Abstract
We give a tighter security proof for authenticated key exchange (AKE) protocols that are generically constructed from key encapsulation mechanisms (KEMs) in the quantum random oracle model (QROM). Previous works (Hövelmanns et al., PKC 2020) gave reductions for such a KEM-based AKE protocol in the QROM to the underlying primitives with square-root loss and a security loss in the number of users and total sessions. Our proof is much tighter and does not have square-root loss. Namely, it only loses a factor depending on the number of users, not on the number of sessions.
Our main enabler is a new variant of lossy encryption which we call parameter lossy encryption. In this variant, there are not only lossy public keys but also lossy system parameters. This allows us to embed a computational assumption into the system parameters, and the lossy public keys are statistically close to the normal public keys. Combining with the Fujisaki-Okamoto transformation, we obtain the first tightly IND-CCA secure KEM in the QROM in a multi-user (without corruption), multi-challenge setting.
Finally, we show that a multi-user, multi-challenge KEM implies a square-root-tight and session-tight AKE protocol in the QROM. By implementing the parameter lossy encryption tightly from lattices, we obtain the first square-root-tight and session-tight AKE from lattices in the QROM.
Supported by the Research Council of Norway under Project No. 324235.
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Notes
- 1.
For all security bounds in this section, we ignore all additive and negligible statistical terms.
- 2.
This is a relaxed tightness notion from [8] where security loss is at most linear in the security parameter \(\lambda \).
References
Alwen, J., Krenn, S., Pietrzak, K., Wichs, D.: Learning with rounding, revisited - new reduction, properties and applications. In: Canetti, R., Garay, J.A. (eds.) CRYPTO 2013, Part I. LNCS, vol. 8042, pp. 57–74. Springer, Heidelberg (2013). https://doi.org/10.1007/978-3-642-40041-4_4
Ambainis, A., Hamburg, M., Unruh, D.: Quantum security proofs using semi-classical oracles. In: Boldyreva, A., Micciancio, D. (eds.) CRYPTO 2019, Part II. LNCS, vol. 11693, pp. 269–295. Springer, Cham (2019). https://doi.org/10.1007/978-3-030-26951-7_10
Bellare, M., Hofheinz, D., Yilek, S.: Possibility and impossibility results for encryption and commitment secure under selective opening. In: Joux, A. (ed.) EUROCRYPT 2009. LNCS, vol. 5479, pp. 1–35. Springer, Heidelberg (2009). https://doi.org/10.1007/978-3-642-01001-9_1
Bellare, M., Rogaway, P.: Random oracles are practical: a paradigm for designing efficient protocols. In: Denning, D.E., Pyle, R., Ganesan, R., Sandhu, R.S., Ashby, V. (eds.) ACM CCS 1993, pp. 62–73. ACM Press (1993)
Bellare, M., Rogaway, P.: Entity authentication and key distribution. In: Stinson, D.R. (ed.) CRYPTO 1993. LNCS, vol. 773, pp. 232–249. Springer, Heidelberg (1994). https://doi.org/10.1007/3-540-48329-2_21
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). https://doi.org/10.1007/11761679_25
Boneh, D., Dagdelen, Ö., Fischlin, M., Lehmann, A., Schaffner, C., Zhandry, M.: Random oracles in a quantum world. In: Lee, D.H., Wang, X. (eds.) ASIACRYPT 2011. LNCS, vol. 7073, pp. 41–69. Springer, Heidelberg (2011). https://doi.org/10.1007/978-3-642-25385-0_3
Chen, J., Wee, H.: Fully, (almost) tightly secure IBE and dual system groups. In: Canetti, R., Garay, J.A. (eds.) CRYPTO 2013, Part II. LNCS, vol. 8043, pp. 435–460. Springer, Heidelberg (2013). https://doi.org/10.1007/978-3-642-40084-1_25
