NTAG 21x Authentication about nfc-pcsc HOT 6 OPEN

reader.on('card', async card => {

  console.log('card detected', card);

  // PASSWORD (4 bytes) (stored on card in page 18)
  const password = Buffer.from([
    0xff,
    0xff,
    0xff,
    0xff,
  ]);

  // PACK (2 bytes) (stored in page 19 as first two bytes)
  // PACK is the response from card in case of successful PWD_AUTH cmd
  const pack = Buffer.from([
    0xab,
    0xcd
  ]);

  try {

    // CMD: PWD_AUTH via Direct Transmit (ACR122U) and Data Exchange (PN533)
    const cmd = Buffer.from([
      0xFF, // Class
      0x00, // Direct Transmit (see ACR122U)
      0x00, // ...
      0x00, // ...
      0x07, // Length of Direct Transmit payload
      // Payload (7 bytes)
      0xd4, // Data Exchange Command (see PN533 docs)
      0x42, // inserted
      0x1b, // PWD_AUTH
      ...password,
    ]);

    console.log('pwd_auth cmd', cmd);

    const response = await reader.transmit(cmd, 7);

    console.log('pwd_auth response', response);
    // pwd_auth response should look like the following (7 bytes)
    // d5 43 00 ab cd 90 00
    // byte 0: d5 prefix for response of Data Exchange Command (see PN533 docs)
    // byte 1: 43 prefix for response of Data Exchange Command (see PN533 docs)
    // byte 2: Data Exchange Command Status 0x00 is success (see PN533 docs)
    // bytes 3-4: Data Exchange Command Response – our PACK (set on card in page 19, in bytes 0-1) from card
    // bytes 5-6: ACR122U success code


  } catch (err) {
    console.error('pwd_auth error', err);
    return;
  }

});

reader.on('card', async card => {

  try {

    // set custom PASSWORD (4 bytes) (stored in page 18)
    await reader.write(19, password);

    // set custom PACK (2 bytes) (stored in page 19 as first two bytes)
    const packPage = await reader.read(19, 4);
    packPage[0] = pack[0];
    packPage[1] = pack[1];
    await reader.write(19, packPage);

    // read current configuration
    const config = await reader.read(16, 8);

    // Configuration page 16
    console.log(config[0]);
    console.log(config[1]);
    console.log(config[2]);
    console.log(config[3]); // AUTH0 (default: 0xff)

    // Configuration page 17
    console.log(config[4]); // ACCESS
    console.log(config[5]); // VCTID (default: 0x05)
    console.log(config[6]);
    console.log(config[7]);

    // Protect everything (start with first data page)
    config[3] = 0x04;

    // set ACCESS bits
    // bit 7: PROT One bit inside the ACCESS byte defining the memory protection
    //          0b ... write access is protected by the password verification
    //          1b ... read and write access is protected by the password verification
    // bit 6: CFGLCK Write locking bit for the user configuration
    //        - 0b ... user configuration open to write access
    //        - 1b ... user configuration permanently locked against write access
    // bits 5-3: reserved
    // bits 2-0: AUTHLIM
    // bit number-76543210
    //            ||||||||
    config[4] = 0b10000000;

    // set custom access rules
    await reader.write(16, config);

  } catch (err) {
    console.error(err);
  }

});

try {

	// set custom PASSWORD (4 bytes) (stored in page 229)
	await reader.write(229, password);

	// set custom PACK (2 bytes) (stored in page 230 as first two bytes)
	const packPage = await reader.read(230, 4);
	packPage[0] = pack[0];
	packPage[1] = pack[1];
	await reader.write(230, packPage);

	// read current configuration
	const config = await reader.read(227, 8);

	// Configuration page 16
	console.log(config[0]);
	console.log(config[1]);
	console.log(config[2]);
	console.log(config[3]); // AUTH0 (default: 0xff)

	// Configuration page 17
	console.log(config[4]); // ACCESS
	console.log(config[5]); // VCTID (default: 0x05)
	console.log(config[6]);
	console.log(config[7]);

	// Protect everything (start with first data page)
	config[3] = 0x04;

	// set ACCESS bits
	// bit 7: PROT One bit inside the ACCESS byte defining the memory protection
	//          0b ... write access is protected by the password verification
	//          1b ... read and write access is protected by the password verification
	// bit 6: CFGLCK Write locking bit for the user configuration
	//        - 0b ... user configuration open to write access
	//        - 1b ... user configuration permanently locked against write access
	// bits 5-3: reserved
	// bits 2-0: AUTHLIM
	// bit number-76543210
	//            ||||||||
	config[4] = 0b10000000;

	// set custom access rules
	await reader.write(227, config);

} catch (err) {
	console.error(err);
}