xref: /openbmc/linux/include/net/ipv6.h (revision 7663edc1)
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_TCP		6	/* TCP segment. */
34 #define NEXTHDR_UDP		17	/* UDP message. */
35 #define NEXTHDR_IPV6		41	/* IPv6 in IPv6 */
36 #define NEXTHDR_ROUTING		43	/* Routing header. */
37 #define NEXTHDR_FRAGMENT	44	/* Fragmentation/reassembly header. */
38 #define NEXTHDR_GRE		47	/* GRE header. */
39 #define NEXTHDR_ESP		50	/* Encapsulating security payload. */
40 #define NEXTHDR_AUTH		51	/* Authentication header. */
41 #define NEXTHDR_ICMP		58	/* ICMP for IPv6. */
42 #define NEXTHDR_NONE		59	/* No next header */
43 #define NEXTHDR_DEST		60	/* Destination options header. */
44 #define NEXTHDR_SCTP		132	/* SCTP message. */
45 #define NEXTHDR_MOBILITY	135	/* Mobility header. */
46 
47 #define NEXTHDR_MAX		255
48 
49 #define IPV6_DEFAULT_HOPLIMIT   64
50 #define IPV6_DEFAULT_MCASTHOPS	1
51 
52 /* Limits on Hop-by-Hop and Destination options.
53  *
54  * Per RFC8200 there is no limit on the maximum number or lengths of options in
55  * Hop-by-Hop or Destination options other then the packet must fit in an MTU.
56  * We allow configurable limits in order to mitigate potential denial of
57  * service attacks.
58  *
59  * There are three limits that may be set:
60  *   - Limit the number of options in a Hop-by-Hop or Destination options
61  *     extension header
62  *   - Limit the byte length of a Hop-by-Hop or Destination options extension
63  *     header
64  *   - Disallow unknown options
65  *
66  * The limits are expressed in corresponding sysctls:
67  *
68  * ipv6.sysctl.max_dst_opts_cnt
69  * ipv6.sysctl.max_hbh_opts_cnt
70  * ipv6.sysctl.max_dst_opts_len
71  * ipv6.sysctl.max_hbh_opts_len
72  *
73  * max_*_opts_cnt is the number of TLVs that are allowed for Destination
74  * options or Hop-by-Hop options. If the number is less than zero then unknown
75  * TLVs are disallowed and the number of known options that are allowed is the
76  * absolute value. Setting the value to INT_MAX indicates no limit.
77  *
78  * max_*_opts_len is the length limit in bytes of a Destination or
79  * Hop-by-Hop options extension header. Setting the value to INT_MAX
80  * indicates no length limit.
81  *
82  * If a limit is exceeded when processing an extension header the packet is
83  * silently discarded.
84  */
85 
86 /* Default limits for Hop-by-Hop and Destination options */
87 #define IP6_DEFAULT_MAX_DST_OPTS_CNT	 8
88 #define IP6_DEFAULT_MAX_HBH_OPTS_CNT	 8
89 #define IP6_DEFAULT_MAX_DST_OPTS_LEN	 INT_MAX /* No limit */
90 #define IP6_DEFAULT_MAX_HBH_OPTS_LEN	 INT_MAX /* No limit */
91 
92 /*
93  *	Addr type
94  *
95  *	type	-	unicast | multicast
96  *	scope	-	local	| site	    | global
97  *	v4	-	compat
98  *	v4mapped
99  *	any
100  *	loopback
101  */
102 
103 #define IPV6_ADDR_ANY		0x0000U
104 
105 #define IPV6_ADDR_UNICAST	0x0001U
106 #define IPV6_ADDR_MULTICAST	0x0002U
107 
108 #define IPV6_ADDR_LOOPBACK	0x0010U
109 #define IPV6_ADDR_LINKLOCAL	0x0020U
110 #define IPV6_ADDR_SITELOCAL	0x0040U
111 
112 #define IPV6_ADDR_COMPATv4	0x0080U
113 
114 #define IPV6_ADDR_SCOPE_MASK	0x00f0U
115 
116 #define IPV6_ADDR_MAPPED	0x1000U
117 
118 /*
119  *	Addr scopes
120  */
121 #define IPV6_ADDR_MC_SCOPE(a)	\
122 	((a)->s6_addr[1] & 0x0f)	/* nonstandard */
123 #define __IPV6_ADDR_SCOPE_INVALID	-1
124 #define IPV6_ADDR_SCOPE_NODELOCAL	0x01
125 #define IPV6_ADDR_SCOPE_LINKLOCAL	0x02
126 #define IPV6_ADDR_SCOPE_SITELOCAL	0x05
127 #define IPV6_ADDR_SCOPE_ORGLOCAL	0x08
128 #define IPV6_ADDR_SCOPE_GLOBAL		0x0e
129 
130 /*
131  *	Addr flags
132  */
133 #define IPV6_ADDR_MC_FLAG_TRANSIENT(a)	\
134 	((a)->s6_addr[1] & 0x10)
135 #define IPV6_ADDR_MC_FLAG_PREFIX(a)	\
136 	((a)->s6_addr[1] & 0x20)
137 #define IPV6_ADDR_MC_FLAG_RENDEZVOUS(a)	\
138 	((a)->s6_addr[1] & 0x40)
139 
140 /*
141  *	fragmentation header
142  */
143 
144 struct frag_hdr {
145 	__u8	nexthdr;
146 	__u8	reserved;
147 	__be16	frag_off;
148 	__be32	identification;
149 };
150 
151 #define	IP6_MF		0x0001
152 #define	IP6_OFFSET	0xFFF8
153 
154 struct ip6_fraglist_iter {
155 	struct ipv6hdr	*tmp_hdr;
156 	struct sk_buff	*frag;
157 	int		offset;
158 	unsigned int	hlen;
159 	__be32		frag_id;
160 	u8		nexthdr;
161 };
162 
163 int ip6_fraglist_init(struct sk_buff *skb, unsigned int hlen, u8 *prevhdr,
