Initial import

1 files changed, 947 insertions, 0 deletions

diff --git a/include/net/ipv6.h b/include/net/ipv6.h
new file mode 100644
index 000000000..eec8ad3c9
--- /dev/null
+++ b/include/net/ipv6.h
@@ -0,0 +1,947 @@
+/*
+ *	Linux INET6 implementation
+ *
+ *	Authors:
+ *	Pedro Roque		<roque@di.fc.ul.pt>
+ *
+ *	This program is free software; you can redistribute it and/or
+ *      modify it under the terms of the GNU General Public License
+ *      as published by the Free Software Foundation; either version
+ *      2 of the License, or (at your option) any later version.
+ */
+
+#ifndef _NET_IPV6_H
+#define _NET_IPV6_H
+
+#include <linux/ipv6.h>
+#include <linux/hardirq.h>
+#include <linux/jhash.h>
+#include <net/if_inet6.h>
+#include <net/ndisc.h>
+#include <net/flow.h>
+#include <net/flow_keys.h>
+#include <net/snmp.h>
+
+#define SIN6_LEN_RFC2133	24
+
+#define IPV6_MAXPLEN		65535
+
+/*
+ *	NextHeader field of IPv6 header
+ */
+
+#define NEXTHDR_HOP		0	/* Hop-by-hop option header. */
+#define NEXTHDR_TCP		6	/* TCP segment. */
+#define NEXTHDR_UDP		17	/* UDP message. */
+#define NEXTHDR_IPV6		41	/* IPv6 in IPv6 */
+#define NEXTHDR_ROUTING		43	/* Routing header. */
+#define NEXTHDR_FRAGMENT	44	/* Fragmentation/reassembly header. */
+#define NEXTHDR_GRE		47	/* GRE header. */
+#define NEXTHDR_ESP		50	/* Encapsulating security payload. */
+#define NEXTHDR_AUTH		51	/* Authentication header. */
+#define NEXTHDR_ICMP		58	/* ICMP for IPv6. */
+#define NEXTHDR_NONE		59	/* No next header */
+#define NEXTHDR_DEST		60	/* Destination options header. */
+#define NEXTHDR_SCTP		132	/* SCTP message. */
+#define NEXTHDR_MOBILITY	135	/* Mobility header. */
+
+#define NEXTHDR_MAX		255
+
+#define IPV6_DEFAULT_HOPLIMIT   64
+#define IPV6_DEFAULT_MCASTHOPS	1
+
+/*
+ *	Addr type
+ *	
+ *	type	-	unicast | multicast
+ *	scope	-	local	| site	    | global
+ *	v4	-	compat
+ *	v4mapped
+ *	any
+ *	loopback
+ */
+
+#define IPV6_ADDR_ANY		0x0000U
+
+#define IPV6_ADDR_UNICAST      	0x0001U	
+#define IPV6_ADDR_MULTICAST    	0x0002U	
+
+#define IPV6_ADDR_LOOPBACK	0x0010U
+#define IPV6_ADDR_LINKLOCAL	0x0020U
+#define IPV6_ADDR_SITELOCAL	0x0040U
+
+#define IPV6_ADDR_COMPATv4	0x0080U
+
+#define IPV6_ADDR_SCOPE_MASK	0x00f0U
+
+#define IPV6_ADDR_MAPPED	0x1000U
+
+/*
+ *	Addr scopes
+ */
+#define IPV6_ADDR_MC_SCOPE(a)	\
+	((a)->s6_addr[1] & 0x0f)	/* nonstandard */
+#define __IPV6_ADDR_SCOPE_INVALID	-1
+#define IPV6_ADDR_SCOPE_NODELOCAL	0x01
+#define IPV6_ADDR_SCOPE_LINKLOCAL	0x02
+#define IPV6_ADDR_SCOPE_SITELOCAL	0x05
+#define IPV6_ADDR_SCOPE_ORGLOCAL	0x08
+#define IPV6_ADDR_SCOPE_GLOBAL		0x0e
+
+/*
+ *	Addr flags
+ */
+#define IPV6_ADDR_MC_FLAG_TRANSIENT(a)	\
+	((a)->s6_addr[1] & 0x10)
+#define IPV6_ADDR_MC_FLAG_PREFIX(a)	\
+	((a)->s6_addr[1] & 0x20)
+#define IPV6_ADDR_MC_FLAG_RENDEZVOUS(a)	\
+	((a)->s6_addr[1] & 0x40)
+
+/*
+ *	fragmentation header
+ */
+
+struct frag_hdr {
+	__u8	nexthdr;
+	__u8	reserved;
+	__be16	frag_off;
+	__be32	identification;
+};
+
+#define	IP6_MF		0x0001
+#define	IP6_OFFSET	0xFFF8
+
+#define IP6_REPLY_MARK(net, mark) \
+	((net)->ipv6.sysctl.fwmark_reflect ? (mark) : 0)
