xref: /openbmc/linux/include/net/ipv6.h (revision 78700c0a)
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/flow_dissector.h>
23 #include <net/snmp.h>
24 
25 #define SIN6_LEN_RFC2133	24
26 
27 #define IPV6_MAXPLEN		65535
28 
29 /*
30  *	NextHeader field of IPv6 header
31  */
32 
33 #define NEXTHDR_HOP		0	/* Hop-by-hop option header. */
34 #define NEXTHDR_TCP		6	/* TCP segment. */
35 #define NEXTHDR_UDP		17	/* UDP message. */
36 #define NEXTHDR_IPV6		41	/* IPv6 in IPv6 */
37 #define NEXTHDR_ROUTING		43	/* Routing header. */
38 #define NEXTHDR_FRAGMENT	44	/* Fragmentation/reassembly header. */
39 #define NEXTHDR_GRE		47	/* GRE header. */
40 #define NEXTHDR_ESP		50	/* Encapsulating security payload. */
41 #define NEXTHDR_AUTH		51	/* Authentication header. */
42 #define NEXTHDR_ICMP		58	/* ICMP for IPv6. */
43 #define NEXTHDR_NONE		59	/* No next header */
44 #define NEXTHDR_DEST		60	/* Destination options header. */
45 #define NEXTHDR_SCTP		132	/* SCTP message. */
46 #define NEXTHDR_MOBILITY	135	/* Mobility header. */
47 
48 #define NEXTHDR_MAX		255
49 
50 #define IPV6_DEFAULT_HOPLIMIT   64
51 #define IPV6_DEFAULT_MCASTHOPS	1
52 
53 /*
54  *	Addr type
55  *
56  *	type	-	unicast | multicast
57  *	scope	-	local	| site	    | global
58  *	v4	-	compat
59  *	v4mapped
60  *	any
61  *	loopback
62  */
63 
64 #define IPV6_ADDR_ANY		0x0000U
65 
66 #define IPV6_ADDR_UNICAST      	0x0001U
67 #define IPV6_ADDR_MULTICAST    	0x0002U
68 
69 #define IPV6_ADDR_LOOPBACK	0x0010U
70 #define IPV6_ADDR_LINKLOCAL	0x0020U
71 #define IPV6_ADDR_SITELOCAL	0x0040U
72 
73 #define IPV6_ADDR_COMPATv4	0x0080U
74 
75 #define IPV6_ADDR_SCOPE_MASK	0x00f0U
76 
77 #define IPV6_ADDR_MAPPED	0x1000U
78 
79 /*
80  *	Addr scopes
81  */
82 #define IPV6_ADDR_MC_SCOPE(a)	\
83 	((a)->s6_addr[1] & 0x0f)	/* nonstandard */
84 #define __IPV6_ADDR_SCOPE_INVALID	-1
85 #define IPV6_ADDR_SCOPE_NODELOCAL	0x01
86 #define IPV6_ADDR_SCOPE_LINKLOCAL	0x02
87 #define IPV6_ADDR_SCOPE_SITELOCAL	0x05
88 #define IPV6_ADDR_SCOPE_ORGLOCAL	0x08
89 #define IPV6_ADDR_SCOPE_GLOBAL		0x0e
90 
91 /*
92  *	Addr flags
93  */
94 #define IPV6_ADDR_MC_FLAG_TRANSIENT(a)	\
95 	((a)->s6_addr[1] & 0x10)
96 #define IPV6_ADDR_MC_FLAG_PREFIX(a)	\
97 	((a)->s6_addr[1] & 0x20)
98 #define IPV6_ADDR_MC_FLAG_RENDEZVOUS(a)	\
99 	((a)->s6_addr[1] & 0x40)
100 
101 /*
102  *	fragmentation header
103  */
104 
105 struct frag_hdr {
106 	__u8	nexthdr;
107 	__u8	reserved;
108 	__be16	frag_off;
109 	__be32	identification;
110 };
111 
112 #define	IP6_MF		0x0001
113 #define	IP6_OFFSET	0xFFF8
114 
115 #define IP6_REPLY_MARK(net, mark) \
116 	((net)->ipv6.sysctl.fwmark_reflect ? (mark) : 0)
117 
118 #include <net/sock.h>
119 
120 /* sysctls */
121 extern int sysctl_mld_max_msf;
122 extern int sysctl_mld_qrv;
123 
124 #define _DEVINC(net, statname, mod, idev, field)			\
125 ({									\
126 	struct inet6_dev *_idev = (idev);				\
127 	if (likely(_idev != NULL))					\
128 		mod##SNMP_INC_STATS64((_idev)->stats.statname, (field));\
129 	mod##SNMP_INC_STATS64((net)->mib.statname##_statistics, (field));\
130 })
131 
132 /* per device counters are atomic_long_t */
133 #define _DEVINCATOMIC(net, statname, mod, idev, field)			\
134 ({									\
135 	struct inet6_dev *_idev = (idev);				\
136 	if (likely(_idev != NULL))					\
137 		SNMP_INC_STATS_ATOMIC_LONG((_idev)->stats.statname##dev, (field)); \
138 	mod##SNMP_INC_STATS((net)->mib.statname##_statistics, (field));\
139 })
140 
141 /* per device and per net counters are atomic_long_t */
142 #define _DEVINC_ATOMIC_ATOMIC(net, statname, idev, field)		\
143 ({									\
144 	struct inet6_dev *_idev = (idev);				\
145 	if (likely(_idev != NULL))					\
146 		SNMP_INC_STATS_ATOMIC_LONG((_idev)->stats.statname##dev, (field)); \
147 	SNMP_INC_STATS_ATOMIC_LONG((net)->mib.statname##_statistics, (field));\
148 })
149 
150 #define _DEVADD(net, statname, mod, idev, field, val)			\
151 ({									\
152 	struct inet6_dev *_idev = (idev);				\
153 	if (likely(_idev != NULL))					\
154 		mod##SNMP_ADD_STATS((_idev)->stats.statname, (field), (val)); \
