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   1 /***************************************************************************
   2  *   Copyright (C) 2005 by Dominic Rath                                    *
   3  *   Dominic.Rath@gmx.de                                                   *
   4  *                                                                         *
   5  *   Copyright (C) 2007,2008 Øyvind Harboe                                      *
   6  *   oyvind.harboe@zylin.com                                               *
   7  *                                                                         *
   8  *   This program is free software; you can redistribute it and/or modify  *
   9  *   it under the terms of the GNU General Public License as published by  *
  10  *   the Free Software Foundation; either version 2 of the License, or     *
  11  *   (at your option) any later version.                                   *
  12  *                                                                         *
  13  *   This program is distributed in the hope that it will be useful,       *
  14  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  15  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
  16  *   GNU General Public License for more details.                          *
  17  *                                                                         *
  18  *   You should have received a copy of the GNU General Public License     *
  19  *   along with this program; if not, write to the                         *
  20  *   Free Software Foundation, Inc.,                                       *
  21  *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
  22  ***************************************************************************/
  23 #ifdef HAVE_CONFIG_H
  24 #include "config.h"
  25 #endif
  26
  27 #include "replacements.h"
  28
  29 #include "telnet_server.h"
  30
  31 #include "server.h"
  32 #include "log.h"
  33 #include "command.h"
  34 #include "target.h"
  35 #include "target_request.h"
  36
  37 #include <stdlib.h>
  38 #include <unistd.h>
  39 #include <errno.h>
  40 #include <string.h>
  41 #include <ctype.h>
  42
  43 static unsigned short telnet_port = 0;
  44
  45 int handle_exit_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc);
  46 int handle_telnet_port_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc);
  47
  48 static char *negotiate =
  49                 "\xFF\xFB\x03"          /* IAC WILL Suppress Go Ahead */
  50                 "\xFF\xFB\x01"          /* IAC WILL Echo */
  51                 "\xFF\xFD\x03"          /* IAC DO Suppress Go Ahead */
  52                 "\xFF\xFE\x01";         /* IAC DON'T Echo */
  53
  54 #define CTRL(c) (c - '@')
  55
  56 /* The only way we can detect that the socket is closed is the first time
  57  * we write to it, we will fail. Subsequent write operations will
  58  * succeed. Shudder!
  59  */
  60 int telnet_write(connection_t *connection, const void *data, int len)
  61 {
  62         telnet_connection_t *t_con = connection->priv;
  63         if (t_con->closed)
  64                 return ERROR_SERVER_REMOTE_CLOSED;
  65
  66         if (write_socket(connection->fd, data, len) == len)
  67         {
  68                 return ERROR_OK;
  69         }
  70         t_con->closed = 1;
  71         return ERROR_SERVER_REMOTE_CLOSED;
  72 }
  73
  74 int telnet_prompt(connection_t *connection)
  75 {
  76         telnet_connection_t *t_con = connection->priv;
  77
  78         telnet_write(connection, "\r", 1); /* the prompt is always placed at the line beginning */
  79         return telnet_write(connection, t_con->prompt, strlen(t_con->prompt));
  80 }
  81
  82 int telnet_outputline(connection_t *connection, const char *line)
  83 {
  84         int len;
  85
  86         /* process lines in buffer */
  87         while (*line) {
  88                 char *line_end = strchr(line, '\n');
  89
  90                 if (line_end)
  91                         len = line_end-line;
  92                 else
  93                         len = strlen(line);
  94
  95                 telnet_write(connection, line, len);
  96                 if (line_end)
  97                 {
  98                         telnet_write(connection, "\r\n", 2);
  99                         line += len+1;
 100                 }
 101                 else
 102                 {
 103                         line += len;
 104                 }
 105         }
 106
 107         return ERROR_OK;
 108 }
 109
 110 int telnet_output(struct command_context_s *cmd_ctx, const char* line)
 111 {
 112         connection_t *connection = cmd_ctx->output_handler_priv;
 113
 114         return telnet_outputline(connection, line);
 115 }
 116
 117 void telnet_log_callback(void *priv, const char *file, int line,
 118                 const char *function, const char *string)
 119 {
 120         connection_t *connection = priv;
 121         telnet_connection_t *t_con = connection->priv;
 122         int i;
 123
 124         /* if there is no prompt, simply output the message */
 125         if (t_con->line_cursor < 0)
 126         {
 127                 telnet_outputline(connection, string);
 128                 return;
 129         }
 130
 131         /* clear the command line */
 132         telnet_write(connection, "\r", 1);
 133         for (i = strlen(t_con->prompt) + t_con->line_size; i>0; i-=16)
 134                 telnet_write(connection, "                ", i>16 ? 16 : i);
 135         telnet_write(connection, "\r", 1);
 136
 137         /* output the message */
 138         telnet_outputline(connection, string);
 139
 140         /* put the command line to its previous state */
 141         telnet_prompt(connection);
 142         telnet_write(connection, t_con->line, t_con->line_size);
 143         for (i=t_con->line_size; i>t_con->line_cursor; i--)
 144                 telnet_write(connection, "\b", 1);
 145 }
 146
