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/* packet-q931.c
* Routines for Q.931 frame disassembly
* Guy Harris <guy@alum.mit.edu>
*
* $Id: packet-q931.c,v 1.31 2001/07/03 04:56:45 guy Exp $
*
* Modified by Andreas Sikkema for possible use with H.323
*
* Ethereal - Network traffic analyzer
* By Gerald Combs <gerald@ethereal.com>
* Copyright 1998
*
* 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
#ifdef HAVE_SYS_TYPES_H
# include <sys/types.h>
#endif
#include <stdio.h>
#include <glib.h>
#include <string.h>
#include "packet.h"
#include "strutil.h"
#include "nlpid.h"
#include "packet-q931.h"
#include "packet-tpkt.h"
#ifdef H323
#include "packet-h225.h"
#endif
/* Q.931 references:
*
* http://www.acacia-net.com/Clarinet/Protocol/q9313svn.htm
* http://www.acacia-net.com/Clarinet/Protocol/q9311sc3.htm
* http://www.acacia-net.com/Clarinet/Protocol/q9317oz7.htm
* http://www.protocols.com/pbook/isdn.htm
* http://freesoft.org/CIE/Topics/126.htm
* http://noc.comstar.ru/miscdocs/ascend-faq-cause-codes.html
* http://www.andrews-arnold.co.uk/isdn/q931cause.html
* http://www.tulatelecom.ru/staff/german/DSSHelp/MessList/InfEl/InfElList.html
*/
static int proto_q931 = -1;
static int hf_q931_discriminator = -1;
static int hf_q931_call_ref_len = -1;
static int hf_q931_call_ref = -1;
static int hf_q931_message_type = -1;
static gint ett_q931 = -1;
static gint ett_q931_ie = -1;
/*
* Q.931 message types.
*/
#define Q931_ESCAPE 0x00
#define Q931_ALERTING 0x01
#define Q931_CALL_PROCEEDING 0x02
#define Q931_CONNECT 0x07
#define Q931_CONNECT_ACK 0x0F
#define Q931_PROGRESS 0x03
#define Q931_SETUP 0x05
#define Q931_SETUP_ACK 0x0D
#define Q931_HOLD 0x24
#define Q931_HOLD_ACK 0x28
#define Q931_HOLD_REJECT 0x30
#define Q931_RESUME 0x26
#define Q931_RESUME_ACK 0x2E
#define Q931_RESUME_REJECT 0x22
#define Q931_RETRIEVE 0x31
#define Q931_RETRIEVE_ACK 0x33
#define Q931_RETRIEVE_REJECT 0x37
#define Q931_SUSPEND 0x25
#define Q931_SUSPEND_ACK 0x2D
#define Q931_SUSPEND_REJECT 0x21
#define Q931_USER_INFORMATION 0x20
#define Q931_DISCONNECT 0x45
#define Q931_RELEASE 0x4D
#define Q931_RELEASE_COMPLETE 0x5A
#define Q931_RESTART 0x46
#define Q931_RESTART_ACK 0x4E
#define Q931_CONGESTION_CONTROL 0x79
#define Q931_FACILITY 0x62
#define Q931_INFORMATION 0x7B
#define Q931_NOTIFY 0x6E
#define Q931_REGISTER 0x64
#define Q931_SEGMENT 0x60
#define Q931_STATUS 0x7D
#define Q931_STATUS_ENQUIRY 0x75
static const value_string q931_message_type_vals[] = {
{ Q931_ESCAPE, "ESCAPE" },
{ Q931_ALERTING, "ALERTING" },
{ Q931_CALL_PROCEEDING, "CALL PROCEEDING" },
{ Q931_CONNECT, "CONNECT" },
{ Q931_CONNECT_ACK, "CONNECT ACKNOWLEDGE" },
{ Q931_PROGRESS, "PROGRESS" },
{ Q931_SETUP, "SETUP" },
{ Q931_SETUP_ACK, "SETUP ACKNOWLEDGE" },
{ Q931_HOLD, "HOLD" },
{ Q931_HOLD_ACK, "HOLD_ACKNOWLEDGE" },
{ Q931_HOLD_REJECT, "HOLD_REJECT" },
{ Q931_RESUME, "RESUME" },
{ Q931_RESUME_ACK, "RESUME ACKNOWLEDGE" },
{ Q931_RESUME_REJECT, "RESUME REJECT" },
{ Q931_RETRIEVE, "RETRIEVE" },
{ Q931_RETRIEVE_ACK, "RETRIEVE ACKNOWLEDGE" },
{ Q931_RETRIEVE_REJECT, "RETRIEVE REJECT" },
{ Q931_SUSPEND, "SUSPEND" },
{ Q931_SUSPEND_ACK, "SUSPEND ACKNOWLEDGE" },
{ Q931_SUSPEND_REJECT, "SUSPEND REJECT" },
{ Q931_USER_INFORMATION, "USER INFORMATION" },
{ Q931_DISCONNECT, "DISCONNECT" },
{ Q931_RELEASE, "RELEASE" },
{ Q931_RELEASE_COMPLETE, "RELEASE COMPLETE" },
{ Q931_RESTART, "RESTART" },
{ Q931_RESTART_ACK, "RESTART ACKNOWLEDGE" },
{ Q931_CONGESTION_CONTROL, "CONGESTION CONTROL" },
{ Q931_FACILITY, "FACILITY" },
{ Q931_INFORMATION, "INFORMATION" },
{ Q931_NOTIFY, "NOTIFY" },
{ Q931_REGISTER, "REGISTER" },
{ Q931_SEGMENT, "SEGMENT" },
{ Q931_STATUS, "STATUS" },
{ Q931_STATUS_ENQUIRY, "STATUS ENQUIRY" },
{ 0, NULL }
};
/*
* Information elements.
*/
/*
* Single-octet IEs.
*/
#define Q931_IE_SO_IDENTIFIER_MASK 0xf0 /* IE identifier mask */
#define Q931_IE_SO_IDENTIFIER_SHIFT 4 /* IE identifier shift */
#define Q931_IE_SO_IE_MASK 0x0F /* IE mask */
#define Q931_IE_SHIFT 0x90
#define Q931_IE_SHIFT_LOCKING 0x08 /* locking shift */
#define Q931_IE_SHIFT_CODESET 0x0F /* codeset */
#define Q931_IE_MORE_DATA_OR_SEND_COMP 0xA0 /* More Data or Sending Complete */
#define Q931_IE_MORE_DATA 0xA0
#define Q931_IE_SENDING_COMPLETE 0xA1
#define Q931_IE_CONGESTION_LEVEL 0xB0
#define Q931_IE_REPEAT_INDICATOR 0xD0
/*
* Variable-length IEs.
*/
#define Q931_IE_VL_EXTENSION 0x80 /* Extension flag */
/*
* Codeset 0 (default).
*/
#define Q931_IE_SEGMENTED_MESSAGE 0x00
#define Q931_IE_BEARER_CAPABILITY 0x04
#define Q931_IE_CAUSE 0x08
#define Q931_IE_CALL_IDENTITY 0x10
#define Q931_IE_CALL_STATE 0x14
#define Q931_IE_CHANNEL_IDENTIFICATION 0x18
#define Q931_IE_FACILITY 0x1C
#define Q931_IE_PROGRESS_INDICATOR 0x1E
#define Q931_IE_NETWORK_SPECIFIC_FACIL 0x20 /* Network Specific Facilities */
#define Q931_IE_NOTIFICATION_INDICATOR 0x27
#define Q931_IE_DISPLAY 0x28
#define Q931_IE_DATE_TIME 0x29
#define Q931_IE_KEYPAD_FACILITY 0x2C
#define Q931_IE_INFORMATION_REQUEST 0x32
#define Q931_IE_SIGNAL 0x34
#define Q931_IE_SWITCHHOOK 0x36
#define Q931_IE_FEATURE_ACTIVATION 0x38
#define Q931_IE_FEATURE_INDICATION 0x39
#define Q931_IE_ENDPOINT_IDENTIFIER 0x3B
#define Q931_IE_SERVICE_PROFILE_ID 0x3A
#define Q931_IE_INFORMATION_RATE 0x40
#define Q931_IE_E2E_TRANSIT_DELAY 0x42 /* End-to-end Transit Delay */
#define Q931_IE_TD_SELECTION_AND_INT 0x43 /* Transit Delay Selection and Indication */
#define Q931_IE_PL_BINARY_PARAMETERS 0x44 /* Packet layer binary parameters */
#define Q931_IE_PL_WINDOW_SIZE 0x45 /* Packet layer window size */
#define Q931_IE_PACKET_SIZE 0x46 /* Packet size */
#define Q931_IE_CUG 0x47 /* Closed user group */
#define Q931_IE_REVERSE_CHARGE_IND 0x4A /* Reverse charging indication */
#define Q931_IE_CALLING_PARTY_NUMBER 0x6C /* Calling Party Number */
#define Q931_IE_CALLING_PARTY_SUBADDR 0x6D /* Calling Party Subaddress */
#define Q931_IE_CALLED_PARTY_NUMBER 0x70 /* Called Party Number */
#define Q931_IE_CALLED_PARTY_SUBADDR 0x71 /* Called Party Subaddress */
#define Q931_IE_REDIRECTING_NUMBER 0x74
#define Q931_IE_REDIRECTION_NUMBER 0x76
#define Q931_IE_TRANSIT_NETWORK_SEL 0x78 /* Transit Network Selection */
#define Q931_IE_RESTART_INDICATOR 0x79
#define Q931_IE_LOW_LAYER_COMPAT 0x7C /* Low-Layer Compatibility */
#define Q931_IE_HIGH_LAYER_COMPAT 0x7D /* High-Layer Compatibility */
#define Q931_IE_USER_USER 0x7E /* User-User */
#define Q931_IE_ESCAPE 0x7F /* Escape for extension */
/*
* Codeset 0 ETSI.
*/
#define Q931_IE_CONNECTED_NUMBER 0x8C
#define Q931_IE_CONNECTED_SUBADDR 0x8D
/*
* Codeset 5 (National-specific) Belgium.
*/
#define Q931_IE_CHARGING_ADVICE 0x1A
/*
* Codeset 5 (National-specific) Bellcore National ISDN.
*/
#define Q931_IE_OPERATOR_SYSTEM_ACCESS 0x1D
/*
* Codeset 6 (Network-specific) Belgium.
*/
/* 0x1A is Charging Advice, as with Codeset 5 */
#define Q931_IE_REDIRECTING_NUMBER 0x74
/*
* Codeset 6 (Network-specific) FT-Numeris.
*/
/* 0x1D is User Capability */
/*
* Codeset 6 (Network-specific) Bellcore National ISDN.
