aboutsummaryrefslogtreecommitdiffstats
path: root/packet-raw.c
blob: 448d54203d1a9d707e659ef9b42b94013f2c6f57 (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
/* packet-raw.c
 * Routines for raw packet disassembly
 *
 * $Id: packet-raw.c,v 1.35 2002/08/28 21:00:29 jmayer Exp $
 *
 * Ethereal - Network traffic analyzer
 * By Gerald Combs <gerald@ethereal.com>
 *
 * This file created and by Mike Hall <mlh@io.com>
 * Copyright 1998
 *
 * 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 <string.h>
#include <glib.h>
#include <epan/packet.h>
#include "packet-raw.h"
#include "packet-ip.h"
#include "packet-ppp.h"

static int proto_raw = -1;
static gint ett_raw = -1;

static const char zeroes[10];

static dissector_handle_t ip_handle;
static dissector_handle_t ipv6_handle;
static dissector_handle_t data_handle;
static dissector_handle_t ppp_hdlc_handle;

void
capture_raw(const guchar *pd, int len, packet_counts *ld)
{
  /* So far, the only time we get raw connection types are with Linux and
   * Irix PPP connections.  We can't tell what type of data is coming down
   * the line, so our safest bet is IP. - GCC
   */

  /* Currently, the Linux 2.1.xxx PPP driver passes back some of the header
   * sometimes.  This check should be removed when 2.2 is out.
   */
  if (BYTES_ARE_IN_FRAME(0,len,2) && pd[0] == 0xff && pd[1] == 0x03) {
    capture_ppp_hdlc(pd, 0, len, ld);
  }
  /* The Linux ISDN driver sends a fake MAC address before the PPP header
   * on its ippp interfaces... */
  else if (BYTES_ARE_IN_FRAME(0,len,8) && pd[6] == 0xff && pd[7] == 0x03) {
    capture_ppp_hdlc(pd, 6, len, ld);
  }
  /* ...except when it just puts out one byte before the PPP header... */
  else if (BYTES_ARE_IN_FRAME(0,len,3) && pd[1] == 0xff && pd[2] == 0x03) {
    capture_ppp_hdlc(pd, 1, len, ld);
  }
  /* ...and if the connection is currently down, it sends 10 bytes of zeroes
   * instead of a fake MAC address and PPP header. */
  else if (BYTES_ARE_IN_FRAME(0,len,10) && memcmp(pd, zeroes, 10) == 0) {
    capture_ip(pd, 10, len, ld);
  }
  else {
    /*
     * OK, is this IPv4 or IPv6?
     */
    if (BYTES_ARE_IN_FRAME(0,len,1)) {
      switch (pd[0] & 0xF0) {

      case 0x40:
        /* IPv4 */
        capture_ip(pd, 0, len, ld);
        break;

#if 0
      case 0x60:
        /* IPv6 */
        capture_ipv6(pd, 0, len, ld);
        break;
#endif
      }
    }
  }
}

static void
dissect_raw(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
{
  proto_tree	*fh_tree;
  proto_item	*ti;
  tvbuff_t	*next_tvb;

  /* load the top pane info. This should be overwritten by
     the next protocol in the stack */
  if(check_col(pinfo->cinfo, COL_RES_DL_SRC))
    col_set_str(pinfo->cinfo, COL_RES_DL_SRC, "N/A" );
  if(check_col(pinfo->cinfo, COL_RES_DL_DST))
    col_set_str(pinfo->cinfo, COL_RES_DL_DST, "N/A" );
  if(check_col(pinfo->cinfo, COL_PROTOCOL))
    col_set_str(pinfo->cinfo, COL_PROTOCOL, "N/A" );
  if(check_col(pinfo->cinfo, COL_INFO))
    col_set_str(pinfo->cinfo, COL_INFO, "Raw packet data" );

  /* populate a tree in the second pane with the status of the link
     layer (ie none) */
  if (tree) {
    ti = proto_tree_add_item(tree, proto_raw, tvb, 0, 0, FALSE);
    fh_tree = proto_item_add_subtree(ti, ett_raw);
    proto_tree_add_text(fh_tree, tvb, 0, 0, "No link information available");
  }

  /* So far, the only time we get raw connection types are with Linux and
   * Irix PPP connections.  We can't tell what type of data is coming down
   * the line, so our safest bet is IP. - GCC
   */

  /* Currently, the Linux 2.1.xxx PPP driver passes back some of the header
   * sometimes.  This check should be removed when 2.2 is out.
   */
  if (tvb_get_ntohs(tvb, 0) == 0xff03) {
	call_dissector(ppp_hdlc_handle, tvb, pinfo, tree);
  }
  /* The Linux ISDN driver sends a fake MAC address before the PPP header
   * on its ippp interfaces... */
  else if (tvb_get_ntohs(tvb, 6) == 0xff03) {
	next_tvb = tvb_new_subset(tvb, 6, -1, -1);
	call_dissector(ppp_hdlc_handle, next_tvb, pinfo, tree);
  }
  /* ...except when it just puts out one byte before the PPP header... */
  else if (tvb_get_ntohs(tvb, 1) == 0xff03) {
	next_tvb = tvb_new_subset(tvb, 1, -1, -1);
	call_dissector(ppp_hdlc_handle, next_tvb, pinfo, tree);
  }
  /* ...and if the connection is currently down, it sends 10 bytes of zeroes
   * instead of a fake MAC address and PPP header. */
  else if (memcmp(tvb_get_ptr(tvb, 0, 10), zeroes, 10) == 0) {
	next_tvb = tvb_new_subset(tvb, 10, -1, -1);
	call_dissector(ip_handle, next_tvb, pinfo, tree);
  }
  else {
	/*
	 * OK, is this IPv4 or IPv6?
	 */
	switch (tvb_get_guint8(tvb, 0) & 0xF0) {

	case 0x40:
	  /* IPv4 */
	  call_dissector(ip_handle, tvb, pinfo, tree);
	  break;

	case 0x60:
	  /* IPv6 */
	  call_dissector(ipv6_handle, tvb, pinfo, tree);
	  break;

	default:
	  /* None of the above. */
	  call_dissector(data_handle, tvb, pinfo, tree);
	  break;
	}
  }
}

void
proto_register_raw(void)
{
  static gint *ett[] = {
    &ett_raw,
  };

  proto_raw = proto_register_protocol("Raw packet data", "Raw", "raw");
  proto_register_subtree_array(ett, array_length(ett));
}

void
proto_reg_handoff_raw(void)
{
  dissector_handle_t raw_handle;

  /*
   * Get handles for the IP, IPv6, undissected-data, and
   * PPP-in-HDLC-like-framing dissectors.
   */
  ip_handle = find_dissector("ip");
  ipv6_handle = find_dissector("ipv6");
  data_handle = find_dissector("data");
  ppp_hdlc_handle = find_dissector("ppp_hdlc");
  raw_handle = create_dissector_handle(dissect_raw, proto_raw);
  dissector_add("wtap_encap", WTAP_ENCAP_RAW_IP, raw_handle);
}