this is a Secure Display Manager.
essentially, sdm runs Xdialog on the X-terminal, and connects
to a server via ssh. it can also do automatic passwordless
logins with ssh keys.
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License, version 2 or any later version. email@example.com
a basic overview:
sdm has two main packages (and the doc package).
the first package, sdm, is installed on a server. it contains
the sdm-session script, which is called remotely by the
it's essential to have /etc/ssh/sshd_config configured with:
the second package, sdm-terminal, is installed on the
"terminal" or in the chrooted directory of the terminal(if
terminals are "diskless" terminals). it contains
/usr/sbin/sdm, which should be run from the terminal's
/etc/inittab, like so:
this would cause sdm to run (and respawn when it dies) when
entering runlevel 5.
sdm calls another script, /usr/sbin/sdm-login. this script
gathers information about the user login, password or key,
server to login to, etc. some of this information may come
from /etc/sdm/sdm.config or /etc/sdm/sdm.config.$hostname, or
the getLoginInfo script, which usually uses Xdialog.
sdm-login the attempts to ssh to the server with X11Forwarding
enabled, running the sdm-session program, which will source
also note that on the terminal, there must be a valid key in
/root/.ssh/known_hosts for any servers you wish to log into,
otherwise sdm will hang asking if you want to connect.
sdm-ssh-askpass is a re-write of ssh-askpass using
Xdialog. if the SSH_ASKPASS variable is set, ssh tries to get
any passwords using this program (unless run from a
terminal...) having sdm-ssh-askpass means we don't need to
depend on any of the other ssh-askpass programs, and is
graphically consistant with the login screen. it's also
possible to have a totally graphical login using SSH_ASKPASS.