ttymodes.c revision 65668
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 * Encoding and decoding of terminal modes in a portable way. 6 * Much of the format is defined in ttymodes.h; it is included multiple times 7 * into this file with the appropriate macro definitions to generate the 8 * suitable code. 9 * 10 * As far as I am concerned, the code I have written for this software 11 * can be used freely for any purpose. Any derived versions of this 12 * software must be clearly marked as such, and if the derived work is 13 * incompatible with the protocol description in the RFC file, it must be 14 * called by a name other than "ssh" or "Secure Shell". 15 */ 16 17#include "includes.h" 18RCSID("$OpenBSD: ttymodes.c,v 1.8 2000/09/07 20:27:55 deraadt Exp $"); 19 20#include "packet.h" 21#include "ssh.h" 22 23#define TTY_OP_END 0 24#define TTY_OP_ISPEED 192 /* int follows */ 25#define TTY_OP_OSPEED 193 /* int follows */ 26 27/* 28 * Converts POSIX speed_t to a baud rate. The values of the 29 * constants for speed_t are not themselves portable. 30 */ 31static int 32speed_to_baud(speed_t speed) 33{ 34 switch (speed) { 35 case B0: 36 return 0; 37 case B50: 38 return 50; 39 case B75: 40 return 75; 41 case B110: 42 return 110; 43 case B134: 44 return 134; 45 case B150: 46 return 150; 47 case B200: 48 return 200; 49 case B300: 50 return 300; 51 case B600: 52 return 600; 53 case B1200: 54 return 1200; 55 case B1800: 56 return 1800; 57 case B2400: 58 return 2400; 59 case B4800: 60 return 4800; 61 case B9600: 62 return 9600; 63 64#ifdef B19200 65 case B19200: 66 return 19200; 67#else /* B19200 */ 68#ifdef EXTA 69 case EXTA: 70 return 19200; 71#endif /* EXTA */ 72#endif /* B19200 */ 73 74#ifdef B38400 75 case B38400: 76 return 38400; 77#else /* B38400 */ 78#ifdef EXTB 79 case EXTB: 80 return 38400; 81#endif /* EXTB */ 82#endif /* B38400 */ 83 84#ifdef B7200 85 case B7200: 86 return 7200; 87#endif /* B7200 */ 88#ifdef B14400 89 case B14400: 90 return 14400; 91#endif /* B14400 */ 92#ifdef B28800 93 case B28800: 94 return 28800; 95#endif /* B28800 */ 96#ifdef B57600 97 case B57600: 98 return 57600; 99#endif /* B57600 */ 100#ifdef B76800 101 case B76800: 102 return 76800; 103#endif /* B76800 */ 104#ifdef B115200 105 case B115200: 106 return 115200; 107#endif /* B115200 */ 108#ifdef B230400 109 case B230400: 110 return 230400; 111#endif /* B230400 */ 112 default: 113 return 9600; 114 } 115} 116 117/* 118 * Converts a numeric baud rate to a POSIX speed_t. 119 */ 120static speed_t 121baud_to_speed(int baud) 122{ 123 switch (baud) { 124 case 0: 125 return B0; 126 case 50: 127 return B50; 128 case 75: 129 return B75; 130 case 110: 131 return B110; 132 case 134: 133 return B134; 134 case 150: 135 return B150; 136 case 200: 137 return B200; 138 case 300: 139 return B300; 140 case 600: 141 return B600; 142 case 1200: 143 return B1200; 144 case 1800: 145 return B1800; 146 case 2400: 147 return B2400; 148 case 4800: 149 return B4800; 150 case 9600: 151 return B9600; 152 153#ifdef B19200 154 case 19200: 155 return B19200; 156#else /* B19200 */ 157#ifdef EXTA 158 case 19200: 159 return EXTA; 160#endif /* EXTA */ 161#endif /* B19200 */ 162 163#ifdef B38400 164 case 38400: 165 return B38400; 166#else /* B38400 */ 167#ifdef EXTB 168 case 38400: 169 return EXTB; 170#endif /* EXTB */ 171#endif /* B38400 */ 172 173#ifdef B7200 174 case 7200: 175 return B7200; 176#endif /* B7200 */ 177#ifdef B14400 178 case 14400: 179 return B14400; 180#endif /* B14400 */ 181#ifdef B28800 182 case 28800: 183 return B28800; 184#endif /* B28800 */ 185#ifdef B57600 186 case 57600: 187 return B57600; 188#endif /* B57600 */ 189#ifdef B76800 190 case 76800: 191 return B76800; 192#endif /* B76800 */ 193#ifdef B115200 194 case 115200: 195 return B115200; 196#endif /* B115200 */ 197#ifdef B230400 198 case 230400: 199 return B230400; 200#endif /* B230400 */ 201 default: 202 return B9600; 203 } 204} 205 206/* 207 * Encodes terminal modes for the terminal referenced by fd 208 * in a portable manner, and appends the modes to a packet 209 * being constructed. 