From 73d04bb417f52be89450e851deebcbd6ae125952 Mon Sep 17 00:00:00 2001 From: marshmellow42 Date: Fri, 13 Mar 2015 11:09:12 -0400 Subject: [PATCH] data psk demod minor fixes, pyramid demod add CS also adjusted autocorrelate and added a printout for lf search u --- client/cmddata.c | 80 ++++++++++++++++++++++++++++++--------- client/cmddata.h | 1 + client/cmdlf.c | 4 +- common/crc.c | 15 +++++++- {include => common}/crc.h | 3 ++ common/lfdemod.c | 51 ++++++++++--------------- 6 files changed, 104 insertions(+), 50 deletions(-) rename {include => common}/crc.h (94%) diff --git a/client/cmddata.c b/client/cmddata.c index 95c7dc87..6d85cf68 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; @@ -729,10 +730,52 @@ 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]; + 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; + } + } + } + if (verbose && Correlation > 0) PrintAndLog("Possible Correlation: %d samples",Correlation); + if (SaveGrph){ + GraphTraceLen = GraphTraceLen - window; + memcpy(GraphBuffer, CorrelBuffer, GraphTraceLen * sizeof (int)); + RepaintGraphWindow(); + } + return Correlation; +} + +int CmdAutoCorr(const char *Cmd) +{ int window = atoi(Cmd); if (window == 0) { @@ -744,21 +787,7 @@ int CmdAutoCorr(const char *Cmd) GraphTraceLen); return 0; } - - 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; - } - GraphTraceLen = GraphTraceLen - window; - memcpy(GraphBuffer, CorrelBuffer, GraphTraceLen * sizeof (int)); - - RepaintGraphWindow(); - return 0; + return AutoCorrelate(window, TRUE, TRUE); } int CmdBitsamples(const char *Cmd) @@ -1434,7 +1463,16 @@ 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 + int 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 +1482,8 @@ 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 +1541,11 @@ 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(); diff --git a/client/cmddata.h b/client/cmddata.h index 6866bcb1..80fa5a9b 100644 --- a/client/cmddata.h +++ b/client/cmddata.h @@ -23,6 +23,7 @@ int CmdAskEM410xDemod(const char *Cmd); int CmdG_Prox_II_Demod(const char *Cmd); int Cmdaskrawdemod(const char *Cmd); int Cmdaskmandemod(const char *Cmd); +int AutoCorrelate(int window, bool SaveGrph, bool verbose); int CmdAutoCorr(const char *Cmd); int CmdBiphaseDecodeRaw(const char *Cmd); int CmdBitsamples(const char *Cmd); diff --git a/client/cmdlf.c b/client/cmdlf.c index 79d6787b..dddf3dee 100644 --- a/client/cmdlf.c +++ b/client/cmdlf.c @@ -1080,7 +1080,9 @@ int CmdLFfind(const char *Cmd) if (testRaw=='u' || testRaw=='U'){ //test unknown tag formats (raw mode) PrintAndLog("\nChecking for Unknown tags:\n"); - ans=CmdDetectClockRate("f"); + ans=AutoCorrelate(4000, FALSE, FALSE); + if (ans > 0) PrintAndLog("Possible Auto Correlation of %d repeating samples",ans); + ans=CmdDetectClockRate("F"); //GetFSKClock("",TRUE,FALSE); if (ans != 0){ //fsk ans=CmdFSKrawdemod(""); if (ans>0) { diff --git a/common/crc.c b/common/crc.c index 90d57afa..b8eb227e 100644 --- a/common/crc.c +++ b/common/crc.c @@ -5,8 +5,9 @@ //----------------------------------------------------------------------------- // Generic CRC calculation code. //----------------------------------------------------------------------------- - #include "crc.h" +#include +#include void crc_init(crc_t *crc, int order, uint32_t polynom, uint32_t initial_value, uint32_t final_xor) { @@ -40,3 +41,15 @@ uint32_t crc_finish(crc_t *crc) { return ( crc->state ^ crc->final_xor ) & crc->mask; } + +uint32_t CRC8Maxim(uint8_t *buff, size_t size ) +{ + crc_t crc; + crc_init(&crc, 9, 0x8c, 0x00, 0x00); + crc_clear(&crc); + + for (size_t i=0; i < size; ++i){ + crc_update(&crc, buff[i], 8); + } + return crc_finish(&crc); +} diff --git a/include/crc.h b/common/crc.h similarity index 94% rename from include/crc.h rename to common/crc.h index 8e68f3b3..adbfb237 100644 --- a/include/crc.h +++ b/common/crc.h @@ -10,6 +10,7 @@ #define __CRC_H #include +#include typedef struct crc { uint32_t state; @@ -36,6 +37,8 @@ extern void crc_clear(crc_t *crc); /* Get the result of the crc calculation */ extern uint32_t crc_finish(crc_t *crc); +// Calculate CRC-8/Maxim checksum +uint32_t CRC8Maxim(uint8_t *buff, size_t size ); /* Static initialization of a crc structure */ #define CRC_INITIALIZER(_order, _polynom, _initial_value, _final_xor) { \ .state = ((_initial_value) & ((1L<<(_order))-1)), \ diff --git a/common/lfdemod.c b/common/lfdemod.c index a42566ad..db945d0a 100644 --- a/common/lfdemod.c +++ b/common/lfdemod.c @@ -1589,7 +1589,7 @@ int pskRawDemod(uint8_t dest[], size_t *size, int *clock, int *invert) if (*size= dest[i+2]){ - if (waveStart == 0) { - waveStart = i+1; - avgWaveVal=dest[i+1]; - //PrintAndLog("DEBUG: waveStart: %d",waveStart); - } else { - waveEnd = i+1; - //PrintAndLog("DEBUG: waveEnd: %d",waveEnd); - waveLenCnt = waveEnd-waveStart; - lastAvgWaveVal = avgWaveVal/waveLenCnt; - if (waveLenCnt > fc){ - firstFullWave = waveStart; - fullWaveLen=waveLenCnt; - //if average wave value is > graph 0 then it is an up wave or a 1 - if (lastAvgWaveVal > 128) curPhase^=1; - break; - } - waveStart=0; - avgWaveVal=0; - } + waveEnd = i+1; + //PrintAndLog("DEBUG: waveEnd: %d",waveEnd); + waveLenCnt = waveEnd-waveStart; + if (waveLenCnt > fc && waveStart > fc){ //not first peak and is a large wave + lastAvgWaveVal = avgWaveVal/(waveLenCnt); + firstFullWave = waveStart; + fullWaveLen=waveLenCnt; + //if average wave value is > graph 0 then it is an up wave or a 1 + if (lastAvgWaveVal > 123) curPhase^=1; //fudge graph 0 a little 123 vs 128 + break; + } + waveStart = i+1; + avgWaveVal = 0; } - avgWaveVal+=dest[i+1]; + avgWaveVal+=dest[i+2]; } //PrintAndLog("DEBUG: firstFullWave: %d, waveLen: %d",firstFullWave,fullWaveLen); lastClkBit = firstFullWave; //set start of wave as clock align @@ -1629,7 +1623,7 @@ int pskRawDemod(uint8_t dest[], size_t *size, int *clock, int *invert) errCnt=0; size_t numBits=0; //PrintAndLog("DEBUG: clk: %d, lastClkBit: %d", *clock, lastClkBit); - + dest[numBits++] = curPhase; //set first read bit for (i = firstFullWave+fullWaveLen-1; i < *size-3; i++){ //top edge of wave = start of new wave if (dest[i]+fc < dest[i+1] && dest[i+1] >= dest[i+2]){ @@ -1641,26 +1635,23 @@ int pskRawDemod(uint8_t dest[], size_t *size, int *clock, int *invert) waveEnd = i+1; waveLenCnt = waveEnd-waveStart; lastAvgWaveVal = avgWaveVal/waveLenCnt; - if (waveLenCnt > fc){ + if (waveLenCnt > fc){ //PrintAndLog("DEBUG: avgWaveVal: %d, waveSum: %d",lastAvgWaveVal,avgWaveVal); //if this wave is a phase shift //PrintAndLog("DEBUG: phase shift at: %d, len: %d, nextClk: %d, i: %d, fc: %d",waveStart,waveLenCnt,lastClkBit+*clock-tol,i+1,fc); if (i+1 >= lastClkBit + *clock - tol){ //should be a clock bit curPhase^=1; - dest[numBits] = curPhase; - numBits++; + dest[numBits++] = curPhase; lastClkBit += *clock; - } else if (i lastClkBit + *clock + tol + fc){ lastClkBit += *clock; //no phase shift but clock bit - dest[numBits] = curPhase; - numBits++; + dest[numBits++] = curPhase; } avgWaveVal=0; waveStart=i+1; -- 2.39.2