From ac3247baf8ecadf168642e3898b0212c29c79715 Mon Sep 17 00:00:00 2001 From: Harald Welte Date: Tue, 9 Aug 2005 19:28:03 -0700 Subject: [NETFILTER]: connection tracking event notifiers This adds a notifier chain based event mechanism for ip_conntrack state changes. As opposed to the previous implementations in patch-o-matic, we do no longer need a field in the skb to achieve this. Thanks to the valuable input from Patrick McHardy and Rusty on the idea of a per_cpu implementation. Signed-off-by: Harald Welte Signed-off-by: David S. Miller --- include/linux/netfilter_ipv4/ip_conntrack.h | 144 +++++++++++++++++++++++ include/linux/netfilter_ipv4/ip_conntrack_core.h | 17 ++- 2 files changed, 157 insertions(+), 4 deletions(-) (limited to 'include/linux/netfilter_ipv4') diff --git a/include/linux/netfilter_ipv4/ip_conntrack.h b/include/linux/netfilter_ipv4/ip_conntrack.h index 4ed720f0c4c..ae1270c97b5 100644 --- a/include/linux/netfilter_ipv4/ip_conntrack.h +++ b/include/linux/netfilter_ipv4/ip_conntrack.h @@ -65,6 +65,63 @@ enum ip_conntrack_status { /* Both together */ IPS_NAT_DONE_MASK = (IPS_DST_NAT_DONE | IPS_SRC_NAT_DONE), + + /* Connection is dying (removed from lists), can not be unset. */ + IPS_DYING_BIT = 9, + IPS_DYING = (1 << IPS_DYING_BIT), +}; + +/* Connection tracking event bits */ +enum ip_conntrack_events +{ + /* New conntrack */ + IPCT_NEW_BIT = 0, + IPCT_NEW = (1 << IPCT_NEW_BIT), + + /* Expected connection */ + IPCT_RELATED_BIT = 1, + IPCT_RELATED = (1 << IPCT_RELATED_BIT), + + /* Destroyed conntrack */ + IPCT_DESTROY_BIT = 2, + IPCT_DESTROY = (1 << IPCT_DESTROY_BIT), + + /* Timer has been refreshed */ + IPCT_REFRESH_BIT = 3, + IPCT_REFRESH = (1 << IPCT_REFRESH_BIT), + + /* Status has changed */ + IPCT_STATUS_BIT = 4, + IPCT_STATUS = (1 << IPCT_STATUS_BIT), + + /* Update of protocol info */ + IPCT_PROTOINFO_BIT = 5, + IPCT_PROTOINFO = (1 << IPCT_PROTOINFO_BIT), + + /* Volatile protocol info */ + IPCT_PROTOINFO_VOLATILE_BIT = 6, + IPCT_PROTOINFO_VOLATILE = (1 << IPCT_PROTOINFO_VOLATILE_BIT), + + /* New helper for conntrack */ + IPCT_HELPER_BIT = 7, + IPCT_HELPER = (1 << IPCT_HELPER_BIT), + + /* Update of helper info */ + IPCT_HELPINFO_BIT = 8, + IPCT_HELPINFO = (1 << IPCT_HELPINFO_BIT), + + /* Volatile helper info */ + IPCT_HELPINFO_VOLATILE_BIT = 9, + IPCT_HELPINFO_VOLATILE = (1 << IPCT_HELPINFO_VOLATILE_BIT), + + /* NAT info */ + IPCT_NATINFO_BIT = 10, + IPCT_NATINFO = (1 << IPCT_NATINFO_BIT), +}; + +enum ip_conntrack_expect_events { + IPEXP_NEW_BIT = 0, + IPEXP_NEW = (1 << IPEXP_NEW_BIT), }; #ifdef __KERNEL__ @@ -280,6 +337,11 @@ static inline int is_confirmed(struct ip_conntrack *ct) return test_bit(IPS_CONFIRMED_BIT, &ct->status); } +static inline int is_dying(struct ip_conntrack *ct) +{ + return test_bit(IPS_DYING_BIT, &ct->status); +} + extern unsigned int ip_conntrack_htable_size; struct ip_conntrack_stat @@ -303,6 +365,88 @@ struct ip_conntrack_stat #define CONNTRACK_STAT_INC(count) (__get_cpu_var(ip_conntrack_stat).count++) +#ifdef CONFIG_IP_NF_CONNTRACK_EVENTS +#include + +struct ip_conntrack_ecache { + struct ip_conntrack *ct; + unsigned int events; +}; +DECLARE_PER_CPU(struct ip_conntrack_ecache, ip_conntrack_ecache); + +#define CONNTRACK_ECACHE(x) (__get_cpu_var(ip_conntrack_ecache).x) + +extern struct notifier_block *ip_conntrack_chain; +extern struct notifier_block *ip_conntrack_expect_chain; + +static inline