1 files changed, 261 insertions, 0 deletions
diff --git a/libraries/spongycastle/prov/src/main/java/org/spongycastle/jce/provider/PKIXCertPathBuilderSpi.java b/libraries/spongycastle/prov/src/main/java/org/spongycastle/jce/provider/PKIXCertPathBuilderSpi.java
new file mode 100644
index 000000000..e060b4f02
--- /dev/null
+++ b/libraries/spongycastle/prov/src/main/java/org/spongycastle/jce/provider/PKIXCertPathBuilderSpi.java
@@ -0,0 +1,261 @@
+package org.spongycastle.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.spongycastle.jce.exception.ExtCertPathBuilderException;
+import org.spongycastle.util.Selector;
+import org.spongycastle.x509.ExtendedPKIXBuilderParameters;
+import org.spongycastle.x509.X509CertStoreSelector;
+
+/**
+ * Implements the PKIX CertPathBuilding algorithm for BouncyCastle.
+ * 
+ * @see CertPathBuilderSpi
+ */
+public class PKIXCertPathBuilderSpi
+    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 = 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;
+    }
+
+}