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   1/*
   2 *	Linux INET6 implementation
   3 *
   4 *	Authors:
   5 *	Pedro Roque		<roque@di.fc.ul.pt>
   6 *
   7 *	This program is free software; you can redistribute it and/or
   8 *      modify it under the terms of the GNU General Public License
   9 *      as published by the Free Software Foundation; either version
  10 *      2 of the License, or (at your option) any later version.
  11 */
  12
  13#ifndef _NET_IPV6_H
  14#define _NET_IPV6_H
  15
  16#include <linux/ipv6.h>
  17#include <linux/hardirq.h>
  18#include <linux/jhash.h>
  19#include <net/if_inet6.h>
  20#include <net/ndisc.h>
  21#include <net/flow.h>
  22#include <net/flow_dissector.h>
  23#include <net/snmp.h>
  24
  25#define SIN6_LEN_RFC2133	24
  26
  27#define IPV6_MAXPLEN		65535
  28
  29/*
  30 *	NextHeader field of IPv6 header
  31 */
  32
  33#define NEXTHDR_HOP		0	/* Hop-by-hop option header. */
  34#define NEXTHDR_TCP		6	/* TCP segment. */
  35#define NEXTHDR_UDP		17	/* UDP message. */
  36#define NEXTHDR_IPV6		41	/* IPv6 in IPv6 */
  37#define NEXTHDR_ROUTING		43	/* Routing header. */
  38#define NEXTHDR_FRAGMENT	44	/* Fragmentation/reassembly header. */
  39#define NEXTHDR_GRE		47	/* GRE header. */
  40#define NEXTHDR_ESP		50	/* Encapsulating security payload. */
  41#define NEXTHDR_AUTH		51	/* Authentication header. */
  42#define NEXTHDR_ICMP		58	/* ICMP for IPv6. */
  43#define NEXTHDR_NONE		59	/* No next header */
  44#define NEXTHDR_DEST		60	/* Destination options header. */
  45#define NEXTHDR_SCTP		132	/* SCTP message. */
  46#define NEXTHDR_MOBILITY	135	/* Mobility header. */
  47
  48#define NEXTHDR_MAX		255
  49
  50#define IPV6_DEFAULT_HOPLIMIT   64
  51#define IPV6_DEFAULT_MCASTHOPS	1
  52
  53/*
  54 *	Addr type
  55 *	
  56 *	type	-	unicast | multicast
  57 *	scope	-	local	| site	    | global
  58 *	v4	-	compat
  59 *	v4mapped
  60 *	any
  61 *	loopback
  62 */
  63
  64#define IPV6_ADDR_ANY		0x0000U
  65
  66#define IPV6_ADDR_UNICAST      	0x0001U	
  67#define IPV6_ADDR_MULTICAST    	0x0002U	
  68
  69#define IPV6_ADDR_LOOPBACK	0x0010U
  70#define IPV6_ADDR_LINKLOCAL	0x0020U
  71#define IPV6_ADDR_SITELOCAL	0x0040U
  72
  73#define IPV6_ADDR_COMPATv4	0x0080U
  74
  75#define IPV6_ADDR_SCOPE_MASK	0x00f0U
  76
  77#define IPV6_ADDR_MAPPED	0x1000U
  78
  79/*
  80 *	Addr scopes
  81 */
  82#define IPV6_ADDR_MC_SCOPE(a)	\
  83	((a)->s6_addr[1] & 0x0f)	/* nonstandard */
  84#define __IPV6_ADDR_SCOPE_INVALID	-1
  85#define IPV6_ADDR_SCOPE_NODELOCAL	0x01
  86#define IPV6_ADDR_SCOPE_LINKLOCAL	0x02
  87#define IPV6_ADDR_SCOPE_SITELOCAL	0x05
  88#define IPV6_ADDR_SCOPE_ORGLOCAL	0x08
  89#define IPV6_ADDR_SCOPE_GLOBAL		0x0e
  90
  91/*
  92 *	Addr flags
  93 */
  94#define IPV6_ADDR_MC_FLAG_TRANSIENT(a)	\
  95	((a)->s6_addr[1] & 0x10)
  96#define IPV6_ADDR_MC_FLAG_PREFIX(a)	\
  97	((a)->s6_addr[1] & 0x20)
  98#define IPV6_ADDR_MC_FLAG_RENDEZVOUS(a)	\
  99	((a)->s6_addr[1] & 0x40)
 100
 101/*
 102 *	fragmentation header
 103 */
 104
 105struct frag_hdr {
 106	__u8	nexthdr;
 107	__u8	reserved;
 108	__be16	frag_off;
 109	__be32	identification;
 110};
 111
 112#define	IP6_MF		0x0001
 113#define	IP6_OFFSET	0xFFF8
 114
 115#define IP6_REPLY_MARK(net, mark) \
 116	((net)->ipv6.sysctl.fwmark_reflect ? (mark) : 0)
 117
 118#include <net/sock.h>
 119
 120/* sysctls */
 121extern int sysctl_mld_max_msf;
 122extern int sysctl_mld_qrv;
 123
 124#define _DEVINC(net, statname, modifier, idev, field)			\
 125({									\
 126	struct inet6_dev *_idev = (idev);				\
 127	if (likely(_idev != NULL))					\
 128		SNMP_INC_STATS##modifier((_idev)->stats.statname, (field)); \
 129	SNMP_INC_STATS##modifier((net)->mib.statname##_statistics, (field));\
 130})
 131
 132/* per device counters are atomic_long_t */
 133#define _DEVINCATOMIC(net, statname, modifier, idev, field)		\
 134({									\
 135	struct inet6_dev *_idev = (idev);				\
 136	if (likely(_idev != NULL))					\
 137		SNMP_INC_STATS_ATOMIC_LONG((_idev)->stats.statname##dev, (field)); \
 138	SNMP_INC_STATS##modifier((net)->mib.statname##_statistics, (field));\
 139})
 140
 141/* per device and per net counters are atomic_long_t */
 142#define _DEVINC_ATOMIC_ATOMIC(net, statname, idev, field)		\
 143({									\
 144	struct inet6_dev *_idev = (idev);				\
 145	if (likely(_idev != NULL))					\
 146		SNMP_INC_STATS_ATOMIC_LONG((_idev)->stats.statname##dev, (field)); \
 147	SNMP_INC_STATS_ATOMIC_LONG((net)->mib.statname##_statistics, (field));\
 148})
 149
 150#define _DEVADD(net, statname, modifier, idev, field, val)		\
 151({									\
 152	struct inet6_dev *_idev = (idev);				\
 153	if (likely(_idev != NULL))					\
 154		SNMP_ADD_STATS##modifier((_idev)->stats.statname, (field), (val)); \
 155	SNMP_ADD_STATS##modifier((net)->mib.statname##_statistics, (field), (val));\
 156})
 157
 158#define _DEVUPD(net, statname, modifier, idev, field, val)		\
 159({									\
 160	struct inet6_dev *_idev = (idev);				\
 161	if (likely(_idev != NULL))					\
 162		SNMP_UPD_PO_STATS##modifier((_idev)->stats.statname, field, (val)); \
 163	SNMP_UPD_PO_STATS##modifier((net)->mib.statname##_statistics, field, (val));\
 164})
 165
 166/* MIBs */
 167
 168#define IP6_INC_STATS(net, idev,field)		\
 169		_DEVINC(net, ipv6, 64, idev, field)
 170#define IP6_INC_STATS_BH(net, idev,field)	\
 171		_DEVINC(net, ipv6, 64_BH, idev, field)
 172#define IP6_ADD_STATS(net, idev,field,val)	\
 173		_DEVADD(net, ipv6, 64, idev, field, val)
 174#define IP6_ADD_STATS_BH(net, idev,field,val)	\
 175		_DEVADD(net, ipv6, 64_BH, idev, field, val)
 176#define IP6_UPD_PO_STATS(net, idev,field,val)   \
 177		_DEVUPD(net, ipv6, 64, idev, field, val)
 178#define IP6_UPD_PO_STATS_BH(net, idev,field,val)   \
 179		_DEVUPD(net, ipv6, 64_BH, idev, field, val)
 180#define ICMP6_INC_STATS(net, idev, field)	\
 181		_DEVINCATOMIC(net, icmpv6, , idev, field)
 182#define ICMP6_INC_STATS_BH(net, idev, field)	\
 183		_DEVINCATOMIC(net, icmpv6, _BH, idev, field)
 184
 185#define ICMP6MSGOUT_INC_STATS(net, idev, field)		\
 186	_DEVINC_ATOMIC_ATOMIC(net, icmpv6msg, idev, field +256)
 187#define ICMP6MSGOUT_INC_STATS_BH(net, idev, field)	\
 188	_DEVINC_ATOMIC_ATOMIC(net, icmpv6msg, idev, field +256)
 189#define ICMP6MSGIN_INC_STATS_BH(net, idev, field)	\
 190	_DEVINC_ATOMIC_ATOMIC(net, icmpv6msg, idev, field)
 191
 192struct ip6_ra_chain {
 193	struct ip6_ra_chain	*next;
 194	struct sock		*sk;
 195	int			sel;
 196	void			(*destructor)(struct sock *);
 197};
 198
 199extern struct ip6_ra_chain	*ip6_ra_chain;
 200extern rwlock_t ip6_ra_lock;
 201
 202/*
 203   This structure is prepared by protocol, when parsing
 204   ancillary data and passed to IPv6.
