iaik.security.ec.common

Class AbstractECPublicKey

java.lang.Object

iaik.x509.PublicKeyInfo

iaik.security.ec.common.AbstractECPublicKey

All Implemented Interfaces:

iaik.asn1.ASN1Type, Serializable, Cloneable, ECKey, ECPublicKey, Key, PublicKey

Direct Known Subclasses:

ECPublicKey, EdPublicKey

public abstract class AbstractECPublicKey
extends iaik.x509.PublicKeyInfo
implements ECPublicKey, ECKey

Representation of a public key for EC algorithms and implementation of the ECPublicKey interface. It is derived from PublicKeyInfo which makes it suitable for use in X.509 certificates.

References:

[1] ANSI X9.62-2005, "American National Standard for Financial Services - The Elliptic Curve Digital Signature Algorithm (ECDSA)" , ASC X9, November 2005.

Author:

Christian Hanser, Sebastian Ramacher

See Also:

AbstractECPrivateKey, Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
protected iaik.asn1.OCTET_STRING	encodedPublicKey_ The ASN.1 representation of the public key
protected ECParameterSpec	params_ Domain parameters of the elliptic curve
protected ECPoint	w_ The public key (point on the elliptic curve) satisfying W = s*G, where s is the private key

Fields inherited from class iaik.x509.PublicKeyInfo

public_key_algorithm

Fields inherited from interface java.security.interfaces.ECPublicKey

serialVersionUID

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	AbstractECPublicKey() Creates a new instance; only for internal use
	AbstractECPublicKey(iaik.asn1.ASN1Object keyObj) Creates a new public key from an ASN.1 Object.
	AbstractECPublicKey(byte[] encoded) Creates a new PublicKey from an ASN.1 encoded DER byte array.
	AbstractECPublicKey(ECParameterSpec params, ECPoint w) Creates a new public key object.
protected	AbstractECPublicKey(ECParameterSpec params, ECPoint w, boolean check) Creates a new public key object.
	AbstractECPublicKey(InputStream is) Reads the DER or BER encoded public key info from an input stream.

Method Summary

Modifier and Type	Method and Description
protected abstract void	createEncodedPublicKey() Creates the ASN.1 public key structure.
protected byte[]	encode()
boolean	equals(Object obj)
ECParameterSpec	getParams() Returns the domain parameters of the associated elliptic curve.
ECPoint	getW()
int	hashCode()
abstract boolean	isValid() Determines whether this public key is valid according to its specification.

Methods inherited from class iaik.x509.PublicKeyInfo

clone, createPublicKeyInfo, decode, decode, getAlgorithm, getAlgorithmID, getEncoded, getFingerprint, getFormat, getPublicKey, getPublicKey, getPublicKey, getPublicKey, getPublicKey, getPublicKey, toASN1Object, toString, writeTo

Methods inherited from class java.lang.Object

finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface java.security.Key

getAlgorithm, getEncoded, getFormat

Methods inherited from interface iaik.security.ec.common.ECKey

getKeyLength

Field Detail

encodedPublicKey_

protected transient iaik.asn1.OCTET_STRING encodedPublicKey_

The ASN.1 representation of the public key

w_

protected transient ECPoint w_

The public key (point on the elliptic curve) satisfying W = s*G, where s is the private key

params_

protected transient ECParameterSpec params_

Domain parameters of the elliptic curve

Constructor Detail

AbstractECPublicKey

public AbstractECPublicKey(iaik.asn1.ASN1Object keyObj)
                    throws InvalidKeyException

Creates a new public key from an ASN.1 Object.

Parameters:

keyObj - the ASN.1 object holding the public key information

Throws:

InvalidKeyException - if the given ASN1Object does not hold a valid EC public key

AbstractECPublicKey

public AbstractECPublicKey(byte[] encoded)
                    throws InvalidKeyException

Creates a new PublicKey from an ASN.1 encoded DER byte array.

Parameters:

encoded - the byte array

Throws:

InvalidKeyException - thrown if the given encoded key could not be decoded

AbstractECPublicKey

protected AbstractECPublicKey(ECParameterSpec params,
                              ECPoint w,
                              boolean check)

Creates a new public key object.

Parameters:

params - the domain parameters of the elliptic curve

w - the point on the elliptic curve, satisfying W = s*G

check - check if w is a valid point

AbstractECPublicKey

public AbstractECPublicKey(ECParameterSpec params,
                           ECPoint w)

Creates a new public key object.

Parameters:

params - the domain parameters of the elliptic curve

w - the point on the elliptic curve, satisfying W = s*G

AbstractECPublicKey

public AbstractECPublicKey(InputStream is)
                    throws IOException,
                           InvalidKeyException

Reads the DER or BER encoded public key info from an input stream.

Parameters:

is - the input stream providing the data

Throws:

InvalidKeyException - if the provided key data is invalid

IOException - if the I/O error occurs

AbstractECPublicKey

protected AbstractECPublicKey()

Creates a new instance; only for internal use

Method Detail

createEncodedPublicKey

protected abstract void createEncodedPublicKey()

Creates the ASN.1 public key structure.

getParams

public ECParameterSpec getParams()

Description copied from interface: ECKey

Returns the domain parameters of the associated elliptic curve.

Specified by:

getParams in interface ECKey

Returns:

the curve domain parameters

getW

public ECPoint getW()

Specified by:

getW in interface ECPublicKey

encode

protected byte[] encode()

Specified by:

encode in class iaik.x509.PublicKeyInfo

isValid

public abstract boolean isValid()

Determines whether this public key is valid according to its specification.

Returns:

true, iff the public key could be validated

hashCode

public int hashCode()

Overrides:

hashCode in class iaik.x509.PublicKeyInfo

equals

public boolean equals(Object obj)

Overrides:

equals in class iaik.x509.PublicKeyInfo