/// <summary>
/// DES主要加密方法 输入输出64位
/// </summary>
/// <param name="qwPlain">64bit明文</param>
/// <param name="qwKey">64bit密钥</param>
/// <returns>64bit密文</returns>
public static QWORD Encrypt(QWORD qwPlain, QWORD qwKey)
{
QWORD L0R0 = DES_Table.Swap_IP(qwPlain);
QWORD T = DES_Table.Swap_PC1(qwKey);
DWORD C = (DWORD)((T & 0xFFFFFFF000000000) >> 32);
DWORD D = (DWORD)((T & 0x0000000FFFFFFF00) >> 4);
DWORD L = (DWORD)(L0R0 >> 32);
DWORD R = (DWORD)(L0R0);
int[] shiftTable =
{
1, 1, 2, 2,
2, 2, 2, 2,
1, 2, 2, 2,
2, 2, 2, 1
};
for (int round = 0; round < 16; ++round)
{
C = DES_Convert.RoundShiftLeft28(C, shiftTable[round]);
D = DES_Convert.RoundShiftLeft28(D, shiftTable[round]);
T = ((QWORD)(C & 0xFFFFFFF0) << 32) | ((QWORD)D << 4);
QWORD Ki = DES_Table.Swap_PC2(T);
DWORD temp = R;
R = DES_Table.Swap_P(DES_Table.Swap_S(DES_Table.Expand_R(R) ^ Ki)) ^ L;
L = temp;
}
QWORD R16L16 = ((QWORD)R << 32) | (QWORD)L;
QWORD qwCipher = DES_Table.Swap_T_IP(R16L16);
return(qwCipher);
}
/// <summary>
/// DES分组解密方法 输入byte数组 返回byte数组
/// </summary>
/// <param name="baCipher">明文byte数组</param>
/// <param name="qwKey">64bit密钥</param>
/// <param name="qwIV">64bit初始化向量，ECB模式无效</param>
/// <param name="mode">操作模式</param>
/// <returns>密文byte数组</returns>
public static byte[] DecryptBlockB(byte[] baCipher, QWORD qwKey, QWORD qwIV, Mode mode)
{
if (mode == Mode.CFB)
{
return(DES_Convert.QWORDToBytes_CFB(DecryptBlockQ(baCipher, qwKey, qwIV, mode)));
}
return(DES_Convert.QWORDToBytes(DecryptBlockQ(baCipher, qwKey, qwIV, mode)));
}
/// <summary>
/// DES分组加密方法 输入byte数组 返回byte数组
/// </summary>
/// <param name="baPlain">输入byte数组</param>
/// <param name="qwKey">64bit密钥</param>
/// <param name="qwIV">64bit初始化向量，ECB模式无效</param>
/// <param name="mode">操作模式</param>
/// <returns>密文byte数组</returns>
public static byte[] EncryptBlockB(byte[] baPlain, QWORD qwKey, QWORD qwIV, Mode mode)
{
if (mode == Mode.CFB)
{
return(DES_Convert.QWORDToBytes_CFB(EncryptBlockQ(baPlain, qwKey, qwIV, mode)));
}
return(DES_Convert.QWORDToBytes(EncryptBlockQ(baPlain, qwKey, qwIV, mode)));
}
/// <summary>
/// DES主要解密方法 输入输出64位
/// </summary>
/// <param name="qwCipher">64bit密文</param>
/// <param name="qwKey">64bit密钥</param>
/// <returns>64bit明文</returns>
public static QWORD Decrypt(QWORD qwCipher, QWORD qwKey)
{
QWORD L16R16 = DES_Table.Swap_IP(qwCipher);
DWORD L = (DWORD)L16R16;
DWORD R = (DWORD)(L16R16 >> 32);
QWORD T = DES_Table.Swap_PC1(qwKey);
DWORD C = (DWORD)((T & 0xFFFFFFF000000000) >> 32);
DWORD D = (DWORD)((T & 0x0000000FFFFFFF00) >> 4);
int[] shiftTable =
{
1, 1, 2, 2,
2, 2, 2, 2,
1, 2, 2, 2,
2, 2, 2, 1
};
List <QWORD> lsKey = new List <QWORD>();
for (int round = 0; round < 16; ++round)
{
C = DES_Convert.RoundShiftLeft28(C, shiftTable[round]);
D = DES_Convert.RoundShiftLeft28(D, shiftTable[round]);
T = ((QWORD)(C & 0xFFFFFFF0) << 32) | ((QWORD)D << 4);
lsKey.Add(DES_Table.Swap_PC2(T));
}
for (int round = 15; round >= 0; --round)
{
DWORD temp = R;
R = L;
L = DES_Table.Swap_P(DES_Table.Swap_S(DES_Table.Expand_R(R) ^ lsKey[round])) ^ temp;
}
QWORD L0R0 = ((QWORD)L << 32) | (QWORD)R;
QWORD qwPlain = DES_Table.Swap_T_IP(L0R0);
return(qwPlain);
}
