ttymodes.c

   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"
  46 RCSID("$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  */
  68 static int
  69 speed_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  */
 157 static speed_t
 158 baud_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  * Encodes terminal modes for the terminal referenced by fd
 245  * or tiop in a portable manner, and appends the modes to a packet
 246  * being constructed.
 247  */
 248 void
 249 tty_make_modes(int fd, struct termios *tiop)
 250 {
 251         struct termios tio;
 252         int baud;
 253         Buffer buf;
 254         int tty_op_ospeed, tty_op_ispeed;
 255         void (*put_arg)(Buffer *, u_int);
 256
 257         buffer_init(&buf);
 258         if (compat20) {
 259                 tty_op_ospeed = TTY_OP_OSPEED_PROTO2;
 260                 tty_op_ispeed = TTY_OP_ISPEED_PROTO2;
 261                 put_arg = buffer_put_int;
 262         } else {
 263                 tty_op_ospeed = TTY_OP_OSPEED_PROTO1;
 264                 tty_op_ispeed = TTY_OP_ISPEED_PROTO1;
 265                 put_arg = (void (*)(Buffer *, u_int)) buffer_put_char;
 266         }
 267
 268         if (tiop == NULL) {
 269                 if (tcgetattr(fd, &tio) == -1) {
 270                         logit("tcgetattr: %.100s", strerror(errno));
 271                         goto end;
 272                 }
 273         } else
 274                 tio = *tiop;
 275
 276         /* Store input and output baud rates. */
 277         baud = speed_to_baud(cfgetospeed(&tio));
 278         debug3("tty_make_modes: ospeed %d", baud);
 279         buffer_put_char(&buf, tty_op_ospeed);
 280         buffer_put_int(&buf, baud);
 281         baud = speed_to_baud(cfgetispeed(&tio));
 282         debug3("tty_make_modes: ispeed %d", baud);
 283         buffer_put_char(&buf, tty_op_ispeed);
 284         buffer_put_int(&buf, baud);
 285
 286         /* Store values of mode flags. */
 287 #define TTYCHAR(NAME, OP) \
 288         debug3("tty_make_modes: %d %d", OP, tio.c_cc[NAME]); \
 289         buffer_put_char(&buf, OP); \
 290         put_arg(&buf, tio.c_cc[NAME]);
 291
 292 #define TTYMODE(NAME, FIELD, OP) \
 293         debug3("tty_make_modes: %d %d", OP, ((tio.FIELD & NAME) != 0)); \
 294         buffer_put_char(&buf, OP); \
 295         put_arg(&buf, ((tio.FIELD & NAME) != 0));
 296
 297 #include "ttymodes.h"
 298
 299 #undef TTYCHAR
 300 #undef TTYMODE
 301
 302 end:
 303         /* Mark end of mode data. */
 304         buffer_put_char(&buf, TTY_OP_END);
 305         if (compat20)
 306                 packet_put_string(buffer_ptr(&buf), buffer_len(&buf));
 307         else
 308                 packet_put_raw(buffer_ptr(&buf), buffer_len(&buf));
 309         buffer_free(&buf);
 310 }
 311
 312 /*
 313  * Decodes terminal modes for the terminal referenced by fd in a portable
 314  * manner from a packet being read.
 315  */
 316 void
 317 tty_parse_modes(int fd, int *n_bytes_ptr)
 318 {
 319         struct termios tio;
 320         int opcode, baud;
 321         int n_bytes = 0;
 322         int failure = 0;
 323         u_int (*get_arg)(void);
 324         int arg, arg_size;
 325
 326         if (compat20) {
 327                 *n_bytes_ptr = packet_get_int();
 328                 debug3("tty_parse_modes: SSH2 n_bytes %d", *n_bytes_ptr);
 329                 if (*n_bytes_ptr == 0)
 330                         return;
 331                 get_arg = packet_get_int;
 332                 arg_size = 4;
 333         } else {
 334                 get_arg = packet_get_char;
 335                 arg_size = 1;
 336         }
 337
 338         /*
 339          * Get old attributes for the terminal.  We will modify these
 340          * flags. I am hoping that if there are any machine-specific
 341          * modes, they will initially have reasonable values.
