summaryrefslogtreecommitdiffstats
path: root/epan/dissectors/packet-fw1.c
blob: a9e42ebad5d318121ac5357bf463a4ab9e2ac3f8 (plain)
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
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
/* packet-fw1.c
 * Routines for Ethernet header disassembly of FW1 "monitor" files
 * Copyright 2002,2003, Alfred Koebler <ako@icon.de>
 * Copyright 2018, Alfred Koebler <Alfred.Koebler2002ATgmx.de>
 *
 * Wireshark - Network traffic analyzer
 * By Alfred Koebler <ako@icon.de>
 * By Alfred Koebler <Alfred.Koebler2002ATgmx.de>
 * Copyright 2002,2003,2018 Alfred Koebler
 *
 * To use this dissector use the command line option
 * -o eth.interpret_as_fw1_monitor:TRUE
 *
 * At the moment the way with the option is the best one.
 * A automatic way is not possible, because the file format isn't different
 * to the snoop file.
 *
 * With "fw monitor" it is possible to collect packets on several places.
 * The additional information:
 * - is it a incoming or outgoing packet
 * - is it before or after the firewall
 *   i  incoming before the firewall
 *   I  incoming after the firewall
 *   o  outcoming before the firewall
 *   O  outcoming after the firewall
 *   e  before VPN encryption
 *   E  after VPN encryption
 * - the name of the interface
 *
 * What's the problem ?
 * Think about one packet traveling across the firewall.
 * With wireshark you will see 4 lines in the Top Pane.
 * To analyze a problem it is helpful to see the additional information
 * in the protocol tree of the Middle Pane.
 *
 * The presentation of the summary line is designed in the following way:
 * Every time the next selected packet in the Top Pane includes a
 * "new" interface name the name is added to the list in the summary line.
 * The interface names are listed one after the other.
 * The position of the interface names didn't change.
 *
 * And who are the 4 places represented ?
 * The interface name represents the firewall module of the interface.
 * On the left side of the interface name is the interface module.
 * On the right side of the interface name is the "IP" module.
 *
 * Example for a ping from the firewall to another host:
 * For the four lines in the Top Pane you will see the according lines
 * in the Middle Pane:
 *   El90x1 o
 * O El90x1
 * i El90x1
 *   El90x1 I
 *
 * Example for a packet traversing through the Firewall, first through
 * the inner side firewall module then through the outer side firewall module:
 * i  El90x1        El90x2
 *    El90x1 I      El90x2
 *    El90x1      o E190x2
 *    El90x1        E190x2 O
 *
 * 9.12.2002
 * Add new column with summary of FW-1 interface/direction
 *
 * 11.8.2003
 * Additional interpretation of field Chain Position.
 * Show the chain position in the interface list.
 * Support for new format of fw monitor file
 * writen by option -u | -s for UUID/SUUID.
 * NOTICE: First paket will have UUID == 0 !
 *
 * SPDX-License-Identifier: GPL-2.0-or-later
 *
 * 30.5.2018
 * added inspection points "e" and "E"
 */

#include "config.h"


#include <epan/packet.h>
#include <epan/prefs.h>
#include <epan/etypes.h>

void proto_register_fw1(void);
void proto_reg_handoff_fw1(void);

/* Place FW1 summary in proto tree */
static gboolean fw1_summary_in_tree = TRUE;
static gboolean fw1_with_uuid = FALSE;
static gboolean fw1_iflist_with_chain = FALSE;

static dissector_handle_t ethertype_handle;

/* Initialize the protocol and registered fields */
static int proto_fw1 = -1;
static int hf_fw1_direction = -1;
static int hf_fw1_chain = -1;
static int hf_fw1_interface = -1;
static int hf_fw1_uuid = -1;
static int hf_fw1_type = -1;
static int hf_fw1_trailer = -1;

/* Initialize the subtree pointers */
static gint ett_fw1 = -1;

#define ETH_HEADER_SIZE 14

#define MAX_INTERFACES  20
static gchar    *p_interfaces[MAX_INTERFACES];
static int      interface_anzahl=0;

static void
fw1_init(void)
{
  interface_anzahl = 0;
}

static int
dissect_fw1(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_)
{
  /* Set up structures needed to add the protocol subtree and manage it */
  proto_item    *ti;
  proto_tree    *fh_tree = NULL;
  char          direction;
  char  chain;
  char          *interface_name;
  guint32       iface_len = 10;
  wmem_strbuf_t *header;
  int           i;
  gboolean      found;
  static const char     fw1_header[] = "FW1 Monitor";
  ethertype_data_t ethertype_data;

  header = wmem_strbuf_create(pinfo->pool);
  wmem_strbuf_append(header, fw1_header);

  /* Make entries in Protocol column and Info column on summary display */
  col_set_str(pinfo->cinfo, COL_PROTOCOL, "FW1");
  col_clear(pinfo->cinfo, COL_INFO);

  /* fetch info to local variable */
  direction = tvb_get_guint8(tvb, 0);

  if (!fw1_iflist_with_chain)
    chain = ' ';
  else
    chain = tvb_get_guint8(tvb, 1);

  if (fw1_with_uuid)
    iface_len = 6;

  interface_name=tvb_get_stringzpad(pinfo->pool, tvb, 2, iface_len, ENC_ASCII|ENC_NA);

  /* Known interface name - if not, remember it */
  found=FALSE;
  for (i=0; i<interface_anzahl; i++) {
    if ( strcmp(p_interfaces[i], interface_name) == 0 ) {
      found=TRUE;
      break;
    }
  }
  if (!found && interface_anzahl < MAX_INTERFACES) {
    p_interfaces[interface_anzahl] = wmem_strdup(wmem_file_scope(), interface_name);
    interface_anzahl++;
  }

