[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 "proxusb.h"
#include "proxmark3.h"
#include "ui.h"
#include "graph.h"
#include "cmdparser.h"
#include "cmddata.h"
#include "cmdlf.h"
#include "cmdlfem4x.h"

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];
  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]));
        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);

        /* 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 loread + losamples + em410xread
 * looped until an EM410x tag is detected */
int CmdEM410xWatch(const char *Cmd)
{
  int read_h = (*Cmd == 'h');
  do
  {
    CmdLFRead(read_h ? "h" : "");
    // 2000 samples is OK for clock=64, but not clock=32.  Probably want
		//   8000 for clock=16.  Don't want to go too high since old HID driver
		//   is very slow
		// TBD: Auto-grow sample size based on detected sample rate.  IE: If the
		//   rate gets lower, then grow the number of samples
		CmdSamples("4000");
  } while ( ! CmdEM410xRead(""));
  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
  unsigned 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 = 16; //default to invalid word
  UsbCommand c;
  
  sscanf(Cmd, "%d", &Word);
  
  if (Word > 15) {
    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);
  return 0;
}

int CmdReadWordPWD(const char *Cmd)
{
  int Word = 16; //default to invalid word
  int Password = 0xFFFFFFFF; //default to blank password
  UsbCommand c;
  
  sscanf(Cmd, "%d %x", &Word, &Password);
  
  if (Word > 15) {
    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);
  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"},
  {"em410xread", CmdEM410xRead, 1, "[clock rate] -- Extract ID from EM410x tag"},
  {"em410xsim", CmdEM410xSim, 0, "<UID> -- Simulate EM410x tag"},
  {"em410xwatch", CmdEM410xWatch, 0, "['h'] -- Watches for EM410x 125/134 kHz tags (option 'h' for 134)"},
  {"em410xwrite", CmdEM410xWrite, 1, "<UID> <'0' T5555> <'1' T55x7> [clock rate] -- Write EM410x UID to T5555(Q5) or T55x7 tag, optionally setting clock rate"},
  {"em4x50read", CmdEM4x50Read, 1, "Extract data from EM4x50 tag"},
  {"readword", CmdReadWord, 1, "<Word> -- Read EM4xxx word data"},
  {"readwordPWD", CmdReadWordPWD, 1, "<Word> <Password> -- Read EM4xxx word data in password mode"},
  {"writeword", CmdWriteWord, 1, "<Data> <Word> -- Write EM4xxx word data"},
  {"writewordPWD", CmdWriteWordPWD, 1, "<Data> <Word> <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>
28fdb04f	14	//#include "proxusb.h"
902cb3c0	15	#include "proxmark3.h"
7fe9b0b7	16	#include "ui.h"
	17	#include "graph.h"
	18	#include "cmdparser.h"
	19	#include "cmddata.h"
	20	#include "cmdlf.h"
	21	#include "cmdlfem4x.h"
	22
	23	static int CmdHelp(const char *Cmd);
	24
	25	/* Read the ID of an EM410x tag.
	26	* Format:
	27	* 1111 1111 1 <-- standard non-repeatable header
	28	* XXXX [row parity bit] <-- 10 rows of 5 bits for our 40 bit tag ID
	29	* ....
