/* packet-bittorrent.c * Routines for bittorrent packet dissection * Copyright (C) 2004 Jelmer Vernooij * * $Id$ * * Wireshark - Network traffic analyzer * By Gerald Combs * Copyright 1998 Gerald Combs * * Copied from packet-pop.c * * 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ #ifdef HAVE_CONFIG_H # include "config.h" #endif #include #include #include #include #include #include #include #include #include "packet-tcp.h" /* * See * * http://bittorrent.com/protocol.html * http://wiki.theory.org/BitTorrentSpecification * http://bitconjurer.org/BitTorrent/protocol.html */ #define BITTORRENT_MESSAGE_CHOKE 0 #define BITTORRENT_MESSAGE_UNCHOKE 1 #define BITTORRENT_MESSAGE_INTERESTED 2 #define BITTORRENT_MESSAGE_NOT_INTERESTED 3 #define BITTORRENT_MESSAGE_HAVE 4 #define BITTORRENT_MESSAGE_BITFIELD 5 #define BITTORRENT_MESSAGE_REQUEST 6 #define BITTORRENT_MESSAGE_PIECE 7 #define BITTORRENT_MESSAGE_CANCEL 8 #define BITTORRENT_HEADER_LENGTH 4 /* * Azureus messages are specified by name so these are made up numbers * for internal identification only. * * Standard BT message types are a single byte, so these won't clash */ #define AZUREUS_MESSAGE_HANDSHAKE 256 #define AZUREUS_MESSAGE_KEEP_ALIVE 257 #define AZUREUS_MESSAGE_BT_HANDSHAKE 258 #define AZUREUS_MESSAGE_PEER_EXCHANGE 259 #define AZUREUS_MESSAGE_JPC_HELLO 260 #define AZUREUS_MESSAGE_JPC_REPLY 261 static const value_string bittorrent_messages[] = { { BITTORRENT_MESSAGE_CHOKE, "Choke" }, { BITTORRENT_MESSAGE_UNCHOKE, "Unchoke" }, { BITTORRENT_MESSAGE_INTERESTED, "Interested" }, { BITTORRENT_MESSAGE_NOT_INTERESTED, "Not Interested" }, { BITTORRENT_MESSAGE_HAVE, "Have" }, { BITTORRENT_MESSAGE_BITFIELD, "Bitfield" }, { BITTORRENT_MESSAGE_REQUEST, "Request" }, { BITTORRENT_MESSAGE_PIECE, "Piece" }, { BITTORRENT_MESSAGE_CANCEL, "Cancel" }, { AZUREUS_MESSAGE_KEEP_ALIVE, "Keepalive" }, { AZUREUS_MESSAGE_HANDSHAKE, "Azureus Handshake" }, { AZUREUS_MESSAGE_BT_HANDSHAKE, "Azureus BitTorrent Handshake" }, { AZUREUS_MESSAGE_PEER_EXCHANGE, "Azureus Peer Exchange" }, { AZUREUS_MESSAGE_JPC_HELLO, "Azureus PeerCache Hello" }, { AZUREUS_MESSAGE_JPC_REPLY, "Azureus PeerCache Reply" }, { 0, NULL } }; static const value_string azureus_priorities[] = { { 0, "Low" }, { 1, "Normal" }, { 2, "High" }, { 0, NULL } }; struct amp_message { char *name; guint32 value; }; static const struct amp_message amp_messages[] = { { "BT_KEEP_ALIVE", AZUREUS_MESSAGE_KEEP_ALIVE }, { "BT_CHOKE", BITTORRENT_MESSAGE_CHOKE }, { "BT_UNCHOKE", BITTORRENT_MESSAGE_UNCHOKE }, { "BT_INTERESTED", BITTORRENT_MESSAGE_INTERESTED }, { "BT_UNINTERESTED", BITTORRENT_MESSAGE_NOT_INTERESTED }, { "BT_HAVE", BITTORRENT_MESSAGE_HAVE }, { "BT_BITFIELD", BITTORRENT_MESSAGE_BITFIELD }, { "BT_REQUEST", BITTORRENT_MESSAGE_REQUEST }, { "BT_PIECE", BITTORRENT_MESSAGE_PIECE }, { "BT_CANCEL", BITTORRENT_MESSAGE_CANCEL }, { "AZ_HANDSHAKE", AZUREUS_MESSAGE_HANDSHAKE }, { "BT_HANDSHAKE", AZUREUS_MESSAGE_BT_HANDSHAKE }, { "AZ_PEER_EXCHANGE", AZUREUS_MESSAGE_PEER_EXCHANGE }, { "JPC_HELLO", AZUREUS_MESSAGE_JPC_HELLO }, { "JPC_REPLY", AZUREUS_MESSAGE_JPC_REPLY }, { NULL, 0 } }; static dissector_handle_t dissector_handle; static int proto_bittorrent = -1; static gint hf_bittorrent_field_length = -1; static gint hf_bittorrent_prot_name_len = -1; static gint hf_bittorrent_prot_name = -1; static gint hf_bittorrent_reserved = -1; static gint hf_bittorrent_sha1_hash = -1; static gint hf_bittorrent_peer_id = -1; static gint hf_bittorrent_msg = -1; static gint hf_bittorrent_msg_len = -1; static gint hf_bittorrent_msg_type = -1; static gint hf_azureus_msg = -1; static gint hf_azureus_msg_type_len = -1; static gint hf_azureus_msg_type = -1; static gint hf_azureus_msg_prio = -1; static gint hf_bittorrent_bitfield_data = -1; static gint hf_bittorrent_piece_index = -1; static gint hf_bittorrent_piece_begin = -1; static gint hf_bittorrent_piece_length = -1; static gint hf_bittorrent_piece_data = -1; static gint hf_bittorrent_bstr_length = -1; static gint hf_bittorrent_bstr = -1; static gint hf_bittorrent_bint = -1; static gint hf_bittorrent_bdict = -1; static gint hf_bittorrent_bdict_entry = -1; static gint hf_bittorrent_blist = -1; static gint hf_azureus_jpc_addrlen = -1; static gint hf_azureus_jpc_addr = -1; static gint hf_azureus_jpc_port = -1; static gint hf_azureus_jpc_session = -1; static gint ett_bittorrent = -1; static gint ett_bittorrent_msg = -1; static gint ett_peer_id = -1; static gint ett_bittorrent_bdict = -1; static gint ett_bittorrent_bdict_entry = -1; static gint ett_bittorrent_blist = -1; static gboolean bittorrent_desegment = TRUE; static gboolean decode_client_information = FALSE; struct client_information { char id[4]; char *name; }; static struct client_information peer_id[] = { {"-AZ", "Azureus"}, {"-BB", "BitBuddy"}, {"-CT", "CTorrent"}, {"-MT", "MoonlightTorrent"}, {"-LT", "libtorrent"}, {"-BX", "Bittorrent X"}, {"-TS", "Torrentstorm"}, {"-TN", "TorrnetDotNET"}, {"-SS", "SwarmScope"}, {"-XT", "XanTorrent"}, {"-BS", "BTSlave"}, {"-ZT", "ZipTorrent"}, {"S", "Shadow's client"}, {"U", "UPnP NAT Bit Torrent"}, {"T", "BitTornado"}, {"A", "ABC"}, {"", NULL} }; static guint get_bittorrent_pdu_length(tvbuff_t *tvb, int offset) { guint8 type; guint32 length; if (tvb_get_guint8(tvb, offset) == 19 && tvb_memeql(tvb, offset + 1, "BitTorrent protocol", 19) == 0) { /* Return the length of a Handshake message */ return 1 + /* pstrlen */ 19 + /* pstr */ 8 + /* reserved */ 20 + /* SHA1 hash of the info key */ 20; /* peer id */ } else { /* Try to validate the length of the message indicated by the header. */ length = tvb_get_ntohl(tvb, offset); if(length == 0) { /* keep-alive - no message ID */ return BITTORRENT_HEADER_LENGTH; } /* Do some sanity checking of the message, if we have the ID byte */ if(tvb_offset_exists(tvb, offset + BITTORRENT_HEADER_LENGTH)) { type = tvb_get_guint8(tvb, offset + BITTORRENT_HEADER_LENGTH); if(type <= BITTORRENT_MESSAGE_CANCEL && length<0x1000000) { /* This seems to be a valid BitTorrent header with a known type identifier */ return BITTORRENT_HEADER_LENGTH + length; } else { /* The type is not known, so this message cannot be decoded properly by this dissector. We assume it's continuation data from the middle of a message, and just return the remaining length in the tvbuff so the rest of the tvbuff is displayed as continuation data. */ return tvb_length_remaining(tvb, offset); } } else { /* We don't have the type field, so we can't determine whether this is a valid message. For now, we assume it's continuation data from the middle of a message, and just return the remaining length in the