xref: /linux/include/net/addrconf.h (revision 69050f8d6d075dc01af7a5f2f550a8067510366f)
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 /* TEMP_VALID_LIFETIME default value as specified in RFC 8981 3.8 */
12 #define TEMP_VALID_LIFETIME		(2*86400)       /* 2 days */
13 #define TEMP_PREFERRED_LIFETIME		(86400)         /* 24 hours */
14 #define REGEN_MIN_ADVANCE		(2)             /* 2 seconds */
15 #define REGEN_MAX_RETRY			(3)
16 #define MAX_DESYNC_FACTOR		(600)
17 
18 #define ADDR_CHECK_FREQUENCY		(120*HZ)
19 
20 #define IPV6_MAX_ADDRESSES		16
21 
22 #define ADDRCONF_TIMER_FUZZ_MINUS	(HZ > 50 ? HZ / 50 : 1)
23 #define ADDRCONF_TIMER_FUZZ		(HZ / 4)
24 #define ADDRCONF_TIMER_FUZZ_MAX		(HZ)
25 
26 #define ADDRCONF_NOTIFY_PRIORITY	0
27 
28 #include <linux/in.h>
29 #include <linux/in6.h>
30 
31 struct prefix_info {
32 	__u8			type;
33 	__u8			length;
34 	__u8			prefix_len;
35 
36 	union __packed {
37 		__u8		flags;
38 		struct __packed {
39 #if defined(__BIG_ENDIAN_BITFIELD)
40 			__u8	onlink : 1,
41 				autoconf : 1,
42 				routeraddr : 1,
43 				preferpd : 1,
44 				reserved : 4;
45 #elif defined(__LITTLE_ENDIAN_BITFIELD)
46 			__u8	reserved : 4,
47 				preferpd : 1,
48 				routeraddr : 1,
49 				autoconf : 1,
50 				onlink : 1;
51 #else
52 #error "Please fix <asm/byteorder.h>"
53 #endif
54 		};
55 	};
56 	__be32			valid;
57 	__be32			prefered;
58 	__be32			reserved2;
59 
60 	struct in6_addr		prefix;
61 };
62 
63 /* rfc4861 4.6.2: IPv6 PIO is 32 bytes in size */
64 static_assert(sizeof(struct prefix_info) == 32);
65 
66 #include <linux/ipv6.h>
67 #include <linux/netdevice.h>
68 #include <net/if_inet6.h>
69 #include <net/ipv6.h>
70 
71 struct in6_validator_info {
72 	struct in6_addr		i6vi_addr;
73 	struct inet6_dev	*i6vi_dev;
74 	struct netlink_ext_ack	*extack;
75 };
76 
77 struct ifa6_config {
78 	const struct in6_addr	*pfx;
79 	unsigned int		plen;
80 
81 	u8			ifa_proto;
82 
83 	const struct in6_addr	*peer_pfx;
84 
85 	u32			rt_priority;
86 	u32			ifa_flags;
87 	u32			preferred_lft;
88 	u32			valid_lft;
89 	u16			scope;
90 };
91 
92 enum addr_type_t {
93 	UNICAST_ADDR,
94 	MULTICAST_ADDR,
95 	ANYCAST_ADDR,
96 };
97 
98 struct inet6_fill_args {
99 	u32 portid;
100 	u32 seq;
101 	int event;
102 	unsigned int flags;
103 	int netnsid;
104 	int ifindex;
105 	enum addr_type_t type;
106 	bool force_rt_scope_universe;
107 };
108 
109 int addrconf_init(void);
110 void addrconf_cleanup(void);
111 
112 int addrconf_add_ifaddr(struct net *net, void __user *arg);
113 int addrconf_del_ifaddr(struct net *net, void __user *arg);
114 int addrconf_set_dstaddr(struct net *net, void __user *arg);
115 
116 int ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
117 		  const struct net_device *dev, int strict);
118 int ipv6_chk_addr_and_flags(struct net *net, const struct in6_addr *addr,
119 			    const struct net_device *dev, bool skip_dev_check,
120 			    int strict, u32 banned_flags);
121 
122 #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
123 int ipv6_chk_home_addr(struct net *net, const struct in6_addr *addr);
124 #endif
125 
126 int ipv6_chk_rpl_srh_loop(struct net *net, const struct in6_addr *segs,
127 			  unsigned char nsegs);
128 
129 bool ipv6_chk_custom_prefix(const struct in6_addr *addr,
