1/* 2 * tty.c - code for handling serial ports in pppd. 3 * 4 * Copyright (C) 2000-2002 Paul Mackerras. All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in 15 * the documentation and/or other materials provided with the 16 * distribution. 17 * 18 * 3. The name(s) of the authors of this software must not be used to 19 * endorse or promote products derived from this software without 20 * prior written permission. 21 * 22 * 4. Redistributions of any form whatsoever must retain the following 23 * acknowledgment: 24 * "This product includes software developed by Paul Mackerras 25 * <paulus@samba.org>". 26 * 27 * THE AUTHORS OF THIS SOFTWARE DISCLAIM ALL WARRANTIES WITH REGARD TO 28 * THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY 29 * AND FITNESS, IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY 30 * SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 31 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN 32 * AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING 33 * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 34 * 35 * Portions derived from main.c, which is: 36 * 37 * Copyright (c) 1984-2000 Carnegie Mellon University. All rights reserved. 38 * 39 * Redistribution and use in source and binary forms, with or without 40 * modification, are permitted provided that the following conditions 41 * are met: 42 * 43 * 1. Redistributions of source code must retain the above copyright 44 * notice, this list of conditions and the following disclaimer. 45 * 46 * 2. Redistributions in binary form must reproduce the above copyright 47 * notice, this list of conditions and the following disclaimer in 48 * the documentation and/or other materials provided with the 49 * distribution. 50 * 51 * 3. The name "Carnegie Mellon University" must not be used to 52 * endorse or promote products derived from this software without 53 * prior written permission. For permission or any legal 54 * details, please contact 55 * Office of Technology Transfer 56 * Carnegie Mellon University 57 * 5000 Forbes Avenue 58 * Pittsburgh, PA 15213-3890 59 * (412) 268-4387, fax: (412) 268-7395 60 * tech-transfer@andrew.cmu.edu 61 * 62 * 4. Redistributions of any form whatsoever must retain the following 63 * acknowledgment: 64 * "This product includes software developed by Computing Services 65 * at Carnegie Mellon University (http://www.cmu.edu/computing/)." 66 * 67 * CARNEGIE MELLON UNIVERSITY DISCLAIMS ALL WARRANTIES WITH REGARD TO 68 * THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY 69 * AND FITNESS, IN NO EVENT SHALL CARNEGIE MELLON UNIVERSITY BE LIABLE 70 * FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 71 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN 72 * AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING 73 * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 74 */ 75 76#define RCSID "$Id: tty.c,v 1.1.1.1 2008/10/15 03:30:15 james26_jang Exp $" 77 78#include <stdio.h> 79#include <ctype.h> 80#include <stdlib.h> 81#include <string.h> 82#include <unistd.h> 83#include <signal.h> 84#include <errno.h> 85#include <fcntl.h> 86#include <syslog.h> 87#include <netdb.h> 88#include <utmp.h> 89#include <pwd.h> 90#include <setjmp.h> 91#include <sys/param.h> 92#include <sys/types.h> 93#include <sys/wait.h> 94#include <sys/time.h> 95#include <sys/resource.h> 96#include <sys/stat.h> 97#include <sys/socket.h> 98#include <netinet/in.h> 99#include <arpa/inet.h> 100 101#include "pppd.h" 102#include "fsm.h" 103#include "lcp.h" 104 105void tty_process_extra_options __P((void)); 106void tty_check_options __P((void)); 107int connect_tty __P((void)); 108void disconnect_tty __P((void)); 109void tty_close_fds __P((void)); 110void cleanup_tty __P((void)); 111void tty_do_send_config __P((int, u_int32_t, int, int)); 112 113static int setdevname __P((char *, char **, int)); 114static int setspeed __P((char *, char **, int)); 115static int setxonxoff __P((char **)); 116static int setescape __P((char **)); 117static void printescape __P((option_t *, void (*)(void *, char *,...),void *)); 118static void finish_tty __P((void)); 119static int start_charshunt __P((int, int)); 120static void stop_charshunt __P((void *, int)); 121static void charshunt_done __P((void *)); 122static void