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Android™

RSA Signature SHA256withRSA, iso-8859-1, base64

See more RSA Examples

RSA sign the iso-8859-1 byte representation of a string with SHA256withRSA, and return the signature in the base64 encoding.

Chilkat Android™ Downloads

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.

    // This example will duplicate the following Java code:
    // 
    // Signature sign = Signature.getInstance("SHA256withRSA");
    // sign.initSign(privateKey);
    // sign.update(original.getBytes(Charset.forName("ISO-8859-1")));
    // 
    // ...
    // byte[] resultado = sign.sign();
    // sello = encodeByteArrayToBase64(resultado);
    // 

    // Load an RSA private key for signing.
    // You can load any format file.  This example loads a .pem, but you can provide path to any type of file holding a private key.
    CkPrivateKey privKey = new CkPrivateKey();
    success = privKey.LoadAnyFormatFile("qa_data/pem/rsa_passwd.pem","passwd");
    if (success == false) {
        Log.i(TAG, privKey.lastErrorText());
        return;
        }

    CkRsa rsa = new CkRsa();
    rsa.UsePrivateKey(privKey);

    String originalData = "This is the string to be hashed an RSA signed.";

    // Indicate that we want the iso-8859-1 byte representation of the string to be signed
    rsa.put_Charset("iso-8859-1");

    // We want the RSA signature in base64 format
    rsa.put_EncodingMode("base64");

    String sigBase64 = rsa.signStringENC(originalData,"sha256");
    Log.i(TAG, sigBase64);

  }

  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."
  }
}