不含双线性对的密文检索公钥加密方案

Ciphertext Search Public Key Encryption Scheme Without Bilinear Pairings

针对非可信云环境中的密文检索问题,在dPEKS模型的基础上,提出一种不含双线性对运算的密文检索公钥加密方案。该方案借鉴了RSA算法和Elgaml算法的思想,基于特殊模剩余类环上、循环群中的运算来构造加解密和检索子算法。在判定性Diffie-Hellman问题困难假设的前提下,证明了该方案可以抵抗不可区分性选择明文攻击和离线关键词猜测攻击。性能分析结果表明,该方案能够有效加解密数据,支持密文的关键词检索,并且在运算效率上比现有同等级安全的公钥加密方案更具优势。

In order to solve ciphertext search in untrusted cloud environment,this paper proposes a new ciphertextssearchable public key encryption scheme without bilinear pairings computation based on Searchable Public Key Encryption with a Designated Tester（dPEKS） scheme.The scheme references the thought of RSA algorithm and Elgaml algorithm,a special cyclic group is constructed from modulo-residue class ring.Based on this cyclic group,it constructs the encryption algorithm,decryption algorithm and keyword-search algorithm.This scheme satisfies indistinguishability against adaptive chosen plaintext attack and the off-line keywords-guessing attack,if the discrete logarithm assumption and decisional Diffie-Hellman assumption stand in the chosen cyclic group.Analysis results show that it can encrypt and decrypt data effectively,and search the cipher with keywords correctly.In addition,the scheme has obvious advantages of efficiency compared with schemes which have the same security.