1/* 2 * main.c - Point-to-Point Protocol main module 3 * 4 * Copyright (c) 1984-2000 Carnegie Mellon University. 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 "Carnegie Mellon University" must not be used to 19 * endorse or promote products derived from this software without 20 * prior written permission. For permission or any legal 21 * details, please contact 22 * Office of Technology Transfer 23 * Carnegie Mellon University 24 * 5000 Forbes Avenue 25 * Pittsburgh, PA 15213-3890 26 * (412) 268-4387, fax: (412) 268-7395 27 * tech-transfer@andrew.cmu.edu 28 * 29 * 4. Redistributions of any form whatsoever must retain the following 30 * acknowledgment: 31 * "This product includes software developed by Computing Services 32 * at Carnegie Mellon University (http://www.cmu.edu/computing/)." 33 * 34 * CARNEGIE MELLON UNIVERSITY DISCLAIMS ALL WARRANTIES WITH REGARD TO 35 * THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY 36 * AND FITNESS, IN NO EVENT SHALL CARNEGIE MELLON UNIVERSITY BE LIABLE 37 * FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 38 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN 39 * AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING 40 * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 41 */ 42 43#define RCSID "$Id: main.c,v 1.1.1.1 2008/10/15 03:30:46 james26_jang Exp $" 44 45#include <stdio.h> 46#include <ctype.h> 47#include <stdlib.h> 48#include <string.h> 49#include <unistd.h> 50#include <signal.h> 51#include <errno.h> 52#include <fcntl.h> 53#include <syslog.h> 54#include <netdb.h> 55#include <utmp.h> 56#include <pwd.h> 57#include <setjmp.h> 58#include <sys/param.h> 59#include <sys/types.h> 60#include <sys/wait.h> 61#include <sys/time.h> 62#include <sys/resource.h> 63#include <sys/stat.h> 64#include <sys/socket.h> 65#include <netinet/in.h> 66#include <arpa/inet.h> 67 68#include "pppd.h" 69#include "magic.h" 70#include "fsm.h" 71#include "lcp.h" 72#include "ipcp.h" 73#ifdef INET6 74#include "ipv6cp.h" 75#endif 76#include "upap.h" 77#include "chap-new.h" 78#include "eap.h" 79#include "ccp.h" 80#include "ecp.h" 81#include "pathnames.h" 82 83#ifdef USE_TDB 84#include "tdb.h" 85#endif 86 87#ifdef CBCP_SUPPORT 88#include "cbcp.h" 89#endif 90 91#ifdef IPX_CHANGE 92#include "ipxcp.h" 93#endif /* IPX_CHANGE */ 94#ifdef AT_CHANGE 95#include "atcp.h" 96#endif 97 98static const char rcsid[] = RCSID; 99 100/* interface vars */ 101char ifname[32]; /* Interface name */ 102int ifunit; /* Interface unit number */ 103 104struct channel *the_channel; 105 106char *progname; /* Name of this program */ 107char hostname[MAXNAMELEN]; /* Our hostname */ 108static char pidfilename[MAXPATHLEN]; /* name of pid file */ 109static char linkpidfile[MAXPATHLEN]; /* name of linkname pid file */ 110char ppp_devnam[MAXPATHLEN]; /* name of PPP tty (maybe ttypx) */ 111uid_t uid; /* Our real user-id */ 112struct notifier *pidchange = NULL; 113struct notifier *phasechange = NULL; 114struct notifier *exitnotify = NULL; 115struct notifier *sigreceived = NULL; 116struct notifier *fork_notifier = NULL; 117 118int hungup; /* terminal has been hung up */ 119int privileged; /* we're running as real uid root */ 120int need_holdoff; /* need holdoff period before restarting */ 121int detached; /* have detached from terminal */ 122volatile int status; /* exit status for pppd */ 123int unsuccess; /* # unsuccessful connection attempts */ 124int do_callback; /* != 0 if we should do callback next */ 125int doing_callback; /* != 0 if we are doing callback */ 126int ppp_session_number; /* Session number, for channels with such a 127 concept (eg PPPoE) */ 128#ifdef USE_TDB 129TDB_CONTEXT *pppdb; /* database for storing status etc. */ 130#endif 131 132char db_key[32]; 133 134int (*holdoff_hook) __P((void)) = NULL; 135int (*new_phase_hook) __P((int)) = NULL; 136void (*snoop_recv_hook) __P((unsigned char *p, int len)) = NULL; 137void (*snoop_send_hook) __P((unsigned char *p, int len)) = NULL; 138 139static int conn_running; /* we have a [dis]connector running */ 140static int devfd; /* fd of underlying device */ 141static int fd_ppp = -1; /* fd for talking PPP */ 142static int fd_loop; /* fd for getting demand-dial packets */ 143static int fd_devnull; /* fd for /dev/null */ 144 145int phase; /* where the link is at */ 146int kill_link; 147int open_ccp_flag; 148int listen_time; 149int got_sigusr2; 150int got_sigterm; 151int got_sighup; 152 153static int waiting; 154static sigjmp_buf sigjmp; 155 156char **script_env; /* Env. variable values for scripts */ 157int s_env_nalloc; /* # words avail at script_env */ 158 159u_char outpacket_buf[PPP_MRU+PPP_HDRLEN]; /* buffer for outgoing packet */ 160u_char inpacket_buf[PPP_MRU+PPP_HDRLEN]; /* buffer for incoming packet */ 161 162static int n_children; /* # child processes still running */ 163static int got_sigchld; /* set if we have received a SIGCHLD */ 164 165int privopen; /* don't lock, open device as root */ 166 167char *no_ppp_msg = "Sorry - this system lacks PPP kernel support\n"; 168 169GIDSET_TYPE groups[NGROUPS_MAX];/* groups the user is in */ 170int ngroups; /* How many groups valid in groups */ 171 172static struct timeval start_time; /* Time when link was started. */ 173 174struct pppd_stats link_stats; 175unsigned link_connect_time; 176int link_stats_valid; 177 178int error_count; 179 180/* 181 * We maintain a list of child process pids and 182 * functions to call when they exit. 183 */ 184struct subprocess { 185 pid_t pid; 186 char *prog; 187 void (*done) __P((void *)); 188 void *arg; 189 struct subprocess *next; 190}; 191 192static struct subprocess *children; 193 194/* Prototypes for procedures local to this file. */ 195 196static void setup_signals __P((void)); 197static void create_pidfile __P((int pid)); 198static void create_linkpidfile __P((int pid)); 199static void cleanup __P((void)); 200static void get_input __P((void)); 201static void calltimeout __P((void)); 202static struct timeval *timeleft __P((struct timeval *)); 203static void kill_my_pg __P((int)); 204static void hup __P((int)); 205static void term __P((int)); 206static void chld __P((int)); 207static void toggle_debug __P((int)); 208static void open_ccp __P((int)); 209static void bad_signal __P((int)); 210static void holdoff_end __P((void *)); 211static int reap_kids __P((int waitfor)); 212 213#ifdef USE_TDB 214static void update_db_entry __P((void)); 215static void add_db_key __P((const char *)); 216static void delete_db_key __P((const char *)); 217static void cleanup_db __P((void)); 218#endif 219 220static void handle_events __P((void)); 221static void print_link_stats __P((void)); 222 223extern char *ttyname __P((int)); 224extern char *getlogin __P((void)); 225int main __P((int, char *[])); 226 227#ifdef ultrix 228#undef O_NONBLOCK 229#define O_NONBLOCK O_NDELAY 230#endif 231 232#ifdef ULTRIX 233#define setlogmask(x) 234#endif 235 236/* 237 * PPP Data Link Layer "protocol" table. 