freebsd-nq/usr.sbin/ppp/main.c
Brian Somers 683cef3c33 Install as group ``network''
Insist that uid == 0 for client ppp
Disallow client sockets if no password is specified
Don't exit on failure to open client socket for listening
Allow specification of null local password
Use reasonable size (smaller) ``vector''s in auth.c
Fix "passwd ..." usage message
Insist on "all" as arg to "quit" (if any)
Drop client socket connection before Cleanup() when "quit all"
1997-09-04 00:38:22 +00:00

1029 lines
24 KiB
C

/*
* User Process PPP
*
* Written by Toshiharu OHNO (tony-o@iij.ad.jp)
*
* Copyright (C) 1993, Internet Initiative Japan, Inc. All rights reserverd.
*
* Redistribution and use in source and binary forms are permitted
* provided that the above copyright notice and this paragraph are
* duplicated in all such forms and that any documentation,
* advertising materials, and other materials related to such
* distribution and use acknowledge that the software was developed
* by the Internet Initiative Japan, Inc. The name of the
* IIJ may not be used to endorse or promote products derived
* from this software without specific prior written permission.
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
* WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*
* $Id: main.c,v 1.76 1997/08/31 22:59:39 brian Exp $
*
* TODO:
* o Add commands for traffic summary, version display, etc.
* o Add signal handler for misc controls.
*/
#include "fsm.h"
#include <fcntl.h>
#include <paths.h>
#include <sys/time.h>
#include <termios.h>
#include <signal.h>
#include <sys/wait.h>
#include <errno.h>
#include <netdb.h>
#include <unistd.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <sysexits.h>
#include "modem.h"
#include "os.h"
#include "hdlc.h"
#include "ccp.h"
#include "lcp.h"
#include "ipcp.h"
#include "loadalias.h"
#include "vars.h"
#include "auth.h"
#include "filter.h"
#include "systems.h"
#include "ip.h"
#include "sig.h"
#include "server.h"
#include "lcpproto.h"
#ifndef O_NONBLOCK
#ifdef O_NDELAY
#define O_NONBLOCK O_NDELAY
#endif
#endif
extern void VjInit(), AsyncInit();
extern void AsyncInput();
extern int SelectSystem();
extern void DecodeCommand(), Prompt();
extern int aft_cmd;
extern int IsInteractive();
static void DoLoop(void);
static void TerminalStop();
static char *ex_desc();
static struct termios oldtio; /* Original tty mode */
static struct termios comtio; /* Command level tty mode */
int TermMode;
static pid_t BGPid = 0;
static char pid_filename[MAXPATHLEN];
static char if_filename[MAXPATHLEN];
int tunno;
static int dial_up;
static void
TtyInit(int DontWantInt)
{
struct termios newtio;
int stat;
stat = fcntl(0, F_GETFL, 0);
if (stat > 0) {
stat |= O_NONBLOCK;
(void) fcntl(0, F_SETFL, stat);
}
newtio = oldtio;
newtio.c_lflag &= ~(ECHO | ISIG | ICANON);
newtio.c_iflag = 0;
newtio.c_oflag &= ~OPOST;
newtio.c_cc[VEOF] = _POSIX_VDISABLE;
if (DontWantInt)
newtio.c_cc[VINTR] = _POSIX_VDISABLE;
newtio.c_cc[VMIN] = 1;
newtio.c_cc[VTIME] = 0;
newtio.c_cflag |= CS8;
tcsetattr(0, TCSADRAIN, &newtio);
comtio = newtio;
}
/*
* Set tty into command mode. We allow canonical input and echo processing.
*/
void
TtyCommandMode(int prompt)
{
struct termios newtio;
int stat;
if (!(mode & MODE_INTER))
return;
tcgetattr(0, &newtio);
newtio.c_lflag |= (ECHO | ISIG | ICANON);
newtio.c_iflag = oldtio.c_iflag;
newtio.c_oflag |= OPOST;
tcsetattr(0, TCSADRAIN, &newtio);
stat = fcntl(0, F_GETFL, 0);
if (stat > 0) {
stat |= O_NONBLOCK;
(void) fcntl(0, F_SETFL, stat);
}
TermMode = 0;
if (prompt)
Prompt();
}
/*
* Set tty into terminal mode which is used while we invoke term command.
