xref: /linux/include/net/addrconf.h (revision 07214013578b156d0fda288a0311d353ea149674)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ADDRCONF_H
3 #define _ADDRCONF_H
4 
5 #define MAX_RTR_SOLICITATIONS		-1		/* unlimited */
6 #define RTR_SOLICITATION_INTERVAL	(4*HZ)
7 #define RTR_SOLICITATION_MAX_INTERVAL	(3600*HZ)	/* 1 hour */
8 
9 #define MIN_VALID_LIFETIME		(2*3600)	/* 2 hours */
10 
11 #define TEMP_VALID_LIFETIME		(7*86400)       /* 1 week */
12 #define TEMP_PREFERRED_LIFETIME		(86400)         /* 24 hours */
13 #define REGEN_MIN_ADVANCE		(2)             /* 2 seconds */
14 #define REGEN_MAX_RETRY			(3)
15 #define MAX_DESYNC_FACTOR		(600)
16 
17 #define ADDR_CHECK_FREQUENCY		(120*HZ)
18 
19 #define IPV6_MAX_ADDRESSES		16
20 
21 #define ADDRCONF_TIMER_FUZZ_MINUS	(HZ > 50 ? HZ / 50 : 1)
22 #define ADDRCONF_TIMER_FUZZ		(HZ / 4)
23 #define ADDRCONF_TIMER_FUZZ_MAX		(HZ)
24 
25 #define ADDRCONF_NOTIFY_PRIORITY	0
26 
27 #include <linux/in.h>
28 #include <linux/in6.h>
29 
30 struct prefix_info {
31 	__u8			type;
32 	__u8			length;
33 	__u8			prefix_len;
34 
35 	union __packed {
36 		__u8		flags;
37 		struct __packed {
38 #if defined(__BIG_ENDIAN_BITFIELD)
39 			__u8	onlink : 1,
40 			 	autoconf : 1,
41 				reserved : 6;
42 #elif defined(__LITTLE_ENDIAN_BITFIELD)
43 			__u8	reserved : 6,
44 				autoconf : 1,
45 				onlink : 1;
46 #else
47 #error "Please fix <asm/byteorder.h>"
48 #endif
49 		};
50 	};
51 	__be32			valid;
52 	__be32			prefered;
53 	__be32			reserved2;
54 
55 	struct in6_addr		prefix;
56 };
57 
58 /* rfc4861 4.6.2: IPv6 PIO is 32 bytes in size */
59 static_assert(sizeof(struct prefix_info) == 32);
60 
61 #include <linux/ipv6.h>
62 #include <linux/netdevice.h>
63 #include <net/if_inet6.h>
64 #include <net/ipv6.h>
65 
66 struct in6_validator_info {
67 	struct in6_addr		i6vi_addr;
68 	struct inet6_dev	*i6vi_dev;
69 	struct netlink_ext_ack	*extack;
70 };
71 
72 struct ifa6_config {
73 	const struct in6_addr	*pfx;
74 	unsigned int		plen;
75 
76 	u8			ifa_proto;
77 
78 	const struct in6_addr	*peer_pfx;
79 
80 	u32			rt_priority;
81 	u32			ifa_flags;
82 	u32			preferred_lft;
83 	u32			valid_lft;
84 	u16			scope;
85 };
86 
87 int addrconf_init(void);
88 void addrconf_cleanup(void);
89 
90 int addrconf_add_ifaddr(struct net *net, void __user *arg);
91 int addrconf_del_ifaddr(struct net *net, void __user *arg);
92 int addrconf_set_dstaddr(struct net *net, void __user *arg);
93 
94 int ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
95 		  const struct net_device *dev, int strict);
96 int ipv6_chk_addr_and_flags(struct net *net, const struct in6_addr *addr,
97 			    const struct net_device *dev, bool skip_dev_check,
98 			    int strict, u32 banned_flags);
99 
100 #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
101 int ipv6_chk_home_addr(struct net *net, const struct in6_addr *addr);
102 #endif
103 
104 int ipv6_chk_rpl_srh_loop(struct net *net, const struct in6_addr *segs,
105 			  unsigned char nsegs);
106 
107 bool ipv6_chk_custom_prefix(const struct in6_addr *addr,
108 				   const unsigned int prefix_len,
109 				   struct net_device *dev);
