network: Add initial files and enet dependency

.gitmodules

+[submodule "enet"]
+    path = externals/enet
+    url = https://github.com/lsalzman/enet.git
 [submodule "inih"]
     path = externals/inih/inih
     url = https://github.com/benhoyt/inih.git

externals/CMakeLists.txt

@@ -73,6 +73,10 @@ if (YUZU_USE_EXTERNAL_SDL2)
     add_library(SDL2 ALIAS SDL2-static)
 endif()
 
+# ENet
+add_subdirectory(enet)
+target_include_directories(enet INTERFACE ./enet/include)
+
 # Cubeb
 if(ENABLE_CUBEB)
     set(BUILD_TESTS OFF CACHE BOOL "")

enet @ 39a72ab1

+Subproject commit 39a72ab1990014eb399cee9d538fd529df99c6a0

src/CMakeLists.txt

@@ -156,6 +156,7 @@ add_subdirectory(common)
 add_subdirectory(core)
 add_subdirectory(audio_core)
 add_subdirectory(video_core)
+add_subdirectory(network)
 add_subdirectory(input_common)
 add_subdirectory(shader_recompiler)
 

src/network/CMakeLists.txt

+add_library(network STATIC
+    network.cpp
+    network.h
+    packet.cpp
+    packet.h
+    room.cpp
+    room.h
+    room_member.cpp
+    room_member.h
+    verify_user.cpp
+    verify_user.h
+)
+
+create_target_directory_groups(network)
+
+target_link_libraries(network PRIVATE common enet Boost::boost)

src/network/network.cpp

+// Copyright 2017 Citra Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#include "common/assert.h"
+#include "common/logging/log.h"
+#include "enet/enet.h"
+#include "network/network.h"
+
+namespace Network {
+
+static std::shared_ptr<RoomMember> g_room_member; ///< RoomMember (Client) for network games
+static std::shared_ptr<Room> g_room;              ///< Room (Server) for network games
+// TODO(B3N30): Put these globals into a networking class
+
+bool Init() {
+    if (enet_initialize() != 0) {
+        LOG_ERROR(Network, "Error initalizing ENet");
+        return false;
+    }
+    g_room = std::make_shared<Room>();
+    g_room_member = std::make_shared<RoomMember>();
+    LOG_DEBUG(Network, "initialized OK");
+    return true;
+}
+
+std::weak_ptr<Room> GetRoom() {
+    return g_room;
+}
+
+std::weak_ptr<RoomMember> GetRoomMember() {
+    return g_room_member;
+}
+
+void Shutdown() {
+    if (g_room_member) {
+        if (g_room_member->IsConnected())
+            g_room_member->Leave();
+        g_room_member.reset();
+    }
+    if (g_room) {
+        if (g_room->GetState() == Room::State::Open)
+            g_room->Destroy();
+        g_room.reset();
+    }
+    enet_deinitialize();
+    LOG_DEBUG(Network, "shutdown OK");
+}
+
+} // namespace Network

src/network/network.h

+// Copyright 2017 Citra Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#pragma once
+
+#include <memory>
+#include "network/room.h"
+#include "network/room_member.h"
+
+namespace Network {
+
+/// Initializes and registers the network device, the room, and the room member.
+bool Init();
+
+/// Returns a pointer to the room handle
+std::weak_ptr<Room> GetRoom();
+
+/// Returns a pointer to the room member handle
+std::weak_ptr<RoomMember> GetRoomMember();
+
+/// Unregisters the network device, the room, and the room member and shut them down.
+void Shutdown();
+
+} // namespace Network

