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
  27 extern bool found_lm_clients;
  28
  29 #if 0
  30
  31 /* XXXX note: This function is currently unsuitable for use, as it
  32    does not properly check that a server is in a fit state to become
  33    a backup browser before asking it to be one.
  34    The code is left here to be worked on at a later date.
  35 */
  36
  37 /****************************************************************************
  38 Tell a server to become a backup browser
  39 **************************************************************************/
  40
  41 void tell_become_backup(void)
  42 {
  43   struct subnet_record *subrec;
  44   for (subrec = FIRST_SUBNET; subrec; subrec = NEXT_SUBNET_EXCLUDING_UNICAST(subrec))
  45   {
  46     struct work_record *work;
  47     for (work = subrec->workgrouplist; work; work = work->next)
  48     {
  49       struct server_record *servrec;
  50       int num_servers = 0;
  51       int num_backups = 0;
  52
  53       for (servrec = work->serverlist; servrec; servrec = servrec->next)
  54       {
  55         num_servers++;
  56
  57         if (is_myname(servrec->serv.name))
  58           continue;
  59
  60         if (servrec->serv.type & SV_TYPE_BACKUP_BROWSER)
  61         {
  62           num_backups++;
  63           continue;
  64         }
  65
  66         if (servrec->serv.type & SV_TYPE_MASTER_BROWSER)
  67           continue;
  68
  69         if (!(servrec->serv.type & SV_TYPE_POTENTIAL_BROWSER))
  70           continue;
  71
  72         DEBUG(3,("num servers: %d num backups: %d\n",
  73               num_servers, num_backups));
  74
  75         /* make first server a backup server. thereafter make every
  76            tenth server a backup server */
  77         if (num_backups != 0 && (num_servers+9) / num_backups > 10)
  78           continue;
  79
  80         DEBUG(2,("sending become backup to %s %s for %s\n",
  81              servrec->serv.name, inet_ntoa(subrec->bcast_ip),
  82              work->work_group));
  83
  84         /* type 11 request from MYNAME(20) to WG(1e) for SERVER */
  85         do_announce_request(servrec->serv.name, work->work_group,
  86               ANN_BecomeBackup, 0x20, 0x1e, subrec->bcast_ip);
  87       }
  88     }
  89   }
  90 }
  91 #endif
  92
  93 /*******************************************************************
  94   Process an incoming host announcement packet.
  95 *******************************************************************/
  96
  97 void process_host_announce(struct subnet_record *subrec, struct packet_struct *p, const char *buf)
  98 {
  99         struct dgram_packet *dgram = &p->packet.dgram;
 100         int ttl = IVAL(buf,1)/1000;
 101         unstring announce_name;
 102         uint32_t servertype = IVAL(buf,23);
 103         fstring comment;
 104         struct work_record *work;
 105         struct server_record *servrec;
 106         unstring work_name;
 107         unstring source_name;
 108
 109         pull_ascii_fstring(comment, buf+31);
 110
 111         pull_ascii_nstring(announce_name, sizeof(announce_name), buf+5);
 112         pull_ascii_nstring(source_name, sizeof(source_name), dgram->source_name.name);
 113
 114         DEBUG(3,("process_host_announce: from %s<%02x> IP %s to \
 115 %s for server %s.\n", source_name, source_name[15], inet_ntoa(p->ip),
 116                         nmb_namestr(&dgram->dest_name),announce_name));
 117
 118         DEBUG(5,("process_host_announce: ttl=%d server type=%08x comment=%s\n",
 119                 ttl, servertype,comment));
 120
 121         /* Filter servertype to remove impossible bits. */
 122         servertype &= ~(SV_TYPE_LOCAL_LIST_ONLY|SV_TYPE_DOMAIN_ENUM);
 123
 124         /* A host announcement must be sent to the name WORKGROUP<1d>. */
 125         if(dgram->dest_name.name_type != 0x1d) {
 126                 DEBUG(2,("process_host_announce: incorrect name type for destination from IP %s \
 127 (was %02x) should be 0x1d. Allowing packet anyway.\n",
 128                         inet_ntoa(p->ip), dgram->dest_name.name_type));
 129                 /* Change it so it was. */
 130                 dgram->dest_name.name_type = 0x1d;
 131         }
 132
 133         /* For a host announce the workgroup name is the destination name. */
 134         pull_ascii_nstring(work_name, sizeof(work_name), dgram->dest_name.name);
 135
 136         /*
 137          * Syntax servers version 5.1 send HostAnnounce packets to
 138          * *THE WRONG NAME*. They send to LOCAL_MASTER_BROWSER_NAME<00>
 139          * instead of WORKGROUP<1d> name. So to fix this we check if
 140          * the workgroup name is our own name, and if so change it
 141          * to be our primary workgroup name.
