xref: /linux/include/net/ipv6.h (revision 1a9239bb4253f9076b5b4b2a1a4e8d7defd77a95)
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  *	Linux INET6 implementation
4  *
5  *	Authors:
6  *	Pedro Roque		<roque@di.fc.ul.pt>
7  */
8 
9 #ifndef _NET_IPV6_H
10 #define _NET_IPV6_H
11 
12 #include <linux/ipv6.h>
13 #include <linux/hardirq.h>
14 #include <linux/jhash.h>
15 #include <linux/refcount.h>
16 #include <linux/jump_label_ratelimit.h>
17 #include <net/if_inet6.h>
18 #include <net/flow.h>
19 #include <net/flow_dissector.h>
20 #include <net/inet_dscp.h>
21 #include <net/snmp.h>
22 #include <net/netns/hash.h>
23 
24 struct ip_tunnel_info;
25 
26 #define SIN6_LEN_RFC2133	24
27 
28 #define IPV6_MAXPLEN		65535
29 
30 /*
31  *	NextHeader field of IPv6 header
32  */
33 
34 #define NEXTHDR_HOP		0	/* Hop-by-hop option header. */
35 #define NEXTHDR_IPV4		4	/* IPv4 in IPv6 */
36 #define NEXTHDR_TCP		6	/* TCP segment. */
37 #define NEXTHDR_UDP		17	/* UDP message. */
38 #define NEXTHDR_IPV6		41	/* IPv6 in IPv6 */
39 #define NEXTHDR_ROUTING		43	/* Routing header. */
40 #define NEXTHDR_FRAGMENT	44	/* Fragmentation/reassembly header. */
41 #define NEXTHDR_GRE		47	/* GRE header. */
42 #define NEXTHDR_ESP		50	/* Encapsulating security payload. */
43 #define NEXTHDR_AUTH		51	/* Authentication header. */
44 #define NEXTHDR_ICMP		58	/* ICMP for IPv6. */
45 #define NEXTHDR_NONE		59	/* No next header */
46 #define NEXTHDR_DEST		60	/* Destination options header. */
47 #define NEXTHDR_SCTP		132	/* SCTP message. */
48 #define NEXTHDR_MOBILITY	135	/* Mobility header. */
49 
50 #define NEXTHDR_MAX		255
51 
52 #define IPV6_DEFAULT_HOPLIMIT   64
53 #define IPV6_DEFAULT_MCASTHOPS	1
54 
55 /* Limits on Hop-by-Hop and Destination options.
56  *
57  * Per RFC8200 there is no limit on the maximum number or lengths of options in
58  * Hop-by-Hop or Destination options other then the packet must fit in an MTU.
59  * We allow configurable limits in order to mitigate potential denial of
60  * service attacks.
61  *
62  * There are three limits that may be set:
63  *   - Limit the number of options in a Hop-by-Hop or Destination options
64  *     extension header
65  *   - Limit the byte length of a Hop-by-Hop or Destination options extension
66  *     header
67  *   - Disallow unknown options
68  *
69  * The limits are expressed in corresponding sysctls:
70  *
71  * ipv6.sysctl.max_dst_opts_cnt
72  * ipv6.sysctl.max_hbh_opts_cnt
73  * ipv6.sysctl.max_dst_opts_len
74  * ipv6.sysctl.max_hbh_opts_len
75  *
76  * max_*_opts_cnt is the number of TLVs that are allowed for Destination
77  * options or Hop-by-Hop options. If the number is less than zero then unknown
78  * TLVs are disallowed and the number of known options that are allowed is the
79  * absolute value. Setting the value to INT_MAX indicates no limit.
80  *
81  * max_*_opts_len is the length limit in bytes of a Destination or
82  * Hop-by-Hop options extension header. Setting the value to INT_MAX
83  * indicates no length limit.
84  *
85  * If a limit is exceeded when processing an extension header the packet is
86  * silently discarded.
87  */
88 
89 /* Default limits for Hop-by-Hop and Destination options */
90 #define IP6_DEFAULT_MAX_DST_OPTS_CNT	 8
91 #define IP6_DEFAULT_MAX_HBH_OPTS_CNT	 8
92 #define IP6_DEFAULT_MAX_DST_OPTS_LEN	 INT_MAX /* No limit */
93 #define IP6_DEFAULT_MAX_HBH_OPTS_LEN	 INT_MAX /* No limit */
94 
95 /*
96  *	Addr type
97  *
98  *	type	-	unicast | multicast
99  *	scope	-	local	| site	    | global
100  *	v4	-	compat
101  *	v4mapped
102  *	any
103  *	loopback
104  */
105 
106 #define IPV6_ADDR_ANY		0x0000U
107 
108 #define IPV6_ADDR_UNICAST	0x0001U
109 #define IPV6_ADDR_MULTICAST	0x0002U
110 
111 #define IPV6_ADDR_LOOPBACK	0x0010U
112 #define IPV6_ADDR_LINKLOCAL	0x0020U
113 #define IPV6_ADDR_SITELOCAL	0x0040U
114 
115 #define IPV6_ADDR_COMPATv4	0x0080U
116 
117 #define IPV6_ADDR_SCOPE_MASK	0x00f0U
118 
119 #define IPV6_ADDR_MAPPED	0x1000U
120 
121 /*
122  *	Addr scopes
123  */
124 #define IPV6_ADDR_MC_SCOPE(a)	\
125 	((a)->s6_addr[1] & 0x0f)	/* nonstandard */
126 #define __IPV6_ADDR_SCOPE_INVALID	-1
127 #define IPV6_ADDR_SCOPE_NODELOCAL	0x01
128 #define IPV6_ADDR_SCOPE_LINKLOCAL	0x02
129 #define IPV6_ADDR_SCOPE_SITELOCAL	0x05
130 #define IPV6_ADDR_SCOPE_ORGLOCAL	0x08
131 #define IPV6_ADDR_SCOPE_GLOBAL		0x0e
132 
133 /*
134  *	Addr flags
135  */
136 #define IPV6_ADDR_MC_FLAG_TRANSIENT(a)	\
137 	((a)->s6_addr[1] & 0x10)
138 #define IPV6_ADDR_MC_FLAG_PREFIX(a)	\
139 	((a)->s6_addr[1] & 0x20)
140 #define IPV6_ADDR_MC_FLAG_RENDEZVOUS(a)	\
141 	((a)->s6_addr[1] & 0x40)
142 
143 /*
144  *	fragmentation header
145  */
146 
147 struct frag_hdr {
148 	__u8	nexthdr;
149 	__u8	reserved;
150 	__be16	frag_off;
151 	__be32	identification;
152 };
153 
154 /*
155  * Jumbo payload option, as described in RFC 2675 2.
