xref: /openbmc/linux/include/net/ipv6.h (revision 79f08d9e)
1 /*
2  *	Linux INET6 implementation
3  *
4  *	Authors:
5  *	Pedro Roque		<roque@di.fc.ul.pt>
6  *
7  *	This program is free software; you can redistribute it and/or
8  *      modify it under the terms of the GNU General Public License
9  *      as published by the Free Software Foundation; either version
10  *      2 of the License, or (at your option) any later version.
11  */
12 
13 #ifndef _NET_IPV6_H
14 #define _NET_IPV6_H
15 
16 #include <linux/ipv6.h>
17 #include <linux/hardirq.h>
18 #include <linux/jhash.h>
19 #include <net/if_inet6.h>
20 #include <net/ndisc.h>
21 #include <net/flow.h>
22 #include <net/snmp.h>
23 
24 #define SIN6_LEN_RFC2133	24
25 
26 #define IPV6_MAXPLEN		65535
27 
28 /*
29  *	NextHeader field of IPv6 header
30  */
31 
32 #define NEXTHDR_HOP		0	/* Hop-by-hop option header. */
33 #define NEXTHDR_TCP		6	/* TCP segment. */
34 #define NEXTHDR_UDP		17	/* UDP message. */
35 #define NEXTHDR_IPV6		41	/* IPv6 in IPv6 */
36 #define NEXTHDR_ROUTING		43	/* Routing header. */
37 #define NEXTHDR_FRAGMENT	44	/* Fragmentation/reassembly header. */
38 #define NEXTHDR_GRE		47	/* GRE header. */
39 #define NEXTHDR_ESP		50	/* Encapsulating security payload. */
40 #define NEXTHDR_AUTH		51	/* Authentication header. */
41 #define NEXTHDR_ICMP		58	/* ICMP for IPv6. */
42 #define NEXTHDR_NONE		59	/* No next header */
43 #define NEXTHDR_DEST		60	/* Destination options header. */
44 #define NEXTHDR_SCTP		132	/* SCTP message. */
45 #define NEXTHDR_MOBILITY	135	/* Mobility header. */
46 
47 #define NEXTHDR_MAX		255
48 
49 
50 
51 #define IPV6_DEFAULT_HOPLIMIT   64
52 #define IPV6_DEFAULT_MCASTHOPS	1
53 
54 /*
55  *	Addr type
56  *
57  *	type	-	unicast | multicast
58  *	scope	-	local	| site	    | global
59  *	v4	-	compat
60  *	v4mapped
61  *	any
62  *	loopback
63  */
64 
65 #define IPV6_ADDR_ANY		0x0000U
66 
67 #define IPV6_ADDR_UNICAST      	0x0001U
68 #define IPV6_ADDR_MULTICAST    	0x0002U
69 
70 #define IPV6_ADDR_LOOPBACK	0x0010U
71 #define IPV6_ADDR_LINKLOCAL	0x0020U
72 #define IPV6_ADDR_SITELOCAL	0x0040U
73 
74 #define IPV6_ADDR_COMPATv4	0x0080U
75 
76 #define IPV6_ADDR_SCOPE_MASK	0x00f0U
77 
78 #define IPV6_ADDR_MAPPED	0x1000U
79 
80 /*
81  *	Addr scopes
82  */
83 #define IPV6_ADDR_MC_SCOPE(a)	\
84 	((a)->s6_addr[1] & 0x0f)	/* nonstandard */
85 #define __IPV6_ADDR_SCOPE_INVALID	-1
86 #define IPV6_ADDR_SCOPE_NODELOCAL	0x01
87 #define IPV6_ADDR_SCOPE_LINKLOCAL	0x02
88 #define IPV6_ADDR_SCOPE_SITELOCAL	0x05
89 #define IPV6_ADDR_SCOPE_ORGLOCAL	0x08
90 #define IPV6_ADDR_SCOPE_GLOBAL		0x0e
91 
92 /*
93  *	Addr flags
94  */
95 #define IPV6_ADDR_MC_FLAG_TRANSIENT(a)	\
96 	((a)->s6_addr[1] & 0x10)
97 #define IPV6_ADDR_MC_FLAG_PREFIX(a)	\
98 	((a)->s6_addr[1] & 0x20)
99 #define IPV6_ADDR_MC_FLAG_RENDEZVOUS(a)	\
100 	((a)->s6_addr[1] & 0x40)
101 
102 /*
103  *	fragmentation header
104  */
105 
106 struct frag_hdr {
107 	__u8	nexthdr;
108 	__u8	reserved;
109 	__be16	frag_off;
110 	__be32	identification;
111 };
112 
113 #define	IP6_MF	0x0001
114 
115 #include <net/sock.h>
116 
117 /* sysctls */
118 extern int sysctl_mld_max_msf;
119 
120 #define _DEVINC(net, statname, modifier, idev, field)			\
