+//by marshmellow
+// - ASK Demod then Biphase decode GraphBuffer samples
+int ASKbiphaseDemod(const char *Cmd, bool verbose)
+{
+ //ask raw demod GraphBuffer first
+ int offset=0, clk=0, invert=0, maxErr=0, ans=0;
+ ans = sscanf(Cmd, "%i %i %i %i", &offset, &clk, &invert, &maxErr);
+ if (ans>0)
+ ans = ASKrawDemod(Cmd+2, FALSE);
+ else
+ ans = ASKrawDemod(Cmd, FALSE);
+ if (!ans) {
+ if (g_debugMode || verbose) PrintAndLog("Error AskrawDemod: %d", ans);
+ return 0;
+ }
+
+ //attempt to Biphase decode DemodBuffer
+ size_t size = DemodBufferLen;
+ uint8_t BitStream[MAX_DEMOD_BUF_LEN];
+ memcpy(BitStream, DemodBuffer, DemodBufferLen);
+
+ int errCnt = BiphaseRawDecode(BitStream, &size, offset, invert);
+ if (errCnt < 0){
+ if (g_debugMode || verbose) PrintAndLog("Error BiphaseRawDecode: %d", errCnt);
+ return 0;
+ }
+ if (errCnt > maxErr) {
+ if (g_debugMode || verbose) PrintAndLog("Error BiphaseRawDecode too many errors: %d", errCnt);
+ return 0;
+ }
+ //success set DemodBuffer and return
+ setDemodBuf(BitStream, size, 0);
+ if (g_debugMode || verbose){
+ PrintAndLog("Biphase Decoded using offset: %d - # errors:%d - data:",offset,errCnt);
+ printDemodBuff();
+ }
+ return 1;
+}
+//by marshmellow - see ASKbiphaseDemod
+int Cmdaskbiphdemod(const char *Cmd)
+{
+ char cmdp = param_getchar(Cmd, 0);
+ if (strlen(Cmd) > 12 || cmdp == 'h' || cmdp == 'H') {
+ PrintAndLog("Usage: data rawdemod ab [offset] [clock] <invert> [maxError] <amplify>");
+ PrintAndLog(" [offset], offset to begin biphase, default=0");
+ PrintAndLog(" [set clock as integer] optional, if not set, autodetect");
+ PrintAndLog(" <invert>, 1 to invert output");
+ PrintAndLog(" [set maximum allowed errors], default = 100");
+ PrintAndLog(" <amplify>, 'a' to attempt demod with ask amplification, default = no amp");
+ PrintAndLog(" NOTE: <invert> can be entered as second or third argument");
+ PrintAndLog(" NOTE: <amplify> can be entered as first, second or last argument");
+ PrintAndLog(" NOTE: any other arg must have previous args set to work");
+ PrintAndLog("");
+ PrintAndLog(" NOTE: --invert for Conditional Dephase Encoding (CDP) AKA Differential Manchester");
+ PrintAndLog("");
+ PrintAndLog(" sample: data rawdemod ab = demod an ask/biph tag from GraphBuffer");
+ PrintAndLog(" : data rawdemod ab a = demod an ask/biph tag from GraphBuffer, amplified");
+ PrintAndLog(" : data rawdemod ab 1 32 = demod an ask/biph tag from GraphBuffer using an offset of 1 and a clock of RF/32");
+ PrintAndLog(" : data rawdemod ab 0 32 1 = demod an ask/biph tag from GraphBuffer using a clock of RF/32 and inverting data");
+ PrintAndLog(" : data rawdemod ab 0 1 = demod an ask/biph tag from GraphBuffer while inverting data");
+ PrintAndLog(" : data rawdemod ab 0 64 1 0 = demod an ask/biph tag from GraphBuffer using a clock of RF/64, inverting data and allowing 0 demod errors");
+ PrintAndLog(" : data rawdemod ab 0 64 1 0 a = demod an ask/biph tag from GraphBuffer using a clock of RF/64, inverting data and allowing 0 demod errors, and amp");
+ return 0;
+ }
+ return ASKbiphaseDemod(Cmd, TRUE);
+}
+
+//by marshmellow
+//attempts to demodulate and identify a G_Prox_II verex/chubb card
+//WARNING: if it fails during some points it will destroy the DemodBuffer data
+// but will leave the GraphBuffer intact.
