Add support for 'debug' argument in 2FA integration PAM module

Release notes

Problem to solve

As a DevOps engineer trying to debug the 2FA integration, I need the ability to quickly understand what's going on inside the PAM module without looking at the source code.

Intended users

• Devon (DevOps Engineer)
• Sidney (Systems Administrator)

User experience goal

The user should be able to add debug to the PAM config (e.g. /etc/pam.d/sshd for ubuntu) to enable debugging. For example:

auth required gitlab-shell-two-factor-pam.so debug

The debug output is then included in a system log file. For instance /var/log/auth.log on ubuntu.

Proposal

Further details

Permissions and Security

Documentation

Availability & Testing

What does success look like, and how can we measure that?

What is the type of buyer?

Is this a cross-stage feature?

Links / references