 205 */
 206
 207struct ipv6_txoptions {
 208	atomic_t		refcnt;
 209	/* Length of this structure */
 210	int			tot_len;
 211
 212	/* length of extension headers   */
 213
 214	__u16			opt_flen;	/* after fragment hdr */
 215	__u16			opt_nflen;	/* before fragment hdr */
 216
 217	struct ipv6_opt_hdr	*hopopt;
 218	struct ipv6_opt_hdr	*dst0opt;
 219	struct ipv6_rt_hdr	*srcrt;	/* Routing Header */
 220	struct ipv6_opt_hdr	*dst1opt;
 221	struct rcu_head		rcu;
 222	/* Option buffer, as read by IPV6_PKTOPTIONS, starts here. */
 223};
 224
 225struct ip6_flowlabel {
 226	struct ip6_flowlabel __rcu *next;
 227	__be32			label;
 228	atomic_t		users;
 229	struct in6_addr		dst;
 230	struct ipv6_txoptions	*opt;
 231	unsigned long		linger;
 232	struct rcu_head		rcu;
 233	u8			share;
 234	union {
 235		struct pid *pid;
 236		kuid_t uid;
 237	} owner;
 238	unsigned long		lastuse;
 239	unsigned long		expires;
 240	struct net		*fl_net;
 241};
 242
 243#define IPV6_FLOWINFO_MASK		cpu_to_be32(0x0FFFFFFF)
 244#define IPV6_FLOWLABEL_MASK		cpu_to_be32(0x000FFFFF)
 245#define IPV6_FLOWLABEL_STATELESS_FLAG	cpu_to_be32(0x00080000)
 246
 247#define IPV6_TCLASS_MASK (IPV6_FLOWINFO_MASK & ~IPV6_FLOWLABEL_MASK)
 248#define IPV6_TCLASS_SHIFT	20
 249
 250struct ipv6_fl_socklist {
 251	struct ipv6_fl_socklist	__rcu	*next;
 252	struct ip6_flowlabel		*fl;
 253	struct rcu_head			rcu;
 254};
 255
 256static inline struct ipv6_txoptions *txopt_get(const struct ipv6_pinfo *np)
 257{
 258	struct ipv6_txoptions *opt;
 259
 260	rcu_read_lock();
 261	opt = rcu_dereference(np->opt);
 262	if (opt) {
 263		if (!atomic_inc_not_zero(&opt->refcnt))
 264			opt = NULL;
 265		else
 266			opt = rcu_pointer_handoff(opt);
 267	}
 268	rcu_read_unlock();
 269	return opt;
 270}
 271
 272static inline void txopt_put(struct ipv6_txoptions *opt)
 273{
 274	if (opt && atomic_dec_and_test(&opt->refcnt))
 275		kfree_rcu(opt, rcu);
 276}
 277
 278struct ip6_flowlabel *fl6_sock_lookup(struct sock *sk, __be32 label);
 279struct ipv6_txoptions *fl6_merge_options(struct ipv6_txoptions *opt_space,
 280					 struct ip6_flowlabel *fl,
 281					 struct ipv6_txoptions *fopt);
 282void fl6_free_socklist(struct sock *sk);
 283int ipv6_flowlabel_opt(struct sock *sk, char __user *optval, int optlen);
 284int ipv6_flowlabel_opt_get(struct sock *sk, struct in6_flowlabel_req *freq,
 285			   int flags);
 286int ip6_flowlabel_init(void);
 287void ip6_flowlabel_cleanup(void);
 288
 289static inline void fl6_sock_release(struct ip6_flowlabel *fl)
 290{
 291	if (fl)
 292		atomic_dec(&fl->users);
 293}
 294
 295void icmpv6_notify(struct sk_buff *skb, u8 type, u8 code, __be32 info);
 296
 297int icmpv6_push_pending_frames(struct sock *sk, struct flowi6 *fl6,
 298			       struct icmp6hdr *thdr, int len);
 299
 300int ip6_ra_control(struct sock *sk, int sel);
 301
 302int ipv6_parse_hopopts(struct sk_buff *skb);
 303
 304struct ipv6_txoptions *ipv6_dup_options(struct sock *sk,
 305					struct ipv6_txoptions *opt);
 306struct ipv6_txoptions *ipv6_renew_options(struct sock *sk,
 307					  struct ipv6_txoptions *opt,
 308					  int newtype,
 309					  struct ipv6_opt_hdr __user *newopt,
 310					  int newoptlen);
 311struct ipv6_txoptions *ipv6_fixup_options(struct ipv6_txoptions *opt_space,
 312					  struct ipv6_txoptions *opt);
 313
 314bool ipv6_opt_accepted(const struct sock *sk, const struct sk_buff *skb,
 315		       const struct inet6_skb_parm *opt);
 316
 317static inline bool ipv6_accept_ra(struct inet6_dev *idev)
 318{
 319	/* If forwarding is enabled, RA are not accepted unless the special
 320	 * hybrid mode (accept_ra=2) is enabled.
 321	 */
 322	return idev->cnf.forwarding ? idev->cnf.accept_ra == 2 :
 323	    idev->cnf.accept_ra;
 324}
 325
 326#if IS_ENABLED(CONFIG_IPV6)
 327static inline int ip6_frag_mem(struct net *net)
 328{
 329	return sum_frag_mem_limit(&net->ipv6.frags);
 330}
 331#endif
 332
 333#define IPV6_FRAG_HIGH_THRESH	(4 * 1024*1024)	/* 4194304 */
 334#define IPV6_FRAG_LOW_THRESH	(3 * 1024*1024)	/* 3145728 */
 335#define IPV6_FRAG_TIMEOUT	(60 * HZ)	/* 60 seconds */
 336
 337int __ipv6_addr_type(const struct in6_addr *addr);
 338static inline int ipv6_addr_type(const struct in6_addr *addr)
 339{
 340	return __ipv6_addr_type(addr) & 0xffff;
 341}
 342
 343static inline int ipv6_addr_scope(const struct in6_addr *addr)
 344{
 345	return __ipv6_addr_type(addr) & IPV6_ADDR_SCOPE_MASK;
 346}
 347
 348static inline int __ipv6_addr_src_scope(int type)
 349{
 350	return (type == IPV6_ADDR_ANY) ? __IPV6_ADDR_SCOPE_INVALID : (type >> 16);
 351}
 352
 353static inline int ipv6_addr_src_scope(const struct in6_addr *addr)
 354{
 355	return __ipv6_addr_src_scope(__ipv6_addr_type(addr));
 356}
 357
 358static inline bool __ipv6_addr_needs_scope_id(int type)
 359{
 360	return type & IPV6_ADDR_LINKLOCAL ||
 361	       (type & IPV6_ADDR_MULTICAST &&
 362		(type & (IPV6_ADDR_LOOPBACK|IPV6_ADDR_LINKLOCAL)));
 363}
 364
 365static inline __u32 ipv6_iface_scope_id(const struct in6_addr *addr, int iface)
 366{
 367	return __ipv6_addr_needs_scope_id(__ipv6_addr_type(addr)) ? iface : 0;
 368}
 369
 370static inline int ipv6_addr_cmp(const struct in6_addr *a1, const struct in6_addr *a2)
 371{
 372	return memcmp(a1, a2, sizeof(struct in6_addr));
 373}
 374
 375static inline bool
 376ipv6_masked_addr_cmp(const struct in6_addr *a1, const struct in6_addr *m,
 377		     const struct in6_addr *a2)
 378{
 379#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 380	const unsigned long *ul1 = (const unsigned long *)a1;
 381	const unsigned long *ulm = (const unsigned long *)m;
 382	const unsigned long *ul2 = (const unsigned long *)a2;
 383
 384	return !!(((ul1[0] ^ ul2[0]) & ulm[0]) |
 385		  ((ul1[1] ^ ul2[1]) & ulm[1]));
 386#else
 387	return !!(((a1->s6_addr32[0] ^ a2->s6_addr32[0]) & m->s6_addr32[0]) |
 388		  ((a1->s6_addr32[1] ^ a2->s6_addr32[1]) & m->s6_addr32[1]) |
 389		  ((a1->s6_addr32[2] ^ a2->s6_addr32[2]) & m->s6_addr32[2]) |
 390		  ((a1->s6_addr32[3] ^ a2->s6_addr32[3]) & m->s6_addr32[3]));
 391#endif
 392}
 393
 394static inline void ipv6_addr_prefix(struct in6_addr *pfx, 
 395				    const struct in6_addr *addr,
 396				    int plen)
 397{
 398	/* caller must guarantee 0 <= plen <= 128 */
 399	int o = plen >> 3,
 400	    b = plen & 0x7;
 401
 402	memset(pfx->s6_addr, 0, sizeof(pfx->s6_addr));
 403	memcpy(pfx->s6_addr, addr, o);
 404	if (b != 0)
 405		pfx->s6_addr[o] = addr->s6_addr[o] & (0xff00 >> b);
 406}
 407
 408static inline void ipv6_addr_prefix_copy(struct in6_addr *addr,
 409					 const struct in6_addr *pfx,
 410					 int plen)
 411{
 412	/* caller must guarantee 0 <= plen <= 128 */
 413	int o = plen >> 3,
 414	    b = plen & 0x7;
 415
 416	memcpy(addr->s6_addr, pfx, o);
 417	if (b != 0) {
 418		addr->s6_addr[o] &= ~(0xff00 >> b);
 419		addr->s6_addr[o] |= (pfx->s6_addr[o] & (0xff00 >> b));
 420	}
 421}
 422
 423static inline void __ipv6_addr_set_half(__be32 *addr,
 424					__be32 wh, __be32 wl)
 425{
 426#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 427#if defined(__BIG_ENDIAN)
 428	if (__builtin_constant_p(wh) && __builtin_constant_p(wl)) {
 429		*(__force u64 *)addr = ((__force u64)(wh) << 32 | (__force u64)(wl));
 430		return;
 431	}
 432#elif defined(__LITTLE_ENDIAN)
 433	if (__builtin_constant_p(wl) && __builtin_constant_p(wh)) {
 434		*(__force u64 *)addr = ((__force u64)(wl) << 32 | (__force u64)(wh));
 435		return;
 436	}
 437#endif
 438#endif
 439	addr[0] = wh;
 440	addr[1] = wl;
 441}
 442
 443static inline void ipv6_addr_set(struct in6_addr *addr, 
 444				     __be32 w1, __be32 w2,
 445				     __be32 w3, __be32 w4)
 446{
 447	__ipv6_addr_set_half(&addr->s6_addr32[0], w1, w2);
 448	__ipv6_addr_set_half(&addr->s6_addr32[2], w3, w4);
 449}
 450
 451static inline bool ipv6_addr_equal(const struct in6_addr *a1,
 452				   const struct in6_addr *a2)
 453{
 454#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 455	const unsigned long *ul1 = (const unsigned long *)a1;
 456	const unsigned long *ul2 = (const unsigned long *)a2;
 457
 458	return ((ul1[0] ^ ul2[0]) | (ul1[1] ^ ul2[1])) == 0UL;
 459#else
 460	return ((a1->s6_addr32[0] ^ a2->s6_addr32[0]) |
 461		(a1->s6_addr32[1] ^ a2->s6_addr32[1]) |
 462		(a1->s6_addr32[2] ^ a2->s6_addr32[2]) |
 463		(a1->s6_addr32[3] ^ a2->s6_addr32[3])) == 0;
 464#endif
 465}
 466
 467#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 468static inline bool __ipv6_prefix_equal64_half(const __be64 *a1,
 469					      const __be64 *a2,
 470					      unsigned int len)
 471{
 472	if (len && ((*a1 ^ *a2) & cpu_to_be64((~0UL) << (64 - len))))
 473		return false;
 474	return true;
 475}
 476
 477static inline bool ipv6_prefix_equal(const struct in6_addr *addr1,
 478				     const struct in6_addr *addr2,
 479				     unsigned int prefixlen)
 480{
 481	const __be64 *a1 = (const __be64 *)addr1;
 482	const __be64 *a2 = (const __be64 *)addr2;
 483
 484	if (prefixlen >= 64) {
 485		if (a1[0] ^ a2[0])
 486			return false;
 487		return __ipv6_prefix_equal64_half(a1 + 1, a2 + 1, prefixlen - 64);
 488	}
 489	return __ipv6_prefix_equal64_half(a1, a2, prefixlen);
 490}
 491#else
 492static inline bool ipv6_prefix_equal(const struct in6_addr *addr1,
 493				     const struct in6_addr *addr2,
 494				     unsigned int prefixlen)
 495{
 496	const __be32 *a1 = addr1->s6_addr32;
 497	const __be32 *a2 = addr2->s6_addr32;
 498	unsigned int pdw, pbi;
 499
 500	/* check complete u32 in prefix */
 501	pdw = prefixlen >> 5;
 502	if (pdw && memcmp(a1, a2, pdw << 2))
 503		return false;
 504
 505	/* check incomplete u32 in prefix */
 506	pbi = prefixlen & 0x1f;
 507	if (pbi && ((a1[pdw] ^ a2[pdw]) & htonl((0xffffffff) << (32 - pbi))))
 508		return false;
 509
 510	return true;
 511}
 512#endif
 513
 514struct inet_frag_queue;
 515
 516enum ip6_defrag_users {
 517	IP6_DEFRAG_LOCAL_DELIVER,
 518	IP6_DEFRAG_CONNTRACK_IN,
 519	__IP6_DEFRAG_CONNTRACK_IN	= IP6_DEFRAG_CONNTRACK_IN + USHRT_MAX,
 520	IP6_DEFRAG_CONNTRACK_OUT,
 521	__IP6_DEFRAG_CONNTRACK_OUT	= IP6_DEFRAG_CONNTRACK_OUT + USHRT_MAX,
 522	IP6_DEFRAG_CONNTRACK_BRIDGE_IN,
 523	__IP6_DEFRAG_CONNTRACK_BRIDGE_IN = IP6_DEFRAG_CONNTRACK_BRIDGE_IN + USHRT_MAX,
 524};
 525
 526struct ip6_create_arg {
 527	__be32 id;
 528	u32 user;
 529	const struct in6_addr *src;
 530	const struct in6_addr *dst;
 531	int iif;
 532	u8 ecn;
 533};
 534
 535void ip6_frag_init(struct inet_frag_queue *q, const void *a);
 536bool ip6_frag_match(const struct inet_frag_queue *q, const void *a);
 537
 538/*
 539 *	Equivalent of ipv4 struct ip
 540 */
 541struct frag_queue {
 542	struct inet_frag_queue	q;
 543
 544	__be32			id;		/* fragment id		*/
 545	u32			user;
 546	struct in6_addr		saddr;
 547	struct in6_addr		daddr;
 548
 549	int			iif;
 550	unsigned int		csum;
 551	__u16			nhoffset;
 552	u8			ecn;
 553};
 554
 555void ip6_expire_frag_queue(struct net *net, struct frag_queue *fq,
 556			   struct inet_frags *frags);
 557
 558static inline bool ipv6_addr_any(const struct in6_addr *a)
 559{
 560#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 561	const unsigned long *ul = (const unsigned long *)a;
 562
 563	return (ul[0] | ul[1]) == 0UL;
 564#else
 565	return (a->s6_addr32[0] | a->s6_addr32[1] |
 566		a->s6_addr32[2] | a->s6_addr32[3]) == 0;
 567#endif
 568}
 569
 570static inline u32 ipv6_addr_hash(const struct in6_addr *a)
 571{
 572#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 573	const unsigned long *ul = (const unsigned long *)a;
 574	unsigned long x = ul[0] ^ ul[1];
 575
 576	return (u32)(x ^ (x >> 32));
 577#else
 578	return (__force u32)(a->s6_addr32[0] ^ a->s6_addr32[1] ^
 579			     a->s6_addr32[2] ^ a->s6_addr32[3]);
 580#endif
 581}
 582
 583/* more secured version of ipv6_addr_hash() */
 584static inline u32 __ipv6_addr_jhash(const struct in6_addr *a, const u32 initval)
 585{
 586	u32 v = (__force u32)a->s6_addr32[0] ^ (__force u32)a->s6_addr32[1];
 587
 588	return jhash_3words(v,
 589			    (__force u32)a->s6_addr32[2],
 590			    (__force u32)a->s6_addr32[3],
 591			    initval);
 592}
 593
 594static inline bool ipv6_addr_loopback(const struct in6_addr *a)
 595{
 596#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 597	const __be64 *be = (const __be64 *)a;
 598
 599	return (be[0] | (be[1] ^ cpu_to_be64(1))) == 0UL;
 600#else
 601	return (a->s6_addr32[0] | a->s6_addr32[1] |
 602		a->s6_addr32[2] | (a->s6_addr32[3] ^ cpu_to_be32(1))) == 0;
 603#endif
 604}
 605
 606/*
 607 * Note that we must __force cast these to unsigned long to make sparse happy,
 608 * since all of the endian-annotated types are fixed size regardless of arch.
