Shareware Overload/ShartewareOverload.cdr/busi/pcode153.zip/PC-CODE1.DOC

Text File | 1984-06-14 | 9KB | 226 lines

                     <<< PC-CODE1 >>>



To begin execution of PC-CODE1 or PC-CODE2, just type these names
in PC DOS or type PC-MENU. For example:  "A> PC-MENU "


PC-CODE1 is intended to encode/decode files only. It does this
thru a process known as byte super-encipherment. This means that
each character (or bit) of plain text (uncoded text) is both scrambled
(transposed) as well as substituted for some random "other"
character.

Keys may Optionally be Loaded or Saved to a FILE. The data format
of such a file is 25 KEY numbers (between 1 & 2,147,483,646)
each separated by A Carriage Return (on separate lines); And
finally a 26th line of required Comment/Remark Information.
An example of a key file is "SAMPLE.KEY". You can display
this file by typing one of the following in DOS.

     A> TYPE SAMPLE.KEY

           <OR>

     A> COPY SAMPLE.KEY LPT1:


A key file may be generated in PC DOS by the Following:

     A> COPY CON: MYKEY.KEY
        2028841238
        156091745
        1551901393
        590357944
        ..........
        ..........     [a total of 25 numbers]
        ..........
        109941534
        2110010604
        * This is my remarks 06/06/84 7:56 PM  PC-CODE1 V1.53
        ^Z  {Ctrl-Z}  {ENTER}

If a key file is not used the following discussion applies:
There are two levels of security "LOW" and "HIGH". If you
elect the LOW level you will only have to enter 7 key
(SEED) numbers or in the case of alphanumeric keys 7
passwords of 5 or more characters. Actually, the longer
the passwords - the better. An Ideal password length would
seven passwords of 8 characters each.


If you elect HIGH security be prepared to enter up to 25
numbers between 1 and 2,147,483,646; or a minimum of 180
characters of alphanumeric passwords. It is best, the first
time thru to elect LOW security for testing purposes.
Why so many characters are required in the HIGH ALPHA mode security
is due to the additional insecurity of letters/words/phrases
and that the Randomizing (hashing) routine requires 6 characters
to generate a uniformly random Number (used internally). If the
users' alphanumeric passwords were perfectfully random and
all 256 possible characters could be typed at a 47 key keybroad,
there would only be a need for 4 characters to generate this number.

The user must provide a series of keys (a minimum of 7) which
may either be numeric (i.e. characters "0123456789") or
alphanumeric which includes any character on your IBM PC
keybroad. This includes alphabetics, numerics, and special
symbols like  "!@#$%^&*()=+?:.<>[]~{}"  and so forth.
Each of these keys should be chosen at random, and each
should be different. For alphanumeric keys, the following
is a good example:


       GOOD KEY  ---> "Z$x!Un{y%C2&>"

       BAD KEY   ---> "ENGLISH WORDS"


It is very poor to use anything that could be found in a
dictionary or encyclopedia for a key.


For Numeric keys, the best choices might numbers chosen
randomly from a telephone book or a serial numbers on a
Dollar bill. It is considered unprofessional to use numbers
like - you birth date; social security number; or Military
service numbers. Of course, for testing numbers like 1,2,3,4,
5,6,7 are great to test out the programs. Example of keys:


       GOOD KEYS ---> 1095572    6712950   4007173   935506

       BAD KEYS  ---> 1          1         84        0

       INVALID   ---> 1,000,000  7.712355  -679811   6566710-


Note that it is Invalid to include commas within key numbers.
Also, note that numeric keys are positive Integers greater
than zero. For best results, numeric keys should be 6 digits
at least.


Input and output must be to and from a valid IBM PC file.
The same file may be used for both input and output for PC-CODE1
only. This is however, not recommended. Input/output must NOT
the Console or Printer. PC-CODE1 supports only File Input/Output.


Never forget your keys, or lose them as it is impossible to
decipher the outputed code. Also, never attempt to encode
and decode data with different version of these programs.