238 * One entry per supported protocol. 239 * The last entry must be NULL. 240 */ 241struct protent *protocols[] = { 242 &lcp_protent, 243 &pap_protent, 244 &chap_protent, 245#ifdef CBCP_SUPPORT 246 &cbcp_protent, 247#endif 248 &ipcp_protent, 249#ifdef INET6 250 &ipv6cp_protent, 251#endif 252 &ccp_protent, 253 &ecp_protent, 254#ifdef IPX_CHANGE 255 &ipxcp_protent, 256#endif 257#ifdef AT_CHANGE 258 &atcp_protent, 259#endif 260 &eap_protent, 261 NULL 262}; 263 264/* 265 * If PPP_DRV_NAME is not defined, use the default "ppp" as the device name. 266 */ 267#if !defined(PPP_DRV_NAME) 268#define PPP_DRV_NAME "ppp" 269#endif /* !defined(PPP_DRV_NAME) */ 270 271int 272main(argc, argv) 273 int argc; 274 char *argv[]; 275{ 276 int i, t; 277 char *p; 278 struct passwd *pw; 279 struct protent *protp; 280 char numbuf[16]; 281 282 link_stats_valid = 0; 283 new_phase(PHASE_INITIALIZE); 284 285 script_env = NULL; 286 287 /* Initialize syslog facilities */ 288 reopen_log(); 289 290 if (gethostname(hostname, MAXNAMELEN) < 0 ) { 291 option_error("Couldn't get hostname: %m"); 292 exit(1); 293 } 294 hostname[MAXNAMELEN-1] = 0; 295 296 /* make sure we don't create world or group writable files. */ 297 umask(umask(0777) | 022); 298 299 uid = getuid(); 300 privileged = uid == 0; 301 slprintf(numbuf, sizeof(numbuf), "%d", uid); 302 script_setenv("ORIG_UID", numbuf, 0); 303 304 ngroups = getgroups(NGROUPS_MAX, groups); 305 306 /* 307 * Initialize magic number generator now so that protocols may 308 * use magic numbers in initialization. 309 */ 310 magic_init(); 311 312 /* 313 * Initialize each protocol. 314 */ 315 for (i = 0; (protp = protocols[i]) != NULL; ++i) 316 (*protp->init)(0); 317 318 /* 319 * Initialize the default channel. 320 */ 321 tty_init(); 322 323 progname = *argv; 324 325 /* 326 * Parse, in order, the system options file, the user's options file, 327 * and the command line arguments. 328 */ 329 if (!options_from_file(_PATH_SYSOPTIONS, !privileged, 0, 1) 330 || !options_from_user() 331 || !parse_args(argc-1, argv+1)) 332 exit(EXIT_OPTION_ERROR); 333 devnam_fixed = 1; /* can no longer change device name */ 334 335 /* 336 * Work out the device name, if it hasn't already been specified, 337 * and parse the tty's options file. 338 */ 339 if (the_channel->process_extra_options) 340 (*the_channel->process_extra_options)(); 341 342 if (debug) 343 setlogmask(LOG_UPTO(LOG_DEBUG)); 344 345 /* 346 * Check that we are running as root. 347 */ 348 if (geteuid() != 0) { 349 option_error("must be root to run %s, since it is not setuid-root", 350 argv[0]); 351 exit(EXIT_NOT_ROOT); 352 } 353 354 if (!ppp_available()) { 355 option_error("%s", no_ppp_msg); 356 exit(EXIT_NO_KERNEL_SUPPORT); 357 } 358 359 /* 360 * Check that the options given are valid and consistent. 361 */ 362 check_options(); 363 if (!sys_check_options()) 364 exit(EXIT_OPTION_ERROR); 365 auth_check_options(); 366#ifdef HAVE_MULTILINK 367 mp_check_options(); 368#endif 369 for (i = 0; (protp = protocols[i]) != NULL; ++i) 370 if (protp->check_options != NULL) 371 (*protp->check_options)(); 372 if (the_channel->check_options) 373 (*the_channel->check_options)(); 374 375 376 if (dump_options || dryrun) { 377 init_pr_log(NULL, LOG_INFO); 378 print_options(pr_log, NULL); 379 end_pr_log(); 380 } 381 382 if (dryrun) 383 die(0); 384 385 /* 386 * Initialize system-dependent stuff. 387 */ 388 sys_init(); 389 390 /* Make sure fds 0, 1, 2 are open to somewhere. */ 391 fd_devnull = open(_PATH_DEVNULL, O_RDWR); 392 if (fd_devnull < 0) 393 fatal("Couldn't open %s: %m", _PATH_DEVNULL); 394 while (fd_devnull <= 2) { 395 i = dup(fd_devnull); 396 if (i < 0) 397 fatal("Critical shortage of file descriptors: dup failed: %m"); 398 fd_devnull = i; 399 } 400 401#ifdef USE_TDB 402 pppdb = tdb_open(_PATH_PPPDB, 0, 0, O_RDWR|O_CREAT, 0644); 403 if (pppdb != NULL) { 404 slprintf(db_key, sizeof(db_key), "pppd%d", getpid()); 405 update_db_entry(); 406 } else { 407 warn("Warning: couldn't open ppp database %s", _PATH_PPPDB); 408 if (multilink) { 409 warn("Warning: disabling multilink"); 410 multilink = 0; 411 } 412 } 413#endif 414 415 /* 416 * Detach ourselves from the terminal, if required, 417 * and identify who is running us. 418 */ 419 if (!nodetach && !updetach) 420 detach(); 421 p = getlogin(); 422 if (p == NULL) { 423 pw = getpwuid(uid); 424 if (pw != NULL && pw->pw_name != NULL) 425 p = pw->pw_name; 426 else 427 p = "(unknown)"; 428 } 429 syslog(LOG_NOTICE, "pppd %s started by %s, uid %d", VERSION, p, uid); 430 script_setenv("PPPLOGNAME", p, 0); 431 432 if (devnam[0]) 433 script_setenv("DEVICE", devnam, 1); 434 slprintf(numbuf, sizeof(numbuf), "%d", getpid()); 435 script_setenv("PPPD_PID", numbuf, 1); 436 437 setup_signals(); 438 439 waiting = 0; 440 441 /* 442 * If we're doing dial-on-demand, set up the interface now. 443 */ 444 if (demand) { 445 /* 446 * Open the loopback channel and set it up to be the ppp interface. 447 */ 448#ifdef USE_TDB 449 tdb_writelock(pppdb); 450#endif 451 fd_loop = open_ppp_loopback(); 452 set_ifunit(1); 453#ifdef USE_TDB 454 tdb_writeunlock(pppdb); 455#endif 456 /* 457 * Configure the interface and mark it up, etc. 458 */ 459 demand_conf(); 460 create_linkpidfile(getpid()); 461 } 462 463 do_callback = 0; 464 for (;;) { 465 466 listen_time = 0; 467 need_holdoff = 1; 468 devfd = -1; 469 status = EXIT_OK; 470 ++unsuccess; 471 doing_callback = do_callback; 472 do_callback = 0; 473 474 if (demand && !doing_callback) { 475 /* 476 * Don't do anything until we see some activity. 