 147 int telnet_new_connection(connection_t *connection)
 148 {
 149         telnet_connection_t *telnet_connection = malloc(sizeof(telnet_connection_t));
 150         telnet_service_t *telnet_service = connection->service->priv;
 151         int i;
 152
 153         connection->priv = telnet_connection;
 154
 155         /* initialize telnet connection information */
 156         telnet_connection->closed = 0;
 157         telnet_connection->line_size = 0;
 158         telnet_connection->line_cursor = 0;
 159         telnet_connection->option_size = 0;
 160         telnet_connection->prompt = strdup("> ");
 161         telnet_connection->state = TELNET_STATE_DATA;
 162
 163         /* output goes through telnet connection */
 164         command_set_output_handler(connection->cmd_ctx, telnet_output, connection);
 165
 166         /* negotiate telnet options */
 167         telnet_write(connection, negotiate, strlen(negotiate));
 168
 169         /* print connection banner */
 170         if (telnet_service->banner)
 171         {
 172                 telnet_write(connection, telnet_service->banner, strlen(telnet_service->banner));
 173                 telnet_write(connection, "\r\n", 2);
 174         }
 175
 176         telnet_prompt(connection);
 177
 178         /* initialize history */
 179         for (i = 0; i < TELNET_LINE_HISTORY_SIZE; i++)
 180         {
 181                 telnet_connection->history[i] = NULL;
 182         }
 183         telnet_connection->next_history = 0;
 184         telnet_connection->current_history = 0;
 185
 186         log_add_callback(telnet_log_callback, connection);
 187
 188
 189
 190         return ERROR_OK;
 191 }
 192
 193 void telnet_clear_line(connection_t *connection, telnet_connection_t *t_con)
 194 {
 195         /* move to end of line */
 196         if (t_con->line_cursor < t_con->line_size)
 197         {
 198                 telnet_write(connection, t_con->line + t_con->line_cursor, t_con->line_size - t_con->line_cursor);
 199         }
 200
 201         /* backspace, overwrite with space, backspace */
 202         while (t_con->line_size > 0)
 203         {
 204                 telnet_write(connection, "\b \b", 3);
 205                 t_con->line_size--;
 206         }
 207         t_con->line_cursor = 0;
 208 }
 209
 210 int telnet_input(connection_t *connection)
 211 {
 212         int bytes_read;
 213         char buffer[TELNET_BUFFER_SIZE];
 214         char *buf_p;
 215         telnet_connection_t *t_con = connection->priv;
 216         command_context_t *command_context = connection->cmd_ctx;
 217
 218         bytes_read = read_socket(connection->fd, buffer, TELNET_BUFFER_SIZE);
 219
 220         if (bytes_read == 0)
 221                 return ERROR_SERVER_REMOTE_CLOSED;
 222         else if (bytes_read == -1)
 223         {
 224                 LOG_ERROR("error during read: %s", strerror(errno));
 225                 return ERROR_SERVER_REMOTE_CLOSED;
 226         }
 227
 228         buf_p = buffer;
 229         while (bytes_read)
 230         {
 231                 switch (t_con->state)
 232                 {
 233                         case TELNET_STATE_DATA:
 234                                 if (*buf_p == '\xff')
 235                                 {
 236                                         t_con->state = TELNET_STATE_IAC;
 237                                 }
 238                                 else
 239                                 {
 240                                         if (isprint(*buf_p)) /* printable character */
 241                                         {
 242                                                 /* watch buffer size leaving one spare character for string null termination */
 243                                                 if (t_con->line_size == TELNET_LINE_MAX_SIZE-1)
 244                                                 {
 245                                                         /* output audible bell if buffer is full */
 246                                                         telnet_write(connection, "\x07", 1); /* "\a" does not work, at least on windows */
 247                                                 }
 248                                                 else if (t_con->line_cursor == t_con->line_size)
 249                                                 {
 250                                                         telnet_write(connection, buf_p, 1);
 251                                                         t_con->line[t_con->line_size++] = *buf_p;
 252                                                         t_con->line_cursor++;
 253                                                 }
 254                                                 else
 255                                                 {
 256                                                         int i;
 257                                                         memmove(t_con->line + t_con->line_cursor + 1, t_con->line + t_con->line_cursor, t_con->line_size - t_con->line_cursor);
 258                                                         t_con->line[t_con->line_cursor] = *buf_p;
 259                                                         t_con->line_size++;
 260                                                         telnet_write(connection, t_con->line + t_con->line_cursor, t_con->line_size - t_con->line_cursor);
 261                                                         t_con->line_cursor++;
 262                                                         for (i = t_con->line_cursor; i < t_con->line_size; i++)
 263                                                         {
 264                                                                 telnet_write(connection, "\b", 1);
 265                                                         }
 266                                                 }
 267                                         }
 268                                         else /* non-printable */
 269                                         {
