Learning With Errors News Today

About two years ago, I switched teams at Google to focus on fully homomorphic encryption (abbreviated FHE, or sometimes HE). Since then I’ve got to work on a lot of interesting projects, learning along the way about post-quantum cryptography, compiler design, and the ins and outs of fully homomorphic encryption. If you’ve heard about FHE and you’re a software person, you’ve probably heard two things: it lets you run programs directly on encrypted data without ever decrypt...

When data security is facing growing threats, ordinary encryption techniques cannot meet the needs of comparing, sharing, and classifying data hidden in ciphertexts. At the same time, the advent of the quantum computing era has brought unprecedented challenges to traditional cryptography. Fortunately, a lattice-based PKEET scheme can solve the above problems. In this paper, we design a lattice-based PKE-DET scheme that can support the delegated tester function with satisfying anti-quantum comput...

In hospital information systems, large volumes of electronic diagnostic records (EDRs) take up most of the storage space. While cloud server providers can reduce the local storage burden on hospitals and provide data-sharing services, the potential threat of sensitive data leakage and non-traceability of diagnoses prevents hospitals from uploading patients' diagnostic records to remote cloud servers directly. Therefore, to address security and traceability issues, we propose a new construct...

Spatial encryption (SE), which involves encryption and decryption with affine/vector objects, was introduced by Boneh and Hamburg at Asiacrypt 2008. Since its introduction, SE has been shown as a versatile and elegant tool for implementing many other important primitives such as (Hierarchical) Identity-based Encryption ((H)IBE), Broadcast (H)IBE, Attribute-based Encryption, and Forward-secure cryptosystems. This paper revisits SE toward a more compact construction in the lattice setting. In doin...

Puncturable encryption (PE), introduced by Green and Miers at IEEE S&P 2015, allows recipients to update their decryption keys to revoke decryption capability for selected messages without communicating with senders. In general, it allows users to control which ciphertexts their keys may decrypt. The notion of PE has been found very useful in many applications, such as asynchronous messaging systems, group messaging systems, public-key watermarking schemes, secure cloud emails, and many more...

As cloud computing has developed rapidly, outsourcing data to cloud servers for remote storage has become an attractive trend. However, when cloud clients store their data in the cloud, the security and privacy of cloud data would be threatened due to accidental corruptions or purposive attacks caused by a semi-trusted cloud server. The widely used method of addressing the security and privacy of cloud data is to store encrypted data instead of plain data. As the resulting system is unusable, si...

With the rapid growth of cloud storage and cloud computing services, many organizations and users choose to store the data on a cloud server for saving costs. However, due to security concerns, data of users would be encrypted before sending to the cloud. However, this hinders a problem of computation on encrypted data in the cloud, especially in the case of performing data matching in various medical scenarios. Public key encryption with equality test (PKEET) is a powerful tool that allows the ...

The concept of puncturable encryption was introduced by Green and Miers at IEEE S&P 2015. Puncturable encryption allows recipients to update their decryption keys to revoke decryption capability for selected messages without communicating with senders. From the first instantiation, puncturable encryption shows its essence for many interesting applications, such as asynchronous messaging systems, group messaging systems, public-key watermarking schemes, secure cloud emails, and many more. To ...

Group encryption (GE) is a fundamental anonymity primitive analogue of group signature, which guarantees the decryption ability of recipients to specific ciphertexts while hiding these users within a crowd. Since its first birth by Kiayias et al., numerous constructions have been proposed, among which there is only one lattice-based scheme is post-quantum secure. However, the security of all these schemes will be damaged once an unexpected key-exposure attack occurs (which is extremely unavoidab...

Wildcard identity-based encryption (WIBE) is a generalization of hierarchical identity-based encryption (HIBE) where a sender can simultaneously encrypt messages to a group of users matching a certain pattern, defined as a sequence of identities and wildcards. This special feature makes WIBE a promising solution to distributed IoT data security. In this paper, we propose the first construction of a post-quantum WIBE scheme. Our scheme is proven secure in the standard model, and it enjoys the sec...