/* * main.c - Point-to-Point Protocol main module * * Copyright (c) 1984-2000 Carnegie Mellon University. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in * the documentation and/or other materials provided with the * distribution. * * 3. The name "Carnegie Mellon University" must not be used to * endorse or promote products derived from this software without * prior written permission. For permission or any legal * details, please contact * Office of Technology Transfer * Carnegie Mellon University * 5000 Forbes Avenue * Pittsburgh, PA 15213-3890 * (412) 268-4387, fax: (412) 268-7395 * tech-transfer@andrew.cmu.edu * * 4. Redistributions of any form whatsoever must retain the following * acknowledgment: * "This product includes software developed by Computing Services * at Carnegie Mellon University (http://www.cmu.edu/computing/)." * * CARNEGIE MELLON UNIVERSITY DISCLAIMS ALL WARRANTIES WITH REGARD TO * THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY * AND FITNESS, IN NO EVENT SHALL CARNEGIE MELLON UNIVERSITY BE LIABLE * FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN * AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. * * Copyright (c) 1999-2020 Paul Mackerras. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * 2. The name(s) of the authors of this software must not be used to * endorse or promote products derived from this software without * prior written permission. * * 3. Redistributions of any form whatsoever must retain the following * acknowledgment: * "This product includes software developed by Paul Mackerras * ". * * THE AUTHORS OF THIS SOFTWARE DISCLAIM ALL WARRANTIES WITH REGARD TO * THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY * AND FITNESS, IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY * SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN * AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */ #ifdef HAVE_CONFIG_H #include "config.h" #endif #include #include #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 PPP_WITH_IPV6CP #include "ipv6cp.h" #endif #include "upap.h" #include "chap-new.h" #include "eap.h" #include "ccp.h" #include "ecp.h" #include "pathnames.h" #include "ppp-crypto.h" #ifdef PPP_WITH_TDB #include "tdb.h" #endif #ifdef PPP_WITH_CBCP #include "cbcp.h" #endif #ifdef AT_CHANGE #include "atcp.h" #endif /* interface vars */ char ifname[IFNAMSIZ]; /* 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; struct notifier *fork_notifier = 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 */ int ppp_session_number; /* Session number, for channels with such a concept (eg PPPoE) */ int childwait_done; /* have timed out waiting for children */ #ifdef PPP_WITH_TDB TDB_CONTEXT *pppdb; /* database for storing status etc. */ #endif char db_key[32]; int (*holdoff_hook)(void) = NULL; int (*new_phase_hook)(int) = NULL; void (*snoop_recv_hook)(unsigned char *p, int len) = NULL; void (*snoop_send_hook)(unsigned char *p, int len) = NULL; static int conn_running; /* we have a [dis]connector running */ static int fd_loop; /* fd for getting demand-dial packets */ int fd_devnull; /* fd for /dev/null */ int devfd = -1; /* fd of underlying device */ int fd_ppp = -1; /* fd for talking PPP */ int phase; /* where the link is at */ int kill_link; int asked_to_quit; int open_ccp_flag; int listen_time; int got_sigusr2; int got_sigterm; int got_sighup; static sigset_t signals_handled; static int waiting; static int sigpipe[2]; 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. */ static struct pppd_stats old_link_stats; struct pppd_stats link_stats; unsigned link_connect_time; int link_stats_valid; int error_count; bool bundle_eof; bool bundle_terminating; /* * We maintain a list of child process pids and * functions to call when they exit. */ struct subprocess { pid_t pid; char *prog; void (*done)(void *); void *arg; int killable; struct subprocess *next; }; static struct subprocess *children; /* Prototypes for procedures local to this file. */ static void setup_signals(void); static void create_pidfile(int pid); static void create_linkpidfile(int