Using purpose-built functions and block hashes to enable small block and sub-file forensics

  • Authors:
  • Simson Garfinkel;Alex Nelson;Douglas White;Vassil Roussev

  • Affiliations:
  • Naval Postgraduate School, Graduate School of Operational and Informational Science, Department of Computer Science, Monterey CA 93943, USA;Naval Postgraduate School, Graduate School of Operational and Informational Science, Department of Computer Science, Monterey CA 93943, USA;Naval Postgraduate School, Graduate School of Operational and Informational Science, Department of Computer Science, Monterey CA 93943, USA;Department of Computer Science, University of New Orleans, New Orleans, LA 70148, USA

  • Venue:
  • Digital Investigation: The International Journal of Digital Forensics & Incident Response
  • Year:
  • 2010

Quantified Score

Hi-index 0.00

Visualization

Abstract

This paper explores the use of purpose-built functions and cryptographic hashes of small data blocks for identifying data in sectors, file fragments, and entire files. It introduces and defines the concept of a ''distinct'' disk sector-a sector that is unlikely to exist elsewhere except as a copy of the original. Techniques are presented for improved detection of JPEG, MPEG and compressed data; for rapidly classifying the forensic contents of a drive using random sampling; and for carving data based on sector hashes.