Overview
Stegstream is made up of a server and client program. The server program uses steganography to hide a file inside a MP3 music file. The music file is then made available via the server program streaming it, and it can be listened to using a web browser in the same way as normal streaming. Running the client program will extract the hidden file from the music file streamed by the server. This method allows files to be transferred in an invisible way, as any observer will simply see a music streaming service.
Design Goal
To provide a practical application of steganography that is easy for non technical people to use in order to privately distribute files to a large number of people.
Installation
Download the archive file containing the client executable for the relevant operating system from the releases. Validate the PGP signature if an integrity check is advisable, and extract the executable from the archive file. Place the executable in a suitable directory; E.G /home/username/stegstream
GnuPG Signing Key: http:https://pgp.mit.edu/pks/lookup?op=get&search=0x203092F792253A6F
Getting the hidden file from the server
Open a command prompt, and cd into the directory containing the client program.
Enter the following:
./stegstream-client serverURL
An example:
./stegstream-client http:https://localhost:8080/Audio
This will download the streamed music file and extract the hidden file from it. The music file is securely deleted after extraction has taken place. The hidden file will be written to the same directory that the client program is stored in.
Getting the hidden file from a file on the local hard drive
Open a command prompt, and cd into the directory containing the client program.
Enter the following:
./stegstream-client --local FileName
An example:
./stegstream-client --local Waves.mp3
This will extract the hidden file from the file on the local hard drive. The hidden file will be written to the same directory that the client program is stored in.
Things to consider
The hidden file is left on disk after the client program has finished. It is the responsibility of the user to securely delete this file after reading if secrecy is important.
In order for the client to see the server, make sure the computer running the server is network visible from the computer running the client – use ping to check visibility.