client/src/cmdlfdestron.c

   1 //-----------------------------------------------------------------------------
   2 //
   3 // This code is licensed to you under the terms of the GNU GPL, version 2 or,
   4 // at your option, any later version. See the LICENSE.txt file for the text of
   5 // the license.
   6 //-----------------------------------------------------------------------------
   7 // Low frequency FDX-A FECAVA Destron tag commands
   8 //-----------------------------------------------------------------------------
   9 #include "cmdlfdestron.h"
  10 #include <ctype.h>        // tolower
  11 #include <string.h>       // memcpy
  12 #include "commonutil.h"   // ARRAYLEN
  13 #include "common.h"
  14 #include "cmdparser.h"    // command_t
  15 #include "comms.h"
  16 #include "ui.h"
  17 #include "cmddata.h"
  18 #include "cmdlf.h"
  19 #include "lfdemod.h"      // preamble test
  20 #include "protocols.h"    // t55xx defines
  21 #include "cmdlft55xx.h"   // clone..
  22 #include "cmdlf.h"        // cmdlfconfig
  23 #include "parity.h"
  24 #include "cliparser.h"    // cli parse input
  25 #include "cmdlfem4x05.h"  // EM defines
  26
  27 #define DESTRON_FRAME_SIZE 96
  28 #define DESTRON_PREAMBLE_SIZE 16
  29
  30 static int CmdHelp(const char *Cmd);
  31
  32 int demodDestron(bool verbose) {
  33     (void) verbose; // unused so far
  34     //PSK1
  35     if (FSKrawDemod(0, 0, 0, 0, false) != PM3_SUCCESS) {
  36         PrintAndLogEx(DEBUG, "DEBUG: Error - Destron: FSK Demod failed");
  37         return PM3_ESOFT;
  38     }
  39
  40     size_t size = DemodBufferLen;
  41     int ans = detectDestron(DemodBuffer, &size);
  42     if (ans < 0) {
  43         if (ans == -1)
  44             PrintAndLogEx(DEBUG, "DEBUG: Error - Destron: too few bits found");
  45         else if (ans == -2)
  46             PrintAndLogEx(DEBUG, "DEBUG: Error - Destron: preamble not found");
  47         else if (ans == -3)
  48             PrintAndLogEx(DEBUG, "DEBUG: Error - Destron: Size not correct: %zu", size);
  49         else
  50             PrintAndLogEx(DEBUG, "DEBUG: Error - Destron: ans: %d", ans);
  51
  52         return PM3_ESOFT;
  53     }
  54
  55     setDemodBuff(DemodBuffer, DESTRON_FRAME_SIZE, ans);
  56     setClockGrid(g_DemodClock, g_DemodStartIdx + (ans * g_DemodClock));
  57
  58     uint8_t bits[DESTRON_FRAME_SIZE - DESTRON_PREAMBLE_SIZE] = {0};
  59     size_t bitlen = DESTRON_FRAME_SIZE - DESTRON_PREAMBLE_SIZE;
  60     memcpy(bits, DemodBuffer + DESTRON_PREAMBLE_SIZE, DESTRON_FRAME_SIZE - DESTRON_PREAMBLE_SIZE);
  61
  62     uint8_t alignPos = 0;
  63     uint16_t errCnt = manrawdecode(bits, &bitlen, 0, &alignPos);
  64     if (errCnt > 0) {
  65         PrintAndLogEx(DEBUG, "DEBUG: Error - Destron: Manchester decoding errors: %d", ans);
  66         return PM3_ESOFT;
  67     }
  68
  69     uint8_t data[5] = {0};
  70     uint8_t parity_err = 0;
  71     for (int i = 0; i < sizeof(data); i++) {
  72         data[i] = bytebits_to_byte(bits + i * 8, 8);
  73         parity_err += oddparity8(data[i]);
  74         data[i] &= 0x7F;
  75     }
  76     if (parity_err > 0) {
  77         PrintAndLogEx(DEBUG, "DEBUG: Error - Destron: parity errors: %d", parity_err);
  78         return PM3_ESOFT;
  79     }
  80     PrintAndLogEx(SUCCESS, "FDX-A FECAVA Destron: " _GREEN_("%s"), sprint_hex_inrow(data, 5));
  81     return PM3_SUCCESS;
  82 }
