/* 
   Unix SMB/Netbios implementation.
   Version 1.9.
   Main SMB server routines
   Copyright (C) Andrew Tridgell 1992-1998
   
   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2 of the License, or
   (at your option) any later version.
   
   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.
   
   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/

#include "includes.h"
#include "trans2.h"

pstring servicesf = CONFIGFILE;
extern pstring debugf;
extern pstring sesssetup_user;
extern fstring global_myworkgroup;
extern pstring global_myname;

char *InBuffer = NULL;
char *OutBuffer = NULL;
char *last_inbuf = NULL;

int am_parent = 1;

/* the last message the was processed */
int last_message = -1;

/* a useful macro to debug the last message processed */
#define LAST_MESSAGE() smb_fn_name(last_message)

extern pstring scope;
extern int DEBUGLEVEL;
extern int case_default;
extern BOOL case_sensitive;
extern BOOL case_preserve;
extern BOOL use_mangled_map;
extern BOOL short_case_preserve;
extern BOOL case_mangle;
time_t smb_last_time=(time_t)0;
extern BOOL global_machine_pasword_needs_changing;

extern int smb_read_error;

extern pstring user_socket_options;

#ifdef WITH_DFS
extern int dcelogin_atmost_once;
#endif /* WITH_DFS */

/*
 * This is set on startup - it defines the SID for this
 * machine.
 */
extern DOM_SID global_machine_sid;

/* 
 * Size of data we can send to client. Set
 *  by the client for all protocols above CORE.
 *  Set by us for CORE protocol.
 */
int max_send = BUFFER_SIZE;
/*
 * Size of the data we can receive. Set by us.
 * Can be modified by the max xmit parameter.
 */
int max_recv = BUFFER_SIZE;

/* Oplock ipc UDP socket. */
int oplock_sock = -1;
uint16 oplock_port = 0;
/* Current number of oplocks we have outstanding. */
int32 global_oplocks_open = 0;

BOOL global_oplock_break = False;

extern fstring remote_machine;

extern pstring OriginalDir;

/* these can be set by some functions to override the error codes */
int unix_ERR_class=SMB_SUCCESS;
int unix_ERR_code=0;


extern int extra_time_offset;

extern pstring myhostname;

/****************************************************************************
  when exiting, take the whole family
****************************************************************************/
void  *dflt_sig(void)
{
  exit_server("caught signal");
  return 0; /* Keep -Wall happy :-) */
}
/****************************************************************************
  Send a SIGTERM to our process group.
*****************************************************************************/
void  killkids(void)
{
  if(am_parent) kill(0,SIGTERM);
}



/****************************************************************************
  this is called when the client exits abruptly
  **************************************************************************/
static void sig_pipe(int sig)
{
	struct cli_state *cli;
	BlockSignals(True,SIGPIPE);

	if ((cli = server_client()) && cli->initialised) {
		DEBUG(3,("lost connection to password server\n"));
		cli_shutdown(cli);
		BlockSignals(False,SIGPIPE);
		return;
	}

	exit_server("Got sigpipe\n");
}

/****************************************************************************
  open the socket communication
****************************************************************************/
static BOOL open_sockets(BOOL is_daemon,int port)
{
  extern int Client;

  if (is_daemon)
  {
    int num_interfaces = iface_count();
    int fd_listenset[FD_SETSIZE];
    fd_set listen_set;
    int s;
    int i;

#ifdef HAVE_ATEXIT
    static int atexit_set;
    if(atexit_set == 0) {
	    atexit_set=1;
	    atexit(killkids);
    }
#endif

    /* Stop zombies */
    CatchChild();


    FD_ZERO(&listen_set);

    if(lp_interfaces() && lp_bind_interfaces_only())
    {
       /* We have been given an interfaces line, and been 
          told to only bind to those interfaces. Create a
          socket per interface and bind to only these.
        */

      if(num_interfaces > FD_SETSIZE)
      {
        DEBUG(0,("open_sockets: Too many interfaces specified to bind to. Number was %d \
max can be %d\n", num_interfaces, FD_SETSIZE));
        return False;
      }

      /* Now open a listen socket for each of the interfaces. */
      for(i = 0; i < num_interfaces; i++)
      {
        struct in_addr *ifip = iface_n_ip(i);

        if(ifip == NULL)
        {
          DEBUG(0,("open_sockets: interface %d has NULL IP address !\n", i));
          continue;
        }
        s = fd_listenset[i] = open_socket_in(SOCK_STREAM, port, 0, ifip->s_addr);
        if(s == -1)
          return False;
        /* ready to listen */
        if (listen(s, 5) == -1) 
        {
          DEBUG(0,("listen: %s\n",strerror(errno)));
          close(s);
          return False;
        }
        FD_SET(s,&listen_set);
      }
    }
    else
    {
      /* Just bind to 0.0.0.0 - accept connections from anywhere. */
      num_interfaces = 1;