110 
111 int ipv6_chk_prefix(const struct in6_addr *addr, struct net_device *dev);
112 
113 struct net_device *ipv6_dev_find(struct net *net, const struct in6_addr *addr,
114 				 struct net_device *dev);
115 
116 struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net,
117 				     const struct in6_addr *addr,
118 				     struct net_device *dev, int strict);
119 
120 int ipv6_dev_get_saddr(struct net *net, const struct net_device *dev,
121 		       const struct in6_addr *daddr, unsigned int srcprefs,
122 		       struct in6_addr *saddr);
123 int ipv6_get_lladdr(struct net_device *dev, struct in6_addr *addr,
124 		    u32 banned_flags);
125 bool inet_rcv_saddr_equal(const struct sock *sk, const struct sock *sk2,
126 			  bool match_wildcard);
127 bool inet_rcv_saddr_any(const struct sock *sk);
128 void addrconf_join_solict(struct net_device *dev, const struct in6_addr *addr);
129 void addrconf_leave_solict(struct inet6_dev *idev, const struct in6_addr *addr);
130 
131 void addrconf_add_linklocal(struct inet6_dev *idev,
132 			    const struct in6_addr *addr, u32 flags);
133 
134 int addrconf_prefix_rcv_add_addr(struct net *net, struct net_device *dev,
135 				 const struct prefix_info *pinfo,
136 				 struct inet6_dev *in6_dev,
137 				 const struct in6_addr *addr, int addr_type,
138 				 u32 addr_flags, bool sllao, bool tokenized,
139 				 __u32 valid_lft, u32 prefered_lft);
140 
141 static inline void addrconf_addr_eui48_base(u8 *eui, const char *const addr)
142 {
143 	memcpy(eui, addr, 3);
144 	eui[3] = 0xFF;
145 	eui[4] = 0xFE;
146 	memcpy(eui + 5, addr + 3, 3);
147 }
148 
149 static inline void addrconf_addr_eui48(u8 *eui, const char *const addr)
150 {
151 	addrconf_addr_eui48_base(eui, addr);
152 	eui[0] ^= 2;
153 }
154 
155 static inline int addrconf_ifid_eui48(u8 *eui, struct net_device *dev)
156 {
157 	if (dev->addr_len != ETH_ALEN)
158 		return -1;
159 
160 	/*
161 	 * The zSeries OSA network cards can be shared among various
162 	 * OS instances, but the OSA cards have only one MAC address.
163 	 * This leads to duplicate address conflicts in conjunction
164 	 * with IPv6 if more than one instance uses the same card.
165 	 *
166 	 * The driver for these cards can deliver a unique 16-bit
167 	 * identifier for each instance sharing the same card.  It is
168 	 * placed instead of 0xFFFE in the interface identifier.  The
169 	 * "u" bit of the interface identifier is not inverted in this
170 	 * case.  Hence the resulting interface identifier has local
171 	 * scope according to RFC2373.
172 	 */
173 
174 	addrconf_addr_eui48_base(eui, dev->dev_addr);
175 
176 	if (dev->dev_id) {
177 		eui[3] = (dev->dev_id >> 8) & 0xFF;
178 		eui[4] = dev->dev_id & 0xFF;
179 	} else {
180 		eui[0] ^= 2;
181 	}
182 
183 	return 0;
184 }
185 
186 static inline unsigned long addrconf_timeout_fixup(u32 timeout,
187 						   unsigned int unit)
188 {
189 	if (timeout == 0xffffffff)
190 		return ~0UL;
191 
192 	/*
193 	 * Avoid arithmetic overflow.
194 	 * Assuming unit is constant and non-zero, this "if" statement
195 	 * will go away on 64bit archs.
