pam_rootok

Allow root without password

$ auth sufficient pam_rootok.so

pam_rootok.so

pam_rootok succeeds if user is root. Allows password-less root operations.
The module checks UID equals zero. Used for su and similar.

No parameters. Checks for UID 0.

Only for root user. Use with sufficient. Security implications.

pam_rootok allows root user bypass for commands like su.

pam(8), su(1), pam_wheel(8)