X-Git-Url: https://git.zerfleddert.de/cgi-bin/gitweb.cgi/proxmark3-svn/blobdiff_plain/2df8c07907a07068d717d9b4ddcc2848f4efd608..0c5998c0518144270e9c85c2771bf29ddd906384:/common/lfdemod.c diff --git a/common/lfdemod.c b/common/lfdemod.c index 1c3aad6f..88a250d8 100644 --- a/common/lfdemod.c +++ b/common/lfdemod.c @@ -1,439 +1,496 @@ //----------------------------------------------------------------------------- -// Copyright (C) 2014 +// Copyright (C) 2014 // // This code is licensed to you under the terms of the GNU GPL, version 2 or, // at your option, any later version. See the LICENSE.txt file for the text of // the license. //----------------------------------------------------------------------------- -// Low frequency commands +// Low frequency demod/decode commands //----------------------------------------------------------------------------- -//#include #include #include -//#include -//#include #include "lfdemod.h" -//#include "proxmark3.h" -//#include "data.h" -//#include "ui.h" -//#include "graph.h" -//#include "cmdparser.h" -//#include "util.h" -//#include "cmdmain.h" -//#include "cmddata.h" -//uint8_t BinStream[MAX_GRAPH_TRACE_LEN]; -//uint8_t BinStreamLen; + + +uint8_t justNoise(uint8_t *BitStream, size_t size) +{ + static const uint8_t THRESHOLD = 123; + //test samples are not just noise + uint8_t justNoise1 = 1; + for(size_t idx=0; idx < size && justNoise1 ;idx++){ + justNoise1 = BitStream[idx] < THRESHOLD; + } + return justNoise1; +} + +//by marshmellow +//get high and low with passed in fuzz factor. also return noise test = 1 for passed or 0 for only noise +int getHiLo(uint8_t *BitStream, size_t size, int *high, int *low, uint8_t fuzzHi, uint8_t fuzzLo) +{ + *high=0; + *low=255; + // get high and low thresholds + for (int i=0; i < size; i++){ + if (BitStream[i] > *high) *high = BitStream[i]; + if (BitStream[i] < *low) *low = BitStream[i]; + } + if (*high < 123) return -1; // just noise + *high = (int)(((*high-128)*(((float)fuzzHi)/100))+128); + *low = (int)(((*low-128)*(((float)fuzzLo)/100))+128); + return 1; +} + +// by marshmellow +// pass bits to be tested in bits, length bits passed in bitLen, and parity type (even=0 | odd=1) in pType +// returns 1 if passed +uint8_t parityTest(uint32_t bits, uint8_t bitLen, uint8_t pType) +{ + uint8_t ans = 0; + for (uint8_t i = 0; i < bitLen; i++){ + ans ^= ((bits >> i) & 1); + } + //PrintAndLog("DEBUG: ans: %d, ptype: %d",ans,pType); + return (ans == pType); +} + +//by marshmellow +//search for given preamble in given BitStream and return 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; + for (int idx=0; idx < *size - pLen; idx++){ + if (memcmp(BitStream+idx, preamble, pLen) == 0){ + //first index found + foundCnt++; + if (foundCnt == 1){ + *startIdx = idx; + } + if (foundCnt == 2){ + *size = idx - *startIdx; + return 1; + } + } + } + return 0; +} + //by marshmellow //takes 1s and 0s and searches for EM410x format - output EM ID -uint64_t Em410xDecode(uint8_t *BitStream,uint32_t BitLen) +uint64_t Em410xDecode(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 - int high=0, low=0; - uint64_t lo=0; //hi=0, - + uint64_t lo=0; uint32_t i = 0; - uint32_t initLoopMax = 65; - if (initLoopMax>BitLen) initLoopMax=BitLen; - - for (;i < initLoopMax; ++i) //65 samples should be plenty to find high and low values - { - if (BitStream[i] > high) - high = BitStream[i]; - else if (BitStream[i] < low) - low = BitStream[i]; - } - if (((high !=1)||(low !=0))){ //allow only 1s and 0s - // PrintAndLog("no data found"); + if (BitStream[1]>1){ //allow only 1s and 0s + // PrintAndLog("no data found"); return 0; } - uint8_t parityTest=0; - // 111111111 bit pattern represent start of frame - uint8_t frame_marker_mask[] = {1,1,1,1,1,1,1,1,1}; + // 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 ii=0; - uint8_t resetCnt = 0; - while( (idx + 64) < BitLen) { - restart: - // search for a start of frame marker - if ( memcmp(BitStream+idx, frame_marker_mask, sizeof(frame_marker_mask)) == 0) - { // frame marker found - idx+=9;//sizeof(frame_marker_mask); - for (i=0; i<10;i++){ - for(ii=0; ii<5; ++ii){ - parityTest += BitStream[(i*5)+ii+idx]; - } - if (parityTest== ((parityTest>>1)<<1)){ - parityTest=0; - for (ii=0; ii<4;++ii){ - //hi = (hi<<1)|(lo>>31); - lo=(lo<<1LL)|(BitStream[(i*5)+ii+idx]); - } - //PrintAndLog("DEBUG: EM parity passed parity val: %d, i:%d, ii:%d,idx:%d, Buffer: %d%d%d%d%d,lo: %d",parityTest,i,ii,idx,BitStream[idx+ii+(i*5)-5],BitStream[idx+ii+(i*5)-4],BitStream[idx+ii+(i*5)-3],BitStream[idx+ii+(i*5)-2],BitStream[idx+ii+(i*5)-1],lo); - }else {//parity failed - //PrintAndLog("DEBUG: EM parity failed parity val: %d, i:%d, ii:%d,idx:%d, Buffer: %d%d%d%d%d",parityTest,i,ii,idx,BitStream[idx+ii+(i*5)-5],BitStream[idx+ii+(i*5)-4],BitStream[idx+ii+(i*5)-3],BitStream[idx+ii+(i*5)-2],BitStream[idx+ii+(i*5)-1]); - parityTest=0; - idx-=8; - if (resetCnt>5)return 0; - resetCnt++; - goto restart;//continue; - } + 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; + } + for (uint8_t ii=0; ii<4; ii++){ + lo = (lo << 1LL) | (BitStream[(i*5)+ii+idx]); } - //skip last 5 bit parity test for simplicity. - return lo; - }else{ - idx++; } + if (errChk != 0) return lo; + //skip last 5 bit parity test for simplicity. + // *size = 64; } return 0; } //by marshmellow //takes 2 arguments - clock and invert both as integers -//attempts to demodulate ask while decoding manchester +//attempts to demodulate ask while decoding manchester //prints binary found and saves in graphbuffer for further commands -int askmandemod(uint8_t * BinStream,uint32_t *BitLen,int *clk, int *invert) +int askmandemod(uint8_t *BinStream, size_t *size, int *clk, int *invert) { - uint32_t i; - //int invert=0; //invert default - int high = 0, low = 0; - *clk=DetectClock2(BinStream,(size_t)*BitLen,*clk); //clock default - uint8_t BitStream[252] = {0}; - - //sscanf(Cmd, "%i %i", &clk, &invert); - if (*clk<8) *clk =64; - if (*clk<32) *clk=32; - if (*invert != 0 && *invert != 1) *invert=0; - uint32_t initLoopMax = 200; - if (initLoopMax>*BitLen) initLoopMax=*BitLen; - // Detect high and lows - //PrintAndLog("Using Clock: %d and invert=%d",clk,invert); - for (i = 0; i < initLoopMax; ++i) //200 samples should be enough to find high and low values - { - if (BinStream[i] > high) - high = BinStream[i]; - else if (BinStream[i] < low) - low = BinStream[i]; - } - if ((high < 30) && ((high !