中文摘要：

为满足云计算对高安全、高效率密码方案的需求,该文提出一种安全增强密码工作模式——密码反馈＂一组一密＂（Cipher FeedBack one Block one Key,CFB-BK）模式,并基于数学密码和光学密码组合实现：光学密码对数据分组进行＂一组一密＂加解密,数学密码利用光学密码密文生成供光学密码下一组数据加解密使用的密钥。安全性分析表明,攻击者在密码学技术范围内,只能采用穷举密钥攻击方式,攻击复杂度高;效率分析表明,比基于数学密码实现的模式效率更高。

英文摘要：

For meeting the high security and high efficiency of cryptography schemes in Cloud Computing, a security enhanced cryptographic mode of operation named Cipher FeedBack one Block one Key （CFB-BK） is proposed, and this mode is implemented based on the combination of mathematical cryptography and optical cryptography. Optical cryptography module encrypts （or decrypts） data blocks in a ＂one block one key＂ way. Moreover, it provides its ciphertext as a feedback to the mathematical cryptography module, which uses it to generate keys for the next block encryption （or decryption） of the optical cryptography module. Security analysis shows that the only possible attack in the area of cryptography for the proposed scheme is exhaustive attack, indicating that no adversary could get a significant advantage against the scheme without spending a huge amount of recourses and time. Efficiency analysis shows that the scheme implementing CFB-BK mode works much faster than the existing modes implemented based on mathematical cryptography.