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

   1 //-----------------------------------------------------------------------------
   2 // Copyright (C) 2015 Piwi
   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 // High frequency Topaz (NFC Type 1) commands
   9 //-----------------------------------------------------------------------------
  10
  11 #include "cmdhftopaz.h"
  12
  13 #include <stdio.h>
  14 #include <stdlib.h>
  15 #include <string.h>
  16 #include <unistd.h>
  17 #include "cmdmain.h"
  18 #include "cmdparser.h"
  19 #include "cmdhf14a.h"
  20 #include "ui.h"
  21 #include "mifare.h"
  22 #include "comms.h"
  23 #include "iso14443crc.h"
  24 #include "protocols.h"
  25
  26 #define TOPAZ_STATIC_MEMORY     (0x0f * 8)              // 15 blocks with 8 Bytes each
  27
  28 // a struct to describe a memory area which contains lock bits and the corresponding lockable memory area
  29 typedef struct dynamic_lock_area {
  30         struct dynamic_lock_area *next;
  31         uint16_t        byte_offset;                    // the address of the lock bits
  32         uint16_t        size_in_bits;
  33         uint16_t        first_locked_byte;              // the address of the lockable area
  34         uint16_t        bytes_locked_per_bit;
  35 } dynamic_lock_area_t;
  36
  37
  38 static struct {
  39         uint8_t HR01[2];
  40         uint8_t uid[7];
  41         uint16_t size;
  42         uint8_t data_blocks[TOPAZ_STATIC_MEMORY/8][8];  // this memory is always there
  43         uint8_t *dynamic_memory;                                                // this memory can be there
  44         dynamic_lock_area_t *dynamic_lock_areas;                // lock area descriptors
  45 } topaz_tag;
  46
  47
  48 static void topaz_switch_on_field(void)
  49 {
  50         UsbCommand c = {CMD_READER_ISO_14443a, {ISO14A_CONNECT | ISO14A_NO_SELECT | ISO14A_NO_DISCONNECT | ISO14A_TOPAZMODE, 0, 0}};
  51         SendCommand(&c);
  52 }
  53
  54
  55 static void topaz_switch_off_field(void)
  56 {
  57         UsbCommand c = {CMD_READER_ISO_14443a, {0, 0, 0}};
  58         SendCommand(&c);
  59 }
  60
  61
  62 // send a raw topaz command, returns the length of the response (0 in case of error)
  63 static int topaz_send_cmd_raw(uint8_t *cmd, uint8_t len, uint8_t *response)
  64 {
  65         UsbCommand c = {CMD_READER_ISO_14443a, {ISO14A_RAW | ISO14A_NO_DISCONNECT | ISO14A_TOPAZMODE, len, 0}};
  66         memcpy(c.d.asBytes, cmd, len);
  67         SendCommand(&c);
  68
  69         UsbCommand resp;
  70         WaitForResponse(CMD_ACK, &resp);
  71
  72         if (resp.arg[0] > 0) {
  73                 memcpy(response, resp.d.asBytes, resp.arg[0]);
  74         }
  75
  76         return resp.arg[0];
  77 }
  78
  79
  80 // calculate CRC bytes and send topaz command, returns the length of the response (0 in case of error)
  81 static int topaz_send_cmd(uint8_t *cmd, uint8_t len, uint8_t *response)
  82 {
  83         if (len > 1) {
  84         uint8_t first, second;
  85                 ComputeCrc14443(CRC_14443_B, cmd, len-2, &first, &second);
  86         cmd[len-2] = first;
  87         cmd[len-1] = second;
  88         }
  89
  90         return topaz_send_cmd_raw(cmd, len, response);
  91 }
  92
  93
  94 // select a topaz tag. Send WUPA and RID.
  95 static int topaz_select(uint8_t *atqa, uint8_t *rid_response)
  96 {
  97         // ToDo: implement anticollision
  98
  99         uint8_t wupa_cmd[] = {TOPAZ_WUPA};
 100         uint8_t rid_cmd[] = {TOPAZ_RID, 0, 0, 0, 0, 0, 0, 0, 0};
 101
 102         topaz_switch_on_field();
 103
 104         if (!topaz_send_cmd(wupa_cmd, sizeof(wupa_cmd), atqa)) {
 105                 topaz_switch_off_field();
 106                 return -1;              // WUPA failed
 107         }
 108
 109         if (!topaz_send_cmd(rid_cmd, sizeof(rid_cmd), rid_response)) {
 110                 topaz_switch_off_field();
 111                 return -2;              // RID failed
 112         }
 113
 114         return 0;               // OK
 115 }
 116
 117
 118 // read all of the static memory of a selected Topaz tag.