164 		      u8 nexthdr, __be32 frag_id,
165 		      struct ip6_fraglist_iter *iter);
166 void ip6_fraglist_prepare(struct sk_buff *skb, struct ip6_fraglist_iter *iter);
167 
168 static inline struct sk_buff *ip6_fraglist_next(struct ip6_fraglist_iter *iter)
169 {
170 	struct sk_buff *skb = iter->frag;
171 
172 	iter->frag = skb->next;
173 	skb_mark_not_on_list(skb);
174 
175 	return skb;
176 }
177 
178 struct ip6_frag_state {
179 	u8		*prevhdr;
180 	unsigned int	hlen;
181 	unsigned int	mtu;
182 	unsigned int	left;
183 	int		offset;
184 	int		ptr;
185 	int		hroom;
186 	int		troom;
187 	__be32		frag_id;
188 	u8		nexthdr;
189 };
190 
191 void ip6_frag_init(struct sk_buff *skb, unsigned int hlen, unsigned int mtu,
192 		   unsigned short needed_tailroom, int hdr_room, u8 *prevhdr,
193 		   u8 nexthdr, __be32 frag_id, struct ip6_frag_state *state);
194 struct sk_buff *ip6_frag_next(struct sk_buff *skb,
195 			      struct ip6_frag_state *state);
196 
197 #define IP6_REPLY_MARK(net, mark) \
198 	((net)->ipv6.sysctl.fwmark_reflect ? (mark) : 0)
199 
200 #include <net/sock.h>
201 
202 /* sysctls */
203 extern int sysctl_mld_max_msf;
204 extern int sysctl_mld_qrv;
205 
206 #define _DEVINC(net, statname, mod, idev, field)			\
207 ({									\
208 	struct inet6_dev *_idev = (idev);				\
209 	if (likely(_idev != NULL))					\
210 		mod##SNMP_INC_STATS64((_idev)->stats.statname, (field));\
211 	mod##SNMP_INC_STATS64((net)->mib.statname##_statistics, (field));\
212 })
213 
214 /* per device counters are atomic_long_t */
215 #define _DEVINCATOMIC(net, statname, mod, idev, field)			\
216 ({									\
217 	struct inet6_dev *_idev = (idev);				\
218 	if (likely(_idev != NULL))					\
219 		SNMP_INC_STATS_ATOMIC_LONG((_idev)->stats.statname##dev, (field)); \
220 	mod##SNMP_INC_STATS((net)->mib.statname##_statistics, (field));\
221 })
222 
223 /* per device and per net counters are atomic_long_t */
224 #define _DEVINC_ATOMIC_ATOMIC(net, statname, idev, field)		\
225 ({									\
226 	struct inet6_dev *_idev = (idev);				\
227 	if (likely(_idev != NULL))					\
228 		SNMP_INC_STATS_ATOMIC_LONG((_idev)->stats.statname##dev, (field)); \
229 	SNMP_INC_STATS_ATOMIC_LONG((net)->mib.statname##_statistics, (field));\
230 })
231 
232 #define _DEVADD(net, statname, mod, idev, field, val)			\
233 ({									\
234 	struct inet6_dev *_idev = (idev);				\
235 	if (likely(_idev != NULL))					\
236 		mod##SNMP_ADD_STATS((_idev)->stats.statname, (field), (val)); \
237 	mod##SNMP_ADD_STATS((net)->mib.statname##_statistics, (field), (val));\
238 })
239 
240 #define _DEVUPD(net, statname, mod, idev, field, val)			\
241 ({									\
242 	struct inet6_dev *_idev = (idev);				\
243 	if (likely(_idev != NULL))					\
244 		mod##SNMP_UPD_PO_STATS((_idev)->stats.statname, field, (val)); \
245 	mod##SNMP_UPD_PO_STATS((net)->mib.statname##_statistics, field, (val));\
246 })
247 
248 /* MIBs */
249 
250 #define IP6_INC_STATS(net, idev,field)		\
251 		_DEVINC(net, ipv6, , idev, field)
252 #define __IP6_INC_STATS(net, idev,field)	\
253 		_DEVINC(net, ipv6, __, idev, field)
254 #define IP6_ADD_STATS(net, idev,field,val)	\
255 		_DEVADD(net, ipv6, , idev, field, val)
256 #define __IP6_ADD_STATS(net, idev,field,val)	\
257 		_DEVADD(net, ipv6, __, idev, field, val)
258 #define IP6_UPD_PO_STATS(net, idev,field,val)   \
259 		_DEVUPD(net, ipv6, , idev, field, val)
260 #define __IP6_UPD_PO_STATS(net, idev,field,val)   \
261 		_DEVUPD(net, ipv6, __, idev, field, val)
262 #define ICMP6_INC_STATS(net, idev, field)	\
263 		_DEVINCATOMIC(net, icmpv6, , idev, field)
264 #define __ICMP6_INC_STATS(net, idev, field)	\
265 		_DEVINCATOMIC(net, icmpv6, __, idev, field)
266 
267 #define ICMP6MSGOUT_INC_STATS(net, idev, field)		\
268 	_DEVINC_ATOMIC_ATOMIC(net, icmpv6msg, idev, field +256)
269 #define ICMP6MSGIN_INC_STATS(net, idev, field)	\
270 	_DEVINC_ATOMIC_ATOMIC(net, icmpv6msg, idev, field)
271 
272 struct ip6_ra_chain {
273 	struct ip6_ra_chain	*next;
274 	struct sock		*sk;
275 	int			sel;
276 	void			(*destructor)(struct sock *);
277 };
278 
279 extern struct ip6_ra_chain	*ip6_ra_chain;
280 extern rwlock_t ip6_ra_lock;
281 
282 /*
283    This structure is prepared by protocol, when parsing
284    ancillary data and passed to IPv6.
