1 // GoGOST -- Pure Go GOST cryptographic functions library
2 // Copyright (C) 2015-2019 Sergey Matveev <stargrave@stargrave.org>
4 // This program is free software: you can redistribute it and/or modify
5 // it under the terms of the GNU General Public License as published by
6 // the Free Software Foundation, version 3 of the License.
8 // This program is distributed in the hope that it will be useful,
9 // but WITHOUT ANY WARRANTY; without even the implied warranty of
10 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11 // GNU General Public License for more details.
13 // You should have received a copy of the GNU General Public License
14 // along with this program. If not, see <http://www.gnu.org/licenses/>.
22 "go.cypherpunks.ru/gogost/v4/gost28147"
23 "go.cypherpunks.ru/gogost/v4/gost341194"
26 // RFC 4357 VKO GOST R 34.10-2001 key agreement function.
27 // UKM is user keying material, also called VKO-factor.
28 func (prv *PrivateKey) KEK2001(pub *PublicKey, ukm *big.Int) ([]byte, error) {
29 if prv.Mode != Mode2001 {
30 return nil, errors.New("KEK2001 can not be used in Mode2012")
32 key, err := prv.KEK(pub, ukm)
36 h := gost341194.New(&gost28147.SboxIdGostR341194CryptoProParamSet)
38 return h.Sum(key[:0]), nil