forked from osmocom/wireshark
5c8a909e06
temporary hack added to check for packets that look like RTPv2 packets and to dissect them as such (the right fix is to support starting and ending frames in conversations and to have H.245 close UDP conversations when appropriate and start new ones); add preferences for the UDP and TCP port numbers; add a preference to specify whether to use pre-corrigendum T.38 or post-corrigendum T.38; give a summary in the Info column. svn path=/trunk/; revision=9622
816 lines
26 KiB
C
816 lines
26 KiB
C
/* packet-t38.c
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* Routines for T.38 packet dissection
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* 2003 Hans Viens
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*
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* $Id: packet-t38.c,v 1.4 2004/01/09 23:24:54 guy Exp $
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*
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* Ethereal - Network traffic analyzer
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* By Gerald Combs <gerald@ethereal.com>
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* Copyright 1998 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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* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
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*/
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/* TO DO:
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* - Currently there is not support for T.38 IFP over TPKT over TCP,
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* just T.38 UDPTL over UDP and T.38 IFP packets directly over TCP.
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* - Currently no TCP desegmentation is done.
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* - SDP and H.245 dissectors should maybe be updated to start conversations for T.38 similar to RTP.
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* - It would be nice if we could dissect the T.30 data.
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* - Sometimes the last octet is not high-lighted when selecting something in the tree. Bug in PER dissector?
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*/
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#ifdef HAVE_CONFIG_H
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# include "config.h"
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#endif
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#include <glib.h>
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#include <epan/packet.h>
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#include <epan/conversation.h>
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#include <stdio.h>
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#include <string.h>
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#include "prefs.h"
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#include "ipproto.h"
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#include "packet-per.h"
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#include "prefs.h"
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#define PORT_T38 6004
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static guint global_t38_tcp_port = PORT_T38;
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static guint global_t38_udp_port = PORT_T38;
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/*
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* Variables to allow for proper deletion of dissector registration when
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* the user changes port from the gui.
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*/
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static guint tcp_port = 0;
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static guint udp_port = 0;
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/* dissect using the Pre Corrigendum T.38 ASN.1 specification (1998) */
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static gboolean use_pre_corrigendum_asn1_specification = TRUE;
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/* dissect packets that looks like RTP version 2 packets as RTP */
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/* instead of as T.38. This may result in that some T.38 UPTL */
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/* packets with sequence number values higher than 32767 may be */
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/* shown as RTP packets. */
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/* XXX - this should be handled by having starting and ending */
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/* frames for conversations and by having H.245 close conversations */
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/* and start new ones when appropriate. */
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static gboolean dissect_possible_rtpv2_packets_as_rtp = FALSE;
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static dissector_handle_t t38_handle;
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static dissector_handle_t rtp_handle;
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static guint32 Type_of_msg_value;
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static guint32 Data_Field_field_type_value;
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static guint32 Data_value;
