2 * Routines for raw packet disassembly
4 * $Id: packet-raw.c,v 1.36 2003/08/26 05:52:52 guy Exp $
6 * Ethereal - Network traffic analyzer
7 * By Gerald Combs <gerald@ethereal.com>
9 * This file created and by Mike Hall <mlh@io.com>
12 * This program is free software; you can redistribute it and/or
13 * modify it under the terms of the GNU General Public License
14 * as published by the Free Software Foundation; either version 2
15 * of the License, or (at your option) any later version.
17 * This program is distributed in the hope that it will be useful,
18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20 * GNU General Public License for more details.
22 * You should have received a copy of the GNU General Public License
23 * along with this program; if not, write to the Free Software
24 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
33 #include <epan/packet.h>
35 #include "packet-raw.h"
36 #include "packet-ip.h"
37 #include "packet-ppp.h"
39 static int proto_raw = -1;
40 static gint ett_raw = -1;
42 static const char zeroes[10];
44 static dissector_handle_t ip_handle;
45 static dissector_handle_t ipv6_handle;
46 static dissector_handle_t data_handle;
47 static dissector_handle_t ppp_hdlc_handle;
50 capture_raw(const guchar *pd, int len, packet_counts *ld)
52 /* So far, the only time we get raw connection types are with Linux and
53 * Irix PPP connections. We can't tell what type of data is coming down
54 * the line, so our safest bet is IP. - GCC
57 /* Currently, the Linux 2.1.xxx PPP driver passes back some of the header
58 * sometimes. This check should be removed when 2.2 is out.
60 if (BYTES_ARE_IN_FRAME(0,len,2) && pd[0] == 0xff && pd[1] == 0x03) {
61 capture_ppp_hdlc(pd, 0, len, ld);
63 /* The Linux ISDN driver sends a fake MAC address before the PPP header
64 * on its ippp interfaces... */
65 else if (BYTES_ARE_IN_FRAME(0,len,8) && pd[6] == 0xff && pd[7] == 0x03) {
66 capture_ppp_hdlc(pd, 6, len, ld);
68 /* ...except when it just puts out one byte before the PPP header... */
69 else if (BYTES_ARE_IN_FRAME(0,len,3) && pd[1] == 0xff && pd[2] == 0x03) {
70 capture_ppp_hdlc(pd, 1, len, ld);
72 /* ...and if the connection is currently down, it sends 10 bytes of zeroes
73 * instead of a fake MAC address and PPP header. */
74 else if (BYTES_ARE_IN_FRAME(0,len,10) && memcmp(pd, zeroes, 10) == 0) {
75 capture_ip(pd, 10, len, ld);
79 * OK, is this IPv4 or IPv6?
81 if (BYTES_ARE_IN_FRAME(0,len,1)) {
82 switch (pd[0] & 0xF0) {
86 capture_ip(pd, 0, len, ld);
92 capture_ipv6(pd, 0, len, ld);
101 dissect_raw(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
107 /* load the top pane info. This should be overwritten by
108 the next protocol in the stack */
109 if(check_col(pinfo->cinfo, COL_RES_DL_SRC))
110 col_set_str(pinfo->cinfo, COL_RES_DL_SRC, "N/A" );
111 if(check_col(pinfo->cinfo, COL_RES_DL_DST))
112 col_set_str(pinfo->cinfo, COL_RES_DL_DST, "N/A" );
113 if(check_col(pinfo->cinfo, COL_PROTOCOL))
114 col_set_str(pinfo->cinfo, COL_PROTOCOL, "N/A" );
115 if(check_col(pinfo->cinfo, COL_INFO))
116 col_set_str(pinfo->cinfo, COL_INFO, "Raw packet data" );
118 /* populate a tree in the second pane with the status of the link
121 ti = proto_tree_add_item(tree, proto_raw, tvb, 0, 0, FALSE);
122 fh_tree = proto_item_add_subtree(ti, ett_raw);
123 proto_tree_add_text(fh_tree, tvb, 0, 0, "No link information available");
126 /* So far, the only time we get raw connection types are with Linux and
127 * Irix PPP connections. We can't tell what type of data is coming down
128 * the line, so our safest bet is IP. - GCC
131 /* Currently, the Linux 2.1.xxx PPP driver passes back some of the header
132 * sometimes. This check should be removed when 2.2 is out.
134 if (tvb_get_ntohs(tvb, 0) == 0xff03) {
135 call_dissector(ppp_hdlc_handle, tvb, pinfo, tree);
137 /* The Linux ISDN driver sends a fake MAC address before the PPP header
138 * on its ippp interfaces... */
139 else if (tvb_get_ntohs(tvb, 6) == 0xff03) {
140 next_tvb = tvb_new_subset(tvb, 6, -1, -1);
141 call_dissector(ppp_hdlc_handle, next_tvb, pinfo, tree);
143 /* ...except when it just puts out one byte before the PPP header... */
144 else if (tvb_get_ntohs(tvb, 1) == 0xff03) {
145 next_tvb = tvb_new_subset(tvb, 1, -1, -1);
146 call_dissector(ppp_hdlc_handle, next_tvb, pinfo, tree);
148 /* ...and if the connection is currently down, it sends 10 bytes of zeroes
149 * instead of a fake MAC address and PPP header. */
150 else if (memcmp(tvb_get_ptr(tvb, 0, 10), zeroes, 10) == 0) {
151 next_tvb = tvb_new_subset(tvb, 10, -1, -1);
152 call_dissector(ip_handle, next_tvb, pinfo, tree);
156 * OK, is this IPv4 or IPv6?
158 switch (tvb_get_guint8(tvb, 0) & 0xF0) {
162 call_dissector(ip_handle, tvb, pinfo, tree);
167 call_dissector(ipv6_handle, tvb, pinfo, tree);
171 /* None of the above. */
172 call_dissector(data_handle, tvb, pinfo, tree);
179 proto_register_raw(void)
181 static gint *ett[] = {
185 proto_raw = proto_register_protocol("Raw packet data", "Raw", "raw");
186 proto_register_subtree_array(ett, array_length(ett));
190 proto_reg_handoff_raw(void)
192 dissector_handle_t raw_handle;
195 * Get handles for the IP, IPv6, undissected-data, and
196 * PPP-in-HDLC-like-framing dissectors.
198 ip_handle = find_dissector("ip");
199 ipv6_handle = find_dissector("ipv6");
200 data_handle = find_dissector("data");
201 ppp_hdlc_handle = find_dissector("ppp_hdlc");
202 raw_handle = create_dissector_handle(dissect_raw, proto_raw);
203 dissector_add("wtap_encap", WTAP_ENCAP_RAW_IP, raw_handle);