freebsd-dev/usr.sbin/ppp/main.c

848 lines
18 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 1.12 1996/01/10 21:27:53 phk 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 <sys/socket.h>
#include <arpa/inet.h>
#include "modem.h"
#include "os.h"
#include "hdlc.h"
#include "ccp.h"
#include "lcp.h"
#include "ipcp.h"
#include "vars.h"
#include "auth.h"
#include "filter.h"
#include "systems.h"
#include "ip.h"
#define LAUTH_M1 "Warning: No password entry for this host in ppp.secret\n"
#define LAUTH_M2 "Warning: All manipulation is allowed by anyone in the world\n"
#ifndef O_NONBLOCK
#ifdef O_NDELAY
#define O_NONBLOCK O_NDELAY
#endif
#endif
extern void VjInit(), AsyncInit();
extern void AsyncInput(), IpOutput();
extern int SelectSystem();
extern void DecodeCommand(), Prompt();
extern int IsInteractive();
extern struct in_addr ifnetmask;
static void DoLoop(void);
static void TerminalStop();
static struct termios oldtio; /* Original tty mode */
static struct termios comtio; /* Command level tty mode */
static int TermMode;
static int server;
struct sockaddr_in ifsin;
char pid_filename[128];
static void
TtyInit()
{
struct termios newtio;
int stat;
stat = fcntl(0, F_GETFL, 0);
stat |= O_NONBLOCK;
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;
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(prompt)
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);
stat |= O_NONBLOCK;
fcntl(0, F_SETFL, stat);
TermMode = 0;
if(prompt) Prompt(0);
}
/*
* 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);
stat &= ~O_NONBLOCK;
fcntl(0, F_SETFL, stat);
TermMode = 1;
}
void
TtyOldMode()
{
int stat;
stat = fcntl(0, F_GETFL, 0);
stat &= ~O_NONBLOCK;
fcntl(0, F_SETFL, stat);
tcsetattr(0, TCSANOW, &oldtio);
}
void
Cleanup(excode)
int excode;
{
OsLinkdown();
OsCloseLink(1);
sleep(1);
if (mode & MODE_AUTO) {
DeleteIfRoutes(1);
unlink(pid_filename);
}
OsInterfaceDown(1);
LogPrintf(LOG_PHASE, "PPP Terminated.\n");
LogClose();
if (server > 0)
close(server);
TtyOldMode();
exit(excode);
}
static void
Hangup()
{
LogPrintf(LOG_PHASE, "SIGHUP\n");
Cleanup(EX_HANGUP);
}
static void
CloseSession()
{
LogPrintf(LOG_PHASE, "SIGTERM\n");
LcpClose();
Cleanup(EX_TERM);
}
static void
TerminalCont()
{
(void)signal(SIGCONT, SIG_DFL);
(void)signal(SIGTSTP, TerminalStop);
TtyCommandMode(getpgrp() == tcgetpgrp(0));
}
static void
TerminalStop(signo)
int signo;
{
(void)signal(SIGCONT, TerminalCont);
TtyOldMode();
signal(SIGTSTP, SIG_DFL);
kill(getpid(), signo);
}
void
Usage()
{
fprintf(stderr, "Usage: ppp [-auto | -direct | -dedicated] [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, "direct") == 0)
mode |= MODE_DIRECT;
else if (strcmp(cp, "dedicated") == 0)
mode |= MODE_DEDICATED;
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()
{
printf("User Process PPP. Written by Toshiharu OHNO.\r\n");
fflush(stdout);
}
void
main(argc, argv)
int argc;
char **argv;
{
int tunno;
argc--; argv++;
mode = MODE_INTER; /* default operation is interactive mode */
netfd = -1;
