Cryptography Stack Exchange
Cryptography Stack Exchange

Questions tagged [mixing-function]

The purpose of the mixing function is to "scramble" or mix the internal state of a hash (or cipher) function. The input to the function is the current internal state and the output of the function becomes the new internal state.

The purpose of the mixing function is to "scramble" or mix the internal state of a hash (or cipher) function. The input to the function is the current internal state and the output of the function becomes the new internal state.

The behavior of the mixing function largely determines whether (for example) a hash function is collision-resistant. The most notable difference between a mixing function and a hash function is that the input and output of a mixing function are the same size.

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AES column mixing and S-Box confusion

I am trying to understand the AES encryption algorithm. I know that we process 128 bits at a time for a 128 bit key in a 4x4 octet form, but am confused by the following: How does the substitution subround work, as the size of the Rijndael's S-box…
johnny
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How can bit slicing be constant time, when Mix Columns is in the cipher

I'm reading about bit-slicing techniques, and one thing about it caught my mind. The strength with bit sliced implementations are (apart from that they are fast) that they are running in constant time. This outrules side-channel attacks based on…
oPolo
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Need 32-bit mixing function that has perfect avalanche between octets

for my hobby tinkering project, I need a mixing function that takes 32-bit input and has 32-bit output (and will, most likely, run in a 32-bit C environment) and the following property (independent of endianness, i.e. it’s enough to only look at…
mirabilos
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Construct block cipher from a smaller one with mixing function

I read about the AEZ encryption scheme as presented at the CAESAR competition. To me it seems like a construction of an arbitrary length block cipher from a smaller one. The key component is the mixing function. (See the figure… Left: without cipher…
Curious Sam
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How unique and secure are verification codes created from different hashes?

In order to construct a short, yet cryptographically strong verification code, I'm thinking about using the output of several hashes computed over the same data (device uuids + raw certificate data). Pseudocode: char *data[] = [clientUUID +…
Felix Schwarz
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What happens if the column mixing in AES is replaced by simple XOR and subtraction?

This is https://github.com/kokke/tiny-AES-c The column mixing function in the AES algorithm implemented. static uint8_t xtime(uint8_t x) { return ((x << 1) ^ (((x >> 7) & 1) * 0x1b)); } // MixColumns function mixes the columns of the state…
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Is blinded mixing possible?

Alice creates ordered set of $N$ public messages $(m_1,...,m_N)$ and sequentially sends them to Bob. Bob evaluates $N$ functions $E_i(m_1,...,m_N)$ (possibly using a secret random value $r$ and/or his own private key $d_B$) and makes $N$ resulting…
DeLorean88
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RC4 via nonlinear mixer -- sound?

We implemented a rc4 (ARC4) variant for creating a cryptographic stream - question is: Is this sound? (I'll give an example for 32 bit variant, though 64 bit/larger is possible) Algorithm is as follows: We have an array of integers A (32 bit) and…
Zaphod1001
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