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 1994-1997
   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 int global_nmb_port = -1;
  40
  41 extern pstring myhostname;
  42 static pstring host_file;
  43 extern pstring myname;
  44 extern fstring myworkgroup;
  45 extern char **my_netbios_names;
  46
  47 /* are we running as a daemon ? */
  48 static BOOL is_daemon = False;
  49
  50 /* what server type are we currently */
  51
  52 time_t StartupTime =0;
  53
  54 extern struct in_addr ipzero;
  55
  56  /****************************************************************************
  57   catch a sigterm
  58   ****************************************************************************/
  59 static int sig_term()
  60 {
  61   BlockSignals(True,SIGTERM);
  62
  63   DEBUG(0,("Got SIGTERM: going down...\n"));
  64
  65   /* write out wins.dat file if samba is a WINS server */
  66   dump_names();
  67
  68   /* remove all samba names, with wins server if necessary. */
  69   remove_my_names();
  70
  71   /* announce all server entries as 0 time-to-live, 0 type */
  72   /* XXXX don't care if we never receive a response back... yet */
  73   announce_my_servers_removed();
  74
  75   /* XXXX other things: if we are a master browser, force an election? */
  76
  77   exit(0);
  78   /* Keep compiler happy.. */
  79   return 0;
  80 }
  81
  82
  83 /****************************************************************************
  84 catch a sighup
  85 ****************************************************************************/
  86 static int sig_hup(void)
  87 {
  88   BlockSignals(True,SIGHUP);
  89
  90   DEBUG(0,("Got SIGHUP (reload not implemented)\n"));
  91   dump_names();
  92   reload_services(True);
  93
  94   set_samba_nb_type();
  95
  96   BlockSignals(False,SIGHUP);
  97 #ifndef DONT_REINSTALL_SIG
  98   signal(SIGHUP,SIGNAL_CAST sig_hup);
  99 #endif
 100   return(0);
 101 }
 102
 103 /****************************************************************************
 104 catch a sigpipe
 105 ****************************************************************************/
 106 static int sig_pipe(void)
 107 {
 108   BlockSignals(True,SIGPIPE);
 109
 110   DEBUG(0,("Got SIGPIPE\n"));
 111   if (!is_daemon)
 112     exit(1);
 113   BlockSignals(False,SIGPIPE);
 114   return(0);
 115 }
 116
 117 #if DUMP_CORE
 118 /*******************************************************************
 119 prepare to dump a core file - carefully!
 120 ********************************************************************/
 121 static BOOL dump_core(void)
 122 {
 123   char *p;
 124   pstring dname;
 125   pstrcpy(dname,debugf);
 126   if ((p=strrchr(dname,'/'))) *p=0;
 127   strcat(dname,"/corefiles");
 128   mkdir(dname,0700);
 129   sys_chown(dname,getuid(),getgid());
 130   chmod(dname,0700);
 131   if (chdir(dname)) return(False);
 132   umask(~(0700));
 133
 134 #ifndef NO_GETRLIMIT
 135 #ifdef RLIMIT_CORE
 136   {
 137     struct rlimit rlp;
 138     getrlimit(RLIMIT_CORE, &rlp);
 139     rlp.rlim_cur = MAX(4*1024*1024,rlp.rlim_cur);
 140     setrlimit(RLIMIT_CORE, &rlp);
 141     getrlimit(RLIMIT_CORE, &rlp);
 142     DEBUG(3,("Core limits now %d %d\n",rlp.rlim_cur,rlp.rlim_max));
 143   }
 144 #endif
 145 #endif
 146
 147
 148   DEBUG(0,("Dumping core in %s\n",dname));
 149   return(True);
 150 }
 151 #endif
 152
 153
 154 /****************************************************************************
 155 possibly continue after a fault
 156 ****************************************************************************/
 157 static void fault_continue(void)
 158 {
 159 #if DUMP_CORE
 160   dump_core();
 161 #endif
 162 }
 163
 164 /*******************************************************************
