LXR linux/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
  27enum {
  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_6CO = 34,                /* RFC6775 */
  39        __ND_OPT_MAX
  40};
  41
  42#define MAX_RTR_SOLICITATION_DELAY      HZ
  43
  44#define ND_REACHABLE_TIME               (30*HZ)
  45#define ND_RETRANS_TIMER                HZ
  46
  47#include <linux/compiler.h>
  48#include <linux/icmpv6.h>
  49#include <linux/in6.h>
  50#include <linux/types.h>
  51#include <linux/if_arp.h>
  52#include <linux/netdevice.h>
  53#include <linux/hash.h>
  54
  55#include <net/neighbour.h>
  56
  57/* Set to 3 to get tracing... */
  58#define ND_DEBUG 1
  59
  60#define ND_PRINTK(val, level, fmt, ...)                         \
  61do {                                                            \
  62        if (val <= ND_DEBUG)                                    \
  63                net_##level##_ratelimited(fmt, ##__VA_ARGS__);  \
  64} while (0)
  65
  66struct ctl_table;
  67struct inet6_dev;
  68struct net_device;
  69struct net_proto_family;
  70struct sk_buff;
  71struct prefix_info;
  72
  73extern struct neigh_table nd_tbl;
  74
  75struct nd_msg {
  76        struct icmp6hdr icmph;
  77        struct in6_addr target;
  78        __u8            opt[0];
  79};
  80
  81struct rs_msg {
  82        struct icmp6hdr icmph;
  83        __u8            opt[0];
  84};
  85
  86struct ra_msg {
  87        struct icmp6hdr         icmph;
  88        __be32                  reachable_time;
  89        __be32                  retrans_timer;
  90};
  91
  92struct rd_msg {
  93        struct icmp6hdr icmph;
  94        struct in6_addr target;
  95        struct in6_addr dest;
  96        __u8            opt[0];
  97};
  98
  99struct nd_opt_hdr {
 100        __u8            nd_opt_type;
 101        __u8            nd_opt_len;
 102} __packed;
 103
 104/* ND options */
 105struct ndisc_options {
 106        struct nd_opt_hdr *nd_opt_array[__ND_OPT_ARRAY_MAX];
 107#ifdef CONFIG_IPV6_ROUTE_INFO
 108        struct nd_opt_hdr *nd_opts_ri;
 109        struct nd_opt_hdr *nd_opts_ri_end;
 110#endif
 111        struct nd_opt_hdr *nd_useropts;
 112        struct nd_opt_hdr *nd_useropts_end;
 113#if IS_ENABLED(CONFIG_IEEE802154_6LOWPAN)
 114        struct nd_opt_hdr *nd_802154_opt_array[ND_OPT_TARGET_LL_ADDR + 1];
 115#endif
 116};
 117
 118#define nd_opts_src_lladdr              nd_opt_array[ND_OPT_SOURCE_LL_ADDR]
 119#define nd_opts_tgt_lladdr              nd_opt_array[ND_OPT_TARGET_LL_ADDR]
 120#define nd_opts_pi                      nd_opt_array[ND_OPT_PREFIX_INFO]
 121#define nd_opts_pi_end                  nd_opt_array[__ND_OPT_PREFIX_INFO_END]
 122#define nd_opts_rh                      nd_opt_array[ND_OPT_REDIRECT_HDR]
 123#define nd_opts_mtu                     nd_opt_array[ND_OPT_MTU]
 124#define nd_802154_opts_src_lladdr       nd_802154_opt_array[ND_OPT_SOURCE_LL_ADDR]
 125#define nd_802154_opts_tgt_lladdr       nd_802154_opt_array[ND_OPT_TARGET_LL_ADDR]
 126
 127#define NDISC_OPT_SPACE(len) (((len)+2+7)&~7)
 128
 129struct ndisc_options *ndisc_parse_options(const struct net_device *dev,
 130                                          u8 *opt, int opt_len,
 131                                          struct ndisc_options *ndopts);
 132
 133void __ndisc_fill_addr_option(struct sk_buff *skb, int type, void *data,
 134                              int data_len, int pad);
 135
 136#define NDISC_OPS_REDIRECT_DATA_SPACE   2
 137
 138/*
 139 * This structure defines the hooks for IPv6 neighbour discovery.
 140 * The following hooks can be defined; unless noted otherwise, they are
 141 * optional and can be filled with a null pointer.
 142 *
 143 * int (*is_useropt)(u8 nd_opt_type):
 144 *     This function is called when IPv6 decide RA userspace options. if
 145 *     this function returns 1 then the option given by nd_opt_type will
 146 *     be handled as userspace option additional to the IPv6 options.