 142          */
 143
 144         if(strequal(work_name, lp_netbios_name()))
 145                 unstrcpy(work_name,lp_workgroup());
 146
 147         /*
 148          * We are being very agressive here in adding a workgroup
 149          * name on the basis of a host announcing itself as being
 150          * in that workgroup. Maybe we should wait for the workgroup
 151          * announce instead ? JRA.
 152          */
 153
 154         work = find_workgroup_on_subnet(subrec, work_name);
 155
 156         if(servertype != 0) {
 157                 if (work ==NULL ) {
 158                         /* We have no record of this workgroup. Add it. */
 159                         if((work = create_workgroup_on_subnet(subrec, work_name, ttl))==NULL)
 160                                 goto done;
 161                 }
 162
 163                 if((servrec = find_server_in_workgroup( work, announce_name))==NULL) {
 164                         /* If this server is not already in the workgroup, add it. */
 165                         create_server_on_workgroup(work, announce_name,
 166                                 servertype|SV_TYPE_LOCAL_LIST_ONLY,
 167                                 ttl, comment);
 168                 } else {
 169                         /* Update the record. */
 170                         servrec->serv.type = servertype|SV_TYPE_LOCAL_LIST_ONLY;
 171                         update_server_ttl( servrec, ttl);
 172                         strlcpy(servrec->serv.comment,comment,sizeof(servrec->serv.comment));
 173                 }
 174         } else {
 175                 /*
 176                  * This server is announcing it is going down. Remove it from the
 177                  * workgroup.
 178                  */
 179                 if(!is_myname(announce_name) && (work != NULL) &&
 180                                 ((servrec = find_server_in_workgroup( work, announce_name))!=NULL)) {
 181                         remove_server_from_workgroup( work, servrec);
 182                 }
 183         }
 184
 185         subrec->work_changed = True;
 186 done:
 187         return;
 188 }
 189
 190 /*******************************************************************
 191   Process an incoming WORKGROUP announcement packet.
 192 *******************************************************************/
 193
 194 void process_workgroup_announce(struct subnet_record *subrec, struct packet_struct *p, const char *buf)
 195 {
 196         struct dgram_packet *dgram = &p->packet.dgram;
 197         int ttl = IVAL(buf,1)/1000;
 198         unstring workgroup_announce_name;
 199         unstring master_name;
 200         uint32_t servertype = IVAL(buf,23);
 201         struct work_record *work;
 202         unstring source_name;
 203         unstring dest_name;
 204
 205         pull_ascii_nstring(workgroup_announce_name,sizeof(workgroup_announce_name),buf+5);
 206         pull_ascii_nstring(master_name,sizeof(master_name),buf+31);
 207         pull_ascii_nstring(source_name,sizeof(source_name),dgram->source_name.name);
 208         pull_ascii_nstring(dest_name,sizeof(dest_name),dgram->dest_name.name);
 209
 210         DEBUG(3,("process_workgroup_announce: from %s<%02x> IP %s to \
 211 %s for workgroup %s.\n", source_name, source_name[15], inet_ntoa(p->ip),
 212                         nmb_namestr(&dgram->dest_name),workgroup_announce_name));
 213
 214         DEBUG(5,("process_workgroup_announce: ttl=%d server type=%08x master browser=%s\n",
 215                 ttl, servertype, master_name));
 216
 217         /* Workgroup announcements must only go to the MSBROWSE name. */
 218         if (!strequal(dest_name, MSBROWSE) || (dgram->dest_name.name_type != 0x1)) {
 219                 DEBUG(0,("process_workgroup_announce: from IP %s should be to __MSBROWSE__<0x01> not %s\n",
 220                         inet_ntoa(p->ip), nmb_namestr(&dgram->dest_name)));
 221                 goto done;
 222         }
 223
 224         if ((work = find_workgroup_on_subnet(subrec, workgroup_announce_name))==NULL) {
 225                 /* We have no record of this workgroup. Add it. */
 226                 if((work = create_workgroup_on_subnet(subrec, workgroup_announce_name, ttl))==NULL)
 227                         goto done;
 228         } else {
 229                 /* Update the workgroup death_time. */
 230                 update_workgroup_ttl(work, ttl);
 231         }
 232
 233         if(*work->local_master_browser_name == '\0') {
 234                 /* Set the master browser name. */
 235                 set_workgroup_local_master_browser_name( work, master_name );
 236         }
 237
 238         subrec->work_changed = True;
 239
 240 done:
 241         return;
