File-copy from v4.4.100

This is the result of 'cp' from a linux-stable tree with the 'v4.4.100'
tag checked out (commit 26d6298789e695c9f627ce49a7bbd2286405798a) on
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git

Please refer to that tree for all history prior to this point.

Change-Id: I8a9ee2aea93cd29c52c847d0ce33091a73ae6afe
diff --git a/include/linux/ipv6.h b/include/linux/ipv6.h
new file mode 100644
index 0000000..402753b
--- /dev/null
+++ b/include/linux/ipv6.h
@@ -0,0 +1,330 @@
+#ifndef _IPV6_H
+#define _IPV6_H
+
+#include <uapi/linux/ipv6.h>
+
+#define ipv6_optlen(p)  (((p)->hdrlen+1) << 3)
+#define ipv6_authlen(p) (((p)->hdrlen+2) << 2)
+/*
+ * This structure contains configuration options per IPv6 link.
+ */
+struct ipv6_devconf {
+	__s32		forwarding;
+	__s32		hop_limit;
+	__s32		mtu6;
+	__s32		accept_ra;
+	__s32		accept_redirects;
+	__s32		autoconf;
+	__s32		dad_transmits;
+	__s32		rtr_solicits;
+	__s32		rtr_solicit_interval;
+	__s32		rtr_solicit_delay;
+	__s32		force_mld_version;
+	__s32		mldv1_unsolicited_report_interval;
+	__s32		mldv2_unsolicited_report_interval;
+	__s32		use_tempaddr;
+	__s32		temp_valid_lft;
+	__s32		temp_prefered_lft;
+	__s32		regen_max_retry;
+	__s32		max_desync_factor;
+	__s32		max_addresses;
+	__s32		accept_ra_defrtr;
+	__s32		accept_ra_min_hop_limit;
+	__s32		accept_ra_pinfo;
+	__s32		ignore_routes_with_linkdown;
+#ifdef CONFIG_IPV6_ROUTER_PREF
+	__s32		accept_ra_rtr_pref;
+	__s32		rtr_probe_interval;
+#ifdef CONFIG_IPV6_ROUTE_INFO
+	__s32		accept_ra_rt_info_max_plen;
+#endif
+#endif
+	__s32		proxy_ndp;
+	__s32		accept_source_route;
+	__s32		accept_ra_from_local;
+#ifdef CONFIG_IPV6_OPTIMISTIC_DAD
+	__s32		optimistic_dad;
+	__s32		use_optimistic;
+#endif
+#ifdef CONFIG_IPV6_MROUTE
+	__s32		mc_forwarding;
+#endif
+	__s32		disable_ipv6;
+	__s32		accept_dad;
+	__s32		force_tllao;
+	__s32           ndisc_notify;
+	__s32		suppress_frag_ndisc;
+	__s32		accept_ra_mtu;
+	struct ipv6_stable_secret {
+		bool initialized;
+		struct in6_addr secret;
+	} stable_secret;
+	__s32		use_oif_addrs_only;
+	void		*sysctl;
+};
+
+struct ipv6_params {
+	__s32 disable_ipv6;
+	__s32 autoconf;
+};
+extern struct ipv6_params ipv6_defaults;
+#include <linux/icmpv6.h>
+#include <linux/tcp.h>
+#include <linux/udp.h>
+
+#include <net/inet_sock.h>
+
+static inline struct ipv6hdr *ipv6_hdr(const struct sk_buff *skb)
+{
+	return (struct ipv6hdr *)skb_network_header(skb);
+}
+
+static inline struct ipv6hdr *inner_ipv6_hdr(const struct sk_buff *skb)
+{
+	return (struct ipv6hdr *)skb_inner_network_header(skb);
+}
+
+static inline struct ipv6hdr *ipipv6_hdr(const struct sk_buff *skb)
+{
+	return (struct ipv6hdr *)skb_transport_header(skb);
+}
+
+/* 
+   This structure contains results of exthdrs parsing
+   as offsets from skb->nh.
