github/RRG-Proxmark3
1
0
Fork 0
mirror of https://github.com/RfidResearchGroup/proxmark3.git synced 2025-08-22 06:13:51 -07:00
Code Issues Projects Releases Packages Wiki Activity Actions

Fix PAC/Stanley checksum calculation

Browse source 
The parity bit needs to be discarded when calculating the final
checksum byte value of PAC/Stanley card IDs. Verified by scanning
a tag which is now correctly identified.
This commit is contained in:
Richard Knoll 2021-08-28 14:28:06 +01:00
commit 7a6f503161
1 changed files with 1 additions and 1 deletions
Download patch file Download diff file Expand all files Collapse all files

2
client/src/cmdlfpac.c
View file

@ -54,7 +54,7 @@ static int pac_buf_to_cardid(uint8_t *src, const size_t src_size, uint8_t *dst,
PrintAndLogEx(DEBUG, "DEBUG: Error - PAC: Parity check failed"); PrintAndLogEx(DEBUG, "DEBUG: Error - PAC: Parity check failed");
return PM3_ESOFT; return PM3_ESOFT;
} }
if (idx < dataLength - 1) checksum ^= byte; if (idx < dataLength - 1) checksum ^= dst[idx];
} }
if (dst[dataLength - 1] != checksum) { if (dst[dataLength - 1] != checksum) {
PrintAndLogEx(DEBUG, "DEBUG: Error - PAC: Bad checksum - expected: %02X, actual: %02X", dst[dataLength - 1], checksum); PrintAndLogEx(DEBUG, "DEBUG: Error - PAC: Bad checksum - expected: %02X, actual: %02X", dst[dataLength - 1], checksum);