xref: /freebsd/crypto/openssh/ttymodes.c (revision 23f282aa31e9b6fceacd449020e936e98d6f2298)
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  * Created: Tue Mar 21 15:59:15 1995 ylo
6  * Encoding and decoding of terminal modes in a portable way.
7  * Much of the format is defined in ttymodes.h; it is included multiple times
8  * into this file with the appropriate macro definitions to generate the
9  * suitable code.
10  */
11 
12 #include "includes.h"
13 RCSID("$Id: ttymodes.c,v 1.5 1999/11/24 19:53:54 markus Exp $");
14 
15 #include "packet.h"
16 #include "ssh.h"
17 
18 #define TTY_OP_END	0
19 #define TTY_OP_ISPEED	192	/* int follows */
20 #define TTY_OP_OSPEED	193	/* int follows */
21 
22 /*
23  * Converts POSIX speed_t to a baud rate.  The values of the
24  * constants for speed_t are not themselves portable.
25  */
26 static int
27 speed_to_baud(speed_t speed)
28 {
29 	switch (speed) {
30 	case B0:
31 		return 0;
32 	case B50:
33 		return 50;
34 	case B75:
35 		return 75;
36 	case B110:
37 		return 110;
38 	case B134:
39 		return 134;
40 	case B150:
41 		return 150;
42 	case B200:
43 		return 200;
44 	case B300:
45 		return 300;
46 	case B600:
47 		return 600;
48 	case B1200:
49 		return 1200;
50 	case B1800:
51 		return 1800;
52 	case B2400:
53 		return 2400;
54 	case B4800:
55 		return 4800;
56 	case B9600:
57 		return 9600;
58 
59 #ifdef B19200
60 	case B19200:
61 		return 19200;
62 #else /* B19200 */
63 #ifdef EXTA
64 	case EXTA:
65 		return 19200;
66 #endif /* EXTA */
67 #endif /* B19200 */
68 
69 #ifdef B38400
70 	case B38400:
71 		return 38400;
72 #else /* B38400 */
73 #ifdef EXTB
74 	case EXTB:
75 		return 38400;
76 #endif /* EXTB */
77 #endif /* B38400 */
78 
79 #ifdef B7200
80 	case B7200:
81 		return 7200;
82 #endif /* B7200 */
83 #ifdef B14400
84 	case B14400:
85 		return 14400;
86 #endif /* B14400 */
87 #ifdef B28800
88 	case B28800:
89 		return 28800;
90 #endif /* B28800 */
91 #ifdef B57600
92 	case B57600:
93 		return 57600;
94 #endif /* B57600 */
95 #ifdef B76800
96 	case B76800:
97 		return 76800;
98 #endif /* B76800 */
99 #ifdef B115200
100 	case B115200:
101 		return 115200;
102 #endif /* B115200 */
103 #ifdef B230400
104 	case B230400:
105 		return 230400;
106 #endif /* B230400 */
107 	default:
108 		return 9600;
109 	}
110 }
111 
112 /*
113  * Converts a numeric baud rate to a POSIX speed_t.
114  */
115 static speed_t
116 baud_to_speed(int baud)
117 {
118 	switch (baud) {
119 		case 0:
120 		return B0;
121 	case 50:
122 		return B50;
123 	case 75:
124 		return B75;
125 	case 110:
126 		return B110;
127 	case 134:
128 		return B134;
129 	case 150:
130 		return B150;
131 	case 200:
132 		return B200;
133 	case 300:
134 		return B300;
135 	case 600:
136 		return B600;
137 	case 1200:
138 		return B1200;
139 	case 1800:
140 		return B1800;
141 	case 2400:
142 		return B2400;
143 	case 4800:
144 		return B4800;
145 	case 9600:
146 		return B9600;
147 
148 #ifdef B19200
149 	case 19200:
150 		return B19200;
151 #else /* B19200 */
152 #ifdef EXTA
153 	case 19200:
154 		return EXTA;
155 #endif /* EXTA */
156 #endif /* B19200 */
157 
158 #ifdef B38400
159 	case 38400:
160 		return B38400;
161 #else /* B38400 */
162 #ifdef EXTB
163 	case 38400:
164 		return EXTB;
165 #endif /* EXTB */
166 #endif /* B38400 */
167 
168 #ifdef B7200
169 	case 7200:
170 		return B7200;
171 #endif /* B7200 */
172 #ifdef B14400
173 	case 14400:
174 		return B14400;
175 #endif /* B14400 */
176 #ifdef B28800
177 	case 28800:
178 		return B28800;
179 #endif /* B28800 */
180 #ifdef B57600
181 	case 57600:
182 		return B57600;
183 #endif /* B57600 */
184 #ifdef B76800
185 	case 76800:
186 		return B76800;
187 #endif /* B76800 */
188 #ifdef B115200
189 	case 115200:
190 		return B115200;
191 #endif /* B115200 */
192 #ifdef B230400
193 	case 230400:
194 		return B230400;
195 #endif /* B230400 */
196 	default:
197 		return B9600;
198 	}
199 }
200 
201 /*
202  * Encodes terminal modes for the terminal referenced by fd
203  * in a portable manner, and appends the modes to a packet
204  * being constructed.
