//====== Copyright © 1996-2008, Valve Corporation, All rights reserved. ======= // // Purpose: interface to steam managing network connections between game clients & servers // //============================================================================= #ifndef ISTEAMNETWORKING #define ISTEAMNETWORKING #ifdef STEAM_WIN32 #pragma once #endif #include "steam_api_common.h" // list of possible errors returned by SendP2PPacket() API // these will be posted in the P2PSessionConnectFail_t callback enum EP2PSessionError { k_EP2PSessionErrorNone = 0, k_EP2PSessionErrorNotRunningApp = 1, // target is not running the same game k_EP2PSessionErrorNoRightsToApp = 2, // local user doesn't own the app that is running k_EP2PSessionErrorDestinationNotLoggedIn = 3, // target user isn't connected to Steam k_EP2PSessionErrorTimeout = 4, // target isn't responding, perhaps not calling AcceptP2PSessionWithUser() // corporate firewalls can also block this (NAT traversal is not firewall traversal) // make sure that UDP ports 3478, 4379, and 4380 are open in an outbound direction k_EP2PSessionErrorMax = 5 }; // SendP2PPacket() send types // Typically k_EP2PSendUnreliable is what you want for UDP-like packets, k_EP2PSendReliable for TCP-like packets enum EP2PSend { // Basic UDP send. Packets can't be bigger than 1200 bytes (your typical MTU size). Can be lost, or arrive out of order (rare). // The sending API does have some knowledge of the underlying connection, so if there is no NAT-traversal accomplished or // there is a recognized adjustment happening on the connection, the packet will be batched until the connection is open again. k_EP2PSendUnreliable = 0, // As above, but if the underlying p2p connection isn't yet established the packet will just be thrown away. Using this on the first // packet sent to a remote host almost guarantees the packet will be dropped. // This is only really useful for kinds of data that should never buffer up, i.e. voice payload packets k_EP2PSendUnreliableNoDelay = 1, // Reliable message send. Can send up to 1MB of data in a single message. // Does fragmentation/re-assembly of messages under the hood, as well as a sliding window for efficient sends of large chunks of data. k_EP2PSendReliable = 2, // As above, but applies the Nagle algorithm to the send - sends will accumulate // until the current MTU size (typically ~1200 bytes, but can change) or ~200ms has passed (Nagle algorithm). // Useful if you want to send a set of smaller messages but have the coalesced into a single packet // Since the reliable stream is all ordered, you can do several small message sends with k_EP2PSendReliableWithBuffering and then // do a normal k_EP2PSendReliable to force all the buffered data to be sent. k_EP2PSendReliableWithBuffering = 3, }; // connection state to a specified user, returned by GetP2PSessionState() // this is under-the-hood info about what's going on with a SendP2PPacket(), shouldn't be needed except for debuggin #if defined( VALVE_CALLBACK_PACK_SMALL ) #pragma pack( push, 4 ) #elif defined( VALVE_CALLBACK_PACK_LARGE ) #pragma pack( push, 8 ) #else #error steam_api_common.h should define VALVE_CALLBACK_PACK_xxx #endif struct P2PSessionState_t { uint8 m_bConnectionActive; // true if we've got an active open connection uint8 m_bConnecting; // true if we're currently trying to establish a connection uint8 m_eP2PSessionError; // last error recorded (see enum above) uint8 m_bUsingRelay; // true if it's going through a relay server (TURN) int32 m_nBytesQueuedForSend; int32 m_nPacketsQueuedForSend; uint32 m_nRemoteIP; // potential IP:Port of remote host. Could be TURN server. uint16 m_nRemotePort; // Only exists for compatibility with older authentication api's }; #pragma pack( pop ) // handle to a socket typedef uint32 SNetSocket_t; // CreateP2PConnectionSocket() typedef uint32 SNetListenSocket_t; // CreateListenSocket() // connection progress indicators, used by CreateP2PConnectionSocket() enum ESNetSocketState { k_ESNetSocketStateInvalid = 0, // communication is valid k_ESNetSocketStateConnected = 1, // states while establishing a connection k_ESNetSocketStateInitiated = 10, // the connection state machine has started // p2p connections k_ESNetSocketStateLocalCandidatesFound = 11, // we've found our local IP info k_ESNetSocketStateReceivedRemoteCandidates = 12,// we've received information from the remote machine, via the Steam back-end, about