public void OutgoingMessage(ref Message_Private OutgoingMessage, ref bool ContinueToSend)
{
if (this.EnabledMenu.Checked)
{
//ENCRYPT THE MESSAGE WITH THE KEYS WE HAVE BEEN PROVIDED
EncryptedWrapper tmpMessage = EncryptedWrapper.EncryptMessage(OutgoingMessage.Message, this.PublicKeys);
OutgoingMessage.Message = Convert.ToBase64String(EncryptedWrapper.Serialize(tmpMessage));
}
}
public static string DecryptMessage(EncryptedWrapper Message, byte[] PrivateKey)
{
byte[] MessageKey = null;
byte[] MessageIV = null;
using (RSACryptoServiceProvider tmpRSA = new RSACryptoServiceProvider())
{
tmpRSA.ImportCspBlob(PrivateKey);
foreach (byte[] tmpKey in Message.Keys)
{
try
{
MessageKey = tmpRSA.Decrypt(tmpKey, false);
break;
}
catch
{
}
}
foreach (byte[] tmpIV in Message.IVs)
{
try
{
MessageIV = tmpRSA.Decrypt(tmpIV, false);
break;
}
catch
{
}
}
}
using (MemoryStream tmpStream = new MemoryStream(Message.Message))
{
using (TripleDESCryptoServiceProvider tmpDes = new TripleDESCryptoServiceProvider())
{
tmpDes.Key = MessageKey;
tmpDes.IV = MessageIV;
using (CryptoStream cryptStream = new CryptoStream(tmpStream, tmpDes.CreateDecryptor(), CryptoStreamMode.Read))
{
int ReadLength;
byte[] buffer = new byte[1024];
StringBuilder tmpReturn = new StringBuilder();
while ((ReadLength = cryptStream.Read(buffer, 0, buffer.Length)) != 0)
{
tmpReturn.Append(System.Text.ASCIIEncoding.ASCII.GetChars(buffer), 0, ReadLength);
}
return(tmpReturn.ToString());
}
}
}
}
public void IncomingMessage(ref Message_Private IncomingMessage, ref bool DisplayMessage)
{
//IF THERE IS A DEBUG WINDOW THEN UPDATE THE TEXT
if (DebugWindow != null)
{
DebugWindow.txtMessages.Text += string.Format("Incoming Message: {0} - {1}\n\n", IncomingMessage.TimeStamp.ToString("m/d/yy HH:mm:ss"), IncomingMessage.Message);
}
//TODO: CHECK TO SEE IF THE MESSAGE WHICH JUST CAME IN WAS A SECURITY KEY AND IF SO PARSE IT AND USE IT
if (IncomingMessage.Message.Contains("Begin Key ---->"))
{
//GET THE KEY VIA REGEX
EnabledMenu.Checked = true;
string Key = Regex.Match(IncomingMessage.Message, "Begin Key ---->(?<Key>.*)<---- End Key", RegexOptions.IgnoreCase).Groups["Key"].Value;
//ADD THE KEY TO THE LIST OF PUBLIC KEYS
if (!PublicKeys.Keys.Contains(IncomingMessage.SenderID))
{
PublicKeys.Add(IncomingMessage.SenderID, Convert.FromBase64String(Key));
}
//IF THIS MESSAGE CAME FROM US THEN JUST LET THE USER KNOW IT WORKED OTHERWISE TELL THE USER WE RECEIVED A KEY
if (IncomingMessage.SenderID != this.Connection.UserID)
{
this.EnabledMenu.Checked = true;
IncomingMessage.Message = string.Format("Public Key Received From {0}", IncomingMessage.Sender);
IncomingMessage.Sender = this.Name;
}
else
{
//LET THE USER KNOW THE KEY WAS SUCCEFULLY PLACED IN THE CONVERSATION BECAUSE WE GOT OUR MESSAGE BACK
IncomingMessage.Message = "Key sent successfully!";
IncomingMessage.Sender = this.Name;
}
}
else
{
if (EnabledMenu.Checked)
{
try
{
EncryptedWrapper tmpMessage = EncryptedWrapper.Deserialize(Convert.FromBase64String(IncomingMessage.Message));
IncomingMessage.Message = EncryptedWrapper.DecryptMessage(tmpMessage, this.MyPrivateKey);
}
catch
{
//DO NOTHING BECAUSE IT MUST BE VALID
}
}
}
}
public static EncryptedWrapper EncryptMessage(string Message, Dictionary <string, byte[]> PublicKeys)
{
using (TripleDESCryptoServiceProvider tmpDes = new TripleDESCryptoServiceProvider())
{
tmpDes.GenerateIV();
tmpDes.GenerateKey();
using (MemoryStream tmpStream = new MemoryStream())
{
using (CryptoStream cryptStream = new CryptoStream(tmpStream, tmpDes.CreateEncryptor(), CryptoStreamMode.Write))
{
cryptStream.Write(System.Text.ASCIIEncoding.ASCII.GetBytes(Message), 0, Message.Length);
cryptStream.Flush();
cryptStream.Close();
EncryptedWrapper tmpReturn = new EncryptedWrapper();
List <byte[]> encKeys = new List <byte[]>();
List <byte[]> encIVs = new List <byte[]>();
foreach (byte[] PubKey in PublicKeys.Values)
{
using (RSACryptoServiceProvider tmpRSA = new RSACryptoServiceProvider())
{
tmpRSA.ImportCspBlob(PubKey);
encKeys.Add(tmpRSA.Encrypt(tmpDes.Key, false));
encIVs.Add(tmpRSA.Encrypt(tmpDes.IV, false));
}
}
tmpReturn.IVs = encIVs.ToArray();
tmpReturn.Keys = encKeys.ToArray();
tmpReturn.Message = tmpStream.ToArray();
return(tmpReturn);
}
}
}
}
