include/net/ip6_route.h

   1 #ifndef _NET_IP6_ROUTE_H
   2 #define _NET_IP6_ROUTE_H
   3
   4 struct route_info {
   5         __u8                    type;
   6         __u8                    length;
   7         __u8                    prefix_len;
   8 #if defined(__BIG_ENDIAN_BITFIELD)
   9         __u8                    reserved_h:3,
  10                                 route_pref:2,
  11                                 reserved_l:3;
  12 #elif defined(__LITTLE_ENDIAN_BITFIELD)
  13         __u8                    reserved_l:3,
  14                                 route_pref:2,
  15                                 reserved_h:3;
  16 #endif
  17         __be32                  lifetime;
  18         __u8                    prefix[0];      /* 0,8 or 16 */
  19 };
  20
  21 #include <net/addrconf.h>
  22 #include <net/flow.h>
  23 #include <net/ip6_fib.h>
  24 #include <net/sock.h>
  25 #include <net/lwtunnel.h>
  26 #include <linux/ip.h>
  27 #include <linux/ipv6.h>
  28 #include <linux/route.h>
  29
  30 #define RT6_LOOKUP_F_IFACE              0x00000001
  31 #define RT6_LOOKUP_F_REACHABLE          0x00000002
  32 #define RT6_LOOKUP_F_HAS_SADDR          0x00000004
  33 #define RT6_LOOKUP_F_SRCPREF_TMP        0x00000008
  34 #define RT6_LOOKUP_F_SRCPREF_PUBLIC     0x00000010
  35 #define RT6_LOOKUP_F_SRCPREF_COA        0x00000020
  36 #define RT6_LOOKUP_F_IGNORE_LINKSTATE   0x00000040
  37
  38 /* We do not (yet ?) support IPv6 jumbograms (RFC 2675)
  39  * Unlike IPv4, hdr->seg_len doesn't include the IPv6 header
  40  */
  41 #define IP6_MAX_MTU (0xFFFF + sizeof(struct ipv6hdr))
  42
  43 /*
  44  * rt6_srcprefs2flags() and rt6_flags2srcprefs() translate
  45  * between IPV6_ADDR_PREFERENCES socket option values
  46  *      IPV6_PREFER_SRC_TMP    = 0x1
  47  *      IPV6_PREFER_SRC_PUBLIC = 0x2
  48  *      IPV6_PREFER_SRC_COA    = 0x4
  49  * and above RT6_LOOKUP_F_SRCPREF_xxx flags.
  50  */
  51 static inline int rt6_srcprefs2flags(unsigned int srcprefs)
  52 {
  53         /* No need to bitmask because srcprefs have only 3 bits. */
  54         return srcprefs << 3;
  55 }
  56
  57 static inline unsigned int rt6_flags2srcprefs(int flags)
  58 {
  59         return (flags >> 3) & 7;
  60 }
  61
  62 static inline bool rt6_need_strict(const struct in6_addr *daddr)
  63 {
  64         return ipv6_addr_type(daddr) &
  65                 (IPV6_ADDR_MULTICAST | IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK);
  66 }
  67
  68 void ip6_route_input(struct sk_buff *skb);
  69 struct dst_entry *ip6_route_input_lookup(struct net *net,
  70                                          struct net_device *dev,
  71                                          struct flowi6 *fl6, int flags);
  72
  73 struct dst_entry *ip6_route_output_flags(struct net *net, const struct sock *sk,
  74                                          struct flowi6 *fl6, int flags);
  75
  76 static inline struct dst_entry *ip6_route_output(struct net *net,
  77                                                  const struct sock *sk,
  78                                                  struct flowi6 *fl6)
  79 {
  80         return ip6_route_output_flags(net, sk, fl6, 0);
  81 }
  82
  83 struct dst_entry *ip6_route_lookup(struct net *net, struct flowi6 *fl6,
  84                                    int flags);
  85 struct rt6_info *ip6_pol_route(struct net *net, struct fib6_table *table,
  86                                int ifindex, struct flowi6 *fl6, int flags);
  87
  88 void ip6_route_init_special_entries(void);
  89 int ip6_route_init(void);
  90 void ip6_route_cleanup(void);
  91
  92 int ipv6_route_ioctl(struct net *net, unsigned int cmd, void __user *arg);
  93
  94 int ip6_route_add(struct fib6_config *cfg, struct netlink_ext_ack *extack);
  95 int ip6_ins_rt(struct rt6_info *);
  96 int ip6_del_rt(struct rt6_info *);
  97
  98 static inline int ip6_route_get_saddr(struct net *net, struct rt6_info *rt,
  99                                       const struct in6_addr *daddr,
 100                                       unsigned int prefs,
 101                                       struct in6_addr *saddr)
 102 {
 103         struct inet6_dev *idev =
 104                         rt ? ip6_dst_idev((struct dst_entry *)rt) : NULL;
 105         int err = 0;
 106
 107         if (rt && rt->rt6i_prefsrc.plen)
 108                 *saddr = rt->rt6i_prefsrc.addr;
 109         else
 110                 err = ipv6_dev_get_saddr(net, idev ? idev->dev : NULL,
 111                                          daddr, prefs, saddr);
 112
 113         return err;
 114 }
 115
 116 struct rt6_info *rt6_lookup(struct net *net, const struct in6_addr *daddr,
 117                             const struct in6_addr *saddr, int oif, int flags);
 118
 119 struct dst_entry *icmp6_dst_alloc(struct net_device *dev, struct flowi6 *fl6);
 120
