6,493 research outputs found
Your Proof Fails? Testing Helps to Find the Reason
Applying deductive verification to formally prove that a program respects its
formal specification is a very complex and time-consuming task due in
particular to the lack of feedback in case of proof failures. Along with a
non-compliance between the code and its specification (due to an error in at
least one of them), possible reasons of a proof failure include a missing or
too weak specification for a called function or a loop, and lack of time or
simply incapacity of the prover to finish a particular proof. This work
proposes a new methodology where test generation helps to identify the reason
of a proof failure and to exhibit a counter-example clearly illustrating the
issue. We describe how to transform an annotated C program into C code suitable
for testing and illustrate the benefits of the method on comprehensive
examples. The method has been implemented in STADY, a plugin of the software
analysis platform FRAMA-C. Initial experiments show that detecting
non-compliances and contract weaknesses allows to precisely diagnose most proof
failures.Comment: 11 pages, 10 figure
Towards Symbolic Model-Based Mutation Testing: Combining Reachability and Refinement Checking
Model-based mutation testing uses altered test models to derive test cases
that are able to reveal whether a modelled fault has been implemented. This
requires conformance checking between the original and the mutated model. This
paper presents an approach for symbolic conformance checking of action systems,
which are well-suited to specify reactive systems. We also consider
nondeterminism in our models. Hence, we do not check for equivalence, but for
refinement. We encode the transition relation as well as the conformance
relation as a constraint satisfaction problem and use a constraint solver in
our reachability and refinement checking algorithms. Explicit conformance
checking techniques often face state space explosion. First experimental
evaluations show that our approach has potential to outperform explicit
conformance checkers.Comment: In Proceedings MBT 2012, arXiv:1202.582
Specification-driven model transformation testing
The final publication is available at Springer via http://dx.doi.org/10.1007/s10270-013-0369-xTesting model transformations poses several challenges, among them the automatic generation of appropriate input test models and the specification of oracle functions. Most approaches for the generation of input models ensure a certain coverage of the source meta-model or the transformation implementation code, whereas oracle functions are frequently defined using query or graph languages. However, these two tasks are usually performed independently regardless of their common purpose, and sometimes, there is a gap between the properties exhibited by the generated input models and those considered by the transformations. Recently, we proposed a formal specification language for the declarative formulation of transformation properties (by means of invariants, pre-, and postconditions) from which we generated partial oracle functions used for transformation testing. Here, we extend the usage of our specification language for the automated generation of input test models by SAT solving. The testing process becomes more intentional because the generated models ensure a certain coverage of the transformation requirements. Moreover, we use the same specification to consistently derive both the input test models and the oracle functions. A set of experiments is presented, aimed at measuring the efficacy of our technique.We thank the referees for their
useful comments. This work has been sponsored by
the Spanish Ministry of Science and Innovation with
project “Go-Lite” (TIN2011-24139), by the R&D program
of the Community of Madrid with project “e-
Madrid” (S2009/TIC-1650), and by the German Research
Foundation (DFG) within the Reinhart Koselleck
project (DR 287/23-1)
Test Case Generation Using Visual Contracts
Visual contracts provide a diagrammatic notation for pre- and postconditionsas alternative to the Object-Constraint Language (OCL) or code-levelcontract languages. Using visual contracts for testing, we benefit from their executabilityand formal background in graph transformation to provide model-basedtest oracles and coverage criteria. Based on a static analysis of their dependenciesand conflicts, in this paper we use visual contracts to generate test cases accordingto these coverage criteria.Together with previous work, this adds up to a comprehensive approach aiming toautomate the three major challenges of testing through the use of models
An automated model-based test oracle for access control systems
In the context of XACML-based access control systems, an intensive testing
activity is among the most adopted means to assure that sensible information or
resources are correctly accessed. Unfortunately, it requires a huge effort for
manual inspection of results: thus automated verdict derivation is a key aspect
for improving the cost-effectiveness of testing. To this purpose, we introduce
XACMET, a novel approach for automated model-based oracle definition. XACMET
defines a typed graph, called the XAC-Graph, that models the XACML policy
evaluation. The expected verdict of a specific request execution can thus be
automatically derived by executing the corresponding path in such graph. Our
validation of the XACMET prototype implementation confirms the effectiveness of
the proposed approach.Comment: 7 page
Machine-Readable Privacy Certificates for Services
Privacy-aware processing of personal data on the web of services requires
managing a number of issues arising both from the technical and the legal
domain. Several approaches have been proposed to matching privacy requirements
(on the clients side) and privacy guarantees (on the service provider side).
Still, the assurance of effective data protection (when possible) relies on
substantial human effort and exposes organizations to significant
(non-)compliance risks. In this paper we put forward the idea that a privacy
certification scheme producing and managing machine-readable artifacts in the
form of privacy certificates can play an important role towards the solution of
this problem. Digital privacy certificates represent the reasons why a privacy
property holds for a service and describe the privacy measures supporting it.
Also, privacy certificates can be used to automatically select services whose
certificates match the client policies (privacy requirements).
Our proposal relies on an evolution of the conceptual model developed in the
Assert4Soa project and on a certificate format specifically tailored to
represent privacy properties. To validate our approach, we present a worked-out
instance showing how privacy property Retention-based unlinkability can be
certified for a banking financial service.Comment: 20 pages, 6 figure
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