001    /* CertificateFactory.java -- Certificate Factory Class
002       Copyright (C) 1999, 2002, 2003, 2004  Free Software Foundation, Inc.
003    
004    This file is part of GNU Classpath.
005    
006    GNU Classpath is free software; you can redistribute it and/or modify
007    it under the terms of the GNU General Public License as published by
008    the Free Software Foundation; either version 2, or (at your option)
009    any later version.
010     
011    GNU Classpath is distributed in the hope that it will be useful, but
012    WITHOUT ANY WARRANTY; without even the implied warranty of
013    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
014    General Public License for more details.
015    
016    You should have received a copy of the GNU General Public License
017    along with GNU Classpath; see the file COPYING.  If not, write to the
018    Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
019    02110-1301 USA.
020    
021    Linking this library statically or dynamically with other modules is
022    making a combined work based on this library.  Thus, the terms and
023    conditions of the GNU General Public License cover the whole
024    combination.
025    
026    As a special exception, the copyright holders of this library give you
027    permission to link this library with independent modules to produce an
028    executable, regardless of the license terms of these independent
029    modules, and to copy and distribute the resulting executable under
030    terms of your choice, provided that you also meet, for each linked
031    independent module, the terms and conditions of the license of that
032    module.  An independent module is a module which is not derived from
033    or based on this library.  If you modify this library, you may extend
034    this exception to your version of the library, but you are not
035    obligated to do so.  If you do not wish to do so, delete this
036    exception statement from your version. */
037    
038    
039    package java.security.cert;
040    
041    import gnu.java.security.Engine;
042    
043    import java.io.InputStream;
044    import java.lang.reflect.InvocationTargetException;
045    import java.security.NoSuchAlgorithmException;
046    import java.security.NoSuchProviderException;
047    import java.security.Provider;
048    import java.security.Security;
049    import java.util.Collection;
050    import java.util.Iterator;
051    import java.util.List;
052    
053    /**
054     * This class implements the CertificateFactory class interface used to
055     * generate certificates, certificate revocation lists (CRLs), and certificate
056     * paths objects from their encoded forms.
057     *
058     * @author Mark Benvenuto
059     * @author Casey Marshall
060     * @since 1.2
061     * @status Fully compatible with JDK 1.4.
062     */
063    public class CertificateFactory
064    {
065    
066      /** The service name for certificate factories. */
067      private static final String CERTIFICATE_FACTORY = "CertificateFactory";
068    
069      private CertificateFactorySpi certFacSpi;
070      private Provider provider;
071      private String type;
072    
073      /**
074       * Creates an instance of CertificateFactory.
075       *
076       * @param certFacSpi The underlying CertificateFactory engine.
077       * @param provider   The provider of this implementation.
078       * @param type       The type of Certificate this factory creates.
079       */
080      protected CertificateFactory(CertificateFactorySpi certFacSpi,
081                                   Provider provider, String type)
082      {
083        this.certFacSpi = certFacSpi;
084        this.provider = provider;
085        this.type = type;
086      }
087    
088      /**
089       * Returns an instance of a <code>CertificateFactory</code> representing the
090       * specified certificate factory type.
091       * 
092       * @param type The type of certificate factory to create.
093       * @return A <code>CertificateFactory</code> of the desired type.
094       * @throws CertificateException If the type of certificate factory is not
095       *           implemented by any installed provider.
096       * @throws IllegalArgumentException if <code>type</code> is
097       *           <code>null</code> or is an empty string.
098       */
099      public static final CertificateFactory getInstance(String type)
100          throws CertificateException
101      {
102        Provider[] p = Security.getProviders();
103        CertificateException lastException = null;
104        for (int i = 0; i < p.length; i++)
105          try
106            {
107              return getInstance(type, p[i]);
108            }
109          catch (CertificateException x)
110            {
111              lastException = x;
112            }
113        if (lastException != null)
114          throw lastException;
115        throw new CertificateException(type);
116      }
117    
118      /**
119       * Returns an instance of a <code>CertificateFactory</code> representing the
120       * specified certificate factory type from the named provider.