charshunt __P((int, int, char *)); 123static int record_write __P((FILE *, int code, u_char *buf, int nb, 124 struct timeval *)); 125static int open_socket __P((char *)); 126static void maybe_relock __P((void *, int)); 127 128static int pty_master; /* fd for master side of pty */ 129static int pty_slave; /* fd for slave side of pty */ 130static int real_ttyfd; /* fd for actual serial port (not pty) */ 131static int ttyfd; /* Serial port file descriptor */ 132static char speed_str[16]; /* Serial port speed as string */ 133 134mode_t tty_mode = (mode_t)-1; /* Original access permissions to tty */ 135int baud_rate; /* Actual bits/second for serial device */ 136char *callback_script; /* script for doing callback */ 137int charshunt_pid; /* Process ID for charshunt */ 138int locked; /* lock() has succeeded */ 139struct stat devstat; /* result of stat() on devnam */ 140 141/* option variables */ 142int crtscts = 0; /* Use hardware flow control */ 143bool modem = 1; /* Use modem control lines */ 144int inspeed = 0; /* Input/Output speed requested */ 145bool lockflag = 0; /* Create lock file to lock the serial dev */ 146char *initializer = NULL; /* Script to initialize physical link */ 147char *connect_script = NULL; /* Script to establish physical link */ 148char *disconnect_script = NULL; /* Script to disestablish physical link */ 149char *welcomer = NULL; /* Script to run after phys link estab. */ 150char *ptycommand = NULL; /* Command to run on other side of pty */ 151bool notty = 0; /* Stdin/out is not a tty */ 152char *record_file = NULL; /* File to record chars sent/received */ 153int max_data_rate; /* max bytes/sec through charshunt */ 154bool sync_serial = 0; /* Device is synchronous serial device */ 155char *pty_socket = NULL; /* Socket to connect to pty */ 156int using_pty = 0; /* we're allocating a pty as the device */ 157 158extern uid_t uid; 159extern int kill_link; 160 161/* XXX */ 162extern int privopen; /* don't lock, open device as root */ 163 164u_int32_t xmit_accm[8]; /* extended transmit ACCM */ 165 166/* option descriptors */ 167option_t tty_options[] = { 168 /* device name must be first, or change connect_tty() below! */ 169 { "device name", o_wild, (void *) &setdevname, 170 "Serial port device name", 171 OPT_DEVNAM | OPT_PRIVFIX | OPT_NOARG | OPT_A2STRVAL | OPT_STATIC, 172 devnam}, 173 174 { "tty speed", o_wild, (void *) &setspeed, 175 "Baud rate for serial port", 176 OPT_PRIO | OPT_NOARG | OPT_A2STRVAL | OPT_STATIC, speed_str }, 177 178 { "lock", o_bool, &lockflag, 179 "Lock serial device with UUCP-style lock file", OPT_PRIO | 1 }, 180 { "nolock", o_bool, &lockflag, 181 "Don't lock serial device", OPT_PRIOSUB | OPT_PRIV }, 182 183 { "init", o_string, &initializer, 184 "A program to initialize the device", OPT_PRIO | OPT_PRIVFIX }, 185 186 { "connect", o_string, &connect_script, 187 "A program to set up a connection", OPT_PRIO | OPT_PRIVFIX }, 188 189 { "disconnect", o_string, &disconnect_script, 190 "Program to disconnect serial device", OPT_PRIO | OPT_PRIVFIX }, 191 192 { "welcome", o_string, &welcomer, 193 "Script to welcome client", OPT_PRIO | OPT_PRIVFIX }, 194 195 { "pty", o_string, &ptycommand, 196 "Script to run on pseudo-tty master side", 197 OPT_PRIO | OPT_PRIVFIX | OPT_DEVNAM }, 198 199 { "notty", o_bool, ¬ty, 200 "Input/output is not a tty", OPT_DEVNAM | 1 }, 201 202 { "socket", o_string, &pty_socket, 203 "Send and receive over socket, arg is host:port", 204 OPT_PRIO | OPT_DEVNAM }, 205 206 { "record", o_string, &record_file, 207 "Record characters sent/received to file", OPT_PRIO }, 208 209 { "crtscts", o_int, &crtscts, 210 "Set hardware (RTS/CTS) flow control", 211 OPT_PRIO | OPT_NOARG | OPT_VAL(1) }, 212 { "cdtrcts", o_int, &crtscts, 213 "Set alternate hardware (DTR/CTS) flow control", 214 OPT_PRIOSUB | OPT_NOARG | OPT_VAL(2) }, 215 { "nocrtscts", o_int, &crtscts, 216 "Disable hardware flow control", 217 OPT_PRIOSUB | OPT_NOARG | OPT_VAL(-1) }, 218 { "-crtscts", o_int, &crtscts, 219 "Disable hardware flow control", 220 OPT_PRIOSUB | OPT_ALIAS | OPT_NOARG | OPT_VAL(-1) }, 221 { "nocdtrcts", o_int, &crtscts, 222 "Disable hardware flow control", 223 OPT_PRIOSUB | OPT_ALIAS | OPT_NOARG | OPT_VAL(-1) }, 224 { "xonxoff", o_special_noarg, (void *)setxonxoff, 225 "Set software (XON/XOFF) flow control", OPT_PRIOSUB }, 226 227 { "modem", o_bool, &modem, 228 "Use modem control lines", OPT_PRIO | 1 }, 229 { "local", o_bool, &modem, 230 "Don't use modem control lines", OPT_PRIOSUB | 0 }, 231 232 { "sync", o_bool, &sync_serial, 233 "Use synchronous HDLC serial encoding", 1 }, 234 235 { "datarate", o_int, &max_data_rate, 236 "Maximum data rate in bytes/sec (with pty, notty or record option)", 237 OPT_PRIO }, 238 239 { "escape", o_special, (void *)setescape, 240 "List of character codes to escape on transmission", 241 OPT_A2PRINTER, (void *)printescape }, 242 243 { NULL } 244}; 245 246 247struct channel tty_channel = { 248 tty_options, 249 &tty_process_extra_options, 250 &tty_check_options, 251 &connect_tty, 252 &disconnect_tty, 253 &tty_establish_ppp, 254 &tty_disestablish_ppp, 255 &tty_do_send_config, 256 &tty_recv_config, 257 &cleanup_tty, 258 &tty_close_fds 259}; 260 261/* 262 * setspeed - Set the serial port baud rate. 263 * If doit is 0, the call is to check whether this option is 264 * potentially a speed value. 265 */ 266static int 267setspeed(arg, argv, doit) 268 char *arg; 269 char **argv; 270 int doit; 271{ 272 char *ptr; 273 int spd; 274 275 spd = strtol(arg, &ptr, 0); 276 if (ptr == arg || *ptr != 0 || spd == 0) 277 return 0; 278 if (doit) { 279 inspeed = spd; 280 slprintf(speed_str, sizeof(speed_str), "%d", spd); 281 } 282 return 1; 283} 284 285 286/* 287 * setdevname - Set the device name. 288 * If doit is 0, the call is to check whether this option is 289 * potentially a device name. 290 */ 291static int 292setdevname(cp, argv, doit) 293 char *cp; 294 char **argv; 295 int doit; 296{ 297 struct stat statbuf; 298 char dev[MAXPATHLEN]; 299 300 if (*cp == 0) 301 return 0; 302 303 if (strncmp("/dev/", cp, 5) != 0) { 304 strlcpy(dev, "/dev/", sizeof(dev)); 305 strlcat(dev, cp, sizeof(dev)); 306 cp = dev; 307 } 308 309 /* 310 * Check if there is a character device by this name. 311 */ 312 if (stat(cp, &statbuf) < 0) { 313 if (!doit) 314 return errno != ENOENT; 315 option_error("Couldn't stat %s: %m", cp); 316 return 0; 317 } 318 if (!S_ISCHR(statbuf.st_mode)) { 319 if (doit) 320 option_error("%s is not a character device", cp); 321 return 0; 322 } 323 324 if (doit) { 325 strlcpy(devnam, cp, sizeof(devnam)); 326 devstat = statbuf; 327 default_device = 0; 328 } 329 330 return 1; 331} 332 333static int 334setxonxoff(argv) 335 char **argv; 336{ 337 lcp_wantoptions[0].asyncmap |= 0x000A0000; /* escape ^S and ^Q */ 338 lcp_wantoptions[0].neg_asyncmap = 1; 339 340 crtscts = -2; 341 return 1; 342} 343 344/* 345 * setescape - add chars to the set we escape on transmission. 346 */ 347static int 348setescape(argv) 349 char **argv; 350{ 351 int n, ret; 352 char *p, *endp; 353 354 p = *argv; 355 ret = 1; 356 while (*p) { 357 n = strtol(p, &endp, 16); 358 if (p == endp) { 359 option_error("escape parameter contains invalid hex number '%s'", 360 p); 361 return 0; 362 } 363 p = endp; 364 if (n < 0 || n == 0x5E || n > 0xFF) { 365 option_error("can't escape character 0x%x", n); 366 ret = 0; 367 } else 368 xmit_accm[n >> 5] |= 1 << (n & 0x1F); 369 while (*p == ',' || *p == ' ') 370 ++p; 371 } 372 lcp_allowoptions[0].asyncmap = xmit_accm[0]; 373 return ret; 374} 375 376static void 377printescape(opt, printer, arg) 378 option_t *opt; 379 void (*printer) __P((void *, char *, ...)); 380 void *arg; 381{ 382 int n; 383 int first = 1; 384 385 for (n = 0; n < 256; ++n) { 386 if (n == 0x7d) 387 n += 2; /* skip 7d, 7e */ 388 if (xmit_accm[n >> 5] & (1 << (n & 0x1f))) { 389 if (!first) 390 printer(arg, ","); 391 else 392 first = 0; 393 printer(arg, "%x", n); 394 } 395 } 396 if (first) 397 printer(arg, "oops # nothing escaped"); 398} 399 400/* 401 * tty_init - do various tty-related initializations. 402 */ 403void tty_init() 404{ 405 add_notifier(&pidchange, maybe_relock, 0); 406 the_channel = &tty_channel; 407 xmit_accm[3] = 0x60000000; 408} 409 410/* 411 * tty_process_extra_options - work out which tty device we are using 412 * and read its options file. 413 */ 414void tty_process_extra_options() 415{ 416 using_pty = notty || ptycommand != NULL || pty_socket != NULL; 417 if (using_pty) 418 return; 419 if (default_device) { 420 char *p; 421 if (!isatty(0) || (p = ttyname(0)) == NULL) { 422 option_error("no device specified and stdin is not a tty"); 423 exit(EXIT_OPTION_ERROR); 424 } 425 strlcpy(devnam, p, sizeof(devnam)); 426 if (stat(devnam, &devstat) < 0) 427 fatal("Couldn't stat default device %s: %m", devnam); 428 } 429 430 431 /* 432 * Parse the tty options file. 433 * The per-tty options file should not change 434 * ptycommand, pty_socket, notty or devnam. 