2011-10-28 14:50:13 +00:00
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/******************************************************************************************************/
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/* packet-bt-dht.c
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* Routines for BT-DHT dissection
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* Copyright 2011, Xiao Xiangquan <xiaoxiangquan@gmail.com>
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*
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* $Id$
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*
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* A plugin for BT-DHT packet:
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*
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* Wireshark - Network traffic analyzer
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* By Gerald Combs <gerald@wireshark.org>
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* Copyright 1999 Gerald Combs
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version 2
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* of the License, or (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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2012-06-28 22:56:06 +00:00
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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
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2011-10-28 14:50:13 +00:00
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*/
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#include "config.h"
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2011-11-15 19:00:08 +00:00
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2011-10-28 14:50:13 +00:00
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#include <epan/packet.h>
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2011-11-15 19:00:08 +00:00
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#include <epan/conversation.h>
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2012-01-20 03:24:05 +00:00
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#include <epan/prefs.h>
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2011-10-28 14:50:13 +00:00
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/* Specifications: BEP-0005
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* http://www.bittorrent.org/beps/bep_0005.html
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*/
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static int proto_bt_dht = -1;
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static dissector_handle_t bt_dht_handle;
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2012-01-20 03:24:05 +00:00
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static gboolean bt_dht_enable_heuristic_dissection = FALSE; /* disabled by default since heuristic is weak */
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2011-10-28 14:50:13 +00:00
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/* fields */
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static int hf_bencoded_int = -1;
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static int hf_bencoded_string = -1;
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static int hf_bencoded_list = -1;
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static int hf_bencoded_dict = -1;
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static int hf_bencoded_dict_entry = -1;
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static int hf_bt_dht_error = -1;
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static int hf_bt_dht_peers = -1;
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static int hf_bt_dht_peer = -1;
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static int hf_bt_dht_nodes = -1;
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static int hf_bt_dht_node = -1;
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static int hf_bt_dht_id = -1;
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static int hf_ip = -1;
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static int hf_port = -1;
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static int hf_truncated_data = -1;
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/* tree types */
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static gint ett_bt_dht = -1;
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static gint ett_bencoded_list = -1;
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static gint ett_bencoded_dict = -1;
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static gint ett_bencoded_dict_entry = -1;
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static gint ett_bt_dht_error = -1;
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static gint ett_bt_dht_peers = -1;
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static gint ett_bt_dht_nodes = -1;
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/* some keys use short name in packet */
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static const value_string short_key_name_value_string[] = {
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2013-04-20 09:49:00 +00:00
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{ 'y', "Message type" },
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{ 'q', "Request type" },
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{ 'e', "Error" },