pid); static void cleanup(void); static void get_input(void); static void calltimeout(void); static struct timeval *timeleft(struct timeval *); static void kill_my_pg(int); static void hup(int); static void term(int); static void chld(int); static void toggle_debug(int); static void open_ccp(int); static void bad_signal(int); static void holdoff_end(void *); static void forget_child(int pid, int status); static int reap_kids(void); static void childwait_end(void *); #ifdef PPP_WITH_TDB static void update_db_entry(void); static void add_db_key(const char *); static void delete_db_key(const char *); static void cleanup_db(void); #endif static void handle_events(void); void print_link_stats(void); extern char *getlogin(void); int main(int, char *[]); /* * 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 PPP_WITH_CBCP &cbcp_protent, #endif &ipcp_protent, #ifdef PPP_WITH_IPV6CP &ipv6cp_protent, #endif &ccp_protent, &ecp_protent, #ifdef AT_CHANGE &atcp_protent, #endif &eap_protent, NULL }; int main(int argc, char *argv[]) { int i, t; char *p; struct passwd *pw; struct protent *protp; char numbuf[16]; PPP_crypto_init(); strlcpy(path_ipup, PPP_PATH_IPUP, MAXPATHLEN); strlcpy(path_ipdown, PPP_PATH_IPDOWN, MAXPATHLEN); #ifdef PPP_WITH_IPV6CP strlcpy(path_ipv6up, PPP_PATH_IPV6UP, MAXPATHLEN); strlcpy(path_ipv6down, PPP_PATH_IPV6DOWN, MAXPATHLEN); #endif link_stats_valid = 0; new_phase(PHASE_INITIALIZE); 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(PPP_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)); if (show_options) { showopts(); die(0); } /* * 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 PPP_WITH_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); /* Make sure fds 0, 1, 2 are open to somewhere. */ fd_devnull = open(PPP_DEVNULL, O_RDWR); if (fd_devnull < 0) fatal("Couldn't open %s: %m", PPP_DEVNULL); while (fd_devnull <= 2) { i = dup(fd_devnull); if (i < 0) fatal("Critical shortage of file descriptors: dup failed: %m"); fd_devnull = i; } /* * Initialize system-dependent stuff. */ sys_init(); #ifdef PPP_WITH_TDB pppdb = tdb_open(PPP_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", PPP_PATH_PPPDB); if (multilink) { warn("Warning: disabling multilink"); multilink = 0; } } #endif /* * 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(); create_linkpidfile(getpid()); waiting = 0; /* * 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. */ fd_loop = open_ppp_loopback(); set_ifunit(1); /* * Configure the interface and mark it up, etc. */ demand_conf(); } do_callback = 0; for (;;) { bundle_eof = 0; bundle_terminating = 0; 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 (asked_to_quit) break; if (get_loop_output()) break; } remove_fd(fd_loop); if (asked_to_quit) break; /* * Now we want to bring up the link. */ demand_block(); info("Starting link"); } get_time(&start_time); script_unsetenv("CONNECT_TIME"); script_unsetenv("BYTES_SENT"); script_unsetenv("BYTES_RCVD"); lcp_open(0); /* Start protocol */ start_link(0); while (phase != PHASE_DEAD) { handle_events(); get_input(); if (kill_link) lcp_close(0, "User request"); if (asked_to_quit) { bundle_terminating = 1; if (phase == PHASE_MASTER) mp_bundle_terminated(); } if (open_ccp_flag) { if (phase == PHASE_NETWORK || phase == PHASE_RUNNING) { ccp_fsm[0].flags = OPT_RESTART; /* clears OPT_SILENT */ (*ccp_protent.open)(0); } } } /* restore FSMs to original state */ lcp_close(0, ""); if (!persist || asked_to_quit || (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 */ reap_kids(); if (n_children > 0) { if (child_wait > 0) TIMEOUT(childwait_end, NULL, child_wait); 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); } while (n_children > 0 && !childwait_done) { handle_events(); if (kill_link && !childwait_done) childwait_end(NULL); } } PPP_crypto_deinit(); die(status); return 0; } /* * handle_events - wait for something to happen and respond to it. */ static void handle_events(void) { struct timeval timo; unsigned char buf[16]; kill_link = open_ccp_flag = 0; /* alert via signal pipe */ waiting = 1; /* flush signal pipe */ for (; read(sigpipe[0], buf, sizeof(buf)) > 0; ); add_fd(sigpipe[0]); /* wait if necessary */ if (!