cvs.zerfleddert.de Git - proxmark3-svn/blob - client/cmdhf14a.c

   1 //-----------------------------------------------------------------------------
   2 // 2011, Merlok
   3 // Copyright (C) 2010 iZsh <izsh at fail0verflow.com>, Hagen Fritsch
   4 //
   5 // This code is licensed to you under the terms of the GNU GPL, version 2 or,
   6 // at your option, any later version. See the LICENSE.txt file for the text of
   7 // the license.
   8 //-----------------------------------------------------------------------------
   9 // High frequency ISO14443A commands
  10 //-----------------------------------------------------------------------------
  11
  12 #include <stdio.h>
  13 #include <stdlib.h>
  14 #include <string.h>
  15 #include <conio.h>
  16 #include "util.h"
  17 #include "iso14443crc.h"
  18 #include "data.h"
  19 #include "proxusb.h"
  20 #include "ui.h"
  21 #include "cmdparser.h"
  22 #include "cmdhf14a.h"
  23 #include "common.h"
  24 #include "cmdmain.h"
  25 #include "nonce2key/nonce2key.h"
  26 #include "nonce2key/crapto1.h"
  27
  28 static int CmdHelp(const char *Cmd);
  29
  30 int CmdHF14AList(const char *Cmd)
  31 {
  32   uint8_t got[1920];
  33   GetFromBigBuf(got, sizeof(got));
  34
  35   PrintAndLog("recorded activity:");
  36   PrintAndLog(" ETU     :rssi: who bytes");
  37   PrintAndLog("---------+----+----+-----------");
  38
  39   int i = 0;
  40   int prev = -1;
  41
  42   for (;;) {
  43     if(i >= 1900) {
  44       break;
  45     }
  46
  47     bool isResponse;
  48     int timestamp = *((uint32_t *)(got+i));
  49     if (timestamp & 0x80000000) {
  50       timestamp &= 0x7fffffff;
  51       isResponse = 1;
  52     } else {
  53       isResponse = 0;
  54     }
  55
  56     int metric = 0;
  57     int parityBits = *((uint32_t *)(got+i+4));
  58     // 4 bytes of additional information...
  59     // maximum of 32 additional parity bit information
  60     //
  61     // TODO:
  62     // at each quarter bit period we can send power level (16 levels)
  63     // or each half bit period in 256 levels.
  64
  65
  66     int len = got[i+8];
  67
  68     if (len > 100) {
  69       break;
  70     }
  71     if (i + len >= 1900) {
  72       break;
  73     }
  74
  75     uint8_t *frame = (got+i+9);
  76
  77     // Break and stick with current result if buffer was not completely full
  78     if (frame[0] == 0x44 && frame[1] == 0x44 && frame[3] == 0x44) { break; }
  79
  80     char line[1000] = "";
  81     int j;
  82     for (j = 0; j < len; j++) {
  83       int oddparity = 0x01;
  84       int k;
  85
  86       for (k=0;k<8;k++) {
  87         oddparity ^= (((frame[j] & 0xFF) >> k) & 0x01);
  88       }
  89
  90       //if((parityBits >> (len - j - 1)) & 0x01) {
  91       if (isResponse && (oddparity != ((parityBits >> (len - j - 1)) & 0x01))) {
  92         sprintf(line+(j*4), "%02x!  ", frame[j]);
  93       }
  94       else {
  95         sprintf(line+(j*4), "%02x   ", frame[j]);
  96       }
  97     }
  98
  99     char *crc;
 100     crc = "";
 101     if (len > 2) {
 102       uint8_t b1, b2;
 103       for (j = 0; j < (len - 1); j++) {
 104         // gives problems... search for the reason..
