xref: /linux/include/net/ipv6.h (revision 61cb9ac66b30374c7fd8a8b2a3c4f8f432c72e36)
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  *	Linux INET6 implementation
4  *
5  *	Authors:
6  *	Pedro Roque		<roque@di.fc.ul.pt>
7  */
8 
9 #ifndef _NET_IPV6_H
10 #define _NET_IPV6_H
11 
12 #include <linux/ipv6.h>
13 #include <linux/hardirq.h>
14 #include <linux/jhash.h>
15 #include <linux/refcount.h>
16 #include <linux/jump_label_ratelimit.h>
17 #include <net/if_inet6.h>
18 #include <net/ndisc.h>
19 #include <net/flow.h>
20 #include <net/flow_dissector.h>
21 #include <net/snmp.h>
22 #include <net/netns/hash.h>
23 
24 #define SIN6_LEN_RFC2133	24
25 
26 #define IPV6_MAXPLEN		65535
27 
28 /*
29  *	NextHeader field of IPv6 header
30  */
31 
32 #define NEXTHDR_HOP		0	/* Hop-by-hop option header. */
33 #define NEXTHDR_IPV4		4	/* IPv4 in IPv6 */
34 #define NEXTHDR_TCP		6	/* TCP segment. */
35 #define NEXTHDR_UDP		17	/* UDP message. */
36 #define NEXTHDR_IPV6		41	/* IPv6 in IPv6 */
37 #define NEXTHDR_ROUTING		43	/* Routing header. */
38 #define NEXTHDR_FRAGMENT	44	/* Fragmentation/reassembly header. */
39 #define NEXTHDR_GRE		47	/* GRE header. */
40 #define NEXTHDR_ESP		50	/* Encapsulating security payload. */
41 #define NEXTHDR_AUTH		51	/* Authentication header. */
42 #define NEXTHDR_ICMP		58	/* ICMP for IPv6. */
43 #define NEXTHDR_NONE		59	/* No next header */
44 #define NEXTHDR_DEST		60	/* Destination options header. */
45 #define NEXTHDR_SCTP		132	/* SCTP message. */
46 #define NEXTHDR_MOBILITY	135	/* Mobility header. */
47 
48 #define NEXTHDR_MAX		255
49 
50 #define IPV6_DEFAULT_HOPLIMIT   64
51 #define IPV6_DEFAULT_MCASTHOPS	1
52 
53 /* Limits on Hop-by-Hop and Destination options.
54  *
55  * Per RFC8200 there is no limit on the maximum number or lengths of options in
56  * Hop-by-Hop or Destination options other then the packet must fit in an MTU.
57  * We allow configurable limits in order to mitigate potential denial of
58  * service attacks.
59  *
60  * There are three limits that may be set:
61  *   - Limit the number of options in a Hop-by-Hop or Destination options
62  *     extension header
63  *   - Limit the byte length of a Hop-by-Hop or Destination options extension
64  *     header
65  *   - Disallow unknown options
66  *
67  * The limits are expressed in corresponding sysctls:
68  *
69  * ipv6.sysctl.max_dst_opts_cnt
70  * ipv6.sysctl.max_hbh_opts_cnt
71  * ipv6.sysctl.max_dst_opts_len
72  * ipv6.sysctl.max_hbh_opts_len
73  *
74  * max_*_opts_cnt is the number of TLVs that are allowed for Destination
75  * options or Hop-by-Hop options. If the number is less than zero then unknown
76  * TLVs are disallowed and the number of known options that are allowed is the
77  * absolute value. Setting the value to INT_MAX indicates no limit.
78  *
79  * max_*_opts_len is the length limit in bytes of a Destination or
80  * Hop-by-Hop options extension header. Setting the value to INT_MAX
81  * indicates no length limit.
82  *
83  * If a limit is exceeded when processing an extension header the packet is
84  * silently discarded.
85  */
86 
87 /* Default limits for Hop-by-Hop and Destination options */
88 #define IP6_DEFAULT_MAX_DST_OPTS_CNT	 8
89 #define IP6_DEFAULT_MAX_HBH_OPTS_CNT	 8
90 #define IP6_DEFAULT_MAX_DST_OPTS_LEN	 INT_MAX /* No limit */
91 #define IP6_DEFAULT_MAX_HBH_OPTS_LEN	 INT_MAX /* No limit */
92 
93 /*
94  *	Addr type
95  *
96  *	type	-	unicast | multicast
97  *	scope	-	local	| site	    | global
98  *	v4	-	compat
99  *	v4mapped
100  *	any
101  *	loopback
102  */
103 
104 #define IPV6_ADDR_ANY		0x0000U
105 
106 #define IPV6_ADDR_UNICAST	0x0001U
107 #define IPV6_ADDR_MULTICAST	0x0002U
108 
109 #define IPV6_ADDR_LOOPBACK	0x0010U
110 #define IPV6_ADDR_LINKLOCAL	0x0020U
111 #define IPV6_ADDR_SITELOCAL	0x0040U
112 
113 #define IPV6_ADDR_COMPATv4	0x0080U
114 
115 #define IPV6_ADDR_SCOPE_MASK	0x00f0U
116 
117 #define IPV6_ADDR_MAPPED	0x1000U
118 
119 /*
120  *	Addr scopes
121  */
122 #define IPV6_ADDR_MC_SCOPE(a)	\
123 	((a)->s6_addr[1] & 0x0f)	/* nonstandard */
124 #define __IPV6_ADDR_SCOPE_INVALID	-1
125 #define IPV6_ADDR_SCOPE_NODELOCAL	0x01
126 #define IPV6_ADDR_SCOPE_LINKLOCAL	0x02
127 #define IPV6_ADDR_SCOPE_SITELOCAL	0x05
128 #define IPV6_ADDR_SCOPE_ORGLOCAL	0x08
129 #define IPV6_ADDR_SCOPE_GLOBAL		0x0e
130 
131 /*
132  *	Addr flags
133  */
134 #define IPV6_ADDR_MC_FLAG_TRANSIENT(a)	\
135 	((a)->s6_addr[1] & 0x10)
136 #define IPV6_ADDR_MC_FLAG_PREFIX(a)	\
137 	((a)->s6_addr[1] & 0x20)
138 #define IPV6_ADDR_MC_FLAG_RENDEZVOUS(a)	\
139 	((a)->s6_addr[1] & 0x40)
140 
141 /*
142  *	fragmentation header
143  */
144 
145 struct frag_hdr {
146 	__u8	nexthdr;
