void on_read(lt::error_code const& ec, std::size_t bytes_transferred)
{
if (ec) return;
using libtorrent::entry;
using libtorrent::bdecode;
int pos;
error_code err;
// since the simulation is single threaded, we can get away with just
// allocating a single of these
static bdecode_node msg;
int ret = bdecode(m_buffer, m_buffer + bytes_transferred, msg, err, &pos, 10, 500);
if (ret != 0) return;
if (msg.type() != bdecode_node::dict_t) return;
libtorrent::dht::msg m(msg, m_ep);
dht().incoming(m);
sock().async_receive_from(asio::mutable_buffers_1(m_buffer, sizeof(m_buffer))
, m_ep, [&](lt::error_code const& ec, std::size_t bytes_transferred)
{ this->on_read(ec, bytes_transferred); });
}
// translate bittorrent kademlia message into the generice kademlia message
// used by the library
void dht_tracker::on_receive(error_code const& error, size_t bytes_transferred)
try
{
if (error == asio::error::operation_aborted) return;
if (!m_socket.is_open()) return;
int current_buffer = m_buffer;
m_buffer = (m_buffer + 1) & 1;
m_socket.async_receive_from(asio::buffer(&m_in_buf[m_buffer][0]
, m_in_buf[m_buffer].size()), m_remote_endpoint[m_buffer]
, m_strand.wrap(bind(&dht_tracker::on_receive, self(), _1, _2)));
if (error) return;
node_ban_entry* match = 0;
node_ban_entry* min = m_ban_nodes;
ptime now = time_now();
for (node_ban_entry* i = m_ban_nodes; i < m_ban_nodes + num_ban_nodes; ++i)
{
if (i->src == m_remote_endpoint[current_buffer])
{
match = i;
break;
}
if (i->count < min->count) min = i;
}
if (match)
{
++match->count;
if (match->count >= 20)
{
if (now < match->limit)
{
#ifdef TORRENT_DHT_VERBOSE_LOGGING
if (match->count == 20)
{
TORRENT_LOG(dht_tracker) << time_now_string() << " BANNING PEER [ ip: "
<< m_remote_endpoint[current_buffer] << " | "
"time: " << total_seconds((now - match->limit) + seconds(5))
<< " | count: " << match->count << " ]";
}
#endif
// we've received 20 messages in less than 5 seconds from
// this node. Ignore it until it's silent for 5 minutes
match->limit = now + minutes(5);
return;
}
// we got 50 messages from this peer, but it was in
// more than 5 seconds. Reset the counter and the timer
match->count = 0;
match->limit = now + seconds(5);
}
}
else
{
min->count = 1;
min->limit = now + seconds(5);
min->src = m_remote_endpoint[current_buffer];
}
#ifdef TORRENT_DHT_VERBOSE_LOGGING
++m_total_message_input;
m_total_in_bytes += bytes_transferred;
#endif
try
{
using libtorrent::entry;
using libtorrent::bdecode;
TORRENT_ASSERT(bytes_transferred > 0);
entry e = bdecode(m_in_buf[current_buffer].begin()
, m_in_buf[current_buffer].end());
#ifdef TORRENT_DHT_VERBOSE_LOGGING
TORRENT_LOG(dht_tracker) << time_now_string() << " RECEIVED ["
<< m_remote_endpoint[current_buffer] << "]:";
#endif
libtorrent::dht::msg m;
m.message_id = 0;
m.addr = m_remote_endpoint[current_buffer];
m.transaction_id = e["t"].string();
#ifdef TORRENT_DHT_VERBOSE_LOGGING
try
{
entry const* ver = e.find_key("v");
if (!ver) throw std::exception();
std::string const& client = ver->string();
if (client.size() > 1 && std::equal(client.begin(), client.begin() + 2, "UT"))
{
++m_ut_message_input;
TORRENT_LOG(dht_tracker) << " client: uTorrent";
}