*/
#define Q931_IE_REDIRECTING_SUBADDR 0x75 /* Redirecting Subaddress */
/* 0x76 is Redirection Number, but that's also Codeset 0 */
#define Q931_IE_CALL_APPEARANCE 0x7B
static const value_string q931_info_element_vals[] = {
{ Q931_IE_SEGMENTED_MESSAGE, "Segmented message" },
{ Q931_IE_BEARER_CAPABILITY, "Bearer capability" },
{ Q931_IE_CAUSE, "Cause" },
{ Q931_IE_CALL_IDENTITY, "Call identity" },
{ Q931_IE_CALL_STATE, "Call state" },
{ Q931_IE_CHANNEL_IDENTIFICATION, "Channel identification" },
{ Q931_IE_FACILITY, "Facility" },
{ Q931_IE_PROGRESS_INDICATOR, "Progress indicator" },
{ Q931_IE_NETWORK_SPECIFIC_FACIL, "Network specific facilities" },
{ Q931_IE_NOTIFICATION_INDICATOR, "Notification indicator" },
{ Q931_IE_DISPLAY, "Display" },
{ Q931_IE_DATE_TIME, "Date/Time" },
{ Q931_IE_KEYPAD_FACILITY, "Keypad facility" },
{ Q931_IE_INFORMATION_REQUEST, "Information request" },
{ Q931_IE_SIGNAL, "Signal" },
{ Q931_IE_SWITCHHOOK, "Switchhook" },
{ Q931_IE_FEATURE_ACTIVATION, "Feature activation" },
{ Q931_IE_FEATURE_INDICATION, "Feature Indication" },
{ Q931_IE_ENDPOINT_IDENTIFIER, "Endpoint identifier" },
{ Q931_IE_SERVICE_PROFILE_ID, "Service profile ID" },
{ Q931_IE_INFORMATION_RATE, "Information rate" },
{ Q931_IE_E2E_TRANSIT_DELAY, "End-to-end transit delay" },
{ Q931_IE_TD_SELECTION_AND_INT, "Transit delay selection and indication" },
{ Q931_IE_PL_BINARY_PARAMETERS, "Packet layer binary parameters" },
{ Q931_IE_PL_WINDOW_SIZE, "Packet layer window size" },
{ Q931_IE_PACKET_SIZE, "Packet size" },
{ Q931_IE_CUG, "Closed user group" },
{ Q931_IE_REVERSE_CHARGE_IND, "Reverse charging indication" },
{ Q931_IE_CALLING_PARTY_NUMBER, "Calling party number" },
{ Q931_IE_CALLING_PARTY_SUBADDR, "Calling party subaddress" },
{ Q931_IE_CALLED_PARTY_NUMBER, "Called party number" },
{ Q931_IE_CALLED_PARTY_SUBADDR, "Called party subaddress" },
{ Q931_IE_REDIRECTING_NUMBER, "Redirecting number" },
{ Q931_IE_REDIRECTION_NUMBER, "Redirection number" },
{ Q931_IE_TRANSIT_NETWORK_SEL, "Transit network selection" },
{ Q931_IE_RESTART_INDICATOR, "Restart indicator" },
{ Q931_IE_LOW_LAYER_COMPAT, "Low-layer compatibility" },
{ Q931_IE_HIGH_LAYER_COMPAT, "High-layer compatibility" },
{ Q931_IE_USER_USER, "User-user" },
{ Q931_IE_ESCAPE, "Escape" },
{ Q931_IE_CONNECTED_NUMBER, "Connected number" },
{ Q931_IE_CONNECTED_SUBADDR, "Connected subaddress" },
{ Q931_IE_CHARGING_ADVICE, "Charging advice" },
{ Q931_IE_OPERATOR_SYSTEM_ACCESS, "Operator system access" },
{ Q931_IE_REDIRECTING_NUMBER, "Redirecting number" },
{ Q931_IE_REDIRECTING_SUBADDR, "Redirecting subaddress" },
{ Q931_IE_CALL_APPEARANCE, "Call appearance" },
{ 0, NULL }
};
static const value_string q931_congestion_level_vals[] = {
{ 0x0, "Receiver ready" },
{ 0xF, "Receiver not ready" },
{ 0, NULL }
};
static const value_string q931_repeat_indication_vals[] = {
{ 0x2, "Prioritized list" },
{ 0, NULL }
};
/*
* ITU-standardized coding.
*/
#define Q931_ITU_STANDARDIZED_CODING 0x00
/*
* Dissect a Segmented message information element.
*/
static void
dissect_q931_segmented_message_ie(tvbuff_t *tvb, int offset, int len,
proto_tree *tree)
{
if (len != 2) {
proto_tree_add_text(tree, tvb, offset, len,
"Segmented message: length is %d, should be 2\n", len);
return;
}
if (tvb_get_guint8(tvb, offset) & 0x80) {
proto_tree_add_text(tree, tvb, offset, 1,
"First segment: %u segments remaining",
tvb_get_guint8(tvb, offset) & 0x7F);
} else {
proto_tree_add_text(tree, tvb, offset, 1,
"Not first segment: %u segments remaining",
tvb_get_guint8(tvb, offset) & 0x7F);
}
proto_tree_add_text(tree, tvb, offset + 1, 1,
"Segmented message type: %u\n", tvb_get_guint8(tvb, offset + 1));
}
/*
* Dissect a Bearer capability or Low-layer compatibility information element.
*/
static const value_string q931_bc_coding_standard_vals[] = {
{ 0x00, "ITU-T standardized coding" },
{ 0x20, "ISO/IEC standard" },
{ 0x40, "National standard" },
{ 0x60, "Standard defined for this particular network" },
{ 0, NULL }
};
static const value_string q931_information_transfer_capability_vals[] = {
{ 0x00, "Speech" },
{ 0x08, "Unrestricted digital information" },
{ 0x09, "Restricted digital information" },
{ 0x10, "3.1 kHz audio" },
{ 0x11, "Unrestricted digital information with tones/announcements" },
{ 0x18, "Video" },
{ 0, NULL }
};
static const value_string q931_transfer_mode_vals[] = {
{ 0x00, "Circuit mode" },
{ 0x40, "Packet mode" },
{ 0, NULL }
};
#define Q931_IT_RATE_MULTIRATE 0x18
static const value_string q931_information_transfer_rate_vals[] = {
{ 0x00, "Packet mode" },
{ 0x10, "64 kbit/s" },
{ 0x11, "2 x 64 kbit/s" },
{ 0x13, "384 kbit/s" },
{ 0x15, "1536 kbit/s" },
{ 0x17, "1920 kbit/s" },
{ Q931_IT_RATE_MULTIRATE, "Multirate (64 kbit/s base rate)" },
{ 0, NULL }
};
static const value_string q931_uil1_vals[] = {
{ 0x01, "V.110/I.460/X.30 rate adaption" },
{ 0x02, "Recommendation G.711 u-law" },
{ 0x03, "Recommendation G.711 A-law" },
{ 0x04, "Recommendation G.721 32 kbit/s ADPCM and Recommendation I.460" },
{ 0x05, "Recommendation H.221 and H.242" },
{ 0x06, "Recommendation H.223 and H.245" },
{ 0x07, "Non-ITU-T-standardized rate adaption" },
{ 0x08, "V.120 rate adaption" },
{ 0x09, "X.31 HDLC flag stuffing" },
{ 0, NULL },
};
static const value_string q931_l1_user_rate_vals[] = {
{ 0x00, "Rate indicated by E-bits" },
{ 0x01, "0.6 kbit/s" },
{ 0x02, "1.2 kbit/s" },
{ 0x03, "2.4 kbit/s" },
{ 0x04, "3.6 kbit/s" },
{ 0x05, "4.8 kbit/s" },
{ 0x06, "7.2 kbit/s" },
{ 0x07, "8 kbit/s" },
{ 0x08, "9.6 kbit/s" },
{ 0x09, "14.4 kbit/s" },
{ 0x0A, "16 kbit/s" },
{ 0x0B, "19.2 kbit/s" },
{ 0x0C, "32 kbit/s" },
{ 0x0E, "48 kbit/s" },
{ 0x0F, "56 kbit/s" },
{ 0x10, "64 kbit/s "},
{ 0x15, "0.1345 kbit/s" },
{ 0x16, "0.100 kbit/s" },
{ 0x17, "0.075/1.2 kbit/s" },
{ 0x18, "1.2/0.075 kbit/s" },
{ 0x19, "0.050 kbit/s" },
{ 0x1A, "0.075 kbit/s" },
{ 0x1B, "0.110 kbit/s" },
{ 0x1C, "0.150 kbit/s" },
{ 0x1D, "0.200 kbit/s" },
{ 0x1E, "0.300 kbit/s" },
{ 0x1F, "12 kbit/s" },
{ 0, NULL }
};
static const value_string q931_l1_intermediate_rate_vals[] = {
{ 0x20, "8 kbit/s" },
{ 0x40, "16 kbit/s" },
{ 0x60, "32 kbit/s" },
{ 0, NULL }
};
static const value_string q931_l1_stop_bits_vals[] = {
{ 0x20, "1" },
{ 0x40, "1.5" },
{ 0x60, "2" },
{ 0, NULL }
};
static const value_string q931_l1_data_bits_vals[] = {
{ 0x08, "5" },
{ 0x10, "7" },
{ 0x18, "8" },
{ 0, NULL }
};
static const value_string q931_l1_parity_vals[] = {
{ 0x00, "Odd" },
{ 0x02, "Even" },
{ 0x03, "None" },
{ 0x04, "Forced to 0" },
{ 0x05, "Forced to 1" },
{ 0, NULL }
};
static const value_string q931_l1_modem_type_vals[] = {
{ 0x11, "V.21" },
{ 0x12, "V.22" },
{ 0x13, "V.22 bis" },
{ 0x14, "V.23" },
{ 0x15, "V.26" },
{ 0x16, "V.26 bis" },
{ 0x17, "V.26 ter" },
{ 0x18, "V.27" },
{ 0x19, "V.27 bis" },
{ 0x1A, "V.27 ter" },
{ 0x1B, "V.29" },
{ 0x1C, "V.32" },
{ 0x1E, "V.34" },
{ 0, NULL }
};
#define Q931_UIL2_USER_SPEC 0x10
static const value_string q931_uil2_vals[] = {
{ 0x01, "Basic mode ISO 1745" },
{ 0x02, "Q.921/I.441" }, /* LAPD */
{ 0x06, "X.25, link layer" }, /* LAPB */
{ 0x07, "X.25 multilink" }, /* or 0x0F? */
{ 0x08, "T.71 Extended LAPB" },
{ 0x09, "HDLC ARM" },
{ 0x0A, "HDLC NRM" },
{ 0x0B, "HDLC ABM" },
{ 0x0C, "ISO 8802/2 LLC" },
{ 0x0D, "X.75 Single Link Procedure" },
{ 0x0E, "Q.922" },
{ 0x0F, "Core aspects of Q.922" },
{ Q931_UIL2_USER_SPEC, "User-specified" },
{ 0x11, "ISO 7776 DTE-DTE operation" },
{ 0, NULL }
};
static const value_string q931_mode_vals[] = {
{ 0x20, "Normal mode" },
{ 0x40, "Extended mode" },
{ 0, NULL }
};
#define Q931_UIL3_X25_PL 0x06
#define Q931_UIL3_ISO_8208 0x07 /* X.25-based */
#define Q931_UIL3_X223 0x08 /* X.25-based */
#define Q931_UIL3_TR_9577 0x0B
#define Q931_UIL3_USER_SPEC 0x10
static const value_string q931_uil3_vals[] = {
{ 0x02, "Q.931/I.451" },
{ Q931_UIL3_X25_PL, "X.25, packet layer" },
{ Q931_UIL3_ISO_8208, "ISO/IEC 8208" },
{ Q931_UIL3_X223, "X.223/ISO 8878" },
{ 0x09, "ISO/IEC 8473" },
{ 0x0A, "T.70" },
{ Q931_UIL3_TR_9577, "ISO/IEC TR 9577" },
{ Q931_UIL3_USER_SPEC, "User-specified" },
{ 0, NULL }
};
static void
dissect_q931_protocol_discriminator(tvbuff_t *tvb, int offset, proto_tree *tree)
{
unsigned int discriminator = tvb_get_guint8(tvb, offset);
if (discriminator == NLPID_Q_931) {
proto_tree_add_uint_format(tree, hf_q931_discriminator,
tvb, offset, 1, discriminator,
"Protocol discriminator: Q.931");
} else if (discriminator == NLPID_Q_2931) {
proto_tree_add_uint_format(tree, hf_q931_discriminator,
tvb, offset, 1, discriminator,
"Protocol discriminator: Q.2931");
} else if ((discriminator >= 16 && discriminator < 63)
|| ((discriminator >= 80) && (discriminator < 254))) {
proto_tree_add_uint_format(tree, hf_q931_discriminator,
tvb, offset, 1, discriminator,
"Protocol discriminator: Network layer or layer 3 protocol (0x%02X)",
discriminator);
} else if (discriminator >= 64 && discriminator <= 79) {
proto_tree_add_uint_format(tree, hf_q931_discriminator,
tvb, offset, 1, discriminator,
"Protocol discriminator: National use (0x%02X)",
discriminator);
} else {
proto_tree_add_uint_format(tree, hf_q931_discriminator,
tvb, offset, 1, discriminator,
"Protocol discriminator: Reserved (0x%02X)",
discriminator);
}
}
void
dissect_q931_bearer_capability_ie(tvbuff_t *tvb, int offset, int len,
proto_tree *tree)
{
guint8 octet;
guint8 coding_standard;
guint8 it_rate;
guint8 modem_type;
guint8 uil2_protocol;
guint8 uil3_protocol;
guint8 add_l3_info;
if (len == 0)
return;
octet = tvb_get_guint8(tvb, offset);
coding_standard = octet & 0x60;
proto_tree_add_text(tree, tvb, offset, 1,
"Coding standard: %s",
val_to_str(coding_standard, q931_bc_coding_standard_vals, NULL));
if (coding_standard != Q931_ITU_STANDARDIZED_CODING) {
/*
* We don't know how the bearer capability is encoded,
* so just dump it as data and be done with it.
