/* Copyright (c) 2007-2016, 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 #include "libtorrent/config.hpp" #include "libtorrent/aux_/disable_warnings_push.hpp" #if defined TORRENT_OS2 #include #endif #include #include #include #ifdef TORRENT_WINDOWS #include // for if_nametoindex #endif #include "libtorrent/aux_/disable_warnings_pop.hpp" #include "libtorrent/socket.hpp" #include "libtorrent/enum_net.hpp" #include "libtorrent/broadcast_socket.hpp" #include "libtorrent/assert.hpp" #include "libtorrent/debug.hpp" #ifdef TORRENT_DEBUG #include "libtorrent/socket_io.hpp" #endif namespace libtorrent { bool is_ip_address(char const* host) { error_code ec; address::from_string(host, ec); return !ec; } bool is_local(address const& a) { TORRENT_TRY { #if TORRENT_USE_IPV6 if (a.is_v6()) { return a.to_v6().is_loopback() || a.to_v6().is_link_local() || a.to_v6().is_multicast_link_local(); } #endif address_v4 a4 = a.to_v4(); unsigned long ip = a4.to_ulong(); return ((ip & 0xff000000) == 0x0a000000 // 10.x.x.x || (ip & 0xfff00000) == 0xac100000 // 172.16.x.x || (ip & 0xffff0000) == 0xc0a80000 // 192.168.x.x || (ip & 0xffff0000) == 0xa9fe0000 // 169.254.x.x || (ip & 0xff000000) == 0x7f000000); // 127.x.x.x } TORRENT_CATCH(std::exception&) { return false; } } bool is_loopback(address const& addr) { #if TORRENT_USE_IPV6 TORRENT_TRY { if (addr.is_v4()) return addr.to_v4() == address_v4::loopback(); else return addr.to_v6() == address_v6::loopback(); } TORRENT_CATCH(std::exception&) { return false; } #else return addr.to_v4() == address_v4::loopback(); #endif } bool is_any(address const& addr) { TORRENT_TRY { #if TORRENT_USE_IPV6 if (addr.is_v4()) return addr.to_v4() == address_v4::any(); else if (addr.to_v6().is_v4_mapped()) return (addr.to_v6().to_v4() == address_v4::any()); else return addr.to_v6() == address_v6::any(); #else return addr.to_v4() == address_v4::any(); #endif } TORRENT_CATCH(std::exception&) { return false; } } bool is_teredo(address const& addr) { #if TORRENT_USE_IPV6 TORRENT_TRY { if (!addr.is_v6()) return false; boost::uint8_t teredo_prefix[] = {0x20, 0x01, 0, 0}; address_v6::bytes_type b = addr.to_v6().to_bytes(); return memcmp(&b[0], teredo_prefix, 4) == 0; } TORRENT_CATCH(std::exception&) { return false; } #else TORRENT_UNUSED(addr); return false; #endif } bool supports_ipv6() { #if !TORRENT_USE_IPV6 return false; #elif defined TORRENT_BUILD_SIMULATOR return true; #elif defined TORRENT_WINDOWS TORRENT_TRY { error_code ec; address::from_string("::1", ec); return !ec; } TORRENT_CATCH(std::exception&) { return false; } #else io_service ios; tcp::socket test(ios); error_code ec; test.open(tcp::v6(), ec); return !bool(ec); #endif } broadcast_socket::broadcast_socket( udp::endpoint const& multicast_endpoint) : m_multicast_endpoint(multicast_endpoint) , m_outstanding_operations(0) , m_abort(false) { TORRENT_ASSERT(m_multicast_endpoint.address().is_multicast()); } void broadcast_socket::open(receive_handler_t const& handler , io_service& ios, error_code& ec, bool loopback) { m_on_receive = handler; std::vector interfaces = enum_net_interfaces(ios, ec); #if TORRENT_USE_IPV6 if (m_multicast_endpoint.address().is_v6()) open_multicast_socket(ios, address_v6::any(), loopback, ec); else #endif open_multicast_socket(ios, address_v4::any(), loopback, ec); for (std::vector::const_iterator i = interfaces.begin() , end(interfaces.end()); i != end; ++i) { // only multicast on compatible networks if (i->interface_address.is_v4() != m_multicast_endpoint.address().is_v4()) continue; // ignore any loopback interface if (!loopback && is_loopback(i->interface_address)) continue; ec = error_code(); // if_nametoindex was introduced in vista #if TORRENT_USE_IPV6 \ && (!defined TORRENT_WINDOWS || _WIN32_WINNT >= 0x0600) \ && !defined TORRENT_MINGW if (i->interface_address.is_v6() && i->interface_address.to_v6().is_link_local()) { address_v6 addr6 = i->interface_address.to_v6(); addr6.scope_id(if_nametoindex(i->name)); open_multicast_socket(ios, addr6, loopback, ec); address_v4 const& mask = i->netmask.is_v4() ? i->netmask.to_v4() : address_v4(); open_unicast_socket(ios, addr6, mask); continue; } #endif open_multicast_socket(ios, i->interface_address, loopback, ec); #ifdef TORRENT_DEBUG std::fprintf(stderr, "broadcast