Homepage of Claudio Orlandi

About me

A picture of me. — Photo by Sebastian Krog Knudsen for Partisia.

(Professional) Bio

I am a professor in the Crypto Group at Aarhus University.
Previously I worked as associate professor (2014-2023) and postdoc (2012-2014) at Aarhus University. Before that, I worked as postdoc at Bar-Ilan University with Yehuda Lindell (2011-2012). I got my PhD in 2011 at Aarhus Univeristy with Ivan Damgård and Jesper Buus Nielsen as my advisors.

Numbers

My profile on Google Scholar.
My Erdős number is 3 via Erdős - Pomerance - Damgård - Me. Unfortunately, my Bacon number is still undefined!
ORCID: 0000-0003-4992-0249

Contact Info

Address: Department of Computer Science, Aabogade 34, 8200 Aarhus, Denmark
Office: Nygaard 283
Email: orlandi at cs.au.dk
Phone: (+45) 21433249
Twitter: @claudiorlandi
Web: orlandi.dk

Research

Projects, Centers, etc.

DECRYPSYS - "Decentralized Cryptographic Systemsn" (ERC Consolidator Grant 2023)
CryptoDigi - "Cryptographic Foundations for Digital Society" (DFF-FNU Research Project 2 2023)
SPEC - "Secure, Private, Efficient Multiparty Computation" (ERC Starting Grant 2018)
DIREC (Danish National Centre for Research in Digital Technologies) - Workstream Leader for "Cybersecurity and Blockchains".
Concordium Blockcahin Research Center Aarhus - WP Lead Cryptography

Past Projects, Centers, etc.

BCM - WP Leader for "Center for Blockchains and Electronic Markets" (Carlsberg Foundation Semper Ardens 2019)
FoCC - "Foundations of Cryptographic Computing" (DFF-FNU Sapere Aude Starting Grant 2016)
CryptoAction - Chair of "Cryptography for Secure Digital Interaction" (COST Action IC 1306)
SODA - WP Leader for "Scalable Oblivious Data Analytics" (H2020 ICT-18-2016)
DIGIT - CyberSecurity WP Leader for "Aarhus University Centre for Digitalisation, Big Data and Data Analytics".
PRACTICE - "Privacy-Preserving Computation in the Cloud" (FP7 ICT-2013-10)
CTIC - Cryptography WP Leader for "Center for the Theory of Interactive Computation".
CryPSCo - "Cryptographic Protocols For Secure Computation" (DFF-FTP Individual Postdoc Grant 2011)

Manuscripts

Securely Computing One-Sided Matching Markets: James Hsin-Yu Chiang, Ivan Damgård, Claudio Orlandi, Mahak Pancholi, Mark Simkin; 2024. [ePrint].

Peer-Reviewed Publications

I believe that all scientific publications should be freely available online, given that researchers and peer-reviewers are largely supported by public funding. Therefore I am committed to make all my papers availabe to the general public. If there is a paper of mine you would like to read but do not have access to, please write me and I will be happy to share a copy with you.

Following the Hardy-Littlewood rule, the list of authors in most of my publications is sorted alphabetically, and not by contribution (exceptions: 1-4, 43; 14 is a mistake, as the last author should have been indexed by the "B" of Burra instead of S of "Sheshank". 58 corrects this mistake.).

