package org.bouncycastle.jce.cert;
import java.security.InvalidAlgorithmParameterException;
import java.security.NoSuchAlgorithmException;
import java.security.NoSuchProviderException;
import java.security.Provider;
import java.security.Security;
/**
* A class for validating certification paths (also known as certificate
* chains).<br />
* <br />
* This class uses a provider-based architecture, as described in the Java
* Cryptography Architecture. To create a <code>CertPathValidator</code>,
* call one of the static <code>getInstance</code> methods, passing in the
* algorithm name of the <code>CertPathValidator</code> desired and
* optionally the name of the provider desired. <br />
* <br />
* Once a <code>CertPathValidator</code> 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</code> to be validated
* and an algorithm-specific set of parameters. If successful, the result is
* returned in an object that implements the
* <code>CertPathValidatorResult</code> interface.<br />
* <br />
* <b>Concurrent Access</b><br />
* <br />
* 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.<br />
* <br />
* 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</code> instance concurrently should
* synchronize amongst themselves and provide the necessary locking. Multiple
* threads each manipulating a different <code>CertPathValidator</code>
* instance need not synchronize.<br />
* <br />
* @see CertPath
**/
public class CertPathValidator extends Object
{
private CertPathValidatorSpi validatorSpi;
private Provider provider;
private String algorithm;
/**
* Creates a <code>CertPathValidator</code> 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</code> object that implements the
* specified algorithm.<br />
* <br />
* If the default provider package provides an implementation of the
* specified <code>CertPathValidator</code> algorithm, an instance of
* <code>CertPathValidator</code> containing that implementation is
* returned. If the requested algorithm is not available in the default
* package, other packages are searched.
*
* @param algorithm
* the name of the requested <code>CertPathValidator</code>
* algorithm
*
* @return a <code>CertPathValidator</code> object that implements the
* specified algorithm
*
* @exception NoSuchAlgorithmException
* if the requested algorithm is not available in the default
* provider package or any of the other provider packages
* that were searched
*/
public static CertPathValidator getInstance(String algorithm)
throws NoSuchAlgorithmException
{
try
{
CertUtil.Implementation imp = CertUtil.getImplementation(
"CertPathValidator", algorithm, (String)null);
if (imp != null)
{
return new CertPathValidator((CertPathValidatorSpi)imp
.getEngine(), imp.getProvider(), algorithm);
}
}
catch (NoSuchProviderException ex)
{
}
throw new NoSuchAlgorithmException("can't find algorithm " + algorithm);
}
/**
* Returns a <code>CertPathValidator</code> object that implements the
* specified algorithm, as supplied by the specified provider.
*
* @param algorithm
* the name of the requested <code>CertPathValidator</code>
* algorithm
* @param provider
* the name of the provider
*
* @return a <code>CertPathValidator</code> object that implements the
* specified algorithm, as supplied by the specified provider
*
* @exception NoSuchAlgorithmException
* if the requested algorithm is not available from the
* specified provider
* @exception NoSuchProviderException
* if the provider has not been configured
* @exception IllegalArgumentException
* if the <code>provider</code> is null
*/
public static CertPathValidator getInstance(String algorithm,
String provider) throws NoSuchAlgorithmException,
NoSuchProviderException
{
if (provider == null)
{
throw new IllegalArgumentException("provider must be non-null");
}
CertUtil.Implementation imp = CertUtil.getImplementation(
"CertPathValidator", algorithm, provider);
if (imp != null)
{
return new CertPathValidator((CertPathValidatorSpi)imp.getEngine(),
imp.getProvider(), algorithm);
}
throw new NoSuchAlgorithmException("can't find algorithm " + algorithm);
}
/**
* Returns a <code>CertPathValidator</code> object that implements the
* specified algorithm, as supplied by the specified provider. Note: the
* <code>provider</code> doesn't have to be registered.
*
* @param algorithm
* the name of the requested <code>CertPathValidator</code>
* algorithm
* @param provider
* the provider
*
* @return a <code>CertPathValidator</code> object that implements the
* specified algorithm, as supplied by the specified provider
*
* @exception NoSuchAlgorithmException
* if the requested algorithm is not available from the
* specified provider
* @exception IllegalArgumentException
* if the <code>provider</code> is null
*/
public static CertPathValidator getInstance(String algorithm,
Provider provider) throws NoSuchAlgorithmException
{
if (provider == null)
{
throw new IllegalArgumentException("provider must be non-null");
}
CertUtil.Implementation imp = CertUtil.getImplementation(
"CertPathValidator", algorithm, provider);
if (imp != null)
{
return new CertPathValidator((CertPathValidatorSpi)imp.getEngine(),
provider, algorithm);
}
throw new NoSuchAlgorithmException("can't find algorithm " + algorithm);
}
/**
* Returns the <code>Provider</code> of this
* <code>CertPathValidator</code>.
*
* @return the <code>Provider</code> of this
* <code>CertPathValidator</code>
*/
public final Provider getProvider()
{
return provider;
}
/**
* Returns the algorithm name of this <code>CertPathValidator</code>.
*
* @return the algorithm name of this <code>CertPathValidator</code>
*/
public final String getAlgorithm()
{
return algorithm;
}
/**
* Validates the specified certification path using the specified algorithm
* parameter set.<br />
* <br />
* The <code>CertPath</code> specified must be of a type that is supported
* by the validation algorithm, otherwise an
* <code>InvalidAlgorithmParameterException</code> will be thrown. For
* example, a <code>CertPathValidator</code> that implements the PKIX
* algorithm validates <code>CertPath</code> objects of type X.509.
*
* @param certPath
* the <code>CertPath</code> to be validated
* @param params
* the algorithm parameters
*
* @return the result of the validation algorithm
*
* @exception CertPathValidatorException
* if the <code>CertPath</code> does not validate
* @exception InvalidAlgorithmParameterException
* if the specified parameters or the type of the specified
* <code>CertPath</code> are inappropriate for this
* <code>CertPathValidator</code>
*/
public final CertPathValidatorResult validate(CertPath certPath,
CertPathParameters params) throws CertPathValidatorException,
InvalidAlgorithmParameterException
{
return validatorSpi.engineValidate(certPath, params);
}
/**
* Returns the default <code>CertPathValidator</code> type as specified in
* the Java security properties file, or the string "PKIX" if no
* such property exists. The Java security properties file is located in the
* file named <JAVA_HOME>/lib/security/java.security, where
* <JAVA_HOME> refers to the directory where the SDK was installed.<br />
* <br />
* The default <code>CertPathValidator</code> type can be used by
* applications that do not want to use a hard-coded type when calling one
* of the <code>getInstance</code> methods, and want to provide a default
* type in case a user does not specify its own.<br />
* <br />
* The default <code>CertPathValidator</code> type can be changed by
* setting the value of the "certpathvalidator.type" security property (in
* the Java security properties file) to the desired type.
*
* @return the default <code>CertPathValidator</code> type as specified in
* the Java security properties file, or the string "PKIX"
* if no such property exists.
*/
public static final String getDefaultType()
{
String defaulttype = null;
defaulttype = Security.getProperty("certpathvalidator.type");
if (defaulttype == null || defaulttype.length() <= 0)
{
return "PKIX";
}
else
{
return defaulttype;
}
}
}