- convert all files to unix line-ending
[openocd.git] / src / server / telnet_server.c
1 /***************************************************************************
2 * Copyright (C) 2005 by Dominic Rath *
3 * Dominic.Rath@gmx.de *
4 * *
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. *
9 * *
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. *
14 * *
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 ***************************************************************************/
20 #ifdef HAVE_CONFIG_H
21 #include "config.h"
22 #endif
23
24 #include "replacements.h"
25
26 #include "telnet_server.h"
27
28 #include "server.h"
29 #include "log.h"
30 #include "command.h"
31 #include "target.h"
32 #include "target_request.h"
33
34 #include <stdlib.h>
35 #include <unistd.h>
36 #include <errno.h>
37 #include <string.h>
38 #include <ctype.h>
39
40 static unsigned short telnet_port = 0;
41
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);
44
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 */
50
51 #define CTRL(c) (c - '@')
52
53 /* The only way we can detect that the socket is closed is the first time
54 * we write to it, we will fail. Subsequent write operations will
55 * succeed. Shudder!
56 */
57 int telnet_write(connection_t *connection, void *data, int len)
58 {
59 telnet_connection_t *t_con = connection->priv;
60 if (t_con->closed)
61 return ERROR_SERVER_REMOTE_CLOSED;
62
63 if (write_socket(connection->fd, data, len) == len)
64 {
65 return ERROR_OK;
66 }
67 t_con->closed = 1;
68 return ERROR_SERVER_REMOTE_CLOSED;
69 }
70
71 int telnet_prompt(connection_t *connection)
72 {
73 telnet_connection_t *t_con = connection->priv;
74
75 return telnet_write(connection, t_con->prompt, strlen(t_con->prompt));
76 }
77
78 int telnet_outputline(connection_t *connection, char* line)
79 {
80 telnet_write(connection, line, strlen(line));
81 return telnet_write(connection, "\r\n\0", 3);
82 }
83
84 int telnet_output(struct command_context_s *cmd_ctx, char* line)
85 {
86 connection_t *connection = cmd_ctx->output_handler_priv;
87
88 return telnet_outputline(connection, line);
89 }
90
91 void telnet_log_callback(void *priv, const char *file, int line,
92 const char *function, const char *format, va_list args)
93 {
94 connection_t *connection = priv;
95 char *t = alloc_printf(format, args);
96 char *t2;
97 if (t == NULL)
98 return;
99 t2=t;
100 char *endline;
101 do
102 {
103 if ((endline=strchr(t2, '\n'))!=NULL)
104 {
105 *endline=0;
106 }
107 telnet_outputline(connection, t2);
108 t2=endline+1;
109 } while (endline);
110
111 free(t);
112 }
113
114 int telnet_target_callback_event_handler(struct target_s *target, enum target_event event, void *priv)
115 {
116 struct command_context_s *cmd_ctx = priv;
117 connection_t *connection = cmd_ctx->output_handler_priv;
118 telnet_connection_t *t_con = connection->priv;
119
120 switch (event)
121 {
122 case TARGET_EVENT_HALTED:
123 target_arch_state(target);
124 if (!t_con->suppress_prompt)
125 telnet_prompt(connection);
126 break;
127 case TARGET_EVENT_RESUMED:
128 if (!t_con->suppress_prompt)
129 telnet_prompt(connection);
130 break;
131 default:
132 break;
133 }
134
135 return ERROR_OK;
136 }
137
138 int telnet_new_connection(connection_t *connection)
