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Add support for dissecting the 802.1t System ID Extensions 

within the Bridge Identifiers.

(Inspired by http://packetlife.net/blog/2008/sep/26/vlan-challenge/)


svn path=/trunk/; revision=26348
This commit is contained in:
Sake Blok 2008-10-03 22:11:13 +00:00
parent acd4e734c9
commit 8b82ba219b
1 changed files with 262 additions and 50 deletions
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312
epan/dissectors/packet-bpdu.c
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@ -37,6 +37,7 @@
#include <epan/chdlctypes.h>
#include <epan/etypes.h>
#include <epan/addr_resolv.h>
#include <epan/prefs.h>
/* Offsets of fields within a BPDU */
@ -115,8 +116,12 @@ static int hf_bpdu_flags_learning = -1;
static int hf_bpdu_flags_port_role = -1;
static int hf_bpdu_flags_proposal = -1;
static int hf_bpdu_flags_tc = -1;
static int hf_bpdu_root_prio = -1;
static int hf_bpdu_root_sys_id_ext = -1;
static int hf_bpdu_root_mac = -1;
static int hf_bpdu_root_cost = -1;
static int hf_bpdu_bridge_prio = -1;
static int hf_bpdu_bridge_sys_id_ext = -1;
static int hf_bpdu_bridge_mac = -1;
static int hf_bpdu_port_id = -1;
static int hf_bpdu_msg_age = -1;
@ -130,7 +135,9 @@ static int hf_bpdu_mst_config_name = -1;
static int hf_bpdu_mst_config_revision_level = -1;
static int hf_bpdu_mst_config_digest = -1;
static int hf_bpdu_cist_internal_root_path_cost = -1;
static int hf_bpdu_cist_bridge_identifier_mac = -1;
static int hf_bpdu_cist_bridge_prio = -1;
static int hf_bpdu_cist_bridge_sys_id_ext = -1;
static int hf_bpdu_cist_bridge_mac = -1;
static int hf_bpdu_cist_remaining_hops = -1;
static int hf_bpdu_msti_flags = -1;
static int hf_bpdu_msti_regional_root_mac = -1;
@ -142,8 +149,13 @@ static int hf_bpdu_msti_remaining_hops = -1;
static gint ett_bpdu = -1;
static gint ett_bpdu_flags = -1;
static gint ett_root_id = -1;
static gint ett_bridge_id = -1;
static gint ett_mstp = -1;
static gint ett_msti = -1;
static gint ett_cist_bridge_id = -1;
static gboolean bpdu_use_system_id_extensions = TRUE;
static dissector_handle_t gvrp_handle;
static dissector_handle_t gmrp_handle;
@ -204,10 +216,12 @@ dissect_bpdu(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
guint8 bpdu_type;
guint8 flags;
guint16 root_identifier_bridge_priority;
guint16 root_identifier_system_id_extension = 0;
const guint8 *root_identifier_mac;
gchar *root_identifier_mac_str;
guint32 root_path_cost;
guint16 bridge_identifier_bridge_priority;
guint16 bridge_identifier_system_id_extension = 0;
const guint8 *bridge_identifier_mac;
gchar *bridge_identifier_mac_str;
guint16 port_identifier;
@ -219,6 +233,7 @@ dissect_bpdu(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
guint16 version_3_length;
guint8 config_format_selector;
guint16 cist_bridge_identifier_bridge_priority;
guint16 cist_bridge_identifier_system_id_extension = 0;
const guint8 *cist_bridge_identifier_mac;
gchar *cist_bridge_identifier_mac_str;
