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