xref: /linux/include/net/addrconf.h (revision 5ce42b5de461c3154f61a023b191dd6b77ee66c0)
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 #define INFINITY_LIFE_TIME 0xFFFFFFFF
191 
192 static inline unsigned long addrconf_timeout_fixup(u32 timeout,
193 						   unsigned int unit)
194 {
195 	if (timeout == INFINITY_LIFE_TIME)
196 		return ~0UL;
197 
198 	/*
199 	 * Avoid arithmetic overflow.
200 	 * Assuming unit is constant and non-zero, this "if" statement
201 	 * will go away on 64bit archs.
202 	 */
203 	if (0xfffffffe > LONG_MAX / unit && timeout > LONG_MAX / unit)
204 		return LONG_MAX / unit;
205 
206 	return timeout;
207 }
208 
209 static inline int addrconf_finite_timeout(unsigned long timeout)
210 {
211 	return ~timeout;
212 }
213 
214 /*
215  *	IPv6 Address Label subsystem (addrlabel.c)
216  */
217 int ipv6_addr_label_init(void);
218 void ipv6_addr_label_cleanup(void);
219 int ipv6_addr_label_rtnl_register(void);
220 u32 ipv6_addr_label(struct net *net, const struct in6_addr *addr,
221 		    int type, int ifindex);
222 
223 /*
224  *	multicast prototypes (mcast.c)
225  */
226 static inline bool ipv6_mc_may_pull(struct sk_buff *skb,
227 				    unsigned int len)
228 {
229 	if (skb_transport_offset(skb) + ipv6_transport_len(skb) < len)
230 		return false;
231 
232 	return pskb_may_pull(skb, len);
233 }
234 
235 int ipv6_sock_mc_join(struct sock *sk, int ifindex,
236 		      const struct in6_addr *addr);
237 int ipv6_sock_mc_drop(struct sock *sk, int ifindex,
238 		      const struct in6_addr *addr);
239 void __ipv6_sock_mc_close(struct sock *sk);
240 void ipv6_sock_mc_close(struct sock *sk);
241 bool inet6_mc_check(const struct sock *sk, const struct in6_addr *mc_addr,
242 		    const struct in6_addr *src_addr);
243 
244 int ipv6_dev_mc_inc(struct net_device *dev, const struct in6_addr *addr);
245 int __ipv6_dev_mc_dec(struct inet6_dev *idev, const struct in6_addr *addr);
246 int ipv6_dev_mc_dec(struct net_device *dev, const struct in6_addr *addr);
247 void ipv6_mc_up(struct inet6_dev *idev);
248 void ipv6_mc_down(struct inet6_dev *idev);
249 void ipv6_mc_unmap(struct inet6_dev *idev);
250 void ipv6_mc_remap(struct inet6_dev *idev);
251 void ipv6_mc_init_dev(struct inet6_dev *idev);
252 void ipv6_mc_destroy_dev(struct inet6_dev *idev);
253 int ipv6_mc_check_mld(struct sk_buff *skb);
254 void addrconf_dad_failure(struct sk_buff *skb, struct inet6_ifaddr *ifp);
255 
256 bool ipv6_chk_mcast_addr(struct net_device *dev, const struct in6_addr *group,
257 			 const struct in6_addr *src_addr);
258 
259 void ipv6_mc_dad_complete(struct inet6_dev *idev);
260 
261 /*
262  * identify MLD packets for MLD filter exceptions
263  */
264 static inline bool ipv6_is_mld(struct sk_buff *skb, int nexthdr, int offset)
265 {
266 	struct icmp6hdr *hdr;
267 
268 	if (nexthdr != IPPROTO_ICMPV6 ||
269 	    !pskb_network_may_pull(skb, offset + sizeof(struct icmp6hdr)))
270 		return false;
271 
272 	hdr = (struct icmp6hdr *)(skb_network_header(skb) + offset);
273 
274 	switch (hdr->icmp6_type) {
275 	case ICMPV6_MGM_QUERY:
276 	case ICMPV6_MGM_REPORT:
277 	case ICMPV6_MGM_REDUCTION:
278 	case ICMPV6_MLD2_REPORT:
279 		return true;
280 	default:
281 		break;
282 	}
283 	return false;
284 }
285 
286 void addrconf_prefix_rcv(struct net_device *dev,
287 			 u8 *opt, int len, bool sllao);
288 
289 /*
290  *	anycast prototypes (anycast.c)
291  */
292 int ipv6_sock_ac_join(struct sock *sk, int ifindex,
293 		      const struct in6_addr *addr);
294 int ipv6_sock_ac_drop(struct sock *sk, int ifindex,
295 		      const struct in6_addr *addr);
296 void __ipv6_sock_ac_close(struct sock *sk);
297 void ipv6_sock_ac_close(struct sock *sk);
