Curve25519 elliptic curve (constant-time implementation) More...

#include "core/crypto.h"

Macros
#define	CURVE25519_BIT_LEN 255

#define	CURVE25519_BYTE_LEN 32

#define	CURVE25519_WORD_LEN 8

#define	CURVE25519_A24 121666

Functions
void	curve25519SetInt (uint32_t *a, uint32_t b)
	Set integer value. More...

void	curve25519Add (uint32_t r, const uint32_t a, const uint32_t *b)
	Modular addition. More...

void	curve25519AddInt (uint32_t r, const uint32_t a, uint32_t b)
	Modular addition. More...

void	curve25519Sub (uint32_t r, const uint32_t a, const uint32_t *b)
	Modular subtraction. More...

void	curve25519SubInt (uint32_t r, const uint32_t a, uint32_t b)
	Modular subtraction. More...

void	curve25519Mul (uint32_t r, const uint32_t a, const uint32_t *b)
	Modular multiplication. More...

void	curve25519MulInt (uint32_t r, const uint32_t a, uint32_t b)
	Modular multiplication. More...

void	curve25519Red (uint32_t r, const uint32_t a)
	Modular reduction. More...

void	curve25519Sqr (uint32_t r, const uint32_t a)
	Modular squaring. More...

void	curve25519Pwr2 (uint32_t r, const uint32_t a, uint_t n)
	Raise an integer to power 2^n. More...

void	curve25519Inv (uint32_t r, const uint32_t a)
	Modular multiplicative inverse. More...

uint32_t	curve25519Sqrt (uint32_t r, const uint32_t a, const uint32_t *b)
	Compute the square root of (A / B) modulo p. More...

void	curve25519Copy (uint32_t a, const uint32_t b)
	Copy an integer. More...

void	curve25519Swap (uint32_t a, uint32_t b, uint32_t c)
	Conditional swap. More...

void	curve25519Select (uint32_t r, const uint32_t a, const uint32_t *b, uint32_t c)
	Select an integer. More...

uint32_t	curve25519Comp (const uint32_t a, const uint32_t b)
	Compare integers. More...

void	curve25519Import (uint32_t a, const uint8_t data)
	Import an octet string. More...

void	curve25519Export (uint32_t a, uint8_t data)
	Export an octet string. More...

Detailed Description

Curve25519 elliptic curve (constant-time implementation)

License

SPDX-License-Identifier: GPL-2.0-or-later

This file is part of CycloneCRYPTO Open.

This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.

Author: Oryx Embedded SARL (www.oryx-embedded.com)

Version: 2.4.4

Definition in file curve25519.h.

Macro Definition Documentation

◆ CURVE25519_A24

#define CURVE25519_A24 121666

Definition at line 43 of file curve25519.h.

◆ CURVE25519_BIT_LEN

#define CURVE25519_BIT_LEN 255

Definition at line 38 of file curve25519.h.

◆ CURVE25519_BYTE_LEN

#define CURVE25519_BYTE_LEN 32

Definition at line 39 of file curve25519.h.

◆ CURVE25519_WORD_LEN

#define CURVE25519_WORD_LEN 8

Definition at line 40 of file curve25519.h.

Function Documentation

◆ curve25519Add()

void curve25519Add	(	uint32_t *	r,
		const uint32_t *	a,
		const uint32_t *	b
	)

Modular addition.

Parameters

[out]	r	Resulting integer R = (A + B) mod p
[in]	a	An integer such as 0 <= A < p
[in]	b	An integer such as 0 <= B < p

Definition at line 79 of file curve25519.c.

◆ curve25519AddInt()

void curve25519AddInt	(	uint32_t *	r,
		const uint32_t *	a,
		uint32_t	b
	)

Modular addition.

Parameters

[out]	r	Resulting integer R = (A + B) mod p
[in]	a	An integer such as 0 <= A < p
[in]	b	An integer such as 0 <= B < (2^32 - 1)

Definition at line 105 of file curve25519.c.

◆ curve25519Comp()

uint32_t curve25519Comp	(	const uint32_t *	a,
		const uint32_t *	b
	)

Compare integers.

Parameters

[in]	a	Pointer to the first integer
[in]	b	Pointer to the second integer

Returns: The function returns 0 if the A = B, else 1

Definition at line 587 of file curve25519.c.

◆ curve25519Copy()

void curve25519Copy	(	uint32_t *	a,
		const uint32_t *	b
	)

Copy an integer.

Parameters

[out]	a	Pointer to the destination integer
[in]	b	Pointer to the source integer

Definition at line 515 of file curve25519.c.

◆ curve25519Export()

void curve25519Export	(	uint32_t *	a,
		uint8_t *	data
	)

Export an octet string.

Parameters

[in]	a	Pointer to the integer to be exported
[out]	data	Octet string resulting from the conversion

Definition at line 634 of file curve25519.c.

◆ curve25519Import()

void curve25519Import	(	uint32_t *	a,
		const uint8_t *	data
	)

Import an octet string.

Parameters

[out]	a	Pointer to resulting integer
[in]	data	Octet string to be converted

Definition at line 613 of file curve25519.c.

