dm/dm.8

   1 .\"     $NetBSD: dm.8,v 1.6 1998/06/08 12:41:41 lukem 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
  67 be run.
  68 .Pp
  69 The file
  70 .Pa /etc/nogames
  71 may be used to
  72 .Dq turn off
  73 game playing.
  74 If the file exists, no game playing is allowed; the contents of the file
  75 will be displayed to any user requesting a game.
  76 .Sh FILES
  77 .Bl -tag -width /var/log/games.log -compact
  78 .It Pa /etc/dm.conf
  79 configuration file
  80 .It Pa /etc/nogames
  81 turns off game playing
  82 .It Pa /usr/games/hide
  83 directory of ``real'' binaries
  84 .It Pa /var/log/games.log
  85 game logging file
  86 .El
  87 .Sh SEE ALSO
  88 .Xr dm.conf 5
  89 .Sh HISTORY
  90 The
  91 .Nm
  92 command appeared in
  93 .Bx 4.3 tahoe .
  94 .Sh SECURITY CONSIDERATIONS
  95 Two issues result from
  96 .Nm
  97 running the games setgid
  98 .Dq games .
  99 First, all games that allow users to run
 100 .Ux
 101 commands should carefully
 102 set both the real and effective group id's immediately before executing
 103 those commands.
 104 Probably more important is that
 105 .Nm
 106 never be setgid anything but
 107 .Dq games
 108 so that compromising a game will result only in
 109 the user's ability to play games at will.
 110 Secondly, games which previously had no reason to run setgid and which
 111 accessed user files may have to be modified.