guint16 msti_mstid;
@ -236,6 +251,12 @@ dissect_bpdu(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
proto_item *mstp_item, *msti_item;
proto_tree *flags_tree;
proto_item *flags_item;
proto_tree *root_id_tree;
proto_item *root_id_item;
proto_tree *bridge_id_tree;
proto_item *bridge_id_item;
proto_tree *cist_bridge_id_tree;
proto_item *cist_bridge_id_item;
proto_item *hidden_item;
const char *sep;
@ -306,6 +327,10 @@ dissect_bpdu(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
case BPDU_TYPE_RST:
flags = tvb_get_guint8(tvb, BPDU_FLAGS);
root_identifier_bridge_priority = tvb_get_ntohs(tvb,BPDU_ROOT_IDENTIFIER);
if (bpdu_use_system_id_extensions ) {
root_identifier_system_id_extension = root_identifier_bridge_priority & 0x0fff;
root_identifier_bridge_priority &= 0xf000;
}
root_identifier_mac = tvb_get_ptr(tvb, BPDU_ROOT_IDENTIFIER + 2, 6);
root_identifier_mac_str = ether_to_str(root_identifier_mac);
root_path_cost = tvb_get_ntohl(tvb, BPDU_ROOT_PATH_COST);
@ -327,11 +352,21 @@ dissect_bpdu(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
switch (bpdu_type) {
case BPDU_TYPE_CONF:
col_add_fstr(pinfo->cinfo, COL_INFO,
"Conf. %sRoot = %d/%s Cost = %d Port = 0x%04x",
flags & 0x1 ? "TC + " : "",
root_identifier_bridge_priority, root_identifier_mac_str,
root_path_cost, port_identifier);
if (bpdu_use_system_id_extensions ) {
col_add_fstr(pinfo->cinfo, COL_INFO,
"Conf. %sRoot = %d/%d/%s Cost = %d Port = 0x%04x",
flags & 0x1 ? "TC + " : "",
root_identifier_bridge_priority,
root_identifier_system_id_extension,
root_identifier_mac_str,
root_path_cost, port_identifier);
} else {
col_add_fstr(pinfo->cinfo, COL_INFO,
"Conf. %sRoot = %d/%s Cost = %d Port = 0x%04x",
flags & 0x1 ? "TC + " : "",
root_identifier_bridge_priority, root_identifier_mac_str,
root_path_cost, port_identifier);
}
break;
case BPDU_TYPE_TOPOLOGY_CHANGE:
@ -339,12 +374,23 @@ dissect_bpdu(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
break;
case BPDU_TYPE_RST:
col_add_fstr(pinfo->cinfo, COL_INFO,
"%cST. %sRoot = %d/%s Cost = %d Port = 0x%04x",
protocol_version_identifier == 3 ? 'M':'R',
flags & 0x1 ? "TC + " : "",
root_identifier_bridge_priority, root_identifier_mac_str,
root_path_cost, port_identifier);
if (bpdu_use_system_id_extensions ) {
col_add_fstr(pinfo->cinfo, COL_INFO,
"%cST. %sRoot = %d/%d/%s Cost = %d Port = 0x%04x",
protocol_version_identifier == 3 ? 'M':'R',
flags & 0x1 ? "TC + " : "",
root_identifier_bridge_priority,
root_identifier_system_id_extension,
root_identifier_mac_str,
root_path_cost, port_identifier);
} else {
col_add_fstr(pinfo->cinfo, COL_INFO,
"%cST. %sRoot = %d/%s Cost = %d Port = 0x%04x",
protocol_version_identifier == 3 ? 'M':'R',
flags & 0x1 ? "TC + " : "",
root_identifier_bridge_priority, root_identifier_mac_str,
root_path_cost, port_identifier);
}
break;
default:
@ -394,6 +440,10 @@ dissect_bpdu(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
}
