1 /* $NetBSD: ttymodes.c,v 1.5 2016/08/02 13:45:12 christos Exp $ */ 2 /* $OpenBSD: ttymodes.c,v 1.30 2016/05/04 14:22:33 markus Exp $ */ 3 /* 4 * Author: Tatu Ylonen <ylo@cs.hut.fi> 5 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland 6 * All rights reserved 7 * 8 * As far as I am concerned, the code I have written for this software 9 * can be used freely for any purpose. Any derived versions of this 10 * software must be clearly marked as such, and if the derived work is 11 * incompatible with the protocol description in the RFC file, it must be 12 * called by a name other than "ssh" or "Secure Shell". 13 */ 14 15 /* 16 * SSH2 tty modes support by Kevin Steves. 17 * Copyright (c) 2001 Kevin Steves. All rights reserved. 18 * 19 * Redistribution and use in source and binary forms, with or without 20 * modification, are permitted provided that the following conditions 21 * are met: 22 * 1. Redistributions of source code must retain the above copyright 23 * notice, this list of conditions and the following disclaimer. 24 * 2. Redistributions in binary form must reproduce the above copyright 25 * notice, this list of conditions and the following disclaimer in the 26 * documentation and/or other materials provided with the distribution. 27 * 28 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 29 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 30 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 31 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 32 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 33 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 34 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 35 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 36 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 37 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 38 */ 39 40 /* 41 * Encoding and decoding of terminal modes in a portable way. 42 * Much of the format is defined in ttymodes.h; it is included multiple times 43 * into this file with the appropriate macro definitions to generate the 44 * suitable code. 45 */ 46 47 #include "includes.h" 48 __RCSID("$NetBSD: ttymodes.c,v 1.5 2016/08/02 13:45:12 christos Exp $"); 49 #include <sys/types.h> 50 51 #include <errno.h> 52 #include <string.h> 53 #include <termios.h> 54 #include <stdarg.h> 55 56 #include "packet.h" 57 #include "log.h" 58 #include "compat.h" 59 #include "buffer.h" 60 61 #define TTY_OP_END 0 62 /* 63 * uint32 (u_int) follows speed in SSH1 and SSH2 64 */ 65 #define TTY_OP_ISPEED_PROTO1 192 66 #define TTY_OP_OSPEED_PROTO1 193 67 #define TTY_OP_ISPEED_PROTO2 128 68 #define TTY_OP_OSPEED_PROTO2 129 69 70 /* 71 * Converts POSIX speed_t to a baud rate. The values of the 72 * constants for speed_t are not themselves portable. 73 */ 74 static int 75 speed_to_baud(speed_t speed) 76 { 77 switch (speed) { 78 case B0: 79 return 0; 80 case B50: 81 return 50; 82 case B75: 83 return 75; 84 case B110: 85 return 110; 86 case B134: 87 return 134; 88 case B150: 89 return 150; 90 case B200: 91 return 200; 92 case B300: 93 return 300; 94 case B600: 95 return 600; 96 case B1200: 97 return 1200; 98 case B1800: 99 return 1800; 100 case B2400: 101 return 2400; 102 case B4800: 103 return 4800; 104 case B9600: 105 return 9600; 106 107 #ifdef B19200 108 case B19200: 109 return 19200; 110 #else /* B19200 */ 111 #ifdef EXTA 112 case EXTA: 113 return 19200; 114 #endif /* EXTA */ 115 #endif /* B19200 */ 116 117 #ifdef B38400 118 case B38400: 119 return 38400; 120 #else /* B38400 */ 121 #ifdef EXTB 122 case EXTB: 123 return 38400; 124 #endif /* EXTB */ 125 #endif /* B38400 */ 126 127 #ifdef B7200 128 case B7200: 129 return 7200; 130 #endif /* B7200 */ 131 #ifdef B14400 132 case B14400: 133 return 14400; 134 #endif /* B14400 */ 135 #ifdef B28800 136 case B28800: 137 return 28800; 138 #endif /* B28800 */ 139 #ifdef B57600 140 case B57600: 141 return 57600; 142 #endif /* B57600 */ 143 #ifdef B76800 144 case B76800: 145 return 76800; 146 #endif /* B76800 */ 147 #ifdef B115200 148 case B115200: 149 return 115200; 150 #endif /* B115200 */ 151 #ifdef B230400 152 case B230400: 153 return 230400; 154 #endif /* B230400 */ 155 default: 156 return 9600; 157 } 158 } 159 160 /* 161 * Converts a numeric baud rate to a POSIX speed_t. 162 */ 163 static speed_t 164 baud_to_speed(int baud) 165 { 166 switch (baud) { 167 case 0: 168 return B0; 169 case 50: 170 return B50; 171 case 75: 172 return B75; 173 case 110: 174 return B110; 175 case 134: 176 return B134; 177 case 150: 178 return B150; 179 case 200: 180 return B200; 181 case 300: 182 return B300; 183 case 600: 184 return B600; 185 case 1200: 186 return B1200; 187 case 1800: 188 return B1800; 189 case 2400: 190 return B2400; 191 case 4800: 192 return B4800; 193 case 9600: 194 return B9600; 195 196 #ifdef B19200 197 case 19200: 198 return B19200; 199 #else /* B19200 */ 200 #ifdef EXTA 201 case 19200: 202 return EXTA; 203 #endif /* EXTA */ 204 #endif /* B19200 */ 205 206 #ifdef B38400 207 case 38400: 208 return B38400; 209 #else /* B38400 */ 210 #ifdef EXTB 211 case 38400: 212 return EXTB; 213 #endif /* EXTB */ 214 #endif /* B38400 */ 215 216 #ifdef B7200 217 case 7200: 218 return B7200; 219 #endif /* B7200 */ 220 #ifdef B14400 221 case 14400: 222 return B14400; 223 #endif /* B14400 */ 224 #ifdef B28800 225 case 28800: 226 return B28800; 227 #endif /* B28800 */ 228 #ifdef B57600 229 case 57600: 230 return B57600; 231 #endif /* B57600 */ 232 #ifdef B76800 233 case 76800: 234 return B76800; 235 #endif /* B76800 */ 236 #ifdef B115200 237 case 115200: 238 return B115200; 239 #endif /* B115200 */ 240 #ifdef B230400 241 case 230400: 242 return B230400; 243 #endif /* B230400 */ 244 default: 245 return B9600; 246 } 247 } 248 249 /* 250 * Encode a special character into SSH line format. 251 */ 252 static u_int 253 special_char_encode(cc_t c) 254 { 255 #ifdef _POSIX_VDISABLE 256 if (c == _POSIX_VDISABLE) 257 return 255; 258 #endif /* _POSIX_VDISABLE */ 259 return c; 260 } 261 /* 262 * Decode a special character from SSH line format. 263 */ 264 static cc_t 265 special_char_decode(u_int c) 266 { 267 #ifdef _POSIX_VDISABLE 268 if (c == 255) 269 return _POSIX_VDISABLE; 270 #endif /* _POSIX_VDISABLE */ 271 return c; 272 } 273 274 /* 275 * Encodes terminal modes for the terminal referenced by fd 276 * or tiop in a portable manner, and appends the modes to a packet 277 * being constructed. 278 */ 279 void 280 tty_make_modes(int fd, struct termios *tiop) 281 { 282 struct termios tio; 283 int baud; 284 Buffer buf; 285 int tty_op_ospeed, tty_op_ispeed; 286 void (*put_arg)(Buffer *, u_int); 287 288 buffer_init(&buf); 289 if (compat20) { 290 tty_op_ospeed = TTY_OP_OSPEED_PROTO2; 291 tty_op_ispeed = TTY_OP_ISPEED_PROTO2; 292 put_arg = buffer_put_int; 293 } else { 294 tty_op_ospeed = TTY_OP_OSPEED_PROTO1; 295 tty_op_ispeed = TTY_OP_ISPEED_PROTO1; 296 put_arg = (void (*)(Buffer *, u_int)) buffer_put_char; 297 } 298 299 if (tiop == NULL) { 300 if (fd == -1) { 301 debug("tty_make_modes: no fd or tio"); 302 goto end; 303 } 304 if (tcgetattr(fd, &tio) == -1) { 305 logit("tcgetattr: %.100s", strerror(errno)); 306 goto end; 307 } 308 } else 309 tio = *tiop; 310 311 /* Store input and output baud rates. */ 312 baud = speed_to_baud(cfgetospeed(&tio)); 313 buffer_put_char(&buf, tty_op_ospeed); 314 buffer_put_int(&buf, baud); 315 baud = speed_to_baud(cfgetispeed(&tio)); 316 buffer_put_char(&buf, tty_op_ispeed); 317 buffer_put_int(&buf, baud); 318 319 /* Store values of mode flags. */ 320 #define TTYCHAR(NAME, OP) \ 321 buffer_put_char(&buf, OP); \ 322 put_arg(&buf, special_char_encode(tio.c_cc[NAME])); 323 324 #define TTYMODE(NAME, FIELD, OP) \ 325 buffer_put_char(&buf, OP); \ 326 put_arg(&buf, ((tio.FIELD & NAME) != 0)); 327 328 #include "ttymodes.h" 329 330 #undef TTYCHAR 331 #undef