 147 *
 148 * int (*parse_options)(const struct net_device *dev,
 149 *                      struct nd_opt_hdr *nd_opt,
 150 *                      struct ndisc_options *ndopts):
 151 *     This function is called while parsing ndisc ops and put each position
 152 *     as pointer into ndopts. If this function return unequal 0, then this
 153 *     function took care about the ndisc option, if 0 then the IPv6 ndisc
 154 *     option parser will take care about that option.
 155 *
 156 * void (*update)(const struct net_device *dev, struct neighbour *n,
 157 *                u32 flags, u8 icmp6_type,
 158 *                const struct ndisc_options *ndopts):
 159 *     This function is called when IPv6 ndisc updates the neighbour cache
 160 *     entry. Additional options which can be updated may be previously
 161 *     parsed by parse_opts callback and accessible over ndopts parameter.
 162 *
 163 * int (*opt_addr_space)(const struct net_device *dev, u8 icmp6_type,
 164 *                       struct neighbour *neigh, u8 *ha_buf,
 165 *                       u8 **ha):
 166 *     This function is called when the necessary option space will be
 167 *     calculated before allocating a skb. The parameters neigh, ha_buf
 168 *     abd ha are available on NDISC_REDIRECT messages only.
 169 *
 170 * void (*fill_addr_option)(const struct net_device *dev,
 171 *                          struct sk_buff *skb, u8 icmp6_type,
 172 *                          const u8 *ha):
 173 *     This function is called when the skb will finally fill the option
 174 *     fields inside skb. NOTE: this callback should fill the option
 175 *     fields to the skb which are previously indicated by opt_space
 176 *     parameter. That means the decision to add such option should
 177 *     not lost between these two callbacks, e.g. protected by interface
 178 *     up state.
 179 *
 180 * void (*prefix_rcv_add_addr)(struct net *net, struct net_device *dev,
 181 *                             const struct prefix_info *pinfo,
 182 *                             struct inet6_dev *in6_dev,
 183 *                             struct in6_addr *addr,
 184 *                             int addr_type, u32 addr_flags,
 185 *                             bool sllao, bool tokenized,
 186 *                             __u32 valid_lft, u32 prefered_lft,
 187 *                             bool dev_addr_generated):
 188 *     This function is called when a RA messages is received with valid
 189 *     PIO option fields and an IPv6 address will be added to the interface
 190 *     for autoconfiguration. The parameter dev_addr_generated reports about
 191 *     if the address was based on dev->dev_addr or not. This can be used
 192 *     to add a second address if link-layer operates with two link layer
 193 *     addresses. E.g. 802.15.4 6LoWPAN.
 194 */
 195struct ndisc_ops {
 196        int     (*is_useropt)(u8 nd_opt_type);
 197        int     (*parse_options)(const struct net_device *dev,
 198                                 struct nd_opt_hdr *nd_opt,
 199                                 struct ndisc_options *ndopts);
 200        void    (*update)(const struct net_device *dev, struct neighbour *n,
 201                          u32 flags, u8 icmp6_type,
 202                          const struct ndisc_options *ndopts);
 203        int     (*opt_addr_space)(const struct net_device *dev, u8 icmp6_type,
 204                                  struct neighbour *neigh, u8 *ha_buf,
 205                                  u8 **ha);
 206        void    (*fill_addr_option)(const struct net_device *dev,
 207                                    struct sk_buff *skb, u8 icmp6_type,
 208                                    const u8 *ha);
 209        void    (*prefix_rcv_add_addr)(struct net *net, struct net_device *dev,
 210                                       const struct prefix_info *pinfo,
 211                                       struct inet6_dev *in6_dev,
 212                                       struct in6_addr *addr,
 213                                       int addr_type, u32 addr_flags,
 214                                       bool sllao, bool tokenized,
 215                                       __u32 valid_lft, u32 prefered_lft,
 216                                       bool dev_addr_generated);
 217};
 218
 219#if IS_ENABLED(CONFIG_IPV6)
 220static inline int ndisc_ops_is_useropt(const struct net_device *dev,
 221                                       u8 nd_opt_type)
