sha2_routines.c File Reference

Software implementation of the SHA256 algorithm.

Copyright

(c) 2019 Microchip Technology Inc. and its subsidiaries.

#include <string.h>
#include "sha2_routines.h"

Macros
#define	rotate_right(value, places)   ((value >> places) | (value << (32 - places)))

Functions
void	sw_sha256 (const uint8_t *message, unsigned int len, uint8_t digest[SHA256_DIGEST_SIZE])
	single call convenience function which computes Hash of given data using SHA256 software More...
void	sw_sha256_final (sw_sha256_ctx *ctx, uint8_t digest[SHA256_DIGEST_SIZE])
	completes the final SHA256 calculation and returns the final digest/hash More...
void	sw_sha256_init (sw_sha256_ctx *ctx)
	Intialize the software SHA256. More...
static void	sw_sha256_process (sw_sha256_ctx *ctx, const uint8_t *blocks, uint32_t block_count)
	Processes whole blocks (64 bytes) of data. More...
void	sw_sha256_update (sw_sha256_ctx *ctx, const uint8_t *msg, uint32_t msg_size)
	updates the running hash with the next block of data, called iteratively for the entire stream of data to be hashed using the SHA256 software More...

#define rotate_right	(		value,
			places
	)		((value >> places) | (value << (32 - places)))

Referenced by sw_sha256_process().

void sw_sha256	(	const uint8_t *	message,
		unsigned int	len,
		uint8_t	digest[SHA256_DIGEST_SIZE]
	)

single call convenience function which computes Hash of given data using SHA256 software

Parameters

[in]	message	pointer to stream of data to hash
[in]	len	size of data stream to hash
[out]	digest	result

References sw_sha256_final(), sw_sha256_init(), and sw_sha256_update().

void sw_sha256_final	(	sw_sha256_ctx *	ctx,
		uint8_t	digest[SHA256_DIGEST_SIZE]
	)

completes the final SHA256 calculation and returns the final digest/hash

Parameters

[in]	ctx	ptr to context data structure
[out]	digest	receives the computed digest of the SHA 256

References sw_sha256_ctx::block, sw_sha256_ctx::block_size, sw_sha256_ctx::hash, i, j, SHA256_BLOCK_SIZE, sw_sha256_process(), and sw_sha256_ctx::total_msg_size.

Referenced by atcac_sw_sha2_256_finish(), and sw_sha256().

void sw_sha256_init

(

sw_sha256_ctx *

ctx

)

Intialize the software SHA256.

Parameters

[in]

ctx

SHA256 hash context

References sw_sha256_ctx::hash, and i.

Referenced by atcac_sw_sha2_256_init(), and sw_sha256().

static void sw_sha256_process ( sw_sha256_ctx *  ctx, const uint8_t *  blocks, uint32_t  block_count  )

static

Processes whole blocks (64 bytes) of data.

Parameters

[in]	ctx	SHA256 hash context
[in]	blocks	Raw blocks to be processed
[in]	block_count	Number of 64-byte blocks to process

References sw_sha256_ctx::hash, i, rotate_right, and SHA256_BLOCK_SIZE.

Referenced by sw_sha256_final(), and sw_sha256_update().

void sw_sha256_update	(	sw_sha256_ctx *	ctx,
		const uint8_t *	msg,
		uint32_t	msg_size
	)

updates the running hash with the next block of data, called iteratively for the entire stream of data to be hashed using the SHA256 software

Parameters

[in]	ctx	SHA256 hash context
[in]	msg	Raw blocks to be processed
[in]	msg_size	The size of the message passed

References sw_sha256_ctx::block, sw_sha256_ctx::block_size, SHA256_BLOCK_SIZE, sw_sha256_process(), and sw_sha256_ctx::total_msg_size.

Referenced by atcac_sw_sha2_256_update(), and sw_sha256().