source/namedbname.c

   1 /*
   2    Unix SMB/Netbios implementation.
   3    Version 1.9.
   4    NBT netbios routines and daemon - version 2
   5    Copyright (C) Andrew Tridgell 1994-1997
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 2 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program; if not, write to the Free Software
  19    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  20
  21    Module name: namedbname.c
  22
  23    Revision History:
  24
  25    14 jan 96: lkcl@pires.co.uk
  26    added multiple workgroup domain master support
  27
  28    04 jul 96: lkcl@pires.co.uk
  29    created module namedbname containing name database functions
  30 */
  31
  32 #include "includes.h"
  33
  34 extern int DEBUGLEVEL;
  35
  36 extern pstring scope;
  37 extern struct in_addr ipzero;
  38 extern struct in_addr wins_ip;
  39 extern BOOL updatedlists;
  40
  41 extern struct subnet_record *subnetlist;
  42
  43 #define WINS_LIST "wins.dat"
  44
  45 uint16 nb_type = 0; /* samba's NetBIOS name type */
  46
  47
  48 /****************************************************************************
  49   samba's NetBIOS name type
  50
  51   XXXX maybe functionality could be set: B, M, P or H name registration
  52   and resolution could be set through nb_type. just a thought.
  53   ****************************************************************************/
  54 void set_samba_nb_type(void)
  55 {
  56   if (lp_wins_support() || (*lp_wins_server()))
  57   {
  58     nb_type = NB_MFLAG; /* samba is a 'hybrid' node type */
  59   }
  60   else
  61   {
  62     nb_type = NB_BFLAG; /* samba is broadcast-only node type */
  63   }
  64 }
  65
  66
  67 /****************************************************************************
  68   true if two netbios names are equal
  69 ****************************************************************************/
  70 BOOL name_equal(struct nmb_name *n1,struct nmb_name *n2)
  71 {
  72   return n1->name_type == n2->name_type &&
  73                  strequal(n1->name ,n2->name ) &&
  74          strequal(n1->scope,n2->scope);
  75 }
  76
  77
  78 /****************************************************************************
  79   true if the netbios name is ^1^2__MSBROWSE__^2^1
  80
  81   note: this name is registered if as a master browser or backup browser
  82   you are responsible for a workgroup (when you announce a domain by
  83   broadcasting on your local subnet, you announce it as coming from this
  84   name: see announce_host()).
  85
  86   **************************************************************************/
  87 BOOL ms_browser_name(char *name, int type)
  88 {
  89   return strequal(name,MSBROWSE) && type == 0x01;
  90 }
  91
  92
  93 /****************************************************************************
  94   add a netbios name into the namelist
  95   **************************************************************************/
  96 static void add_name(struct subnet_record *d, struct name_record *n)
  97 {
  98   struct name_record *n2;
  99
 100   if (!d) return;
 101
 102   if (!d->namelist)
 103   {
 104     d->namelist = n;
 105     n->prev = NULL;
 106     n->next = NULL;
 107     return;
 108   }
 109
 110   for (n2 = d->namelist; n2->next; n2 = n2->next) ;
 111
 112   n2->next = n;
 113   n->next = NULL;
 114   n->prev = n2;
 115
 116   if((d == wins_client_subnet) && lp_wins_support())
 117     updatedlists = True;
 118 }
 119
 120
 121 /****************************************************************************
 122   remove a name from the namelist. The pointer must be an element just
 123   retrieved
 124   **************************************************************************/
 125 void remove_name(struct subnet_record *d, struct name_record *n)
 126 {
 127   struct name_record *nlist;
 128   if (!d) return;
 129
 130   nlist = d->namelist;
 131
 132   while (nlist && nlist != n) nlist = nlist->next;
 133
 134   if (nlist)
 135   {
 136     if (nlist->next) nlist->next->prev = nlist->prev;
 137     if (nlist->prev) nlist->prev->next = nlist->next;
 138
 139     if(nlist == d->namelist)
 140       d->namelist = nlist->next;
 141
 142     if(nlist->ip_flgs != NULL)
 143       free(nlist->ip_flgs);
 144     free(nlist);
 145   }
 146
 147   if((d == wins_client_subnet) && lp_wins_support())
 148     updatedlists = True;
 149 }
 150
 151
 152 /****************************************************************************
 153   find a name in a subnet.