      /* open an incoming socket */
      s = open_socket_in(SOCK_STREAM, port, 0,interpret_addr(lp_socket_address()));
      if (s == -1)
        return(False);

      /* ready to listen */
      if (listen(s, 5) == -1) 
      {
        DEBUG(0,("open_sockets: listen: %s\n",strerror(errno)));
        close(s);
        return False;
      }

      fd_listenset[0] = s;
      FD_SET(s,&listen_set);
    }      

    /* now accept incoming connections - forking a new process
       for each incoming connection */
    DEBUG(2,("waiting for a connection\n"));
    while (1)
    {
      fd_set lfds;
      int num;

      memcpy((char *)&lfds, (char *)&listen_set, sizeof(listen_set));

      num = sys_select(&lfds,NULL);

      if (num == -1 && errno == EINTR)
        continue;

      /* Find the sockets that are read-ready - accept on these. */
      for( ; num > 0; num--)
      {
        struct sockaddr addr;
        int in_addrlen = sizeof(addr);

        s = -1;
        for(i = 0; i < num_interfaces; i++)
        {
          if(FD_ISSET(fd_listenset[i],&lfds))
          {
            s = fd_listenset[i];
            /* Clear this so we don't look at it again. */
            FD_CLR(fd_listenset[i],&lfds);
            break;
          }
        }

        Client = accept(s,&addr,&in_addrlen);

        if (Client == -1 && errno == EINTR)
          continue;

        if (Client == -1)
        {
          DEBUG(0,("open_sockets: accept: %s\n",strerror(errno)));
          continue;
        }

        if (Client != -1 && fork()==0)
        {
          /* Child code ... */

          CatchSignal(SIGPIPE, SIGNAL_CAST sig_pipe);

          /* close the listening socket(s) */
          for(i = 0; i < num_interfaces; i++)
            close(fd_listenset[i]);

          /* close our standard file descriptors */
          close_low_fds();
          am_parent = 0;
  
          set_socket_options(Client,"SO_KEEPALIVE");
          set_socket_options(Client,user_socket_options);

          /* Reset global variables in util.c so that
             client substitutions will be done correctly
             in the process.
           */
          reset_globals_after_fork();
          return True; 
        }
        close(Client); /* The parent doesn't need this socket */

	/*
	 * Force parent to check log size after spawning child.
	 * Fix from klausr@ITAP.Physik.Uni-Stuttgart.De.
	 * The parent smbd will log to logserver.smb. 
	 * It writes only two messages for each child
	 * started/finished. But each child writes, say, 50 messages also in
	 * logserver.smb, begining with the debug_count of the parent, before the
	 * child opens its own log file logserver.client. In a worst case
	 * scenario the size of logserver.smb would be checked after about
	 * 50*50=2500 messages (ca. 100kb).
	 */
	force_check_log_size();
 
      } /* end for num */
    } /* end while 1 */
  } /* end if is_daemon */
  else
  {
    /* Started from inetd. fd 0 is the socket. */
    /* We will abort gracefully when the client or remote system 
       goes away */
    CatchSignal(SIGPIPE, SIGNAL_CAST sig_pipe);
    Client = dup(0);

    /* close our standard file descriptors */
    close_low_fds();

    set_socket_options(Client,"SO_KEEPALIVE");
    set_socket_options(Client,user_socket_options);
  }

  return True;
}

/****************************************************************************
  reload the services file
  **************************************************************************/
BOOL reload_services(BOOL test)
{
	BOOL ret;

	if (lp_loaded()) {
		pstring fname;
		pstrcpy(fname,lp_configfile());
		if (file_exist(fname,NULL) && !strcsequal(fname,servicesf)) {
			pstrcpy(servicesf,fname);
			test = False;
		}
	}

	reopen_logs();

	if (test && !lp_file_list_changed())
		return(True);

	lp_killunused(conn_snum_used);

	ret = lp_load(servicesf,False,False,True);

	load_printers();

	/* perhaps the config filename is now set */
	if (!test)
		reload_services(True);

	reopen_logs();

	load_interfaces();

	{
		extern int Client;
		if (Client != -1) {      
			set_socket_options(Client,"SO_KEEPALIVE");
			set_socket_options(Client,user_socket_options);
		}
	}

	reset_mangled_cache();

	/* this forces service parameters to be flushed */
	become_service(NULL,True);

	return(ret);
}



/****************************************************************************
this prevents zombie child processes
****************************************************************************/
BOOL reload_after_sighup = False;

static void sig_hup(int sig)
{
  BlockSignals(True,SIGHUP);
  DEBUG(0,("Got SIGHUP\n"));

