/*
* 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 1.154 1999/05/08 11:07:05 brian Exp $
*
* TODO:
*/
#include <sys/param.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <sys/un.h>
#include <errno.h>
#include <fcntl.h>
#include <paths.h>
#include <signal.h>
#include <stdio.h>
#include <string.h>
#include <sys/time.h>
#include <termios.h>
#include <unistd.h>
#ifndef NOALIAS
#ifdef __FreeBSD__
#include <alias.h>
#else
#include "alias.h"
#endif
#endif
#include "layer.h"
#include "probe.h"
#include "mbuf.h"
#include "log.h"
#include "defs.h"
#include "id.h"
#include "timer.h"
#include "fsm.h"
#include "lqr.h"
#include "hdlc.h"
#include "lcp.h"
#include "ccp.h"
#include "iplist.h"
#include "throughput.h"
#include "slcompress.h"
#include "ipcp.h"
#include "filter.h"
#include "descriptor.h"
#include "link.h"
#include "mp.h"
#ifndef NORADIUS
#include "radius.h"
#endif
#include "bundle.h"
#include "auth.h"
#include "systems.h"
#include "sig.h"
#include "main.h"
#include "server.h"
#include "prompt.h"
#include "chat.h"
#include "chap.h"
#include "cbcp.h"
#include "datalink.h"
#include "iface.h"
#ifndef O_NONBLOCK
#ifdef O_NDELAY
#define O_NONBLOCK O_NDELAY
#endif
#endif
static void DoLoop(struct bundle *);
static void TerminalStop(int);
static const char *ex_desc(int);
static struct bundle *SignalBundle;
static struct prompt *SignalPrompt;
void
Cleanup(int excode)
{
SignalBundle->CleaningUp = 1;
bundle_Close(SignalBundle, NULL, CLOSE_STAYDOWN);
}
void
AbortProgram(int excode)
{
server_Close(SignalBundle);
log_Printf(LogPHASE, "PPP Terminated (%s).\n", ex_desc(excode));
bundle_Close(SignalBundle, NULL, CLOSE_STAYDOWN);
bundle_Destroy(SignalBundle);
log_Close();
exit(excode);
}
static void
CloseConnection(int signo)
{
/* NOTE, these are manual, we've done a setsid() */
sig_signal(SIGINT, SIG_IGN);
log_Printf(LogPHASE, "Caught signal %d, abort connection(s)\n", signo);
bundle_Down(SignalBundle, CLOSE_STAYDOWN);
sig_signal(SIGINT, CloseConnection);
}
static void
CloseSession(int signo)
{
log_Printf(LogPHASE, "Signal %d, terminate.\n", signo);
Cleanup(EX_TERM);
}
static pid_t BGPid = 0;
static void
KillChild(int signo)
{
signal(signo, SIG_IGN);
log_Printf(LogPHASE, "Parent: Signal %d\n", signo);
kill(BGPid, SIGINT);
}
static void
TerminalCont(int signo)
{
signal(SIGCONT, SIG_DFL);
prompt_Continue(SignalPrompt);
}
static void
TerminalStop(int signo)
{
prompt_Suspend(SignalPrompt);
signal(SIGCONT, TerminalCont);
raise(SIGSTOP);
}
static void
BringDownServer(int signo)
{
/* Drops all child prompts too ! */
server_Close(SignalBundle);
}
static const char *
ex_desc(int ex)
{
static char num[12]; /* Used immediately if returned */
static const 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;
}
static void
Usage(void)
{
fprintf(stderr,
"Usage: ppp [-auto | -background | -direct | -dedicated | -ddial ]"
#ifndef NOALIAS
" [ -alias ]"
#endif
" [system ...]\n");
exit(EX_START);
}
static int
ProcessArgs(int argc, char **argv, int *mode, int *alias)
{
int optc, newmode, arg;
char *cp;
optc = 0;
*mode = PHYS_INTERACTIVE;
*alias = 0;
for (arg = 1; arg < argc && *argv[arg] == '-'; arg++, optc++) {
cp = argv[arg] + 1;
newmode = Nam2mode(cp);
switch (newmode) {
case PHYS_NONE:
if (strcmp(cp, "alias") == 0) {
#ifdef NOALIAS
