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/flow.h>
19#include <net/flow_dissector.h>
20#include <net/inet_dscp.h>
21#include <net/snmp.h>
22#include <net/netns/hash.h>
23
24struct ip_tunnel_info;
25
26#define SIN6_LEN_RFC2133	24
27
28#define IPV6_MAXPLEN		65535
29
30/*
31 *	NextHeader field of IPv6 header
32 */
33
34#define NEXTHDR_HOP		0	/* Hop-by-hop option header. */
35#define NEXTHDR_IPV4		4	/* IPv4 in IPv6 */
36#define NEXTHDR_TCP		6	/* TCP segment. */
37#define NEXTHDR_UDP		17	/* UDP message. */
38#define NEXTHDR_IPV6		41	/* IPv6 in IPv6 */
39#define NEXTHDR_ROUTING		43	/* Routing header. */
40#define NEXTHDR_FRAGMENT	44	/* Fragmentation/reassembly header. */
41#define NEXTHDR_GRE		47	/* GRE header. */
42#define NEXTHDR_ESP		50	/* Encapsulating security payload. */
43#define NEXTHDR_AUTH		51	/* Authentication header. */
44#define NEXTHDR_ICMP		58	/* ICMP for IPv6. */
45#define NEXTHDR_NONE		59	/* No next header */
46#define NEXTHDR_DEST		60	/* Destination options header. */
47#define NEXTHDR_SCTP		132	/* SCTP message. */
48#define NEXTHDR_MOBILITY	135	/* Mobility header. */
49
50#define NEXTHDR_MAX		255
51
52#define IPV6_DEFAULT_HOPLIMIT   64
53#define IPV6_DEFAULT_MCASTHOPS	1
54
55/* Limits on Hop-by-Hop and Destination options.
56 *
57 * Per RFC8200 there is no limit on the maximum number or lengths of options in
58 * Hop-by-Hop or Destination options other then the packet must fit in an MTU.
59 * We allow configurable limits in order to mitigate potential denial of
60 * service attacks.
61 *
62 * There are three limits that may be set:
63 *   - Limit the number of options in a Hop-by-Hop or Destination options
64 *     extension header
65 *   - Limit the byte length of a Hop-by-Hop or Destination options extension
66 *     header
67 *   - Disallow unknown options
68 *
69 * The limits are expressed in corresponding sysctls:
70 *
71 * ipv6.sysctl.max_dst_opts_cnt
72 * ipv6.sysctl.max_hbh_opts_cnt
73 * ipv6.sysctl.max_dst_opts_len
74 * ipv6.sysctl.max_hbh_opts_len
75 *
76 * max_*_opts_cnt is the number of TLVs that are allowed for Destination
77 * options or Hop-by-Hop options. If the number is less than zero then unknown
78 * TLVs are disallowed and the number of known options that are allowed is the
79 * absolute value. Setting the value to INT_MAX indicates no limit.
80 *
81 * max_*_opts_len is the length limit in bytes of a Destination or
82 * Hop-by-Hop options extension header. Setting the value to INT_MAX
83 * indicates no length limit.
84 *
85 * If a limit is exceeded when processing an extension header the packet is
86 * silently discarded.
87 */
88
89/* Default limits for Hop-by-Hop and Destination options */
90#define IP6_DEFAULT_MAX_DST_OPTS_CNT	 8
91#define IP6_DEFAULT_MAX_HBH_OPTS_CNT	 8
92#define IP6_DEFAULT_MAX_DST_OPTS_LEN	 INT_MAX /* No limit */
93#define IP6_DEFAULT_MAX_HBH_OPTS_LEN	 INT_MAX /* No limit */
94
95/*
96 *	Addr type
97 *
98 *	type	-	unicast | multicast
99 *	scope	-	local	| site	    | global
100 *	v4	-	compat
101 *	v4mapped
102 *	any
103 *	loopback
104 */
105
106#define IPV6_ADDR_ANY		0x0000U
107
108#define IPV6_ADDR_UNICAST	0x0001U
109#define IPV6_ADDR_MULTICAST	0x0002U
110
111#define IPV6_ADDR_LOOPBACK	0x0010U
112#define IPV6_ADDR_LINKLOCAL	0x0020U
113#define IPV6_ADDR_SITELOCAL	0x0040U
114
115#define IPV6_ADDR_COMPATv4	0x0080U
116
117#define IPV6_ADDR_SCOPE_MASK	0x00f0U
118
119#define IPV6_ADDR_MAPPED	0x1000U
120
121/*
122 *	Addr scopes
123 */
124#define IPV6_ADDR_MC_SCOPE(a)	\
125	((a)->s6_addr[1] & 0x0f)	/* nonstandard */
126#define __IPV6_ADDR_SCOPE_INVALID	-1
127#define IPV6_ADDR_SCOPE_NODELOCAL	0x01
128#define IPV6_ADDR_SCOPE_LINKLOCAL	0x02
129#define IPV6_ADDR_SCOPE_SITELOCAL	0x05
130#define IPV6_ADDR_SCOPE_ORGLOCAL	0x08
131#define IPV6_ADDR_SCOPE_GLOBAL		0x0e
132
133/*
134 *	Addr flags
135 */
136#define IPV6_ADDR_MC_FLAG_TRANSIENT(a)	\
137	((a)->s6_addr[1] & 0x10)
138#define IPV6_ADDR_MC_FLAG_PREFIX(a)	\
139	((a)->s6_addr[1] & 0x20)
140#define IPV6_ADDR_MC_FLAG_RENDEZVOUS(a)	\
141	((a)->s6_addr[1] & 0x40)
142
143/*
144 *	fragmentation header
145 */
146
147struct frag_hdr {
148	__u8	nexthdr;
149	__u8	reserved;
150	__be16	frag_off;
151	__be32	identification;
152};
153
154/*
155 * Jumbo payload option, as described in RFC 2675 2.