tvbuff so the rest of the tvbuff is displayed as continuation data. */ return tvb_length_remaining(tvb, offset); } } } static int dissect_bencoding_str(tvbuff_t *tvb, packet_info *pinfo _U_, int offset, int length, proto_tree *tree, proto_item *ti, int treeadd) { guint8 ch; int stringlen = 0, nextstringlen; int used; int izero = 0; if (length<2) { if (tree) { proto_tree_add_text(tree, tvb, offset, length, "Decode Aborted: Invalid String"); } return -1; } used = 0; while (length>=1) { ch = tvb_get_guint8(tvb, offset+used); length--; used++; if (ch==':' && used>1) { if (stringlen>length || stringlen<0) { if (tree) { proto_tree_add_text(tree, tvb, offset, length, "Decode Aborted: Invalid String Length"); } return -1; } if (tree) { proto_tree_add_uint(tree, hf_bittorrent_bstr_length, tvb, offset, used, stringlen); proto_tree_add_item(tree, hf_bittorrent_bstr, tvb, offset+used, stringlen, FALSE); if (treeadd==1) { proto_item_append_text(ti, " Key: %s", format_text(ep_tvb_memdup(tvb, offset+used, stringlen), stringlen)); } if (treeadd==2) { proto_item_append_text(ti, " Value: %s", format_text(ep_tvb_memdup(tvb, offset+used, stringlen), stringlen)); } } return used+stringlen; } if (!izero && ch>='0' && ch<='9') { if (ch=='0' && used==1) { izero = 1; } nextstringlen = (stringlen * 10) + (ch - '0'); if (nextstringlen>=stringlen) { stringlen = nextstringlen; continue; } } if (tree) { proto_tree_add_text(tree, tvb, offset, length, "Decode Aborted: Invalid String"); } return -1; } if (tree) { proto_tree_add_text(tree, tvb, offset, length, "Truncated Data"); } return -1; } static int dissect_bencoding_int(tvbuff_t *tvb, packet_info *pinfo _U_, int offset, int length, proto_tree *tree, proto_item *ti, int treeadd) { gint32 ival=0; int neg = 0; int izero = 0; int used; guint8 ch; if (length<3) { if (tree) { proto_tree_add_text(tree, tvb, offset, length, "Decode Aborted: Invalid Integer"); } return -1; } length--; used = 1; while (length>=1) { ch = tvb_get_guint8(tvb, offset+used); length--; used++; switch (ch) { case 'e': if (tree) { if (neg) ival = -ival; proto_tree_add_int(tree, hf_bittorrent_bint, tvb, offset, used, ival); if (treeadd==2) { proto_item_append_text(ti, " Value: %d", ival); } } return used; case '-': if (used==2) { neg = 1; break; } /* Fall through */ default: if (!(ch=='0' && used==3 && neg)) { /* -0 is invalid */ if (ch=='0' && used==2) { /* as is 0[0-9]+ */ izero = 1; break; } if (!izero && ch>='0' && ch<='9') { ival = (ival * 10) + (ch - '0'); break; } } if (tree) { proto_tree_add_text(tree, tvb, offset, length, "Decode Aborted: Invalid Integer"); } return -1; } } if (tree) { proto_tree_add_text(tree, tvb, offset, length, "Truncated Data"); } return -1; } static int dissect_bencoding_rec(tvbuff_t *tvb, packet_info *pinfo _U_, int offset, int length, proto_tree *tree, int level, proto_item *treei, int treeadd) { guint8 op; int oplen = 0, op1len, op2len; int used; proto_item *ti = NULL, *td = NULL; proto_tree *itree = NULL, *dtree = NULL; if (level>10) { proto_tree_add_text(tree, tvb, offset, -1, "Decode Aborted: Nested Too Deep"); return -1; } if (length<1) { proto_tree_add_text(tree, tvb, offset, -1, "Truncated Data"); return length; } op = tvb_get_guint8(tvb, offset); if (tree) { oplen = dissect_bencoding_rec(tvb, pinfo, offset, length, NULL, level, NULL, 