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 3 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, see <http://www.gnu.org/licenses/>.
  20
  21 */
  22
  23 #include "includes.h"
  24 #include "../librpc/gen_ndr/svcctl.h"
  25 #include "nmbd/nmbd.h"
  26 #include "smbprofile.h"
  27
  28 extern bool found_lm_clients;
  29
  30 #if 0
  31
  32 /* XXXX note: This function is currently unsuitable for use, as it
  33    does not properly check that a server is in a fit state to become
  34    a backup browser before asking it to be one.
  35    The code is left here to be worked on at a later date.
  36 */
  37
  38 /****************************************************************************
  39 Tell a server to become a backup browser
  40 **************************************************************************/
  41
  42 void tell_become_backup(void)
  43 {
  44   struct subnet_record *subrec;
  45   for (subrec = FIRST_SUBNET; subrec; subrec = NEXT_SUBNET_EXCLUDING_UNICAST(subrec))
  46   {
  47     struct work_record *work;
  48     for (work = subrec->workgrouplist; work; work = work->next)
  49     {
  50       struct server_record *servrec;
  51       int num_servers = 0;
  52       int num_backups = 0;
  53
  54       for (servrec = work->serverlist; servrec; servrec = servrec->next)
  55       {
  56         num_servers++;
  57
  58         if (is_myname(servrec->serv.name))
  59           continue;
  60
  61         if (servrec->serv.type & SV_TYPE_BACKUP_BROWSER)
  62         {
  63           num_backups++;
  64           continue;
  65         }
  66
  67         if (servrec->serv.type & SV_TYPE_MASTER_BROWSER)
  68           continue;
  69
  70         if (!(servrec->serv.type & SV_TYPE_POTENTIAL_BROWSER))
  71           continue;
  72
  73         DEBUG(3,("num servers: %d num backups: %d\n",
  74               num_servers, num_backups));
  75
  76         /* make first server a backup server. thereafter make every
  77            tenth server a backup server */
  78         if (num_backups != 0 && (num_servers+9) / num_backups > 10)
  79           continue;
  80
  81         DEBUG(2,("sending become backup to %s %s for %s\n",
  82              servrec->serv.name, inet_ntoa(subrec->bcast_ip),
  83              work->work_group));
  84
  85         /* type 11 request from MYNAME(20) to WG(1e) for SERVER */
  86         do_announce_request(servrec->serv.name, work->work_group,
  87               ANN_BecomeBackup, 0x20, 0x1e, subrec->bcast_ip);
  88       }
  89     }
  90   }
  91 }
  92 #endif
  93
  94 /*******************************************************************
  95   Process an incoming host announcement packet.
  96 *******************************************************************/
  97
  98 void process_host_announce(struct subnet_record *subrec, struct packet_struct *p, const char *buf)
  99 {
 100         struct dgram_packet *dgram = &p->packet.dgram;
 101         int ttl = IVAL(buf,1)/1000;
 102         unstring announce_name;
 103         uint32 servertype = IVAL(buf,23);
 104         fstring comment;
 105         struct work_record *work;
 106         struct server_record *servrec;
 107         unstring work_name;
 108         unstring source_name;
 109
 110         START_PROFILE(host_announce);
 111
 112         pull_ascii_fstring(comment, buf+31);
 113
 114         pull_ascii_nstring(announce_name, sizeof(announce_name), buf+5);
 115         pull_ascii_nstring(source_name, sizeof(source_name), dgram->source_name.name);
 116
 117         DEBUG(3,("process_host_announce: from %s<%02x> IP %s to \
 118 %s for server %s.\n", source_name, source_name[15], inet_ntoa(p->ip),
 119                         nmb_namestr(&dgram->dest_name),announce_name));
 120
 121         DEBUG(5,("process_host_announce: ttl=%d server type=%08x comment=%s\n",
 122                 ttl, servertype,comment));
 123
 124         /* Filter servertype to remove impossible bits. */
 125         servertype &= ~(SV_TYPE_LOCAL_LIST_ONLY|SV_TYPE_DOMAIN_ENUM);
 126
 127         /* A host announcement must be sent to the name WORKGROUP<1d>. */
 128         if(dgram->dest_name.name_type != 0x1d) {
 129                 DEBUG(2,("process_host_announce: incorrect name type for destination from IP %s \
 130 (was %02x) should be 0x1d. Allowing packet anyway.\n",
 131                         inet_ntoa(p->ip), dgram->dest_name.name_type));
 132                 /* Change it so it was. */
 133                 dgram->dest_name.name_type = 0x1d;
 134         }
 135
 136         /* For a host announce the workgroup name is the destination name. */
 137         pull_ascii_nstring(work_name, sizeof(work_name), dgram->dest_name.name);
 138
 139         /*
 140          * Syntax servers version 5.1 send HostAnnounce packets to
 141          * *THE WRONG NAME*. They send to LOCAL_MASTER_BROWSER_NAME<00>
 142          * instead of WORKGROUP<1d> name. So to fix this we check if
 143          * the workgroup name is our own name, and if so change it
 144          * to be our primary workgroup name.
