/*
* Copyright 2012-2014 Brian Campbell
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.jose4j.jwk;
import org.jose4j.keys.EcKeyUtil;
import org.jose4j.keys.EllipticCurves;
import org.jose4j.lang.JoseException;
import org.jose4j.lang.JsonHelp;
import java.math.BigInteger;
import java.security.interfaces.ECPrivateKey;
import java.security.interfaces.ECPublicKey;
import java.security.spec.ECParameterSpec;
import java.security.spec.ECPoint;
import java.security.spec.EllipticCurve;
import java.util.Map;
/**
*/
public class EllipticCurveJsonWebKey extends PublicJsonWebKey
{
public static final String KEY_TYPE = "EC";
public static final String CURVE_MEMBER_NAME = "crv";
public static final String X_MEMBER_NAME = "x";
public static final String Y_MEMBER_NAME = "y";
public static final String PRIVATE_KEY_MEMBER_NAME = "d";
private String curveName;
public EllipticCurveJsonWebKey(ECPublicKey publicKey)
{
super(publicKey);
ECParameterSpec spec = publicKey.getParams();
EllipticCurve curve = spec.getCurve();
curveName = EllipticCurves.getName(curve);
}
public EllipticCurveJsonWebKey(Map<String, Object> params) throws JoseException
{
super(params);
curveName = JsonHelp.getString(params, CURVE_MEMBER_NAME);
ECParameterSpec curve = EllipticCurves.getSpec(curveName);
BigInteger x = getBigIntFromBase64UrlEncodedParam(params, X_MEMBER_NAME);
BigInteger y = getBigIntFromBase64UrlEncodedParam(params, Y_MEMBER_NAME);
EcKeyUtil keyUtil = new EcKeyUtil();
key = keyUtil.publicKey(x, y, curve);
checkForBareKeyCertMismatch();
if (params.containsKey(PRIVATE_KEY_MEMBER_NAME))
{
BigInteger d = getBigIntFromBase64UrlEncodedParam(params, PRIVATE_KEY_MEMBER_NAME);
privateKey = keyUtil.privateKey(d, curve);
}
}
public ECPublicKey getECPublicKey()
{
return (ECPublicKey) key;
}
public ECPrivateKey getEcPrivateKey()
{
return (ECPrivateKey) privateKey;
}
public String getKeyType()
{
return KEY_TYPE;
}
public String getCurveName()
{
return curveName;
}
private int getCoordinateByteLength()
{
ECParameterSpec spec = EllipticCurves.getSpec(getCurveName());
return (int) Math.ceil(spec.getCurve().getField().getFieldSize() / 8d);
}
protected void fillPublicTypeSpecificParams(Map<String,Object> params)
{
ECPublicKey ecPublicKey = getECPublicKey();
ECPoint w = ecPublicKey.getW();
int coordinateByteLength = getCoordinateByteLength();
putBigIntAsBase64UrlEncodedParam(params, X_MEMBER_NAME, w.getAffineX(), coordinateByteLength);
putBigIntAsBase64UrlEncodedParam(params, Y_MEMBER_NAME, w.getAffineY(), coordinateByteLength);
params.put(CURVE_MEMBER_NAME, getCurveName());
}
protected void fillPrivateTypeSpecificParams(Map<String,Object> params)
{
ECPrivateKey ecPrivateKey = getEcPrivateKey();
if (ecPrivateKey != null)
{
// This should be 'length of this octet
// string MUST be ceiling(log-base-2(n)/8) octets (where n is the order
// of the curve).' but this is the same thing for the prime integer curves
int coordinateByteLength = getCoordinateByteLength();
putBigIntAsBase64UrlEncodedParam(params, PRIVATE_KEY_MEMBER_NAME, ecPrivateKey.getS(), coordinateByteLength);
}
}
}