/**************************************************************************/ /* websocket_multiplayer_peer.cpp */ /**************************************************************************/ /* This file is part of: */ /* GODOT ENGINE */ /* https://godotengine.org */ /**************************************************************************/ /* Copyright (c) 2014-present Godot Engine contributors (see AUTHORS.md). */ /* Copyright (c) 2007-2014 Juan Linietsky, Ariel Manzur. */ /* */ /* Permission is hereby granted, free of charge, to any person obtaining */ /* a copy of this software and associated documentation files (the */ /* "Software"), to deal in the Software without restriction, including */ /* without limitation the rights to use, copy, modify, merge, publish, */ /* distribute, sublicense, and/or sell copies of the Software, and to */ /* permit persons to whom the Software is furnished to do so, subject to */ /* the following conditions: */ /* */ /* The above copyright notice and this permission notice shall be */ /* included in all copies or substantial portions of the Software. */ /* */ /* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, */ /* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF */ /* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. */ /* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY */ /* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, */ /* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE */ /* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ /**************************************************************************/ #include "websocket_multiplayer_peer.h" #include "core/os/os.h" WebSocketMultiplayerPeer::WebSocketMultiplayerPeer() { _is_multiplayer = false; _peer_id = 0; _target_peer = 0; _refusing = false; _current_packet.source = 0; _current_packet.destination = 0; _current_packet.size = 0; _current_packet.data = nullptr; } WebSocketMultiplayerPeer::~WebSocketMultiplayerPeer() { _clear(); } int WebSocketMultiplayerPeer::_gen_unique_id() const { uint32_t hash = 0; while (hash == 0 || hash == 1) { hash = hash_djb2_one_32( (uint32_t)OS::get_singleton()->get_ticks_usec()); hash = hash_djb2_one_32( (uint32_t)OS::get_singleton()->get_unix_time(), hash); hash = hash_djb2_one_32( (uint32_t)OS::get_singleton()->get_data_path().hash64(), hash); hash = hash_djb2_one_32( (uint32_t)((uint64_t)this), hash); //rely on aslr heap hash = hash_djb2_one_32( (uint32_t)((uint64_t)&hash), hash); //rely on aslr stack hash = hash & 0x7FFFFFFF; // make it compatible with unsigned, since negatie id is used for exclusion } return hash; } void WebSocketMultiplayerPeer::_clear() { _peer_map.clear(); if (_current_packet.data != nullptr) { memfree(_current_packet.data); } for (List::Element *E = _incoming_packets.front(); E; E = E->next()) { memfree(E->get().data); E->get().data = nullptr; } _incoming_packets.clear(); } void WebSocketMultiplayerPeer::_bind_methods() { ClassDB::bind_method(D_METHOD("set_buffers", "input_buffer_size_kb", "input_max_packets", "output_buffer_size_kb", "output_max_packets"), &WebSocketMultiplayerPeer::set_buffers); ClassDB::bind_method(D_METHOD("get_peer", "peer_id"), &WebSocketMultiplayerPeer::get_peer); ADD_SIGNAL(MethodInfo("peer_packet", PropertyInfo(Variant::INT, "peer_source"))); } // // PacketPeer // int WebSocketMultiplayerPeer::get_available_packet_count() const { ERR_FAIL_COND_V_MSG(!_is_multiplayer, 0, "Please use get_peer(ID).get_available_packet_count to get available packet count from peers when not using the MultiplayerAPI."); return _incoming_packets.size(); } Error WebSocketMultiplayerPeer::get_packet(const uint8_t **r_buffer, int &r_buffer_size) { ERR_FAIL_COND_V_MSG(!_is_multiplayer, ERR_UNCONFIGURED, "Please use get_peer(ID).get_packet/var to communicate with peers when not using the MultiplayerAPI."); r_buffer_size = 0; if (_current_packet.data != nullptr) { memfree(_current_packet.data); _current_packet.data = nullptr; } ERR_FAIL_COND_V(_incoming_packets.size() == 0, ERR_UNAVAILABLE); _current_packet = _incoming_packets.front()->get(); _incoming_packets.pop_front(); *r_buffer = _current_packet.data; r_buffer_size = _current_packet.size; return OK; } Error WebSocketMultiplayerPeer::put_packet(const uint8_t *p_buffer, int p_buffer_size) { ERR_FAIL_COND_V_MSG(!_is_multiplayer, ERR_UNCONFIGURED, "Please use get_peer(ID).put_packet/var to communicate with peers when not using the MultiplayerAPI."); PoolVector buffer = _make_pkt(SYS_NONE, get_unique_id(), _target_peer, p_buffer, p_buffer_size); if (is_server()) { return _server_relay(1, _target_peer, &(buffer.read()[0]), buffer.size()); } else { return get_peer(1)->put_packet(&(buffer.read()[0]), buffer.size()); } } // // NetworkedMultiplayerPeer // void WebSocketMultiplayerPeer::set_transfer_mode(TransferMode p_mode) { // Websocket uses TCP, reliable } NetworkedMultiplayerPeer::TransferMode WebSocketMultiplayerPeer::get_transfer_mode() const { // Websocket uses TCP, reliable return TRANSFER_MODE_RELIABLE; } void WebSocketMultiplayerPeer::set_target_peer(int p_target_peer) { _target_peer = p_target_peer; } int WebSocketMultiplayerPeer::get_packet_peer() const { ERR_FAIL_COND_V_MSG(!