0); if (oplen<0) oplen = length; } switch (op) { case 'd': if (tree) { td = proto_tree_add_item(tree, hf_bittorrent_bdict, tvb, offset, oplen, FALSE); dtree = proto_item_add_subtree(td, ett_bittorrent_bdict); } used = 1; length--; while (length>=1) { op = tvb_get_guint8(tvb, offset+used); if (op=='e') { return used+1; } op1len = dissect_bencoding_str(tvb, pinfo, offset+used, length, NULL, NULL, 0); if (op1len<0) { if (dtree) { proto_tree_add_text(dtree, tvb, offset+used, -1, "Decode Aborted: Invalid Dictionary Key"); } return op1len; } op2len = -1; if (length-op1len>2) op2len = dissect_bencoding_rec(tvb, pinfo, offset+used+op1len, length-op1len, NULL, level+1, NULL, 0); if (op2len<0) { if (dtree) { proto_tree_add_text(dtree, tvb, offset+used+op1len, -1, "Decode Aborted: Invalid Dictionary Value"); } return op2len; } if (dtree) { ti = proto_tree_add_item(dtree, hf_bittorrent_bdict_entry, tvb, offset+used, op1len+op2len, FALSE); itree = proto_item_add_subtree(ti, ett_bittorrent_bdict_entry); dissect_bencoding_str(tvb, pinfo, offset+used, length, itree, ti, 1); dissect_bencoding_rec(tvb, pinfo, offset+used+op1len, length-op1len, itree, level+1, ti, 2); } used += op1len+op2len; length -= op1len+op2len; } if (dtree) { proto_tree_add_text(dtree, tvb, offset+used, -1, "Truncated Data"); } return -1; case 'l': if (tree) { ti = proto_tree_add_item(tree, hf_bittorrent_blist, tvb, offset, oplen, FALSE); itree = proto_item_add_subtree(ti, ett_bittorrent_blist); } used = 1; length--; while (length>=1) { op = tvb_get_guint8(tvb, offset+used); if (op=='e') { return used+1; } oplen = dissect_bencoding_rec(tvb, pinfo, offset+used, length, itree, level+1, ti, 0); if (oplen<1) return oplen; used += oplen; length -= oplen; } if (itree) { proto_tree_add_text(itree, tvb, offset+used, -1, "Truncated Data"); } return -1; case 'i': return dissect_bencoding_int(tvb, pinfo, offset, length, tree, treei, treeadd); default: if (op>='1' && op<='9') { return dissect_bencoding_str(tvb, pinfo, offset, length, tree, treei, treeadd); } if (tree) { proto_tree_add_text(tree, tvb, offset, -1, "Decode Aborted: Invalid Bencoding"); } return -1; } if (tree) { proto_tree_add_text(tree, tvb, offset, -1, "Decode Aborted: Internal Error"); } return -1; } static void dissect_bencoding(tvbuff_t *tvb, packet_info *pinfo _U_, int offset, int length, proto_tree *tree) { dissect_bencoding_rec(tvb, pinfo, offset, length, tree, 0, NULL, 0); } static void dissect_bittorrent_message (tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree) { int offset = 0; int i; int doffset = BITTORRENT_HEADER_LENGTH; int isamp = 0; proto_tree *mtree; guint16 type = 0; guint32 typelen = 0; guint8 prio = 0; guint32 length; const char *msgtype = NULL; proto_item *ti; guint32 piece_index, piece_begin, piece_length; guint32 stringlen; if (tvb_bytes_exist(tvb, offset + BITTORRENT_HEADER_LENGTH, 1)) { /* Check for data from the middle of a message. */ length = tvb_get_ntohl(tvb, offset); type = tvb_get_guint8(tvb, offset + BITTORRENT_HEADER_LENGTH); if (type==BITTORRENT_MESSAGE_CHOKE && length>4) { /* * Choke messages have no payload, so this is likely an Azureus * Messaging Protocol packet */ if (!tvb_bytes_exist(tvb, offset + BITTORRENT_HEADER_LENGTH, 4)) return; typelen = tvb_get_ntohl(tvb, offset + BITTORRENT_HEADER_LENGTH); if (4+typelen+1<=length) { if (!tvb_bytes_exist(tvb, offset + BITTORRENT_HEADER_LENGTH + 4, typelen+1)) return; for ( i=0 ; amp_messages[i].name ; i++ ) { if (strlen(amp_messages[i].name)==typelen && tvb_memeql(tvb, offset + BITTORRENT_HEADER_LENGTH + 4, amp_messages[i].name, strlen(amp_messages[i].name))==0) { prio = tvb_get_guint8(tvb, offset + BITTORRENT_HEADER_LENGTH + 4 + typelen); if (prio==0 || prio==1 || prio==2) { type = amp_messages[i].value; doffset = BITTORRENT_HEADER_LENGTH + 4 + typelen + 1; isamp = 1; } break; } } } } msgtype = match_strval(type, bittorrent_messages); /* if (msgtype == NULL && isamp) { msgtype = match_strval(type, azureus_messages); } */ if (msgtype == NULL) { proto_tree_add_text(tree, tvb, offset, -1, "Continuation data"); if (check_col(pinfo->cinfo, COL_INFO)) { col_set_str(pinfo->cinfo, COL_INFO, "Continuation data"); } return; } } else { /* not enough bytes of the header, stop here */ return; } if (isamp) { ti = proto_tree_add_item(tree, hf_azureus_msg, tvb, offset, length + BITTORRENT_HEADER_LENGTH, FALSE); } else { ti = proto_tree_add_item(tree, hf_bittorrent_msg, tvb, offset, length + BITTORRENT_HEADER_LENGTH, FALSE); } mtree = proto_item_add_subtree(ti, ett_bittorrent_msg); /* Keepalive message */ if (length == 0) { proto_tree_add_item(mtree, hf_bittorrent_msg_len, tvb, offset, BITTORRENT_HEADER_LENGTH, FALSE); if (check_col(pinfo->cinfo, COL_INFO)) { col_set_str(pinfo->cinfo, COL_INFO, "KeepAlive"); } return; } proto_tree_add_item(mtree, hf_bittorrent_msg_len, tvb, offset, BITTORRENT_HEADER_LENGTH, FALSE); offset += BITTORRENT_HEADER_LENGTH; /* If the tvb_bytes_exist() call above returned FALSE, this will throw an exception, so we won't use msgtype or type. */ if (isamp) { proto_tree_add_item(mtree, hf_azureus_msg_type_len, tvb, offset, 4, FALSE); proto_tree_add_item(mtree, hf_azureus_msg_type, tvb, offset+4, typelen, FALSE); proto_item_append_text(ti, ": Len %u, %s", length, msgtype); proto_tree_add_item(mtree, hf_azureus_msg_prio, tvb, offset+4+typelen, 1, FALSE); offset += 4+typelen+1; length -= 4+typelen+1; } else { proto_tree_add_item(mtree, hf_bittorrent_msg_type, tvb, offset, 1, FALSE); proto_item_append_text(ti, ": Len:%u, %s", length, msgtype); offset += 1; length -= 1; } if (check_col(pinfo->cinfo, COL_INFO)) { col_set_str(pinfo->cinfo, COL_INFO, msgtype); } switch (type) { case BITTORRENT_MESSAGE_CHOKE: case BITTORRENT_MESSAGE_UNCHOKE: case BITTORRENT_MESSAGE_INTERESTED: case BITTORRENT_MESSAGE_NOT_INTERESTED: /* No payload */ break; case BITTORRENT_MESSAGE_REQUEST: case BITTORRENT_MESSAGE_CANCEL: piece_index = tvb_get_ntohl(tvb, offset); proto_tree_add_uint(mtree, hf_bittorrent_piece_index, tvb, offset, 4, piece_index); offset += 4; piece_begin = tvb_get_ntohl(tvb, offset); proto_tree_add_uint(mtree, hf_bittorrent_piece_begin, tvb, offset, 4, piece_begin); offset += 4; piece_length = tvb_get_ntohl(tvb, offset); proto_tree_add_uint(mtree, hf_bittorrent_piece_length, tvb, offset, 4, piece_length); proto_item_append_text(ti, ", Piece (Idx:0x%x,Begin:0x%x,Len:0x%x)", piece_index, piece_begin, piece_length); if (check_col(pinfo->cinfo, COL_INFO)) { col_append_fstr(pinfo->cinfo, COL_INFO, ", Piece (Idx:0x%x,Begin:0x%x,Len:0x%x)", piece_index, piece_begin, piece_length); } break; case