121 ({									\
122 	struct inet6_dev *_idev = (idev);				\
123 	if (likely(_idev != NULL))					\
124 		SNMP_INC_STATS##modifier((_idev)->stats.statname, (field)); \
125 	SNMP_INC_STATS##modifier((net)->mib.statname##_statistics, (field));\
126 })
127 
128 /* per device counters are atomic_long_t */
129 #define _DEVINCATOMIC(net, statname, modifier, idev, field)		\
130 ({									\
131 	struct inet6_dev *_idev = (idev);				\
132 	if (likely(_idev != NULL))					\
133 		SNMP_INC_STATS_ATOMIC_LONG((_idev)->stats.statname##dev, (field)); \
134 	SNMP_INC_STATS##modifier((net)->mib.statname##_statistics, (field));\
135 })
136 
137 /* per device and per net counters are atomic_long_t */
138 #define _DEVINC_ATOMIC_ATOMIC(net, statname, idev, field)		\
139 ({									\
140 	struct inet6_dev *_idev = (idev);				\
141 	if (likely(_idev != NULL))					\
142 		SNMP_INC_STATS_ATOMIC_LONG((_idev)->stats.statname##dev, (field)); \
143 	SNMP_INC_STATS_ATOMIC_LONG((net)->mib.statname##_statistics, (field));\
144 })
145 
146 #define _DEVADD(net, statname, modifier, idev, field, val)		\
147 ({									\
148 	struct inet6_dev *_idev = (idev);				\
149 	if (likely(_idev != NULL))					\
150 		SNMP_ADD_STATS##modifier((_idev)->stats.statname, (field), (val)); \
151 	SNMP_ADD_STATS##modifier((net)->mib.statname##_statistics, (field), (val));\
152 })
153 
154 #define _DEVUPD(net, statname, modifier, idev, field, val)		\
155 ({									\
156 	struct inet6_dev *_idev = (idev);				\
157 	if (likely(_idev != NULL))					\
158 		SNMP_UPD_PO_STATS##modifier((_idev)->stats.statname, field, (val)); \
159 	SNMP_UPD_PO_STATS##modifier((net)->mib.statname##_statistics, field, (val));\
160 })
161 
162 /* MIBs */
163 
164 #define IP6_INC_STATS(net, idev,field)		\
165 		_DEVINC(net, ipv6, 64, idev, field)
166 #define IP6_INC_STATS_BH(net, idev,field)	\
167 		_DEVINC(net, ipv6, 64_BH, idev, field)
168 #define IP6_ADD_STATS(net, idev,field,val)	\
169 		_DEVADD(net, ipv6, 64, idev, field, val)
170 #define IP6_ADD_STATS_BH(net, idev,field,val)	\
171 		_DEVADD(net, ipv6, 64_BH, idev, field, val)
172 #define IP6_UPD_PO_STATS(net, idev,field,val)   \
173 		_DEVUPD(net, ipv6, 64, idev, field, val)
174 #define IP6_UPD_PO_STATS_BH(net, idev,field,val)   \
175 		_DEVUPD(net, ipv6, 64_BH, idev, field, val)
176 #define ICMP6_INC_STATS(net, idev, field)	\
177 		_DEVINCATOMIC(net, icmpv6, , idev, field)
178 #define ICMP6_INC_STATS_BH(net, idev, field)	\
179 		_DEVINCATOMIC(net, icmpv6, _BH, idev, field)
180 
181 #define ICMP6MSGOUT_INC_STATS(net, idev, field)		\
182 	_DEVINC_ATOMIC_ATOMIC(net, icmpv6msg, idev, field +256)
183 #define ICMP6MSGOUT_INC_STATS_BH(net, idev, field)	\
184 	_DEVINC_ATOMIC_ATOMIC(net, icmpv6msg, idev, field +256)
185 #define ICMP6MSGIN_INC_STATS_BH(net, idev, field)	\
186 	_DEVINC_ATOMIC_ATOMIC(net, icmpv6msg, idev, field)
187 
188 struct ip6_ra_chain {
189 	struct ip6_ra_chain	*next;
190 	struct sock		*sk;
191 	int			sel;
192 	void			(*destructor)(struct sock *);
193 };
194 
195 extern struct ip6_ra_chain	*ip6_ra_chain;
196 extern rwlock_t ip6_ra_lock;
197 
198 /*
199    This structure is prepared by protocol, when parsing
200    ancillary data and passed to IPv6.
