WhylSon: Proving your Michelson Smart Contracts in Why3

TL;DR

WhylSon is a verification tool that translates Michelson smart contracts into WhyML to leverage Why3's theorem proving capabilities for ensuring contract correctness.

Contribution

It introduces a novel translation from Michelson to WhyML, enabling automated formal verification of Tezos smart contracts within the Why3 framework.

Findings

Successfully translated Michelson contracts to WhyML

Automated proof of contract correctness demonstrated

Integration with Why3's theorem provers achieved

Abstract

This paper introduces WhylSon, a deductive verification tool for smart contracts written in Michelson, which is the low-level language of the Tezos blockchain. WhylSon accepts a formally specified Michelson contract and automatically translates it to an equivalent program written in WhyML, the programming and specification language of the Why3 framework. Smart contract instructions are mapped into a corresponding WhyML shallow-embedding of the their axiomatic semantics, which we also developed in the context of this work. One major advantage of this approach is that it allows an out-of-the-box integration with the Why3 framework, namely its VCGen and the backend support for several automated theorem provers. We also discuss the use of WhylSon to automatically prove the correctness of diverse annotated smart contracts.