155 	mod##SNMP_ADD_STATS((net)->mib.statname##_statistics, (field), (val));\
156 })
157 
158 #define _DEVUPD(net, statname, mod, idev, field, val)			\
159 ({									\
160 	struct inet6_dev *_idev = (idev);				\
161 	if (likely(_idev != NULL))					\
162 		mod##SNMP_UPD_PO_STATS((_idev)->stats.statname, field, (val)); \
163 	mod##SNMP_UPD_PO_STATS((net)->mib.statname##_statistics, field, (val));\
164 })
165 
166 /* MIBs */
167 
168 #define IP6_INC_STATS(net, idev,field)		\
169 		_DEVINC(net, ipv6, , idev, field)
170 #define __IP6_INC_STATS(net, idev,field)	\
171 		_DEVINC(net, ipv6, __, idev, field)
172 #define IP6_ADD_STATS(net, idev,field,val)	\
173 		_DEVADD(net, ipv6, , idev, field, val)
174 #define __IP6_ADD_STATS(net, idev,field,val)	\
175 		_DEVADD(net, ipv6, __, idev, field, val)
176 #define IP6_UPD_PO_STATS(net, idev,field,val)   \
177 		_DEVUPD(net, ipv6, , idev, field, val)
178 #define __IP6_UPD_PO_STATS(net, idev,field,val)   \
179 		_DEVUPD(net, ipv6, __, idev, field, val)
180 #define ICMP6_INC_STATS(net, idev, field)	\
181 		_DEVINCATOMIC(net, icmpv6, , idev, field)
182 #define __ICMP6_INC_STATS(net, idev, field)	\
183 		_DEVINCATOMIC(net, icmpv6, __, idev, field)
184 
185 #define ICMP6MSGOUT_INC_STATS(net, idev, field)		\
186 	_DEVINC_ATOMIC_ATOMIC(net, icmpv6msg, idev, field +256)
187 #define ICMP6MSGIN_INC_STATS(net, idev, field)	\
188 	_DEVINC_ATOMIC_ATOMIC(net, icmpv6msg, idev, field)
189 
190 struct ip6_ra_chain {
191 	struct ip6_ra_chain	*next;
192 	struct sock		*sk;
193 	int			sel;
194 	void			(*destructor)(struct sock *);
195 };
196 
197 extern struct ip6_ra_chain	*ip6_ra_chain;
198 extern rwlock_t ip6_ra_lock;
199 
200 /*
201    This structure is prepared by protocol, when parsing
202    ancillary data and passed to IPv6.
203  */
204 
205 struct ipv6_txoptions {
206 	atomic_t		refcnt;
207 	/* Length of this structure */
208 	int			tot_len;
209 
210 	/* length of extension headers   */
211 
212 	__u16			opt_flen;	/* after fragment hdr */
213 	__u16			opt_nflen;	/* before fragment hdr */
214 
215 	struct ipv6_opt_hdr	*hopopt;
216 	struct ipv6_opt_hdr	*dst0opt;
217 	struct ipv6_rt_hdr	*srcrt;	/* Routing Header */
218 	struct ipv6_opt_hdr	*dst1opt;
219 	struct rcu_head		rcu;
220 	/* Option buffer, as read by IPV6_PKTOPTIONS, starts here. */
221 };
222 
223 struct ip6_flowlabel {
224 	struct ip6_flowlabel __rcu *next;
225 	__be32			label;
226 	atomic_t		users;
227 	struct in6_addr		dst;
228 	struct ipv6_txoptions	*opt;
229 	unsigned long		linger;
230 	struct rcu_head		rcu;
231 	u8			share;
232 	union {
233 		struct pid *pid;
234 		kuid_t uid;
235 	} owner;
236 	unsigned long		lastuse;
237 	unsigned long		expires;
238 	struct net		*fl_net;
239 };
240 
241 #define IPV6_FLOWINFO_MASK		cpu_to_be32(0x0FFFFFFF)
242 #define IPV6_FLOWLABEL_MASK		cpu_to_be32(0x000FFFFF)
243 #define IPV6_FLOWLABEL_STATELESS_FLAG	cpu_to_be32(0x00080000)
244 
245 #define IPV6_TCLASS_MASK (IPV6_FLOWINFO_MASK & ~IPV6_FLOWLABEL_MASK)
246 #define IPV6_TCLASS_SHIFT	20
247 
248 struct ipv6_fl_socklist {
249 	struct ipv6_fl_socklist	__rcu	*next;
250 	struct ip6_flowlabel		*fl;
251 	struct rcu_head			rcu;
252 };
253 
254 struct ipcm6_cookie {
255 	__s16 hlimit;
256 	__s16 tclass;
257 	__s8  dontfrag;
258 	struct ipv6_txoptions *opt;
259 };
260 
261 static inline struct ipv6_txoptions *txopt_get(const struct ipv6_pinfo *np)
262 {
263 	struct ipv6_txoptions *opt;
264 
265 	rcu_read_lock();
266 	opt = rcu_dereference(np->opt);
267 	if (opt) {
268 		if (!atomic_inc_not_zero(&opt->refcnt))
269 			opt = NULL;
270 		else
271 			opt = rcu_pointer_handoff(opt);
272 	}
273 	rcu_read_unlock();
274 	return opt;
275 }
276 
277 static inline void txopt_put(struct ipv6_txoptions *opt)
278 {
279 	if (opt && atomic_dec_and_test(&opt->refcnt))
280 		kfree_rcu(opt, rcu);
281 }
282 
283 struct ip6_flowlabel *fl6_sock_lookup(struct sock *sk, __be32 label);
284 struct ipv6_txoptions *fl6_merge_options(struct ipv6_txoptions *opt_space,
285 					 struct ip6_flowlabel *fl,
286 					 struct ipv6_txoptions *fopt);