201  */
202 
203 struct ipv6_txoptions {
204 	/* Length of this structure */
205 	int			tot_len;
206 
207 	/* length of extension headers   */
208 
209 	__u16			opt_flen;	/* after fragment hdr */
210 	__u16			opt_nflen;	/* before fragment hdr */
211 
212 	struct ipv6_opt_hdr	*hopopt;
213 	struct ipv6_opt_hdr	*dst0opt;
214 	struct ipv6_rt_hdr	*srcrt;	/* Routing Header */
215 	struct ipv6_opt_hdr	*dst1opt;
216 
217 	/* Option buffer, as read by IPV6_PKTOPTIONS, starts here. */
218 };
219 
220 struct ip6_flowlabel {
221 	struct ip6_flowlabel __rcu *next;
222 	__be32			label;
223 	atomic_t		users;
224 	struct in6_addr		dst;
225 	struct ipv6_txoptions	*opt;
226 	unsigned long		linger;
227 	struct rcu_head		rcu;
228 	u8			share;
229 	union {
230 		struct pid *pid;
231 		kuid_t uid;
232 	} owner;
233 	unsigned long		lastuse;
234 	unsigned long		expires;
235 	struct net		*fl_net;
236 };
237 
238 #define IPV6_FLOWINFO_MASK	cpu_to_be32(0x0FFFFFFF)
239 #define IPV6_FLOWLABEL_MASK	cpu_to_be32(0x000FFFFF)
240 
241 struct ipv6_fl_socklist {
242 	struct ipv6_fl_socklist	__rcu	*next;
243 	struct ip6_flowlabel		*fl;
244 	struct rcu_head			rcu;
245 };
246 
247 struct ip6_flowlabel *fl6_sock_lookup(struct sock *sk, __be32 label);
248 struct ipv6_txoptions *fl6_merge_options(struct ipv6_txoptions *opt_space,
249 					 struct ip6_flowlabel *fl,
250 					 struct ipv6_txoptions *fopt);
251 void fl6_free_socklist(struct sock *sk);
252 int ipv6_flowlabel_opt(struct sock *sk, char __user *optval, int optlen);
253 int ipv6_flowlabel_opt_get(struct sock *sk, struct in6_flowlabel_req *freq);
254 int ip6_flowlabel_init(void);
255 void ip6_flowlabel_cleanup(void);
256 
257 static inline void fl6_sock_release(struct ip6_flowlabel *fl)
258 {
259 	if (fl)
260 		atomic_dec(&fl->users);
261 }
262 
263 void icmpv6_notify(struct sk_buff *skb, u8 type, u8 code, __be32 info);
264 
265 int icmpv6_push_pending_frames(struct sock *sk, struct flowi6 *fl6,
266 			       struct icmp6hdr *thdr, int len);
267 
268 struct dst_entry *icmpv6_route_lookup(struct net *net, struct sk_buff *skb,
269 				      struct sock *sk, struct flowi6 *fl6);
270 
271 int ip6_ra_control(struct sock *sk, int sel);
272 
273 int ipv6_parse_hopopts(struct sk_buff *skb);
274 
275 struct ipv6_txoptions *ipv6_dup_options(struct sock *sk,
276 					struct ipv6_txoptions *opt);
277 struct ipv6_txoptions *ipv6_renew_options(struct sock *sk,
278 					  struct ipv6_txoptions *opt,
279 					  int newtype,
280 					  struct ipv6_opt_hdr __user *newopt,
281 					  int newoptlen);
282 struct ipv6_txoptions *ipv6_fixup_options(struct ipv6_txoptions *opt_space,
283 					  struct ipv6_txoptions *opt);
284 
285 bool ipv6_opt_accepted(const struct sock *sk, const struct sk_buff *skb);
286 
287 static inline bool ipv6_accept_ra(struct inet6_dev *idev)
288 {
289 	/* If forwarding is enabled, RA are not accepted unless the special
290 	 * hybrid mode (accept_ra=2) is enabled.
