/**
* method for JSP to create valid TimeStampRequest
*
* @param file
* @param tsr
* @return
*/
public TimeStampRequest createCorrespondingTSQ(byte[] file, TimeStampResponse tsr) {
// get hash algorithm
ASN1ObjectIdentifier algID =
tsr.getTimeStampToken().getTimeStampInfo().getMessageImprintAlgOID();
GeneralDigest digestAlgorithm = getDigestAlg(algID);
logger.info(
"The timestamp's algorithm was recognized as {}.", digestAlgorithm.getAlgorithmName());
// create new hashed request
byte[] digest = calculateMessageDigest(file, digestAlgorithm);
TimeStampRequest tsq = getTSRequest(digest, algID);
return tsq;
}
/**
* prints details of received TimeStamp
*
* @param tsr {@link TimeStampResponse}
*/
private void logResponse(final TimeStampResponse tsr) {
logger.info("Timestamp: {}", tsr.getTimeStampToken().getTimeStampInfo().getGenTime());
logger.info("TSA: {}", tsr.getTimeStampToken().getTimeStampInfo().getTsa());
logger.info("Serial number: {}", tsr.getTimeStampToken().getTimeStampInfo().getSerialNumber());
logger.info("Policy: {}", tsr.getTimeStampToken().getTimeStampInfo().getPolicy());
}
/**
* Main method for validating files with stamps. It serves as an example of whole process in one
* go.
*
* @param originalFile
* @param timeStamp
* @throws IOException
* @throws TSPException
* @throws CertificateException
* @throws CertificateEncodingException
* @throws OperatorCreationException
*/
public void verify(InputStream originalFile, InputStream timeStamp)
throws IOException, TSPException, CertificateException, CertificateEncodingException,
OperatorCreationException {
logger.entry();
// open files
byte[] file = getBytesFromInputStream(originalFile);
TimeStampResponse tsr = parseTSR(timeStamp);
logger.info("The timestamp was sucessfully opened.");
logResponse(tsr);
// get hash algorithm
ASN1ObjectIdentifier algID =
tsr.getTimeStampToken().getTimeStampInfo().getMessageImprintAlgOID();
GeneralDigest digestAlgorithm = getDigestAlg(algID);
logger.info(
"The timestamp's algorithm was recognized as {}.", digestAlgorithm.getAlgorithmName());
// create new hashed request
byte[] digest = calculateMessageDigest(file, digestAlgorithm);
TimeStampRequest tsq = getTSRequest(digest, algID);
logger.info(
"The timestamp fits the file (the file was not changed), now verifying certificates..");
InputStream is = null;
if (is == null) {
throw new UnsupportedOperationException(
"Timestamp fits the file (the file was not changed), certificate not implemented yet.");
}
// <editor-fold defaultstate="collapsed" desc="varianta 1 - ze souboru">
CertificateFactory factory;
X509Certificate cert;
try {
factory = CertificateFactory.getInstance("X.509");
cert = (X509Certificate) factory.generateCertificate(null); // TODO: get inputstream
} catch (CertificateException e) {
logger.catching(e);
throw e;
}
// RSA Signature processing with BC
X509CertificateHolder holder;
SignerInformationVerifier siv;
try {
holder = new X509CertificateHolder(cert.getEncoded());
siv =
new BcRSASignerInfoVerifierBuilder(
new DefaultCMSSignatureAlgorithmNameGenerator(),
new DefaultSignatureAlgorithmIdentifierFinder(),
new DefaultDigestAlgorithmIdentifierFinder(), new BcDigestCalculatorProvider())
.build(holder);
} catch (CertificateEncodingException | OperatorCreationException e) {
logger.catching(e);
throw e;
}
// Signature processing with JCA and other provider
// X509CertificateHolder holderJca = new JcaX509CertificateHolder(cert);
// SignerInformationVerifier sivJca = new
// JcaSimpleSignerInfoVerifierBuilder().setProvider("anotherprovider").build(holderJca);
try {
tsr.getTimeStampToken().validate(siv);
} catch (TSPException e) {
logger.catching(e);
throw e;
}
/* konec varianty 1 */
// </editor-fold>
// <editor-fold defaultstate="collapsed" desc="varianta 2 - z razitka">
/*/ get certificates
CollectionStore certs = (CollectionStore) tst.getCertificates();
SignerInformationStore signers = tst.toCMSSignedData().getSignerInfos();
int certsCount = 0;
for (Iterator it = certs.iterator(); it.hasNext();) {
certsCount++; // stupid hack to get actual number of certificates
}
if (certsCount < 1) {
logger.error("No certificate found.");
return;
}
for (SignerInformation signer : signers) {
Collection<X509Certificate> col = certs.getMatches(signer.getSID());
X509Certificate[] signerCerts = new X509Certificate[0];
col.toArray(signerCerts);
if (signerCerts.length != 1) {
logger.error("Expected only one certificate per signer.");
return;
}
try {
signerCerts[0].checkValidity();
} catch (CertificateExpiredException | CertificateNotYetValidException ex) {
java.util.logging.Logger.getLogger(TSAConnector.class.getName()).log(Level.SEVERE, null, ex);
}
// signer.verify(signerCerts[0]); // should verify that the timestamp is signed correctly
}
/* konec varianty 2 */
// </editor-fold>
logger.info("All certificates successfully verified, the timestamp is trusted.");
logger.exit();
}