| /* GnuDHKey.java -- |
| Copyright (C) 2003, 2006 Free Software Foundation, Inc. |
| |
| This file is a part of GNU Classpath. |
| |
| GNU Classpath is free software; you can redistribute it and/or modify |
| it under the terms of the GNU General Public License as published by |
| the Free Software Foundation; either version 2 of the License, or (at |
| your option) any later version. |
| |
| GNU Classpath is distributed in the hope that it will be useful, but |
| WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| General Public License for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with GNU Classpath; if not, write to the Free Software |
| Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 |
| USA |
| |
| Linking this library statically or dynamically with other modules is |
| making a combined work based on this library. Thus, the terms and |
| conditions of the GNU General Public License cover the whole |
| combination. |
| |
| As a special exception, the copyright holders of this library give you |
| permission to link this library with independent modules to produce an |
| executable, regardless of the license terms of these independent |
| modules, and to copy and distribute the resulting executable under |
| terms of your choice, provided that you also meet, for each linked |
| independent module, the terms and conditions of the license of that |
| module. An independent module is a module which is not derived from |
| or based on this library. If you modify this library, you may extend |
| this exception to your version of the library, but you are not |
| obligated to do so. If you do not wish to do so, delete this |
| exception statement from your version. */ |
| |
| |
| package gnu.javax.crypto.key.dh; |
| |
| import gnu.java.security.Registry; |
| import gnu.java.security.action.GetPropertyAction; |
| import gnu.java.security.util.FormatUtil; |
| |
| import java.math.BigInteger; |
| import java.security.AccessController; |
| import java.security.Key; |
| |
| import javax.crypto.interfaces.DHKey; |
| import javax.crypto.spec.DHParameterSpec; |
| |
| /** |
| * A base asbtract class for both public and private Diffie-Hellman keys. It |
| * encapsulates the two DH numbers: <code>p</code>, and <code>g</code>. |
| * <p> |
| * According to the JDK, cryptographic <i>Keys</i> all have a <i>format</i>. |
| * The format used in this implementation is called <i>Raw</i>, and basically |
| * consists of the raw byte sequences of algorithm parameters. The exact order |
| * of the byte sequences and the implementation details are given in each of the |
| * relevant <code>getEncoded()</code> methods of each of the private and |
| * public keys. |
| * <p> |
| * Reference: |
| * <ol> |
| * <li><a href="http://www.ietf.org/rfc/rfc2631.txt">Diffie-Hellman Key |
| * Agreement Method</a><br> |
| * Eric Rescorla.</li> |
| * </ol> |
| */ |
| public abstract class GnuDHKey |
| implements Key, DHKey |
| { |
| /** The public prime q. A prime divisor of p-1. */ |
| protected BigInteger q; |
| /** The public prime p. */ |
| protected BigInteger p; |
| /** The generator g. */ |
| protected BigInteger g; |
| /** |
| * Identifier of the default encoding format to use when externalizing the key |
| * material. |
| */ |
| protected final int defaultFormat; |
| /** String representation of this key. Cached for speed. */ |
| private transient String str; |
| |
| /** |
| * Trivial protected constructor. |
| * |
| * @param defaultFormat the identifier of the encoding format to use by |
| * default when externalizing the key. |
| * @param q a prime divisor of p-1. |
| * @param p the public prime. |
| * @param g the generator of the group. |
| */ |
| protected GnuDHKey(int defaultFormat, BigInteger q, BigInteger p, BigInteger g) |
| { |
| super(); |
| |
| this.defaultFormat = defaultFormat <= 0 ? Registry.RAW_ENCODING_ID |
| : defaultFormat; |
| this.q = q; |
| this.p = p; |
| this.g = g; |
| } |
| |
| public DHParameterSpec getParams() |
| { |
| if (q == null) |
| return new DHParameterSpec(p, g); |
| return new DHParameterSpec(p, g, q.bitLength()); |
| } |
| |
| public String getAlgorithm() |
| { |
| return Registry.DH_KPG; |
| } |
| |
| /** @deprecated see getEncoded(int). */ |
| public byte[] getEncoded() |
| { |
| return getEncoded(defaultFormat); |
| } |
| |
| public String getFormat() |
| { |
| return FormatUtil.getEncodingShortName(defaultFormat); |
| } |
| |
| public BigInteger getQ() |
| { |
| return q; |
| } |
| |
| /** |
| * Returns <code>true</code> if the designated object is an instance of |
| * {@link DHKey} and has the same Diffie-Hellman parameter values as this one. |
| * |
| * @param obj the other non-null DH key to compare to. |
| * @return <code>true</code> if the designated object is of the same type |
| * and value as this one. |
| */ |
| public boolean equals(Object obj) |
| { |
| if (obj == null) |
| return false; |
| if (! (obj instanceof DHKey)) |
| return false; |
| DHKey that = (DHKey) obj; |
| return p.equals(that.getParams().getP()) |
| && g.equals(that.getParams().getG()); |
| } |
| |
| public String toString() |
| { |
| if (str == null) |
| { |
| String ls = (String) AccessController.doPrivileged |
| (new GetPropertyAction("line.separator")); |
| StringBuilder sb = new StringBuilder(ls) |
| .append("defaultFormat=").append(defaultFormat).append(",").append(ls); |
| if (q == null) |
| sb.append("q=null,"); |
| else |
| sb.append("q=0x").append(q.toString(16)).append(","); |
| sb.append(ls).append("p=0x").append(p.toString(16)).append(",").append(ls) |
| .append("g=0x").append(g.toString(16)); |
| str = sb.toString(); |
| } |
| return str; |
| } |
| |
| public abstract byte[] getEncoded(int format); |
| } |