[Resource Topic] 2003/015: A Universally Composable Cryptographic Library

Welcome to the resource topic for 2003/015

Title:
A Universally Composable Cryptographic Library

Authors: Michael Backes, Birgit Pfitzmann, Michael Waidner

Abstract:

Bridging the gap between formal methods and cryptography has recently received a lot of interest, i.e., investigating to what extent proofs of cryptographic protocols made with abstracted cryptographic operations are valid for real implementations. However, a major goal has not been achieved yet: a soundness proof for an abstract crypto-library as needed for the cryptographic protocols typically proved with formal methods, e.g., authentication and key exchange protocols. Prior work that directly justifies the typical Dolev-Yao abstraction is restricted to passive adversaries and certain protocol environments. Prior work starting from the cryptographic side entirely hides the cryptographic objects, so that the operations are not composable: While secure channels or signing of application data is modeled, one cannot encrypt a signature or sign a key.

We make the major step towards this goal: We specify an abstract crypto-library that allows composed operations, define a cryptographic realization, and prove that the abstraction is sound for arbitrary active attacks in arbitrary reactive scenarios. The library currently contains public-key encryption and signatures, nonces, lists, and application data.

The proof is a novel combination of a probabilistic, imperfect bisimulation with cryptographic reductions and static information-flow analysis.

ePrint: https://eprint.iacr.org/2003/015

See all topics related to this paper.

Feel free to post resources that are related to this paper below.

Example resources include: implementations, explanation materials, talks, slides, links to previous discussions on other websites.

For more information, see the rules for Resource Topics .