1 | /* SPDX-License-Identifier: GPL-2.0 */ |
2 | #ifndef _NDISC_H |
3 | #define _NDISC_H |
4 | |
5 | #include <net/ipv6_stubs.h> |
6 | |
7 | /* |
8 | * ICMP codes for neighbour discovery messages |
9 | */ |
10 | |
11 | #define NDISC_ROUTER_SOLICITATION 133 |
12 | #define NDISC_ROUTER_ADVERTISEMENT 134 |
13 | #define NDISC_NEIGHBOUR_SOLICITATION 135 |
14 | #define NDISC_NEIGHBOUR_ADVERTISEMENT 136 |
15 | #define NDISC_REDIRECT 137 |
16 | |
17 | /* |
18 | * Router type: cross-layer information from link-layer to |
19 | * IPv6 layer reported by certain link types (e.g., RFC4214). |
20 | */ |
21 | #define NDISC_NODETYPE_UNSPEC 0 /* unspecified (default) */ |
22 | #define NDISC_NODETYPE_HOST 1 /* host or unauthorized router */ |
23 | #define NDISC_NODETYPE_NODEFAULT 2 /* non-default router */ |
24 | #define NDISC_NODETYPE_DEFAULT 3 /* default router */ |
25 | |
26 | /* |
27 | * ndisc options |
28 | */ |
29 | |
30 | enum { |
31 | __ND_OPT_PREFIX_INFO_END = 0, |
32 | ND_OPT_SOURCE_LL_ADDR = 1, /* RFC2461 */ |
33 | ND_OPT_TARGET_LL_ADDR = 2, /* RFC2461 */ |
34 | ND_OPT_PREFIX_INFO = 3, /* RFC2461 */ |
35 | ND_OPT_REDIRECT_HDR = 4, /* RFC2461 */ |
36 | ND_OPT_MTU = 5, /* RFC2461 */ |
37 | ND_OPT_NONCE = 14, /* RFC7527 */ |
38 | __ND_OPT_ARRAY_MAX, |
39 | ND_OPT_ROUTE_INFO = 24, /* RFC4191 */ |
40 | ND_OPT_RDNSS = 25, /* RFC5006 */ |
41 | ND_OPT_DNSSL = 31, /* RFC6106 */ |
42 | ND_OPT_6CO = 34, /* RFC6775 */ |
43 | ND_OPT_CAPTIVE_PORTAL = 37, /* RFC7710 */ |
44 | ND_OPT_PREF64 = 38, /* RFC8781 */ |
45 | __ND_OPT_MAX |
46 | }; |
47 | |
48 | #define MAX_RTR_SOLICITATION_DELAY HZ |
49 | |
50 | #define ND_REACHABLE_TIME (30*HZ) |
51 | #define ND_RETRANS_TIMER HZ |
52 | |
53 | #include <linux/compiler.h> |
54 | #include <linux/icmpv6.h> |
55 | #include <linux/in6.h> |
56 | #include <linux/types.h> |
57 | #include <linux/if_arp.h> |
58 | #include <linux/netdevice.h> |
59 | #include <linux/hash.h> |
60 | |
61 | #include <net/neighbour.h> |
62 | |
63 | /* Set to 3 to get tracing... */ |
64 | #define ND_DEBUG 1 |
65 | |
66 | #define ND_PRINTK(val, level, fmt, ...) \ |
67 | do { \ |
68 | if (val <= ND_DEBUG) \ |
69 | net_##level##_ratelimited(fmt, ##__VA_ARGS__); \ |
70 | } while (0) |
71 | |
72 | struct ctl_table; |
73 | struct inet6_dev; |
74 | struct net_device; |
75 | struct net_proto_family; |
76 | struct sk_buff; |
77 | struct prefix_info; |
78 | |
79 | extern struct neigh_table nd_tbl; |
80 | |
81 | struct nd_msg { |
82 | struct icmp6hdr icmph; |
83 | struct in6_addr target; |
84 | __u8 opt[]; |
85 | }; |
86 | |
87 | struct rs_msg { |
88 | struct icmp6hdr icmph; |
89 | __u8 opt[]; |
90 | }; |
91 | |
92 | struct ra_msg { |
93 | struct icmp6hdr icmph; |
94 | __be32 reachable_time; |
95 | __be32 retrans_timer; |
96 | }; |
97 | |
98 | struct rd_msg { |
99 | struct icmp6hdr icmph; |
100 | struct in6_addr target; |
101 | struct in6_addr dest; |
102 | __u8 opt[]; |
103 | }; |
104 | |
105 | struct nd_opt_hdr { |
106 | __u8 nd_opt_type; |