 105         /*if(frame[j] == 0xAA) {
 106           switch(frame[j+1]) {
 107             case 0x01:
 108               crc = "[1] Two drops close after each other";
 109             break;
 110             case 0x02:
 111               crc = "[2] Potential SOC with a drop in second half of bitperiod";
 112               break;
 113             case 0x03:
 114               crc = "[3] Segment Z after segment X is not possible";
 115               break;
 116             case 0x04:
 117               crc = "[4] Parity bit of a fully received byte was wrong";
 118               break;
 119             default:
 120               crc = "[?] Unknown error";
 121               break;
 122           }
 123           break;
 124         }*/
 125       }
 126
 127       if (strlen(crc)==0) {
 128         ComputeCrc14443(CRC_14443_A, frame, len-2, &b1, &b2);
 129         if (b1 != frame[len-2] || b2 != frame[len-1]) {
 130           crc = (isResponse & (len < 6)) ? "" : " !crc";
 131         } else {
 132           crc = "";
 133         }
 134       }
 135     } else {
 136       crc = ""; // SHORT
 137     }
 138
 139     char metricString[100];
 140     if (isResponse) {
 141       sprintf(metricString, "%3d", metric);
 142     } else {
 143       strcpy(metricString, "   ");
 144     }
 145
 146     PrintAndLog(" +%7d: %s: %s %s %s",
 147       (prev < 0 ? 0 : (timestamp - prev)),
 148       metricString,
 149       (isResponse ? "TAG" : "   "), line, crc);
 150
 151     prev = timestamp;
 152     i += (len + 9);
 153   }
 154         return 0;
 155 }
 156
 157 void iso14a_set_timeout(uint32_t timeout) {
 158         UsbCommand c = {CMD_READER_ISO_14443a, {ISO14A_SET_TIMEOUT, 0, timeout}};
 159         SendCommand(&c);
 160 }
 161
 162 int CmdHF14AMifare(const char *Cmd)
 163 {
 164         uint32_t uid = 0;
 165         uint32_t nt = 0;
 166         uint64_t par_list = 0, ks_list = 0, r_key = 0;
 167         uint8_t isOK = 0;
 168
 169         UsbCommand c = {CMD_READER_MIFARE, {strtol(Cmd, NULL, 0), 0, 0}};
 170         SendCommand(&c);
 171
 172         //flush queue
 173         while (kbhit()) getchar();
 174         while (WaitForResponseTimeout(CMD_ACK, 500) != NULL) ;
 175
 176         // message
 177         printf("-------------------------------------------------------------------------\n");
 178         printf("Executing command. It may take up to 30 min.\n");
 179         printf("Press the key on proxmark3 device to abort proxmark3.\n");
 180         printf("Press the key on the proxmark3 device to abort both proxmark3 and client.\n");
 181         printf("-------------------------------------------------------------------------\n");
 182
 183         // wait cycle
 184         while (true) {
 185                 printf(".");
 186                 if (kbhit()) {
 187                         getchar();
 188                         printf("\naborted via keyboard!\n");
 189                         break;
 190                 }
 191
 192                 UsbCommand * resp = WaitForResponseTimeout(CMD_ACK, 2000);
 193                 if (resp != NULL) {
 194                         isOK  = resp->arg[0] & 0xff;
 195
 196                         uid = (uint32_t)bytes_to_num(resp->d.asBytes +  0, 4);
 197                         nt =  (uint32_t)bytes_to_num(resp->d.asBytes +  4, 4);
 198                         par_list = bytes_to_num(resp->d.asBytes +  8, 8);
 199                         ks_list = bytes_to_num(resp->d.asBytes +  16, 8);
 200
 201                         printf("\n\n");
 202                         PrintAndLog("isOk:%02x", isOK);
 203                         if (!isOK) PrintAndLog("Proxmark can't get statistic info. Execution aborted.\n");
