DBCrypt class

BCrypt implements OpenBSD-style Blowfish password hashing using the scheme described in "A Future-Adaptable Password Scheme" by Niels Provos and David Mazieres.

This password hashing system tries to thwart off-line password cracking using a computationally-intensive hashing algorithm, based on Bruce Schneier's Blowfish cipher. The work factor of the algorithm is parameterised, so it can be increased as computers get faster.

Usage is really simple. To hash a password for the first time, call the hashpw method with a random salt, like this:

String pw_hash = new DBCrypt().hashpw(plain_password, new DBCrypt().gensalt());

To check whether a plaintext password matches one that has been hashed previously, use the checkpw method:

if (new DBCrypt().checkpw(candidate_password, stored_hash)) System.out.println("It matches"); else System.out.println("It does not match");

The gensalt() method takes an optional parameter (log_rounds) that determines the computational complexity of the hashing:

String strong_salt = new DBCrypt().gensalt(10) String stronger_salt = new DBCrypt().gensalt(12)

The amount of work increases exponentially (2**log_rounds), so each increment is twice as much work. The default log_rounds is 10, and the valid range is 4 to 31.

@author Erlantz Oniga @version 0.1.0

Constructors

DBCrypt()

Creates a new instance of DBCrypt if one wasn't created previously, otherwise it uses the previously created one.

factory

Properties

hashCode → int

The hash code for this object.

no setter, inherited

runtimeType → Type

A representation of the runtime type of the object.

no setter, inherited

Methods

checkpw(String plaintext, String hashed) → bool

Check that a plaintext password matches a previously hashed one.

gensalt() → String

Generate a salt for use with the BCrypt.hashpw method, selecting a reasonable default for the number of hashing rounds to apply.

gensaltWithRounds(int log_rounds) → String

Generate a salt for use with the BCrypt.hashpw method.

gensaltWithRoundsAndRandom(int log_rounds, Random random) → String

Generate a salt for use with the BCrypt.hashpw method.

hashpw(String password, String salt) → String

Hash a password using the OpenBSD bcrypt scheme.

noSuchMethod(Invocation invocation) → dynamic

Invoked when a nonexistent method or property is accessed.

inherited

toString() → String

A string representation of this object.

inherited

Operators

operator ==(Object other) → bool

The equality operator.

inherited