1 // GoGOST -- Pure Go GOST cryptographic functions library
2 // Copyright (C) 2015-2020 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/>.
18 func (mgm *MGM) mul(xBuf, yBuf []byte) []byte {
23 for mgm.y.BitLen() != 0 {
24 if mgm.y.Bit(0) == 1 {
25 mgm.z.Xor(mgm.z, mgm.x)
27 if mgm.x.Bit(mgm.maxBit) == 1 {
28 mgm.x.SetBit(mgm.x, mgm.maxBit, 0)
30 mgm.x.Xor(mgm.x, mgm.r)
36 zBytes := mgm.z.Bytes()
37 rem := len(xBuf) - len(zBytes)
38 for i = 0; i < rem; i++ {
41 copy(mgm.mulBuf[rem:], zBytes)