ndisc.h 15 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338339340341342343344345346347348349350351352353354355356357358359360361362363364365366367368369370371372373374375376377378379380381382383384385386387388389390391392393394395396397398399400401402403404405406407408409410411412413414415416417418419420421422423424425426427428429430431432433434435436437438439440441442443444445446447448449450451452453454455456457458459460461462463464465466467468469470471472473474475476477478479480481482483484485486487488489490491492493494495496497498
  1. /* SPDX-License-Identifier: GPL-2.0 */
  2. #ifndef _NDISC_H
  3. #define _NDISC_H
  4. #include <net/ipv6_stubs.h>
  5. /*
  6. * ICMP codes for neighbour discovery messages
  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. * Router type: cross-layer information from link-layer to
  15. * IPv6 layer reported by certain link types (e.g., RFC4214).
  16. */
  17. #define NDISC_NODETYPE_UNSPEC 0 /* unspecified (default) */
  18. #define NDISC_NODETYPE_HOST 1 /* host or unauthorized router */
  19. #define NDISC_NODETYPE_NODEFAULT 2 /* non-default router */
  20. #define NDISC_NODETYPE_DEFAULT 3 /* default router */
  21. /*
  22. * ndisc options
  23. */
  24. enum {
  25. __ND_OPT_PREFIX_INFO_END = 0,
  26. ND_OPT_SOURCE_LL_ADDR = 1, /* RFC2461 */
  27. ND_OPT_TARGET_LL_ADDR = 2, /* RFC2461 */
  28. ND_OPT_PREFIX_INFO = 3, /* RFC2461 */
  29. ND_OPT_REDIRECT_HDR = 4, /* RFC2461 */
  30. ND_OPT_MTU = 5, /* RFC2461 */
  31. ND_OPT_NONCE = 14, /* RFC7527 */
  32. __ND_OPT_ARRAY_MAX,
  33. ND_OPT_ROUTE_INFO = 24, /* RFC4191 */
  34. ND_OPT_RDNSS = 25, /* RFC5006 */
  35. ND_OPT_DNSSL = 31, /* RFC6106 */
  36. ND_OPT_6CO = 34, /* RFC6775 */
  37. ND_OPT_CAPTIVE_PORTAL = 37, /* RFC7710 */
  38. ND_OPT_PREF64 = 38, /* RFC8781 */
  39. __ND_OPT_MAX
  40. };
  41. #define MAX_RTR_SOLICITATION_DELAY HZ
  42. #define ND_REACHABLE_TIME (30*HZ)
  43. #define ND_RETRANS_TIMER HZ
  44. #include <linux/compiler.h>
  45. #include <linux/icmpv6.h>
  46. #include <linux/in6.h>
  47. #include <linux/types.h>
  48. #include <linux/if_arp.h>
  49. #include <linux/netdevice.h>
  50. #include <linux/hash.h>
  51. #include <net/neighbour.h>
  52. /* Set to 3 to get tracing... */
  53. #define ND_DEBUG 1
  54. #define ND_PRINTK(val, level, fmt, ...) \
  55. do { \
  56. if (val <= ND_DEBUG) \
  57. net_##level##_ratelimited(fmt, ##__VA_ARGS__); \
  58. } while (0)
  59. struct ctl_table;
  60. struct inet6_dev;
  61. struct net_device;
  62. struct net_proto_family;
  63. struct sk_buff;
  64. struct prefix_info;
  65. extern struct neigh_table nd_tbl;
  66. struct nd_msg {
  67. struct icmp6hdr icmph;
  68. struct in6_addr target;
  69. __u8 opt[];
  70. };
  71. struct rs_msg {
  72. struct icmp6hdr icmph;
  73. __u8 opt[];
  74. };
  75. struct ra_msg {
  76. struct icmp6hdr icmph;
  77. __be32 reachable_time;
  78. __be32 retrans_timer;
  79. };
  80. struct rd_msg {
  81. struct icmp6hdr icmph;
  82. struct in6_addr target;
  83. struct in6_addr dest;
  84. __u8 opt[];
  85. };
  86. struct nd_opt_hdr {
  87. __u8 nd_opt_type;
  88. __u8 nd_opt_len;
  89. } __packed;
  90. /* ND options */
  91. struct ndisc_options {
  92. struct nd_opt_hdr *nd_opt_array[__ND_OPT_ARRAY_MAX];
  93. #ifdef CONFIG_IPV6_ROUTE_INFO
  94. struct nd_opt_hdr *nd_opts_ri;
  95. struct nd_opt_hdr *nd_opts_ri_end;
  96. #endif
