[proxmark3-svn] / client / cmdlfem4x.c

//-----------------------------------------------------------------------------
// Copyright (C) 2010 iZsh <izsh at fail0verflow.com>
//
// 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 EM4x commands
//-----------------------------------------------------------------------------

#include <stdio.h>
#include <string.h>
#include <inttypes.h>
#include "proxmark3.h"
#include "ui.h"
#include "graph.h"
#include "cmdmain.h"
#include "cmdparser.h"
#include "cmddata.h"
#include "cmdlf.h"
#include "cmdlfem4x.h"
#include "util.h"
#include "data.h"
#define LF_TRACE_BUFF_SIZE 12000

char *global_em410xId;

static int CmdHelp(const char *Cmd);

/* Read the ID of an EM410x tag.
 * Format:
 *   1111 1111 1           <-- standard non-repeatable header
 *   XXXX [row parity bit] <-- 10 rows of 5 bits for our 40 bit tag ID
 *   ....
 *   CCCC                  <-- each bit here is parity for the 10 bits above in corresponding column
 *   0                     <-- stop bit, end of tag
 */
int CmdEM410xRead(const char *Cmd)
{
  int i, j, clock, header, rows, bit, hithigh, hitlow, first, bit2idx, high, low;
  int parity[4];
  char id[11];
  char id2[11];
  int retested = 0;
  uint8_t BitStream[MAX_GRAPH_TRACE_LEN];
  high = low = 0;

  /* Detect high and lows and clock */
  for (i = 0; i < GraphTraceLen; i++)
  {
    if (GraphBuffer[i] > high)
      high = GraphBuffer[i];
    else if (GraphBuffer[i] < low)
      low = GraphBuffer[i];
  }

  /* get clock */
  clock = GetClock(Cmd, high, 0);

  /* parity for our 4 columns */
  parity[0] = parity[1] = parity[2] = parity[3] = 0;
  header = rows = 0;

  /* manchester demodulate */
  bit = bit2idx = 0;
  for (i = 0; i < (int)(GraphTraceLen / clock); i++)
  {
    hithigh = 0;
    hitlow = 0;
    first = 1;

    /* Find out if we hit both high and low peaks */
    for (j = 0; j < clock; j++)
    {
      if (GraphBuffer[(i * clock) + j] == high)
        hithigh = 1;
      else if (GraphBuffer[(i * clock) + j] == low)
        hitlow = 1;

      /* it doesn't count if it's the first part of our read
       because it's really just trailing from the last sequence */
      if (first && (hithigh || hitlow))
        hithigh = hitlow = 0;
      else
        first = 0;

      if (hithigh && hitlow)
        break;
    }

    /* If we didn't hit both high and low peaks, we had a bit transition */
    if (!hithigh || !hitlow)
      bit ^= 1;

    BitStream[bit2idx++] = bit;
  }

retest:
  /* We go till 5 before the graph ends because we'll get that far below */
  for (i = 1; i < bit2idx - 5; i++)
  {
    /* Step 2: We have our header but need our tag ID */
    if (header == 9 && rows < 10)
    {
      /* Confirm parity is correct */
      if ((BitStream[i] ^ BitStream[i+1] ^ BitStream[i+2] ^ BitStream[i+3]) == BitStream[i+4])
      {
        /* Read another byte! */
        sprintf(id+rows, "%x", (8 * BitStream[i]) + (4 * BitStream[i+1]) + (2 * BitStream[i+2]) + (1 * BitStream[i+3]));
        sprintf(id2+rows, "%x", (8 * BitStream[i+3]) + (4 * BitStream[i+2]) + (2 * BitStream[i+1]) + (1 * BitStream[i]));
        rows++;

        /* Keep parity info */
        parity[0] ^= BitStream[i];
        parity[1] ^= BitStream[i+1];
        parity[2] ^= BitStream[i+2];
        parity[3] ^= BitStream[i+3];

        /* Move 4 bits ahead */
        i += 4;
      }

      /* Damn, something wrong! reset */
      else
      {
        PrintAndLog("Thought we had a valid tag but failed at word %d (i=%d)", rows + 1, i);

        /* Start back rows * 5 + 9 header bits, -1 to not start at same place */
        i -= 9 + (5 * rows) - 5;

        rows = header = 0;
      }
    }

    /* Step 3: Got our 40 bits! confirm column parity */
    else if (rows == 10)
    {
      /* We need to make sure our 4 bits of parity are correct and we have a stop bit */
      if (BitStream[i] == parity[0] && BitStream[i+1] == parity[1] &&
        BitStream[i+2] == parity[2] && BitStream[i+3] == parity[3] &&
        BitStream[i+4] == 0)
      {
        /* Sweet! */
        PrintAndLog("EM410x Tag ID: %s", id);
        PrintAndLog("Unique Tag ID: %s", id2);

		global_em410xId = id;
		
        /* Stop any loops */
        return 1;
      }

      /* Crap! Incorrect parity or no stop bit, start all over */
      else
      {
        rows = header = 0;

        /* Go back 59 bits (9 header bits + 10 rows at 4+1 parity) */
        i -= 59;
      }
    }

    /* Step 1: get our header */
    else if (header < 9)
    {
      /* Need 9 consecutive 1's */
      if (BitStream[i] == 1)
        header++;

      /* We don't have a header, not enough consecutive 1 bits */
      else
        header = 0;
    }
  }

  /* if we've already retested after flipping bits, return */
  if (retested++){
    return 0;
	}

  /* if this didn't work, try flipping bits */
  for (i = 0; i < bit2idx; i++)
    BitStream[i] ^= 1;

  goto retest;
}

/* emulate an EM410X tag
 * Format:
 *   1111 1111 1           <-- standard non-repeatable header
 *   XXXX [row parity bit] <-- 10 rows of 5 bits for our 40 bit tag ID
 *   ....
 *   CCCC                  <-- each bit here is parity for the 10 bits above in corresponding column
 *   0                     <-- stop bit, end of tag
 */
int CmdEM410xSim(const char *Cmd)
{
  int i, n, j, h, binary[4], parity[4];

  /* clock is 64 in EM410x tags */
  int clock = 64;

