X-Git-Url: http://git.zerfleddert.de/cgi-bin/gitweb.cgi/proxmark3-svn/blobdiff_plain/2147c307785639944f4843d7cf0d245778532ecf..13d77ef964cefe68750873d5268299a53c9e22a5:/common/lfdemod.c diff --git a/common/lfdemod.c b/common/lfdemod.c index 46ac4924..5b0bc29d 100644 --- a/common/lfdemod.c +++ b/common/lfdemod.c @@ -75,51 +75,6 @@ uint8_t preambleSearch(uint8_t *BitStream, uint8_t *preamble, size_t pLen, size_ return 0; } - -//by marshmellow -//takes 1s and 0s and searches for EM410x format - output EM ID -uint64_t Em410xDecodeOld(uint8_t *BitStream, size_t *size, size_t *startIdx) -{ - //no arguments needed - built this way in case we want this to be a direct call from "data " cmds in the future - // otherwise could be a void with no arguments - //set defaults - uint64_t lo=0; - uint32_t i = 0; - if (BitStream[1]>1){ //allow only 1s and 0s - // PrintAndLog("no data found"); - return 0; - } - // 111111111 bit pattern represent start of frame - uint8_t preamble[] = {1,1,1,1,1,1,1,1,1}; - uint32_t idx = 0; - uint32_t parityBits = 0; - uint8_t errChk = 0; - *startIdx = 0; - for (uint8_t extraBitChk=0; extraBitChk<5; extraBitChk++){ - errChk = preambleSearch(BitStream+extraBitChk+*startIdx, preamble, sizeof(preamble), size, startIdx); - if (errChk == 0) return 0; - idx = *startIdx + 9; - for (i=0; i<10;i++){ //loop through 10 sets of 5 bits (50-10p = 40 bits) - parityBits = bytebits_to_byte(BitStream+(i*5)+idx,5); - //check even parity - if (parityTest(parityBits, 5, 0) == 0){ - //parity failed try next bit (in the case of 1111111111) but last 9 = preamble - startIdx++; - errChk = 0; - break; - } - //set uint64 with ID from BitStream - for (uint8_t ii=0; ii<4; ii++){ - lo = (lo << 1LL) | (BitStream[(i*5)+ii+idx]); - } - } - if (errChk != 0) return lo; - //skip last 5 bit parity test for simplicity. - // *size = 64; - } - return 0; -} - //by marshmellow //takes 1s and 0s and searches for EM410x format - output EM ID uint8_t Em410xDecode(uint8_t *BitStream, size_t *size, size_t *startIdx, uint32_t *hi, uint64_t *lo) @@ -143,6 +98,7 @@ uint8_t Em410xDecode(uint8_t *BitStream, size_t *size, size_t *startIdx, uint32_ errChk = preambleSearch(BitStream+extraBitChk+*startIdx, preamble, sizeof(preamble), size, startIdx); if (errChk == 0) return 0; if (*size>64) FmtLen = 22; + if (*size<64) return 0; idx = *startIdx + 9; for (i=0; i= high && waveHigh){ + smplCnt++; + } else if (BinStream[i] <= low && !waveHigh){ + smplCnt++; + } else { //not high or low or a transition + if (smplCnt > clk-(clk/4)) { //full clock + if (smplCnt > clk + (clk/4)) { //too many samples + errCnt++; + BinStream[bitCnt++]=77; + } else if (waveHigh) { + BinStream[bitCnt++] = invert; + BinStream[bitCnt++] = invert; + } else if (!waveHigh) { + BinStream[bitCnt++] = invert ^ 1; + BinStream[bitCnt++] = invert ^ 1; + } + waveHigh ^= 1; + smplCnt = 0; + } else if (smplCnt > (clk/2) - (clk/5)) { + if (waveHigh) { + BinStream[bitCnt++] = invert; + } else if (!waveHigh) { + BinStream[bitCnt++] = invert ^ 1; + } + waveHigh ^= 1; + smplCnt = 0; + } else if (!bitCnt) { + //first bit + waveHigh = (BinStream[i] >= high); + smplCnt = 1; + } else { + //transition bit? ignore + } + } + } + *size = bitCnt; + return errCnt; +} + //by marshmellow //takes 3 arguments - clock, invert and maxErr as integers //attempts to demodulate ask only @@ -423,15 +421,22 @@ int askrawdemod(uint8_t *BinStream, size_t *size, int *clk, int *invert, int max if (*clk==0) return -1; if (start<0) return -1; if (*invert != 0 && *invert != 1) *invert =0; + if (amp==1) askAmp(BinStream, *size); + uint32_t initLoopMax = 200; if (initLoopMax > *size) initLoopMax=*size; // Detect high and lows - //25% fuzz in case highs and lows aren't clipped [marshmellow] + //25% clip in case highs and lows aren't clipped [marshmellow] + uint8_t clip = 75; int high, low, ans; - if (amp==1) askAmp(BinStream, *size); - ans = getHiLo(BinStream, initLoopMax, &high, &low, 75, 75); + ans = getHiLo(BinStream, initLoopMax, &high, &low, clip, clip); if (ans<1) return -1; //just noise + if (DetectCleanAskWave(BinStream, *size, high, low)) { + //PrintAndLog("Clean"); + return cleanAskRawDemod(BinStream, size, *clk, *invert, high, low); + } + //PrintAndLog("DEBUG - valid high: %d - valid low: %d",high,low); int lastBit = 0; //set first clock check uint32_t bitnum = 0; //output counter @@ -443,12 +448,13 @@ int askrawdemod(uint8_t *BinStream, size_t *size, int *clk, int *invert, int max uint32_t gLen = *size; if (gLen > 500) gLen=500; //if 0 errors allowed then only try first 2 clock cycles as we want a low tolerance - if (!maxErr) gLen=*clk*2; + if (!maxErr) gLen = *clk * 2; uint8_t errCnt =0; uint32_t bestStart = *size; uint32_t bestErrCnt = maxErr; //(*size/1000); uint8_t midBit=0; uint16_t MaxBits=1000; + //PrintAndLog("DEBUG - lastbit - %d",lastBit); //loop to find first wave that works for (iii=start; iii < gLen; ++iii){ @@ -619,7 +625,9 @@ size_t fsk_wave_demod(uint8_t * dest, size_t size, uint8_t fchigh, uint8_t fclow //do nothing with extra garbage } else if ((idx-last_transition) < (fchigh-1)) { //6-8 = 8 waves dest[numBits]=1; - } else { //9+ = 10 waves + } else if ((idx-last_transition) > (fchigh+1) && !numBits) { //12 + and first bit = garbage + //do nothing with beginning garbage + } else { //9+ = 10 waves dest[numBits]=0; } last_transition = idx; @@ -643,18 +651,31 @@ size_t aggregate_bits(uint8_t *dest, size_t size, uint8_t rfLen, uint8_t maxCons uint32_t idx=0; size_t numBits=0; uint32_t n=1; - + float lowWaves = (((float)(rfLen))/((float)fclow)); + float highWaves = (((float)(rfLen))/((float)fchigh)); for( idx=1; idx < size; idx++) { if (dest[idx]==lastval) { n++; continue; } + n++; //if lastval was 1, we have a 1->0 crossing - if ( dest[idx-1]==1 ) { - n=myround2((float)(n+1)/((float)(rfLen)/(float)fclow)); - } else {// 0->1 crossing - n=myround2((float)(n+1)/((float)(rfLen-1)/(float)fchigh)); //-1 for fudge factor + if (dest[idx-1]==1) { + if (!numBits && n < (uint8_t)lowWaves) { + n=0; + lastval = dest[idx]; + continue; + } + n=myround2(((float)n)/lowWaves); + } else {// 0->1 crossing + //test first bitsample too small + if (!numBits && n < (uint8_t)highWaves) { + n=0; + lastval = dest[idx]; + continue; + } + n = myround2(((float)n)/highWaves); //-1 for fudge factor } if (n == 0) n = 1; @@ -670,6 +691,17 @@ size_t aggregate_bits(uint8_t *dest, size_t size, uint8_t rfLen, uint8_t maxCons n=0; lastval=dest[idx]; }//end for + + // if valid extra bits at the end were all the same frequency - add them in + if (n > lowWaves && n > highWaves) { + if (dest[idx-2]==1) { + n=myround2((float)(n+1)/((float)(rfLen)/(float)fclow)); + } else { + n=myround2((float)(n+1)/((float)(rfLen-1)/(float)fchigh)); //-1 for fudge factor + } + memset(dest, dest[idx-1]^invert , n); + numBits += n; + } return numBits; } //by marshmellow (from holiman's base) @@ -858,18 +890,64 @@ uint8_t DetectCleanAskWave(uint8_t dest[], size_t size, int high, int low) { uint8_t allPeaks=1; uint16_t cntPeaks=0; - for (size_t i=20; i<255; i++){ + for (size_t i=30; i<255; i++){ if (dest[i]>low && dest[i]190) return 1; + if (cntPeaks>210) return 1; } return allPeaks; } +int DetectStrongAskClock(uint8_t dest[], size_t size) +{ + int clk[]={0,8,16,32,40,50,64,100,128,256}; + size_t idx = 40; + uint8_t high=0; + size_t cnt = 0; + size_t highCnt = 0; + size_t highCnt2 = 0; + for (;idx < size; idx++){ + if (dest[idx]>128) { + if (!high){ + high=1; + if (cnt > highCnt){ + if (highCnt != 0) highCnt2 = highCnt; + highCnt = cnt; + } else if (cnt > highCnt2) { + highCnt2 = cnt; + } + cnt=1; + } else { + cnt++; + } + } else if (dest[idx] <= 128){ + if (high) { + high=0; + if (cnt > highCnt) { + if (highCnt != 0) highCnt2 = highCnt; + highCnt = cnt; + } else if (cnt > highCnt2) { + highCnt2 = cnt; + } + cnt=1; + } else { + cnt++; + } + } + } + for (idx=8; idx>0; idx--){ + if (clk[idx] >= highCnt && clk[idx] <= highCnt+2) + return clk[idx]; + if (clk[idx] >= highCnt2 && clk[idx] <= highCnt2+2) + return clk[idx]; + } + return -1; +} + // by marshmellow // not perfect especially with lower clocks or VERY good antennas (heavy wave clipping) // maybe somehow adjust peak trimming value based on samples to fix? @@ -892,24 +970,14 @@ int DetectASKClock(uint8_t dest[], size_t size, int *clock, int maxErr) //test for large clean peaks if (DetectCleanAskWave(dest, size, peak, low)==1){ - uint16_t fcTest=0; - uint8_t mostFC=0; - fcTest=countFC(dest, size, &mostFC); - uint8_t fc1 = fcTest >> 8; - uint8_t fc2 = fcTest & 0xFF; - - for (i=0; i<8; i++){ - if (clk[i] == fc1) { - *clock=fc1; - return 0; - } - if (clk[i] == fc2) { - *clock=fc2; + int ans = DetectStrongAskClock(dest, size); + for (i=7; i>0; i--){ + if (clk[i] == ans) { + *clock=ans; return 0; } } } - int ii; int clkCnt; int tol = 0; @@ -923,6 +991,7 @@ int DetectASKClock(uint8_t dest[], size_t size, int *clock, int maxErr) }else{ tol=0; } + if (!maxErr) loopCnt=clk[clkCnt]*2; bestErr[clkCnt]=1000; //try lining up the peaks by moving