/*
   *	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 <net/if_inet6.h>

  #include <net/ndisc.h>
  #include <net/flow.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_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_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

  #include <net/sock.h>
  
  /* sysctls */

  extern int sysctl_mld_max_msf;

  extern struct ctl_path net_ipv6_ctl_path[];

  #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));\
  })

  #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)		\

  	_DEVINCATOMIC(net, icmpv6msg, , idev, field +256)

  #define ICMP6MSGOUT_INC_STATS_BH(net, idev, field)	\

  	_DEVINCATOMIC(net, icmpv6msg, _BH, idev, field +256)

  #define ICMP6MSGIN_INC_STATS_BH(net, idev, field)	\

  	_DEVINCATOMIC(net, icmpv6msg, _BH, 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	*next;

  	__be32			label;

  	atomic_t		users;

  	struct in6_addr		dst;
  	struct ipv6_txoptions	*opt;

  	unsigned long		linger;
  	u8			share;
  	u32			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)

  struct ipv6_fl_socklist {

  	struct ipv6_fl_socklist	*next;
  	struct ip6_flowlabel	*fl;
  };

  extern struct ip6_flowlabel	*fl6_sock_lookup(struct sock *sk, __be32 label);

  extern struct ipv6_txoptions	*fl6_merge_options(struct ipv6_txoptions * opt_space,
  						   struct ip6_flowlabel * fl,
  						   struct ipv6_txoptions * fopt);
  extern void			fl6_free_socklist(struct sock *sk);
  extern int			ipv6_flowlabel_opt(struct sock *sk, char __user *optval, int optlen);

  extern int			ip6_flowlabel_init(void);

  extern void			ip6_flowlabel_cleanup(void);
  
  static inline void fl6_sock_release(struct ip6_flowlabel *fl)
  {
  	if (fl)
  		atomic_dec(&fl->users);
  }

  extern int 			ip6_ra_control(struct sock *sk, int sel);

  extern int			ipv6_parse_hopopts(struct sk_buff *skb);

  
  extern struct ipv6_txoptions *  ipv6_dup_options(struct sock *sk, struct ipv6_txoptions *opt);

  extern 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);

  extern int ipv6_opt_accepted(struct sock *sk, struct sk_buff *skb);

  int ip6_frag_nqueues(struct net *net);

  int ip6_frag_mem(struct net *net);

  #define IPV6_FRAG_HIGH_THRESH	(256 * 1024)	/* 262144 */
  #define IPV6_FRAG_LOW_THRESH	(192 * 1024)	/* 196608 */
  #define IPV6_FRAG_TIMEOUT	(60 * HZ)	/* 60 seconds */

  extern 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 int ipv6_addr_cmp(const struct in6_addr *a1, const struct in6_addr *a2)
  {

  	return memcmp(a1, a2, sizeof(struct in6_addr));

  }

  static inline int
  ipv6_masked_addr_cmp(const struct in6_addr *a1, const struct in6_addr *m,
  		     const struct in6_addr *a2)
  {

  	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]));

  }

  static inline void ipv6_addr_copy(struct in6_addr *a1, const struct in6_addr *a2)
  {

  	memcpy(a1, a2, sizeof(struct in6_addr));

  }
  
  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(struct in6_addr *addr, 

  				     __be32 w1, __be32 w2,
  				     __be32 w3, __be32 w4)

  {
  	addr->s6_addr32[0] = w1;
  	addr->s6_addr32[1] = w2;
  	addr->s6_addr32[2] = w3;
  	addr->s6_addr32[3] = w4;
  }

  
  static inline int ipv6_addr_equal(const struct in6_addr *a1,
  				  const struct in6_addr *a2)
  {

  	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;

  }

  static inline int __ipv6_prefix_equal(const __be32 *a1, const __be32 *a2,

  				      unsigned int prefixlen)
  {
  	unsigned pdw, pbi;
  
  	/* check complete u32 in prefix */
  	pdw = prefixlen >> 5;
  	if (pdw && memcmp(a1, a2, pdw << 2))
  		return 0;
  
