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PskTlsClient with Bouncy castle, System.IO.IOException on Connect

I'm developing a client-server with psk by openssl.
At the moment the server side is not implemented yet, there is a stub on my Ubuntu Linux machine only for tests purpose as the following:
openssl s_server -accept 9999 -cipher ECDHE-PSK-CHACHA20-POLY1305 -nocert -psk 6161616161 -psk_identity admin
There are some problems on the client side, I'm stuck in a rut because everything seems implemented as the following
class Program
{
private static readonly SecureRandom _secureRandom = new SecureRandom();
internal static TlsClientProtocol OpenTlsConnection(string hostname, int port, Org.BouncyCastle.Crypto.Tls.TlsClient client)
{
var tcp = new TcpClient(hostname, port);
var protocol = new TlsClientProtocol(tcp.GetStream(), _secureRandom);
protocol.Connect(client);
return protocol;
}
static void Main(string[] args)
{
var hostname = "192.168.132.160";
var port = 9999;
var psk_identity = "admin";
// hardcoded psk
var psk = new byte[] { 0x61, 0x61, 0x61, 0x61, 0x61 };
var pskIdentity = new BasicTlsPskIdentity(psk_identity, psk);
var client = new PskTlsClient(null, pskIdentity);
var protocol = OpenTlsConnection(hostname, port, client);
// Tryng to send something
var req = Encoding.UTF8.GetBytes("GET / HTTP/1.1\r\n\r\n");
var tlsStream = protocol.Stream;
tlsStream.Write(req, 0, req.Length);
tlsStream.Flush();
var reader = new StreamReader(tlsStream);
string line;
while ((line = reader.ReadLine()) != null)
{
Console.WriteLine(">>> " + line);
}
protocol.Close();
}
}
I get this exception every time:
System.IO.IOException: 'Unable to read data from the transport
connection: A connection attempt failed because the connected party
did not properly respond after a period of time, or established
connection failed because connected host has failed to respond.'
In addition, this code on my Linux Machine works
openssl s_client -connect 192.168.132.160:9999 -psk 6161616161 -psk_identity admin -tls1_2
Did I miss something on my client side? Can anyone help me? I'm going mad.
Thanks

PskTlsClient only provides some cipher by default, to add what I wanted I develop a little proxy (design pattern) of PskTlsClient overriding GetCipherSuites() as the following:
public class PskTlsClientProxy : PskTlsClient
{
public PskTlsClientProxy(TlsPskIdentity pskIdentity) : base(pskIdentity)
{
}
public PskTlsClientProxy(TlsCipherFactory cipherFactory, TlsPskIdentity pskIdentity) : base(cipherFactory, pskIdentity)
{
}
public PskTlsClientProxy(TlsCipherFactory cipherFactory, TlsDHVerifier dhVerifier, TlsPskIdentity pskIdentity) : base(cipherFactory, dhVerifier, pskIdentity)
{
}
public override void NotifyServerVersion(ProtocolVersion serverVersion)
{
base.NotifyServerVersion(serverVersion);
Console.WriteLine("TLS-PSK client negotiated " + serverVersion);
}
public override int[] GetCipherSuites()
{
return new int[] {
CipherSuite.DRAFT_TLS_ECDHE_PSK_WITH_CHACHA20_POLY1305_SHA256,
};
}
}

