ttymodes.c revision 149749
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 * Encoding and decoding of terminal modes in a portable way. 40 * Much of the format is defined in ttymodes.h; it is included multiple times 41 * into this file with the appropriate macro definitions to generate the 42 * suitable code. 43 */ 44 45#include "includes.h" 46RCSID("$OpenBSD: ttymodes.c,v 1.19 2003/04/08 20:21:29 itojun Exp $"); 47 48#include "packet.h" 49#include "log.h" 50#include "ssh1.h" 51#include "compat.h" 52#include "buffer.h" 53#include "bufaux.h" 54 55#define TTY_OP_END 0 56/* 57 * uint32 (u_int) follows speed in SSH1 and SSH2 58 */ 59#define TTY_OP_ISPEED_PROTO1 192 60#define TTY_OP_OSPEED_PROTO1 193 61#define TTY_OP_ISPEED_PROTO2 128 62#define TTY_OP_OSPEED_PROTO2 129 63 64/* 65 * Converts POSIX speed_t to a baud rate. The values of the 66 * constants for speed_t are not themselves portable. 67 */ 68static int 69speed_to_baud(speed_t speed) 70{ 71 switch (speed) { 72 case B0: 73 return 0; 74 case B50: 75 return 50; 76 case B75: 77 return 75; 78 case B110: 79 return 110; 80 case B134: 81 return 134; 82 case B150: 83 return 150; 84 case B200: 85 return 200; 86 case B300: 87 return 300; 88 case B600: 89 return 600; 90 case B1200: 91 return 1200; 92 case B1800: 93 return 1800; 94 case B2400: 95 return 2400; 96 case B4800: 97 return 4800; 98 case B9600: 99 return 9600; 100 101#ifdef B19200 102 case B19200: 103 return 19200; 104#else /* B19200 */ 105#ifdef EXTA 106 case EXTA: 107 return 19200; 108#endif /* EXTA */ 109#endif /* B19200 */ 110 111#ifdef B38400 112 case B38400: 113 return 38400; 114#else /* B38400 */ 115#ifdef EXTB 116 case EXTB: 117 return 38400; 118#endif /* EXTB */ 119#endif /* B38400 */ 120 121#ifdef B7200 122 case B7200: 123 return 7200; 124#endif /* B7200 */ 125#ifdef B14400 126 case B14400: 127 return 14400; 128#endif /* B14400 */ 129#ifdef B28800 130 case B28800: 131 return 28800; 132#endif /* B28800 */ 133#ifdef B57600 134 case B57600: 135 return 57600; 136#endif /* B57600 */ 137#ifdef B76800 138 case B76800: 139 return 76800; 140#endif /* B76800 */ 141#ifdef B115200 142 case B115200: 143 return 115200; 144#endif /* B115200 */ 145#ifdef B230400 146 case B230400: 147 return 230400; 148#endif /* B230400 */ 149 default: 150 return 9600; 151 } 152} 153 154/* 155 * Converts a numeric baud rate to a POSIX speed_t. 156 */ 157static speed_t 158baud_to_speed(int baud) 159{ 160 switch (baud) { 161 case 0: 162 return B0; 163 case 50: 164 return B50; 165 case 75: 166 return B75; 167 case 110: 168 return B110; 169 case 134: 170 return B134; 171 case 150: 172 return B150; 173 case 200: 174 return B200; 175 case 300: 176 return B300; 177 case 600: 178 return B600; 179 case 1200: 180 return B1200; 181 case 1800: 182 return B1800; 183 case 2400: 184 return B2400; 185 case 4800: 186 return B4800; 187 case 9600: 188 return B9600; 189 190#ifdef B19200 191 case 19200: 192 return B19200; 193#else /* B19200 */ 194#ifdef EXTA 195 case 19200: 196 return EXTA; 197#endif /* EXTA */ 198#endif /* B19200 */ 199 200#ifdef B38400 201 case 38400: 202 return B38400; 203#else /* B38400 */ 204#ifdef EXTB 205 case 38400: 206 return EXTB; 207#endif /* EXTB */ 208#endif /* B38400 */ 209 210#ifdef B7200 211 case 7200: 212 return B7200; 213#endif /* B7200 */ 214#ifdef B14400 215 case 14400: 216 return B14400; 217#endif /* B14400 */ 218#ifdef B28800 219 case 28800: 220 return B28800; 221#endif /* B28800 */ 222#ifdef B57600 223 case 57600: 224 return B57600; 225#endif /* B57600 */ 226#ifdef B76800 227 case 76800: 228 return B76800; 229#endif /* B76800 */ 230#ifdef B115200 231 case 115200: 232 return B115200; 233#endif /* B115200 */ 234#ifdef B230400 235 case 230400: 236 return B230400; 237#endif /* B230400 */ 238 default: 239 return B9600; 240 } 241} 242 243/* 244 * Encode a special character into SSH line format. 