ndisc.h 14 KB

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  1. #ifndef _NDISC_H
  2. #define _NDISC_H
  3. /*
  4. * ICMP codes for neighbour discovery messages
  5. */
  6. #define NDISC_ROUTER_SOLICITATION 133
  7. #define NDISC_ROUTER_ADVERTISEMENT 134
  8. #define NDISC_NEIGHBOUR_SOLICITATION 135
  9. #define NDISC_NEIGHBOUR_ADVERTISEMENT 136
  10. #define NDISC_REDIRECT 137
  11. /*
  12. * Router type: cross-layer information from link-layer to
  13. * IPv6 layer reported by certain link types (e.g., RFC4214).
  14. */
  15. #define NDISC_NODETYPE_UNSPEC 0 /* unspecified (default) */
  16. #define NDISC_NODETYPE_HOST 1 /* host or unauthorized router */
  17. #define NDISC_NODETYPE_NODEFAULT 2 /* non-default router */
  18. #define NDISC_NODETYPE_DEFAULT 3 /* default router */
  19. /*
  20. * ndisc options
  21. */
  22. enum {
  23. __ND_OPT_PREFIX_INFO_END = 0,
  24. ND_OPT_SOURCE_LL_ADDR = 1, /* RFC2461 */
  25. ND_OPT_TARGET_LL_ADDR = 2, /* RFC2461 */
  26. ND_OPT_PREFIX_INFO = 3, /* RFC2461 */
  27. ND_OPT_REDIRECT_HDR = 4, /* RFC2461 */
  28. ND_OPT_MTU = 5, /* RFC2461 */
  29. ND_OPT_NONCE = 14, /* RFC7527 */
  30. __ND_OPT_ARRAY_MAX,
  31. ND_OPT_ROUTE_INFO = 24, /* RFC4191 */
  32. ND_OPT_RDNSS = 25, /* RFC5006 */
  33. ND_OPT_DNSSL = 31, /* RFC6106 */
  34. ND_OPT_6CO = 34, /* RFC6775 */
  35. __ND_OPT_MAX
  36. };
  37. #define MAX_RTR_SOLICITATION_DELAY HZ
  38. #define ND_REACHABLE_TIME (30*HZ)
  39. #define ND_RETRANS_TIMER HZ
  40. #include <linux/compiler.h>
  41. #include <linux/icmpv6.h>
  42. #include <linux/in6.h>
  43. #include <linux/types.h>
  44. #include <linux/if_arp.h>
  45. #include <linux/netdevice.h>
  46. #include <linux/hash.h>
  47. #include <net/neighbour.h>
  48. /* Set to 3 to get tracing... */
  49. #define ND_DEBUG 1
  50. #define ND_PRINTK(val, level, fmt, ...) \
  51. do { \
  52. if (val <= ND_DEBUG) \
  53. net_##level##_ratelimited(fmt, ##__VA_ARGS__); \
  54. } while (0)
  55. struct ctl_table;
  56. struct inet6_dev;
  57. struct net_device;
  58. struct net_proto_family;
  59. struct sk_buff;
  60. struct prefix_info;
  61. extern struct neigh_table nd_tbl;
  62. struct nd_msg {
  63. struct icmp6hdr icmph;
  64. struct in6_addr target;
  65. __u8 opt[0];
  66. };
  67. struct rs_msg {
  68. struct icmp6hdr icmph;
  69. __u8 opt[0];
  70. };
  71. struct ra_msg {
  72. struct icmp6hdr icmph;
  73. __be32 reachable_time;
  74. __be32 retrans_timer;
  75. };
  76. struct rd_msg {
  77. struct icmp6hdr icmph;
  78. struct in6_addr target;
  79. struct in6_addr dest;
  80. __u8 opt[0];
  81. };
  82. struct nd_opt_hdr {
  83. __u8 nd_opt_type;
  84. __u8 nd_opt_len;
  85. } __packed;
  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. #if IS_ENABLED(CONFIG_IEEE802154_6LOWPAN)
  96. struct nd_opt_hdr *nd_802154_opt_array[ND_OPT_TARGET_LL_ADDR + 1];
  97. #endif
  98. };
  99. #define nd_opts_src_lladdr nd_opt_array[ND_OPT_SOURCE_LL_ADDR]
  100. #define nd_opts_tgt_lladdr nd_opt_array[ND_OPT_TARGET_LL_ADDR]
