Are there other files besides su that need to be installed to gain root access on an Android device? I know that installing a "superuser" app isn't strictly necessary but merely important from a security perspective.
What I want to know is whether simply transferring a working su binary to a device is enough to "root" an Android device. By "working" su binary, I mean having su installed at the proper location and blessed with the proper permissions.
Note: I'm not asking about the means (e.g. some esoteric security hole, adb, a bogus *ab backup file, or a recovery zip) but the goal, the absolute minimum number of file(s) that need to be transferred to root an Android device.