bridge_identifier_bridge_priority = tvb_get_ntohs(tvb, BPDU_BRIDGE_IDENTIFIER);
if (bpdu_use_system_id_extensions ) {
bridge_identifier_system_id_extension = bridge_identifier_bridge_priority & 0x0fff;
bridge_identifier_bridge_priority &= 0xf000;
}
bridge_identifier_mac = tvb_get_ptr(tvb, BPDU_BRIDGE_IDENTIFIER + 2, 6);
bridge_identifier_mac_str = ether_to_str(bridge_identifier_mac);
@ -443,24 +493,85 @@ dissect_bpdu(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
proto_item_append_text(flags_item, ")");
}
hidden_item = proto_tree_add_ether(bpdu_tree, hf_bpdu_root_mac, tvb,
BPDU_ROOT_IDENTIFIER + 2, 6,
root_identifier_mac);
PROTO_ITEM_SET_HIDDEN(hidden_item);
proto_tree_add_text(bpdu_tree, tvb, BPDU_ROOT_IDENTIFIER, 8,
"Root Identifier: %d / %s",
root_identifier_bridge_priority,
root_identifier_mac_str);
/* add Identifier with format based on preference value
* bpdu_use_system_id_extensions
* */
if (bpdu_use_system_id_extensions) {
root_id_item = proto_tree_add_text(bpdu_tree, tvb,
BPDU_ROOT_IDENTIFIER, 8,
"Root Identifier: %d / %d / %s",
root_identifier_bridge_priority,
root_identifier_system_id_extension,
root_identifier_mac_str);
root_id_tree = proto_item_add_subtree(root_id_item, ett_root_id);
proto_tree_add_uint(root_id_tree, hf_bpdu_root_prio, tvb,
BPDU_ROOT_IDENTIFIER , 1,
root_identifier_bridge_priority);
proto_tree_add_uint(root_id_tree, hf_bpdu_root_sys_id_ext, tvb,
BPDU_ROOT_IDENTIFIER , 2,
root_identifier_system_id_extension);
proto_tree_add_ether_format_value(root_id_tree, hf_bpdu_root_mac,
tvb, BPDU_ROOT_IDENTIFIER + 2, 6,
root_identifier_mac,
"%s", root_identifier_mac_str);
} else {
root_id_item = proto_tree_add_text(bpdu_tree, tvb,
BPDU_ROOT_IDENTIFIER, 8,
"Root Identifier: %d / %s",
root_identifier_bridge_priority,
root_identifier_mac_str);
root_id_tree = proto_item_add_subtree(root_id_item, ett_root_id);
proto_tree_add_uint(root_id_tree, hf_bpdu_root_prio, tvb,
BPDU_ROOT_IDENTIFIER , 2,
root_identifier_bridge_priority);
proto_tree_add_ether_format_value(root_id_tree, hf_bpdu_root_mac,
tvb, BPDU_ROOT_IDENTIFIER + 2, 6,
root_identifier_mac,
"%s", root_identifier_mac_str);
}
/* end of Identifier formatting */
proto_tree_add_uint(bpdu_tree, hf_bpdu_root_cost, tvb,
BPDU_ROOT_PATH_COST, 4, root_path_cost);
proto_tree_add_text(bpdu_tree, tvb, BPDU_BRIDGE_IDENTIFIER, 8,
"Bridge Identifier: %d / %s",
bridge_identifier_bridge_priority,
bridge_identifier_mac_str);
hidden_item= proto_tree_add_ether(bpdu_tree, hf_bpdu_bridge_mac, tvb,
BPDU_BRIDGE_IDENTIFIER + 2, 6,
bridge_identifier_mac);
PROTO_ITEM_SET_HIDDEN(hidden_item);
/* add Identifier with format based on preference value
* bpdu_use_system_id_extensions
* */
if (bpdu_use_system_id_extensions) {
bridge_id_item = proto_tree_add_text(bpdu_tree, tvb,
BPDU_BRIDGE_IDENTIFIER, 8,
"Bridge Identifier: %d / %d / %s",
bridge_identifier_bridge_priority,
bridge_identifier_system_id_extension,
bridge_identifier_mac_str);