79. Fiat-Shamir Bulletproofs are Non-Malleable (in the Random Oracle Model): Chaya Ganesh, Claudio Orlandi, Mahak Pancholi, Akira Takahashi, Daniel Tschudi; Journal of Cryptology, 2024. [ePrint]. (Full version of 64 with additional and improved results.)
78. Rate-1 Arithmetic Garbling from Homomorphic Secret-Sharing: Pierre Meyer, Claudio Orlandi, Lawrence Roy, Peter Scholl; TCC 2024. [ePrint].
77. An Improved Threshold Homomorphic Cryptosystem Based on Class Groups: Lennart Braun, Guilhem Castagnos, Ivan Damgård, Fabien Laguillaumie, Kelsey Melissaris, Claudio Orlandi, Ida Tucker; SCN 2024. [ePrint].
76. Differentially Private Selection from Secure Distributed Computing: Ivan Damgård, Hannah Keller, Boel Nelson, Claudio Orlandi, Rasmus Pagh; WWW 2024. [ePrint], [arXiv].
75. Improved Distributed RSA Key Generation Using the Miller-Rabin Test: Jakob Burkhardt, Ivan Damgård, Tore Frederiksen, Satrajit Ghosh, Claudio Orlandi; CCS 2023. [ePrint].
74. Two-Round Stateless Deterministic Two-Party Schnorr Signatures From Pseudorandom Correlation Functions: Yashvanth Kondi, Claudio Orlandi, Lawrence Roy; CRYPTO 2023. [ePrint].
73. Secure Multiparty Computation from Threshold Encryption based on Class Groups: Lennart Braun, Ivan Damgård, Claudio Orlandi; CRYPTO 2023. [ePrint].
72. MPC with Low Bottleneck-Complexity: Information-Theoretic Security and More: Hannah Keller, Claudio Orlandi, Anat Paskin-Cherniavsky, Divya Ravi; ITC 2023. [ePrint].
71. Witness-Succinct Universally-Composable SNARKs: Chaya Ganesh, Yashvanth Kondi, Claudio Orlandi, Mahak Pancholi, Akira Takahashi, Daniel Tschudi; EUROCRYPT 2023. [ePrint].
70. Structure-Preserving Compilers from New Notions of Obfuscations: Matteo Campanelli, Danilo Francati, Claudio Orlandi; PKC 2023. [ePrint].
69. Laconic Private Set-Intersection From Pairings: Diego Aranha, Chuanwei Lin, Claudio Orlandi, Mark Simkin; CCS 2022. [ePrint].
68. Zero-Knowledge for Homomorphic Key-Value Commitments with Applications to Privacy-Preserving Ledgers: Matteo Campanelli, Felix Engelmann, Claudio Orlandi; SCN 2022. [ePrint].
67. On Access Control Encryption without Sanitization: Cecilia Boschini, Ivan Damgård, Claudio Orlandi; SCN 2022. [ePrint].
66. An Algebraic Framework for Silent Preprocessing with Trustless Setup and Active Security: Damiano Abram, Ivan Damgård, Claudio Orlandi, Peter Scholl; CRYPTO 2022. [ePrint].
65. Low-Bandwidth Threshold ECDSA via Pseudorandom Correlation Generators: Damiano Abram, Ariel Nof, Claudio Orlandi, Peter Scholl, Omer Shlomovits; IEEE Symposium on Security and Privacy 2022. [ePrint].
64. Fiat-Shamir Bulletproofs are Non-Malleable (in the Algebraic Group Model): Chaya Ganesh, Claudio Orlandi, Mahak Pancholi, Akira Takahashi, Daniel Tschudi; EUROCRYPT 2022. [ePrint].
63. ECLIPSE: Enhanced Compiling method for Pedersen-committed zkSNARK Engines: Diego F. Aranha, Emil Madsen Bennedsen, Matteo Campanelli, Chaya Ganesh, Claudio Orlandi, Akira Takahashi; PKC 2022. [ePrint].
62. On the Bottleneck Complexity of MPC with Correlated Randomness: Claudio Orlandi, Peter Scholl, Divya Ravi; PKC 2022. [ePrint].
61. Virtual ASICs: Generalized Proof-of-Stake Mining in Cryptocurrencies: Chaya Ganesh, Claudio Orlandi, Daniel Tschudi, Aviv Zohar; CBT 2021. [ePrint]. [Video (short)], [Video (long)].
