aef05b78 |
1 | /* |
2 | * Serial back end (Unix-specific). |
3 | */ |
4 | |
aef05b78 |
5 | #include <stdio.h> |
6 | #include <stdlib.h> |
7 | #include <assert.h> |
8 | #include <limits.h> |
9 | |
10 | #include <errno.h> |
11 | #include <unistd.h> |
12 | #include <fcntl.h> |
13 | #include <termios.h> |
14 | |
15 | #include "putty.h" |
16 | #include "tree234.h" |
17 | |
18 | #define SERIAL_MAX_BACKLOG 4096 |
19 | |
20 | typedef struct serial_backend_data { |
21 | void *frontend; |
22 | int fd; |
23 | int finished; |
24 | int inbufsize; |
25 | bufchain output_data; |
26 | } *Serial; |
27 | |
28 | /* |
29 | * We store our serial backends in a tree sorted by fd, so that |
30 | * when we get an uxsel notification we know which backend instance |
31 | * is the owner of the serial port that caused it. |
32 | */ |
33 | static int serial_compare_by_fd(void *av, void *bv) |
34 | { |
35 | Serial a = (Serial)av; |
36 | Serial b = (Serial)bv; |
37 | |
38 | if (a->fd < b->fd) |
39 | return -1; |
40 | else if (a->fd > b->fd) |
41 | return +1; |
42 | return 0; |
43 | } |
44 | |
45 | static int serial_find_by_fd(void *av, void *bv) |
46 | { |
47 | int a = *(int *)av; |
48 | Serial b = (Serial)bv; |
49 | |
50 | if (a < b->fd) |
51 | return -1; |
52 | else if (a > b->fd) |
53 | return +1; |
54 | return 0; |
55 | } |
56 | |
57 | static tree234 *serial_by_fd = NULL; |
58 | |
59 | static int serial_select_result(int fd, int event); |
60 | static void serial_uxsel_setup(Serial serial); |
61 | static void serial_try_write(Serial serial); |
62 | |
4a693cfc |
63 | static const char *serial_configure(Serial serial, Conf *conf) |
aef05b78 |
64 | { |
65 | struct termios options; |
4a693cfc |
66 | int bflag, bval, speed, flow, parity; |
aef05b78 |
67 | const char *str; |
68 | char *msg; |
69 | |
70 | if (serial->fd < 0) |
71 | return "Unable to reconfigure already-closed serial connection"; |
72 | |
73 | tcgetattr(serial->fd, &options); |
74 | |
75 | /* |
76 | * Find the appropriate baud rate flag. |
77 | */ |
4a693cfc |
78 | speed = conf_get_int(conf, CONF_serspeed); |
aef05b78 |
79 | #define SETBAUD(x) (bflag = B ## x, bval = x) |
4a693cfc |
80 | #define CHECKBAUD(x) do { if (speed >= x) SETBAUD(x); } while (0) |
aef05b78 |
81 | SETBAUD(50); |
82 | #ifdef B75 |
83 | CHECKBAUD(75); |
84 | #endif |
85 | #ifdef B110 |
86 | CHECKBAUD(110); |
87 | #endif |
88 | #ifdef B134 |
89 | CHECKBAUD(134); |
90 | #endif |
91 | #ifdef B150 |
92 | CHECKBAUD(150); |
93 | #endif |
94 | #ifdef B200 |
95 | CHECKBAUD(200); |
96 | #endif |
97 | #ifdef B300 |
98 | CHECKBAUD(300); |
99 | #endif |
100 | #ifdef B600 |
101 | CHECKBAUD(600); |
102 | #endif |
103 | #ifdef B1200 |
104 | CHECKBAUD(1200); |
105 | #endif |
106 | #ifdef B1800 |
107 | CHECKBAUD(1800); |
108 | #endif |
109 | #ifdef B2400 |
110 | CHECKBAUD(2400); |
111 | #endif |
112 | #ifdef B4800 |
113 | CHECKBAUD(4800); |
114 | #endif |
115 | #ifdef B9600 |
116 | CHECKBAUD(9600); |
117 | #endif |
118 | #ifdef B19200 |
119 | CHECKBAUD(19200); |
120 | #endif |
121 | #ifdef B38400 |
122 | CHECKBAUD(38400); |
123 | #endif |
124 | #ifdef B57600 |
125 | CHECKBAUD(57600); |
126 | #endif |
127 | #ifdef B76800 |
128 | CHECKBAUD(76800); |
129 | #endif |
130 | #ifdef B115200 |
131 | CHECKBAUD(115200); |