156  */
157 struct hop_jumbo_hdr {
158 	u8	nexthdr;
159 	u8	hdrlen;
160 	u8	tlv_type;	/* IPV6_TLV_JUMBO, 0xC2 */
161 	u8	tlv_len;	/* 4 */
162 	__be32	jumbo_payload_len;
163 };
164 
165 #define	IP6_MF		0x0001
166 #define	IP6_OFFSET	0xFFF8
167 
168 struct ip6_fraglist_iter {
169 	struct ipv6hdr	*tmp_hdr;
170 	struct sk_buff	*frag;
171 	int		offset;
172 	unsigned int	hlen;
173 	__be32		frag_id;
174 	u8		nexthdr;
175 };
176 
177 int ip6_fraglist_init(struct sk_buff *skb, unsigned int hlen, u8 *prevhdr,
178 		      u8 nexthdr, __be32 frag_id,
179 		      struct ip6_fraglist_iter *iter);
180 void ip6_fraglist_prepare(struct sk_buff *skb, struct ip6_fraglist_iter *iter);
181 
ip6_fraglist_next(struct ip6_fraglist_iter * iter)182 static inline struct sk_buff *ip6_fraglist_next(struct ip6_fraglist_iter *iter)
183 {
184 	struct sk_buff *skb = iter->frag;
185 
186 	iter->frag = skb->next;
187 	skb_mark_not_on_list(skb);
188 
189 	return skb;
190 }
191 
192 struct ip6_frag_state {
193 	u8		*prevhdr;
194 	unsigned int	hlen;
195 	unsigned int	mtu;
196 	unsigned int	left;
197 	int		offset;
198 	int		ptr;
199 	int		hroom;
200 	int		troom;
201 	__be32		frag_id;
202 	u8		nexthdr;
203 };
204 
205 void ip6_frag_init(struct sk_buff *skb, unsigned int hlen, unsigned int mtu,
206 		   unsigned short needed_tailroom, int hdr_room, u8 *prevhdr,
207 		   u8 nexthdr, __be32 frag_id, struct ip6_frag_state *state);
208 struct sk_buff *ip6_frag_next(struct sk_buff *skb,
209 			      struct ip6_frag_state *state);
210 
211 #define IP6_REPLY_MARK(net, mark) \
212 	((net)->ipv6.sysctl.fwmark_reflect ? (mark) : 0)
213 
214 #include <net/sock.h>
215 
216 /* sysctls */
217 extern int sysctl_mld_max_msf;
218 extern int sysctl_mld_qrv;
219 
220 #define _DEVINC(net, statname, mod, idev, field)			\
221 ({									\
222 	struct inet6_dev *_idev = (idev);				\
223 	if (likely(_idev != NULL))					\
224 		mod##SNMP_INC_STATS64((_idev)->stats.statname, (field));\
225 	mod##SNMP_INC_STATS64((net)->mib.statname##_statistics, (field));\
226 })
227 
228 /* per device counters are atomic_long_t */
229 #define _DEVINCATOMIC(net, statname, mod, idev, field)			\
230 ({									\
231 	struct inet6_dev *_idev = (idev);				\
232 	if (likely(_idev != NULL))					\
233 		SNMP_INC_STATS_ATOMIC_LONG((_idev)->stats.statname##dev, (field)); \
234 	mod##SNMP_INC_STATS((net)->mib.statname##_statistics, (field));\
235 })
236 
237 /* per device and per net counters are atomic_long_t */
238 #define _DEVINC_ATOMIC_ATOMIC(net, statname, idev, field)		\
239 ({									\
240 	struct inet6_dev *_idev = (idev);				\
241 	if (likely(_idev != NULL))					\
242 		SNMP_INC_STATS_ATOMIC_LONG((_idev)->stats.statname##dev, (field)); \
243 	SNMP_INC_STATS_ATOMIC_LONG((net)->mib.statname##_statistics, (field));\
244 })
245 
246 #define _DEVADD(net, statname, mod, idev, field, val)			\
247 ({									\
248 	struct inet6_dev *_idev = (idev);				\
249 	unsigned long _field = (field);					\
250 	unsigned long _val = (val);					\
251 	if (likely(_idev != NULL))					\
252 		mod##SNMP_ADD_STATS((_idev)->stats.statname, _field,  _val); \
253 	mod##SNMP_ADD_STATS((net)->mib.statname##_statistics, _field, _val);\
254 })
255 
256 #define _DEVUPD(net, statname, mod, idev, field, val)			\
257 ({									\
258 	struct inet6_dev *_idev = (idev);				\
259 	unsigned long _val = (val);					\
260 	if (likely(_idev != NULL))					\
261 		mod##SNMP_UPD_PO_STATS((_idev)->stats.statname, field, _val); \
262 	mod##SNMP_UPD_PO_STATS((net)->mib.statname##_statistics, field, _val);\
263 })
264 
265 /* MIBs */
266 
267 #define IP6_INC_STATS(net, idev,field)		\
268 		_DEVINC(net, ipv6, , idev, field)
269 #define __IP6_INC_STATS(net, idev,field)	\
270 		_DEVINC(net, ipv6, __, idev, field)
271 #define IP6_ADD_STATS(net, idev,field,val)	\
272 		_DEVADD(net, ipv6, , idev, field, val)
273 #define __IP6_ADD_STATS(net, idev,field,val)	\
274 		_DEVADD(net, ipv6, __, idev, field, val)
275 #define IP6_UPD_PO_STATS(net, idev,field,val)   \
276 		_DEVUPD(net, ipv6, , idev, field, val)
277 #define __IP6_UPD_PO_STATS(net, idev,field,val)   \
278 		_DEVUPD(net, ipv6, __, idev, field, val)
279 #define ICMP6_INC_STATS(net, idev, field)	\
280 		_DEVINCATOMIC(net, icmpv6, , idev, field)
281 #define __ICMP6_INC_STATS(net, idev, field)	\
282 		_DEVINCATOMIC(net, icmpv6, __, idev, field)
283 
284 #define ICMP6MSGOUT_INC_STATS(net, idev, field)		\
285 	_DEVINC_ATOMIC_ATOMIC(net, icmpv6msg, idev, field +256)
286 #define ICMP6MSGIN_INC_STATS(net, idev, field)	\
287 	_DEVINC_ATOMIC_ATOMIC(net, icmpv6msg, idev, field)
288 
289 struct ip6_ra_chain {
290 	struct ip6_ra_chain	*next;
291 	struct sock		*sk;
292 	int			sel;
293 	void			(*destructor)(struct sock *);
294 };
295 
296 extern struct ip6_ra_chain	*ip6_ra_chain;
297 extern rwlock_t ip6_ra_lock;
298 
299 /*
300    This structure is prepared by protocol, when parsing
301    ancillary data and passed to IPv6.
302  */
303 
304 struct ipv6_txoptions {
305 	refcount_t		refcnt;
306 	/* Length of this structure */
307 	int			tot_len;
308 
309 	/* length of extension headers   */
310 
311 	__u16			opt_flen;	/* after fragment hdr */
312 	__u16			opt_nflen;	/* before fragment hdr */
313 
314 	struct ipv6_opt_hdr	*hopopt;
315 	struct ipv6_opt_hdr	*dst0opt;
316 	struct ipv6_rt_hdr	*srcrt;	/* Routing Header */
317 	struct ipv6_opt_hdr	*dst1opt;
318 	struct rcu_head		rcu;
319 	/* Option buffer, as read by IPV6_PKTOPTIONS, starts here. */
320 };
321 
322 /* flowlabel_reflect sysctl values */
323 enum flowlabel_reflect {
324 	FLOWLABEL_REFLECT_ESTABLISHED		= 1,
325 	FLOWLABEL_REFLECT_TCP_RESET		= 2,
326 	FLOWLABEL_REFLECT_ICMPV6_ECHO_REPLIES	= 4,
327 };
328 
329 struct ip6_flowlabel {
330 	struct ip6_flowlabel __rcu *next;
331 	__be32			label;
332 	atomic_t		users;
333 	struct in6_addr		dst;
334 	struct ipv6_txoptions	*opt;
335 	unsigned long		linger;
336 	struct rcu_head		rcu;
337 	u8			share;
338 	union {
339 		struct pid *pid;
340 		kuid_t uid;
341 	} owner;
342 	unsigned long		lastuse;
343 	unsigned long		expires;
344 	struct net		*fl_net;
345 };
346 
347 #define IPV6_FLOWINFO_MASK		cpu_to_be32(0x0FFFFFFF)
348 #define IPV6_FLOWLABEL_MASK		cpu_to_be32(0x000FFFFF)
349 #define IPV6_FLOWLABEL_STATELESS_FLAG	cpu_to_be32(0x00080000)
350 
