Java DistributionPointName.getType方法代码示例

import org.bouncycastle.asn1.x509.DistributionPointName; //导入方法依赖的package包/类
protected Vector getCRLDistUrls(CRLDistPoint crlDistPoints)
{
    Vector urls = new Vector();
    
    if (crlDistPoints != null)
    {
        DistributionPoint[] distPoints = crlDistPoints.getDistributionPoints();
        for (int i = 0; i < distPoints.length; i++)
        {
            DistributionPointName dp_name = distPoints[i].getDistributionPoint();
            if (dp_name.getType() == DistributionPointName.FULL_NAME)
            {
                GeneralName[] generalNames = GeneralNames.getInstance(dp_name.getName()).getNames();
                for (int j = 0; j < generalNames.length; j++)
                {
                    if (generalNames[j].getTagNo() == GeneralName.uniformResourceIdentifier)
                    {
                        String url = ((DERIA5String) generalNames[j].getName()).getString();
                        urls.add(url);
                    }
                }
            }
        }
    }
    return urls;
}
 

import org.bouncycastle.asn1.x509.DistributionPointName; //导入方法依赖的package包/类
/**
 * 
 * @return A list of ulrs that inform the location of the certificate revocation lists
 * @throws IOException exception
 */
public List<String> getCRLDistributionPoint() throws IOException {

    List<String> crlUrls = new ArrayList<>();
    ASN1Primitive primitive = getExtensionValue(Extension.cRLDistributionPoints.getId());
    if (primitive == null) {
        return null;
    }
    CRLDistPoint crlDistPoint = CRLDistPoint.getInstance(primitive);
    DistributionPoint[] distributionPoints = crlDistPoint.getDistributionPoints();

    for (DistributionPoint distributionPoint : distributionPoints) {
        DistributionPointName dpn = distributionPoint.getDistributionPoint();
        // Look for URIs in fullName
        if (dpn != null) {
            if (dpn.getType() == DistributionPointName.FULL_NAME) {
                GeneralName[] genNames = GeneralNames.getInstance(dpn.getName()).getNames();
                for (GeneralName genName : genNames) {
                    if (genName.getTagNo() == GeneralName.uniformResourceIdentifier) {
                        String url = DERIA5String.getInstance(genName.getName()).getString();
                        crlUrls.add(url);
                        logger.info("Adicionando a url {}", url);
                    }
                }
            }
        }
    }
    return crlUrls;
}
 

import org.bouncycastle.asn1.x509.DistributionPointName; //导入方法依赖的package包/类
public static List<String> getCrlDistributionPoints(byte[] crldpExt)
		throws CertificateParsingException, IOException {
	if (crldpExt == null) {
		return new ArrayList<String>();
	}
	ASN1InputStream oAsnInStream = new ASN1InputStream(
			new ByteArrayInputStream(crldpExt));
	DERObject derObjCrlDP = oAsnInStream.readObject();
	DEROctetString dosCrlDP = (DEROctetString) derObjCrlDP;
	byte[] crldpExtOctets = dosCrlDP.getOctets();
	ASN1InputStream oAsnInStream2 = new ASN1InputStream(
			new ByteArrayInputStream(crldpExtOctets));
	DERObject derObj2 = oAsnInStream2.readObject();
	CRLDistPoint distPoint = CRLDistPoint.getInstance(derObj2);
	List<String> crlUrls = new ArrayList<String>();
	for (DistributionPoint dp : distPoint.getDistributionPoints()) {
		DistributionPointName dpn = dp.getDistributionPoint();
		// Look for URIs in fullName
		if (dpn != null && dpn.getType() == DistributionPointName.FULL_NAME) {
			GeneralName[] genNames = GeneralNames
					.getInstance(dpn.getName()).getNames();
			// Look for an URI
			for (int j = 0; j < genNames.length; j++) {
				if (genNames[j].getTagNo() == GeneralName.uniformResourceIdentifier) {
					String url = DERIA5String.getInstance(
							genNames[j].getName()).getString();
					crlUrls.add(url);
				}
			}
		}
	}
	return crlUrls;
}
 

