/***************************************************************************
 * HopByHopHeader.h -- The HopByHopHeader Class represents an IPv6         *
 * Hop-by-Hop extension header.                                            *
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/* This code was originally part of the Nping tool.                        */

#ifndef __HOP_BY_HOP_HEADER_H__
#define __HOP_BY_HOP_HEADER_H__ 1

#include "IPv6ExtensionHeader.h"

#define HOP_BY_HOP_MAX_OPTIONS_LEN 256*8
#define HOPBYHOP_MIN_HEADER_LEN 8
#define HOPBYHOP_MAX_HEADER_LEN (HOPBYHOP_MIN_HEADER_LEN + HOP_BY_HOP_MAX_OPTIONS_LEN)
#define HOPBYHOP_MAX_OPTION_LEN 256

class HopByHopHeader : public IPv6ExtensionHeader {

    protected:
     /* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
        |  Next Header  |  Hdr Ext Len  |                               |
        +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+                               +
        |                                                               |
        .                                                               .
        .                            Options                            .
        .                                                               .
        |                                                               |
        +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ */
        struct nping_ipv6_ext_hopbyhop_hdr{
            u8 nh;
            u8 len;
            u8 options[HOP_BY_HOP_MAX_OPTIONS_LEN];
        }__attribute__((__packed__));
        typedef struct nping_ipv6_ext_hopbyhop_hdr nping_ipv6_ext_hopbyhop_hdr_t;


     /* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+- - - - - - - - -
        |  Option Type  |  Opt Data Len |  Option Data
        +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+- - - - - - - - - */
        struct nping_ipv6_ext_hopbyhop_opt{
            u8 type;
            u8 len;
            u8 data[HOPBYHOP_MAX_OPTION_LEN];
        }__attribute__((__packed__));
        typedef struct nping_ipv6_ext_hopbyhop_opt nping_ipv6_ext_hopbyhop_opt_t;

        nping_ipv6_ext_hopbyhop_hdr_t h;
        u8 *curr_option;

    public:
        HopByHopHeader();
        ~HopByHopHeader();
        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;

        /* Protocol specific methods */
        int setNextHeader(u8 val);
        u8 getNextHeader();

        int addOption(u8 type, u8 len, const u8 *data);
        int addPadding();

}; /* End of class HopByHopHeader */

#endif
