3 research outputs found
Security Verification of Low-Trust Architectures
Low-trust architectures work on, from the viewpoint of software,
always-encrypted data, and significantly reduce the amount of hardware trust to
a small software-free enclave component. In this paper, we perform a complete
formal verification of a specific low-trust architecture, the Sequestered
Encryption (SE) architecture, to show that the design is secure against direct
data disclosures and digital side channels for all possible programs. We first
define the security requirements of the ISA of SE low-trust architecture.
Looking upwards, this ISA serves as an abstraction of the hardware for the
software, and is used to show how any program comprising these instructions
cannot leak information, including through digital side channels. Looking
downwards this ISA is a specification for the hardware, and is used to define
the proof obligations for any RTL implementation arising from the ISA-level
security requirements. These cover both functional and digital side-channel
leakage. Next, we show how these proof obligations can be successfully
discharged using commercial formal verification tools. We demonstrate the
efficacy of our RTL security verification technique for seven different correct
and buggy implementations of the SE architecture.Comment: 19 pages with appendi
Strain Engineering in Ni-Co-Mn-Sn Magnetic Shape Memory Alloys: Influence on the Magnetic Properties and Martensitic Transformation
Ni-Mn-Sn ferromagnetic shape memory alloys, which can be stimulated by an external magnetic field, exhibit a fast response and have aroused wide attention. However, the fixed and restricted working temperature range has become a challenge in practical application. Here, we introduced strain engineering, which is an effective strategy to dynamically tune the broad working temperature region of Ni-Co-Mn-Sn alloys. The influence of biaxial strain on the working temperature range of Ni-Co-Mn-Sn alloy was systematically investigated by the ab initio calculation. These calculation results show a wide working temperature range (200 K) in Ni14Co2Mn13Sn3 FSMAs can be achieved with a slight strain from 1.5% to −1.5%, and this wide working temperature range makes Ni14Co2Mn13Sn3 meet the application requirements for both low-temperature and high-temperature (151–356 K) simultaneously. Moreover, strain engineering is demonstrated to be an effective method of tuning martensitic transformation. The strain can enhance the stability of the Ni14Co2Mn13Sn3 martensitic phase. In addition, the effects of strain on the magnetic properties and the martensitic transformation are explained by the electronic structure in Ni14Co2Mn13Sn3 FSMAs