 204                         break;
 205                 }
 206         }
 207         printf("\n");
 208
 209         // error
 210         if (isOK != 1) return 1;
 211
 212         // execute original function from util nonce2key
 213         if (nonce2key(uid, nt, par_list, ks_list, &r_key)) return 2;
 214         printf("-------------------------------------------------------------------------\n");
 215         PrintAndLog("Key found:%012llx \n", r_key);
 216
 217         return 0;
 218 }
 219
 220 int CmdHF14AMfWrBl(const char *Cmd)
 221 {
 222         int i, temp;
 223         uint8_t blockNo = 0;
 224         uint8_t keyType = 0;
 225         uint8_t key[6] = {0, 0, 0, 0, 0, 0};
 226         uint8_t bldata[16] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
 227
 228         const char *cmdp        = Cmd;
 229         const char *cmdpe       = Cmd;
 230
 231         if (strlen(Cmd)<3) {
 232                 PrintAndLog("Usage:  hf 14 mfwrbl    <block number> <key A/B> <key (12 hex symbols)> <block data (32 hex symbols)>");
 233                 PrintAndLog("           sample: hf 14a mfwrbl 0 A FFFFFFFFFFFF 000102030405060708090A0B0C0D0E0F");
 234                 return 0;
 235         }
 236         PrintAndLog("l: %s", Cmd);
 237
 238         // skip spaces
 239         while (*cmdp==' ' || *cmdp=='\t') cmdp++;
 240         blockNo = strtol(cmdp, NULL, 0) & 0xff;
 241
 242         // next value
 243         while (*cmdp!=' ' && *cmdp!='\t') cmdp++;
 244         while (*cmdp==' ' || *cmdp=='\t') cmdp++;
 245         if (*cmdp != 'A' && *cmdp != 'a')  {
 246                 keyType = 1;
 247         }
 248
 249         // next value
 250         while (*cmdp!=' ' && *cmdp!='\t') cmdp++;
 251         while (*cmdp==' ' || *cmdp=='\t') cmdp++;
 252
 253         // next value here:cmdpe
 254         cmdpe = cmdp;
 255         while (*cmdpe!=' ' && *cmdpe!='\t') cmdpe++;
 256         while (*cmdpe==' ' || *cmdpe=='\t') cmdpe++;
 257
 258         if ((int)cmdpe - (int)cmdp != 13) {
 259                 PrintAndLog("Length of key must be 12 hex symbols");
 260                 return 0;
 261         }
 262
 263         for(i = 0; i < 6; i++) {
 264                 sscanf((char[]){cmdp[0],cmdp[1],0},"%X",&temp);
 265                 key[i] = temp & 0xff;
 266                 cmdp++;
 267                 cmdp++;
 268         }
 269
 270         // next value
 271         while (*cmdp!=' ' && *cmdp!='\t') cmdp++;
 272         while (*cmdp==' ' || *cmdp=='\t') cmdp++;
 273
 274         if (strlen(cmdp) != 32) {
 275                 PrintAndLog("Length of block data must be 32 hex symbols");
 276                 return 0;
 277         }
 278
 279         for(i = 0; i < 16; i++) {
 280                 sscanf((char[]){cmdp[0],cmdp[1],0},"%X",&temp);
 281                 bldata[i] = temp & 0xff;
 282                 cmdp++;
 283                 cmdp++;
 284         }
 285         PrintAndLog(" block no:%02x key type:%02x key:%s", blockNo, keyType, sprint_hex(key, 6));
 286         PrintAndLog(" data: %s", sprint_hex(bldata, 16));
 287
 288   UsbCommand c = {CMD_MIFARE_WRITEBL, {blockNo, keyType, 0}};
 289         memcpy(c.d.asBytes, key, 6);
 290         memcpy(c.d.asBytes + 10, bldata, 16);
 291   SendCommand(&c);
 292         UsbCommand * resp = WaitForResponseTimeout(CMD_ACK, 1500);
 293
 294         if (resp != NULL) {
 295                 uint8_t                isOK  = resp->arg[0] & 0xff;
 296
 297                 PrintAndLog("isOk:%02x", isOK);
 298         } else {
 299                 PrintAndLog("Command execute timeout");
 300         }
 301
 302         return 0;
 303 }
 304
 305 int CmdHF14AMfRdBl(const char *Cmd)
 306 {
 307         int i, temp;
