xref: /linux/include/net/addrconf.h (revision 856e7c4b619af622d56b3b454f7bec32a170ac99)
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 #if defined(__BIG_ENDIAN_BITFIELD)
35 	__u8			onlink : 1,
36 			 	autoconf : 1,
37 				reserved : 6;
38 #elif defined(__LITTLE_ENDIAN_BITFIELD)
39 	__u8			reserved : 6,
40 				autoconf : 1,
41 				onlink : 1;
42 #else
43 #error "Please fix <asm/byteorder.h>"
44 #endif
45 	__be32			valid;
46 	__be32			prefered;
47 	__be32			reserved2;
48 
49 	struct in6_addr		prefix;
50 };
51 
52 #include <linux/netdevice.h>
53 #include <net/if_inet6.h>
54 #include <net/ipv6.h>
55 
56 struct in6_validator_info {
57 	struct in6_addr		i6vi_addr;
58 	struct inet6_dev	*i6vi_dev;
59 	struct netlink_ext_ack	*extack;
60 };
61 
62 struct ifa6_config {
63 	const struct in6_addr	*pfx;
64 	unsigned int		plen;
65 
66 	const struct in6_addr	*peer_pfx;
67 
68 	u32			rt_priority;
69 	u32			ifa_flags;
70 	u32			preferred_lft;
71 	u32			valid_lft;
72 	u16			scope;
73 };
74 
75 int addrconf_init(void);
76 void addrconf_cleanup(void);
77 
78 int addrconf_add_ifaddr(struct net *net, void __user *arg);
79 int addrconf_del_ifaddr(struct net *net, void __user *arg);
80 int addrconf_set_dstaddr(struct net *net, void __user *arg);
81 
82 int ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
83 		  const struct net_device *dev, int strict);
84 int ipv6_chk_addr_and_flags(struct net *net, const struct in6_addr *addr,
85 			    const struct net_device *dev, bool skip_dev_check,
86 			    int strict, u32 banned_flags);
87 
88 #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
89 int ipv6_chk_home_addr(struct net *net, const struct in6_addr *addr);
90 #endif
91 
92 bool ipv6_chk_custom_prefix(const struct in6_addr *addr,
93 				   const unsigned int prefix_len,
94 				   struct net_device *dev);
95 
96 int ipv6_chk_prefix(const struct in6_addr *addr, struct net_device *dev);
97 
98 struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net,
99 				     const struct in6_addr *addr,
100 				     struct net_device *dev, int strict);
101 
102 int ipv6_dev_get_saddr(struct net *net, const struct net_device *dev,
103 		       const struct in6_addr *daddr, unsigned int srcprefs,
104 		       struct in6_addr *saddr);
105 int __ipv6_get_lladdr(struct inet6_dev *idev, struct in6_addr *addr,
106 		      u32 banned_flags);
107 int ipv6_get_lladdr(struct net_device *dev, struct in6_addr *addr,
108 		    u32 banned_flags);
109 bool inet_rcv_saddr_equal(const struct sock *sk, const struct sock *sk2,
110 			  bool match_wildcard);
111 void addrconf_join_solict(struct net_device *dev, const struct in6_addr *addr);
112 void addrconf_leave_solict(struct inet6_dev *idev, const struct in6_addr *addr);
113 
114 void addrconf_add_linklocal(struct inet6_dev *idev,
115 			    const struct in6_addr *addr, u32 flags);
116 
117 int addrconf_prefix_rcv_add_addr(struct net *net, struct net_device *dev,
118 				 const struct prefix_info *pinfo,
119 				 struct inet6_dev *in6_dev,
120 				 const struct in6_addr *addr, int addr_type,
121 				 u32 addr_flags, bool sllao, bool tokenized,
122 				 __u32 valid_lft, u32 prefered_lft);
123 
124 static inline void addrconf_addr_eui48_base(u8 *eui, const char *const addr)
125 {
126 	memcpy(eui, addr, 3);
127 	eui[3] = 0xFF;
128 	eui[4] = 0xFE;
129 	memcpy(eui + 5, addr + 3, 3);
130 }
131 
132 static inline void addrconf_addr_eui48(u8 *eui, const char *const addr)
133 {
134 	addrconf_addr_eui48_base(eui, addr);
135 	eui[0] ^= 2;
136 }
137 
138 static inline int addrconf_ifid_eui48(u8 *eui, struct net_device *dev)
139 {
140 	if (dev->addr_len != ETH_ALEN)
141 		return -1;
142 
143 	/*
144 	 * The zSeries OSA network cards can be shared among various
145 	 * OS instances, but the OSA cards have only one MAC address.
146 	 * This leads to duplicate address conflicts in conjunction
147 	 * with IPv6 if more than one instance uses the same card.
