eu.europa.esig.dss.cades.signature.CadesLevelBaselineLTATimestampExtractor.java Source code

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/**
 * DSS - Digital Signature Services
 * Copyright (C) 2015 European Commission, provided under the CEF programme
 *
 * This file is part of the "DSS - Digital Signature Services" project.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 */
package eu.europa.esig.dss.cades.signature;

import static eu.europa.esig.dss.OID.id_aa_ATSHashIndex;
import static org.bouncycastle.asn1.pkcs.PKCSObjectIdentifiers.id_aa_ets_certValues;
import static org.bouncycastle.asn1.pkcs.PKCSObjectIdentifiers.id_aa_ets_revocationValues;

import java.util.ArrayList;
import java.util.Collections;
import java.util.Enumeration;
import java.util.HashSet;
import java.util.List;
import java.util.Set;

import org.apache.commons.codec.binary.Base64;
import org.apache.commons.codec.binary.Hex;
import org.bouncycastle.asn1.ASN1Encodable;
import org.bouncycastle.asn1.ASN1EncodableVector;
import org.bouncycastle.asn1.ASN1Integer;
import org.bouncycastle.asn1.ASN1ObjectIdentifier;
import org.bouncycastle.asn1.ASN1OctetString;
import org.bouncycastle.asn1.ASN1Sequence;
import org.bouncycastle.asn1.ASN1Set;
import org.bouncycastle.asn1.DERObjectIdentifier;
import org.bouncycastle.asn1.DEROctetString;
import org.bouncycastle.asn1.DERSequence;
import org.bouncycastle.asn1.DERSet;
import org.bouncycastle.asn1.DERTaggedObject;
import org.bouncycastle.asn1.cms.Attribute;
import org.bouncycastle.asn1.cms.AttributeTable;
import org.bouncycastle.asn1.cms.ContentInfo;
import org.bouncycastle.asn1.cms.SignedData;
import org.bouncycastle.asn1.cms.SignerIdentifier;
import org.bouncycastle.asn1.cms.SignerInfo;
import org.bouncycastle.asn1.x509.AlgorithmIdentifier;
import org.bouncycastle.cms.CMSSignedData;
import org.bouncycastle.cms.SignerInformation;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import eu.europa.esig.dss.DSSASN1Utils;
import eu.europa.esig.dss.DSSException;
import eu.europa.esig.dss.DSSUtils;
import eu.europa.esig.dss.DigestAlgorithm;
import eu.europa.esig.dss.cades.CMSUtils;
import eu.europa.esig.dss.cades.validation.CAdESSignature;
import eu.europa.esig.dss.validation.TimestampToken;
import eu.europa.esig.dss.x509.CertificateToken;

/**
 * Extracts the necessary information to compute the CAdES Archive Timestamp V3.
 *
 *
 *
 *
 *
 */
public class CadesLevelBaselineLTATimestampExtractor {

    private static final Logger LOG = LoggerFactory.getLogger(CadesLevelBaselineLTATimestampExtractor.class);
    public static final DigestAlgorithm DEFAULT_ARCHIVE_TIMESTAMP_HASH_ALGO = DigestAlgorithm.SHA256;
    /**
     * If the algorithm identifier in ATSHashIndex has the default value (DEFAULT_ARCHIVE_TIMESTAMP_HASH_ALGO) then it can be omitted.
     */
    private static final boolean OMIT_ALGORITHM_IDENTIFIER_IF_DEFAULT = true;

    /**
     * The field hashIndAlgorithm contains an identifier of the hash algorithm used to compute the hash values
     * contained in certificatesHashIndex, crlsHashIndex, and unsignedAttrsHashIndex. This algorithm
     * shall be the same as the hash algorithm used for computing the archive time-stamps message imprint.
     *
     * hashIndAlgorithm AlgorithmIdentifier DEFAULT {algorithm id-sha256},
     */
    private DigestAlgorithm hashIndexDigestAlgorithm;

    private final Set<ASN1ObjectIdentifier> excludedAttributesFromAtsHashIndex = new HashSet<ASN1ObjectIdentifier>();
    private CAdESSignature cadesSignature;

