2082672_zh-CN

[#1]

如何在 NTAG424 DNA 中启用 CMAC、UID、COUNTER 和 RAND？

我试图使用最新的 Android SDK 库来设置基于 AES 密钥的动态 URL，但我无法做到。

nxpnfcandroidlib-release-protected.aar

这是我的代码

override fun onNewIntent(intent: Intent) {
	Log.i("NFC", "Intent action: ${intent.action}")
	super.onNewIntent(intent)

	Log.i("MainActivity", "NFC tag discovered")

	val cardType = libInstance.getCardType(intent)
	Log.i("MainActivity", "Detected card type: $cardType")
	if (cardType == CardType.NTAG424DNA) {
	    val ntag424DNA: INTAG424DNA = DESFireFactory.getInstance().getNTAG424DNA(libInstance.customModules)
	    val reader: IReader = ntag424DNA.reader

	    try {

	        if (!reader.isConnected) {
	            reader.connect()
	        }

	        ntag424DNA.isoSelectApplicationByDFName(NTAG424DNA_APP_NAME)
	        Log.i("NFC", "ISO selected app by DF Name ")

	        authenticateTag(ntag424DNA, KEY_AES128_DEFAULT)
		    creatingNDEFmessage(ntag424DNA)
            authenticateTag(ntag424DNA, KEY_AES128_DEFAULT)
		    changeFileSettings(ntag424DNA, 0x01)

            authenticateTag(ntag424DNA, KEY_AES128_DEFAULT)
	        ntag424DNA.setPICCConfiguration(true)
	        Log.i("MainActivity", " PICC Configuration updated to enable SDM globally.")

	        authenticateTag(ntag424DNA, KEY_AES128_DEFAULT)
	        changeSDMFileSettings(ntag424DNA, 0x01)

	        if (reader.isConnected) {
	            reader.close()
	        }
	    } catch (e: Exception) {
	        e.printStackTrace()
	    }

	}
}

private fun creatingNDEFmessage(ntag424DNA: INTAG424DNA) {
    // 1. Creating URI NDEF message
    val msg = NdefMessageWrapper(
        NdefRecordWrapper(
            NdefRecordWrapper.TNF_ABSOLUTE_URI,
            "https://domain.com?uid=04BB38D2AA1191&ctr=0001&cmac=3ab665b76b795cb9bf76a17956cc9fb3&rand=422def08-8a1c-49c9-9138-434cde858faa".toByteArray(
                Charset.forName("US-ASCII")
            ), ByteArray(0), ByteArray(0)
        )
    )

    ntag424DNA.writeNDEF(msg);
    Log.i("MainActivity", "URI NDEF message written successful ")

    val ndefRead = ntag424DNA.readNDEF()
    Log.i("MainActivity", "Read URI NDEF message ${CustomModules.getUtility().dumpBytes(ndefRead.toByteArray())}")

}

private fun changeFileSettings(ntag424DNA: INTAG424DNA, fileNumber: Int) {
    // 3. Create NTAG 424 DNA file settings for E104
    val fileSettings = NTAG424DNAFileSettings(
        MFPCard.CommunicationMode.Encrypted,    // = 0x03 = Full ENC + CMAC (SUN)
        0x0E.toByte(),             // Read access = key slot 0x00 maybe 0x01
        0x0E.toByte(),             // Write access = always
        0x0E.toByte(),             // RW access = always
        0x0E.toByte()              // Change access = always
    )

    Log.i("MainActivity", "Prepare for saving changes in file $fileNumber")
    ntag424DNA.changeFileSettings(fileNumber, fileSettings)
    Log.i("NFC", " File settings updated $fileNumber")
}


private fun changeSDMFileSettings(ntag424DNA: INTAG424DNA, fileNumber: Int) {
    val fileSettings = ntag424DNA.getFileSettings(fileNumber);

    fileSettings.isSDMEnabled = true;
    fileSettings.isUIDMirroringEnabled = true;

    fileSettings.piccDataOffset = intTo2ByteArray(51)
    fileSettings.sdmMacOffset = intTo2ByteArray(51)
    fileSettings.sdmMacInputOffset = intTo2ByteArray(51)
    fileSettings.sdmReadCounterOffset = intTo2ByteArray(51)
    fileSettings.uidOffset = intTo2ByteArray(51)
    fileSettings.sdmAccessRights = byteArrayOf(0x00, 0x00)

    Log.i("MainActivity", "Prepare for saving SDM changes in file $fileNumber")
    ntag424DNA.changeFileSettings(fileNumber, fileSettings)
    Log.i("NFC", " File settings updated: SUN CMAC enabled on $fileNumber")
}

private fun intTo2ByteArray(value: Int): ByteArray {
    return byteArrayOf(
        ((value shr  and 0xFF).toByte(),
        (value and 0xFF).toByte()
    )
}

我知道偏移量与 URL 中的位置不匹配，但无论我做了什么更改，都还是会出现这个错误。看起来，由于某些原因，这些设置无法通过这种方法保存。

ntag424DNA.changeFileSettings(fileNumber, fileSettings)

错误信息如下

com.nxp.nfclib.exceptions.UsageException: Invalid Parameters! {Invalid Value for PICC Offset}

代码示例Re: How can i enable CMAC, UID, COUNTER and RAND in NTAG424 DNA?