  /*
   * Fix from <branko.cibej@hermes.si> here.
   * We used to reload in the signal handler - this
   * is a *BIG* no-no.
   */

  reload_after_sighup = True;
  BlockSignals(False,SIGHUP);
}



#if DUMP_CORE
/*******************************************************************
prepare to dump a core file - carefully!
********************************************************************/
static BOOL dump_core(void)
{
  char *p;
  pstring dname;
  pstrcpy(dname,debugf);
  if ((p=strrchr(dname,'/'))) *p=0;
  pstrcat(dname,"/corefiles");
  mkdir(dname,0700);
  sys_chown(dname,getuid(),getgid());
  chmod(dname,0700);
  if (chdir(dname)) return(False);
  umask(~(0700));

#ifdef HAVE_GETRLIMIT
#ifdef RLIMIT_CORE
  {
    struct rlimit rlp;
    getrlimit(RLIMIT_CORE, &rlp);
    rlp.rlim_cur = MAX(4*1024*1024,rlp.rlim_cur);
    setrlimit(RLIMIT_CORE, &rlp);
    getrlimit(RLIMIT_CORE, &rlp);
    DEBUG(3,("Core limits now %d %d\n",(int)rlp.rlim_cur,(int)rlp.rlim_max));
  }
#endif
#endif


  DEBUG(0,("Dumping core in %s\n",dname));
  abort();
  return(True);
}
#endif

/****************************************************************************
exit the server
****************************************************************************/
void exit_server(char *reason)
{
  static int firsttime=1;

  if (!firsttime) exit(0);
  firsttime = 0;

  unbecome_user();
  DEBUG(2,("Closing connections\n"));

  conn_close_all();

#ifdef WITH_DFS
  if (dcelogin_atmost_once) {
    dfs_unlogin();
  }
#endif
  if (!reason) {   
    int oldlevel = DEBUGLEVEL;
    DEBUGLEVEL = 10;
    DEBUG(0,("Last message was %s\n",smb_fn_name(last_message)));
    if (last_inbuf)
      show_msg(last_inbuf);
    DEBUGLEVEL = oldlevel;
    DEBUG(0,("===============================================================\n"));
#if DUMP_CORE
    if (dump_core()) return;
#endif
  }    

  locking_end();

  DEBUG( 3, ( "Server exit (%s)\n", (reason ? reason : "") ) );
  exit(0);
}



/****************************************************************************
  initialise connect, service and file structs
****************************************************************************/
static void init_structs(void )
{
  get_myname(myhostname,NULL);

  /*
   * Set the machine NETBIOS name if not already
   * set from the config file.
   */

  if (!*global_myname)
  {
    char *p;
    fstrcpy( global_myname, myhostname );
    p = strchr( global_myname, '.' );
    if (p) 
      *p = 0;
  }
  strupper( global_myname );

  conn_init();

  file_init();

  /* for RPC pipes */
  init_rpc_pipe_hnd();

  /* for LSA handles */
  init_lsa_policy_hnd();

  init_dptrs();
}

/****************************************************************************
usage on the program
****************************************************************************/
static void usage(char *pname)
{
  DEBUG(0,("Incorrect program usage - are you sure the command line is correct?\n"));

  printf("Usage: %s [-D] [-p port] [-d debuglevel] [-l log basename] [-s services file]\n",pname);
  printf("Version %s\n",VERSION);
  printf("\t-D                    become a daemon\n");
  printf("\t-p port               listen on the specified port\n");
  printf("\t-d debuglevel         set the debuglevel\n");
  printf("\t-l log basename.      Basename for log/debug files\n");
  printf("\t-s services file.     Filename of services file\n");
  printf("\t-P                    passive only\n");
  printf("\t-a                    overwrite log file, don't append\n");
  printf("\n");
}


/****************************************************************************
  main program
****************************************************************************/
 int main(int argc,char *argv[])
{
  extern BOOL append_log;
  /* shall I run as a daemon */
  BOOL is_daemon = False;
  int port = SMB_PORT;
  int opt;
  extern char *optarg;

#ifdef HAVE_SET_AUTH_PARAMETERS
  set_auth_parameters(argc,argv);
#endif

#ifdef HAVE_SETLUID
  /* needed for SecureWare on SCO */
  setluid(0);
#endif

  append_log = True;

  TimeInit();

  pstrcpy(debugf,SMBLOGFILE);  

  pstrcpy(remote_machine, "smb");

  setup_logging(argv[0],False);

  charset_initialise();