 242 }
 243
 244 /*******************************************************************
 245   Process an incoming local master browser announcement packet.
 246 *******************************************************************/
 247
 248 void process_local_master_announce(struct subnet_record *subrec, struct packet_struct *p, const char *buf)
 249 {
 250         struct dgram_packet *dgram = &p->packet.dgram;
 251         int ttl = IVAL(buf,1)/1000;
 252         unstring server_name;
 253         uint32_t servertype = IVAL(buf,23);
 254         fstring comment;
 255         unstring work_name;
 256         struct work_record *work = NULL;
 257         struct server_record *servrec;
 258         unstring source_name;
 259
 260         pull_ascii_nstring(server_name,sizeof(server_name),buf+5);
 261         pull_ascii_fstring(comment, buf+31);
 262         pull_ascii_nstring(source_name, sizeof(source_name), dgram->source_name.name);
 263         pull_ascii_nstring(work_name, sizeof(work_name), dgram->dest_name.name);
 264
 265         DEBUG(3,("process_local_master_announce: from %s<%02x> IP %s to \
 266 %s for server %s.\n", source_name, source_name[15], inet_ntoa(p->ip),
 267                 nmb_namestr(&dgram->dest_name),server_name));
 268
 269         DEBUG(5,("process_local_master_announce: ttl=%d server type=%08x comment=%s\n",
 270                 ttl, servertype, comment));
 271
 272         /* A local master announcement must be sent to the name WORKGROUP<1e>. */
 273         if(dgram->dest_name.name_type != 0x1e) {
 274                 DEBUG(0,("process_local_master_announce: incorrect name type for destination from IP %s \
 275 (was %02x) should be 0x1e. Ignoring packet.\n",
 276                         inet_ntoa(p->ip), dgram->dest_name.name_type));
 277                 goto done;
 278         }
 279
 280         /* Filter servertype to remove impossible bits. */
 281         servertype &= ~(SV_TYPE_LOCAL_LIST_ONLY|SV_TYPE_DOMAIN_ENUM);
 282
 283         /* For a local master announce the workgroup name is the destination name. */
 284
 285         if ((work = find_workgroup_on_subnet(subrec, work_name))==NULL) {
 286                 /* Don't bother adding if it's a local master release announce. */
 287                 if(servertype == 0)
 288                         goto done;
 289
 290                 /* We have no record of this workgroup. Add it. */
 291                 if((work = create_workgroup_on_subnet(subrec, work_name, ttl))==NULL)
 292                         goto done;
 293         }
 294
 295         /* If we think we're the local master browser for this workgroup,
 296                 we should never have got this packet. We don't see our own
 297                 packets.