  	/* check incomplete u32 in prefix */
  	pbi = prefixlen & 0x1f;
  	if (pbi && ((a1[pdw] ^ a2[pdw]) & htonl((0xffffffff) << (32 - pbi))))
  		return 0;
  
  	return 1;
  }
  
  static inline int ipv6_prefix_equal(const struct in6_addr *a1,
  				    const struct in6_addr *a2,
  				    unsigned int prefixlen)
  {
  	return __ipv6_prefix_equal(a1->s6_addr32, a2->s6_addr32,
  				   prefixlen);
  }

  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;

  };
  
  void ip6_frag_init(struct inet_frag_queue *q, void *a);

  int ip6_frag_match(struct inet_frag_queue *q, void *a);

  static inline int ipv6_addr_any(const struct in6_addr *a)
  {

  	return (a->s6_addr32[0] | a->s6_addr32[1] |
  		a->s6_addr32[2] | a->s6_addr32[3]) == 0;

  }

  static inline int ipv6_addr_loopback(const struct in6_addr *a)
  {

  	return (a->s6_addr32[0] | a->s6_addr32[1] |
  		a->s6_addr32[2] | (a->s6_addr32[3] ^ htonl(1))) == 0;

  }

  static inline int ipv6_addr_v4mapped(const struct in6_addr *a)
  {

  	return (a->s6_addr32[0] | a->s6_addr32[1] |
  		 (a->s6_addr32[2] ^ htonl(0x0000ffff))) == 0;

  }

  /*

   * Check for a RFC 4843 ORCHID address
   * (Overlay Routable Cryptographic Hash Identifiers)
   */
  static inline int ipv6_addr_orchid(const struct in6_addr *a)
  {

  	return (a->s6_addr32[0] & htonl(0xfffffff0)) == htonl(0x20010010);

  }

  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_diff(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;

  }
  
  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));
  }

  extern void ipv6_select_ident(struct frag_hdr *fhdr, struct rt6_info *rt);

  /*

   *	Prototypes exported by ipv6
   */
  
  /*
   *	rcv function (called from netdevice level)
   */
  
  extern int			ipv6_rcv(struct sk_buff *skb, 
  					 struct net_device *dev, 

  					 struct packet_type *pt,
  					 struct net_device *orig_dev);

  extern int			ip6_rcv_finish(struct sk_buff *skb);

  /*
   *	upper-layer output functions
   */
  extern int			ip6_xmit(struct sock *sk,
  					 struct sk_buff *skb,

  					 struct flowi6 *fl6,

  					 struct ipv6_txoptions *opt,
  					 int tclass);

  
  extern int			ip6_nd_hdr(struct sock *sk,
  					   struct sk_buff *skb,
  					   struct net_device *dev,

  					   const struct in6_addr *saddr,
  					   const struct in6_addr *daddr,

  					   int proto, int len);
  
  extern int			ip6_find_1stfragopt(struct sk_buff *skb, u8 **nexthdr);
  
  extern 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);

  
  extern int			ip6_push_pending_frames(struct sock *sk);
  
  extern void			ip6_flush_pending_frames(struct sock *sk);
  
  extern int			ip6_dst_lookup(struct sock *sk,
  					       struct dst_entry **dst,

  					       struct flowi6 *fl6);

  extern struct dst_entry *	ip6_dst_lookup_flow(struct sock *sk,

  						    struct flowi6 *fl6,

  						    const struct in6_addr *final_dst,

  						    bool can_sleep);

  extern struct dst_entry *	ip6_sk_dst_lookup_flow(struct sock *sk,

  						       struct flowi6 *fl6,

  						       const struct in6_addr *final_dst,

  						       bool can_sleep);

  extern struct dst_entry *	ip6_blackhole_route(struct net *net,
  						    struct dst_entry *orig_dst);

  
  /*
   *	skb processing functions
   */
  
  extern int			ip6_output(struct sk_buff *skb);
  extern int			ip6_forward(struct sk_buff *skb);
  extern int			ip6_input(struct sk_buff *skb);
  extern int			ip6_mc_input(struct sk_buff *skb);

  extern int			__ip6_local_out(struct sk_buff *skb);
  extern int			ip6_local_out(struct sk_buff *skb);

