main.c revision 1.24
1/* $OpenBSD: main.c,v 1.24 1998/07/10 08:06:45 deraadt Exp $ */ 2 3/* 4 * main.c - Point-to-Point Protocol main module 5 * 6 * Copyright (c) 1989 Carnegie Mellon University. 7 * All rights reserved. 8 * 9 * Redistribution and use in source and binary forms are permitted 10 * provided that the above copyright notice and this paragraph are 11 * duplicated in all such forms and that any documentation, 12 * advertising materials, and other materials related to such 13 * distribution and use acknowledge that the software was developed 14 * by Carnegie Mellon University. The name of the 15 * University may not be used to endorse or promote products derived 16 * from this software without specific prior written permission. 17 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR 18 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED 19 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE. 20 */ 21 22#ifndef lint 23#if 0 24static char rcsid[] = "Id: main.c,v 1.49 1998/05/05 05:24:17 paulus Exp $"; 25#else 26static char rcsid[] = "$OpenBSD: main.c,v 1.24 1998/07/10 08:06:45 deraadt Exp $"; 27#endif 28#endif 29 30#include <stdio.h> 31#include <ctype.h> 32#include <stdlib.h> 33#include <string.h> 34#include <unistd.h> 35#include <signal.h> 36#include <errno.h> 37#include <fcntl.h> 38#include <syslog.h> 39#include <netdb.h> 40#include <utmp.h> 41#include <pwd.h> 42#include <sys/param.h> 43#include <sys/types.h> 44#include <sys/wait.h> 45#include <sys/time.h> 46#include <sys/resource.h> 47#include <sys/stat.h> 48#include <sys/socket.h> 49#include <net/if.h> 50 51#include "pppd.h" 52#include "magic.h" 53#include "fsm.h" 54#include "lcp.h" 55#include "ipcp.h" 56#include "upap.h" 57#include "chap.h" 58#include "ccp.h" 59#include "pathnames.h" 60#include "patchlevel.h" 61 62#ifdef CBCP_SUPPORT 63#include "cbcp.h" 64#endif 65 66#if defined(SUNOS4) 67extern char *strerror(); 68#endif 69 70#ifdef IPX_CHANGE 71#include "ipxcp.h" 72#endif /* IPX_CHANGE */ 73#ifdef AT_CHANGE 74#include "atcp.h" 75#endif 76 77/* interface vars */ 78char ifname[IFNAMSIZ]; /* Interface name */ 79int ifunit; /* Interface unit number */ 80 81char *progname; /* Name of this program */ 82char hostname[MAXHOSTNAMELEN]; /* Our hostname */ 83static char pidfilename[MAXPATHLEN]; /* name of pid file */ 84static char default_devnam[MAXPATHLEN]; /* name of default device */ 85static pid_t pid; /* Our pid */ 86static uid_t uid; /* Our real user-id */ 87static int conn_running; /* we have a [dis]connector running */ 88 89int ttyfd = -1; /* Serial port file descriptor */ 90mode_t tty_mode = -1; /* Original access permissions to tty */ 91int baud_rate; /* Actual bits/second for serial device */ 92int hungup; /* terminal has been hung up */ 93int privileged; /* we're running as real uid root */ 94int need_holdoff; /* need holdoff period before restarting */ 95int detached; /* have detached from terminal */ 96 97int phase; /* where the link is at */ 98int kill_link; 99int open_ccp_flag; 100 101char **script_env; /* Env. variable values for scripts */ 102int s_env_nalloc; /* # words avail at script_env */ 103 104u_char outpacket_buf[PPP_MRU+PPP_HDRLEN]; /* buffer for outgoing packet */ 105u_char inpacket_buf[PPP_MRU+PPP_HDRLEN]; /* buffer for incoming packet */ 106 107static int n_children; /* # child processes still running */ 108 109static int locked; /* lock() has succeeded */ 110 111char *no_ppp_msg = "Sorry - this system lacks PPP kernel support\n"; 112 113/* Prototypes for procedures local to this file. */ 114 115static void create_pidfile __P((void)); 116static void cleanup __P((void)); 117static void close_tty __P((void)); 118static void get_input __P((void)); 119static void calltimeout __P((void)); 120static struct timeval *timeleft __P((struct timeval *)); 121static void kill_my_pg __P((int)); 122static void hup __P((int)); 123static void term __P((int)); 124static void chld __P((int)); 125static void toggle_debug __P((int)); 126static void open_ccp __P((int)); 127static void bad_signal __P((int)); 128static void holdoff_end __P((void *)); 129static int device_script __P((char *, int, int)); 130static void reap_kids __P((void)); 131static void pr_log __P((void *, char *, ...)); 132 133extern char *ttyname __P((int)); 134extern char *getlogin __P((void)); 135int main __P((int, char *[])); 136 137#ifdef ultrix 138#undef O_NONBLOCK 139#define O_NONBLOCK O_NDELAY 140#endif 141 142#ifdef ULTRIX 143#define setlogmask(x) 144#endif 145 146/* 147 * PPP Data Link Layer "protocol" table. 148 * One entry per supported protocol. 