PAPR : Publicly Auditable Privacy Revocation for Anonymous Credentials
Brorsson, Joakim LU
; David, Bernardo
; Gentile, Lorenzo
; Pagnin, Elena
LU
and Wagner, Paul Stankovski
LU
(2023)
Cryptographers’ Track at the RSA Conference, CT-RSA 2023
In Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics)
13871 LNCS.
p.163-190
- Abstract
We study the notion of anonymous credentials with Publicly Auditable Privacy Revocation (PAPR). PAPR credentials simultaneously provide conditional user privacy and auditable privacy revocation. The first property implies that users keep their identity private when authenticating unless and until an appointed authority requests to revoke this privacy, retroactively. The second property enforces that auditors can verify whether or not this authority has revoked privacy from an issued credential (i.e. learned the identity of the user who owns that credential), holding the authority accountable. In other words, the second property enriches conditionally anonymous credential systems with transparency by design, effectively discouraging such... (More)
We study the notion of anonymous credentials with Publicly Auditable Privacy Revocation (PAPR). PAPR credentials simultaneously provide conditional user privacy and auditable privacy revocation. The first property implies that users keep their identity private when authenticating unless and until an appointed authority requests to revoke this privacy, retroactively. The second property enforces that auditors can verify whether or not this authority has revoked privacy from an issued credential (i.e. learned the identity of the user who owns that credential), holding the authority accountable. In other words, the second property enriches conditionally anonymous credential systems with transparency by design, effectively discouraging such systems from being used for mass surveillance. In this work, we introduce the notion of a PAPR anonymous credential scheme, formalize it as an ideal functionality, and present constructions that are provably secure under standard assumptions in the Universal Composability framework. The core tool in our PAPR construction is a mechanism for randomly selecting an anonymous committee which users secret share their identity information towards, while hiding the identities of the committee members from the authority. As a consequence, in order to initiate the revocation process for a given credential, the authority is forced to post a request on a public bulletin board used as a broadcast channel to contact the anonymous committee that holds the keys needed to decrypt the identity connected to the credential. This mechanism makes the user de-anonymization publicly auditable.
(Less)
- author
- Brorsson, Joakim
LU
; David, Bernardo
; Gentile, Lorenzo
; Pagnin, Elena
LU
and Wagner, Paul Stankovski
LU
- organization
- publishing date
- 2023
- type
- Chapter in Book/Report/Conference proceeding
- publication status
- published
- subject
- host publication
- Topics in Cryptology – CT-RSA 2023 - Cryptographers’ Track at the RSA Conference 2023, Proceedings
- series title
- Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics)
- editor
- Rosulek, Mike
- volume
- 13871 LNCS
- pages
- 28 pages
- publisher
- Springer Science and Business Media B.V.
- conference name
- Cryptographers’ Track at the RSA Conference, CT-RSA 2023
- conference location
- San Francisco, United States
- conference dates
- 2023-04-24 - 2023-04-27
- external identifiers
-
- scopus:85161390418
- ISSN
- 1611-3349
- 0302-9743
- ISBN
- 9783031308710
- DOI
- 10.1007/978-3-031-30872-7_7
- language
- English
- LU publication?
- yes
- id
- 14967cac-620a-4fb5-880a-1c71318d02dd
- date added to LUP
- 2023-09-15 14:29:52
- date last changed
- 2024-04-19 00:59:29
@inproceedings{14967cac-620a-4fb5-880a-1c71318d02dd,
abstract = {{<p>We study the notion of anonymous credentials with Publicly Auditable Privacy Revocation (PAPR). PAPR credentials simultaneously provide conditional user privacy and auditable privacy revocation. The first property implies that users keep their identity private when authenticating unless and until an appointed authority requests to revoke this privacy, retroactively. The second property enforces that auditors can verify whether or not this authority has revoked privacy from an issued credential (i.e. learned the identity of the user who owns that credential), holding the authority accountable. In other words, the second property enriches conditionally anonymous credential systems with transparency by design, effectively discouraging such systems from being used for mass surveillance. In this work, we introduce the notion of a PAPR anonymous credential scheme, formalize it as an ideal functionality, and present constructions that are provably secure under standard assumptions in the Universal Composability framework. The core tool in our PAPR construction is a mechanism for randomly selecting an anonymous committee which users secret share their identity information towards, while hiding the identities of the committee members from the authority. As a consequence, in order to initiate the revocation process for a given credential, the authority is forced to post a request on a public bulletin board used as a broadcast channel to contact the anonymous committee that holds the keys needed to decrypt the identity connected to the credential. This mechanism makes the user de-anonymization publicly auditable.</p>}},
author = {{Brorsson, Joakim and David, Bernardo and Gentile, Lorenzo and Pagnin, Elena and Wagner, Paul Stankovski}},
booktitle = {{Topics in Cryptology – CT-RSA 2023 - Cryptographers’ Track at the RSA Conference 2023, Proceedings}},
editor = {{Rosulek, Mike}},
isbn = {{9783031308710}},
issn = {{1611-3349}},
language = {{eng}},
pages = {{163--190}},
publisher = {{Springer Science and Business Media B.V.}},
series = {{Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics)}},
title = {{PAPR : Publicly Auditable Privacy Revocation for Anonymous Credentials}},
url = {{http://dx.doi.org/10.1007/978-3-031-30872-7_7}},
doi = {{10.1007/978-3-031-30872-7_7}},
volume = {{13871 LNCS}},
year = {{2023}},
}