Filter file types on push

I’m using Gitlab CE with nginx and pg. I need to filter types of files being pushed (by http/s) to the repository.

I want to be able to limit the type of files that actually crossover to the repository.

i.e. someone wants to push their work to the remote repository (git push). Their files include an exe file. I want every file except the exe file to be saved in the repo.

I would love to accomplish this through configuration if possible. Else, i don’t mind touching code (i would appreciate a pointer to where, though).