their IP info // direct connections k_ESNetSocketStateChallengeHandshake = 15, // we've received a challenge packet from the server // failure states k_ESNetSocketStateDisconnecting = 21, // the API shut it down, and we're in the process of telling the other end k_ESNetSocketStateLocalDisconnect = 22, // the API shut it down, and we've completed shutdown k_ESNetSocketStateTimeoutDuringConnect = 23, // we timed out while trying to creating the connection k_ESNetSocketStateRemoteEndDisconnected = 24, // the remote end has disconnected from us k_ESNetSocketStateConnectionBroken = 25, // connection has been broken; either the other end has disappeared or our local network connection has broke }; // describes how the socket is currently connected enum ESNetSocketConnectionType { k_ESNetSocketConnectionTypeNotConnected = 0, k_ESNetSocketConnectionTypeUDP = 1, k_ESNetSocketConnectionTypeUDPRelay = 2, }; //----------------------------------------------------------------------------- // Purpose: Functions for making connections and sending data between clients, // traversing NAT's where possible // // NOTE: This interface is deprecated and may be removed in a future release of /// the Steamworks SDK. Please see ISteamNetworkingSockets and /// ISteamNetworkingMessages //----------------------------------------------------------------------------- class ISteamNetworking { public: //////////////////////////////////////////////////////////////////////////////////////////// // // UDP-style (connectionless) networking interface. These functions send messages using // an API organized around the destination. Reliable and unreliable messages are supported. // // For a more TCP-style interface (meaning you have a connection handle), see the functions below. // Both interface styles can send both reliable and unreliable messages. // // Automatically establishes NAT-traversing or Relay server connections // // These APIs are deprecated, and may be removed in a future version of the Steamworks // SDK. See ISteamNetworkingMessages. // Sends a P2P packet to the specified user // UDP-like, unreliable and a max packet size of 1200 bytes // the first packet send may be delayed as the NAT-traversal code runs // if we can't get through to the user, an error will be posted via the callback P2PSessionConnectFail_t // see EP2PSend enum above for the descriptions of the different ways of sending packets // // nChannel is a routing number you can use to help route message to different systems - you'll have to call ReadP2PPacket() // with the same channel number in order to retrieve the data on the other end // using different channels to talk to the same user will still use the same underlying p2p connection, saving on resources virtual bool SendP2PPacket( CSteamID steamIDRemote, const void *pubData, uint32 cubData, EP2PSend eP2PSendType, int nChannel = 0 ) = 0; // returns true if any data is available for read, and the amount of data that will need to be read virtual bool IsP2PPacketAvailable( uint32 *pcubMsgSize, int nChannel = 0 ) = 0; // reads in a packet that has been sent from another user via SendP2PPacket() // returns the size of the message and the steamID of the user who sent it in the last two parameters // if the buffer passed in is too small, the message will be truncated // this call is not blocking, and will return false if no data is available virtual bool ReadP2PPacket( void *pubDest, uint32 cubDest, uint32 *pcubMsgSize, CSteamID *psteamIDRemote, int nChannel = 0 ) = 0; // AcceptP2PSessionWithUser() should only be called in response to a P2PSessionRequest_t callback // P2PSessionRequest_t will be posted if another user tries to send you a packet that you haven't talked to yet // if you don't want to talk to the user, just ignore the request // if the user continues to send you packets, another P2PSessionRequest_t will be posted periodically // this may be called multiple times for a single user // (if you've called SendP2PPacket() on the other user, this implicitly accepts the session request) virtual bool AcceptP2PSessionWithUser( CSteamID steamIDRemote ) = 0; // call CloseP2PSessionWithUser() when you're done talking to a user, will free up resources under-the-hood // if the remote user tries to send data to you again, another P2PSessionRequest_t callback will be posted virtual bool CloseP2PSessionWithUser( CSteamID steamIDRemote ) = 0; // call CloseP2PChannelWithUser() when