  /* clear our graph */
  ClearGraph(0);

  /* write it out a few times */
  for (h = 0; h < 4; h++)
  {
    /* write 9 start bits */
    for (i = 0; i < 9; i++)
      AppendGraph(0, clock, 1);

    /* for each hex char */
    parity[0] = parity[1] = parity[2] = parity[3] = 0;
    for (i = 0; i < 10; i++)
    {
      /* read each hex char */
      sscanf(&Cmd[i], "%1x", &n);
      for (j = 3; j >= 0; j--, n/= 2)
        binary[j] = n % 2;

      /* append each bit */
      AppendGraph(0, clock, binary[0]);
      AppendGraph(0, clock, binary[1]);
      AppendGraph(0, clock, binary[2]);
      AppendGraph(0, clock, binary[3]);

      /* append parity bit */
      AppendGraph(0, clock, binary[0] ^ binary[1] ^ binary[2] ^ binary[3]);

      /* keep track of column parity */
      parity[0] ^= binary[0];
      parity[1] ^= binary[1];
      parity[2] ^= binary[2];
      parity[3] ^= binary[3];
    }

    /* parity columns */
    AppendGraph(0, clock, parity[0]);
    AppendGraph(0, clock, parity[1]);
    AppendGraph(0, clock, parity[2]);
    AppendGraph(0, clock, parity[3]);

    /* stop bit */
    AppendGraph(0, clock, 0);
  }

  /* modulate that biatch */
  CmdManchesterMod("");

  /* booyah! */
  RepaintGraphWindow();
  
  CmdLFSim("");
  return 0;
}

/* Function is equivalent of lf read + data samples + em410xread
 * looped until an EM410x tag is detected 
 * 
 * Why is CmdSamples("16000")?
 *  TBD: Auto-grow sample size based on detected sample rate.  IE: If the
 *       rate gets lower, then grow the number of samples
 *  Changed by martin, 4000 x 4 = 16000, 
 *  see http://www.proxmark.org/forum/viewtopic.php?pid=7235#p7235

*/
int CmdEM410xWatch(const char *Cmd)
{
	int read_h = (*Cmd == 'h');
	do
	{
		CmdLFRead(read_h ? "h" : "");
		CmdSamples("16000");	
	} while (
		!CmdEM410xRead("") 
	);
	return 0;
}

int CmdEM410xWatchnSpoof(const char *Cmd)
{
	CmdEM410xWatch(Cmd);
    PrintAndLog("# Replaying : %s",global_em410xId);
    CmdEM410xSim(global_em410xId);
  return 0;
}

/* Read the transmitted data of an EM4x50 tag
 * Format:
 *
 *  XXXXXXXX [row parity bit (even)] <- 8 bits plus parity
 *  XXXXXXXX [row parity bit (even)] <- 8 bits plus parity
 *  XXXXXXXX [row parity bit (even)] <- 8 bits plus parity
 *  XXXXXXXX [row parity bit (even)] <- 8 bits plus parity
 *  CCCCCCCC                         <- column parity bits
 *  0                                <- stop bit
 *  LW                               <- Listen Window
 *
 * This pattern repeats for every block of data being transmitted.
 * Transmission starts with two Listen Windows (LW - a modulated
 * pattern of 320 cycles each (32/32/128/64/64)).
 *
 * Note that this data may or may not be the UID. It is whatever data
 * is stored in the blocks defined in the control word First and Last
 * Word Read values. UID is stored in block 32.
 */
int CmdEM4x50Read(const char *Cmd)
{
  int i, j, startblock, skip, block, start, end, low, high;
  bool complete= false;
  int tmpbuff[MAX_GRAPH_TRACE_LEN / 64];
  char tmp[6];

  high= low= 0;
  memset(tmpbuff, 0, MAX_GRAPH_TRACE_LEN / 64);

  /* first get high and low values */
  for (i = 0; i < GraphTraceLen; i++)
  {
    if (GraphBuffer[i] > high)
      high = GraphBuffer[i];
    else if (GraphBuffer[i] < low)
      low = GraphBuffer[i];
  }

  /* populate a buffer with pulse lengths */
  i= 0;
  j= 0;
  while (i < GraphTraceLen)
  {
    // measure from low to low
    while ((GraphBuffer[i] > low) && (i<GraphTraceLen))
      ++i;
    start= i;
    while ((GraphBuffer[i] < high) && (i<GraphTraceLen))
      ++i;
    while ((GraphBuffer[i] > low) && (i<GraphTraceLen))
      ++i;
    if (j>(MAX_GRAPH_TRACE_LEN/64)) {
      break;
    }
    tmpbuff[j++]= i - start;
  }

  /* look for data start - should be 2 pairs of LW (pulses of 192,128) */
  start= -1;
  skip= 0;
  for (i= 0; i < j - 4 ; ++i)
  {
    skip += tmpbuff[i];
    if (tmpbuff[i] >= 190 && tmpbuff[i] <= 194)
      if (tmpbuff[i+1] >= 126 && tmpbuff[i+1] <= 130)
        if (tmpbuff[i+2] >= 190 && tmpbuff[i+2] <= 194)
          if (tmpbuff[i+3] >= 126 && tmpbuff[i+3] <= 130)
          {
            start= i + 3;
            break;
          }
  }
  startblock= i + 3;

  /* skip over the remainder of the LW */
  skip += tmpbuff[i+1]+tmpbuff[i+2];
  while (skip < MAX_GRAPH_TRACE_LEN && GraphBuffer[skip] > low)
    ++skip;
  skip += 8;

  /* now do it again to find the end */
  end= start;
  for (i += 3; i < j - 4 ; ++i)
  {
    end += tmpbuff[i];
    if (tmpbuff[i] >= 190 && tmpbuff[i] <= 194)
      if (tmpbuff[i+1] >= 126 && tmpbuff[i+1] <= 130)
        if (tmpbuff[i+2] >= 190 && tmpbuff[i+2] <= 194)
          if (tmpbuff[i+3] >= 126 && tmpbuff[i+3] <= 130)
          {
            complete= true;
            break;
          }
  }

  if (start >= 0)
    PrintAndLog("Found data at sample: %i",skip);
  else
  {
    PrintAndLog("No data found!");
    PrintAndLog("Try again with more samples.");
    return 0;
  }

  if (!complete)
  {
    PrintAndLog("*** Warning!");
    PrintAndLog("Partial data - no end found!");
    PrintAndLog("Try again with more samples.");
  }

