/* * main.c - Point-to-Point Protocol main module * * Copyright (c) 1989 Carnegie Mellon University. * All rights reserved. * * Redistribution and use in source and binary forms are permitted * provided that the above copyright notice and this paragraph are * duplicated in all such forms and that any documentation, * advertising materials, and other materials related to such * distribution and use acknowledge that the software was developed * by Carnegie Mellon University. The name of the * University may not be used to endorse or promote products derived * from this software without specific prior written permission. * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE. */ #define RCSID "$Id: main.c,v 1.105 2001/03/12 22:58:59 paulus Exp $" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "pppd.h" #include "magic.h" #include "fsm.h" #include "lcp.h" #include "ipcp.h" #ifdef INET6 #include "ipv6cp.h" #endif #include "upap.h" #include "chap.h" #include "ccp.h" #include "pathnames.h" #include "tdb.h" #ifdef CBCP_SUPPORT #include "cbcp.h" #endif #ifdef IPX_CHANGE #include "ipxcp.h" #endif /* IPX_CHANGE */ #ifdef AT_CHANGE #include "atcp.h" #endif static const char rcsid[] = RCSID; /* interface vars */ char ifname[32]; /* Interface name */ int ifunit; /* Interface unit number */ struct channel *the_channel; char *progname; /* Name of this program */ char hostname[MAXNAMELEN]; /* Our hostname */ static char pidfilename[MAXPATHLEN]; /* name of pid file */ static char linkpidfile[MAXPATHLEN]; /* name of linkname pid file */ char ppp_devnam[MAXPATHLEN]; /* name of PPP tty (maybe ttypx) */ uid_t uid; /* Our real user-id */ struct notifier *pidchange = NULL; struct notifier *phasechange = NULL; struct notifier *exitnotify = NULL; struct notifier *sigreceived = NULL; int hungup; /* terminal has been hung up */ int privileged; /* we're running as real uid root */ int need_holdoff; /* need holdoff period before restarting */ int detached; /* have detached from terminal */ volatile int status; /* exit status for pppd */ int unsuccess; /* # unsuccessful connection attempts */ int do_callback; /* != 0 if we should do callback next */ int doing_callback; /* != 0 if we are doing callback */ TDB_CONTEXT *pppdb; /* database for storing status etc. */ char db_key[32]; int (*holdoff_hook) __P((void)) = NULL; int (*new_phase_hook) __P((int)) = NULL; static int conn_running; /* we have a [dis]connector running */ static int devfd; /* fd of underlying device */ static int fd_ppp = -1; /* fd for talking PPP */ static int fd_loop; /* fd for getting demand-dial packets */ int phase; /* where the link is at */ int kill_link; int open_ccp_flag; int listen_time; int got_sigusr2; int got_sigterm; int got_sighup; static int waiting; static sigjmp_buf sigjmp; char **script_env; /* Env. variable values for scripts */ int s_env_nalloc; /* # words avail at script_env */ u_char outpacket_buf[PPP_MRU+PPP_HDRLEN]; /* buffer for outgoing packet */ u_char inpacket_buf[PPP_MRU+PPP_HDRLEN]; /* buffer for incoming packet */ static int n_children; /* # child processes still running */ static int got_sigchld; /* set if we have received a SIGCHLD */ int privopen; /* don't lock, open device as root */ char *no_ppp_msg = "Sorry - this system lacks PPP kernel support\n"; GIDSET_TYPE groups[NGROUPS_MAX];/* groups the user is in */ int ngroups; /* How many groups valid in groups */ static struct timeval start_time; /* Time when link was started. */ struct pppd_stats link_stats; int link_connect_time; int link_stats_valid; /* * We maintain a list of child process pids and * functions to call when they exit. */ struct subprocess { pid_t pid; char *prog; void (*done) __P((void *)); void *arg; struct subprocess *next; }; static struct subprocess *children; /* Prototypes for procedures local to this file. */ static void setup_signals __P((void)); static void create_pidfile __P((void)); static void create_linkpidfile __P((void)); static void cleanup __P((void)); static void get_input __P((void)); static void calltimeout __P((void)); static struct timeval *timeleft __P((struct timeval *)); static void kill_my_pg __P((int)); static void hup __P((int)); static void term __P((int)); static void chld __P((int)); static void toggle_debug __P((int)); static void open_ccp __P((int)); static void bad_signal __P((int)); static void holdoff_end __P((void *)); static int reap_kids __P((int waitfor)); static void update_db_entry __P((void)); static void add_db_key __P((const char *)); static void delete_db_key __P((const char *)); static void cleanup_db __P((void)); static void handle_events __P((void)); extern char *ttyname __P((int)); extern char *getlogin __P((void)); int main __P((int, char *[])); #ifdef ultrix #undef O_NONBLOCK #define O_NONBLOCK O_NDELAY #endif #ifdef ULTRIX #define setlogmask(x) #endif /* * PPP Data Link Layer "protocol" table. * One entry per supported protocol. * The last entry must be NULL. */ struct protent *protocols[] = { &lcp_protent, &pap_protent, &chap_protent, #ifdef CBCP_SUPPORT &cbcp_protent, #endif &ipcp_protent, #ifdef INET6 &ipv6cp_protent, #endif &ccp_protent, #ifdef IPX_CHANGE &ipxcp_protent, #endif #ifdef AT_CHANGE &atcp_protent, #endif NULL }; /* * If PPP_DRV_NAME is not defined, use the default "ppp" as the device name. */ #if !defined(PPP_DRV_NAME) #define PPP_DRV_NAME "ppp" #endif /* !defined(PPP_DRV_NAME) */ int main(argc, argv) int argc; char *argv[]; { int i, t; char *p; struct passwd *pw; struct protent *protp; char numbuf[16]; new_phase(PHASE_INITIALIZE); /* * Ensure that fds 0, 1, 2 are open, to /dev/null if nowhere else. * This way we can close 0, 1, 2 in detach() without clobbering * a fd that we are using. */ if ((i = open("/dev/null", O_RDWR)) >= 0) { while (0 <= i && i <= 2) i = dup(i); if (i >= 0) close(i); } script_env = NULL; /* Initialize syslog facilities */ reopen_log(); if (gethostname(hostname, MAXNAMELEN) < 0 ) { option_error("Couldn't get hostname: %m"); exit(1); } hostname[MAXNAMELEN-1] = 0; /* make sure we don't create world or group writable files. */ umask(umask(0777) | 022); uid = getuid(); privileged = uid == 0; slprintf(numbuf, sizeof(numbuf), "%d", uid); script_setenv("ORIG_UID", numbuf, 0); ngroups = getgroups(NGROUPS_MAX, groups); /* * Initialize magic number generator now so that protocols may * use magic numbers in initialization. */ magic_init(); /* * Initialize each protocol. */ for (i = 0; (protp = protocols[i]) != NULL; ++i) (*protp->init)(0); /* * Initialize the default channel. */ tty_init(); progname = *argv; /* * Parse, in order, the system options file, the user's options file, * and the command line arguments. */ if (!options_from_file(_PATH_SYSOPTIONS, !privileged, 0, 1) || !options_from_user() || !parse_args(argc-1, argv+1)) exit(EXIT_OPTION_ERROR); devnam_fixed = 1; /* can no longer change device name */ /* * Work out the device name, if it hasn't already been specified, * and parse the tty's options file. */ if (the_channel->process_extra_options) (*the_channel->process_extra_options)(); if (debug) setlogmask(LOG_UPTO(LOG_DEBUG)); /* * Check that we are running as root. */ if (geteuid() != 0) { option_error("must be root to run %s, since it is not setuid-root", argv[0]); exit(EXIT_NOT_ROOT); } if (!ppp_available()) { option_error("%s", no_ppp_msg); exit(EXIT_NO_KERNEL_SUPPORT); } /* * Check that the options given are valid and consistent. */ check_options(); if (!sys_check_options()) exit(EXIT_OPTION_ERROR); auth_check_options(); #ifdef HAVE_MULTILINK mp_check_options(); #endif for (i = 0; (protp = protocols[i]) != NULL; ++i) if (protp->check_options != NULL) (*protp->check_options)(); if (the_channel->check_options) (*the_channel->check_options)(); if (dump_options || dryrun) { init_pr_log(NULL, LOG_INFO); print_options(pr_log, NULL); end_pr_log(); if (dryrun) die(0); } /* * Initialize system-dependent stuff. */ sys_init(); pppdb = tdb_open(_PATH_PPPDB, 0, 0, O_RDWR|O_CREAT, 0644); if (pppdb != NULL) { slprintf(db_key, sizeof(db_key), "pppd%d", getpid()); update_db_entry(); } else { warn("Warning: couldn't open ppp database %s", _PATH_PPPDB); if (multilink) { warn("Warning: disabling multilink"); multilink = 0; } } /* * Detach ourselves from the terminal, if required, * and identify who is running us. */ if (!nodetach && !updetach) detach(); p = getlogin(); if (p == NULL) { pw = getpwuid(uid); if (pw != NULL && pw->pw_name != NULL) p = pw->pw_name; else p = "(unknown)"; } syslog(LOG_NOTICE, "pppd %s started by %s, uid %d", VERSION, p, uid); script_setenv("PPPLOGNAME", p, 0); if (devnam[0]) script_setenv("DEVICE", devnam, 1); slprintf(numbuf, sizeof(numbuf), "%d", getpid()); script_setenv("PPPD_PID", numbuf, 1); setup_signals(); waiting = 0; create_linkpidfile(); /* * If we're doing dial-on-demand, set up the interface now. */ if (demand) { /* * Open the loopback channel and set it up to be the ppp interface. */ tdb_writelock(pppdb); fd_loop = open_ppp_loopback(); set_ifunit(1); tdb_writeunlock(pppdb); /* * Configure the interface and mark it up, etc. */ demand_conf(); } do_callback = 0; for (;;) { listen_time = 0; need_holdoff = 1; devfd = -1; status = EXIT_OK; ++unsuccess; doing_callback = do_callback; do_callback = 0; if (demand && !doing_callback) { /* * Don't do anything until we see some activity. */ new_phase(PHASE_DORMANT); demand_unblock(); add_fd(fd_loop); for (;;) { handle_events(); if (kill_link && !persist) break; if (get_loop_output()) break; } remove_fd(fd_loop); if (kill_link && !persist) break; /* * Now we want to bring up the link. */ demand_block(); info("Starting link"); } new_phase(PHASE_SERIALCONN); devfd = the_channel->connect(); if (devfd < 0) goto fail; /* set up the serial device as a ppp interface */ tdb_writelock(pppdb); fd_ppp = the_channel->establish_ppp(devfd); if (fd_ppp < 0) { tdb_writeunlock(pppdb); status = EXIT_FATAL_ERROR; goto disconnect; } if (!demand && ifunit >= 0) set_ifunit(1); tdb_writeunlock(pppdb); /* * Start opening the connection and wait for * incoming events (reply, timeout, etc.). */ notice("Connect: %s <--> %s", ifname, ppp_devnam); gettimeofday(&start_time, NULL); link_stats_valid = 0; script_unsetenv("CONNECT_TIME"); script_unsetenv("BYTES_SENT"); script_unsetenv("BYTES_RCVD"); lcp_lowerup(0); add_fd(fd_ppp); lcp_open(0); /* Start protocol */ status = EXIT_NEGOTIATION_FAILED; new_phase(PHASE_ESTABLISH); while (phase != PHASE_DEAD) { handle_events(); get_input(); if (kill_link) lcp_close(0, "User request"); if (open_ccp_flag) { if (phase == PHASE_NETWORK || phase == PHASE_RUNNING) { ccp_fsm[0].flags = OPT_RESTART; /* clears OPT_SILENT */ (*ccp_protent.open)(0); } } } /* * Print connect time and statistics. */ if (link_stats_valid) { int t = (link_connect_time + 5) / 6; /* 1/10ths of minutes */ info("Connect time %d.%d minutes.", t/10, t%10); info("Sent %u bytes, received %u bytes.", link_stats.bytes_out, link_stats.bytes_in); } /* * Delete pid file before disestablishing ppp. Otherwise it * can happen that another pppd gets the same unit and then * we delete its pid file. */ if (!demand) { if (pidfilename[0] != 0 && unlink(pidfilename) < 0 && errno != ENOENT) warn("unable to delete pid file %s: %m", pidfilename); pidfilename[0] = 0; } /* * If we may want to bring the link up again, transfer * the ppp unit back to the loopback. Set the * real serial device back to its normal mode of operation. */ remove_fd(fd_ppp); clean_check(); the_channel->disestablish_ppp(devfd); fd_ppp = -1; if (!hungup) lcp_lowerdown(0); if (!demand) script_unsetenv("IFNAME"); /* * Run disconnector script, if requested. * XXX we may not be able to do this if the line has hung up! */ disconnect: new_phase(PHASE_DISCONNECT); the_channel->disconnect(); fail: if (the_channel->cleanup) (*the_channel->cleanup)(); if (!demand) { if (pidfilename[0] != 0 && unlink(pidfilename) < 0 && errno != ENOENT) warn("unable to delete pid file %s: %m", pidfilename); pidfilename[0] = 0; } if (!persist || (maxfail > 0 && unsuccess >= maxfail)) break; if (demand) demand_discard(); t = need_holdoff? holdoff: 0; if (holdoff_hook) t = (*holdoff_hook)(); if (t > 0) { new_phase(PHASE_HOLDOFF); TIMEOUT(holdoff_end, NULL, t); do { handle_events(); if (kill_link) new_phase(PHASE_DORMANT); /* allow signal to end holdoff */ } while (phase == PHASE_HOLDOFF); if (!persist) break; } } /* Wait for scripts to finish */ /* XXX should have a timeout here */ while (n_children > 0) { if (debug) { struct subprocess *chp; dbglog("Waiting for %d child processes...", n_children); for (chp = children; chp != NULL; chp = chp->next) dbglog(" script %s, pid %d", chp->prog, chp->pid); } if (reap_kids(1) < 0) break; } die(status); return 0; } /* * handle_events - wait for something to happen and respond to it. */ static void handle_events() { struct timeval timo; sigset_t mask; kill_link = open_ccp_flag = 0; if (sigsetjmp(sigjmp, 1) == 0) { sigprocmask(SIG_BLOCK, &mask, NULL); if (got_sighup || got_sigterm || got_sigusr2 || got_sigchld) { sigprocmask(SIG_UNBLOCK, &mask, NULL); } else { waiting = 1; sigprocmask(SIG_UNBLOCK, &mask, NULL); wait_input(timeleft(&timo)); } } waiting = 0; calltimeout(); if (got_sighup) { kill_link = 1; got_sighup = 0; if (status != EXIT_HANGUP) status = EXIT_USER_REQUEST; } if (got_sigterm) { kill_link = 1; persist = 0; status = EXIT_USER_REQUEST; got_sigterm = 0; } if (got_sigchld) { reap_kids(0); /* Don't leave dead kids lying around */ got_sigchld = 0; } if (got_sigusr2) { open_ccp_flag = 1; got_sigusr2 = 0; } } /* * setup_signals - initialize signal handling. */ static void setup_signals() { struct sigaction sa; sigset_t mask; /* * Compute mask of all interesting signals and install signal handlers * for each. Only one signal handler may be active at a time. Therefore, * all other signals should be masked when any handler is executing. */ sigemptyset(&mask); sigaddset(&mask, SIGHUP); sigaddset(&mask, SIGINT); sigaddset(&mask, SIGTERM); sigaddset(&mask, SIGCHLD); sigaddset(&mask, SIGUSR2); #define SIGNAL(s, handler) do { \ sa.sa_handler = handler; \ if (sigaction(s, &sa, NULL) < 0) \ fatal("Couldn't establish signal handler (%d): %m", s); \ } while (0) sa.sa_mask = mask; sa.sa_flags = 0; SIGNAL(SIGHUP, hup); /* Hangup */ SIGNAL(SIGINT, term); /* Interrupt */ SIGNAL(SIGTERM, term); /* Terminate */ SIGNAL(SIGCHLD, chld); SIGNAL(SIGUSR1, toggle_debug); /* Toggle debug flag */ SIGNAL(SIGUSR2, open_ccp); /* Reopen CCP */ /* * Install a handler for other signals which would otherwise * cause pppd to exit without cleaning up. */ SIGNAL(SIGABRT, bad_signal); SIGNAL(SIGALRM, bad_signal); SIGNAL(SIGFPE, bad_signal); SIGNAL(SIGILL, bad_signal); SIGNAL(SIGPIPE, bad_signal); SIGNAL(SIGQUIT, bad_signal); SIGNAL(SIGSEGV, bad_signal); #ifdef SIGBUS SIGNAL(SIGBUS, bad_signal); #endif #ifdef SIGEMT SIGNAL(SIGEMT, bad_signal); #endif #ifdef SIGPOLL SIGNAL(SIGPOLL, bad_signal); #endif #ifdef SIGPROF SIGNAL(SIGPROF, bad_signal); #endif #ifdef SIGSYS SIGNAL(SIGSYS, bad_signal); #endif #ifdef SIGTRAP SIGNAL(SIGTRAP, bad_signal); #endif #ifdef SIGVTALRM SIGNAL(SIGVTALRM, bad_signal); #endif #ifdef SIGXCPU SIGNAL(SIGXCPU, bad_signal); #endif #ifdef SIGXFSZ SIGNAL(SIGXFSZ, bad_signal); #endif /* * Apparently we can get a SIGPIPE when we call syslog, if * syslogd has died and been restarted. Ignoring it seems * be sufficient. */ signal(SIGPIPE, SIG_IGN); } /* * set_ifunit - do things we need to do once we know which ppp * unit we are using. */ void set_ifunit(iskey) int iskey; { info("Using interface %s%d", PPP_DRV_NAME, ifunit); slprintf(ifname, sizeof(ifname), "%s%d", PPP_DRV_NAME, ifunit); script_setenv("IFNAME", ifname, iskey); if (iskey) { create_pidfile(); /* write pid to file */ create_linkpidfile(); } } /* * detach - detach us from the controlling terminal. */ void detach() { int pid; char numbuf[16]; if (detached) return; if ((pid = fork()) < 0) { error("Couldn't detach (fork failed: %m)"); die(1); /* or just return? */ } if (pid != 0) { /* parent */ notify(pidchange, pid); exit(0); /* parent dies */ } setsid(); chdir("/"); close(0); close(1); close(2); detached = 1; if (log_default) log_to_fd = -1; /* update pid files if they have been written already */ if (pidfilename[0]) create_pidfile(); if (linkpidfile[0]) create_linkpidfile(); slprintf(numbuf, sizeof(numbuf), "%d", getpid()); script_setenv("PPPD_PID", numbuf, 1); } /* * reopen_log - (re)open our connection to syslog. */ void reopen_log() { #ifdef ULTRIX openlog("pppd", LOG_PID); #else openlog("pppd", LOG_PID | LOG_NDELAY, LOG_PPP); setlogmask(LOG_UPTO(LOG_INFO)); #endif } /* * Create a file containing our process ID. */ static void create_pidfile() { FILE *pidfile; slprintf(pidfilename, sizeof(pidfilename), "%s%s.pid", _PATH_VARRUN, ifname); if ((pidfile = fopen(pidfilename, "w")) != NULL) { fprintf(pidfile, "%d\n", getpid()); (void) fclose(pidfile); } else { error("Failed to create pid file %s: %m", pidfilename); pidfilename[0] = 0; } } static void create_linkpidfile() { FILE *pidfile; if (linkname[0] == 0) return; script_setenv("LINKNAME", linkname, 1); slprintf(linkpidfile, sizeof(linkpidfile), "%sppp-%s.pid", _PATH_VARRUN, linkname); if ((pidfile = fopen(linkpidfile, "w")) != NULL) { fprintf(pidfile, "%d\n", getpid()); if (ifname[0]) fprintf(pidfile, "%s\n", ifname); (void) fclose(pidfile); } else { error("Failed to create pid file %s: %m", linkpidfile); linkpidfile[0] = 0; } } /* * holdoff_end - called via a timeout when the holdoff period ends. */ static void holdoff_end(arg) void *arg; { new_phase(PHASE_DORMANT); } /* List of protocol names, to make our messages a little more informative. */ struct protocol_list { u_short proto; const char *name; } protocol_list[] = { { 0x21, "IP" }, { 0x23, "OSI Network Layer" }, { 0x25, "Xerox NS IDP" }, { 0x27, "DECnet Phase IV" }, { 0x29, "Appletalk" }, { 0x2b, "Novell IPX" }, { 0x2d, "VJ compressed TCP/IP" }, { 0x2f, "VJ uncompressed TCP/IP" }, { 0x31, "Bridging PDU" }, { 0x33, "Stream Protocol ST-II" }, { 0x35, "Banyan Vines" }, { 0x39, "AppleTalk EDDP" }, { 0x3b, "AppleTalk SmartBuffered" }, { 0x3d, "Multi-Link" }, { 0x3f, "NETBIOS Framing" }, { 0x41, "Cisco Systems" }, { 0x43, "Ascom Timeplex" }, { 0x45, "Fujitsu Link Backup and Load Balancing (LBLB)" }, { 0x47, "DCA Remote Lan" }, { 0x49, "Serial Data Transport Protocol (PPP-SDTP)" }, { 0x4b, "SNA over 802.2" }, { 0x4d, "SNA" }, { 0x4f, "IP6 Header Compression" }, { 0x6f, "Stampede Bridging" }, { 0xfb, "single-link compression" }, { 0xfd, "1st choice compression" }, { 0x0201, "802.1d Hello Packets" }, { 0x0203, "IBM Source Routing BPDU" }, { 0x0205, "DEC LANBridge100 Spanning Tree" }, { 0x0231, "Luxcom" }, { 0x0233, "Sigma Network Systems" }, { 0x8021, "Internet Protocol Control Protocol" }, { 0x8023, "OSI Network Layer Control Protocol" }, { 0x8025, "Xerox NS IDP Control Protocol" }, { 0x8027, "DECnet Phase IV Control Protocol" }, { 