bridge_id_tree = proto_item_add_subtree(bridge_id_item, ett_bridge_id);
proto_tree_add_uint(bridge_id_tree, hf_bpdu_bridge_prio, tvb,
BPDU_BRIDGE_IDENTIFIER , 1,
bridge_identifier_bridge_priority);
proto_tree_add_uint(bridge_id_tree, hf_bpdu_bridge_sys_id_ext, tvb,
BPDU_BRIDGE_IDENTIFIER , 2,
bridge_identifier_system_id_extension);
proto_tree_add_ether_format_value(bridge_id_tree, hf_bpdu_bridge_mac,
tvb, BPDU_BRIDGE_IDENTIFIER + 2, 6,
bridge_identifier_mac,
"%s", bridge_identifier_mac_str);
} else {
bridge_id_item = proto_tree_add_text(bpdu_tree, tvb,
BPDU_BRIDGE_IDENTIFIER, 8,
"Bridge Identifier: %d / %s",
bridge_identifier_bridge_priority,
bridge_identifier_mac_str);
bridge_id_tree = proto_item_add_subtree(bridge_id_item, ett_bridge_id);
proto_tree_add_uint(bridge_id_tree, hf_bpdu_bridge_prio, tvb,
BPDU_BRIDGE_IDENTIFIER , 2,
bridge_identifier_bridge_priority);
proto_tree_add_ether_format_value(bridge_id_tree, hf_bpdu_bridge_mac,
tvb, BPDU_BRIDGE_IDENTIFIER + 2, 6,
bridge_identifier_mac,
"%s", bridge_identifier_mac_str);
}
/* end of Identifier formatting */
proto_tree_add_uint(bpdu_tree, hf_bpdu_port_id, tvb,
BPDU_PORT_IDENTIFIER, 2, port_identifier);
message_age = tvb_get_ntohs(tvb, BPDU_MESSAGE_AGE) / 256.0;
@ -577,28 +688,95 @@ dissect_bpdu(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
cist_bridge_identifier_bridge_priority = tvb_get_ntohs(tvb,BPDU_CIST_BRIDGE_IDENTIFIER);
cist_bridge_identifier_mac = tvb_get_ptr(tvb, BPDU_CIST_BRIDGE_IDENTIFIER + 2, 6);
cist_bridge_identifier_mac_str = ether_to_str(cist_bridge_identifier_mac);
proto_tree_add_text(mstp_tree, tvb, BPDU_CIST_BRIDGE_IDENTIFIER, 8,
"CIST Bridge Identifier: %d / %s",
cist_bridge_identifier_bridge_priority,
cist_bridge_identifier_mac_str);
hidden_item = proto_tree_add_ether(mstp_tree, hf_bpdu_cist_bridge_identifier_mac, tvb,
BPDU_CIST_BRIDGE_IDENTIFIER + 2, 6,
cist_bridge_identifier_mac);
PROTO_ITEM_SET_HIDDEN(hidden_item);
/* add Identifier with format based on preference value
* bpdu_use_system_id_extensions
* */
if (bpdu_use_system_id_extensions ) {
cist_bridge_identifier_system_id_extension = cist_bridge_identifier_bridge_priority & 0x0fff;
cist_bridge_identifier_bridge_priority &= 0xf000;
cist_bridge_id_item = proto_tree_add_text(mstp_tree, tvb,
BPDU_CIST_BRIDGE_IDENTIFIER, 8,
"CIST Bridge Identifier: %d / %d / %s",
cist_bridge_identifier_bridge_priority,
cist_bridge_identifier_system_id_extension,
cist_bridge_identifier_mac_str);
cist_bridge_id_tree = proto_item_add_subtree(cist_bridge_id_item, ett_cist_bridge_id);
proto_tree_add_uint(cist_bridge_id_tree, hf_bpdu_cist_bridge_prio, tvb,
BPDU_CIST_BRIDGE_IDENTIFIER , 1,
cist_bridge_identifier_bridge_priority);
proto_tree_add_uint(cist_bridge_id_tree, hf_bpdu_cist_bridge_sys_id_ext, tvb,
BPDU_CIST_BRIDGE_IDENTIFIER , 2,
cist_bridge_identifier_system_id_extension);
proto_tree_add_ether_format_value(cist_bridge_id_tree, hf_bpdu_cist_bridge_mac,
tvb, BPDU_CIST_BRIDGE_IDENTIFIER + 2, 6,