298 
299 int __ipv6_dev_ac_inc(struct inet6_dev *idev, const struct in6_addr *addr);
300 int __ipv6_dev_ac_dec(struct inet6_dev *idev, const struct in6_addr *addr);
301 void ipv6_ac_destroy_dev(struct inet6_dev *idev);
302 bool ipv6_chk_acast_addr(struct net *net, struct net_device *dev,
303 			 const struct in6_addr *addr);
304 bool ipv6_chk_acast_addr_src(struct net *net, struct net_device *dev,
305 			     const struct in6_addr *addr);
306 int ipv6_anycast_init(void);
307 void ipv6_anycast_cleanup(void);
308 
309 /* Device notifier */
310 int register_inet6addr_notifier(struct notifier_block *nb);
311 int unregister_inet6addr_notifier(struct notifier_block *nb);
312 int inet6addr_notifier_call_chain(unsigned long val, void *v);
313 
314 int register_inet6addr_validator_notifier(struct notifier_block *nb);
315 int unregister_inet6addr_validator_notifier(struct notifier_block *nb);
316 int inet6addr_validator_notifier_call_chain(unsigned long val, void *v);
317 
318 void inet6_netconf_notify_devconf(struct net *net, int event, int type,
319 				  int ifindex, struct ipv6_devconf *devconf);
320 
321 /**
322  * __in6_dev_get - get inet6_dev pointer from netdevice
323  * @dev: network device
324  *
325  * Caller must hold rcu_read_lock or RTNL, because this function
326  * does not take a reference on the inet6_dev.
327  */
328 static inline struct inet6_dev *__in6_dev_get(const struct net_device *dev)
329 {
330 	return rcu_dereference_rtnl(dev->ip6_ptr);
331 }
332 
333 /**
334  * __in6_dev_stats_get - get inet6_dev pointer for stats
335  * @dev: network device
336  * @skb: skb for original incoming interface if needed
337  *
338  * Caller must hold rcu_read_lock or RTNL, because this function
339  * does not take a reference on the inet6_dev.
340  */
341 static inline struct inet6_dev *__in6_dev_stats_get(const struct net_device *dev,
342 						    const struct sk_buff *skb)
343 {
344 	if (netif_is_l3_master(dev))
345 		dev = dev_get_by_index_rcu(dev_net(dev), inet6_iif(skb));
346 	return __in6_dev_get(dev);
347 }
348 
349 /**
350  * __in6_dev_get_safely - get inet6_dev pointer from netdevice
351  * @dev: network device
352  *
353  * This is a safer version of __in6_dev_get
354  */
355 static inline struct inet6_dev *__in6_dev_get_safely(const struct net_device *dev)
356 {
357 	if (likely(dev))
358 		return rcu_dereference_rtnl(dev->ip6_ptr);
359 	else
360 		return NULL;
361 }
362 
363 /**
364  * in6_dev_get - get inet6_dev pointer from netdevice
365  * @dev: network device
366  *
367  * This version can be used in any context, and takes a reference
368  * on the inet6_dev. Callers must use in6_dev_put() later to
369  * release this reference.
370  */
371 static inline struct inet6_dev *in6_dev_get(const struct net_device *dev)
372 {
373 	struct inet6_dev *idev;
374 
375 	rcu_read_lock();
376 	idev = rcu_dereference(dev->ip6_ptr);
377 	if (idev)
378 		refcount_inc(&idev->refcnt);
379 	rcu_read_unlock();
380 	return idev;
381 }
382 
383 static inline struct neigh_parms *__in6_dev_nd_parms_get_rcu(const struct net_device *dev)
384 {
385 	struct inet6_dev *idev = __in6_dev_get(dev);
386 
387 	return idev ? idev->nd_parms : NULL;
388 }
389 
390 void in6_dev_finish_destroy(struct inet6_dev *idev);
391 
392 static inline void in6_dev_put(struct inet6_dev *idev)
393 {
394 	if (refcount_dec_and_test(&idev->refcnt))
395 		in6_dev_finish_destroy(idev);
396 }
397 
398 static inline void in6_dev_put_clear(struct inet6_dev **pidev)
399 {
400 	struct inet6_dev *idev = *pidev;
401 
402 	if (idev) {
403 		in6_dev_put(idev);
404 		*pidev = NULL;
405 	}
406 }
407 
408 static inline void __in6_dev_put(struct inet6_dev *idev)
