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 (at) 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 * Copyright (c) 1999-2004 Paul Mackerras. All rights reserved. 43 * 44 * Redistribution and use in source and binary forms, with or without 45 * modification, are permitted provided that the following conditions 46 * are met: 47 * 48 * 1. Redistributions of source code must retain the above copyright 49 * notice, this list of conditions and the following disclaimer. 50 * 51 * 2. The name(s) of the authors of this software must not be used to 52 * endorse or promote products derived from this software without 53 * prior written permission. 54 * 55 * 3. Redistributions of any form whatsoever must retain the following 56 * acknowledgment: 57 * "This product includes software developed by Paul Mackerras 58 * <paulus (at) samba.org>". 59 * 60 * THE AUTHORS OF THIS SOFTWARE DISCLAIM ALL WARRANTIES WITH REGARD TO 61 * THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY 62 * AND FITNESS, IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY 63 * SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 64 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN 65 * AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING 66 * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 67 */ 68 69 #define RCSID "$Id: main.c,v 1.148 2004/11/13 12:05:48 paulus Exp $" 70 71 #include <stdio.h> 72 #include <ctype.h> 73 #include <stdlib.h> 74 #include <string.h> 75 #include <unistd.h> 76 #include <signal.h> 77 #include <errno.h> 78 #include <fcntl.h> 79 #include <syslog.h> 80 #include <netdb.h> 81 #include <utmp.h> 82 #include <pwd.h> 83 #include <setjmp.h> 84 #include <sys/param.h> 85 #include <sys/types.h> 86 #include <sys/wait.h> 87 #include <sys/time.h> 88 #include <sys/resource.h> 89 #include <sys/stat.h> 90 #include <sys/socket.h> 91 #include <netinet/in.h> 92 #include <arpa/inet.h> 93 #include <cutils/properties.h> 94 95 #include "pppd.h" 96 #include "magic.h" 97 #include "fsm.h" 98 #include "lcp.h" 99 #include "ipcp.h" 100 #ifdef INET6 101 #include "ipv6cp.h" 102 #endif 103 #include "upap.h" 104 #include "chap-new.h" 105 #include "eap.h" 106 #include "ccp.h" 107 #include "ecp.h" 108 #include "pathnames.h" 109 110 #ifdef USE_TDB 111 #include "tdb.h" 112 #endif 113 114 #ifdef CBCP_SUPPORT 115 #include "cbcp.h" 116 #endif 117 118 #ifdef IPX_CHANGE 119 #include "ipxcp.h" 120 #endif /* IPX_CHANGE */ 121 #ifdef AT_CHANGE 122 #include "atcp.h" 123 #endif 124 125 static const char rcsid[] = RCSID; 126 127 /* interface vars */ 128 char ifname[32]; /* Interface name */ 129 int ifunit; /* Interface unit number */ 130 131 struct channel *the_channel; 132 133 char *progname; /* Name of this program */ 134 char hostname[MAXNAMELEN]; /* Our hostname */ 135 static char pidfilename[MAXPATHLEN]; /* name of pid file */ 136 static char linkpidfile[MAXPATHLEN]; /* name of linkname pid file */ 137 char ppp_devnam[MAXPATHLEN]; /* name of PPP tty (maybe ttypx) */ 138 uid_t uid; /* Our real user-id */ 139 struct notifier *pidchange = NULL; 140 struct notifier *phasechange = NULL; 141 struct notifier *exitnotify = NULL; 142 struct notifier *sigreceived = NULL; 143 struct notifier *fork_notifier = NULL; 144 145 int hungup; /* terminal has been hung up */ 146 int privileged; /* we're running as real uid root */ 147 int need_holdoff; /* need holdoff period before restarting */ 148 int detached; /* have detached from terminal */ 149 volatile int status; /* exit status for pppd */ 150 int unsuccess; /* # unsuccessful connection attempts */ 151 int do_callback; /* != 0 if we should do callback next */ 152 int doing_callback; /* != 0 if we are doing callback */ 153 int ppp_session_number; /* Session number, for channels with such a 154 concept (eg PPPoE) */ 155 int childwait_done; /* have timed out waiting for children */ 156 157 #ifdef USE_TDB 158 TDB_CONTEXT *pppdb; /* database for storing status etc. */ 159 #endif 160 161 char db_key[32]; 162 163 int (*holdoff_hook) __P((void)) = NULL; 164 int (*new_phase_hook) __P((int)) = NULL; 165 void (*snoop_recv_hook) __P((unsigned char *p, int len)) = NULL; 166 void (*snoop_send_hook) __P((unsigned char *p, int len)) = NULL; 167 168 static int conn_running; /* we have a [dis]connector running */ 169 static int fd_loop; /* fd for getting demand-dial packets */ 170 171 int fd_devnull; /* fd for /dev/null */ 172 int devfd = -1; /* fd of underlying device */ 173 int fd_ppp = -1; /* fd for talking PPP */ 174 int phase; /* where the link is at */ 175 int kill_link; 176 int asked_to_quit; 177 int open_ccp_flag; 178 int listen_time; 179 int got_sigusr2; 180 int got_sigterm; 181 int got_sighup; 182 183 static sigset_t signals_handled; 184 static int waiting; 185 static sigjmp_buf sigjmp; 186 187 char **script_env; /* Env. variable values for scripts */ 188 int s_env_nalloc; /* # words avail at script_env */ 189 190 u_char outpacket_buf[PPP_MRU+PPP_HDRLEN]; /* buffer for outgoing packet */ 191 u_char inpacket_buf[PPP_MRU+PPP_HDRLEN]; /* buffer for incoming packet */ 192 193 static int n_children; /* # child processes still running */ 194 static int got_sigchld; /* set if we have received a SIGCHLD */ 195 196 int privopen; /* don't lock, open device as root */ 197 198 char *no_ppp_msg = "Sorry - this system lacks PPP kernel support\n"; 199 200 GIDSET_TYPE groups[NGROUPS_MAX];/* groups the user is in */ 201 int ngroups; /* How many groups valid in groups */ 202 203 static struct timeval start_time; /* Time when link was started. */ 204 205 static struct pppd_stats old_link_stats; 206 struct pppd_stats link_stats; 207 unsigned link_connect_time; 208 int link_stats_valid; 209 210 int error_count; 211 212 bool bundle_eof; 213 bool bundle_terminating; 214 215 int sent_since_received = 0; 216 int sent_total = 0; 217 int received_total = 0; 218 219 /* 220 * We maintain a list of child process pids and 221 * functions to call when they exit. 222 */ 223 struct subprocess { 224 pid_t pid; 225 char *prog; 226 void (*done) __P((void *)); 227 void *arg; 228 struct subprocess *next; 229 }; 230 231 static struct subprocess *children; 232 233 /* Prototypes for procedures local to this file. */ 234 235 static void setup_signals __P((void)); 236 static void create_pidfile __P((int pid)); 237 static void create_linkpidfile __P((int pid)); 238 static void cleanup __P((void)); 239 static void get_input __P((void)); 240 static void calltimeout __P((void)); 241 static struct timeval *timeleft __P((struct timeval *)); 242 static void kill_my_pg __P((int)); 243 static void hup __P((int)); 244 static void term __P((int)); 245 static void chld __P((int)); 246 static void toggle_debug __P((int)); 247 static void open_ccp __P((int)); 248 static void bad_signal __P((int)); 249 static void holdoff_end __P((void *)); 250 static int reap_kids __P((void)); 251 static void childwait_end __P((void *)); 252 253 #ifdef USE_TDB 254 static void update_db_entry __P((void)); 255 static void add_db_key __P((const char *)); 256 static void delete_db_key __P((const char *)); 257 static void cleanup_db __P((void)); 258 #endif 259 260 static void handle_events __P((void)); 261 void print_link_stats __P((void)); 262 263 extern char *ttyname __P((int)); 264 extern char *getlogin __P((void)); 265 int main __P((int, char *[])); 266 267 #ifdef ultrix 268 #undef O_NONBLOCK 269 #define O_NONBLOCK O_NDELAY 270 #endif 271 272 #ifdef ULTRIX 273 #define setlogmask(x) 274 #endif 275 276 /* 277 * PPP Data Link Layer "protocol" table. 