287 void fl6_free_socklist(struct sock *sk);
288 int ipv6_flowlabel_opt(struct sock *sk, char __user *optval, int optlen);
289 int ipv6_flowlabel_opt_get(struct sock *sk, struct in6_flowlabel_req *freq,
290 			   int flags);
291 int ip6_flowlabel_init(void);
292 void ip6_flowlabel_cleanup(void);
293 
294 static inline void fl6_sock_release(struct ip6_flowlabel *fl)
295 {
296 	if (fl)
297 		atomic_dec(&fl->users);
298 }
299 
300 void icmpv6_notify(struct sk_buff *skb, u8 type, u8 code, __be32 info);
301 
302 int icmpv6_push_pending_frames(struct sock *sk, struct flowi6 *fl6,
303 			       struct icmp6hdr *thdr, int len);
304 
305 int ip6_ra_control(struct sock *sk, int sel);
306 
307 int ipv6_parse_hopopts(struct sk_buff *skb);
308 
309 struct ipv6_txoptions *ipv6_dup_options(struct sock *sk,
310 					struct ipv6_txoptions *opt);
311 struct ipv6_txoptions *ipv6_renew_options(struct sock *sk,
312 					  struct ipv6_txoptions *opt,
313 					  int newtype,
314 					  struct ipv6_opt_hdr __user *newopt,
315 					  int newoptlen);
316 struct ipv6_txoptions *ipv6_fixup_options(struct ipv6_txoptions *opt_space,
317 					  struct ipv6_txoptions *opt);
318 
319 bool ipv6_opt_accepted(const struct sock *sk, const struct sk_buff *skb,
320 		       const struct inet6_skb_parm *opt);
321 
322 static inline bool ipv6_accept_ra(struct inet6_dev *idev)
323 {
324 	/* If forwarding is enabled, RA are not accepted unless the special
325 	 * hybrid mode (accept_ra=2) is enabled.
326 	 */
327 	return idev->cnf.forwarding ? idev->cnf.accept_ra == 2 :
328 	    idev->cnf.accept_ra;
329 }
330 
331 #if IS_ENABLED(CONFIG_IPV6)
332 static inline int ip6_frag_mem(struct net *net)
333 {
334 	return sum_frag_mem_limit(&net->ipv6.frags);
335 }
336 #endif
337 
338 #define IPV6_FRAG_HIGH_THRESH	(4 * 1024*1024)	/* 4194304 */
339 #define IPV6_FRAG_LOW_THRESH	(3 * 1024*1024)	/* 3145728 */
340 #define IPV6_FRAG_TIMEOUT	(60 * HZ)	/* 60 seconds */
341 
342 int __ipv6_addr_type(const struct in6_addr *addr);
343 static inline int ipv6_addr_type(const struct in6_addr *addr)
344 {
345 	return __ipv6_addr_type(addr) & 0xffff;
346 }
347 
348 static inline int ipv6_addr_scope(const struct in6_addr *addr)
349 {
350 	return __ipv6_addr_type(addr) & IPV6_ADDR_SCOPE_MASK;
351 }
352 
353 static inline int __ipv6_addr_src_scope(int type)
354 {
355 	return (type == IPV6_ADDR_ANY) ? __IPV6_ADDR_SCOPE_INVALID : (type >> 16);
356 }
357 
358 static inline int ipv6_addr_src_scope(const struct in6_addr *addr)
359 {
360 	return __ipv6_addr_src_scope(__ipv6_addr_type(addr));
361 }
362 
363 static inline bool __ipv6_addr_needs_scope_id(int type)
364 {
365 	return type & IPV6_ADDR_LINKLOCAL ||
366 	       (type & IPV6_ADDR_MULTICAST &&
367 		(type & (IPV6_ADDR_LOOPBACK|IPV6_ADDR_LINKLOCAL)));
368 }
369 
370 static inline __u32 ipv6_iface_scope_id(const struct in6_addr *addr, int iface)
371 {
372 	return __ipv6_addr_needs_scope_id(__ipv6_addr_type(addr)) ? iface : 0;
373 }
374 
375 static inline int ipv6_addr_cmp(const struct in6_addr *a1, const struct in6_addr *a2)
376 {
377 	return memcmp(a1, a2, sizeof(struct in6_addr));
378 }
379 
380 static inline bool
381 ipv6_masked_addr_cmp(const struct in6_addr *a1, const struct in6_addr *m,
382 		     const struct in6_addr *a2)
383 {
384 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
385 	const unsigned long *ul1 = (const unsigned long *)a1;
386 	const unsigned long *ulm = (const unsigned long *)m;
387 	const unsigned long *ul2 = (const unsigned long *)a2;
388 
389 	return !!(((ul1[0] ^ ul2[0]) & ulm[0]) |
390 		  ((ul1[1] ^ ul2[1]) & ulm[1]));
391 #else
392 	return !!(((a1->s6_addr32[0] ^ a2->s6_addr32[0]) & m->s6_addr32[0]) |
393 		  ((a1->s6_addr32[1] ^ a2->s6_addr32[1]) & m->s6_addr32[1]) |
394 		  ((a1->s6_addr32[2] ^ a2->s6_addr32[2]) & m->s6_addr32[2]) |
395 		  ((a1->s6_addr32[3] ^ a2->s6_addr32[3]) & m->s6_addr32[3]));
396 #endif
397 }
398 
399 static inline void ipv6_addr_prefix(struct in6_addr *pfx,
400 				    const struct in6_addr *addr,
401 				    int plen)
402 {
