source/nmbd/nmbd_browsesync.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    NBT netbios routines and daemon - version 2
   4    Copyright (C) Andrew Tridgell 1994-1998
   5    Copyright (C) Luke Kenneth Casson Leighton 1994-1998
   6    Copyright (C) Jeremy Allison 1994-2003
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 2 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program; if not, write to the Free Software
  20    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  21
  22 */
  23
  24 #include "includes.h"
  25
  26 /* This is our local master browser list database. */
  27 extern ubi_dlList lmb_browserlist[];
  28
  29 /****************************************************************************
  30 As a domain master browser, do a sync with a local master browser.
  31 **************************************************************************/
  32
  33 static void sync_with_lmb(struct browse_cache_record *browc)
  34 {
  35         struct work_record *work;
  36
  37         if( !(work = find_workgroup_on_subnet(unicast_subnet, browc->work_group)) ) {
  38                 if( DEBUGLVL( 0 ) ) {
  39                         dbgtext( "sync_with_lmb:\n" );
  40                         dbgtext( "Failed to get a workgroup for a local master browser " );
  41                         dbgtext( "cache entry workgroup " );
  42                         dbgtext( "%s, server %s\n", browc->work_group, browc->lmb_name );
  43                 }
  44                 return;
  45         }
  46
  47         /* We should only be doing this if we are a domain master browser for
  48                 the given workgroup. Ensure this is so. */
  49
  50         if(!AM_DOMAIN_MASTER_BROWSER(work)) {
  51                 if( DEBUGLVL( 0 ) ) {
  52                         dbgtext( "sync_with_lmb:\n" );
  53                         dbgtext( "We are trying to sync with a local master browser " );
  54                         dbgtext( "%s for workgroup %s\n", browc->lmb_name, browc->work_group );
  55                         dbgtext( "and we are not a domain master browser on this workgroup.\n" );
  56                         dbgtext( "Error!\n" );
  57                 }
  58                 return;
  59         }
  60
  61         if( DEBUGLVL( 2 ) ) {
  62                 dbgtext( "sync_with_lmb:\n" );
  63                 dbgtext( "Initiating sync with local master browser " );
  64                 dbgtext( "%s<0x20> at IP %s ", browc->lmb_name, inet_ntoa(browc->ip) );
  65                 dbgtext( "for workgroup %s\n", browc->work_group );
  66         }
  67
  68         sync_browse_lists(work, browc->lmb_name, 0x20, browc->ip, True, True);
  69
  70         browc->sync_time += (CHECK_TIME_DMB_TO_LMB_SYNC * 60);
  71 }
  72
  73 /****************************************************************************
  74 Sync or expire any local master browsers.
  75 **************************************************************************/
  76
  77 void dmb_expire_and_sync_browser_lists(time_t t)
  78 {
  79         static time_t last_run = 0;
  80         struct browse_cache_record *browc;
  81
  82         /* Only do this every 20 seconds. */
  83         if (t - last_run < 20)
  84                 return;
  85
  86         last_run = t;
  87
  88         expire_lmb_browsers(t);
  89
  90         for( browc = (struct browse_cache_record *)ubi_dlFirst( lmb_browserlist );
  91                         browc;
  92                         browc = (struct browse_cache_record *)ubi_dlNext( browc ) ) {
  93                 if (browc->sync_time < t)
  94                         sync_with_lmb(browc);
