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/*
Unix SMB/CIFS implementation.
defend our names against name registration requests
Copyright (C) Andrew Tridgell 2005
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include "includes.h"
#include "dlinklist.h"
#include "system/network.h"
#include "nbt_server/nbt_server.h"
/*
send a name defense reply
*/
static void nbtd_name_defense_reply(struct nbt_name_socket *nbtsock,
struct nbt_name_packet *request_packet,
const char *src_address, int src_port,
struct nbt_name *name, uint32_t ttl,
uint16_t nb_flags, const char *address)
{
struct nbt_name_packet *packet;
packet = talloc_zero(nbtsock, struct nbt_name_packet);
if (packet == NULL) return;
packet->name_trn_id = request_packet->name_trn_id;
packet->ancount = 1;
packet->operation =
NBT_FLAG_REPLY |
(request_packet->operation & NBT_OPCODE) |
NBT_FLAG_AUTHORITIVE |
NBT_FLAG_RECURSION_DESIRED |
NBT_FLAG_RECURSION_AVAIL |
NBT_RCODE_ACT;
packet->answers = talloc_array(packet, struct nbt_res_rec, 1);
if (packet->answers == NULL) goto failed;
packet->answers[0].name = *name;
packet->answers[0].rr_type = NBT_QTYPE_NETBIOS;
packet->answers[0].rr_class = NBT_QCLASS_IP;
packet->answers[0].ttl = ttl;
packet->answers[0].rdata.netbios.length = 6;
packet->answers[0].rdata.netbios.addresses =
talloc_array(packet->answers,
struct nbt_rdata_address, 1);
if (packet->answers[0].rdata.netbios.addresses == NULL) goto failed;
packet->answers[0].rdata.netbios.addresses[0].nb_flags = nb_flags;
packet->answers[0].rdata.netbios.addresses[0].ipaddr =
talloc_strdup(packet->answers, address);
if (packet->answers[0].rdata.netbios.addresses[0].ipaddr == NULL) goto failed;
DEBUG(7,("Sending name defense reply for %s<%02x> at %s to %s:%d\n",
name->name, name->type, src_address, address, src_port));
nbt_name_reply_send(nbtsock, src_address, src_port, packet);
failed:
talloc_free(packet);
}
/*
defend our registered names against registration or name refresh
requests
*/
void nbtd_request_defense(struct nbt_name_socket *nbtsock,
struct nbt_name_packet *packet,
const char *src_address, int src_port)
{
struct nbt_iface_name *iname;
struct nbt_name *name;
struct nbt_interface *iface = talloc_get_type(nbtsock->incoming.private,
struct nbt_interface);
NBT_ASSERT_PACKET(packet, src_address, packet->qdcount == 1);
NBT_ASSERT_PACKET(packet, src_address, packet->arcount == 1);
NBT_ASSERT_PACKET(packet, src_address,
packet->questions[0].question_type == NBT_QTYPE_NETBIOS);
NBT_ASSERT_PACKET(packet, src_address,
packet->questions[0].question_class == NBT_QCLASS_IP);
/* see if we have the requested name on this interface */
name = &packet->questions[0].name;
iname = nbtd_find_iname(iface, name, NBT_NM_ACTIVE);
if (iname != NULL) {
DEBUG(2,("Defending name %s<%02x> on %s against %s\n",
name->name, name->type, iface->bcast_address, src_address));
nbtd_name_defense_reply(nbtsock, packet, src_address, src_port,
&iname->name, iname->ttl, iname->nb_flags,
iface->ip_address);
}
}
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