http_protocol_handler.inl

Go to the documentation of this file.

// Copyright (c) 2006-2013, Andrey N. Sabelnikov, www.sabelnikov.net
// All rights reserved.
// 
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are met:
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above copyright
// notice, this list of conditions and the following disclaimer in the
// documentation and/or other materials provided with the distribution.
// * Neither the name of the Andrey N. Sabelnikov nor the
// names of its contributors may be used to endorse or promote products
// derived from this software without specific prior written permission.
// 
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
// ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
// WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
// DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER  BE LIABLE FOR ANY
// DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
// (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
// LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
// ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
// 
 
 
#include <boost/algorithm/string/predicate.hpp>
#include <boost/lexical_cast.hpp>
#include <boost/regex.hpp>
#include "http_protocol_handler.h"
#include "reg_exp_definer.h"
#include "string_tools.h"
#include "file_io_utils.h"
#include "net_parse_helpers.h"
#include "time_helper.h"
 
#undef MONERO_DEFAULT_LOG_CATEGORY
#define MONERO_DEFAULT_LOG_CATEGORY "net.http"
 
#define HTTP_MAX_URI_LEN         9000 
#define HTTP_MAX_HEADER_LEN      100000
#define HTTP_MAX_STARTING_NEWLINES       8
 
namespace epee
{
namespace net_utils
{
    namespace http
    {
 
        struct multipart_entry
        {
            std::list<std::pair<std::string, std::string> > m_etc_header_fields;
            std::string m_content_disposition;
            std::string m_content_type;
            std::string m_body;
        };
 
        inline
            bool match_boundary(const std::string& content_type, std::string& boundary)
        {
            STATIC_REGEXP_EXPR_1(rexp_match_boundary, "boundary=(.*?)(($)|([;\\s,]))", boost::regex::icase | boost::regex::normal);
            //                                                  1
            boost::smatch result;   
            if(boost::regex_search(content_type, result, rexp_match_boundary, boost::match_default) && result[0].matched)
            {
                boundary = result[1];
                return true;
            }
 
            return false;
        }
 
        inline 
            bool parse_header(std::string::const_iterator it_begin, std::string::const_iterator it_end, multipart_entry& entry)
        {
            STATIC_REGEXP_EXPR_1(rexp_mach_field, 
                "\n?((Content-Disposition)|(Content-Type)"
                //  12                     3 
                "|([\\w-]+?)) ?: ?((.*?)(\r?\n))[^\t ]",    
                //4               56    7 
                boost::regex::icase | boost::regex::normal);
 
            boost::smatch       result;
            std::string::const_iterator it_current_bound = it_begin;
            std::string::const_iterator it_end_bound = it_end;
 
            //lookup all fields and fill well-known fields
            while( boost::regex_search( it_current_bound, it_end_bound, result, rexp_mach_field, boost::match_default) && result[0].matched) 
            {
                const size_t field_val = 6;
                const size_t field_etc_name = 4;
 
                int i = 2; //start position = 2
                if(result[i++].matched)//"Content-Disposition"
                    entry.m_content_disposition = result[field_val];
                else if(result[i++].matched)//"Content-Type"
                    entry.m_content_type = result[field_val];
                else if(result[i++].matched)//e.t.c (HAVE TO BE MATCHED!)
                    entry.m_etc_header_fields.push_back(std::pair<std::string, std::string>(result[field_etc_name], result[field_val]));
                else
                {
                    LOG_ERROR("simple_http_connection_handler::parse_header() not matched last entry in:"<<std::string(it_current_bound, it_end));
                }
 
                it_current_bound = result[(int)result.size()-1].first;
            }
            return  true;
        }
 
        inline
            bool handle_part_of_multipart(std::string::const_iterator it_begin, std::string::const_iterator it_end, multipart_entry& entry)
        {
            std::string end_str = "\r\n\r\n";
            std::string::const_iterator end_header_it = std::search(it_begin, it_end, end_str.begin(), end_str.end());
            if(end_header_it == it_end)
            {
                //header not matched 
                return false;
            }
 
