http://www.bouncycastle.org/java.html: The Bouncy Castle Java APIs for CMS, PKCS, EAC, TSP, CMP, CRMF, OCSP, and certificate generation. This jar contains APIs for JDK 1.5 to JDK 1.8. The APIs can be used in conjunction with a JCE/JCA provider such as the one provided with the Bouncy Castle Cryptography APIs.
  • The Legion of the Bouncy Castle Inc. 
package org.bouncycastle.tsp.cms;

import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.URI;
import java.net.URISyntaxException;

import org.bouncycastle.asn1.ASN1InputStream;
import org.bouncycastle.asn1.DERIA5String;
import org.bouncycastle.asn1.cms.AttributeTable;
import org.bouncycastle.asn1.cms.CMSObjectIdentifiers;
import org.bouncycastle.asn1.cms.ContentInfo;
import org.bouncycastle.asn1.cms.Evidence;
import org.bouncycastle.asn1.cms.TimeStampAndCRL;
import org.bouncycastle.asn1.cms.TimeStampTokenEvidence;
import org.bouncycastle.asn1.cms.TimeStampedData;
import org.bouncycastle.cms.CMSException;
import org.bouncycastle.operator.DigestCalculator;
import org.bouncycastle.operator.DigestCalculatorProvider;
import org.bouncycastle.operator.OperatorCreationException;
import org.bouncycastle.tsp.TimeStampToken;

public class CMSTimeStampedData
{
    private TimeStampedData timeStampedData;
    private ContentInfo contentInfo;
    private TimeStampDataUtil util;

    public CMSTimeStampedData(ContentInfo contentInfo)
    {
        this.initialize(contentInfo);
    }

    public CMSTimeStampedData(InputStream in)
        throws IOException
    {
        try
        {
            initialize(ContentInfo.getInstance(new ASN1InputStream(in).readObject()));
        }
        catch (ClassCastException e)
        {
            throw new IOException("Malformed content: " + e);
        }
        catch (IllegalArgumentException e)
        {
            throw new IOException("Malformed content: " + e);
        }
    }

    public CMSTimeStampedData(byte[] baseData)
        throws IOException
    {
        this(new ByteArrayInputStream(baseData));
    }

    private void initialize(ContentInfo contentInfo)
    {
        this.contentInfo = contentInfo;

        if (CMSObjectIdentifiers.timestampedData.equals(contentInfo.getContentType()))
        {
            this.timeStampedData = TimeStampedData.getInstance(contentInfo.getContent());
        }
        else
        {
            throw new IllegalArgumentException("Malformed content - type must be " + CMSObjectIdentifiers.timestampedData.getId());
        }

        util = new TimeStampDataUtil(this.timeStampedData);
    }

    public byte[] calculateNextHash(DigestCalculator calculator)
        throws CMSException
    {
        return util.calculateNextHash(calculator);
    }

    
Return a new timeStampedData object with the additional token attached.

Throws:
  • CMSException – 
/**
     * Return a new timeStampedData object with the additional token attached.
     *
     * @throws CMSException
     */
    public CMSTimeStampedData addTimeStamp(TimeStampToken token)
        throws CMSException
    {
        TimeStampAndCRL[] timeStamps = util.getTimeStamps();
        TimeStampAndCRL[] newTimeStamps = new TimeStampAndCRL[timeStamps.length + 1];

        System.arraycopy(timeStamps, 0, newTimeStamps, 0, timeStamps.length);

        newTimeStamps[timeStamps.length] = new TimeStampAndCRL(token.toCMSSignedData().toASN1Structure());

        return new CMSTimeStampedData(new ContentInfo(CMSObjectIdentifiers.timestampedData, new TimeStampedData(timeStampedData.getDataUri(), timeStampedData.getMetaData(), timeStampedData.getContent(), new Evidence(new TimeStampTokenEvidence(newTimeStamps)))));
    }

    public byte[] getContent()
    {
        if (timeStampedData.getContent() != null)
        {
            return timeStampedData.getContent().getOctets();
        }

        return null;
    }

    public URI getDataUri()
        throws URISyntaxException
    {
        DERIA5String dataURI = this.timeStampedData.getDataUri();

        if (dataURI != null)
        {
            return new URI(dataURI.getString());
        }

        return null;
    }

    public String getFileName()
    {
        return util.getFileName();
    }

    public String getMediaType()
    {
        return util.getMediaType();
    }

    public AttributeTable getOtherMetaData()
    {
        return util.getOtherMetaData();
    }

    public TimeStampToken[] getTimeStampTokens()
        throws CMSException
    {
        return util.getTimeStampTokens();
    }