+
+#include <net/sock.h>
+
+/* sysctls */
+extern int sysctl_mld_max_msf;
+extern int sysctl_mld_qrv;
+
+#define _DEVINC(net, statname, modifier, idev, field)			\
+({									\
+	struct inet6_dev *_idev = (idev);				\
+	if (likely(_idev != NULL))					\
+		SNMP_INC_STATS##modifier((_idev)->stats.statname, (field)); \
+	SNMP_INC_STATS##modifier((net)->mib.statname##_statistics, (field));\
+})
+
+/* per device counters are atomic_long_t */
+#define _DEVINCATOMIC(net, statname, modifier, idev, field)		\
+({									\
+	struct inet6_dev *_idev = (idev);				\
+	if (likely(_idev != NULL))					\
+		SNMP_INC_STATS_ATOMIC_LONG((_idev)->stats.statname##dev, (field)); \
+	SNMP_INC_STATS##modifier((net)->mib.statname##_statistics, (field));\
+})
+
+/* per device and per net counters are atomic_long_t */
+#define _DEVINC_ATOMIC_ATOMIC(net, statname, idev, field)		\
+({									\
+	struct inet6_dev *_idev = (idev);				\
+	if (likely(_idev != NULL))					\
+		SNMP_INC_STATS_ATOMIC_LONG((_idev)->stats.statname##dev, (field)); \
+	SNMP_INC_STATS_ATOMIC_LONG((net)->mib.statname##_statistics, (field));\
+})
+
+#define _DEVADD(net, statname, modifier, idev, field, val)		\
+({									\
+	struct inet6_dev *_idev = (idev);				\
+	if (likely(_idev != NULL))					\
+		SNMP_ADD_STATS##modifier((_idev)->stats.statname, (field), (val)); \
+	SNMP_ADD_STATS##modifier((net)->mib.statname##_statistics, (field), (val));\
+})
+
+#define _DEVUPD(net, statname, modifier, idev, field, val)		\
+({									\
+	struct inet6_dev *_idev = (idev);				\
+	if (likely(_idev != NULL))					\
+		SNMP_UPD_PO_STATS##modifier((_idev)->stats.statname, field, (val)); \
+	SNMP_UPD_PO_STATS##modifier((net)->mib.statname##_statistics, field, (val));\
+})
+
+/* MIBs */
+
+#define IP6_INC_STATS(net, idev,field)		\
+		_DEVINC(net, ipv6, 64, idev, field)
+#define IP6_INC_STATS_BH(net, idev,field)	\
+		_DEVINC(net, ipv6, 64_BH, idev, field)
+#define IP6_ADD_STATS(net, idev,field,val)	\
+		_DEVADD(net, ipv6, 64, idev, field, val)
+#define IP6_ADD_STATS_BH(net, idev,field,val)	\
+		_DEVADD(net, ipv6, 64_BH, idev, field, val)
+#define IP6_UPD_PO_STATS(net, idev,field,val)   \
+		_DEVUPD(net, ipv6, 64, idev, field, val)
+#define IP6_UPD_PO_STATS_BH(net, idev,field,val)   \
+		_DEVUPD(net, ipv6, 64_BH, idev, field, val)
+#define ICMP6_INC_STATS(net, idev, field)	\
+		_DEVINCATOMIC(net, icmpv6, , idev, field)
+#define ICMP6_INC_STATS_BH(net, idev, field)	\
+		_DEVINCATOMIC(net, icmpv6, _BH, idev, field)
+
+#define ICMP6MSGOUT_INC_STATS(net, idev, field)		\
+	_DEVINC_ATOMIC_ATOMIC(net, icmpv6msg, idev, field +256)
+#define ICMP6MSGOUT_INC_STATS_BH(net, idev, field)	\
+	_DEVINC_ATOMIC_ATOMIC(net, icmpv6msg, idev, field +256)
+#define ICMP6MSGIN_INC_STATS_BH(net, idev, field)	\
+	_DEVINC_ATOMIC_ATOMIC(net, icmpv6msg, idev, field)
+
+struct ip6_ra_chain {
+	struct ip6_ra_chain	*next;
+	struct sock		*sk;
+	int			sel;
+	void			(*destructor)(struct sock *);
+};
+
+extern struct ip6_ra_chain	*ip6_ra_chain;
+extern rwlock_t ip6_ra_lock;
+
+/*
+   This structure is prepared by protocol, when parsing
+   ancillary data and passed to IPv6.
