Concolic testing integrates concrete execution (e.g., random testing) and symbolic execution for test case generation. The differences between concolic and symbolic mode are: Concolic mode preserves concrete values for runtime values, while symbolic mode loses them. This combination of concrete (actual) and symbolic execution is referred to as concolic execution (the name concolic stems from concrete and symbolic), sometimes also called as dynamic symbolic execution. The Concolic Testing Algorithm Classify input variables into symbolic / concrete Instrument to record symbolic vars and path conditions Choose an arbitrary input Execute the program Symbolically re-execute the program Negate the unexplored last path condition Is there an input satisfying constraint F T Dynamic symbolic execution (DSE) Run / interpret the program with concrete state Symbolic state computed in parallel (concolic) Solver generates new concrete state DSE-Flavors EXE-style [Cadaret al. James C. King. I know that the term symbolic execution is the fact to use symbolic variables instead of concrete values and a concolic execution is the fact to use both. Lecture 15: Dynamic Symbolic Execution (aka Directed Automated Random Testing, aka Concolic Execution). Symbolic execution is one of the ways that we can reason about the behavior of a program without executing it. Concolic execution combines randomized concrete execution with symbolic execution and automatic constraint solving.Symbolic execution allows jCUTE to discern inputs that lead down different execution paths; randomized concrete execution helps it overcome
To solve this problem, recent studies have proposed hybrid fuzzers that observe the context of a target program using symbolic execution; these fuzzers generate test cases to bypass the sanity check. However, there are two problems with this approach. To do: Generate test cases: Black-box test generation: Fuzzing, Random testing White-box test generation: Symbolic/Concolic execution 10 VS 11. Concolic execution Also called dynamic symbolic execution Instrument the program to do symbolic execution as the program runs I.e., shadow concrete program state with symbolic variables Explore one path, from start to completion, at a time Thus, always have a concrete underlying value to rely on 21 & state merging S2E[6] Hybrid Symbolic exec. Symbolic execution and program testing. Jun Sun, Singapore University of Technology and Design
A symbolic path is associated to a set of atomic path constraints; one has to pick and negate one constraint, which may in turn result in a new path explored and new constraints to be negated. Symbolic execution is a program analysis technique introduced in the 70s that has received renewed interest in recent years, due to algorithmic advances and increased availability of computational power and constraint solving technology. During concolic testing, we identify program regions that can be encoded by BMC on-the-fly so that program paths within these regions are checked simultaneously. GKLEE is the rst concolic verier and test generator tailored for GPU programs. View 17-SymbolicExecution.pdf from COMP COMP-511 at The Hong Kong University of Science and Technology. However, the overhead of concolic execution when analyzing a single program path is still very high, limiting the scalability of the approach. Symbolic execution alone is slow and gets stuck (state explosion, loops) Combining Fuzzing and concolic execution: best of both worlds? Early work on symbolic execution Robert S. Boyer, Bernard Elspas, and Karl N. Levitt. Grace and other concolic engines tackle this more methodically. The technique begins with a concrete execution of the program on an arbitrary input, building up a symbolic representation of the path as it runs.
The Concolic Testing Algorithm Classify input variables into symbolic / concrete Instrument to record symbolic vars and path conditions Choose an arbitrary input Execute the program Symbolically re-execute the program Negate the unexplored last path condition Is there an input satisfying constraint F T Dynamic Symbolic Execution 3 Received significant interest in the last few years Many dynamic symbolic execution/concolic tools available as open-source: CREST, KLEE, SYMBOLIC JPF, etc. At each loop iteration (lines 623), the function decodes the length of the current data element with get_length (line 8). 1. The term benchmark is also commonly utilized for the purposes of elaborately designed benchmarking programs themselves. Lecture 18: Part 1: Alloy Analyzer, and Part 2: Data Model Verification for Web Applications. Program is simultaneously executed with concrete and symbolic inputs . To alleviate this, S2E also implements concolic execution. Concolic execution works exactly as traditional symbolic execution: it propagates symbolic inputs through the system, allowing conditional branches to fork new paths whenever necessary. Thanks to organizers and ISSISP Concolic and Symbolic 8 One path at a time, simplify constraints! This is achieved through an exhaustive exploration of the possible execution states. Execution would then proceed with the multiplication and the conditional branch, which would evaluate to false and print OK. During symbolic execution, the program reads a symbolic value (e.g., ) and assigns it to y. To perform a symbolic or a concolic execution we must keep the data and the control flow of each program point.