285  */
286 
287 struct ipv6_txoptions {
288 	refcount_t		refcnt;
289 	/* Length of this structure */
290 	int			tot_len;
291 
292 	/* length of extension headers   */
293 
294 	__u16			opt_flen;	/* after fragment hdr */
295 	__u16			opt_nflen;	/* before fragment hdr */
296 
297 	struct ipv6_opt_hdr	*hopopt;
298 	struct ipv6_opt_hdr	*dst0opt;
299 	struct ipv6_rt_hdr	*srcrt;	/* Routing Header */
300 	struct ipv6_opt_hdr	*dst1opt;
301 	struct rcu_head		rcu;
302 	/* Option buffer, as read by IPV6_PKTOPTIONS, starts here. */
303 };
304 
305 /* flowlabel_reflect sysctl values */
306 enum flowlabel_reflect {
307 	FLOWLABEL_REFLECT_ESTABLISHED		= 1,
308 	FLOWLABEL_REFLECT_TCP_RESET		= 2,
309 	FLOWLABEL_REFLECT_ICMPV6_ECHO_REPLIES	= 4,
310 };
311 
312 struct ip6_flowlabel {
313 	struct ip6_flowlabel __rcu *next;
314 	__be32			label;
315 	atomic_t		users;
316 	struct in6_addr		dst;
317 	struct ipv6_txoptions	*opt;
318 	unsigned long		linger;
319 	struct rcu_head		rcu;
320 	u8			share;
321 	union {
322 		struct pid *pid;
323 		kuid_t uid;
324 	} owner;
325 	unsigned long		lastuse;
326 	unsigned long		expires;
327 	struct net		*fl_net;
328 };
329 
330 #define IPV6_FLOWINFO_MASK		cpu_to_be32(0x0FFFFFFF)
331 #define IPV6_FLOWLABEL_MASK		cpu_to_be32(0x000FFFFF)
332 #define IPV6_FLOWLABEL_STATELESS_FLAG	cpu_to_be32(0x00080000)
333 
334 #define IPV6_TCLASS_MASK (IPV6_FLOWINFO_MASK & ~IPV6_FLOWLABEL_MASK)
335 #define IPV6_TCLASS_SHIFT	20
336 
337 struct ipv6_fl_socklist {
338 	struct ipv6_fl_socklist	__rcu	*next;
339 	struct ip6_flowlabel		*fl;
340 	struct rcu_head			rcu;
341 };
342 
343 struct ipcm6_cookie {
344 	struct sockcm_cookie sockc;
345 	__s16 hlimit;
346 	__s16 tclass;
347 	__s8  dontfrag;
348 	struct ipv6_txoptions *opt;
349 	__u16 gso_size;
350 };
351 
352 static inline void ipcm6_init(struct ipcm6_cookie *ipc6)
353 {
354 	*ipc6 = (struct ipcm6_cookie) {
355 		.hlimit = -1,
356 		.tclass = -1,
357 		.dontfrag = -1,
358 	};
359 }
360 
361 static inline void ipcm6_init_sk(struct ipcm6_cookie *ipc6,
362 				 const struct ipv6_pinfo *np)
363 {
364 	*ipc6 = (struct ipcm6_cookie) {
365 		.hlimit = -1,
366 		.tclass = np->tclass,
367 		.dontfrag = np->dontfrag,
368 	};
369 }
370 
371 static inline struct ipv6_txoptions *txopt_get(const struct ipv6_pinfo *np)
372 {
373 	struct ipv6_txoptions *opt;
374 
375 	rcu_read_lock();
376 	opt = rcu_dereference(np->opt);
377 	if (opt) {
378 		if (!refcount_inc_not_zero(&opt->refcnt))
379 			opt = NULL;
380 		else
381 			opt = rcu_pointer_handoff(opt);
382 	}
383 	rcu_read_unlock();
384 	return opt;
385 }
386 
387 static inline void txopt_put(struct ipv6_txoptions *opt)
388 {
389 	if (opt && refcount_dec_and_test(&opt->refcnt))
390 		kfree_rcu(opt, rcu);
391 }
392 
393 struct ip6_flowlabel *__fl6_sock_lookup(struct sock *sk, __be32 label);
394 
395 extern struct static_key_false_deferred ipv6_flowlabel_exclusive;
396 static inline struct ip6_flowlabel *fl6_sock_lookup(struct sock *sk,
397 						    __be32 label)
398 {
399 	if (static_branch_unlikely(&ipv6_flowlabel_exclusive.key))
400 		return __fl6_sock_lookup(sk, label) ? : ERR_PTR(-ENOENT);
401 
402 	return NULL;
403 }
404 
405 struct ipv6_txoptions *fl6_merge_options(struct ipv6_txoptions *opt_space,
406 					 struct ip6_flowlabel *fl,
407 					 struct ipv6_txoptions *fopt);
408 void fl6_free_socklist(struct sock *sk);
409 int ipv6_flowlabel_opt(struct sock *sk, sockptr_t optval, int optlen);
410 int ipv6_flowlabel_opt_get(struct sock *sk, struct in6_flowlabel_req *freq,
411 			   int flags);
412 int ip6_flowlabel_init(void);
413 void ip6_flowlabel_cleanup(void);
414 bool ip6_autoflowlabel(struct net *net, const struct ipv6_pinfo *np);
415 
416 static inline void fl6_sock_release(struct ip6_flowlabel *fl)
417 {
418 	if (fl)
419 		atomic_dec(&fl->users);
420 }
421 
422 void icmpv6_notify(struct sk_buff *skb, u8 type, u8 code, __be32 info);
423 
424 void icmpv6_push_pending_frames(struct sock *sk, struct flowi6 *fl6,
425 				struct icmp6hdr *thdr, int len);
426 
427 int ip6_ra_control(struct sock *sk, int sel);
428 
429 int ipv6_parse_hopopts(struct sk_buff *skb);
430 
431 struct ipv6_txoptions *ipv6_dup_options(struct sock *sk,
432 					struct ipv6_txoptions *opt);
433 struct ipv6_txoptions *ipv6_renew_options(struct sock *sk,
434 					  struct ipv6_txoptions *opt,
435 					  int newtype,
436 					  struct ipv6_opt_hdr *newopt);
437 struct ipv6_txoptions *ipv6_fixup_options(struct ipv6_txoptions *opt_space,
438 					  struct ipv6_txoptions *opt);
439 
440 bool ipv6_opt_accepted(const struct sock *sk, const struct sk_buff *skb,
441 		       const struct inet6_skb_parm *opt);
442 struct ipv6_txoptions *ipv6_update_options(struct sock *sk,
443 					   struct ipv6_txoptions *opt);
444 
445 static inline bool ipv6_accept_ra(struct inet6_dev *idev)
446 {
447 	/* If forwarding is enabled, RA are not accepted unless the special
448 	 * hybrid mode (accept_ra=2) is enabled.
