I'm attempting to lock a Mifare Ultralight C tag. I want to set NDEF pages 0x04 to 0x27 to read-only. I think this can be achieved via Ndef.makeReadonly().
Additionally, I would like to set pages 0x29 to 0x2F to be password protected (for read and write) so they can only be accessed after authentication was successful. I'm struggling to understand which bytes need to set in lock bytes (page 0x28, bytes 0, 1) and if sectors 0x2A and 0x2B need to be set as well.
I'm attempting to set NDEF pages 0x04 to 0x27 to readonly. I think this can be achieved via Ndef.makeReadonly().
Not necessarily, Ndef.makeReadonly() might only set the read-only flag in the capability container (according to the NFC Forum Type 2 Tag Operation specification).
If you want to make sure to set the actual lock bits, you would connect the tag as NfcA or MifareUltralight tag technology and issue a write command for the lock bits instead.
NfcA nfcA = NfcA.get(tag);
nfcA.connect();
byte[] result1 = nfcA.transceive(new byte[] {
(byte)0xA2, /* CMD = WRITE */
(byte)0x02, /* PAGE = 2 */
(byte)0x00, (byte)0x00, (byte)0xFF, (byte)0xFF /* DATA = lock pages 3..15 */
});
byte[] result2 = nfcA.transceive(new byte[] {
(byte)0xA2, /* CMD = WRITE */
(byte)0x28, /* PAGE = 40 */
(byte)0x0F, (byte)0x00, (byte)0x00, (byte)0x00 /* DATA = lock pages 16..27 */
});
Also see Mifare Ultralight: lock specific pages for the coding of the lockbits.
I would like to set pages 0x29 to 0x2F to be password protected (for read and write) so they can only be accessed after authentication was successful.
Using the write command that I showed above, you would first write your authentication key into pages 44..47. You would then write AUTH1 (page 43) as all-zeros. Finally, you would write AUTH0 (page 42) as 0x29 0x00 0x00 0x00 to require authentication for pages 41 and up. Actually I would suggest to lock pages 40 and up so that nobody could set the lock bits for those pages. Alternatively, you could set the block locking bits (i.e. write 0x1F 0x0F 0x00 0x00 to page 40) so that the lock bits for the unlocked pages cannot be changed.
Related
I will explain my project :
I have my RC522 and a door connected on my Arduino UNO.
I can currently open the door with a MIFARE classic.
But now I want to open it with my Android smartphone, this is why I develop a HCE applet to accept the good APDU with the selected AID, then my phone will transfer the data in order to open the door.
But the problem is :
I don't know how to send an APDU command with my Arduino using the RC522.
Currently, for my MIFARE Cards, I use the https://github.com/miguelbalboa/rfid library.
My test code :
byte selectApdu[] = {
0x00, /* CLA */
0xA4, /* INS */
0x04, /* P1 */
0x00, /* P2 */
0x05, /* Length of AID */
0xF2, 0x22, 0x22, 0x22, 0x22,
};
byte * backData = (byte *)malloc(16*sizeof(byte));
byte * dataLen = (byte *)16;
status = mfrc522.PCD_TransceiveData(selectApdu,10,backData,dataLen,NULL,0,false);
if ( status != MFRC522::STATUS_OK) {
Serial.print(F("PCD_TransceiveData() failed: "));
Serial.println(mfrc522.GetStatusCodeName(status));
return;
}
else
{
Serial.println(F("PICC_TransceiveData() success "));
}
Neverless, it doesn't work ( "Timeout in communication"), and I slowly need to think that the RC522 is not compatible...
It's an (well commented) open-source project. Just have a look to source code, for instance If you use MIFARE_Read function of MFRC522.cpp
MFRC522::StatusCode MFRC522::MIFARE_Read( byte blockAddr, ///< MIFARE Classic: The block (0-0xff) number. MIFARE Ultralight: The first page to return data from.
byte *buffer, ///< The buffer to store the data in
byte *bufferSize ///< Buffer size, at least 18 bytes. Also number of bytes returned if STATUS_OK.
