- //fudge high/low bars by 25%
- high = (uint8_t)((((int)(high)-128)*.75)+128);
- low = (uint8_t)((((int)(low)-128)*.80)+128);
-
- //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=2; //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;
- uint8_t errCnt =0;
- uint32_t bestStart = *bitLen;
- uint32_t maxErr = (*bitLen/1000);
- uint32_t bestErrCnt = maxErr;
- //uint8_t midBit=0;
- uint8_t curBit=0;
- uint8_t bitHigh=0;
- uint8_t ignorewin=*clk/8;
- //PrintAndLog("DEBUG - lastbit - %d",lastBit);
- //loop to find first wave that works - align to clock
- for (iii=0; iii < gLen; ++iii){
- if ((dest[iii]>=high)||(dest[iii]<=low)){
- lastBit=iii-*clk;
- //loop through to see if this start location works
- for (i = iii; i < *bitLen; ++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;
- ignorewin=*clk/8;
- //curBit=*invert;
- //dest[bitnum]=curBit;
- 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
- //dest[bitnum]=curBit;
- 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) && (i<lastBit+*clk-tol || i>lastBit+*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 (bestStart == iii) break; //if current run == bestErrCnt run (after exhausted testing) then 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 < *bitLen; ++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]<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;
- 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) && ((i<lastBit+*clk-tol) || (i>lastBit+*clk+tol)) && (bitHigh==0)){
- //error bar found no clock...
- bitHigh=1;
- dest[bitnum]=77;
- bitnum++;
- errCnt++;
- }
- if (bitnum >=1000) break;
- }
- *bitLen=bitnum;
- } else{
- *bitLen=bitnum;
- *clk=bestStart;
- return -1;
- }
-
- if (bitnum>16){
- *bitLen=bitnum;
- } else return -1;
- return errCnt;
+ if (start == *size - 250 + 1) {
+ // did not find start sequence
+ return -1;
+ }
+ // Inverting signal if needed
+ if (first == 1) {
+ for (i = start; i < *size; i++) {
+ bitStream[i] = !bitStream[i];
+ }
+ *invert = 1;
+ }else *invert=0;
+
+ int iii;
+ //found start once now test length by finding next one
+ for (ii=start+29; ii <= *size - 250; ii++) {
+ first2 = bitStream[ii];
+ for (iii = ii; iii < ii + long_wait; iii++) {
+ if (bitStream[iii] != first2) {
+ break;
+ }
+ }
+ if (iii == (ii + long_wait)) {
+ break;
+ }
+ }
+ if (ii== *size - 250 + 1){
+ // did not find second start sequence
+ return -2;
+ }
+ bitCnt=ii-start;
+
+ // Dumping UID
+ i = start;
+ for (ii = 0; ii < bitCnt; ii++) {
+ bitStream[ii] = bitStream[i++];
+ }
+ *size=bitCnt;
+ return 1;
+}
+
+// by marshmellow - demodulate NRZ wave (both similar enough)
+// peaks invert bit (high=1 low=0) each clock cycle = 1 bit determined by last peak
+// there probably is a much simpler way to do this....
+int nrzRawDemod(uint8_t *dest, size_t *size, int *clk, int *invert, int maxErr)
+{
+ if (justNoise(dest, *size)) return -1;
+ *clk = DetectNRZClock(dest, *size, *clk);
+ if (*clk==0) return -2;
+ size_t i, 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
+ size_t iii = 0, bitnum = 0; //bitnum counter
+ uint16_t errCnt = 0, MaxBits = 1000;
+ size_t bestErrCnt = maxErr+1;
+ size_t bestPeakCnt = 0, bestPeakStart = 0;
+ uint8_t bestFirstPeakHigh=0, firstPeakHigh=0, curBit=0, bitHigh=0, errBitHigh=0;
+ 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
+ uint16_t peakCnt=0;
+ uint8_t ignoreWindow=4;
+ uint8_t ignoreCnt=ignoreWindow; //in case of noise near peak
+ //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;
+ //loop through to see if this start location works
+ for (i = iii; i < *size; ++i) {
+ // if we are at a clock bit
+ if ((i >= lastBit + *clk - tol) && (i <= lastBit + *clk + tol)) {
+ //test high/low
+ if (dest[i] >= high || dest[i] <= low) {
+ bitHigh = 1;
+ peakCnt++;
+ errBitHigh = 0;
+ ignoreCnt = ignoreWindow;
+ lastBit += *clk;
+ } else if (i == lastBit + *clk + tol) {
+ lastBit += *clk;
+ }
+ //else if no bars found
+ } else if (dest[i] < high && dest[i] > low){
+ if (ignoreCnt==0){
+ bitHigh=0;
+ if (errBitHigh==1) errCnt++;
+ errBitHigh=0;
+ } else {
+ ignoreCnt--;
+ }
+ } else if ((dest[i]>=high || dest[i]<=low) && (bitHigh==0)) {
+ //error bar found no clock...