245 */ 246static u_int 247special_char_encode(cc_t c) 248{ 249#ifdef _POSIX_VDISABLE 250 if (c == _POSIX_VDISABLE) 251 return 255; 252#endif /* _POSIX_VDISABLE */ 253 return c; 254} 255 256/* 257 * Decode a special character from SSH line format. 258 */ 259static cc_t 260special_char_decode(u_int c) 261{ 262#ifdef _POSIX_VDISABLE 263 if (c == 255) 264 return _POSIX_VDISABLE; 265#endif /* _POSIX_VDISABLE */ 266 return c; 267} 268 269/* 270 * Encodes terminal modes for the terminal referenced by fd 271 * or tiop in a portable manner, and appends the modes to a packet 272 * being constructed. 273 */ 274void 275tty_make_modes(int fd, struct termios *tiop) 276{ 277 struct termios tio; 278 int baud; 279 Buffer buf; 280 int tty_op_ospeed, tty_op_ispeed; 281 void (*put_arg)(Buffer *, u_int); 282 283 buffer_init(&buf); 284 if (compat20) { 285 tty_op_ospeed = TTY_OP_OSPEED_PROTO2; 286 tty_op_ispeed = TTY_OP_ISPEED_PROTO2; 287 put_arg = buffer_put_int; 288 } else { 289 tty_op_ospeed = TTY_OP_OSPEED_PROTO1; 290 tty_op_ispeed = TTY_OP_ISPEED_PROTO1; 291 put_arg = (void (*)(Buffer *, u_int)) buffer_put_char; 292 } 293 294 if (tiop == NULL) { 295 if (tcgetattr(fd, &tio) == -1) { 296 logit("tcgetattr: %.100s", strerror(errno)); 297 goto end; 298 } 299 } else 300 tio = *tiop; 301 302 /* Store input and output baud rates. */ 303 baud = speed_to_baud(cfgetospeed(&tio)); 304 debug3("tty_make_modes: ospeed %d", baud); 305 buffer_put_char(&buf, tty_op_ospeed); 306 buffer_put_int(&buf, baud); 307 baud = speed_to_baud(cfgetispeed(&tio)); 308 debug3("tty_make_modes: ispeed %d", baud); 309 buffer_put_char(&buf, tty_op_ispeed); 310 buffer_put_int(&buf, baud); 311 312 /* Store values of mode flags. */ 313#define TTYCHAR(NAME, OP) \ 314 debug3("tty_make_modes: %d %d", OP, tio.c_cc[NAME]); \ 315 buffer_put_char(&buf, OP); \ 316 put_arg(&buf, special_char_encode(tio.c_cc[NAME])); 317 318#define TTYMODE(NAME, FIELD, OP) \ 319 debug3("tty_make_modes: %d %d", OP, ((tio.FIELD & NAME) != 0)); \ 320 buffer_put_char(&buf, OP); \ 321 put_arg(&buf, ((tio.FIELD & NAME) != 0)); 322 323#include "ttymodes.h" 324 325#undef TTYCHAR 326#undef TTYMODE 327 328end: 329 /* Mark end of mode data. */ 330 buffer_put_char(&buf, TTY_OP_END); 331 if (compat20) 332 packet_put_string(buffer_ptr(&buf), buffer_len(&buf)); 333 else 334 packet_put_raw(buffer_ptr(&buf), buffer_len(&buf)); 335 buffer_free(&buf); 336} 337 338/* 339 * Decodes terminal modes for the terminal referenced by fd in a portable 340 * manner from a packet being read. 341 */ 342void 343tty_parse_modes(int fd, int *n_bytes_ptr) 344{ 345 struct termios tio; 346 int opcode, baud; 347 int n_bytes = 0; 348 int failure = 0; 349 u_int (*get_arg)(void); 350 int arg, arg_size; 351 352 if (compat20) { 353 *n_bytes_ptr = packet_get_int(); 354 debug3("tty_parse_modes: SSH2 n_bytes %d", *n_bytes_ptr); 355 if (*n_bytes_ptr == 0) 356 return; 357 get_arg = packet_get_int; 358 arg_size = 4; 359 } else { 360 get_arg = packet_get_char; 361 arg_size = 1; 362 } 363 364 /* 365 * Get old attributes for the terminal. We will modify these 366 * flags. I am hoping that if there are any machine-specific 367 * modes, they will initially have reasonable values. 