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
16 enum nf_ct_ecache_state {
17 NFCT_ECACHE_UNKNOWN, /* destroy event not sent */
18 NFCT_ECACHE_DESTROY_FAIL, /* tried but failed to send destroy event */
19 NFCT_ECACHE_DESTROY_SENT, /* sent destroy event after failure */
20 };
21
22 struct nf_conntrack_ecache {
23 unsigned long cache; /* bitops want long */
24 u16 missed; /* missed events */
25 u16 ctmask; /* bitmask of ct events to be delivered */
26 u16 expmask; /* bitmask of expect events to be delivered */
27 enum nf_ct_ecache_state state:8;/* ecache state */
28 u32 portid; /* netlink portid of destroyer */
29 };
30
31 static inline struct nf_conntrack_ecache *
nf_ct_ecache_find(const struct nf_conn * ct)32 nf_ct_ecache_find(const struct nf_conn *ct)
33 {
34 #ifdef CONFIG_NF_CONNTRACK_EVENTS
35 return nf_ct_ext_find(ct, NF_CT_EXT_ECACHE);
36 #else
37 return NULL;
38 #endif
39 }
40
41 static inline struct nf_conntrack_ecache *
nf_ct_ecache_ext_add(struct nf_conn * ct,u16 ctmask,u16 expmask,gfp_t gfp)42 nf_ct_ecache_ext_add(struct nf_conn *ct, u16 ctmask, u16 expmask, gfp_t gfp)
43 {
44 #ifdef CONFIG_NF_CONNTRACK_EVENTS
45 struct net *net = nf_ct_net(ct);
46 struct nf_conntrack_ecache *e;
47
48 if (!ctmask && !expmask && net->ct.sysctl_events) {
49 ctmask = ~0;
50 expmask = ~0;
51 }
52 if (!ctmask && !expmask)
53 return NULL;
54
55 e = nf_ct_ext_add(ct, NF_CT_EXT_ECACHE, gfp);
56 if (e) {
57 e->ctmask = ctmask;
58 e->expmask = expmask;
59 }
60 return e;
61 #else
62 return NULL;
63 #endif
64 }
65
66 #ifdef CONFIG_NF_CONNTRACK_EVENTS
67
68 /* This structure is passed to event handler */
69 struct nf_ct_event {
70 struct nf_conn *ct;
71 u32 portid;
72 int report;
73 };
74
75 struct nf_ct_event_notifier {
76 int (*fcn)(unsigned int events, struct nf_ct_event *item);
77 };
78
79 int nf_conntrack_register_notifier(struct net *net,
80 struct nf_ct_event_notifier *nb);
81 void nf_conntrack_unregister_notifier(struct net *net,
82 struct nf_ct_event_notifier *nb);
83
84 void nf_ct_deliver_cached_events(struct nf_conn *ct);
85 int nf_conntrack_eventmask_report(unsigned int eventmask, struct nf_conn *ct,
86 u32 portid, int report);
87
88 #else
89
nf_ct_deliver_cached_events(const struct nf_conn * ct)90 static inline void nf_ct_deliver_cached_events(const struct nf_conn *ct)
91 {
92 }
93
nf_conntrack_eventmask_report(unsigned int eventmask,struct nf_conn * ct,u32 portid,int report)94 static inline int nf_conntrack_eventmask_report(unsigned int eventmask,
95 struct nf_conn *ct,
96 u32 portid,
97 int report)
98 {
99 return 0;
100 }
101
102 #endif
103
104 static inline void
nf_conntrack_event_cache(enum ip_conntrack_events event,struct nf_conn * ct)105 nf_conntrack_event_cache(enum ip_conntrack_events event, struct nf_conn *ct)
106 {
107 #ifdef CONFIG_NF_CONNTRACK_EVENTS
108 struct net *net = nf_ct_net(ct);
109 struct nf_conntrack_ecache *e;
110
111 if (!rcu_access_pointer(net->ct.nf_conntrack_event_cb))
112 return;
113
114 e = nf_ct_ecache_find(ct);
115 if (e == NULL)
116 return;
117
118 set_bit(event, &e->cache);
119 #endif
120 }
121
122 static inline int
nf_conntrack_event_report(enum ip_conntrack_events event,struct nf_conn * ct,u32 portid,int report)123 nf_conntrack_event_report(enum ip_conntrack_events event, struct nf_conn *ct,