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{ 't', "Transaction ID" },
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{ 'v', "Version" },
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{ 'a', "Request arguments" },
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{ 'r', "Response values" },
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2011-10-28 14:50:13 +00:00
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{ 0, NULL }
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};
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/* some values use short name in packet */
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static const value_string short_val_name_value_string[] = {
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2013-04-20 09:49:00 +00:00
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{ 'q', "Request" },
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{ 'r', "Response" },
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{ 'e', "Error" },
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2011-10-28 14:50:13 +00:00
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{ 0, NULL }
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};
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2013-04-20 09:49:00 +00:00
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static const char dict_str[] = "Dictionary...";
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static const char list_str[] = "List...";
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2012-12-05 09:27:58 +00:00
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static inline int
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bencoded_string_length(tvbuff_t *tvb, guint *offset_ptr)
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{
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guint offset, start, len;
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offset = *offset_ptr;
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start = offset;
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while(tvb_get_guint8(tvb, offset) != ':')
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++offset;
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len = atoi(tvb_get_ephemeral_string(tvb, start, offset-start));
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++offset; /* skip the ':' */
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*offset_ptr = offset;
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return len;
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}
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2011-10-28 14:50:13 +00:00
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/*
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* dissect a bencoded string from tvb, start at offset. it's like "5:abcde"
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* *result will be the decoded value
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*/
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2012-01-20 03:24:05 +00:00
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static int
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2012-06-04 13:21:44 +00:00
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dissect_bencoded_string(tvbuff_t *tvb, packet_info _U_*pinfo, proto_tree *tree, guint offset, char **result, gboolean tohex, const char *label )
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2011-10-28 14:50:13 +00:00
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{
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guint string_len;
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2012-12-05 09:27:58 +00:00
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string_len = bencoded_string_length(tvb, &offset);
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2011-10-28 14:50:13 +00:00
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/* fill the return data */
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if( tohex )
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*result = tvb_bytes_to_str(tvb, offset, string_len );
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else
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2011-12-28 16:36:57 +00:00
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*result = tvb_get_ephemeral_string( tvb, offset, string_len );
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2011-10-28 14:50:13 +00:00
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proto_tree_add_string_format( tree, hf_bencoded_string, tvb, offset, string_len, *result, "%s: %s", label, *result );
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offset += string_len;
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return offset;
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}
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/*
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* dissect a bencoded integer from tvb, start at offset. it's like "i5673e"
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* *result will be the decoded value
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*/
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2012-01-20 03:24:05 +00:00
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static int
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2012-06-04 13:21:44 +00:00