435 * options_for_tty doesn't override options set on the command line, 436 * except for some privileged options. 437 */ 438 if (!options_for_tty()) 439 exit(EXIT_OPTION_ERROR); 440} 441 442/* 443 * tty_check_options - do consistency checks on the options we were given. 444 */ 445void 446tty_check_options() 447{ 448 struct stat statbuf; 449 int fdflags; 450 451 if (demand && connect_script == 0) { 452 option_error("connect script is required for demand-dialling\n"); 453 exit(EXIT_OPTION_ERROR); 454 } 455 /* default holdoff to 0 if no connect script has been given */ 456 if (connect_script == 0 && !holdoff_specified) 457 holdoff = 0; 458 459 if (using_pty) { 460 if (!default_device) { 461 option_error("%s option precludes specifying device name", 462 notty? "notty": "pty"); 463 exit(EXIT_OPTION_ERROR); 464 } 465 if (ptycommand != NULL && notty) { 466 option_error("pty option is incompatible with notty option"); 467 exit(EXIT_OPTION_ERROR); 468 } 469 if (pty_socket != NULL && (ptycommand != NULL || notty)) { 470 option_error("socket option is incompatible with pty and notty"); 471 exit(EXIT_OPTION_ERROR); 472 } 473 default_device = notty; 474 lockflag = 0; 475 modem = 0; 476 if (notty && log_to_fd <= 1) 477 log_to_fd = -1; 478 } else { 479 /* 480 * If the user has specified a device which is the same as 481 * the one on stdin, pretend they didn't specify any. 482 * If the device is already open read/write on stdin, 483 * we assume we don't need to lock it, and we can open it 484 * as root. 485 */ 486 if (fstat(0, &statbuf) >= 0 && S_ISCHR(statbuf.st_mode) 487 && statbuf.st_rdev == devstat.st_rdev) { 488 default_device = 1; 489 fdflags = fcntl(0, F_GETFL); 490 if (fdflags != -1 && (fdflags & O_ACCMODE) == O_RDWR) 491 privopen = 1; 492 } 493 } 494 if (default_device) 495 nodetach = 1; 496 497 /* 498 * Don't send log messages to the serial port, it tends to 499 * confuse the peer. :-) 500 */ 501 if (log_to_fd >= 0 && fstat(log_to_fd, &statbuf) >= 0 502 && S_ISCHR(statbuf.st_mode) && statbuf.st_rdev == devstat.st_rdev) 503 log_to_fd = -1; 504} 505 506/* 507 * connect_tty - get the serial port ready to start doing PPP. 508 * That is, open the serial port, set its speed and mode, and run 509 * the connector and/or welcomer. 510 */ 511int connect_tty() 512{ 513 char *connector; 514 int fdflags; 515#ifndef __linux__ 516 struct stat statbuf; 517#endif 518 char numbuf[16]; 519 520 /* 521 * Get a pty master/slave pair if the pty, notty, socket, 522 * or record options were specified. 523 */ 524 strlcpy(ppp_devnam, devnam, sizeof(ppp_devnam)); 525 pty_master = -1; 526 pty_slave = -1; 527 real_ttyfd = -1; 528 if (using_pty || record_file != NULL) { 529 if (!get_pty(&pty_master, &pty_slave, ppp_devnam, uid)) { 530 error("Couldn't allocate pseudo-tty"); 531 status = EXIT_FATAL_ERROR; 532 return -1; 533 } 534 set_up_tty(pty_slave, 1); 535 } 536 537 /* 538 * Lock the device if we've been asked to. 539 */ 540 status = EXIT_LOCK_FAILED; 541 if (lockflag && !privopen) { 542 if (lock(devnam) < 0) 543 return -1; 544 locked = 1; 545 } 546 547 /* 548 * Open the serial device and set it up to be the ppp interface. 549 * First we open it in non-blocking mode so we can set the 550 * various termios flags appropriately. If we aren't dialling 551 * out and we want to use the modem lines, we reopen it later 552 * in order to wait for the carrier detect signal from the modem. 