summaryrefslogtreecommitdiff
path: root/include/net/ipv6.h
blob: 574337fe72ddbd3038c061dab5aef142ea0f068b (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
/*
 *	Linux INET6 implementation
 *
 *	Authors:
 *	Pedro Roque		<roque@di.fc.ul.pt>
 *
 *	This program is free software; you can redistribute it and/or
 *      modify it under the terms of the GNU General Public License
 *      as published by the Free Software Foundation; either version
 *      2 of the License, or (at your option) any later version.
 */

#ifndef _NET_IPV6_H
#define _NET_IPV6_H

#include <linux/ipv6.h>
#include <linux/hardirq.h>
#include <linux/jhash.h>
#include <net/if_inet6.h>
#include <net/ndisc.h>
#include <net/flow.h>
#include <net/snmp.h>

#define SIN6_LEN_RFC2133	24

#define IPV6_MAXPLEN		65535

/*
 *	NextHeader field of IPv6 header
 */

#define NEXTHDR_HOP		0	/* Hop-by-hop option header. */
#define NEXTHDR_TCP		6	/* TCP segment. */
#define NEXTHDR_UDP		17	/* UDP message. */
#define NEXTHDR_IPV6		41	/* IPv6 in IPv6 */
#define NEXTHDR_ROUTING		43	/* Routing header. */
#define NEXTHDR_FRAGMENT	44	/* Fragmentation/reassembly header. */
#define NEXTHDR_GRE		47	/* GRE header. */
#define NEXTHDR_ESP		50	/* Encapsulating security payload. */
#define NEXTHDR_AUTH		51	/* Authentication header. */
#define NEXTHDR_ICMP		58	/* ICMP for IPv6. */
#define NEXTHDR_NONE		59	/* No next header */
#define NEXTHDR_DEST		60	/* Destination options header. */
#define NEXTHDR_SCTP		132	/* SCTP message. */
#define NEXTHDR_MOBILITY	135	/* Mobility header. */

#define NEXTHDR_MAX		255



#define IPV6_DEFAULT_HOPLIMIT   64
#define IPV6_DEFAULT_MCASTHOPS	1

/*
 *	Addr type
 *	
 *	type	-	unicast | multicast
 *	scope	-	local	| site	    | global
 *	v4	-	compat
 *	v4mapped
 *	any
 *	loopback
 */

#define IPV6_ADDR_ANY		0x0000U

#define IPV6_ADDR_UNICAST      	0x0001U	
#define IPV6_ADDR_MULTICAST    	0x0002U	

#define IPV6_ADDR_LOOPBACK	0x0010U
#define IPV6_ADDR_LINKLOCAL	0x0020U
#define IPV6_ADDR_SITELOCAL	0x0040U

#define IPV6_ADDR_COMPATv4	0x0080U

#define IPV6_ADDR_SCOPE_MASK	0x00f0U

#define IPV6_ADDR_MAPPED	0x1000U

/*
 *	Addr scopes
 */
#define IPV6_ADDR_MC_SCOPE(a)	\
	((a)->s6_addr[1] & 0x0f)	/* nonstandard */
#define __IPV6_ADDR_SCOPE_INVALID	-1
#define IPV6_ADDR_SCOPE_NODELOCAL	0x01
#define IPV6_ADDR_SCOPE_LINKLOCAL	0x02
#define IPV6_ADDR_SCOPE_SITELOCAL	0x05
#define IPV6_ADDR_SCOPE_ORGLOCAL	0x08
#define IPV6_ADDR_SCOPE_GLOBAL		0x0e

/*
 *	Addr flags
 */
#define IPV6_ADDR_MC_FLAG_TRANSIENT(a)	\
	((a)->s6_addr[1] & 0x10)
#define IPV6_ADDR_MC_FLAG_PREFIX(a)	\
	((a)->s6_addr[1] & 0x20)
#define IPV6_ADDR_MC_FLAG_RENDEZVOUS(a)	\
	((a)->s6_addr[1] & 0x40)

/*
 *	fragmentation header
 */

struct frag_hdr {
	__u8	nexthdr;
	__u8	reserved;
	__be16	frag_off;
	__be32	identification;
};