 298         */
 299         if(AM_LOCAL_MASTER_BROWSER(work)) {
 300                 DEBUG(0,("process_local_master_announce: Server %s at IP %s is announcing itself as \
 301 a local master browser for workgroup %s and we think we are master. Forcing election.\n",
 302                         server_name, inet_ntoa(p->ip), work_name));
 303
 304                 /* Samba nmbd versions 1.9.17 to 1.9.17p4 have a bug in that when
 305                  they have become a local master browser once, they will never
 306                  stop sending local master announcements. To fix this we send
 307                  them a reset browser packet, with level 0x2 on the __SAMBA__
 308                  name that only they should be listening to. */
 309
 310                 send_browser_reset( 0x2, "__SAMBA__" , 0x20, p->ip);
 311
 312                 /* We should demote ourself and force an election. */
 313
 314                 unbecome_local_master_browser( subrec, work, True);
 315
 316                 /* The actual election requests are handled in nmbd_election.c */
 317                 goto done;
 318         }
 319
 320         /* Find the server record on this workgroup. If it doesn't exist, add it. */
 321
 322         if(servertype != 0) {
 323                 if((servrec = find_server_in_workgroup( work, server_name))==NULL) {
 324                         /* If this server is not already in the workgroup, add it. */
 325                         create_server_on_workgroup(work, server_name,
 326                                 servertype|SV_TYPE_LOCAL_LIST_ONLY,
 327                                 ttl, comment);
 328                 } else {
 329                         /* Update the record. */
 330                         servrec->serv.type = servertype|SV_TYPE_LOCAL_LIST_ONLY;
 331                         update_server_ttl(servrec, ttl);
 332                         strlcpy(servrec->serv.comment,comment,sizeof(servrec->serv.comment));
 333                 }
 334
 335                 set_workgroup_local_master_browser_name( work, server_name );
 336         } else {
 337                 /*
 338                  * This server is announcing it is going down. Remove it from the
 339                  * workgroup.
 340                  */
 341                 if(!is_myname(server_name) &&
 342                                 ((servrec = find_server_in_workgroup( work, server_name))!=NULL)) {
 343                         remove_server_from_workgroup( work, servrec);
 344                 }
 345         }
 346
 347         subrec->work_changed = True;
 348 done:
 349         return;
 350 }
 351
 352 /*******************************************************************
 353   Process a domain master announcement frame.
 354   Domain master browsers receive these from local masters. The Domain
 355   master should then issue a sync with the local master, asking for
 356   that machines local server list.
 357 ******************************************************************/
 358
 359 void process_master_browser_announce(struct subnet_record *subrec,
 360                                      struct packet_struct *p,const char *buf)
 361 {
 362         unstring local_master_name;
 363         struct work_record *work;
 364         struct browse_cache_record *browrec;
 365
 366         pull_ascii_nstring(local_master_name,sizeof(local_master_name),buf);
 367
 368         DEBUG(3,("process_master_browser_announce: Local master announce from %s IP %s.\n",
 369                 local_master_name, inet_ntoa(p->ip)));
 370
 371         if (!lp_domain_master()) {
 372                 DEBUG(0,("process_master_browser_announce: Not configured as domain \
 373 master - ignoring master announce.\n"));
 374                 goto done;
 375         }
 376
 377         if((work = find_workgroup_on_subnet(subrec, lp_workgroup())) == NULL) {
 378                 DEBUG(0,("process_master_browser_announce: Cannot find workgroup %s on subnet %s\n",
 379                         lp_workgroup(), subrec->subnet_name));
 380                 goto done;
 381         }
 382
 383         if(!AM_DOMAIN_MASTER_BROWSER(work)) {
 384                 DEBUG(0,("process_master_browser_announce: Local master announce made to us from \
 385 %s IP %s and we are not a domain master browser.\n", local_master_name, inet_ntoa(p->ip)));
 386                 goto done;
 387         }
 388
 389         /* Add this host as a local master browser entry on the browse lists.
 390                 This causes a sync request to be made to it at a later date.
 391         */
 392
 393         if((browrec = find_browser_in_lmb_cache( local_master_name )) == NULL) {
 394                 /* Add it. */
 395                 create_browser_in_lmb_cache( work->work_group, local_master_name, p->ip);
 396         } else {
 397                 update_browser_death_time(browrec);
 398         }
 399
 400 done:
 401         return;
