In theory by definition, it is better with path sensitive analysis than flow sensitive analysis. We propose a constraintbased flowsensitive static analysis for concurrent programs by iteratively composing threadmodular abstract interpreters via the use of a system of lightweight constraints. As such, solutions for alpha1 and alpha2 can differ. Flowsensitive pointer analysis computes for each program point what memory locations pointer expressions may refer to flowinsensitive pointer analysis computes what memory locations pointer. Static analysis is more efficient than analyses performed dynamically such as tracing of an execution. Two common integer anomalies are integer overflow and integer underflow.
Static analysis for extracting permission checks of a large scale framework. Svf is a static tool that enables scalable and precise interprocedural. We address the aforementioned challenges by performing sparse analysis along the defuse chains precomputed by a pre analysis and a series of thread interference analysis phases, as illustrated in figure2. We give an algorithm for precise flowinsensitive analysis of programs with finite memory, based on a novel technique for. Flowsensitive, contextsensitive, and objectsensitive. The exposed vulnerabilities seriously endanger the interests of service providers and customers.
Our static taint analysis algorithm is built upon the iterative dataflow framework kildall1973 and has been implemented in the tool saint simple static static taint analysis tool. Suppress the dataflowsensitive static analysis hazards in asm js. This question was asked earlier but the answers are very generic. The static analysis is apparently not smart enough to see that failname returns false all the way up to the compiler root, so. Our static code analyzer is built on top of those analysis methods and combines symbolic execution and formal verification. It provides unique code analysis to detect bugs and focuses on detecting undefined behaviour and dangerous coding constructs.
Semisparse flowsensitive pointer analysis ucsb computer. Dataflow analysis is a technique for gathering information about the possible set of values calculated at various points in a computer program. Precise static analyses are context, field and flow sensitive. A frequently used method for optimizing a flowsensitive dataflow analysis is to perform a sparse analysis. This paper presents androlic, a precise static analysis framework for android which is flow, context, object, field and pathsensitive. In this chapter, we explain why this can be useful and interesting, and we discuss the basic.
Deepscan is an advanced static analysis tool engineered to support javascript, typescript, react, and vue. We describe a combination of runtime information and static analysis for checking properties of complex and. The program summary graph and flowsensitive interprocedural data flow analysis david callahan department of computer science p. Dataflow analysis is typically pathinsensitive, though it is possible to define data flow. The main drawback to the dynamic analysis is the decrease in the execution speed. Runtime instrumentation for precise flowsensitive type analysis 301 to include in the application code base, making a conservative analysis entirely useless. This is a list of tools for static code analysis language multilanguage. The stanford suif compiler group programming tools. Suppress the dataflowsensitive static analysis hazards.
A static analysis model for php vulnerabilities based. It has been also shown that sound purely dynamic information flow enforcement is more permissive than static analysis in the flow insensitive case. Static analysis computes data flows conservatively flowsensitive intraprocedural analysis flowinsensitive interprocedural analysis uses andersens pointsto algorithm scales to very large programs same assumptions as analysis for optimization pointer arithmetic cannot navigate between. Therefore the user has to provide annotations describing which parts of the program. Video created by university of maryland, college park for the course software security. Crosssite scripting prevention with dynamic data tainting. This tool is an extension of compiler technology or sometime compiler also came along with this analysis feature. Existing analysis tools focus on specific problems and vary in supported sensitivity, which make them difficult to reuse and extend for new analysis tasks. Traditionally, static analyses are often used to gather information on the modification, preservation and usage of data quantities for the purpose of code optimization 7. Integer anamolies take place when arithmetic operations on integer values yield new values that cannot be. Implementing a language with flowsensitive and structural. Runtime instrumentation for precise flowsensitive type analysis 3 the complex behavior of the php interpreter. This paper describes a static analysis algorithm to detect potential integer anomalies in software.
We propose a constraintbased flow sensitive static analysis for concurrent programs by iteratively composing threadmodular abstract interpreters via the use of a system of light. Static program analysis aims to automatically answer questions about the possible behaviors of programs. The challenges and solutions for analyzing android. Dataflow analysis is a technique for gathering information about the possible set of values. Pointer analysis is a fundamental static analysis, on which many other. Based on our experience as php programmers, we believe that this is a reasonable design decision. Structural subtyping, where subtyping between data types is implict and. With the widespread usage of web applications, the security issues of source code are increasing. Acm transactions on software engineering and methodology tosem 2008. Solving both cfl problems along the same data flow path is undecidable, which is why most flow sensitive data flow analyses overapproximate fieldsensitivity through k. It is explicitly designed to find errors in large, complex multithreaded systems. Svf pointer analysis and program depedence analysis in llvm view wiki on github download source code download dockerfile what is svf. Several other analyzers use path sensitive analysis based on abstract interpretation, that is also great however that has both advantages and disadvantages. In fact i have not found a decent definition of context yet.