477 */ 478 new_phase(PHASE_DORMANT); 479 demand_unblock(); 480 add_fd(fd_loop); 481 for (;;) { 482 handle_events(); 483 if (kill_link && !persist) 484 break; 485 if (get_loop_output()) 486 break; 487 } 488 remove_fd(fd_loop); 489 if (kill_link && !persist) 490 break; 491 492 /* 493 * Now we want to bring up the link. 494 */ 495 demand_block(); 496 info("Starting link"); 497 } 498 499 new_phase(PHASE_SERIALCONN); 500 501 devfd = the_channel->connect(); 502 if (devfd < 0) 503 goto fail; 504 505 /* set up the serial device as a ppp interface */ 506#ifdef USE_TDB 507 tdb_writelock(pppdb); 508#endif 509 fd_ppp = the_channel->establish_ppp(devfd); 510 if (fd_ppp < 0) { 511#ifdef USE_TDB 512 tdb_writeunlock(pppdb); 513#endif 514 status = EXIT_FATAL_ERROR; 515 goto disconnect; 516 } 517 /* create the pid file, now that we've obtained a ppp interface */ 518 if (!demand) 519 create_linkpidfile(getpid()); 520 521 if (!demand && ifunit >= 0) 522 set_ifunit(1); 523#ifdef USE_TDB 524 tdb_writeunlock(pppdb); 525#endif 526 527 /* 528 * Start opening the connection and wait for 529 * incoming events (reply, timeout, etc.). 530 */ 531 if (ifunit >= 0) 532 notice("Connect: %s <--> %s", ifname, ppp_devnam); 533 else 534 notice("Starting negotiation on %s", ppp_devnam); 535 gettimeofday(&start_time, NULL); 536 script_unsetenv("CONNECT_TIME"); 537 script_unsetenv("BYTES_SENT"); 538 script_unsetenv("BYTES_RCVD"); 539 lcp_lowerup(0); 540 541 add_fd(fd_ppp); 542 lcp_open(0); /* Start protocol */ 543 status = EXIT_NEGOTIATION_FAILED; 544 new_phase(PHASE_ESTABLISH); 545 while (phase != PHASE_DEAD) { 546 handle_events(); 547 get_input(); 548 if (kill_link) 549 lcp_close(0, "User request"); 550 if (open_ccp_flag) { 551 if (phase == PHASE_NETWORK || phase == PHASE_RUNNING) { 552 ccp_fsm[0].flags = OPT_RESTART; /* clears OPT_SILENT */ 553 (*ccp_protent.open)(0); 554 } 555 } 556 } 557 558 print_link_stats(); 559 560 /* 561 * Delete pid file before disestablishing ppp. Otherwise it 562 * can happen that another pppd gets the same unit and then 563 * we delete its pid file. 564 */ 565 if (!demand) { 566 if (pidfilename[0] != 0 567 && unlink(pidfilename) < 0 && errno != ENOENT) 568 warn("unable to delete pid file %s: %m", pidfilename); 569 pidfilename[0] = 0; 570 } 571 572 /* 573 * If we may want to bring the link up again, transfer 574 * the ppp unit back to the loopback. Set the 575 * real serial device back to its normal mode of operation. 576 */ 577 remove_fd(fd_ppp); 578 clean_check(); 579 the_channel->disestablish_ppp(devfd); 580 fd_ppp = -1; 581 if (!hungup) 582 lcp_lowerdown(0); 583 if (!demand) 584 script_unsetenv("IFNAME"); 585 586 /* 587 * Run disconnector script, if requested. 588 * XXX we may not be able to do this if the line has hung up! 589 */ 590 disconnect: 591 new_phase(PHASE_DISCONNECT); 592 if (the_channel->disconnect) 593 the_channel->disconnect(); 594 595 fail: 596 if (the_channel->cleanup) 597 (*the_channel->cleanup)(); 598 599 if (!demand) { 600 if (pidfilename[0] != 0 601 && unlink(pidfilename) < 0 && errno != ENOENT) 602 warn("unable to delete pid file %s: %m", pidfilename); 603 pidfilename[0] = 0; 604 } 605 606 if (!persist || (maxfail > 0 && unsuccess >= maxfail)) 607 break; 608 609 if (demand) 610 demand_discard(); 611 t = need_holdoff? holdoff: 0; 612 if (holdoff_hook) 613 t = (*holdoff_hook)(); 614 if (t > 0) { 615 new_phase(PHASE_HOLDOFF); 616 TIMEOUT(holdoff_end, NULL, t); 617 do { 618 handle_events(); 619 if (kill_link) 620 new_phase(PHASE_DORMANT); /* allow signal to end holdoff */ 621 } while (phase == PHASE_HOLDOFF); 622 if (!persist) 623 break; 624 } 625 } 626 627 /* Wait for scripts to finish */ 628 /* XXX should have a timeout here */ 629 while (n_children > 0) { 630 if (debug) { 631 struct subprocess *chp; 632 dbglog("Waiting for %d child processes...", n_children); 633 for (chp = children; chp != NULL; chp = chp->next) 634 dbglog(" script %s, pid %d", chp->prog, chp->pid); 635 } 636 if (reap_kids(1) < 0) 637 break; 638 } 639 640 die(status); 641 return 0; 642} 643 644/* 645 * handle_events - wait for something to happen and respond to it. 646 */ 647static void 648handle_events() 649{ 650 struct timeval timo; 651 sigset_t mask; 652 653 kill_link = open_ccp_flag = 0; 654 if (sigsetjmp(sigjmp, 1) == 0) { 655 sigprocmask(SIG_BLOCK, &mask, NULL); 656 if (got_sighup || got_sigterm || got_sigusr2 || got_sigchld) { 657 sigprocmask(SIG_UNBLOCK, &mask, NULL); 658 } else { 659 waiting = 1; 660 sigprocmask(SIG_UNBLOCK, &mask, NULL); 661 wait_input(timeleft(&timo)); 662 } 663 } 664 waiting = 0; 665 calltimeout(); 666 if (got_sighup) { 667 kill_link = 1; 668 got_sighup = 0; 669 if (status != EXIT_HANGUP) 670 status = EXIT_USER_REQUEST; 671 } 672 if (got_sigterm) { 673 kill_link = 1; 674 persist = 0; 675 status = EXIT_USER_REQUEST; 676 got_sigterm = 0; 677 } 678 if (got_sigchld) { 679 reap_kids(0); /* Don't leave dead kids lying around */ 680 got_sigchld = 0; 681 } 682 if (got_sigusr2) { 683 open_ccp_flag = 1; 684 got_sigusr2 = 0; 685 } 686} 687 688/* 689 * setup_signals - initialize signal handling. 690 */ 691static void 692setup_signals() 693{ 694 struct sigaction sa; 695 sigset_t mask; 696 697 /* 698 * Compute mask of all interesting signals and install signal handlers 699 * for each. Only one signal handler may be active at a time. Therefore, 700 * all other signals should be masked when any handler is executing. 701 */ 702 sigemptyset(&mask); 703 sigaddset(&mask, SIGHUP); 704 sigaddset(&mask, SIGINT); 705 sigaddset(&mask, SIGTERM); 706 sigaddset(&mask, SIGCHLD); 707 sigaddset(&mask, SIGUSR2); 708 709#define SIGNAL(s, handler) do { \ 710 sa.sa_handler = handler; \ 711 if (sigaction(s, &sa, NULL) < 0) \ 712 fatal("Couldn't establish signal handler (%d): %m", s); \ 713 } while (0) 714 715 sa.sa_mask = mask; 716 sa.sa_flags = 0; 717 SIGNAL(SIGHUP, hup); /* Hangup */ 718 SIGNAL(SIGINT, term); /* Interrupt */ 719 SIGNAL(SIGTERM, term); /* Terminate */ 720 SIGNAL(SIGCHLD, chld); 721 722 SIGNAL(SIGUSR1, toggle_debug); /* Toggle debug flag */ 723 SIGNAL(SIGUSR2, open_ccp); /* Reopen CCP */ 724 725 /* 726 * Install a handler for other signals which would otherwise 727 * cause pppd to exit without cleaning up. 728 */ 729 SIGNAL(SIGABRT, bad_signal); 730 SIGNAL(SIGALRM, bad_signal); 731 SIGNAL(SIGFPE, bad_signal); 732 SIGNAL(SIGILL, bad_signal); 733 SIGNAL(SIGPIPE, bad_signal); 734 SIGNAL(SIGQUIT, bad_signal); 735 SIGNAL(SIGSEGV, bad_signal); 736#ifdef SIGBUS 737 SIGNAL(SIGBUS, bad_signal); 738#endif 739#ifdef SIGEMT 740 SIGNAL(SIGEMT, bad_signal); 741#endif 742#ifdef SIGPOLL 743 SIGNAL(SIGPOLL, bad_signal); 744#endif 745#ifdef SIGPROF 746 SIGNAL(SIGPROF, bad_signal); 747#endif 748#ifdef SIGSYS 749 SIGNAL(SIGSYS, bad_signal); 750#endif 751#ifdef SIGTRAP 752 SIGNAL(SIGTRAP, bad_signal); 753#endif 754#ifdef SIGVTALRM 755 SIGNAL(SIGVTALRM, bad_signal); 756#endif 757#ifdef SIGXCPU 758 SIGNAL(SIGXCPU, bad_signal); 759#endif 760#ifdef SIGXFSZ 761 SIGNAL(SIGXFSZ, bad_signal); 762#endif 763 764 /* 765 * Apparently we can get a SIGPIPE when we call syslog, if 766 * syslogd has died and been restarted. Ignoring it seems 767 * be sufficient. 