问题是由于错误的偏移值造成的。看来 ntag 保留了 21 个默认索引。现在，我们正试图更改 128 aes 密钥，但 changekey() 函数不起作用。

@UKCAS

Re: How can i enable CMAC, UID, COUNTER and RAND in NTAG424 DNA?

嘿，

我正在关注这个话题来安装 JSON 数据，但它对我不起作用。这是我第一次与硬件打交道，因此工作更具挑战性。我使用的是恩智浦 Android 库和这里的示例 Android 应用程序： https://www.nxp.com/design/design-center/software/rfid-developer-resources/taplinx-software-develo...

以下是我在 Sample_Application_Android/src/main/java/com/nxp/sampletaplinx/WriteActivity.java 中的代码

public static byte[] intTo2ByteArray(int value) {
    return new byte[] {
            (byte) (value & 0xFF),        // LSB
            (byte) ((value >> 8) & 0xFF), // middle byte
            (byte) ((value >> 16) & 0xFF) // MSB
    };
}

private void tag424DNACardLogic(INTAG424DNA ntag424DNA) {
    byte[] KEY_AES128_DEFAULT = new byte[] {
            (byte)0x00, (byte)0x00, (byte)0x00, (byte)0x00,
            (byte)0x00, (byte)0x00, (byte)0x00, (byte)0x00,
            (byte)0x00, (byte)0x00, (byte)0x00, (byte)0x00,
            (byte)0x00, (byte)0x00, (byte)0x00, (byte)0x00,
    };
    byte[] NTAG424DNA_APP_NAME =
            {(byte) 0xD2, (byte) 0x76, 0x00, 0x00, (byte) 0x85, 0x01, 0x01};
    byte[] data ={ 0x73, 0x75, 0x73, 0x68, 0x69, 0x6C };

    mStringBuilder.append("\n\n");
    int timeOut = 2000;
    try {
        ntag424DNA.isoSelectApplicationByDFName(NTAG424DNA_APP_NAME);
        KeyData aesKeyData = new KeyData();
        Key keyDefault = new SecretKeySpec(KEY_AES128_DEFAULT, "AES");
        aesKeyData.setKey(keyDefault);
       ntag424DNA.authenticateEV2First(0, aesKeyData, null);

        mStringBuilder.append(getString(R.string.Authentication_status_true));
        mStringBuilder.append("\n\n");

        ntag424DNA.setPICCConfiguration(true);

        String jsonTemplate = "{\"uuid\":\"00000000000000\",\"counter\":\"000000\",\"cmac\":\"0000000000000000\",\"domain1\":" + 1 + ",\"domain2\":" + 1 + "}";
        byte[] jsonBytes = jsonTemplate.getBytes("UTF-8");

        NTAG424DNAFileSettings fs = new NTAG424DNAFileSettings(
                CommunicationMode.Plain,  // or MAC/ENC depending on your security
                (byte) 0x0E, // Read access: Key 0
                (byte) 0x0E, // Write access: Key 0
                (byte) 0x0E, // Read/Write: Key 0
                (byte) 0x00  // Change access: Free
        );

        byte[] type = "U".getBytes("US-ASCII");
        fs.setSDMEnabled(true);
        fs.setUIDMirroringEnabled(true);
        fs.setSDMReadCounterEnabled(true);

        byte[] bytes = new byte[] { (byte)0xE0, (byte)0x00, (byte)0x00 };
        fs.setSdmAccessRights(bytes);

        byte[] uuidOffset = intTo2ByteArray(8);

        fs.setUidOffset(uuidOffset);

        byte[] readCounterOffset = intTo2ByteArray(35);
        fs.setSdmReadCounterOffset(readCounterOffset);

        byte[] macOffset = intTo2ByteArray(51);

        fs.setSdmMacInputOffset(uuidOffset);
        fs.setSdmMacOffset(macOffset);

        ntag424DNA.changeFileSettings(FILE_NUMBER, fs);

        // Create NDEF record
        NdefRecordWrapper record = new NdefRecordWrapper(
                NdefRecordWrapper.TNF_WELL_KNOWN,
                type,
                new byte[0],  // empty ID
                jsonBytes     // payload (your JSON)
        );

        // Wrap record into NDEF message
        NdefMessageWrapper msg = new NdefMessageWrapper(record);

        ntag424DNA.writeNDEF(msg);

        NxpLogUtils.save();
    } catch (Exception e) {
        writeFailedMessage();
        mStringBuilder.append(e.getMessage());

        Log.i("MainActivity", "URI NDEF message written successful $msg " + e.getMessage()  );
        showMessage(mStringBuilder.toString(), PRINT);
        NxpLogUtils.save();
    }

}

如果有人能帮我解决这个问题，将是莫大的帮助

Re: How can i enable CMAC, UID, COUNTER and RAND in NTAG424 DNA?