_is_multiplayer, 1, "This function is not available when not using the MultiplayerAPI."); ERR_FAIL_COND_V(_incoming_packets.size() == 0, 1); return _incoming_packets.front()->get().source; } int WebSocketMultiplayerPeer::get_unique_id() const { return _peer_id; } void WebSocketMultiplayerPeer::set_refuse_new_connections(bool p_enable) { _refusing = p_enable; } bool WebSocketMultiplayerPeer::is_refusing_new_connections() const { return _refusing; } void WebSocketMultiplayerPeer::_send_sys(Ref p_peer, uint8_t p_type, int32_t p_peer_id) { ERR_FAIL_COND(!p_peer.is_valid()); ERR_FAIL_COND(!p_peer->is_connected_to_host()); PoolVector message = _make_pkt(p_type, 1, 0, (uint8_t *)&p_peer_id, 4); p_peer->put_packet(&(message.read()[0]), message.size()); } PoolVector WebSocketMultiplayerPeer::_make_pkt(uint8_t p_type, int32_t p_from, int32_t p_to, const uint8_t *p_data, uint32_t p_data_size) { PoolVector out; out.resize(PROTO_SIZE + p_data_size); PoolVector::Write w = out.write(); memcpy(&w[0], &p_type, 1); memcpy(&w[1], &p_from, 4); memcpy(&w[5], &p_to, 4); memcpy(&w[PROTO_SIZE], p_data, p_data_size); return out; } void WebSocketMultiplayerPeer::_send_add(int32_t p_peer_id) { // First of all, confirm the ID! _send_sys(get_peer(p_peer_id), SYS_ID, p_peer_id); // Then send the server peer (which will trigger connection_succeded in client) _send_sys(get_peer(p_peer_id), SYS_ADD, 1); for (Map>::Element *E = _peer_map.front(); E; E = E->next()) { int32_t id = E->key(); if (p_peer_id == id) { continue; // Skip the newwly added peer (already confirmed) } // Send new peer to others _send_sys(get_peer(id), SYS_ADD, p_peer_id); // Send others to new peer _send_sys(get_peer(p_peer_id), SYS_ADD, id); } } void WebSocketMultiplayerPeer::_send_del(int32_t p_peer_id) { for (Map>::Element *E = _peer_map.front(); E; E = E->next()) { int32_t id = E->key(); if (p_peer_id != id) { _send_sys(get_peer(id), SYS_DEL, p_peer_id); } } } void WebSocketMultiplayerPeer::_store_pkt(int32_t p_source, int32_t p_dest, const uint8_t *p_data, uint32_t p_data_size) { Packet packet; packet.data = (uint8_t *)memalloc(p_data_size); packet.size = p_data_size; packet.source = p_source; packet.destination = p_dest; memcpy(packet.data, &p_data[PROTO_SIZE], p_data_size); _incoming_packets.push_back(packet); emit_signal("peer_packet", p_source); } Error WebSocketMultiplayerPeer::_server_relay(int32_t p_from, int32_t p_to, const uint8_t *p_buffer, uint32_t p_buffer_size) { if (p_to == 1) { return OK; // Will not send to self } else if (p_to == 0) { for (Map>::Element *E = _peer_map.front(); E; E = E->next()) { if (E->key() != p_from) { E->get()->put_packet(p_buffer, p_buffer_size); } } return OK; // Sent to all but sender } else if (p_to < 0) { for (Map>::Element *E = _peer_map.front(); E; E = E->next()) { if (E->key() != p_from && E->key() != -p_to) { E->get()->put_packet(p_buffer, p_buffer_size); } } return OK; // Sent to all but sender and excluded } else { ERR_FAIL_COND_V(p_to == p_from, FAILED); Ref peer_to = get_peer(p_to); ERR_FAIL_COND_V(peer_to.is_null(), FAILED); return peer_to->put_packet(p_buffer, p_buffer_size); // Sending to specific peer } } void WebSocketMultiplayerPeer::_process_multiplayer(Ref p_peer, uint32_t p_peer_id) { ERR_FAIL_COND(!p_peer.is_valid()); const uint8_t *in_buffer; int size = 0; int data_size = 0; Error err = p_peer->get_packet(&in_buffer, size); ERR_FAIL_COND(err != OK); ERR_FAIL_COND(size < PROTO_SIZE); data_size = size - PROTO_SIZE; uint8_t type = 0; uint32_t from = 0; int32_t to = 0; memcpy(&type, in_buffer, 1); memcpy(&from, &in_buffer[1], 4); memcpy(&to, &in_buffer[5], 4); if (is_server()) { // Server can resend ERR_FAIL_COND(type != SYS_NONE); // Only server sends sys messages ERR_FAIL_COND(from != p_peer_id); // Someone is cheating if (to == 1) { // This is for the server _store_pkt(from, to, in_buffer, data_size); } else if (to == 0) { // Broadcast, for us too _store_pkt(from, to, in_buffer, data_size); } else if (to < 0) { // All but one, for us if not excluded if (_peer_id != -(int32_t)p_peer_id) { _store_pkt(from, to, in_buffer, data_size); } } // Relay if needed (i.e. "to" includes a peer that is not the server) _server_relay(from, to, in_buffer, size); } else { if (type == SYS_NONE) { // Payload message _store_pkt(from, to, in_buffer, data_size); return; } // System message ERR_FAIL_COND(data_size < 4); int id = 0; memcpy(&id, &in_buffer[PROTO_SIZE], 4); switch (type) { case SYS_ADD: // Add peer _peer_map[id] = Ref(); emit_signal("peer_connected", id); if (id == 1) { // We just connected to the server emit_signal("connection_succeeded"); } break; case SYS_DEL: // Remove peer _peer_map.erase(id); emit_signal("peer_disconnected", id); break; case SYS_ID: // Helo, server assigned ID _peer_id = id; break; default: ERR_FAIL_MSG("Invalid multiplayer message."); break; } } }