(got_sighup || got_sigterm || got_sigusr2 || got_sigchld)) wait_input(timeleft(&timo)); waiting = 0; remove_fd(sigpipe[0]); calltimeout(); if (got_sighup) { info("Hangup (SIGHUP)"); kill_link = 1; got_sighup = 0; if (status != EXIT_HANGUP) status = EXIT_USER_REQUEST; } if (got_sigterm) { info("Terminating on signal %d", got_sigterm); kill_link = 1; asked_to_quit = 1; persist = 0; status = EXIT_USER_REQUEST; got_sigterm = 0; } if (got_sigchld) { got_sigchld = 0; reap_kids(); /* Don't leave dead kids lying around */ } if (got_sigusr2) { open_ccp_flag = 1; got_sigusr2 = 0; } } /* * setup_signals - initialize signal handling. */ static void setup_signals(void) { struct sigaction sa; /* create pipe to wake up event handler from signal handler */ if (pipe(sigpipe) < 0) fatal("Couldn't create signal pipe: %m"); fcntl(sigpipe[0], F_SETFD, fcntl(sigpipe[0], F_GETFD) | FD_CLOEXEC); fcntl(sigpipe[1], F_SETFD, fcntl(sigpipe[1], F_GETFD) | FD_CLOEXEC); fcntl(sigpipe[0], F_SETFL, fcntl(sigpipe[0], F_GETFL) | O_NONBLOCK); fcntl(sigpipe[1], F_SETFL, fcntl(sigpipe[1], F_GETFL) | O_NONBLOCK); /* * 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(&signals_handled); sigaddset(&signals_handled, SIGHUP); sigaddset(&signals_handled, SIGINT); sigaddset(&signals_handled, SIGTERM); sigaddset(&signals_handled, SIGCHLD); sigaddset(&signals_handled, 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 = signals_handled; 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(int iskey) { char ifkey[32]; if (req_ifname[0] != '\0') slprintf(ifname, sizeof(ifname), "%s", req_ifname); else slprintf(ifname, sizeof(ifname), "%s%d", PPP_DRV_NAME, ifunit); info("Using interface %s", ifname); script_setenv("IFNAME", ifname, iskey); slprintf(ifkey, sizeof(ifkey), "%d", ifunit); script_setenv("UNIT", ifkey, iskey); if (iskey) { create_pidfile(getpid()); /* write pid to file */ create_linkpidfile(getpid()); } } /* * detach - detach us from the controlling terminal. */ void detach(void) { int pid; int ret; char numbuf[16]; int pipefd[2]; if (detached) return; if (pipe(pipefd) == -1) pipefd[0] = pipefd[1] = -1; if ((pid = fork()) < 0) { error("Couldn't detach (fork failed: %m)"); die(1); /* or just return? */ } if (pid != 0) { /* parent */ notify(pidchange, pid); /* update pid files if they have been written already */ if (pidfilename[0]) create_pidfile(pid); create_linkpidfile(pid); exit(0); /* parent dies */ } setsid(); ret = chdir("/"); if (ret != 0) { fatal("Could not change directory to '/', %m"); } dup2(fd_devnull, 0); dup2(fd_devnull, 1); dup2(fd_devnull, 2); detached = 1; if (log_default) log_to_fd = -1; slprintf(numbuf, sizeof(numbuf), "%d", getpid()); script_setenv("PPPD_PID", numbuf, 1); /* wait for parent to finish updating pid & lock files and die */ close(pipefd[1]); complete_read(pipefd[0], numbuf, 1); close(pipefd[0]); } /* * reopen_log - (re)open our connection to syslog. */ void reopen_log(void) { openlog("pppd", LOG_PID | LOG_NDELAY, LOG_PPP); setlogmask(LOG_UPTO(LOG_INFO)); } /* * Create a file containing our process ID. */ static void create_pidfile(int pid) { FILE *pidfile; slprintf(pidfilename, sizeof(pidfilename), "%s%s.pid", PPP_PATH_VARRUN, ifname); if ((pidfile = fopen(pidfilename, "w")) != NULL) { fprintf(pidfile, "%d\n", pid); (void) fclose(pidfile); } else { error("Failed to create pid file %s: %m", pidfilename); pidfilename[0] = 0; } } void create_linkpidfile(int pid) { FILE *pidfile; if (linkname[0] == 0) return; script_setenv("LINKNAME", linkname, 1); slprintf(linkpidfile, sizeof(linkpidfile), "%sppp-%s.pid", PPP_PATH_VARRUN, linkname); if ((pidfile = fopen(linkpidfile, "w")) != NULL) { fprintf(pidfile, "%d\n", pid); if (ifname[0]) fprintf(pidfile, "%s\n", ifname); (void) fclose(pidfile); } else { error("Failed to create pid file %s: %m", linkpidfile); linkpidfile[0] = 0; } } /* * remove_pidfile - remove our pid files */ void remove_pidfiles(void) { 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; } /* * holdoff_end - called