src/network/packet.cpp

+// Copyright 2017 Citra Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#ifdef _WIN32
+#include <winsock2.h>
+#else
+#include <arpa/inet.h>
+#endif
+#include <cstring>
+#include <string>
+#include "network/packet.h"
+
+namespace Network {
+
+#ifndef htonll
+u64 htonll(u64 x) {
+    return ((1 == htonl(1)) ? (x) : ((uint64_t)htonl((x)&0xFFFFFFFF) << 32) | htonl((x) >> 32));
+}
+#endif
+
+#ifndef ntohll
+u64 ntohll(u64 x) {
+    return ((1 == ntohl(1)) ? (x) : ((uint64_t)ntohl((x)&0xFFFFFFFF) << 32) | ntohl((x) >> 32));
+}
+#endif
+
+void Packet::Append(const void* in_data, std::size_t size_in_bytes) {
+    if (in_data && (size_in_bytes > 0)) {
+        std::size_t start = data.size();
+        data.resize(start + size_in_bytes);
+        std::memcpy(&data[start], in_data, size_in_bytes);
+    }
+}
+
+void Packet::Read(void* out_data, std::size_t size_in_bytes) {
+    if (out_data && CheckSize(size_in_bytes)) {
+        std::memcpy(out_data, &data[read_pos], size_in_bytes);
+        read_pos += size_in_bytes;
+    }
+}
+
+void Packet::Clear() {
+    data.clear();
+    read_pos = 0;
+    is_valid = true;
+}
+
+const void* Packet::GetData() const {
+    return !data.empty() ? &data[0] : nullptr;
+}
+
+void Packet::IgnoreBytes(u32 length) {
+    read_pos += length;
+}
+
+std::size_t Packet::GetDataSize() const {
+    return data.size();
+}
+
+bool Packet::EndOfPacket() const {
+    return read_pos >= data.size();
+}
+
+Packet::operator bool() const {
+    return is_valid;
+}
+
+Packet& Packet::operator>>(bool& out_data) {
+    u8 value;
+    if (*this >> value) {
+        out_data = (value != 0);
+    }
+    return *this;
+}
+
+Packet& Packet::operator>>(s8& out_data) {
+    Read(&out_data, sizeof(out_data));
+    return *this;
+}
+
+Packet& Packet::operator>>(u8& out_data) {
+    Read(&out_data, sizeof(out_data));
+    return *this;
+}
+
+Packet& Packet::operator>>(s16& out_data) {
+    s16 value;
+    Read(&value, sizeof(value));
+    out_data = ntohs(value);
+    return *this;
+}
+
+Packet& Packet::operator>>(u16& out_data) {
+    u16 value;
+    Read(&value, sizeof(value));
+    out_data = ntohs(value);
+    return *this;
+}
+
+Packet& Packet::operator>>(s32& out_data) {
+    s32 value;
+    Read(&value, sizeof(value));
+    out_data = ntohl(value);
+    return *this;
+}
+
+Packet& Packet::operator>>(u32& out_data) {
+    u32 value;
+    Read(&value, sizeof(value));
+    out_data = ntohl(value);
+    return *this;
+}
+
+Packet& Packet::operator>>(s64& out_data) {
+    s64 value;
+    Read(&value, sizeof(value));
+    out_data = ntohll(value);
+    return *this;
+}
+
+Packet& Packet::operator>>(u64& out_data) {
+    u64 value;
+    Read(&value, sizeof(value));
+    out_data = ntohll(value);
+    return *this;
+}
+
+Packet& Packet::operator>>(float& out_data) {
+    Read(&out_data, sizeof(out_data));
+    return *this;
+}
+
+Packet& Packet::operator>>(double& out_data) {
+    Read(&out_data, sizeof(out_data));
+    return *this;
+}
+
+Packet& Packet::operator>>(char* out_data) {
+    // First extract string length
+    u32 length = 0;
+    *this >> length;
+
+    if ((length > 0) && CheckSize(length)) {
+        // Then extract characters
+        std::memcpy(out_data, &data[read_pos], length);
+        out_data[length] = '\0';
+
+        // Update reading position
+        read_pos += length;
+    }
+
+    return *this;
+}
+
+Packet& Packet::operator>>(std::string& out_data) {
+    // First extract string length
+    u32 length = 0;
+    *this >> length;
+
+    out_data.clear();
+    if ((length > 0) && CheckSize(length)) {
+        // Then extract characters
+        out_data.assign(&data[read_pos], length);
+
+        // Update reading position
+        read_pos += length;
+    }
+
+    return *this;
+}
+
+Packet& Packet::operator<<(bool in_data) {
+    *this << static_cast<u8>(in_data);
+    return *this;
+}
+
+Packet& Packet::operator<<(s8 in_data) {
+    Append(&in_data, sizeof(in_data));
+    return *this;
+}
+
+Packet& Packet::operator<<(u8 in_data) {
+    Append(&in_data, sizeof(in_data));
+    return *this;
+}
+
+Packet& Packet::operator<<(s16 in_data) {
+    s16 toWrite = htons(in_data);
+    Append(&toWrite, sizeof(toWrite));
+    return *this;
+}
+
+Packet& Packet::operator<<(u16 in_data) {
+    u16 toWrite = htons(in_data);
+    Append(&toWrite, sizeof(toWrite));
+    return *this;
+}
+
+Packet& Packet::operator<<(s32 in_data) {
+    s32 toWrite = htonl(in_data);
+    Append(&toWrite, sizeof(toWrite));
+    return *this;
+}
+
+Packet& Packet::operator<<(u32 in_data) {
+    u32 toWrite = htonl(in_data);
+    Append(&toWrite, sizeof(toWrite));
+    return *this;
+}
+
+Packet& Packet::operator<<(s64 in_data) {
+    s64 toWrite = htonll(in_data);
+    Append(&toWrite, sizeof(toWrite));
+    return *this;
+}
+
+Packet& Packet::operator<<(u64 in_data) {
+    u64 toWrite = htonll(in_data);
+    Append(&toWrite, sizeof(toWrite));
+    return *this;
+}
+
+Packet& Packet::operator<<(float in_data) {
+    Append(&in_data, sizeof(in_data));
+    return *this;
+}
+
+Packet& Packet::operator<<(double in_data) {
+    Append(&in_data, sizeof(in_data));
+    return *this;
+}
+
+Packet& Packet::operator<<(const char* in_data) {
+    // First insert string length
+    u32 length = static_cast<u32>(std::strlen(in_data));
+    *this << length;
+
+    // Then insert characters
+    Append(in_data, length * sizeof(char));
+
+    return *this;
+}
+
+Packet& Packet::operator<<(const std::string& in_data) {
+    // First insert string length
+    u32 length = static_cast<u32>(in_data.size());
+    *this << length;
+
+    // Then insert characters
+    if (length > 0)
+        Append(in_data.c_str(), length * sizeof(std::string::value_type));
+
+    return *this;
+}
+
+bool Packet::CheckSize(std::size_t size) {
+    is_valid = is_valid && (read_pos + size <= data.size());
+
+    return is_valid;
+}
+
+} // namespace Network