Fujioka, A., Suzuki, K., Xagawa, K., Yoneyama, K.: Strongly secure authenticated key exchange from factoring, codes, and lattices. In: Fischlin, M., Buchmann, J., Manulis, M. (eds.) PKC 2012. LNCS, vol. 7293, pp. 467–484. Springer, Heidelberg (2012). https://doi.org/10.1007/978-3-642-30057-8_28
Fujioka, A., Suzuki, K., Xagawa, K., Yoneyama, K.: Practical and post-quantum authenticated key exchange from one-way secure key encapsulation mechanism. In: Chen, K., Xie, Q., Qiu, W., Li, N., Tzeng, W.G. (eds.) ASIACCS 2013, pp. 83–94. ACM Press (2013)
Fujisaki, E., Okamoto, T.: Secure integration of asymmetric and symmetric encryption schemes. J. Cryptol. 26(1), 80–101 (2013)
Gentry, C., Peikert, C., Vaikuntanathan, V.: Trapdoors for hard lattices and new cryptographic constructions. Cryptology ePrint Archive, Report 2007/432 (2007). https://eprint.iacr.org/2007/432
Gentry, C., Peikert, C., Vaikuntanathan, V.: Trapdoors for hard lattices and new cryptographic constructions. In: Ladner, R.E., Dwork, C. (eds.) 40th ACM STOC, pp. 197–206. ACM Press (2008)
Gjøsteen, K., Jager, T.: Practical and tightly-secure digital signatures and authenticated key exchange. In: Shacham, H., Boldyreva, A. (eds.) CRYPTO 2018, Part II. LNCS, vol. 10992, pp. 95–125. Springer, Cham (2018). https://doi.org/10.1007/978-3-319-96881-0_4
Han, S., et al.: Authenticated key exchange and signatures with tight security in the standard model. In: Malkin, T., Peikert, C. (eds.) CRYPTO 2021, Part IV. LNCS, vol. 12828, pp. 670–700. Springer, Cham (2021). https://doi.org/10.1007/978-3-030-84259-8_23
Hemenway, B., Libert, B., Ostrovsky, R., Vergnaud, D.: Lossy encryption: constructions from general assumptions and efficient selective opening chosen ciphertext security. In: Lee, D.H., Wang, X. (eds.) ASIACRYPT 2011. LNCS, vol. 7073, pp. 70–88. Springer, Heidelberg (2011). https://doi.org/10.1007/978-3-642-25385-0_4
Hofheinz, D., Hövelmanns, K., Kiltz, E.: A modular analysis of the Fujisaki-Okamoto transformation. In: Kalai, Y., Reyzin, L. (eds.) TCC 2017, Part I. LNCS, vol. 10677, pp. 341–371. Springer, Cham (2017). https://doi.org/10.1007/978-3-319-70500-2_12
Hofheinz, D., Jager, T., Rupp, A.: Public-key encryption with simulation-based selective-opening security and compact ciphertexts. In: Hirt, M., Smith, A. (eds.) TCC 2016, Part II. LNCS, vol. 9986, pp. 146–168. Springer, Heidelberg (2016). https://doi.org/10.1007/978-3-662-53644-5_6
Hövelmanns, K., Kiltz, E., Schäge, S., Unruh, D.: Generic authenticated key exchange in the quantum random oracle model. In: Kiayias, A., Kohlweiss, M., Wallden, P., Zikas, V. (eds.) PKC 2020, Part II. LNCS, vol. 12111, pp. 389–422. Springer, Cham (2020). https://doi.org/10.1007/978-3-030-45388-6_14
Jager, T., Kiltz, E., Riepel, D., Schäge, S.: Tightly-secure authenticated key exchange, revisited. In: Canteaut, A., Standaert, F.-X. (eds.) EUROCRYPT 2021, Part I. LNCS, vol. 12696, pp. 117–146. Springer, Cham (2021). https://doi.org/10.1007/978-3-030-77870-5_5
Jiang, H., Zhang, Z., Chen, L., Wang, H., Ma, Z.: IND-CCA-secure key encapsulation mechanism in the quantum random oracle model, revisited. In: Shacham, H., Boldyreva, A. (eds.) CRYPTO 2018, Part III. LNCS, vol. 10993, pp. 96–125. Springer, Cham (2018). https://doi.org/10.1007/978-3-319-96878-0_4
Jiang, H., Zhang, Z., Ma, Z.: Key encapsulation mechanism with explicit rejection in the quantum random oracle model. In: Lin, D., Sako, K. (eds.) PKC 2019, Part II. LNCS, vol. 11443, pp. 618–645. Springer, Cham (2019). https://doi.org/10.1007/978-3-030-17259-6_21
Katsumata, S., Yamada, S., Yamakawa, T.: Tighter security proofs for GPV-IBE in the quantum random oracle model. In: Peyrin, T., Galbraith, S. (eds.) ASIACRYPT 2018, Part II. LNCS, vol. 11273, pp. 253–282. Springer, Cham (2018). https://doi.org/10.1007/978-3-030-03329-3_9
