Attack test method and device

Abstract

The invention provides an attack test method and a device. The invention provides the attack test method aiming to solve chosen-plaintext attack of a key in an encryption algorithm of the prior art. The method comprises the following steps: receiving a plaintext; storing at least one part of the plaintext; judging whether the analogical number of the stored at least one part of the plaintext and other stored at least one part of the plaintext is more than or equal to a first threshold value; outputting a signal with an attack mode in the current plaintext if the analogical number is more than or equal to the first threshold value, otherwise, outputting a normal signal; and repeating the steps before the next plaintext comes. The method and the device have the advantages that the method and the device can test the inputting plaintext with obvious attack mode and avoid the chosen-plaintext attack on the key.

Description

technical field [0001] The invention relates to the field of security detection, in particular to the field of security detection of smart cards, and specifically relates to an attack detection method and device. Background technique [0002] In an encryption algorithm, a key is used to encrypt plaintext into ciphertext. Here, the term encryption algorithm is to be understood as an algorithm for calculating an identification code with respect to plaintext. Such an algorithm is also called a hash function with a key (cryptographic hash function). Here, the identification code of the plaintext is calculated from the plaintext using the key. In general, contrary to true encryption algorithms in the narrower sense, such functions cannot be reversed, ie decryption can no longer be performed. [0003] An encryption algorithm is used, for example, to authenticate a first instance against a second instance. To this end, for example, the first instance encrypts the plaintext it p...

AI Technical Summary

Problems solved by technology

However, when using this method, the SIM card may return an incorrect ciphertext, and re-authentication is required, so the network load increases and the error probability acceptable to the user will increase, and the attacker may directly use "3R-collision" which can be very effective implementation of cloning attacks

[0011] Chinese Patent Publication No. CN1941775, the title of the invention is "A Method and Device for Preventing Network Message Attacks". It is too large to be mistaken for attack data, resulting in misoperation, and this method is only used for network security detection, and has not been applied to the security field of smart cards such as SIM cards.

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