nf_conntrack_l4proto.h
/* SPDX-License-Identifier: GPL-2.0 */
/*
* Header for use in defining a given L4 protocol for connection tracking.
*
* 16 Dec 2003: Yasuyuki Kozakai @USAGI <yasuyuki.kozakai@toshiba.co.jp>
* - generalized L3 protocol dependent part.
*
* Derived from include/linux/netfiter_ipv4/ip_conntrack_protcol.h
*/
#ifndef _NF_CONNTRACK_L4PROTO_H
#define _NF_CONNTRACK_L4PROTO_H
#include <linux/netlink.h>
#include <net/netlink.h>
#include <net/netfilter/nf_conntrack.h>
#include <net/netns/generic.h>
struct seq_file;
struct nf_conntrack_l4proto {
/* L3 Protocol number. */
u_int16_t l3proto;
/* L4 Protocol number. */
u_int8_t l4proto;
/* Resolve clashes on insertion races. */
bool allow_clash;
/* protoinfo nlattr size, closes a hole */
u16 nlattr_size;
/* Try to fill in the third arg: dataoff is offset past network protocol
hdr. Return true if possible. */
bool (*pkt_to_tuple)(const struct sk_buff *skb, unsigned int dataoff,
struct net *net, struct nf_conntrack_tuple *tuple);
/* Invert the per-proto part of the tuple: ie. turn xmit into reply.
* Only used by icmp, most protocols use a generic version.
*/
bool (*invert_tuple)(struct nf_conntrack_tuple *inverse,
const struct nf_conntrack_tuple *orig);
/* Returns verdict for packet, or -1 for invalid. */
int (*packet)(struct nf_conn *ct,
const struct sk_buff *skb,
unsigned int dataoff,
enum ip_conntrack_info ctinfo);
/* Called when a new connection for this protocol found;
* returns TRUE if it's OK. If so, packet() called next. */
bool (*new)(struct nf_conn *ct, const struct sk_buff *skb,
unsigned int dataoff);
/* Called when a conntrack entry is destroyed */
void (*destroy)(struct nf_conn *ct);
int (*error)(struct net *net, struct nf_conn *tmpl, struct sk_buff *skb,
unsigned int dataoff,
u_int8_t pf, unsigned int hooknum);
/* called by gc worker if table is full */
bool (*can_early_drop)(const struct nf_conn *ct);
/* convert protoinfo to nfnetink attributes */
int (*to_nlattr)(struct sk_buff *skb, struct nlattr *nla,
struct nf_conn *ct);
/* convert nfnetlink attributes to protoinfo */
int (*from_nlattr)(struct nlattr *tb[], struct nf_conn *ct);
int (*tuple_to_nlattr)(struct sk_buff *skb,
const struct nf_conntrack_tuple *t);
/* Calculate tuple nlattr size */
unsigned int (*nlattr_tuple_size)(void);
int (*nlattr_to_tuple)(struct nlattr *tb[],
struct nf_conntrack_tuple *t);
const struct nla_policy *nla_policy;
struct {
int (*nlattr_to_obj)(struct nlattr *tb[],
struct net *net, void *data);
int (*obj_to_nlattr)(struct sk_buff *skb, const void *data);
u16 obj_size;
u16 nlattr_max;
const struct nla_policy *nla_policy;
} ctnl_timeout;
#ifdef CONFIG_NF_CONNTRACK_PROCFS
/* Print out the private part of the conntrack. */
void (*print_conntrack)(struct seq_file *s, struct nf_conn *);
#endif
unsigned int *net_id;
/* Init l4proto pernet data */
int (*init_net)(struct net *net, u_int16_t proto);
/* Return the per-net protocol part. */
struct nf_proto_net *(*get_net_proto)(struct net *net);
/* Module (if any) which this is connected to. */
struct module *me;
};
/* Existing built-in generic protocol */
extern const struct nf_conntrack_l4proto nf_conntrack_l4proto_generic;
#define MAX_NF_CT_PROTO 256
const struct nf_conntrack_l4proto *__nf_ct_l4proto_find(u_int16_t l3proto,
u_int8_t l4proto);
const struct nf_conntrack_l4proto *nf_ct_l4proto_find_get(u_int16_t l3proto,
u_int8_t l4proto);
void nf_ct_l4proto_put(const struct nf_conntrack_l4proto *p);
/* Protocol pernet registration. */
int nf_ct_l4proto_pernet_register_one(struct net *net,
const struct nf_conntrack_l4proto *proto);
void nf_ct_l4proto_pernet_unregister_one(struct net *net,
const struct nf_conntrack_l4proto *proto);
int nf_ct_l4proto_pernet_register(struct net *net,
const struct nf_conntrack_l4proto *const proto[],
unsigned int num_proto);
void nf_ct_l4proto_pernet_unregister(struct net *net,
const struct nf_conntrack_l4proto *const proto[],
unsigned int num_proto);
/* Protocol global registration. */
int nf_ct_l4proto_register_one(const struct nf_conntrack_l4proto *proto);
void nf_ct_l4proto_unregister_one(const struct nf_conntrack_l4proto *proto);
/* Generic netlink helpers */
int nf_ct_port_tuple_to_nlattr(struct sk_buff *skb,
const struct nf_conntrack_tuple *tuple);
int nf_ct_port_nlattr_to_tuple(struct nlattr *tb[],
struct nf_conntrack_tuple *t);
unsigned int nf_ct_port_nlattr_tuple_size(void);
extern const struct nla_policy nf_ct_port_nla_policy[];
#ifdef CONFIG_SYSCTL
__printf(3, 4) __cold
void nf_ct_l4proto_log_invalid(const struct sk_buff *skb,
const struct nf_conn *ct,
const char *fmt, ...);
__printf(5, 6) __cold
void nf_l4proto_log_invalid(const struct sk_buff *skb,
struct net *net,
u16 pf, u8 protonum,
const char *fmt, ...);
#else
static inline __printf(5, 6) __cold
void nf_l4proto_log_invalid(const struct sk_buff *skb, struct net *net,
u16 pf, u8 protonum, const char *fmt, ...) {}
static inline __printf(3, 4) __cold
void nf_ct_l4proto_log_invalid(const struct sk_buff *skb,
const struct nf_conn *ct,
const char *fmt, ...) { }
#endif /* CONFIG_SYSCTL */
#endif /*_NF_CONNTRACK_PROTOCOL_H*/