xref: /linux/include/net/addrconf.h (revision aece2094e34e602f37403dda028f464bb41da50c)
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)
12 #define TEMP_PREFERRED_LIFETIME		(86400)
13 #define REGEN_MAX_RETRY			(3)
14 #define MAX_DESYNC_FACTOR		(600)
15 
16 #define ADDR_CHECK_FREQUENCY		(120*HZ)
17 
18 #define IPV6_MAX_ADDRESSES		16
19 
20 #define ADDRCONF_TIMER_FUZZ_MINUS	(HZ > 50 ? HZ / 50 : 1)
21 #define ADDRCONF_TIMER_FUZZ		(HZ / 4)
22 #define ADDRCONF_TIMER_FUZZ_MAX		(HZ)
23 
24 #define ADDRCONF_NOTIFY_PRIORITY	0
25 
26 #include <linux/in.h>
27 #include <linux/in6.h>
28 
29 struct prefix_info {
30 	__u8			type;
31 	__u8			length;
32 	__u8			prefix_len;
33 
34 	union __packed {
35 		__u8		flags;
36 		struct __packed {
37 #if defined(__BIG_ENDIAN_BITFIELD)
38 			__u8	onlink : 1,
39 			 	autoconf : 1,
40 				reserved : 6;
41 #elif defined(__LITTLE_ENDIAN_BITFIELD)
42 			__u8	reserved : 6,
43 				autoconf : 1,
44 				onlink : 1;
45 #else
46 #error "Please fix <asm/byteorder.h>"
47 #endif
48 		};
49 	};
50 	__be32			valid;
51 	__be32			prefered;
52 	__be32			reserved2;
53 
54 	struct in6_addr		prefix;
55 };
56 
57 /* rfc4861 4.6.2: IPv6 PIO is 32 bytes in size */
58 static_assert(sizeof(struct prefix_info) == 32);
59 
60 #include <linux/ipv6.h>
61 #include <linux/netdevice.h>
62 #include <net/if_inet6.h>
63 #include <net/ipv6.h>
64 
65 struct in6_validator_info {
66 	struct in6_addr		i6vi_addr;
67 	struct inet6_dev	*i6vi_dev;
68 	struct netlink_ext_ack	*extack;
69 };
70 
71 struct ifa6_config {
72 	const struct in6_addr	*pfx;
73 	unsigned int		plen;
74 
75 	u8			ifa_proto;
76 
77 	const struct in6_addr	*peer_pfx;
78 
79 	u32			rt_priority;
80 	u32			ifa_flags;
81 	u32			preferred_lft;
82 	u32			valid_lft;
83 	u16			scope;
84 };
85 
86 int addrconf_init(void);
87 void addrconf_cleanup(void);
88 
89 int addrconf_add_ifaddr(struct net *net, void __user *arg);
90 int addrconf_del_ifaddr(struct net *net, void __user *arg);
91 int addrconf_set_dstaddr(struct net *net, void __user *arg);
92 
93 int ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
94 		  const struct net_device *dev, int strict);
95 int ipv6_chk_addr_and_flags(struct net *net, const struct in6_addr *addr,
96 			    const struct net_device *dev, bool skip_dev_check,
97 			    int strict, u32 banned_flags);
98 
99 #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
100 int ipv6_chk_home_addr(struct net *net, const struct in6_addr *addr);
101 #endif
102 
103 int ipv6_chk_rpl_srh_loop(struct net *net, const struct in6_addr *segs,
104 			  unsigned char nsegs);
105 
106 bool ipv6_chk_custom_prefix(const struct in6_addr *addr,
107 				   const unsigned int prefix_len,
108 				   struct net_device *dev);
109 
110 int ipv6_chk_prefix(const struct in6_addr *addr, struct net_device *dev);
111 
112 struct net_device *ipv6_dev_find(struct net *net, const struct in6_addr *addr,
113 				 struct net_device *dev);
