osmocom/wireshark
14
0
Fork 1
Code Issues Pull requests Projects Releases Wiki Activity
wireshark/epan/dissectors/packet-ascend.c
Guy Harris 75c739e4b7 ISDN, LAPD: clean up the way they connect to other dissectors. 
Have the ISDN dissector take the ISDN pseudo-header through its data
argument, rather than assuming it's in pinfo->pseudo_header, so it can
be used if the link-layer type of the capture isn't ISDN.

Have it add the direction to its protocol tree, so it's there for all
ISDN packets.

Have more versions of the LAPD dissector:

	one where the ISDN direction information is available through
	an ISDN pseudo-header passed as its data argument;

	one for use when the link-layer type *is* LAPD, where the ISDN
	direction information may be available through the direction
	part of the packet flags.

Pass more flags to the routine that does LAPD dissection to indicate the
direction (user->network or network->user) and whether the user or
network side is on another machine; set those appropriately in the
dissector routines that call it.  To set those flags:

	in the routine that handles WTAP_ENCAP_LAPD, check the direction
	flags in pinfo->rec->rec_header.packet_header.pack_flags;

	in the routine that handles WTAP_ENCAP_LINUX_LAPD, check the SLL
	header;

	in the routine that's called from the ISDN dissector and other
	dissectors that can supply an ISDN pseudo-header, check the
	struct isdn_phdr passed to it via the data argument;

	for the routine that's to be called from L2TP pseudowire type
	and SCTP dissector tables, pass nothing, as there's currently
	no direction indication supplied - if that information is
	available from the encapsulating protocol in some fashion, we
	should make changes to supply that information.

Have the AudioCodes Trunk trace protocol dissector call the
LAPD-with-pseudoheader dissector, handing it an ISDN pseudo-header with
a direction indication from the direction field (and a channel of 0 to
indicate the D channel).

Have the Ascend text dump reader in libwiretap use WTAP_ENCAP_ASCEND for
all packets, even Ethernet and ISDN packets, and have the Ascend text
dump dissector handle that, calling the "no FCS" version of the Ethernet
dissector and calling the LAPD-with-pseudoheader dissector with a
pseudo-header filled in with the direction (and a channel of 0).

Have the Catapult DCT 2000 text dump dissector call the
LAPD-with-pseudoheader dissector with the pseudo-header supplied by
libwireshark.

Have the V5 envelope function frame get its ISDN pseudo-header from its
data argument, and call the LAPD-with-pseudoheader dissector with that
pseudo-header.

Have the ISDN dissector treat its data argument as pointing to the ISDN
pseudo-header, rather than assuming it's the one in
pinfo->pseudo_header->isdn - the latter is the one supplied by
libwiretap, but there's no guarantee that an ISDN pseudo-header was
supplied by libwiretap, as the lowest-level protocol layer might not
have been ISDN.

Change-Id: I9f702b879bbc3fb42bcb43c28f797bfc327562c6
Reviewed-on: https://code.wireshark.org/review/37953
Petri-Dish: Guy Harris <gharris@sonic.net>
Tested-by: Petri Dish Buildbot
Reviewed-by: Guy Harris <gharris@sonic.net>
2020-07-25 18:31:34 +00:00

