/***************************************************************************
 * IPv6Header.h -- The IPv6Header Class represents an IPv6 datagram. It    *
 * contains methods to set any header field. In general, these methods do  *
 * error checkings and byte order conversion.                              *
 *                                                                         *
 ***********************IMPORTANT NMAP LICENSE TERMS************************
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 ***************************************************************************/
/* This code was originally part of the Nping tool.                        */

#ifndef IPV6HEADER_H
#define IPV6HEADER_H 1

#include "NetworkLayerElement.h"

#define IPv6_HEADER_LEN 40

/* Default header values */
#define IPv6_DEFAULT_TCLASS    0
#define IPv6_DEFAULT_FLABEL    0
#define IPv6_DEFAULT_HOPLIM    64
#define IPv6_DEFAULT_NXTHDR    6 /* TCP */

class IPv6Header : public NetworkLayerElement {

    private:

  /*  IPv6 Header Format:
        0                   1                   2                   3
        0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2
        +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
        |Version| Traffic Class |             Flow Label                |
        +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
        |         Payload Length        |  Next Header  |   Hop Limit   |
        +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
        |                                                               |
        +--                                                           --+
        |                                                               |
        +--                      Source Address                       --+
        |                                                               |
        +--                                                           --+
        |                                                               |
        +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
        |                                                               |
        +--                                                           --+
        |                                                               |
        +--                    Destination Address                    --+
        |                                                               |
        +--                                                           --+
        |                                                               |
        +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    */

        struct nping_ipv6_hdr {
            u8  ip6_start[4];                /* Version, Traffic and Flow   */
            u16 ip6_len;                     /* Payload length              */
            u8  ip6_nh;                      /* Next Header                 */
            u8  ip6_hopl;                    /* Hop Limit                   */
            u8  ip6_src[16];                 /* Source IP Address           */
            u8  ip6_dst[16];                 /* Destination IP Address      */
        }__attribute__((__packed__));

        typedef struct nping_ipv6_hdr nping_ipv6_hdr_t;

        nping_ipv6_hdr_t h;

    public:

        /* Misc */
        IPv6Header();
        ~IPv6Header();
        void reset();
        u8 *getBufferPointer();
        int storeRecvData(const u8 *buf, size_t len);
        int protocol_id() const;
        int validate();
        int print(FILE *output, int detail) const;

        /* IP version */
        int setVersion();
        int setVersion(u8 val);
        u8 getVersion() const;

        /* Traffic class */
        int setTrafficClass(u8 val);
        u8 getTrafficClass() const;

        /* Flow Label */
        int setFlowLabel(u32 val);
        u32 getFlowLabel() const;

        /* Payload Length */
        int setPayloadLength(u16 val);
        int setPayloadLength();
        u16 getPayloadLength() const;

        /* Next Header */
        int setNextHeader(u8 val);
        int setNextHeader(const char *p);
        u8 getNextHeader() const;

        /* Hop Limit */
        int setHopLimit(u8 val);
        u8 getHopLimit() const;

        /* Source Address */
        int setSourceAddress(u8 *val);
        int setSourceAddress(struct in6_addr val);
        const u8 *getSourceAddress() const;
        struct in6_addr getSourceAddress(struct in6_addr *result) const;

        /* Destination Address*/
        int setDestinationAddress(u8 *val);
        int setDestinationAddress(struct in6_addr val);
        const u8 *getDestinationAddress() const;
        struct in6_addr getDestinationAddress(struct in6_addr *result) const;

        u16 getAddressLength() const;
};

#endif
