wireshark/epan/dissectors/packet-avsp.c

315 lines
10 KiB
C

/* packet-avsp.c
* Arista Vendor Specific ethertype Protocol (AVSP)
*
* Copyright (c) 2018 by Arista Networks
* Author: Nikhil AP <nikhilap@arista.com>
*
* Wireshark - Network traffic analyzer
* By Gerald Combs <gerald@wireshark.org>
* Copyright 1999 Gerald Combs
*
* SPDX-License-Identifier: GPL-2.0-or-later
*/
/* Arista Vendor-Specific EtherType Protocol Identifier
*
* Arista applied for, and received the assignment of, a vendor-specific EtherType Protocol Identifier in May of 2016. Details below:
*
* Ethertype number is: D28B
* Issue date is: May 12, 2016
*
* Arista Subtype 0x01 is Timestamp L2 Header
*
* The timestamp L2 header consist of the following fields:
*
* Arista EtherType (0xD28B)
* Two-byte protocol subtype of 0x1
* Two-byte protocol version: 0x10 for 64-bit timestamp and 0x20 for 48-bit timestamp
* UTC timestamp value in IEEE 1588 time of day format (either 64-bit or 48-bit) with the lower 32-bits representing nanoseconds and upper bits representing seconds.
*/
#include "config.h"
#include <epan/packet.h>
#include <epan/etypes.h>
#include <epan/expert.h>
#define ARISTA_TIMESTAMP_SUBTYPE 0x01
#define ARISTA_TIMESTAMP_64_TAI 0x10
#define ARISTA_TIMESTAMP_64_UTC 0x110
#define ARISTA_TIMESTAMP_48_TAI 0x20
#define ARISTA_TIMESTAMP_48_UTC 0x120
void proto_reg_handoff_avsp(void);
void proto_register_avsp(void);
static int proto_avsp = -1;
/* sub trees */
static gint ett_avsp = -1;
static gint ett_avsp_ts_48 = -1;
static gint ett_avsp_ts_64 = -1;
/* avsp variables */
static int hf_avsp_sub_type = -1;
static int hf_avsp_ts_version = -1;
static int hf_avsp_ts_64_tai = -1;
static int hf_avsp_ts_64_utc = -1;
static int hf_avsp_ts_64_sec = -1;
static int hf_avsp_ts_64_ns = -1;
static int hf_avsp_ts_48_tai = -1;
static int hf_avsp_ts_48_utc = -1;
static int hf_avsp_ts_48_sec = -1;
static int hf_avsp_ts_48_ns = -1;
static int hf_avsp_etype = -1;
static int hf_avsp_trailer = -1;
static dissector_handle_t ethertype_handle;
static expert_field ei_avsp_ts_unknown_version = EI_INIT;
static const value_string arista_subtype[] = {
{ARISTA_TIMESTAMP_SUBTYPE, "timestamp"},
{0, NULL}
};
static const value_string ts_versions[] = {
{ARISTA_TIMESTAMP_64_TAI, "Version 1"},
{ARISTA_TIMESTAMP_64_UTC, "Version 11"},
{ARISTA_TIMESTAMP_48_TAI, "Version 2"},
{ARISTA_TIMESTAMP_48_UTC, "Version 12"},
{0, NULL}
};
static ei_register_info ei[] = {
{ &ei_avsp_ts_unknown_version, { "avsp.ts.unknown_version", PI_SEQUENCE, PI_WARN, "Unknown timestamp version", EXPFILL }},
};
static int
dissect_avsp(tvbuff_t * tvb, packet_info * pinfo, proto_tree * tree, void *data _U_)
{
guint8 offset = 0;
int version, subtype;
/* col_set_str() function is used to set the column string */
