11,570 research outputs found
The development of a program analysis environment for Ada
A unit level, Ada software module testing system, called Query Utility Environment for Software Testing of Ada (QUEST/Ada), is described. The project calls for the design and development of a prototype system. QUEST/Ada design began with a definition of the overall system structure and a description of component dependencies. The project team was divided into three groups to resolve the preliminary designs of the parser/scanner: the test data generator, and the test coverage analyzer. The Phase 1 report is a working document from which the system documentation will evolve. It provides history, a guide to report sections, a literature review, the definition of the system structure and high level interfaces, descriptions of the prototype scope, the three major components, and the plan for the remainder of the project. The appendices include specifications, statistics, two papers derived from the current research, a preliminary users' manual, and the proposal and work plan for Phase 2
A Survey of Symbolic Execution Techniques
Many security and software testing applications require checking whether
certain properties of a program hold for any possible usage scenario. For
instance, a tool for identifying software vulnerabilities may need to rule out
the existence of any backdoor to bypass a program's authentication. One
approach would be to test the program using different, possibly random inputs.
As the backdoor may only be hit for very specific program workloads, automated
exploration of the space of possible inputs is of the essence. Symbolic
execution provides an elegant solution to the problem, by systematically
exploring many possible execution paths at the same time without necessarily
requiring concrete inputs. Rather than taking on fully specified input values,
the technique abstractly represents them as symbols, resorting to constraint
solvers to construct actual instances that would cause property violations.
Symbolic execution has been incubated in dozens of tools developed over the
last four decades, leading to major practical breakthroughs in a number of
prominent software reliability applications. The goal of this survey is to
provide an overview of the main ideas, challenges, and solutions developed in
the area, distilling them for a broad audience.
The present survey has been accepted for publication at ACM Computing
Surveys. If you are considering citing this survey, we would appreciate if you
could use the following BibTeX entry: http://goo.gl/Hf5FvcComment: This is the authors pre-print copy. If you are considering citing
this survey, we would appreciate if you could use the following BibTeX entry:
http://goo.gl/Hf5Fv
Badger: Complexity Analysis with Fuzzing and Symbolic Execution
Hybrid testing approaches that involve fuzz testing and symbolic execution
have shown promising results in achieving high code coverage, uncovering subtle
errors and vulnerabilities in a variety of software applications. In this paper
we describe Badger - a new hybrid approach for complexity analysis, with the
goal of discovering vulnerabilities which occur when the worst-case time or
space complexity of an application is significantly higher than the average
case. Badger uses fuzz testing to generate a diverse set of inputs that aim to
increase not only coverage but also a resource-related cost associated with
each path. Since fuzzing may fail to execute deep program paths due to its
limited knowledge about the conditions that influence these paths, we
complement the analysis with a symbolic execution, which is also customized to
search for paths that increase the resource-related cost. Symbolic execution is
particularly good at generating inputs that satisfy various program conditions
but by itself suffers from path explosion. Therefore, Badger uses fuzzing and
symbolic execution in tandem, to leverage their benefits and overcome their
weaknesses. We implemented our approach for the analysis of Java programs,
based on Kelinci and Symbolic PathFinder. We evaluated Badger on Java
applications, showing that our approach is significantly faster in generating
worst-case executions compared to fuzzing or symbolic execution on their own
Automated unit-level testing with heuristic rules
Software testing plays a significant role in the development of complex software systems. Current testing methods generally require significant effort to generate meaningful test cases. The QUEST/Ada system is a prototype system designed using CLIPS to experiment with expert system based test case generation. The prototype is designed to test for condition coverage, and attempts to generate test cases to cover all feasible branches contained in an Ada program. This paper reports on heuristics sued by the system. These heuristics vary according to the amount of knowledge obtained by preprocessing and execution of the boolean conditions in the program
Evolutionary improvement of programs
Most applications of genetic programming (GP) involve the creation of an entirely new function, program or expression to solve a specific problem. In this paper, we propose a new approach that applies GP to improve existing software by optimizing its non-functional properties such as execution time, memory usage, or power consumption. In general, satisfying non-functional requirements is a difficult task and often achieved in part by optimizing compilers. However, modern compilers are in general not always able to produce semantically equivalent alternatives that optimize non-functional properties, even if such alternatives are known to exist: this is usually due to the limited local nature of such optimizations. In this paper, we discuss how best to combine and extend the existing evolutionary methods of GP, multiobjective optimization, and coevolution in order to improve existing software. Given as input the implementation of a function, we attempt to evolve a semantically equivalent version, in this case optimized to reduce execution time subject to a given probability distribution of inputs. We demonstrate that our framework is able to produce non-obvious optimizations that compilers are not yet able to generate on eight example functions. We employ a coevolved population of test cases to encourage the preservation of the function's semantics. We exploit the original program both through seeding of the population in order to focus the search, and as an oracle for testing purposes. As well as discussing the issues that arise when attempting to improve software, we employ rigorous experimental method to provide interesting and practical insights to suggest how to address these issues
Talos: Neutralizing Vulnerabilities with Security Workarounds for Rapid Response
Considerable delays often exist between the discovery of a vulnerability and
the issue of a patch. One way to mitigate this window of vulnerability is to
use a configuration workaround, which prevents the vulnerable code from being
executed at the cost of some lost functionality -- but only if one is
available. Since program configurations are not specifically designed to
mitigate software vulnerabilities, we find that they only cover 25.2% of
vulnerabilities.
To minimize patch delay vulnerabilities and address the limitations of
configuration workarounds, we propose Security Workarounds for Rapid Response
(SWRRs), which are designed to neutralize security vulnerabilities in a timely,
secure, and unobtrusive manner. Similar to configuration workarounds, SWRRs
neutralize vulnerabilities by preventing vulnerable code from being executed at
the cost of some lost functionality. However, the key difference is that SWRRs
use existing error-handling code within programs, which enables them to be
mechanically inserted with minimal knowledge of the program and minimal
developer effort. This allows SWRRs to achieve high coverage while still being
fast and easy to deploy.
We have designed and implemented Talos, a system that mechanically
instruments SWRRs into a given program, and evaluate it on five popular Linux
server programs. We run exploits against 11 real-world software vulnerabilities
and show that SWRRs neutralize the vulnerabilities in all cases. Quantitative
measurements on 320 SWRRs indicate that SWRRs instrumented by Talos can
neutralize 75.1% of all potential vulnerabilities and incur a loss of
functionality similar to configuration workarounds in 71.3% of those cases. Our
overall conclusion is that automatically generated SWRRs can safely mitigate
2.1x more vulnerabilities, while only incurring a loss of functionality
comparable to that of traditional configuration workarounds.Comment: Published in Proceedings of the 37th IEEE Symposium on Security and
Privacy (Oakland 2016
.NET/C# instrumentation for search-based software testing
C# is one of the most widely used programming languages. However, to the best of our knowledge, there has been no work in the literature aimed at enabling search-based software testing techniques for applications running on the .NET platform, like the ones written in C#. In this paper, we propose a search-based approach and an open source tool to enable white-box testing for C# applications. The approach is integrated with a .NET bytecode instrumentation, in order to collect code coverage at runtime during the search. In addition, by taking advantage of Branch Distance, we define heuristics to better guide the search, e.g., how heuristically close it is to cover a branch in the source code. To empirically evaluate our technique, we integrated our tool into the EvoMaster test generation tool and conducted experiments on three .NET RESTful APIs as case studies. Results show that our technique significantly outperforms gray-box testing tools in terms of code coverage.publishedVersio
- …