distributed systems research group automated verification of software thesis progress report...

DISTRIBUTED SYSTEMS RESEARCH GROUPhttp://dsrg.mff.cuni.cz

Automated Verification of Softwarethesis progress report

Ondřej ŠerýAdvisor: František Plášil

Ondřej Šerý: Automated Verification of Software 2

Problem statement

Problem:

“Slow adoption of automated software verification in industry”


Thesis: Automated Software Verification

Problem“Slow adoption of automated software verification in industry”

• Scaling• Low user-friendliness of the tools

Usually no GUI, LTL properties, hard-to-master spec. lang.• Hard to assess and choose a particular tool

No general set of test/benchmarks No competition (like SAT-COMP and SMT-COMP) Few (successful) case studies

• Missing methodology How to apply the techniques in the SW development cycle?

• Appropriate education missing Trend to decrease amount of math and logic in CS education Few special lectures devoted to this problem No comprehensive textbook on code model checking and deductive verification

Goal• Comprehensive summary of the field

Code Model Checking + Deductive Verification• Inclusion of 3-4 related (co)authored papers

[3]

[4]

[1][2]Cunning plan: reuse some of the text

in a NSWI132 textbook… some day…


Outline

1 Introduction2 State-of-the-art

2.1 Code Model Checking2.2 Explicit State Code Model Checking2.3 Abstraction Based Code Model Checking2.4 Mixed Approaches2.5 Deductive Verification2.6 Other techniques2.7 Case Studies

3 Collection of Papers4 Evaluation5 Future Work6 ConclusionReferences


Explicit State Code Model Checking

Key Idea Explicit representation of the program state

Tools Java PathFinder, MoonWalker, CMC, Zing, dSPIN

Topics Basics State Storage and Matching

• Collapsing Full States• State Symmetries• Incremental Heap Canonicalization

State Space Reductions• Partial Order Reduction• Summaries• Symbolic Execution


Abstraction Based Code Model Checking

Key Idea Predicate abstraction, counter-example guided abstraction

refinement

Tools SLAM, BLAST, SATABS, CBMC

Topics Basics Lazy Abstraction Local Predicates Lazy Shape Abstraction Specification Languages Termination


Mixed Approaches

Key Idea Mixing explicit state and abstraction based

model checking

Topics Synergy (YOGI) Predicate Abstraction with Under-

Approximation Refinement Dynamic Precision Adjustment (BLAST) Dynamic Analysis (PEX, CHESS)


Deductive Verification

Key Ideas Based on Hoare reasoning Heavy use of automated provers

Tools Java: JML .NET: Spec#, Code Contracts C: ACSL (FramaC), VCC

Topics Basics Heap Concurrency and Ownership Object Protocols

Collection of Papers

[1] Kofron, J., Parizek, P., Sery, O.: On Teaching Formal Methods: Behavior Models and Code Analysis, Accepted for publication in Proceedings of the 2nd International FME Conference on Teaching Formal Methods (TFM 2009), LNCS 5846, Nov 2009

[2] Kebrt, M., Sery, O.: UnitCheck: Unit Testing and Model Checking Combined, Accepted for publication in Proceedings of the 7th International Symposium on Automated Technology for Verification and Analysis (ATVA'09), LNCS, Oct 2009

[3] Kolb, E., Sery, O., Weiss, R.: Applicability of the BLAST Model Checker: An Industrial Case Study, Accepted for publication in Post-proceedings of PSI'09, LNCS, Apr 2009

[best PC score award]

[4] Sery, O.: Enhanced Property Specification and Verification in BLAST, In Proceedings of FASE 2009, LNCS 5503, pp. 456-469, York, UK, Mar 2009

[5] Kofron, J., Poch, T., Sery, O.: Making Components Fit: SPINing, In Proceedings of 32nd Software Engineering Workshop, IEEE, ISBN 978-0-7695-3617-0, pp. 65-74, Greece, Jan 2009

