1: /* KeyFactorySpi.java --- Key Factory Service Provider Interface 2: Copyright (C) 1999, 2004 Free Software Foundation, Inc. 3: 4: This file is part of GNU Classpath. 5: 6: GNU Classpath is free software; you can redistribute it and/or modify 7: it under the terms of the GNU General Public License as published by 8: the Free Software Foundation; either version 2, or (at your option) 9: any later version. 10: 11: GNU Classpath is distributed in the hope that it will be useful, but 12: WITHOUT ANY WARRANTY; without even the implied warranty of 13: MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 14: General Public License for more details. 15: 16: You should have received a copy of the GNU General Public License 17: along with GNU Classpath; see the file COPYING. If not, write to the 18: Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 19: 02110-1301 USA. 20: 21: Linking this library statically or dynamically with other modules is 22: making a combined work based on this library. Thus, the terms and 23: conditions of the GNU General Public License cover the whole 24: combination. 25: 26: As a special exception, the copyright holders of this library give you 27: permission to link this library with independent modules to produce an 28: executable, regardless of the license terms of these independent 29: modules, and to copy and distribute the resulting executable under 30: terms of your choice, provided that you also meet, for each linked 31: independent module, the terms and conditions of the license of that 32: module. An independent module is a module which is not derived from 33: or based on this library. If you modify this library, you may extend 34: this exception to your version of the library, but you are not 35: obligated to do so. If you do not wish to do so, delete this 36: exception statement from your version. */ 37: 38: 39: package java.security; 40: 41: import java.security.spec.InvalidKeySpecException; 42: import java.security.spec.KeySpec; 43: 44: /** 45: * KeyFactorySpi is the Service Provider Interface (SPI) for the 46: * KeyFactory class. This is the interface for providers to 47: * supply to implement a key factory for an algorithm. 48: * 49: * Key factories are used to convert keys (opaque cryptographic 50: * keys of type Key) into key specifications (transparent 51: * representations of the underlying key material). 52: * 53: * Key factories are bi-directional. They allow a key class 54: * to be converted into a key specification (key material) and 55: * back again. 56: * 57: * For example DSA public keys can be specified as 58: * DSAPublicKeySpec or X509EncodedKeySpec. The key factory 59: * translate these key specifications. 60: * 61: * @since JDK 1.2 62: * @author Mark Benvenuto 63: */ 64: public abstract class KeyFactorySpi 65: { 66: /** 67: * Constucts a new KeyFactorySpi. 68: */ 69: public KeyFactorySpi() 70: { 71: } 72: 73: /** 74: * Generates a public key from the provided key specification. 75: * 76: * @param keySpec key specification 77: * 78: * @return the public key 79: * 80: * @throws InvalidKeySpecException invalid key specification for 81: * this key factory to produce a public key 82: */ 83: protected abstract PublicKey engineGeneratePublic(KeySpec keySpec) 84: throws InvalidKeySpecException; 85: 86: 87: /** 88: * Generates a private key from the provided key specification. 89: * 90: * @param keySpec key specification 91: * 92: * @return the private key 93: * 94: * @throws InvalidKeySpecException invalid key specification for 95: * this key factory to produce a private key 96: */ 97: protected abstract PrivateKey engineGeneratePrivate(KeySpec keySpec) 98: throws InvalidKeySpecException; 99: 100: /** 101: * Returns a key specification for the given key. keySpec 102: * identifies the specification class to return the key 103: * material in. 104: * 105: * @param key the key 106: * @param keySpec the specification class to return the 107: * key material in. 108: * 109: * @return the key specification in an instance of the requested 110: * specification class 111: * 112: * @throws InvalidKeySpecException the requested key specification 113: * is inappropriate for this key or the key is 114: * unrecognized. 115: */ 116: protected abstract <T extends KeySpec> T engineGetKeySpec(Key key, 117: Class<T> keySpec) 118: throws InvalidKeySpecException; 119: 120: 121: /** 122: * Translates the key from an unknown or untrusted provider 123: * into a key for this key factory. 124: * 125: * @param key key from an unknown or untrusted provider 126: * 127: * @return the translated key 128: * 129: * @throws InvalidKeyException if the key cannot be 130: * processed by this key factory 131: */ 132: protected abstract Key engineTranslateKey(Key key) 133: throws InvalidKeyException; 134: }