Information-Flow Security for a Core of JavaScript

Abstract

Abstract-Tracking information flow in dynamic languages remains an important and intricate problem. This paper makes substantial headway toward understanding the main challenges and resolving them. We identify language constructs that constitute a core of JavaScript: objects, higher-order functions, exceptions, and dynamic code evaluation. The core is powerful enough to naturally encode native constructs as arrays, as well as functionalities of JavaScript's API from the document object model (DOM) related to document tree manipulation and event processing. As the main contribution, we develop a dynamic type system that guarantees information-flow security for this language.

A Functional View of Imperative Information Flow

“…This research has aimed to develop, then to use, flexible and efficient systems that satisfy non-interference properties. For instance, this research effectively supports promising uses of dynamic information-flow control in Web browsers [5,8,12,21]. This research is often clever and intricate-so we do not attempt to give a complete description here, but we focus on some of the intricacies below.…”

Secure multi-execution of web scripts: Theory and practice

“…One then tries to enforce that information only flows upward through the program. This is often formalised as non-interference -a deterministic program is non-interferent if there are no two runs of the program with inputs identical up to a level l but some different outputs at a level below l. While there has been a substantial body of research on information flow security over the past decades, the JavaScript language, and the web context bring significant additional challenges, including e.g., dealing with the dynamic nature of JavaScript [33,27].…”

“…Sabelfeld et al have proposed monitoring algorithms that can handle DOM-like structures [50], dynamic code evaluation [5] and timeouts [49]. In a recent paper, Hedin and Sabelfeld [27] propose dynamic mechanisms for all the core JavaScript language features. Austin and Flanagan [7] have developed alternative, sometimes more permissive techniques.…”

Micro-Policies: Formally Verified, Tag-Based Security Monitors

“…There, the PUMP was used only to implement dynamic IFC; other special-purpose hardware mechanisms enforced properties such as memory safety [55] and compartmentalization [40]. Still, the PUMP design in the SAFE system was made quite flexible, since dynamic IFC is an active area of research, with various mechanisms [14], [18], [19], [48], [50], [78] and "label models" [61], [77] being proposed regularly, making baked-into-hardware solutions unattractive. A simple IFC micro-policy was studied formally for an idealized version of the SAFE processor [15].…”