  95         }
  96 }
  97
  98 /****************************************************************************
  99 As a local master browser, send an announce packet to the domain master browser.
 100 **************************************************************************/
 101
 102 static void announce_local_master_browser_to_domain_master_browser( struct work_record *work)
 103 {
 104         pstring outbuf;
 105         unstring myname;
 106         unstring dmb_name;
 107         char *p;
 108
 109         if(ismyip(work->dmb_addr)) {
 110                 if( DEBUGLVL( 2 ) ) {
 111                         dbgtext( "announce_local_master_browser_to_domain_master_browser:\n" );
 112                         dbgtext( "We are both a domain and a local master browser for " );
 113                         dbgtext( "workgroup %s.  ", work->work_group );
 114                         dbgtext( "Do not announce to ourselves.\n" );
 115                 }
 116                 return;
 117         }
 118
 119         memset(outbuf,'\0',sizeof(outbuf));
 120         p = outbuf;
 121         SCVAL(p,0,ANN_MasterAnnouncement);
 122         p++;
 123
 124         unstrcpy(myname, global_myname());
 125         strupper_m(myname);
 126         myname[15]='\0';
 127         /* The call below does CH_UNIX -> CH_DOS conversion. JRA */
 128         push_pstring_base(p, myname, outbuf);
 129
 130         p = skip_string(p,1);
 131
 132         if( DEBUGLVL( 4 ) ) {
 133                 dbgtext( "announce_local_master_browser_to_domain_master_browser:\n" );
 134                 dbgtext( "Sending local master announce to " );
 135                 dbgtext( "%s for workgroup %s.\n", nmb_namestr(&work->dmb_name),
 136                                         work->work_group );
 137         }
 138
 139         /* Target name for send_mailslot must be in UNIX charset. */
 140         pull_ascii_nstring(dmb_name, sizeof(dmb_name), work->dmb_name.name);
 141         send_mailslot(True, BROWSE_MAILSLOT, outbuf,PTR_DIFF(p,outbuf),
 142                 global_myname(), 0x0, dmb_name, 0x0,
 143                 work->dmb_addr, FIRST_SUBNET->myip, DGRAM_PORT);
 144 }
 145
 146 /****************************************************************************
 147 As a local master browser, do a sync with a domain master browser.
 148 **************************************************************************/
 149
 150 static void sync_with_dmb(struct work_record *work)
 151 {
 152         unstring dmb_name;
 153
 154         if( DEBUGLVL( 2 ) ) {
 155                 dbgtext( "sync_with_dmb:\n" );
 156                 dbgtext( "Initiating sync with domain master browser " );
 157                 dbgtext( "%s ", nmb_namestr(&work->dmb_name) );
 158                 dbgtext( "at IP %s ", inet_ntoa(work->dmb_addr) );
 159                 dbgtext( "for workgroup %s\n", work->work_group );
 160         }
 161
 162         pull_ascii_nstring(dmb_name, sizeof(dmb_name), work->dmb_name.name);
 163         sync_browse_lists(work, dmb_name, work->dmb_name.name_type,
 164                 work->dmb_addr, False, True);
 165 }
 166
 167 /****************************************************************************
 168   Function called when a node status query to a domain master browser IP succeeds.
 169 ****************************************************************************/
 170
 171 static void domain_master_node_status_success(struct subnet_record *subrec,
 172                                               struct userdata_struct *userdata,
 173                                               struct res_rec *answers,
 174                                               struct in_addr from_ip)
 175 {
 176         struct work_record *work = find_workgroup_on_subnet( subrec, userdata->data);
 177
 178         if( work == NULL ) {
 179                 if( DEBUGLVL( 0 ) ) {
 180                         dbgtext( "domain_master_node_status_success:\n" );
 181                         dbgtext( "Unable to find workgroup " );
 182                         dbgtext( "%s on subnet %s.\n", userdata->data, subrec->subnet_name );
 183                 }
 184                 return;
 185         }
 186
 187         if( DEBUGLVL( 3 ) ) {
 188                 dbgtext( "domain_master_node_status_success:\n" );
 189                 dbgtext( "Success in node status for workgroup " );
