CTV+CSFS: Can we reach consensus on a first step towards covenants?

A series of experiments outlined in a GitHub repository demonstrates the feasibility of creating a structured reveal-extract relationship utilizing CSFS script mechanisms, which are sensitive to mutations and possess defined failure boundaries. This investigation delves into an innovative approach where the extraction of a scalar value (r) from a Schnorr signature (s) minus an explicit message (e) is validated against a predetermined point (R) on an elliptic curve, facilitated by the generator point G.

The experimental setup reveals that while it's possible to establish a structured construction that allows for successful explicit-message verification and maintains an adaptor-like reveal/extract relation, the separation of paths for the adaptor scalar and Schnorr signature computation underscores the distinction between this method and traditional cryptographic coupling. Particularly noteworthy is the observation from Checkpoint C, where the absence of a unique pre-commitment to R enables multiple (s, R) pairs to satisfy the constructed relation. This outcome suggests that the observed binding behavior within these scripts emanates more from their execution structure rather than inherent properties of the Schnorr signature scheme itself.

This exploration contributes significantly to the ongoing discourse about enhancing Bitcoin's scripting capabilities, particularly in terms of introducing functionalities that enhance privacy and efficiency through novel cryptographic techniques. However, the insights garnered also highlight the complexities and considerations necessary when integrating such advancements, especially in ensuring uniqueness and security within the transaction validation process. The findings prompt further investigation into how CSFS and similar script constructions could be optimized or modified to align with the cryptographic integrity and operational requirements of Bitcoin's evolving protocol landscape.