X-Git-Url: http://git.zerfleddert.de/cgi-bin/gitweb.cgi/proxmark3-svn/blobdiff_plain/c783fd1bb83f9f655893b1f349bbdf26ede00a6f..e39a92bb1d876f880ad8cbea82921838422358e8:/common/lfdemod.c

diff --git a/common/lfdemod.c b/common/lfdemod.c
index 8324c440..2ee66a52 100644
--- a/common/lfdemod.c
+++ b/common/lfdemod.c
@@ -62,7 +62,7 @@ uint8_t parityTest(uint32_t bits, uint8_t bitLen, uint8_t pType)
 	for (uint8_t i = 0; i < bitLen; i++){
 		ans ^= ((bits >> i) & 1);
 	}
-	//PrintAndLog("DEBUG: ans: %d, ptype: %d",ans,pType);
+	if (g_debugMode) prnt("DEBUG: ans: %d, ptype: %d, bits: %08X",ans,pType,bits);
 	return (ans == pType);
 }
 
@@ -73,11 +73,13 @@ size_t removeParity(uint8_t *BitStream, size_t startIdx, uint8_t pLen, uint8_t p
 {
 	uint32_t parityWd = 0;
 	size_t j = 0, bitCnt = 0;
-	for (int word = 0; word < (bLen); word+=pLen){
-		for (int bit=0; bit < pLen; bit++){
+	for (int word = 0; word < (bLen); word+=pLen) {
+		for (int bit=0; bit < pLen; bit++) {
 			parityWd = (parityWd << 1) | BitStream[startIdx+word+bit];
 			BitStream[j++] = (BitStream[startIdx+word+bit]);
 		}
+		if (word+pLen >= bLen) break;
+
 		j--; // overwrite parity with next data
 		// if parity fails then return 0
 		switch (pType) {
@@ -148,6 +150,9 @@ 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)
 {
+	// 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){
@@ -1372,10 +1377,10 @@ uint16_t countFC(uint8_t *BitStream, size_t size, uint8_t fskAdj)
 	uint8_t fcLens[] = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};
 	uint16_t fcCnts[] = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};
 	uint8_t fcLensFnd = 0;
-	uint8_t lastFCcnt=0;
+	uint8_t lastFCcnt = 0;
 	uint8_t fcCounter = 0;
 	size_t i;
-	if (size == 0) return 0;
+	if (size < 180) return 0;
 
 	// prime i to first up transition
 	for (i = 160; i < size-20; i++)