mirror of
https://github.com/RfidResearchGroup/proxmark3.git
synced 2024-11-14 13:44:49 +08:00
bd20f8f478
I have kept whatever copyright notices exist. Please add your own copyright notice if you have made any nontrivial changes or additions to the code. There are several files without any attribution, currently.
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 */
|