156 */
157struct hop_jumbo_hdr {
158	u8	nexthdr;
159	u8	hdrlen;
160	u8	tlv_type;	/* IPV6_TLV_JUMBO, 0xC2 */
161	u8	tlv_len;	/* 4 */
162	__be32	jumbo_payload_len;
163};
164
165#define	IP6_MF		0x0001
166#define	IP6_OFFSET	0xFFF8
167
168struct ip6_fraglist_iter {
169	struct ipv6hdr	*tmp_hdr;
170	struct sk_buff	*frag;
171	int		offset;
172	unsigned int	hlen;
173	__be32		frag_id;
174	u8		nexthdr;
175};
176
177int ip6_fraglist_init(struct sk_buff *skb, unsigned int hlen, u8 *prevhdr,
178		      u8 nexthdr, __be32 frag_id,
179		      struct ip6_fraglist_iter *iter);
180void ip6_fraglist_prepare(struct sk_buff *skb, struct ip6_fraglist_iter *iter);
181
182static inline struct sk_buff *ip6_fraglist_next(struct ip6_fraglist_iter *iter)
183{
184	struct sk_buff *skb = iter->frag;
185
186	iter->frag = skb->next;
187	skb_mark_not_on_list(skb);
188
189	return skb;
190}
191
192struct ip6_frag_state {
193	u8		*prevhdr;
194	unsigned int	hlen;
195	unsigned int	mtu;
196	unsigned int	left;
197	int		offset;
198	int		ptr;
199	int		hroom;
200	int		troom;
201	__be32		frag_id;
202	u8		nexthdr;
203};
204
205void ip6_frag_init(struct sk_buff *skb, unsigned int hlen, unsigned int mtu,
206		   unsigned short needed_tailroom, int hdr_room, u8 *prevhdr,
207		   u8 nexthdr, __be32 frag_id, struct ip6_frag_state *state);
208struct sk_buff *ip6_frag_next(struct sk_buff *skb,
209			      struct ip6_frag_state *state);
210
211#define IP6_REPLY_MARK(net, mark) \
212	((net)->ipv6.sysctl.fwmark_reflect ? (mark) : 0)
213
214#include <net/sock.h>
215
216/* sysctls */
217extern int sysctl_mld_max_msf;
218extern int sysctl_mld_qrv;
219
220#define _DEVINC(net, statname, mod, idev, field)			\
221({									\
222	struct inet6_dev *_idev = (idev);				\
223	if (likely(_idev != NULL))					\
224		mod##SNMP_INC_STATS64((_idev)->stats.statname, (field));\
225	mod##SNMP_INC_STATS64((net)->mib.statname##_statistics, (field));\
226})
227
228/* per device counters are atomic_long_t */
229#define _DEVINCATOMIC(net, statname, mod, idev, field)			\
230({									\
231	struct inet6_dev *_idev = (idev);				\
232	if (likely(_idev != NULL))					\
233		SNMP_INC_STATS_ATOMIC_LONG((_idev)->stats.statname##dev, (field)); \
234	mod##SNMP_INC_STATS((net)->mib.statname##_statistics, (field));\
235})
236
237/* per device and per net counters are atomic_long_t */
238#define _DEVINC_ATOMIC_ATOMIC(net, statname, idev, field)		\
239({									\
240	struct inet6_dev *_idev = (idev);				\
241	if (likely(_idev != NULL))					\
242		SNMP_INC_STATS_ATOMIC_LONG((_idev)->stats.statname##dev, (field)); \
243	SNMP_INC_STATS_ATOMIC_LONG((net)->mib.statname##_statistics, (field));\
244})
245
246#define _DEVADD(net, statname, mod, idev, field, val)			\
247({									\
248	struct inet6_dev *_idev = (idev);				\
249	if (likely(_idev != NULL))					\
250		mod##SNMP_ADD_STATS((_idev)->stats.statname, (field), (val)); \
251	mod##SNMP_ADD_STATS((net)->mib.statname##_statistics, (field), (val));\
252})
253
254#define _DEVUPD(net, statname, mod, idev, field, val)			\
255({									\
256	struct inet6_dev *_idev = (idev);				\
257	if (likely(_idev != NULL))					\
258		mod##SNMP_UPD_PO_STATS((_idev)->stats.statname, field, (val)); \
259	mod##SNMP_UPD_PO_STATS((net)->mib.statname##_statistics, field, (val));\
260})
261
262/* MIBs */
263
264#define IP6_INC_STATS(net, idev,field)		\
265		_DEVINC(net, ipv6, , idev, field)
266#define __IP6_INC_STATS(net, idev,field)	\
267		_DEVINC(net, ipv6, __, idev, field)
268#define IP6_ADD_STATS(net, idev,field,val)	\
269		_DEVADD(net, ipv6, , idev, field, val)
270#define __IP6_ADD_STATS(net, idev,field,val)	\
271		_DEVADD(net, ipv6, __, idev, field, val)
272#define IP6_UPD_PO_STATS(net, idev,field,val)   \
273		_DEVUPD(net, ipv6, , idev, field, val)
274#define __IP6_UPD_PO_STATS(net, idev,field,val)   \
275		_DEVUPD(net, ipv6, __, idev, field, val)
276#define ICMP6_INC_STATS(net, idev, field)	\
277		_DEVINCATOMIC(net, icmpv6, , idev, field)
278#define __ICMP6_INC_STATS(net, idev, field)	\
279		_DEVINCATOMIC(net, icmpv6, __, idev, field)
280
281#define ICMP6MSGOUT_INC_STATS(net, idev, field)		\
282	_DEVINC_ATOMIC_ATOMIC(net, icmpv6msg, idev, field +256)
283#define ICMP6MSGIN_INC_STATS(net, idev, field)	\
284	_DEVINC_ATOMIC_ATOMIC(net, icmpv6msg, idev, field)
285
286struct ip6_ra_chain {
287	struct ip6_ra_chain	*next;
288	struct sock		*sk;
289	int			sel;
290	void			(*destructor)(struct sock *);
291};
292
293extern struct ip6_ra_chain	*ip6_ra_chain;
294extern rwlock_t ip6_ra_lock;
295
296/*
297   This structure is prepared by protocol, when parsing
298   ancillary data and passed to IPv6.
