Julia Sapiña

• Doctor of Philosophy in Computer Science
• PostDoc Position at Polytechnic University of Valencia

Narrowing and unification are very useful tools for symbolic analysis of rewrite theories, and thus for any model that can be specified in that way. A very clear example of their application is the field of formal cryptographic protocol analysis, which is why narrowing and unification are used in tools such as Maude-NPA, Tamarin and Akiss. In this...

We develop an automated specialization framework for rewrite theories that model concurrent systems. A rewrite theory \(\mathscr {R}=(\Sigma ,E\uplus B,R)\) consists of two main components: an order-sorted equational theory \(\mathscr {E}=(\Sigma ,E\uplus B)\) that defines the system states as terms of an algebraic data type and a term rewriting sy...

This work provides a general mechanism for safety enforcement in rewriting logic computations. Our technique relies on an assertion-guided model transformation that leverages the newly defined Maude strategy lan-guage for ensuring rich safety policies in non-deterministic programs. The transformed system is guaranteed to comply with user-defined in...

The dual of most general equational unifiers is that of least general equational anti-unifiers, i.e., most specific anti-instances modulo equations. This work aims to provide a general mechanism for equational anti-unification that leverages the recent advances in variant-based symbolic computation in Maude. Symbolic computation in Maude equational...

Partial evaluation (PE) is a branch of computer science that achieves code optimization via specialization. This article describes a PE methodology for optimizing rewrite theories that encode concurrent as well as nondeterministic systems by means of the Maude language. The main advantages of the proposed methodology can be summarized as follows: •...

Generalization, also called anti-unification, is the dual of unification. A generalizer of two terms t and t′\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$t^{\prime }$...

This paper introduces $\tt{{Presto}}$ , a symbolic partial evaluator for Maude’s rewriting logic theories that can improve system analysis and verification. In $\tt{{Presto}}$ , the automated optimization of a conditional rewrite theory $\mathcal{R}$ (whose rules define the concurrent transitions of a system) is achieved by partially evaluating, wi...

This paper introduces Presto, a symbolic partial evaluator for Maude's rewriting logic theories that can improve system analysis and verification. In Presto, the automated optimization of a conditional rewrite theory R (whose rules define the concurrent transitions of a system) is achieved by partially evaluating, with respect to the rules of R, an...

We present a formal framework for the analysis of cryptographic protocols that make use of time and space in their execution. In a previous work we provided a timed process algebra syntax and a timed transition semantics. The timed process algebra only made message sending-and-reception times available to processes whereas the timed transition sema...

In this paper, we develop an automated optimization framework for rewrite theories that supports sorts, subsort overloading, equations and algebraic axioms with free/non-free constructors, and rewrite rules modeling concurrent system transitions whose state structure is defined by means of the equations. The main idea of the framework is to make th...

We present a framework suited to the analysis of cryptographic protocols that make use of time in their execution. We provide a process algebra syntax that makes time information available to processes, and a transition semantics that takes account of fundamental properties of time. Additional properties can be added by the user if desirable. This...

We present a framework suited to the analysis of cryptographic protocols that make use of time in their execution. We provide a process algebra syntax that makes time information available to processes, and a transition semantics that takes account of fundamental properties of time. Additional properties can be added by the user if desirable. This...

Equational unification of two terms consists of finding a substitution that, when applied to both terms, makes them equal modulo some equational properties. A narrowing-based equational unification algorithm relying on the concept of the variants of a term is available in the most recent version of Maude, version 3.0, which provides quite sophistic...

Program specialization is mainly recognized as a powerful technique for optimizing software systems. Nonetheless, it can also be productively employed in other application areas. This paper presents an assertion-guided program specialization methodology for efficiently imposing safety properties on software systems. The program specializer takes as...

Maude-NPA is an analysis tool for cryptographic security protocols that takes into account the algebraic properties of the cryptosystem. Maude-NPA can reason about a wide range of cryptographic properties. However, some algebraic properties, and protocols using them, have been beyond Maude-NPA capabilities, either because the cryptographic properti...

