return num;
}
+//by marshmellow
+// search for given preamble in given BitStream and return success=1 or fail=0 and startIndex (where it was found)
+bool preambleSearch(uint8_t *BitStream, uint8_t *preamble, size_t pLen, size_t *size, size_t *startIdx){
+ return preambleSearchEx(BitStream, preamble, pLen, size, startIdx, false);
+}
//by marshmellow
//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)
+// param @findone: look for a repeating preamble or only the first.
+// em4x05/4x69 only sends preamble once, so look for it once in the first pLen bits
+bool preambleSearchEx(uint8_t *BitStream, uint8_t *preamble, size_t pLen, size_t *size, size_t *startIdx, bool findone)
{
// Sanity check. If preamble length is bigger than bitstream length.
- if ( *size <= pLen ) return 0;
+ if ( *size <= pLen ) return false;
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);
//first index found
foundCnt++;
if (foundCnt == 1){
*startIdx = idx;
+ if (findone) return true;
}
if (foundCnt == 2){
*size = idx - *startIdx;
- return 1;
+ return true;
}
}
}
- return 0;
+ return false;
+}
+
+// find start of modulating data (for fsk and psk) in case of beginning noise or slow chip startup.
+size_t findModStart(uint8_t dest[], size_t size, uint8_t threshold_value, uint8_t expWaveSize) {
+ size_t i = 0;
+ size_t waveSizeCnt = 0;
+ uint8_t thresholdCnt = 0;
+ bool isAboveThreshold = dest[i++] >= threshold_value;
+ for (; i < size-20; i++ ) {
+ if(dest[i] < threshold_value && isAboveThreshold) {
+ thresholdCnt++;
+ if (thresholdCnt > 2 && waveSizeCnt < expWaveSize+1) break;
+ isAboveThreshold = false;
+ waveSizeCnt = 0;
+ } else if (dest[i] >= threshold_value && !isAboveThreshold) {
+ thresholdCnt++;
+ if (thresholdCnt > 2 && waveSizeCnt < expWaveSize+1) break;
+ isAboveThreshold = true;
+ waveSizeCnt = 0;
+ } else {
+ waveSizeCnt++;
+ }
+ if (thresholdCnt > 10) break;
+ }
+ if (g_debugMode == 2) prnt("DEBUG: threshold Count reached at %u, count: %u",i, thresholdCnt);
+ return i;
}
//by marshmellow
//takes 1s and 0s and searches for EM410x format - output EM ID
-int Em410xDecode(uint8_t *BitStream, size_t *size, size_t *startIdx, uint32_t *hi, uint64_t *lo)
+// 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)
{
- //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
- uint32_t i = 0;
- if (BitStream[1]>1) return -1; //allow only 1s and 0s
-
- // 111111111 bit pattern represent start of frame
- // 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;
+ //allow only 1s and 0s
+ // only checking first bitvalue?!
+ if (BitStream[1] > 1) return 0;
+
+ uint32_t i = 0, idx = 0, parityBits = 0;
+ uint8_t fmtlen = 0;
*startIdx = 0;
- errChk = preambleSearch(BitStream, preamble, sizeof(preamble), size, startIdx);
- if (errChk == 0 ) return -4;
- if (*size < 64) return -3;
- if (*size > 64) FmtLen = 22;
- *startIdx += 1; //get rid of 0 from preamble
- idx = *startIdx + 9;
- for (i=0; i<FmtLen; i++){ //loop through 10 or 22 sets of 5 bits (50-10p = 40 bits or 88 bits)
- parityBits = bytebits_to_byte(BitStream+(i*5)+idx,5);
- //check even parity - quit if failed
- if (parityTest(parityBits, 5, 0) == 0) return -5;
+
+ // 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;
+
+ fmtlen = (*size > 64) ? 22 : 10;
+
+ idx = *startIdx + sizeof(preamble);
+
+ //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 ii=0; ii<4; ii++){
+ for (uint8_t j = 0; j < 4; j++){
*hi = (*hi << 1) | (*lo >> 63);
- *lo = (*lo << 1) | (BitStream[(i*5)+ii+idx]);
+ *lo = (*lo << 1) | (BitStream[(i*5) + j + idx]);
}
}
- if (errChk != 0) return 1;
//skip last 5 bit parity test for simplicity.