#define	IP6_MF		0x0001
#define	IP6_OFFSET	0xFFF8

#define IP6_REPLY_MARK(net, mark) \
	((net)->ipv6.sysctl.fwmark_reflect ? (mark) : 0)

#include <net/sock.h>

/* sysctls */
extern int sysctl_mld_max_msf;

#define _DEVINC(net, statname, modifier, idev, field)			\
({									\
	struct inet6_dev *_idev = (idev);				\
	if (likely(_idev != NULL))					\
		SNMP_INC_STATS##modifier((_idev)->stats.statname, (field)); \
	SNMP_INC_STATS##modifier((net)->mib.statname##_statistics, (field));\
})

/* per device counters are atomic_long_t */
#define _DEVINCATOMIC(net, statname, modifier, idev, field)		\
({									\
	struct inet6_dev *_idev = (idev);				\
	if (likely(_idev != NULL))					\
		SNMP_INC_STATS_ATOMIC_LONG((_idev)->stats.statname##dev, (field)); \
	SNMP_INC_STATS##modifier((net)->mib.statname##_statistics, (field));\
})

/* per device and per net counters are atomic_long_t */
#define _DEVINC_ATOMIC_ATOMIC(net, statname, idev, field)		\
({									\
	struct inet6_dev *_idev = (idev);				\
	if (likely(_idev != NULL))					\
		SNMP_INC_STATS_ATOMIC_LONG((_idev)->stats.statname##dev, (field)); \
	SNMP_INC_STATS_ATOMIC_LONG((net)->mib.statname##_statistics, (field));\
})

#define _DEVADD(net, statname, modifier, idev, field, val)		\
({									\
	struct inet6_dev *_idev = (idev);				\
	if (likely(_idev != NULL))					\
		SNMP_ADD_STATS##modifier((_idev)->stats.statname, (field), (val)); \
	SNMP_ADD_STATS##modifier((net)->mib.statname##_statistics, (field), (val));\
})

#define _DEVUPD(net, statname, modifier, idev, field, val)		\
({									\
	struct inet6_dev *_idev = (idev);				\
	if (likely(_idev != NULL))					\
		SNMP_UPD_PO_STATS##modifier((_idev)->stats.statname, field, (val)); \
	SNMP_UPD_PO_STATS##modifier((net)->mib.statname##_statistics, field, (val));\
})

/* MIBs */

#define IP6_INC_STATS(net, idev,field)		\
		_DEVINC(net, ipv6, 64, idev, field)
#define IP6_INC_STATS_BH(net, idev,field)	\
		_DEVINC(net, ipv6, 64_BH, idev, field)
#define IP6_ADD_STATS(net, idev,field,val)	\
		_DEVADD(net, ipv6, 64, idev, field, val)
#define IP6_ADD_STATS_BH(net, idev,field,val)	\
		_DEVADD(net, ipv6, 64_BH, idev, field, val)
#define IP6_UPD_PO_STATS(net, idev,field,val)   \
		_DEVUPD(net, ipv6, 64, idev, field, val)
#define IP6_UPD_PO_STATS_BH(net, idev,field,val)   \
		_DEVUPD(net, ipv6, 64_BH, idev, field, val)
#define ICMP6_INC_STATS(net, idev, field)	\
		_DEVINCATOMIC(net, icmpv6, , idev, field)
#define ICMP6_INC_STATS_BH(net, idev, field)	\
		_DEVINCATOMIC(net, icmpv6, _BH, idev, field)

#define ICMP6MSGOUT_INC_STATS(net, idev, field)		\
	_DEVINC_ATOMIC_ATOMIC(net, icmpv6msg, idev, field +256)
#define ICMP6MSGOUT_INC_STATS_BH(net, idev, field)	\
	_DEVINC_ATOMIC_ATOMIC(net, icmpv6msg, idev, field +256)
#define ICMP6MSGIN_INC_STATS_BH(net, idev, field)	\
	_DEVINC_ATOMIC_ATOMIC(net, icmpv6msg, idev, field)

struct ip6_ra_chain {
	struct ip6_ra_chain	*next;
	struct sock		*sk;
	int			sel;
	void			(*destructor)(struct sock *);
};

extern struct ip6_ra_chain	*ip6_ra_chain;
extern rwlock_t ip6_ra_lock;

