Inquiry Regarding Specific Open Source License: GPL-2.0-only or GPL-2.0-or-later for Arch Packaging Repository Update

[xingwozhonghua126]

Dear [Maintainer/6tunnel]

I am writing to request clarification on the specific open source license under which the 6tunnel is distributed. My aim is to update the Arch Linux packaging repository, and an accurate understanding of the licensing terms is essential for compliance.

Currently, there seems to be ambiguity whether the project is licensed under the “GPL-2.0-only” or the “GPL-2.0-or-later” version of the GNU General Public License. The distinction is important because the “GPL-2.0-only” license restricts the project’s code to only version 2 of the GPL, while the “GPL-2.0-or-later” allows users to choose any later version of the GPL, as published by the Free Software Foundation.

In order to proceed with the correct packaging and distribution protocol within the Arch User Repository (AUR) and to ensure adherence to the project’s intended licensing terms, I kindly request confirmation on the following:

Is 6tunnel licensed under “GPL-2.0-only” or “GPL-2.0-or-later”?
If available, could you point me to where the licensing information is explicitly stated within the source code or documentation for future reference?
Should I attribute the license information in a specific way when updating the PKGBUILD file for the Arch User Repository?
Your prompt response would be greatly appreciated, as it will assist in maintaining the integrity of the Arch User Repository and ensure that all open source licensing requirements are properly met.

Thank you for your attention to this matter and for your contributions to the open source community.

Best regards,
shijie.chen
xingwozhonghua@126.com

https://gitlab.archlinux.org/archlinux/packaging/packages/6tunnel/-/merge_requests/1/diffs

https://spdx.org/licenses/

[wojtekka]

It doesn't say "or any later" anywhere, so it's GPL v2.0 only.