 402 }
 403
 404 /*******************************************************************
 405   Process an incoming LanMan host announcement packet.
 406 *******************************************************************/
 407
 408 void process_lm_host_announce(struct subnet_record *subrec, struct packet_struct *p, const char *buf, int len)
 409 {
 410         struct dgram_packet *dgram = &p->packet.dgram;
 411         uint32_t servertype = IVAL(buf,1);
 412         int osmajor=CVAL(buf,5);           /* major version of node software */
 413         int osminor=CVAL(buf,6);           /* minor version of node software */
 414         int ttl = SVAL(buf,7);
 415         unstring announce_name;
 416         struct work_record *work;
 417         struct server_record *servrec;
 418         unstring work_name;
 419         unstring source_name;
 420         fstring comment;
 421         char *s = get_safe_str_ptr(buf,len,discard_const_p(char, buf),9);
 422
 423         if (!s) {
 424                 goto done;
 425         }
 426         s = skip_string(buf,len,s);
 427         if (!s) {
 428                 goto done;
 429         }
 430         pull_ascii(comment, s, sizeof(fstring), 43, STR_TERMINATE);
 431
 432         pull_ascii_nstring(announce_name,sizeof(announce_name),buf+9);
 433         pull_ascii_nstring(source_name,sizeof(source_name),dgram->source_name.name);
 434         /* For a LanMan host announce the workgroup name is the destination name. */
 435         pull_ascii_nstring(work_name,sizeof(work_name),dgram->dest_name.name);
 436
 437         DEBUG(3,("process_lm_host_announce: LM Announcement from %s IP %s to \
 438 %s for server %s.\n", nmb_namestr(&dgram->source_name), inet_ntoa(p->ip),
 439                 nmb_namestr(&dgram->dest_name),announce_name));
 440
 441         DEBUG(5,("process_lm_host_announce: os=(%d,%d) ttl=%d server type=%08x comment=%s\n",
 442                 osmajor, osminor, ttl, servertype,comment));
 443
 444         if ((osmajor < 36) || (osmajor > 38) || (osminor !=0)) {
 445                 DEBUG(5,("process_lm_host_announce: LM Announcement packet does not \
 446 originate from OS/2 Warp client. Ignoring packet.\n"));
 447                 /* Could have been from a Windows machine (with its LM Announce enabled),
 448                         or a Samba server. Then don't disrupt the current browse list. */
 449                 goto done;
 450         }
 451
 452         /* Filter servertype to remove impossible bits. */
 453         servertype &= ~(SV_TYPE_LOCAL_LIST_ONLY|SV_TYPE_DOMAIN_ENUM);
 454
 455         /* A LanMan host announcement must be sent to the name WORKGROUP<00>. */
 456         if(dgram->dest_name.name_type != 0x00) {
 457                 DEBUG(2,("process_lm_host_announce: incorrect name type for destination from IP %s \
 458 (was %02x) should be 0x00. Allowing packet anyway.\n",
 459                         inet_ntoa(p->ip), dgram->dest_name.name_type));
 460                 /* Change it so it was. */
 461                 dgram->dest_name.name_type = 0x00;
 462         }
 463
 464         /*
 465          * Syntax servers version 5.1 send HostAnnounce packets to
 466          * *THE WRONG NAME*. They send to LOCAL_MASTER_BROWSER_NAME<00>
 467          * instead of WORKGROUP<1d> name. So to fix this we check if
 468          * the workgroup name is our own name, and if so change it
 469          * to be our primary workgroup name. This code is probably
 470          * not needed in the LanMan announce code, but it won't hurt.
 471          */
 472
 473         if(strequal(work_name, lp_netbios_name()))
 474                 unstrcpy(work_name,lp_workgroup());
 475
 476         /*
 477          * We are being very agressive here in adding a workgroup
 478          * name on the basis of a host announcing itself as being
 479          * in that workgroup. Maybe we should wait for the workgroup
 480          * announce instead ? JRA.
 481          */
 482
 483         work = find_workgroup_on_subnet(subrec, work_name);
 484
 485         if(servertype != 0) {
 486                 if (work == NULL) {
 487                         /* We have no record of this workgroup. Add it. */
 488                         if((work = create_workgroup_on_subnet(subrec, work_name, ttl))==NULL)
 489                                 goto done;
 490                 }
 491
 492                 if((servrec = find_server_in_workgroup( work, announce_name))==NULL) {
 493                         /* If this server is not already in the workgroup, add it. */
 494                         create_server_on_workgroup(work, announce_name,
 495                                         servertype|SV_TYPE_LOCAL_LIST_ONLY,
 496                                         ttl, comment);
 497                 } else {
 498                         /* Update the record. */
 499                         servrec->serv.type = servertype|SV_TYPE_LOCAL_LIST_ONLY;
 500                         update_server_ttl( servrec, ttl);
 501                         strlcpy(servrec->serv.comment,comment,sizeof(servrec->serv.comment));
 502                 }
 503         } else {
 504                 /*
 505                  * This server is announcing it is going down. Remove it from the
 506                  * workgroup.