+ */
+
+struct ipv6_txoptions {
+	/* Length of this structure */
+	int			tot_len;
+
+	/* length of extension headers   */
+
+	__u16			opt_flen;	/* after fragment hdr */
+	__u16			opt_nflen;	/* before fragment hdr */
+
+	struct ipv6_opt_hdr	*hopopt;
+	struct ipv6_opt_hdr	*dst0opt;
+	struct ipv6_rt_hdr	*srcrt;	/* Routing Header */
+	struct ipv6_opt_hdr	*dst1opt;
+
+	/* Option buffer, as read by IPV6_PKTOPTIONS, starts here. */
+};
+
+struct ip6_flowlabel {
+	struct ip6_flowlabel __rcu *next;
+	__be32			label;
+	atomic_t		users;
+	struct in6_addr		dst;
+	struct ipv6_txoptions	*opt;
+	unsigned long		linger;
+	struct rcu_head		rcu;
+	u8			share;
+	union {
+		struct pid *pid;
+		kuid_t uid;
+	} owner;
+	unsigned long		lastuse;
+	unsigned long		expires;
+	struct net		*fl_net;
+};
+
+#define IPV6_FLOWINFO_MASK	cpu_to_be32(0x0FFFFFFF)
+#define IPV6_FLOWLABEL_MASK	cpu_to_be32(0x000FFFFF)
+#define IPV6_TCLASS_MASK (IPV6_FLOWINFO_MASK & ~IPV6_FLOWLABEL_MASK)
+#define IPV6_TCLASS_SHIFT	20
+
+struct ipv6_fl_socklist {
+	struct ipv6_fl_socklist	__rcu	*next;
+	struct ip6_flowlabel		*fl;
+	struct rcu_head			rcu;
+};
+
+struct ip6_flowlabel *fl6_sock_lookup(struct sock *sk, __be32 label);
+struct ipv6_txoptions *fl6_merge_options(struct ipv6_txoptions *opt_space,
+					 struct ip6_flowlabel *fl,
+					 struct ipv6_txoptions *fopt);
+void fl6_free_socklist(struct sock *sk);
+int ipv6_flowlabel_opt(struct sock *sk, char __user *optval, int optlen);
+int ipv6_flowlabel_opt_get(struct sock *sk, struct in6_flowlabel_req *freq,
+			   int flags);
+int ip6_flowlabel_init(void);
+void ip6_flowlabel_cleanup(void);
+
+static inline void fl6_sock_release(struct ip6_flowlabel *fl)
+{
+	if (fl)
+		atomic_dec(&fl->users);
+}
+
+void icmpv6_notify(struct sk_buff *skb, u8 type, u8 code, __be32 info);
+
+int icmpv6_push_pending_frames(struct sock *sk, struct flowi6 *fl6,
+			       struct icmp6hdr *thdr, int len);
+
+int ip6_ra_control(struct sock *sk, int sel);
+
+int ipv6_parse_hopopts(struct sk_buff *skb);
+
+struct ipv6_txoptions *ipv6_dup_options(struct sock *sk,
+					struct ipv6_txoptions *opt);
+struct ipv6_txoptions *ipv6_renew_options(struct sock *sk,
+					  struct ipv6_txoptions *opt,
+					  int newtype,
+					  struct ipv6_opt_hdr __user *newopt,
+					  int newoptlen);
+struct ipv6_txoptions *ipv6_fixup_options(struct ipv6_txoptions *opt_space,
+					  struct ipv6_txoptions *opt);
+
+bool ipv6_opt_accepted(const struct sock *sk, const struct sk_buff *skb,
+		       const struct inet6_skb_parm *opt);
+
+static inline bool ipv6_accept_ra(struct inet6_dev *idev)
+{
+	/* If forwarding is enabled, RA are not accepted unless the special
+	 * hybrid mode (accept_ra=2) is enabled.
+	 */
+	return idev->cnf.forwarding ? idev->cnf.accept_ra == 2 :
+	    idev->cnf.accept_ra;
+}
+
+#if IS_ENABLED(CONFIG_IPV6)
+static inline int ip6_frag_mem(struct net *net)
+{
+	return sum_frag_mem_limit(&net->ipv6.frags);
+}
+#endif
+
+#define IPV6_FRAG_HIGH_THRESH	(4 * 1024*1024)	/* 4194304 */
+#define IPV6_FRAG_LOW_THRESH	(3 * 1024*1024)	/* 3145728 */
+#define IPV6_FRAG_TIMEOUT	(60 * HZ)	/* 60 seconds */
+
+int __ipv6_addr_type(const struct in6_addr *addr);
+static inline int ipv6_addr_type(const struct in6_addr *addr)
+{
+	return __ipv6_addr_type(addr) & 0xffff;
+}
+
+static inline int ipv6_addr_scope(const struct in6_addr *addr)
+{
+	return __ipv6_addr_type(addr) & IPV6_ADDR_SCOPE_MASK;
+}
+
+static inline int __ipv6_addr_src_scope(int type)
+{
