1 /***************************************************************************
2 * Copyright (C) 2005 by Dominic Rath *
3 * Dominic.Rath@gmx.de *
5 * This program is free software; you can redistribute it and/or modify *
6 * it under the terms of the GNU General Public License as published by *
7 * the Free Software Foundation; either version 2 of the License, or *
8 * (at your option) any later version. *
10 * This program is distributed in the hope that it will be useful, *
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of *
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the *
13 * GNU General Public License for more details. *
15 * You should have received a copy of the GNU General Public License *
16 * along with this program; if not, write to the *
17 * Free Software Foundation, Inc., *
18 * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. *
19 ***************************************************************************/
24 #include "replacements.h"
26 #include "telnet_server.h"
32 #include "target_request.h"
40 static unsigned short telnet_port = 0;
42 int handle_exit_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc);
43 int handle_telnet_port_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc);
45 static char *negotiate =
46 "\xFF\xFB\x03" /* IAC WILL Suppress Go Ahead */
47 "\xFF\xFB\x01" /* IAC WILL Echo */
48 "\xFF\xFD\x03" /* IAC DO Suppress Go Ahead */
49 "\xFF\xFE\x01"; /* IAC DON'T Echo */
51 #define CTRL(c) (c - '@')
54 /* The only way we can detect that the socket is closed is the first time
55 * we write to it, we will fail. Subsequent write operations will
58 int telnet_write(connection_t *connection, void *data, int len)
60 telnet_connection_t *t_con = connection->priv;
62 return ERROR_SERVER_REMOTE_CLOSED;
64 if (write_socket(connection->fd, data, len)==len)
69 return ERROR_SERVER_REMOTE_CLOSED;
73 int telnet_prompt(connection_t *connection)
75 telnet_connection_t *t_con = connection->priv;
77 return telnet_write(connection, t_con->prompt, strlen(t_con->prompt));
80 int telnet_outputline(connection_t *connection, char* line)
82 telnet_write(connection, line, strlen(line));
83 return telnet_write(connection, "\r\n\0", 3);
87 int telnet_output(struct command_context_s *cmd_ctx, char* line)
89 connection_t *connection = cmd_ctx->output_handler_priv;
91 return telnet_outputline(connection, line);
94 void telnet_log_callback(void *priv, const char *file, int line,
95 const char *function, const char *format, va_list args)
97 connection_t *connection = priv;
98 char *t=allocPrintf(format, args);
102 telnet_outputline(connection, t);
108 int telnet_target_callback_event_handler(struct target_s *target, enum target_event event, void *priv)
110 struct command_context_s *cmd_ctx = priv;
115 case TARGET_EVENT_HALTED:
116 command_print(cmd_ctx, "Target %i halted", get_num_by_target(target));
117 target->type->arch_state(target, buffer, 512);
119 command_print(cmd_ctx, "%s", buffer);
121 case TARGET_EVENT_RESUMED:
122 command_print(cmd_ctx, "Target %i resumed", get_num_by_target(target));
131 int telnet_new_connection(connection_t *connection)
133 telnet_connection_t *telnet_connection = malloc(sizeof(telnet_connection_t));
134 telnet_service_t *telnet_service = connection->service->priv;
137 connection->priv = telnet_connection;
139 /* initialize telnet connection information */
140 telnet_connection->closed = 0;
141 telnet_connection->line_size = 0;
