org.picketlink.idm.credential.util

Class TimeBasedOTP

java.lang.Object

org.picketlink.idm.credential.util.TimeBasedOTP

public class TimeBasedOTP
extends Object

TOTP: Time-based One-time Password Algorithm Based on http://tools.ietf.org/html/draft-mraihi-totp-timebased-06

Since:

Sep 20, 2010

Author:

anil saldhana

Field Summary

Fields

Modifier and Type	Field and Description
static String	DEFAULT_ALGORITHM
static int	DEFAULT_DELAY_WINDOW
static int	DEFAULT_INTERVAL_SECONDS
static int	DEFAULT_NUMBER_DIGITS
static String	HMAC_SHA1
static String	HMAC_SHA256
static String	HMAC_SHA512

Constructor Summary

Constructors

Constructor and Description
TimeBasedOTP()
TimeBasedOTP(String algorithm, int numberDigits, int timeIntervalInSeconds, int delayWindow)

Method Summary

Methods

Modifier and Type	Method and Description
String	generate(String secretKey) Generates a token.
String	generateTOTP(String key, String time, int returnDigits, String crypto) This method generates an TOTP value for the given set of parameters.
void	setCalendar(Calendar calendar)
boolean	validate(String token, byte[] secret) Validates a token using a secret key.

Methods inherited from class java.lang.Object

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

Field Detail

HMAC_SHA1

public static final String HMAC_SHA1

See Also:

Constant Field Values

HMAC_SHA256

public static final String HMAC_SHA256

See Also:

Constant Field Values

HMAC_SHA512

public static final String HMAC_SHA512

See Also:

Constant Field Values

DEFAULT_ALGORITHM

public static final String DEFAULT_ALGORITHM

See Also:

Constant Field Values

DEFAULT_NUMBER_DIGITS

public static final int DEFAULT_NUMBER_DIGITS

See Also:

Constant Field Values

DEFAULT_INTERVAL_SECONDS

public static final int DEFAULT_INTERVAL_SECONDS

See Also:

Constant Field Values

DEFAULT_DELAY_WINDOW

public static final int DEFAULT_DELAY_WINDOW

See Also:

Constant Field Values

Constructor Detail

TimeBasedOTP

public TimeBasedOTP()

TimeBasedOTP

public TimeBasedOTP(String algorithm,
            int numberDigits,
            int timeIntervalInSeconds,
            int delayWindow)

Parameters:

algorithm - the encryption algorithm

numberDigits - the number of digits for tokens

timeIntervalInSeconds - the number of seconds a token is valid

delayWindow - the number of previous intervals that should be used to validate tokens.

Method Detail

generate

public String generate(String secretKey)

Generates a token.

Parameters:

secretKey - the secret key to derive the token from.

generateTOTP

public String generateTOTP(String key,
                  String time,
                  int returnDigits,
                  String crypto)

This method generates an TOTP value for the given set of parameters.

Parameters:

key - the shared secret, HEX encoded

time - a value that reflects a time

returnDigits - number of digits to return

crypto - the crypto function to use

Returns:

A numeric String in base 10 that includes truncationDigits digits

Throws:

GeneralSecurityException

validate

public boolean validate(String token,
               byte[] secret)

Validates a token using a secret key.

Parameters:

token - OTP string to validate

secret - Shared secret

Returns:

setCalendar

public void setCalendar(Calendar calendar)