114 
115 struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net,
116 				     const struct in6_addr *addr,
117 				     struct net_device *dev, int strict);
118 
119 int ipv6_dev_get_saddr(struct net *net, const struct net_device *dev,
120 		       const struct in6_addr *daddr, unsigned int srcprefs,
121 		       struct in6_addr *saddr);
122 int ipv6_get_lladdr(struct net_device *dev, struct in6_addr *addr,
123 		    u32 banned_flags);
124 bool inet_rcv_saddr_equal(const struct sock *sk, const struct sock *sk2,
125 			  bool match_wildcard);
126 bool inet_rcv_saddr_any(const struct sock *sk);
127 void addrconf_join_solict(struct net_device *dev, const struct in6_addr *addr);
128 void addrconf_leave_solict(struct inet6_dev *idev, const struct in6_addr *addr);
129 
130 void addrconf_add_linklocal(struct inet6_dev *idev,
131 			    const struct in6_addr *addr, u32 flags);
132 
133 int addrconf_prefix_rcv_add_addr(struct net *net, struct net_device *dev,
134 				 const struct prefix_info *pinfo,
135 				 struct inet6_dev *in6_dev,
136 				 const struct in6_addr *addr, int addr_type,
137 				 u32 addr_flags, bool sllao, bool tokenized,
138 				 __u32 valid_lft, u32 prefered_lft);
139 
140 static inline void addrconf_addr_eui48_base(u8 *eui, const char *const addr)
141 {
142 	memcpy(eui, addr, 3);
143 	eui[3] = 0xFF;
144 	eui[4] = 0xFE;
145 	memcpy(eui + 5, addr + 3, 3);
146 }
147 
148 static inline void addrconf_addr_eui48(u8 *eui, const char *const addr)
149 {
150 	addrconf_addr_eui48_base(eui, addr);
151 	eui[0] ^= 2;
152 }
153 
154 static inline int addrconf_ifid_eui48(u8 *eui, struct net_device *dev)
155 {
156 	if (dev->addr_len != ETH_ALEN)
157 		return -1;
158 
159 	/*
160 	 * The zSeries OSA network cards can be shared among various
161 	 * OS instances, but the OSA cards have only one MAC address.
162 	 * This leads to duplicate address conflicts in conjunction
163 	 * with IPv6 if more than one instance uses the same card.
164 	 *
165 	 * The driver for these cards can deliver a unique 16-bit
166 	 * identifier for each instance sharing the same card.  It is
167 	 * placed instead of 0xFFFE in the interface identifier.  The
168 	 * "u" bit of the interface identifier is not inverted in this
169 	 * case.  Hence the resulting interface identifier has local
170 	 * scope according to RFC2373.
171 	 */
172 
173 	addrconf_addr_eui48_base(eui, dev->dev_addr);
174 
175 	if (dev->dev_id) {
176 		eui[3] = (dev->dev_id >> 8) & 0xFF;
177 		eui[4] = dev->dev_id & 0xFF;
178 	} else {
179 		eui[0] ^= 2;
180 	}
181 
182 	return 0;
183 }
184 
185 static inline unsigned long addrconf_timeout_fixup(u32 timeout,
186 						   unsigned int unit)
187 {
188 	if (timeout == 0xffffffff)
189 		return ~0UL;
190 
191 	/*
192 	 * Avoid arithmetic overflow.
193 	 * Assuming unit is constant and non-zero, this "if" statement
194 	 * will go away on 64bit archs.
