include/net/netfilter/nf_conntrack_ecache.h

   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 *
  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 *
  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 /* This structure is passed to event handler */
  68 struct nf_ct_event {
  69         struct nf_conn *ct;
  70         u32 portid;
  71         int report;
  72 };
  73
  74 struct nf_ct_event_notifier {
  75         int (*fcn)(unsigned int events, struct nf_ct_event *item);
  76 };
  77
  78 int nf_conntrack_register_notifier(struct net *net,
  79                                    struct nf_ct_event_notifier *nb);
  80 void nf_conntrack_unregister_notifier(struct net *net,
  81                                       struct nf_ct_event_notifier *nb);
  82
  83 void nf_ct_deliver_cached_events(struct nf_conn *ct);
  84 int nf_conntrack_eventmask_report(unsigned int eventmask, struct nf_conn *ct,
  85                                   u32 portid, int report);
  86
  87 static inline void
  88 nf_conntrack_event_cache(enum ip_conntrack_events event, struct nf_conn *ct)
  89 {
  90         struct net *net = nf_ct_net(ct);
  91         struct nf_conntrack_ecache *e;
  92
  93         if (!rcu_access_pointer(net->ct.nf_conntrack_event_cb))
  94                 return;
  95
  96         e = nf_ct_ecache_find(ct);
  97         if (e == NULL)
  98                 return;
  99
 100         set_bit(event, &e->cache);
 101 }
 102
 103 static inline int
 104 nf_conntrack_event_report(enum ip_conntrack_events event, struct nf_conn *ct,
 105                           u32 portid, int report)
 106 {
 107         const struct net *net = nf_ct_net(ct);
 108
 109         if (!rcu_access_pointer(net->ct.nf_conntrack_event_cb))
 110                 return 0;
 111
 112         return nf_conntrack_eventmask_report(1 << event, ct, portid, report);
 113 }
 114
 115 static inline int
 116 nf_conntrack_event(enum ip_conntrack_events event, struct nf_conn *ct)
 117 {
 118         const struct net *net = nf_ct_net(ct);
 119
 120         if (!rcu_access_pointer(net->ct.nf_conntrack_event_cb))
 121                 return 0;
 122
 123         return nf_conntrack_eventmask_report(1 << event, ct, 0, 0);
 124 }
 125
 126 struct nf_exp_event {
 127         struct nf_conntrack_expect *exp;
 128         u32 portid;
 129         int report;
 130 };
 131
 132 struct nf_exp_event_notifier {
 133         int (*fcn)(unsigned int events, struct nf_exp_event *item);
 134 };
 135
 136 int nf_ct_expect_register_notifier(struct net *net,
 137                                    struct nf_exp_event_notifier *nb);
 138 void nf_ct_expect_unregister_notifier(struct net *net,
 139                                       struct nf_exp_event_notifier *nb);
 140
 141 void nf_ct_expect_event_report(enum ip_conntrack_expect_events event,
 142                                struct nf_conntrack_expect *exp,
 143                                u32 portid, int report);
 144
 145 int nf_conntrack_ecache_pernet_init(struct net *net);
 146 void nf_conntrack_ecache_pernet_fini(struct net *net);
 147
 148 int nf_conntrack_ecache_init(void);
 149 void nf_conntrack_ecache_fini(void);
 150
 151 static inline void nf_conntrack_ecache_delayed_work(struct net *net)
 152 {
 153         if (!delayed_work_pending(&net->ct.ecache_dwork)) {
 154                 schedule_delayed_work(&net->ct.ecache_dwork, HZ);
 155                 net->ct.ecache_dwork_pending = true;
 156         }
 157 }
 158
 159 static inline void nf_conntrack_ecache_work(struct net *net)
 160 {
 161         if (net->ct.ecache_dwork_pending) {
 162                 net->ct.ecache_dwork_pending = false;
 163                 mod_delayed_work(system_wq, &net->ct.ecache_dwork, 0);
 164         }
 165 }
 166 #else /* CONFIG_NF_CONNTRACK_EVENTS */
 167 static inline void nf_conntrack_event_cache(enum ip_conntrack_events event,
 168                                             struct nf_conn *ct) {}
 169 static inline int nf_conntrack_eventmask_report(unsigned int eventmask,
 170                                                 struct nf_conn *ct,
 171                                                 u32 portid,
 172                                                 int report) { return 0; }
 173 static inline int nf_conntrack_event(enum ip_conntrack_events event,
 174                                      struct nf_conn *ct) { return 0; }
 175 static inline int nf_conntrack_event_report(enum ip_conntrack_events event,
 176                                             struct nf_conn *ct,
 177                                             u32 portid,
 178                                             int report) { return 0; }
 179 static inline void nf_ct_deliver_cached_events(const struct nf_conn *ct) {}
 180 static inline void nf_ct_expect_event_report(enum ip_conntrack_expect_events e,
 181                                              struct nf_conntrack_expect *exp,
 182                                              u32 portid,
 183                                              int report) {}
 184
 185 static inline int nf_conntrack_ecache_pernet_init(struct net *net)
 186 {
 187         return 0;
 188 }
 189
 190 static inline void nf_conntrack_ecache_pernet_fini(struct net *net)
 191 {
 192 }
 193
 194 static inline int nf_conntrack_ecache_init(void)
 195 {
 196         return 0;
 197 }
 198
 199 static inline void nf_conntrack_ecache_fini(void)
 200 {
 201 }
 202
 203 static inline void nf_conntrack_ecache_delayed_work(struct net *net)
 204 {
 205 }
 206
 207 static inline void nf_conntrack_ecache_work(struct net *net)
 208 {
 209 }
 210 #endif /* CONFIG_NF_CONNTRACK_EVENTS */
 211
 212 #endif /*_NF_CONNTRACK_ECACHE_H*/
 213