X-Git-Url: https://git.zerfleddert.de/cgi-bin/gitweb.cgi/proxmark3-svn/blobdiff_plain/96faed2124908faee3a251b7e5a294327218a7ff..16a9209c042b33d23cf85d07699e8d026e7b288b:/common/lfdemod.c diff --git a/common/lfdemod.c b/common/lfdemod.c index 047c9e28..8bbe5beb 100644 --- a/common/lfdemod.c +++ b/common/lfdemod.c @@ -81,10 +81,9 @@ size_t removeParity(uint8_t *BitStream, size_t startIdx, uint8_t pLen, uint8_t p j--; // overwrite parity with next data // if parity fails then return 0 switch (pType) { - case 3: if (BitStream[j]==1) return 0; break; //should be 0 spacer bit - case 2: if (BitStream[j]==0) return 0; break; //should be 1 spacer bit - default: //test parity - if (parityTest(parityWd, pLen, pType) == 0) return 0; break; + case 3: if (BitStream[j]==1) { return 0; } break; //should be 0 spacer bit + case 2: if (BitStream[j]==0) { return 0; } break; //should be 1 spacer bit + default: if (parityTest(parityWd, pLen, pType) == 0) { return 0; } break; //test parity } bitCnt+=(pLen-1); parityWd = 0; @@ -148,8 +147,11 @@ uint32_t bytebits_to_byteLSBF(uint8_t *src, size_t numbits) //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) { - uint8_t foundCnt=0; - for (int idx=0; idx < *size - pLen; idx++){ + // Sanity check. If preamble length is bigger than bitstream length. + if ( *size <= pLen ) return 0; + + uint8_t foundCnt = 0; + for (int idx = 0; idx < *size - pLen; idx++){ if (memcmp(BitStream+idx, preamble, pLen) == 0){ //first index found foundCnt++; @@ -167,13 +169,13 @@ uint8_t preambleSearch(uint8_t *BitStream, uint8_t *preamble, size_t pLen, size_ //by marshmellow //takes 1s and 0s and searches for EM410x format - output EM ID -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) { //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 0; //allow only 1s and 0s + 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 @@ -184,14 +186,15 @@ uint8_t Em410xDecode(uint8_t *BitStream, size_t *size, size_t *startIdx, uint32_ uint8_t FmtLen = 10; *startIdx = 0; errChk = preambleSearch(BitStream, preamble, sizeof(preamble), size, startIdx); - if (errChk == 0 || *size < 64) return 0; + 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> 63); @@ -259,13 +262,15 @@ int cleanAskRawDemod(uint8_t *BinStream, size_t *size, int clk, int invert, int //by marshmellow void askAmp(uint8_t *BitStream, size_t size) { - for(size_t i = 1; i=30) //large jump up - BitStream[i]=255; - else if(BitStream[i]-BitStream[i-1]<=-20) //large jump down - BitStream[i]=0; + uint8_t last = 128; + for(size_t i = 1; i < size; ++i){ + if (BitStream[i]-BitStream[i-1] >= 30) //large jump up + last = 255; + else if(BitStream[i-1] - BitStream[i] >= 20) //large jump down + last = 0; + + BitStream[i] = last; } - return; } //by marshmellow @@ -580,7 +585,7 @@ int HIDdemodFSK(uint8_t *dest, size_t *size, uint32_t *hi2, uint32_t *hi, uint32 { if (justNoise(dest, *size)) return -1; - size_t numStart=0, size2=*size, startIdx=0; + size_t numStart=0, size2 = *size, startIdx=0; // FSK demodulator *size = fskdemod(dest, size2,50,1,10,8); //fsk2a if (*size < 96*2) return -2; @@ -612,7 +617,7 @@ int ParadoxdemodFSK(uint8_t *dest, size_t *size, uint32_t *hi2, uint32_t *hi, ui { if (justNoise(dest, *size)) return -1; - size_t numStart=0, size2=*size, startIdx=0; + size_t numStart=0, size2 = *size, startIdx=0; // FSK demodulator *size = fskdemod(dest, size2,50,1,10,8); //fsk2a if (*size < 96) return -2; @@ -721,6 +726,39 @@ int FDXBdemodBI(uint8_t *dest, size_t *size) return (int)startIdx; } +// ASK/Diphase fc/64 (inverted Biphase) +// Note: this i s not a demod, this is only a detection +// the parameter *dest needs to be demoded before call +int JablotronDemod(uint8_t *dest, size_t *size){ + //make sure buffer has enough data + if (*size < 64) return -1; + + size_t startIdx = 0; + // 0xFFFF preamble, 64bits + 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 -4; //preamble not found + if (*size != 64) return -3; + + uint8_t checkchksum = 0; + for (int i=16; i < 56; i += 8) { + checkchksum += bytebits_to_byte(dest+startIdx+i,8); + } + checkchksum ^= 0x3A; + + uint8_t crc = bytebits_to_byte(dest+startIdx+56, 8); + + if ( checkchksum != crc ) return -5; + return (int)startIdx; +} + // by marshmellow // FSK Demod then try to locate an AWID ID int AWIDdemodFSK(uint8_t *dest, size_t *size) @@ -764,16 +802,16 @@ int PyramiddemodFSK(uint8_t *dest, size_t *size) return (int)startIdx; } -// find presco preamble 0x10D in already demoded data +// find nedap preamble in already demoded data int NedapDemod(uint8_t *dest, size_t *size) { //make sure buffer has data if (*size < 128) return -3; 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 - //return start position return (int) startIdx; }