The device_maps File

You can examine the /etc/security/device_maps file to determine the device names, device types, and device-special files that are associated with each allocatable device. See the device_maps(4) man page. Device maps are created when you set up device allocation. A rudimentary device_maps file is created by bsmconv when the BSM is enabled. This initial device_maps file should be used only as a starting point. You can then augment and customize the device_maps file for your site.

The device_maps file defines the device-special file mappings for each device, which in many cases is not intuitive. This file allows various programs to discover which device-special files map to which devices. You can use the dminfo command, for example, to retrieve the device name, the device type, and the device-special files to specify when you set up an allocatable device. The dminfo command uses the device_maps file to report this information.

Each device is represented by a one-line entry of the form:

device-name:device-type:device-list

Lines in the device_maps file can end with a backslash (\) to continue an entry on the next line. Comments can also be included. A “#” makes a comment out of all subsequent text until the next newline not immediately preceded by a backslash. Leading and trailing blanks are allowed in any field.

device-name

Specifies the name of the device, for example st0, fd0, or audio. The device name that is specified here must correspond to the name of the lock file that is used in the /etc/security/dev directory.

device-type

Specifies the generic device type (which is the name for the class of devices, such as st, fd, audio). The device-type field logically groups related devices.

device-list

Lists of the device-special files that are associated with the physical device. The device-list must contain all of the special files that allow access to a particular device. If the list is incomplete, a malevolent user can still obtain or modify private information. Valid entries for the device-list field are either the real device files located under /devices or the symbolic links that are in /dev. The symbolic links in the /dev directory are provided for binary compatibility.

The following is an example of a device_maps file entries for SCSI tape st0 and diskette fd0.

fd0:\
	fd:\
	/dev/fd0 /dev/fd0a /dev/fd0b /dev/rfd0 /dev/rfd0a /dev/rfd0b:\
					.
					.
					.
st0:\
	st:\
	/dev/rst0 /dev/rst8 /dev/rst16 /dev/nrst0 /dev/nrst8 /dev/nrst16:\