gost3410.Public/Private keys BE/LE marshalling

[gogost.git] / gost3410 / public.go

diff --git a/gost3410/public.go b/gost3410/public.go
index d2c01bc67acbd2990378f3bd3d1e578617a05e2b..ef5926bc336a03705ef44eaceb00f4656cc574bb 100644 (file)
--- a/gost3410/public.go
+++ b/gost3410/public.go
@@ -23,12 +23,11 @@ import (
 
 type PublicKey struct {
        C *Curve
-       X *big.Int
-       Y *big.Int
+       X, Y *big.Int
 }
 
 // Unmarshal LE(X)||LE(Y) public key. "raw" must be 2*c.PointSize() length.
-func NewPublicKey(c *Curve, raw []byte) (*PublicKey, error) {
+func NewPublicKeyLE(c *Curve, raw []byte) (*PublicKey, error) {
        pointSize := c.PointSize()
        key := make([]byte, 2*pointSize)
        if len(raw) != len(key) {
@@ -44,10 +43,28 @@ func NewPublicKey(c *Curve, raw []byte) (*PublicKey, error) {
        }, nil
 }
 
+// Unmarshal BE(X)||BE(Y) public key. "raw" must be 2*c.PointSize() length.
+func NewPublicKeyBE(c *Curve, raw []byte) (*PublicKey, error) {
+       pointSize := c.PointSize()
+       if len(raw) != 2*pointSize {
+               return nil, fmt.Errorf("gogost/gost3410: len(key) != %d", 2*pointSize)
+       }
+       return &PublicKey{
+               c,
+               bytes2big(raw[:pointSize]),
+               bytes2big(raw[pointSize:]),
+       }, nil
+}
+
+// This is an alias for NewPublicKeyLE().
+func NewPublicKey(c *Curve, raw []byte) (*PublicKey, error) {
+       return NewPublicKeyLE(c, raw)
+}
+
 // Marshal LE(X)||LE(Y) public key. raw will be 2*pub.C.PointSize() length.
-func (pub *PublicKey) Raw() (raw []byte) {
+func (pub *PublicKey) RawLE() []byte {
        pointSize := pub.C.PointSize()
-       raw = append(
+       raw := append(
                pad(pub.Y.Bytes(), pointSize),
                pad(pub.X.Bytes(), pointSize)...,
        )
@@ -55,6 +72,20 @@ func (pub *PublicKey) Raw() (raw []byte) {
        return raw
 }
 
+// Marshal BE(X)||BE(Y) public key. raw will be 2*pub.C.PointSize() length.
+func (pub *PublicKey) RawBE() []byte {
+       pointSize := pub.C.PointSize()
+       return append(
+               pad(pub.X.Bytes(), pointSize),
+               pad(pub.Y.Bytes(), pointSize)...,
+       )
+}
+
+// This is an alias for RawLE().
+func (pub *PublicKey) Raw() []byte {
+       return pub.RawLE()
+}
+
 func (pub *PublicKey) VerifyDigest(digest, signature []byte) (bool, error) {
        pointSize := pub.C.PointSize()
        if len(signature) != 2*pointSize {