Merge pull request #32 from osysltd/patch-1

[proxmark3-svn] / common / lfdemod.c

diff --git a/common/lfdemod.c b/common/lfdemod.c
index 7e31f53dcccb66b04e3c5d04b809cf5f20308477..e748fddbb15865374b0d337e382710d23136c5c7 100644 (file)
--- a/common/lfdemod.c
+++ b/common/lfdemod.c
@@ -84,7 +84,9 @@ size_t removeParity(uint8_t *BitStream, size_t startIdx, uint8_t pLen, uint8_t p
                        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;
+                               if (parityTest(parityWd, pLen, pType) == 0) 
+                                       return 0; 
+                               break;
                }
                bitCnt+=(pLen-1);
                parityWd = 0;
@@ -148,8 +150,11 @@ 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++;
@@ -582,7 +587,7 @@ 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;
@@ -614,7 +619,7 @@ 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;