Static analysis computes data flows conservatively flowsensitive intraprocedural analysis flowinsensitive interprocedural analysis uses andersens pointsto algorithm scales to very large. It has been previously shown that flow sensitive static information flow analysis is a natural generalization of flow insensitive static analysis, which allows accepting more secure programs. Static flowsensitive security analysis alejandro russo andrei sabelfeld dept. You can use deepscan to find possible runtime errors and quality issues instead of coding conventions.
Svf is a static tool that enables scalable and precise. Runtime instrumentation for precise flow sensitive type analysis 3 the complex behavior of the php interpreter. The program summary graph and flow sensitive interprocedural data flow analysis david callahan department of computer science p. Sparse flowsensitive pointer analysis for multithreaded programs. The program summary graph and flowsensitive interprocedural.
It has been previously shown that flowsensitive static informationflow analysis is a natural generalization of flowinsensitive static analysis, which allows accepting more secure programs. Static analysis techniques used from an analysis of over forty research papers published between 20092014 by usenix, acm, ieee and more. We propose a constraintbased flowsensitive static analysis for concurrent programs by iteratively composing threadmodular abstract interpreters via the use of a system of light. This is achieved with an extremely flexible type system which utilises the following features.
Flowsensitive composition of threadmodular abstract. I guess that might be easier than adding dataflow to the analysis, but honestly, id rather make the analysis smarter than add yet more runtime assertions for static properties. We introduce a new regionbased selective flowsensitive selfs approach to interprocedural pointer analysis for c that operates on the regions partitioned from a program. Saint simple static taint analysis tool internet archive. Flowsensitive pointer analysis for millions of lines of code. Contribute to svftoolssvf development by creating an account on github. In programming language theory, flow sensitive typing or flow typing is a type system where the type of an expression depends on its position in the control flow in statically typed languages, a type of an expression is determined by the types of the subexpressions that compose it. A programs control flow graph cfg is used to determine those. Our indepth examination has led to several key findings.
By choosing the flow lattice to be the powerset of program variables, we obtain a system. Data flow analysis is a technique for gathering information about the possible set of values calculated at various points in a computer program. Incremental analysis code change incremental phase program unit change. Our implementation can treat all software product lines developed in the javabased color ide cide 5. In programming language theory, flowsensitive typing or flow typing is a type system where the type of an expression depends on its position in the control flow in statically typed languages, a type of an. Sparse flowsensitive pointer analysis for multithreaded. Joana java objectsensitive analysis information flow. The static analysis tool is software which works in a nonrun time environment. A programs control flow graph cfg is used to determine those parts of a program to which a particular value assigned to a variable might propagate. Apache yetus a collection of build and release tools. Our static taint analysis is interprocedural, flow sensitive, and developers can choose to run it either with contextsensitivity or without. Integrate with your github repositories to get quality insight into your web project. So here is our example again, but reworked to be in ssa form.
The analysis identified 200 problems in the code and in the type hints of the original source code base. For example this paper makes extensive use of context in this context. Keywords pointer analysis, sparse analysis, flowsensitivity. Precise static analyses are context, field and flowsensitive. A frequently used method for optimizing a flowsensitive dataflow analysis is to perform a sparse analysis, such as in the flowsensitive pointsto analysis of 2, 12. And this is converting the program to what is called static single assignment form or ssa. Box 1892 rice university houston, texas 77251 1 introduction this paper discusses a method for interprocedural data flow analysis which is powerful enough to express flow. Context, flow and fieldsensitive dataflow analysis. Based on our experience as php programmers, we believe that this is a reasonable design. This means that automated reasoning of software generally must. Apr 15, 2020 firstly, it converts source code to an intermediate representation and then performs flow sensitive analysis, interprocedural analysis, context sensitive analysis and object sensitive analysis.
Information flow control ifc checks whether a program can leak secret data to public ports, or whether critical computations can be influenced from outside. But perhaps its not worth the trouble, especially since you might have to sprinkle a lot of these around. Program analysis for software tools and engineering paste, pp. Our method is compositional in that it first applies sequential abstract interpreters to individual threads and then composes their results. In sas 2004 11th static analysis symposium, verona, italy, august 2004, volume 3148 of lncs, pages 100115. Integer anamolies take place when arithmetic operations on integer values yield new values that cannot be represented in the range for the integer type. Traditionally, static analyses are often used to gather information on the modification, preservation. Sparse flowsensitive pointer analysis for multithreaded programs yulei sui, peng di, and jingling xue unsw australia. Symposium on software testing and analysis, pages 3144, 2006. An incremental pointsto analysis with cflreachability. On flowsensitive security types conference record of the 33rd.
