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 nbtd_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 **addresses)
  36 {
  37         struct nbt_name_packet *packet;
  38         size_t num_addresses = str_list_length(addresses);
  39         int i;
  40
  41         if (num_addresses == 0) {
  42                 DEBUG(3,("No addresses in name query reply - failing\n"));
  43                 return;
  44         }
  45
  46         packet = talloc_zero(nbtsock, struct nbt_name_packet);
  47         if (packet == NULL) return;
  48
  49         packet->name_trn_id = request_packet->name_trn_id;
  50         packet->ancount = 1;
  51         packet->operation =
  52                 NBT_FLAG_REPLY |
  53                 NBT_OPCODE_QUERY |
  54                 NBT_FLAG_AUTHORITIVE |
  55                 NBT_FLAG_RECURSION_DESIRED |
  56                 NBT_FLAG_RECURSION_AVAIL;
  57
  58         packet->answers = talloc_array(packet, struct nbt_res_rec, 1);
  59         if (packet->answers == NULL) goto failed;
  60
  61         packet->answers[0].name     = *name;
  62         packet->answers[0].rr_type  = NBT_QTYPE_NETBIOS;
  63         packet->answers[0].rr_class = NBT_QCLASS_IP;
  64         packet->answers[0].ttl      = ttl;
  65         packet->answers[0].rdata.netbios.length = num_addresses*6;
  66         packet->answers[0].rdata.netbios.addresses =
  67                 talloc_array(packet->answers, struct nbt_rdata_address, num_addresses);
  68         if (packet->answers[0].rdata.netbios.addresses == NULL) goto failed;
  69
  70         for (i=0;i<num_addresses;i++) {
  71                 struct nbt_rdata_address *addr =
  72                         &packet->answers[0].rdata.netbios.addresses[i];
  73                 addr->nb_flags = nb_flags;
  74                 addr->ipaddr = talloc_strdup(packet->answers, addresses[i]);
  75                 if (addr->ipaddr == NULL) goto failed;
  76         }
  77
  78         DEBUG(7,("Sending name query reply for %s<%02x> at %s to %s:%d\n",
  79                  name->name, name->type, src_address, addresses[0], src_port));
  80
  81         nbt_name_reply_send(nbtsock, src_address, src_port, packet);
  82
  83 failed:
  84         talloc_free(packet);
  85 }
  86
  87
  88 /*
  89   answer a name query
  90 */
  91 void nbtd_request_query(struct nbt_name_socket *nbtsock,
  92                         struct nbt_name_packet *packet,
  93                         const char *src_address, int src_port)
  94 {
  95         struct nbtd_iface_name *iname;
  96         struct nbt_name *name;
  97         struct nbtd_interface *iface = talloc_get_type(nbtsock->incoming.private,
  98                                                        struct nbtd_interface);
  99
 100         /* see if its a node status query */
 101         if (packet->qdcount == 1 &&
 102             packet->questions[0].question_type == NBT_QTYPE_STATUS) {
 103                 nbtd_query_status(nbtsock, packet, src_address, src_port);
 104                 return;
 105         }
 106
 107         NBT_ASSERT_PACKET(packet, src_address, packet->qdcount == 1);
 108         NBT_ASSERT_PACKET(packet, src_address, packet->questions[0].question_type == NBT_QTYPE_NETBIOS);
 109         NBT_ASSERT_PACKET(packet, src_address, packet->questions[0].question_class == NBT_QCLASS_IP);
 110
 111         /* see if we have the requested name on this interface */
 112         name = &packet->questions[0].name;
 113
 114         iname = nbtd_find_iname(iface, name, 0);
 115         if (iname == NULL) {
 116                 DEBUG(7,("Query for %s<%02x> from %s - not found on %s\n",
 117                          name->name, name->type, src_address, iface->ip_address));
 118                 return;
 119         }
 120
 121         /* if the name is not yet active and its a broadcast query then
 122            ignore it for now */
 123         if (!(iname->nb_flags & NBT_NM_ACTIVE) &&
 124             (packet->operation & NBT_FLAG_BROADCAST)) {
 125                 DEBUG(7,("Query for %s<%02x> from %s - name not active yet on %s\n",
 126                          name->name, name->type, src_address, iface->ip_address));
 127                 return;
 128         }
 129
 130         nbtd_name_query_reply(nbtsock, packet, src_address, src_port,
 131                               &iname->name, iname->ttl, iname->nb_flags,
 132                               nbtd_address_list(iface, packet));
 133 }