dm(8)

NAME

dm - dungeon master

SYNOPSIS

ln -s dm game

DESCRIPTION

dm is a program used to regulate game playing. dm expects

to be invoked
with the name of a game that a user wishes to play. This is

done by cre
ating symbolic links to , in the directory /usr/games for

all of the reg
ulated games. The actual binaries for these games should be

placed in a
``hidden'' directory, /usr/lib/games/dm, that may only be

accessed by the
dm program. dm determines if the requested game is avail

able and, if so,
runs it. The file /etc/dm.conf controls the conditions un

der which games
may be run.

The file /etc/nogames may be used to ``turn off'' game play

ing. If the
file exists, no game playing is allowed; the contents of the

file will be
displayed to any user requesting a game.

FILES

/etc/dm.conf configuration file
/etc/nogames turns off game playing
/usr/lib/games/dm directory of ``real'' binaries
/var/games/games.log game logging file

SEE ALSO

dm.conf(5)

HISTORY

The dm command appeared in 4.3BSD-Tahoe.

SECURITY CONSIDERATIONS

Two issues result from dm running the games setgid

``games''. First, all
games that allow users to run UNIX commands should carefully

set both the
real and effective group id's immediately before executing

those com
mands. Probably more important is that dm never be setgid

anything but
``games'' so that compromising a game will result only in

the user's
ability to play games at will. Secondly, games which previ

ously had no
reason to run setgid and which accessed user files may have

to be modi
fied.

BSD May 31, 1993

BSD