132 | #endif |
25d0ab1e |
133 | #ifdef B153600 |
134 | CHECKBAUD(153600); |
135 | #endif |
aef05b78 |
136 | #ifdef B230400 |
137 | CHECKBAUD(230400); |
138 | #endif |
25d0ab1e |
139 | #ifdef B307200 |
140 | CHECKBAUD(307200); |
141 | #endif |
142 | #ifdef B460800 |
143 | CHECKBAUD(460800); |
144 | #endif |
145 | #ifdef B500000 |
146 | CHECKBAUD(500000); |
147 | #endif |
148 | #ifdef B576000 |
149 | CHECKBAUD(576000); |
150 | #endif |
151 | #ifdef B921600 |
152 | CHECKBAUD(921600); |
153 | #endif |
154 | #ifdef B1000000 |
155 | CHECKBAUD(1000000); |
156 | #endif |
157 | #ifdef B1152000 |
158 | CHECKBAUD(1152000); |
159 | #endif |
160 | #ifdef B1500000 |
161 | CHECKBAUD(1500000); |
162 | #endif |
163 | #ifdef B2000000 |
164 | CHECKBAUD(2000000); |
165 | #endif |
166 | #ifdef B2500000 |
167 | CHECKBAUD(2500000); |
168 | #endif |
169 | #ifdef B3000000 |
170 | CHECKBAUD(3000000); |
171 | #endif |
172 | #ifdef B3500000 |
173 | CHECKBAUD(3500000); |
174 | #endif |
175 | #ifdef B4000000 |
176 | CHECKBAUD(4000000); |
177 | #endif |
aef05b78 |
178 | #undef CHECKBAUD |
179 | #undef SETBAUD |
180 | cfsetispeed(&options, bflag); |
181 | cfsetospeed(&options, bflag); |
182 | msg = dupprintf("Configuring baud rate %d", bval); |
183 | logevent(serial->frontend, msg); |
184 | sfree(msg); |
185 | |
186 | options.c_cflag &= ~CSIZE; |
4a693cfc |
187 | switch (conf_get_int(conf, CONF_serdatabits)) { |
aef05b78 |
188 | case 5: options.c_cflag |= CS5; break; |
189 | case 6: options.c_cflag |= CS6; break; |
190 | case 7: options.c_cflag |= CS7; break; |
191 | case 8: options.c_cflag |= CS8; break; |
192 | default: return "Invalid number of data bits (need 5, 6, 7 or 8)"; |
193 | } |
4a693cfc |
194 | msg = dupprintf("Configuring %d data bits", |
195 | conf_get_int(conf, CONF_serdatabits)); |
aef05b78 |
196 | logevent(serial->frontend, msg); |
197 | sfree(msg); |
198 | |
4a693cfc |
199 | if (conf_get_int(conf, CONF_serstopbits) >= 4) { |
aef05b78 |
200 | options.c_cflag |= CSTOPB; |
201 | } else { |
202 | options.c_cflag &= ~CSTOPB; |
203 | } |
204 | msg = dupprintf("Configuring %d stop bits", |
205 | (options.c_cflag & CSTOPB ? 2 : 1)); |
206 | logevent(serial->frontend, msg); |
207 | sfree(msg); |
208 | |
e26f8aa1 |
209 | options.c_iflag &= ~(IXON|IXOFF); |
210 | #ifdef CRTSCTS |
211 | options.c_cflag &= ~CRTSCTS; |
212 | #endif |
213 | #ifdef CNEW_RTSCTS |
214 | options.c_cflag &= ~CNEW_RTSCTS; |
215 | #endif |
4a693cfc |
216 | flow = conf_get_int(conf, CONF_serflow); |
217 | if (flow == SER_FLOW_XONXOFF) { |
e26f8aa1 |
218 | options.c_iflag |= IXON | IXOFF; |
aef05b78 |
219 | str = "XON/XOFF"; |
4a693cfc |
220 | } else if (flow == SER_FLOW_RTSCTS) { |
aef05b78 |
221 | #ifdef CRTSCTS |
222 | options.c_cflag |= CRTSCTS; |
223 | #endif |
224 | #ifdef CNEW_RTSCTS |
225 | options.c_cflag |= CNEW_RTSCTS; |
226 | #endif |
227 | str = "RTS/CTS"; |
228 | } else |
229 | str = "no"; |
230 | msg = dupprintf("Configuring %s flow control", str); |
231 | logevent(serial->frontend, msg); |
232 | sfree(msg); |
233 | |
234 | /* Parity */ |
4a693cfc |
235 | parity = conf_get_int(conf, CONF_serparity); |
236 | if (parity == SER_PAR_ODD) { |
aef05b78 |
237 | options.c_cflag |= PARENB; |
238 | options.c_cflag |= PARODD; |
239 | str = "odd"; |
