xref: /openbmc/linux/include/net/ipv6.h (revision 5d0e4d78)
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 <linux/refcount.h>
20 #include <net/if_inet6.h>
21 #include <net/ndisc.h>
22 #include <net/flow.h>
23 #include <net/flow_dissector.h>
24 #include <net/snmp.h>
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_TCP		6	/* TCP segment. */
36 #define NEXTHDR_UDP		17	/* UDP message. */
37 #define NEXTHDR_IPV6		41	/* IPv6 in IPv6 */
38 #define NEXTHDR_ROUTING		43	/* Routing header. */
39 #define NEXTHDR_FRAGMENT	44	/* Fragmentation/reassembly header. */
40 #define NEXTHDR_GRE		47	/* GRE header. */
41 #define NEXTHDR_ESP		50	/* Encapsulating security payload. */
42 #define NEXTHDR_AUTH		51	/* Authentication header. */
43 #define NEXTHDR_ICMP		58	/* ICMP for IPv6. */
44 #define NEXTHDR_NONE		59	/* No next header */
45 #define NEXTHDR_DEST		60	/* Destination options header. */
46 #define NEXTHDR_SCTP		132	/* SCTP message. */
47 #define NEXTHDR_MOBILITY	135	/* Mobility header. */
48 
49 #define NEXTHDR_MAX		255
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 #define	IP6_OFFSET	0xFFF8
115 
116 #define IP6_REPLY_MARK(net, mark) \
117 	((net)->ipv6.sysctl.fwmark_reflect ? (mark) : 0)
118 
119 #include <net/sock.h>
120 
121 /* sysctls */
122 extern int sysctl_mld_max_msf;
123 extern int sysctl_mld_qrv;
124 
125 #define _DEVINC(net, statname, mod, idev, field)			\
126 ({									\
127 	struct inet6_dev *_idev = (idev);				\
128 	if (likely(_idev != NULL))					\
129 		mod##SNMP_INC_STATS64((_idev)->stats.statname, (field));\
130 	mod##SNMP_INC_STATS64((net)->mib.statname##_statistics, (field));\
131 })
132 
133 /* per device counters are atomic_long_t */
134 #define _DEVINCATOMIC(net, statname, mod, idev, field)			\
135 ({									\
136 	struct inet6_dev *_idev = (idev);				\
137 	if (likely(_idev != NULL))					\
138 		SNMP_INC_STATS_ATOMIC_LONG((_idev)->stats.statname##dev, (field)); \
139 	mod##SNMP_INC_STATS((net)->mib.statname##_statistics, (field));\
140 })
141 
142 /* per device and per net counters are atomic_long_t */
143 #define _DEVINC_ATOMIC_ATOMIC(net, statname, idev, field)		\
144 ({									\
145 	struct inet6_dev *_idev = (idev);				\
146 	if (likely(_idev != NULL))					\
147 		SNMP_INC_STATS_ATOMIC_LONG((_idev)->stats.statname##dev, (field)); \
148 	SNMP_INC_STATS_ATOMIC_LONG((net)->mib.statname##_statistics, (field));\
149 })
150 
151 #define _DEVADD(net, statname, mod, idev, field, val)			\
152 ({									\
153 	struct inet6_dev *_idev = (idev);				\
154 	if (likely(_idev != NULL))					\
155 		mod##SNMP_ADD_STATS((_idev)->stats.statname, (field), (val)); \
156 	mod##SNMP_ADD_STATS((net)->mib.statname##_statistics, (field), (val));\
157 })
158 
159 #define _DEVUPD(net, statname, mod, idev, field, val)			\
160 ({									\
161 	struct inet6_dev *_idev = (idev);				\
162 	if (likely(_idev != NULL))					\
163 		mod##SNMP_UPD_PO_STATS((_idev)->stats.statname, field, (val)); \
164 	mod##SNMP_UPD_PO_STATS((net)->mib.statname##_statistics, field, (val));\
165 })
166 
167 /* MIBs */
168 
169 #define IP6_INC_STATS(net, idev,field)		\
170 		_DEVINC(net, ipv6, , idev, field)
171 #define __IP6_INC_STATS(net, idev,field)	\
172 		_DEVINC(net, ipv6, __, idev, field)
173 #define IP6_ADD_STATS(net, idev,field,val)	\
174 		_DEVADD(net, ipv6, , idev, field, val)
175 #define __IP6_ADD_STATS(net, idev,field,val)	\
176 		_DEVADD(net, ipv6, __, idev, field, val)
177 #define IP6_UPD_PO_STATS(net, idev,field,val)   \
178 		_DEVUPD(net, ipv6, , idev, field, val)
179 #define __IP6_UPD_PO_STATS(net, idev,field,val)   \
180 		_DEVUPD(net, ipv6, __, idev, field, val)
181 #define ICMP6_INC_STATS(net, idev, field)	\
182 		_DEVINCATOMIC(net, icmpv6, , idev, field)
183 #define __ICMP6_INC_STATS(net, idev, field)	\
184 		_DEVINCATOMIC(net, icmpv6, __, idev, field)
185 
186 #define ICMP6MSGOUT_INC_STATS(net, idev, field)		\
187 	_DEVINC_ATOMIC_ATOMIC(net, icmpv6msg, idev, field +256)
188 #define ICMP6MSGIN_INC_STATS(net, idev, field)	\
189 	_DEVINC_ATOMIC_ATOMIC(net, icmpv6msg, idev, field)
190 
191 struct ip6_ra_chain {
192 	struct ip6_ra_chain	*next;
193 	struct sock		*sk;
194 	int			sel;
195 	void			(*destructor)(struct sock *);
196 };
197 
198 extern struct ip6_ra_chain	*ip6_ra_chain;
199 extern rwlock_t ip6_ra_lock;
200 
201 /*
202    This structure is prepared by protocol, when parsing
203    ancillary data and passed to IPv6.