195 	 */
196 	if (0xfffffffe > LONG_MAX / unit && timeout > LONG_MAX / unit)
197 		return LONG_MAX / unit;
198 
199 	return timeout;
200 }
201 
202 static inline int addrconf_finite_timeout(unsigned long timeout)
203 {
204 	return ~timeout;
205 }
206 
207 /*
208  *	IPv6 Address Label subsystem (addrlabel.c)
209  */
210 int ipv6_addr_label_init(void);
211 void ipv6_addr_label_cleanup(void);
212 int ipv6_addr_label_rtnl_register(void);
213 u32 ipv6_addr_label(struct net *net, const struct in6_addr *addr,
214 		    int type, int ifindex);
215 
216 /*
217  *	multicast prototypes (mcast.c)
218  */
219 static inline bool ipv6_mc_may_pull(struct sk_buff *skb,
220 				    unsigned int len)
221 {
222 	if (skb_transport_offset(skb) + ipv6_transport_len(skb) < len)
223 		return false;
224 
225 	return pskb_may_pull(skb, len);
226 }
227 
228 int ipv6_sock_mc_join(struct sock *sk, int ifindex,
229 		      const struct in6_addr *addr);
230 int ipv6_sock_mc_drop(struct sock *sk, int ifindex,
231 		      const struct in6_addr *addr);
232 void __ipv6_sock_mc_close(struct sock *sk);
233 void ipv6_sock_mc_close(struct sock *sk);
234 bool inet6_mc_check(const struct sock *sk, const struct in6_addr *mc_addr,
235 		    const struct in6_addr *src_addr);
236 
237 int ipv6_dev_mc_inc(struct net_device *dev, const struct in6_addr *addr);
238 int __ipv6_dev_mc_dec(struct inet6_dev *idev, const struct in6_addr *addr);
239 int ipv6_dev_mc_dec(struct net_device *dev, const struct in6_addr *addr);
240 void ipv6_mc_up(struct inet6_dev *idev);
241 void ipv6_mc_down(struct inet6_dev *idev);
242 void ipv6_mc_unmap(struct inet6_dev *idev);
243 void ipv6_mc_remap(struct inet6_dev *idev);
244 void ipv6_mc_init_dev(struct inet6_dev *idev);
245 void ipv6_mc_destroy_dev(struct inet6_dev *idev);
246 int ipv6_mc_check_mld(struct sk_buff *skb);
247 void addrconf_dad_failure(struct sk_buff *skb, struct inet6_ifaddr *ifp);
248 
249 bool ipv6_chk_mcast_addr(struct net_device *dev, const struct in6_addr *group,
250 			 const struct in6_addr *src_addr);
251 
252 void ipv6_mc_dad_complete(struct inet6_dev *idev);
253 
254 /*
255  * identify MLD packets for MLD filter exceptions
256  */
257 static inline bool ipv6_is_mld(struct sk_buff *skb, int nexthdr, int offset)
258 {
259 	struct icmp6hdr *hdr;
260 
261 	if (nexthdr != IPPROTO_ICMPV6 ||
262 	    !pskb_network_may_pull(skb, offset + sizeof(struct icmp6hdr)))
263 		return false;
264 
265 	hdr = (struct icmp6hdr *)(skb_network_header(skb) + offset);
266 
267 	switch (hdr->icmp6_type) {
268 	case ICMPV6_MGM_QUERY:
269 	case ICMPV6_MGM_REPORT:
270 	case ICMPV6_MGM_REDUCTION:
271 	case ICMPV6_MLD2_REPORT:
272 		return true;
273 	default:
274 		break;
275 	}
276 	return false;
277 }
278 
279 void addrconf_prefix_rcv(struct net_device *dev,
280 			 u8 *opt, int len, bool sllao);
281 
282 /*
283  *	anycast prototypes (anycast.c)
284  */
285 int ipv6_sock_ac_join(struct sock *sk, int ifindex,
286 		      const struct in6_addr *addr);
287 int ipv6_sock_ac_drop(struct sock *sk, int ifindex,
288 		      const struct in6_addr *addr);
289 void __ipv6_sock_ac_close(struct sock *sk);
290 void ipv6_sock_ac_close(struct sock *sk);
291 
292 int __ipv6_dev_ac_inc(struct inet6_dev *idev, const struct in6_addr *addr);
293 int __ipv6_dev_ac_dec(struct inet6_dev *idev, const struct in6_addr *addr);
294 void ipv6_ac_destroy_dev(struct inet6_dev *idev);
295 bool ipv6_chk_acast_addr(struct net *net, struct net_device *dev,
296 			 const struct in6_addr *addr);
297 bool ipv6_chk_acast_addr_src(struct net *net, struct net_device *dev,
298 			     const struct in6_addr *addr);
299 int ipv6_anycast_init(void);
300 void ipv6_anycast_cleanup(void);
301 
302 /* Device notifier */
303 int register_inet6addr_notifier(struct notifier_block *nb);
304 int unregister_inet6addr_notifier(struct notifier_block *nb);
305 int inet6addr_notifier_call_chain(unsigned long val, void *v);
306 
307 int register_inet6addr_validator_notifier(struct notifier_block *nb);
308 int unregister_inet6addr_validator_notifier(struct notifier_block *nb);
309 int inet6addr_validator_notifier_call_chain(unsigned long val, void *v);
310 
311 void inet6_netconf_notify_devconf(struct net *net, int event, int type,
312 				  int ifindex, struct ipv6_devconf *devconf);
313 
314 /**
315  * __in6_dev_get - get inet6_dev pointer from netdevice
316  * @dev: network device
317  *
318  * Caller must hold rcu_read_lock or RTNL, because this function
319  * does not take a reference on the inet6_dev.