278 * One entry per supported protocol. 279 * The last entry must be NULL. 280 */ 281 struct protent *protocols[] = { 282 &lcp_protent, 283 &pap_protent, 284 &chap_protent, 285 #ifdef CBCP_SUPPORT 286 &cbcp_protent, 287 #endif 288 &ipcp_protent, 289 #ifdef INET6 290 &ipv6cp_protent, 291 #endif 292 &ccp_protent, 293 &ecp_protent, 294 #ifdef IPX_CHANGE 295 &ipxcp_protent, 296 #endif 297 #ifdef AT_CHANGE 298 &atcp_protent, 299 #endif 300 &eap_protent, 301 NULL 302 }; 303 304 /* 305 * If PPP_DRV_NAME is not defined, use the default "ppp" as the device name. 306 */ 307 #if !defined(PPP_DRV_NAME) 308 #define PPP_DRV_NAME "ppp" 309 #endif /* !defined(PPP_DRV_NAME) */ 310 311 int 312 main(argc, argv) 313 int argc; 314 char *argv[]; 315 { 316 int i, t; 317 char *p; 318 struct passwd *pw; 319 struct protent *protp; 320 char numbuf[16]; 321 322 link_stats_valid = 0; 323 new_phase(PHASE_INITIALIZE); 324 325 script_env = NULL; 326 327 /* Initialize syslog facilities */ 328 reopen_log(); 329 330 if (gethostname(hostname, MAXNAMELEN) < 0 ) { 331 option_error("Couldn't get hostname: %m"); 332 exit(1); 333 } 334 hostname[MAXNAMELEN-1] = 0; 335 336 /* make sure we don't create world or group writable files. */ 337 umask(umask(0777) | 022); 338 339 uid = getuid(); 340 privileged = uid == 0; 341 slprintf(numbuf, sizeof(numbuf), "%d", uid); 342 script_setenv("ORIG_UID", numbuf, 0); 343 344 ngroups = getgroups(NGROUPS_MAX, groups); 345 346 /* 347 * Initialize magic number generator now so that protocols may 348 * use magic numbers in initialization. 349 */ 350 magic_init(); 351 352 /* 353 * Initialize each protocol. 354 */ 355 for (i = 0; (protp = protocols[i]) != NULL; ++i) 356 (*protp->init)(0); 357 358 /* 359 * Initialize the default channel. 360 */ 361 tty_init(); 362 363 progname = *argv; 364 365 #ifdef ANDROID_CHANGES 366 { 367 extern void pppox_init(); 368 pppox_init(); 369 privileged = 1; 370 } 371 { 372 char *envargs = getenv("envargs"); 373 if (envargs) { 374 int i; 375 /* Decode the arguments in-place and count the number of them. 376 * They were hex encoded using [A-P] instead of [0-9A-F]. */ 377 for (argc = 0, i = 0; envargs[i] && envargs[i + 1]; i += 2) { 378 char c = ((envargs[i] - 'A') << 4) + (envargs[i + 1] - 'A'); 379 if (c == 0) { 380 ++argc; 381 } 382 envargs[i / 2 + 1] = c; 383 } 384 if (argc == 0 || (argv = malloc(sizeof(char *) * argc)) == NULL) { 385 fatal("Failed to parse envargs!"); 386 } 387 for (envargs[0] = 0, i = 0; i < argc; ++envargs) { 388 if (envargs[0] == 0) { 389 argv[i++] = &envargs[1]; 390 } 391 } 392 } 393 } 394 #endif 395 396 /* 397 * Parse, in order, the system options file, the user's options file, 398 * and the command line arguments. 399 */ 400 #ifdef ANDROID_CHANGES 401 /* Android: only take options from commandline */ 402 if (!parse_args(argc-1, argv+1)) 403 exit(EXIT_OPTION_ERROR); 404 405 #else 406 if (!options_from_file(_PATH_SYSOPTIONS, !privileged, 0, 1) 407 || !options_from_user() 408 || !parse_args(argc-1, argv+1)) 409 exit(EXIT_OPTION_ERROR); 410 411 #endif 412 413 devnam_fixed = 1; /* can no longer change device name */ 414 415 /* 416 * Work out the device name, if it hasn't already been specified, 417 * and parse the tty's options file. 418 */ 419 if (the_channel->process_extra_options) 420 (*the_channel->process_extra_options)(); 421 422 if (debug) 423 setlogmask(LOG_UPTO(LOG_DEBUG)); 424 425 #ifndef ANDROID_CHANGES 426 /* 427 * Check that we are running as root. 428 */ 429 if (geteuid() != 0) { 430 option_error("must be root to run %s, since it is not setuid-root", 431 argv[0]); 432 exit(EXIT_NOT_ROOT); 433 } 434 #endif 435 436 if (!ppp_available()) { 437 option_error("%s", no_ppp_msg); 438 exit(EXIT_NO_KERNEL_SUPPORT); 439 } 440 441 /* 442 * Check that the options given are valid and consistent. 443 */ 444 check_options(); 445 if (!sys_check_options()) 446 exit(EXIT_OPTION_ERROR); 447 auth_check_options(); 448 #ifdef HAVE_MULTILINK 449 mp_check_options(); 450 #endif 451 for (i = 0; (protp = protocols[i]) != NULL; ++i) 452 if (protp->check_options != NULL) 453 (*protp->check_options)(); 454 if (the_channel->check_options) 455 (*the_channel->check_options)(); 456 457 458 if (dump_options || dryrun) { 459 init_pr_log(NULL, LOG_INFO); 460 print_options(pr_log, NULL); 461 end_pr_log(); 462 } 463 464 if (dryrun) 465 die(0); 466 467 /* Make sure fds 0, 1, 2 are open to somewhere. */ 468 fd_devnull = open(_PATH_DEVNULL, O_RDWR); 469 if (fd_devnull < 0) 470 fatal("Couldn't open %s: %m", _PATH_DEVNULL); 471 while (fd_devnull <= 2) { 472 i = dup(fd_devnull); 473 if (i < 0) 474 fatal("Critical shortage of file descriptors: dup failed: %m"); 475 fd_devnull = i; 476 } 477 478 /* 479 * Initialize system-dependent stuff. 480 */ 481 sys_init(); 482 #ifdef USE_TDB 483 pppdb = tdb_open(_PATH_PPPDB, 0, 0, O_RDWR|O_CREAT, 0644); 484 if (pppdb != NULL) { 485 slprintf(db_key, sizeof(db_key), "pppd%d", getpid()); 486 update_db_entry(); 487 } else { 488 warn("Warning: couldn't open ppp database %s", _PATH_PPPDB); 489 if (multilink) { 490 warn("Warning: disabling multilink"); 491 multilink = 0; 492 } 493 } 494 #endif 495 496 /* 497 * Detach ourselves from the terminal, if required, 498 * and identify who is running us. 499 */ 500 if (!nodetach && !updetach) 501 detach(); 502 p = getlogin(); 503 if (p == NULL) { 504 pw = getpwuid(uid); 505 if (pw != NULL && pw->pw_name != NULL) 506 p = pw->pw_name; 507 else 508 p = "(unknown)"; 509 } 510 syslog(LOG_NOTICE, "pppd %s started by %s, uid %d", VERSION, p, uid); 511 script_setenv("PPPLOGNAME", p, 0); 512 513 if (devnam[0]) 514 script_setenv("DEVICE", devnam, 1); 515 slprintf(numbuf, sizeof(numbuf), "%d", getpid()); 516 script_setenv("PPPD_PID", numbuf, 1); 517 518 setup_signals(); 519 520 create_linkpidfile(getpid()); 521 522 waiting = 0; 523 524 /* 525 * If we're doing dial-on-demand, set up the interface now. 526 */ 527 if (demand) { 528 /* 529 * Open the loopback channel and set it up to be the ppp interface. 