AngelCrypt
User's Manual
Version 1.0

angel <input> [flag]

Where:

     <input> Can be any file, whose attribute is normal or archive
             but not hidden, system, and readonly files. Also accepts 
             wildcards like *, *.*, *.exe, f*.*, etc, directory name
             or path

             The system cannot read or delete hidden, system, readonly,
             or zero length files. In case the input file cannot be 
             read, the system will terminate prematurely, modify the 
             attribute of the file so that the system can accept it.  

             Wildcards can be of any forms, the system can accept
             also path or directory name only.

     [flag]  There is only one flag, -d means delete the original 
             input file after encryption or decryption. The default
             is to retain the original input file.

Encryption & Decryption:

The system can detect whether the file is encrypted or not. The output 
filename is the same as the input filename plus a .jrc extension.  Removing 
the .jrc extension will not harm the file, the system can still decrypt the 
encrypted file. Remember not to delete the original extension because the 
system cannot restore it.  If the size of the file to be encrypted/decrypted
is zero, the system will not perform any operation to it, it will not touch
the file.

Key

The system can accept keys up to 1024 bytes of characters (8192 bits), 
this means that the system can accept phrases or words as a key.  In entering
the key, the system will ask twice when it performs encryption, once for
decryption. the system can detect if the key is valid or not.  All keyboard 
keys are valid key character so backspace or delete are also a part of the key.

Input

The system can accept path, full path, filename or wildcard as the 
input or first argument.  The system will not do anything if the
input is invalid. Below are examples of different usage for the system

a) Encrypt all the file in the xdir directory

   this assume that the system will be executed on the root directory
   and the xdir is on the root.

   angel xdir -d or angel xdir\*.* or angel c:\xdir\*

b) Encrypt all file with an extension of .txt

   angel *.txt or angel d:\xdir\*.txt
   
c) Encrypt all files and directories in the jet directory

   angel jet -d or angel d:\jet\*.* or angel d:\jet\* or angel d:\jet 
   or angel d:\jet\

d) Encrypt only one file

   angel readme.txt -d or angel readme.txt

If the input for the system is only the directory name, it will encrypt/decrypt
all files and directories under the said directory.  The system doesn't perform 
operation to any file with a size of zero.

!!REMEMBER!!
Backup all your files before doing some operation involving this application. 
(Please read the disclaimer before using this software).

About AngelCrypt

AngelCrypt is a private key cryptosystem that can encrypt or decrypt 
any kind of file.  The security of this system is handled by the 
stream RC4 compatible algorithm taken from cypherpunk and MD5 Message
Digest Algorithm.

AngelCrypt uses the Alleged RC4, a RC4 compatible algorithm release
in the internet thru cypherpunks and the MD5 RSA Data Security, Inc. 
Message Digest Algorithm.

RC4 is a variable key size stream cipher developed by Ron Rivest of
RSA Data Security Inc. in 1987. It was a proprietary algorithm and the
details were only available after signing a nondisclosure agreement.
It was September, 1994 when someone posted a source code to the 
Cypherpunks mailing list, the author is unknown and it quickly spread
to the Usenet newsgroup sci.crypt and also thru Internet ftp sites all
around the world. Readers who have a legal copies of the RC4 confirmed
that the algorithm is indeed compatible to the RC4.  RSA still claims
that the algorithm is still a trade secret, but it was already public,
discussed and dissected on Usenet.  Today the algorithm is taught in 
cryptography courses, distributed at conferences and already included
on most encryption softwares packages.
(see Applied Cryptography by Bruce Schneier, p.397).

AngelCrypt Written by Jose Mari Reyes
Copyright(C)2000, Jose Mari Reyes
email:jet_reyes@jetemail.net
  web:www.angelfire.com/co2/xtechnica
Manila, Philippines

RC4 & MD5, Copyright (C) 1990, RSA Data Security, Inc. All rights reserved. 
Alleged RC4 Algorithm taken from cypherpunks.