xref: /titanic_50/usr/src/cmd/ssh/libssh/common/ttymodes.c (revision ba7866cd2cbdf574f47d4e38a1301b90744dd677)
1 /*
2  * Author: Tatu Ylonen <ylo@cs.hut.fi>
3  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
4  *                    All rights reserved
5  *
6  * As far as I am concerned, the code I have written for this software
7  * can be used freely for any purpose.  Any derived versions of this
8  * software must be clearly marked as such, and if the derived work is
9  * incompatible with the protocol description in the RFC file, it must be
10  * called by a name other than "ssh" or "Secure Shell".
11  */
12 
13 /*
14  * SSH2 tty modes support by Kevin Steves.
15  * Copyright (c) 2001 Kevin Steves.  All rights reserved.
16  *
17  * Redistribution and use in source and binary forms, with or without
18  * modification, are permitted provided that the following conditions
19  * are met:
20  * 1. Redistributions of source code must retain the above copyright
21  *    notice, this list of conditions and the following disclaimer.
22  * 2. Redistributions in binary form must reproduce the above copyright
23  *    notice, this list of conditions and the following disclaimer in the
24  *    documentation and/or other materials provided with the distribution.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
27  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
28  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
29  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
30  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
31  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
32  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
33  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
34  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
35  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
36  */
37 
38 /*
39  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
40  * Use is subject to license terms.
41  */
42 
43 /*
44  * Encoding and decoding of terminal modes in a portable way.
45  * Much of the format is defined in ttymodes.h; it is included multiple times
46  * into this file with the appropriate macro definitions to generate the
47  * suitable code.
48  */
49 
50 #include "includes.h"
51 RCSID("$OpenBSD: ttymodes.c,v 1.18 2002/06/19 00:27:55 deraadt Exp $");
52 
53 #include "packet.h"
54 #include "log.h"
55 #include "ssh1.h"
56 #include "compat.h"
57 #include "buffer.h"
58 #include "bufaux.h"
59 
60 #define TTY_OP_END		0
61 /*
62  * uint32 (u_int) follows speed in SSH1 and SSH2
63  */
64 #define TTY_OP_ISPEED_PROTO1	192
65 #define TTY_OP_OSPEED_PROTO1	193
66 #define TTY_OP_ISPEED_PROTO2	128
67 #define TTY_OP_OSPEED_PROTO2	129
68 
69 /*
70  * Converts POSIX speed_t to a baud rate.  The values of the
71  * constants for speed_t are not themselves portable.
72  */
73 static int
74 speed_to_baud(speed_t speed)
75 {
76 	switch (speed) {
77 	case B0:
78 		return 0;
79 	case B50:
80 		return 50;
81 	case B75:
82 		return 75;
83 	case B110:
84 		return 110;
85 	case B134:
86 		return 134;
87 	case B150:
88 		return 150;
89 	case B200:
90 		return 200;
91 	case B300:
92 		return 300;
93 	case B600:
94 		return 600;
95 	case B1200:
96 		return 1200;
97 	case B1800:
98 		return 1800;
99 	case B2400:
100 		return 2400;
101 	case B4800:
102 		return 4800;
103 	case B9600:
104 		return 9600;
105 
106 #ifdef B19200
107 	case B19200:
108 		return 19200;
109 #else /* B19200 */
110 #ifdef EXTA
111 	case EXTA:
112 		return 19200;
113 #endif /* EXTA */
114 #endif /* B19200 */
115 
116 #ifdef B38400
117 	case B38400:
118 		return 38400;
119 #else /* B38400 */
120 #ifdef EXTB
121 	case EXTB:
122 		return 38400;
123 #endif /* EXTB */
124 #endif /* B38400 */
125 
126 #ifdef B7200
127 	case B7200:
128 		return 7200;
129 #endif /* B7200 */
130 #ifdef B14400
131 	case B14400:
132 		return 14400;
133 #endif /* B14400 */
134 #ifdef B28800
135 	case B28800:
136 		return 28800;
137 #endif /* B28800 */
138 #ifdef B57600
139 	case B57600:
140 		return 57600;
141 #endif /* B57600 */
142 #ifdef B76800
143 	case B76800:
144 		return 76800;
145 #endif /* B76800 */
146 #ifdef B115200
147 	case B115200:
148 		return 115200;
149 #endif /* B115200 */
150 #ifdef B230400
151 	case B230400:
152 		return 230400;
153 #endif /* B230400 */
154 #ifdef B460800
155 	case B460800:
156 		return 460800;
157 #endif /* B460800 */
158 #ifdef B921600
159 	case B921600:
160 		return 921600;
161 #endif /* B921600 */
162 	default:
163 		return 9600;
164 	}
165 }
166 
167 /*
168  * Converts a numeric baud rate to a POSIX speed_t.