 119 static int topaz_rall(uint8_t *uid, uint8_t *response)
 120 {
 121         uint8_t rall_cmd[] = {TOPAZ_RALL, 0, 0, 0, 0, 0, 0, 0, 0};
 122
 123         memcpy(&rall_cmd[3], uid, 4);
 124         if (!topaz_send_cmd(rall_cmd, sizeof(rall_cmd), response)) {
 125                 topaz_switch_off_field();
 126                 return -1;              // RALL failed
 127         }
 128
 129         return 0;
 130 }
 131
 132
 133 // read a block (8 Bytes) of a selected Topaz tag.
 134 static int topaz_read_block(uint8_t *uid, uint8_t blockno, uint8_t *block_data)
 135 {
 136         uint8_t read8_cmd[] = {TOPAZ_READ8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
 137         uint8_t read8_response[11];
 138
 139         read8_cmd[1] = blockno;
 140         memcpy(&read8_cmd[10], uid, 4);
 141         if (!topaz_send_cmd(read8_cmd, sizeof(read8_cmd), read8_response)) {
 142                 topaz_switch_off_field();
 143                 return -1;              // READ8 failed
 144         }
 145
 146         memcpy(block_data, &read8_response[1], 8);
 147
 148         return 0;
 149 }
 150
 151
 152 // read a segment (16 blocks = 128 Bytes) of a selected Topaz tag. Works only for tags with dynamic memory.
 153 static int topaz_read_segment(uint8_t *uid, uint8_t segno, uint8_t *segment_data)
 154 {
 155         uint8_t rseg_cmd[] = {TOPAZ_RSEG, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
 156         uint8_t rseg_response[131];
 157
 158         rseg_cmd[1] = segno << 4;
 159         memcpy(&rseg_cmd[10], uid, 4);
 160         if (!topaz_send_cmd(rseg_cmd, sizeof(rseg_cmd), rseg_response)) {
 161                 topaz_switch_off_field();
 162                 return -1;              // RSEG failed
 163         }
 164
 165         memcpy(segment_data, &rseg_response[1], 128);
 166
 167         return 0;
 168 }
 169
 170
 171 // search for the lock area descriptor for the lockable area including byteno
 172 static dynamic_lock_area_t *get_dynamic_lock_area(uint16_t byteno)
 173 {
 174         dynamic_lock_area_t *lock_area;
 175
 176         lock_area = topaz_tag.dynamic_lock_areas;
 177
 178         while (lock_area != NULL) {
 179                 if (byteno < lock_area->first_locked_byte) {
 180                         lock_area = lock_area->next;
 181                 } else {
 182                         return lock_area;
 183                 }
 184         }
 185
 186         return NULL;
 187 }
 188
 189
 190 // check if a memory byte is locked.
