/*
 ###############################
 ##### UH EXTENDED INFO MASKS
 ###############################
 */

/**< Next field mask. */
#define UH_NEXT_FIELD_MASK       0xC0

/**< Next field type mask. */
#define UH_NEXT_FIELD_TYPE_MASK  0x20

/**< IP version mask. */
#define UH_IP_VERSION_MASK       0x10

/**< IP validity mask. */
#define UH_IP_VALID_MASK         0x8

/**< Frag. validity mask. */
#define UH_FRAG_VALID_MASK       0x4

/**< Fragmntation mask. */
#define UH_FRAGMENTATION_MASK    0x3

/*
 ###############################
 ##### UH EXTENDED INFO MASKS
 ###############################
 */

/**< Set next field to MPLS, usage: extended_info |= UH_SET_NEXT_FIELD_MPLS */
#define UH_SET_NEXT_FIELD_MPLS 0x40

/**< Set next field to VLAN, usage: extended_info |= UH_SET_NEXT_FIELD_ONE_VLAN */
#define UH_SET_NEXT_FIELD_ONE_VLAN 0x80

/**< Set next field to two VLANs, usage: extended_info |= UH_SET_NEXT_FIELD_TWO_VLANS */
#define UH_SET_NEXT_FIELD_TWO_VLANS 0xC0

/**< Set next field to zero (unused), usage: extended_info &= UH_SET_NEXT_FIELD_UNUSED */
#define UH_SET_NEXT_FIELD_UNUSED ~(1 << 0xC0)

/**< Set IP version to IPv4, usage: extended_info &= UH_SET_IP_VERSION_V4 */
#define UH_SET_IP_VERSION_V4 ~(1 << 0x10)

/**< Set IP version to IPv6, usage: extended_info |= UH_SET_IP_VERSION_V6 */
#define UH_SET_IP_VERSION_V6 0x10

/**< Set IP validity to true, usage: extended_info |= UH_SET_IP_VALID */
#define UH_SET_IP_VALID 0x8

/**< Set IP validity to false, usage: extended_info &= UH_SET_IP_INVALID */
#define UH_SET_IP_INVALID ~(1 << 0x8)

/**< Set fragmentation validity to true, usage: extended_info |= UH_SET_FRAG_VALID */
#define UH_SET_FRAG_VALID 0x4

/**< Set fragmentation validity to false, usage: extended_info |= UH_SET_FRAG_INVALID */
#define UH_SET_FRAG_INVALID ~(1 << 0x4)

/**
 * @brief Structure containing important information about packet.
 */
struct uh_header_s {
    ip_addr_t src_ip;          /**< Source IP address */
    ip_addr_t dst_ip;          /**< Destination IP address */
    uint16_t src_port;         /**< Source port */
    uint16_t dst_port;         /**< Destination port */
    uint16_t octets;           /**< Packet length. (without CRC) */
    uint8_t protocol;          /**< Protocol number */
    uint8_t extended_info;     /**<  Bits:  (HSB) |    00      |        0        |      0     |     0    |      0      |     00    | (LSB)
                                     Field:       | next field | next field type | ip version | ip valid | frag. valid | frag. type|

                                     next field: 0 - unsued, 1 - MPLS, 2 - (one VLAN), 3 - (two VLANs).
                                     next field type: unused
                                     ip version: 0 - IPv4, 1 - IPv6
                                     ip valid: 0 - invalid IP packet, 1 - valid
                                     fragmentation valid: 1 - fragmentation type is valid
                                     fragmentation type: 0 - mid, 1 - last, 2 - first, 3 - no fragment.
                                */
    uint16_t vlanid;           /**< Vlan ID */
    uint16_t inner_mpls_vlan;  /**< Unsued. */
    uint8_t tcp_flags;  /**< TCP flags: bit position - FIN(0), SYN(1), RST(2), PSH(3), ACK(4), URG(5), ECE(6), CWR(7) */
};