  /* get rid of leading crap */
  sprintf(tmp,"%i",skip);
  CmdLtrim(tmp);

  /* now work through remaining buffer printing out data blocks */
  block= 0;
  i= startblock;
  while (block < 6)
  {
    PrintAndLog("Block %i:", block);
    // mandemod routine needs to be split so we can call it for data
    // just print for now for debugging
    CmdManchesterDemod("i 64");
    skip= 0;
    /* look for LW before start of next block */
    for ( ; i < j - 4 ; ++i)
    {
      skip += tmpbuff[i];
      if (tmpbuff[i] >= 190 && tmpbuff[i] <= 194)
        if (tmpbuff[i+1] >= 126 && tmpbuff[i+1] <= 130)
          break;
    }
    while (GraphBuffer[skip] > low)
      ++skip;
    skip += 8;
    sprintf(tmp,"%i",skip);
    CmdLtrim(tmp);
    start += skip;
    block++;
  }
  return 0;
}

int CmdEM410xWrite(const char *Cmd)
{
  uint64_t id = 0xFFFFFFFFFFFFFFFF; // invalid id value
  int card = 0xFF; // invalid card value
	unsigned int clock = 0; // invalid clock value

	sscanf(Cmd, "%" PRIx64 " %d %d", &id, &card, &clock);

	// Check ID
	if (id == 0xFFFFFFFFFFFFFFFF) {
		PrintAndLog("Error! ID is required.\n");
		return 0;
	}
	if (id >= 0x10000000000) {
		PrintAndLog("Error! Given EM410x ID is longer than 40 bits.\n");
		return 0;
	}

	// Check Card
	if (card == 0xFF) {
		PrintAndLog("Error! Card type required.\n");
		return 0;
	}
	if (card < 0) {
		PrintAndLog("Error! Bad card type selected.\n");
		return 0;
	}

	// Check Clock
	if (card == 1)
	{
		// Default: 64
		if (clock == 0)
			clock = 64;

		// Allowed clock rates: 16, 32 and 64
		if ((clock != 16) && (clock != 32) && (clock != 64)) {
			PrintAndLog("Error! Clock rate %d not valid. Supported clock rates are 16, 32 and 64.\n", clock);
			return 0;
		}
	}
	else if (clock != 0)
	{
		PrintAndLog("Error! Clock rate is only supported on T55x7 tags.\n");
		return 0;
	}

	if (card == 1) {
		PrintAndLog("Writing %s tag with UID 0x%010" PRIx64 " (clock rate: %d)", "T55x7", id, clock);
		// NOTE: We really should pass the clock in as a separate argument, but to
		//   provide for backwards-compatibility for older firmware, and to avoid
		//   having to add another argument to CMD_EM410X_WRITE_TAG, we just store
		//   the clock rate in bits 8-15 of the card value
		card = (card & 0xFF) | (((uint64_t)clock << 8) & 0xFF00);
	}
	else if (card == 0)
		PrintAndLog("Writing %s tag with UID 0x%010" PRIx64, "T5555", id, clock);
	else {
		PrintAndLog("Error! Bad card type selected.\n");
		return 0;
	}

  UsbCommand c = {CMD_EM410X_WRITE_TAG, {card, (uint32_t)(id >> 32), (uint32_t)id}};
  SendCommand(&c);

  return 0;
}

int CmdReadWord(const char *Cmd)
{
	int Word = -1; //default to invalid word
	UsbCommand c;
  
	sscanf(Cmd, "%d", &Word);
  
	if ( (Word > 15) | (Word < 0) ) {
		PrintAndLog("Word must be between 0 and 15");
		return 1;
	}
  
	PrintAndLog("Reading word %d", Word);
  
	c.cmd = CMD_EM4X_READ_WORD;
	c.d.asBytes[0] = 0x0; //Normal mode
	c.arg[0] = 0;
	c.arg[1] = Word;
	c.arg[2] = 0;
	SendCommand(&c);
	WaitForResponse(CMD_ACK, NULL);

	uint8_t data[LF_TRACE_BUFF_SIZE] = {0x00};

	GetFromBigBuf(data,LF_TRACE_BUFF_SIZE,3560);  //3560 -- should be offset..
	WaitForResponseTimeout(CMD_ACK,NULL, 1500);

	for (int j = 0; j < LF_TRACE_BUFF_SIZE; j++) {
		GraphBuffer[j] = ((int)data[j]);
	}
	GraphTraceLen = LF_TRACE_BUFF_SIZE;
	
	uint8_t bits[1000] = {0x00};
	uint8_t * bitstream = bits;
	manchester_decode(GraphBuffer, LF_TRACE_BUFF_SIZE, bitstream);
	RepaintGraphWindow();
  return 0;
}

int CmdReadWordPWD(const char *Cmd)
{
	int Word = -1; //default to invalid word
	int Password = 0xFFFFFFFF; //default to blank password
	UsbCommand c;

	sscanf(Cmd, "%d %x", &Word, &Password);

	if ( (Word > 15) | (Word < 0) ) {
		PrintAndLog("Word must be between 0 and 15");
		return 1;
	}
  
	PrintAndLog("Reading word %d with password %08X", Word, Password);

	c.cmd = CMD_EM4X_READ_WORD;
	c.d.asBytes[0] = 0x1; //Password mode
	c.arg[0] = 0;
	c.arg[1] = Word;
	c.arg[2] = Password;
	SendCommand(&c);
	WaitForResponse(CMD_ACK, NULL);
		
	uint8_t data[LF_TRACE_BUFF_SIZE] = {0x00};

