Android™

Sign a File to Create a .p7s (Detached Signature)

See more Encryption Examples

_LANGUAGE_ example to create a detached signature file (.p7s) for any type file. The signature can be verified by calling VerifyP7S and passing the original filename and the .p7s filename. 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.

    CkCrypt2 crypt = new CkCrypt2();

    // Use a digital certificate and private key from a PFX file (.pfx or .p12).
    String signingCertSubject = "Acme Inc";
    String pfxFilename = "/Users/chilkat/testData/pfx/acme.pfx";
    String pfxPassword = "test123";

    CkCertStore certStore = new CkCertStore();
    success = certStore.LoadPfxFile(pfxFilename,pfxPassword);
    if (success != true) {
        Log.i(TAG, certStore.lastErrorText());
        return;
        }

    CkJsonObject jsonCN = new CkJsonObject();
    jsonCN.UpdateString("CN",signingCertSubject);

    CkCert cert = new CkCert();
    success = certStore.FindCert(jsonCN,cert);
    if (success == false) {
        Log.i(TAG, "Failed to find certificate by subject common name.");
        return;
        }

    // Tell the crypt component to use this cert.
    success = crypt.SetSigningCert(cert);

    // We can sign any type of file, creating a .p7s as output:
    String inFile = "/Users/chilkat/testData/pdf/sample.pdf";
    String sigFile = "/Users/chilkat/testData/p7s/sample.p7s";

    success = crypt.CreateP7S(inFile,sigFile);
    if (success == false) {
        Log.i(TAG, crypt.lastErrorText());
        return;
        }

    success = crypt.VerifyP7S(inFile,sigFile);
    if (success == false) {
        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."
  }
}