source/nmbd/nmbd_serverlistdb.c

   1 /*
   2    Unix SMB/Netbios implementation.
   3    Version 1.9.
   4    NBT netbios routines and daemon - version 2
   5    Copyright (C) Andrew Tridgell 1994-1998
   6    Copyright (C) Luke Kenneth Casson Leighton 1994-1998
   7    Copyright (C) Jeremy Allison 1994-1998
   8
   9    This program is free software; you can redistribute it and/or modify
  10    it under the terms of the GNU General Public License as published by
  11    the Free Software Foundation; either version 2 of the License, or
  12    (at your option) any later version.
  13
  14    This program is distributed in the hope that it will be useful,
  15    but WITHOUT ANY WARRANTY; without even the implied warranty of
  16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17    GNU General Public License for more details.
  18
  19    You should have received a copy of the GNU General Public License
  20    along with this program; if not, write to the Free Software
  21    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  22
  23 */
  24
  25 #include "includes.h"
  26 #include "smb.h"
  27
  28 extern int ClientNMB;
  29
  30 extern int DEBUGLEVEL;
  31
  32 extern fstring global_myworkgroup;
  33 extern char **my_netbios_names;
  34
  35 int updatecount = 0;
  36
  37 /*******************************************************************
  38   Remove all the servers in a work group.
  39   ******************************************************************/
  40
  41 void remove_all_servers(struct work_record *work)
  42 {
  43   struct server_record *servrec;
  44   struct server_record *nexts;
  45
  46   for (servrec = work->serverlist; servrec; servrec = nexts)
  47   {
  48     DEBUG(7,("remove_all_servers: Removing server %s\n",servrec->serv.name));
  49     nexts = servrec->next;
  50
  51     if (servrec->prev)
  52       servrec->prev->next = servrec->next;
  53     if (servrec->next)
  54       servrec->next->prev = servrec->prev;
  55
  56     if (work->serverlist == servrec)
  57       work->serverlist = servrec->next;
  58
  59     ZERO_STRUCTP(servrec);
  60     free((char *)servrec);
  61
  62   }
  63
  64   work->subnet->work_changed = True;
  65 }
  66
  67 /***************************************************************************
  68   Add a server into the a workgroup serverlist.
  69   **************************************************************************/
  70
  71 static void add_server_to_workgroup(struct work_record *work,
  72                              struct server_record *servrec)
  73 {
  74   struct server_record *servrec2;
  75
  76   if (!work->serverlist)
  77   {
  78     work->serverlist = servrec;
  79     servrec->prev = NULL;
  80     servrec->next = NULL;
  81     return;
  82   }
  83
  84   for (servrec2 = work->serverlist; servrec2->next; servrec2 = servrec2->next)
  85     ;
  86
  87   servrec2->next = servrec;
  88   servrec->next = NULL;
  89   servrec->prev = servrec2;
  90   work->subnet->work_changed = True;
  91 }
  92
  93 /****************************************************************************
  94   Find a server in a server list.
  95   **************************************************************************/
  96
  97 struct server_record *find_server_in_workgroup(struct work_record *work, char *name)
  98 {
  99   struct server_record *ret;
 100
 101   for (ret = work->serverlist; ret; ret = ret->next)
 102   {
 103     if (strequal(ret->serv.name,name))
 104       return ret;
 105   }
 106   return NULL;
 107 }
 108
 109
 110 /****************************************************************************
 111   Remove a server entry from this workgroup.
 112   ****************************************************************************/
 113
 114 void remove_server_from_workgroup(struct work_record *work, struct server_record *servrec)
 115 {
 116   if (servrec->prev)
 117     servrec->prev->next = servrec->next;
 118   if (servrec->next)
 119     servrec->next->prev = servrec->prev;
 120
 121   if (work->serverlist == servrec)
 122     work->serverlist = servrec->next;
 123
 124   ZERO_STRUCTP(servrec);
 125   free((char *)servrec);
 126   work->subnet->work_changed = True;
 127 }
 128
 129 /****************************************************************************