299 */
300
301struct ipv6_txoptions {
302	refcount_t		refcnt;
303	/* Length of this structure */
304	int			tot_len;
305
306	/* length of extension headers   */
307
308	__u16			opt_flen;	/* after fragment hdr */
309	__u16			opt_nflen;	/* before fragment hdr */
310
311	struct ipv6_opt_hdr	*hopopt;
312	struct ipv6_opt_hdr	*dst0opt;
313	struct ipv6_rt_hdr	*srcrt;	/* Routing Header */
314	struct ipv6_opt_hdr	*dst1opt;
315	struct rcu_head		rcu;
316	/* Option buffer, as read by IPV6_PKTOPTIONS, starts here. */
317};
318
319/* flowlabel_reflect sysctl values */
320enum flowlabel_reflect {
321	FLOWLABEL_REFLECT_ESTABLISHED		= 1,
322	FLOWLABEL_REFLECT_TCP_RESET		= 2,
323	FLOWLABEL_REFLECT_ICMPV6_ECHO_REPLIES	= 4,
324};
325
326struct ip6_flowlabel {
327	struct ip6_flowlabel __rcu *next;
328	__be32			label;
329	atomic_t		users;
330	struct in6_addr		dst;
331	struct ipv6_txoptions	*opt;
332	unsigned long		linger;
333	struct rcu_head		rcu;
334	u8			share;
335	union {
336		struct pid *pid;
337		kuid_t uid;
338	} owner;
339	unsigned long		lastuse;
340	unsigned long		expires;
341	struct net		*fl_net;
342};
343
344#define IPV6_FLOWINFO_MASK		cpu_to_be32(0x0FFFFFFF)
345#define IPV6_FLOWLABEL_MASK		cpu_to_be32(0x000FFFFF)
346#define IPV6_FLOWLABEL_STATELESS_FLAG	cpu_to_be32(0x00080000)
347
348#define IPV6_TCLASS_MASK (IPV6_FLOWINFO_MASK & ~IPV6_FLOWLABEL_MASK)
349#define IPV6_TCLASS_SHIFT	20
350
351struct ipv6_fl_socklist {
352	struct ipv6_fl_socklist	__rcu	*next;
353	struct ip6_flowlabel		*fl;
354	struct rcu_head			rcu;
355};
356
357struct ipcm6_cookie {
358	struct sockcm_cookie sockc;
359	__s16 hlimit;
360	__s16 tclass;
361	__u16 gso_size;
362	__s8  dontfrag;
363	struct ipv6_txoptions *opt;
364};
365
366static inline void ipcm6_init(struct ipcm6_cookie *ipc6)
367{
368	*ipc6 = (struct ipcm6_cookie) {
369		.hlimit = -1,
370		.tclass = -1,
371		.dontfrag = -1,
372	};
373}
374
375static inline void ipcm6_init_sk(struct ipcm6_cookie *ipc6,
376				 const struct sock *sk)
377{
378	*ipc6 = (struct ipcm6_cookie) {
379		.hlimit = -1,
380		.tclass = inet6_sk(sk)->tclass,
381		.dontfrag = inet6_test_bit(DONTFRAG, sk),
382	};
383}
384
385static inline struct ipv6_txoptions *txopt_get(const struct ipv6_pinfo *np)
386{
387	struct ipv6_txoptions *opt;
388
389	rcu_read_lock();
390	opt = rcu_dereference(np->opt);
391	if (opt) {
392		if (!refcount_inc_not_zero(&opt->refcnt))
393			opt = NULL;
394		else
395			opt = rcu_pointer_handoff(opt);
396	}
397	rcu_read_unlock();
398	return opt;
399}
400
401static inline void txopt_put(struct ipv6_txoptions *opt)
402{
403	if (opt && refcount_dec_and_test(&opt->refcnt))
404		kfree_rcu(opt, rcu);
405}
406
407#if IS_ENABLED(CONFIG_IPV6)
408struct ip6_flowlabel *__fl6_sock_lookup(struct sock *sk, __be32 label);
409
410extern struct static_key_false_deferred ipv6_flowlabel_exclusive;
411static inline struct ip6_flowlabel *fl6_sock_lookup(struct sock *sk,
412						    __be32 label)
413{
414	if (static_branch_unlikely(&ipv6_flowlabel_exclusive.key) &&
415	    READ_ONCE(sock_net(sk)->ipv6.flowlabel_has_excl))
416		return __fl6_sock_lookup(sk, label) ? : ERR_PTR(-ENOENT);
417
418	return NULL;
419}
420#endif
421
422struct ipv6_txoptions *fl6_merge_options(struct ipv6_txoptions *opt_space,
423					 struct ip6_flowlabel *fl,
424					 struct ipv6_txoptions *fopt);
425void fl6_free_socklist(struct sock *sk);
426int ipv6_flowlabel_opt(struct sock *sk, sockptr_t optval, int optlen);
427int ipv6_flowlabel_opt_get(struct sock *sk, struct in6_flowlabel_req *freq,
428			   int flags);
429int ip6_flowlabel_init(void);
430void ip6_flowlabel_cleanup(void);
431bool ip6_autoflowlabel(struct net *net, const struct sock *sk);
432
433static inline void fl6_sock_release(struct ip6_flowlabel *fl)
434{
435	if (fl)
436		atomic_dec(&fl->users);
437}
438
439enum skb_drop_reason icmpv6_notify(struct sk_buff *skb, u8 type,
440				   u8 code, __be32 info);
441
442void icmpv6_push_pending_frames(struct sock *sk, struct flowi6 *fl6,
443				struct icmp6hdr *thdr, int len);
444
445int ip6_ra_control(struct sock *sk, int sel);
446
447int ipv6_parse_hopopts(struct sk_buff *skb);
448
449struct ipv6_txoptions *ipv6_dup_options(struct sock *sk,
450					struct ipv6_txoptions *opt);
451struct ipv6_txoptions *ipv6_renew_options(struct sock *sk,
452					  struct ipv6_txoptions *opt,
453					  int newtype,
454					  struct ipv6_opt_hdr *newopt);
455struct ipv6_txoptions *__ipv6_fixup_options(struct ipv6_txoptions *opt_space,
456					    struct ipv6_txoptions *opt);
457
458static inline struct ipv6_txoptions *
459ipv6_fixup_options(struct ipv6_txoptions *opt_space, struct ipv6_txoptions *opt)
460{
461	if (!opt)
462		return NULL;
463	return __ipv6_fixup_options(opt_space, opt);
464}
465
466bool ipv6_opt_accepted(const struct sock *sk, const struct sk_buff *skb,
467		       const struct inet6_skb_parm *opt);
468struct ipv6_txoptions *ipv6_update_options(struct sock *sk,
469					   struct ipv6_txoptions *opt);
470
471/* This helper is specialized for BIG TCP needs.
472 * It assumes the hop_jumbo_hdr will immediately follow the IPV6 header.
473 * It assumes headers are already in skb->head.
474 * Returns 0, or IPPROTO_TCP if a BIG TCP packet is there.
475 */
476static inline int ipv6_has_hopopt_jumbo(const struct sk_buff *skb)
477{
478	const struct hop_jumbo_hdr *jhdr;
479	const struct ipv6hdr *nhdr;
480
481	if (likely(skb->len <= GRO_LEGACY_MAX_SIZE))
482		return 0;
483
484	if (skb->protocol != htons(ETH_P_IPV6))
485		return 0;
486
487	if (skb_network_offset(skb) +
488	    sizeof(struct ipv6hdr) +
489	    sizeof(struct hop_jumbo_hdr) > skb_headlen(skb))
490		return 0;
491
492	nhdr = ipv6_hdr(skb);
493
494	if (nhdr->nexthdr != NEXTHDR_HOP)
495		return 0;
496
497	jhdr = (const struct hop_jumbo_hdr *) (nhdr + 1);
498	if (jhdr->tlv_type != IPV6_TLV_JUMBO || jhdr->hdrlen != 0 ||
499	    jhdr->nexthdr != IPPROTO_TCP)
500		return 0;
501	return jhdr->nexthdr;
502}
503
504/* Return 0 if HBH header is successfully removed
505 * Or if HBH removal is unnecessary (packet is not big TCP)
506 * Return error to indicate dropping the packet
507 */
508static inline int ipv6_hopopt_jumbo_remove(struct sk_buff *skb)
509{
510	const int hophdr_len = sizeof(struct hop_jumbo_hdr);
511	int nexthdr = ipv6_has_hopopt_jumbo(skb);
512	struct ipv6hdr *h6;
513
514	if (!nexthdr)
515		return 0;
516
517	if (skb_cow_head(skb, 0))
518		return -1;
519
520	/* Remove the HBH header.
