1 /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
2 #ifndef _NFNETLINK_COMPAT_H
3 #define _NFNETLINK_COMPAT_H
4 
5 #include <linux/types.h>
6 
7 #ifndef __KERNEL__
8 /* Old nfnetlink macros for userspace */
9 
10 /* nfnetlink groups: Up to 32 maximum */
11 #define NF_NETLINK_CONNTRACK_NEW 		0x00000001
12 #define NF_NETLINK_CONNTRACK_UPDATE		0x00000002
13 #define NF_NETLINK_CONNTRACK_DESTROY		0x00000004
14 #define NF_NETLINK_CONNTRACK_EXP_NEW		0x00000008
15 #define NF_NETLINK_CONNTRACK_EXP_UPDATE		0x00000010
16 #define NF_NETLINK_CONNTRACK_EXP_DESTROY	0x00000020
17 
18 /* Generic structure for encapsulation optional netfilter information.
19  * It is reminiscent of sockaddr, but with sa_family replaced
20  * with attribute type.
21  * ! This should someday be put somewhere generic as now rtnetlink and
22  * ! nfnetlink use the same attributes methods. - J. Schulist.
23  */
24 
25 struct nfattr {
26 	__u16 nfa_len;
27 	__u16 nfa_type;	/* we use 15 bits for the type, and the highest
28 				 * bit to indicate whether the payload is nested */
29 };
30 
31 /* FIXME: Apart from NFNL_NFA_NESTED shamelessly copy and pasted from
32  * rtnetlink.h, it's time to put this in a generic file */
33 
34 #define NFNL_NFA_NEST	0x8000
35 #define NFA_TYPE(attr) 	((attr)->nfa_type & 0x7fff)
36 
37 #define NFA_ALIGNTO     4
38 #define NFA_ALIGN(len)	(((len) + NFA_ALIGNTO - 1) & ~(NFA_ALIGNTO - 1))
39 #define NFA_OK(nfa,len)	((len) > 0 && (nfa)->nfa_len >= sizeof(struct nfattr) \
40 	&& (nfa)->nfa_len <= (len))
41 #define NFA_NEXT(nfa,attrlen)	((attrlen) -= NFA_ALIGN((nfa)->nfa_len), \
42 	(struct nfattr *)(((char *)(nfa)) + NFA_ALIGN((nfa)->nfa_len)))
43 #define NFA_LENGTH(len)	(NFA_ALIGN(sizeof(struct nfattr)) + (len))
44 #define NFA_SPACE(len)	NFA_ALIGN(NFA_LENGTH(len))
45 #define NFA_DATA(nfa)   ((void *)(((char *)(nfa)) + NFA_LENGTH(0)))
46 #define NFA_PAYLOAD(nfa) ((int)((nfa)->nfa_len) - NFA_LENGTH(0))
47 #define NFA_NEST(skb, type) \
48 ({	struct nfattr *__start = (struct nfattr *)skb_tail_pointer(skb); \
49 	NFA_PUT(skb, (NFNL_NFA_NEST | type), 0, NULL); \
50 	__start;  })
51 #define NFA_NEST_END(skb, start) \
52 ({      (start)->nfa_len = skb_tail_pointer(skb) - (unsigned char *)(start); \
53         (skb)->len; })
54 #define NFA_NEST_CANCEL(skb, start) \
55 ({      if (start) \
56                 skb_trim(skb, (unsigned char *) (start) - (skb)->data); \
57         -1; })
58 
59 #define NFM_NFA(n)      ((struct nfattr *)(((char *)(n)) \
60         + NLMSG_ALIGN(sizeof(struct nfgenmsg))))
61 #define NFM_PAYLOAD(n)  NLMSG_PAYLOAD(n, sizeof(struct nfgenmsg))
62 
63 #endif /* ! __KERNEL__ */
64 #endif /* _NFNETLINK_COMPAT_H */
65