source3/nmbd/nmbd_serverlistdb.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, write to the Free Software
  20    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  21
  22 */
  23
  24 #include "includes.h"
  25
  26 int updatecount = 0;
  27
  28 /*******************************************************************
  29   Remove all the servers in a work group.
  30   ******************************************************************/
  31
  32 void remove_all_servers(struct work_record *work)
  33 {
  34         struct server_record *servrec;
  35         struct server_record *nexts;
  36
  37         for (servrec = work->serverlist; servrec; servrec = nexts) {
  38                 DEBUG(7,("remove_all_servers: Removing server %s\n",servrec->serv.name));
  39                 nexts = servrec->next;
  40
  41                 if (servrec->prev)
  42                         servrec->prev->next = servrec->next;
  43                 if (servrec->next)
  44                         servrec->next->prev = servrec->prev;
  45
  46                 if (work->serverlist == servrec)
  47                         work->serverlist = servrec->next;
  48
  49                 ZERO_STRUCTP(servrec);
  50                 SAFE_FREE(servrec);
  51         }
  52
  53         work->subnet->work_changed = True;
  54 }
  55
  56 /***************************************************************************
  57   Add a server into the a workgroup serverlist.
  58   **************************************************************************/
  59
  60 static void add_server_to_workgroup(struct work_record *work,
  61                              struct server_record *servrec)
  62 {
  63         struct server_record *servrec2;
  64
  65         if (!work->serverlist) {
  66                 work->serverlist = servrec;
  67                 servrec->prev = NULL;
  68                 servrec->next = NULL;
  69                 return;
  70         }
  71
  72         for (servrec2 = work->serverlist; servrec2->next; servrec2 = servrec2->next)
  73                 ;
  74
  75         servrec2->next = servrec;
  76         servrec->next = NULL;
  77         servrec->prev = servrec2;
  78         work->subnet->work_changed = True;
  79 }
  80
  81 /****************************************************************************
  82   Find a server in a server list.
  83   **************************************************************************/
  84
  85 struct server_record *find_server_in_workgroup(struct work_record *work, const char *name)
  86 {
  87         struct server_record *ret;
  88
  89         for (ret = work->serverlist; ret; ret = ret->next) {
  90                 if (strequal(ret->serv.name,name))
  91                         return ret;
  92         }
  93         return NULL;
  94 }
  95
  96
  97 /****************************************************************************
  98   Remove a server entry from this workgroup.
  99   ****************************************************************************/
 100
 101 void remove_server_from_workgroup(struct work_record *work, struct server_record *servrec)
 102 {
 103         if (servrec->prev)
 104                 servrec->prev->next = servrec->next;
 105         if (servrec->next)
 106                 servrec->next->prev = servrec->prev;
 107
 108         if (work->serverlist == servrec)
 109                 work->serverlist = servrec->next;
 110
 111         ZERO_STRUCTP(servrec);
 112         SAFE_FREE(servrec);
 113         work->subnet->work_changed = True;
 114 }
 115
 116 /****************************************************************************
 117   Create a server entry on this workgroup.
 118   ****************************************************************************/
 119
 120 struct server_record *create_server_on_workgroup(struct work_record *work,
 121                                                  const char *name,int servertype,
 122                                                  int ttl, const char *comment)
 123 {
 124         struct server_record *servrec;
 125
 126         if (name[0] == '*') {
 127                 DEBUG(7,("create_server_on_workgroup: not adding name starting with '*' (%s)\n",
 128                         name));
 129                 return (NULL);
 130         }
 131
 132         if((servrec = find_server_in_workgroup(work, name)) != NULL) {
 133                 DEBUG(0,("create_server_on_workgroup: Server %s already exists on \
 134 workgroup %s. This is a bug.\n", name, work->work_group));
 135                 return NULL;
 136         }
 137
 138         if((servrec = SMB_MALLOC_P(struct server_record)) == NULL) {
 139                 DEBUG(0,("create_server_entry_on_workgroup: malloc fail !\n"));
 140                 return NULL;
 141         }
 142
 143         memset((char *)servrec,'\0',sizeof(*servrec));
 144
 145         servrec->subnet = work->subnet;
 146
 147         fstrcpy(servrec->serv.name,name);
 148         fstrcpy(servrec->serv.comment,comment);
 149         strupper_m(servrec->serv.name);
 150         servrec->serv.type  = servertype;
 151
 152         update_server_ttl(servrec, ttl);
 153
 154         add_server_to_workgroup(work, servrec);
 155
 156         DEBUG(3,("create_server_on_workgroup: Created server entry %s of type %x (%s) on \
 157 workgroup %s.\n", name,servertype,comment, work->work_group));
 158
 159         work->subnet->work_changed = True;
 160
 161         return(servrec);
 162 }
 163
 164 /*******************************************************************
 165  Update the ttl field of a server record.
 166 *******************************************************************/
 167
 168 void update_server_ttl(struct server_record *servrec, int ttl)
 169 {
 170         if(ttl > lp_max_ttl())
 171                 ttl = lp_max_ttl();
 172
 173         if(is_myname(servrec->serv.name))
 174                 servrec->death_time = PERMANENT_TTL;
 175         else
 176                 servrec->death_time = (ttl != PERMANENT_TTL) ? time(NULL)+(ttl*3) : PERMANENT_TTL;
 177
 178         servrec->subnet->work_changed = True;
 179 }
 180
 181 /*******************************************************************
 182   Expire old servers in the serverlist. A time of -1 indicates
 183   everybody dies except those with a death_time of PERMANENT_TTL (which is 0).
