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I am creating a java application communicating with a Mifare DESFire card through a PC/SC contactless reader and the javax.smartcardio API. I manage to send regular ISO 7816 APDUs (CLA, INS, P1-P2, Lc, Command data, Le).

I have read on Ridrix's Blog that DESFire cards (at least the EV1 version that I am using) support both APDUs and Native commands where most of the commands are only 1 byte long.

For example, the "Get Version" command:

Command: 60
Response: af 04 01 01 00 02 18 05

I tested that command with the PC/SC Diag program from SpringCard (available here) and I get a correct response.

But I cannot send this command with javax.smartcardio: this API seems to have been created for real APDUs and therefore does not allow 1 byte long commands.

Here is what I did:

public static void main(String[] args){
    TerminalFactory factory = TerminalFactory.getDefault();
    CardTerminals terminalList = factory.terminals();

    try {
        CardTerminal ct = terminalList.list().get(0);       
        ct.waitForCardPresent(0);
        Card card = ct.connect("*");
        CardChannel channel = card.getBasicChannel();

        byte[] command = { 0x60 };

        channel.transmit(new CommandAPDU(command));
    } catch (CardException e) {
        e.printStackTrace();
    }
}

It gives me the following error:

Exception in thread "main" java.lang.IllegalArgumentException: apdu must be at least 4 bytes long
    at javax.smartcardio.CommandAPDU.parse(Unknown Source)
    at javax.smartcardio.CommandAPDU.<init>(Unknown Source)

I tried the only (AFAIK) other way to send a command:

        ByteBuffer command = ByteBuffer.allocate(1);
        command.put((byte) 0x60);

        ByteBuffer response = ByteBuffer.allocate(512);

        channel.transmit(command, response);

and get a similar error:

Exception in thread "main" java.lang.IllegalArgumentException: Command APDU must be at least 4 bytes long
    at sun.security.smartcardio.ChannelImpl.checkManageChannel(Unknown Source)
    at sun.security.smartcardio.ChannelImpl.doTransmit(Unknown Source)
    at sun.security.smartcardio.ChannelImpl.transmit(Unknown Source)

Do you know of any way to send this kind of command using javax.smartcardio or something else?

I know it is possible to wrap these commands but I would prefer to use the (simpler) native commands.

Thanks.

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3 回答 3

3

javax.smartcardio是为使用 ISO 7816-4 命令而编写的 API。因此，不可能发送“本机”命令。基本上，本机命令可以是任何东西，因此很难支持它们。

要么您恢复到 JNI，要么您可能会尝试找到使用transmitControlCommand. 但恐怕没有额外的库就没有真正的方式来使用 DESFire。

我个人认为使用包裹层要容易得多。

于 2012-07-28T00:10:42.717 回答
3

将近 4 年后，但以防万一有人对这个问题存有疑问，我确实找到了答案。今天的许多读者支持将 Desfire APDU 帧包装在 ISO 7816-4 命令中。我确实发现了数据不能超过 55 个字节的限制。

查看此文档中的第 23 页以获取完整信息： http: //neteril.org/files/M075031_desfire.pdf

这意味着您可以指定以下内容来包装 APDU 帧

CLA = 0x90
INC = {Your Desfire Command e.g. 0x60 - Get Version}
P1 = 0
P2 = 0
Data = 1st byte = length of data followed by byte data. Terminate data with a 0x00 byte

响应也包装如下：

SW1 = 0x91
SW2 = Result Status
Data = Response Data

所以可以使用下面的代码

public static byte CMD_WRAP_START = (byte)0x90;
public static byte CMD_WRAP_END = (byte)0x00;

private CommandAPDU wrapAPDUFrameUsingISO7816_4(byte[] apdu) throws CardException {
    if (apdu.length > 55){
        throw new CardException("The length of the wrapped DESFire command must not be longer than 55 bytes, checksum included.");
    }
    boolean hasData = apdu.length > 1;
    byte[] result;
    if (hasData) {
        result = new byte[apdu.length + 5];
    } else {
        result = new byte[apdu.length + 4];
    }
    result[0] = CMD_WRAP_START; // CLA
    result[1] = apdu[0];        // DESFIRE CMD CODE
    result[2] = 0;              // P1
    result[3] = 0;              // P2
    if (hasData) {
        result[4] = (byte) (apdu.length - 1);  // Length of wrapped data, ONLY IF DATA EXISTS
        System.arraycopy(apdu,1,result,5,apdu.length-1); // DESFIRE Command data
    }
    result[result.length-1] = CMD_WRAP_END;
    return new CommandAPDU(result);
}

private static byte [] unwrapFromISO7816_4(byte[] wrapped) throws CardException {
    if (wrapped.length<2){
        throw new CardException("Expected at least 2 bytes for ISO 7816-4 wrapped response: " + String.valueOf(Hex.encodeHex(wrapped, false)));
    }
    if (wrapped[wrapped.length-2]!=(byte)0x91){
        throw new CardException("Expected 0x91 in SW1 for ISO 7816-4 wrapped response: " + String.valueOf(Hex.encodeHex(wrapped, false)));
    }
    byte[] result = new byte[wrapped.length-1];
    System.arraycopy(wrapped,0,result,1,wrapped.length-2);  // The DESFIRE response
    result[0] = wrapped[wrapped.length-1];  // The DESFIRE Status
    return result;
}
于 2017-01-18T21:14:14.613 回答
1

在这里您有答案：命令 APDU 必须至少为 4 个字节。

     * case 1 : |CLA|INS|P1 |P2 |                    len = 4 
     * case 2s: |CLA|INS|P1 |P2 |LE |                len = 5 
     * case 3s: |CLA|INS|P1 |P2 |LC |...BODY...|     len = 6..260 
     * case 4s: |CLA|INS|P1 |P2 |LC |...BODY...|LE | len = 7..261
     *
     * (Extended length is not currently supported) 
     * case 2e: |CLA|INS|P1 |P2|00 |LE1|LE2|                    len = 7 
     * case 3e: |CLA|INS|P1 |P2 |00|LC1|LC2|...BODY...|         len = 8..65542 
     * case 4e: |CLA|INS|P1 |P2 |00|LC1|LC2|...BODY...|LE1|LE2| len =10..65544
     *
     * EMV
于 2013-02-13T19:11:36.470 回答