+	return (type == IPV6_ADDR_ANY) ? __IPV6_ADDR_SCOPE_INVALID : (type >> 16);
+}
+
+static inline int ipv6_addr_src_scope(const struct in6_addr *addr)
+{
+	return __ipv6_addr_src_scope(__ipv6_addr_type(addr));
+}
+
+static inline bool __ipv6_addr_needs_scope_id(int type)
+{
+	return type & IPV6_ADDR_LINKLOCAL ||
+	       (type & IPV6_ADDR_MULTICAST &&
+		(type & (IPV6_ADDR_LOOPBACK|IPV6_ADDR_LINKLOCAL)));
+}
+
+static inline __u32 ipv6_iface_scope_id(const struct in6_addr *addr, int iface)
+{
+	return __ipv6_addr_needs_scope_id(__ipv6_addr_type(addr)) ? iface : 0;
+}
+
+static inline int ipv6_addr_cmp(const struct in6_addr *a1, const struct in6_addr *a2)
+{
+	return memcmp(a1, a2, sizeof(struct in6_addr));
+}
+
+static inline bool
+ipv6_masked_addr_cmp(const struct in6_addr *a1, const struct in6_addr *m,
+		     const struct in6_addr *a2)
+{
+#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
+	const unsigned long *ul1 = (const unsigned long *)a1;
+	const unsigned long *ulm = (const unsigned long *)m;
+	const unsigned long *ul2 = (const unsigned long *)a2;
+
+	return !!(((ul1[0] ^ ul2[0]) & ulm[0]) |
+		  ((ul1[1] ^ ul2[1]) & ulm[1]));
+#else
+	return !!(((a1->s6_addr32[0] ^ a2->s6_addr32[0]) & m->s6_addr32[0]) |
+		  ((a1->s6_addr32[1] ^ a2->s6_addr32[1]) & m->s6_addr32[1]) |
+		  ((a1->s6_addr32[2] ^ a2->s6_addr32[2]) & m->s6_addr32[2]) |
+		  ((a1->s6_addr32[3] ^ a2->s6_addr32[3]) & m->s6_addr32[3]));
+#endif
+}
+
+static inline void ipv6_addr_prefix(struct in6_addr *pfx, 
+				    const struct in6_addr *addr,
+				    int plen)
+{
+	/* caller must guarantee 0 <= plen <= 128 */
+	int o = plen >> 3,
+	    b = plen & 0x7;
+
+	memset(pfx->s6_addr, 0, sizeof(pfx->s6_addr));
+	memcpy(pfx->s6_addr, addr, o);
+	if (b != 0)
+		pfx->s6_addr[o] = addr->s6_addr[o] & (0xff00 >> b);
+}
+
+static inline void __ipv6_addr_set_half(__be32 *addr,
+					__be32 wh, __be32 wl)
+{
+#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
+#if defined(__BIG_ENDIAN)
+	if (__builtin_constant_p(wh) && __builtin_constant_p(wl)) {
+		*(__force u64 *)addr = ((__force u64)(wh) << 32 | (__force u64)(wl));
+		return;
+	}
+#elif defined(__LITTLE_ENDIAN)
+	if (__builtin_constant_p(wl) && __builtin_constant_p(wh)) {
+		*(__force u64 *)addr = ((__force u64)(wl) << 32 | (__force u64)(wh));
+		return;
+	}
+#endif
+#endif
+	addr[0] = wh;
+	addr[1] = wl;
+}
+
+static inline void ipv6_addr_set(struct in6_addr *addr, 
+				     __be32 w1, __be32 w2,
+				     __be32 w3, __be32 w4)
+{
+	__ipv6_addr_set_half(&addr->s6_addr32[0], w1, w2);
+	__ipv6_addr_set_half(&addr->s6_addr32[2], w3, w4);
+}
+
+static inline bool ipv6_addr_equal(const struct in6_addr *a1,
+				   const struct in6_addr *a2)
+{
+#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
+	const unsigned long *ul1 = (const unsigned long *)a1;
+	const unsigned long *ul2 = (const unsigned long *)a2;
+
+	return ((ul1[0] ^ ul2[0]) | (ul1[1] ^ ul2[1])) == 0UL;
+#else
+	return ((a1->s6_addr32[0] ^ a2->s6_addr32[0]) |
+		(a1->s6_addr32[1] ^ a2->s6_addr32[1]) |
+		(a1->s6_addr32[2] ^ a2->s6_addr32[2]) |
+		(a1->s6_addr32[3] ^ a2->s6_addr32[3])) == 0;
+#endif
+}
+
+#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
+static inline bool __ipv6_prefix_equal64_half(const __be64 *a1,
+					      const __be64 *a2,
+					      unsigned int len)
+{
+	if (len && ((*a1 ^ *a2) & cpu_to_be64((~0UL) << (64 - len))))
+		return false;
+	return true;
+}
+
+static inline bool ipv6_prefix_equal(const struct in6_addr *addr1,
