#ifndef _IPV6_H
#define _IPV6_H

#include <linux/config.h>
#include <linux/in6.h>
#include <asm/byteorder.h>

/* The latest drafts declared increase in minimal mtu up to 1280. */

#define IPV6_MIN_MTU    1280

/*
 *      Advanced API
 *      source interface/address selection, source routing, etc...
 *      *under construction*
 */


struct in6_pktinfo {
        struct in6_addr ipi6_addr;
        int             ipi6_ifindex;
};


struct in6_ifreq {
        struct in6_addr ifr6_addr;
        __u32           ifr6_prefixlen;
        int             ifr6_ifindex; 
};

#define IPV6_SRCRT_STRICT       0x01    /* this hop must be a neighbor  */
#define IPV6_SRCRT_TYPE_0       0       /* IPv6 type 0 Routing Header   */

/*
 *      routing header
 */
struct ipv6_rt_hdr {
        __u8            nexthdr;
        __u8            hdrlen;
        __u8            type;
        __u8            segments_left;

        /*
         *      type specific data
         *      variable length field
         */
};


struct ipv6_opt_hdr {
        __u8            nexthdr;
        __u8            hdrlen;
        /* 
         * TLV encoded option data follows.
         */
};

#define ipv6_destopt_hdr ipv6_opt_hdr
#define ipv6_hopopt_hdr  ipv6_opt_hdr

#ifdef __KERNEL__
#define ipv6_optlen(p)  (((p)->hdrlen+1) << 3)
#endif

/*
 *      routing header type 0 (used in cmsghdr struct)
 */

struct rt0_hdr {
        struct ipv6_rt_hdr      rt_hdr;
        __u32                   bitmap;         /* strict/loose bit map */
        struct in6_addr         addr[0];

#define rt0_type                rt_hdr.type
};

struct ipv6_auth_hdr {
        __u8  nexthdr;
        __u8  hdrlen;           /* This one is measured in 32 bit units! */
        __u16 reserved;
        __u32 spi;
        __u32 seq_no;           /* Sequence number */
        __u8  auth_data[0];     /* Length variable but >=4. Mind the 64 bit alignment! */
};

struct ipv6_esp_hdr {
        __u32 spi;
        __u32 seq_no;           /* Sequence number */
        __u8  enc_data[0];      /* Length variable but >=8. Mind the 64 bit alignment! */
};

struct ipv6_comp_hdr {
        __u8 nexthdr;
        __u8 flags;
        __u16 cpi;
};

/*
 *      IPv6 fixed header
 *
 *      BEWARE, it is incorrect. The first 4 bits of flow_lbl
 *      are glued to priority now, forming "class".
 */

struct ipv6hdr {
#if defined(__LITTLE_ENDIAN_BITFIELD)
        __u8                    priority:4,
                                version:4;
#elif defined(__BIG_ENDIAN_BITFIELD)
        __u8                    version:4,
                                priority:4;
#else
#error  "Please fix <asm/byteorder.h>"
#endif
        __u8                    flow_lbl[3];

        __u16                   payload_len;
        __u8                    nexthdr;
        __u8                    hop_limit;

        struct  in6_addr        saddr;
        struct  in6_addr        daddr;
};

/*
 * 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;
#ifdef CONFIG_IPV6_PRIVACY
        __s32           use_tempaddr;
        __s32           temp_valid_lft;
        __s32           temp_prefered_lft;
        __s32           regen_max_retry;
        __s32           max_desync_factor;
#endif
        __s32           max_addresses;
        void            *sysctl;
};

