Read card UID using Java applet or JavaScript or...?

Question

JavaScript

As the search showed, this topic is quite new for Habr.
The problem with the subject arose when it became clear that not all devices (readers) have an interface implemented through PKCS (Cryptoki).
Basically, everything works through a virtual COM port.
Perhaps you, colleagues, have at least some experience in this matter in order to suggest
how best to implement reading, having only a reader working through a COM port.
I understand the task as follows: write a windows application that will be an interface to the reader for ... java? javascript? socket?
What is easier/can be attached to so that the website can interact with the program?
Thank you in advance.

Answer 1

Similar to how it is done with the EDS. There is a plugin for the browser, you can access the plugin from the JS code that is downloaded from your site. The browser plug-in accordingly goes already where it is necessary by the local machine. Here CRYPTO-PRO does this to obtain an EDS certificate.

Answer 2

JS will certainly not be able to interact with the com port.
Either a Java applet, or a separate desktop program that will interact with the port and also listen to a thread on the port on localhost to interact with the site.

Answer 3

By analogy with webmoney keeper.
2 requests are made on the site:
1) To the site with the signal “we are waiting for a key, from user X”, for example ajax
2) To the program with the signal “give the key”, for example post to an invisible iframe (it can be cross-domain ajax, but it can get out there a lot of problems with Cross-site scripting and Same origin policy).
Further, the program, having received the request “issue the key”, sends the key directly to the server with the message “user X key, such and such”
The server checks the key, if it is valid, in response to “we are waiting for the key, from user X”, it gives an authorization cookie.