/*
* demand_block - set each network protocol to block further packets.
*/
void
demand_block(void)
{
int i;
struct protent *protp;
for (i = 0; (protp = protocols[i]) != NULL; ++i)
if (protp->enabled_flag && protp->demand_conf != NULL)
sifnpmode(0, protp->protocol & ~0x8000, NPMODE_QUEUE);
get_loop_output();
}
/*
* demand_block - set each network protocol to block further packets.
*/
void
demand_block()
{
int i;
const struct protent *protp;
for (i = 0; (protp = protocols[i]) != NULL; ++i)
if (protp->demand_conf != NULL)
sifnpmode(pcb, protp->protocol & ~0x8000, NPMODE_QUEUE);
get_loop_output();
}
/*
* demand_discard - set each network protocol to discard packets
* with an error.
*/
void
demand_discard(void)
{
struct packet *pkt, *nextpkt;
int i;
struct protent *protp;
for (i = 0; (protp = protocols[i]) != NULL; ++i)
if (protp->enabled_flag && protp->demand_conf != NULL)
sifnpmode(0, protp->protocol & ~0x8000, NPMODE_ERROR);
get_loop_output();
/* discard all saved packets */
for (pkt = pend_q; pkt != NULL; pkt = nextpkt) {
nextpkt = pkt->next;
free(pkt);
}
pend_q = NULL;
framelen = 0;
flush_flag = 0;
escape_flag = 0;
fcs = PPP_INITFCS;
}
int
main(int argc, char *argv[])
{
int i, n, fdflags;
struct sigaction sa;
FILE *iffile;
char *p;
struct passwd *pw;
struct timeval timo;
sigset_t mask;
struct protent *protp;
struct stat statbuf;
int connect_attempts = 0;
char numbuf[16];
phase = PHASE_INITIALIZE;
p = ttyname(0);
if (p)
strcpy(devnam, p);
strcpy(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 ) {
option_error("Couldn't get hostname: %m");
die(1);
}
hostname[MAXNAMELEN-1] = 0;
uid = getuid();
privileged = uid == 0;
sprintf(numbuf, "%d", uid);
script_setenv("UID", numbuf);
/*
* Initialize to the standard option set, then parse, in order,
* 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, !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]);
die(1);
}
if (!ppp_available()) {
option_error(no_ppp_msg);
exit(1);
}
/*
* Check that the options given are valid and consistent.
*/
sys_check_options();
auth_check_options();
for (i = 0; (protp = protocols[i]) != NULL; ++i)
if (protp->check_options != NULL)
(*protp->check_options)();
if (demand && connector == 0) {
option_error("connect script 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 (nodetach == 0)
detach();
pid = getpid();
p = getlogin();
stime = time(NULL);
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.%d%s started by %s, uid %d",
VERSION, PATCHLEVEL, IMPLEMENTATION, p, uid);
/*
* 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);
#define SIGNAL(s, handler) { \
sa.sa_handler = handler; \
if (sigaction(s, &sa, NULL) < 0) { \
syslog(LOG_ERR, "Couldn't establish signal handler (%d): %m", s); \
die(1); \
} \
}
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);
/*
* 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.
*/
open_ppp_loopback();
syslog(LOG_INFO, "Using interface ppp%d", ifunit);
sprintf(ifname, "ppp%d", ifunit);
script_setenv("IFNAME", ifname);
create_pidfile(); /* write pid to file */
/*
* Configure the interface and mark it up, etc.
*/
demand_conf();
}
for (;;) {
need_holdoff = 1;
if (demand) {
/*
* Don't do anything until we see some activity.
*/
phase = PHASE_DORMANT;
kill_link = 0;
demand_unblock();
for (;;) {
wait_loop_output(timeleft(&timo));
calltimeout();
if (kill_link) {
if (!persist)
die(0);
kill_link = 0;
}
if (get_loop_output())
break;
reap_kids();
}
/*
* Now we want to bring up the link.
*/
demand_block();
syslog(LOG_INFO, "Starting link");
}
/*
* Lock the device if we've been asked to.
*/
if (lockflag && !default_device) {
if (lock(devnam) < 0)
goto fail;
locked = 1;
}
/*
* Open the serial device and set it up to be the ppp interface.
* 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.