60. Improved Threshold Signatures, Proactive Secret Sharing and Input Certification from LSS Isomorphisms: Diego Aranha, Anders Dalskov, Daniel Escudero, Claudio Orlandi; LATINCRYPT 2021. [ePrint].
59. Stronger Notions and a More Efficient Construction of Threshold Ring Signatures: Alexander Munch-Hansen, Claudio Orlandi, Sophia Yakoubov; LATINCRYPT 2021. [ePrint].
58. High Performance Multi-Party Computation for Binary Circuits Based on Oblivious Transfer: Sai Sheshank Burra, Enrique Larraia, Jesper Buus Nielsen, Peter Sebastian Nordholt, Claudio Orlandi, Emmanuela Orsini, Peter Scholl, Nigel P. Smart; Journal of Cryptology, 2021. [ePrint].
57. Balancing Privacy and Accountability in Blockchain Identity Management: Ivan Damgård, Chaya Ganesh, Hamidreza Khoshakhlagh, Claudio Orlandi, Luisa Siniscalchi; CT-RSA 2021. [ePrint].
56. Two-round n-out-of-n and Multi-Signatures and Trapdoor Commitment from Lattices: Ivan Damgård, Claudio Orlandi, Akira Takahashi, Mehdi Tibouchi; PKC 2021 and Invited to Journal of Cryptology, 2022. [ePrint]. [Video].
55. The Rise of Paillier: Homomorphic Secret Sharing and Public-Key Silent OT: Claudio Orlandi, Peter Scholl, Sophia Yakoubov.; EUROCRYPT 2021. [ePrint].
54. Refresh When You Wake Up: Proactive Threshold Wallets with Offline Devices: Yashvanth Kondi, Bernardo Magri, Claudio Orlandi, Omer Shlomovits; IEEE Symposium on Security and Privacy 2021. [ePrint], [Video]
53. Stronger Security and Constructions of Multi-Designated Verifier Signatures: Ivan Damgård, Helene Haagh, Rebekah Mercer, Anca Nițulescu, Claudio Orlandi, Sophia Yakoubov; TCC 2020. [ePrint].
52. Securing DNSSEC Keys via Threshold ECDSA From Generic MPC: Anders Dalskov, Marcel Keller, Claudio Orlandi, Kris Shrishak, Haya Shulman; ESORICS 2020. [ePrint]. [Video].
51. Secure Generalized Deduplication via Multi-Key Revealing Encryption: Daniel Lucani, Lars Nielsen, Claudio Orlandi, Elena Pagnin, Rasmus Vestergaard; SCN 2020. [ePrint].[Video].
50. Black-Box Transformations from Passive to Covert Security with Public Verifiability: Ivan Damgård, Claudio Orlandi, Mark Simkin; CRYPTO 2020. [ePrint], [Video].
49. Optimal Transport Layer for Secure Computation: Markus Brandt, Claudio Orlandi, Kris Shrishak, Haya Shulman; SECRYPT 2020. [ePrint].
48. Use your Brain! Arithmetic 3PC For Any Modulus with Active Security (New version!): Hendrik Eerikson, Marcel Keller, Claudio Orlandi, Pille Pullonen, Joonas Puura, Mark Simkin; Information-Theoretic Cryptography (ITC) 2020. [ePrint], [Video].
47. Security of Hedged Fiat-Shamir Signatures under Fault Attacks: Diego F. Aranha, Claudio Orlandi, Akira Takahashi, Greg Zaverucha; EUROCRYPT 2020. [ePrint], [Video].
46. Commodity-Based 2PC for Arithmetic Circuits: Ivan Damgård, Helene Haagh, Michael Nielsen, Claudio Orlandi; IMA Cryptography and Coding 2019. [ePrint], [code].
45. QuisQuis: A New Design for Anonymous Cryptocurrencies: Prastudy Fauzi, Sarah Meiklejohn, Rebekah Mercer, Claudio Orlandi; ASIACRYPT 2019. [ePrint].
44. Sharing Information with Competitors: Simina Brânzei, Claudio Orlandi, Guang Yang; SAGT 2019. [arXiv].
43. TOPPool: Time-aware Optimized Privacy-Preserving Ridesharing: Elena Pagnin, Gunnar Gunnarsson, Pedram Talebi, Claudio Orlandi, Andrei Sabelfeld; Privacy Enhancing Technologies 2019. [ePrint].
