Attribute-Based Authentication in Secure Group Messaging for Distributed Environments

Autor:	Soler, David, Dafonte, Carlos, Fernández-Veiga, Manuel, Vilas, Ana Fernández, Nóvoa, Francisco J.
Rok vydání:	2024
Předmět:	Computer Science - Cryptography and Security
Druh dokumentu:	Working Paper
Popis:	Messaging Layer security (MLS) and its underlying Continuous Group Key Agreement (CGKA) protocol allows a group of users to share a cryptographic secret in a dynamic manner, such that the secret is modified in member insertions and deletions. Although this flexibility makes MLS ideal for implementations in distributed environments, a number of issues need to be overcome. Particularly, the use of digital certificates for authentication in a group goes against the group members' privacy. In this work we provide an alternative method of authentication in which the solicitors, instead of revealing their identity, only need to prove possession of certain attributes, dynamically defined by the group, to become a member. Instead of digital certificates, we employ Attribute-Based Credentials accompanied with Selective Disclosure in order to reveal the minimum required amount of information and to prevent attackers from linking the activity of a user through multiple groups. We formally define a CGKA variant named Attribute-Authenticated Continuous Group Key Agreement (AA-CGKA) and provide security proofs for its properties of Requirement Integrity, Unforgeability and Unlinkability. We also provide guidelines for an integration of our construction in MLS. Comment: Submitted to IEEE Transactions on Dependable and Secure Computing This work has been submitted to the IEEE for possible publication. Copyright may be transferred without notice, after which this version may no longer be accessible
Databáze:	arXiv
Externí odkaz:	http://arxiv.org/abs/2405.12042 Zobrazit plný text záznamu View this record from Arxiv