nest-systemd-user

Runs systemd --user within systemd --user

On systemd-based systems, there is an implicit assumption that the user will only have one graphical session active at any one time. This is because the systemd --user environment is shared between all user sessions, and there is only room for one DISPLAY variable.

This has been of some inconvenience for the xrdp project. A commonly requested feature is for users to be able to log in to the machine console and xrdp at the same time. This is particularly true for lesser-experienced users, maybe using a smaller machine such as a Raspberry PI.

@akarl10 has discovered that is possible to run one systemd --user instance within another. This allows for the possibility of one or more xrdp sessions to use private systemd --user instances. This was announced in xrdp issue #2491.

This repository contains a tool which can be retro-fitted to xrdp v0.9.x installations.

At the moment this is an alpha-quality tool. Feedback and issuea are welcome.

how to use this tool in conjunction with xrdp

To use this tool with xrdp the script startwm.sh should be adapted

First you should place systemd_user_context.sh in the same directory as startwm.sh:-

• On Fedora or EPEL-based systems, startwm.sh is in /usr/libexec/xrdp/
• On all other systems startwm.sh is (probably) in /etc/xrdp.

The next step is putting this somewhere near the top of startwm.sh. It can be anywhere in the script as long as it is before the Xsession call

# On systemd system?
#
# If so, start a private "systemd --user" instance
if [ -x /usr/bin/systemctl -a "$XDG_RUNTIME_DIR" = "/run/user/"`id -u` ]
then
    eval "`${0%/*}/systemd_user_context.sh init -p $$`"

    # may be used by reconnect.sh to find the matching logind session
    if [ -n "$XDG_SESSION_ID" ]; then
        echo $XDG_SESSION_ID > $XDG_RUNTIME_DIR/login-session-id
    fi
fi

If you also want to unlock your xrdp screen when you reconnect to your session preventing to type you password twice you might put something like this in reconnectwh.sh

# xrdp-sesman knows nothing about the nested session, so try to guess
# XDG_RUNTIME_DIR
[ -z "$XDG_RUNTIME_DIR" -a -e /run/user/$(id -u) ] && XDG_RUNTIME_DIR=/run/user/$(id -u)

eval "`${0%/*}/systemd_user_context.sh get`"

test -e $XDG_RUNTIME_DIR/login-session-id && \
        loginctl unlock-session $(cat $XDG_RUNTIME_DIR/login-session-id)