ProcessArgs(argc, argv);
Greetings();
GetUid();
IpcpDefAddress();
if (SelectSystem("default", CONFFILE) < 0) {
fprintf(stderr, "Warning: No default entry is given in config file.\n");
}
if (LogOpen())
exit(EX_START);
switch ( LocalAuthInit() ) {
case NOT_FOUND:
fprintf(stderr,LAUTH_M1);
fprintf(stderr,LAUTH_M2);
fflush (stderr);
/* Fall down */
case VALID:
VarLocalAuth = LOCAL_AUTH;
break;
default:
break;
}
if (OpenTunnel(&tunno) < 0) {
perror("open_tun");
exit(EX_START);
}
if (mode & (MODE_AUTO|MODE_DIRECT|MODE_DEDICATED))
mode &= ~MODE_INTER;
if (mode & MODE_INTER) {
printf("Interactive mode\n");
netfd = 0;
} else if (mode & MODE_AUTO) {
printf("Automatic mode\n");
if (dstsystem == NULL) {
fprintf(stderr, "Destination system must be specified in auto mode.\n");
exit(EX_START);
}
}
tcgetattr(0, &oldtio); /* Save original tty mode */
signal(SIGHUP, Hangup);
signal(SIGTERM, CloseSession);
signal(SIGINT, CloseSession);
signal(SIGQUIT, CloseSession);
#ifdef SIGSEGV
signal(SIGSEGV, Hangup);
#endif
#ifdef SIGPIPE
signal(SIGPIPE, Hangup);
#endif
#ifdef SIGALRM
signal(SIGALRM, SIG_IGN);
#endif
if(mode & MODE_INTER)
{
#ifdef SIGTSTP
signal(SIGTSTP, TerminalStop);
#endif
#ifdef SIGTTIN
signal(SIGTTIN, TerminalStop);
#endif
#ifdef SIGTTOU
signal(SIGTTOU, SIG_IGN);
#endif
}
if (dstsystem) {
if (SelectSystem(dstsystem, CONFFILE) < 0) {
fprintf(stderr, "Destination system not found in conf file.\n");
Cleanup(EX_START);
}
if ((mode & MODE_AUTO) && DefHisAddress.ipaddr.s_addr == INADDR_ANY) {
fprintf(stderr, "Must specify dstaddr with auto mode.\n");
Cleanup(EX_START);
}
}
if (mode & MODE_DIRECT)
printf("Packet mode enabled.\n");
#ifdef notdef
if (mode & MODE_AUTO) {
OsSetIpaddress(IpcpInfo.want_ipaddr, IpcpInfo.his_ipaddr, ifnetmask);
}
#endif
if (!(mode & MODE_INTER)) {
int port = SERVER_PORT + tunno;
/*
* Create server socket and listen at there.
*/
server = socket(PF_INET, SOCK_STREAM, 0);
if (server < 0) {
perror("socket");
Cleanup(EX_SOCK);
}
ifsin.sin_family = AF_INET;
ifsin.sin_addr.s_addr = INADDR_ANY;
ifsin.sin_port = htons(port);
if (bind(server, (struct sockaddr *) &ifsin, sizeof(ifsin)) < 0) {
perror("bind");
if (errno == EADDRINUSE)
fprintf(stderr, "Wait for a while, then try again.\n");
Cleanup(EX_SOCK);
}
listen(server, 5);
DupLog();
if (!(mode & MODE_DIRECT)) {
int fd;
char pid[32];
if (fork())
exit(0);
snprintf(pid_filename, sizeof (pid_filename), "%s/PPP.%s",
_PATH_VARRUN, dstsystem);
unlink(pid_filename);
sprintf(pid, "%lu\n", getpid());
if ((fd = open(pid_filename, O_RDWR|O_CREAT, 0666)) != -1)
{
write(fd, pid, strlen(pid));
close(fd);
}
}
LogPrintf(LOG_PHASE, "Listening at %d.\n", port);
#ifdef DOTTYINIT
if (mode & (MODE_DIRECT|MODE_DEDICATED)) { /* } */
#else
if (mode & MODE_DIRECT) {
#endif
TtyInit();
} else {
setsid(); /* detach control tty */
}
} else {
server = -1;
TtyInit();
TtyCommandMode(1);
}
LogPrintf(LOG_PHASE, "PPP Started.\n");
do
DoLoop();
while (mode & MODE_DEDICATED);
Cleanup(EX_DONE);
}
/*
* Turn into packet mode, where we speek PPP.