 222{
 223        if (dev->ndisc_ops && dev->ndisc_ops->is_useropt)
 224                return dev->ndisc_ops->is_useropt(nd_opt_type);
 225        else
 226                return 0;
 227}
 228
 229static inline int ndisc_ops_parse_options(const struct net_device *dev,
 230                                          struct nd_opt_hdr *nd_opt,
 231                                          struct ndisc_options *ndopts)
 232{
 233        if (dev->ndisc_ops && dev->ndisc_ops->parse_options)
 234                return dev->ndisc_ops->parse_options(dev, nd_opt, ndopts);
 235        else
 236                return 0;
 237}
 238
 239static inline void ndisc_ops_update(const struct net_device *dev,
 240                                          struct neighbour *n, u32 flags,
 241                                          u8 icmp6_type,
 242                                          const struct ndisc_options *ndopts)
 243{
 244        if (dev->ndisc_ops && dev->ndisc_ops->update)
 245                dev->ndisc_ops->update(dev, n, flags, icmp6_type, ndopts);
 246}
 247
 248static inline int ndisc_ops_opt_addr_space(const struct net_device *dev,
 249                                           u8 icmp6_type)
 250{
 251        if (dev->ndisc_ops && dev->ndisc_ops->opt_addr_space &&
 252            icmp6_type != NDISC_REDIRECT)
 253                return dev->ndisc_ops->opt_addr_space(dev, icmp6_type, NULL,
 254                                                      NULL, NULL);
 255        else
 256                return 0;
 257}
 258
 259static inline int ndisc_ops_redirect_opt_addr_space(const struct net_device *dev,
 260                                                    struct neighbour *neigh,
 261                                                    u8 *ha_buf, u8 **ha)
 262{
 263        if (dev->ndisc_ops && dev->ndisc_ops->opt_addr_space)
 264                return dev->ndisc_ops->opt_addr_space(dev, NDISC_REDIRECT,
 265                                                      neigh, ha_buf, ha);
 266        else
 267                return 0;
 268}
 269
 270static inline void ndisc_ops_fill_addr_option(const struct net_device *dev,
 271                                              struct sk_buff *skb,
 272                                              u8 icmp6_type)
 273{
 274        if (dev->ndisc_ops && dev->ndisc_ops->fill_addr_option &&
 275            icmp6_type != NDISC_REDIRECT)
 276                dev->ndisc_ops->fill_addr_option(dev, skb, icmp6_type, NULL);
 277}
 278
 279static inline void ndisc_ops_fill_redirect_addr_option(const struct net_device *dev,
 280                                                       struct sk_buff *skb,
 281                                                       const u8 *ha)
 282{
 283        if (dev->ndisc_ops && dev->ndisc_ops->fill_addr_option)
 284                dev->ndisc_ops->fill_addr_option(dev, skb, NDISC_REDIRECT, ha);
 285}
 286
 287static inline void ndisc_ops_prefix_rcv_add_addr(struct net *net,
 288                                                 struct net_device *dev,
 289                                                 const struct prefix_info *pinfo,
 290                                                 struct inet6_dev *in6_dev,
 291                                                 struct in6_addr *addr,
 292                                                 int addr_type, u32 addr_flags,
 293                                                 bool sllao, bool tokenized,
 294                                                 __u32 valid_lft,
 295                                                 u32 prefered_lft,
 296                                                 bool dev_addr_generated)
 297{
 298        if (dev->ndisc_ops && dev->ndisc_ops->prefix_rcv_add_addr)
 299                dev->ndisc_ops->prefix_rcv_add_addr(net, dev, pinfo, in6_dev,
 300                                                    addr, addr_type,
 301                                                    addr_flags, sllao,
 302                                                    tokenized, valid_lft,
 303                                                    prefered_lft,
 304                                                    dev_addr_generated);
 305}
 306#endif
 307
 308/*
 309 * Return the padding between the option length and the start of the
 310 * link addr.  Currently only IP-over-InfiniBand needs this, although
 311 * if RFC 3831 IPv6-over-Fibre Channel is ever implemented it may
 312 * also need a pad of 2.
