sha256.h File Reference

SHA256 hash implementation and interface functions. More...

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Defines
#define	SHA256_MAC_LEN   32
Functions
void	hmac_sha256_vector (const u8 *key, size_t key_len, size_t num_elem, const u8 *addr[], const size_t *len, u8 *mac)
	HMAC-SHA256 over data vector (RFC 2104).
void	hmac_sha256 (const u8 *key, size_t key_len, const u8 *data, size_t data_len, u8 *mac)
	HMAC-SHA256 over data buffer (RFC 2104).
void	sha256_prf (const u8 *key, size_t key_len, const char *label, const u8 *data, size_t data_len, u8 *buf, size_t buf_len)
	SHA256-based Pseudo-Random Function (IEEE 802.11r, 8.5.1.5.2).

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Detailed Description

SHA256 hash implementation and interface functions.

Copyright

Copyright (c) 2003-2006, Jouni Malinen <j@w1.fi>

This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License version 2 as published by the Free Software Foundation.

Alternatively, this software may be distributed under the terms of BSD license.

See README and COPYING for more details.

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Function Documentation

void hmac_sha256	(	const u8 *	key,
		size_t	key_len,
		const u8 *	data,
		size_t	data_len,
		u8 *	mac
	)

HMAC-SHA256 over data buffer (RFC 2104).

Parameters:

	key	Key for HMAC operations
	key_len	Length of the key in bytes
	data	Pointers to the data area
	data_len	Length of the data area
	mac	Buffer for the hash (20 bytes)

void hmac_sha256_vector	(	const u8 *	key,
		size_t	key_len,
		size_t	num_elem,
		const u8 *	addr[],
		const size_t *	len,
		u8 *	mac
	)

HMAC-SHA256 over data vector (RFC 2104).

Parameters:

	key	Key for HMAC operations
	key_len	Length of the key in bytes
	num_elem	Number of elements in the data vector
	addr	Pointers to the data areas
	len	Lengths of the data blocks
	mac	Buffer for the hash (32 bytes)

void sha256_prf	(	const u8 *	key,
		size_t	key_len,
		const char *	label,
		const u8 *	data,
		size_t	data_len,
		u8 *	buf,
		size_t	buf_len
	)

SHA256-based Pseudo-Random Function (IEEE 802.11r, 8.5.1.5.2).

Parameters:

	key	Key for PRF
	key_len	Length of the key in bytes
	label	A unique label for each purpose of the PRF
	data	Extra data to bind into the key
	data_len	Length of the data
	buf	Buffer for the generated pseudo-random key
	buf_len	Number of bytes of key to generate

This function is used to derive new, cryptographically separate keys from a given key.