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static guint32 T30ind_value;
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static int proto_t38 = -1;
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static int hf_t38_IFPPacket = -1;
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static int hf_t38_Type_of_msg = -1;
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static int hf_t38_t30_indicator = -1;
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static int hf_t38_data = -1;
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static int hf_t38_Data_Field = -1;
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static int hf_t38_Data_Field_item = -1;
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static int hf_t38_Data_Field_field_type = -1;
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static int hf_t38_Data_Field_field_data = -1;
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static int hf_t38_UDPTLPacket = -1;
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static int hf_t38_seq_number = -1;
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static int hf_t38_primary_ifp_packet = -1;
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static int hf_t38_primary_ifp_packet_length = -1;
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static int hf_t38_error_recovery = -1;
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static int hf_t38_secondary_ifp_packets = -1;
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static int hf_t38_secondary_ifp_packets_item = -1;
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static int hf_t38_secondary_ifp_packets_item_length = -1;
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static int hf_t38_fec_info = -1;
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static int hf_t38_fec_npackets = -1;
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static int hf_t38_fec_data = -1;
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static int hf_t38_fec_data_item = -1;
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static gint ett_t38 = -1;
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static gint ett_t38_IFPPacket = -1;
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static gint ett_t38_Type_of_msg = -1;
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static gint ett_t38_t30_indicator = -1;
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static gint ett_t38_data = -1;
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static gint ett_t38_Data_Field = -1;
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static gint ett_t38_Data_Field_item = -1;
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static gint ett_t38_Data_Field_field_type = -1;
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static gint ett_t38_UDPTLPacket = -1;
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static gint ett_t38_error_recovery = -1;
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static gint ett_t38_secondary_ifp_packets = -1;
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static gint ett_t38_fec_info = -1;
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static gint ett_t38_fec_data = -1;
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static gboolean primary_part = TRUE;
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static guint32 seq_number = 0;
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/* RTP Version is the first 2 bits of the first octet in the UDP payload*/
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#define RTP_VERSION(octet) ((octet) >> 6)
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void proto_reg_handoff_t38(void);
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static int
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dissect_t38_NULL(tvbuff_t *tvb _U_, int offset, packet_info *pinfo _U_, proto_tree *tree _U_)
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{
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return offset;
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}
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static per_choice_t t30_indicator_choice[] = {
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{ 0, "no-signal", ASN1_EXTENSION_ROOT,
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dissect_t38_NULL},
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{ 1, "cng", ASN1_EXTENSION_ROOT,
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dissect_t38_NULL},
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{ 2, "ced", ASN1_EXTENSION_ROOT,
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dissect_t38_NULL},
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{ 3, "v21-preamble", ASN1_EXTENSION_ROOT,
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dissect_t38_NULL},
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{ 4, "v27-2400-training", ASN1_EXTENSION_ROOT,
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dissect_t38_NULL},
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{ 5, "v27-4800-training", ASN1_EXTENSION_ROOT,
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dissect_t38_NULL},
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{ 6, "v29-7200-training", ASN1_EXTENSION_ROOT,
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dissect_t38_NULL},
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{ 7, "v29-9600-training", ASN1_EXTENSION_ROOT,
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dissect_t38_NULL},