42. Proofs of Replicated Storage Without Timing Assumptions: Ivan Damgård, Chaya Ganesh, Claudio Orlandi; CRYPTO 2019. [ePrint]. [Video].
41. Proof-of-Stake Protocols for Privacy-Aware Blockchains: Chaya Ganesh, Claudio Orlandi, Daniel Tschudi; EUROCRYPT 2019. [ePrint].
40. Combining Private Set-Intersection with Secure Two-Party Computation: Michele Ciampi and Claudio Orlandi; SCN 2018. [ePrint].
39. Yet Another Compiler for Active Security or: Efficient MPC Over Arbitrary Rings: Ivan Damgård, Claudio Orlandi, Mark Simkin; CRYPTO 2018. [ePrint].
38. Can You Trust Your Encrypted Cloud? An Assessment of SpiderOakONE's Security: Anders P. K. Dalskov, Claudio Orlandi; AsiaCCS 2018. [ePrint].
37. Revealing Encryption for Partial Ordering: Helene Haagh, Yue Ji, Chenxing Li, Claudio Orlandi, and Yifan Song; IMA Cryptography and Coding 2017. [ePrint].
36. Post-Quantum Zero-Knowledge and Signatures from Symmetric-Key Primitives: Melissa Chase, David Derler, Steven Goldfeder, Claudio Orlandi, Sebastian Ramacher, Christian Rechberger, Daniel Slamanig, Greg Zaverucha; CCS 2017. [ePrint]. [GitHub] (merge of ePrint 2016/1085 and ePrint 2016/1110).; The signature scheme described in this paper has been submitted submitted for the NIST Post-Quantum Cryptography Standardization under the name Picnic.
35. PrivatePool: Privacy-Preserving Ridesharing: Per Hallgreen, Claudio Orlandi, Andrei Sabelfeld; CSF 2017. [PDF]
34. Security of Symmetric Primitives under Incorrect Usage of Keys: Pooya Farshim, Claudio Orlandi, Răzvan Roşie; FSE 2017. [ePrint]
33. Access Control Encryption for Equality, Comparison, and More: Georg Fuchsbauer, Romain Gay, Lucas Kowalczyk, Claudio Orlandi; PKC 2017. [ePrint].
32. Cross&Clean: Amortized Garbled Circuits with Constant Overhead: Jesper Buus Nielsen, Claudio Orlandi; TCC 2016-B. [ePrint].
31. Access Control Encryption: Enforcing Information Flow with Cryptography: Ivan Damgård, Helene Haagh, Claudio Orlandi; TCC 2016-B. [ePrint], [arXiv] .
30. On the CCA (in)security of MTProto: Jakob Jakobsen, Claudio Orlandi; SPSM@CCS 2016. [ePrint], [ACM Authorizer]. Featured in: [Motherboard], [Version2] [The Atlantic]
29. ZKBoo: Faster Zero-Knowledge for Boolean Circuits: Irene Giacomelli, Jesper Madsen, Claudio Orlandi; USENIX Security Symposium 2016. [ePrint]. Best Student Paper Award!.
28. Non-Interactive Verifiable Secret Sharing For Monotone Circuits: Ge Bai, Ivan Damgård, Claudio Orlandi, Yu Xia; AFRICACRYPT 2016. [ePrint] .
27. How to Bootstrap Anonymous Communication: Sune K. Jakobsen, Claudio Orlandi; ITCS 2016. [arXiv], [ePrint] .
26. The Simplest Protocol for Oblivious Transfer: Tung Chou, Claudio Orlandi; LATINCRYPT 2015. [ePrint], [code].
25. Privacy-Free Garbled Circuits with Applications To Efficient Zero-Knowledge: Tore Kasper Frederiksen, Jesper Buus Nielsen, Claudio Orlandi; EUROCRYPT 2015. [ePrint].
24. Privacy-Enhancing Overlays in Bitcoin: Sarah Meiklejohn, Claudio Orlandi; 2nd Workshop on Bitcoin Research, 2015. [Workshop Homepage].
23. A Framework for Outsourcing of Secure Computation: Thomas P Jakobsen, Jesper Buus Nielsen, Claudio Orlandi; ACM Cloud Computing Security Workshop 2014; The proceeding version contains errors, please use the revised version instead: [ePrint].
22. Obfuscation ==> (IND-CPA Security =/=> Circular Security): Antonio Marcedone, Claudio Orlandi; SCN 2014. [ePrint].