socket [ if: %s group: %s mask: %s ] %s\n" , i->interface_address.to_string().c_str() , m_multicast_endpoint.address().to_string().c_str() , i->netmask.to_string().c_str() , ec.message().c_str()); #endif open_unicast_socket(ios, i->interface_address , i->netmask.is_v4() ? i->netmask.to_v4() : address_v4()); } } void broadcast_socket::open_multicast_socket(io_service& ios , address const& addr, bool loopback, error_code& ec) { using namespace boost::asio::ip::multicast; boost::shared_ptr s(new udp::socket(ios)); s->open(addr.is_v4() ? udp::v4() : udp::v6(), ec); if (ec) return; s->set_option(udp::socket::reuse_address(true), ec); if (ec) return; s->bind(udp::endpoint(addr, m_multicast_endpoint.port()), ec); if (ec) return; s->set_option(join_group(m_multicast_endpoint.address()), ec); if (ec) return; s->set_option(hops(255), ec); if (ec) return; s->set_option(enable_loopback(loopback), ec); if (ec) return; m_sockets.push_back(socket_entry(s)); socket_entry& se = m_sockets.back(); ADD_OUTSTANDING_ASYNC("broadcast_socket::on_receive"); s->async_receive_from(boost::asio::buffer(se.buffer, sizeof(se.buffer)) , se.remote, boost::bind(&broadcast_socket::on_receive, this, &se, _1, _2)); ++m_outstanding_operations; } void broadcast_socket::open_unicast_socket(io_service& ios, address const& addr , address_v4 const& mask) { error_code ec; boost::shared_ptr s(new udp::socket(ios)); s->open(addr.is_v4() ? udp::v4() : udp::v6(), ec); if (ec) return; s->bind(udp::endpoint(addr, 0), ec); if (ec) return; m_unicast_sockets.push_back(socket_entry(s, mask)); socket_entry& se = m_unicast_sockets.back(); // allow sending broadcast messages boost::asio::socket_base::broadcast option(true); s->set_option(option, ec); if (!ec) se.broadcast = true; ADD_OUTSTANDING_ASYNC("broadcast_socket::on_receive"); s->async_receive_from(boost::asio::buffer(se.buffer, sizeof(se.buffer)) , se.remote, boost::bind(&broadcast_socket::on_receive, this, &se, _1, _2)); ++m_outstanding_operations; } void broadcast_socket::send(char const* buffer, int size, error_code& ec, int flags) { bool all_fail = true; error_code e; for (std::list::iterator i = m_unicast_sockets.begin() , end(m_unicast_sockets.end()); i != end; ++i) { if (!i->socket) continue; i->socket->send_to(boost::asio::buffer(buffer, size), m_multicast_endpoint, 0, e); // if the user specified the broadcast flag, send one to the broadcast // address as well if ((flags & broadcast_socket::broadcast) && i->can_broadcast()) i->socket->send_to(boost::asio::buffer(buffer, size) , udp::endpoint(i->broadcast_address(), m_multicast_endpoint.port()), 0, e); if (e) { i->socket->close(e); i->socket.reset(); } else { all_fail = false; } } for (std::list::iterator i = m_sockets.begin() , end(m_sockets.end()); i != end; ++i) { if (!i->socket) continue; i->socket->send_to(boost::asio::buffer(buffer, size), m_multicast_endpoint, 0, e); if (e) { i->socket->close(e); i->socket.reset(); } else { all_fail = false; } } if (all_fail) ec = e; } void broadcast_socket::on_receive(socket_entry* s, error_code const& ec , std::size_t bytes_transferred) { COMPLETE_ASYNC("broadcast_socket::on_receive"); TORRENT_ASSERT(m_outstanding_operations > 0); --m_outstanding_operations; if (ec || bytes_transferred == 0 || !m_on_receive) { maybe_abort(); return; } m_on_receive(s->remote, s->buffer, int(bytes_transferred)); if (maybe_abort()) return; if (!s->socket) return; ADD_OUTSTANDING_ASYNC("broadcast_socket::on_receive"); s->socket->async_receive_from(boost::asio::buffer(s->buffer, sizeof(s->buffer)) , s->remote, boost::bind(&broadcast_socket::on_receive, this, s, _1, _2)); ++m_outstanding_operations; } bool broadcast_socket::maybe_abort() { bool ret = m_abort; if (m_abort && m_outstanding_operations == 0) { // it's important that m_on_receive is cleared // before the object is destructed, since it may // hold a reference to ourself, which would otherwise // cause an infinite recursion destructing the objects receive_handler_t().swap(m_on_receive); } return ret; } void broadcast_socket::close() { std::for_each(m_sockets.begin(), m_sockets.end(), boost::bind(&socket_entry::close, _1)); std::for_each(m_unicast_sockets.begin(), m_unicast_sockets.end(), boost::bind(&socket_entry::close, _1)); m_abort = true; maybe_abort(); } }