  101. #define nd_opts_pi nd_opt_array[ND_OPT_PREFIX_INFO]
  102. #define nd_opts_pi_end nd_opt_array[__ND_OPT_PREFIX_INFO_END]
  103. #define nd_opts_rh nd_opt_array[ND_OPT_REDIRECT_HDR]
  104. #define nd_opts_mtu nd_opt_array[ND_OPT_MTU]
  105. #define nd_opts_nonce nd_opt_array[ND_OPT_NONCE]
  106. #define nd_802154_opts_src_lladdr nd_802154_opt_array[ND_OPT_SOURCE_LL_ADDR]
  107. #define nd_802154_opts_tgt_lladdr nd_802154_opt_array[ND_OPT_TARGET_LL_ADDR]
  108. #define NDISC_OPT_SPACE(len) (((len)+2+7)&~7)
  109. struct ndisc_options *ndisc_parse_options(const struct net_device *dev,
  110. u8 *opt, int opt_len,
  111. struct ndisc_options *ndopts);
  112. void __ndisc_fill_addr_option(struct sk_buff *skb, int type, void *data,
  113. int data_len, int pad);
  114. #define NDISC_OPS_REDIRECT_DATA_SPACE 2
  115. /*
  116. * This structure defines the hooks for IPv6 neighbour discovery.
  117. * The following hooks can be defined; unless noted otherwise, they are
  118. * optional and can be filled with a null pointer.
  119. *
  120. * int (*is_useropt)(u8 nd_opt_type):
  121. * This function is called when IPv6 decide RA userspace options. if
  122. * this function returns 1 then the option given by nd_opt_type will
  123. * be handled as userspace option additional to the IPv6 options.
  124. *
  125. * int (*parse_options)(const struct net_device *dev,
  126. * struct nd_opt_hdr *nd_opt,
  127. * struct ndisc_options *ndopts):
  128. * This function is called while parsing ndisc ops and put each position
  129. * as pointer into ndopts. If this function return unequal 0, then this
  130. * function took care about the ndisc option, if 0 then the IPv6 ndisc
  131. * option parser will take care about that option.
  132. *
  133. * void (*update)(const struct net_device *dev, struct neighbour *n,
  134. * u32 flags, u8 icmp6_type,
  135. * const struct ndisc_options *ndopts):
  136. * This function is called when IPv6 ndisc updates the neighbour cache
  137. * entry. Additional options which can be updated may be previously
  138. * parsed by parse_opts callback and accessible over ndopts parameter.
  139. *
  140. * int (*opt_addr_space)(const struct net_device *dev, u8 icmp6_type,
  141. * struct neighbour *neigh, u8 *ha_buf,
  142. * u8 **ha):
  143. * This function is called when the necessary option space will be
  144. * calculated before allocating a skb. The parameters neigh, ha_buf
  145. * abd ha are available on NDISC_REDIRECT messages only.
  146. *
  147. * void (*fill_addr_option)(const struct net_device *dev,
  148. * struct sk_buff *skb, u8 icmp6_type,
  149. * const u8 *ha):
  150. * This function is called when the skb will finally fill the option
  151. * fields inside skb. NOTE: this callback should fill the option
  152. * fields to the skb which are previously indicated by opt_space
  153. * parameter. That means the decision to add such option should
  154. * not lost between these two callbacks, e.g. protected by interface
  155. * up state.
