Eagle: Efficient Privacy Preserving Smart Contracts

Carsten Baum, James Hsin yu Chiang, Bernardo David, Tore Kasper Frederiksen

Research output: Chapter in Book/Report/Conference proceedingConference contributionpeer-review


The proliferation of Decentralised Finance (DeFi) and Decentralised Autonomous Organisations (DAO), which in current form are exposed to front-running of token transactions and proposal voting, demonstrate the need to shield user inputs and internal state from the parties executing smart contracts. In this work we present “Eagle”, an efficient UC-secure protocol which efficiently realises a notion of privacy preserving smart contracts where both the amounts of tokens and the auxiliary data given as input to a contract are kept private from all parties but the one providing the input. Prior proposals realizing privacy preserving smart contracts on public, permissionless blockchains generally offer a limited contract functionality or require a trusted third party to manage private inputs and state. We achieve our results through a combination of secure multi-party computation (MPC) and zero-knowledge proofs on Pedersen commitments. Although other approaches leverage MPC in this setting, these incur impractical computational overheads by requiring the computation of cryptographic primitives within MPC. Our solution achieves security without the need of any cryptographic primitives to be computed inside the MPC instance and only require a constant amount of exponentiations per client input.

Original languageEnglish
Title of host publicationFinancial Cryptography and Data Security - 27th International Conference, FC 2023, Revised Selected Papers
EditorsFoteini Baldimtsi, Christian Cachin
PublisherSpringer Science and Business Media Deutschland GmbH
Number of pages19
ISBN (Print)9783031477539
StatePublished - 2024
Externally publishedYes
Event27th International Conference on Financial Cryptography and Data Security, FC 2023 - Bol, Croatia
Duration: 1 May 20235 May 2023

Publication series

NameLecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics)
ISSN (Print)0302-9743
ISSN (Electronic)1611-3349


Conference27th International Conference on Financial Cryptography and Data Security, FC 2023

Bibliographical note

Publisher Copyright:
© 2024, International Financial Cryptography Association.


  • Blockchain
  • DeFi
  • MPC
  • Privacy


Dive into the research topics of 'Eagle: Efficient Privacy Preserving Smart Contracts'. Together they form a unique fingerprint.

Cite this