  97. struct nd_opt_hdr *nd_useropts;
  98. struct nd_opt_hdr *nd_useropts_end;
  99. #if IS_ENABLED(CONFIG_IEEE802154_6LOWPAN)
  100. struct nd_opt_hdr *nd_802154_opt_array[ND_OPT_TARGET_LL_ADDR + 1];
  101. #endif
  102. };
  103. #define nd_opts_src_lladdr nd_opt_array[ND_OPT_SOURCE_LL_ADDR]
  104. #define nd_opts_tgt_lladdr nd_opt_array[ND_OPT_TARGET_LL_ADDR]
  105. #define nd_opts_pi nd_opt_array[ND_OPT_PREFIX_INFO]
  106. #define nd_opts_pi_end nd_opt_array[__ND_OPT_PREFIX_INFO_END]
  107. #define nd_opts_rh nd_opt_array[ND_OPT_REDIRECT_HDR]
  108. #define nd_opts_mtu nd_opt_array[ND_OPT_MTU]
  109. #define nd_opts_nonce nd_opt_array[ND_OPT_NONCE]
  110. #define nd_802154_opts_src_lladdr nd_802154_opt_array[ND_OPT_SOURCE_LL_ADDR]
  111. #define nd_802154_opts_tgt_lladdr nd_802154_opt_array[ND_OPT_TARGET_LL_ADDR]
  112. #define NDISC_OPT_SPACE(len) (((len)+2+7)&~7)
  113. struct ndisc_options *ndisc_parse_options(const struct net_device *dev,
  114. u8 *opt, int opt_len,
  115. struct ndisc_options *ndopts);
  116. void __ndisc_fill_addr_option(struct sk_buff *skb, int type, const void *data,
  117. int data_len, int pad);
  118. #define NDISC_OPS_REDIRECT_DATA_SPACE 2
  119. /*
  120. * This structure defines the hooks for IPv6 neighbour discovery.
  121. * The following hooks can be defined; unless noted otherwise, they are
  122. * optional and can be filled with a null pointer.
  123. *
  124. * int (*is_useropt)(u8 nd_opt_type):
  125. * This function is called when IPv6 decide RA userspace options. if
  126. * this function returns 1 then the option given by nd_opt_type will
  127. * be handled as userspace option additional to the IPv6 options.
  128. *
  129. * int (*parse_options)(const struct net_device *dev,
  130. * struct nd_opt_hdr *nd_opt,
  131. * struct ndisc_options *ndopts):
  132. * This function is called while parsing ndisc ops and put each position
  133. * as pointer into ndopts. If this function return unequal 0, then this
  134. * function took care about the ndisc option, if 0 then the IPv6 ndisc
  135. * option parser will take care about that option.
  136. *
  137. * void (*update)(const struct net_device *dev, struct neighbour *n,
  138. * u32 flags, u8 icmp6_type,
  139. * const struct ndisc_options *ndopts):
  140. * This function is called when IPv6 ndisc updates the neighbour cache
  141. * entry. Additional options which can be updated may be previously
  142. * parsed by parse_opts callback and accessible over ndopts parameter.
  143. *
  144. * int (*opt_addr_space)(const struct net_device *dev, u8 icmp6_type,
  145. * struct neighbour *neigh, u8 *ha_buf,
  146. * u8 **ha):
  147. * This function is called when the necessary option space will be
  148. * calculated before allocating a skb. The parameters neigh, ha_buf
  149. * abd ha are available on NDISC_REDIRECT messages only.
  150. *
  151. * void (*fill_addr_option)(const struct net_device *dev,
  152. * struct sk_buff *skb, u8 icmp6_type,
  153. * const u8 *ha):
  154. * This function is called when the skb will finally fill the option
  155. * fields inside skb. NOTE: this callback should fill the option
  156. * fields to the skb which are previously indicated by opt_space
  157. * parameter. That means the decision to add such option should
  158. * not lost between these two callbacks, e.g. protected by interface
  159. * up state.