+				     const struct in6_addr *addr2,
+				     unsigned int prefixlen)
+{
+	const __be64 *a1 = (const __be64 *)addr1;
+	const __be64 *a2 = (const __be64 *)addr2;
+
+	if (prefixlen >= 64) {
+		if (a1[0] ^ a2[0])
+			return false;
+		return __ipv6_prefix_equal64_half(a1 + 1, a2 + 1, prefixlen - 64);
+	}
+	return __ipv6_prefix_equal64_half(a1, a2, prefixlen);
+}
+#else
+static inline bool ipv6_prefix_equal(const struct in6_addr *addr1,
+				     const struct in6_addr *addr2,
+				     unsigned int prefixlen)
+{
+	const __be32 *a1 = addr1->s6_addr32;
+	const __be32 *a2 = addr2->s6_addr32;
+	unsigned int pdw, pbi;
+
+	/* check complete u32 in prefix */
+	pdw = prefixlen >> 5;
+	if (pdw && memcmp(a1, a2, pdw << 2))
+		return false;
+
+	/* check incomplete u32 in prefix */
+	pbi = prefixlen & 0x1f;
+	if (pbi && ((a1[pdw] ^ a2[pdw]) & htonl((0xffffffff) << (32 - pbi))))
+		return false;
+
+	return true;
+}
+#endif
+
+struct inet_frag_queue;
+
+enum ip6_defrag_users {
+	IP6_DEFRAG_LOCAL_DELIVER,
+	IP6_DEFRAG_CONNTRACK_IN,
+	__IP6_DEFRAG_CONNTRACK_IN	= IP6_DEFRAG_CONNTRACK_IN + USHRT_MAX,
+	IP6_DEFRAG_CONNTRACK_OUT,
+	__IP6_DEFRAG_CONNTRACK_OUT	= IP6_DEFRAG_CONNTRACK_OUT + USHRT_MAX,
+	IP6_DEFRAG_CONNTRACK_BRIDGE_IN,
+	__IP6_DEFRAG_CONNTRACK_BRIDGE_IN = IP6_DEFRAG_CONNTRACK_BRIDGE_IN + USHRT_MAX,
+};
+
+struct ip6_create_arg {
+	__be32 id;
+	u32 user;
+	const struct in6_addr *src;
+	const struct in6_addr *dst;
+	u8 ecn;
+};
+
+void ip6_frag_init(struct inet_frag_queue *q, const void *a);
+bool ip6_frag_match(const struct inet_frag_queue *q, const void *a);
+
+/*
+ *	Equivalent of ipv4 struct ip
+ */
+struct frag_queue {
+	struct inet_frag_queue	q;
+
+	__be32			id;		/* fragment id		*/
+	u32			user;
+	struct in6_addr		saddr;
+	struct in6_addr		daddr;
+
+	int			iif;
+	unsigned int		csum;
+	__u16			nhoffset;
+	u8			ecn;
+};
+
+void ip6_expire_frag_queue(struct net *net, struct frag_queue *fq,
+			   struct inet_frags *frags);
+
+static inline bool ipv6_addr_any(const struct in6_addr *a)
+{
+#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
+	const unsigned long *ul = (const unsigned long *)a;
+
+	return (ul[0] | ul[1]) == 0UL;
+#else
+	return (a->s6_addr32[0] | a->s6_addr32[1] |
+		a->s6_addr32[2] | a->s6_addr32[3]) == 0;
+#endif
+}
+
+static inline u32 ipv6_addr_hash(const struct in6_addr *a)
+{
+#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
+	const unsigned long *ul = (const unsigned long *)a;
+	unsigned long x = ul[0] ^ ul[1];
+
+	return (u32)(x ^ (x >> 32));
+#else
+	return (__force u32)(a->s6_addr32[0] ^ a->s6_addr32[1] ^
+			     a->s6_addr32[2] ^ a->s6_addr32[3]);
+#endif
+}
+
+/* more secured version of ipv6_addr_hash() */
+static inline u32 __ipv6_addr_jhash(const struct in6_addr *a, const u32 initval)
+{
+	u32 v = (__force u32)a->s6_addr32[0] ^ (__force u32)a->s6_addr32[1];
+
+	return jhash_3words(v,
+			    (__force u32)a->s6_addr32[2],
+			    (__force u32)a->s6_addr32[3],
+			    initval);
+}
+
+static inline bool ipv6_addr_loopback(const struct in6_addr *a)
+{
+#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
+	const __be64 *be = (const __be64 *)a;
+
+	return (be[0] | (be[1] ^ cpu_to_be64(1))) == 0UL;
+#else
+	return (a->s6_addr32[0] | a->s6_addr32[1] |
+		a->s6_addr32[2] | (a->s6_addr32[3] ^ cpu_to_be32(1))) == 0;
+#endif
+}
+
+/*
+ * Note that we must __force cast these to unsigned long to make sparse happy,
+ * since all of the endian-annotated types are fixed size regardless of arch.
