pdns/dnsdist-dynbpf.cc

   1 /*
   2  * This file is part of PowerDNS or dnsdist.
   3  * Copyright -- PowerDNS.COM B.V. and its contributors
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of version 2 of the GNU General Public License as
   7  * published by the Free Software Foundation.
   8  *
   9  * In addition, for the avoidance of any doubt, permission is granted to
  10  * link this program with OpenSSL and to (re)distribute the binaries
  11  * produced as the result of such linking.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  21  */
  22 #include "dnsdist-dynbpf.hh"
  23
  24 bool DynBPFFilter::block(const ComboAddress& addr, const struct timespec& until)
  25 {
  26   bool inserted = false;
  27   auto data = d_data.lock();
  28
  29   if (data->d_excludedSubnets.match(addr)) {
  30     /* do not add a block for excluded subnets */
  31     return inserted;
  32   }
  33
  34   const container_t::iterator it = data->d_entries.find(addr);
  35   if (it != data->d_entries.end()) {
  36     if (it->d_until < until) {
  37       data->d_entries.replace(it, BlockEntry(addr, until));
  38     }
  39   }
  40   else {
  41     data->d_bpf->block(addr, BPFFilter::MatchAction::Drop);
  42     data->d_entries.insert(BlockEntry(addr, until));
  43     inserted = true;
  44   }
  45   return inserted;
  46 }
  47
  48 void DynBPFFilter::purgeExpired(const struct timespec& now)
  49 {
  50   auto data = d_data.lock();
  51
  52   typedef boost::multi_index::nth_index<container_t,1>::type ordered_until;
  53   ordered_until& ou = boost::multi_index::get<1>(data->d_entries);
  54
  55   for (ordered_until::iterator it = ou.begin(); it != ou.end(); ) {
  56     if (it->d_until < now) {
  57       ComboAddress addr = it->d_addr;
  58       it = ou.erase(it);
  59       data->d_bpf->unblock(addr);
  60     }
  61     else {
  62       break;
  63     }
  64   }
  65 }
  66
  67 std::vector<std::tuple<ComboAddress, uint64_t, struct timespec> > DynBPFFilter::getAddrStats()
  68 {
  69   std::vector<std::tuple<ComboAddress, uint64_t, struct timespec> > result;
  70   auto data = d_data.lock();
  71
  72   if (!data->d_bpf) {
  73     return result;
  74   }
  75
  76   const auto& stats = data->d_bpf->getAddrStats();
  77   result.reserve(stats.size());
  78   for (const auto& stat : stats) {
  79     const container_t::iterator it = data->d_entries.find(stat.first);
  80     if (it != data->d_entries.end()) {
  81       result.push_back(std::make_tuple(stat.first, stat.second, it->d_until));
  82     }
  83   }
  84   return result;
  85 }