 190                 dbgtext( "%s from ip %s\n", work->work_group, inet_ntoa(from_ip) );
 191         }
 192
 193   /* Go through the list of names found at answers->rdata and look for
 194      the first SERVER<0x20> name. */
 195
 196         if(answers->rdata != NULL) {
 197                 char *p = answers->rdata;
 198                 int numnames = CVAL(p, 0);
 199
 200                 p += 1;
 201
 202                 while (numnames--) {
 203                         unstring qname;
 204                         uint16 nb_flags;
 205                         int name_type;
 206
 207                         pull_ascii_nstring(qname, sizeof(qname), p);
 208                         name_type = CVAL(p,15);
 209                         nb_flags = get_nb_flags(&p[16]);
 210                         trim_char(qname,'\0',' ');
 211
 212                         p += 18;
 213
 214                         if(!(nb_flags & NB_GROUP) && (name_type == 0x20)) {
 215                                 struct nmb_name nmbname;
 216
 217                                 make_nmb_name(&nmbname, qname, name_type);
 218
 219                                 /* Copy the dmb name and IP address
 220                                         into the workgroup struct. */
 221
 222                                 work->dmb_name = nmbname;
 223                                 putip((char *)&work->dmb_addr, &from_ip);
 224
 225                                 /* Do the local master browser announcement to the domain
 226                                         master browser name and IP. */
 227                                 announce_local_master_browser_to_domain_master_browser( work );
 228
 229                                 /* Now synchronise lists with the domain master browser. */
 230                                 sync_with_dmb(work);
 231                                 break;
 232                         }
 233                 }
 234         } else if( DEBUGLVL( 0 ) ) {
 235                 dbgtext( "domain_master_node_status_success:\n" );
 236                 dbgtext( "Failed to find a SERVER<0x20> name in reply from IP " );
 237                 dbgtext( "%s.\n", inet_ntoa(from_ip) );
 238         }
 239 }
 240
 241 /****************************************************************************
 242   Function called when a node status query to a domain master browser IP fails.
 243 ****************************************************************************/
 244
 245 static void domain_master_node_status_fail(struct subnet_record *subrec,
 246                        struct response_record *rrec)
 247 {
 248         struct userdata_struct *userdata = rrec->userdata;
 249
 250         if( DEBUGLVL( 0 ) ) {
 251                 dbgtext( "domain_master_node_status_fail:\n" );
 252                 dbgtext( "Doing a node status request to the domain master browser\n" );
 253                 dbgtext( "for workgroup %s ", userdata ? userdata->data : "NULL" );
 254                 dbgtext( "at IP %s failed.\n", inet_ntoa(rrec->packet->ip) );
 255                 dbgtext( "Cannot sync browser lists.\n" );
 256         }
 257 }
 258
 259 /****************************************************************************
 260   Function called when a query for a WORKGROUP<1b> name succeeds.
 261 ****************************************************************************/
 262
 263 static void find_domain_master_name_query_success(struct subnet_record *subrec,
 264                         struct userdata_struct *userdata_in,
 265                         struct nmb_name *q_name, struct in_addr answer_ip, struct res_rec *rrec)
 266 {
 267         /*
 268          * Unfortunately, finding the IP address of the Domain Master Browser,
 269          * as we have here, is not enough. We need to now do a sync to the
 270          * SERVERNAME<0x20> NetBIOS name, as only recent NT servers will
 271          * respond to the SMBSERVER name. To get this name from IP
 272          * address we do a Node status request, and look for the first
 273          * NAME<0x20> in the response, and take that as the server name.
 274          * We also keep a cache of the Domain Master Browser name for this
 275          * workgroup in the Workgroup struct, so that if the same IP addess
 276          * is returned every time, we don't need to do the node status
 277          * request.