449 	 */
450 	return idev->cnf.forwarding ? idev->cnf.accept_ra == 2 :
451 	    idev->cnf.accept_ra;
452 }
453 
454 #define IPV6_FRAG_HIGH_THRESH	(4 * 1024*1024)	/* 4194304 */
455 #define IPV6_FRAG_LOW_THRESH	(3 * 1024*1024)	/* 3145728 */
456 #define IPV6_FRAG_TIMEOUT	(60 * HZ)	/* 60 seconds */
457 
458 int __ipv6_addr_type(const struct in6_addr *addr);
459 static inline int ipv6_addr_type(const struct in6_addr *addr)
460 {
461 	return __ipv6_addr_type(addr) & 0xffff;
462 }
463 
464 static inline int ipv6_addr_scope(const struct in6_addr *addr)
465 {
466 	return __ipv6_addr_type(addr) & IPV6_ADDR_SCOPE_MASK;
467 }
468 
469 static inline int __ipv6_addr_src_scope(int type)
470 {
471 	return (type == IPV6_ADDR_ANY) ? __IPV6_ADDR_SCOPE_INVALID : (type >> 16);
472 }
473 
474 static inline int ipv6_addr_src_scope(const struct in6_addr *addr)
475 {
476 	return __ipv6_addr_src_scope(__ipv6_addr_type(addr));
477 }
478 
479 static inline bool __ipv6_addr_needs_scope_id(int type)
480 {
481 	return type & IPV6_ADDR_LINKLOCAL ||
482 	       (type & IPV6_ADDR_MULTICAST &&
483 		(type & (IPV6_ADDR_LOOPBACK|IPV6_ADDR_LINKLOCAL)));
484 }
485 
486 static inline __u32 ipv6_iface_scope_id(const struct in6_addr *addr, int iface)
487 {
488 	return __ipv6_addr_needs_scope_id(__ipv6_addr_type(addr)) ? iface : 0;
489 }
490 
491 static inline int ipv6_addr_cmp(const struct in6_addr *a1, const struct in6_addr *a2)
492 {
493 	return memcmp(a1, a2, sizeof(struct in6_addr));
494 }
495 
496 static inline bool
497 ipv6_masked_addr_cmp(const struct in6_addr *a1, const struct in6_addr *m,
498 		     const struct in6_addr *a2)
499 {
500 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
501 	const unsigned long *ul1 = (const unsigned long *)a1;
502 	const unsigned long *ulm = (const unsigned long *)m;
503 	const unsigned long *ul2 = (const unsigned long *)a2;
504 
505 	return !!(((ul1[0] ^ ul2[0]) & ulm[0]) |
506 		  ((ul1[1] ^ ul2[1]) & ulm[1]));
507 #else
508 	return !!(((a1->s6_addr32[0] ^ a2->s6_addr32[0]) & m->s6_addr32[0]) |
509 		  ((a1->s6_addr32[1] ^ a2->s6_addr32[1]) & m->s6_addr32[1]) |
510 		  ((a1->s6_addr32[2] ^ a2->s6_addr32[2]) & m->s6_addr32[2]) |
511 		  ((a1->s6_addr32[3] ^ a2->s6_addr32[3]) & m->s6_addr32[3]));
512 #endif
513 }
514 
515 static inline void ipv6_addr_prefix(struct in6_addr *pfx,
516 				    const struct in6_addr *addr,
517 				    int plen)
518 {
519 	/* caller must guarantee 0 <= plen <= 128 */
520 	int o = plen >> 3,
521 	    b = plen & 0x7;
522 
523 	memset(pfx->s6_addr, 0, sizeof(pfx->s6_addr));
524 	memcpy(pfx->s6_addr, addr, o);
525 	if (b != 0)
526 		pfx->s6_addr[o] = addr->s6_addr[o] & (0xff00 >> b);
527 }
528 
529 static inline void ipv6_addr_prefix_copy(struct in6_addr *addr,
530 					 const struct in6_addr *pfx,
531 					 int plen)
532 {
533 	/* caller must guarantee 0 <= plen <= 128 */
534 	int o = plen >> 3,
535 	    b = plen & 0x7;
536 
537 	memcpy(addr->s6_addr, pfx, o);
538 	if (b != 0) {
539 		addr->s6_addr[o] &= ~(0xff00 >> b);
540 		addr->s6_addr[o] |= (pfx->s6_addr[o] & (0xff00 >> b));
541 	}
542 }
543 
544 static inline void __ipv6_addr_set_half(__be32 *addr,
545 					__be32 wh, __be32 wl)
546 {
547 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
548 #if defined(__BIG_ENDIAN)
549 	if (__builtin_constant_p(wh) && __builtin_constant_p(wl)) {
550 		*(__force u64 *)addr = ((__force u64)(wh) << 32 | (__force u64)(wl));
551 		return;
552 	}
553 #elif defined(__LITTLE_ENDIAN)
554 	if (__builtin_constant_p(wl) && __builtin_constant_p(wh)) {
555 		*(__force u64 *)addr = ((__force u64)(wl) << 32 | (__force u64)(wh));
556 		return;
557 	}
558 #endif
559 #endif
560 	addr[0] = wh;
561 	addr[1] = wl;
562 }
563 
564 static inline void ipv6_addr_set(struct in6_addr *addr,
565 				     __be32 w1, __be32 w2,
566 				     __be32 w3, __be32 w4)
567 {
568 	__ipv6_addr_set_half(&addr->s6_addr32[0], w1, w2);
569 	__ipv6_addr_set_half(&addr->s6_addr32[2], w3, w4);
570 }
571 
572 static inline bool ipv6_addr_equal(const struct in6_addr *a1,
573 				   const struct in6_addr *a2)
574 {
575 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
576 	const unsigned long *ul1 = (const unsigned long *)a1;
577 	const unsigned long *ul2 = (const unsigned long *)a2;
578 
579 	return ((ul1[0] ^ ul2[0]) | (ul1[1] ^ ul2[1])) == 0UL;
580 #else
581 	return ((a1->s6_addr32[0] ^ a2->s6_addr32[0]) |
582 		(a1->s6_addr32[1] ^ a2->s6_addr32[1]) |
583 		(a1->s6_addr32[2] ^ a2->s6_addr32[2]) |
584 		(a1->s6_addr32[3] ^ a2->s6_addr32[3])) == 0;
585 #endif
586 }
587 
588 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
589 static inline bool __ipv6_prefix_equal64_half(const __be64 *a1,
590 					      const __be64 *a2,
591 					      unsigned int len)
592 {
593 	if (len && ((*a1 ^ *a2) & cpu_to_be64((~0UL) << (64 - len))))
594 		return false;
595 	return true;
596 }
597 
598 static inline bool ipv6_prefix_equal(const struct in6_addr *addr1,
599 				     const struct in6_addr *addr2,
600 				     unsigned int prefixlen)
601 {
602 	const __be64 *a1 = (const __be64 *)addr1;
603 	const __be64 *a2 = (const __be64 *)addr2;
604 
605 	if (prefixlen >= 64) {
606 		if (a1[0] ^ a2[0])
607 			return false;
608 		return __ipv6_prefix_equal64_half(a1 + 1, a2 + 1, prefixlen - 64);
609 	}
610 	return __ipv6_prefix_equal64_half(a1, a2, prefixlen);
611 }
612 #else
613 static inline bool ipv6_prefix_equal(const struct in6_addr *addr1,
614 				     const struct in6_addr *addr2,
615 				     unsigned int prefixlen)
616 {
617 	const __be32 *a1 = addr1->s6_addr32;
618 	const __be32 *a2 = addr2->s6_addr32;
619 	unsigned int pdw, pbi;
620 
621 	/* check complete u32 in prefix */
622 	pdw = prefixlen >> 5;
623 	if (pdw && memcmp(a1, a2, pdw << 2))
624 		return false;
625 
626 	/* check incomplete u32 in prefix */
627 	pbi = prefixlen & 0x1f;
628 	if (pbi && ((a1[pdw] ^ a2[pdw]) & htonl((0xffffffff) << (32 - pbi))))
629 		return false;
630 
631 	return true;
632 }
633 #endif
634 
635 static inline bool ipv6_addr_any(const struct in6_addr *a)
636 {
637 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
638 	const unsigned long *ul = (const unsigned long *)a;
639 
640 	return (ul[0] | ul[1]) == 0UL;
641 #else
642 	return (a->s6_addr32[0] | a->s6_addr32[1] |
643 		a->s6_addr32[2] | a->s6_addr32[3]) == 0;
644 #endif
645 }
646 
647 static inline u32 ipv6_addr_hash(const struct in6_addr *a)
648 {
649 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
650 	const unsigned long *ul = (const unsigned long *)a;
651 	unsigned long x = ul[0] ^ ul[1];
652 
653 	return (u32)(x ^ (x >> 32));
654 #else
655 	return (__force u32)(a->s6_addr32[0] ^ a->s6_addr32[1] ^
656 			     a->s6_addr32[2] ^ a->s6_addr32[3]);
657 #endif
658 }
659 
660 /* more secured version of ipv6_addr_hash() */
661 static inline u32 __ipv6_addr_jhash(const struct in6_addr *a, const u32 initval)
662 {
663 	u32 v = (__force u32)a->s6_addr32[0] ^ (__force u32)a->s6_addr32[1];
664 
665 	return jhash_3words(v,
666 			    (__force u32)a->s6_addr32[2],
667 			    (__force u32)a->s6_addr32[3],
668 			    initval);
669 }
670 
671 static inline bool ipv6_addr_loopback(const struct in6_addr *a)
672 {
673 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
674 	const __be64 *be = (const __be64 *)a;
675 
676 	return (be[0] | (be[1] ^ cpu_to_be64(1))) == 0UL;
677 #else
678 	return (a->s6_addr32[0] | a->s6_addr32[1] |
679 		a->s6_addr32[2] | (a->s6_addr32[3] ^ cpu_to_be32(1))) == 0;
680 #endif
681 }
682 
683 /*
684  * Note that we must __force cast these to unsigned long to make sparse happy,
685  * since all of the endian-annotated types are fixed size regardless of arch.