 165   expire old names from the namelist and server list
 166   ******************************************************************/
 167 static void expire_names_and_servers(time_t t)
 168 {
 169   static time_t lastrun = 0;
 170
 171   if (!lastrun) lastrun = t;
 172   if (t < lastrun + 5) return;
 173   lastrun = t;
 174
 175   expire_names(t);
 176   expire_servers(t);
 177 }
 178
 179 /*****************************************************************************
 180   reload the services file
 181   **************************************************************************/
 182 BOOL reload_services(BOOL test)
 183 {
 184   BOOL ret;
 185   extern fstring remote_machine;
 186
 187   strcpy(remote_machine,"nmbd");
 188
 189   if (lp_loaded())
 190     {
 191       pstring fname;
 192       pstrcpy(fname,lp_configfile());
 193       if (file_exist(fname,NULL) && !strcsequal(fname,servicesf))
 194         {
 195           pstrcpy(servicesf,fname);
 196           test = False;
 197         }
 198     }
 199
 200   if (test && !lp_file_list_changed())
 201     return(True);
 202
 203   ret = lp_load(servicesf,True);
 204
 205   /* perhaps the config filename is now set */
 206   if (!test) {
 207     DEBUG(3,("services not loaded\n"));
 208     reload_services(True);
 209   }
 210
 211   /* Do a sanity check for a misconfigured nmbd */
 212   if(lp_wins_support() && *lp_wins_server()) {
 213     DEBUG(0,("ERROR: both 'wins support = true' and 'wins server = <server>' \
 214 cannot be set in the smb.conf file. nmbd aborting.\n"));
 215     exit(10);
 216   }
 217
 218   return(ret);
 219 }
 220
 221
 222
 223 /****************************************************************************
 224 load a netbios hosts file
 225 ****************************************************************************/
 226 static void load_hosts_file(char *fname)
 227 {
 228   FILE *f = fopen(fname,"r");
 229   pstring line;
 230   if (!f) {
 231     DEBUG(2,("Can't open lmhosts file %s\n",fname));
 232     return;
 233   }
 234
 235   while (!feof(f))
 236     {
 237       pstring ip,name,flags,extra;
 238       struct subnet_record *d;
 239       char *ptr;
 240       int count = 0;
 241       struct in_addr ipaddr;
 242       enum name_source source = LMHOSTS;
 243
 244       if (!fgets_slash(line,sizeof(pstring),f)) continue;
 245
 246       if (*line == '#') continue;
 247
 248       strcpy(ip,"");
 249       strcpy(name,"");
 250       strcpy(flags,"");
 251
 252       ptr = line;
 253
 254       if (next_token(&ptr,ip   ,NULL)) ++count;
 255       if (next_token(&ptr,name ,NULL)) ++count;
 256       if (next_token(&ptr,flags,NULL)) ++count;
 257       if (next_token(&ptr,extra,NULL)) ++count;
 258
 259       if (count <= 0) continue;
 260
 261       if (count > 0 && count < 2) {
 262         DEBUG(0,("Ill formed hosts line [%s]\n",line));
 263         continue;
 264       }
 265
 266       if (count >= 4) {
 267         DEBUG(0,("too many columns in %s (obsolete syntax)\n",fname));
 268         continue;
 269       }
 270
 271       DEBUG(4, ("lmhost entry: %s %s %s\n", ip, name, flags));
 272
 273       if (strchr(flags,'G') || strchr(flags,'S')) {
 274         DEBUG(0,("group flag in %s ignored (obsolete)\n",fname));
 275         continue;
 276       }
 277
 278       if (strchr(flags,'M')) {
 279         source = SELF;
 280         pstrcpy(myname,name);
 281       }
 282
 283       ipaddr = *interpret_addr2(ip);
 284       d = find_subnet_all(ipaddr);
 285       if (d) {
 286         add_netbios_entry(d,name,0x00,NB_ACTIVE,0,source,ipaddr,True);
 287         add_netbios_entry(d,name,0x20,NB_ACTIVE,0,source,ipaddr,True);
 288       }
 289     }
 290
 291   fclose(f);
 292 }
 293
 294
 295 /****************************************************************************
