This commit was manufactured by cvs2svn to create branch 'MP'.

1 files changed, 1101 insertions, 0 deletions

diff --git a/usr.sbin/ppp/main.c b/usr.sbin/ppp/main.c
new file mode 100644
index 000000000000..6418acabb216
--- /dev/null
+++ b/usr.sbin/ppp/main.c
@@ -0,0 +1,1101 @@
+/*
+ *			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 1.120 1998/01/27 23:14:51 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 "os.h"
+#include "hdlc.h"
+#include "lcp.h"
+#include "ccp.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 "main.h"
+#include "vjcomp.h"
+#include "async.h"
+#include "pathnames.h"
+#include "tun.h"
+#include "route.h"
+
+#ifndef O_NONBLOCK
+#ifdef O_NDELAY
+#define	O_NONBLOCK O_NDELAY
+#endif
+#endif
+
+int TermMode = 0;
+int tunno = 0;
+
+static struct termios oldtio;	/* Original tty mode */
+static struct termios comtio;	/* Command level tty mode */
+static pid_t BGPid = 0;
+static char pid_filename[MAXPATHLEN];
+static int dial_up;
+
+static void DoLoop(void);
+static void TerminalStop(int);
+static const char *ex_desc(int);
+
+static void
+TtyInit(int DontWantInt)
+{
+  struct termios newtio;
+  int stat;
+
+  stat = fcntl(netfd, F_GETFL, 0);
+  if (stat > 0) {
+    stat |= O_NONBLOCK;
+    (void) fcntl(netfd, 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(netfd, TCSANOW, &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(netfd, &newtio);
+  newtio.c_lflag |= (ECHO | ISIG | ICANON);
+  newtio.c_iflag = oldtio.c_iflag;
+  newtio.c_oflag |= OPOST;
+  tcsetattr(netfd, TCSADRAIN, &newtio);
+  stat = fcntl(netfd, F_GETFL, 0);
+  if (stat > 0) {
+    stat |= O_NONBLOCK;
+    (void) fcntl(netfd, 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(netfd, TCSADRAIN, &comtio);
+  stat = fcntl(netfd, F_GETFL, 0);
+  if (stat > 0) {
+    stat &= ~O_NONBLOCK;
+    (void) fcntl(netfd, F_SETFL, stat);
+  }
+  TermMode = 1;
+}
+
+void
+TtyOldMode()
+{
+  int stat;
+
+  stat = fcntl(netfd, F_GETFL, 0);
+  if (stat > 0) {
+    stat &= ~O_NONBLOCK;
+    (void) fcntl(netfd, F_SETFL, stat);
+  }
+  tcsetattr(netfd, TCSADRAIN, &oldtio);
+}
+
+void
+Cleanup(int excode)
+{
+  DropClient(1);
+  ServerClose();
+  OsInterfaceDown(1);
+  HangupModem(1);
+  nointr_sleep(1);
+  DeleteIfRoutes(1);
+  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));
+  TtyOldMode();
+  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);
+  reconnectState = RECON_FALSE;
+  reconnectCount = 0;
+  DownConnection();
+  dial_up = 0;
+  pending_signal(SIGINT, CloseConnection);
+}
+
+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(int signo)
+{
+  pending_signal(SIGCONT, SIG_DFL);
+  pending_signal(SIGTSTP, TerminalStop);
+  TtyCommandMode(getpgrp() == tcgetpgrp(netfd));
+}
+
+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;
+
+  VarHaveLocalAuthKey = 0;
+  LocalAuthInit();
+  if ((res = ServerTcpOpen(SERVER_PORT + tunno)) != 0)
+    LogPrintf(LogERROR, "SIGUSR1: Failed %d to open port %d\n",
+	      res, SERVER_PORT + tunno);
+}
+
+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;
+
+  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);
+
+  VarTerm = 0;
+  name = strrchr(argv[0], '/');
+  LogOpen(name ? name + 1 : argv[0]);
+
+  tcgetattr(STDIN_FILENO, &oldtio);	/* Save original tty mode */
+
+  argc--;
+  argv++;
+  label = ProcessArgs(argc, argv);
+  if (!(mode & MODE_DIRECT))
+    VarTerm = stdout;
+
+  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 (!GetShortHost())
+    return 1;
+  IsInteractive(1);
+  IpcpDefAddress();
+
+  if (mode & MODE_INTER)
+    VarLocalAuth = LOCAL_AUTH;
+
+  if (SelectSystem("default", CONFFILE) < 0 && VarTerm)
+    fprintf(VarTerm, "Warning: No default entry is given in config file.\n");
+
+  if (OpenTunnel(&tunno) < 0) {
+    LogPrintf(LogWARN, "OpenTunnel: %s\n", strerror(errno));
+    return EX_START;
+  }
+  CleanInterface(IfDevName);
+  if ((mode & MODE_OUTGOING_DAEMON) && !(mode & MODE_DEDICATED))
+    if (label == NULL) {
+      if (VarTerm)
