Android™

Demonstrates the MacBytes Method

Demonstrates the MacBytes method to do HMAC-SHA256, HMAC-SHA1, and HMAC-MD5. 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);

    //  This example assumes Chilkat Crypt2 to have been previously unlocked.
    //  See Unlock Crypt2 for sample code.

    //  Demonstrates how to reproduce the following results found at
    //  https://en.wikipedia.org/wiki/Hash-based_message_authentication_code

    //  HMAC_SHA256("key", "The quick brown fox jumps over the lazy dog") = 0xf7bc83f430538424b13298e6aa6fb143ef4d59a14946175997479dbc2d1a3cd8
    //  HMAC_MD5("key", "The quick brown fox jumps over the lazy dog")    = 0x80070713463e7749b90c2dc24911e275
    //  HMAC_SHA1("key", "The quick brown fox jumps over the lazy dog")   = 0xde7c9b85b8b78aa6bc8a7a36f70a90701c9db4d9

    CkCrypt2 crypt = new CkCrypt2();

    crypt.put_MacAlgorithm("hmac");
    crypt.put_EncodingMode("hex");
    crypt.SetMacKeyString("key");
    String sData = "The quick brown fox jumps over the lazy dog";

    //  We're doing this in a convoluted, roundabout fashion to show syntax
    //  and data types for handling binary data.
    //  The straightforward way of doing an HMAC on a string is
    //  shown here: HMAC String
    CkByteData dataToHmac = new CkByteData();
    CkBinData binData = new CkBinData();
    binData.AppendString(sData,"utf-8");
    success = binData.GetBinary(dataToHmac);

    CkByteData macBytes = new CkByteData();

    crypt.put_HashAlgorithm("SHA-256");
    success = crypt.MacBytes(dataToHmac,macBytes);
    binData.Clear();
    binData.AppendBinary(macBytes);
    Log.i(TAG, "HMAC_SHA256: " + binData.getEncoded("hex"));

    crypt.put_HashAlgorithm("MD5");
    success = crypt.MacBytes(dataToHmac,macBytes);
    binData.Clear();
    binData.AppendBinary(macBytes);
    Log.i(TAG, "HMAC_MD5: " + binData.getEncoded("hex"));

    crypt.put_HashAlgorithm("SHA-1");
    success = crypt.MacBytes(dataToHmac,macBytes);
    binData.Clear();
    binData.AppendBinary(macBytes);
    Log.i(TAG, "HMAC_SHA1: " + binData.getEncoded("hex"));

    //  The output is the same (ignore case)
    //  HMAC_SHA256: F7BC83F430538424B13298E6AA6FB143EF4D59A14946175997479DBC2D1A3CD8
    //  HMAC_MD5: 80070713463E7749B90C2DC24911E275
    //  HMAC_SHA1: DE7C9B85B8B78AA6BC8A7A36F70A90701C9DB4D9

  }

  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."
  }
}