Abstract. Remote attestation is the activity of making a claim about properties of a target by supplying evidence to an appraiser over a network. We identify five central principles to guide development of attestation systems. We argue that (i) attestation must be able to deliver temporally fresh evidence; (ii) comprehensive information about the target should be accessible; (iii) the target, or its owner, should be able to constrain disclosure of information about the target; (iv) attestation claims should have explicit semantics to allow decisions to be derived from several claims; and (v) the underlying attestation mechanism must be trustworthy. We illustrate how to acquire evidence from a running system, and how to transport it via protocols to remote appraisers. We propose an architecture for attestation guided by these principles. Virtualized platforms, which are increasingly well supported on stock hardware, provide a natural basis for our attestation architecture.

In this paper, we present a systematic way to determine the information flow security goals achieved by systems running a secure O/S, specifically systems running Security-Enhanced Linux. A formalization of the access control mechanism of the SELinux security server, together with a labeled transition system representing an SELinux configuration, provides our framework. Information flow security goal statements expressed in linear temporal logic provide a clear description of the objectives that SELinux is intended to achieve. We use model checking to determine whether security goals hold in a given system. These formal models combined with appropriate algorithms have led to automated tools for the verification of security properties in an SELinux system. Our approach has been used in other security management contexts over the past decade, under the name rigorous automated security management.

Abstract. We show how to combine trust management theories with nonce-based cryptographic protocols. The strand space framework for protocol analysis is extended by associating formulas from a trust management logic with the transmit and receive actions of the protocol principals. The formula on a transmission is a guarantee; the sender must ensure that this formula is true before sending the message. The formula on a receive event is an assumption that the recipient may rely on in deducing future guarantee formulas. The strand space framework allows us to prove that a protocol is sound, in the sense that when a principal relies on a formula, another principal has previously guaranteed it. We explain the ideas in reference to a simple new electronic commerce protocol, in which a customer obtains a money order from a bank to pay a merchant to ship some goods.

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Abstract. Cryptographic protocols are useful for trust engineering in distributed transactions. Transactions require specific degrees of confidentiality and agreement between the principals engaging in it. Moreover, trust management assertions may be attached to protocol actions, constraining the behavior of a principal to be compatible with its own trust policy. We embody these ideas in a cryptographic protocol programming language cppl at the Dolev-Yao level of abstraction. A strand space semantics for cppl shaped our compiler development, and allows a protocol designer to prove that a protocol is sound.