On Symbolic Analysis of Cryptographic Protocols

The universally composable symbolic analysis (UCSA) framework layers Dolev-Yao style symbolic analysis on top of the universally composable (UC) secure framework to construct computationally sound proofs of cryptographic protocol security. The original proposal of the UCSA framework by Canetti and Herzog (2004) focused on protocols that only use public key encryption to achieve 2-party mutual authentication or key exchange. This thesis expands the framework to include protocols that use digital signatures as well. In the process of expanding the framework, we identify a flaw in the framework’s use of UC ideal functionality Fpke. We also identify issues that arise when combining Fpke with the current formulation of ideal signature functionality Fsig. Motivated by these discoveries, we redefine the Fpke and Fsig functionalities appropriately. Thesis Supervisor: Ronald L. Rivest Title: Viterbi Professor of Computer Science Thesis Supervisor: Ran Canetti Title: Visiting Scientist