=1)||(low !=-1))){ //throw away static - allow 1 and -1 (in case of threshold command first) - //PrintAndLog("no data found"); - return -1; - } - //13% fuzz in case highs and lows aren't clipped [marshmellow] - high=(int)(0.75*high); - low=(int)(0.75*low); - - //PrintAndLog("DEBUG - valid high: %d - valid low: %d",high,low); - int lastBit = 0; //set first clock check - uint32_t bitnum = 0; //output counter - uint8_t tol = 0; //clock tolerance adjust - waves will be accepted as within the clock if they fall + or - this value + clock from last valid wave - if (*clk==32)tol=1; //clock tolerance may not be needed anymore currently set to + or - 1 but could be increased for poor waves or removed entirely - uint32_t iii = 0; - uint32_t gLen = *BitLen; - if (gLen > 500) gLen=500; - uint8_t errCnt =0; - uint32_t bestStart = *BitLen; - uint32_t bestErrCnt = (*BitLen/1000); - //PrintAndLog("DEBUG - lastbit - %d",lastBit); - //loop to find first wave that works - for (iii=0; iii < gLen; ++iii){ - if ((BinStream[iii]>=high)||(BinStream[iii]<=low)){ - lastBit=iii-*clk; - bitnum=0; - //loop through to see if this start location works - for (i = iii; i < *BitLen; ++i) { - if ((BinStream[i] >= high) && ((i-lastBit)>(*clk-tol))){ - lastBit+=*clk; - BitStream[bitnum] = *invert; - bitnum++; - } else if ((BinStream[i] <= low) && ((i-lastBit)>(*clk-tol))){ - //low found and we are expecting a bar - lastBit+=*clk; - BitStream[bitnum] = 1-*invert; - bitnum++; - } else { - //mid value found or no bar supposed to be here - if ((i-lastBit)>(*clk+tol)){ - //should have hit a high or low based on clock!! - - - //debug - //PrintAndLog("DEBUG - no wave in expected area - location: %d, expected: %d-%d, lastBit: %d - resetting search",i,(lastBit+(clk-((int)(tol)))),(lastBit+(clk+((int)(tol)))),lastBit); - if (bitnum > 0){ - BitStream[bitnum]=77; - bitnum++; - } - + int i; + int clk2=*clk; + *clk=DetectASKClock(BinStream, *size, *clk); //clock default - errCnt++; - lastBit+=*clk;//skip over until hit too many errors - if (errCnt>((*BitLen/1000))){ //allow 1 error for every 1000 samples else start over - errCnt=0; - bitnum=0;//start over - break; - } - } - } - if (bitnum >250) break; - } - //we got more than 64 good bits and not all errors - if ((bitnum > (64+errCnt)) && (errCnt<(*BitLen/1000))) { - //possible good read - if (errCnt==0) break; //great read - finish - if (bestStart == iii) break; //if current run == bestErrCnt run (after exhausted testing) then finish - if (errCnt=gLen){ //exhausted test - //if there was a ok test go back to that one and re-run the best run (then dump after that run) - if (bestErrCnt < (*BitLen/1000)) iii=bestStart; - } + // if autodetected too low then adjust //MAY NEED ADJUSTMENT + if (clk2==0 && *clk<8) *clk =64; + if (clk2==0 && *clk<32) *clk=32; + if (*invert != 0 && *invert != 1) *invert=0; + uint32_t initLoopMax = 200; + if (initLoopMax > *size) initLoopMax=*size; + // Detect high and lows + // 25% fuzz in case highs and lows aren't clipped [marshmellow] + int high, low, ans; + ans = getHiLo(BinStream, initLoopMax, &high, &low, 75, 75); + if (ans<1) return -2; //just noise + + // PrintAndLog("DEBUG - valid high: %d - valid low: %d",high,low); + int lastBit = 0; //set first clock check + uint32_t bitnum = 0; //output counter + int tol = 0; //clock tolerance adjust - waves will be accepted as within the clock if they fall + or - this value + clock from last valid wave + if (*clk<=32)tol=1; //clock tolerance may not be needed anymore currently set to + or - 1 but could be increased for poor waves or removed entirely + int iii = 0; + uint32_t gLen = *size; + if (gLen > 3000) gLen=3000; + uint8_t errCnt =0; + uint32_t bestStart = *size; + uint32_t bestErrCnt = (*size/1000); + uint32_t maxErr = (*size/1000); + // PrintAndLog("DEBUG - lastbit - %d",lastBit); + // loop to find first wave that works + for (iii=0; iii < gLen; ++iii){ + if ((BinStream[iii] >= high) || (BinStream[iii] <= low)){ + lastBit=iii-*clk; + errCnt=0; + // loop through to see if this start location works + for (i = iii; i < *size; ++i) { + if ((BinStream[i] >= high) && ((i-lastBit) > (*clk-tol))){ + lastBit+=*clk; + } else if ((BinStream[i] <= low) && ((i-lastBit) > (*clk-tol))){ + //low found and we are expecting a bar + lastBit+=*clk; + } else { + //mid value found or no bar supposed to be here + if ((i-lastBit)>(*clk+tol)){ + //should have hit a high or low based on clock!! + + //debug + //PrintAndLog("DEBUG - no wave in expected area - location: %d, expected: %d-%d, lastBit: %d - resetting search",i,(lastBit+(clk-((int)(tol)))),(lastBit+(clk+((int)(tol)))),lastBit); + + errCnt++; + lastBit+=*clk;//skip over until hit too many errors + if (errCnt>(maxErr)) break; //allow 1 error for every 1000 samples else start over + } + } + if ((i-iii) >(400 * *clk)) break; //got plenty of bits + } + //we got more than 64 good bits and not all errors + if ((((i-iii)/ *clk) > (64+errCnt)) && (errCnt= high) && ((i-lastBit) > (*clk-tol))){ + lastBit += *clk; + BinStream[bitnum] = *invert; + bitnum++; + } else