/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _NF_SYNPROXY_SHARED_H
#define _NF_SYNPROXY_SHARED_H
#include <linux/module.h>
#include <linux/skbuff.h>
#include <net/ip6_checksum.h>
#include <net/ip6_route.h>
#include <net/tcp.h>
#include <net/netfilter/nf_conntrack_seqadj.h>
#include <net/netfilter/nf_conntrack_synproxy.h>
struct synproxy_stats {
unsigned int syn_received;
unsigned int cookie_invalid;
unsigned int cookie_valid;
unsigned int cookie_retrans;
unsigned int conn_reopened;
};
struct synproxy_net {
struct nf_conn *tmpl;
struct synproxy_stats __percpu *stats;
unsigned int hook_ref4;
unsigned int hook_ref6;
};
extern unsigned int synproxy_net_id;
static inline struct synproxy_net *synproxy_pernet(struct net *net)
{
return net_generic(net, synproxy_net_id);
}
struct synproxy_options {
u8 options;
u8 wscale;
u16 mss_option;
u16 mss_encode;
u32 tsval;
u32 tsecr;
};
struct nf_synproxy_info;
bool synproxy_parse_options(const struct sk_buff *skb, unsigned int doff,
const struct tcphdr *th,
struct synproxy_options *opts);
void synproxy_init_timestamp_cookie(const struct nf_synproxy_info *info,
struct synproxy_options *opts);
void synproxy_send_client_synack(struct net *net, const struct sk_buff *skb,
const struct tcphdr *th,
const struct synproxy_options *opts);
bool synproxy_recv_client_ack(struct net *net,
const struct sk_buff *skb,
const struct tcphdr *th,
struct synproxy_options *opts, u32 recv_seq);
struct nf_hook_state;
unsigned int ipv4_synproxy_hook(void *priv, struct sk_buff *skb,
const struct nf_hook_state *nhs);
int nf_synproxy_ipv4_init(struct synproxy_net *snet, struct net *net);
void nf_synproxy_ipv4_fini(struct synproxy_net *snet, struct net *net);
#if IS_ENABLED(CONFIG_IPV6)
void synproxy_send_client_synack_ipv6(struct net *net,
const struct sk_buff *skb,
const struct tcphdr *th,
const struct synproxy_options *opts);
bool synproxy_recv_client_ack_ipv6(struct net *net, const struct sk_buff *skb,
const struct tcphdr *th,
struct synproxy_options *opts, u32 recv_seq);
unsigned int ipv6_synproxy_hook(void *priv, struct sk_buff *skb,
const struct nf_hook_state *nhs);
int nf_synproxy_ipv6_init(struct synproxy_net *snet, struct net *net);
void nf_synproxy_ipv6_fini(struct synproxy_net *snet, struct net *net);
#else
static inline int
nf_synproxy_ipv6_init(struct synproxy_net *snet, struct net *net) { return 0; }
static inline void
nf_synproxy_ipv6_fini(struct synproxy_net *snet, struct net *net) {};
#endif /* CONFIG_IPV6 */
#endif /* _NF_SYNPROXY_SHARED_H */