*/
proto_tree_add_text(tree, tvb, offset,
len, "Data: %s",
tvb_bytes_to_str(tvb, offset, len));
return;
}
proto_tree_add_text(tree, tvb, offset, 1,
"Information transfer capability: %s",
val_to_str(octet & 0x1F, q931_information_transfer_capability_vals,
"Unknown (0x%02X)"));
offset += 1;
len -= 1;
/*
* XXX - only in Low-layer compatibility information element.
*/
if (!(octet & Q931_IE_VL_EXTENSION)) {
if (len == 0)
return;
octet = tvb_get_guint8(tvb, offset);
proto_tree_add_text(tree, tvb, offset, 1,
"Out-band negotiation %spossible",
(octet & 0x40) ? "" : "not ");
offset += 1;
len -= 1;
}
if (len == 0)
return;
octet = tvb_get_guint8(tvb, offset);
proto_tree_add_text(tree, tvb, offset, 1,
"Transfer mode: %s",
val_to_str(octet & 0x60, q931_transfer_mode_vals,
"Unknown (0x%02X)"));
it_rate = octet & 0x1F;
proto_tree_add_text(tree, tvb, offset, 1,
"Information transfer rate: %s",
val_to_str(it_rate, q931_information_transfer_rate_vals,
"Unknown (0x%02X)"));
offset += 1;
len -= 1;
if (it_rate == Q931_IT_RATE_MULTIRATE) {
if (len == 0)
return;
proto_tree_add_text(tree, tvb, offset, 1, "Rate multiplier: %u", tvb_get_guint8(tvb, offset));
offset += 1;
len -= 1;
}
if (len == 0)
return;
octet = tvb_get_guint8(tvb, offset);
if ((octet & 0x60) == 0x20) {
/*
* Layer 1 information.
*/
proto_tree_add_text(tree, tvb, offset, 1,
"User information layer 1 protocol: %s",
val_to_str(octet & 0x1F, q931_uil1_vals,
"Unknown (0x%02X)"));
offset += 1;
len -= 1;
if (octet & Q931_IE_VL_EXTENSION)
goto l1_done;
if (len == 0)
return;
octet = tvb_get_guint8(tvb, offset);
proto_tree_add_text(tree, tvb, offset, 1,
"Layer 1 is %s",
(octet & 0x40) ? "Asynchronous" : "Synchronous");
proto_tree_add_text(tree, tvb, offset, 1,
"Layer 1 in-band negotiation is %spossible",
(octet & 0x20) ? "" : "not ");
proto_tree_add_text(tree, tvb, offset, 1,
"User rate: %s",
val_to_str(octet & 0x1F, q931_l1_user_rate_vals,
"Unknown (0x%02X)"));
offset += 1;
len -= 1;
if (octet & Q931_IE_VL_EXTENSION)
goto l1_done;
if (len == 0)
return;
octet = tvb_get_guint8(tvb, offset);
proto_tree_add_text(tree, tvb, offset, 1,
"Intermediate rate: %s",
val_to_str(octet & 0x60, q931_l1_intermediate_rate_vals,
"Unknown (0x%X)"));
proto_tree_add_text(tree, tvb, offset, 1,
"%s to send data with network independent clock",
(octet & 0x10) ? "Required" : "Not required");
proto_tree_add_text(tree, tvb, offset, 1,
"%s accept data with network independent clock",
(octet & 0x08) ? "Can" : "Cannot");
proto_tree_add_text(tree, tvb, offset, 1,
"%s to send data with flow control mechanism",
(octet & 0x04) ? "Required" : "Not required");
proto_tree_add_text(tree, tvb, offset, 1,
"%s accept data with flow control mechanism",
(octet & 0x02) ? "Can" : "Cannot");
offset += 1;
len -= 1;
if (octet & Q931_IE_VL_EXTENSION)
goto l1_done;
if (len == 0)
return;
octet = tvb_get_guint8(tvb, offset);
proto_tree_add_text(tree, tvb, offset, 1,
"Rate adaption header %sincluded",
(octet & 0x40) ? "" : "not ");
proto_tree_add_text(tree, tvb, offset, 1,
"Multiple frame establishment %ssupported",
(octet & 0x20) ? "" : "not ");
proto_tree_add_text(tree, tvb, offset, 1,
"%s mode of operation",
(octet & 0x10) ? "Protocol sensitive" : "Bit transparent");
proto_tree_add_text(tree, tvb, offset, 1,
(octet & 0x08) ?
"Full protocol negotiation" : "LLI = 256 only");
proto_tree_add_text(tree, tvb, offset, 1,
"Message originator is %s",
(octet & 0x04) ? "Assignor only" : "Default assignee");
proto_tree_add_text(tree, tvb, offset, 1,
"Negotiation is done %s",
(octet & 0x02) ? "in-band" : "out-of-band");
offset += 1;
len -= 1;
if (octet & Q931_IE_VL_EXTENSION)
goto l1_done;
if (len == 0)
return;
octet = tvb_get_guint8(tvb, offset);
proto_tree_add_text(tree, tvb, offset, 1,
"Stop bits: %s",
val_to_str(octet & 0x60, q931_l1_stop_bits_vals,
"Unknown (0x%X)"));
proto_tree_add_text(tree, tvb, offset, 1,
"Data bits: %s",
val_to_str(octet & 0x18, q931_l1_data_bits_vals,
"Unknown (0x%X)"));
proto_tree_add_text(tree, tvb, offset, 1,
"Parity: %s",
val_to_str(octet & 0x08, q931_l1_parity_vals,
"Unknown (0x%X)"));
if (octet & Q931_IE_VL_EXTENSION)
goto l1_done;
if (len == 0)
return;
octet = tvb_get_guint8(tvb, offset);
proto_tree_add_text(tree, tvb, offset, 1,
"%s duplex",
(octet & 0x40) ? "Full" : "Half");
modem_type = octet & 0x3F;
if (modem_type <= 0x5 ||
(modem_type >= 0x20 && modem_type <= 0x2F)) {
proto_tree_add_text(tree, tvb, offset, 1,
"Modem type: National use 0x%02X", modem_type);
} else if (modem_type >= 0x30) {
proto_tree_add_text(tree, tvb, offset, 1,
"Modem type: User specified 0x%02X", modem_type);
} else {
proto_tree_add_text(tree, tvb, offset, 1,
"Modem type: %s",
val_to_str(modem_type, q931_l1_modem_type_vals,
"Unknown (0x%02X)"));
}
offset += 1;
len -= 1;
}
l1_done:
;
if (len == 0)
return;
octet = tvb_get_guint8(tvb, offset);
if ((octet & 0x60) == 0x40) {
/*
* Layer 2 information.
*/
uil2_protocol = octet & 0x1F;
proto_tree_add_text(tree, tvb, offset, 1,
"User information layer 2 protocol: %s",
val_to_str(uil2_protocol, q931_uil2_vals,
"Unknown (0x%02X)"));
offset += 1;
len -= 1;
/*
* XXX - only in Low-layer compatibility information element.
*/
if (octet & Q931_IE_VL_EXTENSION)
goto l2_done;
if (len == 0)
return;
octet = tvb_get_guint8(tvb, offset);
if (uil2_protocol == Q931_UIL2_USER_SPEC) {
proto_tree_add_text(tree, tvb, offset, 1,
"User-specified layer 2 protocol information: 0x%02X",
octet & 0x7F);
} else {
proto_tree_add_text(tree, tvb, offset, 1,
"Mode: %s",
val_to_str(octet & 0x60, q931_mode_vals,
"Unknown (0x%02X)"));
}
offset += 1;
len -= 1;
if (octet & Q931_IE_VL_EXTENSION)
goto l2_done;
if (len == 0)
return;
octet = tvb_get_guint8(tvb, offset);
proto_tree_add_text(tree, tvb, offset, 1,
"Window size: %u k", octet & 0x7F);
offset += 1;
len -= 1;
}
l2_done:
;
if (len == 0)
return;
octet = tvb_get_guint8(tvb, offset);
if ((octet & 0x60) == 0x60) {
/*
* Layer 3 information.
*/
uil3_protocol = octet & 0x1F;
proto_tree_add_text(tree, tvb, offset, 1,
"User information layer 3 protocol: %s",
val_to_str(uil3_protocol, q931_uil3_vals,
"Unknown (0x%02X)"));
offset += 1;
len -= 1;
/*
* XXX - only in Low-layer compatibility information element.
*/
if (octet & Q931_IE_VL_EXTENSION)
goto l3_done;
if (len == 0)
return;
octet = tvb_get_guint8(tvb, offset);
switch (uil3_protocol) {
case Q931_UIL3_X25_PL:
case Q931_UIL3_ISO_8208:
case Q931_UIL3_X223:
proto_tree_add_text(tree, tvb, offset, 1,
"Mode: %s",
val_to_str(octet & 0x60, q931_mode_vals,
"Unknown (0x%02X)"));
offset += 1;
len -= 1;
if (octet & Q931_IE_VL_EXTENSION)
goto l3_done;
if (len == 0)
return;
octet = tvb_get_guint8(tvb, offset);
proto_tree_add_text(tree, tvb, offset, 1,
"Default packet size: %u", octet & 0x0F);
offset += 1;
len -= 1;
if (octet & Q931_IE_VL_EXTENSION)
goto l3_done;
if (len == 0)
return;
octet = tvb_get_guint8(tvb, offset);
proto_tree_add_text(tree, tvb, offset, 1,
"Packet window size: %u", octet & 0x7F);
offset += 1;
len -= 1;
break;
case Q931_UIL3_USER_SPEC:
proto_tree_add_text(tree, tvb, offset, 1,
"Default packet size: %u octets",
1 << (octet & 0x0F));
offset += 1;
len -= 1;
break;
case Q931_UIL3_TR_9577:
add_l3_info = (octet & 0x0F) << 4;
if (octet & Q931_IE_VL_EXTENSION)
goto l3_done;
if (len == 0)
return;
octet = tvb_get_guint8(tvb, offset + 1);
add_l3_info |= (octet & 0x0F);
proto_tree_add_text(tree, tvb, offset, 2,
"Additional layer 3 protocol information: %s",
val_to_str(add_l3_info, nlpid_vals,
"Unknown (0x%02X)"));
offset += 2;
len -= 2;
break;
}
}
l3_done:
;
}
/*
* Dissect a Cause information element.