 296   The main select loop.
 297   ***************************************************************************/
 298 static void process(void)
 299 {
 300   BOOL run_election;
 301
 302   while (True)
 303     {
 304       time_t t = time(NULL);
 305       run_election = check_elections();
 306       if(listen_for_packets(run_election))
 307         return;
 308
 309       run_packet_queue();
 310       run_elections(t);
 311
 312       announce_host(t);
 313       announce_master(t);
 314       announce_remote(t);
 315
 316       query_refresh_names(t);
 317
 318       expire_names_and_servers(t);
 319       expire_netbios_response_entries(t);
 320       refresh_my_names(t);
 321
 322       write_browse_list(t);
 323       do_browser_lists(t);
 324       check_master_browser(t);
 325       add_domain_names(t);
 326     }
 327 }
 328
 329
 330 /****************************************************************************
 331   open the socket communication
 332 ****************************************************************************/
 333 static BOOL open_sockets(BOOL isdaemon, int port)
 334 {
 335   /* The sockets opened here will be used to receive broadcast
 336      packets *only*. Interface specific sockets are opened in
 337      make_subnet() in namedbsubnet.c. Thus we bind to the
 338      address "0.0.0.0". The parameter 'socket address' is
 339      now deprecated.
 340    */
 341
 342   if (isdaemon)
 343     ClientNMB = open_socket_in(SOCK_DGRAM, port,0,0);
 344   else
 345     ClientNMB = 0;
 346
 347   ClientDGRAM = open_socket_in(SOCK_DGRAM,DGRAM_PORT,3,0);
 348
 349   if (ClientNMB == -1)
 350     return(False);
 351
 352   signal(SIGPIPE, SIGNAL_CAST sig_pipe);
 353
 354   set_socket_options(ClientNMB,"SO_BROADCAST");
 355   set_socket_options(ClientDGRAM,"SO_BROADCAST");
 356
 357   DEBUG(3,("open_sockets: Broadcast sockets opened.\n"));
 358   return True;
 359 }
 360
 361
 362 /****************************************************************************
 363   initialise connect, service and file structs
 364 ****************************************************************************/
 365 static BOOL init_structs()
 366 {
 367   extern fstring local_machine;
 368   char *p, *ptr;
 369   int namecount;
 370   int n;
 371   int nodup;
 372   pstring nbname;
 373
 374   if (! *myname) {
 375     fstrcpy(myname,myhostname);
 376     p = strchr(myname,'.');
 377     if (p) *p = 0;
 378   }
 379   strupper(myname);
 380
 381   /* Add any NETBIOS name aliases. Ensure that the first entry
 382      is equal to myname. */
 383   /* Work out the max number of netbios aliases that we have */
 384   ptr=lp_netbios_aliases();
 385   for (namecount=0; next_token(&ptr,nbname,NULL); namecount++)
 386     ;
 387   if (*myname)
 388       namecount++;
 389
 390   /* Allocate space for the netbios aliases */
 391   if((my_netbios_names=(char **)malloc(sizeof(char *)*(namecount+1))) == NULL)
 392   {
 393      DEBUG(0,("init_structs: malloc fail.\n"));
 394      return False;
 395   }
 396
 397   /* Use the myname string first */
 398   namecount=0;
 399   if (*myname)
 400     my_netbios_names[namecount++] = myname;
 401
 402   ptr=lp_netbios_aliases();
 403   while (next_token(&ptr,nbname,NULL)) {
 404     strupper(nbname);
 405     /* Look for duplicates */
 406     nodup=1;
 407     for(n=0; n<namecount; n++) {
 408       if (strcmp(nbname, my_netbios_names[n])==0)
 409         nodup=0;
 410     }
 411     if (nodup)