	GetFromBigBuf(data,LF_TRACE_BUFF_SIZE,3560);  //3560 -- should be offset..
	WaitForResponseTimeout(CMD_ACK,NULL, 1500);

	for (int j = 0; j < LF_TRACE_BUFF_SIZE; j++) {
		GraphBuffer[j] = ((int)data[j]);
	}
	GraphTraceLen = LF_TRACE_BUFF_SIZE;
	
	uint8_t bits[1000] = {0x00};
	uint8_t * bitstream = bits;
	
	manchester_decode(GraphBuffer, LF_TRACE_BUFF_SIZE, bitstream);
	RepaintGraphWindow();
  return 0;
}

int CmdWriteWord(const char *Cmd)
{
  int Word = 16; //default to invalid block
  int Data = 0xFFFFFFFF; //default to blank data
  UsbCommand c;
  
  sscanf(Cmd, "%x %d", &Data, &Word);
  
  if (Word > 15) {
    PrintAndLog("Word must be between 0 and 15");
    return 1;
  }
  
  PrintAndLog("Writting word %d with data %08X", Word, Data);
  
  c.cmd = CMD_EM4X_WRITE_WORD;
  c.d.asBytes[0] = 0x0; //Normal mode
  c.arg[0] = Data;
  c.arg[1] = Word;
  c.arg[2] = 0;
  SendCommand(&c);
  return 0;
}

int CmdWriteWordPWD(const char *Cmd)
{
  int Word = 8; //default to invalid word
  int Data = 0xFFFFFFFF; //default to blank data
  int Password = 0xFFFFFFFF; //default to blank password
  UsbCommand c;
  
  sscanf(Cmd, "%x %d %x", &Data, &Word, &Password);
  
  if (Word > 15) {
    PrintAndLog("Word must be between 0 and 15");
    return 1;
  }
  
  PrintAndLog("Writting word %d with data %08X and password %08X", Word, Data, Password);
  
  c.cmd = CMD_EM4X_WRITE_WORD;
  c.d.asBytes[0] = 0x1; //Password mode
  c.arg[0] = Data;
  c.arg[1] = Word;
  c.arg[2] = Password;
  SendCommand(&c);
  return 0;
}

static command_t CommandTable[] =
{
  {"help", CmdHelp, 1, "This help"},
  {"410xread", CmdEM410xRead, 1, "[clock rate] -- Extract ID from EM410x tag"},
  {"410xsim", CmdEM410xSim, 0, "<UID> -- Simulate EM410x tag"},
  {"410xwatch", CmdEM410xWatch, 0, "['h'] -- Watches for EM410x 125/134 kHz tags (option 'h' for 134)"},
  {"410xspoof", CmdEM410xWatchnSpoof, 0, "['h'] --- Watches for EM410x 125/134 kHz tags, and replays them. (option 'h' for 134)" },
  {"410xwrite", CmdEM410xWrite, 1, "<UID> <'0' T5555> <'1' T55x7> [clock rate] -- Write EM410x UID to T5555(Q5) or T55x7 tag, optionally setting clock rate"},
  {"4x50read", CmdEM4x50Read, 1, "Extract data from EM4x50 tag"},
  {"rd", CmdReadWord, 1, "<Word 1-15> -- Read EM4xxx word data"},
  {"rdpwd", CmdReadWordPWD, 1, "<Word 1-15> <Password> -- Read EM4xxx word data  in password mode "},
  {"wr", CmdWriteWord, 1, "<Data> <Word 1-15> -- Write EM4xxx word data"},
  {"wrpwd", CmdWriteWordPWD, 1, "<Data> <Word 1-15> <Password> -- Write EM4xxx word data in password mode"},
  {NULL, NULL, 0, NULL}
};

