xref: /linux-6.15/include/linux/netfilter_ipv4.h (revision 93c06cbb)
1 #ifndef __LINUX_IP_NETFILTER_H
2 #define __LINUX_IP_NETFILTER_H
3 
4 /* IPv4-specific defines for netfilter.
5  * (C)1998 Rusty Russell -- This code is GPL.
6  */
7 
8 #include <linux/netfilter.h>
9 
10 /* only for userspace compatibility */
11 #ifndef __KERNEL__
12 /* IP Cache bits. */
13 /* Src IP address. */
14 #define NFC_IP_SRC		0x0001
15 /* Dest IP address. */
16 #define NFC_IP_DST		0x0002
17 /* Input device. */
18 #define NFC_IP_IF_IN		0x0004
19 /* Output device. */
20 #define NFC_IP_IF_OUT		0x0008
21 /* TOS. */
22 #define NFC_IP_TOS		0x0010
23 /* Protocol. */
24 #define NFC_IP_PROTO		0x0020
25 /* IP options. */
26 #define NFC_IP_OPTIONS		0x0040
27 /* Frag & flags. */
28 #define NFC_IP_FRAG		0x0080
29 
30 /* Per-protocol information: only matters if proto match. */
31 /* TCP flags. */
32 #define NFC_IP_TCPFLAGS		0x0100
33 /* Source port. */
34 #define NFC_IP_SRC_PT		0x0200
35 /* Dest port. */
36 #define NFC_IP_DST_PT		0x0400
37 /* Something else about the proto */
38 #define NFC_IP_PROTO_UNKNOWN	0x2000
39 
40 /* IP Hooks */
41 /* After promisc drops, checksum checks. */
42 #define NF_IP_PRE_ROUTING	0
43 /* If the packet is destined for this box. */
44 #define NF_IP_LOCAL_IN		1
45 /* If the packet is destined for another interface. */
46 #define NF_IP_FORWARD		2
47 /* Packets coming from a local process. */
48 #define NF_IP_LOCAL_OUT		3
49 /* Packets about to hit the wire. */
50 #define NF_IP_POST_ROUTING	4
51 #define NF_IP_NUMHOOKS		5
52 #endif /* ! __KERNEL__ */
53 
54 enum nf_ip_hook_priorities {
55 	NF_IP_PRI_FIRST = INT_MIN,
56 	NF_IP_PRI_CONNTRACK_DEFRAG = -400,
57 	NF_IP_PRI_RAW = -300,
58 	NF_IP_PRI_SELINUX_FIRST = -225,
59 	NF_IP_PRI_CONNTRACK = -200,
60 	NF_IP_PRI_MANGLE = -150,
61 	NF_IP_PRI_NAT_DST = -100,
62 	NF_IP_PRI_FILTER = 0,
63 	NF_IP_PRI_SECURITY = 50,
64 	NF_IP_PRI_NAT_SRC = 100,
65 	NF_IP_PRI_SELINUX_LAST = 225,
66 	NF_IP_PRI_CONNTRACK_CONFIRM = INT_MAX,
67 	NF_IP_PRI_LAST = INT_MAX,
68 };
69 
70 /* Arguments for setsockopt SOL_IP: */
71 /* 2.0 firewalling went from 64 through 71 (and +256, +512, etc). */
72 /* 2.2 firewalling (+ masq) went from 64 through 76 */
73 /* 2.4 firewalling went 64 through 67. */
74 #define SO_ORIGINAL_DST 80
75 
76 #ifdef __KERNEL__
77 extern int ip_route_me_harder(struct sk_buff *skb, unsigned addr_type);
78 extern int ip_xfrm_me_harder(struct sk_buff *skb);
79 extern __sum16 nf_ip_checksum(struct sk_buff *skb, unsigned int hook,
80 				   unsigned int dataoff, u_int8_t protocol);
81 #endif /*__KERNEL__*/
82 
83 #endif /*__LINUX_IP_NETFILTER_H*/
84