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wireshark/epan/dissectors/packet-pppoe.c
Jeff Morriss 1ddf33b720 From Edward J. Paradise via 
https://bugs.wireshark.org/bugzilla/show_bug.cgi?id=2693 :

The rfc4938bis draft extends the Point-to-Point over Ethernet (PPPoE) protocol
with an optional credit-based flow control mechanism and an optional Link
Quality Metric report.  These optional extensions improve the performance of
PPPoE over media with variable bandwidth and limited buffering, such as mobile
point-to-point radio links.

Support for rfc4938 already exists in wireshark, but rfc4938bis specifies a new
credit scale factor TLV and the use of the reserved field of the PADQ to
specify max and current data-rate scaling.

svn path=/trunk/; revision=25768
2008-07-19 15:04:20 +00:00

777 lines
26 KiB
C
Raw Blame History

/* packet-pppoe.c
* Routines for PPP Over Ethernet (PPPoE) packet disassembly (RFC2516)
* Up to date with http://www.iana.org/assignments/pppoe-parameters (2007-07-10)
*
* $Id$
*
* 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#include <glib.h>
#include <epan/packet.h>
#include <epan/emem.h>
#include <epan/strutil.h>
#include <epan/etypes.h>
#include <epan/prefs.h>
#include <epan/expert.h>
static int proto_pppoed = -1;
/* Common to session and discovery protocols */
static gint hf_pppoe_version = -1;
static gint hf_pppoe_type = -1;
static gint hf_pppoe_code = -1;
static gint hf_pppoe_session_id = -1;
static gint hf_pppoe_payload_length = -1;
/* Discovery protocol fields */
static gint hf_pppoed_tags = -1;
static gint hf_pppoed_tag = -1;
static gint hf_pppoed_tag_length = -1;
static gint hf_pppoed_tag_unknown_data = -1;
static gint hf_pppoed_tag_service_name = -1;
static gint hf_pppoed_tag_ac_name = -1;
static gint hf_pppoed_tag_host_uniq = -1;
static gint hf_pppoed_tag_ac_cookie = -1;
static gint hf_pppoed_tag_vendor_id = -1;
static gint hf_pppoed_tag_vendor_unspecified = -1;
static gint hf_pppoed_tag_credits = -1;
static gint hf_pppoed_tag_credits_fcn = -1;
static gint hf_pppoed_tag_credits_bcn = -1;
static gint hf_pppoed_tag_metrics = -1;
static gint hf_pppoed_tag_metrics_r = -1;
static gint hf_pppoed_tag_metrics_rlq = -1;
static gint hf_pppoed_tag_metrics_resource = -1;
static gint hf_pppoed_tag_metrics_latency = -1;
static gint hf_pppoed_tag_metrics_curr_drate = -1;
static gint hf_pppoed_tag_metrics_max_drate = -1;
static gint hf_pppoed_tag_mdr_units = -1;
static gint hf_pppoed_tag_cdr_units = -1;
static gint hf_pppoed_tag_seq_num = -1;
static gint hf_pppoed_tag_cred_scale = -1;
static gint hf_pppoed_tag_relay_session_id = -1;
static gint hf_pppoed_tag_hurl = -1;
static gint hf_pppoed_tag_motm = -1;
static gint hf_pppoed_tag_max_payload = -1;
