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 2013-2016 ForgeRock AS.
015 */
016
017package org.forgerock.json.jose.jwe;
018
019import org.forgerock.json.jose.exceptions.JweException;
020import org.forgerock.json.jose.jwe.handlers.encryption.AESKeyWrapEncryptionHandler;
021import org.forgerock.json.jose.jwe.handlers.encryption.DirectEncryptionHandler;
022import org.forgerock.json.jose.jwe.handlers.encryption.EncryptionHandler;
023import org.forgerock.json.jose.jwe.handlers.encryption.RSAEncryptionHandler;
024
025/**
026 * A service to get the appropriate EncryptionHandler for a specified Java Cryptographic encryption algorithm.
027 * <p>
028 * For details of all supported algorithms see {@link JweAlgorithm} and for all supported encryption methods see
029 * {@link EncryptionMethod}
030 *
031 * @since 2.0.0
032 */
033public class EncryptionManager {
034
035    /**
036     * Gets the appropriate EncryptionHandler that can perform the required encryption algorithm, as described by the
037     * JweAlgorithm and EncryptionMethod in the given JweHeader.
038     *
039     * @param header The JweHeader containing the JweAlgorithm and EncryptionMethod to get the EncryptionHandler for.
040     * @return The EncryptionHandler.
041     */
042    public EncryptionHandler getEncryptionHandler(JweHeader header) {
043
044        switch (header.getAlgorithm().getAlgorithmType()) {
045        case RSA:
046            return getEncryptionHandler(header.getAlgorithm(), header.getEncryptionMethod());
047        case DIRECT:
048            return getEncryptionHandler(header.getAlgorithm(), header.getEncryptionMethod());
049        case AES_KEYWRAP:
050            return getEncryptionHandler(header.getAlgorithm(), header.getEncryptionMethod());
051        default: {
052            throw new JweException("No Encryption Handler for unknown encryption algorithm, "
053                    + header.getAlgorithm() + ".");
054        }
055        }
056    }
057
058    /**
059     * Gets the appropriate EncryptionHandler that can perform the required encryption algorithm, as described by the
060     * JweAlgorithm and EncryptionMethod.
061     *
062     * @param algorithm The JweAlgorithm.
063     * @param encryptionMethod The EncryptionMethod.
064     * @return The EncryptionHandler.
065     */
066    private EncryptionHandler getEncryptionHandler(JweAlgorithm algorithm, EncryptionMethod encryptionMethod) {
067
068        switch (algorithm) {
069        case RSAES_PKCS1_V1_5:
070        case RSA_OAEP:
071        case RSA_OAEP_256:
072            return new RSAEncryptionHandler(encryptionMethod, algorithm);
073        case DIRECT:
074            return new DirectEncryptionHandler(encryptionMethod);
075        case A128KW:
076        case A192KW:
077        case A256KW:
078            return new AESKeyWrapEncryptionHandler(encryptionMethod);
079        default:
080            throw new JweException("No Encryption Handler for unknown encryption method, "
081                    + encryptionMethod + ", with algorithm,  " + algorithm + ".");
082        }
083    }
084}