+//if successful it will push askraw data back to demod buffer ready for emulation
+int CmdG_Prox_II_Demod(const char *Cmd)
+{
+ if (!ASKbiphaseDemod(Cmd, FALSE)){
+ if (g_debugMode) PrintAndLog("ASKbiphaseDemod failed 1st try");
+ return 0;
+ }
+ size_t size = DemodBufferLen;
+ //call lfdemod.c demod for gProxII
+ int ans = gProxII_Demod(DemodBuffer, &size);
+ if (ans < 0){
+ if (g_debugMode) PrintAndLog("Error gProxII_Demod");
+ return 0;
+ }
+ //got a good demod
+ uint32_t ByteStream[65] = {0x00};
+ uint8_t xorKey=0;
+ uint8_t keyCnt=0;
+ uint8_t bitCnt=0;
+ uint8_t ByteCnt=0;
+ size_t startIdx = ans + 6; //start after preamble
+ for (size_t idx = 0; idx<size-6; idx++){
+ if ((idx+1) % 5 == 0){
+ //spacer bit - should be 0
+ if (DemodBuffer[startIdx+idx] != 0) {
+ if (g_debugMode) PrintAndLog("Error spacer not 0: %d, pos: %d",DemodBuffer[startIdx+idx],startIdx+idx);
+ return 0;
+ }
+ continue;
+ }
+ if (keyCnt<8){ //lsb first
+ xorKey = xorKey | (DemodBuffer[startIdx+idx]<<keyCnt);
+ keyCnt++;
+ if (keyCnt==8 && g_debugMode) PrintAndLog("xorKey Found: %02x", xorKey);
+ continue;
+ }
+ //lsb first
+ ByteStream[ByteCnt] = ByteStream[ByteCnt] | (DemodBuffer[startIdx+idx]<<bitCnt);
+ bitCnt++;
+ if (bitCnt % 8 == 0){
+ if (g_debugMode) PrintAndLog("byte %d: %02x",ByteCnt,ByteStream[ByteCnt]);
+ bitCnt=0;
+ ByteCnt++;
+ }
+ }
+ for (uint8_t i = 0; i < ByteCnt; i++){
+ ByteStream[i] ^= xorKey; //xor
+ if (g_debugMode) PrintAndLog("byte %d after xor: %02x", i, ByteStream[i]);
+ }
+ //now ByteStream contains 64 bytes of decrypted raw tag data
+ //
+ uint8_t fmtLen = ByteStream[0]>>2;
+ uint32_t FC = 0;
+ uint32_t Card = 0;
+ uint32_t raw1 = bytebits_to_byte(DemodBuffer+ans,32);
+ uint32_t raw2 = bytebits_to_byte(DemodBuffer+ans+32, 32);
+ uint32_t raw3 = bytebits_to_byte(DemodBuffer+ans+64, 32);
+
+ if (fmtLen==36){
+ FC = ((ByteStream[3] & 0x7F)<<7) | (ByteStream[4]>>1);
+ Card = ((ByteStream[4]&1)<<19) | (ByteStream[5]<<11) | (ByteStream[6]<<3) | (ByteStream[7]>>5);
+ PrintAndLog("G-Prox-II Found: FmtLen %d, FC %d, Card %d",fmtLen,FC,Card);
+ } else if(fmtLen==26){
+ FC = ((ByteStream[3] & 0x7F)<<1) | (ByteStream[4]>>7);
+ Card = ((ByteStream[4]&0x7F)<<9) | (ByteStream[5]<<1) | (ByteStream[6]>>7);
+ PrintAndLog("G-Prox-II Found: FmtLen %d, FC %d, Card %d",fmtLen,FC,Card);
+ } else {
+ PrintAndLog("Unknown G-Prox-II Fmt Found: FmtLen %d",fmtLen);
+ }
+ PrintAndLog("Raw: %08x%08x%08x", raw1,raw2,raw3);
+ setDemodBuf(DemodBuffer+ans, 96, 0);
+ return 1;
+}
+
projects / proxmark3-svn / blobdiff