124 u32 portid, int report)
125 {
126 #ifdef CONFIG_NF_CONNTRACK_EVENTS
127 const struct net *net = nf_ct_net(ct);
128
129 if (!rcu_access_pointer(net->ct.nf_conntrack_event_cb))
130 return 0;
131
132 return nf_conntrack_eventmask_report(1 << event, ct, portid, report);
133 #else
134 return 0;
135 #endif
136 }
137
138 static inline int
nf_conntrack_event(enum ip_conntrack_events event,struct nf_conn * ct)139 nf_conntrack_event(enum ip_conntrack_events event, struct nf_conn *ct)
140 {
141 #ifdef CONFIG_NF_CONNTRACK_EVENTS
142 const struct net *net = nf_ct_net(ct);
143
144 if (!rcu_access_pointer(net->ct.nf_conntrack_event_cb))
145 return 0;
146
147 return nf_conntrack_eventmask_report(1 << event, ct, 0, 0);
148 #else
149 return 0;
150 #endif
151 }
152
153 #ifdef CONFIG_NF_CONNTRACK_EVENTS
154
155 struct nf_exp_event {
156 struct nf_conntrack_expect *exp;
157 u32 portid;
158 int report;
159 };
160
161 struct nf_exp_event_notifier {
162 int (*fcn)(unsigned int events, struct nf_exp_event *item);
163 };
164
165 int nf_ct_expect_register_notifier(struct net *net,
166 struct nf_exp_event_notifier *nb);
167 void nf_ct_expect_unregister_notifier(struct net *net,
168 struct nf_exp_event_notifier *nb);
169
170 void nf_ct_expect_event_report(enum ip_conntrack_expect_events event,
171 struct nf_conntrack_expect *exp,
172 u32 portid, int report);
173
174 void nf_conntrack_ecache_pernet_init(struct net *net);
175 void nf_conntrack_ecache_pernet_fini(struct net *net);
176
177 int nf_conntrack_ecache_init(void);
178 void nf_conntrack_ecache_fini(void);
179
180 #else /* CONFIG_NF_CONNTRACK_EVENTS */
181
nf_ct_expect_event_report(enum ip_conntrack_expect_events e,struct nf_conntrack_expect * exp,u32 portid,int report)182 static inline void nf_ct_expect_event_report(enum ip_conntrack_expect_events e,
183 struct nf_conntrack_expect *exp,
184 u32 portid,
185 int report)
186 {
187 }
188
nf_conntrack_ecache_pernet_init(struct net * net)189 static inline void nf_conntrack_ecache_pernet_init(struct net *net)
190 {
191 }
192
nf_conntrack_ecache_pernet_fini(struct net * net)193 static inline void nf_conntrack_ecache_pernet_fini(struct net *net)
194 {
195 }
196
nf_conntrack_ecache_init(void)197 static inline int nf_conntrack_ecache_init(void)
198 {
199 return 0;
200 }
201
nf_conntrack_ecache_fini(void)202 static inline void nf_conntrack_ecache_fini(void)
203 {
204 }
205
206 #endif /* CONFIG_NF_CONNTRACK_EVENTS */
207
nf_conntrack_ecache_delayed_work(struct net * net)208 static inline void nf_conntrack_ecache_delayed_work(struct net *net)
209 {
210 #ifdef CONFIG_NF_CONNTRACK_EVENTS
211 if (!delayed_work_pending(&net->ct.ecache_dwork)) {
212 schedule_delayed_work(&net->ct.ecache_dwork, HZ);
213 net->ct.ecache_dwork_pending = true;
214 }
215 #endif
216 }
217
nf_conntrack_ecache_work(struct net * net)218 static inline void nf_conntrack_ecache_work(struct net *net)
219 {
220 #ifdef CONFIG_NF_CONNTRACK_EVENTS
221 if (net->ct.ecache_dwork_pending) {
222 net->ct.ecache_dwork_pending = false;
223 mod_delayed_work(system_wq, &net->ct.ecache_dwork, 0);
224 }
225 #endif
226 }
227
228 #endif /*_NF_CONNTRACK_ECACHE_H*/
229