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               return(d);
 102             }
 103     }
 104
 105   return (NULL);
 106 }
 107
 108
 109 /****************************************************************************
 110   finds the appropriate subnet structure. directed packets (non-bcast) are
 111   assumed to come from a point-to-point (P or M node), and so the subnet we
 112   return in this instance is the WINS 'pseudo-subnet' with ip 255.255.255.255
 113   ****************************************************************************/
 114 struct subnet_record *find_req_subnet(struct in_addr ip, BOOL bcast)
 115 {
 116   if (bcast)
 117   {
 118     /* identify the subnet the broadcast request came from */
 119     return find_subnet(*iface_bcast(ip));
 120   }
 121   /* find the subnet under the pseudo-ip of 255.255.255.255 */
 122   return find_subnet(ipgrp);
 123 }
 124
 125
 126 /****************************************************************************
 127   create a domain entry
 128   ****************************************************************************/
 129 static struct subnet_record *make_subnet(struct in_addr bcast_ip, struct in_addr mask_ip)
 130 {
 131   struct subnet_record *d;
 132   d = (struct subnet_record *)malloc(sizeof(*d));
 133
 134   if (!d) return(NULL);
 135
 136   bzero((char *)d,sizeof(*d));
 137
 138   DEBUG(4, ("making subnet %s ", inet_ntoa(bcast_ip)));
 139   DEBUG(4, ("%s\n", inet_ntoa(mask_ip)));
 140
 141   d->bcast_ip = bcast_ip;
 142   d->mask_ip  = mask_ip;
 143   d->workgrouplist = NULL;
 144
 145   add_subnet(d);
 146
 147   return d;
 148 }
 149
 150
 151 /****************************************************************************
 152   add the remote interfaces from lp_interfaces()
 153   to the netbios subnet database.
 154   ****************************************************************************/
 155 void add_subnet_interfaces(void)
 156 {
 157         struct interface *i;
 158
 159         /* loop on all local interfaces */
 160         for (i = local_interfaces; i; i = i->next)
 161         {
 162                 /* add the interface into our subnet database */
 163                 if (!find_subnet(i->bcast))
 164                 {
 165                   make_subnet(i->bcast,i->nmask);
 166                 }
 167         }
 168
 169         /* add the pseudo-ip interface for WINS: 255.255.255.255 */
 170         if (lp_wins_support() || (*lp_wins_server()))
 171     {
 172                 struct in_addr wins_bcast = ipgrp;
 173                 struct in_addr wins_nmask = ipzero;
 174                 make_subnet(wins_bcast, wins_nmask);
 175     }
 176 }
 177
 178
 179
 180 /****************************************************************************
 181   add the default workgroup into my domain
 182   **************************************************************************/
 183 void add_my_subnets(char *group)
 184 {
 185   struct interface *i;
 186
 187   /* add or find domain on our local subnet, in the default workgroup */
 188
 189   if (*group == '*') return;
 190
 191         /* the coding choice is up to you, andrew: i can see why you don't want
 192        global access to the local_interfaces structure: so it can't get
 193        messed up! */
 194     for (i = local_interfaces; i; i = i->next)
 195     {
 196       add_subnet_entry(i->bcast,i->nmask,group, True, False);
 197     }
 198 }
 199
 200
 201 /****************************************************************************
 202   add a domain entry. creates a workgroup, if necessary, and adds the domain
 203   to the named a workgroup.
 204   ****************************************************************************/
 205 struct subnet_record *add_subnet_entry(struct in_addr bcast_ip,
 206                                        struct in_addr mask_ip,
 207                                        char *name, BOOL add, BOOL lmhosts)
 208 {
 209   struct subnet_record *d;
 210
 211   /* XXXX andrew: struct in_addr ip appears not to be referenced at all except
 212      in the DEBUG comment. i assume that the DEBUG comment below actually
 213      intends to refer to bcast_ip? i don't know.