*/
static const value_string q931_cause_coding_standard_vals[] = {
{ 0x00, "ITU-T standardized coding" },
{ 0x20, "ISO/IEC standard" },
{ 0x40, "National standard" },
{ 0x60, "Standard specific to identified location" },
{ 0, NULL }
};
static const value_string q931_cause_location_vals[] = {
{ 0x00, "User (U)" },
{ 0x01, "Private network serving the local user (LPN)" },
{ 0x02, "Public network serving the local user (LN)" },
{ 0x03, "Transit network (TN)" },
{ 0x04, "Public network serving the remote user (RLN)" },
{ 0x05, "Private network serving the remote user (RPN)" },
{ 0x07, "International network (INTL)" },
{ 0x0A, "Network beyond interworking point (BI)" },
{ 0, NULL }
};
static const value_string q931_cause_recommendation_vals[] = {
{ 0x00, "Q.931" },
{ 0x03, "X.21" },
{ 0x04, "X.25" },
{ 0x05, "Q.1031/Q.1051" },
{ 0, NULL }
};
/*
* Cause codes for Cause.
*/
static const value_string q931_cause_code_vals[] = {
{ 0x00, "Valid cause code not yet received" },
{ 0x01, "Unallocated (unassigned) number" },
{ 0x02, "No route to specified transit network" },
{ 0x03, "No route to destination" },
{ 0x04, "Send special information tone" },
{ 0x05, "Misdialled trunk prefix" },
{ 0x06, "Channel unacceptable" },
{ 0x07, "Call awarded and being delivered in an established channel" },
{ 0x08, "Prefix 0 dialed but not allowed" },
{ 0x09, "Prefix 1 dialed but not allowed" },
{ 0x0A, "Prefix 1 dialed but not required" },
{ 0x0B, "More digits received than allowed, call is proceeding" },
{ 0x10, "Normal call clearing" },
{ 0x11, "User busy" },
{ 0x12, "No user responding" },
{ 0x13, "No answer from user (user alerted)" },
{ 0x14, "Subscriber absent" },
{ 0x15, "Call rejected" },
{ 0x16, "Number changed" },
{ 0x17, "Reverse charging rejected" },
{ 0x18, "Call suspended" },
{ 0x19, "Call resumed" },
{ 0x1A, "Non-selected user clearing" },
{ 0x1B, "Destination out of order" },
{ 0x1C, "Invalid number format (incomplete number)" },
{ 0x1D, "Facility rejected" },
{ 0x1E, "Response to STATUS ENQUIRY" },
{ 0x1F, "Normal unspecified" },
{ 0x21, "Circuit out of order" },
{ 0x22, "No circuit/channel available" },
{ 0x23, "Destination unattainable" },
{ 0x25, "Degraded service" },
{ 0x26, "Network out of order" },
{ 0x27, "Transit delay range cannot be achieved" },
{ 0x28, "Throughput range cannot be achieved" },
{ 0x29, "Temporary failure" },
{ 0x2A, "Switching equipment congestion" },
{ 0x2B, "Access information discarded" },
{ 0x2C, "Requested circuit/channel not available" },
{ 0x2D, "Pre-empted" },
{ 0x2E, "Precedence call blocked" },
{ 0x2F, "Resources unavailable, unspecified" },
{ 0x31, "Quality of service unavailable" },
{ 0x32, "Requested facility not subscribed" },
{ 0x33, "Reverse charging not allowed" },
{ 0x34, "Outgoing calls barred" },
{ 0x35, "Outgoing calls barred within CUG" },
{ 0x36, "Incoming calls barred" },
{ 0x37, "Incoming calls barred within CUG" },
{ 0x38, "Call waiting not subscribed" },
{ 0x39, "Bearer capability not authorized" },
{ 0x3A, "Bearer capability not presently available" },
{ 0x3E, "Inconsistency in designated outgoing access information and subscriber class" },
{ 0x3F, "Service or option not available, unspecified" },
{ 0x41, "Bearer capability not implemented" },
{ 0x42, "Channel type not implemented" },
{ 0x43, "Transit network selection not implemented" },
{ 0x44, "Message not implemented" },
{ 0x45, "Requested facility not implemented" },
{ 0x46, "Only restricted digital information bearer capability is available" },
{ 0x4F, "Service or option not implemented, unspecified" },
{ 0x51, "Invalid call reference value" },
{ 0x52, "Identified channel does not exist" },
{ 0x53, "Call identity does not exist for suspended call" },
{ 0x54, "Call identity in use" },
{ 0x55, "No call suspended" },
{ 0x56, "Call having the requested call identity has been cleared" },
{ 0x57, "Called user not member of CUG" },
{ 0x58, "Incompatible destination" },
{ 0x59, "Non-existent abbreviated address entry" },
{ 0x5A, "Destination address missing, and direct call not subscribed" },
{ 0x5B, "Invalid transit network selection (national use)" },
{ 0x5C, "Invalid facility parameter" },
{ 0x5D, "Mandatory information element is missing" },
{ 0x5F, "Invalid message, unspecified" },
{ 0x60, "Mandatory information element is missing" },
{ 0x61, "Message type non-existent or not implemented" },
{ 0x62, "Message not compatible with call state or message type non-existent or not implemented" },
{ 0x63, "Information element nonexistant or not implemented" },
{ 0x64, "Invalid information element contents" },
{ 0x65, "Message not compatible with call state" },
{ 0x66, "Recovery on timer expiry" },
{ 0x67, "Parameter non-existent or not implemented - passed on" },
{ 0x6E, "Message with unrecognized parameter discarded" },
{ 0x6F, "Protocol error, unspecified" },
{ 0x7F, "Internetworking, unspecified" },
{ 0, NULL }
};
static void
dissect_q931_cause_ie(tvbuff_t *tvb, int offset, int len,
proto_tree *tree)
{
guint8 octet;
guint8 coding_standard;
if (len == 0)
return;
octet = tvb_get_guint8(tvb, offset);
coding_standard = octet & 0x60;
proto_tree_add_text(tree, tvb, offset, 1,
"Coding standard: %s",
val_to_str(coding_standard, q931_cause_coding_standard_vals, NULL));
if (coding_standard != Q931_ITU_STANDARDIZED_CODING) {
/*
* We don't know how the cause is encoded,
* so just dump it as data and be done with it.
*/
proto_tree_add_text(tree, tvb, offset,
len, "Data: %s",
tvb_bytes_to_str(tvb, offset, len));
return;
}
proto_tree_add_text(tree, tvb, offset, 1,
"Location: %s",
val_to_str(octet & 0x0F, q931_cause_location_vals,
"Unknown (0x%X)"));
offset += 1;
len -= 1;
if (!(octet & Q931_IE_VL_EXTENSION)) {
if (len == 0)
return;
octet = tvb_get_guint8(tvb, offset);
proto_tree_add_text(tree, tvb, offset, 1,
"Recommendation: %s",
val_to_str(octet & 0x7F, q931_cause_recommendation_vals,
"Unknown (0x%02X)"));
offset += 1;
len -= 1;
}
if (len == 0)
return;
octet = tvb_get_guint8(tvb, offset);
proto_tree_add_text(tree, tvb, offset, 1,
"Cause value: %s",
val_to_str(octet & 0x7F, q931_cause_code_vals,
"Unknown (0x%02X)"));
offset += 1;
len -= 1;
if (len == 0)
return;
proto_tree_add_text(tree, tvb, offset, len,
"Diagnostics: %s",
tvb_bytes_to_str(tvb, offset, len));
}
/*
* Dissect a Call state information element.
*/
static const value_string q931_coding_standard_vals[] = {
{ 0x00, "ITU-T standardized coding" },
{ 0x20, "ISO/IEC standard" },
{ 0x40, "National standard" },
{ 0x60, "Standard defined for the network" },
{ 0, NULL }
};
static const value_string q931_call_state_vals[] = {
{ 0x00, "Null" },
{ 0x01, "Call initiated" },
{ 0x02, "Overlap sending" },
{ 0x03, "Outgoing call proceeding" },
{ 0x04, "Call delivered" },
{ 0x06, "Call present" },
{ 0x07, "Call received" },
{ 0x08, "Connect request" },
{ 0x09, "Incoming call proceeding" },
{ 0x0A, "Active" },
{ 0x0B, "Disconnect request" },
{ 0x0C, "Disconnect indication" },
{ 0x0F, "Suspend request" },
{ 0x12, "Resume request" },
{ 0x13, "Release request" },
{ 0x16, "Call abort"},
{ 0x19, "Overlap receiving" },
{ 0x3D, "Restart request" },
{ 0x3E, "Restart" },
{ 0, NULL }
};
static void
dissect_q931_call_state_ie(tvbuff_t *tvb, int offset, int len,
proto_tree *tree)
{
guint8 octet;
guint8 coding_standard;
if (len == 0)
return;
octet = tvb_get_guint8(tvb, offset);
coding_standard = octet & 0x60;
proto_tree_add_text(tree, tvb, offset, 1,
"Coding standard: %s",
val_to_str(coding_standard, q931_coding_standard_vals, NULL));
if (coding_standard != Q931_ITU_STANDARDIZED_CODING) {
/*
* We don't know how the call state is encoded,
* so just dump it as data and be done with it.
*/
proto_tree_add_text(tree, tvb, offset,
len, "Data: %s",
tvb_bytes_to_str(tvb, offset, len));
return;
}
proto_tree_add_text(tree, tvb, offset, 1,
"Call state: %s",
val_to_str(octet & 0x3F, q931_call_state_vals,
"Unknown (0x%02X)"));
}
/*
* Dissect a Channel identification information element.
*/
#define Q931_INTERFACE_IDENTIFIED 0x40
#define Q931_NOT_BASIC_CHANNEL 0x20
static const value_string q931_basic_channel_selection_vals[] = {
{ 0x00, "No channel" },
{ 0x01, "B1 channel" },
{ 0x02, "B2 channel" },
{ 0x03, "Any channel" },
{ 0, NULL }
};
static const value_string q931_not_basic_channel_selection_vals[] = {
{ 0x00, "No channel" },
{ 0x01, "Channel indicated in following octets" },
{ 0x03, "Any channel" },
{ 0, NULL }
};
#define Q931_IS_SLOT_MAP 0x10
static const value_string q931_element_type_vals[] = {
{ 0x03, "B-channel units" },
{ 0x06, "H0-channel units" },
{ 0x08, "H11-channel units" },
{ 0x09, "H12-channel units" },
{ 0, NULL }
};
static void
dissect_q931_channel_identification_ie(tvbuff_t *tvb, int offset, int len,
proto_tree *tree)
{
guint8 octet;
int identifier_offset;
int identifier_len;
guint8 coding_standard;
if (len == 0)
return;
octet = tvb_get_guint8(tvb, offset);
proto_tree_add_text(tree, tvb, offset, 1,
"Interface %s identified",
(octet & Q931_INTERFACE_IDENTIFIED) ? "explicitly" : "implicitly");
proto_tree_add_text(tree, tvb, offset, 1,
"%s interface",
(octet & Q931_NOT_BASIC_CHANNEL) ? "Not basic" : "Basic");
proto_tree_add_text(tree, tvb, offset, 1,
"Indicated channel is %s",
(octet & 0x08) ? "required" : "preferred");
proto_tree_add_text(tree, tvb, offset, 1,
"Indicated channel is %sthe D-channel",
(octet & 0x04) ? "" : "not ");
if (octet & Q931_NOT_BASIC_CHANNEL) {
proto_tree_add_text(tree, tvb, offset, 1,
"Channel selection: %s",
val_to_str(octet & 0x03, q931_not_basic_channel_selection_vals,
"Unknown (0x%X)"));
} else {
proto_tree_add_text(tree, tvb, offset, 1,
"Channel selection: %s",
val_to_str(octet & 0x03, q931_basic_channel_selection_vals,
NULL));
}
offset += 1;
len -= 1;
if (octet & Q931_INTERFACE_IDENTIFIED) {
identifier_offset = offset;
identifier_len = 0;
do {
if (len == 0)
break;
octet = tvb_get_guint8(tvb, offset);
offset += 1;
len -= 1;
identifier_len++;
} while (!(octet & Q931_IE_VL_EXTENSION));
/*
* XXX - do we want to strip off the 8th bit on the
* last octet of the interface identifier?
