X-Git-Url: http://git.ozlabs.org/?p=ppp.git;a=blobdiff_plain;f=pppd%2Fmain.c;h=37ad65f5a4c7ae50000175368c2d79f92998bec8;hp=2b25753214ba0fdbecc86be80c884707c5c45727;hb=1fae28ce79350b03f0cf8a69ad06dd68637cd6b1;hpb=657d25368327ffc4005727412a540d4eead35510 diff --git a/pppd/main.c b/pppd/main.c index 2b25753..37ad65f 100644 --- a/pppd/main.c +++ b/pppd/main.c @@ -18,10 +18,11 @@ */ #ifndef lint -static char rcsid[] = "$Id: main.c,v 1.32 1996/04/04 03:59:33 paulus Exp $"; +static char rcsid[] = "$Id: main.c,v 1.58 1999/03/12 06:07:18 paulus Exp $"; #endif #include +#include #include #include #include @@ -32,6 +33,7 @@ static char rcsid[] = "$Id: main.c,v 1.32 1996/04/04 03:59:33 paulus Exp $"; #include #include #include +#include #include #include #include @@ -39,7 +41,6 @@ static char rcsid[] = "$Id: main.c,v 1.32 1996/04/04 03:59:33 paulus Exp $"; #include #include #include -#include #include "pppd.h" #include "magic.h" @@ -52,20 +53,23 @@ static char rcsid[] = "$Id: main.c,v 1.32 1996/04/04 03:59:33 paulus Exp $"; #include "pathnames.h" #include "patchlevel.h" +#ifdef CBCP_SUPPORT +#include "cbcp.h" +#endif + +#if defined(SUNOS4) +extern char *strerror(); +#endif + #ifdef IPX_CHANGE #include "ipxcp.h" #endif /* IPX_CHANGE */ - -/* - * If REQ_SYSOPTIONS is defined to 1, pppd will not run unless - * /etc/ppp/options exists. - */ -#ifndef REQ_SYSOPTIONS -#define REQ_SYSOPTIONS 1 +#ifdef AT_CHANGE +#include "atcp.h" #endif /* interface vars */ -char ifname[IFNAMSIZ]; /* Interface name */ +char ifname[32]; /* Interface name */ int ifunit; /* Interface unit number */ char *progname; /* Name of this program */ @@ -74,33 +78,47 @@ static char pidfilename[MAXPATHLEN]; /* name of pid file */ static char default_devnam[MAXPATHLEN]; /* name of default device */ static pid_t pid; /* Our pid */ static uid_t uid; /* Our real user-id */ +static int conn_running; /* we have a [dis]connector running */ int ttyfd = -1; /* Serial port file descriptor */ +mode_t tty_mode = -1; /* Original access permissions to tty */ +int baud_rate; /* Actual bits/second for serial device */ +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 */ int phase; /* where the link is at */ int kill_link; int open_ccp_flag; +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 */ -int hungup; /* terminal has been hung up */ static int n_children; /* # child processes still running */ -int baud_rate; /* Actual bits/second for serial device */ - static int locked; /* lock() has succeeded */ 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 */ + /* Prototypes for procedures local to this file. */ +static void create_pidfile __P((void)); static void cleanup __P((void)); static void close_tty __P((void)); static void get_input __P((void)); -static void connect_time_expired __P((caddr_t)); 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)); @@ -114,12 +132,17 @@ static void pr_log __P((void *, char *, ...)); 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. @@ -129,10 +152,16 @@ struct protent *protocols[] = { &lcp_protent, &pap_protent, &chap_protent, +#ifdef CBCP_SUPPORT + &cbcp_protent, +#endif &ipcp_protent, &ccp_protent, #ifdef IPX_CHANGE &ipxcp_protent, +#endif +#ifdef AT_CHANGE + &atcp_protent, #endif NULL }; @@ -142,84 +171,118 @@ main(argc, argv) int argc; char *argv[]; { - int i, nonblock, fdflags; + int i, fdflags; struct sigaction sa; - FILE *pidfile; char *p; struct passwd *pw; struct timeval timo; sigset_t mask; struct protent *protp; + struct stat statbuf; + char numbuf[16]; + phase = PHASE_INITIALIZE; p = ttyname(0); if (p) - strcpy(devnam, p); - strcpy(default_devnam, devnam); + strlcpy(devnam, sizeof(devnam), p); + strlcpy(default_devnam, sizeof(default_devnam), devnam); + + script_env = NULL; + + /* Initialize syslog facilities */ +#ifdef ULTRIX + openlog("pppd", LOG_PID); +#else + openlog("pppd", LOG_PID | LOG_NDELAY, LOG_PPP); + setlogmask(LOG_UPTO(LOG_INFO)); +#endif if (gethostname(hostname, MAXNAMELEN) < 0 ) { - perror("couldn't get hostname"); - die(1); + option_error("Couldn't get hostname: %m"); + exit(1); } hostname[MAXNAMELEN-1] = 0; uid = getuid(); + privileged = uid == 0; + sprintf(numbuf, "%d", uid); + script_setenv("ORIG_UID", numbuf); + + ngroups = getgroups(NGROUPS_MAX, groups); /* * Initialize to the standard option set, then parse, in order, - * the system options file, the user's options file, and the command - * line arguments. + * the system options file, the