xref: /linux/include/net/ipv6.h (revision e9adcfecf572fcfaa9f8525904cf49c709974f73)
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 
24 struct 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 
147 struct 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  */
157 struct 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 
168 struct 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 
177 int ip6_fraglist_init(struct sk_buff *skb, unsigned int hlen, u8 *prevhdr,
178 		      u8 nexthdr, __be32 frag_id,
179 		      struct ip6_fraglist_iter *iter);
180 void ip6_fraglist_prepare(struct sk_buff *skb, struct ip6_fraglist_iter *iter);
181 
182 static 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 
192 struct 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 
205 void 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);
208 struct 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 */
217 extern int sysctl_mld_max_msf;
218 extern 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 
286 struct ip6_ra_chain {
287 	struct ip6_ra_chain	*next;
288 	struct sock		*sk;
289 	int			sel;
290 	void			(*destructor)(struct sock *);
291 };
292 
293 extern struct ip6_ra_chain	*ip6_ra_chain;
294 extern 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 
301 struct 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 */
320 enum flowlabel_reflect {
321 	FLOWLABEL_REFLECT_ESTABLISHED		= 1,
322 	FLOWLABEL_REFLECT_TCP_RESET		= 2,
323 	FLOWLABEL_REFLECT_ICMPV6_ECHO_REPLIES	= 4,
324 };
325 
326 struct 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 
351 struct ipv6_fl_socklist {
352 	struct ipv6_fl_socklist	__rcu	*next;
353 	struct ip6_flowlabel		*fl;
354 	struct rcu_head			rcu;
355 };
356 
357 struct 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 
366 static 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 
375 static inline void ipcm6_init_sk(struct ipcm6_cookie *ipc6,
376 				 const struct ipv6_pinfo *np)
377 {
378 	*ipc6 = (struct ipcm6_cookie) {
379 		.hlimit = -1,
380 		.tclass = np->tclass,
381 		.dontfrag = np->dontfrag,
382 	};
383 }
384 
385 static 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 
401 static 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)
408 struct ip6_flowlabel *__fl6_sock_lookup(struct sock *sk, __be32 label);
409 
410 extern struct static_key_false_deferred ipv6_flowlabel_exclusive;
411 static 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 
422 struct ipv6_txoptions *fl6_merge_options(struct ipv6_txoptions *opt_space,
423 					 struct ip6_flowlabel *fl,
424 					 struct ipv6_txoptions *fopt);
425 void fl6_free_socklist(struct sock *sk);
426 int ipv6_flowlabel_opt(struct sock *sk, sockptr_t optval, int optlen);
427 int ipv6_flowlabel_opt_get(struct sock *sk, struct in6_flowlabel_req *freq,
428 			   int flags);
429 int ip6_flowlabel_init(void);
430 void ip6_flowlabel_cleanup(void);
431 bool ip6_autoflowlabel(struct net *net, const struct ipv6_pinfo *np);
432 
433 static inline void fl6_sock_release(struct ip6_flowlabel *fl)
434 {
435 	if (fl)
436 		atomic_dec(&fl->users);
437 }
438 
439 void icmpv6_notify(struct sk_buff *skb, u8 type, u8 code, __be32 info);
440 
441 void icmpv6_push_pending_frames(struct sock *sk, struct flowi6 *fl6,
442 				struct icmp6hdr *thdr, int len);
443 
444 int ip6_ra_control(struct sock *sk, int sel);
445 
446 int ipv6_parse_hopopts(struct sk_buff *skb);
447 
448 struct ipv6_txoptions *ipv6_dup_options(struct sock *sk,
449 					struct ipv6_txoptions *opt);
450 struct ipv6_txoptions *ipv6_renew_options(struct sock *sk,
451 					  struct ipv6_txoptions *opt,
452 					  int newtype,
453 					  struct ipv6_opt_hdr *newopt);
454 struct ipv6_txoptions *__ipv6_fixup_options(struct ipv6_txoptions *opt_space,
455 					    struct ipv6_txoptions *opt);
456 
457 static inline struct ipv6_txoptions *
458 ipv6_fixup_options(struct ipv6_txoptions *opt_space, struct ipv6_txoptions *opt)
459 {
460 	if (!opt)
461 		return NULL;
462 	return __ipv6_fixup_options(opt_space, opt);
463 }
464 
465 bool ipv6_opt_accepted(const struct sock *sk, const struct sk_buff *skb,
466 		       const struct inet6_skb_parm *opt);
467 struct ipv6_txoptions *ipv6_update_options(struct sock *sk,
468 					   struct ipv6_txoptions *opt);
469 
470 /* This helper is specialized for BIG TCP needs.
471  * It assumes the hop_jumbo_hdr will immediately follow the IPV6 header.
472  * It assumes headers are already in skb->head.
473  * Returns 0, or IPPROTO_TCP if a BIG TCP packet is there.
