Decomposition instead of self-composition for proving the absence of timing channels

Timos Antonopoulos, Paul Gazzillo, Michael Hicks, Eric Koskinen, Tachio Terauchi, Shiyi Wei

Research output: Contribution to journalArticlepeer-review

20 Scopus citations

Abstract

We present a novel approach to proving the absence of timing channels. The idea is to partition the program's execution traces in such a way that each partition component is checked for timing attack resilience by a time complexity analysis and that per-component resilience implies the resilience of the whole program. We construct a partition by splitting the program traces at secret-independent branches. This ensures that any pair of traces with the same public input has a component containing both traces. Crucially, the per-component checks can be normal safety properties expressed in terms of a single execution. Our approach is thus in contrast to prior approaches, such as self-composition, that aim to reason about multiple (k≥ 2) executions at once. We formalize the above as an approach called quotient partitioning, generalized to any k-safety property, and prove it to be sound. A key feature of our approach is a demand-driven partitioning strategy that uses a regex-like notion called trails to identify sets of execution traces, particularly those influenced by tainted (or secret) data. We have applied our technique in a prototype implementation tool called Blazer, based on WALA, PPL, and the brics automaton library. We have proved timing-channel freedom of (or synthesized an attack specification for) 24 programs written in Java bytecode, including 6 classic examples from the literature and 6 examples extracted from the DARPA STAC challenge problems.

Original languageEnglish
Pages (from-to)362-375
Number of pages14
JournalACM SIGPLAN Notices
Volume52
Issue number6
DOIs
StatePublished - 14 Jun 2017

Keywords

  • Blazer
  • Decomposition
  • Subtrails
  • Timing Attacks
  • Verification

Fingerprint

Dive into the research topics of 'Decomposition instead of self-composition for proving the absence of timing channels'. Together they form a unique fingerprint.

Cite this