dm/dm.8

   1 .\"     $NetBSD: dm.8,v 1.7 2002/09/26 18:32:00 wiz Exp $
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  34 .\"     @(#)dm.8        8.1 (Berkeley) 5/31/93
  35 .\"
  36 .Dd May 31, 1993
  37 .Dt DM 8
  38 .Os
  39 .Sh NAME
  40 .Nm dm
  41 .Nd dungeon master
  42 .Sh SYNOPSIS
  43 .Nm ln
  44 .Fl s Cm dm Ar game
  45 .Sh DESCRIPTION
  46 .Nm
  47 is a program used to regulate game playing.
  48 .Nm
  49 expects to be invoked with the name of a game that a user wishes to play.
  50 This is done by creating symbolic links to
  51 .Nm "" ,
  52 in the directory
  53 .Pa /usr/games
  54 for all of the regulated games.
  55 The actual binaries for these games should be placed in a
  56 .Dq hidden
  57 directory,
  58 .Pa /usr/games/hide ,
  59 that may only be accessed by the
  60 .Nm
  61 program.
  62 .Nm
  63 determines if the requested game is available and, if so, runs it.
  64 The file
  65 .Pa /etc/dm.conf
  66 controls the conditions under which games may be run.
  67 .Pp
  68 The file
  69 .Pa /etc/nogames
  70 may be used to
  71 .Dq turn off
  72 game playing.
  73 If the file exists, no game playing is allowed; the contents of the file
  74 will be displayed to any user requesting a game.
  75 .Sh FILES
  76 .Bl -tag -width /var/log/games.log -compact
  77 .It Pa /etc/dm.conf
  78 configuration file
  79 .It Pa /etc/nogames
  80 turns off game playing
  81 .It Pa /usr/games/hide
  82 directory of ``real'' binaries
  83 .It Pa /var/log/games.log
  84 game logging file
  85 .El
  86 .Sh SEE ALSO
  87 .Xr dm.conf 5
  88 .Sh HISTORY
  89 The
  90 .Nm
  91 command appeared in
  92 .Bx 4.3 tahoe .
  93 .Sh SECURITY CONSIDERATIONS
  94 Two issues result from
  95 .Nm
  96 running the games setgid
  97 .Dq games .
  98 First, all games that allow users to run
  99 .Ux
 100 commands should carefully
 101 set both the real and effective group ids immediately before executing
 102 those commands.
 103 Probably more important is that
 104 .Nm
 105 never be setgid anything but
 106 .Dq games
 107 so that compromising a game will result only in
 108 the user's ability to play games at will.
 109 Secondly, games which previously had no reason to run setgid and which
 110 accessed user files may have to be modified.