768 */ 769 signal(SIGPIPE, SIG_IGN); 770} 771 772/* 773 * set_ifunit - do things we need to do once we know which ppp 774 * unit we are using. 775 */ 776void 777set_ifunit(iskey) 778 int iskey; 779{ 780 info("Using interface %s%d", PPP_DRV_NAME, ifunit); 781 slprintf(ifname, sizeof(ifname), "%s%d", PPP_DRV_NAME, ifunit); 782 script_setenv("IFNAME", ifname, iskey); 783 if (iskey) { 784 create_pidfile(getpid()); /* write pid to file */ 785 create_linkpidfile(getpid()); 786 } 787} 788 789/* 790 * detach - detach us from the controlling terminal. 791 */ 792void 793detach() 794{ 795 int pid; 796 char numbuf[16]; 797 int pipefd[2]; 798 799 if (detached) 800 return; 801 if (pipe(pipefd) == -1) 802 pipefd[0] = pipefd[1] = -1; 803 if ((pid = fork()) < 0) { 804 error("Couldn't detach (fork failed: %m)"); 805 die(1); /* or just return? */ 806 } 807 if (pid != 0) { 808 /* parent */ 809 notify(pidchange, pid); 810 /* update pid files if they have been written already */ 811 if (pidfilename[0]) 812 create_pidfile(pid); 813 if (linkpidfile[0]) 814 create_linkpidfile(pid); 815 exit(0); /* parent dies */ 816 } 817 setsid(); 818 chdir("/"); 819 dup2(fd_devnull, 0); 820 dup2(fd_devnull, 1); 821 dup2(fd_devnull, 2); 822 detached = 1; 823 if (log_default) 824 log_to_fd = -1; 825 slprintf(numbuf, sizeof(numbuf), "%d", getpid()); 826 script_setenv("PPPD_PID", numbuf, 1); 827 828 /* wait for parent to finish updating pid & lock files and die */ 829 close(pipefd[1]); 830 complete_read(pipefd[0], numbuf, 1); 831 close(pipefd[0]); 832} 833 834/* 835 * reopen_log - (re)open our connection to syslog. 836 */ 837void 838reopen_log() 839{ 840#ifdef ULTRIX 841 openlog("pppd", LOG_PID); 842#else 843 openlog("pppd", LOG_PID | LOG_NDELAY, LOG_PPP); 844 setlogmask(LOG_UPTO(LOG_INFO)); 845#endif 846} 847 848/* 849 * Create a file containing our process ID. 850 */ 851static void 852create_pidfile(pid) 853 int pid; 854{ 855 FILE *pidfile; 856 857 slprintf(pidfilename, sizeof(pidfilename), "%s%s.pid", 858 _PATH_VARRUN, ifname); 859 if ((pidfile = fopen(pidfilename, "w")) != NULL) { 860 fprintf(pidfile, "%d\n", pid); 861 (void) fclose(pidfile); 862 } else { 863 error("Failed to create pid file %s: %m", pidfilename); 864 pidfilename[0] = 0; 865 } 866} 867 868static void 869create_linkpidfile(pid) 870 int pid; 871{ 872 FILE *pidfile; 873 874 if (linkname[0] == 0) 875 return; 876 script_setenv("LINKNAME", linkname, 1); 877 slprintf(linkpidfile, sizeof(linkpidfile), "%sppp-%s.pid", 878 _PATH_VARRUN, linkname); 879 if ((pidfile = fopen(linkpidfile, "w")) != NULL) { 880 fprintf(pidfile, "%d\n", pid); 881 if (ifname[0]) 882 fprintf(pidfile, "%s\n", ifname); 883 (void) fclose(pidfile); 884 } else { 885 error("Failed to create pid file %s: %m", linkpidfile); 886 linkpidfile[0] = 0; 887 } 888} 889 890/* 891 * holdoff_end - called via a timeout when the holdoff period ends. 892 */ 893static void 894holdoff_end(arg) 895 void *arg; 896{ 897 new_phase(PHASE_DORMANT); 898} 899 900/* List of protocol names, to make our messages a little more informative. */ 901struct protocol_list { 902 u_short proto; 903 const char *name; 904} protocol_list[] = { 905 { 0x21, "IP" }, 906 { 0x23, "OSI Network Layer" }, 907 { 0x25, "Xerox NS IDP" }, 908 { 0x27, "DECnet Phase IV" }, 909 { 0x29, "Appletalk" }, 910 { 0x2b, "Novell IPX" }, 911 { 0x2d, "VJ compressed TCP/IP" }, 912 { 0x2f, "VJ uncompressed TCP/IP" }, 913 { 0x31, "Bridging PDU" }, 914 { 0x33, "Stream Protocol ST-II" }, 915 { 0x35, "Banyan Vines" }, 916 { 0x39, "AppleTalk EDDP" }, 917 { 0x3b, "AppleTalk SmartBuffered" }, 918 { 0x3d, "Multi-Link" }, 919 { 0x3f, "NETBIOS Framing" }, 920 { 0x41, "Cisco Systems" }, 921 { 0x43, "Ascom Timeplex" }, 922 { 0x45, "Fujitsu Link Backup and Load Balancing (LBLB)" }, 923 { 0x47, "DCA Remote Lan" }, 924 { 0x49, "Serial Data Transport Protocol (PPP-SDTP)" }, 925 { 0x4b, "SNA over 802.2" }, 926 { 0x4d, "SNA" }, 927 { 0x4f, "IP6 Header Compression" }, 928 { 0x6f, "Stampede Bridging" }, 929 { 0xfb, "single-link compression" }, 930 { 0xfd, "1st choice compression" }, 931 { 0x0201, "802.1d Hello Packets" }, 932 { 0x0203, "IBM Source Routing BPDU" }, 933 { 0x0205, "DEC LANBridge100 Spanning Tree" }, 934 { 0x0231, "Luxcom" }, 935 { 0x0233, "Sigma Network Systems" }, 936 { 0x8021, "Internet Protocol Control Protocol" }, 937 { 0x8023, "OSI Network Layer Control Protocol" }, 938 { 0x8025, "Xerox NS IDP Control Protocol" }, 939 { 0x8027, "DECnet Phase IV Control Protocol" }, 940 { 0x8029, "Appletalk Control Protocol" }, 941 { 0x802b, "Novell IPX Control Protocol" }, 942 { 0x8031, "Bridging NCP" }, 943 { 0x8033, "Stream Protocol Control Protocol" }, 944 { 0x8035, "Banyan Vines Control Protocol" }, 945 { 0x803d, "Multi-Link Control Protocol" }, 946 { 0x803f, "NETBIOS Framing Control Protocol" }, 947 { 0x8041, "Cisco Systems Control Protocol" }, 948 { 0x8043, "Ascom Timeplex" }, 949 { 0x8045, "Fujitsu LBLB Control Protocol" }, 950 { 0x8047, "DCA Remote Lan Network Control Protocol (RLNCP)" }, 951 { 0x8049, "Serial Data Control Protocol (PPP-SDCP)" }, 952 { 0x804b, "SNA over 802.2 Control Protocol" }, 953 { 0x804d, "SNA Control Protocol" }, 954 { 0x804f, "IP6 Header Compression Control Protocol" }, 955 { 0x006f, "Stampede Bridging Control Protocol" }, 956 { 0x80fb, "Single Link Compression Control Protocol" }, 957 { 0x80fd, "Compression Control Protocol" }, 958 { 0xc021, "Link Control Protocol" }, 959 { 0xc023, "Password Authentication Protocol" }, 960 { 0xc025, "Link Quality Report" }, 961 { 0xc027, "Shiva Password Authentication Protocol" }, 962 { 0xc029, "CallBack Control Protocol (CBCP)" }, 963 { 0xc081, "Container Control Protocol" }, 964 { 0xc223, "Challenge Handshake Authentication Protocol" }, 965 { 0xc281, "Proprietary Authentication Protocol" }, 966 { 0, NULL }, 967}; 968 969/* 970 * protocol_name - find a name for a PPP protocol. 