© Andrew IrelandDependable Systems Group ITI Techmedia and Technology Transfer Andrew Ireland Dependable Systems Group School of Mathematical & Computer Sciences Heriot-Watt University Edinburgh

© Andrew IrelandDependable Systems Group The Story So Far … NuSPADE and SPADEase A follow-on knowledge transfer project – EPSRC RAIS Scheme (CTA GR/T11289/01) Embedded Bill Ellis (RA) within Praxis for 6 months SPADEase: extends SPADE Simplifier with the proof planning (and program analysis) techniques prototyped via NuSPADE

© Andrew IrelandDependable Systems Group ITI Techmedia Aims to bring Scotland to the forefront of the global market for digital media and communications technology Pseudo-venture capitalists, sponsored by Scottish Executive Funding level for projects: £3M to £10M Return on funding: ITI own IP arising from technology transfer phase

© Andrew IrelandDependable Systems Group Big Picture

© Andrew IrelandDependable Systems Group The Proposal Automated Security Engineering: a suite of related technologies that aim to ensure key security properties of software systems by automatic analysis and certification Techniques: advanced type inference, proof carrying resource guarantees, security protocols analysis, proof planning and program analysis

© Andrew IrelandDependable Systems Group The Players Mobile Resource Guarantee: Don Sannella Mathematical Reasoning Group: Alan Bundy Dependable Systems Group: Andrew Ireland

© Andrew IrelandDependable Systems Group Progress To Date Technology Opportunity Review – Howard Chivers (Cranfield) Review covered background technology and fact gathering from university partners and potential partner companies Positive outcome, focus on proof planning and software verification in the first instance

© Andrew IrelandDependable Systems Group The SPARK Approach Supports data & information flow analysis and formal verification via code level annotations Supports “correctness-by-construction” and is advocated by US National Cyber Security Partnership (April 2004) Applications include SHOLIS: UK MoD’s first Def Standard project

© Andrew IrelandDependable Systems Group Commonality in “New Wave” Focus on property based reasoning Mechanized abstraction Greater integration of reasoning tools

© Andrew IrelandDependable Systems Group The SPARK Approach A subset of Ada that eliminates potential ambiguities and insecurities (Praxis) Supports data & information flow analysis and formal verification via code level annotations Supports “correctness-by-construction” and is advocated by US National Cyber Security Partnership (April 2004) Applications include SHOLIS: UK MoD’s first Def Standard project

© Andrew IrelandDependable Systems Group NuSPADE Results Our evaluation was based upon examples drawn from industrial data provided by Praxis, e.g. SHOLIS SPADE Simplifier is very effective on exception freedom VC, i.e. typical hit-rate of 92% NuSPADE targeted the VCs which the SPADE Simplifier failed to prove, i.e. loop-based code While critical software is engineered to minimize the number and complexity of loops, we found that 80% of the loops we encountered were provable using NuSPADE

© Andrew IrelandDependable Systems Group What Next? Looking to deploy SPADEase during a “live” SPARK development project Longer term – we see SPADEase helping to shape the next generation of SPADE proof tools

© Andrew IrelandDependable Systems Group Future Horizons Mechanized Proof Tactic Adaption for Dependable Systems Evolution – MOD/EPSRC/QinetiQ Trusted software components in SPARK – collaboration with Kung-Kiu Lau and Praxis Perfect Developer – Heriot-Watt summer student in collaboration with Escher Technologies Reasoning about pointer programs: Lilia’s focus on description logics and bounded model checking (CSL05 and SEFM05); Andrew’s focus on separation logic and proof planning.

© Andrew IrelandDependable Systems Group Related Projects Mechanized Extraction & Analysis of Real-time Properties: Ben Gorry (research student) EPSRC Industrial Case Studentship with QinetiQ Andrew Ireland & Peter King Verifying the Correctness of HUME programs : Gudmond Grov (research student) Andrew Ireland & Greg Michaelson EU EmBounded Project – “Automatic Prediction of Resource Bounds for Embedded Systems” – Heriot-Watt, St Andrews, Ludwig Maximillian, Blaise-Pascal, AbsInt GmbH E1.5M

© Andrew IrelandDependable Systems Group Conclusion A new wave of formal verification tools is emerging - integrated tools that support property based verification of software NuSPADE and SPADEase are part of this “new wave” SPADEase in particular has demonstrated that proof planning can make an impact within industry