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Use a lower-level communication with Mifare DESFire targets.

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Instead of uting nfc_initiator_transceive_dep_bytes() to transmit commands,
prepend an ISO-14443-4 header to it and send it using
nfc_initiator_transceive_bytes().  In case of WTX reply, handle it, and then
extract relevant information from the data returned by the PICC.

This prevents failure that happen with ISO-14443-4 compliant targets when using
a PN531-based NFC-device, and allows using the libfreefare with Mifare DESFire
targets on such devices.
This commit is contained in:
Romain Tartiere 2010-07-29 09:48:08 +00:00
parent 02897e1b69
commit 88a4cbbe53
1 changed files with 27 additions and 4 deletions
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31
libfreefare/mifare_desfire.c
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@ -102,18 +102,41 @@ static ssize_t read_data (MifareTag tag, uint8_t command, uint8_t file_no, off_
* Convenience macros.
*/
/*
* Since we will have to deal with a 1-byte headers for all transmissions,
* redefine the BUFFER_INIT macro.
*/
#undef BUFFER_INIT
#define BUFFER_INIT(buffer_name, size) \
uint8_t __##buffer_name[size+1] = { 0x02 }; \
uint8_t *buffer_name = &(__##buffer_name[1]); \
size_t __##buffer_name##_n = 0
/*
* Transmit the message msg to the NFC tag and receive the response res. The
* response buffer's size is set according to the quantity od data received.
* response buffer's size is set according to the quantity of data received.
*
* This macro takes care of handling wait-time extension (WTX) requests defined
* by ISO-14443-4.
*/
#define DESFIRE_TRANSCEIVE(tag, msg, res) \
do { \
errno = 0; \
MIFARE_DESFIRE (tag)->last_picc_error = OPERATION_OK; \
DEBUG_XFER (msg, __##msg##_n, "===> "); \
if (!(nfc_initiator_transceive_dep_bytes (tag->device, msg, __##msg##_n, res, &__##res##_n))) \
DEBUG_XFER (__##msg, __##msg##_n+1, "===> "); \
if (!(nfc_initiator_transceive_bytes (tag->device, __##msg, __##msg##_n+1, __##res, &__##res##_n))) \
return errno = EIO, -1; \
DEBUG_XFER (res, __##res##_n, "<=== "); \
DEBUG_XFER (__##res, __##res##_n, "<=== "); \
__##res##_n -= 1; \
while (__##res[0] == 0xf2) { \
uint8_t ack[2] = { 0xf2, 0x00 }; \
ack[1] |= __##res[1] & 0x3f; \
__##res##_n = 0; \
DEBUG_XFER (ack, 2, "===> "); \
nfc_initiator_transceive_bytes (tag->device, ack, 2, __##res, &__##res##_n); \
DEBUG_XFER (__##res, __##res##_n, "<=== "); \
__##res##_n -= 1; \
} \
if ((1 == __##res##_n) && (OPERATION_OK != res[0]) && (ADDITIONAL_FRAME != res[0])) \
return MIFARE_DESFIRE (tag)->last_picc_error = res[0], -1; \
} while (0)