log_Printf(LogWARN, "Cannot load alias library (compiled out)\n");
#else
*alias = 1;
#endif
optc--; /* this option isn't exclusive */
} else
Usage();
break;
case PHYS_ALL:
Usage();
break;
default:
*mode = newmode;
}
}
if (optc > 1) {
fprintf(stderr, "You may specify only one mode.\n");
exit(EX_START);
}
if (*mode == PHYS_AUTO && arg == argc) {
fprintf(stderr, "A system must be specified in auto mode.\n");
exit(EX_START);
}
return arg; /* Don't SetLabel yet ! */
}
static void
CheckLabel(const char *label, struct prompt *prompt, int mode)
{
const char *err;
if ((err = system_IsValid(label, prompt, mode)) != NULL) {
fprintf(stderr, "%s: %s\n", label, err);
if (mode == PHYS_DIRECT)
log_Printf(LogWARN, "Label %s rejected -direct connection: %s\n",
label, err);
log_Close();
exit(1);
}
}
int
main(int argc, char **argv)
{
char *name;
const char *lastlabel;
int nfds, mode, alias, label, arg;
struct bundle *bundle;
struct prompt *prompt;
nfds = getdtablesize();
if (nfds >= FD_SETSIZE)
/*
* If we've got loads of file descriptors, make sure they're all
* closed. If they aren't, we may end up with a seg fault when our
* `fd_set's get too big when select()ing !
*/
while (--nfds > 2)
close(nfds);
name = strrchr(argv[0], '/');
log_Open(name ? name + 1 : argv[0]);
#ifndef NOALIAS
PacketAliasInit();
#endif
label = ProcessArgs(argc, argv, &mode, &alias);
/*
* A FreeBSD & OpenBSD hack to dodge a bug in the tty driver that drops
* output occasionally.... I must find the real reason some time. To
* display the dodgy behaviour, comment out this bit, make yourself a large
* routing table and then run ppp in interactive mode. The `show route'
* command will drop chunks of data !!!
*/
if (mode == PHYS_INTERACTIVE) {
close(STDIN_FILENO);
if (open(_PATH_TTY, O_RDONLY) != STDIN_FILENO) {
fprintf(stderr, "Cannot open %s for input !\n", _PATH_TTY);
return 2;
}
}
/* Allow output for the moment (except in direct mode) */
if (mode == PHYS_DIRECT)
prompt = NULL;
else
SignalPrompt = prompt = prompt_Create(NULL, NULL, PROMPT_STD);
ID0init();
if (ID0realuid() != 0) {
char conf[200], *ptr;
snprintf(conf, sizeof conf, "%s/%s", _PATH_PPP, CONFFILE);
do {
if (!access(conf, W_OK)) {
log_Printf(LogALERT, "ppp: Access violation: Please protect %s\n",
conf);
return -1;
}
ptr = conf + strlen(conf)-2;
while (ptr > conf && *ptr != '/')
*ptr-- = '\0';
} while (ptr >= conf);
}
if (label < argc)
for (arg = label; arg < argc; arg++)
CheckLabel(argv[arg], prompt, mode);
else
CheckLabel("default", prompt, mode);
prompt_Printf(prompt, "Working in %s mode\n", mode2Nam(mode));
if ((bundle = bundle_Create(TUN_PREFIX, mode, (const char **)argv)) == NULL) {
log_Printf(LogWARN, "bundle_Create: %s\n", strerror(errno));
return EX_START;
}
/* NOTE: We may now have changed argv[1] via a ``set proctitle'' */
if (prompt) {
prompt->bundle = bundle; /* couldn't do it earlier */
prompt_Printf(prompt, "Using interface: %s\n", bundle->iface->name);
}
SignalBundle = bundle;
bundle->AliasEnabled = alias;
if (alias)
bundle->cfg.opt |= OPT_IFACEALIAS;
if (system_Select(bundle, "default", CONFFILE, prompt, NULL) < 0)
prompt_Printf(prompt, "Warning: No default entry found in config file.\n");
sig_signal(SIGHUP, CloseSession);
sig_signal(SIGTERM, CloseSession);
sig_signal(SIGINT, CloseConnection);
