vli.h File Reference

Definition of Large Integer math. More...

#include <stdint.h>
#include "epid/common/bitsupplier.h"

Functions
uint32_t	VliAdd (VeryLargeInt *result, VeryLargeInt const *left, VeryLargeInt const *right)
	Add two large integers. More...
void	VliMul (VeryLargeIntProduct *result, VeryLargeInt const *left, VeryLargeInt const *right)
	Multiply two large integers. More...
void	VliRShift (VeryLargeInt *result, VeryLargeInt const *in, uint32_t shift)
	Right shift a large integers. More...
uint32_t	VliSub (VeryLargeInt *result, VeryLargeInt const *left, VeryLargeInt const *right)
	Subtract two large integers. More...
void	VliSet (VeryLargeInt *result, VeryLargeInt const *in)
	Set a large integer's value. More...
void	VliClear (VeryLargeInt *result)
	Clear a large integer's value. More...
int	VliIsZero (VeryLargeInt const *in)
	Test if a large integer is zero. More...
void	VliCondSet (VeryLargeInt *result, VeryLargeInt const *true_val, VeryLargeInt const *false_val, int truth_val)
	Conditionally Set a large inter's value to one of two values. More...
uint32_t	VliTestBit (VeryLargeInt const *in, uint32_t bit)
	Test the value of a bit in a large integer. More...
int	VliRand (VeryLargeInt *result, BitSupplier rnd_func, void *rnd_param)
	Generate a random large integer. More...
int	VliCmp (VeryLargeInt const *left, VeryLargeInt const *right)
	compare two large integers. More...
void	VliModAdd (VeryLargeInt *result, VeryLargeInt const *left, VeryLargeInt const *right, VeryLargeInt const *mod)
	Add two large integers modulo a value. More...
void	VliModSub (VeryLargeInt *result, VeryLargeInt const *left, VeryLargeInt const *right, VeryLargeInt const *mod)
	Subtract two large integers modulo a value. More...
void	VliModMul (VeryLargeInt *result, VeryLargeInt const *left, VeryLargeInt const *right, VeryLargeInt const *mod)
	Multiply two large integers modulo a value. More...
void	VliModExp (VeryLargeInt *result, VeryLargeInt const *base, VeryLargeInt const *exp, VeryLargeInt const *mod)
	Exponentiate a large integer modulo a value. More...
void	VliModInv (VeryLargeInt *result, VeryLargeInt const *input, VeryLargeInt const *mod)
	Invert a large integer modulo a value. More...
void	VliModSquare (VeryLargeInt *result, VeryLargeInt const *input, VeryLargeInt const *mod)
	Square a large integer modulo a value. More...
void	VliModBarrett (VeryLargeInt *result, VeryLargeIntProduct const *input, VeryLargeInt const *mod)
	Reduce a value to a modulo. More...

Detailed Description

Definition of Large Integer math.

Function Documentation

VliAdd()

uint32_t VliAdd	(	VeryLargeInt *	result,
		VeryLargeInt const *	left,
		VeryLargeInt const *	right
	)

Add two large integers.

Parameters

[out]	result	target.
[in]	left	The first operand to be added.
[in]	right	The second operand to be added.

Returns

the carry portion of the addition.

VliClear()

void VliClear

(

VeryLargeInt *

result

)

Clear a large integer's value.

Parameters

[out]

result

value to clear.

VliCmp()

int VliCmp	(	VeryLargeInt const *	left,
		VeryLargeInt const *	right
	)

compare two large integers.

Parameters

[in]	left	the left hand value.
[in]	right	the right hand value.

Returns

the sign of left - right

VliCondSet()

void VliCondSet	(	VeryLargeInt *	result,
		VeryLargeInt const *	true_val,
		VeryLargeInt const *	false_val,
		int	truth_val
	)

Conditionally Set a large inter's value to one of two values.

Parameters

[out]	result	target.
[in]	true_val	value to set if condition is true.
[in]	false_val	value to set if condition is false.
[in]	truth_val	value of condition.

VliIsZero()

int VliIsZero

(

VeryLargeInt const *

in

)

Test if a large integer is zero.

Parameters

[in]

in

the value to test.

Returns

A value different from zero (i.e., true) if indeed the value is zero. Zero (i.e., false) otherwise.