 214
 215   struct in_addr ip = ipgrp;
 216
 217   */
 218
 219   if (zero_ip(bcast_ip))
 220     bcast_ip = *iface_bcast(bcast_ip);
 221
 222   /* add the domain into our domain database */
 223   if ((d = find_subnet(bcast_ip)) ||
 224       (d = make_subnet(bcast_ip, mask_ip)))
 225     {
 226       struct work_record *w = find_workgroupstruct(d, name, add);
 227
 228       if (!w) return NULL;
 229
 230       /* add WORKGROUP(1e) and WORKGROUP(00) entries into name database
 231          or register with WINS server, if it's our workgroup */
 232       if (strequal(lp_workgroup(), name))
 233         {
 234           add_my_name_entry(d,name,0x1e,nb_type|NB_ACTIVE|NB_GROUP);
 235           add_my_name_entry(d,name,0x0 ,nb_type|NB_ACTIVE|NB_GROUP);
 236         }
 237       /* add samba server name to workgroup list. don't add
 238          lmhosts server entries to local interfaces */
 239       if (strequal(lp_workgroup(), name))
 240       {
 241         add_server_entry(d,w,myname,w->ServerType,0,lp_serverstring(),True);
 242         DEBUG(3,("Added server name entry %s at %s\n",
 243                   name,inet_ntoa(bcast_ip)));
 244       }
 245
 246       return d;
 247     }
 248   return NULL;
 249 }
 250
 251
 252 /*******************************************************************
 253   write out browse.dat
 254   ******************************************************************/
 255 void write_browse_list(void)
 256 {
 257   struct subnet_record *d;
 258   pstring fname,fnamenew;
 259   FILE *f;
 260
 261   static time_t lasttime = 0;
 262   time_t t = time(NULL);
 263
 264   if (!lasttime) lasttime = t;
 265   if (!updatedlists || t - lasttime < 5) return;
 266
 267   lasttime = t;
 268   updatedlists = False;
 269   updatecount++;
 270
 271   dump_names();
 272   dump_workgroups();
 273
 274   strcpy(fname,lp_lockdir());
 275   trim_string(fname,NULL,"/");
 276   strcat(fname,"/");
 277   strcat(fname,SERVER_LIST);
 278   strcpy(fnamenew,fname);
 279   strcat(fnamenew,".");
 280
 281   f = fopen(fnamenew,"w");
 282
 283   if (!f)
 284     {
 285       DEBUG(4,("Can't open %s - %s\n",fnamenew,strerror(errno)));
 286       return;
 287     }
 288
 289   for (d = subnetlist; d ; d = d->next)
 290     {
 291       struct work_record *work;
 292       for (work = d->workgrouplist; work ; work = work->next)
 293         {
 294           struct server_record *s;
 295           for (s = work->serverlist; s ; s = s->next)
 296             {
 297               fstring tmp;
 298
 299               /* don't list domains I don't have a master for */
 300               if ((s->serv.type & SV_TYPE_DOMAIN_ENUM) && !s->serv.comment[0])
 301                 {
 302                   continue;
 303                 }
 304
 305               /* output server details, plus what workgroup/domain
 306                  they're in. without the domain information, the
 307                  combined list of all servers in all workgroups gets
 308                  sent to anyone asking about any workgroup! */
 309
 310               sprintf(tmp, "\"%s\"", s->serv.name);
 311               fprintf(f, "%-25s ", tmp);
 312               fprintf(f, "%08x ", s->serv.type);
 313               sprintf(tmp, "\"%s\" ", s->serv.comment);
 314               fprintf(f, "%-30s", tmp);
 315               fprintf(f, "\"%s\"\n", work->work_group);
 316             }
 317         }
 318     }
 319
 320   fclose(f);
 321   unlink(fname);
 322   chmod(fnamenew,0644);
 323   rename(fnamenew,fname);
 324   DEBUG(3,("Wrote browse list %s\n",fname));
 325 }
 326