source/nmbd/nmbd.c

   1 /*
   2    Unix SMB/Netbios implementation.
   3    Version 1.9.
   4    NBT netbios routines and daemon - version 2
   5    Copyright (C) Andrew Tridgell 1994-1995
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 2 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program; if not, write to the Free Software
  19    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  20
  21    Revision History:
  22
  23    14 jan 96: lkcl@pires.co.uk
  24    added multiple workgroup domain master support
  25
  26 */
  27
  28 #include "includes.h"
  29
  30 extern int DEBUGLEVEL;
  31
  32 extern pstring debugf;
  33 pstring servicesf = CONFIGFILE;
  34
  35 extern pstring scope;
  36
  37 int ClientNMB   = -1;
  38 int ClientDGRAM = -1;
  39
  40 extern pstring myhostname;
  41 static pstring host_file;
  42 extern pstring myname;
  43
  44 /* are we running as a daemon ? */
  45 static BOOL is_daemon = False;
  46
  47 /* what server type are we currently */
  48
  49 time_t StartupTime =0;
  50
  51 extern struct in_addr ipzero;
  52
  53  /****************************************************************************
  54   catch a sigterm
  55   ****************************************************************************/
  56 static int sig_term()
  57 {
  58   BlockSignals(True,SIGTERM);
  59
  60   DEBUG(0,("Got SIGTERM: going down...\n"));
  61
  62   /* write out wins.dat file if samba is a WINS server */
  63   dump_names();
  64
  65   /* remove all samba names, with wins server if necessary. */
  66   remove_my_names();
  67
  68   /* announce all server entries as 0 time-to-live, 0 type */
  69   /* XXXX don't care if we never receive a response back... yet */
  70   remove_my_servers();
  71
  72   /* XXXX other things: if we are a master browser, force an election? */
  73
  74   exit(0);
  75 }
  76
  77
  78 /****************************************************************************
  79 catch a sighup
  80 ****************************************************************************/
  81 static int sig_hup(void)
  82 {
  83   BlockSignals(True,SIGHUP);
  84
  85   DEBUG(0,("Got SIGHUP (reload not implemented)\n"));
  86   dump_names();
  87   reload_services(True);
  88
  89   set_samba_nb_type();
  90
  91   BlockSignals(False,SIGHUP);
  92 #ifndef DONT_REINSTALL_SIG
  93   signal(SIGHUP,SIGNAL_CAST sig_hup);
  94 #endif
  95   return(0);
  96 }
  97
  98 /****************************************************************************
  99 catch a sigpipe
 100 ****************************************************************************/
 101 static int sig_pipe(void)
 102 {
 103   BlockSignals(True,SIGPIPE);
 104
 105   DEBUG(0,("Got SIGPIPE\n"));
 106   if (!is_daemon)
 107     exit(1);
 108   BlockSignals(False,SIGPIPE);
 109   return(0);
 110 }
 111
 112 #if DUMP_CORE
 113 /*******************************************************************
 114 prepare to dump a core file - carefully!
 115 ********************************************************************/
 116 static BOOL dump_core(void)
 117 {
 118   char *p;
 119   pstring dname;
 120   strcpy(dname,debugf);
 121   if ((p=strrchr(dname,'/'))) *p=0;
 122   strcat(dname,"/corefiles");
 123   mkdir(dname,0700);
 124   sys_chown(dname,getuid(),getgid());
 125   chmod(dname,0700);
 126   if (chdir(dname)) return(False);
 127   umask(~(0700));
 128
 129 #ifndef NO_GETRLIMIT
 130 #ifdef RLIMIT_CORE
 131   {
 132     struct rlimit rlp;
 133     getrlimit(RLIMIT_CORE, &rlp);
 134     rlp.rlim_cur = MAX(4*1024*1024,rlp.rlim_cur);
 135     setrlimit(RLIMIT_CORE, &rlp);
 136     getrlimit(RLIMIT_CORE, &rlp);
 137     DEBUG(3,("Core limits now %d %d\n",rlp.rlim_cur,rlp.rlim_max));
 138   }
 139 #endif
 140 #endif
 141
 142
 143   DEBUG(0,("Dumping core in %s\n",dname));
 144   return(True);
 145 }
 146 #endif
 147
 148
 149 /****************************************************************************