sig_signal(SIGQUIT, CloseSession);
sig_signal(SIGALRM, SIG_IGN);
signal(SIGPIPE, SIG_IGN);
if (mode == PHYS_INTERACTIVE)
sig_signal(SIGTSTP, TerminalStop);
sig_signal(SIGUSR2, BringDownServer);
lastlabel = argc == 2 ? bundle->argv1 : argv[argc - 1];
for (arg = label; arg < argc; arg++) {
/* In case we use LABEL or ``set enddisc label'' */
bundle_SetLabel(bundle, lastlabel);
system_Select(bundle, arg == 1 ? bundle->argv1 : argv[arg],
CONFFILE, prompt, NULL);
}
if (label < argc)
/* In case the last label did a ``load'' */
bundle_SetLabel(bundle, lastlabel);
if (mode == PHYS_AUTO &&
bundle->ncp.ipcp.cfg.peer_range.ipaddr.s_addr == INADDR_ANY) {
prompt_Printf(prompt, "You must ``set ifaddr'' with a peer address "
"in auto mode.\n");
AbortProgram(EX_START);
}
if (mode != PHYS_INTERACTIVE) {
if (mode != PHYS_DIRECT) {
int bgpipe[2];
pid_t bgpid;
if (mode == PHYS_BACKGROUND && pipe(bgpipe)) {
log_Printf(LogERROR, "pipe: %s\n", strerror(errno));
AbortProgram(EX_SOCK);
}
bgpid = fork();
if (bgpid == -1) {
log_Printf(LogERROR, "fork: %s\n", strerror(errno));
AbortProgram(EX_SOCK);
}
if (bgpid) {
char c = EX_NORMAL;
if (mode == PHYS_BACKGROUND) {
close(bgpipe[1]);
BGPid = bgpid;
/* If we get a signal, kill the child */
signal(SIGHUP, KillChild);
signal(SIGTERM, KillChild);
signal(SIGINT, KillChild);
signal(SIGQUIT, KillChild);
/* Wait for our child to close its pipe before we exit */
if (read(bgpipe[0], &c, 1) != 1) {
prompt_Printf(prompt, "Child exit, no status.\n");
log_Printf(LogPHASE, "Parent: Child exit, no status.\n");
} else if (c == EX_NORMAL) {
prompt_Printf(prompt, "PPP enabled.\n");
log_Printf(LogPHASE, "Parent: PPP enabled.\n");
} else {
prompt_Printf(prompt, "Child failed (%s).\n", ex_desc((int) c));
log_Printf(LogPHASE, "Parent: Child failed (%s).\n",
ex_desc((int) c));
}
close(bgpipe[0]);
}
return c;
} else if (mode == PHYS_BACKGROUND) {
close(bgpipe[0]);
bundle->notify.fd = bgpipe[1];
}
bundle_LockTun(bundle); /* we have a new pid */
/* -auto, -dedicated, -ddial & -background */
prompt_Destroy(prompt, 0);
close(STDOUT_FILENO);
close(STDERR_FILENO);
close(STDIN_FILENO);
setsid();
} else {
/* -direct: STDIN_FILENO gets used by modem_Open */
prompt_TtyInit(NULL);
close(STDOUT_FILENO);
close(STDERR_FILENO);
}
} else {
/* Interactive mode */
close(STDERR_FILENO);
prompt_TtyInit(prompt);
prompt_TtyCommandMode(prompt);
prompt_Required(prompt);
}
log_Printf(LogPHASE, "PPP Started (%s mode).\n", mode2Nam(mode));
DoLoop(bundle);
AbortProgram(EX_NORMAL);
return EX_NORMAL;
}
static void
DoLoop(struct bundle *bundle)
{
fd_set rfds, wfds, efds;
int i, nfds, nothing_done;
struct probe probe;
probe_Init(&probe);
do {
nfds = 0;
FD_ZERO(&rfds);
FD_ZERO(&wfds);
FD_ZERO(&efds);
/* All our datalinks, the tun device and the MP socket */
descriptor_UpdateSet(&bundle->desc, &rfds, &wfds, &efds, &nfds);
/* All our prompts and the diagnostic socket */
descriptor_UpdateSet(&server.desc, &rfds, NULL, NULL, &nfds);
if (bundle_IsDead(bundle))
/* Don't select - we'll be here forever */
break;
/*
* It's possible that we've had a signal since we last checked. If
* we don't check again before calling select(), we may end up stuck
* after having missed the event.... sig_Handle() tries to be as
* quick as possible if nothing is likely to have happened.
