David Robert Safford

Special feature: Two-phase cryptographic key recovery system

A two-phase method of key recovery which will be referred to as Secure Key Recovery (SKR) is presented. The proposed key recovery system permits a portion of the key recovery information to be generated once and then used for multiple encrypted data communications sessions and encrypted file applications. In particular, the portion of the key recovery information that is generated just once is the only portion that requires public key encryption operations. We also describe a verification mode in which the communicating parties each produce SKR recovery information independently, without checking the others so produced information. In this mode, if at least one side is correctly configured, all required recovery information is correctly produced. In addition, the communicating parties are free to include any optional recovery fields without causing a false invalidation of what the other parties sent. Further, we present a method of verification of key recovery information within a key recovery system, based on a variation of the three-party Diffie-Hellman key agreement procedure. Without communication with a trustee, the sender is able to encrypt recovery information in such a way that both the receiver and the respective trustee can decrypt it. This reduces the number of encryptions, and inherently validates the recovery information when the receiver decrypts it. The method allows full caching of all public key operations, thus further reducing computational overhead.

Practical server privacy with secure coprocessors

What does it take to implement a server that provides access to records in a large database, in a way that ensures that this access is completely private--even to the operator of this server? In this paper, we examine the question: Using current commercially available technology, is it practical to build such a server, for real databases of realistic size, that offers reasonable performance--scaling well, parallelizing well, working with the current client infrastructure, and enabling server operators of otherwise unknown credibility to prove their service has these privacy properties? We consider this problem in the light of commercially available secure coprocessors--whose internal memory is still much, much smaller than the typical database size--and construct an algorithm that both provides asymptotically optimal performance and also promises reasonable performance in real implementations. Preliminary prototypes support this analysis, but leave many areas for further work.

I/O for Virtual Machine Monitors: Security and Performance Issues

Modern I/O architectures are quite complex, so keeping a virtual machine monitor (VMM), or hypervisor, small is difficult. Many current hypervisors move the large, complex, and sometimes proprietary device drivers out of the VMM into one or more partitions, leading to inherent problems in complexity, security, and performance.

Autonomic 802.11 wireless LAN security auditing

The authors describe their Distributed Wireless Security Auditor (DWSA), which works toward finding unauthorized wireless access points in large-scale wireless environments while providing an autonomic and unobtrusive layer of network protection.

Trustworthy geographically fenced hybrid clouds

Adoption of hybrid clouds by enterprises has been hampered by the inability of current hybrid cloud infrastructures to provide scalable and efficient mechanisms (1) to ensure the trustworthiness and integrity of the software stack executing a hybrid application workload, or (2) to enforce governmental privacy, data jurisdiction and audit regulations by ensuring that remote data and computation do not cross specified geographic boundaries. This paper presents our vision of trustworthy geographically fenced hybrid clouds (TGHC), a generic, scalable and extensible middleware system to automatically bridge the gap between applications with their integrity and geo-fencing policies, and raw hardware infrastructure. It describes TGHCs modularly, by (a) outlining the challenges in certifying the trustworthiness of cloud computing infrastructures and in geo-fencing computation, including scalability limitations of existing solutions, (b) presenting scalable mechanisms to transform bare metal servers into trusted IaaS computing pools through integrity measurement, management and monitoring that leverage open, off-the-shelf hardware technologies like Intel TPM, (c) introducing workload specification languages to specify integrity and geo-fencing policies on hybrid workloads, and (d) extending IaaS systems to ensure that workload bursting from private data centers to public clouds uses trusted computing pools and respects geographic boundaries during initial placement of virtual machines (VMs) and further migration. We also present early results from our implementation illustrating the feasibility of our proposed architecture, and outline future research challenges in engineering and effectively using TGHCs.

Scalable Attestation: A Step Toward Secure and Trusted Clouds

In this work we present Scalable Attestation, a method which combines both secure boot and trusted boot technologies, and extends them up into the host, its programs, and up into the guests operating system and workloads, to both detect and prevent integrity attacks. Anchored in hardware, this integrity appraisal and attestation protects persistent data (files) from remote attack, even if the attack is root privileged. As an added benefit of a hardware rooted attestation, we gain a simple hardware based geolocation attestation to help enforce regulatory requirements. This design is implemented in multiple cloud test beds based on the QEMU/KVM hypervisor, Open Stack, and Open Attestation, and is shown to provide significant additional integrity protection at negligible cost.

Trusted computing and open source

Trusted computing can help defend Linux and other open source operating systems and applications from attack. It can help protect desktop and mobile Linux clients from on-line and off-line integrity and confidentiality attacks. It can measure and remotely attest to the integrity of a system. It can provide authentication mechanisms which are resistant to phishing and pharming attacks. This paper describes the features of Trusted Computings Trusted Platform Module (TPM), shows how the TPM can provide these protections, and summarizes work in the open source community to implement them.

Scalable Attestation: A Step toward Secure and Trusted Clouds

Scalable attestation combines secure boot and trusted boot technologies, and extends them up into the host, its programs, and into the guests operating system and workloads, to both detect and prevent integrity attacks. Anchored in hardware, this integrity appraisal and attestation protects persistent data (files) from remote attack, even if the attack is root privileged. As an added benefit of a hardware rooted attestation, the authors gain a simple hardware-based geolocation attestation to help enforce regulatory requirements. This design is implemented in multiple cloud testbeds based on the QEMU/KVM hypervisor, OpenStack, and OpenAttestation, and is shown to provide significant additional integrity protection at negligible cost.