205  */
206 void
207 tty_make_modes(int fd)
208 {
209 	struct termios tio;
210 	int baud;
211 
212 	if (tcgetattr(fd, &tio) < 0) {
213 		packet_put_char(TTY_OP_END);
214 		log("tcgetattr: %.100s", strerror(errno));
215 		return;
216 	}
217 	/* Store input and output baud rates. */
218 	baud = speed_to_baud(cfgetospeed(&tio));
219 	packet_put_char(TTY_OP_OSPEED);
220 	packet_put_int(baud);
221 	baud = speed_to_baud(cfgetispeed(&tio));
222 	packet_put_char(TTY_OP_ISPEED);
223 	packet_put_int(baud);
224 
225 	/* Store values of mode flags. */
226 #define TTYCHAR(NAME, OP) \
227   packet_put_char(OP); packet_put_char(tio.c_cc[NAME]);
228 #define TTYMODE(NAME, FIELD, OP) \
229   packet_put_char(OP); packet_put_char((tio.FIELD & NAME) != 0);
230 #define SGTTYCHAR(NAME, OP)
231 #define SGTTYMODE(NAME, FIELD, OP)
232 #define SGTTYMODEN(NAME, FIELD, OP)
233 
234 #include "ttymodes.h"
235 
236 #undef TTYCHAR
237 #undef TTYMODE
238 #undef SGTTYCHAR
239 #undef SGTTYMODE
240 #undef SGTTYMODEN
241 
242 	/* Mark end of mode data. */
243 	packet_put_char(TTY_OP_END);
244 }
245 
246 /*
247  * Decodes terminal modes for the terminal referenced by fd in a portable
248  * manner from a packet being read.
249  */
250 void
251 tty_parse_modes(int fd, int *n_bytes_ptr)
252 {
253 	struct termios tio;
254 	int opcode, baud;
255 	int n_bytes = 0;
256 	int failure = 0;
257 
258 	/*
259 	 * Get old attributes for the terminal.  We will modify these
260 	 * flags. I am hoping that if there are any machine-specific
261 	 * modes, they will initially have reasonable values.
262 	 */
263 	if (tcgetattr(fd, &tio) < 0)
264 		failure = -1;
265 
266 	for (;;) {
267 		n_bytes += 1;
268 		opcode = packet_get_char();
269 		switch (opcode) {
270 		case TTY_OP_END:
271 			goto set;
272 
273 		case TTY_OP_ISPEED:
274 			n_bytes += 4;
275 			baud = packet_get_int();
276 			if (failure != -1 && cfsetispeed(&tio, baud_to_speed(baud)) < 0)
277 				error("cfsetispeed failed for %d", baud);
278 			break;
279 
280 		case TTY_OP_OSPEED:
281 			n_bytes += 4;
282 			baud = packet_get_int();
283 			if (failure != -1 && cfsetospeed(&tio, baud_to_speed(baud)) < 0)
284 				error("cfsetospeed failed for %d", baud);
285 			break;
286 
287 #define TTYCHAR(NAME, OP) 				\
288 	case OP:					\
289 	  n_bytes += 1;					\
290 	  tio.c_cc[NAME] = packet_get_char();		\
291 	  break;
292 #define TTYMODE(NAME, FIELD, OP)		       	\
293 	case OP:					\
294 	  n_bytes += 1;					\
295 	  if (packet_get_char())			\
296 	    tio.FIELD |= NAME;				\
297 	  else						\
298 	    tio.FIELD &= ~NAME;				\
299 	  break;
300 #define SGTTYCHAR(NAME, OP)
301 #define SGTTYMODE(NAME, FIELD, OP)
302 #define SGTTYMODEN(NAME, FIELD, OP)
303 
304 #include "ttymodes.h"
305 
306 #undef TTYCHAR
307 #undef TTYMODE
308 #undef SGTTYCHAR
309 #undef SGTTYMODE
310 #undef SGTTYMODEN
311 
312 		default:
313 			debug("Ignoring unsupported tty mode opcode %d (0x%x)",
314 			      opcode, opcode);
315 			/*
316 			 * Opcodes 0 to 127 are defined to have
317 			 * a one-byte argument.
318 			 */
319 			if (opcode >= 0 && opcode < 128) {
320 				n_bytes += 1;
321 				(void) packet_get_char();
322 				break;
323 			} else {
324 				/*
325 				 * Opcodes 128 to 159 are defined to have
326 				 * an integer argument.
327 				 */
328 				if (opcode >= 128 && opcode < 160) {
329 					n_bytes += 4;
330 					(void) packet_get_int();
331 					break;
332 				}
333 			}
334 			/*
335 			 * It is a truly undefined opcode (160 to 255).
336 			 * We have no idea about its arguments.  So we
337 			 * must stop parsing.  Note that some data may be
338 			 * left in the packet; hopefully there is nothing
339 			 * more coming after the mode data.
340 			 */
341 			log("parse_tty_modes: unknown opcode %d", opcode);
342 			packet_integrity_check(0, 1, SSH_CMSG_REQUEST_PTY);
343 			goto set;
344 		}
345 	}
346 
347 set:
348 	if (*n_bytes_ptr != n_bytes) {
349 		*n_bytes_ptr = n_bytes;
350 		return;		/* Don't process bytes passed */
351 	}
352 	if (failure == -1)
353 		return;		/* Packet parsed ok but tty stuff failed */
354 
355 	/* Set the new modes for the terminal. */
356 	if (tcsetattr(fd, TCSANOW, &tio) < 0)
357 		log("Setting tty modes failed: %.100s", strerror(errno));
358 	return;
359 }
360