147 	__u8	reserved;
148 	__be16	frag_off;
149 	__be32	identification;
150 };
151 
152 #define	IP6_MF		0x0001
153 #define	IP6_OFFSET	0xFFF8
154 
155 struct ip6_fraglist_iter {
156 	struct ipv6hdr	*tmp_hdr;
157 	struct sk_buff	*frag;
158 	int		offset;
159 	unsigned int	hlen;
160 	__be32		frag_id;
161 	u8		nexthdr;
162 };
163 
164 int ip6_fraglist_init(struct sk_buff *skb, unsigned int hlen, u8 *prevhdr,
165 		      u8 nexthdr, __be32 frag_id,
166 		      struct ip6_fraglist_iter *iter);
167 void ip6_fraglist_prepare(struct sk_buff *skb, struct ip6_fraglist_iter *iter);
168 
169 static inline struct sk_buff *ip6_fraglist_next(struct ip6_fraglist_iter *iter)
170 {
171 	struct sk_buff *skb = iter->frag;
172 
173 	iter->frag = skb->next;
174 	skb_mark_not_on_list(skb);
175 
176 	return skb;
177 }
178 
179 struct ip6_frag_state {
180 	u8		*prevhdr;
181 	unsigned int	hlen;
182 	unsigned int	mtu;
183 	unsigned int	left;
184 	int		offset;
185 	int		ptr;
186 	int		hroom;
187 	int		troom;
188 	__be32		frag_id;
189 	u8		nexthdr;
190 };
191 
192 void ip6_frag_init(struct sk_buff *skb, unsigned int hlen, unsigned int mtu,
193 		   unsigned short needed_tailroom, int hdr_room, u8 *prevhdr,
194 		   u8 nexthdr, __be32 frag_id, struct ip6_frag_state *state);
195 struct sk_buff *ip6_frag_next(struct sk_buff *skb,
196 			      struct ip6_frag_state *state);
197 
198 #define IP6_REPLY_MARK(net, mark) \
199 	((net)->ipv6.sysctl.fwmark_reflect ? (mark) : 0)
200 
201 #include <net/sock.h>
202 
203 /* sysctls */
204 extern int sysctl_mld_max_msf;
205 extern int sysctl_mld_qrv;
206 
207 #define _DEVINC(net, statname, mod, idev, field)			\
208 ({									\
209 	struct inet6_dev *_idev = (idev);				\
210 	if (likely(_idev != NULL))					\
211 		mod##SNMP_INC_STATS64((_idev)->stats.statname, (field));\
212 	mod##SNMP_INC_STATS64((net)->mib.statname##_statistics, (field));\
213 })
214 
215 /* per device counters are atomic_long_t */
216 #define _DEVINCATOMIC(net, statname, mod, idev, field)			\
217 ({									\
218 	struct inet6_dev *_idev = (idev);				\
219 	if (likely(_idev != NULL))					\
220 		SNMP_INC_STATS_ATOMIC_LONG((_idev)->stats.statname##dev, (field)); \
221 	mod##SNMP_INC_STATS((net)->mib.statname##_statistics, (field));\
222 })
223 
224 /* per device and per net counters are atomic_long_t */
225 #define _DEVINC_ATOMIC_ATOMIC(net, statname, idev, field)		\
226 ({									\
227 	struct inet6_dev *_idev = (idev);				\
228 	if (likely(_idev != NULL))					\
229 		SNMP_INC_STATS_ATOMIC_LONG((_idev)->stats.statname##dev, (field)); \
230 	SNMP_INC_STATS_ATOMIC_LONG((net)->mib.statname##_statistics, (field));\
231 })
232 
233 #define _DEVADD(net, statname, mod, idev, field, val)			\
234 ({									\
235 	struct inet6_dev *_idev = (idev);				\
236 	if (likely(_idev != NULL))					\
237 		mod##SNMP_ADD_STATS((_idev)->stats.statname, (field), (val)); \
238 	mod##SNMP_ADD_STATS((net)->mib.statname##_statistics, (field), (val));\
239 })
240 
241 #define _DEVUPD(net, statname, mod, idev, field, val)			\
242 ({									\
243 	struct inet6_dev *_idev = (idev);				\
244 	if (likely(_idev != NULL))					\
245 		mod##SNMP_UPD_PO_STATS((_idev)->stats.statname, field, (val)); \
246 	mod##SNMP_UPD_PO_STATS((net)->mib.statname##_statistics, field, (val));\
247 })
248 
249 /* MIBs */
250 
251 #define IP6_INC_STATS(net, idev,field)		\
252 		_DEVINC(net, ipv6, , idev, field)
253 #define __IP6_INC_STATS(net, idev,field)	\
254 		_DEVINC(net, ipv6, __, idev, field)
255 #define IP6_ADD_STATS(net, idev,field,val)	\
256 		_DEVADD(net, ipv6, , idev, field, val)
257 #define __IP6_ADD_STATS(net, idev,field,val)	\
258 		_DEVADD(net, ipv6, __, idev, field, val)
259 #define IP6_UPD_PO_STATS(net, idev,field,val)   \
260 		_DEVUPD(net, ipv6, , idev, field, val)
261 #define __IP6_UPD_PO_STATS(net, idev,field,val)   \
262 		_DEVUPD(net, ipv6, __, idev, field, val)
263 #define ICMP6_INC_STATS(net, idev, field)	\
264 		_DEVINCATOMIC(net, icmpv6, , idev, field)
265 #define __ICMP6_INC_STATS(net, idev, field)	\
266 		_DEVINCATOMIC(net, icmpv6, __, idev, field)
267 
268 #define ICMP6MSGOUT_INC_STATS(net, idev, field)		\
269 	_DEVINC_ATOMIC_ATOMIC(net, icmpv6msg, idev, field +256)
270 #define ICMP6MSGIN_INC_STATS(net, idev, field)	\
271 	_DEVINC_ATOMIC_ATOMIC(net, icmpv6msg, idev, field)
272 
273 struct ip6_ra_chain {
274 	struct ip6_ra_chain	*next;
275 	struct sock		*sk;
276 	int			sel;
277 	void			(*destructor)(struct sock *);
278 };
279 
280 extern struct ip6_ra_chain	*ip6_ra_chain;
281 extern rwlock_t ip6_ra_lock;
282 
283 /*
284    This structure is prepared by protocol, when parsing
285    ancillary data and passed to IPv6.