src/network/packet.h

+// Copyright 2017 Citra Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#pragma once
+
+#include <array>
+#include <vector>
+#include "common/common_types.h"
+
+namespace Network {
+
+/// A class that serializes data for network transfer. It also handles endianess
+class Packet {
+public:
+    Packet() = default;
+    ~Packet() = default;
+
+    /**
+     * Append data to the end of the packet
+     * @param data        Pointer to the sequence of bytes to append
+     * @param size_in_bytes Number of bytes to append
+     */
+    void Append(const void* data, std::size_t size_in_bytes);
+
+    /**
+     * Reads data from the current read position of the packet
+     * @param out_data        Pointer where the data should get written to
+     * @param size_in_bytes Number of bytes to read
+     */
+    void Read(void* out_data, std::size_t size_in_bytes);
+
+    /**
+     * Clear the packet
+     * After calling Clear, the packet is empty.
+     */
+    void Clear();
+
+    /**
+     * Ignores bytes while reading
+     * @param length THe number of bytes to ignore
+     */
+    void IgnoreBytes(u32 length);
+
+    /**
+     * Get a pointer to the data contained in the packet
+     * @return Pointer to the data
+     */
+    const void* GetData() const;
+
+    /**
+     * This function returns the number of bytes pointed to by
+     * what getData returns.
+     * @return Data size, in bytes
+     */
+    std::size_t GetDataSize() const;
+
+    /**
+     * This function is useful to know if there is some data
+     * left to be read, without actually reading it.
+     * @return True if all data was read, false otherwise
+     */
+    bool EndOfPacket() const;
+
+    explicit operator bool() const;
+
+    /// Overloads of operator >> to read data from the packet
+    Packet& operator>>(bool& out_data);
+    Packet& operator>>(s8& out_data);
+    Packet& operator>>(u8& out_data);
+    Packet& operator>>(s16& out_data);
+    Packet& operator>>(u16& out_data);
+    Packet& operator>>(s32& out_data);
+    Packet& operator>>(u32& out_data);
+    Packet& operator>>(s64& out_data);
+    Packet& operator>>(u64& out_data);
+    Packet& operator>>(float& out_data);
+    Packet& operator>>(double& out_data);
+    Packet& operator>>(char* out_data);
+    Packet& operator>>(std::string& out_data);
+    template <typename T>
+    Packet& operator>>(std::vector<T>& out_data);
+    template <typename T, std::size_t S>
+    Packet& operator>>(std::array<T, S>& out_data);
+
+    /// Overloads of operator << to write data into the packet
+    Packet& operator<<(bool in_data);
+    Packet& operator<<(s8 in_data);
+    Packet& operator<<(u8 in_data);
+    Packet& operator<<(s16 in_data);
+    Packet& operator<<(u16 in_data);
+    Packet& operator<<(s32 in_data);
+    Packet& operator<<(u32 in_data);
+    Packet& operator<<(s64 in_data);
+    Packet& operator<<(u64 in_data);
+    Packet& operator<<(float in_data);
+    Packet& operator<<(double in_data);
+    Packet& operator<<(const char* in_data);
+    Packet& operator<<(const std::string& in_data);
+    template <typename T>
+    Packet& operator<<(const std::vector<T>& in_data);
+    template <typename T, std::size_t S>
+    Packet& operator<<(const std::array<T, S>& data);
+
+private:
+    /**
+     * Check if the packet can extract a given number of bytes
+     * This function updates accordingly the state of the packet.
+     * @param size Size to check
+     * @return True if size bytes can be read from the packet
+     */
+    bool CheckSize(std::size_t size);
+
+    // Member data
+    std::vector<char> data;   ///< Data stored in the packet
+    std::size_t read_pos = 0; ///< Current reading position in the packet
+    bool is_valid = true;     ///< Reading state of the packet
+};
+
+template <typename T>
+Packet& Packet::operator>>(std::vector<T>& out_data) {
+    // First extract the size
+    u32 size = 0;
+    *this >> size;
+    out_data.resize(size);
+
+    // Then extract the data
+    for (std::size_t i = 0; i < out_data.size(); ++i) {
+        T character;
+        *this >> character;
+        out_data[i] = character;
+    }
+    return *this;
+}
+
+template <typename T, std::size_t S>
+Packet& Packet::operator>>(std::array<T, S>& out_data) {
+    for (std::size_t i = 0; i < out_data.size(); ++i) {
+        T character;
+        *this >> character;
+        out_data[i] = character;
+    }
+    return *this;
+}
+
+template <typename T>
+Packet& Packet::operator<<(const std::vector<T>& in_data) {
+    // First insert the size
+    *this << static_cast<u32>(in_data.size());
+
+    // Then insert the data
+    for (std::size_t i = 0; i < in_data.size(); ++i) {
+        *this << in_data[i];
+    }
+    return *this;
+}
+
+template <typename T, std::size_t S>
+Packet& Packet::operator<<(const std::array<T, S>& in_data) {
+    for (std::size_t i = 0; i < in_data.size(); ++i) {
+        *this << in_data[i];
+    }
+    return *this;
+}
+
+} // namespace Network