553 */ 554 hungup = 0; 555 kill_link = 0; 556 connector = doing_callback? callback_script: connect_script; 557 if (devnam[0] != 0) { 558 for (;;) { 559 /* If the user specified the device name, become the 560 user before opening it. */ 561 int err, prio; 562 563 prio = privopen? OPRIO_ROOT: tty_options[0].priority; 564 if (prio < OPRIO_ROOT) 565 seteuid(uid); 566 ttyfd = open(devnam, O_NONBLOCK | O_RDWR, 0); 567 err = errno; 568 if (prio < OPRIO_ROOT) 569 seteuid(0); 570 if (ttyfd >= 0) 571 break; 572 errno = err; 573 if (err != EINTR) { 574 error("Failed to open %s: %m", devnam); 575 status = EXIT_OPEN_FAILED; 576 } 577 if (!persist || err != EINTR) 578 return -1; 579 } 580 real_ttyfd = ttyfd; 581 if ((fdflags = fcntl(ttyfd, F_GETFL)) == -1 582 || fcntl(ttyfd, F_SETFL, fdflags & ~O_NONBLOCK) < 0) 583 warn("Couldn't reset non-blocking mode on device: %m"); 584 585#ifndef __linux__ 586 /* 587 * Linux 2.4 and above blocks normal writes to the tty 588 * when it is in PPP line discipline, so this isn't needed. 589 */ 590 /* 591 * Do the equivalent of `mesg n' to stop broadcast messages. 592 */ 593 if (fstat(ttyfd, &statbuf) < 0 594 || fchmod(ttyfd, statbuf.st_mode & ~(S_IWGRP | S_IWOTH)) < 0) { 595 warn("Couldn't restrict write permissions to %s: %m", devnam); 596 } else 597 tty_mode = statbuf.st_mode; 598#endif /* __linux__ */ 599 600 /* 601 * Set line speed, flow control, etc. 602 * If we have a non-null connection or initializer script, 603 * on most systems we set CLOCAL for now so that we can talk 604 * to the modem before carrier comes up. But this has the 605 * side effect that we might miss it if CD drops before we 606 * get to clear CLOCAL below. On systems where we can talk 607 * successfully to the modem with CLOCAL clear and CD down, 608 * we could clear CLOCAL at this point. 609 */ 610 set_up_tty(ttyfd, ((connector != NULL && connector[0] != 0) 611 || initializer != NULL)); 612 } 613 614 /* 615 * If the pty, socket, notty and/or record option was specified, 616 * start up the character shunt now. 617 */ 618 status = EXIT_PTYCMD_FAILED; 619 if (ptycommand != NULL) { 620 if (record_file != NULL) { 621 int ipipe[2], opipe[2], ok; 622 623 if (pipe(ipipe) < 0 || pipe(opipe) < 0) 624 fatal("Couldn't create pipes for record option: %m"); 625 626 /* don't leak these to the ptycommand */ 627 (void) fcntl(ipipe[0], F_SETFD, FD_CLOEXEC); 628 (void) fcntl(opipe[1], F_SETFD, FD_CLOEXEC); 629 630 ok = device_script(ptycommand, opipe[0], ipipe[1], 1) == 0 631 && start_charshunt(ipipe[0], opipe[1]); 632 close(ipipe[0]); 633 close(ipipe[1]); 634 close(opipe[0]); 635 close(opipe[1]); 636 if (!ok) 637 return -1; 638 } else { 639 if (device_script(ptycommand, pty_master, pty_master, 1) < 0) 640 return -1; 641 ttyfd = pty_slave; 642 close(pty_master); 643 pty_master = -1; 644 } 645 } else if (pty_socket != NULL) { 646 int fd = open_socket(pty_socket); 647 if (fd < 0) 648 return -1; 649 if (!start_charshunt(fd, fd)) 650 return -1; 651 } else if (notty) { 652 if (!start_charshunt(0, 1)) 653 return -1; 654 } else if (record_file != NULL) { 655 if (!start_charshunt(ttyfd, ttyfd)) 656 return -1; 657 } 658 659 /* run connection script */ 660 if ((connector && connector[0]) || initializer) { 661 if (real_ttyfd != -1) { 662 /* XXX do this if doing_callback == CALLBACK_DIALIN? */ 663 if (!default_device && modem) { 664 setdtr(real_ttyfd, 0); /* in case modem is off hook */ 665 sleep(1); 666 setdtr(real_ttyfd, 1); 667 } 668 } 669 670 if (initializer && initializer[0]) { 671 if (device_script(initializer, ttyfd, ttyfd, 0) < 0) { 672 error("Initializer script failed"); 673 status = EXIT_INIT_FAILED; 674 return -1; 675 } 676 if (kill_link) { 677 disconnect_tty(); 678 return -1; 679 } 680 info("Serial port initialized."); 681 } 682 683 if (connector && connector[0]) { 684 if (device_script(connector, ttyfd, ttyfd, 0) < 0) { 685 error("Connect script failed"); 686 status = EXIT_CONNECT_FAILED; 687 return -1; 688 } 689 if (kill_link) { 690 disconnect_tty(); 691 return -1; 692 } 693 info("Serial connection established."); 694 } 695 696 /* set line speed, flow control, etc.; 697 clear CLOCAL if modem option */ 698 if (real_ttyfd != -1) 699 set_up_tty(real_ttyfd, 0); 700 701 if (doing_callback == CALLBACK_DIALIN) 702 connector = NULL; 703 } 704 705 /* reopen tty if necessary to wait for carrier */ 706 if (connector == NULL && modem && devnam[0] != 0) { 707 int i; 708 for (;;) { 709 if ((i = open(devnam, O_RDWR)) >= 0) 710 break; 711 if (errno != EINTR) { 712 error("Failed to reopen %s: %m", devnam); 713 status = EXIT_OPEN_FAILED; 714 } 715 if (!persist || errno != EINTR || hungup || kill_link) 716 return -1; 717 } 718 close(i); 719 } 720 721 