source/nbt_server/nodestatus.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    answer node status 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 status reply
  30 */
  31 static void nbtd_node_status_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,
  35                                    struct nbtd_interface *iface)
  36 {
  37         struct nbt_name_packet *packet;
  38         uint32_t name_count;
  39         struct nbtd_iface_name *iname;
  40
  41         /* work out how many names to send */
  42         name_count = 0;
  43         for (iname=iface->names;iname;iname=iname->next) {
  44                 if ((iname->nb_flags & NBT_NM_ACTIVE) &&
  45                     strcmp(iname->name.name, "*") != 0) {
  46                         name_count++;
  47                 }
  48         }
  49
  50         packet = talloc_zero(nbtsock, struct nbt_name_packet);
  51         if (packet == NULL) return;
  52
  53         packet->name_trn_id = request_packet->name_trn_id;
  54         packet->ancount = 1;
  55         packet->operation = NBT_OPCODE_QUERY | NBT_FLAG_REPLY | NBT_FLAG_AUTHORITIVE;
  56
  57         packet->answers = talloc_array(packet, struct nbt_res_rec, 1);
  58         if (packet->answers == NULL) goto failed;
  59
  60         packet->answers[0].name     = *name;
  61         packet->answers[0].rr_type  = NBT_QTYPE_STATUS;
  62         packet->answers[0].rr_class = NBT_QCLASS_IP;
  63         packet->answers[0].ttl      = 0;
  64         packet->answers[0].rdata.status.num_names = name_count;
  65         packet->answers[0].rdata.status.names = talloc_array(packet->answers,
  66                                                              struct nbt_status_name, name_count);
  67         if (packet->answers[0].rdata.status.names == NULL) goto failed;
  68
  69         name_count = 0;
  70         for (iname=iface->names;iname;iname=iname->next) {
  71                 if ((iname->nb_flags & NBT_NM_ACTIVE) &&
  72                     strcmp(iname->name.name, "*") != 0) {
  73                         struct nbt_status_name *n = &packet->answers[0].rdata.status.names[name_count];
  74                         n->name = talloc_asprintf(packet->answers, "%-15s", iname->name.name);
  75                         if (n->name == NULL) goto failed;
  76                         n->type     = iname->name.type;
  77                         n->nb_flags = iname->nb_flags;
  78                         name_count++;
  79                 }
  80         }
  81         /* we deliberately don't fill in the statistics structure as
  82            it could lead to giving attackers too much information */
  83         ZERO_STRUCT(packet->answers[0].rdata.status.statistics);
  84
  85         DEBUG(7,("Sending node status reply for %s to %s:%d\n",
  86                  nbt_name_string(packet, name), src_address, src_port));
  87
  88         nbt_name_reply_send(nbtsock, src_address, src_port, packet);
  89
  90 failed:
  91         talloc_free(packet);
  92 }
  93
  94
  95 /*
  96   answer a node status query
  97 */
  98 void nbtd_query_status(struct nbt_name_socket *nbtsock,
  99                        struct nbt_name_packet *packet,
 100                        const char *src_address, int src_port)
 101 {
 102         struct nbt_name *name;
 103         struct nbtd_iface_name *iname;
 104         struct nbtd_interface *iface = talloc_get_type(nbtsock->incoming.private,
 105                                                        struct nbtd_interface);
 106
 107         NBTD_ASSERT_PACKET(packet, src_address, packet->qdcount == 1);
 108         NBTD_ASSERT_PACKET(packet, src_address, packet->questions[0].question_type == NBT_QTYPE_STATUS);
 109         NBTD_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, NBT_NM_ACTIVE);
 115         if (iname == NULL) {
 116                 DEBUG(7,("Node status query for %s from %s - not found on %s\n",
 117                          nbt_name_string(packet, name), src_address, iface->ip_address));
 118                 return;
 119         }
 120
 121         nbtd_node_status_reply(nbtsock, packet, src_address, src_port,
 122                                &iname->name, iface);
 123 }