We tackled the harder problem and produced two production-quality bug-finding systems: GRR, a high-throughput fuzzer, and PySymEmu (PSE), a binary symbolic executor with support for concrete inputs. Test generation and symbolic/concrete execution. Dynamic Symbolic Execution 3 Received significant interest in the last few years Many dynamic symbolic execution/concolic tools available as open-source: CREST, KLEE, SYMBOLIC JPF, etc. CS 267 Lecture Notes. Symbolic execution allows us to execute a program through all possible execution path s, thus achieving all possible path conditions (path condition = the set of logical constraints that takes us to a specific point in the execution). Expand Symbolic execution is a program analysis technique introduced in the 70s that has received renewed interest in recent years, due to algorithmic advances and increased availability of computational power and constraint solving technology. These can then be used for further symbolic exploration with KLEE or as concrete seed for fuzzing, e.g. We present SymCC, an LLVM-based C and C++ compiler that builds concolic execution right into the binary. Concolic execution is a mix between CONCrete execution and symbOLIC execution, with the purpose of feasibility. Symbolic execution allows us to execute a program through all possible execution paths, thus achieving all possible path conditions (path condition = the set of logical constraints that takes us to a specific point in the execution). Concolic execution is a mix between CONCrete execution and symbOLIC execution, with the purpose of feasibility. 05] Many successful tools We present a preliminary evaluation of the time/state reduction using this method. A Survey of Approaches for Automated Unit Testing The output of a KLEE execution is a directory (in our case klee-out-0) containing the test cases generated by KLEE. We harness this ability of concretization in order to maximize coverage on code paths without SMT timeouts, making this a viable strategy for approaching crypto verification. This is surprising because the community be-lieves that symbolic and concolic executions are slow due to path explosion and constraint solving.Table 1shows ClassicalSymbolic Execution 2.Challengesof Symbolic Execution 3.ConcolicTesting 4. Solution: Concolic Execution. A Survey of Approaches for Automated Unit Testing PowerPoint Presentation. Summary of Symbolic Execution for Bug Finding Augment a program with appropriate assertions Symbolically execute a path Create formula representing path constraint and assertion failure Solve constraints with a solver A satisfying assignment, if found, is an input triggering a bug
Top 3 teams of the Cyber Grand Challenge used a combination of fuzzing and Symbolic Execution But performance problem with Symbolic execution engines 4 Efficient generation of symbolic queries. However, the overhead of concolic execution when analyzing a single program path is still very high, limiting the scalability of the approach. Dynamic Symbolic Execution (DSE) Known as Concolic Execution, as in concrete symbolic execution because this approach uses concrete state to drive the execution while maintaining symbolic state as metadata. From a theoretical perspective, exhaustive symbolic execution provides a sound Lecture 15: Dynamic Symbolic Execution (aka Directed Automated Random Testing, aka Concolic Execution). CACM, 19(7):385394, 1976. Unlike classical symbolic execution, since concolic execution maintains the entire concrete state of the program along an execution, it needs initial concrete values for its inputs. The Java Concolic Unit Testing Engine (jCUTE) automatically generates unit tests for Java programs. & random testing VERISOFT[8] Hybrid Concolic exec. Download Presentation. Concolic= Concrete + Symbolic. B. Symbolic and Concolic 8 33 It provides components like a taint engine, a dynamic symbolic execution engine, a snapshot engine, translation of x64 instruction to SMT2, a Z3 interface to solve constraints and Python bindings. Concolic execution IR and constraints solver Proof of concept End Bugs hunting White box Black box Pattern matching Dumb fuzzing In-memory fuzzing Manual vs automatic testing White box PHP 5.3.6 - Stack bu er over ow in socket connect (CVE-2011-1938) Jonathan Salwan Software testing and concolic execution These aws can cause various effects including the crashes, hanging or Enter Concolic execution Used to better take advantage of the underlying hardware The term concolic is a contraction of concrete symbolic I know, right? Debugging concolic execution is also much simpler. Concolic execution is a software testing technique that performs symbolic execution (using symbolic input values with sets of expressions, one expression per output variable) with concrete execution (testing on particular inputs) path. Concolic execution has shown to be extremely effective when paired with coverage-guided fuzzing in what is called a hybrid fuzzing setup. Entire execution tree, Search Strategies!! 06]vs. DART [Godefroidet al. Solution for jCute Symbolic execution or Concolic and Selenium UI testing tool.
