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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  *   Copyright (C) 2008 by Spencer Oliver                                  *
   9  *   spen@spen-soft.co.uk                                                  *
  10  *                                                                         *
  11  *   This program is free software; you can redistribute it and/or modify  *
  12  *   it under the terms of the GNU General Public License as published by  *
  13  *   the Free Software Foundation; either version 2 of the License, or     *
  14  *   (at your option) any later version.                                   *
  15  *                                                                         *
  16  *   This program is distributed in the hope that it will be useful,       *
  17  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  18  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
  19  *   GNU General Public License for more details.                          *
  20  *                                                                         *
  21  *   You should have received a copy of the GNU General Public License     *
  22  *   along with this program; if not, write to the                         *
  23  *   Free Software Foundation, Inc.,                                       *
  24  *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
  25  ***************************************************************************/
  26 #ifdef HAVE_CONFIG_H
  27 #include "config.h"
  28 #endif
  29
  30 #include "replacements.h"
  31
  32 #include "telnet_server.h"
  33
  34 #include "server.h"
  35 #include "log.h"
  36 #include "command.h"
  37 #include "target.h"
  38 #include "target_request.h"
  39
  40 #include <stdlib.h>
  41 #include <unistd.h>
  42 #include <errno.h>
  43 #include <string.h>
  44 #include <ctype.h>
  45
  46 static unsigned short telnet_port = 0;
  47
  48 int handle_exit_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc);
  49 int handle_telnet_port_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc);
  50
  51 static int telnet_async()
  52 {
  53         return jim_global_long("telnet_async_state");
  54 }
  55
  56 static char *negotiate =
  57                 "\xFF\xFB\x03"          /* IAC WILL Suppress Go Ahead */
  58                 "\xFF\xFB\x01"          /* IAC WILL Echo */
  59                 "\xFF\xFD\x03"          /* IAC DO Suppress Go Ahead */
  60                 "\xFF\xFE\x01";         /* IAC DON'T Echo */
  61
  62 #define CTRL(c) (c - '@')
  63
  64 /* The only way we can detect that the socket is closed is the first time
  65  * we write to it, we will fail. Subsequent write operations will
  66  * succeed. Shudder!
  67  */
  68 int telnet_write(connection_t *connection, const void *data, int len)
  69 {
  70         telnet_connection_t *t_con = connection->priv;
  71         if (t_con->closed)
  72                 return ERROR_SERVER_REMOTE_CLOSED;
  73
  74         if (write_socket(connection->fd, data, len) == len)
  75         {
  76                 return ERROR_OK;
  77         }
  78         t_con->closed = 1;
  79         return ERROR_SERVER_REMOTE_CLOSED;
  80 }
  81
  82 int telnet_prompt(connection_t *connection)
  83 {
  84         telnet_connection_t *t_con = connection->priv;
  85
  86         telnet_write(connection, "\r", 1); /* the prompt is always placed at the line beginning */
  87         return telnet_write(connection, t_con->prompt, strlen(t_con->prompt));
  88 }
  89
  90 int telnet_outputline(connection_t *connection, const char *line)
  91 {
  92         int len;
  93
  94         /* process lines in buffer */
  95         while (*line) {
  96                 char *line_end = strchr(line, '\n');
  97
  98                 if (line_end)
  99                         len = line_end-line;
 100                 else
 101                         len = strlen(line);
 102
 103                 telnet_write(connection, line, len);
 104                 if (line_end)
 105                 {
 106                         telnet_write(connection, "\r\n", 2);
 107                         line += len+1;
 108                 }
 109                 else
 110                 {
 111                         line += len;
 112                 }
 113         }
 114
 115         return ERROR_OK;
 116 }
 117
 118 int telnet_output(struct command_context_s *cmd_ctx, const char* line)
 119 {
 120         connection_t *connection = cmd_ctx->output_handler_priv;
 121
 122         return telnet_outputline(connection, line);
 123 }
 124
 125 void telnet_log_callback(void *priv, const char *file, int line,
 126                 const char *function, const char *string)
 127 {
 128         connection_t *connection = priv;
 129         telnet_connection_t *t_con = connection->priv;
 130         int i;
 131
 132         /* if there is no prompt, simply output the message */
 133         if (t_con->line_cursor < 0)
 134         {
 135                 telnet_outputline(connection, string);
 136                 return;
 137         }
 138
 139         /* clear the command line */
 140         telnet_write(connection, "\r", 1);
 141         for (i = strlen(t_con->prompt) + t_con->line_size; i>0; i-=16)
 142                 telnet_write(connection, "                ", i>16 ? 16 : i);
 143         telnet_write(connection, "\r", 1);
 144
 145         /* output the message */
 146         telnet_outputline(connection, string);
 147
 148         /* put the command line to its previous state */
 149         telnet_prompt(connection);
 150         telnet_write(connection, t_con->line, t_con->line_size);
 151         for (i=t_con->line_size; i>t_con->line_cursor; i--)
 152                 telnet_write(connection, "\b", 1);
 153 }
 154
 155 int telnet_new_connection(connection_t *connection)
 156 {
 157         telnet_connection_t *telnet_connection = malloc(sizeof(telnet_connection_t));
 158         telnet_service_t *telnet_service = connection->service->priv;
 159         int i;
 160