 154   **************************************************************************/
 155 struct name_record *find_name_on_subnet(struct subnet_record *d,
 156                         struct nmb_name *name, BOOL self_only)
 157 {
 158   struct name_record *n = d->namelist;
 159   struct name_record *ret;
 160
 161   for (ret = n; ret; ret = ret->next)
 162   {
 163     if (name_equal(&ret->name,name))
 164     {
 165       /* self search: self names only */
 166       if (self_only && (ret->source != SELF))
 167       {
 168         continue;
 169       }
 170       DEBUG(9,("find_name_on_subnet: on subnet %s - found name %s(%02x) source=%d\n",
 171                 inet_ntoa(d->bcast_ip), name->name, name->name_type, ret->source));
 172       return ret;
 173     }
 174   }
 175   DEBUG(9,("find_name_on_subnet: on subnet %s - name %s(%02x) NOT FOUND\n",
 176             inet_ntoa(d->bcast_ip), name->name, name->name_type));
 177   return NULL;
 178 }
 179
 180 /****************************************************************************
 181   dump a copy of the name table
 182   **************************************************************************/
 183 void dump_names(void)
 184 {
 185   struct name_record *n;
 186   fstring fname, fnamenew;
 187   time_t t = time(NULL);
 188
 189   FILE *f;
 190
 191   if(lp_wins_support() == False || wins_client_subnet == NULL)
 192     return;
 193
 194   fstrcpy(fname,lp_lockdir());
 195   trim_string(fname,NULL,"/");
 196   strcat(fname,"/");
 197   strcat(fname,WINS_LIST);
 198   fstrcpy(fnamenew,fname);
 199   strcat(fnamenew,".");
 200
 201   f = fopen(fnamenew,"w");
 202
 203   if (!f)
 204   {
 205     DEBUG(3,("Can't open %s - %s\n",fnamenew,strerror(errno)));
 206     return;
 207   }
 208
 209   DEBUG(4,("Dump of WINS name table:\n"));
 210
 211   for (n = wins_client_subnet->namelist; n; n = n->next)
 212    {
 213      int i;
 214
 215      DEBUG(4,("%15s ", inet_ntoa(wins_client_subnet->bcast_ip)));
 216      DEBUG(4,("%15s ", inet_ntoa(wins_client_subnet->mask_ip)));
 217      DEBUG(4,("%-19s TTL=%ld ",
 218                namestr(&n->name),
 219                n->death_time?n->death_time-t:0));
 220
 221      for (i = 0; i < n->num_ips; i++)
 222       {
 223         DEBUG(4,("%15s NB=%2x source=%d",
 224                  inet_ntoa(n->ip_flgs[i].ip),
 225                     n->ip_flgs[i].nb_flags,n->source));
 226
 227       }
 228      DEBUG(4,("\n"));
 229
 230      if (f && ((n->source == REGISTER) || (n->source == SELF)))
 231       {
 232       /* XXXX i have little imagination as to how to output nb_flags as
 233          anything other than as a hexadecimal number :-) */
 234
 235         fprintf(f, "%s#%02x %ld ",
 236                n->name.name,n->name.name_type, /* XXXX ignore scope for now */
 237                n->death_time);
 238
 239         for (i = 0; i < n->num_ips; i++)
 240         {
 241            fprintf(f, "%s %2x%c ",
 242                 inet_ntoa(n->ip_flgs[i].ip),
 243                 n->ip_flgs[i].nb_flags, (n->source == REGISTER ? 'R' : 'S'));
 244         }
 245         fprintf(f, "\n");
 246       }
 247
 248   }
 249
 250   fclose(f);
 251   unlink(fname);
 252   chmod(fnamenew,0644);
 253   rename(fnamenew,fname);
 254
 255   DEBUG(3,("Wrote wins database %s\n",fname));
 256 }
 257
 258
 259 /****************************************************************************
 260   load a netbios name database file
 261
 262   XXXX we cannot cope with loading Internet Group names, yet
 263   ****************************************************************************/
 264 void load_netbios_names(void)
 265 {
 266   struct subnet_record *d = wins_client_subnet;
 267   fstring fname;
 268
 269   FILE *f;
 270   pstring line;
 271
 272   if (!d) return;
 273
 274   fstrcpy(fname,lp_lockdir());