PC-CODE1 will successfully encipher/decipher Binary files
such as those with ".COM" and ".EXE" file extensions.
PC-CODE1 works on files as sectors of 512 characters and
generates binary codes using all 256 possible 8-bit characters
(000 thru 255). The Encoded output of PC-CODE1 is not suitable
for printing, since many of these binary characters will drive
your printer bananas (hence only files in and out). PC-CODE1
output files are rounded up to the next 512 byte sector
boundary. This will not distort you data, since all end of file
marks and carriage returns/line feeds are successfully also
encoded and decoded. Padding of Nulls (hexadecimal 00) are
sometimes added to the end of files for this rounding.
On decoding a file, these padding characters usually are
transparent due to the normal end-of-file character following
them; hence they are not seen.


If you use this routine for Communications via some serial Port
it is best to change the the binary output code to hexadecimal
characters (two hexs characters per binary character).


The pseudo-random number generator used has a period of greater
than 1.98E+233 or 1.98 times ten raised to the 233th power.
By comparison the National Bureau of Standards DES algorithm
has a period less than 7.21E+16 (or about 2 to the 56th power).
The PC-CODE algorithm uses a MINIMUM of 775 bits (96 characters).
It is likely that systems based on 8 or 16 characters are not
very secure based on todays computer hardware/software technology.
To evaluate PC-CODE would be to visualize a Safe with 25 dials -
each with graduations between 1 and 2,147,483,646. A typical
combination office safe might have 4 numbers each between 1 and 100.


The Programs PC-CODE1 and PC-CODE2 are meant to be compiled
by IBM's BASCOM BASIC Compiler and NOT for IBM's BASICA/BASIC.
The Micro Ware Corporation also makes a 8087 Compiler called
87BASIC (or 87BASCOM) which will increase execution speeds
many many times (maybe 11 times faster). In either case,
when these programs are compiled the "O", "T", & "N" options
should be specified. For example:    B> A:BASCOM/O/T/N
PC-CODE1 source code contains no BASICA line numbers except
when required by a GOTO or GOSUB statement.

The ".EXE" files provided have been compiled by the 8088 version
or IBM BASCOM. Since, double precision floating point is used
in the pseudo-random algorithm the 8087 compiler is a must for
timely and rapid execution; especially for large files.


With the introduction of version 1.53 of PC-CODE 1 & 2, an
cryptologic audit trail has been added. What this means is that
the programs checks itself statistically. It tabulates, what
random characters it generates. It analyzes the combination of
keys selected by the user. As far as character counts don't expect
to get exactly the same number of counts for each character (0-255).
However, as more and more characters are encoded, the counts should
get closer to even. The program should however generate every possible
character for moderate sized files. Random key selection can improve
all of the above factors. The user may specify a file to store these
statistics or print them (LPT1:). If a file is not specified and the
user merely presses ENTER, then the default file generated will be
called "PC-STAT1.LOG" (for PC-CODE1) or "PC-STAT2.LOG" (for PC-CODE2).
A sample of each of these has been provided on the distribution
diskette.   A> COPY PC-STAT1.LOG  LPT1:

Starting with version V1.53 PC-CODE1 can do bit scrambling as well
character scrambling. Scrambling (transposition) is done in
blocks. Character scrambling is done in blocks of 128 characters
while bit scrambling is done in blocks of 1024 bits. In bit mode, trans-
position is over a entire block of 1024 bits (128 bytes). Any character
and any bit within any character may be exchanged with another
bit anywhere in the 1024 bit block. The National Bureau of Standards
DES algorithm deals with bit blocks of only 64 bits.

Bitwise transposition is very costly - but is also the most secure
thing in existence. Character mode creates a new pattern or
random "deal" every 4 blocks to economize on overhead. Bit mode
does the same, but every 32 blocks of code. Proportional, this
the same ratio for both methods. This does not compromise security
because of the exponential nature of binary blocks.

A listing of all Documentation files may obtained by typing in PC-DOS

           A> DIR *.DOC

Also typing "PC-HELP" will use some usefull documentation tips.

           A> PC-HELP


These programs have been copyrighted in the Public Domain and
authored by:


            Richard Nolen Colvard
            1745 Winona Blvd, Apt #21
            Los Angeles, Calif. 90027


 The above material and PC-CODE software contains no material
 relating to the National Security of the United States of
 America as defined by the United States Code. However, distribution
 to Foreign Nations or Agents is prohibited by the directives of
 the National Security Agency. (NOT FOR EXPORT).

 Both the Author and/or Distributor assume no liability for
 any lost of data or business as a result of usage of the
 PC-CODE programs; which are Public Domain Freeware.