4a693cfc |
240 | } else if (parity == SER_PAR_EVEN) { |
aef05b78 |
241 | options.c_cflag |= PARENB; |
242 | options.c_cflag &= ~PARODD; |
243 | str = "even"; |
244 | } else { |
245 | options.c_cflag &= ~PARENB; |
246 | str = "no"; |
247 | } |
248 | msg = dupprintf("Configuring %s parity", str); |
249 | logevent(serial->frontend, msg); |
250 | sfree(msg); |
251 | |
252 | options.c_cflag |= CLOCAL | CREAD; |
253 | options.c_lflag &= ~(ICANON | ECHO | ECHOE | ISIG); |
9a41f8d3 |
254 | options.c_iflag &= ~(ISTRIP | IGNCR | INLCR | ICRNL |
255 | #ifdef IUCLC |
256 | | IUCLC |
257 | #endif |
258 | ); |
259 | options.c_oflag &= ~(OPOST |
260 | #ifdef ONLCR |
261 | | ONLCR |
262 | #endif |
e8c03e4c |
263 | #ifdef OCRNL |
264 | | OCRNL |
265 | #endif |
266 | #ifdef ONOCR |
267 | | ONOCR |
268 | #endif |
269 | #ifdef ONLRET |
270 | | ONLRET |
271 | #endif |
272 | ); |
aef05b78 |
273 | options.c_cc[VMIN] = 1; |
274 | options.c_cc[VTIME] = 0; |
275 | |
276 | if (tcsetattr(serial->fd, TCSANOW, &options) < 0) |
277 | return "Unable to configure serial port"; |
278 | |
279 | return NULL; |
280 | } |
281 | |
282 | /* |
283 | * Called to set up the serial connection. |
284 | * |
285 | * Returns an error message, or NULL on success. |
286 | * |
287 | * Also places the canonical host name into `realhost'. It must be |
288 | * freed by the caller. |
289 | */ |
290 | static const char *serial_init(void *frontend_handle, void **backend_handle, |
4a693cfc |
291 | Conf *conf, |
aef05b78 |
292 | char *host, int port, char **realhost, int nodelay, |
293 | int keepalive) |
294 | { |
295 | Serial serial; |
296 | const char *err; |
4a693cfc |
297 | char *line; |
aef05b78 |
298 | |
299 | serial = snew(struct serial_backend_data); |
300 | *backend_handle = serial; |
301 | |
302 | serial->frontend = frontend_handle; |
303 | serial->finished = FALSE; |
304 | serial->inbufsize = 0; |
305 | bufchain_init(&serial->output_data); |
306 | |
4a693cfc |
307 | line = conf_get_str(conf, CONF_serline); |
aef05b78 |
308 | { |
4a693cfc |
309 | char *msg = dupprintf("Opening serial device %s", line); |
aef05b78 |
310 | logevent(serial->frontend, msg); |
311 | } |
312 | |
4a693cfc |
313 | serial->fd = open(line, O_RDWR | O_NOCTTY | O_NDELAY | O_NONBLOCK); |
aef05b78 |
314 | if (serial->fd < 0) |
315 | return "Unable to open serial port"; |
316 | |
db9b7dce |
317 | cloexec(serial->fd); |
89e97516 |
318 | |
4a693cfc |
319 | err = serial_configure(serial, conf); |
aef05b78 |
320 | if (err) |
321 | return err; |
322 | |
4a693cfc |
323 | *realhost = dupstr(line); |
aef05b78 |
324 | |
325 | if (!serial_by_fd) |
326 | serial_by_fd = newtree234(serial_compare_by_fd); |
327 | add234(serial_by_fd, serial); |
328 | |
329 | serial_uxsel_setup(serial); |
330 | |
45ef7ce3 |
331 | /* |
332 | * Specials are always available. |
333 | */ |
334 | update_specials_menu(serial->frontend); |
335 | |
aef05b78 |
336 | return NULL; |
337 | } |
338 | |
339 | static void serial_close(Serial serial) |
340 | { |
341 | if (serial->fd >= 0) { |
342 | close(serial->fd); |
343 | serial->fd = -1; |
344 | } |
345 | } |
346 | |
347 | static void serial_free(void *handle) |
348 | { |
349 | Serial serial = (Serial) handle; |
350 | |
351 | serial_close(serial); |
352 | |