if ((BinStream[i] <= low) && ((i-lastBit) > (*clk-tol))){ + //low found and we are expecting a bar + lastBit+=*clk; + BinStream[bitnum] = 1-*invert; + bitnum++; + } else { + //mid value found or no bar supposed to be here + if ((i-lastBit)>(*clk+tol)){ + //should have hit a high or low based on clock!! + + //debug + //PrintAndLog("DEBUG - no wave in expected area - location: %d, expected: %d-%d, lastBit: %d - resetting search",i,(lastBit+(clk-((int)(tol)))),(lastBit+(clk+((int)(tol)))),lastBit); + if (bitnum > 0){ + BinStream[bitnum]=77; + bitnum++; + } + + lastBit+=*clk;//skip over error + } + } + if (bitnum >=400) break; + } + *size=bitnum; + } else{ + *invert=bestStart; + *clk=iii; + return -1; + } + return bestErrCnt; +} + +//by marshmellow +//encode binary data into binary manchester +int ManchesterEncode(uint8_t *BitStream, size_t size) +{ + size_t modIdx=20000, i=0; + if (size>modIdx) return -1; + for (size_t idx=0; idx < size; idx++){ + BitStream[idx+modIdx++] = BitStream[idx]; + BitStream[idx+modIdx++] = BitStream[idx]^1; } - if (bitnum>16){ - - // PrintAndLog("Data start pos:%d, lastBit:%d, stop pos:%d, numBits:%d",iii,lastBit,i,bitnum); - //move BitStream back to GraphBuffer - //ClearGraph(0); - for (i=0; i < bitnum; ++i){ - BinStream[i]=BitStream[i]; - } - *BitLen=bitnum; - //RepaintGraphWindow(); - //output - //if (errCnt>0){ - // PrintAndLog("# Errors during Demoding (shown as 77 in bit stream): %d",errCnt); - //} - // PrintAndLog("ASK decoded bitstream:"); - // Now output the bitstream to the scrollback by line of 16 bits - // printBitStream2(BitStream,bitnum); - // Em410xDecode(Cmd); - } - return errCnt; + for (; i<(size*2); i++){ + BitStream[i] = BitStream[i+20000]; + } + return i; } //by marshmellow //take 10 and 01 and manchester decode //run through 2 times and take least errCnt -int manrawdemod(uint8_t * BitStream, int *bitLen) +int manrawdecode(uint8_t * BitStream, size_t *size) { - uint8_t BitStream2[252]={0}; - int bitnum=0; - int errCnt =0; - int i=1; - int bestErr = 1000; - int bestRun = 0; - int finish = 0; - int ii=1; - for (ii=1;ii<3;++ii){ - i=1; - for (i=i+ii;i<*bitLen-2;i+=2){ - if(BitStream[i]==1 && (BitStream[i+1]==0)){ - BitStream2[bitnum++]=0; - } else if((BitStream[i]==0)&& BitStream[i+1]==1){ - BitStream2[bitnum++]=1; - } else { - BitStream2[bitnum++]=77; - errCnt++; - } - if(bitnum>250) break; + int bitnum=0; + int errCnt =0; + int i=1; + int bestErr = 1000; + int bestRun = 0; + int ii=1; + for (ii=1;ii<3;++ii){ + i=1; + 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){ + } else { + errCnt++; + } + if(bitnum>300) break; } if (bestErr>errCnt){ - bestErr=errCnt; - bestRun=ii; - } - if (ii>1 || finish==1) { - if (bestRun==ii) { - break; - } else{ - ii=bestRun-1; - finish=1; - } + bestErr=errCnt; + bestRun=ii; } errCnt=0; - bitnum=0; - } - errCnt=bestErr; - if (errCnt<20){ - for (i=0; i300) break; + } + *size=bitnum; + } + return errCnt; +} + +//by marshmellow +//take 01 or 10 = 0 and 11 or 00 = 1 +int BiphaseRawDecode(uint8_t *BitStream, size_t *size, int offset, int invert) +{ + uint8_t bitnum=0; + uint32_t errCnt =0; + uint32_t i; + i=offset; + for (;i<*size-2; i+=2){ + 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)){ + BitStream[bitnum++]=invert; + } else { + BitStream[bitnum++]=77; + errCnt++; + } + if(bitnum>250) break; + } + *size=bitnum; + return errCnt; } //by marshmellow //takes 2 arguments - clock and invert both as integers //attempts to demodulate ask only //prints binary found and saves in graphbuffer for further commands -int askrawdemod(uint8_t *BinStream, int *bitLen,int *clk, int *invert) +int askrawdemod(uint8_t *BinStream, size_t *size, int *clk, int *invert) { - uint32_t i; - // int invert=0; //invert default - int high = 0, low = 0; - *clk=DetectClock2(BinStream,*bitLen,*clk); //clock default - uint8_t BitStream[502] = {0}; - - if (*clk<8) *clk =64; - if (*clk<32) *clk=32; - if (*invert != 0 && *invert != 1) *invert =0; - uint32_t initLoopMax = 200; - if (initLoopMax>*bitLen) initLoopMax=*bitLen; - // Detect high and lows - for (i = 0; i < initLoopMax; ++i) //200 samples should be plenty to find high and low values - { - if (BinStream[i] > high) - high = BinStream[i]; - else if (BinStream[i] < low) - low = BinStream[i]; - } - if ((high < 30) && ((high !=1)||(low !=-1))){ //throw away static - allow 1 and -1 (in case of threshold command first) - // PrintAndLog("no data found"); - return -1; - } - //25% fuzz in case highs and lows aren't clipped [marshmellow] - high=(int)(0.75*high); - low=(int)(0.75*low); - - //PrintAndLog("DEBUG - valid high: %d - valid low: %d",high,low); - int lastBit = 0; //set first clock check - uint32_t bitnum = 0; //output counter - uint8_t tol = 0; //clock tolerance adjust - waves will be accepted as within the clock if they fall + or - this value + clock from last valid wave - if (*clk==32)tol=1; //clock tolerance may not be needed anymore currently set to + or - 1 but could be increased for poor waves or removed entirely - uint32_t iii = 0; - uint32_t gLen = *bitLen; - if (gLen > 500) gLen=500; - uint8_t errCnt =0; - uint32_t bestStart = *bitLen; - uint32_t bestErrCnt = (*bitLen/1000); - uint8_t midBit=0; - //PrintAndLog("DEBUG - lastbit - %d",lastBit); - //loop to find first wave that works - for (iii=0; iii < gLen; ++iii){ - if ((BinStream[iii]>=high)||(BinStream[iii]<=low)){ - lastBit=iii-*clk; - //loop through to see if this start location works - for (i = iii; i < *bitLen; ++i) { - if ((BinStream[i] >= high) && ((i-lastBit)>(*clk-tol))){ - lastBit+=*clk; - BitStream[bitnum] = *invert; - bitnum++; - midBit=0; - } else if ((BinStream[i] <= low) && ((i-lastBit)>(*clk-tol))){ - //low