	30	* CCCC <-- each bit here is parity for the 10 bits above in corresponding column
	31	* 0 <-- stop bit, end of tag
	32	*/
	33	int CmdEM410xRead(const char *Cmd)
	34	{
	35	int i, j, clock, header, rows, bit, hithigh, hitlow, first, bit2idx, high, low;
	36	int parity[4];
	37	char id[11];
	38	int retested = 0;
15cdabd4	39	uint8_t BitStream[MAX_GRAPH_TRACE_LEN];
7fe9b0b7	40	high = low = 0;
	41
	42	/* Detect high and lows and clock */
	43	for (i = 0; i < GraphTraceLen; i++)
	44	{
	45	if (GraphBuffer[i] > high)
	46	high = GraphBuffer[i];
	47	else if (GraphBuffer[i] < low)
	48	low = GraphBuffer[i];
	49	}
	50
	51	/* get clock */
	52	clock = GetClock(Cmd, high, 0);
	53
	54	/* parity for our 4 columns */
	55	parity[0] = parity[1] = parity[2] = parity[3] = 0;
	56	header = rows = 0;
	57
	58	/* manchester demodulate */
	59	bit = bit2idx = 0;
	60	for (i = 0; i < (int)(GraphTraceLen / clock); i++)
	61	{
	62	hithigh = 0;
	63	hitlow = 0;
	64	first = 1;
	65
	66	/* Find out if we hit both high and low peaks */
	67	for (j = 0; j < clock; j++)
	68	{
	69	if (GraphBuffer[(i * clock) + j] == high)
	70	hithigh = 1;
	71	else if (GraphBuffer[(i * clock) + j] == low)
	72	hitlow = 1;
	73
	74	/* it doesn't count if it's the first part of our read
	75	because it's really just trailing from the last sequence */
	76	if (first && (hithigh \|\| hitlow))
	77	hithigh = hitlow = 0;
	78	else
	79	first = 0;
	80
	81	if (hithigh && hitlow)
	82	break;
	83	}
	84
	85	/* If we didn't hit both high and low peaks, we had a bit transition */
	86	if (!hithigh \|\| !hitlow)
	87	bit ^= 1;
	88
	89	BitStream[bit2idx++] = bit;
	90	}
	91
	92	retest:
	93	/* We go till 5 before the graph ends because we'll get that far below */
	94	for (i = 1; i < bit2idx - 5; i++)
	95	{
	96	/* Step 2: We have our header but need our tag ID */
	97	if (header == 9 && rows < 10)
	98	{
	99	/* Confirm parity is correct */
	100	if ((BitStream[i] ^ BitStream[i+1] ^ BitStream[i+2] ^ BitStream[i+3]) == BitStream[i+4])
	101	{
	102	/* Read another byte! */
	103	sprintf(id+rows, "%x", (8 * BitStream[i]) + (4 * BitStream[i+1]) + (2 * BitStream[i+2]) + (1 * BitStream[i+3]));
104	rows++;
105
106	/* Keep parity info */
107	parity[0] ^= BitStream[i];
108	parity[1] ^= BitStream[i+1];
109	parity[2] ^= BitStream[i+2];
110	parity[3] ^= BitStream[i+3];
111
112	/* Move 4 bits ahead */
113	i += 4;
114	}
115
116	/* Damn, something wrong! reset */
117	else
118	{
119	PrintAndLog("Thought we had a valid tag but failed at word %d (i=%d)", rows + 1, i);
120
121	/* Start back rows * 5 + 9 header bits, -1 to not start at same place */
122	i -= 9 + (5 * rows) - 5;
123
124	rows = header = 0;
125	}
126	}
127
128	/* Step 3: Got our 40 bits! confirm column parity */
129	else if (rows == 10)
130	{
131	/* We need to make sure our 4 bits of parity are correct and we have a stop bit */
132	if (BitStream[i] == parity[0] && BitStream[i+1] == parity[1] &&
133	BitStream[i+2] == parity[2] && BitStream[i+3] == parity[3] &&
134	BitStream[i+4] == 0)
135	{
136	/* Sweet! */
137	PrintAndLog("EM410x Tag ID: %s", id);
138
139	/* Stop any loops */
140	return 1;
141	}
142
143	/* Crap! Incorrect parity or no stop bit, start all over */
144	else
145	{
146	rows = header = 0;
147
148	/* Go back 59 bits (9 header bits + 10 rows at 4+1 parity) */
149	i -= 59;
150	}
151	}
152
153	/* Step 1: get our header */
154	else if (header < 9)
155	{
156	/* Need 9 consecutive 1's */
157	if (BitStream[i] == 1)
158	header++;
159
160	/* We don't have a header, not enough consecutive 1 bits */
161	else
162	header = 0;
163	}
164	}
165
166	/* if we've already retested after flipping bits, return */
167	if (retested++)
168	return 0;
169
170	/* if this didn't work, try flipping bits */
171	for (i = 0; i < bit2idx; i++)
172	BitStream[i] ^= 1;
173
174	goto retest;
175	}
176
177	/* emulate an EM410X tag
178	* Format:
179	* 1111 1111 1 <-- standard non-repeatable header
180	* XXXX [row parity bit] <-- 10 rows of 5 bits for our 40 bit tag ID
181	* ....