521	 * Layout: [Ethernet header][IPv6 header][HBH][L4 Header]
522	 */
523	memmove(skb_mac_header(skb) + hophdr_len, skb_mac_header(skb),
524		skb_network_header(skb) - skb_mac_header(skb) +
525		sizeof(struct ipv6hdr));
526
527	__skb_pull(skb, hophdr_len);
528	skb->network_header += hophdr_len;
529	skb->mac_header += hophdr_len;
530
531	h6 = ipv6_hdr(skb);
532	h6->nexthdr = nexthdr;
533
534	return 0;
535}
536
537static inline bool ipv6_accept_ra(const struct inet6_dev *idev)
538{
539	s32 accept_ra = READ_ONCE(idev->cnf.accept_ra);
540
541	/* If forwarding is enabled, RA are not accepted unless the special
542	 * hybrid mode (accept_ra=2) is enabled.
543	 */
544	return READ_ONCE(idev->cnf.forwarding) ? accept_ra == 2 :
545		accept_ra;
546}
547
548#define IPV6_FRAG_HIGH_THRESH	(4 * 1024*1024)	/* 4194304 */
549#define IPV6_FRAG_LOW_THRESH	(3 * 1024*1024)	/* 3145728 */
550#define IPV6_FRAG_TIMEOUT	(60 * HZ)	/* 60 seconds */
551
552int __ipv6_addr_type(const struct in6_addr *addr);
553static inline int ipv6_addr_type(const struct in6_addr *addr)
554{
555	return __ipv6_addr_type(addr) & 0xffff;
556}
557
558static inline int ipv6_addr_scope(const struct in6_addr *addr)
559{
560	return __ipv6_addr_type(addr) & IPV6_ADDR_SCOPE_MASK;
561}
562
563static inline int __ipv6_addr_src_scope(int type)
564{
565	return (type == IPV6_ADDR_ANY) ? __IPV6_ADDR_SCOPE_INVALID : (type >> 16);
566}
567
568static inline int ipv6_addr_src_scope(const struct in6_addr *addr)
569{
570	return __ipv6_addr_src_scope(__ipv6_addr_type(addr));
571}
572
573static inline bool __ipv6_addr_needs_scope_id(int type)
574{
575	return type & IPV6_ADDR_LINKLOCAL ||
576	       (type & IPV6_ADDR_MULTICAST &&
577		(type & (IPV6_ADDR_LOOPBACK|IPV6_ADDR_LINKLOCAL)));
578}
579
580static inline __u32 ipv6_iface_scope_id(const struct in6_addr *addr, int iface)
581{
582	return __ipv6_addr_needs_scope_id(__ipv6_addr_type(addr)) ? iface : 0;
583}
584
585static inline int ipv6_addr_cmp(const struct in6_addr *a1, const struct in6_addr *a2)
586{
587	return memcmp(a1, a2, sizeof(struct in6_addr));
588}
589
590static inline bool
591ipv6_masked_addr_cmp(const struct in6_addr *a1, const struct in6_addr *m,
592		     const struct in6_addr *a2)
593{
594#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
595	const unsigned long *ul1 = (const unsigned long *)a1;
596	const unsigned long *ulm = (const unsigned long *)m;
597	const unsigned long *ul2 = (const unsigned long *)a2;
598
599	return !!(((ul1[0] ^ ul2[0]) & ulm[0]) |
600		  ((ul1[1] ^ ul2[1]) & ulm[1]));
601#else
602	return !!(((a1->s6_addr32[0] ^ a2->s6_addr32[0]) & m->s6_addr32[0]) |
603		  ((a1->s6_addr32[1] ^ a2->s6_addr32[1]) & m->s6_addr32[1]) |
604		  ((a1->s6_addr32[2] ^ a2->s6_addr32[2]) & m->s6_addr32[2]) |
605		  ((a1->s6_addr32[3] ^ a2->s6_addr32[3]) & m->s6_addr32[3]));
606#endif
607}
608
609static inline void ipv6_addr_prefix(struct in6_addr *pfx,
610				    const struct in6_addr *addr,
611				    int plen)
612{
613	/* caller must guarantee 0 <= plen <= 128 */
614	int o = plen >> 3,
615	    b = plen & 0x7;
616
617	memset(pfx->s6_addr, 0, sizeof(pfx->s6_addr));
618	memcpy(pfx->s6_addr, addr, o);
619	if (b != 0)
620		pfx->s6_addr[o] = addr->s6_addr[o] & (0xff00 >> b);
621}
622
623static inline void ipv6_addr_prefix_copy(struct in6_addr *addr,
624					 const struct in6_addr *pfx,
625					 int plen)
626{
627	/* caller must guarantee 0 <= plen <= 128 */
628	int o = plen >> 3,
629	    b = plen & 0x7;
630
631	memcpy(addr->s6_addr, pfx, o);
632	if (b != 0) {
633		addr->s6_addr[o] &= ~(0xff00 >> b);
634		addr->s6_addr[o] |= (pfx->s6_addr[o] & (0xff00 >> b));
635	}
636}
637
638static inline void __ipv6_addr_set_half(__be32 *addr,
639					__be32 wh, __be32 wl)
640{
641#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
642#if defined(__BIG_ENDIAN)
643	if (__builtin_constant_p(wh) && __builtin_constant_p(wl)) {
644		*(__force u64 *)addr = ((__force u64)(wh) << 32 | (__force u64)(wl));
645		return;
646	}
647#elif defined(__LITTLE_ENDIAN)
648	if (__builtin_constant_p(wl) && __builtin_constant_p(wh)) {
649		*(__force u64 *)addr = ((__force u64)(wl) << 32 | (__force u64)(wh));
650		return;
651	}
652#endif
653#endif
654	addr[0] = wh;
655	addr[1] = wl;
656}
657
658static inline void ipv6_addr_set(struct in6_addr *addr,
659				     __be32 w1, __be32 w2,
660				     __be32 w3, __be32 w4)
661{
662	__ipv6_addr_set_half(&addr->s6_addr32[0], w1, w2);
663	__ipv6_addr_set_half(&addr->s6_addr32[2], w3, w4);
664}
665
666static inline bool ipv6_addr_equal(const struct in6_addr *a1,
667				   const struct in6_addr *a2)
668{
669#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
670	const unsigned long *ul1 = (const unsigned long *)a1;
671	const unsigned long *ul2 = (const unsigned long *)a2;
672
673	return ((ul1[0] ^ ul2[0]) | (ul1[1] ^ ul2[1])) == 0UL;
674#else
675	return ((a1->s6_addr32[0] ^ a2->s6_addr32[0]) |
676		(a1->s6_addr32[1] ^ a2->s6_addr32[1]) |
677		(a1->s6_addr32[2] ^ a2->s6_addr32[2]) |
678		(a1->s6_addr32[3] ^ a2->s6_addr32[3])) == 0;
679#endif
680}
681
682#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
683static inline bool __ipv6_prefix_equal64_half(const __be64 *a1,
684					      const __be64 *a2,
685					      unsigned int len)
