source/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 2 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program; if not, write to the Free Software
  20    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  21
  22 */
  23
  24 #include "includes.h"
  25
  26 extern int ClientNMB;
  27
  28 int updatecount = 0;
  29
  30 /*******************************************************************
  31   Remove all the servers in a work group.
  32   ******************************************************************/
  33
  34 void remove_all_servers(struct work_record *work)
  35 {
  36   struct server_record *servrec;
  37   struct server_record *nexts;
  38
  39   for (servrec = work->serverlist; servrec; servrec = nexts)
  40   {
  41     DEBUG(7,("remove_all_servers: Removing server %s\n",servrec->serv.name));
  42     nexts = servrec->next;
  43
  44     if (servrec->prev)
  45       servrec->prev->next = servrec->next;
  46     if (servrec->next)
  47       servrec->next->prev = servrec->prev;
  48
  49     if (work->serverlist == servrec)
  50       work->serverlist = servrec->next;
  51
  52     ZERO_STRUCTP(servrec);
  53     SAFE_FREE(servrec);
  54
  55   }
  56
  57   work->subnet->work_changed = True;
  58 }
  59
  60 /***************************************************************************
  61   Add a server into the a workgroup serverlist.
  62   **************************************************************************/
  63
  64 static void add_server_to_workgroup(struct work_record *work,
  65                              struct server_record *servrec)
  66 {
  67   struct server_record *servrec2;
  68
  69   if (!work->serverlist)
  70   {
  71     work->serverlist = servrec;
  72     servrec->prev = NULL;
  73     servrec->next = NULL;
  74     return;
  75   }
  76
  77   for (servrec2 = work->serverlist; servrec2->next; servrec2 = servrec2->next)
  78     ;
  79
  80   servrec2->next = servrec;
  81   servrec->next = NULL;
  82   servrec->prev = servrec2;
  83   work->subnet->work_changed = True;
  84 }
  85
  86 /****************************************************************************
  87   Find a server in a server list.
  88   **************************************************************************/
  89
  90 struct server_record *find_server_in_workgroup(struct work_record *work, const char *name)
  91 {
  92   struct server_record *ret;
  93
  94   for (ret = work->serverlist; ret; ret = ret->next)
  95   {
  96     if (strequal(ret->serv.name,name))
  97       return ret;
  98   }
  99   return NULL;
 100 }
 101
 102
 103 /****************************************************************************
 104   Remove a server entry from this workgroup.
 105   ****************************************************************************/
 106
 107 void remove_server_from_workgroup(struct work_record *work, struct server_record *servrec)
 108 {
 109   if (servrec->prev)
 110     servrec->prev->next = servrec->next;
 111   if (servrec->next)
 112     servrec->next->prev = servrec->prev;
 113
 114   if (work->serverlist == servrec)
 115     work->serverlist = servrec->next;
 116
 117   ZERO_STRUCTP(servrec);
 118   SAFE_FREE(servrec);
 119   work->subnet->work_changed = True;
 120 }
 121
 122 /****************************************************************************
 123   Create a server entry on this workgroup.
 124   ****************************************************************************/
 125
 126 struct server_record *create_server_on_workgroup(struct work_record *work,
 127                                                  const char *name,int servertype,
 128                                                  int ttl, const char *comment)
 129 {
 130   struct server_record *servrec;
 131
 132   if (name[0] == '*')
 133   {
 134       DEBUG(7,("create_server_on_workgroup: not adding name starting with '*' (%s)\n",
 135              name));
 136       return (NULL);
 137   }
 138
 139   if((servrec = find_server_in_workgroup(work, name)) != NULL)
 140   {
 141     DEBUG(0,("create_server_on_workgroup: Server %s already exists on \
 142 workgroup %s. This is a bug.\n", name, work->work_group));
 143     return NULL;
 144   }
 145
 146   if((servrec = (struct server_record *)malloc(sizeof(*servrec))) == NULL)
 147   {
 148     DEBUG(0,("create_server_entry_on_workgroup: malloc fail !\n"));
 149     return NULL;
 150   }
 151
 152   memset((char *)servrec,'\0',sizeof(*servrec));
 153
 154   servrec->subnet = work->subnet;
 155
 156   StrnCpy(servrec->serv.name,name,sizeof(servrec->serv.name)-1);
 157   StrnCpy(servrec->serv.comment,comment,sizeof(servrec->serv.comment)-1);
 158   strupper(servrec->serv.name);
 159   servrec->serv.type  = servertype;
 160
 161   update_server_ttl(servrec, ttl);
 162
 163   add_server_to_workgroup(work, servrec);
 164
 165   DEBUG(3,("create_server_on_workgroup: Created server entry %s of type %x (%s) on \
 166 workgroup %s.\n", name,servertype,comment, work->work_group));
 167
 168   work->subnet->work_changed = True;
 169
 170   return(servrec);
 171 }
 172
 173 /*******************************************************************
 174  Update the ttl field of a server record.
 175 *******************************************************************/
 176
 177 void update_server_ttl(struct server_record *servrec, int ttl)
 178 {
 179   if(ttl > lp_max_ttl())
 180     ttl = lp_max_ttl();
 181
 182   if(is_myname(servrec->serv.name))
 183     servrec->death_time = PERMANENT_TTL;
 184   else
 185     servrec->death_time = (ttl != PERMANENT_TTL) ? time(NULL)+(ttl*3) : PERMANENT_TTL;
 186
 187   servrec->subnet->work_changed = True;
 188 }
 189
 190 /*******************************************************************
 191   Expire old servers in the serverlist. A time of -1 indicates
 192   everybody dies except those with a death_time of PERMANENT_TTL (which is 0).
