1/* 2 * connection tracking helpers. 3 * 4 * 16 Dec 2003: Yasuyuki Kozakai @USAGI <yasuyuki.kozakai@toshiba.co.jp> 5 * - generalize L3 protocol dependent part. 6 * 7 * Derived from include/linux/netfiter_ipv4/ip_conntrack_helper.h 8 */ 9 10#ifndef _NF_CONNTRACK_HELPER_H 11#define _NF_CONNTRACK_HELPER_H 12#include <net/netfilter/nf_conntrack.h> 13#include <net/netfilter/nf_conntrack_extend.h> 14 15struct module; 16 17#define NF_CT_HELPER_NAME_LEN 16 18 19struct nf_conntrack_helper { 20 struct hlist_node hnode; /* Internal use. */ 21 22 const char *name; /* name of the module */ 23 struct module *me; /* pointer to self */ 24 const struct nf_conntrack_expect_policy *expect_policy; 25 26 /* Tuple of things we will help (compared against server response) */ 27 struct nf_conntrack_tuple tuple; 28 29 /* Function to call when data passes; return verdict, or -1 to 30 invalidate. */ 31 int (*help)(struct sk_buff *skb, 32 unsigned int protoff, 33 struct nf_conn *ct, 34 enum ip_conntrack_info conntrackinfo); 35 36 void (*destroy)(struct nf_conn *ct); 37 38 int (*to_nlattr)(struct sk_buff *skb, const struct nf_conn *ct); 39 unsigned int expect_class_max; 40}; 41 42extern struct nf_conntrack_helper * 43__nf_conntrack_helper_find(const char *name, u16 l3num, u8 protonum); 44 45extern struct nf_conntrack_helper * 46nf_conntrack_helper_try_module_get(const char *name, u16 l3num, u8 protonum); 47 48extern int nf_conntrack_helper_register(struct nf_conntrack_helper *); 49extern void nf_conntrack_helper_unregister(struct nf_conntrack_helper *); 50 51extern struct nf_conn_help *nf_ct_helper_ext_add(struct nf_conn *ct, gfp_t gfp); 52 53extern int __nf_ct_try_assign_helper(struct nf_conn *ct, struct nf_conn *tmpl, 54 gfp_t flags); 55 56extern void nf_ct_helper_destroy(struct nf_conn *ct); 57 58static inline struct nf_conn_help *nfct_help(const struct nf_conn *ct) 59{ 60 return nf_ct_ext_find(ct, NF_CT_EXT_HELPER); 61} 62 63extern int nf_conntrack_helper_init(void); 64extern void nf_conntrack_helper_fini(void); 65 66#endif /*_NF_CONNTRACK_HELPER_H*/ 67