142 telnet_connection->line_cursor = 0;
143 telnet_connection->option_size = 0;
144 telnet_connection->prompt = strdup("> ");
145 telnet_connection->state = TELNET_STATE_DATA;
147 /* output goes through telnet connection */
148 command_set_output_handler(connection->cmd_ctx, telnet_output, connection);
150 /* negotiate telnet options */
151 telnet_write(connection, negotiate, strlen(negotiate));
153 /* print connection banner */
154 if (telnet_service->banner)
156 telnet_write(connection, telnet_service->banner, strlen(telnet_service->banner));
157 telnet_write(connection, "\r\n\0", 3);
160 telnet_prompt(connection);
162 /* initialize history */
163 for (i = 0; i < TELNET_LINE_HISTORY_SIZE; i++)
165 telnet_connection->history[i] = NULL;
167 telnet_connection->next_history = 0;
168 telnet_connection->current_history = 0;
170 target_register_event_callback(telnet_target_callback_event_handler, connection->cmd_ctx);
175 void telnet_clear_line(connection_t *connection, telnet_connection_t *t_con)
177 /* move to end of line */
178 if (t_con->line_cursor < t_con->line_size)
180 telnet_write(connection, t_con->line + t_con->line_cursor, t_con->line_size - t_con->line_cursor);
183 /* backspace, overwrite with space, backspace */
184 while (t_con->line_size > 0)
186 telnet_write(connection, "\b \b", 3);
189 t_con->line_cursor = 0;
192 int telnet_input(connection_t *connection)
195 char buffer[TELNET_BUFFER_SIZE];
197 telnet_connection_t *t_con = connection->priv;
198 command_context_t *command_context = connection->cmd_ctx;
200 bytes_read = read_socket(connection->fd, buffer, TELNET_BUFFER_SIZE);
203 return ERROR_SERVER_REMOTE_CLOSED;
204 else if (bytes_read == -1)
206 ERROR("error during read: %s", strerror(errno));
207 return ERROR_SERVER_REMOTE_CLOSED;
213 switch (t_con->state)
215 case TELNET_STATE_DATA:
216 if (*buf_p == '\xff')
218 t_con->state = TELNET_STATE_IAC;
222 if (isprint(*buf_p)) /* printable character */
224 telnet_write(connection, buf_p, 1);
225 if (t_con->line_cursor == t_con->line_size)
227 t_con->line[t_con->line_size++] = *buf_p;
228 t_con->line_cursor++;
233 memmove(t_con->line + t_con->line_cursor + 1, t_con->line + t_con->line_cursor, t_con->line_size - t_con->line_cursor);
234 t_con->line[t_con->line_cursor++] = *buf_p;
236 telnet_write(connection, t_con->line + t_con->line_cursor, t_con->line_size - t_con->line_cursor);
237 for (i = t_con->line_cursor; i < t_con->line_size; i++)
239 telnet_write(connection, "\b", 1);
243 else /* non-printable */
245 if (*buf_p == 0x1b) /* escape */
247 t_con->state = TELNET_STATE_ESCAPE;
248 t_con->last_escape = '\x00';
250 else if ((*buf_p == 0xd) || (*buf_p == 0xa)) /* CR/LF */
254 /* skip over combinations with CR/LF + NUL */
255 if (((*(buf_p + 1) == 0xa) || (*(buf_p + 1) == 0xd)) && (bytes_read > 1))
260 if ((*(buf_p + 1) == 0) && (bytes_read > 1))
265 t_con->line[t_con->line_size] = 0;
267 telnet_write(connection, "\r\n\x00", 3);
269 if (strcmp(t_con->line, "history") == 0)
272 for (i = 0; i < TELNET_LINE_HISTORY_SIZE; i++)
274 if (t_con->history[i])
276 telnet_write(connection, t_con->history[i], strlen(t_con->history[i]));
277 telnet_write(connection, "\r\n\x00", 3);
280 telnet_prompt(connection);
281 t_con->line_size = 0;
282 t_con->line_cursor = 0;
286 log_setCallback(telnet_log_callback, connection);
288 if ((retval = command_run_line(command_context, t_con->line)) != ERROR_OK)
290 if (retval == ERROR_COMMAND_CLOSE_CONNECTION)
292 return ERROR_SERVER_REMOTE_CLOSED;