 507                  */
 508                 if(!is_myname(announce_name) && (work != NULL) &&
 509                                 ((servrec = find_server_in_workgroup( work, announce_name))!=NULL)) {
 510                         remove_server_from_workgroup( work, servrec);
 511                 }
 512         }
 513
 514         subrec->work_changed = True;
 515         found_lm_clients = True;
 516
 517 done:
 518         return;
 519 }
 520
 521 /****************************************************************************
 522   Send a backup list response.
 523 *****************************************************************************/
 524
 525 static void send_backup_list_response(struct subnet_record *subrec,
 526                                       struct work_record *work,
 527                                       struct nmb_name *send_to_name,
 528                                       unsigned char max_number_requested,
 529                                       uint32_t token, struct in_addr sendto_ip,
 530                                       int port)
 531 {
 532         char outbuf[1024];
 533         char *p, *countptr;
 534         unsigned int count = 0;
 535         unstring send_to_namestr;
 536 #if 0
 537   struct server_record *servrec;
 538 #endif
 539         unstring myname;
 540
 541         memset(outbuf,'\0',sizeof(outbuf));
 542
 543         DEBUG(3,("send_backup_list_response: sending backup list for workgroup %s to %s IP %s\n",
 544                 work->work_group, nmb_namestr(send_to_name), inet_ntoa(sendto_ip)));
 545
 546         p = outbuf;
 547
 548         SCVAL(p,0,ANN_GetBackupListResp); /* Backup list response opcode. */
 549         p++;
 550
 551         countptr = p;
 552         p++;
 553
 554         SIVAL(p,0,token); /* The sender's unique info. */
 555         p += 4;
 556
 557         /* We always return at least one name - our own. */
 558         count = 1;
 559         unstrcpy(myname, lp_netbios_name());
 560         if (!strupper_m(myname)) {
 561                 DEBUG(4,("strupper_m %s failed\n", myname));
 562                 return;
 563         }
 564         myname[15]='\0';
 565         push_ascii(p, myname, sizeof(outbuf)-PTR_DIFF(p,outbuf)-1, STR_TERMINATE);
 566
 567         p = skip_string(outbuf,sizeof(outbuf),p);
 568
 569         /* Look for backup browsers in this workgroup. */
 570
 571 #if 0
 572   /* we don't currently send become_backup requests so we should never
 573      send any other servers names out as backups for our
 574      workgroup. That's why this is commented out (tridge) */
 575
 576   /*
 577    * NB. Note that the struct work_record here is not neccessarily
 578    * attached to the subnet *subrec.
 579    */
 580
 581   for (servrec = work->serverlist; servrec; servrec = servrec->next)
 582   {
 583     int len = PTR_DIFF(p, outbuf);
 584     if((sizeof(outbuf) - len) < 16)
 585       break;
 586
 587     if(count >= (unsigned int)max_number_requested)
 588       break;
 589
 590     if(strnequal(servrec->serv.name, lp_netbios_name(),15))
 591       continue;
 592
 593     if(!(servrec->serv.type & SV_TYPE_BACKUP_BROWSER))
 594       continue;
 595
 596     StrnCpy(p, servrec->serv.name, 15);
 597     strupper_m(p);
 598     count++;
 599
 600     DEBUG(5,("send_backup_list_response: Adding server %s number %d\n",
 601               p, count));
 602
 603     p = skip_string(outbuf,sizeof(outbuf),p);
 604   }
 605 #endif
 606
 607         SCVAL(countptr, 0, count);
 608
 609         pull_ascii_nstring(send_to_namestr, sizeof(send_to_namestr), send_to_name->name);
 610
 611         DEBUG(4,("send_backup_list_response: sending response to %s<00> IP %s with %d servers.\n",
 612                 send_to_namestr, inet_ntoa(sendto_ip), count));
 613
 614         send_mailslot(True, BROWSE_MAILSLOT,
 615                 outbuf,PTR_DIFF(p,outbuf),
 616                 lp_netbios_name(), 0,
 617                 send_to_namestr,0,
 618                 sendto_ip, subrec->myip, port);
 619 }
 620
 621 /*******************************************************************
 622   Process a send backup list request packet.
 623
 624   A client sends a backup list request to ask for a list of servers on
 625   the net that maintain server lists for a domain. A server is then
 626   chosen from this list to send NetServerEnum commands to to list
 627   available servers.