107 | __u8 nd_opt_len; |
108 | } __packed; |
109 | |
110 | /* ND options */ |
111 | struct ndisc_options { |
112 | struct nd_opt_hdr *nd_opt_array[__ND_OPT_ARRAY_MAX]; |
113 | #ifdef CONFIG_IPV6_ROUTE_INFO |
114 | struct nd_opt_hdr *nd_opts_ri; |
115 | struct nd_opt_hdr *nd_opts_ri_end; |
116 | #endif |
117 | struct nd_opt_hdr *nd_useropts; |
118 | struct nd_opt_hdr *nd_useropts_end; |
119 | #if IS_ENABLED(CONFIG_IEEE802154_6LOWPAN) |
120 | struct nd_opt_hdr *nd_802154_opt_array[ND_OPT_TARGET_LL_ADDR + 1]; |
121 | #endif |
122 | }; |
123 | |
124 | #define nd_opts_src_lladdr nd_opt_array[ND_OPT_SOURCE_LL_ADDR] |
125 | #define nd_opts_tgt_lladdr nd_opt_array[ND_OPT_TARGET_LL_ADDR] |
126 | #define nd_opts_pi nd_opt_array[ND_OPT_PREFIX_INFO] |
127 | #define nd_opts_pi_end nd_opt_array[__ND_OPT_PREFIX_INFO_END] |
128 | #define nd_opts_rh nd_opt_array[ND_OPT_REDIRECT_HDR] |
129 | #define nd_opts_mtu nd_opt_array[ND_OPT_MTU] |
130 | #define nd_opts_nonce nd_opt_array[ND_OPT_NONCE] |
131 | #define nd_802154_opts_src_lladdr nd_802154_opt_array[ND_OPT_SOURCE_LL_ADDR] |
132 | #define nd_802154_opts_tgt_lladdr nd_802154_opt_array[ND_OPT_TARGET_LL_ADDR] |
133 | |
134 | #define NDISC_OPT_SPACE(len) (((len)+2+7)&~7) |
135 | |
136 | struct ndisc_options *ndisc_parse_options(const struct net_device *dev, |
137 | u8 *opt, int opt_len, |
138 | struct ndisc_options *ndopts); |
139 | |
140 | void __ndisc_fill_addr_option(struct sk_buff *skb, int type, const void *data, |
141 | int data_len, int pad); |
142 | |
143 | #define NDISC_OPS_REDIRECT_DATA_SPACE 2 |
144 | |
145 | /* |
146 | * This structure defines the hooks for IPv6 neighbour discovery. |
147 | * The following hooks can be defined; unless noted otherwise, they are |
148 | * optional and can be filled with a null pointer. |
149 | * |
150 | * int (*is_useropt)(u8 nd_opt_type): |
151 | * This function is called when IPv6 decide RA userspace options. if |
152 | * this function returns 1 then the option given by nd_opt_type will |
153 | * be handled as userspace option additional to the IPv6 options. |
154 | * |
155 | * int (*parse_options)(const struct net_device *dev, |
156 | * struct nd_opt_hdr *nd_opt, |
157 | * struct ndisc_options *ndopts): |
158 | * This function is called while parsing ndisc ops and put each position |
159 | * as pointer into ndopts. If this function return unequal 0, then this |
160 | * function took care about the ndisc option, if 0 then the IPv6 ndisc |
161 | * option parser will take care about that option. |
162 | * |
163 | * void (*update)(const struct net_device *dev, struct neighbour *n, |
164 | * u32 flags, u8 icmp6_type, |
165 | * const struct ndisc_options *ndopts): |
166 | * This function is called when IPv6 ndisc updates the neighbour cache |
167 | * entry. Additional options which can be updated may be previously |
168 | * parsed by parse_opts callback and accessible over ndopts parameter. |
169 | * |
170 | * int (*opt_addr_space)(const struct net_device *dev, u8 icmp6_type, |