351 #define IPV6_TCLASS_MASK (IPV6_FLOWINFO_MASK & ~IPV6_FLOWLABEL_MASK)
352 #define IPV6_TCLASS_SHIFT	20
353 
354 struct ipv6_fl_socklist {
355 	struct ipv6_fl_socklist	__rcu	*next;
356 	struct ip6_flowlabel		*fl;
357 	struct rcu_head			rcu;
358 };
359 
360 struct ipcm6_cookie {
361 	struct sockcm_cookie sockc;
362 	__s16 hlimit;
363 	__s16 tclass;
364 	__u16 gso_size;
365 	__s8  dontfrag;
366 	struct ipv6_txoptions *opt;
367 };
368 
ipcm6_init_sk(struct ipcm6_cookie * ipc6,const struct sock * sk)369 static inline void ipcm6_init_sk(struct ipcm6_cookie *ipc6,
370 				 const struct sock *sk)
371 {
372 	*ipc6 = (struct ipcm6_cookie) {
373 		.hlimit = -1,
374 		.tclass = inet6_sk(sk)->tclass,
375 		.dontfrag = inet6_test_bit(DONTFRAG, sk),
376 	};
377 
378 	sockcm_init(&ipc6->sockc, sk);
379 }
380 
txopt_get(const struct ipv6_pinfo * np)381 static inline struct ipv6_txoptions *txopt_get(const struct ipv6_pinfo *np)
382 {
383 	struct ipv6_txoptions *opt;
384 
385 	rcu_read_lock();
386 	opt = rcu_dereference(np->opt);
387 	if (opt) {
388 		if (!refcount_inc_not_zero(&opt->refcnt))
389 			opt = NULL;
390 		else
391 			opt = rcu_pointer_handoff(opt);
392 	}
393 	rcu_read_unlock();
394 	return opt;
395 }
396 
txopt_put(struct ipv6_txoptions * opt)397 static inline void txopt_put(struct ipv6_txoptions *opt)
398 {
399 	if (opt && refcount_dec_and_test(&opt->refcnt))
400 		kfree_rcu(opt, rcu);
401 }
402 
403 #if IS_ENABLED(CONFIG_IPV6)
404 struct ip6_flowlabel *__fl6_sock_lookup(struct sock *sk, __be32 label);
405 
406 extern struct static_key_false_deferred ipv6_flowlabel_exclusive;
fl6_sock_lookup(struct sock * sk,__be32 label)407 static inline struct ip6_flowlabel *fl6_sock_lookup(struct sock *sk,
408 						    __be32 label)
409 {
410 	if (static_branch_unlikely(&ipv6_flowlabel_exclusive.key) &&
411 	    READ_ONCE(sock_net(sk)->ipv6.flowlabel_has_excl))
412 		return __fl6_sock_lookup(sk, label) ? : ERR_PTR(-ENOENT);
413 
414 	return NULL;
415 }
416 #endif
417 
418 struct ipv6_txoptions *fl6_merge_options(struct ipv6_txoptions *opt_space,
419 					 struct ip6_flowlabel *fl,
420 					 struct ipv6_txoptions *fopt);
421 void fl6_free_socklist(struct sock *sk);
422 int ipv6_flowlabel_opt(struct sock *sk, sockptr_t optval, int optlen);
423 int ipv6_flowlabel_opt_get(struct sock *sk, struct in6_flowlabel_req *freq,
424 			   int flags);
425 int ip6_flowlabel_init(void);
426 void ip6_flowlabel_cleanup(void);
427 bool ip6_autoflowlabel(struct net *net, const struct sock *sk);
428 
fl6_sock_release(struct ip6_flowlabel * fl)429 static inline void fl6_sock_release(struct ip6_flowlabel *fl)
430 {
431 	if (fl)
432 		atomic_dec(&fl->users);
433 }
434 
435 enum skb_drop_reason icmpv6_notify(struct sk_buff *skb, u8 type,
436 				   u8 code, __be32 info);
437 
438 void icmpv6_push_pending_frames(struct sock *sk, struct flowi6 *fl6,
439 				struct icmp6hdr *thdr, int len);
440 
441 int ip6_ra_control(struct sock *sk, int sel);
442 
443 int ipv6_parse_hopopts(struct sk_buff *skb);
444 
445 struct ipv6_txoptions *ipv6_dup_options(struct sock *sk,
446 					struct ipv6_txoptions *opt);
447 struct ipv6_txoptions *ipv6_renew_options(struct sock *sk,
448 					  struct ipv6_txoptions *opt,
449 					  int newtype,
450 					  struct ipv6_opt_hdr *newopt);
451 struct ipv6_txoptions *__ipv6_fixup_options(struct ipv6_txoptions *opt_space,
452 					    struct ipv6_txoptions *opt);
453 
454 static inline struct ipv6_txoptions *
ipv6_fixup_options(struct ipv6_txoptions * opt_space,struct ipv6_txoptions * opt)455 ipv6_fixup_options(struct ipv6_txoptions *opt_space, struct ipv6_txoptions *opt)
456 {
457 	if (!opt)
458 		return NULL;
459 	return __ipv6_fixup_options(opt_space, opt);
460 }
461 
462 bool ipv6_opt_accepted(const struct sock *sk, const struct sk_buff *skb,
463 		       const struct inet6_skb_parm *opt);
464 struct ipv6_txoptions *ipv6_update_options(struct sock *sk,
465 					   struct ipv6_txoptions *opt);
466 
467 /* This helper is specialized for BIG TCP needs.
468  * It assumes the hop_jumbo_hdr will immediately follow the IPV6 header.
469  * It assumes headers are already in skb->head.
470  * Returns: 0, or IPPROTO_TCP if a BIG TCP packet is there.
471  */
ipv6_has_hopopt_jumbo(const struct sk_buff * skb)472 static inline int ipv6_has_hopopt_jumbo(const struct sk_buff *skb)
473 {
474 	const struct hop_jumbo_hdr *jhdr;
475 	const struct ipv6hdr *nhdr;
476 
477 	if (likely(skb->len <= GRO_LEGACY_MAX_SIZE))
478 		return 0;
479 
480 	if (skb->protocol != htons(ETH_P_IPV6))
481 		return 0;
482 
483 	if (skb_network_offset(skb) +
484 	    sizeof(struct ipv6hdr) +
485 	    sizeof(struct hop_jumbo_hdr) > skb_headlen(skb))
486 		return 0;
487 
488 	nhdr = ipv6_hdr(skb);
489 
490 	if (nhdr->nexthdr != NEXTHDR_HOP)
491 		return 0;
492 
493 	jhdr = (const struct hop_jumbo_hdr *) (nhdr + 1);
494 	if (jhdr->tlv_type != IPV6_TLV_JUMBO || jhdr->hdrlen != 0 ||
495 	    jhdr->nexthdr != IPPROTO_TCP)
496 		return 0;
497 	return jhdr->nexthdr;
498 }
499 
500 /* Return 0 if HBH header is successfully removed
501  * Or if HBH removal is unnecessary (packet is not big TCP)
502  * Return error to indicate dropping the packet
503  */
ipv6_hopopt_jumbo_remove(struct sk_buff * skb)504 static inline int ipv6_hopopt_jumbo_remove(struct sk_buff *skb)
505 {
506 	const int hophdr_len = sizeof(struct hop_jumbo_hdr);
507 	int nexthdr = ipv6_has_hopopt_jumbo(skb);
508 	struct ipv6hdr *h6;
509 
510 	if (!nexthdr)
511 		return 0;
512 
513 	if (skb_cow_head(skb, 0))
514 		return -1;
515 
516 	/* Remove the HBH header.
517 	 * Layout: [Ethernet header][IPv6 header][HBH][L4 Header]
518 	 */
519 	memmove(skb_mac_header(skb) + hophdr_len, skb_mac_header(skb),
520 		skb_network_header(skb) - skb_mac_header(skb) +
521 		sizeof(struct ipv6hdr));
522 
523 	__skb_pull(skb, hophdr_len);
524 	skb->network_header += hophdr_len;
525 	skb->mac_header += hophdr_len;
526 
527 	h6 = ipv6_hdr(skb);
528 	h6->nexthdr = nexthdr;
529 
530 	return 0;
531 }
532 
ipv6_accept_ra(const struct inet6_dev * idev)533 static inline bool ipv6_accept_ra(const struct inet6_dev *idev)
534 {
535 	s32 accept_ra = READ_ONCE(idev->cnf.accept_ra);
536 
537 	/* If forwarding is enabled, RA are not accepted unless the special
538 	 * hybrid mode (accept_ra=2) is enabled.
