org.cryptacular.bean

Class BCryptHashBean

java.lang.Object

org.cryptacular.bean.BCryptHashBean

All Implemented Interfaces:

HashBean<String>

public class BCryptHashBean
extends Object
implements HashBean<String>

HashBean implementation that uses the bcrypt algorithm for hashing. Hash strings of the following format are supported:
$2n$cost$xxxxxxxxxxxxxxxxxxxxxxxxyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyy where: n is an optional bcrypt algorithm version (typically "a" or "b") 4 ≤ cost ≤ 31 x is 22 characters of encoded salt y is 31 characters of encoded hash bytes

The encoding for salt and hash bytes is a variant of base-64 encoding without padding in the following alphabet:

./ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789

Author:

Middleware Services

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	BCryptHashBean.BCryptParameters Handles encoding and decoding a bcrypt hash of the form $2n$cost$xxxxxxxxxxxxxxxxxxxxxxxxyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyy.

Constructor Summary

Constructors

Constructor and Description
BCryptHashBean() Creates a new instance.
BCryptHashBean(int costFactor) Creates a new instance that uses the given cost factor when hashing.

Method Summary

Modifier and Type	Method and Description
boolean	compare(String hash, Object... data) Compares a bcrypt hash of the form $2n$cost$xxxxxxxxxxxxxxxxxxxxxxxxyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyy with the computed hash from the given password.
String	hash(Object... data) Compute a bcrypt hash of the form $2n$cost$xxxxxxxxxxxxxxxxxxxxxxxxyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyy given a salt and a password.
void	setCost(int costFactor) Sets the bcrypt cost factor.
void	setVersion(String ver) Sets the bcrypt version.

Methods inherited from class java.lang.Object

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

Constructor Detail

BCryptHashBean

public BCryptHashBean()

Creates a new instance.

BCryptHashBean

public BCryptHashBean(int costFactor)

Creates a new instance that uses the given cost factor when hashing.

Parameters:

costFactor - BCrypt cost in the range [4, 31].

Method Detail

setCost

public void setCost(int costFactor)

Sets the bcrypt cost factor.

Parameters:

costFactor - BCrypt cost in the range [4, 31].

setVersion

public void setVersion(String ver)

Sets the bcrypt version.

Parameters:

ver - Bcrypt version, e.g. "2b"

hash

public String hash(Object... data)
            throws CryptoException

Compute a bcrypt hash of the form $2n$cost$xxxxxxxxxxxxxxxxxxxxxxxxyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyy given a salt and a password.

Specified by:

hash in interface HashBean<String>

Parameters:

data - A 2-element array containing salt and password. The salt may be encoded per the bcrypt standard or raw bytes.

Returns:

An encoded bcrypt hash, yyyyyyyyyyyyyyyyyyyyyyyyyyyyyyy in the specification above.

Throws:

CryptoException - on bcrypt algorithm errors.

compare

public boolean compare(String hash,
                       Object... data)
                throws CryptoException,
                       StreamException

Compares a bcrypt hash of the form $2n$cost$xxxxxxxxxxxxxxxxxxxxxxxxyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyy with the computed hash from the given password. The bcrypt algorithm parameters are derived from the reference bcrypt hash string.

Specified by:

compare in interface HashBean<String>

Parameters:

data - A 1-element array containing password.

hash - Known hash value.

Returns:

True if the computed hash is exactly equal to the reference hash, false otherwise.

Throws:

CryptoException - on bcrypt algorithm errors.

StreamException - on stream IO errors.