 628
 629 ********************************************************************/
 630
 631 void process_get_backup_list_request(struct subnet_record *subrec,
 632                                      struct packet_struct *p,const char *buf)
 633 {
 634         struct dgram_packet *dgram = &p->packet.dgram;
 635         struct work_record *work;
 636         unsigned char max_number_requested = CVAL(buf,0);
 637         uint32_t token = IVAL(buf,1); /* Sender's key index for the workgroup. */
 638         int name_type = dgram->dest_name.name_type;
 639         unstring workgroup_name;
 640         struct subnet_record *search_subrec = subrec;
 641
 642         pull_ascii_nstring(workgroup_name, sizeof(workgroup_name), dgram->dest_name.name);
 643
 644         DEBUG(3,("process_get_backup_list_request: request from %s IP %s to %s.\n",
 645                 nmb_namestr(&dgram->source_name), inet_ntoa(p->ip),
 646                 nmb_namestr(&dgram->dest_name)));
 647
 648         /* We have to be a master browser, or a domain master browser
 649                 for the requested workgroup. That means it must be our
 650                 workgroup. */
 651
 652         if(strequal(workgroup_name, lp_workgroup()) == False) {
 653                 DEBUG(7,("process_get_backup_list_request: Ignoring announce request for workgroup %s.\n",
 654                         workgroup_name));
 655                 goto done;
 656         }
 657
 658         if((work = find_workgroup_on_subnet(search_subrec, workgroup_name)) == NULL) {
 659                 DEBUG(0,("process_get_backup_list_request: Cannot find workgroup %s on \
 660 subnet %s.\n", workgroup_name, search_subrec->subnet_name));
 661                 goto done;
 662         }
 663
 664         /*
 665          * If the packet was sent to WORKGROUP<1b> instead
 666          * of WORKGROUP<1d> then it was unicast to us a domain master
 667          * browser. Change search subrec to unicast.
 668          */
 669
 670         if(name_type == 0x1b) {
 671                 /* We must be a domain master browser in order to
 672                         process this packet. */
 673
 674                 if(!AM_DOMAIN_MASTER_BROWSER(work)) {
 675                         DEBUG(0,("process_get_backup_list_request: domain list requested for workgroup %s \
 676 and I am not a domain master browser.\n", workgroup_name));
 677                         goto done;
 678                 }
 679
 680                 search_subrec = unicast_subnet;
 681         } else if (name_type == 0x1d) {
 682                 /* We must be a local master browser in order to process this packet. */
 683
 684                 if(!AM_LOCAL_MASTER_BROWSER(work)) {
 685                         DEBUG(0,("process_get_backup_list_request: domain list requested for workgroup %s \
 686 and I am not a local master browser.\n", workgroup_name));
 687                         goto done;
 688                 }
 689         } else {
 690                 DEBUG(0,("process_get_backup_list_request: Invalid name type %x - should be 0x1b or 0x1d.\n",
 691                         name_type));
 692                 goto done;
 693         }
 694
 695         send_backup_list_response(subrec, work, &dgram->source_name,
 696                         max_number_requested, token, p->ip, p->port);
 697
 698 done:
 699         return;
 700 }
 701
 702 /*******************************************************************
 703   Process a reset browser state packet.
 704
 705   Diagnostic packet:
 706   0x1 - Stop being a master browser and become a backup browser.
 707   0x2 - Discard browse lists, stop being a master browser, try again.
 708   0x4 - Stop being a master browser forever.
 709
 710 ******************************************************************/
 711
 712 void process_reset_browser(struct subnet_record *subrec,
 713                                   struct packet_struct *p,const char *buf)
 714 {
 715         struct dgram_packet *dgram = &p->packet.dgram;
 716         int state = CVAL(buf,0);
 717         struct subnet_record *sr;
 718
 719         DEBUG(1,("process_reset_browser: received diagnostic browser reset \
 720 request from %s IP %s state=0x%X\n",
 721                 nmb_namestr(&dgram->source_name), inet_ntoa(p->ip), state));
 722
 723         /* Stop being a local master browser on all our broadcast subnets. */
 724         if (state & 0x1) {
 725                 for (sr = FIRST_SUBNET; sr; sr = NEXT_SUBNET_EXCLUDING_UNICAST(sr)) {
 726                         struct work_record *work;
 727                         for (work = sr->workgrouplist; work; work = work->next) {
 728                                 if (AM_LOCAL_MASTER_BROWSER(work))
 729                                         unbecome_local_master_browser(sr, work, True);
 730                         }
 731                 }
 732         }
 733
 734         /* Discard our browse lists. */
 735         if (state & 0x2) {
 736                 /*
 737                  * Calling expire_workgroups_and_servers with a -1
 738                  * time causes all servers not marked with a PERMANENT_TTL
 739                  * on the workgroup lists to be discarded, and all
 740                  * workgroups with empty server lists to be discarded.
