Identify network devices

[LemonParty]

I need a simple web server that also can output JSON answers. I also need a login system that can memorize connected before devices.

The question is how to organize the login system. What should I store on server-side to identify connected devices properly?

Maybe someone has a ready template for such server. That would be very nice if you share it.

[Thaddy]

You store a hash, not the credentials.
This has been answered umpty times.
You can *and should* avoid session cookies by simply storing IP and browser string. That is the correct way.

If you need cookies...... especially the "legitimate interest" ones..... you are on a wrong path.
That will be gone within months.(Finally)

[LemonParty]

storing IP and browser string

Could you show how to get that in code?

IP can be in two versions v4 and v6. Which one will be returned?

[LeP]

You should have something in FPC web ecosystem that get "USER-AGENT" and "REMOTEIP" from http header (that are strings).

So, maintain Hash of those is not a problem (you don't need to know if it's IPv6 or IPv4).

Be carefull that "USER-AGENT" contains very common datas and REMOTEIP doesn't securely identify a machine.

So this can be used in a local network where IP adress are normally assigned statically or with long lease, and for a short time.

The use of MAC ADDRESS is a better choice instead of IP in a local lan.

[dbannon]

If you are using the (really good) fpc http client and server, this will help -

Firstly, you need to override the function that gets called when a request is made, eg -

Code: Pascal  [Select][+][-]

1. TMistyHTTPServer = Class(TFPHTTPServer)  
2.     ...
3.     procedure HandleRequest(Var ARequest: TFPHTTPConnectionRequest;
4.                             Var AResponse : TFPHTTPConnectionResponse); override;

Then implement that function

Code: Pascal  [Select][+][-]

1. procedure TMistyHTTPServer.HandleRequest(var ARequest: TFPHTTPConnectionRequest;
2.                                         var AResponse: TFPHTTPConnectionResponse);
3. ...
4.     IP := ARequest.RemoteAddress;

Both ARequest and AResponse have lots of info in there, sadly not documented but look in the source ....

Remember IP addresses are reassignable, one machine may have a particular IP today but sure does not mean its the same tomorrow.

Are you connecting as a web service where you have control of the client ?  Better to send a unique code rather than relying on IP.

Davo

[LemonParty]

Where I can download OpenSSL libraries needed for work of SSL?

[LemonParty]

I found https://kb.firedaemon.com/support/solutions/articles/4000121705
This version OpenSSL 3.0.21 LTS ZIP x86+x64 works.

[LemonParty]

I built a simple application to test that it is working.
The code:

Code: Pascal  [Select][+][-]

1. program SimpleHTTPServer;
2.  
3. {$mode objfpc}{$H+}
4.  
5. uses
6.   {$IFDEF UNIX}
7.   cthreads,
8.   {$ENDIF}
9.   Classes, fphttpserver, opensslsockets
10.   { you can add units after this };
11.  
12. {$R *.res}
13.  
14. type
15.  
16.   { TTempObj }
17.  
18.   TTempObj = object
19.   public
20.     procedure ProceedRequest(Sender: TObject; var ARequest: TFPHTTPConnectionRequest; var AResponse: TFPHTTPConnectionResponse);
21.   end;
22.  
23. { TTempObj }
24.  
25. procedure TTempObj.ProceedRequest(Sender: TObject;
26.   var ARequest: TFPHTTPConnectionRequest;
27.   var AResponse: TFPHTTPConnectionResponse);
28. begin
29.   WriteLn('1');
30.   AResponse.Content:= ARequest.QueryString + 'Test';
31.   AResponse.Code:= 200;
32. end;
33.  
34. var
35.   TempObj: TTempObj;
36.   Server: TFPHttpServer;
37. begin
38.   Server:= TFPHttpServer.Create(nil);
39.   Server.UseSSL:= True;
40.   Server.Port:= 443;
41.   Server.OnRequest:= @TempObj.ProceedRequest;
42.   Server.ThreadMode:= tmThread;
43.   Server.Active:= True;
44.   Server.Free;
45. end.
46.  

When I run it and trying access http://localhost:443/here I getting ERR_CONNECTION_RESET and nothing input into console. What is wrong?

[LeP]

You must use a certificate for your server to use SSL.

Create one with OpenSSL if you server is  local or with Let's Encrypt is the server is public.

Next time, if you want to download OpenSSL runtime, you can download here (a lot of version availbale for all platforms): https://github.com/TaurusTLS-Developers/OpenSSL-Distribution/releases

[LemonParty]

https://wiki.freepascal.org/fphttpserver This page says

If you do not set the certificate details, the HTTP server component will generate a temporary certificate, which may lead to a warning being displayed in the browser.

[LemonParty]

I figure out. I have to use this url https://localhost/here . Now it works.

[LemonParty]

How can I get route from Request?
I mean for https://localhost/here it should be /here.

[LeP]

I cannot help you more than this 'cause I don't know nothing about FPC web.

Attached: cert files (Crt and Private key) with config and command line instructions to create new one every time you need it.

Bye

[LemonParty]

Thank you, LeP.
I figure out how to get route. It is ARequest.URL property.

[LeP]

Thank you, LeP.
I figure out how to get route. It is ARequest.URL property.

I know, I use Indy and it exposed all things.

This is a sample (there is also FRemoteIP not visible in the screenshot).

URL is a pproperty that contain the full domain name (i.e.: www.google.com').
DOCUMENT is a property the contain the rest of the "line" (i.e.: /Index.html).