182	* CCCC <-- each bit here is parity for the 10 bits above in corresponding column
183	* 0 <-- stop bit, end of tag
184	*/
185	int CmdEM410xSim(const char *Cmd)
186	{
187	int i, n, j, h, binary[4], parity[4];
188
189	/* clock is 64 in EM410x tags */
190	int clock = 64;
191
192	/* clear our graph */
193	ClearGraph(0);
194
195	/* write it out a few times */
196	for (h = 0; h < 4; h++)
197	{
198	/* write 9 start bits */
199	for (i = 0; i < 9; i++)
200	AppendGraph(0, clock, 1);
201
202	/* for each hex char */
203	parity[0] = parity[1] = parity[2] = parity[3] = 0;
204	for (i = 0; i < 10; i++)
205	{
206	/* read each hex char */
207	sscanf(&Cmd[i], "%1x", &n);
208	for (j = 3; j >= 0; j--, n/= 2)
209	binary[j] = n % 2;
210
211	/* append each bit */
212	AppendGraph(0, clock, binary[0]);
213	AppendGraph(0, clock, binary[1]);
214	AppendGraph(0, clock, binary[2]);
215	AppendGraph(0, clock, binary[3]);
216
217	/* append parity bit */
218	AppendGraph(0, clock, binary[0] ^ binary[1] ^ binary[2] ^ binary[3]);
219
220	/* keep track of column parity */
221	parity[0] ^= binary[0];
222	parity[1] ^= binary[1];
223	parity[2] ^= binary[2];
224	parity[3] ^= binary[3];
225	}
226
227	/* parity columns */
228	AppendGraph(0, clock, parity[0]);
229	AppendGraph(0, clock, parity[1]);
230	AppendGraph(0, clock, parity[2]);
231	AppendGraph(0, clock, parity[3]);
232
233	/* stop bit */
234	AppendGraph(0, clock, 0);
235	}
236
237	/* modulate that biatch */
238	CmdManchesterMod("");
239
240	/* booyah! */
241	RepaintGraphWindow();
242
243	CmdLFSim("");
244	return 0;
245	}
246
247	/* Function is equivalent of loread + losamples + em410xread
248	* looped until an EM410x tag is detected */
249	int CmdEM410xWatch(const char *Cmd)
250	{
e67b06b7	251	int read_h = (*Cmd == 'h');
7fe9b0b7	252	do
7fe9b0b7	253	{
e67b06b7	254	CmdLFRead(read_h ? "h" : "");
	255	// 2000 samples is OK for clock=64, but not clock=32. Probably want
	256	// 8000 for clock=16. Don't want to go too high since old HID driver
	257	// is very slow
	258	// TBD: Auto-grow sample size based on detected sample rate. IE: If the
	259	// rate gets lower, then grow the number of samples
	260	CmdSamples("4000");
ab2fd3d6	261	} while ( ! CmdEM410xRead(""));
7fe9b0b7	262	return 0;
	263	}
	264
	265	/* Read the transmitted data of an EM4x50 tag
	266	* Format:
	267	*
	268	* XXXXXXXX [row parity bit (even)] <- 8 bits plus parity
	269	* XXXXXXXX [row parity bit (even)] <- 8 bits plus parity
	270	* XXXXXXXX [row parity bit (even)] <- 8 bits plus parity
	271	* XXXXXXXX [row parity bit (even)] <- 8 bits plus parity
	272	* CCCCCCCC <- column parity bits
	273	* 0 <- stop bit
	274	* LW <- Listen Window
	275	*
	276	* This pattern repeats for every block of data being transmitted.
	277	* Transmission starts with two Listen Windows (LW - a modulated
	278	* pattern of 320 cycles each (32/32/128/64/64)).
	279	*
	280	* Note that this data may or may not be the UID. It is whatever data
	281	* is stored in the blocks defined in the control word First and Last
	282	* Word Read values. UID is stored in block 32.
