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 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_defrag)(struct net *net, struct sk_buff *skb, u32 user);
  62         int (*br_fragment)(struct net *net, struct sock *sk,
  63                            struct sk_buff *skb,
  64                            struct nf_bridge_frag_data *data,
  65                            int (*output)(struct net *, struct sock *sk,
  66                                          const struct nf_bridge_frag_data *data,
  67                                          struct sk_buff *));
  68 #endif
  69 };
  70
  71 #ifdef CONFIG_NETFILTER
  72 #include <net/addrconf.h>
  73
  74 extern const struct nf_ipv6_ops __rcu *nf_ipv6_ops;
  75 static inline const struct nf_ipv6_ops *nf_get_ipv6_ops(void)
  76 {
  77         return rcu_dereference(nf_ipv6_ops);
  78 }
  79
  80 static inline int nf_ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
  81                                    const struct net_device *dev, int strict)
  82 {
  83 #if IS_MODULE(CONFIG_IPV6)
  84         const struct nf_ipv6_ops *v6_ops = nf_get_ipv6_ops();
  85
  86         if (!v6_ops)
  87                 return 1;
  88
  89         return v6_ops->chk_addr(net, addr, dev, strict);
  90 #elif IS_BUILTIN(CONFIG_IPV6)
  91         return ipv6_chk_addr(net, addr, dev, strict);
  92 #else
  93         return 1;
  94 #endif
  95 }
  96
  97 int __nf_ip6_route(struct net *net, struct dst_entry **dst,
  98                                struct flowi *fl, bool strict);
  99
 100 static inline int nf_ip6_route(struct net *net, struct dst_entry **dst,
 101                                struct flowi *fl, bool strict)
 102 {
 103 #if IS_MODULE(CONFIG_IPV6)
 104         const struct nf_ipv6_ops *v6ops = nf_get_ipv6_ops();
 105
 106         if (v6ops)
 107                 return v6ops->route(net, dst, fl, strict);
 108
 109         return -EHOSTUNREACH;
 110 #endif
 111 #if IS_BUILTIN(CONFIG_IPV6)
 112         return __nf_ip6_route(net, dst, fl, strict);
 113 #else
 114         return -EHOSTUNREACH;
 115 #endif
 116 }
 117
 118 #include <net/netfilter/ipv6/nf_defrag_ipv6.h>
 119
 120 static inline int nf_ipv6_br_defrag(struct net *net, struct sk_buff *skb,
 121                                     u32 user)
 122 {
 123 #if IS_MODULE(CONFIG_IPV6)
 124         const struct nf_ipv6_ops *v6_ops = nf_get_ipv6_ops();
 125
 126         if (!v6_ops)
 127                 return 1;
 128
 129         return v6_ops->br_defrag(net, skb, user);
 130 #elif IS_BUILTIN(CONFIG_IPV6)
 131         return nf_ct_frag6_gather(net, skb, user);
 132 #else
 133         return 1;
 134 #endif
 135 }
 136
 137 int br_ip6_fragment(struct net *net, struct sock *sk, struct sk_buff *skb,
 138                     struct nf_bridge_frag_data *data,
 139                     int (*output)(struct net *, struct sock *sk,
 140                                   const struct nf_bridge_frag_data *data,
 141                                   struct sk_buff *));
 142
 143 static inline int nf_br_ip6_fragment(struct net *net, struct sock *sk,
 144                                      struct sk_buff *skb,
 145                                      struct nf_bridge_frag_data *data,
 146                                      int (*output)(struct net *, struct sock *sk,
 147                                                    const struct nf_bridge_frag_data *data,
 148                                                    struct sk_buff *))
 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 1;
 155
 156         return v6_ops->br_fragment(net, sk, skb, data, output);
 157 #elif IS_BUILTIN(CONFIG_IPV6)
 158         return br_ip6_fragment(net, sk, skb, data, output);
 159 #else
 160         return 1;
 161 #endif
 162 }
 163
 164 int ip6_route_me_harder(struct net *net, struct sk_buff *skb);
 165
 166 static inline int nf_ip6_route_me_harder(struct net *net, struct sk_buff *skb)
 167 {
 168 #if IS_MODULE(CONFIG_IPV6)
 169         const struct nf_ipv6_ops *v6_ops = nf_get_ipv6_ops();
 170
 171         if (!v6_ops)
 172                 return -EHOSTUNREACH;
 173
 174         return v6_ops->route_me_harder(net, skb);
 175 #elif IS_BUILTIN(CONFIG_IPV6)
 176         return ip6_route_me_harder(net, skb);
 177 #else
 178         return -EHOSTUNREACH;
 179 #endif
 180 }
 181
 182 static inline u32 nf_ipv6_cookie_init_sequence(const struct ipv6hdr *iph,
 183                                                const struct tcphdr *th,
 184                                                u16 *mssp)
 185 {
 186 #if IS_ENABLED(CONFIG_SYN_COOKIES)
 187 #if IS_MODULE(CONFIG_IPV6)
 188         const struct nf_ipv6_ops *v6_ops = nf_get_ipv6_ops();
 189
 190         if (v6_ops)
 191                 return v6_ops->cookie_init_sequence(iph, th, mssp);
 192 #elif IS_BUILTIN(CONFIG_IPV6)
 193         return __cookie_v6_init_sequence(iph, th, mssp);
 194 #endif
 195 #endif
 196         return 0;
 197 }
 198
 199 static inline int nf_cookie_v6_check(const struct ipv6hdr *iph,
 200                                      const struct tcphdr *th, __u32 cookie)
 201 {
 202 #if IS_ENABLED(CONFIG_SYN_COOKIES)
 203 #if IS_MODULE(CONFIG_IPV6)
 204         const struct nf_ipv6_ops *v6_ops = nf_get_ipv6_ops();
 205
 206         if (v6_ops)
 207                 return v6_ops->cookie_v6_check(iph, th, cookie);
 208 #elif IS_BUILTIN(CONFIG_IPV6)
 209         return __cookie_v6_check(iph, th, cookie);
 210 #endif
 211 #endif
 212         return 0;
 213 }
 214
 215 __sum16 nf_ip6_checksum(struct sk_buff *skb, unsigned int hook,
 216                         unsigned int dataoff, u_int8_t protocol);
 217
 218 int ipv6_netfilter_init(void);
 219 void ipv6_netfilter_fini(void);
 220
 221 #else /* CONFIG_NETFILTER */
 222 static inline int ipv6_netfilter_init(void) { return 0; }
 223 static inline void ipv6_netfilter_fini(void) { return; }
 224 static inline const struct nf_ipv6_ops *nf_get_ipv6_ops(void) { return NULL; }
 225 #endif /* CONFIG_NETFILTER */
 226
 227 #endif /*__LINUX_IP6_NETFILTER_H*/