Corten - Foundational Verification of Rust Programs

Abstract

We present Corten, a foundational verification framework for Rust programs in the Rocq theorem prover, built on the Iris separation logic framework. Corten provides the first semantics of surface-level Rust mechanized in a proof assistant with an attached program logic, directly grounded in the Rust Reference: it deeply embeds the Typed High-level Intermediate Representation (THIR) into Rocq and formalises Rust's dynamic semantics as a weakest-precondition predicate transformer calculus. By operating at THIR rather than on internal compiler representations, Corten proof goals display the THIR AST, which pretty-prints to surface Rust, keeping verification close to the source code and facilitating maintainability as code evolves. Atop this semantics, Corten develops a program logic and a syntax-directed proof automation layer; the program logic includes defunctionalized continuation stacks that keep proof goals first-order and compact. Soundness is established incrementally, construct by construct, against an interaction-trees denotation. A synthetic test suite demonstrates a two-to-four times reduction in proof size compared to raw semantic proofs. We further showcase Corten on a buddy allocator case study, verifying memory safety of the allocation and deallocation functions, laying the groundwork for end-to-end verification in a shared Rocq semantic foundation spanning hardware-software boundaries.