带陷门分组密码算法的设计与分析

Design and analysis of trapdoor block cipher

带陷门的密码算法包含了陷门信息,知道陷门信息可以较容易地获得密码算法的密钥进而解密密文得到明文,对于不知道陷门信息的攻击者则无法有效获得密钥,并且要找到陷门信息在计算上也是很困难的。基于对称密码算法中带陷门信息的混淆部件设计了一种带陷门的分组密码算法,并对该算法进行了安全性分析,证明了在假设陷门信息保密(不公开)的情况下该类算法能够抵抗线性密码分析等攻击方法。基于这样的分组密码算法,讨论了构造公钥加密算法的思路。

The cryptographic algorithm with trapdoors contains trapdoor information.It is easy to obtain the cryptographic algorithm key and decrypt the ciphertext to obtain the plaintext,when trapdoor information is known.it is hard for attackers to obtain the key effectively,and finding trapdoor information,when trapdoor information is unknown.A block cipher with trapdoor is designed based on the confusing component with trapdoor information in symmetric cryptographic algorithm,and the security analysis of the algorithm is carried out,which proves that the algorithms are resistant to attack methods such as linear cryptanalysis,when the trapdoor information is in secret(not public).The paper discusses the idea of constructing public key cryptography algorithm based on such block cipher algorithm.