parityWd = (parityWd << 1) | BitStream[startIdx+word+bit];
BitStream[j++] = (BitStream[startIdx+word+bit]);
}
- if (word+pLen >= bLen) break;
+ if (word+pLen > bLen) break;
j--; // overwrite parity with next data
// if parity fails then return 0
uint8_t foundCnt = 0;
for (int idx = 0; idx < *size - pLen; idx++){
if (memcmp(BitStream+idx, preamble, pLen) == 0){
- if (g_debugMode) prnt("DEBUG: preamble found at %u", idx);
+ if (g_debugMode) prnt("DEBUG: preamble found at %i", idx);
//first index found
foundCnt++;
if (foundCnt == 1){
//by marshmellow
//takes 1s and 0s and searches for EM410x format - output EM ID
// actually, no arguments needed - built this way in case we want this to be a direct call from "data " cmds in the future
-uint8_t Em410xDecode(uint8_t *BitStream, size_t *size, size_t *startIdx, uint32_t *hi, uint64_t *lo)
+int Em410xDecode(uint8_t *BitStream, size_t *size, size_t *startIdx, uint32_t *hi, uint64_t *lo)
{
- //allow only 1s and 0s
- // only checking first bitvalue?!
- if (BitStream[1] > 1) return 0;
+ // sanity check
+ if (*size < 64) return -3;
+ if (BitStream[1] > 1) return -1;
- uint32_t i = 0, idx = 0, parityBits = 0;
- uint8_t fmtlen = 0;
+ uint8_t fmtlen;
*startIdx = 0;
// preamble 0111111111
// include 0 in front to help get start pos
uint8_t preamble[] = {0,1,1,1,1,1,1,1,1,1};
- if (!preambleSearch(BitStream, preamble, sizeof(preamble), size, startIdx))
- return 0;
- if (*size < 64) return 0;
+ if (!preambleSearch(BitStream, preamble, sizeof(preamble), size, startIdx))
+ return -2;
+
+ //XL and normal size.
+ if (*size != 64 && *size != 128) return -3;
- fmtlen = (*size > 64) ? 22 : 10;
+ fmtlen = (*size == 128) ? 22 : 10;
- idx = *startIdx + sizeof(preamble);
+ //skip last 4bit parity row for simplicity
+ *size = removeParity(BitStream, *startIdx + sizeof(preamble), 5, 0, fmtlen * 5);
- //loop through 10 or 22 sets of 5 bits (50-10p = 40 bits or 88 bits)
- for (i=0; i < fmtlen; i++){
- parityBits = bytebits_to_byte(BitStream + (i*5) + idx, 5);
- //check even parity
- if (parityTest(parityBits, 5, 0) == 0) return 0;
- //set uint64 with ID from BitStream
- for (uint8_t j = 0; j < 4; j++){
- *hi = (*hi << 1) | (*lo >> 63);
- *lo = (*lo << 1) | (BitStream[(i*5) + j + idx]);
- }
+ switch (*size) {
+ case 40: {
+ // std em410x format
+ *hi = 0;
+ *lo = ((uint64_t)(bytebits_to_byte(BitStream, 8)) << 32) | (bytebits_to_byte(BitStream + 8, 32));
+ break;
+ }
+ case 88: {
+ // long em format
+ *hi = (bytebits_to_byte(BitStream, 24));
+ *lo = ((uint64_t)(bytebits_to_byte(BitStream + 24, 32)) << 32) | (bytebits_to_byte(BitStream + 24 + 32, 32));
+ break;
+ }
+ default: return -4;
}
- //skip last 5 bit parity test for simplicity.
- // *size = 64 | 128;
return 1;
}
//by marshmellow
//demodulates strong heavily clipped samples
+//RETURN: num of errors. if 0, is ok.
