ge25519

Documentation

Overview

Package ge25519 implements arithmetic on the twisted Edwards curve -x^2 + y^2 = 1 + dx^2y^2 with d = -(121665/121666) = 37095705934669439343138083508754565189542113879843219016388785533085940283555

Base point: (15112221349535400772501151409588531511454012693041857206046113283949847762202,46316835694926478169428394003475163141307993866256225615783033603165251855960);

Index

• Variables
• func Add(r, p, q *Ge25519)
• func CofactorEqual(p, q *Ge25519) bool
• func CofactorMultiply(r, p *Ge25519)
• func Double(r *Ge25519, p *Ge25519)
• func DoubleScalarmultVartime(r, p1 *Ge25519, s1, s2 *modm.Bignum256)
• func IsNeutralVartime(q *Ge25519) bool
• func Pack(r []byte, p *Ge25519)
• func ProjectiveToExtended(r, p *Ge25519)
• func ScalarmultBaseNiels(r *Ge25519, basepointTable *[256][96]byte, s *modm.Bignum256)
• func UnpackNegativeVartime(r *Ge25519, p []byte) bool
• func UnpackVartime(r *Ge25519, p []byte) bool
• type Ge25519
  • func (r *Ge25519) Reset()
  • func (r *Ge25519) X() *curve25519.Bignum25519
  • func (r *Ge25519) Y() *curve25519.Bignum25519
  • func (r *Ge25519) Z() *curve25519.Bignum25519

Variables

var Basepoint = Ge25519{
	curve25519.Bignum25519{0x00062d608f25d51a, 0x000412a4b4f6592a, 0x00075b7171a4b31d, 0x0001ff60527118fe, 0x000216936d3cd6e5},
	curve25519.Bignum25519{0x0006666666666658, 0x0004cccccccccccc, 0x0001999999999999, 0x0003333333333333, 0x0006666666666666},
	curve25519.Bignum25519{0x0000000000000001, 0x0000000000000000, 0x0000000000000000, 0x0000000000000000, 0x0000000000000000},
	curve25519.Bignum25519{0x00068ab3a5b7dda3, 0x00000eea2a5eadbb, 0x0002af8df483c27e, 0x000332b375274732, 0x00067875f0fd78b7},
}

ge25519_basepoint

var NielsBaseMultiples = [256][96]byte{}/* 256 elements not displayed */

multiples of the base point in packed {ysubx, xaddy, t2d} form

Functions

func Add

func Add(r, p, q *Ge25519)

func CofactorEqual

func CofactorEqual(p, q *Ge25519) bool

CofactorEqual checks whether p, q are equal up to cofactor multiplication (ie. if their difference is of small order).

func CofactorMultiply

func CofactorMultiply(r, p *Ge25519)

CofactorMultiply multiplies the full group element by the cofactor (8).

func Double

func Double(r *Ge25519, p *Ge25519)

func DoubleScalarmultVartime

func DoubleScalarmultVartime(r, p1 *Ge25519, s1, s2 *modm.Bignum256)

computes [s1]p1 + [s2]basepoint

func IsNeutralVartime

func IsNeutralVartime(q *Ge25519) bool

IsNeutralVartime returns true iff the q is the identity point.

func Pack

func Pack(r []byte, p *Ge25519)

func ProjectiveToExtended

func ProjectiveToExtended(r, p *Ge25519)

ProjectiveToExtended converts p from a projective group element to an extended group element.

func ScalarmultBaseNiels

func ScalarmultBaseNiels(r *Ge25519, basepointTable *[256][96]byte, s *modm.Bignum256)

computes [s]basepoint

func UnpackNegativeVartime

func UnpackNegativeVartime(r *Ge25519, p []byte) bool

func UnpackVartime

func UnpackVartime(r *Ge25519, p []byte) bool

Types

type Ge25519

type Ge25519 struct {
	// contains filtered or unexported fields
}

func (*Ge25519) Reset

func (r *Ge25519) Reset()

func (*Ge25519) X

func (r *Ge25519) X() *curve25519.Bignum25519

func (*Ge25519) Y

func (r *Ge25519) Y() *curve25519.Bignum25519

func (*Ge25519) Z

func (r *Ge25519) Z() *curve25519.Bignum25519