 150 possibly continue after a fault
 151 ****************************************************************************/
 152 static void fault_continue(void)
 153 {
 154 #if DUMP_CORE
 155   dump_core();
 156 #endif
 157 }
 158
 159 /*******************************************************************
 160   expire old names from the namelist and server list
 161   ******************************************************************/
 162 static void expire_names_and_servers(time_t t)
 163 {
 164   static time_t lastrun = 0;
 165
 166   if (!lastrun) lastrun = t;
 167   if (t < lastrun + 5) return;
 168   lastrun = t;
 169
 170   expire_names(t);
 171   expire_servers(t);
 172 }
 173
 174 /*****************************************************************************
 175   reload the services file
 176   **************************************************************************/
 177 BOOL reload_services(BOOL test)
 178 {
 179   BOOL ret;
 180   extern fstring remote_machine;
 181
 182   strcpy(remote_machine,"nmbd");
 183
 184   if (lp_loaded())
 185     {
 186       pstring fname;
 187       strcpy(fname,lp_configfile());
 188       if (file_exist(fname,NULL) && !strcsequal(fname,servicesf))
 189         {
 190           strcpy(servicesf,fname);
 191           test = False;
 192         }
 193     }
 194
 195   if (test && !lp_file_list_changed())
 196     return(True);
 197
 198   ret = lp_load(servicesf,True);
 199
 200   /* perhaps the config filename is now set */
 201   if (!test) {
 202     DEBUG(3,("services not loaded\n"));
 203     reload_services(True);
 204   }
 205
 206   load_interfaces();
 207   add_subnet_interfaces();
 208
 209   return(ret);
 210 }
 211
 212
 213
 214 /****************************************************************************
 215 load a netbios hosts file
 216 ****************************************************************************/
 217 static void load_hosts_file(char *fname)
 218 {
 219   FILE *f = fopen(fname,"r");
 220   pstring line;
 221   if (!f) {
 222     DEBUG(2,("Can't open lmhosts file %s\n",fname));
 223     return;
 224   }
 225
 226   while (!feof(f))
 227     {
 228       pstring ip,name,flags,extra;
 229       struct subnet_record *d;
 230       char *ptr;
 231       int count = 0;
 232       struct in_addr ipaddr;
 233       enum name_source source = LMHOSTS;
 234
 235       if (!fgets_slash(line,sizeof(pstring),f)) continue;
 236
 237       if (*line == '#') continue;
 238
 239       strcpy(ip,"");
 240       strcpy(name,"");
 241       strcpy(flags,"");
 242
 243       ptr = line;
 244
 245       if (next_token(&ptr,ip   ,NULL)) ++count;
 246       if (next_token(&ptr,name ,NULL)) ++count;
 247       if (next_token(&ptr,flags,NULL)) ++count;
 248       if (next_token(&ptr,extra,NULL)) ++count;
 249
 250       if (count <= 0) continue;
 251
 252       if (count > 0 && count < 2) {
 253         DEBUG(0,("Ill formed hosts line [%s]\n",line));
 254         continue;
 255       }
 256
 257       if (count >= 4) {
 258         DEBUG(0,("too many columns in %s (obsolete syntax)\n",fname));
 259         continue;
 260       }
 261
 262       DEBUG(4, ("lmhost entry: %s %s %s\n", ip, name, flags));
 263
 264       if (strchr(flags,'G') || strchr(flags,'S')) {
 265         DEBUG(0,("group flag in %s ignored (obsolete)\n",fname));
 266         continue;
 267       }
 268
 269       if (strchr(flags,'M')) {
 270         source = SELF;
 271         strcpy(myname,name);
 272       }
 273
 274       ipaddr = *interpret_addr2(ip);
 275       d = find_subnet_all(ipaddr);
 276       if (d) {
 277         add_netbios_entry(d,name,0x00,NB_ACTIVE,0,source,ipaddr,True,True);
 278         add_netbios_entry(d,name,0x20,NB_ACTIVE,0,source,ipaddr,True,True);
 279       }
 280     }
 281
 282   fclose(f);
 283 }
 284
 285
 286 /****************************************************************************