found and we are expecting a bar - lastBit+=*clk; - BitStream[bitnum] = 1-*invert; - bitnum++; - midBit=0; - } else if ((BinStream[i]<=low) && (midBit==0) && ((i-lastBit)>((*clk/2)-tol))){ - //mid bar? - midBit=1; - BitStream[bitnum]= 1-*invert; - bitnum++; - } else if ((BinStream[i]>=high)&&(midBit==0) && ((i-lastBit)>((*clk/2)-tol))){ - //mid bar? - midBit=1; - BitStream[bitnum]= *invert; - bitnum++; - } else if ((i-lastBit)>((*clk/2)+tol)&&(midBit==0)){ - //no mid bar found - midBit=1; - BitStream[bitnum]= BitStream[bitnum-1]; - bitnum++; - } else { - //mid value found or no bar supposed to be here - - if ((i-lastBit)>(*clk+tol)){ - //should have hit a high or low based on clock!! - //debug - //PrintAndLog("DEBUG - no wave in expected area - location: %d, expected: %d-%d, lastBit: %d - resetting search",i,(lastBit+(clk-((int)(tol)))),(lastBit+(clk+((int)(tol)))),lastBit); - if (bitnum > 0){ - BitStream[bitnum]=77; - bitnum++; - } - + uint32_t i; + // int invert=0; //invert default + int clk2 = *clk; + *clk=DetectASKClock(BinStream, *size, *clk); //clock default + //uint8_t BitStream[502] = {0}; - errCnt++; - lastBit+=*clk;//skip over until hit too many errors - if (errCnt>((*bitLen/1000))){ //allow 1 error for every 1000 samples else start over - errCnt=0; - bitnum=0;//start over - break; - } - } - } - if (bitnum>500) break; - } - //we got more than 64 good bits and not all errors - if ((bitnum > (64+errCnt)) && (errCnt<(*bitLen/1000))) { - //possible good read - if (errCnt==0) break; //great read - finish - if (bestStart == iii) break; //if current run == bestErrCnt run (after exhausted testing) then finish - if (errCnt=gLen){ //exhausted test - //if there was a ok test go back to that one and re-run the best run (then dump after that run) - if (bestErrCnt < (*bitLen/1000)) iii=bestStart; - } - } - if (bitnum>16){ - - // PrintAndLog("Data start pos:%d, lastBit:%d, stop pos:%d, numBits:%d",iii,lastBit,i,bitnum); - //move BitStream back to BinStream - // ClearGraph(0); - for (i=0; i < bitnum; ++i){ - BinStream[i]=BitStream[i]; - } - *bitLen=bitnum; - // RepaintGraphWindow(); - //output - // if (errCnt>0){ - // PrintAndLog("# Errors during Demoding (shown as 77 in bit stream): %d",errCnt); - // } - // PrintAndLog("ASK decoded bitstream:"); - // Now output the bitstream to the scrollback by line of 16 bits - // printBitStream2(BitStream,bitnum); - //int errCnt=0; - //errCnt=manrawdemod(BitStream,bitnum); - - // Em410xDecode(Cmd); - } else return -1; - return errCnt; + //HACK: if clock not detected correctly - default + if (clk2==0 && *clk<8) *clk =64; + if (clk2==0 && *clk<32 && clk2==0) *clk=32; + if (*invert != 0 && *invert != 1) *invert =0; + uint32_t initLoopMax = 200; + if (initLoopMax > *size) initLoopMax=*size; + // Detect high and lows + //25% fuzz in case highs and lows aren't clipped [marshmellow] + int high, low, ans; + ans = getHiLo(BinStream, initLoopMax, &high, &low, 75, 75); + if (ans<1) return -2; //just noise + + //PrintAndLog("DEBUG - valid high: %d - valid low: %d",high,low); + int lastBit = 0; //set first clock check + uint32_t bitnum = 0; //output counter + uint8_t tol = 0; //clock tolerance adjust - waves will be accepted as within the clock + // if they fall + or - this value + clock from last valid wave + if (*clk == 32) tol=1; //clock tolerance may not be needed anymore currently set to + // + or - 1 but could be increased for poor waves or removed entirely + uint32_t iii = 0; + uint32_t gLen = *size; + if (gLen > 500) gLen=500; + uint8_t errCnt =0; + uint32_t bestStart = *size; + uint32_t bestErrCnt = (*size/1000); + uint32_t maxErr = bestErrCnt; + uint8_t midBit=0; + //PrintAndLog("DEBUG - lastbit - %d",lastBit); + //loop to find first wave that works + for (iii=0; iii < gLen; ++iii){ + if ((BinStream[iii]>=high) || (BinStream[iii]<=low)){ + lastBit=iii-*clk; + //loop through to see if this start location works + for (i = iii; i < *size; ++i) { + if ((BinStream[i] >= high) && ((i-lastBit)>(*clk-tol))){ + lastBit+=*clk; + midBit=0; + } else if ((BinStream[i] <= low) && ((i-lastBit)>(*clk-tol))){ + //low found and we are expecting a bar + lastBit+=*clk; + midBit=0; + } else if ((BinStream[i]<=low) && (midBit==0) && ((i-lastBit)>((*clk/2)-tol))){ + //mid bar? + midBit=1; + } else if ((BinStream[i]>=high) && (midBit==0) && ((i-lastBit)>((*clk/2)-tol))){ + //mid bar? + midBit=1; + } else if ((i-lastBit)>((*clk/2)+tol) && (midBit==0)){ + //no mid bar found + midBit=1; + } else { + //mid value found or no bar supposed to be here + + if ((i-lastBit)>(*clk+tol)){ + //should have hit a high or low based on clock!! + //debug + //PrintAndLog("DEBUG - no wave in expected area - location: %d, expected: %d-%d, lastBit: %d - resetting search",i,(lastBit+(clk-((int)(tol)))),(lastBit+(clk+((int)(tol)))),lastBit); + + errCnt++; + lastBit+=*clk;//skip over until hit too many errors + if (errCnt > ((*size/1000))){ //allow 1 error for every 1000 samples else start over + errCnt=0; + break; + } + } + } + if ((i-iii)>(500 * *clk)) break; //got enough bits + } + //we got more than 64 good bits and not all errors + if ((((i-iii)/ *clk) > (64+errCnt)) && (errCnt<(*size/1000))) { + //possible good read + if (errCnt==0){ + bestStart=iii; + bestErrCnt=errCnt; + break; //great read - finish + } + if (errCnt= high) && ((i-lastBit) > (*clk-tol))){ + lastBit += *clk; + BinStream[bitnum] = *invert; + bitnum++; + midBit=0; + } else if ((BinStream[i] <= low) && ((i-lastBit) > (*clk-tol))){ + //low found and we are expecting a bar + lastBit+=*clk; + BinStream[bitnum] = 1-*invert; + bitnum++; + midBit=0; + } else if ((BinStream[i]<=low) && (midBit==0) && ((i-lastBit)>((*clk/2)-tol))){ + //mid bar? + midBit=1; + BinStream[bitnum] = 1 - *invert; + bitnum++; + } else if ((BinStream[i]>=high) && (midBit==0) && ((i-lastBit)>((*clk/2)-tol))){ + //mid bar? + midBit=1; + BinStream[bitnum] = *invert; + bitnum++; + } else if ((i-lastBit)>((*clk/2)+tol) && (midBit==0)){ + //no mid bar found + midBit=1; + if (bitnum!