src/network/room.h

+// Copyright 2017 Citra Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#pragma once
+
+#include <array>
+#include <memory>
+#include <string>
+#include <vector>
+#include "common/common_types.h"
+#include "network/verify_user.h"
+
+namespace Network {
+
+constexpr u32 network_version = 4; ///< The version of this Room and RoomMember
+
+constexpr u16 DefaultRoomPort = 24872;
+
+constexpr u32 MaxMessageSize = 500;
+
+/// Maximum number of concurrent connections allowed to this room.
+static constexpr u32 MaxConcurrentConnections = 254;
+
+constexpr std::size_t NumChannels = 1; // Number of channels used for the connection
+
+struct RoomInformation {
+    std::string name;           ///< Name of the server
+    std::string description;    ///< Server description
+    u32 member_slots;           ///< Maximum number of members in this room
+    u16 port;                   ///< The port of this room
+    std::string preferred_game; ///< Game to advertise that you want to play
+    u64 preferred_game_id;      ///< Title ID for the advertised game
+    std::string host_username;  ///< Forum username of the host
+    bool enable_citra_mods;     ///< Allow Citra Moderators to moderate on this room
+};
+
+struct GameInfo {
+    std::string name{""};
+    u64 id{0};
+};
+
+using MacAddress = std::array<u8, 6>;
+/// A special MAC address that tells the room we're joining to assign us a MAC address
+/// automatically.
+constexpr MacAddress NoPreferredMac = {0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF};
+
+// 802.11 broadcast MAC address
+constexpr MacAddress BroadcastMac = {0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF};
+
+// The different types of messages that can be sent. The first byte of each packet defines the type
+enum RoomMessageTypes : u8 {
+    IdJoinRequest = 1,
+    IdJoinSuccess,
+    IdRoomInformation,
+    IdSetGameInfo,
+    IdWifiPacket,
+    IdChatMessage,
+    IdNameCollision,
+    IdMacCollision,
+    IdVersionMismatch,
+    IdWrongPassword,
+    IdCloseRoom,
+    IdRoomIsFull,
+    IdConsoleIdCollision,
+    IdStatusMessage,
+    IdHostKicked,
+    IdHostBanned,
+    /// Moderation requests
+    IdModKick,
+    IdModBan,
+    IdModUnban,
+    IdModGetBanList,
+    // Moderation responses
+    IdModBanListResponse,
+    IdModPermissionDenied,
+    IdModNoSuchUser,
+    IdJoinSuccessAsMod,
+};
+
+/// Types of system status messages
+enum StatusMessageTypes : u8 {
+    IdMemberJoin = 1,  ///< Member joining
+    IdMemberLeave,     ///< Member leaving
+    IdMemberKicked,    ///< A member is kicked from the room
+    IdMemberBanned,    ///< A member is banned from the room
+    IdAddressUnbanned, ///< A username / ip address is unbanned from the room
+};
+
+/// This is what a server [person creating a server] would use.
+class Room final {
+public:
+    enum class State : u8 {
+        Open,   ///< The room is open and ready to accept connections.
+        Closed, ///< The room is not opened and can not accept connections.
+    };
+
+    struct Member {
+        std::string nickname;     ///< The nickname of the member.
+        std::string username;     ///< The web services username of the member. Can be empty.
+        std::string display_name; ///< The web services display name of the member. Can be empty.
+        std::string avatar_url;   ///< Url to the member's avatar. Can be empty.
+        GameInfo game_info;       ///< The current game of the member
+        MacAddress mac_address;   ///< The assigned mac address of the member.
+    };
+
+    Room();
+    ~Room();
+
+    /**
+     * Gets the current state of the room.
+     */
+    State GetState() const;
+
+    /**
+     * Gets the room information of the room.
+     */
+    const RoomInformation& GetRoomInformation() const;
+
+    /**
+     * Gets the verify UID of this room.
+     */
+    std::string GetVerifyUID() const;
+
+    /**
+     * Gets a list of the mbmers connected to the room.
+     */
+    std::vector<Member> GetRoomMemberList() const;
+
+    /**
+     * Checks if the room is password protected
+     */
+    bool HasPassword() const;
+
+    using UsernameBanList = std::vector<std::string>;
+    using IPBanList = std::vector<std::string>;
+
+    using BanList = std::pair<UsernameBanList, IPBanList>;
+
+    /**
+     * Creates the socket for this room. Will bind to default address if
+     * server is empty string.
+     */
+    bool Create(const std::string& name, const std::string& description = "",
+                const std::string& server = "", u16 server_port = DefaultRoomPort,
+                const std::string& password = "",
+                const u32 max_connections = MaxConcurrentConnections,
+                const std::string& host_username = "", const std::string& preferred_game = "",
+                u64 preferred_game_id = 0,
+                std::unique_ptr<VerifyUser::Backend> verify_backend = nullptr,
+                const BanList& ban_list = {}, bool enable_citra_mods = false);
+
+    /**
+     * Sets the verification GUID of the room.
+     */
+    void SetVerifyUID(const std::string& uid);
+
+    /**
+     * Gets the ban list (including banned forum usernames and IPs) of the room.
+     */
+    BanList GetBanList() const;
+
+    /**
+     * Destroys the socket
+     */
+    void Destroy();
+
+private:
+    class RoomImpl;
+    std::unique_ptr<RoomImpl> room_impl;
+};
+
+} // namespace Network

