static void Main(string[] args)
{
server = new TcpListener(IPAddress.Any, 9999);
server.Start();
while (true)
{
client = server.AcceptTcpClient();
object my_lock = new object();
ns = client.GetStream();
Task.Factory.StartNew(() =>
{
// change this to change session life time
Thread.Sleep(920000);
Console.Write(DateTime.Now);
lock (my_lock)
{
Console.Write(DateTime.Now);
client.Client.Close();
}
});
Task.Factory.StartNew(() =>
{
AES aes = null;
RSACryptoServiceProvider rsa = null;
byte[] key = null;
while (true)
{
int messageType;
try
{
messageType = BitConverter.ToInt32(Receive(client, 4), 0);
}
catch (IOException e)
{
break;
}
lock (my_lock)
{
if (messageType == TCPConnection.GET_SESSION_KEY)
{
var lenBytes = BitConverter.ToInt32(Receive(client, 4), 0);
aes = GenerateSessionKey();
SendEcryptedSessionKey(aes, rsa);
}
if (messageType == TCPConnection.PUBLIC_KEY)
{
var lenBytes = BitConverter.ToInt32(Receive(client, 4), 0);
rsa = GetPublicKeyFromClient(client, lenBytes);
}
if (messageType == TCPConnection.LOGIN)
{
var lenBytes = BitConverter.ToInt32(Receive(client, 4), 0);
var msg = Receive(client, lenBytes);
byte[] loginLenArray = new byte[4];
Array.Copy(msg, 0, loginLenArray, 0, 4);
var loginLen = BitConverter.ToInt32(loginLenArray, 0);
byte[] loginArray = new byte[loginLen];
Array.Copy(msg, 4, loginArray, 0, loginLen);
loginArray = AES.Decrypt(loginArray, aes.rijndaelManaged.Key, aes.rijndaelManaged.IV);
var login = Encoding.Default.GetString(loginArray);
var passwordLen = msg.Length - 4 - loginLen;
byte[] passwordArray = new byte[passwordLen];
Array.Copy(msg, 4 + loginLen, passwordArray, 0, passwordLen);
passwordArray = AES.Decrypt(passwordArray, aes.rijndaelManaged.Key, aes.rijndaelManaged.IV);
var password = Encoding.Default.GetString(passwordArray);
if (checkUser(login, password))
{
if (key == null)
{
key = KeyGeneration.GenerateRandomKey(20);
Send(client, TCPConnection.QR_CODE_GENERATED, AES.Encrypt(key, aes.rijndaelManaged.Key, aes.rijndaelManaged.IV));
}
else
{
Send(client, TCPConnection.USE_OLD_KEY, null);
}
}
else
{
Send(client, TCPConnection.LOGIN_REJECTED, null);
}
}
else if (messageType == TCPConnection.FILENAME)
{
var lenBytes = BitConverter.ToInt32(Receive(client, 4), 0);
var msg = Receive(client, lenBytes);
var filename = Encoding.UTF8.GetString(AES.Decrypt(msg, aes.rijndaelManaged.Key, aes.rijndaelManaged.IV));
if (File.Exists(filename))
{
var text = File.ReadAllBytes(filename);
text = AES.Encrypt(text, aes.rijndaelManaged.Key, aes.rijndaelManaged.IV);
Send(client, TCPConnection.TEXT, text);
}
else
{
Send(client, TCPConnection.FILE_DO_NOT_EXISTS, null);
}
}
else if (messageType == TCPConnection.TEXT)
{
var lenBytes = BitConverter.ToInt32(Receive(client, 4), 0);
var msg = Receive(client, lenBytes);
byte[] filenameLenArray = new byte[4];
Array.Copy(msg, 0, filenameLenArray, 0, 4);
var filenameLen = BitConverter.ToInt32(filenameLenArray, 0);
byte[] filenameArray = new byte[filenameLen];
Array.Copy(msg, 4, filenameArray, 0, filenameLen);
filenameArray = AES.Decrypt(filenameArray, aes.rijndaelManaged.Key, aes.rijndaelManaged.IV);
var filename = Encoding.Default.GetString(filenameArray);
var textLen = msg.Length - 4 - filenameLen;
byte[] textArray = new byte[textLen];
Array.Copy(msg, 4 + filenameLen, textArray, 0, textLen);