* This is only really likely if we block in open(... O_NONBLOCK)
* which will happen with a misconfigured device.
*/
if (sig_Handle())
continue;
i = select(nfds, &rfds, &wfds, &efds, NULL);
if (i < 0 && errno != EINTR) {
log_Printf(LogERROR, "DoLoop: select(): %s\n", strerror(errno));
if (log_IsKept(LogTIMER)) {
struct timeval t;
for (i = 0; i <= nfds; i++) {
if (FD_ISSET(i, &rfds)) {
log_Printf(LogTIMER, "Read set contains %d\n", i);
FD_CLR(i, &rfds);
t.tv_sec = t.tv_usec = 0;
if (select(nfds, &rfds, &wfds, &efds, &t) != -1) {
log_Printf(LogTIMER, "The culprit !\n");
break;
}
}
if (FD_ISSET(i, &wfds)) {
log_Printf(LogTIMER, "Write set contains %d\n", i);
FD_CLR(i, &wfds);
t.tv_sec = t.tv_usec = 0;
if (select(nfds, &rfds, &wfds, &efds, &t) != -1) {
log_Printf(LogTIMER, "The culprit !\n");
break;
}
}
if (FD_ISSET(i, &efds)) {
log_Printf(LogTIMER, "Error set contains %d\n", i);
FD_CLR(i, &efds);
t.tv_sec = t.tv_usec = 0;
if (select(nfds, &rfds, &wfds, &efds, &t) != -1) {
log_Printf(LogTIMER, "The culprit !\n");
break;
}
}
}
}
break;
}
log_Printf(LogTIMER, "Select returns %d\n", i);
sig_Handle();
if (i <= 0)
continue;
for (i = 0; i <= nfds; i++)
if (FD_ISSET(i, &efds)) {
log_Printf(LogPHASE, "Exception detected on descriptor %d\n", i);
/* We deal gracefully with link descriptor exceptions */
if (!bundle_Exception(bundle, i)) {
log_Printf(LogERROR, "Exception cannot be handled !\n");
break;
}
}
if (i <= nfds)
break;
nothing_done = 1;
if (descriptor_IsSet(&server.desc, &rfds)) {
descriptor_Read(&server.desc, bundle, &rfds);
nothing_done = 0;
}
if (descriptor_IsSet(&bundle->desc, &rfds)) {
descriptor_Read(&bundle->desc, bundle, &rfds);
nothing_done = 0;
}
if (descriptor_IsSet(&bundle->desc, &wfds))
if (!descriptor_Write(&bundle->desc, bundle, &wfds) && nothing_done) {
/*
* This is disasterous. The OS has told us that something is
* writable, and all our write()s have failed. Rather than
* going back immediately to do our UpdateSet()s and select(),
* we sleep for a bit to avoid gobbling up all cpu time.
*/
struct timeval t;
t.tv_sec = 0;
t.tv_usec = 100000;
select(0, NULL, NULL, NULL, &t);
}
} while (bundle_CleanDatalinks(bundle), !bundle_IsDead(bundle));
log_Printf(LogDEBUG, "DoLoop done.\n");
}
