Switch to SpeakEasy.net DSL

The Modular Manual Browser

Home Page
Manual: (Debian-5.0)
Apropos / Subsearch:
optional field

ACCESS.CONF(5)                 Linux-PAM Manual                 ACCESS.CONF(5)

       access.conf - the login access control table file

       The /etc/security/access.conf file specifies (user/group, host),
       (user/group, network/netmask) or (user/group, tty) combinations for
       which a login will be either accepted or refused.

       When someone logs in, the file access.conf is scanned for the first
       entry that matches the (user/group, host) or (user/group,
       network/netmask) combination, or, in case of non-networked logins, the
       first entry that matches the (user/group, tty) combination. The
       permissions field of that table entry determines whether the login will
       be accepted or refused.

       Each line of the login access control table has three fields separated
       by a ":" character (colon):


       The first field, the permission field, can be either a "+" character
       (plus) for access granted or a "-" character (minus) for access denied.

       The second field, the users/group field, should be a list of one or
       more login names, group names, or ALL (which always matches). To
       differentiate user entries from group entries, group entries should be
       written with brackets, e.g.  (group).

       The third field, the origins field, should be a list of one or more tty
       names (for non-networked logins), host names, domain names (begin with
       "."), host addresses, internet network numbers (end with "."), internet
       network addresses with network mask (where network mask can be a
       decimal number or an internet address also), ALL (which always matches)
       or LOCAL (which matches any string that does not contain a "."
       character). If supported by the system you can use @netgroupname in
       host or user patterns.

       The EXCEPT operator makes it possible to write very compact rules.

       If the nodefgroup is not set, the group file is searched when a name
       does not match that of the logged-in user. Only groups are matched in
       which users are explicitly listed. However the PAM module does not look
       at the primary group id of a user.

       The "#" character at start of line (no space at front) can be used to
       mark this line as a comment line.

       These are some example lines which might be specified in

       User root should be allowed to get access via cron, X11 terminal :0,
       tty1, ..., tty5, tty6.

       + : root : crond :0 tty1 tty2 tty3 tty4 tty5 tty6

       User root should be allowed to get access from hosts which own the IPv4
       addresses. This does not mean that the connection have to be a IPv4
       one, a IPv6 connection from a host with one of this IPv4 addresses does
       work, too.

       + : root :

       + : root :

       User root should get access from network 192.168.201.  where the term
       will be evaluated by string matching. But it might be better to use
       network/netmask instead. The same meaning of 192.168.201.  is or

       + : root : 192.168.201.

       User root should be able to have access from hosts foo1.bar.org and
       foo2.bar.org (uses string matching also).

       + : root : foo1.bar.org foo2.bar.org

       User root should be able to have access from domain foo.bar.org (uses
       string matching also).

       + : root : .foo.bar.org

       User root should be denied to get access from all other sources.

       - : root : ALL

       User foo and members of netgroup admins should be allowed to get access
       from all sources. This will only work if netgroup service is available.

       + : @admins foo : ALL

       User john and foo should get access from IPv6 host address.

       + : john foo : 2001:4ca0:0:101::1

       User john should get access from IPv6 net/mask.

       + : john : 2001:4ca0:0:101::/64

       Disallow console logins to all but the shutdown, sync and all other
       accounts, which are a member of the wheel group.

       -:ALL EXCEPT (wheel) shutdown sync:LOCAL

       All other users should be denied to get access from all sources.

       - : ALL : ALL

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

       Original login.access(5) manual was provided by Guido van Rooij which
       was renamed to access.conf(5) to reflect relation to default config

       Network address / netmask description and example text was introduced
       by Mike Becher <mike.becherATlrz-muenchen.de>.

Linux-PAM Manual                  07/27/2008                    ACCESS.CONF(5)