) {
MFRC522::StatusCode result;
// Sanity check
if (buffer == NULL || *bufferSize < 18) {
return STATUS_NO_ROOM;
}
// Build command buffer
buffer[0] = PICC_CMD_MF_READ;
buffer[1] = blockAddr;
// Calculate CRC_A
result = PCD_CalculateCRC(buffer, 2, &buffer[2]);
if (result != STATUS_OK) {
return result;
}
// Transmit the buffer and receive the response, validate CRC_A.
return PCD_TransceiveData(buffer, 4, buffer, bufferSize, NULL, 0, true);
} // End MIFARE_Read()
You could see function PCD_TransceiveData is called and check source of this function:
/**
* Executes the Transceive command.
* CRC validation can only be done if backData and backLen are specified.
*
* #return STATUS_OK on success, STATUS_??? otherwise.
*/
MFRC522::StatusCode MFRC522::PCD_TransceiveData( byte *sendData, ///< Pointer to the data to transfer to the FIFO.
byte sendLen, ///< Number of bytes to transfer to the FIFO.
byte *backData, ///< NULL or pointer to buffer if data should be read back after executing the command.
byte *backLen, ///< In: Max number of bytes to write to *backData. Out: The number of bytes returned.
byte *validBits, ///< In/Out: The number of valid bits in the last byte. 0 for 8 valid bits. Default NULL.
byte rxAlign, ///< In: Defines the bit position in backData[0] for the first bit received. Default 0.
bool checkCRC ///< In: True => The last two bytes of the response is assumed to be a CRC_A that must be validated.
) {
byte waitIRq = 0x30; // RxIRq and IdleIRq
return PCD_CommunicateWithPICC(PCD_Transceive, waitIRq, sendData, sendLen, backData, backLen, validBits, rxAlign, checkCRC);
} // End PCD_TransceiveData()
You could called PCD_TransceiveData or PCD_CommunicateWithPICC functions.
UPDATE
You put 0 values for parameters: "backData", "backLen", and "validBits".
validBits could be null.
backData and backLen must be defined as byte.
UPDATE2
If you have a look at library support protocols It supports ISO/IEC 14443-3 (type A) and not supports ISO/IEC 14443-4 (type B).
If you have a look at Android HCE documentation :
Specifically, Android 4.4 supports emulating cards that are based on
the NFC-Forum ISO-DEP specification (based on ISO/IEC 14443-4) and
process Application Protocol Data Units (APDUs) as defined in the
ISO/IEC 7816-4 specification. Android mandates emulating ISO-DEP only
on top of the Nfc-A (ISO/IEC 14443-3 Type A) technology. Support for
Nfc-B (ISO/IEC 14443-4 Type B) technology is optional. The layering of
all these specifications is shown in the figure 3
In this post: HCE support for ISO/IEC 14443-3 Type B?
Looking at devices in the field, some devices use Type A for HCE and
some seem to use Type B. So it's basically the device manufacturer who
decides if Type A or Type B is used. The Android API provides no means
for the app developer to influence this.
So you have to check with another Android NFC device if your device emulate ISO/IEC 14443-3 (Type A) or ISO/IEC 14443-4 (Type B). You could use NfcTagInfo application on other android device to check this.
I need to develop an Android app that is able to read an NfcV tag containing about 8 kByte of binary data. A single tag block is 8 bytes.
I wrote following code:
for (int i = 0; i < 256; ++i)
{
byte[] cmd = new byte[] {
0x02,
0x20,
(byte)i // Block number
};
byte[] block = nfcV.transceive(cmd);
for(int j = 0; j < 8; ++j) this.sensorData[i * 8 + j] = block[j + 1];
}
But this lets me only read the first 2 kByte of the tag (256 blocks of 8 bytes).
How can I read all 8 kByte?
