| Frames | No Frames |
1: /* GnuDHKey.java -- 2: Copyright (C) 2003, 2006 Free Software Foundation, Inc. 3: 4: This file is a 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 of the License, or (at 9: your option) 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; if not, write to the Free Software 18: Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 19: 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 gnu.javax.crypto.key.dh; 40: 41: import gnu.java.security.Registry; 42: import gnu.java.security.action.GetPropertyAction; 43: import gnu.java.security.util.FormatUtil; 44: 45: import java.math.BigInteger; 46: import java.security.AccessController; 47: import java.security.Key; 48: 49: import javax.crypto.interfaces.DHKey; 50: import javax.crypto.spec.DHParameterSpec; 51: 52: /** 53: * A base asbtract class for both public and private Diffie-Hellman keys. It 54: * encapsulates the two DH numbers: <code>p</code>, and <code>g</code>. 55: * <p> 56: * According to the JDK, cryptographic <i>Keys</i> all have a <i>format</i>. 57: * The format used in this implementation is called <i>Raw</i>, and basically 58: * consists of the raw byte sequences of algorithm parameters. The exact order 59: * of the byte sequences and the implementation details are given in each of the 60: * relevant <code>getEncoded()</code> methods of each of the private and 61: * public keys. 62: * <p> 63: * Reference: 64: * <ol> 65: * <li><a href="http://www.ietf.org/rfc/rfc2631.txt">Diffie-Hellman Key 66: * Agreement Method</a><br> 67: * Eric Rescorla.</li> 68: * </ol> 69: */ 70: public abstract class GnuDHKey 71: implements Key, DHKey 72: { 73: /** The public prime q. A prime divisor of p-1. */ 74: protected BigInteger q; 75: /** The public prime p. */ 76: protected BigInteger p; 77: /** The generator g. */ 78: protected BigInteger g; 79: /** 80: * Identifier of the default encoding format to use when externalizing the key 81: * material. 82: */ 83: protected final int defaultFormat; 84: /** String representation of this key. Cached for speed. */ 85: private transient String str; 86: 87: /** 88: * Trivial protected constructor. 89: * 90: * @param defaultFormat the identifier of the encoding format to use by 91: * default when externalizing the key. 92: * @param q a prime divisor of p-1. 93: * @param p the public prime. 94: * @param g the generator of the group. 95: */ 96: protected GnuDHKey(int defaultFormat, BigInteger q, BigInteger p, BigInteger g) 97: { 98: super(); 99: 100: this.defaultFormat = defaultFormat <= 0 ? Registry.RAW_ENCODING_ID 101: : defaultFormat; 102: this.q = q; 103: this.p = p; 104: this.g = g; 105: } 106: 107: public DHParameterSpec getParams() 108: { 109: if (q == null) 110: return new DHParameterSpec(p, g); 111: return new DHParameterSpec(p, g, q.bitLength()); 112: } 113: 114: public String getAlgorithm() 115: { 116: return Registry.DH_KPG; 117: } 118: 119: /** @deprecated see getEncoded(int). */ 120: public byte[] getEncoded() 121: { 122: return getEncoded(defaultFormat); 123: } 124: 125: public String getFormat() 126: { 127: return FormatUtil.getEncodingShortName(defaultFormat); 128: } 129: 130: public BigInteger getQ() 131: { 132: return q; 133: } 134: 135: /** 136: * Returns <code>true</code> if the designated object is an instance of 137: * {@link DHKey} and has the same Diffie-Hellman parameter values as this one. 138: * 139: * @param obj the other non-null DH key to compare to. 140: * @return <code>true</code> if the designated object is of the same type 141: * and value as this one. 142: */ 143: public boolean equals(Object obj) 144: { 145: if (obj == null) 146: return false; 147: if (! (obj instanceof DHKey)) 148: return false; 149: DHKey that = (DHKey) obj; 150: return p.equals(that.getParams().getP()) 151: && g.equals(that.getParams().getG()); 152: } 153: 154: public String toString() 155: { 156: if (str == null) 157: { 158: String ls = (String) AccessController.doPrivileged 159: (new GetPropertyAction("line.separator")); 160: StringBuilder sb = new StringBuilder(ls) 161: .append("defaultFormat=").append(defaultFormat).append(",").append(ls); 162: if (q == null) 163: sb.append("q=null,"); 164: else 165: sb.append("q=0x").append(q.toString(16)).append(","); 166: sb.append(ls).append("p=0x").append(p.toString(16)).append(",").append(ls) 167: .append("g=0x").append(g.toString(16)); 168: str = sb.toString(); 169: } 170: return str; 171: } 172: 173: public abstract byte[] getEncoded(int format); 174: }