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#ifndef _NF_CONNTRACK_SYNPROXY_H
#define _NF_CONNTRACK_SYNPROXY_H
#include <net/netns/generic.h>
struct nf_conn_synproxy {
u32 isn;
u32 its;
u32 tsoff;
};
static inline struct nf_conn_synproxy *nfct_synproxy(const struct nf_conn *ct)
{
#if IS_ENABLED(CONFIG_NETFILTER_SYNPROXY)
return nf_ct_ext_find(ct, NF_CT_EXT_SYNPROXY);
#else
return NULL;
#endif
}
static inline struct nf_conn_synproxy *nfct_synproxy_ext_add(struct nf_conn *ct)
{
#if IS_ENABLED(CONFIG_NETFILTER_SYNPROXY)
return nf_ct_ext_add(ct, NF_CT_EXT_SYNPROXY, GFP_ATOMIC);
#else
return NULL;
#endif
}
static inline bool nf_ct_add_synproxy(struct nf_conn *ct,
const struct nf_conn *tmpl)
{
if (tmpl && nfct_synproxy(tmpl)) {
if (!nfct_seqadj_ext_add(ct))
return false;
if (!nfct_synproxy_ext_add(ct))
return false;
}
return true;
}
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;
};
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;
u32 tsval;
u32 tsecr;
};
struct tcphdr;
struct xt_synproxy_info;
bool synproxy_parse_options(const struct sk_buff *skb, unsigned int doff,
const struct tcphdr *th,
struct synproxy_options *opts);
unsigned int synproxy_options_size(const struct synproxy_options *opts);
void synproxy_build_options(struct tcphdr *th,
const struct synproxy_options *opts);
void synproxy_init_timestamp_cookie(const struct xt_synproxy_info *info,
struct synproxy_options *opts);
void synproxy_check_timestamp_cookie(struct synproxy_options *opts);
unsigned int synproxy_tstamp_adjust(struct sk_buff *skb, unsigned int protoff,
struct tcphdr *th, struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
const struct nf_conn_synproxy *synproxy);
#endif /* _NF_CONNTRACK_SYNPROXY_H */
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