/// <summary>
/// Encrypts a byte array using the specified encryption algorithm,
/// key, and initialization vector after adding eight bytes of
/// cryptographic salt.
/// </summary>
/// <param name="input">The clear text array.</param>
/// <param name="algorithm">The symmetric algorithm name.</param>
/// <param name="key">The encryption key.</param>
/// <param name="IV">The initialization vector.</param>
/// <returns>The encrypted output.</returns>
/// <remarks>
/// <note>
/// This method returns an zero length result if the input
/// array has zero length.
/// </note>
/// </remarks>
public static byte[] EncryptWithSalt8(byte[] input, string algorithm, byte[] key, byte[] IV)
{
if (input.Length == 0)
{
return(new byte[0]);
}
using (BlockEncryptor encryptor = new BlockEncryptor(algorithm, key, IV))
return(encryptor.Encrypt(Helper.Concat(Crypto.GetSalt8(), input)));
}
/// <summary>
/// Performs a secure symmetric encryption including cryptographic salt, padding, and
/// data validation.
/// </summary>
/// <param name="symmetricKey">The symmetric algorithm arguments.</param>
/// <param name="plainText">The unencrypted data.</param>
/// <param name="paddedSize">Specifies the minimum padded size of the encrypted content.</param>
/// <returns>The encrypted result.</returns>
public static byte[] Encrypt(SymmetricKey symmetricKey, byte[] plainText, int paddedSize)
{
EnhancedMemoryStream output = new EnhancedMemoryStream(Math.Max(plainText.Length, paddedSize) + 512);
EnhancedMemoryStream ms = new EnhancedMemoryStream(512);
BlockEncryptor encryptor = new BlockEncryptor(symmetricKey);
try
{
// Write header fields
output.WriteInt32(Magic);
output.WriteInt32(0);
// Write encrypted contents
ms.WriteInt32(Magic);
ms.WriteBytesNoLen(Crypto.GetSalt8());
ms.WriteBytes32(plainText);
for (int i = plainText.Length; i < paddedSize; i++)
{
ms.WriteByte((byte)i); // Padding bytes
}
output.WriteBytes32(encryptor.Encrypt(ms.ToArray()));
// That's it, we're done.
return(output.ToArray());
}
finally
{
if (encryptor != null)
{
encryptor.Dispose();
}
output.Close();
ms.Close();
}
}
/// <summary>
/// Encrypts a byte array using a combination of an asymmetric RSA key and the
/// specified symmetric encryption algorithm and a one-time key generated by
/// the method.
/// </summary>
/// <param name="rsaKey">The encrypting RSA key as XML or as a secure key container name.</param>
/// <param name="plainText">The data to be encrypted.</param>
/// <param name="algorithm">The symmetric encryption algorithm name.</param>
/// <param name="keySize">The one-time symmetric key size to generate in bits.</param>
/// <param name="paddedSize">Specifies the minimum padded size of the encrypted content.</param>
/// <param name="symmetricKey">Returns as the symmetric encryption algorithm arguments.</param>
/// <returns>The encrypted result.</returns>
/// <remarks>
/// <para>
/// Note that applications should take some care to ensure that the <paramref name="symmetricKey" />
/// value return is disposed so that the symmetric encryption key will be cleared.
/// </para>
/// <para>
/// The current supported cross platform encryption algorithms
/// are: "DES", "RC2", "TripleDES", and "AES" (Rijndael).
/// </para>
/// </remarks>
/// <exception cref="ArgumentException">Thrown if the requested encryption algorithm is unknown.</exception>
public static byte[] Encrypt(string rsaKey, byte[] plainText, string algorithm, int keySize, int paddedSize,
out SymmetricKey symmetricKey)
{
EnhancedMemoryStream output = new EnhancedMemoryStream(Math.Max(plainText.Length, paddedSize) + 512);
EnhancedMemoryStream ms = new EnhancedMemoryStream(512);
BlockEncryptor encryptor = null;
byte[] symKey;
byte[] symIV;
Crypto.GenerateSymmetricKey(algorithm, keySize, out symKey, out symIV);
encryptor = new BlockEncryptor(algorithm, symKey, symIV);
symmetricKey = new SymmetricKey(algorithm, (byte[])symKey.Clone(), (byte[])symIV.Clone());
try
{
// Write header fields
output.WriteInt32(Magic);
output.WriteInt32(0);
// Write encryption Info
ms.WriteString16(algorithm);
ms.WriteBytes16(symKey);
ms.WriteBytes16(symIV);
ms.WriteBytesNoLen(Crypto.GetSalt8());
output.WriteBytes16(AsymmetricCrypto.Encrypt(CryptoAlgorithm.RSA, rsaKey, ms.ToArray()));
// Write encrypted contents
ms.SetLength(0);
ms.WriteInt32(Magic);
ms.WriteBytesNoLen(Crypto.GetSalt8());
ms.WriteBytes32(plainText);
for (int i = plainText.Length; i < paddedSize; i++)
{
ms.WriteByte((byte)i); // Padding bytes
}
output.WriteBytes32(encryptor.Encrypt(ms.ToArray()));
// That's it, we're done.
return(output.ToArray());
}
finally
{
if (symKey != null)
{
Array.Clear(symKey, 0, symKey.Length);
}
if (symIV != null)
{
Array.Clear(symIV, 0, symIV.Length);
}
if (encryptor != null)
{
encryptor.Dispose();
}
output.Close();
ms.Close();
}
}
/// <summary>
/// Encodes a string as UTF8 and encryptes it using the specified
/// encryption algorithm, key, and initialization vector after
/// adding eight bytes of cryptographic salt.
/// </summary>
/// <param name="input">The clear text string.</param>
/// <param name="algorithm">The symmetric algorithm name.</param>
/// <param name="key">The encryption key.</param>
/// <param name="IV">The initialization vector.</param>
/// <returns>The encrypted output.</returns>
public static byte[] EncryptStringWithSalt8(string input, string algorithm, byte[] key, byte[] IV)
{
using (BlockEncryptor encryptor = new BlockEncryptor(algorithm, key, IV))
return(encryptor.Encrypt(Helper.Concat(Crypto.GetSalt8(), Helper.ToUTF8(input))));
}
/// <summary>
/// Encrypts a byte array using the specified encryption algorithm,
/// key, and initialization vector.
/// </summary>
/// <param name="input">The clear text array.</param>
/// <param name="algorithm">The symmetric algorithm name.</param>
/// <param name="key">The encryption key.</param>
/// <param name="IV">The initialization vector.</param>
/// <returns>The encrypted output.</returns>
public static byte[] Encrypt(byte[] input, string algorithm, byte[] key, byte[] IV)
{
using (BlockEncryptor encryptor = new BlockEncryptor(algorithm, key, IV))
return(encryptor.Encrypt(input));
}
