(Android™) Create a CAdES-T Signature

Demonstrates how to create a signature with an external timestamp that certifies the time of signing. This requires an online TSA (Time Stamping Authority) service that is capable of producing RFC 3161 compliant timestamps.

Note: This example requires Chilkat v9.5.0.78 or greater.

Chilkat Android™ Downloads Android™ Java Libraries Android C/C++ Libraries

// Important: Don't forget to include the call to System.loadLibrary
// as shown at the bottom of this code sample.
package com.test;

import android.app.Activity;
import com.chilkatsoft.*;

import android.widget.TextView;
import android.os.Bundle;

public class SimpleActivity extends Activity {

  private static final String TAG = "Chilkat";

  // Called when the activity is first created.
  @Override
  public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    // This example requires the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    CkCrypt2 crypt = new CkCrypt2();

    // This example will use a certificate + private key from a .pfx/.p12 file.
    // On Windows systems, it is also possible to use certs on smartcards/usb tokens or certs pre-installed in the Windows registry.
    CkCert cert = new CkCert();

    String pfxPath = "qa_data/pfx/myCertAndKey.p12";
    String pfxPassword = "test123";

    boolean success = cert.LoadPfxFile(pfxPath,pfxPassword);
    if (success != true) {
        Log.i(TAG, cert.lastErrorText());
        return;
        }

    success = crypt.SetSigningCert(cert);

    // Use SHA-256 rather than the default of SHA-1
    crypt.put_HashAlgorithm("sha256");

    // Create JSON that tells Chilkat what signing attributes to include:
    CkJsonObject attrs = new CkJsonObject();
    attrs.UpdateBool("contentType",true);
    attrs.UpdateBool("signingTime",true);
    attrs.UpdateBool("messageDigest",true);
    attrs.UpdateBool("signingCertificateV2",true);

    // A CAdES-T signature is one that includes a timestampToken created by an online TSA (time stamping authority).
    // We must include the TSA's URL, as well as a few options to indicate what is desired.
    // Except for the TSA URL, the options shown here are typically what you would need.
    attrs.UpdateBool("timestampToken.enabled",true);
    attrs.UpdateString("timestampToken.tsaUrl","https://freetsa.org/tsr");
    attrs.UpdateBool("timestampToken.addNonce",false);
    attrs.UpdateBool("timestampToken.requestTsaCert",true);
    attrs.UpdateString("timestampToken.hashAlg","sha256");

    crypt.put_SigningAttributes(attrs.emit());

    String inFile = "qa_data/json/sample.json";
    String outFile = "qa_output/sample_cades_t.p7m";

    // This creates the CAdES-T signature.  During the signature creation, it
    // communicates with the TSA to get a timestampToken.
    success = crypt.CreateP7M(inFile,outFile);
    if (success != true) {
        Log.i(TAG, crypt.lastErrorText());
        return;
        }

    Log.i(TAG, "Success.");

  }

  static {
      System.loadLibrary("chilkat");

      // Note: If the incorrect library name is passed to System.loadLibrary,
      // then you will see the following error message at application startup:
      //"The application <your-application-name> has stopped unexpectedly. Please try again."
  }
}