*/
if (identifier_len != 0) {
proto_tree_add_text(tree, tvb, identifier_offset,
identifier_len, "Interface identifier: %s",
bytes_to_str(
tvb_get_ptr(tvb, identifier_offset, identifier_len),
identifier_len));
}
}
if (octet & Q931_NOT_BASIC_CHANNEL) {
if (len == 0)
return;
octet = tvb_get_guint8(tvb, offset);
coding_standard = octet & 0x60;
proto_tree_add_text(tree, tvb, offset, 1,
"Coding standard: %s",
val_to_str(coding_standard, q931_coding_standard_vals,
NULL));
if (coding_standard != Q931_ITU_STANDARDIZED_CODING) {
/*
* We don't know how the channel identifier is
* encoded, so just dump it as data and be done
* with it.
*/
proto_tree_add_text(tree, tvb, offset,
len, "Data: %s",
tvb_bytes_to_str(tvb, offset, len));
return;
}
proto_tree_add_text(tree, tvb, offset, 1,
"Channel is indicated by %s",
(octet & Q931_IS_SLOT_MAP) ? "slot map" : "number");
proto_tree_add_text(tree, tvb, offset, 1,
"%s type: %s",
(octet & Q931_IS_SLOT_MAP) ? "Map element" : "Channel",
val_to_str(octet & 0x0F, q931_element_type_vals,
"Unknown (0x%02X)"));
/*
* XXX - dump the channel number or slot map.
*/
}
}
/*
* Dissect a Progress indicator information element.
*/
static const value_string q931_progress_description_vals[] = {
{ 0x01, "Call is not end-to-end ISDN - progress information available in-band" },
{ 0x02, "Destination address is non-ISDN" },
{ 0x03, "Origination address is non-ISDN" },
{ 0x04, "Call has returned to the ISDN" },
{ 0x05, "Interworking has occurred and has resulted in a telecommunications service change" },
{ 0x08, "In-band information or an appropriate pattern is now available" },
{ 0, NULL }
};
void
dissect_q931_progress_indicator_ie(tvbuff_t *tvb, int offset, int len,
proto_tree *tree)
{
guint8 octet;
guint8 coding_standard;
if (len == 0)
return;
octet = tvb_get_guint8(tvb, offset);
coding_standard = octet & 0x60;
proto_tree_add_text(tree, tvb, offset, 1,
"Coding standard: %s",
val_to_str(coding_standard, q931_cause_coding_standard_vals, NULL));
if (coding_standard != Q931_ITU_STANDARDIZED_CODING) {
/*
* We don't know how the progress indicator is encoded,
* so just dump it as data and be done with it.
*/
proto_tree_add_text(tree, tvb, offset,
len, "Data: %s",
tvb_bytes_to_str(tvb, offset, len));
return;
}
proto_tree_add_text(tree, tvb, offset, 1,
"Location: %s",
val_to_str(octet & 0x0F, q931_cause_location_vals,
"Unknown (0x%X)"));
offset += 1;
len -= 1;
if (len == 0)
return;
octet = tvb_get_guint8(tvb, offset);
proto_tree_add_text(tree, tvb, offset, 1,
"Progress description: %s",
val_to_str(octet & 0x7F, q931_progress_description_vals,
"Unknown (0x%02X)"));
}
/*
* Dissect a Network-specific facilities or Transit network selection
* information element.
*/
static const value_string q931_netid_type_vals[] = {
{ 0x00, "User specified" },
{ 0x20, "National network identification" },
{ 0x30, "International network identification" },
{ 0, NULL }
};
static const value_string q931_netid_plan_vals[] = {
{ 0x00, "Unknown" },
{ 0x01, "Carrier Identification Code" },
{ 0x03, "X.121 data network identification code" },
{ 0, NULL }
};
static void
dissect_q931_ns_facilities_ie(tvbuff_t *tvb, int offset, int len,
proto_tree *tree)
{
guint8 octet;
int netid_len;
if (len == 0)
return;
octet = tvb_get_guint8(tvb, offset);
netid_len = octet & 0x7F;
proto_tree_add_text(tree, tvb, offset, 1,
"Network identification length: %u",
netid_len);
offset += 1;
len -= 1;
if (netid_len != 0) {
if (len == 0)
return;
octet = tvb_get_guint8(tvb, offset);
proto_tree_add_text(tree, tvb, offset, 1,
"Type of network identification: %s",
val_to_str(octet & 0x70, q931_netid_type_vals,
"Unknown (0x%02X)"));
proto_tree_add_text(tree, tvb, offset, 1,
"Network identification plan: %s",
val_to_str(octet & 0x0F, q931_netid_plan_vals,
"Unknown (0x%02X)"));
offset += 1;
len -= 1;
netid_len--;
if (len == 0)
return;
if (netid_len > len)
netid_len = len;
if (netid_len != 0) {
proto_tree_add_text(tree, tvb, offset, netid_len,
"Network identification: %s",
tvb_format_text(tvb, offset, netid_len));
offset += netid_len;
len -= netid_len;
}
}
/*
* Whatever is left is the network-specific facility
* specification.
*/
if (len == 0)
return;
proto_tree_add_text(tree, tvb, offset,
len, "Network-specific facility specification: %s",
tvb_bytes_to_str(tvb, offset, len));
}
/*
* Dissect a Notification indicator information element.
*/
static const value_string q931_notification_description_vals[] = {
{ 0x00, "User suspended" },
{ 0x01, "User resumed" },
{ 0x02, "Bearer service change" },
{ 0, NULL }
};
static void
dissect_q931_notification_indicator_ie(tvbuff_t *tvb, int offset, int len,
proto_tree *tree)
{
guint8 octet;
if (len == 0)
return;
octet = tvb_get_guint8(tvb, offset);
proto_tree_add_text(tree, tvb, offset, 1,
"Notification description: %s",
val_to_str(octet & 0x7F, q931_notification_description_vals,
"Unknown (0x%02X)"));
}
/*
* Dissect a Date/time information element.
*/
static void
dissect_q931_date_time_ie(tvbuff_t *tvb, int offset, int len,
proto_tree *tree)
{
if (len != 6) {
proto_tree_add_text(tree, tvb, offset, len,
"Date/time: length is %d, should be 6\n", len);
return;
}
/*
* XXX - what is "year" relative to? Is "month" 0-origin or
* 1-origin? Q.931 doesn't say....
*/
proto_tree_add_text(tree, tvb, offset, 6,
"Date/time: %02u-%02u-%02u %02u:%02u:%02u",
tvb_get_guint8(tvb, offset + 0), tvb_get_guint8(tvb, offset + 1), tvb_get_guint8(tvb, offset + 2),
tvb_get_guint8(tvb, offset + 3), tvb_get_guint8(tvb, offset + 4), tvb_get_guint8(tvb, offset + 5));
}
/*
* Dissect a Signal information element.
*/
static const value_string q931_signal_vals[] = {
{ 0x00, "Dial tone on" },
{ 0x01, "Ring tone on" },
{ 0x02, "Intercept tone on" },
{ 0x03, "Network congestion tone on" }, /* "fast busy" */
{ 0x04, "Busy tone on" },
{ 0x05, "Confirm tone on" },
{ 0x06, "Answer tone on" },
{ 0x07, "Call waiting tone on" },
{ 0x08, "Off-hook warning tone on" },
{ 0x09, "Preemption tone on" },
{ 0x3F, "Tones off" },
{ 0x40, "Alerting on - pattern 0" },
{ 0x41, "Alerting on - pattern 1" },
{ 0x42, "Alerting on - pattern 2" },
{ 0x43, "Alerting on - pattern 3" },
{ 0x44, "Alerting on - pattern 4" },
{ 0x45, "Alerting on - pattern 5" },
{ 0x46, "Alerting on - pattern 6" },
{ 0x47, "Alerting on - pattern 7" },
{ 0x4F, "Alerting off" },
{ 0, NULL }
};
static void
dissect_q931_signal_ie(tvbuff_t *tvb, int offset, int len,
proto_tree *tree)
{
if (len != 1) {
proto_tree_add_text(tree, tvb, offset, len,
"Signal: length is %d, should be 1\n", len);
return;
}
proto_tree_add_text(tree, tvb, offset, 1,
"Signal: %s",
val_to_str(tvb_get_guint8(tvb, offset), q931_signal_vals,
"Unknown (0x%02X)"));
}
/*
* Dissect an Information rate information element.
*/
static const value_string q931_throughput_class_vals[] = {
{ 0x03, "75 bit/s" },
{ 0x04, "150 bit/s" },
{ 0x05, "300 bit/s" },
{ 0x06, "600 bit/s" },
{ 0x07, "1200 bit/s" },
{ 0x08, "2400 bit/s" },
{ 0x09, "4800 bit/s" },
{ 0x0A, "9600 bit/s" },
{ 0x0B, "19200 bit/s" },
{ 0x0C, "48000 bit/s" },
{ 0x0D, "64000 bit/s" },
{ 0, NULL }
};
static void
dissect_q931_information_rate_ie(tvbuff_t *tvb, int offset, int len,
proto_tree *tree)
{
if (len != 4) {
proto_tree_add_text(tree, tvb, offset, len,
"Information rate: length is %d, should be 4\n", len);
return;
}
proto_tree_add_text(tree, tvb, offset + 0, 1,
"Incoming information rate: %s",
val_to_str(tvb_get_guint8(tvb, offset + 0) & 0x1F,
q931_throughput_class_vals, "Unknown (0x%02X)"));
proto_tree_add_text(tree, tvb, offset + 1, 1,
"Outgoing information rate: %s",
val_to_str(tvb_get_guint8(tvb, offset + 1) & 0x1F,
q931_throughput_class_vals, "Unknown (0x%02X)"));
proto_tree_add_text(tree, tvb, offset + 2, 1,
"Minimum incoming information rate: %s",
val_to_str(tvb_get_guint8(tvb, offset + 2) & 0x1F,
q931_throughput_class_vals, "Unknown (0x%02X)"));
proto_tree_add_text(tree, tvb, offset + 3, 1,
"Minimum outgoing information rate: %s",
val_to_str(tvb_get_guint8(tvb, offset + 3) & 0x1F,
q931_throughput_class_vals, "Unknown (0x%02X)"));
}
static int
dissect_q931_guint16_value(tvbuff_t *tvb, int offset, int len,
proto_tree *tree, char *label)
{
guint8 octet;
guint16 value;
int value_len;
value_len = 0;
octet = tvb_get_guint8(tvb, offset);
if (octet & Q931_IE_VL_EXTENSION) {
/*
* Only one octet long - error.
