path: root/epan/dissectors/packet-rtp-events.c

/* packet-rtp-events.c
 *
 * Routines for RFC 2833 RTP Events dissection
 * Copyright 2003, Kevin A. Noll <knoll[AT]poss.com>
 *
 * Wireshark - Network traffic analyzer
 * By Gerald Combs <gerald@wireshark.org>
 * Copyright 1998 Gerald Combs
 *
 * SPDX-License-Identifier: GPL-2.0-or-later
 * Ref http://www.ietf.org/rfc/rfc4733.txt?number=4733
 */

/*
 * This dissector tries to dissect RTP Events.
 *
 * Cisco NSE is now supported, additions by
 *                Gonzalo Salgueiro <gsalguei@cisco.com>
 *          Chidambaram Arunachalam <carunach@cisco.com>
 * Copyright 2008, Cisco Systems, Inc.
 */


#include "config.h"

#include <epan/packet.h>
#include <epan/prefs.h>
#include <epan/proto_data.h>

#include "packet-rtp-events.h"
#include "packet-rtp.h"
#include <epan/tap.h>

void proto_register_rtp_events(void);
void proto_reg_handoff_rtp_events(void);

/*  rtp_event_payload_type_value is the value used globally
	to set the appropriate payload type
*/
static guint rtp_event_payload_type_value = 101;

/*  cisco_nse_pt_value is used globally
	to set the appropriate Cisco NSE payload type value
 */
static guint cisco_nse_pt_value = 100;


/* RTP Event Fields */

static int proto_rtp_events = -1;
static int rtp_event_tap = -1;

static int hf_rtp_events_event = -1;	/* one byte */
static int hf_rtp_events_end = -1;	/* one bit */
static int hf_rtp_events_reserved = -1; /* one bit */
static int hf_rtp_events_volume = -1;	/* six bits */
static int hf_rtp_events_duration = -1; /* sixteen bits */


#define RTP_DTMF_0	0
#define RTP_DTMF_1	1
#define RTP_DTMF_2	2
#define RTP_DTMF_3	3
#define RTP_DTMF_4	4
#define RTP_DTMF_5	5
#define RTP_DTMF_6	6
#define RTP_DTMF_7	7
#define RTP_DTMF_8	8
#define RTP_DTMF_9	9
#define RTP_DTMF_STAR	10
#define RTP_DTMF_POUND	11
#define RTP_DTMF_A	12
#define RTP_DTMF_B	13
#define RTP_DTMF_C	14
#define RTP_DTMF_D	15
#define RTP_DTMF_FLASH	16

#define RTP_ANS		32
#define RTP_ANSREV	33
#define RTP_ANSAM	34
#define RTP_ANSAMREV	35
#define RTP_CNG		36
#define RTP_V21C1B0	37
#define RTP_V21C1B1	38
#define RTP_V21C2B0	39
#define RTP_V21C2B1	40
#define RTP_CRDI	41
#define RTP_CRDR	42
#define RTP_CRE		43
#define RTP_ESI		44
#define RTP_ESR		45
#define RTP_MRDI	46
#define RTP_MRDR	47
#define RTP_MRE		48
#define RTP_CT		49

#define RTP_OFFHOOK	64
#define RTP_ONHOOK	65
#define RTP_DIALTONE	66
#define RTP_INTDT	67
#define RTP_SPCDT	68
#define RTP_2NDDT	69
#define RTP_RGTONE	70
#define RTP_SPRGTONE	71
#define RTP_BUSYTONE	72
#define RTP_CNGTONE	73
#define RTP_SPINFOTN	74
#define RTP_CMFTTONE	75
#define RTP_HOLDTONE	76
#define RTP_RECTONE	77
#define RTP_CLRWTTONE	78
#define RTP_CWTONE	79
#define RTP_PAYTONE	80
#define RTP_POSINDTONE	81
#define RTP_NEGINDTONE	82
#define RTP_WARNTONE	83
#define RTP_INTRTONE	84
#define RTP_CALLCDTONE	85
#define RTP_PAYPHONE	86
#define RTP_CAS		87
#define RTP_OFFHKWARN	88
#define RTP_RING	89