	283	*/
	284	int CmdEM4x50Read(const char *Cmd)
	285	{
31b6e9af	286	int i, j, startblock, skip, block, start, end, low, high;
7fe9b0b7	287	bool complete= false;
	288	int tmpbuff[MAX_GRAPH_TRACE_LEN / 64];
	289	char tmp[6];
	290
	291	high= low= 0;
913d23c6	292	memset(tmpbuff, 0, MAX_GRAPH_TRACE_LEN / 64);
7fe9b0b7	293
	294	/* first get high and low values */
	295	for (i = 0; i < GraphTraceLen; i++)
	296	{
	297	if (GraphBuffer[i] > high)
	298	high = GraphBuffer[i];
	299	else if (GraphBuffer[i] < low)
	300	low = GraphBuffer[i];
	301	}
	302
	303	/* populate a buffer with pulse lengths */
	304	i= 0;
	305	j= 0;
	306	while (i < GraphTraceLen)
	307	{
	308	// measure from low to low
	309	while ((GraphBuffer[i] > low) && (i<GraphTraceLen))
	310	++i;
	311	start= i;
	312	while ((GraphBuffer[i] < high) && (i<GraphTraceLen))
	313	++i;
	314	while ((GraphBuffer[i] > low) && (i<GraphTraceLen))
	315	++i;
	316	if (j>(MAX_GRAPH_TRACE_LEN/64)) {
	317	break;
	318	}
	319	tmpbuff[j++]= i - start;
	320	}
	321
	322	/* look for data start - should be 2 pairs of LW (pulses of 192,128) */
	323	start= -1;
	324	skip= 0;
	325	for (i= 0; i < j - 4 ; ++i)
	326	{
	327	skip += tmpbuff[i];
	328	if (tmpbuff[i] >= 190 && tmpbuff[i] <= 194)
	329	if (tmpbuff[i+1] >= 126 && tmpbuff[i+1] <= 130)
	330	if (tmpbuff[i+2] >= 190 && tmpbuff[i+2] <= 194)
	331	if (tmpbuff[i+3] >= 126 && tmpbuff[i+3] <= 130)
	332	{
	333	start= i + 3;
	334	break;
	335	}
	336	}
	337	startblock= i + 3;
	338
	339	/* skip over the remainder of the LW */
	340	skip += tmpbuff[i+1]+tmpbuff[i+2];
	341	while (skip < MAX_GRAPH_TRACE_LEN && GraphBuffer[skip] > low)
	342	++skip;
	343	skip += 8;
	344
	345	/* now do it again to find the end */
	346	end= start;
	347	for (i += 3; i < j - 4 ; ++i)
	348	{
	349	end += tmpbuff[i];
	350	if (tmpbuff[i] >= 190 && tmpbuff[i] <= 194)
	351	if (tmpbuff[i+1] >= 126 && tmpbuff[i+1] <= 130)
	352	if (tmpbuff[i+2] >= 190 && tmpbuff[i+2] <= 194)
	353	if (tmpbuff[i+3] >= 126 && tmpbuff[i+3] <= 130)
	354	{
	355	complete= true;
	356	break;
357	}
358	}
359
360	if (start >= 0)
361	PrintAndLog("Found data at sample: %i",skip);
362	else
363	{
364	PrintAndLog("No data found!");
365	PrintAndLog("Try again with more samples.");
366	return 0;
367	}
368
369	if (!complete)
370	{
371	PrintAndLog("*** Warning!");
372	PrintAndLog("Partial data - no end found!");
373	PrintAndLog("Try again with more samples.");
374	}
375
376	/* get rid of leading crap */
377	sprintf(tmp,"%i",skip);
378	CmdLtrim(tmp);
379
380	/* now work through remaining buffer printing out data blocks */
381	block= 0;
382	i= startblock;
383	while (block < 6)
384	{
385	PrintAndLog("Block %i:", block);
386	// mandemod routine needs to be split so we can call it for data
387	// just print for now for debugging
388	CmdManchesterDemod("i 64");
389	skip= 0;
390	/* look for LW before start of next block */
391	for ( ; i < j - 4 ; ++i)
392	{
393	skip += tmpbuff[i];
394	if (tmpbuff[i] >= 190 && tmpbuff[i] <= 194)