121       * 
122       * @param type The type of certificate factory to create.
123       * @param provider The name of the provider to use.
124       * @return A <code>CertificateFactory</code> for the desired type.
125       * @throws CertificateException If the type of certificate is not implemented
126       *           by the named provider.
127       * @throws NoSuchProviderException If the named provider is not installed.
128       * @throws IllegalArgumentException if either <code>type</code> or
129       *           <code>provider</code> is <code>null</code>, or if
130       *           <code>type</code> is an empty string.
131       */
132      public static final CertificateFactory getInstance(String type,
133                                                         String provider) 
134        throws CertificateException, NoSuchProviderException
135      {
136        if (provider == null)
137          throw new IllegalArgumentException("provider MUST NOT be null");
138        Provider p = Security.getProvider(provider);
139        if (p == null)
140          throw new NoSuchProviderException(provider);
141        return getInstance(type, p);
142      }
143    
144      /**
145       * Returns an instance of a <code>CertificateFactory</code> representing the
146       * specified certificate factory type from the designated provider.
147       * 
148       * @param type The type of certificate factory to create.
149       * @param provider The provider from which to get the implementation.
150       * @return A <code>CertificateFactory</code> for the desired type.
151       * @throws CertificateException If the type of certificate is not implemented
152       *           by the provider.
153       * @throws IllegalArgumentException if either <code>type</code> or
154       *           <code>provider</code> is <code>null</code>, or if
155       *           <code>type</code> is an empty string.
156       */
157      public static final CertificateFactory getInstance(String type,
158                                                         Provider provider)
159          throws CertificateException
160      {
161        Throwable cause;
162        try
163          {
164            Object spi = Engine.getInstance(CERTIFICATE_FACTORY, type, provider);
165            return new CertificateFactory((CertificateFactorySpi) spi, provider, type);
166          }
167        catch (ClassCastException x)
168          {
169            cause = x;
170          }
171        catch (InvocationTargetException x)
172          {
173            cause = x.getCause() != null ? x.getCause() : x;
174          }
175        catch (NoSuchAlgorithmException x)
176          {
177            cause = x;
178          }
179        CertificateException x = new CertificateException(type);
180        x.initCause(cause);
181        throw x;
182      }
183    
184      /**
185       * Gets the provider of this implementation.
186       *
187       * @return The provider of this implementation.
188       */
189      public final Provider getProvider()
190      {
191        return provider;
192      }
193    
194      /**
195       * Returns the type of the certificate this factory creates.
196       *
197       * @return A string with the type of certificate
198       */
199      public final String getType()
200      {
201        return type;
202      }
203    
204      /**
205       * Generates a Certificate from the encoded data read
206       * from an InputStream.
207       *
208       * <p>The input stream must contain only one certificate.
209       *
210       * <p>If there exists a specialized certificate class for the
211       * certificate format handled by the certificate factory
212       * then the return Ceritificate should be a typecast of it.
213       * Ex: A X.509 CertificateFactory should return X509Certificate.
214       *
215       * <p>For X.509 certificates, the certificate in inStream must be
216       * DER encoded and supplied in binary or printable (Base64) 
217       * encoding. If the certificate is in Base64 encoding, it must be 
218       * bounded by -----BEGINCERTIFICATE-----, and 
219       * -----END CERTIFICATE-----. 
220       *
221       * @param inStream An input stream containing the certificate data.
222       * @return A certificate initialized from the decoded InputStream data.
223       * @throws CertificateException If an error occurs decoding the
224       *   certificate.
225       */
226      public final Certificate generateCertificate(InputStream inStream)
227        throws CertificateException
228      {
229        return certFacSpi.engineGenerateCertificate(inStream);
230      }
231    
232      /**
233       * Returns a collection of certificates that were read from the 
234       * input stream. It may be empty, have only one, or have 
235       * multiple certificates.
236       *
237       * For a X.509 certificate factory, the stream may contain a
238       * single DER encoded certificate or a PKCS#7 certificate 
239       * chain. This is a PKCS#7 <I>SignedData</I> object with the 
240       * most significant field being <I>certificates</I>. If no 
241       * CRLs are present, then an empty collection is returned.
