summaryrefslogtreecommitdiffstats
path: root/epan/dissectors/packet-fcgi.c
blob: cd43dd1135f8b7cb7f31af63d5db4943df01933e (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
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
/* packet-fcgi.c
 * Routines for FastCGI dissection
 * Copyright 2010, Tom Hughes <tom@compton.nu>
 *
 * Wireshark - Network traffic analyzer
 * By Gerald Combs <gerald@wireshark.org>
 * Copyright 1998 Gerald Combs
 *
 * SPDX-License-Identifier: GPL-2.0-or-later
 */

#include "config.h"

#include <epan/packet.h>
#include "packet-tcp.h"

void proto_register_fcgi(void);
void proto_reg_handoff_fcgi(void);

static int proto_fcgi = -1;

static int hf_fcgi_version = -1;
static int hf_fcgi_type = -1;
static int hf_fcgi_id = -1;
static int hf_fcgi_content_length = -1;
static int hf_fcgi_padding_length = -1;
static int hf_fcgi_content_data = -1;
static int hf_fcgi_padding_data = -1;
static int hf_fcgi_begin_request_role = -1;
static int hf_fcgi_begin_request_flags = -1;
static int hf_fcgi_begin_request_keep_conn = -1;
static int hf_fcgi_end_request_app_status = -1;
static int hf_fcgi_end_request_protocol_status = -1;
static int hf_fcgi_nv_name = -1;

static int ett_fcgi = -1;
static int ett_fcgi_begin_request = -1;
static int ett_fcgi_abort_request = -1;
static int ett_fcgi_end_request = -1;
static int ett_fcgi_params = -1;

static dissector_handle_t fcgi_handle;

#define FCGI_BEGIN_REQUEST       1
#define FCGI_ABORT_REQUEST       2
#define FCGI_END_REQUEST         3
#define FCGI_PARAMS              4
#define FCGI_STDIN               5
#define FCGI_STDOUT              6
#define FCGI_STDERR              7
#define FCGI_DATA                8
#define FCGI_GET_VALUES          9
#define FCGI_GET_VALUES_RESULT  10
#define FCGI_UNKNOWN_TYPE       11

static const value_string record_types[] = {
   { 1, "FCGI_BEGIN_REQUEST" },
   { 2, "FCGI_ABORT_REQUEST" },
   { 3, "FCGI_END_REQUEST" },
   { 4, "FCGI_PARAMS" },
   { 5, "FCGI_STDIN" },
   { 6, "FCGI_STDOUT" },
   { 7, "FCGI_STDERR" },
   { 8, "FCGI_DATA" },
   { 9, "FCGI_GET_VALUES" },
   { 10, "FCGI_GET_VALUES_RESULT" },
   { 11, "FCGI_UNKNOWN_TYPE" },
   { 0, NULL }
};

static const value_string application_roles[] = {
   { 1, "FCGI_RESPONDER" },
   { 2, "FCGI_AUTHORIZER" },
   { 3, "FCGI_FILTER" },
   { 0, NULL }
};

#define FCGI_KEEP_CONN  1

static const value_string protocol_statuses[] = {
   { 0, "FCGI_REQUEST_COMPLETE" },
   { 1, "FCGI_CANT_MPX_CONN" },
   { 2, "FCGI_OVERLOADED" },
   { 3, "FCGI_UNKNOWN_ROLE" },
   { 0, NULL }
};

static void
dissect_nv_pairs(tvbuff_t *tvb, packet_info *pinfo, proto_tree *fcgi_tree, gint offset, guint16 len)
{
   gint end_offset = offset + len;

   while (offset < end_offset) {
      gint start_offset = offset;
      guint32 namelen;
      guint32 valuelen;
      char *name;
      char *value;

      namelen = tvb_get_guint8(tvb, offset);
      if ((namelen & 0x80) == 0) {
         offset += 1;
      } else {
         namelen = tvb_get_ntohl(tvb, offset) & 0x7FFFFFFF;
         offset += 4;
      }