204  */
205 
206 struct ipv6_txoptions {
207 	refcount_t		refcnt;
208 	/* Length of this structure */
209 	int			tot_len;
210 
211 	/* length of extension headers   */
212 
213 	__u16			opt_flen;	/* after fragment hdr */
214 	__u16			opt_nflen;	/* before fragment hdr */
215 
216 	struct ipv6_opt_hdr	*hopopt;
217 	struct ipv6_opt_hdr	*dst0opt;
218 	struct ipv6_rt_hdr	*srcrt;	/* Routing Header */
219 	struct ipv6_opt_hdr	*dst1opt;
220 	struct rcu_head		rcu;
221 	/* Option buffer, as read by IPV6_PKTOPTIONS, starts here. */
222 };
223 
224 struct ip6_flowlabel {
225 	struct ip6_flowlabel __rcu *next;
226 	__be32			label;
227 	atomic_t		users;
228 	struct in6_addr		dst;
229 	struct ipv6_txoptions	*opt;
230 	unsigned long		linger;
231 	struct rcu_head		rcu;
232 	u8			share;
233 	union {
234 		struct pid *pid;
235 		kuid_t uid;
236 	} owner;
237 	unsigned long		lastuse;
238 	unsigned long		expires;
239 	struct net		*fl_net;
240 };
241 
242 #define IPV6_FLOWINFO_MASK		cpu_to_be32(0x0FFFFFFF)
243 #define IPV6_FLOWLABEL_MASK		cpu_to_be32(0x000FFFFF)
244 #define IPV6_FLOWLABEL_STATELESS_FLAG	cpu_to_be32(0x00080000)
245 
246 #define IPV6_TCLASS_MASK (IPV6_FLOWINFO_MASK & ~IPV6_FLOWLABEL_MASK)
247 #define IPV6_TCLASS_SHIFT	20
248 
249 struct ipv6_fl_socklist {
250 	struct ipv6_fl_socklist	__rcu	*next;
251 	struct ip6_flowlabel		*fl;
252 	struct rcu_head			rcu;
253 };
254 
255 struct ipcm6_cookie {
256 	__s16 hlimit;
257 	__s16 tclass;
258 	__s8  dontfrag;
259 	struct ipv6_txoptions *opt;
260 };
261 
262 static inline struct ipv6_txoptions *txopt_get(const struct ipv6_pinfo *np)
263 {
264 	struct ipv6_txoptions *opt;
265 
266 	rcu_read_lock();
267 	opt = rcu_dereference(np->opt);
268 	if (opt) {
269 		if (!refcount_inc_not_zero(&opt->refcnt))
270 			opt = NULL;
271 		else
272 			opt = rcu_pointer_handoff(opt);
273 	}
274 	rcu_read_unlock();
275 	return opt;
276 }
277 
278 static inline void txopt_put(struct ipv6_txoptions *opt)
279 {
280 	if (opt && refcount_dec_and_test(&opt->refcnt))
281 		kfree_rcu(opt, rcu);
282 }
283 
284 struct ip6_flowlabel *fl6_sock_lookup(struct sock *sk, __be32 label);
285 struct ipv6_txoptions *fl6_merge_options(struct ipv6_txoptions *opt_space,
286 					 struct ip6_flowlabel *fl,
287 					 struct ipv6_txoptions *fopt);
288 void fl6_free_socklist(struct sock *sk);
289 int ipv6_flowlabel_opt(struct sock *sk, char __user *optval, int optlen);
290 int ipv6_flowlabel_opt_get(struct sock *sk, struct in6_flowlabel_req *freq,
291 			   int flags);
292 int ip6_flowlabel_init(void);
293 void ip6_flowlabel_cleanup(void);
294 
295 static inline void fl6_sock_release(struct ip6_flowlabel *fl)
296 {
297 	if (fl)
298 		atomic_dec(&fl->users);
299 }
300 
301 void icmpv6_notify(struct sk_buff *skb, u8 type, u8 code, __be32 info);
302 
303 int icmpv6_push_pending_frames(struct sock *sk, struct flowi6 *fl6,
304 			       struct icmp6hdr *thdr, int len);
305 
306 int ip6_ra_control(struct sock *sk, int sel);
307 
308 int ipv6_parse_hopopts(struct sk_buff *skb);
309 
310 struct ipv6_txoptions *ipv6_dup_options(struct sock *sk,
311 					struct ipv6_txoptions *opt);
312 struct ipv6_txoptions *ipv6_renew_options(struct sock *sk,
313 					  struct ipv6_txoptions *opt,
314 					  int newtype,
315 					  struct ipv6_opt_hdr __user *newopt,
316 					  int newoptlen);
317 struct ipv6_txoptions *
318 ipv6_renew_options_kern(struct sock *sk,
319 			struct ipv6_txoptions *opt,
320 			int newtype,
321 			struct ipv6_opt_hdr *newopt,
322 			int newoptlen);
323 struct ipv6_txoptions *ipv6_fixup_options(struct ipv6_txoptions *opt_space,
324 					  struct ipv6_txoptions *opt);
325 
326 bool ipv6_opt_accepted(const struct sock *sk, const struct sk_buff *skb,
327 		       const struct inet6_skb_parm *opt);
328 struct ipv6_txoptions *ipv6_update_options(struct sock *sk,
329 					   struct ipv6_txoptions *opt);
330 
331 static inline bool ipv6_accept_ra(struct inet6_dev *idev)
332 {
333 	/* If forwarding is enabled, RA are not accepted unless the special
334 	 * hybrid mode (accept_ra=2) is enabled.