            if(!parse_header(it_begin, end_header_it+4, entry))
            {
                LOG_ERROR("Failed to parse header:" << std::string(it_begin, end_header_it+2));
                return false;
            }
        
            entry.m_body.assign(end_header_it+4, it_end);
 
            return true;
        }
 
        inline
            bool parse_multipart_body(const std::string& content_type, const std::string& body, std::list<multipart_entry>& out_values)
        {
            //bool res = file_io_utils::load_file_to_string("C:\\public\\multupart_data", body);
 
            std::string boundary;
            if(!match_boundary(content_type, boundary))
            {
                MERROR("Failed to match boundary in content type: " << content_type);
                return false;
            }
            
            boundary+="\r\n";
            bool is_stop = false;
            bool first_step = true;
            
            std::string::const_iterator it_begin = body.begin();
            std::string::const_iterator it_end;
            while(!is_stop)
            {
                std::string::size_type pos = body.find(boundary, std::distance(body.begin(), it_begin));
            
                if(std::string::npos == pos)
                {
                    is_stop = true;
                    boundary.erase(boundary.size()-2, 2);
                    boundary+= "--";
                    pos = body.find(boundary, std::distance(body.begin(), it_begin));
                    if(std::string::npos == pos)
                    {
                        MERROR("Error: Filed to match closing multipart tag");
                        it_end = body.end();
                    }else
                    {
                        it_end =  body.begin() + pos;
                    }
                }else
                    it_end =  body.begin() + pos;
 
            
                if(first_step && !is_stop)
                {
                    first_step = false;
                    it_begin = it_end + boundary.size();
                    std::string temp = "\r\n--";
                    boundary = temp + boundary;
                    continue;
                }
                
                out_values.push_back(multipart_entry());
                if(!handle_part_of_multipart(it_begin, it_end, out_values.back()))
                {
                    MERROR("Failed to handle_part_of_multipart");
                    return false;
                }
 
                it_begin = it_end + boundary.size();
            }
 
            return true;
        }
 
 
 
 
        //--------------------------------------------------------------------------------------------
        template<class t_connection_context>
        simple_http_connection_handler<t_connection_context>::simple_http_connection_handler(i_service_endpoint* psnd_hndlr, config_type& config, t_connection_context& conn_context):
        m_state(http_state_retriving_comand_line),
        m_body_transfer_type(http_body_transfer_undefined),
        m_is_stop_handling(false),
        m_len_summary(0),
        m_len_remain(0),
        m_config(config),
        m_want_close(false),
        m_newlines(0),
        m_bytes_read(0),
        m_psnd_hndlr(psnd_hndlr),
        m_conn_context(conn_context),
        m_initialized(false)
    {
 
    }
    //--------------------------------------------------------------------------------------------
    template<class t_connection_context>
    simple_http_connection_handler<t_connection_context>::~simple_http_connection_handler()
    {
      try
      {
        if (m_initialized)
        {
          CRITICAL_REGION_LOCAL(m_config.m_lock);
          if (m_config.m_connection_count)
            --m_config.m_connection_count;
          auto elem = m_config.m_connections.find(m_conn_context.m_remote_address.host_str());
          if (elem != m_config.m_connections.end())
          {
            if (elem->second == 1 || elem->second == 0)
              m_config.m_connections.erase(elem);
            else
              --(elem->second);
          }
        }
      }
      catch (...)
      {}
    }
    //--------------------------------------------------------------------------------------------
    template<class t_connection_context>
    bool simple_http_connection_handler<t_connection_context>::after_init_connection()
    {
      CRITICAL_REGION_LOCAL(m_config.m_lock);
      ++m_config.m_connections[m_conn_context.m_remote_address.host_str()];
      ++m_config.m_connection_count;
      m_initialized = true;
      return true;
    }
    //--------------------------------------------------------------------------------------------
    template<class t_connection_context>
    bool simple_http_connection_handler<t_connection_context>::set_ready_state()
    {
        m_is_stop_handling = false;
        m_state = http_state_retriving_comand_line;
        m_body_transfer_type = http_body_transfer_undefined;
        m_query_info.clear();
        m_len_summary = 0;
        m_newlines = 0;
        m_bytes_read = 0;
        return true;
    }
    //--------------------------------------------------------------------------------------------
  template<class t_connection_context>
    bool simple_http_connection_handler<t_connection_context>::handle_recv(const void* ptr, size_t cb)
    {
        std::string buf((const char*)ptr, cb);
        //LOG_PRINT_L0("HTTP_RECV: " << ptr << "\r\n" << buf);
        //file_io_utils::save_string_to_file(string_tools::get_current_module_folder() + "/" + boost::lexical_cast<std::string>(ptr), std::string((const char*)ptr, cb));
 
