//**********************************************************************************************
//---------------------------------Utilities Section--------------------------------------------
//**********************************************************************************************
-
+#define LOWEST_DEFAULT_CLOCK 32
//to allow debug print calls when used not on device
void dummy(char *fmt, ...){}
#ifndef ON_DEVICE
return i;
}
+int getClosestClock(int testclk) {
+ uint8_t fndClk[] = {8,16,32,40,50,64,128};
+
+ for (uint8_t clkCnt = 0; clkCnt<7; clkCnt++)
+ if (testclk >= fndClk[clkCnt]-(fndClk[clkCnt]/8) && testclk <= fndClk[clkCnt]+1)
+ return fndClk[clkCnt];
+
+ return 0;
+}
+
+void getNextLow(uint8_t samples[], size_t size, int low, size_t *i) {
+ while ((samples[*i] > low) && (*i < size))
+ *i+=1;
+}
+
+void getNextHigh(uint8_t samples[], size_t size, int high, size_t *i) {
+ while ((samples[*i] < high) && (*i < size))
+ *i+=1;
+}
+
+// load wave counters
+bool loadWaveCounters(uint8_t samples[], size_t size, int lowToLowWaveLen[], int highToLowWaveLen[], int *waveCnt, int *skip, int *minClk, int *high, int *low) {
+ size_t i=0, firstLow, firstHigh;
+ size_t testsize = (size < 512) ? size : 512;
+
+ if ( getHiLo(samples, testsize, high, low, 80, 80) == -1 ) {
+ if (g_debugMode==2) prnt("DEBUG STT: just noise detected - quitting");
+ return false; //just noise
+ }
+
+ // get to first full low to prime loop and skip incomplete first pulse
+ getNextHigh(samples, size, *high, &i);
+ getNextLow(samples, size, *low, &i);
+ *skip = i;
+
+ // populate tmpbuff buffer with pulse lengths
+ while (i < size) {
+ // measure from low to low
+ firstLow = i;
+ //find first high point for this wave
+ getNextHigh(samples, size, *high, &i);
+ firstHigh = i;
+
+ getNextLow(samples, size, *low, &i);
+
+ if (*waveCnt >= (size/LOWEST_DEFAULT_CLOCK))
+ break;
+
+ highToLowWaveLen[*waveCnt] = i - firstHigh; //first high to first low
+ lowToLowWaveLen[*waveCnt] = i - firstLow;
+ *waveCnt += 1;
+ if (i-firstLow < *minClk && i < size) {
+ *minClk = i - firstLow;
+ }
+ }
+ return true;
+}
+
//by marshmellow
//amplify based on ask edge detection - not accurate enough to use all the time
void askAmp(uint8_t *BitStream, size_t size) {
// by marshmellow
// to help detect clocks on heavily clipped samples
// based on count of low to low
-int DetectStrongAskClock(uint8_t dest[], size_t size, uint8_t high, uint8_t low, int *clock) {
- uint8_t fndClk[] = {8,16,32,40,50,64,128};
+int DetectStrongAskClock(uint8_t dest[], size_t size, int high, int low, int *clock) {
size_t startwave;
size_t i = 100;
size_t minClk = 255;
int shortestWaveIdx = 0;
// get to first full low to prime loop and skip incomplete first pulse
- while ((dest[i] < high) && (i < size))
- ++i;
- while ((dest[i] > low) && (i < size))
- ++i;
+ getNextHigh(dest, size, high, &i);
+ getNextLow(dest, size, low, &i);
// loop through all samples
while (i < size) {
// measure from low to low
- while ((dest[i] > low) && (i < size))
- ++i;
startwave = i;
- while ((dest[i] < high) && (i < size))
- ++i;
- while ((dest[i] > low) && (i < size))
- ++i;
+
+ getNextHigh(dest, size, high, &i);
+ getNextLow(dest, size, low, &i);
//get minimum measured distance
if (i-startwave < minClk && i < size) {
minClk = i - startwave;
}
}
// set clock
- if (g_debugMode==2) prnt("DEBUG ASK: detectstrongASKclk smallest wave: %d",minClk);
- for (uint8_t clkCnt = 0; clkCnt<7; clkCnt++) {
- if (minClk >= fndClk[clkCnt]-(fndClk[clkCnt]/8) && minClk <= fndClk[clkCnt]+1) {
- *clock = fndClk[clkCnt];
- return shortestWaveIdx;
- }
- }
- return 0;
+ if (g_debugMode==2) prnt("DEBUG ASK: DetectStrongAskClock smallest wave: %d",minClk);
+ *clock = getClosestClock(minClk);
+ if (*clock == 0)
+ return 0;
+
+ return shortestWaveIdx;
}
// by marshmellow
//**********************************************************************************************
// look for Sequence Terminator - should be pulses of clk*(1 or 2), clk*2, clk*(1.5 or 2), by idx we mean graph position index...