291 	 */
292 	return idev->cnf.forwarding ? idev->cnf.accept_ra == 2 :
293 	    idev->cnf.accept_ra;
294 }
295 
296 #if IS_ENABLED(CONFIG_IPV6)
297 static inline int ip6_frag_nqueues(struct net *net)
298 {
299 	return net->ipv6.frags.nqueues;
300 }
301 
302 static inline int ip6_frag_mem(struct net *net)
303 {
304 	return sum_frag_mem_limit(&net->ipv6.frags);
305 }
306 #endif
307 
308 #define IPV6_FRAG_HIGH_THRESH	(4 * 1024*1024)	/* 4194304 */
309 #define IPV6_FRAG_LOW_THRESH	(3 * 1024*1024)	/* 3145728 */
310 #define IPV6_FRAG_TIMEOUT	(60 * HZ)	/* 60 seconds */
311 
312 int __ipv6_addr_type(const struct in6_addr *addr);
313 static inline int ipv6_addr_type(const struct in6_addr *addr)
314 {
315 	return __ipv6_addr_type(addr) & 0xffff;
316 }
317 
318 static inline int ipv6_addr_scope(const struct in6_addr *addr)
319 {
320 	return __ipv6_addr_type(addr) & IPV6_ADDR_SCOPE_MASK;
321 }
322 
323 static inline int __ipv6_addr_src_scope(int type)
324 {
325 	return (type == IPV6_ADDR_ANY) ? __IPV6_ADDR_SCOPE_INVALID : (type >> 16);
326 }
327 
328 static inline int ipv6_addr_src_scope(const struct in6_addr *addr)
329 {
330 	return __ipv6_addr_src_scope(__ipv6_addr_type(addr));
331 }
332 
333 static inline bool __ipv6_addr_needs_scope_id(int type)
334 {
335 	return type & IPV6_ADDR_LINKLOCAL ||
336 	       (type & IPV6_ADDR_MULTICAST &&
337 		(type & (IPV6_ADDR_LOOPBACK|IPV6_ADDR_LINKLOCAL)));
338 }
339 
340 static inline __u32 ipv6_iface_scope_id(const struct in6_addr *addr, int iface)
341 {
342 	return __ipv6_addr_needs_scope_id(__ipv6_addr_type(addr)) ? iface : 0;
343 }
344 
345 static inline int ipv6_addr_cmp(const struct in6_addr *a1, const struct in6_addr *a2)
346 {
347 	return memcmp(a1, a2, sizeof(struct in6_addr));
348 }
349 
350 static inline bool
351 ipv6_masked_addr_cmp(const struct in6_addr *a1, const struct in6_addr *m,
352 		     const struct in6_addr *a2)
353 {
354 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
355 	const unsigned long *ul1 = (const unsigned long *)a1;
356 	const unsigned long *ulm = (const unsigned long *)m;
357 	const unsigned long *ul2 = (const unsigned long *)a2;
358 
359 	return !!(((ul1[0] ^ ul2[0]) & ulm[0]) |
360 		  ((ul1[1] ^ ul2[1]) & ulm[1]));
361 #else
362 	return !!(((a1->s6_addr32[0] ^ a2->s6_addr32[0]) & m->s6_addr32[0]) |
363 		  ((a1->s6_addr32[1] ^ a2->s6_addr32[1]) & m->s6_addr32[1]) |
364 		  ((a1->s6_addr32[2] ^ a2->s6_addr32[2]) & m->s6_addr32[2]) |
365 		  ((a1->s6_addr32[3] ^ a2->s6_addr32[3]) & m->s6_addr32[3]));
366 #endif
367 }
368 
369 static inline void ipv6_addr_prefix(struct in6_addr *pfx,
370 				    const struct in6_addr *addr,
371 				    int plen)
372 {
373 	/* caller must guarantee 0 <= plen <= 128 */
374 	int o = plen >> 3,
375 	    b = plen & 0x7;
376 
377 	memset(pfx->s6_addr, 0, sizeof(pfx->s6_addr));
378 	memcpy(pfx->s6_addr, addr, o);
379 	if (b != 0)
380 		pfx->s6_addr[o] = addr->s6_addr[o] & (0xff00 >> b);
381 }
382 
383 static inline void __ipv6_addr_set_half(__be32 *addr,
384 					__be32 wh, __be32 wl)
385 {
386 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
387 #if defined(__BIG_ENDIAN)
388 	if (__builtin_constant_p(wh) && __builtin_constant_p(wl)) {
389 		*(__force u64 *)addr = ((__force u64)(wh) << 32 | (__force u64)(wl));
390 		return;
391 	}
392 #elif defined(__LITTLE_ENDIAN)
393 	if (__builtin_constant_p(wl) && __builtin_constant_p(wh)) {
