//by marshmellow
//takes 1s and 0s and searches for EM410x format - output EM ID
-uint64_t Em410xDecode(uint8_t *BitStream, size_t size)
+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
uint32_t idx = 0;
uint32_t ii=0;
uint8_t resetCnt = 0;
- while( (idx + 64) < size) {
+ while( (idx + 64) < *size) {
restart:
// search for a start of frame marker
if ( memcmp(BitStream+idx, frame_marker_mask, sizeof(frame_marker_mask)) == 0)
{ // frame marker found
+ *startIdx=idx;
idx+=9;
for (i=0; i<10;i++){
for(ii=0; ii<5; ++ii){
parityTest ^= BitStream[(i*5)+ii+idx];
}
- if (!parityTest){
+ if (!parityTest){ //even parity
parityTest=0;
for (ii=0; ii<4;++ii){
lo=(lo<<1LL)|(BitStream[(i*5)+ii+idx]);
}
}
//skip last 5 bit parity test for simplicity.
+ *size = 64;
return lo;
}else{
idx++;
int askmandemod(uint8_t *BinStream, size_t *size, int *clk, int *invert)
{
int i;
+ int clk2=*clk;
*clk=DetectASKClock(BinStream, *size, *clk); //clock default
- if (*clk<8) *clk =64;
- if (*clk<32) *clk=32;
+ // 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;
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
+ 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;
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;
+ }
+ 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
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 BitStream[502] = {0};
//HACK: if clock not detected correctly - default
- if (*clk<8) *clk =64;
- if (*clk<32 && clk2==0) *clk=32;
+ 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;
for (i = iii; i < *size; ++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
//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++;
- //}
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;
- // bitnum=0;//start over
break;
}
}
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)
{
- size_t idx=0; //, found=0; //size=0,
+ size_t idx=0, size2=*size, startIdx=0;
// FSK demodulator
- size = fskdemod(dest, size,50,0,10,8);
+
+ *size = fskdemod(dest, size2,50,0,10,8);
// 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
int numshifts = 0;
idx = 0;
//one scan
- while( idx + sizeof(frame_marker_mask) < size) {
+ 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
+ startIdx=idx;
idx+=sizeof(frame_marker_mask);
- while(dest[idx] != dest[idx+1] && idx < size-2)
+ 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
idx += 2;
}
// Hopefully, we read a tag and hit upon the next frame marker
- if(idx + sizeof(frame_marker_mask) < size)
+ if(idx + sizeof(frame_marker_mask) < *size)
{
if ( memcmp(dest+idx, frame_marker_mask, sizeof(frame_marker_mask)) == 0)
{
//good return
- return idx;
+ *size=idx-startIdx;
+ return startIdx;
}
}
// reset
return -1;
}
+// loop to get raw paradox waveform then FSK demodulate the TAG ID from it
+size_t ParadoxdemodFSK(uint8_t *dest, size_t *size, uint32_t *hi2, uint32_t *hi, uint32_t *lo)
+{
+
+ size_t idx=0, size2=*size;
+ // FSK demodulator
+
+ *size = fskdemod(dest, size2,50,1,10,8);
+
+ // final loop, go over previously decoded manchester data and decode into usable tag ID
+ // 00001111 bit pattern represent start of frame, 01 pattern represents a 1 and 10 represents a 0
+ uint8_t frame_marker_mask[] = {0,0,0,0,1,1,1,1};
+ uint16_t 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
+ size2=idx;
+ 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)|1;
+ else // 0 1
+ *lo=(*lo<<1)|0;
+ numshifts++;
+ idx += 2;
+ }
+ // Hopefully, we read a tag and hit upon the next frame marker and got enough bits
+ if(idx + sizeof(frame_marker_mask) < *size && numshifts > 40)