BITTORRENT_MESSAGE_HAVE: piece_index = tvb_get_ntohl(tvb, offset); proto_tree_add_item(mtree, hf_bittorrent_piece_index, tvb, offset, 4, FALSE); proto_item_append_text(ti, ", Piece (Idx:0x%x)", piece_index); if (check_col(pinfo->cinfo, COL_INFO)) { col_append_fstr(pinfo->cinfo, COL_INFO, ", Piece (Idx:0x%x)", piece_index); } break; case BITTORRENT_MESSAGE_BITFIELD: proto_tree_add_item(mtree, hf_bittorrent_bitfield_data, tvb, offset, length, FALSE); proto_item_append_text(ti, ", Len:0x%x", length); if (check_col(pinfo->cinfo, COL_INFO)) { col_append_fstr(pinfo->cinfo, COL_INFO, ", Len:0x%x", length); } break; case BITTORRENT_MESSAGE_PIECE: piece_index = tvb_get_ntohl(tvb, offset); proto_tree_add_uint(mtree, hf_bittorrent_piece_index, tvb, offset, 4, piece_index); offset += 4; length -= 4; piece_begin = tvb_get_ntohl(tvb, offset); proto_tree_add_item(mtree, hf_bittorrent_piece_begin, tvb, offset, 4, piece_begin); offset += 4; length -= 4; proto_tree_add_item(mtree, hf_bittorrent_piece_data, tvb, offset, length, FALSE); proto_item_append_text(ti, ", Idx:0x%x,Begin:0x%x,Len:0x%x", piece_index, piece_begin, length); if (check_col(pinfo->cinfo, COL_INFO)) { col_append_fstr(pinfo->cinfo, COL_INFO, ", Idx:0x%x,Begin:0x%x,Len:0x%x", piece_index, piece_begin, length); } break; case AZUREUS_MESSAGE_HANDSHAKE: case AZUREUS_MESSAGE_PEER_EXCHANGE: dissect_bencoding(tvb, pinfo, offset, length, mtree); break; case AZUREUS_MESSAGE_JPC_HELLO: stringlen = tvb_get_ntohl(tvb, offset); proto_tree_add_item(mtree, hf_azureus_jpc_addrlen, tvb, offset, 4, FALSE); proto_tree_add_item(mtree, hf_azureus_jpc_addr, tvb, offset+4, stringlen, FALSE); proto_tree_add_item(mtree, hf_azureus_jpc_port, tvb, offset+4+stringlen, 4, FALSE); proto_tree_add_item(mtree, hf_azureus_jpc_session, tvb, offset+4+stringlen+4, 4, FALSE); break; case AZUREUS_MESSAGE_JPC_REPLY: proto_tree_add_item(mtree, hf_azureus_jpc_session, tvb, offset, 4, FALSE); break; default: break; } } static void dissect_bittorrent_welcome (tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *tree) { int offset = 0; int i; char *version; if (check_col(pinfo->cinfo, COL_INFO)) { col_set_str(pinfo->cinfo, COL_INFO, "Handshake"); } proto_tree_add_item(tree, hf_bittorrent_prot_name_len, tvb, offset, 1, FALSE); offset+=1; proto_tree_add_item(tree, hf_bittorrent_prot_name, tvb, offset, 19, FALSE); offset += 19; proto_tree_add_item(tree, hf_bittorrent_reserved, tvb, offset, 8, FALSE); offset += 8; proto_tree_add_item(tree, hf_bittorrent_sha1_hash, tvb, offset, 20, FALSE); offset += 20; proto_tree_add_item(tree, hf_bittorrent_peer_id, tvb, offset, 20, FALSE); if(decode_client_information) { for(i = 0; peer_id[i].id[0] != '\0'; ++i) { if(tvb_memeql(tvb, offset, peer_id[i].id, strlen(peer_id[i].id)) == 0) { /* The version number is 4 numeric characters for the client ids beginning with '-' and 3 characters for the rest. */ version = tvb_get_string(tvb, offset + strlen(peer_id[i].id), (peer_id[i].id[0] == '-') ? 4 : 3); proto_tree_add_text(tree, tvb, offset, 20, "Client is %s v%s", peer_id[i].name, format_text(version, (peer_id[i].id[0] == '-') ? 