import org.bouncycastle.asn1.x509.DistributionPointName; //导入方法依赖的package包/类
public static List<String> getCrlDistributionPoints(byte[] crldpExt)
		throws CertificateParsingException, IOException {
	if (crldpExt == null) {
		return new ArrayList<String>();
	}
	ASN1InputStream oAsnInStream = new ASN1InputStream(
			new ByteArrayInputStream(crldpExt));
	ASN1Primitive derObjCrlDP = oAsnInStream.readObject();
	DEROctetString dosCrlDP = (DEROctetString) derObjCrlDP;
	byte[] crldpExtOctets = dosCrlDP.getOctets();
	ASN1InputStream oAsnInStream2 = new ASN1InputStream(
			new ByteArrayInputStream(crldpExtOctets));
	ASN1Primitive derObj2 = oAsnInStream2.readObject();
	CRLDistPoint distPoint = CRLDistPoint.getInstance(derObj2);
	List<String> crlUrls = new ArrayList<String>();
	for (DistributionPoint dp : distPoint.getDistributionPoints()) {
		DistributionPointName dpn = dp.getDistributionPoint();
		// Look for URIs in fullName
		if (dpn != null && dpn.getType() == DistributionPointName.FULL_NAME) {
			GeneralName[] genNames = GeneralNames
					.getInstance(dpn.getName()).getNames();
			// Look for an URI
			for (int j = 0; j < genNames.length; j++) {
				if (genNames[j].getTagNo() == GeneralName.uniformResourceIdentifier) {
					String url = DERIA5String.getInstance(
							genNames[j].getName()).getString();
					crlUrls.add(url);
				}
			}
		}
	}
	return crlUrls;
}
 

import org.bouncycastle.asn1.x509.DistributionPointName; //导入方法依赖的package包/类
protected void checkCriticalExtensions(CRLValidity validity, Collection<String> criticalExtensionsOid, byte[] issuingDistributionPointBinary) {
	if (criticalExtensionsOid == null || criticalExtensionsOid.isEmpty()) {
		validity.setUnknownCriticalExtension(false);
	} else {
		IssuingDistributionPoint issuingDistributionPoint = IssuingDistributionPoint
				.getInstance(ASN1OctetString.getInstance(issuingDistributionPointBinary).getOctets());
		final boolean onlyAttributeCerts = issuingDistributionPoint.onlyContainsAttributeCerts();
		final boolean onlyCaCerts = issuingDistributionPoint.onlyContainsCACerts();
		final boolean onlyUserCerts = issuingDistributionPoint.onlyContainsUserCerts();
		final boolean indirectCrl = issuingDistributionPoint.isIndirectCRL();
		ReasonFlags onlySomeReasons = issuingDistributionPoint.getOnlySomeReasons();
		DistributionPointName distributionPoint = issuingDistributionPoint.getDistributionPoint();
		boolean urlFound = false;
		if (DistributionPointName.FULL_NAME == distributionPoint.getType()) {
			final GeneralNames generalNames = (GeneralNames) distributionPoint.getName();
			if ((generalNames != null) && (generalNames.getNames() != null && generalNames.getNames().length > 0)) {
				for (GeneralName generalName : generalNames.getNames()) {
					if (GeneralName.uniformResourceIdentifier == generalName.getTagNo()) {
						ASN1String str = (ASN1String) ((DERTaggedObject) generalName.toASN1Primitive()).getObject();
						validity.setUrl(str.getString());
						urlFound = true;
					}
				}
			}
		}

		if (!(onlyAttributeCerts && onlyCaCerts && onlyUserCerts && indirectCrl) && (onlySomeReasons == null) && urlFound) {
			validity.setUnknownCriticalExtension(false);
		}
	}
}
 

