include/net/ndisc.h

   1 #ifndef _NDISC_H
   2 #define _NDISC_H
   3
   4 /*
   5  *      ICMP codes for neighbour discovery messages
   6  */
   7
   8 #define NDISC_ROUTER_SOLICITATION       133
   9 #define NDISC_ROUTER_ADVERTISEMENT      134
  10 #define NDISC_NEIGHBOUR_SOLICITATION    135
  11 #define NDISC_NEIGHBOUR_ADVERTISEMENT   136
  12 #define NDISC_REDIRECT                  137
  13
  14 /*
  15  * Router type: cross-layer information from link-layer to
  16  * IPv6 layer reported by certain link types (e.g., RFC4214).
  17  */
  18 #define NDISC_NODETYPE_UNSPEC           0       /* unspecified (default) */
  19 #define NDISC_NODETYPE_HOST             1       /* host or unauthorized router */
  20 #define NDISC_NODETYPE_NODEFAULT        2       /* non-default router */
  21 #define NDISC_NODETYPE_DEFAULT          3       /* default router */
  22
  23 /*
  24  *      ndisc options
  25  */
  26
  27 enum {
  28         __ND_OPT_PREFIX_INFO_END = 0,
  29         ND_OPT_SOURCE_LL_ADDR = 1,      /* RFC2461 */
  30         ND_OPT_TARGET_LL_ADDR = 2,      /* RFC2461 */
  31         ND_OPT_PREFIX_INFO = 3,         /* RFC2461 */
  32         ND_OPT_REDIRECT_HDR = 4,        /* RFC2461 */
  33         ND_OPT_MTU = 5,                 /* RFC2461 */
  34         __ND_OPT_ARRAY_MAX,
  35         ND_OPT_ROUTE_INFO = 24,         /* RFC4191 */
  36         ND_OPT_RDNSS = 25,              /* RFC5006 */
  37         ND_OPT_DNSSL = 31,              /* RFC6106 */
  38         __ND_OPT_MAX
  39 };
  40
  41 #define MAX_RTR_SOLICITATION_DELAY      HZ
  42
  43 #define ND_REACHABLE_TIME               (30*HZ)
  44 #define ND_RETRANS_TIMER                HZ
  45
  46 #include <linux/compiler.h>
  47 #include <linux/icmpv6.h>
  48 #include <linux/in6.h>
  49 #include <linux/types.h>
  50 #include <linux/if_arp.h>
  51 #include <linux/netdevice.h>
  52 #include <linux/hash.h>
  53
  54 #include <net/neighbour.h>
  55
  56 struct ctl_table;
  57 struct inet6_dev;
  58 struct net_device;
  59 struct net_proto_family;
  60 struct sk_buff;
  61
  62 extern struct neigh_table nd_tbl;
  63
  64 struct nd_msg {
  65         struct icmp6hdr icmph;
  66         struct in6_addr target;
  67         __u8            opt[0];
  68 };
  69
  70 struct rs_msg {
  71         struct icmp6hdr icmph;
  72         __u8            opt[0];
  73 };
  74
  75 struct ra_msg {
  76         struct icmp6hdr         icmph;
  77         __be32                  reachable_time;
  78         __be32                  retrans_timer;
  79 };
  80
  81 struct rd_msg {
  82         struct icmp6hdr icmph;
  83         struct in6_addr target;
  84         struct in6_addr dest;
  85         __u8            opt[0];
  86 };
  87
  88 struct nd_opt_hdr {
  89         __u8            nd_opt_type;
  90         __u8            nd_opt_len;
  91 } __packed;
  92
  93 /* ND options */
  94 struct ndisc_options {
  95         struct nd_opt_hdr *nd_opt_array[__ND_OPT_ARRAY_MAX];
  96 #ifdef CONFIG_IPV6_ROUTE_INFO
  97         struct nd_opt_hdr *nd_opts_ri;
  98         struct nd_opt_hdr *nd_opts_ri_end;
  99 #endif
 100         struct nd_opt_hdr *nd_useropts;
 101         struct nd_opt_hdr *nd_useropts_end;
 102 };
 103
 104 #define nd_opts_src_lladdr      nd_opt_array[ND_OPT_SOURCE_LL_ADDR]
 105 #define nd_opts_tgt_lladdr      nd_opt_array[ND_OPT_TARGET_LL_ADDR]
 106 #define nd_opts_pi              nd_opt_array[ND_OPT_PREFIX_INFO]
 107 #define nd_opts_pi_end          nd_opt_array[__ND_OPT_PREFIX_INFO_END]
 108 #define nd_opts_rh              nd_opt_array[ND_OPT_REDIRECT_HDR]
 109 #define nd_opts_mtu             nd_opt_array[ND_OPT_MTU]
 110
 111 #define NDISC_OPT_SPACE(len) (((len)+2+7)&~7)
 112
 113 extern struct ndisc_options *ndisc_parse_options(u8 *opt, int opt_len,
 114                                                  struct ndisc_options *ndopts);
 115
 116 /*
 117  * Return the padding between the option length and the start of the
 118  * link addr.  Currently only IP-over-InfiniBand needs this, although
 119  * if RFC 3831 IPv6-over-Fibre Channel is ever implemented it may
 120  * also need a pad of 2.