 270                                                 if (*buf_p == 0x1b) /* escape */
 271                                                 {
 272                                                         t_con->state = TELNET_STATE_ESCAPE;
 273                                                         t_con->last_escape = '\x00';
 274                                                 }
 275                                                 else if ((*buf_p == 0xd) || (*buf_p == 0xa)) /* CR/LF */
 276                                                 {
 277                                                         int retval;
 278
 279                                                         /* skip over combinations with CR/LF and NUL characters */
 280                                                         if ((bytes_read > 1) && ((*(buf_p + 1) == 0xa) || (*(buf_p + 1) == 0xd)))
 281                                                         {
 282                                                                 buf_p++;
 283                                                                 bytes_read--;
 284                                                         }
 285                                                         if ((bytes_read > 1) && (*(buf_p + 1) == 0))
 286                                                         {
 287                                                                 buf_p++;
 288                                                                 bytes_read--;
 289                                                         }
 290                                                         t_con->line[t_con->line_size] = 0;
 291
 292                                                         telnet_write(connection, "\r\n\x00", 3);
 293
 294                                                         if (strcmp(t_con->line, "history") == 0)
 295                                                         {
 296                                                                 int i;
 297                                                                 for (i = 1; i < TELNET_LINE_HISTORY_SIZE; i++)
 298                                                                 {
 299                                                                         /* the t_con->next_history line contains empty string (unless NULL), thus it is not printed */
 300                                                                         char *history_line = t_con->history[(t_con->next_history + i) % TELNET_LINE_HISTORY_SIZE];
 301                                                                         if (history_line)
 302                                                                         {
 303                                                                                 telnet_write(connection, history_line, strlen(history_line));
 304                                                                                 telnet_write(connection, "\r\n\x00", 3);
 305                                                                         }
 306                                                                 }
 307                                                                 t_con->line_size = 0;
 308                                                                 t_con->line_cursor = 0;
 309                                                                 continue;
 310                                                         }
 311
 312                                                         /* save only non-blank not repeating lines in the history */
 313                                                         char *prev_line = t_con->history[(t_con->current_history > 0) ? t_con->current_history - 1 : TELNET_LINE_HISTORY_SIZE-1];
 314                                                         if (*t_con->line && (prev_line == NULL || strcmp(t_con->line, prev_line)))
 315                                                         {
 316                                                                 /* if the history slot is already taken, free it */
 317                                                                 if (t_con->history[t_con->next_history])
 318                                                                 {
 319                                                                         free(t_con->history[t_con->next_history]);
 320                                                                 }
 321
 322                                                                 /* add line to history */
 323                                                                 t_con->history[t_con->next_history] = strdup(t_con->line);
 324
 325                                                                 /* wrap history at TELNET_LINE_HISTORY_SIZE */
 326                                                                 t_con->next_history = (t_con->next_history + 1) % TELNET_LINE_HISTORY_SIZE;
 327
 328                                                                 /* current history line starts at the new entry */
 329                                                                 t_con->current_history = t_con->next_history;
 330
 331                                                                 if (t_con->history[t_con->current_history])
 332                                                                 {
 333                                                                         free(t_con->history[t_con->current_history]);
 334                                                                 }
 335                                                                 t_con->history[t_con->current_history] = strdup("");
 336                                                         }
 337
 338                                                         t_con->line_size = 0;
 339
 340                                                         t_con->line_cursor = -1; /* to supress prompt in log callback during command execution */
