man pam_securetty (8): Limit root login to special devices

SYNOPSIS

pam_securetty.so [debug]

DESCRIPTION

pam_securetty is a PAM module that allows root logins only if the user is logging in on a "secure" tty, as defined by the listing in /etc/securetty. pam_securetty also checks to make sure that /etc/securetty is a plain file and not world writable. It will also allow root logins on the tty specified with console= switch on the kernel command line and on ttys from the /sys/class/tty/console/active.

This module has no effect on non-root users and requires that the application fills in the PAM_TTY item correctly.

For canonical usage, should be listed as a required authentication method before any sufficient authentication methods.

OPTIONS

debug

: Print debug information.

noconsole

: Do not automatically allow root logins on the kernel console device, as specified on the kernel command line or by the sys file, if it is not also specified in the /etc/securetty file.

MODULE TYPES PROVIDED

Only the auth module type is provided.

RETURN VALUES

PAM_SUCCESS

: The user is allowed to continue authentication. Either the user is not root, or the root user is trying to log in on an acceptable device.

PAM_AUTH_ERR

: Authentication is rejected. Either root is attempting to log in via an unacceptable device, or the /etc/securetty file is world writable or not a normal file.

PAM_INCOMPLETE

: An application error occurred. pam_securetty was not able to get information it required from the application that called it.

PAM_SERVICE_ERR

: An error occurred while the module was determining the user's name or tty, or the module could not open /etc/securetty.

PAM_USER_UNKNOWN

: The module could not find the user name in the /etc/passwd file to verify whether the user had a UID of 0. Therefore, the results of running this module are ignored.

EXAMPLES

auth  required  pam_securetty.so
auth  required  pam_unix.so

AUTHOR

pam_securetty was written by Elliot Lee <[email protected]>.