Kiltz, E., Lyubashevsky, V., Schaffner, C.: A concrete treatment of Fiat-Shamir signatures in the quantum random-oracle model. In: Nielsen, J.B., Rijmen, V. (eds.) EUROCRYPT 2018, Part III. LNCS, vol. 10822, pp. 552–586. Springer, Cham (2018). https://doi.org/10.1007/978-3-319-78372-7_18
Krawczyk, H.: SIGMA: the “SIGn-and-MAc’’ approach to authenticated Diffie-Hellman and its use in the IKE protocols. In: Boneh, D. (ed.) CRYPTO 2003. LNCS, vol. 2729, pp. 400–425. Springer, Heidelberg (2003). https://doi.org/10.1007/978-3-540-45146-4_24
Krawczyk, H.: HMQV: a high-performance secure Diffie-Hellman protocol. In: Shoup, V. (ed.) CRYPTO 2005. LNCS, vol. 3621, pp. 546–566. Springer, Heidelberg (2005). https://doi.org/10.1007/11535218_33
Libert, B., Sakzad, A., Stehlé, D., Steinfeld, R.: All-but-many lossy trapdoor functions and selective opening chosen-ciphertext security from LWE. In: Katz, J., Shacham, H. (eds.) CRYPTO 2017, Part III. LNCS, vol. 10403, pp. 332–364. Springer, Cham (2017). https://doi.org/10.1007/978-3-319-63697-9_12
Liu, X., Wang, M.: QCCA-secure generic key encapsulation mechanism with tighter security in the quantum random oracle model. In: Garay, J.A. (ed.) PKC 2021, Part I. LNCS, vol. 12710, pp. 3–26. Springer, Cham (2021). https://doi.org/10.1007/978-3-030-75245-3_1
Micciancio, D., Regev, O.: Worst-case to average-case reductions based on Gaussian measures. In: 45th FOCS, pp. 372–381. IEEE Computer Society Press (2004)
Pan, J., Wagner, B., Zeng, R.: Lattice-based authenticated key exchange with tight security. In: Handschuh, H., Lysyanskaya, A. (eds.) CRYPTO 2023. LNCS, pp. 616–647. Springer, Cham (2023). https://doi.org/10.1007/978-3-031-38554-4_20
Pan, J., Wagner, B., Zeng, R.: Tighter security for generic authenticated key exchange in the QROM. Cryptology ePrint Archive (2023). https://ia.cr/2023/1380
Pan, J., Zeng, R.: Compact and tightly selective-opening secure public-key encryption schemes. In: Agrawal, S., Lin, D. (eds.) ASIACRYPT 2022, Part III. LNCS, vol. 13793, pp. 363–393. Springer, Heidelberg (Dec (2022). https://doi.org/10.1007/978-3-031-22969-5_13
Regev, O.: On lattices, learning with errors, random linear codes, and cryptography. In: Gabow, H.N., Fagin, R. (eds.) 37th ACM STOC, pp. 84–93. ACM Press (2005)
Saito, T., Xagawa, K., Yamakawa, T.: Tightly-secure key-encapsulation mechanism in the quantum random oracle model. In: Nielsen, J.B., Rijmen, V. (eds.) EUROCRYPT 2018, Part III. LNCS, vol. 10822, pp. 520–551. Springer, Cham (2018). https://doi.org/10.1007/978-3-319-78372-7_17
Unruh, D.: Post-quantum verification of Fujisaki-Okamoto. In: Moriai, S., Wang, H. (eds.) ASIACRYPT 2020, Part I. LNCS, vol. 12491, pp. 321–352. Springer, Cham (2020). https://doi.org/10.1007/978-3-030-64837-4_11
Xue, H., Au, M.H., Yang, R., Liang, B., Jiang, H.: Compact authenticated key exchange in the quantum random oracle model. Cryptology ePrint Archive, Report 2020/1282 (2020). https://eprint.iacr.org/2020/1282
Zhandry, M.: Secure identity-based encryption in the quantum random oracle model. In: Safavi-Naini, R., Canetti, R. (eds.) CRYPTO 2012. LNCS, vol. 7417, pp. 758–775. Springer, Heidelberg (2012). https://doi.org/10.1007/978-3-642-32009-5_44
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Pan, J., Wagner, B., Zeng, R. (2023). Tighter Security for Generic Authenticated Key Exchange in the QROM. In: Guo, J., Steinfeld, R. (eds) Advances in Cryptology – ASIACRYPT 2023. ASIACRYPT 2023. Lecture Notes in Computer Science, vol 14441. Springer, Singapore. https://doi.org/10.1007/978-981-99-8730-6_13
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