user's options file, + * the tty's options file, and the command line arguments. */ for (i = 0; (protp = protocols[i]) != NULL; ++i) (*protp->init)(0); - + progname = *argv; - if (!options_from_file(_PATH_SYSOPTIONS, REQ_SYSOPTIONS, 0) || - !options_for_tty() || - !options_from_user() || - !parse_args(argc-1, argv+1)) + if (!options_from_file(_PATH_SYSOPTIONS, !privileged, 0, 1) + || !options_from_user()) + exit(1); + scan_args(argc-1, argv+1); /* look for tty name on command line */ + if (!options_for_tty() + || !parse_args(argc-1, argv+1)) exit(1); + /* + * 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(1); + } + if (!ppp_available()) { - fprintf(stderr, no_ppp_msg); + option_error(no_ppp_msg); exit(1); } /* * Check that the options given are valid and consistent. */ - sys_check_options(); + if (!sys_check_options()) + exit(1); auth_check_options(); for (i = 0; (protp = protocols[i]) != NULL; ++i) if (protp->check_options != NULL) (*protp->check_options)(); if (demand && connector == 0) { - fprintf(stderr, "%s: connect script required for demand-dialling\n", - progname); + option_error("connect script is required for demand-dialling\n"); exit(1); } + script_setenv("DEVICE", devnam); + sprintf(numbuf, "%d", baud_rate); + script_setenv("SPEED", numbuf); + /* * If the user has specified the default device name explicitly, * pretend they hadn't. */ if (!default_device && strcmp(devnam, default_devnam) == 0) default_device = 1; + if (default_device) + nodetach = 1; /* * Initialize system-dependent stuff and magic number package. */ sys_init(); magic_init(); + if (debug) + setlogmask(LOG_UPTO(LOG_DEBUG)); /* * Detach ourselves from the terminal, if required, * and identify who is running us. */ - if (!default_device && !nodetach && daemon(0, 0) < 0) { - perror("Couldn't detach from controlling terminal"); - exit(1); - } + if (!nodetach && !updetach) + detach(); pid = getpid(); p = getlogin(); if (p == NULL) { @@ -229,8 +292,8 @@ main(argc, argv) else p = "(unknown)"; } - syslog(LOG_NOTICE, "pppd %s.%d started by %s, uid %d", - VERSION, PATCHLEVEL, p, uid); + syslog(LOG_NOTICE, "pppd %s.%d%s started by %s, uid %d", + VERSION, PATCHLEVEL, IMPLEMENTATION, p, uid); /* * Compute mask of all interesting signals and install signal handlers @@ -242,14 +305,13 @@ main(argc, argv) sigaddset(&mask, SIGINT); sigaddset(&mask, SIGTERM); sigaddset(&mask, SIGCHLD); + sigaddset(&mask, SIGUSR2); -#define SIGNAL(s, handler) { \ +#define SIGNAL(s, handler) do { \ sa.sa_handler = handler; \ - if (sigaction(s, &sa, NULL) < 0) { \ - syslog(LOG_ERR, "Couldn't establish signal handler (%d): %m", s); \ - die(1); \ - } \ - } + 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; @@ -300,6 +362,15 @@ main(argc, argv) 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); + + waiting = 0; + /* * If we're doing dial-on-demand, set up the interface now. */ @@ -311,16 +382,9 @@ main(argc, argv) syslog(LOG_INFO, "Using interface ppp%d", ifunit); (void) sprintf(ifname, "ppp%d", ifunit); + script_setenv("IFNAME", ifname); - /* write pid to file */ - (void) sprintf(pidfilename, "%s%s.pid", _PATH_VARRUN, ifname); - if ((pidfile = fopen(pidfilename, "w")) != NULL) { - fprintf(pidfile, "%d\n", pid); - (void) fclose(pidfile); - } else { - syslog(LOG_ERR, "Failed to create pid file %s: %m", pidfilename); - pidfilename[0] = 0; - } + create_pidfile(); /* write pid to file */ /* * Configure the interface and mark it up, etc. @@ -330,31 +394,45 @@ main(argc, argv) for (;;) { + need_holdoff = 1; + if (demand) { /* * Don't do anything until we see some activity. */ - phase = PHASE_DORMANT; kill_link = 0; + phase = PHASE_DORMANT; demand_unblock(); for (;;) { - wait_loop_output(timeleft(&timo)); + if (sigsetjmp(sigjmp, 1) == 0) { + sigprocmask(SIG_BLOCK, &mask, NULL); + if (kill_link) { + sigprocmask(SIG_UNBLOCK, &mask, NULL); + } else { + waiting = 1; + sigprocmask(SIG_UNBLOCK, &mask, NULL); + wait_loop_output(timeleft(&timo)); + } + } + waiting = 0; calltimeout(); if (kill_link) { if (!persist) - die(0); + break; kill_link = 0; } if (get_loop_output()) break; reap_kids(); } + if (kill_link && !persist) + break; /* * Now we want to bring up the link. */ demand_block(); - syslog(LOG_INFO, "Starting link"); + info("Starting link"); } /* @@ -368,55 +446,95 @@ main(argc, argv) /* * Open the serial device and set it up to be the ppp interface. - * If we're dialling out, or we don't want to use the modem