971 */ 972const char * 973protocol_name(proto) 974 int proto; 975{ 976 struct protocol_list *lp; 977 978 for (lp = protocol_list; lp->proto != 0; ++lp) 979 if (proto == lp->proto) 980 return lp->name; 981 return NULL; 982} 983 984/* 985 * get_input - called when incoming data is available. 986 */ 987static void 988get_input() 989{ 990 int len, i; 991 u_char *p; 992 u_short protocol; 993 struct protent *protp; 994 995 p = inpacket_buf; /* point to beginning of packet buffer */ 996 997 len = read_packet(inpacket_buf); 998 if (len < 0) 999 return; 1000 1001 if (len == 0) { 1002 notice("Modem hangup"); 1003 hungup = 1; 1004 status = EXIT_HANGUP; 1005 lcp_lowerdown(0); /* serial link is no longer available */ 1006 link_terminated(0); 1007 return; 1008 } 1009 1010 if (len < PPP_HDRLEN) { 1011 dbglog("received short packet:%.*B", len, p); 1012 return; 1013 } 1014 1015 dump_packet("rcvd", p, len); 1016 if (snoop_recv_hook) snoop_recv_hook(p, len); 1017 1018 p += 2; /* Skip address and control */ 1019 GETSHORT(protocol, p); 1020 len -= PPP_HDRLEN; 1021 1022 /* 1023 * Toss all non-LCP packets unless LCP is OPEN. 1024 */ 1025 if (protocol != PPP_LCP && lcp_fsm[0].state != OPENED) { 1026 dbglog("Discarded non-LCP packet when LCP not open"); 1027 return; 1028 } 1029 1030 /* 1031 * Until we get past the authentication phase, toss all packets 1032 * except LCP, LQR and authentication packets. 1033 */ 1034 if (phase <= PHASE_AUTHENTICATE 1035 && !(protocol == PPP_LCP || protocol == PPP_LQR 1036 || protocol == PPP_PAP || protocol == PPP_CHAP || 1037 protocol == PPP_EAP)) { 1038 dbglog("discarding proto 0x%x in phase %d", 1039 protocol, phase); 1040 return; 1041 } 1042 1043 /* 1044 * Upcall the proper protocol input routine. 1045 */ 1046 for (i = 0; (protp = protocols[i]) != NULL; ++i) { 1047 if (protp->protocol == protocol && protp->enabled_flag) { 1048 (*protp->input)(0, p, len); 1049 return; 1050 } 1051 if (protocol == (protp->protocol & ~0x8000) && protp->enabled_flag 1052 && protp->datainput != NULL) { 1053 (*protp->datainput)(0, p, len); 1054 return; 1055 } 1056 } 1057 1058 if (debug) { 1059 const char *pname = protocol_name(protocol); 1060 if (pname != NULL) 1061 warn("Unsupported protocol '%s' (0x%x) received", pname, protocol); 1062 else 1063 warn("Unsupported protocol 0x%x received", protocol); 1064 } 1065 lcp_sprotrej(0, p - PPP_HDRLEN, len + PPP_HDRLEN); 1066} 1067 1068/* 1069 * ppp_send_config - configure the transmit-side characteristics of 1070 * the ppp interface. Returns -1, indicating an error, if the channel 1071 * send_config procedure called error() (or incremented error_count 1072 * itself), otherwise 0. 1073 */ 1074int 1075ppp_send_config(unit, mtu, accm, pcomp, accomp) 1076 int unit, mtu; 1077 u_int32_t accm; 1078 int pcomp, accomp; 1079{ 1080 int errs; 1081 1082 if (the_channel->send_config == NULL) 1083 return 0; 1084 errs = error_count; 1085 (*the_channel->send_config)(mtu, accm, pcomp, accomp); 1086 return (error_count != errs)? -1: 0; 1087} 1088 1089/* 1090 * ppp_recv_config - configure the receive-side characteristics of 1091 * the ppp interface. Returns -1, indicating an error, if the channel 1092 * recv_config procedure called error() (or incremented error_count 1093 * itself), otherwise 0. 1094 */ 1095int 1096ppp_recv_config(unit, mru, accm, pcomp, accomp) 1097 int unit, mru; 1098 u_int32_t accm; 1099 int pcomp, accomp; 1100{ 1101 int errs; 1102 1103 if (the_channel->recv_config == NULL) 1104 return 0; 1105 errs = error_count; 1106 (*the_channel->recv_config)(mru, accm, pcomp, accomp); 1107 return (error_count != errs)? -1: 0; 1108} 1109 1110/* 1111 * new_phase - signal the start of a new phase of pppd's operation. 1112 */ 1113void 1114new_phase(p) 1115 int p; 1116{ 1117 phase = p; 1118 if (new_phase_hook) 1119 (*new_phase_hook)(p); 1120 notify(phasechange, p); 1121} 1122 1123/* 1124 * die - clean up state and exit with the specified status. 1125 */ 1126void 1127die(status) 1128 int status; 1129{ 1130 print_link_stats(); 1131 cleanup(); 1132 notify(exitnotify, status); 1133 syslog(LOG_INFO, "Exit."); 1134 exit(status); 1135} 1136 1137/* 1138 * cleanup - restore anything which needs to be restored before we exit 1139 */ 1140/* ARGSUSED */ 1141static void 1142cleanup() 1143{ 1144 sys_cleanup(); 1145 1146 if (fd_ppp >= 0) 1147 the_channel->disestablish_ppp(devfd); 1148 if (the_channel->cleanup) 1149 (*the_channel->cleanup)(); 1150 1151 if (pidfilename[0] != 0 && unlink(pidfilename) < 0 && errno != ENOENT) 1152 warn("unable to delete pid file %s: %m", pidfilename); 1153 pidfilename[0] = 0; 1154 if (linkpidfile[0] != 0 && unlink(linkpidfile) < 0 && errno != ENOENT) 1155 warn("unable to delete pid file %s: %m", linkpidfile); 1156 linkpidfile[0] = 0; 1157 1158#ifdef USE_TDB 1159 if (pppdb != NULL) 1160 cleanup_db(); 1161#endif 1162 1163} 1164 1165void 1166print_link_stats() 1167{ 1168 /* 1169 * Print connect time and statistics. 1170 */ 1171 if (link_stats_valid) { 1172 int t = (link_connect_time + 5) / 6; /* 1/10ths of minutes */ 1173 info("Connect time %d.%d minutes.", t/10, t%10); 1174 info("Sent %u bytes, received %u bytes.", 1175 link_stats.bytes_out, link_stats.bytes_in); 1176 } 1177} 1178 1179/* 1180 * update_link_stats - get stats at link termination. 1181 */ 1182void 1183update_link_stats(u) 1184 int u; 1185{ 1186 struct timeval now; 1187 char numbuf[32]; 1188 1189 if (!get_ppp_stats(u, &link_stats) 1190 || gettimeofday(&now, NULL) < 0) 1191 return; 1192 link_connect_time = now.tv_sec - start_time.tv_sec; 1193 link_stats_valid = 1; 1194 1195 slprintf(numbuf, sizeof(numbuf), "%u", link_connect_time); 1196 script_setenv("CONNECT_TIME", numbuf, 0); 1197 slprintf(numbuf, sizeof(numbuf), "%u", link_stats.bytes_out); 1198 script_setenv("BYTES_SENT", numbuf, 0); 1199 slprintf(numbuf, sizeof(numbuf), "%u", link_stats.bytes_in); 1200 script_setenv("BYTES_RCVD", numbuf, 0); 1201} 1202 1203 1204struct callout { 1205 struct timeval c_time; /* time at which to call routine */ 1206 void *c_arg; /* argument to routine */ 1207 void (*c_func) __P((void *)); /* routine */ 1208 struct callout *c_next; 1209}; 1210 1211static struct callout *callout = NULL; /* Callout list */ 1212static struct timeval timenow; /* Current time */ 1213 1214/* 1215 * timeout - Schedule a timeout. 