    /**
     * This is the default constructor for the {@code CadesLevelBaselineLTATimestampExtractor}.
     *
     * @param cadesSignature {@code CAdESSignature} related to the archive timestamp
     */
    public CadesLevelBaselineLTATimestampExtractor(final CAdESSignature cadesSignature) {

        this.cadesSignature = cadesSignature;
        /* these attribute are validated elsewhere */
        excludedAttributesFromAtsHashIndex.add(id_aa_ets_certValues);
        excludedAttributesFromAtsHashIndex.add(id_aa_ets_revocationValues);
    }

    /**
     * The ats-hash-index unsigned attribute provides an unambiguous imprint of the essential components of a CAdES
     * signature for use in the archive time-stamp (see 6.4.3). These essential components are elements of the following ASN.1
     * SET OF structures: unsignedAttrs, SignedData.certificates, and SignedData.crls.
     *
     * The ats-hash-index attribute value has the ASN.1 syntax ATSHashIndex:
     * ATSHashIndex ::= SEQUENCE {
     * hashIndAlgorithm AlgorithmIdentifier DEFAULT {algorithm id-sha256},
     * certificatesHashIndex SEQUENCE OF OCTET STRING,
     * crlsHashIndex SEQUENCE OF OCTET STRING,
     *
     * @param signerInformation
     * @return
     */
    public Attribute getAtsHashIndex(SignerInformation signerInformation, DigestAlgorithm hashIndexDigestAlgorithm)
            throws DSSException {

        this.hashIndexDigestAlgorithm = hashIndexDigestAlgorithm;
        final AlgorithmIdentifier algorithmIdentifier = getHashIndexDigestAlgorithmIdentifier();
        final ASN1Sequence certificatesHashIndex = getCertificatesHashIndex();
        final ASN1Sequence crLsHashIndex = getCRLsHashIndex();
        final ASN1Sequence unsignedAttributesHashIndex = getUnsignedAttributesHashIndex(signerInformation);
        return getComposedAtsHashIndex(algorithmIdentifier, certificatesHashIndex, crLsHashIndex,
                unsignedAttributesHashIndex);
    }

    /**
     * get the atsHash index for verification of the provided token.
     *
     * @param signerInformation
     * @param timestampToken
     * @return
     */
    public Attribute getVerifiedAtsHashIndex(SignerInformation signerInformation, TimestampToken timestampToken)
            throws DSSException {

        final AlgorithmIdentifier derObjectAlgorithmIdentifier = getAlgorithmIdentifier(timestampToken);
        final ASN1Sequence certificatesHashIndex = getVerifiedCertificatesHashIndex(timestampToken);
        final ASN1Sequence crLsHashIndex = getVerifiedCRLsHashIndex(timestampToken);
        final ASN1Sequence unsignedAttributesHashIndex = getVerifiedUnsignedAttributesHashIndex(signerInformation,
                timestampToken);
        return getComposedAtsHashIndex(derObjectAlgorithmIdentifier, certificatesHashIndex, crLsHashIndex,
                unsignedAttributesHashIndex);
    }

    private Attribute getComposedAtsHashIndex(AlgorithmIdentifier algorithmIdentifiers,
            ASN1Sequence certificatesHashIndex, ASN1Sequence crLsHashIndex,
            ASN1Sequence unsignedAttributesHashIndex) {
        final ASN1EncodableVector vector = new ASN1EncodableVector();
        if (algorithmIdentifiers != null) {
            vector.add(algorithmIdentifiers);
        }
        vector.add(certificatesHashIndex);
        vector.add(crLsHashIndex);
        vector.add(unsignedAttributesHashIndex);
        final ASN1Sequence derSequence = new DERSequence(vector);
        return new Attribute(id_aa_ATSHashIndex, new DERSet(derSequence));
    }

    /**
     * The field certificatesHashIndex is a sequence of octet strings. Each one contains the hash value of one
     * instance of CertificateChoices within certificates field of the root SignedData. A hash value for
     * every instance of CertificateChoices, as present at the time when the corresponding archive time-stamp is
     * requested, shall be included in certificatesHashIndex. No other hash value shall be included in this field.
     *
     * @return
     * @throws eu.europa.esig.dss.DSSException
     */
    private ASN1Sequence getCertificatesHashIndex() throws DSSException {

        final ASN1EncodableVector certificatesHashIndexVector = new ASN1EncodableVector();

        final List<CertificateToken> certificateTokens = cadesSignature.getCertificates();
        for (final CertificateToken certificateToken : certificateTokens) {
            final byte[] encodedCertificate = certificateToken.getEncoded();
            final byte[] digest = DSSUtils.digest(hashIndexDigestAlgorithm, encodedCertificate);
            if (LOG.isDebugEnabled()) {
                LOG.debug("Adding to CertificatesHashIndex DSS-Identifier: {} with hash {}",
                        certificateToken.getDSSId(), Hex.encodeHexString(digest));
            }
            final DEROctetString derOctetStringDigest = new DEROctetString(digest);
            certificatesHashIndexVector.add(derOctetStringDigest);
        }
        return new DERSequence(certificatesHashIndexVector);
    }