#define RTP_ACCPTTONE	96
#define RTP_CONFIRMTN	97
#define RTP_DLTNRECALL	98
#define RTP_END3WAYTN	99
#define RTP_FACTONE	100
#define RTP_LNLOCKTN	101
#define RTP_NUMUNOBT	102
#define RTP_OFFERGTONE	103
#define RTP_PERMSIGTN	104
#define RTP_PREEMPTTN	105
#define RTP_QUETONE	106
#define RTP_REFUSALTN	107
#define RTP_ROUTETONE	108
#define RTP_VALIDTONE	109
#define RTP_WAITGTONE	110
#define RTP_WARNEOPTN	111
#define RTP_WARNPIPTN	112

#define RTP_MF0		128
#define RTP_MF1		129
#define RTP_MF2		130
#define RTP_MF3		131
#define RTP_MF4		132
#define RTP_MF5		133
#define RTP_MF6		134
#define RTP_MF7		135
#define RTP_MF8		136
#define RTP_MF9		137
#define RTP_K0		138
#define RTP_K1		139
#define RTP_K2		140
#define RTP_S0		141
#define RTP_S1		142
#define RTP_S3		143

#define RTP_WINK	160
#define RTP_WINKOFF	161
#define RTP_INCSEIZ	162
#define RTP_SEIZURE	163
#define RTP_UNSEIZE	164
#define RTP_COT		165
#define RTP_DEFCOT	166
#define RTP_COTTONE	167
#define RTP_COTSEND	168

#define RTP_COTVERFD	170
#define RTP_LOOPBACK	171
#define RTP_MWATTTONE	172
#define RTP_NEWMWATTTN	173

#define RTP_CISCO_NSE_FAX_PASSTHROUGH_IND    192
#define RTP_CISCO_NSE_MODEM_PASSTHROUGH_IND  193
#define RTP_CISCO_NSE_VOICE_MODE_IND         194
#define RTP_CISCO_NSE_MODEM_RELAY_CAP_IND    199
#define RTP_CISCO_NSE_FAX_RELAY_IND          200
#define RTP_CISCO_NSE_ACK                    201
#define RTP_CISCO_NSE_NACK                   202
#define RTP_CISCO_NSE_MODEM_RELAY_IND        203