686  */
687 static inline bool ipv6_addr_v4mapped(const struct in6_addr *a)
688 {
689 	return (
690 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
691 		*(unsigned long *)a |
692 #else
693 		(__force unsigned long)(a->s6_addr32[0] | a->s6_addr32[1]) |
694 #endif
695 		(__force unsigned long)(a->s6_addr32[2] ^
696 					cpu_to_be32(0x0000ffff))) == 0UL;
697 }
698 
699 static inline bool ipv6_addr_v4mapped_loopback(const struct in6_addr *a)
700 {
701 	return ipv6_addr_v4mapped(a) && ipv4_is_loopback(a->s6_addr32[3]);
702 }
703 
704 static inline u32 ipv6_portaddr_hash(const struct net *net,
705 				     const struct in6_addr *addr6,
706 				     unsigned int port)
707 {
708 	unsigned int hash, mix = net_hash_mix(net);
709 
710 	if (ipv6_addr_any(addr6))
711 		hash = jhash_1word(0, mix);
712 	else if (ipv6_addr_v4mapped(addr6))
713 		hash = jhash_1word((__force u32)addr6->s6_addr32[3], mix);
714 	else
715 		hash = jhash2((__force u32 *)addr6->s6_addr32, 4, mix);
716 
717 	return hash ^ port;
718 }
719 
720 /*
721  * Check for a RFC 4843 ORCHID address
722  * (Overlay Routable Cryptographic Hash Identifiers)
723  */
724 static inline bool ipv6_addr_orchid(const struct in6_addr *a)
725 {
726 	return (a->s6_addr32[0] & htonl(0xfffffff0)) == htonl(0x20010010);
727 }
728 
729 static inline bool ipv6_addr_is_multicast(const struct in6_addr *addr)
730 {
731 	return (addr->s6_addr32[0] & htonl(0xFF000000)) == htonl(0xFF000000);
732 }
733 
734 static inline void ipv6_addr_set_v4mapped(const __be32 addr,
735 					  struct in6_addr *v4mapped)
736 {
737 	ipv6_addr_set(v4mapped,
738 			0, 0,
739 			htonl(0x0000FFFF),
740 			addr);
741 }
742 
743 /*
744  * find the first different bit between two addresses
745  * length of address must be a multiple of 32bits
746  */
747 static inline int __ipv6_addr_diff32(const void *token1, const void *token2, int addrlen)
748 {
749 	const __be32 *a1 = token1, *a2 = token2;
750 	int i;
751 
752 	addrlen >>= 2;
753 
754 	for (i = 0; i < addrlen; i++) {
755 		__be32 xb = a1[i] ^ a2[i];
756 		if (xb)
757 			return i * 32 + 31 - __fls(ntohl(xb));
758 	}
759 
760 	/*
761 	 *	we should *never* get to this point since that
762 	 *	would mean the addrs are equal
763 	 *
764 	 *	However, we do get to it 8) And exacly, when
765 	 *	addresses are equal 8)
766 	 *
767 	 *	ip route add 1111::/128 via ...
768 	 *	ip route add 1111::/64 via ...
769 	 *	and we are here.
770 	 *
771 	 *	Ideally, this function should stop comparison
772 	 *	at prefix length. It does not, but it is still OK,
773 	 *	if returned value is greater than prefix length.