 412       my_netbios_names[namecount++]=strdup(nbname);
 413   }
 414
 415   /* Check the strdups succeeded. */
 416   for(n = 0; n < namecount; n++)
 417     if(my_netbios_names[n]==NULL)
 418     {
 419       DEBUG(0,("init_structs: malloc fail when allocating names.\n"));
 420       return False;
 421     }
 422
 423   /* Terminate name list */
 424   my_netbios_names[namecount++]=NULL;
 425
 426   fstrcpy(local_machine,myname);
 427   trim_string(local_machine," "," ");
 428   p = strchr(local_machine,' ');
 429   if (p)
 430     *p = 0;
 431   strlower(local_machine);
 432
 433   DEBUG(5, ("Netbios name list:-\n"));
 434   for (n=0; my_netbios_names[n]; n++)
 435     DEBUG(5, ("my_netbios_names[%d]=\"%s\"\n", n, my_netbios_names[n]));
 436
 437   return True;
 438 }
 439
 440 /****************************************************************************
 441 usage on the program
 442 ****************************************************************************/
 443 static void usage(char *pname)
 444 {
 445   DEBUG(0,("Incorrect program usage - is the command line correct?\n"));
 446
 447   printf("Usage: %s [-n name] [-D] [-p port] [-d debuglevel] [-l log basename]\n",pname);
 448   printf("Version %s\n",VERSION);
 449   printf("\t-D                    become a daemon\n");
 450   printf("\t-p port               listen on the specified port\n");
 451   printf("\t-d debuglevel         set the debuglevel\n");
 452   printf("\t-l log basename.      Basename for log/debug files\n");
 453   printf("\t-n netbiosname.       the netbios name to advertise for this host\n");
 454   printf("\t-H hosts file        load a netbios hosts file\n");
 455   printf("\n");
 456 }
 457
 458
 459 /****************************************************************************
 460   main program
 461   **************************************************************************/
 462  int main(int argc,char *argv[])
 463 {
 464   int opt;
 465   extern FILE *dbf;
 466   extern char *optarg;
 467   char pidFile[100] = { 0 };
 468
 469   global_nmb_port = NMB_PORT;
 470   *host_file = 0;
 471
 472   StartupTime = time(NULL);
 473
 474   TimeInit();
 475
 476   strcpy(debugf,NMBLOGFILE);
 477
 478   setup_logging(argv[0],False);
 479
 480   charset_initialise();
 481
 482 #ifdef LMHOSTSFILE
 483   strcpy(host_file,LMHOSTSFILE);
 484 #endif
 485
 486   /* this is for people who can't start the program correctly */
 487   while (argc > 1 && (*argv[1] != '-')) {
 488     argv++;
 489     argc--;
 490   }
 491
 492   fault_setup(fault_continue);
 493
 494   signal(SIGHUP ,SIGNAL_CAST sig_hup);
 495   signal(SIGTERM,SIGNAL_CAST sig_term);
 496
 497   while ((opt = getopt(argc, argv, "as:T:I:C:bAi:B:N:Rn:l:d:Dp:hSH:G:f:")) != EOF)
 498     {
 499       switch (opt)
 500         {
 501         case 'f':
 502           strncpy(pidFile, optarg, sizeof(pidFile));
 503           break;
 504         case 's':
 505           pstrcpy(servicesf,optarg);
 506           break;
 507         case 'N':
 508         case 'B':
 509         case 'I':
 510         case 'C':
 511         case 'G':
 512           DEBUG(0,("Obsolete option '%c' used\n",opt));
 513           break;
 514         case 'H':
 515           pstrcpy(host_file,optarg);
 516           break;
 517         case 'n':
 518           pstrcpy(myname,optarg);
 519           strupper(myname);
 520           break;
 521         case 'l':
 522           sprintf(debugf,"%s.nmb",optarg);
 523           break;
 524         case 'i':
 525           pstrcpy(scope,optarg);