static gint hf_pppoed_tag_ip_route_add = -1;
static gint hf_pppoed_tag_service_name_error = -1;
static gint hf_pppoed_tag_ac_system_error = -1;
static gint hf_pppoed_tag_generic_error = -1;
static gint ett_pppoed = -1;
static gint ett_pppoed_tags = -1;
static int proto_pppoes = -1;
/* Handle for calling for ppp dissector to handle session data */
static dissector_handle_t ppp_handle;
/* Preference for showing discovery tag values and lengths */
static gboolean global_pppoe_show_tags_and_lengths = FALSE;
#define PPPOE_CODE_SESSION 0x00
#define PPPOE_CODE_PADO 0x07
#define PPPOE_CODE_PADI 0x09
#define PPPOE_CODE_PADG 0x0a
#define PPPOE_CODE_PADC 0x0b
#define PPPOE_CODE_PADQ 0x0c
#define PPPOE_CODE_PADR 0x19
#define PPPOE_CODE_PADS 0x65
#define PPPOE_CODE_PADT 0xa7
#define PPPOE_CODE_PADM 0xd3
#define PPPOE_CODE_PADN 0xd4
#define PPPOE_TAG_EOL 0x0000
#define PPPOE_TAG_SVC_NAME 0x0101
#define PPPOE_TAG_AC_NAME 0x0102
#define PPPOE_TAG_HOST_UNIQ 0x0103
#define PPPOE_TAG_AC_COOKIE 0x0104
#define PPPOE_TAG_VENDOR 0x0105
#define PPPOE_TAG_CREDITS 0x0106
#define PPPOE_TAG_METRICS 0x0107
#define PPPOE_TAG_SEQ_NUM 0x0108
#define PPPOE_TAG_CRED_SCALE 0x0109
#define PPPOE_TAG_RELAY_ID 0x0110
#define PPPOE_TAG_HURL 0x0111
#define PPPOE_TAG_MOTM 0x0112
#define PPPOE_TAG_MAX_PAYLD 0x0120
#define PPPOE_TAG_IP_RT_ADD 0x0121
#define PPPOE_TAG_SVC_ERR 0x0201
#define PPPOE_TAG_AC_ERR 0x0202
#define PPPOE_TAG_GENERIC_ERR 0x0203
#define PPPOE_CDR_MASK 0x06
#define PPPOE_MDR_MASK 0x18
#define PPPOE_RCV_ONLY_MASK 0x01
#define PPPOE_SCALE_KBPS 0x00
#define PPPOE_SCALE_MBPS 0x01
#define PPPOE_SCALE_GBPS 0x02
#define PPPOE_SCALE_TBPS 0x03
static const value_string code_vals[] = {
{PPPOE_CODE_SESSION, "Session Data" },
{PPPOE_CODE_PADO, "Active Discovery Offer (PADO)" },
{PPPOE_CODE_PADI, "Active Discovery Initiation (PADI)" },
{PPPOE_CODE_PADG, "Active Discovery Session-Grant (PADG)" },
{PPPOE_CODE_PADC, "Active Discovery Session-Credit Resp.(PADC)" },
{PPPOE_CODE_PADQ, "Active Discovery Quality (PADQ)" },
{PPPOE_CODE_PADR, "Active Discovery Request (PADR)" },
{PPPOE_CODE_PADS, "Active Discovery Session-confirmation (PADS)"},
{PPPOE_CODE_PADT, "Active Discovery Terminate (PADT)" },
{PPPOE_CODE_PADM, "Active Discovery Message (PADM)" },
{PPPOE_CODE_PADN, "Active Discovery Network (PADN)" },
{0, NULL }
};
static const value_string tag_vals[] = {
{PPPOE_TAG_EOL, "End-Of-List" },
{PPPOE_TAG_SVC_NAME, "Service-Name" },
{PPPOE_TAG_AC_NAME, "AC-Name" },
{PPPOE_TAG_HOST_UNIQ, "Host-Uniq" },
{PPPOE_TAG_AC_COOKIE, "AC-Cookie" },
{PPPOE_TAG_VENDOR, "Vendor-Specific" },
{PPPOE_TAG_CREDITS, "Credits" },
{PPPOE_TAG_METRICS, "Metrics" },
{PPPOE_TAG_SEQ_NUM, "Seqence Number" },
{PPPOE_TAG_CRED_SCALE, "Credit Scale Factor"},
