Department of Computer Science and Technology


CTSRD – Rethinking the hardware-software interface for security

PIs: Robert N. M. Watson (University of Cambridge), Simon W. Moore (University of Cambridge), Peter Sewell (University of Cambridge), and Peter Neumann (SRI International)

CHERI tablet photo

September 2019: UKRI has announced the Digital Security by Design Challenge, which includes £8M EPSRC and £3M ESRC calls to support new UK research around CHERI using the Arm-built Morello CHERI-ARM 64-bit demonstrator CPU, SoC, and board (supported by InnovateUK), to be available from 2021. Videos of talks from Cambridge, Arm, and Microsoft are now online.

June 2020: We have posted a new technical report, CHERI C/C++ Programming Guide, which documents the memory-safe CHERI pure-capability C and C++ programming languages, and their implications for software implementation and portability.

September 2019: Learn about the CHERI architecture! Our technical report An Introduction to CHERI is a high-level summary of our work on CHERI architecture, microarchitecture, formal modeling, and software.

Clean Slate Trustworthy Secure Research and Development (CTSRD - pronounced "custard") is a joint research project between SRI International's Computer Science Laboratory and the University of Cambridge Computer Laboratory, supported by DARPA (part of the DARPA CRASH programme) and Google. The project is revisiting the hardware-software security interface for general-purpose CPUs to fundamentally improve security; to this end, we are integrating a hybrid capability model and continuous hardware-assisted validation of security design principles with a commodity CPU ISA and open source operating systems. We are pursuing several new software/hardware features as part of this research:

There is a strong interest, throughout, in judiciously applying formal methodology and bringing formally grounded techniques to mainstream hardware and software development. This work has motivated the creation of the Bluespec extensible RISC implementation – an open-source platform for research into the hardware-software interface, with a BSD-licensed operating system and toolchain based on FreeBSD and Clang/LLVM. We are using open source, wherever possible, to transition new technologies into mainstream use.

CTSRD builds on long past experience at both institutions in security and systems research, including Multics, PSOS, the Newcastle DSS, separation kernels, the DARPA CHATS programme, PVS/SAL/YICES, LynuxWorks, the CAP computer, the MAC Framework, multi-threaded CPU design, Xen, Capsicum, and MirageOS.

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