X-Git-Url: http://www.git.cypherpunks.ru/?a=blobdiff_plain;f=gost3410%2Fcurve.go;h=a3685ce047e7be3b7c11ea58f649c09761255d46;hb=4581b7b9da29fc47d4831c1c4b98af2afa40a3cf;hp=696beabed9a68889675f9b96237a924fff30ea91;hpb=4f46a270096b061794b63d7c418cb6ee56af8879;p=gogost.git

diff --git a/gost3410/curve.go b/gost3410/curve.go
index 696beab..a3685ce 100644
--- a/gost3410/curve.go
+++ b/gost3410/curve.go
@@ -25,6 +25,7 @@ var (
 	bigInt1 *big.Int = big.NewInt(1)
 	bigInt2 *big.Int = big.NewInt(2)
 	bigInt3 *big.Int = big.NewInt(3)
+	bigInt4 *big.Int = big.NewInt(4)
 )
 
 type Curve struct {
@@ -33,6 +34,8 @@ type Curve struct {
 	P *big.Int // Characteristic of the underlying prime field
 	Q *big.Int // Elliptic curve subgroup order
 
+	Co *big.Int // Cofactor
+
 	// Equation coefficients of the elliptic curve in canonical form
 	A *big.Int
 	B *big.Int
@@ -55,7 +58,7 @@ type Curve struct {
 	edT *big.Int
 }
 
-func NewCurve(p, q, a, b, x, y, e, d *big.Int) (*Curve, error) {
+func NewCurve(p, q, a, b, x, y, e, d, co *big.Int) (*Curve, error) {
 	c := Curve{
 		Name: "unknown",
 		P:    p,
@@ -85,6 +88,11 @@ func NewCurve(p, q, a, b, x, y, e, d *big.Int) (*Curve, error) {
 		c.E = e
 		c.D = d
 	}
+	if co == nil {
+		c.Co = bigInt1
+	} else {
+		c.Co = co
+	}
 	return &c, nil
 }