139 {
140 telnet_connection_t *telnet_connection = malloc(sizeof(telnet_connection_t));
141 telnet_service_t *telnet_service = connection->service->priv;
142 int i;
143
144 connection->priv = telnet_connection;
145
146 /* initialize telnet connection information */
147 telnet_connection->closed = 0;
148 telnet_connection->line_size = 0;
149 telnet_connection->line_cursor = 0;
150 telnet_connection->option_size = 0;
151 telnet_connection->prompt = strdup("> ");
152 telnet_connection->suppress_prompt = 0;
153 telnet_connection->state = TELNET_STATE_DATA;
154
155 /* output goes through telnet connection */
156 command_set_output_handler(connection->cmd_ctx, telnet_output, connection);
157
158 /* negotiate telnet options */
159 telnet_write(connection, negotiate, strlen(negotiate));
160
161 /* print connection banner */
162 if (telnet_service->banner)
163 {
164 telnet_write(connection, telnet_service->banner, strlen(telnet_service->banner));
165 telnet_write(connection, "\r\n\0", 3);
166 }
167
168 telnet_prompt(connection);
169
170 /* initialize history */
171 for (i = 0; i < TELNET_LINE_HISTORY_SIZE; i++)
172 {
173 telnet_connection->history[i] = NULL;
174 }
175 telnet_connection->next_history = 0;
176 telnet_connection->current_history = 0;
177
178 target_register_event_callback(telnet_target_callback_event_handler, connection->cmd_ctx);
179
180 return ERROR_OK;
181 }
182
183 void telnet_clear_line(connection_t *connection, telnet_connection_t *t_con)
184 {
185 /* move to end of line */
186 if (t_con->line_cursor < t_con->line_size)
187 {
188 telnet_write(connection, t_con->line + t_con->line_cursor, t_con->line_size - t_con->line_cursor);
189 }
190
191 /* backspace, overwrite with space, backspace */
192 while (t_con->line_size > 0)
193 {
194 telnet_write(connection, "\b \b", 3);
195 t_con->line_size--;
196 }
197 t_con->line_cursor = 0;
198 }
199
200 int telnet_input(connection_t *connection)
201 {
202 int bytes_read;
203 char buffer[TELNET_BUFFER_SIZE];
204 char *buf_p;
205 telnet_connection_t *t_con = connection->priv;
206 command_context_t *command_context = connection->cmd_ctx;
207
208 bytes_read = read_socket(connection->fd, buffer, TELNET_BUFFER_SIZE);
209
210 if (bytes_read == 0)
211 return ERROR_SERVER_REMOTE_CLOSED;
212 else if (bytes_read == -1)
213 {
214 ERROR("error during read: %s", strerror(errno));
215 return ERROR_SERVER_REMOTE_CLOSED;
216 }
217
218 buf_p = buffer;
219 while (bytes_read)
220 {
221 switch (t_con->state)
222 {
223 case TELNET_STATE_DATA:
224 if (*buf_p == '\xff')
225 {
226 t_con->state = TELNET_STATE_IAC;
227 }
228 else
229 {
230 if (isprint(*buf_p)) /* printable character */
231 {
232 telnet_write(connection, buf_p, 1);
233 if (t_con->line_cursor == t_con->line_size)
234 {
235 t_con->line[t_con->line_size++] = *buf_p;
236 t_con->line_cursor++;
237 }
238 else
239 {
240 int i;
241 memmove(t_con->line + t_con->line_cursor + 1, t_con->line + t_con->line_cursor, t_con->line_size - t_con->line_cursor);
242 t_con->line[t_con->line_cursor++] = *buf_p;
243 t_con->line_size++;
244 telnet_write(connection, t_con->line + t_con->line_cursor, t_con->line_size - t_con->line_cursor);
245 for (i = t_con->line_cursor; i < t_con->line_size; i++)
246 {
247 telnet_write(connection, "\b", 1);
