/// <summary>
/// Handles socket client request - encrypts or decrypts text
/// </summary>
/// <param name="client">client to handle</param>
private static void HandleClient(Socket client)
{
Console.WriteLine(String.Format("Client connected. Task: {0}", Task.CurrentId.HasValue ? Task.CurrentId.Value.ToString() : "-"));
//recieve data
byte[] data = new byte[1024 * 5000];
int receivedBytesLen = client.Receive(data);
byte[] receivedData = new byte[receivedBytesLen];
Array.Copy(data, receivedData, receivedBytesLen);
//deserialize data
SDO sdoEncoder = new SDO();
Message receivedMessage = (Message)sdoEncoder.Deserialize(receivedData, typeof(Message));
Console.WriteLine(String.Format("Original message text: {0}. Task: {1}", receivedMessage.Text, Task.CurrentId.HasValue ? Task.CurrentId.Value.ToString() : "-"));
//select crypto algorithm
SymmetricAlgorithm cryptAlgorithm;
switch (receivedMessage.Alg)
{
case "Rijndael":
cryptAlgorithm = Rijndael.Create();
break;
case "TripleDES":
cryptAlgorithm = TripleDES.Create();
break;
default: goto case "Rijndael";
}
//parse key and initialization vecor
byte[] key = new byte[16];
byte[] iv = new byte[16];
byte[] receivedKey = Encoding.UTF8.GetBytes(receivedMessage.Key);
byte[] receivedIV = Encoding.UTF8.GetBytes(receivedMessage.IV);
Array.Copy(receivedKey, key, receivedKey.Length);
Array.Copy(receivedIV, iv, receivedIV.Length);
//encrypt or decrypt text
string proccessedText;
if (receivedMessage.Encrypt)
proccessedText = Encrypt(receivedMessage.Text, key, iv, cryptAlgorithm);
else
proccessedText = Decrypt(receivedMessage.Text, key, iv, cryptAlgorithm);
Console.WriteLine(String.Format("Proccessed message text: {0}. Task: {1}", proccessedText, Task.CurrentId.HasValue ? Task.CurrentId.Value.ToString() : "-"));
//serialize and send proccessed text back to client
byte[] serializedText = sdoEncoder.Serialize(proccessedText);
client.Send(serializedText);
//close connection
client.Close();
Console.WriteLine(String.Format("Client disconnected. Task: {0}", Task.CurrentId.HasValue ? Task.CurrentId.Value.ToString() : "-"));
}
static void Main(string[] args)
{
bool correctUserInput = false;
string text = "";
string fileName = "";
while (!correctUserInput)
{
//get file name
Console.WriteLine("Įveskite duomenų failo pavadinimą:");
fileName = Console.ReadLine();
//read file
try
{
FileStream fs = File.Open(fileName, FileMode.Open, FileAccess.Read, FileShare.None);
byte[] bytesRead = new byte[fs.Length];
int numBytesToRead = (int)fs.Length;
int numBytesRead = 0;
while (numBytesToRead > 0)
{
// read may return anything from 0 to numBytesToRead.
int n = fs.Read(bytesRead, numBytesRead, numBytesToRead);
// break when the end of the file is reached.
if (n == 0)
break;
numBytesRead += n;
numBytesToRead -= n;
}
text = Encoding.UTF8.GetString(bytesRead);
correctUserInput = true;
}
catch (Exception e) { Console.WriteLine(String.Format("Nepavyko nuskaityti failo: {0}. Bandykite dar kartą.", e.Message)); correctUserInput = false; };
}
//encrypt or decrypt
correctUserInput = false;
bool encrypt = false;
while (!correctUserInput)
{
Console.WriteLine("Tekstas turi būti užšifruotas ar iššifruotas? \n 1 - Užšifruotas \n 2 - Iššifruotas");
try
{
int chosenAlg = int.Parse(Console.ReadLine());
switch (chosenAlg)
{
case 1: encrypt = true;
correctUserInput = true;
break;
case 2: encrypt = false;
correctUserInput = true;
break;
}
}
catch (Exception e) { Console.WriteLine("Neteisingai pasirinktas variantas. Bandykite dar kartą."); }
}
//choose Crypto algorithm
correctUserInput = false;
string algorithmName = "";
while (!correctUserInput)
{
Console.WriteLine("Pasirinkite šifravimo algoritmą: \n 1 - Rijndael \n 2 - TripleDES");
try
{
int chosenAlg = int.Parse(Console.ReadLine());
switch (chosenAlg)
{
case 1: algorithmName = "Rijndael";
correctUserInput = true;
break;
case 2: algorithmName = "TripleDES";
correctUserInput = true;
break;
}
}
catch (Exception e){ Console.WriteLine("Neteisingai pasirinktas šiframvimo algoritmas. Bandykite dar kartą."); }
}
//get Key
correctUserInput = false;
string key = "";
while(!correctUserInput)
{
Console.WriteLine("Įveskite šifravmimo raktą:");
key = Console.ReadLine();
if (key.Length <= 16)
correctUserInput = true;
else
Console.WriteLine("Raktas negali būti ilgesnis nei 16 simbolių. Bandykite dar kartą.");
}
//get initializacion vector
string iv;
if (encrypt)
{
iv = RandomString(5);
Console.WriteLine(String.Format("Jums sugeneruotas inicializacijos vektorius:{0}", iv));
}
else
{
Console.WriteLine("Įveskite inicializacijos vektorių:");
iv = Console.ReadLine();
}
Message msg = new Message() { Alg = algorithmName, IV = iv, Key = key, Text = text, Encrypt = encrypt };
SDO sdoEncoder = new SDO();
byte[] serializedMessage = sdoEncoder.Serialize(msg);
//connect to server
IPAddress ipAddress = IPAddress.Loopback;//Dns.GetHostAddresses("localhost")[0];
IPEndPoint ipEnd = new IPEndPoint(ipAddress, 5656);
Socket clientSock = new Socket(ipAddress.AddressFamily, SocketType.Stream, ProtocolType.IP);
clientSock.Connect(ipEnd);
//send serialized message
clientSock.Send(serializedMessage);
//get response
byte[] data = new byte[1024 * 5000];
int receivedBytesLen = clientSock.Receive(data);
byte[] receivedData = new byte[receivedBytesLen];
Array.Copy(data, receivedData, receivedBytesLen);
//close connection
clientSock.Close();
string receivedText = (string)sdoEncoder.Deserialize(receivedData, typeof(string));
//save encrypted/decrypted info to file
fileName = fileName.Substring(0,fileName.IndexOf('.')) + "Response.txt";
File.WriteAllText(fileName, receivedText);
Console.WriteLine(String.Format("Užšifruotas/iššifruotas tekstas buvo išsaugotas į failą: {0}", fileName));
Console.ReadKey();
}
