Quantum computing is a serious threat to our current cryptographic standards. Hash-Based Signatures (HBS) are a quantum-safe option for firmware or code-signing applications. However, they have limitations in regards to safely managing HBS state in disaster recovery and survivability scenarios. In this whitepaper, we examine how the concept of sectorization is appropriate for mitigating HBS’ shortcomings using the LMS-HBS method defined in RFC 8554, though everything discussed is also realizable using XMSS (RFC 8391).
Sectorization
Sectorization is a means to partition the 2n signatures generated by an HBS into 2s cryptographically-isolated segments, each with its own independent states that all tie into a single public key at the root of the HBS scheme. This whitepaper will elaborate on how these sectors, in the face of permanent or temporary outages, allow organizations to confidently generate a new multi-sector HBS scheme in a suitable hardware device and then export the resulting sector private keys using suitable levels of protection and oversight. These keys can then be distributed as per the functional and procedural requirements of the application to ensure the appropriate levels of performance and survivability.
Jim Goodman – Co-founder & Principal Security Architect
Jim has 25+ years of experience developing software, firmware and hardware for security-related products including his contribution in the design and development of next-generation game console security features. He played a key role in the definition of the Displayport interface and its security features and was one of the security architects for Chrysalis-ITS’ security processor. He has also developed several functions that have received patents. Jim holds a Ph.D. and Master’s degree from the Massachusetts Institute of Technology (MIT), where his research focused on cryptographic algorithm design and implementation. In addition, he holds a Bachelor of Applied Science, Electrical Engineering, from the University of Waterloo.
