A cryptographic algorithm identification method and system based on ciphertext only

Abstract

The invention relates to the technical field of cipher algorithm identification, and discloses a cipher algorithm identification method based on only-ciphertext. The cipher algorithm identification method concretely comprises that step 1: cipher algorithms needing to be identified are determined, and then ciphertext files are generated corresponding to the cipher algorithms needing to be identified; step 2: ciphertext data characteristics of the generated ciphertext files are extracted, and key characteristics are screened out; step 3: the key characteristics serve as a characteristic matching database of a cipher algorithm identification model, an identification algorithm in machine learning is combined, and a preliminary identification model is established; step 4: some ciphertext files are regenerated corresponding to the cipher algorithms, key characteristics of the new ciphertexts are obtained in the same way, and then serve as the input of an identification model, and preliminary identification is carried out to the cipher algorithms; and step 5: after multi-time optimization processes, a stable identification model is finally obtained, and is directly used for cipher algorithm identification based on only-ciphertext information.

Description

Technical field [0001] The invention relates to the technical field of cryptographic algorithm identification, in particular to a cryptographic algorithm identification method and system based on cipher text. Background technique [0002] Information confidential communication, secure storage, integrity protection, authentication, signature and verification, etc. are inseparable from the use of cryptographic algorithms. Cryptographic algorithms are the core of information security technology. The security of cryptographic algorithms plays an inestimable role. Kerckhoffs' basic hypothesis for cryptanalysis explained all the details of cryptographic algorithms known to cryptanalysts and their implementation. Almost all existing cryptanalysis techniques are based on known algorithms. However, in the analysis of public opinion, the only information we obtain is ciphertext, which is unknown to the cryptanalyst. But one thing can be confirmed, users are basically not professional cryp...

AI Technical Summary

Problems solved by technology

[0008] (1) Only some exploratory theoretical research has been done. Many experimental ciphertext data do not conform to the actual situation. For example, all ciphertexts in the experiment correspond to the same key, and there is no strict limit on the size of the ciphertext file used in the test.

[0009] (2) The identified cryptographic algorithm does not specify the algorithm parameters, but only identifies the cryptographic algorithm by the algorithm name

[0010] (3) Basically, only a few block cipher algorithms are identified, and no other valuable research content has been found to expand

Images