How to implement a USB dongle protection for software?

Question

USB

Hello.
Tell or give a tip that you can read about the USB protection of the application. For example: software (for example, written in WinForms) works only through an inserted USB flash drive, on which the key is located. No flash drive - the software does not work.
UPD:
Comrades, thanks for helping to understand the subject area. Now the question is different: how to implement hardware protection without using the finished products listed below? At least the simple one. What and where to google?

Answer 1

You need a Sentinel security key (this is the current generation of HASP keys).
Here you can download and test the SDK and watch video tutorials on how it all works: safenet-sentinel.ru/sdk

Answer 2

Quite a perverted option, to transfer some of the software functions to the microcontroller attached via USB. the cost of hacking is estimated at $ 2,000. the most chic if for each client there will be its own "flash drive" with its own set of functions sewn into it.

Answer 3

Well, the simplest thing is to check for the presence of a piece of iron with a certain VID and PID, as well as any of its properties, and for this method there is no need even to collective farm the device, because there are tons of interface cords, flash drives, etc. which can be abused ;-) by turning them into unique identifiers...
Further, you can stir up any interaction directly with the device, starting with a password-revocation and floating codes and ending, as noted above, with the functional use of the device, which, by the way, is not so and perversion...
IMHO you always need to start with building threat models, from what exactly and what exactly do you want to protect?
And from this it’s already dancing, because your executable code can be unpacked, patched from greed and cynically packed back :-) Or a key device can be simulated in software, or even recreated in hardware ... And there are situations when you need to protect the working algorithm itself from reverse engineering and / or unauthorized exploitation, and when its value is measured in hundreds of kilodollars, high art already begins here.
In most everyday tasks, it is enough to make the process of learning and hacking laborious enough that it would not be common to do it for fun, and no one will do it :-)