Abstract: In stream cipher algorithm LEX under ECRYPT project, every encryption of AES uses the same key. This leads it to be attacked by slide attack easily. This paper improves the key selection of stream cipher algorithm LEX by using AES key extension algorithm. The improved LEX algorithm can resist slide attack effectively.

Key words: ECRYPT project, stream cipher, LEX algorithm, slide attack

摘要： ECRYPT项目中的流密码LEX算法中每组AES加密过程使用相同的加密密钥，这导致其易受到滑动攻击。利用AES的密钥扩展算法改进了流密码LEX算法的密钥采用方案，改进后算法能够有效地抵抗滑动攻击。

关键词: ECRYPT项目, 流密码, LEX算法, 滑动攻击