com.nimbusds.srp6

Class SRP6VerifierGenerator

java.lang.Object

com.nimbusds.srp6.SRP6VerifierGenerator

public class SRP6VerifierGenerator
extends Object

Generator of password verifier 'v' values.

SRP6Routines.generateRandomSalt(int) may be used to create a random salt 's' of a specified byte size.

Author:

Vladimir Dzhuvinov

Constructor Summary

Constructors

Constructor and Description
SRP6VerifierGenerator(SRP6CryptoParams config) Creates a new generator of password verifier 'v' values.

Method Summary

Methods

Modifier and Type	Method and Description
static byte[]	generateRandomSalt() Generates a random 16-byte salt 's'.
static byte[]	generateRandomSalt(int numBytes) Generates a random salt 's'.
BigInteger	generateVerifier(BigInteger salt, String password) Generates a new verifier 'v' from the specified parameters with the user identifier 'I' omitted.
BigInteger	generateVerifier(BigInteger salt, String userID, String password) Generates a new verifier 'v' from the specified parameters.
BigInteger	generateVerifier(byte[] salt, byte[] password) Generates a new verifier 'v' from the specified parameters with the user identifier 'I' omitted.
BigInteger	generateVerifier(byte[] salt, byte[] userID, byte[] password) Generates a new verifier 'v' from the specified parameters.
XRoutine	getXRoutine() Gets the custom routine for the password key 'x' computation.
void	setXRoutine(XRoutine routine) Sets a custom routine for the password key 'x' computation.

Methods inherited from class java.lang.Object

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

Constructor Detail

SRP6VerifierGenerator

public SRP6VerifierGenerator(SRP6CryptoParams config)

Creates a new generator of password verifier 'v' values.

Parameters:

config - The SRP-6a crypto parameters configuration. Must not be null.

Method Detail

generateRandomSalt

public static byte[] generateRandomSalt(int numBytes)

Generates a random salt 's'.

This method is a shortcut to SRP6Routines.generateRandomSalt(int).

Parameters:

numBytes - The number of bytes the salt 's' must have.

Returns:

The salt 's' as a byte array.

generateRandomSalt

public static byte[] generateRandomSalt()

Generates a random 16-byte salt 's'.

This method is a shortcut to SRP6Routines.generateRandomSalt(int).

Returns:

The salt 's' as a byte array.

setXRoutine

public void setXRoutine(XRoutine routine)

Sets a custom routine for the password key 'x' computation.

Parameters:

routine - The password key 'x' routine or null to use the default one instead.

getXRoutine

public XRoutine getXRoutine()

Gets the custom routine for the password key 'x' computation.

Returns:

The routine instance or null if the default default one is used.

generateVerifier

public BigInteger generateVerifier(byte[] salt,
                          byte[] userID,
                          byte[] password)

Generates a new verifier 'v' from the specified parameters.

The verifier is computed as v = g^x (mod N). If a custom 'x' computation routine is set it will be used instead of the default one.

Tip: To convert a string to a byte array you can use String.getBytes() or String.getBytes(java.nio.charset.Charset). To convert a big integer to a byte array you can use BigInteger.toByteArray().

Parameters:

salt - The salt 's'. Must not be null.

userID - The user identity 'I'. May be null if the default 'x' routine is used or the custom one ignores it.

password - The user password 'P'. Must not be null.

Returns:

The resulting verifier 'v'.

generateVerifier

public BigInteger generateVerifier(BigInteger salt,
                          String userID,
                          String password)

Generates a new verifier 'v' from the specified parameters.

The verifier is computed as v = g^x (mod N). If a custom 'x' computation routine is set it will be used instead of the default one.

Parameters:

salt - The salt 's'. Must not be null.

userID - The user identity 'I', as an UTF-8 encoded string. May be null if the default 'x' routine is used or the custom one ignores it.

password - The user password 'P', as an UTF-8 encoded string. Must not be null.

Returns:

The resulting verifier 'v'.

generateVerifier

public BigInteger generateVerifier(byte[] salt,
                          byte[] password)

Generates a new verifier 'v' from the specified parameters with the user identifier 'I' omitted.

The verifier is computed as v = g^x (mod N). If a custom 'x' computation routine is set it must omit the user identity 'I' as well.

Tip: To convert a string to a byte array you can use String.getBytes() or String.getBytes(java.nio.charset.Charset). To convert a big integer to a byte array you can use BigInteger.toByteArray().

Parameters:

salt - The salt 's'. Must not be null.

password - The user password 'P'. Must not be null.

Returns:

The resulting verifier 'v'.

generateVerifier

public BigInteger generateVerifier(BigInteger salt,
                          String password)

Generates a new verifier 'v' from the specified parameters with the user identifier 'I' omitted.

The verifier is computed as v = g^x (mod N). If a custom 'x' computation routine is set it must omit the user identity 'I' as well.

Parameters:

salt - The salt 's'. Must not be null.

password - The user password 'P', as an UTF-8 encoded string. Must not be null.

Returns:

The resulting verifier 'v'.