Bibliography

Steganographic File Systems

The steganographic file system is a method of storing files in such a way that encrypts data and hides it so that it cannot be proven to be there. A steganographic file system can:

• Hide users' documents in other seemingly random files.

• Allow the owner to give names and passwords for some files while keeping others secret.

• Behave like a second layer of secrecy. Encrypted files are out in the open and visible but not understandable. Stego files are not even visible and an outsider cannot look for files that "are not there."

A stego file system can protect from some threats:

• Torture to reveal crypto keys or other secrets.

• When conducting delicate negotiations, such as between a company and a trade union, informal offers may be made, which will be denied in the event of later litigation; however, the other side might obtain court orders for access to documents.

The steganographic file system, along with being practical, offers the following functionality:

• Users can plausibly deny certain files being stored on the disk.

• Guaranteed confidentiality of hidden files.

• The deletion of hidden and nonhidden files ensures secure destruction.

• Layers of security can be used, ensuring that the compromise of lower layers does not reveal the presence of higher ones.

• Deniability of the existence of higher layers.

• The installation of the driver can be justified by the additional security advantages it provides.

• Write accesses that are performed while not all hidden layers are open are unlikely to damage data in hidden files.

• Write access to hidden files between inspections cannot be distinguished from nonhidden files that have been created or deleted.

• Nonhidden files are accessible when the StegFS driver and its block allocation table are temporarily removed.

• UNIX file system semantics are implemented.