include/linux/netfilter_ipv6.h

   1 /* IPv6-specific defines for netfilter.
   2  * (C)1998 Rusty Russell -- This code is GPL.
   3  * (C)1999 David Jeffery
   4  *   this header was blatantly ripped from netfilter_ipv4.h
   5  *   it's amazing what adding a bunch of 6s can do =8^)
   6  */
   7 #ifndef __LINUX_IP6_NETFILTER_H
   8 #define __LINUX_IP6_NETFILTER_H
   9
  10 #include <uapi/linux/netfilter_ipv6.h>
  11 #include <net/tcp.h>
  12
  13 /* Check for an extension */
  14 static inline int
  15 nf_ip6_ext_hdr(u8 nexthdr)
  16 {       return (nexthdr == IPPROTO_HOPOPTS) ||
  17                (nexthdr == IPPROTO_ROUTING) ||
  18                (nexthdr == IPPROTO_FRAGMENT) ||
  19                (nexthdr == IPPROTO_ESP) ||
  20                (nexthdr == IPPROTO_AH) ||
  21                (nexthdr == IPPROTO_NONE) ||
  22                (nexthdr == IPPROTO_DSTOPTS);
  23 }
  24
  25 /* Extra routing may needed on local out, as the QUEUE target never returns
  26  * control to the table.
  27  */
  28 struct ip6_rt_info {
  29         struct in6_addr daddr;
  30         struct in6_addr saddr;
  31         u_int32_t mark;
  32 };
  33
  34 struct nf_queue_entry;
  35 struct nf_bridge_frag_data;
  36
  37 /*
  38  * Hook functions for ipv6 to allow xt_* modules to be built-in even
  39  * if IPv6 is a module.
  40  */
  41 struct nf_ipv6_ops {
  42 #if IS_MODULE(CONFIG_IPV6)
  43         int (*chk_addr)(struct net *net, const struct in6_addr *addr,
  44                         const struct net_device *dev, int strict);
  45         int (*route_me_harder)(struct net *net, struct sock *sk, struct sk_buff *skb);
  46         int (*dev_get_saddr)(struct net *net, const struct net_device *dev,
  47                        const struct in6_addr *daddr, unsigned int srcprefs,
  48                        struct in6_addr *saddr);
  49         int (*route)(struct net *net, struct dst_entry **dst, struct flowi *fl,
  50                      bool strict);
  51         u32 (*cookie_init_sequence)(const struct ipv6hdr *iph,
  52                                     const struct tcphdr *th, u16 *mssp);
  53         int (*cookie_v6_check)(const struct ipv6hdr *iph,
  54                                const struct tcphdr *th, __u32 cookie);
  55 #endif
  56         void (*route_input)(struct sk_buff *skb);
  57         int (*fragment)(struct net *net, struct sock *sk, struct sk_buff *skb,
  58                         int (*output)(struct net *, struct sock *, struct sk_buff *));
  59         int (*reroute)(struct sk_buff *skb, const struct nf_queue_entry *entry);
  60 #if IS_MODULE(CONFIG_IPV6)
  61         int (*br_fragment)(struct net *net, struct sock *sk,
  62                            struct sk_buff *skb,
  63                            struct nf_bridge_frag_data *data,
  64                            int (*output)(struct net *, struct sock *sk,
  65                                          const struct nf_bridge_frag_data *data,
  66                                          struct sk_buff *));
  67 #endif
  68 };
  69
  70 #ifdef CONFIG_NETFILTER
  71 #include <net/addrconf.h>
  72
  73 extern const struct nf_ipv6_ops __rcu *nf_ipv6_ops;
  74 static inline const struct nf_ipv6_ops *nf_get_ipv6_ops(void)
  75 {
  76         return rcu_dereference(nf_ipv6_ops);
  77 }
  78
  79 static inline int nf_ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
  80                                    const struct net_device *dev, int strict)
  81 {
  82 #if IS_MODULE(CONFIG_IPV6)
  83         const struct nf_ipv6_ops *v6_ops = nf_get_ipv6_ops();
  84
  85         if (!v6_ops)
  86                 return 1;
  87
  88         return v6_ops->chk_addr(net, addr, dev, strict);
  89 #elif IS_BUILTIN(CONFIG_IPV6)
  90         return ipv6_chk_addr(net, addr, dev, strict);
  91 #else
  92         return 1;
  93 #endif
  94 }
  95
  96 int __nf_ip6_route(struct net *net, struct dst_entry **dst,
  97                                struct flowi *fl, bool strict);
  98
  99 static inline int nf_ip6_route(struct net *net, struct dst_entry **dst,