0x8029, "Appletalk Control Protocol" }, { 0x802b, "Novell IPX Control Protocol" }, { 0x8031, "Bridging NCP" }, { 0x8033, "Stream Protocol Control Protocol" }, { 0x8035, "Banyan Vines Control Protocol" }, { 0x803d, "Multi-Link Control Protocol" }, { 0x803f, "NETBIOS Framing Control Protocol" }, { 0x8041, "Cisco Systems Control Protocol" }, { 0x8043, "Ascom Timeplex" }, { 0x8045, "Fujitsu LBLB Control Protocol" }, { 0x8047, "DCA Remote Lan Network Control Protocol (RLNCP)" }, { 0x8049, "Serial Data Control Protocol (PPP-SDCP)" }, { 0x804b, "SNA over 802.2 Control Protocol" }, { 0x804d, "SNA Control Protocol" }, { 0x804f, "IP6 Header Compression Control Protocol" }, { 0x006f, "Stampede Bridging Control Protocol" }, { 0x80fb, "Single Link Compression Control Protocol" }, { 0x80fd, "Compression Control Protocol" }, { 0xc021, "Link Control Protocol" }, { 0xc023, "Password Authentication Protocol" }, { 0xc025, "Link Quality Report" }, { 0xc027, "Shiva Password Authentication Protocol" }, { 0xc029, "CallBack Control Protocol (CBCP)" }, { 0xc081, "Container Control Protocol" }, { 0xc223, "Challenge Handshake Authentication Protocol" }, { 0xc281, "Proprietary Authentication Protocol" }, { 0, NULL }, }; /* * protocol_name - find a name for a PPP protocol. */ const char * protocol_name(proto) int proto; { struct protocol_list *lp; for (lp = protocol_list; lp->proto != 0; ++lp) if (proto == lp->proto) return lp->name; return NULL; } /* * get_input - called when incoming data is available. */ static void get_input() { int len, i; u_char *p; u_short protocol; struct protent *protp; p = inpacket_buf; /* point to beginning of packet buffer */ len = read_packet(inpacket_buf); if (len < 0) return; if (len == 0) { notice("Modem hangup"); hungup = 1; status = EXIT_HANGUP; lcp_lowerdown(0); /* serial link is no longer available */ link_terminated(0); return; } if (debug /*&& (debugflags & DBG_INPACKET)*/) dbglog("rcvd %P", p, len); if (len < PPP_HDRLEN) { MAINDEBUG(("io(): Received short packet.")); return; } p += 2; /* Skip address and control */ GETSHORT(protocol, p); len -= PPP_HDRLEN; /* * Toss all non-LCP packets unless LCP is OPEN. */ if (protocol != PPP_LCP && lcp_fsm[0].state != OPENED) { MAINDEBUG(("get_input: Received non-LCP packet when LCP not open.")); return; } /* * Until we get past the authentication phase, toss all packets * except LCP, LQR and authentication packets. */ if (phase <= PHASE_AUTHENTICATE && !(protocol == PPP_LCP || protocol == PPP_LQR || protocol == PPP_PAP || protocol == PPP_CHAP)) { MAINDEBUG(("get_input: discarding proto 0x%x in phase %d", protocol, phase)); return; } /* * Upcall the proper protocol input routine. */ for (i = 0; (protp = protocols[i]) != NULL; ++i) { if (protp->protocol == protocol && protp->enabled_flag) { (*protp->input)(0, p, len); return; } if (protocol == (protp->protocol & ~0x8000) && protp->enabled_flag && protp->datainput != NULL) { (*protp->datainput)(0, p, len); return; } } if (debug) { const char *pname = protocol_name(protocol); if (pname != NULL) warn("Unsupported protocol '%s' (0x%x) received", pname, protocol); else warn("Unsupported protocol 0x%x received", protocol); } lcp_sprotrej(0, p - PPP_HDRLEN, len + PPP_HDRLEN); } /* * new_phase - signal the start of a new phase of pppd's operation. */ void new_phase(p) int p; { phase = p; if (new_phase_hook) (*new_phase_hook)(p); notify(phasechange, p); } /* * die - clean up state and exit with the specified status. */ void die(status) int status; { cleanup(); notify(exitnotify, status); syslog(LOG_INFO, "Exit."); exit(status); } /* * cleanup - restore anything which needs to be restored before we exit */ /* ARGSUSED */ static void cleanup() { sys_cleanup(); if (fd_ppp >= 0) the_channel->disestablish_ppp(devfd); if (the_channel->cleanup) (*the_channel->cleanup)(); if (pidfilename[0] != 0 && unlink(pidfilename) < 0 && errno != ENOENT) warn("unable to delete pid file %s: %m", pidfilename); pidfilename[0] = 0; if (linkpidfile[0] != 0 && unlink(linkpidfile) < 0 && errno != ENOENT) warn("unable to delete pid file %s: %m", linkpidfile); linkpidfile[0] = 0; if (pppdb != NULL) cleanup_db(); } /* * update_link_stats - get stats at link termination. */ void update_link_stats(u) int u; { struct timeval now; char numbuf[32]; if (!get_ppp_stats(u, &link_stats) || gettimeofday(&now, NULL) < 0) return; link_connect_time = now.tv_sec - start_time.tv_sec; link_stats_valid = 1; slprintf(numbuf, sizeof(numbuf), "%d", link_connect_time); script_setenv("CONNECT_TIME", numbuf, 0); slprintf(numbuf, sizeof(numbuf), "%d", link_stats.bytes_out); script_setenv("BYTES_SENT", numbuf, 0); slprintf(numbuf, sizeof(numbuf), "%d", link_stats.bytes_in); script_setenv("BYTES_RCVD", numbuf, 0); } struct callout { struct timeval c_time; /* time at which to call routine */ void *c_arg; /* argument to routine */ void (*c_func) __P((void *)); /* routine */ struct callout *c_next; }; static struct callout *callout = NULL; /* Callout list */ static struct timeval timenow; /* Current time */ /* * timeout - Schedule a timeout. * * Note that this timeout takes the number of milliseconds, NOT hz (as in * the kernel). */ void timeout(func, arg, secs, usecs) void (*func) __P((void *)); void *arg; int secs, usecs; { struct callout *newp, *p, **pp; MAINDEBUG(("Timeout %p:%p in %d.