21. Publicly Auditable Secure Multi-Party Computation: Carsten Baum, Ivan Damgård, Claudio Orlandi; SCN 2014. [ePrint].
20. Statistical Concurrent Non-Malleable Zero Knowledge: Claudio Orlandi, Rafail Ostrovsky, Vanishree Rao, Amit Sahai, Ivan Visconti; TCC 2014. [ePrint].
19. Hiding The Input Size in Secure Two-Party Computation: Yehuda Lindell, Kobbi Nissim, Claudio Orlandi; ASIACRYPT 2013. [ePrint]
18. Zero-Knowledge Using Garbled Circuits: How To Prove Non-Algebraic Statements Efficiently: Marek Jawurek, Florian Kerschbaum, Claudio Orlandi; ACM CCS 2013. [ePrint].
17. MiniLEGO: Efficient Secure Two-Party Computation From General Assumptions: Tore Frederiksen, Thomas P Jakobsen, Jesper Buus Nielsen, Peter Sebastian Nordholt, Claudio Orlandi; EUROCRYPT 2013. [ePrint].
16. On the Power of Correlated Randomness in Secure Computation: Yuval Ishai, Eyal Kushilevitz, Sigurd Meldgaard, Claudio Orlandi, Anat Paskin-Cherniavsky,; TCC 2013. [draft].
15. Calling out Cheaters: Covert Security with Public Verifiability: Gilad Asharov, Claudio Orlandi; ASIACRYPT 2012. [ePrint].
14. A New Approach to Practical Active-Secure Two-Party Computation: Jesper Buus Nielsen, Peter Sebastian Nordholt, Claudio Orlandi, Sai Sheshank Burra; CRYPTO 2012. [ePrint]. [arXiv].
13. Privacy-Aware Mechanism Design: Kobbi Nissim, Claudio Orlandi, Rann Smorodinsky; ACM Conference on Electronic Commerce 2012. [arXiv].
12. Lower and Upper Bounds for Deniable Public-Key Encryption: Rikke Bendlin, Jesper Buus Nielsen, Peter Sebastian Nordholt, Claudio Orlandi; ASIACRYPT 2011. [ePrint].; First appeared as a preprint under the title "Receiver-deniable public-key encryption is impossible"
11. Is Multiparty Computation Any Good In Practice?: Claudio Orlandi; ICASSP 2011. [draft].
10. Semi-Homomorphic Encryption and Multiparty Computation: Rikke Bendlin, Ivan Damgård, Claudio Orlandi, Sarah Zakarias; EUROCRYPT 2011. [ePrint].
9. On Invertible Sampling and Adaptive Security: Yuval Ishai, Abhishek Kumarasubramanian, Claudio Orlandi, Amit Sahai; ASIACRYPT 2010. [draft].
8. Multiparty Computation for Dishonest Majority: from Passive to Active Security at Low Cost: Ivan Damgård, Claudio Orlandi; CRYPTO 2010. [ePrint].
7. On the Necessary and Sufficient Assumptions for UC Computation: Ivan Damgård, Jesper Buus Nielsen, Claudio Orlandi; TCC 2010. [ePrint].
6. LEGO for Two Party Secure Computation: Jesper Buus Nielsen, Claudio Orlandi; TCC 2009. [ePrint].
5. Essentially Optimal Universally Composable Oblivious Tranfer: Ivan Damgård, Jesper Buus Nielsen Claudio Orlandi; ICISC 2008. [ePrint].
4. Enhancing Privacy in Remote Data Classification: Alessandro Piva, Claudio Orlandi, Mauro Caini, Tiziano Bianchi, Mauro Barni; SEC 2008.
3. Oblivious Neural Network Computing from Homomorphic Encryption,: Claudio Orlandi, Alessandro Piva, Mauro Barni; EURASIP JIS, 2007, Special Issue on Signal Processing in the Encrypted Domain.
2. A Privacy Preserving Protocol for Neural-Network-Based Computation: Mauro Barni, Claudio Orlandi, Alessandro Piva; MM&Sec 2006. [ACM Author-Izer Service]
1. Zero-knowledge ST-DM Watermarking: Alessandro Piva, Vito Cappellini, Daniele Corazzi, Alessia De Rosa, Claudio Orlandi, Mauro Barni; SPIE Electronic Imaging 2006. Security, Steganography, and Watermarking of Multimedia Contents VIII.

