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/*
* connection tracking event cache.
*/
#ifndef _NF_CONNTRACK_ECACHE_H
#define _NF_CONNTRACK_ECACHE_H
#include <net/netfilter/nf_conntrack.h>
#include <net/net_namespace.h>
#include <net/netfilter/nf_conntrack_expect.h>
#include <linux/netfilter/nf_conntrack_common.h>
#include <linux/netfilter/nf_conntrack_tuple_common.h>
#include <net/netfilter/nf_conntrack_extend.h>
struct nf_conntrack_ecache {
unsigned long cache; /* bitops want long */
unsigned long missed; /* missed events */
u16 ctmask; /* bitmask of ct events to be delivered */
u16 expmask; /* bitmask of expect events to be delivered */
u32 pid; /* netlink pid of destroyer */
};
static inline struct nf_conntrack_ecache *
nf_ct_ecache_find(const struct nf_conn *ct)
{
return nf_ct_ext_find(ct, NF_CT_EXT_ECACHE);
}
static inline struct nf_conntrack_ecache *
nf_ct_ecache_ext_add(struct nf_conn *ct, u16 ctmask, u16 expmask, gfp_t gfp)
{
struct net *net = nf_ct_net(ct);
struct nf_conntrack_ecache *e;
if (!ctmask && !expmask && net->ct.sysctl_events) {
ctmask = ~0;
expmask = ~0;
}
if (!ctmask && !expmask)
return NULL;
e = nf_ct_ext_add(ct, NF_CT_EXT_ECACHE, gfp);
if (e) {
e->ctmask = ctmask;
e->expmask = expmask;
}
return e;
};
#ifdef CONFIG_NF_CONNTRACK_EVENTS
/* This structure is passed to event handler */
struct nf_ct_event {
struct nf_conn *ct;
u32 pid;
int report;
};
struct nf_ct_event_notifier {
int (*fcn)(unsigned int events, struct nf_ct_event *item);
};
extern struct nf_ct_event_notifier *nf_conntrack_event_cb;
extern int nf_conntrack_register_notifier(struct nf_ct_event_notifier *nb);
extern void nf_conntrack_unregister_notifier(struct nf_ct_event_notifier *nb);
extern void nf_ct_deliver_cached_events(struct nf_conn *ct);
static inline void
nf_conntrack_event_cache(enum ip_conntrack_events event, struct nf_conn *ct)
{
struct nf_conntrack_ecache *e;
if (nf_conntrack_event_cb == NULL)
return;
e = nf_ct_ecache_find(ct);
if (e == NULL)
return;
set_bit(event, &e->cache);
}
static inline int
nf_conntrack_eventmask_report(unsigned int eventmask,
struct nf_conn *ct,
u32 pid,
int report)
{
int ret = 0;
struct nf_ct_event_notifier *notify;
struct nf_conntrack_ecache *e;
rcu_read_lock();
notify = rcu_dereference(nf_conntrack_event_cb);
if (notify == NULL)
goto out_unlock;
e = nf_ct_ecache_find(ct);
if (e == NULL)
goto out_unlock;
if (nf_ct_is_confirmed(ct) && !nf_ct_is_dying(ct)) {
struct nf_ct_event item = {
.ct = ct,
.pid = e->pid ? e->pid : pid,
.report = report
};
/* This is a resent of a destroy event? If so, skip missed */
unsigned long missed = e->pid ? 0 : e->missed;
if (!((eventmask | missed) & e->ctmask))
goto out_unlock;
ret = notify->fcn(eventmask | missed, &item);
if (unlikely(ret < 0 || missed)) {
spin_lock_bh(&ct->lock);
if (ret < 0) {
/* This is a destroy event that has been
* triggered by a process, we store the PID
* to include it in the retransmission. */
if (eventmask & (1 << IPCT_DESTROY) &&
e->pid == 0 && pid != 0)
e->pid = pid;
else
e->missed |= eventmask;
} else
e->missed &= ~missed;
spin_unlock_bh(&ct->lock);
}
}
out_unlock:
rcu_read_unlock();
return ret;
}
static inline int
nf_conntrack_event_report(enum ip_conntrack_events event, struct nf_conn *ct,
u32 pid, int report)
{
return nf_conntrack_eventmask_report(1 << event, ct, pid, report);
}
static inline int
nf_conntrack_event(enum ip_conntrack_events event, struct nf_conn *ct)
{
return nf_conntrack_eventmask_report(1 << event, ct, 0, 0);
}
struct nf_exp_event {
struct nf_conntrack_expect *exp;
u32 pid;
int report;
};
struct nf_exp_event_notifier {
int (*fcn)(unsigned int events, struct nf_exp_event *item);
};
extern struct nf_exp_event_notifier *nf_expect_event_cb;
extern int nf_ct_expect_register_notifier(struct nf_exp_event_notifier *nb);
extern void nf_ct_expect_unregister_notifier(struct nf_exp_event_notifier *nb);
static inline void
nf_ct_expect_event_report(enum ip_conntrack_expect_events event,
struct nf_conntrack_expect *exp,
u32 pid,
int report)
{
struct nf_exp_event_notifier *notify;
struct nf_conntrack_ecache *e;
rcu_read_lock();
notify = rcu_dereference(nf_expect_event_cb);
if (notify == NULL)
goto out_unlock;
e = nf_ct_ecache_find(exp->master);
if (e == NULL)
goto out_unlock;
if (e->expmask & (1 << event)) {
struct nf_exp_event item = {
.exp = exp,
.pid = pid,
.report = report
};
notify->fcn(1 << event, &item);
}
out_unlock:
rcu_read_unlock();
}
static inline void
nf_ct_expect_event(enum ip_conntrack_expect_events event,
struct nf_conntrack_expect *exp)
{
nf_ct_expect_event_report(event, exp, 0, 0);
}
extern int nf_conntrack_ecache_init(struct net *net);
extern void nf_conntrack_ecache_fini(struct net *net);
#else /* CONFIG_NF_CONNTRACK_EVENTS */
static inline void nf_conntrack_event_cache(enum ip_conntrack_events event,
struct nf_conn *ct) {}
static inline int nf_conntrack_eventmask_report(unsigned int eventmask,
struct nf_conn *ct,
u32 pid,
int report) { return 0; }
static inline int nf_conntrack_event(enum ip_conntrack_events event,
struct nf_conn *ct) { return 0; }
static inline int nf_conntrack_event_report(enum ip_conntrack_events event,
struct nf_conn *ct,
u32 pid,
int report) { return 0; }
static inline void nf_ct_deliver_cached_events(const struct nf_conn *ct) {}
static inline void nf_ct_expect_event(enum ip_conntrack_expect_events event,
struct nf_conntrack_expect *exp) {}
static inline void nf_ct_expect_event_report(enum ip_conntrack_expect_events e,
struct nf_conntrack_expect *exp,
u32 pid,
int report) {}
static inline int nf_conntrack_ecache_init(struct net *net)
{
return 0;
}
static inline void nf_conntrack_ecache_fini(struct net *net)
{
}
#endif /* CONFIG_NF_CONNTRACK_EVENTS */
#endif /*_NF_CONNTRACK_ECACHE_H*/
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