 161         connection->priv = telnet_connection;
 162
 163         /* initialize telnet connection information */
 164         telnet_connection->closed = 0;
 165         telnet_connection->line_size = 0;
 166         telnet_connection->line_cursor = 0;
 167         telnet_connection->option_size = 0;
 168         telnet_connection->prompt = strdup("> ");
 169         telnet_connection->state = TELNET_STATE_DATA;
 170
 171         /* output goes through telnet connection */
 172         command_set_output_handler(connection->cmd_ctx, telnet_output, connection);
 173
 174         /* negotiate telnet options */
 175         telnet_write(connection, negotiate, strlen(negotiate));
 176
 177         /* print connection banner */
 178         if (telnet_service->banner)
 179         {
 180                 telnet_write(connection, telnet_service->banner, strlen(telnet_service->banner));
 181                 telnet_write(connection, "\r\n", 2);
 182         }
 183
 184         telnet_prompt(connection);
 185
 186         /* initialize history */
 187         for (i = 0; i < TELNET_LINE_HISTORY_SIZE; i++)
 188         {
 189                 telnet_connection->history[i] = NULL;
 190         }
 191         telnet_connection->next_history = 0;
 192         telnet_connection->current_history = 0;
 193
 194         if (telnet_async())
 195                 log_add_callback(telnet_log_callback, connection);
 196
 197
 198
 199         return ERROR_OK;
 200 }
 201
 202 void telnet_clear_line(connection_t *connection, telnet_connection_t *t_con)
 203 {
 204         /* move to end of line */
 205         if (t_con->line_cursor < t_con->line_size)
 206         {
 207                 telnet_write(connection, t_con->line + t_con->line_cursor, t_con->line_size - t_con->line_cursor);
 208         }
 209
 210         /* backspace, overwrite with space, backspace */
 211         while (t_con->line_size > 0)
 212         {
 213                 telnet_write(connection, "\b \b", 3);
 214                 t_con->line_size--;
 215         }
 216         t_con->line_cursor = 0;
 217 }
 218
 219 int telnet_input(connection_t *connection)
 220 {
 221         int bytes_read;
 222         char buffer[TELNET_BUFFER_SIZE];
 223         char *buf_p;
 224         telnet_connection_t *t_con = connection->priv;
 225         command_context_t *command_context = connection->cmd_ctx;
 226
 227         bytes_read = read_socket(connection->fd, buffer, TELNET_BUFFER_SIZE);
 228
 229         if (bytes_read == 0)
 230                 return ERROR_SERVER_REMOTE_CLOSED;
 231         else if (bytes_read == -1)
 232         {
 233                 LOG_ERROR("error during read: %s", strerror(errno));
 234                 return ERROR_SERVER_REMOTE_CLOSED;
 235         }
 236
 237         buf_p = buffer;
 238         while (bytes_read)
 239         {
 240                 switch (t_con->state)
 241                 {
 242                         case TELNET_STATE_DATA:
 243                                 if (*buf_p == '\xff')
 244                                 {
 245                                         t_con->state = TELNET_STATE_IAC;
 246                                 }
 247                                 else
 248                                 {
 249                                         if (isprint(*buf_p)) /* printable character */
 250                                         {
 251                                                 /* watch buffer size leaving one spare character for string null termination */
 252                                                 if (t_con->line_size == TELNET_LINE_MAX_SIZE-1)
 253                                                 {
 254                                                         /* output audible bell if buffer is full */
 255                                                         telnet_write(connection, "\x07", 1); /* "\a" does not work, at least on windows */
 256                                                 }
 257                                                 else if (t_con->line_cursor == t_con->line_size)
 258                                                 {
 259                                                         telnet_write(connection, buf_p, 1);
 260                                                         t_con->line[t_con->line_size++] = *buf_p;
 261                                                         t_con->line_cursor++;
 262                                                 }
 263                                                 else
 264                                                 {
 265                                                         int i;
 266                                                         memmove(t_con->line + t_con->line_cursor + 1, t_con->line + t_con->line_cursor, t_con->line_size - t_con->line_cursor);
 267                                                         t_con->line[t_con->line_cursor] = *buf_p;
 268                                                         t_con->line_size++;
 269                                                         telnet_write(connection, t_con->line + t_con->line_cursor, t_con->line_size - t_con->line_cursor);
 270                                                         t_con->line_cursor++;
 271                                                         for (i = t_con->line_cursor; i < t_con->line_size; i++)
 272                                                         {
 273                                                                 telnet_write(connection, "\b", 1);
 274                                                         }
 275                                                 }
 276                                         }
 277                                         else /* non-printable */
 278                                         {
 279                                                 if (*buf_p == 0x1b) /* escape */
 280                                                 {
 281                                                         t_con->state = TELNET_STATE_ESCAPE;
