xt_osf.h revision e37d45ce390c2f5a7f1e64742b9100ecef0def54 
1/*
2 * Copyright (c) 2003+ Evgeniy Polyakov <johnpol@2ka.mxt.ru>
3 *
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13 * GNU General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18 */
19
20#ifndef _XT_OSF_H
21#define _XT_OSF_H
22
23#include <linux/types.h>
24
25#define MAXGENRELEN		32
26
27#define XT_OSF_GENRE		(1<<0)
28#define	XT_OSF_TTL		(1<<1)
29#define XT_OSF_LOG		(1<<2)
30#define XT_OSF_INVERT		(1<<3)
31
32#define XT_OSF_LOGLEVEL_ALL	0	/* log all matched fingerprints */
33#define XT_OSF_LOGLEVEL_FIRST	1	/* log only the first matced fingerprint */
34#define XT_OSF_LOGLEVEL_ALL_KNOWN	2 /* do not log unknown packets */
35
36#define XT_OSF_TTL_TRUE		0	/* True ip and fingerprint TTL comparison */
37#define XT_OSF_TTL_LESS		1	/* Check if ip TTL is less than fingerprint one */
38#define XT_OSF_TTL_NOCHECK	2	/* Do not compare ip and fingerprint TTL at all */
39
40struct xt_osf_info {
41	char			genre[MAXGENRELEN];
42	__u32			len;
43	__u32			flags;
44	__u32			loglevel;
45	__u32			ttl;
46};
47
48/*
49 * Wildcard MSS (kind of).
50 * It is used to implement a state machine for the different wildcard values
51 * of the MSS and window sizes.
52 */
53struct xt_osf_wc {
54	__u32			wc;
55	__u32			val;
56};
57
58/*
59 * This struct represents IANA options
60 * http://www.iana.org/assignments/tcp-parameters
61 */
62struct xt_osf_opt {
63	__u16			kind, length;
64	struct xt_osf_wc	wc;
65};
66
67struct xt_osf_user_finger {
68	struct xt_osf_wc	wss;
69
70	__u8			ttl, df;
71	__u16			ss, mss;
72	__u16			opt_num;
73
74	char			genre[MAXGENRELEN];
75	char			version[MAXGENRELEN];
76	char			subtype[MAXGENRELEN];
77
78	/* MAX_IPOPTLEN is maximum if all options are NOPs or EOLs */
79	struct xt_osf_opt	opt[MAX_IPOPTLEN];
80};
81
82struct xt_osf_nlmsg {
83	struct xt_osf_user_finger	f;
84	struct iphdr		ip;
85	struct tcphdr		tcp;
86};
87
88/* Defines for IANA option kinds */
89
90enum iana_options {
91	OSFOPT_EOL = 0,		/* End of options */
92	OSFOPT_NOP, 		/* NOP */
93	OSFOPT_MSS, 		/* Maximum segment size */
94	OSFOPT_WSO, 		/* Window scale option */
95	OSFOPT_SACKP,		/* SACK permitted */
96	OSFOPT_SACK,		/* SACK */
97	OSFOPT_ECHO,
98	OSFOPT_ECHOREPLY,
99	OSFOPT_TS,		/* Timestamp option */
100	OSFOPT_POCP,		/* Partial Order Connection Permitted */
101	OSFOPT_POSP,		/* Partial Order Service Profile */
102
103	/* Others are not used in the current OSF */
104	OSFOPT_EMPTY = 255,
105};
106
107/*
108 * Initial window size option state machine: multiple of mss, mtu or
109 * plain numeric value. Can also be made as plain numeric value which
110 * is not a multiple of specified value.
111 */
112enum xt_osf_window_size_options {
113	OSF_WSS_PLAIN	= 0,
114	OSF_WSS_MSS,
115	OSF_WSS_MTU,
116	OSF_WSS_MODULO,
117	OSF_WSS_MAX,
118};
119
120/*
121 * Add/remove fingerprint from the kernel.
122 */
123enum xt_osf_msg_types {
124	OSF_MSG_ADD,
125	OSF_MSG_REMOVE,
126	OSF_MSG_MAX,
127};
128
129enum xt_osf_attr_type {
130	OSF_ATTR_UNSPEC,
131	OSF_ATTR_FINGER,
132	OSF_ATTR_MAX,
133};
134
135#endif				/* _XT_OSF_H */
136