*/
void
TtyTermMode()
{
int stat;
tcsetattr(0, TCSADRAIN, &comtio);
stat = fcntl(0, F_GETFL, 0);
if (stat > 0) {
stat &= ~O_NONBLOCK;
(void) fcntl(0, F_SETFL, stat);
}
TermMode = 1;
}
void
TtyOldMode()
{
int stat;
stat = fcntl(0, F_GETFL, 0);
if (stat > 0) {
stat &= ~O_NONBLOCK;
(void) fcntl(0, F_SETFL, stat);
}
tcsetattr(0, TCSANOW, &oldtio);
}
void
Cleanup(int excode)
{
OsLinkdown();
OsCloseLink(1);
sleep(1);
if (mode & MODE_AUTO)
DeleteIfRoutes(1);
(void) unlink(pid_filename);
(void) unlink(if_filename);
OsInterfaceDown(1);
if (mode & MODE_BACKGROUND && BGFiledes[1] != -1) {
char c = EX_ERRDEAD;
if (write(BGFiledes[1], &c, 1) == 1)
LogPrintf(LogPHASE, "Parent notified of failure.\n");
else
LogPrintf(LogPHASE, "Failed to notify parent of failure.\n");
close(BGFiledes[1]);
}
LogPrintf(LogPHASE, "PPP Terminated (%s).\n", ex_desc(excode));
LogClose();
ServerClose();
TtyOldMode();
exit(excode);
}
static void
CloseConnection(int signo)
{
/* NOTE, these are manual, we've done a setsid() */
LogPrintf(LogPHASE, "Caught signal %d, abort connection\n", signo);
reconnectState = RECON_FALSE;
reconnectCount = 0;
DownConnection();
dial_up = FALSE;
}
static void
CloseSession(int signo)
{
if (BGPid) {
kill(BGPid, SIGINT);
exit(EX_TERM);
}
LogPrintf(LogPHASE, "Signal %d, terminate.\n", signo);
reconnect(RECON_FALSE);
LcpClose();
Cleanup(EX_TERM);
}
static void
TerminalCont()
{
pending_signal(SIGCONT, SIG_DFL);
pending_signal(SIGTSTP, TerminalStop);
TtyCommandMode(getpgrp() == tcgetpgrp(0));
}
static void
TerminalStop(int signo)
{
pending_signal(SIGCONT, TerminalCont);
TtyOldMode();
pending_signal(SIGTSTP, SIG_DFL);
kill(getpid(), signo);
}
static void
SetUpServer(int signo)
{
int res;
if ((res = ServerTcpOpen(SERVER_PORT + tunno)) != 0)
LogPrintf(LogERROR, "SIGUSR1: Failed %d to open port %d\n",
res, SERVER_PORT + tunno);
}
static char *
ex_desc(int ex)
{
static char num[12];
static char *desc[] = {"normal", "start", "sock",
"modem", "dial", "dead", "done", "reboot", "errdead",
"hangup", "term", "nodial", "nologin"};
if (ex >= 0 && ex < sizeof(desc) / sizeof(*desc))
return desc[ex];
snprintf(num, sizeof num, "%d", ex);
return num;
}
void
Usage()
{
fprintf(stderr,
"Usage: ppp [-auto | -background | -direct | -dedicated | -ddial ] [ -alias ] [system]\n");
exit(EX_START);
}
void
ProcessArgs(int argc, char **argv)
{
int optc;
char *cp;
optc = 0;
while (argc > 0 && **argv == '-') {
cp = *argv + 1;
if (strcmp(cp, "auto") == 0)
mode |= MODE_AUTO;
else if (strcmp(cp, "background") == 0)
mode |= MODE_BACKGROUND | MODE_AUTO;
else if (strcmp(cp, "direct") == 0)
mode |= MODE_DIRECT;
else if (strcmp(cp, "dedicated") == 0)
mode |= MODE_DEDICATED;
else if (strcmp(cp, "ddial") == 0)
mode |= MODE_DDIAL | MODE_AUTO;
else if (strcmp(cp, "alias") == 0) {
if (loadAliasHandlers(&VarAliasHandlers) == 0)
mode |= MODE_ALIAS;
else
LogPrintf(LogWARN, "Cannot load alias library\n");
optc--; /* this option isn't exclusive */
} else
Usage();
optc++;
argv++;
argc--;
}
if (argc > 1) {
fprintf(stderr, "specify only one system label.\n");
exit(EX_START);
}