169  */
170 static speed_t
171 baud_to_speed(int baud)
172 {
173 	switch (baud) {
174 	case 0:
175 		return B0;
176 	case 50:
177 		return B50;
178 	case 75:
179 		return B75;
180 	case 110:
181 		return B110;
182 	case 134:
183 		return B134;
184 	case 150:
185 		return B150;
186 	case 200:
187 		return B200;
188 	case 300:
189 		return B300;
190 	case 600:
191 		return B600;
192 	case 1200:
193 		return B1200;
194 	case 1800:
195 		return B1800;
196 	case 2400:
197 		return B2400;
198 	case 4800:
199 		return B4800;
200 	case 9600:
201 		return B9600;
202 
203 #ifdef B19200
204 	case 19200:
205 		return B19200;
206 #else /* B19200 */
207 #ifdef EXTA
208 	case 19200:
209 		return EXTA;
210 #endif /* EXTA */
211 #endif /* B19200 */
212 
213 #ifdef B38400
214 	case 38400:
215 		return B38400;
216 #else /* B38400 */
217 #ifdef EXTB
218 	case 38400:
219 		return EXTB;
220 #endif /* EXTB */
221 #endif /* B38400 */
222 
223 #ifdef B7200
224 	case 7200:
225 		return B7200;
226 #endif /* B7200 */
227 #ifdef B14400
228 	case 14400:
229 		return B14400;
230 #endif /* B14400 */
231 #ifdef B28800
232 	case 28800:
233 		return B28800;
234 #endif /* B28800 */
235 #ifdef B57600
236 	case 57600:
237 		return B57600;
238 #endif /* B57600 */
239 #ifdef B76800
240 	case 76800:
241 		return B76800;
242 #endif /* B76800 */
243 #ifdef B115200
244 	case 115200:
245 		return B115200;
246 #endif /* B115200 */
247 #ifdef B230400
248 	case 230400:
249 		return B230400;
250 #endif /* B230400 */
251 #ifdef B460800
252 	case 460800:
253 		return B460800;
254 #endif /* B460800 */
255 #ifdef B921600
256 	case 921600:
257 		return B921600;
258 #endif /* B921600 */
259 	default:
260 		return B9600;
261 	}
262 }
263 
264 /*
265  * Encodes terminal modes for the terminal referenced by fd
266  * or tiop in a portable manner, and appends the modes to a packet
267  * being constructed.
268  */
269 void
270 tty_make_modes(int fd, struct termios *tiop)
271 {
272 	struct termios tio;
273 	int baud;
274 	Buffer buf;
275 	int tty_op_ospeed, tty_op_ispeed;
276 	void (*put_arg)(Buffer *, u_int);
277 
278 	buffer_init(&buf);
279 	if (compat20) {
280 		tty_op_ospeed = TTY_OP_OSPEED_PROTO2;
281 		tty_op_ispeed = TTY_OP_ISPEED_PROTO2;
282 		put_arg = buffer_put_int;
283 	} else {
284 		tty_op_ospeed = TTY_OP_OSPEED_PROTO1;
285 		tty_op_ispeed = TTY_OP_ISPEED_PROTO1;
286 		put_arg = (void (*)(Buffer *, u_int)) buffer_put_char;
287 	}
288 
289 	if (tiop == NULL) {
290 		if (tcgetattr(fd, &tio) == -1) {
291 			log("tcgetattr: %.100s", strerror(errno));
292 			goto end;
293 		}
294 	} else
295 		tio = *tiop;
296 
297 	/* Store input and output baud rates. */
298 	baud = speed_to_baud(cfgetospeed(&tio));
299 	debug3("tty_make_modes: ospeed %d", baud);
300 	buffer_put_char(&buf, tty_op_ospeed);
301 	buffer_put_int(&buf, baud);
302 	baud = speed_to_baud(cfgetispeed(&tio));
303 	debug3("tty_make_modes: ispeed %d", baud);
304 	buffer_put_char(&buf, tty_op_ispeed);
305 	buffer_put_int(&buf, baud);
306 
307 	/* Store values of mode flags. */
308 #define TTYCHAR(NAME, OP) \
309 	debug3("tty_make_modes: %d %d", OP, tio.c_cc[NAME]); \
310 	buffer_put_char(&buf, OP); \
311 	put_arg(&buf, tio.c_cc[NAME]);
312 
313 #define TTYMODE(NAME, FIELD, OP) \
314 	debug3("tty_make_modes: %d %d", OP, ((tio.FIELD & NAME) != 0)); \
315 	buffer_put_char(&buf, OP); \
316 	put_arg(&buf, ((tio.FIELD & NAME) != 0));
317 
318 #include "ttymodes.h"
319 
320 #undef TTYCHAR
321 #undef TTYMODE
322 
323 end:
324 	/* Mark end of mode data. */
325 	buffer_put_char(&buf, TTY_OP_END);
326 	if (compat20)
327 		packet_put_string(buffer_ptr(&buf), buffer_len(&buf));
328 	else
329 		packet_put_raw(buffer_ptr(&buf), buffer_len(&buf));
330 	buffer_free(&buf);
331 }
332 
333 /*
334  * Decodes terminal modes for the terminal referenced by fd in a portable
335  * manner from a packet being read.
