OIDC/OAuth support

[luochen1990]

Is your feature request related to a problem? Please describe.

I'm always frustrated when I want to share a big file with my friends, since allowing unauthorised user to upload big file might cause the disk space abused.

Describe the solution you'd like

Allowing user login via OIDC, and add limitation options for login user and unauthorised user seperatelly.

ALLOW_UPLOAD = "none" / "login" / "all"
ALLOW_UPLOAD_FILE =  "none" / "login" / "all"

[tecosaur]

Hello! I've wanted to do something similar myself, and in case you find it helpful I'll share how Caddy + Authelia can be used to make uploading require login:

pastes.example.com {
    route /raw/* {
        reverse_proxy :4144 {
            header_down Content-Type "text/plain; charset=UTF-8"
        }
    }
    @public path /static/* /upload/* /file/* /p/* /raw/* /u/* /qr/* /auth/* /auth_file/*
    route @public {
        reverse_proxy :4144
    }
    route * {
        import auth
        reverse_proxy :4144
    }
}

[tecosaur]

The one thing that I'd actually consider helpful is allowing removal of password auth for the admin page, since I'm now handling access/auth myself.