source/wrepld/server.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    Main SMB server routines
   4    Copyright (C) Jean François Micouleau      1998-2002.
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 2 of the License, or
   9    (at your option) any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program; if not, write to the Free Software
  18    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  19 */
  20
  21 #include "includes.h"
  22 #include "wins_repl.h"
  23
  24 extern pstring user_socket_options;
  25
  26 extern WINS_OWNER *global_wins_table;
  27 extern int partner_count;
  28
  29 extern fd_set *listen_set;
  30 extern int listen_number;
  31 extern int *sock_array;
  32
  33 extern TALLOC_CTX *mem_ctx;
  34
  35 int wins_port = 42;
  36
  37 /****************************************************************************
  38   when exiting, take the whole family
  39 ****************************************************************************/
  40 static void *dflt_sig(void)
  41 {
  42         exit_server("caught signal");
  43         return NULL;
  44 }
  45
  46 /****************************************************************************
  47   reload the services file
  48   **************************************************************************/
  49 BOOL reload_services(BOOL test)
  50 {
  51         BOOL ret;
  52
  53         if (lp_loaded()) {
  54                 pstring fname;
  55                 pstrcpy(fname,lp_configfile());
  56                 if (file_exist(fname,NULL) && !strcsequal(fname,dyn_CONFIGFILE)) {
  57                         pstrcpy(dyn_CONFIGFILE,fname);
  58                         test = False;
  59                 }
  60         }
  61
  62         reopen_logs();
  63
  64         if (test && !lp_file_list_changed())
  65                 return(True);
  66
  67         ret = lp_load(dyn_CONFIGFILE,False,False,True);
  68
  69
  70         /* perhaps the config filename is now set */
  71         if (!test)
  72                 reload_services(True);
  73
  74         reopen_logs();
  75
  76         load_interfaces();
  77
  78         return(ret);
  79 }
  80
  81 /****************************************************************************
  82  Catch a sighup.
  83 ****************************************************************************/
  84
  85 VOLATILE sig_atomic_t reload_after_sighup = False;
  86
  87 static void sig_hup(int sig)
  88 {
  89         BlockSignals(True,SIGHUP);
  90         DEBUG(0,("Got SIGHUP\n"));
  91
  92         sys_select_signal(SIGHUP);
  93         reload_after_sighup = True;
  94         BlockSignals(False,SIGHUP);
  95 }
  96
  97 #if DUMP_CORE
  98 /*******************************************************************
  99 prepare to dump a core file - carefully!
 100 ********************************************************************/
 101 static BOOL dump_core(void)
 102 {
 103         char *p;
 104         pstring dname;
 105         pstrcpy(dname,lp_logfile());
 106         if ((p=strrchr_m(dname,'/'))) *p=0;
 107         pstrcat(dname,"/corefiles");
 108         mkdir(dname,0700);
 109         sys_chown(dname,getuid(),getgid());
 110         chmod(dname,0700);
 111         if (chdir(dname)) return(False);
 112         umask(~(0700));
 113
 114 #ifdef HAVE_GETRLIMIT
 115 #ifdef RLIMIT_CORE
 116         {
 117                 struct rlimit rlp;
 118                 getrlimit(RLIMIT_CORE, &rlp);
 119                 rlp.rlim_cur = MAX(4*1024*1024,rlp.rlim_cur);
 120                 setrlimit(RLIMIT_CORE, &rlp);
 121                 getrlimit(RLIMIT_CORE, &rlp);
 122                 DEBUG(3,("Core limits now %d %d\n",
 123                          (int)rlp.rlim_cur,(int)rlp.rlim_max));
 124         }
 125 #endif
 126 #endif
 127
 128
 129         DEBUG(0,("Dumping core in %s\n",dname));
 130         abort();
 131         return(True);
 132 }
 133 #endif
 134
 135 /****************************************************************************
 136 exit the server
 137 ****************************************************************************/
 138 void exit_server(const char *reason)
 139 {
 140         static int firsttime=1;
 141
 142         if (!firsttime)
 143                 exit(0);
 144         firsttime = 0;
 145
 146         DEBUG(2,("Closing connections\n"));
 147
 148         if (!reason) {
 149                 int oldlevel = DEBUGLEVEL;
 150                 DEBUGLEVEL = 10;
 151                 DEBUGLEVEL = oldlevel;
 152                 DEBUG(0,("===============================================================\n"));
 153 #if DUMP_CORE
 154                 if (dump_core()) return;
 155 #endif
 156         }
 157
 158         DEBUG(3,("Server exit (%s)\n", (reason ? reason : "")));
 159         exit(0);
 160 }
 161
 162 /****************************************************************************
 163   Create an fd_set containing all the sockets in the subnet structures,
 164   plus the broadcast sockets.