130 				   const unsigned int prefix_len,
131 				   struct net_device *dev);
132 
133 int ipv6_chk_prefix(const struct in6_addr *addr, struct net_device *dev);
134 
135 struct net_device *ipv6_dev_find(struct net *net, const struct in6_addr *addr,
136 				 struct net_device *dev);
137 
138 struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net,
139 				     const struct in6_addr *addr,
140 				     struct net_device *dev, int strict);
141 
142 int ipv6_dev_get_saddr(struct net *net, const struct net_device *dev,
143 		       const struct in6_addr *daddr, unsigned int srcprefs,
144 		       struct in6_addr *saddr);
145 int ipv6_get_lladdr(struct net_device *dev, struct in6_addr *addr,
146 		    u32 banned_flags);
147 bool inet_rcv_saddr_equal(const struct sock *sk, const struct sock *sk2,
148 			  bool match_wildcard);
149 bool inet_rcv_saddr_any(const struct sock *sk);
150 void addrconf_join_solict(struct net_device *dev, const struct in6_addr *addr);
151 void addrconf_leave_solict(struct inet6_dev *idev, const struct in6_addr *addr);
152 
153 void addrconf_add_linklocal(struct inet6_dev *idev,
154 			    const struct in6_addr *addr, u32 flags);
155 
156 int addrconf_prefix_rcv_add_addr(struct net *net, struct net_device *dev,
157 				 const struct prefix_info *pinfo,
158 				 struct inet6_dev *in6_dev,
159 				 const struct in6_addr *addr, int addr_type,
160 				 u32 addr_flags, bool sllao, bool tokenized,
161 				 __u32 valid_lft, u32 prefered_lft);
162 
163 static inline void addrconf_addr_eui48_base(u8 *eui, const char *const addr)
164 {
165 	memcpy(eui, addr, 3);
166 	eui[3] = 0xFF;
167 	eui[4] = 0xFE;
168 	memcpy(eui + 5, addr + 3, 3);
169 }
170 
171 static inline void addrconf_addr_eui48(u8 *eui, const char *const addr)
172 {
173 	addrconf_addr_eui48_base(eui, addr);
174 	eui[0] ^= 2;
175 }
176 
177 static inline int addrconf_ifid_eui48(u8 *eui, struct net_device *dev)
178 {
179 	if (dev->addr_len != ETH_ALEN)
180 		return -1;
181 
182 	/*
183 	 * The zSeries OSA network cards can be shared among various
184 	 * OS instances, but the OSA cards have only one MAC address.
185 	 * This leads to duplicate address conflicts in conjunction
186 	 * with IPv6 if more than one instance uses the same card.
187 	 *
188 	 * The driver for these cards can deliver a unique 16-bit
189 	 * identifier for each instance sharing the same card.  It is
190 	 * placed instead of 0xFFFE in the interface identifier.  The
191 	 * "u" bit of the interface identifier is not inverted in this
192 	 * case.  Hence the resulting interface identifier has local
193 	 * scope according to RFC2373.
194 	 */
195 
196 	addrconf_addr_eui48_base(eui, dev->dev_addr);
197 
198 	if (dev->dev_id) {
199 		eui[3] = (dev->dev_id >> 8) & 0xFF;
200 		eui[4] = dev->dev_id & 0xFF;
201 	} else {
202 		eui[0] ^= 2;
203 	}
204 
205 	return 0;
206 }
207 
208 #define INFINITY_LIFE_TIME 0xFFFFFFFF
209 
210 static inline unsigned long addrconf_timeout_fixup(u32 timeout,
211 						   unsigned int unit)
212 {
213 	if (timeout == INFINITY_LIFE_TIME)
214 		return ~0UL;
215 
216 	/*
217 	 * Avoid arithmetic overflow.
218 	 * Assuming unit is constant and non-zero, this "if" statement
219 	 * will go away on 64bit archs.