      valuelen = tvb_get_guint8(tvb, offset);
      if ((valuelen & 0x80) == 0) {
         offset += 1;
      } else {
         valuelen = tvb_get_ntohl(tvb, offset) & 0x7FFFFFFF;
         offset += 4;
      }

      name = tvb_get_string_enc(pinfo->pool, tvb, offset, namelen, ENC_ASCII);
      offset += namelen;

      if (valuelen > 0) {
         value = tvb_get_string_enc(pinfo->pool, tvb, offset, valuelen, ENC_ASCII);
         offset += valuelen;

         proto_tree_add_string_format(fcgi_tree, hf_fcgi_nv_name, tvb, start_offset, offset - start_offset,
                            name, "%s = %s", name, value);
      } else {
         proto_tree_add_string_format(fcgi_tree, hf_fcgi_nv_name, tvb, start_offset, offset - start_offset,
                            name, "%s", name);
      }
   }
}

static int
dissect_begin_request(tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *fcgi_tree, gint offset, guint16 len)
{
   proto_tree *br_tree;

   br_tree = proto_tree_add_subtree(fcgi_tree, tvb, offset, len, ett_fcgi_begin_request, NULL, "Begin Request:");

   proto_tree_add_item(br_tree, hf_fcgi_begin_request_role, tvb, offset, 2, ENC_BIG_ENDIAN);
   offset += 2;

   proto_tree_add_item(br_tree, hf_fcgi_begin_request_flags, tvb, offset, 1, ENC_BIG_ENDIAN);
   proto_tree_add_item(br_tree, hf_fcgi_begin_request_keep_conn, tvb, offset, 1, ENC_BIG_ENDIAN);
   offset += 1;

   offset += 5;

   return offset;
}

static void
dissect_abort_request(tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *fcgi_tree, gint offset, guint16 len)
{
   proto_tree_add_subtree(fcgi_tree, tvb, offset, len, ett_fcgi_abort_request, NULL, "Abort Request:");

   return;
}

static int
dissect_end_request(tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *fcgi_tree, gint offset, guint16 len)
{
   proto_tree *er_tree;

   er_tree = proto_tree_add_subtree(fcgi_tree, tvb, offset, len, ett_fcgi_end_request, NULL, "End Request:");

   proto_tree_add_item(er_tree, hf_fcgi_end_request_app_status, tvb, offset, 4, ENC_BIG_ENDIAN);
   offset += 4;

   proto_tree_add_item(er_tree, hf_fcgi_end_request_protocol_status, tvb, offset, 1, ENC_BIG_ENDIAN);
   offset += 1;

   offset += 3;

   return offset;
}

static void
dissect_params(tvbuff_t *tvb, packet_info *pinfo, proto_tree *fcgi_tree, gint offset, guint16 len)
{
   proto_tree *p_tree;

   p_tree = proto_tree_add_subtree(fcgi_tree, tvb, offset, len, ett_fcgi_params, NULL, "Params:");

   dissect_nv_pairs(tvb, pinfo, p_tree, offset, len);

   return;
}

static void
dissect_get_values(tvbuff_t *tvb, packet_info *pinfo, proto_tree *fcgi_tree, gint offset, guint16 len)
{
   proto_tree *gv_tree;

   gv_tree = proto_tree_add_subtree(fcgi_tree, tvb, offset, len, ett_fcgi_params, NULL, "Get Values:");

   dissect_nv_pairs(tvb, pinfo, gv_tree, offset, len);

   return;
}

static void
dissect_get_values_result(tvbuff_t *tvb, packet_info *pinfo, proto_tree *fcgi_tree, gint offset, guint16 len)
{
   proto_tree *gvr_tree;

   gvr_tree = proto_tree_add_subtree(fcgi_tree, tvb, offset, len, ett_fcgi_params, NULL, "Get Values:");

   dissect_nv_pairs(tvb, pinfo, gvr_tree, offset, len);

   return;
}

static int
dissect_fcgi_record(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_)
{
   gint offset = 0;
   guint8 type;

   type = tvb_get_guint8(tvb, 1);