slprintf(numbuf, sizeof(numbuf), "%d", baud_rate); 722 script_setenv("SPEED", numbuf, 0); 723 724 /* run welcome script, if any */ 725 if (welcomer && welcomer[0]) { 726 if (device_script(welcomer, ttyfd, ttyfd, 0) < 0) 727 warn("Welcome script failed"); 728 } 729 730 /* 731 * If we are initiating this connection, wait for a short 732 * time for something from the peer. This can avoid bouncing 733 * our packets off his tty before he has it set up. 734 */ 735 if (connector != NULL || ptycommand != NULL) 736 listen_time = connect_delay; 737 738 return ttyfd; 739} 740 741 742void disconnect_tty() 743{ 744 if (disconnect_script == NULL || hungup) 745 return; 746 if (real_ttyfd >= 0) 747 set_up_tty(real_ttyfd, 1); 748 if (device_script(disconnect_script, ttyfd, ttyfd, 0) < 0) { 749 warn("disconnect script failed"); 750 } else { 751 info("Serial link disconnected."); 752 } 753} 754 755void tty_close_fds() 756{ 757 if (pty_master >= 0) 758 close(pty_master); 759 if (pty_slave >= 0) 760 close(pty_slave); 761 if (real_ttyfd >= 0) { 762 close(real_ttyfd); 763 real_ttyfd = -1; 764 } 765 /* N.B. ttyfd will == either pty_slave or real_ttyfd */ 766} 767 768void cleanup_tty() 769{ 770 if (real_ttyfd >= 0) 771 finish_tty(); 772 tty_close_fds(); 773 if (locked) { 774 unlock(); 775 locked = 0; 776 } 777} 778 779/* 780 * tty_do_send_config - set transmit-side PPP configuration. 781 * We set the extended transmit ACCM here as well. 782 */ 783void 784tty_do_send_config(mtu, accm, pcomp, accomp) 785 int mtu; 786 u_int32_t accm; 787 int pcomp, accomp; 788{ 789 tty_set_xaccm(xmit_accm); 790 tty_send_config(mtu, accm, pcomp, accomp); 791} 792 793/* 794 * finish_tty - restore the terminal device to its original settings 795 */ 796static void 797finish_tty() 798{ 799 /* drop dtr to hang up */ 800 if (!default_device && modem) { 801 setdtr(real_ttyfd, 0); 802 /* 803 * This sleep is in case the serial port has CLOCAL set by default, 804 * and consequently will reassert DTR when we close the device. 805 */ 806 sleep(1); 807 } 808 809 restore_tty(real_ttyfd); 810 811#ifndef __linux__ 812 if (tty_mode != (mode_t) -1) { 813 if (fchmod(real_ttyfd, tty_mode) != 0) { 814 /* XXX if devnam is a symlink, this will change the link */ 815 chmod(devnam, tty_mode); 816 } 817 } 818#endif /* __linux__ */ 819 820 close(real_ttyfd); 821 real_ttyfd = -1; 822} 823 824/* 825 * maybe_relock - our PID has changed, maybe update the lock file. 826 */ 827static void 828maybe_relock(arg, pid) 829 void *arg; 830 int pid; 831{ 832 if (locked) 833 relock(pid); 834} 835 836/* 837 * open_socket - establish a stream socket connection to the nominated 838 * host and port. 839 */ 840static int 841open_socket(dest) 842 char *dest; 843{ 844 char *sep, *endp = NULL; 845 int sock, port = -1; 846 u_int32_t host; 847 struct hostent *hent; 848 struct sockaddr_in sad; 849 850 /* parse host:port and resolve host to an IP address */ 851 sep = strchr(dest, ':'); 852 if (sep != NULL) 853 port = strtol(sep+1, &endp, 10); 854 if (port < 0 || endp == sep+1 || sep == dest) { 855 error("Can't parse host:port for socket destination"); 856 return -1; 857 } 858 *sep = 0; 859 host = inet_addr(dest); 860 if (host == (u_int32_t) -1) { 861 hent = gethostbyname(dest); 862 if (hent == NULL) { 863 error("%s: unknown host in socket option", dest); 864 *sep = ':'; 865 return -1; 866 } 867 host = *(u_int32_t *)(hent->h_addr_list[0]); 868 } 869 *sep = ':'; 870 871 /* get a socket and connect it to the other end */ 872 sock = socket(PF_INET, SOCK_STREAM, 0); 873 if (sock < 0) { 874 error("Can't create socket: %m"); 875 return -1; 876 } 877 memset(&sad, 0, sizeof(sad)); 878 sad.sin_family = AF_INET; 879 sad.sin_port = htons(port); 880 sad.sin_addr.s_addr = host; 881 if (connect(sock, (struct sockaddr *)&sad, sizeof(sad)) < 0) { 882 error("Can't connect to %s: %m", dest); 883 close(sock); 884 return -1; 885 } 886 887 return sock; 888} 889 890 891/* 892 * start_charshunt - create a child process to run the character shunt. 