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{ 8, "v17-7200-short-training", ASN1_EXTENSION_ROOT,
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dissect_t38_NULL},
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{ 9, "v17-7200-long-training", ASN1_EXTENSION_ROOT,
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dissect_t38_NULL},
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{ 10, "v17-9600-short-training", ASN1_EXTENSION_ROOT,
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dissect_t38_NULL},
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{ 11, "v17-9600-long-training", ASN1_EXTENSION_ROOT,
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dissect_t38_NULL},
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{ 12, "v17-12000-short-training", ASN1_EXTENSION_ROOT,
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dissect_t38_NULL},
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{ 13, "v17-12000-long-training", ASN1_EXTENSION_ROOT,
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dissect_t38_NULL},
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{ 14, "v17-14400-short-training", ASN1_EXTENSION_ROOT,
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dissect_t38_NULL},
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{ 15, "v17-14400-long-training", ASN1_EXTENSION_ROOT,
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dissect_t38_NULL},
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{ 16, "v8-ansam", ASN1_NOT_EXTENSION_ROOT,
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dissect_t38_NULL},
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{ 17, "v8-signal", ASN1_NOT_EXTENSION_ROOT,
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dissect_t38_NULL},
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{ 18, "v34-cntl-channel-1200", ASN1_NOT_EXTENSION_ROOT,
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dissect_t38_NULL},
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{ 19, "v34-pri-channel", ASN1_NOT_EXTENSION_ROOT,
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dissect_t38_NULL},
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{ 20, "v34-CC-retrain", ASN1_NOT_EXTENSION_ROOT,
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dissect_t38_NULL},
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{ 21, "v33-12000-training", ASN1_NOT_EXTENSION_ROOT,
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dissect_t38_NULL},
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{ 22, "v33-14400-training", ASN1_NOT_EXTENSION_ROOT,
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dissect_t38_NULL},
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{ 0, NULL, 0, NULL }
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};
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static const value_string t30_indicator_vals[] = {
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{ 0, "no-signal" },
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{ 1, "cng" },
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{ 2, "ced" },
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{ 3, "v21-preamble" },
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{ 4, "v27-2400-training" },
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{ 5, "v27-4800-training" },
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{ 6, "v29-7200-training" },
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{ 7, "v29-9600-training" },
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{ 8, "v17-7200-short-training" },
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{ 9, "v17-7200-long-training" },
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{ 10, "v17-9600-short-training" },
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{ 11, "v17-9600-long-training" },
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{ 12, "v17-12000-short-training" },
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{ 13, "v17-12000-long-training" },
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{ 14, "v17-14400-short-training" },
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{ 15, "v17-14400-long-training" },
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{ 16, "v8-ansam" },
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{ 17, "v8-signal" },
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{ 18, "v34-cntl-channel-1200" },
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{ 19, "v34-pri-channel" },
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{ 20, "v34-CC-retrain" },
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{ 21, "v33-12000-training" },
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{ 22, "v33-14400-training" },
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{ 0, NULL },
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};
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static int
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dissect_t38_t30_indicator(tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree)
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{
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offset=dissect_per_choice(tvb, offset, pinfo,
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tree, hf_t38_t30_indicator, ett_t38_t30_indicator,
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t30_indicator_choice, "T30 Indicator", &T30ind_value);
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if (check_col(pinfo->cinfo, COL_INFO) && primary_part){
