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Password Protected Secret Sharing from Lattices

Conference Paper


Abstract


  • A password protected secret sharing (PPSS ) allows a user to store shares of a secret on a set of L servers, and use a single password to authenticate itself to any subset of k servers at a later time to access the shares and reconstruct the secret. Security of PPSS ensures that a coalition of up to k- 1 servers cannot reveal any information about the secret message or the password. A related primitive is threshold password authenticated key exchange protocol (TPAKE ) that allows a user to establish individual authenticated shared secret keys with members of a subset of k out of L servers, using a single password. These primitives are well motivated, with applications such as secure storage of secret keys, and secure group communication using passwords for authentication. In this paper, we give the first construction of these primitives that provide post-quantum security. We prove security of our constructions in concurrent setting, and in the standard model, reducing security to the decisional LWE problem.

Publication Date


  • 2021

Citation


  • Roy, P. S., Dutta, S., Susilo, W., & Safavi-Naini, R. (2021). Password Protected Secret Sharing from Lattices. In Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) Vol. 12726 LNCS (pp. 442-459). doi:10.1007/978-3-030-78372-3_17

Scopus Eid


  • 2-s2.0-85111354334

Start Page


  • 442

End Page


  • 459

Volume


  • 12726 LNCS

Abstract


  • A password protected secret sharing (PPSS ) allows a user to store shares of a secret on a set of L servers, and use a single password to authenticate itself to any subset of k servers at a later time to access the shares and reconstruct the secret. Security of PPSS ensures that a coalition of up to k- 1 servers cannot reveal any information about the secret message or the password. A related primitive is threshold password authenticated key exchange protocol (TPAKE ) that allows a user to establish individual authenticated shared secret keys with members of a subset of k out of L servers, using a single password. These primitives are well motivated, with applications such as secure storage of secret keys, and secure group communication using passwords for authentication. In this paper, we give the first construction of these primitives that provide post-quantum security. We prove security of our constructions in concurrent setting, and in the standard model, reducing security to the decisional LWE problem.

Publication Date


  • 2021

Citation


  • Roy, P. S., Dutta, S., Susilo, W., & Safavi-Naini, R. (2021). Password Protected Secret Sharing from Lattices. In Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) Vol. 12726 LNCS (pp. 442-459). doi:10.1007/978-3-030-78372-3_17

Scopus Eid


  • 2-s2.0-85111354334

Start Page


  • 442

End Page


  • 459

Volume


  • 12726 LNCS