*/
while ((ttyfd = open(devnam, O_NONBLOCK | O_RDWR, 0)) < 0) {
if (errno != EINTR)
syslog(LOG_ERR, "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)
syslog(LOG_WARNING,
"Couldn't reset non-blocking mode on device: %m");
hungup = 0;
kill_link = 0;
/*
* 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) {
syslog(LOG_WARNING,
"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.
* 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 can clear CLOCAL at this point.
*/
set_up_tty(ttyfd, 1);
/* drop dtr to hang up in case modem is off hook */
if (!default_device && modem) {
setdtr(ttyfd, FALSE);
sleep(1);
setdtr(ttyfd, TRUE);
}
if (device_script(connector, ttyfd, ttyfd) < 0) {
syslog(LOG_ERR, "Connect script failed");
setdtr(ttyfd, FALSE);
connect_attempts++;
goto fail;
}
syslog(LOG_INFO, "Serial connection established.");
sleep(1); /* give it time to set up its terminal */
}
connect_attempts = 0; /* we made it through ok */
/* 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) {
while ((i = open(devnam, O_RDWR)) < 0) {
if (errno != EINTR)
syslog(LOG_ERR, "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");
}
/* set up the serial device as a ppp interface */
establish_ppp(ttyfd);
if (!demand) {
syslog(LOG_INFO, "Using interface ppp%d", ifunit);
sprintf(ifname, "ppp%d", ifunit);
create_pidfile(); /* write pid to file */
/* write interface unit number to file */
for (n = strlen(devnam); n > 0 ; n--)
if (devnam[n] == '/') {
n++;
break;
}
sprintf(iffilename, "%s%s.if", _PATH_VARRUN, &devnam[n]);
if ((iffile = fopen(iffilename, "w")) != NULL) {
fprintf(iffile, "ppp%d\n", ifunit);
fclose(iffile);
} else {
syslog(LOG_ERR, "Failed to create if file %s: %m", iffilename);
iffilename[0] = 0;
}
script_setenv("IFNAME", ifname);
}
/*
* Start opening the connection and wait for
* incoming events (reply, timeout, etc.).
*/
syslog(LOG_NOTICE, "Connect: %s <--> %s", ifname, devnam);
stime = time(NULL);
lcp_lowerup(0);
lcp_open(0); /* Start protocol */
for (phase = PHASE_ESTABLISH; phase != PHASE_DEAD; ) {
wait_input(timeleft(&timo));
calltimeout();
get_input();
if (kill_link) {
lcp_close(0, "User request");
kill_link = 0;
}
if (open_ccp_flag) {
if (phase == PHASE_NETWORK) {
ccp_fsm[0].flags = OPT_RESTART; /* clears OPT_SILENT */
(*ccp_protent.open)(0);
}
open_ccp_flag = 0;
}
reap_kids(); /* Don't leave dead kids lying around */
}
/*
* 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.
*/
clean_check();
if (demand)
restore_loop();
disestablish_ppp(ttyfd);
/*
* Run disconnector script, if requested.
* XXX we may not be able to do this if the line has hung up!
*/
if (disconnector && !hungup) {
set_up_tty(ttyfd, 1);
if (device_script(disconnector, ttyfd, ttyfd) < 0) {
syslog(LOG_WARNING, "disconnect script failed");
} else {
syslog(LOG_INFO, "Serial link disconnected.");
}
}
fail:
if (ttyfd >= 0)
close_tty();
if (locked) {
unlock();
locked = 0;
}
if (!demand) {
if (pidfilename[0] != 0
&& unlink(pidfilename) < 0 && errno != ENOENT)
syslog(LOG_WARNING, "unable to delete pid file: %m");
pidfilename[0] = 0;
if (iffile)
if (unlink(iffilename) < 0 && errno != ENOENT)
syslog(LOG_WARNING, "unable to delete if file: %m");
iffilename[0] = 0;
}
/* limit to retries? */
if (max_con_attempts)
if (connect_attempts >= max_con_attempts)
break;
if (!persist)
die(1);
if (demand)
demand_discard();
if (holdoff > 0 && need_holdoff) {
phase = PHASE_HOLDOFF;
TIMEOUT(holdoff_end, NULL, holdoff);
do {
wait_time(timeleft(&timo));
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);
}
}
die(0);
return 0;
}