530 */ 531 fd_loop = open_ppp_loopback(); 532 set_ifunit(1); 533 /* 534 * Configure the interface and mark it up, etc. 535 */ 536 demand_conf(); 537 } 538 539 do_callback = 0; 540 for (;;) { 541 542 bundle_eof = 0; 543 bundle_terminating = 0; 544 listen_time = 0; 545 need_holdoff = 1; 546 devfd = -1; 547 status = EXIT_OK; 548 ++unsuccess; 549 doing_callback = do_callback; 550 do_callback = 0; 551 552 if (demand && !doing_callback) { 553 /* 554 * Don't do anything until we see some activity. 555 */ 556 new_phase(PHASE_DORMANT); 557 demand_unblock(); 558 add_fd(fd_loop); 559 for (;;) { 560 handle_events(); 561 if (asked_to_quit) 562 break; 563 if (get_loop_output()) 564 break; 565 } 566 remove_fd(fd_loop); 567 if (asked_to_quit) 568 break; 569 570 /* 571 * Now we want to bring up the link. 572 */ 573 demand_block(); 574 info("Starting link"); 575 } 576 577 gettimeofday(&start_time, NULL); 578 script_unsetenv("CONNECT_TIME"); 579 script_unsetenv("BYTES_SENT"); 580 script_unsetenv("BYTES_RCVD"); 581 582 lcp_open(0); /* Start protocol */ 583 while (phase != PHASE_DEAD) { 584 handle_events(); 585 get_input(); 586 if (kill_link) 587 lcp_close(0, "User request"); 588 if (asked_to_quit) { 589 bundle_terminating = 1; 590 if (phase == PHASE_MASTER) 591 mp_bundle_terminated(); 592 } 593 if (open_ccp_flag) { 594 if (phase == PHASE_NETWORK || phase == PHASE_RUNNING) { 595 ccp_fsm[0].flags = OPT_RESTART; /* clears OPT_SILENT */ 596 (*ccp_protent.open)(0); 597 } 598 } 599 } 600 601 if (!persist || asked_to_quit || (maxfail > 0 && unsuccess >= maxfail)) 602 break; 603 604 if (demand) 605 demand_discard(); 606 t = need_holdoff? holdoff: 0; 607 if (holdoff_hook) 608 t = (*holdoff_hook)(); 609 if (t > 0) { 610 new_phase(PHASE_HOLDOFF); 611 TIMEOUT(holdoff_end, NULL, t); 612 do { 613 handle_events(); 614 if (kill_link) 615 new_phase(PHASE_DORMANT); /* allow signal to end holdoff */ 616 } while (phase == PHASE_HOLDOFF); 617 if (!persist) 618 break; 619 } 620 } 621 622 /* Wait for scripts to finish */ 623 reap_kids(); 624 if (n_children > 0) { 625 if (child_wait > 0) 626 TIMEOUT(childwait_end, NULL, child_wait); 627 if (debug) { 628 struct subprocess *chp; 629 dbglog("Waiting for %d child processes...", n_children); 630 for (chp = children; chp != NULL; chp = chp->next) 631 dbglog(" script %s, pid %d", chp->prog, chp->pid); 632 } 633 while (n_children > 0 && !childwait_done) { 634 handle_events(); 635 if (kill_link && !childwait_done) 636 childwait_end(NULL); 637 } 638 } 639 640 die(status); 641 return 0; 642 } 643 644 /* 645 * handle_events - wait for something to happen and respond to it. 646 */ 647 static void 648 handle_events() 649 { 650 struct timeval timo; 651 652 kill_link = open_ccp_flag = 0; 653 if (sigsetjmp(sigjmp, 1) == 0) { 654 sigprocmask(SIG_BLOCK, &signals_handled, NULL); 655 if (got_sighup || got_sigterm || got_sigusr2 || got_sigchld) { 656 sigprocmask(SIG_UNBLOCK, &signals_handled, NULL); 657 } else { 658 waiting = 1; 659 sigprocmask(SIG_UNBLOCK, &signals_handled, NULL); 660 wait_input(timeleft(&timo)); 661 } 662 } 663 waiting = 0; 664 calltimeout(); 665 if (got_sighup) { 666 info("Hangup (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 info("Terminating on signal %d", got_sigterm); 674 kill_link = 1; 675 asked_to_quit = 1; 676 persist = 0; 677 status = EXIT_USER_REQUEST; 678 got_sigterm = 0; 679 } 680 if (got_sigchld) { 681 got_sigchld = 0; 682 reap_kids(); /* Don't leave dead kids lying around */ 683 } 684 if (got_sigusr2) { 685 open_ccp_flag = 1; 686 got_sigusr2 = 0; 687 } 688 } 689 690 /* 691 * setup_signals - initialize signal handling. 692 */ 693 static void 694 setup_signals() 695 { 696 struct sigaction sa; 697 698 /* 699 * Compute mask of all interesting signals and install signal handlers 700 * for each. Only one signal handler may be active at a time. Therefore, 701 * all other signals should be masked when any handler is executing. 702 */ 703 sigemptyset(&signals_handled); 704 sigaddset(&signals_handled, SIGHUP); 705 sigaddset(&signals_handled, SIGINT); 706 sigaddset(&signals_handled, SIGTERM); 707 sigaddset(&signals_handled, SIGCHLD); 708 sigaddset(&signals_handled, SIGUSR2); 709 710 #define SIGNAL(s, handler) do { \ 711 sa.sa_handler = handler; \ 712 if (sigaction(s, &sa, NULL) < 0) \ 713 fatal("Couldn't establish signal handler (%d): %m", s); \ 714 } while (0) 715 716 sa.sa_mask = signals_handled; 717 sa.sa_flags = 0; 718 SIGNAL(SIGHUP, hup); /* Hangup */ 719 SIGNAL(SIGINT, term); /* Interrupt */ 720 SIGNAL(SIGTERM, term); /* Terminate */ 721 SIGNAL(SIGCHLD, chld); 722 723 SIGNAL(SIGUSR1, toggle_debug); /* Toggle debug flag */ 724 SIGNAL(SIGUSR2, open_ccp); /* Reopen CCP */ 725 726 /* 727 * Install a handler for other signals which would otherwise 728 * cause pppd to exit without cleaning up. 729 */ 730 SIGNAL(SIGABRT, bad_signal); 731 SIGNAL(SIGALRM, bad_signal); 732 SIGNAL(SIGFPE, bad_signal); 733 SIGNAL(SIGILL, bad_signal); 734 SIGNAL(SIGPIPE, bad_signal); 735 SIGNAL(SIGQUIT, bad_signal); 736 SIGNAL(SIGSEGV, bad_signal); 737 #ifdef SIGBUS 738 SIGNAL(SIGBUS, bad_signal); 739 #endif 740 #ifdef SIGEMT 741 SIGNAL(SIGEMT, bad_signal); 742 #endif 743 #ifdef SIGPOLL 744 SIGNAL(SIGPOLL, bad_signal); 745 #endif 746 #ifdef SIGPROF 747 SIGNAL(SIGPROF, bad_signal); 748 #endif 749 #ifdef SIGSYS 750 SIGNAL(SIGSYS, bad_signal); 751 #endif 752 #ifdef SIGTRAP 753 SIGNAL(SIGTRAP, bad_signal); 754 #endif 755 #ifdef SIGVTALRM 756 SIGNAL(SIGVTALRM, bad_signal); 757 #endif 758 #ifdef SIGXCPU 759 SIGNAL(SIGXCPU, bad_signal); 760 #endif 761 #ifdef SIGXFSZ 762 SIGNAL(SIGXFSZ, bad_signal); 763 #endif 764 765 /* 766 * Apparently we can get a SIGPIPE when we call syslog, if 767 * syslogd has died and been restarted. Ignoring it seems 768 * be sufficient. 769 */ 770 signal(SIGPIPE, SIG_IGN); 771 } 772 773 /* 774 * set_ifunit - do things we need to do once we know which ppp 775 * unit we are using. 776 */ 777 void 778 set_ifunit(iskey) 779 int iskey; 780 { 781 info("Using interface %s%d", PPP_DRV_NAME, ifunit); 782 slprintf(ifname, sizeof(ifname), "%s%d", PPP_DRV_NAME, ifunit); 783 script_setenv("IFNAME", ifname, iskey); 784 if (iskey) { 785 create_pidfile(getpid()); /* write pid to file */ 786 create_linkpidfile(getpid()); 787 } 788 } 789 790 /* 791 * detach - detach us from the controlling terminal. 