395	if (tmpbuff[i+1] >= 126 && tmpbuff[i+1] <= 130)
396	break;
397	}
398	while (GraphBuffer[skip] > low)
399	++skip;
400	skip += 8;
401	sprintf(tmp,"%i",skip);
402	CmdLtrim(tmp);
403	start += skip;
404	block++;
405	}
406	return 0;
407	}
408
2d4eae76	409	int CmdEM410xWrite(const char *Cmd)
2d4eae76	410	{
e67b06b7	411	uint64_t id = 0xFFFFFFFFFFFFFFFF; // invalid id value
	412	unsigned int card = 0xFF; // invalid card value
	413	unsigned int clock = 0; // invalid clock value
	414
	415	sscanf(Cmd, "%" PRIx64 " %d %d", &id, &card, &clock);
	416
	417	// Check ID
	418	if (id == 0xFFFFFFFFFFFFFFFF) {
	419	PrintAndLog("Error! ID is required.\n");
	420	return 0;
	421	}
	422	if (id >= 0x10000000000) {
	423	PrintAndLog("Error! Given EM410x ID is longer than 40 bits.\n");
	424	return 0;
	425	}
	426
	427	// Check Card
	428	if (card == 0xFF) {
	429	PrintAndLog("Error! Card type required.\n");
	430	return 0;
	431	}
	432	if (card < 0) {
	433	PrintAndLog("Error! Bad card type selected.\n");
	434	return 0;
	435	}
	436
	437	// Check Clock
	438	if (card == 1)
	439	{
	440	// Default: 64
	441	if (clock == 0)
	442	clock = 64;
	443
	444	// Allowed clock rates: 16, 32 and 64
	445	if ((clock != 16) && (clock != 32) && (clock != 64)) {
	446	PrintAndLog("Error! Clock rate %d not valid. Supported clock rates are 16, 32 and 64.\n", clock);
	447	return 0;
	448	}
	449	}
	450	else if (clock != 0)
	451	{
	452	PrintAndLog("Error! Clock rate is only supported on T55x7 tags.\n");
	453	return 0;
	454	}
	455
	456	if (card == 1) {
	457	PrintAndLog("Writing %s tag with UID 0x%010" PRIx64 " (clock rate: %d)", "T55x7", id, clock);
	458	// NOTE: We really should pass the clock in as a separate argument, but to
	459	// provide for backwards-compatibility for older firmware, and to avoid
	460	// having to add another argument to CMD_EM410X_WRITE_TAG, we just store
	461	// the clock rate in bits 8-15 of the card value
	462	card = (card & 0xFF) \| (((uint64_t)clock << 8) & 0xFF00);
	463	}
	464	else if (card == 0)
	465	PrintAndLog("Writing %s tag with UID 0x%010" PRIx64, "T5555", id, clock);
	466	else {
	467	PrintAndLog("Error! Bad card type selected.\n");
	468	return 0;
	469	}
2d4eae76	470
2d4eae76	471	UsbCommand c = {CMD_EM410X_WRITE_TAG, {card, (uint32_t)(id >> 32), (uint32_t)id}};
	472	SendCommand(&c);
	473
	474	return 0;
	475	}
	476
54a942b0	477	int CmdReadWord(const char *Cmd)
	478	{
	479	int Word = 16; //default to invalid word
	480	UsbCommand c;
	481
	482	sscanf(Cmd, "%d", &Word);
	483
	484	if (Word > 15) {
	485	PrintAndLog("Word must be between 0 and 15");
	486	return 1;
	487	}
	488
	489	PrintAndLog("Reading word %d", Word);
	490
	491	c.cmd = CMD_EM4X_READ_WORD;
	492	c.d.asBytes[0] = 0x0; //Normal mode
	493	c.arg[0] = 0;
	494	c.arg[1] = Word;
	495	c.arg[2] = 0;
	496	SendCommand(&c);
	497	return 0;
	498	}
	499
	500	int CmdReadWordPWD(const char *Cmd)
	501	{
	502	int Word = 16; //default to invalid word
