source/namedbsubnet.c

   1 /*
   2    Unix SMB/Netbios implementation.
   3    Version 1.9.
   4    NBT netbios routines and daemon - version 2
   5    Copyright (C) Andrew Tridgell 1994-1996
   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    Revision History:
  22
  23    14 jan 96: lkcl@pires.co.uk
  24    added multiple workgroup domain master support
  25
  26    04 jul 96: lkcl@pires.co.uk
  27    created module namedbsubnet containing subnet database functions
  28
  29 */
  30
  31 #include "includes.h"
  32 #include "smb.h"
  33
  34 extern int ClientNMB;
  35 extern int ClientDGRAM;
  36
  37 extern int DEBUGLEVEL;
  38
  39 extern struct in_addr ipgrp;
  40 extern struct in_addr ipzero;
  41
  42 extern pstring myname;
  43
  44 BOOL updatedlists = True;
  45 int updatecount = 0;
  46
  47 /* local interfaces structure */
  48 extern struct interface *local_interfaces;
  49
  50 /* this is our domain/workgroup/server database */
  51 struct subnet_record *subnetlist = NULL;
  52
  53 extern uint16 nb_type; /* samba's NetBIOS name type */
  54
  55 /****************************************************************************
  56   add a domain into the list
  57   **************************************************************************/
  58 static void add_subnet(struct subnet_record *d)
  59 {
  60   struct subnet_record *d2;
  61
  62   if (!subnetlist)
  63   {
  64     subnetlist = d;
  65     d->prev = NULL;
  66     d->next = NULL;
  67     return;
  68   }
  69
  70   for (d2 = subnetlist; d2->next; d2 = d2->next);
  71
  72   d2->next = d;
  73   d->next = NULL;
  74   d->prev = d2;
  75 }
  76
  77
  78 /****************************************************************************
  79   find a subnet in the subnetlist
  80   **************************************************************************/
  81 struct subnet_record *find_subnet(struct in_addr bcast_ip)
  82 {
  83   struct subnet_record *d;
  84   struct in_addr wins_ip = ipgrp;
  85
  86   /* search through subnet list for broadcast/netmask that matches
  87      the source ip address. a subnet 255.255.255.255 represents the
  88      WINS list. */
  89
  90         for (d = subnetlist; d; d = d->next)
  91     {
  92         if (ip_equal(bcast_ip, wins_ip))
  93             {
  94                         if (ip_equal(bcast_ip, d->bcast_ip))
  95                         {
  96                                 return d;
  97                         }
  98         }
  99         else if (same_net(bcast_ip, d->bcast_ip, d->mask_ip))
 100             {
 101                         if (!ip_equal(d->bcast_ip, wins_ip))
 102                         {
 103                                 return d;
 104                         }
 105             }
 106     }
 107
 108         return (NULL);
 109 }
 110
 111
 112 /****************************************************************************
 113   finds the appropriate subnet structure. directed packets (non-bcast) are
 114   assumed to come from a point-to-point (P or M node), and so the subnet we
 115   return in this instance is the WINS 'pseudo-subnet' with ip 255.255.255.255
 116   ****************************************************************************/
 117 struct subnet_record *find_req_subnet(struct in_addr ip, BOOL bcast)
 118 {
 119   if (bcast)
 120   {
 121     /* identify the subnet the broadcast request came from */
 122     return find_subnet(*iface_bcast(ip));
 123   }
 124   /* find the subnet under the pseudo-ip of 255.255.255.255 */
 125   return find_subnet(ipgrp);
 126 }
 127
 128
 129 /****************************************************************************
 130   create a domain entry
 131   ****************************************************************************/
 132 static struct subnet_record *make_subnet(struct in_addr bcast_ip, struct in_addr mask_ip)
 133 {
 134   struct subnet_record *d;
 135   d = (struct subnet_record *)malloc(sizeof(*d));
 136
 137   if (!d) return(NULL);
 138
 139   bzero((char *)d,sizeof(*d));
 140
 141   DEBUG(4, ("making subnet %s ", inet_ntoa(bcast_ip)));
 142   DEBUG(4, ("%s\n", inet_ntoa(mask_ip)));
 143
 144   d->bcast_ip = bcast_ip;
 145   d->mask_ip  = mask_ip;
 146   d->workgrouplist = NULL;
 147
 148   add_subnet(d);
 149
 150   return d;
 151 }
 152
 153
 154 /****************************************************************************
 155   add the remote interfaces from lp_interfaces()
 156   to the netbios subnet database.