=0) BinStream[bitnum] = BinStream[bitnum-1]; + bitnum++; + + } else { + //mid value found or no bar supposed to be here + if ((i-lastBit)>(*clk+tol)){ + //should have hit a high or low based on clock!! + + //debug + //PrintAndLog("DEBUG - no wave in expected area - location: %d, expected: %d-%d, lastBit: %d - resetting search",i,(lastBit+(clk-((int)(tol)))),(lastBit+(clk+((int)(tol)))),lastBit); + if (bitnum > 0){ + BinStream[bitnum]=77; + bitnum++; + } + + lastBit+=*clk;//skip over error + } + } + if (bitnum >=400) break; + } + *size=bitnum; + } else{ + *invert=bestStart; + *clk=iii; + return -1; + } + return bestErrCnt; } -//translate wave to 11111100000 (1 for each short wave 0 for each long wave) -size_t fsk_wave_demod(uint8_t * dest, size_t size) +//translate wave to 11111100000 (1 for each short wave 0 for each long wave) +size_t fsk_wave_demod(uint8_t * dest, size_t size, uint8_t fchigh, uint8_t fclow) { uint32_t last_transition = 0; uint32_t idx = 1; - uint32_t maxVal=0; - - // we do care about the actual theshold value as sometimes near the center of the - // wave we may get static that changes direction of wave for one value - // if our value is too low it might affect the read. and if our tag or - // antenna is weak a setting too high might not see anything. [marshmellow] - if (size<100) return 0; - for(idx=1; idx<100; idx++){ - if(maxVal1 transition if (dest[idx-1] < dest[idx]) { // 0 -> 1 transition - if (idx-last_transition<6){ //0-5 = garbage noise + if ((idx-last_transition)<(fclow-2)){ //0-5 = garbage noise //do nothing with extra garbage - } else if (idx-last_transition < 9) { //6-8 = 8 waves + } else if ((idx-last_transition) < (fchigh-1)) { //6-8 = 8 waves dest[numBits]=1; } else { //9+ = 10 waves dest[numBits]=0; @@ -464,12 +522,13 @@ size_t fsk_wave_demod(uint8_t * dest, size_t size) uint32_t myround2(float f) { - if (f >= 2000) return 2000;//something bad happened - return (uint32_t) (f + (float)0.5); + if (f >= 2000) return 2000;//something bad happened + return (uint32_t) (f + (float)0.5); } -//translate 11111100000 to 10 -size_t aggregate_bits(uint8_t *dest,size_t size, uint8_t rfLen, uint8_t maxConsequtiveBits, uint8_t invert )// uint8_t h2l_crossing_value,uint8_t l2h_crossing_value, +//translate 11111100000 to 10 +size_t aggregate_bits(uint8_t *dest, size_t size, uint8_t rfLen, uint8_t maxConsequtiveBits, + uint8_t invert, uint8_t fchigh, uint8_t fclow) { uint8_t lastval=dest[0]; uint32_t idx=0; @@ -484,21 +543,19 @@ size_t aggregate_bits(uint8_t *dest,size_t size, uint8_t rfLen, uint8_t maxCons } //if lastval was 1, we have a 1->0 crossing if ( dest[idx-1]==1 ) { - n=myround2((float)(n+1)/((float)(rfLen)/(float)8)); - //n=(n+1) / h2l_crossing_value; + n=myround2((float)(n+1)/((float)(rfLen)/(float)fclow)); } else {// 0->1 crossing - n=myround2((float)(n+1)/((float)(rfLen-2)/(float)10)); //-2 for fudge factor - //n=(n+1) / l2h_crossing_value; + n=myround2((float)(n+1)/((float)(rfLen-1)/(float)fchigh)); //-1 for fudge factor } if (n == 0) n = 1; - if(n < maxConsequtiveBits) //Consecutive + if(n < maxConsequtiveBits) //Consecutive { - if(invert==0){ //invert bits + if(invert==0){ //invert bits memset(dest+numBits, dest[idx-1] , n); }else{ - memset(dest+numBits, dest[idx-1]^1 , n); - } + memset(dest+numBits, dest[idx-1]^1 , n); + } numBits += n; } n=0; @@ -508,78 +565,79 @@ size_t aggregate_bits(uint8_t *dest,size_t size, uint8_t rfLen, uint8_t maxCons } //by marshmellow (from holiman's base) // full fsk demod from GraphBuffer wave to decoded 1s and 0s (no mandemod) -int fskdemod(uint8_t *dest, size_t size, uint8_t rfLen, uint8_t invert) +int fskdemod(uint8_t *dest, size_t size, uint8_t rfLen, uint8_t invert, uint8_t fchigh, uint8_t fclow) { - //uint8_t h2l_crossing_value = 6; - //uint8_t l2h_crossing_value = 5; - - // if (rfLen==64) //currently only know settings for RF/64 change from default if option entered - // { - // h2l_crossing_value=8; //or 8 as 64/8 = 8 - // l2h_crossing_value=6; //or 6.4 as 64/10 = 6.4 - // } - // size_t size = GraphTraceLen; - // FSK demodulator - size = fsk_wave_demod(dest, size); - size = aggregate_bits(dest, size,rfLen,192,invert); - // size = aggregate_bits(size, h2l_crossing_value, l2h_crossing_value,192, invert); //192=no limit to same values - //done messing with GraphBuffer - repaint - //RepaintGraphWindow(); - return size; + // FSK demodulator + size = fsk_wave_demod(dest, size, fchigh, fclow); + size = aggregate_bits(dest, size, rfLen, 192, invert, fchigh, fclow); + return size; } + // loop to get raw HID waveform then FSK demodulate the TAG ID from it -int HIDdemodFSK(uint8_t *dest, size_t size, uint32_t *hi2, uint32_t *hi, uint32_t *lo) +int HIDdemodFSK(uint8_t *dest, size_t *size, uint32_t *hi2, uint32_t *hi, uint32_t *lo) { + if (justNoise(dest, *size)) return -1; + + size_t numStart=0, size2=*size, startIdx=0; + // FSK demodulator + *size = fskdemod(dest, size2,50,1,10,8); //fsk2a + if (*size < 96) return -2; + // 00011101 bit pattern represent start of frame, 01 pattern represents a 0 and 10 represents a 1 + uint8_t preamble[] = {0,0,0,1,1,1,0,1}; + // find bitstring in array + uint8_t errChk = preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx); + if (errChk == 0) return -3; //preamble not found + + numStart = startIdx + sizeof(preamble); + // final loop, go over previously decoded FSK data and manchester decode into usable tag ID + for (size_t