 278          */
 279
 280         struct work_record *work;
 281         struct nmb_name nmbname;
 282         struct userdata_struct *userdata;
 283         size_t size = sizeof(struct userdata_struct) + sizeof(fstring)+1;
 284         unstring qname;
 285
 286         pull_ascii_nstring(qname, sizeof(qname), q_name->name);
 287         if( !(work = find_workgroup_on_subnet(subrec, qname)) ) {
 288                 if( DEBUGLVL( 0 ) ) {
 289                         dbgtext( "find_domain_master_name_query_success:\n" );
 290                         dbgtext( "Failed to find workgroup %s\n", qname);
 291                 }
 292         return;
 293   }
 294
 295   /* First check if we already have a dmb for this workgroup. */
 296
 297         if(!is_zero_ip(work->dmb_addr) && ip_equal(work->dmb_addr, answer_ip)) {
 298                 /* Do the local master browser announcement to the domain
 299                         master browser name and IP. */
 300                 announce_local_master_browser_to_domain_master_browser( work );
 301
 302                 /* Now synchronise lists with the domain master browser. */
 303                 sync_with_dmb(work);
 304                 return;
 305         } else {
 306                 zero_ip(&work->dmb_addr);
 307         }
 308
 309         /* Now initiate the node status request. */
 310
 311         /* We used to use the name "*",0x0 here, but some Windows
 312          * servers don't answer that name. However we *know* they
 313          * have the name workgroup#1b (as we just looked it up).
 314          * So do the node status request on this name instead.
 315          * Found at LBL labs. JRA.
 316          */
 317
 318         make_nmb_name(&nmbname,work->work_group,0x1b);
 319
 320         /* Put the workgroup name into the userdata so we know
 321          what workgroup we're talking to when the reply comes
 322          back. */
 323
 324         /* Setup the userdata_struct - this is copied so we can use
 325         a stack variable for this. */
 326
 327         if((userdata = (struct userdata_struct *)malloc(size)) == NULL) {
 328                 DEBUG(0, ("find_domain_master_name_query_success: malloc fail.\n"));
 329                 return;
 330         }
 331
 332         userdata->copy_fn = NULL;
 333         userdata->free_fn = NULL;
 334         userdata->userdata_len = strlen(work->work_group)+1;
 335         overmalloc_safe_strcpy(userdata->data, work->work_group, size - sizeof(*userdata) - 1);
 336
 337         node_status( subrec, &nmbname, answer_ip,
 338                 domain_master_node_status_success,
 339                 domain_master_node_status_fail,
 340                 userdata);
 341
 342         zero_free(userdata, size);
 343 }
 344
 345 /****************************************************************************
 346   Function called when a query for a WORKGROUP<1b> name fails.
 347   ****************************************************************************/
 348
 349 static void find_domain_master_name_query_fail(struct subnet_record *subrec,
 350                                     struct response_record *rrec,
 351                                     struct nmb_name *question_name, int fail_code)
 352 {
 353         if( DEBUGLVL( 0 ) ) {
 354                 dbgtext( "find_domain_master_name_query_fail:\n" );
 355                 dbgtext( "Unable to find the Domain Master Browser name " );
 356                 dbgtext( "%s for the workgroup %s.\n",
 357                         nmb_namestr(question_name), question_name->name );
 358                 dbgtext( "Unable to sync browse lists in this workgroup.\n" );
 359         }
 360 }
 361
 362 /****************************************************************************
 363 As a local master browser for a workgroup find the domain master browser
 364 name, announce ourselves as local master browser to it and then pull the
 365 full domain browse lists from it onto the given subnet.
 366 **************************************************************************/
 367
 368 void announce_and_sync_with_domain_master_browser( struct subnet_record *subrec,
 369                                                    struct work_record *work)
 370 {
 371         /* Only do this if we are using a WINS server. */
 372         if(we_are_a_wins_client() == False) {
 373                 if( DEBUGLVL( 10 ) ) {
 374                         dbgtext( "announce_and_sync_with_domain_master_browser:\n" );
 375                         dbgtext( "Ignoring, as we are not a WINS client.\n" );
 376                 }
 377                 return;
 378         }
 379
 380         /* First, query for the WORKGROUP<1b> name from the WINS server. */
 381         query_name(unicast_subnet, work->work_group, 0x1b,
 382              find_domain_master_name_query_success,
 383              find_domain_master_name_query_fail,
 384              NULL);
 385 }
 386
 387 /****************************************************************************
