proxmark3/client/cmdlfnexwatch.c
marshmellow42 b9957414a5 lf read adjustments
add parameter for # bits to read
auto get samples after lf read/snoop (don't need to do a `data samples`
anymore)
add safe function to get DemodBuffer
add some lf demod comments and apply new lf_read function instead of
read then get samples.
fixed output bug in lf t55xx config print
fixed small bug in lf t55xx detect during ST check
2017-04-07 17:28:12 -04:00

90 lines
2.6 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.
//-----------------------------------------------------------------------------
// Low frequency Honeywell NexWatch tag commands
// PSK1 RF/16, RF/2, 128 bits long (known)
//-----------------------------------------------------------------------------
#include <stdio.h>
#include <string.h>
#include <inttypes.h>
#include <stdbool.h>
#include "cmdlfnexwatch.h"
#include "proxmark3.h"
#include "ui.h"
#include "util.h"
#include "graph.h"
#include "cmdparser.h"
#include "cmddata.h"
#include "cmdlf.h"
#include "lfdemod.h"
static int CmdHelp(const char *Cmd);
int CmdPSKNexWatch(const char *Cmd)
{
if (!PSKDemod("", false)) return 0;
uint8_t preamble[28] = {0,0,0,0,0,1,0,1,0,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};
size_t startIdx = 0, size = DemodBufferLen;
bool invert = false;
if (!preambleSearch(DemodBuffer, preamble, sizeof(preamble), &size, &startIdx)){
// if didn't find preamble try again inverting
if (!PSKDemod("1", false)) return 0;
size = DemodBufferLen;
if (!preambleSearch(DemodBuffer, preamble, sizeof(preamble), &size, &startIdx)) return 0;
invert = true;
}
if (size != 128) return 0;
setDemodBuf(DemodBuffer, size, startIdx+4);
startIdx = 8+32; //4 = extra i added, 8 = preamble, 32 = reserved bits (always 0)
//get ID
uint32_t ID = 0;
for (uint8_t wordIdx=0; wordIdx<4; wordIdx++){
for (uint8_t idx=0; idx<8; idx++){
ID = (ID << 1) | DemodBuffer[startIdx+wordIdx+(idx*4)];
}
}
//parity check (TBD)
//checksum check (TBD)
//output
PrintAndLog("NexWatch ID: %d", ID);
if (invert){
PrintAndLog("Had to Invert - probably NexKey");
for (uint8_t idx=0; idx<size; idx++)
DemodBuffer[idx] ^= 1;
}
CmdPrintDemodBuff("x");
return 1;
}
//by marshmellow
//see ASKDemod for what args are accepted
int CmdNexWatchRead(const char *Cmd) {
// read lf silently
lf_read(true, 10000);
// demod and output viking ID
return CmdPSKNexWatch(Cmd);
}
static command_t CommandTable[] = {
{"help", CmdHelp, 1, "This help"},
{"demod", CmdPSKNexWatch, 1, "Demodulate a NexWatch tag (nexkey, quadrakey) from the GraphBuffer"},
{"read", CmdNexWatchRead, 0, "Attempt to Read and Extract tag data from the antenna"},
{NULL, NULL, 0, NULL}
};
int CmdLFNexWatch(const char *Cmd) {
CmdsParse(CommandTable, Cmd);
return 0;
}
int CmdHelp(const char *Cmd) {
CmdsHelp(CommandTable);
return 0;
}