286  */
287 
288 struct ipv6_txoptions {
289 	refcount_t		refcnt;
290 	/* Length of this structure */
291 	int			tot_len;
292 
293 	/* length of extension headers   */
294 
295 	__u16			opt_flen;	/* after fragment hdr */
296 	__u16			opt_nflen;	/* before fragment hdr */
297 
298 	struct ipv6_opt_hdr	*hopopt;
299 	struct ipv6_opt_hdr	*dst0opt;
300 	struct ipv6_rt_hdr	*srcrt;	/* Routing Header */
301 	struct ipv6_opt_hdr	*dst1opt;
302 	struct rcu_head		rcu;
303 	/* Option buffer, as read by IPV6_PKTOPTIONS, starts here. */
304 };
305 
306 /* flowlabel_reflect sysctl values */
307 enum flowlabel_reflect {
308 	FLOWLABEL_REFLECT_ESTABLISHED		= 1,
309 	FLOWLABEL_REFLECT_TCP_RESET		= 2,
310 	FLOWLABEL_REFLECT_ICMPV6_ECHO_REPLIES	= 4,
311 };
312 
313 struct ip6_flowlabel {
314 	struct ip6_flowlabel __rcu *next;
315 	__be32			label;
316 	atomic_t		users;
317 	struct in6_addr		dst;
318 	struct ipv6_txoptions	*opt;
319 	unsigned long		linger;
320 	struct rcu_head		rcu;
321 	u8			share;
322 	union {
323 		struct pid *pid;
324 		kuid_t uid;
325 	} owner;
326 	unsigned long		lastuse;
327 	unsigned long		expires;
328 	struct net		*fl_net;
329 };
330 
331 #define IPV6_FLOWINFO_MASK		cpu_to_be32(0x0FFFFFFF)
332 #define IPV6_FLOWLABEL_MASK		cpu_to_be32(0x000FFFFF)
333 #define IPV6_FLOWLABEL_STATELESS_FLAG	cpu_to_be32(0x00080000)
334 
335 #define IPV6_TCLASS_MASK (IPV6_FLOWINFO_MASK & ~IPV6_FLOWLABEL_MASK)
336 #define IPV6_TCLASS_SHIFT	20
337 
338 struct ipv6_fl_socklist {
339 	struct ipv6_fl_socklist	__rcu	*next;
340 	struct ip6_flowlabel		*fl;
341 	struct rcu_head			rcu;
342 };
343 
344 struct ipcm6_cookie {
345 	struct sockcm_cookie sockc;
346 	__s16 hlimit;
347 	__s16 tclass;
348 	__s8  dontfrag;
349 	struct ipv6_txoptions *opt;
350 	__u16 gso_size;
351 };
352 
353 static inline void ipcm6_init(struct ipcm6_cookie *ipc6)
354 {
355 	*ipc6 = (struct ipcm6_cookie) {
356 		.hlimit = -1,
357 		.tclass = -1,
358 		.dontfrag = -1,
359 	};
360 }
361 
362 static inline void ipcm6_init_sk(struct ipcm6_cookie *ipc6,
363 				 const struct ipv6_pinfo *np)
364 {
365 	*ipc6 = (struct ipcm6_cookie) {
366 		.hlimit = -1,
367 		.tclass = np->tclass,
368 		.dontfrag = np->dontfrag,
369 	};
370 }
371 
372 static inline struct ipv6_txoptions *txopt_get(const struct ipv6_pinfo *np)
373 {
374 	struct ipv6_txoptions *opt;
375 
376 	rcu_read_lock();
377 	opt = rcu_dereference(np->opt);
378 	if (opt) {
379 		if (!refcount_inc_not_zero(&opt->refcnt))
380 			opt = NULL;
381 		else
382 			opt = rcu_pointer_handoff(opt);
383 	}
384 	rcu_read_unlock();
385 	return opt;
386 }
387 
388 static inline void txopt_put(struct ipv6_txoptions *opt)
389 {
390 	if (opt && refcount_dec_and_test(&opt->refcnt))
391 		kfree_rcu(opt, rcu);
392 }
393 
394 struct ip6_flowlabel *__fl6_sock_lookup(struct sock *sk, __be32 label);
395 
396 extern struct static_key_false_deferred ipv6_flowlabel_exclusive;
397 static inline struct ip6_flowlabel *fl6_sock_lookup(struct sock *sk,
398 						    __be32 label)
399 {
400 	if (static_branch_unlikely(&ipv6_flowlabel_exclusive.key))
401 		return __fl6_sock_lookup(sk, label) ? : ERR_PTR(-ENOENT);
402 
403 	return NULL;
404 }
405 
406 struct ipv6_txoptions *fl6_merge_options(struct ipv6_txoptions *opt_space,
407 					 struct ip6_flowlabel *fl,
408 					 struct ipv6_txoptions *fopt);
409 void fl6_free_socklist(struct sock *sk);
410 int ipv6_flowlabel_opt(struct sock *sk, sockptr_t optval, int optlen);
411 int ipv6_flowlabel_opt_get(struct sock *sk, struct in6_flowlabel_req *freq,
412 			   int flags);
413 int ip6_flowlabel_init(void);
414 void ip6_flowlabel_cleanup(void);
415 bool ip6_autoflowlabel(struct net *net, const struct ipv6_pinfo *np);
416 
417 static inline void fl6_sock_release(struct ip6_flowlabel *fl)
418 {
419 	if (fl)
420 		atomic_dec(&fl->users);
421 }
422 
423 void icmpv6_notify(struct sk_buff *skb, u8 type, u8 code, __be32 info);
424 
425 void icmpv6_push_pending_frames(struct sock *sk, struct flowi6 *fl6,
426 				struct icmp6hdr *thdr, int len);
427 
428 int ip6_ra_control(struct sock *sk, int sel);
429 
430 int ipv6_parse_hopopts(struct sk_buff *skb);
431 
432 struct ipv6_txoptions *ipv6_dup_options(struct sock *sk,
433 					struct ipv6_txoptions *opt);
434 struct ipv6_txoptions *ipv6_renew_options(struct sock *sk,
435 					  struct ipv6_txoptions *opt,
436 					  int newtype,
437 					  struct ipv6_opt_hdr *newopt);
438 struct ipv6_txoptions *ipv6_fixup_options(struct ipv6_txoptions *opt_space,
439 					  struct ipv6_txoptions *opt);
440 
441 bool ipv6_opt_accepted(const struct sock *sk, const struct sk_buff *skb,
442 		       const struct inet6_skb_parm *opt);
443 struct ipv6_txoptions *ipv6_update_options(struct sock *sk,
444 					   struct ipv6_txoptions *opt);
445 
446 static inline bool ipv6_accept_ra(struct inet6_dev *idev)
447 {
448 	/* If forwarding is enabled, RA are not accepted unless the special
449 	 * hybrid mode (accept_ra=2) is enabled.
