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acr122_usb: Fixes CCID reply decoding.

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This commit is contained in:
Romuald Conty 2012-10-04 09:35:47 +00:00
parent 26dabba7ac
commit b27f8634d6
1 changed files with 13 additions and 19 deletions
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32
libnfc/drivers/acr122_usb.c
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@ -713,37 +713,31 @@ read:
} }
offset++; offset++;
// XXX In CCID specification, len is a 32-bits (dword), do we need to decode more than 1 byte ? (0-255 bytes for PN532 reply)
len = abtRxBuf[offset++]; len = abtRxBuf[offset++];
if ((abtRxBuf[++] != 0x00) && (abtRxBuf[++] != 0x00) && (abtRxBuf[++] != 0x00)) {
log_put(LOG_CATEGORY, NFC_PRIORITY_ERROR, "%s", "Not implemented: only 1-byte length is supported, please report this bug with a full trace.");
pnd->last_error = NFC_EIO;
return pnd->last_error;
}
if (len < 4) { if (len < 4) {
log_put(LOG_CATEGORY, NFC_PRIORITY_ERROR, "%s", "Too small reply"); log_put(LOG_CATEGORY, NFC_PRIORITY_ERROR, "%s", "Too small reply");
pnd->last_error = NFC_EIO; pnd->last_error = NFC_EIO;
return pnd->last_error; return pnd->last_error;
} }
len -= 4; len -= 4; // We skip 2 bytes for PN532 direction byte (D5) and command byte (CMD+1), then 2 bytes for APDU status (90 00).
if (len > szDataLen) { if (len > szDataLen) {
log_put(LOG_CATEGORY, NFC_PRIORITY_ERROR, "Unable to receive data: buffer too small. (szDataLen: %zu, len: %zu)", szDataLen, len); log_put(LOG_CATEGORY, NFC_PRIORITY_ERROR, "Unable to receive data: buffer too small. (szDataLen: %zu, len: %zu)", szDataLen, len);
pnd->last_error = NFC_EIO; pnd->last_error = NFC_EOVFLOW;
return pnd->last_error; return pnd->last_error;
} }
switch(DRIVER_DATA(pnd)->model) { // Skip CCID remaining bytes
case TOUCHATAG: offset += 2; // bSlot and bSeq are not used
offset += 8; // Skip CCID remaining bytes offset += 2; // XXX bStatus and bError should maybe checked ?
break; offset += 1; // bRFU should be 0x00
case ACR122:
{
const uint8_t acr122_preamble[] = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0x81, 0x00 };
if (0 != (memcmp(abtRxBuf + offset, acr122_preamble, sizeof(acr122_preamble)))) {
log_put(LOG_CATEGORY, NFC_PRIORITY_ERROR, "%s", "Frame preamble mismatch");
pnd->last_error = NFC_EIO;
return pnd->last_error;
}
offset += sizeof(acr122_preamble);
} break;
case UNKNOWN:
break;
}
// TFI + PD0 (CC+1) // TFI + PD0 (CC+1)
if (abtRxBuf[offset] != 0xD5) { if (abtRxBuf[offset] != 0xD5) {