src/network/room_member.h

+// Copyright 2017 Citra Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#pragma once
+
+#include <functional>
+#include <memory>
+#include <string>
+#include <vector>
+#include <boost/serialization/vector.hpp>
+#include "common/common_types.h"
+#include "network/room.h"
+
+namespace Network {
+
+/// Information about the received WiFi packets.
+/// Acts as our own 802.11 header.
+struct WifiPacket {
+    enum class PacketType : u8 {
+        Beacon,
+        Data,
+        Authentication,
+        AssociationResponse,
+        Deauthentication,
+        NodeMap
+    };
+    PacketType type;      ///< The type of 802.11 frame.
+    std::vector<u8> data; ///< Raw 802.11 frame data, starting at the management frame header
+                          /// for management frames.
+    MacAddress transmitter_address; ///< Mac address of the transmitter.
+    MacAddress destination_address; ///< Mac address of the receiver.
+    u8 channel;                     ///< WiFi channel where this frame was transmitted.
+
+private:
+    template <class Archive>
+    void serialize(Archive& ar, const unsigned int) {
+        ar& type;
+        ar& data;
+        ar& transmitter_address;
+        ar& destination_address;
+        ar& channel;
+    }
+    friend class boost::serialization::access;
+};
+
+/// Represents a chat message.
+struct ChatEntry {
+    std::string nickname; ///< Nickname of the client who sent this message.
+    /// Web services username of the client who sent this message, can be empty.
+    std::string username;
+    std::string message; ///< Body of the message.
+};
+
+/// Represents a system status message.
+struct StatusMessageEntry {
+    StatusMessageTypes type; ///< Type of the message
+    /// Subject of the message. i.e. the user who is joining/leaving/being banned, etc.
+    std::string nickname;
+    std::string username;
+};
+
+/**
+ * This is what a client [person joining a server] would use.
+ * It also has to be used if you host a game yourself (You'd create both, a Room and a
+ * RoomMembership for yourself)
+ */
+class RoomMember final {
+public:
+    enum class State : u8 {
+        Uninitialized, ///< Not initialized
+        Idle,          ///< Default state (i.e. not connected)
+        Joining,       ///< The client is attempting to join a room.
+        Joined,    ///< The client is connected to the room and is ready to send/receive packets.
+        Moderator, ///< The client is connnected to the room and is granted mod permissions.
+    };
+
+    enum class Error : u8 {
+        // Reasons why connection was closed
+        LostConnection, ///< Connection closed
+        HostKicked,     ///< Kicked by the host
+
+        // Reasons why connection was rejected
+        UnknownError,       ///< Some error [permissions to network device missing or something]
+        NameCollision,      ///< Somebody is already using this name
+        MacCollision,       ///< Somebody is already using that mac-address
+        ConsoleIdCollision, ///< Somebody in the room has the same Console ID
+        WrongVersion,       ///< The room version is not the same as for this RoomMember
+        WrongPassword,      ///< The password doesn't match the one from the Room
+        CouldNotConnect,    ///< The room is not responding to a connection attempt
+        RoomIsFull,         ///< Room is already at the maximum number of players
+        HostBanned,         ///< The user is banned by the host
+
+        // Reasons why moderation request failed
+        PermissionDenied, ///< The user does not have mod permissions
+        NoSuchUser,       ///< The nickname the user attempts to kick/ban does not exist
+    };
+
+    struct MemberInformation {
+        std::string nickname;     ///< Nickname of the member.
+        std::string username;     ///< The web services username of the member. Can be empty.
+        std::string display_name; ///< The web services display name of the member. Can be empty.
+        std::string avatar_url;   ///< Url to the member's avatar. Can be empty.
+        GameInfo game_info;     ///< Name of the game they're currently playing, or empty if they're
+                                /// not playing anything.
