wireshark/packet-sscop.c

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/* packet-sscop.c
* Routines for SSCOP (Q.2110, Q.SAAL) frame disassembly
* Guy Harris <guy@alum.mit.edu>
*
* $Id: packet-sscop.c,v 1.20 2002/08/28 21:00:35 jmayer Exp $
*
* 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
#include <stdio.h>
#include <glib.h>
#include <string.h>
#include <epan/packet.h>
static int proto_sscop = -1;
static gint ett_sscop = -1;
static dissector_handle_t q2931_handle;
static dissector_handle_t data_handle;
/*
* See
*
* http://www.protocols.com/pbook/atmsig.htm
*
* for some information on SSCOP, although, alas, not the actual PDU
* type values - those I got from the FreeBSD 3.2 ATM code.
*/
/*
* SSCOP PDU types.
*/
#define SSCOP_TYPE_MASK 0x0f
#define SSCOP_BGN 0x01 /* Begin */
#define SSCOP_BGAK 0x02 /* Begin Acknowledge */
#define SSCOP_BGREJ 0x07 /* Begin Reject */
#define SSCOP_END 0x03 /* End */
#define SSCOP_ENDAK 0x04 /* End Acknowledge */
#define SSCOP_RS 0x05 /* Resynchronization */
#define SSCOP_RSAK 0x06 /* Resynchronization Acknowledge */
#define SSCOP_SD 0x08 /* Sequenced Data */
#define SSCOP_SDP 0x09 /* Sequenced Data with Poll */
#define SSCOP_POLL 0x0a /* Status Request */
#define SSCOP_STAT 0x0b /* Solicited Status Response */
#define SSCOP_USTAT 0x0c /* Unsolicited Status Response */
#define SSCOP_UD 0x0d /* Unnumbered Data */
#define SSCOP_MD 0x0e /* Management Data */
#define SSCOP_ER 0x09 /* Error Recovery */
#define SSCOP_ERAK 0x0f /* Error Acknowledge */
#define SSCOP_S 0x10 /* Source bit in End PDU */
/*
* XXX - how to distinguish SDP from ER?
*/
static const value_string sscop_type_vals[] = {
{ SSCOP_BGN, "Begin" },
{ SSCOP_BGAK, "Begin Acknowledge" },
{ SSCOP_BGREJ, "Begin Reject" },
{ SSCOP_END, "End" },
{ SSCOP_ENDAK, "End Acknowledge" },
{ SSCOP_RS, "Resynchronization" },
{ SSCOP_RSAK, "Resynchronization Acknowledge" },
{ SSCOP_SD, "Sequenced Data" },
#if 0
{ SSCOP_SDP, "Sequenced Data with Poll" },
#endif
{ SSCOP_POLL, "Status Request" },
{ SSCOP_STAT, "Solicited Status Response" },
{ SSCOP_USTAT, "Unsolicited Status Response" },
{ SSCOP_UD, "Unnumbered Data" },
{ SSCOP_MD, "Management Data" },
{ SSCOP_ER, "Error Recovery" },
{ SSCOP_ERAK, "Error Acknowledge" },
{ 0, NULL }
};
/*
* The SSCOP "header" is a trailer, so the "offsets" are computed based
* on the length of the packet.
*/
/*
* PDU type.
*/
Add "tvb_reported_length()" to get the "reported length" of a tvbuff (i.e., the amount of data that was in the packet, even if not all of it was captured), for use when dissecting packets containing data that fills the packet (we want the dissector to try to dissect all of it; if it runs past the end of the captured data, we want it to throw an exception so that we'll put a "Short Frame" note in the protocol tree). This means we always want a tvbuff to have a real reported length value, so we make it an unsigned integer, and don't bother checking it for -1, as it should never be -1. If the reported length passed in to "tvb_set_subset()" is -1, set the reported length to the reported length of the tvbuff of which the new tvbuff will be a subset minus the offset in that tvbuff of the subset, so that "-1" means "what's left of the packet after we chop off the header". This is necessary in order to ensure that all tvbuffs have a real reported length value. Have "dissect_packet()" set the reported length of the top-level tvbuff to the reported length of the frame, so that we start out with a tvbuff with a real reported length value. Have "tvb_offset_exists()" return FALSE if the offset is past the end of the tvbuff. If the offset passed to it is postitive, have "compute_offset_length()" check for that it's not more than one byte past the end of the tvbuff - if it's just past the end, we don't want the check to fail, as we don't want attempts to create a subset tvbuff containing zero bytes to fail; that would be done if a captured packet was all header and no payload, and we'd want the dissector of the payload, not the dissector of the header, to throw an exception, as the problem isn't with the protocol for the header, it's with the protocol for the payload. Convert the ATM dissector, the SSCOP dissector, the Q.2931 dissector, and the Q.931 dissector to use tvbuffs. Make the LAPD dissector set up a tvbuff for the Q.931 dissector (it's not converted yet). svn path=/trunk/; revision=2023
2000-05-29 08:57:42 +00:00
#define SSCOP_PDU_TYPE (reported_length - 4) /* single byte */
/*
* Begin PDU, Begin Acknowledge PDU (no N(SQ) in it), Resynchronization
* PDU, Resynchronization Acknowledge PDU (no N(SQ) in it in Q.SAAL),
* Error Recovery PDU, Error Recovery Acknoledge PDU (no N(SQ) in it).
*/
Add "tvb_reported_length()" to get the "reported length" of a tvbuff (i.e., the amount of data that was in the packet, even if not all of it was captured), for use when dissecting packets containing data that fills the packet (we want the dissector to try to dissect all of it; if it runs past the end of the captured data, we want it to throw an exception so that we'll put a "Short Frame" note in the protocol tree). This means we always want a tvbuff to have a real reported length value, so we make it an unsigned integer, and don't bother checking it for -1, as it should never be -1. If the reported length passed in to "tvb_set_subset()" is -1, set the reported length to the reported length of the tvbuff of which the new tvbuff will be a subset minus the offset in that tvbuff of the subset, so that "-1" means "what's left of the packet after we chop off the header". This is necessary in order to ensure that all tvbuffs have a real reported length value. Have "dissect_packet()" set the reported length of the top-level tvbuff to the reported length of the frame, so that we start out with a tvbuff with a real reported length value. Have "tvb_offset_exists()" return FALSE if the offset is past the end of the tvbuff. If the offset passed to it is postitive, have "compute_offset_length()" check for that it's not more than one byte past the end of the tvbuff - if it's just past the end, we don't want the check to fail, as we don't want attempts to create a subset tvbuff containing zero bytes to fail; that would be done if a captured packet was all header and no payload, and we'd want the dissector of the payload, not the dissector of the header, to throw an exception, as the problem isn't with the protocol for the header, it's with the protocol for the payload. Convert the ATM dissector, the SSCOP dissector, the Q.2931 dissector, and the Q.931 dissector to use tvbuffs. Make the LAPD dissector set up a tvbuff for the Q.931 dissector (it's not converted yet). svn path=/trunk/; revision=2023
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#define SSCOP_N_SQ (reported_length - 5) /* One byte */
#define SSCOP_N_MR (reported_length - 4) /* lower 3 bytes thereof */
/*
* Sequenced Data PDU (no N(PS) in it), Sequenced Data with Poll PDU,
* Poll PDU.