   /* When there are multiple FCGI records in a TCP frame the following code */
   /* will append the type for each record to COL_INFO.                      */
   /* XXX: Unfortunately, something in the tcp_dissect_pdus() code is broken */
   /*      such that only the type for the first FCGI record appears in the  */
   /*      INFO column. (All write attempts to COL_INFO after the first fail */
   /*      because pinfo->cinfo->writable is FALSE).                         */
   col_set_str(pinfo->cinfo, COL_PROTOCOL, "FCGI");
   col_clear(pinfo->cinfo, COL_INFO);
   col_append_sep_str(pinfo->cinfo, COL_INFO, NULL,
                      val_to_str(type, record_types, "Unknown (%u)"));
   col_set_fence(pinfo->cinfo, COL_INFO);

   if (tree) { /* we are being asked for details */
      proto_item *ti;
      proto_tree *fcgi_tree;
      guint16 clen;
      guint8 plen;

      ti = proto_tree_add_item(tree, proto_fcgi, tvb, 0, -1, ENC_NA);
      proto_item_append_text(ti, " (%s)",
                             val_to_str(type, record_types, "Unknown (%u)"));
      fcgi_tree = proto_item_add_subtree(ti, ett_fcgi);

      proto_tree_add_item(fcgi_tree, hf_fcgi_version, tvb, offset, 1, ENC_BIG_ENDIAN);
      offset += 1;

      proto_tree_add_item(fcgi_tree, hf_fcgi_type, tvb, offset, 1, ENC_BIG_ENDIAN);
      offset += 1;

      proto_tree_add_item(fcgi_tree, hf_fcgi_id, tvb, offset, 2, ENC_BIG_ENDIAN);
      offset += 2;

      clen = tvb_get_ntohs(tvb, offset);
      proto_tree_add_item(fcgi_tree, hf_fcgi_content_length, tvb, offset, 2, ENC_BIG_ENDIAN);
      offset += 2;

      plen = tvb_get_guint8(tvb, offset);
      proto_tree_add_item(fcgi_tree, hf_fcgi_padding_length, tvb, offset, 1, ENC_BIG_ENDIAN);
      offset += 1;

      offset += 1;

      switch (type)
      {
      case FCGI_BEGIN_REQUEST:
         dissect_begin_request(tvb, pinfo, fcgi_tree, offset, clen);
         offset += clen;
         break;
      case FCGI_ABORT_REQUEST:
         dissect_abort_request(tvb, pinfo, fcgi_tree, offset, clen);
         offset += clen;
         break;
      case FCGI_END_REQUEST:
         dissect_end_request(tvb, pinfo, fcgi_tree, offset, clen);
         offset += clen;
         break;
      case FCGI_PARAMS:
         dissect_params(tvb, pinfo, fcgi_tree, offset, clen);
         offset += clen;
         break;
      case FCGI_GET_VALUES:
         dissect_get_values(tvb, pinfo, fcgi_tree, offset, clen);
         offset += clen;
         break;
      case FCGI_GET_VALUES_RESULT:
         dissect_get_values_result(tvb, pinfo, fcgi_tree, offset, clen);
         offset += clen;
         break;
      default:
         if (clen > 0) {
            proto_tree_add_item(fcgi_tree, hf_fcgi_content_data, tvb, offset, clen, ENC_NA);
            offset += clen;
         }
         break;
      }

      if (plen > 0) {
         proto_tree_add_item(fcgi_tree, hf_fcgi_padding_data, tvb, offset, plen, ENC_NA);
         /*offset += plen;*/
      }
   }

   return tvb_captured_length(tvb);
}

static guint
get_fcgi_record_len(packet_info *pinfo _U_, tvbuff_t *tvb, int offset, void *data _U_)
{
   return 8 + tvb_get_ntohs(tvb, offset + 4) + tvb_get_guint8(tvb, offset + 6);
}

