PaddedBufferedBlockCipher
using Org.BouncyCastle.Crypto.Modes;
using Org.BouncyCastle.Security;
using Org.BouncyCastle.Utilities;
using System;
namespace Org.BouncyCastle.Crypto.Paddings
{
public class PaddedBufferedBlockCipher : BufferedBlockCipher
{
private readonly IBlockCipherPadding m_padding;
public PaddedBufferedBlockCipher(IBlockCipher cipher, IBlockCipherPadding padding)
: this(EcbBlockCipher.GetBlockCipherMode(cipher), padding)
{
}
public PaddedBufferedBlockCipher(IBlockCipherMode cipherMode, IBlockCipherPadding padding)
: base(cipherMode)
{
m_padding = padding;
}
public PaddedBufferedBlockCipher(IBlockCipherMode cipherMode)
: this(cipherMode, new Pkcs7Padding())
{
}
public override void Init(bool forEncryption, ICipherParameters parameters)
{
base.forEncryption = forEncryption;
parameters = ParameterUtilities.GetRandom(parameters, out SecureRandom random);
Reset();
m_padding.Init(random);
m_cipherMode.Init(forEncryption, parameters);
}
public override int GetOutputSize(int length)
{
int num = bufOff + length;
int num2 = buf.Length;
if (!forEncryption)
return BufferedCipherBase.GetFullBlocksSize(num + num2 - 1, num2);
return BufferedCipherBase.GetFullBlocksSize(num, num2) + num2;
}
public override int GetUpdateOutputSize(int length)
{
return BufferedCipherBase.GetFullBlocksSize(bufOff + length - 1, buf.Length);
}
public override int ProcessByte(byte input, byte[] output, int outOff)
{
int result = 0;
if (bufOff == buf.Length) {
Check.OutputLength(output, outOff, buf.Length, "output buffer too short");
result = m_cipherMode.ProcessBlock(buf, 0, output, outOff);
bufOff = 0;
}
buf[bufOff++] = input;
return result;
}
public override int ProcessBytes(byte[] input, int inOff, int length, byte[] output, int outOff)
{
if (length < 1) {
if (length < 0)
throw new ArgumentException("Can't have a negative input length!");
return 0;
}
int num = 0;
int num2 = buf.Length;
int num3 = num2 - bufOff;
if (length > num3) {
int updateOutputSize = GetUpdateOutputSize(length);
Check.OutputLength(output, outOff, updateOutputSize, "output buffer too short");
Array.Copy(input, inOff, buf, bufOff, num3);
inOff += num3;
length -= num3;
if (output == input && Arrays.SegmentsOverlap(outOff, num2, inOff, length)) {
input = new byte[length];
Array.Copy(output, inOff, input, 0, length);
inOff = 0;
}
num = m_cipherMode.ProcessBlock(buf, 0, output, outOff);
bufOff = 0;
while (length > num2) {
num += m_cipherMode.ProcessBlock(input, inOff, output, outOff + num);
inOff += num2;
length -= num2;
}
}
Array.Copy(input, inOff, buf, bufOff, length);
bufOff += length;
return num;
}
public override int DoFinal(byte[] output, int outOff)
{
try {
int num = 0;
int num2 = buf.Length;
if (forEncryption) {
if (bufOff == num2) {
Check.OutputLength(output, outOff, num2 * 2, "output buffer too short");
num = m_cipherMode.ProcessBlock(buf, 0, output, outOff);
bufOff = 0;
} else
Check.OutputLength(output, outOff, num2, "output buffer too short");
m_padding.AddPadding(buf, bufOff);
num += m_cipherMode.ProcessBlock(buf, 0, output, outOff + num);
} else {
Check.DataLength(bufOff != num2, "last block incomplete in decryption");
num = m_cipherMode.ProcessBlock(buf, 0, buf, 0);
num -= m_padding.PadCount(buf);
Check.OutputLength(output, outOff, num, "output buffer too short");
Array.Copy(buf, 0, output, outOff, num);
}
return num;
} finally {
Reset();
}
}
}
}