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dissect_bencoded_int(tvbuff_t *tvb, packet_info _U_*pinfo, proto_tree *tree, guint offset, char **result, const char *label )
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2011-10-28 14:50:13 +00:00
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{
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guint start_offset;
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start_offset = offset;
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2012-01-20 03:24:05 +00:00
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/* we have confirmed that the first byte is 'i' */
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offset += 1;
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2011-10-28 14:50:13 +00:00
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while( tvb_get_guint8(tvb,offset)!='e' )
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2012-01-20 03:24:05 +00:00
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offset += 1;
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2011-10-28 14:50:13 +00:00
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2011-12-28 16:36:57 +00:00
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*result = tvb_get_ephemeral_string( tvb, offset, offset-start_offset-1 );
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2011-10-28 14:50:13 +00:00
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proto_tree_add_string_format( tree, hf_bencoded_int, tvb, offset, offset-start_offset-1, *result,
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"%s: %s", label, *result );
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2012-01-20 03:24:05 +00:00
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offset += 1;
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2011-10-28 14:50:13 +00:00
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return offset;
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}
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/* pre definition of dissect_bencoded_dict(), which is needed by dissect_bencoded_list() */
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2012-12-26 05:57:06 +00:00
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static int dissect_bencoded_dict(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, guint offset, const char *label );
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2011-10-28 14:50:13 +00:00
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/* dissect a bencoded list from tvb, start at offset. it's like "lXXXe", "X" is any bencoded thing */
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2012-01-20 03:24:05 +00:00
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static int
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2012-06-04 13:21:44 +00:00
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dissect_bencoded_list(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, guint offset, const char *label )
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2011-10-28 14:50:13 +00:00
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{
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proto_item *ti;
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proto_tree *sub_tree;
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2012-01-20 03:24:05 +00:00
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guint one_byte;
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char *result;
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2011-10-28 14:50:13 +00:00
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ti = proto_tree_add_none_format( tree, hf_bencoded_list, tvb, offset, 0, "%s: list...", label );
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sub_tree = proto_item_add_subtree( ti, ett_bencoded_list);
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/* skip the 'l' */
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2012-01-20 03:24:05 +00:00
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offset += 1;
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2011-10-28 14:50:13 +00:00
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while( (one_byte=tvb_get_guint8(tvb,offset)) != 'e' )
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{
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switch( one_byte )
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{
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/* a integer */
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case 'i':
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offset = dissect_bencoded_int( tvb, pinfo, sub_tree, offset, &result, "Integer" );
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break;
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/* a sub-list */
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case 'l':
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offset = dissect_bencoded_list( tvb, pinfo, sub_tree, offset, "Sub-list" );
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break;
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/* a dictionary */
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case 'd':
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offset = dissect_bencoded_dict( tvb, pinfo, sub_tree, offset, "Sub-dict" );
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break;
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/* a string */