else if (client.size() > 1 && std::equal(client.begin(), client.begin() + 2, "LT"))
{
++m_lt_message_input;
TORRENT_LOG(dht_tracker) << " client: libtorrent";
}
else if (client.size() > 1 && std::equal(client.begin(), client.begin() + 2, "MP"))
{
++m_mp_message_input;
TORRENT_LOG(dht_tracker) << " client: MooPolice";
}
else if (client.size() > 1 && std::equal(client.begin(), client.begin() + 2, "GR"))
{
++m_gr_message_input;
TORRENT_LOG(dht_tracker) << " client: GetRight";
}
else if (client.size() > 1 && std::equal(client.begin(), client.begin() + 2, "MO"))
{
++m_mo_message_input;
TORRENT_LOG(dht_tracker) << " client: Mono Torrent";
}
else
{
TORRENT_LOG(dht_tracker) << " client: " << client;
}
}
catch (std::exception&)
{
TORRENT_LOG(dht_tracker) << " client: generic";
};
#endif
std::string const& msg_type = e["y"].string();
if (msg_type == "r")
{
#ifdef TORRENT_DHT_VERBOSE_LOGGING
TORRENT_LOG(dht_tracker) << " reply: transaction: "
<< m.transaction_id;
#endif
m.reply = true;
entry const& r = e["r"];
std::string const& id = r["id"].string();
if (id.size() != 20) throw std::runtime_error("invalid size of id");
std::copy(id.begin(), id.end(), m.id.begin());
if (entry const* n = r.find_key("values"))
{
m.peers.clear();
if (n->list().size() == 1)
{
// assume it's mainline format
std::string const& peers = n->list().front().string();
std::string::const_iterator i = peers.begin();
std::string::const_iterator end = peers.end();
while (std::distance(i, end) >= 6)
m.peers.push_back(read_v4_endpoint<tcp::endpoint>(i));
}
else
{
// assume it's uTorrent/libtorrent format
read_endpoint_list<tcp::endpoint>(n, m.peers);
}
#ifdef TORRENT_DHT_VERBOSE_LOGGING
TORRENT_LOG(dht_tracker) << " peers: " << m.peers.size();
#endif
}
m.nodes.clear();
if (entry const* n = r.find_key("nodes"))
{
std::string const& nodes = n->string();
std::string::const_iterator i = nodes.begin();
std::string::const_iterator end = nodes.end();
while (std::distance(i, end) >= 26)
{
node_id id;
std::copy(i, i + 20, id.begin());
i += 20;
m.nodes.push_back(libtorrent::dht::node_entry(
id, read_v4_endpoint<udp::endpoint>(i)));
}
#ifdef TORRENT_DHT_VERBOSE_LOGGING
TORRENT_LOG(dht_tracker) << " nodes: " << m.nodes.size();
#endif
}
if (entry const* n = r.find_key("nodes2"))
{
entry::list_type const& contacts = n->list();
for (entry::list_type::const_iterator i = contacts.begin()
, end(contacts.end()); i != end; ++i)
{
std::string const& p = i->string();
if (p.size() < 6 + 20) continue;
std::string::const_iterator in = p.begin();
node_id id;
std::copy(in, in + 20, id.begin());
in += 20;
if (p.size() == 6 + 20)
m.nodes.push_back(libtorrent::dht::node_entry(
id, read_v4_endpoint<udp::endpoint>(in)));
else if (p.size() == 18 + 20)
m.nodes.push_back(libtorrent::dht::node_entry(
id, read_v6_endpoint<udp::endpoint>(in)));
}
#ifdef TORRENT_DHT_VERBOSE_LOGGING
TORRENT_LOG(dht_tracker) << " nodes2 + nodes: " << m.nodes.size();
#endif
}
entry const* token = r.find_key("token");
if (token) m.write_token = *token;
}
else if (msg_type == "q")
{
m.reply = false;
entry const& a = e["a"];
std::string const& id = a["id"].string();
if (id.size() != 20) throw std::runtime_error("invalid size of id");
