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 func (prv *PrivateKey) KEK(pub *PublicKey, ukm *big.Int) ([]byte, error) {
23 keyX, keyY, err := prv.C.Exp(prv.Key, pub.X, pub.Y)
27 if ukm.Cmp(bigInt1) != 0 {
28 keyX, keyY, err = prv.C.Exp(ukm, keyX, keyY)
33 pk := PublicKey{prv.C, prv.Mode, keyX, keyY}