 184   This should only be called from expire_workgroups_and_servers().
 185   ******************************************************************/
 186
 187 void expire_servers(struct work_record *work, time_t t)
 188 {
 189         struct server_record *servrec;
 190         struct server_record *nexts;
 191
 192         for (servrec = work->serverlist; servrec; servrec = nexts) {
 193                 nexts = servrec->next;
 194
 195                 if ((servrec->death_time != PERMANENT_TTL) && ((t == -1) || (servrec->death_time < t))) {
 196                         DEBUG(3,("expire_old_servers: Removing timed out server %s\n",servrec->serv.name));
 197                         remove_server_from_workgroup(work, servrec);
 198                         work->subnet->work_changed = True;
 199                 }
 200         }
 201 }
 202
 203 /*******************************************************************
 204  Decide if we should write out a server record for this server.
 205  We return zero if we should not. Check if we've already written
 206  out this server record from an earlier subnet.
 207 ******************************************************************/
 208
 209 static uint32 write_this_server_name( struct subnet_record *subrec,
 210                                       struct work_record *work,
 211                                       struct server_record *servrec)
 212 {
 213         struct subnet_record *ssub;
 214         struct work_record *iwork;
 215
 216         /* Go through all the subnets we have already seen. */
 217         for (ssub = FIRST_SUBNET; ssub && (ssub != subrec); ssub = NEXT_SUBNET_INCLUDING_UNICAST(ssub)) {
 218                 for(iwork = ssub->workgrouplist; iwork; iwork = iwork->next) {
 219                         if(find_server_in_workgroup( iwork, servrec->serv.name) != NULL) {
 220                                 /*
 221                                  * We have already written out this server record, don't
 222                                  * do it again. This gives precedence to servers we have seen
 223                                  * on the broadcast subnets over servers that may have been
 224                                  * added via a sync on the unicast_subet.
 225                                  *
 226                                  * The correct way to do this is to have a serverlist file
 227                                  * per subnet - this means changes to smbd as well. I may
 228                                  * add this at a later date (JRA).
 229                                  */
 230
 231                                 return 0;
 232                         }
 233                 }
 234         }
 235
 236         return servrec->serv.type;
 237 }
 238
 239 /*******************************************************************
 240  Decide if we should write out a workgroup record for this workgroup.
 241  We return zero if we should not. Don't write out lp_workgroup() (we've
 242  already done it) and also don't write out a second workgroup record
 243  on the unicast subnet that we've already written out on one of the
 244  broadcast subnets.
 245 ******************************************************************/
 246
 247 static uint32 write_this_workgroup_name( struct subnet_record *subrec,
 248                                          struct work_record *work)
 249 {
 250         struct subnet_record *ssub;
 251
 252         if(strequal(lp_workgroup(), work->work_group))
 253                 return 0;
 254
 255         /* This is a workgroup we have seen on a broadcast subnet. All
 256                 these have the same type. */
 257
 258         if(subrec != unicast_subnet)
 259                 return (SV_TYPE_DOMAIN_ENUM|SV_TYPE_NT|SV_TYPE_LOCAL_LIST_ONLY);
 260
 261         for(ssub = FIRST_SUBNET; ssub;  ssub = NEXT_SUBNET_EXCLUDING_UNICAST(ssub)) {
 262                 /* This is the unicast subnet so check if we've already written out
 263                         this subnet when we passed over the broadcast subnets. */
 264
 265                 if(find_workgroup_on_subnet( ssub, work->work_group) != NULL)
 266                         return 0;
 267         }
 268
 269         /* All workgroups on the unicast subnet (except our own, which we
 270                 have already written out) cannot be local. */
 271
 272         return (SV_TYPE_DOMAIN_ENUM|SV_TYPE_NT);