 193   This should only be called from expire_workgroups_and_servers().
 194   ******************************************************************/
 195
 196 void expire_servers(struct work_record *work, time_t t)
 197 {
 198   struct server_record *servrec;
 199   struct server_record *nexts;
 200
 201   for (servrec = work->serverlist; servrec; servrec = nexts)
 202   {
 203     nexts = servrec->next;
 204
 205     if ((servrec->death_time != PERMANENT_TTL) && ((t == -1) || (servrec->death_time < t)))
 206     {
 207       DEBUG(3,("expire_old_servers: Removing timed out server %s\n",servrec->serv.name));
 208       remove_server_from_workgroup(work, servrec);
 209       work->subnet->work_changed = True;
 210     }
 211   }
 212 }
 213
 214 /*******************************************************************
 215  Decide if we should write out a server record for this server.
 216  We return zero if we should not. Check if we've already written
 217  out this server record from an earlier subnet.
 218 ******************************************************************/
 219
 220 static uint32 write_this_server_name( struct subnet_record *subrec,
 221                                       struct work_record *work,
 222                                       struct server_record *servrec)
 223 {
 224   struct subnet_record *ssub;
 225   struct work_record *iwork;
 226
 227   /* Go through all the subnets we have already seen. */
 228   for (ssub = FIRST_SUBNET; ssub != subrec; ssub = NEXT_SUBNET_INCLUDING_UNICAST(ssub))
 229   {
 230     for(iwork = ssub->workgrouplist; iwork; iwork = iwork->next)
 231     {
 232       if(find_server_in_workgroup( iwork, servrec->serv.name) != NULL)
 233       {
 234         /*
 235          * We have already written out this server record, don't
 236          * do it again. This gives precedence to servers we have seen
 237          * on the broadcast subnets over servers that may have been
 238          * added via a sync on the unicast_subet.
 239          *
 240          * The correct way to do this is to have a serverlist file
 241          * per subnet - this means changes to smbd as well. I may
 242          * add this at a later date (JRA).
 243          */
 244
 245         return 0;
 246       }
 247     }
 248   }
 249
 250   return servrec->serv.type;
 251 }
 252
 253 /*******************************************************************
 254  Decide if we should write out a workgroup record for this workgroup.
 255  We return zero if we should not. Don't write out lp_workgroup() (we've
 256  already done it) and also don't write out a second workgroup record
 257  on the unicast subnet that we've already written out on one of the
 258  broadcast subnets.
 259 ******************************************************************/
 260
 261 static uint32 write_this_workgroup_name( struct subnet_record *subrec,
 262                                          struct work_record *work)
 263 {
 264   struct subnet_record *ssub;
 265
 266   if(strequal(lp_workgroup(), work->work_group))
 267     return 0;
 268
 269   /* This is a workgroup we have seen on a broadcast subnet. All
 270      these have the same type. */
 271
 272   if(subrec != unicast_subnet)
 273     return (SV_TYPE_DOMAIN_ENUM|SV_TYPE_NT|SV_TYPE_LOCAL_LIST_ONLY);
 274
 275   for(ssub = FIRST_SUBNET; ssub;  ssub = NEXT_SUBNET_EXCLUDING_UNICAST(ssub))
 276   {
 277     /* This is the unicast subnet so check if we've already written out
 278        this subnet when we passed over the broadcast subnets. */
 279
 280     if(find_workgroup_on_subnet( ssub, work->work_group) != NULL)
 281       return 0;
 282   }
 283
 284   /* All workgroups on the unicast subnet (except our own, which we
 285      have already written out) cannot be local. */
 286
 287   return (SV_TYPE_DOMAIN_ENUM|SV_TYPE_NT);