-bool findST(int *stStopLoc, int *stStartIdx, int lowToLowWaveLen[], int highToLowWaveLen[], int clk, int tol, int buffSize, int *i) {
+bool findST(int *stStopLoc, int *stStartIdx, int lowToLowWaveLen[], int highToLowWaveLen[], int clk, int tol, int buffSize, size_t *i) {
for (; *i < buffSize - 4; *i+=1) {
*stStartIdx += lowToLowWaveLen[*i]; //caution part of this wave may be data and part may be ST.... to be accounted for in main function for now...
if (lowToLowWaveLen[*i] >= clk*1-tol && lowToLowWaveLen[*i] <= (clk*2)+tol && highToLowWaveLen[*i] < clk+tol) { //1 to 2 clocks depending on 2 bits prior
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};
int clk = 0;
int tol = 0;
- int i, j, skip, start, end, low, high, minClk, waveStart;
+ int j, high, low, skip, start, end, minClk=255;
+ size_t i = 0;
//probably should malloc... || test if memory is available ... handle device side? memory danger!!! [marshmellow]
- int tmpbuff[bufsize / 32]; // low to low wave count //guess rf/32 clock, if click is smaller we will only have room for a fraction of the samples captured
- int waveLen[bufsize / 32]; // high to low wave count //if clock is larger then we waste memory in array size that is not needed...
- size_t testsize = (bufsize < 512) ? bufsize : 512;
+ int tmpbuff[bufsize / LOWEST_DEFAULT_CLOCK]; // low to low wave count //guess rf/32 clock, if click is smaller we will only have room for a fraction of the samples captured
+ int waveLen[bufsize / LOWEST_DEFAULT_CLOCK]; // high to low wave count //if clock is larger then we waste memory in array size that is not needed...
+ //size_t testsize = (bufsize < 512) ? bufsize : 512;
int phaseoff = 0;
high = low = 128;
memset(tmpbuff, 0, sizeof(tmpbuff));
memset(waveLen, 0, sizeof(waveLen));
- if ( getHiLo(buffer, testsize, &high, &low, 80, 80) == -1 ) {
- if (g_debugMode==2) prnt("DEBUG STT: just noise detected - quitting");
- return false; //just noise
- }
- i = 0;
- j = 0;
- minClk = 255;
- // get to first full low to prime loop and skip incomplete first pulse
- while ((buffer[i] < high) && (i < bufsize))
- ++i;
- while ((buffer[i] > low) && (i < bufsize))
- ++i;
- skip = i;
-
- // populate tmpbuff buffer with pulse lengths
- while (i < bufsize) {
- // measure from low to low
- while ((buffer[i] > low) && (i < bufsize))
- ++i;
- start= i;
- while ((buffer[i] < high) && (i < bufsize))
- ++i;
- //first high point for this wave
- waveStart = i;
- while ((buffer[i] > low) && (i < bufsize))
- ++i;
- if (j >= (bufsize/32)) {
- break;
- }
- waveLen[j] = i - waveStart; //first high to first low
- tmpbuff[j++] = i - start;
- if (i-start < minClk && i < bufsize) {
- minClk = i - start;
- }
- }
+ if (!loadWaveCounters(buffer, bufsize, tmpbuff, waveLen, &j, &skip, &minClk, &high, &low)) return false;
// set clock - might be able to get this externally and remove this work...
