Schnorr-based implicit certification: improving the security and efficiency of V2X communications

Paulo S.  L.  M.  Barreto; Marcos A.  Simplicio Jr.; Jefferson E.  Ricardini; Harsh Kupwade Patil

Paper 2019/157

Schnorr-based implicit certification: improving the security and efficiency of V2X communications

Paulo S. L. M. Barreto, Marcos A. Simplicio Jr., Jefferson E. Ricardini, and Harsh Kupwade Patil

Abstract

In the implicit certification model, the process of verifying the validity of the signer's public key is combined with the verification of the signature itself. When compared to traditional, explicit certificates, the main advantage of the implicit approach lies in the shorter public key validation data. This property is particularly important in resource-constrained scenarios where public key validation is performed very often, which is common in vehicular communications (V2X) that employ pseudonym certificates. In this article, we show that an alternative, Schnorr-based implicit certification procedure can improve the efficiency of a popular V2X-oriented pseudonym certificate provisioning approach, the (unified) butterfly key expansion. As an additional contribution, we show that butterfly keys are vulnerable to existential forgery attacks under certain conditions, and also discuss how this issue can be fixed in an effective and efficient manner.

Note: We would also like to thank Zhaohui Cheng and Paul Bottinelli for their useful comments on an early version of this manuscript.

Metadata

Available format(s): PDF
Category: Cryptographic protocols
Publication info: Published elsewhere. Minor revision. IEEE Transactions on Computers.
DOI: 10.1109/TC.2020.2988637
Keywords: Vehicular communications (V2X)implicit certificates butterfly key expansion security
Contact author(s): joliveira @ larc usp br
History: 2020-04-22: last of 3 revisions; 2019-02-20: received; See all versions
Short URL: https://ia.cr/2019/157
License: CC BY

BibTeX

@misc{cryptoeprint:2019/157,
      author = {Paulo S.  L.  M.  Barreto and Marcos A.  Simplicio Jr. and Jefferson E.  Ricardini and Harsh Kupwade Patil},
      title = {Schnorr-based implicit certification: improving the security and efficiency of {V2X} communications},
      howpublished = {Cryptology {ePrint} Archive, Paper 2019/157},
      year = {2019},
      doi = {10.1109/TC.2020.2988637},
      url = {https://eprint.iacr.org/2019/157}
}