 121  */
 122 static int ndisc_addr_option_pad(unsigned short type)
 123 {
 124         switch (type) {
 125         case ARPHRD_INFINIBAND: return 2;
 126         default:                return 0;
 127         }
 128 }
 129
 130 static inline int ndisc_opt_addr_space(struct net_device *dev)
 131 {
 132         return NDISC_OPT_SPACE(dev->addr_len +
 133                                ndisc_addr_option_pad(dev->type));
 134 }
 135
 136 static inline u8 *ndisc_opt_addr_data(struct nd_opt_hdr *p,
 137                                       struct net_device *dev)
 138 {
 139         u8 *lladdr = (u8 *)(p + 1);
 140         int lladdrlen = p->nd_opt_len << 3;
 141         int prepad = ndisc_addr_option_pad(dev->type);
 142         if (lladdrlen != ndisc_opt_addr_space(dev))
 143                 return NULL;
 144         return lladdr + prepad;
 145 }
 146
 147 static inline u32 ndisc_hashfn(const void *pkey, const struct net_device *dev, __u32 *hash_rnd)
 148 {
 149         const u32 *p32 = pkey;
 150
 151         return (((p32[0] ^ hash32_ptr(dev)) * hash_rnd[0]) +
 152                 (p32[1] * hash_rnd[1]) +
 153                 (p32[2] * hash_rnd[2]) +
 154                 (p32[3] * hash_rnd[3]));
 155 }
 156
 157 static inline struct neighbour *__ipv6_neigh_lookup_noref(struct net_device *dev, const void *pkey)
 158 {
 159         struct neigh_hash_table *nht;
 160         const u32 *p32 = pkey;
 161         struct neighbour *n;
 162         u32 hash_val;
 163
 164         nht = rcu_dereference_bh(nd_tbl.nht);
 165         hash_val = ndisc_hashfn(pkey, dev, nht->hash_rnd) >> (32 - nht->hash_shift);
 166         for (n = rcu_dereference_bh(nht->hash_buckets[hash_val]);
 167              n != NULL;
 168              n = rcu_dereference_bh(n->next)) {
 169                 u32 *n32 = (u32 *) n->primary_key;
 170                 if (n->dev == dev &&
 171                     ((n32[0] ^ p32[0]) | (n32[1] ^ p32[1]) |
 172                      (n32[2] ^ p32[2]) | (n32[3] ^ p32[3])) == 0)
 173                         return n;
 174         }
 175
 176         return NULL;
 177 }
 178
 179 static inline struct neighbour *__ipv6_neigh_lookup(struct net_device *dev, const void *pkey)
 180 {
 181         struct neighbour *n;
 182
 183         rcu_read_lock_bh();
 184         n = __ipv6_neigh_lookup_noref(dev, pkey);
 185         if (n && !atomic_inc_not_zero(&n->refcnt))
 186                 n = NULL;
 187         rcu_read_unlock_bh();
 188
 189         return n;
 190 }
 191
 192 extern int                      ndisc_init(void);
 193
 194 extern void                     ndisc_cleanup(void);
 195
 196 extern int                      ndisc_rcv(struct sk_buff *skb);
 197
 198 extern void                     ndisc_send_ns(struct net_device *dev,
 199                                               struct neighbour *neigh,
 200                                               const struct in6_addr *solicit,
 201                                               const struct in6_addr *daddr,
 202                                               const struct in6_addr *saddr);
 203
 204 extern void                     ndisc_send_rs(struct net_device *dev,
 205                                               const struct in6_addr *saddr,
 206                                               const struct in6_addr *daddr);
 207
 208 extern void                     ndisc_send_redirect(struct sk_buff *skb,
 209                                                     const struct in6_addr *target);
 210
 211 extern int                      ndisc_mc_map(const struct in6_addr *addr, char *buf,
 212                                              struct net_device *dev, int dir);
 213
 214
 215 /*
 216  *      IGMP
 217  */
 218 extern int                      igmp6_init(void);
 219
 220 extern void                     igmp6_cleanup(void);
 221
 222 extern int                      igmp6_event_query(struct sk_buff *skb);
 223
 224 extern int                      igmp6_event_report(struct sk_buff *skb);
 225
 226
 227 #ifdef CONFIG_SYSCTL
 228 extern int                      ndisc_ifinfo_sysctl_change(struct ctl_table *ctl,
 229                                                            int write,
 230                                                            void __user *buffer,
 231                                                            size_t *lenp,
 232                                                            loff_t *ppos);
 233 int ndisc_ifinfo_sysctl_strategy(ctl_table *ctl,
 234                                  void __user *oldval, size_t __user *oldlenp,
 235                                  void __user *newval, size_t newlen);
 236 #endif
 237
 238 extern void                     inet6_ifinfo_notify(int event,
 239                                                     struct inet6_dev *idev);
 240
 241 #endif