 609 */
 610static inline bool ipv6_addr_v4mapped(const struct in6_addr *a)
 611{
 612	return (
 613#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 614		*(unsigned long *)a |
 615#else
 616		(__force unsigned long)(a->s6_addr32[0] | a->s6_addr32[1]) |
 617#endif
 618		(__force unsigned long)(a->s6_addr32[2] ^
 619					cpu_to_be32(0x0000ffff))) == 0UL;
 620}
 621
 622/*
 623 * Check for a RFC 4843 ORCHID address
 624 * (Overlay Routable Cryptographic Hash Identifiers)
 625 */
 626static inline bool ipv6_addr_orchid(const struct in6_addr *a)
 627{
 628	return (a->s6_addr32[0] & htonl(0xfffffff0)) == htonl(0x20010010);
 629}
 630
 631static inline bool ipv6_addr_is_multicast(const struct in6_addr *addr)
 632{
 633	return (addr->s6_addr32[0] & htonl(0xFF000000)) == htonl(0xFF000000);
 634}
 635
 636static inline void ipv6_addr_set_v4mapped(const __be32 addr,
 637					  struct in6_addr *v4mapped)
 638{
 639	ipv6_addr_set(v4mapped,
 640			0, 0,
 641			htonl(0x0000FFFF),
 642			addr);
 643}
 644
 645/*
 646 * find the first different bit between two addresses
 647 * length of address must be a multiple of 32bits
 648 */
 649static inline int __ipv6_addr_diff32(const void *token1, const void *token2, int addrlen)
 650{
 651	const __be32 *a1 = token1, *a2 = token2;
 652	int i;
 653
 654	addrlen >>= 2;
 655
 656	for (i = 0; i < addrlen; i++) {
 657		__be32 xb = a1[i] ^ a2[i];
 658		if (xb)
 659			return i * 32 + 31 - __fls(ntohl(xb));
 660	}
 661
 662	/*
 663	 *	we should *never* get to this point since that 
 664	 *	would mean the addrs are equal
 665	 *
 666	 *	However, we do get to it 8) And exacly, when
 667	 *	addresses are equal 8)
 668	 *
 669	 *	ip route add 1111::/128 via ...
 670	 *	ip route add 1111::/64 via ...
 671	 *	and we are here.
 672	 *
 673	 *	Ideally, this function should stop comparison
 674	 *	at prefix length. It does not, but it is still OK,
 675	 *	if returned value is greater than prefix length.
 676	 *					--ANK (980803)
 677	 */
 678	return addrlen << 5;
 679}
 680
 681#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 682static inline int __ipv6_addr_diff64(const void *token1, const void *token2, int addrlen)
 683{
 684	const __be64 *a1 = token1, *a2 = token2;
 685	int i;
 686
 687	addrlen >>= 3;
 688
 689	for (i = 0; i < addrlen; i++) {
 690		__be64 xb = a1[i] ^ a2[i];
 691		if (xb)
 692			return i * 64 + 63 - __fls(be64_to_cpu(xb));
 693	}
 694
 695	return addrlen << 6;
 696}
 697#endif
 698
 699static inline int __ipv6_addr_diff(const void *token1, const void *token2, int addrlen)
 700{
 701#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 702	if (__builtin_constant_p(addrlen) && !(addrlen & 7))
 703		return __ipv6_addr_diff64(token1, token2, addrlen);
 704#endif
 705	return __ipv6_addr_diff32(token1, token2, addrlen);
 706}
 707
 708static inline int ipv6_addr_diff(const struct in6_addr *a1, const struct in6_addr *a2)
 709{
 710	return __ipv6_addr_diff(a1, a2, sizeof(struct in6_addr));
 711}
 712
 713__be32 ipv6_select_ident(struct net *net,
 714			 const struct in6_addr *daddr,
 715			 const struct in6_addr *saddr);
 716void ipv6_proxy_select_ident(struct net *net, struct sk_buff *skb);
 717
 718int ip6_dst_hoplimit(struct dst_entry *dst);
 719
 720static inline int ip6_sk_dst_hoplimit(struct ipv6_pinfo *np, struct flowi6 *fl6,
 721				      struct dst_entry *dst)
 722{
 723	int hlimit;
 724
 725	if (ipv6_addr_is_multicast(&fl6->daddr))
 726		hlimit = np->mcast_hops;
 727	else
 728		hlimit = np->hop_limit;
 729	if (hlimit < 0)
 730		hlimit = ip6_dst_hoplimit(dst);
 731	return hlimit;
 732}
 733
 734/* copy IPv6 saddr & daddr to flow_keys, possibly using 64bit load/store
 735 * Equivalent to :	flow->v6addrs.src = iph->saddr;
 736 *			flow->v6addrs.dst = iph->daddr;
 737 */
 738static inline void iph_to_flow_copy_v6addrs(struct flow_keys *flow,
 739					    const struct ipv6hdr *iph)
 740{
 741	BUILD_BUG_ON(offsetof(typeof(flow->addrs), v6addrs.dst) !=
 742		     offsetof(typeof(flow->addrs), v6addrs.src) +
 743		     sizeof(flow->addrs.v6addrs.src));
 744	memcpy(&flow->addrs.v6addrs, &iph->saddr, sizeof(flow->addrs.v6addrs));
 745	flow->control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
 746}
 747
 748#if IS_ENABLED(CONFIG_IPV6)
 749
 750/* Sysctl settings for net ipv6.auto_flowlabels */
 751#define IP6_AUTO_FLOW_LABEL_OFF		0
 752#define IP6_AUTO_FLOW_LABEL_OPTOUT	1
 753#define IP6_AUTO_FLOW_LABEL_OPTIN	2
 754#define IP6_AUTO_FLOW_LABEL_FORCED	3
 755
 756#define IP6_AUTO_FLOW_LABEL_MAX		IP6_AUTO_FLOW_LABEL_FORCED
 757
 758#define IP6_DEFAULT_AUTO_FLOW_LABELS	IP6_AUTO_FLOW_LABEL_OPTOUT
 759
 760static inline __be32 ip6_make_flowlabel(struct net *net, struct sk_buff *skb,
 761					__be32 flowlabel, bool autolabel,
 762					struct flowi6 *fl6)
 763{
 764	u32 hash;
 765
 766	if (flowlabel ||
 767	    net->ipv6.sysctl.auto_flowlabels == IP6_AUTO_FLOW_LABEL_OFF ||
 768	    (!autolabel &&
 769	     net->ipv6.sysctl.auto_flowlabels != IP6_AUTO_FLOW_LABEL_FORCED))
 770		return flowlabel;
 771
 772	hash = skb_get_hash_flowi6(skb, fl6);
 773
 774	/* Since this is being sent on the wire obfuscate hash a bit
 775	 * to minimize possbility that any useful information to an
 776	 * attacker is leaked. Only lower 20 bits are relevant.