textArray = AES.Decrypt(textArray, aes.rijndaelManaged.Key, aes.rijndaelManaged.IV);
File.WriteAllBytes(filename, textArray);
Send(client, TCPConnection.FILE_SAVED, null);
}
else if (messageType == TCPConnection.QR_PASS_FROM_USER)
{
var lenBytes = BitConverter.ToInt32(Receive(client, 4), 0);
var msg = Receive(client, lenBytes);
byte[] qrPassArray = new byte[lenBytes];
Array.Copy(msg, 0, qrPassArray, 0, lenBytes);
var decrypred = AES.Decrypt(qrPassArray, aes.rijndaelManaged.Key, aes.rijndaelManaged.IV);
var pass = Encoding.Default.GetString(decrypred);
var totp = new Totp(key);
var isValidTotpCode = totp.VerifyTotp(DateTime.UtcNow, pass, out long timeStepMatched, new VerificationWindow(previous: 1, future: 1));
Send(client, TCPConnection.LOGIN_APPROVED, null);
}
}
}
});
}
}
private void btnMainAct_Click(object sender, EventArgs e)
{
if (_connectionState == false)
{
string ip = ipTextBox.Text;
string portStr = portTextBox.Text;
ip = ipCheck(ip);
int port = portCheck(portStr);
if (ip == "" || port == -1)
{
return;
}
_server = new AsyncServer(ip, port, AddLog, new Command[] {
new Command("hello", (state, parts) =>
{
return($"hello variant {parts[1]}");
}),
new Command("bye", true, (state, parts) =>
{
if (parts.Length == 1)
{
return("bye");
}
return($"bye variant {parts[1]}");
}),
new Command("encrypt", (state, parts) =>
{
string pass = "";
string text = "";
bool isFile = false;
for (int i = 1; i < parts.Length; ++i)
{
if (parts[i] == "-f")
{
isFile = true;
}
else if (parts[i] == "-p")
{
if (i + 1 == parts.Length)
{
return("Wrong cmd: use encrypt [-p] <pass> <message>");
}
else
{
pass = parts[i + 1];
++i;
}
}
else if (pass != "")
{
StringBuilder sb = new StringBuilder();
for (int j = i; j < parts.Length; ++j)
{
sb.Append(parts[j]);
}
text = sb.ToString();
break;
}
}
if (pass != "" && text != "")
{
MD5Hash hasher = new MD5Hash();
pass = hasher.GetHash(pass, true);
AES aes = new AES();
text = aes.Encrypt(text, pass, !isFile);
return(text);
}
else
{
return("Wrong cmd: use encrypt [-p] <pass> <message>");
}
}),
new Command("decrypt", (state, parts) =>
{
string pass = "";
string text = "";
bool isFile = false;
for (int i = 1; i < parts.Length; ++i)
{
if (parts[i] == "-f")
{
isFile = true;
}
else if (parts[i] == "-p")
{
if (i + 1 == parts.Length)
{
return("Wrong cmd: use encrypt [-p] <pass> <message>");
}
else
{
pass = parts[i + 1];
++i;
}
}
else if (pass != "")
{
StringBuilder sb = new StringBuilder();
for (int j = i; j < parts.Length; ++j)
{
sb.Append(parts[j]);
}
text = sb.ToString();
break;
}
}
if (pass != "" && text != "")
{
MD5Hash hasher = new MD5Hash();
pass = hasher.GetHash(pass, true);
AES aes = new AES();
text = aes.Decrypt(text, pass);
return(text);
}
else
{
return("Wrong cmd: use encrypt [-p] <pass> <message>");
}
}),
new Command("help", (state, parts) =>
{
string help = "hello <n>, bye <n>, [encrypt | decrypt] -p <pass> <text>";
return(help);
}),
});
_token = new CancellationTokenSource();
CancellationToken ct = _token.Token;
_task = new Task(() =>
{
_server.Start(ct);
}, ct);
_task.Start();
btnMainAct.Text = "Деактивировать";
_connectionState = true;
}
else
{
AsyncServer.AllDone.Set();
_token.Cancel();
Task.Factory.StartNew(() =>
{
_server.Stop();
});
btnMainAct.Text = "Активировать";