335 	 */
336 	return idev->cnf.forwarding ? idev->cnf.accept_ra == 2 :
337 	    idev->cnf.accept_ra;
338 }
339 
340 #if IS_ENABLED(CONFIG_IPV6)
341 static inline int ip6_frag_mem(struct net *net)
342 {
343 	return sum_frag_mem_limit(&net->ipv6.frags);
344 }
345 #endif
346 
347 #define IPV6_FRAG_HIGH_THRESH	(4 * 1024*1024)	/* 4194304 */
348 #define IPV6_FRAG_LOW_THRESH	(3 * 1024*1024)	/* 3145728 */
349 #define IPV6_FRAG_TIMEOUT	(60 * HZ)	/* 60 seconds */
350 
351 int __ipv6_addr_type(const struct in6_addr *addr);
352 static inline int ipv6_addr_type(const struct in6_addr *addr)
353 {
354 	return __ipv6_addr_type(addr) & 0xffff;
355 }
356 
357 static inline int ipv6_addr_scope(const struct in6_addr *addr)
358 {
359 	return __ipv6_addr_type(addr) & IPV6_ADDR_SCOPE_MASK;
360 }
361 
362 static inline int __ipv6_addr_src_scope(int type)
363 {
364 	return (type == IPV6_ADDR_ANY) ? __IPV6_ADDR_SCOPE_INVALID : (type >> 16);
365 }
366 
367 static inline int ipv6_addr_src_scope(const struct in6_addr *addr)
368 {
369 	return __ipv6_addr_src_scope(__ipv6_addr_type(addr));
370 }
371 
372 static inline bool __ipv6_addr_needs_scope_id(int type)
373 {
374 	return type & IPV6_ADDR_LINKLOCAL ||
375 	       (type & IPV6_ADDR_MULTICAST &&
376 		(type & (IPV6_ADDR_LOOPBACK|IPV6_ADDR_LINKLOCAL)));
377 }
378 
379 static inline __u32 ipv6_iface_scope_id(const struct in6_addr *addr, int iface)
380 {
381 	return __ipv6_addr_needs_scope_id(__ipv6_addr_type(addr)) ? iface : 0;
382 }
383 
384 static inline int ipv6_addr_cmp(const struct in6_addr *a1, const struct in6_addr *a2)
385 {
386 	return memcmp(a1, a2, sizeof(struct in6_addr));
387 }
388 
389 static inline bool
390 ipv6_masked_addr_cmp(const struct in6_addr *a1, const struct in6_addr *m,
391 		     const struct in6_addr *a2)
392 {
393 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
394 	const unsigned long *ul1 = (const unsigned long *)a1;
395 	const unsigned long *ulm = (const unsigned long *)m;
396 	const unsigned long *ul2 = (const unsigned long *)a2;
397 
398 	return !!(((ul1[0] ^ ul2[0]) & ulm[0]) |
399 		  ((ul1[1] ^ ul2[1]) & ulm[1]));
400 #else
401 	return !!(((a1->s6_addr32[0] ^ a2->s6_addr32[0]) & m->s6_addr32[0]) |
402 		  ((a1->s6_addr32[1] ^ a2->s6_addr32[1]) & m->s6_addr32[1]) |
403 		  ((a1->s6_addr32[2] ^ a2->s6_addr32[2]) & m->s6_addr32[2]) |
404 		  ((a1->s6_addr32[3] ^ a2->s6_addr32[3]) & m->s6_addr32[3]));
405 #endif
406 }
407 
408 static inline void ipv6_addr_prefix(struct in6_addr *pfx,
409 				    const struct in6_addr *addr,
410 				    int plen)
411 {
412 	/* caller must guarantee 0 <= plen <= 128 */
413 	int o = plen >> 3,
414 	    b = plen & 0x7;
415 
416 	memset(pfx->s6_addr, 0, sizeof(pfx->s6_addr));
417 	memcpy(pfx->s6_addr, addr, o);
418 	if (b != 0)
419 		pfx->s6_addr[o] = addr->s6_addr[o] & (0xff00 >> b);
420 }
421 
422 static inline void ipv6_addr_prefix_copy(struct in6_addr *addr,
423 					 const struct in6_addr *pfx,
424 					 int plen)
425 {
426 	/* caller must guarantee 0 <= plen <= 128 */
427 	int o = plen >> 3,
428 	    b = plen & 0x7;
429 
430 	memcpy(addr->s6_addr, pfx, o);
431 	if (b != 0) {
432 		addr->s6_addr[o] &= ~(0xff00 >> b);
433 		addr->s6_addr[o] |= (pfx->s6_addr[o] & (0xff00 >> b));
434 	}
435 }
436 
437 static inline void __ipv6_addr_set_half(__be32 *addr,
438 					__be32 wh, __be32 wl)
439 {
440 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
441 #if defined(__BIG_ENDIAN)
442 	if (__builtin_constant_p(wh) && __builtin_constant_p(wl)) {
443 		*(__force u64 *)addr = ((__force u64)(wh) << 32 | (__force u64)(wl));
444 		return;
445 	}
446 #elif defined(__LITTLE_ENDIAN)