 341                                                         retval = command_run_line(command_context, t_con->line);
 342                                                         t_con->line_cursor = 0;
 343
 344                                                         if (retval == ERROR_COMMAND_CLOSE_CONNECTION)
 345                                                                 return ERROR_SERVER_REMOTE_CLOSED;
 346
 347                                                         retval = telnet_prompt(connection);
 348                                                         if (retval == ERROR_SERVER_REMOTE_CLOSED)
 349                                                                 return ERROR_SERVER_REMOTE_CLOSED;
 350
 351                                                 }
 352                                                 else if ((*buf_p == 0x7f) || (*buf_p == 0x8)) /* delete character */
 353                                                 {
 354                                                         if (t_con->line_cursor > 0)
 355                                                         {
 356                                                                 if (t_con->line_cursor != t_con->line_size)
 357                                                                 {
 358                                                                         int i;
 359                                                                         telnet_write(connection, "\b", 1);
 360                                                                         t_con->line_cursor--;
 361                                                                         t_con->line_size--;
 362                                                                         memmove(t_con->line + t_con->line_cursor, t_con->line + t_con->line_cursor + 1, t_con->line_size - t_con->line_cursor);
 363
 364                                                                         telnet_write(connection, t_con->line + t_con->line_cursor, t_con->line_size - t_con->line_cursor);
 365                                                                         telnet_write(connection, " \b", 2);
 366                                                                         for (i = t_con->line_cursor; i < t_con->line_size; i++)
 367                                                                         {
 368                                                                                 telnet_write(connection, "\b", 1);
 369                                                                         }
 370                                                                 }
 371                                                                 else
 372                                                                 {
 373                                                                         t_con->line_size--;
 374                                                                         t_con->line_cursor--;
 375                                                                         /* back space: move the 'printer' head one char back, overwrite with space, move back again */
 376                                                                         telnet_write(connection, "\b \b", 3);
 377                                                                 }
 378                                                         }
 379                                                 }
 380                                                 else if (*buf_p == 0x15) /* clear line */
 381                                                 {
 382                                                         telnet_clear_line(connection, t_con);
 383                                                 }
 384                                                 else if (*buf_p == CTRL('B')) /* cursor left */
 385                                                 {
 386                                                         if (t_con->line_cursor > 0)
 387                                                         {
 388                                                                 telnet_write(connection, "\b", 1);
 389                                                                 t_con->line_cursor--;
 390                                                         }
 391                                                         t_con->state = TELNET_STATE_DATA;
 392                                                 }
 393                                                 else if (*buf_p == CTRL('F')) /* cursor right */
 394                                                 {
 395                                                         if (t_con->line_cursor < t_con->line_size)
 396                                                         {
 397                                                                 telnet_write(connection, t_con->line + t_con->line_cursor++, 1);
 398                                                         }
 399                                                         t_con->state = TELNET_STATE_DATA;
 400                                                 }
 401                                                 else
 402                                                 {
 403                                                         LOG_DEBUG("unhandled nonprintable: %2.2x", *buf_p);
 404                                                 }
 405                                         }
 406                                 }
 407                                 break;
 408                         case TELNET_STATE_IAC:
 409                                 switch (*buf_p)
 410                                 {
 411                                         case '\xfe':
 412                                                 t_con->state = TELNET_STATE_DONT;
 413                                                 break;
 414                                         case '\xfd':