%03d seconds.", func, arg, time / 1000, time % 1000)); /* * Allocate timeout. */ if ((newp = (struct callout *) malloc(sizeof(struct callout))) == NULL) fatal("Out of memory in timeout()!"); newp->c_arg = arg; newp->c_func = func; gettimeofday(&timenow, NULL); newp->c_time.tv_sec = timenow.tv_sec + secs; newp->c_time.tv_usec = timenow.tv_usec + usecs; if (newp->c_time.tv_usec >= 1000000) { newp->c_time.tv_sec += newp->c_time.tv_usec / 1000000; newp->c_time.tv_usec %= 1000000; } /* * Find correct place and link it in. */ for (pp = &callout; (p = *pp); pp = &p->c_next) if (newp->c_time.tv_sec < p->c_time.tv_sec || (newp->c_time.tv_sec == p->c_time.tv_sec && newp->c_time.tv_usec < p->c_time.tv_usec)) break; newp->c_next = p; *pp = newp; } /* * untimeout - Unschedule a timeout. */ void untimeout(func, arg) void (*func) __P((void *)); void *arg; { struct callout **copp, *freep; MAINDEBUG(("Untimeout %p:%p.", func, arg)); /* * Find first matching timeout and remove it from the list. */ for (copp = &callout; (freep = *copp); copp = &freep->c_next) if (freep->c_func == func && freep->c_arg == arg) { *copp = freep->c_next; free((char *) freep); break; } } /* * calltimeout - Call any timeout routines which are now due. */ static void calltimeout() { struct callout *p; while (callout != NULL) { p = callout; if (gettimeofday(&timenow, NULL) < 0) fatal("Failed to get time of day: %m"); if (!(p->c_time.tv_sec < timenow.tv_sec || (p->c_time.tv_sec == timenow.tv_sec && p->c_time.tv_usec <= timenow.tv_usec))) break; /* no, it's not time yet */ callout = p->c_next; (*p->c_func)(p->c_arg); free((char *) p); } } /* * timeleft - return the length of time until the next timeout is due. */ static struct timeval * timeleft(tvp) struct timeval *tvp; { if (callout == NULL) return NULL; gettimeofday(&timenow, NULL); tvp->tv_sec = callout->c_time.tv_sec - timenow.tv_sec; tvp->tv_usec = callout->c_time.tv_usec - timenow.tv_usec; if (tvp->tv_usec < 0) { tvp->tv_usec += 1000000; tvp->tv_sec -= 1; } if (tvp->tv_sec < 0) tvp->tv_sec = tvp->tv_usec = 0; return tvp; } /* * kill_my_pg - send a signal to our process group, and ignore it ourselves. */ static void kill_my_pg(sig) int sig; { struct sigaction act, oldact; act.sa_handler = SIG_IGN; act.sa_flags = 0; kill(0, sig); sigaction(sig, &act, &oldact); sigaction(sig, &oldact, NULL); } /* * hup - Catch SIGHUP signal. * * Indicates that the physical layer has been disconnected. * We don't rely on this indication; if the user has sent this * signal, we just take the link down. */ static void hup(sig) int sig; { info("Hangup (SIGHUP)"); got_sighup = 1; if (conn_running) /* Send the signal to the [dis]connector process(es) also */ kill_my_pg(sig); notify(sigreceived, sig); if (waiting) siglongjmp(sigjmp, 1); } /* * term - Catch SIGTERM signal and SIGINT signal (^C/del). * * Indicates that we should initiate a graceful disconnect and exit. */ /*ARGSUSED*/ static void term(sig) int sig; { info("Terminating on signal %d.", sig); got_sigterm = 1; if (conn_running) /* Send the signal to the [dis]connector process(es) also */ kill_my_pg(sig); notify(sigreceived, sig); if (waiting) siglongjmp(sigjmp, 1); } /* * chld - Catch SIGCHLD signal. * Sets a flag so we will call reap_kids in the mainline. */ static void chld(sig) int sig; { got_sigchld = 1; if (waiting) siglongjmp(sigjmp, 1); } /* * toggle_debug - Catch SIGUSR1 signal. * * Toggle debug flag. */ /*ARGSUSED*/ static void toggle_debug(sig) int sig; { debug = !debug; if (debug) { setlogmask(LOG_UPTO(LOG_DEBUG)); } else { setlogmask(LOG_UPTO(LOG_WARNING)); } } /* * open_ccp - Catch SIGUSR2 signal. * * Try to (re)negotiate compression. */ /*ARGSUSED*/ static void open_ccp(sig) int sig; { got_sigusr2 = 1; if (waiting) siglongjmp(sigjmp, 1); } /* * bad_signal - We've caught a fatal signal. Clean up state and exit. */ static void bad_signal(sig) int sig; { static int crashed = 0; if (crashed) _exit(127); crashed = 1; error("Fatal signal %d", sig); if (conn_running) kill_my_pg(SIGTERM); notify(sigreceived, sig); die(127); } /* * device_script - run a program to talk to the specified fds * (e.g. to run the connector or disconnector script). * stderr gets connected to the log fd or to the _PATH_CONNERRS file. */ int device_script(program, in, out, dont_wait) char *program; int in, out; int dont_wait; { int pid, fd; int status = -1; int errfd; ++conn_running; pid = fork(); if (pid < 0) { --conn_running; error("Failed to create child process: %m"); return -1; } if (pid != 0) { if (dont_wait) { record_child(pid, program, NULL, NULL); status = 0; } else { while (waitpid(pid, &status, 0) < 0) { if (errno == EINTR) continue; fatal("error waiting for (dis)connection process: %m"); } --conn_running; } return (status == 0 ? 