  /* make absolutely sure we run as root - to handle cases where people
     are crazy enough to have it setuid */
#ifdef HAVE_SETRESUID
  setresuid(0,0,0);
#else
  setuid(0);
  seteuid(0);
  setuid(0);
  seteuid(0);
#endif

  fault_setup((void (*)(void *))exit_server);
  CatchSignal(SIGTERM , SIGNAL_CAST dflt_sig);

  /* we want total control over the permissions on created files,
     so set our umask to 0 */
  umask(0);

  GetWd(OriginalDir);

  init_uid();

  /* this is for people who can't start the program correctly */
  while (argc > 1 && (*argv[1] != '-'))
    {
      argv++;
      argc--;
    }

  while ((opt = getopt(argc, argv, "O:i:l:s:d:Dp:hPaf:")) != EOF)
    switch (opt)
      {
      case 'O':
	pstrcpy(user_socket_options,optarg);
	break;
      case 'i':
	pstrcpy(scope,optarg);
	break;
      case 'P':
	{
	  extern BOOL passive;
	  passive = True;
	}
	break;	
      case 's':
	pstrcpy(servicesf,optarg);
	break;
      case 'l':
	pstrcpy(debugf,optarg);
	break;
      case 'a':
	{
	  extern BOOL append_log;
	  append_log = !append_log;
	}
	break;
      case 'D':
	is_daemon = True;
	break;
      case 'd':
	if (*optarg == 'A')
	  DEBUGLEVEL = 10000;
	else
	  DEBUGLEVEL = atoi(optarg);
	break;
      case 'p':
	port = atoi(optarg);
	break;
      case 'h':
	usage(argv[0]);
	exit(0);
	break;
      default:
	usage(argv[0]);
	exit(1);
      }

  reopen_logs();

  DEBUG( 1, ( "smbd version %s started.\n", VERSION ) );
  DEBUGADD( 1, ( "Copyright Andrew Tridgell 1992-1997\n" ) );

  DEBUG(2,("uid=%d gid=%d euid=%d egid=%d\n",
	(int)getuid(),(int)getgid(),(int)geteuid(),(int)getegid()));

  if (sizeof(uint16) < 2 || sizeof(uint32) < 4)
    {
      DEBUG(0,("ERROR: Samba is not configured correctly for the word size on your machine\n"));
      exit(1);
    }

  init_structs();

  if (!reload_services(False))
    return(-1);	

#ifdef WITH_SSL
  {
    extern BOOL sslEnabled;
    sslEnabled = lp_ssl_enabled();
    if(sslEnabled)
      sslutil_init(True);
  }
#endif        /* WITH_SSL */

  codepage_initialise(lp_client_code_page());

  pstrcpy(global_myworkgroup, lp_workgroup());

  if(!pdb_generate_machine_sid()) {
	  DEBUG(0,("ERROR: Samba cannot get a machine SID.\n"));
	  exit(1);
  }

  CatchSignal(SIGHUP,SIGNAL_CAST sig_hup);

  /* Setup the signals that allow the debug log level
     to by dynamically changed. */
 
  /* If we are using the malloc debug code we can't use
     SIGUSR1 and SIGUSR2 to do debug level changes. */

#ifndef MEM_MAN
#if defined(SIGUSR1)
  CatchSignal( SIGUSR1, SIGNAL_CAST sig_usr1 );
#endif /* SIGUSR1 */
   
#if defined(SIGUSR2)
  CatchSignal( SIGUSR2, SIGNAL_CAST sig_usr2 );
#endif /* SIGUSR2 */
#endif /* MEM_MAN */

  DEBUG( 3, ( "loaded services\n" ) );

  if (!is_daemon && !is_a_socket(0))
    {
      DEBUG(0,("standard input is not a socket, assuming -D option\n"));
      is_daemon = True;
    }

  if (is_daemon)
    {
      DEBUG( 3, ( "Becoming a daemon.\n" ) );
      become_daemon();
    }

  if (!directory_exist(lp_lockdir(), NULL)) {
	  mkdir(lp_lockdir(), 0755);
  }

  if (is_daemon) {
	  pidfile_create("smbd");
  }

  if (!open_sockets(is_daemon,port))
    exit(1);

  if (!locking_init(0))
    exit(1);

  if(!initialize_password_db())
    exit(1);

  /* possibly reload the services file. */
  reload_services(True);

  max_recv = MIN(lp_maxxmit(),BUFFER_SIZE);

  if (*lp_rootdir())
    {
      if (sys_chroot(lp_rootdir()) == 0)
	DEBUG( 2, ( "Changed root to %s\n", lp_rootdir() ) );
    }

  /* Setup the oplock IPC socket. */
  if( !open_oplock_ipc() )
    exit(1);

  smbd_process();
  close_sockets();

  exit_server("normal exit");
  return(0);
}