148 	 *
149 	 * The driver for these cards can deliver a unique 16-bit
150 	 * identifier for each instance sharing the same card.  It is
151 	 * placed instead of 0xFFFE in the interface identifier.  The
152 	 * "u" bit of the interface identifier is not inverted in this
153 	 * case.  Hence the resulting interface identifier has local
154 	 * scope according to RFC2373.
155 	 */
156 
157 	addrconf_addr_eui48_base(eui, dev->dev_addr);
158 
159 	if (dev->dev_id) {
160 		eui[3] = (dev->dev_id >> 8) & 0xFF;
161 		eui[4] = dev->dev_id & 0xFF;
162 	} else {
163 		eui[0] ^= 2;
164 	}
165 
166 	return 0;
167 }
168 
169 static inline unsigned long addrconf_timeout_fixup(u32 timeout,
170 						   unsigned int unit)
171 {
172 	if (timeout == 0xffffffff)
173 		return ~0UL;
174 
175 	/*
176 	 * Avoid arithmetic overflow.
177 	 * Assuming unit is constant and non-zero, this "if" statement
178 	 * will go away on 64bit archs.
179 	 */
180 	if (0xfffffffe > LONG_MAX / unit && timeout > LONG_MAX / unit)
181 		return LONG_MAX / unit;
182 
183 	return timeout;
184 }
185 
186 static inline int addrconf_finite_timeout(unsigned long timeout)
187 {
188 	return ~timeout;
189 }
190 
191 /*
192  *	IPv6 Address Label subsystem (addrlabel.c)
193  */
194 int ipv6_addr_label_init(void);
195 void ipv6_addr_label_cleanup(void);
196 int ipv6_addr_label_rtnl_register(void);
197 u32 ipv6_addr_label(struct net *net, const struct in6_addr *addr,
198 		    int type, int ifindex);
199 
200 /*
201  *	multicast prototypes (mcast.c)
202  */
203 int ipv6_sock_mc_join(struct sock *sk, int ifindex,
204 		      const struct in6_addr *addr);
205 int ipv6_sock_mc_drop(struct sock *sk, int ifindex,
206 		      const struct in6_addr *addr);
207 void __ipv6_sock_mc_close(struct sock *sk);
208 void ipv6_sock_mc_close(struct sock *sk);
209 bool inet6_mc_check(struct sock *sk, const struct in6_addr *mc_addr,
210 		    const struct in6_addr *src_addr);
211 
212 int ipv6_dev_mc_inc(struct net_device *dev, const struct in6_addr *addr);
213 int __ipv6_dev_mc_dec(struct inet6_dev *idev, const struct in6_addr *addr);
214 int ipv6_dev_mc_dec(struct net_device *dev, const struct in6_addr *addr);
215 void ipv6_mc_up(struct inet6_dev *idev);
216 void ipv6_mc_down(struct inet6_dev *idev);
217 void ipv6_mc_unmap(struct inet6_dev *idev);
218 void ipv6_mc_remap(struct inet6_dev *idev);
219 void ipv6_mc_init_dev(struct inet6_dev *idev);
220 void ipv6_mc_destroy_dev(struct inet6_dev *idev);
221 int ipv6_mc_check_mld(struct sk_buff *skb, struct sk_buff **skb_trimmed);
222 void addrconf_dad_failure(struct sk_buff *skb, struct inet6_ifaddr *ifp);
223 
224 bool ipv6_chk_mcast_addr(struct net_device *dev, const struct in6_addr *group,
225 			 const struct in6_addr *src_addr);
226 
227 void ipv6_mc_dad_complete(struct inet6_dev *idev);
228 
229 /* A stub used by vxlan module. This is ugly, ideally these
230  * symbols should be built into the core kernel.
