Package com.helger.security.password.hash

Class AbstractPasswordHashCreatorPBKDF2

java.lang.Object

com.helger.security.password.hash.AbstractPasswordHashCreator

com.helger.security.password.hash.AbstractPasswordHashCreatorPBKDF2

All Implemented Interfaces:

IPasswordHashCreator

Direct Known Subclasses:

PasswordHashCreatorPBKDF2_SHA256_1000_48

public abstract class AbstractPasswordHashCreatorPBKDF2
extends AbstractPasswordHashCreator

Base class for IPasswordHashCreator using the PBKDF2 algorithm.

Author:

Philip Helger

Field Summary

Fields

Modifier and Type	Field	Description
protected int	m_nHashBytes
protected int	m_nIterations
protected String	m_sPBKDF2AlgorithmName

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	AbstractPasswordHashCreatorPBKDF2(String sAlgorithmName, String sPBKDF2AlgorithmName, int nIterations, int nBytes)

Method Summary

Modifier and Type	Method	Description
String	createPasswordHash(IPasswordSalt aSalt, String sPlainTextPassword)	The method to create a message digest hash from a password.
protected static byte[]	pbkdf2(char[] aPassword, byte[] aSalt, int nIterations, int nBytes, String sPBKDF2AlgorithmName)	Computes the PBKDF2 hash of a password.
boolean	requiresSalt()

Methods inherited from class com.helger.security.password.hash.AbstractPasswordHashCreator

getAlgorithmName, toString

Methods inherited from class java.lang.Object

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

Field Detail

m_sPBKDF2AlgorithmName

protected final String m_sPBKDF2AlgorithmName

m_nIterations

protected final int m_nIterations

m_nHashBytes

protected final int m_nHashBytes

Constructor Detail

AbstractPasswordHashCreatorPBKDF2

protected AbstractPasswordHashCreatorPBKDF2(@Nonnull @Nonempty
                                            String sAlgorithmName,
                                            @Nonnull @Nonempty
                                            String sPBKDF2AlgorithmName,
                                            @Nonnegative
                                            int nIterations,
                                            @Nonnegative
                                            int nBytes)

Method Detail

requiresSalt

public final boolean requiresSalt()

Returns:

true if this hash creator requires a salt, false if not.

pbkdf2

@Nonnull
protected static final byte[] pbkdf2(@Nonnull
                                     char[] aPassword,
                                     @Nonnull
                                     byte[] aSalt,
                                     @Nonnegative
                                     int nIterations,
                                     @Nonnegative
                                     int nBytes,
                                     @Nonnull @Nonempty
                                     String sPBKDF2AlgorithmName)

Computes the PBKDF2 hash of a password.

Parameters:

aPassword - the password to hash.

aSalt - the salt

nIterations - the iteration count (slowness factor)

nBytes - the length of the hash to compute in bytes

sPBKDF2AlgorithmName - The SecretKeyFactory parameter to use. May neither be null nor empty.

Returns:

the PBDKF2 hash of the password

createPasswordHash

@Nonnull
public String createPasswordHash(@Nonnull
                                 IPasswordSalt aSalt,
                                 @Nonnull
                                 String sPlainTextPassword)

Description copied from interface: IPasswordHashCreator

The method to create a message digest hash from a password.

Parameters:

aSalt - Optional salt to be used. This parameter is only null for backwards compatibility reasons.

sPlainTextPassword - Plain text password. May not be null.

Returns:

The String representation of the password hash. Must be valid to encode in UTF-8.