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
|
#ifndef _NFNETLINK_H
#define _NFNETLINK_H
#include <linux/types.h>
/* nfnetlink groups: Up to 32 maximum */
#define NF_NETLINK_CONNTRACK_NEW 0x00000001
#define NF_NETLINK_CONNTRACK_UPDATE 0x00000002
#define NF_NETLINK_CONNTRACK_DESTROY 0x00000004
#define NF_NETLINK_CONNTRACK_EXP_NEW 0x00000008
#define NF_NETLINK_CONNTRACK_EXP_UPDATE 0x00000010
#define NF_NETLINK_CONNTRACK_EXP_DESTROY 0x00000020
/* Generic structure for encapsulation optional netfilter information.
* It is reminiscent of sockaddr, but with sa_family replaced
* with attribute type.
* ! This should someday be put somewhere generic as now rtnetlink and
* ! nfnetlink use the same attributes methods. - J. Schulist.
*/
struct nfattr
{
u_int16_t nfa_len;
u_int16_t nfa_type;
} __attribute__ ((packed));
/* FIXME: Shamelessly copy and pasted from rtnetlink.h, it's time
* to put this in a generic file */
#define NFA_ALIGNTO 4
#define NFA_ALIGN(len) (((len) + NFA_ALIGNTO - 1) & ~(NFA_ALIGNTO - 1))
#define NFA_OK(nfa,len) ((len) > 0 && (nfa)->nfa_len >= sizeof(struct nfattr) \
&& (nfa)->nfa_len <= (len))
#define NFA_NEXT(nfa,attrlen) ((attrlen) -= NFA_ALIGN((nfa)->nfa_len), \
(struct nfattr *)(((char *)(nfa)) + NFA_ALIGN((nfa)->nfa_len)))
#define NFA_LENGTH(len) (NFA_ALIGN(sizeof(struct nfattr)) + (len))
#define NFA_SPACE(len) NFA_ALIGN(NFA_LENGTH(len))
#define NFA_DATA(nfa) ((void *)(((char *)(nfa)) + NFA_LENGTH(0)))
#define NFA_PAYLOAD(nfa) ((int)((nfa)->nfa_len) - NFA_LENGTH(0))
#define NFA_NEST(skb, type) \
({ struct nfattr *__start = (struct nfattr *) (skb)->tail; \
NFA_PUT(skb, type, 0, NULL); \
__start; })
#define NFA_NEST_END(skb, start) \
({ (start)->nfa_len = ((skb)->tail - (unsigned char *) (start)); \
(skb)->len; })
#define NFA_NEST_CANCEL(skb, start) \
({ if (start) \
skb_trim(skb, (unsigned char *) (start) - (skb)->data); \
-1; })
/* General form of address family dependent message.
*/
struct nfgenmsg {
u_int8_t nfgen_family; /* AF_xxx */
u_int8_t version; /* nfnetlink version */
u_int16_t res_id; /* resource id */
} __attribute__ ((packed));
#define NFNETLINK_V0 0
#define NFM_NFA(n) ((struct nfattr *)(((char *)(n)) \
+ NLMSG_ALIGN(sizeof(struct nfgenmsg))))
#define NFM_PAYLOAD(n) NLMSG_PAYLOAD(n, sizeof(struct nfgenmsg))
/* netfilter netlink message types are split in two pieces:
* 8 bit subsystem, 8bit operation.
*/
#define NFNL_SUBSYS_ID(x) ((x & 0xff00) >> 8)
#define NFNL_MSG_TYPE(x) (x & 0x00ff)
enum nfnl_subsys_id {
NFNL_SUBSYS_NONE = 0,
NFNL_SUBSYS_CTNETLINK,
NFNL_SUBSYS_CTNETLINK_EXP,
NFNL_SUBSYS_IPTNETLINK,
NFNL_SUBSYS_QUEUE,
NFNL_SUBSYS_ULOG,
NFNL_SUBSYS_COUNT,
};
#ifdef __KERNEL__
#include <linux/netlink.h>
#include <linux/capability.h>
struct nfnl_callback
{
kernel_cap_t cap_required; /* capabilities required for this msg */
int (*call)(struct sock *nl, struct sk_buff *skb,
struct nlmsghdr *nlh, struct nfattr *cda[], int *errp);
};
struct nfnetlink_subsystem
{
const char *name;
__u8 subsys_id; /* nfnetlink subsystem ID */
__u8 cb_count; /* number of callbacks */
u_int32_t attr_count; /* number of nfattr's */
struct nfnl_callback *cb; /* callback for individual types */
};
extern void __nfa_fill(struct sk_buff *skb, int attrtype,
int attrlen, const void *data);
#define NFA_PUT(skb, attrtype, attrlen, data) \
({ if (skb_tailroom(skb) < (int)NFA_SPACE(attrlen)) goto nfattr_failure; \
__nfa_fill(skb, attrtype, attrlen, data); })
extern struct semaphore nfnl_sem;
#define nfnl_shlock() down(&nfnl_sem)
#define nfnl_shlock_nowait() down_trylock(&nfnl_sem)
#define nfnl_shunlock() do { up(&nfnl_sem); \
if(nfnl && nfnl->sk_receive_queue.qlen) \
nfnl->sk_data_ready(nfnl, 0); \
} while(0)
extern void nfnl_lock(void);
extern void nfnl_unlock(void);
extern int nfnetlink_subsys_register(struct nfnetlink_subsystem *n);
extern int nfnetlink_subsys_unregister(struct nfnetlink_subsystem *n);
extern int nfattr_parse(struct nfattr *tb[], int maxattr,
struct nfattr *nfa, int len);
#define nfattr_parse_nested(tb, max, nfa) \
nfattr_parse((tb), (max), NFA_DATA((nfa)), NFA_PAYLOAD((nfa)))
#define nfattr_bad_size(tb, max, cta_min) \
({ int __i, __res = 0; \
for (__i=0; __i<max; __i++) \
if (tb[__i] && NFA_PAYLOAD(tb[__i]) < cta_min[__i]){ \
__res = 1; \
break; \
} \
__res; \
})
extern int nfnetlink_send(struct sk_buff *skb, u32 pid, unsigned group,
int echo);
extern int nfnetlink_unicast(struct sk_buff *skb, u_int32_t pid, int flags);
#endif /* __KERNEL__ */
#endif /* _NFNETLINK_H */
|