 145          */
 146
 147         if(strequal(work_name, lp_netbios_name()))
 148                 unstrcpy(work_name,lp_workgroup());
 149
 150         /*
 151          * We are being very agressive here in adding a workgroup
 152          * name on the basis of a host announcing itself as being
 153          * in that workgroup. Maybe we should wait for the workgroup
 154          * announce instead ? JRA.
 155          */
 156
 157         work = find_workgroup_on_subnet(subrec, work_name);
 158
 159         if(servertype != 0) {
 160                 if (work ==NULL ) {
 161                         /* We have no record of this workgroup. Add it. */
 162                         if((work = create_workgroup_on_subnet(subrec, work_name, ttl))==NULL)
 163                                 goto done;
 164                 }
 165
 166                 if((servrec = find_server_in_workgroup( work, announce_name))==NULL) {
 167                         /* If this server is not already in the workgroup, add it. */
 168                         create_server_on_workgroup(work, announce_name,
 169                                 servertype|SV_TYPE_LOCAL_LIST_ONLY,
 170                                 ttl, comment);
 171                 } else {
 172                         /* Update the record. */
 173                         servrec->serv.type = servertype|SV_TYPE_LOCAL_LIST_ONLY;
 174                         update_server_ttl( servrec, ttl);
 175                         strlcpy(servrec->serv.comment,comment,sizeof(servrec->serv.comment));
 176                 }
 177         } else {
 178                 /*
 179                  * This server is announcing it is going down. Remove it from the
 180                  * workgroup.
 181                  */
 182                 if(!is_myname(announce_name) && (work != NULL) &&
 183                                 ((servrec = find_server_in_workgroup( work, announce_name))!=NULL)) {
 184                         remove_server_from_workgroup( work, servrec);
 185                 }
 186         }
 187
 188         subrec->work_changed = True;
 189 done:
 190
 191         END_PROFILE(host_announce);
 192 }
 193
 194 /*******************************************************************
 195   Process an incoming WORKGROUP announcement packet.
 196 *******************************************************************/
 197
 198 void process_workgroup_announce(struct subnet_record *subrec, struct packet_struct *p, const char *buf)
 199 {
 200         struct dgram_packet *dgram = &p->packet.dgram;
 201         int ttl = IVAL(buf,1)/1000;
 202         unstring workgroup_announce_name;
 203         unstring master_name;
 204         uint32 servertype = IVAL(buf,23);
 205         struct work_record *work;
 206         unstring source_name;
 207         unstring dest_name;
 208
 209         START_PROFILE(workgroup_announce);
 210
 211         pull_ascii_nstring(workgroup_announce_name,sizeof(workgroup_announce_name),buf+5);
 212         pull_ascii_nstring(master_name,sizeof(master_name),buf+31);
 213         pull_ascii_nstring(source_name,sizeof(source_name),dgram->source_name.name);
 214         pull_ascii_nstring(dest_name,sizeof(dest_name),dgram->dest_name.name);
 215
 216         DEBUG(3,("process_workgroup_announce: from %s<%02x> IP %s to \
 217 %s for workgroup %s.\n", source_name, source_name[15], inet_ntoa(p->ip),
 218                         nmb_namestr(&dgram->dest_name),workgroup_announce_name));
 219
 220         DEBUG(5,("process_workgroup_announce: ttl=%d server type=%08x master browser=%s\n",
 221                 ttl, servertype, master_name));
 222
 223         /* Workgroup announcements must only go to the MSBROWSE name. */
 224         if (!strequal(dest_name, MSBROWSE) || (dgram->dest_name.name_type != 0x1)) {
 225                 DEBUG(0,("process_workgroup_announce: from IP %s should be to __MSBROWSE__<0x01> not %s\n",
 226                         inet_ntoa(p->ip), nmb_namestr(&dgram->dest_name)));
 227                 goto done;
 228         }
 229
 230         if ((work = find_workgroup_on_subnet(subrec, workgroup_announce_name))==NULL) {
 231                 /* We have no record of this workgroup. Add it. */
 232                 if((work = create_workgroup_on_subnet(subrec, workgroup_announce_name, ttl))==NULL)
 233                         goto done;
 234         } else {
 235                 /* Update the workgroup death_time. */
 236                 update_workgroup_ttl(work, ttl);
 237         }
 238
 239         if(*work->local_master_browser_name == '\0') {
 240                 /* Set the master browser name. */
 241                 set_workgroup_local_master_browser_name( work, master_name );
 242         }
 243
 244         subrec->work_changed = True;
 245
 246 done:
