Java tutorial
/* * Copyright (c) 2000, 2017, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ package java.security.cert; import java.security.AccessController; import java.security.InvalidAlgorithmParameterException; import java.security.NoSuchAlgorithmException; import java.security.NoSuchProviderException; import java.security.PrivilegedAction; import java.security.Provider; import java.security.Security; import java.util.Objects; import sun.security.jca.*; import sun.security.jca.GetInstance.Instance; /** * A class for validating certification paths (also known as certificate * chains). * <p> * This class uses a provider-based architecture. * To create a {@code CertPathValidator}, * call one of the static {@code getInstance} methods, passing in the * algorithm name of the {@code CertPathValidator} desired and * optionally the name of the provider desired. * * <p>Once a {@code CertPathValidator} object has been created, it can * be used to validate certification paths by calling the {@link #validate * validate} method and passing it the {@code CertPath} to be validated * and an algorithm-specific set of parameters. If successful, the result is * returned in an object that implements the * {@code CertPathValidatorResult} interface. * * <p>The {@link #getRevocationChecker} method allows an application to specify * additional algorithm-specific parameters and options used by the * {@code CertPathValidator} when checking the revocation status of * certificates. Here is an example demonstrating how it is used with the PKIX * algorithm: * * <pre> * CertPathValidator cpv = CertPathValidator.getInstance("PKIX"); * PKIXRevocationChecker rc = (PKIXRevocationChecker)cpv.getRevocationChecker(); * rc.setOptions(EnumSet.of(Option.SOFT_FAIL)); * params.addCertPathChecker(rc); * CertPathValidatorResult cpvr = cpv.validate(path, params); * </pre> * * <p>Every implementation of the Java platform is required to support the * following standard {@code CertPathValidator} algorithm: * <ul> * <li>{@code PKIX}</li> * </ul> * This algorithm is described in the <a href= * "{@docRoot}/../specs/security/standard-names.html#certpathvalidator-algorithms"> * CertPathValidator section</a> of the * Java Security Standard Algorithm Names Specification. * Consult the release documentation for your implementation to see if any * other algorithms are supported. * * <p> * <b>Concurrent Access</b> * <p> * The static methods of this class are guaranteed to be thread-safe. * Multiple threads may concurrently invoke the static methods defined in * this class with no ill effects. * <p> * However, this is not true for the non-static methods defined by this class. * Unless otherwise documented by a specific provider, threads that need to * access a single {@code CertPathValidator} instance concurrently should * synchronize amongst themselves and provide the necessary locking. Multiple * threads each manipulating a different {@code CertPathValidator} * instance need not synchronize. * * @see CertPath * * @since 1.4 * @author Yassir Elley */ public class CertPathValidator { /* * Constant to lookup in the Security properties file to determine * the default certpathvalidator type. In the Security properties file, * the default certpathvalidator type is given as: * <pre> * certpathvalidator.type=PKIX * </pre> */ private static final String CPV_TYPE = "certpathvalidator.type"; private final CertPathValidatorSpi validatorSpi; private final Provider provider; private final String algorithm; /** * Creates a {@code CertPathValidator} object of the given algorithm, * and encapsulates the given provider implementation (SPI object) in it. * * @param validatorSpi the provider implementation * @param provider the provider * @param algorithm the algorithm name */ protected CertPathValidator(CertPathValidatorSpi validatorSpi, Provider provider, String algorithm) { this.validatorSpi = validatorSpi; this.provider = provider; this.algorithm = algorithm; } /** * Returns a {@code CertPathValidator} object that implements the * specified algorithm. * * <p> This method traverses the list of registered security Providers, * starting with the most preferred Provider. * A new CertPathValidator object encapsulating the * CertPathValidatorSpi implementation from the first * Provider that supports the specified algorithm is returned. * * <p> Note that the list of registered providers may be retrieved via * the {@link Security#getProviders() Security.getProviders()} method. * * @implNote * The JDK Reference Implementation additionally uses the * {@code jdk.security.provider.preferred} * {@link Security#getProperty(String) Security} property to determine * the preferred provider order for the specified algorithm. This * may be different than the order of providers returned by * {@link Security#getProviders() Security.getProviders()}. * * @param algorithm the name of the requested {@code CertPathValidator} * algorithm. See the CertPathValidator section in the <a href= * "{@docRoot}/../specs/security/standard-names.html#certpathvalidator-algorithms"> * Java Security Standard Algorithm Names Specification</a> * for information about standard algorithm names. * * @return a {@code CertPathValidator} object that implements the * specified algorithm * * @throws NoSuchAlgorithmException if no {@code Provider} supports a * {@code CertPathValidatorSpi} implementation for the * specified algorithm * * @throws NullPointerException if {@code algorithm} is {@code null} * * @see java.security.Provider */ public static CertPathValidator getInstance(String algorithm) throws NoSuchAlgorithmException { Objects.requireNonNull(algorithm, "null algorithm name"); Instance instance = GetInstance.getInstance("CertPathValidator", CertPathValidatorSpi.class, algorithm); return new CertPathValidator((CertPathValidatorSpi) instance.impl, instance.provider, algorithm); } /** * Returns a {@code CertPathValidator} object that implements the * specified algorithm. * * <p> A new CertPathValidator object encapsulating the * CertPathValidatorSpi implementation from the specified provider * is returned. The specified provider must be registered * in the security provider list. * * <p> Note that the list of registered providers may be