 165 ***************************************************************************/
 166
 167 static BOOL create_listen_fdset( int *maxfd)
 168 {
 169         int i;
 170         int num_interfaces = iface_count();
 171         int s;
 172
 173         listen_set = (fd_set *)malloc(sizeof(fd_set));
 174         if(listen_set == NULL) {
 175                 DEBUG(0,("create_listen_fdset: malloc fail !\n"));
 176                 return True;
 177         }
 178
 179 #ifdef HAVE_ATEXIT
 180         {
 181                 static int atexit_set;
 182                 if(atexit_set == 0) {
 183                         atexit_set=1;
 184                 }
 185         }
 186 #endif
 187
 188         FD_ZERO(listen_set);
 189
 190         if(lp_interfaces() && lp_bind_interfaces_only()) {
 191                 /* We have been given an interfaces line, and been
 192                    told to only bind to those interfaces. Create a
 193                    socket per interface and bind to only these.
 194                 */
 195
 196                 if(num_interfaces > FD_SETSIZE) {
 197                         DEBUG(0,("create_listen_fdset: Too many interfaces specified to bind to. Number was %d max can be %d\n", num_interfaces, FD_SETSIZE));
 198                         return False;
 199                 }
 200
 201                 /* Now open a listen socket for each of the interfaces. */
 202                 for(i = 0; i < num_interfaces; i++) {
 203                         struct in_addr *ifip = iface_n_ip(i);
 204
 205                         if(ifip == NULL) {
 206                                 DEBUG(0,("create_listen_fdset: interface %d has NULL IP address !\n", i));
 207                                 continue;
 208                         }
 209                         s = open_socket_in(SOCK_STREAM, wins_port, 0, ifip->s_addr, True);
 210                         if(s == -1)
 211                                 return False;
 212
 213                         /* ready to listen */
 214                         set_socket_options(s,"SO_KEEPALIVE");
 215                         set_socket_options(s,user_socket_options);
 216
 217                         if (listen(s, 5) == -1) {
 218                                 DEBUG(5,("listen: %s\n",strerror(errno)));
 219                                 close(s);
 220                                 return False;
 221                         }
 222                         add_fd_to_sock_array(s);
 223                         FD_SET(s, listen_set);
 224                         *maxfd = MAX( *maxfd, s);
 225                 }
 226         } else {
 227                 /* Just bind to 0.0.0.0 - accept connections from anywhere. */
 228                 num_interfaces = 1;
 229
 230                 /* open an incoming socket */
 231                 s = open_socket_in(SOCK_STREAM, wins_port, 0, interpret_addr(lp_socket_address()),True);
 232                 if (s == -1)
 233                         return(False);
 234
 235                 /* ready to listen */
 236                 set_socket_options(s,"SO_KEEPALIVE");
 237                 set_socket_options(s,user_socket_options);
 238
 239                 if (listen(s, 5) == -1) {
 240                         DEBUG(0,("create_listen_fdset: listen: %s\n", strerror(errno)));
 241                         close(s);
 242                         return False;
 243                 }
 244
 245                 add_fd_to_sock_array(s);
 246                 FD_SET(s, listen_set);
 247                 *maxfd = MAX( *maxfd, s);
 248         }
 249
 250         return True;
 251 }
 252
 253 /*******************************************************************
 254   read a packet from a socket and parse it, returning a packet ready
 255   to be used or put on the queue. This assumes a UDP socket
 256   ******************************************************************/
 257 static struct wins_packet_struct *read_wins_packet(int fd, int timeout)
 258 {
 259         struct wins_packet_struct *p;
 260         GENERIC_PACKET *q;
 261         struct BUFFER inbuf;
 262         ssize_t len=0;
 263         size_t total=0;
 264         ssize_t ret;
 265         BOOL ok = False;
 266
 267         inbuf.buffer=NULL;
 268         inbuf.length=0;
 269         inbuf.offset=0;
 270
 271         if(!grow_buffer(&inbuf, 4))
 272                 return NULL;
 273
 274         ok = (read(fd, inbuf.buffer,4) == 4);
 275         if (!ok)
 276                 return NULL;
 277         len = smb_len(inbuf.buffer);
 278
 279         if (len<=0)
 280                 return NULL;
 281
 282         if(!grow_buffer(&inbuf, len))
 283                 return NULL;
 284
 285         while (total < len) {