171 | * struct neighbour *neigh, u8 *ha_buf, |
172 | * u8 **ha): |
173 | * This function is called when the necessary option space will be |
174 | * calculated before allocating a skb. The parameters neigh, ha_buf |
175 | * abd ha are available on NDISC_REDIRECT messages only. |
176 | * |
177 | * void (*fill_addr_option)(const struct net_device *dev, |
178 | * struct sk_buff *skb, u8 icmp6_type, |
179 | * const u8 *ha): |
180 | * This function is called when the skb will finally fill the option |
181 | * fields inside skb. NOTE: this callback should fill the option |
182 | * fields to the skb which are previously indicated by opt_space |
183 | * parameter. That means the decision to add such option should |
184 | * not lost between these two callbacks, e.g. protected by interface |
185 | * up state. |
186 | * |
187 | * void (*prefix_rcv_add_addr)(struct net *net, struct net_device *dev, |
188 | * const struct prefix_info *pinfo, |
189 | * struct inet6_dev *in6_dev, |
190 | * struct in6_addr *addr, |
191 | * int addr_type, u32 addr_flags, |
192 | * bool sllao, bool tokenized, |
193 | * __u32 valid_lft, u32 prefered_lft, |
194 | * bool dev_addr_generated): |
195 | * This function is called when a RA messages is received with valid |
196 | * PIO option fields and an IPv6 address will be added to the interface |
197 | * for autoconfiguration. The parameter dev_addr_generated reports about |
198 | * if the address was based on dev->dev_addr or not. This can be used |
199 | * to add a second address if link-layer operates with two link layer |
200 | * addresses. E.g. 802.15.4 6LoWPAN. |
201 | */ |
202 | struct ndisc_ops { |
203 | int (*is_useropt)(u8 nd_opt_type); |
204 | int (*parse_options)(const struct net_device *dev, |
205 | struct nd_opt_hdr *nd_opt, |
206 | struct ndisc_options *ndopts); |
207 | void (*update)(const struct net_device *dev, struct neighbour *n, |
208 | u32 flags, u8 icmp6_type, |
209 | const struct ndisc_options *ndopts); |
210 | int (*opt_addr_space)(const struct net_device *dev, u8 icmp6_type, |
211 | struct neighbour *neigh, u8 *ha_buf, |
212 | u8 **ha); |
213 | void (*fill_addr_option)(const struct net_device *dev, |
214 | struct sk_buff *skb, u8 icmp6_type, |
215 | const u8 *ha); |
216 | void (*prefix_rcv_add_addr)(struct net *net, struct net_device *dev, |
217 | const struct prefix_info *pinfo, |
218 | struct inet6_dev *in6_dev, |
219 | struct in6_addr *addr, |
220 | int addr_type, u32 addr_flags, |
221 | bool sllao, bool tokenized, |
222 | __u32 valid_lft, u32 prefered_lft, |
223 | bool dev_addr_generated); |
224 | }; |
225 | |
226 | #if IS_ENABLED(CONFIG_IPV6) |
227 | static inline int ndisc_ops_is_useropt(const struct net_device *dev, |
228 | u8 nd_opt_type) |
229 | { |
230 | if (dev->ndisc_ops && dev->ndisc_ops->is_useropt) |
231 | return dev->ndisc_ops->is_useropt(nd_opt_type); |
232 | else |
233 | return 0; |
234 | } |
235 | |
236 | static inline int ndisc_ops_parse_options(const struct net_device *dev, |