 282                                                         t_con->last_escape = '\x00';
 283                                                 }
 284                                                 else if ((*buf_p == 0xd) || (*buf_p == 0xa)) /* CR/LF */
 285                                                 {
 286                                                         int retval;
 287
 288                                                         /* skip over combinations with CR/LF and NUL characters */
 289                                                         if ((bytes_read > 1) && ((*(buf_p + 1) == 0xa) || (*(buf_p + 1) == 0xd)))
 290                                                         {
 291                                                                 buf_p++;
 292                                                                 bytes_read--;
 293                                                         }
 294                                                         if ((bytes_read > 1) && (*(buf_p + 1) == 0))
 295                                                         {
 296                                                                 buf_p++;
 297                                                                 bytes_read--;
 298                                                         }
 299                                                         t_con->line[t_con->line_size] = 0;
 300
 301                                                         telnet_write(connection, "\r\n\x00", 3);
 302
 303                                                         if (strcmp(t_con->line, "history") == 0)
 304                                                         {
 305                                                                 int i;
 306                                                                 for (i = 1; i < TELNET_LINE_HISTORY_SIZE; i++)
 307                                                                 {
 308                                                                         /* the t_con->next_history line contains empty string (unless NULL), thus it is not printed */
 309                                                                         char *history_line = t_con->history[(t_con->next_history + i) % TELNET_LINE_HISTORY_SIZE];
 310                                                                         if (history_line)
 311                                                                         {
 312                                                                                 telnet_write(connection, history_line, strlen(history_line));
 313                                                                                 telnet_write(connection, "\r\n\x00", 3);
 314                                                                         }
 315                                                                 }
 316                                                                 t_con->line_size = 0;
 317                                                                 t_con->line_cursor = 0;
 318                                                                 continue;
 319                                                         }
 320
 321                                                         /* save only non-blank not repeating lines in the history */
 322                                                         char *prev_line = t_con->history[(t_con->current_history > 0) ? t_con->current_history - 1 : TELNET_LINE_HISTORY_SIZE-1];
 323                                                         if (*t_con->line && (prev_line == NULL || strcmp(t_con->line, prev_line)))
 324                                                         {
 325                                                                 /* if the history slot is already taken, free it */
 326                                                                 if (t_con->history[t_con->next_history])
 327                                                                 {
 328                                                                         free(t_con->history[t_con->next_history]);
 329                                                                 }
 330
 331                                                                 /* add line to history */
 332                                                                 t_con->history[t_con->next_history] = strdup(t_con->line);
 333
 334                                                                 /* wrap history at TELNET_LINE_HISTORY_SIZE */
 335                                                                 t_con->next_history = (t_con->next_history + 1) % TELNET_LINE_HISTORY_SIZE;
 336
 337                                                                 /* current history line starts at the new entry */
 338                                                                 t_con->current_history = t_con->next_history;
 339
 340                                                                 if (t_con->history[t_con->current_history])
 341                                                                 {
 342                                                                         free(t_con->history[t_con->current_history]);
 343                                                                 }
 344                                                                 t_con->history[t_con->current_history] = strdup("");
 345                                                         }
 346
 347                                                         t_con->line_size = 0;
 348
 349                                                         t_con->line_cursor = -1; /* to supress prompt in log callback during command execution */
 350
 351                                                         if (!telnet_async())
 352                                                                 log_add_callback(telnet_log_callback, connection);
 353
 354                                                         retval = command_run_line(command_context, t_con->line);