 777	 */
 778	rol32(hash, 16);
 779
 780	flowlabel = (__force __be32)hash & IPV6_FLOWLABEL_MASK;
 781
 782	if (net->ipv6.sysctl.flowlabel_state_ranges)
 783		flowlabel |= IPV6_FLOWLABEL_STATELESS_FLAG;
 784
 785	return flowlabel;
 786}
 787
 788static inline int ip6_default_np_autolabel(struct net *net)
 789{
 790	switch (net->ipv6.sysctl.auto_flowlabels) {
 791	case IP6_AUTO_FLOW_LABEL_OFF:
 792	case IP6_AUTO_FLOW_LABEL_OPTIN:
 793	default:
 794		return 0;
 795	case IP6_AUTO_FLOW_LABEL_OPTOUT:
 796	case IP6_AUTO_FLOW_LABEL_FORCED:
 797		return 1;
 798	}
 799}
 800#else
 801static inline void ip6_set_txhash(struct sock *sk) { }
 802static inline __be32 ip6_make_flowlabel(struct net *net, struct sk_buff *skb,
 803					__be32 flowlabel, bool autolabel,
 804					struct flowi6 *fl6)
 805{
 806	return flowlabel;
 807}
 808static inline int ip6_default_np_autolabel(struct net *net)
 809{
 810	return 0;
 811}
 812#endif
 813
 814
 815/*
 816 *	Header manipulation
 817 */
 818static inline void ip6_flow_hdr(struct ipv6hdr *hdr, unsigned int tclass,
 819				__be32 flowlabel)
 820{
 821	*(__be32 *)hdr = htonl(0x60000000 | (tclass << 20)) | flowlabel;
 822}
 823
 824static inline __be32 ip6_flowinfo(const struct ipv6hdr *hdr)
 825{
 826	return *(__be32 *)hdr & IPV6_FLOWINFO_MASK;
 827}
 828
 829static inline __be32 ip6_flowlabel(const struct ipv6hdr *hdr)
 830{
 831	return *(__be32 *)hdr & IPV6_FLOWLABEL_MASK;
 832}
 833
 834static inline u8 ip6_tclass(__be32 flowinfo)
 835{
 836	return ntohl(flowinfo & IPV6_TCLASS_MASK) >> IPV6_TCLASS_SHIFT;
 837}
 838
 839static inline __be32 ip6_make_flowinfo(unsigned int tclass, __be32 flowlabel)
 840{
 841	return htonl(tclass << IPV6_TCLASS_SHIFT) | flowlabel;
 842}
 843
 844/*
 845 *	Prototypes exported by ipv6
 846 */
 847
 848/*
 849 *	rcv function (called from netdevice level)
 850 */
 851
 852int ipv6_rcv(struct sk_buff *skb, struct net_device *dev,
 853	     struct packet_type *pt, struct net_device *orig_dev);
 854
 855int ip6_rcv_finish(struct net *net, struct sock *sk, struct sk_buff *skb);
 856
 857/*
 858 *	upper-layer output functions
 859 */
 860int ip6_xmit(const struct sock *sk, struct sk_buff *skb, struct flowi6 *fl6,
 861	     struct ipv6_txoptions *opt, int tclass);
 862
 863int ip6_find_1stfragopt(struct sk_buff *skb, u8 **nexthdr);
 864
 865int ip6_append_data(struct sock *sk,
 866		    int getfrag(void *from, char *to, int offset, int len,
 867				int odd, struct sk_buff *skb),
 868		    void *from, int length, int transhdrlen, int hlimit,
 869		    int tclass, struct ipv6_txoptions *opt, struct flowi6 *fl6,
 870		    struct rt6_info *rt, unsigned int flags, int dontfrag);
 871
 872int ip6_push_pending_frames(struct sock *sk);
 873
 874void ip6_flush_pending_frames(struct sock *sk);
 875
 876int ip6_send_skb(struct sk_buff *skb);
 877
 878struct sk_buff *__ip6_make_skb(struct sock *sk, struct sk_buff_head *queue,
 879			       struct inet_cork_full *cork,
 880			       struct inet6_cork *v6_cork);
 881struct sk_buff *ip6_make_skb(struct sock *sk,
 882			     int getfrag(void *from, char *to, int offset,
 883					 int len, int odd, struct sk_buff *skb),
 884			     void *from, int length, int transhdrlen,
 885			     int hlimit, int tclass, struct ipv6_txoptions *opt,
 886			     struct flowi6 *fl6, struct rt6_info *rt,
 887			     unsigned int flags, int dontfrag);
 888
 889static inline struct sk_buff *ip6_finish_skb(struct sock *sk)
 890{
 891	return __ip6_make_skb(sk, &sk->sk_write_queue, &inet_sk(sk)->cork,
 892			      &inet6_sk(sk)->cork);
 893}
 894
 895int ip6_dst_lookup(struct net *net, struct sock *sk, struct dst_entry **dst,
 896		   struct flowi6 *fl6);
 897struct dst_entry *ip6_dst_lookup_flow(const struct sock *sk, struct flowi6 *fl6,
 898				      const struct in6_addr *final_dst);
 899struct dst_entry *ip6_sk_dst_lookup_flow(struct sock *sk, struct flowi6 *fl6,
 900					 const struct in6_addr *final_dst);
 901struct dst_entry *ip6_blackhole_route(struct net *net,
 902				      struct dst_entry *orig_dst);
 903
 904/*
 905 *	skb processing functions
 906 */
 907
 908int ip6_output(struct net *net, struct sock *sk, struct sk_buff *skb);
 909int ip6_forward(struct sk_buff *skb);
 910int ip6_input(struct sk_buff *skb);
 911int ip6_mc_input(struct sk_buff *skb);
 912
 913int __ip6_local_out(struct net *net, struct sock *sk, struct sk_buff *skb);
 914int ip6_local_out(struct net *net, struct sock *sk, struct sk_buff *skb);
 915
 916/*
 917 *	Extension header (options) processing
 918 */
 919
 920void ipv6_push_nfrag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt,
 921			  u8 *proto, struct in6_addr **daddr_p);
 922void ipv6_push_frag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt,
 923			 u8 *proto);
 924
 925int ipv6_skip_exthdr(const struct sk_buff *, int start, u8 *nexthdrp,
 926		     __be16 *frag_offp);
 927
 928bool ipv6_ext_hdr(u8 nexthdr);
 929
 930enum {
 931	IP6_FH_F_FRAG		= (1 << 0),
 932	IP6_FH_F_AUTH		= (1 << 1),
 933	IP6_FH_F_SKIP_RH	= (1 << 2),
 934};
 935
 936/* find specified header and get offset to it */
 937int ipv6_find_hdr(const struct sk_buff *skb, unsigned int *offset, int target,
 938		  unsigned short *fragoff, int *fragflg);
 939
 940int ipv6_find_tlv(struct sk_buff *skb, int offset, int type);
 941
 942struct in6_addr *fl6_update_dst(struct flowi6 *fl6,
 943				const struct ipv6_txoptions *opt,
 944				struct in6_addr *orig);
 945
 946/*
 947 *	socket options (ipv6_sockglue.c)
 948 */
 949
 950int ipv6_setsockopt(struct sock *sk, int level, int optname,
 951		    char __user *optval, unsigned int optlen);
 952int ipv6_getsockopt(struct sock *sk, int level, int optname,
 953		    char __user *optval, int __user *optlen);
 954int compat_ipv6_setsockopt(struct sock *sk, int level, int optname,
 955			   char __user *optval, unsigned int optlen);
 956int compat_ipv6_getsockopt(struct sock *sk, int level, int optname,
 957			   char __user *optval, int __user *optlen);
 958
 959int ip6_datagram_connect(struct sock *sk, struct sockaddr *addr, int addr_len);
 960int ip6_datagram_connect_v6_only(struct sock *sk, struct sockaddr *addr,
 961				 int addr_len);
 962int ip6_datagram_dst_update(struct sock *sk, bool fix_sk_saddr);
 963void ip6_datagram_release_cb(struct sock *sk);
 964
 965int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len,
 966		    int *addr_len);
 967int ipv6_recv_rxpmtu(struct sock *sk, struct msghdr *msg, int len,
 968		     int *addr_len);
 969void ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err, __be16 port,
 970		     u32 info, u8 *payload);
 971void ipv6_local_error(struct sock *sk, int err, struct flowi6 *fl6, u32 info);
 972void ipv6_local_rxpmtu(struct sock *sk, struct flowi6 *fl6, u32 mtu);
 973
 974int inet6_release(struct socket *sock);
 975int inet6_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len);
 976int inet6_getname(struct socket *sock, struct sockaddr *uaddr, int *uaddr_len,
 977		  int peer);
 978int inet6_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg);
 979
 980int inet6_hash_connect(struct inet_timewait_death_row *death_row,
 981			      struct sock *sk);
 982
 983/*
 984 * reassembly.c
 985 */
 986extern const struct proto_ops inet6_stream_ops;
 987extern const struct proto_ops inet6_dgram_ops;
 988
 989struct group_source_req;
 990struct group_filter;
 991
 992int ip6_mc_source(int add, int omode, struct sock *sk,
 993		  struct group_source_req *pgsr);
 994int ip6_mc_msfilter(struct sock *sk, struct group_filter *gsf);
 995int ip6_mc_msfget(struct sock *sk, struct group_filter *gsf,
 996		  struct group_filter __user *optval, int __user *optlen);
 997
 998#ifdef CONFIG_PROC_FS
 999int ac6_proc_init(struct net *net);
1000void ac6_proc_exit(struct net *net);
1001int raw6_proc_init(void);
1002void raw6_proc_exit(void);
1003int tcp6_proc_init(struct net *net);
1004void tcp6_proc_exit(struct net *net);
1005int udp6_proc_init(struct net *net);
1006void udp6_proc_exit(struct net *net);
1007int udplite6_proc_init(void);
1008void udplite6_proc_exit(void);
1009int ipv6_misc_proc_init(void);
1010void ipv6_misc_proc_exit(void);
1011int snmp6_register_dev(struct inet6_dev *idev);
1012int snmp6_unregister_dev(struct inet6_dev *idev);
1013
1014#else
1015static inline int ac6_proc_init(struct net *net) { return 0; }
1016static inline void ac6_proc_exit(struct net *net) { }
1017static inline int snmp6_register_dev(struct inet6_dev *idev) { return 0; }
1018static inline int snmp6_unregister_dev(struct inet6_dev *idev) { return 0; }
1019#endif
1020
1021#ifdef CONFIG_SYSCTL
1022extern struct ctl_table ipv6_route_table_template[];
1023
1024struct ctl_table *ipv6_icmp_sysctl_init(struct net *net);
1025struct ctl_table *ipv6_route_sysctl_init(struct net *net);
1026int ipv6_sysctl_register(void);
1027void ipv6_sysctl_unregister(void);
1028#endif
1029
1030int ipv6_sock_mc_join(struct sock *sk, int ifindex,
1031		      const struct in6_addr *addr);
1032int ipv6_sock_mc_drop(struct sock *sk, int ifindex,
1033		      const struct in6_addr *addr);
1034#endif /* _NET_IPV6_H */
   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/ndisc.h>
  19#include <net/flow.h>
  20#include <net/flow_dissector.h>
  21#include <net/snmp.h>
  22#include <net/netns/hash.h>
  23
  24#define SIN6_LEN_RFC2133	24
  25
  26#define IPV6_MAXPLEN		65535
  27
  28/*
  29 *	NextHeader field of IPv6 header
  30 */
  31
  32#define NEXTHDR_HOP		0	/* Hop-by-hop option header. */
  33#define NEXTHDR_TCP		6	/* TCP segment. */
  34#define NEXTHDR_UDP		17	/* UDP message. */
  35#define NEXTHDR_IPV6		41	/* IPv6 in IPv6 */
  36#define NEXTHDR_ROUTING		43	/* Routing header. */
  37#define NEXTHDR_FRAGMENT	44	/* Fragmentation/reassembly header. */
  38#define NEXTHDR_GRE		47	/* GRE header. */
  39#define NEXTHDR_ESP		50	/* Encapsulating security payload. */
  40#define NEXTHDR_AUTH		51	/* Authentication header. */
  41#define NEXTHDR_ICMP		58	/* ICMP for IPv6. */
  42#define NEXTHDR_NONE		59	/* No next header */
  43#define NEXTHDR_DEST		60	/* Destination options header. */
  44#define NEXTHDR_SCTP		132	/* SCTP message. */
  45#define NEXTHDR_MOBILITY	135	/* Mobility header. */
  46
  47#define NEXTHDR_MAX		255
  48
  49#define IPV6_DEFAULT_HOPLIMIT   64
  50#define IPV6_DEFAULT_MCASTHOPS	1
  51
  52/* Limits on Hop-by-Hop and Destination options.
  53 *
  54 * Per RFC8200 there is no limit on the maximum number or lengths of options in
  55 * Hop-by-Hop or Destination options other then the packet must fit in an MTU.
  56 * We allow configurable limits in order to mitigate potential denial of
  57 * service attacks.
  58 *
  59 * There are three limits that may be set:
  60 *   - Limit the number of options in a Hop-by-Hop or Destination options
  61 *     extension header
  62 *   - Limit the byte length of a Hop-by-Hop or Destination options extension
  63 *     header
  64 *   - Disallow unknown options
  65 *
  66 * The limits are expressed in corresponding sysctls:
  67 *
  68 * ipv6.sysctl.max_dst_opts_cnt
  69 * ipv6.sysctl.max_hbh_opts_cnt
  70 * ipv6.sysctl.max_dst_opts_len
  71 * ipv6.sysctl.max_hbh_opts_len
  72 *
  73 * max_*_opts_cnt is the number of TLVs that are allowed for Destination
  74 * options or Hop-by-Hop options. If the number is less than zero then unknown
  75 * TLVs are disallowed and the number of known options that are allowed is the
  76 * absolute value. Setting the value to INT_MAX indicates no limit.
