pam_systemd_home(8) — Linux manual page

NAME | SYNOPSIS | DESCRIPTION | OPTIONS | MODULE TYPES PROVIDED | ENVIRONMENT | EXAMPLE | SEE ALSO | COLOPHON

PAM_SYSTEMD_HOME(8)         pam_systemd_home         PAM_SYSTEMD_HOME(8)

NAME         top

       pam_systemd_home - Automatically mount home directories managed
       by systemd-homed.service on login, and unmount them on logout

SYNOPSIS         top

       pam_systemd_home.so

DESCRIPTION         top

       pam_systemd_home ensures that home directories managed by
       systemd-homed.service(8) are automatically activated (mounted) on
       user login, and are deactivated (unmounted) when the last session
       of the user ends.

OPTIONS         top

       The following options are understood:

       suspend=
           Takes a boolean argument. If true, the home directory of the
           user will be suspended automatically during system suspend;
           if false it will remain active. Automatic suspending of the
           home directory improves security substantially as secret key
           material is automatically removed from memory before the
           system is put to sleep and must be re-acquired (through user
           re-authentication) when coming back from suspend. It is
           recommended to set this parameter for all PAM applications
           that have support for automatically re-authenticating via PAM
           on system resume. If multiple sessions of the same user are
           open in parallel the user's home directory will be left
           unsuspended on system suspend as long as at least one of the
           sessions does not set this parameter to on. Defaults to off.

           Note that TTY logins generally do not support
           re-authentication on system resume. Re-authentication on
           system resume is primarily a concept implementable in
           graphical environments, in the form of lock screens brought
           up automatically when the system goes to sleep. This means
           that if a user concurrently uses graphical login sessions
           that implement the required re-authentication mechanism and
           console logins that do not, the home directory is not locked
           during suspend, due to the logic explained above. That said,
           it is possible to set this field for TTY logins too, ignoring
           the fact that TTY logins actually don't support the
           re-authentication mechanism. In that case the TTY sessions
           will appear hung until the user logs in on another virtual
           terminal (regardless if via another TTY session or
           graphically) which will resume the home directory and unblock
           the original TTY session. (Do note that lack of screen
           locking on TTY sessions means even though the TTY session
           appears hung, keypresses can still be queued into it, and the
           existing screen contents be read without re-authentication;
           this limitation is unrelated to the home directory management
           pam_systemd_home and systemd-homed.service implement.)

           Turning this option on by default is highly recommended for
           all sessions, but only if the service managing these sessions
           correctly implements the aforementioned re-authentication.
           Note that the re-authentication must take place from a
           component running outside of the user's context, so that it
           does not require access to the user's home directory for
           operation. Traditionally, most desktop environments do not
           implement screen locking this way, and need to be updated
           accordingly.

           This setting may also be controlled via the
           $SYSTEMD_HOME_SUSPEND environment variable (see below), which
           pam_systemd_home reads during initialization and sets for
           sessions. If both the environment variable is set and the
           module parameter specified the latter takes precedence.

       debug[=]
           Takes an optional boolean argument. If yes or without the
           argument, the module will log debugging information as it
           operates.

MODULE TYPES PROVIDED         top

       The module provides all four management operations: auth,
       account, session, password.

ENVIRONMENT         top

       The following environment variables are initialized by the module
       and available to the processes of the user's session:

       $SYSTEMD_HOME=1
           Indicates that the user's home directory is managed by
           systemd-homed.service.

       $SYSTEMD_HOME_SUSPEND=
           Indicates whether the session has been registered with the
           suspend mechanism enabled or disabled (see above). The
           variable's value is either "0" or "1". Note that the module
           both reads the variable when initializing, and sets it for
           sessions.

EXAMPLE         top

       Here's an example PAM configuration fragment that permits users
       managed by systemd-homed.service to log in:

           #%PAM-1.0
           auth      sufficient pam_unix.so
           -auth     sufficient pam_systemd_home.so
           auth      required   pam_deny.so

           account   required   pam_nologin.so
           -account  sufficient pam_systemd_home.so
           account   sufficient pam_unix.so
           account   required   pam_permit.so

           -password sufficient pam_systemd_home.so
           password  sufficient pam_unix.so sha512 shadow try_first_pass try_authtok
           password  required   pam_deny.so

           -session  optional   pam_keyinit.so revoke
           -session  optional   pam_loginuid.so
           -session  optional   pam_systemd_home.so
           -session  optional   pam_systemd.so
           session   required   pam_unix.so

SEE ALSO         top

       systemd(1), systemd-homed.service(8), homed.conf(5), homectl(1),
       pam_systemd(8), pam.conf(5), pam.d(5), pam(8)

COLOPHON         top

       This page is part of the systemd (systemd system and service
       manager) project.  Information about the project can be found at
       ⟨http://www.freedesktop.org/wiki/Software/systemd⟩.  If you have
       a bug report for this manual page, see
       ⟨http://www.freedesktop.org/wiki/Software/systemd/#bugreports⟩.
       This page was obtained from the project's upstream Git repository
       ⟨https://github.com/systemd/systemd.git⟩ on 2020-12-18.  (At that
       time, the date of the most recent commit that was found in the
       repository was 2020-12-18.)  If you discover any rendering
       problems in this HTML version of the page, or you believe there
       is a better or more up-to-date source for the page, or you have
       corrections or improvements to the information in this COLOPHON
       (which is not part of the original manual page), send a mail to
       man-pages@man7.org

systemd 247                                          PAM_SYSTEMD_HOME(8)

Pages that refer to this page: systemd.directives(7)systemd.index(7)pam_systemd(8)systemd-homed.service(8)