 191 static bool topaz_byte_is_locked(uint16_t byteno)
 192 {
 193         uint8_t *lockbits;
 194         uint16_t locked_bytes_per_bit;
 195         dynamic_lock_area_t *lock_area;
 196
 197         if (byteno < TOPAZ_STATIC_MEMORY) {
 198                 lockbits = &topaz_tag.data_blocks[0x0e][0];
 199                 locked_bytes_per_bit = 8;
 200         } else {
 201                 lock_area = get_dynamic_lock_area(byteno);
 202                 if (lock_area == NULL) {
 203                         return false;
 204                 } else {
 205                         lockbits = &topaz_tag.dynamic_memory[lock_area->byte_offset - TOPAZ_STATIC_MEMORY];
 206                         locked_bytes_per_bit = lock_area->bytes_locked_per_bit;
 207                         byteno = byteno - lock_area->first_locked_byte;
 208                 }
 209         }
 210
 211         uint16_t blockno = byteno / locked_bytes_per_bit;
 212         if(lockbits[blockno/8] & (0x01 << (blockno % 8))) {
 213                 return true;
 214         } else {
 215                 return false;
 216         }
 217 }
 218
 219
 220 // read and print the Capability Container
 221 static int topaz_print_CC(uint8_t *data)
 222 {
 223         if(data[0] != 0xe1) {
 224                 topaz_tag.size = TOPAZ_STATIC_MEMORY;
 225                 return -1;              // no NDEF message
 226         }
 227
 228         PrintAndLog("Capability Container: %02x %02x %02x %02x", data[0], data[1], data[2], data[3]);
 229         PrintAndLog("  %02x: NDEF Magic Number", data[0]);
 230         PrintAndLog("  %02x: version %d.%d supported by tag", data[1], (data[1] & 0xF0) >> 4, data[1] & 0x0f);
 231         uint16_t memsize = (data[2] + 1) * 8;
 232         topaz_tag.size = memsize;
 233         topaz_tag.dynamic_memory = malloc(memsize - TOPAZ_STATIC_MEMORY);
 234         PrintAndLog("  %02x: Physical Memory Size of this tag: %d bytes", data[2], memsize);
 235         PrintAndLog("  %02x: %s / %s", data[3],
 236                                 (data[3] & 0xF0) ? "(RFU)" : "Read access granted without any security",
 237                                 (data[3] & 0x0F)==0 ? "Write access granted without any security" : (data[3] & 0x0F)==0x0F ? "No write access granted at all" : "(RFU)");
 238         return 0;
 239 }
 240
 241
 242 // return type, length and value of a TLV, starting at memory position *TLV_ptr
 243 static void get_TLV(uint8_t **TLV_ptr, uint8_t *TLV_type, uint16_t *TLV_length, uint8_t **TLV_value)
 244 {
 245         *TLV_length = 0;
 246         *TLV_value = NULL;
 247
 248         *TLV_type = **TLV_ptr;
 249         *TLV_ptr += 1;
 250         switch (*TLV_type) {
 251                 case 0x00:                      // NULL TLV.
 252                 case 0xFE:                      // Terminator TLV.
 253                         break;
 254                 case 0x01:                      // Lock Control TLV
 255                 case 0x02:                      // Reserved Memory TLV
 256                 case 0x03:                      // NDEF message TLV
 257                 case 0xFD:                      // proprietary TLV
 258                         *TLV_length = **TLV_ptr;
 259                         *TLV_ptr += 1;
 260                         if (*TLV_length == 0xff) {
 261                                 *TLV_length = **TLV_ptr << 8;
 262                                 *TLV_ptr += 1;
 263                                 *TLV_length |= **TLV_ptr;
 264                                 *TLV_ptr += 1;
 265                         }
 266                         *TLV_value = *TLV_ptr;
 267                         *TLV_ptr += *TLV_length;
 268                         break;
 269                 default:                        // RFU
 270                         break;
 271         }
 272 }
 273
 274
 275 // lock area TLVs contain no information on the start of the respective lockable area. Lockable areas
 276 // do not include the lock bits and reserved memory. We therefore need to adjust the start of the
 277 // respective lockable areas accordingly
 278 static void adjust_lock_areas(uint16_t block_start, uint16_t block_size)
 279 {
 280         dynamic_lock_area_t *lock_area = topaz_tag.dynamic_lock_areas;
 281         while (lock_area != NULL) {