int cleanAskRawDemod(uint8_t *BinStream, size_t *size, int clk, int invert, int high, int low)
{
size_t bitCnt=0, smplCnt=0, errCnt=0;
//by marshmellow
//take 10 and 01 and manchester decode
//run through 2 times and take least errCnt
-int manrawdecode(uint8_t * BitStream, size_t *size, uint8_t invert){
+int manrawdecode(uint8_t *BitStream, size_t *size, uint8_t invert){
+
+ // sanity check
+ if (*size < 16) return -1;
+
int errCnt = 0, bestErr = 1000;
uint16_t bitnum = 0, MaxBits = 512, bestRun = 0;
size_t i, k;
- if (*size < 16) return -1;
+
//find correct start position [alignment]
- for (k=0; k < 2; ++k){
- for (i=k; i<*size-3; i += 2)
+ for (k = 0; k < 2; ++k){
+ for (i = k; i < *size-3; i += 2) {
if (BitStream[i] == BitStream[i+1])
errCnt++;
-
+ }
if (bestErr > errCnt){
bestErr = errCnt;
bestRun = k;
}
- errCnt=0;
+ errCnt = 0;
}
+
//decode
- for (i=bestRun; i < *size-3; i += 2){
+ for (i = bestRun; i < *size-3; i += 2){
if (BitStream[i] == 1 && (BitStream[i+1] == 0)){
BitStream[bitnum++] = invert;
} else if ((BitStream[i] == 0) && BitStream[i+1] == 1){
} else {
BitStream[bitnum++] = 7;
}
- if (bitnum>MaxBits) break;
+ if (bitnum > MaxBits) break;
}
- *size=bitnum;
+ *size = bitnum;
return bestErr;
}
}
return 0;
}
+void SetGraphClock( int clock, int startidx){
+ PlotClock = clock;
+ PlockClockStartIndex = startidx;
+}
// by marshmellow
// not perfect especially with lower clocks or VERY good antennas (heavy wave clipping)
// return start index of best starting position for that clock and return clock (by reference)
int DetectASKClock(uint8_t dest[], size_t size, int *clock, int maxErr)
{
- size_t i=1;
+ size_t i = 1;
uint8_t clk[] = {255,8,16,32,40,50,64,100,128,255};
uint8_t clkEnd = 9;
uint8_t loopCnt = 255; //don't need to loop through entire array...
- if (size <= loopCnt+60) return -1; //not enough samples
+ if (size <= loopCnt + 60) return -1; //not enough samples
size -= 60; //sometimes there is a strange end wave - filter out this....
//if we already have a valid clock
- uint8_t clockFnd=0;
- for (;i<clkEnd;++i)
+ uint8_t clockFnd = 0;
+ for (; i < clkEnd; ++i)
if (clk[i] == *clock) clockFnd = i;
//clock found but continue to find best startpos
size_t errCnt = 0;
size_t arrLoc, loopEnd;
- if (clockFnd>0) {
+ if (clockFnd > 0) {
clkCnt = clockFnd;
clkEnd = clockFnd+1;
} else {
- clkCnt=1;
+ clkCnt = 1;
}
//test each valid clock from smallest to greatest to see which lines up
- for(; clkCnt < clkEnd; clkCnt++) {
+ for (; clkCnt < clkEnd; clkCnt++) {
if (clk[clkCnt] <= 32) {
tol=1;
} else {
if (g_debugMode == 2) prnt("DEBUG ASK: clk %d, err %d, startpos %d, endpos %d", clk[clkCnt], errCnt, ii, i);
if (errCnt==0 && clkCnt<7) {
if (!clockFnd) *clock = clk[clkCnt];
+
+ SetGraphClock(*clock, ii);
return ii;
}
//if we found errors see if it is lowest so far and save it as best run
if (g_debugMode == 2) prnt("DEBUG ASK: clk %d, # Errors %d, Current Best Clk %d, bestStart %d", clk[k], bestErr[k], clk[best], bestStart[best]);
}
if (!clockFnd) *clock = clk[best];
+
+ SetGraphClock(*clock, bestStart[best]);
return bestStart[best];
}
// a phase shift is determined by measuring the sample length of each wave
int DetectPSKClock(uint8_t dest[], size_t size, int clock)
{
- uint8_t clk[]={255,16,32,40,50,64,100,128,255}; //255 is not a valid clock
+ uint8_t clk[] = {255,16,32,40,50,64,100,128,255}; //255 is not a valid clock
uint16_t loopCnt = 4096; //don't need to loop through entire array...
- if (size == 0) return 0;
- if (size<loopCnt) loopCnt = size-20;
//if we already have a valid clock quit
size_t i=1;
for (; i < 8; ++i)
if (clk[i] == clock) return clock;
+
+ if (size < 160+20) return 0;
+
+ // size must be larger than 20 here, and 160 later on.