 415                                                 t_con->state = TELNET_STATE_DO;
 416                                                 break;
 417                                         case '\xfc':
 418                                                 t_con->state = TELNET_STATE_WONT;
 419                                                 break;
 420                                         case '\xfb':
 421                                                 t_con->state = TELNET_STATE_WILL;
 422                                                 break;
 423                                 }
 424                                 break;
 425                         case TELNET_STATE_SB:
 426                                 break;
 427                         case TELNET_STATE_SE:
 428                                 break;
 429                         case TELNET_STATE_WILL:
 430                         case TELNET_STATE_WONT:
 431                         case TELNET_STATE_DO:
 432                         case TELNET_STATE_DONT:
 433                                 t_con->state = TELNET_STATE_DATA;
 434                                 break;
 435                         case TELNET_STATE_ESCAPE:
 436                                 if (t_con->last_escape == '[')
 437                                 {
 438                                         if (*buf_p == 'D') /* cursor left */
 439                                         {
 440                                                 if (t_con->line_cursor > 0)
 441                                                 {
 442                                                         telnet_write(connection, "\b", 1);
 443                                                         t_con->line_cursor--;
 444                                                 }
 445                                                 t_con->state = TELNET_STATE_DATA;
 446                                         }
 447                                         else if (*buf_p == 'C') /* cursor right */
 448                                         {
 449                                                 if (t_con->line_cursor < t_con->line_size)
 450                                                 {
 451                                                         telnet_write(connection, t_con->line + t_con->line_cursor++, 1);
 452                                                 }
 453                                                 t_con->state = TELNET_STATE_DATA;
 454                                         }
 455                                         else if (*buf_p == 'A') /* cursor up */
 456                                         {
 457                                                 int last_history = (t_con->current_history > 0) ? t_con->current_history - 1 : TELNET_LINE_HISTORY_SIZE-1;
 458                                                 if (t_con->history[last_history])
 459                                                 {
 460                                                         telnet_clear_line(connection, t_con);
 461                                                         t_con->line_size = strlen(t_con->history[last_history]);
 462                                                         t_con->line_cursor = t_con->line_size;
 463                                                         memcpy(t_con->line, t_con->history[last_history], t_con->line_size);
 464                                                         telnet_write(connection, t_con->line, t_con->line_size);
 465                                                         t_con->current_history = last_history;
 466                                                 }
 467                                                 t_con->state = TELNET_STATE_DATA;
 468                                         }
 469                                         else if (*buf_p == 'B') /* cursor down */
 470                                         {
 471                                                 int next_history = (t_con->current_history + 1) % TELNET_LINE_HISTORY_SIZE;
 472                                                 if (t_con->history[next_history])
 473                                                 {
 474                                                         telnet_clear_line(connection, t_con);
 475                                                         t_con->line_size = strlen(t_con->history[next_history]);
 476                                                         t_con->line_cursor = t_con->line_size;
 477                                                         memcpy(t_con->line, t_con->history[next_history], t_con->line_size);
 478                                                         telnet_write(connection, t_con->line, t_con->line_size);
 479                                                         t_con->current_history = next_history;
 480                                                 }
 481                                                 t_con->state = TELNET_STATE_DATA;
 482                                         }
 483                                         else if (*buf_p == '3')
 484                                         {
 485                                                 t_con->last_escape = *buf_p;
 486                                         }
 487                                         else
 488                                         {
 489                                                 t_con->state = TELNET_STATE_DATA;
 490                                         }
 491                                 }
 492                                 else if (t_con->last_escape == '3')
 493                                 {
 494                                         /* Remove character */
 495                                         if (*buf_p == '~')
 496                                         {
 497                                                 if (t_con->line_cursor < t_con->line_size)
 498                                                 {
