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CHG: merged the forum user @jason 's fixes to LEGIC. *UNTESTED*

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CHG: changed the CRC implementations.
This commit is contained in:
iceman1001 2016-07-28 21:41:44 +02:00
commit 3e134b4c20
16 changed files with 1368 additions and 163 deletions
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136
common/crc.c
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@ -5,66 +5,136 @@
//-----------------------------------------------------------------------------
// Generic CRC calculation code.
//-----------------------------------------------------------------------------
// the Check value below in the comments is CRC of the string '123456789'
//
#include "crc.h"
#include "util.h"
#include <stdint.h>
#include <stddef.h>
void crc_init(crc_t *crc, int order, uint32_t polynom, uint32_t initial_value, uint32_t final_xor)
{
void crc_init_ref(crc_t *crc, int order, uint32_t polynom, uint32_t initial_value, uint32_t final_xor, bool refin, bool refout) {
crc_init(crc, order, polynom, initial_value, final_xor);
crc->refin = refin;
crc->refout = refout;
crc_clear(crc);
}
void crc_init(crc_t *crc, int order, uint32_t polynom, uint32_t initial_value, uint32_t final_xor) {
crc->order = order;
crc->topbit = BITMASK( order-1 );
crc->polynom = polynom;
crc->initial_value = initial_value;
crc->final_xor = final_xor;
crc->mask = (1L<<order)-1;
crc->refin = FALSE;
crc->refout = FALSE;
crc_clear(crc);
}
void crc_update(crc_t *crc, uint32_t data, int data_width)
{
for( int i=0; i < data_width; i++) {
int oldstate = crc->state;
crc->state = crc->state >> 1;
if( (oldstate^data) & 1 ) {
crc->state ^= crc->polynom;
}
data >>= 1;
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);
// Bring the next byte into the remainder.
crc->state ^= indata << (crc->order - data_width);
for( uint8_t bit = data_width; bit > 0; --bit) {
// Try to divide the current data bit.
if (crc->state & crc->topbit)
crc->state = (crc->state << 1) ^ crc->polynom;
else
crc->state = (crc->state << 1);
}
}
void crc_clear(crc_t *crc)
{
crc->state = crc->initial_value & crc->mask;
uint32_t crc_finish(crc_t *crc) {
uint32_t val = crc->state;
if (crc->refout) val = reflect(val, crc->order);
return ( val ^ crc->final_xor ) & crc->mask;
}
uint32_t crc_finish(crc_t *crc)
{
return ( crc->state ^ crc->final_xor ) & crc->mask;
/*
static void print_crc(crc_t *crc) {
printf(" Order %d\n Poly %x\n Init %x\n Final %x\n Mask %x\n topbit %x\n RefIn %s\n RefOut %s\n State %x\n",
crc->order,
crc->polynom,
crc->initial_value,
crc->final_xor,
crc->mask,
crc->topbit,
(crc->refin) ? "TRUE":"FALSE",
(crc->refout) ? "TRUE":"FALSE",
crc->state
);
}
*/
//credits to iceman
// width=8 poly=0x31 init=0x00 refin=true refout=true xorout=0x00 check=0xA1 name="CRC-8/MAXIM"
uint32_t CRC8Maxim(uint8_t *buff, size_t size) {
crc_t crc;
crc_init(&crc, 9, 0x8c, 0x00, 0x00);
crc_clear(&crc);
for (size_t i=0; i < size; ++i)
crc_init_ref(&crc, 8, 0x31, 0, 0, TRUE, TRUE);
for ( int i=0; i < size; ++i)
crc_update(&crc, buff[i], 8);
return crc_finish(&crc);
}
//credits to iceman
uint32_t CRC8Legic(uint8_t *buff, size_t size) {
// Poly 0x63, reversed poly 0xC6, Init 0x55, Final 0x00
// width=4 poly=0xC, reversed poly=0x7 init=0x5 refin=true refout=true xorout=0x0000 check= name="CRC-4/LEGIC"
// width=8 poly=0x63, reversed poly=0x8D init=0x55 refin=true refout=true xorout=0x0000 check=0xC6 name="CRC-8/LEGIC"
// the CRC needs to be reversed before returned.
uint32_t CRC8Legic(uint8_t *buff, size_t size) {
crc_t crc;
crc_init(&crc, 8, 0xC6, 0x55, 0);
crc_clear(&crc);
crc_init_ref(&crc, 8, 0x63, 0x55, 0, TRUE, TRUE);
for ( int i = 0; i < size; ++i)
crc_update(&crc, buff[i], 8);
return SwapBits(crc_finish(&crc), 8);
return reflect(crc_finish(&crc), 8);
}
// credits to marshmellow
// width=8 poly=0xA3, reversed poly=0x8B, init=0xB0 refin=true refout=true xorout=0x00 check=0x28 name="CRC-8/JA"
uint32_t CRC8ja(uint8_t *buff, size_t size) {
crc_t crc;
crc_init_ref(&crc, 8, 0xA3, 0x42, 0x00, TRUE, TRUE);
for ( int i=0; i < size; ++i)
crc_update(&crc, buff[i], 8);
return crc_finish(&crc);
//return reflect(crc_finish(&crc), 8);
}
// This CRC-16 is used in Legic Advant systems.
// width=8 poly=0xB400, reversed poly=0x init=depends refin=true refout=true xorout=0x0000 check= name="CRC-16/LEGIC"
uint32_t CRC16Legic(uint8_t *buff, size_t size, uint8_t uidcrc) {
#define CRC16_POLY_LEGIC 0xB400
//uint8_t initial = reflect(uidcrc, 8);
uint16_t initial = uidcrc;
initial |= initial << 8;
crc_t crc;
crc_init_ref(&crc, 16, CRC16_POLY_LEGIC, initial, 0, TRUE, TRUE);
for ( int i=0; i < size; ++i)
crc_update(&crc, buff[i], 8);
return reflect(crc_finish(&crc), 16);
}
//w=16 poly=0x3d65 init=0x0000 refin=true refout=true xorout=0xffff check=0xea82 name="CRC-16/DNP"
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);
return BSWAP_16(crc_finish(&crc));
}
//width=16 poly=0x1021 init=0x1d0f refin=false refout=false xorout=0x0000 check=0xe5cc name="CRC-16/AUG-CCITT"
uint32_t CRC16_CCITT(uint8_t *buff, size_t size) {
crc_t crc;
crc_init(&crc, 16, 0x1021, 0x1d0f, 0);
for ( int i=0; i < size; ++i)
crc_update(&crc, buff[i], 8);
return crc_finish(&crc);
}