450 	 */
451 	return idev->cnf.forwarding ? idev->cnf.accept_ra == 2 :
452 	    idev->cnf.accept_ra;
453 }
454 
455 #define IPV6_FRAG_HIGH_THRESH	(4 * 1024*1024)	/* 4194304 */
456 #define IPV6_FRAG_LOW_THRESH	(3 * 1024*1024)	/* 3145728 */
457 #define IPV6_FRAG_TIMEOUT	(60 * HZ)	/* 60 seconds */
458 
459 int __ipv6_addr_type(const struct in6_addr *addr);
460 static inline int ipv6_addr_type(const struct in6_addr *addr)
461 {
462 	return __ipv6_addr_type(addr) & 0xffff;
463 }
464 
465 static inline int ipv6_addr_scope(const struct in6_addr *addr)
466 {
467 	return __ipv6_addr_type(addr) & IPV6_ADDR_SCOPE_MASK;
468 }
469 
470 static inline int __ipv6_addr_src_scope(int type)
471 {
472 	return (type == IPV6_ADDR_ANY) ? __IPV6_ADDR_SCOPE_INVALID : (type >> 16);
473 }
474 
475 static inline int ipv6_addr_src_scope(const struct in6_addr *addr)
476 {
477 	return __ipv6_addr_src_scope(__ipv6_addr_type(addr));
478 }
479 
480 static inline bool __ipv6_addr_needs_scope_id(int type)
481 {
482 	return type & IPV6_ADDR_LINKLOCAL ||
483 	       (type & IPV6_ADDR_MULTICAST &&
484 		(type & (IPV6_ADDR_LOOPBACK|IPV6_ADDR_LINKLOCAL)));
485 }
486 
487 static inline __u32 ipv6_iface_scope_id(const struct in6_addr *addr, int iface)
488 {
489 	return __ipv6_addr_needs_scope_id(__ipv6_addr_type(addr)) ? iface : 0;
490 }
491 
492 static inline int ipv6_addr_cmp(const struct in6_addr *a1, const struct in6_addr *a2)
493 {
494 	return memcmp(a1, a2, sizeof(struct in6_addr));
495 }
496 
497 static inline bool
498 ipv6_masked_addr_cmp(const struct in6_addr *a1, const struct in6_addr *m,
499 		     const struct in6_addr *a2)
500 {
501 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
502 	const unsigned long *ul1 = (const unsigned long *)a1;
503 	const unsigned long *ulm = (const unsigned long *)m;
504 	const unsigned long *ul2 = (const unsigned long *)a2;
505 
506 	return !!(((ul1[0] ^ ul2[0]) & ulm[0]) |
507 		  ((ul1[1] ^ ul2[1]) & ulm[1]));
508 #else
509 	return !!(((a1->s6_addr32[0] ^ a2->s6_addr32[0]) & m->s6_addr32[0]) |
510 		  ((a1->s6_addr32[1] ^ a2->s6_addr32[1]) & m->s6_addr32[1]) |
511 		  ((a1->s6_addr32[2] ^ a2->s6_addr32[2]) & m->s6_addr32[2]) |
512 		  ((a1->s6_addr32[3] ^ a2->s6_addr32[3]) & m->s6_addr32[3]));
513 #endif
514 }
515 
516 static inline void ipv6_addr_prefix(struct in6_addr *pfx,
517 				    const struct in6_addr *addr,
518 				    int plen)
519 {
520 	/* caller must guarantee 0 <= plen <= 128 */
521 	int o = plen >> 3,
522 	    b = plen & 0x7;
523 
524 	memset(pfx->s6_addr, 0, sizeof(pfx->s6_addr));
525 	memcpy(pfx->s6_addr, addr, o);
526 	if (b != 0)
527 		pfx->s6_addr[o] = addr->s6_addr[o] & (0xff00 >> b);
528 }
529 
530 static inline void ipv6_addr_prefix_copy(struct in6_addr *addr,
531 					 const struct in6_addr *pfx,
532 					 int plen)
533 {
534 	/* caller must guarantee 0 <= plen <= 128 */
535 	int o = plen >> 3,
536 	    b = plen & 0x7;
537 
538 	memcpy(addr->s6_addr, pfx, o);
539 	if (b != 0) {
540 		addr->s6_addr[o] &= ~(0xff00 >> b);
541 		addr->s6_addr[o] |= (pfx->s6_addr[o] & (0xff00 >> b));
542 	}
543 }
544 
545 static inline void __ipv6_addr_set_half(__be32 *addr,
546 					__be32 wh, __be32 wl)
547 {
548 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
549 #if defined(__BIG_ENDIAN)
550 	if (__builtin_constant_p(wh) && __builtin_constant_p(wl)) {
551 		*(__force u64 *)addr = ((__force u64)(wh) << 32 | (__force u64)(wl));
552 		return;
553 	}
554 #elif defined(__LITTLE_ENDIAN)
555 	if (__builtin_constant_p(wl) && __builtin_constant_p(wh)) {
556 		*(__force u64 *)addr = ((__force u64)(wl) << 32 | (__force u64)(wh));
557 		return;
558 	}
559 #endif
560 #endif
561 	addr[0] = wh;
562 	addr[1] = wl;
563 }
564 
565 static inline void ipv6_addr_set(struct in6_addr *addr,
566 				     __be32 w1, __be32 w2,
567 				     __be32 w3, __be32 w4)
568 {
569 	__ipv6_addr_set_half(&addr->s6_addr32[0], w1, w2);
570 	__ipv6_addr_set_half(&addr->s6_addr32[2], w3, w4);
571 }
572 
573 static inline bool ipv6_addr_equal(const struct in6_addr *a1,
574 				   const struct in6_addr *a2)
575 {
576 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
577 	const unsigned long *ul1 = (const unsigned long *)a1;
578 	const unsigned long *ul2 = (const unsigned long *)a2;
579 
580 	return ((ul1[0] ^ ul2[0]) | (ul1[1] ^ ul2[1])) == 0UL;
581 #else
582 	return ((a1->s6_addr32[0] ^ a2->s6_addr32[0]) |
583 		(a1->s6_addr32[1] ^ a2->s6_addr32[1]) |
584 		(a1->s6_addr32[2] ^ a2->s6_addr32[2]) |
585 		(a1->s6_addr32[3] ^ a2->s6_addr32[3])) == 0;
586 #endif
587 }
588 
589 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
590 static inline bool __ipv6_prefix_equal64_half(const __be64 *a1,
591 					      const __be64 *a2,
592 					      unsigned int len)
593 {
594 	if (len && ((*a1 ^ *a2) & cpu_to_be64((~0UL) << (64 - len))))
595 		return false;
596 	return true;
597 }
598 
599 static inline bool ipv6_prefix_equal(const struct in6_addr *addr1,
600 				     const struct in6_addr *addr2,
601 				     unsigned int prefixlen)
602 {
603 	const __be64 *a1 = (const __be64 *)addr1;
604 	const __be64 *a2 = (const __be64 *)addr2;
605 
