public byte[] Decrypt(byte[] message, CryptoPadding padding = null, bool checkSign = false)
{
// Reinterpret encrypted message as a number
BigInteger cryptomessage = new BigInteger(message);
// Reverse encryption
message = Support.ModExp(cryptomessage, checkSign ? e : d, n).ToByteArray();
// Remove fixed padding
byte[] b1 = new byte[message.Length - 1];
Array.Copy(message, b1, message.Length - 1);
message = b1;
// Remove dynamic padding
message = (padding ?? NO_PADDING).Unpad(message);
return(message);
}
public byte[] Decrypt(byte[] message, CryptoPadding padding)
{
// Reinterpret encrypted message as a number
BigInteger cryptomessage = new BigInteger(message);
// Reverse encryption
message = Support.ModExp(cryptomessage, d, n).ToByteArray();
// Remove fixed padding
byte[] b1 = new byte[message.Length - 1];
Array.Copy(message, b1, message.Length - 1);
message = b1;
// Remove dynamic padding
message = padding.Unpad(message);
return(message);
}
public byte[] Encrypt(byte[] message, CryptoPadding padding = null, bool sign = false)
{
// Apply dynamic padding
message = (padding ?? NO_PADDING).Pad(message);
// Apply fixed padding
byte[] b1 = new byte[message.Length + 1];
Array.Copy(message, b1, message.Length);
b1[message.Length] = 1;
message = b1;
// Represent message as a number
BigInteger m = new BigInteger(message);
// Encrypt message
BigInteger cryptomessage = Support.ModExp(m, sign ? d : e, n);
// Convert encrypted message back to bytes
return(cryptomessage.ToByteArray());
}
public static string SerializePadding(CryptoPadding padding)
{
XmlDocument doc = new XmlDocument();
doc.AppendChild(padding.GetParameters().Compile(doc));
string output;
using (var stream = new MemoryStream())
{
XmlTextWriter writer = new XmlTextWriter(stream, Encoding.UTF8);
doc.WriteTo(writer);
writer.Flush();
stream.Position = 0;
using (var reader = new StreamReader(stream))
{
output = reader.ReadToEnd();
}
}
return(output);
}
// Encrypt (duh) public byte[] EncryptString(string message, Encoding encoding = null, CryptoPadding padding = null, bool sign = false) => Encrypt((encoding ?? DEFAULT_ENCODING).GetBytes(message), padding, sign);
// Decrypt (duh) public string DecryptString(byte[] message, Encoding encoding = null, CryptoPadding padding = null, bool checkSign = false) => new string((encoding ?? DEFAULT_ENCODING).GetChars(Decrypt(message, padding, checkSign)));
// WIP public static string NetSerialize(CryptoPadding padding) => NetSerialize(padding.GetParameters(), new StringBuilder()).ToString();
public SequentialPadding WithPadding(CryptoPadding padding)
{
pads.Add(padding);
return(this);
}
public string DecryptString(byte[] message, CryptoPadding padding) => new string(DEFAULT_ENCODING.GetChars(Decrypt(message, padding)));
public string DecryptString(byte[] message, Encoding encoding, CryptoPadding padding) => new string(encoding.GetChars(Decrypt(message, padding)));
public byte[] EncryptString(string message, Encoding encoding, CryptoPadding padding) => Encrypt(encoding.GetBytes(message), padding);
public byte[] EncryptString(string message, CryptoPadding padding) => Encrypt(DEFAULT_ENCODING.GetBytes(message), padding);