196 	 */
197 	if (0xfffffffe > LONG_MAX / unit && timeout > LONG_MAX / unit)
198 		return LONG_MAX / unit;
199 
200 	return timeout;
201 }
202 
203 static inline int addrconf_finite_timeout(unsigned long timeout)
204 {
205 	return ~timeout;
206 }
207 
208 /*
209  *	IPv6 Address Label subsystem (addrlabel.c)
210  */
211 int ipv6_addr_label_init(void);
212 void ipv6_addr_label_cleanup(void);
213 int ipv6_addr_label_rtnl_register(void);
214 u32 ipv6_addr_label(struct net *net, const struct in6_addr *addr,
215 		    int type, int ifindex);
216 
217 /*
218  *	multicast prototypes (mcast.c)
219  */
220 static inline bool ipv6_mc_may_pull(struct sk_buff *skb,
221 				    unsigned int len)
222 {
223 	if (skb_transport_offset(skb) + ipv6_transport_len(skb) < len)
224 		return false;
225 
226 	return pskb_may_pull(skb, len);
227 }
228 
229 int ipv6_sock_mc_join(struct sock *sk, int ifindex,
230 		      const struct in6_addr *addr);
231 int ipv6_sock_mc_drop(struct sock *sk, int ifindex,
232 		      const struct in6_addr *addr);
233 void __ipv6_sock_mc_close(struct sock *sk);
234 void ipv6_sock_mc_close(struct sock *sk);
235 bool inet6_mc_check(const struct sock *sk, const struct in6_addr *mc_addr,
236 		    const struct in6_addr *src_addr);
237 
238 int ipv6_dev_mc_inc(struct net_device *dev, const struct in6_addr *addr);
239 int __ipv6_dev_mc_dec(struct inet6_dev *idev, const struct in6_addr *addr);
240 int ipv6_dev_mc_dec(struct net_device *dev, const struct in6_addr *addr);
241 void ipv6_mc_up(struct inet6_dev *idev);
242 void ipv6_mc_down(struct inet6_dev *idev);
243 void ipv6_mc_unmap(struct inet6_dev *idev);
244 void ipv6_mc_remap(struct inet6_dev *idev);
245 void ipv6_mc_init_dev(struct inet6_dev *idev);
246 void ipv6_mc_destroy_dev(struct inet6_dev *idev);
247 int ipv6_mc_check_mld(struct sk_buff *skb);
248 void addrconf_dad_failure(struct sk_buff *skb, struct inet6_ifaddr *ifp);
249 
250 bool ipv6_chk_mcast_addr(struct net_device *dev, const struct in6_addr *group,
251 			 const struct in6_addr *src_addr);
252 
253 void ipv6_mc_dad_complete(struct inet6_dev *idev);
254 
255 /*
256  * identify MLD packets for MLD filter exceptions
257  */
258 static inline bool ipv6_is_mld(struct sk_buff *skb, int nexthdr, int offset)
259 {
260 	struct icmp6hdr *hdr;
261 
262 	if (nexthdr != IPPROTO_ICMPV6 ||
263 	    !pskb_network_may_pull(skb, offset + sizeof(struct icmp6hdr)))
264 		return false;
265 
266 	hdr = (struct icmp6hdr *)(skb_network_header(skb) + offset);
267 
268 	switch (hdr->icmp6_type) {
269 	case ICMPV6_MGM_QUERY:
270 	case ICMPV6_MGM_REPORT:
271 	case ICMPV6_MGM_REDUCTION:
272 	case ICMPV6_MLD2_REPORT:
273 		return true;
274 	default:
275 		break;
276 	}
277 	return false;
278 }
279 
280 void addrconf_prefix_rcv(struct net_device *dev,
281 			 u8 *opt, int len, bool sllao);
282 
283 /*
284  *	anycast prototypes (anycast.c)
285  */
286 int ipv6_sock_ac_join(struct sock *sk, int ifindex,
287 		      const struct in6_addr *addr);
288 int ipv6_sock_ac_drop(struct sock *sk, int ifindex,
289 		      const struct in6_addr *addr);
290 void __ipv6_sock_ac_close(struct sock *sk);
291 void ipv6_sock_ac_close(struct sock *sk);
292 
293 int __ipv6_dev_ac_inc(struct inet6_dev *idev, const struct in6_addr *addr);
294 int __ipv6_dev_ac_dec(struct inet6_dev *idev, const struct in6_addr *addr);
295 void ipv6_ac_destroy_dev(struct inet6_dev *idev);
296 bool ipv6_chk_acast_addr(struct net *net, struct net_device *dev,
297 			 const struct in6_addr *addr);
298 bool ipv6_chk_acast_addr_src(struct net *net, struct net_device *dev,
299 			     const struct in6_addr *addr);
300 int ipv6_anycast_init(void);
301 void ipv6_anycast_cleanup(void);
302 
303 /* Device notifier */
304 int register_inet6addr_notifier(struct notifier_block *nb);
305 int unregister_inet6addr_notifier(struct notifier_block *nb);
306 int inet6addr_notifier_call_chain(unsigned long val, void *v);
307 
308 int register_inet6addr_validator_notifier(struct notifier_block *nb);
309 int unregister_inet6addr_validator_notifier(struct notifier_block *nb);
310 int inet6addr_validator_notifier_call_chain(unsigned long val, void *v);
311 
312 void inet6_netconf_notify_devconf(struct net *net, int event, int type,
313 				  int ifindex, struct ipv6_devconf *devconf);
314 
315 /**
316  * __in6_dev_get - get inet6_dev pointer from netdevice
317  * @dev: network device
318  *
319  * Caller must hold rcu_read_lock or RTNL, because this function
320  * does not take a reference on the inet6_dev.