774 	 *					--ANK (980803)
775 	 */
776 	return addrlen << 5;
777 }
778 
779 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
780 static inline int __ipv6_addr_diff64(const void *token1, const void *token2, int addrlen)
781 {
782 	const __be64 *a1 = token1, *a2 = token2;
783 	int i;
784 
785 	addrlen >>= 3;
786 
787 	for (i = 0; i < addrlen; i++) {
788 		__be64 xb = a1[i] ^ a2[i];
789 		if (xb)
790 			return i * 64 + 63 - __fls(be64_to_cpu(xb));
791 	}
792 
793 	return addrlen << 6;
794 }
795 #endif
796 
797 static inline int __ipv6_addr_diff(const void *token1, const void *token2, int addrlen)
798 {
799 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
800 	if (__builtin_constant_p(addrlen) && !(addrlen & 7))
801 		return __ipv6_addr_diff64(token1, token2, addrlen);
802 #endif
803 	return __ipv6_addr_diff32(token1, token2, addrlen);
804 }
805 
806 static inline int ipv6_addr_diff(const struct in6_addr *a1, const struct in6_addr *a2)
807 {
808 	return __ipv6_addr_diff(a1, a2, sizeof(struct in6_addr));
809 }
810 
811 __be32 ipv6_select_ident(struct net *net,
812 			 const struct in6_addr *daddr,
813 			 const struct in6_addr *saddr);
814 __be32 ipv6_proxy_select_ident(struct net *net, struct sk_buff *skb);
815 
816 int ip6_dst_hoplimit(struct dst_entry *dst);
817 
818 static inline int ip6_sk_dst_hoplimit(struct ipv6_pinfo *np, struct flowi6 *fl6,
819 				      struct dst_entry *dst)
820 {
821 	int hlimit;
822 
823 	if (ipv6_addr_is_multicast(&fl6->daddr))
824 		hlimit = np->mcast_hops;
825 	else
826 		hlimit = np->hop_limit;
827 	if (hlimit < 0)
828 		hlimit = ip6_dst_hoplimit(dst);
829 	return hlimit;
830 }
831 
832 /* copy IPv6 saddr & daddr to flow_keys, possibly using 64bit load/store
833  * Equivalent to :	flow->v6addrs.src = iph->saddr;
834  *			flow->v6addrs.dst = iph->daddr;
835  */
836 static inline void iph_to_flow_copy_v6addrs(struct flow_keys *flow,
837 					    const struct ipv6hdr *iph)
838 {
839 	BUILD_BUG_ON(offsetof(typeof(flow->addrs), v6addrs.dst) !=
840 		     offsetof(typeof(flow->addrs), v6addrs.src) +
841 		     sizeof(flow->addrs.v6addrs.src));
842 	memcpy(&flow->addrs.v6addrs, &iph->saddr, sizeof(flow->addrs.v6addrs));
843 	flow->control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
844 }
845 
846 #if IS_ENABLED(CONFIG_IPV6)
847 
848 static inline bool ipv6_can_nonlocal_bind(struct net *net,
849 					  struct inet_sock *inet)
850 {
851 	return net->ipv6.sysctl.ip_nonlocal_bind ||
852 		inet->freebind || inet->transparent;
853 }
854 
855 /* Sysctl settings for net ipv6.auto_flowlabels */
856 #define IP6_AUTO_FLOW_LABEL_OFF		0
857 #define IP6_AUTO_FLOW_LABEL_OPTOUT	1
858 #define IP6_AUTO_FLOW_LABEL_OPTIN	2
859 #define IP6_AUTO_FLOW_LABEL_FORCED	3
860 
861 #define IP6_AUTO_FLOW_LABEL_MAX		IP6_AUTO_FLOW_LABEL_FORCED
862 
863 #define IP6_DEFAULT_AUTO_FLOW_LABELS	IP6_AUTO_FLOW_LABEL_OPTOUT
864 
865 static inline __be32 ip6_make_flowlabel(struct net *net, struct sk_buff *skb,
866 					__be32 flowlabel, bool autolabel,
867 					struct flowi6 *fl6)
868 {
869 	u32 hash;
870 
871 	/* @flowlabel may include more than a flow label, eg, the traffic class.
872 	 * Here we want only the flow label value.
873 	 */
874 	flowlabel &= IPV6_FLOWLABEL_MASK;
875 
876 	if (flowlabel ||
877 	    net->ipv6.sysctl.auto_flowlabels == IP6_AUTO_FLOW_LABEL_OFF ||
878 	    (!autolabel &&
879 	     net->ipv6.sysctl.auto_flowlabels != IP6_AUTO_FLOW_LABEL_FORCED))
880 		return flowlabel;
881 
882 	hash = skb_get_hash_flowi6(skb, fl6);
883 
884 	/* Since this is being sent on the wire obfuscate hash a bit
885 	 * to minimize possbility that any useful information to an
886 	 * attacker is leaked. Only lower 20 bits are relevant.
887 	 */
888 	hash = rol32(hash, 16);
889 
890 	flowlabel = (__force __be32)hash & IPV6_FLOWLABEL_MASK;
891 
892 	if (net->ipv6.sysctl.flowlabel_state_ranges)
893 		flowlabel |= IPV6_FLOWLABEL_STATELESS_FLAG;
894 
895 	return flowlabel;
896 }
897 
898 static inline int ip6_default_np_autolabel(struct net *net)
899 {
900 	switch (net->ipv6.sysctl.auto_flowlabels) {
901 	case IP6_AUTO_FLOW_LABEL_OFF:
902 	case IP6_AUTO_FLOW_LABEL_OPTIN:
903 	default:
904 		return 0;
905 	case IP6_AUTO_FLOW_LABEL_OPTOUT:
906 	case IP6_AUTO_FLOW_LABEL_FORCED:
907 		return 1;
908 	}
909 }
910 #else
911 static inline __be32 ip6_make_flowlabel(struct net *net, struct sk_buff *skb,
912 					__be32 flowlabel, bool autolabel,
913 					struct flowi6 *fl6)
914 {
915 	return flowlabel;
916 }
917 static inline int ip6_default_np_autolabel(struct net *net)
918 {
919 	return 0;
920 }
921 #endif
922 
923 #if IS_ENABLED(CONFIG_IPV6)
924 static inline int ip6_multipath_hash_policy(const struct net *net)
925 {
926 	return net->ipv6.sysctl.multipath_hash_policy;
927 }
928 #else
929 static inline int ip6_multipath_hash_policy(const struct net *net)
930 {
931 	return 0;
932 }
933 #endif
934 
935 /*
936  *	Header manipulation
937  */
938 static inline void ip6_flow_hdr(struct ipv6hdr *hdr, unsigned int tclass,
939 				__be32 flowlabel)
940 {
941 	*(__be32 *)hdr = htonl(0x60000000 | (tclass << 20)) | flowlabel;
942 }
943 
944 static inline __be32 ip6_flowinfo(const struct ipv6hdr *hdr)
945 {
946 	return *(__be32 *)hdr & IPV6_FLOWINFO_MASK;
947 }
948 
949 static inline __be32 ip6_flowlabel(const struct ipv6hdr *hdr)
950 {
951 	return *(__be32 *)hdr & IPV6_FLOWLABEL_MASK;
952 }
953 
954 static inline u8 ip6_tclass(__be32 flowinfo)
955 {
956 	return ntohl(flowinfo & IPV6_TCLASS_MASK) >> IPV6_TCLASS_SHIFT;
957 }