if (argc == 1)
dstsystem = *argv;
if (optc > 1) {
fprintf(stderr, "specify only one mode.\n");
exit(EX_START);
}
}
static void
Greetings()
{
if (VarTerm) {
fprintf(VarTerm, "User Process PPP. Written by Toshiharu OHNO.\n");
fflush(VarTerm);
}
}
int
main(int argc, char **argv)
{
FILE *lockfile;
char *name;
VarTerm = 0;
name = rindex(argv[0], '/');
LogOpen(name ? name + 1 : argv[0]);
argc--;
argv++;
mode = MODE_INTER; /* default operation is interactive mode */
netfd = modem = tun_in = -1;
server = -2;
ProcessArgs(argc, argv);
if (!(mode & MODE_DIRECT)) {
if (getuid() != 0) {
fprintf(stderr, "You may only run ppp in client mode as user id 0\n");
LogClose();
return EX_NOPERM;
}
VarTerm = stdout;
}
Greetings();
GetUid();
IpcpDefAddress();
LocalAuthInit();
if (SelectSystem("default", CONFFILE) < 0 && VarTerm)
fprintf(VarTerm, "Warning: No default entry is given in config file.\n");
if (OpenTunnel(&tunno) < 0) {
LogPrintf(LogWARN, "open_tun: %s\n", strerror(errno));
return EX_START;
}
if (mode & (MODE_AUTO | MODE_DIRECT | MODE_DEDICATED))
mode &= ~MODE_INTER;
if (mode & MODE_INTER) {
fprintf(VarTerm, "Interactive mode\n");
netfd = STDOUT_FILENO;
} else if (mode & MODE_AUTO) {
fprintf(VarTerm, "Automatic Dialer mode\n");
if (dstsystem == NULL) {
if (VarTerm)
fprintf(VarTerm, "Destination system must be specified in"
" auto, background or ddial mode.\n");
return EX_START;
}
}
tcgetattr(0, &oldtio); /* Save original tty mode */
pending_signal(SIGHUP, CloseSession);
pending_signal(SIGTERM, CloseSession);
pending_signal(SIGINT, CloseConnection);
pending_signal(SIGQUIT, CloseSession);
#ifdef SIGPIPE
signal(SIGPIPE, SIG_IGN);
#endif
#ifdef SIGALRM
pending_signal(SIGALRM, SIG_IGN);
#endif
if (mode & MODE_INTER) {
#ifdef SIGTSTP
pending_signal(SIGTSTP, TerminalStop);
#endif
#ifdef SIGTTIN
pending_signal(SIGTTIN, TerminalStop);
#endif
#ifdef SIGTTOU
pending_signal(SIGTTOU, SIG_IGN);
#endif
}
#ifdef SIGUSR1
if (mode != MODE_INTER)
pending_signal(SIGUSR1, SetUpServer);
#endif
if (dstsystem) {
if (SelectSystem(dstsystem, CONFFILE) < 0) {
LogPrintf(LogWARN, "Destination system not found in conf file.\n");
Cleanup(EX_START);
}
if ((mode & MODE_AUTO) && DefHisAddress.ipaddr.s_addr == INADDR_ANY) {
LogPrintf(LogWARN, "Must specify dstaddr with"
" auto, background or ddial mode.\n");
Cleanup(EX_START);
}
}
if (!(mode & MODE_INTER)) {
if (mode & MODE_BACKGROUND) {
if (pipe(BGFiledes)) {
LogPrintf(LogERROR, "pipe: %s\n", strerror(errno));
Cleanup(EX_SOCK);
}
}
/* Create server socket and listen. */
if (server == -2)
ServerTcpOpen(SERVER_PORT + tunno);
if (!(mode & MODE_DIRECT)) {
pid_t bgpid;
bgpid = fork();
if (bgpid == -1) {
LogPrintf(LogERROR, "fork: %s\n", strerror(errno));
Cleanup(EX_SOCK);
}
if (bgpid) {
char c = EX_NORMAL;
if (mode & MODE_BACKGROUND) {
/* Wait for our child to close its pipe before we exit. */
BGPid = bgpid;
close(BGFiledes[1]);
if (read(BGFiledes[0], &c, 1) != 1) {
fprintf(VarTerm, "Child exit, no status.\n");
LogPrintf(LogPHASE, "Parent: Child exit, no status.\n");
} else if (c == EX_NORMAL) {
fprintf(VarTerm, "PPP enabled.\n");