 100                                struct flowi *fl, bool strict)
 101 {
 102 #if IS_MODULE(CONFIG_IPV6)
 103         const struct nf_ipv6_ops *v6ops = nf_get_ipv6_ops();
 104
 105         if (v6ops)
 106                 return v6ops->route(net, dst, fl, strict);
 107
 108         return -EHOSTUNREACH;
 109 #endif
 110 #if IS_BUILTIN(CONFIG_IPV6)
 111         return __nf_ip6_route(net, dst, fl, strict);
 112 #else
 113         return -EHOSTUNREACH;
 114 #endif
 115 }
 116
 117 #include <net/netfilter/ipv6/nf_defrag_ipv6.h>
 118
 119 int br_ip6_fragment(struct net *net, struct sock *sk, struct sk_buff *skb,
 120                     struct nf_bridge_frag_data *data,
 121                     int (*output)(struct net *, struct sock *sk,
 122                                   const struct nf_bridge_frag_data *data,
 123                                   struct sk_buff *));
 124
 125 static inline int nf_br_ip6_fragment(struct net *net, struct sock *sk,
 126                                      struct sk_buff *skb,
 127                                      struct nf_bridge_frag_data *data,
 128                                      int (*output)(struct net *, struct sock *sk,
 129                                                    const struct nf_bridge_frag_data *data,
 130                                                    struct sk_buff *))
 131 {
 132 #if IS_MODULE(CONFIG_IPV6)
 133         const struct nf_ipv6_ops *v6_ops = nf_get_ipv6_ops();
 134
 135         if (!v6_ops)
 136                 return 1;
 137
 138         return v6_ops->br_fragment(net, sk, skb, data, output);
 139 #elif IS_BUILTIN(CONFIG_IPV6)
 140         return br_ip6_fragment(net, sk, skb, data, output);
 141 #else
 142         return 1;
 143 #endif
 144 }
 145
 146 int ip6_route_me_harder(struct net *net, struct sock *sk, struct sk_buff *skb);
 147
 148 static inline int nf_ip6_route_me_harder(struct net *net, struct sock *sk, struct sk_buff *skb)
 149 {
 150 #if IS_MODULE(CONFIG_IPV6)
 151         const struct nf_ipv6_ops *v6_ops = nf_get_ipv6_ops();
 152
 153         if (!v6_ops)
 154                 return -EHOSTUNREACH;
 155
 156         return v6_ops->route_me_harder(net, sk, skb);
 157 #elif IS_BUILTIN(CONFIG_IPV6)
 158         return ip6_route_me_harder(net, sk, skb);
 159 #else
 160         return -EHOSTUNREACH;
 161 #endif
 162 }
 163
 164 static inline u32 nf_ipv6_cookie_init_sequence(const struct ipv6hdr *iph,
 165                                                const struct tcphdr *th,
 166                                                u16 *mssp)
 167 {
 168 #if IS_ENABLED(CONFIG_SYN_COOKIES)
 169 #if IS_MODULE(CONFIG_IPV6)
 170         const struct nf_ipv6_ops *v6_ops = nf_get_ipv6_ops();
 171
 172         if (v6_ops)
 173                 return v6_ops->cookie_init_sequence(iph, th, mssp);
 174 #elif IS_BUILTIN(CONFIG_IPV6)
 175         return __cookie_v6_init_sequence(iph, th, mssp);
 176 #endif
 177 #endif
 178         return 0;
 179 }
 180
 181 static inline int nf_cookie_v6_check(const struct ipv6hdr *iph,
 182                                      const struct tcphdr *th, __u32 cookie)
 183 {
 184 #if IS_ENABLED(CONFIG_SYN_COOKIES)
 185 #if IS_MODULE(CONFIG_IPV6)
 186         const struct nf_ipv6_ops *v6_ops = nf_get_ipv6_ops();
 187
 188         if (v6_ops)
 189                 return v6_ops->cookie_v6_check(iph, th, cookie);
 190 #elif IS_BUILTIN(CONFIG_IPV6)
 191         return __cookie_v6_check(iph, th, cookie);
 192 #endif
 193 #endif
 194         return 0;
 195 }
 196
 197 __sum16 nf_ip6_checksum(struct sk_buff *skb, unsigned int hook,
 198                         unsigned int dataoff, u_int8_t protocol);
 199
 200 int ipv6_netfilter_init(void);
 201 void ipv6_netfilter_fini(void);
 202
 203 #else /* CONFIG_NETFILTER */
 204 static inline int ipv6_netfilter_init(void) { return 0; }
 205 static inline void ipv6_netfilter_fini(void) { return; }
 206 static inline const struct nf_ipv6_ops *nf_get_ipv6_ops(void) { return NULL; }
 207 #endif /* CONFIG_NETFILTER */
 208
 209 #endif /*__LINUX_IP6_NETFILTER_H*/