447 	if (__builtin_constant_p(wl) && __builtin_constant_p(wh)) {
448 		*(__force u64 *)addr = ((__force u64)(wl) << 32 | (__force u64)(wh));
449 		return;
450 	}
451 #endif
452 #endif
453 	addr[0] = wh;
454 	addr[1] = wl;
455 }
456 
457 static inline void ipv6_addr_set(struct in6_addr *addr,
458 				     __be32 w1, __be32 w2,
459 				     __be32 w3, __be32 w4)
460 {
461 	__ipv6_addr_set_half(&addr->s6_addr32[0], w1, w2);
462 	__ipv6_addr_set_half(&addr->s6_addr32[2], w3, w4);
463 }
464 
465 static inline bool ipv6_addr_equal(const struct in6_addr *a1,
466 				   const struct in6_addr *a2)
467 {
468 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
469 	const unsigned long *ul1 = (const unsigned long *)a1;
470 	const unsigned long *ul2 = (const unsigned long *)a2;
471 
472 	return ((ul1[0] ^ ul2[0]) | (ul1[1] ^ ul2[1])) == 0UL;
473 #else
474 	return ((a1->s6_addr32[0] ^ a2->s6_addr32[0]) |
475 		(a1->s6_addr32[1] ^ a2->s6_addr32[1]) |
476 		(a1->s6_addr32[2] ^ a2->s6_addr32[2]) |
477 		(a1->s6_addr32[3] ^ a2->s6_addr32[3])) == 0;
478 #endif
479 }
480 
481 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
482 static inline bool __ipv6_prefix_equal64_half(const __be64 *a1,
483 					      const __be64 *a2,
484 					      unsigned int len)
485 {
486 	if (len && ((*a1 ^ *a2) & cpu_to_be64((~0UL) << (64 - len))))
487 		return false;
488 	return true;
489 }
490 
491 static inline bool ipv6_prefix_equal(const struct in6_addr *addr1,
492 				     const struct in6_addr *addr2,
493 				     unsigned int prefixlen)
494 {
495 	const __be64 *a1 = (const __be64 *)addr1;
496 	const __be64 *a2 = (const __be64 *)addr2;
497 
498 	if (prefixlen >= 64) {
499 		if (a1[0] ^ a2[0])
500 			return false;
501 		return __ipv6_prefix_equal64_half(a1 + 1, a2 + 1, prefixlen - 64);
502 	}
503 	return __ipv6_prefix_equal64_half(a1, a2, prefixlen);
504 }
505 #else
506 static inline bool ipv6_prefix_equal(const struct in6_addr *addr1,
507 				     const struct in6_addr *addr2,
508 				     unsigned int prefixlen)
509 {
510 	const __be32 *a1 = addr1->s6_addr32;
511 	const __be32 *a2 = addr2->s6_addr32;
512 	unsigned int pdw, pbi;
513 
514 	/* check complete u32 in prefix */
515 	pdw = prefixlen >> 5;
516 	if (pdw && memcmp(a1, a2, pdw << 2))
517 		return false;
518 
519 	/* check incomplete u32 in prefix */
520 	pbi = prefixlen & 0x1f;
521 	if (pbi && ((a1[pdw] ^ a2[pdw]) & htonl((0xffffffff) << (32 - pbi))))
522 		return false;
523 
524 	return true;
525 }
526 #endif
527 
528 struct inet_frag_queue;
529 
530 enum ip6_defrag_users {
531 	IP6_DEFRAG_LOCAL_DELIVER,
532 	IP6_DEFRAG_CONNTRACK_IN,
533 	__IP6_DEFRAG_CONNTRACK_IN	= IP6_DEFRAG_CONNTRACK_IN + USHRT_MAX,
534 	IP6_DEFRAG_CONNTRACK_OUT,
535 	__IP6_DEFRAG_CONNTRACK_OUT	= IP6_DEFRAG_CONNTRACK_OUT + USHRT_MAX,
536 	IP6_DEFRAG_CONNTRACK_BRIDGE_IN,
537 	__IP6_DEFRAG_CONNTRACK_BRIDGE_IN = IP6_DEFRAG_CONNTRACK_BRIDGE_IN + USHRT_MAX,
538 };
539 
540 struct ip6_create_arg {
541 	__be32 id;
542 	u32 user;
543 	const struct in6_addr *src;
544 	const struct in6_addr *dst;
545 	int iif;
546 	u8 ecn;
547 };
548 
549 void ip6_frag_init(struct inet_frag_queue *q, const void *a);
550 bool ip6_frag_match(const struct inet_frag_queue *q, const void *a);
551 
552 /*
553  *	Equivalent of ipv4 struct ip
554  */
555 struct frag_queue {
556 	struct inet_frag_queue	q;
557 
558 	__be32			id;		/* fragment id		*/
559 	u32			user;
560 	struct in6_addr		saddr;
561 	struct in6_addr		daddr;
562 
563 	int			iif;
564 	unsigned int		csum;
565 	__u16			nhoffset;
566 	u8			ecn;
567 };
568 
569 void ip6_expire_frag_queue(struct net *net, struct frag_queue *fq,
570 			   struct inet_frags *frags);
