001/* CertPathValidator -- validates certificate paths.
002   Copyright (C) 2003, 2004  Free Software Foundation, Inc.
003
004This file is part of GNU Classpath.
005
006GNU Classpath is free software; you can redistribute it and/or modify
007it under the terms of the GNU General Public License as published by
008the Free Software Foundation; either version 2, or (at your option)
009any later version.
010
011GNU Classpath is distributed in the hope that it will be useful, but
012WITHOUT ANY WARRANTY; without even the implied warranty of
013MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
014General Public License for more details.
015
016You should have received a copy of the GNU General Public License
017along with GNU Classpath; see the file COPYING.  If not, write to the
018Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
01902110-1301 USA.
020
021Linking this library statically or dynamically with other modules is
022making a combined work based on this library.  Thus, the terms and
023conditions of the GNU General Public License cover the whole
024combination.
025
026As a special exception, the copyright holders of this library give you
027permission to link this library with independent modules to produce an
028executable, regardless of the license terms of these independent
029modules, and to copy and distribute the resulting executable under
030terms of your choice, provided that you also meet, for each linked
031independent module, the terms and conditions of the license of that
032module.  An independent module is a module which is not derived from
033or based on this library.  If you modify this library, you may extend
034this exception to your version of the library, but you are not
035obligated to do so.  If you do not wish to do so, delete this
036exception statement from your version. */
037
038
039package java.security.cert;
040
041import gnu.java.lang.CPStringBuilder;
042
043import gnu.java.security.Engine;
044
045import java.lang.reflect.InvocationTargetException;
046import java.security.AccessController;
047import java.security.InvalidAlgorithmParameterException;
048import java.security.NoSuchAlgorithmException;
049import java.security.NoSuchProviderException;
050import java.security.PrivilegedAction;
051import java.security.Provider;
052import java.security.Security;
053
054/**
055 * Generic interface to classes that validate certificate paths.
056 *
057 * <p>Using this class is similar to all the provider-based security
058 * classes; the method of interest, {@link
059 * #validate(java.security.cert.CertPath,java.security.cert.CertPathParameters)},
060 * which takes provider-specific implementations of {@link
061 * CertPathParameters}, and return provider-specific implementations of
062 * {@link CertPathValidatorResult}.
063 *
064 * @since JDK 1.4
065 * @see CertPath
066 */
067public class CertPathValidator {
068
069  // Constants and fields.
070  // ------------------------------------------------------------------------
071
072  /** Service name for CertPathValidator. */
073  private static final String CERT_PATH_VALIDATOR = "CertPathValidator";
074
075  /** The underlying implementation. */
076  private final CertPathValidatorSpi validatorSpi;
077
078  /** The provider of this implementation. */
079  private final Provider provider;
080
081  /** The algorithm's name. */
082  private final String algorithm;
083
084  // Constructor.
085  // ------------------------------------------------------------------------
086
087  /**
088   * Creates a new CertPathValidator.
089   *
090   * @param validatorSpi The underlying implementation.
091   * @param provider     The provider of the implementation.
092   * @param algorithm    The algorithm name.
093   */
094  protected CertPathValidator(CertPathValidatorSpi validatorSpi,
095                              Provider provider, String algorithm)
096  {
097    this.validatorSpi = validatorSpi;
098    this.provider = provider;
099    this.algorithm = algorithm;
100  }
101
102  // Class methods.
103  // ------------------------------------------------------------------------
104
105  /**
106   * Returns the default validator type.
107   *
108   * <p>This value may be set at run-time via the security property
109   * "certpathvalidator.type", or the value "PKIX" if this property is
110   * not set.
111   *
112   * @return The default validator type.
113   */
114  public static synchronized String getDefaultType() {
115    String type = (String) AccessController.doPrivileged(
116      new PrivilegedAction()
117        {
118          public Object run()
119          {
120            return Security.getProperty("certpathvalidator.type");
121          }
122        }
123    );
124    if (type == null)
125      type = "PKIX";
126    return type;
127  }
128
129  /**
130   * Returns an instance of the given validator from the first provider that
131   * implements it.
132   *
133   * @param algorithm The name of the algorithm to get.
134   * @return The new instance.
135   * @throws NoSuchAlgorithmException If no installed provider implements the
136   *           requested algorithm.