int ip_conntrack_register_notifier(struct notifier_block *nb) +{ + return notifier_chain_register(&ip_conntrack_chain, nb); +} + +static inline int ip_conntrack_unregister_notifier(struct notifier_block *nb) +{ + return notifier_chain_unregister(&ip_conntrack_chain, nb); +} + +static inline int +ip_conntrack_expect_register_notifier(struct notifier_block *nb) +{ + return notifier_chain_register(&ip_conntrack_expect_chain, nb); +} + +static inline int +ip_conntrack_expect_unregister_notifier(struct notifier_block *nb) +{ + return notifier_chain_unregister(&ip_conntrack_expect_chain, nb); +} + +static inline void +ip_conntrack_event_cache(enum ip_conntrack_events event, + const struct sk_buff *skb) +{ + struct ip_conntrack_ecache *ecache = + &__get_cpu_var(ip_conntrack_ecache); + + if (unlikely((struct ip_conntrack *) skb->nfct != ecache->ct)) { + if (net_ratelimit()) { + printk(KERN_ERR "ctevent: skb->ct != ecache->ct !!!\n"); + dump_stack(); + } + } + ecache->events |= event; +} + +extern void +ip_conntrack_deliver_cached_events_for(const struct ip_conntrack *ct); +extern void ip_conntrack_event_cache_init(const struct sk_buff *skb); + +static inline void ip_conntrack_event(enum ip_conntrack_events event, + struct ip_conntrack *ct) +{ + if (is_confirmed(ct) && !is_dying(ct)) + notifier_call_chain(&ip_conntrack_chain, event, ct); +} + +static inline void +ip_conntrack_expect_event(enum ip_conntrack_expect_events event, + struct ip_conntrack_expect *exp) +{ + notifier_call_chain(&ip_conntrack_expect_chain, event, exp); +} +#else /* CONFIG_IP_NF_CONNTRACK_EVENTS */ +static inline void ip_conntrack_event_cache(enum ip_conntrack_events event, + const struct sk_buff *skb) {} +static inline void ip_conntrack_event(enum ip_conntrack_events event, + struct ip_conntrack *ct) {} +static inline void ip_conntrack_deliver_cached_events_for( + struct ip_conntrack *ct) {} +static inline void ip_conntrack_event_cache_init(const struct sk_buff *skb) {} +static inline void +ip_conntrack_expect_event(enum ip_conntrack_expect_events event, + struct ip_conntrack_expect *exp) {} +#endif /* CONFIG_IP_NF_CONNTRACK_EVENTS */ + #ifdef CONFIG_IP_NF_NAT_NEEDED static inline int ip_nat_initialized(struct ip_conntrack *conntrack, enum ip_nat_manip_type manip) diff --git a/include/linux/netfilter_ipv4/ip_conntrack_core.h b/include/linux/netfilter_ipv4/ip_conntrack_core.h index 694aec9b478..46eeea1e273 100644 --- a/include/linux/netfilter_ipv4/ip_conntrack_core.h +++ b/include/linux/netfilter_ipv4/ip_conntrack_core.h @@ -38,12 +38,21 @@ extern int __ip_conntrack_confirm(struct sk_buff **pskb); /* Confirm a connection: returns NF_DROP if packet must be dropped. */ static inline int ip_conntrack_confirm(struct sk_buff **pskb) { - if ((*pskb)->nfct - && !is_confirmed((struct ip_conntrack *)(*pskb)->nfct)) - return __ip_conntrack_confirm(pskb); - return NF_ACCEPT; + struct ip_conntrack *ct = (struct ip_conntrack *)(*pskb)->nfct; + int ret = NF_ACCEPT; + + if (ct && !is_confirmed(ct)) + ret = __ip_conntrack_confirm(pskb); + ip_conntrack_deliver_cached_events_for(ct); + + return ret; } +#ifdef CONFIG_IP_NF_CONNTRACK_EVENTS +struct ip_conntrack_ecache; +extern void __ip_ct_deliver_cached_events(struct ip_conntrack_ecache *ec); +#endif + extern struct list_head *ip_conntrack_hash; extern struct list_head ip_conntrack_expect_list; extern rwlock_t ip_conntrack_lock; -- cgit v1.2.3