X-Git-Url: http://git.zerfleddert.de/cgi-bin/gitweb.cgi/proxmark3-svn/blobdiff_plain/7a8a982bde66f752d8aa28423d70487d04f7572c..327a690813ff04d580a2630977f160b8ec809bd9:/common/lfdemod.c diff --git a/common/lfdemod.c b/common/lfdemod.c index 0a81c6b8..92ad633e 100644 --- a/common/lfdemod.c +++ b/common/lfdemod.c @@ -55,7 +55,7 @@ uint8_t parityTest(uint32_t bits, uint8_t bitLen, uint8_t pType) } //by marshmellow -//search for given preamble in given BitStream and return startIndex and length +//search for given preamble in given BitStream and return success=1 or fail=0 and startIndex and length uint8_t preambleSearch(uint8_t *BitStream, uint8_t *preamble, size_t pLen, size_t *size, size_t *startIdx) { uint8_t foundCnt=0; @@ -75,48 +75,47 @@ 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 Em410xDecode(uint8_t *BitStream, size_t *size, size_t *startIdx) +uint8_t Em410xDecode(uint8_t *BitStream, size_t *size, size_t *startIdx, uint32_t *hi, uint64_t *lo) { //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}; + // include 0 in front to help get start pos + uint8_t preamble[] = {0,1,1,1,1,1,1,1,1,1}; uint32_t idx = 0; uint32_t parityBits = 0; uint8_t errChk = 0; + uint8_t FmtLen = 10; *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]); - } + errChk = preambleSearch(BitStream, preamble, sizeof(preamble), size, startIdx); + if (errChk == 0 || *size < 64) return 0; + if (*size > 64) FmtLen = 22; + *startIdx += 1; //get rid of 0 from preamble + idx = *startIdx + 9; + for (i=0; i> 63); + *lo = (*lo << 1) | (BitStream[(i*5)+ii+idx]); } - if (errChk != 0) return lo; - //skip last 5 bit parity test for simplicity. - // *size = 64; } + if (errChk != 0) return 1; + //skip last 5 bit parity test for simplicity. + // *size = 64 | 128; return 0; } @@ -151,6 +150,8 @@ int askmandemod(uint8_t *BinStream, size_t *size, int *clk, int *invert, int max int iii = 0; uint32_t gLen = *size; if (gLen > 3000) gLen=3000; + //if 0 errors allowed then only try first 2 clock cycles as we want a low tolerance + if (!maxErr) gLen=*clk*2; uint8_t errCnt =0; uint16_t MaxBits = 500; uint32_t bestStart = *size; @@ -260,16 +261,12 @@ int ManchesterEncode(uint8_t *BitStream, size_t size) //run through 2 times and take least errCnt int manrawdecode(uint8_t * BitStream, size_t *size) { - uint16_t bitnum=0; - uint16_t MaxBits = 500; - uint16_t errCnt = 0; - size_t i=1; - uint16_t bestErr = 1000; - uint16_t bestRun = 0; - size_t ii=1; + uint16_t bitnum=0, MaxBits = 512, errCnt = 0; + size_t i, ii; + uint16_t bestErr = 1000, bestRun = 0; if (size == 0) return -1; - for (ii=1;ii<3;++ii){ - i=1; + for (ii=0;ii<2;++ii){ + i=0; for (i=i+ii;i<*size-2;i+=2){ if(BitStream[i]==1 && (BitStream[i+1]==0)){ } else if((BitStream[i]==0)&& BitStream[i+1]==1){ @@ -287,7 +284,7 @@ int manrawdecode(uint8_t * BitStream, size_t *size) errCnt=bestErr; if (errCnt<20){ ii=bestRun; - i=1; + i=0; for (i=i+ii; i < *size-2; i+=2){ if(BitStream[i] == 1 && (BitStream[i+1] == 0)){ BitStream[bitnum++]=0; @@ -305,16 +302,30 @@ int manrawdecode(uint8_t * BitStream, size_t *size) } //by marshmellow -//take 01 or 10 = 0 and 11 or 00 = 1 +//take 01 or 10 = 1 and 11 or 00 = 0 +//check for phase errors - should never have 111 or 000 should be 01001011 or 10110100 for 1010 +//decodes biphase or if inverted it is AKA conditional dephase encoding AKA differential manchester encoding int BiphaseRawDecode(uint8_t *BitStream, size_t *size, int offset, int invert) { uint16_t bitnum=0; uint32_t errCnt =0; - uint32_t i; - uint16_t MaxBits=500; - i=offset; - if (size == 0) return -1; - for (;i<*size-2; i+=2){ + size_t i=offset; + uint16_t MaxBits=512; + //if not enough samples - error + if (*size < 51) return -1; + //check for phase change faults - skip one sample if faulty + uint8_t offsetA = 1, offsetB = 1; + for (; i<48; i+=2){ + if (BitStream[i+1]==BitStream[i+2]) offsetA=0; + if (BitStream[i+2]==BitStream[i+3]) offsetB=0; + } + if (!offsetA && offsetB) offset++; + for (i=offset; i<*size-3; i+=2){ + //check for phase error + if (BitStream[i+1]==BitStream[i+2]) { + BitStream[bitnum++]=77; + errCnt++; + } if((BitStream[i]==1 && BitStream[i+1]==0) || (BitStream[i]==0 && BitStream[i+1]==1)){ BitStream[bitnum++]=1^invert; } else if((BitStream[i]==0 && BitStream[i+1]==0) || (BitStream[i]==1 && BitStream[i+1]==1)){ @@ -351,6 +362,56 @@ void askAmp(uint8_t *BitStream, size_t size) return; } +int cleanAskRawDemod(uint8_t *BinStream, size_t *size, int clk, int invert, int high, int low) +{ + size_t bitCnt=0, smplCnt=0, errCnt=0; + uint8_t waveHigh = 0; + //PrintAndLog("clk: %d", clk); + for (size_t i=0; i < *size; i++){ + if (BinStream[i] >= high && waveHigh){ + smplCnt++; + } else if (BinStream[i] <= low && !waveHigh){ + smplCnt++; + } else { //transition + if ((BinStream[i] >= high && !waveHigh) || (BinStream[i] <= low && waveHigh)){ + if (smplCnt > clk-(clk/4)-1) { //full clock + if (smplCnt > clk + (clk/4)+1) { //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/4)-1) { + 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 { + smplCnt++; + //transition bit oops + } + } else { //haven't hit new high or new low yet + smplCnt++; + } + } + } + *size = bitCnt; + return errCnt; +} + //by marshmellow //takes 3 arguments - clock, invert and maxErr as integers //attempts to demodulate ask only @@ -362,15 +423,22 @@ 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 @@ -381,11 +449,14 @@ int askrawdemod(uint8_t *BinStream, size_t *size, int *clk, int *invert, int max uint32_t iii = 0; 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; 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){ @@ -556,7 +627,9 @@ 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; @@ -580,18 +653,31 @@ 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; @@ -607,6 +693,17 @@ 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) @@ -793,20 +890,70 @@ int PyramiddemodFSK(uint8_t *dest, size_t *size) uint8_t DetectCleanAskWave(uint8_t dest[], size_t size, int high, int low) { - uint8_t allPeaks=1; + uint16_t allPeaks=1; uint16_t cntPeaks=0; - for (size_t i=20; i<255; i++){ + size_t loopEnd = 572; + if (loopEnd > size) loopEnd = size; + for (size_t i=60; ilow && dest[i]190) return 1; + if (allPeaks == 0){ + if (cntPeaks > 300) 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++; + } + } + } + uint8_t tol; + for (idx=8; idx>0; idx--){ + tol = clk[idx]/8; + if (clk[idx] >= highCnt - tol && clk[idx] <= highCnt + tol) + return clk[idx]; + if (clk[idx] >= highCnt2 - tol && clk[idx] <= highCnt2 + tol) + 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? @@ -829,24 +976,14 @@ 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; @@ -860,6 +997,7 @@ 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++){ @@ -1179,11 +1317,10 @@ 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 @@ -1193,6 +1330,8 @@ 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; @@ -1202,6 +1341,8 @@ 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; @@ -1252,6 +1393,7 @@ 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; @@ -1262,6 +1404,7 @@ 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; } @@ -1274,6 +1417,8 @@ 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)){ @@ -1323,12 +1468,12 @@ 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; } @@ -1626,7 +1771,7 @@ 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++){