403 	/* caller must guarantee 0 <= plen <= 128 */
404 	int o = plen >> 3,
405 	    b = plen & 0x7;
406 
407 	memset(pfx->s6_addr, 0, sizeof(pfx->s6_addr));
408 	memcpy(pfx->s6_addr, addr, o);
409 	if (b != 0)
410 		pfx->s6_addr[o] = addr->s6_addr[o] & (0xff00 >> b);
411 }
412 
413 static inline void ipv6_addr_prefix_copy(struct in6_addr *addr,
414 					 const struct in6_addr *pfx,
415 					 int plen)
416 {
417 	/* caller must guarantee 0 <= plen <= 128 */
418 	int o = plen >> 3,
419 	    b = plen & 0x7;
420 
421 	memcpy(addr->s6_addr, pfx, o);
422 	if (b != 0) {
423 		addr->s6_addr[o] &= ~(0xff00 >> b);
424 		addr->s6_addr[o] |= (pfx->s6_addr[o] & (0xff00 >> b));
425 	}
426 }
427 
428 static inline void __ipv6_addr_set_half(__be32 *addr,
429 					__be32 wh, __be32 wl)
430 {
431 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
432 #if defined(__BIG_ENDIAN)
433 	if (__builtin_constant_p(wh) && __builtin_constant_p(wl)) {
434 		*(__force u64 *)addr = ((__force u64)(wh) << 32 | (__force u64)(wl));
435 		return;
436 	}
437 #elif defined(__LITTLE_ENDIAN)
438 	if (__builtin_constant_p(wl) && __builtin_constant_p(wh)) {
439 		*(__force u64 *)addr = ((__force u64)(wl) << 32 | (__force u64)(wh));
440 		return;
441 	}
442 #endif
443 #endif
444 	addr[0] = wh;
445 	addr[1] = wl;
446 }
447 
448 static inline void ipv6_addr_set(struct in6_addr *addr,
449 				     __be32 w1, __be32 w2,
450 				     __be32 w3, __be32 w4)
451 {
452 	__ipv6_addr_set_half(&addr->s6_addr32[0], w1, w2);
453 	__ipv6_addr_set_half(&addr->s6_addr32[2], w3, w4);
454 }
455 
456 static inline bool ipv6_addr_equal(const struct in6_addr *a1,
457 				   const struct in6_addr *a2)
458 {
459 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
460 	const unsigned long *ul1 = (const unsigned long *)a1;
461 	const unsigned long *ul2 = (const unsigned long *)a2;
462 
463 	return ((ul1[0] ^ ul2[0]) | (ul1[1] ^ ul2[1])) == 0UL;
464 #else
465 	return ((a1->s6_addr32[0] ^ a2->s6_addr32[0]) |
466 		(a1->s6_addr32[1] ^ a2->s6_addr32[1]) |
467 		(a1->s6_addr32[2] ^ a2->s6_addr32[2]) |
468 		(a1->s6_addr32[3] ^ a2->s6_addr32[3])) == 0;
469 #endif
470 }
471 
472 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
473 static inline bool __ipv6_prefix_equal64_half(const __be64 *a1,
474 					      const __be64 *a2,
475 					      unsigned int len)
476 {
477 	if (len && ((*a1 ^ *a2) & cpu_to_be64((~0UL) << (64 - len))))
478 		return false;
479 	return true;
480 }
481 
482 static inline bool ipv6_prefix_equal(const struct in6_addr *addr1,
483 				     const struct in6_addr *addr2,
484 				     unsigned int prefixlen)
485 {
486 	const __be64 *a1 = (const __be64 *)addr1;
487 	const __be64 *a2 = (const __be64 *)addr2;
488 
489 	if (prefixlen >= 64) {
490 		if (a1[0] ^ a2[0])
491 			return false;
492 		return __ipv6_prefix_equal64_half(a1 + 1, a2 + 1, prefixlen - 64);
493 	}
494 	return __ipv6_prefix_equal64_half(a1, a2, prefixlen);
495 }
496 #else
497 static inline bool ipv6_prefix_equal(const struct in6_addr *addr1,
498 				     const struct in6_addr *addr2,
499 				     unsigned int prefixlen)
500 {
501 	const __be32 *a1 = addr1->s6_addr32;
502 	const __be32 *a2 = addr2->s6_addr32;
503 	unsigned int pdw, pbi;
504 
505 	/* check complete u32 in prefix */
506 	pdw = prefixlen >> 5;
507 	if (pdw && memcmp(a1, a2, pdw << 2))
508 		return false;
509 
510 	/* check incomplete u32 in prefix */
511 	pbi = prefixlen & 0x1f;
512 	if (pbi && ((a1[pdw] ^ a2[pdw]) & htonl((0xffffffff) << (32 - pbi))))
513 		return false;
514 
515 	return true;
516 }
517 #endif
518 
519 struct inet_frag_queue;
520 
521 enum ip6_defrag_users {
522 	IP6_DEFRAG_LOCAL_DELIVER,
523 	IP6_DEFRAG_CONNTRACK_IN,
524 	__IP6_DEFRAG_CONNTRACK_IN	= IP6_DEFRAG_CONNTRACK_IN + USHRT_MAX,
525 	IP6_DEFRAG_CONNTRACK_OUT,
526 	__IP6_DEFRAG_CONNTRACK_OUT	= IP6_DEFRAG_CONNTRACK_OUT + USHRT_MAX,
527 	IP6_DEFRAG_CONNTRACK_BRIDGE_IN,
528 	__IP6_DEFRAG_CONNTRACK_BRIDGE_IN = IP6_DEFRAG_CONNTRACK_BRIDGE_IN + USHRT_MAX,
529 };
530 
531 struct ip6_create_arg {
532 	__be32 id;
533 	u32 user;