792 */ 793 void 794 detach() 795 { 796 int pid; 797 char numbuf[16]; 798 int pipefd[2]; 799 800 if (detached) 801 return; 802 if (pipe(pipefd) == -1) 803 pipefd[0] = pipefd[1] = -1; 804 if ((pid = fork()) < 0) { 805 error("Couldn't detach (fork failed: %m)"); 806 die(1); /* or just return? */ 807 } 808 if (pid != 0) { 809 /* parent */ 810 notify(pidchange, pid); 811 /* update pid files if they have been written already */ 812 if (pidfilename[0]) 813 create_pidfile(pid); 814 if (linkpidfile[0]) 815 create_linkpidfile(pid); 816 exit(0); /* parent dies */ 817 } 818 setsid(); 819 chdir("/"); 820 dup2(fd_devnull, 0); 821 dup2(fd_devnull, 1); 822 dup2(fd_devnull, 2); 823 detached = 1; 824 if (log_default) 825 log_to_fd = -1; 826 slprintf(numbuf, sizeof(numbuf), "%d", getpid()); 827 script_setenv("PPPD_PID", numbuf, 1); 828 829 /* wait for parent to finish updating pid & lock files and die */ 830 close(pipefd[1]); 831 complete_read(pipefd[0], numbuf, 1); 832 close(pipefd[0]); 833 } 834 835 /* 836 * reopen_log - (re)open our connection to syslog. 837 */ 838 void 839 reopen_log() 840 { 841 #ifndef ANDROID_CHANGES 842 openlog("pppd", LOG_PID | LOG_NDELAY, LOG_PPP); 843 setlogmask(LOG_UPTO(LOG_INFO)); 844 #endif 845 } 846 847 /* 848 * Create a file containing our process ID. 849 */ 850 static void 851 create_pidfile(pid) 852 int pid; 853 { 854 #ifndef ANDROID_CHANGES 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 #endif 867 } 868 869 void 870 create_linkpidfile(pid) 871 int pid; 872 { 873 #ifndef ANDROID_CHANGES 874 FILE *pidfile; 875 876 if (linkname[0] == 0) 877 return; 878 script_setenv("LINKNAME", linkname, 1); 879 slprintf(linkpidfile, sizeof(linkpidfile), "%sppp-%s.pid", 880 _PATH_VARRUN, linkname); 881 if ((pidfile = fopen(linkpidfile, "w")) != NULL) { 882 fprintf(pidfile, "%d\n", pid); 883 if (ifname[0]) 884 fprintf(pidfile, "%s\n", ifname); 885 (void) fclose(pidfile); 886 } else { 887 error("Failed to create pid file %s: %m", linkpidfile); 888 linkpidfile[0] = 0; 889 } 890 #endif 891 } 892 893 /* 894 * remove_pidfile - remove our pid files 895 */ 896 void remove_pidfiles() 897 { 898 #ifndef ANDROID_CHANGES 899 if (pidfilename[0] != 0 && unlink(pidfilename) < 0 && errno != ENOENT) 900 warn("unable to delete pid file %s: %m", pidfilename); 901 pidfilename[0] = 0; 902 if (linkpidfile[0] != 0 && unlink(linkpidfile) < 0 && errno != ENOENT) 903 warn("unable to delete pid file %s: %m", linkpidfile); 904 linkpidfile[0] = 0; 905 #endif 906 } 907 908 /* 909 * holdoff_end - called via a timeout when the holdoff period ends. 910 */ 911 static void 912 holdoff_end(arg) 913 void *arg; 914 { 915 new_phase(PHASE_DORMANT); 916 } 917 918 /* List of protocol names, to make our messages a little more informative. */ 919 struct protocol_list { 920 u_short proto; 921 const char *name; 922 } protocol_list[] = { 923 { 0x21, "IP" }, 924 { 0x23, "OSI Network Layer" }, 925 { 0x25, "Xerox NS IDP" }, 926 { 0x27, "DECnet Phase IV" }, 927 { 0x29, "Appletalk" }, 928 { 0x2b, "Novell IPX" }, 929 { 0x2d, "VJ compressed TCP/IP" }, 930 { 0x2f, "VJ uncompressed TCP/IP" }, 931 { 0x31, "Bridging PDU" }, 932 { 0x33, "Stream Protocol ST-II" }, 933 { 0x35, "Banyan Vines" }, 934 { 0x39, "AppleTalk EDDP" }, 935 { 0x3b, "AppleTalk SmartBuffered" }, 936 { 0x3d, "Multi-Link" }, 937 { 0x3f, "NETBIOS Framing" }, 938 { 0x41, "Cisco Systems" }, 939 { 0x43, "Ascom Timeplex" }, 940 { 0x45, "Fujitsu Link Backup and Load Balancing (LBLB)" }, 941 { 0x47, "DCA Remote Lan" }, 942 { 0x49, "Serial Data Transport Protocol (PPP-SDTP)" }, 943 { 0x4b, "SNA over 802.2" }, 944 { 0x4d, "SNA" }, 945 { 0x4f, "IP6 Header Compression" }, 946 { 0x6f, "Stampede Bridging" }, 947 { 0xfb, "single-link compression" }, 948 { 0xfd, "1st choice compression" }, 949 { 0x0201, "802.1d Hello Packets" }, 950 { 0x0203, "IBM Source Routing BPDU" }, 951 { 0x0205, "DEC LANBridge100 Spanning Tree" }, 952 { 0x0231, "Luxcom" }, 953 { 0x0233, "Sigma Network Systems" }, 954 { 0x8021, "Internet Protocol Control Protocol" }, 955 { 0x8023, "OSI Network Layer Control Protocol" }, 956 { 0x8025, "Xerox NS IDP Control Protocol" }, 957 { 0x8027, "DECnet Phase IV Control Protocol" }, 958 { 0x8029, "Appletalk Control Protocol" }, 959 { 0x802b, "Novell IPX Control Protocol" }, 960 { 0x8031, "Bridging NCP" }, 961 { 0x8033, "Stream Protocol Control Protocol" }, 962 { 0x8035, "Banyan Vines Control Protocol" }, 963 { 0x803d, "Multi-Link Control Protocol" }, 964 { 0x803f, "NETBIOS Framing Control Protocol" }, 965 { 0x8041, "Cisco Systems Control Protocol" }, 966 { 0x8043, "Ascom Timeplex" }, 967 { 0x8045, "Fujitsu LBLB Control Protocol" }, 968 { 0x8047, "DCA Remote Lan Network Control Protocol (RLNCP)" }, 969 { 0x8049, "Serial Data Control Protocol (PPP-SDCP)" }, 970 { 0x804b, "SNA over 802.2 Control Protocol" }, 971 { 0x804d, "SNA Control Protocol" }, 972 { 0x804f, "IP6 Header Compression Control Protocol" }, 973 { 0x006f, "Stampede Bridging Control Protocol" }, 974 { 0x80fb, "Single Link Compression Control Protocol" }, 975 { 0x80fd, "Compression Control Protocol" }, 976 { 0xc021, "Link Control Protocol" }, 977 { 0xc023, "Password Authentication Protocol" }, 978 { 0xc025, "Link Quality Report" }, 979 { 0xc027, "Shiva Password Authentication Protocol" }, 980 { 0xc029, "CallBack Control Protocol (CBCP)" }, 981 { 0xc081, "Container Control Protocol" }, 982 { 0xc223, "Challenge Handshake Authentication Protocol" }, 983 { 0xc281, "Proprietary Authentication Protocol" }, 984 { 0, NULL }, 985 }; 986 987 /* 988 * protocol_name - find a name for a PPP protocol. 989 */ 990 const char * 991 protocol_name(proto) 992 int proto; 993 { 994 struct protocol_list *lp; 995 996 for (lp = protocol_list; lp->proto != 0; ++lp) 997 if (proto == lp->proto) 998 return lp->name; 999 return NULL; 1000 } 1001 1002 /* 1003 * get_input - called when incoming data is available. 1004 */ 1005 static void 1006 get_input() 1007 { 1008 int len, i; 1009 u_char *p; 1010 u_short protocol; 1011 struct protent *protp; 1012 1013 p = inpacket_buf; /* point to beginning of packet buffer */ 1014 1015 len = read_packet(inpacket_buf); 1016 if (len < 0) 1017 return; 1018 1019 if (len == 0) { 1020 if (bundle_eof && multilink_master) { 1021 notice("Last channel has disconnected"); 1022 mp_bundle_terminated(); 1023 return; 1024 } 1025 notice("Modem hangup"); 1026 hungup = 1; 1027 status = EXIT_HANGUP; 1028 lcp_lowerdown(0); /* serial link is no longer available */ 1029 link_terminated(0); 1030 return; 1031 } 1032 1033 if (len < PPP_HDRLEN) { 1034 dbglog("received short packet:%.