A General Analysis of the Security of Elastic Block Ciphers
نویسندگان
چکیده
We analyze the security of elastic block ciphers in general to show that an attack on an elastic version of block cipher implies a polynomial time related attack on the fixed-length version of the block cipher. We relate the security of the elastic version of a block cipher to the fixed-length version by forming a reduction between the versions. Our method is independent of the specific block cipher used. The results imply that if the fixed-length version of a block cipher is secure against attacks which attempt key recovery then the elastic version is also secure against such attacks.
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