NfcTag MifareUltralight::read(byte * uid, unsigned int uidLength)
{
if (isUnformatted())
{
Serial.println(F("WARNING: Tag is not formatted."));
return NfcTag(uid, uidLength, NFC_FORUM_TAG_TYPE_2);
}
readCapabilityContainer(); // meta info for tag
findNdefMessage();
calculateBufferSize();
if (messageLength == 0) { // data is 0x44 0x03 0x00 0xFE
NdefMessage message = NdefMessage();
message.addEmptyRecord();
return NfcTag(uid, uidLength, NFC_FORUM_TAG_TYPE_2, message);
}
boolean success;
uint8_t page;
uint8_t index = 0;
byte buffer[bufferSize];
for (page = ULTRALIGHT_DATA_START_PAGE; page < ULTRALIGHT_MAX_PAGE; page++)
{
// read the data
success = nfc->mifareultralight_ReadPage(page, &buffer[index]);
if (success)
{
#ifdef MIFARE_ULTRALIGHT_DEBUG
Serial.print(F("Page "));
Serial.print(page);
Serial.print(" ");
nfc->PrintHexChar(&buffer[index], ULTRALIGHT_PAGE_SIZE);
#endif
}
else
{
Serial.print(F("Read failed "));
Serial.println(page);
// TODO error handling
messageLength = 0;
break;
}
if (index >= (messageLength + ndefStartIndex))
{
break;
}
index += ULTRALIGHT_PAGE_SIZE;
}
NdefMessage ndefMessage = NdefMessage(&buffer[ndefStartIndex], messageLength);
return NfcTag(uid, uidLength, NFC_FORUM_TAG_TYPE_2, ndefMessage);
}
NfcTag NfcAdapter::read()
{
uint8_t type = guessTagType();
// TODO need an abstraction of Driver
if (type == TAG_TYPE_MIFARE_CLASSIC)
{
#ifdef NDEF_DEBUG
DMSG("Reading Mifare Classic");
#endif
MifareClassic mifareClassic = MifareClassic(*shield);
return mifareClassic.read(uid, uidLength);
}
else if (type == TAG_TYPE_2)
{
#ifdef NDEF_DEBUG
DMSG("Reading Mifare Ultralight");
#endif
MifareUltralight ultralight = MifareUltralight(*shield);
return ultralight.read(uid, uidLength);
}
else if (type == TAG_TYPE_UNKNOWN)
{
DMSG("Can not determine tag type");
//DMSG("Can not determine tag type for ATQA 0x");
//Serial.print(atqa, HEX);DMSG(" SAK 0x");DMSG(sak, HEX);
return NfcTag(uid, uidLength);
}
else
{
DMSG("No driver for card type ");
DMSG_INT(type);
// TODO should set type here
return NfcTag(uid, uidLength);
}
}
NfcTag MifareClassic::read(byte *uid, unsigned int uidLength)
{
uint8_t key[6] = { 0xD3, 0xF7, 0xD3, 0xF7, 0xD3, 0xF7 };
int currentBlock = 4;
int messageLength = 0;
byte data[BLOCK_SIZE];
// read first block to get message length
int success = _nfcShield->mifareclassic_AuthenticateBlock(uid, uidLength, currentBlock, 0, key);
if (success)
{
success = _nfcShield->mifareclassic_ReadDataBlock(currentBlock, data);
if (success)
{
messageLength = getNdefLength(data);
if (messageLength < 1) {
return NfcTag(uid, uidLength, "ERROR"); // TODO should the error message go in NfcTag?
}
}
else
{
// TODO why is an unformatted tag ending up here? Authentication should have failed.
Serial.print(F("Error. Failed read block "));Serial.println(currentBlock);
return NfcTag(uid, uidLength, MIFARE_CLASSIC);
}
}
else
{
Serial.print(F("Error. Block Authentication failed for "));Serial.println(currentBlock);
// TODO unformatted tags should be ending up here
// TODO set tag.isFormatted = false
return NfcTag(uid, uidLength, MIFARE_CLASSIC);
}
// this should be nested in the message length loop
int index = 0;
int bufferSize = getBufferSize(messageLength);
uint8_t buffer[bufferSize];
#ifdef MIFARE_CLASSIC_DEBUG
Serial.print(F("Message Length "));Serial.println(messageLength);
Serial.print(F("Buffer Size "));Serial.println(bufferSize);
#endif
while (index < bufferSize)
{
// authenticate on every sector
if (_nfcShield->mifareclassic_IsFirstBlock(currentBlock))
{
success = _nfcShield->mifareclassic_AuthenticateBlock(uid, uidLength, currentBlock, 0, key);
if (!success)
{
Serial.print(F("Error. Block Authentication failed for "));Serial.println(currentBlock);
// TODO error handling
}
}
// read the data
success = _nfcShield->mifareclassic_ReadDataBlock(currentBlock, &buffer[index]);
if (success)
{
#ifdef MIFARE_CLASSIC_DEBUG
Serial.print(F("Block "));Serial.print(currentBlock);Serial.print(" ");
_nfcShield->PrintHexChar(&buffer[index], BLOCK_SIZE);
#endif
}
else
{
Serial.print(F("Read failed "));Serial.println(currentBlock);
// TODO handle errors here
}
index += BLOCK_SIZE;
currentBlock++;
// skip the trailer block
if (_nfcShield->mifareclassic_IsTrailerBlock(currentBlock))
{
#ifdef MIFARE_CLASSIC_DEBUG
Serial.print(F("Skipping block "));Serial.println(currentBlock);
#endif
currentBlock++;
}
}
// NdefMessage ndefMessage = NdefMessage(&buffer[4], messageLength);
// NfcTag tag = NfcTag(uid, uidLength, "Mifare Classic", ndefMessage);
// return tag;
return NfcTag(uid, uidLength, MIFARE_CLASSIC, &buffer[4], messageLength);
}