/*
   This structure is prepared by protocol, when parsing
   ancillary data and passed to IPv6.
 */

struct ipv6_txoptions {
	/* Length of this structure */
	int			tot_len;

	/* length of extension headers   */

	__u16			opt_flen;	/* after fragment hdr */
	__u16			opt_nflen;	/* before fragment hdr */

	struct ipv6_opt_hdr	*hopopt;
	struct ipv6_opt_hdr	*dst0opt;
	struct ipv6_rt_hdr	*srcrt;	/* Routing Header */
	struct ipv6_opt_hdr	*dst1opt;

	/* Option buffer, as read by IPV6_PKTOPTIONS, starts here. */
};

struct ip6_flowlabel {
	struct ip6_flowlabel __rcu *next;
	__be32			label;
	atomic_t		users;
	struct in6_addr		dst;
	struct ipv6_txoptions	*opt;
	unsigned long		linger;
	struct rcu_head		rcu;
	u8			share;
	union {
		struct pid *pid;
		kuid_t uid;
	} owner;
	unsigned long		lastuse;
	unsigned long		expires;
	struct net		*fl_net;
};

#define IPV6_FLOWINFO_MASK	cpu_to_be32(0x0FFFFFFF)
#define IPV6_FLOWLABEL_MASK	cpu_to_be32(0x000FFFFF)
#define IPV6_TCLASS_MASK (IPV6_FLOWINFO_MASK & ~IPV6_FLOWLABEL_MASK)
#define IPV6_TCLASS_SHIFT	20

struct ipv6_fl_socklist {
	struct ipv6_fl_socklist	__rcu	*next;
	struct ip6_flowlabel		*fl;
	struct rcu_head			rcu;
};

struct ip6_flowlabel *fl6_sock_lookup(struct sock *sk, __be32 label);
struct ipv6_txoptions *fl6_merge_options(struct ipv6_txoptions *opt_space,
					 struct ip6_flowlabel *fl,
					 struct ipv6_txoptions *fopt);
void fl6_free_socklist(struct sock *sk);
int ipv6_flowlabel_opt(struct sock *sk, char __user *optval, int optlen);
int ipv6_flowlabel_opt_get(struct sock *sk, struct in6_flowlabel_req *freq,
			   int flags);
int ip6_flowlabel_init(void);
void ip6_flowlabel_cleanup(void);

static inline void fl6_sock_release(struct ip6_flowlabel *fl)
{
	if (fl)
		atomic_dec(&fl->users);
}

void icmpv6_notify(struct sk_buff *skb, u8 type, u8 code, __be32 info);

int icmpv6_push_pending_frames(struct sock *sk, struct flowi6 *fl6,
			       struct icmp6hdr *thdr, int len);

int ip6_ra_control(struct sock *sk, int sel);

int ipv6_parse_hopopts(struct sk_buff *skb);

struct ipv6_txoptions *ipv6_dup_options(struct sock *sk,
					struct ipv6_txoptions *opt);
struct ipv6_txoptions *ipv6_renew_options(struct sock *sk,
					  struct ipv6_txoptions *opt,
					  int newtype,
					  struct ipv6_opt_hdr __user *newopt,
					  int newoptlen);
struct ipv6_txoptions *ipv6_fixup_options(struct ipv6_txoptions *opt_space,
					  struct ipv6_txoptions *opt);

bool ipv6_opt_accepted(const struct sock *sk, const struct sk_buff *skb);

static inline bool ipv6_accept_ra(struct inet6_dev *idev)
{
	/* If forwarding is enabled, RA are not accepted unless the special
	 * hybrid mode (accept_ra=2) is enabled.
	 */
	return idev->cnf.forwarding ? idev->cnf.accept_ra == 2 :
	    idev->cnf.accept_ra;
}

#if IS_ENABLED(CONFIG_IPV6)
static inline int ip6_frag_nqueues(struct net *net)
{
	return net->ipv6.frags.nqueues;
}

static inline int ip6_frag_mem(struct net *net)
{
	return sum_frag_mem_limit(&net->ipv6.frags);
}
#endif