lines, - * we open it in non-blocking mode, but then we need to clear - * the non-blocking I/O bit. + * First we open it in non-blocking mode so we can set the + * various termios flags appropriately. If we aren't dialling + * out and we want to use the modem lines, we reopen it later + * in order to wait for the carrier detect signal from the modem. */ - nonblock = (connector || !modem)? O_NONBLOCK: 0; - if ((ttyfd = open(devnam, nonblock | O_RDWR, 0)) < 0) { - syslog(LOG_ERR, "Failed to open %s: %m", devnam); - goto fail; - } - if (nonblock) { - if ((fdflags = fcntl(ttyfd, F_GETFL)) == -1 - || fcntl(ttyfd, F_SETFL, fdflags & ~O_NONBLOCK) < 0) - syslog(LOG_WARNING, - "Couldn't reset non-blocking mode on device: %m"); - } hungup = 0; kill_link = 0; + for (;;) { + /* If the user specified the device name, become the + user before opening it. */ + if (!devnam_info.priv) + seteuid(uid); + ttyfd = open(devnam, O_NONBLOCK | O_RDWR, 0); + if (!devnam_info.priv) + seteuid(0); + if (ttyfd >= 0) + break; + if (errno != EINTR) + error("Failed to open %s: %m", devnam); + if (!persist || errno != EINTR) + goto fail; + } + if ((fdflags = fcntl(ttyfd, F_GETFL)) == -1 + || fcntl(ttyfd, F_SETFL, fdflags & ~O_NONBLOCK) < 0) + warn("Couldn't reset non-blocking mode on device: %m"); + + /* + * Do the equivalent of `mesg n' to stop broadcast messages. + */ + if (fstat(ttyfd, &statbuf) < 0 + || fchmod(ttyfd, statbuf.st_mode & ~(S_IWGRP | S_IWOTH)) < 0) { + warn("Couldn't restrict write permissions to %s: %m", devnam); + } else + tty_mode = statbuf.st_mode; /* run connection script */ if (connector && connector[0]) { MAINDEBUG((LOG_INFO, "Connecting with <%s>", connector)); - /* set line speed, flow control, etc.; set CLOCAL for now */ - set_up_tty(ttyfd, 1); - - /* drop dtr to hang up in case modem is off hook */ if (!default_device && modem) { - setdtr(ttyfd, FALSE); + hangup_modem(ttyfd); /* in case modem is off hook */ sleep(1); - setdtr(ttyfd, TRUE); } + /* + * Set line speed, flow control, etc. + * On most systems we set CLOCAL for now so that we can talk + * to the modem before carrier comes up. But this has the + * side effect that we might miss it if CD drops before we + * get to clear CLOCAL below. On systems where we can talk + * successfully to the modem with CLOCAL clear and CD down, + * we could clear CLOCAL at this point. + */ + set_up_tty(ttyfd, 1); + if (device_script(connector, ttyfd, ttyfd) < 0) { - syslog(LOG_ERR, "Connect script failed"); - setdtr(ttyfd, FALSE); + error("Connect script failed"); goto fail; } - syslog(LOG_INFO, "Serial connection established."); + info("Serial connection established."); sleep(1); /* give it time to set up its terminal */ } /* set line speed, flow control, etc.; clear CLOCAL if modem option */ set_up_tty(ttyfd, 0); + /* reopen tty if necessary to wait for carrier */ + if (connector == NULL && modem) { + for (;;) { + if (!devnam_info.priv) + seteuid(uid); + i = open(devnam, O_RDWR); + if (!devnam_info.priv) + seteuid(0); + if (i >= 0) + break; + if (errno != EINTR) + error("Failed to reopen %s: %m", devnam); + if (!persist || errno != EINTR || hungup || kill_link) + goto fail; + } + close(i); + } + /* run welcome script, if any */ if (welcomer && welcomer[0]) { if (device_script(welcomer, ttyfd, ttyfd) < 0) - syslog(LOG_WARNING, "Welcome script failed"); + warn("Welcome script failed"); } /* set up the serial device as a ppp interface */ @@ -424,48 +542,45 @@ main(argc, argv) if (!demand) { - syslog(LOG_INFO, "Using interface ppp%d", ifunit); + info("Using interface ppp%d", ifunit); (void) sprintf(ifname, "ppp%d", ifunit); - - /* write pid to file */ - (void) sprintf(pidfilename, "%s%s.pid", _PATH_VARRUN, ifname); - if ((pidfile = fopen(pidfilename, "w")) != NULL) { - fprintf(pidfile, "%d\n", pid); - (void) fclose(pidfile); - } else { - syslog(LOG_ERR, "Failed to create pid file %s: %m", - pidfilename); - pidfilename[0] = 0; - } - } + script_setenv("IFNAME", ifname); - /* - * Set a timeout to close the connection once the maximum - * connect time has expired. - */ - if (maxconnect > 0) - TIMEOUT(connect_time_expired, 0, maxconnect); + create_pidfile(); /* write pid to file */ + } /* * Start opening the connection and wait for * incoming events (reply, timeout, etc.). */ + if (kill_link) + goto fail; syslog(LOG_NOTICE, "Connect: %s <--> %s", ifname, devnam); lcp_lowerup(0); lcp_open(0); /* Start protocol */ + open_ccp_flag = 0; for (phase = PHASE_ESTABLISH; phase != PHASE_DEAD; ) { - wait_input(timeleft(&timo)); + if (sigsetjmp(sigjmp, 1) == 0) { + sigprocmask(SIG_BLOCK, &mask, NULL); + if (kill_link || open_ccp_flag) { + sigprocmask(SIG_UNBLOCK, &mask, NULL); + } else { + waiting = 1; + sigprocmask(SIG_UNBLOCK, &mask, NULL); + wait_input(timeleft(&timo)); + } + } + waiting = 0; calltimeout(); - get_input(); if (kill_link) { lcp_close(0, "User request"); - phase = PHASE_TERMINATE; kill_link = 0; } + get_input(); if (open_ccp_flag) { if (phase == PHASE_NETWORK) { ccp_fsm[0].flags = OPT_RESTART; /* clears OPT_SILENT */ - ccp_open(0); + (*ccp_protent.open)(0); } open_ccp_flag = 0; } @@ -489,48 +604,106 @@ main(argc, argv) if (disconnector && !hungup) { set_up_tty(ttyfd, 1); if (device_script(disconnector, ttyfd, ttyfd) < 0) { - syslog(LOG_WARNING, "disconnect script failed"); + warn("disconnect script failed"); } else { - syslog(LOG_INFO, "Serial link disconnected."); + info("Serial link disconnected."); } } fail: - close_tty(); + if (ttyfd >= 0) + close_tty(); if (locked) { unlock(); locked = 0; } if (!demand) { - if (unlink(pidfilename) < 0 && errno != ENOENT) - syslog(LOG_WARNING, "unable to delete pid file: %m"); + if (pidfilename[0] != 0 + && unlink(pidfilename) < 0 && errno != ENOENT) + warn("unable to delete pid file: %m"); pidfilename[0] = 0; } if (!persist) break; + kill_link = 0; if (demand) demand_discard(); - if (holdoff > 0) { + if (holdoff > 0 && need_holdoff) { phase = PHASE_HOLDOFF; TIMEOUT(holdoff_end, NULL, holdoff); do { - wait_time(timeleft(&timo)); + if (sigsetjmp(sigjmp, 1) == 0) { + sigprocmask(SIG_BLOCK, &mask, NULL); + if (kill_link) { + sigprocmask(SIG_UNBLOCK, &mask, NULL); + } else { + waiting = 1; + sigprocmask(SIG_UNBLOCK, &mask, NULL); + wait_time(timeleft(&timo)); + } + } + waiting = 0; calltimeout(); if (kill_link) { - if (!persist) - die(0); kill_link = 0; phase = PHASE_DORMANT; /* allow signal to end holdoff */ } reap_kids(); } while (phase == PHASE_HOLDOFF); + if (!persist) + break; } } + /* Wait for scripts to finish */ + while (n_children > 0) + reap_kids(); + die(0); + return 0; +} + +/* + * detach - detach us from the controlling terminal. + */ +void +detach() +{ + if (detached) + return; + if (daemon(0, 0) < 0) { + perror("Couldn't detach from controlling terminal"); + die(1); + } + detached = 1; + pid = getpid(); + /* update pid file if it has been written already */ + if (pidfilename[0]) + create_pidfile(); +} + +/* + * Create a file containing our process ID. + */ +static void +create_pidfile() +{ + FILE *pidfile; + char numbuf[16]; + + (void) sprintf(pidfilename, "%s%s.pid", _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; + } + sprintf(numbuf, "%d", pid); + script_setenv("PPPD_PID", numbuf); } /* @@ -561,7 +734,7 @@ get_input() return; if (len == 0) { - syslog(LOG_NOTICE, "Modem hangup"); + notice("Modem hangup"); hungup = 1; lcp_lowerdown(0); /* serial link is no longer available */ link_terminated(0); @@ -569,7 +742,7 @@ get_input() } if (debug /*&& (debugflags & DBG_INPACKET)*/) - log_packet(p, len, "rcvd "); + log_packet(p, len, "rcvd ", LOG_DEBUG); if (len < PPP_HDRLEN) { MAINDEBUG((LOG_INFO, "io(): Received short packet.")); @@ -585,7 +758,19 @@ get_input() */ if (protocol != PPP_LCP && lcp_fsm[0].state != OPENED) { MAINDEBUG((LOG_INFO, - "io(): Received non-LCP packet when LCP not open.")); + "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((LOG_INFO, "get_input: discarding proto 0x%x in phase %d", + protocol, phase)); return; } @@ -605,7 +790,7 @@ get_input() } if (debug) - syslog(LOG_WARNING, "Unsupported protocol (0x%x) received", protocol); + warn("Unsupported protocol (0x%x) received", protocol); lcp_sprotrej(0, p - PPP_HDRLEN, len + PPP_HDRLEN); } @@ -631,19 +816,6 @@ die(status) exit(status); } -/* - * connect_time_expired - log a message and close the connection. - */ -static void -connect_time_expired(arg) - caddr_t arg; -{ - syslog(LOG_INFO, "Connect time expired"); - - phase = PHASE_TERMINATE; - lcp_close(0, "Connect time expired"); /* Close connection */ -} - /* * cleanup - restore anything which needs to be restored before we exit */ @@ -657,7 +829,7 @@ cleanup() close_tty(); if (pidfilename[0] != 0 && unlink(pidfilename) < 0 && errno != ENOENT) - syslog(LOG_WARNING, "unable to delete pid file: %m"); + warn("unable to delete pid file: %m"); pidfilename[0] = 0; if (locked) @@ -673,8 +845,8 @@ close_tty() disestablish_ppp(ttyfd); /* drop