1/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
2#ifndef _UAPI_NF_CONNTRACK_COMMON_H
3#define _UAPI_NF_CONNTRACK_COMMON_H
4/* Connection state tracking for netfilter. This is separated from,
5 but required by, the NAT layer; it can also be used by an iptables
6 extension. */
7enum ip_conntrack_info {
8 /* Part of an established connection (either direction). */
9 IP_CT_ESTABLISHED,
10
11 /* Like NEW, but related to an existing connection, or ICMP error
12 (in either direction). */
13 IP_CT_RELATED,
14
15 /* Started a new connection to track (only
16 IP_CT_DIR_ORIGINAL); may be a retransmission. */
17 IP_CT_NEW,
18
19 /* >= this indicates reply direction */
20 IP_CT_IS_REPLY,
21
22 IP_CT_ESTABLISHED_REPLY = IP_CT_ESTABLISHED + IP_CT_IS_REPLY,
23 IP_CT_RELATED_REPLY = IP_CT_RELATED + IP_CT_IS_REPLY,
24 /* No NEW in reply direction. */
25
26 /* Number of distinct IP_CT types. */
27 IP_CT_NUMBER,
28
29 /* only for userspace compatibility */
30#ifndef __KERNEL__
31 IP_CT_NEW_REPLY = IP_CT_NUMBER,
32#else
33 IP_CT_UNTRACKED = 7,
34#endif
35};
36
37#define NF_CT_STATE_INVALID_BIT (1 << 0)
38#define NF_CT_STATE_BIT(ctinfo) (1 << ((ctinfo) % IP_CT_IS_REPLY + 1))
39#define NF_CT_STATE_UNTRACKED_BIT (1 << 6)
40
41/* Bitset representing status of connection. */
42enum ip_conntrack_status {
43 /* It's an expected connection: bit 0 set. This bit never changed */
44 IPS_EXPECTED_BIT = 0,
45 IPS_EXPECTED = (1 << IPS_EXPECTED_BIT),
46
47 /* We've seen packets both ways: bit 1 set. Can be set, not unset. */
48 IPS_SEEN_REPLY_BIT = 1,
49 IPS_SEEN_REPLY = (1 << IPS_SEEN_REPLY_BIT),
50
51 /* Conntrack should never be early-expired. */
52 IPS_ASSURED_BIT = 2,
53 IPS_ASSURED = (1 << IPS_ASSURED_BIT),
54
55 /* Connection is confirmed: originating packet has left box */
56 IPS_CONFIRMED_BIT = 3,
57 IPS_CONFIRMED = (1 << IPS_CONFIRMED_BIT),
58
59 /* Connection needs src nat in orig dir. This bit never changed. */
60 IPS_SRC_NAT_BIT = 4,
61 IPS_SRC_NAT = (1 << IPS_SRC_NAT_BIT),
62
63 /* Connection needs dst nat in orig dir. This bit never changed. */
64 IPS_DST_NAT_BIT = 5,
65 IPS_DST_NAT = (1 << IPS_DST_NAT_BIT),
66
67 /* Both together. */
68 IPS_NAT_MASK = (IPS_DST_NAT | IPS_SRC_NAT),
69
70 /* Connection needs TCP sequence adjusted. */
71 IPS_SEQ_ADJUST_BIT = 6,
72 IPS_SEQ_ADJUST = (1 << IPS_SEQ_ADJUST_BIT),
73
74 /* NAT initialization bits. */
75 IPS_SRC_NAT_DONE_BIT = 7,
76 IPS_SRC_NAT_DONE = (1 << IPS_SRC_NAT_DONE_BIT),
77
78 IPS_DST_NAT_DONE_BIT = 8,
79 IPS_DST_NAT_DONE = (1 << IPS_DST_NAT_DONE_BIT),
80
81 /* Both together */
82 IPS_NAT_DONE_MASK = (IPS_DST_NAT_DONE | IPS_SRC_NAT_DONE),
83
84 /* Connection is dying (removed from lists), can not be unset. */
85 IPS_DYING_BIT = 9,
86 IPS_DYING = (1 << IPS_DYING_BIT),
87
88 /* Connection has fixed timeout. */
89 IPS_FIXED_TIMEOUT_BIT = 10,
90 IPS_FIXED_TIMEOUT = (1 << IPS_FIXED_TIMEOUT_BIT),
91
92 /* Conntrack is a template */
93 IPS_TEMPLATE_BIT = 11,
94 IPS_TEMPLATE = (1 << IPS_TEMPLATE_BIT),
95
96 /* Conntrack is a fake untracked entry. Obsolete and not used anymore */
97 IPS_UNTRACKED_BIT = 12,
98 IPS_UNTRACKED = (1 << IPS_UNTRACKED_BIT),
99
100#ifdef __KERNEL__
101 /* Re-purposed for in-kernel use:
102 * Tags a conntrack entry that clashed with an existing entry
103 * on insert.