  160. *
  161. * void (*prefix_rcv_add_addr)(struct net *net, struct net_device *dev,
  162. * const struct prefix_info *pinfo,
  163. * struct inet6_dev *in6_dev,
  164. * struct in6_addr *addr,
  165. * int addr_type, u32 addr_flags,
  166. * bool sllao, bool tokenized,
  167. * __u32 valid_lft, u32 prefered_lft,
  168. * bool dev_addr_generated):
  169. * This function is called when a RA messages is received with valid
  170. * PIO option fields and an IPv6 address will be added to the interface
  171. * for autoconfiguration. The parameter dev_addr_generated reports about
  172. * if the address was based on dev->dev_addr or not. This can be used
  173. * to add a second address if link-layer operates with two link layer
  174. * addresses. E.g. 802.15.4 6LoWPAN.
  175. */
  176. struct ndisc_ops {
  177. int (*is_useropt)(u8 nd_opt_type);
  178. int (*parse_options)(const struct net_device *dev,
  179. struct nd_opt_hdr *nd_opt,
  180. struct ndisc_options *ndopts);
  181. void (*update)(const struct net_device *dev, struct neighbour *n,
  182. u32 flags, u8 icmp6_type,
  183. const struct ndisc_options *ndopts);
  184. int (*opt_addr_space)(const struct net_device *dev, u8 icmp6_type,
  185. struct neighbour *neigh, u8 *ha_buf,
  186. u8 **ha);
  187. void (*fill_addr_option)(const struct net_device *dev,
  188. struct sk_buff *skb, u8 icmp6_type,
  189. const u8 *ha);
  190. void (*prefix_rcv_add_addr)(struct net *net, struct net_device *dev,
  191. const struct prefix_info *pinfo,
  192. struct inet6_dev *in6_dev,
  193. struct in6_addr *addr,
  194. int addr_type, u32 addr_flags,
  195. bool sllao, bool tokenized,
  196. __u32 valid_lft, u32 prefered_lft,
  197. bool dev_addr_generated);
  198. };
  199. #if IS_ENABLED(CONFIG_IPV6)
  200. static inline int ndisc_ops_is_useropt(const struct net_device *dev,
  201. u8 nd_opt_type)
  202. {
  203. if (dev->ndisc_ops && dev->ndisc_ops->is_useropt)
  204. return dev->ndisc_ops->is_useropt(nd_opt_type);
  205. else
  206. return 0;
  207. }
  208. static inline int ndisc_ops_parse_options(const struct net_device *dev,
  209. struct nd_opt_hdr *nd_opt,
  210. struct ndisc_options *ndopts)
  211. {
  212. if (dev->ndisc_ops && dev->ndisc_ops->parse_options)
  213. return dev->ndisc_ops->parse_options(dev, nd_opt, ndopts);
  214. else
  215. return 0;
  216. }
  217. static inline void ndisc_ops_update(const struct net_device *dev,
  218. struct neighbour *n, u32 flags,
  219. u8 icmp6_type,
  220. const struct ndisc_options *ndopts)
  221. {
  222. if (dev->ndisc_ops && dev->ndisc_ops->update)
  223. dev->ndisc_ops->update(dev, n, flags, icmp6_type, ndopts);
  224. }
  225. static inline int ndisc_ops_opt_addr_space(const struct net_device *dev,
  226. u8 icmp6_type)
  227. {
  228. if (dev->ndisc_ops && dev->ndisc_ops->opt_addr_space &&
  229. icmp6_type != NDISC_REDIRECT)
  230. return dev->ndisc_ops->opt_addr_space(dev, icmp6_type, NULL,
  231. NULL, NULL);
  232. else
  233. return 0;
  234. }
  235. static inline int ndisc_ops_redirect_opt_addr_space(const struct net_device *dev,
  236. struct neighbour *neigh,
  237. u8 *ha_buf, u8 **ha)
  238. {
  239. if (dev->ndisc_ops && dev->ndisc_ops->opt_addr_space)
  240. return dev->ndisc_ops->opt_addr_space(dev, NDISC_REDIRECT,
  241. neigh, ha_buf, ha);
  242. else
  243. return 0;
  244. }
  245. static inline void ndisc_ops_fill_addr_option(const struct net_device *dev,
  246. struct sk_buff *skb,