via a timeout when the holdoff period ends. */ static void holdoff_end(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" }, { 0x51, "KNX Bridging Data" }, { 0x53, "Encryption" }, { 0x55, "Individual Link Encryption" }, { 0x57, "IPv6" }, { 0x59, "PPP Muxing" }, { 0x5b, "Vendor-Specific Network Protocol" }, { 0x61, "RTP IPHC Full Header" }, { 0x63, "RTP IPHC Compressed TCP" }, { 0x65, "RTP IPHC Compressed non-TCP" }, { 0x67, "RTP IPHC Compressed UDP 8" }, { 0x69, "RTP IPHC Compressed RTP 8" }, { 0x6f, "Stampede Bridging" }, { 0x73, "MP+" }, { 0xc1, "NTCITS IPI" }, { 0xfb, "single-link compression" }, { 0xfd, "Compressed Datagram" }, { 0x0201, "802.1d Hello Packets" }, { 0x0203, "IBM Source Routing BPDU" }, { 0x0205, "DEC LANBridge100 Spanning Tree" }, { 0x0207, "Cisco Discovery Protocol" }, { 0x0209, "Netcs Twin Routing" }, { 0x020b, "STP - Scheduled Transfer Protocol" }, { 0x020d, "EDP - Extreme Discovery Protocol" }, { 0x0211, "Optical Supervisory Channel Protocol" }, { 0x0213, "Optical Supervisory Channel Protocol" }, { 0x0231, "Luxcom" }, { 0x0233, "Sigma Network Systems" }, { 0x0235, "Apple Client Server Protocol" }, { 0x0281, "MPLS Unicast" }, { 0x0283, "MPLS Multicast" }, { 0x0285, "IEEE p1284.4 standard - data packets" }, { 0x0287, "ETSI TETRA Network Protocol Type 1" }, { 0x0289, "Multichannel Flow Treatment Protocol" }, { 0x2063, "RTP IPHC Compressed TCP No Delta" }, { 0x2065, "RTP IPHC Context State" }, { 0x2067, "RTP IPHC Compressed UDP 16" }, { 0x2069, "RTP IPHC Compressed RTP 16" }, { 0x4001, "Cray Communications Control Protocol" }, { 0x4003, "CDPD Mobile Network Registration Protocol" }, { 0x4005, "Expand accelerator protocol" }, { 0x4007, "ODSICP NCP" }, { 0x4009, "DOCSIS DLL" }, { 0x400B, "Cetacean Network Detection Protocol" }, { 0x4021, "Stacker LZS" }, { 0x4023, "RefTek Protocol" }, { 0x4025, "Fibre Channel" }, { 0x4027, "EMIT Protocols" }, { 0x405b, "Vendor-Specific Protocol (VSP)" }, { 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" }, { 0x8051, "KNX Bridging Control Protocol" }, { 0x8053, "Encryption Control Protocol" }, { 0x8055, "Individual Link Encryption Control Protocol" }, { 0x8057, "IPv6 Control Protocol" }, { 0x8059, "PPP Muxing Control Protocol" }, { 0x805b, "Vendor-Specific Network Control Protocol (VSNCP)" }, { 0x806f, "Stampede Bridging Control Protocol" }, { 0x8073, "MP+ Control Protocol" }, { 0x80c1, "NTCITS IPI Control Protocol" }, { 0x80fb, "Single Link Compression Control Protocol" }, { 0x80fd, "Compression Control Protocol" }, { 0x8207, "Cisco Discovery Protocol Control" }, { 0x8209, "Netcs Twin Routing" }, { 0x820b, "STP - Control Protocol" }, { 0x820d, "EDPCP - Extreme Discovery Protocol Ctrl Prtcl" }, { 0x8235, "Apple Client Server Protocol Control" }, { 0x8281, "MPLSCP" }, { 0x8285, "IEEE p1284.4 standard - Protocol Control" }, { 0x8287, "ETSI TETRA TNP1 Control Protocol" }, { 0x8289, "Multichannel Flow Treatment Protocol" }, { 0xc021, "Link Control Protocol" }, { 0xc023, "Password Authentication Protocol" }, { 0xc025, "Link Quality Report" }, { 0xc027, "Shiva Password Authentication Protocol" }, { 0xc029, "CallBack Control Protocol (CBCP)" }, { 0xc02b, "BACP Bandwidth Allocation Control Protocol" }, { 0xc02d, "BAP" }, { 0xc05b, "Vendor-Specific Authentication Protocol (VSAP)" }, { 0xc081, "Container Control Protocol" }, { 0xc223, "Challenge Handshake Authentication Protocol" }, { 0xc225, "RSA Authentication Protocol" }, { 0xc227, "Extensible Authentication Protocol" }, { 0xc229, "Mitsubishi Security Info Exch Ptcl (SIEP)" }, { 0xc26f, "Stampede Bridging Authorization Protocol" }, { 0xc281, "Proprietary Authentication Protocol" }, { 0xc283, "Proprietary Authentication Protocol" }, { 0xc481, "Proprietary Node ID Authentication Protocol" }, { 0, NULL }, }; /* * protocol_name - find a name for a PPP protocol. */ const char * protocol_name(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(void) { 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) { if (bundle_eof && multilink_master) { notice("Last channel has disconnected"); mp_bundle_terminated(); return; } notice("Modem hangup"); hungup = 1; status = EXIT_HANGUP; lcp_lowerdown(0); /* serial link is no longer available */ link_terminated(0); return; } if (len < PPP_HDRLEN) { dbglog("received short packet:%.