606 	if (prefixlen >= 64) {
607 		if (a1[0] ^ a2[0])
608 			return false;
609 		return __ipv6_prefix_equal64_half(a1 + 1, a2 + 1, prefixlen - 64);
610 	}
611 	return __ipv6_prefix_equal64_half(a1, a2, prefixlen);
612 }
613 #else
614 static inline bool ipv6_prefix_equal(const struct in6_addr *addr1,
615 				     const struct in6_addr *addr2,
616 				     unsigned int prefixlen)
617 {
618 	const __be32 *a1 = addr1->s6_addr32;
619 	const __be32 *a2 = addr2->s6_addr32;
620 	unsigned int pdw, pbi;
621 
622 	/* check complete u32 in prefix */
623 	pdw = prefixlen >> 5;
624 	if (pdw && memcmp(a1, a2, pdw << 2))
625 		return false;
626 
627 	/* check incomplete u32 in prefix */
628 	pbi = prefixlen & 0x1f;
629 	if (pbi && ((a1[pdw] ^ a2[pdw]) & htonl((0xffffffff) << (32 - pbi))))
630 		return false;
631 
632 	return true;
633 }
634 #endif
635 
636 static inline bool ipv6_addr_any(const struct in6_addr *a)
637 {
638 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
639 	const unsigned long *ul = (const unsigned long *)a;
640 
641 	return (ul[0] | ul[1]) == 0UL;
642 #else
643 	return (a->s6_addr32[0] | a->s6_addr32[1] |
644 		a->s6_addr32[2] | a->s6_addr32[3]) == 0;
645 #endif
646 }
647 
648 static inline u32 ipv6_addr_hash(const struct in6_addr *a)
649 {
650 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
651 	const unsigned long *ul = (const unsigned long *)a;
652 	unsigned long x = ul[0] ^ ul[1];
653 
654 	return (u32)(x ^ (x >> 32));
655 #else
656 	return (__force u32)(a->s6_addr32[0] ^ a->s6_addr32[1] ^
657 			     a->s6_addr32[2] ^ a->s6_addr32[3]);
658 #endif
659 }
660 
661 /* more secured version of ipv6_addr_hash() */
662 static inline u32 __ipv6_addr_jhash(const struct in6_addr *a, const u32 initval)
663 {
664 	u32 v = (__force u32)a->s6_addr32[0] ^ (__force u32)a->s6_addr32[1];
665 
666 	return jhash_3words(v,
667 			    (__force u32)a->s6_addr32[2],
668 			    (__force u32)a->s6_addr32[3],
669 			    initval);
670 }
671 
672 static inline bool ipv6_addr_loopback(const struct in6_addr *a)
673 {
674 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
675 	const __be64 *be = (const __be64 *)a;
676 
677 	return (be[0] | (be[1] ^ cpu_to_be64(1))) == 0UL;
678 #else
679 	return (a->s6_addr32[0] | a->s6_addr32[1] |
680 		a->s6_addr32[2] | (a->s6_addr32[3] ^ cpu_to_be32(1))) == 0;
681 #endif
682 }
683 
684 /*
685  * Note that we must __force cast these to unsigned long to make sparse happy,
686  * since all of the endian-annotated types are fixed size regardless of arch.
687  */
688 static inline bool ipv6_addr_v4mapped(const struct in6_addr *a)
689 {
690 	return (
691 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
692 		*(unsigned long *)a |
693 #else
694 		(__force unsigned long)(a->s6_addr32[0] | a->s6_addr32[1]) |
695 #endif
696 		(__force unsigned long)(a->s6_addr32[2] ^
697 					cpu_to_be32(0x0000ffff))) == 0UL;
698 }
699 
700 static inline bool ipv6_addr_v4mapped_loopback(const struct in6_addr *a)
701 {
702 	return ipv6_addr_v4mapped(a) && ipv4_is_loopback(a->s6_addr32[3]);
703 }
704 
705 static inline u32 ipv6_portaddr_hash(const struct net *net,
706 				     const struct in6_addr *addr6,
707 				     unsigned int port)
708 {
709 	unsigned int hash, mix = net_hash_mix(net);
710 
711 	if (ipv6_addr_any(addr6))
712 		hash = jhash_1word(0, mix);
713 	else if (ipv6_addr_v4mapped(addr6))
714 		hash = jhash_1word((__force u32)addr6->s6_addr32[3], mix);
715 	else
716 		hash = jhash2((__force u32 *)addr6->s6_addr32, 4, mix);
717 
718 	return hash ^ port;
719 }
720 
721 /*
722  * Check for a RFC 4843 ORCHID address
723  * (Overlay Routable Cryptographic Hash Identifiers)
724  */
725 static inline bool ipv6_addr_orchid(const struct in6_addr *a)
726 {
727 	return (a->s6_addr32[0] & htonl(0xfffffff0)) == htonl(0x20010010);
728 }
729 
730 static inline bool ipv6_addr_is_multicast(const struct in6_addr *addr)
731 {
732 	return (addr->s6_addr32[0] & htonl(0xFF000000)) == htonl(0xFF000000);
733 }
734 
735 static inline void ipv6_addr_set_v4mapped(const __be32 addr,
736 					  struct in6_addr *v4mapped)
737 {
738 	ipv6_addr_set(v4mapped,
739 			0, 0,
740 			htonl(0x0000FFFF),
741 			addr);
742 }
743 
744 /*
745  * find the first different bit between two addresses
746  * length of address must be a multiple of 32bits
747  */
748 static inline int __ipv6_addr_diff32(const void *token1, const void *token2, int addrlen)
749 {
750 	const __be32 *a1 = token1, *a2 = token2;
751 	int i;
752 
753 	addrlen >>= 2;
754 
755 	for (i = 0; i < addrlen; i++) {
756 		__be32 xb = a1[i] ^ a2[i];
757 		if (xb)
758 			return i * 32 + 31 - __fls(ntohl(xb));
759 	}
760 
761 	/*
762 	 *	we should *never* get to this point since that
763 	 *	would mean the addrs are equal
764 	 *
765 	 *	However, we do get to it 8) And exacly, when
766 	 *	addresses are equal 8)
767 	 *
768 	 *	ip route add 1111::/128 via ...
769 	 *	ip route add 1111::/64 via ...
770 	 *	and we are here.
771 	 *
772 	 *	Ideally, this function should stop comparison
773 	 *	at prefix length. It does not, but it is still OK,
774 	 *	if returned value is greater than prefix length.