 308         uint8_t blockNo = 0;
 309         uint8_t keyType = 0;
 310         uint8_t key[6] = {0, 0, 0, 0, 0, 0};
 311
 312         const char *cmdp        = Cmd;
 313
 314
 315         if (strlen(Cmd)<3) {
 316                 PrintAndLog("Usage:  hf 14 mfrdbl    <block number> <key A/B> <key (12 hex symbols)>");
 317                 PrintAndLog("           sample: hf 14a mfrdbl 0 A FFFFFFFFFFFF ");
 318                 return 0;
 319         }
 320
 321   // skip spaces
 322         while (*cmdp==' ' || *cmdp=='\t') cmdp++;
 323         blockNo = strtol(cmdp, NULL, 0) & 0xff;
 324
 325         // next value
 326         while (*cmdp!=' ' && *cmdp!='\t') cmdp++;
 327         while (*cmdp==' ' || *cmdp=='\t') cmdp++;
 328         if (*cmdp != 'A' && *cmdp != 'a')  {
 329                 keyType = 1;
 330         }
 331
 332         // next value
 333         while (*cmdp!=' ' && *cmdp!='\t') cmdp++;
 334         while (*cmdp==' ' || *cmdp=='\t') cmdp++;
 335
 336         if (strlen(cmdp) != 12) {
 337                 PrintAndLog("Length of key must be 12 hex symbols");
 338                 return 0;
 339         }
 340
 341         for(i = 0; i < 6; i++) {
 342                 sscanf((char[]){cmdp[0],cmdp[1],0},"%X",&temp);
 343                 key[i] = temp & 0xff;
 344                 cmdp++;
 345                 cmdp++;
 346         }
 347         PrintAndLog(" block no:%02x key type:%02x key:%s ", blockNo, keyType, sprint_hex(key, 6));
 348
 349   UsbCommand c = {CMD_MIFARE_READBL, {blockNo, keyType, 0}};
 350         memcpy(c.d.asBytes, key, 6);
 351   SendCommand(&c);
 352         UsbCommand * resp = WaitForResponseTimeout(CMD_ACK, 1500);
 353
 354         if (resp != NULL) {
 355                 uint8_t                isOK  = resp->arg[0] & 0xff;
 356                 uint8_t              * data  = resp->d.asBytes;
 357
 358                 PrintAndLog("isOk:%02x data:%s", isOK, sprint_hex(data, 16));
 359         } else {
 360                 PrintAndLog("Command execute timeout");
 361         }
 362
 363   return 0;
 364 }
 365
 366 int CmdHF14AMfRdSc(const char *Cmd)
 367 {
 368         int i, temp;
 369         uint8_t sectorNo = 0;
 370         uint8_t keyType = 0;
 371         uint8_t key[6] = {0, 0, 0, 0, 0, 0};
 372
 373         const char *cmdp        = Cmd;
 374
 375
 376         if (strlen(Cmd)<3) {
 377                 PrintAndLog("Usage:  hf 14 mfrdsc    <sector number> <key A/B> <key (12 hex symbols)>");
 378                 PrintAndLog("           sample: hf 14a mfrdsc 0 A FFFFFFFFFFFF ");
 379                 return 0;
 380         }
 381
 382   // skip spaces
 383         while (*cmdp==' ' || *cmdp=='\t') cmdp++;
 384         sectorNo = strtol(cmdp, NULL, 0) & 0xff;
 385
 386         // next value
 387         while (*cmdp!=' ' && *cmdp!='\t') cmdp++;
 388         while (*cmdp==' ' || *cmdp=='\t') cmdp++;
 389         if (*cmdp != 'A' && *cmdp != 'a')  {
 390                 keyType = 1;
 391         }
 392
 393         // next value
 394         while (*cmdp!=' ' && *cmdp!='\t') cmdp++;
 395         while (*cmdp==' ' || *cmdp=='\t') cmdp++;
 396
 397         if (strlen(cmdp) != 12) {
 398                 PrintAndLog("Length of key must be 12 hex symbols");
 399                 return 0;
 400         }
 401
 402         for(i = 0; i < 6; i++) {
 403                 sscanf((char[]){cmdp[0],cmdp[1],0},"%X",&temp);
 404                 key[i] = temp & 0xff;
 405                 cmdp++;
 406                 cmdp++;
 407         }
 408         PrintAndLog(" sector no:%02x key type:%02x key:%s ", sectorNo, keyType, sprint_hex(key, 6));
 409
 410   UsbCommand c = {CMD_MIFARE_READSC, {sectorNo, keyType, 0}};