+ */
+
+struct inet6_skb_parm {
+	int			iif;
+	__be16			ra;
+	__u16			dst0;
+	__u16			srcrt;
+	__u16			dst1;
+	__u16			lastopt;
+	__u16			nhoff;
+	__u16			flags;
+#if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
+	__u16			dsthao;
+#endif
+	__u16			frag_max_size;
+
+#define IP6SKB_XFRM_TRANSFORMED	1
+#define IP6SKB_FORWARDED	2
+#define IP6SKB_REROUTED		4
+#define IP6SKB_ROUTERALERT	8
+#define IP6SKB_FRAGMENTED      16
+#define IP6SKB_HOPBYHOP        32
+};
+
+#define IP6CB(skb)	((struct inet6_skb_parm*)((skb)->cb))
+#define IP6CBMTU(skb)	((struct ip6_mtuinfo *)((skb)->cb))
+
+static inline int inet6_iif(const struct sk_buff *skb)
+{
+	return IP6CB(skb)->iif;
+}
+
+struct tcp6_request_sock {
+	struct tcp_request_sock	  tcp6rsk_tcp;
+};
+
+struct ipv6_mc_socklist;
+struct ipv6_ac_socklist;
+struct ipv6_fl_socklist;
+
+struct inet6_cork {
+	struct ipv6_txoptions *opt;
+	u8 hop_limit;
+	u8 tclass;
+};
+
+/**
+ * struct ipv6_pinfo - ipv6 private area
+ *
+ * In the struct sock hierarchy (tcp6_sock, upd6_sock, etc)
+ * this _must_ be the last member, so that inet6_sk_generic
+ * is able to calculate its offset from the base struct sock
+ * by using the struct proto->slab_obj_size member. -acme
+ */
+struct ipv6_pinfo {
+	struct in6_addr 	saddr;
+	struct in6_pktinfo	sticky_pktinfo;
+	const struct in6_addr		*daddr_cache;
+#ifdef CONFIG_IPV6_SUBTREES
+	const struct in6_addr		*saddr_cache;
+#endif
+
+	__be32			flow_label;
+	__u32			frag_size;
+
+	/*
+	 * Packed in 16bits.
+	 * Omit one shift by by putting the signed field at MSB.
+	 */
+#if defined(__BIG_ENDIAN_BITFIELD)
+	__s16			hop_limit:9;
+	__u16			__unused_1:7;
+#else
+	__u16			__unused_1:7;
+	__s16			hop_limit:9;
+#endif
+
+#if defined(__BIG_ENDIAN_BITFIELD)
+	/* Packed in 16bits. */
+	__s16			mcast_hops:9;
+	__u16			__unused_2:6,
+				mc_loop:1;
+#else
+	__u16			mc_loop:1,
+				__unused_2:6;
+	__s16			mcast_hops:9;
+#endif
+	int			ucast_oif;
+	int			mcast_oif;
+
+	/* pktoption flags */
+	union {
+		struct {
+			__u16	srcrt:1,
+				osrcrt:1,
+			        rxinfo:1,
+			        rxoinfo:1,
+				rxhlim:1,
+				rxohlim:1,
+				hopopts:1,
+				ohopopts:1,
+				dstopts:1,
+				odstopts:1,
+                                rxflow:1,
+				rxtclass:1,
+				rxpmtu:1,
+				rxorigdstaddr:1;
+				/* 2 bits hole */
+		} bits;
+		__u16		all;
+	} rxopt;
+
+	/* sockopt flags */
+	__u16			recverr:1,
+	                        sndflow:1,
+				repflow:1,
+				pmtudisc:3,
+				padding:1,	/* 1 bit hole */
+				srcprefs:3,	/* 001: prefer temporary address
+						 * 010: prefer public address
+						 * 100: prefer care-of address
+						 */
+				dontfrag:1,
+				autoflowlabel:1;
+	__u8			min_hopcount;
+	__u8			tclass;
+	__be32			rcv_flowinfo;
+
+	__u32			dst_cookie;
+	__u32			rx_dst_cookie;
+