220 	 */
221 	if (0xfffffffe > LONG_MAX / unit && timeout > LONG_MAX / unit)
222 		return LONG_MAX / unit;
223 
224 	return timeout;
225 }
226 
227 static inline int addrconf_finite_timeout(unsigned long timeout)
228 {
229 	return ~timeout;
230 }
231 
232 /*
233  *	IPv6 Address Label subsystem (addrlabel.c)
234  */
235 int ipv6_addr_label_init(void);
236 void ipv6_addr_label_cleanup(void);
237 int ipv6_addr_label_rtnl_register(void);
238 u32 ipv6_addr_label(struct net *net, const struct in6_addr *addr,
239 		    int type, int ifindex);
240 
241 /*
242  *	multicast prototypes (mcast.c)
243  */
244 static inline bool ipv6_mc_may_pull(struct sk_buff *skb,
245 				    unsigned int len)
246 {
247 	if (skb_transport_offset(skb) + ipv6_transport_len(skb) < len)
248 		return false;
249 
250 	return pskb_may_pull(skb, len);
251 }
252 
253 int ipv6_sock_mc_join(struct sock *sk, int ifindex,
254 		      const struct in6_addr *addr);
255 int ipv6_sock_mc_drop(struct sock *sk, int ifindex,
256 		      const struct in6_addr *addr);
257 void __ipv6_sock_mc_close(struct sock *sk);
258 void ipv6_sock_mc_close(struct sock *sk);
259 bool inet6_mc_check(const struct sock *sk, const struct in6_addr *mc_addr,
260 		    const struct in6_addr *src_addr);
261 
262 int ipv6_dev_mc_inc(struct net_device *dev, const struct in6_addr *addr);
263 int __ipv6_dev_mc_dec(struct inet6_dev *idev, const struct in6_addr *addr);
264 int ipv6_dev_mc_dec(struct net_device *dev, const struct in6_addr *addr);
265 void ipv6_mc_up(struct inet6_dev *idev);
266 void ipv6_mc_down(struct inet6_dev *idev);
267 void ipv6_mc_unmap(struct inet6_dev *idev);
268 void ipv6_mc_remap(struct inet6_dev *idev);
269 void ipv6_mc_init_dev(struct inet6_dev *idev);
270 void ipv6_mc_destroy_dev(struct inet6_dev *idev);
271 int ipv6_mc_check_mld(struct sk_buff *skb);
272 void addrconf_dad_failure(struct sk_buff *skb, struct inet6_ifaddr *ifp);
273 
274 bool ipv6_chk_mcast_addr(struct net_device *dev, const struct in6_addr *group,
275 			 const struct in6_addr *src_addr);
276 
277 void ipv6_mc_dad_complete(struct inet6_dev *idev);
278 
279 /*
280  * identify MLD packets for MLD filter exceptions
281  */
282 static inline bool ipv6_is_mld(struct sk_buff *skb, int nexthdr, int offset)
283 {
284 	struct icmp6hdr *hdr;
285 
286 	if (nexthdr != IPPROTO_ICMPV6 ||
287 	    !pskb_network_may_pull(skb, offset + sizeof(struct icmp6hdr)))
288 		return false;
289 
290 	hdr = (struct icmp6hdr *)(skb_network_header(skb) + offset);
291 
292 	switch (hdr->icmp6_type) {
293 	case ICMPV6_MGM_QUERY:
294 	case ICMPV6_MGM_REPORT:
295 	case ICMPV6_MGM_REDUCTION:
296 	case ICMPV6_MLD2_REPORT:
297 		return true;
298 	default:
299 		break;
300 	}
301 	return false;
302 }
303 
304 void addrconf_prefix_rcv(struct net_device *dev,
305 			 u8 *opt, int len, bool sllao);
306 
307 /*
308  *	anycast prototypes (anycast.c)
309  */
310 int ipv6_sock_ac_join(struct sock *sk, int ifindex,
311 		      const struct in6_addr *addr);
312 int ipv6_sock_ac_drop(struct sock *sk, int ifindex,
313 		      const struct in6_addr *addr);
314 void __ipv6_sock_ac_close(struct sock *sk);
315 void ipv6_sock_ac_close(struct sock *sk);
316 
317 int __ipv6_dev_ac_inc(struct inet6_dev *idev, const struct in6_addr *addr);
318 int __ipv6_dev_ac_dec(struct inet6_dev *idev, const struct in6_addr *addr);
319 void ipv6_ac_destroy_dev(struct inet6_dev *idev);
320 bool ipv6_chk_acast_addr(struct net *net, struct net_device *dev,
321 			 const struct in6_addr *addr);
322 bool ipv6_chk_acast_addr_src(struct net *net, struct net_device *dev,
323 			     const struct in6_addr *addr);
324 int ipv6_anycast_init(void);
325 void ipv6_anycast_cleanup(void);
326 
327 /* Device notifier */
328 int register_inet6addr_notifier(struct notifier_block *nb);
329 int unregister_inet6addr_notifier(struct notifier_block *nb);
330 int inet6addr_notifier_call_chain(unsigned long val, void *v);
331 
332 int register_inet6addr_validator_notifier(struct notifier_block *nb);
333 int unregister_inet6addr_validator_notifier(struct notifier_block *nb);
334 int inet6addr_validator_notifier_call_chain(unsigned long val, void *v);
335 
336 void inet6_netconf_notify_devconf(struct net *net, int event, int type,
337 				  int ifindex, struct ipv6_devconf *devconf);
338 
339 /**
340  * __in6_dev_get - get inet6_dev pointer from netdevice
341  * @dev: network device
342  *
343  * Caller must hold rcu_read_lock or RTNL, because this function
344  * does not take a reference on the inet6_dev.