cist_bridge_identifier_mac,
"%s", cist_bridge_identifier_mac_str);
} else {
cist_bridge_id_item = proto_tree_add_text(mstp_tree, tvb,
BPDU_CIST_BRIDGE_IDENTIFIER, 8,
"CIST Bridge Identifier: %d / %s",
cist_bridge_identifier_bridge_priority,
cist_bridge_identifier_mac_str);
cist_bridge_id_tree = proto_item_add_subtree(cist_bridge_id_item, ett_cist_bridge_id);
proto_tree_add_uint(cist_bridge_id_tree, hf_bpdu_cist_bridge_prio, tvb,
BPDU_CIST_BRIDGE_IDENTIFIER , 2,
cist_bridge_identifier_bridge_priority);
proto_tree_add_ether_format_value(cist_bridge_id_tree, hf_bpdu_cist_bridge_mac,
tvb, BPDU_CIST_BRIDGE_IDENTIFIER + 2, 6,
cist_bridge_identifier_mac,
"%s", cist_bridge_identifier_mac_str);
}
/* end of Identifier formatting */
break;
case MSTI_FORMAT_ALTERNATIVE:
cist_bridge_identifier_bridge_priority = tvb_get_ntohs(tvb,ALT_BPDU_CIST_BRIDGE_IDENTIFIER);
cist_bridge_identifier_mac = tvb_get_ptr(tvb, ALT_BPDU_CIST_BRIDGE_IDENTIFIER + 2, 6);
cist_bridge_identifier_mac_str = ether_to_str(cist_bridge_identifier_mac);
proto_tree_add_text(mstp_tree, tvb, ALT_BPDU_CIST_BRIDGE_IDENTIFIER, 8,
"CIST Bridge Identifier: %d / %s",
cist_bridge_identifier_bridge_priority,
cist_bridge_identifier_mac_str);
hidden_item = proto_tree_add_ether(mstp_tree, hf_bpdu_cist_bridge_identifier_mac, tvb,
ALT_BPDU_CIST_BRIDGE_IDENTIFIER + 2, 6,
cist_bridge_identifier_mac);
PROTO_ITEM_SET_HIDDEN(hidden_item);
/* add Identifier with format based on preference value
* bpdu_use_system_id_extensions
* */
if (bpdu_use_system_id_extensions ) {
cist_bridge_identifier_system_id_extension = cist_bridge_identifier_bridge_priority & 0x0fff;
cist_bridge_identifier_bridge_priority &= 0xf000;
cist_bridge_id_item = proto_tree_add_text(mstp_tree, tvb,
ALT_BPDU_CIST_BRIDGE_IDENTIFIER, 8,
"CIST Bridge Identifier: %d / %d / %s",
cist_bridge_identifier_bridge_priority,
cist_bridge_identifier_system_id_extension,
cist_bridge_identifier_mac_str);
cist_bridge_id_tree = proto_item_add_subtree(cist_bridge_id_item, ett_cist_bridge_id);
proto_tree_add_uint(cist_bridge_id_tree, hf_bpdu_cist_bridge_prio, tvb,
ALT_BPDU_CIST_BRIDGE_IDENTIFIER , 1,
cist_bridge_identifier_bridge_priority);
proto_tree_add_uint(cist_bridge_id_tree, hf_bpdu_cist_bridge_sys_id_ext, tvb,
ALT_BPDU_CIST_BRIDGE_IDENTIFIER , 2,
cist_bridge_identifier_system_id_extension);
proto_tree_add_ether_format_value(cist_bridge_id_tree, hf_bpdu_cist_bridge_mac,
tvb, ALT_BPDU_CIST_BRIDGE_IDENTIFIER + 2, 6,
cist_bridge_identifier_mac,
"%s", cist_bridge_identifier_mac_str);
} else {
cist_bridge_id_item = proto_tree_add_text(mstp_tree, tvb,
ALT_BPDU_CIST_BRIDGE_IDENTIFIER, 8,
"CIST Bridge Identifier: %d / %s",
cist_bridge_identifier_bridge_priority,
cist_bridge_identifier_mac_str);
cist_bridge_id_tree = proto_item_add_subtree(cist_bridge_id_item, ett_cist_bridge_id);
proto_tree_add_uint(cist_bridge_id_tree, hf_bpdu_cist_bridge_prio, tvb,
ALT_BPDU_CIST_BRIDGE_IDENTIFIER , 2,
cist_bridge_identifier_bridge_priority);
