1 /* $OpenBSD: ttymodes.c,v 1.36 2021/01/27 09:26:54 djm Exp $ */
3 * Author: Tatu Ylonen <ylo@cs.hut.fi>
4 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
7 * As far as I am concerned, the code I have written for this software
8 * can be used freely for any purpose. Any derived versions of this
9 * software must be clearly marked as such, and if the derived work is
10 * incompatible with the protocol description in the RFC file, it must be
11 * called by a name other than "ssh" or "Secure Shell".
15 * SSH2 tty modes support by Kevin Steves.
16 * Copyright (c) 2001 Kevin Steves. All rights reserved.
18 * Redistribution and use in source and binary forms, with or without
19 * modification, are permitted provided that the following conditions
21 * 1. Redistributions of source code must retain the above copyright
22 * notice, this list of conditions and the following disclaimer.
23 * 2. Redistributions in binary form must reproduce the above copyright
24 * notice, this list of conditions and the following disclaimer in the
25 * documentation and/or other materials provided with the distribution.
27 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
28 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
29 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
30 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
31 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
32 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
33 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
34 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
35 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
36 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
40 * Encoding and decoding of terminal modes in a portable way.
41 * Much of the format is defined in ttymodes.h; it is included multiple times
42 * into this file with the appropriate macro definitions to generate the
48 #include <sys/types.h>
63 * uint32 (u_int) follows speed.
65 #define TTY_OP_ISPEED 128
66 #define TTY_OP_OSPEED 129
69 * Converts POSIX speed_t to a baud rate. The values of the
70 * constants for speed_t are not themselves portable.
73 speed_to_baud(speed_t speed)
159 * Converts a numeric baud rate to a POSIX speed_t.
162 baud_to_speed(int baud)
248 * Encode a special character into SSH line format.
251 special_char_encode(cc_t c)
253 #ifdef _POSIX_VDISABLE
254 if (c == _POSIX_VDISABLE)
256 #endif /* _POSIX_VDISABLE */
261 * Decode a special character from SSH line format.
264 special_char_decode(u_int c)
266 #ifdef _POSIX_VDISABLE
268 return _POSIX_VDISABLE;
269 #endif /* _POSIX_VDISABLE */
274 * Encodes terminal modes for the terminal referenced by fd
275 * or tiop in a portable manner, and appends the modes to a packet
279 ssh_tty_make_modes(struct ssh *ssh, int fd, struct termios *tiop)
285 if ((buf = sshbuf_new()) == NULL)
286 fatal_f("sshbuf_new failed");
290 debug_f("no fd or tio");
293 if (tcgetattr(fd, &tio) == -1) {
294 logit("tcgetattr: %.100s", strerror(errno));
300 /* Store input and output baud rates. */
301 obaud = speed_to_baud(cfgetospeed(&tio));
302 ibaud = speed_to_baud(cfgetispeed(&tio));
303 if ((r = sshbuf_put_u8(buf, TTY_OP_OSPEED)) != 0 ||
304 (r = sshbuf_put_u32(buf, obaud)) != 0 ||
305 (r = sshbuf_put_u8(buf, TTY_OP_ISPEED)) != 0 ||
306 (r = sshbuf_put_u32(buf, ibaud)) != 0)
307 fatal_fr(r, "compose");
309 /* Store values of mode flags. */
310 #define TTYCHAR(NAME, OP) \
311 if ((r = sshbuf_put_u8(buf, OP)) != 0 || \
312 (r = sshbuf_put_u32(buf, \
313 special_char_encode(tio.c_cc[NAME]))) != 0) \
314 fatal_fr(r, "compose %s", #NAME);
316 #define SSH_TTYMODE_IUTF8 42 /* for SSH_BUG_UTF8TTYMODE */
318 #define TTYMODE(NAME, FIELD, OP) \
319 if (OP == SSH_TTYMODE_IUTF8 && (ssh->compat & SSH_BUG_UTF8TTYMODE)) { \
320 debug3_f("SSH_BUG_UTF8TTYMODE"); \
321 } else if ((r = sshbuf_put_u8(buf, OP)) != 0 || \
322 (r = sshbuf_put_u32(buf, ((tio.FIELD & NAME) != 0))) != 0) \
323 fatal_fr(r, "compose %s", #NAME);
325 #include "ttymodes.h"
331 /* Mark end of mode data. */
332 if ((r = sshbuf_put_u8(buf, TTY_OP_END)) != 0 ||
333 (r = sshpkt_put_stringb(ssh, buf)) != 0)
334 fatal_fr(r, "compose end");
339 * Decodes terminal modes for the terminal referenced by fd in a portable
340 * manner from a packet being read.
343 ssh_tty_parse_modes(struct ssh *ssh, int fd)
353 if ((r = sshpkt_get_string_direct(ssh, &data, &len)) != 0)
354 fatal_fr(r, "parse");
357 if ((buf = sshbuf_from(data, len)) == NULL) {
358 error_f("sshbuf_from failed");
363 * Get old attributes for the terminal. We will modify these
364 * flags. I am hoping that if there are any machine-specific
365 * modes, they will initially have reasonable values.
367 if (tcgetattr(fd, &tio) == -1) {
368 logit("tcgetattr: %.100s", strerror(errno));
372 while (sshbuf_len(buf) > 0) {
373 if ((r = sshbuf_get_u8(buf, &opcode)) != 0)
374 fatal_fr(r, "parse opcode");
380 if ((r = sshbuf_get_u32(buf, &baud)) != 0)
381 fatal_fr(r, "parse ispeed");
383 cfsetispeed(&tio, baud_to_speed(baud)) == -1)
384 error("cfsetispeed failed for %d", baud);
388 if ((r = sshbuf_get_u32(buf, &baud)) != 0)
389 fatal_fr(r, "parse ospeed");
391 cfsetospeed(&tio, baud_to_speed(baud)) == -1)
392 error("cfsetospeed failed for %d", baud);
395 #define TTYCHAR(NAME, OP) \
397 if ((r = sshbuf_get_u32(buf, &u)) != 0) \
398 fatal_fr(r, "parse %s", #NAME); \
399 tio.c_cc[NAME] = special_char_decode(u); \
401 #define TTYMODE(NAME, FIELD, OP) \
403 if ((r = sshbuf_get_u32(buf, &u)) != 0) \
404 fatal_fr(r, "parse %s", #NAME); \
408 tio.FIELD &= ~NAME; \
411 #include "ttymodes.h"
417 debug("Ignoring unsupported tty mode opcode %d (0x%x)",
421 * Opcodes 1 to 159 are defined to have a uint32
423 * Opcodes 160 to 255 are undefined and cause parsing
426 if (opcode > 0 && opcode < 160) {
427 if ((r = sshbuf_get_u32(buf, NULL)) != 0)
428 fatal_fr(r, "parse arg");
431 logit_f("unknown opcode %d", opcode);
438 len = sshbuf_len(buf);
441 logit_f("%zu bytes left", len);
442 return; /* Don't process bytes passed */
445 return; /* Packet parsed ok but tcgetattr() failed */
447 /* Set the new modes for the terminal. */
448 if (tcsetattr(fd, TCSANOW, &tio) == -1)
449 logit("Setting tty modes failed: %.100s", strerror(errno));