#include "cmddata.h"
#include "lfdemod.h"
#include "usb_cmd.h"
+#include "crc.h"
uint8_t DemodBuffer[MAX_DEMOD_BUF_LEN];
uint8_t g_debugMode;
int ans = ASKrawDemod(Cmd, FALSE);
if (ans <= 0) {
if (g_debugMode) PrintAndLog("Error AskrawDemod: %d",ans);
- return ans;
+ return 0; //ans;
}
size_t size = DemodBufferLen;
ans = BiphaseRawDecode(DemodBuffer, &size, 0, 0);
if (ans !=0) {
if (g_debugMode) PrintAndLog("Error BiphaseRawDecode: %d",ans);
- return ans;
+ return 0; //ans;
}
//call lfdemod.c demod for gProxII
ans = gProxII_Demod(DemodBuffer, &size);
ans = BiphaseRawDecode(DemodBuffer, &size, 1, 0);
if (ans != 0) {
if (g_debugMode) PrintAndLog("Error BiphaseRawDecode: %d",ans);
- return ans;
+ return 0;//ans;
}
ans = gProxII_Demod(DemodBuffer, &size);
if (ans < 0) {
return ASKrawDemod(Cmd, TRUE);
}
-int CmdAutoCorr(const char *Cmd)
+int AutoCorrelate(int window, bool SaveGrph, bool verbose)
{
static int CorrelBuffer[MAX_GRAPH_TRACE_LEN];
-
- int window = atoi(Cmd);
-
- if (window == 0) {
- PrintAndLog("needs a window");
- return 0;
- }
- if (window >= GraphTraceLen) {
- PrintAndLog("window must be smaller than trace (%d samples)",
- GraphTraceLen);
- return 0;
- }
-
- PrintAndLog("performing %d correlations", GraphTraceLen - window);
-
+ size_t Correlation = 0;
+ int maxSum = 0;
+ int lastMax = 0;
+ if (verbose) PrintAndLog("performing %d correlations", GraphTraceLen - window);
for (int i = 0; i < GraphTraceLen - window; ++i) {
int sum = 0;
for (int j = 0; j < window; ++j) {
sum += (GraphBuffer[j]*GraphBuffer[i + j]) / 256;
}
CorrelBuffer[i] = sum;
+ if (sum >= maxSum-100 && sum <= maxSum+100){
+ //another max
+ Correlation = i-lastMax;
+ lastMax = i;
+ if (sum > maxSum) maxSum = sum;
+ } else if (sum > maxSum){
+ maxSum=sum;
+ lastMax = i;
+ }
+ }
+ if (Correlation==0){
+ //try again with wider margin
+ for (int i = 0; i < GraphTraceLen - window; i++){
+ if (CorrelBuffer[i] >= maxSum-(maxSum*0.05) && CorrelBuffer[i] <= maxSum+(maxSum*0.05)){
+ //another max
+ Correlation = i-lastMax;
+ lastMax = i;
+ //if (CorrelBuffer[i] > maxSum) maxSum = sum;
+ }
+ }
}
- GraphTraceLen = GraphTraceLen - window;
- memcpy(GraphBuffer, CorrelBuffer, GraphTraceLen * sizeof (int));
+ if (verbose && Correlation > 0) PrintAndLog("Possible Correlation: %d samples",Correlation);
- RepaintGraphWindow();
+ if (SaveGrph){
+ GraphTraceLen = GraphTraceLen - window;
+ memcpy(GraphBuffer, CorrelBuffer, GraphTraceLen * sizeof (int));
+ RepaintGraphWindow();
+ }
+ return Correlation;
+}
+
+int usage_data_autocorr(void)
+{
+ //print help
+ PrintAndLog("Usage: data autocorr [window] [g]");
+ PrintAndLog("Options: ");
+ PrintAndLog(" h This help");
+ PrintAndLog(" [window] window length for correlation - default = 4000");
+ PrintAndLog(" g save back to GraphBuffer (overwrite)");
return 0;
}
