nfnetlink_compat.h

 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
25struct 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 */