 355
 356                                                         if (!telnet_async())
 357                                                                 log_remove_callback(telnet_log_callback, connection);
 358
 359                                                         t_con->line_cursor = 0;
 360
 361                                                         if (retval == ERROR_COMMAND_CLOSE_CONNECTION)
 362                                                                 return ERROR_SERVER_REMOTE_CLOSED;
 363
 364                                                         retval = telnet_prompt(connection);
 365                                                         if (retval == ERROR_SERVER_REMOTE_CLOSED)
 366                                                                 return ERROR_SERVER_REMOTE_CLOSED;
 367
 368                                                 }
 369                                                 else if ((*buf_p == 0x7f) || (*buf_p == 0x8)) /* delete character */
 370                                                 {
 371                                                         if (t_con->line_cursor > 0)
 372                                                         {
 373                                                                 if (t_con->line_cursor != t_con->line_size)
 374                                                                 {
 375                                                                         int i;
 376                                                                         telnet_write(connection, "\b", 1);
 377                                                                         t_con->line_cursor--;
 378                                                                         t_con->line_size--;
 379                                                                         memmove(t_con->line + t_con->line_cursor, t_con->line + t_con->line_cursor + 1, t_con->line_size - t_con->line_cursor);
 380
 381                                                                         telnet_write(connection, t_con->line + t_con->line_cursor, t_con->line_size - t_con->line_cursor);
 382                                                                         telnet_write(connection, " \b", 2);
 383                                                                         for (i = t_con->line_cursor; i < t_con->line_size; i++)
 384                                                                         {
 385                                                                                 telnet_write(connection, "\b", 1);
 386                                                                         }
 387                                                                 }
 388                                                                 else
 389                                                                 {
 390                                                                         t_con->line_size--;
 391                                                                         t_con->line_cursor--;
 392                                                                         /* back space: move the 'printer' head one char back, overwrite with space, move back again */
 393                                                                         telnet_write(connection, "\b \b", 3);
 394                                                                 }
 395                                                         }
 396                                                 }
 397                                                 else if (*buf_p == 0x15) /* clear line */
 398                                                 {
 399                                                         telnet_clear_line(connection, t_con);
 400                                                 }
 401                                                 else if (*buf_p == CTRL('B')) /* cursor left */
 402                                                 {
 403                                                         if (t_con->line_cursor > 0)
 404                                                         {
 405                                                                 telnet_write(connection, "\b", 1);
 406                                                                 t_con->line_cursor--;
 407                                                         }
 408                                                         t_con->state = TELNET_STATE_DATA;
 409                                                 }
 410                                                 else if (*buf_p == CTRL('F')) /* cursor right */
 411                                                 {
 412                                                         if (t_con->line_cursor < t_con->line_size)
 413                                                         {
 414                                                                 telnet_write(connection, t_con->line + t_con->line_cursor++, 1);
 415                                                         }
 416                                                         t_con->state = TELNET_STATE_DATA;
 417                                                 }
 418                                                 else
 419                                                 {
 420                                                         LOG_DEBUG("unhandled nonprintable: %2.2x", *buf_p);
 421                                                 }
 422                                         }
 423                                 }
 424                                 break;
 425                         case TELNET_STATE_IAC:
 426                                 switch (*buf_p)
 427                                 {
 428                                         case '\xfe':
 429                                                 t_con->state = TELNET_STATE_DONT;
 430                                                 break;
 431                                         case '\xfd':
