sm2

Documentation

Overview

Package elliptic implements several standard elliptic curves over prime fields.

Package sm2 implements china crypto standards.

Index

• Variables
• func AffineToP256Point(x, y *big.Int) (out p256Point)
• func Decrypt(c []byte, key *PrivateKey) ([]byte, error)
• func Encrypt(rand io.Reader, key *PublicKey, msg []byte) (cipher []byte, err error)
• func Hexprint(in []byte)
• func Marshal(curve Curve, x, y *big.Int) []byte
• func Sign(rand io.Reader, priv *PrivateKey, msg []byte) (r, s *big.Int, err error)
• func SignWithDigest(rand io.Reader, priv *PrivateKey, digest []byte) (r, s *big.Int, err error)
• func Sm2KeyGen(rand io.Reader) (sk, pk []byte, err error)
• func Sm2Sign(sk, pk, msg []byte) ([]byte, error)
• func Sm2Verify(sign, pk, msg []byte) bool
• func Uint64ToAffine(in []uint64) (x, y *big.Int)
• func Unmarshal(curve Curve, data []byte) (x, y *big.Int)
• func Verify(pub *PublicKey, msg []byte, r, s *big.Int) bool
• func VerifyWithDigest(pub *PublicKey, digest []byte, r, s *big.Int) bool
• type Curve
  • func P256() Curve
• type CurveParams
  • func (curve *CurveParams) Add(x1, y1, x2, y2 *big.Int) (*big.Int, *big.Int)
  • func (curve *CurveParams) Double(x1, y1 *big.Int) (*big.Int, *big.Int)
  • func (curve *CurveParams) IsOnCurve(x, y *big.Int) bool
  • func (curve *CurveParams) Params() *CurveParams
  • func (curve *CurveParams) ScalarBaseMult(k []byte) (*big.Int, *big.Int)
  • func (curve *CurveParams) ScalarMult(Bx, By *big.Int, k []byte) (*big.Int, *big.Int)
• type PrivateKey
  • func GenerateKey(rand io.Reader) (*PrivateKey, error)
  • func (priv *PrivateKey) Public() crypto.PublicKey
  • func (priv *PrivateKey) Sign(rand io.Reader, msg []byte) ([]byte, error)
• type PublicKey
  • func (pub *PublicKey) Verify(msg []byte, sign []byte) bool
• type Sm2PrivateKey
• type Sm2PublicKey

Variables

var DecryptionErr = errors.New("sm2: decryption error")

var EncryptionErr = errors.New("sm2: encryption error")

Functions

func AffineToP256Point

func AffineToP256Point(x, y *big.Int) (out p256Point)

func Decrypt

func Decrypt(c []byte, key *PrivateKey) ([]byte, error)

func Encrypt

func Encrypt(rand io.Reader, key *PublicKey, msg []byte) (cipher []byte, err error)

func Hexprint

func Hexprint(in []byte)

func Marshal

func Marshal(curve Curve, x, y *big.Int) []byte

Marshal converts a point into the uncompressed form specified in section 4.3.6 of ANSI X9.62.

func Sign

func Sign(rand io.Reader, priv *PrivateKey, msg []byte) (r, s *big.Int, err error)

func SignWithDigest

func SignWithDigest(rand io.Reader, priv *PrivateKey, digest []byte) (r, s *big.Int, err error)

func Sm2KeyGen

func Sm2KeyGen(rand io.Reader) (sk, pk []byte, err error)

func Sm2Sign

func Sm2Sign(sk, pk, msg []byte) ([]byte, error)

func Sm2Verify

func Sm2Verify(sign, pk, msg []byte) bool

func Uint64ToAffine

func Uint64ToAffine(in []uint64) (x, y *big.Int)

func Unmarshal

func Unmarshal(curve Curve, data []byte) (x, y *big.Int)

Unmarshal converts a point, serialized by Marshal, into an x, y pair. It is an error if the point is not in uncompressed form or is not on the curve. On error, x = nil.

func Verify

func Verify(pub *PublicKey, msg []byte, r, s *big.Int) bool

func VerifyWithDigest

func VerifyWithDigest(pub *PublicKey, digest []byte, r, s *big.Int) bool

Types

type Curve

type Curve interface {
	// Params returns the parameters for the curve.
	Params() *CurveParams
	// IsOnCurve reports whether the given (x,y) lies on the curve.
	IsOnCurve(x, y *big.Int) bool
	// Add returns the sum of (x1,y1) and (x2,y2)
	Add(x1, y1, x2, y2 *big.Int) (x, y *big.Int)
	// Double returns 2*(x,y)
	Double(x1, y1 *big.Int) (x, y *big.Int)
	// ScalarMult returns k*(Bx,By) where k is a number in big-endian form.
	ScalarMult(x1, y1 *big.Int, k []byte) (x, y *big.Int)
	// ScalarBaseMult returns k*G, where G is the base point of the group
	// and k is an integer in big-endian form.
	ScalarBaseMult(k []byte) (x, y *big.Int)
}

A Curve represents a short-form Weierstrass curve with a=-3. See http://www.hyperelliptic.org/EFD/g1p/auto-shortw.html

func P256

func P256() Curve

P256 returns a Curve which implements sm2 curve.

The cryptographic operations are implemented using constant-time algorithms.

type CurveParams

type CurveParams struct {
	P       *big.Int // the order of the underlying field
	N       *big.Int // the order of the base point
	B       *big.Int // the constant of the curve equation
	Gx, Gy  *big.Int // (x,y) of the base point
	BitSize int      // the size of the underlying field
	Name    string   // the canonical name of the curve
}

CurveParams contains the parameters of an elliptic curve and also provides a generic, non-constant time implementation of Curve.

func (*CurveParams) Add

func (curve *CurveParams) Add(x1, y1, x2, y2 *big.Int) (*big.Int, *big.Int)

func (*CurveParams) Double

func (curve *CurveParams) Double(x1, y1 *big.Int) (*big.Int, *big.Int)

func (*CurveParams) IsOnCurve

func (curve *CurveParams) IsOnCurve(x, y *big.Int) bool

func (*CurveParams) Params

func (curve *CurveParams) Params() *CurveParams

func (*CurveParams) ScalarBaseMult

func (curve *CurveParams) ScalarBaseMult(k []byte) (*big.Int, *big.Int)

func (*CurveParams) ScalarMult

func (curve *CurveParams) ScalarMult(Bx, By *big.Int, k []byte) (*big.Int, *big.Int)

type PrivateKey

type PrivateKey struct {
	PublicKey
	D    *big.Int
	DInv *big.Int //(1+d)^-1
}

func GenerateKey

func GenerateKey(rand io.Reader) (*PrivateKey, error)

func (*PrivateKey) Public

func (priv *PrivateKey) Public() crypto.PublicKey

The SM2's private key contains the public key

func (*PrivateKey) Sign

func (priv *PrivateKey) Sign(rand io.Reader, msg []byte) ([]byte, error)

type PublicKey

type PublicKey struct {
	Curve
	X, Y        *big.Int
	PreComputed *[37][64 * 8]uint64 //precomputation
}

func (*PublicKey) Verify

func (pub *PublicKey) Verify(msg []byte, sign []byte) bool

type Sm2PrivateKey

type Sm2PrivateKey struct {
	D *big.Int //sk
}

type Sm2PublicKey

type Sm2PublicKey struct {
	X *big.Int //pk.X
	Y *big.Int //pk.Y
}