*B", len, p); return; } dump_packet("rcvd", p, len); if (snoop_recv_hook) snoop_recv_hook(p, len); 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) { dbglog("Discarded 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 || protocol == PPP_EAP)) { dbglog("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); } /* * ppp_send_config - configure the transmit-side characteristics of * the ppp interface. Returns -1, indicating an error, if the channel * send_config procedure called error() (or incremented error_count * itself), otherwise 0. */ int ppp_send_config(int unit, int mtu, u_int32_t accm, int pcomp, int accomp) { int errs; if (the_channel->send_config == NULL) return 0; errs = error_count; (*the_channel->send_config)(mtu, accm, pcomp, accomp); return (error_count != errs)? -1: 0; } /* * ppp_recv_config - configure the receive-side characteristics of * the ppp interface. Returns -1, indicating an error, if the channel * recv_config procedure called error() (or incremented error_count * itself), otherwise 0. */ int ppp_recv_config(int unit, int mru, u_int32_t accm, int pcomp, int accomp) { int errs; if (the_channel->recv_config == NULL) return 0; errs = error_count; (*the_channel->recv_config)(mru, accm, pcomp, accomp); return (error_count != errs)? -1: 0; } /* * new_phase - signal the start of a new phase of pppd's operation. */ void new_phase(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(int status) { if (!doing_multilink || multilink_master) print_link_stats(); 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(void) { sys_cleanup(); if (fd_ppp >= 0) the_channel->disestablish_ppp(devfd); if (the_channel->cleanup) (*the_channel->cleanup)(); remove_pidfiles(); #ifdef PPP_WITH_TDB if (pppdb != NULL) cleanup_db(); #endif } void print_link_stats(void) { /* * 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); link_stats_valid = 0; } } /* * reset_link_stats - "reset" stats when link goes up. */ void reset_link_stats(int u) { if (!get_ppp_stats(u, &old_link_stats)) return; get_time(&start_time); } /* * update_link_stats - get stats at link termination. */ void update_link_stats(int u) { struct timeval now; char numbuf[32]; if (!get_ppp_stats(u, &link_stats) || get_time(&now) < 0) return; link_connect_time = now.tv_sec - start_time.tv_sec; link_stats_valid = 1; link_stats.bytes_in -= old_link_stats.bytes_in; link_stats.bytes_out -= old_link_stats.bytes_out; link_stats.pkts_in -= old_link_stats.pkts_in; link_stats.pkts_out -= old_link_stats.pkts_out; slprintf(numbuf, sizeof(numbuf), "%u", link_connect_time); script_setenv("CONNECT_TIME", numbuf, 0); snprintf(numbuf, sizeof(numbuf), "%" PRIu64, link_stats.bytes_out); script_setenv("BYTES_SENT", numbuf, 0); snprintf(numbuf, sizeof(numbuf), "%" PRIu64, 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)(void *); /* routine */ struct callout *c_next; }; static struct callout *callout = NULL; /* Callout list */ static struct timeval timenow; /* Current time */ /* * timeout - Schedule a timeout. */ void timeout(void (*func)(void *), void *arg, int secs, int usecs) { struct callout *newp, *p, **pp; /* * 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; get_time(&timenow); 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(void (*func)(void *), void *arg) { struct callout **copp, *freep; /* * 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(void) { struct callout *p; while (callout != NULL) { p = callout; if (get_time(&timenow) < 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(struct timeval *tvp) { if (callout == NULL) return NULL; get_time(&timenow); 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. * We assume that sig is currently blocked. */ static void kill_my_pg(int sig) { struct sigaction act, oldact; struct subprocess *chp; if (!detached) { /* * There might be other things in our process group that we * didn't start