int CmdLFEM4X(const char *Cmd)
{
  CmdsParse(CommandTable, Cmd);
  return 0;
}

int CmdHelp(const char *Cmd)
{
  CmdsHelp(CommandTable);
  return 0;
}
Commit	Line	Data
a553f267	1	//-----------------------------------------------------------------------------
	2	// Copyright (C) 2010 iZsh <izsh at fail0verflow.com>
	3	//
	4	// This code is licensed to you under the terms of the GNU GPL, version 2 or,
	5	// at your option, any later version. See the LICENSE.txt file for the text of
	6	// the license.
	7	//-----------------------------------------------------------------------------
	8	// Low frequency EM4x commands
	9	//-----------------------------------------------------------------------------
	10
7fe9b0b7	11	#include <stdio.h>
9e13f875	12	#include <string.h>
ec564290	13	#include <inttypes.h>
902cb3c0	14	#include "proxmark3.h"
7fe9b0b7	15	#include "ui.h"
7fe9b0b7	16	#include "graph.h"
f38a1528	17	#include "cmdmain.h"
7fe9b0b7	18	#include "cmdparser.h"
	19	#include "cmddata.h"
	20	#include "cmdlf.h"
	21	#include "cmdlfem4x.h"
f38a1528	22	#include "util.h"
f38a1528	23	#include "data.h"
f6c18637	24	#define LF_TRACE_BUFF_SIZE 12000
f38a1528	25
f38a1528	26	char *global_em410xId;
7fe9b0b7	27
	28	static int CmdHelp(const char *Cmd);
	29
	30	/* Read the ID of an EM410x tag.
	31	* Format:
	32	* 1111 1111 1 <-- standard non-repeatable header
	33	* XXXX [row parity bit] <-- 10 rows of 5 bits for our 40 bit tag ID
	34	* ....
	35	* CCCC <-- each bit here is parity for the 10 bits above in corresponding column
	36	* 0 <-- stop bit, end of tag
	37	*/
	38	int CmdEM410xRead(const char *Cmd)
	39	{
	40	int i, j, clock, header, rows, bit, hithigh, hitlow, first, bit2idx, high, low;
	41	int parity[4];
	42	char id[11];
080ff30a	43	char id2[11];
7fe9b0b7	44	int retested = 0;
15cdabd4	45	uint8_t BitStream[MAX_GRAPH_TRACE_LEN];
7fe9b0b7	46	high = low = 0;
	47
	48	/* Detect high and lows and clock */
	49	for (i = 0; i < GraphTraceLen; i++)
	50	{
	51	if (GraphBuffer[i] > high)
	52	high = GraphBuffer[i];
	53	else if (GraphBuffer[i] < low)
	54	low = GraphBuffer[i];
	55	}
	56
	57	/* get clock */
	58	clock = GetClock(Cmd, high, 0);
	59
	60	/* parity for our 4 columns */
	61	parity[0] = parity[1] = parity[2] = parity[3] = 0;
	62	header = rows = 0;
	63
	64	/* manchester demodulate */
	65	bit = bit2idx = 0;
	66	for (i = 0; i < (int)(GraphTraceLen / clock); i++)
	67	{
	68	hithigh = 0;
	69	hitlow = 0;
	70	first = 1;
	71
	72	/* Find out if we hit both high and low peaks */
	73	for (j = 0; j < clock; j++)
	74	{
	75	if (GraphBuffer[(i * clock) + j] == high)
	76	hithigh = 1;
	77	else if (GraphBuffer[(i * clock) + j] == low)
	78	hitlow = 1;
	79
	80	/* it doesn't count if it's the first part of our read
	81	because it's really just trailing from the last sequence */
	82	if (first && (hithigh \|\| hitlow))
	83	hithigh = hitlow = 0;
	84	else
	85	first = 0;
	86
	87	if (hithigh && hitlow)
	88	break;
	89	}
	90
	91	/* If we didn't hit both high and low peaks, we had a bit transition */
	92	if (!hithigh \|\| !hitlow)
	93	bit ^= 1;
	94
	95	BitStream[bit2idx++] = bit;
	96	}
	97
	98	retest:
	99	/* We go till 5 before the graph ends because we'll get that far below */
	100	for (i = 1; i < bit2idx - 5; i++)
	101	{
	102	/* Step 2: We have our header but need our tag ID */
	103	if (header == 9 && rows < 10)
	104	{
	105	/* Confirm parity is correct */
	106	if ((BitStream[i] ^ BitStream[i+1] ^ BitStream[i+2] ^ BitStream[i+3]) == BitStream[i+4])
	107	{
	108	/* Read another byte! */
	109	sprintf(id+rows, "%x", (8 * BitStream[i]) + (4 * BitStream[i+1]) + (2 * BitStream[i+2]) + (1 * BitStream[i+3]));
cb967ea9	110	sprintf(id2+rows, "%x", (8 * BitStream[i+3]) + (4 * BitStream[i+2]) + (2 * BitStream[i+1]) + (1 * BitStream[i]));
7fe9b0b7	111	rows++;
	112
	113	/* Keep parity info */
	114	parity[0] ^= BitStream[i];
	115	parity[1] ^= BitStream[i+1];
	116	parity[2] ^= BitStream[i+2];
	117	parity[3] ^= BitStream[i+3];
	118
	119	/* Move 4 bits ahead */
	120	i += 4;
	121	}
	122
	123	/* Damn, something wrong! reset */
	124	else
	125	{
	126	PrintAndLog("Thought we had a valid tag but failed at word %d (i=%d)", rows + 1, i);
	127
	128	/* Start back rows * 5 + 9 header bits, -1 to not start at same place */
	129	i -= 9 + (5 * rows) - 5;
	130
	131	rows = header = 0;
	132	}
	133	}
	134
	135	/* Step 3: Got our 40 bits! confirm column parity */
	136	else if (rows == 10)
	137	{
	138	/* We need to make sure our 4 bits of parity are correct and we have a stop bit */
	139	if (BitStream[i] == parity[0] && BitStream[i+1] == parity[1] &&
	140	BitStream[i+2] == parity[2] && BitStream[i+3] == parity[3] &&
	141	BitStream[i+4] == 0)
	142	{
	143	/* Sweet! */
	144	PrintAndLog("EM410x Tag ID: %s", id);
cb967ea9	145	PrintAndLog("Unique Tag ID: %s", id2);
7fe9b0b7	146
f38a1528	147	global_em410xId = id;
f38a1528	148
7fe9b0b7	149	/* Stop any loops */
	150	return 1;
	151	}
	152
	153	/* Crap! Incorrect parity or no stop bit, start all over */