+ {
+ if ( memcmp(dest+idx, frame_marker_mask, sizeof(frame_marker_mask)) == 0)
+ {
+ //good return - return start grid position and bits found
+ *size = ((numshifts*2)+8);
+ return size2;
+ }
+ }
+ // reset
+ *hi2 = *hi = *lo = 0;
+ numshifts = 0;
+ }else {
+ idx++;
+ }
+ }
+ return 0;
+}
+
uint32_t bytebits_to_byte(uint8_t* src, size_t numbits)
{
uint32_t num = 0;
// 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
-int parityTest(uint32_t bits, uint8_t bitLen, uint8_t pType)
+uint8_t parityTest(uint32_t bits, uint8_t bitLen, uint8_t pType)
{
uint8_t ans = 0;
- for (int i = 0; i < bitLen; i++){
+ for (uint8_t i = 0; i < bitLen; i++){
ans ^= ((bits >> i) & 1);
}
//PrintAndLog("DEBUG: ans: %d, ptype: %d",ans,pType);
int AWIDdemodFSK(uint8_t *dest, size_t size)
{
static const uint8_t THRESHOLD = 123;
- uint32_t idx=0;
+ uint32_t idx=0, idx2=0;
//make sure buffer has data
if (size < 96*50) return -1;
//test samples are not just noise
for( idx=0; idx < (size - 96); idx++) {
if ( memcmp(dest + idx, mask, sizeof(mask))==0) {
// frame marker found
- //return ID start index and size
- return idx;
- //size should always be 96
+ //return ID start index
+ if (idx2 == 0) idx2=idx;
+ else if(idx-idx2==96) return idx2;
+ else return -5;
+
+ // should always get 96 bits if it is awid
}
}
//never found mask
int PyramiddemodFSK(uint8_t *dest, size_t size)
{
static const uint8_t THRESHOLD = 123;
- uint32_t idx=0;
- // size_t size2 = size;
+ uint32_t idx=0, idx2=0;
+ // size_t size2 = size;
//make sure buffer has data
if (size < 128*50) return -5;
//test samples are not just noise
for( idx=0; idx < (size - 128); idx++) {
if ( memcmp(dest + idx, mask, sizeof(mask))==0) {
// frame marker found
- return idx;
+ if (idx2==0) idx2=idx;
+ else if (idx-idx2==128) return idx2;
+ else return -3;
}
}
//never found mask
// maybe somehow adjust peak trimming value based on samples to fix?
int DetectASKClock(uint8_t dest[], size_t size, int clock)
{
- int i=0;
- int clk[]={8,16,32,40,50,64,100,128,256};
- int loopCnt = 256; //don't need to loop through entire array...
- if (size<loopCnt) loopCnt = size;
+ int i=0;
+ int clk[]={8,16,32,40,50,64,100,128,256};
+ int loopCnt = 256; //don't need to loop through entire array...
+ if (size<loopCnt) loopCnt = size;
- //if we already have a valid clock quit
-
- for (;i<8;++i)
- if (clk[i] == clock) return clock;
+ //if we already have a valid clock quit
+
+ for (;i<8;++i)
+ if (clk[i] == clock) return clock;
- //get high and low peak
- int peak, low;
- getHiLo(dest, loopCnt, &peak, &low, 75, 75);
-
- int ii;
- int clkCnt;
- int tol = 0;
- int bestErr[]={1000,1000,1000,1000,1000,1000,1000,1000,1000};
- int errCnt=0;
- //test each valid clock from smallest to greatest to see which lines up
- for(clkCnt=0; clkCnt < 6; ++clkCnt){
- if (clk[clkCnt] == 32){
- tol=1;
- }else{
- tol=0;
- }
- 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/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{ //error no peak detected
- errCnt++;
- }
- }
- //if we found no errors this is correct one - return this clock
- if(errCnt==0) return clk[clkCnt];
- //if we found errors see if it is lowest so far and save it as best run
- if(errCnt<bestErr[clkCnt]) bestErr[clkCnt]=errCnt;
- }
- }
- }
- int iii=0;
- int best=0;
- for (iii=0; iii<8;++iii){
- if (bestErr[iii]<bestErr[best]){
- // current best bit to error ratio vs new bit to error ratio
- if (((size/clk[best])/bestErr[best] < (size/clk[iii])/bestErr[iii]) ){
- best = iii;
- }
- }
- }
- return clk[best];
+ //get high and low peak