*/
goto bad_length;
}
value = (octet & 0x3) << 14;
offset += 1;
len -= 1;
value_len++;
if (len == 0) {
/*
* We've reached the end of the information element - error.
*/
goto past_end;
}
octet = tvb_get_guint8(tvb, offset);
if (octet & Q931_IE_VL_EXTENSION) {
/*
* Only two octets long - error.
*/
goto bad_length;
}
value |= (octet & 0x7F) << 7;
offset += 1;
len -= 1;
value_len++;
if (len == 0) {
/*
* We've reached the end of the information element - error.
*/
goto past_end;
}
octet = tvb_get_guint8(tvb, offset);
if (!(octet & Q931_IE_VL_EXTENSION)) {
/*
* More than three octets long - error.
*/
goto bad_length;
}
value |= (octet & 0x7F);
offset += 1;
len -= 1;
value_len++;
proto_tree_add_text(tree, tvb, offset, value_len, "%s: %u ms", label,
value);
return value_len;
past_end:
proto_tree_add_text(tree, tvb, offset, len,
"%s goes past end of information element", label);
return -1;
bad_length:
proto_tree_add_text(tree, tvb, offset, len, "%s isn't 3 octets long",
label);
return -1;
}
/*
* Dissect an End-to-end transit delay information element.
*/
static void
dissect_q931_e2e_transit_delay_ie(tvbuff_t *tvb, int offset, int len,
proto_tree *tree)
{
int value_len;
if (len == 0)
return;
value_len = dissect_q931_guint16_value(tvb, offset, len, tree,
"Cumulative transit delay");
if (value_len < 0)
return; /* error */
offset += value_len;
len -= value_len;
if (len == 0)
return;
value_len = dissect_q931_guint16_value(tvb, offset, len, tree,
"Requested end-to-end transit delay");
if (value_len < 0)
return; /* error */
offset += value_len;
len -= value_len;
if (len == 0)
return;
value_len = dissect_q931_guint16_value(tvb, offset, len, tree,
"Maximum end-to-end transit delay");
}
/*
* Dissect a Transit delay selection and indication information element.
*/
static void
dissect_q931_td_selection_and_int_ie(tvbuff_t *tvb, int offset, int len,
proto_tree *tree)
{
if (len == 0)
return;
dissect_q931_guint16_value(tvb, offset, len, tree,
"Transit delay");
}
/*
* Dissect a Packet layer binary parameters information element.
*/
static const value_string q931_fast_selected_vals[] = {
{ 0x00, "Fast select not requested" },
{ 0x08, "Fast select not requested" },
{ 0x10, "Fast select requested with no restriction of response" },
{ 0x18, "Fast select requested with restrictions of response" },
{ 0x00, NULL }
};
static void
dissect_q931_pl_binary_parameters_ie(tvbuff_t *tvb, int offset, int len,
proto_tree *tree)
{
guint8 octet;
if (len == 0)
return;
octet = tvb_get_guint8(tvb, offset);
proto_tree_add_text(tree, tvb, offset, 1,
"Fast select: %s",
val_to_str(octet & 0x18, q931_fast_selected_vals, NULL));
proto_tree_add_text(tree, tvb, offset, 1,
"%s",
(octet & 0x04) ? "No request/request denied" :
"Request indicated/request accepted");
proto_tree_add_text(tree, tvb, offset, 1,
"%s confirmation",
(octet & 0x02) ? "Link-by-link" : "End-to-end");
proto_tree_add_text(tree, tvb, offset, 1,
"Modulus %u sequencing",
(octet & 0x01) ? 8 : 128);
}
/*
* Dissect a Packet layer window size information element.
*/
static void
dissect_q931_pl_window_size_ie(tvbuff_t *tvb, int offset, int len,
proto_tree *tree)
{
if (len == 0)
return;
proto_tree_add_text(tree, tvb, offset, 1,
"Forward value: %u", tvb_get_guint8(tvb, offset) & 0x7F);
offset += 1;
len -= 1;
if (len == 0)
return;
proto_tree_add_text(tree, tvb, offset, 1,
"Backward value: %u", tvb_get_guint8(tvb, offset) & 0x7F);
}
/*
* Dissect a Packet size information element.
*/
static void
dissect_q931_packet_size_ie(tvbuff_t *tvb, int offset, int len,
proto_tree *tree)
{
if (len == 0)
return;
proto_tree_add_text(tree, tvb, offset, 1,
"Forward value: %u", tvb_get_guint8(tvb, offset) & 0x7F);
offset += 1;
len -= 1;
if (len == 0)
return;
proto_tree_add_text(tree, tvb, offset, 1,
"Backward value: %u", tvb_get_guint8(tvb, offset) & 0x7F);
}
/*
* Dissect a Closed user group information element.
*/
static const value_string q931_cug_indication_vals[] = {
{ 0x01, "Closed user group selection" },
{ 0x02, "Closed user group with outgoing access selection and indication" },
{ 0, NULL }
};
static void
dissect_q931_cug_ie(tvbuff_t *tvb, int offset, int len, proto_tree *tree)
{
if (len == 0)
return;
proto_tree_add_text(tree, tvb, offset, 1,
"CUG indication: %s",
val_to_str(tvb_get_guint8(tvb, offset) & 0x07,
q931_cug_indication_vals, "Unknown (0x%02X)"));
offset += 1;
len -= 1;
if (len == 0)
return;
proto_tree_add_text(tree, tvb, offset, len, "CUG index code: %s",
tvb_format_text(tvb, offset, len));
}
/*
* Dissect a Reverse charging indication information element.
*/
static const value_string q931_reverse_charging_indication_vals[] = {
{ 0x01, "Reverse charging requested" },
{ 0, NULL }
};
static void
dissect_q931_reverse_charge_ind_ie(tvbuff_t *tvb, int offset, int len,
proto_tree *tree)
{
if (len == 0)
return;
proto_tree_add_text(tree, tvb, offset, 1,
"Reverse charging indication: %s",
val_to_str(tvb_get_guint8(tvb, offset) & 0x07,
q931_reverse_charging_indication_vals, "Unknown (0x%02X)"));
}
/*
* Dissect a (phone) number information element.
*/
static const value_string q931_number_type_vals[] = {
{ 0x00, "Unknown" },
{ 0x10, "International number" },
{ 0x20, "National number" },
{ 0x30, "Network specific number" },
{ 0x40, "Subscriber number" },
{ 0x60, "Abbreviated number" },
{ 0, NULL }
};
static const value_string q931_numbering_plan_vals[] = {
{ 0x00, "Unknown" },
{ 0x01, "E.164 ISDN/telephony numbering" },
{ 0x03, "X.121 data numbering" },
{ 0x04, "F.69 Telex numbering" },
{ 0x08, "National standard numbering" },
{ 0x09, "Private numbering" },
{ 0, NULL }
};
static const value_string q931_presentation_indicator_vals[] = {
{ 0x00, "Presentation allowed" },
{ 0x20, "Presentation restricted" },
{ 0x40, "Number not available due to interworking" },
{ 0, NULL }
};
static const value_string q931_screening_indicator_vals[] = {
{ 0x00, "User-provided, not screened" },
{ 0x01, "User-provided, verified and passed" },
{ 0x02, "User-provided, verified and failed" },
{ 0x03, "Network-provided" },
{ 0, NULL }
};
static const value_string q931_redirection_reason_vals[] = {
{ 0x00, "Unknown" },
{ 0x01, "Call forwarding busy or called DTE busy" },
{ 0x02, "Call forwarding no reply" },
{ 0x04, "Call deflection" },
{ 0x09, "Called DTE out of order" },
{ 0x0A, "Call forwarding by the called DTE" },
{ 0x0F, "Call forwarding unconditional or systematic call redirection" },
{ 0, NULL }
};
static void
dissect_q931_number_ie(tvbuff_t *tvb, int offset, int len,
proto_tree *tree)
{
guint8 octet;
if (len == 0)
return;
octet = tvb_get_guint8(tvb, offset);
proto_tree_add_text(tree, tvb, offset, 1,
"Type of number: %s",
val_to_str(octet & 0x70, q931_number_type_vals,
"Unknown (0x%02X)"));
proto_tree_add_text(tree, tvb, offset, 1,
"Numbering plan: %s",
val_to_str(octet & 0x0F, q931_numbering_plan_vals,
"Unknown (0x%02X)"));
offset += 1;
len -= 1;
if (!(octet & Q931_IE_VL_EXTENSION)) {
if (len == 0)
return;
octet = tvb_get_guint8(tvb, offset);
proto_tree_add_text(tree, tvb, offset, 1,
"Presentation indicator: %s",
val_to_str(octet & 0x60, q931_presentation_indicator_vals,
"Unknown (0x%X)"));
proto_tree_add_text(tree, tvb, offset, 1,
"Screening indicator: %s",
val_to_str(octet & 0x03, q931_screening_indicator_vals,
"Unknown (0x%X)"));
offset += 1;
len -= 1;
}
/*
* XXX - only in a Redirecting number information element.
*/
if (!(octet & Q931_IE_VL_EXTENSION)) {
if (len == 0)
return;
octet = tvb_get_guint8(tvb, offset);
proto_tree_add_text(tree, tvb, offset, 1,
"Reason for redirection: %s",
val_to_str(octet & 0x0F, q931_redirection_reason_vals,
"Unknown (0x%X)"));
offset += 1;
len -= 1;
}
if (len == 0)
return;
proto_tree_add_text(tree, tvb, offset, len, "Number: %s",
tvb_format_text(tvb, offset, len));
}
/*
* Dissect a party subaddress information element.
*/
static const value_string q931_subaddress_type_vals[] = {
{ 0x00, "X.213/ISO 8348 Add.2 NSAP" },
{ 0x20, "User-specified" },
{ 0, NULL }
};
static const value_string q931_odd_even_indicator_vals[] = {
{ 0x00, "Even number of address signals" },
{ 0x10, "Odd number of address signals" },
{ 0, NULL }
};
static void
dissect_q931_party_subaddr_ie(tvbuff_t *tvb, int offset, int len,
proto_tree *tree)
{
guint8 octet;
if (len == 0)
return;
octet = tvb_get_guint8(tvb, offset);
proto_tree_add_text(tree, tvb, offset, 1,
"Type of subaddress: %s",
val_to_str(octet & 0x70, q931_subaddress_type_vals,
"Unknown (0x%02X)"));
proto_tree_add_text(tree, tvb, offset, 1,
"Odd/even indicator: %s",
val_to_str(octet & 0x10, q931_odd_even_indicator_vals,
NULL));
offset += 1;
len -= 1;
if (len == 0)
return;
proto_tree_add_text(tree, tvb, offset, len, "Subaddress: %s",
tvb_bytes_to_str(tvb, offset, len));
}
/*
* Dissect a Restart indicator information element.
*/
static const value_string q931_restart_indicator_class_vals[] = {
{ 0x00, "Indicated channels" },
{ 0x06, "Single interface" },
{ 0x07, "All interfaces" },
{ 0, NULL }
};
static void
dissect_q931_restart_indicator_ie(tvbuff_t *tvb, int offset, int len,
proto_tree *tree)
{
if (len != 1) {
proto_tree_add_text(tree, tvb, offset, len,
"Restart indicator: length is %d, should be 1\n", len);
return;
}
proto_tree_add_text(tree, tvb, offset, 1,
"Restart indicator: %s",
val_to_str(tvb_get_guint8(tvb, offset) & 0x07,
q931_restart_indicator_class_vals, "Unknown (0x%02X)"));
}
/*
* Dissect a High-layer compatibility information element.