	154	else
	155	{
	156	rows = header = 0;
	157
	158	/* Go back 59 bits (9 header bits + 10 rows at 4+1 parity) */
	159	i -= 59;
	160	}
	161	}
	162
	163	/* Step 1: get our header */
	164	else if (header < 9)
	165	{
	166	/* Need 9 consecutive 1's */
	167	if (BitStream[i] == 1)
	168	header++;
	169
	170	/* We don't have a header, not enough consecutive 1 bits */
	171	else
	172	header = 0;
	173	}
	174	}
	175
	176	/* if we've already retested after flipping bits, return */
f38a1528	177	if (retested++){
7fe9b0b7	178	return 0;
f38a1528	179	}
7fe9b0b7	180
	181	/* if this didn't work, try flipping bits */
	182	for (i = 0; i < bit2idx; i++)
	183	BitStream[i] ^= 1;
	184
	185	goto retest;
	186	}
	187
	188	/* emulate an EM410X tag
	189	* Format:
	190	* 1111 1111 1 <-- standard non-repeatable header
	191	* XXXX [row parity bit] <-- 10 rows of 5 bits for our 40 bit tag ID
	192	* ....
	193	* CCCC <-- each bit here is parity for the 10 bits above in corresponding column
	194	* 0 <-- stop bit, end of tag
	195	*/
	196	int CmdEM410xSim(const char *Cmd)
	197	{
	198	int i, n, j, h, binary[4], parity[4];
	199
	200	/* clock is 64 in EM410x tags */
	201	int clock = 64;
	202
	203	/* clear our graph */
	204	ClearGraph(0);
	205
	206	/* write it out a few times */
	207	for (h = 0; h < 4; h++)
	208	{
	209	/* write 9 start bits */
	210	for (i = 0; i < 9; i++)
	211	AppendGraph(0, clock, 1);
	212
	213	/* for each hex char */
	214	parity[0] = parity[1] = parity[2] = parity[3] = 0;
	215	for (i = 0; i < 10; i++)
	216	{
	217	/* read each hex char */
	218	sscanf(&Cmd[i], "%1x", &n);
	219	for (j = 3; j >= 0; j--, n/= 2)
	220	binary[j] = n % 2;
	221
	222	/* append each bit */
	223	AppendGraph(0, clock, binary[0]);
	224	AppendGraph(0, clock, binary[1]);
	225	AppendGraph(0, clock, binary[2]);
	226	AppendGraph(0, clock, binary[3]);
	227
	228	/* append parity bit */
	229	AppendGraph(0, clock, binary[0] ^ binary[1] ^ binary[2] ^ binary[3]);
	230
	231	/* keep track of column parity */
	232	parity[0] ^= binary[0];
	233	parity[1] ^= binary[1];
	234	parity[2] ^= binary[2];
	235	parity[3] ^= binary[3];
	236	}
	237
	238	/* parity columns */
	239	AppendGraph(0, clock, parity[0]);
	240	AppendGraph(0, clock, parity[1]);
	241	AppendGraph(0, clock, parity[2]);
	242	AppendGraph(0, clock, parity[3]);
	243
244	/* stop bit */
245	AppendGraph(0, clock, 0);
246	}
247
248	/* modulate that biatch */
249	CmdManchesterMod("");
250
251	/* booyah! */
252	RepaintGraphWindow();
253
254	CmdLFSim("");
255	return 0;
256	}
257
c2d25819	258	/* Function is equivalent of lf read + data samples + em410xread
	259	* looped until an EM410x tag is detected
	260	*
	261	* Why is CmdSamples("16000")?
	262	* TBD: Auto-grow sample size based on detected sample rate. IE: If the
	263	* rate gets lower, then grow the number of samples
	264	* Changed by martin, 4000 x 4 = 16000,
	265	* see http://www.proxmark.org/forum/viewtopic.php?pid=7235#p7235
	266
	267	*/
7fe9b0b7	268	int CmdEM410xWatch(const char *Cmd)
7fe9b0b7	269	{
c2d25819	270	int read_h = (*Cmd == 'h');
	271	do
	272	{
	273	CmdLFRead(read_h ? "h" : "");
	274	CmdSamples("16000");
	275	} while (
f38a1528	276	!CmdEM410xRead("")
f38a1528	277	);
c2d25819	278	return 0;
f38a1528	279	}
	280
	281	int CmdEM410xWatchnSpoof(const char *Cmd)
	282	{
c2d25819	283	CmdEM410xWatch(Cmd);
f38a1528	284	PrintAndLog("# Replaying : %s",global_em410xId);
f38a1528	285	CmdEM410xSim(global_em410xId);
7fe9b0b7	286	return 0;
	287	}
	288
	289	/* Read the transmitted data of an EM4x50 tag
	290	* Format:
	291	*
	292	* XXXXXXXX [row parity bit (even)] <- 8 bits plus parity
	293	* XXXXXXXX [row parity bit (even)] <- 8 bits plus parity
	294	* XXXXXXXX [row parity bit (even)] <- 8 bits plus parity
	295	* XXXXXXXX [row parity bit (even)] <- 8 bits plus parity
	296	* CCCCCCCC <- column parity bits
	297	* 0 <- stop bit
	298	* LW <- Listen Window
	299	*
	300	* This pattern repeats for every block of data being transmitted.
	301	* Transmission starts with two Listen Windows (LW - a modulated
	302	* pattern of 320 cycles each (32/32/128/64/64)).
	303	*
	304	* Note that this data may or may not be the UID. It is whatever data
	305	* is stored in the blocks defined in the control word First and Last
	306	* Word Read values. UID is stored in block 32.
	307	*/
	308	int CmdEM4x50Read(const char *Cmd)
	309	{
31b6e9af	310	int i, j, startblock, skip, block, start, end, low, high;
7fe9b0b7	311	bool complete= false;
	312	int tmpbuff[MAX_GRAPH_TRACE_LEN / 64];
	313	char tmp[6];
	314
	315	high= low= 0;
913d23c6	316	memset(tmpbuff, 0, MAX_GRAPH_TRACE_LEN / 64);
7fe9b0b7	317
	318	/* first get high and low values */
	319	for (i = 0; i < GraphTraceLen; i++)
	320	{
	321	if (GraphBuffer[i] > high)
	322	high = GraphBuffer[i];
	323	else if (GraphBuffer[i] < low)
	324	low = GraphBuffer[i];
	325	}
	326
	327	/* populate a buffer with pulse lengths */
	328	i= 0;
	329	j= 0;
	330	while (i < GraphTraceLen)
	331	{
	332	// measure from low to low