_connectionState = false;
}
}
static void Main(string[] args)
{
server = new TcpListener(IPAddress.Any, 9999);
server.Start();
while (true)
{
client = server.AcceptTcpClient();
object my_lock = new object();
ns = client.GetStream();
Task.Factory.StartNew(() =>
{
Thread.Sleep(10000);
Console.Write(DateTime.Now);
lock (my_lock)
{
Console.Write(DateTime.Now);
client.Client.Close();
}
});
Task.Factory.StartNew(() =>
{
AES aes = null;
RSACryptoServiceProvider rsa = null;
while (true)
{
int messageType;
try
{
messageType = BitConverter.ToInt32(Receive(client, 4), 0);
}
catch (IOException e)
{
break;
}
lock (my_lock)
{
if (messageType == TCPConnection.GET_SESSION_KEY)
{
var lenBytes = BitConverter.ToInt32(Receive(client, 4), 0);
aes = GenerateSessionKey();
SendEcryptedSessionKey(aes, rsa);
}
if (messageType == TCPConnection.PUBLIC_KEY)
{
var lenBytes = BitConverter.ToInt32(Receive(client, 4), 0);
rsa = GetPublicKeyFromClient(client, lenBytes);
}
if (messageType == TCPConnection.LOGIN)
{
var lenBytes = BitConverter.ToInt32(Receive(client, 4), 0);
var msg = Receive(client, lenBytes);
byte[] loginLenArray = new byte[4];
Array.Copy(msg, 0, loginLenArray, 0, 4);
var loginLen = BitConverter.ToInt32(loginLenArray, 0);
byte[] loginArray = new byte[loginLen];
Array.Copy(msg, 4, loginArray, 0, loginLen);
loginArray = AES.Decrypt(loginArray, aes.rijndaelManaged.Key, aes.rijndaelManaged.IV);
var login = Encoding.Default.GetString(loginArray);
var passwordLen = msg.Length - 4 - loginLen;
byte[] passwordArray = new byte[passwordLen];
Array.Copy(msg, 4 + loginLen, passwordArray, 0, passwordLen);
passwordArray = AES.Decrypt(passwordArray, aes.rijndaelManaged.Key, aes.rijndaelManaged.IV);
var password = Encoding.Default.GetString(passwordArray);
if (checkUser(login, password))
{
Send(client, TCPConnection.LOGIN_APPROVED, null);
}
else
{
Send(client, TCPConnection.LOGIN_REJECTED, null);
}
}
else if (messageType == TCPConnection.FILENAME)
{
var lenBytes = BitConverter.ToInt32(Receive(client, 4), 0);
var msg = Receive(client, lenBytes);
var filename = Encoding.UTF8.GetString(AES.Decrypt(msg, aes.rijndaelManaged.Key, aes.rijndaelManaged.IV));
if (File.Exists(filename))
{
var text = File.ReadAllBytes(filename);
text = AES.Encrypt(text, aes.rijndaelManaged.Key, aes.rijndaelManaged.IV);
Send(client, TCPConnection.TEXT, text);
}
else
{
Send(client, TCPConnection.FILE_DO_NOT_EXISTS, null);
}
}
else if (messageType == TCPConnection.TEXT)
{
var lenBytes = BitConverter.ToInt32(Receive(client, 4), 0);
var msg = Receive(client, lenBytes);
byte[] filenameLenArray = new byte[4];
Array.Copy(msg, 0, filenameLenArray, 0, 4);
var filenameLen = BitConverter.ToInt32(filenameLenArray, 0);
byte[] filenameArray = new byte[filenameLen];
Array.Copy(msg, 4, filenameArray, 0, filenameLen);
filenameArray = AES.Decrypt(filenameArray, aes.rijndaelManaged.Key, aes.rijndaelManaged.IV);
var filename = Encoding.Default.GetString(filenameArray);
var textLen = msg.Length - 4 - filenameLen;
byte[] textArray = new byte[textLen];
Array.Copy(msg, 4 + filenameLen, textArray, 0, textLen);
textArray = AES.Decrypt(textArray, aes.rijndaelManaged.Key, aes.rijndaelManaged.IV);
File.WriteAllBytes(filename, textArray);
Send(client, TCPConnection.FILE_SAVED, null);
}
}
}
});
}
}