InSim Relay source

For more information go to http://www.lfsforum.net/showthread.php?t=30740

// InSimRelay for LFS InSim version 4 (LFS 0.5X and up)
//
// The Relay code below can be seen as an extension to the regular 
// InSim protocol, as the packets are constructed in the same
// manner as regular InSim packets.
//
// Connect your client to isrelay.lfs.net:47474 with TCP
// After you are connected you can request a hostlist, so you can see
// which hosts you can connect to.
// Then you can send a packet to the Relay to select a host. After that
// the Relay will send you all insim data from that host.

// Some hosts require a spectator password in order to be selectable.

// You do not need to specify a spectator password if you use a valid administrator password.

// If you connect with an administrator password, you can send just about every
// regular InSim packet there is available in LFS, just like as if you were connected
// to the host directly. For a full list, see end of document.

// Packet types used for the Relay

1. define IRP_ARQ 250 // Send : request if we are host admin (after connecting to a host)
2. define IRP_ARP 251 // Receive : replies if you are admin (after connecting to a host)
3. define IRP_HLR 252 // Send : To request a hostlist
4. define IRP_HOS 253 // Receive : Hostlist info
5. define IRP_SEL 254 // Send : To select a host
6. define IRP_ERR 255 // Receive : An error number

// To request a hostlist from the Relay, send this packet :

struct IR_HLR // HostList Request { byte Size; // 4 byte Type; // IRP_HLR byte ReqI; byte Sp0; };

// That will return (multiple) packets containing hostnames and some information about them

// The following struct is a subpacket of the IR_HOS packet

struct HInfo // Sub packet for IR_HOS. Contains host information { char HName[32]; // Name of the host

char Track[6]; // Short track name byte Flags; // Info flags about the host - see NOTE 1) below byte NumConns; // Number of people on the host };

// NOTE 1)

1. define HOS_SPECPASS 1 // Host requires a spectator password
2. define HOS_LICENSED 2 // Bit is set if host is licensed
3. define HOS_S1 4 // Bit is set if host is S1
4. define HOS_S2 8 // Bit is set if host is S2
5. define HOS_FIRST 64 // Indicates the first host in the list
6. define HOS_LAST 128 // Indicates the last host in the list

struct IR_HOS // Hostlist (hosts connected to the Relay) { byte Size; // 4 + NumHosts * 40 byte Type; // IRP_HOS byte ReqI; // As given in IR_HLR byte NumHosts; // Number of hosts described in this packet

HInfo Info[6]; // Host info for every host in the Relay. 1 to 6 of these in a IR_HOS };

// To select a host in the Relay, send this packet :

struct IR_SEL // Relay select - packet to select a host, so relay starts sending you data. { byte Size; // 68 byte Type; // IRP_SEL byte ReqI; // If non-zero Relay will reply with an IS_VER packet byte Zero; // 0

char HName[32]; // Hostname to receive data from - may be colourcode stripped char Admin[16]; // Admin password (to gain admin access to host) char Spec[16]; // Spectator password (if host requires it)

};

// To request if we are an admin send:

struct IR_ARQ // Admin Request {

   byte    Size;		// 4
   byte    Type;		// IRP_ARQ
   byte    ReqI;
   byte    Sp0;

};

// Relay will reply to admin status request :

struct IR_ARP // Admin Response

{

byte Size; // 4 byte Type; // IRP_ARP byte ReqI; byte Admin; // 0- no admin; 1- admin

};

// If you specify a wrong value, like invalid packet / hostname / adminpass / specpass, // the Relay returns an error packet :

struct IR_ERR { byte Size; // 4 byte Type; // IRP_ERR byte ReqI; // As given in RL_SEL, otherwise 0 byte ErrNo; // Error number - see NOTE 2) below };

// NOTE 2) Error numbers :

1. define IR_ERR_PACKET 1 // Invalid packet sent by client (wrong structure / length)
2. define IR_ERR_PACKET2 2 // Invalid packet sent by client (packet was not allowed to be forwarded to host)
3. define IR_ERR_HOSTNAME 3 // Wrong hostname given by client
4. define IR_ERR_ADMIN 4 // Wrong admin pass given by client
5. define IR_ERR_SPEC 5 // Wrong spec pass given by client
6. define IR_ERR_NOSPEC 6 // Spectator pass required, but none given

==================================

Regular insim packets that a relay client can send to host :

For anyone TINY_VER TINY_PING TINY_SCP TINY_SST TINY_GTH TINY_ISM TINY_NCN TINY_NPL TINY_RES TINY_REO TINY_RST TINY_AXI

Admin only TINY_VTC ISP_MST ISP_MSX ISP_MSL ISP_MTC ISP_SCH ISP_BFN ISP_BTN

The relay will also accept, but not forward

TINY_NONE // for relay-connection maintenance