    /**
     * The field certificatesHashIndex is a sequence of octet strings. Each one contains the hash value of one
     * instance of CertificateChoices within certificates field of the root SignedData. A hash value for
     * every instance of CertificateChoices, as present at the time when the corresponding archive time-stamp is
     * requested, shall be included in certificatesHashIndex. No other hash value shall be included in this field.
     *
     * @return
     * @throws eu.europa.esig.dss.DSSException
     */
    @SuppressWarnings("unchecked")
    private ASN1Sequence getVerifiedCertificatesHashIndex(TimestampToken timestampToken) throws DSSException {

        final ASN1Sequence certHashes = getCertificatesHashIndex(timestampToken);
        final ArrayList<DEROctetString> certHashesList = Collections.list(certHashes.getObjects());

        final List<CertificateToken> certificates = cadesSignature.getCertificatesWithinSignatureAndTimestamps();
        for (final CertificateToken certificateToken : certificates) {

            final byte[] encodedCertificate = certificateToken.getEncoded();
            final byte[] digest = DSSUtils.digest(hashIndexDigestAlgorithm, encodedCertificate);
            final DEROctetString derOctetStringDigest = new DEROctetString(digest);
            if (certHashesList.remove(derOctetStringDigest)) {
                // attribute present in signature and in timestamp
                LOG.debug("Cert {} present in timestamp", certificateToken.getAbbreviation());
            } else {
                LOG.debug("Cert {} not present in timestamp", certificateToken.getAbbreviation());
            }
        }
        if (!certHashesList.isEmpty()) {
            LOG.error("{} attribute hash in Cert Hashes have not been found in document attributes: {}",
                    certHashesList.size(), certHashesList);
            // return a empty DERSequence to screw up the hash
            return new DERSequence();
        }
        return certHashes;
    }

    /**
     * The field crlsHashIndex is a sequence of octet strings. Each one contains the hash value of one instance of
     * RevocationInfoChoice within crls field of the root SignedData. A hash value for every instance of
     * RevocationInfoChoice, as present at the time when the corresponding archive time-stamp is requested, shall be
     * included in crlsHashIndex. No other hash values shall be included in this field.
     *
     * @return
     * @throws eu.europa.esig.dss.DSSException
     */
    @SuppressWarnings("unchecked")
    private ASN1Sequence getCRLsHashIndex() throws DSSException {

        final ASN1EncodableVector crlsHashIndex = new ASN1EncodableVector();

        final SignedData signedData = SignedData
                .getInstance(cadesSignature.getCmsSignedData().toASN1Structure().getContent());
        final ASN1Set signedDataCRLs = signedData.getCRLs();
        if (signedDataCRLs != null) {
            final Enumeration<ASN1Encodable> crLs = signedDataCRLs.getObjects();
            if (crLs != null) {
                while (crLs.hasMoreElements()) {
                    final ASN1Encodable asn1Encodable = crLs.nextElement();
                    digestAndAddToList(crlsHashIndex, DSSASN1Utils.getDEREncoded(asn1Encodable));
                }
            }
        }

        return new DERSequence(crlsHashIndex);
    }

    private void digestAndAddToList(ASN1EncodableVector crlsHashIndex, byte[] encoded) {
        final byte[] digest = DSSUtils.digest(hashIndexDigestAlgorithm, encoded);
        if (LOG.isDebugEnabled()) {
            LOG.debug("Adding to crlsHashIndex with hash {}", Hex.encodeHexString(digest));
        }
        final DEROctetString derOctetStringDigest = new DEROctetString(digest);
        crlsHashIndex.add(derOctetStringDigest);
    }