231  */
232 struct ipv6_stub {
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 	int (*ipv6_dst_lookup)(struct net *net, struct sock *sk,
238 			       struct dst_entry **dst, struct flowi6 *fl6);
239 
240 	struct fib6_table *(*fib6_get_table)(struct net *net, u32 id);
241 	struct fib6_info *(*fib6_lookup)(struct net *net, int oif,
242 					 struct flowi6 *fl6, int flags);
243 	struct fib6_info *(*fib6_table_lookup)(struct net *net,
244 					      struct fib6_table *table,
245 					      int oif, struct flowi6 *fl6,
246 					      int flags);
247 	struct fib6_info *(*fib6_multipath_select)(const struct net *net,
248 						   struct fib6_info *f6i,
249 						   struct flowi6 *fl6, int oif,
250 						   const struct sk_buff *skb,
251 						   int strict);
252 	u32 (*ip6_mtu_from_fib6)(struct fib6_info *f6i, struct in6_addr *daddr,
253 				 struct in6_addr *saddr);
254 
255 	void (*udpv6_encap_enable)(void);
256 	void (*ndisc_send_na)(struct net_device *dev, const struct in6_addr *daddr,
257 			      const struct in6_addr *solicited_addr,
258 			      bool router, bool solicited, bool override, bool inc_opt);
259 	struct neigh_table *nd_tbl;
260 };
261 extern const struct ipv6_stub *ipv6_stub __read_mostly;
262 
263 /* A stub used by bpf helpers. Similarly ugly as ipv6_stub */
264 struct ipv6_bpf_stub {
265 	int (*inet6_bind)(struct sock *sk, struct sockaddr *uaddr, int addr_len,
266 			  bool force_bind_address_no_port, bool with_lock);
267 };
268 extern const struct ipv6_bpf_stub *ipv6_bpf_stub __read_mostly;
269 
270 /*
271  * identify MLD packets for MLD filter exceptions
272  */
273 static inline bool ipv6_is_mld(struct sk_buff *skb, int nexthdr, int offset)
274 {
275 	struct icmp6hdr *hdr;
276 
277 	if (nexthdr != IPPROTO_ICMPV6 ||
278 	    !pskb_network_may_pull(skb, offset + sizeof(struct icmp6hdr)))
279 		return false;
280 
281 	hdr = (struct icmp6hdr *)(skb_network_header(skb) + offset);
282 
283 	switch (hdr->icmp6_type) {
284 	case ICMPV6_MGM_QUERY:
285 	case ICMPV6_MGM_REPORT:
286 	case ICMPV6_MGM_REDUCTION:
287 	case ICMPV6_MLD2_REPORT:
288 		return true;
289 	default:
290 		break;
291 	}
292 	return false;
293 }
294 
295 void addrconf_prefix_rcv(struct net_device *dev,
296 			 u8 *opt, int len, bool sllao);
297 
298 /*
299  *	anycast prototypes (anycast.c)
300  */
301 int ipv6_sock_ac_join(struct sock *sk, int ifindex,
302 		      const struct in6_addr *addr);
303 int ipv6_sock_ac_drop(struct sock *sk, int ifindex,
304 		      const struct in6_addr *addr);
305 void ipv6_sock_ac_close(struct sock *sk);
306 
307 int __ipv6_dev_ac_inc(struct inet6_dev *idev, const struct in6_addr *addr);
308 int __ipv6_dev_ac_dec(struct inet6_dev *idev, const struct in6_addr *addr);
309 void ipv6_ac_destroy_dev(struct inet6_dev *idev);
310 bool ipv6_chk_acast_addr(struct net *net, struct net_device *dev,
311 			 const struct in6_addr *addr);
312 bool ipv6_chk_acast_addr_src(struct net *net, struct net_device *dev,
313 			     const struct in6_addr *addr);
314 
315 /* Device notifier */
316 int register_inet6addr_notifier(struct notifier_block *nb);
317 int unregister_inet6addr_notifier(struct notifier_block *nb);
318 int inet6addr_notifier_call_chain(unsigned long val, void *v);
319 
320 int register_inet6addr_validator_notifier(struct notifier_block *nb);
321 int unregister_inet6addr_validator_notifier(struct notifier_block *nb);
322 int inet6addr_validator_notifier_call_chain(unsigned long val, void *v);
323 
324 void inet6_netconf_notify_devconf(struct net *net, int event, int type,
325 				  int ifindex, struct ipv6_devconf *devconf);
326 
327 /**
328  * __in6_dev_get - get inet6_dev pointer from netdevice
329  * @dev: network device
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_get(const struct net_device *dev)
335 {
336 	return rcu_dereference_rtnl(dev->ip6_ptr);
337 }
338 
339 /**
340  * __in6_dev_get_safely - get inet6_dev pointer from netdevice
341  * @dev: network device
342  *
343  * This is a safer version of __in6_dev_get
344  */
345 static inline struct inet6_dev *__in6_dev_get_safely(const struct net_device *dev)
346 {
347 	if (likely(dev))
348 		return rcu_dereference_rtnl(dev->ip6_ptr);
349 	else
350 		return NULL;
351 }
352 
353 /**
354  * in6_dev_get - get inet6_dev pointer from netdevice
355  * @dev: network device
356  *
357  * This version can be used in any context, and takes a reference
358  * on the inet6_dev. Callers must use in6_dev_put() later to
359  * release this reference.