*/
void
PacketMode()
{
if (RawModem(modem) < 0) {
fprintf(stderr, "Not connected.\r\n");
return;
}
AsyncInit();
VjInit();
LcpInit();
IpcpInit();
CcpInit();
LcpUp();
if (mode & (MODE_DIRECT|MODE_DEDICATED))
LcpOpen(OPEN_ACTIVE);
else
LcpOpen(VarOpenMode);
if ((mode & (MODE_INTER|MODE_AUTO)) == MODE_INTER) {
TtyCommandMode(1);
fprintf(stderr, "Packet mode.\r\n");
}
}
static void
ShowHelp()
{
fprintf(stderr, "The following commands are available:\r\n");
fprintf(stderr, " ~p\tEnter to Packet mode\r\n");
fprintf(stderr, " ~.\tTerminate program\r\n");
}
static void
ReadTty()
{
int n;
char ch;
static int ttystate;
#define MAXLINESIZE 200
char linebuff[MAXLINESIZE];
#ifdef DEBUG
logprintf("termode = %d, netfd = %d, mode = %d\n", TermMode, netfd, mode);
#endif
if (!TermMode) {
n = read(netfd, linebuff, sizeof(linebuff)-1);
if (n > 0) {
DecodeCommand(linebuff, n, 1);
} else {
#ifdef DEBUG
logprintf("connection closed.\n");
#endif
close(netfd);
netfd = -1;
mode &= ~MODE_INTER;
}
return;
}
/*
* We are in terminal mode, decode special sequences
*/
n = read(0, &ch, 1);
#ifdef DEBUG
logprintf("got %d bytes\n", n);
#endif
if (n > 0) {
switch (ttystate) {
case 0:
if (ch == '~')
ttystate++;
else
write(modem, &ch, n);
break;
case 1:
switch (ch) {
case '?':
ShowHelp();
break;
case '-':
if (loglevel > 0) {
loglevel--;
fprintf(stderr, "New loglevel is %d\r\n", loglevel);
}
break;
case '+':
loglevel++;
fprintf(stderr, "New loglevel is %d\r\n", loglevel);
break;
#ifdef DEBUG
case 'm':
ShowMemMap();
break;
#endif
case 'p':
/*
* XXX: Should check carrier.
*/
if (LcpFsm.state <= ST_CLOSED) {
VarOpenMode = OPEN_ACTIVE;
PacketMode();
}
break;
#ifdef DEBUG
case 't':
ShowTimers();
break;
#endif
case '.':
TermMode = 1;
TtyCommandMode(1);
break;
default:
if (write(modem, &ch, n) < 0)
fprintf(stderr, "err in write.\r\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(cp, n)
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(LOG_PHASE, "Redialing timer expired.\n");
}
static void
StartRedialTimer()
{
StopTimer(&RedialTimer);
if (VarRedialTimeout) {
LogPrintf(LOG_PHASE, "Enter pause for redialing.\n");
RedialTimer.state = TIMER_STOPPED;
if (VarRedialTimeout > 0)
RedialTimer.load = VarRedialTimeout * SECTICKS;
else
RedialTimer.load = (random() % REDIAL_PERIOD) * SECTICKS;
RedialTimer.func = RedialTimeout;
StartTimer(&RedialTimer);
}
}
static void
DoLoop()
{
fd_set rfds, wfds, efds;
int pri, i, n, wfd;
struct sockaddr_in hisaddr;
struct timeval timeout, *tp;
int ssize = sizeof(hisaddr);
u_char *cp;
u_char rbuff[MAX_MRU];
int dial_up;
int tries;
int qlen;
pid_t pgroup;
pgroup = getpgrp();
if (mode & MODE_DIRECT) {
modem = OpenModem(mode);
LogPrintf(LOG_PHASE, "Packet mode enabled\n");
PacketMode();
} else if (mode & MODE_DEDICATED) {
if (!modem)
modem = OpenModem(mode);
}
fflush(stdout);
timeout.tv_sec = 0;
timeout.tv_usec = 0;
dial_up = FALSE; /* XXXX */
tries = 0;
for (;;) {
if ( modem )
IpStartOutput();
FD_ZERO(&rfds); FD_ZERO(&wfds); FD_ZERO(&efds);
/*
* If Ip packet for output is enqueued and require dial up,
* Just do it!
