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Paper: Deterministic Authenticated-Encryption: A Provable-Security Treatment of the Key-Wrap Problem

Authors:
Phillip Rogaway
Thomas Shrimpton
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URL: http://eprint.iacr.org/2006/221
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Abstract: Standards bodies have been addressing the key-wrap problem, a cryptographic goal that has never received a provable-security treatment. In response, we provide one, giving definitions, constructions, and proofs. We suggest that key-wrap’s goal is security in the sense of deterministic authenticated-encryption (DAE), a notion that we put forward. We also provide an alternative notion, a pseudorandom injection (PRI), which we prove to be equivalent. We provide a DAE construction, SIV, analyze its concrete security, develop a blockcipher-based instantiation of it, and suggest that the method makes a desirable alternative to the schemes of the X9.102 draft standard. The construction incorporates a method to turn a PRF that operates on a string into an equally efficient PRF that operates on a vector of strings, a problem of independent interest. Finally, we consider IV-based authenticated- encryption (AE) schemes that are maximally forgiving of repeated IVs, a goal we formalize as misuse-resistant AE.We show that a DAE scheme with a vector-valued header, such as SIV, directly realizes this goal.
BibTeX
@misc{eprint-2006-21714,
  title={Deterministic Authenticated-Encryption: A Provable-Security Treatment of the Key-Wrap Problem},
  booktitle={IACR Eprint archive},
  keywords={Authenticated encryption, cryptographic definitions, cryptographic standards, key wrapping},
  url={http://eprint.iacr.org/2006/221},
  note={An abridged version appeared at Eurocrypt 2006.  This is the full version. teshrim@cs.pdx.edu 13745 received 30 Jun 2006, last revised 20 Aug 2007},
  author={Phillip Rogaway and Thomas Shrimpton},
  year=2006
}