474  */
475 static inline int ipv6_has_hopopt_jumbo(const struct sk_buff *skb)
476 {
477 	const struct hop_jumbo_hdr *jhdr;
478 	const struct ipv6hdr *nhdr;
479 
480 	if (likely(skb->len <= GRO_LEGACY_MAX_SIZE))
481 		return 0;
482 
483 	if (skb->protocol != htons(ETH_P_IPV6))
484 		return 0;
485 
486 	if (skb_network_offset(skb) +
487 	    sizeof(struct ipv6hdr) +
488 	    sizeof(struct hop_jumbo_hdr) > skb_headlen(skb))
489 		return 0;
490 
491 	nhdr = ipv6_hdr(skb);
492 
493 	if (nhdr->nexthdr != NEXTHDR_HOP)
494 		return 0;
495 
496 	jhdr = (const struct hop_jumbo_hdr *) (nhdr + 1);
497 	if (jhdr->tlv_type != IPV6_TLV_JUMBO || jhdr->hdrlen != 0 ||
498 	    jhdr->nexthdr != IPPROTO_TCP)
499 		return 0;
500 	return jhdr->nexthdr;
501 }
502 
503 /* Return 0 if HBH header is successfully removed
504  * Or if HBH removal is unnecessary (packet is not big TCP)
505  * Return error to indicate dropping the packet
506  */
507 static inline int ipv6_hopopt_jumbo_remove(struct sk_buff *skb)
508 {
509 	const int hophdr_len = sizeof(struct hop_jumbo_hdr);
510 	int nexthdr = ipv6_has_hopopt_jumbo(skb);
511 	struct ipv6hdr *h6;
512 
513 	if (!nexthdr)
514 		return 0;
515 
516 	if (skb_cow_head(skb, 0))
517 		return -1;
518 
519 	/* Remove the HBH header.
520 	 * Layout: [Ethernet header][IPv6 header][HBH][L4 Header]
521 	 */
522 	memmove(skb_mac_header(skb) + hophdr_len, skb_mac_header(skb),
523 		skb_network_header(skb) - skb_mac_header(skb) +
524 		sizeof(struct ipv6hdr));
525 
526 	__skb_pull(skb, hophdr_len);
527 	skb->network_header += hophdr_len;
528 	skb->mac_header += hophdr_len;
529 
530 	h6 = ipv6_hdr(skb);
531 	h6->nexthdr = nexthdr;
532 
533 	return 0;
534 }
535 
536 static inline bool ipv6_accept_ra(struct inet6_dev *idev)
537 {
538 	/* If forwarding is enabled, RA are not accepted unless the special
539 	 * hybrid mode (accept_ra=2) is enabled.
540 	 */
541 	return idev->cnf.forwarding ? idev->cnf.accept_ra == 2 :
542 	    idev->cnf.accept_ra;
543 }
544 
545 #define IPV6_FRAG_HIGH_THRESH	(4 * 1024*1024)	/* 4194304 */
546 #define IPV6_FRAG_LOW_THRESH	(3 * 1024*1024)	/* 3145728 */
547 #define IPV6_FRAG_TIMEOUT	(60 * HZ)	/* 60 seconds */
548 
549 int __ipv6_addr_type(const struct in6_addr *addr);
550 static inline int ipv6_addr_type(const struct in6_addr *addr)
551 {
552 	return __ipv6_addr_type(addr) & 0xffff;
553 }
554 
555 static inline int ipv6_addr_scope(const struct in6_addr *addr)
556 {
557 	return __ipv6_addr_type(addr) & IPV6_ADDR_SCOPE_MASK;
558 }
559 
560 static inline int __ipv6_addr_src_scope(int type)
561 {
562 	return (type == IPV6_ADDR_ANY) ? __IPV6_ADDR_SCOPE_INVALID : (type >> 16);
563 }
564 
565 static inline int ipv6_addr_src_scope(const struct in6_addr *addr)
566 {
567 	return __ipv6_addr_src_scope(__ipv6_addr_type(addr));
568 }
569 
570 static inline bool __ipv6_addr_needs_scope_id(int type)
571 {
572 	return type & IPV6_ADDR_LINKLOCAL ||
573 	       (type & IPV6_ADDR_MULTICAST &&
574 		(type & (IPV6_ADDR_LOOPBACK|IPV6_ADDR_LINKLOCAL)));
575 }
576 
577 static inline __u32 ipv6_iface_scope_id(const struct in6_addr *addr, int iface)
578 {
579 	return __ipv6_addr_needs_scope_id(__ipv6_addr_type(addr)) ? iface : 0;
580 }
581 
582 static inline int ipv6_addr_cmp(const struct in6_addr *a1, const struct in6_addr *a2)
583 {
584 	return memcmp(a1, a2, sizeof(struct in6_addr));
585 }
586 
587 static inline bool
588 ipv6_masked_addr_cmp(const struct in6_addr *a1, const struct in6_addr *m,
589 		     const struct in6_addr *a2)
590 {
591 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
592 	const unsigned long *ul1 = (const unsigned long *)a1;
593 	const unsigned long *ulm = (const unsigned long *)m;
594 	const unsigned long *ul2 = (const unsigned long *)a2;
595 
596 	return !!(((ul1[0] ^ ul2[0]) & ulm[0]) |
597 		  ((ul1[1] ^ ul2[1]) & ulm[1]));
598 #else
599 	return !!(((a1->s6_addr32[0] ^ a2->s6_addr32[0]) & m->s6_addr32[0]) |
600 		  ((a1->s6_addr32[1] ^ a2->s6_addr32[1]) & m->s6_addr32[1]) |