#define IPV6_FRAG_HIGH_THRESH	(4 * 1024*1024)	/* 4194304 */
#define IPV6_FRAG_LOW_THRESH	(3 * 1024*1024)	/* 3145728 */
#define IPV6_FRAG_TIMEOUT	(60 * HZ)	/* 60 seconds */

int __ipv6_addr_type(const struct in6_addr *addr);
static inline int ipv6_addr_type(const struct in6_addr *addr)
{
	return __ipv6_addr_type(addr) & 0xffff;
}

static inline int ipv6_addr_scope(const struct in6_addr *addr)
{
	return __ipv6_addr_type(addr) & IPV6_ADDR_SCOPE_MASK;
}

static inline int __ipv6_addr_src_scope(int type)
{
	return (type == IPV6_ADDR_ANY) ? __IPV6_ADDR_SCOPE_INVALID : (type >> 16);
}

static inline int ipv6_addr_src_scope(const struct in6_addr *addr)
{
	return __ipv6_addr_src_scope(__ipv6_addr_type(addr));
}

static inline bool __ipv6_addr_needs_scope_id(int type)
{
	return type & IPV6_ADDR_LINKLOCAL ||
	       (type & IPV6_ADDR_MULTICAST &&
		(type & (IPV6_ADDR_LOOPBACK|IPV6_ADDR_LINKLOCAL)));
}

static inline __u32 ipv6_iface_scope_id(const struct in6_addr *addr, int iface)
{
	return __ipv6_addr_needs_scope_id(__ipv6_addr_type(addr)) ? iface : 0;
}

static inline int ipv6_addr_cmp(const struct in6_addr *a1, const struct in6_addr *a2)
{
	return memcmp(a1, a2, sizeof(struct in6_addr));
}

static inline bool
ipv6_masked_addr_cmp(const struct in6_addr *a1, const struct in6_addr *m,
		     const struct in6_addr *a2)
{
#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
	const unsigned long *ul1 = (const unsigned long *)a1;
	const unsigned long *ulm = (const unsigned long *)m;
	const unsigned long *ul2 = (const unsigned long *)a2;

	return !!(((ul1[0] ^ ul2[0]) & ulm[0]) |
		  ((ul1[1] ^ ul2[1]) & ulm[1]));
#else
	return !!(((a1->s6_addr32[0] ^ a2->s6_addr32[0]) & m->s6_addr32[0]) |
		  ((a1->s6_addr32[1] ^ a2->s6_addr32[1]) & m->s6_addr32[1]) |
		  ((a1->s6_addr32[2] ^ a2->s6_addr32[2]) & m->s6_addr32[2]) |
		  ((a1->s6_addr32[3] ^ a2->s6_addr32[3]) & m->s6_addr32[3]));
#endif
}

static inline void ipv6_addr_prefix(struct in6_addr *pfx, 
				    const struct in6_addr *addr,
				    int plen)
{
	/* caller must guarantee 0 <= plen <= 128 */
	int o = plen >> 3,
	    b = plen & 0x7;

	memset(pfx->s6_addr, 0, sizeof(pfx->s6_addr));
	memcpy(pfx->s6_addr, addr, o);
	if (b != 0)
		pfx->s6_addr[o] = addr->s6_addr[o] & (0xff00 >> b);
}

static inline void __ipv6_addr_set_half(__be32 *addr,
					__be32 wh, __be32 wl)
{
#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
#if defined(__BIG_ENDIAN)
	if (__builtin_constant_p(wh) && __builtin_constant_p(wl)) {
		*(__force u64 *)addr = ((__force u64)(wh) << 32 | (__force u64)(wl));
		return;
	}
#elif defined(__LITTLE_ENDIAN)
	if (__builtin_constant_p(wl) && __builtin_constant_p(wh)) {
		*(__force u64 *)addr = ((__force u64)(wl) << 32 | (__force u64)(wh));
		return;
	}
#endif
#endif
	addr[0] = wh;
	addr[1] = wl;
}