 247
 248         END_PROFILE(workgroup_announce);
 249 }
 250
 251 /*******************************************************************
 252   Process an incoming local master browser announcement packet.
 253 *******************************************************************/
 254
 255 void process_local_master_announce(struct subnet_record *subrec, struct packet_struct *p, const char *buf)
 256 {
 257         struct dgram_packet *dgram = &p->packet.dgram;
 258         int ttl = IVAL(buf,1)/1000;
 259         unstring server_name;
 260         uint32 servertype = IVAL(buf,23);
 261         fstring comment;
 262         unstring work_name;
 263         struct work_record *work = NULL;
 264         struct server_record *servrec;
 265         unstring source_name;
 266
 267         START_PROFILE(local_master_announce);
 268
 269         pull_ascii_nstring(server_name,sizeof(server_name),buf+5);
 270         pull_ascii_fstring(comment, buf+31);
 271         pull_ascii_nstring(source_name, sizeof(source_name), dgram->source_name.name);
 272         pull_ascii_nstring(work_name, sizeof(work_name), dgram->dest_name.name);
 273
 274         DEBUG(3,("process_local_master_announce: from %s<%02x> IP %s to \
 275 %s for server %s.\n", source_name, source_name[15], inet_ntoa(p->ip),
 276                 nmb_namestr(&dgram->dest_name),server_name));
 277
 278         DEBUG(5,("process_local_master_announce: ttl=%d server type=%08x comment=%s\n",
 279                 ttl, servertype, comment));
 280
 281         /* A local master announcement must be sent to the name WORKGROUP<1e>. */
 282         if(dgram->dest_name.name_type != 0x1e) {
 283                 DEBUG(0,("process_local_master_announce: incorrect name type for destination from IP %s \
 284 (was %02x) should be 0x1e. Ignoring packet.\n",
 285                         inet_ntoa(p->ip), dgram->dest_name.name_type));
 286                 goto done;
 287         }
 288
 289         /* Filter servertype to remove impossible bits. */
 290         servertype &= ~(SV_TYPE_LOCAL_LIST_ONLY|SV_TYPE_DOMAIN_ENUM);
 291
 292         /* For a local master announce the workgroup name is the destination name. */
 293
 294         if ((work = find_workgroup_on_subnet(subrec, work_name))==NULL) {
 295                 /* Don't bother adding if it's a local master release announce. */
 296                 if(servertype == 0)
 297                         goto done;
 298
 299                 /* We have no record of this workgroup. Add it. */
 300                 if((work = create_workgroup_on_subnet(subrec, work_name, ttl))==NULL)
 301                         goto done;
 302         }
 303
 304         /* If we think we're the local master browser for this workgroup,
 305                 we should never have got this packet. We don't see our own
 306                 packets.
