//-----------------------------------------------------------------------------
//
// 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 Paradox tag commands
// FSK2a, rf/50, 96 bits (completely known)
//-----------------------------------------------------------------------------
#include <stdio.h>
#include <string.h>
#include <inttypes.h>
#include "cmdlfparadox.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);
static int usage_lf_paradox_sim(void) {
PrintAndLogEx(NORMAL, "Enables simulation of Paradox card with specified card number.");
PrintAndLogEx(NORMAL, "Simulation runs until the button is pressed or another USB command is issued.");
PrintAndLogEx(NORMAL, "The facility-code is 8-bit and the card number is 16-bit. Larger values are truncated.");
PrintAndLogEx(NORMAL, "");
PrintAndLogEx(NORMAL, "Usage: lf paradox sim [h] <Facility-Code> <Card-Number>");
PrintAndLogEx(NORMAL, "Options:");
PrintAndLogEx(NORMAL, " h : this help");
PrintAndLogEx(NORMAL, " <Facility-Code> : 8-bit value facility code");
PrintAndLogEx(NORMAL, " <Card Number> : 16-bit value card number");
PrintAndLogEx(NORMAL, "");
PrintAndLogEx(NORMAL, "Examples:");
PrintAndLogEx(NORMAL, " lf paradox sim 123 11223");
return PM3_SUCCESS;
}
//by marshmellow
//Paradox Prox demod - FSK2a RF/50 with preamble of 00001111 (then manchester encoded)
//print full Paradox Prox ID and some bit format details if found
static int CmdParadoxDemod(const char *Cmd) {
(void)Cmd; // Cmd is not used so far
//raw fsk demod no manchester decoding no start bit finding just get binary from wave
uint8_t bits[MAX_GRAPH_TRACE_LEN] = {0};
size_t size = getFromGraphBuf(bits);
if (size == 0) {
PrintAndLogEx(DEBUG, "DEBUG: Error - Paradox not enough samples");
return PM3_ESOFT;
}
uint32_t hi2 = 0, hi = 0, lo = 0;
int waveIdx = 0;
//get binary from fsk wave
int idx = detectParadox(bits, &size, &hi2, &hi, &lo, &waveIdx);
if (idx < 0) {
if (idx == -1)
PrintAndLogEx(DEBUG, "DEBUG: Error - Paradox not enough samples");
else if (idx == -2)
PrintAndLogEx(DEBUG, "DEBUG: Error - Paradox just noise detected");
else if (idx == -3)
PrintAndLogEx(DEBUG, "DEBUG: Error - Paradox problem during FSK demod");
else if (idx == -4)
PrintAndLogEx(DEBUG, "DEBUG: Error - Paradox preamble not found");
else if (idx == -5)
PrintAndLogEx(DEBUG, "DEBUG: Error - Paradox error in Manchester data, size %d", size);
else
PrintAndLogEx(DEBUG, "DEBUG: Error - Paradox error demoding fsk %d", idx);
return PM3_ESOFT;
}
setDemodBuff(bits, size, idx);
setClockGrid(50, waveIdx + (idx * 50));
if (hi2 == 0 && hi == 0 && lo == 0) {
PrintAndLogEx(DEBUG, "DEBUG: Error - Paradox no value found");
return PM3_ESOFT;
}
uint32_t fc = ((hi & 0x3) << 6) | (lo >> 26);
uint32_t cardnum = (lo >> 10) & 0xFFFF;
uint32_t rawLo = bytebits_to_byte(bits + idx + 64, 32);
uint32_t rawHi = bytebits_to_byte(bits + idx + 32, 32);
uint32_t rawHi2 = bytebits_to_byte(bits + idx, 32);
PrintAndLogEx(NORMAL, "Paradox TAG ID: %x%08x - FC: %d - Card: %d - Checksum: %02x - RAW: %08x%08x%08x",
hi >> 10,
(hi & 0x3) << 26 | (lo >> 10),
fc, cardnum,
(lo >> 2) & 0xFF,
rawHi2,
rawHi,
rawLo
);
PrintAndLogEx(DEBUG, "DEBUG: Paradox idx: %d, len: %d, Printing Demod Buffer:", idx, size);
if (g_debugMode)
printDemodBuff();
return PM3_SUCCESS;
}
//by marshmellow
