source3/nmbd/nmbd_incomingdgrams.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 1994-1998
   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 extern BOOL found_lm_clients;
  27
  28 #if 0
  29
  30 /* XXXX note: This function is currently unsuitable for use, as it
  31    does not properly check that a server is in a fit state to become
  32    a backup browser before asking it to be one.
  33    The code is left here to be worked on at a later date.
  34 */
  35
  36 /****************************************************************************
  37 Tell a server to become a backup browser
  38 **************************************************************************/
  39
  40 void tell_become_backup(void)
  41 {
  42   struct subnet_record *subrec;
  43   for (subrec = FIRST_SUBNET; subrec; subrec = NEXT_SUBNET_EXCLUDING_UNICAST(subrec))
  44   {
  45     struct work_record *work;
  46     for (work = subrec->workgrouplist; work; work = work->next)
  47     {
  48       struct server_record *servrec;
  49       int num_servers = 0;
  50       int num_backups = 0;
  51
  52       for (servrec = work->serverlist; servrec; servrec = servrec->next)
  53       {
  54         num_servers++;
  55
  56         if (is_myname(servrec->serv.name))
  57           continue;
  58
  59         if (servrec->serv.type & SV_TYPE_BACKUP_BROWSER)
  60         {
  61           num_backups++;
  62           continue;
  63         }
  64
  65         if (servrec->serv.type & SV_TYPE_MASTER_BROWSER)
  66           continue;
  67
  68         if (!(servrec->serv.type & SV_TYPE_POTENTIAL_BROWSER))
  69           continue;
  70
  71         DEBUG(3,("num servers: %d num backups: %d\n",
  72               num_servers, num_backups));
  73
  74         /* make first server a backup server. thereafter make every
  75            tenth server a backup server */
  76         if (num_backups != 0 && (num_servers+9) / num_backups > 10)
  77           continue;
  78
  79         DEBUG(2,("sending become backup to %s %s for %s\n",
  80              servrec->serv.name, inet_ntoa(subrec->bcast_ip),
  81              work->work_group));
  82
  83         /* type 11 request from MYNAME(20) to WG(1e) for SERVER */
  84         do_announce_request(servrec->serv.name, work->work_group,
  85               ANN_BecomeBackup, 0x20, 0x1e, subrec->bcast_ip);
  86       }
  87     }
  88   }
  89 }
  90 #endif
  91
  92 /*******************************************************************
  93   Process an incoming host announcement packet.
  94 *******************************************************************/
  95
  96 void process_host_announce(struct subnet_record *subrec, struct packet_struct *p, char *buf)
  97 {
  98         struct dgram_packet *dgram = &p->packet.dgram;
  99         int ttl = IVAL(buf,1)/1000;
 100         unstring announce_name;
 101         uint32 servertype = IVAL(buf,23);
 102         fstring comment;
 103         struct work_record *work;
 104         struct server_record *servrec;
 105         unstring work_name;
 106         unstring source_name;
 107
 108         START_PROFILE(host_announce);
 109
 110         pull_ascii_fstring(comment, buf+31);
 111
 112         pull_ascii_nstring(announce_name, sizeof(announce_name), buf+5);
 113         pull_ascii_nstring(source_name, sizeof(source_name), dgram->source_name.name);
 114
 115         DEBUG(3,("process_host_announce: from %s<%02x> IP %s to \
 116 %s for server %s.\n", source_name, source_name[15], inet_ntoa(p->ip),
 117                         nmb_namestr(&dgram->dest_name),announce_name));
 118
 119         DEBUG(5,("process_host_announce: ttl=%d server type=%08x comment=%s\n",
 120                 ttl, servertype,comment));
 121
 122         /* Filter servertype to remove impossible bits. */
 123         servertype &= ~(SV_TYPE_LOCAL_LIST_ONLY|SV_TYPE_DOMAIN_ENUM);
 124
 125         /* A host announcement must be sent to the name WORKGROUP<1d>. */
 126         if(dgram->dest_name.name_type != 0x1d) {
 127                 DEBUG(2,("process_host_announce: incorrect name type for destination from IP %s \
 128 (was %02x) should be 0x1d. Allowing packet anyway.\n",
 129                         inet_ntoa(p->ip), dgram->dest_name.name_type));
 130                 /* Change it so it was. */
 131                 dgram->dest_name.name_type = 0x1d;
 132         }
 133
 134         /* For a host announce the workgroup name is the destination name. */
 135         pull_ascii_nstring(work_name, sizeof(work_name), dgram->dest_name.name);
 136
 137         /*
 138          * Syntax servers version 5.1 send HostAnnounce packets to
 139          * *THE WRONG NAME*. They send to LOCAL_MASTER_BROWSER_NAME<00>
 140          * instead of WORKGROUP<1d> name. So to fix this we check if
 141          * the workgroup name is our own name, and if so change it
 142          * to be our primary workgroup name.
