// GoGOST -- Pure Go GOST cryptographic functions library
// 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
// the Free Software Foundation, version 3 of the License.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

package gost28147

// Sbox is a representation of eight substitution boxes.
type Sbox [8][16]uint8

var (
	SboxIdGost2814789TestParamSet = Sbox([8][16]uint8{
		{4, 2, 15, 5, 9, 1, 0, 8, 14, 3, 11, 12, 13, 7, 10, 6},
		{12, 9, 15, 14, 8, 1, 3, 10, 2, 7, 4, 13, 6, 0, 11, 5},
		{13, 8, 14, 12, 7, 3, 9, 10, 1, 5, 2, 4, 6, 15, 0, 11},
		{14, 9, 11, 2, 5, 15, 7, 1, 0, 13, 12, 6, 10, 4, 3, 8},
		{3, 14, 5, 9, 6, 8, 0, 13, 10, 11, 7, 12, 2, 1, 15, 4},
		{8, 15, 6, 11, 1, 9, 12, 5, 13, 3, 7, 10, 0, 14, 2, 4},
		{9, 11, 12, 0, 3, 6, 7, 5, 4, 8, 14, 15, 1, 10, 2, 13},
		{12, 6, 5, 2, 11, 0, 9, 13, 3, 14, 7, 10, 15, 4, 1, 8},
	})
	SboxIdGost2814789CryptoProAParamSet = Sbox([8][16]uint8{
		{9, 6, 3, 2, 8, 11, 1, 7, 10, 4, 14, 15, 12, 0, 13, 5},
		{3, 7, 14, 9, 8, 10, 15, 0, 5, 2, 6, 12, 11, 4, 13, 1},
		{14, 4, 6, 2, 11, 3, 13, 8, 12, 15, 5, 10, 0, 7, 1, 9},
		{14, 7, 10, 12, 13, 1, 3, 9, 0, 2, 11, 4, 15, 8, 5, 6},
		{11, 5, 1, 9, 8, 13, 15, 0, 14, 4, 2, 3, 12, 7, 10, 6},
		{3, 10, 13, 12, 1, 2, 0, 11, 7, 5, 9, 4, 8, 15, 14, 6},
		{1, 13, 2, 9, 7, 10, 6, 0, 8, 12, 4, 5, 15, 3, 11, 14},
		{11, 10, 15, 5, 0, 12, 14, 8, 6, 2, 3, 9, 1, 7, 13, 4},
	})
	SboxIdGost2814789CryptoProBParamSet = Sbox([8][16]uint8{
		{8, 4, 11, 1, 3, 5, 0, 9, 2, 14, 10, 12, 13, 6, 7, 15},
		{0, 1, 2, 10, 4, 13, 5, 12, 9, 7, 3, 15, 11, 8, 6, 14},
		{14, 12, 0, 10, 9, 2, 13, 11, 7, 5, 8, 15, 3, 6, 1, 4},
		{7, 5, 0, 13, 11, 6, 1, 2, 3, 10, 12, 15, 4, 14, 9, 8},
		{2, 7, 12, 15, 9, 5, 10, 11, 1, 4, 0, 13, 6, 8, 14, 3},
		{8, 3, 2, 6, 4, 13, 14, 11, 12, 1, 7, 15, 10, 0, 9, 5},
		{5, 2, 10, 11, 9, 1, 12, 3, 7, 4, 13, 0, 6, 15, 8, 14},
		{0, 4, 11, 14, 8, 3, 7, 1, 10, 2, 9, 6, 15, 13, 5, 12},
	})
	SboxIdGost2814789CryptoProCParamSet = Sbox([8][16]uint8{
		{1, 11, 12, 2, 9, 13, 0, 15, 4, 5, 8, 14, 10, 7, 6, 3},
		{0, 1, 7, 13, 11, 4, 5, 2, 8, 14, 15, 12, 9, 10, 6, 3},
		{8, 2, 5, 0, 4, 9, 15, 10, 3, 7, 12, 13, 6, 14, 1, 11},
		{3, 6, 0, 1, 5, 13, 10, 8, 11, 2, 9, 7, 14, 15, 12, 4},
		{8, 13, 11, 0, 4, 5, 1, 2, 9, 3, 12, 14, 6, 15, 10, 7},
		{12, 9, 11, 1, 8, 14, 2, 4, 7, 3, 6, 5, 10, 0, 15, 13},
		{10, 9, 6, 8, 13, 14, 2, 0, 15, 3, 5, 11, 4, 1, 12, 7},
		{7, 4, 0, 5, 10, 2, 15, 14, 12, 6, 1, 11, 13, 9, 3, 8},
	})
	SboxIdGost2814789CryptoProDParamSet = Sbox([8][16]uint8{
		{15, 12, 2, 10, 6, 4, 5, 0, 7, 9, 14, 13, 1, 11, 8, 3},
		{11, 6, 3, 4, 12, 15, 14, 2, 7, 13, 8, 0, 5, 10, 9, 1},
		{1, 12, 11, 0, 15, 14, 6, 5, 10, 13, 4, 8, 9, 3, 7, 2},
		{1, 5, 14, 12, 10, 7, 0, 13, 6, 2, 11, 4, 9, 3, 15, 8},