+ */
+static inline bool ipv6_addr_v4mapped(const struct in6_addr *a)
+{
+	return (
+#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
+		*(unsigned long *)a |
+#else
+		(__force unsigned long)(a->s6_addr32[0] | a->s6_addr32[1]) |
+#endif
+		(__force unsigned long)(a->s6_addr32[2] ^
+					cpu_to_be32(0x0000ffff))) == 0UL;
+}
+
+/*
+ * Check for a RFC 4843 ORCHID address
+ * (Overlay Routable Cryptographic Hash Identifiers)
+ */
+static inline bool ipv6_addr_orchid(const struct in6_addr *a)
+{
+	return (a->s6_addr32[0] & htonl(0xfffffff0)) == htonl(0x20010010);
+}
+
+static inline bool ipv6_addr_is_multicast(const struct in6_addr *addr)
+{
+	return (addr->s6_addr32[0] & htonl(0xFF000000)) == htonl(0xFF000000);
+}
+
+static inline void ipv6_addr_set_v4mapped(const __be32 addr,
+					  struct in6_addr *v4mapped)
+{
+	ipv6_addr_set(v4mapped,
+			0, 0,
+			htonl(0x0000FFFF),
+			addr);
+}
+
+/*
+ * find the first different bit between two addresses
+ * length of address must be a multiple of 32bits
+ */
+static inline int __ipv6_addr_diff32(const void *token1, const void *token2, int addrlen)
+{
+	const __be32 *a1 = token1, *a2 = token2;
+	int i;
+
+	addrlen >>= 2;
+
+	for (i = 0; i < addrlen; i++) {
+		__be32 xb = a1[i] ^ a2[i];
+		if (xb)
+			return i * 32 + 31 - __fls(ntohl(xb));
+	}
+
+	/*
+	 *	we should *never* get to this point since that 
+	 *	would mean the addrs are equal
+	 *
+	 *	However, we do get to it 8) And exacly, when
+	 *	addresses are equal 8)
+	 *
+	 *	ip route add 1111::/128 via ...
+	 *	ip route add 1111::/64 via ...
+	 *	and we are here.
+	 *
+	 *	Ideally, this function should stop comparison
+	 *	at prefix length. It does not, but it is still OK,
+	 *	if returned value is greater than prefix length.
+	 *					--ANK (980803)
+	 */
+	return addrlen << 5;
+}
+
+#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
+static inline int __ipv6_addr_diff64(const void *token1, const void *token2, int addrlen)
+{
+	const __be64 *a1 = token1, *a2 = token2;
+	int i;
+
+	addrlen >>= 3;
+
+	for (i = 0; i < addrlen; i++) {
+		__be64 xb = a1[i] ^ a2[i];
+		if (xb)
+			return i * 64 + 63 - __fls(be64_to_cpu(xb));
+	}
+
+	return addrlen << 6;
+}
+#endif
+
+static inline int __ipv6_addr_diff(const void *token1, const void *token2, int addrlen)
+{
+#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
+	if (__builtin_constant_p(addrlen) && !(addrlen & 7))
+		return __ipv6_addr_diff64(token1, token2, addrlen);
+#endif
+	return __ipv6_addr_diff32(token1, token2, addrlen);
+}
+
+static inline int ipv6_addr_diff(const struct in6_addr *a1, const struct in6_addr *a2)
+{
+	return __ipv6_addr_diff(a1, a2, sizeof(struct in6_addr));
+}
+
+void ipv6_select_ident(struct net *net, struct frag_hdr *fhdr,
+		       struct rt6_info *rt);
+void ipv6_proxy_select_ident(struct net *net, struct sk_buff *skb);
+
+int ip6_dst_hoplimit(struct dst_entry *dst);
+
+static inline int ip6_sk_dst_hoplimit(struct ipv6_pinfo *np, struct flowi6 *fl6,
+				      struct dst_entry *dst)
+{
+	int hlimit;
+
+	if (ipv6_addr_is_multicast(&fl6->daddr))
+		hlimit = np->mcast_hops;
+	else
+		hlimit = np->hop_limit;
+	if (hlimit < 0)
+		hlimit = ip6_dst_hoplimit(dst);
+	return hlimit;
+}
+
+#if IS_ENABLED(CONFIG_IPV6)
+static inline void ip6_set_txhash(struct sock *sk)
+{
+	struct inet_sock *inet = inet_sk(sk);
+	struct ipv6_pinfo *np = inet6_sk(sk);
+	struct flow_keys keys;
+
+	keys.src = (__force __be32)ipv6_addr_hash(&np->saddr);
+	keys.dst = (__force __be32)ipv6_addr_hash(&sk->sk_v6_daddr);
+	keys.port16[0] = inet->inet_sport;
+	keys.port16[1] = inet->inet_dport;
+
+	sk->sk_txhash = flow_hash_from_keys(&keys);
+}
+
+static inline __be32 ip6_make_flowlabel(struct net *net, struct sk_buff *skb,
+					__be32 flowlabel, bool autolabel)
+{
+	if (!flowlabel && (autolabel || net->ipv6.sysctl.auto_flowlabels)) {
+		u32 hash;
+
+		hash = skb_get_hash(skb);
+
+		/* Since this is being sent on the wire obfuscate hash a bit
+		 * to minimize possbility that any useful information to an
+		 * attacker is leaked. Only lower 20 bits are relevant.