	333	while ((GraphBuffer[i] > low) && (i<GraphTraceLen))
	334	++i;
	335	start= i;
	336	while ((GraphBuffer[i] < high) && (i<GraphTraceLen))
	337	++i;
	338	while ((GraphBuffer[i] > low) && (i<GraphTraceLen))
	339	++i;
	340	if (j>(MAX_GRAPH_TRACE_LEN/64)) {
	341	break;
	342	}
	343	tmpbuff[j++]= i - start;
	344	}
	345
	346	/* look for data start - should be 2 pairs of LW (pulses of 192,128) */
	347	start= -1;
	348	skip= 0;
	349	for (i= 0; i < j - 4 ; ++i)
	350	{
	351	skip += tmpbuff[i];
	352	if (tmpbuff[i] >= 190 && tmpbuff[i] <= 194)
	353	if (tmpbuff[i+1] >= 126 && tmpbuff[i+1] <= 130)
	354	if (tmpbuff[i+2] >= 190 && tmpbuff[i+2] <= 194)
	355	if (tmpbuff[i+3] >= 126 && tmpbuff[i+3] <= 130)
	356	{
	357	start= i + 3;
	358	break;
	359	}
	360	}
	361	startblock= i + 3;
	362
	363	/* skip over the remainder of the LW */
	364	skip += tmpbuff[i+1]+tmpbuff[i+2];
	365	while (skip < MAX_GRAPH_TRACE_LEN && GraphBuffer[skip] > low)
	366	++skip;
	367	skip += 8;
	368
	369	/* now do it again to find the end */
	370	end= start;
	371	for (i += 3; i < j - 4 ; ++i)
	372	{
	373	end += tmpbuff[i];
	374	if (tmpbuff[i] >= 190 && tmpbuff[i] <= 194)
	375	if (tmpbuff[i+1] >= 126 && tmpbuff[i+1] <= 130)
	376	if (tmpbuff[i+2] >= 190 && tmpbuff[i+2] <= 194)
	377	if (tmpbuff[i+3] >= 126 && tmpbuff[i+3] <= 130)
	378	{
	379	complete= true;
	380	break;
381	}
382	}
383
384	if (start >= 0)
385	PrintAndLog("Found data at sample: %i",skip);
386	else
387	{
388	PrintAndLog("No data found!");
389	PrintAndLog("Try again with more samples.");
390	return 0;
391	}
392
393	if (!complete)
394	{
395	PrintAndLog("*** Warning!");
396	PrintAndLog("Partial data - no end found!");
397	PrintAndLog("Try again with more samples.");
398	}
399
400	/* get rid of leading crap */
401	sprintf(tmp,"%i",skip);
402	CmdLtrim(tmp);
403
404	/* now work through remaining buffer printing out data blocks */
405	block= 0;
406	i= startblock;
407	while (block < 6)
408	{
409	PrintAndLog("Block %i:", block);
410	// mandemod routine needs to be split so we can call it for data
411	// just print for now for debugging
412	CmdManchesterDemod("i 64");
413	skip= 0;
414	/* look for LW before start of next block */
415	for ( ; i < j - 4 ; ++i)
416	{
417	skip += tmpbuff[i];
418	if (tmpbuff[i] >= 190 && tmpbuff[i] <= 194)
419	if (tmpbuff[i+1] >= 126 && tmpbuff[i+1] <= 130)
420	break;
421	}
422	while (GraphBuffer[skip] > low)
423	++skip;
424	skip += 8;
425	sprintf(tmp,"%i",skip);
426	CmdLtrim(tmp);
427	start += skip;
428	block++;
429	}
430	return 0;
431	}
432
2d4eae76	433	int CmdEM410xWrite(const char *Cmd)
2d4eae76	434	{
e67b06b7	435	uint64_t id = 0xFFFFFFFFFFFFFFFF; // invalid id value
7bb9d33e	436	int card = 0xFF; // invalid card value
e67b06b7	437	unsigned int clock = 0; // invalid clock value
	438
	439	sscanf(Cmd, "%" PRIx64 " %d %d", &id, &card, &clock);
	440
	441	// Check ID
	442	if (id == 0xFFFFFFFFFFFFFFFF) {
	443	PrintAndLog("Error! ID is required.\n");
	444	return 0;
	445	}
	446	if (id >= 0x10000000000) {
	447	PrintAndLog("Error! Given EM410x ID is longer than 40 bits.\n");
	448	return 0;
	449	}
	450
	451	// Check Card
	452	if (card == 0xFF) {
	453	PrintAndLog("Error! Card type required.\n");
	454	return 0;
	455	}
	456	if (card < 0) {
	457	PrintAndLog("Error! Bad card type selected.\n");
	458	return 0;
	459	}
	460
	461	// Check Clock
	462	if (card == 1)
	463	{
	464	// Default: 64
	465	if (clock == 0)
	466	clock = 64;
	467
	468	// Allowed clock rates: 16, 32 and 64
	469	if ((clock != 16) && (clock != 32) && (clock != 64)) {
	470	PrintAndLog("Error! Clock rate %d not valid. Supported clock rates are 16, 32 and 64.\n", clock);
	471	return 0;
	472	}
	473	}
	474	else if (clock != 0)
	475	{
	476	PrintAndLog("Error! Clock rate is only supported on T55x7 tags.\n");
	477	return 0;
	478	}
	479
	480	if (card == 1) {
	481	PrintAndLog("Writing %s tag with UID 0x%010" PRIx64 " (clock rate: %d)", "T55x7", id, clock);
	482	// NOTE: We really should pass the clock in as a separate argument, but to
	483	// provide for backwards-compatibility for older firmware, and to avoid
	484	// having to add another argument to CMD_EM410X_WRITE_TAG, we just store
	485	// the clock rate in bits 8-15 of the card value
	486	card = (card & 0xFF) \| (((uint64_t)clock << 8) & 0xFF00);
	487	}
	488	else if (card == 0)
	489	PrintAndLog("Writing %s tag with UID 0x%010" PRIx64, "T5555", id, clock);
	490	else {
	491	PrintAndLog("Error! Bad card type selected.\n");
	492	return 0;
	493	}
2d4eae76	494
2d4eae76	495	UsbCommand c = {CMD_EM410X_WRITE_TAG, {card, (uint32_t)(id >> 32), (uint32_t)id}};
	496	SendCommand(&c);
	497
	498	return 0;
	499	}
	500
54a942b0	501	int CmdReadWord(const char *Cmd)
54a942b0	502	{
f38a1528	503	int Word = -1; //default to invalid word
b44e5233	504	UsbCommand c;
54a942b0	505
b44e5233	506	sscanf(Cmd, "%d", &Word);
54a942b0	507
f38a1528	508	if ( (Word > 15) \| (Word < 0) ) {
b44e5233	509	PrintAndLog("Word must be between 0 and 15");
