Client-Controlled Cryptography-as-a-Service in the Cloud

Abstract

Abstract. Today, a serious concern about cloud computing is the protection of clients' data and computations against various attacks from outsiders as well as against the cloud provider. Moreover, cloud clients are rather limited in implementing, deploying and controlling their own security solutions in the cloud. The provider theoretically has access to stored keys in dormant images and deploying keys during run-time is infeasible because authenticating running VM instances is not possible. In this paper, we present a security architecture that allows for establishing secure client-controlled Cryptography-as-a-Service (CaaS) in the cloud: Our CaaS enables clients to be in control of the provisioning and usage of their credentials and cryptographic primitives. They can securely provision keys or even implement their private virtual security module (e.g., vHSM or SmartCard). All clients' cryptographic operations run in a protected client-specific secure execution domain. This is achieved by modifying the Xen hypervisor and leveraging standard Trusted Computing technology. Moreover, our solution is legacy-compatible by installing a transparent cryptographic layer for the storage and network I/O of a VM. We reduced the privileged hypercalls necessary for administration by 79%. We evaluated the effectiveness and efficiency of our design which resulted in an acceptable performance overhead.

A comprehensive meta-analysis of cryptographic security mechanisms for cloud computing

“…These services can be accessible over a cloud management interface layer, which provides access over Representational State Transfer (REST)/Simple Object Access Protocol (SOAP) Application Programming Interfaces (APIs) or a management console website (Andrey Petukhov 2008;Doroodchi et al 2009;Gruschka and Iacono 2009;Antunes and Vieira 2011;Mainka et al 2012;Falkenberg et al 2013;Blome et al 2013;Zhou and Evans 2014;Prabadevi and Jeyanthi 2014;Kupser et al 2015;Subashini and Kavitha 2011;Masood and Java 2015;Fett et al 2015). Therefore, in addition to the existing security issues for traditional setting such as access control, secure communication, data confidentiality, integrity, availability, and privacy cloud systems bring new cloud specific security challenges (Ardagna et al 2015).…”

From Security to Assurance in the Cloud

“…Bugiel et al [2011], Fernandes et al [2013], Grobauer et al [2011], Gruschka and Jensen [2010], Jensen et al [2009], Paquette et al [2010], Saripalli and Walters [2010], and Somorovsky et al [2011] Integrity Booth et al [2013], Bugiel et al [2011], Fernandes et al [2013], Grobauer et al [2011], Gruschka and Jensen [2010], Bleikertz et al [2013], Booth et al [2013], Dahbur et al [2011], Fernandes et al [2013], Gruschka and Jensen [2010], Paquette et al [2010], and Rocha and Correia [2011] …”

“…Rocha and Correia [2011] present an overview of threats to cloud confidentiality brought by malicious insiders (which can include the cloud provider), discuss possible protection mechanisms, and describe their limitations. Bleikertz et al [2013] focus on the problem of protecting a customer from attacks brought by cloud providers, also considering the scenario including malicious outsiders (tenant-on-tenant attack surface). In particular, they consider the problem of securing cryptographic operations because, in principle, providers can access stored keys and consumers are not allowed to deploy their keys at runtime only.…”

S-FaaS

“…TPMs were proposed to be used in cloud environments. Bleikertz et al [22] describe Cryptography-as-a-Service where TPM functionality is provided by the cloud. Memoir [8] presents a rollback protection framework for TPMs.…”