 143          */
 144
 145         if(strequal(work_name, global_myname()))
 146                 unstrcpy(work_name,lp_workgroup());
 147
 148         /*
 149          * We are being very agressive here in adding a workgroup
 150          * name on the basis of a host announcing itself as being
 151          * in that workgroup. Maybe we should wait for the workgroup
 152          * announce instead ? JRA.
 153          */
 154
 155         work = find_workgroup_on_subnet(subrec, work_name);
 156
 157         if(servertype != 0) {
 158                 if (work ==NULL ) {
 159                         /* We have no record of this workgroup. Add it. */
 160                         if((work = create_workgroup_on_subnet(subrec, work_name, ttl))==NULL)
 161                                 goto done;
 162                 }
 163
 164                 if((servrec = find_server_in_workgroup( work, announce_name))==NULL) {
 165                         /* If this server is not already in the workgroup, add it. */
 166                         create_server_on_workgroup(work, announce_name,
 167                                 servertype|SV_TYPE_LOCAL_LIST_ONLY,
 168                                 ttl, comment);
 169                 } else {
 170                         /* Update the record. */
 171                         servrec->serv.type = servertype|SV_TYPE_LOCAL_LIST_ONLY;
 172                         update_server_ttl( servrec, ttl);
 173                         fstrcpy(servrec->serv.comment,comment);
 174                 }
 175         } else {
 176                 /*
 177                  * This server is announcing it is going down. Remove it from the
 178                  * workgroup.
 179                  */
 180                 if(!is_myname(announce_name) && (work != NULL) &&
 181                                 ((servrec = find_server_in_workgroup( work, announce_name))!=NULL)) {
 182                         remove_server_from_workgroup( work, servrec);
 183                 }
 184         }
 185
 186         subrec->work_changed = True;
 187 done:
 188
 189         END_PROFILE(host_announce);
 190 }
 191
 192 /*******************************************************************
 193   Process an incoming WORKGROUP announcement packet.
 194 *******************************************************************/
 195
 196 void process_workgroup_announce(struct subnet_record *subrec, struct packet_struct *p, char *buf)
 197 {
 198         struct dgram_packet *dgram = &p->packet.dgram;
 199         int ttl = IVAL(buf,1)/1000;
 200         unstring workgroup_announce_name;
 201         unstring master_name;
 202         uint32 servertype = IVAL(buf,23);
 203         struct work_record *work;
 204         unstring source_name;
 205         unstring dest_name;
 206
 207         START_PROFILE(workgroup_announce);
 208
 209         pull_ascii_nstring(workgroup_announce_name,sizeof(workgroup_announce_name),buf+5);
 210         pull_ascii_nstring(master_name,sizeof(master_name),buf+31);
 211         pull_ascii_nstring(source_name,sizeof(source_name),dgram->source_name.name);
 212         pull_ascii_nstring(dest_name,sizeof(dest_name),dgram->dest_name.name);
 213
 214         DEBUG(3,("process_workgroup_announce: from %s<%02x> IP %s to \
 215 %s for workgroup %s.\n", source_name, source_name[15], inet_ntoa(p->ip),
 216                         nmb_namestr(&dgram->dest_name),workgroup_announce_name));
 217
 218         DEBUG(5,("process_workgroup_announce: ttl=%d server type=%08x master browser=%s\n",
 219                 ttl, servertype, master_name));
 220
 221         /* Workgroup announcements must only go to the MSBROWSE name. */
 222         if (!strequal(dest_name, MSBROWSE) || (dgram->dest_name.name_type != 0x1)) {
 223                 DEBUG(0,("process_workgroup_announce: from IP %s should be to __MSBROWSE__<0x01> not %s\n",
 224                         inet_ntoa(p->ip), nmb_namestr(&dgram->dest_name)));
 225                 goto done;
 226         }
 227
 228         if ((work = find_workgroup_on_subnet(subrec, workgroup_announce_name))==NULL) {
 229                 /* We have no record of this workgroup. Add it. */
 230                 if((work = create_workgroup_on_subnet(subrec, workgroup_announce_name, ttl))==NULL)
 231                         goto done;
 232         } else {
 233                 /* Update the workgroup death_time. */
 234                 update_workgroup_ttl(work, ttl);
 235         }
 236
 237         if(*work->local_master_browser_name == '\0') {
 238                 /* Set the master browser name. */
 239                 set_workgroup_local_master_browser_name( work, master_name );
 240         }
 241
 242         subrec->work_changed = True;
 243
 244 done:
 245
 246         END_PROFILE(workgroup_announce);
 247 }
 248
 249 /*******************************************************************
 250   Process an incoming local master browser announcement packet.
 251 *******************************************************************/
 252
 253 void process_local_master_announce(struct subnet_record *subrec, struct packet_struct *p, char *buf)
 254 {
 255         struct dgram_packet *dgram = &p->packet.dgram;
 256         int ttl = IVAL(buf,1)/1000;
 257         unstring server_name;
 258         uint32 servertype = IVAL(buf,23);
 259         fstring comment;
 260         unstring work_name;
 261         struct work_record *work;
 262         struct server_record *servrec;
 263         unstring source_name;
 264
 265         START_PROFILE(local_master_announce);
 266
 267         pull_ascii_nstring(server_name,sizeof(server_name),buf+5);
 268         pull_ascii_fstring(comment, buf+31);
 269         pull_ascii_nstring(source_name, sizeof(source_name), dgram->source_name.name);
 270         pull_ascii_nstring(work_name, sizeof(work_name), dgram->dest_name.name);
 271
 272         DEBUG(3,("process_local_master_announce: from %s<%02x> IP %s to \
 273 %s for server %s.\n", source_name, source_name[15], inet_ntoa(p->ip),
 274                 nmb_namestr(&dgram->dest_name),server_name));
 275
 276         DEBUG(5,("process_local_master_announce: ttl=%d server type=%08x comment=%s\n",
 277                 ttl, servertype, comment));
 278
 279         /* A local master announcement must be sent to the name WORKGROUP<1e>. */
 280         if(dgram->dest_name.name_type != 0x1e) {
 281                 DEBUG(0,("process_local_master_announce: incorrect name type for destination from IP %s \
 282 (was %02x) should be 0x1e. Ignoring packet.\n",
 283                         inet_ntoa(p->ip), dgram->dest_name.name_type));
 284                 goto done;
 285         }
 286
 287         /* Filter servertype to remove impossible bits. */
 288         servertype &= ~(SV_TYPE_LOCAL_LIST_ONLY|SV_TYPE_DOMAIN_ENUM);
 289
 290         /* For a local master announce the workgroup name is the destination name. */
 291
 292         if ((work = find_workgroup_on_subnet(subrec, work_name))==NULL) {
 293                 /* Don't bother adding if it's a local master release announce. */
 294                 if(servertype == 0)
 295                         goto done;
 296
 297                 /* We have no record of this workgroup. Add it. */
 298                 if((work = create_workgroup_on_subnet(subrec, work_name, ttl))==NULL)
 299                         goto done;
 300         }
 301
 302         /* If we think we're the local master browser for this workgroup,
 303                 we should never have got this packet. We don't see our own
 304                 packets.