+        MacAddress mac_address; ///< MAC address associated with this member.
+    };
+    using MemberList = std::vector<MemberInformation>;
+
+    // The handle for the callback functions
+    template <typename T>
+    using CallbackHandle = std::shared_ptr<std::function<void(const T&)>>;
+
+    /**
+     * Unbinds a callback function from the events.
+     * @param handle The connection handle to disconnect
+     */
+    template <typename T>
+    void Unbind(CallbackHandle<T> handle);
+
+    RoomMember();
+    ~RoomMember();
+
+    /**
+     * Returns the status of our connection to the room.
+     */
+    State GetState() const;
+
+    /**
+     * Returns information about the members in the room we're currently connected to.
+     */
+    const MemberList& GetMemberInformation() const;
+
+    /**
+     * Returns the nickname of the RoomMember.
+     */
+    const std::string& GetNickname() const;
+
+    /**
+     * Returns the username of the RoomMember.
+     */
+    const std::string& GetUsername() const;
+
+    /**
+     * Returns the MAC address of the RoomMember.
+     */
+    const MacAddress& GetMacAddress() const;
+
+    /**
+     * Returns information about the room we're currently connected to.
+     */
+    RoomInformation GetRoomInformation() const;
+
+    /**
+     * Returns whether we're connected to a server or not.
+     */
+    bool IsConnected() const;
+
+    /**
+     * Attempts to join a room at the specified address and port, using the specified nickname.
+     * A console ID hash is passed in to check console ID conflicts.
+     * This may fail if the username or console ID is already taken.
+     */
+    void Join(const std::string& nickname, const std::string& console_id_hash,
+              const char* server_addr = "127.0.0.1", u16 server_port = DefaultRoomPort,
+              u16 client_port = 0, const MacAddress& preferred_mac = NoPreferredMac,
+              const std::string& password = "", const std::string& token = "");
+
+    /**
+     * Sends a WiFi packet to the room.
+     * @param packet The WiFi packet to send.
+     */
+    void SendWifiPacket(const WifiPacket& packet);
+
+    /**
+     * Sends a chat message to the room.
+     * @param message The contents of the message.
+     */
+    void SendChatMessage(const std::string& message);
+
+    /**
+     * Sends the current game info to the room.
+     * @param game_info The game information.
+     */
+    void SendGameInfo(const GameInfo& game_info);
+
+    /**
+     * Sends a moderation request to the room.
+     * @param type Moderation request type.
+     * @param nickname The subject of the request. (i.e. the user you want to kick/ban)
+     */
+    void SendModerationRequest(RoomMessageTypes type, const std::string& nickname);
+
+    /**
+     * Attempts to retrieve ban list from the room.
+     * If success, the ban list callback would be called. Otherwise an error would be emitted.
+     */
+    void RequestBanList();
+
+    /**
+     * Binds a function to an event that will be triggered every time the State of the member
+     * changed. The function wil be called every time the event is triggered. The callback function
+     * must not bind or unbind a function. Doing so will cause a deadlock
+     * @param callback The function to call
+     * @return A handle used for removing the function from the registered list
+     */
+    CallbackHandle<State> BindOnStateChanged(std::function<void(const State&)> callback);
+
+    /**
+     * Binds a function to an event that will be triggered every time an error happened. The
+     * function wil be called every time the event is triggered. The callback function must not bind
+     * or unbind a function. Doing so will cause a deadlock
+     * @param callback The function to call
+     * @return A handle used for removing the function from the registered list
+     */
+    CallbackHandle<Error> BindOnError(std::function<void(const Error&)> callback);
+
+    /**
+     * Binds a function to an event that will be triggered every time a WifiPacket is received.
+     * The function wil be called everytime the event is triggered.
+     * The callback function must not bind or unbind a function. Doing so will cause a deadlock