601 		  ((a1->s6_addr32[2] ^ a2->s6_addr32[2]) & m->s6_addr32[2]) |
602 		  ((a1->s6_addr32[3] ^ a2->s6_addr32[3]) & m->s6_addr32[3]));
603 #endif
604 }
605 
606 static inline void ipv6_addr_prefix(struct in6_addr *pfx,
607 				    const struct in6_addr *addr,
608 				    int plen)
609 {
610 	/* caller must guarantee 0 <= plen <= 128 */
611 	int o = plen >> 3,
612 	    b = plen & 0x7;
613 
614 	memset(pfx->s6_addr, 0, sizeof(pfx->s6_addr));
615 	memcpy(pfx->s6_addr, addr, o);
616 	if (b != 0)
617 		pfx->s6_addr[o] = addr->s6_addr[o] & (0xff00 >> b);
618 }
619 
620 static inline void ipv6_addr_prefix_copy(struct in6_addr *addr,
621 					 const struct in6_addr *pfx,
622 					 int plen)
623 {
624 	/* caller must guarantee 0 <= plen <= 128 */
625 	int o = plen >> 3,
626 	    b = plen & 0x7;
627 
628 	memcpy(addr->s6_addr, pfx, o);
629 	if (b != 0) {
630 		addr->s6_addr[o] &= ~(0xff00 >> b);
631 		addr->s6_addr[o] |= (pfx->s6_addr[o] & (0xff00 >> b));
632 	}
633 }
634 
635 static inline void __ipv6_addr_set_half(__be32 *addr,
636 					__be32 wh, __be32 wl)
637 {
638 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
639 #if defined(__BIG_ENDIAN)
640 	if (__builtin_constant_p(wh) && __builtin_constant_p(wl)) {
641 		*(__force u64 *)addr = ((__force u64)(wh) << 32 | (__force u64)(wl));
642 		return;
643 	}
644 #elif defined(__LITTLE_ENDIAN)
645 	if (__builtin_constant_p(wl) && __builtin_constant_p(wh)) {
646 		*(__force u64 *)addr = ((__force u64)(wl) << 32 | (__force u64)(wh));
647 		return;
648 	}
649 #endif
650 #endif
651 	addr[0] = wh;
652 	addr[1] = wl;
653 }
654 
655 static inline void ipv6_addr_set(struct in6_addr *addr,
656 				     __be32 w1, __be32 w2,
657 				     __be32 w3, __be32 w4)
658 {
659 	__ipv6_addr_set_half(&addr->s6_addr32[0], w1, w2);
660 	__ipv6_addr_set_half(&addr->s6_addr32[2], w3, w4);
661 }
662 
663 static inline bool ipv6_addr_equal(const struct in6_addr *a1,
664 				   const struct in6_addr *a2)
665 {
666 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
667 	const unsigned long *ul1 = (const unsigned long *)a1;
668 	const unsigned long *ul2 = (const unsigned long *)a2;
669 
670 	return ((ul1[0] ^ ul2[0]) | (ul1[1] ^ ul2[1])) == 0UL;
671 #else
672 	return ((a1->s6_addr32[0] ^ a2->s6_addr32[0]) |
673 		(a1->s6_addr32[1] ^ a2->s6_addr32[1]) |
674 		(a1->s6_addr32[2] ^ a2->s6_addr32[2]) |
675 		(a1->s6_addr32[3] ^ a2->s6_addr32[3])) == 0;
676 #endif
677 }
678 
679 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
680 static inline bool __ipv6_prefix_equal64_half(const __be64 *a1,
681 					      const __be64 *a2,
682 					      unsigned int len)
683 {
684 	if (len && ((*a1 ^ *a2) & cpu_to_be64((~0UL) << (64 - len))))
685 		return false;
686 	return true;
687 }
688 
689 static inline bool ipv6_prefix_equal(const struct in6_addr *addr1,
690 				     const struct in6_addr *addr2,
691 				     unsigned int prefixlen)
692 {
693 	const __be64 *a1 = (const __be64 *)addr1;
694 	const __be64 *a2 = (const __be64 *)addr2;
695 
696 	if (prefixlen >= 64) {
697 		if (a1[0] ^ a2[0])
698 			return false;
699 		return __ipv6_prefix_equal64_half(a1 + 1, a2 + 1, prefixlen - 64);
700 	}
701 	return __ipv6_prefix_equal64_half(a1, a2, prefixlen);
702 }
703 #else
704 static inline bool ipv6_prefix_equal(const struct in6_addr *addr1,
705 				     const struct in6_addr *addr2,
706 				     unsigned int prefixlen)
707 {
708 	const __be32 *a1 = addr1->s6_addr32;
709 	const __be32 *a2 = addr2->s6_addr32;
710 	unsigned int pdw, pbi;
711 
712 	/* check complete u32 in prefix */
713 	pdw = prefixlen >> 5;
714 	if (pdw && memcmp(a1, a2, pdw << 2))
715 		return false;
716 
717 	/* check incomplete u32 in prefix */
718 	pbi = prefixlen & 0x1f;
719 	if (pbi && ((a1[pdw] ^ a2[pdw]) & htonl((0xffffffff) << (32 - pbi))))
720 		return false;
721 
722 	return true;
723 }
724 #endif
725 
726 static inline bool ipv6_addr_any(const struct in6_addr *a)
727 {