+ if (size < loopCnt) loopCnt = size-20;
size_t waveStart=0, waveEnd=0, firstFullWave=0, lastClkBit=0;
uint8_t clkCnt, fc=0, fullWaveLen=0, tol=1;
uint16_t peakcnt=0, errCnt=0, waveLenCnt=0;
- uint16_t bestErr[]={1000,1000,1000,1000,1000,1000,1000,1000,1000};
- uint16_t peaksdet[]={0,0,0,0,0,0,0,0,0};
+ uint16_t bestErr[] = {1000,1000,1000,1000,1000,1000,1000,1000,1000};
+ uint16_t peaksdet[] = {0,0,0,0,0,0,0,0,0};
fc = countFC(dest, size, 0);
if (fc!=2 && fc!=4 && fc!=8) return -1;
if (g_debugMode==2) prnt("DEBUG PSK: FC: %d",fc);
//find first full wave
- for (i=160; i<loopCnt; i++){
+ for (i=160; i < loopCnt; i++){
if (dest[i] < dest[i+1] && dest[i+1] >= dest[i+2]){
if (waveStart == 0) {
waveStart = i+1;
}
}
}
- if (g_debugMode ==2) prnt("DEBUG PSK: firstFullWave: %d, waveLen: %d",firstFullWave,fullWaveLen);
+ if (g_debugMode == 2) prnt("DEBUG PSK: firstFullWave: %d, waveLen: %d",firstFullWave,fullWaveLen);
//test each valid clock from greatest to smallest to see which lines up
- for(clkCnt=7; clkCnt >= 1 ; clkCnt--){
+ for (clkCnt=7; clkCnt >= 1 ; clkCnt--){
lastClkBit = firstFullWave; //set end of wave as clock align
waveStart = 0;
errCnt=0;
}
}
}
- if (errCnt == 0){
- return clk[clkCnt];
- }
- if (errCnt <= bestErr[clkCnt]) bestErr[clkCnt]=errCnt;
- if (peakcnt > peaksdet[clkCnt]) peaksdet[clkCnt]=peakcnt;
+ if (errCnt == 0) return clk[clkCnt];
+ if (errCnt <= bestErr[clkCnt]) bestErr[clkCnt] = errCnt;
+ if (peakcnt > peaksdet[clkCnt]) peaksdet[clkCnt] = peakcnt;
}
//all tested with errors
//return the highest clk with the most peaks found
- uint8_t best=7;
- for (i=7; i>=1; i--){
- if (peaksdet[i] > peaksdet[best]) {
+ uint8_t best = 7;
+ for (i=7; i >= 1; i--){
+ if (peaksdet[i] > peaksdet[best])
best = i;
- }
+
if (g_debugMode == 2) prnt("DEBUG PSK: Clk: %d, peaks: %d, errs: %d, bestClk: %d",clk[i],peaksdet[i],bestErr[i],clk[best]);
}
return clk[best];
//by marshmellow
//detect nrz clock by reading #peaks vs no peaks(or errors)
+//iceman: shouldn't param clock be reference? like DetectASKClock
int DetectNRZClock(uint8_t dest[], size_t size, int clock)
{
- size_t i=0;
- uint8_t clk[]={8,16,32,40,50,64,100,128,255};
+ size_t i = 0;
+ uint8_t clk[] = {8,16,32,40,50,64,100,128,255};
size_t loopCnt = 4096; //don't need to loop through entire array...
