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
|
/* packet-pflog.c
* Routines for pflog (OpenBSD Firewall Logging) packet disassembly
*
* $Id: packet-pflog.c,v 1.5 2002/07/15 20:55:51 guy Exp $
*
* Copyright 2001 Mike Frantzen
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#ifdef HAVE_SYS_TYPES_H
# include <sys/types.h>
#endif
#include <string.h>
#include <glib.h>
#include <epan/packet.h>
#include "etypes.h"
#include <epan/resolv.h>
#include "packet-ip.h"
#include "packet-ipv6.h"
#include "packet-pflog.h"
#ifndef offsetof
/* Can't trust stddef.h to be there for us */
# define offsetof(type, member) ((size_t)(&((type *)0)->member))
#endif
static dissector_handle_t data_handle, ip_handle, ipv6_handle;
/* header fields */
static int proto_pflog = -1;
static int hf_pflog_af = -1;
static int hf_pflog_ifname = -1;
static int hf_pflog_rnr = -1;
static int hf_pflog_reason = -1;
static int hf_pflog_action = -1;
static int hf_pflog_dir = -1;
static gint ett_pflog = -1;
void
capture_pflog(const u_char *pd, int offset, int len, packet_counts *ld)
{
struct pfloghdr pflogh;
if (!BYTES_ARE_IN_FRAME(offset, len, (int)PFLOG_HDRLEN)) {
ld->other++;
return;
}
offset += PFLOG_HDRLEN;
/* Copy out the pflog header to insure alignment */
memcpy(&pflogh, pd, sizeof(pflogh));
pflogh.af = g_ntohl(pflogh.af);
switch (pflogh.af) {
case BSD_PF_INET:
capture_ip(pd, offset, len, ld);
break;
#ifdef notyet
case BSD_PF_INET6:
capture_ipv6(pd, offset, len, ld);
break;
#endif
default:
ld->other++;
break;
}
}
static const value_string af_vals[] = {
{ BSD_PF_INET, "IPv4" },
{ BSD_PF_INET6, "IPv6" },
{ 0, NULL }
};
static const value_string reason_vals[] = {
{ 0, "match" },
{ 1, "bad-offset" },
{ 2, "fragment" },
{ 3, "short" },
{ 4, "normalize" },
{ 5, "memory" },
{ 0, NULL }
};
static const value_string action_vals[] = {
{ PF_PASS, "passed" },
{ PF_DROP, "dropped" },
{ PF_SCRUB, "scrubbed" },
{ 0, NULL }
};
static const value_string dir_vals[] = {
{ PF_IN, "in" },
{ PF_OUT, "out" },
{ 0, NULL }
};
static void
dissect_pflog(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
{
struct pfloghdr pflogh;
tvbuff_t *next_tvb;
proto_tree *pflog_tree;
proto_item *ti;
if (check_col(pinfo->cinfo, COL_PROTOCOL))
col_set_str(pinfo->cinfo, COL_PROTOCOL, "PFLOG");
/* Copy out the pflog header to insure alignment */
tvb_memcpy(tvb, (guint8 *)&pflogh, 0, sizeof(pflogh));
/* Byteswap the header now */
pflogh.af = g_ntohl(pflogh.af);
pflogh.rnr = g_ntohs(pflogh.rnr);
pflogh.reason = g_ntohs(pflogh.reason);
pflogh.action = g_ntohs(pflogh.action);
pflogh.dir = g_ntohs(pflogh.dir);
if (tree) {
ti = proto_tree_add_protocol_format(tree, proto_pflog, tvb, 0,
PFLOG_HDRLEN,
"PF Log %s %s on %s by rule %d",
val_to_str(pflogh.af, af_vals, "unknown (%u)"),
val_to_str(pflogh.action, action_vals, "unknown (%u)"),