    /**
     * The field crlsHashIndex is a sequence of octet strings. Each one contains the hash value of one instance of
     * RevocationInfoChoice within crls field of the root SignedData. A hash value for every instance of
     * RevocationInfoChoice, as present at the time when the corresponding archive time-stamp is requested, shall be
     * included in crlsHashIndex. No other hash values shall be included in this field.
     *
     * @return
     * @throws eu.europa.esig.dss.DSSException
     */
    @SuppressWarnings("unchecked")
    private ASN1Sequence getVerifiedCRLsHashIndex(TimestampToken timestampToken) throws DSSException {

        final ASN1Sequence crlHashes = getCRLHashIndex(timestampToken);
        final ArrayList<DEROctetString> crlHashesList = Collections.list(crlHashes.getObjects());

        final SignedData signedData = SignedData
                .getInstance(cadesSignature.getCmsSignedData().toASN1Structure().getContent());
        final ASN1Set signedDataCRLs = signedData.getCRLs();
        if (signedDataCRLs != null) {
            final Enumeration<ASN1Encodable> crLs = signedDataCRLs.getObjects();
            if (crLs != null) {
                while (crLs.hasMoreElements()) {
                    final ASN1Encodable asn1Encodable = crLs.nextElement();
                    handleRevocationEncoded(crlHashesList, DSSASN1Utils.getDEREncoded(asn1Encodable));
                }
            }
        }

        if (!crlHashesList.isEmpty()) {
            LOG.error("{} attribute hash in CRL Hashes have not been found in document attributes: {}",
                    crlHashesList.size(), crlHashesList);
            // return a empty DERSequence to screw up the hash
            return new DERSequence();
        }

        return crlHashes;
    }

    private void handleRevocationEncoded(ArrayList<DEROctetString> crlHashesList, byte[] ocspHolderEncoded) {

        final byte[] digest = DSSUtils.digest(hashIndexDigestAlgorithm, ocspHolderEncoded);
        final DEROctetString derOctetStringDigest = new DEROctetString(digest);
        if (crlHashesList.remove(derOctetStringDigest)) {
            // attribute present in signature and in timestamp
            if (LOG.isDebugEnabled()) {
                LOG.debug("CRL/OCSP present in timestamp {}", DSSUtils.toHex(derOctetStringDigest.getOctets()));
            }
        } else {
            if (LOG.isDebugEnabled()) {
                LOG.debug("CRL/OCSP not present in timestamp {}", DSSUtils.toHex(derOctetStringDigest.getOctets()));
            }
        }
    }

    private boolean handleCrlEncoded(ArrayList<DEROctetString> crlHashesList, byte[] crlHolderEncoded) {
        final byte[] digest = DSSUtils.digest(hashIndexDigestAlgorithm, crlHolderEncoded);
        final DEROctetString derOctetStringDigest = new DEROctetString(digest);

        return crlHashesList.remove(derOctetStringDigest);
    }

    /**
     * The field unsignedAttrsHashIndex is a sequence of octet strings. Each one contains the hash value of one
     * instance of Attribute within unsignedAttrs field of the SignerInfo. A hash value for every instance of
     * Attribute, as present at the time when the corresponding archive time-stamp is requested, shall be included in
     * unsignedAttrsHashIndex. No other hash values shall be included in this field.
     *
     * @param signerInformation
     * @return
     */
    @SuppressWarnings("unchecked")
    private ASN1Sequence getUnsignedAttributesHashIndex(SignerInformation signerInformation) throws DSSException {

        final ASN1EncodableVector unsignedAttributesHashIndex = new ASN1EncodableVector();
        AttributeTable unsignedAttributes = signerInformation.getUnsignedAttributes();
        final ASN1EncodableVector asn1EncodableVector = unsignedAttributes.toASN1EncodableVector();
        for (int i = 0; i < asn1EncodableVector.size(); i++) {
            final Attribute attribute = (Attribute) asn1EncodableVector.get(i);
            if (!excludedAttributesFromAtsHashIndex.contains(attribute.getAttrType())) {
                final DEROctetString derOctetStringDigest = getAttributeDerOctetStringHash(attribute);
                unsignedAttributesHashIndex.add(derOctetStringDigest);
            }
        }
        return new DERSequence(unsignedAttributesHashIndex);
    }