 282                 if (lock_area->first_locked_byte <= block_start) {
 283                         lock_area->first_locked_byte += block_size;
 284                 }
 285                 lock_area = lock_area->next;
 286         }
 287 }
 288
 289
 290 // read and print the lock area and reserved memory TLVs
 291 static void topaz_print_control_TLVs(uint8_t *memory)
 292 {
 293         uint8_t *TLV_ptr = memory;
 294         uint8_t TLV_type = 0;
 295         uint16_t TLV_length;
 296         uint8_t *TLV_value;
 297         bool lock_TLV_present = false;
 298         bool reserved_memory_control_TLV_present = false;
 299         uint16_t next_lockable_byte = 0x0f * 8;                         // first byte after static memory area
 300
 301         while(*TLV_ptr != 0x03 && *TLV_ptr != 0xFD && *TLV_ptr != 0xFE) {
 302                 // all Lock Control TLVs shall be present before the NDEF message TLV, the proprietary TLV (and the Terminator TLV)
 303                 get_TLV(&TLV_ptr, &TLV_type, &TLV_length, &TLV_value);
 304                 if (TLV_type == 0x01) {                 // a Lock Control TLV
 305                         uint8_t pages_addr = TLV_value[0] >> 4;
 306                         uint8_t byte_offset = TLV_value[0] & 0x0f;
 307                         uint16_t size_in_bits = TLV_value[1] ? TLV_value[1] : 256;
 308                         uint16_t size_in_bytes = (size_in_bits + 7)/8;
 309                         uint16_t bytes_per_page = 1 << (TLV_value[2] & 0x0f);
 310                         uint16_t bytes_locked_per_bit = 1 << (TLV_value[2] >> 4);
 311                         uint16_t area_start = pages_addr * bytes_per_page + byte_offset;
 312                         PrintAndLog("Lock Area of %d bits at byte offset 0x%04x. Each Lock Bit locks %d bytes.",
 313                                                 size_in_bits,
 314                                                 area_start,
 315                                                 bytes_locked_per_bit);
 316                         lock_TLV_present = true;
 317                         dynamic_lock_area_t *old = topaz_tag.dynamic_lock_areas;
 318                         dynamic_lock_area_t *new = topaz_tag.dynamic_lock_areas;
 319                         if (old == NULL) {
 320                                 new = topaz_tag.dynamic_lock_areas = (dynamic_lock_area_t *)malloc(sizeof(dynamic_lock_area_t));
 321                         } else {
 322                                 while(old->next != NULL) {
 323                                         old = old->next;
 324                                 }
 325                                 new = old->next = (dynamic_lock_area_t *)malloc(sizeof(dynamic_lock_area_t));
 326                         }
 327                         new->next = NULL;
 328                         if (area_start <= next_lockable_byte) {
 329                                 // lock areas are not lockable
 330                                 next_lockable_byte += size_in_bytes;
 331                         }
 332                         new->first_locked_byte = next_lockable_byte;
 333                         new->byte_offset = area_start;
 334                         new->size_in_bits = size_in_bits;
 335                         new->bytes_locked_per_bit = bytes_locked_per_bit;
 336                         next_lockable_byte += size_in_bits * bytes_locked_per_bit;
 337                 }
 338                 if (TLV_type == 0x02) {                 // a Reserved Memory Control TLV
 339                         uint8_t pages_addr = TLV_value[0] >> 4;
 340                         uint8_t byte_offset = TLV_value[0] & 0x0f;
 341                         uint16_t size_in_bytes = TLV_value[1] ? TLV_value[1] : 256;
 342                         uint8_t bytes_per_page = 1 << (TLV_value[2] & 0x0f);
 343                         uint16_t area_start = pages_addr * bytes_per_page + byte_offset;
 344                         PrintAndLog("Reserved Memory of %d bytes at byte offset 0x%02x.",
 345                                                 size_in_bytes,
 346                                                 area_start);
 347                         reserved_memory_control_TLV_present = true;
 348                         adjust_lock_areas(area_start, size_in_bytes);  // reserved memory areas are not lockable