 157   ****************************************************************************/
 158 void add_subnet_interfaces(void)
 159 {
 160         struct interface *i;
 161
 162         /* loop on all local interfaces */
 163         for (i = local_interfaces; i; i = i->next)
 164         {
 165                 /* add the interface into our subnet database */
 166                 if (!find_subnet(i->bcast))
 167                 {
 168                   make_subnet(i->bcast,i->nmask);
 169                 }
 170         }
 171
 172         /* add the pseudo-ip interface for WINS: 255.255.255.255 */
 173         if (lp_wins_support() || (*lp_wins_server()))
 174     {
 175                 struct in_addr wins_bcast = ipgrp;
 176                 struct in_addr wins_nmask = ipzero;
 177                 make_subnet(wins_bcast, wins_nmask);
 178     }
 179 }
 180
 181
 182
 183 /****************************************************************************
 184   add the default workgroup into my domain
 185   **************************************************************************/
 186 void add_my_subnets(char *group)
 187 {
 188   struct interface *i;
 189
 190   /* add or find domain on our local subnet, in the default workgroup */
 191
 192   if (*group == '*') return;
 193
 194         /* the coding choice is up to you, andrew: i can see why you don't want
 195        global access to the local_interfaces structure: so it can't get
 196        messed up! */
 197     for (i = local_interfaces; i; i = i->next)
 198     {
 199       add_subnet_entry(i->bcast,i->nmask,group, True, False);
 200     }
 201 }
 202
 203
 204 /****************************************************************************
 205   add a domain entry. creates a workgroup, if necessary, and adds the domain
 206   to the named a workgroup.
 207   ****************************************************************************/
 208 struct subnet_record *add_subnet_entry(struct in_addr bcast_ip,
 209                                        struct in_addr mask_ip,
 210                                        char *name, BOOL add, BOOL lmhosts)
 211 {
 212   struct subnet_record *d;
 213
 214   /* XXXX andrew: struct in_addr ip appears not to be referenced at all except
 215      in the DEBUG comment. i assume that the DEBUG comment below actually
 216      intends to refer to bcast_ip? i don't know.
 217
 218   struct in_addr ip = ipgrp;
 219
 220   */
 221
 222   if (zero_ip(bcast_ip))
 223     bcast_ip = *iface_bcast(bcast_ip);
 224
 225   /* add the domain into our domain database */
 226   if ((d = find_subnet(bcast_ip)) ||
 227       (d = make_subnet(bcast_ip, mask_ip)))
 228     {
 229       struct work_record *w = find_workgroupstruct(d, name, add);
 230
 231       if (!w) return NULL;
 232
 233       /* add WORKGROUP(1e) and WORKGROUP(00) entries into name database
 234          or register with WINS server, if it's our workgroup */
 235       if (strequal(lp_workgroup(), name))
 236         {
 237           add_my_name_entry(d,name,0x1e,nb_type|NB_ACTIVE|NB_GROUP);
 238           add_my_name_entry(d,name,0x0 ,nb_type|NB_ACTIVE|NB_GROUP);
 239         }
 240       /* add samba server name to workgroup list. don't add
 241          lmhosts server entries to local interfaces */
 242       if (strequal(lp_workgroup(), name))
 243       {
 244         add_server_entry(d,w,myname,w->ServerType,0,lp_serverstring(),True);
 245         DEBUG(3,("Added server name entry %s at %s\n",
 246                   name,inet_ntoa(bcast_ip)));
 247       }
 248
 249       return d;
 250     }
 251   return NULL;
 252 }
 253
 254
 255 /*******************************************************************
 256   write out browse.dat
 257   ******************************************************************/
 258 void write_browse_list(time_t t)
 259 {
 260   struct subnet_record *d;
 261   pstring fname,fnamenew;
 262   FILE *f;
 263
 264   static time_t lasttime = 0;
 265
 266   if (!lasttime) lasttime = t;
 267   if (!updatedlists || t - lasttime < 5) return;
 268
 269   lasttime = t;
 270   updatedlists = False;
 271   updatecount++;
 272
 273   dump_names();
 274   dump_workgroups();
 275
 276   strcpy(fname,lp_lockdir());
 277   trim_string(fname,NULL,"/");
 278   strcat(fname,"/");
 279   strcat(fname,SERVER_LIST);
 280   strcpy(fnamenew,fname);
 281   strcat(fnamenew,".");
 282
 283   f = fopen(fnamenew,"w");
 284
 285   if (!f)
 286     {
 287       DEBUG(4,("Can't open %s - %s\n",fnamenew,strerror(errno)));
 288       return;
 289     }
 290
 291   for (d = subnetlist; d ; d = d->next)
 292     {
 293       struct work_record *work;
 294       for (work = d->workgrouplist; work ; work = work->next)
 295         {
 296           struct server_record *s;
 297           for (s = work->serverlist; s ; s = s->next)
 298             {
 299               fstring tmp;
 300
 301               /* don't list domains I don't have a master for */
 302               if ((s->serv.type & SV_TYPE_DOMAIN_ENUM) && !s->serv.comment[0])
 303                 {
 304                   continue;
 305                 }
 306
 307               /* output server details, plus what workgroup/domain
 308                  they're in. without the domain information, the
 309                  combined list of all servers in all workgroups gets
 310                  sent to anyone asking about any workgroup! */
 311
 312               sprintf(tmp, "\"%s\"", s->serv.name);
 313               fprintf(f, "%-25s ", tmp);
 314               fprintf(f, "%08x ", s->serv.type);
 315               sprintf(tmp, "\"%s\" ", s->serv.comment);
 316               fprintf(f, "%-30s", tmp);
 317               fprintf(f, "\"%s\"\n", work->work_group);
 318             }
 319         }
 320     }
 321
 322   fclose(f);
 323   unlink(fname);
 324   chmod(fnamenew,0644);
 325   rename(fnamenew,fname);
 326   DEBUG(3,("Wrote browse list %s\n",fname));
 327 }
 328