 121 void fib6_force_start_gc(struct net *net);
 122
 123 struct rt6_info *addrconf_dst_alloc(struct inet6_dev *idev,
 124                                     const struct in6_addr *addr, bool anycast);
 125
 126 struct rt6_info *ip6_dst_alloc(struct net *net, struct net_device *dev,
 127                                int flags);
 128
 129 /*
 130  *      support functions for ND
 131  *
 132  */
 133 struct rt6_info *rt6_get_dflt_router(const struct in6_addr *addr,
 134                                      struct net_device *dev);
 135 struct rt6_info *rt6_add_dflt_router(const struct in6_addr *gwaddr,
 136                                      struct net_device *dev, unsigned int pref);
 137
 138 void rt6_purge_dflt_routers(struct net *net);
 139
 140 int rt6_route_rcv(struct net_device *dev, u8 *opt, int len,
 141                   const struct in6_addr *gwaddr);
 142
 143 void ip6_update_pmtu(struct sk_buff *skb, struct net *net, __be32 mtu, int oif,
 144                      u32 mark, kuid_t uid);
 145 void ip6_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, __be32 mtu);
 146 void ip6_redirect(struct sk_buff *skb, struct net *net, int oif, u32 mark,
 147                   kuid_t uid);
 148 void ip6_redirect_no_header(struct sk_buff *skb, struct net *net, int oif,
 149                             u32 mark);
 150 void ip6_sk_redirect(struct sk_buff *skb, struct sock *sk);
 151
 152 struct netlink_callback;
 153
 154 struct rt6_rtnl_dump_arg {
 155         struct sk_buff *skb;
 156         struct netlink_callback *cb;
 157         struct net *net;
 158 };
 159
 160 int rt6_dump_route(struct rt6_info *rt, void *p_arg);
 161 void rt6_ifdown(struct net *net, struct net_device *dev);
 162 void rt6_mtu_change(struct net_device *dev, unsigned int mtu);
 163 void rt6_remove_prefsrc(struct inet6_ifaddr *ifp);
 164 void rt6_clean_tohost(struct net *net, struct in6_addr *gateway);
 165
 166
 167 /*
 168  *      Store a destination cache entry in a socket
 169  */
 170 static inline void ip6_dst_store(struct sock *sk, struct dst_entry *dst,
 171                                  const struct in6_addr *daddr,
 172                                  const struct in6_addr *saddr)
 173 {
 174         struct ipv6_pinfo *np = inet6_sk(sk);
 175
 176         np->dst_cookie = rt6_get_cookie((struct rt6_info *)dst);
 177         sk_setup_caps(sk, dst);
 178         np->daddr_cache = daddr;
 179 #ifdef CONFIG_IPV6_SUBTREES
 180         np->saddr_cache = saddr;
 181 #endif
 182 }
 183
 184 static inline bool ipv6_unicast_destination(const struct sk_buff *skb)
 185 {
 186         struct rt6_info *rt = (struct rt6_info *) skb_dst(skb);
 187
 188         return rt->rt6i_flags & RTF_LOCAL;
 189 }
 190
 191 static inline bool ipv6_anycast_destination(const struct dst_entry *dst,
 192                                             const struct in6_addr *daddr)
 193 {
 194         struct rt6_info *rt = (struct rt6_info *)dst;
 195
 196         return rt->rt6i_flags & RTF_ANYCAST ||
 197                 (rt->rt6i_dst.plen != 128 &&
 198                  ipv6_addr_equal(&rt->rt6i_dst.addr, daddr));
 199 }
 200
 201 int ip6_fragment(struct net *net, struct sock *sk, struct sk_buff *skb,
 202                  int (*output)(struct net *, struct sock *, struct sk_buff *));
 203
 204 static inline int ip6_skb_dst_mtu(struct sk_buff *skb)
 205 {
 206         struct ipv6_pinfo *np = skb->sk && !dev_recursion_level() ?
 207                                 inet6_sk(skb->sk) : NULL;
 208
 209         return (np && np->pmtudisc >= IPV6_PMTUDISC_PROBE) ?
 210                skb_dst(skb)->dev->mtu : dst_mtu(skb_dst(skb));
 211 }
 212
 213 static inline bool ip6_sk_accept_pmtu(const struct sock *sk)
 214 {
 215         return inet6_sk(sk)->pmtudisc != IPV6_PMTUDISC_INTERFACE &&
 216                inet6_sk(sk)->pmtudisc != IPV6_PMTUDISC_OMIT;
 217 }
 218
 219 static inline bool ip6_sk_ignore_df(const struct sock *sk)
 220 {
 221         return inet6_sk(sk)->pmtudisc < IPV6_PMTUDISC_DO ||
 222                inet6_sk(sk)->pmtudisc == IPV6_PMTUDISC_OMIT;
 223 }
 224
 225 static inline struct in6_addr *rt6_nexthop(struct rt6_info *rt,
 226                                            struct in6_addr *daddr)
 227 {
 228         if (rt->rt6i_flags & RTF_GATEWAY)
 229                 return &rt->rt6i_gateway;
 230         else if (unlikely(rt->rt6i_flags & RTF_CACHE))
 231                 return &rt->rt6i_dst.addr;
 232         else
 233                 return daddr;
 234 }
 235
 236 static inline bool rt6_duplicate_nexthop(struct rt6_info *a, struct rt6_info *b)
 237 {
 238         return a->dst.dev == b->dst.dev &&
 239                a->rt6i_idev == b->rt6i_idev &&
 240                ipv6_addr_equal(&a->rt6i_gateway, &b->rt6i_gateway) &&
 241                !lwtunnel_cmp_encap(a->dst.lwtstate, b->dst.lwtstate);
 242 }
 243 #endif