void Create_IP_Header(unsigned char *ip_header, unsigned char protocol, unsigned int total_len,
                      unsigned int id, unsigned long src_addr, unsigned long dst_addr)
{
  *((unsigned char*)ip_header + IP_HDR_VER_LEN) = 0x45;                                         //Version + IHL
  *((unsigned char*)ip_header + IP_HDR_TOS) = 0x00;                                             //ToS
  *(unsigned int*)(unsigned char*)((unsigned char*)ip_header + IP_HDR_TOTAL_LEN) = __reverse(total_len);        //Total Lenghth
  *(unsigned int*)(unsigned char*)((unsigned char*)ip_header + IP_HDR_ID) = __reverse(id);      //Identification
  *((unsigned char*)ip_header + (IP_HDR_FLAG_FRGT_OFFSET + 0)) = 0x40;                          //Flags + Fragment Offset. MF = 0, DF = 1
  *((unsigned char*)ip_header + (IP_HDR_FLAG_FRGT_OFFSET + 1)) = 0x00;                          //Fragment Offset
  *((unsigned char*)ip_header + IP_HDR_TTL) = 0x80;                                             //TTL
  *((unsigned char*)ip_header + IP_HDR_PROTOCOL) = protocol;                                    //Protocol
  *(unsigned int*)(unsigned char*)((unsigned char*)ip_header + IP_HDR_CHECKSUM) = 0;                            //IP Checksum
  *(unsigned long*)(unsigned char*)((unsigned char*)ip_header + IP_HDR_SRC_ADDR) = __reverse(src_addr);         //SRC IP ADDR
  *(unsigned long*)(unsigned char*)((unsigned char*)ip_header + IP_HDR_DST_ADDR) = __reverse(dst_addr);         //DST IP ADDR
}

tupdef union{
uint8 raw_data[2000];
//---------------------------------
struct{
    uint8 ip_header;
    uint8 tos;
    ……    
}IP;
//--------------------------------
struct{
    uint8 shift[32];  //пропускаем IP заголовок
    uint16  PORT_surce;
uint16  PORT_distenation;
    ……    
}TCP;
//----------------------------------
struct{
    uint8 shift[32];  //пропускаем IP заголовок
    ……    
}UDP;
}IP_FRAME;