static inline void ipv6_addr_set(struct in6_addr *addr, 
				     __be32 w1, __be32 w2,
				     __be32 w3, __be32 w4)
{
	__ipv6_addr_set_half(&addr->s6_addr32[0], w1, w2);
	__ipv6_addr_set_half(&addr->s6_addr32[2], w3, w4);
}

static inline bool ipv6_addr_equal(const struct in6_addr *a1,
				   const struct in6_addr *a2)
{
#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
	const unsigned long *ul1 = (const unsigned long *)a1;
	const unsigned long *ul2 = (const unsigned long *)a2;

	return ((ul1[0] ^ ul2[0]) | (ul1[1] ^ ul2[1])) == 0UL;
#else
	return ((a1->s6_addr32[0] ^ a2->s6_addr32[0]) |
		(a1->s6_addr32[1] ^ a2->s6_addr32[1]) |
		(a1->s6_addr32[2] ^ a2->s6_addr32[2]) |
		(a1->s6_addr32[3] ^ a2->s6_addr32[3])) == 0;
#endif
}

#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
static inline bool __ipv6_prefix_equal64_half(const __be64 *a1,
					      const __be64 *a2,
					      unsigned int len)
{
	if (len && ((*a1 ^ *a2) & cpu_to_be64((~0UL) << (64 - len))))
		return false;
	return true;
}

static inline bool ipv6_prefix_equal(const struct in6_addr *addr1,
				     const struct in6_addr *addr2,
				     unsigned int prefixlen)
{
	const __be64 *a1 = (const __be64 *)addr1;
	const __be64 *a2 = (const __be64 *)addr2;

	if (prefixlen >= 64) {
		if (a1[0] ^ a2[0])
			return false;
		return __ipv6_prefix_equal64_half(a1 + 1, a2 + 1, prefixlen - 64);
	}
	return __ipv6_prefix_equal64_half(a1, a2, prefixlen);
}
#else
static inline bool ipv6_prefix_equal(const struct in6_addr *addr1,
				     const struct in6_addr *addr2,
				     unsigned int prefixlen)
{
	const __be32 *a1 = addr1->s6_addr32;
	const __be32 *a2 = addr2->s6_addr32;
	unsigned int pdw, pbi;

	/* check complete u32 in prefix */
	pdw = prefixlen >> 5;
	if (pdw && memcmp(a1, a2, pdw << 2))
		return false;

	/* check incomplete u32 in prefix */
	pbi = prefixlen & 0x1f;
	if (pbi && ((a1[pdw] ^ a2[pdw]) & htonl((0xffffffff) << (32 - pbi))))
		return false;

	return true;
}
#endif

struct inet_frag_queue;

enum ip6_defrag_users {
	IP6_DEFRAG_LOCAL_DELIVER,
	IP6_DEFRAG_CONNTRACK_IN,
	__IP6_DEFRAG_CONNTRACK_IN	= IP6_DEFRAG_CONNTRACK_IN + USHRT_MAX,
	IP6_DEFRAG_CONNTRACK_OUT,
	__IP6_DEFRAG_CONNTRACK_OUT	= IP6_DEFRAG_CONNTRACK_OUT + USHRT_MAX,
	IP6_DEFRAG_CONNTRACK_BRIDGE_IN,
	__IP6_DEFRAG_CONNTRACK_BRIDGE_IN = IP6_DEFRAG_CONNTRACK_BRIDGE_IN + USHRT_MAX,
};

struct ip6_create_arg {
	__be32 id;
	u32 user;
	const struct in6_addr *src;
	const struct in6_addr *dst;
	u8 ecn;
};

void ip6_frag_init(struct inet_frag_queue *q, void *a);
bool ip6_frag_match(struct inet_frag_queue *q, void *a);

/*
 *	Equivalent of ipv4 struct ip
 */
struct frag_queue {
	struct inet_frag_queue	q;

