/***************************************************************************
 * ICMPv6Option.h -- The ICMPv6Option Class represents an ICMP version 6   *
 * option. 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 __ICMPv6OPTION_H__
#define __ICMPv6OPTION_H__ 1

#include "NetworkLayerElement.h"

/* Packet header diagrams included in this file have been taken from the
 * following IETF RFC documents: RFC 2461, RFC 2894 */

/* The following codes have been defined by IANA. A complete list may be found
 * at http://www.iana.org/assignments/icmpv6-parameters */

/* ICMPv6 Option Types */
#define ICMPv6_OPTION_SRC_LINK_ADDR 1
#define ICMPv6_OPTION_TGT_LINK_ADDR 2
#define ICMPv6_OPTION_PREFIX_INFO   3
#define ICMPv6_OPTION_REDIR_HDR     4
#define ICMPv6_OPTION_MTU           5

/* Nping ICMPv6Options Class internal definitions */
#define ICMPv6_OPTION_COMMON_HEADER_LEN    2
#define ICMPv6_OPTION_MIN_HEADER_LEN       8
#define ICMPv6_OPTION_SRC_LINK_ADDR_LEN    (ICMPv6_OPTION_COMMON_HEADER_LEN+6)
#define ICMPv6_OPTION_TGT_LINK_ADDR_LEN    (ICMPv6_OPTION_COMMON_HEADER_LEN+6)
#define ICMPv6_OPTION_PREFIX_INFO_LEN      (ICMPv6_OPTION_COMMON_HEADER_LEN+30)
#define ICMPv6_OPTION_REDIR_HDR_LEN        (ICMPv6_OPTION_COMMON_HEADER_LEN+6)
#define ICMPv6_OPTION_MTU_LEN              (ICMPv6_OPTION_COMMON_HEADER_LEN+6)
/* This must the MAX() of all values defined above*/
#define ICMPv6_OPTION_MAX_MESSAGE_BODY     (ICMPv6_OPTION_PREFIX_INFO_LEN-ICMPv6_OPTION_COMMON_HEADER_LEN)

#define ICMPv6_OPTION_LINK_ADDRESS_LEN 6

class ICMPv6Option : public NetworkLayerElement {

    private:

        /**********************************************************************/
        /* COMMON ICMPv6 OPTION HEADER                                        */
        /**********************************************************************/

        struct nping_icmpv6_option{
            u8 type;
            u8 length;
            u8 data[ICMPv6_OPTION_MAX_MESSAGE_BODY];
        }__attribute__((__packed__));
        typedef struct nping_icmpv6_option nping_icmpv6_option_t;

        /**********************************************************************/
        /* ICMPv6 OPTION FORMATS                                              */
        /**********************************************************************/
        /* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
           |     Type      |    Length     |              ...              |
           +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
           ~                              ...                              ~
           +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ */


        /* Source/Target Link-layer Address
          +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
          |     Type      |    Length     |    Link-Layer Address ...
          +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ */
        struct link_addr_option{
            u8 link_addr[6];
        }__attribute__((__packed__));
        typedef struct link_addr_option link_addr_option_t;


        /* Prefix Information
          +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
          |     Type      |    Length     | Prefix Length |L|A| Reserved1 |
          +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
          |                         Valid Lifetime                        |
          +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
          |                       Preferred Lifetime                      |
          +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
          |                           Reserved2                           |
          +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
          |                                                               |
          +                                                               +
          |                                                               |
          +                            Prefix                             +
          |                                                               |
          +                                                               +
          |                                                               |
          +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ */
        struct prefix_info_option{
            u8 prefix_length;
            u8 flags;
            u32 valid_lifetime;
            u32 preferred_lifetime;
            u32 reserved;
            u8 prefix[16];
        }__attribute__((__packed__));
        typedef struct prefix_info_option prefix_info_option_t;


        /* Redirect Header
          +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
          |     Type      |    Length     |            Reserved           |
          +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
          |                           Reserved                            |
          +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
          |                                                               |
          ~                       IP header + data                        ~
          |                                                               |
          +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ */
        struct redirect_option{
            u16 reserved_1;
            u32 reserved_2;
            //u8 invoking_pkt[?];
        }__attribute__((__packed__));
        typedef struct redirect_option redirect_option_t;


        /* MTU
          +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
          |     Type      |    Length     |           Reserved            |
          +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
          |                              MTU                              |
          +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ */
        struct mtu_option{
            u16 reserved;
            u32 mtu;
        }__attribute__((__packed__));
        typedef struct mtu_option mtu_option_t;


        nping_icmpv6_option_t h;

        link_addr_option_t        *h_la;
        prefix_info_option_t      *h_pi;
        redirect_option_t         *h_r;
        mtu_option_t              *h_mtu;

    public:
        ICMPv6Option();
        ~ICMPv6Option();
        void reset();
        u8 *getBufferPointer();
        int storeRecvData(const u8 *buf, size_t len);
        int protocol_id() const;

        int setType(u8 val);
        u8 getType();
        bool validateType(u8 val);

        int setLength(u8 val);
        u8 getLength();

        int setLinkAddress(u8* val);
        u8 *getLinkAddress();

        int setPrefixLength(u8 val);
        u8 getPrefixLength();

        int setFlags(u8 val);
        u8 getFlags();

        int setValidLifetime(u32 val);
        u32 getValidLifetime();

        int setPreferredLifetime(u32 val);
        u32 getPreferredLifetime();

        int setPrefix(u8 *val);
        u8 *getPrefix();

        int setMTU(u32 val);
        u32 getMTU();

        int getHeaderLengthFromType(u8 type);

}; /* End of class ICMPv6Option */

#endif