248 }
249 }
250 }
251 else /* non-printable */
252 {
253 if (*buf_p == 0x1b) /* escape */
254 {
255 t_con->state = TELNET_STATE_ESCAPE;
256 t_con->last_escape = '\x00';
257 }
258 else if ((*buf_p == 0xd) || (*buf_p == 0xa)) /* CR/LF */
259 {
260 int retval;
261
262 /* skip over combinations with CR/LF + NUL */
263 if (((*(buf_p + 1) == 0xa) || (*(buf_p + 1) == 0xd)) && (bytes_read > 1))
264 {
265 buf_p++;
266 bytes_read--;
267 }
268 if ((*(buf_p + 1) == 0) && (bytes_read > 1))
269 {
270 buf_p++;
271 bytes_read--;
272 }
273 t_con->line[t_con->line_size] = 0;
274
275 telnet_write(connection, "\r\n\x00", 3);
276
277 if (strcmp(t_con->line, "history") == 0)
278 {
279 int i;
280 for (i = 0; i < TELNET_LINE_HISTORY_SIZE; i++)
281 {
282 if (t_con->history[i])
283 {
284 telnet_write(connection, t_con->history[i], strlen(t_con->history[i]));
285 telnet_write(connection, "\r\n\x00", 3);
286 }
287 }
288 telnet_prompt(connection);
289 t_con->line_size = 0;
290 t_con->line_cursor = 0;
291 continue;
292 }
293
294 log_add_callback(telnet_log_callback, connection);
295 t_con->suppress_prompt = 1;
296
297 retval = command_run_line(command_context, t_con->line);
298
299 log_remove_callback(telnet_log_callback, connection);
300 t_con->suppress_prompt = 0;
301
302 if (retval == ERROR_COMMAND_CLOSE_CONNECTION)
303 {
304 return ERROR_SERVER_REMOTE_CLOSED;
305 }
306
307 /* Save only non-blank lines in the history */
308 if (t_con->line_size > 0)
309 {
310 /* if the history slot is already taken, free it */
311 if (t_con->history[t_con->next_history])
312 {
313 free(t_con->history[t_con->next_history]);
314 }
315
316 /* add line to history */
317 t_con->history[t_con->next_history] = strdup(t_con->line);
318
319 /* wrap history at TELNET_LINE_HISTORY_SIZE */
320 t_con->next_history = (t_con->next_history + 1) % TELNET_LINE_HISTORY_SIZE;
321
322 /* current history line starts at the new entry */
323 t_con->current_history = t_con->next_history;
324
325 if (t_con->history[t_con->current_history])
326 {
327 free(t_con->history[t_con->current_history]);
328 }
329 t_con->history[t_con->current_history] = strdup("");
330 }
331
332 int t = telnet_prompt(connection);
333 if (t == ERROR_SERVER_REMOTE_CLOSED)
334 return t;
335
336 t_con->line_size = 0;
337 t_con->line_cursor = 0;
338 }
339 else if ((*buf_p == 0x7f) || (*buf_p == 0x8)) /* delete character */
340 {
341 if (t_con->line_cursor > 0)
342 {
343 if (t_con->line_cursor != t_con->line_size)
344 {
345 int i;
346 telnet_write(connection, "\b", 1);
347 t_con->line_cursor--;
348 t_con->line_size--;
349 memmove(t_con->line + t_con->line_cursor, t_con->line + t_con->line_cursor + 1, t_con->line_size - t_con->line_cursor);
350
351 telnet_write(connection, t_con->line + t_con->line_cursor, t_con->line_size - t_con->line_cursor);
352 telnet_write(connection, " \b", 2);
353 for (i = t_con->line_cursor; i < t_con->line_size; i++)
354 {
355 telnet_write(connection, "\b", 1);
356 }
357 }
358 else
359 {
360 t_con->line_size--;
361 t_con->line_cursor--;
362 /* back space: move the 'printer' head one char back, overwrite with space, move back again */
363 telnet_write(connection, "\b \b", 3);
364 }
365 }
366 }
367 else if (*buf_p == 0x15) /* clear line */
368 {