idx = numStart; (idx-numStart) < *size - sizeof(preamble); idx+=2){ + if (dest[idx] == dest[idx+1]){ + return -4; //not manchester data + } + *hi2 = (*hi2<<1)|(*hi>>31); + *hi = (*hi<<1)|(*lo>>31); + //Then, shift in a 0 or one into low + if (dest[idx] && !dest[idx+1]) // 1 0 + *lo=(*lo<<1)|1; + else // 0 1 + *lo=(*lo<<1)|0; + } + return (int)startIdx; +} + +// loop to get raw paradox waveform then FSK demodulate the TAG ID from it +int ParadoxdemodFSK(uint8_t *dest, size_t *size, uint32_t *hi2, uint32_t *hi, uint32_t *lo) +{ + if (justNoise(dest, *size)) return -1; - size_t idx=0; //, found=0; //size=0, + size_t numStart=0, size2=*size, startIdx=0; // FSK demodulator - size = fskdemod(dest, size,50,0); - - // final loop, go over previously decoded manchester data and decode into usable tag ID - // 111000 bit pattern represent start of frame, 01 pattern represents a 1 and 10 represents a 0 - uint8_t frame_marker_mask[] = {1,1,1,0,0,0}; - int numshifts = 0; - idx = 0; - //one scan - while( idx + sizeof(frame_marker_mask) < size) { - // search for a start of frame marker - if ( memcmp(dest+idx, frame_marker_mask, sizeof(frame_marker_mask)) == 0) - { // frame marker found - idx+=sizeof(frame_marker_mask); - while(dest[idx] != dest[idx+1] && idx < size-2) - { - // Keep going until next frame marker (or error) - // Shift in a bit. Start by shifting high registers - *hi2 = (*hi2<<1)|(*hi>>31); - *hi = (*hi<<1)|(*lo>>31); - //Then, shift in a 0 or one into low - if (dest[idx] && !dest[idx+1]) // 1 0 - *lo=(*lo<<1)|0; - else // 0 1 - *lo=(*lo<<1)|1; - numshifts++; - idx += 2; - } - // Hopefully, we read a tag and hit upon the next frame marker - if(idx + sizeof(frame_marker_mask) < size) - { - if ( memcmp(dest+idx, frame_marker_mask, sizeof(frame_marker_mask)) == 0) - { - //good return - return idx; - } - } - // reset - *hi2 = *hi = *lo = 0; - numshifts = 0; - }else { - idx++; - } + *size = fskdemod(dest, size2,50,1,10,8); //fsk2a + if (*size < 96) return -2; + + // 00001111 bit pattern represent start of frame, 01 pattern represents a 0 and 10 represents a 1 + uint8_t preamble[] = {0,0,0,0,1,1,1,1}; + + uint8_t errChk = preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx); + if (errChk == 0) return -3; //preamble not found + + numStart = startIdx + sizeof(preamble); + // final loop, go over previously decoded FSK data and manchester decode into usable tag ID + for (size_t idx = numStart; (idx-numStart) < *size - sizeof(preamble); idx+=2){ + if (dest[idx] == dest[idx+1]) + return -4; //not manchester data + *hi2 = (*hi2<<1)|(*hi>>31); + *hi = (*hi<<1)|(*lo>>31); + //Then, shift in a 0 or one into low + if (dest[idx] && !dest[idx+1]) // 1 0 + *lo=(*lo<<1)|1; + else // 0 1 + *lo=(*lo<<1)|0; } - return -1; + return (int)startIdx; } -uint32_t bytebits_to_byte(uint8_t* src, int numbits) +uint32_t bytebits_to_byte(uint8_t* src, size_t numbits) { uint32_t num = 0; for(int i = 0 ; i < numbits ; i++) @@ -592,103 +650,681 @@ uint32_t bytebits_to_byte(uint8_t* src, int numbits) int IOdemodFSK(uint8_t *dest, size_t size) { - uint32_t idx=0; + if (justNoise(dest, size)) return -1; //make sure buffer has data - if (size < 64) return -1; - //test samples are not just noise - uint8_t testMax=0; - for(idx=0;idx<64;idx++){ - if (testMax170){ - // FSK demodulator - size = fskdemod(dest, size,64,1); - //Index map - //0 10 20 30 40 50 60 - //| | | | | | | - //01234567 8 90123456 7 89012345 6 78901234 5 67890123 4 56789012 3 45678901 23 - //----------------------------------------------------------------------------- - //00000000 0 11110000 1 facility 1 version* 1 code*one 1 code*two 1 ???????? 11 - // - //XSF(version)facility:codeone+codetwo - //Handle the data - uint8_t mask[] = {0,0,0,0,0,0,0,0,0,1}; - for( idx=0; idx < (size - 74); idx++) { - if ( memcmp(dest + idx, mask, sizeof(mask))==0) { - //frame marker found - if (!dest[idx+8] && dest[idx+17]==1 && dest[idx+26]==1 && dest[idx+35]==1 && dest[idx+44]==1 && dest[idx+53]==1){ - //confirmed proper separator bits found - //return start position - return (int) idx; - } - } + return -5; +} + +// by marshmellow +// takes a array of binary values, start position, length of bits per parity (includes parity bit), +// Parity Type (1 for odd 0 for even), and binary Length (length to run) +size_t removeParity(uint8_t *BitStream, size_t startIdx, uint8_t pLen, uint8_t pType, size_t bLen) +{ + uint32_t parityWd = 0; + size_t j = 0, bitCnt = 0; + for (int word = 0; word < (bLen); word+=pLen){ + for (int bit=0; bit < pLen; bit++){ + parityWd = (parityWd << 1) | BitStream[startIdx+word+bit]; + BitStream[j++] = (BitStream[startIdx+word+bit]); } - } - return 0; + j--; + // if parity fails then return 0 + if (parityTest(parityWd, pLen, pType) == 0) return -1; + bitCnt+=(pLen-1); + parityWd = 0; + } + // if we got here then all the parities passed + //return ID start index and size + return bitCnt; +} + +// by marshmellow +// FSK Demod then try to locate an AWID ID +int AWIDdemodFSK(uint8_t *dest, size_t *size) +{ + //make sure buffer has enough data + if (*size < 96*50) return -1; + + if (justNoise(dest, *size)) return -2; + + // FSK demodulator + *size = fskdemod(dest, *size, 50, 1, 10, 8); // fsk2a RF/50 + if (*size < 96) return -3; //did we get a good demod? + + uint8_t preamble[] = {0,0,0,0,0,0,0,1}; + size_t startIdx = 0; + uint8_t errChk = preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx); + if (errChk == 0) return -4; //preamble not found + if (*size != 96) return -5; + return (int)startIdx; +} + +// by marshmellow +// FSK Demod then try to locate an Farpointe Data (pyramid) ID +int PyramiddemodFSK(uint8_t *dest, size_t *size) +{ + //make sure buffer has data + if (*size < 