893 */ 894static int 895start_charshunt(ifd, ofd) 896 int ifd, ofd; 897{ 898 int cpid; 899 900 cpid = safe_fork(); 901 if (cpid == -1) { 902 error("Can't fork process for character shunt: %m"); 903 return 0; 904 } 905 if (cpid == 0) { 906 /* child */ 907 close(pty_slave); 908 setuid(uid); 909 if (getuid() != uid) 910 fatal("setuid failed"); 911 setgid(getgid()); 912 if (!nodetach) 913 log_to_fd = -1; 914 charshunt(ifd, ofd, record_file); 915 exit(0); 916 } 917 charshunt_pid = cpid; 918 add_notifier(&sigreceived, stop_charshunt, 0); 919 close(pty_master); 920 pty_master = -1; 921 ttyfd = pty_slave; 922 record_child(cpid, "pppd (charshunt)", charshunt_done, NULL); 923 return 1; 924} 925 926static void 927charshunt_done(arg) 928 void *arg; 929{ 930 charshunt_pid = 0; 931} 932 933static void 934stop_charshunt(arg, sig) 935 void *arg; 936 int sig; 937{ 938 if (charshunt_pid) 939 kill(charshunt_pid, (sig == SIGINT? sig: SIGTERM)); 940} 941 942/* 943 * charshunt - the character shunt, which passes characters between 944 * the pty master side and the serial port (or stdin/stdout). 945 * This runs as the user (not as root). 946 * (We assume ofd >= ifd which is true the way this gets called. :-). 947 */ 948static void 949charshunt(ifd, ofd, record_file) 950 int ifd, ofd; 951 char *record_file; 952{ 953 int n, nfds; 954 fd_set ready, writey; 955 u_char *ibufp, *obufp; 956 int nibuf, nobuf; 957 int flags; 958 int pty_readable, stdin_readable; 959 struct timeval lasttime; 960 FILE *recordf = NULL; 961 int ilevel, olevel, max_level; 962 struct timeval levelt, tout, *top; 963 extern u_char inpacket_buf[]; 964 965 /* 966 * Reset signal handlers. 967 */ 968 signal(SIGHUP, SIG_IGN); /* Hangup */ 969 signal(SIGINT, SIG_DFL); /* Interrupt */ 970 signal(SIGTERM, SIG_DFL); /* Terminate */ 971 signal(SIGCHLD, SIG_DFL); 972 signal(SIGUSR1, SIG_DFL); 973 signal(SIGUSR2, SIG_DFL); 974 signal(SIGABRT, SIG_DFL); 975 signal(SIGALRM, SIG_DFL); 976 signal(SIGFPE, SIG_DFL); 977 signal(SIGILL, SIG_DFL); 978 signal(SIGPIPE, SIG_DFL); 979 signal(SIGQUIT, SIG_DFL); 980 signal(SIGSEGV, SIG_DFL); 981#ifdef SIGBUS 982 signal(SIGBUS, SIG_DFL); 983#endif 984#ifdef SIGEMT 985 signal(SIGEMT, SIG_DFL); 986#endif 987#ifdef SIGPOLL 988 signal(SIGPOLL, SIG_DFL); 989#endif 990#ifdef SIGPROF 991 signal(SIGPROF, SIG_DFL); 992#endif 993#ifdef SIGSYS 994 signal(SIGSYS, SIG_DFL); 995#endif 996#ifdef SIGTRAP 997 signal(SIGTRAP, SIG_DFL); 998#endif 999#ifdef SIGVTALRM 1000 signal(SIGVTALRM, SIG_DFL); 1001#endif 1002#ifdef SIGXCPU 1003 signal(SIGXCPU, SIG_DFL); 1004#endif 1005#ifdef SIGXFSZ 1006 signal(SIGXFSZ, SIG_DFL); 1007#endif 1008 1009 /* 1010 * Check that the fds won't overrun the fd_sets 1011 */ 1012 if (ifd >= FD_SETSIZE || ofd >= FD_SETSIZE || pty_master >= FD_SETSIZE) 1013 fatal("internal error: file descriptor too large (%d, %d, %d)", 1014 ifd, ofd, pty_master); 1015 1016 /* 1017 * Open the record file if required. 1018 */ 1019 if (record_file != NULL) { 1020 recordf = fopen(record_file, "a"); 1021 if (recordf == NULL) 1022 error("Couldn't create record file %s: %m", record_file); 1023 } 1024 1025 /* set all the fds to non-blocking mode */ 1026 flags = fcntl(pty_master, F_GETFL); 1027 if (flags == -1 1028 || fcntl(pty_master, F_SETFL, flags | O_NONBLOCK) == -1) 1029 warn("couldn't set pty master to nonblock: %m"); 1030 flags = fcntl(ifd, F_GETFL); 1031 if (flags == -1 1032 || fcntl(ifd, F_SETFL, flags | O_NONBLOCK) == -1) 1033 warn("couldn't set %s to nonblock: %m", (ifd==0? "stdin": "tty")); 1034 if (ofd != ifd) { 1035 flags = fcntl(ofd, F_GETFL); 1036 if (flags == -1 1037 || fcntl(ofd, F_SETFL, flags | O_NONBLOCK) == -1) 1038 warn("couldn't set stdout to nonblock: %m"); 1039 } 1040 1041 nibuf = nobuf = 0; 1042 ibufp = obufp = NULL; 1043 pty_readable = stdin_readable = 1; 1044 1045 ilevel = olevel = 0; 1046 gettimeofday(&levelt, NULL); 1047 if (max_data_rate) { 1048 max_level = max_data_rate / 10; 1049 if (max_level < 100) 1050 max_level = 100; 1051 } else 1052 max_level = PPP_MRU + PPP_HDRLEN + 1; 1053 1054 nfds = (ofd > pty_master? ofd: pty_master) + 1; 1055 if (recordf != NULL) { 1056 gettimeofday(&lasttime, NULL); 1057 putc(7, recordf); /* put start marker */ 1058 putc(lasttime.tv_sec >> 24, recordf); 1059 putc(lasttime.tv_sec >> 16, recordf); 1060 putc(lasttime.tv_sec >> 8, recordf); 1061 putc(lasttime.tv_sec, recordf); 1062 lasttime.tv_usec = 0; 1063 } 1064 1065 while (nibuf != 0 || nobuf != 0 || pty_readable || stdin_readable) { 1066 top = 0; 1067 tout.tv_sec = 0; 1068 tout.tv_usec = 10000; 1069 