  77 *
  78 * max_*_opts_len is the length limit in bytes of a Destination or
  79 * Hop-by-Hop options extension header. Setting the value to INT_MAX
  80 * indicates no length limit.
  81 *
  82 * If a limit is exceeded when processing an extension header the packet is
  83 * silently discarded.
  84 */
  85
  86/* Default limits for Hop-by-Hop and Destination options */
  87#define IP6_DEFAULT_MAX_DST_OPTS_CNT	 8
  88#define IP6_DEFAULT_MAX_HBH_OPTS_CNT	 8
  89#define IP6_DEFAULT_MAX_DST_OPTS_LEN	 INT_MAX /* No limit */
  90#define IP6_DEFAULT_MAX_HBH_OPTS_LEN	 INT_MAX /* No limit */
  91
  92/*
  93 *	Addr type
  94 *	
  95 *	type	-	unicast | multicast
  96 *	scope	-	local	| site	    | global
  97 *	v4	-	compat
  98 *	v4mapped
  99 *	any
 100 *	loopback
 101 */
 102
 103#define IPV6_ADDR_ANY		0x0000U
 104
 105#define IPV6_ADDR_UNICAST	0x0001U
 106#define IPV6_ADDR_MULTICAST	0x0002U
 107
 108#define IPV6_ADDR_LOOPBACK	0x0010U
 109#define IPV6_ADDR_LINKLOCAL	0x0020U
 110#define IPV6_ADDR_SITELOCAL	0x0040U
 111
 112#define IPV6_ADDR_COMPATv4	0x0080U
 113
 114#define IPV6_ADDR_SCOPE_MASK	0x00f0U
 115
 116#define IPV6_ADDR_MAPPED	0x1000U
 117
 118/*
 119 *	Addr scopes
 120 */
 121#define IPV6_ADDR_MC_SCOPE(a)	\
 122	((a)->s6_addr[1] & 0x0f)	/* nonstandard */
 123#define __IPV6_ADDR_SCOPE_INVALID	-1
 124#define IPV6_ADDR_SCOPE_NODELOCAL	0x01
 125#define IPV6_ADDR_SCOPE_LINKLOCAL	0x02
 126#define IPV6_ADDR_SCOPE_SITELOCAL	0x05
 127#define IPV6_ADDR_SCOPE_ORGLOCAL	0x08
 128#define IPV6_ADDR_SCOPE_GLOBAL		0x0e
 129
 130/*
 131 *	Addr flags
 132 */
 133#define IPV6_ADDR_MC_FLAG_TRANSIENT(a)	\
 134	((a)->s6_addr[1] & 0x10)
 135#define IPV6_ADDR_MC_FLAG_PREFIX(a)	\
 136	((a)->s6_addr[1] & 0x20)
 137#define IPV6_ADDR_MC_FLAG_RENDEZVOUS(a)	\
 138	((a)->s6_addr[1] & 0x40)
 139
 140/*
 141 *	fragmentation header
 142 */
 143
 144struct frag_hdr {
 145	__u8	nexthdr;
 146	__u8	reserved;
 147	__be16	frag_off;
 148	__be32	identification;
 149};
 150
 151#define	IP6_MF		0x0001
 152#define	IP6_OFFSET	0xFFF8
 153
 154struct ip6_fraglist_iter {
 155	struct ipv6hdr	*tmp_hdr;
 156	struct sk_buff	*frag;
 157	int		offset;
 158	unsigned int	hlen;
 159	__be32		frag_id;
 160	u8		nexthdr;
 161};
 162
 163int ip6_fraglist_init(struct sk_buff *skb, unsigned int hlen, u8 *prevhdr,
 164		      u8 nexthdr, __be32 frag_id,
 165		      struct ip6_fraglist_iter *iter);
 166void ip6_fraglist_prepare(struct sk_buff *skb, struct ip6_fraglist_iter *iter);
 167
 168static inline struct sk_buff *ip6_fraglist_next(struct ip6_fraglist_iter *iter)
 169{
 170	struct sk_buff *skb = iter->frag;
 171
 172	iter->frag = skb->next;
 173	skb_mark_not_on_list(skb);
 174
 175	return skb;
 176}
 177
 178struct ip6_frag_state {
 179	u8		*prevhdr;
 180	unsigned int	hlen;
 181	unsigned int	mtu;
 182	unsigned int	left;
 183	int		offset;
 184	int		ptr;
 185	int		hroom;
 186	int		troom;
 187	__be32		frag_id;
 188	u8		nexthdr;
 189};
 190
 191void ip6_frag_init(struct sk_buff *skb, unsigned int hlen, unsigned int mtu,
 192		   unsigned short needed_tailroom, int hdr_room, u8 *prevhdr,
 193		   u8 nexthdr, __be32 frag_id, struct ip6_frag_state *state);
 194struct sk_buff *ip6_frag_next(struct sk_buff *skb,
 195			      struct ip6_frag_state *state);
 196
 197#define IP6_REPLY_MARK(net, mark) \
 198	((net)->ipv6.sysctl.fwmark_reflect ? (mark) : 0)
 199
 200#include <net/sock.h>
 201
 202/* sysctls */
 203extern int sysctl_mld_max_msf;
 204extern int sysctl_mld_qrv;
 205
 206#define _DEVINC(net, statname, mod, idev, field)			\
 207({									\
 208	struct inet6_dev *_idev = (idev);				\
 209	if (likely(_idev != NULL))					\
 210		mod##SNMP_INC_STATS64((_idev)->stats.statname, (field));\
 211	mod##SNMP_INC_STATS64((net)->mib.statname##_statistics, (field));\
 212})
 213
 214/* per device counters are atomic_long_t */
 215#define _DEVINCATOMIC(net, statname, mod, idev, field)			\
 216({									\
 217	struct inet6_dev *_idev = (idev);				\
 218	if (likely(_idev != NULL))					\
 219		SNMP_INC_STATS_ATOMIC_LONG((_idev)->stats.statname##dev, (field)); \
 220	mod##SNMP_INC_STATS((net)->mib.statname##_statistics, (field));\
 221})
 222
 223/* per device and per net counters are atomic_long_t */
 224#define _DEVINC_ATOMIC_ATOMIC(net, statname, idev, field)		\
 225({									\
 226	struct inet6_dev *_idev = (idev);				\
 227	if (likely(_idev != NULL))					\
 228		SNMP_INC_STATS_ATOMIC_LONG((_idev)->stats.statname##dev, (field)); \
 229	SNMP_INC_STATS_ATOMIC_LONG((net)->mib.statname##_statistics, (field));\
 230})
 231
 232#define _DEVADD(net, statname, mod, idev, field, val)			\
 233({									\
 234	struct inet6_dev *_idev = (idev);				\
 235	if (likely(_idev != NULL))					\
 236		mod##SNMP_ADD_STATS((_idev)->stats.statname, (field), (val)); \
 237	mod##SNMP_ADD_STATS((net)->mib.statname##_statistics, (field), (val));\
 238})
 239
 240#define _DEVUPD(net, statname, mod, idev, field, val)			\
 241({									\
 242	struct inet6_dev *_idev = (idev);				\
 243	if (likely(_idev != NULL))					\
 244		mod##SNMP_UPD_PO_STATS((_idev)->stats.statname, field, (val)); \
 245	mod##SNMP_UPD_PO_STATS((net)->mib.statname##_statistics, field, (val));\
 246})
 247
 248/* MIBs */
 249
 250#define IP6_INC_STATS(net, idev,field)		\
 251		_DEVINC(net, ipv6, , idev, field)
 252#define __IP6_INC_STATS(net, idev,field)	\
 253		_DEVINC(net, ipv6, __, idev, field)
 254#define IP6_ADD_STATS(net, idev,field,val)	\
 255		_DEVADD(net, ipv6, , idev, field, val)
 256#define __IP6_ADD_STATS(net, idev,field,val)	\
 257		_DEVADD(net, ipv6, __, idev, field, val)
 258#define IP6_UPD_PO_STATS(net, idev,field,val)   \
 259		_DEVUPD(net, ipv6, , idev, field, val)
 260#define __IP6_UPD_PO_STATS(net, idev,field,val)   \
 261		_DEVUPD(net, ipv6, __, idev, field, val)
 262#define ICMP6_INC_STATS(net, idev, field)	\
 263		_DEVINCATOMIC(net, icmpv6, , idev, field)
 264#define __ICMP6_INC_STATS(net, idev, field)	\
 265		_DEVINCATOMIC(net, icmpv6, __, idev, field)
 266
 267#define ICMP6MSGOUT_INC_STATS(net, idev, field)		\
 268	_DEVINC_ATOMIC_ATOMIC(net, icmpv6msg, idev, field +256)
 269#define ICMP6MSGIN_INC_STATS(net, idev, field)	\
 270	_DEVINC_ATOMIC_ATOMIC(net, icmpv6msg, idev, field)
 271
 272struct ip6_ra_chain {
 273	struct ip6_ra_chain	*next;
 274	struct sock		*sk;
 275	int			sel;
 276	void			(*destructor)(struct sock *);
 277};
 278
 279extern struct ip6_ra_chain	*ip6_ra_chain;
 280extern rwlock_t ip6_ra_lock;
 281
 282/*
 283   This structure is prepared by protocol, when parsing
 284   ancillary data and passed to IPv6.