*/
Add "tvb_reported_length()" to get the "reported length" of a tvbuff (i.e., the amount of data that was in the packet, even if not all of it was captured), for use when dissecting packets containing data that fills the packet (we want the dissector to try to dissect all of it; if it runs past the end of the captured data, we want it to throw an exception so that we'll put a "Short Frame" note in the protocol tree). This means we always want a tvbuff to have a real reported length value, so we make it an unsigned integer, and don't bother checking it for -1, as it should never be -1. If the reported length passed in to "tvb_set_subset()" is -1, set the reported length to the reported length of the tvbuff of which the new tvbuff will be a subset minus the offset in that tvbuff of the subset, so that "-1" means "what's left of the packet after we chop off the header". This is necessary in order to ensure that all tvbuffs have a real reported length value. Have "dissect_packet()" set the reported length of the top-level tvbuff to the reported length of the frame, so that we start out with a tvbuff with a real reported length value. Have "tvb_offset_exists()" return FALSE if the offset is past the end of the tvbuff. If the offset passed to it is postitive, have "compute_offset_length()" check for that it's not more than one byte past the end of the tvbuff - if it's just past the end, we don't want the check to fail, as we don't want attempts to create a subset tvbuff containing zero bytes to fail; that would be done if a captured packet was all header and no payload, and we'd want the dissector of the payload, not the dissector of the header, to throw an exception, as the problem isn't with the protocol for the header, it's with the protocol for the payload. Convert the ATM dissector, the SSCOP dissector, the Q.2931 dissector, and the Q.931 dissector to use tvbuffs. Make the LAPD dissector set up a tvbuff for the Q.931 dissector (it's not converted yet). svn path=/trunk/; revision=2023
2000-05-29 08:57:42 +00:00
#define SSCOP_N_PS (reported_length - 8) /* lower 3 bytes thereof */
#define SSCOP_N_S (reported_length - 4) /* lower 3 bytes thereof */
/*
* Solicited Status PDU, Unsolicited Status PDU (no N(PS) in it).
*/
Add "tvb_reported_length()" to get the "reported length" of a tvbuff (i.e., the amount of data that was in the packet, even if not all of it was captured), for use when dissecting packets containing data that fills the packet (we want the dissector to try to dissect all of it; if it runs past the end of the captured data, we want it to throw an exception so that we'll put a "Short Frame" note in the protocol tree). This means we always want a tvbuff to have a real reported length value, so we make it an unsigned integer, and don't bother checking it for -1, as it should never be -1. If the reported length passed in to "tvb_set_subset()" is -1, set the reported length to the reported length of the tvbuff of which the new tvbuff will be a subset minus the offset in that tvbuff of the subset, so that "-1" means "what's left of the packet after we chop off the header". This is necessary in order to ensure that all tvbuffs have a real reported length value. Have "dissect_packet()" set the reported length of the top-level tvbuff to the reported length of the frame, so that we start out with a tvbuff with a real reported length value. Have "tvb_offset_exists()" return FALSE if the offset is past the end of the tvbuff. If the offset passed to it is postitive, have "compute_offset_length()" check for that it's not more than one byte past the end of the tvbuff - if it's just past the end, we don't want the check to fail, as we don't want attempts to create a subset tvbuff containing zero bytes to fail; that would be done if a captured packet was all header and no payload, and we'd want the dissector of the payload, not the dissector of the header, to throw an exception, as the problem isn't with the protocol for the header, it's with the protocol for the payload. Convert the ATM dissector, the SSCOP dissector, the Q.2931 dissector, and the Q.931 dissector to use tvbuffs. Make the LAPD dissector set up a tvbuff for the Q.931 dissector (it's not converted yet). svn path=/trunk/; revision=2023
2000-05-29 08:57:42 +00:00
#define SSCOP_SS_N_PS (reported_length - 12) /* lower 3 bytes thereof */
#define SSCOP_SS_N_MR (reported_length - 8) /* lower 3 bytes thereof */
#define SSCOP_SS_N_R (reported_length - 4) /* lower 3 bytes thereof */
static void
Add "tvb_reported_length()" to get the "reported length" of a tvbuff (i.e., the amount of data that was in the packet, even if not all of it was captured), for use when dissecting packets containing data that fills the packet (we want the dissector to try to dissect all of it; if it runs past the end of the captured data, we want it to throw an exception so that we'll put a "Short Frame" note in the protocol tree). This means we always want a tvbuff to have a real reported length value, so we make it an unsigned integer, and don't bother checking it for -1, as it should never be -1. If the reported length passed in to "tvb_set_subset()" is -1, set the reported length to the reported length of the tvbuff of which the new tvbuff will be a subset minus the offset in that tvbuff of the subset, so that "-1" means "what's left of the packet after we chop off the header". This is necessary in order to ensure that all tvbuffs have a real reported length value. Have "dissect_packet()" set the reported length of the top-level tvbuff to the reported length of the frame, so that we start out with a tvbuff with a real reported length value. Have "tvb_offset_exists()" return FALSE if the offset is past the end of the tvbuff. If the offset passed to it is postitive, have "compute_offset_length()" check for that it's not more than one byte past the end of the tvbuff - if it's just past the end, we don't want the check to fail, as we don't want attempts to create a subset tvbuff containing zero bytes to fail; that would be done if a captured packet was all header and no payload, and we'd want the dissector of the payload, not the dissector of the header, to throw an exception, as the problem isn't with the protocol for the header, it's with the protocol for the payload. Convert the ATM dissector, the SSCOP dissector, the Q.2931 dissector, and the Q.931 dissector to use tvbuffs. Make the LAPD dissector set up a tvbuff for the Q.931 dissector (it's not converted yet). svn path=/trunk/; revision=2023
2000-05-29 08:57:42 +00:00
dissect_sscop(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
{
Add "tvb_reported_length()" to get the "reported length" of a tvbuff (i.e., the amount of data that was in the packet, even if not all of it was captured), for use when dissecting packets containing data that fills the packet (we want the dissector to try to dissect all of it; if it runs past the end of the captured data, we want it to throw an exception so that we'll put a "Short Frame" note in the protocol tree). This means we always want a tvbuff to have a real reported length value, so we make it an unsigned integer, and don't bother checking it for -1, as it should never be -1. If the reported length passed in to "tvb_set_subset()" is -1, set the reported length to the reported length of the tvbuff of which the new tvbuff will be a subset minus the offset in that tvbuff of the subset, so that "-1" means "what's left of the packet after we chop off the header". This is necessary in order to ensure that all tvbuffs have a real reported length value. Have "dissect_packet()" set the reported length of the top-level tvbuff to the reported length of the frame, so that we start out with a tvbuff with a real reported length value. Have "tvb_offset_exists()" return FALSE if the offset is past the end of the tvbuff. If the offset passed to it is postitive, have "compute_offset_length()" check for that it's not more than one byte past the end of the tvbuff - if it's just past the end, we don't want the check to fail, as we don't want attempts to create a subset tvbuff containing zero bytes to fail; that would be done if a captured packet was all header and no payload, and we'd want the dissector of the payload, not the dissector of the header, to throw an exception, as the problem isn't with the protocol for the header, it's with the protocol for the payload. Convert the ATM dissector, the SSCOP dissector, the Q.2931 dissector, and the Q.931 dissector to use tvbuffs. Make the LAPD dissector set up a tvbuff for the Q.931 dissector (it's not converted yet). svn path=/trunk/; revision=2023