	503	int Password = 0xFFFFFFFF; //default to blank password
	504	UsbCommand c;
	505
	506	sscanf(Cmd, "%d %x", &Word, &Password);
	507
	508	if (Word > 15) {
	509	PrintAndLog("Word must be between 0 and 15");
	510	return 1;
	511	}
	512
	513	PrintAndLog("Reading word %d with password %08X", Word, Password);
	514
	515	c.cmd = CMD_EM4X_READ_WORD;
	516	c.d.asBytes[0] = 0x1; //Password mode
	517	c.arg[0] = 0;
	518	c.arg[1] = Word;
	519	c.arg[2] = Password;
	520	SendCommand(&c);
	521	return 0;
	522	}
	523
	524	int CmdWriteWord(const char *Cmd)
	525	{
	526	int Word = 16; //default to invalid block
	527	int Data = 0xFFFFFFFF; //default to blank data
	528	UsbCommand c;
	529
	530	sscanf(Cmd, "%x %d", &Data, &Word);
	531
	532	if (Word > 15) {
	533	PrintAndLog("Word must be between 0 and 15");
	534	return 1;
	535	}
	536
	537	PrintAndLog("Writting word %d with data %08X", Word, Data);
	538
	539	c.cmd = CMD_EM4X_WRITE_WORD;
	540	c.d.asBytes[0] = 0x0; //Normal mode
541	c.arg[0] = Data;
542	c.arg[1] = Word;
543	c.arg[2] = 0;
544	SendCommand(&c);
545	return 0;
546	}
547
548	int CmdWriteWordPWD(const char *Cmd)
549	{
550	int Word = 8; //default to invalid word
551	int Data = 0xFFFFFFFF; //default to blank data
552	int Password = 0xFFFFFFFF; //default to blank password
553	UsbCommand c;
554
555	sscanf(Cmd, "%x %d %x", &Data, &Word, &Password);
556
557	if (Word > 15) {
558	PrintAndLog("Word must be between 0 and 15");
559	return 1;
560	}
561
562	PrintAndLog("Writting word %d with data %08X and password %08X", Word, Data, Password);
563
564	c.cmd = CMD_EM4X_WRITE_WORD;
565	c.d.asBytes[0] = 0x1; //Password mode
566	c.arg[0] = Data;
567	c.arg[1] = Word;
568	c.arg[2] = Password;
569	SendCommand(&c);
570	return 0;
571	}
572
573
574
2d4eae76	575	static command_t CommandTable[] =
7fe9b0b7	576	{
54a942b0	577	{"help", CmdHelp, 1, "This help"},
	578	{"em410xread", CmdEM410xRead, 1, "[clock rate] -- Extract ID from EM410x tag"},
	579	{"em410xsim", CmdEM410xSim, 0, "<UID> -- Simulate EM410x tag"},
e67b06b7	580	{"em410xwatch", CmdEM410xWatch, 0, "['h'] -- Watches for EM410x 125/134 kHz tags (option 'h' for 134)"},
e67b06b7	581	{"em410xwrite", CmdEM410xWrite, 1, "<UID> <'0' T5555> <'1' T55x7> [clock rate] -- Write EM410x UID to T5555(Q5) or T55x7 tag, optionally setting clock rate"},
54a942b0	582	{"em4x50read", CmdEM4x50Read, 1, "Extract data from EM4x50 tag"},
	583	{"readword", CmdReadWord, 1, "<Word> -- Read EM4xxx word data"},
	584	{"readwordPWD", CmdReadWordPWD, 1, "<Word> <Password> -- Read EM4xxx word data in password mode"},
	585	{"writeword", CmdWriteWord, 1, "<Data> <Word> -- Write EM4xxx word data"},
	586	{"writewordPWD", CmdWriteWordPWD, 1, "<Data> <Word> <Password> -- Write EM4xxx word data in password mode"},
7fe9b0b7	587	{NULL, NULL, 0, NULL}
	588	};
	589
	590	int CmdLFEM4X(const char *Cmd)
	591	{
	592	CmdsParse(CommandTable, Cmd);
	593	return 0;
	594	}
	595
	596	int CmdHelp(const char *Cmd)
	597	{
	598	CmdsHelp(CommandTable);
	599	return 0;
	600	}