LogPrintf(LogPHASE, "Parent: PPP enabled.\n");
} else {
fprintf(VarTerm, "Child failed (%s).\n", ex_desc((int) c));
LogPrintf(LogPHASE, "Parent: Child failed (%s).\n",
ex_desc((int) c));
}
close(BGFiledes[0]);
}
return c;
} else if (mode & MODE_BACKGROUND)
close(BGFiledes[0]);
}
snprintf(pid_filename, sizeof(pid_filename), "%stun%d.pid",
_PATH_VARRUN, tunno);
(void) unlink(pid_filename);
if ((lockfile = fopen(pid_filename, "w")) != NULL) {
fprintf(lockfile, "%d\n", (int) getpid());
fclose(lockfile);
} else
LogPrintf(LogALERT, "Warning: Can't create %s: %s\n",
pid_filename, strerror(errno));
snprintf(if_filename, sizeof if_filename, "%s%s.if",
_PATH_VARRUN, VarBaseDevice);
(void) unlink(if_filename);
if ((lockfile = fopen(if_filename, "w")) != NULL) {
fprintf(lockfile, "tun%d\n", tunno);
fclose(lockfile);
} else
LogPrintf(LogALERT, "Warning: Can't create %s: %s\n",
if_filename, strerror(errno));
VarTerm = 0; /* We know it's currently stdout */
close(0);
close(2);
#ifdef DOTTYINIT
if (mode & (MODE_DIRECT | MODE_DEDICATED))
#else
if (mode & MODE_DIRECT)
#endif
TtyInit(1);
else {
setsid();
close(1);
}
} else {
TtyInit(0);
TtyCommandMode(1);
}
LogPrintf(LogPHASE, "PPP Started.\n");
do
DoLoop();
while (mode & MODE_DEDICATED);
Cleanup(EX_DONE);
return 0;
}
/*
* Turn into packet mode, where we speak PPP.
*/
void
PacketMode()
{
if (RawModem(modem) < 0) {
LogPrintf(LogWARN, "PacketMode: Not connected.\n");
return;
}
AsyncInit();
VjInit();
LcpInit();
IpcpInit();
CcpInit();
LcpUp();
LcpOpen(VarOpenMode);
if ((mode & (MODE_INTER | MODE_AUTO)) == MODE_INTER) {
TtyCommandMode(1);
if (VarTerm) {
fprintf(VarTerm, "Packet mode.\n");
aft_cmd = 1;
}
}
}
static void
ShowHelp()
{
fprintf(stderr, "The following commands are available:\r\n");
fprintf(stderr, " ~p\tEnter Packet mode\r\n");
fprintf(stderr, " ~-\tDecrease log level\r\n");
fprintf(stderr, " ~+\tIncrease log level\r\n");
fprintf(stderr, " ~t\tShow timers (only in \"log debug\" mode)\r\n");
fprintf(stderr, " ~m\tShow memory map (only in \"log debug\" mode)\r\n");
fprintf(stderr, " ~.\tTerminate program\r\n");
fprintf(stderr, " ~?\tThis help\r\n");
}
static void
ReadTty()
{
int n;
char ch;
static int ttystate;
FILE *oVarTerm;
#define MAXLINESIZE 200
char linebuff[MAXLINESIZE];
LogPrintf(LogDEBUG, "termode = %d, netfd = %d, mode = %d\n",
TermMode, netfd, mode);
if (!TermMode) {
n = read(netfd, linebuff, sizeof(linebuff) - 1);
if (n > 0) {
aft_cmd = 1;
DecodeCommand(linebuff, n, 1);
} else {
LogPrintf(LogPHASE, "client connection closed.\n");
VarLocalAuth = LOCAL_NO_AUTH;
mode &= ~MODE_INTER;
oVarTerm = VarTerm;
VarTerm = 0;
if (oVarTerm && oVarTerm != stdout)
fclose(oVarTerm);
close(netfd);
netfd = -1;
}
return;
}
/*
* We are in terminal mode, decode special sequences
*/
n = read(fileno(VarTerm), &ch, 1);
LogPrintf(LogDEBUG, "Got %d bytes (reading from the terminal)\n", n);
if (n > 0) {
switch (ttystate) {
case 0:
if (ch == '~')
ttystate++;
else
write(modem, &ch, n);
break;
case 1:
switch (ch) {
case '?':
ShowHelp();
break;
case 'p':
/*
* XXX: Should check carrier.
