1 files changed, 303 insertions, 0 deletions
diff --git a/libraries/spongycastle/prov/src/main/java/org/spongycastle/jce/provider/PKIXAttrCertPathBuilderSpi.java b/libraries/spongycastle/prov/src/main/java/org/spongycastle/jce/provider/PKIXAttrCertPathBuilderSpi.java
new file mode 100644
index 000000000..bf190f573
--- /dev/null
+++ b/libraries/spongycastle/prov/src/main/java/org/spongycastle/jce/provider/PKIXAttrCertPathBuilderSpi.java
@@ -0,0 +1,303 @@
+package org.spongycastle.jce.provider;
+
+import java.io.IOException;
+import java.security.InvalidAlgorithmParameterException;
+import java.security.Principal;
+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 java.util.Set;
+
+import javax.security.auth.x500.X500Principal;
+
+import org.spongycastle.jce.exception.ExtCertPathBuilderException;
+import org.spongycastle.util.Selector;
+import org.spongycastle.x509.ExtendedPKIXBuilderParameters;
+import org.spongycastle.x509.X509AttributeCertStoreSelector;
+import org.spongycastle.x509.X509AttributeCertificate;
+import org.spongycastle.x509.X509CertStoreSelector;
+
+public class PKIXAttrCertPathBuilderSpi
+    extends CertPathBuilderSpi
+{
+
+    /**
+     * 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;
+        if (params instanceof ExtendedPKIXBuilderParameters)
+        {
+            pkixParams = (ExtendedPKIXBuilderParameters) params;
+        }
+        else
+        {
+            pkixParams = (ExtendedPKIXBuilderParameters) ExtendedPKIXBuilderParameters
+                    .getInstance((PKIXBuilderParameters) params);
+        }
+
+        Collection targets;
+        Iterator targetIter;
+        List certPathList = new ArrayList();
+        X509AttributeCertificate cert;
+
+        // search target certificates
+
+        Selector certSelect = pkixParams.getTargetConstraints();
+        if (!(certSelect instanceof X509AttributeCertStoreSelector))
+        {
+            throw new CertPathBuilderException(
+                    "TargetConstraints must be an instance of "
+                            + X509AttributeCertStoreSelector.class.getName()
+                            + " for "+this.getClass().getName()+" class.");
+        }
+
+        try
+        {
+            targets = CertPathValidatorUtilities.findCertificates((X509AttributeCertStoreSelector)certSelect, pkixParams.getStores());
+        }
+        catch (AnnotatedException e)
+        {
+            throw new ExtCertPathBuilderException("Error finding target attribute certificate.", e);
+        }
+
+        if (targets.isEmpty())
+        {
+            throw new CertPathBuilderException(
+                    "No attribute certificate found matching targetContraints.");
+        }
+
+        CertPathBuilderResult result = null;
+
+        // check all potential target certificates
+        targetIter = targets.iterator();
+        while (targetIter.hasNext() && result == null)
+        {
+            cert = (X509AttributeCertificate) targetIter.next();
+            
+            X509CertStoreSelector selector = new X509CertStoreSelector();
+            Principal[] principals = cert.getIssuer().getPrincipals();
+            Set issuers = new HashSet();
+            for (int i = 0; i < principals.length; i++)
+            {
+                try
+                {
+                    if (principals[i] instanceof X500Principal)
+                    {
+                        selector.setSubject(((X500Principal)principals[i]).getEncoded());
+                    }
+                    issuers.addAll(CertPathValidatorUtilities.findCertificates(selector, pkixParams.getStores()));
+                    issuers.addAll(CertPathValidatorUtilities.findCertificates(selector, pkixParams.getCertStores()));
+                }
+                catch (AnnotatedException e)
+                {
+                    throw new ExtCertPathBuilderException(
+                        "Public key certificate for attribute certificate cannot be searched.",
+                        e);
+                }
+                catch (IOException e)
+                {
+                    throw new ExtCertPathBuilderException(
+                        "cannot encode X500Principal.",
+                        e);
+                }
+            }
+            if (issuers.isEmpty())
+            {
+                throw new CertPathBuilderException(
+                    "Public key certificate for attribute certificate cannot be found.");
+            }
+            Iterator it = issuers.iterator();
+            while (it.hasNext() && result == null)
+            {
+                result = build(cert, (X509Certificate)it.next(), pkixParams, certPathList);
+            }
+        }
+
+        if (result == null && certPathException != null)
+        {
+            throw new ExtCertPathBuilderException(
+                                    "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;
+
+    private CertPathBuilderResult build(X509AttributeCertificate attrCert, 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("RFC3281", 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)
+            {
+                CertPath certPath;
+                PKIXCertPathValidatorResult result;
+                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 additional 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();
+                    // TODO Use CertPathValidatorUtilities.isSelfIssued(issuer)?
+                    // if untrusted self signed certificate continue
+                    if (issuer.getIssuerX500Principal().equals(
+                            issuer.getSubjectX500Principal()))
+                    {
+                        continue;
+                    }
+                    builderResult = build(attrCert, issuer, pkixParams, tbvPath);
+                }
+            }
+        }
+        catch (AnnotatedException e)
+        {
+            certPathException = new AnnotatedException(
+                            "No valid certification path could be build.", e);
+        }
+        if (builderResult == null)
+        {
+            tbvPath.remove(tbvCert);
+        }
+        return builderResult;
+    }
+
+}