xref: /linux/include/net/addrconf.h (revision 46e6acfe3501fa938af9c5bd730f0020235b08a2)
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 				routeraddr : 1,
42 				preferpd : 1,
43 				reserved : 4;
44 #elif defined(__LITTLE_ENDIAN_BITFIELD)
45 			__u8	reserved : 4,
46 				preferpd : 1,
47 				routeraddr : 1,
48 				autoconf : 1,
49 				onlink : 1;
50 #else
51 #error "Please fix <asm/byteorder.h>"
52 #endif
53 		};
54 	};
55 	__be32			valid;
56 	__be32			prefered;
57 	__be32			reserved2;
58 
59 	struct in6_addr		prefix;
60 };
61 
62 /* rfc4861 4.6.2: IPv6 PIO is 32 bytes in size */
63 static_assert(sizeof(struct prefix_info) == 32);
64 
65 #include <linux/ipv6.h>
66 #include <linux/netdevice.h>
67 #include <net/if_inet6.h>
68 #include <net/ipv6.h>
69 
70 struct in6_validator_info {
71 	struct in6_addr		i6vi_addr;
72 	struct inet6_dev	*i6vi_dev;
73 	struct netlink_ext_ack	*extack;
74 };
75 
76 struct ifa6_config {
77 	const struct in6_addr	*pfx;
78 	unsigned int		plen;
79 
80 	u8			ifa_proto;
81 
82 	const struct in6_addr	*peer_pfx;
83 
84 	u32			rt_priority;
85 	u32			ifa_flags;
86 	u32			preferred_lft;
87 	u32			valid_lft;
88 	u16			scope;
89 };
90 
91 int addrconf_init(void);
92 void addrconf_cleanup(void);
93 
94 int addrconf_add_ifaddr(struct net *net, void __user *arg);
95 int addrconf_del_ifaddr(struct net *net, void __user *arg);
96 int addrconf_set_dstaddr(struct net *net, void __user *arg);
97 
98 int ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
99 		  const struct net_device *dev, int strict);
100 int ipv6_chk_addr_and_flags(struct net *net, const struct in6_addr *addr,
101 			    const struct net_device *dev, bool skip_dev_check,
102 			    int strict, u32 banned_flags);
103 
104 #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
105 int ipv6_chk_home_addr(struct net *net, const struct in6_addr *addr);
106 #endif
107 
108 int ipv6_chk_rpl_srh_loop(struct net *net, const struct in6_addr *segs,
109 			  unsigned char nsegs);
110 
111 bool ipv6_chk_custom_prefix(const struct in6_addr *addr,
112 				   const unsigned int prefix_len,
113 				   struct net_device *dev);
114 
115 int ipv6_chk_prefix(const struct in6_addr *addr, struct net_device *dev);
116 
117 struct net_device *ipv6_dev_find(struct net *net, const struct in6_addr *addr,
118 				 struct net_device *dev);
119 
120 struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net,
121 				     const struct in6_addr *addr,
122 				     struct net_device *dev, int strict);
123 
124 int ipv6_dev_get_saddr(struct net *net, const struct net_device *dev,
125 		       const struct in6_addr *daddr, unsigned int srcprefs,
126 		       struct in6_addr *saddr);
127 int ipv6_get_lladdr(struct net_device *dev, struct in6_addr *addr,
128 		    u32 banned_flags);
129 bool inet_rcv_saddr_equal(const struct sock *sk, const struct sock *sk2,
130 			  bool match_wildcard);
131 bool inet_rcv_saddr_any(const struct sock *sk);
132 void addrconf_join_solict(struct net_device *dev, const struct in6_addr *addr);
133 void addrconf_leave_solict(struct inet6_dev *idev, const struct in6_addr *addr);
134 
135 void addrconf_add_linklocal(struct inet6_dev *idev,
136 			    const struct in6_addr *addr, u32 flags);
137 
138 int addrconf_prefix_rcv_add_addr(struct net *net, struct net_device *dev,
139 				 const struct prefix_info *pinfo,
140 				 struct inet6_dev *in6_dev,
141 				 const struct in6_addr *addr, int addr_type,
142 				 u32 addr_flags, bool sllao, bool tokenized,
143 				 __u32 valid_lft, u32 prefered_lft);
144 
145 static inline void addrconf_addr_eui48_base(u8 *eui, const char *const addr)
146 {
147 	memcpy(eui, addr, 3);
148 	eui[3] = 0xFF;
149 	eui[4] = 0xFE;
150 	memcpy(eui + 5, addr + 3, 3);
151 }
152 
153 static inline void addrconf_addr_eui48(u8 *eui, const char *const addr)
154 {
155 	addrconf_addr_eui48_base(eui, addr);
156 	eui[0] ^= 2;
157 }
158 
159 static inline int addrconf_ifid_eui48(u8 *eui, struct net_device *dev)
160 {
161 	if (dev->addr_len != ETH_ALEN)
162 		return -1;
163 
164 	/*
165 	 * The zSeries OSA network cards can be shared among various
166 	 * OS instances, but the OSA cards have only one MAC address.
