Number of 512-bit blocks to process
[in,out]	md5_state	Pointer to 128-bit block of MD5 state variables: a,b,c,d

Note

All pointers must have word (4 bytes) alignment

Input message and digest output blocks must not overlap. The cau_md5_initialize_output() function must be called when starting a new hash. Useful when handling non-contiguous input message blocks.

void cau_md5_update	(	const unsigned char *	msg_data,
		const int	num_blks,
		unsigned char *	md5_state
	)

This function updates MD5 state variables for one or more input message blocks. It starts a new hash as it internally calls cau_md5_initialize_output() first.

Parameters

	msg_data	Pointer to start of input message data
	num_blks	Number of 512-bit blocks to process
[out]	md5_state	Pointer to 128-bit block of MD5 state variables: a,b,c,d

Note

All pointers must have word (4 bytes) alignment

Input message and digest output blocks must not overlap. The cau_md5_initialize_output() function is not required to be called as it is called internally to start a new hash. All input message blocks must be contiguous.

void cau_md5_hash	(	const unsigned char *	msg_data,
		unsigned char *	md5_state
	)

This function updates MD5 state variables for one input message block

Parameters

	msg_data	Pointer to start of 512-bits of input message data
[in,out]	md5_state	Pointer to 128-bit block of MD5 state variables: a,b,c,d

Note

All pointers must have word (4 bytes) alignment

Input message and digest output blocks must not overlap. The cau_md5_initialize_output() function must be called when starting a new hash.

void cau_sha1_initialize_output

(

const unsigned int *

sha1_state

)

This function initializes the SHA1 state variables. The output can be used as input to cau_sha1_hash() and cau_sha1_hash_n().

Parameters

[out]

sha1_state

Pointer to 160-bit block of SHA1 state variables: a,b,c,d,e

Note

All pointers must have word (4 bytes) alignment

void cau_sha1_hash_n	(	const unsigned char *	msg_data,
		const int	num_blks,
		unsigned int *	sha1_state
	)

This function updates SHA1 state variables for one or more input message blocks

Parameters

	msg_data	Pointer to start of input message data
	num_blks	Number of 512-bit blocks to process
[in,out]	sha1_state	Pointer to 160-bit block of SHA1 state variables: a,b,c,d,e

Note

All pointers must have word (4 bytes) alignment

Input message and digest output blocks must not overlap. The cau_sha1_initialize_output() function must be called when starting a new hash. Useful when handling non-contiguous input message blocks.

void cau_sha1_update	(	const unsigned char *	msg_data,
		const int	num_blks,
		unsigned int *	sha1_state
	)

This function updates SHA1 state variables for one or more input message blocks. It starts a new hash as it internally calls cau_sha1_initialize_output() first.

Parameters

	msg_data	Pointer to start of input message data
	num_blks	Number of 512-bit blocks to process
[out]	sha1_state	Pointer to 160-bit block of SHA1 state variables: a,b,c,d,e

Note

All pointers must have word (4 bytes) alignment

Input message and digest output blocks must not overlap. The cau_sha1_initialize_output() function is not required to be called as it is called internally to start a new hash. All input message blocks must be contiguous.

void cau_sha1_hash	(	const unsigned char *	msg_data,
		unsigned int *	sha1_state
	)

This function updates SHA1 state variables for one input message block

Parameters

	msg_data	Pointer to start of 512-bits of input message data
[in,out]	sha1_state	Pointer to 160-bit block of SHA1 state variables: a,b,c,d,e

Note

All pointers must have word (4 bytes) alignment

Input message and digest output blocks must not overlap. The cau_sha1_initialize_output() function must be called when starting a new hash.

int cau_sha256_initialize_output

(

const unsigned int *

output

)

This function initializes the SHA256 state variables. The output can be used as input to cau_sha256_hash() and cau_sha256_hash_n().

Parameters

[out]

output

Pointer to 256-bit block of SHA2 state variables a,b,c,d,e,f,g,h

Note

All pointers must have word (4 bytes) alignment

Returns

0 No error. CAU hardware support for SHA256 is present.

-1 Error. CAU hardware support for SHA256 is not present.

void cau_sha256_hash_n	(	const unsigned char *	input,
		const int	num_blks,
		unsigned int *	output
	)

This function updates SHA256 state variables for one or more input message blocks

Parameters

	input	Pointer to start of input message data
	num_blks	Number of 512-bit blocks to process
[in,out]	output	Pointer to 256-bit block of SHA2 state variables: a,b,c,d,e,f,g,h

Note

All pointers must have word (4 bytes) alignment

Input message and digest output blocks must not overlap. The cau_sha256_initialize_output() function must be called when starting a new hash. Useful when handling non-contiguous input message blocks.

void cau_sha256_update	(	const unsigned char *	input,
		const int	num_blks,
		unsigned int *	output
	)

This function updates SHA256 state variables for one or more input message blocks. It starts a new hash as it internally calls cau_sha256_initialize_output() first.

