delay_function.rs

#!/usr/bin/env rust-script

//! ```cargo
//! [dependencies]
//! argon2 = "0.5.3"
//! hex = "0.4.3"
//! ```

use argon2::{
    password_hash::{PasswordHasher, Salt},
    Algorithm, Argon2, Params,
};

const SALT: &str = "T1JBT19ORVRXT1JL";
const M_COST: u32 = 16 * 1024 * 1024;
const T_COST: u32 = 2048;
const P_COST: u32 = 1;
const OUTPUT_SIZE: Option<usize> = Some(32);

fn main() {
    let args: Vec<String> = std::env::args().collect();

    if args.len() != 2 {
        eprintln!("Expected args: {} <beacon input>", args[0]);
        std::process::exit(1);
    }

    let mut hash = [0_u8; 32];

    let beacon_input = hex::decode(&args[1]).expect("beacon input must be 32 byte hex");

    hash.copy_from_slice(
        beacon_input
            .get(..32)
            .expect("beacon input must be 32 byte hex"),
    );

    let argon2 = Argon2::new(
        Algorithm::Argon2d,
        Default::default(),
        Params::new(M_COST, T_COST, P_COST, OUTPUT_SIZE).unwrap(),
    );

    let salt = Salt::from_b64(SALT).unwrap();

    let result = argon2.hash_password(&hash[..], salt).unwrap().hash.unwrap();
    hash.copy_from_slice(result.as_bytes());

    println!("{}", hex::encode(hash));
}