TY - GEN
T1 - Server-aided secure computation with off-line parties
AU - Baldimtsi, Foteini
AU - Papadopoulos, Dimitrios
AU - Papadopoulos, Stavros
AU - Scafuro, Alessandra
AU - Triandopoulos, Nikos
N1 - Publisher Copyright:
© 2017, Springer International Publishing AG.
PY - 2017
Y1 - 2017
N2 - Online social networks (OSNs) allow users to jointly compute on each other’s data (e.g., profiles, geo-locations, etc.). Privacy issues naturally arise in this setting due to the sensitive nature of the exchanged information. Ideally, nothing about a user’s data should be revealed to the OSN provider or non-friends, and even her friends should only learn the output of a specific computation. A natural approach for achieving these strong privacy guarantees is via secure multi-party computation (MPC). However, existing MPC-based approaches do not capture two key properties of OSN setting: Users does not need to be online while their friends query the OSN server on their data; and, once uploaded, user’s data can be repeatedly queried by the server on behalf of user’s friends. In this work, we present two concrete MPC constructions that achieve these properties. The first is an adaptation of garbled circuits that converts inputs under different keys to ones under the same key, and the second is based on 2-party mixed protocols and involves a novel 2-party re-encryption module. Using state- of-the-art cryptographic tools, we provide a proof-of-concept implementation of our schemes for two concrete use cases, overall validating their efficiency and efficacy in protecting privacy in OSNs.
AB - Online social networks (OSNs) allow users to jointly compute on each other’s data (e.g., profiles, geo-locations, etc.). Privacy issues naturally arise in this setting due to the sensitive nature of the exchanged information. Ideally, nothing about a user’s data should be revealed to the OSN provider or non-friends, and even her friends should only learn the output of a specific computation. A natural approach for achieving these strong privacy guarantees is via secure multi-party computation (MPC). However, existing MPC-based approaches do not capture two key properties of OSN setting: Users does not need to be online while their friends query the OSN server on their data; and, once uploaded, user’s data can be repeatedly queried by the server on behalf of user’s friends. In this work, we present two concrete MPC constructions that achieve these properties. The first is an adaptation of garbled circuits that converts inputs under different keys to ones under the same key, and the second is based on 2-party mixed protocols and involves a novel 2-party re-encryption module. Using state- of-the-art cryptographic tools, we provide a proof-of-concept implementation of our schemes for two concrete use cases, overall validating their efficiency and efficacy in protecting privacy in OSNs.
UR - http://www.scopus.com/inward/record.url?scp=85029498721&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85029498721&partnerID=8YFLogxK
U2 - 10.1007/978-3-319-66402-6_8
DO - 10.1007/978-3-319-66402-6_8
M3 - Conference contribution
AN - SCOPUS:85029498721
SN - 9783319664019
T3 - Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics)
SP - 103
EP - 123
BT - Computer Security – ESORICS 2017 - 22nd European Symposium on Research in Computer Security, Proceedings
A2 - Snekkenes, Einar
A2 - Foley, Simon N.
A2 - Gollmann, Dieter
T2 - 22nd European Symposium on Research in Computer Security, ESORICS 2017
Y2 - 11 September 2017 through 15 September 2017
ER -