409 {
410 	refcount_dec(&idev->refcnt);
411 }
412 
413 static inline void in6_dev_hold(struct inet6_dev *idev)
414 {
415 	refcount_inc(&idev->refcnt);
416 }
417 
418 /* called with rcu_read_lock held */
419 static inline bool ip6_ignore_linkdown(const struct net_device *dev)
420 {
421 	const struct inet6_dev *idev = __in6_dev_get(dev);
422 
423 	if (unlikely(!idev))
424 		return true;
425 
426 	return !!READ_ONCE(idev->cnf.ignore_routes_with_linkdown);
427 }
428 
429 void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp);
430 
431 static inline void in6_ifa_put(struct inet6_ifaddr *ifp)
432 {
433 	if (refcount_dec_and_test(&ifp->refcnt))
434 		inet6_ifa_finish_destroy(ifp);
435 }
436 
437 static inline void __in6_ifa_put(struct inet6_ifaddr *ifp)
438 {
439 	refcount_dec(&ifp->refcnt);
440 }
441 
442 static inline void in6_ifa_hold(struct inet6_ifaddr *ifp)
443 {
444 	refcount_inc(&ifp->refcnt);
445 }
446 
447 static inline bool in6_ifa_hold_safe(struct inet6_ifaddr *ifp)
448 {
449 	return refcount_inc_not_zero(&ifp->refcnt);
450 }
451 
452 /*
453  *	compute link-local solicited-node multicast address
454  */
455 
456 static inline void addrconf_addr_solict_mult(const struct in6_addr *addr,
457 					     struct in6_addr *solicited)
458 {
459 	ipv6_addr_set(solicited,
460 		      htonl(0xFF020000), 0,
461 		      htonl(0x1),
462 		      htonl(0xFF000000) | addr->s6_addr32[3]);
463 }
464 
465 static inline bool ipv6_addr_is_ll_all_nodes(const struct in6_addr *addr)
466 {
467 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
468 	__be64 *p = (__force __be64 *)addr;
469 	return ((p[0] ^ cpu_to_be64(0xff02000000000000UL)) | (p[1] ^ cpu_to_be64(1))) == 0UL;
470 #else
471 	return ((addr->s6_addr32[0] ^ htonl(0xff020000)) |
472 		addr->s6_addr32[1] | addr->s6_addr32[2] |
473 		(addr->s6_addr32[3] ^ htonl(0x00000001))) == 0;
474 #endif
475 }
476 
477 static inline bool ipv6_addr_is_ll_all_routers(const struct in6_addr *addr)
478 {
479 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
480 	__be64 *p = (__force __be64 *)addr;
481 	return ((p[0] ^ cpu_to_be64(0xff02000000000000UL)) | (p[1] ^ cpu_to_be64(2))) == 0UL;
482 #else
483 	return ((addr->s6_addr32[0] ^ htonl(0xff020000)) |
484 		addr->s6_addr32[1] | addr->s6_addr32[2] |
485 		(addr->s6_addr32[3] ^ htonl(0x00000002))) == 0;
486 #endif
487 }
488 
489 static inline bool ipv6_addr_is_isatap(const struct in6_addr *addr)
490 {
491 	return (addr->s6_addr32[2] | htonl(0x02000000)) == htonl(0x02005EFE);
492 }
493 
494 static inline bool ipv6_addr_is_solict_mult(const struct in6_addr *addr)
495 {
496 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
497 	__be64 *p = (__force __be64 *)addr;
498 	return ((p[0] ^ cpu_to_be64(0xff02000000000000UL)) |
499 		((p[1] ^ cpu_to_be64(0x00000001ff000000UL)) &
500 		 cpu_to_be64(0xffffffffff000000UL))) == 0UL;
501 #else
502 	return ((addr->s6_addr32[0] ^ htonl(0xff020000)) |
503 		addr->s6_addr32[1] |
504 		(addr->s6_addr32[2] ^ htonl(0x00000001)) |
505 		(addr->s6_addr[12] ^ 0xff)) == 0;
506 #endif
507 }
508 
509 static inline bool ipv6_addr_is_all_snoopers(const struct in6_addr *addr)
510 {
511 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
512 	__be64 *p = (__force __be64 *)addr;
513 
514 	return ((p[0] ^ cpu_to_be64(0xff02000000000000UL)) |
515 		(p[1] ^ cpu_to_be64(0x6a))) == 0UL;
516 #else
517 	return ((addr->s6_addr32[0] ^ htonl(0xff020000)) |
518 		addr->s6_addr32[1] | addr->s6_addr32[2] |
519 		(addr->s6_addr32[3] ^ htonl(0x0000006a))) == 0;
520 #endif
521 }
522 
523 #ifdef CONFIG_PROC_FS
524 int if6_proc_init(void);
525 void if6_proc_exit(void);
526 #endif
527 
528 #endif
529