2 * Routines for raw packet disassembly
4 * $Id: packet-raw.c,v 1.25 2001/03/30 06:10:54 guy Exp $
6 * Ethereal - Network traffic analyzer
7 * By Gerald Combs <gerald@zing.org>
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.
31 #ifdef HAVE_SYS_TYPES_H
32 # include <sys/types.h>
38 #include "packet-raw.h"
39 #include "packet-ip.h"
40 #include "packet-ppp.h"
42 static gint ett_raw = -1;
44 static const char zeroes[10];
46 static dissector_handle_t ip_handle;
47 static dissector_handle_t ppp_hdlc_handle;
50 capture_raw(const u_char *pd, 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(0,2) && pd[0] == 0xff && pd[1] == 0x03) {
61 capture_ppp(pd, 0, 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(0,8) && pd[6] == 0xff && pd[7] == 0x03) {
66 capture_ppp(pd, 6, ld);
68 /* ...except when it just puts out one byte before the PPP header... */
69 else if (BYTES_ARE_IN_FRAME(0,3) && pd[1] == 0xff && pd[2] == 0x03) {
70 capture_ppp(pd, 1, 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(0,10) && memcmp(pd, zeroes, 10) == 0) {
75 capture_ip(pd, 10, ld);
78 capture_ip(pd, 0, ld);
83 dissect_raw(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
89 /* load the top pane info. This should be overwritten by
90 the next protocol in the stack */
91 if(check_col(pinfo->fd, COL_RES_DL_SRC))
92 col_set_str(pinfo->fd, COL_RES_DL_SRC, "N/A" );
93 if(check_col(pinfo->fd, COL_RES_DL_DST))
94 col_set_str(pinfo->fd, COL_RES_DL_DST, "N/A" );
95 if(check_col(pinfo->fd, COL_PROTOCOL))
96 col_set_str(pinfo->fd, COL_PROTOCOL, "N/A" );
97 if(check_col(pinfo->fd, COL_INFO))
98 col_set_str(pinfo->fd, COL_INFO, "Raw packet data" );
100 /* populate a tree in the second pane with the status of the link
103 ti = proto_tree_add_text(tree, tvb, 0, 0, "Raw packet data" );
104 fh_tree = proto_item_add_subtree(ti, ett_raw);
105 proto_tree_add_text(fh_tree, tvb, 0, 0, "No link information available");
108 /* So far, the only time we get raw connection types are with Linux and
109 * Irix PPP connections. We can't tell what type of data is coming down
110 * the line, so our safest bet is IP. - GCC
113 /* Currently, the Linux 2.1.xxx PPP driver passes back some of the header
114 * sometimes. This check should be removed when 2.2 is out.
116 if (tvb_get_ntohs(tvb, 0) == 0xff03) {
117 call_dissector(ppp_hdlc_handle, tvb, pinfo, tree);
120 /* The Linux ISDN driver sends a fake MAC address before the PPP header
121 * on its ippp interfaces... */
122 else if (tvb_get_ntohs(tvb, 6) == 0xff03) {
123 next_tvb = tvb_new_subset(tvb, 6, -1, -1);
124 call_dissector(ppp_hdlc_handle, next_tvb, pinfo, tree);
127 /* ...except when it just puts out one byte before the PPP header... */
128 else if (tvb_get_ntohs(tvb, 1) == 0xff03) {
129 next_tvb = tvb_new_subset(tvb, 1, -1, -1);
130 call_dissector(ppp_hdlc_handle, next_tvb, pinfo, tree);
133 /* ...and if the connection is currently down, it sends 10 bytes of zeroes
134 * instead of a fake MAC address and PPP header. */
135 else if (memcmp(tvb_get_ptr(tvb, 0, 10), zeroes, 10) == 0) {
136 next_tvb = tvb_new_subset(tvb, 10, -1, -1);
137 call_dissector(ip_handle, next_tvb, pinfo, tree);
141 next_tvb = tvb_new_subset(tvb, 0, -1, -1);
142 call_dissector(ip_handle, next_tvb, pinfo, tree);
145 g_assert_not_reached();
149 proto_register_raw(void)
151 static gint *ett[] = {
155 proto_register_subtree_array(ett, array_length(ett));
159 proto_reg_handoff_raw(void)
162 * Get handles for the IP and PPP-in-HDLC-like-framing dissectors.
164 ip_handle = find_dissector("ip");
165 ppp_hdlc_handle = find_dissector("ppp_hdlc");
166 dissector_add("wtap_encap", WTAP_ENCAP_RAW_IP, dissect_raw, -1);