retrieved via * the {@link Security#getProviders() Security.getProviders()} method. * * @param algorithm the name of the requested {@code CertPathValidator} * algorithm. See the CertPathValidator section in the <a href= * "{@docRoot}/../specs/security/standard-names.html#certpathvalidator-algorithms"> * Java Security Standard Algorithm Names Specification</a> * for information about standard algorithm names. * * @param provider the name of the provider. * * @return a {@code CertPathValidator} object that implements the * specified algorithm * * @throws IllegalArgumentException if the {@code provider} is * {@code null} or empty * * @throws NoSuchAlgorithmException if a {@code CertPathValidatorSpi} * implementation for the specified algorithm is not * available from the specified provider * * @throws NoSuchProviderException if the specified provider is not * registered in the security provider list * * @throws NullPointerException if {@code algorithm} is {@code null} * * @see java.security.Provider */ public static CertPathValidator getInstance(String algorithm, String provider) throws NoSuchAlgorithmException, NoSuchProviderException { Objects.requireNonNull(algorithm, "null algorithm name"); Instance instance = GetInstance.getInstance("CertPathValidator", CertPathValidatorSpi.class, algorithm, provider); return new CertPathValidator((CertPathValidatorSpi) instance.impl, instance.provider, algorithm); } /** * Returns a {@code CertPathValidator} object that implements the * specified algorithm. * * <p> A new CertPathValidator object encapsulating the * CertPathValidatorSpi implementation from the specified Provider * object is returned. Note that the specified Provider object * does not have to be registered in the provider list. * * @param algorithm the name of the requested {@code CertPathValidator} * algorithm. See the CertPathValidator section in the <a href= * "{@docRoot}/../specs/security/standard-names.html#certpathvalidator-algorithms"> * Java Security Standard Algorithm Names Specification</a> * for information about standard algorithm names. * * @param provider the provider. * * @return a {@code CertPathValidator} object that implements the * specified algorithm * * @throws IllegalArgumentException if the {@code provider} is * {@code null} * * @throws NoSuchAlgorithmException if a {@code CertPathValidatorSpi} * implementation for the specified algorithm is not available * from the specified Provider object * * @throws NullPointerException if {@code algorithm} is {@code null} * * @see java.security.Provider */ public static CertPathValidator getInstance(String algorithm, Provider provider) throws NoSuchAlgorithmException { Objects.requireNonNull(algorithm, "null algorithm name"); Instance instance = GetInstance.getInstance("CertPathValidator", CertPathValidatorSpi.class, algorithm, provider); return new CertPathValidator((CertPathValidatorSpi) instance.impl, instance.provider, algorithm); } /** * Returns the {@code Provider} of this * {@code CertPathValidator}. * * @return the {@code Provider} of this {@code CertPathValidator} */ public final Provider getProvider() { return this.provider; } /** * Returns the algorithm name of this {@code CertPathValidator}. * * @return the algorithm name of this {@code CertPathValidator} */ public final String getAlgorithm() { return this.algorithm; } /** * Validates the specified certification path using the specified * algorithm parameter set. * <p> * The {@code CertPath} specified must be of a type that is * supported by the validation algorithm, otherwise an * {@code InvalidAlgorithmParameterException} will be thrown. For * example, a {@code CertPathValidator} that implements the PKIX * algorithm validates {@code CertPath} objects of type X.509. * * @param certPath the {@code CertPath} to be validated * @param params the algorithm parameters * @return the result of the validation algorithm * @exception CertPathValidatorException if the {@code CertPath} * does not validate * @exception InvalidAlgorithmParameterException if the specified * parameters or the type of the specified {@code CertPath} are * inappropriate for this {@code CertPathValidator} */ public final CertPathValidatorResult validate(CertPath certPath, CertPathParameters params) throws CertPathValidatorException, InvalidAlgorithmParameterException { return validatorSpi.engineValidate(certPath, params); } /** * Returns the default {@code CertPathValidator} type as specified by * the {@code certpathvalidator.type} security property, or the string * {@literal "PKIX"} if no such property exists. * * <p>The default {@code CertPathValidator} type can be used by * applications that do not want to use a hard-coded type when calling one * of the {@code getInstance} methods, and want to provide a default * type in case a user does not specify its own. * * <p>The default {@code CertPathValidator} type can be changed by * setting the value of the {@code certpathvalidator.type} security * property to the desired type. * * @see java.security.Security security properties * @return the default {@code CertPathValidator} type as specified * by the {@code certpathvalidator.type} security property, or the string * {@literal "PKIX"} if no such property exists. */ public static final String getDefaultType() { String cpvtype = AccessController.doPrivileged(new PrivilegedAction<>() { public String run() { return Security.getProperty(CPV_TYPE); } }); return (cpvtype == null) ? "PKIX" : cpvtype; } /** * Returns a {@code CertPathChecker} that the encapsulated * {@code CertPathValidatorSpi} implementation uses to check the revocation * status of certificates. A PKIX implementation returns objects of * type {@code PKIXRevocationChecker}. Each invocation of this method * returns a new instance of {@code CertPathChecker}. * * <p>The primary purpose of this method is to allow callers to specify * additional input parameters and options specific to revocation checking. * See the class description for an example. * * @return a {@code CertPathChecker} * @throws UnsupportedOperationException if the service provider does not * support this method * @since 1.8 */ public final CertPathChecker getRevocationChecker() { return validatorSpi.engineGetRevocationChecker(); } }