public bool Encrypt()
{
long totLength = reader.BaseStream.Length, currentLength = 0;
// 先输出加密后的IV，以供解密
writer.Write(DES.Encrypt(IV, key).ToByteArray());
lastAnswer = IV;
long roundCount = 0;
while (EncryptBlock() == 8)
{
currentLength += 8;
roundCount++;
if (roundCount % 100 == 0)
{
Program.Form.progressBar.Value = (int)(currentLength * 100.0 / totLength);
Application.DoEvents();
}
}
Program.Form.progressBar.Value = 100;
return(true);
}
private void LoadKeyButton_Click(object sender, EventArgs e)
{
if (busy)
{
return;
}
if (keyFileDialog.ShowDialog() == DialogResult.OK)
{
Bitset newKey = LoadKey(keyFileDialog.FileName);
if (newKey != null)
{
if (newKey.ToBigIntegerValue() == 0)
{
MessageBox.Show("0 不是一个合法的密钥。");
return;
}
Key = newKey;
textBoxKey.Text = Key.ToString();
textBoxRSAInput.Text = Key.ToBigIntegerValue().ToString();
}
}
}
/// <summary>
/// 轮函数的主处理函数
/// </summary>
/// <param name="input">输入的64比特（包括Li-1与Ri-1）</param>
/// <param name="key">输入的子密钥</param>
/// <returns>输出的64比特（包括Li与Ri）</returns>
public Bitset Process(Bitset input, Bitset key)
{
//判断输入是否合法
if (input.Length != 64 || key.Length != 48)
{
throw new ArgumentException("输入不合法");
}
// 拆成两个32比特，Ri不动，Li进行处理
Bitset left = input.LeftHalf();
Bitset right = input.RightHalf();
// 计算轮函数f值，先R进行E矩阵置换，从32比特变为48比特：
Bitset f = EMatrix.Perform(right);
// 然后将f值与密钥相异或
f = f.Xor(key);
// 将值拆成8个6bit串，输入S盒
Bitset[] groups = f.SplitByLength(6);
for (int i = 0; i < 8; ++i)
{
// 进行S盒变换
groups[i] = S[i].Perform(groups[i]);
}
// 将f和成一个01串
f = Bitset.Join(groups);
// 再经过P盒坐标置换
f = PBox.Perform(f);
// 与L_(i-1)异或
f = f.Xor(left);
//输出结果，注意没有经过左右交换SW
return(Bitset.Join(f, right));
}
public int EncryptBlock()
{
byte[] readByte = reader.ReadBytes(8);
byte[] newByte;
if (readByte.Length != 8)
{
newByte = new byte[8];
for (int i = 0; i < readByte.Length; ++i)
{
newByte[i] = readByte[i];
}
newByte[7] = (byte)((7 - readByte.Length) * 8);
}
else
{
newByte = readByte;
}
Bitset processData = new Bitset(newByte);
lastAnswer = DES.Encrypt(processData.Xor(lastAnswer), key);
byte[] writeByte = lastAnswer.ToByteArray();
writer.Write(writeByte);
return(readByte.Length);
}
private void RandomIVButton_Click(object sender, EventArgs e)
{
Log("生成随机初始向量：IV(64 bit)");
IV = Bitset.RandomGenerate(64);
IVText.Text = IV.ToString();
}
/// <summary>
/// 构造新的DES流
/// </summary>
/// <param name="inputReader">待加密/解密输入流</param>
/// <param name="inputKey">密钥</param>
/// <param name="inputWriter">结果输出流</param>
/// <param name="inputIV">初始向量，解密时不需要提供</param>
public DESStream(BinaryReader inputReader, Bitset inputKey, BinaryWriter inputWriter, Bitset inputIV = null)
{
reader = inputReader;
writer = inputWriter;
key = inputKey;
DES = new DESAlgorithm();
if (inputIV != null)
{
IV = inputIV;
}
else
{
IV = new Bitset(64);
}
}
/// <summary>
/// 解密方法
/// </summary>
/// <param name="data">密文</param>
/// <param name="key">密钥</param>
/// <returns>明文</returns>
public Bitset Decrypt(Bitset data, Bitset key)
{
return(Process(data, key, false));
}
/// <summary>
/// 加密方法
/// </summary>
/// <param name="data">明文</param>
/// <param name="key">密钥</param>
/// <returns>密文</returns>
public Bitset Encrypt(Bitset data, Bitset key)
{
return(Process(data, key, true));
}
/// <summary>
/// 复制构造函数
/// </summary>
/// <param name="rhs">待复制OldBitset</param>
public Bitset(Bitset rhs)
{
data = rhs.data.Clone() as bool[];
}