 286                 ret = read(fd, inbuf.buffer + total + 4, len - total);
 287                 if (ret == 0) {
 288                         DEBUG(10,("read_socket_data: recv of %d returned 0. Error = %s\n", (int)(len - total), strerror(errno) ));
 289                         return NULL;
 290                 }
 291                 if (ret == -1) {
 292                         DEBUG(0,("read_socket_data: recv failure for %d. Error = %s\n", (int)(len - total), strerror(errno) ));
 293                         return NULL;
 294                 }
 295                 total += ret;
 296         }
 297
 298         q = talloc(mem_ctx, GENERIC_PACKET);
 299         p = talloc(mem_ctx, struct wins_packet_struct);
 300         if (q==NULL || p==NULL)
 301                 return NULL;
 302
 303         decode_generic_packet(&inbuf, q);
 304
 305         q->fd=fd;
 306
 307         p->next = NULL;
 308         p->prev = NULL;
 309         p->stop_packet = False;
 310         p->timestamp = time(NULL);
 311         p->fd = fd;
 312         p->packet=q;
 313
 314         return p;
 315 }
 316
 317 static struct wins_packet_struct *packet_queue = NULL;
 318
 319 /*******************************************************************
 320   Queue a packet into a packet queue
 321 ******************************************************************/
 322 static void queue_packet(struct wins_packet_struct *packet)
 323 {
 324         struct wins_packet_struct *p;
 325
 326         if (!packet_queue) {
 327                 packet->prev = NULL;
 328                 packet->next = NULL;
 329                 packet_queue = packet;
 330                 return;
 331         }
 332
 333         /* find the bottom */
 334         for (p=packet_queue;p->next;p=p->next)
 335                 ;
 336
 337         p->next = packet;
 338         packet->next = NULL;
 339         packet->prev = p;
 340 }
 341
 342 /****************************************************************************
 343   Listens for NMB or DGRAM packets, and queues them.
 344   return True if the socket is dead
 345 ***************************************************************************/
 346 static BOOL listen_for_wins_packets(void)
 347 {
 348         int num_interfaces = iface_count();
 349         fd_set fds;
 350         int i, num, s, new_s;
 351         static int maxfd = 0;
 352         struct timeval timeout;
 353
 354         if(listen_set == NULL) {
 355                 if(!create_listen_fdset( &maxfd)) {
 356                         DEBUG(0,("listen_for_packets: Fatal error. unable to create listen set. Exiting.\n"));
 357                         return True;
 358                 }
 359         }
 360
 361         memcpy((char *)&fds, (char *)listen_set, sizeof(fd_set));
 362
 363         timeout.tv_sec = NMBD_SELECT_LOOP;
 364         timeout.tv_usec = 0;
 365
 366         /* Prepare for the select - allow certain signals. */
 367
 368         BlockSignals(False, SIGTERM);
 369
 370         num = sys_select(maxfd+1, &fds, NULL, NULL, &timeout);
 371
 372         /* We can only take signals when we are in the select - block them again here. */
 373
 374         BlockSignals(True, SIGTERM);
 375
 376         if(num == -1)
 377                 return False;
 378
 379         for (; num > 0; num--) {
 380                 s = -1;
 381                 /* check the sockets we are only listening on, waiting to accept */
 382                 for (i=0; i<num_interfaces; i++) {
 383                         struct sockaddr addr;
 384                         socklen_t in_addrlen = sizeof(addr);
 385
 386                         if(FD_ISSET(sock_array[i], &fds)) {
 387                                 s = sock_array[i];
 388                                 /* Clear this so we don't look at it again. */
 389                                 FD_CLR(sock_array[i], &fds);
 390
 391                                 /* accept and add the new socket to the listen set */
 392                                 new_s=accept(s, &addr, &in_addrlen);
 393
 394                                 if (new_s < 0)
 395                                         continue;
 396
 397                                 DEBUG(5,("listen_for_wins_packets: new connection, old: %d, new : %d\n", s, new_s));
 398
 399                                 set_socket_options(new_s, "SO_KEEPALIVE");
 400                                 set_socket_options(new_s, user_socket_options);
 401                                 FD_SET(new_s, listen_set);
 402                                 add_fd_to_sock_array(new_s);
 403                                 maxfd = MAX( maxfd, new_s);
 404                         }
 405                 }
