Probabilistic symmetric encryption have already been widely studied, from a theoretical point of view. Nevertheless, many applications require length-preserving encryption, to be patched at a minimal cost to include privacy without modifying the format (e.g. encrypted filesystems). In this paper, we thus consider the security notions for length-preserving, deterministic and symmetric encryption...

In this work, we consider the problem of key cloning in attribute-based encryption schemes. We introduce a new type of attribute-based encryption scheme, called token-based attributebased encryption, that provides strong deterrence for key cloning, in the sense that delegation of keys reveals some personal information about the user. We formalize the security requirements for such a scheme in t...

Assume that a symmetric encryption scheme has been deployed and used with a secret key. We later must change the encryption scheme in a way that preserves the ability to decrypt (a subset of) previously encrypted plaintexts. Frequent real-world examples are migrating from a token-based encryption system for credit-card numbers to a format-preserving encryption (FPE) scheme, or extending the mes...

In this work, we study the problem of privacy preserving computation on PageRank algorithm. The idea is to enforce the secure multi party computation of the algorithm iteratively using homomorphic encryption based on Paillier scheme. In the proposed PageRank computation, a user encrypt its own graph data using asymmetric encryption method, sends the data set into different parties in a privacy-...

We present an efficient structure-preserving tagged one-time signature scheme with tight security reductions to the decision-linear assumption. Our scheme features short tags consisting of a single group element and gives rise to the currently most efficient structure-preserving signature scheme based on the decision-liner assumption with constant-size signatures of only 14 group elements, wher...

The challenge in privacy-preserving data mining is avoiding the invasion of personal data privacy. Secure computation provides a solution to this problem. With the development of this technique, fully homomorphic encryption has been realized after decades of research; this encryption enables the computing and obtaining results via encrypted data without accessing any plaintext or private key in...

It has become advantageous in certain scenarios for a database owner to outsource hosting and management of his database to a third party. This approach is known as database as a service or DAS. However, in the case of highly sensitive data, it may be necessary to protect it even from the third party database administrator. As a result, several methods have been proposed that allow for encrypti...

Structure-preserving cryptography is a world where messages, signatures, ciphertexts and public keys are entirely made of elements of a group over which a bilinear map is efficiently computable. While structure-preserving signatures have received much attention the last 6 years, structure-preserving encryption schemes have undergone slower development. In particular, the best known structure-pr...