BlockCipher
Base class for block cipher implementations.
using Renci.SshNet.Security.Cryptography.Ciphers;
using System;
namespace Renci.SshNet.Security.Cryptography
{
public abstract class BlockCipher : SymmetricCipher
{
private readonly CipherMode _mode;
private readonly CipherPadding _padding;
private readonly byte _blockSize;
public override byte MinimumSize => BlockSize;
public byte BlockSize => _blockSize;
protected BlockCipher(byte[] key, byte blockSize, CipherMode mode, CipherPadding padding)
: base(key)
{
_blockSize = blockSize;
_mode = mode;
_padding = padding;
_mode?.Init(this);
}
public override byte[] Encrypt(byte[] input, int offset, int length)
{
if (length % (int)_blockSize > 0) {
if (_padding == null)
throw new ArgumentException("data");
int num = _blockSize - length % (int)_blockSize;
input = _padding.Pad(input, offset, length, num);
length += num;
offset = 0;
}
byte[] array = new byte[length];
int num2 = 0;
for (int i = 0; i < length / (int)_blockSize; i++) {
num2 = ((_mode != null) ? (num2 + _mode.EncryptBlock(input, offset + i * _blockSize, _blockSize, array, i * _blockSize)) : (num2 + EncryptBlock(input, offset + i * _blockSize, _blockSize, array, i * _blockSize)));
}
if (num2 < length)
throw new InvalidOperationException("Encryption error.");
return array;
}
public override byte[] Decrypt(byte[] input)
{
return Decrypt(input, 0, input.Length);
}
public override byte[] Decrypt(byte[] input, int offset, int length)
{
if (length % (int)_blockSize > 0) {
if (_padding == null)
throw new ArgumentException("data");
input = _padding.Pad(_blockSize, input, offset, length);
offset = 0;
length = input.Length;
}
byte[] array = new byte[length];
int num = 0;
for (int i = 0; i < length / (int)_blockSize; i++) {
num = ((_mode != null) ? (num + _mode.DecryptBlock(input, offset + i * _blockSize, _blockSize, array, i * _blockSize)) : (num + DecryptBlock(input, offset + i * _blockSize, _blockSize, array, i * _blockSize)));
}
if (num < length)
throw new InvalidOperationException("Encryption error.");
return array;
}
}
}