Aports contributions - license & copyright?

The question was brought up with this PR - https://github.com/alpinelinux/aports/pull/4490/files and has also previously been touched in https://bugs.alpinelinux.org/issues/7423

The https://git.alpinelinux.org/cgit/aports/tree/README.md file nor is there another file mentioning it in the git repo.
and I have searched the sites and wiki and can not find the answer.

So I have the following questions:

• Which license are the aports themselves (APKBUILD, pre, post…) under?
• Who are the copyright holders (the contributor or given to the project)?
• Should AL have a CLA (https://en.wikipedia.org/wiki/Contributor\_License\_Agreement)?

(from redmine: issue id 9074, created on 2018-07-11)