 388   Function called when a node status query to a domain master browser IP succeeds.
 389   This function is only called on query to a Samba 1.9.18 or above WINS server.
 390
 391   Note that adding the workgroup name is enough for this workgroup to be
 392   browsable by clients, as clients query the WINS server or broadcast
 393   nets for the WORKGROUP<1b> name when they want to browse a workgroup
 394   they are not in. We do not need to do a sync with this Domain Master
 395   Browser in order for our browse clients to see machines in this workgroup.
 396   JRA.
 397 ****************************************************************************/
 398
 399 static void get_domain_master_name_node_status_success(struct subnet_record *subrec,
 400                                               struct userdata_struct *userdata,
 401                                               struct res_rec *answers,
 402                                               struct in_addr from_ip)
 403 {
 404         struct work_record *work;
 405         unstring server_name;
 406
 407         server_name[0] = 0;
 408
 409         if( DEBUGLVL( 3 ) ) {
 410                 dbgtext( "get_domain_master_name_node_status_success:\n" );
 411                 dbgtext( "Success in node status from ip %s\n", inet_ntoa(from_ip) );
 412         }
 413
 414         /*
 415          * Go through the list of names found at answers->rdata and look for
 416          * the first WORKGROUP<0x1b> name.
 417          */
 418
 419         if(answers->rdata != NULL) {
 420                 char *p = answers->rdata;
 421                 int numnames = CVAL(p, 0);
 422
 423                 p += 1;
 424
 425                 while (numnames--) {
 426                         unstring qname;
 427                         uint16 nb_flags;
 428                         int name_type;
 429
 430                         pull_ascii_nstring(qname, sizeof(qname), p);
 431                         name_type = CVAL(p,15);
 432                         nb_flags = get_nb_flags(&p[16]);
 433                         trim_char(qname,'\0',' ');
 434
 435                         p += 18;
 436
 437                         if(!(nb_flags & NB_GROUP) && (name_type == 0x00) &&
 438                                         server_name[0] == 0) {
 439                                 /* this is almost certainly the server netbios name */
 440                                 unstrcpy(server_name, qname);
 441                                 continue;
 442                         }
 443
 444                         if(!(nb_flags & NB_GROUP) && (name_type == 0x1b)) {
 445                                 if( DEBUGLVL( 5 ) ) {
 446                                         dbgtext( "get_domain_master_name_node_status_success:\n" );
 447                                         dbgtext( "%s(%s) ", server_name, inet_ntoa(from_ip) );
 448                                         dbgtext( "is a domain master browser for workgroup " );
 449                                         dbgtext( "%s. Adding this name.\n", qname );
 450                                 }
 451
 452                                 /*
 453                                  * If we don't already know about this workgroup, add it
 454                                  * to the workgroup list on the unicast_subnet.
 455                                  */
 456
 457                                 if((work = find_workgroup_on_subnet( subrec, qname)) == NULL) {
 458                                         struct nmb_name nmbname;
 459                                         /*
 460                                          * Add it - with an hour in the cache.
 461                                          */
 462                                         if(!(work= create_workgroup_on_subnet(subrec, qname, 60*60)))
 463                                                 return;
 464
 465                                         /* remember who the master is */
 466                                         unstrcpy(work->local_master_browser_name, server_name);
 467                                         make_nmb_name(&nmbname, server_name, 0x20);
 468                                         work->dmb_name = nmbname;
 469                                         work->dmb_addr = from_ip;
 470                                 }
 471                                 break;
 472                         }
 473                 }
 474         } else if( DEBUGLVL( 0 ) ) {
 475                 dbgtext( "get_domain_master_name_node_status_success:\n" );
 476                 dbgtext( "Failed to find a WORKGROUP<0x1b> name in reply from IP " );
 477                 dbgtext( "%s.\n", inet_ntoa(from_ip) );
 478         }
 479 }
 480
 481 /****************************************************************************
