Hugo A. López

Types for Secure Pattern Matching with Local Knowledge in Universal Concurrent Constraint Programming

The fundamental primitives of Concurrent Constraint Programming (CCP),

Enforcing Availability in Failure-Aware Communicating Systems

{\mathit{tell}}

A declarative framework for security: secure concurrent constraint programming

and

Time and exceptional behavior in multiparty structured interactions

{\mathit {ask}}

A Logic for Choreographies

, respectively adds knowledge to and infers knowledge from a shared constraint store. These features, and the elegant use of the constraint system to represent the abilities of attackers, make concurrent constraint programming and timed CCP ( tcc ) interesting candidates for modeling and reasoning about security protocols. However, they lack primitives for the communication of secrets (or local names as in the *** -calculus) between agents. The recently proposed

Choreographing cyber-physical distributed control systems for the energy sector

{\mathit{universal}} {\mathtt{tcc}}

Declarative interpretations of session-based concurrency

( utcc ) introduces a universally quantified ask operation that makes it possible to infer knowledge which is local to other agents. However, it allows agents to guess knowledge even if it is encrypted or communicated on secret channels, simply by quantifying over both the encryption key (or channel) and the message simultaneously. We present a secure utcc ( utcc s ) based on: (i) a simple type system for constraints allowing to distinguish between restricted (secure) and non-restricted (universally quantifiable) variables in constraints, and (ii) a generalization of the universally quantified ask operation to allow the assumption of local knowledge. We illustrate the use of the utcc s calculus with examples on communication of local names (as in the *** -calculus) and for giving semantics to secure pattern matching in a prototypical security language.

Models for Trustworthy Service and Process Oriented Systems

Choreographic programming is a programming-language design approach that drives error-safe protocol development in distributed systems. Motivated by challenging scenarios in Cyber-Physical Systems CPS, we study how choreographic programming can cater for dynamic infrastructures where the availability of components may change at runtime. We introduce the Global Quality Calculus

Proceedings Second International Workshop on Programming Language Approaches to Concurrency and Communication-cEntric Software, PLACES 2009, York, UK, 22nd March 2009.

GC_q