import org.bouncycastle.asn1.x509.DistributionPointName; //导入方法依赖的package包/类
/**
 * Gives back the {@code List} of CRL URI meta-data found within the given X509 certificate.
 *
 * @param certificateToken
 *            the cert token certificate
 * @param checkInTrustAnchors
 *            if true, the method will search in the ServiceSupplyPoint urls
 * @return the {@code List} of CRL URI, or empty list if the extension is not present
 */
public static List<String> getCrlUrls(final CertificateToken certificateToken, boolean checkInTrustAnchors) {
	final List<String> urls = new ArrayList<String>();

	final byte[] crlDistributionPointsBytes = certificateToken.getCertificate().getExtensionValue(Extension.cRLDistributionPoints.getId());
	if (crlDistributionPointsBytes != null) {
		try {
			final ASN1Sequence asn1Sequence = DSSASN1Utils.getAsn1SequenceFromDerOctetString(crlDistributionPointsBytes);
			final CRLDistPoint distPoint = CRLDistPoint.getInstance(asn1Sequence);
			final DistributionPoint[] distributionPoints = distPoint.getDistributionPoints();
			for (final DistributionPoint distributionPoint : distributionPoints) {

				final DistributionPointName distributionPointName = distributionPoint.getDistributionPoint();
				if (DistributionPointName.FULL_NAME != distributionPointName.getType()) {
					continue;
				}
				final GeneralNames generalNames = (GeneralNames) distributionPointName.getName();
				final GeneralName[] names = generalNames.getNames();
				for (final GeneralName name : names) {
					String location = parseGn(name);
					if (location != null) {
						urls.add(location);
					}
				}
			}
		} catch (Exception e) {
			LOG.error("Unable to parse cRLDistributionPoints", e);
		}
	}

	if (Utils.isCollectionEmpty(urls) && checkInTrustAnchors) {
		return getServiceSupplyPoints(certificateToken, "crl", "certificateRevocationList");
	}
	return urls;
}
 

import org.bouncycastle.asn1.x509.DistributionPointName; //导入方法依赖的package包/类
public String getCrlUri(X509Certificate certificate) throws IOException {
	ASN1Primitive obj;
	try {
		obj = getExtensionValue(certificate, Extension.cRLDistributionPoints.getId());
	} catch (IOException ex) {
		log.error("Failed to get CRL URL", ex);
		return null;
	}

	if (obj == null) {
		return null;
	}

	CRLDistPoint distPoint = CRLDistPoint.getInstance(obj);

	DistributionPoint[] distributionPoints = distPoint.getDistributionPoints();
	for (DistributionPoint distributionPoint : distributionPoints) {
		DistributionPointName distributionPointName = distributionPoint.getDistributionPoint();
		if (DistributionPointName.FULL_NAME != distributionPointName.getType()) {
			continue;
		}

		GeneralNames generalNames = (GeneralNames) distributionPointName.getName();
		GeneralName[] names = generalNames.getNames();
		for (GeneralName name : names) {
			if (name.getTagNo() != GeneralName.uniformResourceIdentifier) {
				continue;
			}

			DERIA5String derStr = DERIA5String.getInstance((ASN1TaggedObject) name.toASN1Primitive(), false);
			return derStr.getString();
		}
	}

	return null;
}
 

import org.bouncycastle.asn1.x509.DistributionPointName; //导入方法依赖的package包/类
/**
 * Extracts all CRL distribution point URLs from the "CRL Distribution Point"
 * extension in a X.509 certificate. If CRL distribution point extension is
 * unavailable, returns an empty list. 
 */
public static List<String> getCrlDistributionPoints(
		X509Certificate cert) throws CertificateParsingException, IOException {
	byte[] crldpExt = cert.getExtensionValue(
			X509Extensions.CRLDistributionPoints.getId());
	ASN1InputStream oAsnInStream = new ASN1InputStream(
			new ByteArrayInputStream(crldpExt));
	
