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TUTORIALS AND EXAMPLES ON ENCRYPTING

Encrypt menu

How to provide or hunt text files ?

Safety checks in encryption relating to the sizes of files

Tutorials and examples of encryption (General Definition)

Tutorials for message 70005

Tutorials for message 70001

How to simple encrypt any file ?

What is an interior security number (ISN) ?

How to choose a proper ISN ?

Double Encrypting

Cross Encrypting

Encrypting files other than text (media files)

HOW TO PROVIDE OR HUNT TEXT FILES ?

This program works with text files for encrypting, you have to do one of the following in order to obtain these files;

1_Write some text files yourself like; stories, scientific papers, nonsense poems etc.

This is the most difficult method, unless you are a prolific author/writer

2_Use some text files found in your office or home.

May be feasible, but it is quite difficult to find text files anytime you want.

3_Scan some specific pages of certain books at two terminals and then read them by OCR software.

This seems quite a good idea, provided that you have extra high quality scanning equipment and OCR software, to be able to convert a book page to a text file, without any error. Hasn't been tried in here since we are lacking such superb tools. This may be worth trying in some well equipped embassies, ministries and IA's. where some libraries also exist. In such a situation, the tables you see down below will constitute; the names of the books, publishers, page numbers, publishing dates etc.

4_Use someone else's prepared text files in the net.

Seems the easiest and best way to provide text files. Sometimes decryption may fail by this method, because one of the sites in the keyset is updated or deleted by the site owner while you are uninformed, anyhow the probability of such a condition may not be so high; there are some text files in internet which are older than five years.

To scan for someone else's prepared text files from

internet, open google advanced search and fill in the

table exactly as following, then click Google Search.

If you do this operation, you'll find millions of files suitable for your purposes, select four of them as a keyset.

WHAT IS AN INTERIOR SECURITY NUMBER (ISN) ?

Eight digit ISN may be thought as a password which provides the following utilities:

A-Prevents trial attacks on internet addresses, the probability for each keyset tried to be correct is about; 1/108

B-It forces the internet addresses to be entered in correct order, e.g; if you enter key3 instead of key1, it wont work. You should enter the keys, just in correct order --> key1, key2, key3, key4. This provides an additional security against "trial and error" makers, since they have to make their trials in correct order.

C-It provides a central organization to send private messages to its particular members. Other members, who are not involved in a special operation and hence don't know the ISN cannot read the messages.

D-For each unique ISN and four address keyset, there corresponds a single OTP. The ISN is not concealed in the encrypted file, instead it is created by modular arithmetic and is completely safe from being detected.

HOW TO CHOOSE A PROPER ISN ?

ISN is like an eight digit telephone number and is distributed by a central authority to its members, such as the head of ministry of foreign affairs. Memorize your ISN and never tell it to anyone. If you are involved in some transfer of messages to someone else, then you have to learn their ISN by official permission and encrypt a message accordingly.

Some DO NOT 's while choosing a Proper ISN

1- DO NOT use all-same-digit numbers like (44444444, 77777777 etc); The program works well, but this will breach the security condition stated above in term B

2-DO NOT use palindromic-numbers. ( The numbers which read the same, when taken from reverse direction like 12344321, 73211237 ). The program works well, but this will also breach the security condition stated above in term B

3- DO NOT use first eight digits of some mathematical constants like (31415926), Your adversaries may guess.

4- DO NOT use some numbers that carries relation to (date of birth, social security number etc.), Your adversaries may guess.

SAFETY CHECKS IN ENCRYPTION RELATING TO THE SIZES OF FILES

There is a simple formula for the shortest size of a key in a keyset, which is given by the following;

Sf stands for a safety factor which takes care of unforeseen effects in encryption. We'll take; S f =1.40 for our text files. Factor S f changes considerably from file to file, therefore don't bound to this value so much.