        bool res = handle_buff_in(buf);
        if(m_want_close/*m_state == http_state_connection_close || m_state == http_state_error*/)
            return false;
        return res;
    }
    //--------------------------------------------------------------------------------------------
  template<class t_connection_context>
    bool simple_http_connection_handler<t_connection_context>::handle_buff_in(std::string& buf)
    {
 
        size_t ndel;
 
        m_bytes_read += buf.size();
        if (m_bytes_read > m_config.m_max_content_length)
        {
            LOG_ERROR("simple_http_connection_handler::handle_buff_in: Too much data: got " << m_bytes_read);
            m_state = http_state_error;
            return false;
        }
 
        if(m_cache.size())
            m_cache += buf;
        else
            m_cache.swap(buf);
 
        m_is_stop_handling = false;
        while(!m_is_stop_handling)
        {
            switch(m_state)
            {
            case http_state_retriving_comand_line:
                //The HTTP protocol does not place any a priori limit on the length of a URI.  (c)RFC2616
                //but we forebly restirct it len to HTTP_MAX_URI_LEN to make it more safely
                if(!m_cache.size())
                    break;
 
                //check_and_handle_fake_response();
                ndel = m_cache.find_first_not_of("\r\n");
                if (ndel != 0)
                {
          //some times it could be that before query line cold be few line breaks
          //so we have to be calm without panic with assers
                    m_newlines += std::string::npos == ndel ? m_cache.size() : ndel;
                    if (m_newlines > HTTP_MAX_STARTING_NEWLINES)
                    {
                        LOG_ERROR("simple_http_connection_handler::handle_buff_out: Too many starting newlines");
                        m_state = http_state_error;
                        return false;
                    }
                    m_cache.erase(0, ndel);
                    break;
                }
 
                if(std::string::npos != m_cache.find('\n', 0))
                    handle_invoke_query_line();
                else
                {
                    m_is_stop_handling = true;
                    if(m_cache.size() > HTTP_MAX_URI_LEN)
                    {
                        LOG_ERROR_CC(m_conn_context, "simple_http_connection_handler::handle_buff_out: Too long URI line");
                        m_state = http_state_error;
                        return false;
                    }
                }
                break;
            case http_state_retriving_header:
                {
                    std::string::size_type pos = match_end_of_header(m_cache);
                    if(std::string::npos == pos)
                    {
                        m_is_stop_handling = true;
                        if(m_cache.size() > HTTP_MAX_HEADER_LEN)
                        {
                            LOG_ERROR_CC(m_conn_context, "simple_http_connection_handler::handle_buff_in: Too long header area");
                            m_state = http_state_error;
                            return false;
                        }   
                        break;
                    }
                    if (!analize_cached_request_header_and_invoke_state(pos))
                        return false;
                    break;
                }
            case http_state_retriving_body:
                return handle_retriving_query_body();
            case http_state_connection_close:
                return false;
            default:
                LOG_ERROR_CC(m_conn_context, "simple_http_connection_handler::handle_char_out: Wrong state: " << m_state);
                return false;
            case http_state_error:
                LOG_ERROR_CC(m_conn_context, "simple_http_connection_handler::handle_char_out: Error state!!!");
                return false;
            }
 
            if(!m_cache.size())
                m_is_stop_handling = true;
        }
 
        return true;
    }
    //--------------------------------------------------------------------------------------------
    inline bool analize_http_method(const boost::smatch& result, http::http_method& method, int& http_ver_major, int& http_ver_minor)
    {
        CHECK_AND_ASSERT_MES(result[0].matched, false, "simple_http_connection_handler::analize_http_method() assert failed...");
        if (!boost::conversion::try_lexical_convert<int>(result[11], http_ver_major))
            return false;
        if (!boost::conversion::try_lexical_convert<int>(result[12], http_ver_minor))
            return false;
 