 130   Create a server entry on this workgroup.
 131   ****************************************************************************/
 132
 133 struct server_record *create_server_on_workgroup(struct work_record *work,
 134                                                  char *name,int servertype,
 135                                                  int ttl,char *comment)
 136 {
 137   struct server_record *servrec;
 138
 139   if (name[0] == '*')
 140   {
 141       DEBUG(7,("create_server_on_workgroup: not adding name starting with '*' (%s)\n",
 142              name));
 143       return (NULL);
 144   }
 145
 146   if((servrec = find_server_in_workgroup(work, name)) != NULL)
 147   {
 148     DEBUG(0,("create_server_on_workgroup: Server %s already exists on \
 149 workgroup %s. This is a bug.\n", name, work->work_group));
 150     return NULL;
 151   }
 152
 153   if((servrec = (struct server_record *)malloc(sizeof(*servrec))) == NULL)
 154   {
 155     DEBUG(0,("create_server_entry_on_workgroup: malloc fail !\n"));
 156     return NULL;
 157   }
 158
 159   memset((char *)servrec,'\0',sizeof(*servrec));
 160
 161   servrec->subnet = work->subnet;
 162
 163   StrnCpy(servrec->serv.name,name,sizeof(servrec->serv.name)-1);
 164   StrnCpy(servrec->serv.comment,comment,sizeof(servrec->serv.comment)-1);
 165   strupper(servrec->serv.name);
 166   servrec->serv.type  = servertype;
 167
 168   update_server_ttl(servrec, ttl);
 169
 170   add_server_to_workgroup(work, servrec);
 171
 172   DEBUG(3,("create_server_on_workgroup: Created server entry %s of type %x (%s) on \
 173 workgroup %s.\n", name,servertype,comment, work->work_group));
 174
 175   work->subnet->work_changed = True;
 176
 177   return(servrec);
 178 }
 179
 180 /*******************************************************************
 181  Update the ttl field of a server record.
 182 *******************************************************************/
 183
 184 void update_server_ttl(struct server_record *servrec, int ttl)
 185 {
 186   if(ttl > lp_max_ttl())
 187     ttl = lp_max_ttl();
 188
 189   if(is_myname(servrec->serv.name))
 190     servrec->death_time = PERMANENT_TTL;
 191   else
 192     servrec->death_time = (ttl != PERMANENT_TTL) ? time(NULL)+(ttl*3) : PERMANENT_TTL;
 193
 194   servrec->subnet->work_changed = True;
 195 }
 196
 197 /*******************************************************************
 198   Expire old servers in the serverlist. A time of -1 indicates
 199   everybody dies except those with a death_time of PERMANENT_TTL (which is 0).
 200   This should only be called from expire_workgroups_and_servers().
 201   ******************************************************************/
 202
 203 void expire_servers(struct work_record *work, time_t t)
 204 {
 205   struct server_record *servrec;
 206   struct server_record *nexts;
 207
 208   for (servrec = work->serverlist; servrec; servrec = nexts)
 209   {
 210     nexts = servrec->next;
 211
 212     if ((servrec->death_time != PERMANENT_TTL) && ((t == -1) || (servrec->death_time < t)))
 213     {
 214       DEBUG(3,("expire_old_servers: Removing timed out server %s\n",servrec->serv.name));
 215       remove_server_from_workgroup(work, servrec);
 216       work->subnet->work_changed = True;
 217     }
 218   }
 219 }
 220
 221 /*******************************************************************
 222  Decide if we should write out a server record for this server.
 223  We return zero if we should not. Check if we've already written
 224  out this server record from an earlier subnet.
 225 ******************************************************************/
 226
 227 static uint32 write_this_server_name( struct subnet_record *subrec,
 228                                       struct work_record *work,
 229                                       struct server_record *servrec)
 230 {
 231   struct subnet_record *ssub;
 232   struct work_record *iwork;
 233
 234   /* Go through all the subnets we have already seen. */
 235   for (ssub = FIRST_SUBNET; ssub != subrec; ssub = NEXT_SUBNET_INCLUDING_UNICAST(ssub))
 236   {
 237     for(iwork = ssub->workgrouplist; iwork; iwork = iwork->next)
 238     {
 239       if(find_server_in_workgroup( iwork, servrec->serv.name) != NULL)
 240       {
 241         /*
 242          * We have already written out this server record, don't
 243          * do it again. This gives precedence to servers we have seen
 244          * on the broadcast subnets over servers that may have been
 245          * added via a sync on the unicast_subet.