◆ curve25519Inv()

void curve25519Inv	(	uint32_t *	r,
		const uint32_t *	a
	)

Modular multiplicative inverse.

Parameters

[out]	r	Resulting integer R = A^-1 mod p
[in]	a	An integer such as 0 <= A < p

Definition at line 380 of file curve25519.c.

◆ curve25519Mul()

void curve25519Mul	(	uint32_t *	r,
		const uint32_t *	a,
		const uint32_t *	b
	)

Modular multiplication.

Parameters

[out]	r	Resulting integer R = (A * B) mod p
[in]	a	An integer such as 0 <= A < p
[in]	b	An integer such as 0 <= B < p

Definition at line 191 of file curve25519.c.

◆ curve25519MulInt()

void curve25519MulInt	(	uint32_t *	r,
		const uint32_t *	a,
		uint32_t	b
	)

Modular multiplication.

Parameters

[out]	r	Resulting integer R = (A * B) mod p
[in]	a	An integer such as 0 <= A < p
[in]	b	An integer such as 0 <= B < (2^32 - 1)

Definition at line 277 of file curve25519.c.

◆ curve25519Pwr2()

void curve25519Pwr2	(	uint32_t *	r,
		const uint32_t *	a,
		uint_t	n
	)

Raise an integer to power 2^n.

Parameters

[out]	r	Resulting integer R = (A ^ (2^n)) mod p
[in]	a	An integer such as 0 <= A < p
[in]	n	An integer such as n >= 1

Definition at line 331 of file curve25519.c.

◆ curve25519Red()

void curve25519Red	(	uint32_t *	r,
		const uint32_t *	a
	)

Modular reduction.

Parameters

[out]	r	Resulting integer R = A mod p
[in]	a	An integer such as 0 <= A < (2 * p)

Definition at line 352 of file curve25519.c.

◆ curve25519Select()

void curve25519Select	(	uint32_t *	r,
		const uint32_t *	a,
		const uint32_t *	b,
		uint32_t	c
	)

Select an integer.

Parameters

[out]	r	Pointer to the destination integer
[in]	a	Pointer to the first source integer
[in]	b	Pointer to the second source integer
[in]	c	Condition variable

Definition at line 562 of file curve25519.c.

◆ curve25519SetInt()

void curve25519SetInt	(	uint32_t *	a,
		uint32_t	b
	)

Set integer value.

Parameters

[out]	a	Pointer to the integer to be initialized
[in]	b	Initial value

Definition at line 57 of file curve25519.c.

◆ curve25519Sqr()

void curve25519Sqr	(	uint32_t *	r,
		const uint32_t *	a
	)

Modular squaring.

Parameters

[out]	r	Resulting integer R = (A ^ 2) mod p
[in]	a	An integer such as 0 <= A < p

Definition at line 317 of file curve25519.c.

◆ curve25519Sqrt()

uint32_t curve25519Sqrt	(	uint32_t *	r,
		const uint32_t *	a,
		const uint32_t *	b
	)

Compute the square root of (A / B) modulo p.

Parameters

[out]	r	Resulting integer R = (A / B)^(1 / 2) mod p
[in]	a	An integer such as 0 <= A < p
[in]	b	An integer such as 0 < B < p

Returns: The function returns 0 if the square root exists, else 1

Definition at line 430 of file curve25519.c.

◆ curve25519Sub()

void curve25519Sub	(	uint32_t *	r,
		const uint32_t *	a,
		const uint32_t *	b
	)

Modular subtraction.

Parameters

[out]	r	Resulting integer R = (A - B) mod p
[in]	a	An integer such as 0 <= A < p
[in]	b	An integer such as 0 <= B < p

Definition at line 130 of file curve25519.c.

◆ curve25519SubInt()

void curve25519SubInt	(	uint32_t *	r,
		const uint32_t *	a,
		uint32_t	b
	)

Modular subtraction.

Parameters

[out]	r	Resulting integer R = (A - B) mod p
[in]	a	An integer such as 0 <= A < p
[in]	b	An integer such as 0 <= B < (2^32 - 1)

Definition at line 159 of file curve25519.c.

◆ curve25519Swap()

void curve25519Swap	(	uint32_t *	a,
		uint32_t *	b,
		uint32_t	c
	)

Conditional swap.

Parameters

[in,out]	a	Pointer to the first integer
[in,out]	b	Pointer to the second integer
[in]	c	Condition variable

Definition at line 534 of file curve25519.c.

Macros

Functions

Detailed Description

License

Macro Definition Documentation

◆ CURVE25519_A24

◆ CURVE25519_BIT_LEN

◆ CURVE25519_BYTE_LEN

◆ CURVE25519_WORD_LEN

Function Documentation

◆ curve25519Add()

◆ curve25519AddInt()

◆ curve25519Comp()

◆ curve25519Copy()

◆ curve25519Export()

◆ curve25519Import()

◆ curve25519Inv()

◆ curve25519Mul()

◆ curve25519MulInt()

◆ curve25519Pwr2()

◆ curve25519Red()

◆ curve25519Select()

◆ curve25519SetInt()

◆ curve25519Sqr()

◆ curve25519Sqrt()

◆ curve25519Sub()

◆ curve25519SubInt()

◆ curve25519Swap()