Effort-Release Public-Key Encryption from Cryptographic Puzzles

  • Jothi Rangasamy
  • Douglas Stebila
  • Colin Boyd
  • Juan Manuel González-Nieto
  • Lakshmi Kuppusamy
Part of the Lecture Notes in Computer Science book series (LNCS, volume 7372)

Abstract

Timed-release cryptography addresses the problem of “sending messages into the future”: a message is encrypted so that it can only be decrypted after a certain amount of time, either (a) with the help of a trusted third party time server, or (b) after a party performs the required number of sequential operations. We generalise the latter case to what we call effort-release public key encryption (ER-PKE), where only the party holding the private key corresponding to the public key can decrypt, and only after performing a certain amount of computation which may or may not be parallelisable. Effort-release PKE generalises both the sequential-operation-based timed-release encryption of Rivest, Shamir, and Wagner, and also the encapsulated key escrow techniques of Bellare and Goldwasser. We give a generic construction for ER-PKE based on the use of moderately hard computational problems called puzzles. Our approach extends the KEM/DEM framework for public key encryption by introducing a difficulty notion for KEMs which results in effort-release PKE. When the puzzle used in our generic construction is non-parallelisable, we recover timed-release cryptography, with the addition that only the designated receiver (in the PKE setting) can decrypt.

Keywords

puzzles difficulty timed-release encryption key escrow 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    Bellare, M., Goldwasser, S.: Encapsulated key escrow. Technical Report 688, MIT Laboratory for Computer Science (April 1996), http://cseweb.ucsd.edu/~mihir/papers/escrow.html
  2. 2.
    Bellare, M., Goldwasser, S.: Verifiable partial key escrow. In: Graveman, R., Janson, P.A., Neumann, C., Gong, L. (eds.) ACM CCS, pp. 78–91. ACM (1997)Google Scholar
  3. 3.
    Bellare, M., Rogaway, P.: The Security of Triple Encryption and a Framework for Code-Based Game-Playing Proofs. In: Vaudenay, S. (ed.) EUROCRYPT 2006. LNCS, vol. 4004, pp. 409–426. Springer, Heidelberg (2006)CrossRefGoogle Scholar
  4. 4.
    Chalkias, K., Hristu-Varsakelis, D., Stephanides, G.: Improved Anonymous Timed-Release Encryption. In: Biskup, J., López, J. (eds.) ESORICS 2007. LNCS, vol. 4734, pp. 311–326. Springer, Heidelberg (2007)CrossRefGoogle Scholar
  5. 5.
    Chen, L., Morrissey, P., Smart, N.P., Warinschi, B.: Security Notions and Generic Constructions for Client Puzzles. In: Matsui, M. (ed.) ASIACRYPT 2009. LNCS, vol. 5912, pp. 505–523. Springer, Heidelberg (2009)CrossRefGoogle Scholar
  6. 6.
    Cheon, J.H., Hopper, N., Kim, Y., Osipkov, I.: Provably secure timed-release public key encryption. ACM Trans. Inf. Syst. Secur. 11, 4:1–4:44 (2008)CrossRefGoogle Scholar
  7. 7.
    Chow, S.S.M., Yiu, S.M.: Timed-Release Encryption Revisited. In: Baek, J., Bao, F., Chen, K., Lai, X. (eds.) ProvSec 2008. LNCS, vol. 5324, pp. 38–51. Springer, Heidelberg (2008)CrossRefGoogle Scholar
  8. 8.
    Cramer, R., Shoup, V.: Design and analysis of practical public-key encryption schemes secure against adaptive chosen ciphertext attack. SIAM Journal on Computing 33(1), 167–226 (2003)MathSciNetMATHCrossRefGoogle Scholar
  9. 9.
    Dwork, C., Naor, M.: Pricing via Processing or Combatting Junk Mail. In: Brickell, E.F. (ed.) CRYPTO 1992. LNCS, vol. 740, pp. 139–147. Springer, Heidelberg (1993)Google Scholar
  10. 10.
    Juels, A., Brainard, J.: Client puzzles: A cryptographic countermeasure against connection depletion attacks. In: Proc. Network and Distributed System Security Symposium (NDSS) 1999, pp. 151–165. Internet Society (1999)Google Scholar
  11. 11.
    Okamoto, T., Pointcheval, D.: REACT: Rapid Enhanced-Security Asymmetric Cryptosystem Transform. In: Naccache, D. (ed.) CT-RSA 2001. LNCS, vol. 2020, pp. 159–175. Springer, Heidelberg (2001)CrossRefGoogle Scholar
  12. 12.
    Rangasamy, J., Stebila, D., Boyd, C., Gonzalez Nieto, J.: An integrated approach to cryptographic mitigation of denial-of-service attacks. In: Sandhu, R., Wong, D.S. (eds.) Proc. 6th ACM Symposium on Information, Computer and Communications Security (ASIACCS) 2011, pp. 114–123. ACM (2011), http://eprints.qut.edu.au/41285/
  13. 13.
    Rangasamy, J., Stebila, D., Boyd, C., Gonzalez Nieto, J., Kuppusamy, L.: Efficient modular exponentiation-based puzzles for denial-of-service protection. In: Proc. International Conference on Information Security and Cryptology (ICISC 2011). LNCS, Springer, Heidelberg (2011) (to appear), http://eprints.qut.edu.au/47894/ Google Scholar
  14. 14.
    Rivest, R.L., Shamir, A., Wagner, D.A.: Time-lock puzzles and timed-release crypto. Technical Report TR-684, MIT Laboratory for Computer Science (March 1996), http://people.csail.mit.edu/rivest/RivestShamirWagner-timelock.pdf
  15. 15.
    Shoup, V.: A proposal for an ISO standard for public key encryption (version 2.1). manuscript (2001), http://shoup.net/papers
  16. 16.
    Shoup, V.: Sequences of games: a tool for taming complexity in security proofs. Technical report (2004), http://eprint.iacr.org/2004/332
  17. 17.
    Stebila, D., Kuppusamy, L., Rangasamy, J., Boyd, C., Gonzalez Nieto, J.: Stronger Difficulty Notions for Client Puzzles and Denial-of-Service-Resistant Protocols. In: Kiayias, A. (ed.) CT-RSA 2011. LNCS, vol. 6558, pp. 284–301. Springer, Heidelberg (2011), http://eprints.qut.edu.au/40036/ CrossRefGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2012

Authors and Affiliations

  • Jothi Rangasamy
    • 1
  • Douglas Stebila
    • 1
  • Colin Boyd
    • 1
  • Juan Manuel González-Nieto
    • 1
  • Lakshmi Kuppusamy
    • 1
  1. 1.Information Security InstituteQueensland University of TechnologyBrisbaneAustralia

Personalised recommendations