 482   Function called when a node status query to a domain master browser IP fails.
 483 ****************************************************************************/
 484
 485 static void get_domain_master_name_node_status_fail(struct subnet_record *subrec,
 486                        struct response_record *rrec)
 487 {
 488         if( DEBUGLVL( 0 ) ) {
 489                 dbgtext( "get_domain_master_name_node_status_fail:\n" );
 490                 dbgtext( "Doing a node status request to the domain master browser " );
 491                 dbgtext( "at IP %s failed.\n", inet_ntoa(rrec->packet->ip) );
 492                 dbgtext( "Cannot get workgroup name.\n" );
 493         }
 494 }
 495
 496 /****************************************************************************
 497   Function called when a query for *<1b> name succeeds.
 498 ****************************************************************************/
 499
 500 static void find_all_domain_master_names_query_success(struct subnet_record *subrec,
 501                         struct userdata_struct *userdata_in,
 502                         struct nmb_name *q_name, struct in_addr answer_ip, struct res_rec *rrec)
 503 {
 504         /*
 505          * We now have a list of all the domain master browsers for all workgroups
 506          * that have registered with the WINS server. Now do a node status request
 507          * to each one and look for the first 1b name in the reply. This will be
 508          * the workgroup name that we will add to the unicast subnet as a 'non-local'
 509          * workgroup.
 510          */
 511
 512         struct nmb_name nmbname;
 513         struct in_addr send_ip;
 514         int i;
 515
 516         if( DEBUGLVL( 5 ) ) {
 517                 dbgtext( "find_all_domain_master_names_query_succes:\n" );
 518                 dbgtext( "Got answer from WINS server of %d ", (rrec->rdlength / 6) );
 519                 dbgtext( "IP addresses for Domain Master Browsers.\n" );
 520         }
 521
 522         for(i = 0; i < rrec->rdlength / 6; i++) {
 523                 /* Initiate the node status requests. */
 524                 make_nmb_name(&nmbname, "*", 0);
 525
 526                 putip((char *)&send_ip, (char *)&rrec->rdata[(i*6) + 2]);
 527
 528                 /*
 529                  * Don't send node status requests to ourself.
 530                  */
 531
 532                 if(ismyip( send_ip )) {
 533                         if( DEBUGLVL( 5 ) ) {
 534                                 dbgtext( "find_all_domain_master_names_query_succes:\n" );
 535                                 dbgtext( "Not sending node status to our own IP " );
 536                                 dbgtext( "%s.\n", inet_ntoa(send_ip) );
 537                         }
 538                         continue;
 539                 }
 540
 541                 if( DEBUGLVL( 5 ) ) {
 542                         dbgtext( "find_all_domain_master_names_query_success:\n" );
 543                         dbgtext( "Sending node status request to IP %s.\n", inet_ntoa(send_ip) );
 544                 }
 545
 546                 node_status( subrec, &nmbname, send_ip,
 547                                 get_domain_master_name_node_status_success,
 548                                 get_domain_master_name_node_status_fail,
 549                                 NULL);
 550         }
 551 }
 552
 553 /****************************************************************************
 554   Function called when a query for *<1b> name fails.
 555   ****************************************************************************/
 556 static void find_all_domain_master_names_query_fail(struct subnet_record *subrec,
 557                                     struct response_record *rrec,
 558                                     struct nmb_name *question_name, int fail_code)
 559 {
 560         if( DEBUGLVL( 10 ) ) {
 561                 dbgtext( "find_domain_master_name_query_fail:\n" );
 562                 dbgtext( "WINS server did not reply to a query for name " );
 563                 dbgtext( "%s.\nThis means it ", nmb_namestr(question_name) );
 564                 dbgtext( "is probably not a Samba 1.9.18 or above WINS server.\n" );
 565         }
 566 }
 567
 568 /****************************************************************************
 569  If we are a domain master browser on the unicast subnet, do a query to the
 570  WINS server for the *<1b> name. This will only work to a Samba WINS server,
 571  so ignore it if we fail. If we succeed, contact each of the IP addresses in
 572  turn and do a node status request to them. If this succeeds then look for a
 573  <1b> name in the reply - this is the workgroup name. Add this to the unicast
 574  subnet. This is expensive, so we only do this every 15 minutes.