VliModAdd()

void VliModAdd	(	VeryLargeInt *	result,
		VeryLargeInt const *	left,
		VeryLargeInt const *	right,
		VeryLargeInt const *	mod
	)

Add two large integers modulo a value.

Parameters

[out]	result	target.
[in]	left	The first operand to be added.
[in]	right	The second operand to be added.
[in]	mod	The modulo.

VliModBarrett()

void VliModBarrett	(	VeryLargeInt *	result,
		VeryLargeIntProduct const *	input,
		VeryLargeInt const *	mod
	)

Reduce a value to a modulo.

Parameters

[out]	result	target.
[in]	input	the base.
[in]	mod	The modulo.

Warning

This function makes significant assumptions about the range of values input

VliModExp()

void VliModExp	(	VeryLargeInt *	result,
		VeryLargeInt const *	base,
		VeryLargeInt const *	exp,
		VeryLargeInt const *	mod
	)

Exponentiate a large integer modulo a value.

Parameters

[out]	result	target.
[in]	base	the base.
[in]	exp	the exponent.
[in]	mod	The modulo.

VliModInv()

void VliModInv	(	VeryLargeInt *	result,
		VeryLargeInt const *	input,
		VeryLargeInt const *	mod
	)

Invert a large integer modulo a value.

Parameters

[out]	result	target.
[in]	input	the value to invert.
[in]	mod	The modulo.

VliModMul()

void VliModMul	(	VeryLargeInt *	result,
		VeryLargeInt const *	left,
		VeryLargeInt const *	right,
		VeryLargeInt const *	mod
	)

Multiply two large integers modulo a value.

Parameters

[out]	result	target.
[in]	left	The first operand to be multiplied.
[in]	right	The second operand to be multiplied.
[in]	mod	The modulo.

VliModSquare()

void VliModSquare	(	VeryLargeInt *	result,
		VeryLargeInt const *	input,
		VeryLargeInt const *	mod
	)

Square a large integer modulo a value.

Parameters

[out]	result	target.
[in]	input	the base.
[in]	mod	The modulo.

VliModSub()

void VliModSub	(	VeryLargeInt *	result,
		VeryLargeInt const *	left,
		VeryLargeInt const *	right,
		VeryLargeInt const *	mod
	)

Subtract two large integers modulo a value.

Parameters

[out]	result	target.
[in]	left	The operand to be subtracted from.
[in]	right	The operand to subtract.
[in]	mod	The modulo.

VliMul()

void VliMul	(	VeryLargeIntProduct *	result,
		VeryLargeInt const *	left,
		VeryLargeInt const *	right
	)

Multiply two large integers.

Parameters

[out]	result	of multiplying left and right.
[in]	left	The first operand to be multiplied.
[in]	right	The second operand to be multiplied.

VliRand()

int VliRand	(	VeryLargeInt *	result,
		BitSupplier	rnd_func,
		void *	rnd_param
	)

Generate a random large integer.

Parameters

[in]	result	the random value.
[in]	rnd_func	Random number generator.
[in]	rnd_param	Pass through context data for rnd_func.

Returns

A value different from zero (i.e., true) if on success. Zero (i.e., false) otherwise.

VliRShift()

void VliRShift	(	VeryLargeInt *	result,
		VeryLargeInt const *	in,
		uint32_t	shift
	)

Right shift a large integers.

Parameters

[out]	result	target.
[in]	in	The value to be shifted.
[in]	shift	The number of bits to shift.

VliSet()

void VliSet	(	VeryLargeInt *	result,
		VeryLargeInt const *	in
	)

Set a large integer's value.

Parameters

[out]	result	target.
[in]	in	value to set.

VliSub()

uint32_t VliSub	(	VeryLargeInt *	result,
		VeryLargeInt const *	left,
		VeryLargeInt const *	right
	)

Subtract two large integers.

Parameters

[out]	result	target.
[in]	left	The operand to be subtracted from.
[in]	right	The operand to subtract.

Returns

1 on success, 0 on failure

VliTestBit()

uint32_t VliTestBit	(	VeryLargeInt const *	in,
		uint32_t	bit
	)

Test the value of a bit in a large integer.

Parameters

[in]	in	the value to test.
[in]	bit	the bit index.

Returns

value of the bit (1 or 0).