{PPPOE_TAG_RELAY_ID, "Relay-Session-Id" },
{PPPOE_TAG_HURL, "HURL" },
{PPPOE_TAG_MOTM, "MOTM" },
{PPPOE_TAG_MAX_PAYLD, "PPP-Max-Payload" },
{PPPOE_TAG_IP_RT_ADD, "IP Route Add" },
{PPPOE_TAG_SVC_ERR, "Service-Name-Error"},
{PPPOE_TAG_AC_ERR, "AC-System-Error" },
{PPPOE_TAG_GENERIC_ERR,"Generic-Error" },
{0, NULL }
};
const value_string datarate_scale_vals[] = {
{PPPOE_SCALE_KBPS, "kilobits per second"},
{PPPOE_SCALE_MBPS, "megabits per second"},
{PPPOE_SCALE_GBPS, "gigabits per second"},
{PPPOE_SCALE_TBPS, "terabits per second"},
{0, NULL }
};
/* Dissect discovery protocol tags */
static void
dissect_pppoe_tags(tvbuff_t *tvb, packet_info *pinfo, int offset, proto_tree *tree,
int payload_length)
{
guint16 poe_tag;
guint16 poe_tag_length;
int tagstart;
guint16 poe_rsv = 0;
proto_tree *pppoe_tree;
proto_item *ti;
/* Start Decoding Here. */
if (tree)
{
/* Create tags subtree */
ti = proto_tree_add_item(tree, hf_pppoed_tags, tvb, offset, payload_length-6, FALSE);
pppoe_tree = proto_item_add_subtree(ti, ett_pppoed_tags);
tagstart = offset;
/* Loop until all data seen or End-Of-List tag found */
while (tagstart <= payload_length-2)
{
poe_tag = tvb_get_ntohs(tvb, tagstart);
poe_tag_length = tvb_get_ntohs(tvb, tagstart + 2);
/* Tag value and data length */
if (global_pppoe_show_tags_and_lengths)
{
proto_tree_add_item(pppoe_tree, hf_pppoed_tag, tvb, tagstart, 2, FALSE);
proto_tree_add_item(pppoe_tree, hf_pppoed_tag_length, tvb, tagstart+2, 2, FALSE);
}
/* Show tag data */
switch (poe_tag)
{
case PPPOE_TAG_SVC_NAME:
if (poe_tag_length > 0)
{
proto_tree_add_item(pppoe_tree, hf_pppoed_tag_service_name, tvb,
tagstart+4, poe_tag_length, FALSE);
}
break;
case PPPOE_TAG_AC_NAME:
proto_tree_add_item(pppoe_tree, hf_pppoed_tag_ac_name, tvb,
tagstart+4, poe_tag_length, FALSE);
/* Show AC-Name in info column */
if (check_col(pinfo->cinfo, COL_INFO))
{
col_append_fstr(pinfo->cinfo, COL_INFO, " AC-Name='%s'",
tvb_get_ephemeral_string(tvb, tagstart+4, poe_tag_length));
}
break;
case PPPOE_TAG_HOST_UNIQ:
proto_tree_add_item(pppoe_tree, hf_pppoed_tag_host_uniq, tvb,
tagstart+4, poe_tag_length, FALSE);
break;
case PPPOE_TAG_AC_COOKIE:
proto_tree_add_item(pppoe_tree, hf_pppoed_tag_ac_cookie, tvb,
tagstart+4, poe_tag_length, FALSE);
break;
case PPPOE_TAG_VENDOR:
if (poe_tag_length >= 4)
{
proto_tree_add_item(pppoe_tree, hf_pppoed_tag_vendor_id, tvb,
tagstart+4, 4, FALSE);
}
if (poe_tag_length > 4)
{
proto_tree_add_item(pppoe_tree, hf_pppoed_tag_vendor_unspecified, tvb,
tagstart+4+4, poe_tag_length-4, FALSE);
}
break;
case PPPOE_TAG_CREDITS:
if (poe_tag_length == 4)
{
proto_tree_add_item(pppoe_tree, hf_pppoed_tag_credits_fcn, tvb,
tagstart+4, 2, FALSE);
proto_tree_add_item(pppoe_tree, hf_pppoed_tag_credits_bcn, tvb,