2000-05-29 08:57:42 +00:00
guint reported_length;
proto_item *ti;
proto_tree *sscop_tree = NULL;
Add "tvb_reported_length()" to get the "reported length" of a tvbuff (i.e., the amount of data that was in the packet, even if not all of it was captured), for use when dissecting packets containing data that fills the packet (we want the dissector to try to dissect all of it; if it runs past the end of the captured data, we want it to throw an exception so that we'll put a "Short Frame" note in the protocol tree). This means we always want a tvbuff to have a real reported length value, so we make it an unsigned integer, and don't bother checking it for -1, as it should never be -1. If the reported length passed in to "tvb_set_subset()" is -1, set the reported length to the reported length of the tvbuff of which the new tvbuff will be a subset minus the offset in that tvbuff of the subset, so that "-1" means "what's left of the packet after we chop off the header". This is necessary in order to ensure that all tvbuffs have a real reported length value. Have "dissect_packet()" set the reported length of the top-level tvbuff to the reported length of the frame, so that we start out with a tvbuff with a real reported length value. Have "tvb_offset_exists()" return FALSE if the offset is past the end of the tvbuff. If the offset passed to it is postitive, have "compute_offset_length()" check for that it's not more than one byte past the end of the tvbuff - if it's just past the end, we don't want the check to fail, as we don't want attempts to create a subset tvbuff containing zero bytes to fail; that would be done if a captured packet was all header and no payload, and we'd want the dissector of the payload, not the dissector of the header, to throw an exception, as the problem isn't with the protocol for the header, it's with the protocol for the payload. Convert the ATM dissector, the SSCOP dissector, the Q.2931 dissector, and the Q.931 dissector to use tvbuffs. Make the LAPD dissector set up a tvbuff for the Q.931 dissector (it's not converted yet). svn path=/trunk/; revision=2023
2000-05-29 08:57:42 +00:00
guint8 sscop_pdu_type;
guint8 pdu_type;
int pdu_len;
int pad_len;
Add "tvb_reported_length()" to get the "reported length" of a tvbuff (i.e., the amount of data that was in the packet, even if not all of it was captured), for use when dissecting packets containing data that fills the packet (we want the dissector to try to dissect all of it; if it runs past the end of the captured data, we want it to throw an exception so that we'll put a "Short Frame" note in the protocol tree). This means we always want a tvbuff to have a real reported length value, so we make it an unsigned integer, and don't bother checking it for -1, as it should never be -1. If the reported length passed in to "tvb_set_subset()" is -1, set the reported length to the reported length of the tvbuff of which the new tvbuff will be a subset minus the offset in that tvbuff of the subset, so that "-1" means "what's left of the packet after we chop off the header". This is necessary in order to ensure that all tvbuffs have a real reported length value. Have "dissect_packet()" set the reported length of the top-level tvbuff to the reported length of the frame, so that we start out with a tvbuff with a real reported length value. Have "tvb_offset_exists()" return FALSE if the offset is past the end of the tvbuff. If the offset passed to it is postitive, have "compute_offset_length()" check for that it's not more than one byte past the end of the tvbuff - if it's just past the end, we don't want the check to fail, as we don't want attempts to create a subset tvbuff containing zero bytes to fail; that would be done if a captured packet was all header and no payload, and we'd want the dissector of the payload, not the dissector of the header, to throw an exception, as the problem isn't with the protocol for the header, it's with the protocol for the payload. Convert the ATM dissector, the SSCOP dissector, the Q.2931 dissector, and the Q.931 dissector to use tvbuffs. Make the LAPD dissector set up a tvbuff for the Q.931 dissector (it's not converted yet). svn path=/trunk/; revision=2023
2000-05-29 08:57:42 +00:00
tvbuff_t *next_tvb;
Add "tvb_reported_length()" to get the "reported length" of a tvbuff (i.e., the amount of data that was in the packet, even if not all of it was captured), for use when dissecting packets containing data that fills the packet (we want the dissector to try to dissect all of it; if it runs past the end of the captured data, we want it to throw an exception so that we'll put a "Short Frame" note in the protocol tree). This means we always want a tvbuff to have a real reported length value, so we make it an unsigned integer, and don't bother checking it for -1, as it should never be -1. If the reported length passed in to "tvb_set_subset()" is -1, set the reported length to the reported length of the tvbuff of which the new tvbuff will be a subset minus the offset in that tvbuff of the subset, so that "-1" means "what's left of the packet after we chop off the header". This is necessary in order to ensure that all tvbuffs have a real reported length value. Have "dissect_packet()" set the reported length of the top-level tvbuff to the reported length of the frame, so that we start out with a tvbuff with a real reported length value. Have "tvb_offset_exists()" return FALSE if the offset is past the end of the tvbuff. If the offset passed to it is postitive, have "compute_offset_length()" check for that it's not more than one byte past the end of the tvbuff - if it's just past the end, we don't want the check to fail, as we don't want attempts to create a subset tvbuff containing zero bytes to fail; that would be done if a captured packet was all header and no payload, and we'd want the dissector of the payload, not the dissector of the header, to throw an exception, as the problem isn't with the protocol for the header, it's with the protocol for the payload. Convert the ATM dissector, the SSCOP dissector, the Q.2931 dissector, and the Q.931 dissector to use tvbuffs. Make the LAPD dissector set up a tvbuff for the Q.931 dissector (it's not converted yet). svn path=/trunk/; revision=2023
2000-05-29 08:57:42 +00:00
reported_length = tvb_reported_length(tvb); /* frame length */
sscop_pdu_type = tvb_get_guint8(tvb, SSCOP_PDU_TYPE);
pdu_type = sscop_pdu_type & SSCOP_TYPE_MASK;
if (check_col(pinfo->cinfo, COL_PROTOCOL))
col_set_str(pinfo->cinfo, COL_PROTOCOL, "SSCOP");
if (check_col(pinfo->cinfo, COL_INFO))
col_add_str(pinfo->cinfo, COL_INFO, val_to_str(pdu_type, sscop_type_vals,
"Unknown PDU type (0x%02x)"));
/*
* Find the length of the PDU and, if there's any payload and
* padding, the length of the padding.