*/
if (LcpFsm.state <= ST_CLOSED) {
VarOpenMode = OPEN_ACTIVE;
PacketMode();
}
break;
case '.':
TermMode = 1;
aft_cmd = 1;
TtyCommandMode(1);
break;
case 't':
if (LogIsKept(LogDEBUG)) {
ShowTimers();
break;
}
case 'm':
if (LogIsKept(LogDEBUG)) {
ShowMemMap();
break;
}
default:
if (write(modem, &ch, n) < 0)
LogPrintf(LogERROR, "error writing to modem.\n");
break;
}
ttystate = 0;
break;
}
}
}
/*
* Here, we'll try to detect HDLC frame
*/
static char *FrameHeaders[] = {
"\176\377\003\300\041",
"\176\377\175\043\300\041",
"\176\177\175\043\100\041",
"\176\175\337\175\043\300\041",
"\176\175\137\175\043\100\041",
NULL,
};
u_char *
HdlcDetect(u_char * cp, int n)
{
char *ptr, *fp, **hp;
cp[n] = '\0'; /* be sure to null terminated */
ptr = NULL;
for (hp = FrameHeaders; *hp; hp++) {
fp = *hp;
if (DEV_IS_SYNC)
fp++;
ptr = strstr((char *) cp, fp);
if (ptr)
break;
}
return ((u_char *) ptr);
}
static struct pppTimer RedialTimer;
static void
RedialTimeout()
{
StopTimer(&RedialTimer);
LogPrintf(LogPHASE, "Redialing timer expired.\n");
}
static void
StartRedialTimer(int Timeout)
{
StopTimer(&RedialTimer);
if (Timeout) {
RedialTimer.state = TIMER_STOPPED;
if (Timeout > 0)
RedialTimer.load = Timeout * SECTICKS;
else
RedialTimer.load = (random() % REDIAL_PERIOD) * SECTICKS;
LogPrintf(LogPHASE, "Enter pause (%d) for redialing.\n",
RedialTimer.load / SECTICKS);
RedialTimer.func = RedialTimeout;
StartTimer(&RedialTimer);
}
}
static void
DoLoop()
{
fd_set rfds, wfds, efds;
int pri, i, n, wfd, nfds;
struct sockaddr_in hisaddr;
struct timeval timeout, *tp;
int ssize = sizeof(hisaddr);
u_char *cp;
u_char rbuff[MAX_MRU];
int tries;
int qlen;
int res;
pid_t pgroup;
pgroup = getpgrp();
if (mode & MODE_DIRECT) {
LogPrintf(LogDEBUG, "Opening modem\n");
modem = OpenModem(mode);
LogPrintf(LogPHASE, "Packet mode enabled\n");
PacketMode();
} else if (mode & MODE_DEDICATED) {
if (modem < 0)
modem = OpenModem(mode);
}
fflush(VarTerm);
timeout.tv_sec = 0;
timeout.tv_usec = 0;
reconnectState = RECON_UNKNOWN;
if (mode & MODE_BACKGROUND)
dial_up = TRUE; /* Bring the line up */
else
dial_up = FALSE; /* XXXX */
tries = 0;
for (;;) {
nfds = 0;
FD_ZERO(&rfds);
FD_ZERO(&wfds);
FD_ZERO(&efds);
/*
* If the link is down and we're in DDIAL mode, bring it back up.
*/
if (mode & MODE_DDIAL && LcpFsm.state <= ST_CLOSED)
dial_up = TRUE;
/*
* If we lost carrier and want to re-establish the connection due to the
* "set reconnect" value, we'd better bring the line back up.
*/
if (LcpFsm.state <= ST_CLOSED) {
if (dial_up != TRUE && reconnectState == RECON_TRUE) {
if (++reconnectCount <= VarReconnectTries) {
LogPrintf(LogPHASE, "Connection lost, re-establish (%d/%d)\n",
reconnectCount, VarReconnectTries);
StartRedialTimer(VarReconnectTimer);
dial_up = TRUE;
} else {
if (VarReconnectTries)
LogPrintf(LogPHASE, "Connection lost, maximum (%d) times\n",
VarReconnectTries);
reconnectCount = 0;
if (mode & MODE_BACKGROUND)
Cleanup(EX_DEAD);
}
reconnectState = RECON_ENVOKED;
}
}
/*
* If Ip packet for output is enqueued and require dial up, Just do it!
