client/src/cmdlfzx8211.c

   1 //-----------------------------------------------------------------------------
   2 // Copyright (C) Proxmark3 contributors. See AUTHORS.md for details.
   3 //
   4 // This program is free software: you can redistribute it and/or modify
   5 // it under the terms of the GNU General Public License as published by
   6 // the Free Software Foundation, either version 3 of the License, or
   7 // (at your option) any later version.
   8 //
   9 // This program is distributed in the hope that it will be useful,
  10 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 // GNU General Public License for more details.
  13 //
  14 // See LICENSE.txt for the text of the license.
  15 //-----------------------------------------------------------------------------
  16 // Low frequency ZX8211 tag commands
  17 //-----------------------------------------------------------------------------
  18
  19 #include "cmdlfzx8211.h"
  20 #include <string.h>
  21 #include <ctype.h>
  22 #include <stdlib.h>
  23 #include <inttypes.h>
  24 #include <stdio.h>
  25 #include "commonutil.h"    // ARRAYLEN
  26 #include "common.h"
  27 #include "cmdparser.h"     // command_t
  28 #include "comms.h"
  29 #include "ui.h"
  30 #include "graph.h"
  31 #include "cmddata.h"
  32 #include "cmdlf.h"
  33 #include "protocols.h"     // for T55xx config register definitions
  34 #include "lfdemod.h"       // parityTest
  35 #include "cmdlft55xx.h"    // write verify
  36 #include "cliparser.h"
  37 #include "zx8211.h"
  38
  39 static int CmdHelp(const char *Cmd);
  40
  41 // see ASKDemod for what args are accepted
  42 int demodzx(bool verbose) {
  43     (void) verbose; // unused so far
  44     buffer_savestate_t saveState = save_bufferS32(g_GraphBuffer, g_GraphTraceLen);
  45     saveState.offset = g_GridOffset;
  46
  47     // CmdAskEdgeDetect("");
  48
  49     // ASK / Manchester
  50     bool st = true;
  51     if (ASKDemod_ext(64, 0, 0, 0, false, false, false, 1, &st) != PM3_SUCCESS) {
  52         PrintAndLogEx(DEBUG, "DEBUG: Error - ZX: ASK/Manchester Demod failed");
  53         restore_bufferS32(saveState, g_GraphBuffer);
  54         g_GridOffset = saveState.offset;
  55         return PM3_ESOFT;
  56     }
  57     size_t size = g_DemodBufferLen;
  58     int ans = detectzx(g_DemodBuffer, &size);
  59     if (ans < 0) {
  60         if (ans == -1)
  61             PrintAndLogEx(DEBUG, "DEBUG: Error - ZX: too few bits found");
  62         else if (ans == -2)
  63             PrintAndLogEx(DEBUG, "DEBUG: Error - ZX: preamble not found");
  64         else if (ans == -3)
  65             PrintAndLogEx(DEBUG, "DEBUG: Error - ZX: Size not correct: %zu", size);
  66         else
  67             PrintAndLogEx(DEBUG, "DEBUG: Error - ZX: ans: %d", ans);
  68
  69         restore_bufferS32(saveState, g_GraphBuffer);
  70         g_GridOffset = saveState.offset;
  71         return PM3_ESOFT;
  72     }
  73     setDemodBuff(g_DemodBuffer, 96, ans);
  74     setClockGrid(g_DemodClock, g_DemodStartIdx + (ans * g_DemodClock));
  75
  76     // got a good demod
  77     uint32_t raw1 = bytebits_to_byte(g_DemodBuffer, 32);
  78
  79     // chksum
  80
  81     // test checksums
  82
  83     PrintAndLogEx(SUCCESS, "ZX8211 - Card " _GREEN_("%u"), raw1);
  84     return PM3_SUCCESS;
  85 }
  86
  87 static int lf_Zx_read(void) {
  88
  89     PacketResponseNG resp;
  90     clearCommandBuffer();
  91
  92     SendCommandNG(CMD_LF_ZX_READ, NULL, 0);
  93
  94     if (WaitForResponseTimeout(CMD_LF_ZX_READ, &resp, 1000) == false) {
  95         PrintAndLogEx(ERR, "Error occurred, device did not respond during read operation.");
  96         return PM3_ETIMEOUT;
  97     }
  98
  99     return PM3_SUCCESS;
 100 }
 101
 102 static int CmdZxDemod(const char *Cmd) {
 103     CLIParserContext *ctx;
 104     CLIParserInit(&ctx, "lf zx demod",
 105                   "Try to find zx8211 preamble, if found decode / descramble data",
 106                   "lf zx demod"
 107                  );
 108
 109     void *argtable[] = {
 110         arg_param_begin,
 111         arg_param_end
 112     };
 113     CLIExecWithReturn(ctx, Cmd, argtable, true);
 114     CLIParserFree(ctx);
 115     return demodzx(true);
 116 }
 117
 118 static int CmdzxReader(const char *Cmd) {
 119     CLIParserContext *ctx;
 120     CLIParserInit(&ctx, "lf zx reader",
 121                   "read a zx tag",
 122                   "lf zx reader -@   -> continuous reader mode"
 123                  );
 124
 125     void *argtable[] = {
 126         arg_param_begin,
 127         arg_lit0("@", NULL, "optional - continuous reader mode"),
 128         arg_param_end
 129     };
 130     CLIExecWithReturn(ctx, Cmd, argtable, true);
 131     bool cm = arg_get_lit(ctx, 1);
 132     CLIParserFree(ctx);
 133
 134     if (cm) {
 135         PrintAndLogEx(INFO, "Press " _GREEN_("<Enter>") " to exit");
 136     }
 137
 138     do {
 139         lf_Zx_read();
 140         demodzx(!cm);
 141     } while (cm && !kbd_enter_pressed());
 142     return PM3_SUCCESS;
 143 }
 144
 145
 146 static command_t CommandTable[] = {
 147     {"help",    CmdHelp,         AlwaysAvailable, "This help"},
 148     {"demod",   CmdZxDemod,      AlwaysAvailable, "demodulate an ZX 8211 tag from the GraphBuffer"},
 149     {"reader",  CmdzxReader,     IfPm3Lf,         "attempt to read and extract tag data"},
 150     {NULL, NULL, NULL, NULL}
 151 };
 152
 153 static int CmdHelp(const char *Cmd) {
 154     (void)Cmd; // Cmd is not used so far
 155     CmdsHelp(CommandTable);
 156     return PM3_SUCCESS;
 157 }
 158
 159 int CmdLFZx8211(const char *Cmd) {
 160     clearCommandBuffer();
 161     return CmdsParse(CommandTable, Cmd);
 162 }
 163
 164 int detectzx(uint8_t *dest, size_t *size) {
 165     if (*size < 96) return -1; // make sure buffer has data
 166     size_t startIdx = 0;
 167     uint8_t preamble[] = {0, 1, 0, 1, 0, 1, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 1, 0};
 168     if (!preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx))
 169         return -2; // preamble not found
 170     if (*size != 96) return -3; // wrong demoded size
 171     // return start position
 172     return (int)startIdx;
 173 }
 174
 175