	__be32			id;		/* fragment id		*/
	u32			user;
	struct in6_addr		saddr;
	struct in6_addr		daddr;

	int			iif;
	unsigned int		csum;
	__u16			nhoffset;
	u8			ecn;
};

void ip6_expire_frag_queue(struct net *net, struct frag_queue *fq,
			   struct inet_frags *frags);

static inline bool ipv6_addr_any(const struct in6_addr *a)
{
#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
	const unsigned long *ul = (const unsigned long *)a;

	return (ul[0] | ul[1]) == 0UL;
#else
	return (a->s6_addr32[0] | a->s6_addr32[1] |
		a->s6_addr32[2] | a->s6_addr32[3]) == 0;
#endif
}

static inline u32 ipv6_addr_hash(const struct in6_addr *a)
{
#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
	const unsigned long *ul = (const unsigned long *)a;
	unsigned long x = ul[0] ^ ul[1];

	return (u32)(x ^ (x >> 32));
#else
	return (__force u32)(a->s6_addr32[0] ^ a->s6_addr32[1] ^
			     a->s6_addr32[2] ^ a->s6_addr32[3]);
#endif
}

/* more secured version of ipv6_addr_hash() */
static inline u32 __ipv6_addr_jhash(const struct in6_addr *a, const u32 initval)
{
	u32 v = (__force u32)a->s6_addr32[0] ^ (__force u32)a->s6_addr32[1];

	return jhash_3words(v,
			    (__force u32)a->s6_addr32[2],
			    (__force u32)a->s6_addr32[3],
			    initval);
}

static inline bool ipv6_addr_loopback(const struct in6_addr *a)
{
#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
	const unsigned long *ul = (const unsigned long *)a;

	return (ul[0] | (ul[1] ^ cpu_to_be64(1))) == 0UL;
#else
	return (a->s6_addr32[0] | a->s6_addr32[1] |
		a->s6_addr32[2] | (a->s6_addr32[3] ^ htonl(1))) == 0;
#endif
}

static inline bool ipv6_addr_v4mapped(const struct in6_addr *a)
{
	return (
#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
		*(__be64 *)a |
#else
		(a->s6_addr32[0] | a->s6_addr32[1]) |
#endif
		(a->s6_addr32[2] ^ htonl(0x0000ffff))) == 0UL;
}

/*
 * Check for a RFC 4843 ORCHID address
 * (Overlay Routable Cryptographic Hash Identifiers)
 */
static inline bool ipv6_addr_orchid(const struct in6_addr *a)
{
	return (a->s6_addr32[0] & htonl(0xfffffff0)) == htonl(0x20010010);
}

static inline bool ipv6_addr_is_multicast(const struct in6_addr *addr)
{
	return (addr->s6_addr32[0] & htonl(0xFF000000)) == htonl(0xFF000000);
}

static inline void ipv6_addr_set_v4mapped(const __be32 addr,
					  struct in6_addr *v4mapped)
{
	ipv6_addr_set(v4mapped,
			0, 0,
			htonl(0x0000FFFF),
			addr);
}

/*
 * find the first different bit between two addresses
 * length of address must be a multiple of 32bits
 */
static inline int __ipv6_addr_diff32(const void *token1, const void *token2, int addrlen)
{
	const __be32 *a1 = token1, *a2 = token2;
	int i;

	addrlen >>= 2;

	for (i = 0; i < addrlen; i++) {
		__be32 xb = a1[i] ^ a2[i];
		if (xb)
			return i * 32 + 31 - __fls(ntohl(xb));
	}

	/*
	 *	we should *never* get to this point since that 
	 *	would mean the addrs are equal
	 *
	 *	However, we do get to it 8) And exacly, when
	 *	addresses are equal 8)
	 *
	 *	ip route add 1111::/128 via ...
	 *	ip route add 1111::/64 via ...
	 *	and we are here.
	 *
	 *	Ideally, this function should stop comparison
	 *	at prefix length. It does not, but it is still OK,
	 *	if returned value is greater than prefix length.
	 *					--ANK (980803)
	 */
	return addrlen << 5;
}