[6] Kofron, J., Plasil, F., Sery, O.: Modes in component behavior specification via EBP and their application in product lines, In Information and Software Technology 51/1, pp. 31-41, Elsevier, Jan 2009

[7] Kofron, J., Poch, T., Sery, O.: TBP: Code-Oriented Component Behavior Specification, In Proceedings of 32nd Software Engineering Workshop, IEEE, ISBN 978-0-7695-3617-0, pp. 75-83, Greece, Jan 2009

[8] Bulej, L., Bures, T., Thierry Coupaye, Decky, M., Jezek, P., Parizek, P., Plasil, F., Poch, T., Nicolas Rivierre, Sery, O., Tuma, P.: CoCoME in Fractal, Chapter in The Common Component Modeling Example: Comparing Software Component Models, Springer-Verlag, LNCS 5153, Aug 2008

[9] Bures, T., Decky, M., Hnetynka, P., Kofron, J., Parizek, P., Plasil, F., Poch, T., Sery, O., Tuma, P.: CoCoME in SOFA, Chapter in The Common Component Modeling Example: Comparing Software Component Models, Springer-Verlag, LNCS 5153, Aug 2008

[10] Sery, O., Plasil, F.: Slicing of Component Behavior Specification with Respect to Their Composition, In Proceedings of 10th International ACM SIGSOFT Symposium on Component-Based Software Engineering (CBSE 2007), LNCS 4608, Jul 2007

…Ondřej Šerý: Automated Verification of Software 9

Enhanced Property Specification and Verification in BLAST


Šerý O.FASE 2009, York (UK)

Ondřej ŠerýDSRG Seminar 5th March 2008 11

Blast spec. language

global int locked = 0;

event { pattern { lock(); } guard { locked == 0 } action { locked = 1; }}

event { pattern { unlock(); } guard { locked == 1 } action { locked = 0; }}

int a = 3;

void f() { lock(); a++; unlock();}

int locked = 0;int a = 3;

void f() { if (!(locked == 0)) {

assert(0); } locked = 1; lock();

a++;

if (!(locked == 1)) {assert(0);

} locked = 0; unlock();}

Predicates to be found & tracked

theorem prover calls

Ondřej ŠerýDSRG Seminar 5th March 2008 12

Blast & BP

(!lock; !unlock)*

int a = 3;

void f() { lock(); a++; unlock();}

1 2!lock^

BP:3 4

?lock$ !unlock^

?unlock$

1

1

1

3

3

1

Pros:• Marking the error states

No changes in the input C code No new predicates

• Differentiates among states• No laziness in the important properties

Cons:• Strictly weaker in expressive power

FSM vs. TM

Applicability of the BLAST Model Checker: An Industrial Case Study


Kolb, E., Šerý, O., Weiss, R. PSI 2009, Novosibirsk

OPC UA

OLE for Process Control - Unified Architecture Standardized by OPC Foundation

• www.opcfoundation.org

Platform- and Network-independent communication• Field Devices, Control Systems, Manufacturing Execution

Systems, and Enterprise Resource Planning Systems

Language bindings• C/C++, Java, .NET


OPC UA C-Stack

• Implementation for the C language Developed at ABB ~150 KLOC of ANSI C Designed for both PC-based

and embedded systems


Results summary (1/2)

Locking policy:


Results summary (2/2)

MessageContext management:

Encoder management:


UnitCheck: Unit Testing and Model Checking Combined


Kebrt, M., Sery, O. ATVA 2009, Macau

UnitCheck

Problem• Missing methodology for application of code

model checking

Key idea• Exhaustively explore state space of unit tests• In JUnit: JVM Java PathFinder

Benefit• Developer can use the same interface while

getting more confidence


Thank you for your attention

Questions?

[email protected]

Aswers also at:


distributed systems research group automated verification of software thesis progress report...

Documents

code analysis

fieldcode model

code contractsc

deductive verification2

outline1 introduction2

teaching formal methods

mixed approaches2

nswi132 textbook