dtr to hang up */ - if (modem) { - setdtr(ttyfd, FALSE); + if (!default_device && modem) { + hangup_modem(ttyfd); /* * This sleep is in case the serial port has CLOCAL set by default, * and consequently will reassert DTR when we close the device. @@ -684,15 +856,31 @@ close_tty() restore_tty(ttyfd); + if (tty_mode != (mode_t) -1) { + if (fchmod(ttyfd, tty_mode) != 0) { + /* XXX if devnam is a symlink, this will change the link */ + chmod(devnam, tty_mode); + } + } + close(ttyfd); ttyfd = -1; } +/* + * hangup_modem - hang up the modem by clearing DTR. + */ +void hangup_modem(ttyfd) + int ttyfd; +{ + setdtr(ttyfd, 0); +} + struct callout { struct timeval c_time; /* time at which to call routine */ - caddr_t c_arg; /* argument to routine */ - void (*c_func)(); /* routine */ + void *c_arg; /* argument to routine */ + void (*c_func) __P((void *)); /* routine */ struct callout *c_next; }; @@ -707,8 +895,8 @@ static struct timeval timenow; /* Current time */ */ void timeout(func, arg, time) - void (*func)(); - caddr_t arg; + void (*func) __P((void *)); + void *arg; int time; { struct callout *newp, *p, **pp; @@ -719,10 +907,8 @@ timeout(func, arg, time) /* * Allocate timeout. */ - if ((newp = (struct callout *) malloc(sizeof(struct callout))) == NULL) { - syslog(LOG_ERR, "Out of memory in timeout()!"); - die(1); - } + 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); @@ -735,7 +921,7 @@ timeout(func, arg, time) 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_sec)) + && newp->c_time.tv_usec < p->c_time.tv_usec)) break; newp->c_next = p; *pp = newp; @@ -747,8 +933,8 @@ timeout(func, arg, time) */ void untimeout(func, arg) - void (*func)(); - caddr_t arg; + void (*func) __P((void *)); + void *arg; { struct callout **copp, *freep; @@ -777,10 +963,8 @@ calltimeout() while (callout != NULL) { p = callout; - if (gettimeofday(&timenow, NULL) < 0) { - syslog(LOG_ERR, "Failed to get time of day: %m"); - die(1); - } + 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))) @@ -816,7 +1000,24 @@ timeleft(tvp) 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. @@ -829,8 +1030,13 @@ static void hup(sig) int sig; { - syslog(LOG_INFO, "Hangup (SIGHUP)"); + info("Hangup (SIGHUP)"); kill_link = 1; + if (conn_running) + /* Send the signal to the [dis]connector process(es) also */ + kill_my_pg(sig); + if (waiting) + siglongjmp(sigjmp, 1); } @@ -844,9 +1050,14 @@ static void term(sig) int sig; { - syslog(LOG_INFO, "Terminating on signal %d.", sig); + info("Terminating on signal %d.", sig); persist = 0; /* don't try to restart */ kill_link = 1; + if (conn_running) + /* Send the signal to the [dis]connector process(es) also */ + kill_my_pg(sig); + if (waiting) + siglongjmp(sigjmp, 1); } @@ -858,7 +1069,8 @@ static void chld(sig) int sig; { - reap_kids(); + if (waiting) + siglongjmp(sigjmp, 1); } @@ -873,7 +1085,11 @@ toggle_debug(sig) int sig; { debug = !debug; - note_debug_level(); + if (debug) { + setlogmask(LOG_UPTO(LOG_DEBUG)); + } else { + setlogmask(LOG_UPTO(LOG_WARNING)); + } } @@ -888,6 +1104,8 @@ open_ccp(sig) int sig; { open_ccp_flag = 1; + if (waiting) + siglongjmp(sigjmp, 1); } @@ -898,7 +1116,14 @@ static void bad_signal(sig) int sig; { - syslog(LOG_ERR, "Fatal signal %d", sig); + static int crashed = 0; + + if (crashed) + _exit(127); + crashed = 1; + error("Fatal signal %d", sig); + if (conn_running) + kill_my_pg(SIGTERM); die(1); } @@ -916,71 +1141,132 @@ device_script(program, in, out) int status; int errfd; + conn_running = 1; pid = fork(); if (pid < 0) { - syslog(LOG_ERR, "Failed to create child process: %m"); - die(1); + conn_running = 0; + fatal("Failed to create child process: %m"); } if (pid == 0) { sys_close(); - dup2(in, 0); - dup2(out, 1); - errfd = open(_PATH_CONNERRS, O_WRONLY | O_APPEND | O_CREAT, 0644); - if (errfd >= 0) - dup2(errfd, 2); - setuid(getuid()); + closelog(); + if (in == out) { + if (in != 0) { + dup2(in, 0); + close(in); + } + dup2(0, 1); + } else { + if (out == 0) + out = dup(out); + if (in != 0) { + dup2(in, 0); + close(in); + } + if (out != 1) { + dup2(out, 1); + close(out); + } + } + if (!nodetach && !updetach) { + close(2); + errfd = open(_PATH_CONNERRS, O_WRONLY | O_APPEND | O_CREAT, 0600); + if (errfd >= 0 && errfd != 2) { + dup2(errfd, 2); + close(errfd); + } + } + setuid(uid); + if (getuid() != uid) { + syslog(LOG_ERR, "setuid failed"); + exit(1); + } setgid(getgid()); execl("/bin/sh", "sh", "-c", program, (char *)0); syslog(LOG_ERR, "could not exec /bin/sh: %m"); - _exit(99); + exit(99); /* NOTREACHED */ } while (waitpid(pid, &status, 0) < 0) { if (errno == EINTR) continue; - syslog(LOG_ERR, "error waiting for (dis)connection process: %m"); - die(1); + fatal("error waiting for (dis)connection process: %m"); } + conn_running = 0; return (status == 0 ? 