 305         */
 306         if(AM_LOCAL_MASTER_BROWSER(work)) {
 307                 DEBUG(0,("process_local_master_announce: Server %s at IP %s is announcing itself as \
 308 a local master browser for workgroup %s and we think we are master. Forcing election.\n",
 309                         server_name, inet_ntoa(p->ip), work_name));
 310
 311                 /* Samba nmbd versions 1.9.17 to 1.9.17p4 have a bug in that when
 312                  they have become a local master browser once, they will never
 313                  stop sending local master announcements. To fix this we send
 314                  them a reset browser packet, with level 0x2 on the __SAMBA__
 315                  name that only they should be listening to. */
 316
 317                 send_browser_reset( 0x2, "__SAMBA__" , 0x20, p->ip);
 318
 319                 /* We should demote ourself and force an election. */
 320
 321                 unbecome_local_master_browser( subrec, work, True);
 322
 323                 /* The actual election requests are handled in nmbd_election.c */
 324                 goto done;
 325         }
 326
 327         /* Find the server record on this workgroup. If it doesn't exist, add it. */
 328
 329         if(servertype != 0) {
 330                 if((servrec = find_server_in_workgroup( work, server_name))==NULL) {
 331                         /* If this server is not already in the workgroup, add it. */
 332                         create_server_on_workgroup(work, server_name,
 333                                 servertype|SV_TYPE_LOCAL_LIST_ONLY,
 334                                 ttl, comment);
 335                 } else {
 336                         /* Update the record. */
 337                         servrec->serv.type = servertype|SV_TYPE_LOCAL_LIST_ONLY;
 338                         update_server_ttl(servrec, ttl);
 339                         fstrcpy(servrec->serv.comment,comment);
 340                 }
 341
 342                 set_workgroup_local_master_browser_name( work, server_name );
 343         } else {
 344                 /*
 345                  * This server is announcing it is going down. Remove it from the
 346                  * workgroup.
 347                  */
 348                 if(!is_myname(server_name) && (work != NULL) &&
 349                                 ((servrec = find_server_in_workgroup( work, server_name))!=NULL)) {
 350                         remove_server_from_workgroup( work, servrec);
 351                 }
 352         }
 353
 354         subrec->work_changed = True;
 355 done:
 356
 357         END_PROFILE(local_master_announce);
 358 }
 359
 360 /*******************************************************************
 361   Process a domain master announcement frame.
 362   Domain master browsers receive these from local masters. The Domain
 363   master should then issue a sync with the local master, asking for
 364   that machines local server list.
 365 ******************************************************************/
 366
 367 void process_master_browser_announce(struct subnet_record *subrec,
 368                                      struct packet_struct *p,char *buf)
 369 {
 370         unstring local_master_name;
 371         struct work_record *work;
 372         struct browse_cache_record *browrec;
 373
 374         START_PROFILE(master_browser_announce);
 375
 376         pull_ascii_nstring(local_master_name,sizeof(local_master_name),buf);
 377
 378         DEBUG(3,("process_master_browser_announce: Local master announce from %s IP %s.\n",
 379                 local_master_name, inet_ntoa(p->ip)));
 380
 381         if (!lp_domain_master()) {
 382                 DEBUG(0,("process_master_browser_announce: Not configured as domain \
 383 master - ignoring master announce.\n"));
 384                 goto done;
 385         }
 386
 387         if((work = find_workgroup_on_subnet(subrec, lp_workgroup())) == NULL) {
 388                 DEBUG(0,("process_master_browser_announce: Cannot find workgroup %s on subnet %s\n",
 389                         lp_workgroup(), subrec->subnet_name));
 390                 goto done;
 391         }
 392
 393         if(!AM_DOMAIN_MASTER_BROWSER(work)) {
 394                 DEBUG(0,("process_master_browser_announce: Local master announce made to us from \
 395 %s IP %s and we are not a domain master browser.\n", local_master_name, inet_ntoa(p->ip)));
 396                 goto done;
 397         }
 398
 399         /* Add this host as a local master browser entry on the browse lists.
 400                 This causes a sync request to be made to it at a later date.
 401         */
 402
 403         if((browrec = find_browser_in_lmb_cache( local_master_name )) == NULL) {
 404                 /* Add it. */
 405                 create_browser_in_lmb_cache( work->work_group, local_master_name, p->ip);
 406         } else {
 407                 update_browser_death_time(browrec);
 408         }
 409
 410 done:
 411
 412         END_PROFILE(master_browser_announce);
 413 }
 414
 415 /*******************************************************************
 416   Process an incoming LanMan host announcement packet.
 417 *******************************************************************/
 418
 419 void process_lm_host_announce(struct subnet_record *subrec, struct packet_struct *p, char *buf)
 420 {
 421         struct dgram_packet *dgram = &p->packet.dgram;
 422         uint32 servertype = IVAL(buf,1);
 423         int osmajor=CVAL(buf,5);           /* major version of node software */
 424         int osminor=CVAL(buf,6);           /* minor version of node software */
 425         int ttl = SVAL(buf,7);
 426         unstring announce_name;
 427         struct work_record *work;
 428         struct server_record *servrec;
 429         unstring work_name;
 430         unstring source_name;
 431         fstring comment;
 432         char *s = buf+9;
 433
 434         START_PROFILE(lm_host_announce);
 435         s = skip_string(s,1);
 436         pull_ascii(comment, s, sizeof(fstring), 43, STR_TERMINATE);
 437
 438         pull_ascii_nstring(announce_name,sizeof(announce_name),buf+9);
 439         pull_ascii_nstring(source_name,sizeof(source_name),dgram->source_name.name);
 440         /* For a LanMan host announce the workgroup name is the destination name. */
 441         pull_ascii_nstring(work_name,sizeof(work_name),dgram->dest_name.name);
 442
 443         DEBUG(3,("process_lm_host_announce: LM Announcement from %s IP %s to \
 444 %s for server %s.\n", nmb_namestr(&dgram->source_name), inet_ntoa(p->ip),
 445                 nmb_namestr(&dgram->dest_name),announce_name));
 446
 447         DEBUG(5,("process_lm_host_announce: os=(%d,%d) ttl=%d server type=%08x comment=%s\n",
 448                 osmajor, osminor, ttl, servertype,comment));
 449
 450         if ((osmajor < 36) || (osmajor > 38) || (osminor !=0)) {
 451                 DEBUG(5,("process_lm_host_announce: LM Announcement packet does not \
 452 originate from OS/2 Warp client. Ignoring packet.\n"));
 453                 /* Could have been from a Windows machine (with its LM Announce enabled),
 454                         or a Samba server. Then don't disrupt the current browse list. */
 455                 goto done;
 456         }
 457
 458         /* Filter servertype to remove impossible bits. */
 459         servertype &= ~(SV_TYPE_LOCAL_LIST_ONLY|SV_TYPE_DOMAIN_ENUM);
 460
 461         /* A LanMan host announcement must be sent to the name WORKGROUP<00>. */
 462         if(dgram->dest_name.name_type != 0x00) {
 463                 DEBUG(2,("process_lm_host_announce: incorrect name type for destination from IP %s \
 464 (was %02x) should be 0x00. Allowing packet anyway.\n",
 465                         inet_ntoa(p->ip), dgram->dest_name.name_type));
 466                 /* Change it so it was. */
 467                 dgram->dest_name.name_type = 0x00;
 468         }
 469
 470         /*
 471          * Syntax servers version 5.1 send HostAnnounce packets to
 472          * *THE WRONG NAME*. They send to LOCAL_MASTER_BROWSER_NAME<00>
 473          * instead of WORKGROUP<1d> name. So to fix this we check if
 474          * the workgroup name is our own name, and if so change it
 475          * to be our primary workgroup name. This code is probably
 476          * not needed in the LanMan announce code, but it won't hurt.
 477          */
 478
 479         if(strequal(work_name, global_myname()))
 480                 unstrcpy(work_name,lp_workgroup());
 481
 482         /*
 483          * We are being very agressive here in adding a workgroup
 484          * name on the basis of a host announcing itself as being
 485          * in that workgroup. Maybe we should wait for the workgroup
 486          * announce instead ? JRA.
 487          */
 488
 489         work = find_workgroup_on_subnet(subrec, work_name);
 490
 491         if(servertype != 0) {
 492                 if (work == NULL) {
 493                         /* We have no record of this workgroup. Add it. */
 494                         if((work = create_workgroup_on_subnet(subrec, work_name, ttl))==NULL)
 495                                 goto done;
 496                 }
 497
 498                 if((servrec = find_server_in_workgroup( work, announce_name))==NULL) {
 499                         /* If this server is not already in the workgroup, add it. */
 500                         create_server_on_workgroup(work, announce_name,
 501                                         servertype|SV_TYPE_LOCAL_LIST_ONLY,
 502                                         ttl, comment);
 503                 } else {
 504                         /* Update the record. */
 505                         servrec->serv.type = servertype|SV_TYPE_LOCAL_LIST_ONLY;
 506                         update_server_ttl( servrec, ttl);
 507                         fstrcpy(servrec->serv.comment,comment);
 508                 }
 509         } else {
 510                 /*
 511                  * This server is announcing it is going down. Remove it from the
 512                  * workgroup.