686{
687	if (len && ((*a1 ^ *a2) & cpu_to_be64((~0UL) << (64 - len))))
688		return false;
689	return true;
690}
691
692static inline bool ipv6_prefix_equal(const struct in6_addr *addr1,
693				     const struct in6_addr *addr2,
694				     unsigned int prefixlen)
695{
696	const __be64 *a1 = (const __be64 *)addr1;
697	const __be64 *a2 = (const __be64 *)addr2;
698
699	if (prefixlen >= 64) {
700		if (a1[0] ^ a2[0])
701			return false;
702		return __ipv6_prefix_equal64_half(a1 + 1, a2 + 1, prefixlen - 64);
703	}
704	return __ipv6_prefix_equal64_half(a1, a2, prefixlen);
705}
706#else
707static inline bool ipv6_prefix_equal(const struct in6_addr *addr1,
708				     const struct in6_addr *addr2,
709				     unsigned int prefixlen)
710{
711	const __be32 *a1 = addr1->s6_addr32;
712	const __be32 *a2 = addr2->s6_addr32;
713	unsigned int pdw, pbi;
714
715	/* check complete u32 in prefix */
716	pdw = prefixlen >> 5;
717	if (pdw && memcmp(a1, a2, pdw << 2))
718		return false;
719
720	/* check incomplete u32 in prefix */
721	pbi = prefixlen & 0x1f;
722	if (pbi && ((a1[pdw] ^ a2[pdw]) & htonl((0xffffffff) << (32 - pbi))))
723		return false;
724
725	return true;
726}
727#endif
728
729static inline bool ipv6_addr_any(const struct in6_addr *a)
730{
731#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
732	const unsigned long *ul = (const unsigned long *)a;
733
734	return (ul[0] | ul[1]) == 0UL;
735#else
736	return (a->s6_addr32[0] | a->s6_addr32[1] |
737		a->s6_addr32[2] | a->s6_addr32[3]) == 0;
738#endif
739}
740
741static inline u32 ipv6_addr_hash(const struct in6_addr *a)
742{
743#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
744	const unsigned long *ul = (const unsigned long *)a;
745	unsigned long x = ul[0] ^ ul[1];
746
747	return (u32)(x ^ (x >> 32));
748#else
749	return (__force u32)(a->s6_addr32[0] ^ a->s6_addr32[1] ^
750			     a->s6_addr32[2] ^ a->s6_addr32[3]);
751#endif
752}
753
754/* more secured version of ipv6_addr_hash() */
755static inline u32 __ipv6_addr_jhash(const struct in6_addr *a, const u32 initval)
756{
757	return jhash2((__force const u32 *)a->s6_addr32,
758		      ARRAY_SIZE(a->s6_addr32), initval);
759}
760
761static inline bool ipv6_addr_loopback(const struct in6_addr *a)
762{
763#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
764	const __be64 *be = (const __be64 *)a;
765
766	return (be[0] | (be[1] ^ cpu_to_be64(1))) == 0UL;
767#else
768	return (a->s6_addr32[0] | a->s6_addr32[1] |
769		a->s6_addr32[2] | (a->s6_addr32[3] ^ cpu_to_be32(1))) == 0;
770#endif
771}
772
773/*
774 * Note that we must __force cast these to unsigned long to make sparse happy,
775 * since all of the endian-annotated types are fixed size regardless of arch.
776 */
777static inline bool ipv6_addr_v4mapped(const struct in6_addr *a)
778{
779	return (
780#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
781		*(unsigned long *)a |
782#else
783		(__force unsigned long)(a->s6_addr32[0] | a->s6_addr32[1]) |
784#endif
785		(__force unsigned long)(a->s6_addr32[2] ^
786					cpu_to_be32(0x0000ffff))) == 0UL;
787}
788
789static inline bool ipv6_addr_v4mapped_loopback(const struct in6_addr *a)
790{
791	return ipv6_addr_v4mapped(a) && ipv4_is_loopback(a->s6_addr32[3]);
792}
793
794static inline u32 ipv6_portaddr_hash(const struct net *net,
795				     const struct in6_addr *addr6,
796				     unsigned int port)
797{
798	unsigned int hash, mix = net_hash_mix(net);
799
800	if (ipv6_addr_any(addr6))
801		hash = jhash_1word(0, mix);
802	else if (ipv6_addr_v4mapped(addr6))
803		hash = jhash_1word((__force u32)addr6->s6_addr32[3], mix);
804	else
805		hash = jhash2((__force u32 *)addr6->s6_addr32, 4, mix);
806
807	return hash ^ port;
808}
809
810/*
811 * Check for a RFC 4843 ORCHID address
812 * (Overlay Routable Cryptographic Hash Identifiers)
813 */
814static inline bool ipv6_addr_orchid(const struct in6_addr *a)
815{
816	return (a->s6_addr32[0] & htonl(0xfffffff0)) == htonl(0x20010010);
817}
818
819static inline bool ipv6_addr_is_multicast(const struct in6_addr *addr)
820{
821	return (addr->s6_addr32[0] & htonl(0xFF000000)) == htonl(0xFF000000);
822}
823
824static inline void ipv6_addr_set_v4mapped(const __be32 addr,
825					  struct in6_addr *v4mapped)
826{
827	ipv6_addr_set(v4mapped,
828			0, 0,
829			htonl(0x0000FFFF),
830			addr);
831}
832
833/*
834 * find the first different bit between two addresses
835 * length of address must be a multiple of 32bits
836 */
837static inline int __ipv6_addr_diff32(const void *token1, const void *token2, int addrlen)
838{
839	const __be32 *a1 = token1, *a2 = token2;
840	int i;
841
842	addrlen >>= 2;
843
844	for (i = 0; i < addrlen; i++) {
845		__be32 xb = a1[i] ^ a2[i];
846		if (xb)
847			return i * 32 + 31 - __fls(ntohl(xb));
848	}
849
850	/*
851	 *	we should *never* get to this point since that
852	 *	would mean the addrs are equal
853	 *
854	 *	However, we do get to it 8) And exacly, when
855	 *	addresses are equal 8)
856	 *
857	 *	ip route add 1111::/128 via ...
858	 *	ip route add 1111::/64 via ...
859	 *	and we are here.
860	 *
861	 *	Ideally, this function should stop comparison
862	 *	at prefix length. It does not, but it is still OK,
863	 *	if returned value is greater than prefix length.