149 * The last entry must be NULL. 150 */ 151struct protent *protocols[] = { 152 &lcp_protent, 153 &pap_protent, 154 &chap_protent, 155#ifdef CBCP_SUPPORT 156 &cbcp_protent, 157#endif 158 &ipcp_protent, 159 &ccp_protent, 160#ifdef IPX_CHANGE 161 &ipxcp_protent, 162#endif 163#ifdef AT_CHANGE 164 &atcp_protent, 165#endif 166 NULL 167}; 168 169int 170main(argc, argv) 171 int argc; 172 char *argv[]; 173{ 174 int i, fdflags; 175 struct sigaction sa; 176 char *p; 177 struct passwd *pw; 178 struct timeval timo; 179 sigset_t mask; 180 struct protent *protp; 181 struct stat statbuf; 182 char numbuf[16]; 183 184 phase = PHASE_INITIALIZE; 185 p = ttyname(0); 186 if (p) 187 strcpy(devnam, p); 188 strcpy(default_devnam, devnam); 189 190 script_env = NULL; 191 192 /* Initialize syslog facilities */ 193#ifdef ULTRIX 194 openlog("pppd", LOG_PID); 195#else 196 openlog("pppd", LOG_PID | LOG_NDELAY, LOG_PPP); 197 setlogmask(LOG_UPTO(LOG_INFO)); 198#endif 199 200 if (gethostname(hostname, sizeof hostname) < 0 ) { 201 option_error("Couldn't get hostname: %m"); 202 die(1); 203 } 204 205 uid = getuid(); 206 privileged = uid == 0; 207 sprintf(numbuf, "%d", uid); 208 script_setenv("UID", numbuf); 209 210 /* 211 * Initialize to the standard option set, then parse, in order, 212 * the system options file, the user's options file, 213 * the tty's options file, and the command line arguments. 214 */ 215 for (i = 0; (protp = protocols[i]) != NULL; ++i) 216 (*protp->init)(0); 217 218 progname = *argv; 219 220 if (!options_from_file(_PATH_SYSOPTIONS, !privileged, 0, 1) 221 || !options_from_user()) 222 exit(1); 223 scan_args(argc-1, argv+1); /* look for tty name on command line */ 224 if (!options_for_tty() 225 || !parse_args(argc-1, argv+1)) 226 exit(1); 227 228 /* 229 * Check that we are running as root. 230 */ 231 if (geteuid() != 0) { 232 option_error("must be root to run %s, since it is not setuid-root", 233 argv[0]); 234 die(1); 235 } 236 237 if (!ppp_available()) { 238 option_error(no_ppp_msg); 239 exit(1); 240 } 241 242 /* 243 * Check that the options given are valid and consistent. 244 */ 245 sys_check_options(); 246 auth_check_options(); 247 for (i = 0; (protp = protocols[i]) != NULL; ++i) 248 if (protp->check_options != NULL) 249 (*protp->check_options)(); 250 if (demand && connector == 0) { 251 option_error("connect script required for demand-dialling\n"); 252 exit(1); 253 } 254 255 script_setenv("DEVICE", devnam); 256 sprintf(numbuf, "%d", baud_rate); 257 script_setenv("SPEED", numbuf); 258 259 /* 260 * If the user has specified the default device name explicitly, 261 * pretend they hadn't. 262 */ 263 if (!default_device && strcmp(devnam, default_devnam) == 0) 264 default_device = 1; 265 if (default_device) 266 nodetach = 1; 267 268 /* 269 * Initialize system-dependent stuff and magic number package. 270 */ 271 sys_init(); 272 magic_init(); 273 if (debug) 274 setlogmask(LOG_UPTO(LOG_DEBUG)); 275 276 /* 277 * Detach ourselves from the terminal, if required, 278 * and identify who is running us. 279 */ 280 if (nodetach == 0) 281 detach(); 282 pid = getpid(); 283 p = getlogin(); 284 if (p == NULL) { 285 pw = getpwuid(uid); 286 if (pw != NULL && pw->pw_name != NULL) 287 p = pw->pw_name; 288 else 289 p = "(unknown)"; 290 } 291 syslog(LOG_NOTICE, "pppd %s.%d%s started by %s, uid %d", 292 VERSION, PATCHLEVEL, IMPLEMENTATION, p, uid); 293 294 /* 295 * Compute mask of all interesting signals and install signal handlers 296 * for each. Only one signal handler may be active at a time. Therefore, 297 * all other signals should be masked when any handler is executing. 298 */ 299 sigemptyset(&mask); 300 sigaddset(&mask, SIGHUP); 301 sigaddset(&mask, SIGINT); 302 sigaddset(&mask, SIGTERM); 303 sigaddset(&mask, SIGCHLD); 304 305#define SIGNAL(s, handler) { \ 306 sa.sa_handler = handler; \ 307 if (sigaction(s, &sa, NULL) < 0) { \ 308 syslog(LOG_ERR, "Couldn't establish signal handler (%d): %m", s); \ 309 die(1); \ 310 } \ 311 } 312 313 sa.sa_mask = mask; 314 sa.sa_flags = 0; 315 SIGNAL(SIGHUP, hup); /* Hangup */ 316 SIGNAL(SIGINT, term); /* Interrupt */ 317 SIGNAL(SIGTERM, term); /* Terminate */ 318 SIGNAL(SIGCHLD, chld); 319 320 SIGNAL(SIGUSR1, toggle_debug); /* Toggle debug flag */ 321 SIGNAL(SIGUSR2, open_ccp); /* Reopen CCP */ 322 323 /* 324 * Install a handler for other signals which would otherwise 325 * cause pppd to exit without cleaning up. 326 */ 327 SIGNAL(SIGABRT, bad_signal); 328 SIGNAL(SIGALRM, bad_signal); 329 SIGNAL(SIGFPE, bad_signal); 330 SIGNAL(SIGILL, bad_signal); 331 SIGNAL(SIGPIPE, bad_signal); 332 SIGNAL(SIGQUIT, bad_signal); 333 SIGNAL(SIGSEGV, bad_signal); 334#ifdef SIGBUS 335 SIGNAL(SIGBUS, bad_signal); 336#endif 337#ifdef SIGEMT 338 SIGNAL(SIGEMT, bad_signal); 339#endif 340#ifdef SIGPOLL 341 SIGNAL(SIGPOLL, bad_signal); 342#endif 343#ifdef SIGPROF 344 SIGNAL(SIGPROF, bad_signal); 345#endif 346#ifdef SIGSYS 347 SIGNAL(SIGSYS, bad_signal); 348#endif 349#ifdef SIGTRAP 350 SIGNAL(SIGTRAP, bad_signal); 351#endif 352#ifdef SIGVTALRM 353 SIGNAL(SIGVTALRM, bad_signal); 354#endif 355#ifdef SIGXCPU 356 SIGNAL(SIGXCPU, bad_signal); 357#endif 358#ifdef SIGXFSZ 359 SIGNAL(SIGXFSZ, bad_signal); 360#endif 361 362 /* 363 * Apparently we can get a SIGPIPE when we call syslog, if 364 * syslogd has died and been restarted. Ignoring it seems 365 * be sufficient. 