M2MQTT client disconnecting without an exception or error message

I'm trying to create an API that consumes various topics.
For this, I'm trying to multi-thread things, so that the whole thing can be scalable into multiple APIs, later on, but that's very besides the point.
I'm using ASP.net Core 4.0, if that's got anything to do with it. Entity Framework as well.
My problem is based on my connection to my Mosquitto server being broken without throwing an exception or anything of the like, after a minute or so. It doesn't matter how big the messages are, or how many are exchanged. I have no idea of how I can create a callback or anything of the kind to know what's going on with my connection. Can anyone help?
I'll link the code I use to establish a connection and subscribe to a connection below. Using the Subscribe method or doing it manually also changes nothing. I'm at a loss, here.
Thanks in advance!
Main.cs:
Task.Factory.StartNew(() => DataflowController.ResumeQueuesAsync());
BuildWebHost(args).Run();
DataflowController.cs:
public static Boolean Subscribe(String topic)
{
Console.WriteLine("Hello from " + topic);
MqttClient mqttClient = new MqttClient(brokerAddress);
byte code = mqttClient.Connect(Guid.NewGuid().ToString());
// Register to message received
mqttClient.MqttMsgPublishReceived += client_recievedMessageAsync;
string clientId = Guid.NewGuid().ToString();
mqttClient.Connect(clientId);
// Subscribe to topic
mqttClient.Subscribe(new String[] { topic }, new byte[] { MqttMsgBase.QOS_LEVEL_EXACTLY_ONCE });
System.Console.ReadLine();
return true;
}
public static async Task ResumeQueuesAsync()
{
var mongoClient = new MongoClient(connectionString);
var db = mongoClient.GetDatabase(databaseName);
var topics = db.GetCollection<BsonDocument>(topicCollection);
var filter = new BsonDocument();
List<BsonDocument> result = topics.Find(filter).ToList();
var resultSize = result.Count;
Task[] subscriptions = new Task[resultSize];
MqttClient mqttClient = new MqttClient(brokerAddress);
byte code = mqttClient.Connect(Guid.NewGuid().ToString());
// Register to message received
mqttClient.MqttMsgPublishReceived += client_recievedMessageAsync;
string clientId = Guid.NewGuid().ToString();
mqttClient.Connect(clientId);
int counter = 0;
foreach(var doc in result)
{
subscriptions[counter] = new Task(() =>
{
Console.WriteLine("Hello from " + doc["topic"].ToString());
// Subscribe to topic
mqttClient.Subscribe(new String[] { doc["topic"].ToString() }, new byte[] { MqttMsgBase.QOS_LEVEL_EXACTLY_ONCE });
System.Console.ReadLine();
});
counter++;
}
foreach(Task task in subscriptions)
{
task.Start();
}
}
static async void client_recievedMessageAsync(object sender, MqttMsgPublishEventArgs e)
{
// Handle message received
var message = System.Text.Encoding.Default.GetString(e.Message);
var topic = e.Topic;
var id = topic.Split("/")[2];
BsonDocument doc = new BsonDocument {
{"Plug ID", id },
{"Consumption", message }
};
await Save(doc, "smartPDM_consumption");
System.Console.WriteLine("Message received from " + topic + " : " + message);
}

This line was the issue:
byte code = mqttClient.Connect(Guid.NewGuid().ToString());
Deleted it, and it just worked.

Custom Transport Agent - holding email in mailbox

I am developing a custom transport agent in C#.I am using microsoft exhange server 2010 for this. Whenever an emails comes i need to decide if it should allow to go or not on the basis of some condition. If it should not be allowed to go i store whole email(.eml) as blob in database.Now i want not to use database for holding rejected emails. i want to hold those emails in some mailbox. I want to know if it is possible to redirect an email to mailbox?

public class FIMFactory : RoutingAgentFactory
{
public override RoutingAgent CreateAgent(SmtpServer server)
{
return new FIMAgent(server);
}
}
public class FIMAgent : RoutingAgent
{
private readonly SmtpServer _server;
public FIMAgent(SmtpServer server)
{
_server = server ?? throw new ArgumentNullException(nameof(server));
OnResolvedMessage += FIMAgent_OnResolvedMessage;
}
private void FIMAgent_OnResolvedMessage(ResolvedMessageEventSource source, QueuedMessageEventArgs e)
{
var mi = e.MailItem;
var emailMessage = EmailMessage.Create(BodyFormat.Text, false, "utf-8");
emailMessage.Sender = new EmailRecipient(mi.Message.Sender.DisplayName, mi.Message.Sender.SmtpAddress);
emailMessage.To.Add(new EmailRecipient(mi.Message.Sender.DisplayName, mi.Message.Sender.SmtpAddress));
emailMessage.Subject = "...";
using (var stream1 = emailMessage.Body.GetContentWriteStream())
using (var sw = new StreamWriter(stream1, new UTF8Encoding(false)))
{
sw.WriteLine("...");
}
_server.SubmitMessage(emailMessage);
}
}

