Ejemplo n.º 1
0
// GenerateDecryptionKeys creates a white-boxed version of the AES key `key` for decryption, with any non-determinism
// generated by `seed`.  The `opts` argument works the same as above.
func GenerateDecryptionKeys(key, seed []byte, opts common.KeyGenerationOpts) (out Construction, inputMask, outputMask matrix.Matrix) {
	rs := common.NewRandomSource("Chow Decryption", seed)

	constr := saes.Construction{key}
	roundKeys := constr.StretchedKey()

	// Last key needs to be unshifted for decryption to work right.
	constr.UnShiftRows(roundKeys[10])

	skinny := func(pos int) table.Byte {
		return common.InvTBox{constr, 0x00, roundKeys[0][pos]}
	}

	wide := func(round, pos int) table.Word {
		if round == 0 {
			return table.ComposedToWord{
				common.InvTBox{constr, roundKeys[10][pos], roundKeys[9][pos]},
				common.InvTyiTable(pos % 4),
			}
		} else {
			return table.ComposedToWord{
				common.InvTBox{constr, 0x00, roundKeys[9-round][pos]},
				common.InvTyiTable(pos % 4),
			}
		}
	}

	generateKeys(&rs, opts, &out, &inputMask, &outputMask, common.UnShiftRows, skinny, wide)

	return
}
Ejemplo n.º 2
0
// GenerateEncryptionKeys creates a white-boxed version of the AES key `key` for encryption, with any non-determinism
// generated by `seed`.  The `opts` specifies what type of input and output masks we put on the construction and should
// be either IndependentMasks, SameMasks, or MatchingMasks.
func GenerateEncryptionKeys(key, seed []byte, opts common.KeyGenerationOpts) (out Construction, inputMask, outputMask matrix.Matrix) {
	rs := common.NewRandomSource("Chow Encryption", seed)

	constr := saes.Construction{key}
	roundKeys := constr.StretchedKey()

	// Apply ShiftRows to round keys 0 to 9.
	for k := 0; k < 10; k++ {
		constr.ShiftRows(roundKeys[k])
	}

	skinny := func(pos int) table.Byte {
		return common.TBox{constr, roundKeys[9][pos], roundKeys[10][pos]}
	}

	wide := func(round, pos int) table.Word {
		return table.ComposedToWord{
			common.TBox{constr, roundKeys[round][pos], 0x00},
			common.TyiTable(pos % 4),
		}
	}

	generateKeys(&rs, opts, &out, &inputMask, &outputMask, common.ShiftRows, skinny, wide)

	return
}
Ejemplo n.º 3
0
// GenerateDecryptionKeys creates a white-boxed version of the AES key `key` for decryption, with any non-determinism
// generated by `seed`.
func GenerateDecryptionKeys(key, seed []byte, opts common.KeyGenerationOpts) (out Construction, inputMask, outputMask matrix.Matrix) {
	rs := common.NewRandomSource("Xiao Decryption", seed)

	constr := saes.Construction{key}
	roundKeys := constr.StretchedKey()

	// Apply UnShiftRows to round keys 10.
	constr.UnShiftRows(roundKeys[10])

	hidden := func(round, pos int) table.DoubleToWord {
		if round == 0 {
			return TBoxMixCol{
				[2]table.Byte{
					common.InvTBox{constr, roundKeys[10][pos+0], roundKeys[9][pos+0]},
					common.InvTBox{constr, roundKeys[10][pos+1], roundKeys[9][pos+1]},
				},
				UnMixColumns,
				SideFromPos(pos),
			}
		} else if 0 < round && round < 9 {
			return TBoxMixCol{
				[2]table.Byte{
					common.InvTBox{constr, 0x00, roundKeys[9-round][pos+0]},
					common.InvTBox{constr, 0x00, roundKeys[9-round][pos+1]},
				},
				UnMixColumns,
				SideFromPos(pos),
			}
		} else {
			return TBox{
				[2]table.Byte{
					common.InvTBox{constr, 0x00, roundKeys[0][pos+0]},
					common.InvTBox{constr, 0x00, roundKeys[0][pos+1]},
				},
				SideFromPos(pos),
			}
		}
	}

	common.GenerateMasks(&rs, opts, &inputMask, &outputMask)
	generateRoundMaterial(&rs, &out, hidden)
	generateBarriers(&rs, &out, &inputMask, &outputMask, &UnShiftRows)

	return out, inputMask, outputMask
}
Ejemplo n.º 4
0
// GenerateEncryptionKeys creates a white-boxed version of the AES key `key` for encryption, with any non-determinism
// generated by `seed`.
func GenerateEncryptionKeys(key, seed []byte, opts common.KeyGenerationOpts) (out Construction, inputMask, outputMask matrix.Matrix) {
	rs := common.NewRandomSource("Xiao Encryption", seed)

	constr := saes.Construction{key}
	roundKeys := constr.StretchedKey()

	// Apply ShiftRows to round keys 0 to 9.
	for k := 0; k < 10; k++ {
		constr.ShiftRows(roundKeys[k])
	}

	hidden := func(round, pos int) table.DoubleToWord {
		if round == 9 {
			return TBox{
				[2]table.Byte{
					common.TBox{constr, roundKeys[9][pos+0], roundKeys[10][pos+0]},
					common.TBox{constr, roundKeys[9][pos+1], roundKeys[10][pos+1]},
				},
				SideFromPos(pos),
			}
		} else {
			return TBoxMixCol{
				[2]table.Byte{
					common.TBox{constr, roundKeys[round][pos+0], 0x00},
					common.TBox{constr, roundKeys[round][pos+1], 0x00},
				},
				MixColumns,
				SideFromPos(pos),
			}
		}
	}

	common.GenerateMasks(&rs, opts, &inputMask, &outputMask)
	generateRoundMaterial(&rs, &out, hidden)
	generateBarriers(&rs, &out, &inputMask, &outputMask, &ShiftRows)

	return out, inputMask, outputMask
}