proto_tree_add_ether_format_value(cist_bridge_id_tree, hf_bpdu_cist_bridge_mac,
tvb, ALT_BPDU_CIST_BRIDGE_IDENTIFIER + 2, 6,
cist_bridge_identifier_mac,
"%s", cist_bridge_identifier_mac_str);
}
/* end of Identifier formatting */
proto_tree_add_item(mstp_tree, hf_bpdu_cist_internal_root_path_cost, tvb,
ALT_BPDU_CIST_INTERNAL_ROOT_PATH_COST, 4, FALSE);
@ -854,16 +1032,32 @@ proto_register_bpdu(void)
{ "Topology Change", "stp.flags.tc",
FT_BOOLEAN, 8, TFS(&yesno), BPDU_FLAGS_TC,
"", HFILL }},
{ &hf_bpdu_root_prio,
{ "Root Bridge Priority", "stp.root.prio",
FT_UINT16, BASE_DEC, NULL, 0x0,
"", HFILL }},
{ &hf_bpdu_root_sys_id_ext,
{ "Root Bridge System ID Extension", "stp.root.ext",
FT_UINT16, BASE_DEC, NULL, 0x0,
"", HFILL }},
{ &hf_bpdu_root_mac,
{ "Root Identifier", "stp.root.hw",
{ "Root Bridge System ID", "stp.root.hw",
FT_ETHER, BASE_NONE, NULL, 0x0,
"", HFILL }},
{ &hf_bpdu_root_cost,
{ "Root Path Cost", "stp.root.cost",
FT_UINT32, BASE_DEC, NULL, 0x0,
"", HFILL }},
{ &hf_bpdu_bridge_prio,
{ "Bridge Priority", "stp.bridge.prio",
FT_UINT16, BASE_DEC, NULL, 0x0,
"", HFILL }},
{ &hf_bpdu_bridge_sys_id_ext,
{ "Bridge System ID Extension", "stp.bridge.ext",
FT_UINT16, BASE_DEC, NULL, 0x0,
"", HFILL }},
{ &hf_bpdu_bridge_mac,
{ "Bridge Identifier", "stp.bridge.hw",
{ "Bridge System ID", "stp.bridge.hw",
FT_ETHER, BASE_NONE, NULL, 0x0,
"", HFILL }},
{ &hf_bpdu_port_id,
@ -914,9 +1108,17 @@ proto_register_bpdu(void)
{ "CIST Internal Root Path Cost", "mstp.cist_internal_root_path_cost",
FT_UINT32, BASE_DEC, NULL, 0x0,
"", HFILL }},
{ &hf_bpdu_cist_bridge_identifier_mac,
{ "CIST Bridge Identifier", "mstp.cist_bridge.hw",
FT_ETHER, BASE_DEC, NULL, 0x0,
{ &hf_bpdu_cist_bridge_prio,
{ "CIST Bridge Priority", "mstp.cist_bridge.prio",
FT_UINT16, BASE_DEC, NULL, 0x0,
"", HFILL }},
{ &hf_bpdu_cist_bridge_sys_id_ext,
{ "CIST Bridge Identifier System ID Extension", "mstp.cist_bridge.ext",
FT_UINT16, BASE_DEC, NULL, 0x0,
"", HFILL }},
{ &hf_bpdu_cist_bridge_mac,
{ "CIST Bridge Identifier System ID", "mstp.cist_bridge.hw",
FT_ETHER, BASE_NONE, NULL, 0x0,
"", HFILL }},
{ &hf_bpdu_cist_remaining_hops,
{ "CIST Remaining hops", "mstp.cist_remaining_hops",
@ -955,15 +1157,25 @@ proto_register_bpdu(void)
static gint *ett[] = {
&ett_bpdu,
&ett_bpdu_flags,
&ett_root_id,
&ett_bridge_id,
&ett_mstp,
&ett_msti
&ett_msti,
&ett_cist_bridge_id
};
module_t *bpdu_module;
proto_bpdu = proto_register_protocol("Spanning Tree Protocol", "STP", "stp");
proto_register_field_array(proto_bpdu, hf, array_length(hf));
proto_register_subtree_array(ett, array_length(ett));
register_dissector("bpdu", dissect_bpdu, proto_bpdu);
bpdu_module = prefs_register_protocol(proto_bpdu, NULL);
prefs_register_bool_preference(bpdu_module, "use_system_id_extension",
"Use 801.1t System ID Extensions",
"Whether the BPDU dissector should use 801.1t System ID Extensions when dissecting the Bridge Identifier",
&bpdu_use_system_id_extensions);
}
void