	ASN1Primitive derObjCrlDP = oAsnInStream.readObject();
	DEROctetString dosCrlDP = (DEROctetString) derObjCrlDP;
	byte[] crldpExtOctets = dosCrlDP.getOctets();
	
	ASN1InputStream oAsnInStream2 = new ASN1InputStream(
			new ByteArrayInputStream(crldpExtOctets));
	
	ASN1Primitive derObj2 = oAsnInStream2.readObject();
	CRLDistPoint distPoint = CRLDistPoint.getInstance(derObj2);
	List<String> crlUrls = new ArrayList<String>();
	for (DistributionPoint dp : distPoint.getDistributionPoints()) {
		System.out.println(dp);
           DistributionPointName dpn = dp.getDistributionPoint();
           // Look for URIs in fullName
           if (dpn != null) {
               if (dpn.getType() == DistributionPointName.FULL_NAME) {
                   GeneralName[] genNames = GeneralNames.getInstance(
                       dpn.getName()).getNames();
                   // Look for an URI
                   for (int j = 0; j < genNames.length; j++) {
                       if (genNames[j].getTagNo() == GeneralName.uniformResourceIdentifier) {
                           String url = DERIA5String.getInstance(
                               genNames[j].getName()).getString();
                           crlUrls.add(url);
                       }
                   }
               }
           }
	}
	return crlUrls;
}
 

import org.bouncycastle.asn1.x509.DistributionPointName; //导入方法依赖的package包/类
protected static void addAdditionalStoresFromCRLDistributionPoint(
    CRLDistPoint crldp, ExtendedPKIXParameters pkixParams)
    throws AnnotatedException
{
    if (crldp != null)
    {
        DistributionPoint dps[] = null;
        try
        {
            dps = crldp.getDistributionPoints();
        }
        catch (Exception e)
        {
            throw new AnnotatedException(
                "Distribution points could not be read.", e);
        }
        for (int i = 0; i < dps.length; i++)
        {
            DistributionPointName dpn = dps[i].getDistributionPoint();
            // look for URIs in fullName
            if (dpn != null)
            {
                if (dpn.getType() == DistributionPointName.FULL_NAME)
                {
                    GeneralName[] genNames = GeneralNames.getInstance(
                        dpn.getName()).getNames();
                    // look for an URI
                    for (int j = 0; j < genNames.length; j++)
                    {
                        if (genNames[j].getTagNo() == GeneralName.uniformResourceIdentifier)
                        {
                            String location = DERIA5String.getInstance(
                                genNames[j].getName()).getString();
                            CertPathValidatorUtilities
                                .addAdditionalStoreFromLocation(location,
                                    pkixParams);
                        }
                    }
                }
            }
        }
    }
}
 

import org.bouncycastle.asn1.x509.DistributionPointName; //导入方法依赖的package包/类
/**
 * Get extension value for CRL Distribution Points as a string.
 * 
 * @param bValue The octet string value
 * @return Extension value as a string
 * @throws IOException If an I/O problem occurs
 */
private String getCrlDistributionPointsStringValue(byte[] bValue)
    throws IOException
{
	CRLDistPoint dps = CRLDistPoint.getInstance(bValue);
	DistributionPoint[] points = dps.getDistributionPoints();

	StringBuilder sb = new StringBuilder();
	sb.append("<ul>");

	for (DistributionPoint point : points)
	{
		DistributionPointName dpn;
		if ((dpn = point.getDistributionPoint()) != null)
		{
			sb.append("<li>");
			switch (dpn.getType())
			{
				case DistributionPointName.FULL_NAME:
					sb.append(RB.getString("CrlDistributionPoint.0.0"));
					sb.append(": ");
					sb.append(getGeneralNamesString((GeneralNames) dpn.getName(), LinkClass.CRL));
					break;
				case DistributionPointName.NAME_RELATIVE_TO_CRL_ISSUER:
					sb.append(RB.getString("CrlDistributionPoint.0.1"));
					sb.append(": ");
					// TODO: need better decode?
					sb.append(stringify(dpn.getName()));
					break;
				default:
					sb.append(RB.getString("UnknownCrlDistributionPointName"));
					sb.append(": ");
					sb.append(stringify(dpn.getName()));
					break;
			}
			sb.append("</li>");
		}