To solve this problem, recent studies have proposed hybrid fuzzers that observe the context of a target program using symbolic execution; these fuzzers generate test cases to bypass the sanity check. However, there are two problems with this approach. To do: Generate test cases: Black-box test generation: Fuzzing, Random testing White-box test generation: Symbolic/Concolic execution 10 VS 11. Concolic execution Also called dynamic symbolic execution Instrument the program to do symbolic execution as the program runs I.e., shadow concrete program state with symbolic variables Explore one path, from start to completion, at a time Thus, always have a concrete underlying value to rely on 21 & state merging S2E[6] Hybrid Symbolic exec. Symbolic execution and program testing. Jun Sun, Singapore University of Technology and Design
A symbolic path is associated to a set of atomic path constraints; one has to pick and negate one constraint, which may in turn result in a new path explored and new constraints to be negated. Symbolic execution is a program analysis technique introduced in the 70s that has received renewed interest in recent years, due to algorithmic advances and increased availability of computational power and constraint solving technology. During concolic testing, we identify program regions that can be encoded by BMC on-the-fly so that program paths within these regions are checked simultaneously. GKLEE is the rst concolic verier and test generator tailored for GPU programs. View 17-SymbolicExecution.pdf from COMP COMP-511 at The Hong Kong University of Science and Technology. However, the overhead of concolic execution when analyzing a single program path is still very high, limiting the scalability of the approach. Symbolic execution alone is slow and gets stuck (state explosion, loops) Combining Fuzzing and concolic execution: best of both worlds? Early work on symbolic execution Robert S. Boyer, Bernard Elspas, and Karl N. Levitt. Grace and other concolic engines tackle this more methodically. The technique begins with a concrete execution of the program on an arbitrary input, building up a symbolic representation of the path as it runs.
The Concolic Testing Algorithm Classify input variables into symbolic / concrete Instrument to record symbolic vars and path conditions Choose an arbitrary input Execute the program Symbolically re-execute the program Negate the unexplored last path condition Is there an input satisfying constraint F T Dynamic Symbolic Execution 3 Received significant interest in the last few years Many dynamic symbolic execution/concolic tools available as open-source: CREST, KLEE, SYMBOLIC JPF, etc. At each loop iteration (lines 623), the function decodes the length of the current data element with get_length (line 8). 1. The term benchmark is also commonly utilized for the purposes of elaborately designed benchmarking programs themselves. Lecture 18: Part 1: Alloy Analyzer, and Part 2: Data Model Verification for Web Applications. Program is simultaneously executed with concrete and symbolic inputs . To alleviate this, S2E also implements concolic execution. Concolic execution works exactly as traditional symbolic execution: it propagates symbolic inputs through the system, allowing conditional branches to fork new paths whenever necessary. Thanks to organizers and ISSISP Concolic and Symbolic 8 One path at a time, simplify constraints! This is achieved through an exhaustive exploration of the possible execution states. Execution would then proceed with the multiplication and the conditional branch, which would evaluate to false and print OK. During symbolic execution, the program reads a symbolic value (e.g., ) and assigns it to y. To perform a symbolic or a concolic execution we must keep the data and the control flow of each program point.