775 	 *					--ANK (980803)
776 	 */
777 	return addrlen << 5;
778 }
779 
780 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
781 static inline int __ipv6_addr_diff64(const void *token1, const void *token2, int addrlen)
782 {
783 	const __be64 *a1 = token1, *a2 = token2;
784 	int i;
785 
786 	addrlen >>= 3;
787 
788 	for (i = 0; i < addrlen; i++) {
789 		__be64 xb = a1[i] ^ a2[i];
790 		if (xb)
791 			return i * 64 + 63 - __fls(be64_to_cpu(xb));
792 	}
793 
794 	return addrlen << 6;
795 }
796 #endif
797 
798 static inline int __ipv6_addr_diff(const void *token1, const void *token2, int addrlen)
799 {
800 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
801 	if (__builtin_constant_p(addrlen) && !(addrlen & 7))
802 		return __ipv6_addr_diff64(token1, token2, addrlen);
803 #endif
804 	return __ipv6_addr_diff32(token1, token2, addrlen);
805 }
806 
807 static inline int ipv6_addr_diff(const struct in6_addr *a1, const struct in6_addr *a2)
808 {
809 	return __ipv6_addr_diff(a1, a2, sizeof(struct in6_addr));
810 }
811 
812 __be32 ipv6_select_ident(struct net *net,
813 			 const struct in6_addr *daddr,
814 			 const struct in6_addr *saddr);
815 __be32 ipv6_proxy_select_ident(struct net *net, struct sk_buff *skb);
816 
817 int ip6_dst_hoplimit(struct dst_entry *dst);
818 
819 static inline int ip6_sk_dst_hoplimit(struct ipv6_pinfo *np, struct flowi6 *fl6,
820 				      struct dst_entry *dst)
821 {
822 	int hlimit;
823 
824 	if (ipv6_addr_is_multicast(&fl6->daddr))
825 		hlimit = np->mcast_hops;
826 	else
827 		hlimit = np->hop_limit;
828 	if (hlimit < 0)
829 		hlimit = ip6_dst_hoplimit(dst);
830 	return hlimit;
831 }
832 
833 /* copy IPv6 saddr & daddr to flow_keys, possibly using 64bit load/store
834  * Equivalent to :	flow->v6addrs.src = iph->saddr;
835  *			flow->v6addrs.dst = iph->daddr;
836  */
837 static inline void iph_to_flow_copy_v6addrs(struct flow_keys *flow,
838 					    const struct ipv6hdr *iph)
839 {
840 	BUILD_BUG_ON(offsetof(typeof(flow->addrs), v6addrs.dst) !=
841 		     offsetof(typeof(flow->addrs), v6addrs.src) +
842 		     sizeof(flow->addrs.v6addrs.src));
843 	memcpy(&flow->addrs.v6addrs, &iph->saddr, sizeof(flow->addrs.v6addrs));
844 	flow->control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
845 }
846 
847 #if IS_ENABLED(CONFIG_IPV6)
848 
849 static inline bool ipv6_can_nonlocal_bind(struct net *net,
850 					  struct inet_sock *inet)
851 {
852 	return net->ipv6.sysctl.ip_nonlocal_bind ||
853 		inet->freebind || inet->transparent;
854 }
855 
856 /* Sysctl settings for net ipv6.auto_flowlabels */
857 #define IP6_AUTO_FLOW_LABEL_OFF		0
858 #define IP6_AUTO_FLOW_LABEL_OPTOUT	1
859 #define IP6_AUTO_FLOW_LABEL_OPTIN	2
860 #define IP6_AUTO_FLOW_LABEL_FORCED	3
861 
862 #define IP6_AUTO_FLOW_LABEL_MAX		IP6_AUTO_FLOW_LABEL_FORCED
863 
864 #define IP6_DEFAULT_AUTO_FLOW_LABELS	IP6_AUTO_FLOW_LABEL_OPTOUT
865 
866 static inline __be32 ip6_make_flowlabel(struct net *net, struct sk_buff *skb,
867 					__be32 flowlabel, bool autolabel,
868 					struct flowi6 *fl6)
869 {
870 	u32 hash;
871 
872 	/* @flowlabel may include more than a flow label, eg, the traffic class.
873 	 * Here we want only the flow label value.
874 	 */
875 	flowlabel &= IPV6_FLOWLABEL_MASK;
876 
877 	if (flowlabel ||
878 	    net->ipv6.sysctl.auto_flowlabels == IP6_AUTO_FLOW_LABEL_OFF ||
879 	    (!autolabel &&
880 	     net->ipv6.sysctl.auto_flowlabels != IP6_AUTO_FLOW_LABEL_FORCED))
881 		return flowlabel;
882 
883 	hash = skb_get_hash_flowi6(skb, fl6);
884 
885 	/* Since this is being sent on the wire obfuscate hash a bit
886 	 * to minimize possbility that any useful information to an
887 	 * attacker is leaked. Only lower 20 bits are relevant.
888 	 */
889 	hash = rol32(hash, 16);
890 
891 	flowlabel = (__force __be32)hash & IPV6_FLOWLABEL_MASK;
892 
893 	if (net->ipv6.sysctl.flowlabel_state_ranges)
894 		flowlabel |= IPV6_FLOWLABEL_STATELESS_FLAG;
895 
896 	return flowlabel;
897 }
898 
899 static inline int ip6_default_np_autolabel(struct net *net)
900 {
901 	switch (net->ipv6.sysctl.auto_flowlabels) {
902 	case IP6_AUTO_FLOW_LABEL_OFF:
903 	case IP6_AUTO_FLOW_LABEL_OPTIN:
904 	default:
905 		return 0;
906 	case IP6_AUTO_FLOW_LABEL_OPTOUT:
907 	case IP6_AUTO_FLOW_LABEL_FORCED:
908 		return 1;
909 	}
910 }
911 #else
912 static inline __be32 ip6_make_flowlabel(struct net *net, struct sk_buff *skb,
913 					__be32 flowlabel, bool autolabel,
914 					struct flowi6 *fl6)
915 {
916 	return flowlabel;
917 }
918 static inline int ip6_default_np_autolabel(struct net *net)
919 {
920 	return 0;
921 }
922 #endif
923 
924 #if IS_ENABLED(CONFIG_IPV6)
925 static inline int ip6_multipath_hash_policy(const struct net *net)
926 {
927 	return net->ipv6.sysctl.multipath_hash_policy;
928 }
929 static inline u32 ip6_multipath_hash_fields(const struct net *net)
930 {
931 	return net->ipv6.sysctl.multipath_hash_fields;
932 }
933 #else
934 static inline int ip6_multipath_hash_policy(const struct net *net)
935 {
936 	return 0;
937 }
938 static inline u32 ip6_multipath_hash_fields(const struct net *net)
939 {
940 	return 0;
941 }
942 #endif
943 
944 /*
945  *	Header manipulation
946  */
947 static inline void ip6_flow_hdr(struct ipv6hdr *hdr, unsigned int tclass,
948 				__be32 flowlabel)
949 {
950 	*(__be32 *)hdr = htonl(0x60000000 | (tclass << 20)) | flowlabel;
951 }
952 
953 static inline __be32 ip6_flowinfo(const struct ipv6hdr *hdr)
954 {
955 	return *(__be32 *)hdr & IPV6_FLOWINFO_MASK;
956 }
957 
958 static inline __be32 ip6_flowlabel(const struct ipv6hdr *hdr)
959 {
960 	return *(__be32 *)hdr & IPV6_FLOWLABEL_MASK;
