1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * connection tracking event cache.
4 */
5
6#ifndef _NF_CONNTRACK_ECACHE_H
7#define _NF_CONNTRACK_ECACHE_H
8#include <net/netfilter/nf_conntrack.h>
9
10#include <net/net_namespace.h>
11#include <net/netfilter/nf_conntrack_expect.h>
12#include <linux/netfilter/nf_conntrack_common.h>
13#include <linux/netfilter/nf_conntrack_tuple_common.h>
14#include <net/netfilter/nf_conntrack_extend.h>
15
16enum nf_ct_ecache_state {
17	NFCT_ECACHE_DESTROY_FAIL,	/* tried but failed to send destroy event */
18	NFCT_ECACHE_DESTROY_SENT,	/* sent destroy event after failure */
19};
20
21struct nf_conntrack_ecache {
22	unsigned long cache;		/* bitops want long */
23	u16 ctmask;			/* bitmask of ct events to be delivered */
24	u16 expmask;			/* bitmask of expect events to be delivered */
25	u32 missed;			/* missed events */
26	u32 portid;			/* netlink portid of destroyer */
27};
28
29static inline struct nf_conntrack_ecache *
30nf_ct_ecache_find(const struct nf_conn *ct)
31{
32#ifdef CONFIG_NF_CONNTRACK_EVENTS
33	return nf_ct_ext_find(ct, NF_CT_EXT_ECACHE);
34#else
35	return NULL;
36#endif
37}
38
39static inline bool nf_ct_ecache_exist(const struct nf_conn *ct)
40{
41#ifdef CONFIG_NF_CONNTRACK_EVENTS
42	return nf_ct_ext_exist(ct, NF_CT_EXT_ECACHE);
43#else
44	return false;
45#endif
46}
47
48#ifdef CONFIG_NF_CONNTRACK_EVENTS
49
50/* This structure is passed to event handler */
51struct nf_ct_event {
52	struct nf_conn *ct;
53	u32 portid;
54	int report;
55};
56
57struct nf_exp_event {
58	struct nf_conntrack_expect *exp;
59	u32 portid;
60	int report;
61};
62
63struct nf_ct_event_notifier {
64	int (*ct_event)(unsigned int events, const struct nf_ct_event *item);
65	int (*exp_event)(unsigned int events, const struct nf_exp_event *item);
66};
67
68void nf_conntrack_register_notifier(struct net *net,
69				   const struct nf_ct_event_notifier *nb);
70void nf_conntrack_unregister_notifier(struct net *net);
71
72void nf_ct_deliver_cached_events(struct nf_conn *ct);
73int nf_conntrack_eventmask_report(unsigned int eventmask, struct nf_conn *ct,
74				  u32 portid, int report);
75
76bool nf_ct_ecache_ext_add(struct nf_conn *ct, u16 ctmask, u16 expmask, gfp_t gfp);
77#else
78
79static inline void nf_ct_deliver_cached_events(const struct nf_conn *ct)
80{
81}
82
83static inline int nf_conntrack_eventmask_report(unsigned int eventmask,
84						struct nf_conn *ct,
85						u32 portid,
86						int report)
87{
88	return 0;
89}
90
91static inline bool nf_ct_ecache_ext_add(struct nf_conn *ct, u16 ctmask, u16 expmask, gfp_t gfp)
92{
93	return false;
94}
95#endif
96
97static inline void
98nf_conntrack_event_cache(enum ip_conntrack_events event, struct nf_conn *ct)
99{
100#ifdef CONFIG_NF_CONNTRACK_EVENTS
101	struct net *net = nf_ct_net(ct);
102	struct nf_conntrack_ecache *e;
103
104	if (!rcu_access_pointer(net->ct.nf_conntrack_event_cb))
105		return;
106
107	e = nf_ct_ecache_find(ct);
108	if (e == NULL)
109		return;
110
111	set_bit(event, &e->cache);
112#endif
113}
114
115static inline int
116nf_conntrack_event_report(enum ip_conntrack_events event, struct nf_conn *ct,
117			  u32 portid, int report)
118{
119#ifdef CONFIG_NF_CONNTRACK_EVENTS
120	if (nf_ct_ecache_exist(ct))
121		return nf_conntrack_eventmask_report(1 << event, ct, portid, report);
122#endif
123	return 0;
124}
125
126static inline int
127nf_conntrack_event(enum ip_conntrack_events event, struct nf_conn *ct)
128{
129#ifdef CONFIG_NF_CONNTRACK_EVENTS
130	if (nf_ct_ecache_exist(ct))
131		return nf_conntrack_eventmask_report(1 << event, ct, 0, 0);
132#endif
133	return 0;
134}
135
136#ifdef CONFIG_NF_CONNTRACK_EVENTS
137void nf_ct_expect_event_report(enum ip_conntrack_expect_events event,
138			       struct nf_conntrack_expect *exp,
139			       u32 portid, int report);
140
141void nf_conntrack_ecache_work(struct net *net, enum nf_ct_ecache_state state);
142
143void nf_conntrack_ecache_pernet_init(struct net *net);
144void nf_conntrack_ecache_pernet_fini(struct net *net);
145
146struct nf_conntrack_net_ecache *nf_conn_pernet_ecache(const struct net *net);
147
148static inline bool nf_conntrack_ecache_dwork_pending(const struct net *net)
149{
150	return net->ct.ecache_dwork_pending;
151}
152#else /* CONFIG_NF_CONNTRACK_EVENTS */
153
154static inline void nf_ct_expect_event_report(enum ip_conntrack_expect_events e,
155					     struct nf_conntrack_expect *exp,
156					     u32 portid,
157					     int report)
158{
159}
160
161static inline void nf_conntrack_ecache_work(struct net *net,
162					    enum nf_ct_ecache_state s)
163{
164}
165
166static inline void nf_conntrack_ecache_pernet_init(struct net *net)
167{
168}
169
170static inline void nf_conntrack_ecache_pernet_fini(struct net *net)
171{
172}
173static inline bool nf_conntrack_ecache_dwork_pending(const struct net *net) { return false; }
174#endif /* CONFIG_NF_CONNTRACK_EVENTS */
175#endif /*_NF_CONNTRACK_ECACHE_H*/
176