*B", len, p); 1035 return; 1036 } 1037 1038 dump_packet("rcvd", p, len); 1039 if (snoop_recv_hook) snoop_recv_hook(p, len); 1040 1041 p += 2; /* Skip address and control */ 1042 GETSHORT(protocol, p); 1043 len -= PPP_HDRLEN; 1044 1045 /* 1046 * Toss all non-LCP packets unless LCP is OPEN. 1047 */ 1048 if (protocol != PPP_LCP && lcp_fsm[0].state != OPENED) { 1049 dbglog("Discarded non-LCP packet when LCP not open"); 1050 return; 1051 } 1052 1053 /* 1054 * Until we get past the authentication phase, toss all packets 1055 * except LCP, LQR and authentication packets. 1056 */ 1057 if (phase <= PHASE_AUTHENTICATE 1058 && !(protocol == PPP_LCP || protocol == PPP_LQR 1059 || protocol == PPP_PAP || protocol == PPP_CHAP || 1060 protocol == PPP_EAP)) { 1061 dbglog("discarding proto 0x%x in phase %d", 1062 protocol, phase); 1063 return; 1064 } 1065 1066 /* 1067 * Upcall the proper protocol input routine. 1068 */ 1069 for (i = 0; (protp = protocols[i]) != NULL; ++i) { 1070 if (protp->protocol == protocol && protp->enabled_flag) { 1071 (*protp->input)(0, p, len); 1072 return; 1073 } 1074 if (protocol == (protp->protocol & ~0x8000) && protp->enabled_flag 1075 && protp->datainput != NULL) { 1076 (*protp->datainput)(0, p, len); 1077 return; 1078 } 1079 } 1080 1081 if (debug) { 1082 const char *pname = protocol_name(protocol); 1083 if (pname != NULL) 1084 warn("Unsupported protocol '%s' (0x%x) received", pname, protocol); 1085 else 1086 warn("Unsupported protocol 0x%x received", protocol); 1087 } 1088 lcp_sprotrej(0, p - PPP_HDRLEN, len + PPP_HDRLEN); 1089 } 1090 1091 /* 1092 * ppp_send_config - configure the transmit-side characteristics of 1093 * the ppp interface. Returns -1, indicating an error, if the channel 1094 * send_config procedure called error() (or incremented error_count 1095 * itself), otherwise 0. 1096 */ 1097 int 1098 ppp_send_config(unit, mtu, accm, pcomp, accomp) 1099 int unit, mtu; 1100 u_int32_t accm; 1101 int pcomp, accomp; 1102 { 1103 int errs; 1104 1105 if (the_channel->send_config == NULL) 1106 return 0; 1107 errs = error_count; 1108 (*the_channel->send_config)(mtu, accm, pcomp, accomp); 1109 return (error_count != errs)? -1: 0; 1110 } 1111 1112 /* 1113 * ppp_recv_config - configure the receive-side characteristics of 1114 * the ppp interface. Returns -1, indicating an error, if the channel 1115 * recv_config procedure called error() (or incremented error_count 1116 * itself), otherwise 0. 1117 */ 1118 int 1119 ppp_recv_config(unit, mru, accm, pcomp, accomp) 1120 int unit, mru; 1121 u_int32_t accm; 1122 int pcomp, accomp; 1123 { 1124 int errs; 1125 1126 if (the_channel->recv_config == NULL) 1127 return 0; 1128 errs = error_count; 1129 (*the_channel->recv_config)(mru, accm, pcomp, accomp); 1130 return (error_count != errs)? -1: 0; 1131 } 1132 1133 /* 1134 * new_phase - signal the start of a new phase of pppd's operation. 1135 */ 1136 void 1137 new_phase(p) 1138 int p; 1139 { 1140 phase = p; 1141 if (new_phase_hook) 1142 (*new_phase_hook)(p); 1143 notify(phasechange, p); 1144 } 1145 1146 /* 1147 * die - clean up state and exit with the specified status. 1148 */ 1149 void 1150 die(status) 1151 int status; 1152 { 1153 if (!doing_multilink || multilink_master) 1154 print_link_stats(); 1155 cleanup(); 1156 notify(exitnotify, status); 1157 syslog(LOG_INFO, "Exit."); 1158 exit(status); 1159 } 1160 1161 /* 1162 * cleanup - restore anything which needs to be restored before we exit 1163 */ 1164 /* ARGSUSED */ 1165 static void 1166 cleanup() 1167 { 1168 sys_cleanup(); 1169 1170 if (fd_ppp >= 0) 1171 the_channel->disestablish_ppp(devfd); 1172 if (the_channel->cleanup) 1173 (*the_channel->cleanup)(); 1174 remove_pidfiles(); 1175 1176 #ifdef USE_TDB 1177 if (pppdb != NULL) 1178 cleanup_db(); 1179 #endif 1180 1181 } 1182 1183 void 1184 print_link_stats() 1185 { 1186 /* 1187 * Print connect time and statistics. 1188 */ 1189 if (link_stats_valid) { 1190 int t = (link_connect_time + 5) / 6; /* 1/10ths of minutes */ 1191 info("Connect time %d.%d minutes.", t/10, t%10); 1192 info("Sent %u bytes, received %u bytes.", 1193 link_stats.bytes_out, link_stats.bytes_in); 1194 link_stats_valid = 0; 1195 } 1196 } 1197 1198 /* 1199 * reset_link_stats - "reset" stats when link goes up. 1200 */ 1201 void 1202 reset_link_stats(u) 1203 int u; 1204 { 1205 if (!get_ppp_stats(u, &old_link_stats)) 1206 return; 1207 gettimeofday(&start_time, NULL); 1208 } 1209 1210 /* 1211 * update_link_stats - get stats at link termination. 1212 */ 1213 void 1214 update_link_stats(u) 1215 int u; 1216 { 1217 struct timeval now; 1218 char numbuf[32]; 1219 1220 if (!get_ppp_stats(u, &link_stats) 1221 || gettimeofday(&now, NULL) < 0) 1222 return; 1223 link_connect_time = now.tv_sec - start_time.tv_sec; 1224 link_stats_valid = 1; 1225 1226 link_stats.bytes_in -= old_link_stats.bytes_in; 1227 link_stats.bytes_out -= old_link_stats.bytes_out; 1228 link_stats.pkts_in -= old_link_stats.pkts_in; 1229 link_stats.pkts_out -= old_link_stats.pkts_out; 1230 1231 slprintf(numbuf, sizeof(numbuf), "%u", link_connect_time); 1232 script_setenv("CONNECT_TIME", numbuf, 0); 1233 slprintf(numbuf, sizeof(numbuf), "%u", link_stats.bytes_out); 1234 script_setenv("BYTES_SENT", numbuf, 0); 1235 slprintf(numbuf, sizeof(numbuf), "%u", link_stats.bytes_in); 1236 script_setenv("BYTES_RCVD", numbuf, 0); 1237 } 1238 1239 1240 struct callout { 1241 struct timeval c_time; /* time at which to call routine */ 1242 void *c_arg; /* argument to routine */ 1243 void (*c_func) __P((void *)); /* routine */ 1244 struct callout *c_next; 1245 }; 1246 1247 static struct callout *callout = NULL; /* Callout list */ 1248 static struct timeval timenow; /* Current time */ 1249 1250 /* 1251 * timeout - Schedule a timeout. 1252 */ 1253 void 1254 timeout(func, arg, secs, usecs) 1255 void (*func) __P((void *)); 1256 void *arg; 1257 int secs, usecs; 1258 { 1259 struct callout *newp, *p, **pp; 1260 1261 /* 1262 * Allocate timeout. 1263 */ 1264 if ((newp = (struct callout *) malloc(sizeof(struct callout))) == NULL) 1265 fatal("Out of memory in timeout()!"); 1266 newp->c_arg = arg; 1267 newp->c_func = func; 1268 gettimeofday(&timenow, NULL); 1269 newp->c_time.tv_sec = timenow.tv_sec + secs; 1270 newp->c_time.tv_usec = timenow.tv_usec + usecs; 1271 if (newp->c_time.tv_usec >= 1000000) { 1272 newp->c_time.tv_sec += newp->c_time.tv_usec / 1000000; 1273 newp->c_time.tv_usec %= 1000000; 1274 } 1275 1276 /* 1277 * Find correct place and link it in. 1278 */ 1279 for (pp = &callout; (p = *pp); pp = &p->c_next) 1280 if (newp->c_time.tv_sec < p->c_time.tv_sec 1281 || (newp->c_time.tv_sec == p->c_time.tv_sec 1282 && newp->c_time.tv_usec < p->c_time.tv_usec)) 1283 break; 1284 newp->c_next = p; 1285 *pp = newp; 1286 } 1287 1288 1289 /* 1290 * untimeout - Unschedule a timeout. 