src/org/average/nfcauthcr/YkNeo.java

   1 package org.average.nfcauthcr;
   2
   3 import java.io.IOException;
   4 import java.util.Arrays;
   5
   6 import android.nfc.NfcAdapter;
   7 import android.nfc.Tag;
   8 import android.nfc.TagLostException;
   9 import android.nfc.tech.IsoDep;
  10 //import android.util.Log;
  11
  12 public class YkNeo {
  13
  14         // This is a CCID APDU, ISO 7816-4.
  15         // 00 A4 04 00 xx AID - GlobalPlatform - SELECT
  16         // Lc, send data = 07: A0 00 00 05 27 20 01
  17         // Le, recv data = 00
  18         private static final byte[] selectApdu =
  19                 {0x00, (byte) 0xA4, 0x04, 0x00, 0x07, (byte) 0xA0,
  20                  0x00, 0x00, 0x05, 0x27, 0x20, 0x01, 0x00};
  21
  22         private static final byte SLOT_CHAL_HMAC1 = 0x30;
  23         private static final byte SLOT_CHAL_HMAC2 = 0x38;
  24
  25         public static final byte[] doChallengeYubiKey(IsoDep isoTag, int slot,
  26                                                 byte[] challenge) {
  27                 try {
  28                         isoTag.connect();
  29                         byte[] resp = isoTag.transceive(selectApdu);
  30                         int length = resp.length;
  31                         //Log.v(TAG, "response to select length is " + length);
  32                         if (resp[length - 2] != (byte)0x90 ||
  33                             resp[length - 1] != 0x00) {
  34                                 //Log.v(TAG, "Wrong response to select");
  35                                 //Toast.makeText(this, R.string.tag_error,
  36                                 //              Toast.LENGTH_LONG).show();
  37                                 return null;
  38                         }
  39                         byte[] crApdu = new byte[69];
  40                         crApdu[0] = 0x00; // CLA
  41                         crApdu[1] = 0x01; // INS
  42                         switch (slot) {
  43                         case 1: crApdu[2] = SLOT_CHAL_HMAC1; break; // P1
  44                         case 2: crApdu[2] = SLOT_CHAL_HMAC2; break; // P1
  45                         }
  46                         crApdu[3] = 0x00; // P2
  47                         crApdu[4] = 63;   // Lc
  48                         System.arraycopy(challenge, 0, crApdu, 5,
  49                                                 challenge.length); // Payload
  50                         crApdu[crApdu.length-1] = 22; // Le
  51                         resp = isoTag.transceive(crApdu);
  52                         length = resp.length;
  53                         if (resp[length - 2] != (byte)0x90 ||
  54                             resp[length - 1] != 0x00) {
  55                                 //Log.v(TAG, "Wrong response to challenge");
  56                                 //Toast.makeText(this, R.string.tag_error,
  57                                 //              Toast.LENGTH_LONG).show();
  58                                 return null;
  59                         }
  60                         //Log.v(TAG, "response to challenge length is " + length);
  61                         return Arrays.copyOf(resp, length-2);
  62                 } catch (TagLostException e) {
  63                         //Log.v(TAG, e.getMessage());
  64                         //Toast.makeText(this,
  65                         //      R.string.tag_lost, Toast.LENGTH_LONG).show();
  66                 } catch (IOException e) {
  67                         //Log.v(TAG, e.getMessage());
  68                         //Toast.makeText(this,
  69                         //      getText(R.string.tag_error) +
  70                         //      e.getMessage(),
  71                         //      Toast.LENGTH_LONG).show();
  72                 }
  73                 return null;
  74         }
  75 }