 513                  */
 514                 if(!is_myname(announce_name) && (work != NULL) &&
 515                                 ((servrec = find_server_in_workgroup( work, announce_name))!=NULL)) {
 516                         remove_server_from_workgroup( work, servrec);
 517                 }
 518         }
 519
 520         subrec->work_changed = True;
 521         found_lm_clients = True;
 522
 523 done:
 524
 525         END_PROFILE(lm_host_announce);
 526 }
 527
 528 /****************************************************************************
 529   Send a backup list response.
 530 *****************************************************************************/
 531
 532 static void send_backup_list_response(struct subnet_record *subrec,
 533                                       struct work_record *work,
 534                                       struct nmb_name *send_to_name,
 535                                       unsigned char max_number_requested,
 536                                       uint32 token, struct in_addr sendto_ip,
 537                                       int port)
 538 {
 539         char outbuf[1024];
 540         char *p, *countptr;
 541         unsigned int count = 0;
 542         unstring send_to_namestr;
 543 #if 0
 544   struct server_record *servrec;
 545 #endif
 546         unstring myname;
 547
 548         memset(outbuf,'\0',sizeof(outbuf));
 549
 550         DEBUG(3,("send_backup_list_response: sending backup list for workgroup %s to %s IP %s\n",
 551                 work->work_group, nmb_namestr(send_to_name), inet_ntoa(sendto_ip)));
 552
 553         p = outbuf;
 554
 555         SCVAL(p,0,ANN_GetBackupListResp); /* Backup list response opcode. */
 556         p++;
 557
 558         countptr = p;
 559         p++;
 560
 561         SIVAL(p,0,token); /* The sender's unique info. */
 562         p += 4;
 563
 564         /* We always return at least one name - our own. */
 565         count = 1;
 566         unstrcpy(myname, global_myname());
 567         strupper_m(myname);
 568         myname[15]='\0';
 569         push_pstring_base(p, myname, outbuf);
 570
 571         p = skip_string(p,1);
 572
 573         /* Look for backup browsers in this workgroup. */
 574
 575 #if 0
 576   /* we don't currently send become_backup requests so we should never
 577      send any other servers names out as backups for our
 578      workgroup. That's why this is commented out (tridge) */
 579
 580   /*
 581    * NB. Note that the struct work_record here is not neccessarily
 582    * attached to the subnet *subrec.
 583    */
 584
 585   for (servrec = work->serverlist; servrec; servrec = servrec->next)
 586   {
 587     int len = PTR_DIFF(p, outbuf);
 588     if((sizeof(outbuf) - len) < 16)
 589       break;
 590
 591     if(count >= (unsigned int)max_number_requested)
 592       break;
 593
 594     if(strnequal(servrec->serv.name, global_myname(),15))
 595       continue;
 596
 597     if(!(servrec->serv.type & SV_TYPE_BACKUP_BROWSER))
 598       continue;
 599
 600     StrnCpy(p, servrec->serv.name, 15);
 601     strupper_m(p);
 602     count++;
 603
 604     DEBUG(5,("send_backup_list_response: Adding server %s number %d\n",
 605               p, count));
 606
 607     p = skip_string(p,1);
 608   }
 609 #endif
 610
 611         SCVAL(countptr, 0, count);
 612
 613         pull_ascii_nstring(send_to_namestr, sizeof(send_to_namestr), send_to_name->name);
 614
 615         DEBUG(4,("send_backup_list_response: sending response to %s<00> IP %s with %d servers.\n",
 616                 send_to_namestr, inet_ntoa(sendto_ip), count));
 617
 618         send_mailslot(True, BROWSE_MAILSLOT,
 619                 outbuf,PTR_DIFF(p,outbuf),
 620                 global_myname(), 0,
 621                 send_to_namestr,0,
 622                 sendto_ip, subrec->myip, port);
 623 }
 624
 625 /*******************************************************************
 626   Process a send backup list request packet.
 627
 628   A client sends a backup list request to ask for a list of servers on
 629   the net that maintain server lists for a domain. A server is then
 630   chosen from this list to send NetServerEnum commands to to list
 631   available servers.