366 */ 367 signal(SIGPIPE, SIG_IGN); 368 369 /* 370 * If we're doing dial-on-demand, set up the interface now. 371 */ 372 if (demand) { 373 /* 374 * Open the loopback channel and set it up to be the ppp interface. 375 */ 376 open_ppp_loopback(); 377 378 syslog(LOG_INFO, "Using interface ppp%d", ifunit); 379 (void) sprintf(ifname, "ppp%d", ifunit); 380 script_setenv("IFNAME", ifname); 381 382 create_pidfile(); /* write pid to file */ 383 384 /* 385 * Configure the interface and mark it up, etc. 386 */ 387 demand_conf(); 388 } 389 390 for (;;) { 391 392 need_holdoff = 1; 393 394 if (demand) { 395 /* 396 * Don't do anything until we see some activity. 397 */ 398 phase = PHASE_DORMANT; 399 kill_link = 0; 400 demand_unblock(); 401 for (;;) { 402 wait_loop_output(timeleft(&timo)); 403 calltimeout(); 404 if (kill_link) { 405 if (!persist) 406 die(0); 407 kill_link = 0; 408 } 409 if (get_loop_output()) 410 break; 411 reap_kids(); 412 } 413 414 /* 415 * Now we want to bring up the link. 416 */ 417 demand_block(); 418 syslog(LOG_INFO, "Starting link"); 419 } 420 421 /* 422 * Lock the device if we've been asked to. 423 */ 424 if (lockflag && !default_device) { 425 if (lock(devnam) < 0) 426 goto fail; 427 locked = 1; 428 } 429 430 /* 431 * Open the serial device and set it up to be the ppp interface. 432 * First we open it in non-blocking mode so we can set the 433 * various termios flags appropriately. If we aren't dialling 434 * out and we want to use the modem lines, we reopen it later 435 * in order to wait for the carrier detect signal from the modem. 436 */ 437 while ((ttyfd = open(devnam, O_NONBLOCK | O_RDWR, 0)) < 0) { 438 if (errno != EINTR) 439 syslog(LOG_ERR, "Failed to open %s: %m", devnam); 440 if (!persist || errno != EINTR) 441 goto fail; 442 } 443 if ((fdflags = fcntl(ttyfd, F_GETFL)) == -1 444 || fcntl(ttyfd, F_SETFL, fdflags & ~O_NONBLOCK) < 0) 445 syslog(LOG_WARNING, 446 "Couldn't reset non-blocking mode on device: %m"); 447 448 hungup = 0; 449 kill_link = 0; 450 451 /* 452 * Do the equivalent of `mesg n' to stop broadcast messages. 453 */ 454 if (fstat(ttyfd, &statbuf) < 0 455 || fchmod(ttyfd, statbuf.st_mode & ~(S_IWGRP | S_IWOTH)) < 0) { 456 syslog(LOG_WARNING, 457 "Couldn't restrict write permissions to %s: %m", devnam); 458 } else 459 tty_mode = statbuf.st_mode; 460 461 /* run connection script */ 462 if (connector && connector[0]) { 463 MAINDEBUG((LOG_INFO, "Connecting with <%s>", connector)); 464 465 /* 466 * Set line speed, flow control, etc. 467 * On most systems we set CLOCAL for now so that we can talk 468 * to the modem before carrier comes up. But this has the 469 * side effect that we might miss it if CD drops before we 470 * get to clear CLOCAL below. On systems where we can talk 471 * successfully to the modem with CLOCAL clear and CD down, 472 * we can clear CLOCAL at this point. 473 */ 474 set_up_tty(ttyfd, (modem_chat == 0)); 475 476 /* drop dtr to hang up in case modem is off hook */ 477 if (!default_device && modem) { 478 setdtr(ttyfd, FALSE); 479 sleep(1); 480 setdtr(ttyfd, TRUE); 481 } 482 483 if (device_script(connector, ttyfd, ttyfd) < 0) { 484 syslog(LOG_ERR, "Connect script failed"); 485 setdtr(ttyfd, FALSE); 486 goto fail; 487 } 488 489 syslog(LOG_INFO, "Serial connection established."); 490 sleep(1); /* give it time to set up its terminal */ 491 } 492 493 /* clear CLOCAL if modem option set and we set CLOCAL above */ 494 if (modem && !modem_chat) 495 set_up_tty(ttyfd, 0); 496 497 /* reopen tty if necessary to wait for carrier */ 498 if (connector == NULL && modem) { 499 while ((i = open(devnam, O_RDWR)) < 0) { 500 if (errno != EINTR) 501 syslog(LOG_ERR, "Failed to reopen %s: %m", devnam); 502 if (!persist || errno != EINTR || hungup || kill_link) 503 goto fail; 504 } 505 close(i); 506 } 507 508 /* run welcome script, if any */ 509 if (welcomer && welcomer[0]) { 510 if (device_script(welcomer, ttyfd, ttyfd) < 0) 511 syslog(LOG_WARNING, "Welcome script failed"); 512 } 513 514 /* set up the serial device as a ppp interface */ 515 establish_ppp(ttyfd); 516 517 if (!demand) { 518 519 syslog(LOG_INFO, "Using interface ppp%d", ifunit); 520 (void) sprintf(ifname, "ppp%d", ifunit); 521 script_setenv("IFNAME", ifname); 522 523 create_pidfile(); /* write pid to file */ 524 } 525 526 /* 527 * Start opening the connection and wait for 528 * incoming events (reply, timeout, etc.). 529 */ 530 syslog(LOG_NOTICE, "Connect: %s <--> %s", ifname, devnam); 531 lcp_lowerup(0); 532 lcp_open(0); /* Start protocol */ 533 for (phase = PHASE_ESTABLISH; phase != PHASE_DEAD; ) { 534 wait_input(timeleft(&timo)); 535 calltimeout(); 536 get_input(); 537 if (kill_link) { 538 lcp_close(0, "User request"); 539 kill_link = 0; 540 } 541 if (open_ccp_flag) { 542 if (phase == PHASE_NETWORK) { 543 ccp_fsm[0].flags = OPT_RESTART; /* clears OPT_SILENT */ 544 (*ccp_protent.open)(0); 545 } 546 open_ccp_flag = 0; 547 } 548 reap_kids(); /* Don't leave dead kids lying around */ 549 } 550 551 /* 552 * If we may want to bring the link up again, transfer 553 * the ppp unit back to the loopback. Set the 554 * real serial device back to its normal mode of operation. 