 349                         if (area_start <= next_lockable_byte) {
 350                                 next_lockable_byte += size_in_bytes;
 351                         }
 352                 }
 353         }
 354
 355         if (!lock_TLV_present) {
 356                 PrintAndLog("(No Lock Control TLV present)");
 357         }
 358
 359         if (!reserved_memory_control_TLV_present) {
 360                 PrintAndLog("(No Reserved Memory Control TLV present)");
 361         }
 362 }
 363
 364
 365 // read all of the dynamic memory
 366 static int topaz_read_dynamic_data(void)
 367 {
 368         // first read the remaining block of segment 0
 369         if(topaz_read_block(topaz_tag.uid, 0x0f, &topaz_tag.dynamic_memory[0]) == -1) {
 370                 PrintAndLog("Error while reading dynamic memory block %02x. Aborting...", 0x0f);
 371                 return -1;
 372         }
 373
 374         // read the remaining segments
 375         uint8_t max_segment = topaz_tag.size / 128 - 1;
 376         for(uint8_t segment = 1; segment <= max_segment; segment++) {
 377                 if(topaz_read_segment(topaz_tag.uid, segment, &topaz_tag.dynamic_memory[(segment-1)*128+8]) == -1) {
 378                         PrintAndLog("Error while reading dynamic memory block %02x. Aborting...", 0x0f);
 379                         return -1;
 380                 }
 381         }
 382
 383         return 0;
 384 }
 385
 386
 387 // read and print the dynamic memory
 388 static void topaz_print_dynamic_data(void)
 389 {
 390         if (topaz_tag.size > TOPAZ_STATIC_MEMORY) {
 391                 PrintAndLog("Dynamic Data blocks:");
 392                 if (topaz_read_dynamic_data() == 0) {
 393                         PrintAndLog("block# | offset | Data                    | Locked(y/n)");
 394                         char line[80];
 395                         for (uint16_t blockno = 0x0f; blockno < topaz_tag.size/8; blockno++) {
 396                                 uint8_t *block_data = &topaz_tag.dynamic_memory[(blockno-0x0f)*8];
 397                                 char lockbits[9];
 398                                 for (uint16_t j = 0; j < 8; j++) {
 399                                         sprintf(&line[3*j], "%02x ", block_data[j]);
 400                                         lockbits[j] = topaz_byte_is_locked(blockno*8+j) ? 'y' : 'n';
 401                                 }
 402                                 lockbits[8] = '\0';
 403                                 PrintAndLog("  0x%02x | 0x%04x | %s|   %-3s", blockno, blockno*8, line, lockbits);
 404                         }
 405                 }
 406         }
 407 }
 408
 409
 410 static void topaz_print_lifecycle_state(uint8_t *data)
 411 {
 412         // to be done
 413 }
 414
 415
 416 static void topaz_print_NDEF(uint8_t *data)
 417 {
 418         // to be done.
 419 }
 420
 421
 422 // read a Topaz tag and print some usefull information
 423 int CmdHFTopazReader(const char *Cmd)
 424 {
 425         int status;
 426         uint8_t atqa[2];
 427         uint8_t rid_response[8];
 428         uint8_t *uid_echo = &rid_response[2];
 429         uint8_t rall_response[124];
 430
 431         status = topaz_select(atqa, rid_response);
 432
 433         if (status == -1) {
 434                 PrintAndLog("Error: couldn't receive ATQA");
 435                 return -1;
 436         }
 437
 438         PrintAndLog("ATQA : %02x %02x", atqa[1], atqa[0]);
 439         if (atqa[1] != 0x0c && atqa[0] != 0x00) {
 440                 PrintAndLog("Tag doesn't support the Topaz protocol.");
 441                 topaz_switch_off_field();
 442                 return -1;
 443         }
 444
 445         if (status == -2) {
 446                 PrintAndLog("Error: tag didn't answer to RID");
 447                 topaz_switch_off_field();
 448                 return -1;
 449         }
 450
 451         topaz_tag.HR01[0] = rid_response[0];
 452         topaz_tag.HR01[1] = rid_response[1];
 453
 454         // ToDo: CRC check
 455         PrintAndLog("HR0  : %02x (%sa Topaz tag (%scapable of carrying a NDEF message), %s memory map)", rid_response[0],
 456                                                 (rid_response[0] & 0xF0) == 0x10 ? "" : "not ",