167 	 * This leads to duplicate address conflicts in conjunction
168 	 * with IPv6 if more than one instance uses the same card.
169 	 *
170 	 * The driver for these cards can deliver a unique 16-bit
171 	 * identifier for each instance sharing the same card.  It is
172 	 * placed instead of 0xFFFE in the interface identifier.  The
173 	 * "u" bit of the interface identifier is not inverted in this
174 	 * case.  Hence the resulting interface identifier has local
175 	 * scope according to RFC2373.
176 	 */
177 
178 	addrconf_addr_eui48_base(eui, dev->dev_addr);
179 
180 	if (dev->dev_id) {
181 		eui[3] = (dev->dev_id >> 8) & 0xFF;
182 		eui[4] = dev->dev_id & 0xFF;
183 	} else {
184 		eui[0] ^= 2;
185 	}
186 
187 	return 0;
188 }
189 
190 static inline unsigned long addrconf_timeout_fixup(u32 timeout,
191 						   unsigned int unit)
192 {
193 	if (timeout == 0xffffffff)
194 		return ~0UL;
195 
196 	/*
197 	 * Avoid arithmetic overflow.
198 	 * Assuming unit is constant and non-zero, this "if" statement
199 	 * will go away on 64bit archs.
200 	 */
201 	if (0xfffffffe > LONG_MAX / unit && timeout > LONG_MAX / unit)
202 		return LONG_MAX / unit;
203 
204 	return timeout;
205 }
206 
207 static inline int addrconf_finite_timeout(unsigned long timeout)
208 {
209 	return ~timeout;
210 }
211 
212 /*
213  *	IPv6 Address Label subsystem (addrlabel.c)
214  */
215 int ipv6_addr_label_init(void);
216 void ipv6_addr_label_cleanup(void);
217 int ipv6_addr_label_rtnl_register(void);
218 u32 ipv6_addr_label(struct net *net, const struct in6_addr *addr,
219 		    int type, int ifindex);
220 
221 /*
222  *	multicast prototypes (mcast.c)
223  */
224 static inline bool ipv6_mc_may_pull(struct sk_buff *skb,
225 				    unsigned int len)
226 {
227 	if (skb_transport_offset(skb) + ipv6_transport_len(skb) < len)
228 		return false;
229 
230 	return pskb_may_pull(skb, len);
231 }
232 
233 int ipv6_sock_mc_join(struct sock *sk, int ifindex,
234 		      const struct in6_addr *addr);
235 int ipv6_sock_mc_drop(struct sock *sk, int ifindex,
236 		      const struct in6_addr *addr);
237 void __ipv6_sock_mc_close(struct sock *sk);
238 void ipv6_sock_mc_close(struct sock *sk);
239 bool inet6_mc_check(const struct sock *sk, const struct in6_addr *mc_addr,
240 		    const struct in6_addr *src_addr);
241 
242 int ipv6_dev_mc_inc(struct net_device *dev, const struct in6_addr *addr);
243 int __ipv6_dev_mc_dec(struct inet6_dev *idev, const struct in6_addr *addr);
244 int ipv6_dev_mc_dec(struct net_device *dev, const struct in6_addr *addr);
245 void ipv6_mc_up(struct inet6_dev *idev);
246 void ipv6_mc_down(struct inet6_dev *idev);
247 void ipv6_mc_unmap(struct inet6_dev *idev);
248 void ipv6_mc_remap(struct inet6_dev *idev);
249 void ipv6_mc_init_dev(struct inet6_dev *idev);