TTYMODE 332 333 end: 334 /* Mark end of mode data. */ 335 buffer_put_char(&buf, TTY_OP_END); 336 if (compat20) 337 packet_put_string(buffer_ptr(&buf), buffer_len(&buf)); 338 else 339 packet_put_raw(buffer_ptr(&buf), buffer_len(&buf)); 340 buffer_free(&buf); 341 } 342 343 /* 344 * Decodes terminal modes for the terminal referenced by fd in a portable 345 * manner from a packet being read. 346 */ 347 void 348 tty_parse_modes(int fd, int *n_bytes_ptr) 349 { 350 struct termios tio; 351 int opcode, baud; 352 int n_bytes = 0; 353 int failure = 0; 354 u_int (*get_arg)(void); 355 int arg_size; 356 357 if (compat20) { 358 *n_bytes_ptr = packet_get_int(); 359 if (*n_bytes_ptr == 0) 360 return; 361 get_arg = packet_get_int; 362 arg_size = 4; 363 } else { 364 get_arg = packet_get_char; 365 arg_size = 1; 366 } 367 368 /* 369 * Get old attributes for the terminal. We will modify these 370 * flags. I am hoping that if there are any machine-specific 371 * modes, they will initially have reasonable values. 372 */ 373 if (tcgetattr(fd, &tio) == -1) { 374 logit("tcgetattr: %.100s", strerror(errno)); 375 failure = -1; 376 } 377 378 for (;;) { 379 n_bytes += 1; 380 opcode = packet_get_char(); 381 switch (opcode) { 382 case TTY_OP_END: 383 goto set; 384 385 /* XXX: future conflict possible */ 386 case TTY_OP_ISPEED_PROTO1: 387 case TTY_OP_ISPEED_PROTO2: 388 n_bytes += 4; 389 baud = packet_get_int(); 390 if (failure != -1 && 391 cfsetispeed(&tio, baud_to_speed(baud)) == -1) 392 error("cfsetispeed failed for %d", baud); 393 break; 394 395 /* XXX: future conflict possible */ 396 case TTY_OP_OSPEED_PROTO1: 397 case TTY_OP_OSPEED_PROTO2: 398 n_bytes += 4; 399 baud = packet_get_int(); 400 if (failure != -1 && 401 cfsetospeed(&tio, baud_to_speed(baud)) == -1) 402 error("cfsetospeed failed for %d", baud); 403 break; 404 405 #define TTYCHAR(NAME, OP) \ 406 case OP: \ 407 n_bytes += arg_size; \ 408 tio.c_cc[NAME] = special_char_decode(get_arg()); \ 409 break; 410 #define TTYMODE(NAME, FIELD, OP) \ 411 case OP: \ 412 n_bytes += arg_size; \ 413 if (get_arg()) \ 414 tio.FIELD |= NAME; \ 415 else \ 416 tio.FIELD &= ~NAME; \ 417 break; 418 419 #include "ttymodes.h" 420 421 #undef TTYCHAR 422 #undef TTYMODE 423 424 default: 425 debug("Ignoring unsupported tty mode opcode %d (0x%x)", 426 opcode, opcode); 427 if (!compat20) { 428 /* 429 * SSH1: 430 * Opcodes 1 to 127 are defined to have 431 * a one-byte argument. 432 * Opcodes 128 to 159 are defined to have 433 * an integer argument. 434 */ 435 if (opcode > 0 && opcode < 128) { 436 n_bytes += 1; 437 (void) packet_get_char(); 438 break; 439 } else if (opcode >= 128 && opcode < 160) { 440 n_bytes += 4; 441 (void) packet_get_int(); 442 break; 443 } else { 444 /* 445 * It is a truly undefined opcode (160 to 255). 446 * We have no idea about its arguments. So we 447 * must stop parsing. Note that some data 448 * may be left in the packet; hopefully there 449 * is nothing more coming after the mode data. 450 */ 451 logit("parse_tty_modes: unknown opcode %d", 452 opcode); 453 goto set; 454 } 455 } else { 456 /* 457 * SSH2: 458 * Opcodes 1 to 159 are defined to have 459 * a uint32 argument. 460 * Opcodes 160 to 255 are undefined and 461 * cause parsing to stop. 462 */ 463 if (opcode > 0 && opcode < 160) { 464 n_bytes += 4; 465 (void) packet_get_int(); 466 break; 467 } else { 468 logit("parse_tty_modes: unknown opcode %d", 469 opcode); 470 goto set; 471 } 472 } 473 } 474 } 475 476 set: 477 if (*n_bytes_ptr != n_bytes) { 478 *n_bytes_ptr = n_bytes; 479 logit("parse_tty_modes: n_bytes_ptr != n_bytes: %d %d", 480 *n_bytes_ptr, n_bytes); 481 return; /* Don't process bytes passed */ 482 } 483 if (failure == -1) 484 return; /* Packet parsed ok but tcgetattr() failed */ 485 486 /* Set the new modes for the terminal. */ 487 if (tcsetattr(fd, TCSANOW, &tio) == -1) 488 logit("Setting tty modes failed: %.100s", strerror(errno)); 489 } 490