Package com.bastiaanjansen.otp

Class TOTPGenerator

java.lang.Object

com.bastiaanjansen.otp.OneTimePasswordGenerator

com.bastiaanjansen.otp.TOTPGenerator

public class TOTPGenerator
extends OneTimePasswordGenerator

Generates time-based one-time passwords

Author:

Bastiaan Jansen

See Also:

OneTimePasswordGenerator

Field Summary

Fields

Modifier and Type	Field	Description
static java.time.Duration	DEFAULT_PERIOD	Default time interval for a time-based one-time password

Fields inherited from class com.bastiaanjansen.otp.OneTimePasswordGenerator

algorithm, DEFAULT_HMAC_ALGORITHM, DEFAULT_PASSWORD_LENGTH, passwordLength, secret

Constructor Summary

Constructors

Constructor	Description
TOTPGenerator(int passwordLength, HMACAlgorithm algorithm, String secret)	Constructs generator with custom password length and hashing algorithm
TOTPGenerator(int passwordLength, String secret)	Constructs generator with custom password length
TOTPGenerator(int passwordLength, java.time.Duration period, HMACAlgorithm algorithm, String secret)	Constructs generator with custom password length, time interval and hashing algorithm
TOTPGenerator(int passwordLength, java.time.Duration period, String secret)	Constructs generator with custom password length and period
TOTPGenerator(HMACAlgorithm algorithm, String secret)	Constructs generator with custom hashing algorithm and default time interval
TOTPGenerator(String secret)	Constructs generator
TOTPGenerator(URI uri)	Constructs generator from a OTPAuth URI
TOTPGenerator(java.time.Duration period, HMACAlgorithm algorithm, String secret)	Constructs generator with custom time interval and hashing algorithm
TOTPGenerator(java.time.Duration period, String secret)	Constructs generator with custom time interval

Method Summary

Modifier and Type	Method	Description
String	generate()	Generate a time-based one-time password for current time interval instant
String	generate(long secondsPast1970)	Generate a time-based one-time password for a specific time based on seconds past 1970
String	generate(java.time.Instant instant)	Generate a time-based one-time password for a Java instant
String	generate(Date date)	Generate a time-based one-time password for a specific date
java.time.Duration	getPeriod()
URI	getURI(String issuer)	Create a OTPAuth URI for easy onboarding 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
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

Methods inherited from class com.bastiaanjansen.otp.OneTimePasswordGenerator

generate, getAlgorithm, getPasswordLength, getSecret, getURI, verify, verify

Methods inherited from class java.lang.Object

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

Field Details

DEFAULT_PERIOD

public static final java.time.Duration DEFAULT_PERIOD

Default time interval for a time-based one-time password

Constructor Details

TOTPGenerator

public TOTPGenerator(String secret)

Constructs generator

Parameters:

secret - used to generate hash

TOTPGenerator

public TOTPGenerator(int passwordLength,
String secret)

Constructs generator with custom password length

Parameters:

passwordLength - number of digits for generated code in range 6...8

secret - used to generate hash

TOTPGenerator

public TOTPGenerator(java.time.Duration period,
String secret)

Constructs generator with custom time interval

Parameters:

period - time interval between new codes

secret - used to generate hash

TOTPGenerator

public TOTPGenerator(java.time.Duration period,
HMACAlgorithm algorithm,
String secret)

Constructs generator with custom time interval and hashing algorithm

Parameters:

period - time interval between new codes

algorithm - HMAC hash algorithm used to hash data

secret - used to generate hash

TOTPGenerator

public TOTPGenerator(HMACAlgorithm algorithm,
String secret)

Constructs generator with custom hashing algorithm and default time interval

Parameters:

algorithm - HMAC hash algorithm used to hash data

secret - used to generate hash

TOTPGenerator

public TOTPGenerator(int passwordLength,
java.time.Duration period,
String secret)

Constructs generator with custom password length and period

Parameters:

passwordLength - number of digits for generated code in range 6...8

period - time interval between new codes

secret - used to generate hash

TOTPGenerator

public TOTPGenerator(int passwordLength,
HMACAlgorithm algorithm,
String secret)

Constructs generator with custom password length and hashing algorithm

Parameters:

passwordLength - number of digits for generated code in range 6...8

algorithm - HMAC hash algorithm used to hash data

secret - used to generate hash

TOTPGenerator

public TOTPGenerator(int passwordLength,
java.time.Duration period,
HMACAlgorithm algorithm,
String secret)

Constructs generator with custom password length, time interval and hashing algorithm

Parameters:

passwordLength - number of digits for generated code in range 6...8

period - time interval between new codes

algorithm - HMAC hash algorithm used to hash data

secret - used to generate hash

TOTPGenerator

public TOTPGenerator(URI uri)
              throws UnsupportedEncodingException

Constructs generator from a OTPAuth URI

Parameters:

uri - OTPAuth URI

Throws:

UnsupportedEncodingException - when URI query can't be encoded

Method Details

generate

public String generate()
                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

generate

public String generate(java.time.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

generate

public String generate(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

generate

public String generate(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 java.time.Duration getPeriod()

getURI

public URI getURI(String issuer)
           throws URISyntaxException

Create a OTPAuth URI for easy onboarding 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