        if(result[3].matched)
            method = http::http_method_options;
        else if(result[4].matched)
            method = http::http_method_get;
        else if(result[5].matched)
            method = http::http_method_head;
        else if(result[6].matched)
            method = http::http_method_post;
        else if(result[7].matched)
            method = http::http_method_put;
        else 
            method = http::http_method_etc;
 
        return true;
    }
 
  //--------------------------------------------------------------------------------------------
  template<class t_connection_context>
    bool simple_http_connection_handler<t_connection_context>::handle_invoke_query_line()
    { 
        STATIC_REGEXP_EXPR_1(rexp_match_command_line, "^(((OPTIONS)|(GET)|(HEAD)|(POST)|(PUT)|(DELETE)|(TRACE)) (\\S+) HTTP/(\\d+)\\.(\\d+))\r?\n", boost::regex::icase | boost::regex::normal);
        //                                              123         4     5      6      7     8        9        10          11     12    
        //size_t match_len = 0;
        boost::smatch result;   
        if(boost::regex_search(m_cache, result, rexp_match_command_line, boost::match_default) && result[0].matched)
        {
            if (!analize_http_method(result, m_query_info.m_http_method, m_query_info.m_http_ver_hi, m_query_info.m_http_ver_hi))
            {
                m_state = http_state_error;
                MERROR("Failed to analyze method");
                return false;
            }
            m_query_info.m_URI = result[10];
            if (!parse_uri(m_query_info.m_URI, m_query_info.m_uri_content))
            {
                m_state = http_state_error;
                MERROR("Failed to parse URI: m_query_info.m_URI");
                return false;
            }
            m_query_info.m_http_method_str = result[2];
            m_query_info.m_full_request_str = result[0];
 
            m_cache.erase(m_cache.begin(), result[0].second);
 
            m_state = http_state_retriving_header;
 
            return true;
        }else
        {
            m_state = http_state_error;
            LOG_ERROR_CC(m_conn_context, "simple_http_connection_handler<t_connection_context>::handle_invoke_query_line(): Failed to match first line: " << m_cache);
            return false;
        }
 
        return false;
    }
    //--------------------------------------------------------------------------------------------
  template<class t_connection_context>
    std::string::size_type simple_http_connection_handler<t_connection_context>::match_end_of_header(const std::string& buf)
    {
 
    //Here we returning head size, including terminating sequence (\r\n\r\n or \n\n)
        std::string::size_type res = buf.find("\r\n\r\n");
        if(std::string::npos != res)
            return res+4;
        res = buf.find("\n\n");
        if(std::string::npos != res)
            return res+2;
        return res;
    }
    //--------------------------------------------------------------------------------------------
  template<class t_connection_context>
    bool simple_http_connection_handler<t_connection_context>::analize_cached_request_header_and_invoke_state(size_t pos)
    { 
        LOG_PRINT_L3("HTTP HEAD:\r\n" << m_cache.substr(0, pos));
 
        m_query_info.m_full_request_buf_size = pos;
    m_query_info.m_request_head.assign(m_cache.begin(), m_cache.begin()+pos); 
 
        if(!parse_cached_header(m_query_info.m_header_info, m_cache, pos))
        {
            LOG_ERROR_CC(m_conn_context, "simple_http_connection_handler<t_connection_context>::analize_cached_request_header_and_invoke_state(): failed to anilize request header: " << m_cache);
            m_state = http_state_error;
            return false;
        }
 
        m_cache.erase(0, pos);
 
