summaryrefslogtreecommitdiff
path: root/include/net/ndisc.h
blob: 31b1bb11ba3ff29f51d5023a271ee470564ebc3e (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
#ifndef _NDISC_H
#define _NDISC_H

/*
 *	ICMP codes for neighbour discovery messages
 */

#define NDISC_ROUTER_SOLICITATION	133
#define NDISC_ROUTER_ADVERTISEMENT	134
#define NDISC_NEIGHBOUR_SOLICITATION	135
#define NDISC_NEIGHBOUR_ADVERTISEMENT	136
#define NDISC_REDIRECT			137

/*
 * Router type: cross-layer information from link-layer to
 * IPv6 layer reported by certain link types (e.g., RFC4214).
 */
#define NDISC_NODETYPE_UNSPEC		0	/* unspecified (default) */
#define NDISC_NODETYPE_HOST		1	/* host or unauthorized router */
#define NDISC_NODETYPE_NODEFAULT	2	/* non-default router */
#define NDISC_NODETYPE_DEFAULT		3	/* default router */

/*
 *	ndisc options
 */

enum {
	__ND_OPT_PREFIX_INFO_END = 0,
	ND_OPT_SOURCE_LL_ADDR = 1,	/* RFC2461 */
	ND_OPT_TARGET_LL_ADDR = 2,	/* RFC2461 */
	ND_OPT_PREFIX_INFO = 3,		/* RFC2461 */
	ND_OPT_REDIRECT_HDR = 4,	/* RFC2461 */
	ND_OPT_MTU = 5,			/* RFC2461 */
	ND_OPT_NONCE = 14,              /* RFC7527 */
	__ND_OPT_ARRAY_MAX,
	ND_OPT_ROUTE_INFO = 24,		/* RFC4191 */
	ND_OPT_RDNSS = 25,		/* RFC5006 */
	ND_OPT_DNSSL = 31,		/* RFC6106 */
	ND_OPT_6CO = 34,		/* RFC6775 */
	__ND_OPT_MAX
};

#define MAX_RTR_SOLICITATION_DELAY	HZ

#define ND_REACHABLE_TIME		(30*HZ)
#define ND_RETRANS_TIMER		HZ

#include <linux/compiler.h>
#include <linux/icmpv6.h>
#include <linux/in6.h>
#include <linux/types.h>
#include <linux/if_arp.h>
#include <linux/netdevice.h>
#include <linux/hash.h>

#include <net/neighbour.h>

/* Set to 3 to get tracing... */
#define ND_DEBUG 1

#define ND_PRINTK(val, level, fmt, ...)				\
do {								\
	if (val <= ND_DEBUG)					\
		net_##level##_ratelimited(fmt, ##__VA_ARGS__);	\
} while (0)

struct ctl_table;
struct inet6_dev;
struct net_device;
struct net_proto_family;
struct sk_buff;
struct prefix_info;

extern struct neigh_table nd_tbl;

struct nd_msg {
        struct icmp6hdr	icmph;
        struct in6_addr	target;
	__u8		opt[0];
};

struct rs_msg {
	struct icmp6hdr	icmph;
	__u8		opt[0];
};

struct ra_msg {
        struct icmp6hdr		icmph;
	__be32			reachable_time;
	__be32			retrans_timer;
};

struct rd_msg {
	struct icmp6hdr icmph;
	struct in6_addr	target;
	struct in6_addr	dest;
	__u8		opt[0];
};

struct nd_opt_hdr {
	__u8		nd_opt_type;
	__u8		nd_opt_len;
} __packed;

/* ND options */
struct ndisc_options {
	struct nd_opt_hdr *nd_opt_array[__ND_OPT_ARRAY_MAX];
#ifdef CONFIG_IPV6_ROUTE_INFO
	struct nd_opt_hdr *nd_opts_ri;
	struct nd_opt_hdr *nd_opts_ri_end;
#endif
	struct nd_opt_hdr *nd_useropts;
	struct nd_opt_hdr *nd_useropts_end;
#if IS_ENABLED(CONFIG_IEEE802154_6LOWPAN)
	struct nd_opt_hdr *nd_802154_opt_array[ND_OPT_TARGET_LL_ADDR + 1];
#endif
};