you're done talking to a user on a specific channel. Once all channels // open channels to a user have been closed, the open session to the user will be closed and new data from this // user will trigger a P2PSessionRequest_t callback virtual bool CloseP2PChannelWithUser( CSteamID steamIDRemote, int nChannel ) = 0; // fills out P2PSessionState_t structure with details about the underlying connection to the user // should only needed for debugging purposes // returns false if no connection exists to the specified user virtual bool GetP2PSessionState( CSteamID steamIDRemote, P2PSessionState_t *pConnectionState ) = 0; // Allow P2P connections to fall back to being relayed through the Steam servers if a direct connection // or NAT-traversal cannot be established. Only applies to connections created after setting this value, // or to existing connections that need to automatically reconnect after this value is set. // // P2P packet relay is allowed by default // // NOTE: This function is deprecated and may be removed in a future version of the SDK. For // security purposes, we may decide to relay the traffic to certain peers, even if you pass false // to this function, to prevent revealing the client's IP address top another peer. virtual bool AllowP2PPacketRelay( bool bAllow ) = 0; //////////////////////////////////////////////////////////////////////////////////////////// // // LISTEN / CONNECT connection-oriented interface functions // // These functions are more like a client-server TCP API. One side is the "server" // and "listens" for incoming connections, which then must be "accepted." The "client" // initiates a connection by "connecting." Sending and receiving is done through a // connection handle. // // For a more UDP-style interface, where you do not track connection handles but // simply send messages to a SteamID, use the UDP-style functions above. // // Both methods can send both reliable and unreliable methods. // // These APIs are deprecated, and may be removed in a future version of the Steamworks // SDK. See ISteamNetworkingSockets. // //////////////////////////////////////////////////////////////////////////////////////////// // creates a socket and listens others to connect // will trigger a SocketStatusCallback_t callback on another client connecting // nVirtualP2PPort is the unique ID that the client will connect to, in case you have multiple ports // this can usually just be 0 unless you want multiple sets of connections // unIP is the local IP address to bind to // pass in 0 if you just want the default local IP // unPort is the port to use // pass in 0 if you don't want users to be able to connect via IP/Port, but expect to be always peer-to-peer connections only virtual SNetListenSocket_t CreateListenSocket( int nVirtualP2PPort, SteamIPAddress_t nIP, uint16 nPort, bool bAllowUseOfPacketRelay ) = 0; // creates a socket and begin connection to a remote destination // can connect via a known steamID (client or game server), or directly to an IP // on success will trigger a SocketStatusCallback_t callback // on failure or timeout will trigger a SocketStatusCallback_t callback with a failure code in m_eSNetSocketState virtual SNetSocket_t CreateP2PConnectionSocket( CSteamID steamIDTarget, int nVirtualPort, int nTimeoutSec, bool bAllowUseOfPacketRelay ) = 0; virtual SNetSocket_t CreateConnectionSocket( SteamIPAddress_t nIP, uint16 nPort, int nTimeoutSec ) = 0; // disconnects the connection to the socket, if any, and invalidates the handle // any unread data on the socket will be thrown away // if bNotifyRemoteEnd is set, socket will not be completely destroyed until the remote end acknowledges the disconnect virtual bool DestroySocket( SNetSocket_t hSocket, bool bNotifyRemoteEnd ) = 0; // destroying a listen socket will automatically kill all the regular sockets generated from it virtual bool DestroyListenSocket( SNetListenSocket_t hSocket, bool bNotifyRemoteEnd ) = 0; // sending data // must be a handle to a connected socket // data is all sent via UDP, and thus send sizes are limited to 1200 bytes; after this, many routers will start dropping packets // use the reliable flag with caution; although the resend rate is pretty aggressive, // it can still cause stalls in receiving data (like TCP) virtual bool SendDataOnSocket( SNetSocket_t hSocket, void *pubData, uint32 cubData, bool bReliable ) = 0; // receiving data // returns