128*50) return -5; + + //test samples are not just noise + if (justNoise(dest, *size)) return -1; + + // FSK demodulator + *size = fskdemod(dest, *size, 50, 1, 10, 8); // fsk2a RF/50 + if (*size < 128) return -2; //did we get a good demod? + + uint8_t preamble[] = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1}; + size_t startIdx = 0; + uint8_t errChk = preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx); + if (errChk == 0) return -4; //preamble not found + if (*size != 128) return -3; + return (int)startIdx; } // 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? -int DetectClock2(uint8_t dest[], size_t size, int clock) +int DetectASKClock(uint8_t dest[], size_t size, int clock) { int i=0; - int peak=0; - int low=0; - int clk[]={16,32,40,50,64,100,128,256}; + int clk[]={8,16,32,40,50,64,100,128,256}; + int loopCnt = 256; //don't need to loop through entire array... + if (sizepeak){ - peak = dest[i]; - } - if(dest[i]=peak) || (dest[ii]<=low)){ - errCnt[clkCnt]=0; - for (i=0; i<((int)(size/clk[clkCnt])-1); ++i){ + bestErr[clkCnt]=1000; + //try lining up the peaks by moving starting point (try first 256) + for (ii=0; ii < loopCnt; ++ii){ + if ((dest[ii] >= peak) || (dest[ii] <= low)){ + errCnt=0; + // now that we have the first one lined up test rest of wave array + for (i=0; i<((int)((size-ii-tol)/clk[clkCnt])-1); ++i){ if (dest[ii+(i*clk[clkCnt])]>=peak || dest[ii+(i*clk[clkCnt])]<=low){ - }else if(dest[ii+(i*clk[clkCnt])-tol]>=peak || dest[ii+(i*clk[clkCnt])-tol]<=low){ + }else if(dest[ii+(i*clk[clkCnt])-tol]>=peak || dest[ii+(i*clk[clkCnt])-tol]<=low){ }else if(dest[ii+(i*clk[clkCnt])+tol]>=peak || dest[ii+(i*clk[clkCnt])+tol]<=low){ }else{ //error no peak detected - errCnt[clkCnt]++; - } + errCnt++; + } } - if(errCnt[clkCnt]==0) return clk[clkCnt]; - if(errCnt[clkCnt]= peak) || (dest[ii] <= low)){ + errCnt=0; + peakcnt=0; + // now that we have the first one lined up test rest of wave array + for (i=0; i < ((int)((size-ii-tol)/clk[clkCnt])-1); ++i){ + if (dest[ii+(i*clk[clkCnt])]>=peak || dest[ii+(i*clk[clkCnt])]<=low){ + peakcnt++; + }else if(dest[ii+(i*clk[clkCnt])-tol]>=peak || dest[ii+(i*clk[clkCnt])-tol]<=low){ + peakcnt++; + }else if(dest[ii+(i*clk[clkCnt])+tol]>=peak || dest[ii+(i*clk[clkCnt])+tol]<=low){ + peakcnt++; + }else{ //error no peak detected + errCnt++; + } + } + if(peakcnt>peaksdet[clkCnt]) { + peaksdet[clkCnt]=peakcnt; + bestErr[clkCnt]=errCnt; + } + } + } + } + int iii=0; + int best=0; + //int ratio2; //debug + int ratio; + //int bits; + for (iii=0; iii < 7; ++iii){ + ratio=1000; + //ratio2=1000; //debug + //bits=size/clk[iii]; //debug + if (peaksdet[iii] > 0){ + ratio=bestErr[iii]/peaksdet[iii]; + if (((bestErr[best]/peaksdet[best]) > (ratio)+1)){ + best = iii; + } + //ratio2=bits/peaksdet[iii]; //debug + } + //PrintAndLog("DEBUG: Clk: %d, peaks: %d, errs: %d, bestClk: %d, ratio: %d, bits: %d, peakbitr: %d",clk[iii],peaksdet[iii],bestErr[iii],clk[best],ratio, bits,ratio2); + } + return clk[best]; +} + +// by marshmellow (attempt to get rid of high immediately after a low) +void pskCleanWave(uint8_t *BitStream, size_t size) +{ + int i; + int gap = 4; + int newLow=0; + int newHigh=0; + int high, low; + getHiLo(BitStream, size, &high, &low, 80, 90); + + for (i=0; i < size; ++i){ + if (newLow == 1){ + if (BitStream[i]>low){ + BitStream[i]=low+8; + gap--; + } + if (gap == 0){ + newLow=0; + gap=4; + } + }else if (newHigh == 1){ + if (BitStream[i]= high) newHigh=1; + } + return; +} + +// by marshmellow +// convert psk1 demod to psk2 demod +// only transition waves are 1s +void psk1TOpsk2(uint8_t *BitStream, size_t size) +{ + size_t i=1; + uint8_t lastBit=BitStream[0]; + for (; i=high) || (dest[iii]<=low)){ + lastBit=iii-*clk; + //loop through to see if this start location works + 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)){ + bitHigh=1; + lastBit+=*clk; + ignorewin=*clk/8; + bitnum++; + //else if low bar found and we are at a clock point + }else if ((dest[i]<=low ) && (i>=lastBit+*clk-tol && i<=lastBit+*clk+tol)){ + bitHigh=1; + lastBit+=*clk; + ignorewin=*clk/8; + bitnum++; + //else if no bars found + }else if(dest[i] < high && dest[i] > low) { + if (ignorewin==0){ + bitHigh=0; + }else ignorewin--; + //if we are past a clock point + if (i >= lastBit+*clk+tol){ //clock val + lastBit+=*clk; + bitnum++; + } + //else if bar found but we are not at a clock bit and we did not just have a clock bit + }else if ((dest[i]>=high || dest[i]<=low) && (ilastBit+*clk+tol) && (bitHigh==0)){ + //error bar found no clock... + errCnt++; + } + if (bitnum>=1000) break; + } + //we got more than 64 good bits and not all errors + if ((bitnum > (64+errCnt)) && (errCnt < (maxErr))) { + //possible good read + if (errCnt == 0){ + bestStart = iii; + bestErrCnt = errCnt; + break; //great read - finish + } + if (errCnt < bestErrCnt){ //set this as new best run + bestErrCnt = errCnt; + bestStart = iii; + } + } + } + } + if (bestErrCnt < maxErr){ + //best run is good enough set to best run and set overwrite BinStream + iii=bestStart; + lastBit=bestStart-*clk; + bitnum=0; + 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)){ + bitHigh=1; + lastBit+=*clk; + curBit=1-*invert; + dest[bitnum]=curBit; + ignorewin=*clk/8; + bitnum++; + //else if low bar found and we are at a clock point + }else if ((dest[i]<=low ) && (i>=lastBit+*clk-tol && i<=lastBit+*clk+tol)){ + bitHigh=1; + lastBit+=*clk; + curBit=*invert; + dest[bitnum]=curBit; + ignorewin=*clk/8; + bitnum++; + //else if no bars found + }else if(dest[i]low) { + if (ignorewin==0){ + bitHigh=0; + }else ignorewin--; + //if we are past a clock point + if (i>=lastBit+*clk+tol){ //clock val + lastBit+=*clk; + dest[bitnum]=curBit; + bitnum++; + } + //else