+		 */
+		hash ^= hash >> 12;
+
+		flowlabel = (__force __be32)hash & IPV6_FLOWLABEL_MASK;
+	}
+
+	return flowlabel;
+}
+#else
+static inline void ip6_set_txhash(struct sock *sk) { }
+static inline __be32 ip6_make_flowlabel(struct net *net, struct sk_buff *skb,
+					__be32 flowlabel, bool autolabel)
+{
+	return flowlabel;
+}
+#endif
+
+
+/*
+ *	Header manipulation
+ */
+static inline void ip6_flow_hdr(struct ipv6hdr *hdr, unsigned int tclass,
+				__be32 flowlabel)
+{
+	*(__be32 *)hdr = htonl(0x60000000 | (tclass << 20)) | flowlabel;
+}
+
+static inline __be32 ip6_flowinfo(const struct ipv6hdr *hdr)
+{
+	return *(__be32 *)hdr & IPV6_FLOWINFO_MASK;
+}
+
+static inline __be32 ip6_flowlabel(const struct ipv6hdr *hdr)
+{
+	return *(__be32 *)hdr & IPV6_FLOWLABEL_MASK;
+}
+
+static inline u8 ip6_tclass(__be32 flowinfo)
+{
+	return ntohl(flowinfo & IPV6_TCLASS_MASK) >> IPV6_TCLASS_SHIFT;
+}
+/*
+ *	Prototypes exported by ipv6
+ */
+
+/*
+ *	rcv function (called from netdevice level)
+ */
+
+int ipv6_rcv(struct sk_buff *skb, struct net_device *dev,
+	     struct packet_type *pt, struct net_device *orig_dev);
+
+int ip6_rcv_finish(struct sock *sk, struct sk_buff *skb);
+
+/*
+ *	upper-layer output functions
+ */
+int ip6_xmit(struct sock *sk, struct sk_buff *skb, struct flowi6 *fl6,
+	     struct ipv6_txoptions *opt, int tclass);
+
+int ip6_find_1stfragopt(struct sk_buff *skb, u8 **nexthdr);
+
+int ip6_append_data(struct sock *sk,
+		    int getfrag(void *from, char *to, int offset, int len,
+				int odd, struct sk_buff *skb),
+		    void *from, int length, int transhdrlen, int hlimit,
+		    int tclass, struct ipv6_txoptions *opt, struct flowi6 *fl6,
+		    struct rt6_info *rt, unsigned int flags, int dontfrag);
+
+int ip6_push_pending_frames(struct sock *sk);
+
+void ip6_flush_pending_frames(struct sock *sk);
+
+int ip6_send_skb(struct sk_buff *skb);
+
+struct sk_buff *__ip6_make_skb(struct sock *sk, struct sk_buff_head *queue,
+			       struct inet_cork_full *cork,
+			       struct inet6_cork *v6_cork);
+struct sk_buff *ip6_make_skb(struct sock *sk,
+			     int getfrag(void *from, char *to, int offset,
+					 int len, int odd, struct sk_buff *skb),
+			     void *from, int length, int transhdrlen,
+			     int hlimit, int tclass, struct ipv6_txoptions *opt,
+			     struct flowi6 *fl6, struct rt6_info *rt,
+			     unsigned int flags, int dontfrag);
+
+static inline struct sk_buff *ip6_finish_skb(struct sock *sk)
+{
+	return __ip6_make_skb(sk, &sk->sk_write_queue, &inet_sk(sk)->cork,
+			      &inet6_sk(sk)->cork);
+}
+
+int ip6_dst_lookup(struct sock *sk, struct dst_entry **dst, struct flowi6 *fl6);
+struct dst_entry *ip6_dst_lookup_flow(struct sock *sk, struct flowi6 *fl6,
+				      const struct in6_addr *final_dst);
+struct dst_entry *ip6_sk_dst_lookup_flow(struct sock *sk, struct flowi6 *fl6,
+					 const struct in6_addr *final_dst);
+struct dst_entry *ip6_blackhole_route(struct net *net,
+				      struct dst_entry *orig_dst);
+
+/*
+ *	skb processing functions
+ */
+
+int ip6_output(struct sock *sk, struct sk_buff *skb);
+int ip6_forward(struct sk_buff *skb);
+int ip6_input(struct sk_buff *skb);
+int ip6_mc_input(struct sk_buff *skb);
+
+int __ip6_local_out(struct sk_buff *skb);
+int ip6_local_out_sk(struct sock *sk, struct sk_buff *skb);
+int ip6_local_out(struct sk_buff *skb);
+
+/*
+ *	Extension header (options) processing
+ */
+
+void ipv6_push_nfrag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt,
+			  u8 *proto, struct in6_addr **daddr_p);
+void ipv6_push_frag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt,
+			 u8 *proto);
+
+int ipv6_skip_exthdr(const struct sk_buff *, int start, u8 *nexthdrp,
+		     __be16 *frag_offp);
+
+bool ipv6_ext_hdr(u8 nexthdr);