250 void ipv6_mc_destroy_dev(struct inet6_dev *idev);
251 int ipv6_mc_check_mld(struct sk_buff *skb);
252 void addrconf_dad_failure(struct sk_buff *skb, struct inet6_ifaddr *ifp);
253 
254 bool ipv6_chk_mcast_addr(struct net_device *dev, const struct in6_addr *group,
255 			 const struct in6_addr *src_addr);
256 
257 void ipv6_mc_dad_complete(struct inet6_dev *idev);
258 
259 /*
260  * identify MLD packets for MLD filter exceptions
261  */
262 static inline bool ipv6_is_mld(struct sk_buff *skb, int nexthdr, int offset)
263 {
264 	struct icmp6hdr *hdr;
265 
266 	if (nexthdr != IPPROTO_ICMPV6 ||
267 	    !pskb_network_may_pull(skb, offset + sizeof(struct icmp6hdr)))
268 		return false;
269 
270 	hdr = (struct icmp6hdr *)(skb_network_header(skb) + offset);
271 
272 	switch (hdr->icmp6_type) {
273 	case ICMPV6_MGM_QUERY:
274 	case ICMPV6_MGM_REPORT:
275 	case ICMPV6_MGM_REDUCTION:
276 	case ICMPV6_MLD2_REPORT:
277 		return true;
278 	default:
279 		break;
280 	}
281 	return false;
282 }
283 
284 void addrconf_prefix_rcv(struct net_device *dev,
285 			 u8 *opt, int len, bool sllao);
286 
287 /*
288  *	anycast prototypes (anycast.c)
289  */
290 int ipv6_sock_ac_join(struct sock *sk, int ifindex,
291 		      const struct in6_addr *addr);
292 int ipv6_sock_ac_drop(struct sock *sk, int ifindex,
293 		      const struct in6_addr *addr);
294 void __ipv6_sock_ac_close(struct sock *sk);
295 void ipv6_sock_ac_close(struct sock *sk);
296 
297 int __ipv6_dev_ac_inc(struct inet6_dev *idev, const struct in6_addr *addr);
298 int __ipv6_dev_ac_dec(struct inet6_dev *idev, const struct in6_addr *addr);
299 void ipv6_ac_destroy_dev(struct inet6_dev *idev);
300 bool ipv6_chk_acast_addr(struct net *net, struct net_device *dev,
301 			 const struct in6_addr *addr);
302 bool ipv6_chk_acast_addr_src(struct net *net, struct net_device *dev,
303 			     const struct in6_addr *addr);
304 int ipv6_anycast_init(void);
305 void ipv6_anycast_cleanup(void);
306 
307 /* Device notifier */
308 int register_inet6addr_notifier(struct notifier_block *nb);
309 int unregister_inet6addr_notifier(struct notifier_block *nb);
310 int inet6addr_notifier_call_chain(unsigned long val, void *v);
311 
312 int register_inet6addr_validator_notifier(struct notifier_block *nb);
313 int unregister_inet6addr_validator_notifier(struct notifier_block *nb);
314 int inet6addr_validator_notifier_call_chain(unsigned long val, void *v);
315 
316 void inet6_netconf_notify_devconf(struct net *net, int event, int type,
317 				  int ifindex, struct ipv6_devconf *devconf);
318 
319 /**
320  * __in6_dev_get - get inet6_dev pointer from netdevice
321  * @dev: network device
322  *
323  * Caller must hold rcu_read_lock or RTNL, because this function
324  * does not take a reference on the inet6_dev.