555 */ 556 clean_check(); 557 if (demand) 558 restore_loop(); 559 disestablish_ppp(ttyfd); 560 561 /* 562 * Run disconnector script, if requested. 563 * XXX we may not be able to do this if the line has hung up! 564 */ 565 if (disconnector && !hungup) { 566 set_up_tty(ttyfd, 1); 567 if (device_script(disconnector, ttyfd, ttyfd) < 0) { 568 syslog(LOG_WARNING, "disconnect script failed"); 569 } else { 570 syslog(LOG_INFO, "Serial link disconnected."); 571 } 572 } 573 574 fail: 575 if (ttyfd >= 0) 576 close_tty(); 577 if (locked) { 578 unlock(); 579 locked = 0; 580 } 581 582 if (!demand) { 583 if (pidfilename[0] != 0 584 && unlink(pidfilename) < 0 && errno != ENOENT) 585 syslog(LOG_WARNING, "unable to delete pid file: %m"); 586 pidfilename[0] = 0; 587 } 588 589 if (!persist) 590 die(1); 591 592 if (demand) 593 demand_discard(); 594 if (holdoff > 0 && need_holdoff) { 595 phase = PHASE_HOLDOFF; 596 TIMEOUT(holdoff_end, NULL, holdoff); 597 do { 598 wait_time(timeleft(&timo)); 599 calltimeout(); 600 if (kill_link) { 601 if (!persist) 602 die(0); 603 kill_link = 0; 604 phase = PHASE_DORMANT; /* allow signal to end holdoff */ 605 } 606 reap_kids(); 607 } while (phase == PHASE_HOLDOFF); 608 } 609 } 610 611 die(0); 612 return 0; 613} 614 615/* 616 * detach - detach us from the controlling terminal. 617 */ 618void 619detach() 620{ 621 if (detached) 622 return; 623 if (daemon(0, 0) < 0) { 624 perror("Couldn't detach from controlling terminal"); 625 die(1); 626 } 627 detached = 1; 628 pid = getpid(); 629 /* update pid file if it has been written already */ 630 if (pidfilename[0]) 631 create_pidfile(); 632} 633 634/* 635 * Create a file containing our process ID. 636 */ 637static void 638create_pidfile() 639{ 640 FILE *pidfile; 641 642 (void) sprintf(pidfilename, "%s%s.pid", _PATH_VARRUN, ifname); 643 if ((pidfile = fopen(pidfilename, "w")) != NULL) { 644 fprintf(pidfile, "%d\n", pid); 645 (void) fclose(pidfile); 646 } else { 647 syslog(LOG_ERR, "Failed to create pid file %s: %m", pidfilename); 648 pidfilename[0] = 0; 649 } 650} 651 652/* 653 * holdoff_end - called via a timeout when the holdoff period ends. 654 */ 655static void 656holdoff_end(arg) 657 void *arg; 658{ 659 phase = PHASE_DORMANT; 660} 661 662/* 663 * get_input - called when incoming data is available. 664 */ 665static void 666get_input() 667{ 668 int len, i; 669 u_char *p; 670 u_short protocol; 671 struct protent *protp; 672 673 p = inpacket_buf; /* point to beginning of packet buffer */ 674 675 len = read_packet(inpacket_buf); 676 if (len < 0) 677 return; 678 679 if (len == 0) { 680 syslog(LOG_NOTICE, "Modem hangup"); 681 hungup = 1; 682 lcp_lowerdown(0); /* serial link is no longer available */ 683 link_terminated(0); 684 return; 685 } 686 687 if (debug /*&& (debugflags & DBG_INPACKET)*/) 688 log_packet(p, len, "rcvd ", LOG_DEBUG); 689 690 if (len < PPP_HDRLEN) { 691 MAINDEBUG((LOG_INFO, "io(): Received short packet.")); 692 return; 693 } 694 695 p += 2; /* Skip address and control */ 696 GETSHORT(protocol, p); 697 len -= PPP_HDRLEN; 698 699 /* 700 * Toss all non-LCP packets unless LCP is OPEN. 701 */ 702 if (protocol != PPP_LCP && lcp_fsm[0].state != OPENED) { 703 MAINDEBUG((LOG_INFO, 704 "get_input: Received non-LCP packet when LCP not open.")); 705 return; 706 } 707 708 /* 709 * Until we get past the authentication phase, toss all packets 710 * except LCP, LQR and authentication packets. 711 */ 712 if (phase <= PHASE_AUTHENTICATE 713 && !(protocol == PPP_LCP || protocol == PPP_LQR 714 || protocol == PPP_PAP || protocol == PPP_CHAP)) { 715 MAINDEBUG((LOG_INFO, "get_input: discarding proto 0x%x in phase %d", 716 protocol, phase)); 717 return; 718 } 719 720 /* 721 * Upcall the proper protocol input routine. 722 */ 723 for (i = 0; (protp = protocols[i]) != NULL; ++i) { 724 if (protp->protocol == protocol && protp->enabled_flag) { 725 (*protp->input)(0, p, len); 726 return; 727 } 728 if (protocol == (protp->protocol & ~0x8000) && protp->enabled_flag 729 && protp->datainput != NULL) { 730 (*protp->datainput)(0, p, len); 731 return; 732 } 733 } 734 735 if (debug) 736 syslog(LOG_WARNING, "Unsupported protocol (0x%x) received", protocol); 737 lcp_sprotrej(0, p - PPP_HDRLEN, len + PPP_HDRLEN); 738} 739 740 741/* 742 * quit - Clean up state and exit (with an error indication). 743 */ 744void 745quit() 746{ 747 die(1); 748} 749 750/* 751 * die - like quit, except we can specify an exit status. 752 */ 753void 754die(status) 755 int status; 756{ 757 cleanup(); 758 syslog(LOG_INFO, "Exit."); 759 exit(status); 760} 761 762/* 763 * cleanup - restore anything which needs to be restored before we exit 764 */ 765/* ARGSUSED */ 766static void 767cleanup() 768{ 769 sys_cleanup(); 770 771 if (ttyfd >= 0) 772 close_tty(); 773 774 if (pidfilename[0] != 0 && unlink(pidfilename) < 0 && errno != ENOENT) 775 syslog(LOG_WARNING, "unable to delete pid file: %m"); 776 pidfilename[0] = 0; 777 778 if (locked) 779 unlock(); 780} 781 782/* 783 * close_tty - restore the terminal device and close it. 784 */ 785static void 786close_tty() 787{ 788 disestablish_ppp(ttyfd); 789 790 /* drop dtr to hang up */ 791 if (modem) { 792 setdtr(ttyfd, FALSE); 793 /* 794 * This sleep is in case the serial port has CLOCAL set by default, 795 * and consequently will reassert DTR when we close the device. 