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