Paper 2019/471

UC-Secure CRS Generation for SNARKs

Behzad Abdolmaleki, Karim Baghery, Helger Lipmaa, Janno Siim, and Michal Zajac


Zero-knowledge SNARKs (zk-SNARKs) have recently found various applications in verifiable computation and blockchain applications (Zerocash), but unfortunately they rely on a common reference string (CRS) that has to be generated by a trusted party. A standard suggestion, pursued by Ben Sasson et al. [IEEE S&P, 2015], is to generate CRS via a multi-party protocol. We enhance their CRS-generation protocol to achieve UC-security. This allows to safely compose the CRS-generation protocol with the zk-SNARK in a black-box manner with the insurance that the security of the zk-SNARK is not influenced. Differently from the previous work, the new CRS-generation protocol also avoids the random oracle model which is typically not required by zk-SNARKs themselves. As a case study, we apply the protocol to the state-of-the-art zk-SNARK by Groth [EUROCRYPT, 2016].

Available format(s)
Publication info
Published elsewhere. Minor revision. AFRICACRYPT 2019
CRS modelSNARKsubversion-securityUC security
Contact author(s)
jannosiim @ gmail com
helger lipmaa @ ut ee
karim baghery @ ut ee
behzad abdolmaleki @ ut ee
m p zajac @ gmail com
2019-05-10: received
Short URL
Creative Commons Attribution


      author = {Behzad Abdolmaleki and Karim Baghery and Helger Lipmaa and Janno Siim and Michal Zajac},
      title = {{UC}-Secure {CRS} Generation for {SNARKs}},
      howpublished = {Cryptology ePrint Archive, Paper 2019/471},
      year = {2019},
      note = {\url{}},
      url = {}
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