tagstart+6, 2, FALSE);
} else {
proto_tree_add_item(pppoe_tree, hf_pppoed_tag_credits, tvb,
tagstart+4, poe_tag_length, FALSE);
}
break;
case PPPOE_TAG_METRICS:
if (poe_tag_length == 10)
{
poe_rsv = tvb_get_ntohs(tvb, tagstart+4);
proto_tree_add_item(pppoe_tree, hf_pppoed_tag_mdr_units, tvb,
tagstart+4, 2, FALSE);
proto_tree_add_item(pppoe_tree, hf_pppoed_tag_cdr_units, tvb,
tagstart+4, 2, FALSE);
proto_tree_add_item(pppoe_tree, hf_pppoed_tag_metrics_r, tvb,
tagstart+4, 2, FALSE);
proto_tree_add_item(pppoe_tree, hf_pppoed_tag_metrics_rlq, tvb,
tagstart+6, 1, FALSE);
proto_tree_add_item(pppoe_tree, hf_pppoed_tag_metrics_resource, tvb,
tagstart+7, 1, FALSE);
proto_tree_add_item(pppoe_tree, hf_pppoed_tag_metrics_latency, tvb,
tagstart+8, 2, FALSE);
/* CDR */
ti = proto_tree_add_item(pppoe_tree, hf_pppoed_tag_metrics_curr_drate, tvb,
tagstart+10, 2, FALSE);
switch ((poe_rsv & PPPOE_CDR_MASK) >> 1)
{
case (PPPOE_SCALE_KBPS):
proto_item_append_text(ti, " kbps");
break;
case (PPPOE_SCALE_MBPS):
proto_item_append_text(ti, " mbps");
break;
case (PPPOE_SCALE_GBPS):
proto_item_append_text(ti, " gbps");
break;
case (PPPOE_SCALE_TBPS):
proto_item_append_text(ti, " tbps");
break;
}
/* MDR */
ti = proto_tree_add_item(pppoe_tree, hf_pppoed_tag_metrics_max_drate, tvb,
tagstart+12, 2, FALSE);
switch ((poe_rsv & PPPOE_MDR_MASK) >> 3)
{
case (PPPOE_SCALE_KBPS):
proto_item_append_text(ti, " kbps");
break;
case (PPPOE_SCALE_MBPS):
proto_item_append_text(ti, " mbps");
break;
case (PPPOE_SCALE_GBPS):
proto_item_append_text(ti, " gbps");
break;
case (PPPOE_SCALE_TBPS):
proto_item_append_text(ti, " tbps");
break;
}
} else {
proto_tree_add_item(pppoe_tree, hf_pppoed_tag_metrics, tvb,
tagstart+4, poe_tag_length, FALSE);
}
break;
case PPPOE_TAG_SEQ_NUM:
proto_tree_add_item(pppoe_tree, hf_pppoed_tag_seq_num, tvb,
tagstart+4, poe_tag_length, FALSE);
break;
case PPPOE_TAG_CRED_SCALE:
proto_tree_add_item(pppoe_tree, hf_pppoed_tag_cred_scale, tvb,
tagstart+4, poe_tag_length, FALSE);
break;
case PPPOE_TAG_RELAY_ID:
proto_tree_add_item(pppoe_tree, hf_pppoed_tag_relay_session_id, tvb,
tagstart+4, poe_tag_length, FALSE);
break;
case PPPOE_TAG_HURL:
proto_tree_add_item(pppoe_tree, hf_pppoed_tag_hurl, tvb,
tagstart+4, poe_tag_length, FALSE);
break;
case PPPOE_TAG_MOTM:
proto_tree_add_item(pppoe_tree, hf_pppoed_tag_motm, tvb,
tagstart+4, poe_tag_length, FALSE);
break;
case PPPOE_TAG_MAX_PAYLD:
proto_tree_add_item(pppoe_tree, hf_pppoed_tag_max_payload, tvb,
tagstart+4, poe_tag_length, FALSE);
break;
case PPPOE_TAG_IP_RT_ADD:
proto_tree_add_item(pppoe_tree, hf_pppoed_tag_ip_route_add, tvb,
tagstart+4, poe_tag_length, FALSE);
break;
/* These error tag values should be interpreted as a utf-8 unterminated
