Abstract. When data is outsourced to a remote storage server, search-able encryption plays an important role to protect data privacy while allowing users to retrieve data in the massive ciphertext. As far as we know, most of the existing searchable encryption schemes work based on the bilinear map. These schemes may not be secure in the quantum age. Both discrete logarithms and factorization can be solved by quantum computer in a polynomial time. There is very few searchable encryption scheme that can be proved secure in post quantum age. In this paper, in order to construct a post-quantum secure scheme for future cloud stor-age, we suggest a public key encryption with semantic keyword search using the lattice based mechanism. The suggested scheme is proved se-cure against indistinguishable chosen-keyword attacks (IND-CKA) based on learning with errors (LWE) problem. This scheme is believed to be secure in quantum-era due to the quantum intractability of the LWE problem.
Abstract. When data is outsourced to a remote storage server, search-able encryption plays an important role to protect data privacy while allowing users to retrieve data in the massive ciphertext. As far as we know, most of the existing searchable encryption schemes work based on the bilinear map. These schemes may not be secure in the quantum age. Both discrete logarithms and factorization can be solved by quantum computer in a polynomial time. There is very few searchable encryption scheme that can be proved secure in post quantum age. In this paper, in order to construct a post-quantum secure scheme for future cloud stor-age, we suggest a public key encryption with semantic keyword search using the lattice based mechanism. The suggested scheme is proved se-cure against indistinguishable chosen-keyword attacks (IND-CKA) based on learning with errors (LWE) problem. This scheme is believed to be secure in quantum-era due to the quantum intractability of the LWE problem.
Searchable encryption enables efficient retrieval of encrypted data stored in cloud environments while preserving data confidentiality. Within this context, Public Key Encryption with Keyword Search (PEKS) allows data users to perform keyword-based searches using their public-private key pairs. However, traditional PEKS schemes remain vulnerable to Inside Keyword Guessing Attacks (IKGA), which led to the introduction of the Public-Key Authenticated Encryption with Keyword Search (PAEKS) paradigm to enhance resilience against insider threats. Despite this advancement, most existing PAEKS schemes rely on number-theoretic assumptions, such as the discrete logarithm problem, thereby becoming insecure in the presence of against quantum adversaries. Consequently, recent research has focused on developing quantum-resistant, lattice-based PAEKS schemes. Although schemes based on the Learning with Errors (LWE) problem provide strong post-quantum security, they often incur high computational and communication costs, limiting their practicality in large-scale cloud environments. To overcome these limitations, this work presents an efficient and verifiable PAEKS scheme based on the Middle-Product LWE (MP-LWE) problem, which preserves the underlying security guarantees while significantly improving performance. Formal security analysis demonstrates resistance against Chosen Keyword Attack (CKA) and IKGA in the random oracle (RO) model. Experimental results confirm that the proposed scheme achieves substantially lower computational and communication overheads compared to existing schemes, while maintaining robust post-quantum security.
With the improvement of awareness of data privacy, the user's sensitive data are usually encrypted before uploading them to cloud. Searchable encryption is a critical technique on promoting secure and efficient cloud storage. In particular, publickey encryption with keyword search (PEKS) provides an elegant approach to achieve data retrieval in encrypted storage. All existing searchable publickey encryption schemes only provide the security based on classical cryptography hardness assumption. With the development of quantum computers, these schemes will be insecure. Based on the lattice hardness assumptions, we propose a new searchable publickey encryption scheme with a designated tester (dPEKS). Our scheme has advantages: First, our scheme is the first searchable publickey encryption scheme that is considered to be secure even if quantum computers are ever developed. Second, our scheme achieves the trapdoor indistinguishability. The trapdoor indistinguishability implies the security against outside offline keyword guessing attacks (KGAs). Last, our scheme can achieve the trapdoor anonymity for server.
With the improvement of awareness of data privacy, the user's sensitive data are usually encrypted before uploading them to cloud. Searchable encryption is a critical technique on promoting secure and efficient cloud storage. In particular, publickey encryption with keyword search (PEKS) provides an elegant approach to achieve data retrieval in encrypted storage. All existing searchable publickey encryption schemes only provide the security based on classical cryptography hardness assumption. With the development of quantum computers, these schemes will be insecure. Based on the lattice hardness assumptions, we propose a new searchable publickey encryption scheme with a designated tester (dPEKS). Our scheme has advantages: First, our scheme is the first searchable publickey encryption scheme that is considered to be secure even if quantum computers are ever developed. Second, our scheme achieves the trapdoor indistinguishability. The trapdoor indistinguishability implies the security against outside offline keyword guessing attacks (KGAs). Last, our scheme can achieve the trapdoor anonymity for server.
With the growing need for secure cloud storage and the threat of quantum attacks, we propose a post-quantum secure lattice-based multi-authority attribute-based multi-keyword searchable encryption scheme with dynamic membership. Based on the decisional learning with errors assumption, the proposed scheme resists quantum adversaries while supporting flexible multi-keyword search, decentralized authority to avoid key escrow, and dynamic attribute updates without affecting other users. It enables users to independently generate search tokens, allowing offline authorities and reducing communication overhead. Despite higher encryption costs, experimental results demonstrate that search and decryption remain efficient compared to existing post-quantum lattice-based solutions. The proposed scheme achieves strong data confidentiality and keyword privacy in the post-quantum setting.
To protect the privacy of cloud data, encryption before uploading provides a solution. However, searching for target data in ciphertext takes effort. Therefore, searchable encryption has become an important research topic. On the other hand, since the advancement of quantum computers will lead to the crisis of cracking traditional encryption algorithms, it is necessary to design encryption schemes that can resist quantum attacks. Therefore, we propose a multi-keyword searchable identity-based proxy re-encryption scheme from lattices. In addition to resisting quantum attacks, the proposed scheme uses several cryptographic techniques to improve encryption efficiency. First, identity-based encryption is used to reduce the computation and transmission costs caused by certificates. Second, the proposed scheme uses proxy re-encryption to achieve the purpose of outsourced computing, allowing the proxy server to reduce the computation and transmission costs of the users. Third, the proposed multi-keyword searchable encryption can provide AND and OR operators to increase the flexibility of searchability. Moreover, the access structure of the proposed scheme is not based on a linear secret sharing scheme (LSSS), avoiding the errors caused by an LSSS-based structure in decryption or search results. Finally, we also give formal security proof of the proposed scheme under the decisional learning with errors assumption.
Recently, how to retrieve the encrypted data efficiently from a cloud storage system becomes a hot topic. Public key encryption with keyword search (PEKS) can allow one to search the encrypted data with a keyword efficiently. Due to the booming of post-quantum cryptography, we propose public key encryption with keyword search from lattice assumption, which can resist quantum computer attacks. We delegate a particular cloud server to search the results, thus only the designated cloud server can finish the test process. Our scheme has been proved ciphertext indistinguishability in the standard model, which can reflect its security in the real world. To the best of our knowledge, our scheme is the first construction based on lattice in the standard model, which is a step stone in the post-quantum cryptographic communication.