Current Shareware 1994 January/SHAR194.ISO/virus/drkr038.zip/DRKR.DOX

Text File | 1993-07-14 | 6KB | 103 lines

DRKR.DOX for DRKR.EXE

Dr. Krypton Documentation

Dr. Krypton file encryptor was written in QuickBASIC 4.5 by Dave Byter on 13
Feb 93.  Friday the Thirteenth came a day late this month.

Dr. Krypton will encrypt and decrypt any file.  By a special act of magic,
encryption and decryption are exactly the same process.  Encryption twice (with
the same personal encryption numbers!) will give you back your original file.

From the friendly DOS prompt;-> DRKR filename.ext pen1 [pen2 [pen3 [etc]]]

where pen1, pen2, etc are one to ten personal encryption numbers.  A personal
encryption number is a positive single precision QuickBASIC number, which must
be between 1.401298E-45 and 3.402823E+38.  If you use exponential notation,
there must be no embedded spaces (1.401298 E-45 is illegal).  In decimal the
limits are 0.000000000000000000000000000000000000000000001401298 and
3402823000000000000000000000000000000.  In American English, that's between one
plus quattuodecillionth and three hundred plus undecillion.  Only the first
seven digits count, but you should play it safe with the eighth digit.

This is not as many different pens as it first appears, since only the first 7½
digits really count.  There are only 4 bytes, or 256^4, or ≈4.3 billion
choices.  But if you use ten pens, there will be 256^4^10/10!, or ≈5.9E+89
choices.  This is somewhat more than the number of elementary particles in the
known Universe, which is sufficient for my purposes.  If it is not for yours,
then you can re-encrypt.  It is irrelevant whether the pens occur in the same
run or in successive runs, and their order is also irrelevant.  Your security
is more likely to be broken by you leaving a written record of your pens or by
choosing easily remembered numbers such as Plank's Constant or Heinlein's
number of alternative universes.

Note that I can supply a stealth version which does not echo your pens to the
screen.  This is useful if you are in the sort of place where someone might be
looking over your shoulder.

Note that DRKR with no arguments will give you instructions, so that you won't
need to print or to keep looking at this file.

You may choose your desired level of security.  Dr. Krypton uses the
QuickBASIC pseudorandom number generator, which is seeded with your personal
encryption number.  Given the resources of the Federal Bureau of Investigation,
one could try every seed, and look for any resulting plaintext.  With two
personal encryption numbers, you would not know when you got one of them
right.  It would require the resources of both the Federal Burro of
Investigation and the Central Intelligence Agency to break your encryption.
With three encryptions, the combined talents of the FBI, CIA, and the National
Security Service would be necessary to break your security.  With four
encryptions, they would run out of taxpayers.  And you can specify up to ten
personal encryption numbers.

If you decrypt with the wrong pen, just re-encrypt with the same wrong pen and
you will be back where you started.  But you should have copied your file and
decrypted the backup.  There is no one to rescue you.

Dr. Krypton does not record your pens in any form anywhere.  It would
compromise security to do so.  How you choose to remember your pens is your
problem.  If you forget your pens, I offer a data recovery service.  For
registered users, data recovery is $1 per byte per pen, payable by certified
check or money order.  For unregistered users, data recovery is $10 per byte
per pen, payable in unmarked Federal Reserve Notes of small denominations.

When using multiple personal encryption numbers, the order of the pens is
irrelevant.  Just make sure that you have the right numbers!

Dr. Krypton overwrites and destroys the file which it encrypts.  Should there
be a power failure or other interruption, you will have a file which is both
unreadable and undecryptable.  You might want to copy your file to a backup
before encryption.  But be forewarned, DOS does not destroy a deleted file
until it is overwritten.  You can destroy the file by copying the encrypted
file to the backup file when you are confident that your file has been properly
encrypted.

You should also be aware that DOS does not overwrite the unused space on the
last cluster written by a file.  This will result in up to 4047 bytes
(depending on file length and disk cluster size) of the previous file readable
with a simple sector reader.  If you are concerned about security, be sure that
you overwrite a sensitive file with a cover file at least four kilobytes longer
than the deleted file.  Then delete the overwrite file.

Registration fee is $10 for single user, $25 for site license of less than five
users, $50 for less than twenty users, and $100 for more than nineteen users.
A registration form DRKR.REG is included for your convenience.

Register this software by sending your check (payable to CAVE, Inc) to Dave
Beiter, CAVE Inc, ½ Fast Road, Ritner, KY 42639.  Phone [phone].  Tell me
where and when you received your copy, and your preferred disk size.  You will
receive the latest version of Dr.  Krypton (with source code).  You may also
order Survey Land Yourself and Deed Plat for $5 each.

Files included in Dr. Krypton are:

!              The prompt file when extracting DRKRYPTN.EXE (LHA file)
DRKR.EXE       The Dr. Krypton encryption/decryption program.
DRKR6.666      The QuickBASIC 4.5 source code for registered users.
DRKR.DOX       The complete documentation file.
DRKR.LIC       The License Agreement for use of Dr. Krypton.
DRKR.REG       Handy registration form.
TEST.5         A test file. Decrypt with pen = 0.5
DESCRIPT.DKR   Suggested catalog description & category for Dr. Krypton.
DRKRYPTN.DOX   This file.  External documentation for DRKRYPTN.EXE