1 /*
   2  * Copyright (c) 2000, 2016, Oracle and/or its affiliates. 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.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 
  26 package java.security.cert;
  27 
  28 import java.security.AccessController;
  29 import java.security.InvalidAlgorithmParameterException;
  30 import java.security.NoSuchAlgorithmException;
  31 import java.security.NoSuchProviderException;
  32 import java.security.PrivilegedAction;
  33 import java.security.Provider;
  34 import java.security.Security;
  35 import sun.security.util.Debug;
  36 
  37 import sun.security.jca.*;
  38 import sun.security.jca.GetInstance.Instance;
  39 
  40 /**
  41  * A class for building certification paths (also known as certificate chains).
  42  * <p>
  43  * This class uses a provider-based architecture.
  44  * To create a {@code CertPathBuilder}, call
  45  * one of the static {@code getInstance} methods, passing in the
  46  * algorithm name of the {@code CertPathBuilder} desired and optionally
  47  * the name of the provider desired.
  48  *
  49  * <p>Once a {@code CertPathBuilder} object has been created, certification
  50  * paths can be constructed by calling the {@link #build build} method and
  51  * passing it an algorithm-specific set of parameters. If successful, the
  52  * result (including the {@code CertPath} that was built) is returned
  53  * in an object that implements the {@code CertPathBuilderResult}
  54  * interface.
  55  *
  56  * <p>The {@link #getRevocationChecker} method allows an application to specify
  57  * additional algorithm-specific parameters and options used by the
  58  * {@code CertPathBuilder} when checking the revocation status of certificates.
  59  * Here is an example demonstrating how it is used with the PKIX algorithm:
  60  *
  61  * <pre>
  62  * CertPathBuilder cpb = CertPathBuilder.getInstance("PKIX");
  63  * PKIXRevocationChecker rc = (PKIXRevocationChecker)cpb.getRevocationChecker();
  64  * rc.setOptions(EnumSet.of(Option.PREFER_CRLS));
  65  * params.addCertPathChecker(rc);
  66  * CertPathBuilderResult cpbr = cpb.build(params);
  67  * </pre>
  68  *
  69  * <p>Every implementation of the Java platform is required to support the
  70  * following standard {@code CertPathBuilder} algorithm:
  71  * <ul>
  72  * <li>{@code PKIX}</li>
  73  * </ul>
  74  * This algorithm is described in the <a href=
  75  * "{@docRoot}/../technotes/guides/security/StandardNames.html#CertPathBuilder">
  76  * CertPathBuilder section</a> of the
  77  * Java Cryptography Architecture Standard Algorithm Name Documentation.
  78  * Consult the release documentation for your implementation to see if any
  79  * other algorithms are supported.
  80  *
  81  * <p>
  82  * <b>Concurrent Access</b>
  83  * <p>
  84  * The static methods of this class are guaranteed to be thread-safe.
  85  * Multiple threads may concurrently invoke the static methods defined in
  86  * this class with no ill effects.
  87  * <p>
  88  * However, this is not true for the non-static methods defined by this class.
  89  * Unless otherwise documented by a specific provider, threads that need to
  90  * access a single {@code CertPathBuilder} instance concurrently should
  91  * synchronize amongst themselves and provide the necessary locking. Multiple
  92  * threads each manipulating a different {@code CertPathBuilder} instance
  93  * need not synchronize.
  94  *
  95  * @see CertPath
  96  *
  97  * @since       1.4
  98  * @author      Sean Mullan
  99  * @author      Yassir Elley
 100  */
 101 public class CertPathBuilder {
 102 
 103     /*
 104      * Constant to lookup in the Security properties file to determine
 105      * the default certpathbuilder type. In the Security properties file,
 106      * the default certpathbuilder type is given as:
 107      * <pre>
 108      * certpathbuilder.type=PKIX
 109      * </pre>
 110      */
 111     private static final String CPB_TYPE = "certpathbuilder.type";
 112     private final CertPathBuilderSpi builderSpi;
 113     private final Provider provider;
 114     private final String algorithm;
 115 
 116     /**
 117      * Creates a {@code CertPathBuilder} object of the given algorithm,
 118      * and encapsulates the given provider implementation (SPI object) in it.
 119      *
 120      * @param builderSpi the provider implementation
 121      * @param provider the provider
 122      * @param algorithm the algorithm name
 123      */
 124     protected CertPathBuilder(CertPathBuilderSpi builderSpi, Provider provider,
 125         String algorithm)
 126     {
 127         this.builderSpi = builderSpi;
 128         this.provider = provider;
 129         this.algorithm = algorithm;
 130     }
 131 
 132     /**
 133      * Returns a {@code CertPathBuilder} object that implements the
 134      * specified algorithm.
