public Message()
{
msg = "";
externalType = ExternalMsgTypes.Transfer;
internalType = InternalMsgTypes.MessageTransfer;
}
public bool Decrypt(string MyPrivateKey, string SourcePublicKey)
{
//Decrypt Process
try
{
//Message Signing
RSACryptoServiceProvider rsaCryptoServiceProvider = new RSACryptoServiceProvider(1024);
rsaCryptoServiceProvider.FromXmlString(SourcePublicKey);
SHA1Managed sha1 = new SHA1Managed();
byte[] data = Convert.FromBase64String(msg);
byte[] signature = new byte[128];
byte[] messagebytes = new byte[data.Length - 128];
Array.Copy(data, 0, signature, 0, 128);
Array.Copy(data, 128, messagebytes, 0, messagebytes.Length);
byte[] hash = sha1.ComputeHash(messagebytes);
if (!rsaCryptoServiceProvider.VerifyHash(hash, CryptoConfig.MapNameToOID("SHA1"), signature))
{
//MessageBox.Show("Couldn't verify the message, please verify your certificate.");
return(false);
}
//House-Keeping
int keyLen = BitConverter.ToInt32(messagebytes, 0);
int messageLen = BitConverter.ToInt32(messagebytes, 4);
byte[] keybytes = new byte[keyLen];
byte[] msgbytes = new byte[messageLen];
Array.Copy(messagebytes, 8, keybytes, 0, keyLen);
Array.Copy(messagebytes, 8 + keyLen, msgbytes, 0, messageLen);
//Key Decryption
RSACryptoServiceProvider rsaCryptoServiceProvider2 = new RSACryptoServiceProvider(1024);
rsaCryptoServiceProvider2.FromXmlString(MyPrivateKey);
int base64BlockSize = ((1024 / 8) % 3 != 0) ? (((1024 / 8) / 3) * 4) + 4 : ((1024 / 8) / 3) * 4;
string TempStr = Convert.ToBase64String(keybytes);
int iterations = TempStr.Length / base64BlockSize;
ArrayList arrayList = new ArrayList();
for (int i = 0; i < iterations; i++)
{
byte[] encryptedBytes = Convert.FromBase64String(TempStr.Substring(base64BlockSize * i, base64BlockSize));
Array.Reverse(encryptedBytes);
arrayList.AddRange(rsaCryptoServiceProvider2.Decrypt(encryptedBytes, false));
}
string AES_KEY = Convert.ToBase64String(arrayList.ToArray(Type.GetType("System.Byte")) as byte[]);
//Decrypt AES 128
byte[] DecryptedKey = Convert.FromBase64String(AES_KEY);
SharpPrivacy.Cipher.SymmetricAlgorithm SA = null;
SA = CipherHelper.CreateSymAlgorithm(SymAlgorithms.AES128);
SA.Key = DecryptedKey;
SA.IV = SA.Key;
SharpPrivacy.Cipher.ICryptoTransform Decryptor = SA.CreateDecryptor();
byte[] Result = new byte[msgbytes.Length];
Decryptor.TransformBlock(msgbytes, 0, msgbytes.Length, ref Result, 0);
UnicodeEncoding UE = new UnicodeEncoding();
msg = UnicodeEncoding.ASCII.GetString(Result);
string Temp = Convert.ToBase64String(Result);
string temp2 = UnicodeEncoding.ASCII.GetString(Result);
string temp3 = UnicodeEncoding.Unicode.GetString(Result);
string temp4 = UnicodeEncoding.UTF32.GetString(Result);
string temp5 = UnicodeEncoding.UTF8.GetString(Result);
if (msg.Length > 0)
{
internalType = (InternalMsgTypes)Convert.ToInt32(msg[0].ToString());
int source_Lenght = Convert.ToInt32(msg[1].ToString());
source_name = msg.Substring(2, source_Lenght);
msg = msg.Substring(source_Lenght + 2, msg.Length - source_Lenght - 2);
}
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
return(false);
}
return(true);
}