strings. */
case PPPOE_TAG_SVC_ERR:
proto_tree_add_item(pppoe_tree, hf_pppoed_tag_service_name_error, tvb,
tagstart+4, poe_tag_length, FALSE);
break;
case PPPOE_TAG_AC_ERR:
proto_tree_add_item(pppoe_tree, hf_pppoed_tag_ac_system_error, tvb,
tagstart+4, poe_tag_length, FALSE);
break;
case PPPOE_TAG_GENERIC_ERR:
proto_tree_add_item(pppoe_tree, hf_pppoed_tag_generic_error, tvb,
tagstart+4, poe_tag_length, FALSE);
break;
/* Get out if see end-of-list tag */
case PPPOE_TAG_EOL:
return;
default:
if (poe_tag_length > 0 )
{
/* Presumably unknown tag;
show tag value if we didn't
do it above */
if (!global_pppoe_show_tags_and_lengths)
{
proto_tree_add_item(pppoe_tree, hf_pppoed_tag, tvb, tagstart, 2, FALSE);
proto_tree_add_item(pppoe_tree, hf_pppoed_tag_length, tvb, tagstart+2, 2, FALSE);
}
proto_tree_add_item(pppoe_tree, hf_pppoed_tag_unknown_data, tvb,
tagstart+4, poe_tag_length, FALSE);
}
}
tagstart += (4 + poe_tag_length);
}
}
}
/* Discovery protocol, i.e. PPP session not yet established */
static void dissect_pppoed(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
{
guint8 pppoe_code;
guint16 reported_payload_length;
proto_tree *pppoe_tree = NULL;
proto_item *ti;
if (check_col(pinfo->cinfo, COL_PROTOCOL))
{
col_set_str(pinfo->cinfo, COL_PROTOCOL, "PPPoED");
}
if (check_col(pinfo->cinfo, COL_INFO))
{
col_clear(pinfo->cinfo, COL_INFO);
}
/* Start Decoding Here. */
pppoe_code = tvb_get_guint8(tvb, 1);
if (check_col(pinfo->cinfo, COL_INFO))
{
col_append_str(pinfo->cinfo, COL_INFO, val_to_str(pppoe_code, code_vals, "Unknown"));
}
/* Read length of payload */
reported_payload_length = tvb_get_ntohs(tvb, 4);
if (tree)
{
ti = proto_tree_add_item(tree, proto_pppoed, tvb, 0, reported_payload_length+6, FALSE);
pppoe_tree = proto_item_add_subtree(ti, ett_pppoed);
/* Dissect fixed fields */
proto_tree_add_item(pppoe_tree, hf_pppoe_version, tvb, 0, 1, FALSE);
proto_tree_add_item(pppoe_tree, hf_pppoe_type, tvb, 0, 1, FALSE);
proto_tree_add_item(pppoe_tree, hf_pppoe_code, tvb, 1, 1, FALSE);
proto_tree_add_item(pppoe_tree, hf_pppoe_session_id, tvb, 2, 2, FALSE);
proto_tree_add_item(pppoe_tree, hf_pppoe_payload_length, tvb, 4, 2, FALSE);
}
/* Now dissect any tags */
if (reported_payload_length > 0)
{
dissect_pppoe_tags(tvb, pinfo, 6, pppoe_tree, 6+reported_payload_length);
}
}
void proto_register_pppoed(void)
{
static hf_register_info hf[] =
{
/* These fields common to discovery and session protocols */
{ &hf_pppoe_version,
{ "Version", "pppoe.version", FT_UINT8, BASE_DEC,
NULL, 0xf0, "", HFILL
}
},
{ &hf_pppoe_type,
{ "Type", "pppoe.type", FT_UINT8, BASE_DEC,
NULL, 0x0f, "", HFILL
}
},
{ &hf_pppoe_code,
{ "Code", "pppoe.code", FT_UINT8, BASE_HEX,
VALS(code_vals), 0x0, "", HFILL
}
},
