group.conf - configuration file for the pam_group module


   The pam_group PAM module does not authenticate the user, but instead it
   grants group memberships (in the credential setting phase of the
   authentication module) to the user. Such memberships are based on the
   service they are applying for.

   For this module to function correctly there must be a correctly
   formatted /etc/security/group.conf file present. White spaces are
   ignored and lines maybe extended with '\' (escaped newlines). Text
   following a '#' is ignored to the end of the line.

   The syntax of the lines is as follows:


   The first field, the services field, is a logic list of PAM service
   names that the rule applies to.

   The second field, the tty field, is a logic list of terminal names that
   this rule applies to.

   The third field, the users field, is a logic list of users, or a UNIX
   group, or a netgroup of users to whom this rule applies. Group names
   are preceded by a '%' symbol, while netgroup names are preceded by a
   '@' symbol.

   For these items the simple wildcard '*' may be used only once. With
   UNIX groups or netgroups no wildcards or logic operators are allowed.

   The times field is used to indicate "when" these groups are to be given
   to the user. The format here is a logic list of day/time-range entries.
   The days are specified by a sequence of two character entries, MoTuSa
   for example is Monday Tuesday and Saturday. Note that repeated days are
   unset MoMo = no day, and MoWk = all weekdays bar Monday. The two
   character combinations accepted are Mo Tu We Th Fr Sa Su Wk Wd Al, the
   last two being week-end days and all 7 days of the week respectively.
   As a final example, AlFr means all days except Friday.

   Each day/time-range can be prefixed with a '!' to indicate "anything
   but". The time-range part is two 24-hour times HHMM, separated by a
   hyphen, indicating the start and finish time (if the finish time is
   smaller than the start time it is deemed to apply on the following

   The groups field is a comma or space separated list of groups that the
   user inherits membership of. These groups are added if the previous
   fields are satisfied by the user's request.

   For a rule to be active, ALL of service+ttys+users must be satisfied by
   the applying process.


   These are some example lines which might be specified in

   Running 'xsh' on tty* (any ttyXXX device), the user 'us' is given
   access to the floppy (through membership of the floppy group)


   Running 'xsh' on tty* (any ttyXXX device), the user 'sword' is given
   access to games (through membership of the floppy group) after work

       xsh; tty* ;sword;!Wk0900-1800;games, sound
       xsh; tty* ;*;Al0900-1800;floppy

   Any member of the group 'admin' running 'xsh' on tty*, is granted
   access (at any time) to the group 'plugdev'

       xsh; tty* ;%admin;Al0000-2400;plugdev


   pam_group(8), pam.d(5), pam(7)


   pam_group was written by Andrew G. Morgan <>.


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