- if (size == 0) return 0;
- if (size<loopCnt) loopCnt = size-20;
+
//if we already have a valid clock quit
for (; i < 8; ++i)
if (clk[i] == clock) return clock;
+
+ if (size < 20) return 0;
+ // size must be larger than 20 here
+ if (size < loopCnt) loopCnt = size-20;
//get high and low peak
int peak, low;
if (!firstpeak) continue;
smplCnt++;
} else {
- firstpeak=true;
+ firstpeak = true;
if (smplCnt > 6 ){
if (maxPeak > smplCnt){
maxPeak = smplCnt;
}
peakcnt++;
//prnt("maxPk: %d, smplCnt: %d, peakcnt: %d",maxPeak,smplCnt,peakcnt);
- smplCnt=0;
+ smplCnt = 0;
}
}
}
uint8_t ignoreWindow = 4;
bool lastPeakHigh = 0;
int lastBit = 0;
- peakcnt=0;
+ peakcnt = 0;
//test each valid clock from smallest to greatest to see which lines up
for(clkCnt=0; clkCnt < 8; ++clkCnt){
//ignore clocks smaller than smallest peak
if (dest[i] >= peak || dest[i] <= low) {
//if same peak don't count it
if ((dest[i] >= peak && !lastPeakHigh) || (dest[i] <= low && lastPeakHigh)) {
- peakcnt++;
+ peakcnt++;
}
lastPeakHigh = (dest[i] >= peak);
bitHigh = true;
}
//else if not a clock bit and no peaks
} else if (dest[i] < peak && dest[i] > low){
- if (ignoreCnt==0){
+ if (ignoreCnt == 0){
bitHigh=false;
- if (errBitHigh==true) peakcnt--;
+ if (errBitHigh==true)
+ peakcnt--;
errBitHigh=false;
} else {
ignoreCnt--;
errBitHigh=true;
}
}
- if(peakcnt>peaksdet[clkCnt]) {
- peaksdet[clkCnt]=peakcnt;
+ if (peakcnt > peaksdet[clkCnt]) {
+ peaksdet[clkCnt] = peakcnt;
}
}
}
}
- int iii=7;
- uint8_t best=0;
- for (iii=7; iii > 0; iii--){
- if ((peaksdet[iii] >= (peaksdet[best]-1)) && (peaksdet[iii] <= peaksdet[best]+1) && lowestTransition) {
- if (clk[iii] > (lowestTransition - (clk[iii]/8)) && clk[iii] < (lowestTransition + (clk[iii]/8))) {
- best = iii;
- }
- } else if (peaksdet[iii] > peaksdet[best]){
- best = iii;
+
+ uint8_t best = 0;
+ for (int m = 7; m > 0; m--){
+ if ((peaksdet[m] >= (peaksdet[best]-1)) && (peaksdet[m] <= peaksdet[best]+1) && lowestTransition) {
+ if (clk[m] > (lowestTransition - (clk[m]/8)) && clk[m] < (lowestTransition + (clk[m]/8))) {
+ best = m;
+ }
+ } else if (peaksdet[m] > peaksdet[best]){
+ best = m;
}
- if (g_debugMode==2) prnt("DEBUG NRZ: Clk: %d, peaks: %d, maxPeak: %d, bestClk: %d, lowestTrs: %d",clk[iii],peaksdet[iii],maxPeak, clk[best], lowestTransition);
+ if (g_debugMode==2) prnt("DEBUG NRZ: Clk: %d, peaks: %d, maxPeak: %d, bestClk: %d, lowestTrs: %d", clk[m], peaksdet[m], maxPeak, clk[best], lowestTransition);
}
return clk[best];
return errCnt;
}
+bool DetectST(uint8_t buffer[], size_t *size, int *foundclock) {
+ size_t ststart = 0, stend = 0;
+ return DetectST_ext(buffer, size, foundclock, &ststart, &stend);
+}
+
//by marshmellow
//attempt to identify a Sequence Terminator in ASK modulated raw wave
-bool DetectST(uint8_t buffer[], size_t *size, int *foundclock) {
+bool DetectST_ext(uint8_t buffer[], size_t *size, int *foundclock, size_t *ststart, size_t *stend) {
size_t bufsize = *size;
//need to loop through all samples and identify our clock, look for the ST pattern
uint8_t fndClk[] = {8,16,32,40,50,64,128};
size_t newloc = 0;
i=0;
if (g_debugMode==2) prnt("DEBUG STT: Starting STT trim - start: %d, datalen: %d ",dataloc, datalen);
-
+ bool firstrun = true;
// warning - overwriting buffer given with raw wave data with ST removed...
while ( dataloc < bufsize-(clk/2) ) {
//compensate for long high at end of ST not being high due to signal loss... (and we cut out the start of wave high part)
for(i=0; i < clk/2-tol; ++i) {
buffer[dataloc+i] = high+5;
}
+ } //test for single sample outlier (high between two lows) in the case of very strong waves
+ if (buffer[dataloc] >= high && buffer[dataloc+2] <= low) {
+ buffer[dataloc] = buffer[dataloc+2];
+ buffer[dataloc+1] = buffer[dataloc+2];
+ }
+ if (firstrun) {
+ *stend = dataloc;
+ *ststart = dataloc-(clk*4);
+ firstrun=false;
}
for (i=0; i<datalen; ++i) {
if (i+newloc < bufsize) {
projects / proxmark3-svn / blobdiff