Linear cryptanalysis is a known plaintext attack and uses a linear approximation to describe the behavior of the block cipher. Given sufficient pairs of plaintext and corresponding ciphertext, bits of information about the key can be obtained and increased amounts of data will usually give a higher ...

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Linear cryptanalysis complete key guessing

In linear crypt analysis, partial sub keys are guessed and verified for its correctness with the help of plaintext and ciphertext. From the partial sub key, how it is possible to guess the complete ...
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How to calculate the non-linearity of an s-box?

I am struggling to understand how to calculate non-linearty of an s-box, could someone show me a detailed example? I found “How to calculate non linearity of AES S-box?” which helped a little, but I ...
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How to apply linear cryptanalysis to PRESENT?

Can someone help me implement linear cryptanalysis of the PRESENT block cipher? How should I start with 64 bits of plaintext and 80 bits of key?
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Matsui's Linear attack on DES P box

I'm trying to understand Matsui's linear attack on DES and I have something I don't understand in his paper. In his paper he say that: $NS_{5}(16,15)=12$ (which is OK) and from that he say that: ...
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The sign of the correlation in linear approximation

${\text{Let }}g:{\{ 0,1\} ^n} \to {\{ 0,1\} ^n}$ be a round function of an $n$-bit iterated block cipher and let $K \in {\{ 0,1\} ^n}$ be a fixed round-key, and denote ${g_K}(x) = g(x \oplus K).$ ...
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How does non-linearity (S-box) add security to AES?

I'm trying to understand how AES guarentees security. One of the named points on the web is that AES uses a non-linear step (the SubBytes step). But how exactly does the Rijndael key schedule add ...