fix/update removeParity & fix securakey detection

[proxmark3-svn] / client / cmdlfsecurakey.c

diff --git a/client/cmdlfsecurakey.c b/client/cmdlfsecurakey.c
index 1d55faf91a6a08b9b96b0f13e78a5106f907ff98..1e3899db0732f76cb788724a25f402a374fc1ef5 100644 (file)
--- a/client/cmdlfsecurakey.c
+++ b/client/cmdlfsecurakey.c
@@ -83,33 +83,37 @@ int CmdSecurakeyDemod(const char *Cmd) {
        // y = card #
        // standard wiegand parities.
        // unknown checksum 11 bits? at the end
-       uint8_t bits_no_spacer[86];
-       memcpy(bits_no_spacer, DemodBuffer + 10, 86);
+       uint8_t bits_no_spacer[85];
+       memcpy(bits_no_spacer, DemodBuffer + 11, 85);
 
        // remove marker bits (0's every 9th digit after preamble) (pType = 3 (always 0s))
-       size = removeParity(bits_no_spacer, 0, 9, 3, 86);
-       if ( size != 86-10 ) {
+       size = removeParity(bits_no_spacer, 0, 9, 3, 85);
+       if ( size != 85-9 ) {
                if (g_debugMode) PrintAndLog("DEBUG: Error removeParity: %d", size);
                return 0;
        }
 
-       uint8_t bitLen = (uint8_t)bytebits_to_byte(DemodBuffer+2, 6);
+       uint8_t bitLen = (uint8_t)bytebits_to_byte(bits_no_spacer+2, 6);
        uint32_t fc=0, lWiegand=0, rWiegand=0;
-       // get FC
+       if (bitLen > 40) { //securakey's max bitlen is 40 bits...
+               if (g_debugMode) PrintAndLog("DEBUG: Error bitLen too long: %u", bitLen);
+               return 0;
+       }
        // get left 1/2 wiegand & right 1/2 wiegand (for parity test and wiegand print)
-       lWiegand = bytebits_to_byte(DemodBuffer + 48 - bitLen, bitLen/2);
-       rWiegand = bytebits_to_byte(DemodBuffer + 48 - bitLen + bitLen/2, bitLen/2);
-       fc = bytebits_to_byte(DemodBuffer+49-bitLen, bitLen-2-16);
+       lWiegand = bytebits_to_byte(bits_no_spacer + 48 - bitLen, bitLen/2);
+       rWiegand = bytebits_to_byte(bits_no_spacer + 48 - bitLen + bitLen/2, bitLen/2);
+       // get FC
+       fc = bytebits_to_byte(bits_no_spacer+49-bitLen, bitLen-2-16);
 
        // test bitLen
        if (bitLen != 26 && bitLen != 32)
                PrintAndLog("***unknown securakey bitLen - share with forum***");
 
-       uint32_t cardid = bytebits_to_byte(DemodBuffer+8+23, 16);
-       // test parities
-       bool parity = evenparity32(lWiegand) && oddparity32(rWiegand);
+       uint32_t cardid = bytebits_to_byte(bits_no_spacer+8+23, 16);
+       // test parities - evenparity32 looks to add an even parity returns 0 if already even...
+       bool parity = !evenparity32(lWiegand) && !oddparity32(rWiegand);
 
-       PrintAndLog("Securakey Tag Found--BitLen: %u, Card ID: %u, FC: %X, Raw: %08X%08X%08X", bitLen, cardid, fc, raw1 ,raw2, raw3);
+       PrintAndLog("Securakey Tag Found--BitLen: %u, Card ID: %u, FC: 0x%X, Raw: %08X%08X%08X", bitLen, cardid, fc, raw1 ,raw2, raw3);
        if (bitLen <= 32)
                PrintAndLog("Wiegand: %08X, Parity: %s", (lWiegand<<(bitLen/2)) | rWiegand, parity ? "Passed" : "Failed");
        PrintAndLog("\nHow the FC translates to printed FC is unknown");