Package com.bastiaanjansen.otp

Class TOTPGenerator

java.lang.Object

com.bastiaanjansen.otp.TOTPGenerator

public final class TOTPGenerator
extends Object

Generates time-based one-time passwords

Author:

Bastiaan Jansen

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	TOTPGenerator.Builder

Method Summary

Modifier and Type	Method	Description
String	at(long secondsPast1970)	Generate a time-based one-time password for a specific time based on seconds past 1970
String	at(Instant instant)	Generate a time-based one-time password for a Java instant
String	at(Date date)	Generate a time-based one-time password for a specific date
Duration	durationUntilNextTimeWindow()	Calculates time until next time window will be reached and a new totp should be generated
static TOTPGenerator	fromURI(URI uri)	Build a TOTPGenerator from an OTPAuth URI
HMACAlgorithm	getAlgorithm()
Clock	getClock()
int	getPasswordLength()
Duration	getPeriod()
URI	getURI(String issuer)	Create a OTPAuth URI for easy on-boarding with only an issuer
URI	getURI(String issuer, String account)	Create a OTPAuth URI for easy user on-boarding with an issuer and account name
String	now()	Generate a time-based one-time password for current time interval instant
boolean	verify(String code)	Checks whether a code is valid for a specific counter
boolean	verify(String code, int delayWindow)	Checks whether a code is valid for a specific counter taking a delay window into account
static TOTPGenerator	withDefaultValues(byte[] secret)

Methods inherited from class java.lang.Object

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

Method Detail

fromURI

public static TOTPGenerator fromURI(URI uri)
                             throws URISyntaxException

Build a TOTPGenerator from an OTPAuth URI

Parameters:

uri - OTPAuth URI

Returns:

TOTP

Throws:

URISyntaxException - when URI cannot be parsed

withDefaultValues

public static TOTPGenerator withDefaultValues(byte[] secret)

now

public String now()
           throws IllegalStateException

Generate a time-based one-time password for current time interval instant

Returns:

generated TOTP code

Throws:

IllegalStateException - when code could not be generated

at

public String at(Instant instant)
          throws IllegalStateException

Generate a time-based one-time password for a Java instant

Parameters:

instant - an instant

Returns:

generated TOTP code

Throws:

IllegalStateException - when code could not be generated

at

public String at(Date date)
          throws IllegalStateException

Generate a time-based one-time password for a specific date

Parameters:

date - specific date

Returns:

generated TOTP code

Throws:

IllegalStateException - when code could not be generated

at

public String at(long secondsPast1970)
          throws IllegalArgumentException

Generate a time-based one-time password for a specific time based on seconds past 1970

Parameters:

secondsPast1970 - seconds past 1970

Returns:

generated TOTP code

Throws:

IllegalArgumentException - when code could not be generated

verify

public boolean verify(String code)

Checks whether a code is valid for a specific counter

Parameters:

code - an OTP code

Returns:

a boolean, true if code is valid, otherwise false

verify

public boolean verify(String code,
                      int delayWindow)

Checks whether a code is valid for a specific counter taking a delay window into account

Parameters:

code - an OTP code

delayWindow - window in which a code can still be deemed valid

Returns:

a boolean, true if code is valid, otherwise false

getPeriod

public Duration getPeriod()

getClock

public Clock getClock()

getAlgorithm

public HMACAlgorithm getAlgorithm()

getPasswordLength

public int getPasswordLength()

getURI

public URI getURI(String issuer)
           throws URISyntaxException

Create a OTPAuth URI for easy on-boarding with only an issuer

Parameters:

issuer - name

Returns:

generated OTPAuth URI

Throws:

URISyntaxException - when URI cannot be created

getURI

public URI getURI(String issuer,
                  String account)
           throws URISyntaxException

Create a OTPAuth URI for easy user on-boarding with an issuer and account name

Parameters:

issuer - name

account - name

Returns:

generated OTPAuth URI

Throws:

URISyntaxException - when URI cannot be created

durationUntilNextTimeWindow

public Duration durationUntilNextTimeWindow()

Calculates time until next time window will be reached and a new totp should be generated

Returns:

a duration object with duration until next time window