 632
 633 ********************************************************************/
 634
 635 void process_get_backup_list_request(struct subnet_record *subrec,
 636                                      struct packet_struct *p,char *buf)
 637 {
 638         struct dgram_packet *dgram = &p->packet.dgram;
 639         struct work_record *work;
 640         unsigned char max_number_requested = CVAL(buf,0);
 641         uint32 token = IVAL(buf,1); /* Sender's key index for the workgroup. */
 642         int name_type = dgram->dest_name.name_type;
 643         unstring workgroup_name;
 644         struct subnet_record *search_subrec = subrec;
 645
 646         START_PROFILE(get_backup_list);
 647         pull_ascii_nstring(workgroup_name, sizeof(workgroup_name), dgram->dest_name.name);
 648
 649         DEBUG(3,("process_get_backup_list_request: request from %s IP %s to %s.\n",
 650                 nmb_namestr(&dgram->source_name), inet_ntoa(p->ip),
 651                 nmb_namestr(&dgram->dest_name)));
 652
 653         /* We have to be a master browser, or a domain master browser
 654                 for the requested workgroup. That means it must be our
 655                 workgroup. */
 656
 657         if(strequal(workgroup_name, lp_workgroup()) == False) {
 658                 DEBUG(7,("process_get_backup_list_request: Ignoring announce request for workgroup %s.\n",
 659                         workgroup_name));
 660                 goto done;
 661         }
 662
 663         if((work = find_workgroup_on_subnet(search_subrec, workgroup_name)) == NULL) {
 664                 DEBUG(0,("process_get_backup_list_request: Cannot find workgroup %s on \
 665 subnet %s.\n", workgroup_name, search_subrec->subnet_name));
 666                 goto done;
 667         }
 668
 669         /*
 670          * If the packet was sent to WORKGROUP<1b> instead
 671          * of WORKGROUP<1d> then it was unicast to us a domain master
 672          * browser. Change search subrec to unicast.
 673          */
 674
 675         if(name_type == 0x1b) {
 676                 /* We must be a domain master browser in order to
 677                         process this packet. */
 678
 679                 if(!AM_DOMAIN_MASTER_BROWSER(work)) {
 680                         DEBUG(0,("process_get_backup_list_request: domain list requested for workgroup %s \
 681 and I am not a domain master browser.\n", workgroup_name));
 682                         goto done;
 683                 }
 684
 685                 search_subrec = unicast_subnet;
 686         } else if (name_type == 0x1d) {
 687                 /* We must be a local master browser in order to process this packet. */
 688
 689                 if(!AM_LOCAL_MASTER_BROWSER(work)) {
 690                         DEBUG(0,("process_get_backup_list_request: domain list requested for workgroup %s \
 691 and I am not a local master browser.\n", workgroup_name));
 692                         goto done;
 693                 }
 694         } else {
 695                 DEBUG(0,("process_get_backup_list_request: Invalid name type %x - should be 0x1b or 0x1d.\n",
 696                         name_type));
 697                 goto done;
 698         }
 699
 700         send_backup_list_response(subrec, work, &dgram->source_name,
 701                         max_number_requested, token, p->ip, p->port);
 702
 703 done:
 704
 705         END_PROFILE(get_backup_list);
 706 }
 707
 708 /*******************************************************************
 709   Process a reset browser state packet.
 710
 711   Diagnostic packet:
 712   0x1 - Stop being a master browser and become a backup browser.
 713   0x2 - Discard browse lists, stop being a master browser, try again.
 714   0x4 - Stop being a master browser forever.
 715
 716 ******************************************************************/
 717
 718 void process_reset_browser(struct subnet_record *subrec,
 719                                   struct packet_struct *p,char *buf)
 720 {
 721         struct dgram_packet *dgram = &p->packet.dgram;
 722         int state = CVAL(buf,0);
 723         struct subnet_record *sr;
 724
 725         START_PROFILE(reset_browser);
 726
 727         DEBUG(1,("process_reset_browser: received diagnostic browser reset \
 728 request from %s IP %s state=0x%X\n",
 729                 nmb_namestr(&dgram->source_name), inet_ntoa(p->ip), state));
 730
 731         /* Stop being a local master browser on all our broadcast subnets. */
 732         if (state & 0x1) {
 733                 for (sr = FIRST_SUBNET; sr; sr = NEXT_SUBNET_EXCLUDING_UNICAST(sr)) {
 734                         struct work_record *work;
 735                         for (work = sr->workgrouplist; work; work = work->next) {
 736                                 if (AM_LOCAL_MASTER_BROWSER(work))
 737                                         unbecome_local_master_browser(sr, work, True);
 738                         }
 739                 }
 740         }
 741
 742         /* Discard our browse lists. */
 743         if (state & 0x2) {
 744                 /*
 745                  * Calling expire_workgroups_and_servers with a -1
 746                  * time causes all servers not marked with a PERMANENT_TTL
 747                  * on the workgroup lists to be discarded, and all
 748                  * workgroups with empty server lists to be discarded.