  156. *
  157. * void (*prefix_rcv_add_addr)(struct net *net, struct net_device *dev,
  158. * const struct prefix_info *pinfo,
  159. * struct inet6_dev *in6_dev,
  160. * struct in6_addr *addr,
  161. * int addr_type, u32 addr_flags,
  162. * bool sllao, bool tokenized,
  163. * __u32 valid_lft, u32 prefered_lft,
  164. * bool dev_addr_generated):
  165. * This function is called when a RA messages is received with valid
  166. * PIO option fields and an IPv6 address will be added to the interface
  167. * for autoconfiguration. The parameter dev_addr_generated reports about
  168. * if the address was based on dev->dev_addr or not. This can be used
  169. * to add a second address if link-layer operates with two link layer
  170. * addresses. E.g. 802.15.4 6LoWPAN.
  171. */
  172. struct ndisc_ops {
  173. int (*is_useropt)(u8 nd_opt_type);
  174. int (*parse_options)(const struct net_device *dev,
  175. struct nd_opt_hdr *nd_opt,
  176. struct ndisc_options *ndopts);
  177. void (*update)(const struct net_device *dev, struct neighbour *n,
  178. u32 flags, u8 icmp6_type,
  179. const struct ndisc_options *ndopts);
  180. int (*opt_addr_space)(const struct net_device *dev, u8 icmp6_type,
  181. struct neighbour *neigh, u8 *ha_buf,
  182. u8 **ha);
  183. void (*fill_addr_option)(const struct net_device *dev,
  184. struct sk_buff *skb, u8 icmp6_type,
  185. const u8 *ha);
  186. void (*prefix_rcv_add_addr)(struct net *net, struct net_device *dev,
  187. const struct prefix_info *pinfo,
  188. struct inet6_dev *in6_dev,
  189. struct in6_addr *addr,
  190. int addr_type, u32 addr_flags,
  191. bool sllao, bool tokenized,
  192. __u32 valid_lft, u32 prefered_lft,
  193. bool dev_addr_generated);
  194. };
  195. #if IS_ENABLED(CONFIG_IPV6)
  196. static inline int ndisc_ops_is_useropt(const struct net_device *dev,
  197. u8 nd_opt_type)
  198. {
  199. if (dev->ndisc_ops && dev->ndisc_ops->is_useropt)
  200. return dev->ndisc_ops->is_useropt(nd_opt_type);
  201. else
  202. return 0;
  203. }
  204. static inline int ndisc_ops_parse_options(const struct net_device *dev,
  205. struct nd_opt_hdr *nd_opt,
  206. struct ndisc_options *ndopts)
  207. {
  208. if (dev->ndisc_ops && dev->ndisc_ops->parse_options)
  209. return dev->ndisc_ops->parse_options(dev, nd_opt, ndopts);
  210. else
  211. return 0;
  212. }
  213. static inline void ndisc_ops_update(const struct net_device *dev,
  214. struct neighbour *n, u32 flags,
  215. u8 icmp6_type,
  216. const struct ndisc_options *ndopts)
  217. {
  218. if (dev->ndisc_ops && dev->ndisc_ops->update)
  219. dev->ndisc_ops->update(dev, n, flags, icmp6_type, ndopts);
  220. }
  221. static inline int ndisc_ops_opt_addr_space(const struct net_device *dev,
  222. u8 icmp6_type)
  223. {
  224. if (dev->ndisc_ops && dev->ndisc_ops->opt_addr_space &&
  225. icmp6_type != NDISC_REDIRECT)
  226. return dev->ndisc_ops->opt_addr_space(dev, icmp6_type, NULL,
  227. NULL, NULL);
  228. else
  229. return 0;
  230. }
  231. static inline int ndisc_ops_redirect_opt_addr_space(const struct net_device *dev,
  232. struct neighbour *neigh,
