Libshrincs: A C implementation with a machine-checked security proof

Ensuring a seamless transition between different cryptographic security models, particularly at the SHRINCS composition boundary, requires meticulous attention to several critical implementation details. Among these, one of the foremost priorities is to guarantee that the digest is finalized prior to any exposure of the WOTS public key, as premature revelation could undermine the intended security guarantees.

Furthermore, mechanisms must be put in place to prevent state rollback, an issue that could otherwise lead to the unintended reuse of keys. Key reuse poses significant risks, including potential vulnerabilities to forgery and compromise of cryptographic integrity. Addressing this concern necessitates robust state management strategies that can reliably detect and prevent rollbacks.

Developing a comprehensive composition argument that explicitly encompasses these requirements would significantly streamline the process of verifying compliance with SHRINCS standards. Such clarity would not only facilitate assessment but also strengthen confidence in the alignment of the construction with established security practices.