github/proxmark3
1
0
Fork 0
mirror of https://github.com/Proxmark/proxmark3.git synced 2025-08-14 02:26:59 -07:00
Code Issues Projects Releases Packages Wiki Activity Actions

FIX: The input handling for "hf 14b write" is now correct. Thanks Asper for spotting the fault.

Browse source 
ADD: crc32.c functionality
This commit is contained in:
iceman1001 2015-01-07 22:56:20 +01:00
commit b5be31f996
3 changed files with 68 additions and 10 deletions
Download patch file Download diff file Expand all files Collapse all files

35
common/crc32.c Normal file
View file

@ -0,0 +1,35 @@
#include <stdint.h>
#include <stddef.h>
#include "crc32.h"
#define htole32(x) (x)
#define CRC32_PRESET 0xFFFFFFFF
static void crc32_byte (uint32_t *crc, const uint8_t value);
static void crc32_byte (uint32_t *crc, const uint8_t value) {
/* x32 + x26 + x23 + x22 + x16 + x12 + x11 + x10 + x8 + x7 + x5 + x4 + x2 + x + 1 */
const uint32_t poly = 0xEDB88320;
*crc ^= value;
for (int current_bit = 7; current_bit >= 0; current_bit--) {
int bit_out = (*crc) & 0x00000001;
*crc >>= 1;
if (bit_out)
*crc ^= poly;
}
}
void crc32 (const uint8_t *data, const size_t len, uint8_t *crc) {
uint32_t desfire_crc = CRC32_PRESET;
for (size_t i = 0; i < len; i++) {
crc32_byte (&desfire_crc, data[i]);
}
*((uint32_t *)(crc)) = htole32 (desfire_crc);
}
void crc32_append (uint8_t *data, const size_t len) {
crc32 (data, len, data + len);
}

15
common/crc32.h Normal file
View file

@ -0,0 +1,15 @@
//-----------------------------------------------------------------------------
// 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.
//-----------------------------------------------------------------------------
// CRC32
//-----------------------------------------------------------------------------
#ifndef __CRC32_H
#define __CRC32_H
void crc32 (const uint8_t *data, const size_t len, uint8_t *crc);
void crc32_append (uint8_t *data, const size_t len);
#endif