  247. u8 icmp6_type)
  248. {
  249. if (dev->ndisc_ops && dev->ndisc_ops->fill_addr_option &&
  250. icmp6_type != NDISC_REDIRECT)
  251. dev->ndisc_ops->fill_addr_option(dev, skb, icmp6_type, NULL);
  252. }
  253. static inline void ndisc_ops_fill_redirect_addr_option(const struct net_device *dev,
  254. struct sk_buff *skb,
  255. const u8 *ha)
  256. {
  257. if (dev->ndisc_ops && dev->ndisc_ops->fill_addr_option)
  258. dev->ndisc_ops->fill_addr_option(dev, skb, NDISC_REDIRECT, ha);
  259. }
  260. static inline void ndisc_ops_prefix_rcv_add_addr(struct net *net,
  261. struct net_device *dev,
  262. const struct prefix_info *pinfo,
  263. struct inet6_dev *in6_dev,
  264. struct in6_addr *addr,
  265. int addr_type, u32 addr_flags,
  266. bool sllao, bool tokenized,
  267. __u32 valid_lft,
  268. u32 prefered_lft,
  269. bool dev_addr_generated)
  270. {
  271. if (dev->ndisc_ops && dev->ndisc_ops->prefix_rcv_add_addr)
  272. dev->ndisc_ops->prefix_rcv_add_addr(net, dev, pinfo, in6_dev,
  273. addr, addr_type,
  274. addr_flags, sllao,
  275. tokenized, valid_lft,
  276. prefered_lft,
  277. dev_addr_generated);
  278. }
  279. #endif
  280. /*
  281. * Return the padding between the option length and the start of the
  282. * link addr. Currently only IP-over-InfiniBand needs this, although
  283. * if RFC 3831 IPv6-over-Fibre Channel is ever implemented it may
  284. * also need a pad of 2.
  285. */
  286. static inline int ndisc_addr_option_pad(unsigned short type)
  287. {
  288. switch (type) {
  289. case ARPHRD_INFINIBAND: return 2;
  290. default: return 0;
  291. }
  292. }
  293. static inline int __ndisc_opt_addr_space(unsigned char addr_len, int pad)
  294. {
  295. return NDISC_OPT_SPACE(addr_len + pad);
  296. }
  297. #if IS_ENABLED(CONFIG_IPV6)
  298. static inline int ndisc_opt_addr_space(struct net_device *dev, u8 icmp6_type)
  299. {
  300. return __ndisc_opt_addr_space(dev->addr_len,
  301. ndisc_addr_option_pad(dev->type)) +
  302. ndisc_ops_opt_addr_space(dev, icmp6_type);
  303. }
  304. static inline int ndisc_redirect_opt_addr_space(struct net_device *dev,
  305. struct neighbour *neigh,
  306. u8 *ops_data_buf,
  307. u8 **ops_data)
  308. {
  309. return __ndisc_opt_addr_space(dev->addr_len,
  310. ndisc_addr_option_pad(dev->type)) +
  311. ndisc_ops_redirect_opt_addr_space(dev, neigh, ops_data_buf,
  312. ops_data);
  313. }
  314. #endif
  315. static inline u8 *__ndisc_opt_addr_data(struct nd_opt_hdr *p,
  316. unsigned char addr_len, int prepad)
  317. {
  318. u8 *lladdr = (u8 *)(p + 1);
  319. int lladdrlen = p->nd_opt_len << 3;
  320. if (lladdrlen != __ndisc_opt_addr_space(addr_len, prepad))
  321. return NULL;
  322. return lladdr + prepad;
  323. }
  324. static inline u8 *ndisc_opt_addr_data(struct nd_opt_hdr *p,
  325. struct net_device *dev)
  326. {
  327. return __ndisc_opt_addr_data(p, dev->addr_len,
  328. ndisc_addr_option_pad(dev->type));
  329. }
  330. static inline u32 ndisc_hashfn(const void *pkey, const struct net_device *dev, __u32 *hash_rnd)
  331. {
  332. const u32 *p32 = pkey;
  333. return (((p32[0] ^ hash32_ptr(dev)) * hash_rnd[0]) +
  334. (p32[1] * hash_rnd[1]) +
  335. (p32[2] * hash_rnd[2]) +
  336. (p32[3] * hash_rnd[3]));
  337. }
  338. static inline struct neighbour *__ipv6_neigh_lookup_noref(struct net_device *dev, const void *pkey)
  339. {
  340. return ___neigh_lookup_noref(&nd_tbl, neigh_key_eq128, ndisc_hashfn, pkey, dev);
  341. }