*/
switch (pdu_type) {
case SSCOP_SD:
Add "tvb_reported_length()" to get the "reported length" of a tvbuff (i.e., the amount of data that was in the packet, even if not all of it was captured), for use when dissecting packets containing data that fills the packet (we want the dissector to try to dissect all of it; if it runs past the end of the captured data, we want it to throw an exception so that we'll put a "Short Frame" note in the protocol tree). This means we always want a tvbuff to have a real reported length value, so we make it an unsigned integer, and don't bother checking it for -1, as it should never be -1. If the reported length passed in to "tvb_set_subset()" is -1, set the reported length to the reported length of the tvbuff of which the new tvbuff will be a subset minus the offset in that tvbuff of the subset, so that "-1" means "what's left of the packet after we chop off the header". This is necessary in order to ensure that all tvbuffs have a real reported length value. Have "dissect_packet()" set the reported length of the top-level tvbuff to the reported length of the frame, so that we start out with a tvbuff with a real reported length value. Have "tvb_offset_exists()" return FALSE if the offset is past the end of the tvbuff. If the offset passed to it is postitive, have "compute_offset_length()" check for that it's not more than one byte past the end of the tvbuff - if it's just past the end, we don't want the check to fail, as we don't want attempts to create a subset tvbuff containing zero bytes to fail; that would be done if a captured packet was all header and no payload, and we'd want the dissector of the payload, not the dissector of the header, to throw an exception, as the problem isn't with the protocol for the header, it's with the protocol for the payload. Convert the ATM dissector, the SSCOP dissector, the Q.2931 dissector, and the Q.931 dissector to use tvbuffs. Make the LAPD dissector set up a tvbuff for the Q.931 dissector (it's not converted yet). svn path=/trunk/; revision=2023
2000-05-29 08:57:42 +00:00
pad_len = (sscop_pdu_type >> 6) & 0x03;
pdu_len = 4;
break;
case SSCOP_BGN:
case SSCOP_BGAK:
case SSCOP_BGREJ:
case SSCOP_END:
case SSCOP_RS:
#if 0
case SSCOP_SDP:
#endif
Add "tvb_reported_length()" to get the "reported length" of a tvbuff (i.e., the amount of data that was in the packet, even if not all of it was captured), for use when dissecting packets containing data that fills the packet (we want the dissector to try to dissect all of it; if it runs past the end of the captured data, we want it to throw an exception so that we'll put a "Short Frame" note in the protocol tree). This means we always want a tvbuff to have a real reported length value, so we make it an unsigned integer, and don't bother checking it for -1, as it should never be -1. If the reported length passed in to "tvb_set_subset()" is -1, set the reported length to the reported length of the tvbuff of which the new tvbuff will be a subset minus the offset in that tvbuff of the subset, so that "-1" means "what's left of the packet after we chop off the header". This is necessary in order to ensure that all tvbuffs have a real reported length value. Have "dissect_packet()" set the reported length of the top-level tvbuff to the reported length of the frame, so that we start out with a tvbuff with a real reported length value. Have "tvb_offset_exists()" return FALSE if the offset is past the end of the tvbuff. If the offset passed to it is postitive, have "compute_offset_length()" check for that it's not more than one byte past the end of the tvbuff - if it's just past the end, we don't want the check to fail, as we don't want attempts to create a subset tvbuff containing zero bytes to fail; that would be done if a captured packet was all header and no payload, and we'd want the dissector of the payload, not the dissector of the header, to throw an exception, as the problem isn't with the protocol for the header, it's with the protocol for the payload. Convert the ATM dissector, the SSCOP dissector, the Q.2931 dissector, and the Q.931 dissector to use tvbuffs. Make the LAPD dissector set up a tvbuff for the Q.931 dissector (it's not converted yet). svn path=/trunk/; revision=2023
2000-05-29 08:57:42 +00:00
pad_len = (sscop_pdu_type >> 6) & 0x03;
pdu_len = 8;
break;
case SSCOP_UD:
Add "tvb_reported_length()" to get the "reported length" of a tvbuff (i.e., the amount of data that was in the packet, even if not all of it was captured), for use when dissecting packets containing data that fills the packet (we want the dissector to try to dissect all of it; if it runs past the end of the captured data, we want it to throw an exception so that we'll put a "Short Frame" note in the protocol tree). This means we always want a tvbuff to have a real reported length value, so we make it an unsigned integer, and don't bother checking it for -1, as it should never be -1. If the reported length passed in to "tvb_set_subset()" is -1, set the reported length to the reported length of the tvbuff of which the new tvbuff will be a subset minus the offset in that tvbuff of the subset, so that "-1" means "what's left of the packet after we chop off the header". This is necessary in order to ensure that all tvbuffs have a real reported length value. Have "dissect_packet()" set the reported length of the top-level tvbuff to the reported length of the frame, so that we start out with a tvbuff with a real reported length value. Have "tvb_offset_exists()" return FALSE if the offset is past the end of the tvbuff. If the offset passed to it is postitive, have "compute_offset_length()" check for that it's not more than one byte past the end of the tvbuff - if it's just past the end, we don't want the check to fail, as we don't want attempts to create a subset tvbuff containing zero bytes to fail; that would be done if a captured packet was all header and no payload, and we'd want the dissector of the payload, not the dissector of the header, to throw an exception, as the problem isn't with the protocol for the header, it's with the protocol for the payload. Convert the ATM dissector, the SSCOP dissector, the Q.2931 dissector, and the Q.931 dissector to use tvbuffs. Make the LAPD dissector set up a tvbuff for the Q.931 dissector (it's not converted yet). svn path=/trunk/; revision=2023
2000-05-29 08:57:42 +00:00
pad_len = (sscop_pdu_type >> 6) & 0x03;
pdu_len = 4;
break;
default:
pad_len = 0;
Add "tvb_reported_length()" to get the "reported length" of a tvbuff (i.e., the amount of data that was in the packet, even if not all of it was captured), for use when dissecting packets containing data that fills the packet (we want the dissector to try to dissect all of it; if it runs past the end of the captured data, we want it to throw an exception so that we'll put a "Short Frame" note in the protocol tree). This means we always want a tvbuff to have a real reported length value, so we make it an unsigned integer, and don't bother checking it for -1, as it should never be -1. If the reported length passed in to "tvb_set_subset()" is -1, set the reported length to the reported length of the tvbuff of which the new tvbuff will be a subset minus the offset in that tvbuff of the subset, so that "-1" means "what's left of the packet after we chop off the header". This is necessary in order to ensure that all tvbuffs have a real reported length value. Have "dissect_packet()" set the reported length of the top-level tvbuff to the reported length of the frame, so that we start out with a tvbuff with a real reported length value. Have "tvb_offset_exists()" return FALSE if the offset is past the end of the tvbuff. If the offset passed to it is postitive, have "compute_offset_length()" check for that it's not more than one byte past the end of the tvbuff - if it's just past the end, we don't want the check to fail, as we don't want attempts to create a subset tvbuff containing zero bytes to fail; that would be done if a captured packet was all header and no payload, and we'd want the dissector of the payload, not the dissector of the header, to throw an exception, as the problem isn't with the protocol for the header, it's with the protocol for the payload. Convert the ATM dissector, the SSCOP dissector, the Q.2931 dissector, and the Q.931 dissector to use tvbuffs. Make the LAPD dissector set up a tvbuff for the Q.931 dissector (it's not converted yet). svn path=/trunk/; revision=2023
2000-05-29 08:57:42 +00:00
pdu_len = reported_length; /* No payload, just SSCOP */
break;
}
if (tree) {