 273 }
 274
 275 /*******************************************************************
 276   Write out the browse.dat file.
 277   ******************************************************************/
 278
 279 void write_browse_list_entry(XFILE *fp, const char *name, uint32 rec_type,
 280                 const char *local_master_browser_name, const char *description)
 281 {
 282         fstring tmp;
 283
 284         slprintf(tmp,sizeof(tmp)-1, "\"%s\"", name);
 285         x_fprintf(fp, "%-25s ", tmp);
 286         x_fprintf(fp, "%08x ", rec_type);
 287         slprintf(tmp, sizeof(tmp)-1, "\"%s\" ", local_master_browser_name);
 288         x_fprintf(fp, "%-30s", tmp);
 289         x_fprintf(fp, "\"%s\"\n", description);
 290 }
 291
 292 void write_browse_list(time_t t, BOOL force_write)
 293 {
 294         struct subnet_record *subrec;
 295         struct work_record *work;
 296         struct server_record *servrec;
 297         pstring fname,fnamenew;
 298         uint32 stype;
 299         int i;
 300         XFILE *fp;
 301         BOOL list_changed = force_write;
 302         static time_t lasttime = 0;
 303
 304         /* Always dump if we're being told to by a signal. */
 305         if(force_write == False) {
 306                 if (!lasttime)
 307                         lasttime = t;
 308                 if (t - lasttime < 5)
 309                         return;
 310         }
 311
 312         lasttime = t;
 313
 314         dump_workgroups(force_write);
 315
 316         for (subrec = FIRST_SUBNET; subrec ; subrec = NEXT_SUBNET_INCLUDING_UNICAST(subrec)) {
 317                 if(subrec->work_changed) {
 318                         list_changed = True;
 319                         break;
 320                 }
 321         }
 322
 323         if(!list_changed)
 324                 return;
 325
 326         updatecount++;
 327
 328         pstrcpy(fname,lp_lockdir());
 329         trim_char(fname,'\0' ,'/');
 330         pstrcat(fname,"/");
 331         pstrcat(fname,SERVER_LIST);
 332         pstrcpy(fnamenew,fname);
 333         pstrcat(fnamenew,".");
 334
 335         fp = x_fopen(fnamenew,O_WRONLY|O_CREAT|O_TRUNC, 0644);
 336
 337         if (!fp) {
 338                 DEBUG(0,("write_browse_list: Can't open file %s. Error was %s\n",
 339                         fnamenew,strerror(errno)));
 340                 return;
 341         }
 342
 343         /*
 344          * Write out a record for our workgroup. Use the record from the first
 345          * subnet.
 346          */
 347
 348         if((work = find_workgroup_on_subnet(FIRST_SUBNET, lp_workgroup())) == NULL) {
 349                 DEBUG(0,("write_browse_list: Fatal error - cannot find my workgroup %s\n",
 350                         lp_workgroup()));
 351                 x_fclose(fp);
 352                 return;
 353         }
 354
 355         write_browse_list_entry(fp, work->work_group,
 356                 SV_TYPE_DOMAIN_ENUM|SV_TYPE_NT|SV_TYPE_LOCAL_LIST_ONLY,
 357                 work->local_master_browser_name, work->work_group);
 358
 359         /*
 360          * We need to do something special for our own names.
 361          * This is due to the fact that we may be a local master browser on
 362          * one of our broadcast subnets, and a domain master on the unicast
 363          * subnet. We iterate over the subnets and only write out the name
 364          * once.
 365          */
 366
 367         for (i=0; my_netbios_names(i); i++) {
 368                 stype = 0;
 369                 for (subrec = FIRST_SUBNET; subrec ; subrec = NEXT_SUBNET_INCLUDING_UNICAST(subrec)) {
 370                         if((work = find_workgroup_on_subnet( subrec, lp_workgroup() )) == NULL)
 371                                 continue;
 372                         if((servrec = find_server_in_workgroup( work, my_netbios_names(i))) == NULL)
 373                                 continue;
 374
 375                         stype |= servrec->serv.type;
 376                 }
 377
 378                 /* Output server details, plus what workgroup they're in. */
 379                 write_browse_list_entry(fp, my_netbios_names(i), stype,
 380                         string_truncate(lp_serverstring(), MAX_SERVER_STRING_LENGTH), lp_workgroup());
 381         }
 382
 383         for (subrec = FIRST_SUBNET; subrec ; subrec = NEXT_SUBNET_INCLUDING_UNICAST(subrec)) {
 384                 subrec->work_changed = False;
 385
 386                 for (work = subrec->workgrouplist; work ; work = work->next) {
 387                         /* Write out a workgroup record for a workgroup. */
 388                         uint32 wg_type = write_this_workgroup_name( subrec, work);
 389
 390                         if(wg_type) {
 391                                 write_browse_list_entry(fp, work->work_group, wg_type,
 392                                                 work->local_master_browser_name,
 393                                                 work->work_group);
 394                         }
 395
 396                         /* Now write out any server records a workgroup may have. */
 397
 398                         for (servrec = work->serverlist; servrec ; servrec = servrec->next) {
 399                                 uint32 serv_type;
 400
 401                                 /* We have already written our names here. */
 402                                 if(is_myname(servrec->serv.name))
 403                                         continue;
 404
 405                                 serv_type = write_this_server_name(subrec, work, servrec);
 406                                 if(serv_type) {
 407                                         /* Output server details, plus what workgroup they're in. */
 408                                         write_browse_list_entry(fp, servrec->serv.name, serv_type,
 409                                                 servrec->serv.comment, work->work_group);
 410                                 }
 411                         }
 412                 }
 413         }
 414
 415         x_fclose(fp);
 416         unlink(fname);
 417         chmod(fnamenew,0644);
 418         rename(fnamenew,fname);
 419         DEBUG(3,("write_browse_list: Wrote browse list into file %s\n",fname));
 420 }