571 
572 static inline bool ipv6_addr_any(const struct in6_addr *a)
573 {
574 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
575 	const unsigned long *ul = (const unsigned long *)a;
576 
577 	return (ul[0] | ul[1]) == 0UL;
578 #else
579 	return (a->s6_addr32[0] | a->s6_addr32[1] |
580 		a->s6_addr32[2] | a->s6_addr32[3]) == 0;
581 #endif
582 }
583 
584 static inline u32 ipv6_addr_hash(const struct in6_addr *a)
585 {
586 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
587 	const unsigned long *ul = (const unsigned long *)a;
588 	unsigned long x = ul[0] ^ ul[1];
589 
590 	return (u32)(x ^ (x >> 32));
591 #else
592 	return (__force u32)(a->s6_addr32[0] ^ a->s6_addr32[1] ^
593 			     a->s6_addr32[2] ^ a->s6_addr32[3]);
594 #endif
595 }
596 
597 /* more secured version of ipv6_addr_hash() */
598 static inline u32 __ipv6_addr_jhash(const struct in6_addr *a, const u32 initval)
599 {
600 	u32 v = (__force u32)a->s6_addr32[0] ^ (__force u32)a->s6_addr32[1];
601 
602 	return jhash_3words(v,
603 			    (__force u32)a->s6_addr32[2],
604 			    (__force u32)a->s6_addr32[3],
605 			    initval);
606 }
607 
608 static inline bool ipv6_addr_loopback(const struct in6_addr *a)
609 {
610 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
611 	const __be64 *be = (const __be64 *)a;
612 
613 	return (be[0] | (be[1] ^ cpu_to_be64(1))) == 0UL;
614 #else
615 	return (a->s6_addr32[0] | a->s6_addr32[1] |
616 		a->s6_addr32[2] | (a->s6_addr32[3] ^ cpu_to_be32(1))) == 0;
617 #endif
618 }
619 
620 /*
621  * Note that we must __force cast these to unsigned long to make sparse happy,
622  * since all of the endian-annotated types are fixed size regardless of arch.
623  */
624 static inline bool ipv6_addr_v4mapped(const struct in6_addr *a)
625 {
626 	return (
627 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
628 		*(unsigned long *)a |
629 #else
630 		(__force unsigned long)(a->s6_addr32[0] | a->s6_addr32[1]) |
631 #endif
632 		(__force unsigned long)(a->s6_addr32[2] ^
633 					cpu_to_be32(0x0000ffff))) == 0UL;
634 }
635 
636 /*
637  * Check for a RFC 4843 ORCHID address
638  * (Overlay Routable Cryptographic Hash Identifiers)
639  */
640 static inline bool ipv6_addr_orchid(const struct in6_addr *a)
641 {
642 	return (a->s6_addr32[0] & htonl(0xfffffff0)) == htonl(0x20010010);
643 }
644 
645 static inline bool ipv6_addr_is_multicast(const struct in6_addr *addr)
646 {
647 	return (addr->s6_addr32[0] & htonl(0xFF000000)) == htonl(0xFF000000);
648 }
649 
650 static inline void ipv6_addr_set_v4mapped(const __be32 addr,
651 					  struct in6_addr *v4mapped)
652 {
653 	ipv6_addr_set(v4mapped,
654 			0, 0,
655 			htonl(0x0000FFFF),
656 			addr);
657 }
658 
659 /*
660  * find the first different bit between two addresses
661  * length of address must be a multiple of 32bits
662  */
663 static inline int __ipv6_addr_diff32(const void *token1, const void *token2, int addrlen)
664 {
665 	const __be32 *a1 = token1, *a2 = token2;
666 	int i;
667 
668 	addrlen >>= 2;
669 
670 	for (i = 0; i < addrlen; i++) {
671 		__be32 xb = a1[i] ^ a2[i];
672 		if (xb)
673 			return i * 32 + 31 - __fls(ntohl(xb));
674 	}
675 
676 	/*
677 	 *	we should *never* get to this point since that
678 	 *	would mean the addrs are equal
679 	 *
680 	 *	However, we do get to it 8) And exacly, when
681 	 *	addresses are equal 8)
682 	 *
683 	 *	ip route add 1111::/128 via ...
684 	 *	ip route add 1111::/64 via ...
685 	 *	and we are here.
686 	 *
687 	 *	Ideally, this function should stop comparison
688 	 *	at prefix length. It does not, but it is still OK,
689 	 *	if returned value is greater than prefix length.