    /**
     * The field unsignedAttrsHashIndex is a sequence of octet strings. Each one contains the hash value of one
     * instance of Attribute within unsignedAttrs field of the SignerInfo. A hash value for every instance of
     * Attribute, as present at the time when the corresponding archive time-stamp is requested, shall be included in
     * unsignedAttrsHashIndex. No other hash values shall be included in this field.
     *
     * We check that every hash attribute found in the timestamp token is found if the signerInformation.
     *
     * If there is more unsigned attributes in the signerInformation than present in the hash attributes list
     * (and there is at least the archiveTimestampAttributeV3), we don't report any error nor which attributes are signed by the timestamp.
     * If there is some attributes that are not present or altered in the signerInformation, we just return some empty sequence to make
     * sure that the timestamped data will not match. We do not report which attributes hash are present if any.
     *
     * If there is not attribute at all in the archive timestamp hash index, that would means we didn't check anything.
     *
     * @param signerInformation
     * @param timestampToken
     * @return
     */
    @SuppressWarnings("unchecked")
    private ASN1Sequence getVerifiedUnsignedAttributesHashIndex(SignerInformation signerInformation,
            TimestampToken timestampToken) throws DSSException {

        final ASN1Sequence unsignedAttributesHashes = getUnsignedAttributesHashIndex(timestampToken);
        final ArrayList<DEROctetString> timestampUnsignedAttributesHashesList = Collections
                .list(unsignedAttributesHashes.getObjects());

        AttributeTable unsignedAttributes = CMSUtils.getUnsignedAttributes(signerInformation);
        final ASN1EncodableVector asn1EncodableVector = unsignedAttributes.toASN1EncodableVector();
        for (int i = 0; i < asn1EncodableVector.size(); i++) {
            final Attribute attribute = (Attribute) asn1EncodableVector.get(i);
            final DEROctetString derOctetStringDigest = getAttributeDerOctetStringHash(attribute);
            final ASN1ObjectIdentifier attrType = attribute.getAttrType();
            if (timestampUnsignedAttributesHashesList.remove(derOctetStringDigest)) {
                // attribute present in signature and in timestamp
                LOG.debug("Attribute {} present in timestamp", attrType.getId());
            } else {
                LOG.debug("Attribute {} not present in timestamp", attrType.getId());
            }
        }
        if (!timestampUnsignedAttributesHashesList.isEmpty()) {
            LOG.error("{} attribute hash in Timestamp have not been found in document attributes: {}",
                    timestampUnsignedAttributesHashesList.size(), timestampUnsignedAttributesHashesList);
            // return a empty DERSequence to screw up the hash
            return new DERSequence();
        }
        // return the original DERSequence
        return unsignedAttributesHashes;
    }

    private DEROctetString getAttributeDerOctetStringHash(Attribute attribute) throws DSSException {

        final byte[] attributeEncoded = DSSASN1Utils.getDEREncoded(attribute);
        final byte[] digest = DSSUtils.digest(hashIndexDigestAlgorithm, attributeEncoded);
        return new DEROctetString(digest);
    }

    /**
     * Extract the Unsigned Attribute Archive Timestamp Attribute Hash Index from a timestampToken
     *
     * @param timestampToken
     * @return
     */
    private ASN1Sequence getUnsignedAttributesHashIndex(TimestampToken timestampToken) {
        final ASN1Sequence timestampAttributeAtsHashIndexValue = getAtsHashIndex(timestampToken);
        int unsignedAttributesIndex = 2;
        if (timestampAttributeAtsHashIndexValue.size() > 3) {
            unsignedAttributesIndex++;
        }
        return (ASN1Sequence) timestampAttributeAtsHashIndexValue.getObjectAt(unsignedAttributesIndex)
                .toASN1Primitive();
    }

    /**
     * Extract the Unsigned Attribute Archive Timestamp Crl Hash Index from a timestampToken
     *
     * @param timestampToken
     * @return
     */
    private ASN1Sequence getCRLHashIndex(TimestampToken timestampToken) {
        final ASN1Sequence timestampAttributeAtsHashIndexValue = getAtsHashIndex(timestampToken);
        int crlIndex = 1;
        if (timestampAttributeAtsHashIndexValue.size() > 3) {
            crlIndex++;
        }
        return (ASN1Sequence) timestampAttributeAtsHashIndexValue.getObjectAt(crlIndex).toASN1Primitive();
    }