  83
  84 static int CmdDestronDemod(const char *Cmd) {
  85     CLIParserContext *ctx;
  86     CLIParserInit(&ctx, "lf destron demod",
  87                   "Try to find Destron preamble, if found decode / descramble data",
  88                   "lf destron demod"
  89                  );
  90
  91     void *argtable[] = {
  92         arg_param_begin,
  93         arg_param_end
  94     };
  95     CLIExecWithReturn(ctx, Cmd, argtable, true);
  96     CLIParserFree(ctx);
  97     return demodDestron(true);
  98 }
  99
 100 static int CmdDestronReader(const char *Cmd) {
 101     CLIParserContext *ctx;
 102     CLIParserInit(&ctx, "lf destron reader",
 103                   "read a Destron tag",
 104                   "lf destron reader -@   -> continuous reader mode"
 105                  );
 106
 107     void *argtable[] = {
 108         arg_param_begin,
 109         arg_lit0("@", NULL, "optional - continuous reader mode"),
 110         arg_param_end
 111     };
 112     CLIExecWithReturn(ctx, Cmd, argtable, true);
 113     bool cm = arg_get_lit(ctx, 1);
 114     CLIParserFree(ctx);
 115
 116     if (cm) {
 117         PrintAndLogEx(INFO, "Press " _GREEN_("<Enter>") " to exit");
 118     }
 119
 120     do {
 121         lf_read(false, 16000);
 122         demodDestron(!cm);
 123     } while (cm && !kbd_enter_pressed());
 124
 125     return PM3_SUCCESS;
 126 }
 127
 128 static int CmdDestronClone(const char *Cmd) {
 129     CLIParserContext *ctx;
 130     CLIParserInit(&ctx, "lf destron clone",
 131                   "clone a Destron tag to a T55x7, Q5/T5555 or EM4305/4469 tag.",
 132                   "lf destron clone --uid 1A2B3C4D5E\n"
 133                   "lf destron clone --q5  --uid 1A2B3C4D5E   -> encode for Q5/T5555 tag\n"
 134                   "lf destron clone --em  --uid 1A2B3C4D5E   -> encode for EM4305/4469"
 135                  );
 136
 137     void *argtable[] = {
 138         arg_param_begin,
 139         arg_strx1("u", "uid", "<hex>", "5 bytes max"),
 140         arg_lit0(NULL, "q5", "optional - specify writing to Q5/T5555 tag"),
 141         arg_lit0(NULL, "em", "optional - specify writing to EM4305/4469 tag"),
 142         arg_param_end
 143     };
 144
 145     //TODO add selection of chip for Q5 or T55x7
 146     CLIExecWithReturn(ctx, Cmd, argtable, false);
 147
 148     uint8_t data[8];
 149     int datalen = 0;
 150     CLIGetHexWithReturn(ctx, 1, data, &datalen);
 151     bool q5 = arg_get_lit(ctx, 2);
 152     bool em = arg_get_lit(ctx, 3);
 153     CLIParserFree(ctx);
 154
 155     if (q5 && em) {
 156         PrintAndLogEx(FAILED, "Can't specify both Q5 and EM4305 at the same time");
 157         return PM3_EINVARG;
 158     }
 159
 160     if (datalen > 5) {
 161         PrintAndLogEx(FAILED, "Uid is max 5 bytes. (got %u)", datalen);
 162         return PM3_EINVARG;
 163     }
 164
 165     uint32_t blocks[4] = {0};
 166     blocks[0] = T55x7_BITRATE_RF_50 | T55x7_MODULATION_FSK2 | 3 << T55x7_MAXBLOCK_SHIFT;
 167     char cardtype[16] = {"T55x7"};
 168     // Q5
 169     if (q5) {
 170         blocks[0] = T5555_FIXED | T5555_MODULATION_FSK2  | T5555_SET_BITRATE(50) | 3 << T5555_MAXBLOCK_SHIFT;
 171         snprintf(cardtype, sizeof(cardtype), "Q5/T5555");
 172     }
 173
 174     // EM4305
 175     if (em) {
 176         blocks[0] = EM4305_DESTRON_CONFIG_BLOCK;
 177         snprintf(cardtype, sizeof(cardtype), "EM4305/4469");