starting point (try first 256) for (ii=0; ii < loopCnt; ii++){ @@ -1242,11 +1311,10 @@ int nrzRawDemod(uint8_t *dest, size_t *size, int *clk, int *invert, int maxErr) *clk = DetectNRZClock(dest, *size, *clk); if (*clk==0) return -2; uint32_t i; - int high, low, ans; - ans = getHiLo(dest, 1260, &high, &low, 75, 75); //25% fuzz on high 25% fuzz on low - if (ans<1) return -2; //just noise - uint32_t gLen = 256; + uint32_t gLen = 4096; if (gLen>*size) gLen = *size; + int high, low; + if (getHiLo(dest, gLen, &high, &low, 75, 75) < 1) return -3; //25% fuzz on high 25% fuzz on low int lastBit = 0; //set first clock check uint32_t bitnum = 0; //output counter uint8_t tol = 1; //clock tolerance adjust - waves will be accepted as within the clock if they fall + or - this value + clock from last valid wave @@ -1256,6 +1324,8 @@ int nrzRawDemod(uint8_t *dest, size_t *size, int *clk, int *invert, int maxErr) uint32_t bestErrCnt = maxErr+1; uint32_t bestPeakCnt = 0; uint32_t bestPeakStart=0; + uint8_t bestFirstPeakHigh=0; + uint8_t firstPeakHigh=0; uint8_t curBit=0; uint8_t bitHigh=0; uint8_t errBitHigh=0; @@ -1265,6 +1335,8 @@ int nrzRawDemod(uint8_t *dest, size_t *size, int *clk, int *invert, int maxErr) //loop to find first wave that works - align to clock for (iii=0; iii < gLen; ++iii){ if ((dest[iii]>=high) || (dest[iii]<=low)){ + if (dest[iii]>=high) firstPeakHigh=1; + else firstPeakHigh=0; lastBit=iii-*clk; peakCnt=0; errCnt=0; @@ -1315,6 +1387,7 @@ int nrzRawDemod(uint8_t *dest, size_t *size, int *clk, int *invert, int maxErr) //possible good read if (errCnt == 0){ //bestStart = iii; + bestFirstPeakHigh=firstPeakHigh; bestErrCnt = errCnt; bestPeakCnt = peakCnt; bestPeakStart = iii; @@ -1325,6 +1398,7 @@ int nrzRawDemod(uint8_t *dest, size_t *size, int *clk, int *invert, int maxErr) //bestStart = iii; } if (peakCnt > bestPeakCnt){ + bestFirstPeakHigh=firstPeakHigh; bestPeakCnt=peakCnt; bestPeakStart=iii; } @@ -1337,6 +1411,8 @@ int nrzRawDemod(uint8_t *dest, size_t *size, int *clk, int *invert, int maxErr) iii=bestPeakStart; lastBit=bestPeakStart-*clk; bitnum=0; + memset(dest, bestFirstPeakHigh^1, bestPeakStart / *clk); + bitnum += (bestPeakStart / *clk); for (i = iii; i < *size; ++i) { //if we found a high bar and we are at a clock bit if ((dest[i] >= high ) && (i>=lastBit+*clk-tol && i<=lastBit+*clk+tol)){ @@ -1386,12 +1462,12 @@ int nrzRawDemod(uint8_t *dest, size_t *size, int *clk, int *invert, int maxErr) *size=bitnum; } else{ *size=bitnum; - return -1; + return bestErrCnt; } if (bitnum>16){ *size=bitnum; - } else return -1; + } else return -5; return errCnt; } @@ -1689,7 +1765,7 @@ int pskRawDemod(uint8_t dest[], size_t *size, int *clock, int *invert) errCnt=0; size_t numBits=0; //set skipped bits - memset(dest+numBits,curPhase^1,firstFullWave / *clock); + memset(dest,curPhase^1,firstFullWave / *clock); numBits += (firstFullWave / *clock); dest[numBits++] = curPhase; //set first read bit for (i = firstFullWave+fullWaveLen-1; i < *size-3; i++){