libjava/java/security/cert/PKIXCertPathChecker.java

   1 /* PKIXCertPathChecker.java -- checks X.509 certificate paths.
   2    Copyright (C) 2003 Free Software Foundation, Inc.
   3
   4 This file is part of GNU Classpath.
   5
   6 GNU Classpath is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2, or (at your option)
   9 any later version.
  10
  11 GNU Classpath is distributed in the hope that it will be useful, but
  12 WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14 General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GNU Classpath; see the file COPYING.  If not, write to the
  18 Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  19 02111-1307 USA.
  20
  21 Linking this library statically or dynamically with other modules is
  22 making a combined work based on this library.  Thus, the terms and
  23 conditions of the GNU General Public License cover the whole
  24 combination.
  25
  26 As a special exception, the copyright holders of this library give you
  27 permission to link this library with independent modules to produce an
  28 executable, regardless of the license terms of these independent
  29 modules, and to copy and distribute the resulting executable under
  30 terms of your choice, provided that you also meet, for each linked
  31 independent module, the terms and conditions of the license of that
  32 module.  An independent module is a module which is not derived from
  33 or based on this library.  If you modify this library, you may extend
  34 this exception to your version of the library, but you are not
  35 obligated to do so.  If you do not wish to do so, delete this
  36 exception statement from your version. */
  37
  38
  39 package java.security.cert;
  40
  41 import java.util.Collection;
  42 import java.util.Set;
  43
  44 /**
  45  * A validator for X.509 certificates when approving certificate chains.
  46  *
  47  * <p>Concrete subclasses can be passed to the {@link
  48  * PKIXParameters#setCertPathCheckers(java.util.List)} and {@link
  49  * PKIXParameters#addCertPathChecker(java.security.cert.PKIXCertPathChecker}
  50  * methods, which are then used to set up PKIX certificate chain
  51  * builders or validators. These classes then call the {@link
  52  * #check(java.security.cert.Certificate,java.util.Collection)} method
  53  * of this class, performing whatever checks on the certificate,
  54  * throwing an exception if any check fails.
  55  *
  56  * <p>Subclasses of this must be able to perform their checks in the
  57  * backward direction -- from the most-trusted certificate to the target
  58  * -- and may optionally support forward checking -- from the target to
  59  * the most-trusted certificate.
  60  *
  61  * @see PKIXParameters
  62  */
  63 public abstract class PKIXCertPathChecker implements Cloneable
  64 {
  65
  66   // Constructor.
  67   // ------------------------------------------------------------------------
  68
  69   /** Default constructor. */
  70   protected PKIXCertPathChecker()
  71   {
  72     super();
  73   }
  74
  75   // Cloneable interface.
  76   // ------------------------------------------------------------------------
  77
  78   public Object clone()
  79   {
  80     try
  81       {
  82         return super.clone();
  83       }
  84     catch (CloneNotSupportedException cnse)
  85       {
  86         throw new InternalError(cnse.getMessage());
  87       }
  88   }
  89
  90   // Abstract methods.
  91   // ------------------------------------------------------------------------
  92
  93   /**
  94    * Initialize this PKIXCertPathChecker. If subclasses support forward
  95    * checking, a value of true can be passed to this method, and
  96    * certificates can be validated from the target certificate to the
  97    * most-trusted certifcate.
  98    *
  99    * @param forward The direction of this PKIXCertPathChecker.
 100    * @throws CertPathValidatorException If <i>forward</i> is true and
 101    *         this class does not support forward checking.
 102    */
 103   public abstract void init(boolean forward) throws CertPathValidatorException;
 104
 105   /**
 106    * Returns whether or not this class supports forward checking.
 107    *
 108    * @return Whether or not this class supports forward checking.
 109    */
 110   public abstract boolean isForwardCheckingSupported();
 111
 112   /**
 113    * Returns an immutable set of X.509 extension object identifiers (OIDs)
 114    * supported by this PKIXCertPathChecker.
 115    *
 116    * @return An immutable set of Strings of the supported X.509 OIDs, or
 117    *         null if no extensions are supported.
 118    */
 119   public abstract Set getSupportedExtensions();
 120
 121   /**
 122    * Checks a certificate, removing any critical extensions that are
 123    * resolved in this check.
 124    *
 125    * @param cert               The certificate to check.
 126    * @param unresolvedCritExts The (mutable) collection of as-of-yet
 127    *        unresolved critical extensions, as OID strings.
 128    * @throws CertPathValidatorException If this certificate fails this
 129    *         check.
 130    */
 131   public abstract void check(Certificate cert, Collection unresolvedCritExts)
 132   throws CertPathValidatorException;
 133 }