(Android™) Sign Mexico Pedimento

Add a signature to a Mexico pedimento file.

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.

    boolean success;

    // This is the contents before signing:

    // 500|1|3621|4199800|400||
    // 601|3621|4199800|400|IN|1||EKU9003173C9|EKU9003173C9FRNN09|1||
    // 507|4199800|IM|2006-7888">
    // 507|4199800|MS|2">
    // 800|4199800|1">
    // 801|M3621037.222|1|5|011|

    // This is the contents after signing

    // 500|1|3621|4199800|400||
    // 601|3621|4199800|400|IN|1||EKU9003173C9|EKU9003173C9FRNN09|1||
    // 507|4199800|IM|2006-7888">
    // 507|4199800|MS|2">
    // 800|4199800|1|fhP2Ker54D2+3+UZch23F0E72 .... 9qNSPIuAqpj524qLZbbA==|30001000000500003416|
    // 801|M3621037.222|1|5|011|

    // First create the text to be signed.
    boolean bCRLF = true;
    CkStringBuilder sb = new CkStringBuilder();
    // Use CRLF line endings.
    sb.AppendLine("500|1|3621|4199800|400||",bCRLF);
    sb.AppendLine("601|3621|4199800|400|IN|1||EKU9003173C9|EKU9003173C9FRNN09|1||",bCRLF);
    sb.AppendLine("507|4199800|IM|2006-7888">",bCRLF);
    sb.AppendLine("507|4199800|MS|2">",bCRLF);

    // Generate the MD5 hash of what we have so far..
    String md5_base64 = sb.getHash("md5","base64","utf-8");
    Log.i(TAG, "MD5 hash = " + md5_base64);

    // Complete the original file.
    // After signing, we'll update the BASE64_SIGNATURE and CERT_SERIAL
    sb.AppendLine("800|4199800|1|BASE64_SIGNATURE|CERT_SERIAL|",bCRLF);
    sb.AppendLine("801|M3621037.222|1|5|011|",bCRLF);

    // We're going to sign the MD5 hash using the private key.
    CkPrivateKey privKey = new CkPrivateKey();
    success = privKey.LoadAnyFormatFile("qa_data/certs/mexico_test/Certificados_de_Prueba/Certificados_Pruebas/Personas Morales/EKU9003173C9_20230517223532/CSD_EKU9003173C9_20230517223903/CSD_Sucursal_1_EKU9003173C9_20230517_223850.key","12345678a");
    if (success == false) {
        Log.i(TAG, privKey.lastErrorText());
        return;
        }

    // Generate the ASN.1 to be signed.

    // <sequence>
    //     <sequence>
    //         <oid>1.2.840.113549.2.5</oid>
    //         <null/>
    //     </sequence>
    //     <octets>SwxHfaJhG+N3pPqay6UzVA==</octets>
    // </sequence>

    CkXml xml = new CkXml();
    xml.put_Tag("sequence");
    xml.UpdateChildContent("sequence|oid","1.2.840.113549.2.5");
    xml.UpdateChildContent("sequence|null","");
    xml.UpdateChildContent("octets",md5_base64);

    CkAsn asn = new CkAsn();
    asn.LoadAsnXml(xml.getXml());
    Log.i(TAG, "ASN.1 = " + asn.getEncodedDer("base64"));

    // Sign with the private key.
    CkRsa rsa = new CkRsa();
    success = rsa.ImportPrivateKeyObj(privKey);
    if (success == false) {
        Log.i(TAG, rsa.lastErrorText());
        return;
        }

    // Create the opaque signature.
    CkBinData bdSig = new CkBinData();
    bdSig.AppendEncoded(asn.getEncodedDer("base64"),"base64");
    success = rsa.OpenSslSignBd(bdSig);
    if (success == false) {
        Log.i(TAG, rsa.lastErrorText());
        return;
        }

    // bd now contains the opaque signature, which embeds the ASN.1, which contains the MD5 hash.
    // We're going to add this line:
    // 800|4199800|1|BASE64_SIGNATURE|CERT_SERIAL_NUM|

    CkCert cert = new CkCert();
    success = cert.LoadFromFile("qa_data/certs/mexico_test/Certificados_de_Prueba/Certificados_Pruebas/Personas Morales/EKU9003173C9_20230517223532/CSD_EKU9003173C9_20230517223903/CSD_Sucursal_1_EKU9003173C9_20230517_223850.cer");
    if (success == false) {
        Log.i(TAG, cert.lastErrorText());
        return;
        }

    String serialHex = cert.serialNumber();
    // The serial in hex form looks like this:   3330303031303030303030353030303033343136
    // Decode to us-ascii.
    CkStringBuilder sbSerial = new CkStringBuilder();
    sbSerial.DecodeAndAppend(serialHex,"hex","us-ascii");
    Log.i(TAG, "serial number in us-ascii: " + sbSerial.getAsString());

    int numReplaced = sb.Replace("CERT_SERIAL",sbSerial.getAsString());
    numReplaced = sb.Replace("BASE64_SIGNATURE",bdSig.getEncoded("base64"));

    Log.i(TAG, "------------------------------------");
    Log.i(TAG, "Result:");
    Log.i(TAG, sb.getAsString());

  }

  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."
  }
}