320  */
321 static inline struct inet6_dev *__in6_dev_get(const struct net_device *dev)
322 {
323 	return rcu_dereference_rtnl(dev->ip6_ptr);
324 }
325 
326 /**
327  * __in6_dev_stats_get - get inet6_dev pointer for stats
328  * @dev: network device
329  * @skb: skb for original incoming interface if neeeded
330  *
331  * Caller must hold rcu_read_lock or RTNL, because this function
332  * does not take a reference on the inet6_dev.
333  */
334 static inline struct inet6_dev *__in6_dev_stats_get(const struct net_device *dev,
335 						    const struct sk_buff *skb)
336 {
337 	if (netif_is_l3_master(dev))
338 		dev = dev_get_by_index_rcu(dev_net(dev), inet6_iif(skb));
339 	return __in6_dev_get(dev);
340 }
341 
342 /**
343  * __in6_dev_get_safely - get inet6_dev pointer from netdevice
344  * @dev: network device
345  *
346  * This is a safer version of __in6_dev_get
347  */
348 static inline struct inet6_dev *__in6_dev_get_safely(const struct net_device *dev)
349 {
350 	if (likely(dev))
351 		return rcu_dereference_rtnl(dev->ip6_ptr);
352 	else
353 		return NULL;
354 }
355 
356 /**
357  * in6_dev_get - get inet6_dev pointer from netdevice
358  * @dev: network device
359  *
360  * This version can be used in any context, and takes a reference
361  * on the inet6_dev. Callers must use in6_dev_put() later to
362  * release this reference.
363  */
364 static inline struct inet6_dev *in6_dev_get(const struct net_device *dev)
365 {
366 	struct inet6_dev *idev;
367 
368 	rcu_read_lock();
369 	idev = rcu_dereference(dev->ip6_ptr);
370 	if (idev)
371 		refcount_inc(&idev->refcnt);
372 	rcu_read_unlock();
373 	return idev;
374 }
375 
376 static inline struct neigh_parms *__in6_dev_nd_parms_get_rcu(const struct net_device *dev)
377 {
378 	struct inet6_dev *idev = __in6_dev_get(dev);
379 
380 	return idev ? idev->nd_parms : NULL;
381 }
382 
383 void in6_dev_finish_destroy(struct inet6_dev *idev);
384 
385 static inline void in6_dev_put(struct inet6_dev *idev)
386 {
387 	if (refcount_dec_and_test(&idev->refcnt))
388 		in6_dev_finish_destroy(idev);
389 }
390 
391 static inline void in6_dev_put_clear(struct inet6_dev **pidev)
392 {
393 	struct inet6_dev *idev = *pidev;
394 
395 	if (idev) {
396 		in6_dev_put(idev);
397 		*pidev = NULL;
398 	}
399 }
400 
401 static inline void __in6_dev_put(struct inet6_dev *idev)
402 {
403 	refcount_dec(&idev->refcnt);
404 }
405 
406 static inline void in6_dev_hold(struct inet6_dev *idev)
407 {
408 	refcount_inc(&idev->refcnt);
409 }
410 
411 /* called with rcu_read_lock held */
412 static inline bool ip6_ignore_linkdown(const struct net_device *dev)
413 {
414 	const struct inet6_dev *idev = __in6_dev_get(dev);
415 
416 	if (unlikely(!idev))
417 		return true;
418 
419 	return !!idev->cnf.ignore_routes_with_linkdown;
420 }
421 
422 void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp);
423 
424 static inline void in6_ifa_put(struct inet6_ifaddr *ifp)
