de.rtner.security.auth.spi

Class SimplePBKDF2

java.lang.Object

de.rtner.security.auth.spi.PBKDF2Engine

de.rtner.security.auth.spi.SimplePBKDF2

All Implemented Interfaces:

PBKDF2

public class SimplePBKDF2
extends PBKDF2Engine

PBKDF2 convenience object that comes pre-configured.

• Salt Generator: "SHA1PRNG"
• Hash Algorithm: "HmacSHA1"
• Iterations: 1000
• Encoding: "ISO-8859-1"

Note: this class is not thread-safe. Create a new instance for each thread.

See Also:

RFC 2898

Field Summary

Fields

Modifier and Type	Field and Description
protected PBKDF2Formatter	formatter
protected int	saltSize
protected java.security.SecureRandom	sr

Fields inherited from class de.rtner.security.auth.spi.PBKDF2Engine

parameters, prf

Constructor Summary

Constructors

Modifier	Constructor and Description
	SimplePBKDF2() Constructor for PBKDF2 implementation object that uses defaults.
	SimplePBKDF2(int saltSize, int iterationCount) Constructor for PBKDF2 implementation object.
protected	SimplePBKDF2(int saltSize, PBKDF2Parameters parameters) Extension point.

Method Summary

Modifier and Type	Method and Description
java.lang.String	deriveKeyFormatted(java.lang.String inputPassword) Derive key from password, then format.
protected byte[]	generateSalt() Generate Salt.
PBKDF2Formatter	getFormatter()
int	getSaltSize()
void	setFormatter(PBKDF2Formatter formatter)
void	setSaltSize(int saltSize) Set the desired salt size.
boolean	verifyKeyFormatted(java.lang.String formatted, java.lang.String candidatePassword) Verification function.

Methods inherited from class de.rtner.security.auth.spi.PBKDF2Engine

_F, assertPRF, ceil, deriveKey, deriveKey, getParameters, getPseudoRandomFunction, INT, main, PBKDF2, setParameters, setPseudoRandomFunction, verifyKey, xor

Methods inherited from class java.lang.Object

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

Field Detail

saltSize

protected int saltSize

sr

protected java.security.SecureRandom sr

formatter

protected PBKDF2Formatter formatter

Constructor Detail

SimplePBKDF2

public SimplePBKDF2()

Constructor for PBKDF2 implementation object that uses defaults.

SimplePBKDF2

protected SimplePBKDF2(int saltSize,
                       PBKDF2Parameters parameters)

Extension point. Derived classes can call this, then initialize the other members as desired.

Parameters:

saltSize - Salt size.

parameters - Parameters object.

SimplePBKDF2

public SimplePBKDF2(int saltSize,
                    int iterationCount)

Constructor for PBKDF2 implementation object.

Parameters:

saltSize - Salt size.

iterationCount - Iteration count.

Method Detail

getFormatter

public PBKDF2Formatter getFormatter()

setFormatter

public void setFormatter(PBKDF2Formatter formatter)

getSaltSize

public int getSaltSize()

setSaltSize

public void setSaltSize(int saltSize)

Set the desired salt size.

Parameters:

saltSize - Must be positive. Zero or less are rejected.

deriveKeyFormatted

public java.lang.String deriveKeyFormatted(java.lang.String inputPassword)

Derive key from password, then format.

Parameters:

inputPassword - The password to derive key from.

Returns:

"salt:iteration-count:derived-key" (depends on effective formatter)

generateSalt

protected byte[] generateSalt()

Generate Salt. Default is 8 Bytes obtained from SecureRandom.

Returns:

Random Bytes

verifyKeyFormatted

public boolean verifyKeyFormatted(java.lang.String formatted,
                                  java.lang.String candidatePassword)

Verification function.

Parameters:

formatted - "salt:iteration-count:derived-key" (depends on effective formatter). This value should come from server-side storage.

candidatePassword - The password that is checked against the formatted reference data. This value will usually be supplied by the "user" or "client".

Returns:

true verification OK. false verification failed or formatter unable to decode input value as PBKDF2 parameters.