SteelCore: an extensible concurrent separation logic for effectful dependently typed programs

Abstract

Much recent research has been devoted to modeling effects within type theory. Building on this work, we observe that effectful type theories can provide a foundation on which to build semantics for more complex programming constructs and program logics, extending the reasoning principles that apply within the host effectful type theory itself. Concretely, our main contribution is a semantics for concurrent separation logic (CSL) within the F ★ proof assistant in a manner that enables dependently typed, effectful F ★ programs to make use of concurrency and to be specified and verified using a full-featured, extensible CSL. In contrast to prior approaches, we directly derive the partial-correctness Hoare rules for CSL from the denotation of computations in the effectful semantics of non-deterministically interleaved atomic actions. Demonstrating the flexibility of our semantics, we build generic, verified libraries that support various concurrency constructs, ranging from dynamically allocated, storable spin locks, to protocol-indexed channels. We conclude that our effectful semantics provides a simple yet expressive basis on which to layer domainspecific languages and logics for verified, concurrent programming.

Zooid: a DSL for certified multiparty computation: from mechanised metatheory to certified multiparty processes

“…As a recent example, Hinrichsen et al [23] explore the notion of semantic typing using a concurrent separation logic as a semantic domain to build on top a language to describe binary session types. On the same vein, SteelCore [43] allows DSLs to take advantage of solid the semantic foundations provided by a proof assistant. Where their works use separation logic as a foundation, Zooid uses MPST and their coinductive expansion.…”

An incremental path towards a safer OS kernel

“…Concurrent Verified Components. With few exceptions [15,16,27,33,40,52,57], few systems verification methodologies reason about shared-memory concurrency. There are simple ways to safely layer concurrent reasoning on top of a singlethreaded verification.…”

On algebraic abstractions for concurrent separation logics

“…Later, Cao et al [2017] unified different semantics of separation logics using ordered separation algebras to account for affine aspects of various memory models; that is, to model whether deallocation is explicitly allowed to the user, or is carried out implicitly by garbage collection. Several program logics continue this trend, adding further properties to PCMs to give semantics to (higherorder) ghost state [da Rocha Pinto et al 2014;Dinsdale-Young et al 2013Gotsman et al 2007;Hobor et al 2010;Jung et al 2018Jung et al , 2015Krishnaswami et al 2012;Svendsen and Birkedal 2014;Svendsen et al 2013;Swamy et al 2020;Turon et al 2014]. In this paper we don't consider higherorder state and focus on the algebraic treatment of PCMs without additional properties, as these aren't required by our ambient logic, which admits explicit deallocation.…”

“…Recently, several program logics, most notably those that are built on top of the Iris framework [Bizjak et al 2019;Hinrichsen et al 2020;Jung et al 2018Jung et al , 2020Jung et al , 2015, the SteelCore framework [Swamy et al 2020], VST [Appel et al 2014], and also FCSL [Ley-Wild and Nanevski 2013;Nanevski et al 2014;Sergey et al 2015aSergey et al ,b, 2016, have allowed PCMs to be declared at the user level, and sometimes even constructed by means of a predetermined set of combinators.…”