/* Copyright (c) 2007-2012, Arvid Norberg 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 author 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 OR CONTRIBUTORS 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 "libtorrent/pch.hpp" #include "libtorrent/lsd.hpp" #include "libtorrent/io.hpp" #include "libtorrent/http_tracker_connection.hpp" #include "libtorrent/buffer.hpp" #include "libtorrent/random.hpp" #include "libtorrent/http_parser.hpp" #include "libtorrent/escape_string.hpp" #include "libtorrent/socket_io.hpp" // for print_address #if defined TORRENT_ASIO_DEBUGGING #include "libtorrent/debug.hpp" #endif #include #include #if BOOST_VERSION < 103500 #include #include #else #include #include #endif #include #include using namespace libtorrent; namespace libtorrent { // defined in broadcast_socket.cpp address guess_local_address(io_service&); } static error_code ec; lsd::lsd(io_service& ios, address const& listen_interface , peer_callback_t const& cb) : m_callback(cb) , m_socket(udp::endpoint(address_v4::from_string("239.192.152.143", ec), 6771) , boost::bind(&lsd::on_announce, self(), _1, _2, _3)) , m_broadcast_timer(ios) , m_retry_count(1) , m_cookie(random()) , m_disabled(false) { #if defined(TORRENT_LOGGING) || defined(TORRENT_VERBOSE_LOGGING) m_log = fopen("lsd.log", "w+"); if (m_log == NULL) { fprintf(stderr, "failed to open 'lsd.log': (%d) %s" , errno, strerror(errno)); } #endif error_code ec; m_socket.open(ios, ec); #if defined(TORRENT_LOGGING) || defined(TORRENT_VERBOSE_LOGGING) if (ec) { if (m_log) fprintf(m_log, "FAILED TO OPEN SOCKET: (%d) %s\n" , ec.value(), ec.message().c_str()); } #endif } lsd::~lsd() { #if defined(TORRENT_LOGGING) || defined(TORRENT_VERBOSE_LOGGING) if (m_log) fclose(m_log); #endif } void lsd::announce(sha1_hash const& ih, int listen_port, bool broadcast) { if (m_disabled) return; char ih_hex[41]; to_hex((char const*)&ih[0], 20, ih_hex); char msg[200]; int msg_len = snprintf(msg, sizeof(msg), "BT-SEARCH * HTTP/1.1\r\n" "Host: 239.192.152.143:6771\r\n" "Port: %d\r\n" "Infohash: %s\r\n" "cookie: %x\r\n" "\r\n\r\n", listen_port, ih_hex, m_cookie); #if defined(TORRENT_LOGGING) || defined(TORRENT_VERBOSE_LOGGING) { if (m_log) fprintf(m_log, "%s ==> announce: ih: %s port: %u\n" , time_now_string(), ih_hex, listen_port); } #endif m_retry_count = 1; error_code ec; m_socket.send(msg, msg_len, ec, broadcast ? broadcast_socket::broadcast : 0); if (ec) { m_disabled = true; #if defined(TORRENT_LOGGING) || defined(TORRENT_VERBOSE_LOGGING) { if (m_log) fprintf(m_log, "%s failed to send message: (%d) %s" , time_now_string(), ec.value(), ec.message().c_str()); } #endif return; } #if defined TORRENT_ASIO_DEBUGGING add_outstanding_async("lsd::resend_announce"); #endif m_broadcast_timer.expires_from_now(seconds(2 * m_retry_count), ec); m_broadcast_timer.async_wait(boost::bind(&lsd::resend_announce, self(), _1 , std::string(msg))); } void lsd::resend_announce(error_code const& e, std::string msg) { #if defined TORRENT_ASIO_DEBUGGING complete_async("lsd::resend_announce"); #endif if (e) return; error_code ec; m_socket.send(msg.c_str(), int(msg.size()), ec); ++m_retry_count; if (m_retry_count >= 3) return; #if defined TORRENT_ASIO_DEBUGGING add_outstanding_async("lsd::resend_announce"); #endif m_broadcast_timer.expires_from_now(seconds(2 * m_retry_count), ec); m_broadcast_timer.async_wait(boost::bind(&lsd::resend_announce, self(), _1, msg)); } void lsd::on_announce(udp::endpoint const& from, char* buffer , std::size_t bytes_transferred) { using namespace libtorrent::detail; http_parser p; bool error = false; p.incoming(buffer::const_interval(buffer, buffer + bytes_transferred) , error); if (!p.header_finished() || error) { #if defined(TORRENT_LOGGING) || defined(TORRENT_VERBOSE_LOGGING) if (m_log) fprintf(m_log, "%s <== announce: incomplete HTTP message\n", time_now_string()); #endif return; } if (p.method() != "bt-search") { #if defined(TORRENT_LOGGING) || defined(TORRENT_VERBOSE_LOGGING) if (m_log) fprintf(m_log, "%s <== announce: invalid HTTP method: %s\n" , time_now_string(), p.method().c_str()); #endif return; } std::string const& port_str = p.header("port"); if (port_str.empty()) { #if defined(TORRENT_LOGGING) || defined(TORRENT_VERBOSE_LOGGING) if (m_log) fprintf(m_log, "%s <== announce: invalid BT-SEARCH, missing port\n" , time_now_string()); #endif return; } int port = std::atoi(port_str.c_str()); typedef std::multimap headers_t; headers_t const& headers = p.headers(); headers_t::const_iterator cookie_iter = headers.find("cookie"); if (cookie_iter != headers.end()) { // we expect it to be hexadecimal // if it isn't, it's not our cookie anyway boost::uint32_t cookie = strtol(cookie_iter->second.c_str(), NULL, 16); if (cookie == m_cookie) { #if defined(TORRENT_LOGGING) || defined(TORRENT_VERBOSE_LOGGING) if (m_log) fprintf(m_log, "%s <== announce: ignoring packet (cookie matched our own): %x == %x\n" , time_now_string(), cookie, m_cookie); #endif return; } } std::pair ihs = headers.equal_range("infohash"); for (headers_t::const_iterator i = ihs.first; i != ihs.second; ++i) { std::string const& ih_str = i->second; if (ih_str.size() != 40) { #if defined(TORRENT_LOGGING) || defined(TORRENT_VERBOSE_LOGGING) if (m_log) fprintf(m_log, "%s <== announce: invalid BT-SEARCH, invalid infohash: %s\n" , time_now_string(), ih_str.c_str()); #endif continue; } sha1_hash ih(0); from_hex(ih_str.c_str(), 40, (char*)&ih[0]); if (!ih.is_all_zeros() && port != 0) { #if defined(TORRENT_LOGGING) || defined(TORRENT_VERBOSE_LOGGING) if (m_log) fprintf(m_log, "%s *** incoming local announce %s:%d ih: %s\n" , time_now_string(), print_address(from.address()).c_str() , port, ih_str.c_str()); #endif // we got an announce, pass it on through the callback TORRENT_TRY { m_callback(tcp::endpoint(from.address(), port), ih); } TORRENT_CATCH(std::exception&) {} } } } void lsd::close() { m_socket.close(); error_code ec; m_broadcast_timer.cancel(ec); m_disabled = true; m_callback.clear(); }