1 #ifndef _NF_CONNTRACK_SYNPROXY_H 2 #define _NF_CONNTRACK_SYNPROXY_H 3 4 #include <net/netns/generic.h> 5 6 struct nf_conn_synproxy { 7 u32 isn; 8 u32 its; 9 u32 tsoff; 10 }; 11 12 static inline struct nf_conn_synproxy *nfct_synproxy(const struct nf_conn *ct) 13 { 14 #if IS_ENABLED(CONFIG_NETFILTER_SYNPROXY) 15 return nf_ct_ext_find(ct, NF_CT_EXT_SYNPROXY); 16 #else 17 return NULL; 18 #endif 19 } 20 21 static inline struct nf_conn_synproxy *nfct_synproxy_ext_add(struct nf_conn *ct) 22 { 23 #if IS_ENABLED(CONFIG_NETFILTER_SYNPROXY) 24 return nf_ct_ext_add(ct, NF_CT_EXT_SYNPROXY, GFP_ATOMIC); 25 #else 26 return NULL; 27 #endif 28 } 29 30 static inline bool nf_ct_add_synproxy(struct nf_conn *ct, 31 const struct nf_conn *tmpl) 32 { 33 if (tmpl && nfct_synproxy(tmpl)) { 34 if (!nfct_seqadj_ext_add(ct)) 35 return false; 36 37 if (!nfct_synproxy_ext_add(ct)) 38 return false; 39 } 40 41 return true; 42 } 43 44 struct synproxy_stats { 45 unsigned int syn_received; 46 unsigned int cookie_invalid; 47 unsigned int cookie_valid; 48 unsigned int cookie_retrans; 49 unsigned int conn_reopened; 50 }; 51 52 struct synproxy_net { 53 struct nf_conn *tmpl; 54 struct synproxy_stats __percpu *stats; 55 }; 56 57 extern int synproxy_net_id; 58 static inline struct synproxy_net *synproxy_pernet(struct net *net) 59 { 60 return net_generic(net, synproxy_net_id); 61 } 62 63 struct synproxy_options { 64 u8 options; 65 u8 wscale; 66 u16 mss; 67 u32 tsval; 68 u32 tsecr; 69 }; 70 71 struct tcphdr; 72 struct xt_synproxy_info; 73 bool synproxy_parse_options(const struct sk_buff *skb, unsigned int doff, 74 const struct tcphdr *th, 75 struct synproxy_options *opts); 76 unsigned int synproxy_options_size(const struct synproxy_options *opts); 77 void synproxy_build_options(struct tcphdr *th, 78 const struct synproxy_options *opts); 79 80 void synproxy_init_timestamp_cookie(const struct xt_synproxy_info *info, 81 struct synproxy_options *opts); 82 void synproxy_check_timestamp_cookie(struct synproxy_options *opts); 83 84 unsigned int synproxy_tstamp_adjust(struct sk_buff *skb, unsigned int protoff, 85 struct tcphdr *th, struct nf_conn *ct, 86 enum ip_conntrack_info ctinfo, 87 const struct nf_conn_synproxy *synproxy); 88 89 #endif /* _NF_CONNTRACK_SYNPROXY_H */ 90