 285 */
 286
 287struct ipv6_txoptions {
 288	refcount_t		refcnt;
 289	/* Length of this structure */
 290	int			tot_len;
 291
 292	/* length of extension headers   */
 293
 294	__u16			opt_flen;	/* after fragment hdr */
 295	__u16			opt_nflen;	/* before fragment hdr */
 296
 297	struct ipv6_opt_hdr	*hopopt;
 298	struct ipv6_opt_hdr	*dst0opt;
 299	struct ipv6_rt_hdr	*srcrt;	/* Routing Header */
 300	struct ipv6_opt_hdr	*dst1opt;
 301	struct rcu_head		rcu;
 302	/* Option buffer, as read by IPV6_PKTOPTIONS, starts here. */
 303};
 304
 305/* flowlabel_reflect sysctl values */
 306enum flowlabel_reflect {
 307	FLOWLABEL_REFLECT_ESTABLISHED		= 1,
 308	FLOWLABEL_REFLECT_TCP_RESET		= 2,
 309	FLOWLABEL_REFLECT_ICMPV6_ECHO_REPLIES	= 4,
 310};
 311
 312struct ip6_flowlabel {
 313	struct ip6_flowlabel __rcu *next;
 314	__be32			label;
 315	atomic_t		users;
 316	struct in6_addr		dst;
 317	struct ipv6_txoptions	*opt;
 318	unsigned long		linger;
 319	struct rcu_head		rcu;
 320	u8			share;
 321	union {
 322		struct pid *pid;
 323		kuid_t uid;
 324	} owner;
 325	unsigned long		lastuse;
 326	unsigned long		expires;
 327	struct net		*fl_net;
 328};
 329
 330#define IPV6_FLOWINFO_MASK		cpu_to_be32(0x0FFFFFFF)
 331#define IPV6_FLOWLABEL_MASK		cpu_to_be32(0x000FFFFF)
 332#define IPV6_FLOWLABEL_STATELESS_FLAG	cpu_to_be32(0x00080000)
 333
 334#define IPV6_TCLASS_MASK (IPV6_FLOWINFO_MASK & ~IPV6_FLOWLABEL_MASK)
 335#define IPV6_TCLASS_SHIFT	20
 336
 337struct ipv6_fl_socklist {
 338	struct ipv6_fl_socklist	__rcu	*next;
 339	struct ip6_flowlabel		*fl;
 340	struct rcu_head			rcu;
 341};
 342
 343struct ipcm6_cookie {
 344	struct sockcm_cookie sockc;
 345	__s16 hlimit;
 346	__s16 tclass;
 347	__s8  dontfrag;
 348	struct ipv6_txoptions *opt;
 349	__u16 gso_size;
 350};
 351
 352static inline void ipcm6_init(struct ipcm6_cookie *ipc6)
 353{
 354	*ipc6 = (struct ipcm6_cookie) {
 355		.hlimit = -1,
 356		.tclass = -1,
 357		.dontfrag = -1,
 358	};
 359}
 360
 361static inline void ipcm6_init_sk(struct ipcm6_cookie *ipc6,
 362				 const struct ipv6_pinfo *np)
 363{
 364	*ipc6 = (struct ipcm6_cookie) {
 365		.hlimit = -1,
 366		.tclass = np->tclass,
 367		.dontfrag = np->dontfrag,
 368	};
 369}
 370
 371static inline struct ipv6_txoptions *txopt_get(const struct ipv6_pinfo *np)
 372{
 373	struct ipv6_txoptions *opt;
 374
 375	rcu_read_lock();
 376	opt = rcu_dereference(np->opt);
 377	if (opt) {
 378		if (!refcount_inc_not_zero(&opt->refcnt))
 379			opt = NULL;
 380		else
 381			opt = rcu_pointer_handoff(opt);
 382	}
 383	rcu_read_unlock();
 384	return opt;
 385}
 386
 387static inline void txopt_put(struct ipv6_txoptions *opt)
 388{
 389	if (opt && refcount_dec_and_test(&opt->refcnt))
 390		kfree_rcu(opt, rcu);
 391}
 392
 393struct ip6_flowlabel *__fl6_sock_lookup(struct sock *sk, __be32 label);
 394
 395extern struct static_key_false_deferred ipv6_flowlabel_exclusive;
 396static inline struct ip6_flowlabel *fl6_sock_lookup(struct sock *sk,
 397						    __be32 label)
 398{
 399	if (static_branch_unlikely(&ipv6_flowlabel_exclusive.key))
 400		return __fl6_sock_lookup(sk, label) ? : ERR_PTR(-ENOENT);
 401
 402	return NULL;
 403}
 404
 405struct ipv6_txoptions *fl6_merge_options(struct ipv6_txoptions *opt_space,
 406					 struct ip6_flowlabel *fl,
 407					 struct ipv6_txoptions *fopt);
 408void fl6_free_socklist(struct sock *sk);
 409int ipv6_flowlabel_opt(struct sock *sk, char __user *optval, int optlen);
 410int ipv6_flowlabel_opt_get(struct sock *sk, struct in6_flowlabel_req *freq,
 411			   int flags);
 412int ip6_flowlabel_init(void);
 413void ip6_flowlabel_cleanup(void);
 414bool ip6_autoflowlabel(struct net *net, const struct ipv6_pinfo *np);
 415
 416static inline void fl6_sock_release(struct ip6_flowlabel *fl)
 417{
 418	if (fl)
 419		atomic_dec(&fl->users);
 420}
 421
 422void icmpv6_notify(struct sk_buff *skb, u8 type, u8 code, __be32 info);
 423
 424void icmpv6_push_pending_frames(struct sock *sk, struct flowi6 *fl6,
 425				struct icmp6hdr *thdr, int len);
 426
 427int ip6_ra_control(struct sock *sk, int sel);
 428
 429int ipv6_parse_hopopts(struct sk_buff *skb);
 430
 431struct ipv6_txoptions *ipv6_dup_options(struct sock *sk,
 432					struct ipv6_txoptions *opt);
 433struct ipv6_txoptions *ipv6_renew_options(struct sock *sk,
 434					  struct ipv6_txoptions *opt,
 435					  int newtype,
 436					  struct ipv6_opt_hdr *newopt);
 437struct ipv6_txoptions *ipv6_fixup_options(struct ipv6_txoptions *opt_space,
 438					  struct ipv6_txoptions *opt);
 439
 440bool ipv6_opt_accepted(const struct sock *sk, const struct sk_buff *skb,
 441		       const struct inet6_skb_parm *opt);
 442struct ipv6_txoptions *ipv6_update_options(struct sock *sk,
 443					   struct ipv6_txoptions *opt);
 444
 445static inline bool ipv6_accept_ra(struct inet6_dev *idev)
 446{
 447	/* If forwarding is enabled, RA are not accepted unless the special
 448	 * hybrid mode (accept_ra=2) is enabled.
 449	 */
 450	return idev->cnf.forwarding ? idev->cnf.accept_ra == 2 :
 451	    idev->cnf.accept_ra;
 452}
 453
 454#define IPV6_FRAG_HIGH_THRESH	(4 * 1024*1024)	/* 4194304 */
 455#define IPV6_FRAG_LOW_THRESH	(3 * 1024*1024)	/* 3145728 */
 456#define IPV6_FRAG_TIMEOUT	(60 * HZ)	/* 60 seconds */
 457
 458int __ipv6_addr_type(const struct in6_addr *addr);
 459static inline int ipv6_addr_type(const struct in6_addr *addr)
 460{
 461	return __ipv6_addr_type(addr) & 0xffff;
 462}
 463
 464static inline int ipv6_addr_scope(const struct in6_addr *addr)
 465{
 466	return __ipv6_addr_type(addr) & IPV6_ADDR_SCOPE_MASK;
 467}
 468
 469static inline int __ipv6_addr_src_scope(int type)
 470{
 471	return (type == IPV6_ADDR_ANY) ? __IPV6_ADDR_SCOPE_INVALID : (type >> 16);
 472}
 473
 474static inline int ipv6_addr_src_scope(const struct in6_addr *addr)
 475{
 476	return __ipv6_addr_src_scope(__ipv6_addr_type(addr));
 477}
 478
 479static inline bool __ipv6_addr_needs_scope_id(int type)
 480{
 481	return type & IPV6_ADDR_LINKLOCAL ||
 482	       (type & IPV6_ADDR_MULTICAST &&
 483		(type & (IPV6_ADDR_LOOPBACK|IPV6_ADDR_LINKLOCAL)));
 484}
 485
 486static inline __u32 ipv6_iface_scope_id(const struct in6_addr *addr, int iface)
 487{
 488	return __ipv6_addr_needs_scope_id(__ipv6_addr_type(addr)) ? iface : 0;
 489}
 490
 491static inline int ipv6_addr_cmp(const struct in6_addr *a1, const struct in6_addr *a2)
 492{
 493	return memcmp(a1, a2, sizeof(struct in6_addr));
 494}
 495
 496static inline bool
 497ipv6_masked_addr_cmp(const struct in6_addr *a1, const struct in6_addr *m,
 498		     const struct in6_addr *a2)
 499{
 500#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 501	const unsigned long *ul1 = (const unsigned long *)a1;
 502	const unsigned long *ulm = (const unsigned long *)m;
 503	const unsigned long *ul2 = (const unsigned long *)a2;
 504
 505	return !!(((ul1[0] ^ ul2[0]) & ulm[0]) |
 506		  ((ul1[1] ^ ul2[1]) & ulm[1]));
 507#else
 508	return !!(((a1->s6_addr32[0] ^ a2->s6_addr32[0]) & m->s6_addr32[0]) |
 509		  ((a1->s6_addr32[1] ^ a2->s6_addr32[1]) & m->s6_addr32[1]) |
 510		  ((a1->s6_addr32[2] ^ a2->s6_addr32[2]) & m->s6_addr32[2]) |
 511		  ((a1->s6_addr32[3] ^ a2->s6_addr32[3]) & m->s6_addr32[3]));
 512#endif
 513}
 514
 515static inline void ipv6_addr_prefix(struct in6_addr *pfx,
 516				    const struct in6_addr *addr,
 517				    int plen)
 518{
 519	/* caller must guarantee 0 <= plen <= 128 */
 520	int o = plen >> 3,
 521	    b = plen & 0x7;
 522
 523	memset(pfx->s6_addr, 0, sizeof(pfx->s6_addr));
 524	memcpy(pfx->s6_addr, addr, o);
 525	if (b != 0)
 526		pfx->s6_addr[o] = addr->s6_addr[o] & (0xff00 >> b);
 527}
 528
 529static inline void ipv6_addr_prefix_copy(struct in6_addr *addr,
 530					 const struct in6_addr *pfx,
 531					 int plen)
 532{
 533	/* caller must guarantee 0 <= plen <= 128 */
 534	int o = plen >> 3,
 535	    b = plen & 0x7;
 536
 537	memcpy(addr->s6_addr, pfx, o);
 538	if (b != 0) {
 539		addr->s6_addr[o] &= ~(0xff00 >> b);
 540		addr->s6_addr[o] |= (pfx->s6_addr[o] & (0xff00 >> b));
 541	}
 542}
 543
 544static inline void __ipv6_addr_set_half(__be32 *addr,
 545					__be32 wh, __be32 wl)
 546{
 547#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 548#if defined(__BIG_ENDIAN)
 549	if (__builtin_constant_p(wh) && __builtin_constant_p(wl)) {
 550		*(__force u64 *)addr = ((__force u64)(wh) << 32 | (__force u64)(wl));
 551		return;
 552	}
 553#elif defined(__LITTLE_ENDIAN)
 554	if (__builtin_constant_p(wl) && __builtin_constant_p(wh)) {
 555		*(__force u64 *)addr = ((__force u64)(wl) << 32 | (__force u64)(wh));
 556		return;
 557	}
 558#endif
 559#endif
 560	addr[0] = wh;
 561	addr[1] = wl;
 562}
 563
 564static inline void ipv6_addr_set(struct in6_addr *addr,
 565				     __be32 w1, __be32 w2,
 566				     __be32 w3, __be32 w4)
 567{
 568	__ipv6_addr_set_half(&addr->s6_addr32[0], w1, w2);
 569	__ipv6_addr_set_half(&addr->s6_addr32[2], w3, w4);
 570}
 571
 572static inline bool ipv6_addr_equal(const struct in6_addr *a1,
 573				   const struct in6_addr *a2)
 574{
 575#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 576	const unsigned long *ul1 = (const unsigned long *)a1;
 577	const unsigned long *ul2 = (const unsigned long *)a2;
 578
 579	return ((ul1[0] ^ ul2[0]) | (ul1[1] ^ ul2[1])) == 0UL;
 580#else
 581	return ((a1->s6_addr32[0] ^ a2->s6_addr32[0]) |
 582		(a1->s6_addr32[1] ^ a2->s6_addr32[1]) |
 583		(a1->s6_addr32[2] ^ a2->s6_addr32[2]) |
 584		(a1->s6_addr32[3] ^ a2->s6_addr32[3])) == 0;
 585#endif
 586}
 587
 588#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 589static inline bool __ipv6_prefix_equal64_half(const __be64 *a1,
 590					      const __be64 *a2,
 591					      unsigned int len)
 592{
 593	if (len && ((*a1 ^ *a2) & cpu_to_be64((~0UL) << (64 - len))))
 594		return false;
 595	return true;
 596}
 597
 598static inline bool ipv6_prefix_equal(const struct in6_addr *addr1,
 599				     const struct in6_addr *addr2,
 600				     unsigned int prefixlen)
 601{
 602	const __be64 *a1 = (const __be64 *)addr1;
 603	const __be64 *a2 = (const __be64 *)addr2;
 604
 605	if (prefixlen >= 64) {
 606		if (a1[0] ^ a2[0])
 607			return false;
 608		return __ipv6_prefix_equal64_half(a1 + 1, a2 + 1, prefixlen - 64);
 609	}
 610	return __ipv6_prefix_equal64_half(a1, a2, prefixlen);
 611}
 612#else
 613static inline bool ipv6_prefix_equal(const struct in6_addr *addr1,
 614				     const struct in6_addr *addr2,
 615				     unsigned int prefixlen)
 616{
 617	const __be32 *a1 = addr1->s6_addr32;
 618	const __be32 *a2 = addr2->s6_addr32;
 619	unsigned int pdw, pbi;
 620
 621	/* check complete u32 in prefix */
 622	pdw = prefixlen >> 5;
 623	if (pdw && memcmp(a1, a2, pdw << 2))
 624		return false;
 625
 626	/* check incomplete u32 in prefix */
 627	pbi = prefixlen & 0x1f;
 628	if (pbi && ((a1[pdw] ^ a2[pdw]) & htonl((0xffffffff) << (32 - pbi))))
 629		return false;
 630
 631	return true;
 632}
 633#endif
 634
 635static inline bool ipv6_addr_any(const struct in6_addr *a)
 636{
 637#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 638	const unsigned long *ul = (const unsigned long *)a;
 639
 640	return (ul[0] | ul[1]) == 0UL;
 641#else
 642	return (a->s6_addr32[0] | a->s6_addr32[1] |
 643		a->s6_addr32[2] | a->s6_addr32[3]) == 0;
 644#endif
 645}
 646
 647static inline u32 ipv6_addr_hash(const struct in6_addr *a)
 648{
 649#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 650	const unsigned long *ul = (const unsigned long *)a;
 651	unsigned long x = ul[0] ^ ul[1];
 652
 653	return (u32)(x ^ (x >> 32));
 654#else
 655	return (__force u32)(a->s6_addr32[0] ^ a->s6_addr32[1] ^
 656			     a->s6_addr32[2] ^ a->s6_addr32[3]);
 657#endif
 658}
 659
 660/* more secured version of ipv6_addr_hash() */
 661static inline u32 __ipv6_addr_jhash(const struct in6_addr *a, const u32 initval)
 662{
 663	u32 v = (__force u32)a->s6_addr32[0] ^ (__force u32)a->s6_addr32[1];
 664
 665	return jhash_3words(v,
 666			    (__force u32)a->s6_addr32[2],
 667			    (__force u32)a->s6_addr32[3],
 668			    initval);
 669}
 670
 671static inline bool ipv6_addr_loopback(const struct in6_addr *a)
 672{
 673#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 674	const __be64 *be = (const __be64 *)a;
 675
 676	return (be[0] | (be[1] ^ cpu_to_be64(1))) == 0UL;
 677#else
 678	return (a->s6_addr32[0] | a->s6_addr32[1] |
 679		a->s6_addr32[2] | (a->s6_addr32[3] ^ cpu_to_be32(1))) == 0;
 680#endif
 681}
 682
 683/*
 684 * Note that we must __force cast these to unsigned long to make sparse happy,
 685 * since all of the endian-annotated types are fixed size regardless of arch.