4 : 3)); g_free(version); break; } } } offset += 20; } static void dissect_bittorrent_tcp_pdu (tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree) { proto_item *ti; if (check_col(pinfo->cinfo, COL_PROTOCOL)) { col_set_str(pinfo->cinfo, COL_PROTOCOL, "BitTorrent"); } if (check_col(pinfo->cinfo, COL_INFO)) { col_set_str(pinfo->cinfo, COL_INFO, "BitTorrent "); } ti = proto_tree_add_item (tree, proto_bittorrent, tvb, 0, -1, FALSE); tree = proto_item_add_subtree(ti, ett_bittorrent); if (tvb_get_guint8(tvb, 0) == 19 && tvb_memeql(tvb, 1, "BitTorrent protocol", 19) == 0) { dissect_bittorrent_welcome(tvb, pinfo, tree); } else { dissect_bittorrent_message(tvb, pinfo, tree); } if (check_col(pinfo->cinfo, COL_INFO)) { col_append_str(pinfo->cinfo, COL_INFO, " "); col_set_fence(pinfo->cinfo, COL_INFO); } } static void dissect_bittorrent (tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree) { tcp_dissect_pdus(tvb, pinfo, tree, bittorrent_desegment, BITTORRENT_HEADER_LENGTH, get_bittorrent_pdu_length, dissect_bittorrent_tcp_pdu); } static gboolean test_bittorrent_packet (tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree) { conversation_t *conversation; if (tvb_bytes_exist(tvb, 0, 20) && tvb_get_guint8(tvb, 0) == 19 && tvb_memeql(tvb, 1, "BitTorrent protocol", 19) == 0) { conversation = conversation_new (pinfo->fd->num, &pinfo->src, &pinfo->dst, pinfo->ptype, pinfo->srcport, pinfo->destport, 0); conversation_set_dissector(conversation, dissector_handle); dissect_bittorrent(tvb, pinfo, tree); return TRUE; } return FALSE; } void proto_register_bittorrent(void) { static hf_register_info hf[] = { { &hf_bittorrent_field_length, { "Field Length", "bittorrent.length", FT_UINT32, BASE_DEC, NULL, 0x0, "", HFILL } }, { &hf_bittorrent_prot_name_len, { "Protocol Name Length", "bittorrent.protocol.name.length", FT_UINT8, BASE_DEC, NULL, 0x0, "", HFILL } }, { &hf_bittorrent_prot_name, { "Protocol Name", "bittorrent.protocol.name", FT_STRING, BASE_DEC, NULL, 0x0, "", HFILL } }, { &hf_bittorrent_reserved, { "Reserved Extension Bytes", "bittorrent.reserved", FT_BYTES, BASE_DEC, NULL, 0x0, "", HFILL } }, { &hf_bittorrent_sha1_hash, { "SHA1 Hash of info dictionary", "bittorrent.info_hash", FT_BYTES, BASE_DEC, NULL, 0x0, "", HFILL } }, { &hf_bittorrent_peer_id, { "Peer ID", "bittorrent.peer_id", FT_BYTES, BASE_DEC, NULL, 0x0, "", HFILL } }, { &hf_bittorrent_msg, { "Message", "bittorrent.msg", FT_NONE, BASE_NONE, NULL, 0x0, "", HFILL } }, { &hf_bittorrent_msg_len, { "Message Length", "bittorrent.msg.length", FT_UINT32, BASE_DEC, NULL, 0x0, "", HFILL } }, { &hf_bittorrent_msg_type, { "Message Type", "bittorrent.msg.type", FT_UINT8, BASE_DEC, VALS(bittorrent_messages), 0x0, "", HFILL } }, { &hf_azureus_msg, { "Azureus Message", "bittorrent.azureus_msg", FT_NONE, BASE_NONE, NULL, 0x0, "", HFILL } }, { &hf_azureus_msg_type_len, { "Message Type Length", "bittorrent.msg.typelen", FT_UINT32, BASE_DEC, NULL, 0x0, "", HFILL } }, { &hf_azureus_msg_type, { "Message Type", "bittorrent.msg.aztype", FT_STRING, BASE_DEC, NULL, 0x0, "", HFILL } }, { &hf_azureus_msg_prio, { "Message Priority", "bittorrent.msg.prio", FT_UINT8, BASE_DEC, VALS(azureus_priorities), 0x0, "", HFILL } }, { &hf_bittorrent_bitfield_data, { "Bitfield data", "bittorrent.msg.bitfield", FT_BYTES, BASE_HEX, NULL, 0x0, "", HFILL } }, { &hf_bittorrent_piece_index, { "Piece index", "bittorrent.piece.index", FT_UINT32, BASE_HEX, NULL, 0x0, "", HFILL } }, { &hf_bittorrent_piece_begin, { "Begin