static int
dissect_fcgi(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data)
{
   tcp_dissect_pdus(tvb, pinfo, tree, TRUE, 8, get_fcgi_record_len, dissect_fcgi_record, data);
   return tvb_captured_length(tvb);
}

void
proto_register_fcgi(void)
{
   static hf_register_info hf[] = {
      { &hf_fcgi_version,
        { "Version", "fcgi.version",
          FT_UINT8, BASE_DEC, NULL, 0x0, NULL, HFILL } },
      { &hf_fcgi_type,
        { "Type", "fcgi.type",
          FT_UINT8, BASE_DEC, VALS(record_types), 0x0, NULL, HFILL } },
      { &hf_fcgi_id,
        { "Request ID", "fcgi.id",
          FT_UINT16, BASE_DEC, NULL, 0x0, NULL, HFILL } },
      { &hf_fcgi_content_length,
        { "Content Length", "fcgi.content.length",
          FT_UINT16, BASE_DEC, NULL, 0x0, NULL, HFILL } },
      { &hf_fcgi_padding_length,
        { "Padding Length", "fcgi.padding.length",
          FT_UINT8, BASE_DEC, NULL, 0x0, NULL, HFILL } },
      { &hf_fcgi_content_data,
        { "Content Data", "fcgi.content.data",
          FT_BYTES, BASE_NONE, NULL, 0x0, NULL, HFILL } },
      { &hf_fcgi_padding_data,
        { "Padding Data", "fcgi.padding.data",
          FT_BYTES, BASE_NONE, NULL, 0x0, NULL, HFILL } },
      { &hf_fcgi_begin_request_role,
        { "Role", "fcgi.begin_request.role",
          FT_UINT16, BASE_DEC, VALS(application_roles), 0x0, NULL, HFILL } },
      { &hf_fcgi_begin_request_flags,
        { "Flags", "fcgi.begin_request.flags",
          FT_UINT8, BASE_HEX, NULL, 0x0, NULL, HFILL } },
      { &hf_fcgi_begin_request_keep_conn,
        { "FCGI_KEEP_CONN", "fcgi.begin_request.keep_conn",
          FT_BOOLEAN, 8, NULL, FCGI_KEEP_CONN, NULL, HFILL } },
      { &hf_fcgi_end_request_app_status,
        { "Application Status", "fcgi.end_request.app_status",
          FT_UINT32, BASE_DEC, NULL, 0x0, NULL, HFILL } },
      { &hf_fcgi_end_request_protocol_status,
        { "Protocol Status", "fcgi.end_request.protocol_status",
          FT_UINT32, BASE_DEC, VALS(protocol_statuses), 0x0, NULL, HFILL } },
      { &hf_fcgi_nv_name,
        { "NV Pair name", "fcgi.nv_name",
          FT_STRING, BASE_NONE, NULL, 0x0, NULL, HFILL } },
   };
   static gint *ett[] = {
      &ett_fcgi,
      &ett_fcgi_begin_request,
      &ett_fcgi_abort_request,
      &ett_fcgi_end_request,
      &ett_fcgi_params
   };

   proto_fcgi = proto_register_protocol("FastCGI", "FCGI", "fcgi");

   proto_register_field_array(proto_fcgi, hf, array_length(hf));
   proto_register_subtree_array(ett, array_length(ett));

   fcgi_handle = register_dissector("fcgi", dissect_fcgi, proto_fcgi);
}

void
proto_reg_handoff_fcgi(void)
{
   dissector_add_for_decode_as_with_preference("tcp.port", fcgi_handle);
}

/*
 * Editor modelines  -  https://www.wireshark.org/tools/modelines.html
 *
 * Local Variables:
 * c-basic-offset: 3
 * tab-width: 8
 * indent-tabs-mode: nil
 * End:
 *
 * ex: set shiftwidth=3 tabstop=8 expandtab:
 * :indentSize=3:tabSize=8:noTabs=true:
 */