if bar found but we are not at a clock bit and we did not just have a clock bit + }else if ((dest[i]>=high || dest[i]<=low) && ((ilastBit+*clk+tol)) && (bitHigh==0)){ + //error bar found no clock... + bitHigh=1; + dest[bitnum]=77; + bitnum++; + errCnt++; + } + if (bitnum >=1000) break; + } + *size=bitnum; + } else{ + *size=bitnum; + *clk=bestStart; + return -1; + } + + if (bitnum>16){ + *size=bitnum; + } else return -1; + return errCnt; +} + +//by marshmellow +//detects the bit clock for FSK given the high and low Field Clocks +uint8_t detectFSKClk(uint8_t *BitStream, size_t size, uint8_t fcHigh, uint8_t fcLow) +{ + uint8_t clk[] = {8,16,32,40,50,64,100,128,0}; + uint16_t rfLens[] = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0}; + uint8_t rfCnts[] = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0}; + uint8_t rfLensFnd = 0; + uint8_t lastFCcnt=0; + uint32_t fcCounter = 0; + uint16_t rfCounter = 0; + uint8_t firstBitFnd = 0; + size_t i; + + uint8_t fcTol = (uint8_t)(0.5+(float)(fcHigh-fcLow)/2); + rfLensFnd=0; + fcCounter=0; + rfCounter=0; + firstBitFnd=0; + //PrintAndLog("DEBUG: fcTol: %d",fcTol); + // prime i to first up transition + for (i = 1; i < size-1; i++) + if (BitStream[i] > BitStream[i-1] && BitStream[i]>=BitStream[i+1]) + break; + + for (; i < size-1; i++){ + if (BitStream[i] > BitStream[i-1] && BitStream[i]>=BitStream[i+1]){ + // new peak + fcCounter++; + rfCounter++; + // if we got less than the small fc + tolerance then set it to the small fc + if (fcCounter < fcLow+fcTol) + fcCounter = fcLow; + else //set it to the large fc + fcCounter = fcHigh; + + //look for bit clock (rf/xx) + if ((fcCounterlastFCcnt)){ + //not the same size as the last wave - start of new bit sequence + + if (firstBitFnd>1){ //skip first wave change - probably not a complete bit + for (int ii=0; ii<15; ii++){ + if (rfLens[ii]==rfCounter){ + rfCnts[ii]++; + rfCounter=0; + break; + } + } + if (rfCounter>0 && rfLensFnd<15){ + //PrintAndLog("DEBUG: rfCntr %d, fcCntr %d",rfCounter,fcCounter); + rfCnts[rfLensFnd]++; + rfLens[rfLensFnd++]=rfCounter; + } + } else { + firstBitFnd++; + } + rfCounter=0; + lastFCcnt=fcCounter; + } + fcCounter=0; + } else { + // count sample + fcCounter++; + rfCounter++; + } + } + uint8_t rfHighest=15, rfHighest2=15, rfHighest3=15; + + for (i=0; i<15; i++){ + //PrintAndLog("DEBUG: RF %d, cnts %d",rfLens[i], rfCnts[i]); + //get highest 2 RF values (might need to get more values to compare or compare all?) + if (rfCnts[i]>rfCnts[rfHighest]){ + rfHighest3=rfHighest2; + rfHighest2=rfHighest; + rfHighest=i; + } else if(rfCnts[i]>rfCnts[rfHighest2]){ + rfHighest3=rfHighest2; + rfHighest2=i; + } else if(rfCnts[i]>rfCnts[rfHighest3]){ + rfHighest3=i; + } + } + // set allowed clock remainder tolerance to be 1 large field clock length+1 + // we could have mistakenly made a 9 a 10 instead of an 8 or visa versa so rfLens could be 1 FC off + uint8_t tol1 = fcHigh+1; + + //PrintAndLog("DEBUG: hightest: 1 %d, 2 %d, 3 %d",rfLens[rfHighest],rfLens[rfHighest2],rfLens[rfHighest3]); + + // loop to find the highest clock that has a remainder less than the tolerance + // compare samples counted divided by + int ii=7; + for (; ii>=0; ii--){ + if (rfLens[rfHighest] % clk[ii] < tol1 || rfLens[rfHighest] % clk[ii] > clk[ii]-tol1){ + if (rfLens[rfHighest2] % clk[ii] < tol1 || rfLens[rfHighest2] % clk[ii] > clk[ii]-tol1){ + if (rfLens[rfHighest3] % clk[ii] < tol1 || rfLens[rfHighest3] % clk[ii] > clk[ii]-tol1){ + break; + } + } + } + } + + if (ii<0) return 0; // oops we went too far + + return clk[ii]; +} + +//by marshmellow +//countFC is to detect the field clock lengths. +//counts and returns the 2 most common wave lengths +uint16_t countFC(uint8_t *BitStream, size_t size) +{ + uint8_t fcLens[] = {0,0,0,0,0,0,0,0,0,0}; + uint16_t fcCnts[] = {0,0,0,0,0,0,0,0,0,0}; + uint8_t fcLensFnd = 0; + uint8_t lastFCcnt=0; + uint32_t fcCounter = 0; + size_t i; + + // prime i to first up transition + for (i = 1; i < size-1; i++) + if (BitStream[i] > BitStream[i-1] && BitStream[i] >= BitStream[i+1]) + break; + + for (; i < size-1; i++){ + if (BitStream[i] > BitStream[i-1] && BitStream[i] >= BitStream[i+1]){ + // new up transition + fcCounter++; + + //if we had 5 and now have 9 then go back to 8 (for when we get a fc 9 instead of an 8) + if (lastFCcnt==5 && fcCounter==9) fcCounter--; + //if odd and not rc/5 add one (for when we get a fc 9 instead of 10) + if ((fcCounter==9 && fcCounter & 1) || fcCounter==4) fcCounter++; + + // save last field clock count (fc/xx) + // find which fcLens to save it to: + for (int ii=0; ii<10; ii++){ + if (fcLens[ii]==fcCounter){ + fcCnts[ii]++; + fcCounter=0; + break; + } + } + if (fcCounter>0 && fcLensFnd<10){ + //add new fc length + fcCnts[fcLensFnd]++; + fcLens[fcLensFnd++]=fcCounter; + } + fcCounter=0; + } else { + // count sample + fcCounter++; + } + } + + uint8_t best1=9, best2=9, best3=9; + uint16_t maxCnt1=0; + // go through fclens and find which ones are bigest 2 + for (i=0; i<10; i++){ + // PrintAndLog("DEBUG: FC %d, Cnt %d, Errs %d",fcLens[i],fcCnts[i],errCnt); + // get the 3 best FC values + if (fcCnts[i]>maxCnt1) { + best3=best2; + best2=best1; + maxCnt1=fcCnts[i]; + best1=i; + } else if(fcCnts[i]>fcCnts[best2]){ + best3=best2; + best2=i; + } else if(fcCnts[i]>fcCnts[best3]){ + best3=i; + } + } + uint8_t fcH=0, fcL=0; + if (fcLens[best1]>fcLens[best2]){ + fcH=fcLens[best1]; + fcL=fcLens[best2]; + } else{ + fcH=fcLens[best2]; + fcL=fcLens[best1]; + } + + // TODO: take top 3 answers and compare to known Field clocks to get top 2 + + uint16_t fcs = (((uint16_t)fcH)<<8) | fcL; + // PrintAndLog("DEBUG: Best %d best2 %d best3 %d",fcLens[best1],fcLens[best2],fcLens[best3]); + + return fcs; +}