#define nd_opts_src_lladdr		nd_opt_array[ND_OPT_SOURCE_LL_ADDR]
#define nd_opts_tgt_lladdr		nd_opt_array[ND_OPT_TARGET_LL_ADDR]
#define nd_opts_pi			nd_opt_array[ND_OPT_PREFIX_INFO]
#define nd_opts_pi_end			nd_opt_array[__ND_OPT_PREFIX_INFO_END]
#define nd_opts_rh			nd_opt_array[ND_OPT_REDIRECT_HDR]
#define nd_opts_mtu			nd_opt_array[ND_OPT_MTU]
#define nd_opts_nonce			nd_opt_array[ND_OPT_NONCE]
#define nd_802154_opts_src_lladdr	nd_802154_opt_array[ND_OPT_SOURCE_LL_ADDR]
#define nd_802154_opts_tgt_lladdr	nd_802154_opt_array[ND_OPT_TARGET_LL_ADDR]

#define NDISC_OPT_SPACE(len) (((len)+2+7)&~7)

struct ndisc_options *ndisc_parse_options(const struct net_device *dev,
					  u8 *opt, int opt_len,
					  struct ndisc_options *ndopts);

void __ndisc_fill_addr_option(struct sk_buff *skb, int type, void *data,
			      int data_len, int pad);

#define NDISC_OPS_REDIRECT_DATA_SPACE	2

/*
 * This structure defines the hooks for IPv6 neighbour discovery.
 * The following hooks can be defined; unless noted otherwise, they are
 * optional and can be filled with a null pointer.
 *
 * int (*is_useropt)(u8 nd_opt_type):
 *     This function is called when IPv6 decide RA userspace options. if
 *     this function returns 1 then the option given by nd_opt_type will
 *     be handled as userspace option additional to the IPv6 options.
 *
 * int (*parse_options)(const struct net_device *dev,
 *			struct nd_opt_hdr *nd_opt,
 *			struct ndisc_options *ndopts):
 *     This function is called while parsing ndisc ops and put each position
 *     as pointer into ndopts. If this function return unequal 0, then this
 *     function took care about the ndisc option, if 0 then the IPv6 ndisc
 *     option parser will take care about that option.
 *
 * void (*update)(const struct net_device *dev, struct neighbour *n,
 *		  u32 flags, u8 icmp6_type,
 *		  const struct ndisc_options *ndopts):
 *     This function is called when IPv6 ndisc updates the neighbour cache
 *     entry. Additional options which can be updated may be previously
 *     parsed by parse_opts callback and accessible over ndopts parameter.
 *
 * int (*opt_addr_space)(const struct net_device *dev, u8 icmp6_type,
 *			 struct neighbour *neigh, u8 *ha_buf,
 *			 u8 **ha):
 *     This function is called when the necessary option space will be
 *     calculated before allocating a skb. The parameters neigh, ha_buf
 *     abd ha are available on NDISC_REDIRECT messages only.
 *
 * void (*fill_addr_option)(const struct net_device *dev,
 *			    struct sk_buff *skb, u8 icmp6_type,
 *			    const u8 *ha):
 *     This function is called when the skb will finally fill the option
 *     fields inside skb. NOTE: this callback should fill the option
 *     fields to the skb which are previously indicated by opt_space
 *     parameter. That means the decision to add such option should
 *     not lost between these two callbacks, e.g. protected by interface
 *     up state.
 *
 * void (*prefix_rcv_add_addr)(struct net *net, struct net_device *dev,
 *			       const struct prefix_info *pinfo,
 *			       struct inet6_dev *in6_dev,
 *			       struct in6_addr *addr,
 *			       int addr_type, u32 addr_flags,
 *			       bool sllao, bool tokenized,
 *			       __u32 valid_lft, u32 prefered_lft,
 *			       bool dev_addr_generated):
 *     This function is called when a RA messages is received with valid
 *     PIO option fields and an IPv6 address will be added to the interface
 *     for autoconfiguration. The parameter dev_addr_generated reports about
 *     if the address was based on dev->dev_addr or not. This can be used
 *     to add a second address if link-layer operates with two link layer
 *     addresses. E.g. 802.15.4 6LoWPAN.
 */
struct ndisc_ops {
	int	(*is_useropt)(u8 nd_opt_type);
	int	(*parse_options)(const struct net_device *dev,
				 struct nd_opt_hdr *nd_opt,
				 struct ndisc_options *ndopts);
	void	(*update)(const struct net_device *dev, struct neighbour *n,
			  u32 flags, u8 icmp6_type,
			  const struct ndisc_options *ndopts);
	int	(*opt_addr_space)(const struct net_device *dev, u8 icmp6_type,
				  struct neighbour *neigh, u8 *ha_buf,
				  u8 **ha);
	void	(*fill_addr_option)(const struct net_device *dev,
				    struct sk_buff *skb, u8 icmp6_type,
				    const u8 *ha);
	void	(*prefix_rcv_add_addr)(struct net *net, struct net_device *dev,
				       const struct prefix_info *pinfo,
				       struct inet6_dev *in6_dev,
				       struct in6_addr *addr,
				       int addr_type, u32 addr_flags,
				       bool sllao, bool tokenized,
				       __u32 valid_lft, u32 prefered_lft,
				       bool dev_addr_generated);
};