offset of piece", "bittorrent.piece.begin", FT_UINT32, BASE_HEX, NULL, 0x0, "", HFILL } }, { &hf_bittorrent_piece_data, { "Data in a piece", "bittorrent.piece.data", FT_BYTES, BASE_HEX, NULL, 0x0, "", HFILL } }, { &hf_bittorrent_piece_length, { "Piece Length", "bittorrent.piece.length", FT_UINT32, BASE_HEX, NULL, 0x0, "", HFILL } }, { &hf_bittorrent_bstr_length, { "String Length", "bittorrent.bstr.length", FT_UINT32, BASE_DEC, NULL, 0x0, "", HFILL } }, { &hf_bittorrent_bstr, { "String", "bittorrent.bstr", FT_STRING, BASE_DEC, NULL, 0x0, "", HFILL } }, { &hf_bittorrent_bint, { "Integer", "bittorrent.bint", FT_INT32, BASE_DEC, NULL, 0x0, "", HFILL } }, { &hf_bittorrent_bdict, { "Dictionary", "bittorrent.bdict", FT_NONE, BASE_NONE, NULL, 0x0, "", HFILL } }, { &hf_bittorrent_bdict_entry, { "Entry", "bittorrent.bdict.entry", FT_NONE, BASE_NONE, NULL, 0x0, "", HFILL } }, { &hf_bittorrent_blist, { "List", "bittorrent.blist", FT_NONE, BASE_NONE, NULL, 0x0, "", HFILL } }, { &hf_azureus_jpc_addrlen, { "Cache Address Length", "bittorrent.jpc.addr.length", FT_UINT32, BASE_DEC, NULL, 0x0, "", HFILL } }, { &hf_azureus_jpc_addr, { "Cache Address", "bittorrent.jpc.addr", FT_STRING, BASE_DEC, NULL, 0x0, "", HFILL } }, { &hf_azureus_jpc_port, { "Port", "bittorrent.jpc.port", FT_UINT32, BASE_DEC, NULL, 0x0, "", HFILL } }, { &hf_azureus_jpc_session, { "Session ID", "bittorrent.jpc.session", FT_UINT32, BASE_HEX, NULL, 0x0, "", HFILL } } }; static gint *ett[] = { &ett_bittorrent, &ett_bittorrent_msg, &ett_peer_id, &ett_bittorrent_bdict, &ett_bittorrent_bdict_entry, &ett_bittorrent_blist }; module_t *bittorrent_module; proto_bittorrent = proto_register_protocol("BitTorrent", "BitTorrent", "bittorrent"); proto_register_field_array(proto_bittorrent, hf, array_length(hf)); proto_register_subtree_array(ett, array_length(ett)); register_dissector("bittorrent.tcp", dissect_bittorrent, proto_bittorrent); bittorrent_module = prefs_register_protocol(proto_bittorrent, NULL); prefs_register_bool_preference(bittorrent_module, "desegment", "Reassemble BitTorrent messages spanning multiple TCP segments", "Whether the BitTorrent dissector should reassemble messages spanning multiple TCP segments." " To use this option, you must also enable \"Allow subdissectors to reassemble TCP streams\" in the TCP protocol settings.", &bittorrent_desegment); prefs_register_bool_preference(bittorrent_module, "decode_client", "Decode the peer_id of the handshake messages", "Enabling this will tell which BitTorrent client that produced the handshake message", &decode_client_information); } void proto_reg_handoff_bittorrent(void) { /* dissector_handle = create_dissector_handle(dissect_bittorrent, proto_bittorrent); */ dissector_handle = find_dissector("bittorrent.tcp"); #if 0 dissector_add("tcp.port", 6881, dissector_handle); dissector_add("tcp.port", 6882, dissector_handle); dissector_add("tcp.port", 6883, dissector_handle); dissector_add("tcp.port", 6884, dissector_handle); dissector_add("tcp.port", 6885, dissector_handle); dissector_add("tcp.port", 6886, dissector_handle); dissector_add("tcp.port", 6887, dissector_handle); dissector_add("tcp.port", 6888, dissector_handle); dissector_add("tcp.port", 6889, dissector_handle); #endif heur_dissector_add("tcp", test_bittorrent_packet, proto_bittorrent); }