Add "tvb_reported_length()" to get the "reported length" of a tvbuff (i.e., the amount of data that was in the packet, even if not all of it was captured), for use when dissecting packets containing data that fills the packet (we want the dissector to try to dissect all of it; if it runs past the end of the captured data, we want it to throw an exception so that we'll put a "Short Frame" note in the protocol tree). This means we always want a tvbuff to have a real reported length value, so we make it an unsigned integer, and don't bother checking it for -1, as it should never be -1. If the reported length passed in to "tvb_set_subset()" is -1, set the reported length to the reported length of the tvbuff of which the new tvbuff will be a subset minus the offset in that tvbuff of the subset, so that "-1" means "what's left of the packet after we chop off the header". This is necessary in order to ensure that all tvbuffs have a real reported length value. Have "dissect_packet()" set the reported length of the top-level tvbuff to the reported length of the frame, so that we start out with a tvbuff with a real reported length value. Have "tvb_offset_exists()" return FALSE if the offset is past the end of the tvbuff. If the offset passed to it is postitive, have "compute_offset_length()" check for that it's not more than one byte past the end of the tvbuff - if it's just past the end, we don't want the check to fail, as we don't want attempts to create a subset tvbuff containing zero bytes to fail; that would be done if a captured packet was all header and no payload, and we'd want the dissector of the payload, not the dissector of the header, to throw an exception, as the problem isn't with the protocol for the header, it's with the protocol for the payload. Convert the ATM dissector, the SSCOP dissector, the Q.2931 dissector, and the Q.931 dissector to use tvbuffs. Make the LAPD dissector set up a tvbuff for the Q.931 dissector (it's not converted yet). svn path=/trunk/; revision=2023
2000-05-29 08:57:42 +00:00
ti = proto_tree_add_protocol_format(tree, proto_sscop, tvb,
reported_length - pdu_len,
pdu_len, "SSCOP");
sscop_tree = proto_item_add_subtree(ti, ett_sscop);
Add "tvb_reported_length()" to get the "reported length" of a tvbuff (i.e., the amount of data that was in the packet, even if not all of it was captured), for use when dissecting packets containing data that fills the packet (we want the dissector to try to dissect all of it; if it runs past the end of the captured data, we want it to throw an exception so that we'll put a "Short Frame" note in the protocol tree). This means we always want a tvbuff to have a real reported length value, so we make it an unsigned integer, and don't bother checking it for -1, as it should never be -1. If the reported length passed in to "tvb_set_subset()" is -1, set the reported length to the reported length of the tvbuff of which the new tvbuff will be a subset minus the offset in that tvbuff of the subset, so that "-1" means "what's left of the packet after we chop off the header". This is necessary in order to ensure that all tvbuffs have a real reported length value. Have "dissect_packet()" set the reported length of the top-level tvbuff to the reported length of the frame, so that we start out with a tvbuff with a real reported length value. Have "tvb_offset_exists()" return FALSE if the offset is past the end of the tvbuff. If the offset passed to it is postitive, have "compute_offset_length()" check for that it's not more than one byte past the end of the tvbuff - if it's just past the end, we don't want the check to fail, as we don't want attempts to create a subset tvbuff containing zero bytes to fail; that would be done if a captured packet was all header and no payload, and we'd want the dissector of the payload, not the dissector of the header, to throw an exception, as the problem isn't with the protocol for the header, it's with the protocol for the payload. Convert the ATM dissector, the SSCOP dissector, the Q.2931 dissector, and the Q.931 dissector to use tvbuffs. Make the LAPD dissector set up a tvbuff for the Q.931 dissector (it's not converted yet). svn path=/trunk/; revision=2023
2000-05-29 08:57:42 +00:00
proto_tree_add_text(sscop_tree, tvb, SSCOP_PDU_TYPE, 1,
"PDU Type: %s",
val_to_str(pdu_type, sscop_type_vals,
"Unknown (0x%02x)"));
switch (pdu_type) {
case SSCOP_BGN:
case SSCOP_RS:
case SSCOP_ER:
Add "tvb_reported_length()" to get the "reported length" of a tvbuff (i.e., the amount of data that was in the packet, even if not all of it was captured), for use when dissecting packets containing data that fills the packet (we want the dissector to try to dissect all of it; if it runs past the end of the captured data, we want it to throw an exception so that we'll put a "Short Frame" note in the protocol tree). This means we always want a tvbuff to have a real reported length value, so we make it an unsigned integer, and don't bother checking it for -1, as it should never be -1. If the reported length passed in to "tvb_set_subset()" is -1, set the reported length to the reported length of the tvbuff of which the new tvbuff will be a subset minus the offset in that tvbuff of the subset, so that "-1" means "what's left of the packet after we chop off the header". This is necessary in order to ensure that all tvbuffs have a real reported length value. Have "dissect_packet()" set the reported length of the top-level tvbuff to the reported length of the frame, so that we start out with a tvbuff with a real reported length value. Have "tvb_offset_exists()" return FALSE if the offset is past the end of the tvbuff. If the offset passed to it is postitive, have "compute_offset_length()" check for that it's not more than one byte past the end of the tvbuff - if it's just past the end, we don't want the check to fail, as we don't want attempts to create a subset tvbuff containing zero bytes to fail; that would be done if a captured packet was all header and no payload, and we'd want the dissector of the payload, not the dissector of the header, to throw an exception, as the problem isn't with the protocol for the header, it's with the protocol for the payload. Convert the ATM dissector, the SSCOP dissector, the Q.2931 dissector, and the Q.931 dissector to use tvbuffs. Make the LAPD dissector set up a tvbuff for the Q.931 dissector (it's not converted yet). svn path=/trunk/; revision=2023
2000-05-29 08:57:42 +00:00
proto_tree_add_text(sscop_tree, tvb, SSCOP_N_SQ, 1,
"N(SQ): %u", tvb_get_guint8(tvb, SSCOP_N_SQ));
proto_tree_add_text(sscop_tree, tvb, SSCOP_N_MR + 1, 3,
"N(MR): %u", tvb_get_ntohl(tvb, SSCOP_N_MR) & 0xFFFFFF);
break;
case SSCOP_END:
Add "tvb_reported_length()" to get the "reported length" of a tvbuff (i.e., the amount of data that was in the packet, even if not all of it was captured), for use when dissecting packets containing data that fills the packet (we want the dissector to try to dissect all of it; if it runs past the end of the captured data, we want it to throw an exception so that we'll put a "Short Frame" note in the protocol tree). This means we always want a tvbuff to have a real reported length value, so we make it an unsigned integer, and don't bother checking it for -1, as it should never be -1. If the reported length passed in to "tvb_set_subset()" is -1, set the reported length to the reported length of the tvbuff of which the new tvbuff will be a subset minus the offset in that tvbuff of the subset, so that "-1" means "what's left of the packet after we chop off the header". This is necessary in order to ensure that all tvbuffs have a real reported length value. Have "dissect_packet()" set the reported length of the top-level tvbuff to the reported length of the frame, so that we start out with a tvbuff with a real reported length value. Have "tvb_offset_exists()" return FALSE if the offset is past the end of the tvbuff. If the offset passed to it is postitive, have "compute_offset_length()" check for that it's not more than one byte past the end of the tvbuff - if it's just past the end, we don't want the check to fail, as we don't want attempts to create a subset tvbuff containing zero bytes to fail; that would be done if a captured packet was all header and no payload, and we'd want the dissector of the payload, not the dissector of the header, to throw an exception, as the problem isn't with the protocol for the header, it's with the protocol for the payload. Convert the ATM dissector, the SSCOP dissector, the Q.2931 dissector, and the Q.931 dissector to use tvbuffs. Make the LAPD dissector set up a tvbuff for the Q.931 dissector (it's not converted yet). svn path=/trunk/; revision=2023
2000-05-29 08:57:42 +00:00
proto_tree_add_text(sscop_tree, tvb, SSCOP_PDU_TYPE, 1,
"Source: %s", (sscop_pdu_type & SSCOP_S) ? "SSCOP" : "User");
break;
case SSCOP_BGAK:
case SSCOP_RSAK:
Add "tvb_reported_length()" to get the "reported length" of a tvbuff (i.e., the amount of data that was in the packet, even if not all of it was captured), for use when dissecting packets containing data that fills the packet (we want the dissector to try to dissect all of it; if it runs past the end of the captured data, we want it to throw an exception so that we'll put a "Short Frame" note in the protocol tree). This means we always want a tvbuff to have a real reported length value, so we make it an unsigned integer, and don't bother checking it for -1, as it should never be -1. If the reported length passed in to "tvb_set_subset()" is -1, set the reported length to the reported length of the tvbuff of which the new tvbuff will be a subset minus the offset in that tvbuff of the subset, so that "-1" means "what's left of the packet after we chop off the header". This is necessary in order to ensure that all tvbuffs have a real reported length value. Have "dissect_packet()" set the reported length of the top-level tvbuff to the reported length of the frame, so that we start out with a tvbuff with a real reported length value. Have "tvb_offset_exists()" return FALSE if the offset is past the end of the tvbuff. If the offset passed to it is postitive, have "compute_offset_length()" check for that it's not more than one byte past the end of the tvbuff - if it's just past the end, we don't want the check to fail, as we don't want attempts to create a subset tvbuff containing zero bytes to fail; that would be done if a captured packet was all header and no payload, and we'd want the dissector of the payload, not the dissector of the header, to throw an exception, as the problem isn't with the protocol for the header, it's with the protocol for the payload. Convert the ATM dissector, the SSCOP dissector, the Q.2931 dissector, and the Q.931 dissector to use tvbuffs. Make the LAPD dissector set up a tvbuff for the Q.931 dissector (it's not converted yet). svn path=/trunk/; revision=2023
2000-05-29 08:57:42 +00:00
proto_tree_add_text(sscop_tree, tvb, SSCOP_N_MR + 1, 3,
"N(MR): %u", tvb_get_ntohl(tvb, SSCOP_N_MR) & 0xFFFFFF);
break;
case SSCOP_ERAK:
Add "tvb_reported_length()" to get the "reported length" of a tvbuff (i.e., the amount of data that was in the packet, even if not all of it was captured), for use when dissecting packets containing data that fills the packet (we want the dissector to try to dissect all of it; if it runs past the end of the captured data, we want it to throw an exception so that we'll put a "Short Frame" note in the protocol tree). This means we always want a tvbuff to have a real reported length value, so we make it an unsigned integer, and don't bother checking it for -1, as it should never be -1. If the reported length passed in to "tvb_set_subset()" is -1, set the reported length to the reported length of the tvbuff of which the new tvbuff will be a subset minus the offset in that tvbuff of the subset, so that "-1" means "what's left of the packet after we chop off the header". This is necessary in order to ensure that all tvbuffs have a real reported length value. Have "dissect_packet()" set the reported length of the top-level tvbuff to the reported length of the frame, so that we start out with a tvbuff with a real reported length value. Have "tvb_offset_exists()" return FALSE if the offset is past the end of the tvbuff. If the offset passed to it is postitive, have "compute_offset_length()" check for that it's not more than one byte past the end of the tvbuff - if it's just past the end, we don't want the check to fail, as we don't want attempts to create a subset tvbuff containing zero bytes to fail; that would be done if a captured packet was all header and no payload, and we'd want the dissector of the payload, not the dissector of the header, to throw an exception, as the problem isn't with the protocol for the header, it's with the protocol for the payload. Convert the ATM dissector, the SSCOP dissector, the Q.2931 dissector, and the Q.931 dissector to use tvbuffs. Make the LAPD dissector set up a tvbuff for the Q.931 dissector (it's not converted yet). svn path=/trunk/; revision=2023
2000-05-29 08:57:42 +00:00
proto_tree_add_text(sscop_tree, tvb, SSCOP_N_MR + 3, 3,
"N(MR): %u", tvb_get_ntohl(tvb, SSCOP_N_MR) & 0xFFFFFF);
break;
case SSCOP_SD:
Add "tvb_reported_length()" to get the "reported length" of a tvbuff (i.e., the amount of data that was in the packet, even if not all of it was captured), for use when dissecting packets containing data that fills the packet (we want the dissector to try to dissect all of it; if it runs past the end of the captured data, we want it to throw an exception so that we'll put a "Short Frame" note in the protocol tree). This means we always want a tvbuff to have a real reported length value, so we make it an unsigned integer, and don't bother checking it for -1, as it should never be -1. If the reported length passed in to "tvb_set_subset()" is -1, set the reported length to the reported length of the tvbuff of which the new tvbuff will be a subset minus the offset in that tvbuff of the subset, so that "-1" means "what's left of the packet after we chop off the header". This is necessary in order to ensure that all tvbuffs have a real reported length value. Have "dissect_packet()" set the reported length of the top-level tvbuff to the reported length of the frame, so that we start out with a tvbuff with a real reported length value. Have "tvb_offset_exists()" return FALSE if the offset is past the end of the tvbuff. If the offset passed to it is postitive, have "compute_offset_length()" check for that it's not more than one byte past the end of the tvbuff - if it's just past the end, we don't want the check to fail, as we don't want attempts to create a subset tvbuff containing zero bytes to fail; that would be done if a captured packet was all header and no payload, and we'd want the dissector of the payload, not the dissector of the header, to throw an exception, as the problem isn't with the protocol for the header, it's with the protocol for the payload. Convert the ATM dissector, the SSCOP dissector, the Q.2931 dissector, and the Q.931 dissector to use tvbuffs. Make the LAPD dissector set up a tvbuff for the Q.931 dissector (it's not converted yet). svn path=/trunk/; revision=2023
2000-05-29 08:57:42 +00:00
proto_tree_add_text(sscop_tree, tvb, SSCOP_N_S + 1, 3,
"N(S): %u", tvb_get_ntohl(tvb, SSCOP_N_S) & 0xFFFFFF);
break;
#if 0
case SSCOP_SDP:
#endif
case SSCOP_POLL:
Add "tvb_reported_length()" to get the "reported length" of a tvbuff (i.e., the amount of data that was in the packet, even if not all of it was captured), for use when dissecting packets containing data that fills the packet (we want the dissector to try to dissect all of it; if it runs past the end of the captured data, we want it to throw an exception so that we'll put a "Short Frame" note in the protocol tree). This means we always want a tvbuff to have a real reported length value, so we make it an unsigned integer, and don't bother checking it for -1, as it should never be -1. If the reported length passed in to "tvb_set_subset()" is -1, set the reported length to the reported length of the tvbuff of which the new tvbuff will be a subset minus the offset in that tvbuff of the subset, so that "-1" means "what's left of the packet after we chop off the header". This is necessary in order to ensure that all tvbuffs have a real reported length value. Have "dissect_packet()" set the reported length of the top-level tvbuff to the reported length of the frame, so that we start out with a tvbuff with a real reported length value. Have "tvb_offset_exists()" return FALSE if the offset is past the end of the tvbuff. If the offset passed to it is postitive, have "compute_offset_length()" check for that it's not more than one byte past the end of the tvbuff - if it's just past the end, we don't want the check to fail, as we don't want attempts to create a subset tvbuff containing zero bytes to fail; that would be done if a captured packet was all header and no payload, and we'd want the dissector of the payload, not the dissector of the header, to throw an exception, as the problem isn't with the protocol for the header, it's with the protocol for the payload. Convert the ATM dissector, the SSCOP dissector, the Q.2931 dissector, and the Q.931 dissector to use tvbuffs. Make the LAPD dissector set up a tvbuff for the Q.931 dissector (it's not converted yet). svn path=/trunk/; revision=2023
2000-05-29 08:57:42 +00:00
proto_tree_add_text(sscop_tree, tvb, SSCOP_N_PS + 1, 3,
"N(PS): %u", tvb_get_ntohl(tvb, SSCOP_N_PS) & 0xFFFFFF);
proto_tree_add_text(sscop_tree, tvb, SSCOP_N_S + 1, 3,
"N(S): %u", tvb_get_ntohl(tvb, SSCOP_N_S) & 0xFFFFFF);
break;
case SSCOP_STAT:
/*
* XXX - dissect the list elements....