690 	 *					--ANK (980803)
691 	 */
692 	return addrlen << 5;
693 }
694 
695 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
696 static inline int __ipv6_addr_diff64(const void *token1, const void *token2, int addrlen)
697 {
698 	const __be64 *a1 = token1, *a2 = token2;
699 	int i;
700 
701 	addrlen >>= 3;
702 
703 	for (i = 0; i < addrlen; i++) {
704 		__be64 xb = a1[i] ^ a2[i];
705 		if (xb)
706 			return i * 64 + 63 - __fls(be64_to_cpu(xb));
707 	}
708 
709 	return addrlen << 6;
710 }
711 #endif
712 
713 static inline int __ipv6_addr_diff(const void *token1, const void *token2, int addrlen)
714 {
715 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
716 	if (__builtin_constant_p(addrlen) && !(addrlen & 7))
717 		return __ipv6_addr_diff64(token1, token2, addrlen);
718 #endif
719 	return __ipv6_addr_diff32(token1, token2, addrlen);
720 }
721 
722 static inline int ipv6_addr_diff(const struct in6_addr *a1, const struct in6_addr *a2)
723 {
724 	return __ipv6_addr_diff(a1, a2, sizeof(struct in6_addr));
725 }
726 
727 __be32 ipv6_select_ident(struct net *net,
728 			 const struct in6_addr *daddr,
729 			 const struct in6_addr *saddr);
730 void ipv6_proxy_select_ident(struct net *net, struct sk_buff *skb);
731 
732 int ip6_dst_hoplimit(struct dst_entry *dst);
733 
734 static inline int ip6_sk_dst_hoplimit(struct ipv6_pinfo *np, struct flowi6 *fl6,
735 				      struct dst_entry *dst)
736 {
737 	int hlimit;
738 
739 	if (ipv6_addr_is_multicast(&fl6->daddr))
740 		hlimit = np->mcast_hops;
741 	else
742 		hlimit = np->hop_limit;
743 	if (hlimit < 0)
744 		hlimit = ip6_dst_hoplimit(dst);
745 	return hlimit;
746 }
747 
748 /* copy IPv6 saddr & daddr to flow_keys, possibly using 64bit load/store
749  * Equivalent to :	flow->v6addrs.src = iph->saddr;
750  *			flow->v6addrs.dst = iph->daddr;
751  */
752 static inline void iph_to_flow_copy_v6addrs(struct flow_keys *flow,
753 					    const struct ipv6hdr *iph)
754 {
755 	BUILD_BUG_ON(offsetof(typeof(flow->addrs), v6addrs.dst) !=
756 		     offsetof(typeof(flow->addrs), v6addrs.src) +
757 		     sizeof(flow->addrs.v6addrs.src));
758 	memcpy(&flow->addrs.v6addrs, &iph->saddr, sizeof(flow->addrs.v6addrs));
759 	flow->control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
760 }
761 
762 #if IS_ENABLED(CONFIG_IPV6)
763 
764 /* Sysctl settings for net ipv6.auto_flowlabels */
765 #define IP6_AUTO_FLOW_LABEL_OFF		0
766 #define IP6_AUTO_FLOW_LABEL_OPTOUT	1
767 #define IP6_AUTO_FLOW_LABEL_OPTIN	2
768 #define IP6_AUTO_FLOW_LABEL_FORCED	3
769 
770 #define IP6_AUTO_FLOW_LABEL_MAX		IP6_AUTO_FLOW_LABEL_FORCED
771 
772 #define IP6_DEFAULT_AUTO_FLOW_LABELS	IP6_AUTO_FLOW_LABEL_OPTOUT
773 
774 static inline __be32 ip6_make_flowlabel(struct net *net, struct sk_buff *skb,
775 					__be32 flowlabel, bool autolabel,
776 					struct flowi6 *fl6)
777 {
778 	u32 hash;
779 
780 	/* @flowlabel may include more than a flow label, eg, the traffic class.
781 	 * Here we want only the flow label value.
782 	 */
783 	flowlabel &= IPV6_FLOWLABEL_MASK;
784 
785 	if (flowlabel ||
786 	    net->ipv6.sysctl.auto_flowlabels == IP6_AUTO_FLOW_LABEL_OFF ||
787 	    (!autolabel &&
788 	     net->ipv6.sysctl.auto_flowlabels != IP6_AUTO_FLOW_LABEL_FORCED))
789 		return flowlabel;
790 
791 	hash = skb_get_hash_flowi6(skb, fl6);
792 
793 	/* Since this is being sent on the wire obfuscate hash a bit
794 	 * to minimize possbility that any useful information to an
795 	 * attacker is leaked. Only lower 20 bits are relevant.