796 */ 797 sleep(1); 798 } 799 800 restore_tty(ttyfd); 801 802 if (tty_mode != (mode_t) -1) 803 chmod(devnam, tty_mode); 804 805 close(ttyfd); 806 ttyfd = -1; 807} 808 809 810struct callout { 811 struct timeval c_time; /* time at which to call routine */ 812 void *c_arg; /* argument to routine */ 813 void (*c_func) __P((void *)); /* routine */ 814 struct callout *c_next; 815}; 816 817static struct callout *callout = NULL; /* Callout list */ 818static struct timeval timenow; /* Current time */ 819 820/* 821 * timeout - Schedule a timeout. 822 * 823 * Note that this timeout takes the number of seconds, NOT hz (as in 824 * the kernel). 825 */ 826void 827timeout(func, arg, time) 828 void (*func) __P((void *)); 829 void *arg; 830 int time; 831{ 832 struct callout *newp, *p, **pp; 833 834 MAINDEBUG((LOG_DEBUG, "Timeout %lx:%lx in %d seconds.", 835 (long) func, (long) arg, time)); 836 837 /* 838 * Allocate timeout. 839 */ 840 if ((newp = (struct callout *) malloc(sizeof(struct callout))) == NULL) { 841 syslog(LOG_ERR, "Out of memory in timeout()!"); 842 die(1); 843 } 844 newp->c_arg = arg; 845 newp->c_func = func; 846 gettimeofday(&timenow, NULL); 847 newp->c_time.tv_sec = timenow.tv_sec + time; 848 newp->c_time.tv_usec = timenow.tv_usec; 849 850 /* 851 * Find correct place and link it in. 852 */ 853 for (pp = &callout; (p = *pp); pp = &p->c_next) 854 if (newp->c_time.tv_sec < p->c_time.tv_sec 855 || (newp->c_time.tv_sec == p->c_time.tv_sec 856 && newp->c_time.tv_usec < p->c_time.tv_sec)) 857 break; 858 newp->c_next = p; 859 *pp = newp; 860} 861 862 863/* 864 * untimeout - Unschedule a timeout. 865 */ 866void 867untimeout(func, arg) 868 void (*func) __P((void *)); 869 void *arg; 870{ 871 struct callout **copp, *freep; 872 873 MAINDEBUG((LOG_DEBUG, "Untimeout %lx:%lx.", (long) func, (long) arg)); 874 875 /* 876 * Find first matching timeout and remove it from the list. 877 */ 878 for (copp = &callout; (freep = *copp); copp = &freep->c_next) 879 if (freep->c_func == func && freep->c_arg == arg) { 880 *copp = freep->c_next; 881 (void) free((char *) freep); 882 break; 883 } 884} 885 886 887/* 888 * calltimeout - Call any timeout routines which are now due. 889 */ 890static void 891calltimeout() 892{ 893 struct callout *p; 894 895 while (callout != NULL) { 896 p = callout; 897 898 if (gettimeofday(&timenow, NULL) < 0) { 899 syslog(LOG_ERR, "Failed to get time of day: %m"); 900 die(1); 901 } 902 if (!(p->c_time.tv_sec < timenow.tv_sec 903 || (p->c_time.tv_sec == timenow.tv_sec 904 && p->c_time.tv_usec <= timenow.tv_usec))) 905 break; /* no, it's not time yet */ 906 907 callout = p->c_next; 908 (*p->c_func)(p->c_arg); 909 910 free((char *) p); 911 } 912} 913 914 915/* 916 * timeleft - return the length of time until the next timeout is due. 917 */ 918static struct timeval * 919timeleft(tvp) 920 struct timeval *tvp; 921{ 922 if (callout == NULL) 923 return NULL; 924 925 gettimeofday(&timenow, NULL); 926 tvp->tv_sec = callout->c_time.tv_sec - timenow.tv_sec; 927 tvp->tv_usec = callout->c_time.tv_usec - timenow.tv_usec; 928 if (tvp->tv_usec < 0) { 929 tvp->tv_usec += 1000000; 930 tvp->tv_sec -= 1; 931 } 932 if (tvp->tv_sec < 0) 933 tvp->tv_sec = tvp->tv_usec = 0; 934 935 return tvp; 936} 937 938 939/* 940 * kill_my_pg - send a signal to our process group, and ignore it ourselves. 941 */ 942static void 943kill_my_pg(sig) 944 int sig; 945{ 946 struct sigaction act, oldact; 947 948 act.sa_handler = SIG_IGN; 949 act.sa_flags = 0; 950 kill(0, sig); 951 sigaction(sig, &act, &oldact); 952 sigaction(sig, &oldact, NULL); 953} 954 955 956/* 957 * hup - Catch SIGHUP signal. 958 * 959 * Indicates that the physical layer has been disconnected. 960 * We don't rely on this indication; if the user has sent this 961 * signal, we just take the link down. 962 */ 963static void 964hup(sig) 965 int sig; 966{ 967 syslog(LOG_INFO, "Hangup (SIGHUP)"); 968 kill_link = 1; 969 if (conn_running) 970 /* Send the signal to the [dis]connector process(es) also */ 971 kill_my_pg(sig); 972} 973 974 975/* 976 * term - Catch SIGTERM signal and SIGINT signal (^C/del). 977 * 978 * Indicates that we should initiate a graceful disconnect and exit. 979 */ 980/*ARGSUSED*/ 981static void 982term(sig) 983 int sig; 984{ 985 syslog(LOG_INFO, "Terminating on signal %d.", sig); 986 persist = 0; /* don't try to restart */ 987 kill_link = 1; 988 if (conn_running) 989 /* Send the signal to the [dis]connector process(es) also */ 990 kill_my_pg(sig); 991} 992 993 994/* 995 * chld - Catch SIGCHLD signal. 