 411         memcpy(c.d.asBytes, key, 6);
 412   SendCommand(&c);
 413         UsbCommand * resp = WaitForResponseTimeout(CMD_ACK, 1500);
 414         PrintAndLog(" ");
 415
 416         if (resp != NULL) {
 417                 uint8_t                isOK  = resp->arg[0] & 0xff;
 418                 uint8_t              * data  = resp->d.asBytes;
 419
 420                 PrintAndLog("isOk:%02x", isOK);
 421                 for (i = 0; i < 2; i++) {
 422                         PrintAndLog("data:%s", sprint_hex(data + i * 16, 16));
 423                 }
 424         } else {
 425                 PrintAndLog("Command1 execute timeout");
 426         }
 427
 428                 // response2
 429         resp = WaitForResponseTimeout(CMD_ACK, 500);
 430         PrintAndLog(" ");
 431
 432         if (resp != NULL) {
 433                 uint8_t              * data  = resp->d.asBytes;
 434
 435                 for (i = 0; i < 2; i++) {
 436                         PrintAndLog("data:%s", sprint_hex(data + i * 16, 16));
 437                 }
 438         } else {
 439                 PrintAndLog("Command2 execute timeout");
 440         }
 441
 442   return 0;
 443 }
 444
 445 int CmdHF14AMfNested(const char *Cmd)
 446 {
 447         int i, temp;
 448         uint8_t sectorNo = 0;
 449         uint8_t keyType = 0;
 450         uint8_t key[6] = {0, 0, 0, 0, 0, 0};
 451
 452         const char *cmdp        = Cmd;
 453
 454
 455         if (strlen(Cmd)<3) {
 456                 PrintAndLog("Usage:  hf 14a nested    <sector number> <key A/B> <key (12 hex symbols)>");
 457                 PrintAndLog("           sample: hf 14a nested 0 A FFFFFFFFFFFF ");
 458                 return 0;
 459         }
 460
 461   // skip spaces
 462         while (*cmdp==' ' || *cmdp=='\t') cmdp++;
 463         sectorNo = strtol(cmdp, NULL, 0) & 0xff;
 464
 465         // next value
 466         while (*cmdp!=' ' && *cmdp!='\t') cmdp++;
 467         while (*cmdp==' ' || *cmdp=='\t') cmdp++;
 468         if (*cmdp != 'A' && *cmdp != 'a')  {
 469                 keyType = 1;
 470         }
 471
 472         // next value
 473         while (*cmdp!=' ' && *cmdp!='\t') cmdp++;
 474         while (*cmdp==' ' || *cmdp=='\t') cmdp++;
 475
 476         if (strlen(cmdp) != 12) {
 477                 PrintAndLog("Length of key must be 12 hex symbols");
 478                 return 0;
 479         }
 480
 481         for(i = 0; i < 6; i++) {
 482                 sscanf((char[]){cmdp[0],cmdp[1],0},"%X",&temp);
 483                 key[i] = temp & 0xff;
 484                 cmdp++;
 485                 cmdp++;
 486         }
 487         PrintAndLog(" sector no:%02x key type:%02x key:%s ", sectorNo, keyType, sprint_hex(key, 6));
 488
 489   UsbCommand c = {CMD_MIFARE_NESTED, {sectorNo, keyType, 0}};
 490         memcpy(c.d.asBytes, key, 6);
 491   SendCommand(&c);
 492         UsbCommand * resp = WaitForResponseTimeout(CMD_ACK, 1500);
 493         PrintAndLog(" ");
 494
 495         if (resp != NULL) {
 496                 uint8_t                isOK  = resp->arg[0] & 0xff;
 497                 uint8_t              * data  = resp->d.asBytes;
 498
 499                 PrintAndLog("isOk:%02x", isOK);
 500                 for (i = 0; i < 2; i++) {
 501                         PrintAndLog("data:%s", sprint_hex(data + i * 16, 16));
 502                 }
 503         } else {
 504                 PrintAndLog("Command execute timeout");
 505         }
 506
 507   return 0;
 508 }
 509
 510 int CmdHF14AMf1kSim(const char *Cmd)
 511 {
 512         int i, temp;
 513         uint8_t uid[4] = {0, 0, 0, 0};
 514
 515         const char *cmdp        = Cmd;
 516
 517
 518         if (strlen(Cmd)<3) {
