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arXiv · 0803.2365

SAFIUS - A secure and accountable filesystem over untrusted storage

V Sriram·Ganesh Narayan·K Gopinath
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Abstract

We describe SAFIUS, a secure accountable file system that resides over an untrusted storage. SAFIUS provides strong security guarantees like confidentiality, integrity, prevention from rollback attacks, and accountability. SAFIUS also enables read/write sharing of data and provides the standard UNIX-like interface for applications. To achieve accountability with good performance, it uses asynchronous signatures; to reduce the space required for storing these signatures, a novel signature pruning mechanism is used. SAFIUS has been implemented on a GNU/Linux based system modifying OpenGFS. Preliminary performance studies show that SAFIUS has a tolerable overhead for providing secure storage: while it has an overhead of about 50% of OpenGFS in data intensive workloads (due to the overhead of performing encryption/decryption in software), it is comparable (or better in some cases) to OpenGFS in metadata intensive workloads.

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V Sriram, Ganesh Narayan, K Gopinath. 2008-03-16. SAFIUS - A secure and accountable filesystem over untrusted storage. https://doi.org/10.1109/sisw.2007.7

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