Racerx is a static tool that uses flow sensitive, interprocedural analysis to detect both race conditions and deadlocks. Included is the precommit module that is used to execute full and partialpatch ci builds that provides static analysis of code via other open source tools as part of a configurable report. In this chapter, we explain why this can be useful and interesting, and we discuss the basic characteristics of analysis tools. Citeseerx document details isaac councill, lee giles, pradeep teregowda. I am interested to know what context means in the context of static code analysis, specifically with java and when used in conjunction with the term context in sensitive analysis. Moreover, dynamic analysis can gain more precise information flow of a program than a static analysis would 6. Flowsensitive type qualifiers department of computer science. Full text of saint simple static taint analysis tool. The result is typically used by dead code elimination to remove statements that assign to a variable. In most cases the analysis is performed on some version of the source code, and in the other cases, some form of the object code the term is usually applied to the analysis. Phantm analyzes each function separately by default but uses php documentation features to allow users to declare types of function. From the softwareprotection point of view, static analysis.
The main drawback to the dynamic analysis is the decrease in the execution speed because the monitor must be run with every execution, while static analysis is run once for all prior to the execution. Our flowsensitive algorithm is based on a sparse representation of program code. Parallel flowsensitive pointsto analysis jisheng zhao rice university jisheng. Developer mostly uses the static analysis tools just to test software component and development process. Regionbased selective flowsensitive pointer analysis. Context, flow and fieldsensitive dataflow analysis using. Context, flow, and fieldsensitive dataflow analysis using.
Joana is a framework that allows to statically analyze a given java program for integrity and confidentiality. Suppress the dataflowsensitive static analysis hazards in. For flow sensitive analysis, in particular dataflow analysis chapter 5. It has been previously shown that flow sensitive static information flow analysis is a natural generalization of flowinsensitive static analysis, which allows accepting more secure programs. Flowsensitive pointer analysis computes for each program point what memory locations pointer expressions may refer to flowinsensitive pointer analysis computes what memory locations pointer expressions may refer to, at any time in program execution flowsensitive pointer analysis is traditionally too expensive to perform for whole. Flowsensitive types, which are adopted from flowsensitive program analysis e.
Context and fieldsensitivity are both expressible as contextfree language cfl reachability problems. Firstly, it converts source code to an intermediate representation and then performs flow sensitive analysis, interprocedural analysis, context sensitive analysis and object sensitive analysis. Flowinsensitive static analysis for detecting integer. We introduce a new regionbased selective flow sensitive selfs approach to interprocedural pointer analysis for c that operates on the regions partitioned from a program. Dataflow analysis is typically pathinsensitive, though it is possible to define dataflow. Runtime instrumentation for precise flowsensitive type. Svf allows valueflow construction and pointer analysis to be performed iteratively, thereby. We have applied our analysis tool to over 50000 lines of php code, including the popular dokuwiki software, which has a plugin architecture. Some of these problems can cause exploits, infinite loops, and crashes. I am interested to know what context means in the context of static code analysis, specifically with java and when used in conjunction with. To summarize, this paper presents the following original contributions.
We propose a constraintbased flow sensitive static analysis for concurrent programs by iteratively composing threadmodular abstract interpreters via the use of a system of lightweight constraints. The traditional flowsensitive approach 4, 14, 27 uses a dense iterative dataflow analysis, which does not scale to large programs. Flow sensitivity is maintained between the regions but not inside, making traditional flow insensitive and flow sensitive as well as recent sparse flow sensitive analyses. Context, flow, and fieldsensitive dataflow analysis. Static program analysis is the analysis of computer software that is performed without actually executing programs, in contrast with dynamic analysis, which is analysis performed on programs while they are executing. Runtime instrumentation for precise flowsensitive type analysis. Our static taint analysis algorithm is built upon the iterative dataflow framework 11111171 and has been implemented in the tool saint simple static taint analysis tool. The algorithm uses a fully flowsensitive and contextsensitive analysis to derive the likely object invariants and to check that the objects are used consistently throughout the program. Box 1892 rice university houston, texas 77251 1 introduction. We could even implement such a flow sensitive analysis by transforming the program to assign to a variable at most once. Static analysis techniques used for android security analysis. Because of the variety of concerns in static analysis of android apps, it is important for the field, which has already produced substantial. In this paper, we present fsam, a new flow sensitive pointer analysis for handling large multithreaded c programs using pthreads.
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