A Generalized Two-Phase Analysis of Knowledge Flows in Security Protocols

We introduce knowledge flow analysis, a simple and flexible formalism for checking cryptographic protocols. Knowledge flows provide a uniform language for expressing the actions of principals, assumptions about intruders, and the properties of cryptographic primitives. Our approach enables a generalized two-phase analysis: we extend the two-phase theory by identifying the necessary and sufficient properties of a broad class of cryptographic primitives for which the theory holds. We also contribute a library of standard primitives and show that they satisfy our criteria. keywords: security protocols, intruder detection.