 246          *
 247          * The correct way to do this is to have a serverlist file
 248          * per subnet - this means changes to smbd as well. I may
 249          * add this at a later date (JRA).
 250          */
 251
 252         return 0;
 253       }
 254     }
 255   }
 256
 257   return servrec->serv.type;
 258 }
 259
 260 /*******************************************************************
 261  Decide if we should write out a workgroup record for this workgroup.
 262  We return zero if we should not. Don't write out global_myworkgroup (we've
 263  already done it) and also don't write out a second workgroup record
 264  on the unicast subnet that we've already written out on one of the
 265  broadcast subnets.
 266 ******************************************************************/
 267
 268 static uint32 write_this_workgroup_name( struct subnet_record *subrec,
 269                                          struct work_record *work)
 270 {
 271   struct subnet_record *ssub;
 272
 273   if(strequal(global_myworkgroup, work->work_group))
 274     return 0;
 275
 276   /* This is a workgroup we have seen on a broadcast subnet. All
 277      these have the same type. */
 278
 279   if(subrec != unicast_subnet)
 280     return (SV_TYPE_DOMAIN_ENUM|SV_TYPE_NT|SV_TYPE_LOCAL_LIST_ONLY);
 281
 282   for(ssub = FIRST_SUBNET; ssub;  ssub = NEXT_SUBNET_EXCLUDING_UNICAST(ssub))
 283   {
 284     /* This is the unicast subnet so check if we've already written out
 285        this subnet when we passed over the broadcast subnets. */
 286
 287     if(find_workgroup_on_subnet( ssub, work->work_group) != NULL)
 288       return 0;
 289   }
 290
 291   /* All workgroups on the unicast subnet (except our own, which we
 292      have already written out) cannot be local. */
 293
 294   return (SV_TYPE_DOMAIN_ENUM|SV_TYPE_NT);
 295 }
 296
 297 /*******************************************************************
 298   Write out the browse.dat file.
 299   ******************************************************************/
 300
 301 void write_browse_list(time_t t, BOOL force_write)
 302 {
 303   struct subnet_record *subrec;
 304   struct work_record *work;
 305   struct server_record *servrec;
 306   pstring fname,fnamenew;
 307   uint32 stype;
 308   fstring tmp;
 309   int i;
 310   FILE *fp;
 311   BOOL list_changed = force_write;
 312   static time_t lasttime = 0;
 313
 314   /* Always dump if we're being told to by a signal. */
 315   if(force_write == False)
 316   {
 317     if (!lasttime)
 318       lasttime = t;
 319     if (t - lasttime < 5)
 320       return;
 321   }
 322
 323   lasttime = t;
 324
 325   dump_workgroups(force_write);
 326
 327   for (subrec = FIRST_SUBNET; subrec ; subrec = NEXT_SUBNET_INCLUDING_UNICAST(subrec))
 328   {
 329     if(subrec->work_changed)
 330     {
 331       list_changed = True;
 332       break;
 333     }
 334   }
 335
 336   if(!list_changed)
 337     return;
 338
 339   updatecount++;
 340
 341   pstrcpy(fname,lp_lockdir());
 342   trim_string(fname,NULL,"/");
 343   pstrcat(fname,"/");
 344   pstrcat(fname,SERVER_LIST);
 345   pstrcpy(fnamenew,fname);
 346   pstrcat(fnamenew,".");
 347
 348   fp = sys_fopen(fnamenew,"w");
 349
 350   if (!fp)
 351   {
 352     DEBUG(0,("write_browse_list: Can't open file %s. Error was %s\n",
 353               fnamenew,strerror(errno)));
 354     return;
 355   }
 356
 357   /*
 358    * Write out a record for our workgroup. Use the record from the first
 359    * subnet.