539 	 */
540 	return READ_ONCE(idev->cnf.forwarding) ? accept_ra == 2 :
541 		accept_ra;
542 }
543 
544 #define IPV6_FRAG_HIGH_THRESH	(4 * 1024*1024)	/* 4194304 */
545 #define IPV6_FRAG_LOW_THRESH	(3 * 1024*1024)	/* 3145728 */
546 #define IPV6_FRAG_TIMEOUT	(60 * HZ)	/* 60 seconds */
547 
548 int __ipv6_addr_type(const struct in6_addr *addr);
ipv6_addr_type(const struct in6_addr * addr)549 static inline int ipv6_addr_type(const struct in6_addr *addr)
550 {
551 	return __ipv6_addr_type(addr) & 0xffff;
552 }
553 
ipv6_addr_scope(const struct in6_addr * addr)554 static inline int ipv6_addr_scope(const struct in6_addr *addr)
555 {
556 	return __ipv6_addr_type(addr) & IPV6_ADDR_SCOPE_MASK;
557 }
558 
__ipv6_addr_src_scope(int type)559 static inline int __ipv6_addr_src_scope(int type)
560 {
561 	return (type == IPV6_ADDR_ANY) ? __IPV6_ADDR_SCOPE_INVALID : (type >> 16);
562 }
563 
ipv6_addr_src_scope(const struct in6_addr * addr)564 static inline int ipv6_addr_src_scope(const struct in6_addr *addr)
565 {
566 	return __ipv6_addr_src_scope(__ipv6_addr_type(addr));
567 }
568 
__ipv6_addr_needs_scope_id(int type)569 static inline bool __ipv6_addr_needs_scope_id(int type)
570 {
571 	return type & IPV6_ADDR_LINKLOCAL ||
572 	       (type & IPV6_ADDR_MULTICAST &&
573 		(type & (IPV6_ADDR_LOOPBACK|IPV6_ADDR_LINKLOCAL)));
574 }
575 
ipv6_iface_scope_id(const struct in6_addr * addr,int iface)576 static inline __u32 ipv6_iface_scope_id(const struct in6_addr *addr, int iface)
577 {
578 	return __ipv6_addr_needs_scope_id(__ipv6_addr_type(addr)) ? iface : 0;
579 }
580 
ipv6_addr_cmp(const struct in6_addr * a1,const struct in6_addr * a2)581 static inline int ipv6_addr_cmp(const struct in6_addr *a1, const struct in6_addr *a2)
582 {
583 	return memcmp(a1, a2, sizeof(struct in6_addr));
584 }
585 
586 static inline bool
ipv6_masked_addr_cmp(const struct in6_addr * a1,const struct in6_addr * m,const struct in6_addr * a2)587 ipv6_masked_addr_cmp(const struct in6_addr *a1, const struct in6_addr *m,
588 		     const struct in6_addr *a2)
589 {
590 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
591 	const unsigned long *ul1 = (const unsigned long *)a1;
592 	const unsigned long *ulm = (const unsigned long *)m;
593 	const unsigned long *ul2 = (const unsigned long *)a2;
594 
595 	return !!(((ul1[0] ^ ul2[0]) & ulm[0]) |
596 		  ((ul1[1] ^ ul2[1]) & ulm[1]));
597 #else
598 	return !!(((a1->s6_addr32[0] ^ a2->s6_addr32[0]) & m->s6_addr32[0]) |
599 		  ((a1->s6_addr32[1] ^ a2->s6_addr32[1]) & m->s6_addr32[1]) |
600 		  ((a1->s6_addr32[2] ^ a2->s6_addr32[2]) & m->s6_addr32[2]) |
601 		  ((a1->s6_addr32[3] ^ a2->s6_addr32[3]) & m->s6_addr32[3]));
602 #endif
603 }
604 
ipv6_addr_prefix(struct in6_addr * pfx,const struct in6_addr * addr,int plen)605 static inline void ipv6_addr_prefix(struct in6_addr *pfx,
606 				    const struct in6_addr *addr,
607 				    int plen)
608 {
609 	/* caller must guarantee 0 <= plen <= 128 */
610 	int o = plen >> 3,
611 	    b = plen & 0x7;
612 
613 	memset(pfx->s6_addr, 0, sizeof(pfx->s6_addr));
614 	memcpy(pfx->s6_addr, addr, o);
615 	if (b != 0)
616 		pfx->s6_addr[o] = addr->s6_addr[o] & (0xff00 >> b);
617 }
618 
ipv6_addr_prefix_copy(struct in6_addr * addr,const struct in6_addr * pfx,int plen)619 static inline void ipv6_addr_prefix_copy(struct in6_addr *addr,
620 					 const struct in6_addr *pfx,
621 					 int plen)
622 {
623 	/* caller must guarantee 0 <= plen <= 128 */
624 	int o = plen >> 3,
625 	    b = plen & 0x7;
626 
627 	memcpy(addr->s6_addr, pfx, o);
628 	if (b != 0) {
629 		addr->s6_addr[o] &= ~(0xff00 >> b);
630 		addr->s6_addr[o] |= (pfx->s6_addr[o] & (0xff00 >> b));
631 	}
632 }
633 
__ipv6_addr_set_half(__be32 * addr,__be32 wh,__be32 wl)634 static inline void __ipv6_addr_set_half(__be32 *addr,
635 					__be32 wh, __be32 wl)
636 {
637 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
638 #if defined(__BIG_ENDIAN)
639 	if (__builtin_constant_p(wh) && __builtin_constant_p(wl)) {
640 		*(__force u64 *)addr = ((__force u64)(wh) << 32 | (__force u64)(wl));
641 		return;
642 	}
643 #elif defined(__LITTLE_ENDIAN)
644 	if (__builtin_constant_p(wl) && __builtin_constant_p(wh)) {
645 		*(__force u64 *)addr = ((__force u64)(wl) << 32 | (__force u64)(wh));
646 		return;
647 	}
648 #endif
649 #endif
650 	addr[0] = wh;
651 	addr[1] = wl;
652 }
653 
ipv6_addr_set(struct in6_addr * addr,__be32 w1,__be32 w2,__be32 w3,__be32 w4)654 static inline void ipv6_addr_set(struct in6_addr *addr,
655 				     __be32 w1, __be32 w2,
656 				     __be32 w3, __be32 w4)
657 {
658 	__ipv6_addr_set_half(&addr->s6_addr32[0], w1, w2);
659 	__ipv6_addr_set_half(&addr->s6_addr32[2], w3, w4);
660 }
661 
ipv6_addr_equal(const struct in6_addr * a1,const struct in6_addr * a2)662 static inline bool ipv6_addr_equal(const struct in6_addr *a1,
663 				   const struct in6_addr *a2)
664 {
665 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
666 	const unsigned long *ul1 = (const unsigned long *)a1;
667 	const unsigned long *ul2 = (const unsigned long *)a2;
668 
669 	return ((ul1[0] ^ ul2[0]) | (ul1[1] ^ ul2[1])) == 0UL;
670 #else
671 	return ((a1->s6_addr32[0] ^ a2->s6_addr32[0]) |
672 		(a1->s6_addr32[1] ^ a2->s6_addr32[1]) |
673 		(a1->s6_addr32[2] ^ a2->s6_addr32[2]) |
674 		(a1->s6_addr32[3] ^ a2->s6_addr32[3])) == 0;
675 #endif
676 }
677 
678 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
__ipv6_prefix_equal64_half(const __be64 * a1,const __be64 * a2,unsigned int len)679 static inline bool __ipv6_prefix_equal64_half(const __be64 *a1,
680 					      const __be64 *a2,
681 					      unsigned int len)
682 {
683 	if (len && ((*a1 ^ *a2) & cpu_to_be64((~0UL) << (64 - len))))
684 		return false;
685 	return true;
686 }
687 
ipv6_prefix_equal(const struct in6_addr * addr1,const struct in6_addr * addr2,unsigned int prefixlen)688 static inline bool ipv6_prefix_equal(const struct in6_addr *addr1,