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col_append_fstr(pinfo->cinfo, COL_INFO, " t30ind: %s",
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val_to_str(T30ind_value,t30_indicator_vals,"<unknown>"));
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}
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return offset;
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}
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static per_choice_t data_choice[] = {
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{ 0, "v21", ASN1_EXTENSION_ROOT,
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dissect_t38_NULL},
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{ 1, "v27-2400", ASN1_EXTENSION_ROOT,
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dissect_t38_NULL},
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{ 2, "v27-4800", ASN1_EXTENSION_ROOT,
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dissect_t38_NULL},
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{ 3, "v29-7200", ASN1_EXTENSION_ROOT,
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dissect_t38_NULL},
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{ 4, "v29-9600", ASN1_EXTENSION_ROOT,
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dissect_t38_NULL},
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{ 5, "v17-7200", ASN1_EXTENSION_ROOT,
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dissect_t38_NULL},
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{ 6, "v17-9600", ASN1_EXTENSION_ROOT,
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dissect_t38_NULL},
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{ 7, "v17-12000", ASN1_EXTENSION_ROOT,
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dissect_t38_NULL},
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{ 8, "v17-14400", ASN1_EXTENSION_ROOT,
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dissect_t38_NULL},
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{ 9, "v8", ASN1_NOT_EXTENSION_ROOT,
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dissect_t38_NULL},
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{ 10, "v34-pri-rate", ASN1_NOT_EXTENSION_ROOT,
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dissect_t38_NULL},
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{ 11, "v34-CC-1200", ASN1_NOT_EXTENSION_ROOT,
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dissect_t38_NULL},
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{ 12, "v34-pri-ch", ASN1_NOT_EXTENSION_ROOT,
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dissect_t38_NULL},
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{ 13, "v33-12000", ASN1_NOT_EXTENSION_ROOT,
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dissect_t38_NULL},
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{ 14, "v33-14400", ASN1_NOT_EXTENSION_ROOT,
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dissect_t38_NULL},
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{ 0, NULL, 0, NULL }
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};
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static const value_string data_vals[] = {
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{ 0, "v21" },
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{ 1, "v27-2400" },
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{ 2, "v27-4800" },
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{ 3, "v29-7200" },
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{ 4, "v29-9600" },
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{ 5, "v17-7200" },
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{ 6, "v17-9600" },
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{ 7, "v17-12000" },
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{ 8, "v17-14400" },
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{ 9, "v8" },
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{ 10, "v34-pri-rate" },
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{ 11, "v34-CC-1200" },
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{ 12, "v34-pri-ch" },
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{ 13, "v33-12000" },
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{ 14, "v33-14400" },
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{ 0, NULL },
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};
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static int
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dissect_t38_data(tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree)
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{
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offset=dissect_per_choice(tvb, offset, pinfo,
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tree, hf_t38_data, ett_t38_data,
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data_choice, "data", &Data_value);
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if (check_col(pinfo->cinfo, COL_INFO) && primary_part){
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col_append_fstr(pinfo->cinfo, COL_INFO, " data:%s:",
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val_to_str(Data_value,data_vals,"<unknown>"));
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}
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return offset;
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}
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static per_choice_t Type_of_msg_choice[] = {