+int CmdAutoCorr(const char *Cmd)
+{
+ char cmdp = param_getchar(Cmd, 0);
+ if (cmdp == 'h' || cmdp == 'H')
+ return usage_data_autocorr();
+ int window = 4000; //set default
+ char grph=0;
+ bool updateGrph = FALSE;
+ sscanf(Cmd, "%i %c", &window, &grph);
+
+ if (window >= GraphTraceLen) {
+ PrintAndLog("window must be smaller than trace (%d samples)",
+ GraphTraceLen);
+ return 0;
+ }
+ if (grph == 'g') updateGrph=TRUE;
+ return AutoCorrelate(window, updateGrph, TRUE);
+}
+
int CmdBitsamples(const char *Cmd)
{
int cnt = 0;
// w = wiegand parity, x = extra space for other formats
// p = unknown checksum
// (26 bit format shown)
-
+
+ //get bytes for checksum calc
+ uint8_t checksum = bytebits_to_byte(BitStream + idx + 120, 8);
+ uint8_t csBuff[14] = {0x00};
+ for (uint8_t i = 0; i < 13; i++){
+ csBuff[i] = bytebits_to_byte(BitStream + idx + 16 + (i*8), 8);
+ }
+ //check checksum calc
+ //checksum calc thanks to ICEMAN!!
+ uint32_t checkCS = CRC8Maxim(csBuff,13);
+
//get raw ID before removing parities
uint32_t rawLo = bytebits_to_byte(BitStream+idx+96,32);
uint32_t rawHi = bytebits_to_byte(BitStream+idx+64,32);
size = removeParity(BitStream, idx+8, 8, 1, 120);
if (size != 105){
- if (g_debugMode==1) PrintAndLog("DEBUG: Error at parity check-tag size does not match Pyramid format, SIZE: %d, IDX: %d, hi3: %x",size, idx, rawHi3);
+ if (g_debugMode==1)
+ PrintAndLog("DEBUG: Error at parity check - tag size does not match Pyramid format, SIZE: %d, IDX: %d, hi3: %x",size, idx, rawHi3);
return 0;
}
PrintAndLog("Pyramid ID Found - BitLength: %d -unknown BitLength- (%d), Raw: %08x%08x%08x%08x", fmtLen, cardnum, rawHi3, rawHi2, rawHi, rawLo);
}
}
+ if (checksum == checkCS)
+ PrintAndLog("Checksum %02x passed", checksum);
+ else
+ PrintAndLog("Checksum %02x failed - should have been %02x", checksum, checkCS);
+
if (g_debugMode){
PrintAndLog("DEBUG: idx: %d, Len: %d, Printing Demod Buffer:", idx, 128);
printDemodBuff();
{"askgproxiidemod",CmdG_Prox_II_Demod,1, "Demodulate a G Prox II tag from GraphBuffer"},
//{"askmandemod", Cmdaskmandemod, 1, "[clock] [invert<0|1>] [maxErr] -- Attempt to demodulate ASK/Manchester tags and output binary (args optional)"},
//{"askrawdemod", Cmdaskrawdemod, 1, "[clock] [invert<0|1>] -- Attempt to demodulate ASK tags and output bin (args optional)"},
- {"autocorr", CmdAutoCorr, 1, "<window length> -- Autocorrelation over window"},
+ {"autocorr", CmdAutoCorr, 1, "[window length] [g] -- Autocorrelation over window - g to save back to GraphBuffer (overwrite)"},
{"biphaserawdecode",CmdBiphaseDecodeRaw,1,"[offset] [invert<0|1>] Biphase decode bin stream in DemodBuffer (offset = 0|1 bits to shift the decode start)"},
{"bitsamples", CmdBitsamples, 0, "Get raw samples as bitstring"},
//{"bitstream", CmdBitstream, 1, "[clock rate] -- Convert waveform into a bitstream"},