336  */
337 void
338 tty_parse_modes(int fd, int *n_bytes_ptr)
339 {
340 	struct termios tio;
341 	int opcode, baud;
342 	int n_bytes = 0;
343 	int failure = 0;
344 	u_int (*get_arg)(void);
345 	int arg, arg_size;
346 
347 	if (compat20) {
348 		*n_bytes_ptr = packet_get_int();
349 		debug3("tty_parse_modes: SSH2 n_bytes %d", *n_bytes_ptr);
350 		if (*n_bytes_ptr == 0)
351 			return;
352 		get_arg = packet_get_int;
353 		arg_size = 4;
354 	} else {
355 		get_arg = packet_get_char;
356 		arg_size = 1;
357 	}
358 
359 	/*
360 	 * Get old attributes for the terminal.  We will modify these
361 	 * flags. I am hoping that if there are any machine-specific
362 	 * modes, they will initially have reasonable values.
363 	 */
364 	if (tcgetattr(fd, &tio) == -1) {
365 		log("tcgetattr: %.100s", strerror(errno));
366 		failure = -1;
367 	}
368 
369 	for (;;) {
370 		n_bytes += 1;
371 		opcode = packet_get_char();
372 		switch (opcode) {
373 		case TTY_OP_END:
374 			goto set;
375 
376 		/* XXX: future conflict possible */
377 		case TTY_OP_ISPEED_PROTO1:
378 		case TTY_OP_ISPEED_PROTO2:
379 			n_bytes += 4;
380 			baud = packet_get_int();
381 			debug3("tty_parse_modes: ispeed %d", baud);
382 			if (failure != -1 && cfsetispeed(&tio, baud_to_speed(baud)) == -1)
383 				error("cfsetispeed failed for %d", baud);
384 			break;
385 
386 		/* XXX: future conflict possible */
387 		case TTY_OP_OSPEED_PROTO1:
388 		case TTY_OP_OSPEED_PROTO2:
389 			n_bytes += 4;
390 			baud = packet_get_int();
391 			debug3("tty_parse_modes: ospeed %d", baud);
392 			if (failure != -1 && cfsetospeed(&tio, baud_to_speed(baud)) == -1)
393 				error("cfsetospeed failed for %d", baud);
394 			break;
395 
396 #define TTYCHAR(NAME, OP) \
397 	case OP: \
398 	  n_bytes += arg_size; \
399 	  tio.c_cc[NAME] = get_arg(); \
400 	  debug3("tty_parse_modes: %d %d", OP, tio.c_cc[NAME]); \
401 	  break;
402 #define TTYMODE(NAME, FIELD, OP) \
403 	case OP: \
404 	  n_bytes += arg_size; \
405 	  if ((arg = get_arg())) \
406 	    tio.FIELD |= NAME; \
407 	  else \
408 	    tio.FIELD &= ~NAME;	\
409 	  debug3("tty_parse_modes: %d %d", OP, arg); \
410 	  break;
411 
412 #include "ttymodes.h"
413 
414 #undef TTYCHAR
415 #undef TTYMODE
416 
417 		default:
418 			debug("Ignoring unsupported tty mode opcode %d (0x%x)",
419 			    opcode, opcode);
420 			if (!compat20) {
421 				/*
422 				 * SSH1:
423 				 * Opcodes 1 to 127 are defined to have
424 				 * a one-byte argument.
425 				 * Opcodes 128 to 159 are defined to have
426 				 * an integer argument.
427 				 */
428 				if (opcode > 0 && opcode < 128) {
429 					n_bytes += 1;
430 					(void) packet_get_char();
431 					break;
432 				} else if (opcode >= 128 && opcode < 160) {
433 					n_bytes += 4;
434 					(void) packet_get_int();
435 					break;
436 				} else {
437 					/*
438 					 * It is a truly undefined opcode (160 to 255).
439 					 * We have no idea about its arguments.  So we
440 					 * must stop parsing.  Note that some data may be
441 					 * left in the packet; hopefully there is nothing
442 					 * more coming after the mode data.
443 					 */
444 					log("parse_tty_modes: unknown opcode %d", opcode);
445 					goto set;
446 				}
447 			} else {
448 				/*
449 				 * SSH2:
450 				 * Opcodes 1 to 159 are defined to have
451 				 * a uint32 argument.
452 				 * Opcodes 160 to 255 are undefined and
453 				 * cause parsing to stop.
454 				 */
455 				if (opcode > 0 && opcode < 160) {
456 					n_bytes += 4;
457 					(void) packet_get_int();
458 					break;
459 				} else {
460 					log("parse_tty_modes: unknown opcode %d", opcode);
461 					goto set;
462 				}
463 			}
464 		}
465 	}
466 
467 set:
468 	if (*n_bytes_ptr != n_bytes) {
469 		*n_bytes_ptr = n_bytes;
470 		log("parse_tty_modes: n_bytes_ptr != n_bytes: %d %d",
471 		    *n_bytes_ptr, n_bytes);
472 		return;		/* Don't process bytes passed */
473 	}
474 	if (failure == -1)
475 		return;		/* Packet parsed ok but tcgetattr() failed */
476 
477 	/* Set the new modes for the terminal. */
478 	if (tcsetattr(fd, TCSANOW, &tio) == -1)
479 		log("Setting tty modes failed: %.100s", strerror(errno));
480 }
481