728 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
729 	const unsigned long *ul = (const unsigned long *)a;
730 
731 	return (ul[0] | ul[1]) == 0UL;
732 #else
733 	return (a->s6_addr32[0] | a->s6_addr32[1] |
734 		a->s6_addr32[2] | a->s6_addr32[3]) == 0;
735 #endif
736 }
737 
738 static inline u32 ipv6_addr_hash(const struct in6_addr *a)
739 {
740 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
741 	const unsigned long *ul = (const unsigned long *)a;
742 	unsigned long x = ul[0] ^ ul[1];
743 
744 	return (u32)(x ^ (x >> 32));
745 #else
746 	return (__force u32)(a->s6_addr32[0] ^ a->s6_addr32[1] ^
747 			     a->s6_addr32[2] ^ a->s6_addr32[3]);
748 #endif
749 }
750 
751 /* more secured version of ipv6_addr_hash() */
752 static inline u32 __ipv6_addr_jhash(const struct in6_addr *a, const u32 initval)
753 {
754 	u32 v = (__force u32)a->s6_addr32[0] ^ (__force u32)a->s6_addr32[1];
755 
756 	return jhash_3words(v,
757 			    (__force u32)a->s6_addr32[2],
758 			    (__force u32)a->s6_addr32[3],
759 			    initval);
760 }
761 
762 static inline bool ipv6_addr_loopback(const struct in6_addr *a)
763 {
764 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
765 	const __be64 *be = (const __be64 *)a;
766 
767 	return (be[0] | (be[1] ^ cpu_to_be64(1))) == 0UL;
768 #else
769 	return (a->s6_addr32[0] | a->s6_addr32[1] |
770 		a->s6_addr32[2] | (a->s6_addr32[3] ^ cpu_to_be32(1))) == 0;
771 #endif
772 }
773 
774 /*
775  * Note that we must __force cast these to unsigned long to make sparse happy,
776  * since all of the endian-annotated types are fixed size regardless of arch.
777  */
778 static inline bool ipv6_addr_v4mapped(const struct in6_addr *a)
779 {
780 	return (
781 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
782 		*(unsigned long *)a |
783 #else
784 		(__force unsigned long)(a->s6_addr32[0] | a->s6_addr32[1]) |
785 #endif
786 		(__force unsigned long)(a->s6_addr32[2] ^
787 					cpu_to_be32(0x0000ffff))) == 0UL;
788 }
789 
790 static inline bool ipv6_addr_v4mapped_loopback(const struct in6_addr *a)
791 {
792 	return ipv6_addr_v4mapped(a) && ipv4_is_loopback(a->s6_addr32[3]);
793 }
794 
795 static inline u32 ipv6_portaddr_hash(const struct net *net,
796 				     const struct in6_addr *addr6,
797 				     unsigned int port)
798 {
799 	unsigned int hash, mix = net_hash_mix(net);
800 
801 	if (ipv6_addr_any(addr6))
802 		hash = jhash_1word(0, mix);
803 	else if (ipv6_addr_v4mapped(addr6))
804 		hash = jhash_1word((__force u32)addr6->s6_addr32[3], mix);
805 	else
806 		hash = jhash2((__force u32 *)addr6->s6_addr32, 4, mix);
807 
808 	return hash ^ port;
809 }
810 
811 /*
812  * Check for a RFC 4843 ORCHID address
813  * (Overlay Routable Cryptographic Hash Identifiers)
814  */
815 static inline bool ipv6_addr_orchid(const struct in6_addr *a)
816 {
817 	return (a->s6_addr32[0] & htonl(0xfffffff0)) == htonl(0x20010010);
818 }
819 
820 static inline bool ipv6_addr_is_multicast(const struct in6_addr *addr)
821 {
822 	return (addr->s6_addr32[0] & htonl(0xFF000000)) == htonl(0xFF000000);
823 }
824 
825 static inline void ipv6_addr_set_v4mapped(const __be32 addr,
826 					  struct in6_addr *v4mapped)
827 {
828 	ipv6_addr_set(v4mapped,
829 			0, 0,
830 			htonl(0x0000FFFF),
831 			addr);
832 }
833 
834 /*
835  * find the first different bit between two addresses
836  * length of address must be a multiple of 32bits
837  */
838 static inline int __ipv6_addr_diff32(const void *token1, const void *token2, int addrlen)
839 {
840 	const __be32 *a1 = token1, *a2 = token2;
841 	int i;
842 
843 	addrlen >>= 2;
844 
845 	for (i = 0; i < addrlen; i++) {
846 		__be32 xb = a1[i] ^ a2[i];
847 		if (xb)
848 			return i * 32 + 31 - __fls(ntohl(xb));
849 	}
850 
851 	/*
852 	 *	we should *never* get to this point since that
853 	 *	would mean the addrs are equal
854 	 *
855 	 *	However, we do get to it 8) And exacly, when
856 	 *	addresses are equal 8)
857 	 *
858 	 *	ip route add 1111::/128 via ...