210 */ 211void 212tty_make_modes(int fd) 213{ 214 struct termios tio; 215 int baud; 216 217 if (tcgetattr(fd, &tio) < 0) { 218 packet_put_char(TTY_OP_END); 219 log("tcgetattr: %.100s", strerror(errno)); 220 return; 221 } 222 /* Store input and output baud rates. */ 223 baud = speed_to_baud(cfgetospeed(&tio)); 224 packet_put_char(TTY_OP_OSPEED); 225 packet_put_int(baud); 226 baud = speed_to_baud(cfgetispeed(&tio)); 227 packet_put_char(TTY_OP_ISPEED); 228 packet_put_int(baud); 229 230 /* Store values of mode flags. */ 231#define TTYCHAR(NAME, OP) \ 232 packet_put_char(OP); packet_put_char(tio.c_cc[NAME]); 233#define TTYMODE(NAME, FIELD, OP) \ 234 packet_put_char(OP); packet_put_char((tio.FIELD & NAME) != 0); 235#define SGTTYCHAR(NAME, OP) 236#define SGTTYMODE(NAME, FIELD, OP) 237#define SGTTYMODEN(NAME, FIELD, OP) 238 239#include "ttymodes.h" 240 241#undef TTYCHAR 242#undef TTYMODE 243#undef SGTTYCHAR 244#undef SGTTYMODE 245#undef SGTTYMODEN 246 247 /* Mark end of mode data. */ 248 packet_put_char(TTY_OP_END); 249} 250 251/* 252 * Decodes terminal modes for the terminal referenced by fd in a portable 253 * manner from a packet being read. 254 */ 255void 256tty_parse_modes(int fd, int *n_bytes_ptr) 257{ 258 struct termios tio; 259 int opcode, baud; 260 int n_bytes = 0; 261 int failure = 0; 262 263 /* 264 * Get old attributes for the terminal. We will modify these 265 * flags. I am hoping that if there are any machine-specific 266 * modes, they will initially have reasonable values. 267 */ 268 if (tcgetattr(fd, &tio) < 0) 269 failure = -1; 270 271 for (;;) { 272 n_bytes += 1; 273 opcode = packet_get_char(); 274 switch (opcode) { 275 case TTY_OP_END: 276 goto set; 277 278 case TTY_OP_ISPEED: 279 n_bytes += 4; 280 baud = packet_get_int(); 281 if (failure != -1 && cfsetispeed(&tio, baud_to_speed(baud)) < 0) 282 error("cfsetispeed failed for %d", baud); 283 break; 284 285 case TTY_OP_OSPEED: 286 n_bytes += 4; 287 baud = packet_get_int(); 288 if (failure != -1 && cfsetospeed(&tio, baud_to_speed(baud)) < 0) 289 error("cfsetospeed failed for %d", baud); 290 break; 291 292#define TTYCHAR(NAME, OP) \ 293 case OP: \ 294 n_bytes += 1; \ 295 tio.c_cc[NAME] = packet_get_char(); \ 296 break; 297#define TTYMODE(NAME, FIELD, OP) \ 298 case OP: \ 299 n_bytes += 1; \ 300 if (packet_get_char()) \ 301 tio.FIELD |= NAME; \ 302 else \ 303 tio.FIELD &= ~NAME; \ 304 break; 305#define SGTTYCHAR(NAME, OP) 306#define SGTTYMODE(NAME, FIELD, OP) 307#define SGTTYMODEN(NAME, FIELD, OP) 308 309#include "ttymodes.h" 310 311#undef TTYCHAR 312#undef TTYMODE 313#undef SGTTYCHAR 314#undef SGTTYMODE 315#undef SGTTYMODEN 316 317 default: 318 debug("Ignoring unsupported tty mode opcode %d (0x%x)", 319 opcode, opcode); 320 /* 321 * Opcodes 0 to 127 are defined to have 322 * a one-byte argument. 323 */ 324 if (opcode >= 0 && opcode < 128) { 325 n_bytes += 1; 326 (void) packet_get_char(); 327 break; 328 } else { 329 /* 330 * Opcodes 128 to 159 are defined to have 331 * an integer argument. 332 */ 333 if (opcode >= 128 && opcode < 160) { 334 n_bytes += 4; 335 (void) packet_get_int(); 336 break; 337 } 338 } 339 /* 340 * It is a truly undefined opcode (160 to 255). 341 * We have no idea about its arguments. So we 342 * must stop parsing. Note that some data may be 343 * left in the packet; hopefully there is nothing 344 * more coming after the mode data. 345 */ 346 log("parse_tty_modes: unknown opcode %d", opcode); 347 packet_integrity_check(0, 1, SSH_CMSG_REQUEST_PTY); 348 goto set; 349 } 350 } 351 352set: 353 if (*n_bytes_ptr != n_bytes) { 354 *n_bytes_ptr = n_bytes; 355 return; /* Don't process bytes passed */ 356 } 357 if (failure == -1) 358 return; /* Packet parsed ok but tty stuff failed */ 359 360 /* Set the new modes for the terminal. */ 361 if (tcsetattr(fd, TCSANOW, &tio) < 0) 362 log("Setting tty modes failed: %.100s", strerror(errno)); 363 return; 364} 365