104 */
105 IPS_NAT_CLASH_BIT = IPS_UNTRACKED_BIT,
106 IPS_NAT_CLASH = IPS_UNTRACKED,
107#endif
108
109 /* Conntrack got a helper explicitly attached (ruleset, ctnetlink). */
110 IPS_HELPER_BIT = 13,
111 IPS_HELPER = (1 << IPS_HELPER_BIT),
112
113 /* Conntrack has been offloaded to flow table. */
114 IPS_OFFLOAD_BIT = 14,
115 IPS_OFFLOAD = (1 << IPS_OFFLOAD_BIT),
116
117 /* Conntrack has been offloaded to hardware. */
118 IPS_HW_OFFLOAD_BIT = 15,
119 IPS_HW_OFFLOAD = (1 << IPS_HW_OFFLOAD_BIT),
120
121 /* Be careful here, modifying these bits can make things messy,
122 * so don't let users modify them directly.
123 */
124 IPS_UNCHANGEABLE_MASK = (IPS_NAT_DONE_MASK | IPS_NAT_MASK |
125 IPS_EXPECTED | IPS_CONFIRMED | IPS_DYING |
126 IPS_SEQ_ADJUST | IPS_TEMPLATE | IPS_UNTRACKED |
127 IPS_OFFLOAD | IPS_HW_OFFLOAD),
128
129 __IPS_MAX_BIT = 16,
130};
131
132/* Connection tracking event types */
133enum ip_conntrack_events {
134 IPCT_NEW, /* new conntrack */
135 IPCT_RELATED, /* related conntrack */
136 IPCT_DESTROY, /* destroyed conntrack */
137 IPCT_REPLY, /* connection has seen two-way traffic */
138 IPCT_ASSURED, /* connection status has changed to assured */
139 IPCT_PROTOINFO, /* protocol information has changed */
140 IPCT_HELPER, /* new helper has been set */
141 IPCT_MARK, /* new mark has been set */
142 IPCT_SEQADJ, /* sequence adjustment has changed */
143 IPCT_NATSEQADJ = IPCT_SEQADJ,
144 IPCT_SECMARK, /* new security mark has been set */
145 IPCT_LABEL, /* new connlabel has been set */
146 IPCT_SYNPROXY, /* synproxy has been set */
147#ifdef __KERNEL__
148 __IPCT_MAX
149#endif
150};
151
152enum ip_conntrack_expect_events {
153 IPEXP_NEW, /* new expectation */
154 IPEXP_DESTROY, /* destroyed expectation */
155};
156
157/* expectation flags */
158#define NF_CT_EXPECT_PERMANENT 0x1
159#define NF_CT_EXPECT_INACTIVE 0x2
160#define NF_CT_EXPECT_USERSPACE 0x4
161
162
163#endif /* _UAPI_NF_CONNTRACK_COMMON_H */
164

source code of linux/include/uapi/linux/netfilter/nf_conntrack_common.h