689 				     const struct in6_addr *addr2,
690 				     unsigned int prefixlen)
691 {
692 	const __be64 *a1 = (const __be64 *)addr1;
693 	const __be64 *a2 = (const __be64 *)addr2;
694 
695 	if (prefixlen >= 64) {
696 		if (a1[0] ^ a2[0])
697 			return false;
698 		return __ipv6_prefix_equal64_half(a1 + 1, a2 + 1, prefixlen - 64);
699 	}
700 	return __ipv6_prefix_equal64_half(a1, a2, prefixlen);
701 }
702 #else
ipv6_prefix_equal(const struct in6_addr * addr1,const struct in6_addr * addr2,unsigned int prefixlen)703 static inline bool ipv6_prefix_equal(const struct in6_addr *addr1,
704 				     const struct in6_addr *addr2,
705 				     unsigned int prefixlen)
706 {
707 	const __be32 *a1 = addr1->s6_addr32;
708 	const __be32 *a2 = addr2->s6_addr32;
709 	unsigned int pdw, pbi;
710 
711 	/* check complete u32 in prefix */
712 	pdw = prefixlen >> 5;
713 	if (pdw && memcmp(a1, a2, pdw << 2))
714 		return false;
715 
716 	/* check incomplete u32 in prefix */
717 	pbi = prefixlen & 0x1f;
718 	if (pbi && ((a1[pdw] ^ a2[pdw]) & htonl((0xffffffff) << (32 - pbi))))
719 		return false;
720 
721 	return true;
722 }
723 #endif
724 
ipv6_addr_any(const struct in6_addr * a)725 static inline bool ipv6_addr_any(const struct in6_addr *a)
726 {
727 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
728 	const unsigned long *ul = (const unsigned long *)a;
729 
730 	return (ul[0] | ul[1]) == 0UL;
731 #else
732 	return (a->s6_addr32[0] | a->s6_addr32[1] |
733 		a->s6_addr32[2] | a->s6_addr32[3]) == 0;
734 #endif
735 }
736 
ipv6_addr_hash(const struct in6_addr * a)737 static inline u32 ipv6_addr_hash(const struct in6_addr *a)
738 {
739 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
740 	const unsigned long *ul = (const unsigned long *)a;
741 	unsigned long x = ul[0] ^ ul[1];
742 
743 	return (u32)(x ^ (x >> 32));
744 #else
745 	return (__force u32)(a->s6_addr32[0] ^ a->s6_addr32[1] ^
746 			     a->s6_addr32[2] ^ a->s6_addr32[3]);
747 #endif
748 }
749 
750 /* more secured version of ipv6_addr_hash() */
__ipv6_addr_jhash(const struct in6_addr * a,const u32 initval)751 static inline u32 __ipv6_addr_jhash(const struct in6_addr *a, const u32 initval)
752 {
753 	return jhash2((__force const u32 *)a->s6_addr32,
754 		      ARRAY_SIZE(a->s6_addr32), initval);
755 }
756 
ipv6_addr_loopback(const struct in6_addr * a)757 static inline bool ipv6_addr_loopback(const struct in6_addr *a)
758 {
759 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
760 	const __be64 *be = (const __be64 *)a;
761 
762 	return (be[0] | (be[1] ^ cpu_to_be64(1))) == 0UL;
763 #else
764 	return (a->s6_addr32[0] | a->s6_addr32[1] |
765 		a->s6_addr32[2] | (a->s6_addr32[3] ^ cpu_to_be32(1))) == 0;
766 #endif
767 }
768 
769 /*
770  * Note that we must __force cast these to unsigned long to make sparse happy,
771  * since all of the endian-annotated types are fixed size regardless of arch.
772  */
ipv6_addr_v4mapped(const struct in6_addr * a)773 static inline bool ipv6_addr_v4mapped(const struct in6_addr *a)
774 {
775 	return (
776 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
777 		*(unsigned long *)a |
778 #else
779 		(__force unsigned long)(a->s6_addr32[0] | a->s6_addr32[1]) |
780 #endif
781 		(__force unsigned long)(a->s6_addr32[2] ^
782 					cpu_to_be32(0x0000ffff))) == 0UL;
783 }
784 
ipv6_addr_v4mapped_loopback(const struct in6_addr * a)785 static inline bool ipv6_addr_v4mapped_loopback(const struct in6_addr *a)
786 {
787 	return ipv6_addr_v4mapped(a) && ipv4_is_loopback(a->s6_addr32[3]);
788 }
789 
ipv6_portaddr_hash(const struct net * net,const struct in6_addr * addr6,unsigned int port)790 static inline u32 ipv6_portaddr_hash(const struct net *net,
791 				     const struct in6_addr *addr6,
792 				     unsigned int port)
793 {
794 	unsigned int hash, mix = net_hash_mix(net);
795 
796 	if (ipv6_addr_any(addr6))
797 		hash = jhash_1word(0, mix);
798 	else if (ipv6_addr_v4mapped(addr6))
799 		hash = jhash_1word((__force u32)addr6->s6_addr32[3], mix);
800 	else
801 		hash = jhash2((__force u32 *)addr6->s6_addr32, 4, mix);
802 
803 	return hash ^ port;
804 }
805 
806 /*
807  * Check for a RFC 4843 ORCHID address
808  * (Overlay Routable Cryptographic Hash Identifiers)
809  */
ipv6_addr_orchid(const struct in6_addr * a)810 static inline bool ipv6_addr_orchid(const struct in6_addr *a)
811 {
812 	return (a->s6_addr32[0] & htonl(0xfffffff0)) == htonl(0x20010010);
813 }
814 
ipv6_addr_is_multicast(const struct in6_addr * addr)815 static inline bool ipv6_addr_is_multicast(const struct in6_addr *addr)
816 {
817 	return (addr->s6_addr32[0] & htonl(0xFF000000)) == htonl(0xFF000000);
818 }
819 
ipv6_addr_set_v4mapped(const __be32 addr,struct in6_addr * v4mapped)820 static inline void ipv6_addr_set_v4mapped(const __be32 addr,
821 					  struct in6_addr *v4mapped)
822 {
823 	ipv6_addr_set(v4mapped,
824 			0, 0,
825 			htonl(0x0000FFFF),
826 			addr);
827 }
828 
829 /*
830  * find the first different bit between two addresses
831  * length of address must be a multiple of 32bits
832  */
__ipv6_addr_diff32(const void * token1,const void * token2,int addrlen)833 static inline int __ipv6_addr_diff32(const void *token1, const void *token2, int addrlen)
834 {
835 	const __be32 *a1 = token1, *a2 = token2;
836 	int i;
837 
838 	addrlen >>= 2;
839 
840 	for (i = 0; i < addrlen; i++) {
841 		__be32 xb = a1[i] ^ a2[i];
842 		if (xb)
843 			return i * 32 + 31 - __fls(ntohl(xb));
844 	}
845 
846 	/*
847 	 *	we should *never* get to this point since that
848 	 *	would mean the addrs are equal
849 	 *
850 	 *	However, we do get to it 8) And exactly, when
851 	 *	addresses are equal 8)
852 	 *
853 	 *	ip route add 1111::/128 via ...
854 	 *	ip route add 1111::/64 via ...
855 	 *	and we are here.
856 	 *
857 	 *	Ideally, this function should stop comparison
858 	 *	at prefix length. It does not, but it is still OK,
859 	 *	if returned value is greater than prefix length.