+	fprintf(VarTerm, "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(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_OUTGOING_DAEMON &&
+	DefHisAddress.ipaddr.s_addr == INADDR_ANY) {
+      LogPrintf(LogWARN, "You must \"set ifaddr\" in label %s for"
+		" auto, background or ddial 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) {
+	    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]);
+    }
+
+    VarTerm = 0;		/* We know it's currently stdout */
+    close(STDOUT_FILENO);
+    close(STDERR_FILENO);
+
+    if (mode & MODE_DIRECT)
+      /* STDIN_FILENO gets used by OpenModem in DIRECT mode */
+      TtyInit(1);
+    else if (mode & MODE_DAEMON) {
+      setsid();
+      close(STDIN_FILENO);
+    }
+  } else {
+    close(STDIN_FILENO);
+    if ((netfd = open(_PATH_TTY, O_RDONLY)) < 0) {
+      fprintf(stderr, "Cannot open %s for intput !\n", _PATH_TTY);
+      return 2;
+    }
+    close(STDERR_FILENO);
+    TtyInit(0);
+    TtyCommandMode(1);
+  }
+
+  snprintf(pid_filename, sizeof pid_filename, "%stun%d.pid",
+           _PATH_VARRUN, tunno);
+  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();
+  while (mode & MODE_DEDICATED);
+
+  Cleanup(EX_DONE);
+  return 0;
+}
+
+/*
+ *  Turn into packet mode, where we speak PPP.
+ */
+void
+PacketMode(int delay)
+{
+  if (RawModem() < 0) {
+    LogPrintf(LogWARN, "PacketMode: Not connected.\n");
+    return;
+  }
+  AsyncInit();
+  VjInit(15);
+  LcpInit();
+  IpcpInit();
+  CcpInit();
+  LcpUp();
+
+  LcpOpen(delay);
+  if (mode & MODE_INTER)
+    TtyCommandMode(1);
+  if (VarTerm) {
+    fprintf(VarTerm, "Packet mode.\n");
+    aft_cmd = 1;
+  }
+}
+
+static void
+ShowHelp(void)
+{
+  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(void)
+{
+  int n;
+  char ch;
+  static int ttystate;
+  char linebuff[LINE_LEN];
+
+  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;
+      if (linebuff[n-1] == '\n')
+        linebuff[--n] = '\0';
+      else
+        linebuff[n] = '\0';
+      if (n)
+        DecodeCommand(linebuff, n, IsInteractive(0) ? NULL : "Client");
+      Prompt();
+    } else if (n <= 0) {
+      LogPrintf(LogPHASE, "Client connection closed.\n");
+      DropClient(0);
+    }
+    return;
+  }
+
+  /*
+   * We are in terminal mode, decode special sequences
+   */
+  n = read(netfd, &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)
+	  PacketMode(0);
+	break;
+      case '.':
+	TermMode = 1;
+	aft_cmd = 1;
+	TtyCommandMode(1);
+	break;
+      case 't':
+	if (LogIsKept(LogDEBUG)) {
+	  ShowTimers();
+	  break;
+	}
+      case 'm':
+	if (LogIsKept(LogDEBUG)) {
+	  ShowMemMap(NULL);
+	  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 const 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,
+};
+
+static const u_char *
+HdlcDetect(u_char * cp, int n)
+{
+  const 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 ((const u_char *) ptr);
+}
+
+static struct pppTimer RedialTimer;
+
+static void
+RedialTimeout(void *v)
+{
+  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);
+  }
+}
+
+#define IN_SIZE sizeof(struct sockaddr_in)
+#define UN_SIZE sizeof(struct sockaddr_in)
+#define ADDRSZ (IN_SIZE > UN_SIZE ? IN_SIZE : UN_SIZE)
+
+static void
+DoLoop(void)
+{
+  fd_set rfds, wfds, efds;
+  int pri, i, n, wfd, nfds;
+  char hisaddr[ADDRSZ];
+  struct sockaddr *sa = (struct sockaddr *)hisaddr;
+  struct sockaddr_in *sin = (struct sockaddr_in *)hisaddr;
+  struct timeval timeout, *tp;
+  int ssize = ADDRSZ;
+  const u_char *cp;
+  int tries;
+  int qlen;
+  int res;
+  struct tun_data tun;
+#define rbuff tun.data
+
+  if (mode & MODE_DIRECT) {
+    LogPrintf(LogDEBUG, "Opening modem\n");
+    if (OpenModem() < 0)
+      return;
+    LogPrintf(LogPHASE, "Packet mode enabled\n");
+    PacketMode(VarOpenMode);
+  } else if (mode & MODE_DEDICATED) {
+    if (modem < 0)
+      while (OpenModem() < 0)
+	nointr_sleep(VarReconnectTimer);
+  }
+  fflush(VarTerm);
+
+  timeout.tv_sec = 0;
+  timeout.tv_usec = 0;
+  reconnectState = RECON_UNKNOWN;
+
+  if (mode & MODE_BACKGROUND)