 307         */
 308         if(AM_LOCAL_MASTER_BROWSER(work)) {
 309                 DEBUG(0,("process_local_master_announce: Server %s at IP %s is announcing itself as \
 310 a local master browser for workgroup %s and we think we are master. Forcing election.\n",
 311                         server_name, inet_ntoa(p->ip), work_name));
 312
 313                 /* Samba nmbd versions 1.9.17 to 1.9.17p4 have a bug in that when
 314                  they have become a local master browser once, they will never
 315                  stop sending local master announcements. To fix this we send
 316                  them a reset browser packet, with level 0x2 on the __SAMBA__
 317                  name that only they should be listening to. */
 318
 319                 send_browser_reset( 0x2, "__SAMBA__" , 0x20, p->ip);
 320
 321                 /* We should demote ourself and force an election. */
 322
 323                 unbecome_local_master_browser( subrec, work, True);
 324
 325                 /* The actual election requests are handled in nmbd_election.c */
 326                 goto done;
 327         }
 328
 329         /* Find the server record on this workgroup. If it doesn't exist, add it. */
 330
 331         if(servertype != 0) {
 332                 if((servrec = find_server_in_workgroup( work, server_name))==NULL) {
 333                         /* If this server is not already in the workgroup, add it. */
 334                         create_server_on_workgroup(work, server_name,
 335                                 servertype|SV_TYPE_LOCAL_LIST_ONLY,
 336                                 ttl, comment);
 337                 } else {
 338                         /* Update the record. */
 339                         servrec->serv.type = servertype|SV_TYPE_LOCAL_LIST_ONLY;
 340                         update_server_ttl(servrec, ttl);
 341                         strlcpy(servrec->serv.comment,comment,sizeof(servrec->serv.comment));
 342                 }
 343
 344                 set_workgroup_local_master_browser_name( work, server_name );
 345         } else {
 346                 /*
 347                  * This server is announcing it is going down. Remove it from the
 348                  * workgroup.
 349                  */
 350                 if(!is_myname(server_name) &&
 351                                 ((servrec = find_server_in_workgroup( work, server_name))!=NULL)) {
 352                         remove_server_from_workgroup( work, servrec);
 353                 }
 354         }
 355
 356         subrec->work_changed = True;
 357 done:
 358
 359         END_PROFILE(local_master_announce);
 360 }
 361
 362 /*******************************************************************
 363   Process a domain master announcement frame.
 364   Domain master browsers receive these from local masters. The Domain
 365   master should then issue a sync with the local master, asking for
 366   that machines local server list.
 367 ******************************************************************/
 368
 369 void process_master_browser_announce(struct subnet_record *subrec,
 370                                      struct packet_struct *p,const char *buf)
 371 {
 372         unstring local_master_name;
 373         struct work_record *work;
 374         struct browse_cache_record *browrec;
 375
 376         START_PROFILE(master_browser_announce);
 377
 378         pull_ascii_nstring(local_master_name,sizeof(local_master_name),buf);
 379
 380         DEBUG(3,("process_master_browser_announce: Local master announce from %s IP %s.\n",
 381                 local_master_name, inet_ntoa(p->ip)));
 382
 383         if (!lp_domain_master()) {
 384                 DEBUG(0,("process_master_browser_announce: Not configured as domain \
 385 master - ignoring master announce.\n"));
 386                 goto done;
 387         }
 388
 389         if((work = find_workgroup_on_subnet(subrec, lp_workgroup())) == NULL) {
 390                 DEBUG(0,("process_master_browser_announce: Cannot find workgroup %s on subnet %s\n",
 391                         lp_workgroup(), subrec->subnet_name));
 392                 goto done;
 393         }
 394
 395         if(!AM_DOMAIN_MASTER_BROWSER(work)) {
 396                 DEBUG(0,("process_master_browser_announce: Local master announce made to us from \
 397 %s IP %s and we are not a domain master browser.\n", local_master_name, inet_ntoa(p->ip)));
 398                 goto done;
 399         }
 400
 401         /* Add this host as a local master browser entry on the browse lists.
 402                 This causes a sync request to be made to it at a later date.
 403         */
 404
 405         if((browrec = find_browser_in_lmb_cache( local_master_name )) == NULL) {
 406                 /* Add it. */
 407                 create_browser_in_lmb_cache( work->work_group, local_master_name, p->ip);
 408         } else {
 409                 update_browser_death_time(browrec);
 410         }
 411
 412 done:
 413
 414         END_PROFILE(master_browser_announce);
 415 }
 416
 417 /*******************************************************************
 418   Process an incoming LanMan host announcement packet.
 419 *******************************************************************/
 420
 421 void process_lm_host_announce(struct subnet_record *subrec, struct packet_struct *p, const char *buf, int len)
 422 {
 423         struct dgram_packet *dgram = &p->packet.dgram;
 424         uint32 servertype = IVAL(buf,1);
 425         int osmajor=CVAL(buf,5);           /* major version of node software */
 426         int osminor=CVAL(buf,6);           /* minor version of node software */
 427         int ttl = SVAL(buf,7);
 428         unstring announce_name;
 429         struct work_record *work;
 430         struct server_record *servrec;
 431         unstring work_name;
 432         unstring source_name;
 433         fstring comment;
 434         char *s = get_safe_str_ptr(buf,len,discard_const_p(char, buf),9);
 435
 436         START_PROFILE(lm_host_announce);
 437         if (!s) {
 438                 goto done;
 439         }
 440         s = skip_string(buf,len,s);
 441         if (!s) {
 442                 goto done;
 443         }
 444         pull_ascii(comment, s, sizeof(fstring), 43, STR_TERMINATE);
 445
 446         pull_ascii_nstring(announce_name,sizeof(announce_name),buf+9);
 447         pull_ascii_nstring(source_name,sizeof(source_name),dgram->source_name.name);
 448         /* For a LanMan host announce the workgroup name is the destination name. */
 449         pull_ascii_nstring(work_name,sizeof(work_name),dgram->dest_name.name);
 450
 451         DEBUG(3,("process_lm_host_announce: LM Announcement from %s IP %s to \
 452 %s for server %s.\n", nmb_namestr(&dgram->source_name), inet_ntoa(p->ip),
 453                 nmb_namestr(&dgram->dest_name),announce_name));
 454
 455         DEBUG(5,("process_lm_host_announce: os=(%d,%d) ttl=%d server type=%08x comment=%s\n",
 456                 osmajor, osminor, ttl, servertype,comment));
 457
 458         if ((osmajor < 36) || (osmajor > 38) || (osminor !=0)) {
 459                 DEBUG(5,("process_lm_host_announce: LM Announcement packet does not \
 460 originate from OS/2 Warp client. Ignoring packet.\n"));
 461                 /* Could have been from a Windows machine (with its LM Announce enabled),
 462                         or a Samba server. Then don't disrupt the current browse list. */
 463                 goto done;
 464         }
 465
 466         /* Filter servertype to remove impossible bits. */
 467         servertype &= ~(SV_TYPE_LOCAL_LIST_ONLY|SV_TYPE_DOMAIN_ENUM);
 468
 469         /* A LanMan host announcement must be sent to the name WORKGROUP<00>. */
 470         if(dgram->dest_name.name_type != 0x00) {
 471                 DEBUG(2,("process_lm_host_announce: incorrect name type for destination from IP %s \
 472 (was %02x) should be 0x00. Allowing packet anyway.\n",
 473                         inet_ntoa(p->ip), dgram->dest_name.name_type));
 474                 /* Change it so it was. */
 475                 dgram->dest_name.name_type = 0x00;
 476         }
 477
 478         /*
 479          * Syntax servers version 5.1 send HostAnnounce packets to
 480          * *THE WRONG NAME*. They send to LOCAL_MASTER_BROWSER_NAME<00>
 481          * instead of WORKGROUP<1d> name. So to fix this we check if
 482          * the workgroup name is our own name, and if so change it
 483          * to be our primary workgroup name. This code is probably
 484          * not needed in the LanMan announce code, but it won't hurt.
 485          */
 486
 487         if(strequal(work_name, lp_netbios_name()))
 488                 unstrcpy(work_name,lp_workgroup());
 489
 490         /*
 491          * We are being very agressive here in adding a workgroup
 492          * name on the basis of a host announcing itself as being
 493          * in that workgroup. Maybe we should wait for the workgroup
 494          * announce instead ? JRA.
 495          */
 496
 497         work = find_workgroup_on_subnet(subrec, work_name);
 498
 499         if(servertype != 0) {
 500                 if (work == NULL) {
 501                         /* We have no record of this workgroup. Add it. */
 502                         if((work = create_workgroup_on_subnet(subrec, work_name, ttl))==NULL)
 503                                 goto done;
 504                 }
 505
 506                 if((servrec = find_server_in_workgroup( work, announce_name))==NULL) {
 507                         /* If this server is not already in the workgroup, add it. */
 508                         create_server_on_workgroup(work, announce_name,
 509                                         servertype|SV_TYPE_LOCAL_LIST_ONLY,
 510                                         ttl, comment);
 511                 } else {
 512                         /* Update the record. */
 513                         servrec->serv.type = servertype|SV_TYPE_LOCAL_LIST_ONLY;
 514                         update_server_ttl( servrec, ttl);
 515                         strlcpy(servrec->serv.comment,comment,sizeof(servrec->serv.comment));
 516                 }
 517         } else {
 518                 /*
 519                  * This server is announcing it is going down. Remove it from the
 520                  * workgroup.
