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