242             *
243       * @param inStream An input stream containing the certificate data.
244       * @return A collection of certificates initialized from the decoded
245       *   InputStream data.
246       * @throws CertificateException If an error occurs decoding the
247       *   certificates.
248       */
249      public final Collection<? extends Certificate> generateCertificates(InputStream inStream)
250        throws CertificateException
251      {
252        return certFacSpi.engineGenerateCertificates(inStream);
253      }
254    
255      /**
256       * Generates a CRL based on the encoded data read
257       * from the InputStream.
258       *
259       * <p>The input stream must contain only one CRL.
260       *
261       * <p>If there exists a specialized CRL class for the
262       * CRL format handled by the certificate factory
263       * then the return CRL should be a typecast of it.
264       * Ex: A X.509 CertificateFactory should return X509CRL.
265       *
266       * @param inStream An input stream containing the CRL data.
267       * @return A CRL initialized from the decoded InputStream data.
268       * @throws CRLException If an error occurs decoding the CRL.
269       */
270      public final CRL generateCRL(InputStream inStream)
271        throws CRLException
272      {
273        return certFacSpi.engineGenerateCRL(inStream);
274      }
275    
276      /**
277       * <p>Generates CRLs based on the encoded data read
278       * from the InputStream.
279       *
280       * <p>For a X.509 certificate factory, the stream may contain a
281       * single DER encoded CRL or a PKCS#7 CRL set. This is a 
282       * PKCS#7 <I>SignedData</I> object with the most significant 
283       * field being <I>crls</I>. If no CRLs are present, then an
284       * empty collection is returned.
285       *
286       * @param inStream an input stream containing the CRLs.
287       * @return a collection of CRLs initialized from the decoded
288       *    InputStream data.
289       * @throws CRLException If an error occurs decoding the CRLs.
290       */
291      public final Collection<? extends CRL> generateCRLs(InputStream inStream)
292        throws CRLException
293      {
294        return certFacSpi.engineGenerateCRLs( inStream );
295      }
296    
297      /**
298       * Generate a {@link CertPath} and initialize it with data parsed from
299       * the input stream. The default encoding of this factory is used.
300       *
301       * @param inStream The InputStream containing the CertPath data.
302       * @return A CertPath initialized from the input stream data.
303       * @throws CertificateException If an error occurs decoding the
304       * CertPath.
305       */
306      public final CertPath generateCertPath(InputStream inStream)
307        throws CertificateException
308      {
309        return certFacSpi.engineGenerateCertPath(inStream);
310      }
311    
312      /**
313       * Generate a {@link CertPath} and initialize it with data parsed from
314       * the input stream, using the specified encoding.
315       *
316       * @param inStream The InputStream containing the CertPath data.
317       * @param encoding The encoding of the InputStream data.
318       * @return A CertPath initialized from the input stream data.
319       * @throws CertificateException If an error occurs decoding the
320       *   CertPath.
321       */
322      public final CertPath generateCertPath(InputStream inStream, String encoding)
323        throws CertificateException
324      {
325        return certFacSpi.engineGenerateCertPath(inStream, encoding);
326      }
327    
328      /**
329       * Generate a {@link CertPath} and initialize it with the certificates
330       * in the {@link java.util.List} argument.
331       *
332       * @param certificates The list of certificates with which to create
333       *   the CertPath.
334       * @return A CertPath initialized from the certificates.
335       * @throws CertificateException If an error occurs generating the
336       *   CertPath.
337       */
338      public final CertPath generateCertPath(List<? extends Certificate> certificates)
339        throws CertificateException
340      {
341        return certFacSpi.engineGenerateCertPath(certificates);
342      }
343    
344      /**
345       * Returns an Iterator of CertPath encodings supported by this
346       * factory, with the default encoding first. The returned Iterator
347       * cannot be modified.
348       *
349       * @return The Iterator of supported encodings.
350       */
351      public final Iterator<String> getCertPathEncodings()
352      {
353        return certFacSpi.engineGetCertPathEncodings();
354      }
355    } // class CertificateFactory