534 	const struct in6_addr *src;
535 	const struct in6_addr *dst;
536 	int iif;
537 	u8 ecn;
538 };
539 
540 void ip6_frag_init(struct inet_frag_queue *q, const void *a);
541 bool ip6_frag_match(const struct inet_frag_queue *q, const void *a);
542 
543 /*
544  *	Equivalent of ipv4 struct ip
545  */
546 struct frag_queue {
547 	struct inet_frag_queue	q;
548 
549 	__be32			id;		/* fragment id		*/
550 	u32			user;
551 	struct in6_addr		saddr;
552 	struct in6_addr		daddr;
553 
554 	int			iif;
555 	unsigned int		csum;
556 	__u16			nhoffset;
557 	u8			ecn;
558 };
559 
560 void ip6_expire_frag_queue(struct net *net, struct frag_queue *fq,
561 			   struct inet_frags *frags);
562 
563 static inline bool ipv6_addr_any(const struct in6_addr *a)
564 {
565 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
566 	const unsigned long *ul = (const unsigned long *)a;
567 
568 	return (ul[0] | ul[1]) == 0UL;
569 #else
570 	return (a->s6_addr32[0] | a->s6_addr32[1] |
571 		a->s6_addr32[2] | a->s6_addr32[3]) == 0;
572 #endif
573 }
574 
575 static inline u32 ipv6_addr_hash(const struct in6_addr *a)
576 {
577 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
578 	const unsigned long *ul = (const unsigned long *)a;
579 	unsigned long x = ul[0] ^ ul[1];
580 
581 	return (u32)(x ^ (x >> 32));
582 #else
583 	return (__force u32)(a->s6_addr32[0] ^ a->s6_addr32[1] ^
584 			     a->s6_addr32[2] ^ a->s6_addr32[3]);
585 #endif
586 }
587 
588 /* more secured version of ipv6_addr_hash() */
589 static inline u32 __ipv6_addr_jhash(const struct in6_addr *a, const u32 initval)
590 {
591 	u32 v = (__force u32)a->s6_addr32[0] ^ (__force u32)a->s6_addr32[1];
592 
593 	return jhash_3words(v,
594 			    (__force u32)a->s6_addr32[2],
595 			    (__force u32)a->s6_addr32[3],
596 			    initval);
597 }
598 
599 static inline bool ipv6_addr_loopback(const struct in6_addr *a)
600 {
601 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
602 	const __be64 *be = (const __be64 *)a;
603 
604 	return (be[0] | (be[1] ^ cpu_to_be64(1))) == 0UL;
605 #else
606 	return (a->s6_addr32[0] | a->s6_addr32[1] |
607 		a->s6_addr32[2] | (a->s6_addr32[3] ^ cpu_to_be32(1))) == 0;
608 #endif
609 }
610 
611 /*
612  * Note that we must __force cast these to unsigned long to make sparse happy,
613  * since all of the endian-annotated types are fixed size regardless of arch.
614  */
615 static inline bool ipv6_addr_v4mapped(const struct in6_addr *a)
616 {
617 	return (
618 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
619 		*(unsigned long *)a |
620 #else
621 		(__force unsigned long)(a->s6_addr32[0] | a->s6_addr32[1]) |
622 #endif
623 		(__force unsigned long)(a->s6_addr32[2] ^
624 					cpu_to_be32(0x0000ffff))) == 0UL;
625 }
626 
627 /*
628  * Check for a RFC 4843 ORCHID address
629  * (Overlay Routable Cryptographic Hash Identifiers)
630  */
631 static inline bool ipv6_addr_orchid(const struct in6_addr *a)
632 {
633 	return (a->s6_addr32[0] & htonl(0xfffffff0)) == htonl(0x20010010);
634 }
635 
636 static inline bool ipv6_addr_is_multicast(const struct in6_addr *addr)
637 {
638 	return (addr->s6_addr32[0] & htonl(0xFF000000)) == htonl(0xFF000000);
639 }
640 
641 static inline void ipv6_addr_set_v4mapped(const __be32 addr,
642 					  struct in6_addr *v4mapped)
643 {
644 	ipv6_addr_set(v4mapped,
645 			0, 0,
646 			htonl(0x0000FFFF),
647 			addr);
648 }
649 
650 /*
651  * find the first different bit between two addresses
652  * length of address must be a multiple of 32bits
653  */
654 static inline int __ipv6_addr_diff32(const void *token1, const void *token2, int addrlen)
655 {
656 	const __be32 *a1 = token1, *a2 = token2;
657 	int i;
658 
659 	addrlen >>= 2;
660 
661 	for (i = 0; i < addrlen; i++) {
662 		__be32 xb = a1[i] ^ a2[i];
663 		if (xb)
664 			return i * 32 + 31 - __fls(ntohl(xb));
665 	}
666 
667 	/*
668 	 *	we should *never* get to this point since that
669 	 *	would mean the addrs are equal
670 	 *
671 	 *	However, we do get to it 8) And exacly, when
672 	 *	addresses are equal 8)
673 	 *
674 	 *	ip route add 1111::/128 via ...