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default:
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offset = dissect_bencoded_string( tvb, pinfo, sub_tree, offset, &result, FALSE, "String" );
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break;
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}
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}
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2012-01-20 03:24:05 +00:00
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offset += 1;
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2011-10-28 14:50:13 +00:00
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return offset;
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}
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/* dissect a bt dht error from tvb, start at offset. it's like "li201e9:error msge" */
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2012-01-20 03:24:05 +00:00
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static int
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2012-06-04 13:21:44 +00:00
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dissect_bt_dht_error(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, guint offset, char **result, const char *label )
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2011-10-28 14:50:13 +00:00
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{
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proto_item *ti;
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proto_tree *sub_tree;
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2012-01-20 03:24:05 +00:00
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char *error_no, *error_msg;
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2011-10-28 14:50:13 +00:00
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2012-01-20 03:24:05 +00:00
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error_no = NULL;
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2011-10-28 14:50:13 +00:00
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error_msg = NULL;
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2012-01-20 03:24:05 +00:00
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ti = proto_tree_add_item( tree, hf_bt_dht_error, tvb, offset, 0, ENC_NA );
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2011-10-28 14:50:13 +00:00
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sub_tree = proto_item_add_subtree( ti, ett_bt_dht_error);
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/* we have confirmed that the first byte is 'l' */
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2012-01-20 03:24:05 +00:00
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offset += 1;
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2011-10-28 14:50:13 +00:00
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/* dissect bt-dht error number and message */
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offset = dissect_bencoded_int( tvb, pinfo, sub_tree, offset, &error_no, "Error ID" );
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offset = dissect_bencoded_string( tvb, pinfo, sub_tree, offset, &error_msg, FALSE, "Error Message" );
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proto_item_set_text( ti, "%s: error %s, %s", label, error_no, error_msg );
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2013-04-20 09:49:00 +00:00
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col_append_fstr( pinfo->cinfo, COL_INFO, "error_no=%s error_msg=%s ", error_no, error_msg );
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2011-10-28 14:50:13 +00:00
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*result = ep_strdup_printf("error %s, %s", error_no, error_msg );
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return offset;
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}
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/* dissect a bt dht values list from tvb, start at offset. it's like "l6:....6:....e" */
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2012-01-20 03:24:05 +00:00
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static int
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2012-06-04 13:21:44 +00:00
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dissect_bt_dht_values(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, guint offset, char **result, const char *label )
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2011-10-28 14:50:13 +00:00
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{
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proto_item *ti;
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proto_tree *sub_tree;
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proto_item *value_ti;
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proto_tree *value_tree;
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2012-01-20 03:24:05 +00:00
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guint peer_index;
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guint string_len;
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2011-10-28 14:50:13 +00:00
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ti = proto_tree_add_item( tree, hf_bt_dht_peers, tvb, offset, 0, ENC_NA );
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sub_tree = proto_item_add_subtree( ti, ett_bt_dht_peers);
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peer_index = 0;