1216 */ 1217void 1218timeout(func, arg, secs, usecs) 1219 void (*func) __P((void *)); 1220 void *arg; 1221 int secs, usecs; 1222{ 1223 struct callout *newp, *p, **pp; 1224 1225 MAINDEBUG(("Timeout %p:%p in %d.%03d seconds.", func, arg, 1226 secs, usecs/1000)); 1227 1228 /* 1229 * Allocate timeout. 1230 */ 1231 if ((newp = (struct callout *) malloc(sizeof(struct callout))) == NULL) 1232 fatal("Out of memory in timeout()!"); 1233 newp->c_arg = arg; 1234 newp->c_func = func; 1235 gettimeofday(&timenow, NULL); 1236 newp->c_time.tv_sec = timenow.tv_sec + secs; 1237 newp->c_time.tv_usec = timenow.tv_usec + usecs; 1238 if (newp->c_time.tv_usec >= 1000000) { 1239 newp->c_time.tv_sec += newp->c_time.tv_usec / 1000000; 1240 newp->c_time.tv_usec %= 1000000; 1241 } 1242 1243 /* 1244 * Find correct place and link it in. 1245 */ 1246 for (pp = &callout; (p = *pp); pp = &p->c_next) 1247 if (newp->c_time.tv_sec < p->c_time.tv_sec 1248 || (newp->c_time.tv_sec == p->c_time.tv_sec 1249 && newp->c_time.tv_usec < p->c_time.tv_usec)) 1250 break; 1251 newp->c_next = p; 1252 *pp = newp; 1253} 1254 1255 1256/* 1257 * untimeout - Unschedule a timeout. 1258 */ 1259void 1260untimeout(func, arg) 1261 void (*func) __P((void *)); 1262 void *arg; 1263{ 1264 struct callout **copp, *freep; 1265 1266 MAINDEBUG(("Untimeout %p:%p.", func, arg)); 1267 1268 /* 1269 * Find first matching timeout and remove it from the list. 1270 */ 1271 for (copp = &callout; (freep = *copp); copp = &freep->c_next) 1272 if (freep->c_func == func && freep->c_arg == arg) { 1273 *copp = freep->c_next; 1274 free((char *) freep); 1275 break; 1276 } 1277} 1278 1279 1280/* 1281 * calltimeout - Call any timeout routines which are now due. 1282 */ 1283static void 1284calltimeout() 1285{ 1286 struct callout *p; 1287 1288 while (callout != NULL) { 1289 p = callout; 1290 1291 if (gettimeofday(&timenow, NULL) < 0) 1292 fatal("Failed to get time of day: %m"); 1293 if (!(p->c_time.tv_sec < timenow.tv_sec 1294 || (p->c_time.tv_sec == timenow.tv_sec 1295 && p->c_time.tv_usec <= timenow.tv_usec))) 1296 break; /* no, it's not time yet */ 1297 1298 callout = p->c_next; 1299 (*p->c_func)(p->c_arg); 1300 1301 free((char *) p); 1302 } 1303} 1304 1305 1306/* 1307 * timeleft - return the length of time until the next timeout is due. 1308 */ 1309static struct timeval * 1310timeleft(tvp) 1311 struct timeval *tvp; 1312{ 1313 if (callout == NULL) 1314 return NULL; 1315 1316 gettimeofday(&timenow, NULL); 1317 tvp->tv_sec = callout->c_time.tv_sec - timenow.tv_sec; 1318 tvp->tv_usec = callout->c_time.tv_usec - timenow.tv_usec; 1319 if (tvp->tv_usec < 0) { 1320 tvp->tv_usec += 1000000; 1321 tvp->tv_sec -= 1; 1322 } 1323 if (tvp->tv_sec < 0) 1324 tvp->tv_sec = tvp->tv_usec = 0; 1325 1326 return tvp; 1327} 1328 1329 1330/* 1331 * kill_my_pg - send a signal to our process group, and ignore it ourselves. 1332 */ 1333static void 1334kill_my_pg(sig) 1335 int sig; 1336{ 1337 struct sigaction act, oldact; 1338 1339 act.sa_handler = SIG_IGN; 1340 act.sa_flags = 0; 1341 sigaction(sig, &act, &oldact); 1342 kill(0, sig); 1343 sigaction(sig, &oldact, NULL); 1344} 1345 1346 1347/* 1348 * hup - Catch SIGHUP signal. 1349 * 1350 * Indicates that the physical layer has been disconnected. 1351 * We don't rely on this indication; if the user has sent this 1352 * signal, we just take the link down. 1353 */ 1354static void 1355hup(sig) 1356 int sig; 1357{ 1358 info("Hangup (SIGHUP)"); 1359 got_sighup = 1; 1360 if (conn_running) 1361 /* Send the signal to the [dis]connector process(es) also */ 1362 kill_my_pg(sig); 1363 notify(sigreceived, sig); 1364 if (waiting) 1365 siglongjmp(sigjmp, 1); 1366} 1367 1368 1369/* 1370 * term - Catch SIGTERM signal and SIGINT signal (^C/del). 1371 * 1372 * Indicates that we should initiate a graceful disconnect and exit. 1373 */ 1374/*ARGSUSED*/ 1375static void 1376term(sig) 1377 int sig; 1378{ 1379 info("Terminating on signal %d.", sig); 1380 got_sigterm = 1; 1381 if (conn_running) 1382 /* Send the signal to the [dis]connector process(es) also */ 1383 kill_my_pg(sig); 1384 notify(sigreceived, sig); 1385 if (waiting) 1386 siglongjmp(sigjmp, 1); 1387} 1388 1389 1390/* 1391 * chld - Catch SIGCHLD signal. 1392 * Sets a flag so we will call reap_kids in the mainline. 1393 */ 1394static void 1395chld(sig) 1396 int sig; 1397{ 1398 got_sigchld = 1; 1399 if (waiting) 1400 siglongjmp(sigjmp, 1); 1401} 1402 1403 1404/* 1405 * toggle_debug - Catch SIGUSR1 signal. 1406 * 1407 * Toggle debug flag. 1408 */ 1409/*ARGSUSED*/ 1410static void 1411toggle_debug(sig) 1412 int sig; 1413{ 1414 debug = !debug; 1415 if (debug) { 1416 setlogmask(LOG_UPTO(LOG_DEBUG)); 1417 } else { 1418 setlogmask(LOG_UPTO(LOG_WARNING)); 1419 } 1420} 1421 1422 1423/* 1424 * open_ccp - Catch SIGUSR2 signal. 1425 * 1426 * Try to (re)negotiate compression. 1427 */ 1428/*ARGSUSED*/ 1429static void 1430open_ccp(sig) 1431 int sig; 1432{ 1433 got_sigusr2 = 1; 1434 if (waiting) 1435 siglongjmp(sigjmp, 1); 1436} 1437 1438 1439/* 1440 * bad_signal - We've caught a fatal signal. Clean up state and exit. 1441 */ 1442static void 1443bad_signal(sig) 1444 int sig; 1445{ 1446 static int crashed = 0; 1447 1448 if (crashed) 1449 _exit(127); 1450 crashed = 1; 1451 error("Fatal signal %d", sig); 1452 if (conn_running) 1453 kill_my_pg(SIGTERM); 1454 notify(sigreceived, sig); 1455 die(127); 1456} 1457 1458/* 1459 * safe_fork - Create a child process. The child closes all the 1460 * file descriptors that we don't want to leak to a script. 1461 * The parent waits for the child to do this before returning. 