001 /* PKIXCertPathChecker.java -- checks X.509 certificate paths.
002 Copyright (C) 2003 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 java.util.Collection;
042 import java.util.Set;
043
044 /**
045 * A validator for X.509 certificates when approving certificate chains.
046 *
047 * <p>Concrete subclasses can be passed to the {@link
048 * PKIXParameters#setCertPathCheckers(java.util.List)} and {@link
049 * PKIXParameters#addCertPathChecker(java.security.cert.PKIXCertPathChecker)}
050 * methods, which are then used to set up PKIX certificate chain
051 * builders or validators. These classes then call the {@link
052 * #check(java.security.cert.Certificate,java.util.Collection)} method
053 * of this class, performing whatever checks on the certificate,
054 * throwing an exception if any check fails.
055 *
056 * <p>Subclasses of this must be able to perform their checks in the
057 * backward direction -- from the most-trusted certificate to the target
058 * -- and may optionally support forward checking -- from the target to
059 * the most-trusted certificate.
060 *
061 * @see PKIXParameters
062 * @since 1.4
063 */
064 public abstract class PKIXCertPathChecker implements Cloneable
065 {
066
067 // Constructor.
068 // ------------------------------------------------------------------------
069
070 /** Default constructor. */
071 protected PKIXCertPathChecker()
072 {
073 super();
074 }
075
076 // Cloneable interface.
077 // ------------------------------------------------------------------------
078
079 public Object clone()
080 {
081 try
082 {
083 return super.clone();
084 }
085 catch (CloneNotSupportedException cnse)
086 {
087 throw new InternalError(cnse.getMessage());
088 }
089 }
090
091 // Abstract methods.
092 // ------------------------------------------------------------------------
093
094 /**
095 * Initialize this PKIXCertPathChecker. If subclasses support forward
096 * checking, a value of true can be passed to this method, and
097 * certificates can be validated from the target certificate to the
098 * most-trusted certifcate.
099 *
100 * @param forward The direction of this PKIXCertPathChecker.
101 * @throws CertPathValidatorException If <i>forward</i> is true and
102 * this class does not support forward checking.
103 */
104 public abstract void init(boolean forward) throws CertPathValidatorException;
105
106 /**
107 * Returns whether or not this class supports forward checking.
108 *
109 * @return Whether or not this class supports forward checking.
110 */
111 public abstract boolean isForwardCheckingSupported();
112
113 /**
114 * Returns an immutable set of X.509 extension object identifiers (OIDs)
115 * supported by this PKIXCertPathChecker.
116 *
117 * @return An immutable set of Strings of the supported X.509 OIDs, or
118 * null if no extensions are supported.
119 */
120 public abstract Set<String> getSupportedExtensions();
121
122 /**
123 * Checks a certificate, removing any critical extensions that are
124 * resolved in this check.
125 *
126 * @param cert The certificate to check.
127 * @param unresolvedCritExts The (mutable) collection of as-of-yet
128 * unresolved critical extensions, as OID strings.
129 * @throws CertPathValidatorException If this certificate fails this
130 * check.
131 */
132 public abstract void check(Certificate cert, Collection<String> unresolvedCritExts)
133 throws CertPathValidatorException;
134 }