        std::string req_command_str = m_query_info.m_full_request_str;
    //if we have POST or PUT command, it is very possible tha we will get body
    //but now, we suppose than we have body only in case of we have "ContentLength" 
        if(m_query_info.m_header_info.m_content_length.size())
        {
            m_state = http_state_retriving_body;
            m_body_transfer_type = http_body_transfer_measure;
            if(!get_len_from_content_lenght(m_query_info.m_header_info.m_content_length, m_len_summary))
            {
                LOG_ERROR_CC(m_conn_context, "simple_http_connection_handler<t_connection_context>::analize_cached_request_header_and_invoke_state(): Failed to get_len_from_content_lenght();, m_query_info.m_content_length="<<m_query_info.m_header_info.m_content_length);
                m_state = http_state_error;
                return false;
            }
            if(0 == m_len_summary)
            {   //current query finished, next will be next query
                if(handle_request_and_send_response(m_query_info))
                    set_ready_state();
                else
                    m_state = http_state_error;
            }
            m_len_remain = m_len_summary;
        }else
        {//current query finished, next will be next query
            handle_request_and_send_response(m_query_info);
            set_ready_state();
        }
 
        return true;
    }
    //-----------------------------------------------------------------------------------
  template<class t_connection_context>
    bool simple_http_connection_handler<t_connection_context>::handle_retriving_query_body()
    {
        switch(m_body_transfer_type)
        {
        case http_body_transfer_measure:
            return handle_query_measure();
        case http_body_transfer_chunked:
        case http_body_transfer_connection_close:
        case http_body_transfer_multipart:
        case http_body_transfer_undefined:
        default:
            LOG_ERROR_CC(m_conn_context, "simple_http_connection_handler<t_connection_context>::handle_retriving_query_body(): Unexpected m_body_query_type state:" << m_body_transfer_type);
            m_state = http_state_error;
            return false;
        }
 
        return true;
    }
    //-----------------------------------------------------------------------------------
  template<class t_connection_context>
    bool simple_http_connection_handler<t_connection_context>::handle_query_measure()
    {
 
        if(m_len_remain >= m_cache.size())
        {
            m_len_remain -= m_cache.size();
            m_query_info.m_body += m_cache;
            m_cache.clear();
        }else
        {
            m_query_info.m_body.append(m_cache.begin(), m_cache.begin() + m_len_remain);
            m_cache.erase(0, m_len_remain);
            m_len_remain = 0;
        }
 
        if(!m_len_remain)
        {
            if(handle_request_and_send_response(m_query_info))
                set_ready_state();
            else
                m_state = http_state_error;
        }
        return true;
    }
    //--------------------------------------------------------------------------------------------
  template<class t_connection_context>
    bool simple_http_connection_handler<t_connection_context>::parse_cached_header(http_header_info& body_info, const std::string& m_cache_to_process, size_t pos)
    { 
        body_info.clear();
        if(pos > m_cache_to_process.size() || pos > HTTP_MAX_HEADER_LEN)
            return false;
 
        size_t cur = 0;
 
        while(cur < pos)
        {
            const size_t line_end = m_cache_to_process.find('\n', cur);
            if(line_end == std::string::npos || line_end >= pos)
                break;
 
            boost::string_view line(m_cache_to_process.data() + cur, line_end - cur);
            cur = line_end + 1;
 
            // End of header block.
            if(line == "\r" || line.empty())
                break;
 
            boost::string_view name;
            boost::string_view value;
            if(!detail::parse_header_line(line, name, value))
                return false;
 
            if(boost::iequals(name, "Connection"))
                body_info.m_connection = std::string(value.data(), value.size());
            else if(boost::iequals(name, "Referer"))
                body_info.m_referer = std::string(value.data(), value.size());
            else if(boost::iequals(name, "Content-Length"))
                body_info.m_content_length = std::string(value.data(), value.size());
            else if(boost::iequals(name, "Content-Type"))
                body_info.m_content_type = std::string(value.data(), value.size());
            else if(boost::iequals(name, "Transfer-Encoding"))
                body_info.m_transfer_encoding = std::string(value.data(), value.size());
            else if(boost::iequals(name, "Content-Encoding"))
                body_info.m_content_encoding = std::string(value.data(), value.size());
            else if(boost::iequals(name, "Host"))
                body_info.m_host = std::string(value.data(), value.size());
            else if(boost::iequals(name, "Cookie"))
                body_info.m_cookie = std::string(value.data(), value.size());
            else if(boost::iequals(name, "User-Agent"))
                body_info.m_user_agent = std::string(value.data(), value.size());
            else if(boost::iequals(name, "Origin"))
                body_info.m_origin = std::string(value.data(), value.size());
            else
                body_info.m_etc_fields.push_back(std::make_pair(std::string(name.data(), name.size()), std::string(value.data(), value.size())));
        }
        return  true;
    }
    //-----------------------------------------------------------------------------------
  template<class t_connection_context>
    bool simple_http_connection_handler<t_connection_context>::get_len_from_content_lenght(const std::string& str, size_t& OUT len)
    {
        STATIC_REGEXP_EXPR_1(rexp_mach_field, "\\d+", boost::regex::normal);
        std::string res;
        boost::smatch result;
        if(!(boost::regex_search( str, result, rexp_mach_field, boost::match_default) && result[0].matched))
            return false;
 