// *size = 64 | 128;
- return 0;
+ return 1;
}
//by marshmellow
size_t startIdx=0;
uint8_t preamble[] = {1,1,1,1,1,0};
- uint8_t errChk = preambleSearch(BitStream, preamble, sizeof(preamble), size, &startIdx);
- if (errChk == 0) return -3; //preamble not found
+ if (!preambleSearch(BitStream, preamble, sizeof(preamble), size, &startIdx))
+ return -3; //preamble not found
+
if (*size != 96) return -2; //should have found 96 bits
+
//check first 6 spacer bits to verify format
if (!BitStream[startIdx+5] && !BitStream[startIdx+10] && !BitStream[startIdx+15] && !BitStream[startIdx+20] && !BitStream[startIdx+25] && !BitStream[startIdx+30]){
//confirmed proper separator bits found
{
size_t last_transition = 0;
size_t idx = 1;
- //uint32_t maxVal=0;
if (fchigh==0) fchigh=10;
if (fclow==0) fclow=8;
//set the threshold close to 0 (graph) or 128 std to avoid static
size_t currSample = 0;
if ( size < 1024 ) return 0; // not enough samples
- // jump to modulating data by finding the first 4 threshold crossings (or first 2 waves)
- // in case you have junk or noise at the beginning of the trace...
- uint8_t thresholdCnt = 0;
- size_t waveSizeCnt = 0;
- bool isAboveThreshold = dest[idx++] >= threshold_value;
- for (; idx < size-20; idx++ ) {
- if(dest[idx] < threshold_value && isAboveThreshold) {
- thresholdCnt++;
- if (thresholdCnt > 2 && waveSizeCnt < fchigh+1) break;
- isAboveThreshold = false;
- waveSizeCnt = 0;
- } else if (dest[idx] >= threshold_value && !isAboveThreshold) {
- thresholdCnt++;
- if (thresholdCnt > 2 && waveSizeCnt < fchigh+1) break;
- isAboveThreshold = true;
- waveSizeCnt = 0;
- } else {
- waveSizeCnt++;
- }
- if (thresholdCnt > 10) break;
- }
- if (g_debugMode == 2) prnt("threshold Count reached at %u",idx);
+ //find start of modulating data in trace
+ idx = findModStart(dest, size, threshold_value, fchigh);
// Need to threshold first sample
if(dest[idx] < threshold_value) dest[0] = 0;
if (*size < 96*2) 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
+ if (!preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx))
+ return -3; //preamble not found
numStart = startIdx + sizeof(preamble);
// final loop, go over previously decoded FSK data and manchester decode into usable tag ID
// 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
+ if (preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx))
+ return -3; //preamble not found
numStart = startIdx + sizeof(preamble);
// final loop, go over previously decoded FSK data and manchester decode into usable tag ID
//Handle the data
size_t startIdx = 0;
uint8_t preamble[] = {0,0,0,0,0,0,0,0,0,1};
- uint8_t errChk = preambleSearch(dest, preamble, sizeof(preamble), &size, &startIdx);
- if (errChk == 0) return -4; //preamble not found
+ if (! preambleSearch(dest, preamble, sizeof(preamble), &size, &startIdx))
+ return -4; //preamble not found
if (!dest[startIdx+8] && dest[startIdx+17]==1 && dest[startIdx+26]==1 && dest[startIdx+35]==1 && dest[startIdx+44]==1 && dest[startIdx+53]==1){
//confirmed proper separator bits found
if (*size < 64*2) return -2;
size_t startIdx = 0;
uint8_t preamble[] = {1,1,1,1,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};
- uint8_t errChk = preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx);
- if (errChk == 0) return -4; //preamble not found
+ if (!preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx))
+ return -4; //preamble not found
+
uint32_t checkCalc = bytebits_to_byte(dest+startIdx,8) ^
bytebits_to_byte(dest+startIdx+8,8) ^
bytebits_to_byte(dest+startIdx+16,8) ^
if (*size < 96) return -1; //make sure buffer has data
size_t startIdx = 0;
uint8_t preamble[] = {0,1,0,1,0,1,1,0,0,1,0,0,1,0,0,1,0,1,0,1,0,0,1,1,0,0,1,1,0,0,1,0};
- uint8_t errChk = preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx);
- if (errChk == 0) return -2; //preamble not found
+ if (!preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx))
+ return -2; //preamble not found
if (*size != 96) return -3; //wrong demoded size
//return start position
return (int)startIdx;
if (*size < 96) return -1; //make sure buffer has data
size_t startIdx = 0;
uint8_t preamble[] = {1,0,1,1,1,0,1,1,0,0,0,0};
- uint8_t errChk = preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx);
- if (errChk == 0) return -2; //preamble not found
