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androidweb-serviceshashksoap2sha

Compare two hash strings generated using SHA-1 in Android


Here is the flow of my Android code:

I am using SHA-1 hashing to hash a password entered by the user via EditText. I get a hash string as output over here.

After that I am calling a SOAP web service (created using .NET framework) that performs the same SHA-1 hashing using ASCII encoding and returns me another hash string.

Now since the input string is same in both the cases, my hash strings are same as expected. See logcat below. But when I am comparing the hash strings, I am not getting the result as expected

Here is my Android code followed by logcat:

           package com.kar.encodePassword;
           import java.io.IOException;
           import java.io.UnsupportedEncodingException;
           import java.net.SocketException;
           import java.security.MessageDigest;
           import java.security.NoSuchAlgorithmException;
           import org.ksoap2.SoapEnvelope;
           import org.ksoap2.serialization.SoapObject;
           import org.ksoap2.serialization.SoapPrimitive;
           import org.ksoap2.serialization.SoapSerializationEnvelope;
           import org.ksoap2.transport.HttpTransportSE;
           import org.xmlpull.v1.XmlPullParserException;
           import android.app.Activity;
           import android.os.Bundle;
           import android.util.Base64;
           import android.util.Log;
           import android.view.View;
           import android.widget.Button;
           import android.widget.EditText;
           import android.widget.Toast;

   public class PaswordencodingActivity extends Activity {
       /** Called when the activity is first created. */

 private static final String soap_action = "http://tempuri.org/HashCode";
 private static final String method_name = "HashCode";
 private static final String namespace2 = "http://tempuri.org/";
 private static final String url2 = "http://10.0.2.2/checkhash/Service1.asmx"; 

String password="abc";
public final static int NO_OPTIONS = 0;
String hash;
    String result2;


@Override
public void onCreate(Bundle savedInstanceState) 
{
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);

    final EditText pass=(EditText)findViewById(R.id.editText1);
    Button encode=(Button)findViewById(R.id.button1);            
    encode.setOnClickListener(new View.OnClickListener() {
        public void onClick(View v)  {
            // Perform action on click
            password=pass.getText().toString();
            if(password!=null){
                try { 
        SHA1(password) ;
        } catch (UnsupportedEncodingException e) {                                          
                      e.printStackTrace();
        } catch (IOException e) {   
            e.printStackTrace();                    
                      }
            }
            else{
       Toast.makeText(PaswordencodingActivity.this, "this is a negative onClick", Toast.LENGTH_LONG).show();
            }

           }

          });


        }


private static String convertToHex(byte[] data) throws java.io.IOException 
 {
        System.out.println("data received is"  +data);

        StringBuffer sb = new StringBuffer();
        String hex=null;

        hex=Base64.encodeToString(data, 0, data.length, NO_OPTIONS);

        for (int i = 0; i < data.length; i++) 
        {            
            if (hex.length() == 1) 
            {
                sb.append('0');
            }
            sb.append(hex);
        }

       return sb.toString();
    }

public void SHA1(String text) throws IOException
{
    MessageDigest mdSha1 = null;
    try 
    {
      mdSha1 = MessageDigest.getInstance("SHA-1");
    } catch (NoSuchAlgorithmException e1) {
      Log.e("myapp", "Error initializing SHA1 message digest");
    }
    mdSha1.update(text.getBytes("iso-8859-1"), 0, text.length());
    byte[] data = mdSha1.digest();
    hash=convertToHex(data);

    System.out.println("data going is"  +data);
    System.out.println("hash value"+hash);

    try
    {
        result2=call3(password);
        if(result2.equalsIgnoreCase(hash.toString()))
        System.out.println("success");


    } catch (XmlPullParserException e)
    {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }   

        }

public String call3(String pass) throws XmlPullParserException
{
        String b=""; 

        SoapObject request = new SoapObject(namespace2, method_name);      
        request.addProperty("str",pass);

        SoapSerializationEnvelope envelope = new SoapSerializationEnvelope(SoapEnvelope.VER11); 
        envelope.dotNet = true; 
        envelope.setOutputSoapObject(request);

        HttpTransportSE  android = new HttpTransportSE(url2);

        android.debug = true; 
 try 
 {

        android.call(soap_action, envelope);

        SoapPrimitive result = (SoapPrimitive)envelope.getResponse();
        Log.i("myapp",result.toString());
        System.out.println(" --- response ---- " + result); 
        b=result.toString();


        } catch (SocketException ex) { 
            ex.printStackTrace(); 
        } catch (Exception e) { 
            e.printStackTrace(); 
        } 

        return b;   

}
}

Basically when I am trying to compare the two hash strings I am not getting the result

Why so ? can anyone help?

Logcat:

        11-25 17:09:50.899: INFO/System.out(275): data received is[B@44ef8eb0
        11-25 17:09:50.909: INFO/System.out(275): data going is[B@44ef8eb0
        11-25 17:09:50.909: INFO/System.out(275): hash valueUGGpBypVug3K+/4xONpqv9wkFd8=
        11-25 17:09:50.909: INFO/System.out(275): UGGpBypVug3K+/4xONpqv9wkFd8=
        11-25 17:09:50.909: INFO/System.out(275): UGGpBypVug3K+/4xONpqv9wkFd8=
        11-25 17:09:50.909: INFO/System.out(275): UGGpBypVug3K+/4xONpqv9wkFd8=
        11-25 17:09:50.909: INFO/System.out(275): UGGpBypVug3K+/4xONpqv9wkFd8=
        11-25 17:09:50.909: INFO/System.out(275): UGGpBypVug3K+/4xONpqv9wkFd8=
        11-25 17:09:50.909: INFO/System.out(275): UGGpBypVug3K+/4xONpqv9wkFd8=
        11-25 17:09:50.909: INFO/System.out(275): UGGpBypVug3K+/4xONpqv9wkFd8=
        11-25 17:10:01.730: INFO/myapp(275): UGGpBypVug3K+/4xONpqv9wkFd8=
        11-25 17:10:01.730: INFO/System.out(275):  --- response ---- UGGpBypVug3K+/4xONpqv9wkFd8=

Solution

  • Try

    result2 = result2.trim();
    hash = hash.trim();
    
    System.out.println("result2='" + result2 + "'");
    System.out.println("hash ='" + hash + "'");
    
    if(result2.equalsIgnoreCase(hash))
       System.out.println("success");
    

    If this does not help, check the actual arrays:

    byte[] a = result.toString().getBytes() 
    byte[] b = hash..getBytes();
    

    If the arrays are not equal, you have strings in different encodings.