Unfortunately I have few info about the Tag. I know that it's made by Texas Instruments, and Taginfo app says that it's compatible with
ISO/IEC 15693-3 and ISO/IEC 15693-2.
You are using the READ SINGLE BLOCK command (command code 0x20) to read from an ISO/IEC 15693 tag. The standard only defines the READ SINGLE BLOCK command for block addresses from 0 to 255. Hence, since your tag seems to have a block size of 8 bytes, this command limits you to the first 2 KB of the tag memory.
Reading beyond this address space is not defined by the ISO/IEC 15693 standard. Hence, this depends on the tag type that you use and you should therefore consult the user manual of your tag. Some tag manufacturers overcome this address-space limitation by defining a protocol extension (see Protocol_Extension_flag in the request flags byte of the command)
byte[] cmd = new byte[]{
(byte)0x08, //Protocol_Extension_flag=1
(byte)0x20, //READ SINGLE BLOCK
(byte)(address & 0x00FF), (byte)((address>>8) & 0x00FF)
};
However, this will only work if your tag supports this specific protocol extension. Depending on your tag type, it's also possible, that the tag uses some other method to address the remaining memory.
Also note that several Android devices will not properly work with unaddressed ISO/IEC 15693 commands. Thus, it's typically better to stick to the addressed version of commands. The addressed version of the above command (Addressed_flag set and UID of tag included in command) would like this:
byte tagId = nfcV.getTag().getId();
byte[] cmd = new byte[]{
(byte)0x28, //Addressed_flag=1, Protocol_Extension_flag=1
(byte)0x20, //READ SINGLE BLOCK
(byte)0x00, (byte)0x00, (byte)0x00, (byte)0x00, (byte)0x00, (byte)0x00, (byte)0x00, (byte)0x00, // placeholder for UID
(byte)(address & 0x00FF), (byte)((address>>8) & 0x00FF)
};
System.arraycopy(tagId, 0, cmd, 2, 8);
In both of the above cases, you could try variations of the Data_rate_flag (second lowest bit of the flags byte) and the Sub-carrier_flag (lowest bit of the flags byte), though I'm unsure how different Android devices will handle this.
I'm having a problem in my application with the MifareClassic.autenticateSectorWithKeyA(int sector, byte[] keyA) method. I have tried many ways but it dose not authenticate.
My key A is:
byte[] key = new byte[] { (byte) 0x3c, (byte) 0x55, (byte) 0x28,
(byte) 0x12, (byte) 0x5c, (byte) 0x61, (byte) 0x00,
(byte) 0x5C, (byte) 0x71, (byte) 0x00 };
What does each byte in this key represent?
If I have a key like 3c5528125c61 as above, how should I write the byte array to authenticate, read block 2 and get the bytes?
What is an AID (Application code)? When should I use it?
Your key byte array does not make much sense as a MIFARE Classic key. A key for MIFARE Classic consists of only 6 bytes. Hence, this would be a possible value for key:
byte[] key = new byte[] { (byte)0x3c, (byte)0x55, (byte)0x28,
(byte)0x12, (byte)0x5c, (byte)0x61 };
How do I authenticate to a sector and read a data block?
In order to read block 2 (and assuming that it is readable after authenticationg with the above key), you would do something like the following:
Authenticate to the sector that contains the block to read (block 2 is located in sector 0, you can use the helber method MifareClassic.blockToSector() to obtain the sector number for a given block number.
If authentication was successful, you can read the block.
final MifareClassic mfc = MifareClassic.get(tag);
mfc.connect();
final int blockNumber = 2;
if (mfc.authenticateSectorWithKeyA(mfc.blockToSector(blockNumber), key)) {
final byte[] data = mfc.readBlock(blockNumber)
// TODO: do something with data
}
mfc.close();
What is AID (Application Identifier)? and when should I use it?
MIFARE Classic itself has a linear memory layout. I.e. one that is addressed based on block numbers, where each block contains 16 bytes. These blocks are grouped into sectors with individual access conditions and keys.