860 	 *					--ANK (980803)
861 	 */
862 	return addrlen << 5;
863 }
864 
865 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
__ipv6_addr_diff64(const void * token1,const void * token2,int addrlen)866 static inline int __ipv6_addr_diff64(const void *token1, const void *token2, int addrlen)
867 {
868 	const __be64 *a1 = token1, *a2 = token2;
869 	int i;
870 
871 	addrlen >>= 3;
872 
873 	for (i = 0; i < addrlen; i++) {
874 		__be64 xb = a1[i] ^ a2[i];
875 		if (xb)
876 			return i * 64 + 63 - __fls(be64_to_cpu(xb));
877 	}
878 
879 	return addrlen << 6;
880 }
881 #endif
882 
__ipv6_addr_diff(const void * token1,const void * token2,int addrlen)883 static inline int __ipv6_addr_diff(const void *token1, const void *token2, int addrlen)
884 {
885 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
886 	if (__builtin_constant_p(addrlen) && !(addrlen & 7))
887 		return __ipv6_addr_diff64(token1, token2, addrlen);
888 #endif
889 	return __ipv6_addr_diff32(token1, token2, addrlen);
890 }
891 
ipv6_addr_diff(const struct in6_addr * a1,const struct in6_addr * a2)892 static inline int ipv6_addr_diff(const struct in6_addr *a1, const struct in6_addr *a2)
893 {
894 	return __ipv6_addr_diff(a1, a2, sizeof(struct in6_addr));
895 }
896 
897 __be32 ipv6_select_ident(struct net *net,
898 			 const struct in6_addr *daddr,
899 			 const struct in6_addr *saddr);
900 __be32 ipv6_proxy_select_ident(struct net *net, struct sk_buff *skb);
901 
902 int ip6_dst_hoplimit(struct dst_entry *dst);
903 
ip6_sk_dst_hoplimit(struct ipv6_pinfo * np,struct flowi6 * fl6,struct dst_entry * dst)904 static inline int ip6_sk_dst_hoplimit(struct ipv6_pinfo *np, struct flowi6 *fl6,
905 				      struct dst_entry *dst)
906 {
907 	int hlimit;
908 
909 	if (ipv6_addr_is_multicast(&fl6->daddr))
910 		hlimit = READ_ONCE(np->mcast_hops);
911 	else
912 		hlimit = READ_ONCE(np->hop_limit);
913 	if (hlimit < 0)
914 		hlimit = ip6_dst_hoplimit(dst);
915 	return hlimit;
916 }
917 
918 /* copy IPv6 saddr & daddr to flow_keys, possibly using 64bit load/store
919  * Equivalent to :	flow->v6addrs.src = iph->saddr;
920  *			flow->v6addrs.dst = iph->daddr;
921  */
iph_to_flow_copy_v6addrs(struct flow_keys * flow,const struct ipv6hdr * iph)922 static inline void iph_to_flow_copy_v6addrs(struct flow_keys *flow,
923 					    const struct ipv6hdr *iph)
924 {
925 	BUILD_BUG_ON(offsetof(typeof(flow->addrs), v6addrs.dst) !=
926 		     offsetof(typeof(flow->addrs), v6addrs.src) +
927 		     sizeof(flow->addrs.v6addrs.src));
928 	memcpy(&flow->addrs.v6addrs, &iph->addrs, sizeof(flow->addrs.v6addrs));
929 	flow->control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
930 }
931 
932 #if IS_ENABLED(CONFIG_IPV6)
933 
ipv6_can_nonlocal_bind(struct net * net,struct inet_sock * inet)934 static inline bool ipv6_can_nonlocal_bind(struct net *net,
935 					  struct inet_sock *inet)
936 {
937 	return net->ipv6.sysctl.ip_nonlocal_bind ||
938 		test_bit(INET_FLAGS_FREEBIND, &inet->inet_flags) ||
939 		test_bit(INET_FLAGS_TRANSPARENT, &inet->inet_flags);
940 }
941 
942 /* Sysctl settings for net ipv6.auto_flowlabels */
943 #define IP6_AUTO_FLOW_LABEL_OFF		0
944 #define IP6_AUTO_FLOW_LABEL_OPTOUT	1
945 #define IP6_AUTO_FLOW_LABEL_OPTIN	2
946 #define IP6_AUTO_FLOW_LABEL_FORCED	3
947 
948 #define IP6_AUTO_FLOW_LABEL_MAX		IP6_AUTO_FLOW_LABEL_FORCED
949 
950 #define IP6_DEFAULT_AUTO_FLOW_LABELS	IP6_AUTO_FLOW_LABEL_OPTOUT
951 
ip6_make_flowlabel(struct net * net,struct sk_buff * skb,__be32 flowlabel,bool autolabel,struct flowi6 * fl6)952 static inline __be32 ip6_make_flowlabel(struct net *net, struct sk_buff *skb,
953 					__be32 flowlabel, bool autolabel,
954 					struct flowi6 *fl6)
955 {
956 	u32 hash;
957 
958 	/* @flowlabel may include more than a flow label, eg, the traffic class.
959 	 * Here we want only the flow label value.
960 	 */
961 	flowlabel &= IPV6_FLOWLABEL_MASK;
962 
963 	if (flowlabel ||
964 	    net->ipv6.sysctl.auto_flowlabels == IP6_AUTO_FLOW_LABEL_OFF ||
965 	    (!autolabel &&
966 	     net->ipv6.sysctl.auto_flowlabels != IP6_AUTO_FLOW_LABEL_FORCED))
967 		return flowlabel;
968 
969 	hash = skb_get_hash_flowi6(skb, fl6);
970 
971 	/* Since this is being sent on the wire obfuscate hash a bit
972 	 * to minimize possibility that any useful information to an
973 	 * attacker is leaked. Only lower 20 bits are relevant.
974 	 */
975 	hash = rol32(hash, 16);
976 
977 	flowlabel = (__force __be32)hash & IPV6_FLOWLABEL_MASK;
978 
979 	if (net->ipv6.sysctl.flowlabel_state_ranges)
980 		flowlabel |= IPV6_FLOWLABEL_STATELESS_FLAG;
981 
982 	return flowlabel;
983 }
984 
ip6_default_np_autolabel(struct net * net)985 static inline int ip6_default_np_autolabel(struct net *net)
986 {
987 	switch (net->ipv6.sysctl.auto_flowlabels) {
988 	case IP6_AUTO_FLOW_LABEL_OFF:
989 	case IP6_AUTO_FLOW_LABEL_OPTIN:
990 	default:
991 		return 0;
992 	case IP6_AUTO_FLOW_LABEL_OPTOUT:
993 	case IP6_AUTO_FLOW_LABEL_FORCED:
994 		return 1;
995 	}
996 }
997 #else
ip6_make_flowlabel(struct net * net,struct sk_buff * skb,__be32 flowlabel,bool autolabel,struct flowi6 * fl6)998 static inline __be32 ip6_make_flowlabel(struct net *net, struct sk_buff *skb,
999 					__be32 flowlabel, bool autolabel,
1000 					struct flowi6 *fl6)
1001 {
1002 	return flowlabel;
1003 }
ip6_default_np_autolabel(struct net * net)1004 static inline int ip6_default_np_autolabel(struct net *net)
1005 {
1006 	return 0;
1007 }
1008 #endif
1009 
1010 #if IS_ENABLED(CONFIG_IPV6)
ip6_multipath_hash_policy(const struct net * net)1011 static inline int ip6_multipath_hash_policy(const struct net *net)
1012 {
1013 	return net->ipv6.sysctl.multipath_hash_policy;
1014 }
ip6_multipath_hash_fields(const struct net * net)1015 static inline u32 ip6_multipath_hash_fields(const struct net *net)
1016 {
1017 	return net->ipv6.sysctl.multipath_hash_fields;
1018 }
1019 #else
ip6_multipath_hash_policy(const struct net * net)1020 static inline int ip6_multipath_hash_policy(const struct net *net)
1021 {
1022 	return 0;
1023 }
ip6_multipath_hash_fields(const struct net * net)1024 static inline u32 ip6_multipath_hash_fields(const struct net *net)
1025 {
1026 	return 0;
1027 }
1028 #endif
1029 
1030 /*
1031  *	Header manipulation
1032  */
ip6_flow_hdr(struct ipv6hdr * hdr,unsigned int tclass,__be32 flowlabel)1033 static inline void ip6_flow_hdr(struct ipv6hdr *hdr, unsigned int tclass,
1034 				__be32 flowlabel)
1035 {