368 */ 369 if (tcgetattr(fd, &tio) == -1) { 370 logit("tcgetattr: %.100s", strerror(errno)); 371 failure = -1; 372 } 373 374 for (;;) { 375 n_bytes += 1; 376 opcode = packet_get_char(); 377 switch (opcode) { 378 case TTY_OP_END: 379 goto set; 380 381 /* XXX: future conflict possible */ 382 case TTY_OP_ISPEED_PROTO1: 383 case TTY_OP_ISPEED_PROTO2: 384 n_bytes += 4; 385 baud = packet_get_int(); 386 debug3("tty_parse_modes: ispeed %d", baud); 387 if (failure != -1 && cfsetispeed(&tio, baud_to_speed(baud)) == -1) 388 error("cfsetispeed failed for %d", baud); 389 break; 390 391 /* XXX: future conflict possible */ 392 case TTY_OP_OSPEED_PROTO1: 393 case TTY_OP_OSPEED_PROTO2: 394 n_bytes += 4; 395 baud = packet_get_int(); 396 debug3("tty_parse_modes: ospeed %d", baud); 397 if (failure != -1 && cfsetospeed(&tio, baud_to_speed(baud)) == -1) 398 error("cfsetospeed failed for %d", baud); 399 break; 400 401#define TTYCHAR(NAME, OP) \ 402 case OP: \ 403 n_bytes += arg_size; \ 404 tio.c_cc[NAME] = special_char_decode(get_arg()); \ 405 debug3("tty_parse_modes: %d %d", OP, tio.c_cc[NAME]); \ 406 break; 407#define TTYMODE(NAME, FIELD, OP) \ 408 case OP: \ 409 n_bytes += arg_size; \ 410 if ((arg = get_arg())) \ 411 tio.FIELD |= NAME; \ 412 else \ 413 tio.FIELD &= ~NAME; \ 414 debug3("tty_parse_modes: %d %d", OP, arg); \ 415 break; 416 417#include "ttymodes.h" 418 419#undef TTYCHAR 420#undef TTYMODE 421 422 default: 423 debug("Ignoring unsupported tty mode opcode %d (0x%x)", 424 opcode, opcode); 425 if (!compat20) { 426 /* 427 * SSH1: 428 * Opcodes 1 to 127 are defined to have 429 * a one-byte argument. 430 * Opcodes 128 to 159 are defined to have 431 * an integer argument. 432 */ 433 if (opcode > 0 && opcode < 128) { 434 n_bytes += 1; 435 (void) packet_get_char(); 436 break; 437 } else if (opcode >= 128 && opcode < 160) { 438 n_bytes += 4; 439 (void) packet_get_int(); 440 break; 441 } else { 442 /* 443 * It is a truly undefined opcode (160 to 255). 444 * We have no idea about its arguments. So we 445 * must stop parsing. Note that some data may be 446 * left in the packet; hopefully there is nothing 447 * more coming after the mode data. 448 */ 449 logit("parse_tty_modes: unknown opcode %d", opcode); 450 goto set; 451 } 452 } else { 453 /* 454 * SSH2: 455 * Opcodes 1 to 159 are defined to have 456 * a uint32 argument. 457 * Opcodes 160 to 255 are undefined and 458 * cause parsing to stop. 459 */ 460 if (opcode > 0 && opcode < 160) { 461 n_bytes += 4; 462 (void) packet_get_int(); 463 break; 464 } else { 465 logit("parse_tty_modes: unknown opcode %d", opcode); 466 goto set; 467 } 468 } 469 } 470 } 471 472set: 473 if (*n_bytes_ptr != n_bytes) { 474 *n_bytes_ptr = n_bytes; 475 logit("parse_tty_modes: n_bytes_ptr != n_bytes: %d %d", 476 *n_bytes_ptr, n_bytes); 477 return; /* Don't process bytes passed */ 478 } 479 if (failure == -1) 480 return; /* Packet parsed ok but tcgetattr() failed */ 481 482 /* Set the new modes for the terminal. */ 483 if (tcsetattr(fd, TCSANOW, &tio) == -1) 484 logit("Setting tty modes failed: %.100s", strerror(errno)); 485} 486