+     * @param callback The function to call
+     * @return A handle used for removing the function from the registered list
+     */
+    CallbackHandle<WifiPacket> BindOnWifiPacketReceived(
+        std::function<void(const WifiPacket&)> callback);
+
+    /**
+     * Binds a function to an event that will be triggered every time the RoomInformation changes.
+     * The function wil be called every time the event is triggered.
+     * The callback function must not bind or unbind a function. Doing so will cause a deadlock
+     * @param callback The function to call
+     * @return A handle used for removing the function from the registered list
+     */
+    CallbackHandle<RoomInformation> BindOnRoomInformationChanged(
+        std::function<void(const RoomInformation&)> callback);
+
+    /**
+     * Binds a function to an event that will be triggered every time a ChatMessage is received.
+     * The function wil be called every time the event is triggered.
+     * The callback function must not bind or unbind a function. Doing so will cause a deadlock
+     * @param callback The function to call
+     * @return A handle used for removing the function from the registered list
+     */
+    CallbackHandle<ChatEntry> BindOnChatMessageRecieved(
+        std::function<void(const ChatEntry&)> callback);
+
+    /**
+     * Binds a function to an event that will be triggered every time a StatusMessage is
+     * received. The function will be called every time the event is triggered. The callback
+     * function must not bind or unbind a function. Doing so will cause a deadlock
+     * @param callback The function to call
+     * @return A handle used for removing the function from the registered list
+     */
+    CallbackHandle<StatusMessageEntry> BindOnStatusMessageReceived(
+        std::function<void(const StatusMessageEntry&)> callback);
+
+    /**
+     * Binds a function to an event that will be triggered every time a requested ban list
+     * received. The function will be called every time the event is triggered. The callback
+     * function must not bind or unbind a function. Doing so will cause a deadlock
+     * @param callback The function to call
+     * @return A handle used for removing the function from the registered list
+     */
+    CallbackHandle<Room::BanList> BindOnBanListReceived(
+        std::function<void(const Room::BanList&)> callback);
+
+    /**
+     * Leaves the current room.
+     */
+    void Leave();
+
+private:
+    class RoomMemberImpl;
+    std::unique_ptr<RoomMemberImpl> room_member_impl;
+};
+
+inline const char* GetStateStr(const RoomMember::State& s) {
+    switch (s) {
+    case RoomMember::State::Uninitialized:
+        return "Uninitialized";
+    case RoomMember::State::Idle:
+        return "Idle";
+    case RoomMember::State::Joining:
+        return "Joining";
+    case RoomMember::State::Joined:
+        return "Joined";
+    case RoomMember::State::Moderator:
+        return "Moderator";
+    }
+    return "Unknown";
+}
+
+inline const char* GetErrorStr(const RoomMember::Error& e) {
+    switch (e) {
+    case RoomMember::Error::LostConnection:
+        return "LostConnection";
+    case RoomMember::Error::HostKicked:
+        return "HostKicked";
+    case RoomMember::Error::UnknownError:
+        return "UnknownError";
+    case RoomMember::Error::NameCollision:
+        return "NameCollision";
+    case RoomMember::Error::MacCollision:
+        return "MaxCollision";
+    case RoomMember::Error::ConsoleIdCollision:
+        return "ConsoleIdCollision";
+    case RoomMember::Error::WrongVersion:
+        return "WrongVersion";
+    case RoomMember::Error::WrongPassword:
+        return "WrongPassword";
+    case RoomMember::Error::CouldNotConnect:
+        return "CouldNotConnect";
+    case RoomMember::Error::RoomIsFull:
+        return "RoomIsFull";
+    case RoomMember::Error::HostBanned:
+        return "HostBanned";
+    case RoomMember::Error::PermissionDenied:
+        return "PermissionDenied";
+    case RoomMember::Error::NoSuchUser:
+        return "NoSuchUser";
+    default:
+        return "Unknown";
+    }
+}
+
+} // namespace Network