*/
Add "tvb_reported_length()" to get the "reported length" of a tvbuff (i.e., the amount of data that was in the packet, even if not all of it was captured), for use when dissecting packets containing data that fills the packet (we want the dissector to try to dissect all of it; if it runs past the end of the captured data, we want it to throw an exception so that we'll put a "Short Frame" note in the protocol tree). This means we always want a tvbuff to have a real reported length value, so we make it an unsigned integer, and don't bother checking it for -1, as it should never be -1. If the reported length passed in to "tvb_set_subset()" is -1, set the reported length to the reported length of the tvbuff of which the new tvbuff will be a subset minus the offset in that tvbuff of the subset, so that "-1" means "what's left of the packet after we chop off the header". This is necessary in order to ensure that all tvbuffs have a real reported length value. Have "dissect_packet()" set the reported length of the top-level tvbuff to the reported length of the frame, so that we start out with a tvbuff with a real reported length value. Have "tvb_offset_exists()" return FALSE if the offset is past the end of the tvbuff. If the offset passed to it is postitive, have "compute_offset_length()" check for that it's not more than one byte past the end of the tvbuff - if it's just past the end, we don't want the check to fail, as we don't want attempts to create a subset tvbuff containing zero bytes to fail; that would be done if a captured packet was all header and no payload, and we'd want the dissector of the payload, not the dissector of the header, to throw an exception, as the problem isn't with the protocol for the header, it's with the protocol for the payload. Convert the ATM dissector, the SSCOP dissector, the Q.2931 dissector, and the Q.931 dissector to use tvbuffs. Make the LAPD dissector set up a tvbuff for the Q.931 dissector (it's not converted yet). svn path=/trunk/; revision=2023
2000-05-29 08:57:42 +00:00
proto_tree_add_text(sscop_tree, tvb, SSCOP_SS_N_PS + 1, 3,
"N(PS): %u", tvb_get_ntohl(tvb, SSCOP_SS_N_PS) & 0xFFFFFF);
proto_tree_add_text(sscop_tree, tvb, SSCOP_SS_N_MR + 1, 3,
"N(MR): %u", tvb_get_ntohl(tvb, SSCOP_SS_N_MR) & 0xFFFFFF);
proto_tree_add_text(sscop_tree, tvb, SSCOP_SS_N_R + 1, 3,
"N(R): %u", tvb_get_ntohl(tvb, SSCOP_SS_N_R) & 0xFFFFFF);
break;
case SSCOP_USTAT:
/*
* XXX - dissect the list elements....
*/
Add "tvb_reported_length()" to get the "reported length" of a tvbuff (i.e., the amount of data that was in the packet, even if not all of it was captured), for use when dissecting packets containing data that fills the packet (we want the dissector to try to dissect all of it; if it runs past the end of the captured data, we want it to throw an exception so that we'll put a "Short Frame" note in the protocol tree). This means we always want a tvbuff to have a real reported length value, so we make it an unsigned integer, and don't bother checking it for -1, as it should never be -1. If the reported length passed in to "tvb_set_subset()" is -1, set the reported length to the reported length of the tvbuff of which the new tvbuff will be a subset minus the offset in that tvbuff of the subset, so that "-1" means "what's left of the packet after we chop off the header". This is necessary in order to ensure that all tvbuffs have a real reported length value. Have "dissect_packet()" set the reported length of the top-level tvbuff to the reported length of the frame, so that we start out with a tvbuff with a real reported length value. Have "tvb_offset_exists()" return FALSE if the offset is past the end of the tvbuff. If the offset passed to it is postitive, have "compute_offset_length()" check for that it's not more than one byte past the end of the tvbuff - if it's just past the end, we don't want the check to fail, as we don't want attempts to create a subset tvbuff containing zero bytes to fail; that would be done if a captured packet was all header and no payload, and we'd want the dissector of the payload, not the dissector of the header, to throw an exception, as the problem isn't with the protocol for the header, it's with the protocol for the payload. Convert the ATM dissector, the SSCOP dissector, the Q.2931 dissector, and the Q.931 dissector to use tvbuffs. Make the LAPD dissector set up a tvbuff for the Q.931 dissector (it's not converted yet). svn path=/trunk/; revision=2023
2000-05-29 08:57:42 +00:00
proto_tree_add_text(sscop_tree, tvb, SSCOP_SS_N_MR + 1, 3,
"N(MR): %u", tvb_get_ntohl(tvb, SSCOP_SS_N_MR) & 0xFFFFFF);
proto_tree_add_text(sscop_tree, tvb, SSCOP_SS_N_R + 1, 3,
"N(R): %u", tvb_get_ntohl(tvb, SSCOP_SS_N_R) & 0xFFFFFF);
break;
}
}
/*
* Dissect the payload, if any.
*
* XXX - what about a Management Data PDU?
