关于BEAR和LION方案的可证安全性
On the provable security of BEAR and LION schemes
摘要：
BEAR、LION和LIONESS是Biham和Anderson（1996）提出的分组密码，其灵感来自于著名的Luby-Rackoff构造（1988）。Biham和Anderson提出的密码是基于一个流密码和一个散列函数。基元的良好性质保证了分组密码的良好性质。特别是，他们能够证明他们的密码是免疫任何有效的已知明文密钥恢复攻击，可以使用作为输入只有一个明文密文对。我们的贡献表明，这些密码实际上是免疫任何有效的已知明文密钥恢复攻击，可以使用任何数量的明文密文对作为输入。我们能够通过对基元使用稍微弱一点的假设来获得这种改进。我们还讨论了Morin（1996）的攻击。
英文摘要：
BEAR, LION and LIONESS are block ciphers presented by Biham and Anderson (1996), inspired by the famous Luby-Rackoff constructions of block ciphers from other cryptographic primitives (1988). The ciphers proposed by Biham and Anderson are based on one stream cipher and one hash function. Good properties of the primitives ensure good properties of the block cipher. In particular, they are able to prove that their ciphers are immune to any efficient known-plaintext key-recovery attack that can use as input only one plaintext-ciphertext pair. Our contribution is showing that these ciphers are actually immune to any efficient known-plaintext key-recovery attack that can use as input any number of plaintext-ciphertext pairs. We are able to get this improvement by using slightly weaker hypotheses on the primitives. We also discuss the attack by Morin (1996).
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