static const value_string rtp_event_type_values[] =
{
	{ RTP_DTMF_0,			       "DTMF Zero 0" },
	{ RTP_DTMF_1,			       "DTMF One 1" },
	{ RTP_DTMF_2,			       "DTMF Two 2" },
	{ RTP_DTMF_3,			       "DTMF Three 3" },
	{ RTP_DTMF_4,			       "DTMF Four 4" },
	{ RTP_DTMF_5,			       "DTMF Five 5" },
	{ RTP_DTMF_6,			       "DTMF Six 6" },
	{ RTP_DTMF_7,			       "DTMF Seven 7" },
	{ RTP_DTMF_8,			       "DTMF Eight 8" },
	{ RTP_DTMF_9,			       "DTMF Nine 9" },
	{ RTP_DTMF_STAR,		       "DTMF Star *" },
	{ RTP_DTMF_POUND,		       "DTMF Pound #" },
	{ RTP_DTMF_A,			       "DTMF A" },
	{ RTP_DTMF_B,			       "DTMF B" },
	{ RTP_DTMF_C,			       "DTMF C" },
	{ RTP_DTMF_D,			       "DTMF D" },
	{ RTP_DTMF_FLASH,		       "Flash" },
	{ RTP_ANS,			       "Fax ANS"},
	{ RTP_ANSREV,			       "Fax /ANS"},
	{ RTP_ANSAM,			       "Fax ANSam"},
	{ RTP_ANSAMREV,			       "Fax /ANSam"},
	{ RTP_CNG,			       "Fax CNG"},
	{ RTP_V21C1B0,			       "V.21 channel 1, 0 bit"},
	{ RTP_V21C1B1,			       "V.21 channel 1, 1 bit"},
	{ RTP_V21C2B0,			       "V.21 channel 2, 0 bit"},
	{ RTP_V21C2B1,			       "V.21 channel 2, 1 bit"},
	{ RTP_CRDI,			       "Fax CRdi"},
	{ RTP_CRDR,			       "Fax CRdr"},
	{ RTP_CRE,			       "Fax CRe"},
	{ RTP_ESI,			       "Fax ESi"},
	{ RTP_ESR,			       "Fax ESr"},
	{ RTP_MRDI,			       "Fax MRdi"},
	{ RTP_MRDR,			       "Fax MRdr"},
	{ RTP_MRE,			       "Fax MRe"},
	{ RTP_CT,			       "Fax CT"},
	{ RTP_OFFHOOK,			       "Off Hook"},
	{ RTP_ONHOOK,			       "On Hook"},
	{ RTP_DIALTONE,			       "Dial tone"},
	{ RTP_INTDT,			       "PABX internal dial tone"},
	{ RTP_SPCDT,			       "Special dial tone"},
	{ RTP_2NDDT,			       "Second dial tone"},
	{ RTP_RGTONE,			       "Ringing tone"},
	{ RTP_SPRGTONE,			       "Special ringing tone"},
	{ RTP_BUSYTONE,			       "Busy tone"},
	{ RTP_CNGTONE,			       "Congestion tone"},
	{ RTP_SPINFOTN,			       "Special information tone"},
	{ RTP_CMFTTONE,			       "Comfort tone"},
	{ RTP_HOLDTONE,			       "Hold tone"},
	{ RTP_RECTONE,			       "Record tone"},
	{ RTP_CLRWTTONE,		       "Caller waiting tone"},
	{ RTP_CWTONE,			       "Call waiting tone"},
	{ RTP_PAYTONE,			       "Pay tone"},
	{ RTP_POSINDTONE,		       "Positive indication tone"},
	{ RTP_NEGINDTONE,		       "Negative indication tone"},
	{ RTP_WARNTONE,			       "Warning tone"},
	{ RTP_INTRTONE,			       "Intrusion tone"},
	{ RTP_CALLCDTONE,		       "Calling card service tone"},
	{ RTP_PAYPHONE,			       "Payphone recognition tone"},
	{ RTP_CAS,			       "CPE alerting signal (CAS)"},
	{ RTP_OFFHKWARN,		       "Off-hook warning tone"},
	{ RTP_RING,			       "Ring"},
	{ RTP_ACCPTTONE,		       "Acceptance tone"},
	{ RTP_CONFIRMTN,		       "Confirmation tone"},
	{ RTP_DLTNRECALL,		       "Dial tone, recall"},
	{ RTP_END3WAYTN,		       "End of three party service tone"},
	{ RTP_FACTONE,			       "Facilities tone"},
	{ RTP_LNLOCKTN,			       "Line lockout tone"},
	{ RTP_NUMUNOBT,			       "Number unobtainable tone"},
	{ RTP_OFFERGTONE,		       "Offering tone"},
	{ RTP_PERMSIGTN,		       "Permanent signal tone"},
	{ RTP_PREEMPTTN,		       "Preemption tone"},
	{ RTP_QUETONE,			       "Queue tone"},
	{ RTP_REFUSALTN,		       "Refusal tone"},
	{ RTP_ROUTETONE,		       "Route tone"},
	{ RTP_VALIDTONE,		       "Valid tone"},
	{ RTP_WAITGTONE,		       "Waiting tone"},
	{ RTP_WARNEOPTN,		       "Warning tone (end of period)"},
	{ RTP_WARNPIPTN,		       "Warning Tone (PIP tone)"},
	{ RTP_MF0,			       "MF 0"},
	{ RTP_MF1,			       "MF 1"},
	{ RTP_MF2,			       "MF 2"},
	{ RTP_MF3,			       "MF 3"},
	{ RTP_MF4,			       "MF 4"},
	{ RTP_MF5,			       "MF 5"},
	{ RTP_MF6,			       "MF 6"},
	{ RTP_MF7,			       "MF 7"},
	{ RTP_MF8,			       "MF 8"},
	{ RTP_MF9,			       "MF 9"},
	{ RTP_K0,			       "MF K0 or KP (start-of-pulsing)"},
	{ RTP_K1,			       "MF K1"},
	{ RTP_K2,			       "MF K2"},
	{ RTP_S0,			       "MF S0 to ST (end-of-pulsing)"},
	{ RTP_S1,			       "MF S1"},
	{ RTP_S3,			       "MF S3"},
	{ RTP_WINK,			       "Wink"},
	{ RTP_WINKOFF,			       "Wink off"},
	{ RTP_INCSEIZ,			       "Incoming seizure"},
	{ RTP_SEIZURE,			       "Seizure"},
	{ RTP_UNSEIZE,			       "Unseize circuit"},
	{ RTP_COT,			       "Continuity test"},
	{ RTP_DEFCOT,			       "Default continuity tone"},
	{ RTP_COTTONE,			       "Continuity tone (single tone)"},
	{ RTP_COTSEND,			       "Continuity test send"},
	{ RTP_COTVERFD,			       "Continuity verified"},
	{ RTP_LOOPBACK,			       "Loopback"},
	{ RTP_MWATTTONE,		       "Old milliwatt tone (1000 Hz)"},
	{ RTP_NEWMWATTTN,		       "New milliwatt tone (1004 Hz)"},
	{ RTP_CISCO_NSE_FAX_PASSTHROUGH_IND,   "Cisco NSE: Shift to voiceband data mode"},
	{ RTP_CISCO_NSE_MODEM_PASSTHROUGH_IND, "Cisco NSE: Disable echo cancellation"},
	{ RTP_CISCO_NSE_VOICE_MODE_IND,        "Cisco NSE: Shift to voice mode"},
	{ RTP_CISCO_NSE_MODEM_RELAY_CAP_IND,   "Cisco NSE: Advertise Modem relay capability"},
	{ RTP_CISCO_NSE_FAX_RELAY_IND,         "Cisco NSE: Shift to fax relay mode"},
	{ RTP_CISCO_NSE_ACK,                   "Positive acknowledgement of Cisco NSE"},
	{ RTP_CISCO_NSE_NACK,                  "Negative acknowledgement of Cisco NSE"},
	{ RTP_CISCO_NSE_MODEM_RELAY_IND ,      "Cisco NSE: Shift to modem relay mode"},
	{ 0,               NULL },
};
value_string_ext rtp_event_type_values_ext = VALUE_STRING_EXT_INIT(rtp_event_type_values);