        try { len = boost::lexical_cast<size_t>(result[0]); }
        catch(...) { return false; }
        return true;
    }
    //-----------------------------------------------------------------------------------
  template<class t_connection_context>
    bool simple_http_connection_handler<t_connection_context>::handle_request_and_send_response(const http::http_request_info& query_info)
    {
        http_response_info response{};
        //CHECK_AND_ASSERT_MES(res, res, "handle_request(query_info, response) returned false" );
        bool res = true;
 
        if (query_info.m_http_method != http::http_method_options)
        {
            res = handle_request(query_info, response);
            if (response.m_response_code == 500)
            {
                m_want_close = true;    // close on all "Internal server error"s
            }
        }
        else
        {
            response.m_response_code = 200;
            response.m_response_comment = "OK";
        }
 
        std::string response_data = get_response_header(response);
        //LOG_PRINT_L0("HTTP_SEND: << \r\n" << response_data + response.m_body);
 
        LOG_PRINT_L3("HTTP_RESPONSE_HEAD: << \r\n" << response_data);
 
        if ((response.m_body.size() && (query_info.m_http_method != http::http_method_head)) || (query_info.m_http_method == http::http_method_options))
            response_data += response.m_body;
 
        m_psnd_hndlr->do_send(byte_slice{std::move(response_data)});
        m_psnd_hndlr->send_done();
        return res;
    }
    //-----------------------------------------------------------------------------------
  template<class t_connection_context>
    bool simple_http_connection_handler<t_connection_context>::handle_request(const http::http_request_info& query_info, http_response_info& response)
    {
 
        std::string uri_to_path = query_info.m_uri_content.m_path;
        if("/" == uri_to_path)
            uri_to_path = "/index.html";
 
        //slash_to_back_slash(uri_to_path);
        m_config.m_lock.lock();
        std::string destination_file_path = m_config.m_folder + uri_to_path;
        m_config.m_lock.unlock();
        if(!file_io_utils::load_file_to_string(destination_file_path.c_str(), response.m_body))
        {
            MWARNING("URI \""<< query_info.m_full_request_str.substr(0, query_info.m_full_request_str.size()-2) << "\" [" << destination_file_path << "] Not Found (404 )");
            response.m_body = get_not_found_response_body(query_info.m_URI);
            response.m_response_code = 404;
            response.m_response_comment = "Not found";
            response.m_mime_tipe = "text/html";
            return true;
        }
 
        MDEBUG(" -->> " << query_info.m_full_request_str << "\r\n<<--OK");
        response.m_response_code = 200;
        response.m_response_comment = "OK";
        response.m_mime_tipe = get_file_mime_tipe(uri_to_path);
 
        return true;
    }
    //-----------------------------------------------------------------------------------
  template<class t_connection_context>
    std::string simple_http_connection_handler<t_connection_context>::get_response_header(const http_response_info& response)
    {
        std::string buf = "HTTP/1.1 ";
        buf += boost::lexical_cast<std::string>(response.m_response_code) + " " + response.m_response_comment + "\r\n" +
            "Server: Epee-based\r\n"
            "Content-Length: ";
        buf += boost::lexical_cast<std::string>(response.m_body.size()) + "\r\n";
 
