001package com.nimbusds.oauth2.sdk.jose.jwk;
002
003
004import java.security.Key;
005import java.security.KeyPair;
006import java.util.Collections;
007import java.util.LinkedList;
008import java.util.List;
009
010import com.nimbusds.jose.JOSEException;
011import com.nimbusds.jose.jwk.*;
012
013
014/**
015 * Key converter.
016 */
017public class KeyConverter {
018        
019
020        /**
021         * Converts the specified list of JSON Web Keys (JWK) their standard
022         * Java class representation. Asymmetric {@link RSAKey RSA} and
023         * {@link ECKey EC key} pairs are converted to
024         * {@link java.security.PublicKey} and {@link java.security.PrivateKey}
025         * (if specified) objects. {@link OctetSequenceKey secret JWKs} are
026         * converted to {@link javax.crypto.SecretKey} objects. Key conversion
027         * exceptions are silently ignored.
028         *
029         * @param jwkList The JWK list. May be {@code null}.
030         *
031         * @return The converted keys, empty set if none or {@code null}.
032         */
033        public static List<Key> toJavaKeys(final List<JWK> jwkList) {
034
035                if (jwkList == null) {
036                        return Collections.emptyList();
037                }
038
039                List<Key> out = new LinkedList<>();
040                for (JWK jwk: jwkList) {
041                        try {
042                                if (jwk instanceof AssymetricJWK) {
043                                        KeyPair keyPair = ((AssymetricJWK)jwk).toKeyPair();
044                                        out.add(keyPair.getPublic()); // add public
045                                        if (keyPair.getPrivate() != null) {
046                                                out.add(keyPair.getPrivate()); // add private if present
047                                        }
048                                } else if (jwk instanceof SecretJWK) {
049                                        out.add(((SecretJWK)jwk).toSecretKey());
050                                }
051                        } catch (JOSEException e) {
052                                // ignore and continue
053                        }
054                }
055                return out;
056        }
057}