 288 }
 289
 290 /*******************************************************************
 291   Write out the browse.dat file.
 292   ******************************************************************/
 293
 294 void write_browse_list_entry(XFILE *fp, const char *name, uint32 rec_type,
 295                 const char *local_master_browser_name, const char *description)
 296 {
 297         fstring tmp;
 298
 299         slprintf(tmp,sizeof(tmp)-1, "\"%s\"", name);
 300         x_fprintf(fp, "%-25s ", tmp);
 301         x_fprintf(fp, "%08x ", rec_type);
 302         slprintf(tmp, sizeof(tmp)-1, "\"%s\" ", local_master_browser_name);
 303         x_fprintf(fp, "%-30s", tmp);
 304         x_fprintf(fp, "\"%s\"\n", description);
 305 }
 306
 307 void write_browse_list(time_t t, BOOL force_write)
 308 {
 309   struct subnet_record *subrec;
 310   struct work_record *work;
 311   struct server_record *servrec;
 312   pstring fname,fnamenew;
 313   uint32 stype;
 314   int i;
 315   XFILE *fp;
 316   BOOL list_changed = force_write;
 317   static time_t lasttime = 0;
 318
 319   /* Always dump if we're being told to by a signal. */
 320   if(force_write == False)
 321   {
 322     if (!lasttime)
 323       lasttime = t;
 324     if (t - lasttime < 5)
 325       return;
 326   }
 327
 328   lasttime = t;
 329
 330   dump_workgroups(force_write);
 331
 332   for (subrec = FIRST_SUBNET; subrec ; subrec = NEXT_SUBNET_INCLUDING_UNICAST(subrec))
 333   {
 334     if(subrec->work_changed)
 335     {
 336       list_changed = True;
 337       break;
 338     }
 339   }
 340
 341   if(!list_changed)
 342     return;
 343
 344   updatecount++;
 345
 346   pstrcpy(fname,lp_lockdir());
 347   trim_string(fname,NULL,"/");
 348   pstrcat(fname,"/");
 349   pstrcat(fname,SERVER_LIST);
 350   pstrcpy(fnamenew,fname);
 351   pstrcat(fnamenew,".");
 352
 353   fp = x_fopen(fnamenew,O_WRONLY|O_CREAT|O_TRUNC, 0644);
 354
 355   if (!fp)
 356   {
 357     DEBUG(0,("write_browse_list: Can't open file %s. Error was %s\n",
 358               fnamenew,strerror(errno)));
 359     return;
 360   }
 361
 362   /*
 363    * Write out a record for our workgroup. Use the record from the first
 364    * subnet.
 365    */
 366
 367   if((work = find_workgroup_on_subnet(FIRST_SUBNET, lp_workgroup())) == NULL)
 368   {
 369     DEBUG(0,("write_browse_list: Fatal error - cannot find my workgroup %s\n",
 370              lp_workgroup()));
 371     x_fclose(fp);
 372     return;
 373   }
 374
 375   write_browse_list_entry(fp, work->work_group,
 376      SV_TYPE_DOMAIN_ENUM|SV_TYPE_NT|SV_TYPE_LOCAL_LIST_ONLY,
 377      work->local_master_browser_name, work->work_group);
 378
 379   /*
 380    * We need to do something special for our own names.
 381    * This is due to the fact that we may be a local master browser on
 382    * one of our broadcast subnets, and a domain master on the unicast
 383    * subnet. We iterate over the subnets and only write out the name
 384    * once.
 385    */
 386
 387   for (i=0; my_netbios_names(i); i++)
 388   {
 389     stype = 0;
 390     for (subrec = FIRST_SUBNET; subrec ; subrec = NEXT_SUBNET_INCLUDING_UNICAST(subrec))
 391     {
 392       if((work = find_workgroup_on_subnet( subrec, lp_workgroup() )) == NULL)
 393         continue;
 394       if((servrec = find_server_in_workgroup( work, my_netbios_names(i))) == NULL)
 395         continue;
 396
 397       stype |= servrec->serv.type;
 398     }
 399
 400     /* Output server details, plus what workgroup they're in. */
 401     write_browse_list_entry(fp, my_netbios_names(i), stype,
 402         string_truncate(lp_serverstring(), MAX_SERVER_STRING_LENGTH), lp_workgroup());
 403   }
 404
 405   for (subrec = FIRST_SUBNET; subrec ; subrec = NEXT_SUBNET_INCLUDING_UNICAST(subrec))
 406   {
 407     subrec->work_changed = False;
 408
 409     for (work = subrec->workgrouplist; work ; work = work->next)
 410     {
 411       /* Write out a workgroup record for a workgroup. */
 412       uint32 wg_type = write_this_workgroup_name( subrec, work);
 413
 414       if(wg_type)
 415       {
 416         write_browse_list_entry(fp, work->work_group, wg_type,
 417                                 work->local_master_browser_name,
 418                                 work->work_group);
 419       }
 420
 421       /* Now write out any server records a workgroup may have. */
 422
 423       for (servrec = work->serverlist; servrec ; servrec = servrec->next)
 424       {
 425         uint32 serv_type;
 426
 427         /* We have already written our names here. */
 428         if(is_myname(servrec->serv.name))
 429           continue;
 430
 431         serv_type = write_this_server_name(subrec, work, servrec);
 432
 433         if(serv_type)
 434         {
 435           /* Output server details, plus what workgroup they're in. */
 436           write_browse_list_entry(fp, servrec->serv.name, serv_type,
 437                                  servrec->serv.comment, work->work_group);
 438         }
 439       }
 440     }
 441   }
 442
 443   x_fclose(fp);
 444   unlink(fname);
 445   chmod(fnamenew,0644);
 446   rename(fnamenew,fname);
 447   DEBUG(3,("write_browse_list: Wrote browse list into file %s\n",fname));
 448 }