 287   The main select loop.
 288   ***************************************************************************/
 289 static void process(void)
 290 {
 291   BOOL run_election;
 292
 293   while (True)
 294     {
 295       time_t t = time(NULL);
 296       run_election = check_elections();
 297       listen_for_packets(run_election);
 298
 299       run_packet_queue();
 300       run_elections(t);
 301
 302       announce_host(t);
 303       announce_master(t);
 304       announce_remote(t);
 305
 306       query_refresh_names(t);
 307
 308       expire_names_and_servers(t);
 309       expire_netbios_response_entries(t);
 310       refresh_my_names(t);
 311
 312       write_browse_list(t);
 313       do_browser_lists(t);
 314       check_master_browser(t);
 315       add_domain_names(t);
 316     }
 317 }
 318
 319
 320 /****************************************************************************
 321   open the socket communication
 322 ****************************************************************************/
 323 static BOOL open_sockets(BOOL isdaemon, int port)
 324 {
 325   struct hostent *hp;
 326
 327   /* get host info */
 328   if ((hp = Get_Hostbyname(myhostname)) == 0) {
 329     DEBUG(0,( "Get_Hostbyname: Unknown host. %s\n",myhostname));
 330     return False;
 331   }
 332
 333   if (isdaemon)
 334     ClientNMB = open_socket_in(SOCK_DGRAM, port,0,interpret_addr(lp_socket_address()));
 335   else
 336     ClientNMB = 0;
 337
 338   ClientDGRAM = open_socket_in(SOCK_DGRAM,DGRAM_PORT,3,interpret_addr(lp_socket_address()));
 339
 340   if (ClientNMB == -1)
 341     return(False);
 342
 343   signal(SIGPIPE, SIGNAL_CAST sig_pipe);
 344
 345   set_socket_options(ClientNMB,"SO_BROADCAST");
 346   set_socket_options(ClientDGRAM,"SO_BROADCAST");
 347
 348   DEBUG(3,("Sockets opened.\n"));
 349   return True;
 350 }
 351
 352
 353 /****************************************************************************
 354   initialise connect, service and file structs
 355 ****************************************************************************/
 356 static BOOL init_structs()
 357 {
 358   extern fstring local_machine;
 359   char *p;
 360
 361   if (! *myname) {
 362     strcpy(myname,myhostname);
 363     p = strchr(myname,'.');
 364     if (p) *p = 0;
 365   }
 366   strupper(myname);
 367
 368   strcpy(local_machine,myname);
 369   trim_string(local_machine," "," ");
 370   p = strchr(local_machine,' ');
 371   if (p) *p = 0;
 372   strlower(local_machine);
 373
 374   return True;
 375 }
 376
 377 /****************************************************************************
 378 usage on the program
 379 ****************************************************************************/
 380 static void usage(char *pname)
 381 {
 382   DEBUG(0,("Incorrect program usage - is the command line correct?\n"));
 383
 384   printf("Usage: %s [-n name] [-D] [-p port] [-d debuglevel] [-l log basename]\n",pname);
 385   printf("Version %s\n",VERSION);
 386   printf("\t-D                    become a daemon\n");
 387   printf("\t-p port               listen on the specified port\n");
 388   printf("\t-d debuglevel         set the debuglevel\n");
 389   printf("\t-l log basename.      Basename for log/debug files\n");
 390   printf("\t-n netbiosname.       the netbios name to advertise for this host\n");
 391   printf("\t-H hosts file        load a netbios hosts file\n");
 392   printf("\n");
 393 }
 394
 395
 396 /****************************************************************************
 397   main program
 398   **************************************************************************/
 399  int main(int argc,char *argv[])
 400 {
 401   int port = NMB_PORT;
 402   int opt;
 403   extern FILE *dbf;
 404   extern char *optarg;
 405   char pidFile[100] = { 0 };
 406
 407   *host_file = 0;
 408
 409   StartupTime = time(NULL);
 410
 411   TimeInit();
 412
 413   strcpy(debugf,NMBLOGFILE);
 414
 415   setup_logging(argv[0],False);
 416
 417   charset_initialise();
