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Diffstat (limited to 'libjava/classpath/gnu/java/security/key/dss/DSSKey.java')
-rw-r--r-- | libjava/classpath/gnu/java/security/key/dss/DSSKey.java | 213 |
1 files changed, 213 insertions, 0 deletions
diff --git a/libjava/classpath/gnu/java/security/key/dss/DSSKey.java b/libjava/classpath/gnu/java/security/key/dss/DSSKey.java new file mode 100644 index 000000000..49f229f7b --- /dev/null +++ b/libjava/classpath/gnu/java/security/key/dss/DSSKey.java @@ -0,0 +1,213 @@ +/* DSSKey.java -- + Copyright 2001, 2002, 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.java.security.key.dss; + +import gnu.java.lang.CPStringBuilder; + +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 java.security.interfaces.DSAKey; +import java.security.interfaces.DSAParams; +import java.security.spec.DSAParameterSpec; + +/** + * A base asbtract class for both public and private DSS (Digital Signature + * Standard) keys. It encapsulates the three DSS numbers: <code>p</code>, + * <code>q</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> + * <b>IMPORTANT</b>: Under certain circumstances (e.g. in an X.509 certificate + * with inherited AlgorithmIdentifier's parameters of a SubjectPublicKeyInfo + * element) these three MPIs may be <code>null</code>. + * + * @see DSSPrivateKey#getEncoded + * @see DSSPublicKey#getEncoded + */ +public abstract class DSSKey + implements Key, DSAKey +{ + /** + * A prime modulus, where + * <code>2<sup>L-1</sup> < p < 2<sup>L</sup></code> for + * <code>512 <= L <= 1024</code> and <code>L</code> a multiple of + * <code>64</code>. + */ + protected final BigInteger p; + + /** + * A prime divisor of <code>p - 1</code>, where + * <code>2<sup>159</sup> < q + * < 2<sup>160</sup></code>. + */ + protected final BigInteger q; + + /** + * <code>g = h<sup>(p-1)</sup>/q mod p</code>, where <code>h</code> is + * any integer with <code>1 < h < p - 1</code> such that <code>h<sup> + * (p-1)</sup>/q mod p > 1</code> (<code>g</code> + * has order <code>q mod p + * </code>). + */ + protected final 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 p the DSS parameter <code>p</code>. + * @param q the DSS parameter <code>q</code>. + * @param g the DSS parameter <code>g</code>. + */ + protected DSSKey(int defaultFormat, BigInteger p, BigInteger q, BigInteger g) + { + super(); + + this.defaultFormat = defaultFormat <= 0 ? Registry.RAW_ENCODING_ID + : defaultFormat; + this.p = p; + this.q = q; + this.g = g; + } + + public DSAParams getParams() + { + return new DSAParameterSpec(p, q, g); + } + + public String getAlgorithm() + { + return Registry.DSS_KPG; + } + + /** @deprecated see getEncoded(int). */ + public byte[] getEncoded() + { + return getEncoded(defaultFormat); + } + + public String getFormat() + { + return FormatUtil.getEncodingShortName(defaultFormat); + } + + /** + * Returns <code>true</code> if the designated object is an instance of + * {@link DSAKey} and has the same DSS (Digital Signature Standard) parameter + * values as this one. + * <p> + * Always returns <code>false</code> if the MPIs of this key are + * <i>inherited</i>. This may be the case when the key is re-constructed from + * an X.509 certificate with absent or NULL AlgorithmIdentifier's parameters + * field. + * + * @param obj the other non-null DSS 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 (hasInheritedParameters()) + return false; + + if (obj == null) + return false; + + if (! (obj instanceof DSAKey)) + return false; + + DSAKey that = (DSAKey) obj; + return p.equals(that.getParams().getP()) + && q.equals(that.getParams().getQ()) + && g.equals(that.getParams().getG()); + } + + public String toString() + { + if (str == null) + { + String ls = (String) AccessController.doPrivileged(new GetPropertyAction("line.separator")); + CPStringBuilder sb = new CPStringBuilder(ls) + .append("defaultFormat=").append(defaultFormat).append(",") + .append(ls); + if (hasInheritedParameters()) + sb.append("p=inherited,").append(ls) + .append("q=inherited,").append(ls) + .append("g=inherited"); + else + sb.append("p=0x").append(p.toString(16)).append(",").append(ls) + .append("q=0x").append(q.toString(16)).append(",").append(ls) + .append("g=0x").append(g.toString(16)); + str = sb.toString(); + } + return str; + } + + public abstract byte[] getEncoded(int format); + + /** + * @return <code>true</code> if <code>p</code>, <code>q</code> and + * <code>g</code> are all <code>null</code>. Returns + * <code>false</code> otherwise. + */ + public boolean hasInheritedParameters() + { + return p == null && q == null && g == null; + } +} |