SSH terminal in a webapp using ASP.NET

Hello I creating a webapp that has a working SSH terminal similar to Putty. I'm using SSH Library as a means of handling the ssh stream. However there is a problem. I can log into a Cisco 2950 and type in commands but it comes out jumbled and in one line.
Also when I try "conf t" it gets into the configuration terminal but then you can't do anything and this pops up "Line has invalid autocommand "?".
Here is the code I have so far:
This is the SSH.cs that interacts with the library.
public class SSH
{
public string cmdInput { get; set; }
public string SSHConnect()
{
var PasswordConnection = new PasswordAuthenticationMethod("username", "password");
var KeyboardInteractive = new KeyboardInteractiveAuthenticationMethod("username");
// jmccarthy is the username
var connectionInfo = new ConnectionInfo("10.56.1.2", 22, "username", PasswordConnection, KeyboardInteractive);
var ssh = new SshClient(connectionInfo);
ssh.Connect();
var cmd = ssh.CreateCommand(cmdInput);
var asynch = cmd.BeginExecute(delegate(IAsyncResult ar)
{
//Console.WriteLine("Finished.");
}, null);
var reader = new StreamReader(cmd.OutputStream);
var myData = "";
while (!asynch.IsCompleted)
{
var result = reader.ReadToEnd();
if (string.IsNullOrEmpty(result))
continue;
myData = result;
}
cmd.EndExecute(asynch);
return myData;
}
}
This the code in the .aspx.cs that displays the code on the web page.
protected void CMD(object sender, EventArgs e)
{
SSH s = new SSH();
s.cmdInput = input.Text;
output.Text = s.SSHConnect();
}
Any help would be appreciated.

From looking through the test cases in the code for the SSH.NET library, you can use the RunCommand method instead of CreateCommand, which will synchronously process the command. I also added a using block for the SshClient ssh object since it implements iDisposable. Remember to call Disconnect as well so you don't get stuck with open connections.
Also the SshCommand.Result property (used in the command.Result call below), encapsulates the logic to pull the results from the OutputSteam, and uses this._session.ConnectionInfo.Encoding to read the OutputStream using the proper encoding. This should help with the jumbled lines you were receiving.
Here is an example:
public string SSHConnect() {
var PasswordConnection = new PasswordAuthenticationMethod("username", "password");
var KeyboardInteractive = new KeyboardInteractiveAuthenticationMethod("username");
string myData = null;
var connectionInfo = new ConnectionInfo("10.56.1.2", 22, "username", PasswordConnection, KeyboardInteractive);
using (SshClient ssh = new SshClient(connectionInfo)){
ssh.Connect();
var command = ssh.RunCommand(cmdInput);
myData = command.Result;
ssh.Disconnect();
}
return myData;
}

How do I implement a C# Thrift service and consume it with a Silverlight client?

I'm current looking at Thrift to use as a RPC framework for our apps (mostly written in C# and Silverlight). I've come as far as implementing a service and consuming it from a C# console app (using a socket as transport).
For the C# server side code my code looked like: (basically copying the tutorials included with the source code)
MyServiceHandler handler = new MyServiceHandler();
MyService.Processor processor = new MyService.Processor(handler);
TServerTransport serverTransport = new TServerSocket(9090);
TServer server = new TSimpleServer(processor, serverTransport);
server.Serve();
For the client side code it looked like:
TTransport transport = new TSocket("localhost", 9090);
TProtocol protocol = new TBinaryProtocol(transport);
MyService.Client client = new MyService.Client(protocol);
transport.Open();
client.SomeServiceCall();
However, we will be consuming the service from a Silverlight client, and unfortunately there is no support for sockets in Silverlight for Thrift. I assume I'm forced to use HTTP communication between the client and service, using Thrift's C# THttpClient and THttpHandler classes? I could not find any examples of how to do this out there, can anyone point me in the right direction? Some example server and client side code would be appreciated.

It seems that this issue was already addressed by this guy. According to this JIRA, the fix is available in Thrift 0.9. You can either try this snapshot (note that, as it's not a final release, it might not be stable) or you can apply this patch to the 0.8 release.

