xref: /linux/include/uapi/linux/netfilter.h (revision 4f2c0a4acffbec01079c28f839422e64ddeff004)
1 /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
2 #ifndef _UAPI__LINUX_NETFILTER_H
3 #define _UAPI__LINUX_NETFILTER_H
4 
5 #include <linux/types.h>
6 #include <linux/compiler.h>
7 #include <linux/in.h>
8 #include <linux/in6.h>
9 
10 /* Responses from hook functions. */
11 #define NF_DROP 0
12 #define NF_ACCEPT 1
13 #define NF_STOLEN 2
14 #define NF_QUEUE 3
15 #define NF_REPEAT 4
16 #define NF_STOP 5	/* Deprecated, for userspace nf_queue compatibility. */
17 #define NF_MAX_VERDICT NF_STOP
18 
19 /* we overload the higher bits for encoding auxiliary data such as the queue
20  * number or errno values. Not nice, but better than additional function
21  * arguments. */
22 #define NF_VERDICT_MASK 0x000000ff
23 
24 /* extra verdict flags have mask 0x0000ff00 */
25 #define NF_VERDICT_FLAG_QUEUE_BYPASS	0x00008000
26 
27 /* queue number (NF_QUEUE) or errno (NF_DROP) */
28 #define NF_VERDICT_QMASK 0xffff0000
29 #define NF_VERDICT_QBITS 16
30 
31 #define NF_QUEUE_NR(x) ((((x) << 16) & NF_VERDICT_QMASK) | NF_QUEUE)
32 
33 #define NF_DROP_ERR(x) (((-x) << 16) | NF_DROP)
34 
35 /* only for userspace compatibility */
36 #ifndef __KERNEL__
37 
38 /* NF_VERDICT_BITS should be 8 now, but userspace might break if this changes */
39 #define NF_VERDICT_BITS 16
40 #endif
41 
42 enum nf_inet_hooks {
43 	NF_INET_PRE_ROUTING,
44 	NF_INET_LOCAL_IN,
45 	NF_INET_FORWARD,
46 	NF_INET_LOCAL_OUT,
47 	NF_INET_POST_ROUTING,
48 	NF_INET_NUMHOOKS,
49 	NF_INET_INGRESS = NF_INET_NUMHOOKS,
50 };
51 
52 enum nf_dev_hooks {
53 	NF_NETDEV_INGRESS,
54 	NF_NETDEV_EGRESS,
55 	NF_NETDEV_NUMHOOKS
56 };
57 
58 enum {
59 	NFPROTO_UNSPEC =  0,
60 	NFPROTO_INET   =  1,
61 	NFPROTO_IPV4   =  2,
62 	NFPROTO_ARP    =  3,
63 	NFPROTO_NETDEV =  5,
64 	NFPROTO_BRIDGE =  7,
65 	NFPROTO_IPV6   = 10,
66 #ifndef __KERNEL__ /* no longer supported by kernel */
67 	NFPROTO_DECNET = 12,
68 #endif
69 	NFPROTO_NUMPROTO,
70 };
71 
72 union nf_inet_addr {
73 	__u32		all[4];
74 	__be32		ip;
75 	__be32		ip6[4];
76 	struct in_addr	in;
77 	struct in6_addr	in6;
78 };
79 
80 #endif /* _UAPI__LINUX_NETFILTER_H */
81