1291 */ 1292 void 1293 untimeout(func, arg) 1294 void (*func) __P((void *)); 1295 void *arg; 1296 { 1297 struct callout **copp, *freep; 1298 1299 /* 1300 * Find first matching timeout and remove it from the list. 1301 */ 1302 for (copp = &callout; (freep = *copp); copp = &freep->c_next) 1303 if (freep->c_func == func && freep->c_arg == arg) { 1304 *copp = freep->c_next; 1305 free((char *) freep); 1306 break; 1307 } 1308 } 1309 1310 1311 /* 1312 * calltimeout - Call any timeout routines which are now due. 1313 */ 1314 static void 1315 calltimeout() 1316 { 1317 struct callout *p; 1318 1319 while (callout != NULL) { 1320 p = callout; 1321 1322 if (gettimeofday(&timenow, NULL) < 0) 1323 fatal("Failed to get time of day: %m"); 1324 if (!(p->c_time.tv_sec < timenow.tv_sec 1325 || (p->c_time.tv_sec == timenow.tv_sec 1326 && p->c_time.tv_usec <= timenow.tv_usec))) 1327 break; /* no, it's not time yet */ 1328 1329 callout = p->c_next; 1330 (*p->c_func)(p->c_arg); 1331 1332 free((char *) p); 1333 } 1334 } 1335 1336 1337 /* 1338 * timeleft - return the length of time until the next timeout is due. 1339 */ 1340 static struct timeval * 1341 timeleft(tvp) 1342 struct timeval *tvp; 1343 { 1344 if (callout == NULL) 1345 return NULL; 1346 1347 gettimeofday(&timenow, NULL); 1348 tvp->tv_sec = callout->c_time.tv_sec - timenow.tv_sec; 1349 tvp->tv_usec = callout->c_time.tv_usec - timenow.tv_usec; 1350 if (tvp->tv_usec < 0) { 1351 tvp->tv_usec += 1000000; 1352 tvp->tv_sec -= 1; 1353 } 1354 if (tvp->tv_sec < 0) 1355 tvp->tv_sec = tvp->tv_usec = 0; 1356 1357 return tvp; 1358 } 1359 1360 1361 /* 1362 * kill_my_pg - send a signal to our process group, and ignore it ourselves. 1363 * We assume that sig is currently blocked. 1364 */ 1365 static void 1366 kill_my_pg(sig) 1367 int sig; 1368 { 1369 struct sigaction act, oldact; 1370 1371 sigemptyset(&act.sa_mask); /* unnecessary in fact */ 1372 act.sa_handler = SIG_IGN; 1373 act.sa_flags = 0; 1374 kill(0, sig); 1375 /* 1376 * The kill() above made the signal pending for us, as well as 1377 * the rest of our process group, but we don't want it delivered 1378 * to us. It is blocked at the moment. Setting it to be ignored 1379 * will cause the pending signal to be discarded. If we did the 1380 * kill() after setting the signal to be ignored, it is unspecified 1381 * (by POSIX) whether the signal is immediately discarded or left 1382 * pending, and in fact Linux would leave it pending, and so it 1383 * would be delivered after the current signal handler exits, 1384 * leading to an infinite loop. 1385 */ 1386 sigaction(sig, &act, &oldact); 1387 sigaction(sig, &oldact, NULL); 1388 } 1389 1390 1391 /* 1392 * hup - Catch SIGHUP signal. 1393 * 1394 * Indicates that the physical layer has been disconnected. 1395 * We don't rely on this indication; if the user has sent this 1396 * signal, we just take the link down. 1397 */ 1398 static void 1399 hup(sig) 1400 int sig; 1401 { 1402 /* can't log a message here, it can deadlock */ 1403 got_sighup = 1; 1404 if (conn_running) 1405 /* Send the signal to the [dis]connector process(es) also */ 1406 kill_my_pg(sig); 1407 notify(sigreceived, sig); 1408 if (waiting) 1409 siglongjmp(sigjmp, 1); 1410 } 1411 1412 1413 /* 1414 * term - Catch SIGTERM signal and SIGINT signal (^C/del). 1415 * 1416 * Indicates that we should initiate a graceful disconnect and exit. 1417 */ 1418 /*ARGSUSED*/ 1419 static void 1420 term(sig) 1421 int sig; 1422 { 1423 /* can't log a message here, it can deadlock */ 1424 got_sigterm = sig; 1425 if (conn_running) 1426 /* Send the signal to the [dis]connector process(es) also */ 1427 kill_my_pg(sig); 1428 notify(sigreceived, sig); 1429 if (waiting) 1430 siglongjmp(sigjmp, 1); 1431 } 1432 1433 1434 /* 1435 * chld - Catch SIGCHLD signal. 1436 * Sets a flag so we will call reap_kids in the mainline. 1437 */ 1438 static void 1439 chld(sig) 1440 int sig; 1441 { 1442 got_sigchld = 1; 1443 if (waiting) 1444 siglongjmp(sigjmp, 1); 1445 } 1446 1447 1448 /* 1449 * toggle_debug - Catch SIGUSR1 signal. 1450 * 1451 * Toggle debug flag. 1452 */ 1453 /*ARGSUSED*/ 1454 static void 1455 toggle_debug(sig) 1456 int sig; 1457 { 1458 debug = !debug; 1459 if (debug) { 1460 setlogmask(LOG_UPTO(LOG_DEBUG)); 1461 } else { 1462 setlogmask(LOG_UPTO(LOG_WARNING)); 1463 } 1464 } 1465 1466 1467 /* 1468 * open_ccp - Catch SIGUSR2 signal. 1469 * 1470 * Try to (re)negotiate compression. 1471 */ 1472 /*ARGSUSED*/ 1473 static void 1474 open_ccp(sig) 1475 int sig; 1476 { 1477 got_sigusr2 = 1; 1478 if (waiting) 1479 siglongjmp(sigjmp, 1); 1480 } 1481 1482 1483 /* 1484 * bad_signal - We've caught a fatal signal. Clean up state and exit. 1485 */ 1486 static void 1487 bad_signal(sig) 1488 int sig; 1489 { 1490 static int crashed = 0; 1491 1492 if (crashed) 1493 _exit(127); 1494 crashed = 1; 1495 error("Fatal signal %d", sig); 1496 if (conn_running) 1497 kill_my_pg(SIGTERM); 1498 notify(sigreceived, sig); 1499 die(127); 1500 } 1501 1502 /* 1503 * safe_fork - Create a child process. The child closes all the 1504 * file descriptors that we don't want to leak to a script. 1505 * The parent waits for the child to do this before returning. 1506 * This also arranges for the specified fds to be dup'd to 1507 * fds 0, 1, 2 in the child. 1508 */ 1509 pid_t 1510 safe_fork(int infd, int outfd, int errfd) 1511 { 1512 pid_t pid; 1513 int fd, pipefd[2]; 1514 char buf[1]; 1515 1516 /* make sure fds 0, 1, 2 are occupied (probably not necessary) */ 1517 while ((fd = dup(fd_devnull)) >= 0) { 1518 if (fd > 2) { 1519 close(fd); 1520 break; 1521 } 1522 } 1523 1524 if (pipe(pipefd) == -1) 1525 pipefd[0] = pipefd[1] = -1; 1526 pid = fork(); 1527 if (pid < 0) { 1528 error("fork failed: %m"); 1529 return -1; 1530 } 1531 if (pid > 0) { 1532 /* parent */ 1533 close(pipefd[1]); 1534 /* this read() blocks until the close(pipefd[1]) below */ 1535 complete_read(pipefd[0], buf, 1); 1536 close(pipefd[0]); 1537 return pid; 1538 } 1539 1540 /* Executing in the child */ 1541 sys_close(); 1542 #ifdef USE_TDB 1543 tdb_close(pppdb); 1544 #endif 1545 1546 /* make sure infd, outfd and errfd won't get tromped on below */ 1547 if (infd == 1 || infd == 2) 1548 infd = dup(infd); 1549 if (outfd == 0 || outfd == 2) 1550 outfd = dup(outfd); 1551 if (errfd == 0 || errfd == 1) 1552 errfd = dup(errfd); 1553 1554 /* dup the in, out, err fds to 0, 1, 2 */ 1555 if (infd != 0) 1556 dup2(infd, 0); 1557 if (outfd != 1) 1558 dup2(outfd, 1); 1559 if (errfd != 2) 1560 dup2(errfd, 2); 1561 1562 #ifndef ANDROID_CHANGES 1563 closelog(); 1564 #endif 1565 if (log_to_fd > 2) 1566 close(log_to_fd); 1567 if (the_channel->close) 1568 (*the_channel->close)(); 1569 else 1570 close(devfd); /* some plugins don't have a close function */ 1571 close(fd_ppp); 1572 close(fd_devnull); 1573 if (infd != 0) 1574 close(infd); 1575 if (outfd != 1) 1576 close(outfd); 1577 if (errfd != 2) 1578 close(errfd); 1579 1580 notify(fork_notifier, 0); 1581 close(pipefd[0]); 1582 /* this close unblocks the read() call above in the parent */ 1583 close(pipefd[1]); 1584 1585 return 0; 1586 } 1587 1588 /* 1589 * device_script - run a program to talk to the specified fds 1590 * (e.g. to run the connector or disconnector script). 