that would get hit if we did a kill(0), so * just send the signal individually to our children. */ for (chp = children; chp != NULL; chp = chp->next) if (chp->killable) kill(chp->pid, sig); return; } /* We've done a setsid(), so we can just use a kill(0) */ sigemptyset(&act.sa_mask); /* unnecessary in fact */ act.sa_handler = SIG_IGN; act.sa_flags = 0; kill(0, sig); /* * The kill() above made the signal pending for us, as well as * the rest of our process group, but we don't want it delivered * to us. It is blocked at the moment. Setting it to be ignored * will cause the pending signal to be discarded. If we did the * kill() after setting the signal to be ignored, it is unspecified * (by POSIX) whether the signal is immediately discarded or left * pending, and in fact Linux would leave it pending, and so it * would be delivered after the current signal handler exits, * leading to an infinite loop. */ 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(int sig) { /* can't log a message here, it can deadlock */ 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) { #pragma GCC diagnostic push #pragma GCC diagnostic ignored "-Wunused-result" write(sigpipe[1], &sig, sizeof(sig)); #pragma GCC diagnostic pop } } /* * term - Catch SIGTERM signal and SIGINT signal (^C/del). * * Indicates that we should initiate a graceful disconnect and exit. */ /*ARGSUSED*/ static void term(int sig) { /* can't log a message here, it can deadlock */ got_sigterm = sig; if (conn_running) /* Send the signal to the [dis]connector process(es) also */ kill_my_pg(sig); notify(sigreceived, sig); if (waiting) { #pragma GCC diagnostic push #pragma GCC diagnostic ignored "-Wunused-result" write(sigpipe[1], &sig, sizeof(sig)); #pragma GCC diagnostic pop } } /* * chld - Catch SIGCHLD signal. * Sets a flag so we will call reap_kids in the mainline. */ static void chld(int sig) { got_sigchld = 1; if (waiting) { #pragma GCC diagnostic push #pragma GCC diagnostic ignored "-Wunused-result" write(sigpipe[1], &sig, sizeof(sig)); #pragma GCC diagnostic pop } } /* * toggle_debug - Catch SIGUSR1 signal. * * Toggle debug flag. */ /*ARGSUSED*/ static void toggle_debug(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(int sig) { got_sigusr2 = 1; if (waiting) { #pragma GCC diagnostic push #pragma GCC diagnostic ignored "-Wunused-result" write(sigpipe[1], &sig, sizeof(sig)); #pragma GCC diagnostic pop } } /* * bad_signal - We've caught a fatal signal. Clean up state and exit. */ static void bad_signal(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); } /* * safe_fork - Create a child process. The child closes all the * file descriptors that we don't want to leak to a script. * The parent waits for the child to do this before returning. * This also arranges for the specified fds to be dup'd to * fds 0, 1, 2 in the child. */ pid_t safe_fork(int infd, int outfd, int errfd) { pid_t pid; int fd, pipefd[2]; char buf[1]; /* make sure fds 0, 1, 2 are occupied (probably not necessary) */ while ((fd = dup(fd_devnull)) >= 0) { if (fd > 2) { close(fd); break; } } if (pipe(pipefd) == -1) pipefd[0] = pipefd[1] = -1; pid = fork(); if (pid < 0) { error("fork failed: %m"); return -1; } if (pid > 0) { /* parent */ close(pipefd[1]); /* this read() blocks until the close(pipefd[1]) below */ complete_read(pipefd[0], buf, 1); close(pipefd[0]); return pid; } /* Executing in the child */ sys_close(); #ifdef PPP_WITH_TDB if (pppdb != NULL) tdb_close(pppdb); #endif /* make sure infd, outfd and errfd won't get tromped on below */ if (infd == 1 || infd == 2) infd = dup(infd); if (outfd == 0 || outfd == 2) outfd = dup(outfd); if (errfd == 0 || errfd == 1) errfd = dup(errfd); closelog(); /* dup the in, out, err fds to 0, 1, 2 */ if (infd != 0) dup2(infd, 0); if (outfd != 1) dup2(outfd, 1); if (errfd != 2) dup2(errfd, 2); if (log_to_fd > 2) close(log_to_fd); if (the_channel->close) (*the_channel->close)(); else close(devfd); /* some plugins don't have a close function */ close(fd_ppp); close(fd_devnull); if (infd != 0) close(infd); if (outfd != 1) close(outfd); if (errfd != 