by Luis Merino, Jean-Philippe Aumasson,

Summary : Software Guard Extensions (SGX) is a technology available in Intel(R) CPUs released in autumn 2015. SGX allows a remote server to process a client's secret data within a software enclave that hides the secrets from the operating system, hypervisor, and even BIOS or chipset manager, while giving cryptographic evidence to the client that the code has been executed correctly the very definition of secure remote computation.
This talk is the first public assessment of SGX based on real SGX-enabled hardware and on Intel's software development environment. While researchers already scrutinized Intel's partial public documentation, many properties can only be verified and documented by working with the real thing: What's really in the development environment? Which components are implemented in microcode and which are in software? How can developers create secure enclaves that won't leak secrets? Can the development environment be trusted? How to debug and analyze SGX software? What crypto schemes are used in SGX critical components? How reliable are they? How safe are their implementations? Based on these newly documented aspects, we'll assess the attack surface and real risk for SGX users. We'll then present and demo proofs-of-concept of cryptographic functionalities leveraging SGX: secure remote storage and delegation (what fully homomorphic encryption promises, but is too slow to put in practice), and reencryption. We'll see how basic architectures can deliver powerful crypto functionalities with a wide range of applications. We'll release code as well as a tool to extract and verify an enclave's metadata.