X-Git-Url: http://www.git.cypherpunks.ru/?a=blobdiff_plain;f=gost3410%2Fvko2001.go;h=0bb8e3d93699546724398eb218214aaf6128ba0a;hb=d681002980ca0b115936a6e217de5649bb8966d3;hp=c9aeada21a90a36f782a49497aaa8c4af347a813;hpb=9f3355e3239fed2b0110b0724e7ba1ed509b8a19;p=gogost.git

diff --git a/gost3410/vko2001.go b/gost3410/vko2001.go
index c9aeada..0bb8e3d 100644
--- a/gost3410/vko2001.go
+++ b/gost3410/vko2001.go
@@ -1,5 +1,5 @@
 // GoGOST -- Pure Go GOST cryptographic functions library
-// Copyright (C) 2015-2020 Sergey Matveev <stargrave@stargrave.org>
+// Copyright (C) 2015-2024 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
@@ -17,25 +17,26 @@ package gost3410
 
 import (
 	"errors"
+	"fmt"
 	"math/big"
 
-	"go.cypherpunks.ru/gogost/v4/gost28147"
-	"go.cypherpunks.ru/gogost/v4/gost341194"
+	"go.cypherpunks.ru/gogost/v5/gost28147"
+	"go.cypherpunks.ru/gogost/v5/gost341194"
 )
 
 // RFC 4357 VKO GOST R 34.10-2001 key agreement function.
 // UKM is user keying material, also called VKO-factor.
 func (prv *PrivateKey) KEK2001(pub *PublicKey, ukm *big.Int) ([]byte, error) {
-	if prv.Mode != Mode2001 {
-		return nil, errors.New("gogost/gost3410: KEK2001 can not be used in Mode2012")
+	if prv.C.PointSize() != 32 {
+		return nil, errors.New("gogost/gost3410: KEK2001 is only for 256-bit curves")
 	}
 	key, err := prv.KEK(pub, ukm)
 	if err != nil {
-		return nil, err
+		return nil, fmt.Errorf("gogost/gost3410.PrivateKey.KEK2001: %w", err)
 	}
 	h := gost341194.New(&gost28147.SboxIdGostR341194CryptoProParamSet)
 	if _, err = h.Write(key); err != nil {
-		return nil, err
+		return nil, fmt.Errorf("gogost/gost3410.PrivateKey.KEK2001: %w", err)
 	}
 	return h.Sum(key[:0]), nil
 }