  342. static inline
  343. struct neighbour *__ipv6_neigh_lookup_noref_stub(struct net_device *dev,
  344. const void *pkey)
  345. {
  346. return ___neigh_lookup_noref(ipv6_stub->nd_tbl, neigh_key_eq128,
  347. ndisc_hashfn, pkey, dev);
  348. }
  349. static inline struct neighbour *__ipv6_neigh_lookup(struct net_device *dev, const void *pkey)
  350. {
  351. struct neighbour *n;
  352. rcu_read_lock();
  353. n = __ipv6_neigh_lookup_noref(dev, pkey);
  354. if (n && !refcount_inc_not_zero(&n->refcnt))
  355. n = NULL;
  356. rcu_read_unlock();
  357. return n;
  358. }
  359. static inline void __ipv6_confirm_neigh(struct net_device *dev,
  360. const void *pkey)
  361. {
  362. struct neighbour *n;
  363. rcu_read_lock();
  364. n = __ipv6_neigh_lookup_noref(dev, pkey);
  365. neigh_confirm(n);
  366. rcu_read_unlock();
  367. }
  368. static inline void __ipv6_confirm_neigh_stub(struct net_device *dev,
  369. const void *pkey)
  370. {
  371. struct neighbour *n;
  372. rcu_read_lock();
  373. n = __ipv6_neigh_lookup_noref_stub(dev, pkey);
  374. neigh_confirm(n);
  375. rcu_read_unlock();
  376. }
  377. /* uses ipv6_stub and is meant for use outside of IPv6 core */
  378. static inline struct neighbour *ip_neigh_gw6(struct net_device *dev,
  379. const void *addr)
  380. {
  381. struct neighbour *neigh;
  382. neigh = __ipv6_neigh_lookup_noref_stub(dev, addr);
  383. if (unlikely(!neigh))
  384. neigh = __neigh_create(ipv6_stub->nd_tbl, addr, dev, false);
  385. return neigh;
  386. }
  387. int ndisc_init(void);
  388. int ndisc_late_init(void);
  389. void ndisc_late_cleanup(void);
  390. void ndisc_cleanup(void);
  391. int ndisc_rcv(struct sk_buff *skb);
  392. struct sk_buff *ndisc_ns_create(struct net_device *dev, const struct in6_addr *solicit,
  393. const struct in6_addr *saddr, u64 nonce);
  394. void ndisc_send_ns(struct net_device *dev, const struct in6_addr *solicit,
  395. const struct in6_addr *daddr, const struct in6_addr *saddr,
  396. u64 nonce);
  397. void ndisc_send_skb(struct sk_buff *skb, const struct in6_addr *daddr,
  398. const struct in6_addr *saddr);
  399. void ndisc_send_rs(struct net_device *dev,
  400. const struct in6_addr *saddr, const struct in6_addr *daddr);
  401. void ndisc_send_na(struct net_device *dev, const struct in6_addr *daddr,
  402. const struct in6_addr *solicited_addr,
  403. bool router, bool solicited, bool override, bool inc_opt);
  404. void ndisc_send_redirect(struct sk_buff *skb, const struct in6_addr *target);
  405. int ndisc_mc_map(const struct in6_addr *addr, char *buf, struct net_device *dev,
  406. int dir);
  407. void ndisc_update(const struct net_device *dev, struct neighbour *neigh,
  408. const u8 *lladdr, u8 new, u32 flags, u8 icmp6_type,
  409. struct ndisc_options *ndopts);
  410. /*
  411. * IGMP
  412. */
  413. int igmp6_init(void);
  414. int igmp6_late_init(void);
  415. void igmp6_cleanup(void);
  416. void igmp6_late_cleanup(void);
  417. void igmp6_event_query(struct sk_buff *skb);
  418. void igmp6_event_report(struct sk_buff *skb);
  419. #ifdef CONFIG_SYSCTL
  420. int ndisc_ifinfo_sysctl_change(struct ctl_table *ctl, int write,
  421. void *buffer, size_t *lenp, loff_t *ppos);
  422. int ndisc_ifinfo_sysctl_strategy(struct ctl_table *ctl,
  423. void __user *oldval, size_t __user *oldlenp,
  424. void __user *newval, size_t newlen);
  425. #endif
  426. void inet6_ifinfo_notify(int event, struct inet6_dev *idev);
  427. #endif