996 * Calls reap_kids to get status for any dead kids. 997 */ 998static void 999chld(sig) 1000 int sig; 1001{ 1002 int save_errno = errno; 1003 1004 reap_kids(); 1005 errno = save_errno; 1006} 1007 1008 1009/* 1010 * toggle_debug - Catch SIGUSR1 signal. 1011 * 1012 * Toggle debug flag. 1013 */ 1014/*ARGSUSED*/ 1015static void 1016toggle_debug(sig) 1017 int sig; 1018{ 1019 debug = !debug; 1020 if (debug) { 1021 setlogmask(LOG_UPTO(LOG_DEBUG)); 1022 } else { 1023 setlogmask(LOG_UPTO(LOG_WARNING)); 1024 } 1025} 1026 1027 1028/* 1029 * open_ccp - Catch SIGUSR2 signal. 1030 * 1031 * Try to (re)negotiate compression. 1032 */ 1033/*ARGSUSED*/ 1034static void 1035open_ccp(sig) 1036 int sig; 1037{ 1038 open_ccp_flag = 1; 1039} 1040 1041 1042/* 1043 * bad_signal - We've caught a fatal signal. Clean up state and exit. 1044 */ 1045static void 1046bad_signal(sig) 1047 int sig; 1048{ 1049 static int crashed = 0; 1050 1051 if (crashed) 1052 _exit(127); 1053 crashed = 1; 1054 syslog(LOG_ERR, "Fatal signal %d", sig); 1055 if (conn_running) 1056 kill_my_pg(SIGTERM); 1057 die(1); 1058} 1059 1060 1061/* 1062 * device_script - run a program to connect or disconnect the 1063 * serial device. 1064 */ 1065static int 1066device_script(program, in, out) 1067 char *program; 1068 int in, out; 1069{ 1070 int pid; 1071 int status; 1072 int errfd; 1073 1074 conn_running = 1; 1075 pid = fork(); 1076 1077 if (pid < 0) { 1078 conn_running = 0; 1079 syslog(LOG_ERR, "Failed to create child process: %m"); 1080 die(1); 1081 } 1082 1083 if (pid == 0) { 1084 sys_close(); 1085 closelog(); 1086 if (in == out) { 1087 if (in != 0) { 1088 dup2(in, 0); 1089 close(in); 1090 } 1091 dup2(0, 1); 1092 } else { 1093 if (out == 0) 1094 out = dup(out); 1095 if (in != 0) { 1096 dup2(in, 0); 1097 close(in); 1098 } 1099 if (out != 1) { 1100 dup2(out, 1); 1101 close(out); 1102 } 1103 } 1104 if (nodetach == 0) { 1105 close(2); 1106 errfd = open(_PATH_CONNERRS, O_WRONLY | O_APPEND | O_CREAT, 0600); 1107 if (errfd >= 0 && errfd != 2) { 1108 dup2(errfd, 2); 1109 close(errfd); 1110 } 1111 } 1112 /* revoke privs */ 1113 seteuid(getuid()); 1114 setuid(getuid()); 1115 setegid(getgid()); 1116 setgid(getgid()); 1117 execl("/bin/sh", "sh", "-c", program, (char *)0); 1118 syslog(LOG_ERR, "could not exec /bin/sh: %m"); 1119 _exit(99); 1120 /* NOTREACHED */ 1121 } 1122 1123 while (waitpid(pid, &status, 0) < 0) { 1124 if (errno == EINTR) 1125 continue; 1126 syslog(LOG_ERR, "error waiting for (dis)connection process: %m"); 1127 die(1); 1128 } 1129 conn_running = 0; 1130 1131 return (status == 0 ? 0 : -1); 1132} 1133 1134 1135/* 1136 * run-program - execute a program with given arguments, 1137 * but don't wait for it. 1138 * If the program can't be executed, logs an error unless 1139 * must_exist is 0 and the program file doesn't exist. 1140 */ 1141int 1142run_program(prog, args, must_exist) 1143 char *prog; 1144 char **args; 1145 int must_exist; 1146{ 1147 int pid; 1148 1149 pid = fork(); 1150 if (pid == -1) { 1151 syslog(LOG_ERR, "Failed to create child process for %s: %m", prog); 1152 return -1; 1153 } 1154 if (pid == 0) { 1155 int new_fd; 1156 1157 /* Leave the current location */ 1158 (void) setsid(); /* No controlling tty. */ 1159 (void) umask (S_IRWXG|S_IRWXO); 1160 (void) chdir ("/"); /* no current directory. */ 1161 setuid(geteuid()); 1162 setgid(getegid()); 1163 1164 /* Ensure that nothing of our device environment is inherited. */ 1165 sys_close(); 1166 closelog(); 1167 close (0); 1168 close (1); 1169 close (2); 1170 close (ttyfd); /* tty interface to the ppp device */ 1171 1172 /* Don't pass handles to the PPP device, even by accident. */ 1173 new_fd = open (_PATH_DEVNULL, O_RDWR); 1174 if (new_fd >= 0) { 1175 if (new_fd != 0) { 1176 dup2 (new_fd, 0); /* stdin <- /dev/null */ 1177 close (new_fd); 1178 } 1179 dup2 (0, 1); /* stdout -> /dev/null */ 1180 dup2 (0, 2); /* stderr -> /dev/null */ 1181 } 1182 1183#ifdef BSD 1184 /* Force the priority back to zero if pppd is running higher. */ 1185 if (setpriority (PRIO_PROCESS, 0, 0) < 0) 1186 syslog (LOG_WARNING, "can't reset priority to 0: %m"); 1187#endif 1188 1189 /* SysV recommends a second fork at this point. */ 1190 1191 /* run the program; give it a null environment */ 1192 execve(prog, args, script_env); 1193 if (must_exist || errno != ENOENT) 1194 syslog(LOG_WARNING, "Can't execute %s: %m", prog); 1195 _exit(-1); 1196 } 1197 MAINDEBUG((LOG_DEBUG, "Script %s started; pid = %d", prog, pid)); 1198 ++n_children; 1199 return 0; 1200} 1201 1202 1203/* 1204 * reap_kids - get status from any dead child processes, 1205 * and log a message for abnormal terminations. 