+
+enum {
+	IP6_FH_F_FRAG		= (1 << 0),
+	IP6_FH_F_AUTH		= (1 << 1),
+	IP6_FH_F_SKIP_RH	= (1 << 2),
+};
+
+/* find specified header and get offset to it */
+int ipv6_find_hdr(const struct sk_buff *skb, unsigned int *offset, int target,
+		  unsigned short *fragoff, int *fragflg);
+
+int ipv6_find_tlv(struct sk_buff *skb, int offset, int type);
+
+struct in6_addr *fl6_update_dst(struct flowi6 *fl6,
+				const struct ipv6_txoptions *opt,
+				struct in6_addr *orig);
+
+/*
+ *	socket options (ipv6_sockglue.c)
+ */
+
+int ipv6_setsockopt(struct sock *sk, int level, int optname,
+		    char __user *optval, unsigned int optlen);
+int ipv6_getsockopt(struct sock *sk, int level, int optname,
+		    char __user *optval, int __user *optlen);
+int compat_ipv6_setsockopt(struct sock *sk, int level, int optname,
+			   char __user *optval, unsigned int optlen);
+int compat_ipv6_getsockopt(struct sock *sk, int level, int optname,
+			   char __user *optval, int __user *optlen);
+
+int ip6_datagram_connect(struct sock *sk, struct sockaddr *addr, int addr_len);
+int ip6_datagram_connect_v6_only(struct sock *sk, struct sockaddr *addr,
+				 int addr_len);
+
+int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len,
+		    int *addr_len);
+int ipv6_recv_rxpmtu(struct sock *sk, struct msghdr *msg, int len,
+		     int *addr_len);
+void ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err, __be16 port,
+		     u32 info, u8 *payload);
+void ipv6_local_error(struct sock *sk, int err, struct flowi6 *fl6, u32 info);
+void ipv6_local_rxpmtu(struct sock *sk, struct flowi6 *fl6, u32 mtu);
+
+int inet6_release(struct socket *sock);
+int inet6_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len);
+int inet6_getname(struct socket *sock, struct sockaddr *uaddr, int *uaddr_len,
+		  int peer);
+int inet6_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg);
+
+int inet6_hash_connect(struct inet_timewait_death_row *death_row,
+			      struct sock *sk);
+
+/*
+ * reassembly.c
+ */
+extern const struct proto_ops inet6_stream_ops;
+extern const struct proto_ops inet6_dgram_ops;
+
+struct group_source_req;
+struct group_filter;
+
+int ip6_mc_source(int add, int omode, struct sock *sk,
+		  struct group_source_req *pgsr);
+int ip6_mc_msfilter(struct sock *sk, struct group_filter *gsf);
+int ip6_mc_msfget(struct sock *sk, struct group_filter *gsf,
+		  struct group_filter __user *optval, int __user *optlen);
+
+#ifdef CONFIG_PROC_FS
+int ac6_proc_init(struct net *net);
+void ac6_proc_exit(struct net *net);
+int raw6_proc_init(void);
+void raw6_proc_exit(void);
+int tcp6_proc_init(struct net *net);
+void tcp6_proc_exit(struct net *net);
+int udp6_proc_init(struct net *net);
+void udp6_proc_exit(struct net *net);
+int udplite6_proc_init(void);
+void udplite6_proc_exit(void);
+int ipv6_misc_proc_init(void);
+void ipv6_misc_proc_exit(void);
+int snmp6_register_dev(struct inet6_dev *idev);
+int snmp6_unregister_dev(struct inet6_dev *idev);
+
+#else
+static inline int ac6_proc_init(struct net *net) { return 0; }
+static inline void ac6_proc_exit(struct net *net) { }
+static inline int snmp6_register_dev(struct inet6_dev *idev) { return 0; }
+static inline int snmp6_unregister_dev(struct inet6_dev *idev) { return 0; }
+#endif
+
+#ifdef CONFIG_SYSCTL
+extern struct ctl_table ipv6_route_table_template[];
+
+struct ctl_table *ipv6_icmp_sysctl_init(struct net *net);
+struct ctl_table *ipv6_route_sysctl_init(struct net *net);
+int ipv6_sysctl_register(void);
+void ipv6_sysctl_unregister(void);
+#endif
+
+int ipv6_sock_mc_join(struct sock *sk, int ifindex,
+		      const struct in6_addr *addr);
+int ipv6_sock_mc_drop(struct sock *sk, int ifindex,
+		      const struct in6_addr *addr);
+#endif /* _NET_IPV6_H */