1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef _NF_SYNPROXY_SHARED_H 3 #define _NF_SYNPROXY_SHARED_H 4 5 #include <linux/module.h> 6 #include <linux/skbuff.h> 7 #include <net/ip6_checksum.h> 8 #include <net/ip6_route.h> 9 #include <net/tcp.h> 10 11 #include <net/netfilter/nf_conntrack_seqadj.h> 12 #include <net/netfilter/nf_conntrack_synproxy.h> 13 14 struct synproxy_stats { 15 unsigned int syn_received; 16 unsigned int cookie_invalid; 17 unsigned int cookie_valid; 18 unsigned int cookie_retrans; 19 unsigned int conn_reopened; 20 }; 21 22 struct synproxy_net { 23 struct nf_conn *tmpl; 24 struct synproxy_stats __percpu *stats; 25 unsigned int hook_ref4; 26 unsigned int hook_ref6; 27 }; 28 29 extern unsigned int synproxy_net_id; 30 static inline struct synproxy_net *synproxy_pernet(struct net *net) 31 { 32 return net_generic(net, synproxy_net_id); 33 } 34 35 struct synproxy_options { 36 u8 options; 37 u8 wscale; 38 u16 mss_option; 39 u16 mss_encode; 40 u32 tsval; 41 u32 tsecr; 42 }; 43 44 struct nf_synproxy_info; 45 bool synproxy_parse_options(const struct sk_buff *skb, unsigned int doff, 46 const struct tcphdr *th, 47 struct synproxy_options *opts); 48 49 void synproxy_init_timestamp_cookie(const struct nf_synproxy_info *info, 50 struct synproxy_options *opts); 51 52 void synproxy_send_client_synack(struct net *net, const struct sk_buff *skb, 53 const struct tcphdr *th, 54 const struct synproxy_options *opts); 55 56 bool synproxy_recv_client_ack(struct net *net, 57 const struct sk_buff *skb, 58 const struct tcphdr *th, 59 struct synproxy_options *opts, u32 recv_seq); 60 61 struct nf_hook_state; 62 63 unsigned int ipv4_synproxy_hook(void *priv, struct sk_buff *skb, 64 const struct nf_hook_state *nhs); 65 int nf_synproxy_ipv4_init(struct synproxy_net *snet, struct net *net); 66 void nf_synproxy_ipv4_fini(struct synproxy_net *snet, struct net *net); 67 68 #if IS_ENABLED(CONFIG_IPV6) 69 void synproxy_send_client_synack_ipv6(struct net *net, 70 const struct sk_buff *skb, 71 const struct tcphdr *th, 72 const struct synproxy_options *opts); 73 74 bool synproxy_recv_client_ack_ipv6(struct net *net, const struct sk_buff *skb, 75 const struct tcphdr *th, 76 struct synproxy_options *opts, u32 recv_seq); 77 78 unsigned int ipv6_synproxy_hook(void *priv, struct sk_buff *skb, 79 const struct nf_hook_state *nhs); 80 int nf_synproxy_ipv6_init(struct synproxy_net *snet, struct net *net); 81 void nf_synproxy_ipv6_fini(struct synproxy_net *snet, struct net *net); 82 #else 83 static inline int 84 nf_synproxy_ipv6_init(struct synproxy_net *snet, struct net *net) { return 0; } 85 static inline void 86 nf_synproxy_ipv6_fini(struct synproxy_net *snet, struct net *net) {}; 87 #endif /* CONFIG_IPV6 */ 88 89 #endif /* _NF_SYNPROXY_SHARED_H */ 90