 499                                                         int i;
 500                                                         t_con->line_size--;
 501                                                         /* remove char from line buffer */
 502                                                         memmove(t_con->line + t_con->line_cursor, t_con->line + t_con->line_cursor + 1, t_con->line_size - t_con->line_cursor);
 503
 504                                                         /* print remainder of buffer */
 505                                                         telnet_write(connection, t_con->line + t_con->line_cursor, t_con->line_size - t_con->line_cursor);
 506                                                         /* overwrite last char with whitespace */
 507                                                         telnet_write(connection, " \b", 2);
 508
 509                                                         /* move back to cursor position*/
 510                                                         for (i = t_con->line_cursor; i < t_con->line_size; i++)
 511                                                         {
 512                                                                 telnet_write(connection, "\b", 1);
 513                                                         }
 514                                                 }
 515
 516                                                 t_con->state = TELNET_STATE_DATA;
 517                                         }
 518                                         else
 519                                         {
 520                                                 t_con->state = TELNET_STATE_DATA;
 521                                         }
 522                                 }
 523                                 else if (t_con->last_escape == '\x00')
 524                                 {
 525                                         if (*buf_p == '[')
 526                                         {
 527                                                 t_con->last_escape = *buf_p;
 528                                         }
 529                                         else
 530                                         {
 531                                                 t_con->state = TELNET_STATE_DATA;
 532                                         }
 533                                 }
 534                                 else
 535                                 {
 536                                         LOG_ERROR("BUG: unexpected value in t_con->last_escape");
 537                                         t_con->state = TELNET_STATE_DATA;
 538                                 }
 539
 540                                 break;
 541                         default:
 542                                 LOG_ERROR("unknown telnet state");
 543                                 exit(-1);
 544                 }
 545
 546                 bytes_read--;
 547                 buf_p++;
 548         }
 549
 550         return ERROR_OK;
 551 }
 552
 553 int telnet_connection_closed(connection_t *connection)
 554 {
 555         telnet_connection_t *t_con = connection->priv;
 556         int i;
 557
 558         log_remove_callback(telnet_log_callback, connection);
 559
 560         if (t_con->prompt)
 561         {
 562                 free(t_con->prompt);
 563                 t_con->prompt = NULL;
 564         }
 565
 566         for (i = 0; i < TELNET_LINE_HISTORY_SIZE; i++)
 567         {
 568                 if (t_con->history[i])
 569                 {
 570                         free(t_con->history[i]);
 571                         t_con->history[i] = NULL;
 572                 }
 573         }
 574
 575         /* if this connection registered a debug-message receiver delete it */
 576         delete_debug_msg_receiver(connection->cmd_ctx, NULL);
 577
 578         if (connection->priv)
 579         {
 580                 free(connection->priv);
 581                 connection->priv = NULL;
 582         }
 583         else
 584         {
 585                 LOG_ERROR("BUG: connection->priv == NULL");
 586         }
 587
 588         return ERROR_OK;
 589 }
 590
 591 int telnet_set_prompt(connection_t *connection, char *prompt)
 592 {
 593         telnet_connection_t *t_con = connection->priv;
 594
 595         if (t_con->prompt != NULL)
 596                 free(t_con->prompt);
 597
 598         t_con->prompt = strdup(prompt);
 599
 600         return ERROR_OK;
 601 }
 602
 603 int telnet_init(char *banner)
 604 {
 605         telnet_service_t *telnet_service = malloc(sizeof(telnet_service_t));
 606
 607         if (telnet_port == 0)
 608         {
 609                 LOG_WARNING("no telnet port specified, using default port 4444");
 610                 telnet_port = 4444;
 611         }
 612
 613         telnet_service->banner = banner;
 614
 615         add_service("telnet", CONNECTION_TELNET, telnet_port, 1, telnet_new_connection, telnet_input, telnet_connection_closed, telnet_service);
 616
 617         return ERROR_OK;
 618 }
 619
 620 int telnet_register_commands(command_context_t *command_context)
 621 {
 622         register_command(command_context, NULL, "exit", handle_exit_command,
 623                                          COMMAND_EXEC, "exit telnet session");
 624
 625         register_command(command_context, NULL, "telnet_port", handle_telnet_port_command,
 626                                          COMMAND_CONFIG, "");
 627
 628         return ERROR_OK;
 629 }
 630
 631 /* daemon configuration command telnet_port */
 632 int handle_telnet_port_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
 633 {
 634         if (argc == 0)
 635                 return ERROR_OK;
 636
 637         telnet_port = strtoul(args[0], NULL, 0);
 638
 639         return ERROR_OK;
 640 }
 641
 642 int handle_exit_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
 643 {
 644         return ERROR_COMMAND_CLOSE_CONNECTION;
 645 }