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ADD: tnp3.lua can now validate the checkums in the dump

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ADD: added  CRC16 CCITT functionality to LUA
FIX: tnp3.lua is now correctly decryping data while dumping
This commit is contained in:
iceman1001 2014-11-12 23:18:46 +01:00
commit 47cbb2d418
5 changed files with 114 additions and 13 deletions
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23
common/crc16.c
View file

@ -8,6 +8,7 @@
#include "crc16.h"
unsigned short update_crc16( unsigned short crc, unsigned char c )
{
unsigned short i, v, tcrc = 0;
@ -20,3 +21,25 @@ unsigned short update_crc16( unsigned short crc, unsigned char c )
return ((crc >> 8) ^ tcrc)&0xffff;
}
uint16_t crc16(uint8_t const *message, int length, uint16_t remainder, uint16_t polynomial) {
if (length == 0)
return (~remainder);
for (int byte = 0; byte < length; ++byte) {
remainder ^= (message[byte] << 8);
for (uint8_t bit = 8; bit > 0; --bit) {
if (remainder & 0x8000) {
remainder = (remainder << 1) ^ polynomial;
} else {
remainder = (remainder << 1);
}
}
}
return remainder;
}
uint16_t crc16_ccitt(uint8_t const *message, int length) {
return crc16(message, length, 0xffff, 0x1021);
}

5
common/crc16.h
View file

@ -5,10 +5,11 @@
//-----------------------------------------------------------------------------
// CRC16
//-----------------------------------------------------------------------------
#include <stdint.h>
#ifndef __CRC16_H
#define __CRC16_H
unsigned short update_crc16(unsigned short crc, unsigned char c);
uint16_t crc16(uint8_t const *message, int length, uint16_t remainder, uint16_t polynomial);
uint16_t crc16_ccitt(uint8_t const *message, int length);
#endif