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{ 0, "t30-indicator", ASN1_NO_EXTENSIONS,
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dissect_t38_t30_indicator},
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{ 1, "data", ASN1_NO_EXTENSIONS,
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dissect_t38_data},
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{ 0, NULL, 0, NULL }
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};
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static const value_string Type_of_msg_vals[] = {
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{ 0, "t30-indicator" },
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{ 1, "data" },
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{ 0, NULL}
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};
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static int
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dissect_t38_Type_of_msg(tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree)
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{
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offset=dissect_per_choice(tvb, offset, pinfo,
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tree, hf_t38_Type_of_msg, ett_t38_Type_of_msg,
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Type_of_msg_choice, "Type of message", &Type_of_msg_value);
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return offset;
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}
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static per_choice_t Data_Field_field_type_PreCorrigendum_choice[] = {
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{ 0, "hdlc-data", ASN1_NO_EXTENSIONS,
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dissect_t38_NULL},
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{ 1, "hdlc-sig-end", ASN1_NO_EXTENSIONS,
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dissect_t38_NULL},
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{ 2, "hdlc-fcs-OK", ASN1_NO_EXTENSIONS,
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dissect_t38_NULL},
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{ 3, "hdlc-fcs-BAD", ASN1_NO_EXTENSIONS,
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dissect_t38_NULL},
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{ 4, "hdlc-fcs-OK-sig-end", ASN1_NO_EXTENSIONS,
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dissect_t38_NULL},
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{ 5, "hdlc-fcs-BAD-sig-end", ASN1_NO_EXTENSIONS,
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dissect_t38_NULL},
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{ 6, "t4-non-ecm-data", ASN1_NO_EXTENSIONS,
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dissect_t38_NULL},
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{ 7, "t4-non-ecm-sig-end", ASN1_NO_EXTENSIONS,
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dissect_t38_NULL},
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{ 0, NULL, 0, NULL }
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};
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static per_choice_t Data_Field_field_type_choice[] = {
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{ 0, "hdlc-data", ASN1_EXTENSION_ROOT,
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dissect_t38_NULL},
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{ 1, "hdlc-sig-end", ASN1_EXTENSION_ROOT,
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dissect_t38_NULL},
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{ 2, "hdlc-fcs-OK", ASN1_EXTENSION_ROOT,
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dissect_t38_NULL},
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{ 3, "hdlc-fcs-BAD", ASN1_EXTENSION_ROOT,
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dissect_t38_NULL},
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{ 4, "hdlc-fcs-OK-sig-end", ASN1_EXTENSION_ROOT,
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dissect_t38_NULL},
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{ 5, "hdlc-fcs-BAD-sig-end", ASN1_EXTENSION_ROOT,
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dissect_t38_NULL},
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{ 6, "t4-non-ecm-data", ASN1_EXTENSION_ROOT,
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dissect_t38_NULL},
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{ 7, "t4-non-ecm-sig-end", ASN1_EXTENSION_ROOT,
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dissect_t38_NULL},
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{ 0, NULL, 0, NULL }
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};
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static const value_string Data_Field_field_type_vals[] = {
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{ 0, "hdlc-data" },
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{ 1, "hdlc-sig-end" },
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{ 2, "hdlc-fcs-OK" },
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{ 3, "hdlc-fcs-BAD" },
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{ 4, "hdlc-fcs-OK-sig-end" },
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{ 5, "hdlc-fcs-BAD-sig-end" },
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{ 6, "t4-non-ecm-data" },
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{ 7, "t4-non-ecm-sig-end" },
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{ 0, NULL },
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};