1036 	*(__be32 *)hdr = htonl(0x60000000 | (tclass << 20)) | flowlabel;
1037 }
1038 
ip6_flowinfo(const struct ipv6hdr * hdr)1039 static inline __be32 ip6_flowinfo(const struct ipv6hdr *hdr)
1040 {
1041 	return *(__be32 *)hdr & IPV6_FLOWINFO_MASK;
1042 }
1043 
ip6_flowlabel(const struct ipv6hdr * hdr)1044 static inline __be32 ip6_flowlabel(const struct ipv6hdr *hdr)
1045 {
1046 	return *(__be32 *)hdr & IPV6_FLOWLABEL_MASK;
1047 }
1048 
ip6_tclass(__be32 flowinfo)1049 static inline u8 ip6_tclass(__be32 flowinfo)
1050 {
1051 	return ntohl(flowinfo & IPV6_TCLASS_MASK) >> IPV6_TCLASS_SHIFT;
1052 }
1053 
ip6_dscp(__be32 flowinfo)1054 static inline dscp_t ip6_dscp(__be32 flowinfo)
1055 {
1056 	return inet_dsfield_to_dscp(ip6_tclass(flowinfo));
1057 }
1058 
ip6_make_flowinfo(unsigned int tclass,__be32 flowlabel)1059 static inline __be32 ip6_make_flowinfo(unsigned int tclass, __be32 flowlabel)
1060 {
1061 	return htonl(tclass << IPV6_TCLASS_SHIFT) | flowlabel;
1062 }
1063 
flowi6_get_flowlabel(const struct flowi6 * fl6)1064 static inline __be32 flowi6_get_flowlabel(const struct flowi6 *fl6)
1065 {
1066 	return fl6->flowlabel & IPV6_FLOWLABEL_MASK;
1067 }
1068 
1069 /*
1070  *	Prototypes exported by ipv6
1071  */
1072 
1073 /*
1074  *	rcv function (called from netdevice level)
1075  */
1076 
1077 int ipv6_rcv(struct sk_buff *skb, struct net_device *dev,
1078 	     struct packet_type *pt, struct net_device *orig_dev);
1079 void ipv6_list_rcv(struct list_head *head, struct packet_type *pt,
1080 		   struct net_device *orig_dev);
1081 
1082 int ip6_rcv_finish(struct net *net, struct sock *sk, struct sk_buff *skb);
1083 
1084 /*
1085  *	upper-layer output functions
1086  */
1087 int ip6_xmit(const struct sock *sk, struct sk_buff *skb, struct flowi6 *fl6,
1088 	     __u32 mark, struct ipv6_txoptions *opt, int tclass, u32 priority);
1089 
1090 int ip6_find_1stfragopt(struct sk_buff *skb, u8 **nexthdr);
1091 
1092 int ip6_append_data(struct sock *sk,
1093 		    int getfrag(void *from, char *to, int offset, int len,
1094 				int odd, struct sk_buff *skb),
1095 		    void *from, size_t length, int transhdrlen,
1096 		    struct ipcm6_cookie *ipc6, struct flowi6 *fl6,
1097 		    struct rt6_info *rt, unsigned int flags);
1098 
1099 int ip6_push_pending_frames(struct sock *sk);
1100 
1101 void ip6_flush_pending_frames(struct sock *sk);
1102 
1103 int ip6_send_skb(struct sk_buff *skb);
1104 
1105 struct sk_buff *__ip6_make_skb(struct sock *sk, struct sk_buff_head *queue,
1106 			       struct inet_cork_full *cork,
1107 			       struct inet6_cork *v6_cork);
1108 struct sk_buff *ip6_make_skb(struct sock *sk,
1109 			     int getfrag(void *from, char *to, int offset,
1110 					 int len, int odd, struct sk_buff *skb),
1111 			     void *from, size_t length, int transhdrlen,
1112 			     struct ipcm6_cookie *ipc6,
1113 			     struct rt6_info *rt, unsigned int flags,
1114 			     struct inet_cork_full *cork);
1115 
ip6_finish_skb(struct sock * sk)1116 static inline struct sk_buff *ip6_finish_skb(struct sock *sk)
1117 {
1118 	return __ip6_make_skb(sk, &sk->sk_write_queue, &inet_sk(sk)->cork,
1119 			      &inet6_sk(sk)->cork);
1120 }
1121 
1122 int ip6_dst_lookup(struct net *net, struct sock *sk, struct dst_entry **dst,
1123 		   struct flowi6 *fl6);
1124 struct dst_entry *ip6_dst_lookup_flow(struct net *net, const struct sock *sk, struct flowi6 *fl6,
1125 				      const struct in6_addr *final_dst);
1126 struct dst_entry *ip6_sk_dst_lookup_flow(struct sock *sk, struct flowi6 *fl6,
1127 					 const struct in6_addr *final_dst,
1128 					 bool connected);
1129 struct dst_entry *ip6_blackhole_route(struct net *net,
1130 				      struct dst_entry *orig_dst);
1131 
1132 /*
1133  *	skb processing functions
1134  */
1135 
1136 int ip6_output(struct net *net, struct sock *sk, struct sk_buff *skb);
1137 int ip6_forward(struct sk_buff *skb);
1138 int ip6_input(struct sk_buff *skb);
1139 int ip6_mc_input(struct sk_buff *skb);
1140 void ip6_protocol_deliver_rcu(struct net *net, struct sk_buff *skb, int nexthdr,
1141 			      bool have_final);
1142 
1143 int __ip6_local_out(struct net *net, struct sock *sk, struct sk_buff *skb);
1144 int ip6_local_out(struct net *net, struct sock *sk, struct sk_buff *skb);
1145 
1146 /*
1147  *	Extension header (options) processing
1148  */
1149 
1150 void ipv6_push_nfrag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt,
1151 			  u8 *proto, struct in6_addr **daddr_p,
1152 			  struct in6_addr *saddr);
1153 void ipv6_push_frag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt,
1154 			 u8 *proto);
1155 
1156 int ipv6_skip_exthdr(const struct sk_buff *, int start, u8 *nexthdrp,
1157 		     __be16 *frag_offp);
1158 
1159 bool ipv6_ext_hdr(u8 nexthdr);
1160 
1161 enum {
1162 	IP6_FH_F_FRAG		= (1 << 0),
1163 	IP6_FH_F_AUTH		= (1 << 1),
1164 	IP6_FH_F_SKIP_RH	= (1 << 2),
1165 };
1166 
1167 /* find specified header and get offset to it */
1168 int ipv6_find_hdr(const struct sk_buff *skb, unsigned int *offset, int target,
1169 		  unsigned short *fragoff, int *fragflg);
1170 
1171 int ipv6_find_tlv(const struct sk_buff *skb, int offset, int type);
1172 
1173 struct in6_addr *fl6_update_dst(struct flowi6 *fl6,
1174 				const struct ipv6_txoptions *opt,
1175 				struct in6_addr *orig);
1176 
1177 /*
1178  *	socket options (ipv6_sockglue.c)
1179  */
1180 DECLARE_STATIC_KEY_FALSE(ip6_min_hopcount);
1181 
1182 int do_ipv6_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval,
1183 		       unsigned int optlen);
1184 int ipv6_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval,
1185 		    unsigned int optlen);
1186 int do_ipv6_getsockopt(struct sock *sk, int level, int optname,
1187 		       sockptr_t optval, sockptr_t optlen);
1188 int ipv6_getsockopt(struct sock *sk, int level, int optname,
1189 		    char __user *optval, int __user *optlen);
1190 
1191 int __ip6_datagram_connect(struct sock *sk, struct sockaddr *addr,
1192 			   int addr_len);
1193 int ip6_datagram_connect(struct sock *sk, struct sockaddr *addr, int addr_len);
1194 int ip6_datagram_connect_v6_only(struct sock *sk, struct sockaddr *addr,
1195 				 int addr_len);
1196 int ip6_datagram_dst_update(struct sock *sk, bool fix_sk_saddr);
1197 void ip6_datagram_release_cb(struct sock *sk);
1198 
1199 int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len,
1200 		    int *addr_len);
1201 int ipv6_recv_rxpmtu(struct sock *sk, struct msghdr *msg, int len,