296 /* Save only non-blank lines in the history */
297 if (t_con->line_size > 0)
299 /* if the history slot is already taken, free it */
300 if (t_con->history[t_con->next_history])
302 free(t_con->history[t_con->next_history]);
305 /* add line to history */
306 t_con->history[t_con->next_history] = strdup(t_con->line);
308 /* wrap history at TELNET_LINE_HISTORY_SIZE */
309 t_con->next_history = (t_con->next_history + 1) % TELNET_LINE_HISTORY_SIZE;
311 /* current history line starts at the new entry */
312 t_con->current_history = t_con->next_history;
314 if (t_con->history[t_con->current_history])
316 free(t_con->history[t_con->current_history]);
318 t_con->history[t_con->current_history] = strdup("");
321 int t=telnet_prompt(connection);
322 if (t==ERROR_SERVER_REMOTE_CLOSED)
325 t_con->line_size = 0;
326 t_con->line_cursor = 0;
328 else if ((*buf_p == 0x7f) || (*buf_p == 0x8)) /* delete character */
330 if (t_con->line_cursor > 0)
332 if (t_con->line_cursor != t_con->line_size)
335 telnet_write(connection, "\b", 1);
336 t_con->line_cursor--;
338 memmove(t_con->line + t_con->line_cursor, t_con->line + t_con->line_cursor + 1, t_con->line_size - t_con->line_cursor);
340 telnet_write(connection, t_con->line + t_con->line_cursor, t_con->line_size - t_con->line_cursor);
341 telnet_write(connection, " \b", 2);
342 for (i = t_con->line_cursor; i < t_con->line_size; i++)
344 telnet_write(connection, "\b", 1);
350 t_con->line_cursor--;
351 /* back space: move the 'printer' head one char back, overwrite with space, move back again */
352 telnet_write(connection, "\b \b", 3);
356 else if (*buf_p == 0x15) /* clear line */
358 telnet_clear_line(connection, t_con);
360 else if (*buf_p == CTRL('B')) /* cursor left */
362 if (t_con->line_cursor > 0)
364 telnet_write(connection, "\b", 1);
365 t_con->line_cursor--;
367 t_con->state = TELNET_STATE_DATA;
369 else if (*buf_p == CTRL('F')) /* cursor right */
371 if (t_con->line_cursor < t_con->line_size)
373 telnet_write(connection, t_con->line + t_con->line_cursor++, 1);
375 t_con->state = TELNET_STATE_DATA;
379 DEBUG("unhandled nonprintable: %2.2x", *buf_p);
384 case TELNET_STATE_IAC:
388 t_con->state = TELNET_STATE_DONT;
391 t_con->state = TELNET_STATE_DO;
394 t_con->state = TELNET_STATE_WONT;
397 t_con->state = TELNET_STATE_WILL;
401 case TELNET_STATE_SB:
403 case TELNET_STATE_SE:
405 case TELNET_STATE_WILL:
406 case TELNET_STATE_WONT:
407 case TELNET_STATE_DO:
408 case TELNET_STATE_DONT:
409 t_con->state = TELNET_STATE_DATA;
411 case TELNET_STATE_ESCAPE:
412 if (t_con->last_escape == '[')
414 if (*buf_p == 'D') /* cursor left */
416 if (t_con->line_cursor > 0)
418 telnet_write(connection, "\b", 1);
419 t_con->line_cursor--;
421 t_con->state = TELNET_STATE_DATA;
423 else if (*buf_p == 'C') /* cursor right */
425 if (t_con->line_cursor < t_con->line_size)
427 telnet_write(connection, t_con->line + t_con->line_cursor++, 1);
429 t_con->state = TELNET_STATE_DATA;
431 else if (*buf_p == 'A') /* cursor up */
433 int last_history = (t_con->current_history > 0) ? t_con->current_history - 1 : TELNET_LINE_HISTORY_SIZE-1;
434 if (t_con->history[last_history])
436 telnet_clear_line(connection, t_con);
437 t_con->line_size = strlen(t_con->history[last_history]);
438 t_con->line_cursor = t_con->line_size;
439 memcpy(t_con->line, t_con->history[last_history], t_con->line_size + 1);
440 telnet_write(connection, t_con->line, t_con->line_size);