*/
#define Q931_AUDIOVISUAL 0x60
static const value_string q931_high_layer_characteristics_vals[] = {
{ 0x01, "Telephony" },
{ 0x04, "F.182 Facsimile Group 2/3" },
{ 0x21, "F.184 Facsimile Group 4 Class I" },
{ 0x24, "F.230 Teletex, basic and mixed mode, and F.184 Facsimile Group 4, Classes II and III" },
{ 0x28, "F.220 Teletex, basic and processable mode" },
{ 0x31, "F.200 Teletex, basic mode" },
{ 0x32, "F.300 and T.102 syntax-based Videotex" },
{ 0x33, "F.300 and T.101 international Videotex interworking" },
{ 0x35, "F.60 Telex" },
{ 0x38, "X.400 Message Handling Systems" },
{ 0x41, "X.200 OSI application" },
{ 0x42, "FTAM application" },
{ 0x5E, "Reserved for maintenance" },
{ 0x5F, "Reserved for management" },
{ Q931_AUDIOVISUAL, "F.720/F.821 and F.731 Profile 1a videotelephony" },
{ 0x61, "F.702 and F.731 Profile 1b videoconferencing" },
{ 0x62, "F.702 and F.731 audiographic conferencing" },
{ 0, NULL }
};
static const value_string q931_audiovisual_characteristics_vals[] = {
{ 0x01, "Capability set of initial channel of H.221" },
{ 0x02, "Capability set of subsequent channel of H.221" },
{ 0x21, "Capability set of initial channel of an active 3.1kHz audio or speech call" },
{ 0x00, NULL }
};
void
dissect_q931_high_layer_compat_ie(tvbuff_t *tvb, int offset, int len,
proto_tree *tree)
{
guint8 octet;
guint8 coding_standard;
guint8 characteristics;
if (len == 0)
return;
octet = tvb_get_guint8(tvb, offset);
coding_standard = octet & 0x60;
proto_tree_add_text(tree, tvb, offset, 1,
"Coding standard: %s",
val_to_str(coding_standard, q931_coding_standard_vals, NULL));
if (coding_standard != Q931_ITU_STANDARDIZED_CODING) {
/*
* We don't know how the call state is encoded,
* so just dump it as data and be done with it.
*/
proto_tree_add_text(tree, tvb, offset,
len, "Data: %s",
tvb_bytes_to_str(tvb, offset, len));
return;
}
if (len == 0)
return;
octet = tvb_get_guint8(tvb, offset);
characteristics = octet & 0x7F;
proto_tree_add_text(tree, tvb, offset, 1,
"High layer characteristics identification: %s",
val_to_str(characteristics, q931_high_layer_characteristics_vals,
"Unknown (0x%02X)"));
offset += 1;
len -= 1;
if (!(octet & Q931_IE_VL_EXTENSION)) {
if (len == 0)
return;
octet = tvb_get_guint8(tvb, offset);
if (characteristics == Q931_AUDIOVISUAL) {
proto_tree_add_text(tree, tvb, offset, 1,
"Extended audiovisual characteristics identification: %s",
val_to_str(octet & 0x7F,
q931_audiovisual_characteristics_vals,
"Unknown (0x%02X)"));
} else {
proto_tree_add_text(tree, tvb, offset, 1,
"Extended high layer characteristics identification: %s",
val_to_str(octet & 0x7F,
q931_high_layer_characteristics_vals,
"Unknown (0x%02X)"));
}
}
}
/*
* Dissect a User-user information element.
*/
#define Q931_PROTOCOL_DISCRIMINATOR_IA5 0x04
static const value_string q931_protocol_discriminator_vals[] = {
{ 0x00, "User-specific protocol" },
{ 0x01, "OSI high layer protocols" },
{ 0x02, "X.244" },
{ Q931_PROTOCOL_DISCRIMINATOR_IA5, "IA5 characters" },
{ 0x05, "X.208 and X.209 coded user information" },
{ 0x07, "V.120 rate adaption" },
{ 0x08, "Q.931/I.451 user-network call control messages" },
{ 0, NULL }
};
static void
dissect_q931_user_user_ie(tvbuff_t *tvb, int offset, int len,
proto_tree *tree)
{
guint8 octet;
if (len == 0)
return;
octet = tvb_get_guint8(tvb, offset);
proto_tree_add_text(tree, tvb, offset, 1,
"Protocol discriminator: %s",
val_to_str(octet, q931_protocol_discriminator_vals,
"Unknown (0x%02x)"));
offset += 1;
len -= 1;
if (len == 0)
return;
switch (octet) {
case Q931_PROTOCOL_DISCRIMINATOR_IA5:
proto_tree_add_text(tree, tvb, offset, len, "User information: %s",
tvb_format_text(tvb, offset, len));
break;
default:
proto_tree_add_text(tree, tvb, offset, len, "User information: %s",
tvb_bytes_to_str(tvb, offset, len));
break;
}
}
/*
* Dissect information elements consisting of ASCII^H^H^H^H^HIA5 text.
*/
static void
dissect_q931_ia5_ie(tvbuff_t *tvb, int offset, int len, proto_tree *tree,
char *label)
{
if (len != 0) {
proto_tree_add_text(tree, tvb, offset, len, "%s: %s", label,
tvb_format_text(tvb, offset, len));
}
}
static const value_string q931_codeset_vals[] = {
{ 0x00, "Q.931 information elements" },
{ 0x04, "Information elements for ISO/IEC use" },
{ 0x05, "Information elements for national use" },
{ 0x06, "Information elements specific to the local network" },
{ 0x07, "User-specific information elements" },
{ 0x00, NULL },
};
static gboolean
q931_dissector(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree,
gboolean started_heuristic)
{
int offset = 0;
guint reported_length;
proto_tree *q931_tree = NULL;
proto_item *ti;
proto_tree *ie_tree;
guint8 call_ref_len;
guint8 call_ref[15];
guint8 message_type;
guint8 info_element;
guint16 info_element_len;
int codeset;
gboolean non_locking_shift;
guint8 protocol_discriminator;
int lv_tpkt_len;
#ifdef H323
tvbuff_t *h225_tvb;
gboolean is_h323_h225 = FALSE;
/*
* It is very much possible to find a TPKT header here
* TPKT is defined in RFC 1006 as a wrapper around ISO
* defined protocols. There could even be several TPKT
* wrapped messages in one TCP data field...
* XXXXXXXX THIS IS NOT IMPLEMENTED YET!!! XXXXXXXXXXX
*
* For Q.931 related messages this is easy. If a
* protocol discriminator is found with a value of 3
* and it's the first discriminator in the Q.931
* message one can safely assume it to be a TPKT
* header. See also Q.931 Table 4-1/Q.931
*/
#endif
protocol_discriminator = tvb_get_guint8( tvb, offset );
/* Keep the protocol discriminator for later use */
if ( started_heuristic ) {
/*
* The heuristic Q.931 message should conform to this
*/
if ( protocol_discriminator != NLPID_Q_931 )
return FALSE;
if ( ! is_tpkt( tvb, &offset ) )
return FALSE;
if ( tvb_length_remaining( tvb, offset ) <= 3 )
return FALSE;
}
/*
* The first byte should be < 8 (3 is TPKT, rest is Q.931)
*/
if ( protocol_discriminator < NLPID_Q_931 ) {
/*
* The minimum length of a Q.931 message is 3:
* 1 byte for the protocol discriminator,
* 1 for the call_reference length,
* and one for the message type.
*/
if ( tvb_length_remaining( tvb, offset ) <= 3 )
return FALSE;
/*
* OK, there are a couple of bytes available, but is there
* also a protocol discriminator?
*/
if ( tvb_length_remaining( tvb, offset ) > 4 ) {
/* Reread the protocol discriminator */
protocol_discriminator =
tvb_get_guint8( tvb, offset + 4);
} else {
/* No discriminator available */
protocol_discriminator = 0;
}
/*
* If it's not H.323 related Q.931 no heuristic action needed
* Dangerous, there might be other uses for this code.....
*/
if (started_heuristic && protocol_discriminator != NLPID_Q_931)
return FALSE;
/*
* Always check if it's a real TPKT message
*/
if ( ! is_tpkt( tvb, &offset ) )
return FALSE;
lv_tpkt_len = dissect_tpkt_header( tvb, &offset, pinfo, tree );
if (lv_tpkt_len == -1) {
/*
* TPKT isn't enabled.
*/
return FALSE;
}
/*
* Check if it's an empty TPKT message (the next one might be a
* real Q.931 message)
* Skip TPKT length!
*/
if ( tvb_length_remaining( tvb, offset ) < lv_tpkt_len - 4 ) {
return TRUE;
}
/*
* Reset the current_proto variable because dissect_tpkt
* messed with it
*/
if ( started_heuristic )
pinfo->current_proto = "Q.931 HEUR";
else
pinfo->current_proto = "Q.931";
}
/*
* The minimum length of a Q.931 message is
* 3, 1 byte for the protocol discr. 1 for the call_reference length,
* and one for the message type.
*/
if ( tvb_length_remaining( tvb, offset ) <= 3 ) {
return FALSE;
}
if (check_col(pinfo->fd, COL_PROTOCOL))
col_set_str(pinfo->fd, COL_PROTOCOL, "Q.931");
if (tree) {
ti = proto_tree_add_item(tree, proto_q931, tvb, offset,
tvb_length(tvb), FALSE);
q931_tree = proto_item_add_subtree(ti, ett_q931);
dissect_q931_protocol_discriminator(tvb, offset, q931_tree);
}
offset += 1;
call_ref_len = tvb_get_guint8(tvb, offset) & 0xF; /* XXX - do as a bit field? */
if (q931_tree != NULL)
proto_tree_add_uint(q931_tree, hf_q931_call_ref_len, tvb, offset, 1, call_ref_len);
offset += 1;
if (call_ref_len != 0) {
/* XXX - split this into flag and value */
tvb_memcpy(tvb, call_ref, offset, call_ref_len);
if (q931_tree != NULL)
proto_tree_add_bytes(q931_tree, hf_q931_call_ref, tvb, offset, call_ref_len, call_ref);
offset += call_ref_len;
}
message_type = tvb_get_guint8(tvb, offset);
if (check_col(pinfo->fd, COL_INFO)) {
col_add_str(pinfo->fd, COL_INFO,
val_to_str(message_type, q931_message_type_vals,
"Unknown message type (0x%02X)"));
}
if (q931_tree != NULL)
proto_tree_add_uint(q931_tree, hf_q931_message_type, tvb, offset, 1, message_type);
offset += 1;
/*
* And now for the information elements....
*/
codeset = 0; /* start out in codeset 0 */
non_locking_shift = TRUE;
reported_length = tvb_reported_length(tvb);
while (offset < reported_length) {
info_element = tvb_get_guint8(tvb, offset);
/*
* Check for the single-octet IEs.
