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APDU Command

JavaCard Applet Development Related Questions and Answers.
Posts: 3
Joined: Tue Dec 13, 2016 8:45 pm
Points :72

APDU Command

Post by keiji » Tue Dec 13, 2016 8:53 pm

I got this code from the internet and I want to play around with it. But I dont know how to send command to APDU?
Your help is greatly appreciated.

Code: Select all

package Eighth;

import javacard.framework.*;
import javacardx.crypto.*;

public class ECDSA extends Applet
    private byte[] plaintext ;
    private ECPrivateKey            objECDSAPriKey=null;    // Object for ECDSA Private Key
    private ECPublicKey             key=null;               // Object for ECDSA Public Key
    private KeyPair                 objECDSAKeyPair=null;   // Object for ECDSA Key Pair
    private Signature               objECDSASign=null;

    final static short  BAS  =  0;

    private final static byte[] fp = new byte[] {
        (byte)0xFF, (byte)0xFF, (byte)0xFF, (byte)0xFF, (byte)0xFF, (byte)0xFF, (byte)0xFF,
        (byte)0xFF, (byte)0xFF, (byte)0xFF, (byte)0xFF, (byte)0xFF, (byte)0xFF, (byte)0xFF,
        (byte)0xFF, (byte)0xFE, (byte)0xFF, (byte)0xFF, (byte)0xFF, (byte)0xFF, (byte)0xFF,
        (byte)0xFF, (byte)0xFF, (byte)0xFF };
    private final static byte[] r = new byte[] {
        (byte)0xFF, (byte)0xFF, (byte)0xFF, (byte)0xFF, (byte)0xFF, (byte)0xFF, (byte)0xFF,
        (byte)0xFF, (byte)0xFF, (byte)0xFF, (byte)0xFF, (byte)0xFF, (byte)0x99, (byte)0xDE,
        (byte)0xF8, (byte)0x36, (byte)0x14, (byte)0x6B, (byte)0xC9, (byte)0xB1, (byte)0xB4,
        (byte)0xD2, (byte)0x28, (byte)0x31 };
    private final static byte[] a = new byte[] {
        (byte)0xFF, (byte)0xFF, (byte)0xFF, (byte)0xFF, (byte)0xFF, (byte)0xFF, (byte)0xFF,
        (byte)0xFF, (byte)0xFF, (byte)0xFF, (byte)0xFF, (byte)0xFF, (byte)0xFF, (byte)0xFF,
        (byte)0xFF, (byte)0xFE, (byte)0xFF, (byte)0xFF, (byte)0xFF, (byte)0xFF, (byte)0xFF,
        (byte)0xFF, (byte)0xFF, (byte)0xFC };
    private final static byte[] b = new byte[] {
        (byte)0x64, (byte)0x21, (byte)0x05, (byte)0x19, (byte)0xE5, (byte)0x9C, (byte)0x80,
        (byte)0xE7, (byte)0x0F, (byte)0xA7, (byte)0xE9, (byte)0xAB, (byte)0x72, (byte)0x24,
        (byte)0x30, (byte)0x49, (byte)0xFE, (byte)0xB8, (byte)0xDE, (byte)0xEC, (byte)0xC1,
        (byte)0x46, (byte)0xB9, (byte)0xB1 };
    private final static byte[] g = new byte[] {
        (byte)0x04, (byte)0x18, (byte)0x8D, (byte)0xA8, (byte)0x0E, (byte)0xB0, (byte)0x30,
        (byte)0x90, (byte)0xF6, (byte)0x7C, (byte)0xBF, (byte)0x20, (byte)0xEB, (byte)0x43,
        (byte)0xA1, (byte)0x88, (byte)0x00, (byte)0xF4, (byte)0xFF, (byte)0x0A, (byte)0xFD,
        (byte)0x82, (byte)0xFF, (byte)0x10, (byte)0x12, (byte)0x07, (byte)0x19, (byte)0x2B,
        (byte)0x95, (byte)0xFF, (byte)0xC8, (byte)0xDA, (byte)0x78, (byte)0x63, (byte)0x10,
        (byte)0x11, (byte)0xED, (byte)0x6B, (byte)0x24, (byte)0xCD, (byte)0xD5, (byte)0x73,
        (byte)0xF9, (byte)0x77, (byte)0xA1, (byte)0x1E, (byte)0x79, (byte)0x48, (byte)0x11 }; //49
     private final static short k = 1;   

    public static void install(byte[] bArray, short bOffset, byte bLength){
    new ECDSA(bArray, bOffset, bLength);

    private ECDSA(byte bArray[], short bOffset, byte bLength){   

    plaintext       = new byte[0x100] ;         

    Util.arrayFillNonAtomic(plaintext,  BAS, (short)0x100, (byte)0);


    public void process(APDU apdu){
    byte buf[] = apdu.getBuffer();

        case (byte)0xA4:

        case (byte)0x46:


      objECDSAPriKey = (ECPrivateKey)KeyBuilder.buildKey(KeyBuilder.TYPE_EC_FP_PRIVATE, KeyBuilder.LENGTH_EC_FP_192, false);
      key = (ECPublicKey)KeyBuilder.buildKey(KeyBuilder.TYPE_EC_FP_PUBLIC,  KeyBuilder.LENGTH_EC_FP_192, false);

        key.setFieldFP(fp, (short)0, (short)fp.length);
        key.setR(r, (short)0, (short)r.length);
        key.setA(a, (short)0, (short)a.length);
        key.setB(b, (short)0, (short)b.length);
        key.setG(g, (short)0, (short)g.length);

     objECDSAKeyPair = new KeyPair(KeyPair.ALG_EC_FP, KeyBuilder.LENGTH_EC_FP_192);

     catch(CryptoException c)
        short reason = c.getReason();   

     // On-Card Key Generation Process

     // Obtain Key References
      objECDSAPriKey = (ECPrivateKey)objECDSAKeyPair.getPrivate();
      key = (ECPublicKey)objECDSAKeyPair.getPublic(); 

     // Create Signature Object
      objECDSASign = Signature.getInstance(Signature.ALG_ECDSA_SHA, false);


       case (byte)0x2E:                       
            short   Le = apdu.setOutgoing();   
            short   sSignLen=0 ;

            // Init with Private Key
            objECDSASign.init(objECDSAPriKey, Signature.MODE_SIGN);

            // Sign Data
            sSignLen = objECDSASign.sign(plaintext, BAS, Le, buf, BAS);

            apdu.sendBytes(BAS, sSignLen);



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Posts: 630
Joined: Thu May 21, 2015 4:05 am
Points :3035

Re: APDU Command

Post by UNKNwYSHSA » Tue Dec 13, 2016 9:49 pm

Send APDU to the Applet?

You can use JCIDE/JCOP development kit for debug;
And if you have one javacard, load applet, send APDUs with APDU tools, like pyApdutool, GPShell ...
sense and simplicity

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