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/* we has confirmed that the first byte is 'l' */
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2012-01-20 03:24:05 +00:00
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offset += 1;
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2011-10-28 14:50:13 +00:00
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/* dissect bt-dht values */
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while( tvb_get_guint8(tvb,offset)!='e' )
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{
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2012-12-05 09:27:58 +00:00
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string_len = bencoded_string_length(tvb, &offset);
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2011-10-28 14:50:13 +00:00
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/* 4 bytes ip, 2 bytes port */
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for( ; string_len>=6; string_len-=6, offset+=6 )
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{
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2012-01-20 03:24:05 +00:00
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peer_index += 1;
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2011-10-28 14:50:13 +00:00
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2013-04-20 09:49:00 +00:00
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value_ti = proto_tree_add_item( sub_tree, hf_bt_dht_peer, tvb, offset, 6, ENC_NA );
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proto_item_append_text(value_ti, " %d", peer_index);
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2011-10-28 14:50:13 +00:00
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value_tree = proto_item_add_subtree( value_ti, ett_bt_dht_peers);
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proto_tree_add_item( value_tree, hf_ip, tvb, offset, 4, ENC_BIG_ENDIAN);
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2013-04-20 09:49:00 +00:00
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proto_item_append_text(value_ti, " (IP/Port: %s", tvb_ip_to_str(tvb, offset));
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2011-10-28 14:50:13 +00:00
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proto_tree_add_item( value_tree, hf_port, tvb, offset+4, 2, ENC_BIG_ENDIAN);
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2013-04-20 09:49:00 +00:00
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proto_item_append_text(value_ti, ":%u)", tvb_get_ntohs( tvb, offset+4 ));
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2011-10-28 14:50:13 +00:00
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}
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/* truncated data */
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if( string_len>0 )
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{
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proto_tree_add_item( tree, hf_truncated_data, tvb, offset, string_len, ENC_NA );
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offset += string_len;
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}
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}
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proto_item_set_text( ti, "%s: %d peers", label, peer_index );
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2013-04-20 09:49:00 +00:00
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col_append_fstr( pinfo->cinfo, COL_INFO, "reply=%d peers ", peer_index );
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2011-10-28 14:50:13 +00:00
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*result = ep_strdup_printf("%d peers", peer_index);
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return offset;
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}
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2012-01-20 03:24:05 +00:00
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static int
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2012-12-26 05:57:06 +00:00
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dissect_bt_dht_nodes(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, guint offset, char **result, const char *label )
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2011-10-28 14:50:13 +00:00
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{
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proto_item *ti;
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proto_tree *sub_tree;
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proto_item *node_ti;
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proto_tree *node_tree;
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|
|
2012-01-20 03:24:05 +00:00
|
|
|
guint node_index;
|
|
|
|
guint string_len;
|
2011-10-28 14:50:13 +00:00
|
|
|
|
2012-12-05 09:27:58 +00:00
|
|
|
string_len = bencoded_string_length(tvb, &offset);
|
|
|
|
|
|
|
|
ti = proto_tree_add_item( tree, hf_bt_dht_nodes, tvb, offset, string_len, ENC_NA );
|
2011-10-28 14:50:13 +00:00
|
|
|
sub_tree = proto_item_add_subtree( ti, ett_bt_dht_nodes);
|
|
|
|
node_index = 0;
|
|
|
|
|
|
|
|
/* 20 bytes id, 4 bytes ip, 2 bytes port */
|
|
|
|
for( ; string_len>=26; string_len-=26, offset+=26 )
|
|
|
|
{
|
2012-01-20 03:24:05 +00:00
|
|
|
node_index += 1;
|
2011-10-28 14:50:13 +00:00
|
|
|
|
|
|
|
|
2013-04-20 09:49:00 +00:00
|
|
|