237 | struct nd_opt_hdr *nd_opt, |
238 | struct ndisc_options *ndopts) |
239 | { |
240 | if (dev->ndisc_ops && dev->ndisc_ops->parse_options) |
241 | return dev->ndisc_ops->parse_options(dev, nd_opt, ndopts); |
242 | else |
243 | return 0; |
244 | } |
245 | |
246 | static inline void ndisc_ops_update(const struct net_device *dev, |
247 | struct neighbour *n, u32 flags, |
248 | u8 icmp6_type, |
249 | const struct ndisc_options *ndopts) |
250 | { |
251 | if (dev->ndisc_ops && dev->ndisc_ops->update) |
252 | dev->ndisc_ops->update(dev, n, flags, icmp6_type, ndopts); |
253 | } |
254 | |
255 | static inline int ndisc_ops_opt_addr_space(const struct net_device *dev, |
256 | u8 icmp6_type) |
257 | { |
258 | if (dev->ndisc_ops && dev->ndisc_ops->opt_addr_space && |
259 | icmp6_type != NDISC_REDIRECT) |
260 | return dev->ndisc_ops->opt_addr_space(dev, icmp6_type, NULL, |
261 | NULL, NULL); |
262 | else |
263 | return 0; |
264 | } |
265 | |
266 | static inline int ndisc_ops_redirect_opt_addr_space(const struct net_device *dev, |
267 | struct neighbour *neigh, |
268 | u8 *ha_buf, u8 **ha) |
269 | { |
270 | if (dev->ndisc_ops && dev->ndisc_ops->opt_addr_space) |
271 | return dev->ndisc_ops->opt_addr_space(dev, NDISC_REDIRECT, |
272 | neigh, ha_buf, ha); |
273 | else |
274 | return 0; |
275 | } |
276 | |
277 | static inline void ndisc_ops_fill_addr_option(const struct net_device *dev, |
278 | struct sk_buff *skb, |
279 | u8 icmp6_type) |
280 | { |
281 | if (dev->ndisc_ops && dev->ndisc_ops->fill_addr_option && |
282 | icmp6_type != NDISC_REDIRECT) |
283 | dev->ndisc_ops->fill_addr_option(dev, skb, icmp6_type, NULL); |
284 | } |
285 | |
286 | static inline void ndisc_ops_fill_redirect_addr_option(const struct net_device *dev, |
287 | struct sk_buff *skb, |
288 | const u8 *ha) |
289 | { |
290 | if (dev->ndisc_ops && dev->ndisc_ops->fill_addr_option) |
291 | dev->ndisc_ops->fill_addr_option(dev, skb, NDISC_REDIRECT, ha); |
292 | } |
293 | |
294 | static inline void ndisc_ops_prefix_rcv_add_addr(struct net *net, |
295 | struct net_device *dev, |
296 | const struct prefix_info *pinfo, |
297 | struct inet6_dev *in6_dev, |
298 | struct in6_addr *addr, |
299 | int addr_type, u32 addr_flags, |
300 | bool sllao, bool tokenized, |
301 | __u32 valid_lft, |
302 | u32 prefered_lft, |
303 | bool dev_addr_generated) |
304 | { |
305 | if (dev->ndisc_ops && dev->ndisc_ops->prefix_rcv_add_addr) |
306 | dev->ndisc_ops->prefix_rcv_add_addr(net, dev, pinfo, in6_dev, |
307 | addr, addr_type, |
308 | addr_flags, sllao, |
309 | tokenized, valid_lft, |
310 | prefered_lft, |
311 | dev_addr_generated); |
312 | } |
313 | #endif |
314 | |
315 | /* |
316 | * Return the padding between the option length and the start of the |
317 | * link addr. Currently only IP-over-InfiniBand needs this, although |
318 | * if RFC 3831 IPv6-over-Fibre Channel is ever implemented it may |
319 | * also need a pad of 2. |
320 | */ |