345  */
346 static inline struct inet6_dev *__in6_dev_get(const struct net_device *dev)
347 {
348 	return rcu_dereference_rtnl(dev->ip6_ptr);
349 }
350 
351 static inline struct inet6_dev *in6_dev_rcu(const struct net_device *dev)
352 {
353 	return rcu_dereference(dev->ip6_ptr);
354 }
355 
356 static inline struct inet6_dev *__in6_dev_get_rtnl_net(const struct net_device *dev)
357 {
358 	return rtnl_net_dereference(dev_net(dev), dev->ip6_ptr);
359 }
360 
361 /**
362  * __in6_dev_stats_get - get inet6_dev pointer for stats
363  * @dev: network device
364  * @skb: skb for original incoming interface if needed
365  *
366  * Caller must hold rcu_read_lock or RTNL, because this function
367  * does not take a reference on the inet6_dev.
368  */
369 static inline struct inet6_dev *__in6_dev_stats_get(const struct net_device *dev,
370 						    const struct sk_buff *skb)
371 {
372 	if (netif_is_l3_master(dev))
373 		dev = dev_get_by_index_rcu(dev_net(dev), inet6_iif(skb));
374 	return __in6_dev_get(dev);
375 }
376 
377 /**
378  * __in6_dev_get_safely - get inet6_dev pointer from netdevice
379  * @dev: network device
380  *
381  * This is a safer version of __in6_dev_get
382  */
383 static inline struct inet6_dev *__in6_dev_get_safely(const struct net_device *dev)
384 {
385 	if (likely(dev))
386 		return rcu_dereference_rtnl(dev->ip6_ptr);
387 	else
388 		return NULL;
389 }
390 
391 /**
392  * in6_dev_get - get inet6_dev pointer from netdevice
393  * @dev: network device
394  *
395  * This version can be used in any context, and takes a reference
396  * on the inet6_dev. Callers must use in6_dev_put() later to
397  * release this reference.
398  */
399 static inline struct inet6_dev *in6_dev_get(const struct net_device *dev)
400 {
401 	struct inet6_dev *idev;
402 
403 	rcu_read_lock();
404 	idev = rcu_dereference(dev->ip6_ptr);
405 	if (idev)
406 		refcount_inc(&idev->refcnt);
407 	rcu_read_unlock();
408 	return idev;
409 }
410 
411 static inline struct neigh_parms *__in6_dev_nd_parms_get_rcu(const struct net_device *dev)
412 {
413 	struct inet6_dev *idev = __in6_dev_get(dev);
414 
415 	return idev ? idev->nd_parms : NULL;
416 }
417 
418 void in6_dev_finish_destroy(struct inet6_dev *idev);
419 
420 static inline void in6_dev_put(struct inet6_dev *idev)
421 {
422 	if (refcount_dec_and_test(&idev->refcnt))
423 		in6_dev_finish_destroy(idev);
424 }
425 
426 static inline void in6_dev_put_clear(struct inet6_dev **pidev)
427 {
428 	struct inet6_dev *idev = *pidev;
429 
430 	if (idev) {
431 		in6_dev_put(idev);
432 		*pidev = NULL;
433 	}
434 }
435 
436 static inline void __in6_dev_put(struct inet6_dev *idev)
437 {
438 	refcount_dec(&idev->refcnt);
439 }
440 
441 static inline void in6_dev_hold(struct inet6_dev *idev)
442 {
443 	refcount_inc(&idev->refcnt);
444 }
445 
446 /* called with rcu_read_lock held */
447 static inline bool ip6_ignore_linkdown(const struct net_device *dev)
448 {
449 	const struct inet6_dev *idev = __in6_dev_get(dev);
450 
451 	if (unlikely(!idev))
452 		return true;
453 
454 	return !!READ_ONCE(idev->cnf.ignore_routes_with_linkdown);
455 }
456 
457 void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp);
458 
459 static inline void in6_ifa_put(struct inet6_ifaddr *ifp)