*/
if (dial_up && RedialTimer.state != TIMER_RUNNING) {
LogPrintf(LogDEBUG, "going to dial: modem = %d\n", modem);
modem = OpenModem(mode);
if (modem < 0) {
tries++;
if (!(mode & MODE_DDIAL) && VarDialTries)
LogPrintf(LogCHAT, "Failed to open modem (attempt %u of %d)\n",
tries, VarDialTries);
else
LogPrintf(LogCHAT, "Failed to open modem (attempt %u)\n", tries);
if (!(mode & MODE_DDIAL) && VarDialTries && tries >= VarDialTries) {
if (mode & MODE_BACKGROUND)
Cleanup(EX_DIAL); /* Can't get the modem */
dial_up = FALSE;
reconnectState = RECON_UNKNOWN;
reconnectCount = 0;
tries = 0;
} else
StartRedialTimer(VarRedialTimeout);
} else {
tries++; /* Tries are per number, not per list of
* numbers. */
if (!(mode & MODE_DDIAL) && VarDialTries)
LogPrintf(LogCHAT, "Dial attempt %u of %d\n", tries, VarDialTries);
else
LogPrintf(LogCHAT, "Dial attempt %u\n", tries);
if ((res = DialModem()) == EX_DONE) {
sleep(1); /* little pause to allow peer starts */
ModemTimeout();
PacketMode();
dial_up = FALSE;
reconnectState = RECON_UNKNOWN;
tries = 0;
} else {
CloseModem();
if (mode & MODE_BACKGROUND) {
if (VarNextPhone == NULL || res == EX_SIG)
Cleanup(EX_DIAL); /* Tried all numbers - no luck */
else
/* Try all numbers in background mode */
StartRedialTimer(VarRedialNextTimeout);
} else if (!(mode & MODE_DDIAL) &&
((VarDialTries && tries >= VarDialTries) ||
res == EX_SIG)) {
/* I give up ! Can't get through :( */
StartRedialTimer(VarRedialTimeout);
dial_up = FALSE;
reconnectState = RECON_UNKNOWN;
reconnectCount = 0;
tries = 0;
} else if (VarNextPhone == NULL)
/* Dial failed. Keep quite during redial wait period. */
StartRedialTimer(VarRedialTimeout);
else
StartRedialTimer(VarRedialNextTimeout);
}
}
}
qlen = ModemQlen();
if (qlen == 0) {
IpStartOutput();
qlen = ModemQlen();
}
if (modem >= 0) {
if (modem + 1 > nfds)
nfds = modem + 1;
FD_SET(modem, &rfds);
FD_SET(modem, &efds);
if (qlen > 0) {
FD_SET(modem, &wfds);
}
}
if (server >= 0) {
if (server + 1 > nfds)
nfds = server + 1;
FD_SET(server, &rfds);
}
/*
* *** IMPORTANT ***
*
* CPU is serviced every TICKUNIT micro seconds. This value must be chosen
* with great care. If this values is too big, it results loss of
* characters from modem and poor responce. If this values is too small,
* ppp process eats many CPU time.
*/
#ifndef SIGALRM
usleep(TICKUNIT);
TimerService();
#else
handle_signals();
#endif
/* If there are aren't many packets queued, look for some more. */
if (qlen < 20 && tun_in >= 0) {
if (tun_in + 1 > nfds)
nfds = tun_in + 1;
FD_SET(tun_in, &rfds);
}
if (netfd >= 0) {
if (netfd + 1 > nfds)
nfds = netfd + 1;
FD_SET(netfd, &rfds);
FD_SET(netfd, &efds);
}
#ifndef SIGALRM
/*
* Normally, select() will not block because modem is writable. In AUTO
* mode, select will block until we find packet from tun
*/
tp = (RedialTimer.state == TIMER_RUNNING) ? &timeout : NULL;
i = select(nfds, &rfds, &wfds, &efds, tp);
#else
/*
* When SIGALRM timer is running, a select function will be return -1 and
* EINTR after a Time Service signal hundler is done. If the redial
* timer is not running and we are trying to dial, poll with a 0 value
* timer.