/* RTP Events fields defining a subtree */

static gint ett_rtp_events           = -1;

static dissector_handle_t rtp_events_handle;

static struct _rtp_event_info rtp_event_info;

static int
dissect_rtp_events( tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_ )
{
	proto_item   *ti;
	proto_tree   *rtp_events_tree;
	unsigned int  offset = 0;

	struct _rtp_conversation_info *p_conv_data;

	guint8 rtp_evt;
	guint8 octet;
	static const int * events[] = {
		&hf_rtp_events_end,
		&hf_rtp_events_reserved,
		&hf_rtp_events_volume,
		NULL
	};

	col_set_str(pinfo->cinfo, COL_PROTOCOL, "RTP EVENT");
	col_clear(pinfo->cinfo, COL_INFO);


	/* Get event fields */

	rtp_evt = tvb_get_guint8(tvb, offset );

	/* get tap info */
	rtp_event_info.info_rtp_evt = rtp_evt;

	p_conv_data = (struct _rtp_conversation_info *)p_get_proto_data(wmem_file_scope(), pinfo, proto_get_id_by_filter_name("rtp"), 0);
	if (p_conv_data)
		rtp_event_info.info_setup_frame_num = p_conv_data->frame_number;
	else
		rtp_event_info.info_setup_frame_num = 0;


	col_add_fstr( pinfo->cinfo, COL_INFO,
		"Payload type=RTP Event, %s",
		val_to_str_ext( rtp_evt, &rtp_event_type_values_ext, "Unknown (%u)" ));

	ti = proto_tree_add_item( tree, proto_rtp_events, tvb, offset, -1, ENC_NA );
	rtp_events_tree = proto_item_add_subtree( ti, ett_rtp_events );

	proto_tree_add_uint ( rtp_events_tree, hf_rtp_events_event, tvb, offset, 1, rtp_evt);
	offset++;
	octet = tvb_get_guint8(tvb, offset);
	proto_tree_add_bitmask_list(rtp_events_tree, tvb, offset, 1, events, ENC_NA);
	offset++;

	/* The duration field indicates the duration of the event or segment
	 * being reported, in timestamp units.
	 */
	rtp_event_info.info_duration = tvb_get_ntohs(tvb, offset);
	proto_tree_add_item ( rtp_events_tree, hf_rtp_events_duration, tvb, offset, 2, ENC_BIG_ENDIAN);

	/* set the end info for the tap */
	if (octet & 0x80)
	{
		rtp_event_info.info_end = TRUE;
	} else
	{
		rtp_event_info.info_end = FALSE;
	}