 457                                                 (rid_response[0] & 0xF0) == 0x10 ? "" : "not ",
 458                                                 (rid_response[0] & 0x0F) == 0x01 ? "static" : "dynamic");
 459         PrintAndLog("HR1  : %02x", rid_response[1]);
 460
 461         status = topaz_rall(uid_echo, rall_response);
 462
 463         if(status == -1) {
 464                 PrintAndLog("Error: tag didn't answer to RALL");
 465                 topaz_switch_off_field();
 466                 return -1;
 467         }
 468
 469         memcpy(topaz_tag.uid, rall_response+2, 7);
 470         PrintAndLog("UID  : %02x %02x %02x %02x %02x %02x %02x",
 471                         topaz_tag.uid[6],
 472                         topaz_tag.uid[5],
 473                         topaz_tag.uid[4],
 474                         topaz_tag.uid[3],
 475                         topaz_tag.uid[2],
 476                         topaz_tag.uid[1],
 477                         topaz_tag.uid[0]);
 478         PrintAndLog("       UID[6] (Manufacturer Byte) = %02x, Manufacturer: %s",
 479                         topaz_tag.uid[6],
 480                         getTagInfo(topaz_tag.uid[6]));
 481
 482         memcpy(topaz_tag.data_blocks, rall_response+2, 0x0f*8);
 483         PrintAndLog("");
 484         PrintAndLog("Static Data blocks 00 to 0c:");
 485         PrintAndLog("block# | offset | Data                    | Locked(y/n)");
 486         char line[80];
 487         for (uint16_t i = 0; i <= 0x0c; i++) {
 488                 char lockbits[9];
 489                 for (uint16_t j = 0; j < 8; j++) {
 490                         sprintf(&line[3*j], "%02x ", topaz_tag.data_blocks[i][j] /*rall_response[2 + 8*i + j]*/);
 491                         lockbits[j] = topaz_byte_is_locked(i*8+j) ? 'y' : 'n';
 492                 }
 493                 lockbits[8] = '\0';
 494                 PrintAndLog("  0x%02x | 0x%04x | %s|   %-3s", i, i*8, line, lockbits);
 495         }
 496
 497         PrintAndLog("");
 498         PrintAndLog("Static Reserved block 0d:");
 499         for (uint16_t j = 0; j < 8; j++) {
 500                 sprintf(&line[3*j], "%02x ", topaz_tag.data_blocks[0x0d][j]);
 501         }
 502         PrintAndLog("  0x%02x | 0x%04x | %s|   %-3s", 0x0d, 0x0d*8, line, "n/a");
 503
 504         PrintAndLog("");
 505         PrintAndLog("Static Lockbits and OTP Bytes:");
 506         for (uint16_t j = 0; j < 8; j++) {
 507                 sprintf(&line[3*j], "%02x ", topaz_tag.data_blocks[0x0e][j]);
 508         }
 509         PrintAndLog("  0x%02x | 0x%04x | %s|   %-3s", 0x0e, 0x0e*8, line, "n/a");
 510
 511         PrintAndLog("");
 512
 513         status = topaz_print_CC(&topaz_tag.data_blocks[1][0]);
 514
 515         if (status == -1) {
 516                 PrintAndLog("No NDEF message data present");
 517                 topaz_switch_off_field();
 518                 return 0;
 519         }
 520
 521         PrintAndLog("");
 522         topaz_print_control_TLVs(&topaz_tag.data_blocks[1][4]);
 523
 524         PrintAndLog("");
 525         topaz_print_dynamic_data();
 526
 527         topaz_print_lifecycle_state(&topaz_tag.data_blocks[1][0]);
 528
 529         topaz_print_NDEF(&topaz_tag.data_blocks[1][0]);
 530
 531         topaz_switch_off_field();
 532         return 0;
 533 }
 534
 535
 536 int CmdHFTopazCmdRaw(const char *Cmd)
 537 {
 538         PrintAndLog("not yet implemented. Use hf 14 raw with option -T.");
 539         return 0;
 540 }
 541
 542
 543 static int CmdHelp(const char *Cmd);
 544
 545
 546 static command_t CommandTable[] =
 547 {
 548         {"help",        CmdHelp,                        1, "This help"},
 549         {"reader",      CmdHFTopazReader,       0, "Act like a Topaz reader"},
 550         {"snoop",       CmdHF14ASnoop,          0, "Eavesdrop a Topaz reader-tag communication"},
 551         {"raw",         CmdHFTopazCmdRaw,       0, "Send raw hex data to tag"},
 552         {NULL,          NULL,                           0, NULL}
 553 };
 554
 555
 556 int CmdHFTopaz(const char *Cmd) {
 557         (void)WaitForResponseTimeout(CMD_ACK,NULL,100);
 558         CmdsParse(CommandTable, Cmd);
 559         return 0;
 560 }
 561
 562
 563 static int CmdHelp(const char *Cmd)
 564 {
 565         CmdsHelp(CommandTable);
 566         return 0;
 567 }
 568
 569