node_ti = proto_tree_add_item( sub_tree, hf_bt_dht_node, tvb, offset, 26, ENC_NA);
|
|
|
|
proto_item_append_text(node_ti, " %d", node_index);
|
2011-10-28 14:50:13 +00:00
|
|
|
node_tree = proto_item_add_subtree( node_ti, ett_bt_dht_peers);
|
|
|
|
|
|
|
|
proto_tree_add_item( node_tree, hf_bt_dht_id, tvb, offset, 20, ENC_NA);
|
2013-04-20 09:49:00 +00:00
|
|
|
proto_item_append_text(node_ti, " (id: %s", tvb_bytes_to_str(tvb, offset, 20));
|
2011-10-28 14:50:13 +00:00
|
|
|
proto_tree_add_item( node_tree, hf_ip, tvb, offset+20, 4, ENC_BIG_ENDIAN);
|
2013-04-20 09:49:00 +00:00
|
|
|
proto_item_append_text(node_ti, ", IP/Port: %s", tvb_ip_to_str(tvb, offset+20));
|
2011-10-28 14:50:13 +00:00
|
|
|
proto_tree_add_item( node_tree, hf_port, tvb, offset+24, 2, ENC_BIG_ENDIAN);
|
2013-04-20 09:49:00 +00:00
|
|
|
proto_item_append_text(node_ti, ":%u)", tvb_get_ntohs( tvb, offset+24 ));
|
2011-10-28 14:50:13 +00:00
|
|
|
}
|
|
|
|
if( string_len>0 )
|
|
|
|
{
|
|
|
|
proto_tree_add_item( tree, hf_truncated_data, tvb, offset, string_len, ENC_NA );
|
|
|
|
offset += string_len;
|
|
|
|
}
|
|
|
|
proto_item_set_text( ti, "%s: %d nodes", label, node_index );
|
2013-04-20 09:49:00 +00:00
|
|
|
col_append_fstr( pinfo->cinfo, COL_INFO, "reply=%d nodes ", node_index );
|
2011-10-28 14:50:13 +00:00
|
|
|
*result = ep_strdup_printf("%d", node_index);
|
|
|
|
|
|
|
|
return offset;
|
|
|
|
}
|
|
|
|
|
2012-01-20 03:24:05 +00:00
|
|
|
static int
|
|
|
|
dissect_bencoded_dict_entry(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, guint offset )
|
2011-10-28 14:50:13 +00:00
|
|
|
{
|
|
|
|
proto_item *ti;
|
|
|
|
proto_tree *sub_tree;
|
2012-01-20 03:24:05 +00:00
|
|
|
gboolean tohex;
|
|
|
|
char *key, *val;
|
|
|
|
guint orig_offset = offset;
|
2011-10-28 14:50:13 +00:00
|
|
|
|
|
|
|
key = NULL;
|
|
|
|
val = NULL;
|
|
|
|
|
2012-01-20 03:24:05 +00:00
|
|
|
ti = proto_tree_add_item( tree, hf_bencoded_dict_entry, tvb, offset, 0, ENC_NA );
|
2011-10-28 14:50:13 +00:00
|
|
|
sub_tree = proto_item_add_subtree( ti, ett_bencoded_dict_entry);
|
|
|
|
|
|
|
|
/* dissect the key, it must be a string */
|
2012-01-20 03:24:05 +00:00
|
|
|
offset = dissect_bencoded_string( tvb, pinfo, sub_tree, offset, &key, FALSE, "Key" );
|
2011-10-28 14:50:13 +00:00
|
|
|
|
2012-01-20 03:24:05 +00:00
|
|
|
/* If it is a dict, then just do recursion */
|
2011-10-28 14:50:13 +00:00
|
|
|
switch( tvb_get_guint8(tvb,offset) )
|
|
|
|
{
|
|
|
|
case 'd':
|
|
|
|
offset = dissect_bencoded_dict( tvb, pinfo, sub_tree, offset, "Value" );
|
2012-01-20 03:24:05 +00:00
|
|
|
val = (char*)dict_str;
|
2011-10-28 14:50:13 +00:00
|
|
|
break;
|
|
|
|
case 'l':
|
|
|
|
if( strcmp(key,"e")==0 )
|
|
|
|
offset = dissect_bt_dht_error( tvb, pinfo, sub_tree, offset, &val, "Value" );
|
|
|
|
else if( strcmp(key,"values")==0 )
|
|
|
|
offset = dissect_bt_dht_values( tvb, pinfo, sub_tree, offset, &val, "Value" );
|
|
|
|
/* other unfamiliar lists */
|
|
|
|
else
|
|
|
|
{
|
|
|
|
offset = dissect_bencoded_list( tvb, pinfo, sub_tree, offset, "Value" );
|
|
|
|
val = (char*)list_str;
|
|
|
|
}
|
|
|
|
break;
|
|
|
|
case 'i':
|
|
|
|
offset = dissect_bencoded_int( tvb, pinfo, sub_tree, offset, &val, "Value" );
|
|
|
|
break;
|
|
|
|
/* it's a string */
|
|
|
|
default:
|
|
|
|
/* special process */
|
2012-12-05 09:27:58 +00:00
|
|
|
if( strcmp(key,"nodes")==0 )
|
|
|
|
{
|
2011-10-28 14:50:13 +00:00
|
|
|
offset = dissect_bt_dht_nodes( tvb, pinfo, sub_tree, offset, &val, "Value" );
|
2012-12-05 09:27:58 +00:00
|
|
|
}
|
|
|
|
else if( strcmp(key,"ip")==0 )
|
|
|
|
{
|
|
|
|
/*
|
|
|
|
* Not found in BEP 0005 but explained by
|
|
|
|
* http://www.rasterbar.com/products/libtorrent/dht_sec.html
|
|
|
|
*/
|
|
|
|
|
|
|
|
int len, old_offset;
|
|
|
|
old_offset = offset;
|
|
|
|
len = bencoded_string_length(tvb, &offset);
|
|
|
|
|
|
|
|
if(len == 4) {
|
2013-04-20 09:49:00 +00:00
|
|
|
proto_tree_add_item(sub_tree, hf_ip, tvb, offset, len, ENC_BIG_ENDIAN);
|
|
|
|
val = (char*)tvb_ip_to_str(tvb, offset);
|
2012-12-05 09:27:58 +00:00
|
|
|
offset += len;
|
|
|
|
}
|
|
|
|
else {
|
|
|
|
offset = dissect_bencoded_string( tvb, pinfo, sub_tree, old_offset, &val, TRUE, "Value" );
|
|
|
|
}
|
|
|
|
}
|
2011-10-28 14:50:13 +00:00
|
|
|
else
|
|
|
|
{
|
2012-12-05 09:27:58 +00:00
|
|
|
/* some need to return hex string */
|
2011-10-28 14:50:13 +00:00
|
|
|
tohex = strcmp(key,"id")==0 || strcmp(key,"target")==0
|
|
|
|
|| strcmp(key,"info_hash")==0 || strcmp(key,"t")==0
|
2012-12-05 09:27:58 +00:00
|
|
|
|| strcmp(key,"v")==0 || strcmp(key,"token")==0;
|
2011-10-28 14:50:13 +00:00
|
|
|
offset = dissect_bencoded_string( tvb, pinfo, sub_tree, offset, &val, tohex, "Value" );
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
if( strlen(key)==1 )
|
2012-08-10 22:55:02 +00:00
|
|
|
key = (char*)val_to_str_const( key[0], short_key_name_value_string, key );
|
2011-10-28 14:50:13 +00:00
|
|
|
if( strlen(val)==1 )
|
2012-08-10 22:55:02 +00:00
|
|
|
val = (char*)val_to_str_const( val[0], short_val_name_value_string, val );
|
2011-10-28 14:50:13 +00:00
|
|
|
|
|
|
|
proto_item_set_text( ti, "%s: %s", key, val );
|
2012-01-20 03:24:05 +00:00
|
|
|
proto_item_set_len( ti, offset-orig_offset );
|
2011-10-28 14:50:13 +00:00
|
|
|
|
|
|
|
if( strcmp(key,"message_type")==0 || strcmp(key,"request_type")==0 )
|
2013-04-20 09:49:00 +00:00
|
|
|
col_append_fstr(pinfo->cinfo, COL_INFO, "%s=%s ", key, val);
|
2011-10-28 14:50:13 +00:00
|
|
|
|
|
|
|