961 }
962 
963 static inline u8 ip6_tclass(__be32 flowinfo)
964 {
965 	return ntohl(flowinfo & IPV6_TCLASS_MASK) >> IPV6_TCLASS_SHIFT;
966 }
967 
968 static inline __be32 ip6_make_flowinfo(unsigned int tclass, __be32 flowlabel)
969 {
970 	return htonl(tclass << IPV6_TCLASS_SHIFT) | flowlabel;
971 }
972 
973 static inline __be32 flowi6_get_flowlabel(const struct flowi6 *fl6)
974 {
975 	return fl6->flowlabel & IPV6_FLOWLABEL_MASK;
976 }
977 
978 /*
979  *	Prototypes exported by ipv6
980  */
981 
982 /*
983  *	rcv function (called from netdevice level)
984  */
985 
986 int ipv6_rcv(struct sk_buff *skb, struct net_device *dev,
987 	     struct packet_type *pt, struct net_device *orig_dev);
988 void ipv6_list_rcv(struct list_head *head, struct packet_type *pt,
989 		   struct net_device *orig_dev);
990 
991 int ip6_rcv_finish(struct net *net, struct sock *sk, struct sk_buff *skb);
992 
993 /*
994  *	upper-layer output functions
995  */
996 int ip6_xmit(const struct sock *sk, struct sk_buff *skb, struct flowi6 *fl6,
997 	     __u32 mark, struct ipv6_txoptions *opt, int tclass, u32 priority);
998 
999 int ip6_find_1stfragopt(struct sk_buff *skb, u8 **nexthdr);
1000 
1001 int ip6_append_data(struct sock *sk,
1002 		    int getfrag(void *from, char *to, int offset, int len,
1003 				int odd, struct sk_buff *skb),
1004 		    void *from, int length, int transhdrlen,
1005 		    struct ipcm6_cookie *ipc6, struct flowi6 *fl6,
1006 		    struct rt6_info *rt, unsigned int flags);
1007 
1008 int ip6_push_pending_frames(struct sock *sk);
1009 
1010 void ip6_flush_pending_frames(struct sock *sk);
1011 
1012 int ip6_send_skb(struct sk_buff *skb);
1013 
1014 struct sk_buff *__ip6_make_skb(struct sock *sk, struct sk_buff_head *queue,
1015 			       struct inet_cork_full *cork,
1016 			       struct inet6_cork *v6_cork);
1017 struct sk_buff *ip6_make_skb(struct sock *sk,
1018 			     int getfrag(void *from, char *to, int offset,
1019 					 int len, int odd, struct sk_buff *skb),
1020 			     void *from, int length, int transhdrlen,
1021 			     struct ipcm6_cookie *ipc6, struct flowi6 *fl6,
1022 			     struct rt6_info *rt, unsigned int flags,
1023 			     struct inet_cork_full *cork);
1024 
1025 static inline struct sk_buff *ip6_finish_skb(struct sock *sk)
1026 {
1027 	return __ip6_make_skb(sk, &sk->sk_write_queue, &inet_sk(sk)->cork,
1028 			      &inet6_sk(sk)->cork);
1029 }
1030 
1031 int ip6_dst_lookup(struct net *net, struct sock *sk, struct dst_entry **dst,
1032 		   struct flowi6 *fl6);
1033 struct dst_entry *ip6_dst_lookup_flow(struct net *net, const struct sock *sk, struct flowi6 *fl6,
1034 				      const struct in6_addr *final_dst);
1035 struct dst_entry *ip6_sk_dst_lookup_flow(struct sock *sk, struct flowi6 *fl6,
1036 					 const struct in6_addr *final_dst,
1037 					 bool connected);
1038 struct dst_entry *ip6_dst_lookup_tunnel(struct sk_buff *skb,
1039 					struct net_device *dev,
1040 					struct net *net, struct socket *sock,
1041 					struct in6_addr *saddr,
1042 					const struct ip_tunnel_info *info,
1043 					u8 protocol, bool use_cache);
1044 struct dst_entry *ip6_blackhole_route(struct net *net,
1045 				      struct dst_entry *orig_dst);
1046 
1047 /*
1048  *	skb processing functions
1049  */
1050 
1051 int ip6_output(struct net *net, struct sock *sk, struct sk_buff *skb);
1052 int ip6_forward(struct sk_buff *skb);
1053 int ip6_input(struct sk_buff *skb);
1054 int ip6_mc_input(struct sk_buff *skb);
1055 void ip6_protocol_deliver_rcu(struct net *net, struct sk_buff *skb, int nexthdr,
1056 			      bool have_final);
1057 
1058 int __ip6_local_out(struct net *net, struct sock *sk, struct sk_buff *skb);
1059 int ip6_local_out(struct net *net, struct sock *sk, struct sk_buff *skb);
1060 
1061 /*
1062  *	Extension header (options) processing
1063  */
1064 
1065 void ipv6_push_nfrag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt,
1066 			  u8 *proto, struct in6_addr **daddr_p,
1067 			  struct in6_addr *saddr);
1068 void ipv6_push_frag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt,
1069 			 u8 *proto);
1070 
1071 int ipv6_skip_exthdr(const struct sk_buff *, int start, u8 *nexthdrp,
1072 		     __be16 *frag_offp);
1073 
1074 bool ipv6_ext_hdr(u8 nexthdr);
1075 
1076 enum {
1077 	IP6_FH_F_FRAG		= (1 << 0),
1078 	IP6_FH_F_AUTH		= (1 << 1),
1079 	IP6_FH_F_SKIP_RH	= (1 << 2),
1080 };
1081 
1082 /* find specified header and get offset to it */
1083 int ipv6_find_hdr(const struct sk_buff *skb, unsigned int *offset, int target,
1084 		  unsigned short *fragoff, int *fragflg);
1085 
1086 int ipv6_find_tlv(const struct sk_buff *skb, int offset, int type);
1087 
1088 struct in6_addr *fl6_update_dst(struct flowi6 *fl6,
1089 				const struct ipv6_txoptions *opt,
1090 				struct in6_addr *orig);
1091 
1092 /*
1093  *	socket options (ipv6_sockglue.c)
1094  */
1095 
1096 int ipv6_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval,
1097 		    unsigned int optlen);
1098 int ipv6_getsockopt(struct sock *sk, int level, int optname,
1099 		    char __user *optval, int __user *optlen);
1100 
1101 int __ip6_datagram_connect(struct sock *sk, struct sockaddr *addr,
1102 			   int addr_len);
1103 int ip6_datagram_connect(struct sock *sk, struct sockaddr *addr, int addr_len);
1104 int ip6_datagram_connect_v6_only(struct sock *sk, struct sockaddr *addr,
1105 				 int addr_len);
1106 int ip6_datagram_dst_update(struct sock *sk, bool fix_sk_saddr);
1107 void ip6_datagram_release_cb(struct sock *sk);
1108 
1109 int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len,
1110 		    int *addr_len);
