"In the beginning was the Word...". John 1:1

 

Stelin is an open source tool that makes possible to hide "information" into digital text. Stelin generates different stego-texts automatically, stego-texts with syntactic and semantic sense. Stelin is based on N-Gram statistics from training natural texts. Usefull for different languages, for example, Spanish and English.

Downloads

[March 2010]. Stelin v0.1 beta [Download-JAR 18KB] [LICENSE]

+-+-+-+-+-+-+-+-+ SHA-256 [be0446d260153b536028335df9740c3f7f88419cc3469d6e207e501f140f6e02]

+-+-+-+-+-+-+-+-+ RIPEMD-160 [9f148c1260add4367101ab8d3c3021e6cf8e41a6]

Manual

Examples of hidden data with 9 order:

#> java -jar stelin.jar -h -9 trainingText.txt fileWithSecretMessage.txt myPassword_AEf23te1 fileWithStegoTextOut

Examples of recover secret message with 9 order:

#> java -jar stelin.jar -u -9 trainingText.txt fileToSaveSecretMessage.txt myPassword_AEf23te1 fileWithStegoTextOut

Examples of hidden data with 8 order and creating template file:

#> java -jar stelin.jar -ht -8 trainingText.txt fileWithSecretMessage.txt myPassword_AEf23te1 fileWithStegoTextOut

Examples of hidden data with 3 order and satanic mode (all possible stegotexts are created):

#> java -jar stelin.jar -hs -3 trainingText.txt fileWithSecretMessage.txt myPassword_AEf23te1 fileWithStegoTextOut

Examples of hidden data with 3 order, stegotext number 100 and template:

#> java -jar stelin.jar -ht -3 trainingText.txt fileWithSecretMessage.txt myPassword_AEf23te1 fileWithStegoTextOut 100

If you use big training text it is possible you need use Xmx parameter:

#> java -jar -Xmx1500M stelin.jar -ht -9 BigtrainingText.txt fileWithSecretMessage.txt myPassword_AEf23te1 fileWithStegoTextOut

Security & Recommendations & Limitations

1. Secret message is encrypted with RIJNDAEL (KEY 256 bits - BLOCK 256 bits)

2. Alphabet supported (secret message) in Stelin beta v.0.1 is: abcdefghijklmnñopqrstuvwxyzABCDEFGHIJKLMNÑOPQRSTUVWXYZ0123456789:/;=@¿?% & |!_"'<>()*.[] space +-

3. Before encrypted each character is codified with 6 bits that depend on the user's password. PRNG (CTR mode)based on Rijndael (Key 256 bits - Block 256 bits) is used.

4. Template file help you to improve your stegotext (more human).

5. Training text bigger help you to create stegotext smaller.

More information

1. Generating Spanish stegotext for fun and profit. Rooted Con Conference. Alfonso Muñoz. Madrid 2010 [PDF]

2. Estegoanálisis aplicado a la generación automática de estegotextos en lengua española. Alfonso Muñoz, Justo Carracedo. CIBSI 2009. V Congreso Iberoamericano de Seguridad Informática. 16-18 Nov 2009. Montevideo-Uruguay.

3. Improving N-Gram linguistic steganography based on templates. International Conference on Security and Cryptography. Secrypt 2010. July 26-28 Athens, Greece. Alfonso Muñoz, Irina Argüelles, Justo Carracedo.

Information