false if there is no data remaining // fills out *pcubMsgSize with the size of the next message, in bytes virtual bool IsDataAvailableOnSocket( SNetSocket_t hSocket, uint32 *pcubMsgSize ) = 0; // fills in pubDest with the contents of the message // messages are always complete, of the same size as was sent (i.e. packetized, not streaming) // if *pcubMsgSize < cubDest, only partial data is written // returns false if no data is available virtual bool RetrieveDataFromSocket( SNetSocket_t hSocket, void *pubDest, uint32 cubDest, uint32 *pcubMsgSize ) = 0; // checks for data from any socket that has been connected off this listen socket // returns false if there is no data remaining // fills out *pcubMsgSize with the size of the next message, in bytes // fills out *phSocket with the socket that data is available on virtual bool IsDataAvailable( SNetListenSocket_t hListenSocket, uint32 *pcubMsgSize, SNetSocket_t *phSocket ) = 0; // retrieves data from any socket that has been connected off this listen socket // fills in pubDest with the contents of the message // messages are always complete, of the same size as was sent (i.e. packetized, not streaming) // if *pcubMsgSize < cubDest, only partial data is written // returns false if no data is available // fills out *phSocket with the socket that data is available on virtual bool RetrieveData( SNetListenSocket_t hListenSocket, void *pubDest, uint32 cubDest, uint32 *pcubMsgSize, SNetSocket_t *phSocket ) = 0; // returns information about the specified socket, filling out the contents of the pointers virtual bool GetSocketInfo( SNetSocket_t hSocket, CSteamID *pSteamIDRemote, int *peSocketStatus, SteamIPAddress_t *punIPRemote, uint16 *punPortRemote ) = 0; // returns which local port the listen socket is bound to // *pnIP and *pnPort will be 0 if the socket is set to listen for P2P connections only virtual bool GetListenSocketInfo( SNetListenSocket_t hListenSocket, SteamIPAddress_t *pnIP, uint16 *pnPort ) = 0; // returns true to describe how the socket ended up connecting virtual ESNetSocketConnectionType GetSocketConnectionType( SNetSocket_t hSocket ) = 0; // max packet size, in bytes virtual int GetMaxPacketSize( SNetSocket_t hSocket ) = 0; }; #define STEAMNETWORKING_INTERFACE_VERSION "SteamNetworking006" #ifndef STEAM_API_EXPORTS // Global interface accessor inline ISteamNetworking *SteamNetworking(); STEAM_DEFINE_USER_INTERFACE_ACCESSOR( ISteamNetworking *, SteamNetworking, STEAMNETWORKING_INTERFACE_VERSION ); // Global accessor for the gameserver client inline ISteamNetworking *SteamGameServerNetworking(); STEAM_DEFINE_GAMESERVER_INTERFACE_ACCESSOR( ISteamNetworking *, SteamGameServerNetworking, STEAMNETWORKING_INTERFACE_VERSION ); #endif // callbacks #if defined( VALVE_CALLBACK_PACK_SMALL ) #pragma pack( push, 4 ) #elif defined( VALVE_CALLBACK_PACK_LARGE ) #pragma pack( push, 8 ) #else #error steam_api_common.h should define VALVE_CALLBACK_PACK_xxx #endif // callback notification - a user wants to talk to us over the P2P channel via the SendP2PPacket() API // in response, a call to AcceptP2PPacketsFromUser() needs to be made, if you want to talk with them struct P2PSessionRequest_t { enum { k_iCallback = k_iSteamNetworkingCallbacks + 2 }; CSteamID m_steamIDRemote; // user who wants to talk to us }; // callback notification - packets can't get through to the specified user via the SendP2PPacket() API // all packets queued packets unsent at this point will be dropped // further attempts to send will retry making the connection (but will be dropped if we fail again) struct P2PSessionConnectFail_t { enum { k_iCallback = k_iSteamNetworkingCallbacks + 3 }; CSteamID m_steamIDRemote; // user we were sending packets to uint8 m_eP2PSessionError; // EP2PSessionError indicating why we're having trouble }; // callback notification - status of a socket has changed // used as part of the CreateListenSocket() / CreateP2PConnectionSocket() struct SocketStatusCallback_t { enum { k_iCallback = k_iSteamNetworkingCallbacks + 1 }; SNetSocket_t m_hSocket; // the socket used to send/receive data to the remote host SNetListenSocket_t m_hListenSocket; // this is the server socket that we were listening on; NULL if this was an outgoing connection CSteamID m_steamIDRemote; // remote steamID we have connected to, if it has one int m_eSNetSocketState; // socket state, ESNetSocketState }; #pragma pack( pop ) #endif // ISTEAMNETWORKING