394 		*(__force u64 *)addr = ((__force u64)(wl) << 32 | (__force u64)(wh));
395 		return;
396 	}
397 #endif
398 #endif
399 	addr[0] = wh;
400 	addr[1] = wl;
401 }
402 
403 static inline void ipv6_addr_set(struct in6_addr *addr,
404 				     __be32 w1, __be32 w2,
405 				     __be32 w3, __be32 w4)
406 {
407 	__ipv6_addr_set_half(&addr->s6_addr32[0], w1, w2);
408 	__ipv6_addr_set_half(&addr->s6_addr32[2], w3, w4);
409 }
410 
411 static inline bool ipv6_addr_equal(const struct in6_addr *a1,
412 				   const struct in6_addr *a2)
413 {
414 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
415 	const unsigned long *ul1 = (const unsigned long *)a1;
416 	const unsigned long *ul2 = (const unsigned long *)a2;
417 
418 	return ((ul1[0] ^ ul2[0]) | (ul1[1] ^ ul2[1])) == 0UL;
419 #else
420 	return ((a1->s6_addr32[0] ^ a2->s6_addr32[0]) |
421 		(a1->s6_addr32[1] ^ a2->s6_addr32[1]) |
422 		(a1->s6_addr32[2] ^ a2->s6_addr32[2]) |
423 		(a1->s6_addr32[3] ^ a2->s6_addr32[3])) == 0;
424 #endif
425 }
426 
427 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
428 static inline bool __ipv6_prefix_equal64_half(const __be64 *a1,
429 					      const __be64 *a2,
430 					      unsigned int len)
431 {
432 	if (len && ((*a1 ^ *a2) & cpu_to_be64((~0UL) << (64 - len))))
433 		return false;
434 	return true;
435 }
436 
437 static inline bool ipv6_prefix_equal(const struct in6_addr *addr1,
438 				     const struct in6_addr *addr2,
439 				     unsigned int prefixlen)
440 {
441 	const __be64 *a1 = (const __be64 *)addr1;
442 	const __be64 *a2 = (const __be64 *)addr2;
443 
444 	if (prefixlen >= 64) {
445 		if (a1[0] ^ a2[0])
446 			return false;
447 		return __ipv6_prefix_equal64_half(a1 + 1, a2 + 1, prefixlen - 64);
448 	}
449 	return __ipv6_prefix_equal64_half(a1, a2, prefixlen);
450 }
451 #else
452 static inline bool ipv6_prefix_equal(const struct in6_addr *addr1,
453 				     const struct in6_addr *addr2,
454 				     unsigned int prefixlen)
455 {
456 	const __be32 *a1 = addr1->s6_addr32;
457 	const __be32 *a2 = addr2->s6_addr32;
458 	unsigned int pdw, pbi;
459 
460 	/* check complete u32 in prefix */
461 	pdw = prefixlen >> 5;
462 	if (pdw && memcmp(a1, a2, pdw << 2))
463 		return false;
464 
465 	/* check incomplete u32 in prefix */
466 	pbi = prefixlen & 0x1f;
467 	if (pbi && ((a1[pdw] ^ a2[pdw]) & htonl((0xffffffff) << (32 - pbi))))
468 		return false;
469 
470 	return true;
471 }
472 #endif
473 
474 struct inet_frag_queue;
475 
476 enum ip6_defrag_users {
477 	IP6_DEFRAG_LOCAL_DELIVER,
478 	IP6_DEFRAG_CONNTRACK_IN,
479 	__IP6_DEFRAG_CONNTRACK_IN	= IP6_DEFRAG_CONNTRACK_IN + USHRT_MAX,
480 	IP6_DEFRAG_CONNTRACK_OUT,
481 	__IP6_DEFRAG_CONNTRACK_OUT	= IP6_DEFRAG_CONNTRACK_OUT + USHRT_MAX,
482 	IP6_DEFRAG_CONNTRACK_BRIDGE_IN,
483 	__IP6_DEFRAG_CONNTRACK_BRIDGE_IN = IP6_DEFRAG_CONNTRACK_BRIDGE_IN + USHRT_MAX,
484 };
485 
486 struct ip6_create_arg {
487 	__be32 id;
488 	u32 user;
489 	const struct in6_addr *src;
490 	const struct in6_addr *dst;
491 	u8 ecn;
492 };
493 
494 void ip6_frag_init(struct inet_frag_queue *q, void *a);
495 bool ip6_frag_match(struct inet_frag_queue *q, void *a);
496 
497 /*
498  *	Equivalent of ipv4 struct ip
499  */
500 struct frag_queue {
501 	struct inet_frag_queue	q;
502 
503 	__be32			id;		/* fragment id		*/
504 	u32			user;
505 	struct in6_addr		saddr;
506 	struct in6_addr		daddr;
507 
508 	int			iif;
509 	unsigned int		csum;
