public GenericGcmModeCryptoTransform(IGenericBlockCipher cipher, bool forEncryption,
byte[] iv, byte[] additional, int tagLength)
{
if (cipher == null)
{
throw new ArgumentNullException("cipher");
}
if (cipher.BlockSize != BLOCK_SIZE)
{
throw new ArgumentException("cipher");
}
if (iv == null)
{
throw new ArgumentNullException("iv");
}
if (additional == null)
{
throw new ArgumentNullException("additional");
}
if (tagLength < 12 || tagLength > 16)
{
throw new ArgumentException("tagLength " + tagLength);
}
_cipher = cipher;
_encrypting = forEncryption;
_tagLength = tagLength;
_cipher.Encrypt(_H, 0, _H, 0);
if (iv.Length == 12)
{
Buffer.BlockCopy(iv, 0, _J0, 0, 12);
_J0[_J0.Length - 1] = 0x01;
}
else
{
// Construct last hashed block from IV length
byte[] lengthBytes = BitConverter.GetBytes((UInt64)iv.Length * 8);
if (BitConverter.IsLittleEndian)
{
Array.Reverse(lengthBytes);
}
byte[] lastBlock = new byte[BLOCK_SIZE];
Buffer.BlockCopy(lengthBytes, 0, lastBlock, 8, 8);
// Hash the IV and length block to get J0
GHASH(iv, _J0);
GHASH(_J0, lastBlock, 0, lastBlock.Length, _J0);
}
GHASH(additional, _originalS);
_additionalLength = (UInt64)additional.Length;
Reset();
}
public GenericCbcModeCryptoTransform(IGenericBlockCipher cipher, bool forEncryption, byte[] iv)
{
if (cipher == null)
throw new ArgumentNullException("cipher");
if (iv == null)
throw new ArgumentNullException("iv");
if (iv.Length != cipher.BlockSize)
throw new ArgumentException("IV length " + iv.Length + ", expected " + cipher.BlockSize);
_cipher = cipher;
_blockSize = cipher.BlockSize;
_encrypting = forEncryption;
_originalIV = (byte[])iv.Clone();
_currentIV = new byte[_blockSize];
Reset();
}
public GenericGcmModeCryptoTransform(IGenericBlockCipher cipher, bool forEncryption,
byte[] iv, byte[] additional, int tagLength)
{
if (cipher == null)
throw new ArgumentNullException("cipher");
if (cipher.BlockSize != BLOCK_SIZE)
throw new ArgumentException("cipher");
if (iv == null)
throw new ArgumentNullException("iv");
if (additional == null)
throw new ArgumentNullException("additional");
if (tagLength < 12 || tagLength > 16)
throw new ArgumentException("tagLength " + tagLength);
_cipher = cipher;
_encrypting = forEncryption;
_tagLength = tagLength;
_cipher.Encrypt(_H, 0, _H, 0);
if (iv.Length == 12) {
Buffer.BlockCopy(iv, 0, _J0, 0, 12);
_J0[_J0.Length-1] = 0x01;
} else {
// Construct last hashed block from IV length
byte[] lengthBytes = BitConverter.GetBytes((UInt64)iv.Length*8);
if (BitConverter.IsLittleEndian) {
Array.Reverse(lengthBytes);
}
byte[] lastBlock = new byte[BLOCK_SIZE];
Buffer.BlockCopy(lengthBytes, 0, lastBlock, 8, 8);
// Hash the IV and length block to get J0
GHASH(iv, _J0);
GHASH(_J0, lastBlock, 0, lastBlock.Length, _J0);
}
GHASH(additional, _originalS);
_additionalLength = (UInt64)additional.Length;
Reset();
}
public GenericCbcModeCryptoTransform(IGenericBlockCipher cipher, bool forEncryption, byte[] iv)
{
if (cipher == null)
{
throw new ArgumentNullException("cipher");
}
if (iv == null)
{
throw new ArgumentNullException("iv");
}
if (iv.Length != cipher.BlockSize)
{
throw new ArgumentException("IV length " + iv.Length + ", expected " + cipher.BlockSize);
}
_cipher = cipher;
_blockSize = cipher.BlockSize;
_encrypting = forEncryption;
_originalIV = (byte[])iv.Clone();
_currentIV = new byte[_blockSize];
Reset();
}
