skip to main content

Attention:

The NSF Public Access Repository (NSF-PAR) system and access will be unavailable from 11:00 PM ET on Thursday, October 10 until 2:00 AM ET on Friday, October 11 due to maintenance. We apologize for the inconvenience.


Title: Compositional Information Flow Monitoring for Reactive Programs
To prevent applications from leaking users' private data to attackers, researchers have developed runtime information flow control (IFC) mechanisms. Most existing approaches are either based on taint tracking or multi-execution, and the same technique is used to protect the entire application. However, today's applications are typically composed of multiple components from heterogenous and unequally trusted sources. The goal of this paper is to develop a framework to enable the flexible composition of IFC enforcement mechanisms. More concretely, we focus on reactive programs, which is an abstract model for event-driven programs including web and mobile applications. We formalize the semantics of existing IFC enforcement mechanisms with well-defined interfaces for composition, define knowledge-based security guarantees that can precisely quantify the effect of implicit leaks from taint tracking, and prove sound all composed systems that we instantiate the framework with. We identify requirements for future enforcement mechanisms to be securely composed in our framework. Finally, we implement a prototype in OCaml and compare the effects of different compositions.  more » « less
Award ID(s):
1704542
NSF-PAR ID:
10385222
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
2022 IEEE 7th European Symposium on Security and Privacy (EuroS&P)
Page Range / eLocation ID:
467 to 486
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
More Like this
  1. Dynamic taint tracking, a technique that traces relationships between values as a program executes, has been used to support a variety of software engineering tasks. Some taint tracking systems only consider data flows and ignore control flows. As a result, relationships between some values are not reflected by the analysis. Many applications of taint tracking either benefit from or rely on these relationships being traced, but past works have found that tracking control flows resulted in over-tainting, dramatically reducing the precision of the taint tracking system. In this article, we introduce Conflux , alternative semantics for propagating taint tags along control flows. Conflux aims to reduce over-tainting by decreasing the scope of control flows and providing a heuristic for reducing loop-related over-tainting. We created a Java implementation of Conflux and performed a case study exploring the effect of Conflux on a concrete application of taint tracking, automated debugging. In addition to this case study, we evaluated Conflux ’s accuracy using a novel benchmark consisting of popular, real-world programs. We compared Conflux against existing taint propagation policies, including a state-of-the-art approach for reducing control-flow-related over-tainting, finding that Conflux had the highest F1 score on 43 out of the 48 total tests. 
    more » « less
  2. Hardware enclaves are designed to execute small pieces of sensitive code or to operate on sensitive data, in isolation from larger, less trusted systems. Partitioning a large, legacy application requires significant effort. Partitioning an application written in a managed language, such as Java, is more challenging because of mutable language characteristics, extensive code reachability in class libraries, and the inevitability of using a heavyweight runtime. Civet is a framework for partitioning Java applications into enclaves. Civet reduces the number of lines of code in the enclave and uses language-level defenses, including deep type checks and dynamic taint-tracking, to harden the enclave interface. Civet also contributes a partitioned Java runtime design, including a garbage collection design optimized for the peculiarities of enclaves. Civet is efficient for data-intensive workloads; partitioning a Hadoop mapper reduces the enclave overhead from 10 to 16–22% without taint-tracking or 70–80% with taint-tracking. 
    more » « less
  3. Dynamic taint tracking is an information flow analysis that can be applied to many areas of testing. Phosphor is the first portable, accurate and performant dynamic taint tracking system for Java. While previous systems for performing general-purpose taint tracking in the JVM required specialized research JVMs, Phosphor works with standard off-the-shelf JVMs (such as Oracle's HotSpot and OpenJDK's IcedTea). Phosphor also differs from previous portable JVM taint tracking systems that were not general purpose (e.g. tracked only tags on Strings and no other type), in that it tracks tags on all variables. We have also made several enhancements to Phosphor, to track taint tags through control flow (in addition to data flow), as well as to track an arbitrary number of relationships between taint tags (rather than be limited to only 32 tags). In this demonstration, we show how developers writing testing tools can benefit from Phosphor, and explain briefly how to interact with it. 
    more » « less
  4. Securing blockchain smart contracts is difficult, especially when they interact with one another. Existing tools for reasoning about smart contract security are limited in one of two ways: they either cannot analyze cooperative interaction between contracts, or they require all interacting code to be written in a specific language. We propose an approach based on information flow control~(IFC), which supports fine-grained, compositional security policies and rules out dangerous vulnerabilities. However, existing IFC systems provide few guarantees on interaction with legacy contracts and unknown code. We extend existing IFC constructs to support these important functionalities while retaining compositional security guarantees, including reentrancy control. We mix static and dynamic mechanisms to achieve these goals in a flexible manner while minimizing run-time costs. 
    more » « less
  5. Eye-tracking is an essential tool in many fields, yet existing solutions are often limited for customized applications due to cost or lack of flexibility. We present OpenIris, an adaptable and user-friendly open-source framework for video-based eye-tracking. OpenIris is developed in C# with modular design that allows further extension and customization through plugins for different hardware systems, tracking, and calibration pipelines. It can be remotely controlled via a network interface from other devices or programs. Eye movements can be recorded online from camera stream or offline post-processing recorded videos. Example plugins have been developed to track eye motion in 3-D, including torsion. Currently implemented binocular pupil tracking pipelines can achieve frame rates of more than 500Hz. With the OpenIris framework, we aim to fill a gap in the research tools available for high-precision and high-speed eye-tracking, especially in environments that require custom solutions that are not currently well-served by commercial eye-trackers. 
    more » « less