/* index values for the variables in ipv6_devconf */
enum {
        DEVCONF_FORWARDING = 0,
        DEVCONF_HOPLIMIT,
        DEVCONF_MTU6,
        DEVCONF_ACCEPT_RA,
        DEVCONF_ACCEPT_REDIRECTS,
        DEVCONF_AUTOCONF,
        DEVCONF_DAD_TRANSMITS,
        DEVCONF_RTR_SOLICITS,
        DEVCONF_RTR_SOLICIT_INTERVAL,
        DEVCONF_RTR_SOLICIT_DELAY,
        DEVCONF_USE_TEMPADDR,
        DEVCONF_TEMP_VALID_LFT,
        DEVCONF_TEMP_PREFERED_LFT,
        DEVCONF_REGEN_MAX_RETRY,
        DEVCONF_MAX_DESYNC_FACTOR,
        DEVCONF_MAX_ADDRESSES,
        DEVCONF_FORCE_MLD_VERSION,
        DEVCONF_MAX
};

#ifdef __KERNEL__
#include <linux/in6.h>          /* struct sockaddr_in6 */
#include <linux/icmpv6.h>
#include <net/if_inet6.h>       /* struct ipv6_mc_socklist */
#include <linux/tcp.h>
#include <linux/udp.h>

/* 
   This structure contains results of exthdrs parsing
   as offsets from skb->nh.
 */

struct inet6_skb_parm
{
        int                     iif;
        __u16                   ra;
        __u16                   hop;
        __u16                   dst0;
        __u16                   srcrt;
        __u16                   dst1;
};

#define IP6CB(skb)      ((struct inet6_skb_parm*)((skb)->cb))

struct ipv6_pinfo {
        struct in6_addr         saddr;
        struct in6_addr         rcv_saddr;
        struct in6_addr         daddr;
        struct in6_addr         *daddr_cache;

        __u32                   flow_label;
        __u32                   frag_size;
        int                     hop_limit;
        int                     mcast_hops;
        int                     mcast_oif;

        /* pktoption flags */
        union {
                struct {
                        __u8    srcrt:2,
                                rxinfo:1,
                                rxhlim:1,
                                hopopts:1,
                                dstopts:1,
                                rxflow:1;
                } bits;
                __u8            all;
        } rxopt;

        /* sockopt flags */
        __u8                    mc_loop:1,
                                recverr:1,
                                sndflow:1,
                                pmtudisc:2,
                                ipv6only:1;

        struct ipv6_mc_socklist *ipv6_mc_list;
        struct ipv6_ac_socklist *ipv6_ac_list;
        struct ipv6_fl_socklist *ipv6_fl_list;
        __u32                   dst_cookie;

        struct ipv6_txoptions   *opt;
        struct sk_buff          *pktoptions;
        struct {
                struct ipv6_txoptions *opt;
                struct rt6_info *rt;
                int hop_limit;
        } cork;
};

struct raw6_opt {
        __u32                   checksum;       /* perform checksum */
        __u32                   offset;         /* checksum offset  */

        struct icmp6_filter     filter;
};

/* WARNING: don't change the layout of the members in {raw,udp,tcp}6_sock! */
struct raw6_sock {
        struct sock       sk;
        struct ipv6_pinfo *pinet6;
        struct inet_opt   inet;
        struct raw6_opt   raw6;
        struct ipv6_pinfo inet6;
};

struct udp6_sock {
        struct sock       sk;
        struct ipv6_pinfo *pinet6;
        struct inet_opt   inet;
        struct udp_opt    udp;
        struct ipv6_pinfo inet6;
};

struct tcp6_sock {
        struct sock       sk;
        struct ipv6_pinfo *pinet6;
        struct inet_opt   inet;
        struct tcp_opt    tcp;
        struct ipv6_pinfo inet6;
};

static inline struct ipv6_pinfo * inet6_sk(const struct sock *__sk)
{
        return ((struct raw6_sock *)__sk)->pinet6;
}

static inline struct raw6_opt * raw6_sk(const struct sock *__sk)
{
        return &((struct raw6_sock *)__sk)->raw6;
}

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
#define __ipv6_only_sock(sk)    (inet6_sk(sk)->ipv6only)
#define ipv6_only_sock(sk)      ((sk)->sk_family == PF_INET6 && __ipv6_only_sock(sk))
#else
#define __ipv6_only_sock(sk)    0
#define ipv6_only_sock(sk)      0
#endif

#endif

#endif