{ &hf_pppoe_session_id,
{ "Session ID", "pppoe.session_id", FT_UINT16, BASE_HEX,
NULL, 0x0, "", HFILL
}
},
{ &hf_pppoe_payload_length,
{ "Payload Length", "pppoe.payload_length", FT_UINT16, BASE_DEC,
NULL, 0x0, "", HFILL
}
},
/* Discovery tag fields */
{ &hf_pppoed_tags,
{ "PPPoE Tags", "pppoed.tags", FT_NONE, BASE_NONE,
NULL, 0x0, "", HFILL
}
},
{ &hf_pppoed_tag,
{ "Tag", "pppoed.tag", FT_UINT16, BASE_HEX,
VALS(tag_vals), 0x0, "", HFILL
}
},
{ &hf_pppoed_tag_length,
{ "Tag Length", "pppoed.tag_length", FT_UINT16, BASE_DEC,
NULL, 0x0, "", HFILL
}
},
{ &hf_pppoed_tag_unknown_data,
{ "Unknown Data", "pppoed.tag.unknown_data", FT_BYTES, BASE_NONE,
NULL, 0x0, "", HFILL
}
},
{ &hf_pppoed_tag_service_name,
{ "Service-Name", "pppoed.tags.service_name", FT_STRING, BASE_NONE,
NULL, 0x0, "", HFILL
}
},
{ &hf_pppoed_tag_ac_name,
{ "AC-Name", "pppoed.tags.ac_name", FT_STRING, BASE_NONE,
NULL, 0x0, "", HFILL
}
},
{ &hf_pppoed_tag_host_uniq,
{ "Host-Uniq", "pppoed.tags.host_uniq", FT_BYTES, BASE_NONE,
NULL, 0x0, "", HFILL
}
},
{ &hf_pppoed_tag_ac_cookie,
{ "AC-Cookie", "pppoed.tags.ac_cookie", FT_BYTES, BASE_NONE,
NULL, 0x0, "", HFILL
}
},
{ &hf_pppoed_tag_vendor_id,
{ "Vendor id", "pppoed.tags.vendor_id", FT_UINT32, BASE_HEX,
NULL, 0x0, "", HFILL
}
},
{ &hf_pppoed_tag_vendor_unspecified,
{ "Vendor unspecified", "pppoed.tags.vendor_unspecified", FT_BYTES, BASE_HEX,
NULL, 0x0, "", HFILL
}
},
{ &hf_pppoed_tag_credits,
{ "Credits", "pppoed.tags.credits", FT_BYTES, BASE_HEX,
NULL, 0x0, "", HFILL
}
},
{ &hf_pppoed_tag_credits_fcn,
{ "FCN", "pppoed.tags.credits.fcn", FT_UINT16, BASE_DEC,
NULL, 0x0, "", HFILL
}
},
{ &hf_pppoed_tag_credits_bcn,
{ "BCN", "pppoed.tags.credits.bcn", FT_UINT16, BASE_DEC,
NULL, 0x0, "", HFILL
}
},
{ &hf_pppoed_tag_metrics,
{ "Metrics", "pppoed.tags.metrics", FT_BYTES, BASE_HEX,
NULL, 0x0, "", HFILL
}
},
{ &hf_pppoed_tag_metrics_r,
{ "Receive Only", "pppoed.tags.metrics.r", FT_BOOLEAN, 16,
NULL, PPPOE_RCV_ONLY_MASK, "", HFILL
}
},
{ &hf_pppoed_tag_mdr_units,
{ "MDR Units", "pppoed.tags.metrics.mdr_units", FT_UINT16, BASE_HEX,
VALS(datarate_scale_vals), PPPOE_MDR_MASK, "", HFILL
}
},
{ &hf_pppoed_tag_cdr_units,
{ "CDR Units", "pppoed.tags.metrics.cdr_units", FT_UINT16, BASE_HEX,
VALS(datarate_scale_vals), PPPOE_CDR_MASK, "", HFILL
}
},
{ &hf_pppoed_tag_metrics_rlq,
{ "Relative Link Quality", "pppoed.tags.metrics.rlq", FT_UINT8, BASE_DEC,
NULL, 0x0, "", HFILL
}
},
{ &hf_pppoed_tag_metrics_resource,
{ "Resource", "pppoed.tags.metrics.resource", FT_UINT8, BASE_DEC,
NULL, 0x0, "", HFILL
}
},
{ &hf_pppoed_tag_metrics_latency,
{ "Latency", "pppoed.tags.metrics.latency", FT_UINT16, BASE_DEC,
NULL, 0x0, "", HFILL
}
},
{ &hf_pppoed_tag_metrics_curr_drate,