325  */
326 static inline struct inet6_dev *__in6_dev_get(const struct net_device *dev)
327 {
328 	return rcu_dereference_rtnl(dev->ip6_ptr);
329 }
330 
331 /**
332  * __in6_dev_stats_get - get inet6_dev pointer for stats
333  * @dev: network device
334  * @skb: skb for original incoming interface if neeeded
335  *
336  * Caller must hold rcu_read_lock or RTNL, because this function
337  * does not take a reference on the inet6_dev.
338  */
339 static inline struct inet6_dev *__in6_dev_stats_get(const struct net_device *dev,
340 						    const struct sk_buff *skb)
341 {
342 	if (netif_is_l3_master(dev))
343 		dev = dev_get_by_index_rcu(dev_net(dev), inet6_iif(skb));
344 	return __in6_dev_get(dev);
345 }
346 
347 /**
348  * __in6_dev_get_safely - get inet6_dev pointer from netdevice
349  * @dev: network device
350  *
351  * This is a safer version of __in6_dev_get
352  */
353 static inline struct inet6_dev *__in6_dev_get_safely(const struct net_device *dev)
354 {
355 	if (likely(dev))
356 		return rcu_dereference_rtnl(dev->ip6_ptr);
357 	else
358 		return NULL;
359 }
360 
361 /**
362  * in6_dev_get - get inet6_dev pointer from netdevice
363  * @dev: network device
364  *
365  * This version can be used in any context, and takes a reference
366  * on the inet6_dev. Callers must use in6_dev_put() later to
367  * release this reference.
368  */
369 static inline struct inet6_dev *in6_dev_get(const struct net_device *dev)
370 {
371 	struct inet6_dev *idev;
372 
373 	rcu_read_lock();
374 	idev = rcu_dereference(dev->ip6_ptr);
375 	if (idev)
376 		refcount_inc(&idev->refcnt);
377 	rcu_read_unlock();
378 	return idev;
379 }
380 
381 static inline struct neigh_parms *__in6_dev_nd_parms_get_rcu(const struct net_device *dev)
382 {
383 	struct inet6_dev *idev = __in6_dev_get(dev);
384 
385 	return idev ? idev->nd_parms : NULL;
386 }
387 
388 void in6_dev_finish_destroy(struct inet6_dev *idev);
389 
390 static inline void in6_dev_put(struct inet6_dev *idev)
391 {
392 	if (refcount_dec_and_test(&idev->refcnt))
393 		in6_dev_finish_destroy(idev);
394 }
395 
396 static inline void in6_dev_put_clear(struct inet6_dev **pidev)
397 {
398 	struct inet6_dev *idev = *pidev;
399 
400 	if (idev) {
401 		in6_dev_put(idev);
402 		*pidev = NULL;
403 	}
404 }
405 
406 static inline void __in6_dev_put(struct inet6_dev *idev)
407 {
408 	refcount_dec(&idev->refcnt);
409 }
410 
411 static inline void in6_dev_hold(struct inet6_dev *idev)
412 {
413 	refcount_inc(&idev->refcnt);
414 }
415 
416 /* called with rcu_read_lock held */
417 static inline bool ip6_ignore_linkdown(const struct net_device *dev)
418 {
419 	const struct inet6_dev *idev = __in6_dev_get(dev);
420 
421 	if (unlikely(!idev))
422 		return true;
423 
424 	return !!READ_ONCE(idev->cnf.ignore_routes_with_linkdown);
425 }
426 
427 void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp);
428 
429 static inline void in6_ifa_put(struct inet6_ifaddr *ifp)
430 {
431 	if (refcount_dec_and_test(&ifp->refcnt))