1206 */ 1207static void 1208reap_kids() 1209{ 1210 int pid, status; 1211 1212 if (n_children == 0) 1213 return; 1214 if ((pid = waitpid(-1, &status, WNOHANG)) == -1) { 1215 if (errno != ECHILD) 1216 syslog(LOG_ERR, "Error waiting for child process: %m"); 1217 return; 1218 } 1219 if (pid > 0) { 1220 --n_children; 1221 if (WIFSIGNALED(status)) { 1222 syslog(LOG_WARNING, "Child process %d terminated with signal %d", 1223 pid, WTERMSIG(status)); 1224 } 1225 } 1226} 1227 1228 1229/* 1230 * log_packet - format a packet and log it. 1231 */ 1232 1233char line[256]; /* line to be logged accumulated here */ 1234char *linep; 1235 1236void 1237log_packet(p, len, prefix, level) 1238 u_char *p; 1239 int len; 1240 char *prefix; 1241 int level; 1242{ 1243 strcpy(line, prefix); 1244 linep = line + strlen(line); 1245 format_packet(p, len, pr_log, NULL); 1246 if (linep != line) 1247 syslog(level, "%s", line); 1248} 1249 1250/* 1251 * format_packet - make a readable representation of a packet, 1252 * calling `printer(arg, format, ...)' to output it. 1253 */ 1254void 1255format_packet(p, len, printer, arg) 1256 u_char *p; 1257 int len; 1258 void (*printer) __P((void *, char *, ...)); 1259 void *arg; 1260{ 1261 int i, n; 1262 u_short proto; 1263 u_char x; 1264 struct protent *protp; 1265 1266 if (len >= PPP_HDRLEN && p[0] == PPP_ALLSTATIONS && p[1] == PPP_UI) { 1267 p += 2; 1268 GETSHORT(proto, p); 1269 len -= PPP_HDRLEN; 1270 for (i = 0; (protp = protocols[i]) != NULL; ++i) 1271 if (proto == protp->protocol) 1272 break; 1273 if (protp != NULL) { 1274 printer(arg, "[%s", protp->name); 1275 n = (*protp->printpkt)(p, len, printer, arg); 1276 printer(arg, "]"); 1277 p += n; 1278 len -= n; 1279 } else { 1280 printer(arg, "[proto=0x%x]", proto); 1281 } 1282 } 1283 1284 for (; len > 0; --len) { 1285 GETCHAR(x, p); 1286 printer(arg, " %.2x", x); 1287 } 1288} 1289 1290static void 1291pr_log __V((void *arg, char *fmt, ...)) 1292{ 1293 int n; 1294 va_list pvar; 1295 char buf[256]; 1296 1297#ifdef __STDC__ 1298 va_start(pvar, fmt); 1299#else 1300 void *arg; 1301 char *fmt; 1302 va_start(pvar); 1303 arg = va_arg(pvar, void *); 1304 fmt = va_arg(pvar, char *); 1305#endif 1306 1307 n = vfmtmsg(buf, sizeof(buf), fmt, pvar); 1308 va_end(pvar); 1309 1310 if (linep + n + 1 > line + sizeof(line)) { 1311 syslog(LOG_DEBUG, "%s", line); 1312 linep = line; 1313 } 1314 strcpy(linep, buf); 1315 linep += n; 1316} 1317 1318/* 1319 * print_string - print a readable representation of a string using 1320 * printer. 1321 */ 1322void 1323print_string(p, len, printer, arg) 1324 char *p; 1325 int len; 1326 void (*printer) __P((void *, char *, ...)); 1327 void *arg; 1328{ 1329 int c; 1330 1331 printer(arg, "\""); 1332 for (; len > 0; --len) { 1333 c = *p++; 1334 if (' ' <= c && c <= '~') { 1335 if (c == '\\' || c == '"') 1336 printer(arg, "\\"); 1337 printer(arg, "%c", c); 1338 } else { 1339 switch (c) { 1340 case '\n': 1341 printer(arg, "\\n"); 1342 break; 1343 case '\r': 1344 printer(arg, "\\r"); 1345 break; 1346 case '\t': 1347 printer(arg, "\\t"); 1348 break; 1349 default: 1350 printer(arg, "\\%.3o", c); 1351 } 1352 } 1353 } 1354 printer(arg, "\""); 1355} 1356 1357/* 1358 * novm - log an error message saying we ran out of memory, and die. 1359 */ 1360void 1361novm(msg) 1362 char *msg; 1363{ 1364 syslog(LOG_ERR, "Virtual memory exhausted allocating %s", msg); 1365 die(1); 1366} 1367 1368/* 1369 * fmtmsg - format a message into a buffer. Like sprintf except we 1370 * also specify the length of the output buffer, and we handle 1371 * %r (recursive format), %m (error message) and %I (IP address) formats. 1372 * Doesn't do floating-point formats. 1373 * Returns the number of chars put into buf. 1374 */ 1375int 1376fmtmsg __V((char *buf, int buflen, char *fmt, ...)) 1377{ 1378 va_list args; 1379 int n; 1380 1381#ifdef __STDC__ 1382 va_start(args, fmt); 1383#else 1384 char *buf; 1385 int buflen; 1386 char *fmt; 1387 va_start(args); 1388 buf = va_arg(args, char *); 1389 buflen = va_arg(args, int); 1390 fmt = va_arg(args, char *); 1391#endif 1392 n = vfmtmsg(buf, buflen, fmt, args); 1393 va_end(args); 1394 return n; 1395} 1396 1397/* 1398 * vfmtmsg - like fmtmsg, takes a va_list instead of a list of args. 1399 */ 1400#define OUTCHAR(c) (buflen > 0? (--buflen, *buf++ = (c)): 0) 1401 1402int 1403vfmtmsg(buf, buflen, fmt, args) 1404 char *buf; 1405 int buflen; 1406 char *fmt; 1407 va_list args; 1408{ 1409 int c, i, n; 1410 int width, prec, fillch; 1411 int base, len, neg, quoted; 1412 unsigned long val = 0; 1413 char *str, *f, *buf0; 1414 unsigned char *p; 1415 char num[32]; 1416 time_t t; 1417 static char hexchars[] = "0123456789abcdef"; 1418 1419 buf0 = buf; 1420 --buflen; 1421 while (buflen > 0) { 1422 for (f = fmt; *f != '%' && *f != 0; ++f) 1423 ; 1424 if (f > fmt) { 1425 len = f - fmt; 1426 if (len > buflen) 1427 len = buflen; 1428 memcpy(buf, fmt, len); 1429 buf += len; 1430 buflen -= len; 1431 fmt = f; 1432 } 1433 if (*fmt == 0) 1434 break; 1435 c = *++fmt; 1436 width = prec = 0; 1437 fillch = ' '; 1438 if (c == '0') { 1439 fillch = '0'; 1440 c = *++fmt; 1441 } 1442 if (c == '*') { 1443 width = va_arg(args, int); 1444 c = *++fmt; 1445 } else { 1446 while (isdigit(c)) { 1447 width = width * 10 + c - '0'; 1448 c = *++fmt; 1449 } 1450 } 1451 if (c == '.') { 1452 c = *++fmt; 1453 if (c == '*') { 1454 prec = va_arg(args, int); 1455 c = *++fmt; 1456 } else { 1457 while (isdigit(c)) { 1458 prec = prec * 10 + c - '0'; 