  233. u8 *ha_buf, u8 **ha)
  234. {
  235. if (dev->ndisc_ops && dev->ndisc_ops->opt_addr_space)
  236. return dev->ndisc_ops->opt_addr_space(dev, NDISC_REDIRECT,
  237. neigh, ha_buf, ha);
  238. else
  239. return 0;
  240. }
  241. static inline void ndisc_ops_fill_addr_option(const struct net_device *dev,
  242. struct sk_buff *skb,
  243. u8 icmp6_type)
  244. {
  245. if (dev->ndisc_ops && dev->ndisc_ops->fill_addr_option &&
  246. icmp6_type != NDISC_REDIRECT)
  247. dev->ndisc_ops->fill_addr_option(dev, skb, icmp6_type, NULL);
  248. }
  249. static inline void ndisc_ops_fill_redirect_addr_option(const struct net_device *dev,
  250. struct sk_buff *skb,
  251. const u8 *ha)
  252. {
  253. if (dev->ndisc_ops && dev->ndisc_ops->fill_addr_option)
  254. dev->ndisc_ops->fill_addr_option(dev, skb, NDISC_REDIRECT, ha);
  255. }
  256. static inline void ndisc_ops_prefix_rcv_add_addr(struct net *net,
  257. struct net_device *dev,
  258. const struct prefix_info *pinfo,
  259. struct inet6_dev *in6_dev,
  260. struct in6_addr *addr,
  261. int addr_type, u32 addr_flags,
  262. bool sllao, bool tokenized,
  263. __u32 valid_lft,
  264. u32 prefered_lft,
  265. bool dev_addr_generated)
  266. {
  267. if (dev->ndisc_ops && dev->ndisc_ops->prefix_rcv_add_addr)
  268. dev->ndisc_ops->prefix_rcv_add_addr(net, dev, pinfo, in6_dev,
  269. addr, addr_type,
  270. addr_flags, sllao,
  271. tokenized, valid_lft,
  272. prefered_lft,
  273. dev_addr_generated);
  274. }
  275. #endif
  276. /*
  277. * Return the padding between the option length and the start of the
  278. * link addr. Currently only IP-over-InfiniBand needs this, although
  279. * if RFC 3831 IPv6-over-Fibre Channel is ever implemented it may
  280. * also need a pad of 2.
  281. */
  282. static inline int ndisc_addr_option_pad(unsigned short type)
  283. {
  284. switch (type) {
  285. case ARPHRD_INFINIBAND: return 2;
  286. default: return 0;
  287. }
  288. }
  289. static inline int __ndisc_opt_addr_space(unsigned char addr_len, int pad)
  290. {
  291. return NDISC_OPT_SPACE(addr_len + pad);
  292. }
  293. #if IS_ENABLED(CONFIG_IPV6)
  294. static inline int ndisc_opt_addr_space(struct net_device *dev, u8 icmp6_type)
  295. {
  296. return __ndisc_opt_addr_space(dev->addr_len,
  297. ndisc_addr_option_pad(dev->type)) +
  298. ndisc_ops_opt_addr_space(dev, icmp6_type);
  299. }
  300. static inline int ndisc_redirect_opt_addr_space(struct net_device *dev,
  301. struct neighbour *neigh,
  302. u8 *ops_data_buf,
  303. u8 **ops_data)
  304. {
  305. return __ndisc_opt_addr_space(dev->addr_len,
  306. ndisc_addr_option_pad(dev->type)) +
  307. ndisc_ops_redirect_opt_addr_space(dev, neigh, ops_data_buf,
  308. ops_data);
  309. }
  310. #endif
  311. static inline u8 *__ndisc_opt_addr_data(struct nd_opt_hdr *p,
  312. unsigned char addr_len, int prepad)
  313. {
  314. u8 *lladdr = (u8 *)(p + 1);
  315. int lladdrlen = p->nd_opt_len << 3;
  316. if (lladdrlen != __ndisc_opt_addr_space(addr_len, prepad))
  317. return NULL;
  318. return lladdr + prepad;
  319. }
  320. static inline u8 *ndisc_opt_addr_data(struct nd_opt_hdr *p,