- if (!clk) {
- for (uint8_t clkCnt = 0; clkCnt<7; clkCnt++) {
- tol = fndClk[clkCnt]/8;
- if (minClk >= fndClk[clkCnt]-tol && minClk <= fndClk[clkCnt]+1) {
- clk=fndClk[clkCnt];
- break;
- }
- }
- // clock not found - ERROR
- if (!clk) {
- if (g_debugMode==2) prnt("DEBUG STT: clock not found - quitting");
- return false;
- }
- } else tol = clk/8;
-
+ clk = getClosestClock(minClk);
+ // clock not found - ERROR
+ if (clk == 0) {
+ if (g_debugMode==2) prnt("DEBUG STT: clock not found - quitting");
+ return false;
+ }
*foundclock = clk;
- i=0;
+
+ tol = clk/8;
if (!findST(&start, &skip, tmpbuff, waveLen, clk, tol, j, &i)) {
// first ST not found - ERROR
if (g_debugMode==2) prnt("DEBUG STT: first STT not found - quitting");
}
//by marshmellow
-//take 11 10 01 11 00 and make 01100 ... miller decoding
+//take 11 10 01 11 00 and make 01100 ... miller decoding
//check for phase errors - should never have half a 1 or 0 by itself and should never exceed 1111 or 0000 in a row
//decodes miller encoded binary
//NOTE askrawdemod will NOT demod miller encoded ask unless the clock is manually set to 1/2 what it is detected as!
-/*int millerRawDecode(uint8_t *BitStream, size_t *size, int invert) {
+int millerRawDecode(uint8_t *BitStream, size_t *size, int invert) {
if (*size < 16) return -1;
- uint16_t MaxBits = 512, errCnt = 0, bestErr = 1000, bestRun = 0;
- size_t i, ii, bitCnt=0;
- uint8_t alignCnt = 0, curBit = BitStream[0];
+ uint16_t MaxBits = 512, errCnt = 0;
+ size_t i, bitCnt=0;
+ uint8_t alignCnt = 0, curBit = BitStream[0], alignedIdx = 0;
+ uint8_t halfClkErr = 0;
//find alignment, needs 4 1s or 0s to properly align
- for (i=1; i < *size; i++) {
+ for (i=1; i < *size-1; i++) {
alignCnt = (BitStream[i] == curBit) ? alignCnt+1 : 0;
curBit = BitStream[i];
if (alignCnt == 4) break;
if (g_debugMode) prnt("ERROR MillerDecode: alignment not found so either your bitstream is not miller or your data does not have a 101 in it");
return -1;
}
+ alignedIdx = (i-1) % 2;
+ for (i=alignedIdx; i < *size-3; i+=2) {
+ halfClkErr = (uint8_t)((halfClkErr << 1 | BitStream[i]) & 0xFF);
+ if ( (halfClkErr & 0x7) == 5 || (halfClkErr & 0x7) == 2 || (i > 2 && (halfClkErr & 0x7) == 0) || (halfClkErr & 0x1F) == 0x1F) {
+ errCnt++;
+ BitStream[bitCnt++] = 7;
+ continue;
+ }
+ BitStream[bitCnt++] = BitStream[i] ^ BitStream[i+1] ^ invert;
-}*/
+ if (bitCnt > MaxBits) break;
+ }
+ *size = bitCnt;
+ return errCnt;
+}
//by marshmellow
//take 01 or 10 = 1 and 11 or 00 = 0
return (int) startIdx;
}
-
// by iceman
// find Visa2000 preamble in already demoded data
int Visa2kDemod_AM(uint8_t *dest, size_t *size) {
projects / proxmark3-svn / blobdiff