col_set_str(pinfo->cinfo, COL_PROTOCOL, "AVSP");
col_clear(pinfo->cinfo, COL_INFO);
proto_item *ti = NULL;
proto_tree *avsp_tree = NULL, *avsp_48_tree = NULL, *avsp_64_tree;
/* Adding Items and Values to the Protocol Tree */
ti = proto_tree_add_item(tree, proto_avsp, tvb, 0, -1,
ENC_NA);
avsp_tree = proto_item_add_subtree(ti, ett_avsp);
/* adding each item to avsp */
proto_tree_add_item_ret_uint(avsp_tree, hf_avsp_sub_type, tvb,
offset, 2, ENC_BIG_ENDIAN, &subtype);
offset += 2;
if (subtype == ARISTA_TIMESTAMP_SUBTYPE) {
proto_tree_add_item_ret_uint(avsp_tree, hf_avsp_ts_version, tvb, offset,
2, ENC_BIG_ENDIAN, &version);
offset += 2;
switch (version) {
case ARISTA_TIMESTAMP_64_TAI:
ti = proto_tree_add_item(avsp_tree, hf_avsp_ts_64_tai, tvb, 0, -1,
ENC_NA);
avsp_64_tree = proto_item_add_subtree(ti, ett_avsp);
col_add_fstr(pinfo->cinfo, COL_INFO, "64bit TAI timestamp");
proto_tree_add_item(avsp_64_tree, hf_avsp_ts_64_sec, tvb, offset,
4, ENC_BIG_ENDIAN);
offset += 4;
proto_tree_add_item(avsp_64_tree, hf_avsp_ts_64_ns, tvb, offset,
4, ENC_BIG_ENDIAN);
offset += 4;
break;
case ARISTA_TIMESTAMP_64_UTC:
ti = proto_tree_add_item(avsp_tree, hf_avsp_ts_64_utc, tvb, 0, -1,
ENC_NA);
avsp_64_tree = proto_item_add_subtree(ti, ett_avsp);
col_add_fstr(pinfo->cinfo, COL_INFO, "64bit UTC timestamp");
proto_tree_add_item(avsp_64_tree, hf_avsp_ts_64_sec, tvb, offset,
4, ENC_BIG_ENDIAN);
offset += 4;
proto_tree_add_item(avsp_64_tree, hf_avsp_ts_64_ns, tvb, offset,
4, ENC_BIG_ENDIAN);
offset += 4;
break;
case ARISTA_TIMESTAMP_48_TAI:
ti = proto_tree_add_item(avsp_tree, hf_avsp_ts_48_tai, tvb, 0, -1,
ENC_NA);
avsp_48_tree = proto_item_add_subtree(ti, ett_avsp);
col_add_fstr(pinfo->cinfo, COL_INFO, "48bit TAI timestamp");
proto_tree_add_item(avsp_48_tree, hf_avsp_ts_48_sec, tvb, offset,
2, ENC_BIG_ENDIAN);
offset += 2;
proto_tree_add_item(avsp_48_tree, hf_avsp_ts_48_ns, tvb, offset,
4, ENC_BIG_ENDIAN);
offset += 4;
break;
case ARISTA_TIMESTAMP_48_UTC:
ti = proto_tree_add_item(avsp_tree, hf_avsp_ts_48_utc, tvb, 0, -1,
ENC_NA);
avsp_48_tree = proto_item_add_subtree(ti, ett_avsp);
col_add_fstr(pinfo->cinfo, COL_INFO, "48bit UTC timestamp");
proto_tree_add_item(avsp_48_tree, hf_avsp_ts_48_sec, tvb, offset,
2, ENC_BIG_ENDIAN);
offset += 2;
proto_tree_add_item(avsp_48_tree, hf_avsp_ts_48_ns, tvb, offset,
4, ENC_BIG_ENDIAN);
offset += 4;
break;
default:
expert_add_info_format(pinfo, ti, &ei_avsp_ts_unknown_version,
"Unknown timestamp version: 0x%0x", version);
return tvb_captured_length(tvb);
}
}
guint16 encap_proto;
encap_proto = tvb_get_ntohs(tvb, offset);
proto_tree_add_uint(avsp_tree, hf_avsp_etype, tvb, offset, 2, encap_proto);
offset += 2;
ethertype_data_t ethertype_data;
ethertype_data.etype = encap_proto;
ethertype_data.payload_offset = offset;