 526           strupper(scope);
 527           break;
 528         case 'a':
 529                 {
 530                         extern BOOL append_log;
 531                         append_log = !append_log;
 532                 }
 533                 break;
 534         case 'D':
 535           is_daemon = True;
 536           break;
 537         case 'd':
 538           DEBUGLEVEL = atoi(optarg);
 539           break;
 540         case 'p':
 541           global_nmb_port = atoi(optarg);
 542           break;
 543         case 'h':
 544           usage(argv[0]);
 545           exit(0);
 546           break;
 547         default:
 548           if (!is_a_socket(0)) {
 549             usage(argv[0]);
 550           }
 551           break;
 552         }
 553     }
 554
 555   DEBUG(1,("%s netbios nameserver version %s started\n",timestring(),VERSION));
 556   DEBUG(1,("Copyright Andrew Tridgell 1994-1997\n"));
 557
 558   if(!get_myname(myhostname,NULL))
 559   {
 560     DEBUG(0,("Unable to get my hostname - exiting.\n"));
 561     return -1;
 562   }
 563
 564 #ifndef SYNC_DNS
 565   start_async_dns();
 566 #endif
 567
 568   if (!reload_services(False))
 569     return(-1);
 570
 571   codepage_initialise(lp_client_code_page());
 572
 573   if(!init_structs())
 574     return -1;
 575
 576   reload_services(True);
 577
 578   pstrcpy(myworkgroup, lp_workgroup());
 579
 580   if (strequal(myworkgroup,"*")) {
 581     DEBUG(0,("ERROR: a workgroup name of * is no longer supported\n"));
 582     exit(1);
 583   }
 584
 585   set_samba_nb_type();
 586
 587   if (!is_daemon && !is_a_socket(0)) {
 588     DEBUG(0,("standard input is not a socket, assuming -D option\n"));
 589     is_daemon = True;
 590   }
 591
 592   if (is_daemon) {
 593     DEBUG(2,("%s becoming a daemon\n",timestring()));
 594     become_daemon();
 595   }
 596
 597   if (*pidFile)
 598     {
 599       int     fd;
 600       char    buf[20];
 601
 602       if ((fd = open(pidFile,
 603 #ifdef O_NONBLOCK
 604         O_NONBLOCK |
 605 #endif
 606         O_CREAT | O_WRONLY | O_TRUNC, 0644)) < 0)
 607         {
 608           DEBUG(0,("ERROR: can't open %s: %s\n", pidFile, strerror(errno)));
 609           exit(1);
 610         }
 611       if (fcntl_lock(fd,F_SETLK,0,1,F_WRLCK)==False)
 612         {
 613           DEBUG(0,("ERROR: nmbd is already running\n"));
 614           exit(1);
 615         }
 616       sprintf(buf, "%u\n", (unsigned int) getpid());
 617       if (write(fd, buf, strlen(buf)) < 0)
 618         {
 619           DEBUG(0,("ERROR: can't write to %s: %s\n", pidFile, strerror(errno)));
 620           exit(1);
 621         }
 622       /* Leave pid file open & locked for the duration... */
 623     }
 624
 625
 626   DEBUG(3,("Opening sockets %d\n", global_nmb_port));
 627
 628   if (!open_sockets(is_daemon,global_nmb_port)) return 1;
 629
 630   load_interfaces();
 631   add_my_subnets(myworkgroup);
 632
 633   add_my_names();
 634
 635   DEBUG(3,("Checked names\n"));
 636
 637   load_netbios_names();
 638
 639   DEBUG(3,("Loaded names\n"));
 640
 641   if (*host_file) {
 642     load_hosts_file(host_file);
 643     DEBUG(3,("Loaded hosts file\n"));
 644   }
 645
 646   write_browse_list(time(NULL));
 647
 648   DEBUG(3,("Dumped names\n"));
 649
 650   /* We can only take sigterm signals in the select. */
 651   BlockSignals(True,SIGTERM);
 652
 653   process();
 654   close_sockets();
 655
 656   if (dbf)
 657     fclose(dbf);
 658   return(0);
 659 }