 360    */
 361
 362   if((work = find_workgroup_on_subnet(FIRST_SUBNET, global_myworkgroup)) == NULL)
 363   {
 364     DEBUG(0,("write_browse_list: Fatal error - cannot find my workgroup %s\n",
 365              global_myworkgroup));
 366     fclose(fp);
 367     return;
 368   }
 369
 370   slprintf(tmp,sizeof(tmp)-1, "\"%s\"", work->work_group);
 371   fprintf(fp, "%-25s ", tmp);
 372   fprintf(fp, "%08x ", SV_TYPE_DOMAIN_ENUM|SV_TYPE_NT|SV_TYPE_LOCAL_LIST_ONLY);
 373   slprintf(tmp, sizeof(tmp)-1, "\"%s\" ", work->local_master_browser_name);
 374   fprintf(fp, "%-30s", tmp);
 375   fprintf(fp, "\"%s\"\n", work->work_group);
 376
 377   /*
 378    * We need to do something special for our own names.
 379    * This is due to the fact that we may be a local master browser on
 380    * one of our broadcast subnets, and a domain master on the unicast
 381    * subnet. We iterate over the subnets and only write out the name
 382    * once.
 383    */
 384
 385   for (i=0; my_netbios_names[i]; i++)
 386   {
 387     stype = 0;
 388     for (subrec = FIRST_SUBNET; subrec ; subrec = NEXT_SUBNET_INCLUDING_UNICAST(subrec))
 389     {
 390       if((work = find_workgroup_on_subnet( subrec, global_myworkgroup )) == NULL)
 391         continue;
 392       if((servrec = find_server_in_workgroup( work, my_netbios_names[i])) == NULL)
 393         continue;
 394
 395       stype |= servrec->serv.type;
 396     }
 397
 398     /* Output server details, plus what workgroup they're in. */
 399     slprintf(tmp, sizeof(tmp)-1, "\"%s\"", my_netbios_names[i]);
 400     fprintf(fp, "%-25s ", tmp);
 401     fprintf(fp, "%08x ", stype);
 402     slprintf(tmp, sizeof(tmp)-1, "\"%s\" ",
 403              string_truncate(lp_serverstring(), MAX_SERVER_STRING_LENGTH));
 404     fprintf(fp, "%-30s", tmp);
 405     fprintf(fp, "\"%s\"\n", global_myworkgroup);
 406   }
 407
 408   for (subrec = FIRST_SUBNET; subrec ; subrec = NEXT_SUBNET_INCLUDING_UNICAST(subrec))
 409   {
 410     subrec->work_changed = False;
 411
 412     for (work = subrec->workgrouplist; work ; work = work->next)
 413     {
 414       /* Write out a workgroup record for a workgroup. */
 415       uint32 wg_type = write_this_workgroup_name( subrec, work);
 416
 417       if(wg_type)
 418       {
 419         slprintf(tmp, sizeof(tmp)-1, "\"%s\"", work->work_group);
 420         fprintf(fp, "%-25s ", tmp);
 421
 422         fprintf(fp, "%08x ", wg_type);
 423         slprintf(tmp, sizeof(tmp)-1, "\"%s\" ", work->local_master_browser_name);
 424         fprintf(fp, "%-30s", tmp);
 425         fprintf(fp, "\"%s\"\n", work->work_group);
 426       }
 427
 428       /* Now write out any server records a workgroup may have. */
 429
 430       for (servrec = work->serverlist; servrec ; servrec = servrec->next)
 431       {
 432         uint32 serv_type;
 433
 434         /* We have already written our names here. */
 435         if(is_myname(servrec->serv.name))
 436           continue;
 437
 438         serv_type = write_this_server_name(subrec, work, servrec);
 439
 440         if(serv_type)
 441         {
 442           /* Output server details, plus what workgroup they're in. */
 443           slprintf(tmp, sizeof(tmp)-1, "\"%s\"", servrec->serv.name);
 444           fprintf(fp, "%-25s ", tmp);
 445           fprintf(fp, "%08x ", serv_type);
 446           slprintf(tmp, sizeof(tmp)-1, "\"%s\" ", servrec->serv.comment);
 447           fprintf(fp, "%-30s", tmp);
 448           fprintf(fp, "\"%s\"\n", work->work_group);
 449         }
 450       }
 451     }
 452   }
 453
 454   fclose(fp);
 455   unlink(fname);
 456   chmod(fnamenew,0644);
 457   rename(fnamenew,fname);
 458   DEBUG(3,("write_browse_list: Wrote browse list into file %s\n",fname));
 459 }