+ int peak, low;
+ getHiLo(dest, loopCnt, &peak, &low, 75, 75);
+
+ int ii;
+ int clkCnt;
+ int tol = 0;
+ int bestErr[]={1000,1000,1000,1000,1000,1000,1000,1000,1000};
+ int errCnt=0;
+ //test each valid clock from smallest to greatest to see which lines up
+ for(clkCnt=0; clkCnt < 8; ++clkCnt){
+ if (clk[clkCnt] == 32){
+ tol=1;
+ }else{
+ tol=0;
+ }
+ 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{ //error no peak detected
+ errCnt++;
+ }
+ }
+ //if we found no errors then we can stop here
+ // this is correct one - return this clock
+ //PrintAndLog("DEBUG: clk %d, err %d, ii %d, i %d",clk[clkCnt],errCnt,ii,i);
+ if(errCnt==0 && clkCnt<6) return clk[clkCnt];
+ //if we found errors see if it is lowest so far and save it as best run
+ if(errCnt<bestErr[clkCnt]) bestErr[clkCnt]=errCnt;
+ }
+ }
+ }
+ uint8_t iii=0;
+ uint8_t best=0;
+ for (iii=0; iii<8; ++iii){
+ if (bestErr[iii]<bestErr[best]){
+ if (bestErr[iii]==0) bestErr[iii]=1;
+ // current best bit to error ratio vs new bit to error ratio
+ if (((size/clk[best])/bestErr[best] < (size/clk[iii])/bestErr[iii]) ){
+ best = iii;
+ }
+ }
+ }
+ return clk[best];
}
//by marshmellow
if (size<loopCnt) loopCnt = size;
//if we already have a valid clock quit
- for (; i < 8; ++i)
+ for (; i < 7; ++i)
if (clk[i] == clock) return clock;
//get high and low peak
uint8_t tol = 0;
int peakcnt=0;
int errCnt=0;
- int bestErr[]={1000,1000,1000,1000,1000,1000,1000,1000,1000};
- int peaksdet[]={0,0,0,0,0,0,0,0,0};
+ int bestErr[]={1000,1000,1000,1000,1000,1000,1000,1000};
+ int peaksdet[]={0,0,0,0,0,0,0,0};
//test each valid clock from smallest to greatest to see which lines up
- for(clkCnt=0; clkCnt < 6; ++clkCnt){
- if (clk[clkCnt] >= 32){
+ for(clkCnt=0; clkCnt < 7; ++clkCnt){
+ if (clk[clkCnt] <= 32){
tol=1;
}else{
tol=0;
errCnt=0;
peakcnt=0;
// now that we have the first one lined up test rest of wave array
- for (i=0; i < ((int)(size/clk[clkCnt])-1); ++i){
+ 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){
return clk[best];
}
-//by marshmellow (attempt to get rid of high immediately after a low)
+// by marshmellow (attempt to get rid of high immediately after a low)
void pskCleanWave(uint8_t *BitStream, size_t size)
{
int i;
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<size; i++){
+ if (lastBit!=BitStream[i]){
+ lastBit=BitStream[i];
+ BitStream[i]=1;
+ } else {
+ BitStream[i]=0;
+ }
+ }
+ return;
+}
-//redesigned by marshmellow adjusted from existing decode functions
-//indala id decoding - only tested on 26 bit tags, but attempted to make it work for more
+// redesigned by marshmellow adjusted from existing decode functions
+// indala id decoding - only tested on 26 bit tags, but attempted to make it work for more
int indala26decode(uint8_t *bitStream, size_t *size, uint8_t *invert)
{
//26 bit 40134 format (don't know other formats)
return 1;
}
-
-//by marshmellow - demodulate PSK1 wave or NRZ wave (both similar enough)
-//peaks switch bit (high=1 low=0) each clock cycle = 1 bit determined by last peak
+// by marshmellow - demodulate PSK1 wave or NRZ wave (both similar enough)
+// peaks invert bit (high=1 low=0) each clock cycle = 1 bit determined by last peak
int pskNRZrawDemod(uint8_t *dest, size_t *size, int *clk, int *invert)
{
pskCleanWave(dest,*size);
uint32_t bestStart = *size;
uint32_t maxErr = (*size/1000);
uint32_t bestErrCnt = maxErr;
- //uint8_t midBit=0;
uint8_t curBit=0;
uint8_t bitHigh=0;
uint8_t ignorewin=*clk/8;
return errCnt;
}
-
//by marshmellow
-//countFC is to detect the field clock and bit clock rates.
