Custom domain for self-signed apps

[Severin Friede]

I need your help for my next issue. When browsing through the
"external/sepolicy" folder I found out that SEAndroid is able to recognize
apps by the signed key and assign them in the appropriate domain. Is it
possible to extend  this behavior with my own signing key? I want to assign
my own apps (signed with my key) to a custom domain and provide different
permissions for them.