 741                  * This means we keep our own server names and workgroup
 742                  * as these have a PERMANENT_TTL.
 743                  */
 744
 745                 expire_workgroups_and_servers(-1);
 746         }
 747
 748         /* Request to stop browsing altogether. */
 749         if (state & 0x4)
 750                 DEBUG(1,("process_reset_browser: ignoring request to stop being a browser.\n"));
 751 }
 752
 753 /*******************************************************************
 754   Process an announcement request packet.
 755   We don't respond immediately, we just check it's a request for
 756   our workgroup and then set the flag telling the announce code
 757   in nmbd_sendannounce.c:announce_my_server_names that an
 758   announcement is needed soon.
 759 ******************************************************************/
 760
 761 void process_announce_request(struct subnet_record *subrec, struct packet_struct *p, const char *buf)
 762 {
 763         struct dgram_packet *dgram = &p->packet.dgram;
 764         struct work_record *work;
 765         unstring workgroup_name;
 766
 767         pull_ascii_nstring(workgroup_name, sizeof(workgroup_name), dgram->dest_name.name);
 768         DEBUG(3,("process_announce_request: Announce request from %s IP %s to %s.\n",
 769                 nmb_namestr(&dgram->source_name), inet_ntoa(p->ip),
 770                 nmb_namestr(&dgram->dest_name)));
 771
 772         /* We only send announcement requests on our workgroup. */
 773         if(strequal(workgroup_name, lp_workgroup()) == False) {
 774                 DEBUG(7,("process_announce_request: Ignoring announce request for workgroup %s.\n",
 775                         workgroup_name));
 776                 goto done;
 777         }
 778
 779         if((work = find_workgroup_on_subnet(subrec, workgroup_name)) == NULL) {
 780                 DEBUG(0,("process_announce_request: Unable to find workgroup %s on subnet !\n",
 781                         workgroup_name));
 782                 goto done;
 783         }
 784
 785         work->needannounce = True;
 786 done:
 787         return;
 788 }
 789
 790 /*******************************************************************
 791   Process a LanMan announcement request packet.
 792   We don't respond immediately, we just check it's a request for
 793   our workgroup and then set the flag telling that we have found
 794   a LanMan client (DOS or OS/2) and that we will have to start
 795   sending LanMan announcements (unless specifically disabled
 796   through the "lm announce" parameter in smb.conf)
 797 ******************************************************************/
 798
 799 void process_lm_announce_request(struct subnet_record *subrec, struct packet_struct *p, const char *buf, int len)
 800 {
 801         struct dgram_packet *dgram = &p->packet.dgram;
 802         unstring workgroup_name;
 803
 804         pull_ascii_nstring(workgroup_name, sizeof(workgroup_name), dgram->dest_name.name);
 805         DEBUG(3,("process_lm_announce_request: Announce request from %s IP %s to %s.\n",
 806                 nmb_namestr(&dgram->source_name), inet_ntoa(p->ip),
 807                 nmb_namestr(&dgram->dest_name)));
 808
 809         /* We only send announcement requests on our workgroup. */
 810         if(strequal(workgroup_name, lp_workgroup()) == False) {
 811                 DEBUG(7,("process_lm_announce_request: Ignoring announce request for workgroup %s.\n",
 812                         workgroup_name));
 813                 goto done;
 814         }
 815
 816         if(find_workgroup_on_subnet(subrec, workgroup_name) == NULL) {
 817                 DEBUG(0,("process_announce_request: Unable to find workgroup %s on subnet !\n",
 818                         workgroup_name));
 819                 goto done;
 820         }
 821
 822         found_lm_clients = True;
 823
 824 done:
 825         return;
 826 }