796 	 */
797 	rol32(hash, 16);
798 
799 	flowlabel = (__force __be32)hash & IPV6_FLOWLABEL_MASK;
800 
801 	if (net->ipv6.sysctl.flowlabel_state_ranges)
802 		flowlabel |= IPV6_FLOWLABEL_STATELESS_FLAG;
803 
804 	return flowlabel;
805 }
806 
807 static inline int ip6_default_np_autolabel(struct net *net)
808 {
809 	switch (net->ipv6.sysctl.auto_flowlabels) {
810 	case IP6_AUTO_FLOW_LABEL_OFF:
811 	case IP6_AUTO_FLOW_LABEL_OPTIN:
812 	default:
813 		return 0;
814 	case IP6_AUTO_FLOW_LABEL_OPTOUT:
815 	case IP6_AUTO_FLOW_LABEL_FORCED:
816 		return 1;
817 	}
818 }
819 #else
820 static inline void ip6_set_txhash(struct sock *sk) { }
821 static inline __be32 ip6_make_flowlabel(struct net *net, struct sk_buff *skb,
822 					__be32 flowlabel, bool autolabel,
823 					struct flowi6 *fl6)
824 {
825 	return flowlabel;
826 }
827 static inline int ip6_default_np_autolabel(struct net *net)
828 {
829 	return 0;
830 }
831 #endif
832 
833 
834 /*
835  *	Header manipulation
836  */
837 static inline void ip6_flow_hdr(struct ipv6hdr *hdr, unsigned int tclass,
838 				__be32 flowlabel)
839 {
840 	*(__be32 *)hdr = htonl(0x60000000 | (tclass << 20)) | flowlabel;
841 }
842 
843 static inline __be32 ip6_flowinfo(const struct ipv6hdr *hdr)
844 {
845 	return *(__be32 *)hdr & IPV6_FLOWINFO_MASK;
846 }
847 
848 static inline __be32 ip6_flowlabel(const struct ipv6hdr *hdr)
849 {
850 	return *(__be32 *)hdr & IPV6_FLOWLABEL_MASK;
851 }
852 
853 static inline u8 ip6_tclass(__be32 flowinfo)
854 {
855 	return ntohl(flowinfo & IPV6_TCLASS_MASK) >> IPV6_TCLASS_SHIFT;
856 }
857 
858 static inline __be32 ip6_make_flowinfo(unsigned int tclass, __be32 flowlabel)
859 {
860 	return htonl(tclass << IPV6_TCLASS_SHIFT) | flowlabel;
861 }
862 
863 /*
864  *	Prototypes exported by ipv6
865  */
866 
867 /*
868  *	rcv function (called from netdevice level)
869  */
870 
871 int ipv6_rcv(struct sk_buff *skb, struct net_device *dev,
872 	     struct packet_type *pt, struct net_device *orig_dev);
873 
874 int ip6_rcv_finish(struct net *net, struct sock *sk, struct sk_buff *skb);
875 
876 /*
877  *	upper-layer output functions
878  */
879 int ip6_xmit(const struct sock *sk, struct sk_buff *skb, struct flowi6 *fl6,
880 	     __u32 mark, struct ipv6_txoptions *opt, int tclass);
881 
882 int ip6_find_1stfragopt(struct sk_buff *skb, u8 **nexthdr);
883 
884 int ip6_append_data(struct sock *sk,
885 		    int getfrag(void *from, char *to, int offset, int len,
886 				int odd, struct sk_buff *skb),
887 		    void *from, int length, int transhdrlen,
888 		    struct ipcm6_cookie *ipc6, struct flowi6 *fl6,
889 		    struct rt6_info *rt, unsigned int flags,
890 		    const struct sockcm_cookie *sockc);
891 
892 int ip6_push_pending_frames(struct sock *sk);
893 
894 void ip6_flush_pending_frames(struct sock *sk);
895 
896 int ip6_send_skb(struct sk_buff *skb);
897 
898 struct sk_buff *__ip6_make_skb(struct sock *sk, struct sk_buff_head *queue,
899 			       struct inet_cork_full *cork,
900 			       struct inet6_cork *v6_cork);
901 struct sk_buff *ip6_make_skb(struct sock *sk,
902 			     int getfrag(void *from, char *to, int offset,
903 					 int len, int odd, struct sk_buff *skb),
904 			     void *from, int length, int transhdrlen,
905 			     struct ipcm6_cookie *ipc6, struct flowi6 *fl6,
906 			     struct rt6_info *rt, unsigned int flags,
907 			     const struct sockcm_cookie *sockc);
908 
909 static inline struct sk_buff *ip6_finish_skb(struct sock *sk)
910 {
911 	return __ip6_make_skb(sk, &sk->sk_write_queue, &inet_sk(sk)->cork,
912 			      &inet6_sk(sk)->cork);
913 }
914 
915 int ip6_dst_lookup(struct net *net, struct sock *sk, struct dst_entry **dst,
916 		   struct flowi6 *fl6);
917 struct dst_entry *ip6_dst_lookup_flow(const struct sock *sk, struct flowi6 *fl6,
918 				      const struct in6_addr *final_dst);
919 struct dst_entry *ip6_sk_dst_lookup_flow(struct sock *sk, struct flowi6 *fl6,
920 					 const struct in6_addr *final_dst);
921 struct dst_entry *ip6_blackhole_route(struct net *net,
922 				      struct dst_entry *orig_dst);
923 
924 /*
925  *	skb processing functions
926  */
927 
928 int ip6_output(struct net *net, struct sock *sk, struct sk_buff *skb);
929 int ip6_forward(struct sk_buff *skb);
930 int ip6_input(struct sk_buff *skb);
931 int ip6_mc_input(struct sk_buff *skb);
932 
933 int __ip6_local_out(struct net *net, struct sock *sk, struct sk_buff *skb);
934 int ip6_local_out(struct net *net, struct sock *sk, struct sk_buff *skb);
935 
936 /*
937  *	Extension header (options) processing
938  */
939 
940 void ipv6_push_nfrag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt,
941 			  u8 *proto, struct in6_addr **daddr_p,