321 | static inline int ndisc_addr_option_pad(unsigned short type) |
322 | { |
323 | switch (type) { |
324 | case ARPHRD_INFINIBAND: return 2; |
325 | default: return 0; |
326 | } |
327 | } |
328 | |
329 | static inline int __ndisc_opt_addr_space(unsigned char addr_len, int pad) |
330 | { |
331 | return NDISC_OPT_SPACE(addr_len + pad); |
332 | } |
333 | |
334 | #if IS_ENABLED(CONFIG_IPV6) |
335 | static inline int ndisc_opt_addr_space(struct net_device *dev, u8 icmp6_type) |
336 | { |
337 | return __ndisc_opt_addr_space(addr_len: dev->addr_len, |
338 | pad: ndisc_addr_option_pad(type: dev->type)) + |
339 | ndisc_ops_opt_addr_space(dev, icmp6_type); |
340 | } |
341 | |
342 | static inline int ndisc_redirect_opt_addr_space(struct net_device *dev, |
343 | struct neighbour *neigh, |
344 | u8 *ops_data_buf, |
345 | u8 **ops_data) |
346 | { |
347 | return __ndisc_opt_addr_space(addr_len: dev->addr_len, |
348 | pad: ndisc_addr_option_pad(type: dev->type)) + |
349 | ndisc_ops_redirect_opt_addr_space(dev, neigh, ha_buf: ops_data_buf, |
350 | ha: ops_data); |
351 | } |
352 | #endif |
353 | |
354 | static inline u8 *__ndisc_opt_addr_data(struct nd_opt_hdr *p, |
355 | unsigned char addr_len, int prepad) |
356 | { |
357 | u8 *lladdr = (u8 *)(p + 1); |
358 | int lladdrlen = p->nd_opt_len << 3; |
359 | if (lladdrlen != __ndisc_opt_addr_space(addr_len, pad: prepad)) |
360 | return NULL; |
361 | return lladdr + prepad; |
362 | } |
363 | |
364 | static inline u8 *ndisc_opt_addr_data(struct nd_opt_hdr *p, |
365 | struct net_device *dev) |
366 | { |
367 | return __ndisc_opt_addr_data(p, addr_len: dev->addr_len, |
368 | prepad: ndisc_addr_option_pad(type: dev->type)); |
369 | } |
370 | |
371 | static inline u32 ndisc_hashfn(const void *pkey, const struct net_device *dev, __u32 *hash_rnd) |
372 | { |
373 | const u32 *p32 = pkey; |
374 | |
375 | return (((p32[0] ^ hash32_ptr(ptr: dev)) * hash_rnd[0]) + |
376 | (p32[1] * hash_rnd[1]) + |
377 | (p32[2] * hash_rnd[2]) + |
378 | (p32[3] * hash_rnd[3])); |
379 | } |
380 | |
381 | static inline struct neighbour *__ipv6_neigh_lookup_noref(struct net_device *dev, const void *pkey) |
382 | { |
383 | return ___neigh_lookup_noref(tbl: &nd_tbl, key_eq: neigh_key_eq128, hash: ndisc_hashfn, pkey, dev); |
384 | } |
385 | |
386 | static inline |
387 | struct neighbour *__ipv6_neigh_lookup_noref_stub(struct net_device *dev, |
388 | const void *pkey) |
389 | { |
390 | return ___neigh_lookup_noref(tbl: ipv6_stub->nd_tbl, key_eq: neigh_key_eq128, |
391 | hash: ndisc_hashfn, pkey, dev); |
392 | } |
393 | |
394 | static inline struct neighbour *__ipv6_neigh_lookup(struct net_device *dev, const void *pkey) |
395 | { |
396 | struct neighbour *n; |
397 | |
398 | rcu_read_lock(); |
399 | n = __ipv6_neigh_lookup_noref(dev, pkey); |
400 | if (n && !refcount_inc_not_zero(r: &n->refcnt)) |
401 | n = NULL; |
402 | rcu_read_unlock(); |
403 | |
404 | return n; |
405 | } |
406 | |
407 | static inline void __ipv6_confirm_neigh(struct net_device *dev, |
