PAM_SECURETTY(8)          (06/08/2020)           PAM_SECURETTY(8)

     NAME
          pam_securetty - 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 the securetty file. pam_securetty checks at
          first, if /etc/securetty exists. If not and it was built
          with vendordir support, it will use <vendordir>/securetty.
          pam_securetty also checks that the securetty files are plain
          files 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
              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 securetty file
              is world writable or not a normal file.

          PAM_BUF_ERR

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     PAM_SECURETTY(8)          (06/08/2020)           PAM_SECURETTY(8)

              Memory buffer error.

          PAM_CONV_ERR
              The conversation method supplied by the application
              failed to obtain the username.

          PAM_INCOMPLETE
              The conversation method supplied by the application
              returned PAM_CONV_AGAIN.

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

          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

     SEE ALSO
          securetty(5), pam.conf(5), pam.d(5), pam(7)

     AUTHOR
          pam_securetty was written by Elliot Lee <sopwith@cuc.edu>.

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