谢谢您的帮助！你说得对，我的偏移值是错的。这就是我所做的更改，现在我可以保存设置了。

override fun onNewIntent(intent: Intent) {
    Log.i("NFC", "Intent action: ${intent.action}")
    super.onNewIntent(intent)

    Log.i("MainActivity", "NFC tag discovered")

    val cardType = libInstance.getCardType(intent)
    Log.i("MainActivity", "Detected card type: $cardType")
    if (cardType == CardType.NTAG424DNA) {
        val ntag424DNA: INTAG424DNA = DESFireFactory.getInstance().getNTAG424DNA(libInstance.customModules)
        val reader: IReader = ntag424DNA.reader

        try {

            if (!reader.isConnected) {
                reader.connect()
            }

            ntag424DNA.isoSelectApplicationByDFName(NTAG424DNA_APP_NAME)
            Log.i("NFC", "ISO selected app by DF Name ")

            authenticateTag(0x00, ntag424DNA, KEY_AES128_DEFAULT)
            creatingNDEFmessage(ntag424DNA)
            authenticateTag(0x00, ntag424DNA, KEY_AES128_DEFAULT)
            changeFileSettings(ntag424DNA, 0x02)

            if (reader.isConnected) {
                reader.close()
            }
        } catch (e: Exception) {
            Log.e("MainActivity", e.localizedMessage ?: "No Error Message");
            e.printStackTrace()
        }

    }
}

private fun changeFileSettings(ntag424DNA: INTAG424DNA, fileNumber: Int) {
    // 3. Create NTAG 424 DNA file settings for E104
    val fileSettings = NTAG424DNAFileSettings(
        MFPCard.CommunicationMode.Plain,    // = 0x03 = Full ENC + CMAC (SUN)
        0x0E.toByte(),             // Read access = key slot 0x00 maybe 0x01
        0x0E.toByte(),             // Write access = always
        0x0E.toByte(),             // RW access = always
        0x00.toByte()              // Change access = always
    )

    fileSettings.isSDMEnabled = true
    fileSettings.isUIDMirroringEnabled = true
    fileSettings.isSDMReadCounterEnabled = true
    fileSettings.sdmAccessRights = byteArrayOf(0xfe.toByte(), 0xe1.toByte())

    fileSettings.uidOffset = byteArrayOf(0x1A, 0x00, 0x00)   
    fileSettings.sdmReadCounterOffset = byteArrayOf(0x2d, 0x00, 0x00) 
    fileSettings.sdmMacOffset = byteArrayOf(0x39, 0x00, 0x00) 
    fileSettings.sdmMacInputOffset = byteArrayOf(0x39, 0x00, 0x00)

    Log.i("MainActivity", "Prepare for saving changes in file $fileNumber")

    ntag424DNA.changeFileSettings(fileNumber, fileSettings)
    Log.i("MainActivity", " File settings updated $fileNumber")
}

private fun creatingNDEFmessage(ntag424DNA: INTAG424DNA) {
    // 1. Creating URI NDEF message
    val payload = byteArrayOf(0x04) + "noexample.xxxx?uid=00000000000000&ctr=000000&cmac=0000000000000000".toByteArray()

    val msg = NdefMessageWrapper(
        NdefRecordWrapper(
            NdefRecordWrapper.TNF_WELL_KNOWN,
            "U".toByteArray(StandardCharsets.US_ASCII),
            ByteArray(0),
            payload
        )
    )

    ntag424DNA.writeNDEF(msg);
    Log.i("MainActivity", "URI NDEF message written successful ")

    val ndefRead = ntag424DNA.readNDEF()
    Log.i("MainActivity", "Read URI NDEF message ${CustomModules.getUtility().dumpBytes(ndefRead.toByteArray())}")

}

Re: How can i enable CMAC, UID, COUNTER and RAND in NTAG424 DNA?

亲爱的洛基2号

请查看 jimmyvhan 提供的文件和数据表。

你们的偏移量重叠了，而数据手册不允许这样做。

考虑您所需的 URL。存放 NFCCounter 的空间太少了，即 3 字节。因此，以下设置适合更正后的 URL。

https://domain.com?uid=04BB38D2AA1191&ctr=000001&cmac=3ab665b76b795cb9bf76a17956cc9fb3&rand=422def08...

您应将这些参数用于 SDM 配置。您还可以决定 CMAC 计算的输入数据。本例以 UIDOffset 为起点。

fileSettings.sdmMacOffset = intTo2ByteArray(53)
fileSettings.sdmMacInputOffset = intTo2ByteArray(22)
fileSettings.sdmReadCounterOffset = intTo2ByteArray(41)
fileSettings.uidOffset = intTo2ByteArray(22)

致以最崇高的敬意

TapLinx 团队

Re: How can i enable CMAC, UID, COUNTER and RAND in NTAG424 DNA?

本文件可能对您有用。

NTAG 424 DNA 和 NTAG 424 DNA TagTamper 功能和提示