1462 */ 1463pid_t 1464safe_fork() 1465{ 1466 pid_t pid; 1467 int pipefd[2]; 1468 char buf[1]; 1469 1470 if (pipe(pipefd) == -1) 1471 pipefd[0] = pipefd[1] = -1; 1472 pid = fork(); 1473 if (pid < 0) 1474 return -1; 1475 if (pid > 0) { 1476 close(pipefd[1]); 1477 /* this read() blocks until the close(pipefd[1]) below */ 1478 complete_read(pipefd[0], buf, 1); 1479 close(pipefd[0]); 1480 return pid; 1481 } 1482 sys_close(); 1483#ifdef USE_TDB 1484 tdb_close(pppdb); 1485#endif 1486 notify(fork_notifier, 0); 1487 close(pipefd[0]); 1488 /* this close unblocks the read() call above in the parent */ 1489 close(pipefd[1]); 1490 return 0; 1491} 1492 1493/* 1494 * device_script - run a program to talk to the specified fds 1495 * (e.g. to run the connector or disconnector script). 1496 * stderr gets connected to the log fd or to the _PATH_CONNERRS file. 1497 */ 1498int 1499device_script(program, in, out, dont_wait) 1500 char *program; 1501 int in, out; 1502 int dont_wait; 1503{ 1504 int pid; 1505 int status = -1; 1506 int errfd; 1507 int fd; 1508 1509 ++conn_running; 1510 pid = safe_fork(); 1511 1512 if (pid < 0) { 1513 --conn_running; 1514 error("Failed to create child process: %m"); 1515 return -1; 1516 } 1517 1518 if (pid != 0) { 1519 if (dont_wait) { 1520 record_child(pid, program, NULL, NULL); 1521 status = 0; 1522 } else { 1523 while (waitpid(pid, &status, 0) < 0) { 1524 if (errno == EINTR) 1525 continue; 1526 fatal("error waiting for (dis)connection process: %m"); 1527 } 1528 --conn_running; 1529 } 1530 return (status == 0 ? 0 : -1); 1531 } 1532 1533 /* here we are executing in the child */ 1534 1535 /* make sure fds 0, 1, 2 are occupied */ 1536 while ((fd = dup(in)) >= 0) { 1537 if (fd > 2) { 1538 close(fd); 1539 break; 1540 } 1541 } 1542 1543 /* dup in and out to fds > 2 */ 1544 { 1545 int fd1 = in, fd2 = out, fd3 = log_to_fd; 1546 1547 in = dup(in); 1548 out = dup(out); 1549 if (log_to_fd >= 0) { 1550 errfd = dup(log_to_fd); 1551 } else { 1552 errfd = open(_PATH_CONNERRS, O_WRONLY | O_APPEND | O_CREAT, 0600); 1553 } 1554 close(fd1); 1555 close(fd2); 1556 close(fd3); 1557 } 1558 1559 /* close fds 0 - 2 and any others we can think of */ 1560 close(0); 1561 close(1); 1562 close(2); 1563 if (the_channel->close) 1564 (*the_channel->close)(); 1565 closelog(); 1566 close(fd_devnull); 1567 1568 /* dup the in, out, err fds to 0, 1, 2 */ 1569 dup2(in, 0); 1570 close(in); 1571 dup2(out, 1); 1572 close(out); 1573 if (errfd >= 0) { 1574 dup2(errfd, 2); 1575 close(errfd); 1576 } 1577 1578 setuid(uid); 1579 if (getuid() != uid) { 1580 error("setuid failed"); 1581 exit(1); 1582 } 1583 setgid(getgid()); 1584 execl("/bin/sh", "sh", "-c", program, (char *)0); 1585 error("could not exec /bin/sh: %m"); 1586 exit(99); 1587 /* NOTREACHED */ 1588} 1589 1590 1591/* 1592 * run-program - execute a program with given arguments, 1593 * but don't wait for it. 1594 * If the program can't be executed, logs an error unless 1595 * must_exist is 0 and the program file doesn't exist. 1596 * Returns -1 if it couldn't fork, 0 if the file doesn't exist 1597 * or isn't an executable plain file, or the process ID of the child. 1598 * If done != NULL, (*done)(arg) will be called later (within 1599 * reap_kids) iff the return value is > 0. 1600 */ 1601pid_t 1602run_program(prog, args, must_exist, done, arg) 1603 char *prog; 1604 char **args; 1605 int must_exist; 1606 void (*done) __P((void *)); 1607 void *arg; 1608{ 1609 int pid; 1610 struct stat sbuf; 1611 1612 /* 1613 * First check if the file exists and is executable. 1614 * We don't use access() because that would use the 1615 * real user-id, which might not be root, and the script 1616 * might be accessible only to root. 1617 */ 1618 errno = EINVAL; 1619 if (stat(prog, &sbuf) < 0 || !S_ISREG(sbuf.st_mode) 1620 || (sbuf.st_mode & (S_IXUSR|S_IXGRP|S_IXOTH)) == 0) { 1621 if (must_exist || errno != ENOENT) 1622 warn("Can't execute %s: %m", prog); 1623 return 0; 1624 } 1625 1626 pid = safe_fork(); 1627 if (pid == -1) { 1628 error("Failed to create child process for %s: %m", prog); 1629 return -1; 1630 } 1631 if (pid != 0) { 1632 if (debug) 1633 dbglog("Script %s started (pid %d)", prog, pid); 1634 record_child(pid, prog, done, arg); 1635 return pid; 1636 } 1637 1638 /* Leave the current location */ 1639 (void) setsid(); /* No controlling tty. */ 1640 (void) umask (S_IRWXG|S_IRWXO); 1641 (void) chdir ("/"); /* no current directory. */ 1642 setuid(0); /* set real UID = root */ 1643 setgid(getegid()); 1644 1645 /* Ensure that nothing of our device environment is inherited. */ 1646 closelog(); 1647 if (the_channel->close) 1648 (*the_channel->close)(); 1649 1650 /* Don't pass handles to the PPP device, even by accident. */ 1651 dup2(fd_devnull, 0); 1652 dup2(fd_devnull, 1); 1653 dup2(fd_devnull, 2); 1654 close(fd_devnull); 1655 1656#ifdef BSD 1657 /* Force the priority back to zero if pppd is running higher. */ 1658 if (setpriority (PRIO_PROCESS, 0, 0) < 0) 1659 warn("can't reset priority to 0: %m"); 1660#endif 1661 1662 /* SysV recommends a second fork at this point. */ 1663 1664 /* run the program */ 1665 execve(prog, args, script_env); 1666 if (must_exist || errno != ENOENT) { 1667 /* have to reopen the log, there's nowhere else 1668 for the message to go. */ 1669 reopen_log(); 1670 syslog(LOG_ERR, "Can't execute %s: %m", prog); 1671 closelog(); 1672 } 1673 _exit(-1); 1674} 1675 1676 1677/* 1678 * record_child - add a child process to the list for reap_kids 1679 * to use. 1680 */ 1681void 1682record_child(pid, prog, done, arg) 1683 int pid; 1684 char *prog; 1685 void (*done) __P((void *)); 1686 void *arg; 1687{ 1688 struct subprocess *chp; 1689 1690 ++n_children; 1691 1692 chp = (struct subprocess *) malloc(sizeof(struct subprocess)); 1693 if (chp == NULL) { 1694 warn("losing track of %s process", prog); 1695 } else { 1696 chp->pid = pid; 1697 chp->prog = prog; 1698 chp->done = done; 1699 chp->arg = arg; 1700 chp->next = children; 1701 children = chp; 1702 } 1703} 1704 1705 1706/* 1707 * reap_kids - get status from any dead child processes, 1708 * and log a message for abnormal terminations. 1709 */ 1710static int 1711reap_kids(waitfor) 1712 int waitfor; 1713{ 1714 int pid, status; 1715 struct subprocess *chp, **prevp; 1716 1717 if (n_children == 0) 1718 return 0; 1719 while ((pid = waitpid(-1, &status, (waitfor? 