mirror of
https://github.com/RfidResearchGroup/proxmark3.git
synced 2024-12-30 20:23:46 +08:00
48 lines
1.7 KiB
C
48 lines
1.7 KiB
C
//-----------------------------------------------------------------------------
|
|
// This code is licensed to you under the terms of the GNU GPL, version 2 or,
|
|
// at your option, any later version. See the LICENSE.txt file for the text of
|
|
// the license.
|
|
//-----------------------------------------------------------------------------
|
|
// Generic CRC calculation code.
|
|
//-----------------------------------------------------------------------------
|
|
|
|
#ifndef __CRC_H
|
|
#define __CRC_H
|
|
|
|
#include <stdint.h>
|
|
|
|
typedef struct crc {
|
|
uint32_t state;
|
|
int order;
|
|
uint32_t polynom;
|
|
uint32_t initial_value;
|
|
uint32_t final_xor;
|
|
uint32_t mask;
|
|
} crc_t;
|
|
|
|
/* Initialize a crc structure. order is the order of the polynom, e.g. 32 for a CRC-32
|
|
* polynom is the CRC polynom. initial_value is the initial value of a clean state.
|
|
* final_xor is XORed onto the state before returning it from crc_result(). */
|
|
extern void crc_init(crc_t *crc, int order, uint32_t polynom, uint32_t initial_value, uint32_t final_xor);
|
|
|
|
/* Update the crc state. data is the data of length data_width bits (only the the
|
|
* data_width lower-most bits are used).
|
|
*/
|
|
extern void crc_update(crc_t *crc, uint32_t data, int data_width);
|
|
|
|
/* Clean the crc state, e.g. reset it to initial_value */
|
|
extern void crc_clear(crc_t *crc);
|
|
|
|
/* Get the result of the crc calculation */
|
|
extern uint32_t crc_finish(crc_t *crc);
|
|
|
|
/* Static initialization of a crc structure */
|
|
#define CRC_INITIALIZER(_order, _polynom, _initial_value, _final_xor) { \
|
|
.state = ((_initial_value) & ((1L<<(_order))-1)), \
|
|
.order = (_order), \
|
|
.polynom = (_polynom), \
|
|
.initial_value = (_initial_value), \
|
|
.final_xor = (_final_xor), \
|
|
.mask = ((1L<<(_order))-1) }
|
|
|
|
#endif /* __CRC_H */
|