+    dial_up = 1;		/* Bring the line up */
+  else
+    dial_up = 0;		/* 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 = 1;
+
+    /*
+     * 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 && reconnectState == RECON_TRUE) {
+	if (++reconnectCount <= VarReconnectTries) {
+	  LogPrintf(LogPHASE, "Connection lost, re-establish (%d/%d)\n",
+		    reconnectCount, VarReconnectTries);
+	  StartRedialTimer(VarReconnectTimer);
+	  dial_up = 1;
+	} else {
+	  if (VarReconnectTries)
+	    LogPrintf(LogPHASE, "Connection lost, maximum (%d) times\n",
+		      VarReconnectTries);
+	  reconnectCount = 0;
+	  if (mode & MODE_BACKGROUND)
+	    Cleanup(EX_DEAD);
+	}
+	reconnectState = RECON_ENVOKED;
+      } else if (mode & MODE_DEDICATED)
+        PacketMode(VarOpenMode);
+    }
+
+    /*
+     * 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);
+      if (OpenModem() < 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 = 0;
+	  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) {
+	  ModemTimeout(NULL);
+	  PacketMode(VarOpenMode);
+	  dial_up = 0;
+	  reconnectState = RECON_UNKNOWN;
+	  tries = 0;
+	} else {
+	  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 = 0;
+	    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);
+    }
+
+#ifndef SIGALRM
+    /*
+     * *** IMPORTANT ***
+     * CPU is serviced every TICKUNIT micro seconds. This value must be chosen
+     * with great care. If this values is too big, it results in loss of
+     * characters from the modem and poor response.  If this value is too
+     * small, ppp eats too much CPU time.
+     */
+    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)) {
+      wfd = accept(server, sa, &ssize);
+      if (wfd < 0) {
+	LogPrintf(LogERROR, "DoLoop: accept(): %s\n", strerror(errno));
+	continue;
+      }
+      switch (sa->sa_family) {
+        case AF_LOCAL:
+          LogPrintf(LogPHASE, "Connected to local client.\n");
+          break;
+        case AF_INET:
+          if (ntohs(sin->sin_port) < 1024) {
+            LogPrintf(LogALERT, "Rejected client connection from %s:%u"
+                      "(invalid port number) !\n",
+                      inet_ntoa(sin->sin_addr), ntohs(sin->sin_port));
+	    close(wfd);
+	    continue;
+          }
+          LogPrintf(LogPHASE, "Connected to client from %s:%u\n",
+                    inet_ntoa(sin->sin_addr), sin->sin_port);
+          break;
+        default:
+	  write(wfd, "Unrecognised access !\n", 22);
+	  close(wfd);
+	  continue;
+      }
+      if (netfd >= 0) {
+	write(wfd, "Connection already in use.\n", 27);
+	close(wfd);
+	continue;
+      }
+      netfd = wfd;
+      VarTerm = fdopen(netfd, "a+");
+      LocalAuthInit();
+      IsInteractive(1);
+      Prompt();
+    }
+    if (netfd >= 0 && FD_ISSET(netfd, &rfds))
+      /* something to read from tty */
+      ReadTty();
+    if (modem >= 0 && FD_ISSET(modem, &wfds)) {
+      /* ready to write into modem */
+      ModemStartOutput(modem);
+      if (modem < 0)
+        dial_up = 1;
+    }
+    if (modem >= 0 && FD_ISSET(modem, &rfds)) {
+      /* something to read from modem */
+      if (LcpFsm.state <= ST_CLOSED)
+	nointr_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(0);
+	  } 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, &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 *) 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;
+
+#ifndef NOALIAS
+	    if (mode & MODE_ALIAS) {
+	      VarPacketAliasIn(rbuff, sizeof rbuff);
+	      n = ntohs(((struct ip *) rbuff)->ip_len);
+	    }
+#endif
+	    bp = mballoc(n, MB_IPIN);
+	    memcpy(MBUF_CTOP(bp), rbuff, 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)) >= 0)
+        dial_up = 1;
+
+      pri = PacketCheck(rbuff, n, FL_OUT);
+      if (pri >= 0) {
+#ifndef NOALIAS
+	if (mode & MODE_ALIAS) {
+	  VarPacketAliasOut(rbuff, sizeof rbuff);
+	  n = ntohs(((struct ip *) rbuff)->ip_len);
+	}
+#endif
+	IpEnqueue(pri, rbuff, n);
+      }
+    }
+  }
+  LogPrintf(LogDEBUG, "Job (DoLoop) done.\n");
+}