Package anlavn.hash

Class BCrypt

java.lang.Object

anlavn.hash.BCrypt

public class BCrypt
extends Object

The BCrypt class supports to OpenBSD-style Blowfish password hashing for Java. Bcrypt is a password-hashing function designed by Niels Provos and David Mazières, based on the Blowfish cipher and presented at USENIX in 1999.

Constructor Summary

Constructors

Constructor	Description
BCrypt()

Method Summary

Modifier and Type	Method	Description
static final boolean	check(String strToCheck, String hashedCode)	Use this method to check if the original string matches a previously hashed one.
static final String	encrypt(String strToEncrypt, String salt)	Use this method to encrypt the original string.
static final String	genSalt()	Use this method to generate a salt for use with the BCrypt.Encrypt() method.
static final String	genSalt(int log_rounds)	Use this method to generate a salt for use with the BCrypt.Encrypt() method.
static final String	genSalt(int log_rounds, SecureRandom random)	Use this method to generate a salt for use with the BCrypt.Encrypt() method.

Methods inherited from class java.lang.Object

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

Constructor Details

BCrypt

public BCrypt()

Method Details

encrypt

public static final String encrypt(String strToEncrypt,
 String salt)

Use this method to encrypt the original string.

Parameters:

strToEncrypt - is the original string need encrypt.

salt - the salt to hash.

Returns:

a BCrypt hash code of the original string.

See Also:

• check(java.lang.String, java.lang.String)
• genSalt()
• genSalt(int)
• genSalt(int, java.security.SecureRandom)

check

public static final boolean check(String strToCheck,
 String hashedCode)

Use this method to check if the original string matches a previously hashed one.

Parameters:

strToCheck - is the original string need to check.

hashedCode - is BCrypt hash code of the original string.

Returns:

true if the strToCheck match hashCode, false otherwise.

See Also:

• encrypt(java.lang.String, java.lang.String)

genSalt

public static final String genSalt()

Use this method to generate a salt for use with the BCrypt.Encrypt() method.

Returns:

an encoded salt value.

See Also:

• encrypt(java.lang.String, java.lang.String)
• genSalt(int)
• genSalt(int, java.security.SecureRandom)

genSalt

public static final String genSalt(int log_rounds)

Use this method to generate a salt for use with the BCrypt.Encrypt() method.

Parameters:

log_rounds - is the Logarithm₂ of the number of rounds of hashing to apply. Has a value between 4 and 30, default is 10, the larger the value, the longer the encryption time. The work factor therefore increases as 2^log_rounds time.
Example: log_rounds = 12 => 2¹² = 4,096 iterations.

Returns:

an encoded salt value.

See Also:

• encrypt(java.lang.String, java.lang.String)
• genSalt()
• genSalt(int, java.security.SecureRandom)

genSalt

public static final String genSalt(int log_rounds,
 SecureRandom random)

Use this method to generate a salt for use with the BCrypt.Encrypt() method.

Parameters:

log_rounds - is the Logarithm₂ of the number of rounds of hashing to apply. Has a value between 4 and 30, default is 10, the larger the value, the longer the encryption time. The work factor therefore increases as 2^log_rounds time.
Example: log_rounds = 12 => 2¹² = 4,096 iterations.

random - is an instance of SecureRandom to use.

Returns:

an encoded salt value.

See Also:

• encrypt(java.lang.String, java.lang.String)
• genSalt()
• genSalt(int)