+ errBitHigh=1;
+ }
+ if (((i-iii) / *clk)>=MaxBits) break;
+ }
+ //we got more than 64 good bits and not all errors
+ if (((i-iii) / *clk) > 64 && (errCnt <= (maxErr))) {
+ //possible good read
+ if (!errCnt || peakCnt > bestPeakCnt){
+ bestFirstPeakHigh=firstPeakHigh;
+ bestErrCnt = errCnt;
+ bestPeakCnt = peakCnt;
+ bestPeakStart = iii;
+ if (!errCnt) break; //great read - finish
+ }
+ }
+ }
+ }
+ //PrintAndLog("DEBUG: bestErrCnt: %d, maxErr: %d, bestStart: %d, bestPeakCnt: %d, bestPeakStart: %d",bestErrCnt,maxErr,bestStart,bestPeakCnt,bestPeakStart);
+ if (bestErrCnt > maxErr) return bestErrCnt;
+
+ //best run is good enough set to best run and set overwrite BinStream
+ lastBit = bestPeakStart - *clk;
+ memset(dest, bestFirstPeakHigh^1, bestPeakStart / *clk);
+ bitnum += (bestPeakStart / *clk);
+ for (i = bestPeakStart; i < *size; ++i) {
+ // if expecting a clock bit
+ if ((i >= lastBit + *clk - tol) && (i <= lastBit + *clk + tol)) {
+ // test high/low
+ if (dest[i] >= high || dest[i] <= low) {
+ peakCnt++;
+ bitHigh = 1;
+ errBitHigh = 0;
+ ignoreCnt = ignoreWindow;
+ curBit = *invert;
+ if (dest[i] >= high) curBit ^= 1;
+ dest[bitnum++] = curBit;
+ lastBit += *clk;
+ //else no bars found in clock area
+ } else if (i == lastBit + *clk + tol) {
+ dest[bitnum++] = curBit;
+ lastBit += *clk;
+ }
+ //else if no bars found
+ } else if (dest[i] < high && dest[i] > low){
+ if (ignoreCnt == 0){
+ bitHigh = 0;
+ if (errBitHigh == 1){
+ dest[bitnum++] = 7;
+ errCnt++;
+ }
+ errBitHigh=0;
+ } else {
+ ignoreCnt--;
+ }
+ } else if ((dest[i] >= high || dest[i] <= low) && (bitHigh == 0)) {
+ //error bar found no clock...
+ errBitHigh=1;
+ }
+ if (bitnum >= MaxBits) break;
+ }
+ *size = bitnum;
+ return bestErrCnt;
+}
+
+//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;
+ uint16_t fcCounter = 0;
+ uint16_t rfCounter = 0;
+ uint8_t firstBitFnd = 0;
+ size_t i;
+ if (size == 0) return 0;
+
+ 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++){
+ fcCounter++;
+ rfCounter++;
+
+ if (BitStream[i] <= BitStream[i-1] || BitStream[i] < BitStream[i+1])
+ continue;
+ // else new peak
+ // 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 ((fcCounter < lastFCcnt || fcCounter > lastFCcnt)){
+ //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;
+ }
+ 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];
projects / proxmark3-svn / blobdiff