432 		inet6_ifa_finish_destroy(ifp);
433 }
434 
435 static inline void __in6_ifa_put(struct inet6_ifaddr *ifp)
436 {
437 	refcount_dec(&ifp->refcnt);
438 }
439 
440 static inline void in6_ifa_hold(struct inet6_ifaddr *ifp)
441 {
442 	refcount_inc(&ifp->refcnt);
443 }
444 
445 static inline bool in6_ifa_hold_safe(struct inet6_ifaddr *ifp)
446 {
447 	return refcount_inc_not_zero(&ifp->refcnt);
448 }
449 
450 /*
451  *	compute link-local solicited-node multicast address
452  */
453 
454 static inline void addrconf_addr_solict_mult(const struct in6_addr *addr,
455 					     struct in6_addr *solicited)
456 {
457 	ipv6_addr_set(solicited,
458 		      htonl(0xFF020000), 0,
459 		      htonl(0x1),
460 		      htonl(0xFF000000) | addr->s6_addr32[3]);
461 }
462 
463 static inline bool ipv6_addr_is_ll_all_nodes(const struct in6_addr *addr)
464 {
465 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
466 	__be64 *p = (__force __be64 *)addr;
467 	return ((p[0] ^ cpu_to_be64(0xff02000000000000UL)) | (p[1] ^ cpu_to_be64(1))) == 0UL;
468 #else
469 	return ((addr->s6_addr32[0] ^ htonl(0xff020000)) |
470 		addr->s6_addr32[1] | addr->s6_addr32[2] |
471 		(addr->s6_addr32[3] ^ htonl(0x00000001))) == 0;
472 #endif
473 }
474 
475 static inline bool ipv6_addr_is_ll_all_routers(const struct in6_addr *addr)
476 {
477 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
478 	__be64 *p = (__force __be64 *)addr;
479 	return ((p[0] ^ cpu_to_be64(0xff02000000000000UL)) | (p[1] ^ cpu_to_be64(2))) == 0UL;
480 #else
481 	return ((addr->s6_addr32[0] ^ htonl(0xff020000)) |
482 		addr->s6_addr32[1] | addr->s6_addr32[2] |
483 		(addr->s6_addr32[3] ^ htonl(0x00000002))) == 0;
484 #endif
485 }
486 
487 static inline bool ipv6_addr_is_isatap(const struct in6_addr *addr)
488 {
489 	return (addr->s6_addr32[2] | htonl(0x02000000)) == htonl(0x02005EFE);
490 }
491 
492 static inline bool ipv6_addr_is_solict_mult(const struct in6_addr *addr)
493 {
494 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
495 	__be64 *p = (__force __be64 *)addr;
496 	return ((p[0] ^ cpu_to_be64(0xff02000000000000UL)) |
497 		((p[1] ^ cpu_to_be64(0x00000001ff000000UL)) &
498 		 cpu_to_be64(0xffffffffff000000UL))) == 0UL;
499 #else
500 	return ((addr->s6_addr32[0] ^ htonl(0xff020000)) |
501 		addr->s6_addr32[1] |
502 		(addr->s6_addr32[2] ^ htonl(0x00000001)) |
503 		(addr->s6_addr[12] ^ 0xff)) == 0;
504 #endif
505 }
506 
507 static inline bool ipv6_addr_is_all_snoopers(const struct in6_addr *addr)
508 {
509 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
510 	__be64 *p = (__force __be64 *)addr;
511 
512 	return ((p[0] ^ cpu_to_be64(0xff02000000000000UL)) |
513 		(p[1] ^ cpu_to_be64(0x6a))) == 0UL;
514 #else
515 	return ((addr->s6_addr32[0] ^ htonl(0xff020000)) |
516 		addr->s6_addr32[1] | addr->s6_addr32[2] |
517 		(addr->s6_addr32[3] ^ htonl(0x0000006a))) == 0;
518 #endif
519 }
520 
521 #ifdef CONFIG_PROC_FS
522 int if6_proc_init(void);
523 void if6_proc_exit(void);
524 #endif
525 
526 #endif
527