/// <summary>
/// Encryptes the given data and sends it as a packet to the receiver
/// </summary>
/// <param name="data">The raw bytes that shall be send</param>
/// <exception cref="IOException">If anything went wrong with the I/O</exception>
public void SendPacket(params byte[] data)
{
try
{
// Encryptes the data using the received key
byte[] encrypted = SimpleSecurityUtils.EncryptAES(data, this.aesKey, this.aesIv);
// Checks if anything failed with the encryption
if (encrypted == null)
{
throw new Exception("Encryption failed");
}
// Sends the length of the packet
this.stream.WriteByte((byte)encrypted.Length);
this.stream.WriteByte((byte)(encrypted.Length >> 8));
// Sends the actual encrypted data
this.stream.Write(encrypted, 0, encrypted.Length);
this.stream.Flush();
}
catch (Exception e)
{
// Converts any exception to an i/o-exception
throw new IOException(e.Message);
}
}
/// <summary>
/// Saves the config file encrypted using the passed key
/// </summary>
/// <param name="filePath">The path to the file where to save the configuration</param>
/// <param name="key">The key for encrypting the file</param>
/// <exception cref="ConfigException">Something went wrong while encryption (Unknown)</exception>
/// <exception cref="Exception">All exception that can be passed on by File.WriteAllBytes called with the filePath</exception>
public void SaveConfig(string filePath, string key)
{
// Generates the object that will be saved as the config file
JObject json = new JObject()
{
["port"] = this.Port,
["host"] = this.Host,
["rsa"] = SimpleSecurityUtils.SaveRSAToJson(this.PrivateKey)
};
// Generates the actual key and iv from the previous plain text key
byte[] aesKey = SimpleSecurityUtils.HashSHA256(Encoding.UTF8.GetBytes(key));
byte[] aesIv = SimpleSecurityUtils.HashMD5(Encoding.UTF8.GetBytes(key));
// Encryptes the config-json object
byte[] encData = SimpleSecurityUtils.EncryptAES(Encoding.UTF8.GetBytes(json.ToString()), aesKey, aesIv);
// Checks if the encryption failed
if (encData == null)
{
// Unknown exception
throw new ConfigException();
}
// Writes all data to the file
File.WriteAllBytes(filePath, encData);
}