 575 **************************************************************************/
 576
 577 void collect_all_workgroup_names_from_wins_server(time_t t)
 578 {
 579         static time_t lastrun = 0;
 580         struct work_record *work;
 581
 582         /* Only do this if we are using a WINS server. */
 583         if(we_are_a_wins_client() == False)
 584                 return;
 585
 586         /* Check to see if we are a domain master browser on the unicast subnet. */
 587         if((work = find_workgroup_on_subnet( unicast_subnet, lp_workgroup())) == NULL) {
 588                 if( DEBUGLVL( 0 ) ) {
 589                         dbgtext( "collect_all_workgroup_names_from_wins_server:\n" );
 590                         dbgtext( "Cannot find my workgroup %s ", lp_workgroup() );
 591                         dbgtext( "on subnet %s.\n", unicast_subnet->subnet_name );
 592                 }
 593                 return;
 594         }
 595
 596         if(!AM_DOMAIN_MASTER_BROWSER(work))
 597                 return;
 598
 599         if ((lastrun != 0) && (t < lastrun + (15 * 60)))
 600                 return;
 601
 602         lastrun = t;
 603
 604         /* First, query for the *<1b> name from the WINS server. */
 605         query_name(unicast_subnet, "*", 0x1b,
 606                 find_all_domain_master_names_query_success,
 607                 find_all_domain_master_names_query_fail,
 608                 NULL);
 609 }
 610
 611
 612 /****************************************************************************
 613  If we are a domain master browser on the unicast subnet, do a regular sync
 614  with all other DMBs that we know of on that subnet.
 615
 616 To prevent exponential network traffic with large numbers of workgroups
 617 we use a randomised system where sync probability is inversely proportional
 618 to the number of known workgroups
 619 **************************************************************************/
 620
 621 void sync_all_dmbs(time_t t)
 622 {
 623         static time_t lastrun = 0;
 624         struct work_record *work;
 625         int count=0;
 626
 627         /* Only do this if we are using a WINS server. */
 628         if(we_are_a_wins_client() == False)
 629                 return;
 630
 631         /* Check to see if we are a domain master browser on the
 632            unicast subnet. */
 633         work = find_workgroup_on_subnet(unicast_subnet, lp_workgroup());
 634         if (!work)
 635                 return;
 636
 637         if (!AM_DOMAIN_MASTER_BROWSER(work))
 638                 return;
 639
 640         if ((lastrun != 0) && (t < lastrun + (5 * 60)))
 641                 return;
 642
 643         /* count how many syncs we might need to do */
 644         for (work=unicast_subnet->workgrouplist; work; work = work->next) {
 645                 if (strcmp(lp_workgroup(), work->work_group)) {
 646                         count++;
 647                 }
 648         }
 649
 650         /* sync with a probability of 1/count */
 651         for (work=unicast_subnet->workgrouplist; work; work = work->next) {
 652                 if (strcmp(lp_workgroup(), work->work_group)) {
 653                         unstring dmb_name;
 654
 655                         if (((unsigned)sys_random()) % count != 0)
 656                                 continue;
 657
 658                         lastrun = t;
 659
 660                         if (!work->dmb_name.name[0]) {
 661                                 /* we don't know the DMB - assume it is
 662                                    the same as the unicast local master */
 663                                 make_nmb_name(&work->dmb_name,
 664                                               work->local_master_browser_name,
 665                                               0x20);
 666                         }
 667
 668                         pull_ascii_nstring(dmb_name, sizeof(dmb_name), work->dmb_name.name);
 669
 670                         DEBUG(3,("Initiating DMB<->DMB sync with %s(%s)\n",
 671                                  dmb_name, inet_ntoa(work->dmb_addr)));
 672
 673                         sync_browse_lists(work,
 674                                           dmb_name,
 675                                           work->dmb_name.name_type,
 676                                           work->dmb_addr, False, False);
 677                 }
 678         }
 679 }