std::copy(id.begin(), id.end(), m.id.begin());
std::string request_kind(e["q"].string());
#ifdef TORRENT_DHT_VERBOSE_LOGGING
TORRENT_LOG(dht_tracker) << " query: " << request_kind;
#endif
if (request_kind == "ping")
{
m.message_id = libtorrent::dht::messages::ping;
}
else if (request_kind == "find_node")
{
std::string const& target = a["target"].string();
if (target.size() != 20) throw std::runtime_error("invalid size of target id");
std::copy(target.begin(), target.end(), m.info_hash.begin());
#ifdef TORRENT_DHT_VERBOSE_LOGGING
TORRENT_LOG(dht_tracker) << " target: "
<< boost::lexical_cast<std::string>(m.info_hash);
#endif
m.message_id = libtorrent::dht::messages::find_node;
}
else if (request_kind == "get_peers")
{
std::string const& info_hash = a["info_hash"].string();
if (info_hash.size() != 20) throw std::runtime_error("invalid size of info-hash");
std::copy(info_hash.begin(), info_hash.end(), m.info_hash.begin());
m.message_id = libtorrent::dht::messages::get_peers;
#ifdef TORRENT_DHT_VERBOSE_LOGGING
TORRENT_LOG(dht_tracker) << " info_hash: "
<< boost::lexical_cast<std::string>(m.info_hash);
#endif
}
else if (request_kind == "announce_peer")
{
#ifdef TORRENT_DHT_VERBOSE_LOGGING
++m_announces;
#endif
std::string const& info_hash = a["info_hash"].string();
if (info_hash.size() != 20)
throw std::runtime_error("invalid size of info-hash");
std::copy(info_hash.begin(), info_hash.end(), m.info_hash.begin());
m.port = a["port"].integer();
m.write_token = a["token"];
m.message_id = libtorrent::dht::messages::announce_peer;
#ifdef TORRENT_DHT_VERBOSE_LOGGING
TORRENT_LOG(dht_tracker) << " info_hash: "
<< boost::lexical_cast<std::string>(m.info_hash);
TORRENT_LOG(dht_tracker) << " port: " << m.port;
if (!m_dht.verify_token(m))
++m_failed_announces;
#endif
}
else
{
#ifdef TORRENT_DHT_VERBOSE_LOGGING
TORRENT_LOG(dht_tracker) << " *** UNSUPPORTED REQUEST *** : "
<< request_kind;
#endif
throw std::runtime_error("unsupported request: " + request_kind);
}
}
else if (msg_type == "e")
{
entry::list_type const& list = e["e"].list();
m.message_id = messages::error;
m.error_msg = list.back().string();
m.error_code = list.front().integer();
#ifdef TORRENT_DHT_VERBOSE_LOGGING
TORRENT_LOG(dht_tracker) << " incoming error: " << m.error_code << " "
<< m.error_msg;
#endif
throw std::runtime_error("DHT error message");
}
else
{
#ifdef TORRENT_DHT_VERBOSE_LOGGING
TORRENT_LOG(dht_tracker) << " *** UNSUPPORTED MESSAGE TYPE *** : "
<< msg_type;
#endif
throw std::runtime_error("unsupported message type: " + msg_type);
}
#ifdef TORRENT_DHT_VERBOSE_LOGGING
if (!m.reply)
{
++m_queries_received[m.message_id];
m_queries_bytes_received[m.message_id] += int(bytes_transferred);
}
TORRENT_LOG(dht_tracker) << e;
#endif
TORRENT_ASSERT(m.message_id != messages::error);
m_dht.incoming(m);
}
catch (std::exception& e)
{
#ifdef TORRENT_DHT_VERBOSE_LOGGING
int current_buffer = (m_buffer + 1) & 1;
std::string msg(m_in_buf[current_buffer].begin()
, m_in_buf[current_buffer].begin() + bytes_transferred);
TORRENT_LOG(dht_tracker) << "invalid incoming packet: "
<< e.what() << "\n" << msg << "\n";
#endif
}
}
catch (std::exception& e)
{
TORRENT_ASSERT(false);
};