        if(!response.m_mime_tipe.empty())
        {
            buf += "Content-Type: ";
            buf += response.m_mime_tipe + "\r\n";
        }
 
        buf += "Last-Modified: ";
        time_t tm;
        time(&tm);
        buf += misc_utils::get_internet_time_str(tm) + "\r\n";
        buf += "Accept-Ranges: bytes\r\n";
        //Wed, 01 Dec 2010 03:27:41 GMT"
 
        string_tools::trim(m_query_info.m_header_info.m_connection);
        if(m_query_info.m_header_info.m_connection.size())
        {
            if(!string_tools::compare_no_case("close", m_query_info.m_header_info.m_connection))
            {
        //closing connection after sending
                buf += "Connection: close\r\n";
                m_state = http_state_connection_close;
                m_want_close = true;
            }
        }
 
        // Cross-origin resource sharing
        if(m_query_info.m_header_info.m_origin.size())
        {
            if (std::binary_search(m_config.m_access_control_origins.begin(), m_config.m_access_control_origins.end(), "*") || std::binary_search(m_config.m_access_control_origins.begin(), m_config.m_access_control_origins.end(), m_query_info.m_header_info.m_origin))
            {
                buf += "Access-Control-Allow-Origin: ";
                buf += m_query_info.m_header_info.m_origin;
                buf += "\r\n";
                buf += "Access-Control-Expose-Headers: www-authenticate\r\n";
                if (m_query_info.m_http_method == http::http_method_options)
                    buf += "Access-Control-Allow-Headers: Content-Type, Authorization, X-Requested-With\r\n";
                buf += "Access-Control-Allow-Methods: POST, PUT, GET, OPTIONS\r\n";
            }
        }
 
        //add additional fields, if it is
        for(fields_list::const_iterator it = response.m_additional_fields.begin(); it!=response.m_additional_fields.end(); it++)
            buf += it->first + ": " + it->second + "\r\n";
 
        buf+="\r\n";
 
        return buf;
    }
    //-----------------------------------------------------------------------------------
    template<class t_connection_context>
  std::string simple_http_connection_handler<t_connection_context>::get_file_mime_tipe(const std::string& path)
    {
        std::string result;
        std::string ext = string_tools::get_extension(path);
        if(!string_tools::compare_no_case(ext, "gif"))
            result = "image/gif";
        else if(!string_tools::compare_no_case(ext, "jpg"))
            result = "image/jpeg";
        else if(!string_tools::compare_no_case(ext, "html"))
            result = "text/html";
        else if(!string_tools::compare_no_case(ext, "htm"))
            result = "text/html";
        else if(!string_tools::compare_no_case(ext, "js"))
            result = "application/x-javascript";
        else if(!string_tools::compare_no_case(ext, "css"))
            result = "text/css";
        else if(!string_tools::compare_no_case(ext, "xml"))
            result = "application/xml";
    else if(!string_tools::compare_no_case(ext, "svg"))
      result = "image/svg+xml";
 
 
        return result;
    }
    //-----------------------------------------------------------------------------------
    template<class t_connection_context>
  std::string simple_http_connection_handler<t_connection_context>::get_not_found_response_body(const std::string& URI)
    {
        std::string body = 
            "<!DOCTYPE HTML PUBLIC \"-//IETF//DTD HTML 2.0//EN\">\r\n"
            "<html><head>\r\n"
            "<title>404 Not Found</title>\r\n"
            "</head><body>\r\n"
            "<h1>Not Found</h1>\r\n"
            "<p>The requested URL \r\n";
        body += URI;
        body += "was not found on this server.</p>\r\n"
            "</body></html>\r\n";
 
        return body;
    }
    //--------------------------------------------------------------------------------------------
    template<class t_connection_context>
  bool simple_http_connection_handler<t_connection_context>::slash_to_back_slash(std::string& str)
    {
        for(std::string::iterator it = str.begin(); it!=str.end(); it++)
            if('/' == *it)
                *it = '\\';
        return true;
    }
    }
}
}
 
//--------------------------------------------------------------------------------------------
//--------------------------------------------------------------------------------------------
//--------------------------------------------------------------------------------------------