Week 8 Update 8.1

This week I continued implementing a Rust version of Poseidon. The entire permutation was completed in three commits shown below:

1. Added sbox function that computes the sbox stage. commit link.
2. Added linear_layer function. commit link
3. Added poseidon permutation. commit link

This implementation is based on the arkworks library and it uses the BLS12-381 curve. The parameters used for this instantiation are

• $\alpha =5$,
• $N=1275$ round constants,
• $n=255$ bits of security,
• $t=5$ width,
• $R_F=8$ number of full rounds,
• $R_P=60$ number of partial rounds,
• $p=$0x73eda753299d7d483339d80809a1d80553bda402fffe5bfeffffffff00000001.

The goal of the following week will be on implementing functionality for most of the elliptic curves instantiations of the arkworks library.