    
Initialise the passed in calculator with the MetaData for this message, if it is
required as part of the initial message imprint calculation.

Params:
  • calculator – the digest calculator to be initialised.
Throws:
  • CMSException – if the MetaData is required and cannot be processed
/**
     * Initialise the passed in calculator with the MetaData for this message, if it is
     * required as part of the initial message imprint calculation.
     *
     * @param calculator the digest calculator to be initialised.
     * @throws CMSException if the MetaData is required and cannot be processed
     */
    public void initialiseMessageImprintDigestCalculator(DigestCalculator calculator)
        throws CMSException
    {
        util.initialiseMessageImprintDigestCalculator(calculator);
    }

    
Returns an appropriately initialised digest calculator based on the message imprint algorithm
described in the first time stamp in the TemporalData for this message. If the metadata is required
to be included in the digest calculation, the returned calculator will be pre-initialised.

Params:
  • calculatorProvider –  a provider of DigestCalculator objects.
Throws:
Returns:an initialised digest calculator.
/**
     * Returns an appropriately initialised digest calculator based on the message imprint algorithm
     * described in the first time stamp in the TemporalData for this message. If the metadata is required
     * to be included in the digest calculation, the returned calculator will be pre-initialised.
     *
     * @param calculatorProvider  a provider of DigestCalculator objects.
     * @return an initialised digest calculator.
     * @throws OperatorCreationException if the provider is unable to create the calculator.
     */
    public DigestCalculator getMessageImprintDigestCalculator(DigestCalculatorProvider calculatorProvider)
        throws OperatorCreationException
    {
        return util.getMessageImprintDigestCalculator(calculatorProvider);
    }

    
Validate the digests present in the TimeStampTokens contained in the CMSTimeStampedData.

Params:
  • calculatorProvider – provider for digest calculators
  • dataDigest – the calculated data digest for the message
Throws:
/**
     * Validate the digests present in the TimeStampTokens contained in the CMSTimeStampedData.
     *
     * @param calculatorProvider provider for digest calculators
     * @param dataDigest the calculated data digest for the message
     * @throws ImprintDigestInvalidException if an imprint digest fails to compare
     * @throws CMSException  if an exception occurs processing the message.
     */
    public void validate(DigestCalculatorProvider calculatorProvider, byte[] dataDigest)
        throws ImprintDigestInvalidException, CMSException
    {
        util.validate(calculatorProvider, dataDigest);
    }

    
Validate the passed in timestamp token against the tokens and data present in the message.

Params:
  • calculatorProvider – provider for digest calculators
  • dataDigest – the calculated data digest for the message.
  • timeStampToken –  the timestamp token of interest.
Throws:
/**
     * Validate the passed in timestamp token against the tokens and data present in the message.
     *
     * @param calculatorProvider provider for digest calculators
     * @param dataDigest the calculated data digest for the message.
     * @param timeStampToken  the timestamp token of interest.
     * @throws ImprintDigestInvalidException if the token is not present in the message, or an imprint digest fails to compare.
     * @throws CMSException if an exception occurs processing the message.
     */
    public void validate(DigestCalculatorProvider calculatorProvider, byte[] dataDigest, TimeStampToken timeStampToken)
        throws ImprintDigestInvalidException, CMSException
    {
        util.validate(calculatorProvider, dataDigest, timeStampToken);
    }

    public byte[] getEncoded()
        throws IOException
    {
        return contentInfo.getEncoded();
    }
}