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fix bug with false-positive crc16 and remove debug

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This commit is contained in:
merlokk 2021-07-09 14:01:57 +03:00
parent 77a66a024b
commit 08d8ac4f9f
1 changed files with 4 additions and 12 deletions
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16
client/src/mifare/desfirecrypto.c
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@ -117,21 +117,18 @@ size_t DesfireSearchCRCPos(uint8_t *data, size_t datalen, uint8_t respcode, uint
else
break;
crcpos++; // crc may be 0x00000000 or 0x0000
PrintAndLogEx(INFO, "crcpos: %d", crcpos);
if (crcpos < crclen) {
PrintAndLogEx(WARNING, "No space for crc. pos: %d", crcpos);
return 0;
}
uint8_t crcdata[1024] = {0};
bool crcok = false;
size_t crcposfound = 0;
for (int i = 0; i < crclen + 1; i++) {
PrintAndLogEx(INFO, "--crcpos: %d", crcpos - i);
if (crcpos - i == 0)
break;
if (crcpos - i + crclen > datalen)
continue;
PrintAndLogEx(INFO, "--crcposcheck: %d", crcpos - i);
memcpy(crcdata, data, crcpos - i);
crcdata[crcpos - i] = respcode;
@ -139,18 +136,13 @@ size_t DesfireSearchCRCPos(uint8_t *data, size_t datalen, uint8_t respcode, uint
if (crclen == 4)
res = desfire_crc32_check(crcdata, crcpos - i + 1, &data[crcpos - i]);
else
res = iso14443a_crc_check(crcdata, crcpos - i + 1, &data[crcpos - i]);
res = iso14443a_crc_check(data, crcpos - i, &data[crcpos - i]);
if (res) {
PrintAndLogEx(INFO, "--crc OK pos: %d", crcpos - i);
crcpos -= i;
crcok = true;
break;
crcposfound = crcpos - i;
}
}
if (!crcok)
crcpos = 0;
return crcpos;
return crcposfound;
}
static void DesfireCryptoEncDecSingleBlock(uint8_t *key, DesfireCryptoAlgorythm keyType, uint8_t *data, uint8_t *dstdata, uint8_t *ivect, bool dir_to_send, bool encode) {