Parameters

	input	Pointer to start of input message data
	num_blks	Number of 512-bit blocks to process
[out]	output	Pointer to 256-bit block of SHA2 state variables: a,b,c,d,e,f,g,h

Note

All pointers must have word (4 bytes) alignment

Input message and digest output blocks must not overlap. The cau_sha256_initialize_output() function is not required to be called as it is called internally to start a new hash. All input message blocks must be contiguous.

void cau_sha256_hash	(	const unsigned char *	input,
		unsigned int *	output
	)

This function updates SHA256 state variables for one input message block

Parameters

	input	Pointer to start of 512-bits of input message data
[in,out]	output	Pointer to 256-bit block of SHA2 state variables: a,b,c,d,e,f,g,h

Note

All pointers must have word (4 bytes) alignment

Input message and digest output blocks must not overlap. The cau_sha256_initialize_output() function must be called when starting a new hash.

status_t MMCAU_AES_SetKey	(	const uint8_t *	key,
		const size_t	keySize,
		uint8_t *	keySch
	)

This function performs an AES key expansion.

Parameters

	key	Pointer to input key (128, 192, 256 bits in length).
	keySize	Key size in bytes (16, 24, 32)
[out]	keySch	Pointer to key schedule output (44, 52, 60 longwords)

Note

Table below shows the requirements for the MMCAU_AES_SetKey() function when using AES128, AES192, or AES256.

[in] Key Size (bits)	[out] Key Schedule Size (32 bit data values)
128	44
192	52
256	60

Returns

Status of the operation. (kStatus_Success, kStatus_InvalidArgument, kStatus_Fail)

status_t MMCAU_AES_EncryptEcb	(	const uint8_t *	in,
		const uint8_t *	keySch,
		uint32_t	aesRounds,
		uint8_t *	out
	)

This function encrypts a single 16-byte block for AES128, AES192, and AES256.

Parameters

	in	Pointer to 16-byte block of input plaintext.
	keySch	Pointer to key schedule (44, 52, 60 longwords).
	aesRounds	Number of AES rounds (10, 12, 14 = f(key_schedule)).
[out]	out	Pointer to 16-byte block of output ciphertext.

Note

Input and output blocks may overlap.
Table below shows the requirements for the MMCAU_AES_EncryptEcb()/MMCAU_AES_DecryptEcb() function when using AES128, AES192 or AES256.

Block Cipher	[in] Key Schedule Size (longwords)	[in] Number of AES rounds
AES128	44	10
AES192	52	12
AES256	60	14

Returns

Status of the operation. (kStatus_Success, kStatus_InvalidArgument, kStatus_Fail)

status_t MMCAU_AES_DecryptEcb	(	const uint8_t *	in,
		const uint8_t *	keySch,
		uint32_t	aesRounds,
		uint8_t *	out
	)

This function decrypts a single 16-byte block for AES128, AES192, and AES256.

Parameters

	in	Pointer to 16-byte block of input ciphertext.
	keySch	Pointer to key schedule (44, 52, 60 longwords).
	aesRounds	Number of AES rounds (10, 12, 14 = f(key_schedule)).
[out]	out	Pointer to 16-byte block of output plaintext.

Note

Input and output blocks may overlap.
Table below shows the requirements for the cau_aes_encrypt()/cau_aes_decrypt(). function when using AES128, AES192 or AES256.

Block Cipher	[in] Key Schedule Size (longwords)	[in] Number of AES rounds
AES128	44	10
AES192	52	12
AES256	60	14

Returns

Status of the operation. (kStatus_Success, kStatus_InvalidArgument, kStatus_Fail)

status_t MMCAU_DES_ChkParity

(

const uint8_t *

key

)

This function checks the parity of a DES key.

Parameters

key	64-bit DES key with parity bits.

Returns

kStatus_Success No error.

kStatus_Fail Parity error.

kStatus_InvalidArgument Key argument is NULL.

status_t MMCAU_DES_EncryptEcb	(	const uint8_t *	in,
		const uint8_t *	key,
		uint8_t *	out
	)

This function encrypts a single 8-byte block with the DES algorithm.

Parameters

	in	Pointer to 8-byte block of input plaintext.
	key	Pointer to 64-bit DES key with parity bits.
[out]	out	Pointer to 8-byte block of output ciphertext.

Note

Input and output blocks may overlap.

Returns

Status of the operation. (kStatus_Success, kStatus_InvalidArgument, kStatus_Fail)

status_t MMCAU_DES_DecryptEcb	(	const uint8_t *	in,
		const uint8_t *	key,
		uint8_t *	out
	)

This function decrypts a single 8-byte block with the DES algorithm.

Parameters

	in	Pointer to 8-byte block of input ciphertext.
	key	Pointer to 64-bit DES key with parity bits.
[out]	out	Pointer to 8-byte block of output plaintext.

Note

Input and output blocks may overlap.

