From 2af9a7146d17e89840c2c9c4f9134c992d27361c Mon Sep 17 00:00:00 2001 From: B3n30 Date: Sat, 8 Jul 2017 16:47:24 +0200 Subject: [PATCH] Network: Handle join request in Room --- src/network/room.cpp | 200 ++++++++++++++++++++++++++++++++++++++++++- src/network/room.h | 6 ++ 2 files changed, 205 insertions(+), 1 deletion(-) diff --git a/src/network/room.cpp b/src/network/room.cpp index 274cb41590..3502264e1f 100644 --- a/src/network/room.cpp +++ b/src/network/room.cpp @@ -3,8 +3,11 @@ // Refer to the license.txt file included. #include +#include #include +#include #include "enet/enet.h" +#include "network/packet.h" #include "network/room.h" namespace Network { @@ -14,17 +17,87 @@ static constexpr u32 MaxConcurrentConnections = 10; class Room::RoomImpl { public: + // This MAC address is used to generate a 'Nintendo' like Mac address. + const MacAddress NintendoOUI = {0x00, 0x1F, 0x32, 0x00, 0x00, 0x00}; + std::mt19937 random_gen; ///< Random number generator. Used for GenerateMacAddress + ENetHost* server = nullptr; ///< Network interface. std::atomic state{State::Closed}; ///< Current state of the room. RoomInformation room_information; ///< Information about this room. + struct Member { + std::string nickname; ///< The nickname of the member. + std::string game_name; ///< The current game of the member + MacAddress mac_address; ///< The assigned mac address of the member. + ENetPeer* peer; ///< The remote peer. + }; + using MemberList = std::vector; + MemberList members; ///< Information about the members of this room. + + RoomImpl() : random_gen(std::random_device()()) {} + /// Thread that receives and dispatches network packets std::unique_ptr room_thread; /// Thread function that will receive and dispatch messages until the room is destroyed. void ServerLoop(); void StartLoop(); + + /** + * Parses and answers a room join request from a client. + * Validates the uniqueness of the username and assigns the MAC address + * that the client will use for the remainder of the connection. + */ + void HandleJoinRequest(const ENetEvent* event); + + /** + * Returns whether the nickname is valid, ie. isn't already taken by someone else in the room. + */ + bool IsValidNickname(const std::string& nickname) const; + + /** + * Returns whether the MAC address is valid, ie. isn't already taken by someone else in the + * room. + */ + bool IsValidMacAddress(const MacAddress& address) const; + + /** + * Sends a ID_ROOM_NAME_COLLISION message telling the client that the name is invalid. + */ + void SendNameCollision(ENetPeer* client); + + /** + * Sends a ID_ROOM_MAC_COLLISION message telling the client that the MAC is invalid. + */ + void SendMacCollision(ENetPeer* client); + + /** + * Notifies the member that its connection attempt was successful, + * and it is now part of the room. + */ + void SendJoinSuccess(ENetPeer* client, MacAddress mac_address); + + /** + * Sends the information about the room, along with the list of members + * to every connected client in the room. + * The packet has the structure: + * ID_ROOM_INFORMATION + * room_name + * member_slots: The max number of clients allowed in this room + * num_members: the number of currently joined clients + * This is followed by the following three values for each member: + * nickname of that member + * mac_address of that member + * game_name of that member + */ + void BroadcastRoomInformation(); + + /** + * Generates a free MAC address to assign to a new client. + * The first 3 bytes are the NintendoOUI 0x00, 0x1F, 0x32 + */ + MacAddress GenerateMacAddress(); }; // RoomImpl @@ -34,7 +107,12 @@ void Room::RoomImpl::ServerLoop() { if (enet_host_service(server, &event, 1000) > 0) { switch (event.type) { case ENET_EVENT_TYPE_RECEIVE: - // TODO(B3N30): Select the type of message and handle it + switch (event.packet->data[0]) { + case IdJoinRequest: + HandleJoinRequest(&event); + break; + // TODO(B3N30): Handle the other message types + } enet_packet_destroy(event.packet); break; case ENET_EVENT_TYPE_DISCONNECT: @@ -49,6 +127,126 @@ void Room::RoomImpl::StartLoop() { room_thread = std::make_unique(&Room::RoomImpl::ServerLoop, this); } +void Room::RoomImpl::HandleJoinRequest(const ENetEvent* event) { + Packet