Sha256Class Class Reference

#include <sha256.h>

Inheritance diagram for Sha256Class:

Classes
union	_buffer
union	_state

Public Member Functions
void	init (void)
void	initHmac (const uint8_t *secret, int secretLength)
uint8_t *	result (void)
uint8_t *	resultHmac (void)
virtual size_t	write (uint8_t)
size_t	write_L (const char *str)
size_t	write_L (const uint8_t *buffer, size_t size)
size_t	print (const char *str)
double	millis ()
virtual size_t	write (uint8_t)

Private Member Functions
void	pad ()
void	addUncounted (uint8_t data)
void	hashBlock ()
uint32_t	ror32 (uint32_t number, uint8_t bits)

Private Attributes
_buffer	buffer
uint8_t	bufferOffset
_state	state
uint32_t	byteCount
uint8_t	keyBuffer [BLOCK_LENGTH]
uint8_t	innerHash [HASH_LENGTH]
timeval	tv

Member Function Documentation

void Sha256Class::init

(

void

)

Initialized the SHA256 process Set the counter and buffers

void Sha256Class::initHmac	(	const uint8_t *	secret,
		int	secretLength
	)

initializes the HMAC process for SHA-256

Parameters

secret	The key to be used
secretLength	The length of the key

uint8_t * Sha256Class::result

(

void

)

Pads the last block and finalizes the hash.

Returns

returns the hash

uint8_t * Sha256Class::resultHmac

(

void

)

Pads the last block and finalizes the hash.

Returns

returns the hash

size_t Sha256Class::write ( uint8_t  data )

virtual

Adds data to the buffer. Also increases the byteCount variable

size_t Sha256Class::write_L

(

const char *

str

)

Adds the str to the buffer Calles function in order to add the data into the buffer.

Parameters

str	The string to be added

Note

Print class does not exist in linux, so we define it here using

#if defined(SHA1_LINUX) 

size_t Sha256Class::write_L	(	const uint8_t *	buffer,
		size_t	size
	)

Adds the string to the buffer Calles function in order to add the data into the buffer.

Parameters

*buffer	The string to be added
*size	The size of the string

Note

Print class does not exist in linux, so we define it here using

#if defined(SHA1_LINUX) 

size_t Sha256Class::print

(

const char *

str

)

Adds the str to the buffer Calles functions in order to add the data into the buffer.

Parameters

str	The string to be added

Note

Print class does not exist in linux, so we define it here using

#if defined(SHA1_LINUX) 

double Sha256Class::millis

(

)

used in linux in order to retrieve the time in milliseconds.

Returns

returns the milliseconds in a double format.

virtual size_t Sha256Class::write ( uint8_t  )

virtual

Adds data to the buffer. Also increases the byteCount variable

void Sha256Class::pad ( )

private

Implement SHA-1 padding (fips180-2 ยง5.1.1). Pad with 0x80 followed by 0x00 until the end of the block

void Sha256Class::addUncounted ( uint8_t  data )

private

adds the data to the buffer

Parameters

data

void Sha256Class::hashBlock ( )

private

Hash a single block of data

uint32_t Sha256Class::ror32 ( uint32_t  number, uint8_t  bits  )

private

ror32 - rotate a 32-bit value left

Parameters

number	value to rotate
bits	bits to roll

Member Data Documentation

_buffer Sha256Class::buffer

private

hold the buffer for the hashing process

uint8_t Sha256Class::bufferOffset

private

indicates the position on the buffer

_state Sha256Class::state

private

identical structure with buffer

uint32_t Sha256Class::byteCount

private

Byte counter in order to initialize the hash process for a block

uint8_t Sha256Class::keyBuffer[BLOCK_LENGTH]

private

Hold the key for the HMAC process

uint8_t Sha256Class::innerHash[HASH_LENGTH]

private

holds the inner hash for the HMAC process

timeval Sha256Class::tv

private

hold the time value on linux machines (ex Raspberry Pi)