pdns/minicurl.cc

   1 /*
   2  * MIT License
   3  *
   4  * Copyright (c) 2018-2019 powerdns.com bv
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a copy
   7  * of this software and associated documentation files (the "Software"), to deal
   8  * in the Software without restriction, including without limitation the rights
   9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  10  * copies of the Software, and to permit persons to whom the Software is
  11  * furnished to do so, subject to the following conditions:
  12  *
  13  * The above copyright notice and this permission notice shall be included in all
  14  * copies or substantial portions of the Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  19  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  22  * SOFTWARE.
  23  */
  24
  25 #include "minicurl.hh"
  26 #include <curl/curl.h>
  27 #include <stdexcept>
  28
  29 MiniCurl::MiniCurl(const string& useragent)
  30 {
  31   d_curl = curl_easy_init();
  32   if (d_curl != nullptr) {
  33     curl_easy_setopt(d_curl, CURLOPT_USERAGENT, useragent.c_str());
  34   }
  35 }
  36
  37 MiniCurl::~MiniCurl()
  38 {
  39   // NEEDS TO CLEAN HOSTLIST
  40   curl_easy_cleanup(d_curl);
  41 }
  42
  43 size_t MiniCurl::write_callback(char *ptr, size_t size, size_t nmemb, void *userdata)
  44 {
  45   MiniCurl* us = (MiniCurl*)userdata;
  46   us->d_data.append(ptr, size*nmemb);
  47   return size*nmemb;
  48 }
  49
  50 static string extractHostFromURL(const std::string& url)
  51 {
  52   auto pos = url.find("://");
  53   if(pos == string::npos)
  54     throw runtime_error("Can't find host part of '"+url+"'");
  55   pos += 3;
  56   auto endpos = url.find('/', pos);
  57   if(endpos == string::npos)
  58     return url.substr(pos);
  59
  60   return url.substr(pos, endpos-pos);
  61 }
  62
  63 void MiniCurl::setupURL(const std::string& str, const ComboAddress* rem, const ComboAddress* src)
  64 {
  65   if(rem) {
  66     struct curl_slist *hostlist = nullptr; // THIS SHOULD BE FREED
  67
  68     // url = http://hostname.enzo/url
  69     string host4=extractHostFromURL(str);
  70     // doest the host contain port indication
  71     std::size_t found = host4.find(':');
  72     vector<uint16_t> ports{80, 443};
  73     if (found != std::string::npos) {
  74       int port = std::stoi(host4.substr(found + 1));
  75       if (port <= 0 || port > 65535)
  76         throw std::overflow_error("Invalid port number");
  77       ports = {(uint16_t)port};
  78       host4 = host4.substr(0, found);
  79     }
  80
  81     for (const auto& port : ports) {
  82       string hcode = boost::str(boost::format("%s:%u:%s") % host4 % port % rem->toString());
  83       hostlist = curl_slist_append(hostlist, hcode.c_str());
  84     }
  85
  86     curl_easy_setopt(d_curl, CURLOPT_RESOLVE, hostlist);
  87   }
  88   if(src) {
  89     curl_easy_setopt(d_curl, CURLOPT_INTERFACE, src->toString().c_str());
  90   }
  91   curl_easy_setopt(d_curl, CURLOPT_FOLLOWLOCATION, true);
  92   /* only allow HTTP, TFTP and SFTP */
  93   curl_easy_setopt(d_curl, CURLOPT_PROTOCOLS, CURLPROTO_HTTP | CURLPROTO_HTTPS);
  94   curl_easy_setopt(d_curl, CURLOPT_SSL_VERIFYPEER, false);
  95   curl_easy_setopt(d_curl, CURLOPT_SSL_VERIFYHOST, false);
  96   curl_easy_setopt(d_curl, CURLOPT_FAILONERROR, true);
  97   curl_easy_setopt(d_curl, CURLOPT_URL, str.c_str());
  98   curl_easy_setopt(d_curl, CURLOPT_WRITEFUNCTION, write_callback);
  99   curl_easy_setopt(d_curl, CURLOPT_WRITEDATA, this);
 100   curl_easy_setopt(d_curl, CURLOPT_TIMEOUT, 2L);
 101
 102   d_data.clear();
 103 }
 104 std::string MiniCurl::getURL(const std::string& str, const ComboAddress* rem, const ComboAddress* src)
 105 {
 106   setupURL(str, rem, src);
 107   auto res = curl_easy_perform(d_curl);
 108   long http_code = 0;
 109   curl_easy_getinfo(d_curl, CURLINFO_RESPONSE_CODE, &http_code);
 110
 111   if(res != CURLE_OK || http_code != 200)  {
 112     throw std::runtime_error("Unable to retrieve URL ("+std::to_string(http_code)+"): "+string(curl_easy_strerror(res)));
 113   }
 114   std::string ret=d_data;
 115   d_data.clear();
 116   return ret;
 117 }
 118
 119 std::string MiniCurl::postURL(const std::string& str, const std::string& postdata)
 120 {
 121   setupURL(str);
 122   curl_easy_setopt(d_curl, CURLOPT_POSTFIELDS, postdata.c_str());
 123
 124   auto res = curl_easy_perform(d_curl);
 125   if(res != CURLE_OK)
 126     throw std::runtime_error("Unable to post URL");
 127
 128   std::string ret=d_data;
 129
 130   d_data.clear();
 131   return ret;
 132 }