freebsd-dev/usr.sbin/ppp/main.c
1998-03-25 00:59:38 +00:00

632 lines
16 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 1.121.2.36 1998/03/20 19:48:11 brian Exp $
*
* TODO:
* o Add commands for traffic summary, version display, etc.
* o Add signal handler for misc controls.
*/
#include <sys/param.h>
#include <sys/time.h>
#include <sys/select.h>
#include <sys/socket.h>
#include <net/if.h>
#include <net/if_tun.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <arpa/inet.h>
#include <errno.h>
#include <fcntl.h>
#include <paths.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/time.h>
#include <sys/wait.h>
#include <termios.h>
#include <unistd.h>
#include "command.h"
#include "mbuf.h"
#include "log.h"
#include "defs.h"
#include "id.h"
#include "timer.h"
#include "fsm.h"
#include "modem.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 "bundle.h"
#include "loadalias.h"
#include "vars.h"
#include "auth.h"
#include "systems.h"
#include "ip.h"
#include "sig.h"
#include "main.h"
#include "vjcomp.h"
#include "async.h"
#include "pathnames.h"
#include "tun.h"
#include "route.h"
#include "link.h"
#include "physical.h"
#include "server.h"
#include "prompt.h"
#include "chat.h"
#include "chap.h"
#include "datalink.h"
#ifndef O_NONBLOCK
#ifdef O_NDELAY
#define O_NONBLOCK O_NDELAY
#endif
#endif
static pid_t BGPid = 0;
static char pid_filename[MAXPATHLEN];
static void DoLoop(struct bundle *);
static void TerminalStop(int);
static const char *ex_desc(int);
static struct bundle *SignalBundle;
void
Cleanup(int excode)
{
SignalBundle->CleaningUp = 1;
if (bundle_Phase(SignalBundle) != PHASE_DEAD)
bundle_Close(SignalBundle, NULL, 0);
}
void
AbortProgram(int excode)
{
prompt_Drop(&prompt, 1);
ServerClose();
ID0unlink(pid_filename);
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));
prompt_TtyOldMode(&prompt);
bundle_Close(SignalBundle, NULL, 1);
bundle_Destroy(SignalBundle);
LogClose();
exit(excode);
}
static void
CloseConnection(int signo)
{
/* NOTE, these are manual, we've done a setsid() */
pending_signal(SIGINT, SIG_IGN);
LogPrintf(LogPHASE, "Caught signal %d, abort connection\n", signo);
/* XXX close 'em all ! */
link_Close(bundle2link(SignalBundle, NULL), SignalBundle, 0, 1);
pending_signal(SIGINT, CloseConnection);
}
static void
CloseSession(int signo)
{
if (BGPid) {
kill(BGPid, SIGINT);
exit(EX_TERM);
}
LogPrintf(LogPHASE, "Signal %d, terminate.\n", signo);
Cleanup(EX_TERM);
}
static void
TerminalCont(int signo)
{
pending_signal(SIGCONT, SIG_DFL);
pending_signal(SIGTSTP, TerminalStop);
prompt_TtyCommandMode(&prompt);
if (getpgrp() == prompt_pgrp(&prompt))
prompt_Display(&prompt, SignalBundle);
}
static void
TerminalStop(int signo)
{
pending_signal(SIGCONT, TerminalCont);
prompt_TtyOldMode(&prompt);
pending_signal(SIGTSTP, SIG_DFL);
kill(getpid(), signo);
}
static void
SetUpServer(int signo)
{
int res;
VarHaveLocalAuthKey = 0;
LocalAuthInit();
if ((res = ServerTcpOpen(SERVER_PORT + SignalBundle->unit)) != 0)
LogPrintf(LogERROR, "SIGUSR1: Failed %d to open port %d\n",
res, SERVER_PORT + SignalBundle->unit);
}
static void
BringDownServer(int signo)
{
VarHaveLocalAuthKey = 0;
LocalAuthInit();
ServerClose();
}
static const char *
ex_desc(int ex)
{
static char num[12];
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 char *
ProcessArgs(int argc, char **argv)
{
int optc;
char *cp;
optc = 0;
mode = MODE_INTER;
while (argc > 0 && **argv == '-') {
cp = *argv + 1;
if (strcmp(cp, "auto") == 0) {
mode |= MODE_AUTO;
mode &= ~MODE_INTER;
} else if (strcmp(cp, "background") == 0) {
mode |= MODE_BACKGROUND;
mode &= ~MODE_INTER;
