source/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   send a name query reply
  30 */
  31 static void nbt_name_query_reply(struct nbt_name_socket *nbtsock,
  32                                  struct nbt_name_packet *request_packet,
  33                                  const char *src_address, int src_port,
  34                                  struct nbt_name *name, uint32_t ttl,
  35                                  uint16_t nb_flags, const char *address)
  36 {
  37         struct nbt_name_packet *packet;
  38
  39         packet = talloc_zero(nbtsock, struct nbt_name_packet);
  40         if (packet == NULL) return;
  41
  42         packet->name_trn_id = request_packet->name_trn_id;
  43         packet->ancount = 1;
  44         packet->operation =
  45                 NBT_FLAG_REPLY |
  46                 NBT_OPCODE_QUERY |
  47                 NBT_FLAG_AUTHORITIVE |
  48                 NBT_FLAG_RECURSION_DESIRED |
  49                 NBT_FLAG_RECURSION_AVAIL;
  50
  51         packet->answers = talloc_array(packet, struct nbt_res_rec, 1);
  52         if (packet->answers == NULL) goto failed;
  53
  54         packet->answers[0].name     = *name;
  55         packet->answers[0].rr_type  = NBT_QTYPE_NETBIOS;
  56         packet->answers[0].rr_class = NBT_QCLASS_IP;
  57         packet->answers[0].ttl      = ttl;
  58         packet->answers[0].rdata.netbios.length = 6;
  59         packet->answers[0].rdata.netbios.addresses = talloc_array(packet->answers,
  60                                                             struct nbt_rdata_address, 1);
  61         if (packet->answers[0].rdata.netbios.addresses == NULL) goto failed;
  62         packet->answers[0].rdata.netbios.addresses[0].nb_flags = nb_flags;
  63         packet->answers[0].rdata.netbios.addresses[0].ipaddr =
  64                 talloc_strdup(packet->answers, address);
  65         if (packet->answers[0].rdata.netbios.addresses[0].ipaddr == NULL) goto failed;
  66
  67         DEBUG(7,("Sending name query reply for %s<%02x> at %s to %s:%d\n",
  68                  name->name, name->type, src_address, address, src_port));
  69
  70         nbt_name_reply_send(nbtsock, src_address, src_port, packet);
  71
  72 failed:
  73         talloc_free(packet);
  74 }
  75
  76
  77 /*
  78   answer a name query
  79 */
  80 void nbt_request_query(struct nbt_name_socket *nbtsock,
  81                        struct nbt_name_packet *packet,
  82                        const char *src_address, int src_port)
  83 {
  84         struct nbt_iface_name *iname;
  85         struct nbt_name *name;
  86         struct nbt_interface *iface = talloc_get_type(nbtsock->incoming.private,
  87                                                       struct nbt_interface);
  88
  89         /* see if its a node status query */
  90         if (packet->qdcount == 1 &&
  91             packet->questions[0].question_type == NBT_QTYPE_STATUS) {
  92                 nbt_query_status(nbtsock, packet, src_address, src_port);
  93                 return;
  94         }
  95
  96         /* if its a WINS query then direct to our WINS server */
  97         if ((packet->operation & NBT_FLAG_RECURSION_DESIRED) &&
  98             !(packet->operation & NBT_FLAG_BROADCAST)) {
  99                 nbt_query_wins(nbtsock, packet, src_address, src_port);
 100                 return;
 101         }
 102
 103         NBT_ASSERT_PACKET(packet, src_address, packet->qdcount == 1);
 104         NBT_ASSERT_PACKET(packet, src_address, packet->questions[0].question_type == NBT_QTYPE_NETBIOS);
 105         NBT_ASSERT_PACKET(packet, src_address, packet->questions[0].question_class == NBT_QCLASS_IP);
 106
 107         /* see if we have the requested name on this interface */
 108         name = &packet->questions[0].name;
 109
 110         iname = nbt_find_iname(iface, name, NBT_NM_ACTIVE);
 111         if (iname == NULL) {
 112                 DEBUG(7,("Query for %s<%02x> from %s - not found on %s\n",
 113                          name->name, name->type, src_address, iface->ip_address));
 114                 return;
 115         }
 116
 117         nbt_name_query_reply(nbtsock, packet, src_address, src_port,
 118                              &iname->name, iname->ttl, iname->nb_flags,
 119                              iface->ip_address);
 120 }