510 	__u16			nhoffset;
511 	u8			ecn;
512 };
513 
514 void ip6_expire_frag_queue(struct net *net, struct frag_queue *fq,
515 			   struct inet_frags *frags);
516 
517 static inline bool ipv6_addr_any(const struct in6_addr *a)
518 {
519 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
520 	const unsigned long *ul = (const unsigned long *)a;
521 
522 	return (ul[0] | ul[1]) == 0UL;
523 #else
524 	return (a->s6_addr32[0] | a->s6_addr32[1] |
525 		a->s6_addr32[2] | a->s6_addr32[3]) == 0;
526 #endif
527 }
528 
529 static inline u32 ipv6_addr_hash(const struct in6_addr *a)
530 {
531 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
532 	const unsigned long *ul = (const unsigned long *)a;
533 	unsigned long x = ul[0] ^ ul[1];
534 
535 	return (u32)(x ^ (x >> 32));
536 #else
537 	return (__force u32)(a->s6_addr32[0] ^ a->s6_addr32[1] ^
538 			     a->s6_addr32[2] ^ a->s6_addr32[3]);
539 #endif
540 }
541 
542 /* more secured version of ipv6_addr_hash() */
543 static inline u32 __ipv6_addr_jhash(const struct in6_addr *a, const u32 initval)
544 {
545 	u32 v = (__force u32)a->s6_addr32[0] ^ (__force u32)a->s6_addr32[1];
546 
547 	return jhash_3words(v,
548 			    (__force u32)a->s6_addr32[2],
549 			    (__force u32)a->s6_addr32[3],
550 			    initval);
551 }
552 
553 static inline bool ipv6_addr_loopback(const struct in6_addr *a)
554 {
555 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
556 	const unsigned long *ul = (const unsigned long *)a;
557 
558 	return (ul[0] | (ul[1] ^ cpu_to_be64(1))) == 0UL;
559 #else
560 	return (a->s6_addr32[0] | a->s6_addr32[1] |
561 		a->s6_addr32[2] | (a->s6_addr32[3] ^ htonl(1))) == 0;
562 #endif
563 }
564 
565 static inline bool ipv6_addr_v4mapped(const struct in6_addr *a)
566 {
567 	return (
568 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
569 		*(__be64 *)a |
570 #else
571 		(a->s6_addr32[0] | a->s6_addr32[1]) |
572 #endif
573 		(a->s6_addr32[2] ^ htonl(0x0000ffff))) == 0UL;
574 }
575 
576 /*
577  * Check for a RFC 4843 ORCHID address
578  * (Overlay Routable Cryptographic Hash Identifiers)
579  */
580 static inline bool ipv6_addr_orchid(const struct in6_addr *a)
581 {
582 	return (a->s6_addr32[0] & htonl(0xfffffff0)) == htonl(0x20010010);
583 }
584 
585 static inline void ipv6_addr_set_v4mapped(const __be32 addr,
586 					  struct in6_addr *v4mapped)
587 {
588 	ipv6_addr_set(v4mapped,
589 			0, 0,
590 			htonl(0x0000FFFF),
591 			addr);
592 }
593 
594 /*
595  * find the first different bit between two addresses
596  * length of address must be a multiple of 32bits
597  */
598 static inline int __ipv6_addr_diff32(const void *token1, const void *token2, int addrlen)
599 {
600 	const __be32 *a1 = token1, *a2 = token2;
601 	int i;
602 
603 	addrlen >>= 2;
604 
605 	for (i = 0; i < addrlen; i++) {
606 		__be32 xb = a1[i] ^ a2[i];
607 		if (xb)
608 			return i * 32 + 31 - __fls(ntohl(xb));
609 	}
610 
611 	/*
612 	 *	we should *never* get to this point since that
613 	 *	would mean the addrs are equal
614 	 *
615 	 *	However, we do get to it 8) And exacly, when
616 	 *	addresses are equal 8)
617 	 *
618 	 *	ip route add 1111::/128 via ...
619 	 *	ip route add 1111::/64 via ...
620 	 *	and we are here.
621 	 *
622 	 *	Ideally, this function should stop comparison
623 	 *	at prefix length. It does not, but it is still OK,
624 	 *	if returned value is greater than prefix length.