		ReasonFlags flags;
		if ((flags = point.getReasons()) != null)
		{
			sb.append("<li>");
			sb.append(RB.getString("CrlDistributionPoint.1"));
			sb.append(": ");
			// TODO: decode
			sb.append(stringify(flags));
			sb.append("</li>");
		}

		GeneralNames issuer;
		if ((issuer = point.getCRLIssuer()) != null)
		{
			sb.append("<li>");
			sb.append(RB.getString("CrlDistributionPoint.2"));
			sb.append(": ");
			sb.append(getGeneralNamesString(issuer, LinkClass.CRL));
			sb.append("</li>");
		}
	}

	sb.append("</ul>");
	return sb.toString();
}
 

import org.bouncycastle.asn1.x509.DistributionPointName; //导入方法依赖的package包/类
static List<PKIXCRLStore> getAdditionalStoresFromCRLDistributionPoint(CRLDistPoint crldp, Map<GeneralName, PKIXCRLStore> namedCRLStoreMap)
    throws AnnotatedException
{
    if (crldp != null)
    {
        DistributionPoint dps[] = null;
        try
        {
            dps = crldp.getDistributionPoints();
        }
        catch (Exception e)
        {
            throw new AnnotatedException(
                "Distribution points could not be read.", e);
        }
        List<PKIXCRLStore> stores = new ArrayList<PKIXCRLStore>();

        for (int i = 0; i < dps.length; i++)
        {
            DistributionPointName dpn = dps[i].getDistributionPoint();
            // look for URIs in fullName
            if (dpn != null)
            {
                if (dpn.getType() == DistributionPointName.FULL_NAME)
                {
                    GeneralName[] genNames = GeneralNames.getInstance(
                        dpn.getName()).getNames();

                    for (int j = 0; j < genNames.length; j++)
                    {
                        PKIXCRLStore store = namedCRLStoreMap.get(genNames[j]);
                        if (store != null)
                        {
                            stores.add(store);
                        }
                    }
                }
            }
        }

        return stores;
    }
    else
    {
        return Collections.EMPTY_LIST;
    }
}
 

import org.bouncycastle.asn1.x509.DistributionPointName; //导入方法依赖的package包/类
/**
 * Extracts all CRL distribution point URLs from the
 * "CRL Distribution Point" extension in a X.509 certificate. If CRL
 * distribution point extension is unavailable, returns an empty list.
 */
public static List<String> getCrlDistributionPoints(X509Certificate cert) throws CertificateParsingException,
		IOException {
	byte[] crldpExt = cert.getExtensionValue(X509Extension.cRLDistributionPoints.getId());
	if (crldpExt == null) {
		return new ArrayList<String>();
	}
	ASN1InputStream oAsnInStream = null;
	ASN1InputStream oAsnInStream2 = null;
	try {
		oAsnInStream = new ASN1InputStream(new ByteArrayInputStream(crldpExt));
		DERObject derObjCrlDP = oAsnInStream.readObject();
		DEROctetString dosCrlDP = (DEROctetString) derObjCrlDP;
		byte[] crldpExtOctets = dosCrlDP.getOctets();
		oAsnInStream2 = new ASN1InputStream(new ByteArrayInputStream(crldpExtOctets));
		DERObject derObj2 = oAsnInStream2.readObject();
		CRLDistPoint distPoint = CRLDistPoint.getInstance(derObj2);
		List<String> crlUrls = new ArrayList<String>();
		for (DistributionPoint dp : distPoint.getDistributionPoints()) {
			DistributionPointName dpn = dp.getDistributionPoint();
			// Look for URIs in fullName
			if (dpn != null && dpn.getType() == DistributionPointName.FULL_NAME) {
				GeneralName[] genNames = GeneralNames.getInstance(dpn.getName()).getNames();
				// Look for an URI
				for (int j = 0; j < genNames.length; j++) {
					if (genNames[j].getTagNo() == GeneralName.uniformResourceIdentifier) {
						String url = DERIA5String.getInstance(genNames[j].getName()).getString();
						crlUrls.add(url);
					}
				}
			}
		}
		return crlUrls;
	} finally {
		if (oAsnInStream != null) {
			oAsnInStream.close();
		}