{ "Curr. datarate", "pppoed.tags.metrics.curr_drate", FT_UINT16, BASE_DEC,
NULL, 0x0, "", HFILL
}
},
{ &hf_pppoed_tag_metrics_max_drate,
{ "Max. datarate", "pppoed.tags.metrics.max_drate", FT_UINT16, BASE_DEC,
NULL, 0x0, "", HFILL
}
},
{ &hf_pppoed_tag_seq_num,
{ "Sequence Number", "pppoed.tags.seq_num", FT_UINT16, BASE_HEX,
NULL, 0x0, "", HFILL
}
},
{ &hf_pppoed_tag_cred_scale,
{ "Credit Scale Factor", "pppoed.tags.credit_scale", FT_UINT16, BASE_DEC,
NULL, 0x0, "", HFILL
}
},
{ &hf_pppoed_tag_relay_session_id,
{ "Relay-Session-Id", "pppoed.tags.relay_session_id", FT_BYTES, BASE_NONE,
NULL, 0x0, "", HFILL
}
},
{ &hf_pppoed_tag_hurl,
{ "HURL", "pppoed.tags.hurl", FT_BYTES, BASE_HEX,
NULL, 0x0, "", HFILL
}
},
{ &hf_pppoed_tag_motm,
{ "MOTM", "pppoed.tags.motm", FT_BYTES, BASE_HEX,
NULL, 0x0, "", HFILL
}
},
{ &hf_pppoed_tag_max_payload,
{ "PPP Max Palyload", "pppoed.tags.max_payload", FT_BYTES, BASE_HEX,
NULL, 0x0, "", HFILL
}
},
{ &hf_pppoed_tag_ip_route_add,
{ "IP Route Add", "pppoed.tags.ip_route_add", FT_BYTES, BASE_HEX,
NULL, 0x0, "", HFILL
}
},
{ &hf_pppoed_tag_service_name_error,
{ "Service-Name-Error", "pppoed.tags.service_name_error", FT_STRING, BASE_NONE,
NULL, 0x0, "", HFILL
}
},
{ &hf_pppoed_tag_ac_system_error,
{ "AC-System-Error", "pppoed.tags.ac_system_error", FT_STRING, BASE_NONE,
NULL, 0x0, "", HFILL
}
},
{ &hf_pppoed_tag_generic_error,
{ "Generic-Error", "pppoed.tags.generic_error", FT_STRING, BASE_NONE,
NULL, 0x0, "", HFILL
}
},
};
static gint *ett[] = {
&ett_pppoed,
&ett_pppoed_tags,
};
module_t *pppoed_module;
/* Register protocol and fields */
proto_pppoed = proto_register_protocol("PPP-over-Ethernet Discovery",
"PPPoED", "pppoed");
proto_register_subtree_array(ett, array_length(ett));
proto_register_field_array(proto_pppoed, hf, array_length(hf));
/* Preference setting */
pppoed_module = prefs_register_protocol(proto_pppoed, NULL);
prefs_register_bool_preference(pppoed_module, "show_tags_and_lengths",
"Show tag values and lengths",
"Show values of tags and lengths of data fields",
&global_pppoe_show_tags_and_lengths);
}
void proto_reg_handoff_pppoed(void)
{
dissector_handle_t pppoed_handle;
pppoed_handle = create_dissector_handle(dissect_pppoed, proto_pppoed);
dissector_add("ethertype", ETHERTYPE_PPPOED, pppoed_handle);
}
/* Session protocol, i.e. PPP session established */
static void dissect_pppoes(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
{
guint8 pppoe_code;
guint16 pppoe_session_id;
guint16 reported_payload_length;
gint actual_payload_length;
gint length, reported_length;
proto_tree *pppoe_tree;
proto_item *ti = NULL;
tvbuff_t *next_tvb;
if (check_col(pinfo->cinfo, COL_PROTOCOL))
{
col_set_str(pinfo->cinfo,COL_PROTOCOL, "PPPoES");
}
if (check_col(pinfo->cinfo,COL_INFO))