353 | bufchain_clear(&serial->output_data); |
354 | |
355 | sfree(serial); |
356 | } |
357 | |
4a693cfc |
358 | static void serial_reconfig(void *handle, Conf *conf) |
aef05b78 |
359 | { |
360 | Serial serial = (Serial) handle; |
aef05b78 |
361 | |
362 | /* |
3ab79841 |
363 | * FIXME: what should we do if this returns an error? |
aef05b78 |
364 | */ |
4a693cfc |
365 | serial_configure(serial, conf); |
aef05b78 |
366 | } |
367 | |
368 | static int serial_select_result(int fd, int event) |
369 | { |
370 | Serial serial; |
371 | char buf[4096]; |
372 | int ret; |
373 | int finished = FALSE; |
374 | |
375 | serial = find234(serial_by_fd, &fd, serial_find_by_fd); |
376 | |
377 | if (!serial) |
378 | return 1; /* spurious event; keep going */ |
379 | |
380 | if (event == 1) { |
381 | ret = read(serial->fd, buf, sizeof(buf)); |
382 | |
383 | if (ret == 0) { |
384 | /* |
385 | * Shouldn't happen on a real serial port, but I'm open |
386 | * to the idea that there might be two-way devices we |
387 | * can treat _like_ serial ports which can return EOF. |
388 | */ |
389 | finished = TRUE; |
390 | } else if (ret < 0) { |
0620c88a |
391 | #ifdef EAGAIN |
392 | if (errno == EAGAIN) |
393 | return 1; /* spurious */ |
394 | #endif |
395 | #ifdef EWOULDBLOCK |
396 | if (errno == EWOULDBLOCK) |
397 | return 1; /* spurious */ |
398 | #endif |
aef05b78 |
399 | perror("read serial port"); |
400 | exit(1); |
401 | } else if (ret > 0) { |
402 | serial->inbufsize = from_backend(serial->frontend, 0, buf, ret); |
403 | serial_uxsel_setup(serial); /* might acquire backlog and freeze */ |
404 | } |
405 | } else if (event == 2) { |
406 | /* |
407 | * Attempt to send data down the pty. |
408 | */ |
409 | serial_try_write(serial); |
410 | } |
411 | |
412 | if (finished) { |
413 | serial_close(serial); |
414 | |
415 | serial->finished = TRUE; |
416 | |
417 | notify_remote_exit(serial->frontend); |
418 | } |
419 | |
420 | return !finished; |
421 | } |
422 | |
423 | static void serial_uxsel_setup(Serial serial) |
424 | { |
425 | int rwx = 0; |
426 | |
427 | if (serial->inbufsize <= SERIAL_MAX_BACKLOG) |
428 | rwx |= 1; |
429 | if (bufchain_size(&serial->output_data)) |
430 | rwx |= 2; /* might also want to write to it */ |
431 | uxsel_set(serial->fd, rwx, serial_select_result); |
432 | } |
433 | |
434 | static void serial_try_write(Serial serial) |
435 | { |
436 | void *data; |
437 | int len, ret; |
438 | |
439 | assert(serial->fd >= 0); |
440 | |
441 | while (bufchain_size(&serial->output_data) > 0) { |
442 | bufchain_prefix(&serial->output_data, &data, &len); |
443 | ret = write(serial->fd, data, len); |
444 | |
445 | if (ret < 0 && (errno == EWOULDBLOCK)) { |
446 | /* |
447 | * We've sent all we can for the moment. |
448 | */ |
449 | break; |
450 | } |
451 | if (ret < 0) { |
452 | perror("write serial port"); |
453 | exit(1); |
454 | } |
455 | bufchain_consume(&serial->output_data, ret); |
456 | } |
457 | |
458 | serial_uxsel_setup(serial); |
459 | } |
460 | |
461 | /* |
462 | * Called to send data down the serial connection. |
463 | */ |
464 | static int serial_send(void *handle, char *buf, int len) |
465 | { |
466 | Serial serial = (Serial) handle; |
467 | |
468 | if (serial->fd < 0) |
469 | return 0; |
470 | |