packet; + packet.Append(event->packet->data, event->packet->dataLength); + packet.IgnoreBytes(sizeof(MessageID)); + std::string nickname; + packet >> nickname; + + MacAddress preferred_mac; + packet >> preferred_mac; + + if (!IsValidNickname(nickname)) { + SendNameCollision(event->peer); + return; + } + + if (preferred_mac != NoPreferredMac) { + // Verify if the preferred mac is available + if (!IsValidMacAddress(preferred_mac)) { + SendMacCollision(event->peer); + return; + } + } else { + // Assign a MAC address of this client automatically + preferred_mac = GenerateMacAddress(); + } + + // At this point the client is ready to be added to the room. + Member member{}; + member.mac_address = preferred_mac; + member.nickname = nickname; + member.peer = event->peer; + + members.push_back(member); + + // Notify everyone that the room information has changed. + BroadcastRoomInformation(); + SendJoinSuccess(event->peer, preferred_mac); +} + +bool Room::RoomImpl::IsValidNickname(const std::string& nickname) const { + // A nickname is valid if it is not already taken by anybody else in the room. + // TODO(B3N30): Check for empty names, spaces, etc. + for (const Member& member : members) { + if (member.nickname == nickname) { + return false; + } + } + return true; +} + +bool Room::RoomImpl::IsValidMacAddress(const MacAddress& address) const { + // A MAC address is valid if it is not already taken by anybody else in the room. + for (const Member& member : members) { + if (member.mac_address == address) { + return false; + } + } + return true; +} + +void Room::RoomImpl::SendNameCollision(ENetPeer* client) { + Packet packet; + packet << static_cast(IdNameCollision); + + ENetPacket* enet_packet = + enet_packet_create(packet.GetData(), packet.GetDataSize(), ENET_PACKET_FLAG_RELIABLE); + enet_peer_send(client, 0, enet_packet); + enet_host_flush(server); +} + +void Room::RoomImpl::SendMacCollision(ENetPeer* client) { + Packet packet; + packet << static_cast(IdMacCollision); + + ENetPacket* enet_packet = + enet_packet_create(packet.GetData(), packet.GetDataSize(), ENET_PACKET_FLAG_RELIABLE); + enet_peer_send(client, 0, enet_packet); + enet_host_flush(server); +} + +void Room::RoomImpl::SendJoinSuccess(ENetPeer* client, MacAddress mac_address) { + Packet packet; + packet << static_cast(IdJoinSuccess); + packet << mac_address; + ENetPacket* enet_packet = + enet_packet_create(packet.GetData(), packet.GetDataSize(), ENET_PACKET_FLAG_RELIABLE); + enet_peer_send(client, 0, enet_packet); + enet_host_flush(server); +} + +void Room::RoomImpl::BroadcastRoomInformation() { + Packet packet; + packet << static_cast(IdRoomInformation); + packet << room_information.name; + packet << room_information.member_slots; + + packet << static_cast(members.size()); + for (const auto& member : members) { + packet << member.nickname; + packet << member.mac_address; + packet << member.game_name; + } + + ENetPacket* enet_packet = + enet_packet_create(packet.GetData(), packet.GetDataSize(), ENET_PACKET_FLAG_RELIABLE); + enet_host_broadcast(server, 0, enet_packet); + enet_host_flush(server); +} + +MacAddress Room::RoomImpl::GenerateMacAddress() { + MacAddress result_mac = NintendoOUI; + std::uniform_int_distribution<> dis(0x00, 0xFF); // Random byte between 0 and 0xFF + do { + for (int i = 3; i < result_mac.size(); ++i) { + result_mac[i] = dis(random_gen); + } + } while (!IsValidMacAddress(result_mac)); + return result_mac; +} + // Room Room::Room() : room_impl{std::make_unique()} {} diff --git a/src/network/room.h b/src/network/room.h index 0a6217c11e..ca663058f3 100644 --- a/src/network/room.h +++ b/src/network/room.h @@ -4,6 +4,7 @@ #pragma once +#include #include #include #include "common/common_types.h" @@ -18,6 +19,11 @@ struct RoomInformation { u32 member_slots; ///< Maximum number of members in this room }; +using MacAddress = std::array; +/// A special MAC address that tells the room we're joining to assign us a MAC address +/// automatically. +const MacAddress NoPreferredMac = {0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF}; + // The different types of messages that can be sent. The first byte of each packet defines the type typedef uint8_t MessageID; enum RoomMessageTypes {