		if (oAsnInStream2 != null) {
			oAsnInStream2.close();
		}
	}
}
 

import org.bouncycastle.asn1.x509.DistributionPointName; //导入方法依赖的package包/类
private String getDistributionPointNameString(DistributionPointName distributionPointName, String baseIndent)
		throws IOException {
	// @formatter:off

	/*
	 * DistributionPointName ::= CHOICE {
	 * 		fullname [0] GeneralNames,
	 * 		nameRelativeToCRLIssuer [1] RelativeDistinguishedName
	 * }
	 *
	 * RelativeDistinguishedName ::= SET SIZE (1 .. MAX) OF
	 * AttributeTypeAndValue
	 *
	 * AttributeTypeAndValue ::= ASN1Sequence { type AttributeType, value
	 * AttributeValue }
	 */

	// @formatter: on

	StringBuilder sb = new StringBuilder();

	sb.append(baseIndent);
	sb.append(res.getString("DistributionPointName"));
	sb.append(NEWLINE);

	if (distributionPointName.getType() == DistributionPointName.FULL_NAME) {
		sb.append(baseIndent);
		sb.append(INDENT);
		sb.append(res.getString("DistributionPointFullName"));
		sb.append(NEWLINE);

		GeneralNames generalNames = GeneralNames.getInstance(distributionPointName.getName());

		for (GeneralName generalName : generalNames.getNames()) {
			sb.append(baseIndent);
			sb.append(INDENT);
			sb.append(INDENT);
			sb.append(GeneralNameUtil.toString(generalName));
			sb.append(NEWLINE);
		}
	} else {
		// DistributionPointName.TAG_NAMERELATIVETOCRLISSUER
		sb.append(baseIndent);
		sb.append(INDENT);
		sb.append(res.getString("DistributionPointNameRelativeToCrlIssuer"));
		sb.append(NEWLINE);

		RDN rdn = RDN.getInstance(distributionPointName.getName());

		for (AttributeTypeAndValue attributeTypeAndValue : rdn.getTypesAndValues()) {
			ASN1ObjectIdentifier attributeType = attributeTypeAndValue.getType();
			ASN1Encodable attributeValue = attributeTypeAndValue.getValue();

			String attributeTypeStr = getAttributeTypeString(attributeType);
			String attributeValueStr = getAttributeValueString(attributeType, attributeValue);

			sb.append(baseIndent);
			sb.append(INDENT);
			sb.append(INDENT);
			sb.append(MessageFormat.format("{0}={1}", attributeTypeStr, attributeValueStr));
			sb.append(NEWLINE);
		}
	}

	return sb.toString();
}
 

import org.bouncycastle.asn1.x509.DistributionPointName; //导入方法依赖的package包/类
/**
 * Extracts all CRL distribution point URLs from the
 * "CRL Distribution Point" extension in a X.509 certificate. If CRL
 * distribution point extension is unavailable, returns an empty list.
 */
public static List<String> getCrlDistributionPoints(X509Certificate cert) {