    /**
     * Extract the Unsigned Attribute Archive Timestamp Cert Hash Index from a timestampToken
     *
     * @param timestampToken
     * @return
     */
    private ASN1Sequence getCertificatesHashIndex(TimestampToken timestampToken) {

        final ASN1Sequence timestampAttributeAtsHashIndexValue = getAtsHashIndex(timestampToken);
        int certificateIndex = 0;
        if (timestampAttributeAtsHashIndexValue.size() > 3) {
            certificateIndex++;
        }
        return (ASN1Sequence) timestampAttributeAtsHashIndexValue.getObjectAt(certificateIndex).toASN1Primitive();
    }

    /**
     * Extract the Unsigned Attribute Archive Timestamp Cert Hash Index from a timestampToken
     *
     * @param timestampToken
     * @return
     */
    private AlgorithmIdentifier getAlgorithmIdentifier(final TimestampToken timestampToken) {

        final ASN1Sequence timestampAttributeAtsHashIndexValue = getAtsHashIndex(timestampToken);
        if (timestampAttributeAtsHashIndexValue.size() > 3) {

            final int algorithmIndex = 0;
            final ASN1Encodable asn1Encodable = timestampAttributeAtsHashIndexValue.getObjectAt(algorithmIndex);
            if (asn1Encodable instanceof ASN1Sequence) {

                final ASN1Sequence asn1Sequence = (ASN1Sequence) asn1Encodable;
                final ASN1ObjectIdentifier asn1ObjectIdentifier = (ASN1ObjectIdentifier) asn1Sequence
                        .getObjectAt(0);
                hashIndexDigestAlgorithm = DigestAlgorithm.forOID(asn1ObjectIdentifier.getId());
                return AlgorithmIdentifier.getInstance(asn1Sequence);
            } else if (asn1Encodable instanceof DERObjectIdentifier) {

                // TODO (16/11/2014): The relevance and usefulness of the test case must be checked (do the signatures like this exist?)
                ASN1ObjectIdentifier derObjectIdentifier = ASN1ObjectIdentifier.getInstance(asn1Encodable);
                hashIndexDigestAlgorithm = DigestAlgorithm.forOID(derObjectIdentifier.getId());
                return new AlgorithmIdentifier(derObjectIdentifier);
            }
        }
        hashIndexDigestAlgorithm = DEFAULT_ARCHIVE_TIMESTAMP_HASH_ALGO;
        return null;
    }

    /**
     * @param timestampToken
     * @return the content of SignedAttribute: ATS-hash-index unsigned attribute {itu-t(0) identified-organization(4) etsi(0) electronic-signature-standard(1733) attributes(2) 5}
     */
    private ASN1Sequence getAtsHashIndex(TimestampToken timestampToken) {
        final AttributeTable timestampTokenUnsignedAttributes = timestampToken.getUnsignedAttributes();
        final Attribute atsHashIndexAttribute = timestampTokenUnsignedAttributes.get(id_aa_ATSHashIndex);
        final ASN1Set attrValues = atsHashIndexAttribute.getAttrValues();
        return (ASN1Sequence) attrValues.getObjectAt(0).toASN1Primitive();
    }

    private AlgorithmIdentifier getHashIndexDigestAlgorithmIdentifier() {
        if (OMIT_ALGORITHM_IDENTIFIER_IF_DEFAULT
                && hashIndexDigestAlgorithm.getOid().equals(DEFAULT_ARCHIVE_TIMESTAMP_HASH_ALGO.getOid())) {
            return null;
        } else {
            return DSSASN1Utils.getAlgorithmIdentifier(hashIndexDigestAlgorithm);
        }
    }

    public byte[] getArchiveTimestampDataV3(SignerInformation signerInformation, Attribute atsHashIndexAttribute,
            byte[] originalDocument, DigestAlgorithm digestAlgorithm) throws DSSException {