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static int
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dissect_t38_Data_Field_field_type(tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree)
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{
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if(use_pre_corrigendum_asn1_specification){
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offset=dissect_per_choice(tvb, offset, pinfo,
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tree, hf_t38_Data_Field_field_type, ett_t38_Data_Field_field_type,
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Data_Field_field_type_PreCorrigendum_choice, "Field Type", &Data_Field_field_type_value);
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}
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else{
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offset=dissect_per_choice(tvb, offset, pinfo,
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tree, hf_t38_Data_Field_field_type, ett_t38_Data_Field_field_type,
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Data_Field_field_type_choice, "Field Type", &Data_Field_field_type_value);
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}
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if (check_col(pinfo->cinfo, COL_INFO) && primary_part){
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col_append_fstr(pinfo->cinfo, COL_INFO, " %s",
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val_to_str(Data_Field_field_type_value,Data_Field_field_type_vals,"<unknown>"));
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}
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return offset;
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}
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static int
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dissect_t38_Data_Field_field_data(tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree)
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{
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guint32 value_offset = 0;
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guint32 value_len = 0;
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offset=dissect_per_octet_string(tvb, offset, pinfo,
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tree, hf_t38_Data_Field_field_data, 1, 65535,
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&value_offset, &value_len);
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if (check_col(pinfo->cinfo, COL_INFO) && primary_part){
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if(value_len < 8){
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col_append_fstr(pinfo->cinfo, COL_INFO, "[%s]",
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tvb_bytes_to_str(tvb,value_offset,value_len));
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}
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else {
|
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col_append_fstr(pinfo->cinfo, COL_INFO, "[%s...]",
|
|
tvb_bytes_to_str(tvb,value_offset,7));
|
|
}
|
|
}
|
|
return offset;
|
|
}
|
|
|
|
static per_sequence_t Data_Field_item_sequence[] = {
|
|
{ "field-type", ASN1_NO_EXTENSIONS, ASN1_NOT_OPTIONAL,
|
|
dissect_t38_Data_Field_field_type },
|
|
{ "field-data", ASN1_NO_EXTENSIONS, ASN1_OPTIONAL,
|
|
dissect_t38_Data_Field_field_data },
|
|
{ NULL, 0, 0, NULL }
|
|
};
|
|
|
|
static int
|
|
dissect_t38_Data_Field_item(tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree)
|
|
{
|
|
offset=dissect_per_sequence(tvb, offset, pinfo,
|
|
tree, hf_t38_Data_Field_item, ett_t38_Data_Field_item,
|
|
Data_Field_item_sequence);
|
|
return offset;
|
|
}
|
|
|
|
static int
|
|
dissect_t38_Data_Field(tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree)
|
|
{
|
|
offset=dissect_per_sequence_of(tvb, offset, pinfo,
|
|
tree, hf_t38_Data_Field, ett_t38_Data_Field,
|
|
dissect_t38_Data_Field_item);
|
|
return offset;
|
|
}
|
|
|
|
static per_sequence_t IFPPacket_sequence[] = {
|
|
{ "type-of-msg", ASN1_NO_EXTENSIONS, ASN1_NOT_OPTIONAL,
|
|
dissect_t38_Type_of_msg },
|
|
{ "data-field", ASN1_NO_EXTENSIONS, ASN1_OPTIONAL,
|
|
dissect_t38_Data_Field },
|
|
{ NULL, 0, 0, NULL }
|
|
};
|
|
|
|
static int
|
|
dissect_t38_IFPPacket(tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree)
|
|
{
|
|
offset=dissect_per_sequence(tvb, offset, pinfo,
|
|
tree, hf_t38_IFPPacket, ett_t38_IFPPacket,
|
|
IFPPacket_sequence);
|
|
return offset;
|
|
}
|
|
|
|
static int
|
|
dissect_t38_seq_number(tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree)
|
|
{
|
|
offset=dissect_per_constrained_integer(tvb, offset, pinfo,
|
|
tree, hf_t38_seq_number, 0, 65535,
|
|
&seq_number, NULL, FALSE);
|
|
|
|
if (check_col(pinfo->cinfo, COL_INFO)){
|
|
col_append_fstr(pinfo->cinfo, COL_INFO, "Seq=%05u ",seq_number);
|
|
}
|
|
return offset;
|
|
}
|
|
|
|
static int
|
|
dissect_t38_primary_ifp_packet(tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree)
|
|
{
|
|
guint32 length;
|
|
primary_part = TRUE;
|
|
|
|
offset=dissect_per_length_determinant(tvb, offset, pinfo,
|
|
tree, hf_t38_primary_ifp_packet_length, &length);
|
|
offset=dissect_t38_IFPPacket(tvb, offset, pinfo, tree);
|
|
return offset;
|
|
}
|
|
|
|
static int
|
|
dissect_t38_secondary_ifp_packets_item(tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree)
|
|
{
|
|
guint32 length;
|
|
|
|
offset=dissect_per_length_determinant(tvb, offset, pinfo,
|
|