2) close(errfd); notify(fork_notifier, 0); close(pipefd[0]); /* this close unblocks the read() call above in the parent */ close(pipefd[1]); return 0; } static bool add_script_env(int pos, char *newstring) { if (pos + 1 >= s_env_nalloc) { int new_n = pos + 17; char **newenv = realloc(script_env, new_n * sizeof(char *)); if (newenv == NULL) { free(newstring - 1); return 0; } script_env = newenv; s_env_nalloc = new_n; } script_env[pos] = newstring; script_env[pos + 1] = NULL; return 1; } static void remove_script_env(int pos) { free(script_env[pos] - 1); while ((script_env[pos] = script_env[pos + 1]) != NULL) pos++; } /* * update_system_environment - process the list of set/unset options * and update the system environment. */ static void update_system_environment(void) { struct userenv *uep; for (uep = userenv_list; uep != NULL; uep = uep->ue_next) { if (uep->ue_isset) setenv(uep->ue_name, uep->ue_value, 1); else unsetenv(uep->ue_name); } } /* * 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 PPP_PATH_CONNERRS file. */ int device_script(char *program, int in, int out, int dont_wait) { int pid; int status = -1; int errfd; int ret; if (log_to_fd >= 0) errfd = log_to_fd; else errfd = open(PPP_PATH_CONNERRS, O_WRONLY | O_APPEND | O_CREAT, 0644); ++conn_running; pid = safe_fork(in, out, errfd); if (pid != 0 && log_to_fd < 0) close(errfd); if (pid < 0) { --conn_running; error("Failed to create child process: %m"); return -1; } if (pid != 0) { record_child(pid, program, NULL, NULL, 1); status = 0; if (!dont_wait) { while (waitpid(pid, &status, 0) < 0) { if (errno == EINTR) continue; fatal("error waiting for (dis)connection process: %m"); } forget_child(pid, status); --conn_running; } return (status == 0 ? 0 : -1); } /* here we are executing in the child */ ret = setgid(getgid()); if (ret != 0) { perror("pppd: setgid failed\n"); exit(1); } ret = setuid(uid); if (ret != 0 || getuid() != uid) { perror("pppd: setuid failed\n"); exit(1); } update_system_environment(); execl("/bin/sh", "sh", "-c", program, (char *)0); perror("pppd: could not exec /bin/sh"); _exit(99); /* NOTREACHED */ } /* * update_script_environment - process the list of set/unset options * and update the script environment. Note that we intentionally do * not update the TDB. These changes are layered on top right before * exec. It is not possible to use script_setenv() or * script_unsetenv() safely after this routine is run. */ static void update_script_environment(void) { struct userenv *uep; for (uep = userenv_list; uep != NULL; uep = uep->ue_next) { int i; char *p, *newstring; int nlen = strlen(uep->ue_name); for (i = 0; (p = script_env[i]) != NULL; i++) { if (strncmp(p, uep->ue_name, nlen) == 0 && p[nlen] == '=') break; } if (uep->ue_isset) { nlen += strlen(uep->ue_value) + 2; newstring = malloc(nlen + 1); if (newstring == NULL) continue; *newstring++ = 0; slprintf(newstring, nlen, "%s=%s", uep->ue_name, uep->ue_value); if (p != NULL) script_env[i] = newstring; else add_script_env(i, newstring); } else if (p != NULL) { remove_script_env(i); } } } /* * run_program - execute a program with given arguments, * but don't wait for it unless wait is non-zero. * 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(char *prog, char **args, int must_exist, void (*done)(void *), void *arg, int wait) { int pid, status, ret; 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 = safe_fork(fd_devnull, fd_devnull, fd_devnull); if (pid == -1) { error("Failed to create child process for %s: %m", prog); return -1; } if (pid != 0) { if (debug) dbglog("Script %s started (pid %d)", prog, pid); record_child(pid, prog, done, arg, 0); if (wait) { while (waitpid(pid, &status, 0) < 0) { if (errno == EINTR) continue; fatal("error waiting for script %s: %m", prog); } forget_child(pid, status); } return pid; } /* Leave the current location */ (void) setsid(); /* No controlling tty. */ (void) umask (S_IRWXG|S_IRWXO); ret = chdir ("/"); /* no current directory. */ if (ret != 0) { fatal("Failed to change directory to '/', %m"); } ret = setuid(0); /* set real UID = root */ if (ret != 