+ if (!preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx))
+ return -2; //preamble not found
if (*size != 96) return -3; //wrong demoded size
//return start position
return (int)startIdx;
if (*size < 128*2) return -1; //make sure buffer has data
size_t startIdx = 0;
uint8_t preamble[] = {0,0,0,1,0,0,0,0,1,1,0,1,0,0,0,0,0,0,0,0,0,0,0};
- uint8_t errChk = preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx);
- if (errChk == 0) return -2; //preamble not found
+ if (!preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx))
+ return -2; //preamble not found
if (*size != 128) return -3; //wrong demoded size
//return start position
return (int)startIdx;
if (*size < 128*2) return -1; //make sure buffer has enough data
size_t startIdx = 0;
uint8_t preamble[] = {0,0,0,0,0,0,0,0,0,0,1};
- uint8_t errChk = preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx);
- if (errChk == 0) return -2; //preamble not found
+ if (!preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx))
+ return -2; //preamble not found
if (*size != 128) return -3; //wrong demoded size
//return start position
return (int)startIdx;
if (*size < 64*2) return -1; //make sure buffer has enough data
size_t startIdx = 0;
uint8_t preamble[] = {1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,0};
- uint8_t errChk = preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx);
- if (errChk == 0) return -2; //preamble not found
+ if (!preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx))
+ return -2; //preamble not found
if (*size != 64) return -3; // wrong demoded size
uint8_t checkchksum = 0;
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 (!preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx))
+ return -4; //preamble not found
if (*size != 96) return -5;
return (int)startIdx;
}
// 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[] = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,1};
size_t startIdx = 0;
- uint8_t errChk = preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx);
- if (errChk == 0) return -4; //preamble not found
+ uint8_t preamble[] = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,1};
+ if (!preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx))
+ return -4; //preamble not found
if (*size != 128) return -3;
return (int)startIdx;
}
size_t startIdx = 0;
//uint8_t preamble[] = {1,1,1,1,1,1,1,1,1,0,0,0,1};
uint8_t preamble[] = {1,1,1,1,1,1,1,1,1,0};
- uint8_t errChk = preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx);
- if (errChk == 0) return -4; //preamble not found
+ if (!preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx))
+ return -4; //preamble not found
return (int) startIdx;
}
if (*size < 64*2) return -1;
size_t startIdx = 0;
uint8_t preamble[] = {0,1,0,0,1,0,0,1,0,1,0,0,0,1,0,0,0,1,0,1,0,1,0,0,0,1,0,0,1,0,1,1};
- uint8_t errChk = preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx);
- if (errChk == 0) return -2; //preamble not found
+ if (!preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx))
+ return -2; //preamble not found
if (*size != 64) return -3; // wrong demoded size
return (int) startIdx;
}
continue;
// else new peak
// if we got less than the small fc + tolerance then set it to the small fc
- if (fcCounter < fcLow+fcTol)
+ // if it is inbetween set it to the last counter
+ if (fcCounter < fcHigh && fcCounter > fcLow)
+ fcCounter = lastFCcnt;
+ else if (fcCounter < fcLow+fcTol)
fcCounter = fcLow;
else //set it to the large fc
fcCounter = fcHigh;
}
}
- if (ii<0) return 0; // oops we went too far
+ if (ii<2) return 0; // oops we went too far
return clk[ii];
}
size_t numBits=0;
uint8_t curPhase = *invert;
size_t i=0, waveStart=1, waveEnd=0, firstFullWave=0, lastClkBit=0;
- uint8_t fc=0, fullWaveLen=0, tol=1;
- uint16_t errCnt=0, waveLenCnt=0;
- fc = countFC(dest, *size, 0);
+ uint16_t fc=0, fullWaveLen=0, tol=1;
+ uint16_t errCnt=0, waveLenCnt=0, errCnt2=0;
+ fc = countFC(dest, *size, 1);
+ uint8_t fc2 = fc >> 8;
+ if (fc2 == 10) return -1; //fsk found - quit
+ fc = fc & 0xFF;
if (fc!=2 && fc!=4 && fc!=8) return -1;
//prnt("DEBUG: FC: %d",fc);
*clock = DetectPSKClock(dest, *size, *clock);
if (*clock == 0) return -1;
- // jump to modulating data by finding the first 2 threshold crossings (or first 1 waves)
- // in case you have junk or noise at the beginning of the trace...