675 	 *	ip route add 1111::/64 via ...
676 	 *	and we are here.
677 	 *
678 	 *	Ideally, this function should stop comparison
679 	 *	at prefix length. It does not, but it is still OK,
680 	 *	if returned value is greater than prefix length.
681 	 *					--ANK (980803)
682 	 */
683 	return addrlen << 5;
684 }
685 
686 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
687 static inline int __ipv6_addr_diff64(const void *token1, const void *token2, int addrlen)
688 {
689 	const __be64 *a1 = token1, *a2 = token2;
690 	int i;
691 
692 	addrlen >>= 3;
693 
694 	for (i = 0; i < addrlen; i++) {
695 		__be64 xb = a1[i] ^ a2[i];
696 		if (xb)
697 			return i * 64 + 63 - __fls(be64_to_cpu(xb));
698 	}
699 
700 	return addrlen << 6;
701 }
702 #endif
703 
704 static inline int __ipv6_addr_diff(const void *token1, const void *token2, int addrlen)
705 {
706 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
707 	if (__builtin_constant_p(addrlen) && !(addrlen & 7))
708 		return __ipv6_addr_diff64(token1, token2, addrlen);
709 #endif
710 	return __ipv6_addr_diff32(token1, token2, addrlen);
711 }
712 
713 static inline int ipv6_addr_diff(const struct in6_addr *a1, const struct in6_addr *a2)
714 {
715 	return __ipv6_addr_diff(a1, a2, sizeof(struct in6_addr));
716 }
717 
718 __be32 ipv6_select_ident(struct net *net,
719 			 const struct in6_addr *daddr,
720 			 const struct in6_addr *saddr);
721 void ipv6_proxy_select_ident(struct net *net, struct sk_buff *skb);
722 
723 int ip6_dst_hoplimit(struct dst_entry *dst);
724 
725 static inline int ip6_sk_dst_hoplimit(struct ipv6_pinfo *np, struct flowi6 *fl6,
726 				      struct dst_entry *dst)
727 {
728 	int hlimit;
729 
730 	if (ipv6_addr_is_multicast(&fl6->daddr))
731 		hlimit = np->mcast_hops;
732 	else
733 		hlimit = np->hop_limit;
734 	if (hlimit < 0)
735 		hlimit = ip6_dst_hoplimit(dst);
736 	return hlimit;
737 }
738 
739 /* copy IPv6 saddr & daddr to flow_keys, possibly using 64bit load/store
740  * Equivalent to :	flow->v6addrs.src = iph->saddr;
741  *			flow->v6addrs.dst = iph->daddr;
742  */
743 static inline void iph_to_flow_copy_v6addrs(struct flow_keys *flow,
744 					    const struct ipv6hdr *iph)
745 {
746 	BUILD_BUG_ON(offsetof(typeof(flow->addrs), v6addrs.dst) !=
747 		     offsetof(typeof(flow->addrs), v6addrs.src) +
748 		     sizeof(flow->addrs.v6addrs.src));
749 	memcpy(&flow->addrs.v6addrs, &iph->saddr, sizeof(flow->addrs.v6addrs));
750 	flow->control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
751 }
752 
753 #if IS_ENABLED(CONFIG_IPV6)
754 
755 /* Sysctl settings for net ipv6.auto_flowlabels */
756 #define IP6_AUTO_FLOW_LABEL_OFF		0
757 #define IP6_AUTO_FLOW_LABEL_OPTOUT	1
758 #define IP6_AUTO_FLOW_LABEL_OPTIN	2
759 #define IP6_AUTO_FLOW_LABEL_FORCED	3
760 
761 #define IP6_AUTO_FLOW_LABEL_MAX		IP6_AUTO_FLOW_LABEL_FORCED
762 
763 #define IP6_DEFAULT_AUTO_FLOW_LABELS	IP6_AUTO_FLOW_LABEL_OPTOUT
764 
765 static inline __be32 ip6_make_flowlabel(struct net *net, struct sk_buff *skb,
766 					__be32 flowlabel, bool autolabel,
767 					struct flowi6 *fl6)
768 {
769 	u32 hash;
770 
771 	if (flowlabel ||
772 	    net->ipv6.sysctl.auto_flowlabels == IP6_AUTO_FLOW_LABEL_OFF ||
773 	    (!autolabel &&
774 	     net->ipv6.sysctl.auto_flowlabels != IP6_AUTO_FLOW_LABEL_FORCED))
775 		return flowlabel;
776 
777 	hash = skb_get_hash_flowi6(skb, fl6);
778 
779 	/* Since this is being sent on the wire obfuscate hash a bit
780 	 * to minimize possbility that any useful information to an
781 	 * attacker is leaked. Only lower 20 bits are relevant.