#if IS_ENABLED(CONFIG_IPV6)
static inline int ndisc_ops_is_useropt(const struct net_device *dev,
				       u8 nd_opt_type)
{
	if (dev->ndisc_ops && dev->ndisc_ops->is_useropt)
		return dev->ndisc_ops->is_useropt(nd_opt_type);
	else
		return 0;
}

static inline int ndisc_ops_parse_options(const struct net_device *dev,
					  struct nd_opt_hdr *nd_opt,
					  struct ndisc_options *ndopts)
{
	if (dev->ndisc_ops && dev->ndisc_ops->parse_options)
		return dev->ndisc_ops->parse_options(dev, nd_opt, ndopts);
	else
		return 0;
}

static inline void ndisc_ops_update(const struct net_device *dev,
					  struct neighbour *n, u32 flags,
					  u8 icmp6_type,
					  const struct ndisc_options *ndopts)
{
	if (dev->ndisc_ops && dev->ndisc_ops->update)
		dev->ndisc_ops->update(dev, n, flags, icmp6_type, ndopts);
}

static inline int ndisc_ops_opt_addr_space(const struct net_device *dev,
					   u8 icmp6_type)
{
	if (dev->ndisc_ops && dev->ndisc_ops->opt_addr_space &&
	    icmp6_type != NDISC_REDIRECT)
		return dev->ndisc_ops->opt_addr_space(dev, icmp6_type, NULL,
						      NULL, NULL);
	else
		return 0;
}

static inline int ndisc_ops_redirect_opt_addr_space(const struct net_device *dev,
						    struct neighbour *neigh,
						    u8 *ha_buf, u8 **ha)
{
	if (dev->ndisc_ops && dev->ndisc_ops->opt_addr_space)
		return dev->ndisc_ops->opt_addr_space(dev, NDISC_REDIRECT,
						      neigh, ha_buf, ha);
	else
		return 0;
}

static inline void ndisc_ops_fill_addr_option(const struct net_device *dev,
					      struct sk_buff *skb,
					      u8 icmp6_type)
{
	if (dev->ndisc_ops && dev->ndisc_ops->fill_addr_option &&
	    icmp6_type != NDISC_REDIRECT)
		dev->ndisc_ops->fill_addr_option(dev, skb, icmp6_type, NULL);
}

static inline void ndisc_ops_fill_redirect_addr_option(const struct net_device *dev,
						       struct sk_buff *skb,
						       const u8 *ha)
{
	if (dev->ndisc_ops && dev->ndisc_ops->fill_addr_option)
		dev->ndisc_ops->fill_addr_option(dev, skb, NDISC_REDIRECT, ha);
}

static inline void ndisc_ops_prefix_rcv_add_addr(struct net *net,
						 struct net_device *dev,
						 const struct prefix_info *pinfo,
						 struct inet6_dev *in6_dev,
						 struct in6_addr *addr,
						 int addr_type, u32 addr_flags,
						 bool sllao, bool tokenized,
						 __u32 valid_lft,
						 u32 prefered_lft,
						 bool dev_addr_generated)
{
	if (dev->ndisc_ops && dev->ndisc_ops->prefix_rcv_add_addr)
		dev->ndisc_ops->prefix_rcv_add_addr(net, dev, pinfo, in6_dev,
						    addr, addr_type,
						    addr_flags, sllao,
						    tokenized, valid_lft,
						    prefered_lft,
						    dev_addr_generated);
}
#endif

/*
 * Return the padding between the option length and the start of the
 * link addr.  Currently only IP-over-InfiniBand needs this, although
 * if RFC 3831 IPv6-over-Fibre Channel is ever implemented it may
 * also need a pad of 2.
 */
static inline int ndisc_addr_option_pad(unsigned short type)
{
	switch (type) {
	case ARPHRD_INFINIBAND: return 2;
	default:                return 0;
	}
}

static inline int __ndisc_opt_addr_space(unsigned char addr_len, int pad)
{
	return NDISC_OPT_SPACE(addr_len + pad);
}