Shortest Size of Key = SSK

Message Size (Size of Message file to be encrypted) = MS

SSK > ( 8 . MS ) . Sf

ATTENTION: The sizes of other keys in the keyset are NOT important, since the program aligns itself to the size of the Shortest Size of Key (SSK) in the keyset

TUTORIALS AND EXAMPLES OF ENCRYPTION (GENERAL DEFINITION)

The browser used in all these computations is IE 6.0. If you use other browsers OR or a different version of the same browser, it won't work. The Operating System used, is not so important as far as the program can be executed,

To provide additional synchronization, all of the contributing partners should perform the following checks and alignments on their browsers:

A -Control: Help > About Internet Explorer > read the version number. If it is NOT 6.0, then don't commence.

B -Align: Tools > Internet Options > Advanced > Restore Defaults > Apply > OK.

C -Align: View > Encoding > check "Western European (ISO)". ("Auto Select" option should be UNchecked)

Use the "Western European (ISO)" option during all the savings, and state this condition on all of the tables.

TUTORIAL FOR MESSAGE 70005

Download Message 70005 to C:\windows\desktop to be used as a subject in this tutorial.

Save all the keys into the directory (C:\windows\desktop\keys 70005)
internal security number ISN: 19453208

### name of file for saving | ### file web address ### (click to open ) | ### Viewing and Encoding during saving | ### Saving type of file
key1(70005).txt | site1 | Western European (ISO) | Text File (*.txt)
key2(70005).txt | site2 | Western European (ISO) | Text File (*.txt)
key3(70005).txt | site3 | Western European (ISO) | Text File (*.txt)
key4(70005).txt | site4 | Western European (ISO) | Text File (*.txt)

How to save keys: Click to site1 or site2 or site3 or site4; then from file menu at top left, choose save as; complete the Save Web Page prompt as shown in the tables, to the directories stated at the first cell of their tables.

The usage of keys and encrypted files for decryption are described at the end of this section.

Check for Shortest Size of Key (SSK);

Message Size = MS = 7955 byte, Sf =1.40

8*MS*Sf = 89096 byte

shortest key (SSK) is key2 in this case, which is equal to 90946 byte

therefore SSK > ( 8 . MS ) . S f OK

TUTORIAL FOR MESSAGE 70001

Download Message 70001 to C:\windows\desktop to be used as a subject in this tutorial.

Save all the keys into the directory (C:\windows\desktop\keys 70001)
internal security number ISN: 19453208

### name of file for saving | ### file web address ### (click to open ) | ### Viewing and Encoding during saving | ### Saving type of file
key1(70001).txt | site1 | Western European (ISO) | Text File (*.txt)
key2(70001).txt | site2 | Western European (ISO) | Text File (*.txt)
key3(70001).txt | site3 | Western European (ISO) | Text File (*.txt)
key4(70001).txt | site4 | Western European (ISO) | Text File (*.txt)

How to save keys: Click to site1 or site2 or site3 or site4; then from file menu at top left, choose save as; complete the Save Web Page prompt as shown in the tables, to the directories stated at the first cell of their tables.

The usage of keys and encrypted files for decryption are described at the end of this section.

Check for Shortest Size of Key (SSK);

Message Size = MS = 4828 bytes, Sf =1.40

8*MS*Sf = 54073 bytes

shortest key (SSK) is key2 in this case, which is equal to 54718 bytes

therefore SSK > ( 8 . MS ) . Sf OK

HOW TO SIMPLE ENCRYPT ANY FILE ?

Suppose you have a "C:\windows\desktop\keys 70005" directory. In this directory, according to the definitions and procedures told in previous article there should be the following files.

key1(70005).txt

key2(70005).txt

key3(70005).txt

key4(70005).txt

and on your desktop C:\windows\desktop you'll have the file ;

message(70005).txt (the official text file to be encrypted)

Do the following step by step for simple Encryption;

Open the PracticalOTP program by double clicking its icon on the desktop.

1_ Click Encrypt menu.

2_ Enter the eight digit Internal security number.

3_ Click key1.txt, pass to ,C:\windows\desktop\keys 70005 double click key1(70005).txt to enter the related first key.

4_ Click key2.txt, double click key2(70005).txt to enter the related second key.

5_ Click key3.txt, double click key3(70005).txt to enter the related third key.

6_ Click key4.txt, double click key4(70005).txt to enter the related fourth key.