864	 *					--ANK (980803)
865	 */
866	return addrlen << 5;
867}
868
869#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
870static inline int __ipv6_addr_diff64(const void *token1, const void *token2, int addrlen)
871{
872	const __be64 *a1 = token1, *a2 = token2;
873	int i;
874
875	addrlen >>= 3;
876
877	for (i = 0; i < addrlen; i++) {
878		__be64 xb = a1[i] ^ a2[i];
879		if (xb)
880			return i * 64 + 63 - __fls(be64_to_cpu(xb));
881	}
882
883	return addrlen << 6;
884}
885#endif
886
887static inline int __ipv6_addr_diff(const void *token1, const void *token2, int addrlen)
888{
889#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
890	if (__builtin_constant_p(addrlen) && !(addrlen & 7))
891		return __ipv6_addr_diff64(token1, token2, addrlen);
892#endif
893	return __ipv6_addr_diff32(token1, token2, addrlen);
894}
895
896static inline int ipv6_addr_diff(const struct in6_addr *a1, const struct in6_addr *a2)
897{
898	return __ipv6_addr_diff(a1, a2, sizeof(struct in6_addr));
899}
900
901__be32 ipv6_select_ident(struct net *net,
902			 const struct in6_addr *daddr,
903			 const struct in6_addr *saddr);
904__be32 ipv6_proxy_select_ident(struct net *net, struct sk_buff *skb);
905
906int ip6_dst_hoplimit(struct dst_entry *dst);
907
908static inline int ip6_sk_dst_hoplimit(struct ipv6_pinfo *np, struct flowi6 *fl6,
909				      struct dst_entry *dst)
910{
911	int hlimit;
912
913	if (ipv6_addr_is_multicast(&fl6->daddr))
914		hlimit = READ_ONCE(np->mcast_hops);
915	else
916		hlimit = READ_ONCE(np->hop_limit);
917	if (hlimit < 0)
918		hlimit = ip6_dst_hoplimit(dst);
919	return hlimit;
920}
921
922/* copy IPv6 saddr & daddr to flow_keys, possibly using 64bit load/store
923 * Equivalent to :	flow->v6addrs.src = iph->saddr;
924 *			flow->v6addrs.dst = iph->daddr;
925 */
926static inline void iph_to_flow_copy_v6addrs(struct flow_keys *flow,
927					    const struct ipv6hdr *iph)
928{
929	BUILD_BUG_ON(offsetof(typeof(flow->addrs), v6addrs.dst) !=
930		     offsetof(typeof(flow->addrs), v6addrs.src) +
931		     sizeof(flow->addrs.v6addrs.src));
932	memcpy(&flow->addrs.v6addrs, &iph->addrs, sizeof(flow->addrs.v6addrs));
933	flow->control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
934}
935
936#if IS_ENABLED(CONFIG_IPV6)
937
938static inline bool ipv6_can_nonlocal_bind(struct net *net,
939					  struct inet_sock *inet)
940{
941	return net->ipv6.sysctl.ip_nonlocal_bind ||
942		test_bit(INET_FLAGS_FREEBIND, &inet->inet_flags) ||
943		test_bit(INET_FLAGS_TRANSPARENT, &inet->inet_flags);
944}
945
946/* Sysctl settings for net ipv6.auto_flowlabels */
947#define IP6_AUTO_FLOW_LABEL_OFF		0
948#define IP6_AUTO_FLOW_LABEL_OPTOUT	1
949#define IP6_AUTO_FLOW_LABEL_OPTIN	2
950#define IP6_AUTO_FLOW_LABEL_FORCED	3
951
952#define IP6_AUTO_FLOW_LABEL_MAX		IP6_AUTO_FLOW_LABEL_FORCED
953
954#define IP6_DEFAULT_AUTO_FLOW_LABELS	IP6_AUTO_FLOW_LABEL_OPTOUT
955
956static inline __be32 ip6_make_flowlabel(struct net *net, struct sk_buff *skb,
957					__be32 flowlabel, bool autolabel,
958					struct flowi6 *fl6)
959{
960	u32 hash;
961
962	/* @flowlabel may include more than a flow label, eg, the traffic class.
963	 * Here we want only the flow label value.
964	 */
965	flowlabel &= IPV6_FLOWLABEL_MASK;
966
967	if (flowlabel ||
968	    net->ipv6.sysctl.auto_flowlabels == IP6_AUTO_FLOW_LABEL_OFF ||
969	    (!autolabel &&
970	     net->ipv6.sysctl.auto_flowlabels != IP6_AUTO_FLOW_LABEL_FORCED))
971		return flowlabel;
972
973	hash = skb_get_hash_flowi6(skb, fl6);
974
975	/* Since this is being sent on the wire obfuscate hash a bit
976	 * to minimize possbility that any useful information to an
977	 * attacker is leaked. Only lower 20 bits are relevant.
978	 */
979	hash = rol32(hash, 16);
980
981	flowlabel = (__force __be32)hash & IPV6_FLOWLABEL_MASK;
982
983	if (net->ipv6.sysctl.flowlabel_state_ranges)
984		flowlabel |= IPV6_FLOWLABEL_STATELESS_FLAG;
985
986	return flowlabel;
987}
988
989static inline int ip6_default_np_autolabel(struct net *net)
990{
991	switch (net->ipv6.sysctl.auto_flowlabels) {
992	case IP6_AUTO_FLOW_LABEL_OFF:
993	case IP6_AUTO_FLOW_LABEL_OPTIN:
994	default:
995		return 0;
996	case IP6_AUTO_FLOW_LABEL_OPTOUT:
997	case IP6_AUTO_FLOW_LABEL_FORCED:
998		return 1;
999	}
1000}
1001#else
1002static inline __be32 ip6_make_flowlabel(struct net *net, struct sk_buff *skb,
1003					__be32 flowlabel, bool autolabel,
1004					struct flowi6 *fl6)
1005{
1006	return flowlabel;
1007}
1008static inline int ip6_default_np_autolabel(struct net *net)
1009{
1010	return 0;
1011}
1012#endif
1013
1014#if IS_ENABLED(CONFIG_IPV6)
1015static inline int ip6_multipath_hash_policy(const struct net *net)
1016{
1017	return net->ipv6.sysctl.multipath_hash_policy;
1018}
1019static inline u32 ip6_multipath_hash_fields(const struct net *net)
1020{
1021	return net->ipv6.sysctl.multipath_hash_fields;
1022}
1023#else
1024static inline int ip6_multipath_hash_policy(const struct net *net)
1025{
1026	return 0;
1027}
1028static inline u32 ip6_multipath_hash_fields(const struct net *net)
1029{
1030	return 0;
1031}
1032#endif
1033
1034/*
1035 *	Header manipulation
1036 */
1037static inline void ip6_flow_hdr(struct ipv6hdr *hdr, unsigned int tclass,
1038				__be32 flowlabel)
1039{
1040	*(__be32 *)hdr = htonl(0x60000000 | (tclass << 20)) | flowlabel;
1041}
1042
1043static inline __be32 ip6_flowinfo(const struct ipv6hdr *hdr)
1044{
1045	return *(__be32 *)hdr & IPV6_FLOWINFO_MASK;
1046}
1047
1048static inline __be32 ip6_flowlabel(const struct ipv6hdr *hdr)
1049{
1050	return *(__be32 *)hdr & IPV6_FLOWLABEL_MASK;
1051}
1052
