X-Git-Url: http://www.git.cypherpunks.ru/?a=blobdiff_plain;f=gost3410%2Fvko.go;h=b3036f577d2c7bd26a03ff38bdaa4442450ca3cb;hb=6d9056bfe4a2d69469a1e70f3bf08f89b377b06e;hp=bb10f9430b98bbf818c24e2bbb912bafb8fffa6e;hpb=c07494bbd559b9d00f391e28cfd070e18afe9900;p=gogost.git

diff --git a/gost3410/vko.go b/gost3410/vko.go
index bb10f94..b3036f5 100644
--- a/gost3410/vko.go
+++ b/gost3410/vko.go
@@ -1,5 +1,5 @@
 // GoGOST -- Pure Go GOST cryptographic functions library
-// Copyright (C) 2015-2019 Sergey Matveev <stargrave@stargrave.org>
+// Copyright (C) 2015-2021 Sergey Matveev <stargrave@stargrave.org>
 //
 // 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
@@ -24,12 +24,13 @@ func (prv *PrivateKey) KEK(pub *PublicKey, ukm *big.Int) ([]byte, error) {
 	if err != nil {
 		return nil, err
 	}
-	if ukm.Cmp(bigInt1) != 0 {
-		keyX, keyY, err = prv.C.Exp(ukm, keyX, keyY)
+	u := big.NewInt(0).Set(ukm).Mul(ukm, prv.C.Co)
+	if u.Cmp(bigInt1) != 0 {
+		keyX, keyY, err = prv.C.Exp(u, keyX, keyY)
 		if err != nil {
 			return nil, err
 		}
 	}
-	pk := PublicKey{prv.C, prv.Mode, keyX, keyY}
+	pk := PublicKey{prv.C, keyX, keyY}
 	return pk.Raw(), nil
 }