Teaching and Supervision

Postdocs

Current:

Past:

Danilo Francati, now Assitant Professor at Royal Holloway, London.
Yash Kondi, now Principal Scientist at Silence Laboratories.
Divya Ravi, now Assistant Professor at University of Amsterdam, Netherlands.
Akira Takahashi, Senior Research Scientist at J.P. Morgan.
Matteo Campanelli, now Research Scientist at Matter Labs.
Eduardo Soria-Vazquez, now senior cryptographer at Technology Innovation Institute (TII).
Prastudy Fauzi, now Research Fellow at NTU
Chaya Ganesh, now Assistant Professor at Indian Institute of Science
Anca Nitulescu, now Applied Cryptography Researcher at IOHK
Peter Scholl, now Associate Professor at Aarhus University
Guang Yang, now Research Director at Conflux

PhD Students

I have/had the honour to be the main PhD advisor of:

Current:

Past:

Mahak Pancholi, graduated 2024, now VILLUM International Postdoc at IMDEA
Akira Takahashi, graduated 2022, now Senior Research Scientist at J.P. Morgan.
Anders P.K. Dalskov, graduated 2020, now Cryptographic Engineer at Partisia
Helene Flyholm Haagh, graduated 2019, Software Engineer at Cryptomathic

I have also been involved in the supervision of: Sebastian Kolby, Nikolas Melissaris, Lennart Braun, Alexander Munch-Hansen, Rahul Rachuri, Rebekah Mercer, Mark Simkin (Recipient of EliteForsk PhD Grant), Satrajit Ghosh.

Master Students

See here for information about master thesis supervision.

Aarhus University

Bachelor level: Secure Distributed Systems (2018+), Distributed Systems (2017).
Master level: Cryptographic Computing (2013+): Lecture Notes
IT-Vest Master in IT-Security: Introduction to IT Security (2015+), Cryptography (2015+).

Invited Talks, Tutorials, etc.

Activites

Program Committee Member

CRYPTO 2025, CRYPTO 2021, CRYPTO 2020, CRYPTO 2017, CRYPTO 2014,
PKC 2025 (Area Chair for MPC & Friends), PKC 2013,
EUROCRYPT 2024 (Area Chair for Multi-Party Computation and Zero-Knowledge), EUROCRYPT 2021, EUROCRYPT 2019, EUROCRYPT 2016,
CT-RSA 2023, CT-RSA 2018
ACM CCS 2022 (Area Chair for Appiled Cryptography), ACM CCS 2019, ACM CCS 2016
CRYPTO 2021, CRYPTO 2020, CRYPTO 2017, CRYPTO 2014,
CFAIL 2021, CFAIL 2019: A Conference for Failed Approaches and Insightful Losses in Cryptology
(Po)PETS 2019, (Po)PETS 2015, PETS 2014, PETS 2013,
Blockchain 2018,
TCC 2016-A, TCC 2014,
ACNS 2016,
ICITS 2015,
Financial Crypto 2015, Financial Crypto 2013,
SCN 2014,
BalkanCryptSec 2014,
INSCRYPT 2014, INSCRYPT 2013, INSCRYPT 2012
CANS 2013, CANS 2012,
ProvSec 2012, ProvSec 2011,
ACISP 2012, ACISP 2011,

Organization of Events, Workshops, Schools, ...

Ongoing:

Theory and Practice of Secure Multiparty Computation (since 2012),

Past: Theory and Practice of Blockchains (since 2019); CryptoAction Symposia: Sutomore 2018, Amsterdam 2017, Budapest 2016; CryptoAction Schools: Symmetric Cryptography and Blockchain Torremolinos 2018, Multilinear Maps and FHE Paris 2015, Cryptographic Attacks Porto 2014; Symposium on the work of Ivan Damgård, Aarhus 2016; China Theory Week 2013, Aarhus 2013; New Trends in Mechanism Design II, Aarhus 2013; Bar-Ilan Winter School on Lattice-Based Cryptogrpahy, Tel Aviv 2012;

Misc

History of the Crypto Group in Aarhus.
Slides from lecture on Backdoors in Cryptography
Slides from lecture on Cryptographic Currencies
My research in a nutshell (old poster from my PhD times!).

Last update: Tuesday, 22nd October, 2024, 09:24am