wireshark/plugins/docsis/packet-rngrsp.c

279 lines
7.7 KiB
C

/* packet-rngrsp.c
* Routines for Ranging Response Message dissection
* Copyright 2002, Anand V. Narwani <anand[AT]narwani.org>
*
* 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>
#include <epan/exceptions.h>
#define RNGRSP_TIMING 1
#define RNGRSP_PWR_LEVEL_ADJ 2
#define RNGRSP_OFFSET_FREQ_ADJ 3
#define RNGRSP_TRANSMIT_EQ_ADJ 4
#define RNGRSP_RANGING_STATUS 5
#define RNGRSP_DOWN_FREQ_OVER 6
#define RNGRSP_UP_CHID_OVER 7
void proto_register_docsis_rngrsp(void);
void proto_reg_handoff_docsis_rngrsp(void);
/* Initialize the protocol and registered fields */
static int proto_docsis_rngrsp = -1;
static int hf_docsis_rngrsp_upstream_chid = -1;
static int hf_docsis_rngrsp_sid = -1;
static int hf_docsis_rngrsp_timing_adj = -1;
static int hf_docsis_rngrsp_power_adj = -1;
static int hf_docsis_rngrsp_freq_adj = -1;
static int hf_docsis_rngrsp_xmit_eq_adj = -1;
static int hf_docsis_rngrsp_ranging_status = -1;
static int hf_docsis_rngrsp_down_freq_over = -1;
static int hf_docsis_rngrsp_upstream_ch_over = -1;
static const value_string rng_stat_vals[] = {
{1, "Continue"},
{2, "Abort"},
{3, "Success"},
{0, NULL}
};
/* Initialize the subtree pointers */
static gint ett_docsis_rngrsp = -1;
/* Code to actually dissect the packets */
static void
dissect_rngrsp (tvbuff_t * tvb, packet_info * pinfo, proto_tree * tree)
{
proto_item *it;
proto_tree *rngrsp_tree;
guint8 tlvtype, tlvlen;
int pos;
gint length;
guint8 upchid;
guint16 sid;
gint8 pwr;
gint32 tim;
sid = tvb_get_ntohs (tvb, 0);
upchid = tvb_get_guint8 (tvb, 2);
if (upchid > 0)
col_add_fstr (pinfo->cinfo, COL_INFO,
"Ranging Response: SID = %u, Upstream Channel = %u (U%u)",
sid, upchid, upchid - 1);
else
col_add_fstr (pinfo->cinfo, COL_INFO,
"Ranging Response: SID = %u, Telephony Return", sid);
if (tree)
{
it =
proto_tree_add_protocol_format (tree, proto_docsis_rngrsp, tvb, 0, -1,
"Ranging Response");
rngrsp_tree = proto_item_add_subtree (it, ett_docsis_rngrsp);
proto_tree_add_item (rngrsp_tree, hf_docsis_rngrsp_sid, tvb, 0, 2,
ENC_BIG_ENDIAN);
proto_tree_add_item (rngrsp_tree, hf_docsis_rngrsp_upstream_chid, tvb,
2, 1, ENC_BIG_ENDIAN);
length = tvb_reported_length_remaining (tvb, 0);
pos = 3;
while (pos < length)
{
tlvtype = tvb_get_guint8 (tvb, pos++);
tlvlen = tvb_get_guint8 (tvb, pos++);
switch (tlvtype)
{
case RNGRSP_TIMING:
if (tlvlen == 4)
{
tim = tvb_get_ntohl (tvb, pos);
proto_tree_add_int (rngrsp_tree,
hf_docsis_rngrsp_timing_adj, tvb, pos,
tlvlen, tim);
}
else
{
THROW (ReportedBoundsError);
}
break;
case RNGRSP_PWR_LEVEL_ADJ:
if (tlvlen == 1)
{
pwr = tvb_get_guint8 (tvb, pos);
proto_tree_add_int (rngrsp_tree, hf_docsis_rngrsp_power_adj,
tvb, pos, tlvlen, pwr);
}
else
{
THROW (ReportedBoundsError);
}
break;
case RNGRSP_OFFSET_FREQ_ADJ:
if (tlvlen == 2)
{
proto_tree_add_item (rngrsp_tree, hf_docsis_rngrsp_freq_adj,
tvb, pos, tlvlen, ENC_BIG_ENDIAN);
}
else
{
THROW (ReportedBoundsError);
}
break;
case RNGRSP_TRANSMIT_EQ_ADJ:
proto_tree_add_item (rngrsp_tree, hf_docsis_rngrsp_xmit_eq_adj,
tvb, pos, tlvlen, ENC_NA);
break;
case RNGRSP_RANGING_STATUS:
if (tlvlen == 1)
proto_tree_add_item (rngrsp_tree,
hf_docsis_rngrsp_ranging_status, tvb,
pos, tlvlen, ENC_BIG_ENDIAN);
else
{
THROW (ReportedBoundsError);
}
break;
case RNGRSP_DOWN_FREQ_OVER:
if (tlvlen == 4)
proto_tree_add_item (rngrsp_tree,
hf_docsis_rngrsp_down_freq_over, tvb,
pos, tlvlen, ENC_BIG_ENDIAN);
else
{
THROW (ReportedBoundsError);
}
break;
case RNGRSP_UP_CHID_OVER:
if (tlvlen == 1)
proto_tree_add_item (rngrsp_tree,
hf_docsis_rngrsp_upstream_ch_over, tvb,
pos, tlvlen, ENC_BIG_ENDIAN);
else
{
THROW (ReportedBoundsError);
}
break;
} /* switch(tlvtype) */
pos = pos + tlvlen;
} /* while (pos < length) */
} /* if (tree) */
}
/* Register the protocol with Wireshark */
/* this format is require because a script is used to build the C function
that calls all the protocol registration.