{
col_clear(pinfo->cinfo,COL_INFO);
}
/* Start Decoding Here. */
pppoe_code = tvb_get_guint8(tvb, 1);
if (check_col(pinfo->cinfo,COL_INFO))
{
col_add_str(pinfo->cinfo, COL_INFO,
val_to_str(pppoe_code, code_vals, "Unknown"));
}
pppoe_session_id = tvb_get_ntohs(tvb, 2);
reported_payload_length = tvb_get_ntohs(tvb, 4);
actual_payload_length = tvb_reported_length_remaining(tvb, 6);
if (tree)
{
ti = proto_tree_add_item(tree, proto_pppoes, tvb, 0, 6, FALSE);
pppoe_tree = proto_item_add_subtree(ti, ett_pppoed);
proto_tree_add_item(pppoe_tree, hf_pppoe_version, tvb, 0, 1, FALSE);
proto_tree_add_item(pppoe_tree, hf_pppoe_type, tvb, 0, 1, FALSE);
proto_tree_add_item(pppoe_tree, hf_pppoe_code, tvb, 1, 1, FALSE);
proto_tree_add_item(pppoe_tree, hf_pppoe_session_id, tvb, 2, 2, FALSE);
ti = proto_tree_add_item(pppoe_tree, hf_pppoe_payload_length, tvb, 4, 2, FALSE);
}
/*
* The only reason why the payload length from the header
* should differ from the remaining data in the packet
* would be if the total packet length, including Ethernet
* CRC, were < 64 bytes, so that padding was required.
*
* That means that you have 14 bytes of Ethernet header,
* 4 bytes of FCS, and fewer than 46 bytes of PPPoE packet.
*
* If that's not the case, we report a difference between
* the payload length in the packet, and the amount of
* data following the PPPoE header, as an error.
*/
if (tvb_reported_length(tvb) > 46 &&
reported_payload_length != actual_payload_length) {
proto_item_append_text(ti, " [incorrect, should be %u]",
actual_payload_length);
expert_add_info_format(pinfo, ti, PI_MALFORMED,
PI_WARN, "Possible bad payload length %u != %u",
reported_payload_length, actual_payload_length);
}
/*
* Construct a tvbuff containing the PPP packet.
*/
length = tvb_length_remaining(tvb, 6);
reported_length = tvb_reported_length_remaining(tvb, 6);
DISSECTOR_ASSERT(length >= 0);
DISSECTOR_ASSERT(reported_length >= 0);
if (length > reported_length)
length = reported_length;
if ((guint)length > reported_payload_length)
length = reported_payload_length;
if ((guint)reported_length > reported_payload_length)
reported_length = reported_payload_length;
next_tvb = tvb_new_subset(tvb,6,length,reported_length);
call_dissector(ppp_handle,next_tvb,pinfo,tree);
}
void proto_register_pppoes(void)
{
/* Register protocol */
proto_pppoes = proto_register_protocol("PPP-over-Ethernet Session", "PPPoES", "pppoes");
}
void proto_reg_handoff_pppoes(void)
{
dissector_handle_t pppoes_handle =
create_dissector_handle(dissect_pppoes, proto_pppoes);
dissector_add("ethertype", ETHERTYPE_PPPOES, pppoes_handle);
/* Get a handle for the PPP dissector */
ppp_handle = find_dissector("ppp");
}
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