 406
 407                 /*
 408                  * check for the sockets we are waiting data from
 409                  * either client sending datas
 410                  * or reply to our requests
 411                  */
 412                 for (i=num_interfaces; i<listen_number; i++) {
 413                         if(FD_ISSET(sock_array[i], &fds)) {
 414                                 struct wins_packet_struct *packet = read_wins_packet(sock_array[i], timeout.tv_sec);
 415                                 if (packet) {
 416                                         packet->fd = sock_array[i];
 417                                         queue_packet(packet);
 418                                 }
 419                                 DEBUG(2,("listen_for_wins_packets: some data on fd %d\n", sock_array[i]));
 420                                 FD_CLR(sock_array[i], &fds);
 421                                 break;
 422                         }
 423
 424                 }
 425
 426         }
 427
 428         return False;
 429 }
 430
 431
 432 /*******************************************************************
 433   Run elements off the packet queue till its empty
 434 ******************************************************************/
 435
 436 static void run_wins_packet_queue(void)
 437 {
 438         struct wins_packet_struct *p;
 439
 440         while ((p = packet_queue)) {
 441                 packet_queue = p->next;
 442                 if (packet_queue)
 443                         packet_queue->prev = NULL;
 444                 p->next = p->prev = NULL;
 445
 446                 construct_reply(p);
 447
 448                 /* if it was a stop assoc, close the connection */
 449                 if (p->stop_packet) {
 450                         FD_CLR(p->fd, listen_set);
 451                         remove_fd_from_sock_array(p->fd);
 452                         close(p->fd);
 453                 }
 454         }
 455 }
 456
 457 /**************************************************************************** **
 458  The main select loop.
 459  **************************************************************************** */
 460 static void process(void)
 461 {
 462
 463         while( True ) {
 464                 time_t t = time(NULL);
 465
 466                 /* check for internal messages */
 467                 message_dispatch();
 468
 469                 if(listen_for_wins_packets())
 470                         return;
 471
 472                 run_wins_packet_queue();
 473
 474                 run_pull_replication(t);
 475
 476                 run_push_replication(t);
 477
 478                 /*
 479                  * Reload the services file if we got a sighup.
 480                  */
 481
 482                 if(reload_after_sighup) {
 483                         reload_services( True );
 484                         reopen_logs();
 485                         reload_after_sighup = False;
 486                 }
 487
 488                 /* free temp memory */
 489                 talloc_free_children(mem_ctx);
 490
 491                 /* free up temp memory */
 492                 lp_talloc_free();
 493         }
 494 } /* process */
 495
 496 /****************************************************************************
 497   main program
 498 ****************************************************************************/
 499  int main(int argc,char *argv[])
 500 {
 501         /* shall I run as a daemon */
 502         static BOOL is_daemon = False;
 503         static BOOL interactive = False;
 504         static BOOL Fork = True;
 505         static BOOL log_stdout = False;
 506         struct poptOption long_options[] = {
 507                 POPT_AUTOHELP
 508                 { "daemon", 'D', POPT_ARG_VAL, &is_daemon, True, "Become a daemon (default)" },
 509                 { "foreground", 'F', POPT_ARG_VAL, &Fork, False, "Run daemon in foreground (for daemontools, etc)" },
 510                 { "stdout", 'S', POPT_ARG_VAL, &log_stdout, True, "Log to stdout" },
 511                 { "interactive", 'i', POPT_ARG_NONE, NULL, 'i', "Run interactive (not a daemon)" },
 512                 { "port", 'p', POPT_ARG_INT, &wins_port, 'p', "Listen on the specified port" },
 513                 POPT_COMMON_SAMBA
 514                 POPT_TABLEEND
 515         };
 516         int opt;
 517         poptContext pc;
 518
 519 #ifdef HAVE_SET_AUTH_PARAMETERS
 520         set_auth_parameters(argc,argv);
 521 #endif
 522
 523         pc = poptGetContext("wrepld", argc, (const char **)argv, long_options,
 524                                                 POPT_CONTEXT_KEEP_FIRST);
 525
