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 nd_opt_hdr {
  82         __u8            nd_opt_type;
  83         __u8            nd_opt_len;
  84 } __packed;
  85
  86 /* ND options */
  87 struct ndisc_options {
  88         struct nd_opt_hdr *nd_opt_array[__ND_OPT_ARRAY_MAX];
  89 #ifdef CONFIG_IPV6_ROUTE_INFO
  90         struct nd_opt_hdr *nd_opts_ri;
  91         struct nd_opt_hdr *nd_opts_ri_end;
  92 #endif
  93         struct nd_opt_hdr *nd_useropts;
  94         struct nd_opt_hdr *nd_useropts_end;
  95 };
  96
  97 #define nd_opts_src_lladdr      nd_opt_array[ND_OPT_SOURCE_LL_ADDR]
  98 #define nd_opts_tgt_lladdr      nd_opt_array[ND_OPT_TARGET_LL_ADDR]
  99 #define nd_opts_pi              nd_opt_array[ND_OPT_PREFIX_INFO]
 100 #define nd_opts_pi_end          nd_opt_array[__ND_OPT_PREFIX_INFO_END]
 101 #define nd_opts_rh              nd_opt_array[ND_OPT_REDIRECT_HDR]
 102 #define nd_opts_mtu             nd_opt_array[ND_OPT_MTU]
 103
 104 #define NDISC_OPT_SPACE(len) (((len)+2+7)&~7)
 105
 106 extern struct ndisc_options *ndisc_parse_options(u8 *opt, int opt_len,
 107                                                  struct ndisc_options *ndopts);
 108
 109 /*
 110  * Return the padding between the option length and the start of the
 111  * link addr.  Currently only IP-over-InfiniBand needs this, although
 112  * if RFC 3831 IPv6-over-Fibre Channel is ever implemented it may
 113  * also need a pad of 2.
 114  */
 115 static int ndisc_addr_option_pad(unsigned short type)
 116 {
 117         switch (type) {
 118         case ARPHRD_INFINIBAND: return 2;
 119         default:                return 0;
 120         }
 121 }
 122
 123 static inline u8 *ndisc_opt_addr_data(struct nd_opt_hdr *p,
 124                                       struct net_device *dev)
 125 {
 126         u8 *lladdr = (u8 *)(p + 1);
 127         int lladdrlen = p->nd_opt_len << 3;
 128         int prepad = ndisc_addr_option_pad(dev->type);
 129         if (lladdrlen != NDISC_OPT_SPACE(dev->addr_len + prepad))
 130                 return NULL;
 131         return lladdr + prepad;
 132 }
 133
 134 static inline u32 ndisc_hashfn(const void *pkey, const struct net_device *dev, __u32 *hash_rnd)
 135 {
 136         const u32 *p32 = pkey;
 137
 138         return (((p32[0] ^ hash32_ptr(dev)) * hash_rnd[0]) +
 139                 (p32[1] * hash_rnd[1]) +
 140                 (p32[2] * hash_rnd[2]) +
 141                 (p32[3] * hash_rnd[3]));
 142 }
 143
 144 static inline struct neighbour *__ipv6_neigh_lookup(struct neigh_table *tbl, struct net_device *dev, const void *pkey)
 145 {
 146         struct neigh_hash_table *nht;
 147         const u32 *p32 = pkey;
 148         struct neighbour *n;
 149         u32 hash_val;
 150
 151         rcu_read_lock_bh();
 152         nht = rcu_dereference_bh(tbl->nht);
 153         hash_val = ndisc_hashfn(pkey, dev, nht->hash_rnd) >> (32 - nht->hash_shift);
 154         for (n = rcu_dereference_bh(nht->hash_buckets[hash_val]);
 155              n != NULL;
 156              n = rcu_dereference_bh(n->next)) {
 157                 u32 *n32 = (u32 *) n->primary_key;
 158                 if (n->dev == dev &&
 159                     ((n32[0] ^ p32[0]) | (n32[1] ^ p32[1]) |
 160                      (n32[2] ^ p32[2]) | (n32[3] ^ p32[3])) == 0) {
 161                         if (!atomic_inc_not_zero(&n->refcnt))
 162                                 n = NULL;
 163                         break;
 164                 }
 165         }
 166         rcu_read_unlock_bh();
 167
 168         return n;
 169 }
 170
 171 extern int                      ndisc_init(void);
 172
 173 extern void                     ndisc_cleanup(void);
 174
 175 extern int                      ndisc_rcv(struct sk_buff *skb);
 176
 177 extern void                     ndisc_send_ns(struct net_device *dev,
 178                                               struct neighbour *neigh,
 179                                               const struct in6_addr *solicit,
 180                                               const struct in6_addr *daddr,
 181                                               const struct in6_addr *saddr);
 182
 183 extern void                     ndisc_send_rs(struct net_device *dev,
 184                                               const struct in6_addr *saddr,
 185                                               const struct in6_addr *daddr);
 186
 187 extern void                     ndisc_send_redirect(struct sk_buff *skb,
 188                                                     const struct in6_addr *target);
 189
 190 extern int                      ndisc_mc_map(const struct in6_addr *addr, char *buf,
 191                                              struct net_device *dev, int dir);
 192
 193 extern struct sk_buff           *ndisc_build_skb(struct net_device *dev,
 194                                                  const struct in6_addr *daddr,
 195                                                  const struct in6_addr *saddr,
 196                                                  struct icmp6hdr *icmp6h,
 197                                                  const struct in6_addr *target,
 198                                                  int llinfo);
 199
 200 extern void                     ndisc_send_skb(struct sk_buff *skb,
 201                                                struct net_device *dev,
 202                                                struct neighbour *neigh,
 203                                                const struct in6_addr *daddr,
 204                                                const struct in6_addr *saddr,
 205                                                struct icmp6hdr *icmp6h);
 206
 207
 208
 209 /*
 210  *      IGMP
 211  */
 212 extern int                      igmp6_init(void);
 213
 214 extern void                     igmp6_cleanup(void);
 215
 216 extern int                      igmp6_event_query(struct sk_buff *skb);
 217
 218 extern int                      igmp6_event_report(struct sk_buff *skb);
 219
 220
 221 #ifdef CONFIG_SYSCTL
 222 extern int                      ndisc_ifinfo_sysctl_change(struct ctl_table *ctl,
 223                                                            int write,
 224                                                            void __user *buffer,
 225                                                            size_t *lenp,
 226                                                            loff_t *ppos);
 227 int ndisc_ifinfo_sysctl_strategy(ctl_table *ctl,
 228                                  void __user *oldval, size_t __user *oldlenp,
 229                                  void __user *newval, size_t newlen);
 230 #endif
 231
 232 extern void                     inet6_ifinfo_notify(int event,
 233                                                     struct inet6_dev *idev);
 234
 235 #endif