X-Git-Url: http://git.zerfleddert.de/cgi-bin/gitweb.cgi/proxmark3-svn/blobdiff_plain/13024283676d477113b2a9d5a5ccf71c50bc7bbe..9f7bbd24c9eabeed1cb92376750a549f9476f3ad:/client/cmddata.c

diff --git a/client/cmddata.c b/client/cmddata.c
index 95c7dc87..d5b072c0 100644
--- a/client/cmddata.c
+++ b/client/cmddata.c
@@ -22,6 +22,7 @@
 #include "cmddata.h"
 #include "lfdemod.h"
 #include "usb_cmd.h"
+#include "crc.h"
 
 uint8_t DemodBuffer[MAX_DEMOD_BUF_LEN];
 uint8_t g_debugMode;
@@ -622,13 +623,13 @@ int CmdG_Prox_II_Demod(const char *Cmd)
   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);
@@ -638,7 +639,7 @@ int CmdG_Prox_II_Demod(const char *Cmd)
     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) {
@@ -729,38 +730,80 @@ int Cmdaskrawdemod(const char *Cmd)
   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;
@@ -1434,7 +1477,16 @@ int CmdFSKdemodPyramid(const char *Cmd)
   // 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
+  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);
@@ -1444,7 +1496,8 @@ int CmdFSKdemodPyramid(const char *Cmd)
 
   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;
   }
 
@@ -1502,6 +1555,11 @@ int CmdFSKdemodPyramid(const char *Cmd)
       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();
@@ -2581,7 +2639,7 @@ static command_t CommandTable[] =
   {"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"},