I've found a flutter plugin on pub.dev that is licensed under MIT, but in its build.gradle for Android building it references another library that seems to be a fork of a GPLv2 library. In turn, I would have thought the plugin would also have to be GPL meaning they incorrectly licensed it.
However, I then noticed the build.gradle uses jitpack in order to download compiled artifacts of the GPL library. In the past I have heard that a program under another license can legally interface with a compiled GPL binary as long as the program itself isn't linked with it (eg: using std pipes) as long as a copy of the GPL license is included and where to find the binary's source.
Is this likely what is happening in this case, or should the plugin be licensed under GPLv2? I've seen a few plugins that seem to do this same thing, are these all violating the GPL or have I got that wrong?
EDIT: Okay so I've been asked to add some more specifics of the actual plugin in question. The plugin I am talking about is flutter_openvpn. It is MIT licensed, but on its Android side uses a fork of ics-openvpn, which is a GPLv2 library for Android. This is the fork I am talking about, and as you can see it too is correctly released under GPLv2.
In the build process, the build.gradle uses jitpack so that the GPL library is compiled into an aar before being used by the plugin:
rootProject.allprojects {
repositories {
google()
jcenter()
maven { url 'https://jitpack.io' }
}
}
...
dependencies {
implementation 'com.github.Topfreelancerdeveloperr:flutter_openvpn_library_updated:3361996fa1'
}
However, the plugin then creates an instance of the VPN object in this library from its own code and passes some parameters to it. Since its instantiating an object of the library this should come under GPL right? Or does this specific use case allow for the MIT license in the plugin?
As for the iOS side I'm ignoring that for the sake of this question, I'm just interested in whether the Android build process abides by GPL rules or not.
Update: After some thinking I had a theory. Is the MIT license legitimate since the online source code only contains a reference to the repository of the GPL library, but upon use of the plugin when this GPL dependency is downloaded does the whole application become GPL? It seems like that could be what's going on, but if so that can be very misleading for people using plugins like this...