782 	 */
783 	rol32(hash, 16);
784 
785 	flowlabel = (__force __be32)hash & IPV6_FLOWLABEL_MASK;
786 
787 	if (net->ipv6.sysctl.flowlabel_state_ranges)
788 		flowlabel |= IPV6_FLOWLABEL_STATELESS_FLAG;
789 
790 	return flowlabel;
791 }
792 
793 static inline int ip6_default_np_autolabel(struct net *net)
794 {
795 	switch (net->ipv6.sysctl.auto_flowlabels) {
796 	case IP6_AUTO_FLOW_LABEL_OFF:
797 	case IP6_AUTO_FLOW_LABEL_OPTIN:
798 	default:
799 		return 0;
800 	case IP6_AUTO_FLOW_LABEL_OPTOUT:
801 	case IP6_AUTO_FLOW_LABEL_FORCED:
802 		return 1;
803 	}
804 }
805 #else
806 static inline void ip6_set_txhash(struct sock *sk) { }
807 static inline __be32 ip6_make_flowlabel(struct net *net, struct sk_buff *skb,
808 					__be32 flowlabel, bool autolabel,
809 					struct flowi6 *fl6)
810 {
811 	return flowlabel;
812 }
813 static inline int ip6_default_np_autolabel(struct net *net)
814 {
815 	return 0;
816 }
817 #endif
818 
819 
820 /*
821  *	Header manipulation
822  */
823 static inline void ip6_flow_hdr(struct ipv6hdr *hdr, unsigned int tclass,
824 				__be32 flowlabel)
825 {
826 	*(__be32 *)hdr = htonl(0x60000000 | (tclass << 20)) | flowlabel;
827 }
828 
829 static inline __be32 ip6_flowinfo(const struct ipv6hdr *hdr)
830 {
831 	return *(__be32 *)hdr & IPV6_FLOWINFO_MASK;
832 }
833 
834 static inline __be32 ip6_flowlabel(const struct ipv6hdr *hdr)
835 {
836 	return *(__be32 *)hdr & IPV6_FLOWLABEL_MASK;
837 }
838 
839 static inline u8 ip6_tclass(__be32 flowinfo)
840 {
841 	return ntohl(flowinfo & IPV6_TCLASS_MASK) >> IPV6_TCLASS_SHIFT;
842 }
843 
844 static inline __be32 ip6_make_flowinfo(unsigned int tclass, __be32 flowlabel)
845 {
846 	return htonl(tclass << IPV6_TCLASS_SHIFT) | flowlabel;
847 }
848 
849 /*
850  *	Prototypes exported by ipv6
851  */
852 
853 /*
854  *	rcv function (called from netdevice level)
855  */
856 
857 int ipv6_rcv(struct sk_buff *skb, struct net_device *dev,
858 	     struct packet_type *pt, struct net_device *orig_dev);
859 
860 int ip6_rcv_finish(struct net *net, struct sock *sk, struct sk_buff *skb);
861 
862 /*
863  *	upper-layer output functions
864  */
865 int ip6_xmit(const struct sock *sk, struct sk_buff *skb, struct flowi6 *fl6,
866 	     struct ipv6_txoptions *opt, int tclass);
867 
868 int ip6_find_1stfragopt(struct sk_buff *skb, u8 **nexthdr);
869 
870 int ip6_append_data(struct sock *sk,
871 		    int getfrag(void *from, char *to, int offset, int len,
872 				int odd, struct sk_buff *skb),
873 		    void *from, int length, int transhdrlen,
874 		    struct ipcm6_cookie *ipc6, struct flowi6 *fl6,
875 		    struct rt6_info *rt, unsigned int flags,
876 		    const struct sockcm_cookie *sockc);
877 
878 int ip6_push_pending_frames(struct sock *sk);
879 
880 void ip6_flush_pending_frames(struct sock *sk);
881 
882 int ip6_send_skb(struct sk_buff *skb);
883 
884 struct sk_buff *__ip6_make_skb(struct sock *sk, struct sk_buff_head *queue,
885 			       struct inet_cork_full *cork,
886 			       struct inet6_cork *v6_cork);
887 struct sk_buff *ip6_make_skb(struct sock *sk,
888 			     int getfrag(void *from, char *to, int offset,
889 					 int len, int odd, struct sk_buff *skb),
890 			     void *from, int length, int transhdrlen,
891 			     struct ipcm6_cookie *ipc6, struct flowi6 *fl6,
892 			     struct rt6_info *rt, unsigned int flags,
893 			     const struct sockcm_cookie *sockc);
894 
895 static inline struct sk_buff *ip6_finish_skb(struct sock *sk)
896 {
897 	return __ip6_make_skb(sk, &sk->sk_write_queue, &inet_sk(sk)->cork,
898 			      &inet6_sk(sk)->cork);
899 }
900 
901 int ip6_dst_lookup(struct net *net, struct sock *sk, struct dst_entry **dst,
902 		   struct flowi6 *fl6);
903 struct dst_entry *ip6_dst_lookup_flow(const struct sock *sk, struct flowi6 *fl6,
904 				      const struct in6_addr *final_dst);
905 struct dst_entry *ip6_sk_dst_lookup_flow(struct sock *sk, struct flowi6 *fl6,
906 					 const struct in6_addr *final_dst);
907 struct dst_entry *ip6_blackhole_route(struct net *net,
908 				      struct dst_entry *orig_dst);
909 
910 /*
911  *	skb processing functions
912  */
913 
914 int ip6_output(struct net *net, struct sock *sk, struct sk_buff *skb);
915 int ip6_forward(struct sk_buff *skb);
916 int ip6_input(struct sk_buff *skb);
917 int ip6_mc_input(struct sk_buff *skb);
918 
919 int __ip6_local_out(struct net *net, struct sock *sk, struct sk_buff *skb);
920 int ip6_local_out(struct net *net, struct sock *sk, struct sk_buff *skb);
921 
922 /*
923  *	Extension header (options) processing
924  */
925 