321  */
322 static inline struct inet6_dev *__in6_dev_get(const struct net_device *dev)
323 {
324 	return rcu_dereference_rtnl(dev->ip6_ptr);
325 }
326 
327 /**
328  * __in6_dev_stats_get - get inet6_dev pointer for stats
329  * @dev: network device
330  * @skb: skb for original incoming interface if neeeded
331  *
332  * Caller must hold rcu_read_lock or RTNL, because this function
333  * does not take a reference on the inet6_dev.
334  */
335 static inline struct inet6_dev *__in6_dev_stats_get(const struct net_device *dev,
336 						    const struct sk_buff *skb)
337 {
338 	if (netif_is_l3_master(dev))
339 		dev = dev_get_by_index_rcu(dev_net(dev), inet6_iif(skb));
340 	return __in6_dev_get(dev);
341 }
342 
343 /**
344  * __in6_dev_get_safely - get inet6_dev pointer from netdevice
345  * @dev: network device
346  *
347  * This is a safer version of __in6_dev_get
348  */
349 static inline struct inet6_dev *__in6_dev_get_safely(const struct net_device *dev)
350 {
351 	if (likely(dev))
352 		return rcu_dereference_rtnl(dev->ip6_ptr);
353 	else
354 		return NULL;
355 }
356 
357 /**
358  * in6_dev_get - get inet6_dev pointer from netdevice
359  * @dev: network device
360  *
361  * This version can be used in any context, and takes a reference
362  * on the inet6_dev. Callers must use in6_dev_put() later to
363  * release this reference.
364  */
365 static inline struct inet6_dev *in6_dev_get(const struct net_device *dev)
366 {
367 	struct inet6_dev *idev;
368 
369 	rcu_read_lock();
370 	idev = rcu_dereference(dev->ip6_ptr);
371 	if (idev)
372 		refcount_inc(&idev->refcnt);
373 	rcu_read_unlock();
374 	return idev;
375 }
376 
377 static inline struct neigh_parms *__in6_dev_nd_parms_get_rcu(const struct net_device *dev)
378 {
379 	struct inet6_dev *idev = __in6_dev_get(dev);
380 
381 	return idev ? idev->nd_parms : NULL;
382 }
383 
384 void in6_dev_finish_destroy(struct inet6_dev *idev);
385 
386 static inline void in6_dev_put(struct inet6_dev *idev)
387 {
388 	if (refcount_dec_and_test(&idev->refcnt))
389 		in6_dev_finish_destroy(idev);
390 }
391 
392 static inline void in6_dev_put_clear(struct inet6_dev **pidev)
393 {
394 	struct inet6_dev *idev = *pidev;
395 
396 	if (idev) {
397 		in6_dev_put(idev);
398 		*pidev = NULL;
399 	}
400 }
401 
402 static inline void __in6_dev_put(struct inet6_dev *idev)
403 {
404 	refcount_dec(&idev->refcnt);
405 }
406 
407 static inline void in6_dev_hold(struct inet6_dev *idev)
408 {
409 	refcount_inc(&idev->refcnt);
410 }
411 
412 /* called with rcu_read_lock held */
413 static inline bool ip6_ignore_linkdown(const struct net_device *dev)
414 {
415 	const struct inet6_dev *idev = __in6_dev_get(dev);
416 
417 	if (unlikely(!idev))
418 		return true;
419 
420 	return !!READ_ONCE(idev->cnf.ignore_routes_with_linkdown);
421 }
422 
423 void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp);
424 
425 static inline void in6_ifa_put(struct inet6_ifaddr *ifp)
426 {
427 	if (refcount_dec_and_test(&ifp->refcnt))