pflogh.ifname,
pflogh.rnr);
pflog_tree = proto_item_add_subtree(ti, ett_pflog);
proto_tree_add_uint(pflog_tree, hf_pflog_af, tvb,
offsetof(struct pfloghdr, af), sizeof(pflogh.af),
pflogh.af);
proto_tree_add_int(pflog_tree, hf_pflog_rnr, tvb,
offsetof(struct pfloghdr, rnr), sizeof(pflogh.rnr),
pflogh.rnr);
proto_tree_add_string(pflog_tree, hf_pflog_ifname, tvb,
offsetof(struct pfloghdr, ifname), sizeof(pflogh.ifname),
pflogh.ifname);
proto_tree_add_uint(pflog_tree, hf_pflog_reason, tvb,
offsetof(struct pfloghdr, reason), sizeof(pflogh.reason),
pflogh.reason);
proto_tree_add_uint(pflog_tree, hf_pflog_action, tvb,
offsetof(struct pfloghdr, action), sizeof(pflogh.action),
pflogh.action);
proto_tree_add_uint(pflog_tree, hf_pflog_dir, tvb,
offsetof(struct pfloghdr, dir), sizeof(pflogh.dir),
pflogh.dir);
}
/* Set the tvbuff for the payload after the header */
next_tvb = tvb_new_subset(tvb, PFLOG_HDRLEN, -1, -1);
switch (pflogh.af) {
case BSD_PF_INET:
call_dissector(ip_handle, next_tvb, pinfo, tree);
break;
case BSD_PF_INET6:
call_dissector(ipv6_handle, next_tvb, pinfo, tree);
break;
default:
call_dissector(data_handle, next_tvb, pinfo, tree);
break;
}
if (check_col(pinfo->cinfo, COL_INFO)) {
col_prepend_fstr(pinfo->cinfo, COL_INFO, "[%s %s/#%d] ",
val_to_str(pflogh.action, action_vals, "unknown (%u)"),
pflogh.ifname,
pflogh.rnr);
}
}
void
proto_register_pflog(void)
{
static hf_register_info hf[] = {
{ &hf_pflog_af,
{ "Address Family", "pflog.af", FT_UINT32, BASE_DEC, VALS(af_vals), 0x0,
"Protocol (IPv4 vs IPv6)", HFILL }},
{ &hf_pflog_ifname,
{ "Interface", "pflog.ifname", FT_STRING, BASE_NONE, NULL, 0x0,
"Interface", HFILL }},
{ &hf_pflog_rnr,
{ "Rule Number", "pflog.rnr", FT_INT16, BASE_DEC, NULL, 0x0,
"Last matched firewall rule number", HFILL }},
{ &hf_pflog_reason,
{ "Reason", "pflog.reason", FT_UINT16, BASE_DEC, VALS(reason_vals), 0x0,
"Reason for logging the packet", HFILL }},
{ &hf_pflog_action,
{ "Action", "pflog.action", FT_UINT16, BASE_DEC, VALS(action_vals), 0x0,
"Action taken by PF on the packet", HFILL }},
{ &hf_pflog_dir,
{ "Direction", "pflog.dir", FT_UINT16, BASE_DEC, VALS(dir_vals), 0x0,
"Direction of packet in stack (inbound versus outbound)", HFILL }},
};
static gint *ett[] = { &ett_pflog };
proto_pflog = proto_register_protocol("OpenBSD Packet Filter log file",
"PFLOG", "pflog");
proto_register_field_array(proto_pflog, hf, array_length(hf));
proto_register_subtree_array(ett, array_length(ett));
}
void
proto_reg_handoff_pflog(void)
{
dissector_handle_t pflog_handle;
ip_handle = find_dissector("ip");
ipv6_handle = find_dissector("ipv6");
data_handle = find_dissector("data");
pflog_handle = create_dissector_handle(dissect_pflog, proto_pflog);
dissector_add("wtap_encap", WTAP_ENCAP_PFLOG, pflog_handle);
}
|