958 
959 static inline __be32 ip6_make_flowinfo(unsigned int tclass, __be32 flowlabel)
960 {
961 	return htonl(tclass << IPV6_TCLASS_SHIFT) | flowlabel;
962 }
963 
964 static inline __be32 flowi6_get_flowlabel(const struct flowi6 *fl6)
965 {
966 	return fl6->flowlabel & IPV6_FLOWLABEL_MASK;
967 }
968 
969 /*
970  *	Prototypes exported by ipv6
971  */
972 
973 /*
974  *	rcv function (called from netdevice level)
975  */
976 
977 int ipv6_rcv(struct sk_buff *skb, struct net_device *dev,
978 	     struct packet_type *pt, struct net_device *orig_dev);
979 void ipv6_list_rcv(struct list_head *head, struct packet_type *pt,
980 		   struct net_device *orig_dev);
981 
982 int ip6_rcv_finish(struct net *net, struct sock *sk, struct sk_buff *skb);
983 
984 /*
985  *	upper-layer output functions
986  */
987 int ip6_xmit(const struct sock *sk, struct sk_buff *skb, struct flowi6 *fl6,
988 	     __u32 mark, struct ipv6_txoptions *opt, int tclass, u32 priority);
989 
990 int ip6_find_1stfragopt(struct sk_buff *skb, u8 **nexthdr);
991 
992 int ip6_append_data(struct sock *sk,
993 		    int getfrag(void *from, char *to, int offset, int len,
994 				int odd, struct sk_buff *skb),
995 		    void *from, int length, int transhdrlen,
996 		    struct ipcm6_cookie *ipc6, struct flowi6 *fl6,
997 		    struct rt6_info *rt, unsigned int flags);
998 
999 int ip6_push_pending_frames(struct sock *sk);
1000 
1001 void ip6_flush_pending_frames(struct sock *sk);
1002 
1003 int ip6_send_skb(struct sk_buff *skb);
1004 
1005 struct sk_buff *__ip6_make_skb(struct sock *sk, struct sk_buff_head *queue,
1006 			       struct inet_cork_full *cork,
1007 			       struct inet6_cork *v6_cork);
1008 struct sk_buff *ip6_make_skb(struct sock *sk,
1009 			     int getfrag(void *from, char *to, int offset,
1010 					 int len, int odd, struct sk_buff *skb),
1011 			     void *from, int length, int transhdrlen,
1012 			     struct ipcm6_cookie *ipc6, struct flowi6 *fl6,
1013 			     struct rt6_info *rt, unsigned int flags,
1014 			     struct inet_cork_full *cork);
1015 
1016 static inline struct sk_buff *ip6_finish_skb(struct sock *sk)
1017 {
1018 	return __ip6_make_skb(sk, &sk->sk_write_queue, &inet_sk(sk)->cork,
1019 			      &inet6_sk(sk)->cork);
1020 }
1021 
1022 int ip6_dst_lookup(struct net *net, struct sock *sk, struct dst_entry **dst,
1023 		   struct flowi6 *fl6);
1024 struct dst_entry *ip6_dst_lookup_flow(struct net *net, const struct sock *sk, struct flowi6 *fl6,
1025 				      const struct in6_addr *final_dst);
1026 struct dst_entry *ip6_sk_dst_lookup_flow(struct sock *sk, struct flowi6 *fl6,
1027 					 const struct in6_addr *final_dst,
1028 					 bool connected);
1029 struct dst_entry *ip6_dst_lookup_tunnel(struct sk_buff *skb,
1030 					struct net_device *dev,
1031 					struct net *net, struct socket *sock,
1032 					struct in6_addr *saddr,
1033 					const struct ip_tunnel_info *info,
1034 					u8 protocol, bool use_cache);
1035 struct dst_entry *ip6_blackhole_route(struct net *net,
1036 				      struct dst_entry *orig_dst);
1037 
1038 /*
1039  *	skb processing functions
1040  */
1041 
1042 int ip6_output(struct net *net, struct sock *sk, struct sk_buff *skb);
1043 int ip6_forward(struct sk_buff *skb);
1044 int ip6_input(struct sk_buff *skb);
1045 int ip6_mc_input(struct sk_buff *skb);
1046 void ip6_protocol_deliver_rcu(struct net *net, struct sk_buff *skb, int nexthdr,
1047 			      bool have_final);
1048 
1049 int __ip6_local_out(struct net *net, struct sock *sk, struct sk_buff *skb);
1050 int ip6_local_out(struct net *net, struct sock *sk, struct sk_buff *skb);
1051 
1052 /*
1053  *	Extension header (options) processing
1054  */
1055 
1056 void ipv6_push_nfrag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt,
1057 			  u8 *proto, struct in6_addr **daddr_p,
1058 			  struct in6_addr *saddr);
1059 void ipv6_push_frag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt,
1060 			 u8 *proto);
1061 
1062 int ipv6_skip_exthdr(const struct sk_buff *, int start, u8 *nexthdrp,
1063 		     __be16 *frag_offp);
1064 
1065 bool ipv6_ext_hdr(u8 nexthdr);
1066 
1067 enum {
1068 	IP6_FH_F_FRAG		= (1 << 0),
1069 	IP6_FH_F_AUTH		= (1 << 1),
1070 	IP6_FH_F_SKIP_RH	= (1 << 2),
1071 };
1072 
1073 /* find specified header and get offset to it */
1074 int ipv6_find_hdr(const struct sk_buff *skb, unsigned int *offset, int target,
1075 		  unsigned short *fragoff, int *fragflg);
1076 
1077 int ipv6_find_tlv(const struct sk_buff *skb, int offset, int type);
1078 
1079 struct in6_addr *fl6_update_dst(struct flowi6 *fl6,
1080 				const struct ipv6_txoptions *opt,
1081 				struct in6_addr *orig);
1082 
1083 /*
1084  *	socket options (ipv6_sockglue.c)
1085  */
1086 
1087 int ipv6_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval,
1088 		    unsigned int optlen);
1089 int ipv6_getsockopt(struct sock *sk, int level, int optname,
1090 		    char __user *optval, int __user *optlen);
1091 
1092 int __ip6_datagram_connect(struct sock *sk, struct sockaddr *addr,
1093 			   int addr_len);
1094 int ip6_datagram_connect(struct sock *sk, struct sockaddr *addr, int addr_len);
1095 int ip6_datagram_connect_v6_only(struct sock *sk, struct sockaddr *addr,
1096 				 int addr_len);
1097 int ip6_datagram_dst_update(struct sock *sk, bool fix_sk_saddr);
1098 void ip6_datagram_release_cb(struct sock *sk);
1099 
1100 int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len,
1101 		    int *addr_len);
1102 int ipv6_recv_rxpmtu(struct sock *sk, struct msghdr *msg, int len,
