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