1591 * stderr gets connected to the log fd or to the _PATH_CONNERRS file. 1592 */ 1593 int 1594 device_script(program, in, out, dont_wait) 1595 char *program; 1596 int in, out; 1597 int dont_wait; 1598 { 1599 int pid; 1600 int status = -1; 1601 int errfd; 1602 1603 if (log_to_fd >= 0) 1604 errfd = log_to_fd; 1605 else 1606 errfd = open(_PATH_CONNERRS, O_WRONLY | O_APPEND | O_CREAT, 0600); 1607 1608 ++conn_running; 1609 pid = safe_fork(in, out, errfd); 1610 1611 if (pid != 0 && log_to_fd < 0) 1612 close(errfd); 1613 1614 if (pid < 0) { 1615 --conn_running; 1616 error("Failed to create child process: %m"); 1617 return -1; 1618 } 1619 1620 if (pid != 0) { 1621 if (dont_wait) { 1622 record_child(pid, program, NULL, NULL); 1623 status = 0; 1624 } else { 1625 while (waitpid(pid, &status, 0) < 0) { 1626 if (errno == EINTR) 1627 continue; 1628 fatal("error waiting for (dis)connection process: %m"); 1629 } 1630 --conn_running; 1631 } 1632 return (status == 0 ? 0 : -1); 1633 } 1634 1635 /* here we are executing in the child */ 1636 1637 setgid(getgid()); 1638 setuid(uid); 1639 if (getuid() != uid) { 1640 fprintf(stderr, "pppd: setuid failed\n"); 1641 exit(1); 1642 } 1643 execl("/system/bin/sh", "sh", "-c", program, NULL); 1644 perror("pppd: could not exec /bin/sh"); 1645 exit(99); 1646 /* NOTREACHED */ 1647 } 1648 1649 1650 /* 1651 * run-program - execute a program with given arguments, 1652 * but don't wait for it. 1653 * If the program can't be executed, logs an error unless 1654 * must_exist is 0 and the program file doesn't exist. 1655 * Returns -1 if it couldn't fork, 0 if the file doesn't exist 1656 * or isn't an executable plain file, or the process ID of the child. 1657 * If done != NULL, (*done)(arg) will be called later (within 1658 * reap_kids) iff the return value is > 0. 1659 */ 1660 pid_t 1661 run_program(prog, args, must_exist, done, arg) 1662 char *prog; 1663 char **args; 1664 int must_exist; 1665 void (*done) __P((void *)); 1666 void *arg; 1667 { 1668 int pid; 1669 struct stat sbuf; 1670 1671 #ifdef ANDROID_CHANGES 1672 /* Originally linkname is used to create named pid files, which is 1673 * meaningless to android. Here we use it as a suffix of program names, 1674 * so different users can run their own program by specifying it. For 1675 * example, "/etc/ppp/ip-up-vpn" will be executed when IPCP is up and 1676 * linkname is "vpn". Note that "/" is not allowed for security reasons. */ 1677 char file[MAXPATHLEN]; 1678 1679 if (linkname[0] && !strchr(linkname, '/')) { 1680 snprintf(file, MAXPATHLEN, "%s-%s", prog, linkname); 1681 file[MAXPATHLEN - 1] = '\0'; 1682 prog = file; 1683 } 1684 #endif 1685 1686 /* 1687 * First check if the file exists and is executable. 1688 * We don't use access() because that would use the 1689 * real user-id, which might not be root, and the script 1690 * might be accessible only to root. 1691 */ 1692 errno = EINVAL; 1693 if (stat(prog, &sbuf) < 0 || !S_ISREG(sbuf.st_mode) 1694 || (sbuf.st_mode & (S_IXUSR|S_IXGRP|S_IXOTH)) == 0) { 1695 if (must_exist || errno != ENOENT) 1696 warn("Can't execute %s: %m", prog); 1697 return 0; 1698 } 1699 1700 pid = safe_fork(fd_devnull, fd_devnull, fd_devnull); 1701 if (pid == -1) { 1702 error("Failed to create child process for %s: %m", prog); 1703 return -1; 1704 } 1705 if (pid != 0) { 1706 if (debug) 1707 dbglog("Script %s started (pid %d)", prog, pid); 1708 record_child(pid, prog, done, arg); 1709 return pid; 1710 } 1711 1712 /* Leave the current location */ 1713 (void) setsid(); /* No controlling tty. */ 1714 (void) umask (S_IRWXG|S_IRWXO); 1715 (void) chdir ("/"); /* no current directory. */ 1716 setuid(0); /* set real UID = root */ 1717 setgid(getegid()); 1718 1719 #ifdef BSD 1720 /* Force the priority back to zero if pppd is running higher. */ 1721 if (setpriority (PRIO_PROCESS, 0, 0) < 0) 1722 warn("can't reset priority to 0: %m"); 1723 #endif 1724 1725 /* run the program */ 1726 execve(prog, args, script_env); 1727 if (must_exist || errno != ENOENT) { 1728 #ifndef ANDROID_CHANGES 1729 /* have to reopen the log, there's nowhere else 1730 for the message to go. */ 1731 reopen_log(); 1732 syslog(LOG_ERR, "Can't execute %s: %m", prog); 1733 closelog(); 1734 #else 1735 error("Can't execute %s: %m", prog); 1736 #endif 1737 } 1738 _exit(-1); 1739 } 1740 1741 1742 /* 1743 * record_child - add a child process to the list for reap_kids 1744 * to use. 1745 */ 1746 void 1747 record_child(pid, prog, done, arg) 1748 int pid; 1749 char *prog; 1750 void (*done) __P((void *)); 1751 void *arg; 1752 { 1753 struct subprocess *chp; 1754 1755 ++n_children; 1756 1757 chp = (struct subprocess *) malloc(sizeof(struct subprocess)); 1758 if (chp == NULL) { 1759 warn("losing track of %s process", prog); 1760 } else { 1761 chp->pid = pid; 1762 chp->prog = prog; 1763 chp->done = done; 1764 chp->arg = arg; 1765 chp->next = children; 1766 children = chp; 1767 } 1768 } 1769 1770 /* 1771 * childwait_end - we got fed up waiting for the child processes to 1772 * exit, send them all a SIGTERM. 1773 */ 1774 static void 1775 childwait_end(arg) 1776 void *arg; 1777 { 1778 struct subprocess *chp; 1779 1780 for (chp = children; chp != NULL; chp = chp->next) { 1781 if (debug) 1782 dbglog("sending SIGTERM to process %d", chp->pid); 1783 kill(chp->pid, SIGTERM); 1784 } 1785 childwait_done = 1; 1786 } 1787 1788 /* 1789 * reap_kids - get status from any dead child processes, 1790 * and log a message for abnormal terminations. 1791 */ 1792 static int 1793 reap_kids() 1794 { 1795 int pid, status; 1796 struct subprocess *chp, **prevp; 1797 1798 if (n_children == 0) 1799 return 0; 1800 while ((pid = waitpid(-1, &status, WNOHANG)) != -1 && pid != 0) { 1801 for (prevp = &children; (chp = *prevp) != NULL; prevp = &chp->next) { 1802 if (chp->pid == pid) { 1803 --n_children; 1804 *prevp = chp->next; 1805 break; 1806 } 1807 } 1808 if (WIFSIGNALED(status)) { 1809 warn("Child process %s (pid %d) terminated with signal %d", 1810 (chp? chp->prog: "??"), pid, WTERMSIG(status)); 1811 } else if (debug) 1812 dbglog("Script %s finished (pid %d), status = 0x%x", 1813 (chp? chp->prog: "??"), pid, 1814 WIFEXITED(status) ? WEXITSTATUS(status) : status); 1815 if (chp && chp->done) 1816 (*chp->done)(chp->arg); 1817 if (chp) 1818 free(chp); 1819 } 1820 if (pid == -1) { 1821 if (errno == ECHILD) 1822 return -1; 1823 if (errno != EINTR) 1824 error("Error waiting for child process: %m"); 1825 } 1826 return 0; 1827 } 1828 1829 /* 1830 * add_notifier - add a new function to be called when something happens. 