Decide which library will be used for BLS bilinear pairings

[poulok]

Based on which elliptic curve @rsinha decides we should use, determine the library that needs to be wrapped and used by the Cryptography Module.

@AlfredoG87 needs to verify that the selection will work for smart contracts.

[rsinha]

Given the precompiles that are available, we can go with the BN254 curve. The interface for pairings is generic, so we can later swap this for a different curve as well, giving us crypto agility.

Some of the popular libraries implementing this curve are listed here: https://hackmd.io/@gnark/eccbench
Choosing arkworks crate (https://docs.rs/ark-bn254/latest/ark_bn254/) allows for supporting a large number of curves with the same generic interface, allowing for crypto agility.

[AlfredoG87]

@timo0 @rsinha

EVM chains will not support natively BN254 curve, the only one that is supported natively is alt_bn128 other curves might be supported using custom math, however Gas costs will make them undesirable to be used.

This are the available precompiles for EVM:

https://www.evm.codes/precompiled

[rsinha]

Ah, BN254 is the other name for alt_bn128. All good here :)