Android™

Examine KeyInfo Certificate in XML Signature

See more XML Digital Signatures Examples

This example loads signed XML and gets the signing certificate, assuming the certificate is contained in X509Certificate within the KeyInfo. Android™

// 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);

    boolean success = false;

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

    CkXmlDSig dsig = new CkXmlDSig();
    CkStringBuilder sbXml = new CkStringBuilder();

    success = sbXml.LoadFile("c:/aaworkarea/elias/3/face_f09006808443a699d1b.xml","utf-8");
    if (success != true) {
        Log.i(TAG, "Failed to load XML file.");
        return;
        }

    success = dsig.LoadSignatureSb(sbXml);
    if (success != true) {
        Log.i(TAG, dsig.lastErrorText());
        return;
        }

    // Get the KeyInfo XML.
    CkXml xmlKeyInfo = dsig.GetKeyInfo();
    if (dsig.get_LastMethodSuccess() != true) {
        Log.i(TAG, dsig.lastErrorText());
        return;
        }

    Log.i(TAG, xmlKeyInfo.getXml());
    Log.i(TAG, "----");

    // Assuming the X509Certificate is in the KeyInfo, it will look like this:

    //   <ds:KeyInfo Id="...">
    //     <ds:KeyValue>
    //     ...  
    //     <ds:X509Data>
    //       <ds:X509Certificate>MIIHAz...</ds:X509Certificate>
    //     </ds:X509Data>
    //   </ds:KeyInfo>
    String certBase64 = xmlKeyInfo.getChildContent("*:X509Data|*:X509Certificate");
    if (xmlKeyInfo.get_LastMethodSuccess() != true) {
        Log.i(TAG, "No X509Certificate found in the KeyInfo.");
        return;
        }

    // Load a certificate object w/ the base64.
    CkCert cert = new CkCert();
    success = cert.LoadFromBase64(certBase64);
    if (success != true) {
        Log.i(TAG, cert.lastErrorText());
        return;
        }

    // Examine the cert..
    Log.i(TAG, "SubjectDN: " + cert.subjectDN());
    Log.i(TAG, "IssuerDN: " + cert.issuerDN());
    Log.i(TAG, "SerialNumber as Decimal: " + cert.serialDecimal());


  }

  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."
  }
}