425 {
426 	if (refcount_dec_and_test(&ifp->refcnt))
427 		inet6_ifa_finish_destroy(ifp);
428 }
429 
430 static inline void __in6_ifa_put(struct inet6_ifaddr *ifp)
431 {
432 	refcount_dec(&ifp->refcnt);
433 }
434 
435 static inline void in6_ifa_hold(struct inet6_ifaddr *ifp)
436 {
437 	refcount_inc(&ifp->refcnt);
438 }
439 
440 
441 /*
442  *	compute link-local solicited-node multicast address
443  */
444 
445 static inline void addrconf_addr_solict_mult(const struct in6_addr *addr,
446 					     struct in6_addr *solicited)
447 {
448 	ipv6_addr_set(solicited,
449 		      htonl(0xFF020000), 0,
450 		      htonl(0x1),
451 		      htonl(0xFF000000) | addr->s6_addr32[3]);
452 }
453 
454 static inline bool ipv6_addr_is_ll_all_nodes(const struct in6_addr *addr)
455 {
456 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
457 	__be64 *p = (__force __be64 *)addr;
458 	return ((p[0] ^ cpu_to_be64(0xff02000000000000UL)) | (p[1] ^ cpu_to_be64(1))) == 0UL;
459 #else
460 	return ((addr->s6_addr32[0] ^ htonl(0xff020000)) |
461 		addr->s6_addr32[1] | addr->s6_addr32[2] |
462 		(addr->s6_addr32[3] ^ htonl(0x00000001))) == 0;
463 #endif
464 }
465 
466 static inline bool ipv6_addr_is_ll_all_routers(const struct in6_addr *addr)
467 {
468 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
469 	__be64 *p = (__force __be64 *)addr;
470 	return ((p[0] ^ cpu_to_be64(0xff02000000000000UL)) | (p[1] ^ cpu_to_be64(2))) == 0UL;
471 #else
472 	return ((addr->s6_addr32[0] ^ htonl(0xff020000)) |
473 		addr->s6_addr32[1] | addr->s6_addr32[2] |
474 		(addr->s6_addr32[3] ^ htonl(0x00000002))) == 0;
475 #endif
476 }
477 
478 static inline bool ipv6_addr_is_isatap(const struct in6_addr *addr)
479 {
480 	return (addr->s6_addr32[2] | htonl(0x02000000)) == htonl(0x02005EFE);
481 }
482 
483 static inline bool ipv6_addr_is_solict_mult(const struct in6_addr *addr)
484 {
485 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
486 	__be64 *p = (__force __be64 *)addr;
487 	return ((p[0] ^ cpu_to_be64(0xff02000000000000UL)) |
488 		((p[1] ^ cpu_to_be64(0x00000001ff000000UL)) &
489 		 cpu_to_be64(0xffffffffff000000UL))) == 0UL;
490 #else
491 	return ((addr->s6_addr32[0] ^ htonl(0xff020000)) |
492 		addr->s6_addr32[1] |
493 		(addr->s6_addr32[2] ^ htonl(0x00000001)) |
494 		(addr->s6_addr[12] ^ 0xff)) == 0;
495 #endif
496 }
497 
498 static inline bool ipv6_addr_is_all_snoopers(const struct in6_addr *addr)
499 {
500 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
501 	__be64 *p = (__force __be64 *)addr;
502 
503 	return ((p[0] ^ cpu_to_be64(0xff02000000000000UL)) |
504 		(p[1] ^ cpu_to_be64(0x6a))) == 0UL;
505 #else
506 	return ((addr->s6_addr32[0] ^ htonl(0xff020000)) |
507 		addr->s6_addr32[1] | addr->s6_addr32[2] |
508 		(addr->s6_addr32[3] ^ htonl(0x0000006a))) == 0;
509 #endif
510 }
511 
512 #ifdef CONFIG_PROC_FS
513 int if6_proc_init(void);
514 void if6_proc_exit(void);
515 #endif
516 
517 #endif
518