Module gf256 

gf256 is a module for field elements over the field GF(2**8) with irreducible polynomial x^8+x^4+x^3+x+1

WARNING this library was not audited by an expert in this area and does not guarantee constant-time cryptographic implmentation But, This module uses the Rust crate subtle to move towards this goal and one day hopes to acheive these guarantees

Examples

All elements are their own additive inverse GF256::zero() is the additive identity

use libss::gf256::GF256;
use libss::Field;

let x = GF256(80);
let x_plus_x = x + x;

assert_eq!(x_plus_x, GF256::zero());

All elements except zero have inverses

use libss::gf256::GF256;
use libss::Field;

let x = GF256(80);
let x_mul_x = x.inverse().unwrap() * x;

assert_eq!(x_mul_x, GF256::one());

Structs

GF256

Represents an element in the field GF(2**8) without the use of lookup tables. This module uses subtle to hopefully achieve constant time guarantees, however this code has not been audited and should not be used in production.