//see ASKDemod for what args are accepted
static int CmdParadoxRead(const char *Cmd) {
lf_read(true, 10000);
return CmdParadoxDemod(Cmd);
}
static int CmdParadoxSim(const char *Cmd) {
char cmdp = tolower(param_getchar(Cmd, 0));
if (strlen(Cmd) == 0 || cmdp == 'h') return usage_lf_paradox_sim();
uint32_t facilitycode = 0, cardnumber = 0, fc = 0, cn = 0;
uint8_t bs[96];
memset(bs, 0x00, sizeof(bs));
// Paradox uses: fcHigh: 10, fcLow: 8, clk: 50, invert: 1 FSK2a
uint8_t clk = 50, invert = 1, high = 10, low = 8;
if (sscanf(Cmd, "%u %u", &fc, &cn) != 2) return usage_lf_paradox_sim();
facilitycode = (fc & 0x000000FF);
cardnumber = (cn & 0x0000FFFF);
// if ( GetParadoxBits(facilitycode, cardnumber, bs) != PM3_SUCCESS) {
// PrintAndLogEx(ERR, "Error with tag bitstream generation.");
// return 1;
// }
PrintAndLogEx(NORMAL, "Simulating Paradox - Facility Code: %u, CardNumber: %u", facilitycode, cardnumber);
lf_fsksim_t *payload = calloc(1, sizeof(lf_fsksim_t) + sizeof(bs));
payload->fchigh = high;
payload->fclow = low;
payload->separator = invert;
payload->clock = clk;
memcpy(payload->data, bs, sizeof(bs));
clearCommandBuffer();
SendCommandNG(CMD_LF_FSK_SIMULATE, (uint8_t *)payload, sizeof(lf_fsksim_t) + sizeof(bs));
free(payload);
PacketResponseNG resp;
WaitForResponse(CMD_LF_FSK_SIMULATE, &resp);
PrintAndLogEx(INFO, "Done");
if (resp.status != PM3_EOPABORTED)
return resp.status;
return PM3_SUCCESS;
}
static command_t CommandTable[] = {
{"help", CmdHelp, AlwaysAvailable, "This help"},
{"demod", CmdParadoxDemod, AlwaysAvailable, "Demodulate a Paradox FSK tag from the GraphBuffer"},
{"read", CmdParadoxRead, IfPm3Lf, "Attempt to read and Extract tag data from the antenna"},
// {"clone", CmdParadoxClone, IfPm3Lf, "clone paradox tag"},
{"sim", CmdParadoxSim, IfPm3Lf, "simulate paradox tag"},
{NULL, NULL, NULL, NULL}
};
static int CmdHelp(const char *Cmd) {
(void)Cmd; // Cmd is not used so far
CmdsHelp(CommandTable);
return PM3_SUCCESS;
}
int CmdLFParadox(const char *Cmd) {
clearCommandBuffer();
return CmdsParse(CommandTable, Cmd);
}
// loop to get raw paradox waveform then FSK demodulate the TAG ID from it
int detectParadox(uint8_t *dest, size_t *size, uint32_t *hi2, uint32_t *hi, uint32_t *lo, int *waveStartIdx) {
//make sure buffer has data
if (*size < 96 * 50) return -1;
if (getSignalProperties()->isnoise) return -2;
// FSK demodulator
*size = fskdemod(dest, *size, 50, 1, 10, 8, waveStartIdx); // paradox fsk2a
//did we get a good demod?
if (*size < 96) return -3;
// 00001111 bit pattern represent start of frame, 01 pattern represents a 0 and 10 represents a 1
size_t startIdx = 0;
uint8_t preamble[] = {0, 0, 0, 0, 1, 1, 1, 1};
if (!preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx))
return -4; //preamble not found
size_t numStart = startIdx + sizeof(preamble);
// final loop, go over previously decoded FSK data and manchester decode into usable tag ID
for (size_t idx = numStart; (idx - numStart) < *size - sizeof(preamble); idx += 2) {
if (dest[idx] == dest[idx + 1])
return -5; //not manchester data
*hi2 = (*hi2 << 1) | (*hi >> 31);
*hi = (*hi << 1) | (*lo >> 31);
//Then, shift in a 0 or one into low
*lo <<= 1;
if (dest[idx] && !dest[idx + 1]) // 1 0
*lo |= 1;
else // 0 1
*lo |= 0;
}
return (int)startIdx;
}
int demodParadox(void) {
return CmdParadoxDemod("");
}