*/
switch (pdu_type) {
case SSCOP_SD:
case SSCOP_UD:
case SSCOP_BGN:
case SSCOP_BGAK:
case SSCOP_BGREJ:
case SSCOP_END:
case SSCOP_RS:
#if 0
case SSCOP_SDP:
#endif
if (tree) {
Add "tvb_reported_length()" to get the "reported length" of a tvbuff (i.e., the amount of data that was in the packet, even if not all of it was captured), for use when dissecting packets containing data that fills the packet (we want the dissector to try to dissect all of it; if it runs past the end of the captured data, we want it to throw an exception so that we'll put a "Short Frame" note in the protocol tree). This means we always want a tvbuff to have a real reported length value, so we make it an unsigned integer, and don't bother checking it for -1, as it should never be -1. If the reported length passed in to "tvb_set_subset()" is -1, set the reported length to the reported length of the tvbuff of which the new tvbuff will be a subset minus the offset in that tvbuff of the subset, so that "-1" means "what's left of the packet after we chop off the header". This is necessary in order to ensure that all tvbuffs have a real reported length value. Have "dissect_packet()" set the reported length of the top-level tvbuff to the reported length of the frame, so that we start out with a tvbuff with a real reported length value. Have "tvb_offset_exists()" return FALSE if the offset is past the end of the tvbuff. If the offset passed to it is postitive, have "compute_offset_length()" check for that it's not more than one byte past the end of the tvbuff - if it's just past the end, we don't want the check to fail, as we don't want attempts to create a subset tvbuff containing zero bytes to fail; that would be done if a captured packet was all header and no payload, and we'd want the dissector of the payload, not the dissector of the header, to throw an exception, as the problem isn't with the protocol for the header, it's with the protocol for the payload. Convert the ATM dissector, the SSCOP dissector, the Q.2931 dissector, and the Q.931 dissector to use tvbuffs. Make the LAPD dissector set up a tvbuff for the Q.931 dissector (it's not converted yet). svn path=/trunk/; revision=2023
2000-05-29 08:57:42 +00:00
proto_tree_add_text(sscop_tree, tvb, SSCOP_PDU_TYPE, 1,
"Pad length: %u", pad_len);
}
/*
* Compute length of data in PDU - subtract the trailer length
Add "tvb_reported_length()" to get the "reported length" of a tvbuff (i.e., the amount of data that was in the packet, even if not all of it was captured), for use when dissecting packets containing data that fills the packet (we want the dissector to try to dissect all of it; if it runs past the end of the captured data, we want it to throw an exception so that we'll put a "Short Frame" note in the protocol tree). This means we always want a tvbuff to have a real reported length value, so we make it an unsigned integer, and don't bother checking it for -1, as it should never be -1. If the reported length passed in to "tvb_set_subset()" is -1, set the reported length to the reported length of the tvbuff of which the new tvbuff will be a subset minus the offset in that tvbuff of the subset, so that "-1" means "what's left of the packet after we chop off the header". This is necessary in order to ensure that all tvbuffs have a real reported length value. Have "dissect_packet()" set the reported length of the top-level tvbuff to the reported length of the frame, so that we start out with a tvbuff with a real reported length value. Have "tvb_offset_exists()" return FALSE if the offset is past the end of the tvbuff. If the offset passed to it is postitive, have "compute_offset_length()" check for that it's not more than one byte past the end of the tvbuff - if it's just past the end, we don't want the check to fail, as we don't want attempts to create a subset tvbuff containing zero bytes to fail; that would be done if a captured packet was all header and no payload, and we'd want the dissector of the payload, not the dissector of the header, to throw an exception, as the problem isn't with the protocol for the header, it's with the protocol for the payload. Convert the ATM dissector, the SSCOP dissector, the Q.2931 dissector, and the Q.931 dissector to use tvbuffs. Make the LAPD dissector set up a tvbuff for the Q.931 dissector (it's not converted yet). svn path=/trunk/; revision=2023
2000-05-29 08:57:42 +00:00
* and the pad length from the reported length.
*/
Add "tvb_reported_length()" to get the "reported length" of a tvbuff (i.e., the amount of data that was in the packet, even if not all of it was captured), for use when dissecting packets containing data that fills the packet (we want the dissector to try to dissect all of it; if it runs past the end of the captured data, we want it to throw an exception so that we'll put a "Short Frame" note in the protocol tree). This means we always want a tvbuff to have a real reported length value, so we make it an unsigned integer, and don't bother checking it for -1, as it should never be -1. If the reported length passed in to "tvb_set_subset()" is -1, set the reported length to the reported length of the tvbuff of which the new tvbuff will be a subset minus the offset in that tvbuff of the subset, so that "-1" means "what's left of the packet after we chop off the header". This is necessary in order to ensure that all tvbuffs have a real reported length value. Have "dissect_packet()" set the reported length of the top-level tvbuff to the reported length of the frame, so that we start out with a tvbuff with a real reported length value. Have "tvb_offset_exists()" return FALSE if the offset is past the end of the tvbuff. If the offset passed to it is postitive, have "compute_offset_length()" check for that it's not more than one byte past the end of the tvbuff - if it's just past the end, we don't want the check to fail, as we don't want attempts to create a subset tvbuff containing zero bytes to fail; that would be done if a captured packet was all header and no payload, and we'd want the dissector of the payload, not the dissector of the header, to throw an exception, as the problem isn't with the protocol for the header, it's with the protocol for the payload. Convert the ATM dissector, the SSCOP dissector, the Q.2931 dissector, and the Q.931 dissector to use tvbuffs. Make the LAPD dissector set up a tvbuff for the Q.931 dissector (it's not converted yet). svn path=/trunk/; revision=2023
2000-05-29 08:57:42 +00:00
reported_length -= (pdu_len + pad_len);
/*
* XXX - if more than just Q.2931 uses SSCOP, we need to tell
* SSCOP what dissector to use here.
*/
Add "tvb_reported_length()" to get the "reported length" of a tvbuff (i.e., the amount of data that was in the packet, even if not all of it was captured), for use when dissecting packets containing data that fills the packet (we want the dissector to try to dissect all of it; if it runs past the end of the captured data, we want it to throw an exception so that we'll put a "Short Frame" note in the protocol tree). This means we always want a tvbuff to have a real reported length value, so we make it an unsigned integer, and don't bother checking it for -1, as it should never be -1. If the reported length passed in to "tvb_set_subset()" is -1, set the reported length to the reported length of the tvbuff of which the new tvbuff will be a subset minus the offset in that tvbuff of the subset, so that "-1" means "what's left of the packet after we chop off the header". This is necessary in order to ensure that all tvbuffs have a real reported length value. Have "dissect_packet()" set the reported length of the top-level tvbuff to the reported length of the frame, so that we start out with a tvbuff with a real reported length value. Have "tvb_offset_exists()" return FALSE if the offset is past the end of the tvbuff. If the offset passed to it is postitive, have "compute_offset_length()" check for that it's not more than one byte past the end of the tvbuff - if it's just past the end, we don't want the check to fail, as we don't want attempts to create a subset tvbuff containing zero bytes to fail; that would be done if a captured packet was all header and no payload, and we'd want the dissector of the payload, not the dissector of the header, to throw an exception, as the problem isn't with the protocol for the header, it's with the protocol for the payload. Convert the ATM dissector, the SSCOP dissector, the Q.2931 dissector, and the Q.931 dissector to use tvbuffs. Make the LAPD dissector set up a tvbuff for the Q.931 dissector (it's not converted yet). svn path=/trunk/; revision=2023
2000-05-29 08:57:42 +00:00
if (reported_length != 0) {
/*
* We know that we have all of the payload, because we know we have
* at least 4 bytes of data after the payload, i.e. the SSCOP trailer.
* Therefore, we know that the captured length of the payload is
* equal to the length of the payload.
*/
next_tvb = tvb_new_subset(tvb, 0, reported_length, reported_length);
if (pdu_type == SSCOP_SD)
call_dissector(q2931_handle, next_tvb, pinfo, tree);
else
call_dissector(data_handle,next_tvb, pinfo, tree);
}
break;
}
}
void
proto_register_sscop(void)
{
static gint *ett[] = {
&ett_sscop,
};
proto_sscop = proto_register_protocol("SSCOP", "SSCOP", "sscop");
proto_register_subtree_array(ett, array_length(ett));
register_dissector("sscop", dissect_sscop, proto_sscop);
}
void
proto_reg_handoff_sscop(void)
{
/*
* Get handle for the Q.2931 dissector.
*/
q2931_handle = find_dissector("q2931");
data_handle = find_dissector("data");
}