 432                                                 t_con->state = TELNET_STATE_DO;
 433                                                 break;
 434                                         case '\xfc':
 435                                                 t_con->state = TELNET_STATE_WONT;
 436                                                 break;
 437                                         case '\xfb':
 438                                                 t_con->state = TELNET_STATE_WILL;
 439                                                 break;
 440                                 }
 441                                 break;
 442                         case TELNET_STATE_SB:
 443                                 break;
 444                         case TELNET_STATE_SE:
 445                                 break;
 446                         case TELNET_STATE_WILL:
 447                         case TELNET_STATE_WONT:
 448                         case TELNET_STATE_DO:
 449                         case TELNET_STATE_DONT:
 450                                 t_con->state = TELNET_STATE_DATA;
 451                                 break;
 452                         case TELNET_STATE_ESCAPE:
 453                                 if (t_con->last_escape == '[')
 454                                 {
 455                                         if (*buf_p == 'D') /* cursor left */
 456                                         {
 457                                                 if (t_con->line_cursor > 0)
 458                                                 {
 459                                                         telnet_write(connection, "\b", 1);
 460                                                         t_con->line_cursor--;
 461                                                 }
 462                                                 t_con->state = TELNET_STATE_DATA;
 463                                         }
 464                                         else if (*buf_p == 'C') /* cursor right */
 465                                         {
 466                                                 if (t_con->line_cursor < t_con->line_size)
 467                                                 {
 468                                                         telnet_write(connection, t_con->line + t_con->line_cursor++, 1);
 469                                                 }
 470                                                 t_con->state = TELNET_STATE_DATA;
 471                                         }
 472                                         else if (*buf_p == 'A') /* cursor up */
 473                                         {
 474                                                 int last_history = (t_con->current_history > 0) ? t_con->current_history - 1 : TELNET_LINE_HISTORY_SIZE-1;
 475                                                 if (t_con->history[last_history])
 476                                                 {
 477                                                         telnet_clear_line(connection, t_con);
 478                                                         t_con->line_size = strlen(t_con->history[last_history]);
 479                                                         t_con->line_cursor = t_con->line_size;
 480                                                         memcpy(t_con->line, t_con->history[last_history], t_con->line_size);
 481                                                         telnet_write(connection, t_con->line, t_con->line_size);
 482                                                         t_con->current_history = last_history;
 483                                                 }
 484                                                 t_con->state = TELNET_STATE_DATA;
 485                                         }
 486                                         else if (*buf_p == 'B') /* cursor down */
 487                                         {
 488                                                 int next_history = (t_con->current_history + 1) % TELNET_LINE_HISTORY_SIZE;
 489                                                 if (t_con->history[next_history])
 490                                                 {
 491                                                         telnet_clear_line(connection, t_con);
 492                                                         t_con->line_size = strlen(t_con->history[next_history]);
 493                                                         t_con->line_cursor = t_con->line_size;
 494                                                         memcpy(t_con->line, t_con->history[next_history], t_con->line_size);
 495                                                         telnet_write(connection, t_con->line, t_con->line_size);
 496                                                         t_con->current_history = next_history;
 497                                                 }
 498                                                 t_con->state = TELNET_STATE_DATA;
 499                                         }
 500                                         else if (*buf_p == '3')
 501                                         {
 502                                                 t_con->last_escape = *buf_p;
 503                                         }
 504                                         else
 505                                         {
 506                                                 t_con->state = TELNET_STATE_DATA;
 507                                         }
 508                                 }
 509                                 else if (t_con->last_escape == '3')
 510                                 {
 511                                         /* Remove character */
 512                                         if (*buf_p == '~')
 513                                         {
 514                                                 if (t_con->line_cursor < t_con->line_size)
 515                                                 {