0 : -1); } +/* + * 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; +}; + +struct subprocess *children; + /* * 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. */ -int -run_program(prog, args, must_exist) +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; - char *nullenv[1]; + struct subprocess *chp; + struct stat sbuf; - pid = fork(); - if (pid == -1) { - syslog(LOG_ERR, "Failed to create child process for %s: %m", prog); - return -1; + /* + * 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) + fatal("Failed to create child process for %s: %m", prog); if (pid == 0) { int new_fd; /* Leave the current location */ - (void) setsid(); /* No controlling tty. */ + (void) setsid(); /* No controlling tty. */ (void) umask (S_IRWXG|S_IRWXO); - (void) chdir ("/"); /* no current directory. */ - setuid(geteuid()); + (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); @@ -1000,21 +1286,35 @@ run_program(prog, args, must_exist) #ifdef BSD /* Force the priority back to zero if pppd is running higher. */ if (setpriority (PRIO_PROCESS, 0, 0) < 0) - syslog (LOG_WARNING, "can't reset priority to 0: %m"); + syslog(LOG_WARNING, "can't reset priority to 0: %m"); #endif /* SysV recommends a second fork at this point. */ - /* run the program; give it a null environment */ - nullenv[0] = NULL; - execve(prog, args, nullenv); + /* run the program */ + execve(prog, args, script_env); if (must_exist || errno != ENOENT) syslog(LOG_WARNING, "Can't execute %s: %m", prog); _exit(-1); } - MAINDEBUG((LOG_DEBUG, "Script %s started; pid = %d", prog, pid)); + + if (debug) + dbglog("Script %s started; pid = %d", prog, pid); ++n_children; - return 0; + + 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; + } + + return pid; } @@ -1026,21 +1326,27 @@ static void reap_kids() { int pid, status; + struct subprocess *chp, **prevp; if (n_children == 0) return; - if ((pid = waitpid(-1, &status, WNOHANG)) == -1) { - if (errno != ECHILD) - syslog(LOG_ERR, "Error waiting for child process: %m"); - return; - } - if (pid > 0) { + while ((pid = waitpid(-1, &status, WNOHANG)) != -1 && pid != 0) { --n_children; + for (prevp = &children; (chp = *prevp) != NULL; prevp = &chp->next) + if (chp->pid == pid) + break; + if (debug) + dbglog("process %d (%s) finished, status = 0x%x", + pid, (chp? chp->prog: "??"), status); if (WIFSIGNALED(status)) { - syslog(LOG_WARNING, "Child process %d terminated with signal %d", - pid, WTERMSIG(status)); + warn("Child process %s (pid %d) terminated with signal %d", + (chp? chp->prog: "??"), pid, WTERMSIG(status)); } + if (chp && chp->done) + (*chp->done)(chp->arg); } + if (pid == -1 && errno != ECHILD) + error("Error waiting for child process: %m"); } @@ -1052,16 +1358,17 @@ char line[256]; /* line to be logged accumulated here */ char *linep; void -log_packet(p, len, prefix) +log_packet(p, len, prefix, level) u_char *p; int len; char *prefix; + int level; { - strcpy(line, prefix); + strlcpy(line, sizeof(line), prefix); linep = line + strlen(line); format_packet(p, len, pr_log, NULL); if (linep != line) - syslog(LOG_DEBUG, "%s", line); + syslog(level, "%s", line); } /* @@ -1098,61 +1405,41 @@ format_packet(p, len, printer, arg) } } - for (; len > 0; --len) { + for (i = 0; i < len && i < 32; ++i) { GETCHAR(x, p); printer(arg, " %.2x", x); } + if (i < len) + printer(arg, " ..."); } -#ifdef __STDC__ -#include - static void -pr_log(void *arg, char *fmt, ...) +pr_log __V((void *arg, char *fmt, ...)) { int n; va_list pvar; char buf[256]; +#if __STDC__ va_start(pvar, fmt); - vsprintf(buf, fmt, pvar); - va_end(pvar); - - n = strlen(buf); - if (linep + n + 1 > line + sizeof(line)) { - syslog(LOG_DEBUG, "%s", line); - linep = line; - } - strcpy(linep, buf); - linep += n; -} - -#else /* __STDC__ */ -#include - -static void -pr_log(arg, fmt, va_alist) -void *arg; -char *fmt; -va_dcl -{ - int n; - va_list pvar; - char buf[256]; - +#else + void *arg; + char *fmt; va_start(pvar); - vsprintf(buf, fmt, pvar); + arg = va_arg(pvar, void *); + fmt = va_arg(pvar, char *); +#endif + + n = vslprintf(buf, sizeof(buf), fmt, pvar); va_end(pvar); - n = strlen(buf); if (linep + n + 1 > line + sizeof(line)) { syslog(LOG_DEBUG, "%s", line); linep = line; } - strcpy(linep, buf); + strlcpy(linep, line + sizeof(line) - linep, buf); linep += n; } -#endif /* * print_string - print a readable representation of a string using @@ -1170,10 +1457,25 @@ print_string(p, len, printer, arg) printer(arg, "\""); for (; len > 0; --len) { c = *p++; - if (' ' <= c && c <= '~') + if (' ' <= c && c <= '~') { + if (c == '\\' || c == '"') + printer(arg, "\\"); printer(arg, "%c", c); - else - printer(arg, "\\%.3o", c); + } else { + switch (c) { + case '\n': + printer(arg, "\\n"); + break; + case '\r': + printer(arg, "\\r"); + break; + case '\t': + printer(arg, "\\t"); + break; + default: + printer(arg, "\\%.3o", c); + } + } } printer(arg, "\""); } @@ -1185,6 +1487,495 @@ void novm(msg) char *msg; { - syslog(LOG_ERR, "Virtual memory exhausted allocating %s\n", msg); - die(1); + fatal("Virtual memory exhausted allocating %s\n", msg); +} + +/* + * slprintf - format a message into a buffer. Like sprintf except we + * also specify the length of the output buffer, and we handle + * %r (recursive format), %m (error message), %v (visible string), + * %q (quoted string), %t (current time) and %I (IP address) formats. + * Doesn't do floating-point formats. + * Returns the number of chars put into buf. + */ +int +slprintf __V((char *buf, int buflen, char *fmt, ...)) +{ + va_list args; + int n; + +#if __STDC__ + va_start(args, fmt); +#else + char *buf; + int buflen; + char *fmt; + va_start(args); + buf = va_arg(args, char *); + buflen = va_arg(args, int); + fmt = va_arg(args, char *); +#endif + n = vslprintf(buf, buflen, fmt, args); + va_end(args); + return n; +} + +/* + * vslprintf - like slprintf, takes a va_list instead of a list of args. + */ +#define OUTCHAR(c) (buflen > 0? (--buflen, *buf++ = (c)): 0) + +int +vslprintf(buf, buflen, fmt, args) + char *buf; + int buflen; + char *fmt; + va_list args; +{ + int c, i, n; + int width, prec, fillch; + int base, len, neg, quoted; + unsigned long val = 0; + char *str, *f, *buf0; + unsigned char *p; + char num[32]; + time_t t; + static char hexchars[] = "0123456789abcdef"; + + buf0 = buf; + --buflen; + while (buflen > 0) { + for (f = fmt; *f != '%' && *f != 0; ++f) + ; + if (f > fmt) { + len = f - fmt; + if (len > buflen) + len = buflen; + memcpy(buf, fmt, len); + buf += len; + buflen -= len; + fmt = f; + } + if (*fmt == 0) + break; + c = *++fmt; + width = prec = 0; + fillch = ' '; + if (c == '0') { + fillch = '0'; + c = *++fmt; + } + if (c == '*') { + width = va_arg(args, int); + c = *++fmt; + } else { + while (isdigit(c)) { + width = width * 10 + c - '0'; + c = *++fmt; + } + } + if (c == '.') { + c = *++fmt; + if (c == '*') { + prec = va_arg(args, int); + c = *++fmt; + } else { + while (isdigit(c)) { + prec = prec * 10 + c - '0'; + c = *++fmt; + } + } + } + str = 0; + base = 0; + neg = 0; + ++fmt; + switch (c) { + case 'd': + i = va_arg(args, int); + if (i < 0) { + neg = 1; + val = -i; + } else + val = i; + base = 10; + break; + case 'o': + val = va_arg(args, unsigned int); + base = 8; + break; + case 'x': + val = va_arg(args, unsigned int); + base = 16; + break; + case 'p': + val = (unsigned long) va_arg(args, void *); + base = 16; + neg = 2; + break; + case 's': + str = va_arg(args, char *); + break; + case 'c': + num[0] = va_arg(args, int); + num[1] = 0; + str = num; + break; + case 'm': + str = strerror(errno); + break; + case 'I': + str = ip_ntoa(va_arg(args, u_int32_t)); + break; + case 'r': + f = va_arg(args, char *); +#ifndef __powerpc__ + n = vslprintf(buf, buflen + 1, f, va_arg(args, va_list)); +#else + /* On the powerpc, a va_list is an array of 1 structure */ + n = vslprintf(buf, buflen + 1, f, va_arg(args, void *)); +#endif + buf += n; + buflen -= n; + continue; + case 't': + time(&t); + str = ctime(&t); + str += 4; /* chop off the day name */ + str[15] = 0; /* chop off year and newline */ + break; + case 'v': /* "visible" string */ + case 'q': /* quoted string */ + quoted = c == 'q'; + p = va_arg(args, unsigned char *); + if (fillch == '0' && prec > 0) { + n = prec; + } else { + n = strlen((char *)p); + if (prec > 0 && prec < n) + n = prec; + } + while (n > 0 && buflen > 0) { + c = *p++; + --n; + if (!quoted && c >= 0x80) { + OUTCHAR('M'); + OUTCHAR('-'); + c -= 0x80; + } + if (quoted && (c == '"' || c == '\\')) + OUTCHAR('\\'); + if (c < 0x20 || (0x7f <= c && c < 