1831 */ 1832 void 1833 add_notifier(notif, func, arg) 1834 struct notifier **notif; 1835 notify_func func; 1836 void *arg; 1837 { 1838 struct notifier *np; 1839 1840 np = malloc(sizeof(struct notifier)); 1841 if (np == 0) 1842 novm("notifier struct"); 1843 np->next = *notif; 1844 np->func = func; 1845 np->arg = arg; 1846 *notif = np; 1847 } 1848 1849 /* 1850 * remove_notifier - remove a function from the list of things to 1851 * be called when something happens. 1852 */ 1853 void 1854 remove_notifier(notif, func, arg) 1855 struct notifier **notif; 1856 notify_func func; 1857 void *arg; 1858 { 1859 struct notifier *np; 1860 1861 for (; (np = *notif) != 0; notif = &np->next) { 1862 if (np->func == func && np->arg == arg) { 1863 *notif = np->next; 1864 free(np); 1865 break; 1866 } 1867 } 1868 } 1869 1870 /* 1871 * notify - call a set of functions registered with add_notifier. 1872 */ 1873 void 1874 notify(notif, val) 1875 struct notifier *notif; 1876 int val; 1877 { 1878 struct notifier *np; 1879 1880 while ((np = notif) != 0) { 1881 notif = np->next; 1882 (*np->func)(np->arg, val); 1883 } 1884 } 1885 1886 /* 1887 * novm - log an error message saying we ran out of memory, and die. 1888 */ 1889 void 1890 novm(msg) 1891 char *msg; 1892 { 1893 fatal("Virtual memory exhausted allocating %s\n", msg); 1894 } 1895 1896 /* 1897 * script_setenv - set an environment variable value to be used 1898 * for scripts that we run (e.g. ip-up, auth-up, etc.) 1899 */ 1900 void 1901 script_setenv(var, value, iskey) 1902 char *var, *value; 1903 int iskey; 1904 { 1905 size_t varl = strlen(var); 1906 size_t vl = varl + strlen(value) + 2; 1907 int i; 1908 char *p, *newstring; 1909 1910 newstring = (char *) malloc(vl+1); 1911 if (newstring == 0) 1912 return; 1913 *newstring++ = iskey; 1914 slprintf(newstring, vl, "%s=%s", var, value); 1915 1916 /* check if this variable is already set */ 1917 if (script_env != 0) { 1918 for (i = 0; (p = script_env[i]) != 0; ++i) { 1919 if (strncmp(p, var, varl) == 0 && p[varl] == '=') { 1920 #ifdef USE_TDB 1921 if (p[-1] && pppdb != NULL) 1922 delete_db_key(p); 1923 #endif 1924 free(p-1); 1925 script_env[i] = newstring; 1926 #ifdef USE_TDB 1927 if (iskey && pppdb != NULL) 1928 add_db_key(newstring); 1929 update_db_entry(); 1930 #endif 1931 return; 1932 } 1933 } 1934 } else { 1935 /* no space allocated for script env. ptrs. yet */ 1936 i = 0; 1937 script_env = (char **) malloc(16 * sizeof(char *)); 1938 if (script_env == 0) 1939 return; 1940 s_env_nalloc = 16; 1941 } 1942 1943 /* reallocate script_env with more space if needed */ 1944 if (i + 1 >= s_env_nalloc) { 1945 int new_n = i + 17; 1946 char **newenv = (char **) realloc((void *)script_env, 1947 new_n * sizeof(char *)); 1948 if (newenv == 0) 1949 return; 1950 script_env = newenv; 1951 s_env_nalloc = new_n; 1952 } 1953 1954 script_env[i] = newstring; 1955 script_env[i+1] = 0; 1956 1957 #ifdef USE_TDB 1958 if (pppdb != NULL) { 1959 if (iskey) 1960 add_db_key(newstring); 1961 update_db_entry(); 1962 } 1963 #endif 1964 } 1965 1966 /* 1967 * script_unsetenv - remove a variable from the environment 1968 * for scripts. 1969 */ 1970 void 1971 script_unsetenv(var) 1972 char *var; 1973 { 1974 int vl = strlen(var); 1975 int i; 1976 char *p; 1977 1978 if (script_env == 0) 1979 return; 1980 for (i = 0; (p = script_env[i]) != 0; ++i) { 1981 if (strncmp(p, var, vl) == 0 && p[vl] == '=') { 1982 #ifdef USE_TDB 1983 if (p[-1] && pppdb != NULL) 1984 delete_db_key(p); 1985 #endif 1986 free(p-1); 1987 while ((script_env[i] = script_env[i+1]) != 0) 1988 ++i; 1989 break; 1990 } 1991 } 1992 #ifdef USE_TDB 1993 if (pppdb != NULL) 1994 update_db_entry(); 1995 #endif 1996 } 1997 1998 /* 1999 * Any arbitrary string used as a key for locking the database. 2000 * It doesn't matter what it is as long as all pppds use the same string. 2001 */ 2002 #define PPPD_LOCK_KEY "pppd lock" 2003 2004 /* 2005 * lock_db - get an exclusive lock on the TDB database. 2006 * Used to ensure atomicity of various lookup/modify operations. 2007 */ 2008 void lock_db() 2009 { 2010 #ifdef USE_TDB 2011 TDB_DATA key; 2012 2013 key.dptr = PPPD_LOCK_KEY; 2014 key.dsize = strlen(key.dptr); 2015 tdb_chainlock(pppdb, key); 2016 #endif 2017 } 2018 2019 /* 2020 * unlock_db - remove the exclusive lock obtained by lock_db. 2021 */ 2022 void unlock_db() 2023 { 2024 #ifdef USE_TDB 2025 TDB_DATA key; 2026 2027 key.dptr = PPPD_LOCK_KEY; 2028 key.dsize = strlen(key.dptr); 2029 tdb_chainunlock(pppdb, key); 2030 #endif 2031 } 2032 2033 #ifdef USE_TDB 2034 /* 2035 * update_db_entry - update our entry in the database. 2036 */ 2037 static void 2038 update_db_entry() 2039 { 2040 TDB_DATA key, dbuf; 2041 int vlen, i; 2042 char *p, *q, *vbuf; 2043 2044 if (script_env == NULL) 2045 return; 2046 vlen = 0; 2047 for (i = 0; (p = script_env[i]) != 0; ++i) 2048 vlen += strlen(p) + 1; 2049 vbuf = malloc(vlen + 1); 2050 if (vbuf == 0) 2051 novm("database entry"); 2052 q = vbuf; 2053 for (i = 0; (p = script_env[i]) != 0; ++i) 2054 q += slprintf(q, vbuf + vlen - q, "%s;", p); 2055 2056 key.dptr = db_key; 2057 key.dsize = strlen(db_key); 2058 dbuf.dptr = vbuf; 2059 dbuf.dsize = vlen; 2060 if (tdb_store(pppdb, key, dbuf, TDB_REPLACE)) 2061 error("tdb_store failed: %s", tdb_error(pppdb)); 2062 2063 if (vbuf) 2064 free(vbuf); 2065 2066 } 2067 2068 /* 2069 * add_db_key - add a key that we can use to look up our database entry. 2070 */ 2071 static void 2072 add_db_key(str) 2073 const char *str; 2074 { 2075 TDB_DATA key, dbuf; 2076 2077 key.dptr = (char *) str; 2078 key.dsize = strlen(str); 2079 dbuf.dptr = db_key; 2080 dbuf.dsize = strlen(db_key); 2081 if (tdb_store(pppdb, key, dbuf, TDB_REPLACE)) 2082 error("tdb_store key failed: %s", tdb_error(pppdb)); 2083 } 2084 2085 /* 2086 * delete_db_key - delete a key for looking up our database entry. 2087 */ 2088 static void 2089 delete_db_key(str) 2090 const char *str; 2091 { 2092 TDB_DATA key; 2093 2094 key.dptr = (char *) str; 2095 key.dsize = strlen(str); 2096 tdb_delete(pppdb, key); 2097 } 2098 2099 /* 2100 * cleanup_db - delete all the entries we put in the database. 2101 */ 2102 static void 2103 cleanup_db() 2104 { 2105 TDB_DATA key; 2106 int i; 2107 char *p; 2108 2109 key.dptr = db_key; 2110 key.dsize = strlen(db_key); 2111 tdb_delete(pppdb, key); 2112 for (i = 0; (p = script_env[i]) != 0; ++i) 2113 if (p[-1]) 2114 delete_db_key(p); 2115 } 2116 #endif /* USE_TDB */ 2117