  /*
   *	Extension header (options) processing
   */

  extern void 			ipv6_push_nfrag_opts(struct sk_buff *skb,
  						     struct ipv6_txoptions *opt,
  						     u8 *proto,
  						     struct in6_addr **daddr_p);
  extern void			ipv6_push_frag_opts(struct sk_buff *skb,
  						    struct ipv6_txoptions *opt,
  						    u8 *proto);
  
  extern int			ipv6_skip_exthdr(const struct sk_buff *, int start,

  					         u8 *nexthdrp);

  
  extern int 			ipv6_ext_hdr(u8 nexthdr);

  extern int ipv6_find_tlv(struct sk_buff *skb, int offset, int type);

  extern struct in6_addr *fl6_update_dst(struct flowi6 *fl6,

  				       const struct ipv6_txoptions *opt,
  				       struct in6_addr *orig);

  /*
   *	socket options (ipv6_sockglue.c)
   */
  
  extern int			ipv6_setsockopt(struct sock *sk, int level, 
  						int optname,
  						char __user *optval, 

  						unsigned int optlen);

  extern int			ipv6_getsockopt(struct sock *sk, int level, 
  						int optname,
  						char __user *optval, 
  						int __user *optlen);

  extern int			compat_ipv6_setsockopt(struct sock *sk,
  						int level,
  						int optname,
  						char __user *optval,

  						unsigned int optlen);

  extern int			compat_ipv6_getsockopt(struct sock *sk,
  						int level,
  						int optname,
  						char __user *optval,
  						int __user *optlen);

  extern int			ip6_datagram_connect(struct sock *sk, 
  						     struct sockaddr *addr, int addr_len);
  
  extern int 			ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len);

  extern int 			ipv6_recv_rxpmtu(struct sock *sk, struct msghdr *msg, int len);

  extern void			ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err, __be16 port,

  						u32 info, u8 *payload);

  extern void			ipv6_local_error(struct sock *sk, int err, struct flowi6 *fl6, u32 info);
  extern void			ipv6_local_rxpmtu(struct sock *sk, struct flowi6 *fl6, u32 mtu);

  
  extern int inet6_release(struct socket *sock);
  extern int inet6_bind(struct socket *sock, struct sockaddr *uaddr, 
  		      int addr_len);
  extern int inet6_getname(struct socket *sock, struct sockaddr *uaddr,
  			 int *uaddr_len, int peer);
  extern int inet6_ioctl(struct socket *sock, unsigned int cmd, 
  		       unsigned long arg);

  extern 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;

  extern int ip6_mc_source(int add, int omode, struct sock *sk,
  			 struct group_source_req *pgsr);
  extern int ip6_mc_msfilter(struct sock *sk, struct group_filter *gsf);
  extern int ip6_mc_msfget(struct sock *sk, struct group_filter *gsf,
  			 struct group_filter __user *optval,
  			 int __user *optlen);

  extern unsigned int inet6_hash_frag(__be32 id, const struct in6_addr *saddr,
  				    const struct in6_addr *daddr, u32 rnd);

  
  #ifdef CONFIG_PROC_FS

  extern int  ac6_proc_init(struct net *net);
  extern void ac6_proc_exit(struct net *net);

  extern int  raw6_proc_init(void);
  extern void raw6_proc_exit(void);

  extern int  tcp6_proc_init(struct net *net);
  extern void tcp6_proc_exit(struct net *net);

  extern int  udp6_proc_init(struct net *net);
  extern void udp6_proc_exit(struct net *net);

  extern int  udplite6_proc_init(void);
  extern void udplite6_proc_exit(void);

  extern int  ipv6_misc_proc_init(void);
  extern void ipv6_misc_proc_exit(void);

  extern int snmp6_register_dev(struct inet6_dev *idev);
  extern 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 ctl_table ipv6_route_table_template[];
  extern ctl_table ipv6_icmp_table_template[];

  extern struct ctl_table *ipv6_icmp_sysctl_init(struct net *net);
  extern struct ctl_table *ipv6_route_sysctl_init(struct net *net);

  extern int ipv6_sysctl_register(void);

  extern void ipv6_sysctl_unregister(void);

  extern int ipv6_static_sysctl_register(void);
  extern void ipv6_static_sysctl_unregister(void);

  #endif

  #endif /* _NET_IPV6_H */