package org.bouncycastle.jce.provider;

import java.security.InvalidAlgorithmParameterException;
import java.security.cert.CertPath;
import java.security.cert.CertPathBuilderException;
import java.security.cert.CertPathBuilderResult;
import java.security.cert.CertPathBuilderSpi;
import java.security.cert.CertPathParameters;
import java.security.cert.CertPathValidator;
import java.security.cert.CertificateFactory;
import java.security.cert.CertificateParsingException;
import java.security.cert.PKIXBuilderParameters;
import java.security.cert.PKIXCertPathBuilderResult;
import java.security.cert.PKIXCertPathValidatorResult;
import java.security.cert.X509Certificate;
import java.util.ArrayList;
import java.util.Collection;
import java.util.HashSet;
import java.util.Iterator;
import java.util.List;

import org.bouncycastle.jce.exception.ExtCertPathBuilderException;
import org.bouncycastle.util.Selector;
import org.bouncycastle.x509.ExtendedPKIXBuilderParameters;
import org.bouncycastle.x509.X509CertStoreSelector;

Implements the PKIX CertPathBuilding algorithm for BouncyCastle.
See Also:
  • CertPathBuilderSpi
/** * Implements the PKIX CertPathBuilding algorithm for BouncyCastle. * * @see CertPathBuilderSpi */
public class PKIXCertPathBuilderSpi extends CertPathBuilderSpi {
Build and validate a CertPath using the given parameter.
Params:
  • params – PKIXBuilderParameters object containing all information to build the CertPath
/** * Build and validate a CertPath using the given parameter. * * @param params PKIXBuilderParameters object containing all information to * build the CertPath */
public CertPathBuilderResult engineBuild(CertPathParameters params) throws CertPathBuilderException, InvalidAlgorithmParameterException { if (!(params instanceof PKIXBuilderParameters) && !(params instanceof ExtendedPKIXBuilderParameters)) { throw new InvalidAlgorithmParameterException( "Parameters must be an instance of " + PKIXBuilderParameters.class.getName() + " or " + ExtendedPKIXBuilderParameters.class.getName() + "."); } ExtendedPKIXBuilderParameters pkixParams = null; if (params instanceof ExtendedPKIXBuilderParameters) { pkixParams = (ExtendedPKIXBuilderParameters) params; } else { pkixParams = (ExtendedPKIXBuilderParameters) ExtendedPKIXBuilderParameters .getInstance((PKIXBuilderParameters) params); } Collection targets; Iterator targetIter; List certPathList = new ArrayList(); X509Certificate cert; // search target certificates Selector certSelect = pkixParams.getTargetConstraints(); if (!(certSelect instanceof X509CertStoreSelector)) { throw new CertPathBuilderException( "TargetConstraints must be an instance of " + X509CertStoreSelector.class.getName() + " for " + this.getClass().getName() + " class."); } try { targets = CertPathValidatorUtilities.findCertificates((X509CertStoreSelector)certSelect, pkixParams.getStores()); targets.addAll(CertPathValidatorUtilities.findCertificates((X509CertStoreSelector)certSelect, pkixParams.getCertStores())); } catch (AnnotatedException e) { throw new ExtCertPathBuilderException( "Error finding target certificate.", e); } if (targets.isEmpty()) { throw new CertPathBuilderException( "No certificate found matching targetContraints."); } CertPathBuilderResult result = null; // check all potential target certificates targetIter = targets.iterator(); while (targetIter.hasNext() && result == null) { cert = (X509Certificate) targetIter.next(); result = build(cert, pkixParams, certPathList); } if (result == null && certPathException != null) { if (certPathException instanceof AnnotatedException) { throw new CertPathBuilderException(certPathException.getMessage(), certPathException.getCause()); } throw new CertPathBuilderException( "Possible certificate chain could not be validated.", certPathException); } if (result == null && certPathException == null) { throw new CertPathBuilderException( "Unable to find certificate chain."); } return result; } private Exception certPathException; protected CertPathBuilderResult build(X509Certificate tbvCert, ExtendedPKIXBuilderParameters pkixParams, List tbvPath) { // If tbvCert is readily present in tbvPath, it indicates having run // into a cycle in the // PKI graph. if (tbvPath.contains(tbvCert)) { return null; } // step out, the certificate is not allowed to appear in a certification // chain. if (pkixParams.getExcludedCerts().contains(tbvCert)) { return null; } // test if certificate path exceeds maximum length if (pkixParams.getMaxPathLength() != -1) { if (tbvPath.size() - 1 > pkixParams.getMaxPathLength()) { return null; } } tbvPath.add(tbvCert); CertificateFactory cFact; CertPathValidator validator; CertPathBuilderResult builderResult = null; try { cFact = CertificateFactory.getInstance("X.509", BouncyCastleProvider.PROVIDER_NAME); validator = CertPathValidator.getInstance("PKIX", BouncyCastleProvider.PROVIDER_NAME); } catch (Exception e) { // cannot happen throw new RuntimeException("Exception creating support classes."); } try { // check whether the issuer of <tbvCert> is a TrustAnchor if (CertPathValidatorUtilities.findTrustAnchor(tbvCert, pkixParams.getTrustAnchors(), pkixParams.getSigProvider()) != null) { // exception message from possibly later tried certification // chains CertPath certPath = null; PKIXCertPathValidatorResult result = null; try { certPath = cFact.generateCertPath(tbvPath); } catch (Exception e) { throw new AnnotatedException( "Certification path could not be constructed from certificate list.", e); } try { result = (PKIXCertPathValidatorResult) validator.validate( certPath, pkixParams); } catch (Exception e) { throw new AnnotatedException( "Certification path could not be validated.", e); } return new PKIXCertPathBuilderResult(certPath, result .getTrustAnchor(), result.getPolicyTree(), result .getPublicKey()); } else { // add additional X.509 stores from locations in certificate try { CertPathValidatorUtilities.addAdditionalStoresFromAltNames( tbvCert, pkixParams); } catch (CertificateParsingException e) { throw new AnnotatedException( "No additiontal X.509 stores can be added from certificate locations.", e); } Collection issuers = new HashSet(); // try to get the issuer certificate from one // of the stores try { issuers.addAll(CertPathValidatorUtilities.findIssuerCerts(tbvCert, pkixParams)); } catch (AnnotatedException e) { throw new AnnotatedException( "Cannot find issuer certificate for certificate in certification path.", e); } if (issuers.isEmpty()) { throw new AnnotatedException( "No issuer certificate for certificate in certification path found."); } Iterator it = issuers.iterator(); while (it.hasNext() && builderResult == null) { X509Certificate issuer = (X509Certificate) it.next(); builderResult = build(issuer, pkixParams, tbvPath); } } } catch (AnnotatedException e) { certPathException = e; } if (builderResult == null) { tbvPath.remove(tbvCert); } return builderResult; } }