        final CMSSignedData cmsSignedData = cadesSignature.getCmsSignedData();
        final byte[] encodedContentType = getEncodedContentType(cmsSignedData); // OID
        final byte[] signedDataDigest = DSSUtils.digest(digestAlgorithm, originalDocument);
        final byte[] encodedFields = getSignedFields(signerInformation);
        final byte[] encodedAtsHashIndex = DSSASN1Utils
                .getDEREncoded(atsHashIndexAttribute.getAttrValues().getObjectAt(0));
        /** The input for the archive-time-stamp-v3s message imprint computation shall be the concatenation (in the
         * order shown by the list below) of the signed data hash (see bullet 2 below) and certain fields in their binary encoded
         * form without any modification and including the tag, length and value octets:
         */
        final byte[] dataToTimestamp = DSSUtils.concatenate(encodedContentType, signedDataDigest, encodedFields,
                encodedAtsHashIndex);
        if (LOG.isDebugEnabled()) {
            LOG.debug("eContentType={}", Hex.encodeHexString(encodedContentType));
            LOG.debug("signedDataDigest={}", Hex.encodeHexString(signedDataDigest));
            LOG.debug("encodedFields=see above");
            LOG.debug("encodedAtsHashIndex={}", Hex.encodeHexString(encodedAtsHashIndex));
            // LOG.debug("Archive Timestamp Data v3 is: {}", Hex.encodeHexString(dataToTimestamp));
        }
        return dataToTimestamp;
    }

    /**
     * 1) The SignedData.encapContentInfo.eContentType.
     *
     * @param cmsSignedData
     * @return cmsSignedData.getSignedContentTypeOID() as DER encoded
     */
    private byte[] getEncodedContentType(final CMSSignedData cmsSignedData) {
        final ContentInfo contentInfo = cmsSignedData.toASN1Structure();
        final SignedData signedData = SignedData.getInstance(contentInfo.getContent());
        return DSSASN1Utils.getDEREncoded(signedData.getEncapContentInfo().getContentType());
    }

    /**
     * 3) Fields version, sid, digestAlgorithm, signedAttrs, signatureAlgorithm, and
     * signature within the SignedData.signerInfoss item corresponding to the signature being archive
     * time-stamped, in their order of appearance.
     *
     * @param signerInformation
     * @return
     */
    private byte[] getSignedFields(final SignerInformation signerInformation) {

        final SignerInfo signerInfo = signerInformation.toASN1Structure();
        final ASN1Integer version = signerInfo.getVersion();
        final SignerIdentifier sid = signerInfo.getSID();
        final AlgorithmIdentifier digestAlgorithm = signerInfo.getDigestAlgorithm();
        final DERTaggedObject signedAttributes = CMSUtils.getDERSignedAttributes(signerInformation);
        final AlgorithmIdentifier digestEncryptionAlgorithm = signerInfo.getDigestEncryptionAlgorithm();
        final ASN1OctetString encryptedDigest = signerInfo.getEncryptedDigest();

        final byte[] derEncodedVersion = DSSASN1Utils.getDEREncoded(version);
        final byte[] derEncodedSid = DSSASN1Utils.getDEREncoded(sid);
        final byte[] derEncodedDigestAlgorithm = DSSASN1Utils.getDEREncoded(digestAlgorithm);
        final byte[] derEncodedSignedAttributes = DSSASN1Utils.getDEREncoded(signedAttributes);
        final byte[] derEncodedDigestEncryptionAlgorithm = DSSASN1Utils.getDEREncoded(digestEncryptionAlgorithm);
        final byte[] derEncodedEncryptedDigest = DSSASN1Utils.getDEREncoded(encryptedDigest);
        if (LOG.isDebugEnabled()) {

            LOG.debug("getSignedFields Version={}", Base64.decodeBase64(derEncodedVersion));
            LOG.debug("getSignedFields Sid={}", Base64.decodeBase64(derEncodedSid));
            LOG.debug("getSignedFields DigestAlgorithm={}", Base64.decodeBase64(derEncodedDigestAlgorithm));
            LOG.debug("getSignedFields SignedAttributes={}", Hex.encodeHexString(derEncodedSignedAttributes));
            LOG.debug("getSignedFields DigestEncryptionAlgorithm={}",
                    Base64.decodeBase64(derEncodedDigestEncryptionAlgorithm));
            LOG.debug("getSignedFields EncryptedDigest={}", Base64.decodeBase64(derEncodedEncryptedDigest));
        }
        final byte[] concatenatedArrays = DSSUtils.concatenate(derEncodedVersion, derEncodedSid,
                derEncodedDigestAlgorithm, derEncodedSignedAttributes, derEncodedDigestEncryptionAlgorithm,
                derEncodedEncryptedDigest);
        return concatenatedArrays;
    }
}