Noir Array Helpers

Noir Array Helpers is a Noir function library to manipulate arrays. This library serves a kitchen sink for various array functions the Noir community finds useful.

WARNING!

| It is not recommended to use versions of this library < v0.30.0

This library was related to a vulnerability in ecrecover found by @olehmisar. Vulnerability details can be found here.

Installation

In your Nargo.toml file, add the following dependency:

[dependencies]
array_helpers = { tag = "v0.30.0", git = "https://github.com/colinnielsen/noir-array-helpers" }

then use it in your circuits:

use dep::std;
use dep::array_helpers;

fn main(){
    let pub_key: [u8; 64] = [...];

    let (pub_key_x, pub_key_y) = split_u8_64(pub_key);
    std::println(pub_key_x);
    std::println(pub_key_y);
}

or

use dep::std;
use dep::array_helpers::split_u8_64;

fn main(){
let eth_addr_u8: [u8;20] = [...];

    let addr = array_helpers::u8_to_eth_address(pub_key_x, pub_key_y);
    std::println(addr);

}

Usage

Here are the methods available in the library:

split_u8_64

Splits an array of u8 values, with a length of 64, into two arrays of u8 values, each with a length of 32.

fn split_u8_64(arr: [u8; 64]) -> ([u8; 32], [u8; 32])

u8_32_to_u8_64

Combines two arrays of u8 values, each of length 32, into a single array of u8 values, with a length of 64.

fn u8_32_to_u8_64(arr_a: [u8; 32], arr_b: [u8; 32]) -> [u8; 64]

u8_to_u160

Converts an array of u8 values to a Field value, representing a u160 value.

NOTE: These are also aliased to u8_to_eth_address, for readability.

fn u8_to_u160(array: [u8]) -> Field

fn u8_to_eth_address(array: [u8]) -> Field

u8_32s_to_u64_16

Converts two arrays of u8 values, each of length 32, to a single array of u64 values, with a length of 16.

fn u8_32s_to_u64_16(arr_a: [u8; 32], arr_b: [u8; 32]) -> [u64; 16]

u64_4_to_u8_32

Converts an array of u64 values, with a length of 4, to an array of u8 values, with a length of 32.

fn u64_4_to_u8_32(array: [u64; 4]) -> [u8; 32]

License

This project is licensed under the MIT License. See the LICENSE file for details.