 521                  */
 522                 if(!is_myname(announce_name) && (work != NULL) &&
 523                                 ((servrec = find_server_in_workgroup( work, announce_name))!=NULL)) {
 524                         remove_server_from_workgroup( work, servrec);
 525                 }
 526         }
 527
 528         subrec->work_changed = True;
 529         found_lm_clients = True;
 530
 531 done:
 532
 533         END_PROFILE(lm_host_announce);
 534 }
 535
 536 /****************************************************************************
 537   Send a backup list response.
 538 *****************************************************************************/
 539
 540 static void send_backup_list_response(struct subnet_record *subrec,
 541                                       struct work_record *work,
 542                                       struct nmb_name *send_to_name,
 543                                       unsigned char max_number_requested,
 544                                       uint32 token, struct in_addr sendto_ip,
 545                                       int port)
 546 {
 547         char outbuf[1024];
 548         char *p, *countptr;
 549         unsigned int count = 0;
 550         unstring send_to_namestr;
 551 #if 0
 552   struct server_record *servrec;
 553 #endif
 554         unstring myname;
 555
 556         memset(outbuf,'\0',sizeof(outbuf));
 557
 558         DEBUG(3,("send_backup_list_response: sending backup list for workgroup %s to %s IP %s\n",
 559                 work->work_group, nmb_namestr(send_to_name), inet_ntoa(sendto_ip)));
 560
 561         p = outbuf;
 562
 563         SCVAL(p,0,ANN_GetBackupListResp); /* Backup list response opcode. */
 564         p++;
 565
 566         countptr = p;
 567         p++;
 568
 569         SIVAL(p,0,token); /* The sender's unique info. */
 570         p += 4;
 571
 572         /* We always return at least one name - our own. */
 573         count = 1;
 574         unstrcpy(myname, lp_netbios_name());
 575         if (!strupper_m(myname)) {
 576                 DEBUG(4,("strupper_m %s failed\n", myname));
 577                 return;
 578         }
 579         myname[15]='\0';
 580         push_ascii(p, myname, sizeof(outbuf)-PTR_DIFF(p,outbuf)-1, STR_TERMINATE);
 581
 582         p = skip_string(outbuf,sizeof(outbuf),p);
 583
 584         /* Look for backup browsers in this workgroup. */
 585
 586 #if 0
 587   /* we don't currently send become_backup requests so we should never
 588      send any other servers names out as backups for our
 589      workgroup. That's why this is commented out (tridge) */
 590
 591   /*
 592    * NB. Note that the struct work_record here is not neccessarily
 593    * attached to the subnet *subrec.
 594    */
 595
 596   for (servrec = work->serverlist; servrec; servrec = servrec->next)
 597   {
 598     int len = PTR_DIFF(p, outbuf);
 599     if((sizeof(outbuf) - len) < 16)
 600       break;
 601
 602     if(count >= (unsigned int)max_number_requested)
 603       break;
 604
 605     if(strnequal(servrec->serv.name, lp_netbios_name(),15))
 606       continue;
 607
 608     if(!(servrec->serv.type & SV_TYPE_BACKUP_BROWSER))
 609       continue;
 610
 611     StrnCpy(p, servrec->serv.name, 15);
 612     strupper_m(p);
 613     count++;
 614
 615     DEBUG(5,("send_backup_list_response: Adding server %s number %d\n",
 616               p, count));
 617
 618     p = skip_string(outbuf,sizeof(outbuf),p);
 619   }
 620 #endif
 621
 622         SCVAL(countptr, 0, count);
 623
 624         pull_ascii_nstring(send_to_namestr, sizeof(send_to_namestr), send_to_name->name);
 625
 626         DEBUG(4,("send_backup_list_response: sending response to %s<00> IP %s with %d servers.\n",
 627                 send_to_namestr, inet_ntoa(sendto_ip), count));
 628
 629         send_mailslot(True, BROWSE_MAILSLOT,
 630                 outbuf,PTR_DIFF(p,outbuf),
 631                 lp_netbios_name(), 0,
 632                 send_to_namestr,0,
 633                 sendto_ip, subrec->myip, port);
 634 }
 635
 636 /*******************************************************************
 637   Process a send backup list request packet.
 638
 639   A client sends a backup list request to ask for a list of servers on
 640   the net that maintain server lists for a domain. A server is then
 641   chosen from this list to send NetServerEnum commands to to list
 642   available servers.