*/
void
proto_register_docsis_rngrsp (void)
{
/* Setup list of header fields See Section 1.6.1 for details*/
static hf_register_info hf[] = {
{&hf_docsis_rngrsp_sid,
{"Service Identifier", "docsis_rngrsp.sid",
FT_UINT16, BASE_DEC, NULL, 0x0,
NULL, HFILL}
},
{&hf_docsis_rngrsp_upstream_chid,
{"Upstream Channel ID", "docsis_rngrsp.upchid",
FT_UINT8, BASE_DEC, NULL, 0x0,
NULL, HFILL}
},
{&hf_docsis_rngrsp_timing_adj,
{"Timing Adjust (6.25us/64)", "docsis_rngrsp.timingadj",
FT_INT32, BASE_DEC, NULL, 0x0,
"Timing Adjust", HFILL}
},
{&hf_docsis_rngrsp_power_adj,
{"Power Level Adjust (0.25dB units)", "docsis_rngrsp.poweradj",
FT_INT8, BASE_DEC, NULL, 0x0,
"Power Level Adjust", HFILL}
},
{&hf_docsis_rngrsp_freq_adj,
{"Offset Freq Adjust (Hz)", "docsis_rngrsp.freqadj",
FT_INT16, BASE_DEC, NULL, 0x0,
"Frequency Adjust", HFILL}
},
{&hf_docsis_rngrsp_xmit_eq_adj,
{"Transmit Equalisation Adjust", "docsis_rngrsp.xmit_eq_adj",
FT_BYTES, BASE_NONE, NULL, 0x0,
"Timing Equalisation Adjust", HFILL}
},
{&hf_docsis_rngrsp_ranging_status,
{"Ranging Status", "docsis_rngrsp.rng_stat",
FT_UINT8, BASE_DEC, VALS (rng_stat_vals), 0x0,
NULL, HFILL}
},
{&hf_docsis_rngrsp_down_freq_over,
{"Downstream Frequency Override (Hz)", "docsis_rngrsp.freq_over",
FT_UINT32, BASE_DEC, NULL, 0x0,
"Downstream Frequency Override", HFILL}
},
{&hf_docsis_rngrsp_upstream_ch_over,
{"Upstream Channel ID Override", "docsis_rngrsp.chid_override",
FT_UINT8, BASE_DEC, NULL, 0x0,
NULL, HFILL}
},
};
/* Setup protocol subtree array */
static gint *ett[] = {
&ett_docsis_rngrsp,
};
/* Register the protocol name and description */
proto_docsis_rngrsp = proto_register_protocol ("DOCSIS Ranging Response",
"DOCSIS RNG-RSP",
"docsis_rngrsp");
/* Required function calls to register the header fields and subtrees used */
proto_register_field_array (proto_docsis_rngrsp, hf, array_length (hf));
proto_register_subtree_array (ett, array_length (ett));
register_dissector ("docsis_rngrsp", dissect_rngrsp, proto_docsis_rngrsp);
}
/* If this dissector uses sub-dissector registration add a registration routine.
This format is required because a script is used to find these routines and
create the code that calls these routines.
*/
void
proto_reg_handoff_docsis_rngrsp (void)
{
dissector_handle_t docsis_rngrsp_handle;
docsis_rngrsp_handle = find_dissector ("docsis_rngrsp");
dissector_add_uint ("docsis_mgmt", 0x05, docsis_rngrsp_handle);
}