 135      *
 136      * <p> This method traverses the list of registered security Providers,
 137      * starting with the most preferred Provider.
 138      * A new CertPathBuilder object encapsulating the
 139      * CertPathBuilderSpi implementation from the first
 140      * Provider that supports the specified algorithm is returned.
 141      *
 142      * <p> Note that the list of registered providers may be retrieved via
 143      * the {@link Security#getProviders() Security.getProviders()} method.
 144      *
 145      * @implNote
 146      * The JDK Reference Implementation additionally uses the
 147      * {@code jdk.security.provider.preferred}
 148      * {@link Security#getProperty(String) Security} property to determine
 149      * the preferred provider order for the specified algorithm. This
 150      * may be different than the order of providers returned by
 151      * {@link Security#getProviders() Security.getProviders()}.
 152      *
 153      * @param algorithm the name of the requested {@code CertPathBuilder}
 154      *  algorithm.  See the CertPathBuilder section in the <a href=
 155      *  "{@docRoot}/../technotes/guides/security/StandardNames.html#CertPathBuilder">
 156      * Java Cryptography Architecture Standard Algorithm Name Documentation</a>
 157      * for information about standard algorithm names.
 158      *
 159      * @return a {@code CertPathBuilder} object that implements the
 160      *          specified algorithm.
 161      *
 162      * @throws NoSuchAlgorithmException if no Provider supports a
 163      *          CertPathBuilderSpi implementation for the
 164      *          specified algorithm.
 165      *
 166      * @see java.security.Provider
 167      */
 168     public static CertPathBuilder getInstance(String algorithm)
 169             throws NoSuchAlgorithmException {
 170         Instance instance = GetInstance.getInstance("CertPathBuilder",
 171             CertPathBuilderSpi.class, algorithm);
 172         return new CertPathBuilder((CertPathBuilderSpi)instance.impl,
 173             instance.provider, algorithm);
 174     }
 175 
 176     /**
 177      * Returns a {@code CertPathBuilder} object that implements the
 178      * specified algorithm.
 179      *
 180      * <p> A new CertPathBuilder object encapsulating the
 181      * CertPathBuilderSpi implementation from the specified provider
 182      * is returned.  The specified provider must be registered
 183      * in the security provider list.
 184      *
 185      * <p> Note that the list of registered providers may be retrieved via
 186      * the {@link Security#getProviders() Security.getProviders()} method.
 187      *
 188      * @param algorithm the name of the requested {@code CertPathBuilder}
 189      *  algorithm.  See the CertPathBuilder section in the <a href=
 190      *  "{@docRoot}/../technotes/guides/security/StandardNames.html#CertPathBuilder">
 191      * Java Cryptography Architecture Standard Algorithm Name Documentation</a>
 192      * for information about standard algorithm names.
 193      *
 194      * @param provider the name of the provider.
 195      *
 196      * @return a {@code CertPathBuilder} object that implements the
 197      *          specified algorithm.
 198      *
 199      * @throws NoSuchAlgorithmException if a CertPathBuilderSpi
 200      *          implementation for the specified algorithm is not
 201      *          available from the specified provider.
 202      *
 203      * @throws NoSuchProviderException if the specified provider is not
 204      *          registered in the security provider list.
 205      *
 206      * @exception IllegalArgumentException if the {@code provider} is
 207      *          null or empty.
 208      *
 209      * @see java.security.Provider
 210      */
 211     public static CertPathBuilder getInstance(String algorithm, String provider)
 212            throws NoSuchAlgorithmException, NoSuchProviderException {
 213         Instance instance = GetInstance.getInstance("CertPathBuilder",
 214             CertPathBuilderSpi.class, algorithm, provider);
 215         return new CertPathBuilder((CertPathBuilderSpi)instance.impl,
 216             instance.provider, algorithm);
 217     }
 218 
 219     /**
 220      * Returns a {@code CertPathBuilder} object that implements the
 221      * specified algorithm.
 222      *
 223      * <p> A new CertPathBuilder object encapsulating the
 224      * CertPathBuilderSpi implementation from the specified Provider
 225      * object is returned.  Note that the specified Provider object
 226      * does not have to be registered in the provider list.