*/
switch (info_element & Q931_IE_SO_IDENTIFIER_MASK) {
case Q931_IE_SHIFT:
non_locking_shift =
!(info_element & Q931_IE_SHIFT_LOCKING);
codeset = info_element & Q931_IE_SHIFT_CODESET;
if (q931_tree != NULL) {
proto_tree_add_text(q931_tree, tvb, offset, 1,
"%s shift to codeset %u: %s",
(non_locking_shift ? "Non-locking" : "Locking"),
codeset,
val_to_str(codeset, q931_codeset_vals,
"Unknown (0x%02X)"));
}
offset += 1;
continue;
case Q931_IE_MORE_DATA_OR_SEND_COMP:
switch (info_element) {
case Q931_IE_MORE_DATA:
if (q931_tree != NULL) {
proto_tree_add_text(q931_tree, tvb, offset, 1,
"More data");
}
break;
case Q931_IE_SENDING_COMPLETE:
if (q931_tree != NULL) {
proto_tree_add_text(q931_tree, tvb, offset, 1,
"Sending complete");
}
break;
default:
if (q931_tree != NULL) {
proto_tree_add_text(q931_tree, tvb, offset, 1,
"Unknown information element (0x%02X",
info_element);
}
break;
}
offset += 1;
if (non_locking_shift)
codeset = 0;
continue;
case Q931_IE_CONGESTION_LEVEL:
if (q931_tree != NULL) {
proto_tree_add_text(q931_tree, tvb, offset, 1,
"Congestion level: %s",
val_to_str(info_element & Q931_IE_SO_IE_MASK,
q931_congestion_level_vals,
"Unknown (0x%X)"));
}
offset += 1;
if (non_locking_shift)
codeset = 0;
continue;
case Q931_IE_REPEAT_INDICATOR:
if (q931_tree != NULL) {
proto_tree_add_text(q931_tree, tvb, offset, 1,
"Repeat indicator: %s",
val_to_str(info_element & Q931_IE_SO_IE_MASK,
q931_repeat_indication_vals,
"Unknown (0x%X)"));
}
offset += 1;
if (non_locking_shift)
codeset = 0;
continue;
default:
break;
}
/*
* Variable-length IE.
*/
#ifndef H323
info_element_len = tvb_get_guint8(tvb, offset + 1);
#else
/*
* According to page 18 from Recommendation H.225.0 :
* " Length of user-user contents contents
* - Shall be 2 octets instead of 1 (as in Figure 4-36/Q.931)"
*
* This will be true for all messages going to / from TCP port
* 1720 and with the first and fourth octet of the user-user
* IE having the values 0x7E and 0x05 resp.
* See http://www.mbuf.org/~moto/h323/h323decoder.html
*
*/
if ( ( tvb_get_guint8( tvb, offset ) == 0x7E ) &&
( tvb_get_guint8( tvb, offset + 3 ) == 0x05 ) &&
/* ( ( pinfo->srcport == 1720 ) || ( pinfo->destport == 1720 ) ) && */
( protocol_discriminator == NLPID_Q_931 ) ) {
info_element_len = tvb_get_ntohs( tvb, offset + 1 );
is_h323_h225 = TRUE;
if ( tree == NULL ) {
h225_tvb = tvb_new_subset( tvb, offset + 4, info_element_len - 1, info_element_len - 1 );
dissect_h225_cs( h225_tvb, pinfo, tree );
/*
* Skip the 4 bytes of the element header and then the element itself
*/
offset += 4;
offset += info_element_len - 1;
}
} else {
info_element_len = tvb_get_guint8( tvb, offset + 1 );
}
#endif
if (q931_tree != NULL) {
#ifdef H323
if (is_h323_h225) {
ti = proto_tree_add_text(q931_tree, tvb, offset,
1+1+1, "%s",
val_to_str(info_element,
q931_info_element_vals,
"Unknown information element (0x%02X)"));
ie_tree = proto_item_add_subtree(ti,
ett_q931_ie);
proto_tree_add_text(ie_tree, tvb, offset, 1,
"Information element: %s",
val_to_str(info_element,
q931_info_element_vals, "Unknown (0x%02X)"));
proto_tree_add_text(ie_tree, tvb, offset + 1,
2, "Length: %u", info_element_len);
} else {
#endif
ti = proto_tree_add_text(q931_tree, tvb, offset,
1+1+info_element_len, "%s",
val_to_str(info_element, q931_info_element_vals,
"Unknown information element (0x%02X)"));
ie_tree = proto_item_add_subtree(ti, ett_q931_ie);
proto_tree_add_text(ie_tree, tvb, offset, 1,
"Information element: %s",
val_to_str(info_element, q931_info_element_vals,
"Unknown (0x%02X)"));
proto_tree_add_text(ie_tree, tvb, offset + 1, 1,
"Length: %u", info_element_len);
#ifdef H323
}
#endif
switch (info_element) {
case Q931_IE_SEGMENTED_MESSAGE:
dissect_q931_segmented_message_ie(tvb,
offset + 2, info_element_len, ie_tree);
break;
case Q931_IE_BEARER_CAPABILITY:
case Q931_IE_LOW_LAYER_COMPAT:
dissect_q931_bearer_capability_ie(tvb,
offset + 2, info_element_len, ie_tree);
break;
case Q931_IE_CAUSE:
dissect_q931_cause_ie(tvb,
offset + 2, info_element_len, ie_tree);
break;
case Q931_IE_CALL_STATE:
dissect_q931_call_state_ie(tvb,
offset + 2, info_element_len, ie_tree);
break;
case Q931_IE_CHANNEL_IDENTIFICATION:
dissect_q931_channel_identification_ie(tvb,
offset + 2, info_element_len, ie_tree);
break;
case Q931_IE_PROGRESS_INDICATOR:
dissect_q931_progress_indicator_ie(tvb,
offset + 2, info_element_len, ie_tree);
break;
case Q931_IE_NETWORK_SPECIFIC_FACIL:
case Q931_IE_TRANSIT_NETWORK_SEL:
dissect_q931_ns_facilities_ie(tvb,
offset + 2, info_element_len, ie_tree);
break;
case Q931_IE_NOTIFICATION_INDICATOR:
dissect_q931_notification_indicator_ie(tvb,
offset + 2, info_element_len, ie_tree);
break;
case Q931_IE_DISPLAY:
dissect_q931_ia5_ie(tvb, offset + 2,
info_element_len, ie_tree,
"Display information");
break;
case Q931_IE_DATE_TIME:
dissect_q931_date_time_ie(tvb,
offset + 2, info_element_len, ie_tree);
break;
case Q931_IE_KEYPAD_FACILITY:
dissect_q931_ia5_ie(tvb, offset + 2,
info_element_len, ie_tree,
"Keypad facility");
break;
case Q931_IE_SIGNAL:
dissect_q931_signal_ie(tvb,
offset + 2, info_element_len, ie_tree);
break;
case Q931_IE_INFORMATION_RATE:
dissect_q931_information_rate_ie(tvb,
offset + 2, info_element_len, ie_tree);
break;
case Q931_IE_E2E_TRANSIT_DELAY:
dissect_q931_e2e_transit_delay_ie(tvb,
offset + 2, info_element_len, ie_tree);
break;
case Q931_IE_TD_SELECTION_AND_INT:
dissect_q931_td_selection_and_int_ie(tvb,
offset + 2, info_element_len, ie_tree);
break;
case Q931_IE_PL_BINARY_PARAMETERS:
dissect_q931_pl_binary_parameters_ie(tvb,
offset + 2, info_element_len, ie_tree);
break;
case Q931_IE_PL_WINDOW_SIZE:
dissect_q931_pl_window_size_ie(tvb,
offset + 2, info_element_len, ie_tree);
break;
case Q931_IE_PACKET_SIZE:
dissect_q931_packet_size_ie(tvb,
offset + 2, info_element_len, ie_tree);
break;
case Q931_IE_CUG:
dissect_q931_cug_ie(tvb,
offset + 2, info_element_len, ie_tree);
break;
case Q931_IE_REVERSE_CHARGE_IND:
dissect_q931_reverse_charge_ind_ie(tvb,
offset + 2, info_element_len, ie_tree);
break;
case Q931_IE_CALLING_PARTY_NUMBER:
case Q931_IE_CALLED_PARTY_NUMBER:
case Q931_IE_REDIRECTING_NUMBER:
dissect_q931_number_ie(tvb,
offset + 2, info_element_len, ie_tree);
break;
case Q931_IE_CALLING_PARTY_SUBADDR:
case Q931_IE_CALLED_PARTY_SUBADDR:
dissect_q931_party_subaddr_ie(tvb,
offset + 2, info_element_len, ie_tree);
break;
case Q931_IE_RESTART_INDICATOR:
dissect_q931_restart_indicator_ie(tvb,
offset + 2, info_element_len, ie_tree);
break;
case Q931_IE_HIGH_LAYER_COMPAT:
dissect_q931_high_layer_compat_ie(tvb,
offset + 2, info_element_len, ie_tree);
break;
case Q931_IE_USER_USER:
#ifdef H323
if (is_h323_h225) {
h225_tvb = tvb_new_subset(tvb,
offset + 4, info_element_len - 1,
info_element_len - 1);
dissect_h225_cs(h225_tvb, pinfo, tree);
offset += 3;
proto_tree_add_text(ie_tree, tvb,
offset, 1,
"Protocol discriminator: %s",
val_to_str(tvb_get_guint8(tvb, offset),
q931_protocol_discriminator_vals,
"Unknown (0x%02x)"));
offset += info_element_len;
} else {
#endif
dissect_q931_user_user_ie(tvb,
offset + 2, info_element_len,
ie_tree);
#ifdef H323
}
#endif
break;
default:
proto_tree_add_text(ie_tree, tvb, offset + 2,
info_element_len, "Data: %s",
bytes_to_str(
tvb_get_ptr(tvb, offset + 2, info_element_len),
info_element_len));
break;
}
}
offset += 1 + 1 + info_element_len;
if (non_locking_shift)
codeset = 0;
}
/*
* Heuristic should return TRUE if it get's here.
*/
return TRUE;
}
gboolean
dissect_q931_heur(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
{
/*
* XXX - should this be heuristic, or should we just make
* port 1720 do Q.931-inside-TPKT; that port appears to be
* intended for H.323 calls, according to
*
* http://www.isi.edu/in-notes/iana/assignments/port-numbers
*
* which says it's for "h323hostcall"?
*/
pinfo->current_proto = "Q.931 HEUR";
return q931_dissector(tvb, pinfo, tree, TRUE);
}
static void
dissect_q931(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
{
q931_dissector(tvb, pinfo, tree, FALSE);
}
void
proto_register_q931(void)
{
static hf_register_info hf[] = {
{ &hf_q931_discriminator,
{ "Protocol discriminator", "q931.disc", FT_UINT8, BASE_HEX, NULL, 0x0,
"", HFILL }},
{ &hf_q931_call_ref_len,
{ "Call reference value length", "q931.call_ref_len", FT_UINT8, BASE_DEC, NULL, 0x0,
"", HFILL }},
{ &hf_q931_call_ref,
{ "Call reference value", "q931.call_ref", FT_BYTES, BASE_HEX, NULL, 0x0,
"", HFILL }},
{ &hf_q931_message_type,
{ "Message type", "q931.message_type", FT_UINT8, BASE_HEX, VALS(q931_message_type_vals), 0x0,
"", HFILL }},
};
static gint *ett[] = {
&ett_q931,
&ett_q931_ie,
};
proto_q931 = proto_register_protocol("Q.931", "Q.931", "q931");
proto_register_field_array (proto_q931, hf, array_length(hf));
proto_register_subtree_array(ett, array_length(ett));
register_dissector("q931", dissect_q931, proto_q931);
}
void
proto_reg_handoff_q931(void)
{
heur_dissector_add("tcp", dissect_q931_heur, proto_q931);
}
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