protected abstract BlockCipher DecryptBlock(BlockCipher block);
public virtual void Encrypt(Stream inStream, Stream outStream, byte[] key)
{
BinaryWriter binaryWriter = (BinaryWriter)null;
BinaryReader binaryReader = (BinaryReader)null;
this.Key = key;
int position = (int)outStream.Position;
int length = (int)inStream.Length;
int capacity = length + this.pBlockSizeValue / 8 + 4;
if (capacity % (this.pBlockSizeValue / 8) != 0)
{
capacity += this.pBlockSizeValue / 8 - capacity % (this.pBlockSizeValue / 8);
}
MemoryStream memoryStream = new MemoryStream(capacity);
try
{
memoryStream.SetLength((long)capacity);
binaryWriter = new BinaryWriter((Stream)memoryStream, this.Encoding);
binaryReader = new BinaryReader(inStream, this.Encoding);
binaryWriter.Write(new RNDGenerator().GetBytes(this.pBlockSizeValue / 8));
binaryWriter.Write(length);
binaryWriter.Write(binaryReader.ReadBytes(length));
binaryReader = new BinaryReader((Stream)memoryStream, this.Encoding);
binaryWriter = new BinaryWriter(outStream, this.Encoding);
BlockCipher block1 = new BlockCipher(this.pBlockSizeValue);
if (this.CipherMode == CipherMode.CBC || this.CipherMode == CipherMode.CFB)
{
if (this.pIVValue == null)
{
this.pIVValue = this.GenerateIV();
}
for (int index = 0; index < block1.Length && index < this.pIVValue.Length; ++index)
{
block1[index] = this.pIVValue[index];
}
}
memoryStream.Seek(0L, SeekOrigin.Begin);
outStream.Seek((long)position, SeekOrigin.Begin);
while (memoryStream.Position < memoryStream.Length)
{
switch (this.CipherMode)
{
case CipherMode.CBC:
BlockCipher blockCipher1 = this.EncryptBlock(new BlockCipher(binaryReader.ReadBytes(this.pBlockSizeValue / 8)) ^ block1);
block1 = blockCipher1;
binaryWriter.Write((byte[])blockCipher1);
continue;
case CipherMode.ECB:
BlockCipher blockCipher2 = this.EncryptBlock(new BlockCipher(binaryReader.ReadBytes(this.pBlockSizeValue / 8)));
binaryWriter.Write((byte[])blockCipher2);
continue;
case CipherMode.OFB:
block1 = this.EncryptBlock(block1);
BlockCipher blockCipher3 = new BlockCipher(binaryReader.ReadBytes(this.pBlockSizeValue / 8)) ^ block1;
block1 = blockCipher3;
binaryWriter.Write((byte[])blockCipher3);
continue;
case CipherMode.CFB:
block1 = this.EncryptBlock(block1);
BlockCipher blockCipher4 = new BlockCipher(binaryReader.ReadBytes(this.pBlockSizeValue / 8)) ^ block1;
block1 = blockCipher4;
binaryWriter.Write((byte[])blockCipher4);
continue;
case CipherMode.CTS:
BlockCipher block2 = new BlockCipher(binaryReader.ReadBytes(this.pBlockSizeValue / 8));
BlockCipher blockCipher5;
if (outStream.Position + (long)(this.pBlockSizeValue / 8 * 2) >= outStream.Length)
{
blockCipher5 = this.EncryptBlock(block2);
}
else
{
blockCipher5 = this.EncryptBlock(block2 ^ block1);
block1 = blockCipher5;
}
binaryWriter.Write((byte[])blockCipher5);
continue;
default:
throw new NotSupportedException("Cann't support the special CipherMode.");
}
}
}
catch (Exception ex)
{
throw ex;
}
finally
{
binaryReader?.Close();
binaryWriter?.Flush();
memoryStream?.Flush();
}
GC.Collect();
}
public virtual void Decrypt(Stream inStream, Stream outStream, byte[] key)
{
MemoryStream memoryStream = (MemoryStream)null;
BinaryWriter binaryWriter = (BinaryWriter)null;
BinaryReader binaryReader = (BinaryReader)null;
this.Key = key;
int length = (int)inStream.Length;
try
{
memoryStream = new MemoryStream(length);
binaryWriter = new BinaryWriter((Stream)memoryStream);
binaryReader = new BinaryReader(inStream, this.Encoding);
BlockCipher block1 = new BlockCipher(this.pBlockSizeValue);
BlockCipher block2;
while (inStream.Position < inStream.Length)
{
switch (this.CipherMode)
{
case CipherMode.CBC:
block2 = new BlockCipher(binaryReader.ReadBytes(this.pBlockSizeValue / 8));
BlockCipher blockCipher1 = (BlockCipher)block2.Clone();
block2 = this.DecryptBlock(block2);
block2 ^= block1;
block1 = blockCipher1;
binaryWriter.Write((byte[])block2);
continue;
case CipherMode.ECB:
block2 = new BlockCipher(binaryReader.ReadBytes(this.pBlockSizeValue / 8));
block2 = this.DecryptBlock(block2);
binaryWriter.Write((byte[])block2);
continue;
case CipherMode.OFB:
block2 = new BlockCipher(binaryReader.ReadBytes(this.pBlockSizeValue / 8));
BlockCipher blockCipher2 = this.EncryptBlock(block1);
BlockCipher blockCipher3 = (BlockCipher)block2.Clone();
block2 ^= blockCipher2;
block1 = blockCipher3;
binaryWriter.Write((byte[])block2);
continue;
case CipherMode.CFB:
block2 = new BlockCipher(binaryReader.ReadBytes(this.pBlockSizeValue / 8));
BlockCipher blockCipher4 = this.EncryptBlock(block1);
BlockCipher blockCipher5 = (BlockCipher)block2.Clone();
block2 ^= blockCipher4;
block1 = blockCipher5;
binaryWriter.Write((byte[])block2);
continue;
case CipherMode.CTS:
block2 = new BlockCipher(binaryReader.ReadBytes(this.pBlockSizeValue / 8));
if (outStream.Position + (long)(this.pBlockSizeValue / 8 * 2) >= outStream.Length)
{
block2 = this.DecryptBlock(block2);
}
else
{
BlockCipher blockCipher6 = (BlockCipher)block2.Clone();
block2 = this.DecryptBlock(block2);
block2 ^= block1;
block1 = blockCipher6;
}
binaryWriter.Write((byte[])block2);
continue;
default:
throw new NotSupportedException("Cann't support the special CipherMode.");
}
}
binaryReader = new BinaryReader((Stream)memoryStream, this.Encoding);
binaryWriter = new BinaryWriter(outStream, this.Encoding);
memoryStream.Seek((long)(this.pBlockSizeValue / 8), SeekOrigin.Begin);
int count = binaryReader.ReadInt32();
binaryWriter.Write(binaryReader.ReadBytes(count));
}
finally
{
binaryReader?.Close();
binaryWriter?.Flush();
memoryStream?.Flush();
}
GC.Collect();
}