198 lines
6 KiB
C
Raw Blame History

/* packet-ascend.c
* Routines for decoding Lucent/Ascend packet traces
*
* Wireshark - Network traffic analyzer
* By Gerald Combs <gerald@wireshark.org>
*
* SPDX-License-Identifier: GPL-2.0-or-later
*/
#include "config.h"
#include <epan/packet.h>
#include <wiretap/wtap.h>
void proto_register_ascend(void);
void proto_reg_handoff_ascend(void);
static int proto_ascend = -1;
static int hf_link_type = -1;
static int hf_session_id = -1;
static int hf_called_number = -1;
static int hf_chunk = -1;
static int hf_task = -1;
static int hf_user_name = -1;
static gint ett_raw = -1;
static const value_string encaps_vals[] = {
{ASCEND_PFX_WDS_X, "PPP Transmit" },
{ASCEND_PFX_WDS_R, "PPP Receive" },
{ASCEND_PFX_WDD, "Ethernet triggering dialout"},
{ASCEND_PFX_ISDN_X, "ISDN Transmit" },
{ASCEND_PFX_ISDN_R, "ISDN Receive" },
{ASCEND_PFX_ETHER, "Ethernet" },
{0, NULL }
};
static dissector_handle_t eth_withoutfcs_handle;
static dissector_handle_t ppp_hdlc_handle;
static dissector_handle_t lapd_phdr_handle;
static int
dissect_ascend(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_)
{
proto_tree *fh_tree;
proto_item *ti, *hidden_item;
union wtap_pseudo_header *pseudo_header = pinfo->pseudo_header;
struct isdn_phdr isdn;
/* load the top pane info. This should be overwritten by
the next protocol in the stack */
col_set_str(pinfo->cinfo, COL_RES_DL_SRC, "N/A");
col_set_str(pinfo->cinfo, COL_RES_DL_DST, "N/A");
col_set_str(pinfo->cinfo, COL_PROTOCOL, "N/A");
col_set_str(pinfo->cinfo, COL_INFO, "Lucent/Ascend packet trace");
/* If this is a transmitted or received PPP frame, set the PPP direction. */
switch (pseudo_header->ascend.type) {
case ASCEND_PFX_WDS_X:
pinfo->p2p_dir = P2P_DIR_SENT;
break;
case ASCEND_PFX_WDS_R:
pinfo->p2p_dir = P2P_DIR_RECV;
break;
}
/* populate a tree in the second pane with the status of the link
layer (ie none) */
if(tree) {
ti = proto_tree_add_protocol_format(tree, proto_ascend, tvb, 0, 0,
"Lucent/Ascend packet trace");
fh_tree = proto_item_add_subtree(ti, ett_raw);
proto_tree_add_uint(fh_tree, hf_link_type, tvb, 0, 0,
pseudo_header->ascend.type);
switch (pseudo_header->ascend.type) {
case ASCEND_PFX_WDD:
/* Ethernet packet forcing a call */
proto_tree_add_string(fh_tree, hf_called_number, tvb, 0, 0,
pseudo_header->ascend.call_num);
proto_tree_add_uint(fh_tree, hf_chunk, tvb, 0, 0,
pseudo_header->ascend.chunk);
hidden_item = proto_tree_add_uint(fh_tree, hf_session_id, tvb, 0, 0, 0);
proto_item_set_hidden(hidden_item);
break;
case ASCEND_PFX_WDS_X:
case ASCEND_PFX_WDS_R:
/* wandsession data */
proto_tree_add_string(fh_tree, hf_user_name, tvb, 0, 0,
pseudo_header->ascend.user);
proto_tree_add_uint(fh_tree, hf_session_id, tvb, 0, 0,
pseudo_header->ascend.sess);
hidden_item = proto_tree_add_uint(fh_tree, hf_chunk, tvb, 0, 0, 0);
proto_item_set_hidden(hidden_item);
break;
default:
break;
}
proto_tree_add_uint(fh_tree, hf_task, tvb, 0, 0, pseudo_header->ascend.task);
}
switch (pseudo_header->ascend.type) {
case ASCEND_PFX_WDS_X:
case ASCEND_PFX_WDS_R:
call_dissector(ppp_hdlc_handle, tvb, pinfo, tree);
break;
case ASCEND_PFX_WDD:
case ASCEND_PFX_ETHER:
call_dissector(eth_withoutfcs_handle, tvb, pinfo, tree);
break;
case ASCEND_PFX_ISDN_X:
isdn.uton = TRUE;
isdn.channel = 0;
call_dissector_with_data(lapd_phdr_handle, tvb, pinfo, tree, &isdn);
break;
case ASCEND_PFX_ISDN_R:
isdn.uton = FALSE;
isdn.channel = 0;
call_dissector_with_data(lapd_phdr_handle, tvb, pinfo, tree, &isdn);
break;
default:
break;
}
return tvb_captured_length(tvb);
}
void
proto_register_ascend(void)
{
static hf_register_info hf[] = {
{ &hf_link_type,
{ "Link type", "ascend.type", FT_UINT32, BASE_DEC, VALS(encaps_vals), 0x0,
NULL, HFILL }},
{ &hf_session_id,
{ "Session ID", "ascend.sess", FT_UINT32, BASE_DEC, NULL, 0x0,
NULL, HFILL }},
{ &hf_called_number,
{ "Called number", "ascend.number", FT_STRING, BASE_NONE, NULL, 0x0,
NULL, HFILL }},
{ &hf_chunk,
{ "WDD Chunk", "ascend.chunk", FT_UINT32, BASE_HEX, NULL, 0x0,
NULL, HFILL }},
{ &hf_task,
{ "Task", "ascend.task", FT_UINT32, BASE_HEX, NULL, 0x0,
NULL, HFILL }},
{ &hf_user_name,
{ "User name", "ascend.user", FT_STRING, BASE_NONE, NULL, 0x0,
NULL, HFILL }},
};
static gint *ett[] = {
&ett_raw,
};
proto_ascend = proto_register_protocol("Lucent/Ascend debug output",
"Lucent/Ascend", "ascend");
proto_register_field_array(proto_ascend, hf, array_length(hf));
proto_register_subtree_array(ett, array_length(ett));
}
void
proto_reg_handoff_ascend(void)
{
dissector_handle_t ascend_handle;
/*
* Get handles for the Ethernet, PPP-in-HDLC-like-framing, and
* LAPD-with-pseudoheader dissectors.
*/
eth_withoutfcs_handle = find_dissector_add_dependency("eth_withoutfcs", proto_ascend);
ppp_hdlc_handle = find_dissector_add_dependency("ppp_hdlc", proto_ascend);
lapd_phdr_handle = find_dissector_add_dependency("lapd-phdr", proto_ascend);
ascend_handle = create_dissector_handle(dissect_ascend, proto_ascend);
dissector_add_uint("wtap_encap", WTAP_ENCAP_ASCEND, ascend_handle);
}
/*
* Editor modelines - https://www.wireshark.org/tools/modelines.html
*
* Local Variables:
* c-basic-offset: 2
* tab-width: 8
* indent-tabs-mode: nil
* End:
*
* ex: set shiftwidth=2 tabstop=8 expandtab:
* :indentSize=2:tabSize=8:noTabs=true:
*/
Reference in a new issue View git blame Copy permalink