#if IS_ENABLED(CONFIG_IPV6)
static inline int ndisc_opt_addr_space(struct net_device *dev, u8 icmp6_type)
{
	return __ndisc_opt_addr_space(dev->addr_len,
				      ndisc_addr_option_pad(dev->type)) +
		ndisc_ops_opt_addr_space(dev, icmp6_type);
}

static inline int ndisc_redirect_opt_addr_space(struct net_device *dev,
						struct neighbour *neigh,
						u8 *ops_data_buf,
						u8 **ops_data)
{
	return __ndisc_opt_addr_space(dev->addr_len,
				      ndisc_addr_option_pad(dev->type)) +
		ndisc_ops_redirect_opt_addr_space(dev, neigh, ops_data_buf,
						  ops_data);
}
#endif

static inline u8 *__ndisc_opt_addr_data(struct nd_opt_hdr *p,
					unsigned char addr_len, int prepad)
{
	u8 *lladdr = (u8 *)(p + 1);
	int lladdrlen = p->nd_opt_len << 3;
	if (lladdrlen != __ndisc_opt_addr_space(addr_len, prepad))
		return NULL;
	return lladdr + prepad;
}

static inline u8 *ndisc_opt_addr_data(struct nd_opt_hdr *p,
				      struct net_device *dev)
{
	return __ndisc_opt_addr_data(p, dev->addr_len,
				     ndisc_addr_option_pad(dev->type));
}

static inline u32 ndisc_hashfn(const void *pkey, const struct net_device *dev, __u32 *hash_rnd)
{
	const u32 *p32 = pkey;

	return (((p32[0] ^ hash32_ptr(dev)) * hash_rnd[0]) +
		(p32[1] * hash_rnd[1]) +
		(p32[2] * hash_rnd[2]) +
		(p32[3] * hash_rnd[3]));
}

static inline struct neighbour *__ipv6_neigh_lookup_noref(struct net_device *dev, const void *pkey)
{
	return ___neigh_lookup_noref(&nd_tbl, neigh_key_eq128, ndisc_hashfn, pkey, dev);
}

static inline struct neighbour *__ipv6_neigh_lookup(struct net_device *dev, const void *pkey)
{
	struct neighbour *n;

	rcu_read_lock_bh();
	n = __ipv6_neigh_lookup_noref(dev, pkey);
	if (n && !refcount_inc_not_zero(&n->refcnt))
		n = NULL;
	rcu_read_unlock_bh();

	return n;
}

static inline void __ipv6_confirm_neigh(struct net_device *dev,
					const void *pkey)
{
	struct neighbour *n;

	rcu_read_lock_bh();
	n = __ipv6_neigh_lookup_noref(dev, pkey);
	if (n) {
		unsigned long now = jiffies;

		/* avoid dirtying neighbour */
		if (n->confirmed != now)
			n->confirmed = now;
	}
	rcu_read_unlock_bh();
}

int ndisc_init(void);
int ndisc_late_init(void);

void ndisc_late_cleanup(void);
void ndisc_cleanup(void);

int ndisc_rcv(struct sk_buff *skb);

void ndisc_send_ns(struct net_device *dev, const struct in6_addr *solicit,
		   const struct in6_addr *daddr, const struct in6_addr *saddr,
		   u64 nonce);

void ndisc_send_rs(struct net_device *dev,
		   const struct in6_addr *saddr, const struct in6_addr *daddr);
void ndisc_send_na(struct net_device *dev, const struct in6_addr *daddr,
		   const struct in6_addr *solicited_addr,
		   bool router, bool solicited, bool override, bool inc_opt);

void ndisc_send_redirect(struct sk_buff *skb, const struct in6_addr *target);

int ndisc_mc_map(const struct in6_addr *addr, char *buf, struct net_device *dev,
		 int dir);

void ndisc_update(const struct net_device *dev, struct neighbour *neigh,
		  const u8 *lladdr, u8 new, u32 flags, u8 icmp6_type,
		  struct ndisc_options *ndopts);

/*
 *	IGMP
 */
int igmp6_init(void);
int igmp6_late_init(void);

void igmp6_cleanup(void);
void igmp6_late_cleanup(void);

int igmp6_event_query(struct sk_buff *skb);

int igmp6_event_report(struct sk_buff *skb);


#ifdef CONFIG_SYSCTL
int ndisc_ifinfo_sysctl_change(struct ctl_table *ctl, int write,
			       void __user *buffer, size_t *lenp, loff_t *ppos);
int ndisc_ifinfo_sysctl_strategy(struct ctl_table *ctl,
				 void __user *oldval, size_t __user *oldlenp,
				 void __user *newval, size_t newlen);
#endif

void inet6_ifinfo_notify(int event, struct inet6_dev *idev);

#endif