Biblio
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An Efficient Cryptography-Based Access Control Using Inner-Product Proxy Re-Encryption Scheme. Proceedings of the 13th International Conference on Availability, Reliability and Security. :12:1–12:10.
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2018. Inner-product encryption (IPE) is a well-known functional encryption primitive that allows decryption when the inner-product of the attribute vectors, upon which the encrypted data and the decryption key depend, is equal to zero. Using IPE, it is possible to define fine-grained access policies over encrypted data whose enforcement can be outsourced to the cloud where the data are stored. However, current IPE schemes do not support efficient access policy changes. In this paper, we propose an efficient inner-product proxy re-encryption (E-IPPRE) scheme that provides the proxy server with a transformation key, with which a ciphertext associated with an attribute vector can be transformed to a new ciphertext associated with a different attribute vector, providing a policy update mechanism with a performance suitable for many practical applications. We experimentally assess the efficiency of our protocol and show that it is selective attribute-secure against chosen-plaintext attacks in the standard model under the Asymmetric Decisional Bilinear Diffie-Hellman assumption.
Efficient Implementation of a Proxy-based Protocol for Data Sharing on the Cloud. Proceedings of the Fifth ACM International Workshop on Security in Cloud Computing. :67–74.
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2017. In this paper, we provide a secure and efficient outsourcing scheme for multi-owner data sharing on the cloud. More in detail we consider the scenario where multiple data owners outsource their data to an untrusted cloud provider, and allow authorized users to query the resulting database, composed of the encrypted data contributed by the different owners. The scheme relies on a proxy re-encryption technique that is implemented using an El-Gamal Elliptic Curve(ECC) crypto-system. We experimentally assess the efficiency of the implementation in terms of computation time, including the key translation process, data encryption and re-encryption modules, and show that it improves over previous proposals.