Download - Svetlin Nakov

* and displays the verification results. The received document, certificate and
* signature are taken from the member variables mReceivedFileData, mCertificate
* and mSignature respectively.
*/
private void verifyReceivedSignature()
throws IOException {
mOut.println("Digital signature status: ");
try {
boolean signatureValid = DigitalSignatureUtils.verifyDocumentSignature(
mReceivedFileData, mCertificate, mSignature);
if (signatureValid)
mOut.println("Signature is verified to be VALID.");
else
mOut.println("Signature is INVALID!");
} catch (Exception e) {
e.printStackTrace();
mOut.println("Signature verification failed due to exception: " +
e.toString());
}
mOut.println("");
}
/**
* Displays information about given certificate. This information includes the
* certificate subject distinguished name and its purposes (public key usages).
*/
private void displayCertificate(X509Certificate aCertificate)
throws IOException {
String certificateSubject = aCertificate.getSubjectDN().toString();
mOut.println("Certificate subject: " + certificateSubject + " ");
}
boolean[] certKeyUsage = aCertificate.getKeyUsage();
mOut.println("Certificate purposes (public key usages): ");
if (certKeyUsage != null) {
if (certKeyUsage[KEY_USAGE_DIGITAL_SIGNATURE])
mOut.println("[digitalSignature] - verify digital signatures ");
if (certKeyUsage[KEY_USAGE_NON_REPUDIATION])
mOut.println("[nonRepudiation] - verify non-repudiation ");
if (certKeyUsage[KEY_USAGE_KEY_ENCIPHERMENT])
mOut.println("[keyEncipherment] - encipher keys for transport");
if (certKeyUsage[KEY_USAGE_DATA_ENCIPHERMENT])
mOut.println("[dataEncipherment] - encipher user data ");
if (certKeyUsage[KEY_USAGE_KEY_AGREEMENT])
mOut.println("[keyAgreement] - use for key agreement ");
if (certKeyUsage[KEY_USAGE_CERT_SIGN])
mOut.println("[keyCertSign] - verify signatures on certs ");
if (certKeyUsage[KEY_USAGE_CRL_SIGN])
mOut.println("[cRLSign] - verify signatures on CRLs ");
if (certKeyUsage[KEY_USAGE_ENCIPHER_ONLY])
mOut.println("[encipherOnly] - encipher during key agreement ");
if (certKeyUsage[KEY_USAGE_DECIPHER_ONLY])
mOut.println("[decipherOnly] - decipher during key agreement ");
} else {
mOut.println("[No purposes defined] ");
}
/**
* Verifies received certificate directly and displays the verification results.
* The certificate for verification is taken form mCertificate member variable.
* Trusted certificates are taken from the CERTS_FOR_DIRECT_VALIDATION_DIR
* directory. This directory should be relative to the Web application root
* directory and should contain only .CER files (DER-encoded X.509 cert.).
*/
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