支持安全多方同态乘积计算的谓词加密方案

针对传统安全多方计算（SMC）加密方案中，每一位参与者都能获知最终结果，这种粗粒度的访问控制不适用于要求特定用户对密文进行解密的问题，提出了对计算结果解密权限控制更精确的加密方案。通过与谓词加密相结合，构造了一种支持安全多方同态乘积计算的谓词加密方案，具有乘法同态性。与现有的谓词加密方案相比，该方案不仅支持同态操作，并且在对最终计算结果的解密权限上，该方案的控制更加精确。在当前云环境背景下，实现了对计算结果访问控制细粒度更高的安全多方计算，并且验证方案达到不可区分的属性隐藏抵抗选择明文攻击（IND-AH-CPA）安全。

Predicate encryption scheme supporting secure multi-party homomorphic multiplicative computation

In the traditional Secure Multi-party Computation (SMC), each participant can obtain the final result, but this coarse-grained access control may not be suitable for the requirements of specific users to decrypt ciphertexts, thus a new encryption scheme which has more accurate access control on the decryption authority of computation results was put forward. Combined with predicate encryption, a predicate encryption scheme with multiplicative homomorphic property for the secure multi-party computation was constructed. Compared with the existing predicate encryption, it supports the homomorphic operation, and is more accurate in access control on the decryption authority of computation results. In the current background of cloud environment, the secure multi-party computation of more fine-grained access control on computation results is realized, which is proved secure under INDistinguishable Attribute-Hiding against Chosen Plaintext Attacks (IND-AH-CPA).