	ASN1InputStream oAsnInStream = null;
	ASN1InputStream oAsnInStream2 = null;
	try {
		byte[] crldpExt = cert.getExtensionValue(Extension.cRLDistributionPoints.getId());
		if (crldpExt == null) {
			List<String> emptyList = new ArrayList<String>();
			return emptyList;
		}
		oAsnInStream = new ASN1InputStream(new ByteArrayInputStream(crldpExt));
		ASN1Primitive derObjCrlDP = oAsnInStream.readObject();
		DEROctetString dosCrlDP = (DEROctetString) derObjCrlDP;
		byte[] crldpExtOctets = dosCrlDP.getOctets();
		oAsnInStream2 = new ASN1InputStream(new ByteArrayInputStream(crldpExtOctets));
		ASN1Primitive derObj2 = oAsnInStream2.readObject();
		CRLDistPoint distPoint = CRLDistPoint.getInstance(derObj2);
		List<String> crlUrls = new ArrayList<String>();
		for (DistributionPoint dp : distPoint.getDistributionPoints()) {
			DistributionPointName dpn = dp.getDistributionPoint();
			// Look for URIs in fullName
			if (dpn != null) {
				if (dpn.getType() == DistributionPointName.FULL_NAME) {
					GeneralName[] genNames = GeneralNames.getInstance(dpn.getName()).getNames();
					// Look for an URI
					for (int j = 0; j < genNames.length; j++) {
						if (genNames[j].getTagNo() == GeneralName.uniformResourceIdentifier) {
							String url = DERIA5String.getInstance(genNames[j].getName()).getString();
							crlUrls.add(url);
						}
					}
				}
			}
		}
		return crlUrls;
	} catch (IOException ex) {
		throw new RuntimeException(ex);
	} finally {
		org.apache.commons.io.IOUtils.closeQuietly(oAsnInStream);
		org.apache.commons.io.IOUtils.closeQuietly(oAsnInStream2);
	}
}
 

import org.bouncycastle.asn1.x509.DistributionPointName; //导入方法依赖的package包/类
/**
 * Gives back the CRL URI meta-data found within the given X509 certificate.
 * 
 * @param certificate
 *            the X509 certificate.
 * @return the CRL URI, or <code>null</code> if the extension is not
 *         present.
 */
public static URI getCrlUri(X509Certificate certificate) {
	byte[] crlDistributionPointsValue = certificate
			.getExtensionValue(Extension.cRLDistributionPoints.getId());
	if (null == crlDistributionPointsValue) {
		return null;
	}
	ASN1Sequence seq;
	try {
		DEROctetString oct;
		oct = (DEROctetString) (new ASN1InputStream(
				new ByteArrayInputStream(crlDistributionPointsValue))
				.readObject());
		seq = (ASN1Sequence) new ASN1InputStream(oct.getOctets())
				.readObject();
	} catch (IOException e) {
		throw new RuntimeException("IO error: " + e.getMessage(), e);
	}
	CRLDistPoint distPoint = CRLDistPoint.getInstance(seq);
	DistributionPoint[] distributionPoints = distPoint
			.getDistributionPoints();
	for (DistributionPoint distributionPoint : distributionPoints) {
		DistributionPointName distributionPointName = distributionPoint
				.getDistributionPoint();
		if (DistributionPointName.FULL_NAME != distributionPointName
				.getType()) {
			continue;
		}
		GeneralNames generalNames = (GeneralNames) distributionPointName
				.getName();
		GeneralName[] names = generalNames.getNames();
		for (GeneralName name : names) {
			if (name.getTagNo() != GeneralName.uniformResourceIdentifier) {
				LOG.debug("not a uniform resource identifier");
				continue;
			}
			DERIA5String derStr = DERIA5String.getInstance(name.getName());
			String str = derStr.getString();
			if (false == str.startsWith("http")) {
				/*
				 * skip ldap:// protocols
				 */
				LOG.debug("not HTTP/HTTPS: " + str);
				continue;
			}
			URI uri = toURI(str);
			return uri;
		}
	}
	return null;
}