 178     }
 179
 180     uint8_t data_ex[12 + 24] = {0}; // ManchesterEncode need extra room
 181     for (int i = 0; i < datalen; i++) {
 182         data_ex[i + 1] = ~(data [i] | (oddparity8(data[i]) << 7));
 183     }
 184
 185     // manchester encode it
 186     for (int i = 0; i < 3; i++) {
 187         blocks[i + 1] = manchesterEncode2Bytes((data_ex[i * 2] << 8) + data_ex[i * 2 + 1]);
 188     }
 189     // inject preamble
 190     blocks[1] = (blocks[1] & 0xFFFF) | 0xAAE20000;
 191
 192     PrintAndLogEx(INFO, "Preparing to clone Destron tag to " _YELLOW_("%s") " with ID: " _YELLOW_("%s")
 193                   , cardtype
 194                   , sprint_hex_inrow(data, datalen)
 195                  );
 196
 197
 198     print_blocks(blocks, ARRAYLEN(blocks));
 199     int res;
 200     if (em) {
 201         res = em4x05_clone_tag(blocks, ARRAYLEN(blocks), 0, false);
 202     } else {
 203         res = clone_t55xx_tag(blocks, ARRAYLEN(blocks));
 204     }
 205     PrintAndLogEx(SUCCESS, "Done");
 206     PrintAndLogEx(HINT, "Hint: try " _YELLOW_("`lf destron reader`") " to verify");
 207     return res;
 208 }
 209
 210 static int CmdDestronSim(const char *Cmd) {
 211     CLIParserContext *ctx;
 212     CLIParserInit(&ctx, "lf destron sim",
 213                   "Try to find Destron preamble, if found decode / descramble data",
 214                   "lf destron sim"
 215                  );
 216
 217     void *argtable[] = {
 218         arg_param_begin,
 219         arg_param_end
 220     };
 221     CLIExecWithReturn(ctx, Cmd, argtable, true);
 222     CLIParserFree(ctx);
 223     PrintAndLogEx(INFO, " To be implemented, feel free to contribute!");
 224     return PM3_SUCCESS;
 225 }
 226
 227 static command_t CommandTable[] = {
 228     {"help",   CmdHelp,          AlwaysAvailable, "This help"},
 229     {"demod",  CmdDestronDemod,  AlwaysAvailable, "demodulate an Destron tag from the GraphBuffer"},
 230     {"reader", CmdDestronReader, IfPm3Lf,         "attempt to read and extract tag data"},
 231     {"clone",  CmdDestronClone,  IfPm3Lf,         "clone Destron tag to T55x7"},
 232     {"sim",    CmdDestronSim,    IfPm3Lf,         "simulate Destron tag"},
 233     {NULL, NULL, NULL, NULL}
 234 };
 235
 236 static int CmdHelp(const char *Cmd) {
 237     (void)Cmd; // Cmd is not used so far
 238     CmdsHelp(CommandTable);
 239     return PM3_SUCCESS;
 240 }
 241
 242 int CmdLFDestron(const char *Cmd) {
 243     clearCommandBuffer();
 244     return CmdsParse(CommandTable, Cmd);
 245 }
 246
 247 // find Destron preamble in already demoded data
 248 int detectDestron(uint8_t *dest, size_t *size) {
 249
 250     //make sure buffer has data
 251     if (*size < 64)
 252         return -1;
 253
 254     size_t found_size = *size;
 255     size_t start_idx = 0;
 256
 257     uint8_t preamble[DESTRON_PREAMBLE_SIZE] =  {1, 0, 1, 0, 1, 0, 1, 0, 1, 1, 1, 0, 0, 0, 1, 0};
 258
 259     // preamble not found
 260     if (!preambleSearch(dest, preamble, sizeof(preamble), &found_size, &start_idx)) {
 261         return -2;
 262     }
 263     PrintAndLogEx(DEBUG, "DEBUG: detectDestron FSK found preamble");
 264
 265     *size = found_size;
 266     // wrong demoded size
 267     if (*size != 96)
 268         return -3;
 269
 270     return (int)start_idx;
 271 }
 272
 273 int readDestronUid(void) {
 274     return (CmdDestronReader("") == PM3_SUCCESS);
 275 }