PAM_SYSTEMD(8)                             pam_systemd                             PAM_SYSTEMD(8)



NAME
       pam_systemd - Register user sessions in the systemd login manager

SYNOPSIS
       pam_systemd.so

DESCRIPTION
       pam_systemd registers user sessions with the systemd login manager systemd-
       logind.service(8), and hence the systemd control group hierarchy.

       On login, this module ensures the following:

        1. If it does not exist yet, the user runtime directory /run/user/$USER is created and
           its ownership changed to the user that is logging in.

        2. The $XDG_SESSION_ID environment variable is initialized. If auditing is available and
           pam_loginuid.so run before this module (which is highly recommended), the variable is
           initialized from the auditing session id (/proc/self/sessionid). Otherwise an
           independent session counter is used.

        3. A new systemd scope unit is created for the session. If this is the first concurrent
           session of the user, an implicit slice below user.slice is automatically created and
           the scope placed in it. In instance of the system service user@.service which runs the
           systemd user manager instance.

       On logout, this module ensures the following:

        1. If this is enabled, all processes of the session are terminated. If the last
           concurrent session of a user ends, his user systemd instance will be terminated too,
           and so will the user's slice unit.

        2. If the last concurrent session of a user ends, the $XDG_RUNTIME_DIR directory and all
           its contents are removed, too.

       If the system was not booted up with systemd as init system, this module does nothing and
       immediately returns PAM_SUCCESS.

OPTIONS
       The following options are understood:

       class=
           Takes a string argument which sets the session class. The XDG_SESSION_CLASS
           environmental variable takes precedence. One of "user", "greeter", "lock-screen" or
           "background". See sd_session_get_class(3) for details about the session class.

       type=
           Takes a string argument which sets the session type. The XDG_SESSION_TYPE
           environmental variable takes precedence. One of "unspecified", "tty", "x11", "wayland"
           or "mir". See sd_session_get_type(3) for details about the session type.

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

MODULE TYPES PROVIDED
       Only session is provided.

ENVIRONMENT
       The following environment variables are set for the processes of the user's session:

       $XDG_SESSION_ID
           A session identifier, suitable to be used in filenames. The string itself should be
           considered opaque, although often it is just the audit session ID as reported by
           /proc/self/sessionid. Each ID will be assigned only once during machine uptime. It may
           hence be used to uniquely label files or other resources of this session.

       $XDG_RUNTIME_DIR
           Path to a user-private user-writable directory that is bound to the user login time on
           the machine. It is automatically created the first time a user logs in and removed on
           his final logout. If a user logs in twice at the same time, both sessions will see the
           same $XDG_RUNTIME_DIR and the same contents. If a user logs in once, then logs out
           again, and logs in again, the directory contents will have been lost in between, but
           applications should not rely on this behavior and must be able to deal with stale
           files. To store session-private data in this directory, the user should include the
           value of $XDG_SESSION_ID in the filename. This directory shall be used for runtime
           file system objects such as AF_UNIX sockets, FIFOs, PID files and similar. It is
           guaranteed that this directory is local and offers the greatest possible file system
           feature set the operating system provides.

       The following environment variables are read by the module and may be used by the PAM
       service to pass metadata to the module:

       $XDG_SESSION_TYPE
           The session type. This may be used instead of session= on the module parameter line,
           and is usually preferred.

       $XDG_SESSION_CLASS
           The session class. This may be used instead of class= on the module parameter line,
           and is usually preferred.

       $XDG_SESSION_DESKTOP
           A single, short identifier string for the desktop environment. This may be used to
           indicate the session desktop used, where this applies and if this information is
           available. For example: "GNOME", or "KDE". It is recommended to use the same
           identifiers and capitalization as for $XDG_CURRENT_DESKTOP, as defined by the Desktop
           Entry Specification[1].

       $XDG_SEAT
           The seat name the session shall be registered for, if any.

       $XDG_VTNR
           The VT number the session shall be registered for, if any. (Only applies to seats with
           a VT available, such as "seat0")

EXAMPLE
           #%PAM-1.0
           auth       required     pam_unix.so
           auth       required     pam_nologin.so
           account    required     pam_unix.so
           password   required     pam_unix.so
           session    required     pam_unix.so
           session    required     pam_loginuid.so
           session    required     pam_systemd.so

SEE ALSO
       systemd(1), systemd-logind.service(8), logind.conf(5), loginctl(1), pam.conf(5), pam.d(5),
       pam(8), pam_loginuid(8), systemd.scope(5), systemd.slice(5), systemd.service(5)

NOTES
        1. Desktop Entry Specification
           http://standards.freedesktop.org/desktop-entry-spec/latest/



systemd 215                                                                        PAM_SYSTEMD(8)