We tackled the harder problem and produced two production-quality bug-finding systems: GRR, a high-throughput fuzzer, and PySymEmu (PSE), a binary symbolic executor with support for concrete inputs. Test generation and symbolic/concrete execution. Dynamic Symbolic Execution 3 Received significant interest in the last few years Many dynamic symbolic execution/concolic tools available as open-source: CREST, KLEE, SYMBOLIC JPF, etc. CS 267 Lecture Notes. Symbolic execution allows us to execute a program through all possible execution path s, thus achieving all possible path conditions (path condition = the set of logical constraints that takes us to a specific point in the execution). Expand Symbolic execution is a program analysis technique introduced in the 70s that has received renewed interest in recent years, due to algorithmic advances and increased availability of computational power and constraint solving technology. These can then be used for further symbolic exploration with KLEE or as concrete seed for fuzzing, e.g. We present SymCC, an LLVM-based C and C++ compiler that builds concolic execution right into the binary. Concolic execution is a mix between CONCrete execution and symbOLIC execution, with the purpose of feasibility. Symbolic execution allows us to execute a program through all possible execution paths, thus achieving all possible path conditions (path condition = the set of logical constraints that takes us to a specific point in the execution). Concolic execution is a mix between CONCrete execution and symbOLIC execution, with the purpose of feasibility. 05] Many successful tools We present a preliminary evaluation of the time/state reduction using this method. A Survey of Approaches for Automated Unit Testing The output of a KLEE execution is a directory (in our case klee-out-0) containing the test cases generated by KLEE. We harness this ability of concretization in order to maximize coverage on code paths without SMT timeouts, making this a viable strategy for approaching crypto verification. This is surprising because the community be-lieves that symbolic and concolic executions are slow due to path explosion and constraint solving.Table 1shows ClassicalSymbolic Execution 2.Challengesof Symbolic Execution 3.ConcolicTesting 4. Solution: Concolic Execution. A Survey of Approaches for Automated Unit Testing PowerPoint Presentation. Summary of Symbolic Execution for Bug Finding Augment a program with appropriate assertions Symbolically execute a path Create formula representing path constraint and assertion failure Solve constraints with a solver A satisfying assignment, if found, is an input triggering a bug
Top 3 teams of the Cyber Grand Challenge used a combination of fuzzing and Symbolic Execution But performance problem with Symbolic execution engines 4 Efficient generation of symbolic queries. However, the overhead of concolic execution when analyzing a single program path is still very high, limiting the scalability of the approach. Dynamic Symbolic Execution (DSE) Known as Concolic Execution, as in concrete symbolic execution because this approach uses concrete state to drive the execution while maintaining symbolic state as metadata. From a theoretical perspective, exhaustive symbolic execution provides a sound Lecture 15: Dynamic Symbolic Execution (aka Directed Automated Random Testing, aka Concolic Execution). CACM, 19(7):385394, 1976. Unlike classical symbolic execution, since concolic execution maintains the entire concrete state of the program along an execution, it needs initial concrete values for its inputs. The Java Concolic Unit Testing Engine (jCUTE) automatically generates unit tests for Java programs. & random testing VERISOFT[8] Hybrid Concolic exec. Download Presentation. Concolic= Concrete + Symbolic. B. Symbolic and Concolic 8 33 It provides components like a taint engine, a dynamic symbolic execution engine, a snapshot engine, translation of x64 instruction to SMT2, a Z3 interface to solve constraints and Python bindings. Concolic execution IR and constraints solver Proof of concept End Bugs hunting White box Black box Pattern matching Dumb fuzzing In-memory fuzzing Manual vs automatic testing White box PHP 5.3.6 - Stack bu er over ow in socket connect (CVE-2011-1938) Jonathan Salwan Software testing and concolic execution These aws can cause various effects including the crashes, hanging or Enter Concolic execution Used to better take advantage of the underlying hardware The term concolic is a contraction of concrete symbolic I know, right? Debugging concolic execution is also much simpler. Concolic execution is a software testing technique that performs symbolic execution (using symbolic input values with sets of expressions, one expression per output variable) with concrete execution (testing on particular inputs) path. Concolic execution has shown to be extremely effective when paired with coverage-guided fuzzing in what is called a hybrid fuzzing setup. Entire execution tree, Search Strategies!! 06]vs. DART [Godefroidet al. Solution for jCute Symbolic execution or Concolic and Selenium UI testing tool.