  321. struct net_device *dev)
  322. {
  323. return __ndisc_opt_addr_data(p, dev->addr_len,
  324. ndisc_addr_option_pad(dev->type));
  325. }
  326. static inline u32 ndisc_hashfn(const void *pkey, const struct net_device *dev, __u32 *hash_rnd)
  327. {
  328. const u32 *p32 = pkey;
  329. return (((p32[0] ^ hash32_ptr(dev)) * hash_rnd[0]) +
  330. (p32[1] * hash_rnd[1]) +
  331. (p32[2] * hash_rnd[2]) +
  332. (p32[3] * hash_rnd[3]));
  333. }
  334. static inline struct neighbour *__ipv6_neigh_lookup_noref(struct net_device *dev, const void *pkey)
  335. {
  336. return ___neigh_lookup_noref(&nd_tbl, neigh_key_eq128, ndisc_hashfn, pkey, dev);
  337. }
  338. static inline struct neighbour *__ipv6_neigh_lookup(struct net_device *dev, const void *pkey)
  339. {
  340. struct neighbour *n;
  341. rcu_read_lock_bh();
  342. n = __ipv6_neigh_lookup_noref(dev, pkey);
  343. if (n && !atomic_inc_not_zero(&n->refcnt))
  344. n = NULL;
  345. rcu_read_unlock_bh();
  346. return n;
  347. }
  348. static inline void __ipv6_confirm_neigh(struct net_device *dev,
  349. const void *pkey)
  350. {
  351. struct neighbour *n;
  352. rcu_read_lock_bh();
  353. n = __ipv6_neigh_lookup_noref(dev, pkey);
  354. if (n) {
  355. unsigned long now = jiffies;
  356. /* avoid dirtying neighbour */
  357. if (n->confirmed != now)
  358. n->confirmed = now;
  359. }
  360. rcu_read_unlock_bh();
  361. }
  362. int ndisc_init(void);
  363. int ndisc_late_init(void);
  364. void ndisc_late_cleanup(void);
  365. void ndisc_cleanup(void);
  366. int ndisc_rcv(struct sk_buff *skb);
  367. void ndisc_send_ns(struct net_device *dev, const struct in6_addr *solicit,
  368. const struct in6_addr *daddr, const struct in6_addr *saddr,
  369. u64 nonce);
  370. void ndisc_send_rs(struct net_device *dev,
  371. const struct in6_addr *saddr, const struct in6_addr *daddr);
  372. void ndisc_send_na(struct net_device *dev, const struct in6_addr *daddr,
  373. const struct in6_addr *solicited_addr,
  374. bool router, bool solicited, bool override, bool inc_opt);
  375. void ndisc_send_redirect(struct sk_buff *skb, const struct in6_addr *target);
  376. int ndisc_mc_map(const struct in6_addr *addr, char *buf, struct net_device *dev,
  377. int dir);
  378. void ndisc_update(const struct net_device *dev, struct neighbour *neigh,
  379. const u8 *lladdr, u8 new, u32 flags, u8 icmp6_type,
  380. struct ndisc_options *ndopts);
  381. /*
  382. * IGMP
  383. */
  384. int igmp6_init(void);
  385. int igmp6_late_init(void);
  386. void igmp6_cleanup(void);
  387. void igmp6_late_cleanup(void);
  388. int igmp6_event_query(struct sk_buff *skb);
  389. int igmp6_event_report(struct sk_buff *skb);
  390. #ifdef CONFIG_SYSCTL
  391. int ndisc_ifinfo_sysctl_change(struct ctl_table *ctl, int write,
  392. void __user *buffer, size_t *lenp, loff_t *ppos);
  393. int ndisc_ifinfo_sysctl_strategy(struct ctl_table *ctl,
  394. void __user *oldval, size_t __user *oldlenp,
  395. void __user *newval, size_t newlen);
  396. #endif
  397. void inet6_ifinfo_notify(int event, struct inet6_dev *idev);
  398. #endif