return offset;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* dict = d...e */
|
2012-01-20 03:24:05 +00:00
|
|
|
static int
|
2012-12-26 05:57:06 +00:00
|
|
|
dissect_bencoded_dict(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, guint offset, const char *label )
|
2011-10-28 14:50:13 +00:00
|
|
|
{
|
|
|
|
proto_item *ti;
|
|
|
|
proto_tree *sub_tree;
|
2012-01-20 03:24:05 +00:00
|
|
|
guint orig_offset = offset;
|
2011-10-28 14:50:13 +00:00
|
|
|
|
2012-12-05 09:27:58 +00:00
|
|
|
if(offset == 0)
|
|
|
|
{
|
|
|
|
ti = proto_tree_add_item(tree, proto_bt_dht, tvb, 0, -1, ENC_NA);
|
|
|
|
sub_tree = proto_item_add_subtree(ti, ett_bt_dht);
|
|
|
|
}
|
|
|
|
else
|
|
|
|
{
|
2013-04-20 09:49:00 +00:00
|
|
|
ti = proto_tree_add_none_format( tree, hf_bencoded_dict, tvb, offset, -1, "%s: Dictionary...", label );
|
2012-12-05 09:27:58 +00:00
|
|
|
sub_tree = proto_item_add_subtree( ti, ett_bencoded_dict);
|
|
|
|
}
|
2011-10-28 14:50:13 +00:00
|
|
|
|
|
|
|
/* skip the first char('d') */
|
2012-01-20 03:24:05 +00:00
|
|
|
offset += 1;
|
2011-10-28 14:50:13 +00:00
|
|
|
|
|
|
|
while( tvb_get_guint8(tvb,offset)!='e' )
|
|
|
|
offset = dissect_bencoded_dict_entry( tvb, pinfo, sub_tree, offset );
|
|
|
|
|
2012-01-20 03:24:05 +00:00
|
|
|
offset += 1;
|
|
|
|
proto_item_set_len( ti, offset-orig_offset );
|
|
|
|
|
2011-10-28 14:50:13 +00:00
|
|
|
return offset;
|
|
|
|
}
|
|
|
|
|
2012-01-20 03:24:05 +00:00
|
|
|
static int
|
2012-09-10 21:40:21 +00:00
|
|
|
dissect_bt_dht(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data _U_)
|
2011-10-28 14:50:13 +00:00
|
|
|
{
|
|
|
|
col_set_str(pinfo->cinfo, COL_PROTOCOL, "BT-DHT");
|
|
|
|
col_clear(pinfo->cinfo, COL_INFO);
|
2012-01-20 03:24:05 +00:00
|
|
|
|
2012-12-05 09:27:58 +00:00
|
|
|
return dissect_bencoded_dict(tvb, pinfo, tree, 0, "BitTorrent DHT Protocol");
|
2011-10-28 14:50:13 +00:00
|
|
|
}
|
|
|
|
|
2012-01-20 03:24:05 +00:00
|
|
|
static
|
|
|
|
gboolean dissect_bt_dht_heur (tvbuff_t *tvb, packet_info *pinfo,
|
2012-09-10 21:40:21 +00:00
|
|
|
proto_tree *tree, void *data _U_)
|
2011-10-28 14:50:13 +00:00
|
|
|
{
|
|
|
|
/* try dissecting */
|
2012-12-05 09:27:58 +00:00
|
|
|
/* Assume dictionary (d) is followed by a one char long (1:) key string. */
|
|
|
|
if(tvb_memeql(tvb, 0, "d1:", 3) == 0)
|
2011-10-28 14:50:13 +00:00
|
|
|
{
|
2012-12-05 09:27:58 +00:00
|
|
|
int i;
|
|
|
|
guint8 key = tvb_get_guint8(tvb, 3);
|
2011-10-28 14:50:13 +00:00
|
|
|
|
2012-12-05 09:27:58 +00:00
|
|
|
/* Iterate through possible keys to improve heuristics. */
|
|
|
|
for(i=0; short_key_name_value_string[i].value != 0; i++)
|
|
|
|
{
|
|
|
|
if(short_key_name_value_string[i].value == key)
|
|
|
|
{
|
|
|
|
conversation_t *conversation;
|
|
|
|
|
|
|
|
conversation = find_or_create_conversation(pinfo);
|
|
|
|
conversation_set_dissector(conversation, bt_dht_handle);
|
2012-01-20 03:24:05 +00:00
|
|
|
|
2012-12-05 09:27:58 +00:00
|
|
|
dissect_bt_dht(tvb, pinfo, tree, NULL);
|
|
|
|
return TRUE;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
return FALSE;
|
2011-10-28 14:50:13 +00:00
|
|
|
}
|
|
|
|
|
2012-01-20 03:24:05 +00:00
|
|
|
void proto_reg_handoff_bt_dht(void);
|
|
|
|
|
|
|
|
void
|
|
|
|
proto_register_bt_dht(void)
|
2011-10-28 14:50:13 +00:00
|
|
|
{
|
|
|
|
static hf_register_info hf[] = {
|
|
|
|
{ &hf_bencoded_string,
|
2013-04-20 09:49:00 +00:00
|
|
|
{ "String", "bt-dht.bencoded.string",
|
2011-10-28 14:50:13 +00:00
|
|
|
FT_STRING, BASE_NONE, NULL, 0x0, NULL, HFILL }
|
|
|
|
},
|
|
|
|
{ &hf_bencoded_list,
|
2013-04-20 09:49:00 +00:00
|
|
|
{ "List", "bt-dht.bencoded.list",
|
2011-10-28 14:50:13 +00:00
|
|
|
FT_NONE, BASE_NONE, NULL, 0x0, NULL, HFILL }
|
|
|
|
},
|
|
|
|
{ &hf_bencoded_int,
|
2013-04-20 09:49:00 +00:00
|
|
|
{ "Int", "bt-dht.bencoded.int",
|
2011-10-28 14:50:13 +00:00
|
|
|
FT_STRING, BASE_NONE, NULL, 0x0, NULL, HFILL }
|
|
|
|
},
|
|
|
|
{ &hf_bencoded_dict,
|
2013-04-20 09:49:00 +00:00
|
|
|
{ "Dictionary", "bt-dht.bencoded.dict",
|
2011-10-28 14:50:13 +00:00
|
|
|
FT_NONE, BASE_NONE, NULL, 0x0, NULL, HFILL }
|
|
|
|
},
|
|
|
|
{ &hf_bencoded_dict_entry,
|
2013-04-20 09:49:00 +00:00
|
|
|
{ "Dictionary Entry", "bt-dht.bencoded.dict_entry",
|
2011-10-28 14:50:13 +00:00
|
|
|
FT_NONE, BASE_NONE, NULL, 0x0, NULL, HFILL }
|
|
|
|
},
|
|
|
|
{ &hf_bt_dht_error,
|
|
|
|
{ "Error", "bt-dht.error",
|
|
|
|
FT_NONE, BASE_NONE, NULL, 0x0, NULL, HFILL }
|
|
|
|
},
|
|
|
|
{ &hf_bt_dht_peer,
|
2013-04-20 09:49:00 +00:00
|
|
|
{ "Peer", "bt-dht.peer",
|
2011-10-28 14:50:13 +00:00
|
|
|
FT_NONE, BASE_NONE, NULL, 0x0, NULL, HFILL }
|
|
|
|
},
|
|
|
|
{ &hf_bt_dht_peers,
|
|
|
|
{ "Peers", "bt-dht.peers",
|
|
|
|
FT_NONE, BASE_NONE, NULL, 0x0, NULL, HFILL }
|
|
|
|
},
|
|
|
|
{ &hf_bt_dht_node,
|
|
|
|
{ "Node", "bt-dht.node",
|
|
|
|
FT_NONE, BASE_NONE, NULL, 0x0, NULL, HFILL }
|
|
|
|
},
|
|
|
|
{ &hf_bt_dht_nodes,
|
|
|
|
{ "Nodes", "bt-dht.nodes",
|
|
|
|
FT_NONE, BASE_NONE, NULL, 0x0, NULL, HFILL }
|
|
|
|
},
|
|
|
|
{ &hf_bt_dht_id,
|
2013-04-20 09:49:00 +00:00
|
|
|
{ "ID", "bt-dht.id",
|
2011-10-28 14:50:13 +00:00
|
|
|
FT_BYTES, BASE_NONE, NULL, 0x0, NULL, HFILL }
|
|
|
|
},
|
|
|
|
{ &hf_ip,
|
2013-04-20 09:49:00 +00:00
|
|
|
{ "IP", "bt-dht.ip",
|
2011-10-28 14:50:13 +00:00
|
|
|
FT_IPv4, BASE_NONE, NULL, 0x0, NULL, HFILL }
|
|
|
|
},
|
|
|
|
{ &hf_port,
|
2013-04-20 09:49:00 +00:00
|
|
|
{ "Port", "bt-dht.port",
|
2011-10-28 14:50:13 +00:00
|
|
|
FT_UINT16, BASE_DEC, NULL, 0x0, NULL, HFILL }
