CSR - - - PDOS: A New Foundation for the Evolution of Critical Systems

这个项目的目标是为现有的C程序创建一条演变成更安全、更可验证的编程语言的道路。大多数关键软件系统都是用C编写的，这是出了名的容易受到错误和安全漏洞的攻击。尽管存在更安全的新语言，但除了完全重写之外，还没有方法来处理现有的数百万行关键C软件。研究人员创造了新的技术，将遗留的C程序转换为新的更安全的C程序变体，以及用新语言分析和重构程序的基础设施。重构允许通过基本上自动化的转换在程序安全性/安全性方面取得增量进展。早期的结果表明，将带有CPP预处理器的C程序转换成可重构且更易于分析的C变体是可能的。重要的重构，例如消除缓冲区溢出安全漏洞，可以在一些程序员的指导下基本上是自动的。除了翻译和重构技术，研究人员计划创建一种可扩展的语言，以便能够探索未来的C替代语言的特性，该替代语言支持从遗留C语言的翻译，以及通过重构导致更安全的代码的复杂分析。主要交付成果包括翻译和重构工具，定义更安全的C变体，扩展基础语言的体系结构，以及一组已翻译的程序，如操作系统的驱动程序和关键部分，它们主要展示了自动翻译和重构，以及重要C程序减少漏洞的最终目标。

The goal of this project is to create an evolutionary path for existing C programs into a safer, more verifiable programming language. The majority of critical software systems are written in C, which is notoriously vulnerable to bugs and security holes. Although new languages exist that are safer, there has been no method for handling the millions of lines of existing critical C software, except for complete rewriting. The investigators create new technology to translate legacy C programs into a new safer variant of C, as well as the infrastructure to analyze and refactor programs in the new language. Refactoring allows incremental progress in program safety/security via mostly automated transformations. Early results show that it is possible to translate C programs with the CPP preprocessor into a variant of C that is refactorable and easier to analyze, that important refactorings, such as the removal of buffer overrun security holes, can be mostly automatic with some programmer guidance.In addition to translation and refactoring technology, the investigators plan to create an extensible language to enable exploration into the features of a future replacement language for C, one that enables both translation from legacy C, and sophisticated analyses that lead to safer code via refactoring.Key deliverables include the translation and refactoring tools, the definition of a safer variant of C, an architecture for extending the base language, and a set of translated programs, such as drivers and key parts of an OS, that demonstrate both mostly automatic translation and refactoring, and the end goal of reduced vulnerabilities for important C programs.