#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
static inline int __ipv6_addr_diff64(const void *token1, const void *token2, int addrlen)
{
	const __be64 *a1 = token1, *a2 = token2;
	int i;

	addrlen >>= 3;

	for (i = 0; i < addrlen; i++) {
		__be64 xb = a1[i] ^ a2[i];
		if (xb)
			return i * 64 + 63 - __fls(be64_to_cpu(xb));
	}

	return addrlen << 6;
}
#endif

static inline int __ipv6_addr_diff(const void *token1, const void *token2, int addrlen)
{
#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
	if (__builtin_constant_p(addrlen) && !(addrlen & 7))
		return __ipv6_addr_diff64(token1, token2, addrlen);
#endif
	return __ipv6_addr_diff32(token1, token2, addrlen);
}

static inline int ipv6_addr_diff(const struct in6_addr *a1, const struct in6_addr *a2)
{
	return __ipv6_addr_diff(a1, a2, sizeof(struct in6_addr));
}

int ip6_dst_hoplimit(struct dst_entry *dst);

static inline int ip6_sk_dst_hoplimit(struct ipv6_pinfo *np, struct flowi6 *fl6,
				      struct dst_entry *dst)
{
	int hlimit;

	if (ipv6_addr_is_multicast(&fl6->daddr))
		hlimit = np->mcast_hops;
	else
		hlimit = np->hop_limit;
	if (hlimit < 0)
		hlimit = ip6_dst_hoplimit(dst);
	return hlimit;
}

/*
 *	Header manipulation
 */
static inline void ip6_flow_hdr(struct ipv6hdr *hdr, unsigned int tclass,
				__be32 flowlabel)
{
	*(__be32 *)hdr = htonl(0x60000000 | (tclass << 20)) | flowlabel;
}

static inline __be32 ip6_flowinfo(const struct ipv6hdr *hdr)
{
	return *(__be32 *)hdr & IPV6_FLOWINFO_MASK;
}

static inline __be32 ip6_flowlabel(const struct ipv6hdr *hdr)
{
	return *(__be32 *)hdr & IPV6_FLOWLABEL_MASK;
}

static inline u8 ip6_tclass(__be32 flowinfo)
{
	return ntohl(flowinfo & IPV6_TCLASS_MASK) >> IPV6_TCLASS_SHIFT;
}
/*
 *	Prototypes exported by ipv6
 */

/*
 *	rcv function (called from netdevice level)
 */

int ipv6_rcv(struct sk_buff *skb, struct net_device *dev,
	     struct packet_type *pt, struct net_device *orig_dev);

int ip6_rcv_finish(struct sk_buff *skb);

/*
 *	upper-layer output functions
 */
int ip6_xmit(struct sock *sk, struct sk_buff *skb, struct flowi6 *fl6,
	     struct ipv6_txoptions *opt, int tclass);

int ip6_find_1stfragopt(struct sk_buff *skb, u8 **nexthdr);

int ip6_append_data(struct sock *sk,
		    int getfrag(void *from, char *to, int offset, int len,
				int odd, struct sk_buff *skb),
		    void *from, int length, int transhdrlen, int hlimit,
		    int tclass, struct ipv6_txoptions *opt, struct flowi6 *fl6,
		    struct rt6_info *rt, unsigned int flags, int dontfrag);

int ip6_push_pending_frames(struct sock *sk);

void ip6_flush_pending_frames(struct sock *sk);

int ip6_dst_lookup(struct sock *sk, struct dst_entry **dst, struct flowi6 *fl6);
struct dst_entry *ip6_dst_lookup_flow(struct sock *sk, struct flowi6 *fl6,
				      const struct in6_addr *final_dst);
struct dst_entry *ip6_sk_dst_lookup_flow(struct sock *sk, struct flowi6 *fl6,
					 const struct in6_addr *final_dst);
struct dst_entry *ip6_blackhole_route(struct net *net,
				      struct dst_entry *orig_dst);

/*
 *	skb processing functions
 */

int ip6_output(struct sock *sk, struct sk_buff *skb);
int ip6_forward(struct sk_buff *skb);
int ip6_input(struct sk_buff *skb);
int ip6_mc_input(struct sk_buff *skb);

int __ip6_local_out(struct sk_buff *skb);
int ip6_local_out(struct sk_buff *skb);

