Commit | Line | Data |
---|---|---|
f6180121 MJ |
1 | /* Event cache for netfilter. */ |
2 | ||
3 | /* (C) 1999-2001 Paul `Rusty' Russell | |
4 | * (C) 2002-2006 Netfilter Core Team <coreteam@netfilter.org> | |
5 | * (C) 2003,2004 USAGI/WIDE Project <http://www.linux-ipv6.org> | |
6 | * | |
7 | * This program is free software; you can redistribute it and/or modify | |
8 | * it under the terms of the GNU General Public License version 2 as | |
9 | * published by the Free Software Foundation. | |
10 | */ | |
11 | ||
12 | #include <linux/types.h> | |
13 | #include <linux/netfilter.h> | |
14 | #include <linux/skbuff.h> | |
15 | #include <linux/vmalloc.h> | |
16 | #include <linux/stddef.h> | |
17 | #include <linux/err.h> | |
18 | #include <linux/percpu.h> | |
19 | #include <linux/notifier.h> | |
20 | #include <linux/kernel.h> | |
21 | #include <linux/netdevice.h> | |
22 | ||
23 | #include <net/netfilter/nf_conntrack.h> | |
f6180121 MJ |
24 | #include <net/netfilter/nf_conntrack_core.h> |
25 | ||
26 | ATOMIC_NOTIFIER_HEAD(nf_conntrack_chain); | |
13b18339 PM |
27 | EXPORT_SYMBOL_GPL(nf_conntrack_chain); |
28 | ||
6823645d PM |
29 | ATOMIC_NOTIFIER_HEAD(nf_ct_expect_chain); |
30 | EXPORT_SYMBOL_GPL(nf_ct_expect_chain); | |
f6180121 | 31 | |
f6180121 MJ |
32 | /* deliver cached events and clear cache entry - must be called with locally |
33 | * disabled softirqs */ | |
34 | static inline void | |
35 | __nf_ct_deliver_cached_events(struct nf_conntrack_ecache *ecache) | |
36 | { | |
37 | if (nf_ct_is_confirmed(ecache->ct) && !nf_ct_is_dying(ecache->ct) | |
19abb7b0 PNA |
38 | && ecache->events) { |
39 | struct nf_ct_event item = { | |
40 | .ct = ecache->ct, | |
41 | .pid = 0, | |
42 | .report = 0 | |
43 | }; | |
44 | ||
45 | atomic_notifier_call_chain(&nf_conntrack_chain, | |
46 | ecache->events, | |
47 | &item); | |
48 | } | |
f6180121 MJ |
49 | |
50 | ecache->events = 0; | |
51 | nf_ct_put(ecache->ct); | |
52 | ecache->ct = NULL; | |
53 | } | |
54 | ||
55 | /* Deliver all cached events for a particular conntrack. This is called | |
56 | * by code prior to async packet handling for freeing the skb */ | |
57 | void nf_ct_deliver_cached_events(const struct nf_conn *ct) | |
58 | { | |
6058fa6b | 59 | struct net *net = nf_ct_net(ct); |
f6180121 MJ |
60 | struct nf_conntrack_ecache *ecache; |
61 | ||
62 | local_bh_disable(); | |
6058fa6b | 63 | ecache = per_cpu_ptr(net->ct.ecache, raw_smp_processor_id()); |
f6180121 MJ |
64 | if (ecache->ct == ct) |
65 | __nf_ct_deliver_cached_events(ecache); | |
66 | local_bh_enable(); | |
67 | } | |
13b18339 | 68 | EXPORT_SYMBOL_GPL(nf_ct_deliver_cached_events); |
f6180121 MJ |
69 | |
70 | /* Deliver cached events for old pending events, if current conntrack != old */ | |
71 | void __nf_ct_event_cache_init(struct nf_conn *ct) | |
72 | { | |
6058fa6b | 73 | struct net *net = nf_ct_net(ct); |
f6180121 MJ |
74 | struct nf_conntrack_ecache *ecache; |
75 | ||
76 | /* take care of delivering potentially old events */ | |
6058fa6b | 77 | ecache = per_cpu_ptr(net->ct.ecache, raw_smp_processor_id()); |
f6180121 MJ |
78 | BUG_ON(ecache->ct == ct); |
79 | if (ecache->ct) | |
80 | __nf_ct_deliver_cached_events(ecache); | |
81 | /* initialize for this conntrack/packet */ | |
82 | ecache->ct = ct; | |
83 | nf_conntrack_get(&ct->ct_general); | |
84 | } | |
13b18339 | 85 | EXPORT_SYMBOL_GPL(__nf_ct_event_cache_init); |
f6180121 MJ |
86 | |
87 | /* flush the event cache - touches other CPU's data and must not be called | |
88 | * while packets are still passing through the code */ | |
6058fa6b | 89 | void nf_ct_event_cache_flush(struct net *net) |
f6180121 MJ |
90 | { |
91 | struct nf_conntrack_ecache *ecache; | |
92 | int cpu; | |
93 | ||
94 | for_each_possible_cpu(cpu) { | |
6058fa6b | 95 | ecache = per_cpu_ptr(net->ct.ecache, cpu); |
f6180121 MJ |
96 | if (ecache->ct) |
97 | nf_ct_put(ecache->ct); | |
98 | } | |
99 | } | |
100 | ||
6058fa6b AD |
101 | int nf_conntrack_ecache_init(struct net *net) |
102 | { | |
103 | net->ct.ecache = alloc_percpu(struct nf_conntrack_ecache); | |
104 | if (!net->ct.ecache) | |
105 | return -ENOMEM; | |
106 | return 0; | |
107 | } | |
108 | ||
109 | void nf_conntrack_ecache_fini(struct net *net) | |
110 | { | |
111 | free_percpu(net->ct.ecache); | |
112 | } | |
113 | ||
010c7d6f PM |
114 | int nf_conntrack_register_notifier(struct notifier_block *nb) |
115 | { | |
116 | return atomic_notifier_chain_register(&nf_conntrack_chain, nb); | |
117 | } | |
118 | EXPORT_SYMBOL_GPL(nf_conntrack_register_notifier); | |
119 | ||
120 | int nf_conntrack_unregister_notifier(struct notifier_block *nb) | |
121 | { | |
122 | return atomic_notifier_chain_unregister(&nf_conntrack_chain, nb); | |
123 | } | |
124 | EXPORT_SYMBOL_GPL(nf_conntrack_unregister_notifier); | |
125 | ||
6823645d | 126 | int nf_ct_expect_register_notifier(struct notifier_block *nb) |
010c7d6f | 127 | { |
6823645d | 128 | return atomic_notifier_chain_register(&nf_ct_expect_chain, nb); |
010c7d6f | 129 | } |
6823645d | 130 | EXPORT_SYMBOL_GPL(nf_ct_expect_register_notifier); |
010c7d6f | 131 | |
6823645d | 132 | int nf_ct_expect_unregister_notifier(struct notifier_block *nb) |
010c7d6f | 133 | { |
6823645d | 134 | return atomic_notifier_chain_unregister(&nf_ct_expect_chain, nb); |
010c7d6f | 135 | } |
6823645d | 136 | EXPORT_SYMBOL_GPL(nf_ct_expect_unregister_notifier); |