Verifying a Compiler for Java Threads

Abstract

Abstract.A verified compiler is an integral part of every security infrastructure. Previous work has come up with formal semantics for sequential and concurrent variants of Java and has proven the correctness of compilers for the sequential part. This paper presents a rigorous formalisation (in the proof assistant Isabelle/HOL) of concurrent Java source and byte code together with an executable compiler and its correctness proof. It guarantees that the generated byte code shows exactly the same observable behaviour as the semantics for the multithreaded source code.

On the Development and Formalization of an Extensible Code Generator for Real Life Security Protocols

“…We have based our formalization of the target language on Jinja with Threads [16,17], since, to the best of our knowledge, this is the most complete and thorough formalization of Java that supports concurrency. In order to be able to use Jinja with our Coq formalization of the Extensible Spi calculus, we have manually translated the formalization of Jinja with Threads from Isabelle/HOL to Coq.…”

“…Our target language, Variant Parametric Jinja (VPJ) is based on Jinja with Threads [16,17] and the type system with variant parametric types by Igarashi et al [14]. In this section, we briefly describe VPJ with an emphasis on the modifications we have made; please refer to the original papers for more details [14][15][16][17].…”

“…In this section, we briefly describe VPJ with an emphasis on the modifications we have made; please refer to the original papers for more details [14][15][16][17]. We chose Jinja with Threads over other formalized Java fragments because of its comprehensiveness.…”

“…This has many pragmatic advantages for building a usable and secure tool: from type and memory safety, an extensive standard library and the cryptographic service provider architecture, to the ease of integrating the generated code into existing applications. However, Java is a very complex programming language, and merely adapting an existing mechanized formalization of a subset of Java [16,17] to suit our particular needs turned out to be a quite daunting task. About 7k LOC out of the 17k LOC of our formalization are solely concerned with defining our target language, VPJ.…”

Verifying an Open Compiler Using Multi-language Semantics

“…The most well known instance of this is the CompCert compiler [1,2] which uses the Coq proof assistant to both implement and verify a multi-pass optimizing compiler from C to PowerPC, ARM, and x86 assembly, proving that the compiler preserves semantics of source programs. Several other compilerverification efforts have successfully followed CompCert's lead and basic methodology, for instance, focusing on multithreaded Java [3], just-in-time compilation [4], and C with relaxed memory concurrency [5].…”