369 telnet_clear_line(connection, t_con);
370 }
371 else if (*buf_p == CTRL('B')) /* cursor left */
372 {
373 if (t_con->line_cursor > 0)
374 {
375 telnet_write(connection, "\b", 1);
376 t_con->line_cursor--;
377 }
378 t_con->state = TELNET_STATE_DATA;
379 }
380 else if (*buf_p == CTRL('F')) /* cursor right */
381 {
382 if (t_con->line_cursor < t_con->line_size)
383 {
384 telnet_write(connection, t_con->line + t_con->line_cursor++, 1);
385 }
386 t_con->state = TELNET_STATE_DATA;
387 }
388 else
389 {
390 DEBUG("unhandled nonprintable: %2.2x", *buf_p);
391 }
392 }
393 }
394 break;
395 case TELNET_STATE_IAC:
396 switch (*buf_p)
397 {
398 case '\xfe':
399 t_con->state = TELNET_STATE_DONT;
400 break;
401 case '\xfd':
402 t_con->state = TELNET_STATE_DO;
403 break;
404 case '\xfc':
405 t_con->state = TELNET_STATE_WONT;
406 break;
407 case '\xfb':
408 t_con->state = TELNET_STATE_WILL;
409 break;
410 }
411 break;
412 case TELNET_STATE_SB:
413 break;
414 case TELNET_STATE_SE:
415 break;
416 case TELNET_STATE_WILL:
417 case TELNET_STATE_WONT:
418 case TELNET_STATE_DO:
419 case TELNET_STATE_DONT:
420 t_con->state = TELNET_STATE_DATA;
421 break;
422 case TELNET_STATE_ESCAPE:
423 if (t_con->last_escape == '[')
424 {
425 if (*buf_p == 'D') /* cursor left */
426 {
427 if (t_con->line_cursor > 0)
428 {
429 telnet_write(connection, "\b", 1);
430 t_con->line_cursor--;
431 }
432 t_con->state = TELNET_STATE_DATA;
433 }
434 else if (*buf_p == 'C') /* cursor right */
435 {
436 if (t_con->line_cursor < t_con->line_size)
437 {
438 telnet_write(connection, t_con->line + t_con->line_cursor++, 1);
439 }
440 t_con->state = TELNET_STATE_DATA;
441 }
442 else if (*buf_p == 'A') /* cursor up */
443 {
444 int last_history = (t_con->current_history > 0) ? t_con->current_history - 1 : TELNET_LINE_HISTORY_SIZE-1;
445 if (t_con->history[last_history])
446 {
447 telnet_clear_line(connection, t_con);
448 t_con->line_size = strlen(t_con->history[last_history]);
449 t_con->line_cursor = t_con->line_size;
450 memcpy(t_con->line, t_con->history[last_history], t_con->line_size + 1);
451 telnet_write(connection, t_con->line, t_con->line_size);
452 t_con->current_history = last_history;
453 }
454 t_con->state = TELNET_STATE_DATA;
455 }
456 else if (*buf_p == 'B') /* cursor down */
457 {
458 int next_history = (t_con->current_history + 1) % TELNET_LINE_HISTORY_SIZE;
459 if (t_con->history[next_history])
460 {
461 telnet_clear_line(connection, t_con);
462 t_con->line_size = strlen(t_con->history[next_history]);
463 t_con->line_cursor = t_con->line_size;
464 memcpy(t_con->line, t_con->history[next_history], t_con->line_size + 1);
465 telnet_write(connection, t_con->line, t_con->line_size);
466 t_con->current_history = next_history;
467 }
468 t_con->state = TELNET_STATE_DATA;
469 }
470 else if (*buf_p == '3')
471 {
472 t_con->last_escape = *buf_p;
473 }
474 else
475 {
476 t_con->state = TELNET_STATE_DATA;
477 }
478 }
479 else if (t_con->last_escape == '3')
480 {
481 /* Remove character */
482 if (*buf_p == '~')
483 {
484 if (t_con->line_cursor < t_con->line_size)
485 {
486 int i;
487 t_con->line_size--;
488 /* remove char from line buffer */
489 memmove(t_con->line + t_con->line_cursor, t_con->line + t_con->line_cursor + 1, t_con->line_size - t_con->line_cursor);
