001/*
002* The contents of this file are subject to the terms of the Common Development and
003* Distribution License (the License). You may not use this file except in compliance with the
004* License.
005*
006* You can obtain a copy of the License at legal/CDDLv1.0.txt. See the License for the
007* specific language governing permission and limitations under the License.
008*
009* When distributing Covered Software, include this CDDL Header Notice in each file and include
010* the License file at legal/CDDLv1.0.txt. If applicable, add the following below the CDDL
011* Header, with the fields enclosed by brackets [] replaced by your own identifying
012* information: "Portions copyright [year] [name of copyright owner]".
013*
014* Copyright 2014-2017 ForgeRock AS.
015*/
016package org.forgerock.json.jose.jwk;
017
018import java.security.Key;
019import javax.crypto.spec.SecretKeySpec;
020import org.forgerock.json.JsonException;
021import org.forgerock.json.jose.exceptions.FailedToLoadJWKException;
022import org.forgerock.json.jose.jws.JwsAlgorithm;
023
024/**
025 * Helper class to look up and return the keys from specific JWK implementation
026 * algorithm types.
027 */
028public class JWKLookup {
029
030    /**
031     * Lookup returns the key from the given json, under the assumption it's of the correct
032     * keyType.
033     *
034     * @param json JSON from which to attempt to generate a key
035     * @param keyType The type of key we expect to be generated from the JSON
036     * @return a valid key for verifying a JWT
037     * @throws FailedToLoadJWKException If there's an issue handling the loading of the JWK
038     */
039    public Key lookup(String json, KeyType keyType) throws FailedToLoadJWKException {
040        try {
041            switch (keyType) {
042            case RSA:
043                final RsaJWK rsaJWK = RsaJWK.parse(json);
044                return rsaJWK.toRSAPublicKey();
045            case EC:
046                final EcJWK ecJWK = EcJWK.parse(json);
047                return ecJWK.toECPublicKey();
048            case OCT:
049                final OctJWK octJWK = OctJWK.parse(json);
050                final String jwkKey = octJWK.getKey();
051
052                final Key key = new SecretKeySpec(jwkKey.getBytes(),
053                        JwsAlgorithm.parseCryptographicAlgorithm(octJWK.getAlgorithm()).getMdAlgorithm());
054
055                return key;
056            default:
057                throw new FailedToLoadJWKException("Unable to find handler for Key Type");
058            }
059        } catch (JsonException je) {
060            throw new FailedToLoadJWKException("Unable to generate Key from provided JSON", je);
061        }
062    }
063
064}