src/network/verify_user.cpp

+// Copyright 2018 Citra Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#include "network/verify_user.h"
+
+namespace Network::VerifyUser {
+
+Backend::~Backend() = default;
+
+NullBackend::~NullBackend() = default;
+
+UserData NullBackend::LoadUserData([[maybe_unused]] const std::string& verify_UID,
+                                   [[maybe_unused]] const std::string& token) {
+    return {};
+}
+
+} // namespace Network::VerifyUser

src/network/verify_user.h

+// Copyright 2018 Citra Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#pragma once
+
+#include <string>
+#include "common/logging/log.h"
+
+namespace Network::VerifyUser {
+
+struct UserData {
+    std::string username;
+    std::string display_name;
+    std::string avatar_url;
+    bool moderator = false; ///< Whether the user is a Citra Moderator.
+};
+
+/**
+ * A backend used for verifying users and loading user data.
+ */
+class Backend {
+public:
+    virtual ~Backend();
+
+    /**
+     * Verifies the given token and loads the information into a UserData struct.
+     * @param verify_UID A GUID that may be used for verification.
+     * @param token A token that contains user data and verification data. The format and content is
+     * decided by backends.
+     */
+    virtual UserData LoadUserData(const std::string& verify_UID, const std::string& token) = 0;
+};
+
+/**
+ * A null backend where the token is ignored.
+ * No verification is performed here and the function returns an empty UserData.
+ */
+class NullBackend final : public Backend {
+public:
+    ~NullBackend();
+
+    UserData LoadUserData(const std::string& verify_UID, const std::string& token) override;
+};
+
+} // namespace Network::VerifyUser