 519                 PrintAndLog("Usage:  hf 14a mfsim  <uid (8 hex symbols)>");
 520                 PrintAndLog("           sample: hf 14a mfsim 0a0a0a0a ");
 521                 return 0;
 522         }
 523
 524   // skip spaces
 525         while (*cmdp==' ' || *cmdp=='\t') cmdp++;
 526
 527         if (strlen(cmdp) != 8) {
 528                 PrintAndLog("Length of UID must be 8 hex symbols");
 529                 return 0;
 530         }
 531
 532         for(i = 0; i < 4; i++) {
 533                 sscanf((char[]){cmdp[0],cmdp[1],0},"%X",&temp);
 534                 uid[i] = temp & 0xff;
 535                 cmdp++;
 536                 cmdp++;
 537         }
 538         PrintAndLog(" uid:%s ", sprint_hex(uid, 4));
 539
 540   UsbCommand c = {CMD_SIMULATE_MIFARE_CARD, {0, 0, 0}};
 541         memcpy(c.d.asBytes, uid, 6);
 542   SendCommand(&c);
 543
 544   return 0;
 545 }
 546
 547
 548 int CmdHF14AReader(const char *Cmd)
 549 {
 550         UsbCommand c = {CMD_READER_ISO_14443a, {ISO14A_CONNECT, 0, 0}};
 551         SendCommand(&c);
 552         UsbCommand * resp = WaitForResponse(CMD_ACK);
 553         uint8_t              * uid  = resp->d.asBytes;
 554         iso14a_card_select_t * card = uid + 12;
 555
 556         if(resp->arg[0] == 0) {
 557                 PrintAndLog("iso14443a card select failed");
 558                 return 0;
 559         }
 560
 561         PrintAndLog("ATQA : %02x %02x", card->atqa[0], card->atqa[1]);
 562         PrintAndLog(" UID : %s", sprint_hex(uid, 12));
 563         PrintAndLog(" SAK : %02x [%d]", card->sak, resp->arg[0]);
 564         if(resp->arg[0] == 1)
 565                 PrintAndLog(" ATS : %s", sprint_hex(card->ats, card->ats_len));
 566         else
 567                 PrintAndLog("proprietary non-iso14443a card found, RATS not supported");
 568
 569         return resp->arg[0];
 570 }
 571
 572 // ## simulate iso14443a tag
 573 // ## greg - added ability to specify tag UID
 574 int CmdHF14ASim(const char *Cmd)
 575 {
 576
 577   unsigned int hi = 0, lo = 0;
 578   int n = 0, i = 0;
 579   while (sscanf(&Cmd[i++], "%1x", &n ) == 1) {
 580     hi= (hi << 4) | (lo >> 28);
 581     lo= (lo << 4) | (n & 0xf);
 582   }
 583
 584   // c.arg should be set to *Cmd or convert *Cmd to the correct format for a uid
 585   UsbCommand c = {CMD_SIMULATE_TAG_ISO_14443a, {hi, lo, 0}};
 586   PrintAndLog("Emulating 14443A TAG with UID %x%16x", hi, lo);
 587   SendCommand(&c);
 588   return 0;
 589 }
 590
 591 int CmdHF14ASnoop(const char *Cmd)
 592 {
 593   UsbCommand c = {CMD_SNOOP_ISO_14443a};
 594   SendCommand(&c);
 595   return 0;
 596 }
 597
 598 static command_t CommandTable[] =
 599 {
 600   {"help",   CmdHelp,          1, "This help"},
 601   {"list",   CmdHF14AList,     0, "List ISO 14443a history"},
 602   {"mifare", CmdHF14AMifare,   0, "Read out sector 0 parity error messages. param - <used card nonce>"},
 603   {"mfrdbl", CmdHF14AMfRdBl,   0, "Read MIFARE classic block"},
 604   {"mfrdsc", CmdHF14AMfRdSc,   0, "Read MIFARE classic sector"},
 605   {"mfwrbl", CmdHF14AMfWrBl,   0, "Write MIFARE classic block"},
 606   {"nested", CmdHF14AMfNested, 0, "Test nested authentication"},
 607   {"mfsim",  CmdHF14AMf1kSim,  0, "Simulate MIFARE 1k card - NOT WORKING!!!"},
 608   {"reader", CmdHF14AReader,   0, "Act like an ISO14443 Type A reader"},
 609   {"sim",    CmdHF14ASim,      0, "<UID> -- Fake ISO 14443a tag"},
 610   {"snoop",  CmdHF14ASnoop,    0, "Eavesdrop ISO 14443 Type A"},
 611   {NULL, NULL, 0, NULL}
 612 };
 613
 614 int CmdHF14A(const char *Cmd)
 615 {
 616   CmdsParse(CommandTable, Cmd);
 617   return 0;
 618 }
 619
 620 int CmdHelp(const char *Cmd)
 621 {
 622   CmdsHelp(CommandTable);
 623   return 0;
 624 }