 275   trim_string(fname,NULL,"/");
 276   strcat(fname,"/");
 277   strcat(fname,WINS_LIST);
 278
 279   f = fopen(fname,"r");
 280
 281   if (!f) {
 282     DEBUG(2,("Can't open wins database file %s\n",fname));
 283     return;
 284   }
 285
 286   while (!feof(f))
 287     {
 288       pstring name_str, ip_str, ttd_str, nb_flags_str;
 289
 290       pstring name;
 291       int type = 0;
 292       unsigned int nb_flags;
 293       time_t ttd;
 294           struct in_addr ipaddr;
 295
 296           enum name_source source;
 297
 298       char *ptr;
 299           int count = 0;
 300
 301       char *p;
 302
 303       if (!fgets_slash(line,sizeof(pstring),f)) continue;
 304
 305       if (*line == '#') continue;
 306
 307         ptr = line;
 308
 309         if (next_token(&ptr,name_str    ,NULL)) ++count;
 310         if (next_token(&ptr,ttd_str     ,NULL)) ++count;
 311         if (next_token(&ptr,ip_str      ,NULL)) ++count;
 312         if (next_token(&ptr,nb_flags_str,NULL)) ++count;
 313
 314         if (count <= 0) continue;
 315
 316         if (count != 4) {
 317           DEBUG(0,("Ill formed wins line"));
 318           DEBUG(0,("[%s]: name#type abs_time ip nb_flags\n",line));
 319           continue;
 320         }
 321
 322       /* Deal with SELF or REGISTER name encoding. Default is REGISTER
 323          for compatibility with old nmbds. */
 324       if(nb_flags_str[strlen(nb_flags_str)-1] == 'S')
 325       {
 326         DEBUG(5,("Ignoring SELF name %s\n", line));
 327         continue;
 328       }
 329
 330       if(nb_flags_str[strlen(nb_flags_str)-1] == 'R')
 331         nb_flags_str[strlen(nb_flags_str)-1] = '\0';
 332
 333       /* netbios name. # divides the name from the type (hex): netbios#xx */
 334       pstrcpy(name,name_str);
 335
 336       p = strchr(name,'#');
 337
 338       if (p) {
 339             *p = 0;
 340             sscanf(p+1,"%x",&type);
 341       }
 342
 343       /* decode the netbios flags (hex) and the time-to-die (seconds) */
 344           sscanf(nb_flags_str,"%x",&nb_flags);
 345           sscanf(ttd_str,"%ld",&ttd);
 346
 347           ipaddr = *interpret_addr2(ip_str);
 348
 349       if (ip_equal(ipaddr,ipzero)) {
 350          source = SELF;
 351       }
 352       else
 353       {
 354          source = REGISTER;
 355       }
 356
 357       DEBUG(4, ("add WINS line: %s#%02x %ld %s %2x\n",
 358                name,type, ttd, inet_ntoa(ipaddr), nb_flags));
 359
 360       /* add all entries that have 60 seconds or more to live */
 361       if (ttd - 60 > time(NULL) || ttd == 0)
 362       {
 363         time_t t = (ttd?ttd-time(NULL):0) / 3;
 364
 365         /* add netbios entry read from the wins.dat file. IF it's ok */
 366         add_netbios_entry(d,name,type,nb_flags,t,source,ipaddr,True);
 367       }
 368     }
 369
 370   fclose(f);
 371 }
 372
 373
 374 /****************************************************************************
 375   remove an entry from the name list
 376   ****************************************************************************/
 377 void remove_netbios_name(struct subnet_record *d,
 378                         char *name,int type, enum name_source source)
 379 {
 380   struct nmb_name nn;
 381   struct name_record *n;
 382
 383   make_nmb_name(&nn, name, type, scope);
 384   n = find_name_on_subnet(d, &nn, FIND_ANY_NAME);
 385
 386   if (n && n->source == source) remove_name(d,n);
 387 }
 388
 389
 390 /****************************************************************************
 391   add an entry to the name list.
 392
 393   this is a multi-purpose function.
 394
 395   it adds samba's own names in to its records on each interface, keeping a
 396   record of whether it is a master browser, domain master, or WINS server.
 397
 398   it also keeps a record of WINS entries.