428 		inet6_ifa_finish_destroy(ifp);
429 }
430 
431 static inline void __in6_ifa_put(struct inet6_ifaddr *ifp)
432 {
433 	refcount_dec(&ifp->refcnt);
434 }
435 
436 static inline void in6_ifa_hold(struct inet6_ifaddr *ifp)
437 {
438 	refcount_inc(&ifp->refcnt);
439 }
440 
441 static inline bool in6_ifa_hold_safe(struct inet6_ifaddr *ifp)
442 {
443 	return refcount_inc_not_zero(&ifp->refcnt);
444 }
445 
446 /*
447  *	compute link-local solicited-node multicast address
448  */
449 
450 static inline void addrconf_addr_solict_mult(const struct in6_addr *addr,
451 					     struct in6_addr *solicited)
452 {
453 	ipv6_addr_set(solicited,
454 		      htonl(0xFF020000), 0,
455 		      htonl(0x1),
456 		      htonl(0xFF000000) | addr->s6_addr32[3]);
457 }
458 
459 static inline bool ipv6_addr_is_ll_all_nodes(const struct in6_addr *addr)
460 {
461 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
462 	__be64 *p = (__force __be64 *)addr;
463 	return ((p[0] ^ cpu_to_be64(0xff02000000000000UL)) | (p[1] ^ cpu_to_be64(1))) == 0UL;
464 #else
465 	return ((addr->s6_addr32[0] ^ htonl(0xff020000)) |
466 		addr->s6_addr32[1] | addr->s6_addr32[2] |
467 		(addr->s6_addr32[3] ^ htonl(0x00000001))) == 0;
468 #endif
469 }
470 
471 static inline bool ipv6_addr_is_ll_all_routers(const struct in6_addr *addr)
472 {
473 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
474 	__be64 *p = (__force __be64 *)addr;
475 	return ((p[0] ^ cpu_to_be64(0xff02000000000000UL)) | (p[1] ^ cpu_to_be64(2))) == 0UL;
476 #else
477 	return ((addr->s6_addr32[0] ^ htonl(0xff020000)) |
478 		addr->s6_addr32[1] | addr->s6_addr32[2] |
479 		(addr->s6_addr32[3] ^ htonl(0x00000002))) == 0;
480 #endif
481 }
482 
483 static inline bool ipv6_addr_is_isatap(const struct in6_addr *addr)
484 {
485 	return (addr->s6_addr32[2] | htonl(0x02000000)) == htonl(0x02005EFE);
486 }
487 
488 static inline bool ipv6_addr_is_solict_mult(const struct in6_addr *addr)
489 {
490 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
491 	__be64 *p = (__force __be64 *)addr;
492 	return ((p[0] ^ cpu_to_be64(0xff02000000000000UL)) |
493 		((p[1] ^ cpu_to_be64(0x00000001ff000000UL)) &
494 		 cpu_to_be64(0xffffffffff000000UL))) == 0UL;
495 #else
496 	return ((addr->s6_addr32[0] ^ htonl(0xff020000)) |
497 		addr->s6_addr32[1] |
498 		(addr->s6_addr32[2] ^ htonl(0x00000001)) |
499 		(addr->s6_addr[12] ^ 0xff)) == 0;
500 #endif
501 }
502 
503 static inline bool ipv6_addr_is_all_snoopers(const struct in6_addr *addr)
504 {
505 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
506 	__be64 *p = (__force __be64 *)addr;
507 
508 	return ((p[0] ^ cpu_to_be64(0xff02000000000000UL)) |
509 		(p[1] ^ cpu_to_be64(0x6a))) == 0UL;
510 #else
511 	return ((addr->s6_addr32[0] ^ htonl(0xff020000)) |
512 		addr->s6_addr32[1] | addr->s6_addr32[2] |
513 		(addr->s6_addr32[3] ^ htonl(0x0000006a))) == 0;
514 #endif
515 }
516 
517 #ifdef CONFIG_PROC_FS
518 int if6_proc_init(void);
519 void if6_proc_exit(void);
520 #endif
521 
522 #endif
523