Mqttnet: expose more information to ConnectionValidator

[liuhongbo]

not sure my request makes sense 😄

currently the MqttConnectionValidatorContext includes ClientId,Username, Password, WillMessage.

• If I want to implement a broker that can support IP whitelisting, the remote endpoint maybe good to be added to the MqttConnectionValidatorContext. IP whitelisting might be tied with ClientId or Username

• also if the client connects to broker through websocket, the reqeust url might be good to be added to MqttConnectionValidatorContext (if that is possible) . The url might contain some information as query string that will participate the authentication

Just a thought.

[JanEggers]

you should add client certificates if you just inspect message content that is not save

[chkr1011]

In general this should be possible (no matter if it makes sense or not). Since version 2.8.0 the adapters have a _Endoint_ as string defined which contains the remote IP and port.

I will check how to add this Endpoint to the validator.

Adding more information from the WebSocket channel is more complicated because it has features which are not avaialble for TCP so me must add interfaces etc.

[chkr1011]

I added the Endpoint to the validator (for the next release). Hope this helps.

[liuhongbo]

I update to version V2.8.2. Now I can access the MqttConnectionValidatorContext.Endpoint.
However, I did a test, the context.Endpoint in my test is string "0HLGFACF8503R"
I expect it would be in the format of "ip:port"
I did a simple snippet,

var a = new IPEndPoint(new IPAddress(new byte[] { 192, 168, 0, 1 }), 8000);
var s = a.ToString();

s would be "192.168.0.1:8000"
Am I missing something?
Thanks,

[liuhongbo]

After I looked at the source code, I think the reason the Endpoint is something like "0HLGFACF8503R" rather "ip:port" is because I used the ASP.NET Core 2.1 new TCP transport.
In the file MQTTnet\Source\MQTTnet.AspnetCore\MqttConnectionContext.cs

 public string Endpoint => Connection.ConnectionId;

It uses ConnectionId

Should it be something like this instead?

 public string Endpoint => (Connection as TcpConnection)._endPoint.ToString();

Of course, the _endPoint has to be changed to be public first.

[JanEggers]

TcpConnection is client side implementation of Connection.

on the server it is Microsoft.AspNetCore.Http.Connections.Internal.HttpConnectionContext.

so please create an issue at https://github.com/aspnet/KestrelHttpServer/

currently I dont see any features that expose information about the remote endpoint (https://github.com/aspnet/KestrelHttpServer/tree/release/2.2/src/Connections.Abstractions/Features)

[liuhongbo]

HttpConnectionContext add feature to expose RemoteEndPoint #2875

Will see what happen. :smiley:

Thanks,

[liuhongbo]

@halter73 suggested a solution in the issue
https://github.com/aspnet/KestrelHttpServer/issues/2875#issuecomment-418473684

IHttpConnectionFeature has the remote end point information.

the same way the HttpConnectionMiddleware does

would this work?

[JanEggers]

will try it out

[SeppPenner]

@JanEggers Do you have a status update for this?

[JanEggers]

nope

[halter73]

At this point, I'd probably just wait for ASP.NET 3.0 to do anything on this, since starting in 3.0, ConnectionContext will directly expose the RemoteEndpoint similarly to HttpContext.Connection.

[JanEggers]

thx for letting us know

[SeppPenner]

This should be fixed with https://github.com/chkr1011/MQTTnet/pull/882 (For NetCore 3.1+).