471 | bufchain_add(&serial->output_data, buf, len); |
472 | serial_try_write(serial); |
473 | |
474 | return bufchain_size(&serial->output_data); |
475 | } |
476 | |
477 | /* |
478 | * Called to query the current sendability status. |
479 | */ |
480 | static int serial_sendbuffer(void *handle) |
481 | { |
482 | Serial serial = (Serial) handle; |
483 | return bufchain_size(&serial->output_data); |
484 | } |
485 | |
486 | /* |
487 | * Called to set the size of the window |
488 | */ |
489 | static void serial_size(void *handle, int width, int height) |
490 | { |
491 | /* Do nothing! */ |
492 | return; |
493 | } |
494 | |
495 | /* |
496 | * Send serial special codes. |
497 | */ |
498 | static void serial_special(void *handle, Telnet_Special code) |
499 | { |
45ef7ce3 |
500 | Serial serial = (Serial) handle; |
501 | |
502 | if (serial->fd >= 0 && code == TS_BRK) { |
503 | tcsendbreak(serial->fd, 0); |
504 | logevent(serial->frontend, "Sending serial break at user request"); |
505 | } |
506 | |
aef05b78 |
507 | return; |
508 | } |
509 | |
510 | /* |
511 | * Return a list of the special codes that make sense in this |
512 | * protocol. |
513 | */ |
514 | static const struct telnet_special *serial_get_specials(void *handle) |
515 | { |
45ef7ce3 |
516 | static const struct telnet_special specials[] = { |
517 | {"Break", TS_BRK}, |
518 | {NULL, TS_EXITMENU} |
519 | }; |
520 | return specials; |
aef05b78 |
521 | } |
522 | |
523 | static int serial_connected(void *handle) |
524 | { |
525 | return 1; /* always connected */ |
526 | } |
527 | |
528 | static int serial_sendok(void *handle) |
529 | { |
530 | return 1; |
531 | } |
532 | |
533 | static void serial_unthrottle(void *handle, int backlog) |
534 | { |
535 | Serial serial = (Serial) handle; |
536 | serial->inbufsize = backlog; |
537 | serial_uxsel_setup(serial); |
538 | } |
539 | |
540 | static int serial_ldisc(void *handle, int option) |
541 | { |
542 | /* |
543 | * Local editing and local echo are off by default. |
544 | */ |
545 | return 0; |
546 | } |
547 | |
548 | static void serial_provide_ldisc(void *handle, void *ldisc) |
549 | { |
550 | /* This is a stub. */ |
551 | } |
552 | |
553 | static void serial_provide_logctx(void *handle, void *logctx) |
554 | { |
555 | /* This is a stub. */ |
556 | } |
557 | |
558 | static int serial_exitcode(void *handle) |
559 | { |
560 | Serial serial = (Serial) handle; |
561 | if (serial->fd >= 0) |
562 | return -1; /* still connected */ |
563 | else |
564 | /* Exit codes are a meaningless concept with serial ports */ |
565 | return INT_MAX; |
566 | } |
567 | |
568 | /* |
569 | * cfg_info for Serial does nothing at all. |
570 | */ |
571 | static int serial_cfg_info(void *handle) |
572 | { |
573 | return 0; |
574 | } |
575 | |
576 | Backend serial_backend = { |
577 | serial_init, |
578 | serial_free, |
579 | serial_reconfig, |
580 | serial_send, |
581 | serial_sendbuffer, |
582 | serial_size, |
583 | serial_special, |
584 | serial_get_specials, |
585 | serial_connected, |
586 | serial_exitcode, |
587 | serial_sendok, |
588 | serial_ldisc, |
589 | serial_provide_ldisc, |
590 | serial_provide_logctx, |
591 | serial_unthrottle, |
592 | serial_cfg_info, |
9e164d82 |
593 | "serial", |
594 | PROT_SERIAL, |
a4451dd1 |
595 | 0 |
aef05b78 |
596 | }; |