Program transformation is widely used for producing correct mutations of a given program so as to satisfy the user's intent that can be expressed by means of some sort of specification (e.g. logical assertions, functional specifications, reference implementations, summaries, examples). This paper describes an automated correction methodology for Ma...

Equational unification of two terms consists of finding a substitution that, when applied to both terms, makes them equal modulo some equational properties. Equational unification is of special relevance to automated deduction, theorem proving, protocol analysis, partial evaluation, model checking, etc. Several algorithms have been developed in the...

Equational unification of two terms consists of finding a substitution that, when applied to both terms, makes them equal modulo some equational properties. Equational unification is of special relevance to automated deduction, theorem proving, protocol analysis, partial evaluation, model checking, etc. Several algorithms have been developed in the...

Concurrent functional languages that are endowed with symbolic reasoning capabilities such as Maude offer a high-level, elegant, and efficient approach to programming and analyzing complex, highly nondeterministic software systems. Maude’s symbolic capabilities are based on equational unification and narrowing in rewrite theories, and provide Maude...

Concurrent functional languages that are endowed with symbolic reasoning capabilities such as Maude offer a high-level, elegant, and efficient approach to programming and analyzing complex, highly nondeterministic software systems. Maude's symbolic capabilities are based on equational unification and narrowing in rewrite theories, and provide Maude...

In this paper, we present a novel transformation method for Maude programs featuring both automatic program diagnosis and correction. The input of our method is a reference specification A of the program behavior that is given in the form of assertions together with an overly general program R whose execution might violate the assertions. Our corre...

In this paper, we present ÁTAME, an assertion-based program specialization tool for the multi-paradigm language Maude. The program specializer ÁTAME takes as input a set \(\mathcal{A}\) of system assertions that model the expected program behavior plus a Maude program \(\mathcal{R}\) to be specialized that might violate some of the assertions in \(...

This paper introduces GLINTS, a graphical tool for exploring variant narrowing computations in Maude. The most recent version of Maude, version 2.7.1, provides quite sophisticated unification features, including order-sorted equational unification for convergent theories modulo axioms such as associativity, commutativity, and identity (ACU). This n...

We present ABETS, an assertion-based, dynamic analyzer that helps diagnose errors in Maude programs. ABETS uses slicing to automatically create reduced versions of both a run's execution trace and executed program, reduced versions in which any information that is not relevant to the bug currently being diagnosed is removed. In addition, ABETS empl...

We present ABETS, an assertion-based, dynamic analyzer that helps diagnose errors in Maude programs. ABETS uses slicing to automatically create reduced versions of both a run's execution trace and executed program, reduced versions in which any information that is not relevant to the bug currently being diagnosed is removed. In addition, ABETS empl...

In this paper we propose a dynamic analysis methodology for improving the diagnosis of erroneous Maude programs. The key idea is to combine runtime checking and dynamic trace slicing for automatically catching errors at runtime while reducing the size and complexity of the erroneous traces to be analyzed (i.e., those leading to states failing to sa...

This paper introduces the idea of using assertion checking for enhancing the dynamic slicing of Maude computation traces. Since trace slicing can greatly simplify the size and complexity of the analyzed traces, our methodology can be useful for improving the diagnosis of erroneous Maude programs. The proposed methodology is based on (i) a logical n...

Trace exploration is concerned with techniques that allow computation traces to be dynamically searched for specific contents. Depending on whether the exploration is carried backward or forward, trace exploration techniques allow provenance tracking or impact tracking to be done. The aim of provenance tracking is to show how (parts of) a program o...

Trace inspection is concerned with techniques that allow the trace content to be searched for specific components. This paper presents a rich and highly dynamic, parameterized technique for the trace inspection of Rewriting Logic theories that allows the non-deterministic execution of a given unconditional rewrite theory to be followed up in differ...

We present i Julienne, a trace analyzer for conditional rewriting logic theories that can be used to compute abstract views of Maude executions that help users understand and debug programs. Given a Maude execution trace and a slicing criterion which consists of a set of target symbols occurring in a selected state of the trace, i Julienne is able...