859 	 *	ip route add 1111::/64 via ...
860 	 *	and we are here.
861 	 *
862 	 *	Ideally, this function should stop comparison
863 	 *	at prefix length. It does not, but it is still OK,
864 	 *	if returned value is greater than prefix length.
865 	 *					--ANK (980803)
866 	 */
867 	return addrlen << 5;
868 }
869 
870 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
871 static inline int __ipv6_addr_diff64(const void *token1, const void *token2, int addrlen)
872 {
873 	const __be64 *a1 = token1, *a2 = token2;
874 	int i;
875 
876 	addrlen >>= 3;
877 
878 	for (i = 0; i < addrlen; i++) {
879 		__be64 xb = a1[i] ^ a2[i];
880 		if (xb)
881 			return i * 64 + 63 - __fls(be64_to_cpu(xb));
882 	}
883 
884 	return addrlen << 6;
885 }
886 #endif
887 
888 static inline int __ipv6_addr_diff(const void *token1, const void *token2, int addrlen)
889 {
890 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
891 	if (__builtin_constant_p(addrlen) && !(addrlen & 7))
892 		return __ipv6_addr_diff64(token1, token2, addrlen);
893 #endif
894 	return __ipv6_addr_diff32(token1, token2, addrlen);
895 }
896 
897 static inline int ipv6_addr_diff(const struct in6_addr *a1, const struct in6_addr *a2)
898 {
899 	return __ipv6_addr_diff(a1, a2, sizeof(struct in6_addr));
900 }
901 
902 __be32 ipv6_select_ident(struct net *net,
903 			 const struct in6_addr *daddr,
904 			 const struct in6_addr *saddr);
905 __be32 ipv6_proxy_select_ident(struct net *net, struct sk_buff *skb);
906 
907 int ip6_dst_hoplimit(struct dst_entry *dst);
908 
909 static inline int ip6_sk_dst_hoplimit(struct ipv6_pinfo *np, struct flowi6 *fl6,
910 				      struct dst_entry *dst)
911 {
912 	int hlimit;
913 
914 	if (ipv6_addr_is_multicast(&fl6->daddr))
915 		hlimit = np->mcast_hops;
916 	else
917 		hlimit = np->hop_limit;
918 	if (hlimit < 0)
919 		hlimit = ip6_dst_hoplimit(dst);
920 	return hlimit;
921 }
922 
923 /* copy IPv6 saddr & daddr to flow_keys, possibly using 64bit load/store
924  * Equivalent to :	flow->v6addrs.src = iph->saddr;
925  *			flow->v6addrs.dst = iph->daddr;
926  */
927 static inline void iph_to_flow_copy_v6addrs(struct flow_keys *flow,
928 					    const struct ipv6hdr *iph)
929 {
930 	BUILD_BUG_ON(offsetof(typeof(flow->addrs), v6addrs.dst) !=
931 		     offsetof(typeof(flow->addrs), v6addrs.src) +
932 		     sizeof(flow->addrs.v6addrs.src));
933 	memcpy(&flow->addrs.v6addrs, &iph->addrs, sizeof(flow->addrs.v6addrs));
934 	flow->control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
935 }
936 
937 #if IS_ENABLED(CONFIG_IPV6)
938 
939 static inline bool ipv6_can_nonlocal_bind(struct net *net,
940 					  struct inet_sock *inet)
941 {
942 	return net->ipv6.sysctl.ip_nonlocal_bind ||
943 		inet->freebind || inet->transparent;
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 
956 static 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 
989 static 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
1002 static 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 }
1008 static inline int ip6_default_np_autolabel(struct net *net)
1009 {
1010 	return 0;
1011 }
1012 #endif
1013 
1014 #if IS_ENABLED(CONFIG_IPV6)
1015 static inline int ip6_multipath_hash_policy(const struct net *net)
1016 {
1017 	return net->ipv6.sysctl.multipath_hash_policy;
1018 }
1019 static inline u32 ip6_multipath_hash_fields(const struct net *net)
1020 {
1021 	return net->ipv6.sysctl.multipath_hash_fields;
1022 }
1023 #else
1024 static inline int ip6_multipath_hash_policy(const struct net *net)
1025 {
1026 	return 0;
1027 }
1028 static inline u32 ip6_multipath_hash_fields(const struct net *net)
1029 {
1030 	return 0;
1031 }
1032 #endif