 313 */
 314static inline int ndisc_addr_option_pad(unsigned short type)
 315{
 316        switch (type) {
 317        case ARPHRD_INFINIBAND: return 2;
 318        default:                return 0;
 319        }
 320}
 321
 322static inline int __ndisc_opt_addr_space(unsigned char addr_len, int pad)
 323{
 324        return NDISC_OPT_SPACE(addr_len + pad);
 325}
 326
 327#if IS_ENABLED(CONFIG_IPV6)
 328static inline int ndisc_opt_addr_space(struct net_device *dev, u8 icmp6_type)
 329{
 330        return __ndisc_opt_addr_space(dev->addr_len,
 331                                      ndisc_addr_option_pad(dev->type)) +
 332                ndisc_ops_opt_addr_space(dev, icmp6_type);
 333}
 334
 335static inline int ndisc_redirect_opt_addr_space(struct net_device *dev,
 336                                                struct neighbour *neigh,
 337                                                u8 *ops_data_buf,
 338                                                u8 **ops_data)
 339{
 340        return __ndisc_opt_addr_space(dev->addr_len,
 341                                      ndisc_addr_option_pad(dev->type)) +
 342                ndisc_ops_redirect_opt_addr_space(dev, neigh, ops_data_buf,
 343                                                  ops_data);
 344}
 345#endif
 346
 347static inline u8 *__ndisc_opt_addr_data(struct nd_opt_hdr *p,
 348                                        unsigned char addr_len, int prepad)
 349{
 350        u8 *lladdr = (u8 *)(p + 1);
 351        int lladdrlen = p->nd_opt_len << 3;
 352        if (lladdrlen != __ndisc_opt_addr_space(addr_len, prepad))
 353                return NULL;
 354        return lladdr + prepad;
 355}
 356
 357static inline u8 *ndisc_opt_addr_data(struct nd_opt_hdr *p,
 358                                      struct net_device *dev)
 359{
 360        return __ndisc_opt_addr_data(p, dev->addr_len,
 361                                     ndisc_addr_option_pad(dev->type));
 362}
 363
 364static inline u32 ndisc_hashfn(const void *pkey, const struct net_device *dev, __u32 *hash_rnd)
 365{
 366        const u32 *p32 = pkey;
 367
 368        return (((p32[0] ^ hash32_ptr(dev)) * hash_rnd[0]) +
 369                (p32[1] * hash_rnd[1]) +
 370                (p32[2] * hash_rnd[2]) +
 371                (p32[3] * hash_rnd[3]));
 372}
 373
 374static inline struct neighbour *__ipv6_neigh_lookup_noref(struct net_device *dev, const void *pkey)
 375{
 376        return ___neigh_lookup_noref(&nd_tbl, neigh_key_eq128, ndisc_hashfn, pkey, dev);
 377}
 378
 379static inline struct neighbour *__ipv6_neigh_lookup(struct net_device *dev, const void *pkey)
 380{
 381        struct neighbour *n;
 382
 383        rcu_read_lock_bh();
 384        n = __ipv6_neigh_lookup_noref(dev, pkey);
 385        if (n && !atomic_inc_not_zero(&n->refcnt))
 386                n = NULL;
 387        rcu_read_unlock_bh();
 388
 389        return n;
 390}
 391
 392int ndisc_init(void);
 393int ndisc_late_init(void);
 394
 395void ndisc_late_cleanup(void);
 396void ndisc_cleanup(void);
 397
 398int ndisc_rcv(struct sk_buff *skb);
 399
 400void ndisc_send_ns(struct net_device *dev, const struct in6_addr *solicit,
 401                   const struct in6_addr *daddr, const struct in6_addr *saddr);
 402
 403void ndisc_send_rs(struct net_device *dev,
 404                   const struct in6_addr *saddr, const struct in6_addr *daddr);
 405void ndisc_send_na(struct net_device *dev, const struct in6_addr *daddr,
 406                   const struct in6_addr *solicited_addr,
 407                   bool router, bool solicited, bool override, bool inc_opt);
 408
 409void ndisc_send_redirect(struct sk_buff *skb, const struct in6_addr *target);
 410
 411int ndisc_mc_map(const struct in6_addr *addr, char *buf, struct net_device *dev,
 412                 int dir);
 413
 414void ndisc_update(const struct net_device *dev, struct neighbour *neigh,
 415                  const u8 *lladdr, u8 new, u32 flags, u8 icmp6_type,
 416                  struct ndisc_options *ndopts);
 417
 418/*
 419 *      IGMP
 420 */
 421int igmp6_init(void);
 422
 423void igmp6_cleanup(void);
 424
 425int igmp6_event_query(struct sk_buff *skb);
 426
 427int igmp6_event_report(struct sk_buff *skb);
 428
 429
 430#ifdef CONFIG_SYSCTL
 431int ndisc_ifinfo_sysctl_change(struct ctl_table *ctl, int write,
 432                               void __user *buffer, size_t *lenp, loff_t *ppos);
 433int ndisc_ifinfo_sysctl_strategy(struct ctl_table *ctl,
 434                                 void __user *oldval, size_t __user *oldlenp,
 435                                 void __user *newval, size_t newlen);
 436#endif
 437
 438void inet6_ifinfo_notify(int event, struct inet6_dev *idev);
 439
 440#endif
 441