GIT-CERCS-04-31
Mudhakar Srivatsa, Ling Liu,
Countering Targeted File Attacks Using Location Keys
Serverless distributed computing has received significant attention from both
the industry and research community. One of its typical applications is wide
area network file systems like CFS [1], Farsite [2] and OceanStore [3]. A
unique feature of these file systems is that they are serverless. They
store files on a large collection of untrusted nodes that form an overlay
network. They use cryptographic techniques to secure files from malicious
nodes. However, most of these distributed file systems are vulnerable to
targeted file attacks, wherein an adversary attempts to attack a small (chosen)
set of files in the system. This paper presents location keys as a technique
for countering targeted file attacks.
Location keys can be used to not only provide traditional cryptographic
guarantees like file confidentiality and integrity, but also (i) mitigate
Denial-of-Service (DoS) and host compromise attacks, (ii) construct an
efficient file access control mechanism, and (iii) add almost zero performance
overhead and very minimal storage overhead to the system. We also study several
potential inference attacks on location keys and present solutions that guard
the file system from such attacks.