1033 
1034 /*
1035  *	Header manipulation
1036  */
1037 static 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 
1043 static inline __be32 ip6_flowinfo(const struct ipv6hdr *hdr)
1044 {
1045 	return *(__be32 *)hdr & IPV6_FLOWINFO_MASK;
1046 }
1047 
1048 static inline __be32 ip6_flowlabel(const struct ipv6hdr *hdr)
1049 {
1050 	return *(__be32 *)hdr & IPV6_FLOWLABEL_MASK;
1051 }
1052 
1053 static inline u8 ip6_tclass(__be32 flowinfo)
1054 {
1055 	return ntohl(flowinfo & IPV6_TCLASS_MASK) >> IPV6_TCLASS_SHIFT;
1056 }
1057 
1058 static inline dscp_t ip6_dscp(__be32 flowinfo)
1059 {
1060 	return inet_dsfield_to_dscp(ip6_tclass(flowinfo));
1061 }
1062 
1063 static inline __be32 ip6_make_flowinfo(unsigned int tclass, __be32 flowlabel)
1064 {
1065 	return htonl(tclass << IPV6_TCLASS_SHIFT) | flowlabel;
1066 }
1067 
1068 static 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 
1081 int ipv6_rcv(struct sk_buff *skb, struct net_device *dev,
1082 	     struct packet_type *pt, struct net_device *orig_dev);
1083 void ipv6_list_rcv(struct list_head *head, struct packet_type *pt,
1084 		   struct net_device *orig_dev);
1085 
1086 int ip6_rcv_finish(struct net *net, struct sock *sk, struct sk_buff *skb);
1087 
1088 /*
1089  *	upper-layer output functions
1090  */
1091 int 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 
1094 int ip6_find_1stfragopt(struct sk_buff *skb, u8 **nexthdr);
1095 
1096 int 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 
1103 int ip6_push_pending_frames(struct sock *sk);
1104 
1105 void ip6_flush_pending_frames(struct sock *sk);
1106 
1107 int ip6_send_skb(struct sk_buff *skb);
1108 
1109 struct 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);
1112 struct 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 
1120 static 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 
1126 int ip6_dst_lookup(struct net *net, struct sock *sk, struct dst_entry **dst,
1127 		   struct flowi6 *fl6);
1128 struct dst_entry *ip6_dst_lookup_flow(struct net *net, const struct sock *sk, struct flowi6 *fl6,
1129 				      const struct in6_addr *final_dst);
1130 struct dst_entry *ip6_sk_dst_lookup_flow(struct sock *sk, struct flowi6 *fl6,
1131 					 const struct in6_addr *final_dst,
1132 					 bool connected);
1133 struct dst_entry *ip6_dst_lookup_tunnel(struct sk_buff *skb,
1134 					struct net_device *dev,
1135 					struct net *net, struct socket *sock,
1136 					struct in6_addr *saddr,
1137 					const struct ip_tunnel_info *info,
1138 					u8 protocol, bool use_cache);
1139 struct dst_entry *ip6_blackhole_route(struct net *net,
1140 				      struct dst_entry *orig_dst);
1141 
1142 /*
1143  *	skb processing functions
1144  */
1145 
1146 int ip6_output(struct net *net, struct sock *sk, struct sk_buff *skb);
1147 int ip6_forward(struct sk_buff *skb);
1148 int ip6_input(struct sk_buff *skb);
1149 int ip6_mc_input(struct sk_buff *skb);
1150 void ip6_protocol_deliver_rcu(struct net *net, struct sk_buff *skb, int nexthdr,
1151 			      bool have_final);
1152 
1153 int __ip6_local_out(struct net *net, struct sock *sk, struct sk_buff *skb);
1154 int ip6_local_out(struct net *net, struct sock *sk, struct sk_buff *skb);
1155 
1156 /*
1157  *	Extension header (options) processing
1158  */
1159 
1160 void ipv6_push_nfrag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt,
1161 			  u8 *proto, struct in6_addr **daddr_p,
1162 			  struct in6_addr *saddr);
1163 void ipv6_push_frag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt,
1164 			 u8 *proto);
1165 
1166 int ipv6_skip_exthdr(const struct sk_buff *, int start, u8 *nexthdrp,
1167 		     __be16 *frag_offp);
1168 
