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