Affiliations: [a] Dipartimento di Matematica e Informatica, Università degli Studi di Cagliari, Italy | [b] Dipartimento di Informatica, Università di Pisa, Pisa, Italy
Correspondence:
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Corresponding author: Massimo Bartoletti, Dipartimento di Matematica e Informatica, Università degli Studi di Cagliari, Via Ospedale, 72, I-09124 Cagliari, Italy. Tel.: +39 070 675 8540; Fax: +39 070 675 8504; E-mail: bart@unica.it.
Abstract: A static approach is proposed to study secure composition of services. We extend the λ-calculus with primitives for selecting and invoking services that respect given security requirements. Security-critical code is enclosed in policy framings with a possibly nested, local scope. Policy framings enforce safety and liveness properties. The actual run-time behaviour of services is over-approximated by a type and effect system. Types are standard, and effects include the actions with possible security concerns – as well as information about which services may be invoked at run-time. An approximation is model checked to verify policy framings within their scopes. This allows for removing any run-time execution monitor, and for determining the plans driving the selection of those services that match the security requirements on demand.
Keywords: Service-oriented computing, language-based security, usage policies, call-by-contract, type and effect systems, model-checking