1169 bool ipv6_ext_hdr(u8 nexthdr);
1170 
1171 enum {
1172 	IP6_FH_F_FRAG		= (1 << 0),
1173 	IP6_FH_F_AUTH		= (1 << 1),
1174 	IP6_FH_F_SKIP_RH	= (1 << 2),
1175 };
1176 
1177 /* find specified header and get offset to it */
1178 int ipv6_find_hdr(const struct sk_buff *skb, unsigned int *offset, int target,
1179 		  unsigned short *fragoff, int *fragflg);
1180 
1181 int ipv6_find_tlv(const struct sk_buff *skb, int offset, int type);
1182 
1183 struct in6_addr *fl6_update_dst(struct flowi6 *fl6,
1184 				const struct ipv6_txoptions *opt,
1185 				struct in6_addr *orig);
1186 
1187 /*
1188  *	socket options (ipv6_sockglue.c)
1189  */
1190 DECLARE_STATIC_KEY_FALSE(ip6_min_hopcount);
1191 
1192 int do_ipv6_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval,
1193 		       unsigned int optlen);
1194 int ipv6_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval,
1195 		    unsigned int optlen);
1196 int do_ipv6_getsockopt(struct sock *sk, int level, int optname,
1197 		       sockptr_t optval, sockptr_t optlen);
1198 int ipv6_getsockopt(struct sock *sk, int level, int optname,
1199 		    char __user *optval, int __user *optlen);
1200 
1201 int __ip6_datagram_connect(struct sock *sk, struct sockaddr *addr,
1202 			   int addr_len);
1203 int ip6_datagram_connect(struct sock *sk, struct sockaddr *addr, int addr_len);
1204 int ip6_datagram_connect_v6_only(struct sock *sk, struct sockaddr *addr,
1205 				 int addr_len);
1206 int ip6_datagram_dst_update(struct sock *sk, bool fix_sk_saddr);
1207 void ip6_datagram_release_cb(struct sock *sk);
1208 
1209 int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len,
1210 		    int *addr_len);
1211 int ipv6_recv_rxpmtu(struct sock *sk, struct msghdr *msg, int len,
1212 		     int *addr_len);
1213 void ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err, __be16 port,
1214 		     u32 info, u8 *payload);
1215 void ipv6_local_error(struct sock *sk, int err, struct flowi6 *fl6, u32 info);
1216 void ipv6_local_rxpmtu(struct sock *sk, struct flowi6 *fl6, u32 mtu);
1217 
1218 void inet6_cleanup_sock(struct sock *sk);
1219 void inet6_sock_destruct(struct sock *sk);
1220 int inet6_release(struct socket *sock);
1221 int inet6_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len);
1222 int inet6_getname(struct socket *sock, struct sockaddr *uaddr,
1223 		  int peer);
1224 int inet6_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg);
1225 int inet6_compat_ioctl(struct socket *sock, unsigned int cmd,
1226 		unsigned long arg);
1227 
1228 int inet6_hash_connect(struct inet_timewait_death_row *death_row,
1229 			      struct sock *sk);
1230 int inet6_sendmsg(struct socket *sock, struct msghdr *msg, size_t size);
1231 int inet6_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
1232 		  int flags);
1233 
1234 /*
1235  * reassembly.c
1236  */
1237 extern const struct proto_ops inet6_stream_ops;
1238 extern const struct proto_ops inet6_dgram_ops;
1239 extern const struct proto_ops inet6_sockraw_ops;
1240 
1241 struct group_source_req;
1242 struct group_filter;
1243 
1244 int ip6_mc_source(int add, int omode, struct sock *sk,
1245 		  struct group_source_req *pgsr);
1246 int ip6_mc_msfilter(struct sock *sk, struct group_filter *gsf,
1247 		  struct sockaddr_storage *list);
1248 int ip6_mc_msfget(struct sock *sk, struct group_filter *gsf,
1249 		  sockptr_t optval, size_t ss_offset);
1250 
1251 #ifdef CONFIG_PROC_FS
1252 int ac6_proc_init(struct net *net);
1253 void ac6_proc_exit(struct net *net);
1254 int raw6_proc_init(void);
1255 void raw6_proc_exit(void);
1256 int tcp6_proc_init(struct net *net);
1257 void tcp6_proc_exit(struct net *net);
1258 int udp6_proc_init(struct net *net);