0: WNOHANG))) != -1 1720 && pid != 0) { 1721 for (prevp = &children; (chp = *prevp) != NULL; prevp = &chp->next) { 1722 if (chp->pid == pid) { 1723 --n_children; 1724 *prevp = chp->next; 1725 break; 1726 } 1727 } 1728 if (WIFSIGNALED(status)) { 1729 warn("Child process %s (pid %d) terminated with signal %d", 1730 (chp? chp->prog: "??"), pid, WTERMSIG(status)); 1731 } else if (debug) 1732 dbglog("Script %s finished (pid %d), status = 0x%x", 1733 (chp? chp->prog: "??"), pid, 1734 WIFEXITED(status) ? WEXITSTATUS(status) : status); 1735 if (chp && chp->done) 1736 (*chp->done)(chp->arg); 1737 if (chp) 1738 free(chp); 1739 } 1740 if (pid == -1) { 1741 if (errno == ECHILD) 1742 return -1; 1743 if (errno != EINTR) 1744 error("Error waiting for child process: %m"); 1745 } 1746 return 0; 1747} 1748 1749/* 1750 * add_notifier - add a new function to be called when something happens. 1751 */ 1752void 1753add_notifier(notif, func, arg) 1754 struct notifier **notif; 1755 notify_func func; 1756 void *arg; 1757{ 1758 struct notifier *np; 1759 1760 np = malloc(sizeof(struct notifier)); 1761 if (np == 0) 1762 novm("notifier struct"); 1763 np->next = *notif; 1764 np->func = func; 1765 np->arg = arg; 1766 *notif = np; 1767} 1768 1769/* 1770 * remove_notifier - remove a function from the list of things to 1771 * be called when something happens. 1772 */ 1773void 1774remove_notifier(notif, func, arg) 1775 struct notifier **notif; 1776 notify_func func; 1777 void *arg; 1778{ 1779 struct notifier *np; 1780 1781 for (; (np = *notif) != 0; notif = &np->next) { 1782 if (np->func == func && np->arg == arg) { 1783 *notif = np->next; 1784 free(np); 1785 break; 1786 } 1787 } 1788} 1789 1790/* 1791 * notify - call a set of functions registered with add_notifier. 1792 */ 1793void 1794notify(notif, val) 1795 struct notifier *notif; 1796 int val; 1797{ 1798 struct notifier *np; 1799 1800 while ((np = notif) != 0) { 1801 notif = np->next; 1802 (*np->func)(np->arg, val); 1803 } 1804} 1805 1806/* 1807 * novm - log an error message saying we ran out of memory, and die. 1808 */ 1809void 1810novm(msg) 1811 char *msg; 1812{ 1813 fatal("Virtual memory exhausted allocating %s\n", msg); 1814} 1815 1816/* 1817 * script_setenv - set an environment variable value to be used 1818 * for scripts that we run (e.g. ip-up, auth-up, etc.) 1819 */ 1820void 1821script_setenv(var, value, iskey) 1822 char *var, *value; 1823 int iskey; 1824{ 1825 size_t varl = strlen(var); 1826 size_t vl = varl + strlen(value) + 2; 1827 int i; 1828 char *p, *newstring; 1829 1830 newstring = (char *) malloc(vl+1); 1831 if (newstring == 0) 1832 return; 1833 *newstring++ = iskey; 1834 slprintf(newstring, vl, "%s=%s", var, value); 1835 1836 /* check if this variable is already set */ 1837 if (script_env != 0) { 1838 for (i = 0; (p = script_env[i]) != 0; ++i) { 1839 if (strncmp(p, var, varl) == 0 && p[varl] == '=') { 1840#ifdef USE_TDB 1841 if (p[-1] && pppdb != NULL) 1842 delete_db_key(p); 1843#endif 1844 free(p-1); 1845 script_env[i] = newstring; 1846#ifdef USE_TDB 1847 if (iskey && pppdb != NULL) 1848 add_db_key(newstring); 1849 update_db_entry(); 1850#endif 1851 return; 1852 } 1853 } 1854 } else { 1855 /* no space allocated for script env. ptrs. yet */ 1856 i = 0; 1857 script_env = (char **) malloc(16 * sizeof(char *)); 1858 if (script_env == 0) 1859 return; 1860 s_env_nalloc = 16; 1861 } 1862 1863 /* reallocate script_env with more space if needed */ 1864 if (i + 1 >= s_env_nalloc) { 1865 int new_n = i + 17; 1866 char **newenv = (char **) realloc((void *)script_env, 1867 new_n * sizeof(char *)); 1868 if (newenv == 0) 1869 return; 1870 script_env = newenv; 1871 s_env_nalloc = new_n; 1872 } 1873 1874 script_env[i] = newstring; 1875 script_env[i+1] = 0; 1876 1877#ifdef USE_TDB 1878 if (pppdb != NULL) { 1879 if (iskey) 1880 add_db_key(newstring); 1881 update_db_entry(); 1882 } 1883#endif 1884} 1885 1886/* 1887 * script_unsetenv - remove a variable from the environment 1888 * for scripts. 1889 */ 1890void 1891script_unsetenv(var) 1892 char *var; 1893{ 1894 int vl = strlen(var); 1895 int i; 1896 char *p; 1897 1898 if (script_env == 0) 1899 return; 1900 for (i = 0; (p = script_env[i]) != 0; ++i) { 1901 if (strncmp(p, var, vl) == 0 && p[vl] == '=') { 1902#ifdef USE_TDB 1903 if (p[-1] && pppdb != NULL) 1904 delete_db_key(p); 1905#endif 1906 free(p-1); 1907 while ((script_env[i] = script_env[i+1]) != 0) 1908 ++i; 1909 break; 1910 } 1911 } 1912#ifdef USE_TDB 1913 if (pppdb != NULL) 1914 update_db_entry(); 1915#endif 1916} 1917 1918#ifdef USE_TDB 1919/* 1920 * update_db_entry - update our entry in the database. 1921 */ 1922static void 1923update_db_entry() 1924{ 1925 TDB_DATA key, dbuf; 1926 int vlen, i; 1927 char *p, *q, *vbuf; 1928 1929 if (script_env == NULL) 1930 return; 1931 vlen = 0; 1932 for (i = 0; (p = script_env[i]) != 0; ++i) 1933 vlen += strlen(p) + 1; 1934 vbuf = malloc(vlen); 1935 if (vbuf == 0) 1936 novm("database entry"); 1937 q = vbuf; 1938 for (i = 0; (p = script_env[i]) != 0; ++i) 1939 q += slprintf(q, vbuf + vlen - q, "%s;", p); 1940 1941 key.dptr = db_key; 1942 key.dsize = strlen(db_key); 1943 dbuf.dptr = vbuf; 1944 dbuf.dsize = vlen; 1945 if (tdb_store(pppdb, key, dbuf, TDB_REPLACE)) 1946 error("tdb_store failed: %s", tdb_error(pppdb)); 1947 1948 if (vbuf) 1949 free(vbuf); 1950 1951} 1952 1953/* 1954 * add_db_key - add a key that we can use to look up our database entry. 1955 */ 1956static void 1957add_db_key(str) 1958 const char *str; 1959{ 1960 TDB_DATA key, dbuf; 1961 1962 key.dptr = (char *) str; 1963 key.dsize = strlen(str); 1964 dbuf.dptr = db_key; 1965 dbuf.dsize = strlen(db_key); 1966 if (tdb_store(pppdb, key, dbuf, TDB_REPLACE)) 1967 error("tdb_store key failed: %s", tdb_error(pppdb)); 1968} 1969 1970/* 1971 * delete_db_key - delete a key for looking up our database entry. 1972 */ 1973static void 1974delete_db_key(str) 1975 const char *str; 1976{ 1977 TDB_DATA key; 1978 1979 key.dptr = (char *) str; 1980 key.dsize = strlen(str); 1981 tdb_delete(pppdb, key); 1982} 1983 1984/* 1985 * cleanup_db - delete all the entries we put in the database. 1986 */ 1987static void 1988cleanup_db() 1989{ 1990 TDB_DATA key; 1991 int i; 1992 char *p; 1993 1994 key.dptr = db_key; 1995 key.dsize = strlen(db_key); 1996 tdb_delete(pppdb, key); 1997 for (i = 0; (p = script_env[i]) != 0; ++i) 1998 if (p[-1]) 1999 delete_db_key(p); 2000} 2001#endif /* USE_TDB */ 2002