Provably-Secure Cancelable Biometrics Using 2-DNF Evaluation

Abstract

Biometric authentication has been attracting much attention because it is more user-friendly than other authentication methods such as password-based and token-based authentications. However, it intrinsically comprises problems of privacy and revocability. To address these issues, new techniques called cancelable biometrics have been proposed and their properties have been analyzed extensively. Nevertheless, only a few considered provable security, and provably secure schemes known to date had to sacrifice user-friendliness because users have to carry tokens so that they can securely access their secret keys. In this paper, we propose two cancelable biometric protocols each of which is provably secure and requires no secret key access of users. We use as an underlying component the Boneh-Goh-Nissim cryptosystem proposed in TCC 2005 and the Okamoto-Takashima cryptosystem proposed in Pairing 2008 in order to evaluate 2-DNF (disjunctive normal form) predicate on encrypted feature vectors. We define a security model in a semi-honest manner and give a formal proof which shows that our protocols are secure in that model. The revocation process of our protocols can be seen as a new way of utilizing the veiled property of the underlying cryptosystems, which may be of independent interest.

A Spoofing Attack against a Cancelable Biometric Authentication Scheme

“…The construction of the rest of this paper is as follows: Section 2 explains cancelable authentication schemes by Hattori et al [4] and Hirano et al [5], [6], in addition to a homomorphic encryption scheme by Boneh-Goh-Nissim [2].…”

“…In this section, we explain a cancelable biometric authentication scheme by Hattori et al (called the fundamental scheme in this paper) [4], and two revised authentication schemes by Hirano et al [5], [6]. In these schemes, a homomorphic encryption scheme by Boneh, Goh, and Nissim (BGN scheme) [2], or by Okamoto, and Takashima (OT scheme) [9] is used.…”

“…1. A cancelable biometric authentication scheme by Hattori et al [4] the discrete logarithm value, is O √ S , the parameter S should be set so that this computation is feasible.…”

“…With the feature vectors, the template and the biometric information to compare can be compared with keeping encrypted. In fact, various cancelable authentication schemes with homomorphic encryption have been proposed [1], [11], [12], [4].…”

“…In 2012, Hattori et al proposed a cancelable authentication scheme based on homomorphic encryption schemes (which is called the fundamental scheme in this paper) [4]. There are three entities in this scheme: users, an authentication server (which stores user's encrypted templates and proceeds a comparison), and a decryption center (which judges the authentication result by decrypting the encrypted comparison result), where the templates and the biometric information to compare are always encrypted, and the comparison result also in encrypted.…”