0 : -1); } /* here we are executing in the child */ /* make sure fds 0, 1, 2 are occupied */ while ((fd = dup(in)) >= 0) { if (fd > 2) { close(fd); break; } } /* dup in and out to fds > 2 */ in = dup(in); out = dup(out); if (log_to_fd >= 0) { errfd = dup(log_to_fd); } else { errfd = open(_PATH_CONNERRS, O_WRONLY | O_APPEND | O_CREAT, 0600); } /* close fds 0 - 2 and any others we can think of */ close(0); close(1); close(2); sys_close(); if (the_channel->close) (*the_channel->close)(); closelog(); /* dup the in, out, err fds to 0, 1, 2 */ dup2(in, 0); close(in); dup2(out, 1); close(out); if (errfd >= 0) { dup2(errfd, 2); close(errfd); } setuid(uid); if (getuid() != uid) { error("setuid failed"); exit(1); } setgid(getgid()); execl("/bin/sh", "sh", "-c", program, (char *)0); error("could not exec /bin/sh: %m"); exit(99); /* NOTREACHED */ } /* * run-program - execute a program with given arguments, * but don't wait for it. * If the program can't be executed, logs an error unless * must_exist is 0 and the program file doesn't exist. * Returns -1 if it couldn't fork, 0 if the file doesn't exist * or isn't an executable plain file, or the process ID of the child. * If done != NULL, (*done)(arg) will be called later (within * reap_kids) iff the return value is > 0. */ pid_t run_program(prog, args, must_exist, done, arg) char *prog; char **args; int must_exist; void (*done) __P((void *)); void *arg; { int pid; struct stat sbuf; /* * First check if the file exists and is executable. * We don't use access() because that would use the * real user-id, which might not be root, and the script * might be accessible only to root. */ errno = EINVAL; if (stat(prog, &sbuf) < 0 || !S_ISREG(sbuf.st_mode) || (sbuf.st_mode & (S_IXUSR|S_IXGRP|S_IXOTH)) == 0) { if (must_exist || errno != ENOENT) warn("Can't execute %s: %m", prog); return 0; } pid = fork(); if (pid == -1) { error("Failed to create child process for %s: %m", prog); return -1; } if (pid == 0) { int new_fd; /* Leave the current location */ (void) setsid(); /* No controlling tty. */ (void) umask (S_IRWXG|S_IRWXO); (void) chdir ("/"); /* no current directory. */ setuid(0); /* set real UID = root */ setgid(getegid()); /* Ensure that nothing of our device environment is inherited. */ sys_close(); closelog(); close (0); close (1); close (2); if (the_channel->close) (*the_channel->close)(); /* Don't pass handles to the PPP device, even by accident. */ new_fd = open (_PATH_DEVNULL, O_RDWR); if (new_fd >= 0) { if (new_fd != 0) { dup2 (new_fd, 0); /* stdin <- /dev/null */ close (new_fd); } dup2 (0, 1); /* stdout -> /dev/null */ dup2 (0, 2); /* stderr -> /dev/null */ } #ifdef BSD /* Force the priority back to zero if pppd is running higher. */ if (setpriority (PRIO_PROCESS, 0, 0) < 0) warn("can't reset priority to 0: %m"); #endif /* SysV recommends a second fork at this point. */ /* run the program */ execve(prog, args, script_env); if (must_exist || errno != ENOENT) { /* have to reopen the log, there's nowhere else for the message to go. */ reopen_log(); syslog(LOG_ERR, "Can't execute %s: %m", prog); closelog(); } _exit(-1); } if (debug) dbglog("Script %s started (pid %d)", prog, pid); record_child(pid, prog, done, arg); return pid; } /* * record_child - add a child process to the list for reap_kids * to use. */ void record_child(pid, prog, done, arg) int pid; char *prog; void (*done) __P((void *)); void *arg; { struct subprocess *chp; ++n_children; chp = (struct subprocess *) malloc(sizeof(struct subprocess)); if (chp == NULL) { warn("losing track of %s process", prog); } else { chp->pid = pid; chp->prog = prog; chp->done = done; chp->arg = arg; chp->next = children; children = chp; } } /* * reap_kids - get status from any dead child processes, * and log a message for abnormal terminations. */ static int reap_kids(waitfor) int waitfor; { int pid, status; struct subprocess *chp, **prevp; if (n_children == 0) return 0; while ((pid = waitpid(-1, &status, (waitfor? 