625 	 *					--ANK (980803)
626 	 */
627 	return addrlen << 5;
628 }
629 
630 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
631 static inline int __ipv6_addr_diff64(const void *token1, const void *token2, int addrlen)
632 {
633 	const __be64 *a1 = token1, *a2 = token2;
634 	int i;
635 
636 	addrlen >>= 3;
637 
638 	for (i = 0; i < addrlen; i++) {
639 		__be64 xb = a1[i] ^ a2[i];
640 		if (xb)
641 			return i * 64 + 63 - __fls(be64_to_cpu(xb));
642 	}
643 
644 	return addrlen << 6;
645 }
646 #endif
647 
648 static inline int __ipv6_addr_diff(const void *token1, const void *token2, int addrlen)
649 {
650 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
651 	if (__builtin_constant_p(addrlen) && !(addrlen & 7))
652 		return __ipv6_addr_diff64(token1, token2, addrlen);
653 #endif
654 	return __ipv6_addr_diff32(token1, token2, addrlen);
655 }
656 
657 static inline int ipv6_addr_diff(const struct in6_addr *a1, const struct in6_addr *a2)
658 {
659 	return __ipv6_addr_diff(a1, a2, sizeof(struct in6_addr));
660 }
661 
662 void ipv6_select_ident(struct frag_hdr *fhdr, struct rt6_info *rt);
663 
664 int ip6_dst_hoplimit(struct dst_entry *dst);
665 
666 /*
667  *	Header manipulation
668  */
669 static inline void ip6_flow_hdr(struct ipv6hdr *hdr, unsigned int tclass,
670 				__be32 flowlabel)
671 {
672 	*(__be32 *)hdr = htonl(0x60000000 | (tclass << 20)) | flowlabel;
673 }
674 
675 static inline __be32 ip6_flowinfo(const struct ipv6hdr *hdr)
676 {
677 	return *(__be32 *)hdr & IPV6_FLOWINFO_MASK;
678 }
679 
680 /*
681  *	Prototypes exported by ipv6
682  */
683 
684 /*
685  *	rcv function (called from netdevice level)
686  */
687 
688 int ipv6_rcv(struct sk_buff *skb, struct net_device *dev,
689 	     struct packet_type *pt, struct net_device *orig_dev);
690 
691 int ip6_rcv_finish(struct sk_buff *skb);
692 
693 /*
694  *	upper-layer output functions
695  */
696 int ip6_xmit(struct sock *sk, struct sk_buff *skb, struct flowi6 *fl6,
697 	     struct ipv6_txoptions *opt, int tclass);
698 
699 int ip6_find_1stfragopt(struct sk_buff *skb, u8 **nexthdr);
700 
701 int ip6_append_data(struct sock *sk,
702 		    int getfrag(void *from, char *to, int offset, int len,
703 				int odd, struct sk_buff *skb),
704 		    void *from, int length, int transhdrlen, int hlimit,
705 		    int tclass, struct ipv6_txoptions *opt, struct flowi6 *fl6,
706 		    struct rt6_info *rt, unsigned int flags, int dontfrag);
707 
708 int ip6_push_pending_frames(struct sock *sk);
709 
710 void ip6_flush_pending_frames(struct sock *sk);
711 
712 int ip6_dst_lookup(struct sock *sk, struct dst_entry **dst, struct flowi6 *fl6);
713 struct dst_entry *ip6_dst_lookup_flow(struct sock *sk, struct flowi6 *fl6,
714 				      const struct in6_addr *final_dst,
715 				      bool can_sleep);
716 struct dst_entry *ip6_sk_dst_lookup_flow(struct sock *sk, struct flowi6 *fl6,
717 					 const struct in6_addr *final_dst,
718 					 bool can_sleep);
719 struct dst_entry *ip6_blackhole_route(struct net *net,
720 				      struct dst_entry *orig_dst);
721 
722 /*
723  *	skb processing functions
724  */
725 
726 int ip6_output(struct sk_buff *skb);
727 int ip6_forward(struct sk_buff *skb);
728 int ip6_input(struct sk_buff *skb);
729 int ip6_mc_input(struct sk_buff *skb);
730 
731 int __ip6_local_out(struct sk_buff *skb);
732 int ip6_local_out(struct sk_buff *skb);
733 
734 /*
735  *	Extension header (options) processing
736  */
737 
738 void ipv6_push_nfrag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt,
739 			  u8 *proto, struct in6_addr **daddr_p);
740 void ipv6_push_frag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt,
741 			 u8 *proto);
742 
743 int ipv6_skip_exthdr(const struct sk_buff *, int start, u8 *nexthdrp,
744 		     __be16 *frag_offp);
745 