7_ Click compute main key button,

Some time will pass for computing the main key, the working time will depend on the size of the key1.txt, key2.txt, key3.txt, key4.txt. After performing this operation, You'll see a cursor is blinking at the top left of the message space, which indicates that the text message is ready to be entered.

8_ Open message(70005).txt file on your desktop (the text file which has to be encrypted). Click: Select All > Copy, from edit menu, come into Practical(OTP)'s message section and do right click > Paste operation from your mouse. The copied text, will be pasted into the blank area. At this stage you don't have to make any additional operation, such as correcting the text section and trying to justifying the text. Just leave the text as it is and do nothing to change the appearance.

Sometimes the following condition occurs; The text in the message section falls short, that is some of the text is not pasted into the blank area and you see that a sentence is not completed at the end. This means that you have chosen the shortest key too small. Safety check is breached. Under this condition immediately exit the program and return to choosing the keyset, this time choose a smallest key which is about thirty percent greater than its former value and commence the cycle from beginning.

9_ Click compute Encrypt.enc button,

Some time will pass for computing the Encrypt.enc file, the working time will depend on the size of the contributing files.

10_ encrypt.enc file will always be saved into the C:\windows\desktop\keys 70005 directory, automatically.

11_ Click Exit and exit the practicalOTP program.

12_ Immediately go to the C:\windows\desktop\keys 70005 directory and by renaming function of windows, change the name of encrypt.enc to a new name; encrypt(70005).enc.

At this stage, you may zip encrypt(70005).enc by WinZip program. Send this zipped file to the receiver from open channels. Make a similar table like the ones shown above and inform your partner by some method which has been prearranged by the agreement of two sides in advance. This method of informing the other side about the keyset, is left to your own imagination, but should be a secret method anyhow.

DOUBLE ENCRYPTING

Suppose Bob wants to send a message to Alice (by double encrypting);

While browsing, he selects a four text file set; key_small _1.txt, key_small _2.txt, key_small _3.txt, key_small _4.txt (as recommended from different language of texts), from their corresponding web addresses; encrypt top_secret.txt (plain text) by using the official ISN of his partner (Alice). Now he has top_secret_small.enc, as the first encryption file.

Then he selects another four text file set key_big _1.txt, key_big _2.txt, key_big _3.txt, key_big _4.txt (as recommended from different language of texts), from their corresponding web addresses; encrypt top_secret_small.enc by using the official ISN of himself (Bob) this time. Now he has top_secret_big.enc as a second encryption file. He has double encrypted a message by using the official ISN's of his partner (Alice) and himself (Bob)

Bob sends top_secret_big.enc file to his partner by open channels and transfers all of the related txt addresses by some predetermined internet links (since they know each others ISN, the transfer is only realized on keysets); so that Alice can be able to perform just the reverse of the operations he had made to decrypt the message.

The application of this method will greatly reduce the "pattern generating tendencies", causing from the utilization of "linguistic type of documents" in the processes.

CROSS ENCRYPTING

Suppose Bob wants to send a message to Alice (by cross encrypting);

1_ While browsing, he selects four Internet sites, which contain text (txt) files; file_GR11.txt, file_GR12.txt, file_GR13.txt, file_GR14.txt

He passes (crosses) them from TRNG menu to get; crossed1.rnd

2_ While browsing, he selects four Internet sites, which contain text (txt) files; file_GR21.txt, file_GR22.txt, file_GR23.txt, file_GR24.txt

He passes (crosses) them from TRNG menu to get; crossed2.rnd

3_ While browsing, he selects four Internet sites, which contain text (txt) files; file_GR31.txt, file_GR32.txt, file_GR33.txt, file_GR34.txt

He passes (crosses) them from TRNG menu to get; crossed3.rnd

4_ While browsing, he selects four Internet sites, which contain text (txt) files; file_GR41.txt, file_GR42.txt, file_GR43.txt, file_GR44.txt

He passes (crosses) them from TRNG menu to get; crossed4.rnd

Bob renames the crossed files from DOS prompt, as following;

crossed1.rnd ---> key1.txt

crossed2.rnd ---> key2.txt

crossed3.rnd ---> key3.txt

crossed4.rnd ---> key4.txt

Then, Bob Passes to Encrypt menu:

He uses these crossed files to encrypt the plaintext; top_secret.txt, to obtain top_secret.enc . By doing this operation, he is getting rid of pattern carrying linguistic type of text files used as keyfiles and utilizes somewhat more entropy containing crossed files (random keyfiles consisting from hexadecimal characters) in encrypting operation.

