001/*
002 * nimbus-jose-jwt
003 *
004 * Copyright 2012-2016, Connect2id Ltd and contributors.
005 *
006 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use
007 * this file except in compliance with the License. You may obtain a copy of the
008 * License at
009 *
010 *    http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing, software distributed
013 * under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
014 * CONDITIONS OF ANY KIND, either express or implied. See the License for the
015 * specific language governing permissions and limitations under the License.
016 */
017
018package com.nimbusds.jose.jwk.gen;
019
020
021import java.security.InvalidAlgorithmParameterException;
022import java.security.KeyPair;
023import java.security.KeyPairGenerator;
024import java.security.NoSuchAlgorithmException;
025import java.security.interfaces.ECPublicKey;
026import java.security.spec.ECParameterSpec;
027
028import com.nimbusds.jose.JOSEException;
029import com.nimbusds.jose.jwk.Curve;
030import com.nimbusds.jose.jwk.ECKey;
031
032
033/**
034 * Elliptic Curve (EC) JSON Web Key (JWK) generator.
035 *
036 * <p>Supported curves:
037 *
038 * <ul>
039 *     <li>{@link Curve#P_256 P-256}
040 *     <li>{@link Curve#SECP256K1 secp256k1}
041 *     <li>{@link Curve#P_384 P-384}
042 *     <li>{@link Curve#P_521 P-512}
043 * </ul>
044 *
045 * @author Vladimir Dzhuvinov
046 * @version 2019-04-17
047 */
048public class ECKeyGenerator extends JWKGenerator<ECKey> {
049        
050        
051        /**
052         * The curve.
053         */
054        private final Curve crv;
055        
056        
057        /**
058         * Creates a new EC JWK generator.
059         *
060         * @param crv The curve. Must not be {@code null}.
061         */
062        public ECKeyGenerator(final Curve crv) {
063        
064                if (crv == null) {
065                        throw new IllegalArgumentException("The curve must not be null");
066                }
067                this.crv = crv;
068        }
069        
070        
071        @Override
072        public ECKey generate()
073                throws JOSEException  {
074                
075                ECParameterSpec ecSpec = crv.toECParameterSpec();
076                
077                KeyPairGenerator generator;
078                try {
079                        if (keyStore != null) {
080                                // For PKCS#11
081                                generator = KeyPairGenerator.getInstance("EC", keyStore.getProvider());
082                        } else {
083                                generator = KeyPairGenerator.getInstance("EC");
084                        }
085                        generator.initialize(ecSpec);
086                } catch (NoSuchAlgorithmException | InvalidAlgorithmParameterException e) {
087                        throw new JOSEException(e.getMessage(), e);
088                }
089                
090                KeyPair kp = generator.generateKeyPair();
091                
092                ECKey.Builder builder = new ECKey.Builder(crv, (ECPublicKey) kp.getPublic())
093                        .privateKey(kp.getPrivate())
094                        .keyUse(use)
095                        .keyOperations(ops)
096                        .algorithm(alg)
097                        .keyStore(keyStore);
098                
099                if (x5tKid) {
100                        builder.keyIDFromThumbprint();
101                } else {
102                        builder.keyID(kid);
103                }
104                
105                return builder.build();
106        }
107}