460 {
461 	if (refcount_dec_and_test(&ifp->refcnt))
462 		inet6_ifa_finish_destroy(ifp);
463 }
464 
465 static inline void __in6_ifa_put(struct inet6_ifaddr *ifp)
466 {
467 	refcount_dec(&ifp->refcnt);
468 }
469 
470 static inline void in6_ifa_hold(struct inet6_ifaddr *ifp)
471 {
472 	refcount_inc(&ifp->refcnt);
473 }
474 
475 static inline bool in6_ifa_hold_safe(struct inet6_ifaddr *ifp)
476 {
477 	return refcount_inc_not_zero(&ifp->refcnt);
478 }
479 
480 /*
481  *	compute link-local solicited-node multicast address
482  */
483 
484 static inline void addrconf_addr_solict_mult(const struct in6_addr *addr,
485 					     struct in6_addr *solicited)
486 {
487 	ipv6_addr_set(solicited,
488 		      htonl(0xFF020000), 0,
489 		      htonl(0x1),
490 		      htonl(0xFF000000) | addr->s6_addr32[3]);
491 }
492 
493 static inline bool ipv6_addr_is_ll_all_nodes(const struct in6_addr *addr)
494 {
495 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
496 	__be64 *p = (__force __be64 *)addr;
497 	return ((p[0] ^ cpu_to_be64(0xff02000000000000UL)) | (p[1] ^ cpu_to_be64(1))) == 0UL;
498 #else
499 	return ((addr->s6_addr32[0] ^ htonl(0xff020000)) |
500 		addr->s6_addr32[1] | addr->s6_addr32[2] |
501 		(addr->s6_addr32[3] ^ htonl(0x00000001))) == 0;
502 #endif
503 }
504 
505 static inline bool ipv6_addr_is_ll_all_routers(const struct in6_addr *addr)
506 {
507 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
508 	__be64 *p = (__force __be64 *)addr;
509 	return ((p[0] ^ cpu_to_be64(0xff02000000000000UL)) | (p[1] ^ cpu_to_be64(2))) == 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(0x00000002))) == 0;
514 #endif
515 }
516 
517 static inline bool ipv6_addr_is_isatap(const struct in6_addr *addr)
518 {
519 	return (addr->s6_addr32[2] | htonl(0x02000000)) == htonl(0x02005EFE);
520 }
521 
522 static inline bool ipv6_addr_is_solict_mult(const struct in6_addr *addr)
523 {
524 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
525 	__be64 *p = (__force __be64 *)addr;
526 	return ((p[0] ^ cpu_to_be64(0xff02000000000000UL)) |
527 		((p[1] ^ cpu_to_be64(0x00000001ff000000UL)) &
528 		 cpu_to_be64(0xffffffffff000000UL))) == 0UL;
529 #else
530 	return ((addr->s6_addr32[0] ^ htonl(0xff020000)) |
531 		addr->s6_addr32[1] |
532 		(addr->s6_addr32[2] ^ htonl(0x00000001)) |
533 		(addr->s6_addr[12] ^ 0xff)) == 0;
534 #endif
535 }
536 
537 static inline bool ipv6_addr_is_all_snoopers(const struct in6_addr *addr)
538 {
539 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
540 	__be64 *p = (__force __be64 *)addr;
541 
542 	return ((p[0] ^ cpu_to_be64(0xff02000000000000UL)) |
543 		(p[1] ^ cpu_to_be64(0x6a))) == 0UL;
544 #else
545 	return ((addr->s6_addr32[0] ^ htonl(0xff020000)) |
546 		addr->s6_addr32[1] | addr->s6_addr32[2] |
547 		(addr->s6_addr32[3] ^ htonl(0x0000006a))) == 0;
548 #endif
549 }
550 
551 #ifdef CONFIG_PROC_FS
552 int if6_proc_init(void);
553 void if6_proc_exit(void);
554 #endif
555 
556 int inet6_fill_ifmcaddr(struct sk_buff *skb,
557 			const struct ifmcaddr6 *ifmca,
558 			struct inet6_fill_args *args);
559 
560 int inet6_fill_ifacaddr(struct sk_buff *skb,
561 			const struct ifacaddr6 *ifaca,
562 			struct inet6_fill_args *args);
563 #endif
564