1202 		     int *addr_len);
1203 void ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err, __be16 port,
1204 		     u32 info, u8 *payload);
1205 void ipv6_local_error(struct sock *sk, int err, struct flowi6 *fl6, u32 info);
1206 void ipv6_local_rxpmtu(struct sock *sk, struct flowi6 *fl6, u32 mtu);
1207 
1208 void inet6_cleanup_sock(struct sock *sk);
1209 void inet6_sock_destruct(struct sock *sk);
1210 int inet6_release(struct socket *sock);
1211 int inet6_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len);
1212 int inet6_bind_sk(struct sock *sk, struct sockaddr *uaddr, int addr_len);
1213 int inet6_getname(struct socket *sock, struct sockaddr *uaddr,
1214 		  int peer);
1215 int inet6_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg);
1216 int inet6_compat_ioctl(struct socket *sock, unsigned int cmd,
1217 		unsigned long arg);
1218 
1219 int inet6_hash_connect(struct inet_timewait_death_row *death_row,
1220 			      struct sock *sk);
1221 int inet6_sendmsg(struct socket *sock, struct msghdr *msg, size_t size);
1222 int inet6_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
1223 		  int flags);
1224 
1225 /*
1226  * reassembly.c
1227  */
1228 extern const struct proto_ops inet6_stream_ops;
1229 extern const struct proto_ops inet6_dgram_ops;
1230 extern const struct proto_ops inet6_sockraw_ops;
1231 
1232 struct group_source_req;
1233 struct group_filter;
1234 
1235 int ip6_mc_source(int add, int omode, struct sock *sk,
1236 		  struct group_source_req *pgsr);
1237 int ip6_mc_msfilter(struct sock *sk, struct group_filter *gsf,
1238 		  struct sockaddr_storage *list);
1239 int ip6_mc_msfget(struct sock *sk, struct group_filter *gsf,
1240 		  sockptr_t optval, size_t ss_offset);
1241 
1242 #ifdef CONFIG_PROC_FS
1243 int ac6_proc_init(struct net *net);
1244 void ac6_proc_exit(struct net *net);
1245 int raw6_proc_init(void);
1246 void raw6_proc_exit(void);
1247 int tcp6_proc_init(struct net *net);
1248 void tcp6_proc_exit(struct net *net);
1249 int udp6_proc_init(struct net *net);
1250 void udp6_proc_exit(struct net *net);
1251 int udplite6_proc_init(void);
1252 void udplite6_proc_exit(void);
1253 int ipv6_misc_proc_init(void);
1254 void ipv6_misc_proc_exit(void);
1255 int snmp6_register_dev(struct inet6_dev *idev);
1256 int snmp6_unregister_dev(struct inet6_dev *idev);
1257 
1258 #else
ac6_proc_init(struct net * net)1259 static inline int ac6_proc_init(struct net *net) { return 0; }
ac6_proc_exit(struct net * net)1260 static inline void ac6_proc_exit(struct net *net) { }
snmp6_register_dev(struct inet6_dev * idev)1261 static inline int snmp6_register_dev(struct inet6_dev *idev) { return 0; }
snmp6_unregister_dev(struct inet6_dev * idev)1262 static inline int snmp6_unregister_dev(struct inet6_dev *idev) { return 0; }
1263 #endif
1264 
1265 #ifdef CONFIG_SYSCTL
1266 struct ctl_table *ipv6_icmp_sysctl_init(struct net *net);
1267 size_t ipv6_icmp_sysctl_table_size(void);
1268 struct ctl_table *ipv6_route_sysctl_init(struct net *net);
1269 size_t ipv6_route_sysctl_table_size(struct net *net);
1270 int ipv6_sysctl_register(void);
1271 void ipv6_sysctl_unregister(void);
1272 #endif
1273 
1274 int ipv6_sock_mc_join(struct sock *sk, int ifindex,
1275 		      const struct in6_addr *addr);
1276 int ipv6_sock_mc_join_ssm(struct sock *sk, int ifindex,
1277 			  const struct in6_addr *addr, unsigned int mode);
1278 int ipv6_sock_mc_drop(struct sock *sk, int ifindex,
1279 		      const struct in6_addr *addr);
1280 
ip6_sock_set_v6only(struct sock * sk)1281 static inline int ip6_sock_set_v6only(struct sock *sk)
1282 {
1283 	if (inet_sk(sk)->inet_num)
1284 		return -EINVAL;
1285 	lock_sock(sk);
1286 	sk->sk_ipv6only = true;
1287 	release_sock(sk);
1288 	return 0;
1289 }
1290 
ip6_sock_set_recverr(struct sock * sk)1291 static inline void ip6_sock_set_recverr(struct sock *sk)
1292 {
1293 	inet6_set_bit(RECVERR6, sk);
1294 }
1295 
1296 #define IPV6_PREFER_SRC_MASK (IPV6_PREFER_SRC_TMP | IPV6_PREFER_SRC_PUBLIC | \
1297 			      IPV6_PREFER_SRC_COA)
1298 
ip6_sock_set_addr_preferences(struct sock * sk,int val)1299 static inline int ip6_sock_set_addr_preferences(struct sock *sk, int val)
1300 {
1301 	unsigned int prefmask = ~IPV6_PREFER_SRC_MASK;
1302 	unsigned int pref = 0;
1303 
1304 	/* check PUBLIC/TMP/PUBTMP_DEFAULT conflicts */
1305 	switch (val & (IPV6_PREFER_SRC_PUBLIC |
1306 		       IPV6_PREFER_SRC_TMP |
1307 		       IPV6_PREFER_SRC_PUBTMP_DEFAULT)) {
1308 	case IPV6_PREFER_SRC_PUBLIC:
1309 		pref |= IPV6_PREFER_SRC_PUBLIC;
1310 		prefmask &= ~(IPV6_PREFER_SRC_PUBLIC |
1311 			      IPV6_PREFER_SRC_TMP);
1312 		break;
1313 	case IPV6_PREFER_SRC_TMP:
1314 		pref |= IPV6_PREFER_SRC_TMP;
1315 		prefmask &= ~(IPV6_PREFER_SRC_PUBLIC |
1316 			      IPV6_PREFER_SRC_TMP);
1317 		break;
1318 	case IPV6_PREFER_SRC_PUBTMP_DEFAULT:
1319 		prefmask &= ~(IPV6_PREFER_SRC_PUBLIC |
1320 			      IPV6_PREFER_SRC_TMP);
1321 		break;
1322 	case 0:
1323 		break;
1324 	default:
1325 		return -EINVAL;
1326 	}
1327 
1328 	/* check HOME/COA conflicts */
1329 	switch (val & (IPV6_PREFER_SRC_HOME | IPV6_PREFER_SRC_COA)) {
1330 	case IPV6_PREFER_SRC_HOME:
1331 		prefmask &= ~IPV6_PREFER_SRC_COA;
1332 		break;
1333 	case IPV6_PREFER_SRC_COA:
1334 		pref |= IPV6_PREFER_SRC_COA;
1335 		break;
1336 	case 0:
1337 		break;
1338 	default:
1339 		return -EINVAL;
1340 	}
1341 
1342 	/* check CGA/NONCGA conflicts */
1343 	switch (val & (IPV6_PREFER_SRC_CGA|IPV6_PREFER_SRC_NONCGA)) {
1344 	case IPV6_PREFER_SRC_CGA:
1345 	case IPV6_PREFER_SRC_NONCGA:
1346 	case 0:
1347 		break;
1348 	default:
1349 		return -EINVAL;
1350 	}
1351 
1352 	WRITE_ONCE(inet6_sk(sk)->srcprefs,
1353 		   (READ_ONCE(inet6_sk(sk)->srcprefs) & prefmask) | pref);
1354 	return 0;
1355 }
1356 
ip6_sock_set_recvpktinfo(struct sock * sk)1357 static inline void ip6_sock_set_recvpktinfo(struct sock *sk)
1358 {
1359 	lock_sock(sk);
1360 	inet6_sk(sk)->rxopt.bits.rxinfo = true;
1361 	release_sock(sk);
1362 }
1363 
1364 #define IPV6_ADDR_WORDS 4
1365 
ipv6_addr_cpu_to_be32(__be32 * dst,const u32 * src)1366 static inline void ipv6_addr_cpu_to_be32(__be32 *dst, const u32 *src)
1367 {
1368 	cpu_to_be32_array(dst, src, IPV6_ADDR_WORDS);
1369 }
1370 
ipv6_addr_be32_to_cpu(u32 * dst,const __be32 * src)1371 static inline void ipv6_addr_be32_to_cpu(u32 *dst, const __be32 *src)
1372 {
1373 	be32_to_cpu_array(dst, src, IPV6_ADDR_WORDS);
1374 }
1375 
1376 #endif /* _NET_IPV6_H */
1377