J. Duke | 319a3b9 | 2007-12-01 00:00:00 +0000 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright 1996-2003 Sun Microsystems, Inc. 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. Sun designates this |
| 8 | * particular file as subject to the "Classpath" exception as provided |
| 9 | * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
| 22 | * CA 95054 USA or visit www.sun.com if you need additional information or |
| 23 | * have any questions. |
| 24 | */ |
| 25 | |
| 26 | package sun.security.x509; |
| 27 | |
| 28 | import java.io.IOException; |
| 29 | import java.math.BigInteger; |
| 30 | import java.security.*; |
| 31 | import java.security.interfaces.DSAParams; |
| 32 | |
| 33 | import sun.security.util.*; |
| 34 | |
| 35 | |
| 36 | /** |
| 37 | * This class identifies DSS/DSA Algorithm variants, which are distinguished |
| 38 | * by using different algorithm parameters <em>P, Q, G</em>. It uses the |
| 39 | * NIST/IETF standard DER encoding. These are used to implement the Digital |
| 40 | * Signature Standard (DSS), FIPS 186. |
| 41 | * |
| 42 | * <P><em><b>NOTE:</b> DSS/DSA Algorithm IDs may be created without these |
| 43 | * parameters. Use of DSS/DSA in modes where parameters are |
| 44 | * either implicit (e.g. a default applicable to a site or a larger scope), |
| 45 | * or are derived from some Certificate Authority's DSS certificate, is |
| 46 | * not supported directly. The application is responsible for creating a key |
| 47 | * containing the required parameters prior to using the key in cryptographic |
| 48 | * operations. The follwoing is an example of how this may be done assuming |
| 49 | * that we have a certificate called <code>currentCert</code> which doesn't |
| 50 | * contain DSS/DSA parameters and we need to derive DSS/DSA parameters |
| 51 | * from a CA's certificate called <code>caCert</code>. |
| 52 | * <p> |
| 53 | * <code><pre> |
| 54 | * // key containing parameters to use |
| 55 | * DSAPublicKey cAKey = (DSAPublicKey)(caCert.getPublicKey()); |
| 56 | * // key without parameters |
| 57 | * DSAPublicKey nullParamsKey = (DSAPublicKey)(currentCert.getPublicKey()); |
| 58 | * |
| 59 | * DSAParams cAKeyParams = cAKey.getParams(); |
| 60 | * KeyFactory kf = KeyFactory.getInstance("DSA"); |
| 61 | * DSAPublicKeySpec ks = new DSAPublicKeySpec(nullParamsKey.getY(), |
| 62 | * cAKeyParams.getP(), |
| 63 | * cAKeyParams.getQ(), |
| 64 | * cAKeyParams.getG()); |
| 65 | * DSAPublicKey usableKey = kf.generatePublic(ks); |
| 66 | * </pre></code> |
| 67 | * |
| 68 | * @see java.security.interfaces.DSAParams |
| 69 | * @see java.security.interfaces.DSAPublicKey |
| 70 | * @see java.security.KeyFactory |
| 71 | * @see java.security.spec.DSAPublicKeySpec |
| 72 | * |
| 73 | * @author David Brownell |
| 74 | */ |
| 75 | public final |
| 76 | class AlgIdDSA extends AlgorithmId implements DSAParams |
| 77 | { |
| 78 | |
| 79 | private static final long serialVersionUID = 3437177836797504046L; |
| 80 | |
| 81 | /* |
| 82 | * The three unsigned integer parameters. |
| 83 | */ |
| 84 | private BigInteger p , q, g; |
| 85 | |
| 86 | /** Returns the DSS/DSA parameter "P" */ |
| 87 | public BigInteger getP () { return p; } |
| 88 | |
| 89 | /** Returns the DSS/DSA parameter "Q" */ |
| 90 | public BigInteger getQ () { return q; } |
| 91 | |
| 92 | /** Returns the DSS/DSA parameter "G" */ |
| 93 | public BigInteger getG () { return g; } |
| 94 | |
| 95 | /** |
| 96 | * Default constructor. The OID and parameters must be |
| 97 | * deserialized before this algorithm ID is used. |
| 98 | */ |
| 99 | // XXX deprecated for general use |
| 100 | public AlgIdDSA () {} |
| 101 | |
| 102 | AlgIdDSA (DerValue val) throws IOException |
| 103 | { super(val.getOID()); } |
| 104 | |
| 105 | /** |
| 106 | * Construct an AlgIdDSA from an X.509 encoded byte array. |
| 107 | */ |