+	struct ipv6_mc_socklist	__rcu *ipv6_mc_list;
+	struct ipv6_ac_socklist	*ipv6_ac_list;
+	struct ipv6_fl_socklist __rcu *ipv6_fl_list;
+
+	struct ipv6_txoptions __rcu	*opt;
+	struct sk_buff		*pktoptions;
+	struct sk_buff		*rxpmtu;
+	struct inet6_cork	cork;
+};
+
+/* WARNING: don't change the layout of the members in {raw,udp,tcp}6_sock! */
+struct raw6_sock {
+	/* inet_sock has to be the first member of raw6_sock */
+	struct inet_sock	inet;
+	__u32			checksum;	/* perform checksum */
+	__u32			offset;		/* checksum offset  */
+	struct icmp6_filter	filter;
+	__u32			ip6mr_table;
+	/* ipv6_pinfo has to be the last member of raw6_sock, see inet6_sk_generic */
+	struct ipv6_pinfo	inet6;
+};
+
+struct udp6_sock {
+	struct udp_sock	  udp;
+	/* ipv6_pinfo has to be the last member of udp6_sock, see inet6_sk_generic */
+	struct ipv6_pinfo inet6;
+};
+
+struct tcp6_sock {
+	struct tcp_sock	  tcp;
+	/* ipv6_pinfo has to be the last member of tcp6_sock, see inet6_sk_generic */
+	struct ipv6_pinfo inet6;
+};
+
+extern int inet6_sk_rebuild_header(struct sock *sk);
+
+struct tcp6_timewait_sock {
+	struct tcp_timewait_sock   tcp6tw_tcp;
+};
+
+#if IS_ENABLED(CONFIG_IPV6)
+static inline struct ipv6_pinfo *inet6_sk(const struct sock *__sk)
+{
+	return sk_fullsock(__sk) ? inet_sk(__sk)->pinet6 : NULL;
+}
+
+static inline struct raw6_sock *raw6_sk(const struct sock *sk)
+{
+	return (struct raw6_sock *)sk;
+}
+
+static inline void inet_sk_copy_descendant(struct sock *sk_to,
+					   const struct sock *sk_from)
+{
+	int ancestor_size = sizeof(struct inet_sock);
+
+	if (sk_from->sk_family == PF_INET6)
+		ancestor_size += sizeof(struct ipv6_pinfo);
+
+	__inet_sk_copy_descendant(sk_to, sk_from, ancestor_size);
+}
+
+#define __ipv6_only_sock(sk)	(sk->sk_ipv6only)
+#define ipv6_only_sock(sk)	(__ipv6_only_sock(sk))
+#define ipv6_sk_rxinfo(sk)	((sk)->sk_family == PF_INET6 && \
+				 inet6_sk(sk)->rxopt.bits.rxinfo)
+
+static inline const struct in6_addr *inet6_rcv_saddr(const struct sock *sk)
+{
+	if (sk->sk_family == AF_INET6)
+		return &sk->sk_v6_rcv_saddr;
+	return NULL;
+}
+
+static inline int inet_v6_ipv6only(const struct sock *sk)
+{
+	/* ipv6only field is at same position for timewait and other sockets */
+	return ipv6_only_sock(sk);
+}
+#else
+#define __ipv6_only_sock(sk)	0
+#define ipv6_only_sock(sk)	0
+#define ipv6_sk_rxinfo(sk)	0
+
+static inline struct ipv6_pinfo * inet6_sk(const struct sock *__sk)
+{
+	return NULL;
+}
+
+static inline struct inet6_request_sock *
+			inet6_rsk(const struct request_sock *rsk)
+{
+	return NULL;
+}
+
+static inline struct raw6_sock *raw6_sk(const struct sock *sk)
+{
+	return NULL;
+}
+
+#define inet6_rcv_saddr(__sk)	NULL
+#define tcp_twsk_ipv6only(__sk)		0
+#define inet_v6_ipv6only(__sk)		0
+#endif /* IS_ENABLED(CONFIG_IPV6) */
+#endif /* _IPV6_H */