CHG: `lf em` - added @marshmellow42 's changes

[proxmark3-svn] / common / crc.c

diff --git a/common/crc.c b/common/crc.c
index 2f11f5f45f6c97386ffb6a595b014b05bd7a3e3b..f9a15234ed951da5f95e739e2ebf7c2c150b4eb1 100644 (file)
--- a/common/crc.c
+++ b/common/crc.c
@@ -29,23 +29,22 @@ void crc_init(crc_t *crc, int order, uint32_t polynom, uint32_t initial_value, u
 }
 
 void crc_clear(crc_t *crc) {
+       
        crc->state = crc->initial_value & crc->mask;
        if (crc->refin) 
                crc->state = reflect(crc->state, crc->order);
 }
 
-void crc_update(crc_t *crc, uint32_t indata, int data_width){
-
-       //reflected
-       if (crc->refin) indata = reflect(indata, data_width);
+void crc_update2(crc_t *crc, uint32_t data, int data_width){
+       
+       if (crc->refin) 
+               data = reflect(data, data_width);
        
        // Bring the next byte into the remainder.
-       crc->state ^= indata << (crc->order - data_width);
+       crc->state ^= data << (crc->order - data_width);
        
-       for( uint8_t bit = data_width; bit > 0; --bit) {
-               
-               
-                // Try to divide the current data bit.
+       for( uint8_t bit = data_width; bit > 0; --bit) {                
+
                if (crc->state & crc->topbit)
                        crc->state = (crc->state << 1) ^ crc->polynom;
                else
@@ -53,9 +52,10 @@ void crc_update(crc_t *crc, uint32_t indata, int data_width){
        }
 }
 
-void crc_update2(crc_t *crc, uint32_t data, int data_width)
+void crc_update(crc_t *crc, uint32_t data, int data_width)
 {
-       if (crc->refin) data = reflect(data, data_width);
+       if (crc->refin) 
+               data = reflect(data, data_width);
        
        int i;
        for(i=0; i<data_width; i++) {
@@ -68,7 +68,6 @@ void crc_update2(crc_t *crc, uint32_t data, int data_width)
        }
 }
 
-
 uint32_t crc_finish(crc_t *crc) {
        uint32_t val = crc->state;
        if (crc->refout) val = reflect(val, crc->order);
@@ -96,7 +95,7 @@ uint32_t CRC8Maxim(uint8_t *buff, size_t size) {
        crc_t crc;
        crc_init_ref(&crc, 8, 0x31, 0, 0, TRUE, TRUE);  
        for ( int i=0; i < size; ++i)
-               crc_update(&crc, buff[i], 8);
+               crc_update2(&crc, buff[i], 8);
        return crc_finish(&crc);
 }
 
@@ -115,7 +114,7 @@ uint32_t CRC8Legic(uint8_t *buff, size_t size) {
        crc_t crc;
        crc_init_ref(&crc, 8, 0x63, 0x55, 0, TRUE, TRUE);
        for ( int i = 0; i < size; ++i)
-               crc_update(&crc, buff[i], 8);
+               crc_update2(&crc, buff[i], 8);
        return reflect(crc_finish(&crc), 8);
 }
 
@@ -139,7 +138,7 @@ uint32_t CRC16_DNP(uint8_t *buff, size_t size) {
        crc_t crc;
        crc_init_ref(&crc, 16, 0x3d65, 0, 0xffff, TRUE, TRUE);
        for ( int i=0; i < size; ++i)
-               crc_update(&crc, buff[i], 8);
+               crc_update2(&crc, buff[i], 8);
        
        return BSWAP_16(crc_finish(&crc));
 }