1 #ifndef _NF_OSF_H
2 #define _NF_OSF_H
3 
4 #include <linux/types.h>
5 #include <linux/ip.h>
6 #include <linux/tcp.h>
7 
8 #define MAXGENRELEN	32
9 
10 #define NF_OSF_GENRE	(1 << 0)
11 #define NF_OSF_TTL	(1 << 1)
12 #define NF_OSF_LOG	(1 << 2)
13 #define NF_OSF_INVERT	(1 << 3)
14 
15 #define NF_OSF_LOGLEVEL_ALL		0	/* log all matched fingerprints */
16 #define NF_OSF_LOGLEVEL_FIRST		1	/* log only the first matced fingerprint */
17 #define NF_OSF_LOGLEVEL_ALL_KNOWN	2	/* do not log unknown packets */
18 
19 #define NF_OSF_TTL_TRUE			0	/* True ip and fingerprint TTL comparison */
20 
21 /* Check if ip TTL is less than fingerprint one */
22 #define NF_OSF_TTL_LESS			1
23 
24 /* Do not compare ip and fingerprint TTL at all */
25 #define NF_OSF_TTL_NOCHECK		2
26 
27 #define NF_OSF_FLAGMASK		(NF_OSF_GENRE | NF_OSF_TTL | \
28 				 NF_OSF_LOG | NF_OSF_INVERT)
29 /* Wildcard MSS (kind of).
30  * It is used to implement a state machine for the different wildcard values
31  * of the MSS and window sizes.
32  */
33 struct nf_osf_wc {
34 	__u32	wc;
35 	__u32	val;
36 };
37 
38 /* This struct represents IANA options
39  * http://www.iana.org/assignments/tcp-parameters
40  */
41 struct nf_osf_opt {
42 	__u16			kind, length;
43 	struct nf_osf_wc	wc;
44 };
45 
46 struct nf_osf_info {
47 	char	genre[MAXGENRELEN];
48 	__u32	len;
49 	__u32	flags;
50 	__u32	loglevel;
51 	__u32	ttl;
52 };
53 
54 struct nf_osf_user_finger {
55 	struct nf_osf_wc	wss;
56 
57 	__u8	ttl, df;
58 	__u16	ss, mss;
59 	__u16	opt_num;
60 
61 	char	genre[MAXGENRELEN];
62 	char	version[MAXGENRELEN];
63 	char	subtype[MAXGENRELEN];
64 
65 	/* MAX_IPOPTLEN is maximum if all options are NOPs or EOLs */
66 	struct nf_osf_opt	opt[MAX_IPOPTLEN];
67 };
68 
69 struct nf_osf_nlmsg {
70 	struct nf_osf_user_finger	f;
71 	struct iphdr			ip;
72 	struct tcphdr			tcp;
73 };
74 
75 /* Defines for IANA option kinds */
76 enum iana_options {
77 	OSFOPT_EOL = 0,		/* End of options */
78 	OSFOPT_NOP,		/* NOP */
79 	OSFOPT_MSS,		/* Maximum segment size */
80 	OSFOPT_WSO,		/* Window scale option */
81 	OSFOPT_SACKP,		/* SACK permitted */
82 	OSFOPT_SACK,		/* SACK */
83 	OSFOPT_ECHO,
84 	OSFOPT_ECHOREPLY,
85 	OSFOPT_TS,		/* Timestamp option */
86 	OSFOPT_POCP,		/* Partial Order Connection Permitted */
87 	OSFOPT_POSP,		/* Partial Order Service Profile */
88 
89 	/* Others are not used in the current OSF */
90 	OSFOPT_EMPTY = 255,
91 };
92 
93 /* Initial window size option state machine: multiple of mss, mtu or
94  * plain numeric value. Can also be made as plain numeric value which
95  * is not a multiple of specified value.
96  */
97 enum nf_osf_window_size_options {
98 	OSF_WSS_PLAIN	= 0,
99 	OSF_WSS_MSS,
100 	OSF_WSS_MTU,
101 	OSF_WSS_MODULO,
102 	OSF_WSS_MAX,
103 };
104 
105 enum nf_osf_attr_type {
106 	OSF_ATTR_UNSPEC,
107 	OSF_ATTR_FINGER,
108 	OSF_ATTR_MAX,
109 };
110 
111 /*
112  * Add/remove fingerprint from the kernel.
113  */
114 enum nf_osf_msg_types {
115 	OSF_MSG_ADD,
116 	OSF_MSG_REMOVE,
117 	OSF_MSG_MAX,
118 };
119 
120 #endif /* _NF_OSF_H */
121