tree, hf_t38_secondary_ifp_packets_item_length, &length);
|
|
offset=dissect_t38_IFPPacket(tvb, offset, pinfo, tree);
|
|
return offset;
|
|
}
|
|
|
|
static int
|
|
dissect_t38_secondary_ifp_packets(tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree)
|
|
{
|
|
/* When the field-data is not present, we MUST offset 1 byte*/
|
|
if((Data_Field_field_type_value != 0) &&
|
|
(Data_Field_field_type_value != 6))
|
|
{
|
|
offset=offset+8;
|
|
}
|
|
|
|
offset=dissect_per_sequence_of(tvb, offset, pinfo,
|
|
tree, hf_t38_secondary_ifp_packets, ett_t38_secondary_ifp_packets,
|
|
dissect_t38_secondary_ifp_packets_item);
|
|
return offset;
|
|
}
|
|
|
|
static int
|
|
dissect_t38_fec_npackets(tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree)
|
|
{
|
|
offset=dissect_per_integer(tvb, offset, pinfo,
|
|
tree, hf_t38_fec_npackets,
|
|
NULL, NULL);
|
|
return offset;
|
|
}
|
|
|
|
static int
|
|
dissect_t38_fec_data_item(tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree)
|
|
{
|
|
offset=dissect_per_octet_string(tvb, offset, pinfo,
|
|
tree, hf_t38_fec_data_item, -1, -1,
|
|
NULL, NULL);
|
|
return offset;
|
|
}
|
|
|
|
static int
|
|
dissect_t38_fec_data(tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree)
|
|
{
|
|
offset=dissect_per_sequence_of(tvb, offset, pinfo,
|
|
tree, hf_t38_fec_data, ett_t38_fec_data,
|
|
dissect_t38_fec_data_item);
|
|
return offset;
|
|
}
|
|
|
|
static per_sequence_t fec_info_sequence[] = {
|
|
{ "fec-npackets", ASN1_NO_EXTENSIONS, ASN1_NOT_OPTIONAL,
|
|
dissect_t38_fec_npackets },
|
|
{ "fec-data", ASN1_NO_EXTENSIONS, ASN1_NOT_OPTIONAL,
|
|
dissect_t38_fec_data },
|
|
{ NULL, 0, 0, NULL }
|
|
};
|
|
|
|
static int
|
|
dissect_t38_fec_info(tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree)
|
|
{
|
|
offset=dissect_per_sequence(tvb, offset, pinfo,
|
|
tree, hf_t38_fec_info, ett_t38_fec_info,
|
|
fec_info_sequence);
|
|
return offset;
|
|
}
|
|
|
|
static per_choice_t error_recovery_choice[] = {
|
|
{ 0, "secondary-ifp-packets", ASN1_NO_EXTENSIONS,
|
|
dissect_t38_secondary_ifp_packets},
|
|
{ 1, "fec-info", ASN1_NO_EXTENSIONS,
|
|
dissect_t38_fec_info},
|
|
{ 0, NULL, 0, NULL }
|
|
};
|
|
|
|
static const value_string error_recovery_vals[] = {
|
|
{ 0, "secondary-ifp-packets" },
|
|
{ 1, "fec-info" },
|
|
{ 0, NULL}
|
|
};
|
|
|
|
static int
|
|
dissect_t38_error_recovery(tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree)
|
|
{
|
|
primary_part = FALSE;
|
|
|
|
offset=dissect_per_choice(tvb, offset, pinfo,
|
|
tree, hf_t38_error_recovery, ett_t38_error_recovery,
|
|
error_recovery_choice, "Error recovery", NULL);
|
|
|
|
primary_part = TRUE;
|
|
|
|
return offset;
|
|
}
|
|
|
|
static per_sequence_t UDPTLPacket_sequence[] = {
|
|
{ "seq-number", ASN1_NO_EXTENSIONS, ASN1_NOT_OPTIONAL,
|
|
dissect_t38_seq_number },
|
|
{ "primary-ifp-packet", ASN1_NO_EXTENSIONS, ASN1_NOT_OPTIONAL,
|
|
dissect_t38_primary_ifp_packet },
|
|
{ "error-recovery", ASN1_NO_EXTENSIONS, ASN1_NOT_OPTIONAL,
|
|
dissect_t38_error_recovery },
|
|
{ NULL, 0, 0, NULL }
|
|
};
|
|
|
|
static int
|
|
dissect_t38_UDPTLPacket(tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree)
|
|
{
|
|
/* Initialize to something else than data type */
|
|
Data_Field_field_type_value = 1;
|
|
|
|
offset=dissect_per_sequence(tvb, offset, pinfo,
|
|
tree, hf_t38_UDPTLPacket, ett_t38_UDPTLPacket,
|
|
UDPTLPacket_sequence);
|
|
return offset;
|
|
}
|
|
|
|
/* Entry point for dissection */
|
|
static void
|
|
dissect_t38_udp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
|
|
{
|
|
proto_item *it;
|
|
proto_tree *tr;
|
|
guint32 offset=0;
|
|
|
|
if (check_col(pinfo->cinfo, COL_PROTOCOL)){
|
|
col_set_str(pinfo->cinfo, COL_PROTOCOL, "T.38");
|
|
}
|
|
if (check_col(pinfo->cinfo, COL_INFO)){
|
|
col_clear(pinfo->cinfo, COL_INFO);
|
|
}
|
|
|
|
it=proto_tree_add_protocol_format(tree, proto_t38, tvb, 0, tvb_length(tvb),
|
|
"ITU-T Recommendation T.38");
|
|
tr=proto_item_add_subtree(it, ett_t38);
|
|
|
|
if (check_col(pinfo->cinfo, COL_INFO)){
|
|
col_append_fstr(pinfo->cinfo, COL_INFO, "UDP: UDPTLPacket ");
|
|
}
|
|
|
|
offset=dissect_t38_UDPTLPacket(tvb, offset, pinfo, tr);
|
|
|
|
}
|
|
|
|
static void
|
|
dissect_t38_tcp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
|
|
{
|
|
proto_item *it;
|
|
proto_tree *tr;
|
|
guint32 offset=0;
|
|
|
|
if (check_col(pinfo->cinfo, COL_PROTOCOL)){
|
|
col_set_str(pinfo->cinfo, COL_PROTOCOL, "T.38");
|
|
}
|
|
if (check_col(pinfo->cinfo, COL_INFO)){
|
|
col_clear(pinfo->cinfo, COL_INFO);
|
|
}
|
|
|
|
it=proto_tree_add_protocol_format(tree, proto_t38, tvb, 0, tvb_length(tvb),
|
|
"ITU-T Recommendation T.38");
|
|
tr=proto_item_add_subtree(it, ett_t38);
|
|
|
|
if (check_col(pinfo->cinfo, COL_INFO)){
|
|
col_append_fstr(pinfo->cinfo, COL_INFO, "TCP: IFPPacket");
|
|
}
|
|
|
|
offset=dissect_t38_IFPPacket(tvb, offset, pinfo, tr);
|
|
|
|
}
|
|
|
|
static void
|
|
dissect_t38(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
|
|
{
|
|
guint8 octet1;
|
|
unsigned int offset = 0;
|
|
primary_part = TRUE;
|
|
|
|
if(pinfo->ipproto == IP_PROTO_TCP)
|
|
{
|
|
dissect_t38_tcp(tvb, pinfo, tree);
|
|
}
|
|
else if(pinfo->ipproto == IP_PROTO_UDP)
|
|
{
|
|
if(dissect_possible_rtpv2_packets_as_rtp){
|
|
octet1 = tvb_get_guint8( tvb, offset );
|
|
if(RTP_VERSION(octet1) == 2){
|
|
call_dissector(rtp_handle,tvb,pinfo,tree);
|
|
return;
|
|
}
|
|
}
|
|
dissect_t38_udp(tvb, pinfo, tree);
|
|
}
|
|
}
|
|
|
|
/* Ethereal Protocol Registration */
|
|
void
|
|
proto_register_t38(void)
|
|
{
|
|