/*
 *	Extension header (options) processing
 */

void ipv6_push_nfrag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt,
			  u8 *proto, struct in6_addr **daddr_p);
void ipv6_push_frag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt,
			 u8 *proto);

int ipv6_skip_exthdr(const struct sk_buff *, int start, u8 *nexthdrp,
		     __be16 *frag_offp);

bool ipv6_ext_hdr(u8 nexthdr);

enum {
	IP6_FH_F_FRAG		= (1 << 0),
	IP6_FH_F_AUTH		= (1 << 1),
	IP6_FH_F_SKIP_RH	= (1 << 2),
};

/* find specified header and get offset to it */
int ipv6_find_hdr(const struct sk_buff *skb, unsigned int *offset, int target,
		  unsigned short *fragoff, int *fragflg);

int ipv6_find_tlv(struct sk_buff *skb, int offset, int type);

struct in6_addr *fl6_update_dst(struct flowi6 *fl6,
				const struct ipv6_txoptions *opt,
				struct in6_addr *orig);

/*
 *	socket options (ipv6_sockglue.c)
 */

int ipv6_setsockopt(struct sock *sk, int level, int optname,
		    char __user *optval, unsigned int optlen);
int ipv6_getsockopt(struct sock *sk, int level, int optname,
		    char __user *optval, int __user *optlen);
int compat_ipv6_setsockopt(struct sock *sk, int level, int optname,
			   char __user *optval, unsigned int optlen);
int compat_ipv6_getsockopt(struct sock *sk, int level, int optname,
			   char __user *optval, int __user *optlen);

int ip6_datagram_connect(struct sock *sk, struct sockaddr *addr, int addr_len);
int ip6_datagram_connect_v6_only(struct sock *sk, struct sockaddr *addr,
				 int addr_len);

int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len,
		    int *addr_len);
int ipv6_recv_rxpmtu(struct sock *sk, struct msghdr *msg, int len,
		     int *addr_len);
void ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err, __be16 port,
		     u32 info, u8 *payload);
void ipv6_local_error(struct sock *sk, int err, struct flowi6 *fl6, u32 info);
void ipv6_local_rxpmtu(struct sock *sk, struct flowi6 *fl6, u32 mtu);

int inet6_release(struct socket *sock);
int inet6_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len);
int inet6_getname(struct socket *sock, struct sockaddr *uaddr, int *uaddr_len,
		  int peer);
int inet6_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg);

int inet6_hash_connect(struct inet_timewait_death_row *death_row,
			      struct sock *sk);

/*
 * reassembly.c
 */
extern const struct proto_ops inet6_stream_ops;
extern const struct proto_ops inet6_dgram_ops;

struct group_source_req;
struct group_filter;

int ip6_mc_source(int add, int omode, struct sock *sk,
		  struct group_source_req *pgsr);
int ip6_mc_msfilter(struct sock *sk, struct group_filter *gsf);
int ip6_mc_msfget(struct sock *sk, struct group_filter *gsf,
		  struct group_filter __user *optval, int __user *optlen);

#ifdef CONFIG_PROC_FS
int ac6_proc_init(struct net *net);
void ac6_proc_exit(struct net *net);
int raw6_proc_init(void);
void raw6_proc_exit(void);
int tcp6_proc_init(struct net *net);
void tcp6_proc_exit(struct net *net);
int udp6_proc_init(struct net *net);
void udp6_proc_exit(struct net *net);
int udplite6_proc_init(void);
void udplite6_proc_exit(void);
int ipv6_misc_proc_init(void);
void ipv6_misc_proc_exit(void);
int snmp6_register_dev(struct inet6_dev *idev);
int snmp6_unregister_dev(struct inet6_dev *idev);

#else
static inline int ac6_proc_init(struct net *net) { return 0; }
static inline void ac6_proc_exit(struct net *net) { }
static inline int snmp6_register_dev(struct inet6_dev *idev) { return 0; }
static inline int snmp6_unregister_dev(struct inet6_dev *idev) { return 0; }
#endif

#ifdef CONFIG_SYSCTL
extern struct ctl_table ipv6_route_table_template[];

struct ctl_table *ipv6_icmp_sysctl_init(struct net *net);
struct ctl_table *ipv6_route_sysctl_init(struct net *net);
int ipv6_sysctl_register(void);
void ipv6_sysctl_unregister(void);
#endif

#endif /* _NET_IPV6_H */