中文摘要：

为了促使计算能力薄弱的云租户有效及公平地重构秘密,结合云外包计算和秘密共享特性,提出一种云外包秘密共享方案。在云外包秘密共享过程中,云租户间无需交互,只需进行少量解密和验证操作,而将复杂耗时的秘密重构计算外包给云服务提供商。该方案无需复杂的交互论证或零知识证明,能够及时发现云租户和云服务提供商的恶意行为,达到抵抗隐蔽敌手攻击的目的,最终每位云租户都能够公平和正确地得到秘密。安全分析和性能比较表明方案是安全和有效的。

英文摘要：

In order to make computationally weak cloud tenants can reconstruct a secret with efficiency and fairness, a cloud outsourcing secret sharing scheme was proposed, which combined cloud outsourcing computation with secret sharing scheme. In the process of outsourcing secret sharing, cloud tenants just need a small amount of decryption and validation operations, while outsource expensive cryptographic operations to cloud service provider （CSP）. The scheme, without complex interactive augment or zero-knowledge proof, could detect malicious behaviors of cloud tenants or cloud service providers. And the scheme was secure against covert adversaries. Finally, every cloud tenant was able to obtain the secret fairly and correctly. Security analysis and performance comparison show that scheme is safe and effective.