 686 */
 687static inline bool ipv6_addr_v4mapped(const struct in6_addr *a)
 688{
 689	return (
 690#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 691		*(unsigned long *)a |
 692#else
 693		(__force unsigned long)(a->s6_addr32[0] | a->s6_addr32[1]) |
 694#endif
 695		(__force unsigned long)(a->s6_addr32[2] ^
 696					cpu_to_be32(0x0000ffff))) == 0UL;
 697}
 698
 699static inline u32 ipv6_portaddr_hash(const struct net *net,
 700				     const struct in6_addr *addr6,
 701				     unsigned int port)
 702{
 703	unsigned int hash, mix = net_hash_mix(net);
 704
 705	if (ipv6_addr_any(addr6))
 706		hash = jhash_1word(0, mix);
 707	else if (ipv6_addr_v4mapped(addr6))
 708		hash = jhash_1word((__force u32)addr6->s6_addr32[3], mix);
 709	else
 710		hash = jhash2((__force u32 *)addr6->s6_addr32, 4, mix);
 711
 712	return hash ^ port;
 713}
 714
 715/*
 716 * Check for a RFC 4843 ORCHID address
 717 * (Overlay Routable Cryptographic Hash Identifiers)
 718 */
 719static inline bool ipv6_addr_orchid(const struct in6_addr *a)
 720{
 721	return (a->s6_addr32[0] & htonl(0xfffffff0)) == htonl(0x20010010);
 722}
 723
 724static inline bool ipv6_addr_is_multicast(const struct in6_addr *addr)
 725{
 726	return (addr->s6_addr32[0] & htonl(0xFF000000)) == htonl(0xFF000000);
 727}
 728
 729static inline void ipv6_addr_set_v4mapped(const __be32 addr,
 730					  struct in6_addr *v4mapped)
 731{
 732	ipv6_addr_set(v4mapped,
 733			0, 0,
 734			htonl(0x0000FFFF),
 735			addr);
 736}
 737
 738/*
 739 * find the first different bit between two addresses
 740 * length of address must be a multiple of 32bits
 741 */
 742static inline int __ipv6_addr_diff32(const void *token1, const void *token2, int addrlen)
 743{
 744	const __be32 *a1 = token1, *a2 = token2;
 745	int i;
 746
 747	addrlen >>= 2;
 748
 749	for (i = 0; i < addrlen; i++) {
 750		__be32 xb = a1[i] ^ a2[i];
 751		if (xb)
 752			return i * 32 + 31 - __fls(ntohl(xb));
 753	}
 754
 755	/*
 756	 *	we should *never* get to this point since that
 757	 *	would mean the addrs are equal
 758	 *
 759	 *	However, we do get to it 8) And exacly, when
 760	 *	addresses are equal 8)
 761	 *
 762	 *	ip route add 1111::/128 via ...
 763	 *	ip route add 1111::/64 via ...
 764	 *	and we are here.
 765	 *
 766	 *	Ideally, this function should stop comparison
 767	 *	at prefix length. It does not, but it is still OK,
 768	 *	if returned value is greater than prefix length.
 769	 *					--ANK (980803)
 770	 */
 771	return addrlen << 5;
 772}
 773
 774#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 775static inline int __ipv6_addr_diff64(const void *token1, const void *token2, int addrlen)
 776{
 777	const __be64 *a1 = token1, *a2 = token2;
 778	int i;
 779
 780	addrlen >>= 3;
 781
 782	for (i = 0; i < addrlen; i++) {
 783		__be64 xb = a1[i] ^ a2[i];
 784		if (xb)
 785			return i * 64 + 63 - __fls(be64_to_cpu(xb));
 786	}
 787
 788	return addrlen << 6;
 789}
 790#endif
 791
 792static inline int __ipv6_addr_diff(const void *token1, const void *token2, int addrlen)
 793{
 794#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
 795	if (__builtin_constant_p(addrlen) && !(addrlen & 7))
 796		return __ipv6_addr_diff64(token1, token2, addrlen);
 797#endif
 798	return __ipv6_addr_diff32(token1, token2, addrlen);
 799}
 800
 801static inline int ipv6_addr_diff(const struct in6_addr *a1, const struct in6_addr *a2)
 802{
 803	return __ipv6_addr_diff(a1, a2, sizeof(struct in6_addr));
 804}
 805
 806__be32 ipv6_select_ident(struct net *net,
 807			 const struct in6_addr *daddr,
 808			 const struct in6_addr *saddr);
 809__be32 ipv6_proxy_select_ident(struct net *net, struct sk_buff *skb);
 810
 811int ip6_dst_hoplimit(struct dst_entry *dst);
 812
 813static inline int ip6_sk_dst_hoplimit(struct ipv6_pinfo *np, struct flowi6 *fl6,
 814				      struct dst_entry *dst)
 815{
 816	int hlimit;
 817
 818	if (ipv6_addr_is_multicast(&fl6->daddr))
 819		hlimit = np->mcast_hops;
 820	else
 821		hlimit = np->hop_limit;
 822	if (hlimit < 0)
 823		hlimit = ip6_dst_hoplimit(dst);
 824	return hlimit;
 825}
 826
 827/* copy IPv6 saddr & daddr to flow_keys, possibly using 64bit load/store
 828 * Equivalent to :	flow->v6addrs.src = iph->saddr;
 829 *			flow->v6addrs.dst = iph->daddr;
 830 */
 831static inline void iph_to_flow_copy_v6addrs(struct flow_keys *flow,
 832					    const struct ipv6hdr *iph)
 833{
 834	BUILD_BUG_ON(offsetof(typeof(flow->addrs), v6addrs.dst) !=
 835		     offsetof(typeof(flow->addrs), v6addrs.src) +
 836		     sizeof(flow->addrs.v6addrs.src));
 837	memcpy(&flow->addrs.v6addrs, &iph->saddr, sizeof(flow->addrs.v6addrs));
 838	flow->control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
 839}
 840
 841#if IS_ENABLED(CONFIG_IPV6)
 842
 843static inline bool ipv6_can_nonlocal_bind(struct net *net,
 844					  struct inet_sock *inet)
 845{
 846	return net->ipv6.sysctl.ip_nonlocal_bind ||
 847		inet->freebind || inet->transparent;
 848}
 849
 850/* Sysctl settings for net ipv6.auto_flowlabels */
 851#define IP6_AUTO_FLOW_LABEL_OFF		0
 852#define IP6_AUTO_FLOW_LABEL_OPTOUT	1
 853#define IP6_AUTO_FLOW_LABEL_OPTIN	2
 854#define IP6_AUTO_FLOW_LABEL_FORCED	3
 855
 856#define IP6_AUTO_FLOW_LABEL_MAX		IP6_AUTO_FLOW_LABEL_FORCED
 857
 858#define IP6_DEFAULT_AUTO_FLOW_LABELS	IP6_AUTO_FLOW_LABEL_OPTOUT
 859
 860static inline __be32 ip6_make_flowlabel(struct net *net, struct sk_buff *skb,
 861					__be32 flowlabel, bool autolabel,
 862					struct flowi6 *fl6)
 863{
 864	u32 hash;
 865
 866	/* @flowlabel may include more than a flow label, eg, the traffic class.
 867	 * Here we want only the flow label value.
 868	 */
 869	flowlabel &= IPV6_FLOWLABEL_MASK;
 870
 871	if (flowlabel ||
 872	    net->ipv6.sysctl.auto_flowlabels == IP6_AUTO_FLOW_LABEL_OFF ||
 873	    (!autolabel &&
 874	     net->ipv6.sysctl.auto_flowlabels != IP6_AUTO_FLOW_LABEL_FORCED))
 875		return flowlabel;
 876
 877	hash = skb_get_hash_flowi6(skb, fl6);
 878
 879	/* Since this is being sent on the wire obfuscate hash a bit
 880	 * to minimize possbility that any useful information to an
 881	 * attacker is leaked. Only lower 20 bits are relevant.