 342          */
 343         if (tcgetattr(fd, &tio) == -1) {
 344                 logit("tcgetattr: %.100s", strerror(errno));
 345                 failure = -1;
 346         }
 347
 348         for (;;) {
 349                 n_bytes += 1;
 350                 opcode = packet_get_char();
 351                 switch (opcode) {
 352                 case TTY_OP_END:
 353                         goto set;
 354
 355                 /* XXX: future conflict possible */
 356                 case TTY_OP_ISPEED_PROTO1:
 357                 case TTY_OP_ISPEED_PROTO2:
 358                         n_bytes += 4;
 359                         baud = packet_get_int();
 360                         debug3("tty_parse_modes: ispeed %d", baud);
 361                         if (failure != -1 && cfsetispeed(&tio, baud_to_speed(baud)) == -1)
 362                                 error("cfsetispeed failed for %d", baud);
 363                         break;
 364
 365                 /* XXX: future conflict possible */
 366                 case TTY_OP_OSPEED_PROTO1:
 367                 case TTY_OP_OSPEED_PROTO2:
 368                         n_bytes += 4;
 369                         baud = packet_get_int();
 370                         debug3("tty_parse_modes: ospeed %d", baud);
 371                         if (failure != -1 && cfsetospeed(&tio, baud_to_speed(baud)) == -1)
 372                                 error("cfsetospeed failed for %d", baud);
 373                         break;
 374
 375 #define TTYCHAR(NAME, OP) \
 376         case OP: \
 377           n_bytes += arg_size; \
 378           tio.c_cc[NAME] = get_arg(); \
 379           debug3("tty_parse_modes: %d %d", OP, tio.c_cc[NAME]); \
 380           break;
 381 #define TTYMODE(NAME, FIELD, OP) \
 382         case OP: \
 383           n_bytes += arg_size; \
 384           if ((arg = get_arg())) \
 385             tio.FIELD |= NAME; \
 386           else \
 387             tio.FIELD &= ~NAME; \
 388           debug3("tty_parse_modes: %d %d", OP, arg); \
 389           break;
 390
 391 #include "ttymodes.h"
 392
 393 #undef TTYCHAR
 394 #undef TTYMODE
 395
 396                 default:
 397                         debug("Ignoring unsupported tty mode opcode %d (0x%x)",
 398                             opcode, opcode);
 399                         if (!compat20) {
 400                                 /*
 401                                  * SSH1:
 402                                  * Opcodes 1 to 127 are defined to have
 403                                  * a one-byte argument.
 404                                  * Opcodes 128 to 159 are defined to have
 405                                  * an integer argument.
 406                                  */
 407                                 if (opcode > 0 && opcode < 128) {
 408                                         n_bytes += 1;
 409                                         (void) packet_get_char();
 410                                         break;
 411                                 } else if (opcode >= 128 && opcode < 160) {
 412                                         n_bytes += 4;
 413                                         (void) packet_get_int();
 414                                         break;
 415                                 } else {
 416                                         /*
 417                                          * It is a truly undefined opcode (160 to 255).
 418                                          * We have no idea about its arguments.  So we
 419                                          * must stop parsing.  Note that some data may be
 420                                          * left in the packet; hopefully there is nothing
 421                                          * more coming after the mode data.
 422                                          */
 423                                         logit("parse_tty_modes: unknown opcode %d", opcode);
 424                                         goto set;
 425                                 }
 426                         } else {
 427                                 /*
 428                                  * SSH2:
 429                                  * Opcodes 1 to 159 are defined to have
 430                                  * a uint32 argument.
 431                                  * Opcodes 160 to 255 are undefined and
 432                                  * cause parsing to stop.
 433                                  */
 434                                 if (opcode > 0 && opcode < 160) {
 435                                         n_bytes += 4;
 436                                         (void) packet_get_int();
 437                                         break;
 438                                 } else {
 439                                         logit("parse_tty_modes: unknown opcode %d", opcode);
 440                                         goto set;
 441                                 }
 442                         }
 443                 }
 444         }
 445
 446 set:
 447         if (*n_bytes_ptr != n_bytes) {
 448                 *n_bytes_ptr = n_bytes;
 449                 logit("parse_tty_modes: n_bytes_ptr != n_bytes: %d %d",
 450                     *n_bytes_ptr, n_bytes);
 451                 return;         /* Don't process bytes passed */
 452         }
 453         if (failure == -1)
 454                 return;         /* Packet parsed ok but tcgetattr() failed */
 455
 456         /* Set the new modes for the terminal. */
 457         if (tcsetattr(fd, TCSANOW, &tio) == -1)
 458                 logit("Setting tty modes failed: %.100s", strerror(errno));
 459 }