  /* display all interfaces always in the same order */
  for (i=0; i<interface_anzahl; i++) {
    if ( strcmp(p_interfaces[i], interface_name) == 0 ) {
      wmem_strbuf_append_printf(header, "  %c%c %s %c%c",
                                direction == 'i' ? 'i' : (direction == 'O' ? 'O' : (direction == 'E' ? 'E' :  ' ') ),
                                (direction == 'i' || direction == 'O' || direction == 'E') ? chain : ' ',
                                p_interfaces[i],
                                direction == 'I' ? 'I' : (direction == 'o' ? 'o' : (direction == 'e' ? 'e' :  ' ') ),
                                (direction == 'I' || direction == 'o' || direction == 'e') ? chain : ' '
        );
    } else {
      wmem_strbuf_append_printf(header, "    %s  ", p_interfaces[i]);
    }
  }

  col_add_str(pinfo->cinfo, COL_IF_DIR, wmem_strbuf_get_str(header) + sizeof(fw1_header) + 1);

  if (tree) {
    if (!fw1_summary_in_tree)
      /* Do not show the summary in Protocol Tree */
      ti = proto_tree_add_protocol_format(tree, proto_fw1, tvb, 0, ETH_HEADER_SIZE, "%s", fw1_header);
    else
      ti = proto_tree_add_protocol_format(tree, proto_fw1, tvb, 0, ETH_HEADER_SIZE, "%s", wmem_strbuf_get_str(header));

    /* create display subtree for the protocol */
    fh_tree = proto_item_add_subtree(ti, ett_fw1);

    proto_tree_add_item(fh_tree, hf_fw1_direction, tvb, 0, 1, ENC_ASCII);

    if (fw1_iflist_with_chain)
      proto_tree_add_item(fh_tree, hf_fw1_chain, tvb, 1, 1, ENC_ASCII);

    proto_tree_add_item(fh_tree, hf_fw1_interface, tvb, 2, iface_len, ENC_ASCII);

    if (fw1_with_uuid)
      proto_tree_add_item(fh_tree, hf_fw1_uuid, tvb, 8, 4, ENC_BIG_ENDIAN);
  }

  ethertype_data.etype = tvb_get_ntohs(tvb, 12);
  proto_tree_add_uint(fh_tree, hf_fw1_type, tvb, 12, 2, ethertype_data.etype);

  ethertype_data.payload_offset = ETH_HEADER_SIZE;
  ethertype_data.fh_tree = fh_tree;
  ethertype_data.trailer_id = hf_fw1_trailer;
  ethertype_data.fcs_len = 0;

  call_dissector_with_data(ethertype_handle, tvb, pinfo, tree, &ethertype_data);
  return tvb_captured_length(tvb);
}

void
proto_register_fw1(void)
{
  static hf_register_info hf[] = {
    { &hf_fw1_direction,
      { "Direction", "fw1.direction", FT_STRING, BASE_NONE, NULL, 0x0,
        NULL, HFILL }},

    { &hf_fw1_chain,
      { "Chain Position", "fw1.chain", FT_STRING, BASE_NONE, NULL, 0x0,
        NULL, HFILL }},

    { &hf_fw1_interface,
      { "Interface", "fw1.interface", FT_STRING, BASE_NONE, NULL, 0x0,
        NULL, HFILL }},

    { &hf_fw1_uuid,
      { "UUID", "fw1.uuid", FT_UINT32, BASE_DEC, NULL, 0x0,
        NULL, HFILL }},

    /* registered here but handled in ethertype.c */
    { &hf_fw1_type,
      { "Type", "fw1.type", FT_UINT16, BASE_HEX, VALS(etype_vals), 0x0,
        NULL, HFILL }},

    { &hf_fw1_trailer,
      { "Trailer", "fw1.trailer", FT_BYTES, BASE_NONE, NULL, 0x0,
        NULL, HFILL }
    }
  };
  /* Setup protocol subtree array */
  static gint *ett[] = {
    &ett_fw1,
  };
  module_t *fw1_module;
  int       i;

  /* Register the protocol name and description */
  proto_fw1 = proto_register_protocol("Checkpoint FW-1", "FW-1", "fw1");
  /* Required function calls to register the header fields and subtrees used */
  proto_register_field_array(proto_fw1, hf, array_length(hf));
  proto_register_subtree_array(ett, array_length(ett));

  /* Register configuration preferences */
  fw1_module = prefs_register_protocol(proto_fw1, NULL);
  prefs_register_bool_preference(fw1_module, "summary_in_tree",
                                 "Show FireWall-1 summary in protocol tree",
                                 "Whether the FireWall-1 summary line should be shown in the protocol tree",
                                 &fw1_summary_in_tree);
  prefs_register_bool_preference(fw1_module, "with_uuid",
                                 "Monitor file includes UUID",
                                 "Whether the Firewall-1 monitor file includes UUID information",
                                 &fw1_with_uuid);
  prefs_register_bool_preference(fw1_module, "iflist_with_chain",
                                 "Interface list includes chain position",
                                 "Whether the interface list includes the chain position",
                                 &fw1_iflist_with_chain);

  register_dissector("fw1", dissect_fw1, proto_fw1);

  for (i=0; i<MAX_INTERFACES; i++) {
    p_interfaces[i] = NULL;
  }
  register_init_routine(fw1_init);
}

void
proto_reg_handoff_fw1(void)
{
    ethertype_handle = find_dissector_add_dependency("ethertype", proto_fw1);
}

/*
 * Editor modelines  -  https://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:
 */