360  */
361 static inline struct inet6_dev *in6_dev_get(const struct net_device *dev)
362 {
363 	struct inet6_dev *idev;
364 
365 	rcu_read_lock();
366 	idev = rcu_dereference(dev->ip6_ptr);
367 	if (idev)
368 		refcount_inc(&idev->refcnt);
369 	rcu_read_unlock();
370 	return idev;
371 }
372 
373 static inline struct neigh_parms *__in6_dev_nd_parms_get_rcu(const struct net_device *dev)
374 {
375 	struct inet6_dev *idev = __in6_dev_get(dev);
376 
377 	return idev ? idev->nd_parms : NULL;
378 }
379 
380 void in6_dev_finish_destroy(struct inet6_dev *idev);
381 
382 static inline void in6_dev_put(struct inet6_dev *idev)
383 {
384 	if (refcount_dec_and_test(&idev->refcnt))
385 		in6_dev_finish_destroy(idev);
386 }
387 
388 static inline void in6_dev_put_clear(struct inet6_dev **pidev)
389 {
390 	struct inet6_dev *idev = *pidev;
391 
392 	if (idev) {
393 		in6_dev_put(idev);
394 		*pidev = NULL;
395 	}
396 }
397 
398 static inline void __in6_dev_put(struct inet6_dev *idev)
399 {
400 	refcount_dec(&idev->refcnt);
401 }
402 
403 static inline void in6_dev_hold(struct inet6_dev *idev)
404 {
405 	refcount_inc(&idev->refcnt);
406 }
407 
408 void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp);
409 
410 static inline void in6_ifa_put(struct inet6_ifaddr *ifp)
411 {
412 	if (refcount_dec_and_test(&ifp->refcnt))
413 		inet6_ifa_finish_destroy(ifp);
414 }
415 
416 static inline void __in6_ifa_put(struct inet6_ifaddr *ifp)
417 {
418 	refcount_dec(&ifp->refcnt);
419 }
420 
421 static inline void in6_ifa_hold(struct inet6_ifaddr *ifp)
422 {
423 	refcount_inc(&ifp->refcnt);
424 }
425 
426 
427 /*
428  *	compute link-local solicited-node multicast address
429  */
430 
431 static inline void addrconf_addr_solict_mult(const struct in6_addr *addr,
432 					     struct in6_addr *solicited)
433 {
434 	ipv6_addr_set(solicited,
435 		      htonl(0xFF020000), 0,
436 		      htonl(0x1),
437 		      htonl(0xFF000000) | addr->s6_addr32[3]);
438 }
439 
440 static inline bool ipv6_addr_is_ll_all_nodes(const struct in6_addr *addr)
441 {
442 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
443 	__be64 *p = (__be64 *)addr;
444 	return ((p[0] ^ cpu_to_be64(0xff02000000000000UL)) | (p[1] ^ cpu_to_be64(1))) == 0UL;
445 #else
446 	return ((addr->s6_addr32[0] ^ htonl(0xff020000)) |
447 		addr->s6_addr32[1] | addr->s6_addr32[2] |
448 		(addr->s6_addr32[3] ^ htonl(0x00000001))) == 0;
449 #endif
450 }
451 
452 static inline bool ipv6_addr_is_ll_all_routers(const struct in6_addr *addr)
453 {
454 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
455 	__be64 *p = (__be64 *)addr;
456 	return ((p[0] ^ cpu_to_be64(0xff02000000000000UL)) | (p[1] ^ cpu_to_be64(2))) == 0UL;
457 #else
458 	return ((addr->s6_addr32[0] ^ htonl(0xff020000)) |
459 		addr->s6_addr32[1] | addr->s6_addr32[2] |
460 		(addr->s6_addr32[3] ^ htonl(0x00000002))) == 0;
461 #endif
462 }
463 
464 static inline bool ipv6_addr_is_isatap(const struct in6_addr *addr)
465 {
466 	return (addr->s6_addr32[2] | htonl(0x02000000)) == htonl(0x02005EFE);
467 }
468 
469 static inline bool ipv6_addr_is_solict_mult(const struct in6_addr *addr)
470 {
471 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
472 	__be64 *p = (__be64 *)addr;
473 	return ((p[0] ^ cpu_to_be64(0xff02000000000000UL)) |
474 		((p[1] ^ cpu_to_be64(0x00000001ff000000UL)) &
475 		 cpu_to_be64(0xffffffffff000000UL))) == 0UL;
476 #else
477 	return ((addr->s6_addr32[0] ^ htonl(0xff020000)) |
478 		addr->s6_addr32[1] |
479 		(addr->s6_addr32[2] ^ htonl(0x00000001)) |
480 		(addr->s6_addr[12] ^ 0xff)) == 0;
481 #endif
482 }
483 
484 #ifdef CONFIG_PROC_FS
485 int if6_proc_init(void);
486 void if6_proc_exit(void);
487 #endif
488 
489 #endif
490