	/* Make end-of-event packets obvious in the info column */
	if ((octet & 0x80))
	{
		col_append_str(pinfo->cinfo, COL_INFO, " (end)");
	}

	tap_queue_packet(rtp_event_tap, pinfo, &rtp_event_info);
	return tvb_captured_length(tvb);
}


void
proto_register_rtp_events(void)
{

	module_t *rtp_events_module;

	static hf_register_info hf[] =
	{
		{
			&hf_rtp_events_event,
			{
				"Event ID",
				"rtpevent.event_id",
				FT_UINT8,
				BASE_DEC | BASE_EXT_STRING,
				&rtp_event_type_values_ext,
				0x0,
				NULL, HFILL
			}
		},
		{
			&hf_rtp_events_end,
			{
				"End of Event",
				"rtpevent.end_of_event",
				FT_BOOLEAN,
				8,
				NULL,
				0x80,
				NULL, HFILL
			}
		},
		{
			&hf_rtp_events_reserved,
			{
				"Reserved",
				"rtpevent.reserved",
				FT_BOOLEAN,
				8,
				NULL,
				0x40,
				NULL, HFILL
			}
		},
		{
			&hf_rtp_events_volume,
			{
				"Volume",
				"rtpevent.volume",
				FT_UINT8,
				BASE_DEC,
				NULL,
				0x3F,
				NULL, HFILL
			}
		},

		{
			&hf_rtp_events_duration,
			{
				"Event Duration",
				"rtpevent.duration",
				FT_UINT16,
				BASE_DEC,
				NULL,
				0x0,
				NULL, HFILL
			}
		},

	};

	static gint *ett[] =
	{
		&ett_rtp_events,
	};


	proto_rtp_events = proto_register_protocol("RFC 2833 RTP Event", "RTP Event", "rtpevent");
	proto_register_field_array(proto_rtp_events, hf, array_length(hf));
	proto_register_subtree_array(ett, array_length(ett));


	/* Register preferences */
	rtp_events_module = prefs_register_protocol (proto_rtp_events, proto_reg_handoff_rtp_events);
	prefs_register_uint_preference (rtp_events_module,
				    "event_payload_type_value", "Payload Type for RFC2833 RTP Events",
				    "This is the value of the Payload Type field"
				    " that specifies RTP Events", 10,
				    &rtp_event_payload_type_value);


	prefs_register_uint_preference (rtp_events_module,
				    "cisco_nse_payload_type_value", "Payload Type for Cisco Named Signaling Events",
				    "This is the value of the Payload Type field"
				    " that specifies Cisco Named Signaling Events", 10,
				    &cisco_nse_pt_value);

	rtp_events_handle = register_dissector("rtpevent", dissect_rtp_events, proto_rtp_events);
	rtp_event_tap = register_tap("rtpevent");
}



void
proto_reg_handoff_rtp_events(void)
{
	/* saved_payload_type_value is a temporary place to save */
	/* the value so we can properly reinitialize when the    */
	/* settings get changed.                                 */
	static guint	saved_payload_type_value;
	static guint	saved_cisco_nse_pt_value;
	static gboolean rtp_events_prefs_initialized = FALSE;

	if (!rtp_events_prefs_initialized) {
		dissector_add_string("rtp_dyn_payload_type", "telephone-event", rtp_events_handle);
		dissector_add_string("rtp_dyn_payload_type", "X-NSE", rtp_events_handle);
		rtp_events_prefs_initialized = TRUE;
	}
	else {
		dissector_delete_uint("rtp.pt", saved_payload_type_value, rtp_events_handle);
		dissector_delete_uint("rtp.pt", saved_cisco_nse_pt_value, rtp_events_handle);
	}

	saved_payload_type_value = rtp_event_payload_type_value;
	/* rtp_event_payload_type_value is set from preferences */
	saved_cisco_nse_pt_value = cisco_nse_pt_value;
	/* cisco_nse_pt_value is set from preferences */
	if(saved_payload_type_value != 0){
		dissector_add_uint("rtp.pt", saved_payload_type_value, rtp_events_handle);
		dissector_add_uint("rtp.pt", saved_cisco_nse_pt_value, rtp_events_handle);
	}
}

/*
 * Editor modelines  -  http://www.wireshark.org/tools/modelines.html
 *
 * Local variables:
 * c-basic-offset: 8
 * tab-width: 8
 * indent-tabs-mode: t
 * End:
 *
 * vi: set shiftwidth=8 tabstop=8 noexpandtab:
 * :indentSize=8:tabSize=8:noTabs=false:
 */