Keccak or SHA-3

Keccak is a hash function based on interesting and novel ideas. Some Keccak sponge-hash-function pointers:

A sponge function is a generalization of both hash functions, which have a fixed output length, and stream ciphers (=state cipher), which have a fixed input length.

Random sponge = Random permutation

“The sponge construction:

First, the input string is padded with a reversible padding rule and cut into blocks of r bits. Then the b bits of the state are initialized to zero and the sponge construction proceeds in two phases:

  • In the absorbing phase, the r-bit input blocks are XORed into the first r bits of the state, interleaved with applications of the function f, a fixed length permutation/transformation function function. When all input blocks are processed, the sponge construction switches to the squeezing phase.
  • In the squeezing phase, the first r bits of the state are returned as output blocks, interleaved with applications of the function f. The number of output blocks is chosen at will by the user.

The last c bits of the state are never directly affected by the input blocks and are never output during the squeezing phase.”

https://keccak.team/keccak_specs_summary.html

https://stackoverflow.com/questions/45158351/sha-3-in-python-implementation

https://stackoverflow.com/questions/43063282/qcryptographichash-what-is-sha3-here-in-reality

 

Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

w

Connecting to %s