source/nbt_server/defense.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    defend our names against name registration requests
   5
   6    Copyright (C) Andrew Tridgell        2005
   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 #include "includes.h"
  24 #include "dlinklist.h"
  25 #include "system/network.h"
  26 #include "nbt_server/nbt_server.h"
  27
  28
  29 /*
  30   defend our registered names against registration or name refresh
  31   requests
  32 */
  33 void nbtd_request_defense(struct nbt_name_socket *nbtsock,
  34                           struct nbt_name_packet *packet,
  35                           const char *src_address, int src_port)
  36 {
  37         struct nbtd_iface_name *iname;
  38         struct nbt_name *name;
  39         struct nbtd_interface *iface = talloc_get_type(nbtsock->incoming.private,
  40                                                        struct nbtd_interface);
  41
  42         NBTD_ASSERT_PACKET(packet, src_address, packet->qdcount == 1);
  43         NBTD_ASSERT_PACKET(packet, src_address, packet->arcount == 1);
  44         NBTD_ASSERT_PACKET(packet, src_address,
  45                            packet->questions[0].question_type == NBT_QTYPE_NETBIOS);
  46         NBTD_ASSERT_PACKET(packet, src_address,
  47                            packet->questions[0].question_class == NBT_QCLASS_IP);
  48         NBTD_ASSERT_PACKET(packet, src_address,
  49                           packet->additional[0].rr_type == NBT_QTYPE_NETBIOS);
  50         NBTD_ASSERT_PACKET(packet, src_address,
  51                           packet->additional[0].rr_class == NBT_QCLASS_IP);
  52         NBTD_ASSERT_PACKET(packet, src_address,
  53                           packet->additional[0].rdata.netbios.length == 6);
  54
  55         /* see if we have the requested name on this interface */
  56         name = &packet->questions[0].name;
  57
  58         iname = nbtd_find_iname(iface, name, NBT_NM_ACTIVE);
  59         if (iname != NULL && !(iname->nb_flags & NBT_NM_GROUP)) {
  60                 DEBUG(2,("Defending name %s<%02x> on %s against %s\n",
  61                          name->name, name->type, iface->bcast_address, src_address));
  62                 nbtd_negative_name_registration_reply(nbtsock, packet,
  63                                                       src_address, src_port);
  64         } else {
  65                 nbtd_winsserver_request(nbtsock, packet, src_address, src_port);
  66         }
  67 }