source4/nbt_server/query.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    answer name queries
   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   answer a name query
  31 */
  32 void nbtd_request_query(struct nbt_name_socket *nbtsock,
  33                         struct nbt_name_packet *packet,
  34                         const char *src_address, int src_port)
  35 {
  36         struct nbtd_iface_name *iname;
  37         struct nbt_name *name;
  38         struct nbtd_interface *iface = talloc_get_type(nbtsock->incoming.private,
  39                                                        struct nbtd_interface);
  40
  41         /* see if its a node status query */
  42         if (packet->qdcount == 1 &&
  43             packet->questions[0].question_type == NBT_QTYPE_STATUS) {
  44                 nbtd_query_status(nbtsock, packet, src_address, src_port);
  45                 return;
  46         }
  47
  48         NBTD_ASSERT_PACKET(packet, src_address, packet->qdcount == 1);
  49         NBTD_ASSERT_PACKET(packet, src_address,
  50                            packet->questions[0].question_type == NBT_QTYPE_NETBIOS);
  51         NBTD_ASSERT_PACKET(packet, src_address,
  52                            packet->questions[0].question_class == NBT_QCLASS_IP);
  53
  54         /* see if we have the requested name on this interface */
  55         name = &packet->questions[0].name;
  56
  57         iname = nbtd_find_iname(iface, name, 0);
  58
  59         if (iname == NULL) {
  60                 /* don't send negative replies to broadcast queries */
  61                 if (packet->operation & NBT_FLAG_BROADCAST) {
  62                         return;
  63                 }
  64
  65                 /* if the name does not exist, then redirect to WINS
  66                    server if recursion has been asked for */
  67                 if (packet->operation & NBT_FLAG_RECURSION_DESIRED) {
  68                         nbtd_winsserver_request(nbtsock, packet, src_address, src_port);
  69                         return;
  70                 }
  71
  72                 /* otherwise send a negative reply */
  73                 nbtd_negative_name_query_reply(nbtsock, packet,
  74                                                src_address, src_port);
  75                 return;
  76         }
  77
  78         /* if the name is not yet active and its a broadcast query then
  79            ignore it for now */
  80         if (!(iname->nb_flags & NBT_NM_ACTIVE) &&
  81             (packet->operation & NBT_FLAG_BROADCAST)) {
  82                 DEBUG(7,("Query for %s<%02x> from %s - name not active yet on %s\n",
  83                          name->name, name->type, src_address, iface->ip_address));
  84                 return;
  85         }
  86
  87         nbtd_name_query_reply(nbtsock, packet, src_address, src_port,
  88                               &iname->name, iname->ttl, iname->nb_flags,
  89                               nbtd_address_list(iface, packet));
  90 }