1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
|
/* packet-loop.c
* Routines for Ethernet loopback/Configuration Test Protocol dissection
*
* See
*
* http://stuff.mit.edu/people/jhawk/ctp.html
*
* 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 <glib.h>
#include <epan/packet.h>
#include <epan/etypes.h>
void proto_register_loop(void);
void proto_reg_handoff_loop(void);
static int proto_loop = -1;
static int hf_loop_skipcount = -1;
static int hf_loop_function = -1;
static int hf_loop_relevant_function = -1;
static int hf_loop_receipt_number = -1;
static int hf_loop_forwarding_address = -1;
static gint ett_loop = -1;
static dissector_handle_t data_handle;
#define FUNC_REPLY 1
#define FUNC_FORWARD_DATA 2
static const value_string function_vals[] = {
{ FUNC_REPLY, "Reply" },
{ FUNC_FORWARD_DATA, "Forward Data" },
{ 0, NULL }
};
static void
dissect_loop(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
{
proto_tree *loop_tree = NULL;
proto_item *ti;
guint16 function;
int offset = 0;
int skip_offset;
gboolean set_info = TRUE;
gboolean more_function;
tvbuff_t *next_tvb;
col_set_str(pinfo->cinfo, COL_PROTOCOL, "LOOP");
col_clear(pinfo->cinfo, COL_INFO);
if (tree) {
ti = proto_tree_add_item(tree, proto_loop, tvb, offset, -1, ENC_NA);
loop_tree = proto_item_add_subtree(ti, ett_loop);
proto_tree_add_item(loop_tree, hf_loop_skipcount, tvb, offset, 2, ENC_LITTLE_ENDIAN);
}
skip_offset = 2 + tvb_get_letohs(tvb, offset);
offset += 2;
do {
function = tvb_get_letohs(tvb, offset);
if (offset == skip_offset) {
col_add_str(pinfo->cinfo, COL_INFO,
val_to_str(function, function_vals, "Unknown function (%u)"));
proto_tree_add_uint(loop_tree, hf_loop_relevant_function, tvb, offset, 2, function);
set_info = FALSE;
}
proto_tree_add_uint(loop_tree, hf_loop_function, tvb, offset, 2, function);
offset += 2;
switch (function) {
case FUNC_REPLY:
proto_tree_add_item(loop_tree, hf_loop_receipt_number, tvb, offset, 2,
ENC_LITTLE_ENDIAN);
offset += 2;
more_function = FALSE;
break;
case FUNC_FORWARD_DATA:
proto_tree_add_item(loop_tree, hf_loop_forwarding_address, tvb, offset,
6, ENC_NA);
offset += 6;
more_function = TRUE;
break;
default:
more_function = FALSE;
break;
}
} while (more_function);
if (set_info) {
col_set_str(pinfo->cinfo, COL_INFO, "No valid function found");
}
if (tvb_length_remaining(tvb, offset) > 0)
{
next_tvb = tvb_new_subset_remaining(tvb, offset);
call_dissector(data_handle, next_tvb, pinfo, tree);
}
}
void
proto_register_loop(void)
{
static hf_register_info hf[] = {
{ &hf_loop_skipcount,
{ "skipCount", "loop.skipcount",
FT_UINT16, BASE_DEC, NULL, 0x0,
NULL, HFILL }},
{ &hf_loop_function,
{ "Function", "loop.function",
FT_UINT16, BASE_DEC, VALS(function_vals), 0x0,
NULL, HFILL }},
{ &hf_loop_relevant_function,
{ "Relevant function", "loop.relevant_function",
FT_UINT16, BASE_DEC, VALS(function_vals), 0x0,
NULL, HFILL }},
{ &hf_loop_receipt_number,
{ "Receipt number", "loop.receipt_number",
FT_UINT16, BASE_DEC, NULL, 0x0,
NULL, HFILL }},
{ &hf_loop_forwarding_address,
{ "Forwarding address", "loop.forwarding_address",
FT_ETHER, BASE_NONE, NULL, 0x0,
NULL, HFILL }},
};
static gint *ett[] = {
&ett_loop,
};
proto_loop = proto_register_protocol("Configuration Test Protocol (loopback)",
"LOOP", "loop");
proto_register_field_array(proto_loop, hf, array_length(hf));
proto_register_subtree_array(ett, array_length(ett));
}
void
proto_reg_handoff_loop(void)
{
dissector_handle_t loop_handle;
loop_handle = create_dissector_handle(dissect_loop, proto_loop);
dissector_add_uint("ethertype", ETHERTYPE_LOOP, loop_handle);
data_handle = find_dissector("data");
}
/*
* Editor modelines - http://www.wireshark.org/tools/modelines.html
*
* Local Variables:
* c-basic-offset: 2
* tab-width: 8
* indent-tabs-mode: nil
* End:
*
* ex: set shiftwidth=2 tabstop=8 expandtab:
* :indentSize=2:tabSize=8:noTabs=true:
*/
|