1259 void udp6_proc_exit(struct net *net);
1260 int udplite6_proc_init(void);
1261 void udplite6_proc_exit(void);
1262 int ipv6_misc_proc_init(void);
1263 void ipv6_misc_proc_exit(void);
1264 int snmp6_register_dev(struct inet6_dev *idev);
1265 int snmp6_unregister_dev(struct inet6_dev *idev);
1266 
1267 #else
1268 static inline int ac6_proc_init(struct net *net) { return 0; }
1269 static inline void ac6_proc_exit(struct net *net) { }
1270 static inline int snmp6_register_dev(struct inet6_dev *idev) { return 0; }
1271 static inline int snmp6_unregister_dev(struct inet6_dev *idev) { return 0; }
1272 #endif
1273 
1274 #ifdef CONFIG_SYSCTL
1275 struct ctl_table *ipv6_icmp_sysctl_init(struct net *net);
1276 struct ctl_table *ipv6_route_sysctl_init(struct net *net);
1277 int ipv6_sysctl_register(void);
1278 void ipv6_sysctl_unregister(void);
1279 #endif
1280 
1281 int ipv6_sock_mc_join(struct sock *sk, int ifindex,
1282 		      const struct in6_addr *addr);
1283 int ipv6_sock_mc_join_ssm(struct sock *sk, int ifindex,
1284 			  const struct in6_addr *addr, unsigned int mode);
1285 int ipv6_sock_mc_drop(struct sock *sk, int ifindex,
1286 		      const struct in6_addr *addr);
1287 
1288 static inline int ip6_sock_set_v6only(struct sock *sk)
1289 {
1290 	if (inet_sk(sk)->inet_num)
1291 		return -EINVAL;
1292 	lock_sock(sk);
1293 	sk->sk_ipv6only = true;
1294 	release_sock(sk);
1295 	return 0;
1296 }
1297 
1298 static inline void ip6_sock_set_recverr(struct sock *sk)
1299 {
1300 	lock_sock(sk);
1301 	inet6_sk(sk)->recverr = true;
1302 	release_sock(sk);
1303 }
1304 
1305 static inline int __ip6_sock_set_addr_preferences(struct sock *sk, int val)
1306 {
1307 	unsigned int pref = 0;
1308 	unsigned int prefmask = ~0;
1309 
1310 	/* check PUBLIC/TMP/PUBTMP_DEFAULT conflicts */
1311 	switch (val & (IPV6_PREFER_SRC_PUBLIC |
1312 		       IPV6_PREFER_SRC_TMP |
1313 		       IPV6_PREFER_SRC_PUBTMP_DEFAULT)) {
1314 	case IPV6_PREFER_SRC_PUBLIC:
1315 		pref |= IPV6_PREFER_SRC_PUBLIC;
1316 		prefmask &= ~(IPV6_PREFER_SRC_PUBLIC |
1317 			      IPV6_PREFER_SRC_TMP);
1318 		break;
1319 	case IPV6_PREFER_SRC_TMP:
1320 		pref |= IPV6_PREFER_SRC_TMP;
1321 		prefmask &= ~(IPV6_PREFER_SRC_PUBLIC |
1322 			      IPV6_PREFER_SRC_TMP);
1323 		break;
1324 	case IPV6_PREFER_SRC_PUBTMP_DEFAULT:
1325 		prefmask &= ~(IPV6_PREFER_SRC_PUBLIC |
1326 			      IPV6_PREFER_SRC_TMP);
1327 		break;
1328 	case 0:
1329 		break;
1330 	default:
1331 		return -EINVAL;
1332 	}
1333 
1334 	/* check HOME/COA conflicts */
1335 	switch (val & (IPV6_PREFER_SRC_HOME | IPV6_PREFER_SRC_COA)) {
1336 	case IPV6_PREFER_SRC_HOME:
1337 		prefmask &= ~IPV6_PREFER_SRC_COA;
1338 		break;
1339 	case IPV6_PREFER_SRC_COA:
1340 		pref |= IPV6_PREFER_SRC_COA;
1341 		break;
1342 	case 0:
1343 		break;
1344 	default:
1345 		return -EINVAL;
1346 	}
1347 
1348 	/* check CGA/NONCGA conflicts */
1349 	switch (val & (IPV6_PREFER_SRC_CGA|IPV6_PREFER_SRC_NONCGA)) {
1350 	case IPV6_PREFER_SRC_CGA:
1351 	case IPV6_PREFER_SRC_NONCGA:
1352 	case 0:
1353 		break;
1354 	default:
1355 		return -EINVAL;
1356 	}
1357 
1358 	inet6_sk(sk)->srcprefs = (inet6_sk(sk)->srcprefs & prefmask) | pref;
1359 	return 0;
1360 }
1361 
1362 static inline int ip6_sock_set_addr_preferences(struct sock *sk, bool val)
1363 {
1364 	int ret;
1365 
1366 	lock_sock(sk);
1367 	ret = __ip6_sock_set_addr_preferences(sk, val);
1368 	release_sock(sk);
1369 	return ret;
1370 }
1371 
1372 static inline void ip6_sock_set_recvpktinfo(struct sock *sk)
1373 {
1374 	lock_sock(sk);
1375 	inet6_sk(sk)->rxopt.bits.rxinfo = true;
1376 	release_sock(sk);
1377 }
1378 
1379 #endif /* _NET_IPV6_H */
1380