Advertisement

Confidential and Auditable Payments

  • Tatsuo MitaniEmail author
  • Akira Otsuka
Conference paper
  • 155 Downloads
Part of the Lecture Notes in Computer Science book series (LNCS, volume 12063)

Abstract

In this paper, we construct the Confidential and Auditable Payments (CAP) scheme. We keep the transaction confidential by writing ciphertexts of transactions in a ledger. We realize the soundness of the CAP scheme by the soundness of the zero-knowledge proof. A court or an authority controls a unique secret key of the ciphertexts written in the ledger. They can enforce confidential transactions open with the secret key according to the legal procedure. There are many works for protecting the transaction’s privacy strictly. However, these works do not have a forcibly auditable function, to the best of our knowledge. The proposed scheme is both confidential and auditable. It eliminates concerns about money laundering caused by excessively confidential transactions and contributes to the sound use of blockchain.

Keywords

Blockchain Homomorphic encryption Zero-knowledge proof 

Supplementary material

References

  1. 1.
    Benhamouda, F., Camenisch, J., Krenn, S., Lyubashevsky, V., Neven, G.: Better zero-knowledge proofs for lattice encryption and their application to group signatures. In: Sarkar, P., Iwata, T. (eds.) ASIACRYPT 2014. LNCS, vol. 8873, pp. 551–572. Springer, Heidelberg (2014).  https://doi.org/10.1007/978-3-662-45611-8_29CrossRefGoogle Scholar
  2. 2.
    Boyle, E., Kohl, L., Scholl, P.: Homomorphic secret sharing from lattices without FHE. In: Ishai, Y., Rijmen, V. (eds.) EUROCRYPT 2019. LNCS, vol. 11477, pp. 3–33. Springer, Cham (2019).  https://doi.org/10.1007/978-3-030-17656-3_1CrossRefGoogle Scholar
  3. 3.
    Brakerski, Z., Vaikuntanathan, V.: Fully homomorphic encryption from ring-LWE and security for key dependent messages. In: Rogaway, P. (ed.) CRYPTO 2011. LNCS, vol. 6841, pp. 505–524. Springer, Heidelberg (2011).  https://doi.org/10.1007/978-3-642-22792-9_29CrossRefGoogle Scholar
  4. 4.
    Bünz, B., Agrawal, S., Zamani, M., Boneh, D.: Zether: towards privacy in a smart contract world. IACR Cryptology ePrint Archive 2019/191 (2019)Google Scholar
  5. 5.
    Bünz, B., Bootle, J., Boneh, D., Poelstra, A., Wuille, P., Maxwell, G.: Bulletproofs: short proofs for confidential transactions and more. In: 2018 IEEE Symposium on Security and Privacy (SP), pp. 315–334. IEEE (2018)Google Scholar
  6. 6.
    Gennaro, R., Gentry, C., Parno, B., Raykova, M.: Quadratic span programs and succinct NIZKs without PCPs. In: Johansson, T., Nguyen, P.Q. (eds.) EUROCRYPT 2013. LNCS, vol. 7881, pp. 626–645. Springer, Heidelberg (2013).  https://doi.org/10.1007/978-3-642-38348-9_37CrossRefGoogle Scholar
  7. 7.
    Gentry, C.: Fully homomorphic encryption using ideal lattices. In: Proceedings of the Forty-First Annual ACM Symposium on Theory of Computing. STOC 1909, pp. 169–178. Association for Computing Machinery, New York (2009).  https://doi.org/10.1145/1536414.1536440
  8. 8.
    Goldwasser, S., Micali, S., Rackoff, C.: The knowledge complexity of interactive proof systems. SIAM J. Comput. 18(1), 186–208 (1989)MathSciNetCrossRefGoogle Scholar
  9. 9.
    Lyubashevsky, V., Peikert, C., Regev, O.: On ideal lattices and learning with errors over rings. J. ACM (JACM) 60(6), 43 (2013)MathSciNetCrossRefGoogle Scholar
  10. 10.
    Miers, I., Garman, C., Green, M., Rubin, A.D.: Zerocoin: anonymous distributed e-cash from bitcoin. In: 2013 IEEE Symposium on Security and Privacy, pp. 397–411. IEEE (2013)Google Scholar
  11. 11.
    Mitani, T., Otsuka, A.: Traceability in permissioned blockchain. In: 2019 IEEE International Conference on Blockchain (Blockchain), pp. 286–293, July 2019.  https://doi.org/10.1109/Blockchain.2019.00045
  12. 12.
    Mitani, T., Otsuka, A.: Traceability in permissioned blockchain. IEEE. Access 8, 21573–21588 (2020).  https://doi.org/10.1109/ACCESS.2020.2969454CrossRefGoogle Scholar
  13. 13.
    Nakamoto, S., et al.: Bitcoin: A Peer-to-peer Electronic Cash System (2008)Google Scholar
  14. 14.
    Pedersen, T.P.: Non-interactive and information-theoretic secure verifiable secret sharing. In: Feigenbaum, J. (ed.) CRYPTO 1991. LNCS, vol. 576, pp. 129–140. Springer, Heidelberg (1992).  https://doi.org/10.1007/3-540-46766-1_9CrossRefGoogle Scholar
  15. 15.
    Sasson, E.B., et al.: Zerocash: decentralized anonymous payments from bitcoin. In: 2014 IEEE Symposium on Security and Privacy, pp. 459–474. IEEE (2014)Google Scholar

Copyright information

© Springer Nature Switzerland AG 2020

Authors and Affiliations

  1. 1.Institute of Information SecurityYokohamaJapan
  2. 2.Mitsubishi Chemical Systems, Inc.TokyoJapan

Personalised recommendations