S E C U R E


     SECURE is a software-only password security system that will 
prevent unauthorized users without the correct password to gain 
access to an IBM PC or compatible microcomputer.

     The SECURE system consists of SECURE.SYS, the password 
device driver, and SYSTALL.COM, the installation program, which 
will be discussed later.

     SECURE simply prevents the computer from loading the 
operating system and executing user-commands.  On floppy-disk 
based machines, SECURE should be installed on all disks at a 
particular workstation that might be used as a boot disk.  The 
original operating system diskettes should be locked away.  For 
fixed-disk based machines, SECURE must be installed on the fixed-
disk in the root directory, and should also be installed on any 
floppy diskettes kept at the workstation as the protection can be 
defeated by simply booting the computer from a non-protected 
diskette.


     The SECURE device driver is a skeleton device driver file 
compatible with MS/PC-DOS versions 2.00 or above.  It is 
configured as a character device, but no I/O functions are 
implemented.  The INIT code is the only valid section in the 
device interrupt handler.  The INIT code is executed when the 
driver is first loaded and prompts the user for an eight 
character password.  The user is given three attempts to enter 
the correct password before the program quits and enters IBM ROM 
Cassette BASIC (Note: On most IBM compatibles, the user is 
prompted to insert a system disk and reboot, as the machine 
contains no ROM BASIC.).

     Once the correct password has been entered, DOS finishes 
loading from the boot disk, and all carries on as usual.

     For SECURE to work properly, the root directory of the boot 
disk must have a CONFIG.SYS file containing the line 
'DEVICE = SECURE.SYS'.  SECURE.SYS must also be in the root 
directory of the boot disk.  SECURE.SYS can later be moved to
a subdirectory by simply editing the CONFIG.SYS file to reflect
the change.

     The password is included in the SECURE.SYS file, but is 
encrypted, so that a simple DEBUG dump of the file will not 
reveal it.  The password can be changed as often as the user 
wishes using the SYSTALL Installation utility.

     The SYSTALL.COM program is the only means by which the user 
can change the password in the SECURE program.  If the password 
is forgotten or misplaced, the only recourse is to install 
another one.  AN OLD PASSWORD CANNOT BE RECOVERED, ONLY REPLACED!


     To use SYSTALL from the direct mode, simply type SYSTALL at 
the DOS prompt.  Make sure that both SYSTALL.COM and SECURE.SYS 
are present in the current directory of the default drive.

     The SYSTALL program will prompt you for the Target drive 
which is the disk drive to which you want to copy the necessary 
files.  The only valid responses are A or B or C since, because 
of the PC's architecture, C is the highest available bootable 
device.

     SYSTALL will then ask for the password.  It is entered as 
eight characters or numbers or symbols followed by a carriage 
return.  The password must be at least eight characters in 
length.  If less than eight are entered, the user is asked to re-
enter the password.  If more than eight are entered, all 
characters after the eighth are ignored.  There may be NO 
leading, embedded, or trailing spaces.  Either upper- or lower-
case letters may be entered, as all characters are converted to 
upper-case before they are encrypted.

     SYSTALL will encrypt the password, copy SECURE.SYS from the
default drive and directory into the target drive's root directory,
patching the password at the same time.  Also, CONFIG.SYS is edited
to append the line "DEVICE = SECURE.SYS".  If no CONFIG.SYS file 
exists, it is created.

     SYSTALL can also be used from the batch-mode by entering the 
target drive and password on the command line with the program 
name:

SYSTALL C BLUEBOOK

would install SECURE on drive C with the password BLUEBOOK.

systall a michelle

would install SECURE on drive A with the password MICHELLE (note 
the successful use of lowercase letters).


     FINAL NOTES:

     Upon typing in the password at the prompt during boot-up, no
mistakes can be made, as there is no editing capability built into
the SECURE driver.