} else if (strcmp(cp, "direct") == 0) {
mode |= MODE_DIRECT;
mode &= ~MODE_INTER;
} else if (strcmp(cp, "dedicated") == 0) {
mode |= MODE_DEDICATED;
mode &= ~MODE_INTER;
} else if (strcmp(cp, "ddial") == 0) {
mode |= MODE_DDIAL;
mode &= ~MODE_INTER;
#ifndef NOALIAS
} 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 */
#endif
} else
Usage();
optc++;
argv++;
argc--;
}
if (argc > 1) {
fprintf(stderr, "specify only one system label.\n");
exit(EX_START);
}
if (optc > 1) {
fprintf(stderr, "specify only one mode.\n");
exit(EX_START);
}
return argc == 1 ? *argv : NULL; /* Don't SetLabel yet ! */
}
int
main(int argc, char **argv)
{
FILE *lockfile;
char *name, *label;
int nfds;
struct bundle *bundle;
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], '/');
LogOpen(name ? name + 1 : argv[0]);
argc--;
argv++;
label = ProcessArgs(argc, argv);
#ifdef __FreeBSD__
/*
* A FreeBSD 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 & MODE_INTER) {
close(STDIN_FILENO);
if (open(_PATH_TTY, O_RDONLY) != STDIN_FILENO) {
fprintf(stderr, "Cannot open %s for input !\n", _PATH_TTY);
return 2;
}
}
#endif
prompt_Init(&prompt, (mode & MODE_DIRECT) ? PROMPT_NONE : 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)) {
LogPrintf(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 (!ValidSystem(label)) {
fprintf(stderr, "You may not use ppp in this mode with this label\n");
if (mode & MODE_DIRECT) {
const char *l;
l = label ? label : "default";
LogPrintf(LogWARN, "Label %s rejected -direct connection\n", l);
}
LogClose();
return 1;
}
if (mode & MODE_INTER)
VarLocalAuth = LOCAL_AUTH;
if ((bundle = bundle_Create("/dev/tun")) == NULL) {
LogPrintf(LogWARN, "bundle_Create: %s\n", strerror(errno));
return EX_START;
}
if (!GetShortHost())
return 1;
IsInteractive(1);
SignalBundle = bundle;
if (SelectSystem(bundle, "default", CONFFILE) < 0)
prompt_Printf(&prompt,
"Warning: No default entry is given in config file.\n");
if ((mode & MODE_OUTGOING_DAEMON) && !(mode & MODE_DEDICATED))
if (label == NULL) {
prompt_Printf(&prompt, "Destination system must be specified in"
" auto, background or ddial mode.\n");
return EX_START;
}
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
}
if (!(mode & MODE_INTER)) {
#ifdef SIGUSR1
pending_signal(SIGUSR1, SetUpServer);
#endif
#ifdef SIGUSR2
pending_signal(SIGUSR2, BringDownServer);
#endif
}
if (label) {
if (SelectSystem(bundle, label, CONFFILE) < 0) {
LogPrintf(LogWARN, "Destination system %s not found in conf file.\n",
GetLabel());
Cleanup(EX_START);
}
/*
* We don't SetLabel() 'till now in case SelectSystem() has an
* embeded load "otherlabel" command.
*/
SetLabel(label);
if (mode & MODE_AUTO &&
bundle->ncp.ipcp.cfg.peer_range.ipaddr.s_addr == INADDR_ANY) {
LogPrintf(LogWARN, "You must \"set ifaddr\" in label %s for auto mode.\n",
label);
Cleanup(EX_START);
}
}
if (mode & MODE_DAEMON) {
if (mode & MODE_BACKGROUND) {
if (pipe(BGFiledes)) {
LogPrintf(LogERROR, "pipe: %s\n", strerror(errno));
Cleanup(EX_SOCK);
}
}
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) {
prompt_Printf(&prompt, "Child exit, no status.\n");
LogPrintf(LogPHASE, "Parent: Child exit, no status.\n");
} else if (c == EX_NORMAL) {
prompt_Printf(&prompt, "PPP enabled.\n");
LogPrintf(LogPHASE, "Parent: PPP enabled.\n");
} else {
prompt_Printf(&prompt, "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]);
}
prompt_Init(&prompt, PROMPT_NONE);
close(STDOUT_FILENO);
close(STDERR_FILENO);
if (mode & MODE_DIRECT)
/* STDIN_FILENO gets used by modem_Open in DIRECT mode */
prompt_TtyInit(&prompt, PROMPT_DONT_WANT_INT);
else if (mode & MODE_DAEMON) {
setsid();