static hf_register_info hf[] =
|
|
{
|
|
{ &hf_t38_IFPPacket,
|
|
{ "IFPPacket", "t38.IFPPacket", FT_NONE, BASE_NONE,
|
|
NULL, 0, "IFPPacket sequence", HFILL }},
|
|
{ &hf_t38_Type_of_msg,
|
|
{ "Type of msg", "t38.Type_of_msg_type", FT_UINT32, BASE_DEC,
|
|
VALS(Type_of_msg_vals), 0, "Type_of_msg choice", HFILL }},
|
|
{ &hf_t38_t30_indicator,
|
|
{ "T30 indicator", "t38.t30_indicator", FT_UINT32, BASE_DEC,
|
|
VALS(t30_indicator_vals), 0, "t30_indicator", HFILL }},
|
|
{ &hf_t38_data,
|
|
{ "data", "t38.t38_data", FT_UINT32, BASE_DEC,
|
|
VALS(data_vals), 0, "data", HFILL }},
|
|
{ &hf_t38_Data_Field,
|
|
{ "Data Field", "t38.Data_Field", FT_NONE, BASE_NONE,
|
|
NULL, 0, "Data_Field sequence of", HFILL }},
|
|
{ &hf_t38_Data_Field_item,
|
|
{ "Data_Field_item", "t38.Data_Field_item", FT_NONE, BASE_NONE,
|
|
NULL, 0, "Data_Field_item sequence", HFILL }},
|
|
{ &hf_t38_Data_Field_field_type,
|
|
{ "Data_Field_field_type", "t38.Data_Field_field_type", FT_UINT32, BASE_DEC,
|
|
VALS(Data_Field_field_type_vals), 0, "Data_Field_field_type choice", HFILL }},
|
|
{ &hf_t38_Data_Field_field_data,
|
|
{ "Data_Field_field_data", "t38.Data_Field_field_data", FT_BYTES, BASE_HEX,
|
|
NULL, 0, "Data_Field_field_data octet string", HFILL }},
|
|
{ &hf_t38_UDPTLPacket,
|
|
{ "UDPTLPacket", "t38.UDPTLPacket", FT_NONE, BASE_NONE,
|
|
NULL, 0, "UDPTLPacket sequence", HFILL }},
|
|
{ &hf_t38_seq_number,
|
|
{ "Sequence number", "t38.seq_number", FT_UINT32, BASE_DEC,
|
|
NULL, 0, "seq_number", HFILL }},
|
|
{ &hf_t38_primary_ifp_packet,
|
|
{ "Primary IFPPacket", "t38.primary_ifp_packet", FT_BYTES, BASE_HEX,
|
|
NULL, 0, "primary_ifp_packet octet string", HFILL }},
|
|
{ &hf_t38_primary_ifp_packet_length,
|
|
{ "primary_ifp_packet_length", "t38.primary_ifp_packet_length", FT_UINT32, BASE_DEC,
|
|
NULL, 0, "primary_ifp_packet_length", HFILL }},
|
|
{ &hf_t38_error_recovery,
|
|
{ "Error recovery", "t38.error_recovery", FT_UINT32, BASE_DEC,
|
|
VALS(error_recovery_vals), 0, "error_recovery choice", HFILL }},
|
|
{ &hf_t38_secondary_ifp_packets,
|
|
{ "Secondary IFPPackets", "t38.secondary_ifp_packets", FT_NONE, BASE_NONE,
|
|
NULL, 0, "secondary_ifp_packets sequence of", HFILL }},
|
|
{ &hf_t38_secondary_ifp_packets_item,
|
|
{ "Secondary IFPPackets item", "t38.secondary_ifp_packets_item", FT_BYTES, BASE_HEX,
|
|
NULL, 0, "secondary_ifp_packets_item octet string", HFILL }},
|
|
{ &hf_t38_secondary_ifp_packets_item_length,
|
|
{ "secondary_ifp_packets_item_length", "t38.secondary_ifp_packets_item_length", FT_UINT32, BASE_DEC,
|
|
NULL, 0, "secondary_ifp_packets_item_length", HFILL }},
|
|
{ &hf_t38_fec_info,
|
|
{ "Fec info", "t38.fec_info", FT_NONE, BASE_NONE,
|
|
NULL, 0, "fec_info sequence", HFILL }},
|
|
{ &hf_t38_fec_npackets,
|
|
{ "Fec npackets", "h245.fec_npackets", FT_INT32, BASE_DEC,
|
|
NULL, 0, "fec_npackets value", HFILL }},
|
|
{ &hf_t38_fec_data,
|
|
{ "Fec data", "t38.fec_data", FT_NONE, BASE_NONE,
|
|
NULL, 0, "fec_data sequence of", HFILL }},
|
|
{ &hf_t38_fec_data_item,
|
|
{ "t38_fec_data_item", "t38.t38_fec_data_item", FT_BYTES, BASE_HEX,
|
|
NULL, 0, "t38_fec_data_item octet string", HFILL }},
|
|
};
|
|
|
|
static gint *ett[] =
|
|
{
|
|
&ett_t38,
|
|
&ett_t38_IFPPacket,
|
|
&ett_t38_Type_of_msg,
|
|
&ett_t38_t30_indicator,
|
|
&ett_t38_data,
|
|
&ett_t38_Data_Field,
|
|
&ett_t38_Data_Field_item,
|
|
&ett_t38_Data_Field_field_type,
|
|
&ett_t38_UDPTLPacket,
|
|
&ett_t38_error_recovery,
|
|
&ett_t38_secondary_ifp_packets,
|
|
&ett_t38_fec_info,
|
|
&ett_t38_fec_data,
|
|
};
|
|
module_t *t38_module;
|
|
|
|
proto_t38 = proto_register_protocol("T38", "T38", "t38");
|
|
proto_register_field_array(proto_t38, hf, array_length(hf));
|
|
proto_register_subtree_array(ett, array_length(ett));
|
|
register_dissector("t38", dissect_t38, proto_t38);
|
|
|
|
t38_module = prefs_register_protocol(proto_t38, proto_reg_handoff_t38);
|
|
prefs_register_bool_preference(t38_module, "use_pre_corrigendum_asn1_specification",
|
|
"Use the Pre-Corrigendum ASN.1 specification",
|
|
"Whether the T.38 dissector should decode using the Pre-Corrigendum T.38 "
|
|
"ASN.1 specification (1998).",
|
|
&use_pre_corrigendum_asn1_specification);
|
|
prefs_register_bool_preference(t38_module, "dissect_possible_rtpv2_packets_as_rtp",
|
|
"Dissect possible RTP version 2 packets with RTP dissector",
|
|
"Whether a UDP packet that looks like RTP version 2 packet will "
|
|
"be dissected as RTP packet or T.38 packet. If enabled there is a risk that T.38 UDPTL "
|
|
"packets with sequence number higher than 32767 may be dissected as RTP.",
|
|
&dissect_possible_rtpv2_packets_as_rtp);
|
|
prefs_register_uint_preference(t38_module, "tcp.port",
|
|
"T.38 TCP Port",
|
|
"Set the TCP port for T.38 messages",
|
|
10, &global_t38_tcp_port);
|
|
prefs_register_uint_preference(t38_module, "udp.port",
|
|
"T.38 UDP Port",
|
|
"Set the UDP port for T.38 messages",
|
|
10, &global_t38_udp_port);
|
|
|
|
}
|
|
|
|
void
|
|
proto_reg_handoff_t38(void)
|
|
{
|
|
static int t38_prefs_initialized = FALSE;
|
|
|
|
if (!t38_prefs_initialized) {
|
|
t38_handle=create_dissector_handle(dissect_t38, proto_t38);
|
|
t38_prefs_initialized = TRUE;
|
|
}
|
|
else {
|
|
dissector_delete("tcp.port", tcp_port, t38_handle);
|
|
dissector_delete("udp.port", udp_port, t38_handle);
|
|
}
|
|
tcp_port = global_t38_tcp_port;
|
|
udp_port = global_t38_udp_port;
|
|
|
|
dissector_add("tcp.port", tcp_port, t38_handle);
|
|
dissector_add("udp.port", udp_port, t38_handle);
|
|
|
|
rtp_handle = find_dissector("rtp");
|
|
}
|