441 t_con->current_history = last_history;
443 t_con->state = TELNET_STATE_DATA;
445 else if (*buf_p == 'B') /* cursor down */
447 int next_history = (t_con->current_history + 1) % TELNET_LINE_HISTORY_SIZE;
448 if (t_con->history[next_history])
450 telnet_clear_line(connection, t_con);
451 t_con->line_size = strlen(t_con->history[next_history]);
452 t_con->line_cursor = t_con->line_size;
453 memcpy(t_con->line, t_con->history[next_history], t_con->line_size + 1);
454 telnet_write(connection, t_con->line, t_con->line_size);
455 t_con->current_history = next_history;
457 t_con->state = TELNET_STATE_DATA;
459 else if (*buf_p == '3')
461 t_con->last_escape = *buf_p;
465 t_con->state = TELNET_STATE_DATA;
468 else if (t_con->last_escape == '3')
470 /* Remove character */
473 if (t_con->line_cursor < t_con->line_size)
477 /* remove char from line buffer */
478 memmove(t_con->line + t_con->line_cursor, t_con->line + t_con->line_cursor + 1, t_con->line_size - t_con->line_cursor);
480 /* print remainder of buffer */
481 telnet_write(connection, t_con->line + t_con->line_cursor, t_con->line_size - t_con->line_cursor);
482 /* overwrite last char with whitespace */
483 telnet_write(connection, " \b", 2);
485 /* move back to cursor position*/
486 for (i = t_con->line_cursor; i < t_con->line_size; i++)
488 telnet_write(connection, "\b", 1);
492 t_con->state = TELNET_STATE_DATA;
496 t_con->state = TELNET_STATE_DATA;
499 else if (t_con->last_escape == '\x00')
503 t_con->last_escape = *buf_p;
507 t_con->state = TELNET_STATE_DATA;
512 ERROR("BUG: unexpected value in t_con->last_escape");
513 t_con->state = TELNET_STATE_DATA;
518 ERROR("unknown telnet state");
529 int telnet_connection_closed(connection_t *connection)
531 telnet_connection_t *t_con = connection->priv;
537 t_con->prompt = NULL;
540 for (i = 0; i < TELNET_LINE_HISTORY_SIZE; i++)
542 if (t_con->history[i])
544 free(t_con->history[i]);
545 t_con->history[i] = NULL;
549 /* if this connection registered a debug-message receiver delete it */
550 delete_debug_msg_receiver(connection->cmd_ctx, NULL);
552 if (connection->priv)
554 free(connection->priv);
555 connection->priv = NULL;
559 ERROR("BUG: connection->priv == NULL");
562 target_unregister_event_callback(telnet_target_callback_event_handler, connection->cmd_ctx);
567 int telnet_set_prompt(connection_t *connection, char *prompt)
569 telnet_connection_t *t_con = connection->priv;
571 t_con->prompt = strdup(prompt);
576 int telnet_init(char *banner)
578 telnet_service_t *telnet_service = malloc(sizeof(telnet_service_t));
580 if (telnet_port == 0)
582 WARNING("no telnet port specified, using default port 4444");
586 telnet_service->banner = banner;
588 add_service("telnet", CONNECTION_TELNET, telnet_port, 1, telnet_new_connection, telnet_input, telnet_connection_closed, telnet_service);
593 int telnet_register_commands(command_context_t *command_context)
595 register_command(command_context, NULL, "exit", handle_exit_command,
596 COMMAND_EXEC, "exit telnet session");
598 register_command(command_context, NULL, "telnet_port", handle_telnet_port_command,
604 /* daemon configuration command telnet_port */
605 int handle_telnet_port_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
610 /* only if the port wasn't overwritten by cmdline */
611 if (telnet_port == 0)
612 telnet_port = strtoul(args[0], NULL, 0);
617 int handle_exit_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
619 return ERROR_COMMAND_CLOSE_CONNECTION;