942 			  struct in6_addr *saddr);
943 void ipv6_push_frag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt,
944 			 u8 *proto);
945 
946 int ipv6_skip_exthdr(const struct sk_buff *, int start, u8 *nexthdrp,
947 		     __be16 *frag_offp);
948 
949 bool ipv6_ext_hdr(u8 nexthdr);
950 
951 enum {
952 	IP6_FH_F_FRAG		= (1 << 0),
953 	IP6_FH_F_AUTH		= (1 << 1),
954 	IP6_FH_F_SKIP_RH	= (1 << 2),
955 };
956 
957 /* find specified header and get offset to it */
958 int ipv6_find_hdr(const struct sk_buff *skb, unsigned int *offset, int target,
959 		  unsigned short *fragoff, int *fragflg);
960 
961 int ipv6_find_tlv(const struct sk_buff *skb, int offset, int type);
962 
963 struct in6_addr *fl6_update_dst(struct flowi6 *fl6,
964 				const struct ipv6_txoptions *opt,
965 				struct in6_addr *orig);
966 
967 /*
968  *	socket options (ipv6_sockglue.c)
969  */
970 
971 int ipv6_setsockopt(struct sock *sk, int level, int optname,
972 		    char __user *optval, unsigned int optlen);
973 int ipv6_getsockopt(struct sock *sk, int level, int optname,
974 		    char __user *optval, int __user *optlen);
975 int compat_ipv6_setsockopt(struct sock *sk, int level, int optname,
976 			   char __user *optval, unsigned int optlen);
977 int compat_ipv6_getsockopt(struct sock *sk, int level, int optname,
978 			   char __user *optval, int __user *optlen);
979 
980 int __ip6_datagram_connect(struct sock *sk, struct sockaddr *addr,
981 			   int addr_len);
982 int ip6_datagram_connect(struct sock *sk, struct sockaddr *addr, int addr_len);
983 int ip6_datagram_connect_v6_only(struct sock *sk, struct sockaddr *addr,
984 				 int addr_len);
985 int ip6_datagram_dst_update(struct sock *sk, bool fix_sk_saddr);
986 void ip6_datagram_release_cb(struct sock *sk);
987 
988 int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len,
989 		    int *addr_len);
990 int ipv6_recv_rxpmtu(struct sock *sk, struct msghdr *msg, int len,
991 		     int *addr_len);
992 void ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err, __be16 port,
993 		     u32 info, u8 *payload);
994 void ipv6_local_error(struct sock *sk, int err, struct flowi6 *fl6, u32 info);
995 void ipv6_local_rxpmtu(struct sock *sk, struct flowi6 *fl6, u32 mtu);
996 
997 int inet6_release(struct socket *sock);
998 int inet6_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len);
999 int inet6_getname(struct socket *sock, struct sockaddr *uaddr, int *uaddr_len,
1000 		  int peer);
1001 int inet6_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg);
1002 
1003 int inet6_hash_connect(struct inet_timewait_death_row *death_row,
1004 			      struct sock *sk);
1005 
1006 /*
1007  * reassembly.c
1008  */
1009 extern const struct proto_ops inet6_stream_ops;
1010 extern const struct proto_ops inet6_dgram_ops;
1011 extern const struct proto_ops inet6_sockraw_ops;
1012 
1013 struct group_source_req;
1014 struct group_filter;
1015 
1016 int ip6_mc_source(int add, int omode, struct sock *sk,
1017 		  struct group_source_req *pgsr);
1018 int ip6_mc_msfilter(struct sock *sk, struct group_filter *gsf);
1019 int ip6_mc_msfget(struct sock *sk, struct group_filter *gsf,
1020 		  struct group_filter __user *optval, int __user *optlen);
1021 
1022 #ifdef CONFIG_PROC_FS
1023 int ac6_proc_init(struct net *net);
1024 void ac6_proc_exit(struct net *net);
1025 int raw6_proc_init(void);
1026 void raw6_proc_exit(void);
1027 int tcp6_proc_init(struct net *net);
1028 void tcp6_proc_exit(struct net *net);
1029 int udp6_proc_init(struct net *net);
1030 void udp6_proc_exit(struct net *net);
1031 int udplite6_proc_init(void);
1032 void udplite6_proc_exit(void);
1033 int ipv6_misc_proc_init(void);
1034 void ipv6_misc_proc_exit(void);
1035 int snmp6_register_dev(struct inet6_dev *idev);
1036 int snmp6_unregister_dev(struct inet6_dev *idev);
1037 
1038 #else
1039 static inline int ac6_proc_init(struct net *net) { return 0; }
1040 static inline void ac6_proc_exit(struct net *net) { }
1041 static inline int snmp6_register_dev(struct inet6_dev *idev) { return 0; }
1042 static inline int snmp6_unregister_dev(struct inet6_dev *idev) { return 0; }
1043 #endif
1044 
1045 #ifdef CONFIG_SYSCTL
1046 extern struct ctl_table ipv6_route_table_template[];
1047 
1048 struct ctl_table *ipv6_icmp_sysctl_init(struct net *net);
1049 struct ctl_table *ipv6_route_sysctl_init(struct net *net);
1050 int ipv6_sysctl_register(void);
1051 void ipv6_sysctl_unregister(void);
1052 #endif
1053 
1054 int ipv6_sock_mc_join(struct sock *sk, int ifindex,
1055 		      const struct in6_addr *addr);
1056 int ipv6_sock_mc_drop(struct sock *sk, int ifindex,
1057 		      const struct in6_addr *addr);
1058 #endif /* _NET_IPV6_H */
1059