AnBx - Security Protocols Design and Verification

Designing distributed protocols is challenging, as it requires actions at very different levels: from the choice of network-level mechanisms to protect the exchange of sensitive data, to the definition of structured interaction patterns to convey application-specific guarantees. Current security infrastructures provide very limited support for the specification of such guarantees. As a consequence, the high-level security properties of a protocol typically must often be hard-coded explicitly, in terms of low-level cryptographic notions and devices which clutter the design and undermine its scalability and robustness. To counter these problems, we propose an extended Alice & Bob notation for protocol narrations (AnBx) to be employed for a purely declarative modelling of distributed protocols. These abstractions provide a compact specification of the high-level security guarantees they convey, and help shield the design from the details of the underlying cryptographic infrastructure. We discuss an implementation of the abstractions based on a translation from the AnBx notation to the AnB language supported by the OFMC [1,2] verification tool. We show the practical effectiveness of our approach by revisiting the iKP e-payment protocols, and showing that the security goals achieved by our declarative specification outperform those offered by the original protocols

Efficient Java Code Generation of Security Protocols Specified in AnB/AnBx

The implementation of security protocols is challenging and error-prone, as experience has proved that even widely used and heavily tested protocols like TLS and SSH need to be patched every year due to low-level implementation bugs. A model-driven development approach allows automatic generation of an application, from a simpler and abstract model that can be formally verified. In this work we present the AnBx compiler, a tool for automatic generation of Java code of security protocols specified in the popular Alice & Bob notation, suitable for agile prototyping. In contrast with the existing tools, the AnBx compiler uses a simpler specification language and computes the consistency checks that agents has to perform on reception of messages. This is an important feature for robust implementations. Moreover, the tool applies various optimization strategies to achieve efficiency both at compile time and at run time. A support library interfaces the Java Cryptographic Architecture allowing for easy customization of the application