1 /* 2 * Copyright (c) 1997, 2007, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. Oracle designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Oracle in the LICENSE file that accompanied this code. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 26 package javax.crypto; 27 28 import java.security.*; 29 import java.security.spec.*; 30 31 /** 32 * This class defines the <i>Service Provider Interface</i> (<b>SPI</b>) 33 * for the <code>SecretKeyFactory</code> class. 34 * All the abstract methods in this class must be implemented by each 35 * cryptographic service provider who wishes to supply the implementation 36 * of a secret-key factory for a particular algorithm. 37 * 38 * <P> A provider should document all the key specifications supported by its 39 * secret key factory. 40 * For example, the DES secret-key factory supplied by the "SunJCE" provider 41 * supports <code>DESKeySpec</code> as a transparent representation of DES 42 * keys, and that provider's secret-key factory for Triple DES keys supports 43 * <code>DESedeKeySpec</code> as a transparent representation of Triple DES 44 * keys. 45 * 46 * @author Jan Luehe 47 * 48 * @see SecretKey 49 * @see javax.crypto.spec.DESKeySpec 50 * @see javax.crypto.spec.DESedeKeySpec 51 * @since 1.4 52 */ 53 54 public abstract class SecretKeyFactorySpi { 55 56 /** 57 * Generates a <code>SecretKey</code> object from the 58 * provided key specification (key material). 59 * 60 * @param keySpec the specification (key material) of the secret key 61 * 62 * @return the secret key 63 * 64 * @exception InvalidKeySpecException if the given key specification 65 * is inappropriate for this secret-key factory to produce a secret key. 66 */ 67 protected abstract SecretKey engineGenerateSecret(KeySpec keySpec) 68 throws InvalidKeySpecException; 69 70 /** 71 * Returns a specification (key material) of the given key 72 * object in the requested format. 73 * 74 * @param key the key 75 * 76 * @param keySpec the requested format in which the key material shall be 77 * returned 78 * 79 * @return the underlying key specification (key material) in the 80 * requested format 81 * 82 * @exception InvalidKeySpecException if the requested key specification is 83 * inappropriate for the given key (e.g., the algorithms associated with 84 * <code>key</code> and <code>keySpec</code> do not match, or 85 * <code>key</code> references a key on a cryptographic hardware device 86 * whereas <code>keySpec</code> is the specification of a software-based 87 * key), or the given key cannot be dealt with 88 * (e.g., the given key has an algorithm or format not supported by this 89 * secret-key factory). 90 */ 91 protected abstract KeySpec engineGetKeySpec(SecretKey key, Class keySpec) 92 throws InvalidKeySpecException; 93 94 /** 95 * Translates a key object, whose provider may be unknown or 96 * potentially untrusted, into a corresponding key object of this 97 * secret-key factory. 98 * 99 * @param key the key whose provider is unknown or untrusted 100 * 101 * @return the translated key 102 * 103 * @exception InvalidKeyException if the given key cannot be processed 104 * by this secret-key factory. 105 */ 106 protected abstract SecretKey engineTranslateKey(SecretKey key) 107 throws InvalidKeyException; 108 } 109