Returns

Status of the operation. (kStatus_Success, kStatus_InvalidArgument, kStatus_Fail)

status_t MMCAU_MD5_InitializeOutput

(

uint32_t *

md5State

)

This function initializes the MD5 state variables. The output can be used as input to MMCAU_MD5_HashN().

Parameters

[out]

md5State

Pointer to 128-bit block of md5 state variables: a,b,c,d

status_t MMCAU_MD5_HashN	(	const uint8_t *	msgData,
		uint32_t	numBlocks,
		uint32_t *	md5State
	)

This function updates the MD5 state variables for one or more input message blocks.

Parameters

	msgData	Pointer to start of input message data.
	numBlocks	Number of 512-bit blocks to process.
[in,out]	md5State	Pointer to 128-bit block of MD5 state variables: a, b, c, d.

Note

Input message and digest output blocks must not overlap. The MMCAU_MD5_InitializeOutput() function must be called when starting a new hash. Useful when handling non-contiguous input message blocks.

status_t MMCAU_MD5_Update	(	const uint8_t *	msgData,
		uint32_t	numBlocks,
		uint32_t *	md5State
	)

This function updates the MD5 state variables for one or more input message blocks. It starts a new hash as it internally calls MMCAU_MD5_InitializeOutput() first.

Parameters

	msgData	Pointer to start of input message data.
	numBlocks	Number of 512-bit blocks to process.
[out]	md5State	Pointer to 128-bit block of MD5 state variables: a, b, c, d.

Note

Input message and digest output blocks must not overlap. The MMCAU_MD5_InitializeOutput() function is not required to be called as it is called internally to start a new hash. All input message blocks must be contiguous.

status_t MMCAU_SHA1_InitializeOutput

(

uint32_t *

sha1State

)

This function initializes the SHA1 state variables. The output can be used as input to MMCAU_SHA1_HashN().

Parameters

[out]

sha1State

Pointer to 160-bit block of SHA1 state variables: a, b, c, d, e.

status_t MMCAU_SHA1_HashN	(	const uint8_t *	msgData,
		uint32_t	numBlocks,
		uint32_t *	sha1State
	)

This function updates the SHA1 state variables for one or more input message blocks.

Parameters

	msgData	Pointer to start of input message data.
	numBlocks	Number of 512-bit blocks to process.
[in,out]	sha1State	Pointer to 160-bit block of SHA1 state variables: a, b, c, d, e.

Note

Input message and digest output blocks must not overlap. The MMCAU_SHA1_InitializeOutput() function must be called when starting a new hash. Useful when handling non-contiguous input message blocks.

status_t MMCAU_SHA1_Update	(	const uint8_t *	msgData,
		uint32_t	numBlocks,
		uint32_t *	sha1State
	)

This function updates the SHA1 state variables for one or more input message blocks. It starts a new hash as it internally calls MMCAU_SHA1_InitializeOutput() first.

Parameters

	msgData	Pointer to start of input message data.
	numBlocks	Number of 512-bit blocks to process.
[out]	sha1State	Pointer to 160-bit block of SHA1 state variables: a, b, c, d, e.

Note

Input message and digest output blocks must not overlap. The MMCAU_SHA1_InitializeOutput() function is not required to be called as it is called internally to start a new hash. All input message blocks must be contiguous.

status_t MMCAU_SHA256_InitializeOutput

(

uint32_t *

sha256State

)

This function initializes the SHA256 state variables. The output can be used as input to MMCAU_SHA256_HashN().

Parameters

[out]

sha256State

Pointer to 256-bit block of SHA2 state variables a, b, c, d, e, f, g, h.

Returns

kStatus_Success No error. CAU hardware support for SHA256 is present.

kStatus_Fail Error. CAU hardware support for SHA256 is not present.

kStatus_InvalidArgument Error. sha256State is NULL.

status_t MMCAU_SHA256_HashN	(	const uint8_t *	input,
		uint32_t	numBlocks,
		uint32_t *	sha256State
	)

This function updates SHA256 state variables for one or more input message blocks.

Parameters

	input	Pointer to start of input message data.
	numBlocks	Number of 512-bit blocks to process.
[in,out]	sha256State	Pointer to 256-bit block of SHA2 state variables: a, b, c, d, e, f, g, h.

Note

Input message and digest output blocks must not overlap. The MMCAU_SHA256_InitializeOutput() function must be called when starting a new hash. Useful when handling non-contiguous input message blocks.

status_t MMCAU_SHA256_Update	(	const uint8_t *	input,
		uint32_t	numBlocks,
		uint32_t *	sha256State
	)

This function updates the SHA256 state variables for one or more input message blocks. It starts a new hash as it internally calls cau_sha256_initialize_output() first.

Parameters

	input	Pointer to start of input message data.
	numBlocks	Number of 512-bit blocks to process.
[out]	sha256State	Pointer to 256-bit block of SHA2 state variables: a, b, c, d, e, f, g, h.

Note

Input message and digest output blocks must not overlap. The MMCAU_SHA256_InitializeOutput() function is not required to be called. as it is called internally to start a new hash. All input message blocks must be contiguous.