137   * @throws IllegalArgumentException if <code>algorithm</code> is
138   *           <code>null</code> or is an empty string.
139   */
140  public static CertPathValidator getInstance(String algorithm)
141    throws NoSuchAlgorithmException
142  {
143    Provider[] p = Security.getProviders();
144    NoSuchAlgorithmException lastException = null;
145    for (int i = 0; i < p.length; i++)
146      try
147        {
148          return getInstance(algorithm, p[i]);
149        }
150      catch (NoSuchAlgorithmException x)
151        {
152          lastException = x;
153        }
154    if (lastException != null)
155      throw lastException;
156    throw new NoSuchAlgorithmException(algorithm);
157  }
158
159  /**
160   * Returns an instance of the given validator from the named provider.
161   *
162   * @param algorithm The name of the algorithm to get.
163   * @param provider The name of the provider from which to get the
164   *          implementation.
165   * @return The new instance.
166   * @throws NoSuchAlgorithmException If the named provider does not implement
167   *           the algorithm.
168   * @throws NoSuchProviderException If no provider named <i>provider</i> is
169   *           installed.
170   * @throws IllegalArgumentException if either <code>algorithm</code> or
171   *           <code>provider</code> is <code>null</code>, or if
172   *           <code>algorithm</code> is an empty string.
173   */
174  public static CertPathValidator getInstance(String algorithm, String provider)
175      throws NoSuchAlgorithmException, NoSuchProviderException
176  {
177    if (provider == null)
178      throw new IllegalArgumentException("provider MUST NOT be null");
179    Provider p = Security.getProvider(provider);
180    if (p == null)
181      throw new NoSuchProviderException(provider);
182    return getInstance(algorithm, p);
183  }
184
185  /**
186   * Returns an instance of the given validator from the given provider.
187   *
188   * @param algorithm The name of the algorithm to get.
189   * @param provider The provider from which to get the implementation.
190   * @return The new instance.
191   * @throws NoSuchAlgorithmException If the provider does not implement the
192   *           algorithm.
193   * @throws IllegalArgumentException if either <code>algorithm</code> or
194   *           <code>provider</code> is <code>null</code>, or if
195   *           <code>algorithm</code> is an empty string.
196   */
197  public static CertPathValidator getInstance(String algorithm,
198                                              Provider provider)
199    throws NoSuchAlgorithmException
200  {
201    CPStringBuilder sb = new CPStringBuilder("CertPathValidator for algorithm [")
202        .append(algorithm).append("] from provider[")
203        .append(provider).append("] could not be created");
204    Throwable cause;
205    try
206      {
207        Object spi = Engine.getInstance(CERT_PATH_VALIDATOR, algorithm, provider);
208        return new CertPathValidator((CertPathValidatorSpi) spi, provider, algorithm);
209      }
210    catch (InvocationTargetException x)
211      {
212        cause = x.getCause();
213        if (cause instanceof NoSuchAlgorithmException)
214          throw (NoSuchAlgorithmException) cause;
215        if (cause == null)
216          cause = x;
217      }
218    catch (ClassCastException x)
219      {
220        cause = x;
221      }
222    NoSuchAlgorithmException x = new NoSuchAlgorithmException(sb.toString());
223    x.initCause(cause);
224    throw x;
225  }
226
227  /**
228   * Return the name of this validator.
229   *
230   * @return This validator's name.
231   */
232  public final String getAlgorithm()
233  {
234    return algorithm;
235  }
236
237  /**
238   * Return the provider of this implementation.
239   *
240   * @return The provider.
241   */
242  public final Provider getProvider()
243  {
244    return provider;
245  }
246
247  /**
248   * Attempt to validate a certificate path.
249   *
250   * @param certPath The path to validate.
251   * @param params   The algorithm-specific parameters.
252   * @return The result of this validation attempt.
253   * @throws CertPathValidatorException If the certificate path cannot
254   * be validated.
255   * @throws InvalidAlgorithmParameterException If this implementation
256   * rejects the specified parameters.
257   */
258  public final CertPathValidatorResult validate(CertPath certPath,
259                                                CertPathParameters params)
260    throws CertPathValidatorException, InvalidAlgorithmParameterException
261  {
262    return validatorSpi.engineValidate(certPath, params);
263  }
264}