How do I install a backdoor to logon to Ubuntu?

Question

Please tell me, how can I install a backdoor so that I can reset the password from recovery mode, as well as from terminal. I would prefer that this be something that can only be done while installing and that it would notify you for a few days after installing that there is a backdoor so that you can't install Ubuntu on someone's computer with a backdoor to hack/crack there information.

Answer 1

You likely don't need a "backdoor".

You can reset the password for any user by booting to recovery mode or using a Live CD. Both these methods give you root on a system by virtue of having physical access. The only way to deny this sort of thing is using full disk encryption with a strong password you enter on boot... But yeah, that will deny any sort of recovery if you forget it.

If you need to handle this remotely, you could set a root password (sudo passwd) and enable root login in /etc/ssh/sshd_config but you should consider that a security risk. root login is disabled for a reason and I honestly don't think it's worth it...