1103 		     int *addr_len);
1104 void ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err, __be16 port,
1105 		     u32 info, u8 *payload);
1106 void ipv6_local_error(struct sock *sk, int err, struct flowi6 *fl6, u32 info);
1107 void ipv6_local_rxpmtu(struct sock *sk, struct flowi6 *fl6, u32 mtu);
1108 
1109 int inet6_release(struct socket *sock);
1110 int inet6_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len);
1111 int inet6_getname(struct socket *sock, struct sockaddr *uaddr,
1112 		  int peer);
1113 int inet6_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg);
1114 int inet6_compat_ioctl(struct socket *sock, unsigned int cmd,
1115 		unsigned long arg);
1116 
1117 int inet6_hash_connect(struct inet_timewait_death_row *death_row,
1118 			      struct sock *sk);
1119 int inet6_sendmsg(struct socket *sock, struct msghdr *msg, size_t size);
1120 int inet6_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
1121 		  int flags);
1122 
1123 /*
1124  * reassembly.c
1125  */
1126 extern const struct proto_ops inet6_stream_ops;
1127 extern const struct proto_ops inet6_dgram_ops;
1128 extern const struct proto_ops inet6_sockraw_ops;
1129 
1130 struct group_source_req;
1131 struct group_filter;
1132 
1133 int ip6_mc_source(int add, int omode, struct sock *sk,
1134 		  struct group_source_req *pgsr);
1135 int ip6_mc_msfilter(struct sock *sk, struct group_filter *gsf,
1136 		  struct sockaddr_storage *list);
1137 int ip6_mc_msfget(struct sock *sk, struct group_filter *gsf,
1138 		  struct sockaddr_storage __user *p);
1139 
1140 #ifdef CONFIG_PROC_FS
1141 int ac6_proc_init(struct net *net);
1142 void ac6_proc_exit(struct net *net);
1143 int raw6_proc_init(void);
1144 void raw6_proc_exit(void);
1145 int tcp6_proc_init(struct net *net);
1146 void tcp6_proc_exit(struct net *net);
1147 int udp6_proc_init(struct net *net);
1148 void udp6_proc_exit(struct net *net);
1149 int udplite6_proc_init(void);
1150 void udplite6_proc_exit(void);
1151 int ipv6_misc_proc_init(void);
1152 void ipv6_misc_proc_exit(void);
1153 int snmp6_register_dev(struct inet6_dev *idev);
1154 int snmp6_unregister_dev(struct inet6_dev *idev);
1155 
1156 #else
1157 static inline int ac6_proc_init(struct net *net) { return 0; }
1158 static inline void ac6_proc_exit(struct net *net) { }
1159 static inline int snmp6_register_dev(struct inet6_dev *idev) { return 0; }
1160 static inline int snmp6_unregister_dev(struct inet6_dev *idev) { return 0; }
1161 #endif
1162 
1163 #ifdef CONFIG_SYSCTL
1164 struct ctl_table *ipv6_icmp_sysctl_init(struct net *net);
1165 struct ctl_table *ipv6_route_sysctl_init(struct net *net);
1166 int ipv6_sysctl_register(void);
1167 void ipv6_sysctl_unregister(void);
1168 #endif
1169 
1170 int ipv6_sock_mc_join(struct sock *sk, int ifindex,
1171 		      const struct in6_addr *addr);
1172 int ipv6_sock_mc_join_ssm(struct sock *sk, int ifindex,
1173 			  const struct in6_addr *addr, unsigned int mode);
1174 int ipv6_sock_mc_drop(struct sock *sk, int ifindex,
1175 		      const struct in6_addr *addr);
1176 
1177 static inline int ip6_sock_set_v6only(struct sock *sk)
1178 {
1179 	if (inet_sk(sk)->inet_num)
1180 		return -EINVAL;
1181 	lock_sock(sk);
1182 	sk->sk_ipv6only = true;
1183 	release_sock(sk);
1184 	return 0;
1185 }
1186 
1187 static inline void ip6_sock_set_recverr(struct sock *sk)
1188 {
1189 	lock_sock(sk);
1190 	inet6_sk(sk)->recverr = true;
1191 	release_sock(sk);
1192 }
1193 
1194 static inline int __ip6_sock_set_addr_preferences(struct sock *sk, int val)
1195 {
1196 	unsigned int pref = 0;
1197 	unsigned int prefmask = ~0;
1198 
1199 	/* check PUBLIC/TMP/PUBTMP_DEFAULT conflicts */
1200 	switch (val & (IPV6_PREFER_SRC_PUBLIC |
1201 		       IPV6_PREFER_SRC_TMP |
1202 		       IPV6_PREFER_SRC_PUBTMP_DEFAULT)) {
1203 	case IPV6_PREFER_SRC_PUBLIC:
1204 		pref |= IPV6_PREFER_SRC_PUBLIC;
1205 		prefmask &= ~(IPV6_PREFER_SRC_PUBLIC |
1206 			      IPV6_PREFER_SRC_TMP);
1207 		break;
1208 	case IPV6_PREFER_SRC_TMP:
1209 		pref |= IPV6_PREFER_SRC_TMP;
1210 		prefmask &= ~(IPV6_PREFER_SRC_PUBLIC |
1211 			      IPV6_PREFER_SRC_TMP);
1212 		break;
1213 	case IPV6_PREFER_SRC_PUBTMP_DEFAULT:
1214 		prefmask &= ~(IPV6_PREFER_SRC_PUBLIC |
1215 			      IPV6_PREFER_SRC_TMP);
1216 		break;
1217 	case 0:
1218 		break;
1219 	default:
1220 		return -EINVAL;
1221 	}
1222 
1223 	/* check HOME/COA conflicts */
1224 	switch (val & (IPV6_PREFER_SRC_HOME | IPV6_PREFER_SRC_COA)) {
1225 	case IPV6_PREFER_SRC_HOME:
1226 		prefmask &= ~IPV6_PREFER_SRC_COA;
1227 		break;
1228 	case IPV6_PREFER_SRC_COA:
1229 		pref |= IPV6_PREFER_SRC_COA;
1230 		break;
1231 	case 0:
1232 		break;
1233 	default:
1234 		return -EINVAL;
1235 	}
1236 
1237 	/* check CGA/NONCGA conflicts */
1238 	switch (val & (IPV6_PREFER_SRC_CGA|IPV6_PREFER_SRC_NONCGA)) {
1239 	case IPV6_PREFER_SRC_CGA:
1240 	case IPV6_PREFER_SRC_NONCGA:
1241 	case 0:
1242 		break;
1243 	default:
1244 		return -EINVAL;
1245 	}
1246 
1247 	inet6_sk(sk)->srcprefs = (inet6_sk(sk)->srcprefs & prefmask) | pref;
1248 	return 0;
1249 }
1250 
1251 static inline int ip6_sock_set_addr_preferences(struct sock *sk, bool val)
1252 {
1253 	int ret;
1254 
1255 	lock_sock(sk);
1256 	ret = __ip6_sock_set_addr_preferences(sk, val);
1257 	release_sock(sk);
1258 	return ret;
1259 }
1260 
1261 static inline void ip6_sock_set_recvpktinfo(struct sock *sk)
1262 {
1263 	lock_sock(sk);
1264 	inet6_sk(sk)->rxopt.bits.rxinfo = true;
1265 	release_sock(sk);
1266 }
1267 
1268 #endif /* _NET_IPV6_H */
1269