1111 int ipv6_recv_rxpmtu(struct sock *sk, struct msghdr *msg, int len,
1112 		     int *addr_len);
1113 void ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err, __be16 port,
1114 		     u32 info, u8 *payload);
1115 void ipv6_local_error(struct sock *sk, int err, struct flowi6 *fl6, u32 info);
1116 void ipv6_local_rxpmtu(struct sock *sk, struct flowi6 *fl6, u32 mtu);
1117 
1118 int inet6_release(struct socket *sock);
1119 int inet6_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len);
1120 int inet6_getname(struct socket *sock, struct sockaddr *uaddr,
1121 		  int peer);
1122 int inet6_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg);
1123 int inet6_compat_ioctl(struct socket *sock, unsigned int cmd,
1124 		unsigned long arg);
1125 
1126 int inet6_hash_connect(struct inet_timewait_death_row *death_row,
1127 			      struct sock *sk);
1128 int inet6_sendmsg(struct socket *sock, struct msghdr *msg, size_t size);
1129 int inet6_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
1130 		  int flags);
1131 
1132 /*
1133  * reassembly.c
1134  */
1135 extern const struct proto_ops inet6_stream_ops;
1136 extern const struct proto_ops inet6_dgram_ops;
1137 extern const struct proto_ops inet6_sockraw_ops;
1138 
1139 struct group_source_req;
1140 struct group_filter;
1141 
1142 int ip6_mc_source(int add, int omode, struct sock *sk,
1143 		  struct group_source_req *pgsr);
1144 int ip6_mc_msfilter(struct sock *sk, struct group_filter *gsf,
1145 		  struct sockaddr_storage *list);
1146 int ip6_mc_msfget(struct sock *sk, struct group_filter *gsf,
1147 		  struct sockaddr_storage __user *p);
1148 
1149 #ifdef CONFIG_PROC_FS
1150 int ac6_proc_init(struct net *net);
1151 void ac6_proc_exit(struct net *net);
1152 int raw6_proc_init(void);
1153 void raw6_proc_exit(void);
1154 int tcp6_proc_init(struct net *net);
1155 void tcp6_proc_exit(struct net *net);
1156 int udp6_proc_init(struct net *net);
1157 void udp6_proc_exit(struct net *net);
1158 int udplite6_proc_init(void);
1159 void udplite6_proc_exit(void);
1160 int ipv6_misc_proc_init(void);
1161 void ipv6_misc_proc_exit(void);
1162 int snmp6_register_dev(struct inet6_dev *idev);
1163 int snmp6_unregister_dev(struct inet6_dev *idev);
1164 
1165 #else
1166 static inline int ac6_proc_init(struct net *net) { return 0; }
1167 static inline void ac6_proc_exit(struct net *net) { }
1168 static inline int snmp6_register_dev(struct inet6_dev *idev) { return 0; }
1169 static inline int snmp6_unregister_dev(struct inet6_dev *idev) { return 0; }
1170 #endif
1171 
1172 #ifdef CONFIG_SYSCTL
1173 struct ctl_table *ipv6_icmp_sysctl_init(struct net *net);
1174 struct ctl_table *ipv6_route_sysctl_init(struct net *net);
1175 int ipv6_sysctl_register(void);
1176 void ipv6_sysctl_unregister(void);
1177 #endif
1178 
1179 int ipv6_sock_mc_join(struct sock *sk, int ifindex,
1180 		      const struct in6_addr *addr);
1181 int ipv6_sock_mc_join_ssm(struct sock *sk, int ifindex,
1182 			  const struct in6_addr *addr, unsigned int mode);
1183 int ipv6_sock_mc_drop(struct sock *sk, int ifindex,
1184 		      const struct in6_addr *addr);
1185 
1186 static inline int ip6_sock_set_v6only(struct sock *sk)
1187 {
1188 	if (inet_sk(sk)->inet_num)
1189 		return -EINVAL;
1190 	lock_sock(sk);
1191 	sk->sk_ipv6only = true;
1192 	release_sock(sk);
1193 	return 0;
1194 }
1195 
1196 static inline void ip6_sock_set_recverr(struct sock *sk)
1197 {
1198 	lock_sock(sk);
1199 	inet6_sk(sk)->recverr = true;
1200 	release_sock(sk);
1201 }
1202 
1203 static inline int __ip6_sock_set_addr_preferences(struct sock *sk, int val)
1204 {
1205 	unsigned int pref = 0;
1206 	unsigned int prefmask = ~0;
1207 
1208 	/* check PUBLIC/TMP/PUBTMP_DEFAULT conflicts */
1209 	switch (val & (IPV6_PREFER_SRC_PUBLIC |
1210 		       IPV6_PREFER_SRC_TMP |
1211 		       IPV6_PREFER_SRC_PUBTMP_DEFAULT)) {
1212 	case IPV6_PREFER_SRC_PUBLIC:
1213 		pref |= IPV6_PREFER_SRC_PUBLIC;
1214 		prefmask &= ~(IPV6_PREFER_SRC_PUBLIC |
1215 			      IPV6_PREFER_SRC_TMP);
1216 		break;
1217 	case IPV6_PREFER_SRC_TMP:
1218 		pref |= IPV6_PREFER_SRC_TMP;
1219 		prefmask &= ~(IPV6_PREFER_SRC_PUBLIC |
1220 			      IPV6_PREFER_SRC_TMP);
1221 		break;
1222 	case IPV6_PREFER_SRC_PUBTMP_DEFAULT:
1223 		prefmask &= ~(IPV6_PREFER_SRC_PUBLIC |
1224 			      IPV6_PREFER_SRC_TMP);
1225 		break;
1226 	case 0:
1227 		break;
1228 	default:
1229 		return -EINVAL;
1230 	}
1231 
1232 	/* check HOME/COA conflicts */
1233 	switch (val & (IPV6_PREFER_SRC_HOME | IPV6_PREFER_SRC_COA)) {
1234 	case IPV6_PREFER_SRC_HOME:
1235 		prefmask &= ~IPV6_PREFER_SRC_COA;
1236 		break;
1237 	case IPV6_PREFER_SRC_COA:
1238 		pref |= IPV6_PREFER_SRC_COA;
1239 		break;
1240 	case 0:
1241 		break;
1242 	default:
1243 		return -EINVAL;
1244 	}
1245 
1246 	/* check CGA/NONCGA conflicts */
1247 	switch (val & (IPV6_PREFER_SRC_CGA|IPV6_PREFER_SRC_NONCGA)) {
1248 	case IPV6_PREFER_SRC_CGA:
1249 	case IPV6_PREFER_SRC_NONCGA:
1250 	case 0:
1251 		break;
1252 	default:
1253 		return -EINVAL;
1254 	}
1255 
1256 	inet6_sk(sk)->srcprefs = (inet6_sk(sk)->srcprefs & prefmask) | pref;
1257 	return 0;
1258 }
1259 
1260 static inline int ip6_sock_set_addr_preferences(struct sock *sk, bool val)
1261 {
1262 	int ret;
1263 
1264 	lock_sock(sk);
1265 	ret = __ip6_sock_set_addr_preferences(sk, val);
1266 	release_sock(sk);
1267 	return ret;
1268 }
1269 
1270 static inline void ip6_sock_set_recvpktinfo(struct sock *sk)
1271 {
1272 	lock_sock(sk);
1273 	inet6_sk(sk)->rxopt.bits.rxinfo = true;
1274 	release_sock(sk);
1275 }
1276 
1277 #endif /* _NET_IPV6_H */
1278