746 bool ipv6_ext_hdr(u8 nexthdr);
747 
748 enum {
749 	IP6_FH_F_FRAG		= (1 << 0),
750 	IP6_FH_F_AUTH		= (1 << 1),
751 	IP6_FH_F_SKIP_RH	= (1 << 2),
752 };
753 
754 /* find specified header and get offset to it */
755 int ipv6_find_hdr(const struct sk_buff *skb, unsigned int *offset, int target,
756 		  unsigned short *fragoff, int *fragflg);
757 
758 int ipv6_find_tlv(struct sk_buff *skb, int offset, int type);
759 
760 struct in6_addr *fl6_update_dst(struct flowi6 *fl6,
761 				const struct ipv6_txoptions *opt,
762 				struct in6_addr *orig);
763 
764 /*
765  *	socket options (ipv6_sockglue.c)
766  */
767 
768 int ipv6_setsockopt(struct sock *sk, int level, int optname,
769 		    char __user *optval, unsigned int optlen);
770 int ipv6_getsockopt(struct sock *sk, int level, int optname,
771 		    char __user *optval, int __user *optlen);
772 int compat_ipv6_setsockopt(struct sock *sk, int level, int optname,
773 			   char __user *optval, unsigned int optlen);
774 int compat_ipv6_getsockopt(struct sock *sk, int level, int optname,
775 			   char __user *optval, int __user *optlen);
776 
777 int ip6_datagram_connect(struct sock *sk, struct sockaddr *addr, int addr_len);
778 
779 int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len);
780 int ipv6_recv_rxpmtu(struct sock *sk, struct msghdr *msg, int len);
781 void ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err, __be16 port,
782 		     u32 info, u8 *payload);
783 void ipv6_local_error(struct sock *sk, int err, struct flowi6 *fl6, u32 info);
784 void ipv6_local_rxpmtu(struct sock *sk, struct flowi6 *fl6, u32 mtu);
785 
786 int inet6_release(struct socket *sock);
787 int inet6_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len);
788 int inet6_getname(struct socket *sock, struct sockaddr *uaddr, int *uaddr_len,
789 		  int peer);
790 int inet6_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg);
791 
792 int inet6_hash_connect(struct inet_timewait_death_row *death_row,
793 			      struct sock *sk);
794 
795 /*
796  * reassembly.c
797  */
798 extern const struct proto_ops inet6_stream_ops;
799 extern const struct proto_ops inet6_dgram_ops;
800 
801 struct group_source_req;
802 struct group_filter;
803 
804 int ip6_mc_source(int add, int omode, struct sock *sk,
805 		  struct group_source_req *pgsr);
806 int ip6_mc_msfilter(struct sock *sk, struct group_filter *gsf);
807 int ip6_mc_msfget(struct sock *sk, struct group_filter *gsf,
808 		  struct group_filter __user *optval, int __user *optlen);
809 
810 #ifdef CONFIG_PROC_FS
811 int ac6_proc_init(struct net *net);
812 void ac6_proc_exit(struct net *net);
813 int raw6_proc_init(void);
814 void raw6_proc_exit(void);
815 int tcp6_proc_init(struct net *net);
816 void tcp6_proc_exit(struct net *net);
817 int udp6_proc_init(struct net *net);
818 void udp6_proc_exit(struct net *net);
819 int udplite6_proc_init(void);
820 void udplite6_proc_exit(void);
821 int ipv6_misc_proc_init(void);
822 void ipv6_misc_proc_exit(void);
823 int snmp6_register_dev(struct inet6_dev *idev);
824 int snmp6_unregister_dev(struct inet6_dev *idev);
825 
826 #else
827 static inline int ac6_proc_init(struct net *net) { return 0; }
828 static inline void ac6_proc_exit(struct net *net) { }
829 static inline int snmp6_register_dev(struct inet6_dev *idev) { return 0; }
830 static inline int snmp6_unregister_dev(struct inet6_dev *idev) { return 0; }
831 #endif
832 
833 #ifdef CONFIG_SYSCTL
834 extern struct ctl_table ipv6_route_table_template[];
835 extern struct ctl_table ipv6_icmp_table_template[];
836 
837 struct ctl_table *ipv6_icmp_sysctl_init(struct net *net);
838 struct ctl_table *ipv6_route_sysctl_init(struct net *net);
839 int ipv6_sysctl_register(void);
840 void ipv6_sysctl_unregister(void);
841 #endif
842 
843 #endif /* _NET_IPV6_H */
844