0) { fatal("Failed to set uid, %m"); } ret = setgid(getegid()); if (ret != 0) { fatal("failed to set gid, %m"); } #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 /* run the program */ update_script_environment(); 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(99); } /* * record_child - add a child process to the list for reap_kids * to use. */ void record_child(int pid, char *prog, void (*done)(void *), void *arg, int killable) { 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; chp->killable = killable; children = chp; } } /* * childwait_end - we got fed up waiting for the child processes to * exit, send them all a SIGTERM. */ static void childwait_end(void *arg) { struct subprocess *chp; for (chp = children; chp != NULL; chp = chp->next) { if (debug) dbglog("sending SIGTERM to process %d", chp->pid); kill(chp->pid, SIGTERM); } childwait_done = 1; } /* * forget_child - clean up after a dead child */ static void forget_child(int pid, int status) { struct subprocess *chp, **prevp; 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, WIFEXITED(status) ? WEXITSTATUS(status) : status); if (chp && chp->done) (*chp->done)(chp->arg); if (chp) free(chp); } /* * reap_kids - get status from any dead child processes, * and log a message for abnormal terminations. */ static int reap_kids(void) { int pid, status; if (n_children == 0) return 0; while ((pid = waitpid(-1, &status, WNOHANG)) != -1 && pid != 0) { forget_child(pid, status); } 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(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(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_notifier. */ void notify(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(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(char *var, char *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] == '=') { #ifdef PPP_WITH_TDB if (p[-1] && pppdb != NULL) delete_db_key(p); #endif free(p-1); script_env[i] = newstring; #ifdef PPP_WITH_TDB if (pppdb != NULL) { if (iskey) add_db_key(newstring); update_db_entry(); } #endif return; } } } else { /* no space allocated for script env. ptrs. yet */ i = 0; script_env = malloc(16 * sizeof(char *)); if (script_env == 0) { free(newstring - 1); return; } s_env_nalloc = 16; } if (!add_script_env(i, newstring)) return; #ifdef PPP_WITH_TDB if (pppdb != NULL) { if (iskey) add_db_key(newstring); update_db_entry(); } #endif } /* * script_unsetenv - remove a variable from the environment * for scripts. */ void script_unsetenv(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] == '=') { #ifdef PPP_WITH_TDB if (p[-1] && pppdb != NULL) delete_db_key(p); #endif remove_script_env(i); break; } } #ifdef PPP_WITH_TDB if (pppdb != NULL) update_db_entry(); #endif } /* * Any arbitrary string used as a key for locking the database. * It doesn't matter what it is as long as all pppds use the same string. */ #define PPPD_LOCK_KEY "pppd lock" /* * lock_db - get an exclusive lock on the TDB database. * Used to ensure atomicity of various lookup/modify operations. */ void lock_db(void) { #ifdef PPP_WITH_TDB TDB_DATA key; key.dptr = PPPD_LOCK_KEY; key.dsize = strlen(key.dptr); tdb_chainlock(pppdb, key); #endif } /* * unlock_db - remove the exclusive lock obtained by lock_db. */ void unlock_db(void) { #ifdef PPP_WITH_TDB TDB_DATA key; key.dptr = PPPD_LOCK_KEY; key.dsize = strlen(key.dptr); tdb_chainunlock(pppdb, key); #endif } #ifdef PPP_WITH_TDB /* * update_db_entry - update our entry in the database. */ static void update_db_entry(void) { 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 + 1); 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_errorstr(pppdb)); if (vbuf) free(vbuf); } /* * add_db_key - add a key that we can use to look up our database entry. */ static void add_db_key(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_errorstr(pppdb)); } /* * delete_db_key - delete a key for looking up our database entry. */ static void delete_db_key(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(void) { 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); } #endif /* PPP_WITH_TDB */