close(STDIN_FILENO);
}
} else {
close(STDERR_FILENO);
prompt_TtyInit(&prompt, PROMPT_WANT_INT);
prompt_TtyCommandMode(&prompt);
prompt_Display(&prompt, bundle);
}
snprintf(pid_filename, sizeof pid_filename, "%stun%d.pid",
_PATH_VARRUN, bundle->unit);
lockfile = ID0fopen(pid_filename, "w");
if (lockfile != NULL) {
fprintf(lockfile, "%d\n", (int) getpid());
fclose(lockfile);
}
#ifndef RELEASE_CRUNCH
else
LogPrintf(LogALERT, "Warning: Can't create %s: %s\n",
pid_filename, strerror(errno));
#endif
LogPrintf(LogPHASE, "PPP Started.\n");
do
DoLoop(bundle);
while (mode & MODE_DEDICATED);
AbortProgram(EX_NORMAL);
return EX_NORMAL;
}
static void
DoLoop(struct bundle *bundle)
{
fd_set rfds, wfds, efds;
int pri, i, n, nfds;
int qlen;
struct tun_data tun;
if (mode & (MODE_DIRECT|MODE_DEDICATED|MODE_BACKGROUND))
bundle_Open(bundle, NULL);
while (!bundle->CleaningUp || bundle_Phase(SignalBundle) != PHASE_DEAD) {
nfds = 0;
FD_ZERO(&rfds);
FD_ZERO(&wfds);
FD_ZERO(&efds);
qlen = bundle_FillQueues(bundle);
handle_signals();
descriptor_UpdateSet(&bundle->desc, &rfds, &wfds, &efds, &nfds);
descriptor_UpdateSet(&server.desc, &rfds, &wfds, &efds, &nfds);
/* If there are aren't many packets queued, look for some more. */
if (qlen < 20 && bundle->tun_fd >= 0) {
if (bundle->tun_fd + 1 > nfds)
nfds = bundle->tun_fd + 1;
FD_SET(bundle->tun_fd, &rfds);
}
descriptor_UpdateSet(&prompt.desc, &rfds, &wfds, &efds, &nfds);
if (bundle->CleaningUp && bundle_Phase(bundle) == PHASE_DEAD)
/* Don't select - we'll be here forever */
break;
i = select(nfds, &rfds, &wfds, &efds, NULL);
if (i == 0)
continue;
if (i < 0) {
if (errno == EINTR) {
handle_signals();
continue;
}
LogPrintf(LogERROR, "DoLoop: select(): %s\n", strerror(errno));
break;
}
for (i = 0; i <= nfds; i++)
if (FD_ISSET(i, &efds)) {
LogPrintf(LogALERT, "Exception detected on descriptor %d\n", i);
break;
}
if (descriptor_IsSet(&server.desc, &rfds))
descriptor_Read(&server.desc, bundle, &rfds);
if (descriptor_IsSet(&prompt.desc, &rfds))
descriptor_Read(&prompt.desc, bundle, &rfds);
if (descriptor_IsSet(&bundle->desc, &wfds))
descriptor_Write(&bundle->desc, bundle, &wfds);
if (descriptor_IsSet(&bundle->desc, &rfds))
descriptor_Read(&bundle->desc, bundle, &rfds);
if (bundle->tun_fd >= 0 && FD_ISSET(bundle->tun_fd, &rfds)) {
/* something to read from tun */
n = read(bundle->tun_fd, &tun, sizeof tun);
if (n < 0) {
LogPrintf(LogERROR, "read from tun: %s\n", strerror(errno));
continue;
}
n -= sizeof tun - sizeof tun.data;
if (n <= 0) {
LogPrintf(LogERROR, "read from tun: Only %d bytes read\n", n);
continue;
}
if (!tun_check_header(tun, AF_INET))
continue;
if (((struct ip *)tun.data)->ip_dst.s_addr ==
bundle->ncp.ipcp.my_ip.s_addr) {
/* we've been asked to send something addressed *to* us :( */
if (VarLoopback) {
pri = PacketCheck(bundle, tun.data, n, &bundle->filter.in);
if (pri >= 0) {
struct mbuf *bp;
#ifndef NOALIAS
if (mode & MODE_ALIAS) {
VarPacketAliasIn(tun.data, sizeof tun.data);
n = ntohs(((struct ip *)tun.data)->ip_len);
}
#endif
bp = mballoc(n, MB_IPIN);
memcpy(MBUF_CTOP(bp), tun.data, n);
IpInput(bundle, 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 (bundle_Phase(bundle) == PHASE_DEAD && (mode & MODE_AUTO) &&
(pri = PacketCheck(bundle, tun.data, n, &bundle->filter.dial)) >= 0)
bundle_Open(bundle, NULL);
pri = PacketCheck(bundle, tun.data, n, &bundle->filter.out);
if (pri >= 0) {
#ifndef NOALIAS
if (mode & MODE_ALIAS) {
VarPacketAliasOut(tun.data, sizeof tun.data);
n = ntohs(((struct ip *)tun.data)->ip_len);
}
#endif
IpEnqueue(pri, tun.data, n);
}
}
}
LogPrintf(LogDEBUG, "Job (DoLoop) done.\n");
}