 516                                                         int i;
 517                                                         t_con->line_size--;
 518                                                         /* remove char from line buffer */
 519                                                         memmove(t_con->line + t_con->line_cursor, t_con->line + t_con->line_cursor + 1, t_con->line_size - t_con->line_cursor);
 520
 521                                                         /* print remainder of buffer */
 522                                                         telnet_write(connection, t_con->line + t_con->line_cursor, t_con->line_size - t_con->line_cursor);
 523                                                         /* overwrite last char with whitespace */
 524                                                         telnet_write(connection, " \b", 2);
 525
 526                                                         /* move back to cursor position*/
 527                                                         for (i = t_con->line_cursor; i < t_con->line_size; i++)
 528                                                         {
 529                                                                 telnet_write(connection, "\b", 1);
 530                                                         }
 531                                                 }
 532
 533                                                 t_con->state = TELNET_STATE_DATA;
 534                                         }
 535                                         else
 536                                         {
 537                                                 t_con->state = TELNET_STATE_DATA;
 538                                         }
 539                                 }
 540                                 else if (t_con->last_escape == '\x00')
 541                                 {
 542                                         if (*buf_p == '[')
 543                                         {
 544                                                 t_con->last_escape = *buf_p;
 545                                         }
 546                                         else
 547                                         {
 548                                                 t_con->state = TELNET_STATE_DATA;
 549                                         }
 550                                 }
 551                                 else
 552                                 {
 553                                         LOG_ERROR("BUG: unexpected value in t_con->last_escape");
 554                                         t_con->state = TELNET_STATE_DATA;
 555                                 }
 556
 557                                 break;
 558                         default:
 559                                 LOG_ERROR("unknown telnet state");
 560                                 exit(-1);
 561                 }
 562
 563                 bytes_read--;
 564                 buf_p++;
 565         }
 566
 567         return ERROR_OK;
 568 }
 569
 570 int telnet_connection_closed(connection_t *connection)
 571 {
 572         telnet_connection_t *t_con = connection->priv;
 573         int i;
 574
 575         log_remove_callback(telnet_log_callback, connection);
 576
 577         if (t_con->prompt)
 578         {
 579                 free(t_con->prompt);
 580                 t_con->prompt = NULL;
 581         }
 582
 583         for (i = 0; i < TELNET_LINE_HISTORY_SIZE; i++)
 584         {
 585                 if (t_con->history[i])
 586                 {
 587                         free(t_con->history[i]);
 588                         t_con->history[i] = NULL;
 589                 }
 590         }
 591
 592         /* if this connection registered a debug-message receiver delete it */
 593         delete_debug_msg_receiver(connection->cmd_ctx, NULL);
 594
 595         if (connection->priv)
 596         {
 597                 free(connection->priv);
 598                 connection->priv = NULL;
 599         }
 600         else
 601         {
 602                 LOG_ERROR("BUG: connection->priv == NULL");
 603         }
 604
 605         return ERROR_OK;
 606 }
 607
 608 int telnet_set_prompt(connection_t *connection, char *prompt)
 609 {
 610         telnet_connection_t *t_con = connection->priv;
 611
 612         if (t_con->prompt != NULL)
 613                 free(t_con->prompt);
 614
 615         t_con->prompt = strdup(prompt);
 616
 617         return ERROR_OK;
 618 }
 619
 620 int telnet_init(char *banner)
 621 {
 622         telnet_service_t *telnet_service = malloc(sizeof(telnet_service_t));
 623
 624         if (telnet_port == 0)
 625         {
 626                 LOG_WARNING("no telnet port specified, using default port 4444");
 627                 telnet_port = 4444;
 628         }
 629
 630         telnet_service->banner = banner;
 631
 632         add_service("telnet", CONNECTION_TELNET, telnet_port, 1, telnet_new_connection, telnet_input, telnet_connection_closed, telnet_service);
 633
 634         return ERROR_OK;
 635 }
 636
 637 int telnet_register_commands(command_context_t *command_context)
 638 {
 639         register_command(command_context, NULL, "exit", handle_exit_command,
 640                                          COMMAND_EXEC, "exit telnet session");
 641
 642         register_command(command_context, NULL, "telnet_port", handle_telnet_port_command,
 643                                          COMMAND_CONFIG, "port on which to listen for incoming telnet connections");
 644
 645         return ERROR_OK;
 646 }
 647
 648 /* daemon configuration command telnet_port */
 649 int handle_telnet_port_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
 650 {
 651         if (argc == 0)
 652                 return ERROR_OK;
 653
 654         telnet_port = strtoul(args[0], NULL, 0);
 655
 656         return ERROR_OK;
 657 }
 658
 659 int handle_exit_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
 660 {
 661         return ERROR_COMMAND_CLOSE_CONNECTION;
 662 }