 526         while ((opt = poptGetNextOpt(pc)) != -1) {
 527                 switch (opt)  {
 528                 case 'i':
 529                         interactive = True;
 530                         Fork = False;
 531                         log_stdout = True;
 532                         break;
 533                 }
 534         }
 535
 536
 537         if (log_stdout && Fork) {
 538                 d_printf("Can't log to stdout (-S) unless daemon is in foreground (-F) or interactive (-i)\n");
 539                 poptPrintUsage(pc, stderr, 0);
 540                 exit(1);
 541         }
 542
 543 #ifdef HAVE_SETLUID
 544         /* needed for SecureWare on SCO */
 545         setluid(0);
 546 #endif
 547
 548         sec_init();
 549
 550         load_case_tables();
 551
 552         set_remote_machine_name("wrepld", False);
 553
 554         setup_logging(argv[0],log_stdout);
 555
 556         /* we want to re-seed early to prevent time delays causing
 557            client problems at a later date. (tridge) */
 558         generate_random_buffer(NULL, 0);
 559
 560         /* make absolutely sure we run as root - to handle cases where people
 561            are crazy enough to have it setuid */
 562
 563         gain_root_privilege();
 564         gain_root_group_privilege();
 565
 566         fault_setup((void (*)(void *))exit_server);
 567         CatchSignal(SIGTERM , SIGNAL_CAST dflt_sig);
 568
 569         /* we are never interested in SIGPIPE */
 570         BlockSignals(True,SIGPIPE);
 571
 572 #if defined(SIGFPE)
 573         /* we are never interested in SIGFPE */
 574         BlockSignals(True,SIGFPE);
 575 #endif
 576
 577 #if defined(SIGUSR2)
 578         /* We are no longer interested in USR2 */
 579         BlockSignals(True,SIGUSR2);
 580 #endif
 581
 582         /* POSIX demands that signals are inherited. If the invoking process has
 583          * these signals masked, we will have problems, as we won't recieve them. */
 584         BlockSignals(False, SIGHUP);
 585         BlockSignals(False, SIGUSR1);
 586
 587         /* we want total control over the permissions on created files,
 588            so set our umask to 0 */
 589         umask(0);
 590
 591         reopen_logs();
 592
 593         DEBUG(0,( "wrepld version %s started.\n", SAMBA_VERSION_STRING));
 594         DEBUGADD( 0, ( "%s\n", COPYRIGHT_STARTUP_MESSAGE ) );
 595
 596         DEBUG(2,("uid=%d gid=%d euid=%d egid=%d\n",
 597                  (int)getuid(),(int)getgid(),(int)geteuid(),(int)getegid()));
 598
 599         if (sizeof(uint16) < 2 || sizeof(uint32) < 4) {
 600                 DEBUG(0,("ERROR: Samba is not configured correctly for the word size on your machine\n"));
 601                 exit(1);
 602         }
 603
 604         /*
 605          * Do this before reload_services.
 606          */
 607
 608         if (!reload_services(False))
 609                 return(-1);
 610
 611         if (!init_names())
 612                 return -1;
 613
 614 #ifdef WITH_PROFILE
 615         if (!profile_setup(False)) {
 616                 DEBUG(0,("ERROR: failed to setup profiling\n"));
 617                 return -1;
 618         }
 619 #endif
 620
 621         CatchSignal(SIGHUP,SIGNAL_CAST sig_hup);
 622
 623         DEBUG(3,( "loaded services\n"));
 624
 625         if (!is_daemon && !is_a_socket(0)) {
 626                 DEBUG(0,("standard input is not a socket, assuming -D option\n"));
 627                 is_daemon = True;
 628         }
 629
 630         if (is_daemon && !interactive) {
 631                 DEBUG( 3, ( "Becoming a daemon.\n" ) );
 632                 become_daemon(Fork);
 633         }
 634
 635 #if HAVE_SETPGID
 636         /*
 637          * If we're interactive we want to set our own process group for
 638          * signal management.
 639          */
 640         if (interactive)
 641                 setpgid( (pid_t)0, (pid_t)0);
 642 #endif
 643
 644         if (!directory_exist(lp_lockdir(), NULL)) {
 645                 mkdir(lp_lockdir(), 0755);
 646         }
 647
 648         if (is_daemon) {
 649                 pidfile_create("wrepld");
 650         }
 651
 652         if (!message_init()) {
 653                 exit(1);
 654         }
 655
 656         /* Initialise the memory context */
 657         mem_ctx=talloc_init("wins repl talloc ctx");
 658
 659         /* initialise the global partners table */
 660         partner_count=init_wins_partner_table();
 661
 662         /* We can only take signals in the select. */
 663         BlockSignals( True, SIGTERM );
 664
 665         process();
 666
 667         poptFreeContext(pc);
 668         exit_server("normal exit");
 669         return(0);
 670 }