|
|
|
|
},
|
|
|
|
{ &hf_truncated_data,
|
2013-04-20 09:49:00 +00:00
|
|
|
{ "Truncated data", "bt-dht.truncated_data",
|
2011-10-28 14:50:13 +00:00
|
|
|
FT_BYTES, BASE_NONE, NULL, 0x0, NULL, HFILL }
|
|
|
|
}
|
|
|
|
};
|
|
|
|
|
|
|
|
/* Setup protocol subtree array */
|
|
|
|
static gint *ett[] = {
|
|
|
|
&ett_bt_dht,
|
|
|
|
&ett_bencoded_list,
|
|
|
|
&ett_bencoded_dict,
|
|
|
|
&ett_bt_dht_error,
|
|
|
|
&ett_bt_dht_peers,
|
|
|
|
&ett_bt_dht_nodes,
|
|
|
|
&ett_bencoded_dict_entry
|
|
|
|
};
|
|
|
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2012-01-20 03:24:05 +00:00
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module_t *bt_dht_module;
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2011-10-28 14:50:13 +00:00
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proto_bt_dht = proto_register_protocol (
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2012-12-05 09:27:58 +00:00
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"BitTorrent DHT Protocol", /* name */
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2011-11-15 19:00:08 +00:00
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"BT-DHT", /* short name */
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"bt-dht" /* abbrev */
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2011-10-28 14:50:13 +00:00
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);
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2012-01-20 03:24:05 +00:00
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bt_dht_module = prefs_register_protocol(proto_bt_dht, proto_reg_handoff_bt_dht);
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2012-12-05 09:27:58 +00:00
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prefs_register_bool_preference(bt_dht_module, "enable", "Enable BT-DHT heuristic dissection",
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2012-01-20 03:24:05 +00:00
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"Enable BT-DHT heuristic dissection (default is disabled)",
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&bt_dht_enable_heuristic_dissection);
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2011-10-28 14:50:13 +00:00
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proto_register_field_array(proto_bt_dht, hf, array_length(hf));
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proto_register_subtree_array(ett, array_length(ett));
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}
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2011-11-15 19:00:08 +00:00
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2012-01-20 03:24:05 +00:00
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void
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proto_reg_handoff_bt_dht(void)
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2011-11-15 19:00:08 +00:00
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{
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2012-01-20 03:24:05 +00:00
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static gboolean prefs_initialized = FALSE;
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/* "Decode As" is always available;
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* Heuristic dissection in disabled by default since the heuristic is quite weak.
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2012-12-05 09:27:58 +00:00
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* XXX - Still too weak?
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2012-01-20 03:24:05 +00:00
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*/
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if (!prefs_initialized) {
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heur_dissector_add("udp", dissect_bt_dht_heur, proto_bt_dht);
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bt_dht_handle = new_create_dissector_handle(dissect_bt_dht, proto_bt_dht);
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dissector_add_handle("udp.port", bt_dht_handle); /* for "decode_as" */
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prefs_initialized = TRUE;
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}
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heur_dissector_set_enabled("udp", dissect_bt_dht_heur, proto_bt_dht, bt_dht_enable_heuristic_dissection);
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2011-11-15 19:00:08 +00:00
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}
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2012-01-20 03:24:05 +00:00
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/*
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* Editor modelines
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*
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* Local Variables:
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* c-basic-offset: 2
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* tab-width: 8
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* indent-tabs-mode: nil
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* End:
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*
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* ex: set shiftwidth=2 tabstop=8 expandtab:
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* :indentSize=2:tabSize=8:noTabs=true:
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*/
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