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