org.cryptimeleon.craco.sig.ps

Class PSExtendedVerificationKey

java.lang.Object

org.cryptimeleon.craco.sig.ps.PSVerificationKey

org.cryptimeleon.craco.sig.ps.PSExtendedVerificationKey

All Implemented Interfaces:

CommonInput, VerificationKey, org.cryptimeleon.math.hash.UniqueByteRepresentable, org.cryptimeleon.math.serialization.Representable

public class PSExtendedVerificationKey
extends PSVerificationKey
implements VerificationKey, org.cryptimeleon.math.hash.UniqueByteRepresentable, CommonInput

Extension of the verification key for a Pointcheval Sanders Signature Scheme to store the generator g and the group elements Y_i from group 1. These parameters are generated by PSExtendedSignatureScheme.generateKeyPair(int). The reason for storing those further variables is the combined usage of the PSExtendedSignatureScheme with the PedersenCommitmentScheme is for being able blind and unblind messages before and after signing them. This is achieved by using the same g and Y_i in the PedersenCommitmentScheme as provided by the PSExtendedSignatureScheme. This allows a user to receive a signature on a commitment for a message and to then calculate the signature for the uncommitted message, and thereby receive a signature of a signer for a message without the signer knowing the content of the message.

Nested Class Summary

Nested classes/interfaces inherited from interface org.cryptimeleon.craco.protocols.CommonInput

CommonInput.CommonInputVector, CommonInput.EmptyCommonInput

Field Summary

Fields inherited from class org.cryptimeleon.craco.sig.ps.PSVerificationKey

group2ElementsTildeYi, group2ElementTildeG, group2ElementTildeX

Fields inherited from interface org.cryptimeleon.craco.protocols.CommonInput

EMPTY

Constructor Summary

Constructors

Constructor and Description
PSExtendedVerificationKey(org.cryptimeleon.math.structures.groups.GroupElement group1Element, org.cryptimeleon.math.structures.groups.cartesian.GroupElementVector group1ElementsYi, org.cryptimeleon.math.structures.groups.GroupElement group2ElementTildeG, org.cryptimeleon.math.structures.groups.GroupElement group2ElementTildeX, org.cryptimeleon.math.structures.groups.cartesian.GroupElementVector group2ElementsTildeYi) Extended constructor for the extended verification key in the ACS allowing direct instantiation.
PSExtendedVerificationKey(org.cryptimeleon.math.structures.groups.Group groupG1, org.cryptimeleon.math.structures.groups.Group groupG2, org.cryptimeleon.math.serialization.Representation repr) Extended constructor for the extended verification key in the ACS (from representation).

Method Summary

Modifier and Type	Method and Description
boolean	equals(java.lang.Object o)
org.cryptimeleon.math.structures.groups.GroupElement	getGroup1ElementG()
org.cryptimeleon.math.structures.groups.cartesian.GroupElementVector	getGroup1ElementsYi()
org.cryptimeleon.math.serialization.Representation	getRepresentation()
byte[]	getUniqueByteRepresentation()
int	hashCode()
org.cryptimeleon.math.hash.ByteAccumulator	updateAccumulator(org.cryptimeleon.math.hash.ByteAccumulator byteAccumulator)

Methods inherited from class org.cryptimeleon.craco.sig.ps.PSVerificationKey

getGroup2ElementsTildeYi, getGroup2ElementTildeG, getGroup2ElementTildeX, getNumberOfMessages

Methods inherited from class java.lang.Object

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

Constructor Detail

PSExtendedVerificationKey

public PSExtendedVerificationKey(org.cryptimeleon.math.structures.groups.GroupElement group1Element,
                                 org.cryptimeleon.math.structures.groups.cartesian.GroupElementVector group1ElementsYi,
                                 org.cryptimeleon.math.structures.groups.GroupElement group2ElementTildeG,
                                 org.cryptimeleon.math.structures.groups.GroupElement group2ElementTildeX,
                                 org.cryptimeleon.math.structures.groups.cartesian.GroupElementVector group2ElementsTildeYi)

Extended constructor for the extended verification key in the ACS allowing direct instantiation.

Parameters:

group1Element - GroupElement g is a generator from Group 1

group1ElementsYi - Array of GroupElement containing Y_i from Group 1

group2ElementTildeG - GroupElement g_Tilde is a generator from Group 2

group2ElementTildeX - GroupElement x_Tilde from Group 1

group2ElementsTildeYi - Array of GroupElement containing Y_i_Tilde from Group 2

PSExtendedVerificationKey

public PSExtendedVerificationKey(org.cryptimeleon.math.structures.groups.Group groupG1,
                                 org.cryptimeleon.math.structures.groups.Group groupG2,
                                 org.cryptimeleon.math.serialization.Representation repr)

Extended constructor for the extended verification key in the ACS (from representation).

Parameters:

groupG1 - Group group 1 from BilinearMap

groupG2 - Group group 2 from BilinearMap

repr - Representation of PSExtendedVerificationKey

Method Detail

getRepresentation

public org.cryptimeleon.math.serialization.Representation getRepresentation()

Specified by:

getRepresentation in interface org.cryptimeleon.math.serialization.Representable

Overrides:

getRepresentation in class PSVerificationKey

getGroup1ElementG

public org.cryptimeleon.math.structures.groups.GroupElement getGroup1ElementG()

getGroup1ElementsYi

public org.cryptimeleon.math.structures.groups.cartesian.GroupElementVector getGroup1ElementsYi()

equals

public boolean equals(java.lang.Object o)

Overrides:

equals in class PSVerificationKey

hashCode

public int hashCode()

Overrides:

hashCode in class PSVerificationKey

updateAccumulator

public org.cryptimeleon.math.hash.ByteAccumulator updateAccumulator(org.cryptimeleon.math.hash.ByteAccumulator byteAccumulator)

Specified by:

updateAccumulator in interface org.cryptimeleon.math.hash.UniqueByteRepresentable

getUniqueByteRepresentation

public byte[] getUniqueByteRepresentation()

Specified by:

getUniqueByteRepresentation in interface org.cryptimeleon.math.hash.UniqueByteRepresentable