 418
 419 #ifdef LMHOSTSFILE
 420   strcpy(host_file,LMHOSTSFILE);
 421 #endif
 422
 423   /* this is for people who can't start the program correctly */
 424   while (argc > 1 && (*argv[1] != '-')) {
 425     argv++;
 426     argc--;
 427   }
 428
 429   fault_setup(fault_continue);
 430
 431   signal(SIGHUP ,SIGNAL_CAST sig_hup);
 432   signal(SIGTERM,SIGNAL_CAST sig_term);
 433
 434   while ((opt = getopt(argc, argv, "s:T:I:C:bAi:B:N:Rn:l:d:Dp:hSH:G:f:")) != EOF)
 435     {
 436       switch (opt)
 437         {
 438         case 'f':
 439           strncpy(pidFile, optarg, sizeof(pidFile));
 440           break;
 441         case 's':
 442           strcpy(servicesf,optarg);
 443           break;
 444         case 'N':
 445         case 'B':
 446         case 'I':
 447         case 'C':
 448         case 'G':
 449           DEBUG(0,("Obsolete option '%c' used\n",opt));
 450           break;
 451         case 'H':
 452           strcpy(host_file,optarg);
 453           break;
 454         case 'n':
 455           strcpy(myname,optarg);
 456           strupper(myname);
 457           break;
 458         case 'l':
 459           sprintf(debugf,"%s.nmb",optarg);
 460           break;
 461         case 'i':
 462           strcpy(scope,optarg);
 463           strupper(scope);
 464           break;
 465         case 'D':
 466           is_daemon = True;
 467           break;
 468         case 'd':
 469           DEBUGLEVEL = atoi(optarg);
 470           break;
 471         case 'p':
 472           port = atoi(optarg);
 473           break;
 474         case 'h':
 475           usage(argv[0]);
 476           exit(0);
 477           break;
 478         default:
 479           if (!is_a_socket(0)) {
 480             usage(argv[0]);
 481           }
 482           break;
 483         }
 484     }
 485
 486   DEBUG(1,("%s netbios nameserver version %s started\n",timestring(),VERSION));
 487   DEBUG(1,("Copyright Andrew Tridgell 1994\n"));
 488
 489   get_myname(myhostname,NULL);
 490
 491   if (!reload_services(False))
 492     return(-1);
 493
 494   init_structs();
 495
 496   reload_services(True);
 497
 498   set_samba_nb_type();
 499
 500   if (!is_daemon && !is_a_socket(0)) {
 501     DEBUG(0,("standard input is not a socket, assuming -D option\n"));
 502     is_daemon = True;
 503   }
 504
 505   if (is_daemon) {
 506     DEBUG(2,("%s becoming a daemon\n",timestring()));
 507     become_daemon();
 508   }
 509
 510   if (*pidFile)
 511     {
 512       int     fd;
 513       char    buf[20];
 514
 515       if ((fd = open(pidFile,
 516         O_NONBLOCK | O_CREAT | O_WRONLY | O_TRUNC, 0644)) < 0)
 517         {
 518           DEBUG(0,("ERROR: can't open %s: %s\n", pidFile, strerror(errno)));
 519           exit(1);
 520         }
 521       if (fcntl_lock(fd,F_SETLK,0,1,F_WRLCK)==False)
 522         {
 523           DEBUG(0,("ERROR: nmbd is already running\n"));
 524           exit(1);
 525         }
 526       sprintf(buf, "%u\n", (unsigned int) getpid());
 527       if (write(fd, buf, strlen(buf)) < 0)
 528         {
 529           DEBUG(0,("ERROR: can't write to %s: %s\n", pidFile, strerror(errno)));
 530           exit(1);
 531         }
 532       /* Leave pid file open & locked for the duration... */
 533     }
 534
 535
 536   DEBUG(3,("Opening sockets %d\n", port));
 537
 538   if (!open_sockets(is_daemon,port)) return 1;
 539
 540   if (*host_file) {
 541     load_hosts_file(host_file);
 542     DEBUG(3,("Loaded hosts file\n"));
 543   }
 544
 545   add_my_names();
 546
 547   if (strequal(lp_workgroup(),"*")) {
 548     DEBUG(0,("ERROR: a workgroup name of * is no longer supported\n"));
 549   }
 550
 551   add_my_subnets(lp_workgroup());
 552
 553   DEBUG(3,("Checked names\n"));
 554
 555   load_netbios_names();
 556
 557   DEBUG(3,("Loaded names\n"));
 558
 559   write_browse_list(time(NULL));
 560
 561   DEBUG(3,("Dumped names\n"));
 562
 563   process();
 564   close_sockets();
 565
 566   if (dbf)
 567     fclose(dbf);
 568   return(0);
 569 }