1459 c = *++fmt; 1460 } 1461 } 1462 } 1463 str = 0; 1464 base = 0; 1465 neg = 0; 1466 ++fmt; 1467 switch (c) { 1468 case 'd': 1469 i = va_arg(args, int); 1470 if (i < 0) { 1471 neg = 1; 1472 val = -i; 1473 } else 1474 val = i; 1475 base = 10; 1476 break; 1477 case 'o': 1478 val = va_arg(args, unsigned int); 1479 base = 8; 1480 break; 1481 case 'x': 1482 val = va_arg(args, unsigned int); 1483 base = 16; 1484 break; 1485 case 'p': 1486 val = (unsigned long) va_arg(args, void *); 1487 base = 16; 1488 neg = 2; 1489 break; 1490 case 's': 1491 str = va_arg(args, char *); 1492 break; 1493 case 'c': 1494 num[0] = va_arg(args, int); 1495 num[1] = 0; 1496 str = num; 1497 break; 1498 case 'm': 1499 str = strerror(errno); 1500 break; 1501 case 'I': 1502 str = ip_ntoa(va_arg(args, u_int32_t)); 1503 break; 1504 case 'r': 1505 f = va_arg(args, char *); 1506#ifndef __powerpc__ 1507 n = vfmtmsg(buf, buflen + 1, f, va_arg(args, va_list)); 1508#else 1509 /* On the powerpc, a va_list is an array of 1 structure */ 1510 n = vfmtmsg(buf, buflen + 1, f, va_arg(args, void *)); 1511#endif 1512 buf += n; 1513 buflen -= n; 1514 continue; 1515 case 't': 1516 time(&t); 1517 str = ctime(&t); 1518 str += 4; /* chop off the day name */ 1519 str[15] = 0; /* chop off year and newline */ 1520 break; 1521 case 'v': /* "visible" string */ 1522 case 'q': /* quoted string */ 1523 quoted = c == 'q'; 1524 p = va_arg(args, unsigned char *); 1525 if (fillch == '0' && prec > 0) { 1526 n = prec; 1527 } else { 1528 n = strlen((char *)p); 1529 if (prec > 0 && prec < n) 1530 n = prec; 1531 } 1532 while (n > 0 && buflen > 0) { 1533 c = *p++; 1534 --n; 1535 if (!quoted && c >= 0x80) { 1536 OUTCHAR('M'); 1537 OUTCHAR('-'); 1538 c -= 0x80; 1539 } 1540 if (quoted && (c == '"' || c == '\\')) 1541 OUTCHAR('\\'); 1542 if (c < 0x20 || (0x7f <= c && c < 0xa0)) { 1543 if (quoted) { 1544 OUTCHAR('\\'); 1545 switch (c) { 1546 case '\t': OUTCHAR('t'); break; 1547 case '\n': OUTCHAR('n'); break; 1548 case '\b': OUTCHAR('b'); break; 1549 case '\f': OUTCHAR('f'); break; 1550 default: 1551 OUTCHAR('x'); 1552 OUTCHAR(hexchars[c >> 4]); 1553 OUTCHAR(hexchars[c & 0xf]); 1554 } 1555 } else { 1556 if (c == '\t') 1557 OUTCHAR(c); 1558 else { 1559 OUTCHAR('^'); 1560 OUTCHAR(c ^ 0x40); 1561 } 1562 } 1563 } else 1564 OUTCHAR(c); 1565 } 1566 continue; 1567 default: 1568 *buf++ = '%'; 1569 if (c != '%') 1570 --fmt; /* so %z outputs %z etc. */ 1571 --buflen; 1572 continue; 1573 } 1574 if (base != 0) { 1575 str = num + sizeof(num); 1576 *--str = 0; 1577 while (str > num + neg) { 1578 *--str = hexchars[val % base]; 1579 val = val / base; 1580 if (--prec <= 0 && val == 0) 1581 break; 1582 } 1583 switch (neg) { 1584 case 1: 1585 *--str = '-'; 1586 break; 1587 case 2: 1588 *--str = 'x'; 1589 *--str = '0'; 1590 break; 1591 } 1592 len = num + sizeof(num) - 1 - str; 1593 } else { 1594 len = strlen(str); 1595 if (prec > 0 && len > prec) 1596 len = prec; 1597 } 1598 if (width > 0) { 1599 if (width > buflen) 1600 width = buflen; 1601 if ((n = width - len) > 0) { 1602 buflen -= n; 1603 for (; n > 0; --n) 1604 *buf++ = fillch; 1605 } 1606 } 1607 if (len > buflen) 1608 len = buflen; 1609 memcpy(buf, str, len); 1610 buf += len; 1611 buflen -= len; 1612 } 1613 *buf = 0; 1614 return buf - buf0; 1615} 1616 1617/* 1618 * script_setenv - set an environment variable value to be used 1619 * for scripts that we run (e.g. ip-up, auth-up, etc.) 1620 */ 1621void 1622script_setenv(var, value) 1623 char *var, *value; 1624{ 1625 int vl = strlen(var); 1626 int i; 1627 char *p, *newstring; 1628 1629 newstring = (char *) malloc(vl + strlen(value) + 2); 1630 if (newstring == 0) 1631 return; 1632 strcpy(newstring, var); 1633 newstring[vl] = '='; 1634 strcpy(newstring+vl+1, value); 1635 1636 /* check if this variable is already set */ 1637 if (script_env != 0) { 1638 for (i = 0; (p = script_env[i]) != 0; ++i) { 1639 if (strncmp(p, var, vl) == 0 && p[vl] == '=') { 1640 free(p); 1641 script_env[i] = newstring; 1642 return; 1643 } 1644 } 1645 } else { 1646 i = 0; 1647 script_env = (char **) malloc(16 * sizeof(char *)); 1648 if (script_env == 0) 1649 return; 1650 s_env_nalloc = 16; 1651 } 1652 1653 /* reallocate script_env with more space if needed */ 1654 if (i + 1 >= s_env_nalloc) { 1655 int new_n = i + 17; 1656 char **newenv = (char **) realloc((void *)script_env, 1657 new_n * sizeof(char *)); 1658 if (newenv == 0) 1659 return; 1660 script_env = newenv; 1661 s_env_nalloc = new_n; 1662 } 1663 1664 script_env[i] = newstring; 1665 script_env[i+1] = 0; 1666} 1667 1668/* 1669 * script_unsetenv - remove a variable from the environment 1670 * for scripts. 1671 */ 1672void 1673script_unsetenv(var) 1674 char *var; 1675{ 1676 int vl = strlen(var); 1677 int i; 1678 char *p; 1679 1680 if (script_env == 0) 1681 return; 1682 for (i = 0; (p = script_env[i]) != 0; ++i) { 1683 if (strncmp(p, var, vl) == 0 && p[vl] == '=') { 1684 free(p); 1685 while ((script_env[i] = script_env[i+1]) != 0) 1686 ++i; 1687 break; 1688 } 1689 } 1690} 1691