	510	return 1;
	511	}
54a942b0	512
b44e5233	513	PrintAndLog("Reading word %d", Word);
54a942b0	514
b44e5233	515	c.cmd = CMD_EM4X_READ_WORD;
	516	c.d.asBytes[0] = 0x0; //Normal mode
	517	c.arg[0] = 0;
	518	c.arg[1] = Word;
	519	c.arg[2] = 0;
	520	SendCommand(&c);
f38a1528	521	WaitForResponse(CMD_ACK, NULL);
f38a1528	522
f6c18637	523	uint8_t data[LF_TRACE_BUFF_SIZE] = {0x00};
f38a1528	524
b44e5233	525	GetFromBigBuf(data,LF_TRACE_BUFF_SIZE,3560); //3560 -- should be offset..
f38a1528	526	WaitForResponseTimeout(CMD_ACK,NULL, 1500);
f38a1528	527
b44e5233	528	for (int j = 0; j < LF_TRACE_BUFF_SIZE; j++) {
f6c18637	529	GraphBuffer[j] = ((int)data[j]);
f38a1528	530	}
b44e5233	531	GraphTraceLen = LF_TRACE_BUFF_SIZE;
b44e5233	532
f6c18637	533	uint8_t bits[1000] = {0x00};
b44e5233	534	uint8_t * bitstream = bits;
b44e5233	535	manchester_decode(GraphBuffer, LF_TRACE_BUFF_SIZE, bitstream);
f6c18637	536	RepaintGraphWindow();
54a942b0	537	return 0;
	538	}
	539
	540	int CmdReadWordPWD(const char *Cmd)
	541	{
f38a1528	542	int Word = -1; //default to invalid word
b44e5233	543	int Password = 0xFFFFFFFF; //default to blank password
	544	UsbCommand c;
	545
	546	sscanf(Cmd, "%d %x", &Word, &Password);
	547
f38a1528	548	if ( (Word > 15) \| (Word < 0) ) {
b44e5233	549	PrintAndLog("Word must be between 0 and 15");
	550	return 1;
	551	}
54a942b0	552
b44e5233	553	PrintAndLog("Reading word %d with password %08X", Word, Password);
	554
	555	c.cmd = CMD_EM4X_READ_WORD;
	556	c.d.asBytes[0] = 0x1; //Password mode
	557	c.arg[0] = 0;
	558	c.arg[1] = Word;
	559	c.arg[2] = Password;
	560	SendCommand(&c);
f38a1528	561	WaitForResponse(CMD_ACK, NULL);
b44e5233	562
f6c18637	563	uint8_t data[LF_TRACE_BUFF_SIZE] = {0x00};
f38a1528	564
b44e5233	565	GetFromBigBuf(data,LF_TRACE_BUFF_SIZE,3560); //3560 -- should be offset..
f38a1528	566	WaitForResponseTimeout(CMD_ACK,NULL, 1500);
f38a1528	567
b44e5233	568	for (int j = 0; j < LF_TRACE_BUFF_SIZE; j++) {
f6c18637	569	GraphBuffer[j] = ((int)data[j]);
f38a1528	570	}
b44e5233	571	GraphTraceLen = LF_TRACE_BUFF_SIZE;
b44e5233	572
f6c18637	573	uint8_t bits[1000] = {0x00};
b44e5233	574	uint8_t * bitstream = bits;
b44e5233	575
b44e5233	576	manchester_decode(GraphBuffer, LF_TRACE_BUFF_SIZE, bitstream);
f6c18637	577	RepaintGraphWindow();
54a942b0	578	return 0;
	579	}
	580
	581	int CmdWriteWord(const char *Cmd)
	582	{
	583	int Word = 16; //default to invalid block
	584	int Data = 0xFFFFFFFF; //default to blank data
	585	UsbCommand c;
	586
	587	sscanf(Cmd, "%x %d", &Data, &Word);
	588
	589	if (Word > 15) {
	590	PrintAndLog("Word must be between 0 and 15");
	591	return 1;
	592	}
	593
	594	PrintAndLog("Writting word %d with data %08X", Word, Data);
	595
	596	c.cmd = CMD_EM4X_WRITE_WORD;
	597	c.d.asBytes[0] = 0x0; //Normal mode
	598	c.arg[0] = Data;
	599	c.arg[1] = Word;
	600	c.arg[2] = 0;
	601	SendCommand(&c);
	602	return 0;
	603	}
	604
	605	int CmdWriteWordPWD(const char *Cmd)
	606	{
	607	int Word = 8; //default to invalid word
	608	int Data = 0xFFFFFFFF; //default to blank data
	609	int Password = 0xFFFFFFFF; //default to blank password
	610	UsbCommand c;
	611
	612	sscanf(Cmd, "%x %d %x", &Data, &Word, &Password);
	613
	614	if (Word > 15) {
	615	PrintAndLog("Word must be between 0 and 15");
	616	return 1;
	617	}
	618
	619	PrintAndLog("Writting word %d with data %08X and password %08X", Word, Data, Password);
	620
	621	c.cmd = CMD_EM4X_WRITE_WORD;
	622	c.d.asBytes[0] = 0x1; //Password mode
	623	c.arg[0] = Data;
	624	c.arg[1] = Word;
	625	c.arg[2] = Password;
	626	SendCommand(&c);
	627	return 0;
	628	}
	629
2d4eae76	630	static command_t CommandTable[] =
7fe9b0b7	631	{
54a942b0	632	{"help", CmdHelp, 1, "This help"},
c2d25819	633	{"410xread", CmdEM410xRead, 1, "[clock rate] -- Extract ID from EM410x tag"},
	634	{"410xsim", CmdEM410xSim, 0, "<UID> -- Simulate EM410x tag"},
	635	{"410xwatch", CmdEM410xWatch, 0, "['h'] -- Watches for EM410x 125/134 kHz tags (option 'h' for 134)"},
	636	{"410xspoof", CmdEM410xWatchnSpoof, 0, "['h'] --- Watches for EM410x 125/134 kHz tags, and replays them. (option 'h' for 134)" },
	637	{"410xwrite", CmdEM410xWrite, 1, "<UID> <'0' T5555> <'1' T55x7> [clock rate] -- Write EM410x UID to T5555(Q5) or T55x7 tag, optionally setting clock rate"},
	638	{"4x50read", CmdEM4x50Read, 1, "Extract data from EM4x50 tag"},
f38a1528	639	{"rd", CmdReadWord, 1, "<Word 1-15> -- Read EM4xxx word data"},
	640	{"rdpwd", CmdReadWordPWD, 1, "<Word 1-15> <Password> -- Read EM4xxx word data in password mode "},
	641	{"wr", CmdWriteWord, 1, "<Data> <Word 1-15> -- Write EM4xxx word data"},
	642	{"wrpwd", CmdWriteWordPWD, 1, "<Data> <Word 1-15> <Password> -- Write EM4xxx word data in password mode"},
7fe9b0b7	643	{NULL, NULL, 0, NULL}
	644	};
	645
	646	int CmdLFEM4X(const char *Cmd)
	647	{
	648	CmdsParse(CommandTable, Cmd);
	649	return 0;
	650	}
	651
	652	int CmdHelp(const char *Cmd)
	653	{
	654	CmdsHelp(CommandTable);
	655	return 0;
	656	}