 399
 400   ****************************************************************************/
 401 struct name_record *add_netbios_entry(struct subnet_record *d,
 402                 char *name, int type, int nb_flags, int ttl,
 403                 enum name_source source, struct in_addr ip, BOOL new_only)
 404 {
 405   struct name_record *n;
 406   struct name_record *n2=NULL;
 407   BOOL self = (source == SELF) ? FIND_SELF_NAME : FIND_ANY_NAME;
 408   /* It's a WINS add if we're adding to the wins_client_subnet. */
 409   BOOL wins = ( wins_client_subnet && (d == wins_client_subnet));
 410
 411   if(d == NULL)
 412   {
 413     DEBUG(0,("add_netbios_entry: called with NULL subnet record. This is a bug - \
 414 please report this.!\n"));
 415     return NULL;
 416   }
 417
 418   if (!self)
 419   {
 420     if (!wins && (type != 0x1b))
 421     {
 422        /* the only broadcast (non-WINS) names we are adding are ours
 423           (SELF) and Domain Master type names */
 424        return NULL;
 425     }
 426     if(wins && (type == 0x1d))
 427     {
 428       /* Do not allow any 0x1d names to be registered in a WINS,
 429          database although we return success for them.
 430        */
 431       return NULL;
 432     }
 433   }
 434
 435   n = (struct name_record *)malloc(sizeof(*n));
 436   if (!n) return(NULL);
 437
 438   bzero((char *)n,sizeof(*n));
 439
 440   n->num_ips = 1; /* XXXX ONLY USE THIS FUNCTION FOR ONE ENTRY */
 441   n->ip_flgs = (struct nmb_ip*)malloc(sizeof(*n->ip_flgs) * n->num_ips);
 442   if (!n->ip_flgs)
 443   {
 444      free(n);
 445      return NULL;
 446   }
 447
 448   bzero((char *)n->ip_flgs, sizeof(*n->ip_flgs) * n->num_ips);
 449
 450   make_nmb_name(&n->name,name,type,scope);
 451
 452   if ((n2 = find_name_on_subnet(d, &n->name, self)))
 453   {
 454     free(n->ip_flgs);
 455     free(n);
 456     if (new_only || (n2->source==SELF && source!=SELF)) return n2;
 457     n = n2;
 458   }
 459
 460   if (ttl)
 461      n->death_time = time(NULL)+ttl*3;
 462   n->refresh_time = time(NULL)+GET_TTL(ttl);
 463
 464   /* XXXX only one entry expected with this function */
 465   n->ip_flgs[0].ip = ip;
 466   n->ip_flgs[0].nb_flags = nb_flags;
 467
 468   n->source = source;
 469
 470   if (!n2) add_name(d,n);
 471
 472   DEBUG(3,("Added netbios name %s at %s ttl=%d nb_flags=%2x to interface %s\n",
 473            namestr(&n->name),inet_ntoa(ip),ttl,nb_flags,
 474            wins ? "WINS" : (char *)inet_ntoa(d->bcast_ip)));
 475
 476   return(n);
 477 }
 478
 479
 480 /*******************************************************************
 481   expires old names in the namelist
 482   ******************************************************************/
 483 void expire_names(time_t t)
 484 {
 485   struct name_record *n;
 486   struct name_record *next;
 487   struct subnet_record *d;
 488
 489   /* expire old names */
 490   for (d = FIRST_SUBNET; d; d = NEXT_SUBNET_INCLUDING_WINS(d))
 491   {
 492     for (n = d->namelist; n; n = next)
 493     {
 494       next = n->next;
 495       if (n->death_time && n->death_time < t)
 496       {
 497         if (n->source == SELF)
 498         {
 499           DEBUG(3,("not expiring SELF name %s\n", namestr(&n->name)));
 500                     n->death_time += 300;
 501           continue;
 502         }
 503         DEBUG(3,("Removing dead name %s\n", namestr(&n->name)));
 504
 505         if (n->prev) n->prev->next = n->next;
 506         if (n->next) n->next->prev = n->prev;
 507
 508         if (d->namelist == n) d->namelist = n->next;
 509
 510         if(n->ip_flgs != NULL)
 511           free(n->ip_flgs);
 512         free(n);
 513       }
 514     }
 515   }
 516 }
 517
 518