I believe by now you would have understood, there is no direct way of communicating from Silverlight to the Cassandra database either using Thrift or any other clients.
I have one simple option related to this. Write a Silverlight enabled web service and consume it from the client.
For example, on the server side you can have a web service which does insert/update/read etc., like this. I just managed to pull out some code which we use for our project. Hope this helps.
using Apache.Cassandra;
using Thrift.Protocol;
using Thrift.Transport;
namespace CassandraWebLibrary
{
public class MyDb
{
String _host;
int _port;
String _keyspace;
bool _isConnected;
TTransport _transport = null;
Apache.Cassandra.Cassandra.Client _client = null;
String columnFamily = "ColumnFamilyName";
public VazhikaattiDB(String host, int port, String keyspace)
{
_host = host;
_port = port;
_keyspace = keyspace;
_isConnected = false;
}
public bool Connect()
{
try
{
_transport = new TFramedTransport(new TSocket(_host, _port));
TProtocol protocol = new TBinaryProtocol(_transport);
_client = new Apache.Cassandra.Cassandra.Client(protocol);
_transport.Open();
_client.set_keyspace(_keyspace);
_isConnected = true;
}
catch (Exception ex)
{
log.Error(ex.ToString());
}
return _isConnected;
}
public bool Close()
{
if (_transport.IsOpen)
_transport.Close();
_isConnected = false;
return true;
}
public bool InsertData(Send your data as parameters here)
{
try
{
List<Column> list = new List<Column>();
string strKey = keyvalue;
#region Inserting into Coulmn family
List<Byte> valbytes = new List<byte>(BitConverter.GetBytes(value)); //You might have to pad this with more bytes to make it length of 8 bytes
Column doublecolumn1 = new Column()
{
Name = Encoding.UTF8.GetBytes("column1"),
Timestamp = timestampvalue,
Value = valbytes.ToArray()
};
list.Add(doublecolumn1);
Column stringcolumn2 = new Column()
{
Name = Encoding.UTF8.GetBytes("column2"),
Timestamp = timestampvalue,
Value = Encoding.UTF8.GetBytes("StringValue")
};
list.Add(stringcolumn2);
Column timecolumn3 = new Column()
{
Name = Encoding.UTF8.GetBytes("column3"),
Timestamp = timestampvalue,
Value = BitConverter.GetBytes(DateTime.Now.Ticks)
};
list.Add(timecolumn3);
#endregion
ColumnParent columnParent = new ColumnParent();
columnParent.Column_family = columnFamily;
Byte[] key = Encoding.UTF8.GetBytes(strKey);
foreach (Column column in list)
{
try
{
_client.insert(key, columnParent, column, ConsistencyLevel.QUORUM);
}
catch (Exception e)
{
log.Error(e.ToString());
}
}
return true;
}
catch (Exception ex)
{
log.Error(ex.ToString());
return false;
}
}
public List<YourReturnObject> GetData(parameters)
{
try
{
ColumnParent columnParent = new ColumnParent();
columnParent.Column_family = columnFamily;
DateTime curdate = startdate;
IndexExpression indExprsecondkey = new IndexExpression();
indExprsecondkey.Column_name = Encoding.UTF8.GetBytes("column");
indExprsecondkey.Op = IndexOperator.EQ;
List<Byte> valbytes = PadLeftBytes((int)yourid, 8);
indExprsecondkey.Value = valbytes.ToArray();
indExprList.Add(indExprsecondkey);
IndexClause indClause = new IndexClause()
{
Expressions = indExprList,
Count = 1000,
Start_key = Encoding.UTF8.GetBytes("")
};
SlicePredicate slice = new SlicePredicate()
{
Slice_range = new SliceRange()
{
//Start and Finish cannot be null
Start = new byte[0],
Finish = new byte[0],
Count = 1000,
Reversed = false
}
};
List<KeySlice> keyslices = _client.get_indexed_slices(columnParent, indClause, slice, ConsistencyLevel.ONE);
foreach (KeySlice ks in keyslices)
{
String stringcolumnvalue = Encoding.UTF8.GetString(cl.Column.Value);
double doublevalue= (Double)BitConverter.ToDouble(cl.Column.Value);
long timeticks = BitConverter.ToInt64(cl.Column.Value, 0);
DateTime dtcolumntime = new DateTime(timeticks);
}
}
catch (Exception ex)
{
log.Error(ex.ToString());
}
return yourdatalist;
}
}
}
Now the above class can be used by your webservice, which in turn will be used by Silverlight. Btw, you'll have to take care of other silverlight issues like size of data to be downloaded from server/webservice etc.,
FYI, our client service of Cassandra runs on port 9160..