- uint8_t thresholdCnt = 0;
- size_t waveSizeCnt = 0;
- uint8_t threshold_value = 123; //-5
- bool isAboveThreshold = dest[i++] >= threshold_value;
- for (; i < *size-20; i++ ) {
- if(dest[i] < threshold_value && isAboveThreshold) {
- thresholdCnt++;
- if (thresholdCnt > 2 && waveSizeCnt < fc+1) break;
- isAboveThreshold = false;
- waveSizeCnt = 0;
- } else if (dest[i] >= threshold_value && !isAboveThreshold) {
- thresholdCnt++;
- if (thresholdCnt > 2 && waveSizeCnt < fc+1) break;
- isAboveThreshold = true;
- waveSizeCnt = 0;
- } else {
- waveSizeCnt++;
- }
- if (thresholdCnt > 10) break;
- }
- if (g_debugMode == 2) prnt("DEBUG PSK: threshold Count reached at %u, count: %u",i, thresholdCnt);
+ //find start of modulating data in trace
+ uint8_t threshold_value = 123; //-5
+ i = findModStart(dest, *size, threshold_value, fc);
- int avgWaveVal=0, lastAvgWaveVal=0;
- waveStart = i+1;
//find first phase shift
+ int avgWaveVal=0, lastAvgWaveVal=0;
+ waveStart = i;
for (; i<loopCnt; i++){
+ // find peak
if (dest[i]+fc < dest[i+1] && dest[i+1] >= dest[i+2]){
waveEnd = i+1;
if (g_debugMode == 2) prnt("DEBUG PSK: waveEnd: %u, waveStart: %u",waveEnd, waveStart);
lastAvgWaveVal = avgWaveVal/(waveLenCnt);
firstFullWave = waveStart;
fullWaveLen=waveLenCnt;
- //if average wave value is > graph 0 then it is an up wave or a 1
- if (lastAvgWaveVal > threshold_value) curPhase ^= 1; //fudge graph 0 a little 123 vs 128
+ //if average wave value is > graph 0 then it is an up wave or a 1 (could cause inverting)
+ if (lastAvgWaveVal > threshold_value) curPhase ^= 1;
break;
}
waveStart = i+1;
//set start of wave as clock align
lastClkBit = firstFullWave;
if (g_debugMode==2) prnt("DEBUG PSK: firstFullWave: %u, waveLen: %u",firstFullWave,fullWaveLen);
- if (g_debugMode==2) prnt("DEBUG: clk: %d, lastClkBit: %u, fc: %u", *clock, lastClkBit,(unsigned int) fc);
+ if (g_debugMode==2) prnt("DEBUG PSK: clk: %d, lastClkBit: %u, fc: %u", *clock, lastClkBit,(unsigned int) fc);
waveStart = 0;
dest[numBits++] = curPhase; //set first read bit
for (i = firstFullWave + fullWaveLen - 1; i < *size-3; i++){
} else if (i+1 > lastClkBit + *clock + tol + fc){
lastClkBit += *clock; //no phase shift but clock bit
dest[numBits++] = curPhase;
+ } else if (waveLenCnt < fc - 1) { //wave is smaller than field clock (shouldn't happen often)
+ errCnt2++;
+ if(errCnt2 > 101) return errCnt2;
}
avgWaveVal = 0;
waveStart = i+1;
projects / proxmark3-svn / commitdiff