wireshark/epan/dissectors/packet-pw-oam.c

225 lines
6.5 KiB
C

/* packet-pw-oam.c
*
* Routines for Pseudowire Status for static pseudowires : RFC 6478
*
* (c) Copyright 2012, Krishnamurthy Mayya <krishnamurthymayya@gmail.com>
* Nikitha Malgi <nikitha01@gmail.com>
*
* Wireshark - Network traffic analyzer
* By Gerald Combs <gerald@wireshark.org>
* Copyright 1998 Gerald Combs
*
* 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include "config.h"
#include <epan/packet.h>
void proto_register_pw_oam(void);
void proto_reg_handoff_pw_oam(void);
/* MPLS-TP FM protocol specific variables */
static gint proto_pw_oam = -1;
static gint ett_pw_oam = -1;
static gint ett_pw_oam_flags = -1;
static gint ett_pw_oam_tlv_tree = -1;
static int hf_pw_oam_tlv_reserved = -1;
static int hf_pw_oam_tlv_type = -1;
static int hf_pw_oam_total_tlv_len = -1;
static int hf_pw_oam_code = -1;
static int hf_pw_oam_flags = -1;
static int hf_pw_oam_flags_a = -1;
static int hf_pw_oam_refresh_timer = -1;
static int hf_pw_oam_tlv_len = -1;
static const value_string pw_oam_code[] = {
{0x00000002, "Local Attachment Circuit(ingress) Receive Fault"},
{0x00000004, "Local Attachment Circuit(egress) Transmit Fault"},
{0x00000020, "PW Forwarding Standby"},
{0x00000040, "Request Switchover to this PW"},
{0, NULL}
};
/* PW-Status TLV dissector */
static void
dissect_pw_status_tlv (tvbuff_t *tvb, proto_tree *tree, gint offset)
{
proto_item *ti;
proto_tree *pw_oam_tlv_tree;
ti = proto_tree_add_protocol_format (tree, proto_pw_oam, tvb, offset, 8,
"Pseudo-Wire Status TLV");
if (!tree)
return;
pw_oam_tlv_tree = proto_item_add_subtree (ti, ett_pw_oam_tlv_tree);
proto_tree_add_item (pw_oam_tlv_tree, hf_pw_oam_tlv_reserved, tvb, offset,
2, ENC_BIG_ENDIAN);
proto_tree_add_item (pw_oam_tlv_tree, hf_pw_oam_tlv_type, tvb, offset,
2, ENC_BIG_ENDIAN);
offset = offset + 2;
proto_tree_add_item (pw_oam_tlv_tree, hf_pw_oam_tlv_len, tvb, offset,
2, ENC_BIG_ENDIAN);
offset = offset + 2;
proto_tree_add_item (pw_oam_tlv_tree, hf_pw_oam_code, tvb, offset,
4, ENC_BIG_ENDIAN);
/*offset = offset + 4;*/
return ;
}
/* Dissector for PW OAM protocol: RFC 6478 */
static int
dissect_pw_oam(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_)
{
proto_item *ti = NULL, *ti_flags = NULL;
proto_tree *pw_oam_tree = NULL, *pw_oam_flags = NULL;
guint8 offset = 0;
guint16 pw_tlv_type = 0;
col_set_str(pinfo->cinfo, COL_PROTOCOL, "PW OAM");
col_clear(pinfo->cinfo, COL_INFO);
if (!tree)
return tvb_captured_length(tvb);
ti = proto_tree_add_item(tree, proto_pw_oam, tvb, 0, -1, ENC_NA);
pw_oam_tree = proto_item_add_subtree (ti, ett_pw_oam);
/* Refresh-Timer field */
proto_tree_add_item (pw_oam_tree, hf_pw_oam_refresh_timer, tvb, offset,
2, ENC_BIG_ENDIAN);
offset = offset + 2;
/* Total-TLV length */
proto_tree_add_item (pw_oam_tree, hf_pw_oam_total_tlv_len, tvb, offset,
1, ENC_BIG_ENDIAN);
offset = offset + 1;
/* Flags field */
ti_flags = proto_tree_add_item (pw_oam_tree, hf_pw_oam_flags, tvb,
offset, 1, ENC_BIG_ENDIAN);
pw_oam_flags = proto_item_add_subtree(ti_flags, ett_pw_oam_flags);
proto_tree_add_item (pw_oam_flags, hf_pw_oam_flags_a, tvb, offset, 1, ENC_BIG_ENDIAN);
offset = offset + 1;
pw_tlv_type = tvb_get_ntohs (tvb, offset);
/* TLVs */
switch (pw_tlv_type)
{
/* The switch cases below have to be based on the LDP-name space.