408 | const void *pkey) |
409 | { |
410 | struct neighbour *n; |
411 | |
412 | rcu_read_lock(); |
413 | n = __ipv6_neigh_lookup_noref(dev, pkey); |
414 | neigh_confirm(n); |
415 | rcu_read_unlock(); |
416 | } |
417 | |
418 | static inline void __ipv6_confirm_neigh_stub(struct net_device *dev, |
419 | const void *pkey) |
420 | { |
421 | struct neighbour *n; |
422 | |
423 | rcu_read_lock(); |
424 | n = __ipv6_neigh_lookup_noref_stub(dev, pkey); |
425 | neigh_confirm(n); |
426 | rcu_read_unlock(); |
427 | } |
428 | |
429 | /* uses ipv6_stub and is meant for use outside of IPv6 core */ |
430 | static inline struct neighbour *ip_neigh_gw6(struct net_device *dev, |
431 | const void *addr) |
432 | { |
433 | struct neighbour *neigh; |
434 | |
435 | neigh = __ipv6_neigh_lookup_noref_stub(dev, pkey: addr); |
436 | if (unlikely(!neigh)) |
437 | neigh = __neigh_create(tbl: ipv6_stub->nd_tbl, pkey: addr, dev, want_ref: false); |
438 | |
439 | return neigh; |
440 | } |
441 | |
442 | int ndisc_init(void); |
443 | int ndisc_late_init(void); |
444 | |
445 | void ndisc_late_cleanup(void); |
446 | void ndisc_cleanup(void); |
447 | |
448 | enum skb_drop_reason ndisc_rcv(struct sk_buff *skb); |
449 | |
450 | struct sk_buff *ndisc_ns_create(struct net_device *dev, const struct in6_addr *solicit, |
451 | const struct in6_addr *saddr, u64 nonce); |
452 | void ndisc_send_ns(struct net_device *dev, const struct in6_addr *solicit, |
453 | const struct in6_addr *daddr, const struct in6_addr *saddr, |
454 | u64 nonce); |
455 | |
456 | void ndisc_send_skb(struct sk_buff *skb, const struct in6_addr *daddr, |
457 | const struct in6_addr *saddr); |
458 | |
459 | void ndisc_send_rs(struct net_device *dev, |
460 | const struct in6_addr *saddr, const struct in6_addr *daddr); |
461 | void ndisc_send_na(struct net_device *dev, const struct in6_addr *daddr, |
462 | const struct in6_addr *solicited_addr, |
463 | bool router, bool solicited, bool override, bool inc_opt); |
464 | |
465 | void ndisc_send_redirect(struct sk_buff *skb, const struct in6_addr *target); |
466 | |
467 | int ndisc_mc_map(const struct in6_addr *addr, char *buf, struct net_device *dev, |
468 | int dir); |
469 | |
470 | void ndisc_update(const struct net_device *dev, struct neighbour *neigh, |
471 | const u8 *lladdr, u8 new, u32 flags, u8 icmp6_type, |
472 | struct ndisc_options *ndopts); |
473 | |
474 | /* |
475 | * IGMP |
476 | */ |
477 | int igmp6_init(void); |
478 | int igmp6_late_init(void); |
479 | |
480 | void igmp6_cleanup(void); |
481 | void igmp6_late_cleanup(void); |
482 | |
483 | void igmp6_event_query(struct sk_buff *skb); |
484 | |
485 | void igmp6_event_report(struct sk_buff *skb); |
486 | |
487 | |
488 | #ifdef CONFIG_SYSCTL |
489 | int ndisc_ifinfo_sysctl_change(struct ctl_table *ctl, int write, |
490 | void *buffer, size_t *lenp, loff_t *ppos); |
491 | #endif |
492 | |
493 | void inet6_ifinfo_notify(int event, struct inet6_dev *idev); |
494 | |
495 | #endif |
496 | |