0xa0)) { + if (quoted) { + OUTCHAR('\\'); + switch (c) { + case '\t': OUTCHAR('t'); break; + case '\n': OUTCHAR('n'); break; + case '\b': OUTCHAR('b'); break; + case '\f': OUTCHAR('f'); break; + default: + OUTCHAR('x'); + OUTCHAR(hexchars[c >> 4]); + OUTCHAR(hexchars[c & 0xf]); + } + } else { + if (c == '\t') + OUTCHAR(c); + else { + OUTCHAR('^'); + OUTCHAR(c ^ 0x40); + } + } + } else + OUTCHAR(c); + } + continue; + default: + *buf++ = '%'; + if (c != '%') + --fmt; /* so %z outputs %z etc. */ + --buflen; + continue; + } + if (base != 0) { + str = num + sizeof(num); + *--str = 0; + while (str > num + neg) { + *--str = hexchars[val % base]; + val = val / base; + if (--prec <= 0 && val == 0) + break; + } + switch (neg) { + case 1: + *--str = '-'; + break; + case 2: + *--str = 'x'; + *--str = '0'; + break; + } + len = num + sizeof(num) - 1 - str; + } else { + len = strlen(str); + if (prec > 0 && len > prec) + len = prec; + } + if (width > 0) { + if (width > buflen) + width = buflen; + if ((n = width - len) > 0) { + buflen -= n; + for (; n > 0; --n) + *buf++ = fillch; + } + } + if (len > buflen) + len = buflen; + memcpy(buf, str, len); + buf += len; + buflen -= len; + } + *buf = 0; + return buf - buf0; +} + +/* + * 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) + char *var, *value; +{ + size_t vl = strlen(var) + strlen(value) + 2; + int i; + char *p, *newstring; + + newstring = (char *) malloc(vl); + if (newstring == 0) + return; + 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, vl) == 0 && p[vl] == '=') { + free(p); + script_env[i] = newstring; + return; + } + } + } else { + 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; +} + +/* + * 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] == '=') { + free(p); + while ((script_env[i] = script_env[i+1]) != 0) + ++i; + break; + } + } +} + +/* + * strlcpy - like strcpy/strncpy, doesn't overflow destination buffer, + * always leaves destination null-terminated (for len > 0). + */ +void +strlcpy(char *dest, size_t len, const char *src) +{ + if (len == 0) + return; + if (strlen(src) < len) + strcpy(dest, src); + else { + strncpy(dest, src, len - 1); + dest[len-1] = 0; + } +} + +/* + * strlcat - like strcat/strncat, doesn't overflow destination buffer, + * always leaves destination null-terminated (for len > 0). + */ +void +strlcat(char *dest, size_t len, const char *src) +{ + size_t dlen; + + if (len == 0) + return; + dlen = strlen(dest); + if (dlen < len - 1) + strlcpy(dest + dlen, len - dlen, src); +} + +/* + * fatal - log an error message and die horribly. + */ +void +fatal __V((char *fmt, ...)) +{ + va_list pvar; + +#if __STDC__ + va_start(pvar, fmt); +#else + char *fmt; + va_start(pvar); + fmt = va_arg(pvar, char *); +#endif + + vslprintf(line, sizeof(line), fmt, pvar); + va_end(pvar); + + syslog(LOG_ERR, "%s", line); + + die(1); /* as promised */ +} + +/* + * error - log an error message. + */ +void +error __V((char *fmt, ...)) +{ + va_list pvar; + +#if __STDC__ + va_start(pvar, fmt); +#else + char *fmt; + va_start(pvar); + fmt = va_arg(pvar, char *); +#endif + + vslprintf(line, sizeof(line), fmt, pvar); + va_end(pvar); + + syslog(LOG_ERR, "%s", line); +} + +/* + * warn - log a warning message. + */ +void +warn __V((char *fmt, ...)) +{ + va_list pvar; + +#if __STDC__ + va_start(pvar, fmt); +#else + char *fmt; + va_start(pvar); + fmt = va_arg(pvar, char *); +#endif + + vslprintf(line, sizeof(line), fmt, pvar); + va_end(pvar); + + syslog(LOG_WARNING, "%s", line); +} + +/* + * notice - log a notice-level message. + */ +void +notice __V((char *fmt, ...)) +{ + va_list pvar; + +#if __STDC__ + va_start(pvar, fmt); +#else + char *fmt; + va_start(pvar); + fmt = va_arg(pvar, char *); +#endif + + vslprintf(line, sizeof(line), fmt, pvar); + va_end(pvar); + + syslog(LOG_NOTICE, "%s", line); +} + +/* + * info - log an informational message. + */ +void +info __V((char *fmt, ...)) +{ + va_list pvar; + +#if __STDC__ + va_start(pvar, fmt); +#else + char *fmt; + va_start(pvar); + fmt = va_arg(pvar, char *); +#endif + + vslprintf(line, sizeof(line), fmt, pvar); + va_end(pvar); + + syslog(LOG_INFO, "%s", line); +} + +/* + * dbglog - log a debug message. + */ +void +dbglog __V((char *fmt, ...)) +{ + va_list pvar; + +#if __STDC__ + va_start(pvar, fmt); +#else + char *fmt; + va_start(pvar); + fmt = va_arg(pvar, char *); +#endif + + vslprintf(line, sizeof(line), fmt, pvar); + va_end(pvar); + + syslog(LOG_DEBUG, "%s", line); }