1053static inline u8 ip6_tclass(__be32 flowinfo)
1054{
1055	return ntohl(flowinfo & IPV6_TCLASS_MASK) >> IPV6_TCLASS_SHIFT;
1056}
1057
1058static inline dscp_t ip6_dscp(__be32 flowinfo)
1059{
1060	return inet_dsfield_to_dscp(ip6_tclass(flowinfo));
1061}
1062
1063static inline __be32 ip6_make_flowinfo(unsigned int tclass, __be32 flowlabel)
1064{
1065	return htonl(tclass << IPV6_TCLASS_SHIFT) | flowlabel;
1066}
1067
1068static inline __be32 flowi6_get_flowlabel(const struct flowi6 *fl6)
1069{
1070	return fl6->flowlabel & IPV6_FLOWLABEL_MASK;
1071}
1072
1073/*
1074 *	Prototypes exported by ipv6
1075 */
1076
1077/*
1078 *	rcv function (called from netdevice level)
1079 */
1080
1081int ipv6_rcv(struct sk_buff *skb, struct net_device *dev,
1082	     struct packet_type *pt, struct net_device *orig_dev);
1083void ipv6_list_rcv(struct list_head *head, struct packet_type *pt,
1084		   struct net_device *orig_dev);
1085
1086int ip6_rcv_finish(struct net *net, struct sock *sk, struct sk_buff *skb);
1087
1088/*
1089 *	upper-layer output functions
1090 */
1091int ip6_xmit(const struct sock *sk, struct sk_buff *skb, struct flowi6 *fl6,
1092	     __u32 mark, struct ipv6_txoptions *opt, int tclass, u32 priority);
1093
1094int ip6_find_1stfragopt(struct sk_buff *skb, u8 **nexthdr);
1095
1096int ip6_append_data(struct sock *sk,
1097		    int getfrag(void *from, char *to, int offset, int len,
1098				int odd, struct sk_buff *skb),
1099		    void *from, size_t length, int transhdrlen,
1100		    struct ipcm6_cookie *ipc6, struct flowi6 *fl6,
1101		    struct rt6_info *rt, unsigned int flags);
1102
1103int ip6_push_pending_frames(struct sock *sk);
1104
1105void ip6_flush_pending_frames(struct sock *sk);
1106
1107int ip6_send_skb(struct sk_buff *skb);
1108
1109struct sk_buff *__ip6_make_skb(struct sock *sk, struct sk_buff_head *queue,
1110			       struct inet_cork_full *cork,
1111			       struct inet6_cork *v6_cork);
1112struct sk_buff *ip6_make_skb(struct sock *sk,
1113			     int getfrag(void *from, char *to, int offset,
1114					 int len, int odd, struct sk_buff *skb),
1115			     void *from, size_t length, int transhdrlen,
1116			     struct ipcm6_cookie *ipc6,
1117			     struct rt6_info *rt, unsigned int flags,
1118			     struct inet_cork_full *cork);
1119
1120static inline struct sk_buff *ip6_finish_skb(struct sock *sk)
1121{
1122	return __ip6_make_skb(sk, &sk->sk_write_queue, &inet_sk(sk)->cork,
1123			      &inet6_sk(sk)->cork);
1124}
1125
1126int ip6_dst_lookup(struct net *net, struct sock *sk, struct dst_entry **dst,
1127		   struct flowi6 *fl6);
1128struct dst_entry *ip6_dst_lookup_flow(struct net *net, const struct sock *sk, struct flowi6 *fl6,
1129				      const struct in6_addr *final_dst);
1130struct dst_entry *ip6_sk_dst_lookup_flow(struct sock *sk, struct flowi6 *fl6,
1131					 const struct in6_addr *final_dst,
1132					 bool connected);
1133struct dst_entry *ip6_blackhole_route(struct net *net,
1134				      struct dst_entry *orig_dst);
1135
1136/*
1137 *	skb processing functions
1138 */
1139
1140int ip6_output(struct net *net, struct sock *sk, struct sk_buff *skb);
1141int ip6_forward(struct sk_buff *skb);
1142int ip6_input(struct sk_buff *skb);
1143int ip6_mc_input(struct sk_buff *skb);
1144void ip6_protocol_deliver_rcu(struct net *net, struct sk_buff *skb, int nexthdr,
1145			      bool have_final);
1146
1147int __ip6_local_out(struct net *net, struct sock *sk, struct sk_buff *skb);
1148int ip6_local_out(struct net *net, struct sock *sk, struct sk_buff *skb);
1149
1150/*
1151 *	Extension header (options) processing
1152 */
1153
1154void ipv6_push_nfrag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt,
1155			  u8 *proto, struct in6_addr **daddr_p,
1156			  struct in6_addr *saddr);
1157void ipv6_push_frag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt,
1158			 u8 *proto);
1159
1160int ipv6_skip_exthdr(const struct sk_buff *, int start, u8 *nexthdrp,
1161		     __be16 *frag_offp);
1162
1163bool ipv6_ext_hdr(u8 nexthdr);
1164
1165enum {
1166	IP6_FH_F_FRAG		= (1 << 0),
1167	IP6_FH_F_AUTH		= (1 << 1),
1168	IP6_FH_F_SKIP_RH	= (1 << 2),
1169};
1170
1171/* find specified header and get offset to it */
1172int ipv6_find_hdr(const struct sk_buff *skb, unsigned int *offset, int target,
1173		  unsigned short *fragoff, int *fragflg);
1174
1175int ipv6_find_tlv(const struct sk_buff *skb, int offset, int type);
1176
1177struct in6_addr *fl6_update_dst(struct flowi6 *fl6,
1178				const struct ipv6_txoptions *opt,
1179				struct in6_addr *orig);
1180
1181/*
1182 *	socket options (ipv6_sockglue.c)
1183 */
1184DECLARE_STATIC_KEY_FALSE(ip6_min_hopcount);
1185
1186int do_ipv6_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval,
1187		       unsigned int optlen);
1188int ipv6_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval,
1189		    unsigned int optlen);
1190int do_ipv6_getsockopt(struct sock *sk, int level, int optname,
1191		       sockptr_t optval, sockptr_t optlen);
1192int ipv6_getsockopt(struct sock *sk, int level, int optname,
1193		    char __user *optval, int __user *optlen);
1194
1195int __ip6_datagram_connect(struct sock *sk, struct sockaddr *addr,
1196			   int addr_len);
1197int ip6_datagram_connect(struct sock *sk, struct sockaddr *addr, int addr_len);
1198int ip6_datagram_connect_v6_only(struct sock *sk, struct sockaddr *addr,
1199				 int addr_len);
1200int ip6_datagram_dst_update(struct sock *sk, bool fix_sk_saddr);
1201void ip6_datagram_release_cb(struct sock *sk);
1202
1203int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len,
1204		    int *addr_len);