490
491 /* print remainder of buffer */
492 telnet_write(connection, t_con->line + t_con->line_cursor, t_con->line_size - t_con->line_cursor);
493 /* overwrite last char with whitespace */
494 telnet_write(connection, " \b", 2);
495
496 /* move back to cursor position*/
497 for (i = t_con->line_cursor; i < t_con->line_size; i++)
498 {
499 telnet_write(connection, "\b", 1);
500 }
501 }
502
503 t_con->state = TELNET_STATE_DATA;
504 }
505 else
506 {
507 t_con->state = TELNET_STATE_DATA;
508 }
509 }
510 else if (t_con->last_escape == '\x00')
511 {
512 if (*buf_p == '[')
513 {
514 t_con->last_escape = *buf_p;
515 }
516 else
517 {
518 t_con->state = TELNET_STATE_DATA;
519 }
520 }
521 else
522 {
523 ERROR("BUG: unexpected value in t_con->last_escape");
524 t_con->state = TELNET_STATE_DATA;
525 }
526
527 break;
528 default:
529 ERROR("unknown telnet state");
530 exit(-1);
531 }
532
533 bytes_read--;
534 buf_p++;
535 }
536
537 return ERROR_OK;
538 }
539
540 int telnet_connection_closed(connection_t *connection)
541 {
542 telnet_connection_t *t_con = connection->priv;
543 int i;
544
545 if (t_con->prompt)
546 {
547 free(t_con->prompt);
548 t_con->prompt = NULL;
549 }
550
551 for (i = 0; i < TELNET_LINE_HISTORY_SIZE; i++)
552 {
553 if (t_con->history[i])
554 {
555 free(t_con->history[i]);
556 t_con->history[i] = NULL;
557 }
558 }
559
560 /* if this connection registered a debug-message receiver delete it */
561 delete_debug_msg_receiver(connection->cmd_ctx, NULL);
562
563 if (connection->priv)
564 {
565 free(connection->priv);
566 connection->priv = NULL;
567 }
568 else
569 {
570 ERROR("BUG: connection->priv == NULL");
571 }
572
573 target_unregister_event_callback(telnet_target_callback_event_handler, connection->cmd_ctx);
574
575 return ERROR_OK;
576 }
577
578 int telnet_set_prompt(connection_t *connection, char *prompt)
579 {
580 telnet_connection_t *t_con = connection->priv;
581
582 t_con->prompt = strdup(prompt);
583
584 return ERROR_OK;
585 }
586
587 int telnet_init(char *banner)
588 {
589 telnet_service_t *telnet_service = malloc(sizeof(telnet_service_t));
590
591 if (telnet_port == 0)
592 {
593 WARNING("no telnet port specified, using default port 4444");
594 telnet_port = 4444;
595 }
596
597 telnet_service->banner = banner;
598
599 add_service("telnet", CONNECTION_TELNET, telnet_port, 1, telnet_new_connection, telnet_input, telnet_connection_closed, telnet_service);
600
601 return ERROR_OK;
602 }
603
604 int telnet_register_commands(command_context_t *command_context)
605 {
606 register_command(command_context, NULL, "exit", handle_exit_command,
607 COMMAND_EXEC, "exit telnet session");
608
609 register_command(command_context, NULL, "telnet_port", handle_telnet_port_command,
610 COMMAND_CONFIG, "");
611
612 return ERROR_OK;
613 }
614
615 /* daemon configuration command telnet_port */
616 int handle_telnet_port_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
617 {
618 if (argc == 0)
619 return ERROR_OK;
620
621 /* only if the port wasn't overwritten by cmdline */
622 if (telnet_port == 0)
623 telnet_port = strtoul(args[0], NULL, 0);
624
625 return ERROR_OK;
626 }
627
628 int handle_exit_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
629 {
630 return ERROR_COMMAND_CLOSE_CONNECTION;
631 }