 643
 644 ********************************************************************/
 645
 646 void process_get_backup_list_request(struct subnet_record *subrec,
 647                                      struct packet_struct *p,const char *buf)
 648 {
 649         struct dgram_packet *dgram = &p->packet.dgram;
 650         struct work_record *work;
 651         unsigned char max_number_requested = CVAL(buf,0);
 652         uint32 token = IVAL(buf,1); /* Sender's key index for the workgroup. */
 653         int name_type = dgram->dest_name.name_type;
 654         unstring workgroup_name;
 655         struct subnet_record *search_subrec = subrec;
 656
 657         START_PROFILE(get_backup_list);
 658         pull_ascii_nstring(workgroup_name, sizeof(workgroup_name), dgram->dest_name.name);
 659
 660         DEBUG(3,("process_get_backup_list_request: request from %s IP %s to %s.\n",
 661                 nmb_namestr(&dgram->source_name), inet_ntoa(p->ip),
 662                 nmb_namestr(&dgram->dest_name)));
 663
 664         /* We have to be a master browser, or a domain master browser
 665                 for the requested workgroup. That means it must be our
 666                 workgroup. */
 667
 668         if(strequal(workgroup_name, lp_workgroup()) == False) {
 669                 DEBUG(7,("process_get_backup_list_request: Ignoring announce request for workgroup %s.\n",
 670                         workgroup_name));
 671                 goto done;
 672         }
 673
 674         if((work = find_workgroup_on_subnet(search_subrec, workgroup_name)) == NULL) {
 675                 DEBUG(0,("process_get_backup_list_request: Cannot find workgroup %s on \
 676 subnet %s.\n", workgroup_name, search_subrec->subnet_name));
 677                 goto done;
 678         }
 679
 680         /*
 681          * If the packet was sent to WORKGROUP<1b> instead
 682          * of WORKGROUP<1d> then it was unicast to us a domain master
 683          * browser. Change search subrec to unicast.
 684          */
 685
 686         if(name_type == 0x1b) {
 687                 /* We must be a domain master browser in order to
 688                         process this packet. */
 689
 690                 if(!AM_DOMAIN_MASTER_BROWSER(work)) {
 691                         DEBUG(0,("process_get_backup_list_request: domain list requested for workgroup %s \
 692 and I am not a domain master browser.\n", workgroup_name));
 693                         goto done;
 694                 }
 695
 696                 search_subrec = unicast_subnet;
 697         } else if (name_type == 0x1d) {
 698                 /* We must be a local master browser in order to process this packet. */
 699
 700                 if(!AM_LOCAL_MASTER_BROWSER(work)) {
 701                         DEBUG(0,("process_get_backup_list_request: domain list requested for workgroup %s \
 702 and I am not a local master browser.\n", workgroup_name));
 703                         goto done;
 704                 }
 705         } else {
 706                 DEBUG(0,("process_get_backup_list_request: Invalid name type %x - should be 0x1b or 0x1d.\n",
 707                         name_type));
 708                 goto done;
 709         }
 710
 711         send_backup_list_response(subrec, work, &dgram->source_name,
 712                         max_number_requested, token, p->ip, p->port);
 713
 714 done:
 715
 716         END_PROFILE(get_backup_list);
 717 }
 718
 719 /*******************************************************************
 720   Process a reset browser state packet.
 721
 722   Diagnostic packet:
 723   0x1 - Stop being a master browser and become a backup browser.
 724   0x2 - Discard browse lists, stop being a master browser, try again.
 725   0x4 - Stop being a master browser forever.
 726
 727 ******************************************************************/
 728
 729 void process_reset_browser(struct subnet_record *subrec,
 730                                   struct packet_struct *p,const char *buf)
 731 {
 732         struct dgram_packet *dgram = &p->packet.dgram;
 733         int state = CVAL(buf,0);
 734         struct subnet_record *sr;
 735
 736         START_PROFILE(reset_browser);
 737
 738         DEBUG(1,("process_reset_browser: received diagnostic browser reset \
 739 request from %s IP %s state=0x%X\n",
 740                 nmb_namestr(&dgram->source_name), inet_ntoa(p->ip), state));
 741
 742         /* Stop being a local master browser on all our broadcast subnets. */
 743         if (state & 0x1) {
 744                 for (sr = FIRST_SUBNET; sr; sr = NEXT_SUBNET_EXCLUDING_UNICAST(sr)) {
 745                         struct work_record *work;
 746                         for (work = sr->workgrouplist; work; work = work->next) {
 747                                 if (AM_LOCAL_MASTER_BROWSER(work))
 748                                         unbecome_local_master_browser(sr, work, True);
 749                         }
 750                 }
 751         }
 752
 753         /* Discard our browse lists. */
 754         if (state & 0x2) {
 755                 /*
 756                  * Calling expire_workgroups_and_servers with a -1
 757                  * time causes all servers not marked with a PERMANENT_TTL
 758                  * on the workgroup lists to be discarded, and all
 759                  * workgroups with empty server lists to be discarded.
