Squirrel Prover - Index (original) (raw)

The Squirrel Prover is a proof assistant dedicated to cryptographic protocols. It relies on a higher-order logic following the computationnally complete symbolic attacker approach. It thus provides guarantees in the computational model.

Getting started

A 13 minutes introduction to the basic concepts and core ideas of theSquirrel Prover can be found here.

A READMEprovides installation instructions.

You can also try our online version here.

Documentation

The documentation can be found here.

Tutorial

You may get started with this tutorial, or commented examples available in our browser-based prover. More complete tutorials have been prepared on the occasion of several summer schols; see the eventspage.

A high-level introduction to the theory behind Squirrel was published in the ACM Siglog newsletter [1]. The formal technical details are inside the research papers:

• the computationnally complete symbolic attacker was proposed in[2];
• the tool Squirrel was introduced in [3] as a proof assistant for a meta-logic on top of the logic of [2];
• the meta-logic was later adapted to support protocols with mutable state [4];
• a post-quantum sound variant of the logic, meta-logic and tool have been given in [5];
• recently, the meta-logic approach has been abandonned in favor of a self-contained higher-order logic [6].

Team

• David Baelde, ENS Rennes, Univ Rennes, CNRS, IRISA
• Stéphanie Delaune, Univ Rennes, CNRS, IRISA
• Caroline Fontaine, Université Paris-Saclay, CNRS, LMF
• Charlie Jacomme,Université de Lorraine, LORIA, Inria Nancy Grand-Est
• Adrien Koutsos, Inria Paris
• Joseph Lallemand, Univ Rennes, CNRS, IRISA
• Clément Herouard, Univ Rennes, CNRS, IRISA
• Justine Sauvage, Inria Paris

Former members:

• Tito Nguyen, formerly IRISA, now at LIS / Aix-Mariseille University
• Solène Moreau, formerly IRISA, now at AdaCore
• Thomas Rubiano, formerly Univ Rennes, CNRS, IRISA

Source code

Squirrel is an open source project, licensed under the MIT License. All source code is available here.

Publications

[1]

D. Baelde, S. Delaune, C. Jacomme, A. Koutsos, and J. Lallemand,“The Squirrel Prover and its Logic,” in ACM SIGLOG News, 2024, vol. 11, https://inria.hal.science/hal-04579038.

[2]

G. Bana and H. Comon-Lundh, “A Computationally Complete Symbolic Attacker for Equivalence Properties,” in_2014 ACM SIGSAC Conference on Computer and Communications Security_, 2014, pp. 609–620, https://hal.inria.fr/hal-01102216.

[3]

D. Baelde, S. Delaune, A. Koutsos, C. Jacomme, and S. Moreau, “AnInteractive Prover for Protocol Verification in the Computational Model,” in Proceedings of the 42ndIEEE Symposium on Security andPrivacy (S&P’21), 2021,https://hal.inria.fr/hal-03172119.

[4]

D. Baelde, S. Delaune, A. Koutsos, and S. Moreau, “Cracking the Stateful Nut,” in_CSF 2022 - 35th IEEE Computer Security Foundations Symposium_, 2022, https://hal.archives-ouvertes.fr/hal-03500056.

[5]

C. Cremers, C. Fontaine, and C. Jacomme, “A Logic and anInteractive Prover for theComputational Post-Quantum Security of Protocols,” in_Proceedings of the 43nd IEEE Symposium on Security and Privacy(S&P’22)_, 2022, https://hal.inria.fr/hal-03620358.

[6]

D. Baelde, A. Koutsos, and J. Lallemand, “A higher-order indistinguishability logic for cryptographic reasoning,” in_2023 38th annual ACM/IEEE symposium on logic in computer science (LICS)_, 2023, pp. 1–13, https://hal.inria.fr/hal-03981949.

[7]

D. Baelde, A. Koutsos, and J. Sauvage, “Foundations for cryptographic reductions in CCSA logics,” in_CCS_, 2024, pp. to appear, https://inria.hal.science/hal-04511718.

[8]

D. Baelde, C. Fontaine, A. Koutsos, G. Scerri, and T. Vignon, “A probabilistic logic for concrete security,” in_CSF_, 2024, pp. 324–339, https://inria.hal.science/hal-04577828.