 749                  * This means we keep our own server names and workgroup
 750                  * as these have a PERMANENT_TTL.
 751                  */
 752
 753                 expire_workgroups_and_servers(-1);
 754         }
 755
 756         /* Request to stop browsing altogether. */
 757         if (state & 0x4)
 758                 DEBUG(1,("process_reset_browser: ignoring request to stop being a browser.\n"));
 759
 760         END_PROFILE(reset_browser);
 761 }
 762
 763 /*******************************************************************
 764   Process an announcement request packet.
 765   We don't respond immediately, we just check it's a request for
 766   our workgroup and then set the flag telling the announce code
 767   in nmbd_sendannounce.c:announce_my_server_names that an
 768   announcement is needed soon.
 769 ******************************************************************/
 770
 771 void process_announce_request(struct subnet_record *subrec, struct packet_struct *p, char *buf)
 772 {
 773         struct dgram_packet *dgram = &p->packet.dgram;
 774         struct work_record *work;
 775         unstring workgroup_name;
 776
 777         START_PROFILE(announce_request);
 778
 779         pull_ascii_nstring(workgroup_name, sizeof(workgroup_name), dgram->dest_name.name);
 780         DEBUG(3,("process_announce_request: Announce request from %s IP %s to %s.\n",
 781                 nmb_namestr(&dgram->source_name), inet_ntoa(p->ip),
 782                 nmb_namestr(&dgram->dest_name)));
 783
 784         /* We only send announcement requests on our workgroup. */
 785         if(strequal(workgroup_name, lp_workgroup()) == False) {
 786                 DEBUG(7,("process_announce_request: Ignoring announce request for workgroup %s.\n",
 787                         workgroup_name));
 788                 goto done;
 789         }
 790
 791         if((work = find_workgroup_on_subnet(subrec, workgroup_name)) == NULL) {
 792                 DEBUG(0,("process_announce_request: Unable to find workgroup %s on subnet !\n",
 793                         workgroup_name));
 794                 goto done;
 795         }
 796
 797         work->needannounce = True;
 798 done:
 799
 800         END_PROFILE(announce_request);
 801 }
 802
 803 /*******************************************************************
 804   Process a LanMan announcement request packet.
 805   We don't respond immediately, we just check it's a request for
 806   our workgroup and then set the flag telling that we have found
 807   a LanMan client (DOS or OS/2) and that we will have to start
 808   sending LanMan announcements (unless specifically disabled
 809   through the "lm announce" parameter in smb.conf)
 810 ******************************************************************/
 811
 812 void process_lm_announce_request(struct subnet_record *subrec, struct packet_struct *p, char *buf)
 813 {
 814         struct dgram_packet *dgram = &p->packet.dgram;
 815         unstring workgroup_name;
 816
 817         START_PROFILE(lm_announce_request);
 818
 819         pull_ascii_nstring(workgroup_name, sizeof(workgroup_name), dgram->dest_name.name);
 820         DEBUG(3,("process_lm_announce_request: Announce request from %s IP %s to %s.\n",
 821                 nmb_namestr(&dgram->source_name), inet_ntoa(p->ip),
 822                 nmb_namestr(&dgram->dest_name)));
 823
 824         /* We only send announcement requests on our workgroup. */
 825         if(strequal(workgroup_name, lp_workgroup()) == False) {
 826                 DEBUG(7,("process_lm_announce_request: Ignoring announce request for workgroup %s.\n",
 827                         workgroup_name));
 828                 goto done;
 829         }
 830
 831         if(find_workgroup_on_subnet(subrec, workgroup_name) == NULL) {
 832                 DEBUG(0,("process_announce_request: Unable to find workgroup %s on subnet !\n",
 833                         workgroup_name));
 834                 goto done;
 835         }
 836
 837         found_lm_clients = True;
 838
 839 done:
 840
 841         END_PROFILE(lm_announce_request);
 842 }