Accurately, I have to declare that the private key of RSA using in my IntelliJ IDEA License Server were extracted from lanyus's IntelliJIDEALicenseServer nearly three years ago. What I did is just to come out with the source code of IntelliJ IDEA License Server written in java.
Importantly, if you think the source code is interesting, please star my repo. Thanks.
###How to run
java -jar "./IntelliJ IDEA License Server.jar" [-ip] [-port]
ps: If you wanna passby the lastest validation, such as Webstorm 2018.1, you should disconnect the internet while launching the jetbrain IDE, since the fake server does register itself.