0: WNOHANG))) != -1 && pid != 0) { for (prevp = &children; (chp = *prevp) != NULL; prevp = &chp->next) { if (chp->pid == pid) { --n_children; *prevp = chp->next; break; } } if (WIFSIGNALED(status)) { warn("Child process %s (pid %d) terminated with signal %d", (chp? chp->prog: "??"), pid, WTERMSIG(status)); } else if (debug) dbglog("Script %s finished (pid %d), status = 0x%x", (chp? chp->prog: "??"), pid, status); if (chp && chp->done) (*chp->done)(chp->arg); if (chp) free(chp); } if (pid == -1) { if (errno == ECHILD) return -1; if (errno != EINTR) error("Error waiting for child process: %m"); } return 0; } /* * add_notifier - add a new function to be called when something happens. */ void add_notifier(notif, func, arg) struct notifier **notif; notify_func func; void *arg; { struct notifier *np; np = malloc(sizeof(struct notifier)); if (np == 0) novm("notifier struct"); np->next = *notif; np->func = func; np->arg = arg; *notif = np; } /* * remove_notifier - remove a function from the list of things to * be called when something happens. */ void remove_notifier(notif, func, arg) struct notifier **notif; notify_func func; void *arg; { struct notifier *np; for (; (np = *notif) != 0; notif = &np->next) { if (np->func == func && np->arg == arg) { *notif = np->next; free(np); break; } } } /* * notify - call a set of functions registered with add_notify. */ void notify(notif, val) struct notifier *notif; int val; { struct notifier *np; while ((np = notif) != 0) { notif = np->next; (*np->func)(np->arg, val); } } /* * novm - log an error message saying we ran out of memory, and die. */ void novm(msg) char *msg; { fatal("Virtual memory exhausted allocating %s\n", msg); } /* * script_setenv - set an environment variable value to be used * for scripts that we run (e.g. ip-up, auth-up, etc.) */ void script_setenv(var, value, iskey) char *var, *value; int iskey; { size_t varl = strlen(var); size_t vl = varl + strlen(value) + 2; int i; char *p, *newstring; newstring = (char *) malloc(vl+1); if (newstring == 0) return; *newstring++ = iskey; slprintf(newstring, vl, "%s=%s", var, value); /* check if this variable is already set */ if (script_env != 0) { for (i = 0; (p = script_env[i]) != 0; ++i) { if (strncmp(p, var, varl) == 0 && p[varl] == '=') { if (p[-1] && pppdb != NULL) delete_db_key(p); free(p-1); script_env[i] = newstring; if (iskey && pppdb != NULL) add_db_key(newstring); update_db_entry(); return; } } } else { /* no space allocated for script env. ptrs. yet */ i = 0; script_env = (char **) malloc(16 * sizeof(char *)); if (script_env == 0) return; s_env_nalloc = 16; } /* reallocate script_env with more space if needed */ if (i + 1 >= s_env_nalloc) { int new_n = i + 17; char **newenv = (char **) realloc((void *)script_env, new_n * sizeof(char *)); if (newenv == 0) return; script_env = newenv; s_env_nalloc = new_n; } script_env[i] = newstring; script_env[i+1] = 0; if (pppdb != NULL) { if (iskey) add_db_key(newstring); update_db_entry(); } } /* * script_unsetenv - remove a variable from the environment * for scripts. */ void script_unsetenv(var) char *var; { int vl = strlen(var); int i; char *p; if (script_env == 0) return; for (i = 0; (p = script_env[i]) != 0; ++i) { if (strncmp(p, var, vl) == 0 && p[vl] == '=') { if (p[-1] && pppdb != NULL) delete_db_key(p); free(p-1); while ((script_env[i] = script_env[i+1]) != 0) ++i; break; } } if (pppdb != NULL) update_db_entry(); } /* * update_db_entry - update our entry in the database. */ static void update_db_entry() { TDB_DATA key, dbuf; int vlen, i; char *p, *q, *vbuf; if (script_env == NULL) return; vlen = 0; for (i = 0; (p = script_env[i]) != 0; ++i) vlen += strlen(p) + 1; vbuf = malloc(vlen); if (vbuf == 0) novm("database entry"); q = vbuf; for (i = 0; (p = script_env[i]) != 0; ++i) q += slprintf(q, vbuf + vlen - q, "%s;", p); key.dptr = db_key; key.dsize = strlen(db_key); dbuf.dptr = vbuf; dbuf.dsize = vlen; if (tdb_store(pppdb, key, dbuf, TDB_REPLACE)) error("tdb_store failed: %s", tdb_error(pppdb)); } /* * add_db_key - add a key that we can use to look up our database entry. */ static void add_db_key(str) const char *str; { TDB_DATA key, dbuf; key.dptr = (char *) str; key.dsize = strlen(str); dbuf.dptr = db_key; dbuf.dsize = strlen(db_key); if (tdb_store(pppdb, key, dbuf, TDB_REPLACE)) error("tdb_store key failed: %s", tdb_error(pppdb)); } /* * delete_db_key - delete a key for looking up our database entry. */ static void delete_db_key(str) const char *str; { TDB_DATA key; key.dptr = (char *) str; key.dsize = strlen(str); tdb_delete(pppdb, key); } /* * cleanup_db - delete all the entries we put in the database. */ static void cleanup_db() { TDB_DATA key; int i; char *p; key.dptr = db_key; key.dsize = strlen(db_key); tdb_delete(pppdb, key); for (i = 0; (p = script_env[i]) != 0; ++i) if (p[-1]) delete_db_key(p); }