 227      *
 228      * @param algorithm the name of the requested {@code CertPathBuilder}
 229      *  algorithm.  See the CertPathBuilder section in the <a href=
 230      *  "{@docRoot}/../technotes/guides/security/StandardNames.html#CertPathBuilder">
 231      * Java Cryptography Architecture Standard Algorithm Name Documentation</a>
 232      * for information about standard algorithm names.
 233      *
 234      * @param provider the provider.
 235      *
 236      * @return a {@code CertPathBuilder} object that implements the
 237      *          specified algorithm.
 238      *
 239      * @exception NoSuchAlgorithmException if a CertPathBuilderSpi
 240      *          implementation for the specified algorithm is not available
 241      *          from the specified Provider object.
 242      *
 243      * @exception IllegalArgumentException if the {@code provider} is
 244      *          null.
 245      *
 246      * @see java.security.Provider
 247      */
 248     public static CertPathBuilder getInstance(String algorithm,
 249             Provider provider) throws NoSuchAlgorithmException {
 250         Instance instance = GetInstance.getInstance("CertPathBuilder",
 251             CertPathBuilderSpi.class, algorithm, provider);
 252         return new CertPathBuilder((CertPathBuilderSpi)instance.impl,
 253             instance.provider, algorithm);
 254     }
 255 
 256     /**
 257      * Returns the provider of this {@code CertPathBuilder}.
 258      *
 259      * @return the provider of this {@code CertPathBuilder}
 260      */
 261     public final Provider getProvider() {
 262         return this.provider;
 263     }
 264 
 265     /**
 266      * Returns the name of the algorithm of this {@code CertPathBuilder}.
 267      *
 268      * @return the name of the algorithm of this {@code CertPathBuilder}
 269      */
 270     public final String getAlgorithm() {
 271         return this.algorithm;
 272     }
 273 
 274     /**
 275      * Attempts to build a certification path using the specified algorithm
 276      * parameter set.
 277      *
 278      * @param params the algorithm parameters
 279      * @return the result of the build algorithm
 280      * @throws CertPathBuilderException if the builder is unable to construct
 281      *  a certification path that satisfies the specified parameters
 282      * @throws InvalidAlgorithmParameterException if the specified parameters
 283      * are inappropriate for this {@code CertPathBuilder}
 284      */
 285     public final CertPathBuilderResult build(CertPathParameters params)
 286         throws CertPathBuilderException, InvalidAlgorithmParameterException
 287     {
 288         return builderSpi.engineBuild(params);
 289     }
 290 
 291     /**
 292      * Returns the default {@code CertPathBuilder} type as specified by
 293      * the {@code certpathbuilder.type} security property, or the string
 294      * {@literal "PKIX"} if no such property exists.
 295      *
 296      * <p>The default {@code CertPathBuilder} type can be used by
 297      * applications that do not want to use a hard-coded type when calling one
 298      * of the {@code getInstance} methods, and want to provide a default
 299      * type in case a user does not specify its own.
 300      *
 301      * <p>The default {@code CertPathBuilder} type can be changed by
 302      * setting the value of the {@code certpathbuilder.type} security property
 303      * to the desired type.
 304      *
 305      * @see java.security.Security security properties
 306      * @return the default {@code CertPathBuilder} type as specified
 307      * by the {@code certpathbuilder.type} security property, or the string
 308      * {@literal "PKIX"} if no such property exists.
 309      */
 310     public static final String getDefaultType() {
 311         String cpbtype =
 312             AccessController.doPrivileged(new PrivilegedAction<>() {
 313                 public String run() {
 314                     return Security.getProperty(CPB_TYPE);
 315                 }
 316             });
 317         return (cpbtype == null) ? "PKIX" : cpbtype;
 318     }
 319 
 320     /**
 321      * Returns a {@code CertPathChecker} that the encapsulated
 322      * {@code CertPathBuilderSpi} implementation uses to check the revocation
 323      * status of certificates. A PKIX implementation returns objects of
 324      * type {@code PKIXRevocationChecker}. Each invocation of this method
 325      * returns a new instance of {@code CertPathChecker}.
 326      *
 327      * <p>The primary purpose of this method is to allow callers to specify
 328      * additional input parameters and options specific to revocation checking.
 329      * See the class description for an example.
 330      *
 331      * @return a {@code CertPathChecker}
 332      * @throws UnsupportedOperationException if the service provider does not
 333      *         support this method
 334      * @since 1.8
 335      */
 336     public final CertPathChecker getRevocationChecker() {
 337         return builderSpi.engineGetRevocationChecker();
 338     }
 339 }