MFStandardException: Write Failed

[dahmoun_miriam]

Hi,
I implemented a signed midlet to write data into internal mifare card of Nokia 6212. First, I tested this midlet under two Nokia 6212 and it works fine; data is wrote into the mifare card.
But, when I had tried it under a third Nokia 6212, I get connected to the Mifare internal card but write operation failed and I reached this exception :
MFStandardException: Write Failed

Any Idea please ?

Cheers
Miriam

[Pybel]

The internal Mifare card of this 6212 might be protected. Do you write the data with a MFStandardConnection, accessing the MAD and creating/opening your own application or do you use the regular NDEF Connection?

If you're not familiar with Mifare 4k, I suggest you take a look at the specifications : http://www.nxp.com/acrobat_download/...on/m043531.pdf especially the part about the tag's structure and read/write protection.

[dahmoun_miriam]

Thank you a lot for replaying 

I use a MFStandardConnection like showing in this part of my code:

try {

            // get URI of the secure element from the system
            uri = System.getProperty("internal.mf.url");

            // Opening the Conneciton to the Secure Element
            conn = (MFStandardConnection) Connector.open(uri);
            
            
            if (conn != null){
            	info.setText("Connection OK");
            	sector = conn.getSector(14);
            	
            	// To initialize Blocks
            	MFBlock bloque_0 = sector.getBlock(0);
    			bloque_0.write(null, zeroBuffer, 0, 16, 0);
    			MFBlock bloque_01 = sector.getBlock(1);
    			bloque_01.write(null, zeroBuffer, 0, 16, 0);
    			
            }
       
        } catch (IOException ie) {
            info.setText("Could not Select: " + ie.toString());
        } catch (SecurityException se) {
            info.setText("Error, Application not trusted (sign MIDLet!): " + se.toString());
        }catch (Exception e){
			 info.setText("Exception: " + e.toString());
				
        }

I insist in the fact that the same midlet is correctly executed into two Nokia 6212.

Cheers
Miriam

[Pybel]

Thank you a lot for replaying 

           	sector = conn.getSector(14);
            	
            	// To initialize Blocks
            	MFBlock bloque_0 = sector.getBlock(0);
    			bloque_0.write(null, zeroBuffer, 0, 16, 0);
    			MFBlock bloque_01 = sector.getBlock(1);
    			bloque_01.write(null, zeroBuffer, 0, 16, 0);
    			
            }

It looks like you're trying to write in sector 14 with the default key. If it works on 2 phones but not on a third, this probably means that the sector 14 is locked on the 3rd phone (According to the SDK documentation the MFBlock.write() method throws a MFStandardException if authentication fails).
There's probably some data already in there and the trailer of this sector has been changed so you can't write with the default key.

It might be better for you to use the Mifare Application Directory. This way, rather than writing to a specific sector, you'll let the card manage the sectors and won't have that kind of problem (as long as you've got the key to access the MAD and enough free sectors left on the card).

[dahmoun_miriam]

Hi Pybel,
Thank you again for replaying, your suggestions are very interesting .
But, the problem is that project specifications require writing into Sector 14. So I have to found the Key to access to this sector, case it is access protected.

Cheers
Miriam.

[dahmoun_miriam]

Hi,
Since I can’t find key to access to Sector 14, I write an applet to access to Mifare Card using jetZ library for Mifare Access (proposed by JCOP plugin).
But Uploading applet failed, since to access to Nokia 6212 Mifare card, you must use Giesecke & Devrient’s (G&D) specific libraries (ExtSystem) provided by Sm@rtCafé®
Professional Toolkit

Cheers
Miriam.