 882	 */
 883	hash = rol32(hash, 16);
 884
 885	flowlabel = (__force __be32)hash & IPV6_FLOWLABEL_MASK;
 886
 887	if (net->ipv6.sysctl.flowlabel_state_ranges)
 888		flowlabel |= IPV6_FLOWLABEL_STATELESS_FLAG;
 889
 890	return flowlabel;
 891}
 892
 893static inline int ip6_default_np_autolabel(struct net *net)
 894{
 895	switch (net->ipv6.sysctl.auto_flowlabels) {
 896	case IP6_AUTO_FLOW_LABEL_OFF:
 897	case IP6_AUTO_FLOW_LABEL_OPTIN:
 898	default:
 899		return 0;
 900	case IP6_AUTO_FLOW_LABEL_OPTOUT:
 901	case IP6_AUTO_FLOW_LABEL_FORCED:
 902		return 1;
 903	}
 904}
 905#else
 906static inline void ip6_set_txhash(struct sock *sk) { }
 907static inline __be32 ip6_make_flowlabel(struct net *net, struct sk_buff *skb,
 908					__be32 flowlabel, bool autolabel,
 909					struct flowi6 *fl6)
 910{
 911	return flowlabel;
 912}
 913static inline int ip6_default_np_autolabel(struct net *net)
 914{
 915	return 0;
 916}
 917#endif
 918
 919#if IS_ENABLED(CONFIG_IPV6)
 920static inline int ip6_multipath_hash_policy(const struct net *net)
 921{
 922	return net->ipv6.sysctl.multipath_hash_policy;
 923}
 924#else
 925static inline int ip6_multipath_hash_policy(const struct net *net)
 926{
 927	return 0;
 928}
 929#endif
 930
 931/*
 932 *	Header manipulation
 933 */
 934static inline void ip6_flow_hdr(struct ipv6hdr *hdr, unsigned int tclass,
 935				__be32 flowlabel)
 936{
 937	*(__be32 *)hdr = htonl(0x60000000 | (tclass << 20)) | flowlabel;
 938}
 939
 940static inline __be32 ip6_flowinfo(const struct ipv6hdr *hdr)
 941{
 942	return *(__be32 *)hdr & IPV6_FLOWINFO_MASK;
 943}
 944
 945static inline __be32 ip6_flowlabel(const struct ipv6hdr *hdr)
 946{
 947	return *(__be32 *)hdr & IPV6_FLOWLABEL_MASK;
 948}
 949
 950static inline u8 ip6_tclass(__be32 flowinfo)
 951{
 952	return ntohl(flowinfo & IPV6_TCLASS_MASK) >> IPV6_TCLASS_SHIFT;
 953}
 954
 955static inline __be32 ip6_make_flowinfo(unsigned int tclass, __be32 flowlabel)
 956{
 957	return htonl(tclass << IPV6_TCLASS_SHIFT) | flowlabel;
 958}
 959
 960static inline __be32 flowi6_get_flowlabel(const struct flowi6 *fl6)
 961{
 962	return fl6->flowlabel & IPV6_FLOWLABEL_MASK;
 963}
 964
 965/*
 966 *	Prototypes exported by ipv6
 967 */
 968
 969/*
 970 *	rcv function (called from netdevice level)
 971 */
 972
 973int ipv6_rcv(struct sk_buff *skb, struct net_device *dev,
 974	     struct packet_type *pt, struct net_device *orig_dev);
 975void ipv6_list_rcv(struct list_head *head, struct packet_type *pt,
 976		   struct net_device *orig_dev);
 977
 978int ip6_rcv_finish(struct net *net, struct sock *sk, struct sk_buff *skb);
 979
 980/*
 981 *	upper-layer output functions
 982 */
 983int ip6_xmit(const struct sock *sk, struct sk_buff *skb, struct flowi6 *fl6,
 984	     __u32 mark, struct ipv6_txoptions *opt, int tclass, u32 priority);
 985
 986int ip6_find_1stfragopt(struct sk_buff *skb, u8 **nexthdr);
 987
 988int ip6_append_data(struct sock *sk,
 989		    int getfrag(void *from, char *to, int offset, int len,
 990				int odd, struct sk_buff *skb),
 991		    void *from, int length, int transhdrlen,
 992		    struct ipcm6_cookie *ipc6, struct flowi6 *fl6,
 993		    struct rt6_info *rt, unsigned int flags);
 994
 995int ip6_push_pending_frames(struct sock *sk);
 996
 997void ip6_flush_pending_frames(struct sock *sk);
 998
 999int ip6_send_skb(struct sk_buff *skb);
1000
1001struct sk_buff *__ip6_make_skb(struct sock *sk, struct sk_buff_head *queue,
1002			       struct inet_cork_full *cork,
1003			       struct inet6_cork *v6_cork);
1004struct sk_buff *ip6_make_skb(struct sock *sk,
1005			     int getfrag(void *from, char *to, int offset,
1006					 int len, int odd, struct sk_buff *skb),
1007			     void *from, int length, int transhdrlen,
1008			     struct ipcm6_cookie *ipc6, struct flowi6 *fl6,
1009			     struct rt6_info *rt, unsigned int flags,
1010			     struct inet_cork_full *cork);
1011
1012static inline struct sk_buff *ip6_finish_skb(struct sock *sk)
1013{
1014	return __ip6_make_skb(sk, &sk->sk_write_queue, &inet_sk(sk)->cork,
1015			      &inet6_sk(sk)->cork);
1016}
1017
1018int ip6_dst_lookup(struct net *net, struct sock *sk, struct dst_entry **dst,
1019		   struct flowi6 *fl6);
1020struct dst_entry *ip6_dst_lookup_flow(const struct sock *sk, struct flowi6 *fl6,
1021				      const struct in6_addr *final_dst);
1022struct dst_entry *ip6_sk_dst_lookup_flow(struct sock *sk, struct flowi6 *fl6,
1023					 const struct in6_addr *final_dst,
1024					 bool connected);
1025struct dst_entry *ip6_blackhole_route(struct net *net,
1026				      struct dst_entry *orig_dst);
1027
1028/*
1029 *	skb processing functions
1030 */
1031
1032int ip6_output(struct net *net, struct sock *sk, struct sk_buff *skb);
1033int ip6_forward(struct sk_buff *skb);
1034int ip6_input(struct sk_buff *skb);
1035int ip6_mc_input(struct sk_buff *skb);
1036void ip6_protocol_deliver_rcu(struct net *net, struct sk_buff *skb, int nexthdr,
1037			      bool have_final);
1038
1039int __ip6_local_out(struct net *net, struct sock *sk, struct sk_buff *skb);
1040int ip6_local_out(struct net *net, struct sock *sk, struct sk_buff *skb);
1041
1042/*
1043 *	Extension header (options) processing
1044 */
1045
1046void ipv6_push_nfrag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt,
1047			  u8 *proto, struct in6_addr **daddr_p,
1048			  struct in6_addr *saddr);
1049void ipv6_push_frag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt,
1050			 u8 *proto);
1051
1052int ipv6_skip_exthdr(const struct sk_buff *, int start, u8 *nexthdrp,
1053		     __be16 *frag_offp);
1054
1055bool ipv6_ext_hdr(u8 nexthdr);
1056
1057enum {
1058	IP6_FH_F_FRAG		= (1 << 0),
1059	IP6_FH_F_AUTH		= (1 << 1),
1060	IP6_FH_F_SKIP_RH	= (1 << 2),
1061};
1062
1063/* find specified header and get offset to it */
1064int ipv6_find_hdr(const struct sk_buff *skb, unsigned int *offset, int target,
1065		  unsigned short *fragoff, int *fragflg);
1066
1067int ipv6_find_tlv(const struct sk_buff *skb, int offset, int type);
1068
1069struct in6_addr *fl6_update_dst(struct flowi6 *fl6,
1070				const struct ipv6_txoptions *opt,
1071				struct in6_addr *orig);
1072
1073/*
1074 *	socket options (ipv6_sockglue.c)
1075 */
1076
1077int ipv6_setsockopt(struct sock *sk, int level, int optname,
1078		    char __user *optval, unsigned int optlen);
1079int ipv6_getsockopt(struct sock *sk, int level, int optname,
1080		    char __user *optval, int __user *optlen);
1081int compat_ipv6_setsockopt(struct sock *sk, int level, int optname,
1082			   char __user *optval, unsigned int optlen);
1083int compat_ipv6_getsockopt(struct sock *sk, int level, int optname,
1084			   char __user *optval, int __user *optlen);
1085
1086int __ip6_datagram_connect(struct sock *sk, struct sockaddr *addr,
1087			   int addr_len);
1088int ip6_datagram_connect(struct sock *sk, struct sockaddr *addr, int addr_len);
1089int ip6_datagram_connect_v6_only(struct sock *sk, struct sockaddr *addr,
1090				 int addr_len);
1091int ip6_datagram_dst_update(struct sock *sk, bool fix_sk_saddr);
1092void ip6_datagram_release_cb(struct sock *sk);
1093
1094int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len,
1095		    int *addr_len);
1096int ipv6_recv_rxpmtu(struct sock *sk, struct msghdr *msg, int len,
1097		     int *addr_len);
1098void ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err, __be16 port,
1099		     u32 info, u8 *payload);
1100void ipv6_local_error(struct sock *sk, int err, struct flowi6 *fl6, u32 info);
1101void ipv6_local_rxpmtu(struct sock *sk, struct flowi6 *fl6, u32 mtu);
1102
1103int inet6_release(struct socket *sock);
1104int inet6_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len);
1105int inet6_getname(struct socket *sock, struct sockaddr *uaddr,
1106		  int peer);
1107int inet6_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg);
1108
1109int inet6_hash_connect(struct inet_timewait_death_row *death_row,
1110			      struct sock *sk);
1111
1112/*
1113 * reassembly.c
1114 */
1115extern const struct proto_ops inet6_stream_ops;
1116extern const struct proto_ops inet6_dgram_ops;
1117extern const struct proto_ops inet6_sockraw_ops;
1118
1119struct group_source_req;
1120struct group_filter;
1121
1122int ip6_mc_source(int add, int omode, struct sock *sk,
1123		  struct group_source_req *pgsr);
1124int ip6_mc_msfilter(struct sock *sk, struct group_filter *gsf);
1125int ip6_mc_msfget(struct sock *sk, struct group_filter *gsf,
1126		  struct group_filter __user *optval, int __user *optlen);
1127
1128#ifdef CONFIG_PROC_FS
1129int ac6_proc_init(struct net *net);
1130void ac6_proc_exit(struct net *net);
1131int raw6_proc_init(void);
1132void raw6_proc_exit(void);
1133int tcp6_proc_init(struct net *net);
1134void tcp6_proc_exit(struct net *net);
1135int udp6_proc_init(struct net *net);
1136void udp6_proc_exit(struct net *net);
1137int udplite6_proc_init(void);
1138void udplite6_proc_exit(void);
1139int ipv6_misc_proc_init(void);
1140void ipv6_misc_proc_exit(void);
1141int snmp6_register_dev(struct inet6_dev *idev);
1142int snmp6_unregister_dev(struct inet6_dev *idev);
1143
1144#else
1145static inline int ac6_proc_init(struct net *net) { return 0; }
1146static inline void ac6_proc_exit(struct net *net) { }
1147static inline int snmp6_register_dev(struct inet6_dev *idev) { return 0; }
1148static inline int snmp6_unregister_dev(struct inet6_dev *idev) { return 0; }
1149#endif
1150
1151#ifdef CONFIG_SYSCTL
1152struct ctl_table *ipv6_icmp_sysctl_init(struct net *net);
1153struct ctl_table *ipv6_route_sysctl_init(struct net *net);
1154int ipv6_sysctl_register(void);
1155void ipv6_sysctl_unregister(void);
1156#endif
1157
1158int ipv6_sock_mc_join(struct sock *sk, int ifindex,
1159		      const struct in6_addr *addr);
1160int ipv6_sock_mc_join_ssm(struct sock *sk, int ifindex,
1161			  const struct in6_addr *addr, unsigned int mode);
1162int ipv6_sock_mc_drop(struct sock *sk, int ifindex,
1163		      const struct in6_addr *addr);
1164#endif /* _NET_IPV6_H */