ethertype_data.fh_tree = avsp_tree;
ethertype_data.trailer_id = hf_avsp_trailer;
ethertype_data.fcs_len = 0;
call_dissector_with_data(ethertype_handle, tvb, pinfo, tree, &ethertype_data);
return tvb_captured_length(tvb);
}
void proto_reg_handoff_avsp(void)
{
/* the handle for the dynamic dissector */
dissector_handle_t avsp_handle;
avsp_handle =
create_dissector_handle(dissect_avsp, proto_avsp);
dissector_add_uint("ethertype", ETHERTYPE_AVSP, avsp_handle);
ethertype_handle = find_dissector_add_dependency("ethertype", proto_avsp);
}
void proto_register_avsp(void)
{
/* Field Registration */
static hf_register_info hf[] = {
/* For avsp */
{&hf_avsp_sub_type,
{"Sub Type", "avsp.sub_type",
FT_UINT16, BASE_DEC,
VALS(arista_subtype), 0x0,
NULL, HFILL}
},
{&hf_avsp_ts_version,
{"Version", "avsp.ver",
FT_UINT16, BASE_HEX,
VALS(ts_versions), 0x0,
NULL, HFILL}
},
{&hf_avsp_ts_64_tai,
{"Timestamp (TAI)", "avsp.64ts",
FT_NONE, BASE_NONE,
NULL, 0x0,
NULL, HFILL}
},
{&hf_avsp_ts_64_utc,
{"Timestamp (UTC)", "avsp.64ts",
FT_NONE, BASE_NONE,
NULL, 0x0,
NULL, HFILL}
},
{&hf_avsp_ts_64_sec,
{"Seconds", "avsp.64sec",
FT_UINT32, BASE_DEC,
NULL, 0x0,
NULL, HFILL}
},
{&hf_avsp_ts_64_ns,
{"Nanoseconds", "avsp.64ns",
FT_UINT32, BASE_DEC,
NULL, 0x0,
NULL, HFILL}
},
{&hf_avsp_ts_48_tai,
{"Timestamp (TAI)", "avsp.48ts",
FT_NONE, BASE_NONE,
NULL, 0x0,
NULL, HFILL}
},
{&hf_avsp_ts_48_utc,
{"Timestamp (UTC)", "avsp.48ts",
FT_NONE, BASE_NONE,
NULL, 0x0,
NULL, HFILL}
},
{&hf_avsp_ts_48_sec,
{"Seconds", "avsp.48sec",
FT_UINT16, BASE_DEC,
NULL, 0x0,
NULL, HFILL}
},
{&hf_avsp_ts_48_ns,
{"Nanoseconds", "avsp.48ns",
FT_UINT32, BASE_DEC,
NULL, 0x0,
NULL, HFILL}
},
{&hf_avsp_etype,
{"Type", "avsp.etype",
FT_UINT16, BASE_HEX,
VALS(etype_vals), 0x0,
"Ethertype", HFILL}
},
{&hf_avsp_trailer,
{"Trailer", "avsp.trailer",
FT_BYTES, BASE_NONE,
NULL, 0x0,
"AVSP Trailer", HFILL}
},
};
/* Setup protocol subtree array */
static gint *ett[] = {
&ett_avsp, /* main avsp tree */
&ett_avsp_ts_48, /* subtree above for 48 bit timestamp */
&ett_avsp_ts_64, /* subtree above for 64 bit timestamp */
};
/* registering the avsp protocol with 3 names */
proto_avsp = proto_register_protocol("Arista Vendor Specific Protocol",
"avsp",
"avsp"
);
/* Register header fields and subtrees. */
proto_register_field_array(proto_avsp, hf, array_length(hf));
/* To register subtree types, pass an array of pointers */
proto_register_subtree_array(ett, array_length(ett));
expert_register_field_array(expert_register_protocol(proto_avsp),
ei, array_length(ei));
}
/*
* Editor modelines - https://www.wireshark.org/tools/modelines.html
*
* Local variables:
* c-basic-offset: 4
* tab-width: 8
* indent-tabs-mode: nil
* End:
*
* vi: set shiftwidth=4 tabstop=8 expandtab:
* :indentSize=4:tabSize=8:noTabs=true:
*/