http://www.iana.org/assignments/ldp-namespaces/ldp-namespaces.xml */
case 0x096A: /* PW-Status TLV */
dissect_pw_status_tlv (tvb, tree, offset);
break;
default:
break;
}
return tvb_captured_length(tvb);
}
void
proto_register_pw_oam(void)
{
static hf_register_info hf[] = {
{&hf_pw_oam_refresh_timer,
{"Refresh-Timer", "pw_oam.refresh-timer", FT_UINT16,
BASE_HEX, NULL, 0x0, NULL, HFILL }},
{&hf_pw_oam_total_tlv_len,
{"TLV Length", "pw_oam.total-tlv-len", FT_UINT8,
BASE_HEX, NULL, 0x0, NULL, HFILL }},
{&hf_pw_oam_flags,
{"Flags", "pw_oam.flags", FT_UINT8,
BASE_HEX, NULL, 0x0000, "OAM Flags", HFILL }},
{&hf_pw_oam_flags_a,
{"Acknowledgement", "pw_oam.flags_a",
FT_BOOLEAN, 8, NULL, 0x0080, "ACK bit", HFILL}
},
{&hf_pw_oam_tlv_reserved,
{"Reserved", "pw_oam.tlv-reserved",
FT_UINT16, BASE_HEX, NULL, 0xC000, NULL, HFILL}
},
{&hf_pw_oam_tlv_type,
{"TLV Type", "pw_oam.tlv-type",
FT_UINT16, BASE_HEX, NULL, 0x3FFF, NULL, HFILL}
},
{&hf_pw_oam_tlv_len,
{"TLV Length", "pw_oam.tlv-len",
FT_UINT16, BASE_HEX, NULL, 0x00, NULL, HFILL}
},
{&hf_pw_oam_code,
{"Status code", "pw_oam.code", FT_UINT16,
BASE_HEX, VALS(pw_oam_code), 0x0, "PW Status Code", HFILL }
},
};
static gint *ett[] = {
&ett_pw_oam,
&ett_pw_oam_tlv_tree,
&ett_pw_oam_flags,
};
proto_pw_oam =
proto_register_protocol("Pseudo-Wire OAM", "PW-OAM "
"Pseudo-Wire OAM Protocol",
"pw_oam");
proto_register_field_array (proto_pw_oam, hf, array_length(hf));
proto_register_subtree_array (ett, array_length(ett));
}
void
proto_reg_handoff_pw_oam(void)
{
dissector_handle_t pw_oam_handle;
pw_oam_handle = create_dissector_handle( dissect_pw_oam, proto_pw_oam );
dissector_add_uint("pwach.channel_type", 0x0027, pw_oam_handle); /* KM: MPLSTP PW-OAM, RFC 6478 */
}
/*
* Editor modelines - http://www.wireshark.org/tools/modelines.html
*
* Local variables:
* c-basic-offset: 2
* tab-width: 8
* indent-tabs-mode: nil
* End:
*
* vi: set shiftwidth=2 tabstop=8 expandtab:
* :indentSize=2:tabSize=8:noTabs=true:
*/