Class SCryptUtil

java.lang.Object

com.lambdaworks.crypto.SCryptUtil

public class SCryptUtil
extends Object

Simple SCrypt interface for hashing passwords using the scrypt key derivation function and comparing a plain text password to a hashed one. The hashed output is an extended implementation of the Modular Crypt Format that also includes the scrypt algorithm parameters. Format: $s0$PARAMS$SALT$KEY.

PARAMS

32-bit hex integer containing log2(N) (16 bits), r (8 bits), and p (8 bits)

SALT

base64-encoded salt

KEY

base64-encoded derived key

s0 identifies version 0 of the scrypt format, using a 128-bit salt and 256-bit derived key.

Constructor Summary

Constructors

Constructor	Description
SCryptUtil()

Method Summary

Modifier and Type	Method	Description
static boolean	check(String passwd, String hashed)	Compare the supplied plaintext password to a hashed password.
private static int	log2(int n)
static String	scrypt(String passwd, int N, int r, int p)	Hash the supplied plaintext password and generate output in the format described in SCryptUtil.

Methods inherited from class Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

SCryptUtil

public SCryptUtil()

Method Details

scrypt

public static String scrypt(String passwd,
 int N,
 int r,
 int p)

Hash the supplied plaintext password and generate output in the format described in SCryptUtil.

Parameters:

passwd - Password.

N - CPU cost parameter.

r - Memory cost parameter.

p - Parallelization parameter.

Returns:

The hashed password.

check

public static boolean check(String passwd,
 String hashed)

Compare the supplied plaintext password to a hashed password.

Parameters:

passwd - Plaintext password.

hashed - scrypt hashed password.

Returns:

true if passwd matches hashed value.

log2

private static int log2(int n)