Noble is a simple wrapper to make working with Go's implementation of Argon2 (specifically Argon2id) much easier. Argon2 is a modern ASIC-resistant and GPU-resistant secure key derivation function. It has better password cracking resistance (when configured correctly) than PBKDF2 , Bcrypt and Scrypt (for similar configuration parameters for CPU and RAM usage).

You would use this package when saving password hashes to a database for user authentication. While Go's bcrypt and scrypt packages are battle tested and popular, they are more vulnerable to password cracking, particularly with the advent of powerful GPU chips on modern systems.

Argon2 is a key derivation function that was selected as the winner of the 2015 Password Hashing Competition. It was designed by Alex Biryukov, Daniel Dinu, and Dmitry Khovratovich from the University of Luxembourg. There are three different versions of the algorithm, and according to OWASP, the Argon2id variant should be used, as it provides a balanced approach to resisting both side-channel and GPU-based attacks.

Install it in the usual way:

go get -u github.com/tsawler/noble

package main

import (
	"fmt"
	"github.com/tsawler/noble"
	"log"
)

func main() {
	// Create an instance of the type noble.Argon.
	n := noble.New()

	// Try creating a hash from a password. The returned value will 
	// include the hash, as well as all information need to validate a 
	// password against that hash using argon2.
	password := "verysecret"
	hash, err := n.GeneratePasswordKey(password)
	if err != nil {
		log.Println(err)
	}

	fmt.Println("hash for", password, "\n\t", hash)

	// Try comparing a valid password against this hash.
	valid, err := n.ComparePasswordAndKey(password, hash)
	fmt.Println("First password/hash compare is", valid)

	// Now compare with an invalid password.
	valid, err = n.ComparePasswordAndKey(password+"fish", hash)
	fmt.Println("Second password/hash compare is", valid)
}

The output of this program is:

(base) tcs@Grendel nobleapp % go run .
hash for verysecret 
         $argon2id$v=19$m=61440,t=1,p=4$XjQXPOyUmwUJAFPgNSMi+w$ZhBXt6gtrBnNyrFQ+i0ZlTbLS6WWrK8WKRmVQtXbY/Y
First password/hash compare is true
Second password/hash compare is false