Ciphertext-Policy Attribute-Based Encrypted Data Equality Test and Classification

Abstract

Thanks to the ease of access and low expenses, it is now popular for people to store data in cloud servers. To protect sensitive data from being leaked to the outside, people usually encrypt the data in the cloud. However, management of these encrypted data becomes a challenging problem, e.g. data classification. Besides, how to selectively share data with other users is also an important and interesting problem in cloud storage. In this paper, we focus on ciphertext-policy attribute based encryption with equality test (CP-ABEET). People can use CP-ABEET to implement not only flexible authorization for the access to encrypted data, but also efficient data label classification, i.e. test of whether two encrypted data contain the same message. We construct an efficient CP-ABEET scheme, and prove its security based on a reasonable number-theoretic assumption. Compared with the only existing CP-ABEET scheme, our construction is more efficient in key generation, and has shorter attribute-related secret keys and better security.

Attribute-Based Equality Test Over Encrypted Data Without Random Oracles

“…To make the result more universal and credible, we independently set the test times as 500, 1000, 2000 and 4000. Figure 3(a), 3(b), 3(c), 3(d) show us that our CP-ABEET is more efficient than scheme in [10] in Test algorithm, and the efficiency of KeyGen, Enc and Dec algorithm is similar with that in [10]. As the number of tests increases, the running time increases linearly.…”

“…Later, Wang et al [9] proposed a construction of CP-ABEET scheme. Recently, Cui et al [10] proposed another CP-ABEET scheme, which enhances the security of [9]. Then, Cui et al [26] provided another CP-ABEET scheme, which supports to outsource the dominating computations of decryption and equality test to a third-party.…”

“…To better show the practical performance of our new CP-ABEET, we strictly simulated our scheme system and made a practical comparison with the last CP-ABEET [10] scheme which is proven secure in random oracle. We mainly used the Java Pairing-Based Cryptography (JPBC) library and the Bouncycastle library to realize our system.…”

“…Recently, Zhu et al [8] introduced the notion of Key-policy Attribute-based Encryption with Equality Test (KP-ABEET). Wang et al [9] and Cui et al [10] studied the ciphertext-policy counterpart and presented their constructions of Ciphertext-policy Attribute-based Encryption with Equality Test (CP-ABEET). Take CP-ABEET as an example, it embeds an access policy in the encryption of a message, so that only the authorized receiver whose attribute set satisfies the embedded policy could successfully decrypt and test the ciphertexts.…”

Lightweight Fine-Grained Access Control for Wireless Body Area Networks

“…Attribute-based encryption (ABE) [8,9] is a promising tool to afford confidentiality and fine-grained access control simultaneously. Generally, ABE schemes can be divided into three categories key-policy ABE (KP-ABE) [10], ciphertext-policy ABE (CP-ABE) [11], and dual-policy ABE (DP-ABE) [12]. In a KP-ABE, a data user's secret-key is associated with an access control policy which is defined by a central authority, and each ciphertext is labeled by a set of attributes.…”