1205int ipv6_recv_rxpmtu(struct sock *sk, struct msghdr *msg, int len,
1206		     int *addr_len);
1207void ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err, __be16 port,
1208		     u32 info, u8 *payload);
1209void ipv6_local_error(struct sock *sk, int err, struct flowi6 *fl6, u32 info);
1210void ipv6_local_rxpmtu(struct sock *sk, struct flowi6 *fl6, u32 mtu);
1211
1212void inet6_cleanup_sock(struct sock *sk);
1213void inet6_sock_destruct(struct sock *sk);
1214int inet6_release(struct socket *sock);
1215int inet6_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len);
1216int inet6_bind_sk(struct sock *sk, struct sockaddr *uaddr, int addr_len);
1217int inet6_getname(struct socket *sock, struct sockaddr *uaddr,
1218		  int peer);
1219int inet6_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg);
1220int inet6_compat_ioctl(struct socket *sock, unsigned int cmd,
1221		unsigned long arg);
1222
1223int inet6_hash_connect(struct inet_timewait_death_row *death_row,
1224			      struct sock *sk);
1225int inet6_sendmsg(struct socket *sock, struct msghdr *msg, size_t size);
1226int inet6_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
1227		  int flags);
1228
1229/*
1230 * reassembly.c
1231 */
1232extern const struct proto_ops inet6_stream_ops;
1233extern const struct proto_ops inet6_dgram_ops;
1234extern const struct proto_ops inet6_sockraw_ops;
1235
1236struct group_source_req;
1237struct group_filter;
1238
1239int ip6_mc_source(int add, int omode, struct sock *sk,
1240		  struct group_source_req *pgsr);
1241int ip6_mc_msfilter(struct sock *sk, struct group_filter *gsf,
1242		  struct sockaddr_storage *list);
1243int ip6_mc_msfget(struct sock *sk, struct group_filter *gsf,
1244		  sockptr_t optval, size_t ss_offset);
1245
1246#ifdef CONFIG_PROC_FS
1247int ac6_proc_init(struct net *net);
1248void ac6_proc_exit(struct net *net);
1249int raw6_proc_init(void);
1250void raw6_proc_exit(void);
1251int tcp6_proc_init(struct net *net);
1252void tcp6_proc_exit(struct net *net);
1253int udp6_proc_init(struct net *net);
1254void udp6_proc_exit(struct net *net);
1255int udplite6_proc_init(void);
1256void udplite6_proc_exit(void);
1257int ipv6_misc_proc_init(void);
1258void ipv6_misc_proc_exit(void);
1259int snmp6_register_dev(struct inet6_dev *idev);
1260int snmp6_unregister_dev(struct inet6_dev *idev);
1261
1262#else
1263static inline int ac6_proc_init(struct net *net) { return 0; }
1264static inline void ac6_proc_exit(struct net *net) { }
1265static inline int snmp6_register_dev(struct inet6_dev *idev) { return 0; }
1266static inline int snmp6_unregister_dev(struct inet6_dev *idev) { return 0; }
1267#endif
1268
1269#ifdef CONFIG_SYSCTL
1270struct ctl_table *ipv6_icmp_sysctl_init(struct net *net);
1271size_t ipv6_icmp_sysctl_table_size(void);
1272struct ctl_table *ipv6_route_sysctl_init(struct net *net);
1273size_t ipv6_route_sysctl_table_size(struct net *net);
1274int ipv6_sysctl_register(void);
1275void ipv6_sysctl_unregister(void);
1276#endif
1277
1278int ipv6_sock_mc_join(struct sock *sk, int ifindex,
1279		      const struct in6_addr *addr);
1280int ipv6_sock_mc_join_ssm(struct sock *sk, int ifindex,
1281			  const struct in6_addr *addr, unsigned int mode);
1282int ipv6_sock_mc_drop(struct sock *sk, int ifindex,
1283		      const struct in6_addr *addr);
1284
1285static inline int ip6_sock_set_v6only(struct sock *sk)
1286{
1287	if (inet_sk(sk)->inet_num)
1288		return -EINVAL;
1289	lock_sock(sk);
1290	sk->sk_ipv6only = true;
1291	release_sock(sk);
1292	return 0;
1293}
1294
1295static inline void ip6_sock_set_recverr(struct sock *sk)
1296{
1297	inet6_set_bit(RECVERR6, sk);
1298}
1299
1300#define IPV6_PREFER_SRC_MASK (IPV6_PREFER_SRC_TMP | IPV6_PREFER_SRC_PUBLIC | \
1301			      IPV6_PREFER_SRC_COA)
1302
1303static inline int ip6_sock_set_addr_preferences(struct sock *sk, int val)
1304{
1305	unsigned int prefmask = ~IPV6_PREFER_SRC_MASK;
1306	unsigned int pref = 0;
1307
1308	/* check PUBLIC/TMP/PUBTMP_DEFAULT conflicts */
1309	switch (val & (IPV6_PREFER_SRC_PUBLIC |
1310		       IPV6_PREFER_SRC_TMP |
1311		       IPV6_PREFER_SRC_PUBTMP_DEFAULT)) {
1312	case IPV6_PREFER_SRC_PUBLIC:
1313		pref |= IPV6_PREFER_SRC_PUBLIC;
1314		prefmask &= ~(IPV6_PREFER_SRC_PUBLIC |
1315			      IPV6_PREFER_SRC_TMP);
1316		break;
1317	case IPV6_PREFER_SRC_TMP:
1318		pref |= IPV6_PREFER_SRC_TMP;
1319		prefmask &= ~(IPV6_PREFER_SRC_PUBLIC |
1320			      IPV6_PREFER_SRC_TMP);
1321		break;
1322	case IPV6_PREFER_SRC_PUBTMP_DEFAULT:
1323		prefmask &= ~(IPV6_PREFER_SRC_PUBLIC |
1324			      IPV6_PREFER_SRC_TMP);
1325		break;
1326	case 0:
1327		break;
1328	default:
1329		return -EINVAL;
1330	}
1331
1332	/* check HOME/COA conflicts */
1333	switch (val & (IPV6_PREFER_SRC_HOME | IPV6_PREFER_SRC_COA)) {
1334	case IPV6_PREFER_SRC_HOME:
1335		prefmask &= ~IPV6_PREFER_SRC_COA;
1336		break;
1337	case IPV6_PREFER_SRC_COA:
1338		pref |= IPV6_PREFER_SRC_COA;
1339		break;
1340	case 0:
1341		break;
1342	default:
1343		return -EINVAL;
1344	}
1345
1346	/* check CGA/NONCGA conflicts */
1347	switch (val & (IPV6_PREFER_SRC_CGA|IPV6_PREFER_SRC_NONCGA)) {
1348	case IPV6_PREFER_SRC_CGA:
1349	case IPV6_PREFER_SRC_NONCGA:
1350	case 0:
1351		break;
1352	default:
1353		return -EINVAL;
1354	}
1355
1356	WRITE_ONCE(inet6_sk(sk)->srcprefs,
1357		   (READ_ONCE(inet6_sk(sk)->srcprefs) & prefmask) | pref);
1358	return 0;
1359}
1360
1361static inline void ip6_sock_set_recvpktinfo(struct sock *sk)
1362{
1363	lock_sock(sk);
1364	inet6_sk(sk)->rxopt.bits.rxinfo = true;
1365	release_sock(sk);
1366}
1367
1368#endif /* _NET_IPV6_H */
1369