| 108 | public AlgIdDSA (byte[] encodedAlg) throws IOException |
| 109 | { super (new DerValue(encodedAlg).getOID()); } |
| 110 | |
| 111 | /** |
| 112 | * Constructs a DSS/DSA Algorithm ID from unsigned integers that |
| 113 | * define the algorithm parameters. Those integers are encoded |
| 114 | * as big-endian byte arrays. |
| 115 | * |
| 116 | * @param p the DSS/DSA paramter "P" |
| 117 | * @param q the DSS/DSA paramter "Q" |
| 118 | * @param g the DSS/DSA paramter "G" |
| 119 | */ |
| 120 | public AlgIdDSA (byte p [], byte q [], byte g []) |
| 121 | throws IOException |
| 122 | { |
| 123 | this (new BigInteger (1, p), |
| 124 | new BigInteger (1, q), |
| 125 | new BigInteger (1, g)); |
| 126 | } |
| 127 | |
| 128 | /** |
| 129 | * Constructs a DSS/DSA Algorithm ID from numeric parameters. |
| 130 | * If all three are null, then the parameters portion of the algorithm id |
| 131 | * is set to null. See note in header regarding use. |
| 132 | * |
| 133 | * @param p the DSS/DSA paramter "P" |
| 134 | * @param q the DSS/DSA paramter "Q" |
| 135 | * @param g the DSS/DSA paramter "G" |
| 136 | */ |
| 137 | public AlgIdDSA (BigInteger p, BigInteger q, BigInteger g) |
| 138 | { |
| 139 | super (DSA_oid); |
| 140 | |
| 141 | if (p != null || q != null || g != null) { |
| 142 | if (p == null || q == null || g == null) |
| 143 | throw new ProviderException("Invalid parameters for DSS/DSA" + |
| 144 | " Algorithm ID"); |
| 145 | try { |
| 146 | this.p = p; |
| 147 | this.q = q; |
| 148 | this.g = g; |
| 149 | initializeParams (); |
| 150 | |
| 151 | } catch (IOException e) { |
| 152 | /* this should not happen */ |
| 153 | throw new ProviderException ("Construct DSS/DSA Algorithm ID"); |
| 154 | } |
| 155 | } |
| 156 | } |
| 157 | |
| 158 | /** |
| 159 | * Returns "DSA", indicating the Digital Signature Algorithm (DSA) as |
| 160 | * defined by the Digital Signature Standard (DSS), FIPS 186. |
| 161 | */ |
| 162 | public String getName () |
| 163 | { return "DSA"; } |
| 164 | |
| 165 | |
| 166 | /* |
| 167 | * For algorithm IDs which haven't been created from a DER encoded |
| 168 | * value, "params" must be created. |
| 169 | */ |
| 170 | private void initializeParams () |
| 171 | throws IOException |
| 172 | { |
| 173 | DerOutputStream out = new DerOutputStream (); |
| 174 | |
| 175 | out.putInteger(p); |
| 176 | out.putInteger(q); |
| 177 | out.putInteger(g); |
| 178 | params = new DerValue (DerValue.tag_Sequence,out.toByteArray ()); |
| 179 | } |
| 180 | |
| 181 | /** |
| 182 | * Parses algorithm parameters P, Q, and G. They're found |
| 183 | * in the "params" member, which never needs to be changed. |
| 184 | */ |
| 185 | protected void decodeParams () |
| 186 | throws IOException |
| 187 | { |
| 188 | if (params == null) |
| 189 | throw new IOException("DSA alg params are null"); |
| 190 | if (params.tag != DerValue.tag_Sequence) |
| 191 | throw new IOException("DSA alg parsing error"); |
| 192 | |
| 193 | params.data.reset (); |
| 194 | |
| 195 | this.p = params.data.getBigInteger(); |
| 196 | this.q = params.data.getBigInteger(); |
| 197 | this.g = params.data.getBigInteger(); |
| 198 | |
| 199 | if (params.data.available () != 0) |
| 200 | throw new IOException ("AlgIdDSA params, extra="+ |
| 201 | params.data.available ()); |
| 202 | } |
| 203 | |
| 204 | |
| 205 | /* |
| 206 | * Returns a formatted string describing the parameters. |
| 207 | */ |
| 208 | public String toString () |
| 209 | { return paramsToString (); } |
| 210 | |
| 211 | /* |
| 212 | * Returns a string describing the parameters. |
| 213 | */ |
| 214 | protected String paramsToString () |
| 215 | { |
| 216 | if (params == null) |
| 217 | return " null\n"; |
| 218 | else |
| 219 | return |
| 220 | "\n p:\n" + Debug.toHexString(p) + |
| 221 | "\n q:\n" + Debug.toHexString(q) + |
| 222 | "\n g:\n" + Debug.toHexString(g) + |
| 223 | "\n"; |
| 224 | } |
| 225 | } |