*/
tp = (dial_up && RedialTimer.state != TIMER_RUNNING) ? &timeout : NULL;
i = select(nfds, &rfds, &wfds, &efds, tp);
#endif
if (i == 0) {
continue;
}
if (i < 0) {
if (errno == EINTR) {
handle_signals();
continue;
}
LogPrintf(LogERROR, "DoLoop: select(): %s\n", strerror(errno));
break;
}
if ((netfd >= 0 && FD_ISSET(netfd, &efds)) || (modem >= 0 && FD_ISSET(modem, &efds))) {
LogPrintf(LogALERT, "Exception detected.\n");
break;
}
if (server >= 0 && FD_ISSET(server, &rfds)) {
LogPrintf(LogPHASE, "connected to client.\n");
wfd = accept(server, (struct sockaddr *) & hisaddr, &ssize);
if (wfd < 0) {
LogPrintf(LogERROR, "DoLoop: accept(): %s\n", strerror(errno));
continue;
}
if (netfd >= 0) {
write(wfd, "already in use.\n", 16);
close(wfd);
continue;
} else
netfd = wfd;
VarTerm = fdopen(netfd, "a+");
mode |= MODE_INTER;
Greetings();
(void) IsInteractive();
Prompt();
}
if ((mode & MODE_INTER) && (netfd >= 0 && FD_ISSET(netfd, &rfds)) &&
((mode & MODE_AUTO) || pgroup == tcgetpgrp(0))) {
/* something to read from tty */
ReadTty();
}
if (modem >= 0) {
if (FD_ISSET(modem, &wfds)) { /* ready to write into modem */
ModemStartOutput(modem);
}
if (FD_ISSET(modem, &rfds)) { /* something to read from modem */
if (LcpFsm.state <= ST_CLOSED)
usleep(10000);
n = read(modem, rbuff, sizeof(rbuff));
if ((mode & MODE_DIRECT) && n <= 0) {
DownConnection();
} else
LogDumpBuff(LogASYNC, "ReadFromModem", rbuff, n);
if (LcpFsm.state <= ST_CLOSED) {
/*
* In dedicated mode, we just discard input until LCP is started.
*/
if (!(mode & MODE_DEDICATED)) {
cp = HdlcDetect(rbuff, n);
if (cp) {
/*
* LCP packet is detected. Turn ourselves into packet mode.
*/
if (cp != rbuff) {
write(modem, rbuff, cp - rbuff);
write(modem, "\r\n", 2);
}
PacketMode();
} else
write(fileno(VarTerm), rbuff, n);
}
} else {
if (n > 0)
AsyncInput(rbuff, n);
}
}
}
if (tun_in >= 0 && FD_ISSET(tun_in, &rfds)) { /* something to read
* from tun */
n = read(tun_in, rbuff, sizeof(rbuff));
if (n < 0) {
LogPrintf(LogERROR, "read from tun: %s\n", strerror(errno));
continue;
}
if (((struct ip *) rbuff)->ip_dst.s_addr == IpcpInfo.want_ipaddr.s_addr) {
/* we've been asked to send something addressed *to* us :( */
if (VarLoopback) {
pri = PacketCheck(rbuff, n, FL_IN);
if (pri >= 0) {
struct mbuf *bp;
if (mode & MODE_ALIAS) {
VarPacketAliasIn(rbuff, sizeof rbuff);
n = ntohs(((struct ip *) rbuff)->ip_len);
}
bp = mballoc(n, MB_IPIN);
bcopy(rbuff, MBUF_CTOP(bp), n);
IpInput(bp);
LogPrintf(LogDEBUG, "Looped back packet addressed to myself\n");
}
continue;
} else
LogPrintf(LogDEBUG, "Oops - forwarding packet addressed to myself\n");
}
/*
* Process on-demand dialup. Output packets are queued within tunnel
* device until IPCP is opened.
*/
if (LcpFsm.state <= ST_CLOSED && (mode & MODE_AUTO)) {
pri = PacketCheck(rbuff, n, FL_DIAL);
if (pri >= 0) {
if (mode & MODE_ALIAS) {
VarPacketAliasOut(rbuff, sizeof rbuff);
n = ntohs(((struct ip *) rbuff)->ip_len);
}
IpEnqueue(pri, rbuff, n);
dial_up = TRUE; /* XXX */
}
continue;
}
pri = PacketCheck(rbuff, n, FL_OUT);
if (pri >= 0) {
if (mode & MODE_ALIAS) {
VarPacketAliasOut(rbuff, sizeof rbuff);
n = ntohs(((struct ip *) rbuff)->ip_len);
}
IpEnqueue(pri, rbuff, n);
}
}
}
LogPrintf(LogDEBUG, "Job (DoLoop) done.\n");
}