Bob sends top_secret.enc file to his partner Alice, by open channels and transfers all of the related txt addresses by some predetermined internet links, so that Alice can be able to perform just the reverse of the operations he had made to decrypt the message.

ENCRYPTING FILES OTHER THAN TEXT (Media Files)

We are trying to extend this system to a general global communication transmission in encrypted forms. The method is very easy to apply.

This system can be used to encrypt or decrypt files other than text files (such as bmp, wav, gif, mp3 etc.). All you have to do is to to find a set of many text based internet sites in four number groups, then click "tru ran num gen" menu, transform the set of list to a single random file mainkey.rnd (as an example), then open Prof Marsaglia's asc2bin.exe which may be found in his diehard battery set, using the tool asc2bin.exe convert the mainkey.rnd to mainkey.32 (the binary form of mainkey.rnd).

Now you have a binary form of random file, mainkey.32 which may be used to XOR any non-text file (bmp, wav, gif, mp3). The XOR'ing is done by the tool of Prof Marsaglia's diehard battery, The meld.exe (using the "X" choice during the process). After the encyption by XOR function using the meld.exe; there is the encrypted file encrypt.32 which you can send by open channels. The Decryption will be just the opposite; this time meld encrypt.32 file with mainkey.32 file. Give the name of the output file as (decrypt.bmp, decrypt.wav, decrypt.gif or decrypt. mp3)

The encrypted file encrypt.32 cannot be listened or edited by any sound or graphic editor. The webaddress list of set which is used to obtain the mainkey.rnd and hence mainkey.32, may be sent to your partners by secret channels, so that they perform just the same procedures to retrieve the original sound or graphic file.

We have tried these operations on (bmp, wav, gif, mp3) type of files and success was 100%, however if you do encounter some difficulty in applying the method, you can drop an email to us from the address practicalOTP@hotmail.com

name of the mediakey to download. (Name of the first file in the meld.exe tool, while executing)* | Name of the general keyfile The keyfile that opens all of the mediakeys. (Name of the second file in the meld.exe tool while executing)* | Name of the tool to XOR the mediakeys and keyfile. (May be found in Diehard battery set) | (Name of the output file in the meld.exe tool while executing)* You will give the name | Size of the final Decrypted file (Kb)
Download from internet site | Download from internet site | meld.exe | dec_bmp.bmp | 464
Download from internet site | Download from internet site | meld.exe | dec_gif.gif | 160
Download from internet site | Download from internet site | meld.exe | dec_jpg.jpg | 112
Download from internet site | Download from internet site | meld.exe | dec_mp3.mp3 | 624
Download from internet site | Download from internet site | meld.exe | dec_wav.wav | 624

While executing the meld.exe, there will be some prompts that you should fill in the tool, these are the first file, the second file and the name of the output file respectively. Always choose the "X" choice for melding, when asked in the tool.*

How to obtain the general mediakey.32 file;

First obtain the mediakey.rnd file by the methods told in the section "tru ran num gen / How to create a TRNG file" . Then use the tool, asc2bin.exe (which may be found in the Diehard battery set) to convert the asci file to a binary file, mediakey.32

How to obtain the encrypted files enc_XXX.32 which are seen in the first column of the above table;

XOR any media file (bmp, gif, jpg, mp3, wav extension), with mediakey.32 keyfile; by using the meld.exe tool of Diehard battery set (Just the opposite operation you had performed, when you were working with the tableset at above).

The mediakey.32 keyfile should be a little longer than the media file which has to be encrypted, or else it will encrypt as long as it can do and the rest of the media file will be left un-encrypted. In such a case the final decrypted media file dec_XXX.32 will be shorter than the original one. That's all you have to think about the lengths of the keyfiles and encrypted files.