*/
if ( dial_up && RedialTimer.state != TIMER_RUNNING ) { /* XXX */
#ifdef DEBUG
logprintf("going to dial: modem = %d\n", modem);
#endif
modem = OpenModem(mode);
if (modem < 0) {
modem = 0; /* Set intial value for next OpenModem */
StartRedialTimer();
} else {
tries++;
LogPrintf(LOG_CHAT, "Dial attempt %u\n", tries);
if (DialModem()) {
sleep(1); /* little pause to allow peer starts */
ModemTimeout();
PacketMode();
dial_up = FALSE;
tries = 0;
} else {
CloseModem();
/* Dial failed. Keep quite during redial wait period. */
StartRedialTimer();
if (VarDialTries && tries >= VarDialTries) {
dial_up = FALSE;
tries = 0;
}
}
}
}
qlen = ModemQlen();
if (modem) {
FD_SET(modem, &rfds);
FD_SET(modem, &efds);
if (qlen > 0) {
FD_SET(modem, &wfds);
}
}
if (server > 0) 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();
#endif
/* If there are aren't many packets queued, look for some more. */
if (qlen < 20)
FD_SET(tun_in, &rfds);
if (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(tun_in+10, &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(tun_in+10, &rfds, &wfds, &efds, tp);
#endif
if ( i == 0 ) {
continue;
}
if ( i < 0 ) {
if ( errno == EINTR ) {
continue; /* Got SIGALRM, Do check a queue for dialing */
}
perror("select");
break;
}
if ((netfd > 0 && FD_ISSET(netfd, &efds)) || FD_ISSET(modem, &efds)) {
logprintf("Exception detected.\n");
break;
}
if (server > 0 && FD_ISSET(server, &rfds)) {
#ifdef DEBUG
logprintf("connected to client.\n");
#endif
wfd = accept(server, (struct sockaddr *)&hisaddr, &ssize);
if (netfd > 0) {
write(wfd, "already in use.\n", 16);
close(wfd);
continue;
} else
netfd = wfd;
if (dup2(netfd, 1) < 0)
perror("dup2");
mode |= MODE_INTER;
Greetings();
switch ( LocalAuthInit() ) {
case NOT_FOUND:
fprintf(stdout,LAUTH_M1);
fprintf(stdout,LAUTH_M2);
fflush(stdout);
/* Fall down */
case VALID:
VarLocalAuth = LOCAL_AUTH;
break;
default:
break;
}
(void) IsInteractive();
Prompt(0);
}
if ((mode & MODE_INTER) && FD_ISSET(netfd, &rfds) &&
((mode & MODE_AUTO) || pgroup == tcgetpgrp(0))) {
/* something to read from tty */
ReadTty();
}
if (modem) {
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(LOG_ASYNC, "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(1, rbuff, cp - rbuff);
write(1, "\r\n", 2);
}
PacketMode();
#ifdef notdef
AsyncInput(cp, n - (cp - rbuff));
#endif
} else
write(1, rbuff, n);
}
} else {
if (n > 0)
AsyncInput(rbuff, n);
#ifdef notdef
continue; /* THIS LINE RESULT AS POOR PERFORMANCE */
#endif
}
}
}
if (FD_ISSET(tun_in, &rfds)) { /* something to read from tun */
n = read(tun_in, rbuff, sizeof(rbuff));
if (n < 0) {
perror("read from tun");
continue;
}
/*
* 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) {
IpEnqueue(pri, rbuff, n);
dial_up = TRUE; /* XXX */
}
continue;
}
pri = PacketCheck(rbuff, n, FL_OUT);
if (pri >= 0)
IpEnqueue(pri, rbuff, n);
}
}
logprintf("job done.\n");
}