 760                  * This means we keep our own server names and workgroup
 761                  * as these have a PERMANENT_TTL.
 762                  */
 763
 764                 expire_workgroups_and_servers(-1);
 765         }
 766
 767         /* Request to stop browsing altogether. */
 768         if (state & 0x4)
 769                 DEBUG(1,("process_reset_browser: ignoring request to stop being a browser.\n"));
 770
 771         END_PROFILE(reset_browser);
 772 }
 773
 774 /*******************************************************************
 775   Process an announcement request packet.
 776   We don't respond immediately, we just check it's a request for
 777   our workgroup and then set the flag telling the announce code
 778   in nmbd_sendannounce.c:announce_my_server_names that an
 779   announcement is needed soon.
 780 ******************************************************************/
 781
 782 void process_announce_request(struct subnet_record *subrec, struct packet_struct *p, const char *buf)
 783 {
 784         struct dgram_packet *dgram = &p->packet.dgram;
 785         struct work_record *work;
 786         unstring workgroup_name;
 787
 788         START_PROFILE(announce_request);
 789
 790         pull_ascii_nstring(workgroup_name, sizeof(workgroup_name), dgram->dest_name.name);
 791         DEBUG(3,("process_announce_request: Announce request from %s IP %s to %s.\n",
 792                 nmb_namestr(&dgram->source_name), inet_ntoa(p->ip),
 793                 nmb_namestr(&dgram->dest_name)));
 794
 795         /* We only send announcement requests on our workgroup. */
 796         if(strequal(workgroup_name, lp_workgroup()) == False) {
 797                 DEBUG(7,("process_announce_request: Ignoring announce request for workgroup %s.\n",
 798                         workgroup_name));
 799                 goto done;
 800         }
 801
 802         if((work = find_workgroup_on_subnet(subrec, workgroup_name)) == NULL) {
 803                 DEBUG(0,("process_announce_request: Unable to find workgroup %s on subnet !\n",
 804                         workgroup_name));
 805                 goto done;
 806         }
 807
 808         work->needannounce = True;
 809 done:
 810
 811         END_PROFILE(announce_request);
 812 }
 813
 814 /*******************************************************************
 815   Process a LanMan announcement request packet.
 816   We don't respond immediately, we just check it's a request for
 817   our workgroup and then set the flag telling that we have found
 818   a LanMan client (DOS or OS/2) and that we will have to start
 819   sending LanMan announcements (unless specifically disabled
 820   through the "lm announce" parameter in smb.conf)
 821 ******************************************************************/
 822
 823 void process_lm_announce_request(struct subnet_record *subrec, struct packet_struct *p, const char *buf, int len)
 824 {
 825         struct dgram_packet *dgram = &p->packet.dgram;
 826         unstring workgroup_name;
 827
 828         START_PROFILE(lm_announce_request);
 829
 830         pull_ascii_nstring(workgroup_name, sizeof(workgroup_name), dgram->dest_name.name);
 831         DEBUG(3,("process_lm_announce_request: Announce request from %s IP %s to %s.\n",
 832                 nmb_namestr(&dgram->source_name), inet_ntoa(p->ip),
 833                 nmb_namestr(&dgram->dest_name)));
 834
 835         /* We only send announcement requests on our workgroup. */
 836         if(strequal(workgroup_name, lp_workgroup()) == False) {
 837                 DEBUG(7,("process_lm_announce_request: Ignoring announce request for workgroup %s.\n",
 838                         workgroup_name));
 839                 goto done;
 840         }
 841
 842         if(find_workgroup_on_subnet(subrec, workgroup_name) == NULL) {
 843                 DEBUG(0,("process_announce_request: Unable to find workgroup %s on subnet !\n",
 844                         workgroup_name));
 845                 goto done;
 846         }
 847
 848         found_lm_clients = True;
 849
 850 done:
 851
 852         END_PROFILE(lm_announce_request);
 853 }