1 #ifndef _NFNETLINK_H 2 #define _NFNETLINK_H 3 4 5 #include <linux/netlink.h> 6 #include <linux/capability.h> 7 #include <net/netlink.h> 8 #include <uapi/linux/netfilter/nfnetlink.h> 9 10 struct nfnl_callback { 11 int (*call)(struct net *net, struct sock *nl, struct sk_buff *skb, 12 const struct nlmsghdr *nlh, 13 const struct nlattr * const cda[]); 14 int (*call_rcu)(struct net *net, struct sock *nl, struct sk_buff *skb, 15 const struct nlmsghdr *nlh, 16 const struct nlattr * const cda[]); 17 int (*call_batch)(struct net *net, struct sock *nl, struct sk_buff *skb, 18 const struct nlmsghdr *nlh, 19 const struct nlattr * const cda[]); 20 const struct nla_policy *policy; /* netlink attribute policy */ 21 const u_int16_t attr_count; /* number of nlattr's */ 22 }; 23 24 struct nfnetlink_subsystem { 25 const char *name; 26 __u8 subsys_id; /* nfnetlink subsystem ID */ 27 __u8 cb_count; /* number of callbacks */ 28 const struct nfnl_callback *cb; /* callback for individual types */ 29 int (*commit)(struct net *net, struct sk_buff *skb); 30 int (*abort)(struct net *net, struct sk_buff *skb); 31 }; 32 33 int nfnetlink_subsys_register(const struct nfnetlink_subsystem *n); 34 int nfnetlink_subsys_unregister(const struct nfnetlink_subsystem *n); 35 36 int nfnetlink_has_listeners(struct net *net, unsigned int group); 37 int nfnetlink_send(struct sk_buff *skb, struct net *net, u32 portid, 38 unsigned int group, int echo, gfp_t flags); 39 int nfnetlink_set_err(struct net *net, u32 portid, u32 group, int error); 40 int nfnetlink_unicast(struct sk_buff *skb, struct net *net, u32 portid, 41 int flags); 42 43 void nfnl_lock(__u8 subsys_id); 44 void nfnl_unlock(__u8 subsys_id); 45 #ifdef CONFIG_PROVE_LOCKING 46 bool lockdep_nfnl_is_held(__u8 subsys_id); 47 #else 48 static inline bool lockdep_nfnl_is_held(__u8 subsys_id) 49 { 50 return true; 51 } 52 #endif /* CONFIG_PROVE_LOCKING */ 53 54 /* 55 * nfnl_dereference - fetch RCU pointer when updates are prevented by subsys mutex 56 * 57 * @p: The pointer to read, prior to dereferencing 58 * @ss: The nfnetlink subsystem ID 59 * 60 * Return the value of the specified RCU-protected pointer, but omit 61 * both the smp_read_barrier_depends() and the ACCESS_ONCE(), because 62 * caller holds the NFNL subsystem mutex. 63 */ 64 #define nfnl_dereference(p, ss) \ 65 rcu_dereference_protected(p, lockdep_nfnl_is_held(ss)) 66 67 #define MODULE_ALIAS_NFNL_SUBSYS(subsys) \ 68 MODULE_ALIAS("nfnetlink-subsys-" __stringify(subsys)) 69 70 #endif /* _NFNETLINK_H */ 71