org.spongycastle.pqc.crypto.gmss

Class GMSSRootSig

java.lang.Object

org.spongycastle.pqc.crypto.gmss.GMSSRootSig

public class GMSSRootSig
extends java.lang.Object

This class implements the distributed signature generation of the Winternitz one-time signature scheme (OTSS), described in C.Dods, N.P. Smart, and M. Stam, "Hash Based Digital Signature Schemes", LNCS 3796, pages 96–115, 2005. The class is used by the GMSS classes.

Constructor Summary

Constructors

Constructor and Description
GMSSRootSig(Digest digest, byte[][] statByte, int[] statInt) This constructor regenerates a prior GMSSRootSig object used by the GMSSPrivateKeyASN.1 class
GMSSRootSig(Digest digest, int w, int height) The constructor generates the PRNG and initializes some variables

Method Summary

Modifier and Type	Method and Description
int	getLog(int intValue) This method returns the least integer that is greater or equal to the logarithm to the base 2 of an integer intValue.
byte[]	getSig()
byte[][]	getStatByte() This method returns the status byte array
int[]	getStatInt() This method returns the status int array
byte[]	getStatLong() Converts the long parameters into byte arrays to store it in statByte-Array
void	initSign(byte[] seed0, byte[] message) This method initializes the distributed sigature calculation.
java.lang.String	toString() returns a string representation of the instance
boolean	updateSign() This Method performs steps steps of distributed signature calculaion

Methods inherited from class java.lang.Object

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

Constructor Detail

GMSSRootSig

public GMSSRootSig(Digest digest,
                   byte[][] statByte,
                   int[] statInt)

This constructor regenerates a prior GMSSRootSig object used by the GMSSPrivateKeyASN.1 class

Parameters:

digest - an array of strings, containing the digest of the used hash function, the digest of the PRGN and the names of the corresponding providers

statByte - status byte array

statInt - status int array

GMSSRootSig

public GMSSRootSig(Digest digest,
                   int w,
                   int height)

The constructor generates the PRNG and initializes some variables

Parameters:

digest - an array of strings, containing the digest of the used hash function, the digest of the PRGN and the names of the corresponding providers

w - the winternitz parameter

height - the heigth of the tree

Method Detail

initSign

public void initSign(byte[] seed0,
                     byte[] message)

This method initializes the distributed sigature calculation. Variables are reseted and necessary steps are calculated

Parameters:

seed0 - the initial OTSseed

message - the massage which will be signed

updateSign

public boolean updateSign()

This Method performs steps steps of distributed signature calculaion

Returns:

true if signature is generated completly, else false

getSig

public byte[] getSig()

Returns:

The private OTS key

getLog

public int getLog(int intValue)

This method returns the least integer that is greater or equal to the logarithm to the base 2 of an integer intValue.

Parameters:

intValue - an integer

Returns:

The least integer greater or equal to the logarithm to the base 2 of intValue

getStatByte

public byte[][] getStatByte()

This method returns the status byte array

Returns:

statBytes

getStatInt

public int[] getStatInt()

This method returns the status int array

Returns:

statInt

getStatLong

public byte[] getStatLong()

Converts the long parameters into byte arrays to store it in statByte-Array

toString

public java.lang.String toString()

returns a string representation of the instance

Overrides:

toString in class java.lang.Object

Returns:

a string representation of the instance