In order to logically assign this data (the sectors/groups of blocks) to specific applications (e.g. some data for a physical access control system, some data for an electronic purse, etc.) and, hence, to use one card for more that one application at the same time, the MIFARE Application Directory (MAD) was introduced. The MAD is basically a lookup table (located in sector 0 for MIFARE Classic 1K and in sectors 0 and 16 for MIFARE Classic 4K). This lookup table maps each sector of the card to one application. Applications are identified though a two byte value, the MIFARE application identifier (AID). Thus, if a card uses the MAD, an application can lookup its data sectors by browsing the MAD for its AID.
I'm trying to authenticate any sector of a MIFARE classic card. I'm using a twinlinx mymax sticker (which makes almost any bluetooth device NFC enabled). It sends commands to a connected NFC tag. I've already made a connection and sent and recieved data with a Ultralight C tag, but so far I had no success on accessing a Mifare Classic. Here is my authentication code:
private boolean authenticate(int sector, byte[] key, boolean keyA) {
byte[] cmd = new byte[12];
// First byte is the command
if (keyA) {
cmd[0] = 0x60; // phHal_eMifareAuthentA
} else {
cmd[0] = 0x61; // phHal_eMifareAuthentB
}
// Second byte is block address
cmd[1] = (byte) 0x03;
// Next 6 bytes are the key
System.arraycopy(key, 0, cmd, 2, 6);
// Next 4 bytes is the UID
System.arraycopy(Answer, 3, cmd, 8,4);
byte[] test = null;
//this makes a connection to the NFC tag (and this works)
TR.ConnectToExternalCard(AUTH, (byte)0x00);
//checking if the tag is still connected
if (TR.isCardPresent() == true){
//sending command to authenticate
test = TR.SendCommandPropAndWaitResponse(cmd, (byte) 0x00);
}
try {
if (test != null) {
return true;
}
}
I'm using standard MIFARE Classic keys, the tags are fresh from the factory. The complete command (in bytes) which is sent to the tag is:
[0x60, 0x3, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xf3, 0xf4, 0xa9, 0xfb]
Any Ideas? The tag seems to be non-responsive... tried accessing other Classic tags but also had no success. Thanks!
It is hard to say what you are doing wrong using an SDK that is not publicly available. However, the API looks familiar enough, so I will give it a try anyway. I can think of a number of things you may try (in decreasing order of likeliness):
The UID bytes may be in the wrong order, so try reversing them.
Perhaps Answer does not only contain the UID, but other bytes, too (e.g. SAK), and you are copying the wrong bytes from it.
The MIFARE Classic tags you have may have a 7-byte UID and you are not using the correct 4 bytes from that.
May be TR.SendCommandPropAndWaitResponse() is the wrong method to use. Perhaps there is a dedicated method for MIFARE Classic.
The MyMax sticker may not support MIFARE Classic. I don't see explicit confirmation on their website that they do. However, indications are that their solution is based on NXP hardware, which always supports MIFARE Classic.
i write some data (NDEF) into Mifare Ultralight Tag. Then the tag is set to read only with Ndef.MakeReadOnly(). The Tag seems to be read only afterwards.
But reading the Tag content shows, that only pages (4-15, Lx bytes are set to 1) are locked, the three BLx Bytes are left 0. When i got it right, this means that Pages Locks could be altered again. Page 2, Bytes 2 = 11111000, Page 2 Byte 3 = 11111111 - (see http://www.nxp.com/documents/data_sheet/MF0ICU1.pdf , page 12).
Is there a way to make the tag permanently write protected?
Thanks for your time.
To make the whole tag read only, you could get the tag again as a MifareUltralight instead of as a Ndef. Then you do
MifareUltralightTag.writePage(2,new byte[] {0x00, 0x00, 0xFF, 0xFF});
followed by
MifareUltralightTag.transceive(new byte[] {0x26});
to "activate the new locking configuration."