926 void ipv6_push_nfrag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt,
927 			  u8 *proto, struct in6_addr **daddr_p);
928 void ipv6_push_frag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt,
929 			 u8 *proto);
930 
931 int ipv6_skip_exthdr(const struct sk_buff *, int start, u8 *nexthdrp,
932 		     __be16 *frag_offp);
933 
934 bool ipv6_ext_hdr(u8 nexthdr);
935 
936 enum {
937 	IP6_FH_F_FRAG		= (1 << 0),
938 	IP6_FH_F_AUTH		= (1 << 1),
939 	IP6_FH_F_SKIP_RH	= (1 << 2),
940 };
941 
942 /* find specified header and get offset to it */
943 int ipv6_find_hdr(const struct sk_buff *skb, unsigned int *offset, int target,
944 		  unsigned short *fragoff, int *fragflg);
945 
946 int ipv6_find_tlv(struct sk_buff *skb, int offset, int type);
947 
948 struct in6_addr *fl6_update_dst(struct flowi6 *fl6,
949 				const struct ipv6_txoptions *opt,
950 				struct in6_addr *orig);
951 
952 /*
953  *	socket options (ipv6_sockglue.c)
954  */
955 
956 int ipv6_setsockopt(struct sock *sk, int level, int optname,
957 		    char __user *optval, unsigned int optlen);
958 int ipv6_getsockopt(struct sock *sk, int level, int optname,
959 		    char __user *optval, int __user *optlen);
960 int compat_ipv6_setsockopt(struct sock *sk, int level, int optname,
961 			   char __user *optval, unsigned int optlen);
962 int compat_ipv6_getsockopt(struct sock *sk, int level, int optname,
963 			   char __user *optval, int __user *optlen);
964 
965 int ip6_datagram_connect(struct sock *sk, struct sockaddr *addr, int addr_len);
966 int ip6_datagram_connect_v6_only(struct sock *sk, struct sockaddr *addr,
967 				 int addr_len);
968 int ip6_datagram_dst_update(struct sock *sk, bool fix_sk_saddr);
969 void ip6_datagram_release_cb(struct sock *sk);
970 
971 int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len,
972 		    int *addr_len);
973 int ipv6_recv_rxpmtu(struct sock *sk, struct msghdr *msg, int len,
974 		     int *addr_len);
975 void ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err, __be16 port,
976 		     u32 info, u8 *payload);
977 void ipv6_local_error(struct sock *sk, int err, struct flowi6 *fl6, u32 info);
978 void ipv6_local_rxpmtu(struct sock *sk, struct flowi6 *fl6, u32 mtu);
979 
980 int inet6_release(struct socket *sock);
981 int inet6_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len);
982 int inet6_getname(struct socket *sock, struct sockaddr *uaddr, int *uaddr_len,
983 		  int peer);
984 int inet6_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg);
985 
986 int inet6_hash_connect(struct inet_timewait_death_row *death_row,
987 			      struct sock *sk);
988 
989 /*
990  * reassembly.c
991  */
992 extern const struct proto_ops inet6_stream_ops;
993 extern const struct proto_ops inet6_dgram_ops;
994 
995 struct group_source_req;
996 struct group_filter;
997 
998 int ip6_mc_source(int add, int omode, struct sock *sk,
999 		  struct group_source_req *pgsr);
1000 int ip6_mc_msfilter(struct sock *sk, struct group_filter *gsf);
1001 int ip6_mc_msfget(struct sock *sk, struct group_filter *gsf,
1002 		  struct group_filter __user *optval, int __user *optlen);
1003 
1004 #ifdef CONFIG_PROC_FS
1005 int ac6_proc_init(struct net *net);
1006 void ac6_proc_exit(struct net *net);
1007 int raw6_proc_init(void);
1008 void raw6_proc_exit(void);
1009 int tcp6_proc_init(struct net *net);
1010 void tcp6_proc_exit(struct net *net);
1011 int udp6_proc_init(struct net *net);
1012 void udp6_proc_exit(struct net *net);
1013 int udplite6_proc_init(void);
1014 void udplite6_proc_exit(void);
1015 int ipv6_misc_proc_init(void);
1016 void ipv6_misc_proc_exit(void);
1017 int snmp6_register_dev(struct inet6_dev *idev);
1018 int snmp6_unregister_dev(struct inet6_dev *idev);
1019 
1020 #else
1021 static inline int ac6_proc_init(struct net *net) { return 0; }
1022 static inline void ac6_proc_exit(struct net *net) { }
1023 static inline int snmp6_register_dev(struct inet6_dev *idev) { return 0; }
1024 static inline int snmp6_unregister_dev(struct inet6_dev *idev) { return 0; }
1025 #endif
1026 
1027 #ifdef CONFIG_SYSCTL
1028 extern struct ctl_table ipv6_route_table_template[];
1029 
1030 struct ctl_table *ipv6_icmp_sysctl_init(struct net *net);
1031 struct ctl_table *ipv6_route_sysctl_init(struct net *net);
1032 int ipv6_sysctl_register(void);
1033 void ipv6_sysctl_unregister(void);
1034 #endif
1035 
1036 int ipv6_sock_mc_join(struct sock *sk, int ifindex,
1037 		      const struct in6_addr *addr);
1038 int ipv6_sock_mc_drop(struct sock *sk, int ifindex,
1039 		      const struct in6_addr *addr);
1040 #endif /* _NET_IPV6_H */
1041