FD_ZERO(&ready); 1070 FD_ZERO(&writey); 1071 if (nibuf != 0) { 1072 if (ilevel >= max_level) 1073 top = &tout; 1074 else 1075 FD_SET(pty_master, &writey); 1076 } else if (stdin_readable) 1077 FD_SET(ifd, &ready); 1078 if (nobuf != 0) { 1079 if (olevel >= max_level) 1080 top = &tout; 1081 else 1082 FD_SET(ofd, &writey); 1083 } else if (pty_readable) 1084 FD_SET(pty_master, &ready); 1085 if (select(nfds, &ready, &writey, NULL, top) < 0) { 1086 if (errno != EINTR) 1087 fatal("select"); 1088 continue; 1089 } 1090 if (max_data_rate) { 1091 double dt; 1092 int nbt; 1093 struct timeval now; 1094 1095 gettimeofday(&now, NULL); 1096 dt = (now.tv_sec - levelt.tv_sec 1097 + (now.tv_usec - levelt.tv_usec) / 1e6); 1098 nbt = (int)(dt * max_data_rate); 1099 ilevel = (nbt < 0 || nbt > ilevel)? 0: ilevel - nbt; 1100 olevel = (nbt < 0 || nbt > olevel)? 0: olevel - nbt; 1101 levelt = now; 1102 } else 1103 ilevel = olevel = 0; 1104 if (FD_ISSET(ifd, &ready)) { 1105 ibufp = inpacket_buf; 1106 nibuf = read(ifd, ibufp, PPP_MRU + PPP_HDRLEN); 1107 if (nibuf < 0 && errno == EIO) 1108 nibuf = 0; 1109 if (nibuf < 0) { 1110 if (!(errno == EINTR || errno == EAGAIN)) { 1111 error("Error reading standard input: %m"); 1112 break; 1113 } 1114 nibuf = 0; 1115 } else if (nibuf == 0) { 1116 /* end of file from stdin */ 1117 stdin_readable = 0; 1118 /* do a 0-length write, hopefully this will generate 1119 an EOF (hangup) on the slave side. */ 1120 write(pty_master, inpacket_buf, 0); 1121 if (recordf) 1122 if (!record_write(recordf, 4, NULL, 0, &lasttime)) 1123 recordf = NULL; 1124 } else { 1125 FD_SET(pty_master, &writey); 1126 if (recordf) 1127 if (!record_write(recordf, 2, ibufp, nibuf, &lasttime)) 1128 recordf = NULL; 1129 } 1130 } 1131 if (FD_ISSET(pty_master, &ready)) { 1132 obufp = outpacket_buf; 1133 nobuf = read(pty_master, obufp, PPP_MRU + PPP_HDRLEN); 1134 if (nobuf < 0 && errno == EIO) 1135 nobuf = 0; 1136 if (nobuf < 0) { 1137 if (!(errno == EINTR || errno == EAGAIN)) { 1138 error("Error reading pseudo-tty master: %m"); 1139 break; 1140 } 1141 nobuf = 0; 1142 } else if (nobuf == 0) { 1143 /* end of file from the pty - slave side has closed */ 1144 pty_readable = 0; 1145 stdin_readable = 0; /* pty is not writable now */ 1146 nibuf = 0; 1147 close(ofd); 1148 if (recordf) 1149 if (!record_write(recordf, 3, NULL, 0, &lasttime)) 1150 recordf = NULL; 1151 } else { 1152 FD_SET(ofd, &writey); 1153 if (recordf) 1154 if (!record_write(recordf, 1, obufp, nobuf, &lasttime)) 1155 recordf = NULL; 1156 } 1157 } 1158 if (FD_ISSET(ofd, &writey)) { 1159 n = nobuf; 1160 if (olevel + n > max_level) 1161 n = max_level - olevel; 1162 n = write(ofd, obufp, n); 1163 if (n < 0) { 1164 if (errno == EIO) { 1165 pty_readable = 0; 1166 nobuf = 0; 1167 } else if (errno != EAGAIN && errno != EINTR) { 1168 error("Error writing standard output: %m"); 1169 break; 1170 } 1171 } else { 1172 obufp += n; 1173 nobuf -= n; 1174 olevel += n; 1175 } 1176 } 1177 if (FD_ISSET(pty_master, &writey)) { 1178 n = nibuf; 1179 if (ilevel + n > max_level) 1180 n = max_level - ilevel; 1181 n = write(pty_master, ibufp, n); 1182 if (n < 0) { 1183 if (errno == EIO) { 1184 stdin_readable = 0; 1185 nibuf = 0; 1186 } else if (errno != EAGAIN && errno != EINTR) { 1187 error("Error writing pseudo-tty master: %m"); 1188 break; 1189 } 1190 } else { 1191 ibufp += n; 1192 nibuf -= n; 1193 ilevel += n; 1194 } 1195 } 1196 } 1197 exit(0); 1198} 1199 1200static int 1201record_write(f, code, buf, nb, tp) 1202 FILE *f; 1203 int code; 1204 u_char *buf; 1205 int nb; 1206 struct timeval *tp; 1207{ 1208 struct timeval now; 1209 int diff; 1210 1211 gettimeofday(&now, NULL); 1212 now.tv_usec /= 100000; /* actually 1/10 s, not usec now */ 1213 diff = (now.tv_sec - tp->tv_sec) * 10 + (now.tv_usec - tp->tv_usec); 1214 if (diff > 0) { 1215 if (diff > 255) { 1216 putc(5, f); 1217 putc(diff >> 24, f); 1218 putc(diff >> 16, f); 1219 putc(diff >> 8, f); 1220 putc(diff, f); 1221 } else { 1222 putc(6, f); 1223 putc(diff, f); 1224 } 1225 *tp = now; 1226 } 1227 putc(code, f); 1228 if (buf != NULL) { 1229 putc(nb >> 8, f); 1230 putc(nb, f); 1231 fwrite(buf, nb, 1, f); 1232 } 1233 fflush(f); 1234 if (ferror(f)) { 1235 error("Error writing record file: %m"); 1236 return 0; 1237 } 1238 return 1; 1239} 1240