		{0, 12, 8, 9, 13, 2, 10, 11, 7, 3, 6, 5, 4, 14, 15, 1},
		{8, 0, 15, 3, 2, 5, 14, 11, 1, 10, 4, 7, 12, 9, 13, 6},
		{3, 0, 6, 15, 1, 14, 9, 2, 13, 8, 12, 4, 11, 10, 5, 7},
		{1, 10, 6, 8, 15, 11, 0, 4, 12, 3, 5, 9, 7, 13, 2, 14},
	})
	SboxIdtc26gost28147paramZ = Sbox([8][16]uint8{
		{12, 4, 6, 2, 10, 5, 11, 9, 14, 8, 13, 7, 0, 3, 15, 1},
		{6, 8, 2, 3, 9, 10, 5, 12, 1, 14, 4, 7, 11, 13, 0, 15},
		{11, 3, 5, 8, 2, 15, 10, 13, 14, 1, 7, 4, 12, 9, 6, 0},
		{12, 8, 2, 1, 13, 4, 15, 6, 7, 0, 10, 5, 3, 14, 9, 11},
		{7, 15, 5, 10, 8, 1, 6, 13, 0, 9, 3, 14, 11, 4, 2, 12},
		{5, 13, 15, 6, 9, 2, 12, 10, 11, 7, 8, 1, 4, 3, 14, 0},
		{8, 14, 2, 5, 6, 9, 1, 12, 15, 4, 11, 0, 13, 10, 3, 7},
		{1, 7, 14, 13, 0, 5, 8, 3, 4, 15, 10, 6, 9, 12, 11, 2},
	})
	SboxIdGostR341194TestParamSet = Sbox([8][16]uint8{
		{4, 10, 9, 2, 13, 8, 0, 14, 6, 11, 1, 12, 7, 15, 5, 3},
		{14, 11, 4, 12, 6, 13, 15, 10, 2, 3, 8, 1, 0, 7, 5, 9},
		{5, 8, 1, 13, 10, 3, 4, 2, 14, 15, 12, 7, 6, 0, 9, 11},
		{7, 13, 10, 1, 0, 8, 9, 15, 14, 4, 6, 12, 11, 2, 5, 3},
		{6, 12, 7, 1, 5, 15, 13, 8, 4, 10, 9, 14, 0, 3, 11, 2},
		{4, 11, 10, 0, 7, 2, 1, 13, 3, 6, 8, 5, 9, 12, 15, 14},
		{13, 11, 4, 1, 3, 15, 5, 9, 0, 10, 14, 7, 6, 8, 2, 12},
		{1, 15, 13, 0, 5, 7, 10, 4, 9, 2, 3, 14, 6, 11, 8, 12},
	})
	SboxAppliedCryptographyParamSet    = SboxIdGostR341194TestParamSet
	SboxIdGostR341194CryptoProParamSet = Sbox([8][16]uint8{
		{10, 4, 5, 6, 8, 1, 3, 7, 13, 12, 14, 0, 9, 2, 11, 15},
		{5, 15, 4, 0, 2, 13, 11, 9, 1, 7, 6, 3, 12, 14, 10, 8},
		{7, 15, 12, 14, 9, 4, 1, 0, 3, 11, 5, 2, 6, 10, 8, 13},
		{4, 10, 7, 12, 0, 15, 2, 8, 14, 1, 6, 5, 13, 11, 9, 3},
		{7, 6, 4, 11, 9, 12, 2, 10, 1, 8, 0, 14, 15, 13, 3, 5},
		{7, 6, 2, 4, 13, 9, 15, 0, 10, 1, 5, 11, 8, 14, 12, 3},
		{13, 14, 4, 1, 7, 0, 5, 10, 3, 12, 8, 15, 6, 2, 9, 11},
		{1, 3, 10, 9, 5, 11, 4, 15, 8, 6, 7, 14, 13, 0, 2, 12},
	})
	SboxEACParamSet = Sbox([8][16]uint8{
		{11, 4, 8, 10, 9, 7, 0, 3, 1, 6, 2, 15, 14, 5, 12, 13},
		{1, 7, 14, 9, 11, 3, 15, 12, 0, 5, 4, 6, 13, 10, 8, 2},
		{7, 3, 1, 9, 2, 4, 13, 15, 8, 10, 12, 6, 5, 0, 11, 14},
		{10, 5, 15, 7, 14, 11, 3, 9, 2, 8, 1, 12, 0, 4, 6, 13},
		{0, 14, 6, 11, 9, 3, 8, 4, 12, 15, 10, 5, 13, 7, 1, 2},
		{9, 2, 11, 12, 0, 4, 5, 6, 3, 15, 13, 8, 1, 7, 14, 10},
		{4, 0, 14, 1, 5, 11, 8, 3, 12, 2, 9, 7, 6, 10, 13, 15},
		{7, 14, 12, 13, 9, 4, 8, 15, 10, 2, 6, 0, 3, 11, 5, 1},
	})
	SboxDefault = &SboxIdGost2814789CryptoProAParamSet
)

// Sbox substitution itself.
func (s *Sbox) k(n nv) nv {
	return nv(s[0][(n>>0)&0x0F])<<0 +
		nv(s[1][(n>>4)&0x0F])<<4 +
		nv(s[2][(n>>8)&0x0F])<<8 +
		nv(s[3][(n>>12)&0x0F])<<12 +
		nv(s[4][(n>>16)&0x0F])<<16 +
		nv(s[5][(n>>20)&0x0F])<<20 +
		nv(s[6][(n>>24)&0x0F])<<24 +
		nv(s[7][(n>>28)&0x0F])<<28
}