-//for fsk or ask not psk or nrz
-uint32_t countFC(uint8_t *BitStream, size_t size)
+//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)
{
- // get high/low thresholds
- int high, low;
- getHiLo(BitStream,10, &high, &low, 100, 100);
- // get zero crossing
- uint8_t zeroC = (high-low)/2+low;
- uint8_t clk[]={8,16,32,40,50,64,100,128};
- 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 rfLens[] = {0,0,0,0,0,0,0,0,0,0,0};
- // uint8_t rfCnts[] = {0,0,0,0,0,0,0,0,0,0};
- uint8_t fcLensFnd = 0;
+ 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 lastBit=0;
- uint8_t curBit=0;
uint8_t lastFCcnt=0;
- uint32_t errCnt=0;
uint32_t fcCounter = 0;
- uint32_t rfCounter = 0;
+ uint16_t rfCounter = 0;
uint8_t firstBitFnd = 0;
- int i;
-
+ 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; i++)
- if (BitStream[i]>=zeroC && BitStream[i-1]<zeroC)
+ for (i = 1; i < size-1; i++)
+ if (BitStream[i] > BitStream[i-1] && BitStream[i]>=BitStream[i+1])
break;
- for (; i < size; i++){
- curBit = BitStream[i];
- lastBit = BitStream[i-1];
- if (lastBit<zeroC && curBit >= zeroC){
- // new up transition
+ for (; i < size-1; i++){
+ if (BitStream[i] > BitStream[i-1] && BitStream[i]>=BitStream[i+1]){
+ // new peak
fcCounter++;
rfCounter++;
- if (fcCounter > 3 && fcCounter < 256){
- //we've counted enough that it could be a valid field clock
-
- //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++;
+ // 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<10; ii++){
- if (rfLens[ii]==rfCounter){
- //rfCnts[ii]++;
- rfCounter=0;
- break;
- }
- }
- if (rfCounter>0 && rfLensFnd<10){
- //PrintAndLog("DEBUG: rfCntr %d, fcCntr %d",rfCounter,fcCounter);
- //rfCnts[rfLensFnd]++;
- rfLens[rfLensFnd++]=rfCounter;
+ //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;
}
- } else {
- //PrintAndLog("DEBUG i: %d",i);
- firstBitFnd++;
}
- rfCounter=0;
- lastFCcnt=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 (rfCounter>0 && rfLensFnd<15){
+ //PrintAndLog("DEBUG: rfCntr %d, fcCntr %d",rfCounter,fcCounter);
+ rfCnts[rfLensFnd]++;
+ rfLens[rfLensFnd++]=rfCounter;
}
+ } else {
+ firstBitFnd++;
}
- if (fcCounter>0 && fcLensFnd<10){
- //add new fc length
- //PrintAndLog("FCCntr %d",fcCounter);
- fcCnts[fcLensFnd]++;
- fcLens[fcLensFnd++]=fcCounter;
- }
- } else{
- // hmmm this should not happen often - count them
- errCnt++;
+ rfCounter=0;
+ lastFCcnt=fcCounter;
}
- // reset counter
fcCounter=0;
} else {
// count sample
rfCounter++;
}
}
- // if too many errors return errors as negative number (IS THIS NEEDED?)
- if (errCnt>100) return -1*errCnt;
-
- uint8_t maxCnt1=0, best1=9, best2=9, best3=9, rfHighest=10, rfHighest2=10, rfHighest3=10;
+ uint8_t rfHighest=15, rfHighest2=15, rfHighest3=15;
- // go through fclens and find which ones are bigest 2
- for (i=0; i<10; i++){
- // PrintAndLog("DEBUG: FC %d, Cnt %d, Errs %d, RF %d",fcLens[i],fcCnts[i],errCnt,rfLens[i]);
-
- // 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;
- }
+ 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 (rfLens[i]>rfLens[rfHighest]){
+ if (rfCnts[i]>rfCnts[rfHighest]){
rfHighest3=rfHighest2;
rfHighest2=rfHighest;
rfHighest=i;
- } else if(rfLens[i]>rfLens[rfHighest2]){
+ } else if(rfCnts[i]>rfCnts[rfHighest2]){
rfHighest3=rfHighest2;
rfHighest2=i;
- } else if(rfLens[i]>rfLens[rfHighest3]){
+ } else if(rfCnts[i]>rfCnts[rfHighest3]){
rfHighest3=i;
}
- }
-
- // set allowed clock remainder tolerance to be 1 large field clock length
- // we could have mistakenly made a 9 a 10 instead of an 8 or visa versa so rfLens could be 1 FC off
- int tol1 = (fcLens[best1]>fcLens[best2]) ? fcLens[best1] : fcLens[best2];
+ }
+ // 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
+ // 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 (ii<0) ii=7; // oops we went too far
+ if (ii<0) return 0; // oops we went too far
- // TODO: take top 3 answers and compare to known Field clocks to get top 2
+ return clk[ii];
+}
- uint32_t fcs=0;
- // PrintAndLog("DEBUG: Best %d best2 %d best3 %d, clk %d, clk2 %d",fcLens[best1],fcLens[best2],fcLens[best3],clk[i],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]){
- fcs = (((uint32_t)clk[ii])<<16) | (((uint32_t)fcLens[best1])<<8) | ((fcLens[best2]));
- } else {
- fcs = (((uint32_t)clk[ii])<<16) | (((uint32_t)fcLens[best2])<<8) | ((fcLens[best1]));
+ 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;
}
projects / proxmark3-svn / blobdiff