include/apr_siphash.h File Reference

APR-UTIL siphash library "SipHash-c-d is a family of pseudorandom functions (a.k.a. keyed hash functions) optimized for speed on short messages", designed by Jean-Philippe Aumasson and Daniel J. Bernstein. It generates a 64bit hash (or MAC) from the message and a 128bit key. See http://cr.yp.to/siphash/siphash-20120620.pdf for the details, c is the number of compression rounds, d the number of finalization rounds; we also define fast implementations for c = 2 with d = 4 (aka siphash-2-4), and c = 4 with d = 8 (aka siphash-4-8), as recommended parameters per the authors. More...

#include "apr.h"

Go to the source code of this file.

Defines
#define	APR_SIPHASH_DSIZE   8
#define	APR_SIPHASH_KSIZE   16
Functions
	APR_DECLARE (apr_uint64_t) apr_siphash(const void *src
	Computes SipHash-c-d, producing a 64bit (APR_SIPHASH_DSIZE) hash from a message and a 128bit (APR_SIPHASH_KSIZE) secret key.
	APR_DECLARE (void) apr_siphash_auth(unsigned char out[APR_SIPHASH_DSIZE]
	Computes SipHash-c-d, producing a 64bit (APR_SIPHASH_DSIZE) hash from a message and a 128bit (APR_SIPHASH_KSIZE) secret key, into a possibly unaligned buffer (using the little endian representation as defined by the authors for interoperabilty) usable as a MAC.
Variables
apr_size_t	len
apr_size_t const unsigned char	key [APR_SIPHASH_KSIZE]
apr_size_t const unsigned char unsigned int	c
apr_size_t const unsigned char unsigned int unsigned int	d
const void *	src

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Detailed Description

APR-UTIL siphash library "SipHash-c-d is a family of pseudorandom functions (a.k.a. keyed hash functions) optimized for speed on short messages", designed by Jean-Philippe Aumasson and Daniel J. Bernstein. It generates a 64bit hash (or MAC) from the message and a 128bit key. See http://cr.yp.to/siphash/siphash-20120620.pdf for the details, c is the number of compression rounds, d the number of finalization rounds; we also define fast implementations for c = 2 with d = 4 (aka siphash-2-4), and c = 4 with d = 8 (aka siphash-4-8), as recommended parameters per the authors.

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Define Documentation

#define APR_SIPHASH_DSIZE   8

size of the siphash digest

#define APR_SIPHASH_KSIZE   16

size of the siphash key

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Function Documentation

APR_DECLARE

(

void

)

Computes SipHash-c-d, producing a 64bit (APR_SIPHASH_DSIZE) hash from a message and a 128bit (APR_SIPHASH_KSIZE) secret key, into a possibly unaligned buffer (using the little endian representation as defined by the authors for interoperabilty) usable as a MAC.

Computes SipHash-4-8, producing a 64bit (APR_SIPHASH_DSIZE) hash from a message and a 128bit (APR_SIPHASH_KSIZE) secret key, into a possibly unaligned buffer (using the little endian representation as defined by the authors for interoperabilty) usable as a MAC.

Computes SipHash-2-4, producing a 64bit (APR_SIPHASH_DSIZE) hash from a message and a 128bit (APR_SIPHASH_KSIZE) secret key, into a possibly unaligned buffer (using the little endian representation as defined by the authors for interoperabilty) usable as a MAC.

Parameters:

	out	The output buffer (or MAC)
	src	The message
	len	The length of the message
	key	The secret key
	c	The number of compression rounds
	d	The number of finalization rounds

Returns:

The hash value as a 64bit unsigned integer

Parameters:

	out	The output buffer (or MAC)
	src	The message
	len	The length of the message
	key	The secret key

Returns:

The hash value as a 64bit unsigned integer

APR_DECLARE

(

apr_uint64_t

)

const

Computes SipHash-c-d, producing a 64bit (APR_SIPHASH_DSIZE) hash from a message and a 128bit (APR_SIPHASH_KSIZE) secret key.

Computes SipHash-4-8, producing a 64bit (APR_SIPHASH_DSIZE) hash from a message and a 128bit (APR_SIPHASH_KSIZE) secret key.

Computes SipHash-2-4, producing a 64bit (APR_SIPHASH_DSIZE) hash from a message and a 128bit (APR_SIPHASH_KSIZE) secret key.

Parameters:

	src	The message
	len	The length of the message
	key	The secret key
	c	The number of compression rounds
	d	The number of finalization rounds

Returns:

The hash value as a 64bit unsigned integer

Parameters:

	src	The message to hash
	len	The length of the message
	key	The secret key

Returns:

The hash value as a 64bit unsigned integer

Parameters:

	src	The message
	len	The length of the message
	key	The secret key

Returns:

The hash value as a 64bit unsigned integer